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Sample records for clinical 3-tesla imager

  1. Solenoid coil for mouse-model MRI with a clinical 3-Tesla imager: body imaging

    OpenAIRE

    Hidalgo, S. S.; D. Jirak; S.E. Solis; Rodríguez, A.O.

    2009-01-01

    A solenoid coil was built for magnetic resonance imaging of the mice. A coil prototype composed of 5 turns, with a length of 4 cm and 2.5 cm radius was developed to acquire (whole) body mouse magnetic resonance images at 130 MHz and an insertable gradient coil set. Coil performance was measured using the Q factor for both the loaded and unloaded cases were 161.67 and 178.03, respectively. These Q factors compare very well with those values reported in the literature. The images were acquired ...

  2. Imaging Findings of Brain Death on 3-Tesla MRI

    International Nuclear Information System (INIS)

    To demonstrate the usefulness of 3-tesla (3T) magnetic resonance imaging (MRI) including T2-weighted imaging (T2WI), diffusion weighted imaging (DWI), time-of-flight (TOF) magnetic resonance angiography (MRA), T2*-weighted gradient recalled echo (GRE), and susceptibility weighted imaging (SWI) in diagnosing brain death. Magnetic resonance imaging findings for 10 patients with clinically verified brain death (group I) and seven patients with comatose or stuporous mentality who did not meet the clinical criteria of brain death (group II) were retrospectively reviewed. Tonsilar herniation and loss of intraarterial flow signal voids (LIFSV) on T2WI were highly sensitive and specific findings for the diagnosis of brain death (p < 0.001 and < 0.001, respectively). DWI, TOF-MRA, and GRE findings were statistically different between the two groups (p = 0.015, 0.029, and 0.003, respectively). However, cortical high signal intensities in T2WI and SWI findings were not statistically different between the two group (p = 0.412 and 1.0, respectively). T2-weighted imaging, DWI, and MRA using 3T MRI may be useful for diagnosing brain death. However, SWI findings are not specific due to high false positive findings.

  3. Imaging Findings of Brain Death on 3-Tesla MRI

    Energy Technology Data Exchange (ETDEWEB)

    Sohn, Chul Ho [Dept. of Radiology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of); Lee, Hwa Pyung [Dept. of Occupational and Environmental Medicine, CHA Gumi Medical Center, CHA University, Gumi (Korea, Republic of); Park, Jun Beom [Dept. of Radiology, Korean Armed Force Daejeon Hospital, Daejeon (Korea, Republic of); Chang, Hyuk Won; Kim, Easlmaan; Park, Ui Jun; Kim, Hyoung Tae [Keimyung University College of Medicine, Dongsan Medical Center, Daegu (Korea, Republic of); Kim, Eun Hee [Dept. of Radiology, Seoul National University Bundang Hospital, Seongnam (Korea, Republic of); Ku, Jeong Hun [Dept. of Biomedical Engineering, Keimyung University College of Medicine, Daegu (Korea, Republic of)

    2012-09-15

    To demonstrate the usefulness of 3-tesla (3T) magnetic resonance imaging (MRI) including T2-weighted imaging (T2WI), diffusion weighted imaging (DWI), time-of-flight (TOF) magnetic resonance angiography (MRA), T2*-weighted gradient recalled echo (GRE), and susceptibility weighted imaging (SWI) in diagnosing brain death. Magnetic resonance imaging findings for 10 patients with clinically verified brain death (group I) and seven patients with comatose or stuporous mentality who did not meet the clinical criteria of brain death (group II) were retrospectively reviewed. Tonsilar herniation and loss of intraarterial flow signal voids (LIFSV) on T2WI were highly sensitive and specific findings for the diagnosis of brain death (p < 0.001 and < 0.001, respectively). DWI, TOF-MRA, and GRE findings were statistically different between the two groups (p = 0.015, 0.029, and 0.003, respectively). However, cortical high signal intensities in T2WI and SWI findings were not statistically different between the two group (p = 0.412 and 1.0, respectively). T2-weighted imaging, DWI, and MRA using 3T MRI may be useful for diagnosing brain death. However, SWI findings are not specific due to high false positive findings.

  4. Functional and perfusion magnetic resonance imaging at 3 tesla

    International Nuclear Information System (INIS)

    This thesis deals with the development and optimization of fast magnetic resonance imaging (MRI) methods for non-invasive functional studies of the human brain and perfusion imaging on a 3 Tesla (T) whole body NMR system. The functional MRI (fMRI) experiments performed showed that single-shot multi-echo EPI and spiral imaging techniques provide fast tools to obtain information about T2* distributions during functional activation in the human brain. Both sequences were found to be useful in the separation of different sources contributing to the functional MR signal like inflow or susceptibility effects in the various vascular environments. An fMRI study dealing with the involvement of prefrontal brain regions in movement preparation lead to inconsistent results. It could not be clarified if these were caused by problems during a spatial normalization process of the individual brains or if the functional paradigm, using very short inter-stimulus intervals, was not suited for the problem investigated. Blood flow velocity measurements in the human finger showed that the use of a strong, small-bore gradient system permits short echo times that reduce flow artefacts and allows high spatial resolution in order to keep systematic errors due to partial volume effects small. With regard to the perfusion investigations an inversion recovery snapshot-FLASH sequence was implemented, which allowed the acquisition of T1 parameter maps of the human brain within a few seconds. The accuracy of this method was demonstrated in test objects. The perfusion investigations with FAIR showed good qualitative results, whereas the quantitative analysis did not yield reproducible findings. A reason for the poor results could be the low signal-to-noise ratio (SNR) of the FAIR images or an incomplete global inversion of the magnetization due to the transmission characteristics of the radio-frequency coil. The BASE sequence that did not require a global inversion yielded quantitative perfusion

  5. Functional and perfusion magnetic resonance imaging at 3 tesla

    CERN Document Server

    Klarhoefer, M

    2001-01-01

    This thesis deals with the development and optimization of fast magnetic resonance imaging (MRI) methods for non-invasive functional studies of the human brain and perfusion imaging on a 3 Tesla (T) whole body NMR system. The functional MRI (fMRI) experiments performed showed that single-shot multi-echo EPI and spiral imaging techniques provide fast tools to obtain information about T2* distributions during functional activation in the human brain. Both sequences were found to be useful in the separation of different sources contributing to the functional MR signal like inflow or susceptibility effects in the various vascular environments. An fMRI study dealing with the involvement of prefrontal brain regions in movement preparation lead to inconsistent results. It could not be clarified if these were caused by problems during a spatial normalization process of the individual brains or if the functional paradigm, using very short inter-stimulus intervals, was not suited for the problem investigated. Blood flo...

  6. 3-Tesla functional magnetic resonance imaging-guided tumor resection

    Energy Technology Data Exchange (ETDEWEB)

    Hall, W.A. [Univ. of Minnesota Medical School, Minneapolis, MN (United States). Depts. of Neurosurgery; Univ. of Minnesota Medical School, Minneapolis, MN (United States). Dept. of Radiation Oncology; Univ. of Minnesota Medical School, Minneapolis, MN (United States). Dept. of Radiology; University of Minnesota Medical Center (MMC), Minneapolis, MN (United States); Truwit, C.L. [Univ. of Minnesota Medical School, Minneapolis, MN (United States). Dept. of Radiology; Univ. of Minnesota Medical School, Minneapolis, MN (United States). Dept. of Pediatrics; Univ. of Minnesota Medical School, Minneapolis, MN (United States). Dept. of Neurology; Hennepin Country Medical Center, Minneapolis, MN (United States). Dept. of Radiology

    2006-12-15

    Objective: We sought to determine the safety and efficacy of using 3-tesla (T) functional magnetic resonance imaging (fMRI) to guide brain tumor resection. Material and methods: From February 2004 to March 2006, fMRI was performed on 13 patients before surgical resection. Functional imaging was used to identify eloquent cortices for motor (8), speech (3), and motor and speech (2) activation using two different 3-T magnetic resonance (MR) scanners. Surgical resection was accomplished using a 1.5-T intraoperative MR system. Appropriate MR scan sequences were performed intraoperatively to determine and maximize the extent of the surgical resection. Results: Tumors included six oligodendrogliomas, three meningiomas, two astrocytomas and two glioblastomas multiforme. The fMRI data was accurate in all cases. After surgery, two patients had hemiparesis, two had worsening of their speech, and one had worsening of speech and motor function. Neurological function returned to normal in all patients within 1 month. Complete resections were possible in 10 patients (77%). Two patients had incomplete resections because of the proximity of their tumors to functional areas. Biopsy was performed in another patient with an astrocytoma in the motor strip. Conclusion: 3-T fMRI was accurate for locating neurologic function before tumor resection near eloquent cortex. (orig.)

  7. Evaluation of slice accelerations using multiband echo planar imaging at 3 Tesla

    OpenAIRE

    Xu, Junqian; Moeller, Steen; Auerbach, Edward J.; Strupp, John; Stephen M Smith; Feinberg, David A.; Yacoub, Essa; Uğurbil, Kâmil

    2013-01-01

    We evaluate residual aliasing among simultaneously excited and acquired slices in slice accelerated multiband (MB) echo planar imaging (EPI). No in-plane accelerations were used in order to maximize and evaluate achievable slice acceleration factors at 3 Tesla. We propose a novel leakage (L-) factor to quantify the effects of signal leakage between simultaneously acquired slices. With a standard 32-channel receiver coil at 3 Tesla, we demonstrate that slice acceleration factors of up to eight...

  8. Magnetic resonance imaging of epilepsy at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Craven, I., E-mail: ian.craven@sth.nhs.u [Department of Radiology, Royal Hallamshire Hospital, Sheffield (United Kingdom); Griffiths, P.D.; Hoggard, N. [Academic Unit of Radiology, Royal Hallamshire Hospital, Sheffield (United Kingdom)

    2011-03-15

    Patients with epilepsy often have a structural cause for their seizures and may benefit from surgical resection. As recommended in the National Institute of Health and Clinical Excellence (NICE) guidelines, magnetic resonance imaging (MRI) is used to screen for structural abnormalities in these patients and there is increasing evidence that 3T MRI has better sensitivity and specificity than 1.5T. This article reviews the imaging findings of many of the common diseases that can cause epilepsy.

  9. Magnetic resonance imaging of epilepsy at 3 Tesla

    International Nuclear Information System (INIS)

    Patients with epilepsy often have a structural cause for their seizures and may benefit from surgical resection. As recommended in the National Institute of Health and Clinical Excellence (NICE) guidelines, magnetic resonance imaging (MRI) is used to screen for structural abnormalities in these patients and there is increasing evidence that 3T MRI has better sensitivity and specificity than 1.5T. This article reviews the imaging findings of many of the common diseases that can cause epilepsy.

  10. A systematic review of the utility of 1.5 versus 3 Tesla magnetic resonance brain imaging in clinical practice and research

    Energy Technology Data Exchange (ETDEWEB)

    Wardlaw, Joanna M. [Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Edinburgh (United Kingdom); University of Edinburgh, Division of Clinical Neurosciences, Edinburgh (United Kingdom); Western General Hospital, SINAPSE Collaboration, Brain Research Imaging Centre, Division of Clinical Neurosciences, Edinburgh (United Kingdom); Brindle, Will; Casado, Ana M.; Thomas, Brenda; Morris, Zoe [University of Edinburgh, Division of Clinical Neurosciences, Edinburgh (United Kingdom); Shuler, Kirsten; Henderson, Moira; Munoz Maniega, Susana; Lymer, Katherine; Pernet, Cyril; Tao, Yuehui [Terry; Parikh, Jehill; Royle, Natalie A.; Bastin, Mark E.; Farrall, Andrew; Valdes Hernandez, Maria C. [Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Edinburgh (United Kingdom); University of Edinburgh, Division of Clinical Neurosciences, Edinburgh (United Kingdom); Macfarlane, Jennifer [Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Edinburgh (United Kingdom); University of Dundee, Dundee (United Kingdom); Nailon, William [University of Edinburgh, Edinburgh Cancer Centre, Edinburgh (United Kingdom); Ahearn, Trevor [Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Edinburgh (United Kingdom); University of Aberdeen, Institute of Medical Sciences, Aberdeen (United Kingdom); Mumuni, Abdul Nashirudeen [Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Edinburgh (United Kingdom); University of Glasgow, Department of Clinical Physics, Glasgow (United Kingdom); Mugruza, Carlos [Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Edinburgh (United Kingdom); University of Dundee, School of Psychology, Dundee (United Kingdom); McLean, John [Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Edinburgh (United Kingdom); University of Glasgow, Institute of Neurological Sciences, Glasgow (United Kingdom); Chakirova, Goultchira [Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Edinburgh (United Kingdom); University of Edinburgh, Division of Psychiatry, Edinburgh (United Kingdom); Simpson, Johanna [Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Edinburgh (United Kingdom); University of Stirling, Department of Psychology, Stirling (United Kingdom); Stanfield, Andrew C. [University of Edinburgh, Division of Psychiatry, Edinburgh (United Kingdom); Johnston, Harriet [Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Edinburgh (United Kingdom); University of St Andrews, Department of Psychology, St Andrews (United Kingdom); De Wilde, Janet [Scottish Imaging Network, A Platform for Scientific Excellence (SINAPSE) Collaboration, Edinburgh (United Kingdom); University of Edinburgh, Division of Clinical Neurosciences, Edinburgh (United Kingdom); The Higher Education Academy, York (United Kingdom); Weir, Nick [Royal Infirmary of Edinburgh, Department of Medical Physics, Edinburgh (United Kingdom); Collaboration: SINAPSE Collaborative Group

    2012-11-15

    MRI at 3 T is said to be more accurate than 1.5 T MR, but costs and other practical differences mean that it is unclear which to use. We systematically reviewed studies comparing diagnostic accuracy at 3 T with 1.5 T. We searched MEDLINE, EMBASE and other sources from 1 January 2000 to 22 October 2010 for studies comparing diagnostic accuracy at 1.5 and 3 T in human neuroimaging. We extracted data on methodology, quality criteria, technical factors, subjects, signal-to-noise, diagnostic accuracy and errors according to QUADAS and STARD criteria. Amongst 150 studies (4,500 subjects), most were tiny, compared old 1.5 T with new 3 T technology, and only 22 (15 %) described diagnostic accuracy. The 3 T images were often described as ''crisper'', but we found little evidence of improved diagnosis. Improvements were limited to research applications [functional MRI (fMRI), spectroscopy, automated lesion detection]. Theoretical doubling of the signal-to-noise ratio was not confirmed, mostly being 25 %. Artefacts were worse and acquisitions took slightly longer at 3 T. Objective evidence to guide MRI purchasing decisions and routine diagnostic use is lacking. Rigorous evaluation accuracy and practicalities of diagnostic imaging technologies should be the routine, as for pharmacological interventions, to improve effectiveness of healthcare. (orig.)

  11. A systematic review of the utility of 1.5 versus 3 Tesla magnetic resonance brain imaging in clinical practice and research

    International Nuclear Information System (INIS)

    MRI at 3 T is said to be more accurate than 1.5 T MR, but costs and other practical differences mean that it is unclear which to use. We systematically reviewed studies comparing diagnostic accuracy at 3 T with 1.5 T. We searched MEDLINE, EMBASE and other sources from 1 January 2000 to 22 October 2010 for studies comparing diagnostic accuracy at 1.5 and 3 T in human neuroimaging. We extracted data on methodology, quality criteria, technical factors, subjects, signal-to-noise, diagnostic accuracy and errors according to QUADAS and STARD criteria. Amongst 150 studies (4,500 subjects), most were tiny, compared old 1.5 T with new 3 T technology, and only 22 (15 %) described diagnostic accuracy. The 3 T images were often described as ''crisper'', but we found little evidence of improved diagnosis. Improvements were limited to research applications [functional MRI (fMRI), spectroscopy, automated lesion detection]. Theoretical doubling of the signal-to-noise ratio was not confirmed, mostly being 25 %. Artefacts were worse and acquisitions took slightly longer at 3 T. Objective evidence to guide MRI purchasing decisions and routine diagnostic use is lacking. Rigorous evaluation accuracy and practicalities of diagnostic imaging technologies should be the routine, as for pharmacological interventions, to improve effectiveness of healthcare. (orig.)

  12. Preoperative 3-Tesla Multiparametric Endorectal Magnetic Resonance Imaging Findings and the Odds of Upgrading and Upstaging at Radical Prostatectomy in Men With Clinically Localized Prostate Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Hegde, John V. [Harvard Medical School, Boston, Massachusetts (United States); Department of Radiology, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Chen, Ming-Hui [Department of Statistics, University of Connecticut, Storrs, Connecticut (United States); Mulkern, Robert V. [Department of Radiology, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Department of Radiology, Children' s Hospital Boston, Boston, Massachusetts (United States); Fennessy, Fiona M. [Department of Radiology, Brigham and Women' s Hospital, Boston, Massachusetts (United States); Department of Imaging, Dana-Farber Cancer Institute, Boston, Massachusetts (United States); D' Amico, Anthony V. [Department of Radiation Oncology, Brigham and Women' s Hospital and Dana-Farber Cancer Institute, Boston, Massachusetts (United States); Tempany, Clare M.C., E-mail: ctempany@bwh.harvard.edu [Division of MRI, Department of Radiology, Brigham and Women' s Hospital, Boston, Massachusetts (United States)

    2013-02-01

    Purpose: To investigate whether 3-T esla (3T) multiparametric endorectal MRI (erMRI) can add information to established predictors regarding occult extraprostatic or high-grade prostate cancer (PC) in men with clinically localized PC. Methods and Materials: At a single academic medical center, this retrospective study's cohort included 118 men with clinically localized PC who underwent 3T multiparametric erMRI followed by radical prostatectomy, from 2008 to 2011. Multivariable logistic regression analyses in all men and in 100 with favorable-risk PC addressed whether erMRI evidence of T3 disease was associated with prostatectomy T3 or Gleason score (GS) 8-10 (in patients with biopsy GS {<=}7) PC, adjusting for age, prostate-specific antigen level, clinical T category, biopsy GS, and percent positive biopsies. Results: The accuracy of erMRI prediction of extracapsular extension and seminal vesicle invasion was 75% and 95%, respectively. For all men, erMRI evidence of a T3 lesion versus T2 was associated with an increased odds of having pT3 disease (adjusted odds ratio [AOR] 4.81, 95% confidence interval [CI] 1.36-16.98, P=.015) and pGS 8-10 (AOR 5.56, 95% CI 1.10-28.18, P=.038). In the favorable-risk population, these results were AOR 4.14 (95% CI 1.03-16.56), P=.045 and AOR 7.71 (95% CI 1.36-43.62), P=.021, respectively. Conclusions: Three-Tesla multiparametric erMRI in men with favorable-risk PC provides information beyond that contained in known preoperative predictors about the presence of occult extraprostatic and/or high-grade PC. If validated in additional studies, this information can be used to counsel men planning to undergo radical prostatectomy or radiation therapy about the possible need for adjuvant radiation therapy or the utility of adding hormone therapy, respectively.

  13. Travelling Wave Magnetic Resonance Imaging at 3 Tesla

    OpenAIRE

    Vazquez, F; Martin, R.; Marrufo, O.; Rodriguez, A. O.

    2013-01-01

    Waveguides have been successfully used to generate magnetic resonance images at 7 T with whole-body systems. The bore limits the magnetic resonance signal transmitted because its specific cut-off frequency is greater than the majority of resonant frequencies. This restriction can be overcome by using a parallel-plate waveguide whose cut-off frequency is zero for the transversal electric modes and it can propagate any frequency. To investigate the potential benefits for whole-body imaging at 3...

  14. Travelling Wave Magnetic Resonance Imaging at 3 Tesla

    CERN Document Server

    Vazquez, F; Marrufo, O; Rodriguez, A O

    2013-01-01

    Waveguides have been successfully used to generate magnetic resonance images at 7 T with whole-body systems. The bore limits the magnetic resonance signal transmitted because its specific cut-off frequency is greater than the majority of resonant frequencies. This restriction can be overcome by using a parallel-plate waveguide whose cut-off frequency is zero for the transversal electric modes and it can propagate any frequency. To investigate the potential benefits for whole-body imaging at 3 T, we compare numerical simulations at 1.5 T, 3 T, 7 T, and 9 T via the propagation of the parallel-plate waveguide principal mode filled with a cylindrical phantom and two surface coils. B1 mapping was computed to investigate the feasibility of this approach at 3T. The point spread function method was used to measure the imager performance for the traveling-wave magnetic resonance imaging experiment. Human leg images were acquired to experimentally validate this approach. The principal mode shows very little field magni...

  15. Single-row vs. double-row arthroscopic rotator cuff repair: clinical and 3 Tesla MR arthrography results

    Directory of Open Access Journals (Sweden)

    Tudisco Cosimo

    2013-01-01

    Full Text Available Abstract Background Arthroscopic rotator cuff repair has become popular in the last few years because it avoids large skin incisions and deltoid detachment and dysfunction. Earlier arthroscopic single-row (SR repair methods achieved only partial restoration of the original footprint of the tendons of the rotator cuff, while double-row (DR repair methods presented many biomechanical advantages and higher rates of tendon-to-bone healing. However, DR repair failed to demonstrate better clinical results than SR repair in clinical trials. MR imaging at 3 Tesla, especially with intra-articular contrast medium (MRA, showed a better diagnostic performance than 1.5 Tesla in the musculoskeletal setting. The objective of this study was to retrospectively evaluate the clinical and 3 Tesla MRA results in two groups of patients operated on for a medium-sized full-thickness rotator cuff tear with two different techniques. Methods The first group consisted of 20 patients operated on with the SR technique; the second group consisted of 20 patients operated on with the DR technique. All patients were evaluated at a minimum of 3 years after surgery. The primary end point was the re-tear rate at 3 Tesla MRA. The secondary end points were the Constant-Murley Scale (CMS, the Simple Shoulder Test (SST scores, surgical time and implant expense. Results The mean follow-up was 40 months in the SR group and 38.9 months in the DR group. The mean postoperative CMS was 70 in the SR group and 68 in the DR group. The mean SST score was 9.4 in the SR group and 10.1 in the DR group. The re-tear rate was 60% in the SR group and 25% in the DR group. Leakage of the contrast medium was observed in all patients. Conclusions To the best of our knowledge, this is the first report on 3 Tesla MRA in the evaluation of two different techniques of rotator cuff repair. DR repair resulted in a statistically significant lower re-tear rate, with longer surgical time and higher implant

  16. Chemical exchange saturation transfer MR imaging of Parkinson's disease at 3 Tesla

    International Nuclear Information System (INIS)

    To demonstrate the feasibility of using chemical exchange saturation transfer (CEST) imaging to detect Parkinson's disease (PD) in patients at 3 Tesla. Twenty-seven PD patients (17 men and 10 women; age range, 54-77 years) and 22 age-matched normal controls (13 men and 9 women; age range, 55-73 years) were examined on a 3-Tesla MRI system. Magnetization transfer spectra with 31 different frequency offsets (-6 to 6 ppm) were acquired at two transverse slices of the head, including the basal ganglia and midbrain. One-way analysis of variance tests was used to compare the differences in CEST imaging signals between PD patients and normal controls. Total CEST signal between the offsets of 0 and 4 ppm in the substantia nigra was significantly lower in PD patients than in normal controls (P = 0.006), which could be associated with the loss of dopaminergic neurons. Protein-based CEST imaging signals at the offset of 3.5 ppm in the globus pallidus, putamen and caudate were significantly increased in PD patients, compared to normal controls (P < 0.001, P = 0.003, P < 0.001, respectively). CEST imaging signals could potentially serve as imaging biomarkers to aid in the non-invasive molecular diagnosis of PD. (orig.)

  17. Chemical exchange saturation transfer MR imaging of Parkinson's disease at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Li, Chunmei; Peng, Shuai; Wang, Rui; Chen, Min [Beijing Hospital, Department of Radiology, Beijing (China); Chen, Haibo; Su, Wen [Beijing Hospital, Department of Neurology, Beijing (China); Zhao, Xuna [Peking University, Center for MRI Research and Beijing City Key Lab for Medical Physics and Engineering, Beijing (China); Zhou, Jinyuan [Johns Hopkins University, Department of Radiology, Baltimore, MD (United States)

    2014-10-15

    To demonstrate the feasibility of using chemical exchange saturation transfer (CEST) imaging to detect Parkinson's disease (PD) in patients at 3 Tesla. Twenty-seven PD patients (17 men and 10 women; age range, 54-77 years) and 22 age-matched normal controls (13 men and 9 women; age range, 55-73 years) were examined on a 3-Tesla MRI system. Magnetization transfer spectra with 31 different frequency offsets (-6 to 6 ppm) were acquired at two transverse slices of the head, including the basal ganglia and midbrain. One-way analysis of variance tests was used to compare the differences in CEST imaging signals between PD patients and normal controls. Total CEST signal between the offsets of 0 and 4 ppm in the substantia nigra was significantly lower in PD patients than in normal controls (P = 0.006), which could be associated with the loss of dopaminergic neurons. Protein-based CEST imaging signals at the offset of 3.5 ppm in the globus pallidus, putamen and caudate were significantly increased in PD patients, compared to normal controls (P < 0.001, P = 0.003, P < 0.001, respectively). CEST imaging signals could potentially serve as imaging biomarkers to aid in the non-invasive molecular diagnosis of PD. (orig.)

  18. Cortical microinfarcts detected in vivo on 3 tesla MRI : Clinical and radiological correlates

    NARCIS (Netherlands)

    Van Dalen, Jan Willem; Scuric, Eva E M; Van Veluw, Susanne J.; Caan, Matthan W A; Nederveen, Aart J.; Biessels, Geert Jan; Van Gool, Willem A.; Richard, Edo

    2015-01-01

    Background and Purpose-Cortical microinfarcts (CMIs) are a common postmortem finding associated with vascular risk factors, cognitive decline, and dementia. Recently, CMIs identified in vivo on 7 Tesla MRI also proved retraceable on 3 Tesla MRI. Methods-We evaluated CMIs on 3 Tesla MRI in a populati

  19. Cortical microinfarcts detected in vivo on 3 Tesla MRI: clinical and radiological correlates

    NARCIS (Netherlands)

    Dalen, J.W. van; Scuric, E.E.; Veluw, S.J. van; Caan, M.W.; Nederveen, A.J.; Biessels, G.J.; Gool, W.A. van; Richard, E.

    2015-01-01

    BACKGROUND AND PURPOSE: Cortical microinfarcts (CMIs) are a common postmortem finding associated with vascular risk factors, cognitive decline, and dementia. Recently, CMIs identified in vivo on 7 Tesla MRI also proved retraceable on 3 Tesla MRI. METHODS: We evaluated CMIs on 3 Tesla MRI in a popula

  20. High resolution T{sub 2}{sup *}-weighted magnetic resonance imaging at 3 Tesla using PROPELLER-EPI

    Energy Technology Data Exchange (ETDEWEB)

    Kraemer, Martin; Reichenbach, Juergen R. [Jena University Hospital (Germany). Medical Physics Group

    2014-09-01

    We report the application of PROPELLER-EPI for high resolution T{sub 2}{sup *}-weighted imaging with sub-millimeter in-plane resolution on a clinical 3 Tesla scanner. Periodically rotated blades of a long-axis PROPELLER-EPI sequence were acquired with fast gradient echo readout and acquisition matrix of 320 x 50 per blade. Images were reconstructed by using 2D-gridding, phase and geometric distortion correction and compensation of resonance frequency drifts that occurred during extended measurements. To characterize these resonance frequency offsets, short FID calibration measurements were added to the PROPELLER-EPI sequence. Functional PROPELLER-EPI was performed with volunteers using a simple block design of right handed finger tapping. Results indicate that PROPELLER-EPI can be employed for fast, high resolution T{sub 2}{sup *}-weighted imaging provided geometric distortions and possible resonance frequency drifts are properly corrected. Even small resonance frequency drifts below 10 Hz as well as non-corrected geometric distortions degraded image quality substantially. In the initial fMRI experiment image quality and signal-to-noise ratio was sufficient for obtaining high resolution functional activation maps. (orig.)

  1. Improving quality of arterial spin labeling MR imaging at 3 Tesla with a 32-channel coil and parallel imaging.

    OpenAIRE

    Ferré, Jean-Christophe; Petr, Jan; Bannier, Elise; Barillot, Christian; Gauvrit, Jean-Yves

    2012-01-01

    PURPOSE: To compare 12-channel and 32-channel phased-array coils and to determine the optimal parallel imaging (PI) technique and factor for brain perfusion imaging using Pulsed Arterial Spin labeling (PASL) at 3 Tesla (T). MATERIALS AND METHODS: Twenty-seven healthy volunteers underwent 10 different PASL perfusion PICORE Q2TIPS scans at 3T using 12-channel and 32-channel coils without PI and with GRAPPA or mSENSE using factor 2. PI with factor 3 and 4 were used only with the 32-channel coil....

  2. A review of the safety implications of magnetic resonance imaging at field strengths of 3 Tesla and above

    Energy Technology Data Exchange (ETDEWEB)

    Crook, Neil [Alliance Medical, Iceni Centre, Warwick Technology Park, Warwick CV34 6DA (United Kingdom)], E-mail: ncrook@alliance.co.uk; Robinson, Leslie [Dept. of Diagnostic Radiography, School of Healthcare Professions, Faculty of Health and Social Care, University of Salford, Salford, Greater Manchester M6 6PU (United Kingdom)

    2009-11-15

    Rationale: Diagnostic imaging is being driven by technological developments particularly so in the field of Magnetic Resonance Imaging (MRI). Electromagnetic fields used to produce images are becoming much stronger and switched more rapidly and it is essential that safety advice remains appropriate and current. Using a systematic methodology, this review aims to identify the clinical safety implications in performing MRI at field strengths of 3 Tesla (T) and above and determine whether the current clinical safety guidelines are appropriate. Method: References were sourced from The Cochrane Library, Centre for Reviews and Dissemination Science Direct, PubMed and Google Scholar. Related websites searched included The British Institute of Radiology, Society of Radiographers, Royal College of Radiologists, The Institution of Engineering and Technology, IMRSER (Institute for Magnetic Resonance Safety, Education, and Research), MagNet (NHS PASA). References supplied in retrieved papers were also checked for potential relevance. The use of consistent search terminology and inclusion and exclusion criteria ensured quality and provided rigour to conclusions drawn. Conclusion: According to the literature retrieved, the current body of knowledge has allowed safety guidelines to be established for patient safety and these are both appropriate and valid at field strengths of 3 T.

  3. Functionality of veterinary identification microchips following low- (0.5 tesla) and high-field (3 tesla) magnetic resonance imaging.

    Science.gov (United States)

    Piesnack, Susann; Frame, Mairi E; Oechtering, Gerhard; Ludewig, Eberhard

    2013-01-01

    The ability to read patient identification microchips relies on the use of radiofrequency pulses. Since radiofrequency pulses also form an integral part of the magnetic resonance imaging (MRI) process, the possibility of loss of microchip function during MRI scanning is of concern. Previous clinical trials have shown microchip function to be unaffected by MR imaging using a field strength of 1 Tesla and 1.5. As veterinary MRI scanners range widely in field strength, this study was devised to determine whether exposure to lower or higher field strengths than 1 Tesla would affect the function of different types of microchip. In a phantom study, a total of 300 International Standards Organisation (ISO)-approved microchips (100 each of three different types: ISO FDX-B 1.4 × 9 mm, ISO FDX-B 2.12 × 12 mm, ISO HDX 3.8 × 23 mm) were tested in a low field (0.5) and a high field scanner (3.0 Tesla). A total of 50 microchips of each type were tested in each scanner. The phantom was composed of a fluid-filled freezer pack onto which a plastic pillow and a cardboard strip with affixed microchips were positioned. Following an MRI scan protocol simulating a head study, all of the microchips were accurately readable. Neither 0.5 nor 3 Tesla imaging affected microchip function in this study.

  4. White Matter Brain Lesions in Midlife Familial Hypercholesterolemic Patients at 3-Tesla Magnetic Resonance Imaging

    International Nuclear Information System (INIS)

    Background: Patients with hypercholesterolemia of 60 years and older have an increased risk for white matter brain lesions and dementia. Purpose: To investigate whether patients with familial hypercholesterolemia (FH) develop white matter lesions at 3-Tesla (T) MRI as early as in midlife. Material and Methods: Non-diabetic, non-smoking, and non-hypertensive heterozygous FH patients on treatment with maximally tolerated dose of a statin for more than 5 years (n = 14) and matched controls (n = 22) aged 25 to 60 years of age were studied. Imaging was performed at 3T with a fluid-attenuated T2-weighted MR pulse sequence and a T1-weighted spin-echo pulse sequence following 10 ml of i.v. gadopentetate dimeglumine. Images were evaluated by two independent readers. Fasting blood samples were taken. Student's t test was employed at P<0.05. Results: Three volunteers and one FH patient had white matter lesions (P<0.53). No other evidence of past ischemic stroke was observed. Mean total serum cholesterol and low-density lipoprotein (LDL) cholesterol were significantly higher in the FH group (6.0±1.1 vs. 5.1±0.9 mmol/l, P<0.02 and 4.1±0.9 vs. 3.1±0.8 mmol/l, P<0.004, respectively). Conclusion: Heterozygous FH patients on statin treatment in the age range of 25 to 60 years are not at increased risk of white matter lesions at 3T MRI

  5. White Matter Brain Lesions in Midlife Familial Hypercholesterolemic Patients at 3-Tesla Magnetic Resonance Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, S.A.; O' Regan, D.P.; Fitzpatrick, J.; Neuwirth, C.; Potter, E.; Tosi, I.; Hajnal, J.V.; Naoumova, R.P. (Imaging Sciences Dept. and Clinical Research Facility, MRC Clinical Sciences Centre, London (GB))

    2008-03-15

    Background: Patients with hypercholesterolemia of 60 years and older have an increased risk for white matter brain lesions and dementia. Purpose: To investigate whether patients with familial hypercholesterolemia (FH) develop white matter lesions at 3-Tesla (T) MRI as early as in midlife. Material and Methods: Non-diabetic, non-smoking, and non-hypertensive heterozygous FH patients on treatment with maximally tolerated dose of a statin for more than 5 years (n = 14) and matched controls (n = 22) aged 25 to 60 years of age were studied. Imaging was performed at 3T with a fluid-attenuated T2-weighted MR pulse sequence and a T1-weighted spin-echo pulse sequence following 10 ml of i.v. gadopentetate dimeglumine. Images were evaluated by two independent readers. Fasting blood samples were taken. Student's t test was employed at P<0.05. Results: Three volunteers and one FH patient had white matter lesions (P<0.53). No other evidence of past ischemic stroke was observed. Mean total serum cholesterol and low-density lipoprotein (LDL) cholesterol were significantly higher in the FH group (6.0+-1.1 vs. 5.1+-0.9 mmol/l, P<0.02 and 4.1+-0.9 vs. 3.1+-0.8 mmol/l, P<0.004, respectively). Conclusion: Heterozygous FH patients on statin treatment in the age range of 25 to 60 years are not at increased risk of white matter lesions at 3T MRI

  6. Experimental autoimmune encephalomyelitis (EAE): lesion visualization on a 3 tesla Clinical whole-body system after intraperitoneal contrast injection

    Energy Technology Data Exchange (ETDEWEB)

    Heckl, S.; Naegele, T.; Klose, U. [Dept. of Neuroradiology, Medical School, Univ. of Tuebingen (Germany); Herrmann, M.; Gaertner, S.; Weissert, R. [Dept. of Neurology, Medical School, Univ. of Tuebingen (Germany); Schick, F. [Dept. of Radiology, Medical School, Univ. of Tuebingen (Germany); Kueker, W. [Dept. of Neuroradiology, Medical School, Univ. of Tuebingen (Germany); Dept. of Neuroradiology, Radcliffe Infirmary, Oxford, England (United Kingdom)

    2004-11-01

    Purpose: To investigate the intravital visibility of CNS lesions in rats with experimental autoimmune encephalomyelitis (EAE), the animal correlate of multiple sclerosis, using a 3-Tesla (T) wholebody MR system. Materials and Methods: Three healthy Dark Agouti (DA) rats and 16 DA rats with clinical signs of EAE were examined on a 3T whole body-system using a normal wrist coil. In total, 25 examinations were preformed using T2- and T1-weighted images in transverse and sagittal orientation with a slice thickness of 2 mm or 1 mm (voxel size up to 0.2 x 0.2 x 1 mm). Sedation was achieved by intraperitoneal injection of ketamine and xylazine. In addition, T1-weighted images were obtained after the instillation of 1.0 ml of gadolinium diethylenetriamine pentaacetic acid (Gd-DTPA) (0.5 mmol/ml) into the peritoneal cavity. Results: T2- and T1-weighted images of the brain and spinal cord with high spatial and contrast resolution could be obtained in all animals. The anatomical details of the olfactory bulb glomeruli, cerebellum foliae, ventricles and corpus callosum were clearly visible. The EAE lesions presented as hyperintense area in T2-weighted images and could be demonstrated in all clinically affected animals by MRI and histologically verified. In total, the 16 affected rats had 28 cerebral and 2 spinal cord lesions (range 1 to 4, median 2). Contrast enhancement was noted in 12 animals and ranked as severe in ten and moderate in two cases. No adverse effects were noted due to sedation or intraperitoneal contrast injection. Conclusions: The intravital demonstration of cerebral and spinal cord EAE lesions in rats is possible on a 3T whole-body MR scanner using a normal wrist coil. Intraperitoneal injection of ketamine/xylazine and contrast agent is an easy, safe and effective procedure in rats. (orig.)

  7. Evaluation of 100 brain examinations using a 3 Tesla MR-compatible incubator - safety, handling, and image quality

    Energy Technology Data Exchange (ETDEWEB)

    Sirin, Selma; Goericke, Sophia L.; Kinner, Sonja; Schweiger, Bernd [University Hospital Essen, Institute of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Huening, Britta M.; Stein, Anja; Felderhoff-Mueser, Ursula [University Hospital Essen, Department of Neonatology, Division of Pediatrics I, Essen (Germany)

    2013-10-15

    Several studies have revealed the importance of brain imaging in term and preterm infants. The aim of this retrospective study was to review safety, handling, and image quality of MR brain imaging using a new 3 Tesla MR-compatible incubator. Between 02/2011 and 05/2012 100 brain MRIs (84 infants, mean gestational age 32.2 {+-} 4.7 weeks, mean postmenstrual age at imaging 40.6 {+-} 3.4 weeks) were performed using a 3 Tesla MR-compatible incubator with dedicated, compatible head coil. Seventeen examinations (13 infants, mean gestational age 35.1 {+-} 5.4 weeks, mean postmenstrual age at imaging 47.8 {+-} 7.4 weeks) with a standard head coil served as a control. Image analysis was performed by a neuroradiologist and a pediatric radiologist in consensus. All but two patients with known apnea were transferred to the MR unit and scanned without problems. Handling was easier and faster with the incubator; relevant motion artifacts (5.9 vs. 10.8 %) and the need for repetitive sedation (43.0 vs. 86.7 %) were reduced. Considering only images not impaired by motion artifacts, image quality (4.8 {+-} 0.4 vs. 4.3 {+-} 0.8, p = 0.047) and spatial resolution (4.7 {+-} 0.4 vs. 4.2 {+-} 0.6, p = 0.011) of T2-weighted images were scored significantly higher in patients imaged with the incubator. SNR increased significantly (171.6 {+-} 54.5 vs. 80.5 {+-} 19.8, p < 0.001) with the use of the incubator. Infants can benefit from the use of a 3 Tesla MR-compatible incubator because of its safety, easier, and faster handling (compared to standard imaging) and possibility to obtain high-quality MR images even in unstable patients. (orig.)

  8. Evaluation of 100 brain examinations using a 3 Tesla MR-compatible incubator - safety, handling, and image quality

    International Nuclear Information System (INIS)

    Several studies have revealed the importance of brain imaging in term and preterm infants. The aim of this retrospective study was to review safety, handling, and image quality of MR brain imaging using a new 3 Tesla MR-compatible incubator. Between 02/2011 and 05/2012 100 brain MRIs (84 infants, mean gestational age 32.2 ± 4.7 weeks, mean postmenstrual age at imaging 40.6 ± 3.4 weeks) were performed using a 3 Tesla MR-compatible incubator with dedicated, compatible head coil. Seventeen examinations (13 infants, mean gestational age 35.1 ± 5.4 weeks, mean postmenstrual age at imaging 47.8 ± 7.4 weeks) with a standard head coil served as a control. Image analysis was performed by a neuroradiologist and a pediatric radiologist in consensus. All but two patients with known apnea were transferred to the MR unit and scanned without problems. Handling was easier and faster with the incubator; relevant motion artifacts (5.9 vs. 10.8 %) and the need for repetitive sedation (43.0 vs. 86.7 %) were reduced. Considering only images not impaired by motion artifacts, image quality (4.8 ± 0.4 vs. 4.3 ± 0.8, p = 0.047) and spatial resolution (4.7 ± 0.4 vs. 4.2 ± 0.6, p = 0.011) of T2-weighted images were scored significantly higher in patients imaged with the incubator. SNR increased significantly (171.6 ± 54.5 vs. 80.5 ± 19.8, p < 0.001) with the use of the incubator. Infants can benefit from the use of a 3 Tesla MR-compatible incubator because of its safety, easier, and faster handling (compared to standard imaging) and possibility to obtain high-quality MR images even in unstable patients. (orig.)

  9. High-Resolution Magnetic Resonance Imaging of Trabecular Bone in the Wrist at 3 Tesla: Initial Results

    Energy Technology Data Exchange (ETDEWEB)

    Ludescher, B.; Martirosian, P.; Lenk, S.; Machann, J.; Dammann, F.; Schick, F.; Claussen, C.; Schlemmer, H. [Univ. Clinic, Tuebingen (Germany). Dept. of Diagnostic Radiology and Section on Experimental Radiology

    2005-05-01

    Purpose: To evaluate the feasibility of high-resolution magnetic resonance imaging (MRI) of trabecular bone of the wrist at 3 Tesla (3T) in vivo and to assess the potential benefit of the increased resolution for clinical assessment of structural changes in spongy bone. Material and Methods: High-resolution MRI of the wrist was performed with a whole-body 3T MR scanner using a dedicated circularly polarized transmit/receive wrist-coil. Two 3D-FISP sequences with a spatial resolution of 300x300x300 {mu}m{sup 3} in a measuring time of TA{approx}7:51 min, and 200x200x200 {mu}m{sup 3} in TA{approx}9:33 min were applied. Seven young healthy volunteers and three elderly subjects with suspected osteoporosis were examined. The signal-to-noise ratio (SNR) in the optimized setup at 3T was compared to measurements at 1.5T. Results: The images at 3T allow microscopic analysis of the bone structure at an isotropic spatial resolution of 200 {mu}m in examination times of <10 min. Differences in the structure of the spongy bone between normal and markedly osteoporotic subjects are well depicted. The SNR at 3T was found up to 16 times higher than at 1.5T applying unchanged imaging parameters. Conclusion: The proposed high-resolution MRI technique offers high potential in the diagnosis and follow-up of diseases with impaired bone structure of hand and/or wrist in clinical applications.

  10. Accuracy of accelerated cine MR imaging at 3 Tesla in longitudinal follow-up of cardiac function

    Energy Technology Data Exchange (ETDEWEB)

    Sandner, Torleif A.; Huber, Armin M.; Theisen, Daniel; Reiser, Maximilian F.; Wintersperger, Bernd J. [Ludwig-Maximilians-University, Department of Clinical Radiology, University Hospitals - Campus Grosshadern, Munich (Germany); Houck, Philip [Texas A and M University Health Science Center, Department of Cardiology, Scott and White Clinic and Hospital, Temple, TX (United States); Runge, Val M.; Sincleair, Spencer [Texas A and M University Health Science Center, Department of Radiology, Scott and White Clinic and Hospital, Temple, TX (United States)

    2008-10-15

    The ability of fast, parallel-imaging-based cine magnetic resonance (MR) to monitor global cardiac function in longitudinal exams at 3 Tesla was evaluated. Seventeen patients with chronic cardiac disease underwent serial cine MR imaging exams (n=3) at 3 Tesla. Data were acquired in short-axis orientation using cine steady-state free precession (SSFP) with a spatial resolution of 2.5 x 1.9 mm{sup 2} at 45 ms temporal resolution. Multislice imaging (three slices/breath-hold) was performed using TSENSE acceleration (R=3) and standard single-slice cine (non-TSENSE) was performed at identical locations in consecutive breath-holds. End-diastolic volume (EDV), end-systolic volume (ESV), ejection fraction (EF) and myocardial mass (MM) of both cine approaches were compared for individual time-points as well as for longitudinal comparison. TSENSE-cine did not show significant differences for EDV (2.6 ml; P=.79), ESV (2.2 ml; P=0.81), EF (-0.3%; P=0.95) and MM (2.4 g; P=0.72) in comparison with non-TSENSE. Longitudinal ANOVA analysis did not reveal significant differences for any parameter, neither for non-TSENSE data (all P>0.7) nor for TSENSE data (all P>0.9). Multifactorial ANOVA showed non-significant differences (all P>0.7) at comparable data variances. Data acquisition was significantly shortened using TSENSE. Threefold accelerated multislice cine at 3 Tesla allows accurate assessment of volumetric LV data and accurate longitudinal monitoring of global LV function at a substantially shorter overall examination time. (orig.)

  11. Optimized magnetic resonance sequences and parameters with operative assisted images for radical prostatectomy at 3 tesla-magnetic resonance image

    International Nuclear Information System (INIS)

    The objective of our study was to optimize magnetic resonance image (MRI) sequences and parameters using operative assisted images (three-dimensional images) for radical prostatectomy at 3 tesla (T) MRI. Five healthy volunteers underwent MRI on the 3.0 T scanner. Various sequences and parameters [Cube (echo time/repetition time (TE/TR)=18, 50, 90 ms/2000 ms), fast imaging employing steady state acquisition (FIESTA) (TE/TR/FA=2.4 ms/5 ms/40deg, 90deg), fast spoiled gradient recalled acquisition in the steady state (fSPGR) (TE/TR/FA=2.3 ms/11.2 ms/20deg), slice thickness=1.2 mm, matrix=192 x 160] were respectively compared. Several structures of the pelvis (the central zones and transition zones of the prostate, the peripheral zones of the prostate, seminal vesicles, rectum wall, bladder, muscle and fat) were determined. The signal intensities of these structures were measured on reformatted axial images and compared against several structures of the pelvis. Correlation with various sequences and parameters was based on the signal-to-noise ratio (SNR), the contrast ratio (CR) and the presence of artifacts. Student's t-test was used for statistical analysis. With Cube (TE/TR=50 ms/2000 ms), the average value of visual evaluation with artifacts was high, and SNR and CR were higher than for other sequence and parameters. Optimized MRI sequences and parameters were Cube (TE/TR=50 ms/2000 ms) which provides improved SNR and CR and the presence of artifacts with operative assisted images for radical prostatectomy. These operative assisted images obtained from Cube (TE/TR=50 ms/2000 ms) are likely to be useful for surgery. (author)

  12. 3 tesla magnetic resonance imaging in children and adults with congenital heart disease; 3-Tesla-Magnetresonanztomographie zur Untersuchung von Kindern und Erwachsenen mit angeborenen Herzfehlern

    Energy Technology Data Exchange (ETDEWEB)

    Voges, I.; Hart, C.; Kramer, H.H.; Rickers, C. [Universitaetsklinikum Schleswig-Holstein, Klinik fuer angeborene Herzfehler und Kinderkardiologie, Kiel (Germany); Jerosch-Herold, M. [Harvard Medical School, Department of Radiology, Brigham and Women' s Hospital, Boston (United States); Helle, M. [Universitaetsklinikum Schleswig-Holstein, Institut fuer Neuroradiologie, Kiel (Germany)

    2010-09-15

    Cardiovascular magnetic resonance imaging (CMR) has become a routinely used imaging modality for congenital heart disease. A CMR examination allows the assessment of thoracic anatomy, global and regional cardiac function, blood flow in the great vessels and myocardial viability and perfusion. In the clinical routine cardiovascular MRI is mostly performed at field strengths of 1.5 Tesla (T). Recently, magnetic resonance systems operating at a field strengths of 3 T became clinically available and can also be used for cardiovascular MRI. The main advantage of CMR at 3 T is the gain in the signal-to-noise ratio resulting in improved image quality and/or allowing higher acquisition speed. Several further differences compared to MRI systems with lower field strengths have to be considered for practical applications. This article describes the impact of CMR at 3 T in patients with congenital heart disease by meanings of methodical considerations and case studies. (orig.) [German] Die kardiovaskulaere Magnetresonanztomographie (MRT) hat sich zu einer etablierten bildgebenden Methode zur Untersuchung von Patienten mit angeborenen Herzfehlern entwickelt. Sie erlaubt in einer einzigen Untersuchung die exakte Beurteilung von Anatomie, globaler und regionaler Funktion, Blutfluessen sowie der myokardialen Perfusion und Vitalitaet. In der klinischen Routine erfolgen die Untersuchungen zumeist bei einer Feldstaerke von 1,5 Tesla (T), mittlerweile gibt es jedoch Geraete und Bildgebungstechniken, die die kardiovaskulaere MRT auch bei 3 T ermoeglichen. Der wesentliche Vorteil der MRT bei 3 T ist das hoehere Signal-zu-Rausch-Verhaeltnis, das sowohl zu einer Verbesserung der Bildqualitaet als auch zu einer Verkuerzung der Untersuchungszeit genutzt werden kann. Darueber hinaus bestehen verschiedene andere Unterschiede gegenueber Systemen mit niedriger Feldstaerke, die im praktischen Einsatz beachtet werden muessen. Dieser Artikel beschreibt die Erfahrungen der 3-T-MRT fuer die

  13. Magnetic resonance imaging evaluation after implantation of a titanium cervical disc prosthesis: a comparison of 1.5 and 3 Tesla magnet strength

    OpenAIRE

    Sundseth, Jarle; Jacobsen, Eva A.; Kolstad, Frode; Nygaard, Oystein P.; Zwart, John A.; Hol, Per K.

    2013-01-01

    Purpose Cervical disc prostheses induce significant amount of artifact in magnetic resonance imaging which may complicate radiologic follow-up after surgery. The purpose of this study was to investigate as to what extent the artifact, induced by the frequently used Discover® cervical disc prosthesis, impedes interpretation of the MR images at operated and adjacent levels in 1.5 and 3 Tesla MR. Methods Ten subsequent patients were investigated in both 1.5 and 3 Tesla MR with standard image seq...

  14. Utility and limitations of 3-Tesla diffusion-weighted magnetic resonance imaging for differentiation of renal tumors

    Energy Technology Data Exchange (ETDEWEB)

    Sevcenco, S., E-mail: sabina.sevcenco@meduniwien.ac.at [Medical University of Vienna, Dept. of Urology, Waehringer Gürtel 18-20, 1090 Vienna (Austria); Heinz-Peer, G., E-mail: gertraud.heinz-peer@meduniwien.ac.at [Medical University of Vienna, Dept. of Biomedical Imaging and Image-guided Therapy, Waehringer Gürtel 18-20, 1090 Vienna (Austria); Ponhold, L., E-mail: lothar.ponhold@meduniwien.ac.at [Medical University of Vienna, Dept. of Biomedical Imaging and Image-guided Therapy, Waehringer Gürtel 18-20, 1090 Vienna (Austria); Javor, D., E-mail: domagoj.javor@meduniwien.ac.at [Medical University of Vienna, Dept. of Biomedical Imaging and Image-guided Therapy, Waehringer Gürtel 18-20, 1090 Vienna (Austria); Kuehhas, F.E., E-mail: frenklin.kuehhas@meduniwien.ac.at [Medical University of Vienna, Dept. of Urology, Waehringer Gürtel 18-20, 1090 Vienna (Austria); Klingler, H.C., E-mail: christoph.klingler@meduniwien.ac.at [Medical University of Vienna, Dept. of Urology, Waehringer Gürtel 18-20, 1090 Vienna (Austria); Remzi, M., E-mail: mesut.remzi@gmx.at [Medical University of Vienna, Dept. of Urology, Waehringer Gürtel 18-20, 1090 Vienna (Austria); Weibl, P., E-mail: peter.weibl@meduniwien.ac.at [Medical University of Vienna, Dept. of Urology, Waehringer Gürtel 18-20, 1090 Vienna (Austria); Shariat, S.F., E-mail: sfshariat@gmail.com [Medical University of Vienna, Dept. of Urology, Waehringer Gürtel 18-20, 1090 Vienna (Austria); Baltzer, P.A., E-mail: pascal.baltzer@meduniwien.ac.at [Medical University of Vienna, Dept. of Biomedical Imaging and Image-guided Therapy, Waehringer Gürtel 18-20, 1090 Vienna (Austria)

    2014-06-15

    Objective: To investigate utility and limitations of 3-Tesla diffusion-weighted (DW) magnetic resonance imaging (MRI) for differentiation of benign versus malignant renal lesions and renal cell carcinoma (RCC) subtypes. Materials and methods: Sixty patients with 71 renal lesions underwent 3 Tesla DW-MRI of the kidney before diagnostic tissue confirmation. The images were retrospectively evaluated blinded to histology. Single-shot echo-planar imaging was used as the DW imaging technique. Apparent diffusion coefficient (ADC) values were measured and compared with histopathological characteristics. Results: There were 54 malignant and 17 benign lesions, 46 lesions being small renal masses ≤4 cm. Papillary RCC lesions had lower ADC values (p = 0.029) than other RCC subtypes (clear cell or chromophobe). Diagnostic accuracy of DW-MRI for differentiation of papillary from non-papillary RCC was 70.3% resulting in a sensitivity and specificity of 64.3% (95% CI, 35.1–87.2) and 77.1 (95% CI, 59.9–89.6%). Accuracy increased to 83.7% in small renal masses (≤4 cm diameter) and sensitivity and specificity were 75.0% and 88.5%, respectively. The ADC values did not differ significantly between benign and malignant renal lesions (p = 0.45). Conclusions: DW-MRI seems to distinguish between papillary and other subtypes of RCCs especially in small renal masses but could not differentiate between benign and malignant renal lesions. Therefore, the use of DW-MRI for preoperative differentiation of renal lesions is limited.

  15. Utility and limitations of 3-Tesla diffusion-weighted magnetic resonance imaging for differentiation of renal tumors

    International Nuclear Information System (INIS)

    Objective: To investigate utility and limitations of 3-Tesla diffusion-weighted (DW) magnetic resonance imaging (MRI) for differentiation of benign versus malignant renal lesions and renal cell carcinoma (RCC) subtypes. Materials and methods: Sixty patients with 71 renal lesions underwent 3 Tesla DW-MRI of the kidney before diagnostic tissue confirmation. The images were retrospectively evaluated blinded to histology. Single-shot echo-planar imaging was used as the DW imaging technique. Apparent diffusion coefficient (ADC) values were measured and compared with histopathological characteristics. Results: There were 54 malignant and 17 benign lesions, 46 lesions being small renal masses ≤4 cm. Papillary RCC lesions had lower ADC values (p = 0.029) than other RCC subtypes (clear cell or chromophobe). Diagnostic accuracy of DW-MRI for differentiation of papillary from non-papillary RCC was 70.3% resulting in a sensitivity and specificity of 64.3% (95% CI, 35.1–87.2) and 77.1 (95% CI, 59.9–89.6%). Accuracy increased to 83.7% in small renal masses (≤4 cm diameter) and sensitivity and specificity were 75.0% and 88.5%, respectively. The ADC values did not differ significantly between benign and malignant renal lesions (p = 0.45). Conclusions: DW-MRI seems to distinguish between papillary and other subtypes of RCCs especially in small renal masses but could not differentiate between benign and malignant renal lesions. Therefore, the use of DW-MRI for preoperative differentiation of renal lesions is limited

  16. Comparison of Pelvic Phased-Array versus Endorectal Coil Magnetic Resonance Imaging at 3 Tesla for Local Staging of Prostate Cancer

    OpenAIRE

    Kim, Bum Soo; Kim, Tae-Hwan; Kwon, Tae Gyun; Yoo, Eun Sang

    2012-01-01

    Purpose Several studies have demonstrated the superiority of endorectal coil magnetic resonance imaging (MRI) over pelvic phased-array coil MRI at 1.5 Tesla for local staging of prostate cancer. However, few have studied which evaluation is more accurate at 3 Tesla MRI. In this study, we compared the accuracy of local staging of prostate cancer using pelvic phased-array coil or endorectal coil MRI at 3 Tesla. Materials and Methods Between January 2005 and May 2010, 151 patients underwent radi...

  17. Comparison of Deep Brain Stimulation Lead Targeting Accuracy and Procedure Duration between 1.5-and 3-Tesla Interventional Magnetic Resonance Imaging Systems: An Initial 12-Month Experience

    OpenAIRE

    Southwell, DG; Narvid, JA; Martin, AJ; Qasim, SE; Starr, PA; Larson, PS

    2016-01-01

    Interventional magnetic resonance imaging (iMRI) allows deep brain stimulator lead placement under general anesthesia. While the accuracy of lead targeting has been described for iMRI systems utilizing 1.5-tesla magnets, a similar assessment of 3-tesla iMRI procedures has not been performed.To compare targeting accuracy, the number of lead targeting attempts, and surgical duration between procedures performed on 1.5- and 3-tesla iMRI systems.Radial targeting error, the number of targeting att...

  18. Fast 3D T1-weighted brain imaging at 3 Tesla with modified 3D FLASH sequence

    International Nuclear Information System (INIS)

    Longitudinal relaxation times (T1) of white and gray matter become close at high magnetic field. Therefore, classical T1 sensitive methods, like spoiled FLASH fail to give a sufficient contrast in human brain imaging at 3 Tesla. An excellent T1 contrast can be achieved at high field by gradient echo imaging with a preparatory inversion pulse. The inversion recovery (IR) preparation can be combined with a fast 2D gradient echo scans. In this paper we present an application of this technique to rapid 3-dimensional imaging. New technique called 3D SIR FLASH was implemented on Burker MSLX system equipped with a 3T, 90 cm horizontal bore magnet working in Centre Hospitalier in Rouffach, France. The new technique was used for comparison of MRI images of healthy volunteers obtained with a traditional 3D imaging. White and gray matter are clearly distinguishable when 3D SIR FLASH is used. The total acquisition time for 128x128x128 image was 5 minutes. Three dimensional visualization with facet representation of surfaces and oblique sections was done off-line on the INDIGO Extreme workstation. New technique is widely used in FORENAP, Centre Hospitalier in Reuffach, Alsace. (author)

  19. Sensitivity of an eight-element phased array coil in 3 Tesla MR imaging. A basic analysis

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the performance advantages of an 8-element phased array head coil (8 ch coil) over a conventional quadrature-type birdcage head coil (QD coil) with regard to the signal-to-noise ratio (SNR) and image uniformity in 3 Tesla magnetic resonance (MR) imaging. We scanned a phantom filled with silicon oil using an 8 ch coil and a QD coil in a 3T MR imaging system and compared the SNR and image uniformity obtained from T1-weighted spin echo (SE) images and T2-weighted fast SE images between the 2 coils. We also visually evaluated images from 4 healthy volunteers. The SNR with the 8 ch coil was approximately twice that with the QD coil in the region of interest (ROI), which was set as 75% of the area in the center of the phantom images. With regard to the spatial variation of sensitivity, the SNR with the 8 ch coil was lower at the center of the images than at the periphery, whereas the SNR with the QD coil exhibited an inverse pattern. At the center of the images with the 8 ch coil, the SNR was somewhat lower, and that distribution was relatively flat compared to that in the periphery. Image uniformity varied less with the 8 ch coil than with the QD coil on both imaging sequences. The 8 ch phased array coil was useful for obtaining high quality 3T images because of its higher SNR and improved image uniformity than those obtained with conventional quadrature-type birdcage head coil. (author)

  20. Initial results of 3-dimensional 1H-magnetic resonance spectroscopic imaging in the localization of prostate cancer at 3 Tesla: should we use an endorectal coil?

    NARCIS (Netherlands)

    Yakar, D.; Heijmink, S.W.T.P.J.; Hulsbergen- van de Kaa, C.A.; Huisman, H.J.; Barentsz, J.O.; Futterer, J.J.; Scheenen, T.W.J.

    2011-01-01

    PURPOSE: The purpose of this study was to compare the diagnostic performance of 3 Tesla, 3-dimensional (3D) magnetic resonance spectroscopic imaging (MRSI) in the localization of prostate cancer (PCa) with and without the use of an endorectal coil (ERC). MATERIALS AND METHODS: Our prospective study

  1. Comparison of increased venous contrast in ischemic stroke using phase-sensitive MR imaging with perfusion changes on flow-sensitive alternating inversion recovery at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Eijiro; Kanasaki, Yoshiko; Fujii, Shinya; Ogawa, Toshihide (Div. of Radiology, Dept. of Pathophysiological and Therapeutic Science, Faculty of Medicine, Tottori Univ. Hospital, Yonago, Tottori (Japan)), email: eyamashi-ttr@umin.ac.jp; Tanaka, Takuro; Hirata, Yoshiharu (Div. of Clinical Radiology, Tottori Univ. Hospital, Yonago, Tottori (Japan))

    2011-10-15

    Background Increased venous contrast in ischemic stroke using susceptibility-weighted imaging has been widely reported, although few reports have compared increased venous contrast areas with perfusion change areas. Purpose To compare venous contrast on phase-sensitive MR images (PSI) with perfusion change on flow-sensitive alternating inversion recovery (FAIR) images, and to discuss the clinical use of PSI in ischemic stroke. Material and Methods Thirty patients with clinically suspected acute infarction of the middle cerebral artery (MCA) territory within 7 days of onset were evaluated. Phase-sensitive imaging (PSI), flow-sensitive alternating inversion recovery (FAIR), diffusion-weighted imaging (DWI) and magnetic resonance angiography (MRA) were obtained using 3 Tesla scanner. Two neuroradiologists independently reviewed the MR images, as well as the PSI, DWI, and FAIR images. They were blinded to the clinical data and to each other's findings. The abnormal area of each image was ultimately identified after both neuroradiologists reached consensus. We analyzed areas of increased venous contrast on PSI, perfusion changes on FAIR images and signal changes on DWI for each case. Results Venous contrast increased on PSI and hypoperfusion was evident on FAIR images from 22 of the 30 patients (73%). The distribution of the increased venous contrast was the same as that of the hypoperfused areas on FAIR images in 16 of these 22. The extent of these lesions was larger than that of lesions visualized by on DWI in 18 of the 22 patients. Hypointense signals reflecting hemorrhage and no increased venous contrast on PSI and hyperperfusion on FAIR images were found in six of the remaining eight patients (20%). Findings on PSI were normal and hypoperfusion areas were absent on FAIR images of two patients (7%). Conclusion Increased venous contrast on PSI might serve as an index of misery perfusion and provide useful information

  2. Differences in Velopharyngeal Structure during Speech among Asians Revealed by 3-Tesla Magnetic Resonance Imaging Movie Mode

    Directory of Open Access Journals (Sweden)

    Kulthida Nunthayanon

    2015-01-01

    Full Text Available Objective. Different bony structures can affect the function of the velopharyngeal muscles. Asian populations differ morphologically, including the morphologies of their bony structures. The purpose of this study was to compare the velopharyngeal structures during speech in two Asian populations: Japanese and Thai. Methods. Ten healthy Japanese and Thai females (five each were evaluated with a 3-Tesla (3 T magnetic resonance imaging (MRI scanner while they produced vowel-consonant-vowel syllable (/asa/. A gradient-echo sequence, fast low-angle shot with segmented cine and parallel imaging technique was used to obtain sagittal images of the velopharyngeal structures. Results. MRI was carried out in real time during speech production, allowing investigations of the time-to-time changes in the velopharyngeal structures. Thai subjects had a significantly longer hard palate and produced shorter consonant than Japanese subjects. The velum of the Thai participants showed significant thickening during consonant production and their retroglossal space was significantly wider at rest, whereas the dimensional change during task performance was similar in the two populations. Conclusions. The 3 T MRI movie method can be used to investigate velopharyngeal function and diagnose velopharyngeal insufficiency. The racial differences may include differences in skeletal patterns and soft-tissue morphology that result in functional differences for the affected structures.

  3. Hip imaging of avascular necrosis at 7 Tesla compared with 3 Tesla

    International Nuclear Information System (INIS)

    To compare ultra-high field, high-resolution bilateral magnetic resonance imaging (MRI) of the hips at 7 Tesla (T) with 3 T MRI in patients with avascular necrosis (AVN) of the femoral head by subjective image evaluations, contrast measurements, and evaluation of the appearance of imaging abnormalities. Thirteen subjects with avascular necrosis treated using advanced core decompression underwent MRI at both 7 T and 3 T. Sequence parameters as well as resolution were kept identical for both field strengths. All MR images (MEDIC, DESS, PD/T2w TSE, T1w TSE, and STIR) were evaluated by two radiologists with regard to subjective image quality, soft tissue contrasts, B1 homogeneity (four-point scale, higher values indicating better image quality) and depiction of imaging abnormalities of the femoral heads (three-point scale, higher values indicating the superiority of 7 T). Contrast ratios of soft tissues were calculated and compared with subjective data. 7-T imaging of the femoral joints, as well as 3-T imaging, achieved ''good'' to ''very good'' quality in all sequences. 7 T showed significantly higher soft tissue contrasts for T2w and MEDIC compared with 3 T (cartilage/fluid: 2.9 vs 2.2 and 3.6 vs 2.6), better detailed resolution for cartilage defects (PDw, T2w, T1w, MEDIC, DESS > 2.5) and better visibility of joint effusions (MEDIC 2.6; PDw/T2w 2.4; DESS 2.2). Image homogeneity compared with 3 T (3.9-4.0 for all sequences) was degraded, especially in TSE sequences at 7 T through signal variations (7 T: 2.1-2.9); to a lesser extent also GRE sequences (7 T: 2.9-3.5). Imaging findings related to untreated or treated AVN were better delineated at 3 T (≤1.8), while joint effusions (2.2-2.6) and cartilage defects (2.5-3.0) were better visualized at 7 T. STIR performed much more poorly at 7 T, generating large contrast variations (1.5). 7-T hip MRI showed comparable results in hip joint imaging compared with 3 T with slight advantages in contrast detail (cartilage defects

  4. Comparison of three commercially available radio frequency coils for human brain imaging at 3 Tesla

    OpenAIRE

    Mekle, Ralf; Zwaag, Wietske van der; Joosten, Andreas; Gruetter, Rolf

    2008-01-01

    Objective To evaluate a transverse electromagnetic (TEM), a circularly polarized (CP) (birdcage), and a 12-channel phased array head coil at the clinical field strength of B (0) = 3T in terms of signal-to-noise ratio (SNR), signal homogeneity, and maps of the effective flip angle alpha.

  5. Diffusion-weighted imaging of breast tumours at 3 Tesla and 7 Tesla: a comparison

    International Nuclear Information System (INIS)

    To compare bilateral diffusion-weighted MR imaging (DWI) at 3 T and 7 T in the same breast tumour patients. Twenty-eight patients were included in this IRB-approved study (mean age 56 ± 16 years). Before contrast-enhanced imaging, bilateral DWI with b = 0 and 850 s/mm2 was performed in 2:56 min (3 T) and 3:48 min (7 T), using readout-segmented echo planar imaging (rs-EPI) with a 1.4 x 1.4 mm2 (3 T)/0.9 x 0.9 mm2 (7 T) in-plane resolution. Apparent diffusion coefficients (ADC), signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were assessed. Twenty-eight lesions were detected (18 malignant, 10 benign). CNR and SNR were comparable at both field strengths (p > 0.3). Mean ADC values at 7 T were 4-22 % lower than at 3 T (p ≤ 0.03). An ADC threshold of 1.275 x 10-3 mm2/s resulted in a diagnostic specificity of 90 % at both field strengths. The sensitivity was 94 % and 100 % at 3 T and 7 T, respectively. 7-T DWI of the breast can be performed with 2.4-fold higher spatial resolution than 3 T, without significant differences in SNR if compared to 3 T. (orig.)

  6. Diffusion-weighted imaging of breast tumours at 3 Tesla and 7 Tesla: a comparison

    Energy Technology Data Exchange (ETDEWEB)

    Gruber, S.; Minarikova, L.; Zaric, O.; Chmelik, M.; Strasser, B.; Trattnig, S.; Bogner, W. [Medical University Vienna, MRCE, Department of Biomedical imaging and Image-Guided Therapy, Vienna (Austria); Christian Doppler Laboratory for Clinical Molecular MR Imaging, Vienna (Austria); Pinker, K.; Baltzer, P.; Helbich, T. [Medical University Vienna, Division of Molecular and Gender Imaging, Department of Biomedical imaging and Image-Guided Therapy, Vienna (Austria)

    2016-05-15

    To compare bilateral diffusion-weighted MR imaging (DWI) at 3 T and 7 T in the same breast tumour patients. Twenty-eight patients were included in this IRB-approved study (mean age 56 ± 16 years). Before contrast-enhanced imaging, bilateral DWI with b = 0 and 850 s/mm{sup 2} was performed in 2:56 min (3 T) and 3:48 min (7 T), using readout-segmented echo planar imaging (rs-EPI) with a 1.4 x 1.4 mm{sup 2} (3 T)/0.9 x 0.9 mm{sup 2} (7 T) in-plane resolution. Apparent diffusion coefficients (ADC), signal-to-noise (SNR) and contrast-to-noise ratios (CNR) were assessed. Twenty-eight lesions were detected (18 malignant, 10 benign). CNR and SNR were comparable at both field strengths (p > 0.3). Mean ADC values at 7 T were 4-22 % lower than at 3 T (p ≤ 0.03). An ADC threshold of 1.275 x 10{sup -3} mm{sup 2}/s resulted in a diagnostic specificity of 90 % at both field strengths. The sensitivity was 94 % and 100 % at 3 T and 7 T, respectively. 7-T DWI of the breast can be performed with 2.4-fold higher spatial resolution than 3 T, without significant differences in SNR if compared to 3 T. (orig.)

  7. Parameters optimization of diffusion tensor MR imaging of the human calf at 3 tesla

    International Nuclear Information System (INIS)

    Objective: To demonstrate the feasibility of DTI in human calf with body phased-array coil and surface coil of spine as receiving coil on 3 T system, and to optimize the parameters of sequence, including slice thickness and b-value. Methods: Fifteen healthy volunteers were recruited in this study and randomly divided into three groups. The DTI sequence for head was performed on calf in the first group (5 cases), and the sequence parameters were optimized based on the deficits of the raw and the post-processed DTI images. Then, different slice thickness were applied in the senond group (5 cases) to optimize the slice thickness, and this optimized parameter with the highest score based on quality of the post-processed DTI images was applied in the next step. Finally, different b values were applied in the last group to optimize this parameters. The b value with the highest score based on the quality of the post-processed was the proper one. Results: Three problems existed in the raw and the post-processed images, when the DTI sequence for brain was used for the calf. First, the SNR of raw images is extremely low. Second, the muscle were unclear on the image with parts of signal lose, especially in the anterior tibialis muscle. Finally, the artifacts due to chemical shift and ghost are quite serious. The scores for muscle display quality with slice thickness of 4 mm, 5 mm and 6 mm were (7.0 ± 0.0), (8.6 ± 0.9) and (9.0 ± 0.0) score respectively, the signal loss scores were (5.0 ± 0.0) and (12.8 ± 2.6) and (13.8 ± 2.2) score respectively, and the general score were (22.0 ± 0.0) and (30.1 ± 3.8) and (31.0 ± 2.2) score respectively, and the general score were (22.0 ± 0.0) and (30.1 ± 3.8) and (31.0 ± 4.1) score respectively. The differences of above scores were significant among different slice thickness (F-value were 21.000 and 30.544 and 12.390 respectively, P2 were (9.0 ± 0.0), (14.0 ± 2.2) and (33.0 ± 2.2) score respectively, which were lower than

  8. Detailed imaging of the normal anatomy and pathologic conditions of the cavernous region at 3 Tesla using a contrast-enhanced MR angiography

    Energy Technology Data Exchange (ETDEWEB)

    Linn, Jennifer; Peters, Friederike; Lummel, Nina; Brueckmann, Hartmut; Yousry, Indra [University Hospital Munich, Department of Neuroradiology, Munich (Germany); Schankin, Christoph [University Hospital Munich, Department of Neurology, Munich (Germany); Rachinger, Walter [University Hospital Munich, Department of Neurosurgery, Munich (Germany)

    2011-12-15

    The purpose of this study was to evaluate the potential of a high-resolution contrast-enhanced magnetic resonance angiography (CE-MRA) at 3 Tesla for the delineation of the cavernous sinus (CS) anatomy both under normal and under pathological conditions. Fifteen patients without pathologies in the CS and ten patients with pituitary adenomas were included. The CE-MRA was performed on a 3-Tesla scanner and analyzed collaboratively by two readers. The cranial nerves (CNs) within the CS, namely CNIII, CNIV, CNV1, CNV2, and CNVI, were identified in both patient groups. In the adenoma patients it was also assessed whether and to which extend the adenoma invaded the CS and the spatial relationship between tumor and CNs was determined. In the patients with normal CS anatomy, CNIII could be identified in 100%, CNIV in 86.7%, and CNV1, CNV2, as well as CNVI in 100% of analyzed sides. Pituitary adenomas invaded the CS unilaterally (right side) in four patients, and bilaterally in six patients. In patients with adenomas, the CN could be identified and differentiated from the tumor in the following percentages: CNIII in 100%, CNIV in 70%, both CNV1 and CNV2 in 90%, and CNVI in 100%. In all these cases, the tumor-nerve spatial relationship could be visualized. 3-Tesla CE-MRA allows detailed imaging of the complex anatomy of the CS and its structures. In adenoma patients, it clearly visualizes the spatial relationship between tumor and CNs, and thus might be helpful to optimize presurgical planning. (orig.)

  9. Detailed imaging of the normal anatomy and pathologic conditions of the cavernous region at 3 Tesla using a contrast-enhanced MR angiography

    International Nuclear Information System (INIS)

    The purpose of this study was to evaluate the potential of a high-resolution contrast-enhanced magnetic resonance angiography (CE-MRA) at 3 Tesla for the delineation of the cavernous sinus (CS) anatomy both under normal and under pathological conditions. Fifteen patients without pathologies in the CS and ten patients with pituitary adenomas were included. The CE-MRA was performed on a 3-Tesla scanner and analyzed collaboratively by two readers. The cranial nerves (CNs) within the CS, namely CNIII, CNIV, CNV1, CNV2, and CNVI, were identified in both patient groups. In the adenoma patients it was also assessed whether and to which extend the adenoma invaded the CS and the spatial relationship between tumor and CNs was determined. In the patients with normal CS anatomy, CNIII could be identified in 100%, CNIV in 86.7%, and CNV1, CNV2, as well as CNVI in 100% of analyzed sides. Pituitary adenomas invaded the CS unilaterally (right side) in four patients, and bilaterally in six patients. In patients with adenomas, the CN could be identified and differentiated from the tumor in the following percentages: CNIII in 100%, CNIV in 70%, both CNV1 and CNV2 in 90%, and CNVI in 100%. In all these cases, the tumor-nerve spatial relationship could be visualized. 3-Tesla CE-MRA allows detailed imaging of the complex anatomy of the CS and its structures. In adenoma patients, it clearly visualizes the spatial relationship between tumor and CNs, and thus might be helpful to optimize presurgical planning. (orig.)

  10. Comparison of 3D cube FLAIR with 2D FLAIR for multiple sclerosis imaging at 3 tesla

    Energy Technology Data Exchange (ETDEWEB)

    Patzig, M.; Brueckmann, H.; Fesl, G. [Muenchen Univ. (Germany). Dept. of Neuroradiology; Burke, M. [GE Healthcare, Solingen (Germany)

    2014-05-15

    Purpose: Three-dimensional (3 D) MRI sequences allow improved spatial resolution with good signal and contrast properties as well as multiplanar reconstruction. We sought to compare Cube, a 3 D FLAIR sequence, to a standard 2 D FLAIR sequence in multiple sclerosis (MS) imaging. Materials and Methods: Examinations were performed in the clinical routine on a 3.0 Tesla scanner. 12 patients with definite MS were included. Lesions with MS-typical properties on the images of Cube FLAIR and 2 D FLAIR sequences were counted and allocated to different brain regions. Signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) were calculated. Results: With 384 the overall number of lesions found with Cube FLAIR was significantly higher than with 2 D FLAIR (N = 221). The difference was mostly accounted for by supratentorial lesions (N = 372 vs. N = 216) while the infratentorial lesion counts were low in both sequences. SNRs and CNRs were significantly higher in CUBE FLAIR with the exception of the CNR of lesion to gray matter, which was not significantly different. Conclusion: Cube FLAIR showed a higher sensitivity for MS lesions compared to a 2 D FLAIR sequence. 3 D FLAIR might replace 2 D FLAIR sequences in MS imaging in the future. (orig.)

  11. Comparison of 3D cube FLAIR with 2D FLAIR for multiple sclerosis imaging at 3 tesla

    International Nuclear Information System (INIS)

    Purpose: Three-dimensional (3 D) MRI sequences allow improved spatial resolution with good signal and contrast properties as well as multiplanar reconstruction. We sought to compare Cube, a 3 D FLAIR sequence, to a standard 2 D FLAIR sequence in multiple sclerosis (MS) imaging. Materials and Methods: Examinations were performed in the clinical routine on a 3.0 Tesla scanner. 12 patients with definite MS were included. Lesions with MS-typical properties on the images of Cube FLAIR and 2 D FLAIR sequences were counted and allocated to different brain regions. Signal-to-noise ratios (SNR) and contrast-to-noise ratios (CNR) were calculated. Results: With 384 the overall number of lesions found with Cube FLAIR was significantly higher than with 2 D FLAIR (N = 221). The difference was mostly accounted for by supratentorial lesions (N = 372 vs. N = 216) while the infratentorial lesion counts were low in both sequences. SNRs and CNRs were significantly higher in CUBE FLAIR with the exception of the CNR of lesion to gray matter, which was not significantly different. Conclusion: Cube FLAIR showed a higher sensitivity for MS lesions compared to a 2 D FLAIR sequence. 3 D FLAIR might replace 2 D FLAIR sequences in MS imaging in the future. (orig.)

  12. Coronary vessel-wall and lumen imaging using radial k-space acquisition with MRI at 3 Tesla

    International Nuclear Information System (INIS)

    This study investigates the feasibility of imaging the coronary lumen and vessel-wall, using MRI with a radial k-space trajectory at 3 T. Such radial trajectories offer the advantage of greater vessel sharpness than traditional Cartesian trajectories. This field strength offers an increased signal-to-noise ratio (SNR) compared with 1.5 T, which compensates for the slight SNR reduction due to the radial sequence. Images of the coronary lumen were acquired for seven healthy volunteers. In ten volunteers the vessel wall was scanned, with blood suppression using oblique-slab adiabatic re-inversion. Scans were performed during free breathing, using prospective respiratory navigator-gating. Coronary lumen scans had SNR of 16.0±1.9 and contrast-to-noise ratio (CNR) of 10.3±2.1, showing acceptable image quality. Vessel wall images showed good image quality, with mean SNR of 16.6±2.0/5.8±2.8/10.1±2.2 for vessel wall/lumen/epicardial fat. The wall-blood CNR was 10.7±2.7, and wall-fat CNR was 6.5±2.5. It is concluded that radial gradient-echo imaging at 3 T is a promising method for coronary vessel-wall imaging, and is also feasible for imaging the coronary lumen. (orig.)

  13. Investigation of Parallel Radiofrequency Transmission for the Reduction of Heating in Long Conductive Leads in 3 Tesla Magnetic Resonance Imaging.

    Directory of Open Access Journals (Sweden)

    Clare E McElcheran

    Full Text Available Deep Brain Stimulation (DBS is increasingly used to treat a variety of brain diseases by sending electrical impulses to deep brain nuclei through long, electrically conductive leads. Magnetic resonance imaging (MRI of patients pre- and post-implantation is desirable to target and position the implant, to evaluate possible side-effects and to examine DBS patients who have other health conditions. Although MRI is the preferred modality for pre-operative planning, MRI post-implantation is limited due to the risk of high local power deposition, and therefore tissue heating, at the tip of the lead. The localized power deposition arises from currents induced in the leads caused by coupling with the radiofrequency (RF transmission field during imaging. In the present work, parallel RF transmission (pTx is used to tailor the RF electric field to suppress coupling effects. Electromagnetic simulations were performed for three pTx coil configurations with 2, 4, and 8-elements, respectively. Optimal input voltages to minimize coupling, while maintaining RF magnetic field homogeneity, were determined for all configurations using a Nelder-Mead optimization algorithm. Resulting electric and magnetic fields were compared to that of a 16-rung birdcage coil. Experimental validation was performed with a custom-built 4-element pTx coil. In simulation, 95-99% reduction of the electric field at the tip of the lead was observed between the various pTx coil configurations and the birdcage coil. Maximal reduction in E-field was obtained with the 8-element pTx coil. Magnetic field homogeneity was comparable to the birdcage coil for the 4- and 8-element pTx configurations. In experiment, a temperature increase of 2±0.15°C was observed at the tip of the wire using the birdcage coil, whereas negligible increase (0.2±0.15°C was observed with the optimized pTx system. Although further research is required, these initial results suggest that the concept of optimizing p

  14. Investigation of Parallel Radiofrequency Transmission for the Reduction of Heating in Long Conductive Leads in 3 Tesla Magnetic Resonance Imaging.

    Science.gov (United States)

    McElcheran, Clare E; Yang, Benson; Anderson, Kevan J T; Golenstani-Rad, Laleh; Graham, Simon J

    2015-01-01

    Deep Brain Stimulation (DBS) is increasingly used to treat a variety of brain diseases by sending electrical impulses to deep brain nuclei through long, electrically conductive leads. Magnetic resonance imaging (MRI) of patients pre- and post-implantation is desirable to target and position the implant, to evaluate possible side-effects and to examine DBS patients who have other health conditions. Although MRI is the preferred modality for pre-operative planning, MRI post-implantation is limited due to the risk of high local power deposition, and therefore tissue heating, at the tip of the lead. The localized power deposition arises from currents induced in the leads caused by coupling with the radiofrequency (RF) transmission field during imaging. In the present work, parallel RF transmission (pTx) is used to tailor the RF electric field to suppress coupling effects. Electromagnetic simulations were performed for three pTx coil configurations with 2, 4, and 8-elements, respectively. Optimal input voltages to minimize coupling, while maintaining RF magnetic field homogeneity, were determined for all configurations using a Nelder-Mead optimization algorithm. Resulting electric and magnetic fields were compared to that of a 16-rung birdcage coil. Experimental validation was performed with a custom-built 4-element pTx coil. In simulation, 95-99% reduction of the electric field at the tip of the lead was observed between the various pTx coil configurations and the birdcage coil. Maximal reduction in E-field was obtained with the 8-element pTx coil. Magnetic field homogeneity was comparable to the birdcage coil for the 4- and 8-element pTx configurations. In experiment, a temperature increase of 2±0.15°C was observed at the tip of the wire using the birdcage coil, whereas negligible increase (0.2±0.15°C) was observed with the optimized pTx system. Although further research is required, these initial results suggest that the concept of optimizing pTx to reduce DBS

  15. Volume and asymmetry abnormalities of insula in antipsychotic-naive schizophrenia: A 3-Tesla magnetic resonance imaging study

    Directory of Open Access Journals (Sweden)

    Harve Shanmugam Virupaksha

    2012-01-01

    Full Text Available Context: Insula, which is a vital brain region for self-awareness, empathy, and sensory stimuli processing, is critically implicated in schizophrenia pathogenesis. Existing studies on insula volume abnormalities report inconsistent findings potentially due to the evaluation of ′antipsychotic-treated′ schizophrenia patients as well as suboptimal methodology. Aim: To understand the role of insula in schizophrenia. Materials and Methods: In this first-time 3-T magnetic resonance imaging study, we examined antipsychotic-naive schizophrenic patients (N=30 and age-, sex-, handedness- and education-matched healthy controls (N=28. Positive and negative symptoms were scored with good interrater reliability (intraclass correlation coefficient (ICC>0.9 by using the scales for negative and positive symptoms. Gray matter volume of insula and its anterior/posterior subregions were measured by using a three-dimensional, interactive, semiautomated software based on the valid method with good interrater reliability (ICC>0.85. Intracranial volume was automatically measured by using the FreeSurfer software. Results: Patients had significantly deficient gray matter volumes of left (F=33.4; Pleft in male patients in comparison with male controls (left>right (t=2.7; P=0.01. Conclusions: Robust insular volume deficits in antipsychotic-naive schizophrenia support intrinsic role for insula in pathogenesis of this disorder. The first-time demonstration of a relationship between right posterior insular deficit and negative symptoms is in tune with the background neurobiological literature. Another novel observation of sex-specific anterior insular asymmetry reversal in patients supports evolutionary postulates of schizophrenia pathogenesis.

  16. The Role of 3 Tesla Diffusion-Weighted Imaging in the Differential Diagnosis of Benign versus Malignant Cervical Lymph Nodes in Patients with Head and Neck Squamous Cell Carcinoma

    OpenAIRE

    Flavio Barchetti; Nicola Pranno; Guglielmo Giraldi; Alessandro Sartori; Silvia Gigli; Giovanni Barchetti; Luigi Lo Mele; Luigi Tonino Marsella

    2014-01-01

    Objective. The aim of this study was to validate the role of diffusion-weighted imaging (DWI) at 3 Tesla in the differential diagnosis between benign and malignant laterocervical lymph nodes in patients with head and neck squamous cell carcinoma (HNSCC). Materials and Methods. Before undergoing surgery, 80 patients, with biopsy proven HNSCC, underwent a magnetic resonance exam. Sensitivity (Se) and specificity (Spe) of conventional criteria and DWI in detecting laterocervical lymph node metas...

  17. Comparison of Brain Activation Images Associated with Sexual Arousal Induced by Visual Stimulation and SP6 Acupuncture: fMRI at 3 Tesla

    International Nuclear Information System (INIS)

    This study was performed not only to compare the brain activation regions associated with sexual arousal induced by visual stimulation and SP6 acupuncture, but also to evaluate its differential neuro-anatomical mechanism in healthy women using functional magnetic resonance imaging (fMRI) at 3 Tesla (T). A total of 21 healthy right-handed female volunteers (mean age 22 years, range 19 to 32) underwent fMRI on a 3T MR scanner. The stimulation paradigm for sexual arousal consisted of two alternating periods of rest and activation. It began with a 1-minute rest period, 3 minutes of stimulation with either of an erotic video film or SP6 acupuncture, followed by 1-minute rest. In addition, a comparative study on the brain activation patterns between an acupoint and a shampoint nearby GB37 was performed. The fMRI data were obtained from 20 slices parallel to the AC-PC line on an axial plane, giving a total of 2,000 images. The mean activation maps were constructed and analyzed by using the statistical parametric mapping (SPM99) software. As comparison with the shampoint, the acupoint showed 5 times and 2 times higher activities in the neocortex and limbic system, respectively. Note that brain activation in response to stimulation with the shampoint was not observed in the regions including the HTHL in the diencephalon, GLO and AMYG in the basal ganglia, and SMG in the parietal lobe. In the comparative study of visual stimulation vs. SP6 acupuncture, the mean activation ratio of stimulus was not significantly different to each other in both the neocortex and the limbic system (p < 0.05). The mean activities induced by both stimuli were not significantly different in the neocortex, whereas the acupunctural stimulation showed higher activity in the limbic system (p < 0.05). This study compared the differential brain activation patterns and the neural mechanisms for sexual arousal, which were induced by visual stimulation and SP6 acupuncture by using 3T fMRI. These findings

  18. Comparison of Brain Activation Images Associated with Sexual Arousal Induced by Visual Stimulation and SP6 Acupuncture: fMRI at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Nam Gil [Dept. of Radiology, Chonnam National University Hospital, Gwangju (Korea, Republic of); Han, Jae Bok; Jang, Seong Joo [Dept. of Radiology, Dongshin University, Naju (Korea, Republic of)

    2009-06-15

    This study was performed not only to compare the brain activation regions associated with sexual arousal induced by visual stimulation and SP6 acupuncture, but also to evaluate its differential neuro-anatomical mechanism in healthy women using functional magnetic resonance imaging (fMRI) at 3 Tesla (T). A total of 21 healthy right-handed female volunteers (mean age 22 years, range 19 to 32) underwent fMRI on a 3T MR scanner. The stimulation paradigm for sexual arousal consisted of two alternating periods of rest and activation. It began with a 1-minute rest period, 3 minutes of stimulation with either of an erotic video film or SP6 acupuncture, followed by 1-minute rest. In addition, a comparative study on the brain activation patterns between an acupoint and a shampoint nearby GB37 was performed. The fMRI data were obtained from 20 slices parallel to the AC-PC line on an axial plane, giving a total of 2,000 images. The mean activation maps were constructed and analyzed by using the statistical parametric mapping (SPM99) software. As comparison with the shampoint, the acupoint showed 5 times and 2 times higher activities in the neocortex and limbic system, respectively. Note that brain activation in response to stimulation with the shampoint was not observed in the regions including the HTHL in the diencephalon, GLO and AMYG in the basal ganglia, and SMG in the parietal lobe. In the comparative study of visual stimulation vs. SP6 acupuncture, the mean activation ratio of stimulus was not significantly different to each other in both the neocortex and the limbic system (p < 0.05). The mean activities induced by both stimuli were not significantly different in the neocortex, whereas the acupunctural stimulation showed higher activity in the limbic system (p < 0.05). This study compared the differential brain activation patterns and the neural mechanisms for sexual arousal, which were induced by visual stimulation and SP6 acupuncture by using 3T fMRI. These findings

  19. Breast MRI at 7 Tesla with a bilateral coil and T1-weighted acquisition with robust fat suppression: image evaluation and comparison with 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Ryan; Storey, Pippa; McGorty, KellyAnne; Klautau Leite, Ana Paula; Babb, James; Sodickson, Daniel K.; Wiggins, Graham C.; Moy, Linda [New York University Langone Medical Center, Bernard and Irene Schwartz Center for Biomedical Imaging, Department of Radiology, New York, NY (United States); Geppert, Christian [Siemens Medical Solutions USA Inc., New York, NY (United States)

    2013-11-15

    To evaluate the image quality of T1-weighted fat-suppressed breast MRI at 7 T and to compare 7-T and 3-T images. Seventeen subjects were imaged using a 7-T bilateral transmit-receive coil and 3D gradient echo sequence with adiabatic inversion-based fat suppression (FS). Images were graded on a five-point scale and quantitatively assessed through signal-to-noise ratio (SNR), fibroglandular/fat contrast and signal uniformity measurements. Image scores at 7 and 3 T were similar on standard-resolution images (1.1 x 1.1 x 1.1-1.6 mm{sup 3}), indicating that high-quality breast imaging with clinical parameters can be performed at 7 T. The 7-T SNR advantage was underscored on 0.6-mm isotropic images, where image quality was significantly greater than at 3 T (4.2 versus 3.1, P {<=} 0.0001). Fibroglandular/fat contrast was more than two times higher at 7 T than at 3 T, owing to effective adiabatic inversion-based FS and the inherent 7-T signal advantage. Signal uniformity was comparable at 7 and 3 T (P < 0.05). Similar 7-T image quality was observed in all subjects, indicating robustness against anatomical variation. The 7-T bilateral transmit-receive coil and adiabatic inversion-based FS technique produce image quality that is as good as or better than at 3 T. (orig.)

  20. Breast MRI at 7 Tesla with a bilateral coil and T1-weighted acquisition with robust fat suppression: image evaluation and comparison with 3 Tesla

    International Nuclear Information System (INIS)

    To evaluate the image quality of T1-weighted fat-suppressed breast MRI at 7 T and to compare 7-T and 3-T images. Seventeen subjects were imaged using a 7-T bilateral transmit-receive coil and 3D gradient echo sequence with adiabatic inversion-based fat suppression (FS). Images were graded on a five-point scale and quantitatively assessed through signal-to-noise ratio (SNR), fibroglandular/fat contrast and signal uniformity measurements. Image scores at 7 and 3 T were similar on standard-resolution images (1.1 x 1.1 x 1.1-1.6 mm3), indicating that high-quality breast imaging with clinical parameters can be performed at 7 T. The 7-T SNR advantage was underscored on 0.6-mm isotropic images, where image quality was significantly greater than at 3 T (4.2 versus 3.1, P ≤ 0.0001). Fibroglandular/fat contrast was more than two times higher at 7 T than at 3 T, owing to effective adiabatic inversion-based FS and the inherent 7-T signal advantage. Signal uniformity was comparable at 7 and 3 T (P < 0.05). Similar 7-T image quality was observed in all subjects, indicating robustness against anatomical variation. The 7-T bilateral transmit-receive coil and adiabatic inversion-based FS technique produce image quality that is as good as or better than at 3 T. (orig.)

  1. Incidental optochiasmatic cavernoma: Case report of an unusual finding on 3 Tesla MRI.

    Science.gov (United States)

    Trentadue, Mirko; Pozzi Mucelli, Roberto; Piovan, Enrico; Pizzini, Francesca Benedetta

    2016-08-01

    Cavernoma is a vascular hamartoma, which represents 10-20% of all central nervous system vascular malformations. The majority (80%) of them are supratentorial, while involvement of the cranial nerves and the optic pathways is extremely rare. The main clinical presentation of optochiasmatic cavernomas consists of chiasmatic apoplexy, which is a neurosurgical emergency. Here, we report a case in which the finding was incidentally detected in a 49-year-old man. We describe the imaging characteristics of the lesion in such a rare location, highlighting the role of magnetic resonance imaging (MRI) (specifically 3 Tesla) in the management of asymptomatic patients.

  2. Incidental optochiasmatic cavernoma: Case report of an unusual finding on 3 Tesla MRI.

    Science.gov (United States)

    Trentadue, Mirko; Pozzi Mucelli, Roberto; Piovan, Enrico; Pizzini, Francesca Benedetta

    2016-08-01

    Cavernoma is a vascular hamartoma, which represents 10-20% of all central nervous system vascular malformations. The majority (80%) of them are supratentorial, while involvement of the cranial nerves and the optic pathways is extremely rare. The main clinical presentation of optochiasmatic cavernomas consists of chiasmatic apoplexy, which is a neurosurgical emergency. Here, we report a case in which the finding was incidentally detected in a 49-year-old man. We describe the imaging characteristics of the lesion in such a rare location, highlighting the role of magnetic resonance imaging (MRI) (specifically 3 Tesla) in the management of asymptomatic patients. PMID:27145992

  3. Acute Posterior Ischemic Optic Neuropathy Mimicking Posterior Cerebral Artery Stroke Visualized by 3-Tesla MRI

    Directory of Open Access Journals (Sweden)

    Tilman Menzel

    2012-11-01

    Full Text Available Acute ischemic lesions of the posterior optic nerve and optic tract can produce a variety of visual field defects. A 71-year-old woman presented with acute hemianopia, which led to rt-PA thrombolysis for suspected posterior cerebral artery ischemia. 3-Tesla cMRI, however, revealed the cause to be an acute posterior ischemic optic neuropathy. Cases like this may be more common than thought and quite regularly overlooked in clinical practice, especially when there is no high-resolution MRI available. This case strengthens the importance of repeat MR imaging in patients with persistent visual field defects.

  4. Steady-state diffusion imaging for MR in-vivo evaluation of reparative cartilage after matrix-associated autologous chondrocyte transplantation at 3 tesla-Preliminary results

    International Nuclear Information System (INIS)

    Objectives: To demonstrate the feasibility of time-reversed fast imaging with steady-state precession (FISP) called PSIF for diffusion-weighted imaging of cartilage and cartilage transplants in a clinical study. Material and Methods: In a cross-sectional study 15 patients underwent MRI using a 3D partially balanced steady-state gradient echo pulse sequence with and without diffusion weighting at two different time points after matrix-associated autologous cartilage transplantation (MACT). Mean diffusion quotients (signal intensity without diffusion-weighting divided by signal intensity with diffusion weighting) within the cartilage transplants were compared to diffusion quotients found in normal cartilage. Results: The global diffusion quotient found in repair cartilage was significantly higher than diffusion values in normal cartilage (p < 0.05). There was a decrease between the earlier and the later time point after surgery. Conclusions: In-vivo diffusion-weighted imaging based on the PSIF technique is possible. Our preliminary results show follow-up of cartilage transplant maturation in patients may provide additional information to morphological assessment

  5. A novel receive-only liquid nitrogen (LN2)-cooled RF coil for high-resolution in vivo imaging on a 3-Tesla whole-body scanner

    OpenAIRE

    Hu, Bobo; Varma, Gopal; Randell, Chris; Keevil, Stephen F.; Schaeffter, Tobias; Glover, Paul

    2012-01-01

    The design and operation of a receive-only liquid nitrogen (LN2)-cooled coil and cryostat suitable for medical imaging on a 3-T whole-body magnetic resonance scanner is presented. The coil size, optimized for murine imaging, was determined by using electromagnetic (EM) simulations. This process is therefore easier and more cost effective than building a range of coils. A nonmagnetic cryostat suitable for small-animal imaging was developed having good vacuum and cryogenic temperature perform...

  6. Assessment of Safety and Interference Issues of Radio Frequency Identification Devices in 0.3 Tesla Magnetic Resonance Imaging and Computed Tomography

    OpenAIRE

    Periyasamy, M.; Dhanasekaran, R.

    2014-01-01

    The objective of this study was to evaluate two issues regarding magnetic resonance imaging (MRI) including device functionality and image artifacts for the presence of radio frequency identification devices (RFID) in association with 0.3 Tesla at 12.7 MHz MRI and computed tomography (CT) scanning. Fifteen samples of RFID tags with two different sizes (wristband and ID card types) were tested. The tags were exposed to several MR-imaging conditions during MRI examination and X-rays of CT scan....

  7. The Role of 3 Tesla Diffusion-Weighted Imaging in the Differential Diagnosis of Benign versus Malignant Cervical Lymph Nodes in Patients with Head and Neck Squamous Cell Carcinoma

    Science.gov (United States)

    Pranno, Nicola; Sartori, Alessandro; Gigli, Silvia; Lo Mele, Luigi; Marsella, Luigi Tonino

    2014-01-01

    Objective. The aim of this study was to validate the role of diffusion-weighted imaging (DWI) at 3 Tesla in the differential diagnosis between benign and malignant laterocervical lymph nodes in patients with head and neck squamous cell carcinoma (HNSCC). Materials and Methods. Before undergoing surgery, 80 patients, with biopsy proven HNSCC, underwent a magnetic resonance exam. Sensitivity (Se) and specificity (Spe) of conventional criteria and DWI in detecting laterocervical lymph node metastases were calculated. Histological results from neck dissection were used as standard of reference. Results. In the 239 histologically proven metastatic lymphadenopathies, the mean apparent diffusion coefficient (ADC) value was 0.903 × 10−3 mm2/sec. In the 412 pathologically confirmed benign lymph nodes, an average ADC value of 1.650 × 10−3 mm2/sec was found. For differentiating between benign versus metastatic lymph nodes, DWI showed Se of 97% and Spe of 93%, whereas morphological criteria displayed Se of 61% and Spe of 98%. DWI showed an area under the ROC curve (AUC) of 0.964, while morphological criteria displayed an AUC of 0.715. Conclusions. In a DWI negative neck for malignant lymph nodes, the planned dissection could be converted to a wait-and-scan policy, whereas DWI positive neck would support the decision to perform a neck dissection. PMID:25003115

  8. The Role of 3 Tesla Diffusion-Weighted Imaging in the Differential Diagnosis of Benign versus Malignant Cervical Lymph Nodes in Patients with Head and Neck Squamous Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Flavio Barchetti

    2014-01-01

    Full Text Available Objective. The aim of this study was to validate the role of diffusion-weighted imaging (DWI at 3 Tesla in the differential diagnosis between benign and malignant laterocervical lymph nodes in patients with head and neck squamous cell carcinoma (HNSCC. Materials and Methods. Before undergoing surgery, 80 patients, with biopsy proven HNSCC, underwent a magnetic resonance exam. Sensitivity (Se and specificity (Spe of conventional criteria and DWI in detecting laterocervical lymph node metastases were calculated. Histological results from neck dissection were used as standard of reference. Results. In the 239 histologically proven metastatic lymphadenopathies, the mean apparent diffusion coefficient (ADC value was 0.903 × 10−3 mm2/sec. In the 412 pathologically confirmed benign lymph nodes, an average ADC value of 1.650 × 10−3 mm2/sec was found. For differentiating between benign versus metastatic lymph nodes, DWI showed Se of 97% and Spe of 93%, whereas morphological criteria displayed Se of 61% and Spe of 98%. DWI showed an area under the ROC curve (AUC of 0.964, while morphological criteria displayed an AUC of 0.715. Conclusions. In a DWI negative neck for malignant lymph nodes, the planned dissection could be converted to a wait-and-scan policy, whereas DWI positive neck would support the decision to perform a neck dissection.

  9. Assessment of Safety and Interference Issues of Radio Frequency Identification Devices in 0.3 Tesla Magnetic Resonance Imaging and Computed Tomography

    Directory of Open Access Journals (Sweden)

    M. Periyasamy

    2014-01-01

    Full Text Available The objective of this study was to evaluate two issues regarding magnetic resonance imaging (MRI including device functionality and image artifacts for the presence of radio frequency identification devices (RFID in association with 0.3 Tesla at 12.7 MHz MRI and computed tomography (CT scanning. Fifteen samples of RFID tags with two different sizes (wristband and ID card types were tested. The tags were exposed to several MR-imaging conditions during MRI examination and X-rays of CT scan. Throughout the test, the tags were oriented in three different directions (axial, coronal, and sagittal relative to MRI system in order to cover all possible situations with respect to the patient undergoing MRI and CT scanning, wearing a RFID tag on wrist. We observed that the tags did not sustain physical damage with their functionality remaining unaffected even after MRI and CT scanning, and there was no alternation in previously stored data as well. In addition, no evidence of either signal loss or artifact was seen in the acquired MR and CT images. Therefore, we can conclude that the use of this passive RFID tag is safe for a patient undergoing MRI at 0.3 T/12.7 MHz and CT Scanning.

  10. Inter-study reproducibility of arterial spin labelling magnetic resonance imaging for measurement of renal perfusion in healthy volunteers at 3 Tesla

    OpenAIRE

    Gillis, Keith A.; McComb, Christie; Foster, John E.; Taylor, Alison; Patel, Rajan K.; Morris, Scott; Alan G. Jardine; Schneider, Markus P; Roditi, Giles H; Delles, Christian; Mark, Patrick B.

    2014-01-01

    Background: Measurement of renal perfusion is a crucial part of measuring kidney function. Arterial spin labelling magnetic resonance imaging (ASL MRI) is a non-invasive method of measuring renal perfusion using magnetised blood as endogenous contrast. We studied the reproducibility of ASL MRI in normal volunteers. Methods: ASL MRI was performed in healthy volunteers on 2 occasions using a 3.0 Tesla MRI scanner with flow-sensitive alternating inversion recovery (FAIR) perfusion prep...

  11. Dapsone improves functional deficit and diminishes brain damage evaluated by 3-Tesla magnetic resonance image after transient cerebral ischemia and reperfusion in rats.

    Science.gov (United States)

    Diaz-Ruiz, Araceli; Roldan-Valadez, Ernesto; Ortiz-Plata, Alma; Mondragón-Lozano, Rodrigo; Heras-Romero, Yessica; Mendez-Armenta, Marisela; Osorio-Rico, Laura; Nava-Ruiz, Concepción; Ríos, Camilo

    2016-09-01

    Stroke is a frequent cause of death and the first of disability in the world population. We have shown that dapsone acts as an antioxidant, antiinflammatory and antiapoptotic agent after brain Ischemia reperfusion (I/R) in rats; however, its therapeutic efficacy, measured by imaging has not been characterized. In this context, the aim of this study was to evaluate the neuroprotective effect of dapsone by magnetic resonance imaging (MRI) and to correlate imaging markers with motor function and oxidative stress after transient cerebral ischemia and reperfusion (I/R). We used male rats throughout the experiment. Functional deficit after I/R was assessed by using Longa scale. The area of brain tissue damage was measured by histology. The nuclear factor erythroid 2-related factor 2 (Nrf-2) and the amount of reactive oxygen species (ROS) were measured as biomarkers of oxidative stress. Finally, difussion tensor MRI was employed to measure the fractional anisotropy (FA), as a MRI marker of the pathophysiologic brain status. Results showed a better functional recovery and less damaged tissue in animals treated with dapsone vs control group. The values of FA were higher in animals receiving treatment, indicating a better preservation of brain structure. At early stages of the damage, dapsone was able to reduce both oxidative markers (Nrf-2 and ROS). Our findings provide new evidence for the efficacy of dapsone when administered during the acute phase after I/R and that quantitative sequences of MRI are useful for characterizing its potential therapeutic benefits after stroke. PMID:27321157

  12. Is the Susceptibility Vessel Sign on 3-Tesla Magnetic Resonance T2*-Weighted Imaging a Useful Tool to Predict Recanalization in Intravenous Tissue Plasminogen Activator?

    Science.gov (United States)

    Yamamoto, N; Satomi, J; Harada, M; Izumi, Y; Nagahiro, S; Kaji, R

    2016-09-01

    The aim of this study was to investigate the independent factors associated with the absence of recanalization approximately 24 h after intravenous administration of tissue-type plasminogen activator (IV TPA). The previous studies have been conducted using 1.5-Tesla (T) magnetic resonance imaging (MRI). We studied whether the characteristics of 3-T MRI findings were useful to predict outcome and recanalization after IV tPA. Patients with internal carotid artery (ICA) or middle cerebral artery (MCA) (horizontal portion, M1; Sylvian portion, M2) occlusion and treated by IV tPA were enrolled. We studied whether the presence of susceptibility vessel sign (SVS) at M1 and low clot burden score on T2*-weighted imaging (T2*-CBS) on 3-T MRI were associated with the absence of recanalization. A total of 49 patients were enrolled (27 men; mean age, 73.9 years). MR angiography obtained approximately 24 h after IV tPA revealed recanalization in 21 (42.9 %) patients. Independent factors associated with the absence of recanalization included ICA or proximal M1 occlusion (odds ratio, 69.6; 95 % confidence interval, 5.05-958.8, p = 0.002). In this study, an independent factor associated with the absence of recanalization may be proximal occlusion of the cerebral arteries rather than SVS in the MCA or low T2*-CBS on 3-T MRI.

  13. Molecular MRI differentiation between primary central nervous system lymphomas and high-grade gliomas using endogenous protein-based amide proton transfer MR imaging at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Shanshan [Southern Medical University, Department of Radiology, Zhujiang Hospital, Guangzhou, Guangdong (China); Johns Hopkins University School of Medicine, Department of Radiology, Baltimore, MD (United States); Yu, Hao; Wang, Xianlong; Lu, Shilong; Feng, Lyujin; Wen, Zhibo [Southern Medical University, Department of Radiology, Zhujiang Hospital, Guangzhou, Guangdong (China); Li, Yufa [Southern Medical University, Department of Pathology, Zhujiang Hospital, Guangzhou, Guangdong (China); Zhang, Yi; Heo, Hye-Young; Lee, Dong-Hoon; Zhou, Jinyuan [Johns Hopkins University School of Medicine, Department of Radiology, Baltimore, MD (United States)

    2016-01-15

    To show the ability of using the amide proton transfer-weighted (APTW) MRI signals as imaging biomarkers to differentiate primary central nervous system lymphomas (PCNSLs) from high-grade gliomas (HGGs). Eleven patients with lymphomas and 21 patients with HGGs were examined. Magnetization-transfer (MT) spectra over an offset range of ±6 ppm and the conventional MT ratio (MTR) at 15.6 ppm were acquired. The APTW signals, total chemical-exchange-saturation-transfer signal (integral between 0 and 5 ppm, CEST{sub total}), and MTR signal were obtained and compared between PCNSLs and HGGs. The diagnostic performance was assessed with the receiver operating characteristic (ROC) curve analysis. The PCNSLs usually showed more homogeneous APTW hyperintensity (spatially compared to normal brain tissue) than the HGGs. The APTW{sub max}, APTW{sub max-min} and CEST{sub total} signal intensities were significantly lower (P < 0.05, 0.001 and 0.05, respectively), while the APTW{sub min} and MTR were significantly higher (both P < 0.01) in PCNSL lesions than in HGG lesions. The APTW values in peritumoral oedema were significantly lower for PCNSLs than for HGGs (P < 0.01). APTW{sub max-min} had the highest area under the ROC curve (0.963) and accuracy (94.1 %) in differentiating PCNSLs from HGGs. The protein-based APTW signal would be a valuable MRI biomarker by which to identify PCNSLs and HGGs presurgically. (orig.)

  14. Interdependencies of aortic arch secondary flow patterns, geometry, and age analysed by 4-dimensional phase contrast magnetic resonance imaging at 3 Tesla

    International Nuclear Information System (INIS)

    It was the aim to analyse the impact of age, aortic arch geometry, and size on secondary flow patterns such as helix and vortex flow derived from flow-sensitive magnetic resonance imaging (4D PC-MRI). 62 subjects (age range = 20-80 years) without circumscribed pathologies of the thoracic aorta (ascending aortic (AAo) diameter: 3.2 ± 0.6 cm [range 2.2-5.1]) were examined by 4D PC-MRI after IRB-approval and written informed consent. Blood flow visualisation based on streamlines and time-resolved 3D particle traces was performed. Aortic diameter, shape (gothic, crook-shaped, cubic), angle, and age were correlated with existence and extent of secondary flow patterns (helicity, vortices); statistical modelling was performed. Helical flow was the typical pattern in standard crook-shaped aortic arches. With altered shapes and increasing age, helicity was less common. AAo diameter and age had the highest correlation (r = 0.69 and 0.68, respectively) with number of detected vortices. None of the other arch geometric or demographic variables (for all, P ≥ 0.177) improved statistical modelling. Substantially different secondary flow patterns can be observed in the normal thoracic aorta. Age and the AAo diameter were the parameters correlating best with presence and amount of vortices. Findings underline the importance of age- and geometry-matched control groups for haemodynamic studies. (orig.)

  15. Functional imaging of acute kidney injury at 3 Tesla. Investigating multiple parameters using DCE-MRI and a two-compartment filtration model

    Energy Technology Data Exchange (ETDEWEB)

    Zoellner, Frank G.; Zimmer, Fabian; Schad, Lothar R. [Heidelberg Univ., Mannheim (Germany). Computer Assisted Clinical Medicine; Klotz, Sarah; Hoeger, Simone [Heidelberg Univ., Mannheim (Germany). Dept. of Medicine V

    2015-05-01

    To investigate how MR-based parameters reflect functional changes in kidneys with acute kidney injury (AKI) using dynamic contrast enhanced MRI and a two-compartment renal filtration model. MRI data of eight male Lewis rats were analyzed retrospectively. Five animals were subjected to AKI, three native rats served as control. All animals underwent perfusion imaging by dynamic contrast-enhanced MRI. Renal blood volume, glomerular filtration rate (GFR) as well as plasma and tubular mean transit times were estimated from regions-of-interest drawn in the renal cortex. Differences between healthy kidneys and kidneys subjected to AKI were analyzed using a paired t-test. Significant differences between ischemic and healthy kidneys could only be detected for the glomerular filtration rate. For all other calculated parameters, differences were present, however not significant. In rats with AKI, average single kidney GFR was 0.66 ± 0.37 ml/min for contralateral and 0.26 ± 0.12 ml/ min for diseased kidneys (P = 0.0254). For the healthy control group, the average GFR was 0.39 ± 0.06 ml/min and 0.41 ± 0.11 ml/min, respectively. Differences between diseased kidneys of AKI rats and ipsilateral kidneys of the healthy control group were significant (P=0.0381). Significant differences of functional parameters reflecting damage of the renal tissue of kidneys with AKI compared to the contralateral, healthy kidneys could only be detected by GFR. GFR might be a useful parameter that allows for a spatially resolved detection of abnormal changes of renal tissue by AKI.

  16. Functional imaging of acute kidney injury at 3 Tesla. Investigating multiple parameters using DCE-MRI and a two-compartment filtration model

    International Nuclear Information System (INIS)

    To investigate how MR-based parameters reflect functional changes in kidneys with acute kidney injury (AKI) using dynamic contrast enhanced MRI and a two-compartment renal filtration model. MRI data of eight male Lewis rats were analyzed retrospectively. Five animals were subjected to AKI, three native rats served as control. All animals underwent perfusion imaging by dynamic contrast-enhanced MRI. Renal blood volume, glomerular filtration rate (GFR) as well as plasma and tubular mean transit times were estimated from regions-of-interest drawn in the renal cortex. Differences between healthy kidneys and kidneys subjected to AKI were analyzed using a paired t-test. Significant differences between ischemic and healthy kidneys could only be detected for the glomerular filtration rate. For all other calculated parameters, differences were present, however not significant. In rats with AKI, average single kidney GFR was 0.66 ± 0.37 ml/min for contralateral and 0.26 ± 0.12 ml/ min for diseased kidneys (P = 0.0254). For the healthy control group, the average GFR was 0.39 ± 0.06 ml/min and 0.41 ± 0.11 ml/min, respectively. Differences between diseased kidneys of AKI rats and ipsilateral kidneys of the healthy control group were significant (P=0.0381). Significant differences of functional parameters reflecting damage of the renal tissue of kidneys with AKI compared to the contralateral, healthy kidneys could only be detected by GFR. GFR might be a useful parameter that allows for a spatially resolved detection of abnormal changes of renal tissue by AKI.

  17. A free-breathing non-contrast-enhanced pulmonary magnetic resonance angiography at 3 Tesla

    Institute of Scientific and Technical Information of China (English)

    YANG Jian; WANG Wei; WANG Ya-rong; NIU Gang; JIN Chen-wang; WU Ed Xuekui

    2009-01-01

    Background The breathhold contrast-enhanced three-dimensional magnetic resonance angiography (MRA) using T1-weighted gradient-echo imaging sequence is the standard technique for MRA of the thorax. However, this technique is not desirable for certain patients with respiratory insufficiency, serious renal impairment, or allergy to contrast agents. The objective of this study was to optimize and evaluate a non-contrast-enhanced free-breathing pulmonary MRA protocol at 3 Tesla.Methods The time-of-flight protocol was based on a two-dimensional T1-weighted turbo field echo sequence with slice-selective inversion recovery and magnetization transfer preparation together with respiratory navigator gating, cardiac gating, and parallel imaging. Optimal values for time of inversion delay, flip angle and slice thickness were experimentally determined and used for all subjects.Results Excellent pulmonary MRA images, in which the 7th order branches of pulmonary arteries could be reliably identified, were obtained in the 12 free-breathing healthy volunteers. TI of ~300 ms provides the best suppression of background thoracic and cardiac muscles and effective inflow enhancement. With increasing flip angle, the pulmonary vessels gradually brightened and exhibited optimal contrast at 20°-30°. The 2 mm slice thickness and 0.5 mm slice overlap is suitable for visualization of the peripheral pulmonary vessel.Conclusions The MRA protocol at 3 Tesla may have clinical significance for pulmonary vascular imaging in patients who are not available for contrast-enhanced 3D MRA and CT angiography examination or are unable to sustain a long breath-hold.

  18. Rapid parametric mapping of the longitudinal relaxation time T1 using two-dimensional variable flip angle magnetic resonance imaging at 1.5 Tesla, 3 Tesla, and 7 Tesla.

    Directory of Open Access Journals (Sweden)

    Matthias A Dieringer

    Full Text Available INTRODUCTION: Visual but subjective reading of longitudinal relaxation time (T1 weighted magnetic resonance images is commonly used for the detection of brain pathologies. For this non-quantitative measure, diagnostic quality depends on hardware configuration, imaging parameters, radio frequency transmission field (B1+ uniformity, as well as observer experience. Parametric quantification of the tissue T1 relaxation parameter offsets the propensity for these effects, but is typically time consuming. For this reason, this study examines the feasibility of rapid 2D T1 quantification using a variable flip angles (VFA approach at magnetic field strengths of 1.5 Tesla, 3 Tesla, and 7 Tesla. These efforts include validation in phantom experiments and application for brain T1 mapping. METHODS: T1 quantification included simulations of the Bloch equations to correct for slice profile imperfections, and a correction for B1+. Fast gradient echo acquisitions were conducted using three adjusted flip angles for the proposed T1 quantification approach that was benchmarked against slice profile uncorrected 2D VFA and an inversion-recovery spin-echo based reference method. Brain T1 mapping was performed in six healthy subjects, one multiple sclerosis patient, and one stroke patient. RESULTS: Phantom experiments showed a mean T1 estimation error of (-63±1.5% for slice profile uncorrected 2D VFA and (0.2±1.4% for the proposed approach compared to the reference method. Scan time for single slice T1 mapping including B1+ mapping could be reduced to 5 seconds using an in-plane resolution of (2×2 mm2, which equals a scan time reduction of more than 99% compared to the reference method. CONCLUSION: Our results demonstrate that rapid 2D T1 quantification using a variable flip angle approach is feasible at 1.5T/3T/7T. It represents a valuable alternative for rapid T1 mapping due to the gain in speed versus conventional approaches. This progress may serve to enhance

  19. Image distortion and artifacts caused by the use of a titanium aneurism clip in 1.5 tesla- and 3 tesla-magnetic resonance imaging. Effect on 60Cobalt stereotactic radiosurgery treatment planning

    International Nuclear Information System (INIS)

    In gamma knife stereotactic radiosurgery (GKSRS) treatment planning, 1.5 tesla (T)-magnetic resonance imaging (MRI) is normally used to identify the target lesion. Image artifacts and distortion arise in MRI if a titanium clip is surgically implanted in the brain to treat cerebral aneurysm. 3-T MRI scanners, which are increasingly being adopted, provide imaging of anatomic structures with better clinical usefulness than 1.5-T MRI machines. We investigated signal defects and image distortions both close to and more distant from the titanium clip in 1.5-T and 3-T MRI. Two kinds of phantoms were scanned using 1.5-T and 3-T MRI. Acquisitions with and without the clip were performed under the same scan parameters. No difference was observed between 1.5 T and 3 T in local decrease of signal intensity; however, image distortion was observed at 20 mm from the clip in 3 T. Over the whole region, the distortions caused by the clip were less than 0.3 mm and 1.6 mm under 1.5-T and 3-T MRI, respectively. The geometric accuracy of 1.5-T MRI was better than 3-T MRI and thus better for GKSRS treatment planning. 3-T MRI, however, appears less suitable for use in treatment planning. (author)

  20. Dobutamine stress cardiovascular magnetic resonance at 3 Tesla

    Directory of Open Access Journals (Sweden)

    Klein C

    2008-10-01

    Full Text Available Abstract Purpose The assessment of inducible wall motion abnormalities during high-dose dobutamine-stress cardiovascular magnetic resonance (DCMR is well established for the identification of myocardial ischemia at 1.5 Tesla. Its feasibility at higher field strengths has not been reported. The present study was performed to prospectively determine the feasibility and diagnostic accuracy of DCMR at 3 Tesla for depicting hemodynamically significant coronary artery stenosis (≥ 50% diameter stenosis in patients with suspected or known coronary artery disease (CAD. Materials and methods Thirty consecutive patients (6 women (66 ± 9.3 years were scheduled for DCMR between January and May 2007 for detection of coronary artery disease. Patients were examined with a Philips Achieva 3 Tesla system (Philips Healthcare, Best, The Netherlands, using a spoiled gradient echo cine sequence. Technical parameters were: spatial resolution 2 × 2 × 8 mm3, 30 heart phases, spoiled gradient echo TR/TE: 4.5/2.6 msec, flip angle 15°. Images were acquired at rest and stress in accordance with a standardized high-dose dobutamine-atropine protocol during short breath-holds in three short and three long-axis views. Dobutamine was administered using a standard protocol (10 μg increments every 3 minutes up to 40 μg dobutamine/kg body weight/minute plus atropine if required to reach target heart rate. The study protocol included administration of 0.1 mmol/kg/body weight Gd-DTPA before the cine images at rest were acquired to improve the image quality. The examination was terminated if new or worsening wall-motion abnormalities or chest pain occurred or when > 85% of age-predicted maximum heart rate was reached. Myocardial ischemia was defined as new onset of wall-motion abnormality in at least one segment. In addition, late gadolinium enhancement (LGE was performed. Images were evaluated by two blinded readers. Diagnostic accuracy was determined with coronary

  1. Double-bundle depiction of the anterior cruciate ligament at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Adriaensen, M.E.A.P.M. [Atrium Medical Center Parkstad, Department of Radiology, Heerlen (Netherlands); Hogan, B. [Sports Surgery Clinic, Department of Radiology, Dublin (Ireland); Al-Bulushi, H.I.J. [Armed Forces Hospital, Department of Radiology, Muscat (Oman); Kavanagh, E.C. [Mater Misericordiae Hospital, Department of Radiology, Dublin (Ireland)

    2012-07-15

    Magnetic resonance imaging on 3 Tesla (3T MRI) with arthroscopic correlation has proven to adequately identify the anteromedial bundle (AMB) and posterolateral bundle (PLB) in cadaver knees. The purpose of this study was to describe the depiction of ACL bundle anatomy on 3T MRI in daily practice. In a retrospective cohort study, we included 50 consecutive patients who underwent standard 3T MRI of the knee and had an intact ACL. Two musculoskeletal radiologists independently reviewed all scans for depiction of ACL bundle anatomy using standardized forms. Descriptive statistics were used. Twenty-three right knees (46%) and 27 left knees (54%) were included in the study. Mean age of the patients was 35 years (range 12 to 68 years); 37 patients were male (74%). ACL bundle anatomy was best depicted in the axial plane in 44 knees (88%) and in the coronal plane in six knees (12%). Two bundles were seen in 47 knees (94%). The AMB was completely seen in 45 knees (90%). The PLB was completely seen in 40 knees (80%). Both bundles were completely seen in 37 knees (76%). The double-bundle anatomy of the ACL is visualized in 94% of patients on 3T MRI. Because of potentially associated clinical benefits, we advocate to report separately on the anteromedial bundle and posterolateral bundle in case of anterior cruciate ligament injury of the knee. (orig.)

  2. A Novel 16-Channel Receive Coil Array for Accelerated Upper Airway MRI at 3 Tesla

    OpenAIRE

    Kim, Yoon-Chul; Hayes, Cecil E.; Narayanan, Shrikanth S.; Nayak, Krishna S.

    2010-01-01

    Upper airway MRI provides a non-invasive assessment of speech and swallowing disorders and sleep apnea. Recent work has demonstrated the value of high-resolution three-dimensional (3D) imaging and dynamic 2D imaging and the importance of further improvements in spatio-temporal resolution. The purpose of the study was to describe a novel 16-channel 3 Tesla receive coil that is highly sensitive to the human upper airway and investigate the performance of accelerated upper airway MRI with the co...

  3. Acute Posterior Ischemic Optic Neuropathy Mimicking Posterior Cerebral Artery Stroke Visualized by 3-Tesla MRI

    OpenAIRE

    Menzel, Tilman; Kern, Rolf; Griebe, Martin; Hennerici, Michael; Fatar, Marc

    2012-01-01

    Acute ischemic lesions of the posterior optic nerve and optic tract can produce a variety of visual field defects. A 71-year-old woman presented with acute hemianopia, which led to rt-PA thrombolysis for suspected posterior cerebral artery ischemia. 3-Tesla cMRI, however, revealed the cause to be an acute posterior ischemic optic neuropathy. Cases like this may be more common than thought and quite regularly overlooked in clinical practice, especially when there is no high-resolution MRI avai...

  4. Rapid parametric mapping of the longitudinal relaxation time t1 using two-dimensional variable flip angle magnetic resonance imaging at 1.5 Tesla, 3 Tesla, and 7 Tesla

    OpenAIRE

    Dieringer, Matthias A; Michael Deimling; Davide Santoro; Jens Wuerfel; Vince I Madai; Jan Sobesky; Florian von Knobelsdorff-Brenkenhoff; Jeanette Schulz-Menger; Thoralf Niendorf

    2014-01-01

    Introduction Visual but subjective reading of longitudinal relaxation time (T1) weighted magnetic resonance images is commonly used for the detection of brain pathologies. For this non-quantitative measure, diagnostic quality depends on hardware configuration, imaging parameters, radio frequency transmission field (B1 + ) uniformity, as well as observer experience. Parametric quantification of the tissue T1 relaxation parameter offsets the propensity for these effects, but is typically time c...

  5. Early Choline Levels From 3-Tesla MR Spectroscopy After Exclusive Radiation Therapy in Patients With Clinically Localized Prostate Cancer are Predictive of Plasmatic Levels of PSA at 1 Year

    International Nuclear Information System (INIS)

    Purpose: To investigate the time course response of prostate metabolism to irradiation using magnetic resonance spectroscopy (MRS) at 3-month intervals and its impact on biochemical control. Methods and Materials: Between January 2008 and April 2010, 24 patients with localized prostate cancer were prospectively enrolled in the Evaluation of the Response to Irradiation with MR Spectroscopy (ERIS) trial. All the patients had been treated with intensity-modulated radiation therapy with or without long-term adjuvant hormonal therapy (LTHT) and underwent 3-T MRS and prostate-specific antigen (PSA) assays at baseline and every 3 months thereafter up to 12 months. Results: After radiation, the mean normalized citrate level (citrate/water) decreased significantly over time, both in the peripheral zone (PZ) (p = 0.0034) and in the entire prostate (p = 0.0008), whereas no significant change was observed in mean normalized choline levels (choline/water) in the PZ (p = 0.84) and in the entire prostate (p = 0.95). At 6 months after radiation, the mean choline level was significantly lower in the PZ for patients with a PSA value of ≤0.5 ng/mL at 12 months (4.9 ± 1.7 vs. 7.1 ± 1.5, p = 0.0378). Similar results were observed at 12 months in the PZ (6.2 ± 2.3 vs. 11.4 ± 4.1, p = 0.0117 for choline level and 3.4 ± 0.7 vs. 16.1 ± 6.1, p = 0.0054 for citrate level) and also in the entire prostate (6.2 ± 1.9 vs. 10.4 ± 3.2, p = 0.014 for choline level and 3.0 ± 0.8 vs. 13.3 ± 4.7, p = 0.0054 for citrate level). For patients receiving LTHT, there was no correlation between choline or citrate levels and PSA value, either at baseline or at follow-up. Conclusions: Low normalized choline in the PZ, 6 months after radiation, predicts which patients attained a PSA ≤0.5 ng/mL at 1 year. Further analyses with longer follow-up times are warranted to determine whether or not these new biomarkers can conclusively predict the early radiation response and the clinical outcome for

  6. 正常人小腿肌肉3 T MR扩散张量成像的参数优化%Parameters optimization of diffusion tensor MR imaging of the human calf at 3 tesla

    Institute of Scientific and Technical Information of China (English)

    邓德茂; 潘碧涛; 黎燕宁; 孟悛非; 张朝晖; 马立恒; 周春香; 高振华; 张小玲; 马玲; 林尔坚

    2009-01-01

    Objective To demonstrate the feasibility of DTI in human calf with body phased-array coil and surface coil of spine as receiving coil on 3 T system, and to optimize the parameters of sequence, including slice thickness and b-value. Methods Fifteen healthy volunteers were recruited in this study and randomly divided into three groups. The DTI sequence for head was performed on calf in the first group (5 cases), and the sequence parameters were optimized based on the deficits of the raw and the post-processed DTI images. Then, different slice thickness were applied in the senond group (5 eases) to optimize the slice thickness, and this optimized parameter with the highest score based on quality of the post-processed DTI images was applied in the next step. Finally, different b values were applied in the last group to optimize this parameters. The b value with the highest score based on the quality of the pest-processed was the proper one. Results Three problems existed in the raw and the pest-processed images, when the DTI sequence for brain was used for the calf. First, the SNR of raw images is extremely low. Second, the muscle were unclear on the image with parts of signal lose, especially in the anterior tibialis muscle. Finally, the artifacts due to chemical shift and ghost are quite serious. The scores for muscle display quality with slice thickness of 4 mm , 5 mm and 6 mm were (7.0±0. 0), (8.6±0. 9) and (9.0±0. 0) score respectively, the signal less scores were (5.0±0. 0) and ( 12. 8±2. 6) and ( 13. 8±2. 2) score respectively, and the general score were (22. 0±0. 0) and (30. 1±3.8) and (31.0±4. 1 ) score respectively. The differences of above scores were significant among different slice thickness (F-value were 21. 000 and 30. 544 and 12. 390 respectively, P 0. 05 ). Conclusion Our preliminary findings indicate that it is feasible to perform DTI on human calf with 3 T MR. With body phased-array coil and surface coil of spine as receiving coil, the DTI

  7. Flow-sensitive in-vivo 4D MR imaging at 3T for the analysis of aortic hemodynamics and derived vessel wall parameters; Die Analyse aortaler Haemodynamik und Gefaesswandparameter mittels fluss-sensitiver in-vivo 4D-MRT bei 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Frydrychowicz, A.; Markl, M.; Stalder, A.F.; Bock, J.; Bley, T.A.; Berger, A.; Russe, M.F.; Hennig, J.; Langer, M. [Freiburg Univ. (Germany). Abt. Roentgendiagnostik; Harloff, A. [Freiburg Univ. (Germany). Abt. Klinische Neurologie und Neurophysiologie; Schlensak, C. [Freiburg Univ. (Germany). Abt. Herz- und Gefaesschirurgie

    2007-05-15

    Modern phase contrast MR imaging at 3 Tesla allows the depiction of 3D morphology as well as the acquisition of time-resolved blood flow velocities in 3 directions. In combination with state-of-the-art visualization and data processing software, the qualitative and quantitative analysis of hemodynamic changes associated with vascular pathologies is possible. The 4D nature of the acquired data permits free orientation within the vascular system of interest and offers the opportunity to quantify blood flow and derived vessel wall parameters at any desired location within the data volume without being dependent on predefined 2D slices. The technique has the potential of overcoming the limitations of current diagnostic strategies and of implementing new diagnostic parameters. In light of the recent discussions regarding the influence of the wall shear stress and the oscillatory shear index on the genesis of arteriosclerosis and dilatative vascular processes, flow-sensitive 4D MRI may provide the missing diagnostic link. Instead of relying on experience-based parameters such as aneurysm size, new hemodynamic considerations can deepen our understanding of vascular pathologies. This overview reviews the underlying methodology at 3T, the literature on time-resolved 3D MR velocity mapping, and presents case examples. By presenting the pre- and postoperative assessment of hemodynamics in a thoracic aortic aneurysm and the detailed analysis of blood flow in a patient with coarctation we underline the potential of time-resolved 3D phase contrast MR at 3T for hemodynamic assessment of vascular pathologies, especially in the thoracic aorta. (orig.)

  8. Ventricular Assist Device implant (AB 5000 prototype cannula: In vitro assessment of MRI issues at 3-Tesla

    Directory of Open Access Journals (Sweden)

    Valencerina Samuel

    2008-05-01

    Full Text Available Abstract Purpose To evaluate MRI issues at 3-Tesla for a ventricular assist device (VAD. Methods The AB5000 Ventricle with a prototype Nitinol wire-reinforced In-Flow Cannula and Out-Flow Cannula attached (Abiomed, Inc., Danvers, MA was evaluated for magnetic field interactions, heating, and artifacts at 3-Tesla. MRI-related heating was assessed with the device in a gelled-saline-filled, head/torso phantom using a transmit/received RF body coil while performing MRI at a whole body averaged SAR of 3-W/kg for 15-min. Artifacts were assessed for the main metallic component of this VAD (atrial cannula using T1-weighted, spin echo and gradient echo pulse sequences. Results The AB5000 Ventricle with the prototype In-Flow Cannula and Out-Flow Cannula attached showed relatively minor magnetic field interactions that will not cause movement in situ. Heating was not excessive (highest temperature change, +0.8°C. Artifacts may create issues for diagnostic imaging if the area of interest is in the same area or close to the implanted metallic component of this VAD (i.e., the venous cannula. Conclusion The results of this investigation demonstrated that it would be acceptable for a patient with this VAD (AB5000 Ventricle with a prototype Nitinol wire-reinforced In-Flow Cannula and Out-Flow Cannula attached to undergo MRI at 3-Tesla or less. Notably, it is likely that the operation console for this device requires positioning a suitable distance (beyond the 100 Gauss line or in the MR control room from the 3-Tesla MR system to ensure proper function of the VAD.

  9. High-resolution motion compensated MRA in patients with congenital heart disease using extracellular contrast agent at 3 Tesla

    Directory of Open Access Journals (Sweden)

    Dabir Darius

    2012-10-01

    Full Text Available Abstract Background Using first-pass MRA (FP-MRA spatial resolution is limited by breath-hold duration. In addition, image quality may be hampered by respiratory and cardiac motion artefacts. In order to overcome these limitations an ECG- and navigator-gated high-resolution-MRA sequence (HR-MRA with slow infusion of extracellular contrast agent was implemented at 3 Tesla for the assessment of congenital heart disease and compared to standard first-pass-MRA (FP-MRA. Methods 34 patients (median age: 13 years with congenital heart disease (CHD were prospectively examined on a 3 Tesla system. The CMR-protocol comprised functional imaging, FP- and HR-MRA, and viability imaging. After the acquisition of the FP-MRA sequence using a single dose of extracellular contrast agent the motion compensated HR-MRA sequence with isotropic resolution was acquired while injecting the second single dose, utilizing the timeframe before viability imaging. Qualitative scores for image quality (two independent reviewers as well as quantitative measurements of vessel sharpness and relative contrast were compared using the Wilcoxon signed-rank test. Quantitative measurements of vessel diameters were compared using the Bland-Altman test. Results The mean image quality score revealed significantly better image quality of the HR-MRA sequence compared to the FP-MRA sequence in all vessels of interest (ascending aorta (AA, left pulmonary artery (LPA, left superior pulmonary vein (LSPV, coronary sinus (CS, and coronary ostia (CO; all p  Conclusions An ECG- and navigator-gated HR-MRA-protocol with infusion of extracellular contrast agent at 3 Tesla is feasible. HR-MRA delivers significantly better image quality and vessel sharpness compared to FP-MRA. It may be integrated into a standard CMR-protocol for patients with CHD without the need for additional contrast agent injection and without any additional examination time.

  10. Initial Experience of 3-Tesla Apparent Diffusion Coefficient Values in Characterizing Squamous Cell Carcinomas of the Head and Neck

    International Nuclear Information System (INIS)

    Background: With the increased clinical use of 3-Tesla (3T) magnets, it becomes important to identify the potential applications of advanced magnetic resonance (MR) imaging techniques such as diffusion-weighted imaging in head and neck pathologies. Purpose: To establish the 3T apparent diffusion coefficient (ADC) values for normal neck structures, and to examine the utility of ADC values in distinguishing head and neck squamous cell carcinomas (HNSCC) from normal neck anatomy. Material and Methods: 3T diffusion-weighted imaging was performed on 10 normal volunteers and 10 patients with known HNSCC. In the volunteers, mean ADC was calculated in the parotid gland, submandibular gland, base of the tongue, pterygoid muscle, masseter muscle, paraspinal muscles, true vocal cord, thyroid gland, thyroid cartilage, cricoid cartilage, and lymph nodes. The mean tumor ADC value was calculated from the 10 patients with HNSCC and compared with the normal ADC values from various neck structures. Results: The mean ADC value measured in the HNSCC was 1.101 (±0.214)x10-3mm2/s. This was significantly lower than ADC values of paraspinal muscles, pterygoid muscle, masseter muscle, thyroid gland, and base of the tongue (P=0.0006, 0.0002, 0.0001, 0.001, and 0.002, respectively). The tumor ADC values were not significantly different from ADC values of parotid and submandibular glands (P=0.057 and 0.14, respectively). Conclusion: 3T ADC values show potential for distinguishing HNSCC from normal extracranial head and neck structures

  11. Diagnostic accuracy of a short-duration 3 Tesla magnetic resonance protocol for diagnosing stifle joint lesions in dogs with non-traumatic cranial cruciate ligament rupture

    OpenAIRE

    Galindo-Zamora, Vladimir; Dziallas, Peter; Ludwig, Davina C; Nolte, Ingo; Wefstaedt, Patrick

    2013-01-01

    Background Magnetic resonance (MR) imaging is the preferred diagnostic tool to evaluate internal disorders of many joints in humans; however, the usefulness of MR imaging in the context of osteoarthritis, and joint disease in general, has yet to be characterized in veterinary medicine. The objective of this study was to assess the diagnostic accuracy of short-duration 3 Tesla MR imaging for the evaluation of cranial and caudal cruciate ligament, meniscal and cartilage damage, as well as the d...

  12. Resection and Resolution of Bone Marrow Lesions Associated with an Improvement of Pain after Total Knee Replacement: A Novel Case Study Using a 3-Tesla Metal Artefact Reduction MRI Sequence.

    Science.gov (United States)

    Kurien, Thomas; Kerslake, Robert; Haywood, Brett; Pearson, Richard G; Scammell, Brigitte E

    2016-01-01

    We present our case report using a novel metal artefact reduction magnetic resonance imaging (MRI) sequence to observe resolution of subchondral bone marrow lesions (BMLs), which are strongly associated with pain, in a patient after total knee replacement surgery. Large BMLs were seen preoperatively on the 3-Tesla MRI scans in a patient with severe end stage OA awaiting total knee replacement surgery. Twelve months after surgery, using a novel metal artefact reduction MRI sequence, we were able to visualize the bone-prosthesis interface and found complete resection and resolution of these BMLs. This is the first reported study in the UK to use this metal artefact reduction MRI sequence at 3-Tesla showing that resection and resolution of BMLs in this patient were associated with an improvement of pain and function after total knee replacement surgery. In this case it was associated with a clinically significant improvement of pain and function after surgery. Failure to eradicate these lesions may be a cause of persistent postoperative pain that is seen in up to 20% of patients following TKR surgery.

  13. Cortical microinfarcts on 3T MRI : Clinical correlates in memory-clinic patients

    NARCIS (Netherlands)

    Van Veluw, Susanne J.; Hilal, Saima; Kuijf, Hugo J.; Ikram, Mohammad Kamran; Xin, Xu; Yeow, Tan Boon; Venketasubramanian, Narayanaswamy; Biessels, Geert Jan; Chen, Christopher

    2015-01-01

    Introduction This is the first study to assess cerebral microinfarcts (CMIs) on 3 tesla (3T) magnetic resonance imaging (MRI) in a memory clinic population. Methods We included 238 consecutive patients (aged 72.5 ± 9.1 years) from a memory clinic in Singapore. All patients underwent extensive neurol

  14. Technical Assessment of Artifact Production from Neuro Endovascular Coil At 3 Tesla MRI: An In Vitro Study

    International Nuclear Information System (INIS)

    Introduction: Magnetic resonance imaging (MRI) is an essential part of the diagnostic procedures in radiology. MRI 3 Tesla becomes more widespread due to high signal to noise ratio (SNR). The use of the neuro endovascular coil to overcome the neuro aneurysm can introduce the artifact in magnetic resonance imaging. Susceptibility artifacts and geometric distortions caused by magnetic field inhomogeneity- related signal loss is used to refer to an artifact in magnetic resonance images. It consists of a region of signal void with a surrounding area of an increased signal intensity that appears to be considerably larger than the actual size of the device causing the artifact. The objective of the study is to compare the size of the artifact on the MR image to the actual size of endovascular coils using a 3 Tesla magnetic resonance imaging system, in vitro study. Methods: The endovascular coils were made from detachable platinum and aneurysm models were constructed by using silicone tube. MRI 3 Tesla Philips Model Achieva with pulse sequence selections were: spin echo, fast spin echo, inversion recovery, fast gradient echo while additional parameters were echo time and turbo factor. Results: Improved visualization of perianeurysmal soft tissues is best accomplished by spin echo for fast spin echo sequences, even better suited to reduce metal artifact. Furthermore, shorter turbo factor and shorter effective TE in the latter sequences are beneficial for the same reason as sequences having shorter TE. Sequences with a shorter TE are preferred because of less time for dephasing and frequency shifting. Imaging at gradient echo series increases susceptibility artifacts. In this in vitro study, some of the major characteristics related to MRI imaging of coil packs have been defined. Discussion: Pulse sequence spin echo is the best sequence reducing the susceptibility artifact. Reducing the TE is the main factor in improving endovascular coil visualization on MRI images. The

  15. Variations of the posterior cerebral artery diagnosed by MR angiography at 3 tesla

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    Uchino, Akira; Saito, Naoko; Takahashi, Masahiro; Okano, Nanami; Tanisaka, Megumi [Saitama Medical University International Medical Center, Department of Diagnostic Radiology, Hidaka, Saitama (Japan)

    2016-02-15

    Fenestration, early bifurcation, and duplication of the posterior cerebral artery (PCA) and the so-called hyperplastic anterior choroidal artery (AChA), considered a variation of the PCA, are rare. We evaluated the prevalence and characteristic features of these PCA variations on magnetic resonance (MR) angiography. We reviewed intracranial MR angiographic images of 2402 patients examined using a 3-tesla scanner. Images from the skull base to the intracranial region were obtained using the standard time-of-flight technique. We excluded images of 52 patients with insufficient image quality or occlusion of the PCA(s) and retrospectively evaluated the images of 2350 patients using a picture archiving and communication system. We observed PCA fenestration in eight (0.34 %) patients, most at the P1 segment and P1-P2 junction and all small in size, early bifurcation at the P1-P2 junction or proximal P2A segment in eight (0.34 %) patients, complete duplication in one patient, and hyperplastic AChA in 13 (0.55 %) patients. Eleven of the 13 hyperplastic AChAs supplied only the territory of the temporal branch of the PCA, and the remaining two supplied the entire territory of the PCA. We observed PCA variations in 30 (1.28 %) patients. We believe the name ''hyperplastic AChA'' inaccurately describes variations of the PCA in which the AChA supplies part of or all of the territory of the PCA and propose ''accessory PCA'' to describe an AChA that supplies part of the territory of the PCA or ''replaced PCA'' to describe that vessel that supplies the territory all branches of the PCA. (orig.)

  16. Variations of the posterior cerebral artery diagnosed by MR angiography at 3 tesla

    International Nuclear Information System (INIS)

    Fenestration, early bifurcation, and duplication of the posterior cerebral artery (PCA) and the so-called hyperplastic anterior choroidal artery (AChA), considered a variation of the PCA, are rare. We evaluated the prevalence and characteristic features of these PCA variations on magnetic resonance (MR) angiography. We reviewed intracranial MR angiographic images of 2402 patients examined using a 3-tesla scanner. Images from the skull base to the intracranial region were obtained using the standard time-of-flight technique. We excluded images of 52 patients with insufficient image quality or occlusion of the PCA(s) and retrospectively evaluated the images of 2350 patients using a picture archiving and communication system. We observed PCA fenestration in eight (0.34 %) patients, most at the P1 segment and P1-P2 junction and all small in size, early bifurcation at the P1-P2 junction or proximal P2A segment in eight (0.34 %) patients, complete duplication in one patient, and hyperplastic AChA in 13 (0.55 %) patients. Eleven of the 13 hyperplastic AChAs supplied only the territory of the temporal branch of the PCA, and the remaining two supplied the entire territory of the PCA. We observed PCA variations in 30 (1.28 %) patients. We believe the name ''hyperplastic AChA'' inaccurately describes variations of the PCA in which the AChA supplies part of or all of the territory of the PCA and propose ''accessory PCA'' to describe an AChA that supplies part of the territory of the PCA or ''replaced PCA'' to describe that vessel that supplies the territory all branches of the PCA. (orig.)

  17. HR 3 tesla MRI for the diagnosis of endolymphatic hydrops and differential diagnosis of inner ear tumors. Demonstrated by two cases with similar symptoms

    International Nuclear Information System (INIS)

    The synchronous appearance of different inner ear pathologies with a nearly equivalent clinical manifestation such as Meniere's disease and vestibular schwannoma is very rare but leads to a relevant dilemma concerning therapy options. MRI is the method of choice to detect intralabyrinthine tumors. Since endolymphatic hydrops is considered the morphological equivalent of Meniere's disease, magnetic resonance imaging including hT2w-FLAIR sequences 4 h after i.v. administration of gadolinium-based contrast agents (GBCA) allows the diagnosis and grading of endolymphatic hydrops in vivo synchronous to diagnosis and monitoring of ILT. To this day, only a few cases of intralabyrinthine schwannoma could be shown to appear simultaneously with endolymphatic hydrops by MRI, but to our knowledge the dedicated distinction of endolymphatic space has not been previously demonstrated. The aim of this work was not only to detect the coincidence of endolymphatic hydrops and vestibular schwannoma, but also to differentiate tumor tissue from endolymphatic space by 3 Tesla MRI. This enables therapy options that are originally indicated for Meniere's disease. The aim of this work was to describe the feasibility and usefulness of endolymphatic hydrops MRI on intralabyrinthal tumors in a special case of intravestibular schwannoma to demonstrate the high clinical relevance and impact in therapeutic decision-making for the synchronous appearance of endolymphatic hydrops and intralabyrinthine tumors. Therefore, we present a typical case of Meniere's disease in contrast to a patient with an intralabyrinthine schwannoma and Meniere's-like symptoms. (orig.)

  18. Orbitofrontal lobe volume deficits in Antipsychotic-Naive schizophrenia: A 3-Tesla MRI study

    Directory of Open Access Journals (Sweden)

    Behere Rishikesh

    2009-01-01

    Full Text Available Background: Prefrontal cortex deficits have been consistently demonstrated in schizophrenia. The orbitofrontal lobe (OFL, a critical component of the prefrontal cortex, subserves social and neuro-cognitive functions. While these functional impairments are established in schizophrenia, the OFL volume deficits have not been well studied, especially in antipsychotic-naοve patients. Aim: To study OFL volume deficits in antipsychotic-naοve schizophrenia patients in comparison with matched healthy controls using high-resolution 3-tesla (3T magnetic resonance imaging (MRI. Materials and Methods: Fourteen antipsychotic-naοve schizophrenia patients (DSM-IV and 14 age-, sex-, handedness- and education-matched healthy controls were scanned using 3T MRI. Psychopathology was assessed in the patient group using the scale for assessment of negative symptoms and the scale for assessment of positive symptoms (SAPS. The OFL volume was measured using Region of Interest (ROI-based manual morphometry technique, with good inter-rater reliability (intra-class correlation coefficient = 0.98. Results: Total OFL volume was significantly smaller in schizophrenia patients (43.3 ± 9.6 mL in comparison with healthy controls (52.1 ± 12.2 mL after controlling for the potential confounding effects of age, sex and intracranial volume (F = 5.3, P = .03. Duration of untreated psychosis did not correlate significantly with OFL volumes. There was a trend towards significant negative correlation between the left and total OFL volumes and SAPS scores (r = -0.49, P = .06. Conclusion: OFL volume deficits might underlie the pathogenesis of schizophrenia symptoms with possible neuro-developmental origins.

  19. MRI at 3 Tesla detects no evidence for ischemic brain damage in intensively treated patients with homozygous familial hypercholesterolemia

    International Nuclear Information System (INIS)

    Homozygous familial hypercholesterolemia (FH) is considered a model disease for excessive plasma cholesterol levels. Patients with untreated homozygous FH have a markedly increased risk for premature atherosclerosis. The frequency and extent of ischemic brain damage detectable by high-field magnetic resonance imaging (MRI) after long-term intensive treatment are unknown. In a case control study, five patients with homozygous FH (one male and four females; mean age: 23.6 ± 9.2, range: 12-36 years; mean pre-treatment serum total cholesterol level: 26.9 ± 3.24 mmol/L; all patients with documented atherosclerotic plaques in the carotid arteries) and five age- and sex-matched healthy controls were studied. All patients had been on maximal lipid-lowering medication since early childhood, and four of them were also on treatment with low-density lipoprotein (LDL) apheresis at bi-weekly intervals. Brain MRI was performed at 3 Tesla field strength with fluid-attenuated T2-weighted inversion recovery and T1-weighted spin-echo MR pulse sequences and subsequently evaluated by two independent readers. The maximal lipid-lowering treatment reduced the total serum cholesterol by more than 50% in the patients, but their serum concentrations were still 3.6-fold higher than those found in the controls (11.9 ± 4.2 vs. 4.5 ± 0.5 mmol/L; p < 0.0047). No brain abnormality was observed in any of the patients with homozygous FH. Homozygous FH patients on intensive cholesterol-lowering therapy have no evidence of ischemic brain damage at 3 Tesla MRI despite the remaining high cholesterol levels. (orig.)

  20. MRI at 3 Tesla detects no evidence for ischemic brain damage in intensively treated patients with homozygous familial hypercholesterolemia

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, Stephan A.; O' Regan, Declan P.; Fitzpatrick, Julie; Hajnal, Joseph V. [Hammersmith Hospital Campus, Imaging Sciences Department, MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College, London (United Kingdom); Neuwirth, Clare; Potter, Elizabeth; Tosi, Isabella; Naoumova, Rossi P. [MRC Clinical Sciences Centre, Clinical Research Facility, London (United Kingdom); Hammersmith Hospital, Lipid Clinic, London (United Kingdom)

    2007-11-15

    Homozygous familial hypercholesterolemia (FH) is considered a model disease for excessive plasma cholesterol levels. Patients with untreated homozygous FH have a markedly increased risk for premature atherosclerosis. The frequency and extent of ischemic brain damage detectable by high-field magnetic resonance imaging (MRI) after long-term intensive treatment are unknown. In a case control study, five patients with homozygous FH (one male and four females; mean age: 23.6 {+-} 9.2, range: 12-36 years; mean pre-treatment serum total cholesterol level: 26.9 {+-} 3.24 mmol/L; all patients with documented atherosclerotic plaques in the carotid arteries) and five age- and sex-matched healthy controls were studied. All patients had been on maximal lipid-lowering medication since early childhood, and four of them were also on treatment with low-density lipoprotein (LDL) apheresis at bi-weekly intervals. Brain MRI was performed at 3 Tesla field strength with fluid-attenuated T2-weighted inversion recovery and T1-weighted spin-echo MR pulse sequences and subsequently evaluated by two independent readers. The maximal lipid-lowering treatment reduced the total serum cholesterol by more than 50% in the patients, but their serum concentrations were still 3.6-fold higher than those found in the controls (11.9 {+-} 4.2 vs. 4.5 {+-} 0.5 mmol/L; p < 0.0047). No brain abnormality was observed in any of the patients with homozygous FH. Homozygous FH patients on intensive cholesterol-lowering therapy have no evidence of ischemic brain damage at 3 Tesla MRI despite the remaining high cholesterol levels. (orig.)

  1. Diagnosis of rotator cuff tears using 3-Tesla MRI versus 3-Tesla MRA: a systematic review and meta-analysis

    International Nuclear Information System (INIS)

    To compare the diagnostic accuracy of magnetic resonance imaging (MRI), 2-dimensional magnetic resonance arthrogram (MRA) and 3-dimensional isotropic MRA in the diagnosis of rotator cuff tears when performed exclusively at 3-T. A systematic review was undertaken of the Cochrane, MEDLINE and PubMed databases in accordance with the PRISMA guidelines. Studies comparing 3-T MRI or 3-T MRA (index tests) to arthroscopic surgical findings (reference test) were included. Methodological appraisal was performed using QUADAS 2. Pooled sensitivity and specificity were calculated and summary receiver-operating curves generated. Kappa coefficients quantified inter-observer reliability. Fourteen studies comprising 1332 patients were identified for inclusion. Twelve studies were retrospective and there were concerns regarding index test bias and applicability in nine and six studies respectively. Reference test bias was a concern in all studies. Both 3-T MRI and 3-T MRA showed similar excellent diagnostic accuracy for full-thickness supraspinatus tears. Concerning partial-thickness supraspinatus tears, 3-T 2D MRA was significantly more sensitive (86.6 vs. 80.5 %, p = 0.014) but significantly less specific (95.2 vs. 100 %, p < 0.001). There was a trend towards greater accuracy in the diagnosis of subscapularis tears with 3-T MRA. Three-Tesla 3D isotropic MRA showed similar accuracy to 3-T conventional 2D MRA. Three-Tesla MRI appeared equivalent to 3-T MRA in the diagnosis of full- and partial-thickness tears, although there was a trend towards greater accuracy in the diagnosis of subscapularis tears with 3-T MRA. Three-Tesla 3D isotropic MRA appears equivalent to 3-T 2D MRA for all types of tears. (orig.)

  2. Diagnosis of rotator cuff tears using 3-Tesla MRI versus 3-Tesla MRA: a systematic review and meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    McGarvey, Ciaran; Harb, Ziad; Smith, Christian; Ajuied, Adil [Guy' s and St Thomas' Hospital, King' s Health Partners, Department of Trauma and Orthopaedics, London (United Kingdom); Houghton, Russell [Guy' s and St Thomas' Hospital, King' s Health Partners, Department of Radiology, London (United Kingdom); Corbett, Steven [Guy' s and St Thomas' Hospital, King' s Health Partners, Department of Trauma and Orthopaedics, London (United Kingdom); Fortius Clinic, London (United Kingdom)

    2016-02-15

    To compare the diagnostic accuracy of magnetic resonance imaging (MRI), 2-dimensional magnetic resonance arthrogram (MRA) and 3-dimensional isotropic MRA in the diagnosis of rotator cuff tears when performed exclusively at 3-T. A systematic review was undertaken of the Cochrane, MEDLINE and PubMed databases in accordance with the PRISMA guidelines. Studies comparing 3-T MRI or 3-T MRA (index tests) to arthroscopic surgical findings (reference test) were included. Methodological appraisal was performed using QUADAS 2. Pooled sensitivity and specificity were calculated and summary receiver-operating curves generated. Kappa coefficients quantified inter-observer reliability. Fourteen studies comprising 1332 patients were identified for inclusion. Twelve studies were retrospective and there were concerns regarding index test bias and applicability in nine and six studies respectively. Reference test bias was a concern in all studies. Both 3-T MRI and 3-T MRA showed similar excellent diagnostic accuracy for full-thickness supraspinatus tears. Concerning partial-thickness supraspinatus tears, 3-T 2D MRA was significantly more sensitive (86.6 vs. 80.5 %, p = 0.014) but significantly less specific (95.2 vs. 100 %, p < 0.001). There was a trend towards greater accuracy in the diagnosis of subscapularis tears with 3-T MRA. Three-Tesla 3D isotropic MRA showed similar accuracy to 3-T conventional 2D MRA. Three-Tesla MRI appeared equivalent to 3-T MRA in the diagnosis of full- and partial-thickness tears, although there was a trend towards greater accuracy in the diagnosis of subscapularis tears with 3-T MRA. Three-Tesla 3D isotropic MRA appears equivalent to 3-T 2D MRA for all types of tears. (orig.)

  3. Combined 3 Tesla MRI Biomarkers Improve the Differentiation between Benign vs Malignant Single Ring Enhancing Brain Masses

    Science.gov (United States)

    Salice, Simone; Esposito, Roberto; Ciavardelli, Domenico; delli Pizzi, Stefano; di Bastiano, Rossella; Tartaro, Armando

    2016-01-01

    Purpose To evaluate whether the combination of imaging biomarkers obtained by means of different 3 Tesla (3T) Magnetic Resonance Imaging (MRI) advanced techniques can improve the diagnostic accuracy in the differentiation between benign and malignant single ring-enhancing brain masses. Materials and Methods 14 patients presenting at conventional 3T MRI single brain mass with similar appearance as regard ring enhancement, presence of peri-lesional edema and absence of hemorrhage signs were included in the study. All lesions were histologically proven: 5 pyogenic abscesses, 6 glioblastomas, and 3 metastases. MRI was performed at 3 Tesla and included Diffusion Weighted Imaging (DWI), Dynamic Susceptibility Contrast -Perfusion Weighted Imaging (DSC-PWI), Magnetic Resonance Spectroscopy (MRS), and Diffusion Tensor Imaging (DTI). Imaging biomarkers derived by those advanced techniques [Cerebral Blood Flow (CBF), relative Cerebral Blood Volume (rCBV), relative Main Transit Time (rMTT), Choline (Cho), Creatine (Cr), Succinate, N-Acetyl Aspartate (NAA), Lactate (Lac), Lipids, relative Apparent Diffusion Coefficient (rADC), and Fractional Anisotropy (FA)] were detected by two experienced neuroradiologists in joint session in 4 areas: Internal Cavity (IC), Ring Enhancement (RE), Peri-Lesional edema (PL), and Contralateral Normal Appearing White Matter (CNAWM). Significant differences between benign (n = 5) and malignant (n = 9) ring enhancing lesions were tested with Mann-Withney U test. The diagnostic accuracy of MRI biomarkers taken alone and MRI biomarkers ratios were tested with Receiver Operating Characteristic (ROC) analysis with an Area Under the Curve (AUC) ≥ 0.9 indicating a very good diagnostic accuracy of the variable. Results Five MRI biomarker ratios achieved excellent accuracy: IC-rADC/PL-NAA (AUC = 1), IC-rADC/IC-FA (AUC = 0.978), RE-rCBV/RE-FA (AUC = 0.933), IC-rADC/RE-FA (AUC = 0.911), and IC-rADC/PL-FA (AUC = 0.911). Only IC-rADC achieved a very good

  4. HR 3 tesla MRI for the diagnosis of endolymphatic hydrops and differential diagnosis of inner ear tumors. Demonstrated by two cases with similar symptoms

    Energy Technology Data Exchange (ETDEWEB)

    Homann, G.; Fahrendorf, D.; Niederstadt, T.; Nagelmann, N.; Heindel, W.; Vieth, V. [University Hospital Muenster (Germany). Dept. of Clinical Radiology; Luetkenhoener, B.; Boeckenfeld, Y.; Basel, T. [University Hospital Muenster (Germany). ENT Clinic

    2014-03-15

    The synchronous appearance of different inner ear pathologies with a nearly equivalent clinical manifestation such as Meniere's disease and vestibular schwannoma is very rare but leads to a relevant dilemma concerning therapy options. MRI is the method of choice to detect intralabyrinthine tumors. Since endolymphatic hydrops is considered the morphological equivalent of Meniere's disease, magnetic resonance imaging including hT2w-FLAIR sequences 4 h after i.v. administration of gadolinium-based contrast agents (GBCA) allows the diagnosis and grading of endolymphatic hydrops in vivo synchronous to diagnosis and monitoring of ILT. To this day, only a few cases of intralabyrinthine schwannoma could be shown to appear simultaneously with endolymphatic hydrops by MRI, but to our knowledge the dedicated distinction of endolymphatic space has not been previously demonstrated. The aim of this work was not only to detect the coincidence of endolymphatic hydrops and vestibular schwannoma, but also to differentiate tumor tissue from endolymphatic space by 3 Tesla MRI. This enables therapy options that are originally indicated for Meniere's disease. The aim of this work was to describe the feasibility and usefulness of endolymphatic hydrops MRI on intralabyrinthal tumors in a special case of intravestibular schwannoma to demonstrate the high clinical relevance and impact in therapeutic decision-making for the synchronous appearance of endolymphatic hydrops and intralabyrinthine tumors. Therefore, we present a typical case of Meniere's disease in contrast to a patient with an intralabyrinthine schwannoma and Meniere's-like symptoms. (orig.)

  5. Non-contrast-enhanced MR angiography at 3 Tesla in patients with advanced peripheral arterial occlusive disease.

    Directory of Open Access Journals (Sweden)

    Kolja M Thierfelder

    Full Text Available PURPOSE: The aim of this study was to assess the diagnostic performance of ECG-gated non-contrast-enhanced quiescent interval single-shot (QISS magnetic resonance angiography at a magnetic field strength of 3 Tesla in patients with advanced peripheral arterial occlusive disease (PAOD. METHOD AND MATERIALS: A total of 21 consecutive patients with advanced PAOD (Fontaine stage IIb and higher referred for peripheral magnetic resonance angiography (MRA were included. Imaging was performed on a 3 T whole body MR. Image quality and stenosis diameter were evaluated in comparison to contrast-enhanced continuous table and TWIST MRA (CE-MRA as standard of reference. QISS images were acquired with a thickness of 1.5 mm each (high-resolution QISS, HR-QISS. Two blinded readers rated the image quality and the degree of stenosis for both HR-QISS and CE-MRA in 26 predefined arterial vessel segments on 5-point Likert scales. RESULTS: With CE-MRA as the reference standard, HR-QISS showed high sensitivity (94.1%, specificity (97.8%, positive (95.1%, and negative predictive value (97.2% for the detection of significant (≥ 50% stenosis. Interreader agreement for stenosis assessment of both HR-QISS and CE-MRA was excellent (κ-values of 0.951 and 0.962, respectively. As compared to CR-MRA, image quality of HR-QISS was significantly lower for the distal aorta, the femoral and iliac arteries (each with p<0.01, while no significant difference was found in the popliteal (p = 0.09 and lower leg arteries (p = 0.78. CONCLUSION: Non-enhanced ECG-gated HR-QISS performs very well in subjects with severe PAOD and is a good alternative for patients with a high risk of nephrogenic systemic fibrosis.

  6. Comparison of whole body MR angiography at 1.5 and 3 Tesla in patients with hereditary hyperlipidemia

    Energy Technology Data Exchange (ETDEWEB)

    Bannas, Peter; Finck-Wedel, Anna Katharina; Buhk, Jan-Hendrik; Bley, Thorsten Alexander; Koops, Andreas; Adam, Gerhard; Weber, Christoph (Dept. of Diagnostic and Interventional Radiology, Univ. Hospital Hamburg-Eppendorf, Hamburg (Germany)), email: p.bannas@uke.uni-hamburg.de; Kooijman, Hendrik (Philips Medical Systems, Hamburg (Germany)); Beil, Frank-Ulrich (Dept. of Internal Medicine, Univ. Hospital Hamburg-Eppendorf, Hamburg (Germany))

    2011-06-15

    Background Patients suffering from hereditary hyperlipidemia have a high risk for premature cardiovascular disease and death as a consequence of accelerated atherosclerosis. Purpose To prospectively and intra-individually compare image quality and detectability of stenoses in contrast enhanced whole-body MRA (WBMRA) at 1.5 and 3 Tesla (T) in patients with hereditary hyperlipidemia. Material and Methods Twenty-seven patients with hereditary hyperlipidemia received a 1.5 and 3 T gadopentetate dimeglumine contrast-enhanced WBMRA. Twenty-three defined arterial segments were analyzed regarding depiction of target vessels and image quality according to a 5-point-scale ('not evaluable' to 'excellent'). Wilcoxon matched pair test was performed for comparison. Forty-three defined arterial segments were analyzed for the degree of stenosis (0%, 1-49%, 50-99% and 100%) as well as vessel alterations such as aneurysms. Chi-square test was performed for comparison. Results 1.5 T and 3 T scans yielded WBMRA with diagnostic quality in all patients. In seven of 23 arterial segments (30.4%) image quality was rated significantly higher at 3 T, whereas there was no significant difference in the remaining 16 segments between WBMRA at 1.5 T and 3 T. All relevant stenoses (n = 5), occlusions (n = 6), and aneurysms (n = 3) were evaluated similarly at both field strengths. Conclusion WBMRA can be performed at 1.5 T and 3 T with diagnostic image quality. Image quality was significantly higher at 3 T than at 1.5 T in only 30.4% of the arterial segments. In order to effectively take advantage of the higher field strength, further optimization of sequence parameters and injection protocols for WBMRA at 3 T is necessary

  7. Clinical photoacoustic imaging of cancer

    Science.gov (United States)

    2016-01-01

    Photoacoustic imaging is a hybrid technique that shines laser light on tissue and measures optically induced ultrasound signal. There is growing interest in the clinical community over this new technique and its possible clinical applications. One of the most prominent features of photoacoustic imaging is its ability to characterize tissue, leveraging differences in the optical absorption of underlying tissue components such as hemoglobin, lipids, melanin, collagen and water among many others. In this review, the state-of-the-art photoacoustic imaging techniques and some of the key outcomes pertaining to different cancer applications in the clinic are presented. PMID:27669961

  8. Accuracy of 3-Tesla MR and MR arthrography in diagnosis of meniscal retear in the post-operative knee

    International Nuclear Information System (INIS)

    This study assesses the accuracy of 3-Tesla (3-T) conventional MR imaging, 3-T MR arthrography, and the combined use of conventional MR and MR arthrography in the diagnosis of meniscal retears as compared with arthroscopy. The study also assess whether there are false-negative cases in which injected contrast does not extend into the meniscus despite a meniscal retear being seen on arthroscopy. One hundred consecutive knee MR arthrograms performed on patients with previous knee surgery were reviewed retrospectively. 3-T conventional MR imaging, 3-T MR arthrography, and the combined use of conventional MR and MR arthrography were assessed for meniscal retears as compared with arthroscopy. The criterion used to diagnose a meniscal retear on MR arthrogram was injected contrast tracking into the meniscus. All patients underwent second-look arthroscopy. Seventy-four patients had conventional MR findings consistent with a meniscal retear. In 83 of the 100 patients, intraarticular contrast helped in demonstrating a retear. In ten patients, there were MR findings consistent with a meniscal retear despite intra-articular contrast not tracking into the meniscus. Ninety-four of the 100 patients had meniscal retears on second-look arthroscopy. Three-Tesla conventional MR examination was 78 % sensitive and 75 % specific, MR arthrogram examination was 88 % sensitive and 100 % specific, and the combined use of MR and MR arthrogram imaging was 98 % sensitive and 75 % specific in the diagnosis of a meniscal retear. The combined use of 3-T MR and MR arthrography allows for high sensitivity and specificity in meniscal retear detection. In some patients, intraarticular contrast will not track into a meniscal retear. When MR findings are consistent with a meniscal retear but contrast does not extend into the meniscus, a meniscal retear is likely. (orig.)

  9. Ventricular Assist Device implant (AB 5000) prototype cannula: In vitro assessment of MRI issues at 3-Tesla

    OpenAIRE

    Valencerina Samuel; Shellock Frank G

    2008-01-01

    Abstract Purpose To evaluate MRI issues at 3-Tesla for a ventricular assist device (VAD). Methods The AB5000 Ventricle with a prototype Nitinol wire-reinforced In-Flow Cannula and Out-Flow Cannula attached (Abiomed, Inc., Danvers, MA) was evaluated for magnetic field interactions, heating, and artifacts at 3-Tesla. MRI-related heating was assessed with the device in a gelled-saline-filled, head/torso phantom using a transmit/received RF body coil while performing MRI at a whole body averaged ...

  10. Testing of a 3 tesla superconducting magnet for the AMY detector at TRISTAN

    International Nuclear Information System (INIS)

    A 3 tesla magnet was constructed and installed in an experimental hall at TRISTAN. Cooldown and excitation tests of the magnet were carried out with a dedicated cryogenic system. The coil has a 2.39 m inner diameter and is 1.54 m long with a radial thickness of 0.1 m. The rated current is 5 kA and the stored energy is 40 MJ. The refrigerator and 17-ton magnet cold mass were cooled to 4.4 K in seven days. Then the magnet was energized to the design current of 5 kA and the mechanical stress of the coil supports was measured. The stress on the supports was well below the allowed maximum. Measurements of the discharge characteristics of the magnet confirmed that the magnet was stable and reliable

  11. Recurrent ulnar nerve entrapment at the elbow: Correlation of surgical findings and 3-Tesla magnetic resonance neurography

    OpenAIRE

    Chhabra, Avneesh; Wadhwa, Vibhor; Thakkar, Rashmi S; John A Carrino; Dellon, A. Lee

    2013-01-01

    The authors describe the correlation between 3-Tesla magnetic resonance neurography (MRN) and surgical findings in two patients who underwent multiple previous failed ulnar nerve surgeries. MRN correctly localized the site of the abnormality. Prospectively observed MRN findings of perineural fibrosis, ulnar nerve re-entrapment abnormalities, medial antebrachial cutaneous neuroma and additional median nerve entrapment were confirmed surgically.

  12. Magnetic Resonance Imaging with a Dielectric Lens

    CERN Document Server

    Vazquez, F; Martin, R; Rodriguez, A O

    2009-01-01

    Recently, metamaterials have been introduced to improve the signal-to-noise ratio (SNR) of magnetic resonance images with very promising results. However, the use polymers in the generation of high quality images in magnetic resonance imaging has not been fully been investigated. These investigations explored the use of a dielectric periodical array as a lens to improve the image SNR generated with single surface coils. Commercial polycarbonate glazing sheets were used together with a circular coil to generate phantom images at 3 Tesla on a clinical MR imager.

  13. Chemical shift imaging at 3 Tesla: effect of echo time on assessing bone marrow abnormalities

    International Nuclear Information System (INIS)

    Our purpose is to test the effect of varied in-phase (IP) and opposed-phase (OP) sequence order on characterizing marrow signal changes at 3T. The study was HIPAA compliant and IRB approved. Informed consent was waived. At 3T, IP and OP sequences were acquired in three patients with biopsy-proven osteosarcomas, using two methods: approach 1 (OP acquisition before IP acquisition) and approach 2 (OP after IP). Signal intensity (SI) measurements in 12 locations of biopsy-proven osteosarcoma and in six locations with normal bone marrow were performed independently by two experienced musculoskeletal radiologists. The signal intensity ratio (SIR) was measured within the marrow where there was T1 signal lower than skeletal muscle. A SIR = 20 % was considered negative. Interobserver agreement was measured by the Lin concordance correlation coefficient (CCC). In 75 % (18/24) of locations within the biopsy-proven tumors, the SIR was >20 % (SI drop more than 20 % in OP compared to IP) using approach 2 and in 100 % (24/24) of the locations the SIR was <20 % (SI drop less than 20 % in OP compared to IP) using approach 1, indicating a high percentage of false-negative results by approach 2, and no false-negative results with approach 1. There was good agreement between observer measurement (CCC = 0.96). At 3T, the OP sequence should be acquired prior to the IP sequence, because susceptibility artifacts on a later-acquired OP sequence may lead to an erroneous interpretation of marrow signal abnormalities. (orig.)

  14. 3 Tesla multiparametric MRI for GTV-definition of Dominant Intraprostatic Lesions in patients with Prostate Cancer – an interobserver variability study

    International Nuclear Information System (INIS)

    To evaluate the interobserver variability of gross tumor volume (GTV) - delineation of Dominant Intraprostatic Lesions (DIPL) in patients with prostate cancer using published MRI criteria for multiparametric MRI at 3 Tesla by 6 different observers. 90 GTV-datasets based on 15 multiparametric MRI sequences (T2w, diffusion weighted (DWI) and dynamic contrast enhanced (DCE)) of 5 patients with prostate cancer were generated for GTV-delineation of DIPL by 6 observers. The reference GTV-dataset was contoured by a radiologist with expertise in diagnostic imaging of prostate cancer using MRI. Subsequent GTV-delineation was performed by 5 radiation oncologists who received teaching of MRI-features of primary prostate cancer before starting contouring session. GTV-datasets were contoured using Oncentra Masterplan® and iplan® Net. For purposes of comparison GTV-datasets were imported to the Artiview® platform (Aquilab®), GTV-values and the similarity indices or Kappa indices (KI) were calculated with the postulation that a KI > 0.7 indicates excellent, a KI > 0.6 to < 0.7 substantial and KI > 0.5 to < 0.6 moderate agreement. Additionally all observers rated difficulties of contouring for each MRI-sequence using a 3 point rating scale (1 = easy to delineate, 2 = minor difficulties, 3 = major difficulties). GTV contouring using T2w (KI-T2w = 0.61) and DCE images (KI-DCE = 0.63) resulted in substantial agreement. GTV contouring using DWI images resulted in moderate agreement (KI-DWI = 0.51). KI-T2w and KI-DCE was significantly higher than KI-DWI (p = 0.01 and p = 0.003). Degree of difficulty in contouring GTV was significantly lower using T2w and DCE compared to DWI-sequences (both p < 0.0001). Analysis of delineation differences revealed inadequate comparison of functional (DWI, DCE) to anatomical sequences (T2w) and lack of awareness of non-specific imaging findings as a source of erroneous delineation. Using T2w and DCE sequences at 3 Tesla for GTV-definition of DIPL in

  15. Assessment of MRI issues at 3-Tesla for metallic surgical implants: findings applied to 61 additional skin closure staples and vessel ligation clips

    OpenAIRE

    Gill Amreeta; Shellock Frank G

    2012-01-01

    Abstract Purpose Metallic skin closure staples and vessel ligation clips should be tested at 3-Tesla to characterize MRI issues in order to ensure patient safety. Therefore, metallic surgical implants were assessed at 3-Tesla for magnetic field interactions, MRI-related heating, and artifacts. Methods A skin closure staple (Visistat Skin Stapler, staple, Polytetrafluoroethylene, PTFE, coated 316L/316LVM stainless steel; Teleflex Medical, Durham, NC) and a vessel ligation clip (Hemoclip Tradit...

  16. Customization of normal data base specific for 3-tesla MRI is mandatory in VSRAD analysis.

    Science.gov (United States)

    Goto, Masami; Suzuki, Yuuichi; Abe, Osamu; Hayashi, Naoto; Aoki, Shigeki; Mori, Harushi; Masumoto, Tomohiko; Watanabe, Yasushi; Satake, Yoshirou; Ino, Kenji; Yano, Keiichi; Iida, Kyouhito; Mima, Kazuo; Ohtomo, Kuni

    2008-07-01

    A voxel-based specific regional analysis system for Alzheimer's disease (VSRAD) was used for quantitative analysis of parahippocampal atropy with 1.5-tesla (T) MRI in a voxel-wise manner. The analysis of images acquired under a different imaging condition provides an error factor that has a calculated value. Clinical application of 3T-MRI is necessary for establishing a normal data base (N-DB) specific for 3T-MRI data, which permits appropriate application of VSRAD. We established an N-DB specific for 3T-MRI for use in VSRAD. The "Z-score of the parahippocampal gyrus" was 0.79 +/- 0.32, and the N-DB of each age group did not have a big deflection when we analyzed a group of physically unimpaired persons in an N-DB specific for 3T-MRI. Therefore, we were able to confirm the validity of the customized N-DB. The "Z-score of the parahippocampal gyrus" was 1.62 +/- 0.47 for the N-DB of VSRAD. The numerical value was high for the group of physically unimpaired persons.

  17. Quantitative assessment of right ventricular function and pulmonary regurgitation in surgically repaired tetralogy of Fallot using 256-slice CT: comparison with 3-Tesla MRI

    Energy Technology Data Exchange (ETDEWEB)

    Yamasaki, Yuzo; Yonezawa, Masato; Matsuo, Yoshio; Kamitani, Takeshi; Higuchi, Ko; Honda, Hiroshi [Graduate School of Medical Sciences, Kyushu University, Department of Clinical Radiology, Higashi-ku, Fukuoka (Japan); Nagao, Michinobu; Kawanami, Satoshi [Graduate School of Medical Sciences, Kyushu University, Department of Molecular Imaging and Diagnosis, Higashi-ku, Fukuoka (Japan); Yamamura, Kenichiro [Graduate School of Medical Sciences, Kyushu University, Department of Pediatrics, Higashi-ku, Fukuoka (Japan); Sakamoto, Ichiro [Graduate School of Medical Sciences, Kyushu University, Department of Cardiovascular Medicine, Higashi-ku, Fukuoka (Japan); Shiokawa, Yuichi [Graduate School of Medical Sciences, Kyushu University, Department of Cardiovascular Surgery, Higashi-ku, Fukuoka (Japan); Yabuuchi, Hidetake [Graduate School of Medical Sciences, Kyushu University, Department of Health Sciences, Higashi-ku, Fukuoka (Japan)

    2014-12-15

    To compare 256-slice cardiac computed tomography (CCT) with cardiac magnetic resonance (CMR) imaging to assess right ventricular (RV) function and pulmonary regurgitant fraction (PRF) in patients with repaired tetralogy of Fallot (TOF). Thirty-three consecutive patients with repaired TOF underwent retrospective ECG-gated CCT and 3-Tesla CMR. RV and left ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF) were measured using CCT and CMR. PRF-CCT (%) was defined as (RVSV - LVSV)/RVSV. PRF-CMR (%) was measured by the phase-contrast method. Repeated measurements were performed to determine intra- and interobserver variability. CCT measurements, including PRF, correlated highly with the CMR reference (r = 0.71-0.96). CCT overestimated RVEDV (mean difference, 17.1 ± 2.9 ml), RVESV (12.9 ± 2.1 ml) and RVSV (4.2 ± 2.0 ml), and underestimated RVEF (-2.6 ± 1.0 %) and PRF (-9.1 ± 2.0 %) compared with CMR. The limits of agreement between CCT and CMR were in a good range for all measurements. The variability in CCT measurements was lower than those in CMR. The estimated effective radiation dose was 7.6 ± 2.6 mSv. 256-slice CCT can assess RV function and PRF with relatively low dose radiation exposure in patients with repaired TOF, but overestimates RV volume and underestimates PRF. (orig.)

  18. Quantitative assessment of right ventricular function and pulmonary regurgitation in surgically repaired tetralogy of Fallot using 256-slice CT: comparison with 3-Tesla MRI

    International Nuclear Information System (INIS)

    To compare 256-slice cardiac computed tomography (CCT) with cardiac magnetic resonance (CMR) imaging to assess right ventricular (RV) function and pulmonary regurgitant fraction (PRF) in patients with repaired tetralogy of Fallot (TOF). Thirty-three consecutive patients with repaired TOF underwent retrospective ECG-gated CCT and 3-Tesla CMR. RV and left ventricular (LV) end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF) were measured using CCT and CMR. PRF-CCT (%) was defined as (RVSV - LVSV)/RVSV. PRF-CMR (%) was measured by the phase-contrast method. Repeated measurements were performed to determine intra- and interobserver variability. CCT measurements, including PRF, correlated highly with the CMR reference (r = 0.71-0.96). CCT overestimated RVEDV (mean difference, 17.1 ± 2.9 ml), RVESV (12.9 ± 2.1 ml) and RVSV (4.2 ± 2.0 ml), and underestimated RVEF (-2.6 ± 1.0 %) and PRF (-9.1 ± 2.0 %) compared with CMR. The limits of agreement between CCT and CMR were in a good range for all measurements. The variability in CCT measurements was lower than those in CMR. The estimated effective radiation dose was 7.6 ± 2.6 mSv. 256-slice CCT can assess RV function and PRF with relatively low dose radiation exposure in patients with repaired TOF, but overestimates RV volume and underestimates PRF. (orig.)

  19. Schnelle zweidimensionale Kartierung der longitudinalen Relaxationszeit T1 bei 1.5 Tesla, 3 Tesla und 7 Tesla mittels Magnetresonanztomographie

    OpenAIRE

    Dieringer, Matthias

    2014-01-01

    Magnetic resonance imaging (MRI) is a non-invasive imaging technique free of ionizing radiation that allows medical imaging of the human body in any arbitrary orientation. Visual but subjective evaluations of longitudinal relaxation time (T1) or transversal relaxation time (T2) weighted images are commonly used in clinical diagnostics of cardiac MRI. For this non-quantitative measure, diagnostic quality depends on external influencing factors such as hardware configuration, sequence parameter...

  20. Ultrasound molecular imaging: Moving toward clinical translation

    Energy Technology Data Exchange (ETDEWEB)

    Abou-Elkacem, Lotfi; Bachawal, Sunitha V.; Willmann, Jürgen K., E-mail: willmann@stanford.edu

    2015-09-15

    Highlights: • Ultrasound molecular imaging is a highly sensitive modality. • A clinical grade ultrasound contrast agent has entered first in human clinical trials. • Several new potential future clinical applications of ultrasound molecular imaging are being explored. - Abstract: Ultrasound is a widely available, cost-effective, real-time, non-invasive and safe imaging modality widely used in the clinic for anatomical and functional imaging. With the introduction of novel molecularly-targeted ultrasound contrast agents, another dimension of ultrasound has become a reality: diagnosing and monitoring pathological processes at the molecular level. Most commonly used ultrasound molecular imaging contrast agents are micron sized, gas-containing microbubbles functionalized to recognize and attach to molecules expressed on inflamed or angiogenic vascular endothelial cells. There are several potential clinical applications currently being explored including earlier detection, molecular profiling, and monitoring of cancer, as well as visualization of ischemic memory in transient myocardial ischemia, monitoring of disease activity in inflammatory bowel disease, and assessment of arteriosclerosis. Recently, a first clinical grade ultrasound contrast agent (BR55), targeted at a molecule expressed in neoangiogenesis (vascular endothelial growth factor receptor type 2; VEGFR2) has been introduced and safety and feasibility of VEGFR2-targeted ultrasound imaging is being explored in first inhuman clinical trials in various cancer types. This review describes the design of ultrasound molecular imaging contrast agents, imaging techniques, and potential future clinical applications of ultrasound molecular imaging.

  1. Role of 3T multiparametric magnetic resonance imaging without endorectal coil in the detection of local recurrent prostate cancer after radical prostatectomy: the radiation oncology point of view

    OpenAIRE

    Couñago, Felipe; Cerro, Elia del; Díaz, Ana Aurora; Marcos, Francisco José; Cerezo, Laura; Maldonado, Antonio; Thuissard Vasallo, Israel John; Rodríguez Martín, José Luis

    2015-01-01

    The aims of this study were to evaluate the role of 3 tesla multiparametric magnetic resonance imaging (3TmMRI) without endorectal coil in the detection of radiographic local recurrences (rLRs) in a contemporary cohort of patients with prostate cancer who presented with biochemical recurrence after radical prostatectomy (RP) with low prostate-specific antigen (PSA) levels, and to identify clinical parameters associated with the 3TmMRI findings.

  2. PET imaging clinical trials: standards for good image quality

    International Nuclear Information System (INIS)

    Full text: Imaging holds a promising place in the drug development process and clinical trials. In recent times, scientists and researchers have realized that imaging enables them to look for new surrogate endpoints and accelerate the process of drug development. As the number of such trials is increasing every year, there is a growing awareness for the need of quality in imaging trials, so as to avoid imaging issues, reduce losses due to non-evaluable imaging and improve subject safety. This paper is an attempt to address the need of standards for good quality image in clinical trials which use imaging. The main focus of the paper is to describe the various acquisition options in PET-CT available for medical imaging, their applicability in drug development process and clinical trials, emphasize the need to identify possible sources that could possibly impact the quality of images, ways of standardizing the equipments and minimizing the variability of different scanners. Additionally this paper will look into the importance of an expert medical imaging group, imaging protocols, quality assurance programs, and image assessment post acquisition for technical compliance and image quality. A reference of standards as prescribed by various scientific bodies and organizations will also be reviewed. In this paper the focus will be mainly to discuss aspects of PET-CT imaging in clinical trials. PET-CT has the potential to be best for response monitoring to therapy and early detection of disease compared to all other imaging modalities such as CT, MRI, gamma camera, SPECT, ultrasonography etc. In research, PET imaging can help in understanding the pharmacokinetics of a molecule, i.e. kinetic modeling and provides various imaging options, qualitative and quantitative. PET-CT provides anatomical as well as functional information and has the potential to be highly reproducible. The paper emphasizes good imaging practices and its relevance, especially when we are not just

  3. Acute inversion injury of the ankle without radiological abnormalities: assessment with high-field MR imaging and correlation of findings with clinical outcome

    International Nuclear Information System (INIS)

    Acute inversion injuries of the ankle are the most common sports accidents, accounting for approximately 10% of emergency room admissions. In up to 85%, an injury of the lateral collateral ligaments is observed. Classically, the assessment of these injuries has relied on clinical examination and radiographs, including stress views. The aim of our study was to correlate prospectively the findings of high-field 3 T MRI in acute ankle distortion with clinical outcome. During a 6-month period, 38 patients were prospectively included. MRI was performed within 48 h of trauma and clinical examination using a protocol consisting of axial T2-weighted and coronal and sagittal T1-weighted images and a sagittal proton density (PDw) sequence. Each ligament injury was graded on a three-point scale. Functional outcome was evaluated using the AOFAS ankle-hindfoot scale. In 24/38 patients (63.12%), ligament injury was observed. In 22/24 cases, this was an injury of the lateral ligaments and in 2/24 cases of the medial ligaments. Injury of the syndesmosis occurred in three patients, a bone bruise in four, and an osteochondral lesion in three cases. Patients with an injury of two or more ligaments or a bone bruise had a lower AOFAS score and returned to sports activities and full weight-bearing later (P < 0.01). MR imaging at 3 Tesla is an independent predictor for clinical outcome. Therefore MRI may be beneficial in those cases where the findings influence further treatment. (orig.)

  4. Acute inversion injury of the ankle without radiological abnormalities: assessment with high-field MR imaging and correlation of findings with clinical outcome

    Energy Technology Data Exchange (ETDEWEB)

    Langner, Inga; Frank, Matthias; Hinz, Peter; Ekkernkamp, Axel [Ernst-Moritz-Arndt-University Greifswald, Department of Trauma and Orthopedic Surgery, Emergency Department, Greifswald (Germany); Kuehn, Jens Peter; Hosten, Norbert; Langner, Soenke [Ernst-Moritz-Arndt-University Greifswald, Institute for Diagnostic Radiology and Neuroradiology, Greifswald (Germany)

    2011-04-15

    Acute inversion injuries of the ankle are the most common sports accidents, accounting for approximately 10% of emergency room admissions. In up to 85%, an injury of the lateral collateral ligaments is observed. Classically, the assessment of these injuries has relied on clinical examination and radiographs, including stress views. The aim of our study was to correlate prospectively the findings of high-field 3 T MRI in acute ankle distortion with clinical outcome. During a 6-month period, 38 patients were prospectively included. MRI was performed within 48 h of trauma and clinical examination using a protocol consisting of axial T2-weighted and coronal and sagittal T1-weighted images and a sagittal proton density (PDw) sequence. Each ligament injury was graded on a three-point scale. Functional outcome was evaluated using the AOFAS ankle-hindfoot scale. In 24/38 patients (63.12%), ligament injury was observed. In 22/24 cases, this was an injury of the lateral ligaments and in 2/24 cases of the medial ligaments. Injury of the syndesmosis occurred in three patients, a bone bruise in four, and an osteochondral lesion in three cases. Patients with an injury of two or more ligaments or a bone bruise had a lower AOFAS score and returned to sports activities and full weight-bearing later (P < 0.01). MR imaging at 3 Tesla is an independent predictor for clinical outcome. Therefore MRI may be beneficial in those cases where the findings influence further treatment. (orig.)

  5. A 128-Channel Receive-Only Cardiac Coil for Highly Accelerated Cardiac MRI at 3 Tesla

    OpenAIRE

    Schmitt, Melanie; Potthast, Andreas; Sosnovik, David E; Polimeni, Jonathan R; Wiggins, Graham C.; Triantafyllou, Christina; Wald, Lawrence L.

    2008-01-01

    A 128-channel receive-only array coil is described and tested for cardiac imaging at 3T. The coil is closely contoured to the body with a “clam-shell” geometry with 68 posterior and 60 anterior elements, each 75 mm in diameter, and arranged in a continuous overlapped array of hexagonal symmetry to minimize nearest neighbor coupling. Signal-to-noise ratio (SNR) and noise amplification for parallel imaging (G-factor) were evaluated in phantom and volunteer experiments. These results were compar...

  6. Clinics in diagnostic imaging. 145.

    Science.gov (United States)

    Bosco, Jerome Irai Ezhil; Low, Albert S C; Tan, Damien M Y; Peh, Wilfred C G

    2013-04-01

    A 63-year-old man presented with painless jaundice, loss of appetite and significant weight loss. Cross-sectional imaging showed a diffusely enlarged pancreas, with no significant fat stranding and a hypodense rim on computed tomography, which appeared hypointense on T2-weighted magnetic resonance imaging. There was a narrowed pancreatic duct and features of common bile duct narrowing in the region of the pancreatic head. However, there was no obvious mass seen in the pancreatic head region. These features were classical of autoimmune pancreatitis with diffuse involvement of the gland. Laboratory investigation showed abnormal liver function and the classical sign of raised immunoglobulin G class 4 antibodies. The patient showed dramatic response to high-dose steroids, with resolution of both the laboratory and imaging abnormalities within one month. We discuss the classical imaging features of Type 1 autoimmune pancreatitis, an uncommon condition that needs to be differentiated from pancreatic malignancy. PMID:23624453

  7. Clinical needs in functional imaging

    Energy Technology Data Exchange (ETDEWEB)

    Atkins, H.L.; Fairchild, R.G.; Richards, P.; Pate, H.

    1979-01-01

    Emission tomography, with positron or single photon emitting radionuclides, offers the possibility of quantitation, a necessary ingredient for functional studies. A figure of merit has been devised as an aid in selecting radionuclides that offer the greatest photon yield for the lowest radiation dose because emission tomography requires a greater information density than conventional imaging. Alterations in function generally precede anatomical alterations and functional imaging may therefore be a more sensitive method of investigating disease processes.

  8. High resolution multimodal clinical ophthalmic imaging system

    OpenAIRE

    Mujat, Mircea; Ferguson, R. Daniel; Patel, Ankit H.; Iftimia, Nicusor; Lue, Niyom; Hammer, Daniel X.

    2010-01-01

    We developed a multimodal adaptive optics (AO) retinal imager which is the first to combine high performance AO-corrected scanning laser ophthalmoscopy (SLO) and swept source Fourier domain optical coherence tomography (SSOCT) imaging modes in a single compact clinical prototype platform. Such systems are becoming ever more essential to vision research and are expected to prove their clinical value for diagnosis of retinal diseases, including glaucoma, diabetic retinopathy (DR), age-related m...

  9. Visual Impairment/lntracranial Pressure Risk Clinical Care Data Tools

    Science.gov (United States)

    Van Baalen, Mary; Mason, Sara S.; Taiym, Wafa; Wear, Mary L.; Moynihan, Shannan; Alexander, David; Hart, Steve; Tarver, William

    2014-01-01

    Prior to 2010, several ISS crewmembers returned from spaceflight with changes to their vision, ranging from a mild hyperopic shift to frank disc edema. As a result, NASA expanded clinical vision testing to include more comprehensive medical imaging, including Optical Coherence Tomography and 3 Tesla Brain and Orbit MRIs. The Space and Clinical Operations (SCO) Division developed a clinical practice guideline that classified individuals based on their symptoms and diagnoses to facilitate clinical care. For the purposes of clinical surveillance, this classification was applied retrospectively to all crewmembers who had sufficient testing for classification. This classification is also a tool that has been leveraged for researchers to identify potential risk factors. In March 2014, driven in part by a more comprehensive understanding of the imaging data and increased imaging capability on orbit, the SCO Division revised their clinical care guidance to outline in-flight care and increase post-flight follow up. The new clinical guidance does not include a classification scheme

  10. 96-Channel Receive-Only Head Coil for 3 Tesla: Design Optimization and Evaluation

    OpenAIRE

    Wiggins, Graham C.; Polimeni, Jonathan R; Potthast, Andreas; Schmitt, Melanie; Alagappan, Vijay; Wald, Lawrence L.

    2009-01-01

    The benefits and challenges of highly parallel array coils for head imaging were investigated through the development of a 3T receive-only phased-array head coil with 96 receive elements constructed on a close-fitting helmet-shaped former. We evaluated several designs for the coil elements and matching circuitry, with particular attention to sources of signal-to-noise ratio (SNR) loss, including various sources of coil loading and coupling between the array elements. The SNR and noise amplifi...

  11. Quantitative Imaging in Cancer Clinical Trials.

    Science.gov (United States)

    Yankeelov, Thomas E; Mankoff, David A; Schwartz, Lawrence H; Lieberman, Frank S; Buatti, John M; Mountz, James M; Erickson, Bradley J; Fennessy, Fiona M M; Huang, Wei; Kalpathy-Cramer, Jayashree; Wahl, Richard L; Linden, Hannah M; Kinahan, Paul E; Zhao, Binsheng; Hylton, Nola M; Gillies, Robert J; Clarke, Laurence; Nordstrom, Robert; Rubin, Daniel L

    2016-01-15

    As anticancer therapies designed to target specific molecular pathways have been developed, it has become critical to develop methods to assess the response induced by such agents. Although traditional, anatomic CT, and MRI examinations are useful in many settings, increasing evidence suggests that these methods cannot answer the fundamental biologic and physiologic questions essential for assessment and, eventually, prediction of treatment response in the clinical trial setting, especially in the critical period soon after treatment is initiated. To optimally apply advances in quantitative imaging methods to trials of targeted cancer therapy, new infrastructure improvements are needed that incorporate these emerging techniques into the settings where they are most likely to have impact. In this review, we first elucidate the needs for therapeutic response assessment in the era of molecularly targeted therapy and describe how quantitative imaging can most effectively provide scientifically and clinically relevant data. We then describe the tools and methods required to apply quantitative imaging and provide concrete examples of work making these advances practically available for routine application in clinical trials. We conclude by proposing strategies to surmount barriers to wider incorporation of these quantitative imaging methods into clinical trials and, eventually, clinical practice. Our goal is to encourage and guide the oncology community to deploy standardized quantitative imaging techniques in clinical trials to further personalize care for cancer patients and to provide a more efficient path for the development of improved targeted therapies.

  12. Clinics in diagnostic imaging (166)

    OpenAIRE

    Goh, Lin Wah; Chinchure, Dinesh; Lim, Tze Chwan

    2016-01-01

    A 68-year-old woman with poorly controlled diabetes mellitus presented to the emergency department with choreoathetoid movements affecting the upper and lower left limbs. Computed tomography of the brain did not show any intracranial abnormalities. However, subsequent magnetic resonance (MR) imaging of the brain revealed an increased T1 signal in the right basal ganglia, raising the suspicion of nonketotic hyperglycaemic chorea-hemiballismus. Management consisted of adjusting her insulin dose...

  13. Hepatic Iron Quantification on 3 Tesla (3 T) Magnetic Resonance (MR): Technical Challenges and Solutions

    International Nuclear Information System (INIS)

    MR has become a reliable and noninvasive method of hepatic iron quantification. Currently, most of the hepatic iron quantification is performed on 1.5 T MR, and the biopsy measurements have been paired with R2 and R2* values for 1.5 T MR. As the use of 3 T MR scanners is steadily increasing in clinical practice, it has become important to evaluate the practicality of calculating iron burden at 3 T MR. Hepatic iron quantification on 3 T MR requires a better understanding of the process and more stringent technical considerations. The purpose of this work is to focus on the technical challenges in establishing a relationship between T2* values at 1.5 T MR and 3 T MR for hepatic iron concentration (HIC) and to develop an appropriately optimized MR protocol for the evaluation of T2* values in the liver at 3 T magnetic field strength. We studied 22 sickle cell patients using multiecho fast gradient-echo sequence (MFGRE) 3 T MR and compared the results with serum ferritin and liver biopsy results. Our study showed that the quantification of hepatic iron on 3 T MRI in sickle cell disease patients correlates well with clinical blood test results and biopsy results. 3 T MR liver iron quantification based on MFGRE can be used for hepatic iron quantification in transfused patients

  14. Robust diffusion imaging framework for clinical studies

    CERN Document Server

    Maximov, Ivan I; Neuner, Irene; Shah, N Jon

    2015-01-01

    Clinical diffusion imaging requires short acquisition times and good image quality to permit its use in various medical applications. In turn, these demands require the development of a robust and efficient post-processing framework in order to guarantee useful and reliable results. However, multiple artefacts abound in in vivo measurements; from either subject such as cardiac pulsation, bulk head motion, respiratory motion and involuntary tics and tremor, or imaging hardware related problems, such as table vibrations, etc. These artefacts can severely degrade the resulting images and render diffusion analysis difficult or impossible. In order to overcome these problems, we developed a robust and efficient framework enabling the use of initially corrupted images from a clinical study. At the heart of this framework is an improved least trimmed squares diffusion tensor estimation algorithm that works well with severely degraded datasets with low signal-to-noise ratio. This approach has been compared with other...

  15. Inferior parietal lobule volume and schneiderian first-rank symptoms in Antipsychotic-Naive schizophrenia: A 3-Tesla MRI study

    Directory of Open Access Journals (Sweden)

    Danivas Vijay

    2009-01-01

    Full Text Available Background: As per Frith′s neuro-cognitive model, inferior parietal lobule (IPL is implicated in the pathogenesis of Schneiderian first-rank symptoms (FRS in schizophrenia. The specific role of IPL structural abnormalities in the pathogenesis of FRS is yet to be ascertained. Materials and Methods: Using 3-tesla MRI scanner, this first-time study examined antipsychotic-naοve schizophrenia patients ( n = 28 (patients with FRS [FRS +]: N = 14, M: F = 7:7; and patients without FRS [FRS-]: N = 14, M: F = 7:7 in comparison with sex-, handedness-, education- and socioeconomic status-matched healthy controls ( n = 14, M: F = 7:7. The volume of IPL was measured using a three-dimensional, interactive, semi-automated analysis, with good inter-rater reliability. Results: FRS + patients showed significant volume deficit in right IPL in comparison with healthy controls (F = 4.0; P=.028 after controlling for the potential confounding effects of age, sex and intracranial volume. Conclusions: Right IPL volume deficit in FRS+patients adds further support to the Frith′s model of FRS in schizophrenia.

  16. Evaluation of Iron Deposition in the Adrenal Glands of β Thalassemia Major Patients Using 3-Tesla MRI

    Directory of Open Access Journals (Sweden)

    Guzelbey

    2016-05-01

    Full Text Available Background Beta-thalassemia major (β-TM patients need blood transfusions, which result in iron deposition. To regulate chelation therapy, iron load has to be measured. With MRI, the amount of signal loss and T2* decay time shortening are used for iron quantification. Objectives The aim was to measure adrenal iron load with T2* relaxometry using MRI, and to compare it with liver and cardiac iron and serum ferritin, and to find out whether adrenal iron could be predicted from those parameters. Patients and Methods Between October 2014 and March 2015, MRI was performed in 21 patients with β-TM, recieving blood transfusions and chelation therapy. The control group (n = 11 included healthy volunteers with no known history of adrenal, hematologic, chronic disease, and blood transfusion. Results Among patients, there was no significant correlation between plasma ferritin and adrenal T2*. Significant difference was detected among T2* values of adrenals between the patient and control groups. There was no significant correlation between adrenal gland and liver T2* in β-TM patients, moderate correlation was detected between adrenal T2* and cardiac T2*. Conclusion Adrenal iron in β-TM can be reliably measured in 3 Tesla MRI. The results highlight the absence of correlation between adrenal iron deposition both with serum ferritin and hepatic iron.

  17. Quantitative imaging for clinical dosimetry

    Science.gov (United States)

    Bardiès, Manuel; Flux, Glenn; Lassmann, Michael; Monsieurs, Myriam; Savolainen, Sauli; Strand, Sven-Erik

    2006-12-01

    Patient-specific dosimetry in nuclear medicine is now a legal requirement in many countries throughout the EU for targeted radionuclide therapy (TRT) applications. In order to achieve that goal, an increased level of accuracy in dosimetry procedures is needed. Current research in nuclear medicine dosimetry should not only aim at developing new methods to assess the delivered radiation absorbed dose at the patient level, but also to ensure that the proposed methods can be put into practice in a sufficient number of institutions. A unified dosimetry methodology is required for making clinical outcome comparisons possible.

  18. In Vivo Quantification of Cerebral R2FNx01-Response to Graded Hyperoxia at 3 Tesla

    Directory of Open Access Journals (Sweden)

    Grigorios Gotzamanis

    2015-01-01

    Full Text Available Objectives: This study aims to quantify the response of the transverse relaxation rate of the magnetic resonance (MR signal of the cerebral tissue in healthy volunteers to the administration of air with step-wise increasing percentage of oxygen. Materials and Methods: The transverse relaxation rate (R2FNx01 of the MR signal was quantified in seven volunteers under respiratory intake of normobaric gas mixtures containing 21, 50, 75, and 100% oxygen, respectively. End-tidal breath composition, arterial blood saturation (SaO 2 , and heart pulse rate were monitored during the challenge. R2FNx01 maps were computed from multi-echo, gradient-echo magnetic resonance imaging (MRI data, acquired at 3.0T. The average values in the segmented white matter (WM and gray matter (GM were tested by the analysis of variance (ANOVA, with Bonferroni post-hoc correction. The GM R2FNx01-reactivity to hyperoxia was modeled using the Hill′s equation. Results: Graded hyperoxia resulted in a progressive and significant (P < 0.05 decrease of the R2FNx01 in GM. Under normoxia the GM-R2FNx01 was 17.2 ± 1.1 s -1 . At 75% O 2 supply, the R2FNx01 had reached a saturation level, with 16.4 ± 0.7 s -1 (P = 0.02, without a significant further decrease for 100% O 2 . The R2FNx01-response of GM correlated positively with CO 2 partial pressure (R = 0.69 ± 0.19 and negatively with SaO 2 (R = -0.74 ± 0.17. The WM showed a similar progressive, but non-significant, decrease in the relaxation rates, with an increase in oxygen intake (P = 0.055. The Hill′s model predicted a maximum R2FNx01 response of the GM, of 3.5%, with half the maximum at 68% oxygen concentration. Conclusions: The GM-R2FNx01 responds to hyperoxia in a concentration-dependent manner, suggesting that monitoring and modeling of the R2FNx01-response may provide new oxygenation biomarkers for tumor therapy or assessment of cerebrovascular reactivity in patients.

  19. Barrett's esophagus: clinical features, obesity, and imaging.

    LENUS (Irish Health Repository)

    Quigley, Eamonn M M

    2011-09-01

    The following includes commentaries on clinical features and imaging of Barrett\\'s esophagus (BE); the clinical factors that influence the development of BE; the influence of body fat distribution and central obesity; the role of adipocytokines and proinflammatory markers in carcinogenesis; the role of body mass index (BMI) in healing of Barrett\\'s epithelium; the role of surgery in prevention of carcinogenesis in BE; the importance of double-contrast esophagography and cross-sectional images of the esophagus; and the value of positron emission tomography\\/computed tomography.

  20. Functional brain imaging - baric and clinical questions

    International Nuclear Information System (INIS)

    The advancing biological knowledge of disease processes plays a central part in the progress of modern psychiatry. An essential contribution comes from the functional and structural brain imaging techniques (CT, MRI, SPECT, PET). Their application is important for biological oriented research in psychiatry and there is also a growing relevance in clinical aspects. This development is taken into account by recent diagnostic classification systems in psychiatry. The capabilities and limitations of functional brain imaging in the context of research and clinic will be presented and discussed by examples and own investigations. (orig.)

  1. Three-Tesla magnetic resonance elastography for hepatic fibrosis: Comparison with diffusion-weighted imaging and gadoxetic acid-enhanced magnetic resonance imaging

    OpenAIRE

    Park, Hee Sun; Kim, Young Jun; Yu, Mi Hye; Choe, Won Hyeok; Jung, Sung Il; Jeon, Hae Jeong

    2014-01-01

    AIM: To evaluate the feasibility of 3-Tesla magnetic resonance elastography (MRE) for hepatic fibrosis and to compare that with diffusion-weighted imaging (DWI) and gadoxetic acid-enhanced magnetic resonance (MR) imaging.

  2. Clinical efficiency, image quality and dosimetric considerations

    International Nuclear Information System (INIS)

    Three decades have passed since the first clinical use of the famous EMI Computed Axial Tomography (Cat) scanner. At the time, the prospects for clinical success of this innovative idea were not very good. Time, however, has proven otherwise as what is now simply known as Computed tomography (CT) has been boosted in each one of these decades for different reasons. In the 1970s, technological progress augmented by the realization of the importance of tomographic imaging got everything started; in the 1980s, the boom in health care demand in the US solidified its position and in the 1990s the technological explosion in computers and the imperative need to lower costs in the health care industry have prompted the most dramatic changes in the wy CT is utilized in the year 2000. Thus, different motivations have led the way of progress in CT at various times, and in spite of amazing developments in other crucial imaging modalities, such as ultrasound, Doppler ultrasound, digital subtraction angiography and magnetic resonance imaging, CT maintains its rightful place as the premiere imaging modality in the modern radiology department. This work covers the basic principles of tomographic image reconstruction, and how axial CT scanners progressed historically in the first two decades. Developments in X-ray tubes, and detection systems are highlighted, as well as the impact of clinical efficiency, image quality and patient doses. The basic construction of translate-rotate (1st and 2nd generation, rotate-rotate (3rd generation) and detector ring (4th generation) scanners are described. The so-called 5th generation scanner, the electron beam scanner, is also described, with its clinical and technical advantages and its inherent financial and maintenance disadvantages, which brought the advent of spiral and multi-slice scanners. These most recent developments in CT technology have opened a new era in the clinical use of CT; and although image quality has reached an expected

  3. MR visualization of the inner ear structures: comparison of 1.5 Tesla and 3 Tesla images

    Energy Technology Data Exchange (ETDEWEB)

    Graf, H.; Schick, F. [Tuebingen Univ. (Germany). Sektion Experimentelle Radiologie; Claussen, C.D.; Seemann, M.D. [Tuebingen Univ. (Germany). Abt. fuer Radiologische Diagnostik

    2004-01-01

    Aim of the Study: To compare high resolution MRI examinations of inner ear structures at 1.5 T and at 3 T. Method: Temporal bones were measured bilaterally in 3 healthy volunteers in a 1.5 T and in a 3 T MR-scanner using the respective one channel head coil (quadrature detection) of the manufacturer. The same steady-state gradient echo sequence (3D-CISS) was employed at a voxel size of 0.4x0.4x0.4mm{sup 3}. The signal-to-noise ratio (SNR) was determined quantitatively. Results: An SNR of 8 could be achieved for the measurements at 3 T in 7:37 min. The SNR at 3 T was, on average, a factor of 1.34 higher than that at 1.5 T despite the fact that the excitation angle had to be drastically reduced ({alpha} = 42 instead of {alpha} = 70 at 1.5 T) due to the limit of the specific absorption rate (SAR). Discussion: The MR representation of the inner ear is clearly improved at 3 T. To obtain the same SNR at 1.5 T approximately the double measuring time would be required, connected with reduced patient comfort and an increased risk for a displacement of the head during the high resolution measurement. (orig.) [German] Ziel der Studie: Vergleich der hochaufloesenden MR-Bildgebung der Innenohrstrukturen bei 1,5 T und 3 T. Methode: Es wurden jeweils beide Felsenbeine von 3 freiwilligen, gehoergesunden Probanden an einem 1,5 T und einem 3 T MR-Tomographen mit einer einkanaligen Quadratur-Kopfspule des Herstellers gemessen. An beiden Tomographen wurde dieselbe Steady-State Gradientenecho-Sequenz (3D-CISS) bei einer Voxelgroesse von 0,4x0,4x0,4mm{sup 3} verwendet. Das erhaltene Signal-Rausch-Verhaeltnis (SNR) wurde quantitativ ermittelt. Ergebnis: Ein SNR von 8 wurde fuer die Messungen bei 3 T in 7:37 min erreicht. Der SNR-Wert bei 3 T uebertraf den Wert bei 1,5 T um durchschnittlich das 1,34-fache, obwohl aufgrund der Begrenzung in der spezifischen Absorptionsrate (SAR) nur mit deutlich reduziertem Anregewinkel ({alpha} = 42 anstatt {alpha} = 70 bei 1,5 T) gearbeitet werden konnte. Diskussion: Die Innenohrdarstellung mittels MRT wird bei 3 T deutlich verbessert. Bei 1,5 T waere fuer dasselbe SNR ungefaehr die doppelte Messzeit erforderlich, verbunden mit deutlich reduziertem Patientenkomfort und einem erhoehten Risiko fuer eine Verlagerung des Kopfes waehrend der hochaufgeloesten Messung. (orig.)

  4. 3 Tesla proton MRI for the diagnosis of pneumonia/lung infiltrates in neutropenic patients with acute myeloid leukemia: Initial results in comparison to HRCT

    International Nuclear Information System (INIS)

    Purpose: To evaluate the diagnostic accuracy of 3 Tesla proton MRI for the assessment of pneumonia/lung infiltrates in neutropenic patients with acute myeloid leukemia. Material and methods: In a prospective study, 3 Tesla MRI was performed in 19 febrile neutropenic patients (5 women, 14 men; mean age 61 years ± 14.2; range 23–77 years). All patients underwent high-resolution CT less than 24 h prior to MRI. The MRI protocol (Magnetom Tim Trio, Siemens) included a T2-weighted HASTE sequence (TE/TR: 49 ms/∞, slice thickness 6 mm) and a high-resolution 3D VIBE sequence with an ultra-short TE < 1 ms (TE/TR 0.8/2.9 ms, slice thickness 2 mm). The VIBE sequence was examined before and after intravenous injection of 0.1 mmol/kg gadoterate meglumine (Dotarem, Guerbet). The presence of pulmonary abnormalities, their location within the lung, and lesion type (nodules, consolidations, glass opacity areas) were analyzed by one reader and compared to the findings of HRCT, which was evaluated by a second independent radiologist who served as the reference standard. The findings were compared per lobe in each patient and rated as true positive (TP) findings if all three characteristics (presence, location, and lesion type) listed above were concordant to HRCT. Results: Pulmonary abnormalities were characterized by 3 Tesla MRI with a sensitivity of 82.3% and a specificity of 78.6%, resulting in an overall accuracy of 88% (NPV/PPV 66.7%/89.5%). In 51 lobes (19 of 19 patients), pulmonary abnormalities visualized by MR were judged to be concordant in their location and in the lesion type identified by both readers. In 22 lobes (11 of 19 patients), no abnormalities were present on either MR or HRCT (true negative). In 6 lobes (5 of 19 patients), ground glass opacity areas were detected on MRI but were not visible on HRCT (false positives). In 11 lobes (7 of 19 patients), MRI failed to detect ground glass opacity areas identified by HRCT. However, since the abnormalities were

  5. 3 Tesla proton MRI for the diagnosis of pneumonia/lung infiltrates in neutropenic patients with acute myeloid leukemia: Initial results in comparison to HRCT

    Energy Technology Data Exchange (ETDEWEB)

    Attenberger, U.I., E-mail: ulrike.attenberger@umm.de [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim (Germany); Morelli, J.N. [Scott and White Hospital, Texas A and M Health Sciences Center, Temple (United States); Henzler, T. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim (Germany); Buchheidt, D. [Department of Hematology and Oncology, University Medical Center Mannheim (Germany); Fink, C. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim (Germany); Department of Radiology, AKH Celle, Celle (Germany); Schoenberg, S.O.; Reichert, M. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim (Germany)

    2014-01-15

    Purpose: To evaluate the diagnostic accuracy of 3 Tesla proton MRI for the assessment of pneumonia/lung infiltrates in neutropenic patients with acute myeloid leukemia. Material and methods: In a prospective study, 3 Tesla MRI was performed in 19 febrile neutropenic patients (5 women, 14 men; mean age 61 years ± 14.2; range 23–77 years). All patients underwent high-resolution CT less than 24 h prior to MRI. The MRI protocol (Magnetom Tim Trio, Siemens) included a T2-weighted HASTE sequence (TE/TR: 49 ms/∞, slice thickness 6 mm) and a high-resolution 3D VIBE sequence with an ultra-short TE < 1 ms (TE/TR 0.8/2.9 ms, slice thickness 2 mm). The VIBE sequence was examined before and after intravenous injection of 0.1 mmol/kg gadoterate meglumine (Dotarem, Guerbet). The presence of pulmonary abnormalities, their location within the lung, and lesion type (nodules, consolidations, glass opacity areas) were analyzed by one reader and compared to the findings of HRCT, which was evaluated by a second independent radiologist who served as the reference standard. The findings were compared per lobe in each patient and rated as true positive (TP) findings if all three characteristics (presence, location, and lesion type) listed above were concordant to HRCT. Results: Pulmonary abnormalities were characterized by 3 Tesla MRI with a sensitivity of 82.3% and a specificity of 78.6%, resulting in an overall accuracy of 88% (NPV/PPV 66.7%/89.5%). In 51 lobes (19 of 19 patients), pulmonary abnormalities visualized by MR were judged to be concordant in their location and in the lesion type identified by both readers. In 22 lobes (11 of 19 patients), no abnormalities were present on either MR or HRCT (true negative). In 6 lobes (5 of 19 patients), ground glass opacity areas were detected on MRI but were not visible on HRCT (false positives). In 11 lobes (7 of 19 patients), MRI failed to detect ground glass opacity areas identified by HRCT. However, since the abnormalities were

  6. Comprehensive small animal imaging strategies on a clinical 3 T dedicated head MR-scanner; adapted methods and sequence protocols in CNS pathologies.

    Directory of Open Access Journals (Sweden)

    Deepu R Pillai

    Full Text Available BACKGROUND: Small animal models of human diseases are an indispensable aspect of pre-clinical research. Being dynamic, most pathologies demand extensive longitudinal monitoring to understand disease mechanisms, drug efficacy and side effects. These considerations often demand the concomitant development of monitoring systems with sufficient temporal and spatial resolution. METHODOLOGY AND RESULTS: This study attempts to configure and optimize a clinical 3 Tesla magnetic resonance scanner to facilitate imaging of small animal central nervous system pathologies. The hardware of the scanner was complemented by a custom-built, 4-channel phased array coil system. Extensive modification of standard sequence protocols was carried out based on tissue relaxometric calculations. Proton density differences between the gray and white matter of the rodent spinal cord along with transverse relaxation due to magnetic susceptibility differences at the cortex and striatum of both rats and mice demonstrated statistically significant differences. The employed parallel imaging reconstruction algorithms had distinct properties dependent on the sequence type and in the presence of the contrast agent. The attempt to morphologically phenotype a normal healthy rat brain in multiple planes delineated a number of anatomical regions, and all the clinically relevant sequels following acute cerebral ischemia could be adequately characterized. Changes in blood-brain-barrier permeability following ischemia-reperfusion were also apparent at a later time. Typical characteristics of intra-cerebral haemorrhage at acute and chronic stages were also visualized up to one month. Two models of rodent spinal cord injury were adequately characterized and closely mimicked the results of histological studies. In the employed rodent animal handling system a mouse model of glioblastoma was also studied with unequivocal results. CONCLUSIONS: The implemented customizations including extensive

  7. Clinical Applications of Diffusion Tensor Imaging

    Directory of Open Access Journals (Sweden)

    Sona Saksena

    2008-01-01

    Full Text Available During the last decade, advances in the field of magnetic resonance imaging (MRI have led to the design of numerous innovative imaging techniques. These techniques have not only facilitated structural visualization of anatomy, but also have provided a wealth of functional information regarding biological processes. Diffusion tensor imaging (DTI is one such MRI technique that has generated tremendous amount of interest both in the clinical and laboratory fields. DTI attempts to analyze the magnitude and orientation of random microscopic motion of water molecules in brain tissue. It is based upon the phenomenon of water diffusion known as Brownian motion. This technique pro- vides details on tissue microstructure and organization well beyond the usual image resolution. With diffusion tensor MR imaging, diffusion anisotropy can be quantified and subtle white matter changes not normally seen on conventional MRI can be detected. These features have encouraged scientists to evaluate the integrity and direction of the fiber tracts in various pathological conditions using DTI. Tissue maladies studied by DTI in this review include cerebral ischemia and wallerian degeneration, epilepsy, multiple sclerosis, Alzheimer’s disease, schizophrenia, metabolic disorders, infections and brain tumors. We have only included the common clinical conditions to keep this review precise.

  8. Intracranial Infections: Clinical and Imaging Characteristics

    International Nuclear Information System (INIS)

    The radiologist plays a crucial role in identifying and narrowing the differential diagnosis of intracranial infections. A thorough understanding of the intracranial compartment anatomy and characteristic imaging findings of specific pathogens, as well incorporation of the clinical information, is essential to establish correct diagnosis. Specific types of infections have certain propensities for different anatomical regions within the brain. In addition, the imaging findings must be placed in the context of the clinical setting, particularly in immunocompromised and human immunodeficiency virus (HIV)-positive patients. This paper describes and depicts infections within the different compartments of the brain. Pathology-proven infectious cases are presented in both immunocompetent and immunocompromised patients, with a discussion of the characteristic findings of each pathogen. Magnetic resonance spectroscopy (MRS) characteristics for several infections are also discussed

  9. Clinical application of several tumor imaging agents

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Neoplasms is one of the main diseases for harming health.It is difficult to prevent the neoplasms because the factors of bringing out them are complex.To raise survival rate the early diagnosis of tumors is very important.Radionuclide imaging is useful to detect recurrent or residual diseaseand to identificate benign or malignant tumor.Several tumorimaging agents as following have clinical significance indiagnosing tumors.

  10. Metanephric Adenoma: clinical, imaging, and histological findings

    Energy Technology Data Exchange (ETDEWEB)

    Torricelli, Fabio Cesar Miranda; Marchini, Giovanni Scala, E-mail: fabio_torri@yahoo.com.b [Universidade de Sao Paulo (USP), SP (Brazil). Faculdade de Medicina. Dept. de Urologica; Campos, Rodrigo Sousa Madeira [Hospital do Servidor Publico Estadual, Sao Paulo, SP (Brazil). Dept. de Urologia; Gil, Antonio Otero [Instituto Dante Pazanezzi, Sao Paulo, SP (Brazil)

    2011-07-01

    Metanephric adenoma (MA), also designated nephrogenic nephroma or renal epithelial tumor resembling immature nephron, has just been recently recognized as a special type of benign renal epithelial tumor. Only few reports are found in the literature regarding this rare renal tumor. The purpose of this paper is to describe our clinical, imaging and histological / immunohistochemical observations of MA diagnosed in two patients and compare these data to previous information reported in medical databases (author)

  11. Metanephric Adenoma: clinical, imaging, and histological findings

    International Nuclear Information System (INIS)

    Metanephric adenoma (MA), also designated nephrogenic nephroma or renal epithelial tumor resembling immature nephron, has just been recently recognized as a special type of benign renal epithelial tumor. Only few reports are found in the literature regarding this rare renal tumor. The purpose of this paper is to describe our clinical, imaging and histological / immunohistochemical observations of MA diagnosed in two patients and compare these data to previous information reported in medical databases (author)

  12. Is the body-coil at 3 Tesla feasible for the MRI evaluation of the painful knee? A comparative study

    International Nuclear Information System (INIS)

    The purpose of this study was to compare the in-built body coil of the 3.0-Tesla (T) scanner with a dedicated surface coil of a 1.5 T system regarding knee imaging. We performed an intraindividual prospective clinical trial on 17 patients with knee pain using magnetic resonance imaging (MRI) at 1.5 and 3.0 T systems equipped with identical gradient systems. Proton-density-weighted turbo spin echo sequences with the same spatial resolution and comparable contrast parameters were used. A quantitative measurement of signal to noise ratio (SNR), relative contrast (RC) and contrast to noise ratio (CNR) between muscle and bone marrow was performed, followed by a qualitative assessment of anatomic/pathologic structures and the extent of artefacts. At 3.0 T, 30 lesions (91%) compared to 33 lesions at 1.5 T were detected. The SNR/CNR/RC were moderately reduced at 3.0 T versus 1.5 T (muscle 42 vs 47 and bone 83 vs 112/46 vs 69/0.33 vs 0.43). Motion artefacts from the pulsating popliteal artery were significantly increased at 3.0 T. A visible and measurable signal loss occurred at 3.0 T using the built-in body coil compared with the dedicated 1.5 T knee coil, but nearly all clinically important information could be obtained. (orig.)

  13. Assessment of MRI issues at 3-Tesla for metallic surgical implants: findings applied to 61 additional skin closure staples and vessel ligation clips

    Directory of Open Access Journals (Sweden)

    Gill Amreeta

    2012-01-01

    Full Text Available Abstract Purpose Metallic skin closure staples and vessel ligation clips should be tested at 3-Tesla to characterize MRI issues in order to ensure patient safety. Therefore, metallic surgical implants were assessed at 3-Tesla for magnetic field interactions, MRI-related heating, and artifacts. Methods A skin closure staple (Visistat Skin Stapler, staple, Polytetrafluoroethylene, PTFE, coated 316L/316LVM stainless steel; Teleflex Medical, Durham, NC and a vessel ligation clip (Hemoclip Traditional, stainless steel; Teleflex Medical, Durham, NC that represented the largest metallic sizes made from materials with the highest magnetic susceptibilities (i.e., based on material information among 61 other surgical implants (52 metallic implants, 9 nonmetallic implants underwent evaluation for magnetic field interactions, MRI-related heating, and artifacts using standardized techniques. MRI-related heating was assessed by placing each implant in a gelled-saline-filled phantom with MRI performed using a transmit/receive RF body coil at an MR system reported, whole body averaged SAR of 2.9-W/kg for 15-min. Artifacts were characterized using T1-weighted, SE and GRE pulse sequences. Results Each surgical implant showed minor magnetic field interactions (20- and 27-degrees, which is acceptable from a safety consideration. Heating was not substantial (highest temperature change, ≤ 1.6°C. Artifacts may create issues if the area of interest is in the same area or close to the respective surgical implant. Conclusions The results demonstrated that it would be acceptable for patients with these metallic surgical implants to undergo MRI at 3-Tesla or less. Because of the materials and dimensions of the surgical implants that underwent testing, these findings pertain to 61 additional similar implants.

  14. Clinical imaging of multidrug resistance in cancer

    Energy Technology Data Exchange (ETDEWEB)

    Del Vecchi, S.; Ciarmiello, A.; Salvatore, M. [Naples Univ. Federico 2. (Italy). Medicina Nucleare. Dipt. di Scienze Biomorfologiche e Funzionali

    1999-06-01

    The most well-characterized mechanism of multidrug resistance (MDR) involves P-glycoprotein (Pgp), a transmembrane protein acting as an ATP-dependent drug efflux pump. The recognition of {sup 9}9mTc-Sestamibi and other lipophilic cations as transport substrates for Pgp provided the necessary tool for the clinical assessment of Pgp function in patients with cancer. Many clinical studies from different institutions and trials including variety of malignancies indicate that both tumor uptake and clearance of {sup 9}9mTc-Sestamibi are correlate with Pgp expression and may be used for the phenotypic assessment of multidrug resistance. Although both parameters may predict tumor responsible to chemotherapy, the extraction of efflux rate constants appeared o provide a more direct index of Pgp function as compared tp tracer uptake ratio allowing to trace a continuous spectrum of drug transport activity. Preliminary studies the use of MDR imaging agents to monitor the modulating ability of revertant compounds. Although the results support the feasibility of this approach, the alteration of tracer pharmacokinetics induced by the modulators certainly constitute a challenge in the development of a simple functional test suitable in clinical practice. The extension of the acquired imaging methodology to tumors with redundant intrinsic resistant mechanism. Due to multifactorial nature of phenomenon, the development of new tracers with substrate specificity for other known the complex array of cellular mechanisms contributing to treatment failure.

  15. Clinical image quality evaluation for panoramic radiography in Korean dental clinics

    OpenAIRE

    Choi, Bo-ram; Choi, Da-Hye; Huh, Kyung-Hoe; Yi, Won-Jin; Heo, Min-Suk; Choi, Soon-Chul; Bae, Kwang-Hak; Lee, Sam-Sun

    2012-01-01

    Purpose The purpose of this study was to investigate the level of clinical image quality of panoramic radiographs and to analyze the parameters that influence the overall image quality. Materials and Methods Korean dental clinics were asked to provide three randomly selected panoramic radiographs. An oral and maxillofacial radiology specialist evaluated those images using our self-developed Clinical Image Quality Evaluation Chart. Three evaluators classified the overall image quality of the p...

  16. MR neurography of ulnar nerve entrapment at the cubital tunnel: a diffusion tensor imaging study

    Energy Technology Data Exchange (ETDEWEB)

    Breitenseher, Julia B.; Berzaczy, Dominik; Nemec, Stefan F.; Weber, Michael; Prayer, Daniela; Kasprian, Gregor [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Kranz, Gottfried; Sycha, Thomas [Medical University of Vienna, Department of Neurology, Vienna (Austria); Hold, Alina [Medical University of Vienna, Department of Plastic and Reconstructive Surgery, Vienna (Austria)

    2015-07-15

    MR neurography, diffusion tensor imaging (DTI) and tractography at 3 Tesla were evaluated for the assessment of patients with ulnar neuropathy at the elbow (UNE). Axial T2-weighted and single-shot DTI sequences (16 gradient encoding directions) were acquired, covering the cubital tunnel of 46 patients with clinically and electrodiagnostically confirmed UNE and 20 healthy controls. Cross-sectional area (CSA) was measured at the retrocondylar sulcus and FA and ADC values on each section along the ulnar nerve. Three-dimensional nerve tractography and T2-weighted neurography results were independently assessed by two raters. Patients showed a significant reduction of ulnar nerve FA values at the retrocondylar sulcus (p = 0.002) and the deep flexor fascia (p = 0.005). At tractography, a complete or partial discontinuity of the ulnar nerve was found in 26/40 (65 %) of patients. Assessment of T2 neurography was most sensitive in detecting UNE (sensitivity, 91 %; specificity, 79 %), followed by tractography (88 %/69 %). CSA and FA measurements were less effective in detecting UNE. T2-weighted neurography remains the most sensitive MR technique in the imaging evaluation of clinically manifest UNE. DTI-based neurography at 3 Tesla supports the MR imaging assessment of UNE patients by adding quantitative and 3D imaging data. (orig.)

  17. Whole-body MRT imaging. 2. tot. rev. and enl. ed.; Ganzkoerper MR-Tomographie

    Energy Technology Data Exchange (ETDEWEB)

    Rummeny, E.J.; Reimer, P.; Heindel, W. (eds.)

    2006-07-01

    The new edition again presents a comprehensive picture of MR imaging and data acquisition. The reader is enabled to produce her own findings at short notice, and she is supported in understanding and reference. New contents are: Side effects and artefacts; functional MRT imaging of the kidneys; bone marrow and spinal cord imaging; more details on the peripheral skeletal system; whole-body MRT and MRA including 3-Tesla-MR; comparative findings of other imaging procedures; more than 100 tables for higher certainty in differential diagnosis; more than 1000 high-quality images; valuable clinical background information on all indications; summary presentations of the state of knowledge at the end of each chapter as well as specific information on MRT imaging etc. (orig.)

  18. Perinatal clinical and imaging features of CLOVES syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez-Pineda, Israel [Virgen del Rocio Children' s Hospital, Department of Pediatric Surgery, Seville (Spain); Fajardo, Manuel [Virgen del Rocio Children' s Hospital, Department of Pediatric Radiology, Seville (Spain); Chaudry, Gulraiz; Alomari, Ahmad I. [Children' s Hospital Boston and Harvard Medical School, Division of Vascular and Interventional Radiology, Boston, MA (United States)

    2010-08-15

    We report a neonate with antenatal imaging features suggestive of CLOVES syndrome. Postnatal clinical and imaging findings confirmed the diagnosis, with the constellation of truncal overgrowth, cutaneous capillary malformation, lymphatic and musculoskeletal anomalies. The clinical, radiological and histopathological findings noted in this particular phenotype help differentiate it from other overgrowth syndromes with complex vascular anomalies. (orig.)

  19. Multiple-animal MR imaging using a 3T clinical scanner and multi-channel coil for volumetric analysis in a mouse tumor model

    International Nuclear Information System (INIS)

    Multiple small-animal magnetic resonance (MR) imaging to measure tumor volume may increase the throughput of preclinical cancer research assessing tumor response to novel therapies. We used a clinical scanner and multi-channel coil to evaluate the usefulness of this imaging to assess experimental tumor volume in mice. We performed a phantom study to assess 2-dimensional (2D) geometric distortion using 9-cm spherical and 32-cell (8 x 4 one-cm2 grids) phantoms using a 3-tesla clinical MR scanner and dedicated multi-channel coil composed of 16 5-cm circular coils. Employing the multi-channel coil, we simultaneously scanned 6 or 8 mice bearing sarcoma 180 tumors. We estimated tumor volume from the sum of the product of tumor area and slice thickness on 2D spin-echo images (repetition time/echo time, 3500/16 ms; in-plane resolution, 0.195 x 0.195 x 1 mm3). After MR acquisition, we excised and weighed tumors, calculated reference tumor volumes from actual tumor weight assuming a density of 1.05 g/cm3, and assessed the correlation between the estimated and reference volumes using Pearson's test. Two-dimensional geometric distortion was acceptable below 5% in the 9-cm spherical phantom and in every cell in the 32-cell phantom. We scanned up to 8 mice simultaneously using the multi-channel coil and found 11 tumors larger than 0.1 g in 12 mice. Tumor volumes were 1.04±0.73 estimated by MR imaging and 1.04±0.80 cm3 by reference volume (average±standard deviation) and highly correlated (correlation coefficient, 0.995; P<0.01, Pearson's test). Use of multiple small-animal MR imaging employing a clinical scanner and multi-channel coil enabled accurate assessment of experimental tumor volume in a large number of mice and may facilitate high throughput monitoring of tumor response to therapy in preclinical research. (author)

  20. Photoacoustic Imaging in Oncology: Translational Preclinical and Early Clinical Experience.

    Science.gov (United States)

    Valluru, Keerthi S; Wilson, Katheryne E; Willmann, Jürgen K

    2016-08-01

    Photoacoustic imaging has evolved into a clinically translatable platform with the potential to complement existing imaging techniques for the management of cancer, including detection, characterization, prognosis, and treatment monitoring. In photoacoustic imaging, tissue is optically excited to produce ultrasonographic images that represent a spatial map of optical absorption of endogenous constituents such as hemoglobin, fat, melanin, and water or exogenous contrast agents such as dyes and nanoparticles. It can therefore provide functional and molecular information that allows noninvasive soft-tissue characterization. Photoacoustic imaging has matured over the years and is currently being translated into the clinic with various clinical studies underway. In this review, the current state of photoacoustic imaging is presented, including techniques and instrumentation, followed by a discussion of potential clinical applications of this technique for the detection and management of cancer. (©) RSNA, 2016. PMID:27429141

  1. Monitoring of gadolinium-BOPTA uptake into the vessel wall during magnetic resonance (MR)-guided angioplasty of the peripheral arteries with a paclitaxel/gadolinium-BOPTA-coated balloon. An experimental study at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Neizel, M.; Kelm, M. [University Hospital Duesseldorf (Germany). Dept. of Cardiology, Pneumology and Angiology; Ruebben, A.; Weiss, N. [Aachen Resonance, Aachen (Germany); Guenther, R.W. [University Hospital Aachen (Germany). Dept. of Radiology; Krombach, G.A. [University Hospital Giessen (Germany). Dept. of Radiology

    2014-04-15

    Purpose: The success of paclitaxel distribution within the vessel wall during paclitaxel-coated balloon angioplasty to prevent restenosis cannot be monitored under X-ray guidance. The aim of this pilot study was to demonstrate the feasibility of monitoring Gadolinium-BOPTA delivery within the vessel wall during magnetic resonance (MR)-guided paclitaxel/Gadolinium-BOPTA-coated balloon angioplasty of the peripheral arteries. Materials and methods: 6 pigs (47 ± 2 kg) were investigated. All experiments were performed using a 3 Tesla MR scanner. MR-guided bilaterial angioplasty of the iliac arteries was performed using a paclitaxel/MR contrast agent-coated balloon catheter. The feasibility of monitoring the delivery of Gadolinium-BOPTA to the vessel was assessed in 4 animals. In two additional animals, bilateral stenosis was surgically induced in the iliac arteries. Delivery of paclitaxel to the vessel wall was monitored using a 3 D T1-weighted gradient echo (GE) sequence for delineation of the vessel wall. Normalized signal intensity (SI) of the vessel wall was measured before and repeatedly after the intervention for 45 min. in all animals. Results: Paclitaxel/gadolinium-BOPTA-coated balloon angioplasty was successfully accomplished in all iliac arteries (n = 12). In animals with stenosis MR-angiography demonstrated successful dilatation (n = 4). The normalized SI of the vessel wall on T1-weighted GE images significantly increased after the intervention in all animals with and without stenosis for more than 45 min. (p < 0.001). Conclusion: Monitoring of Gadolinium-BOPTA into the vessel wall during MR-guided coated balloon angioplasty is feasible. This is a first step towards providing a tool for the online control of homogenous drug delivery after paclitaxel-coated balloon angioplasty. (orig.)

  2. Chronic and treatment-resistant depression: a study using arterial spin labeling perfusion MRI at 3Tesla.

    OpenAIRE

    Duhameau, Bérengère; Ferré, Jean-Christophe; Jannin, Pierre; Gauvrit, Jean-Yves; Vérin, Marc; Millet, Bruno; Drapier, Dominique

    2010-01-01

    International audience The aim of the present study was to compare patients displaying chronic and treatment-resistant depression with healthy controls, using the resting-state perfusion with arterial spin labeling (ASL) perfusion magnetic resonance imaging (MRI) technique at 3T. The study focused on the subgenual anterior cingulate cortex (sACC), which is a key component in the pathophysiology of depression. Six patients with chronic and treatment-resistant depression and six healthy cont...

  3. A 4-channel 3 Tesla phased array receive coil for awake rhesus monkey fMRI and diffusion MRI experiments

    OpenAIRE

    Khachaturian, Mark Haig

    2010-01-01

    Awake monkey fMRI and diffusion MRI combined with conventional neuroscience techniques has the potential to study the structural and functional neural network. The majority of monkey fMRI and diffusion MRI experiments are performed with single coils which suffer from severe EPI distortions which limit resolution. By constructing phased array coils for monkey MRI studies, gains in SNR and anatomical accuracy (i.e., reduction of EPI distortions) can be achieved using parallel imaging. The major...

  4. Clinical applications of choroidal imaging technologies

    Directory of Open Access Journals (Sweden)

    Jay Chhablani

    2015-01-01

    Full Text Available Choroid supplies the major blood supply to the eye, especially the outer retinal structures. Its understanding has significantly improved with the advent of advanced imaging modalities such as enhanced depth imaging technique and the newer swept source optical coherence tomography. Recent literature reports the findings of choroidal changes, quantitative as well as qualitative, in various chorioretinal disorders. This review article describes applications of choroidal imaging in the management of common diseases such as age-related macular degeneration, high myopia, central serous chorioretinopathy, chorioretinal inflammatory diseases, and tumors. This article briefly discusses future directions in choroidal imaging including angiography.

  5. Clinical anatomy of the canine brain using magnetic resonance imaging.

    Science.gov (United States)

    Leigh, Edmund J; Mackillop, Edward; Robertson, Ian D; Hudson, Lola C

    2008-01-01

    The purpose of this study was to produce an magnetic resonsnce (MR) image atlas of clinically relevant brain anatomy and to relate this neuroanatomy to clinical signs. The brain of a large mixed breed dog was imaged in transverse, sagittal, and dorsal planes using a 1.5 T MR unit and the following pulse sequences: Turbo (fast) spin echo (TSE) T2, T1, and T2- weighted spatial and chemical shift-encoded excitation sequence. Relevant neuroanatomic structures were identified using anatomic texts, sectioned cadaver heads, and previously published atlases. Major subdivisions of the brain were mapped and the neurologic signs of lesions in these divisions were described. TSE T2-weighted images were found to be the most useful for identifying clinically relevant neuroanatomy. Relating clinical signs to morphology as seen on MR will assist veterinarians to better understand clinically relevant neuroanatomy in MR images. PMID:18418990

  6. Vertigo Imaging; Clinical Radiology'

    Directory of Open Access Journals (Sweden)

    Jalal Jalal Shokouhi

    2009-01-01

    ;' and anxiety in psychiatry. "n- Clinical differentiating of peripheral and central vestibular lesion should be done by separating harmonic and disharmonic vestibular syndrome. "n- Examination of the patient with vertigo '' laboratory and imaging'' "n•Electronystagmography "n•Video-oculography "n•Audiometry "n•BAEP "n•CT "n•MRI "n - Common cause of vertigo '' all by image '' "nPeripheral: Physiological '' motion sickness'', benign paroxysmal positional vertigo , vestibular neuronitis , labyrinthitis , meniere disease , perilymph fistula. "nCentral: Brain stem TIA/infarct , post. fossa tumors , M.sclerosis, syringobulbia ,Arnold -chiari , temporal lobe epilepsy and basilar migraine. "nOthers: Cardiac , GI , psycogenic , mediacations , anemia and  hypotension , toxin and drugs: "n''aminoglycoside antibiotics,anticonvulsants,salycilates , alcohol , sedatives , antihistamins , antidepressants '' , cervical spondylosis , sensory deprivation ''neuropathy , visual impairment '',anemia , hypoglycemia , orthostatic hypotension and hyperventilation.  

  7. Ultrasound Image Quality Assessment: A framework for evaluation of clinical image quality

    DEFF Research Database (Denmark)

    Hemmsen, Martin Christian; Pedersen, Mads Møller; Nikolov, Svetoslav Ivanov;

    2010-01-01

    Improvement of ultrasound images should be guided by their diagnostic value. Evaluation of clinical image quality is generally performed subjectively, because objective criteria have not yet been fully developed and accepted for the evaluation of clinical image quality. Based on recommendation 500...... and is applicable for clinical use. The free access to all system parameters enables the ability to capture standardized images as found in the clinic and experimental data from new processing or beamformation methods. The length of the data sequences is only restricted by the memory of the external PC. Data may...

  8. High frame rate photoacoustic imaging using clinical ultrasound system

    Science.gov (United States)

    Sivasubramanian, Kathyayini; Pramanik, Manojit

    2016-03-01

    Photoacoustic tomography (PAT) is a potential hybrid imaging modality which is gaining attention in the field of medical imaging. Typically a Q-switched Nd:YAG laser is used to excite the tissue and generate photoacoustic signals. But, they are not suitable for clinical applications owing to their high cost, large size. Also, their low pulse repetition rate (PRR) of few tens of hertz prevents them from being used in real-time PAT. So, there is a growing need for an imaging system capable of real-time imaging for various clinical applications. In this work, we are using a nanosecond pulsed laser diode as an excitation source and a clinical ultrasound imaging system to obtain the photoacoustic imaging. The excitation laser is ~803 nm in wavelength with energy of ~1.4 mJ per pulse. So far, the reported frame rate for photoacoustic imaging is only a few hundred Hertz. We have demonstrated up to 7000 frames per second framerate in photoacoustic imaging (B-mode) and measured the flow rate of fast moving obje ct. Phantom experiments were performed to test the fast imaging capability and measure the flow rate of ink solution inside a tube. This fast photoacoustic imaging can be used for various clinical applications including cardiac related problems, where the blood flow rate is quite high, or other dynamic studies.

  9. Differentiation of true anophthalmia from clinical anophthalmia using neuroradiological imaging

    Institute of Scientific and Technical Information of China (English)

    Ali; Riza; Cenk; Celebi; Hadi; Sasani

    2014-01-01

    Anophthalmia is a condition of the absence of an eye and the presence of a small eye within the orbit.It is associated with many known syndromes.Clinical findings,as well as imaging modalities and genetic analysis,are important in making the diagnosis.Imaging modalities are crucial scanning methods.Cryptophthalmos,cyclopia,synophthalmia and congenital cystic eye should be considered in differential diagnoses.We report two clinical anophthalmic siblings,emphasizing the importance of neuroradiological and orbital imaging findings in distinguishing true congenital anophthalmia from clinical anophthalmia.

  10. Hepatic Iron Quantification on 3 Tesla (3 T Magnetic Resonance (MR: Technical Challenges and Solutions

    Directory of Open Access Journals (Sweden)

    Muhammad Anwar

    2013-01-01

    Full Text Available MR has become a reliable and noninvasive method of hepatic iron quantification. Currently, most of the hepatic iron quantification is performed on 1.5 T MR, and the biopsy measurements have been paired with R2 and R2* values for 1.5 T MR. As the use of 3 T MR scanners is steadily increasing in clinical practice, it has become important to evaluate the practicality of calculating iron burden at 3 T MR. Hepatic iron quantification on 3 T MR requires a better understanding of the process and more stringent technical considerations. The purpose of this work is to focus on the technical challenges in establishing a relationship between T2* values at 1.5 T MR and 3 T MR for hepatic iron concentration (HIC and to develop an appropriately optimized MR protocol for the evaluation of T2* values in the liver at 3 T magnetic field strength. We studied 22 sickle cell patients using multiecho fast gradient-echo sequence (MFGRE 3 T MR and compared the results with serum ferritin and liver biopsy results. Our study showed that the quantification of hepatic iron on 3 T MRI in sickle cell disease patients correlates well with clinical blood test results and biopsy results. 3 T MR liver iron quantification based on MFGRE can be used for hepatic iron quantification in transfused patients.

  11. Assessing liver function by liver enhancement during the hepatobiliary phase with Gd-EOB-DTPA-enhanced MRI at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Verloh, N.; Haimerl, M.; Schlabeck, M.; Schreyer, A.G.; Stroszczynski, C.; Fellner, C.; Wiggermann, P. [University Hospital Regensburg, Department of Radiology, Regensburg (Germany); Zeman, F. [University Hospital Regensburg, Center for Clinical Trials, Regensburg (Germany); Barreiros, A. [University Hospital Regensburg, Department of Gastroenterology, Regensburg (Germany); Loss, M. [University Hospital Regensburg, Department of Surgery, Regensburg (Germany)

    2014-05-15

    The purpose of this study was to evaluate the usefulness of Gd-EOB-DTPA-enhanced 3-T MRI to determine the hepatic functional reserve expressed by the model for end-stage liver disease (MELD) score. A total of 121 patients with normal liver function (NLF; MELD score ≤ 10) and 29 patients with impaired liver function (ILF; MELD score > 10) underwent contrast-enhanced MRI with a hepatocyte-specific contrast agent at 3T. T1-weighted volume interpolated breath-hold examination (VIBE) sequences with fat suppression were acquired before and 20 min after contrast injection. Relative enhancement (RE) between plain signal intensity and contrast-enhanced signal intensity was calculated and was used to determine Gd-EOB-DTPA uptake into the liver parenchyma for patients with different MELD scores. RE differed significantly (p ≤ 0.001) between patients with NLF (87.2 ± 29.5 %) and patients with ILF (45.4 ± 26.5 %). The optimal cut-off value for RE to differentiate NLF from ILF was 47.7 % (AUC 0.87). This cut-off value showed a sensitivity of 82.8 % and a specificity of 92.7 % for the differentiation of the analysed groups. Gd-EOB-DTPA uptake in hepatocytes is strongly affected by liver function. Gd-EOB-DTPA-enhanced MRI and assessment of RE during the hepatobiliary phase (HBP) may serve as a useful image-based test in liver imaging for determining regional and global liver function. (orig.)

  12. PET Imaging - from Physics to Clinical Molecular Imaging

    Science.gov (United States)

    Majewski, Stan

    2008-03-01

    From the beginnings many years ago in a few physics laboratories and first applications as a research brain function imager, PET became lately a leading molecular imaging modality used in diagnosis, staging and therapy monitoring of cancer, as well as has increased use in assessment of brain function (early diagnosis of Alzheimer's, etc) and in cardiac function. To assist with anatomic structure map and with absorption correction CT is often used with PET in a duo system. Growing interest in the last 5-10 years in dedicated organ specific PET imagers (breast, prostate, brain, etc) presents again an opportunity to the particle physics instrumentation community to contribute to the important field of medical imaging. In addition to the bulky standard ring structures, compact, economical and high performance mobile imagers are being proposed and build. The latest development in standard PET imaging is introduction of the well known TOF concept enabling clearer tomographic pictures of the patient organs. Development and availability of novel photodetectors such as Silicon PMT immune to magnetic fields offers an exciting opportunity to use PET in conjunction with MRI and fMRI. As before with avalanche photodiodes, particle physics community plays a leading role in developing these devices. The presentation will mostly focus on present and future opportunities for better PET designs based on new technologies and methods: new scintillators, photodetectors, readout, software.

  13. Magnetic resonance imaging in clinically-definite multiple sclerosis

    International Nuclear Information System (INIS)

    Forty-two patients with clinically-definite multiple sclerosis were examined by magnetic resonance imaging using a 1.5-T instrument. Magnetic resonance imaging detected an abnormality in 90% of patients. In four patients, no lesions were demonstrated. The number, size and site of the lesions by magnetic resonance imaging were compared with the patients' clinical status and other variables. The Kurtzke disability status scale score increased in patients with corpus callosum atrophy, brainstem and basal ganglia lesions, and correlated with the total number of lesions. No correlation was shown between the findings of magnetic resonance imaging and disease duration, age, sex or pattern-reversal visual-evoked potentials. The variety of magnetic resonance images that could be obtained in patients with clinically-definite multiple sclerosis is highlighted. 24 refs., 8 figs., 1 tab

  14. Measurement of the weighted peak level for occupational exposure to gradient magnetic fields for 1.5 and 3 Tesla MRI body scanners

    International Nuclear Information System (INIS)

    The purpose of this work is to give a contribution to the construction of a comprehensive knowledge of the exposure levels to gradient magnetic fields (GMF) in terms of the weighed peak (WP), especially for 3 Tesla scanners for which there are still few works available in the literature. A new generation probe for the measurement of electromagnetic fields in the range of 1 Hz-400 kHz was used to assess the occupational exposure levels to the GMF for 1.5 and 3.0 Tesla MRI body scanners, using the method of the WP according to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) approach. The probe was placed at a height of 1.1 m, close to the MRI scanners, where operators could stay during some medical procedures with particular issues. The measurements were performed for a set of typical acquisition sequences for body (liver) and head exams. The measured values of WP were in compliance with ICNIRP 2010 reference levels for occupational exposures. (authors)

  15. Measurement of the weighted peak level for occupational exposure to gradient magnetic fields for 1.5 and 3 Tesla MRI body scanners.

    Science.gov (United States)

    Bonutti, F; Tecchio, M; Maieron, M; Trevisan, D; Negro, C; Calligaris, F

    2016-03-01

    The purpose of this work is to give a contribution to the construction of a comprehensive knowledge of the exposure levels to gradient magnetic fields (GMF) in terms of the weighed peak (WP), especially for 3 Tesla scanners for which there are still few works available in the literature. A new generation probe for the measurement of electromagnetic fields in the range of 1 Hz-400 kHz was used to assess the occupational exposure levels to the GMF for 1.5 and 3.0 Tesla MRI body scanners, using the method of the WP according to the International Commission on Non-Ionizing Radiation Protection (ICNIRP) approach. The probe was placed at a height of 1.1 m, close to the MRI scanners, where operators could stay during some medical procedures with particular issues. The measurements were performed for a set of typical acquisition sequences for body (liver) and head exams. The measured values of WP were in compliance with ICNIRP 2010 reference levels for occupational exposures.

  16. Functional imaging in head and neck squamous cell carcinoma: correlation of PET/CT and diffusion-weighted imaging at 3 Tesla

    International Nuclear Information System (INIS)

    The purposes of this study were: (a) to prospectively assess the correlation between apparent diffusion coefficient (ADC) values and maximum standardized uptake values (SUVmax) in patients with head and neck squamous cell carcinomas (SCC); and (b) to assess ADC and SUVmax values in relation to different tumour grades and stages in our patient population. The study group comprised 31 consecutive patients with biopsy-proven head and neck squamous cell carcinoma who were examined using a 3T MRI scanner with a 16-channel head and neck coil. In addition to routine sequences, axial (DWIBS) and sagittal (DW-EPI) diffusion-weighted sequences were obtained using b-values of 0 mm2/s and 800 mm2/s. The ADC maps were calculated automatically. The ADC values of the tumours were measured with three regions of interest (ROIs) of standard size, and an ROI covering the entire tumour. In all patients, contrast-enhanced, whole-body 18F-FDG PET/CT was performed within 2 weeks of the MRI examination. SUVmax was measured for every tumour using a 3-D freehand ROI that covered the entire tumour. Two-way repeated measures ANOVA was used for group comparisons. The Spearman rank correlation test was performed for ADC values. Mean ADC values in the 31 SCC were 0.902 (±0.134) with a ROI of standard size, and 0.928 (±0.160) with the large ROI measurements on the axial DWIBS sequence. The ADC values of the tumours were significantly higher when measured with the sagittal DW-EPI sequence: 1.051 (±0.211) and 1.082 (±0.208). We observed no significant differences in ADC values and SUVmax between the various T stages or histological grades of the tumours. SUVmax values (26.5±12) did not correlate with ADC values on DWIBS or EPI. There is no correlation between the FDG uptake and the ADC value in head and neck SCC. The three different tumour grades and four tumour stages present in our study population could not be differentiated based on ADC values or SUV. (orig.)

  17. Functional imaging in head and neck squamous cell carcinoma: correlation of PET/CT and diffusion-weighted imaging at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Fruehwald-Pallamar, Julia; Czerny, Christian; Mayerhoefer, Marius E.; Weber, Michael; Fruehwald, Laura; Herneth, Andreas M. [Medical University of Vienna, Department of Radiology, Vienna (Austria); Halpern, Benjamin S. [Medical University of Vienna, Department of Radiology, Vienna (Austria); Harvard Medical School, Department of Nuclear Medicine, Brigham and Women' s Hospital, Boston, MA (United States); Eder-Czembirek, Christina [Medical University of Vienna, University Hospital for Cranio, Maxillofacial and Oral Surgery, Vienna (Austria); Brunner, Markus [Medical University of Vienna, Department of Otorhinolaryngology, Head and Neck Surgery, Vienna (Austria); Schuetz, Matthias [Medical University of Vienna, Department of Nuclear Medicine, Vienna (Austria)

    2011-06-15

    The purposes of this study were: (a) to prospectively assess the correlation between apparent diffusion coefficient (ADC) values and maximum standardized uptake values (SUVmax) in patients with head and neck squamous cell carcinomas (SCC); and (b) to assess ADC and SUVmax values in relation to different tumour grades and stages in our patient population. The study group comprised 31 consecutive patients with biopsy-proven head and neck squamous cell carcinoma who were examined using a 3T MRI scanner with a 16-channel head and neck coil. In addition to routine sequences, axial (DWIBS) and sagittal (DW-EPI) diffusion-weighted sequences were obtained using b-values of 0 mm{sup 2}/s and 800 mm{sup 2}/s. The ADC maps were calculated automatically. The ADC values of the tumours were measured with three regions of interest (ROIs) of standard size, and an ROI covering the entire tumour. In all patients, contrast-enhanced, whole-body {sup 18}F-FDG PET/CT was performed within 2 weeks of the MRI examination. SUVmax was measured for every tumour using a 3-D freehand ROI that covered the entire tumour. Two-way repeated measures ANOVA was used for group comparisons. The Spearman rank correlation test was performed for ADC values. Mean ADC values in the 31 SCC were 0.902 ({+-}0.134) with a ROI of standard size, and 0.928 ({+-}0.160) with the large ROI measurements on the axial DWIBS sequence. The ADC values of the tumours were significantly higher when measured with the sagittal DW-EPI sequence: 1.051 ({+-}0.211) and 1.082 ({+-}0.208). We observed no significant differences in ADC values and SUVmax between the various T stages or histological grades of the tumours. SUVmax values (26.5{+-}12) did not correlate with ADC values on DWIBS or EPI. There is no correlation between the FDG uptake and the ADC value in head and neck SCC. The three different tumour grades and four tumour stages present in our study population could not be differentiated based on ADC values or SUV. (orig.)

  18. Liver imaging. Clinical applications and future perspectives

    International Nuclear Information System (INIS)

    Primary hepatocellular carcinoma and liver metastases affect several millon people each year. The main imaging modalities to detect and assist diagnosis of primary and secondary liver tumours include MR imaging, CT, and US. The value of these techniques is further increased by the use of contrast agents which increase the sensitivity, and sometimes also the specificity, of the investigations. The relative advantages and drawbacks of the different contrast agents and imaging modalities in the detection and characterisation of liver tumours are discussed. Currently there is no consensus amongst investigators as to which is superior, due to the technical complexities and number of combinations possible within each of the different modalities. There continues to be advances in the hardware and software of imaging equipment, as well as a trend to develop new contrast agents with more organ-specificity. These include those targeting the hepatocytes, such as mangafodipir trisodium (MnDPDP, Teslascan), and those with reticuloendothelial cell specificity, such as the superparamagnetic iron oxides. These developments have the potential for making significant contributions to the diagnostic value of imaging procedures and, by reducing the number of investigations necessary to reach a final diagnosis, having a significant and beneficial impact on the pharmaco-economics of patient health care. (orig.)

  19. Clinical skin imaging using color spatial frequency domain imaging (Conference Presentation)

    Science.gov (United States)

    Yang, Bin; Lesicko, John; Moy, Austin J.; Reichenberg, Jason; Tunnell, James W.

    2016-02-01

    Skin diseases are typically associated with underlying biochemical and structural changes compared with normal tissues, which alter the optical properties of the skin lesions, such as tissue absorption and scattering. Although widely used in dermatology clinics, conventional dermatoscopes don't have the ability to selectively image tissue absorption and scattering, which may limit its diagnostic power. Here we report a novel clinical skin imaging technique called color spatial frequency domain imaging (cSFDI) which enhances contrast by rendering color spatial frequency domain (SFD) image at high spatial frequency. Moreover, by tuning spatial frequency, we can obtain both absorption weighted and scattering weighted images. We developed a handheld imaging system specifically for clinical skin imaging. The flexible configuration of the system allows for better access to skin lesions in hard-to-reach regions. A total of 48 lesions from 31 patients were imaged under 470nm, 530nm and 655nm illumination at a spatial frequency of 0.6mm^(-1). The SFD reflectance images at 470nm, 530nm and 655nm were assigned to blue (B), green (G) and red (R) channels to render a color SFD image. Our results indicated that color SFD images at f=0.6mm-1 revealed properties that were not seen in standard color images. Structural features were enhanced and absorption features were reduced, which helped to identify the sources of the contrast. This imaging technique provides additional insights into skin lesions and may better assist clinical diagnosis.

  20. Accuracy of 3 Tesla pelvic phased-array multiparametric MRI in diagnosing prostate cancer at repeat biopsy

    Directory of Open Access Journals (Sweden)

    Pietro Pepe

    2014-12-01

    Full Text Available Introduction. Multiparametric pelvic magnetic resonance imaging (mpMRI accuracy in prostate cancer (PCa diagnosis was evaluated. Materials and Methods. From June 2011 to December 2013, 168 patients (median 65 years with negative digital rectal examination underwent repeat transperineal saturation biopsy (SPBx; median 28 cores for persistently high or increasing PSA values, PSA >10 ng/ml or PSA values between 4.1-10 o r 2.6-4 ng/ml with free/total PSA < 25% and < 20%, respectively. All patients underwent mpMRI using a 3.0 Tesla scanner equipped with surface 16 channels phased-array coil and lesions suspicious for PCa were submitted to additional targeted biopsies. Results. A T1c PCa was found in 66 (39% cases; SPBx and mpMRI-suspicious targeted biopsy diagnosed 60 (91% and 52 (78.8% cancers missing 6 (all of the anterior zone and 14 cancers (12 and 2 of the lateral margins and anterior zone, respectively; in detail, mpMRI missed 12 (18.1% PCa charaterized by microfocal (1 positive core with greatest percentage of cancer and Gleason score equal to 5% and 6, respectively disease at risk for insignificant cancer. The diameter of the suspicious mpMRI lesion was directly correlated to the diagnosis of PCa with poor Gleason score (p < 0.05; detection rate of cancer for each suspicious mpMRI core was 35.3%. Diagnostic accuracy, sensitivity, specificity, positive and negative predictive value of mpMRI in diagnosing PCa was 75.7%, 82.5%, 71.8%, 78.9%, 87.9%, respectively. Conclusion. Multiparametric pMRI improved SPBx accuracy in diagnosing significant anterior PCa; the diameter of mpMRI suspicious lesion resulted significantly predictive of aggressive cancers.

  1. Clinics in diagnostic imaging (58). Chronic cerebral paragonimiasis.

    Science.gov (United States)

    Kaw, G J; Sitoh, Y Y

    2001-02-01

    A 36-year-old Korean man presented with a history of epilepsy. MR imaging of the brain revealed multiple conglomerated round nodules that were hypointense on both T1-and-T2 weighted images. These were located at the left temporal and occipital lobes and had surrounding encephalomalacia. CT scan confirmed the presence of large calcified nodules in the corresponding regions. These imaging findings were typical of chronic cerebral paragonimiasis. The clinical, CT and MR features of cerebral paragonimiasis are reviewed.

  2. Preoperative Imaging for Clinical Staging Prior to Radical Cystectomy.

    Science.gov (United States)

    Hugen, Cory M; Duddalwar, Vinay; Daneshmand, Siamak

    2016-09-01

    The importance of patient selection for quality outcomes following radical cystectomy is critical. Clinical staging is one of the key elements necessary for patient selection, and staging relies on accurate preoperative imaging. Many imaging modalities are available and have been utilized for preoperative staging with published operating characteristics. In this update, we review recently published literature for advances in preoperative imaging prior to radical cystectomy. PMID:27432379

  3. Multimodal imaging of bone metastases: From preclinical to clinical applications

    Directory of Open Access Journals (Sweden)

    Stephan Ellmann

    2015-10-01

    Full Text Available Metastases to the skeletal system are commonly observed in cancer patients, highly affecting the patients' quality of life. Imaging plays a major role in detection, follow-up, and molecular characterisation of metastatic disease. Thus, imaging techniques have been optimised and combined in a multimodal and multiparametric manner for assessment of complementary aspects in osseous metastases. This review summarises both application of the most relevant imaging techniques for bone metastasis in preclinical models and the clinical setting.

  4. Clinical value of ventilation perfusion imaging for pulmonary embolism

    International Nuclear Information System (INIS)

    The results and clinical value of ventilation perfusion (VP) imaging in 434 patients is reported. Pulmonary arteriography has been performed independently in 47 of these patients. Pulmonary arteriography provides the only specific test for intraluminal thrombus in pulmonary vessels. It is, however, invasive, time consuming and expensive, and has a significant morbidity and occasional mortality. For these reasons, VP imaging has been widely adopted as a screening test for pulmonary embolism (PE). The non-specific nature of perfusion abnormalities of lung demonstrated by this technique are a drawback, and controversy has been generated concerning the value of VP imaging to clinicians who must make decisions on clinical management. It is found that VP imaging provides valuable information in two-thirds of all patients referred to Nuclear Medicine with a clinical suspicion of PE. Among these patients, VP imaging confirmed the clinical suspicion in one-third, clarified or corrected the clinical diagnosis in one-third, and was non-diagnostic in one-third. It is concluded that VP imaging is a safe, reliable and valuable screening test in a significant number of patients suspected of having PE

  5. Automated spectral imaging for clinical diagnostics

    Science.gov (United States)

    Breneman, John; Heffelfinger, David M.; Pettipiece, Ken; Tsai, Chris; Eden, Peter; Greene, Richard A.; Sorensen, Karen J.; Stubblebine, Will; Witney, Frank

    1998-04-01

    Bio-Rad Laboratories supplies imaging equipment for many applications in the life sciences. As part of our effort to offer more flexibility to the investigator, we are developing a microscope-based imaging spectrometer for the automated detection and analysis of either conventionally or fluorescently labeled samples. Immediate applications will include the use of fluorescence in situ hybridization (FISH) technology. The field of cytogenetics has benefited greatly from the increased sensitivity of FISH producing simplified analysis of complex chromosomal rearrangements. FISH methods for identification lends itself to automation more easily than the current cytogenetics industry standard of G- banding, however, the methods are complementary. Several technologies have been demonstrated successfully for analyzing the signals from labeled samples, including filter exchanging and interferometry. The detection system lends itself to other fluorescent applications including the display of labeled tissue sections, DNA chips, capillary electrophoresis or any other system using color as an event marker. Enhanced displays of conventionally stained specimens will also be possible.

  6. A comparison between magnetic resonance angiography at 3 teslas (time-of-flight and contrast-enhanced and flat-panel digital subtraction angiography in the assessment of embolized brain aneurysms

    Directory of Open Access Journals (Sweden)

    Guilherme S. Nakiri

    2011-01-01

    Full Text Available PURPOSE: To compare the time-of-flight and contrast-enhanced- magnetic resonance angiography techniques in a 3 Tesla magnetic resonance unit with digital subtraction angiography with the latest flat-panel technology and 3D reconstruction in the evaluation of embolized cerebral aneurysms. INTRODUCTION: Many embolized aneurysms are subject to a recurrence of intra-aneurismal filling. Traditionally, imaging surveillance of coiled aneurysms has consisted of repeated digital subtraction angiography. However, this method has a small but significant risk of neurological complications, and many authors have advocated the use of noninvasive imaging methods for the surveillance of embolized aneurysms. METHODS: Forty-three aneurysms in 30 patients were studied consecutively between November 2009 and May 2010. Two interventional neuroradiologists rated the time-of-flight-magnetic resonance angiography, the contrast-enhanced-magnetic resonance angiography, and finally the digital subtraction angiography, first independently and then in consensus. The status of aneurysm occlusion was assessed according to the Raymond scale, which indicates the level of recanalization according to degrees: Class 1: excluded aneurysm; Class 2: persistence of a residual neck; Class 3: persistence of a residual aneurysm. The agreement among the analyses was assessed by applying the Kappa statistic. RESULTS: Inter-observer agreement was excellent for both methods (K = 0.93; 95 % CI: 0.84-1. Inter-technical agreement was almost perfect between time-of-flight-magnetic resonance angiography and digital subtraction angiography (K = 0.98; 95 % CI: 0.93-1 and between time-of-flight-magnetic resonance angiography and contrast-enhanced-magnetic resonance angiography (K = 0.98; 95% CI: 0.93-1. Disagreement occurred in only one case (2.3%, which was classified as Class I by time-of-flight-magnetic resonance angiography and Class II by digital subtraction angiography. The agreement between

  7. Imaging and Data Acquisition in Clinical Trials for Radiation Therapy.

    Science.gov (United States)

    FitzGerald, Thomas J; Bishop-Jodoin, Maryann; Followill, David S; Galvin, James; Knopp, Michael V; Michalski, Jeff M; Rosen, Mark A; Bradley, Jeffrey D; Shankar, Lalitha K; Laurie, Fran; Cicchetti, M Giulia; Moni, Janaki; Coleman, C Norman; Deye, James A; Capala, Jacek; Vikram, Bhadrasain

    2016-02-01

    Cancer treatment evolves through oncology clinical trials. Cancer trials are multimodal and complex. Assuring high-quality data are available to answer not only study objectives but also questions not anticipated at study initiation is the role of quality assurance. The National Cancer Institute reorganized its cancer clinical trials program in 2014. The National Clinical Trials Network (NCTN) was formed and within it was established a Diagnostic Imaging and Radiation Therapy Quality Assurance Organization. This organization is Imaging and Radiation Oncology Core, the Imaging and Radiation Oncology Core Group, consisting of 6 quality assurance centers that provide imaging and radiation therapy quality assurance for the NCTN. Sophisticated imaging is used for cancer diagnosis, treatment, and management as well as for image-driven technologies to plan and execute radiation treatment. Integration of imaging and radiation oncology data acquisition, review, management, and archive strategies are essential for trial compliance and future research. Lessons learned from previous trials are and provide evidence to support diagnostic imaging and radiation therapy data acquisition in NCTN trials.

  8. Clinical image: MRI during migraine with aura

    Energy Technology Data Exchange (ETDEWEB)

    McNeal, A.C. [Brooklyn VA Medical Center, NY (United States)

    1996-03-01

    Migraine refers to severe headaches that are usually unilateral, throbbing, and associated with nausea, vomiting, photophobia, and phonophobia. Migraine with aura (formerly called {open_quotes}classic migraine{close_quotes}) consists of the headache preceded or accompanied by neurological dysfunction. This dysfunction (aura) usually involves visual and sensory symptoms. The patient described herein experienced migraine with aura. MRI during and after the attack showed a reversible abnormality of the right posterior cerebral artery, with no parenchymal lesions. This appears to be the first report of abnormal MR vascular imaging during migraine with aura. 10 refs., 2 figs.

  9. Clinical application of functional magnetic resonance imaging

    CERN Document Server

    Alwatban, A Z W

    2002-01-01

    The work described in this thesis was carried out at the Magnetic Resonance Centre of the University of Nottingham during the time from May 1998 to April 2001, and is the work of the except where indicated by reference. The main source of signal changes in functional magnetic resonance imaging (fMRJ) is the fluctuation of paramagnetic deoxyhaemoglobin in the venous blood during different states of functional performance. For the work of this thesis, fMRI studies were carried out using a 3 T MR system with an echo planar imaging (EPI) pulse sequence. Hearing research utilising fMRI has been previously reported in normal subjects. Hearing fMRI is normally performed by stimulating the auditory cortex via an acoustic task presentation such as music, tone, etc. However, performing the same research on deaf subjects requires special equipment to be designed to allow direct stimulation of the auditory nerve. In this thesis, a new method of direct electrical stimulation of the auditory nerve is described that uses a ...

  10. Multispectral photoacoustic imaging of nerves with a clinical ultrasound system

    Science.gov (United States)

    Mari, Jean Martial; West, Simeon; Beard, Paul C.; Desjardins, Adrien E.

    2014-03-01

    Accurate and efficient identification of nerves is of great importance during many ultrasound-guided clinical procedures, including nerve blocks and prostate biopsies. It can be challenging to visualise nerves with conventional ultrasound imaging, however. One of the challenges is that nerves can have very similar appearances to nearby structures such as tendons. Several recent studies have highlighted the potential of near-infrared optical spectroscopy for differentiating nerves and adjacent tissues, as this modality can be sensitive to optical absorption of lipids that are present in intra- and extra-neural adipose tissue and in the myelin sheaths. These studies were limited to point measurements, however. In this pilot study, a custom photoacoustic system with a clinical ultrasound imaging probe was used to acquire multi-spectral photoacoustic images of nerves and tendons from swine ex vivo, across the wavelength range of 1100 to 1300 nm. Photoacoustic images were processed and overlaid in colour onto co-registered conventional ultrasound images that were acquired with the same imaging probe. A pronounced optical absorption peak centred at 1210 nm was observed in the photoacoustic signals obtained from nerves, and it was absent in those obtained from tendons. This absorption peak, which is consistent with the presence of lipids, provides a novel image contrast mechanism to significantly enhance the visualization of nerves. In particular, image contrast for nerves was up to 5.5 times greater with photoacoustic imaging (0.82 +/- 0.15) than with conventional ultrasound imaging (0.148 +/- 0.002), with a maximum contrast of 0.95 +/- 0.02 obtained in photoacoustic mode. This pilot study demonstrates the potential of photoacoustic imaging to improve clinical outcomes in ultrasound-guided interventions in regional anaesthesia and interventional oncology.

  11. Clinical application of functional magnetic resonance imaging

    International Nuclear Information System (INIS)

    The work described in this thesis was carried out at the Magnetic Resonance Centre of the University of Nottingham during the time from May 1998 to April 2001, and is the work of the author except where indicated by reference. The main source of signal changes in functional magnetic resonance imaging (fMRJ) is the fluctuation of paramagnetic deoxyhaemoglobin in the venous blood during different states of functional performance. For the work of this thesis, fMRI studies were carried out using a 3 T MR system with an echo planar imaging (EPI) pulse sequence. Hearing research utilising fMRI has been previously reported in normal subjects. Hearing fMRI is normally performed by stimulating the auditory cortex via an acoustic task presentation such as music, tone, etc. However, performing the same research on deaf subjects requires special equipment to be designed to allow direct stimulation of the auditory nerve. In this thesis, a new method of direct electrical stimulation of the auditory nerve is described that uses a transtympanic electrode implanted onto the surface of the cochlea. This approach would however, result in electromotive forces (EMFs) being induced by the time varying magnetic field, which would lead to current flow and heating, as well as deflection of the metallic electrode within the static magnetic field, and image distortion due to the magnetic susceptibility difference. A gold-plated tungsten electrode with a zero magnetic susceptibility was developed to avoid image distortion. Used with carbon leads and a carbon reference pad, it enabled safe, distortion-free fMRI studies of deaf subjects. The study revealed activation of the primary auditory cortex. This fMRI procedure can be used to demonstrate whether the auditory pathway is fully intact, and may provide a useful method for pre-operative assessment of candidates for cochlear implantation. Glucose is the energy source on which the function of the human brain is entirely dependent. Failure to

  12. Clinical application of functional magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Alwatban, Adnan Z.W

    2002-07-01

    The work described in this thesis was carried out at the Magnetic Resonance Centre of the University of Nottingham during the time from May 1998 to April 2001, and is the work of the author except where indicated by reference. The main source of signal changes in functional magnetic resonance imaging (fMRJ) is the fluctuation of paramagnetic deoxyhaemoglobin in the venous blood during different states of functional performance. For the work of this thesis, fMRI studies were carried out using a 3 T MR system with an echo planar imaging (EPI) pulse sequence. Hearing research utilising fMRI has been previously reported in normal subjects. Hearing fMRI is normally performed by stimulating the auditory cortex via an acoustic task presentation such as music, tone, etc. However, performing the same research on deaf subjects requires special equipment to be designed to allow direct stimulation of the auditory nerve. In this thesis, a new method of direct electrical stimulation of the auditory nerve is described that uses a transtympanic electrode implanted onto the surface of the cochlea. This approach would however, result in electromotive forces (EMFs) being induced by the time varying magnetic field, which would lead to current flow and heating, as well as deflection of the metallic electrode within the static magnetic field, and image distortion due to the magnetic susceptibility difference. A gold-plated tungsten electrode with a zero magnetic susceptibility was developed to avoid image distortion. Used with carbon leads and a carbon reference pad, it enabled safe, distortion-free fMRI studies of deaf subjects. The study revealed activation of the primary auditory cortex. This fMRI procedure can be used to demonstrate whether the auditory pathway is fully intact, and may provide a useful method for pre-operative assessment of candidates for cochlear implantation. Glucose is the energy source on which the function of the human brain is entirely dependent. Failure to

  13. An adaptive optics imaging system designed for clinical use.

    Science.gov (United States)

    Zhang, Jie; Yang, Qiang; Saito, Kenichi; Nozato, Koji; Williams, David R; Rossi, Ethan A

    2015-06-01

    Here we demonstrate a new imaging system that addresses several major problems limiting the clinical utility of conventional adaptive optics scanning light ophthalmoscopy (AOSLO), including its small field of view (FOV), reliance on patient fixation for targeting imaging, and substantial post-processing time. We previously showed an efficient image based eye tracking method for real-time optical stabilization and image registration in AOSLO. However, in patients with poor fixation, eye motion causes the FOV to drift substantially, causing this approach to fail. We solve that problem here by tracking eye motion at multiple spatial scales simultaneously by optically and electronically integrating a wide FOV SLO (WFSLO) with an AOSLO. This multi-scale approach, implemented with fast tip/tilt mirrors, has a large stabilization range of ± 5.6°. Our method consists of three stages implemented in parallel: 1) coarse optical stabilization driven by a WFSLO image, 2) fine optical stabilization driven by an AOSLO image, and 3) sub-pixel digital registration of the AOSLO image. We evaluated system performance in normal eyes and diseased eyes with poor fixation. Residual image motion with incremental compensation after each stage was: 1) ~2-3 arc minutes, (arcmin) 2) ~0.5-0.8 arcmin and, 3) ~0.05-0.07 arcmin, for normal eyes. Performance in eyes with poor fixation was: 1) ~3-5 arcmin, 2) ~0.7-1.1 arcmin and 3) ~0.07-0.14 arcmin. We demonstrate that this system is capable of reducing image motion by a factor of ~400, on average. This new optical design provides additional benefits for clinical imaging, including a steering subsystem for AOSLO that can be guided by the WFSLO to target specific regions of interest such as retinal pathology and real-time averaging of registered images to eliminate image post-processing.

  14. Modern Trends in Imaging X: Spectral Imaging in Preclinical Research and Clinical Pathology

    Directory of Open Access Journals (Sweden)

    Richard Levenson

    2012-01-01

    Full Text Available Spectral imaging methods are attracting increased interest from researchers and practitioners in basic science, pre-clinical and clinical arenas. A combination of better labeling reagents and better optics creates opportunities to detect and measure multiple parameters at the molecular and cellular level. These tools can provide valuable insights into the basic mechanisms of life, and yield diagnostic and prognostic information for clinical applications. There are many multispectral technologies available, each with its own advantages and limitations. This chapter will present an overview of the rationale for spectral imaging, and discuss the hardware, software and sample labeling strategies that can optimize its usefulness in clinical settings.

  15. NMR clinical imaging and spectroscopy: Its impact on nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    1990-02-02

    This is a collection of four papers describing aspects of past and future use of nuclear magnetic resonance as a clinical diagnostic tool. The four papers are entitled (1) What Does NMR Offer that Nuclear Medicine Does Not? by Jerry W. Froelich, (2) Oncological Imaging: Now, Future and Impact Jerry W. Froelich, (3) Magnetic Resonance Spectroscopy/Spectroscopic Imaging and Nuclear Medicine: Past, Present and Future by H. Cecil Charles, and (4) MR Cardiology: Now, Future and Impact by Robert J. Herfkens.

  16. NMR clinical imaging and spectroscopy: Its impact on nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    1990-02-02

    This is a collection of four papers describing aspects of past and future use of nuclear magnetic resonance as a clinical diagnostic tool. The four papers are entitled (1) What Does NMR Offer that Nuclear Medicine Does Not by Jerry W. Froelich, (2) Oncological Imaging: Now, Future and Impact Jerry W. Froelich, (3) Magnetic Resonance Spectroscopy/Spectroscopic Imaging and Nuclear Medicine: Past, Present and Future by H. Cecil Charles, and (4) MR Cardiology: Now, Future and Impact by Robert J. Herfkens.

  17. NMR clinical imaging and spectroscopy: Its impact on nuclear medicine

    International Nuclear Information System (INIS)

    This is a collection of four papers describing aspects of past and future use of nuclear magnetic resonance as a clinical diagnostic tool. The four papers are entitled (1) What Does NMR Offer that Nuclear Medicine Does Not? by Jerry W. Froelich, (2) Oncological Imaging: Now, Future and Impact Jerry W. Froelich, (3) Magnetic Resonance Spectroscopy/Spectroscopic Imaging and Nuclear Medicine: Past, Present and Future by H. Cecil Charles, and (4) MR Cardiology: Now, Future and Impact by Robert J. Herfkens

  18. Imaging retinal ganglion cells: enabling experimental technology for clinical application.

    Science.gov (United States)

    Smith, Corey A; Chauhan, Balwantray C

    2015-01-01

    Recent advances in clinical ophthalmic imaging have enhanced patient care. However, the ability to differentiate retinal neurons, such as retinal ganglion cells (RGCs), would advance many areas within ophthalmology, including the screening and monitoring of glaucoma and other optic neuropathies. Imaging at the single cell level would take diagnostics to the next level. Experimental methods have provided techniques and insight into imaging RGCs, however no method has yet to be translated to clinical application. This review provides an overview of the importance of non-invasive imaging of RGCs and the clinically relevant capabilities. In addition, we report on experimental data from wild-type mice that received an in vivo intravitreal injection of a neuronal tracer that labelled RGCs, which in turn were monitored for up to 100 days post-injection with confocal scanning laser ophthalmoscopy. We were able to demonstrate efficient and consistent RGC labelling with this delivery method and discuss the issue of cell specificity. This type of experimental work is important in progressing towards clinically applicable methods for monitoring loss of RGCs in glaucoma and other optic neuropathies. We discuss the challenges to translating these findings to clinical application and how this method of tracking RGCs in vivo could provide valuable structural and functional information to clinicians. PMID:25448921

  19. Computer-aided diagnosis and artificial intelligence in clinical imaging.

    Science.gov (United States)

    Shiraishi, Junji; Li, Qiang; Appelbaum, Daniel; Doi, Kunio

    2011-11-01

    Computer-aided diagnosis (CAD) is rapidly entering the radiology mainstream. It has already become a part of the routine clinical work for the detection of breast cancer with mammograms. The computer output is used as a "second opinion" in assisting radiologists' image interpretations. The computer algorithm generally consists of several steps that may include image processing, image feature analysis, and data classification via the use of tools such as artificial neural networks (ANN). In this article, we will explore these and other current processes that have come to be referred to as "artificial intelligence." One element of CAD, temporal subtraction, has been applied for enhancing interval changes and for suppressing unchanged structures (eg, normal structures) between 2 successive radiologic images. To reduce misregistration artifacts on the temporal subtraction images, a nonlinear image warping technique for matching the previous image to the current one has been developed. Development of the temporal subtraction method originated with chest radiographs, with the method subsequently being applied to chest computed tomography (CT) and nuclear medicine bone scans. The usefulness of the temporal subtraction method for bone scans was demonstrated by an observer study in which reading times and diagnostic accuracy improved significantly. An additional prospective clinical study verified that the temporal subtraction image could be used as a "second opinion" by radiologists with negligible detrimental effects. ANN was first used in 1990 for computerized differential diagnosis of interstitial lung diseases in CAD. Since then, ANN has been widely used in CAD schemes for the detection and diagnosis of various diseases in different imaging modalities, including the differential diagnosis of lung nodules and interstitial lung diseases in chest radiography, CT, and position emission tomography/CT. It is likely that CAD will be integrated into picture archiving and

  20. In vivo magnetic resonance spectroscopy: basic methodology and clinical applications.

    NARCIS (Netherlands)

    Graaf, M. van der

    2010-01-01

    The clinical use of in vivo magnetic resonance spectroscopy (MRS) has been limited for a long time, mainly due to its low sensitivity. However, with the advent of clinical MR systems with higher magnetic field strengths such as 3 Tesla, the development of better coils, and the design of optimized ra

  1. Non-Invasive Evaluation of the GABAergic/Glutamatergic System in Autistic Patients Observed by MEGA-Editing Proton MR Spectroscopy Using a Clinical 3 Tesla Instrument

    Science.gov (United States)

    Harada, Masafumi; Taki, Masako M.; Nose, Ayumi; Kubo, Hitoshi; Mori, Kenji; Nishitani, Hiromu; Matsuda, Tsuyoshi

    2011-01-01

    Amino acids related to neurotransmitters and the GABAergic/glutamatergic system were measured using a 3 T-MRI instrument in 12 patients with autism and 10 normal controls. All measurements were performed in the frontal lobe (FL) and lenticular nuclei (LN) using a conventional sequence for n-acetyl aspartate (NAA) and glutamate (Glu), and the…

  2. Toward carbon nanotube-based imaging agents for the clinic.

    Science.gov (United States)

    Hernández-Rivera, Mayra; Zaibaq, Nicholas G; Wilson, Lon J

    2016-09-01

    Among the many applications for carbon nanotubes (CNTs), their use in medicine has drawn special attention due to their potential for a variety of therapeutic and diagnostic applications. As progress toward clinical applications continues, monitoring CNTs in vivo will be essential to evaluate their biodistribution, potential toxicity, therapeutic activity, and any physiological changes that the material may induce in specific tissues. There are many different imaging modalities to visualize and track CNTs in vivo, yet only a few are full-body penetrating, a central characteristic that widens their clinical utility. In order to visualize CNTs, chemical modification is often required for the material to be used as a platform to carry imaging agents compatible with one or more of the clinical imaging techniques. Here, we focus on the most recent work involving the use of CNTs as imaging agents for the non-invasive, full-body penetrating clinical modalities of MRI, PET, SPECT, and X-ray CT. The synthesis and modification of the CNT materials are discussed, as well as relevant preclinical studies. PMID:27294540

  3. MR imaging and clinical findings of spontaneous spinal epidural hematoma

    International Nuclear Information System (INIS)

    To describe the MR imaging and clinical findings of spontaneous spinal epidural hematoma. The MR and clinical findings in six patients (M:F=3D4:2;adult:child=3D3:3) with spontaneous spinal epidural hematoma were reviewed. Five patients without any predisposing factor which might cause the condition and one with acute myelogenous leukemia were included. Emergency surgery was performed in two patients, and the other four were managed conservatively. The epidural lesion involved between three and seven vertebrae (mean:4.5), and relative to the spinal cord was located in the posterior-lateral (n=3D4), anterior (n=3D1), or right lateral (n=3D1) area. The hematoma was isointense (n=3D1) or hyperintense (n=3D5) with spinal cord on T1-weighted images, and hypointense (n=3D2) or hyperintense (n=3D4) on T2-weighted images. It was completely absorbed in four of five patients who underwent follow-up MR imaging, but not changed in one. The clinical outcome of these patients was complete recovery (n=3D4), spastic cerebral palsy (n=3D1), or unknown (n=3D1). Because of the lesion's characteristic signal intensity; MR imaging is very useful in the diagnosis and evaluation of spontaneous spinal epidural hematoma. (author)

  4. MR imaging and clinical findings of spontaneous spinal epidural hematoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sam Soo [Seoul City Boramae Hospital, Seoul (Korea, Republic of); Han, Moon Hee; Kim, Hyun Beom [College of Medicine, Seoul National University, Seoul (Korea, Republic of)] [and others

    2000-01-01

    To describe the MR imaging and clinical findings of spontaneous spinal epidural hematoma. The MR and clinical findings in six patients (M:F=3D4:2;adult:child=3D3:3) with spontaneous spinal epidural hematoma were reviewed. Five patients without any predisposing factor which might cause the condition and one with acute myelogenous leukemia were included. Emergency surgery was performed in two patients, and the other four were managed conservatively. The epidural lesion involved between three and seven vertebrae (mean:4.5), and relative to the spinal cord was located in the posterior-lateral (n=3D4), anterior (n=3D1), or right lateral (n=3D1) area. The hematoma was isointense (n=3D1) or hyperintense (n=3D5) with spinal cord on T1-weighted images, and hypointense (n=3D2) or hyperintense (n=3D4) on T2-weighted images. It was completely absorbed in four of five patients who underwent follow-up MR imaging, but not changed in one. The clinical outcome of these patients was complete recovery (n=3D4), spastic cerebral palsy (n=3D1), or unknown (n=3D1). Because of the lesion's characteristic signal intensity; MR imaging is very useful in the diagnosis and evaluation of spontaneous spinal epidural hematoma. (author)

  5. Normal feline brain: clinical anatomy using magnetic resonance imaging.

    Science.gov (United States)

    Mogicato, G; Conchou, F; Layssol-Lamour, C; Raharison, F; Sautet, J

    2012-04-01

    The purpose of this study was to provide a clinical anatomy atlas of the feline brain using magnetic resonance imaging (MRI). Brains of twelve normal cats were imaged using a 1.5 T magnetic resonance unit and an inversion/recovery sequence (T1). Fourteen relevant MRI sections were chosen in transverse, dorsal, median and sagittal planes. Anatomic structures were identified and labelled using anatomical texts and Nomina Anatomica Veterinaria, sectioned specimen heads, and previously published articles. The MRI sections were stained according to the major embryological and anatomical subdivisions of the brain. The relevant anatomical structures seen on MRI will assist clinicians to better understand MR images and to relate this neuro-anatomy to clinical signs.

  6. Dual energy imaging using a clinical on-board imaging system

    International Nuclear Information System (INIS)

    Dual energy (DE) imaging consists of obtaining kilovoltage (kV) x-ray images at two different diagnostic energies and performing a weighted subtraction of these images. A third image is then produced that highlights soft tissue. DE imaging has been used by radiologists to aid in the detection of lung malignancies. However, it has not been used clinically in radiotherapy. The goal of this study is to assess the feasibility of performing DE imaging using a commercial on-board imaging system. Both a simple and an anthropomorphic phantom were constructed for this analysis. Planar kV images of the phantoms were obtained using varied imaging energies and mAs. Software was written to perform DE subtraction using empirically determined weighting factors. Tumor detectability was assessed quantitatively using the signal-difference-to-noise ratio (SDNR). Overall DE subtraction suppressed high density objects in both phantoms. The optimal imaging technique, providing the largest SDNR with a dose less than our reference technique was 140 kVp, 1.0 mAs and 60 kVp, 3.2 mAs. Based on this analysis, DE subtraction imaging is feasible using a commercial on-board imaging system and may improve the visualization of tumors in lung cancer patients undergoing image-guided radiotherapy. (paper)

  7. Chemical Exchange Saturation Transfer MR Imaging Is Superior to Diffusion Tensor Imaging in the Diagnosis and Severity Evaluation of Parkinson's Disease: a Study on Substantia Nigra and Striatum

    Directory of Open Access Journals (Sweden)

    Chunmei eLi

    2015-10-01

    Full Text Available Parkinson’s disease (PD is a neurodegenerative disorder characterized by nigrostriatal cell loss. To date the diagnosis of PD is still based primarily on the clinical manifestations which may be typical and obvious only in advanced-stage PD. Thus, it is crucial to find a reliable marker for the diagnosis of PD. We conducted this study to assess the diagnostic efficiency of chemical-exchange-saturation-transfer (CEST imaging and diffusion-tensor imaging (DTI in PD at 3 Tesla by evaluating changes on substantia nigra and striatum. Twenty-three PD patients and twenty-three age-matched normal controls were recruited. All patients and controls were imaged on a 3 Tesla MR system, using an 8-channel head coil. CEST imaging was acquired in two transverse slices of the head, including substantia nigra and striatum. The magnetization-transfer-ratio asymmetry at 3.5 ppm, MTRasym(3.5ppm, and the total CEST signal intensity between 0 and 4 ppm were calculated. Multi-slice DTI was acquired for all the patients and normal controls. Quantitative analysis was performed on the substantia nigra, globus pallidus, putamen and caudate. The MTRasym(3.5ppm value, the total CEST signal intensity and fractional anisotropy (FA value of the substantia nigra were all significantly lower in PD patients than in normal controls (P = 0.003, P = 0.004 and P < 0.001, respectively. The MTRasym(3.5ppm values of the putamen and the caudate were significantly higher in PD patients than in normal controls (P = 0.010 and P = 0.009, respectively. There were no significant differences for the mean diffusivity (MD in these four regions between PD patients and normal controls. In conclusion, CEST MR imaging provided multiple CEST image contrasts in the substantia nigra and the striatum in PD and may be superior to DTI in the diagnosis of PD.

  8. Lung MRI of invasive fungal infection at 3 Tesla: evaluation of five different pulse sequences and comparison with multidetector computed tomography (MDCT)

    International Nuclear Information System (INIS)

    To evaluate the diagnostic performance of five MR sequences to detect pulmonary infectious lesions in patients with invasive fungal infection (IFI), using multidetector computed tomography (MDCT) as the reference standard. Thirty-four immunocompromised patients with suspected IFI underwent MDCT and MRI. The MR studies were performed using five pulse sequences at 3.0 T: T2-weighted turbo spin echo (TSE), short-tau inversion recovery (STIR), spectrally selective attenuated inversion recovery (SPAIR), T1-weighted high resolution isotropic volume excitation (e-THRIVE) and T1-weighted fast field echo (T1-FFE). The size, lesion-to-lung contrast ratio and the detectability of pulmonary lesions on MR images were assessed. Image quality and artefacts on different sequences were also rated. A total of 84 lesions including nodules (n = 44) and consolidation (n = 40) were present in 75 lobes. SPAIR and e-THRIVE images achieved high overall lesion-related sensitivities for the detection of pulmonary abnormalities (90.5 % and 86.9 %, respectively). STIR showed the highest lesion-to-lung contrast ratio for nodules (21.8) and consolidation (17.0), whereas TSE had the fewest physiological artefacts. MRI at 3.0 T can depict clinically significant pulmonary IFI abnormalities with high accuracy compared to MDCT. SPAIR and e-THRIVE are preferred sequences for the detection of infectious lesions of 5 mm and larger. (orig.)

  9. Lung MRI of invasive fungal infection at 3 Tesla: evaluation of five different pulse sequences and comparison with multidetector computed tomography (MDCT)

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Chenggong; Tan, Xiangliang; Li, Caixia; Wu, Yuankui; Hao, Peng; Xiong, Wei; Xu, Yikai [Southern Medical University, Department of Medical Imaging Center, Nanfang Hospital, Guangzhou, Guangdong (China); Wei, Qi; Feng, Ru; Xu, Jun [Southern Medical University, Department of Hematology, Nanfang Hospital, Guangzhou (China); Chan, Queenie [Philips Healthcare, New Territories (China)

    2014-09-18

    To evaluate the diagnostic performance of five MR sequences to detect pulmonary infectious lesions in patients with invasive fungal infection (IFI), using multidetector computed tomography (MDCT) as the reference standard. Thirty-four immunocompromised patients with suspected IFI underwent MDCT and MRI. The MR studies were performed using five pulse sequences at 3.0 T: T2-weighted turbo spin echo (TSE), short-tau inversion recovery (STIR), spectrally selective attenuated inversion recovery (SPAIR), T1-weighted high resolution isotropic volume excitation (e-THRIVE) and T1-weighted fast field echo (T1-FFE). The size, lesion-to-lung contrast ratio and the detectability of pulmonary lesions on MR images were assessed. Image quality and artefacts on different sequences were also rated. A total of 84 lesions including nodules (n = 44) and consolidation (n = 40) were present in 75 lobes. SPAIR and e-THRIVE images achieved high overall lesion-related sensitivities for the detection of pulmonary abnormalities (90.5 % and 86.9 %, respectively). STIR showed the highest lesion-to-lung contrast ratio for nodules (21.8) and consolidation (17.0), whereas TSE had the fewest physiological artefacts. MRI at 3.0 T can depict clinically significant pulmonary IFI abnormalities with high accuracy compared to MDCT. SPAIR and e-THRIVE are preferred sequences for the detection of infectious lesions of 5 mm and larger. (orig.)

  10. Matching the Clinical Question to the Appropriate Imaging Procedure: What a Cardiologist Wants from Cardiac Imaging

    Directory of Open Access Journals (Sweden)

    S. Wann

    2007-05-01

    Full Text Available In modern medicine, we too often become enamored with technology and lose focus on the reason for per-forming a diagnostic study. Cardiac imaging may have advanced to point of replacing the physical ex-amination, but there is still no substitute for thought-ful planning of a diagnostic approach based on a hier-archy of clinical data, an appreciation of the pre-test likelihood of disease, realistic expectation from vari-ous imaging procedures, and a rational plan for utiliz-ing the information gained. Team work is required to effectively utilize all the capabilities of the modern medical environment. Communication is essential if patients are to receive the best care. As the power and complexity of imag-ing has increase, so has its over-utilization. This lec-ture will focus on maximizing useful diagnostic yield, while minimizing redundancy and excessive costs. While evidence based medical practice is ideally based on controlled randomized trials to show im-proved patient outcomes. Medical imaging has his-torically developed by improving the quality of im-ages, comparing new to existing technologist. Exam-ples will be given of applications of various imaging techniques to common clinical problems, pointing out areas where true evidence is lacking. Appropriate imaging in these situations must be defined by con-sensus of expert opinion. A variety of clinical vi-gnettes will be presented.

  11. Encephale du cheval sain‎ : comparaison coupes anatomiques et images par résonance magnétique haut champ 3 Tesla

    OpenAIRE

    Monteil, Sophie

    2015-01-01

    Aujourd’hui l’Imagerie par Résonance Magnétique (IRM) est la technique d’imagerie de référence pour l’examen du système nerveux central (SNC) chez les humains comme chez les animaux. L’objectif de cette thèse est de proposer un atlas de l’anatomie normale de l’encéphale de cheval adulte sain à l’aide de coupes IRM haute résolution utilisant les relaxations T1 et T2 et de coupes anatomiques. Dans une première partie, les principes physiques à l’origine du signal de résonance magnétique nucléai...

  12. Magnetic resonance imaging for prostate cancer clinical application

    Institute of Scientific and Technical Information of China (English)

    Bing Li; Yong Du; Hanfeng Yang; Yayong Huang; Jun Meng; Dongmei Xiao

    2013-01-01

    As prostate cancer is a biologically heterogeneous disease for which a variety of treatment options are available,the major objective of prostate cancer imaging is to achieve more precise disease characterization.In clinical practice,magnetic resonance imaging (MRI) is one of the imaging tools for the evaluation of prostate cancer,the fusion of MRI or dynamic contrast-enhanced MRI (DCE-MRI) with magnetic resonance spectroscopic imaging (MRSI) is improving the evaluation of cancer location,size,and extent,while providing an indication of tumor aggressiveness.This review summarizes the role of MRI in the application of prostate cancer and describes molecular MRI techniques (including MRSI and DCE-MRI)for aiding prostate cancer management.

  13. Clinical imaging of vascular disease in chronic kidney disease.

    Science.gov (United States)

    Sag, Alan A; Covic, Adrian; London, Gerard; Vervloet, Marc; Goldsmith, David; Gorriz, Jose Luis; Kanbay, Mehmet

    2016-06-01

    Arterial wall calcification, once considered an incidental finding, is now known to be a consistent and strong predictor of cardiovascular events in patients with chronic renal insufficiency. It is also commonly encountered in radiologic examinations as an incidental finding. Forthcoming bench, translational, and clinical data seek to establish this and pre-calcification changes as surrogate imaging biomarkers for noninvasive prognostication and treatment follow-up. Emerging paradigms seek to establish vascular calcification as a surrogate marker of disease. Imaging of pre-calcification and decalcification events may prove more important than imaging of the calcification itself. Data-driven approaches to screening will be necessary to limit radiation exposure and prevent over-utilization of expensive imaging techniques. PMID:26898824

  14. Nuclear Breast Imaging: Clinical Results and Future Directions.

    Science.gov (United States)

    Berg, Wendie A

    2016-02-01

    Interest in nuclear breast imaging is increasing because of technical improvements in dedicated devices that allow the use of relatively low doses of radiotracers with high sensitivity for even small breast cancers. For women with newly diagnosed cancer, primary chemotherapy is often recommended, and improved methods of assessing treatment response are of interest. With widespread breast density notification, functional rather than anatomic methods of screening are of increasing interest as well. For a cancer imaging technology to be adopted, several criteria must be met that will be discussed: evidence of clinical benefit with minimal harm, standardized interpretive criteria, direct biopsy guidance, and acceptable cost-effectiveness.

  15. Clinical task performance and imaging task performance compared for two different commercial electronic portal imaging systems

    International Nuclear Information System (INIS)

    Full text: This paper reports on the investigation and comparison of performance of a Varian Portal Vision system and a Siemens Beamview Plus system using the framework outlined by ICRU Report 54. Radiation Therapy EPI (Electronic Portal Imaging) systems are one of the main applications of digital imaging technology in a radiation therapy department. Radiation Therapy EPI systems may produce images of a lesser quality than the diagnostic radiology equivalent. It is therefore important to optimise the system to obtain the best performance possible. Contrasting opinion on the performance of EPI by clinicians, radiation therapists, medical physicists and engineers often exists, even when the same system and even the same image are being evaluated. Differing opinion occurs because of differences in task end points and task assessment methods of two broad groups of individuals, the human-observer group and the technical-measurement group. Each group uses different task criteria and methodology for assessing performance. The human-observer group is primarily interested in system performance that assures a high level clinical-task performance while the technical-measurement group is concerned with system performance that assures a high level of imaging-task performance. The technical-measurement group tends to be closely associated with imaging system technology, testing, adjustment and optimisation tasks which are couched in terms imaging-task criteria. The human-observer group is usually attempting to optimise performance using clinical-task criteria. The challenge is to provide a balanced evaluation using complementary imaging-task performance and clinical-task performance assessments. Comparison of the systems is on the basis of imaging-task performance i.e. technical-measurement through physical performance assessments such as spatial resolution and noise level, and clinical-task performance i.e. human-observer measurements through the application of psychophysical

  16. Breast imaging with SoftVue: initial clinical evaluation

    Science.gov (United States)

    Duric, Neb; Littrup, Peter; Li, Cuiping; Roy, Olivier; Schmidt, Steven; Cheng, Xiaoyang; Seamans, John; Wallen, Andrea; Bey-Knight, Lisa

    2014-03-01

    We describe the clinical performance of SoftVue, a breast imaging device based on the principles of ultrasound tomography. Participants were enrolled in an IRB-approved study at Wayne State University, Detroit, MI. The main research findings indicate that SoftVue is able to image the whole uncompressed breast up to cup size H. Masses can be imaged in even the densest breasts with the ability to discern margins and mass shapes. Additionally, it is demonstrated that multi-focal disease can also be imaged. The system was also tested in its research mode for additional imaging capabilities. These tests demonstrated the potential for generating tissue stiffness information for the entire breast using through-transmission data. This research capability differentiates SoftVue from the other whole breast systems on the market. It is also shown that MRI-like images can be generated using alternative processing of the echo data. Ongoing research is focused on validating and quantifying these findings in a larger sample of study participants and quantifying SoftVue's ability to differentiate benign masses from cancer.

  17. Unenhanced MR Imaging in adults with clinically suspected acute appendicitis

    DEFF Research Database (Denmark)

    Chabanova, Elizaveta; Balslev, Ingegerd; Achiam, Michael;

    2011-01-01

    PURPOSE: The purpose of the study was to evaluate unenhanced Magnetic Resonance Imaging (MRI) for the diagnosis of appendicitis or another surgery-requiring condition in an adult population scheduled for emergency appendectomy based on a clinical diagnosis of suspected acute appendicitis. MATERIA...... screening before the appendectomy. It may prevent unnecessary surgeries. The fast MRI examination can be adequately performed on an MRI unit of broad range of field strengths...

  18. Clinics in diagnostic imaging (90). Childhood nasopharyngeal carcinoma.

    Science.gov (United States)

    Ng, B K; Chong, C L; Tan, A M; Hwang, W S

    2003-10-01

    An 11-year-old boy presented with a nasopharyngeal mass that was thought to represent a juvenile angiofibroma based on the initial clinical and radiological evaluation. Partial tumour resection was performed. Resected specimen revealed histological diagnosis of undifferentiated carcinoma. Further evaluation of the tumour including MR imaging, radioisotope bone scan, CT thorax and abdomen were performed. Differential diagnoses of childhood nasopharyngeal masses were discussed. The differences between childhood NPC and adult NPC, rhabdomyosarcoma, malignant lymphoma and juvenile nasopharyngeal angiofibroma were also discussed.

  19. Spinal cord ischemia: aetiology, clinical syndromes and imaging features

    Energy Technology Data Exchange (ETDEWEB)

    Weidauer, Stefan [Frankfurt Univ., Sankt Katharinen Hospital Teaching Hospital, Frankfurt am Main (Germany). Dept. of Neurology; Hattingen, Elke; Berkefeld, Joachim [Frankfurt Univ., Frankfurt am Main (Germany). Inst. of Neuroradiology; Nichtweiss, Michael

    2015-03-01

    The purpose of this study was to analyse MR imaging features and lesion patterns as defined by compromised vascular territories, correlating them to different clinical syndromes and aetiological aspects. In a 19.8-year period, clinical records and magnetic resonance imaging (MRI) features of 55 consecutive patients suffering from spinal cord ischemia were evaluated. Aetiologies of infarcts were arteriosclerosis of the aorta and vertebral arteries (23.6 %), aortic surgery or interventional aneurysm repair (11 %) and aortic and vertebral artery dissection (11 %), and in 23.6 %, aetiology remained unclear. Infarcts occurred in 38.2 % at the cervical and thoracic level, respectively, and 49 % of patients suffered from centromedullar syndrome caused by anterior spinal artery ischemia. MRI disclosed hyperintense pencil-like lesion pattern on T2WI in 98.2 %, cord swelling in 40 %, enhancement on post-contrast T1WI in 42.9 % and always hyperintense signal on diffusion-weighted imaging (DWI) when acquired. The most common clinical feature in spinal cord ischemia is a centromedullar syndrome, and in contrast to anterior spinal artery ischemia, infarcts in the posterior spinal artery territory are rare. The exclusively cervical location of the spinal sulcal artery syndrome seems to be a likely consequence of anterior spinal artery duplication which is observed preferentially here. (orig.)

  20. Clinical benefits of diffusion tensor imaging in hydrocephalus.

    Science.gov (United States)

    Ben-Sira, Liat; Goder, Noam; Bassan, Haim; Lifshits, Shlomi; Assaf, Yaniv; Constantini, Shlomi

    2015-08-01

    OBJECT The object of this study was to use diffusion tensor imaging (DTI) to evaluate and characterize white matter changes in hydrocephalus. METHODS The authors performed a retrospective analysis of DTI in a cohort of patients with hydrocephalus (n = 35), 19 of whom had both pre- and postsurgical imaging studies. These patient's DTI values were compared with values extracted from age-dependent trend lines computed from a healthy subject group (n = 70, age span 14 months-14 years). Several DTI parameters in different regions of interest (ROIs) were evaluated to find the most sensitive parameters for clinical decision making in hydrocephalus. RESULTS Compared with healthy controls, patients with active hydrocephalus had a statistically significant change in all DTI parameters. The most sensitive and specific DTI parameter for predicting hydrocephalus was axial diffusivity (λ1) measured at the level of the corona radiata. Diffusion tensor imaging parameters correlated with several conventional radiological parameters in the assessment of hydrocephalus but were not superior to them. There was no convincing correlation between clinical disease severity and DTI parameters. When examining the pre- and postsurgical effect, it was found that DTI may be a sensitive tool for estimating tissue improvement. CONCLUSIONS This large-cohort study with a multidisciplinary approach combining clinical, neurological, radiological, and multiple DTI parameters revealed the most sensitive DTI parameters for identifying hydrocephalus and suggested that they may serve as an important tool for the disorder's quantitative radiological assessment.

  1. Moxifloxacin: Clinically compatible contrast agent for multiphoton imaging

    Science.gov (United States)

    Wang, Taejun; Jang, Won Hyuk; Lee, Seunghun; Yoon, Calvin J.; Lee, Jun Ho; Kim, Bumju; Hwang, Sekyu; Hong, Chun-Pyo; Yoon, Yeoreum; Lee, Gilgu; Le, Viet-Hoan; Bok, Seoyeon; Ahn, G.-One; Lee, Jaewook; Gho, Yong Song; Chung, Euiheon; Kim, Sungjee; Jang, Myoung Ho; Myung, Seung-Jae; Kim, Myoung Joon; So, Peter T. C.; Kim, Ki Hean

    2016-06-01

    Multiphoton microscopy (MPM) is a nonlinear fluorescence microscopic technique widely used for cellular imaging of thick tissues and live animals in biological studies. However, MPM application to human tissues is limited by weak endogenous fluorescence in tissue and cytotoxicity of exogenous probes. Herein, we describe the applications of moxifloxacin, an FDA-approved antibiotic, as a cell-labeling agent for MPM. Moxifloxacin has bright intrinsic multiphoton fluorescence, good tissue penetration and high intracellular concentration. MPM with moxifloxacin was demonstrated in various cell lines, and animal tissues of cornea, skin, small intestine and bladder. Clinical application is promising since imaging based on moxifloxacin labeling could be 10 times faster than imaging based on endogenous fluorescence.

  2. Clinical study of imaging skin cancer margins using polarized light imaging

    Science.gov (United States)

    Samatham, Ravikant; Lee, Ken; Jacques, Steven L.

    2012-02-01

    Skin cancer is most commons type of cancer in United States that occur on sun-exposed cosmetically sensitive areas like face, neck, and forearms. Surgical excision of skin cancer is challenging as more than one-third the actual margins extend beyond the clinically determined margins. Polarized light camera (polCAM) provides images of the superficial layers of the tissue with enhanced contrast which was used to image skin cancer margins. In a NIH-funded pilot study polCAM was used to image skin cancer in patients undergoing Mohs micrographic surgery for skin cancer. Polarized light imaging utilizes the polarization properties of light to create an image of a lesion comprised only of light scattering from the superficial layers of the skin which yields a characteristic "fabric pattern" of the putative lesion and the surrounding normal tissue. In several case studies conducted with a system developed for the clinic, we have found that skin cancer disrupts this fabric pattern, allowing the doctor a new means of identifying the margins of the lesion. Data is acquired before the patient underwent surgery. The clinically determined skin cancer margins were compared with margins determined by examination of the polCAM images. The true margins were provided by the dermatophathologist on examination of the frozen sections. Our initial data suggests that the contrast due to polarization changes associated with cancerous lesions can elucidate margins that were not recognized by the surgeon under normal conditions but were later confirmed by the pathologist.

  3. Imaging and clinical analysis of 12 cases with melioidosis

    International Nuclear Information System (INIS)

    Objective: Imaging and clinical manifestations of melioidosis were analyzed in order to improve our understanding of the disease and to reduce the rate of misdiagnosis. Methods: From 2001 to 2006, 12 melioidosis cases were confirmed by blood, pus and sputum culture. All cases were examined with radiography, and nine of them with CT and 2 with US. The imaging and clinical data were assessed retrospectively. Results: Ten of 12 cases revealed lung abnormalities, the main organ involved by melioidosis in the body. The appearances were observed as follows: diffused sheets and sheets fused partly in bilateral fields of the lungs can be seen on chest radiograph; homogeneous dense shadow of the lobe or segment were observed on plain chest film and CT; blurred strips radiated from hilum were revealed on plain chest film; multitude nodules in 2 lungs showed on CT; cavity with air and liquid be seen on plain chest film and CT; patches and granules in superior and middle fields or (and) inferior fields be seen on plain chest film and CT; arc shadow of water attenuation in dorsal thorax showed on CT. Infections outside the lung can be observed in orbital, lumbar muscle, liver and spleen in 1 case, and thighbone osteomyelitis with multi abscesses in one case. Conclusion: Alhough medioidosis has no characteristic imaging appearances, the disease's location, extent, severity and quantity objectively can be demonstrated by imaging, final confirmation is necessary using the culture of blood, pus and sputum. (authors)

  4. Building blocks for a clinical imaging informatics environment.

    Science.gov (United States)

    Kohli, Marc D; Warnock, Max; Daly, Mark; Toland, Christopher; Meenan, Chris; Nagy, Paul G

    2014-04-01

    Over the past 20 years, imaging informatics has been driven by the widespread adoption of radiology information and picture archiving and communication and speech recognition systems. These three clinical information systems are commonplace and are intuitive to most radiologists as they replicate familiar paper and film workflow. So what is next? There is a surge of innovation in imaging informatics around advanced workflow, search, electronic medical record aggregation, dashboarding, and analytics tools for quality measures (Nance et al., AJR Am J Roentgenol 200:1064-1070, 2013). The challenge lies in not having to rebuild the technological wheel for each of these new applications but instead attempt to share common components through open standards and modern development techniques. The next generation of applications will be built with moving parts that work together to satisfy advanced use cases without replicating databases and without requiring fragile, intense synchronization from clinical systems. The purpose of this paper is to identify building blocks that can position a practice to be able to quickly innovate when addressing clinical, educational, and research-related problems. This paper is the result of identifying common components in the construction of over two dozen clinical informatics projects developed at the University of Maryland Radiology Informatics Research Laboratory. The systems outlined are intended as a mere foundation rather than an exhaustive list of possible extensions.

  5. 'Ready-access' CT imaging for an orthopaedic trauma clinic.

    LENUS (Irish Health Repository)

    Cawley, D

    2011-03-01

    \\'Ready-Access\\' to CT imaging facilities in Orthopaedic Trauma Clinics is not a standard facility. This facility has been available at the regional trauma unit, in Merlin Park Hospital, Galway for the past four years. We reviewed the use of this facility over a 2-year period when 100 patients had CT scans as part of their trauma clinic assessment. The rate of CT scan per clinic was 0.6. The mean waiting time for a CT scan was 30 minutes. 20 (20%) new fractures were confirmed, 33 (33%) fractures were out-ruled, 25 (25%) fractures demonstrated additional information and 8 (8%) had additional fractures. 20 (20%) patients were discharged and 12 (12%) patients were admitted as a result of the CT scan. It adds little time and cost to CT scanning lists.

  6. Clinical value of imaging techniques in childhood osteomyelitis

    International Nuclear Information System (INIS)

    Purpose: The traditional approach to investigating suspected osteomyelitis in children includes conventional radiography and bone scintigraphy. The roles of US, CT and MR imaging are controversial. Our objective was to determine whether the additional use of these modalities would yield information likely to lead to treatment modification. Material and Methods: Sixty-five children with clinically suspected osteomyelitis took part in a prospective study. All patients underwent conventional radiography and bone scintigraphy. In addition to this, US, CT and MR imaging were all performed in 33 patients; the remaining 32 patients were examined with various combinations of these three modalities. The value of the additional information obtained was estimated retrospectively by a pediatric orthopedic surgeon in terms of possible modification of treatment. Results: MR imaging was the modality with the highest sensitivity and specificity for detecting osteomyelitis. MR yielded information likely to influence treatment in the greatest proportion of patients (45%) followed by US (30%). Conclusion: The standard investigation protocol with the addition of US (because of its ability to detect subperiosteal abscesses early and simply) is adequate in uncomplicated cases. When additional imaging is required to outline a lesion, or in complicated cases, and when bone scintigraphy is inconclusive, MR imaging should also be performed. CT should be considered when MR investigation is not available or when anesthesia is required but cannot be provided. (orig.)

  7. Clinical value of imaging techniques in childhood osteomyelitis

    Energy Technology Data Exchange (ETDEWEB)

    Kaiser, S.; Jorulf, H. [Karolinska Hospital, Astrid Lindgren Children`s Hospital, Dept. of Pediatric Radiology, Stockholm (Sweden); Hirsch, G. [Karolinska Hospital, Astrid Lindgren Children`s Hospital, Dept. of Pediatric Surgery, Stockholm (Sweden)

    1998-09-01

    Purpose: The traditional approach to investigating suspected osteomyelitis in children includes conventional radiography and bone scintigraphy. The roles of US, CT and MR imaging are controversial. Our objective was to determine whether the additional use of these modalities would yield information likely to lead to treatment modification. Material and Methods: Sixty-five children with clinically suspected osteomyelitis took part in a prospective study. All patients underwent conventional radiography and bone scintigraphy. In addition to this, US, CT and MR imaging were all performed in 33 patients; the remaining 32 patients were examined with various combinations of these three modalities. The value of the additional information obtained was estimated retrospectively by a pediatric orthopedic surgeon in terms of possible modification of treatment. Results: MR imaging was the modality with the highest sensitivity and specificity for detecting osteomyelitis. MR yielded information likely to influence treatment in the greatest proportion of patients (45%) followed by US (30%). Conclusion: The standard investigation protocol with the addition of US (because of its ability to detect subperiosteal abscesses early and simply) is adequate in uncomplicated cases. When additional imaging is required to outline a lesion, or in complicated cases, and when bone scintigraphy is inconclusive, MR imaging should also be performed. CT should be considered when MR investigation is not available or when anesthesia is required but cannot be provided. (orig.)

  8. The image schema and innate archetypes: theoretical and clinical implications.

    Science.gov (United States)

    Merchant, John

    2016-02-01

    Based in contemporary neuroscience, Jean Knox's 2004 JAP paper 'From archetypes to reflective function' honed her position on image schemas, thereby introducing a model for archetypes which sees them as 'reliably repeated early developmental achievements' and not as genetically inherited, innate psychic structures. The image schema model is used to illustrate how the analyst worked with a patient who began life as an unwanted pregnancy, was adopted at birth and as an adult experienced profound synchronicities, paranormal/telepathic phenomena and visions. The classical approach to such phenomena would see the intense affectivity arising out of a ruptured symbiotic mother-infant relationship constellating certain archetypes which set up the patient's visions. This view is contrasted with Knox's model which sees the archetype an sich as a developmentally produced image schema underpinning the emergence of later imagery. The patient's visions can then be understood to arise from his psychoid body memory related to his traumatic conception and birth. The contemporary neuroscience which supports this view is outlined and a subsequent image schema explanation is presented. Clinically, the case material suggests that a pre-birth perspective needs to be explored in all analytic work. Other implications of Knox's image schema model are summarized. PMID:26785413

  9. Imaging vascular function for early stage clinical trials using dynamic contrast-enhanced magnetic resonance imaging

    International Nuclear Information System (INIS)

    Many therapeutic approaches to cancer affect the tumour vasculature, either indirectly or as a direct target. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has become an important means of investigating this action, both pre-clinically and in early stage clinical trials. For such trials, it is essential that the measurement process (i.e. image acquisition and analysis) can be performed effectively and with consistency among contributing centres. As the technique continues to develop in order to provide potential improvements in sensitivity and physiological relevance, there is considerable scope for between-centre variation in techniques. A workshop was convened by the Imaging Committee of the Experimental Cancer Medicine Centres (ECMC) to review the current status of DCE-MRI and to provide recommendations on how the technique can best be used for early stage trials. This review and the consequent recommendations are summarised here. (orig.)

  10. Imaging vascular function for early stage clinical trials using dynamic contrast-enhanced magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Leach, M.O.; Orton, M. [Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Cancer Research UK and EPSRC Cancer Imaging Centre, Sutton, Surrey (United Kingdom); Morgan, B. [Univ. of Leicester, College of Medicine, Biological Sciences and Psychology, Leicester (United Kingdom); Tofts, P.S. [Brighton and Sussex Medical School, Univ. of Sussex, Clinical Imaging Sciences Centre, Sussex (United Kingdom); Buckley, D.L. [University of Leeds, Division of Medical Physics, Leeds (United Kingdom); Huang, W. [Oregon Health and Science Univ., Advanced Imaging Research Centre, Portland, OR (United States); Horsfield, M.A. [Medical Physics Section, Leicester Royal Infirmary, Dept. of Cardiovascular Sciences, Leicester (United Kingdom); Chenevert, T.L. [Univ. of Michigan Health System, Ann Arbor, MI (United States); Collins, D.J. [Royal Marsden Hospital NHS Foundation Trust, Cancer Research UK and EPSRC Cancer Imaging Centre, Sutton, Surrey (United Kingdom); Jackson, A. [Univ. of Manchester, Wolfson Molecular Imaging Centre, Withington, Manchester, M20 3LJ (United Kingdom); Lomas, D. [Univ. of Cambridge, Dept. of Radiology, Cambridge (United Kingdom); Whitcher, B. [Unit 2 Greenways Business Park, Mango Solutions, Chippenham (United Kingdom); Clarke, L. [Cancer Imaging Program, Imaging Technology Development Branch, Rockville, MD (United States); Plummer, R. [Univ. of Newcastle Upon Tyne, The Medical School, Medical Oncology, Northern Inst. for Cancer Research, Newcastle Upon Tyne (United Kingdom); Judson, I. [Royal Marsden Hospital, Sutton, Surrey (United Kingdom); Jones, R. [Beatson West of Scotland Cancer Centre, Glasgow (United Kingdom); Alonzi, R. [Mount Vernon Cancer Centre, Northwood (United Kingdom); Brunner, T. [Gray Inst. for Radiation, Oncology and Biology, Oxford (United Kingdom); Koh, D.M. [Royal Marsden NHS Foundation Trust, Diagnostic Radiology, Sutton, Surrey (United Kingdom)] [and others

    2012-07-15

    Many therapeutic approaches to cancer affect the tumour vasculature, either indirectly or as a direct target. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has become an important means of investigating this action, both pre-clinically and in early stage clinical trials. For such trials, it is essential that the measurement process (i.e. image acquisition and analysis) can be performed effectively and with consistency among contributing centres. As the technique continues to develop in order to provide potential improvements in sensitivity and physiological relevance, there is considerable scope for between-centre variation in techniques. A workshop was convened by the Imaging Committee of the Experimental Cancer Medicine Centres (ECMC) to review the current status of DCE-MRI and to provide recommendations on how the technique can best be used for early stage trials. This review and the consequent recommendations are summarised here. (orig.)

  11. Noninvasive imaging in acute coronary disease. A clinical perspective

    International Nuclear Information System (INIS)

    Numerous highly complex and sensitive noninvasive imaging techniques have enhanced the care of patients with acute myocardial infarction. Optimum use requires specific objectives to be defined in advance, including a review of the potential impact of the test on subsequent decisions. An additional issue that is subject to scrutiny in the current climate of cost containment relates to the incremental value of a specific examination. The imaging modality to be used will partially depend on other issues, including accessibility, cost, and interindividual or institutional expertise with a particular technique. Major applications in noninvasive imaging in the acute coronary syndromes include the following: (1) diagnosis, including identification of associated diseases and contraindications for acute reperfusion; (2) evaluation and management of complications; (3) determination of prognosis (both early and late); (4) estimation of myocardial viability; (5) assessment of therapeutic efficacy; (6) investigational approaches, including 99mTc-sestamibi tomographic imaging, ultrafast cine computed tomographic scanning, and nuclear magnetic resonance imaging. Previous studies in the prethrombolytic era have documented the powerful impact of radionuclide stress testing on prognosis, but this needs to be reevaluated in the light of the changing current population undergoing stress testing. Preliminary data imply that the prognostic accuracy of stress testing after thrombolytic therapy is diminished. Moreover, the role of the open infarct-related artery in traditional estimates of prognosis requires further study. Noninvasive imaging has multiple applications in the diagnosis and management of patients with acute coronary disease, but the decision to use a specific technology in a particular circumstance mandates good clinical judgment and selectivity. 82 references

  12. Hounsfield unit recovery in clinical cone beam CT images of the thorax acquired for image guided radiation therapy

    Science.gov (United States)

    Slot Thing, Rune; Bernchou, Uffe; Mainegra-Hing, Ernesto; Hansen, Olfred; Brink, Carsten

    2016-08-01

    A comprehensive artefact correction method for clinical cone beam CT (CBCT) images acquired for image guided radiation therapy (IGRT) on a commercial system is presented. The method is demonstrated to reduce artefacts and recover CT-like Hounsfield units (HU) in reconstructed CBCT images of five lung cancer patients. Projection image based artefact corrections of image lag, detector scatter, body scatter and beam hardening are described and applied to CBCT images of five lung cancer patients. Image quality is evaluated through visual appearance of the reconstructed images, HU-correspondence with the planning CT images, and total volume HU error. Artefacts are reduced and CT-like HUs are recovered in the artefact corrected CBCT images. Visual inspection confirms that artefacts are indeed suppressed by the proposed method, and the HU root mean square difference between reconstructed CBCTs and the reference CT images are reduced by 31% when using the artefact corrections compared to the standard clinical CBCT reconstruction. A versatile artefact correction method for clinical CBCT images acquired for IGRT has been developed. HU values are recovered in the corrected CBCT images. The proposed method relies on post processing of clinical projection images, and does not require patient specific optimisation. It is thus a powerful tool for image quality improvement of large numbers of CBCT images.

  13. Left-sided gallbladder: Its clinical significance and imaging presentations

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    AIM: To assess the importance of preoperative diagnosis and presentation of left-sided gallbladder using ultrasound (US), CT and angiography.METHODS: Retrospective review of 1482 patients who underwent enhanced CT scanning was performed. Left-sided gallbladder was diagnosed if a right-sided ligamentum teres was present. The image presentations on US, CT and angiography were also reviewed.RESULTS: Left-sided gallbladder was diagnosed in nine patients. The associated abnormalities on CT imaging included portal vein anomalies, absence of umbilical portion of the portal vein in the left lobe of the liver,club-shaped portal vein in the right lobe of the liver, and difficulty in identifying segment Ⅳ. Angiography in six of nine patients demonstrated abnormal portal venous system (trifurcation type in four of six patients). The main hepatic arteries followed the portal veins in all six patients. The segment Ⅳ artery was identified in four of six patients using angiography, although segment Ⅳ was difficult to define on CT imaging. Hepatectomy was performed in three patients with concomitant liver tumor and the diagnosis of left-sided gallbladder was confirmed intraoperatively.CONCLUSION: Left-sided gallbladder is an important clinical entity in hepatectomy due to its associated portal venous and biliary anomalies. It should be considered in US, CT and angiography images that demonstrate no definite segment IV, absence of umbilical portion of the portal vein in the left lobe, and club-shaped right anterior portal vein.

  14. Functional imaging in oncology. Clinical applications. Vol. 2

    International Nuclear Information System (INIS)

    Easy-to-read manual on new functional imaging techniques in oncology. Explains current clinical applications and outlines future avenues. Includes numerous high-quality illustrations to highlight the major teaching points. In the new era of functional and molecular imaging, both currently available imaging biomarkers and biomarkers under development are expected to lead to major changes in the management of oncological patients. This two-volume book is a practical manual on the various imaging techniques capable of delivering functional information on cancer, including diffusion MRI, perfusion CT and MRI, dual-energy CT, spectroscopy, dynamic contrast-enhanced ultrasonography, PET, and hybrid modalities. This second volume considers the applications and benefits of these techniques in a wide range of tumor types, including their role in diagnosis, prediction of treatment outcome, and early evaluation of treatment response. Each chapter addresses a specific malignancy and is written by one or more acclaimed experts. The lucid text is complemented by numerous high-quality illustrations that highlight key features and major teaching points.

  15. Functional imaging in oncology. Clinical applications. Vol. 2

    Energy Technology Data Exchange (ETDEWEB)

    Luna, Antonio [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Radiology; MRI Health Time Group, Jaen (Spain); Vilanova, Joan C. [Girona Univ. (Spain). Clinica Girona - Hospital Sta. Caterina; Hygino da Cruz, L. Celso Jr. (ed.) [CDPI and IRM, Rio de Janeiro (Brazil). Dept. of Radiology; Rossi, Santiago E. [Centro de Diagnostico, Buenos Aires (Argentina)

    2014-06-01

    Easy-to-read manual on new functional imaging techniques in oncology. Explains current clinical applications and outlines future avenues. Includes numerous high-quality illustrations to highlight the major teaching points. In the new era of functional and molecular imaging, both currently available imaging biomarkers and biomarkers under development are expected to lead to major changes in the management of oncological patients. This two-volume book is a practical manual on the various imaging techniques capable of delivering functional information on cancer, including diffusion MRI, perfusion CT and MRI, dual-energy CT, spectroscopy, dynamic contrast-enhanced ultrasonography, PET, and hybrid modalities. This second volume considers the applications and benefits of these techniques in a wide range of tumor types, including their role in diagnosis, prediction of treatment outcome, and early evaluation of treatment response. Each chapter addresses a specific malignancy and is written by one or more acclaimed experts. The lucid text is complemented by numerous high-quality illustrations that highlight key features and major teaching points.

  16. Clinics in diagnostic imaging (166). Nonketotic hyperglycaemic chorea-hemiballismus.

    Science.gov (United States)

    Goh, Lin Wah; Chinchure, Dinesh; Lim, Tze Chwan

    2016-03-01

    A 68-year-old woman with poorly controlled diabetes mellitus presented to the emergency department with choreoathetoid movements affecting the upper and lower left limbs. Computed tomography of the brain did not show any intracranial abnormalities. However, subsequent magnetic resonance (MR) imaging of the brain revealed an increased T1 signal in the right basal ganglia, raising the suspicion of nonketotic hyperglycaemic chorea-hemiballismus. Management consisted of adjusting her insulin dose to achieve good glycaemic control. The patient subsequently recovered and was discharged after eight days. There are many causes of basal ganglia T1 hyperintensity, including hyperglycaemia in patients with poorly controlled diabetes mellitus. This case emphasises the importance of MR imaging in the early diagnosis of hyperglycaemia as a cause of chorea-hemiballismus, to enable early treatment and a better clinical outcome. PMID:26996977

  17. Clinical and CT imaging features of abdominal fat necrosis

    International Nuclear Information System (INIS)

    Fat necrosis is a common pathological change at abdominal cross-sectional imaging, and it may cause abdominal pain, mimic pathological change of acute abdomen, or be asymptomatic and accompany other pathophysiologic processes. Fat necrosis is actually the result of steatosis by metabolism or mechanical injury. Common processes that are present in fat necrosis include epiploic appendagitis, infarction of the greater omentum, pancreatitis, and fat necrosis related to trauma or ischemia. As a common fat disease, fat necrosis should be known by clinicians and radiologists. Main content of this text is the clinical symptoms and CT findings of belly fat necrosis and related diseases. (authors)

  18. Imaging and clinical characteristics of sporadic Creutzfeldt-Jakob disease

    Directory of Open Access Journals (Sweden)

    HAN Shun-chang

    2013-04-01

    Full Text Available Five patients with sporadic Creutzfeldt-Jakob disease (sCJD presented rapidly progressive dementia which were subacute onset from 1 to 4 months. Among these cases, periodic synchronous discharge (PSD of electroencephalography (EEG was seen in 2 patients. Besides, 4 patients obtained positive results in cerebrospinal fluid (CSF analysis for 14-3-3 protein. The cranial MRI examination showed symmetrical or asymmetrical colored-ribbon-shaped high signals in cerebral cortex or basal ganglia by diffusion weighted imaging (DWI, suggesting that DWI had high sensitivity and specificity for the diagnosis of sCJD as a preferred method in the clinical examination of sCJD.

  19. Evaluation of different imaging chains in clinical chest radiography

    Energy Technology Data Exchange (ETDEWEB)

    Manninen, H.; Terho, E.O.; Wiljasalo, M.; Wiljasalo, S.; Soimakallio, S. (Kuopio Central Hospital (Finland))

    1984-11-01

    Six imaging techniques in clinical chest radiography have been evaluated: four film-screen combinations in the conventional grid technique and two combinations in the air gap technique. Five parameters characterising the quality of a chest radiograph were evaluated by three radiologists and one chest physician by using a nominal grading scale from -2 to +2 compared with the standard technique. The quality parameters judged were: the visibility of peripheral lung vessels, lung parenchyme, the pulmonary hilum, and lung structure behind the heart shadow, as well as the visibility of miscellaneous findings of clinical interest. The air gap technique was shown to be superior to the ordinary grid technique. The diagnostic quality of chest radiography does not necessarily deteriorate with the screen speed. However, statistically significant differences were noticed, even between techniques which had equal speed and physical resolution.

  20. Functional Imaging of Breast Tissue and Clinical Application

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A novel approach to image hemoglobin concentration(ΔDhb) and oxygen saturation (ΔDoxy) of breast tissue is presented. The scenograph of dual-wavelength (760 and 850 nm) near infrared lights through breast tissue is acquired by high sensitive charge coupled device (CCD) camera. The evaluation criterion of the difference of ΔDhb and ΔDoxy between detected and referenced breast tissue can be obtained by a calculation formula without complicate caculation. This approach is applied to clinic detection in breast tissue. The ongoing clinical experiments indicate that malignant tumor usually exhibits characterize of "higher ΔDhb and lower ΔDoxy", while benign lesion often shows "lower ΔDhb and higher ΔDoxy" or other characters. So it is useful to assist the diagnosis of breast disease.

  1. MR imaging assessment of clinical problems in rheumatoid arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Narvaez, Jose A.; Roca, Yolanda; Aguilera, Carlos [Department of CT and MR Imaging, Hospital Duran i Reynals, Universitaria de Bellvitge, Barcelona (Spain); Narvaez, Javier [Department of Medicine, Delfos Medical Center, Barcelona (Spain)

    2002-07-01

    Although MR imaging has been increasingly recognized as a useful tool in the diagnosis of early rheumatoid arthritis (RA) and in the assessment of disease activity, these applications have not yet been usually included in the routine management of this condition. Our goal is to review the current role of MRI in the everyday clinical management of patients with RA. The usefulness of MRI in the evaluation of articular and para-articular changes in specific locations, mainly the craniocervical region and the temporomandibular joint, are reviewed. Clinical problems derived from local extra-articular involvement, such as tenosynovitis, ''rice-bodies'' bursitis, and Baker's cyst rupture, are also described. Finally, we also review the value of MRI in evaluation of some complications of RA such as tendinous rupture, osteonecrosis, stress fracture, and septic arthritis/osteomyelitis. (orig.)

  2. Unenhanced MR Imaging in adults with clinically suspected acute appendicitis

    DEFF Research Database (Denmark)

    Chabanova, Elizaveta; Balslev, Ingegerd; Achiam, Michael;

    2011-01-01

    PURPOSE: The purpose of the study was to evaluate unenhanced Magnetic Resonance Imaging (MRI) for the diagnosis of appendicitis or another surgery-requiring condition in an adult population scheduled for emergency appendectomy based on a clinical diagnosis of suspected acute appendicitis. MATERIALS...... radiologists and one surgeon independent of each other and compared with surgical and pathological records. RESULTS: According to the surgical and histopathological findings 30 of 48 patients (63%) had acute appendicitis. Of the remaining 18 patients, 4 patients had no reasons for the clinical symptoms and 14...... patients had other pathology. For the three reviewers the performance of MRI in the diagnosis of acute appendicitis showed the following sensitivity, specificity and accuracy ranges: 83-93%, 50-83% and 77-83%. Moderate (kappa=0.51) and fair (kappa=0.31) interobserver agreements in the MR diagnosis of acute...

  3. Multimodality imaging in cranial blastomycosis, a great mimicker: Case-based illustration with review of clinical and imaging findings

    Directory of Open Access Journals (Sweden)

    Puneet S Kochar

    2016-01-01

    Full Text Available We describe the clinical, laboratory, and imaging data of three patients who are proven cases of blastomycosis with cranial involvement. In this review, we discuss the imaging features of cranial blastomycosis with relevant clinical case examples including computed tomography (CT, magnetic resonance imaging (MRI, and advanced MR imaging techniques like magnetic resonance spectroscopy (MRS and MR perfusion. Literature is reviewed for modern-day diagnosis and treatment of this fatal intracranial infection, if not diagnosed promptly and managed effectively.

  4. Comparison of clinical and physics scoring of PET images when image reconstruction parameters are varied

    International Nuclear Information System (INIS)

    In this study the quantitative and qualitative image quality (IQ) measurements with clinical judgement of IQ in positron emission tomography (PET) were compared. The limitations of IQ metrics and the proposed criteria of acceptability for PET scanners are discussed. Phantom and patient images were reconstructed using seven different iterative reconstruction protocols. For each reconstructed set of images, IQ was scored based both on the visual analysis and on the quantitative metrics. The quantitative physics metrics did not rank the reconstruction protocols in the same order as the clinicians' scoring of perceived IQ (Rs = -0.54). Better agreement was achieved when comparing the clinical perception of IQ to the physicist's visual assessment of IQ in the phantom images (Rs = +0.59). The closest agreement was seen between the quantitative physics metrics and the measurement of the standard uptake values (SUVs) in small tumours (Rs = +0.92). Given the disparity between the clinical perception of IQ and the physics metrics a cautious approach to use of IQ measurements for determining suspension levels is warranted. (authors)

  5. Sinusitis and intracranial sepsis: the CT imaging and clinical presentation

    International Nuclear Information System (INIS)

    The CT imaging and clinical presentation in 14 children with coexistent intracranial sepsis and sinusitis were reviewed. A routine CT head scan (10-mm thick semi-axial slices through the cranium done before and after intravenous contrast medium administration) was found to be an inadequate initial investigation as the intracranial collection was missed in four patients and the abnormal sinuses not shown in six. In half the children the dagnosis of sinusitis was unsuspected at the time of admission. The dominant clinical features were fever, intense headache and facial swelling in early adolescent males. In this clinical setting we recommend: (1) The routine scan is extended through the frontal and ethmoidal sinuses and photographed at a window level and width showing both bone detail and air/soft tissue interfaces; (2) direct coronal projections are performed through the anterior cranial fossa if no collection is seen on the routine study; (3) an early repeat scan within 48 h if the initial study shows no intracranial pathology but the fronto-ethomoidal sinuses are abnormal and there is a high clinical supicion of intracranial sepsis; and (4) in the presence of intracranial sepsis the vault is viewed at bone window settings to exclude cranial osteomyelitis. (orig.)

  6. Sinusitis and intracranial sepsis: the CT imaging and clinical presentation

    Energy Technology Data Exchange (ETDEWEB)

    Saxton, V.J. [Dept. of Radiology, Royal Children`s Hospital, Melbourne (Australia); Boldt, D.W. [Dept. of Radiology, Royal Children`s Hospital, Melbourne (Australia); Shield, L.K. [Dept. of Neurology, Royal Children`s Hospital, Melbourne (Australia)

    1995-11-01

    The CT imaging and clinical presentation in 14 children with coexistent intracranial sepsis and sinusitis were reviewed. A routine CT head scan (10-mm thick semi-axial slices through the cranium done before and after intravenous contrast medium administration) was found to be an inadequate initial investigation as the intracranial collection was missed in four patients and the abnormal sinuses not shown in six. In half the children the dagnosis of sinusitis was unsuspected at the time of admission. The dominant clinical features were fever, intense headache and facial swelling in early adolescent males. In this clinical setting we recommend: (1) The routine scan is extended through the frontal and ethmoidal sinuses and photographed at a window level and width showing both bone detail and air/soft tissue interfaces; (2) direct coronal projections are performed through the anterior cranial fossa if no collection is seen on the routine study; (3) an early repeat scan within 48 h if the initial study shows no intracranial pathology but the fronto-ethomoidal sinuses are abnormal and there is a high clinical supicion of intracranial sepsis; and (4) in the presence of intracranial sepsis the vault is viewed at bone window settings to exclude cranial osteomyelitis. (orig.)

  7. Correlating Hemodynamic Magnetic Resonance Imaging with high-field Intracranial Vessel Wall Imaging in Stroke

    Science.gov (United States)

    Langdon, Weston; Donahue, Manus J.; van der Kolk, Anja G.; Rane, Swati; Strother, Megan K.

    2014-01-01

    Vessel wall magnetic resonance imaging at ultra-high field (7 Tesla) can be used to visualize vascular lesions noninvasively and holds potential for improving stroke-risk assessment in patients with ischemic cerebrovascular disease. We present the first multi-modal comparison of such high-field vessel wall imaging with more conventional (i) 3 Tesla hemodynamic magnetic resonance imaging and (ii) digital subtraction angiography in a 69-year-old male with a left temporal ischemic infarct. PMID:25426229

  8. Correlating Hemodynamic Magnetic Resonance Imaging with high-field Intracranial Vessel Wall Imaging in Stroke

    OpenAIRE

    Langdon, Weston; Donahue, Manus J.; van der Kolk, Anja G.; Rane, Swati; Strother, Megan K.

    2014-01-01

    Vessel wall magnetic resonance imaging at ultra-high field (7 Tesla) can be used to visualize vascular lesions noninvasively and holds potential for improving stroke-risk assessment in patients with ischemic cerebrovascular disease. We present the first multi-modal comparison of such high-field vessel wall imaging with more conventional (i) 3 Tesla hemodynamic magnetic resonance imaging and (ii) digital subtraction angiography in a 69-year-old male with a left temporal ischemic infarct.

  9. Stress fractures: pathophysiology, clinical presentation, imaging features, and treatment options.

    Science.gov (United States)

    Matcuk, George R; Mahanty, Scott R; Skalski, Matthew R; Patel, Dakshesh B; White, Eric A; Gottsegen, Christopher J

    2016-08-01

    Stress fracture, in its most inclusive description, includes both fatigue and insufficiency fracture. Fatigue fractures, sometimes equated with the term "stress fractures," are most common in runners and other athletes and typically occur in the lower extremities. These fractures are the result of abnormal, cyclical loading on normal bone leading to local cortical resorption and fracture. Insufficiency fractures are common in elderly populations, secondary to osteoporosis, and are typically located in and around the pelvis. They are a result of normal or traumatic loading on abnormal bone. Subchondral insufficiency fractures of the hip or knee may cause acute pain that may present in the emergency setting. Medial tibial stress syndrome is a type of stress injury of the tibia related to activity and is a clinical syndrome encompassing a range of injuries from stress edema to frank-displaced fracture. Atypical subtrochanteric femoral fracture associated with long-term bisphosphonate therapy is also a recently discovered entity that needs early recognition to prevent progression to a complete fracture. Imaging recommendations for evaluation of stress fractures include initial plain radiographs followed, if necessary, by magnetic resonance imaging (MRI), which is preferred over computed tomography (CT) and bone scintigraphy. Radiographs are the first-line modality and may reveal linear sclerosis and periosteal reaction prior to the development of a frank fracture. MRI is highly sensitive with findings ranging from periosteal edema to bone marrow and intracortical signal abnormality. Additionally, a brief description of relevant clinical management of stress fractures is included. PMID:27002328

  10. Clinical applications of cobalt-radionuclides in neuro-imaging

    International Nuclear Information System (INIS)

    The aim of the studies embodied in this thesis was to investigate the clinical applicability of Co in euro-imaging using positron emission tomography (PET). To this purpose, a set of closely related pilot studies were performed in patients suffering from several neurological diseases affecting the brain. Chapter 2 discusses the physiological role of Co and both indications and complications of Co-administration in the past. The probable deposition mechanism of Co is described, potential (absence of) evidence of Co mimicking Ca in vivo is discussed, a comparison is made with other tracer-analogues (Ga, TI, Rb) and several hypotheses with respect to the pharmacokinetic behaviour of Co and the role of (inflammatory) proteins and cells are forwarded. The etiologic mechanism(s), clinical symptoms, Ca-related pathophysiology and (most recent) imaging techniques are reviewed of Multiple Sclerosis, cerebrovascular stroke, traumatic brain injury and primary brain tumours. The major goal of these respective reviews is both a rough outline of present insights and near-future developments and an assessment of the (im)possibilities in visualising the actual substrate of disease. Since Co is assumed to reflect (the common pathway of) Ca, an application of Co (based on cell-decay and inflammation) may be hypothesised in all of the diseases mentioned. These considerations served as a theoretical basis for our further studies in clinical practice. Chapter 3 (Original reprints) presents the actual results, whil Chapter 4 (General discussion) reflects on lessons that can be learned from the present work and consequently formulates some suggestions for future (extended) studies. The contours of possible new emerging areas of interest (dementia of the Alzheimer type; vascular dementia; stunned myocardium) are drawn in continuation of the foregoing studies. 47 refs

  11. Clinical applications of cobalt-radionuclides in neuro-imaging

    Energy Technology Data Exchange (ETDEWEB)

    Jansen, H.M.L

    1998-04-01

    The aim of the studies embodied in this thesis was to investigate the clinical applicability of Co in euro-imaging using positron emission tomography (PET). To this purpose, a set of closely related pilot studies were performed in patients suffering from several neurological diseases affecting the brain. Chapter 2 discusses the physiological role of Co and both indications and complications of Co-administration in the past. The probable deposition mechanism of Co is described, potential (absence of) evidence of Co mimicking Ca in vivo is discussed, a comparison is made with other tracer-analogues (Ga, TI, Rb) and several hypotheses with respect to the pharmacokinetic behaviour of Co and the role of (inflammatory) proteins and cells are forwarded. The etiologic mechanism(s), clinical symptoms, Ca-related pathophysiology and (most recent) imaging techniques are reviewed of Multiple Sclerosis, cerebrovascular stroke, traumatic brain injury and primary brain tumours. The major goal of these respective reviews is both a rough outline of present insights and near-future developments and an assessment of the (im)possibilities in visualising the actual substrate of disease. Since Co is assumed to reflect (the common pathway of) Ca, an application of Co (based on cell-decay and inflammation) may be hypothesised in all of the diseases mentioned. These considerations served as a theoretical basis for our further studies in clinical practice. Chapter 3 (Original reprints) presents the actual results, whil Chapter 4 (General discussion) reflects on lessons that can be learned from the present work and consequently formulates some suggestions for future (extended) studies. The contours of possible new emerging areas of interest (dementia of the Alzheimer type; vascular dementia; stunned myocardium) are drawn in continuation of the foregoing studies. 47 refs.

  12. Advances in functional magnetic resonance imaging: technology and clinical applications.

    Science.gov (United States)

    Dickerson, Bradford C

    2007-07-01

    Functional MRI (fMRI) is a valuable method for use by clinical investigators to study task-related brain activation in patients with neurological or neuropsychiatric illness. Despite the relative infancy of the field, the rapid adoption of this functional neuroimaging technology has resulted from, among other factors, its ready availability, its relatively high spatial and temporal resolution, and its safety as a noninvasive imaging tool that enables multiple repeated scans over the course of a longitudinal study, and thus may lend itself well as a measure in clinical drug trials. Investigators have used fMRI to identify abnormal functional brain activity during task performance in a variety of patient populations, including those with neurodegenerative, demyelinating, cerebrovascular, and other neurological disorders that highlight the potential utility of fMRI in both basic and clinical spheres of research. In addition, fMRI studies reveal processes related to neuroplasticity, including compensatory hyperactivation, which may be a universally-occurring, adaptive neural response to insult. Functional MRI is being used to study the modulatory effects of genetic risk factors for neurological disease on brain activation; it is being applied to differential diagnosis, as a predictive biomarker of disease course, and as a means to identify neural correlates of neurotherapeutic interventions. Technological advances are rapidly occurring that should provide new applications for fMRI, including improved spatial resolution, which promises to reveal novel insights into the function of fine-scale neural circuitry of the human brain in health and disease.

  13. Clinical application of functional magnetic resonance imaging in China

    Institute of Scientific and Technical Information of China (English)

    MA Lin

    2006-01-01

    @@ Functional magnetic resonance imaging (fMRI)has been widely used in basic research in the past decade, and more clinically in recent years.Unlike conventional MRI that demonstrates the anatomy and morphology of the brain, fMRI provides the functional information of the brain, including neuronal activation, perfusion, diffusion, metabolism,and fiber connection. Since the publication of the pioneer study by Ogawa et al1 in 1990, blood oxygenation level dependent (BOLD) technique has been adopted by neuroscientists and psychologists in research into the mechanisms of motion, vision,hearing, language, memory, and functions of the brain. Soon after, clinical studies with BOLD technique were conducted in some fields like surgery (surgical planning). In China, however, basic and clinical studies on fMRI in the early years were limited by the shortage of funding, difficulty in integrating personnel of different disciplines from different institutions, and long-term use of MR scanners. In recent years, the studies on fMRI in this country have been flourishing as the conditions are greatly improved, and the number of published papers has increased because more and more radiologists and clinicians are involved.

  14. Hemicrania Continua: Functional Imaging and Clinical Features With Diagnostic Implications.

    Science.gov (United States)

    Sahler, Kristen

    2013-04-10

    This review focuses on summarizing 2 pivotal articles in the clinical and pathophysiologic understanding of hemicrania continua (HC). The first article, a functional imaging project, identifies both the dorsal rostral pons (a region associated with the generation of migraines) and the posterior hypothalamus (a region associated with the generation of cluster and short-lasting unilateral neuralgiform headache with conjunctival injection and tearing [SUNCT]) as active during HC. The second article is a summary of the clinical features seen in a prospective cohort of HC patients that carry significant diagnostic implications. In particular, they identify a wider range of autonomic signs than what is currently included in the International Headache Society criteria (including an absence of autonomic signs in a small percentage of patients), a high frequency of migrainous features, and the presence of aggravation and/or restlessness during attacks. Wide variations in exacerbation length, frequency, pain description, and pain location (including side-switching pain) are also noted. Thus, a case is made for widening and modifying the clinical diagnostic criteria used to identify patients with HC.

  15. Clinical, FDG and amyloid PET imaging in posterior cortical atrophy.

    Science.gov (United States)

    Singh, Tarun D; Josephs, Keith A; Machulda, Mary M; Drubach, Daniel A; Apostolova, Liana G; Lowe, Val J; Whitwell, Jennifer L

    2015-06-01

    The purpose of this study was to identify the clinical, [(18)F]-fluorodeoxyglucose positron emission tomography (FDG-PET) and amyloid-PET findings in a large cohort of posterior cortical atrophy (PCA) patients, to examine the neural correlates of the classic features of PCA, and to better understand the features associated with early PCA. We prospectively recruited 25 patients who presented to the Mayo Clinic between March 2013 and August 2014 and met diagnostic criteria for PCA. All patients underwent a standardized set of tests and amyloid imaging with [(11)C] Pittsburg compound B (PiB). Seventeen (68 %) underwent FDG-PET scanning. We divided the cohort at the median disease duration of 4 years in order to assess clinical and FDG-PET correlates of early PCA (n = 13). The most common clinical features were simultanagnosia (92 %), dysgraphia (68 %), poly-mini-myoclonus (64 %) and oculomotor apraxia (56.5 %). On FDG-PET, hypometabolism was observed bilaterally in the lateral and medial parietal and occipital lobes. Simultanagnosia was associated with hypometabolism in the right occipital lobe and posterior cingulum, optic ataxia with hypometabolism in left occipital lobe, and oculomotor apraxia with hypometabolism in the left parietal lobe and posterior cingulate gyrus. All 25 PCA patients were amyloid positive. Simultanagnosia was the only feature present in 85 % of early PCA patients. The syndrome of PCA is associated with posterior hemisphere hypometabolism and with amyloid deposition. Many of the classic features of PCA show associated focal, but not widespread, areas of involvement of these posterior hemispheric regions. Simultanagnosia appears to be the most common and hence sensitive feature of early PCA. PMID:25862483

  16. Cryogenic phased-array for high resolution magnetic resonance imaging (MRI); assessment of clinical and research applications

    Science.gov (United States)

    Ip, Flora S.

    Magnetic Resonance (MR) imaging is one of the most powerful tools in diagnostic medicine for soft tissue imaging. Image acquisition techniques and hardware receivers are very important in achieving high contrast and high resolution MR images. An aim of this dissertation is to design single and multi-element room and cryogenic temperature arrays and make assessments of their signal-to-noise ratio (SNR) and SNR gain. In this dissertation, four sets of MR receiver coils are built. They are the receiver-only cryo-coils that are not commercially available. A tuning and matching circuit is attached to each coil. The tuning and matching circuits are simple; however, each device component has to operate at a high magnetic field and cryogenic temperature environment. Remote DC bias of the varactor controls the tuning and matching outside the scanner room. Active detuning of the resonator is done by two p-i-n junction (PIN) diodes. Cooling of the receiver is done by a customized liquid nitrogen cryostat. The first application is to build a 3-Tesla 2x1 horseshoe counter-rotating current (CRC) cryogenic array to image the tibia in a human body. With significant increase in SNR, the surface coil should deliver high contrast and resolution images that can show the trabecular bone and bone marrow structure. This structural image will be used to model the mechanical strength of the bone as well as bone density and chance of fracture. The planar CRC is a unique design of this surface array. The second application is to modify the coil design to 7-Tesla to study the growth of infant rhesus monkey eyes. Fast scan MR images of the infant monkey heads are taken for monitoring shapes of their eyeballs. The monkeys are induced with shortsightedness by eye lenses, and they are scanned periodically to get images of their eyeballs. The field-of-view (FOV) of these images is about five centimeters and the area of interest is two centimeters deep from the surface. Because of these reasons

  17. Fat saturation in dynamic breast MRI at 3 Tesla: is the Dixon technique superior to spectral fat saturation? A visual grading characteristics study

    International Nuclear Information System (INIS)

    To intra-individually compare the diagnostic image quality of Dixon and spectral fat suppression at 3 T. Fifty consecutive patients (mean age 55.1 years) undergoing 3 T breast MRI were recruited for this prospective study. The image protocol included pre-contrast and delayed post-contrast spectral and Dixon fat-suppressed T1w series. Two independent blinded readers compared spectral and Dixon fat-suppressed series by evaluating six ordinal (1 worst to 5 best) image quality criteria (image quality, delineation of anatomical structures, fat suppression in the breast and axilla, lesion delineation and internal enhancement). Breast density and size were assessed. Data analysis included Spearman's rank correlation coefficient and visual grading characteristics (VGC) analysis. Four examinations were excluded; 48 examinations in 46 patients were evaluated. In VGC analysis, the Dixon technique was superior regarding image quality criteria analysed (P < 0.01). Smaller breast size and lower breast density were significantly (P < 0.01) correlated with impaired spectral fat suppression quality. No such correlation was identified for the Dixon technique, which showed reconstruction-based water-fat mixups leading to insufficient image quality in 20.8 %. The Dixon technique outperformed spectral fat suppression in all evaluated criteria (P < 0.01). Non-diagnostic examinations can be avoided by fat and water image reconstruction. The superior image quality of the Dixon technique can improve breast MRI interpretation. (orig.)

  18. Fat saturation in dynamic breast MRI at 3 Tesla: is the Dixon technique superior to spectral fat saturation? A visual grading characteristics study

    Energy Technology Data Exchange (ETDEWEB)

    Clauser, P. [University of Udine, Azienda Ospedaliero-Universitaria ' ' S.Maria della Misericordia' ' , Institute of Diagnostic Radiology, Udine (Italy); Medical University of Vienna, Department of Biomedical Imaging and Image-guided interventions, Division of Molecular and Gender Imaging, Vienna (Austria); Pinker, K.; Helbich, T.H.; Kapetas, P.; Bernathova, M.; Baltzer, P.A.T. [Medical University of Vienna, Department of Biomedical Imaging and Image-guided interventions, Division of Molecular and Gender Imaging, Vienna (Austria)

    2014-09-15

    To intra-individually compare the diagnostic image quality of Dixon and spectral fat suppression at 3 T. Fifty consecutive patients (mean age 55.1 years) undergoing 3 T breast MRI were recruited for this prospective study. The image protocol included pre-contrast and delayed post-contrast spectral and Dixon fat-suppressed T1w series. Two independent blinded readers compared spectral and Dixon fat-suppressed series by evaluating six ordinal (1 worst to 5 best) image quality criteria (image quality, delineation of anatomical structures, fat suppression in the breast and axilla, lesion delineation and internal enhancement). Breast density and size were assessed. Data analysis included Spearman's rank correlation coefficient and visual grading characteristics (VGC) analysis. Four examinations were excluded; 48 examinations in 46 patients were evaluated. In VGC analysis, the Dixon technique was superior regarding image quality criteria analysed (P < 0.01). Smaller breast size and lower breast density were significantly (P < 0.01) correlated with impaired spectral fat suppression quality. No such correlation was identified for the Dixon technique, which showed reconstruction-based water-fat mixups leading to insufficient image quality in 20.8 %. The Dixon technique outperformed spectral fat suppression in all evaluated criteria (P < 0.01). Non-diagnostic examinations can be avoided by fat and water image reconstruction. The superior image quality of the Dixon technique can improve breast MRI interpretation. (orig.)

  19. Influence on flux density of intraoral dental magnets during 1.5 and 3.0 Tesla MRI; Beeinflussung der Flussdichte intraoraler Dentalmagnete im 1,5 und 3 Tesla-MRT

    Energy Technology Data Exchange (ETDEWEB)

    Blankenstein, F.H.; Peroz, I. [Charite, Berlin (Germany). Charite Centrum 3 - Zahn-, Mund- und Kieferheilkunde; Truong, B. [Zahnarztpraxis Berlin (Germany); Thomas, A. [Charite, Berlin (Germany). Charite Centrum 6 - Diagnostische und Interventionelle Radiologie und Nuklearmedizin; Boeckler, A. [Halle-Wittenberg Univ. (Germany). Zentrum fuer Zahn-, Mund- und Kieferheilkunde

    2011-08-15

    Purpose: When using dental duo-magnet systems, a mini-magnet remains in the jaw after removal of the prosthesis. In some cases, implant-borne magnets may be removed, whereas tooth-borne magnets are irreversibly fixed on a natural tooth root. The goal of this paper is to identify the impacts of the duration and orientation of exposure on these magnets in a 1.5 or 3 Tesla MRI. Materials and Methods: For this study, 30 SmCo and 60 NdFeB magnets were used. During the first experiment, they were exposed with free orientation for 64 minutes. During the second experiment, the magnets were fixed in position and exposed at 1.5 and 3 Tesla while aligned in a parallel or antiparallel direction. Results: While the duration of exposure in MRI is irrelevant, the orientation is not. The coercive field strength of these NdFeB and SmCo alloys is not sufficient to reliably withstand demagnetization in a 1.5 or 3 T MRI when aligned in an antiparallel direction. At 1.5 T neodymium magnets were reduced to approx. 34 % and samarium magnets to approx. 92 % of their initial values. At 3 T all magnets were reversed. Conclusion: As a precaution, the worst-case scenario, i.e. an antiparallel orientation, should be assumed when using a duo-magnet system. If an MRI can be postponed, the general dentist should remove implant-borne magnets. If there is a vital indication, irreversible damage to the magnets is acceptable in consultation with the patient since the replacement costs are irrelevant given the underlying disease. (orig.)

  20. Lumbar spinal imaging in radicular pain and related conditions. Understanding diagnostic images in a clinical context

    Energy Technology Data Exchange (ETDEWEB)

    Wilmink, Jan T. [University Hospital Maastricht (Netherlands). Dept. Radiology

    2010-07-01

    There is general agreement that lumbosacral nerve root compression is a prime factor in the pathogenesis of sciatica and neurogenic claudication, although humoral and vascular factors certainly play a role as well. This book focuses on imaging of the various ways in which nerve root compression can come about, and assessing which anatomic features are reliably associated with the occurrence of radicular pain, as opposed to morphologic findings which are probably coincidental. After a discussion of the nature of radicular pain and related symptoms, spinal imaging techniques and options are reviewed, with emphasis on the role of MR myelography in assessing the condition of the intradural nerve roots. A chapter on normal topographic, sectional, and functional (dynamic) radiologic anatomy is followed by a presentation on pathologic anatomy, addressing the various mechanisms of nerve root compression. In the chapter on pre- and postoperative imaging, features which may help to predict the evolution of the symptoms are discussed, with an eye to selecting candidates for surgical treatment. This is followed by a discussion of the role and limitations of imaging studies in various adverse postoperative conditions. In illustrations involving patient studies, imaging features are linked where possible to the clinical symptoms and history of the individuals involved. (orig.)

  1. Hounsfield unit recovery in clinical cone beam CT images of the thorax acquired for image guided radiation therapy

    DEFF Research Database (Denmark)

    Thing, Rune Slot; Bernchou, Uffe; Mainegra-Hing, Ernesto;

    2016-01-01

    A comprehensive artefact correction method for clinical cone beam CT (CBCT) images acquired for image guided radiation therapy (IGRT) on a commercial system is presented. The method is demonstrated to reduce artefacts and recover CT-like Hounsfield units (HU) in reconstructed CBCT images of five...

  2. Juvenile idiopathic arthritis: clinically relevant imaging in diagnosis and monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Southwood, Tauny [Birmingham Children' s Hospital NHS Foundation Trust, Department of Rheumatology, Birmingham (United Kingdom)

    2008-06-15

    The role of plain radiographs in monitoring the disease process in JIA is being increasingly superseded by MRI. The use of ultrasound by clinicians is contentious, but has the potential to corroborate and supplement the clinical impression of individual joint inflammation and it can be very useful for localising intra-articular treatment at the bedside. There are exciting developments in MRS technology which may eventually allow in vivo evaluation of the acute inflammatory process, measurement of early responses to treatment and detection of residual inflammation. The aim of this article is to describe a clinician's view of the current role of imaging in the diagnosis and monitoring of JIA. (orig.)

  3. SLAP lesions: Anatomy, clinical presentation, MR imaging diagnosis and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Debra [University of California San Diego, Department of Radiology, 200 W. Arbor Drive, San Diego, CA 92103 (United States); VA Healthcare System San Diego, Department of Radiology, 3350 La Jolla Village Drive, La Jolla, CA 92161 (United States); MedRay Imaging and Fraser Health Authority, Vancouver, BC (Canada)], E-mail: cbchung@ucsd.edu; Mohana-Borges, Aurea; Borso, Maya; Chung, Christine B. [University of California San Diego, Department of Radiology, 200 W. Arbor Drive, San Diego, CA 92103 (United States); VA Healthcare System San Diego, Department of Radiology, 3350 La Jolla Village Drive, La Jolla, CA 92161 (United States)

    2008-10-15

    ABSTRACT: Superior labral anterior posterior (SLAP) tears are an abnormality of the superior labrum usually centered on the attachment of the long head of the biceps tendon. Tears are commonly caused by repetitive overhead motion or fall on an outstretched arm. SLAP lesions can lead to shoulder pain and instability. Clinical diagnosis is difficult thus imaging plays a key diagnostic role. The normal anatomic variability of the capsulolabral complex can make SLAP lesions a diagnostic challenge. Concurrent shoulder injuries are often present including rotator cuff tears, cystic changes or marrow edema in the humeral head, capsular laxity, Hill-Sachs or Bankart lesion. The relevant anatomy, capsulolabral anatomic variants, primary and secondary findings of SLAP tears including MR arthrography findings, types of SLAP lesions and a practical approach to labral lesions are reviewed.

  4. Clinical and imaging features of neonatal chlamydial pneumonia

    International Nuclear Information System (INIS)

    Objective: To study the clinical and imaging features of chlamydial pneumonia in newborns. Methods: Medical records,chest X-Ray and CT findings of 17 neonates with chlamydia pneumonia were reviewed. The age was ranged from 9.0 to 28.0 days with mean of (16.8 ± 5.8) days. There were 11 males and 6 females. Sixteen were full term infants and one was born post term. All babies were examined with chest X-ray film, and 13 patients also underwent chest CT scan. Serologic test using immunofluorescence method for Chlamydia IgG and IgM antibodies were performed in all patients. Results: All newborns presented with cough but without fever. Positive results of the serologic tests were demonstrated. Chest films showed bilateral hyperventilation in 10 patients, diffuse reticular nodules in 10 patients including nodules mimicking military tuberculosis in 7 patients, and accompanying consolidation in 9 patients. CT features included interstitial reticular nodules in 13 patients with size, density, and distribution varied. Subpleural nodules (11 patients) and fusion of nodules (10 patients) predominated. Bilateral hyperinflation was found in 10 patients, which combined with infiltration in 12 patients, thickening of bronchovascular bundles in 10 patients, and ground glass sign in 5 patients. No pleural effusion and lymphadenopathy was detected in any patient. Conclusions: Bilateral hyperinflation and diffuse interstitial reticular nodules were the most common imaging features of neonatal chlamydial pneumonia. The main clinical characteristic of neonatal chlamydial pneumonia is respiratory symptoms without fever, which is helpful to its diagnosis. (authors)

  5. Imaging tissue hypoxia: clinical and pre-clinical experience with {sup 123}IAZA

    Energy Technology Data Exchange (ETDEWEB)

    Wiebe, L.I. [University of Alberta, Edmonton (Canada). Noujaim Institute for Pharmaceutical Oncology Research, Faculty of Pharmacy and Pharmaceutical Sciences

    1997-10-01

    The molecular mechanisms that underline the selective binding of iodazomycin arabinoside, IAZA, and related nitromidazoles are reviewed as a basis for interpretation of preclinical and clinical data for hypoxic binding of radioiodinated IAZA. Clinical data are presented for {sup 123}IAZA uptake in a number of pathologies including metastatic tumours, peripheral vascular disease in diabetes, muscle stress and rheumatoid arthritis. The results of studies to determine the influence of tumour type on uptake of {sup 123} I-IAZA in patients with a variety of deep-seated solid tumours will be presented. Correlations of hypoxia-dependent binding with {sup 99m}Tc-HMPAO perfusion images will be reviewed and early correlations of uptake to treatment response in cancer will be presented. Unusual features of {sup 123}I-IAZA biodistribution will also be discussed together with detailed pharmacokinetic and radiation dosimetry data for `2{sup 123}I- IAZA in normal volunteers 27 refs., 1 fig.

  6. Imaging tissue hypoxia: clinical and pre-clinical experience with 123IAZA

    International Nuclear Information System (INIS)

    The molecular mechanisms that underline the selective binding of iodazomycin arabinoside, IAZA, and related nitromidazoles are reviewed as a basis for interpretation of preclinical and clinical data for hypoxic binding of radioiodinated IAZA. Clinical data are presented for 123IAZA uptake in a number of pathologies including metastatic tumours, peripheral vascular disease in diabetes, muscle stress and rheumatoid arthritis. The results of studies to determine the influence of tumour type on uptake of 123 I-IAZA in patients with a variety of deep-seated solid tumours will be presented. Correlations of hypoxia-dependent binding with 99mTc-HMPAO perfusion images will be reviewed and early correlations of uptake to treatment response in cancer will be presented. Unusual features of 123I-IAZA biodistribution will also be discussed together with detailed pharmacokinetic and radiation dosimetry data for '2123I- IAZA in normal volunteers

  7. Cerebellar disorders: clinical/radiologic findings and modern imaging tools.

    Science.gov (United States)

    Manto, Mario; Habas, Christophe

    2016-01-01

    Cerebellar disorders, also called cerebellar ataxias, comprise a large group of sporadic and genetic diseases. Their core clinical features include impaired control of coordination and gait, as well as cognitive/behavioral deficits usually not detectable by a standard neurologic examination and therefore often overlooked. Two forms of cognitive/behavioral syndromes are now well identified: (1) the cerebellar cognitive affective syndrome, which combines an impairment of executive functions, including planning and working memory, deficits in visuospatial skills, linguistic deficiencies such as agrammatism, and inappropriate behavior; and (2) the posterior fossa syndrome, a very acute form of cerebellar cognitive affective syndrome occurring essentially in children. Sporadic ataxias include stroke, toxic causes, immune ataxias, infectious/parainfectious ataxias, traumatic causes, neoplasias and paraneoplastic syndromes, endocrine disorders affecting the cerebellum, and the so-called "degenerative ataxias" (multiple system atrophy, and sporadic adult-onset ataxias). Genetic ataxias include mainly four groups of disorders: autosomal-recessive cerebellar ataxias, autosomal-dominant ataxias (spinocerebellar ataxias and episodic ataxias), mitochondrial disorders, and X-linked ataxias. In addition to biochemical studies and genetic tests, brain imaging techniques are a cornerstone for the diagnosis, clinicoanatomic correlations, and follow-up of cerebellar ataxias. Modern radiologic tools to assess cerebellar ataxias include: functional imaging studies, magnetic resonance spectroscopy, volumetric studies, and tractography. These complementary methods provide a multimodal appreciation of the whole long-range cerebellar network functioning, and allow the extraction of potential biomarkers for prognosis and rating level of recovery after treatment. PMID:27432679

  8. Clinical imaging centers: The role of state radiation control programs

    International Nuclear Information System (INIS)

    Radiation Protection is mandated in all 50 states. Regulatory control over naturally occurring and accelerator produced radioactive materials use is exclusively by state government. Although states are independent bodies there are many similarities in their regulatory approaches. Differences in the degree of regulatory control are minimized through use of the Suggested State Regulations for the Control of Radiation and other guidance documents provided by the Conference of Radiation Control Program Directors, Inc. This paper discusses the general requirements to obtain a license and/or registration to produce radioactive material in an accelerator, prepare an imaging agent and/or operate an imaging clinic. These requirements include minimum standards for training and experience of all principal users, equipment specifications, facilities design and construction, specific operating and emergency procedures, radiation protection surveys and monitoring of personnel exposures, ongoing training of staff, and a commitment to ALARA (the philosophy of keeping radiation exposures as low as reasonably achievable). The nature and frequency of routine inspections to ensure adequate protection of workers and the public is also covered

  9. Fast isotropic banding-free bSSFP imaging using 3D dynamically phase-cycled radial bSSFP (3D DYPR-SSFP)

    Energy Technology Data Exchange (ETDEWEB)

    Benkert, Thomas; Blaimer, Martin; Breuer, Felix A. [Research Center Magnetic Resonance Bavaria (MRB), Wuerzburg (Germany); Ehses, Philipp [Tuebingen Univ. (Germany). Dept. of Neuroimaging; Max Planck Institute for Biological Cybernetics, Tuebingen (Germany). High-Field MR Center; Jakob, Peter M. [Research Center Magnetic Resonance Bavaria (MRB), Wuerzburg (Germany); Wuerzburg Univ. (Germany). Dept. of Experimental Physics 5

    2016-05-01

    Aims: Dynamically phase-cycled radial balanced steady-state free precession (DYPR-SSFP) is a method for efficient banding artifact removal in bSSFP imaging. Based on a varying radiofrequency (RF) phase-increment in combination with a radial trajectory, DYPR-SSFP allows obtaining a banding-free image out of a single acquired k-space. The purpose of this work is to present an extension of this technique, enabling fast three-dimensional isotropic banding-free bSSFP imaging. Methods: While banding artifact removal with DYPR-SSFP relies on the applied dynamic phase-cycle, this aspect can lead to artifacts, at least when the number of acquired projections lies below a certain limit. However, by using a 3D radial trajectory with quasi-random view ordering for image acquisition, this problem is intrinsically solved, enabling 3D DYPR-SSFP imaging at or even below the Nyquist criterion. The approach is validated for brain and knee imaging at 3 Tesla. Results: Volumetric, banding-free images were obtained in clinically acceptable scan times with an isotropic resolution up to 0.56 mm. Conclusion: The combination of DYPR-SSFP with a 3D radial trajectory allows banding-free isotropic volumetric bSSFP imaging with no expense of scan time. Therefore, this is a promising candidate for clinical applications such as imaging of cranial nerves or articular cartilage.

  10. Clinical relevance of imaging proliferative activity in lung nodules

    Energy Technology Data Exchange (ETDEWEB)

    Buck, Andreas K.; Schirrmeister, Holger; Kratochwil, Clemens; Wahl, Andreas; Glatting, Gerhard; Mottaghy, Felix M.; Neumaier, Bernd; Reske, Sven N. [University of Ulm, Department of Nuclear Medicine, Ulm (Germany); Hetzel, Martin [University of Ulm, Department of Internal Medicine II - Pulmonary Medicine, Ulm (Germany); Halter, Gisela [University of Ulm, Department of Thoracic Surgery, Ulm (Germany); Moeller, Peter; Mattfeldt, Torsten [University of Ulm, Department of Pathology, Ulm (Germany)

    2005-04-01

    Recently, the thymidine analogue 3'-deoxy-3'[{sup 18}F]fluorothymidine (FLT) has been introduced for imaging proliferation with positron emission tomography (PET). In this prospective study, we examined the accuracy of FLT for differentiation of benign from malignant lung lesions and for tumour staging. A total of 47 patients with newly diagnosed pulmonary nodules on chest CT suspicious for malignancy were examined with FLT-PET in addition to routine staging procedures. A total of 43 patients also underwent 2-[{sup 18}F]fluoro-2-deoxy-D-glucose (FDG) PET imaging. Within 2 weeks, patients underwent resective surgery or core biopsy of the pulmonary lesion. Histopathology revealed malignant lung tumours in 32 patients (20 non-small cell lung cancer, 1 small cell lung cancer, 1 pulmonary carcinoid, 1 non-Hodgkin's lymphoma, nine metastases from extrapulmonary tumours) and benign lesions in 15 patients. Increased FLT uptake was exclusively related to malignant tumours. FLT-PET was false negative in two patients with non-small cell lung cancer, in the patient with a pulmonary carcinoid and in three patients with lung metastases. The sensitivity of FLT-PET for detection of lung cancer was 90%, the specificity 100% and the accuracy 94%. Fifteen out of 21 patients with lung cancer had mediastinal lymph node metastases. FLT-PET was true positive in 7/15 patients, resulting in a sensitivity of 53% for N-staging (specificity 100%, accuracy 67%). Clinical TNM stage was correctly identified in 67% (20/30) patients, compared to 85% (23/27) with FDG-PET. FLT-PET has a high specificity for the detection of malignant lung tumours. Compared with FDG, FLT-PET is less accurate for N-staging in patients with lung cancer and for detection of lung metastases. FLT-PET therefore cannot be recommended for staging of lung cancer. (orig.)

  11. CNS Cavernous Hemangioma; Imaging, Clinical Presentation and Related Anatomophysiology

    Directory of Open Access Journals (Sweden)

    Jalal Jalal Shokouhi

    2009-01-01

    Full Text Available "nClinical and imaging judgement or decision: "n- Is it a CH “CM, CA“? "n- Is it solitary, multiple or familial? "n- Is there an associated venous malformation? "n- Are there risks and consequences of hemorrhage? "n- Is the anatomic location critical and life threatening? "nCavernous malformation is a low pressure, slow flowing malformation and composes 10 – 15 % of vascular malformations. Cavernous angioma consists of enlarged sinusoidal vascular spaces, a compact mass in the brain and spinal cord, the endothelial lining is weak and blood element leakage is frequent.Calcification is possible "X – ray CT ". 75% located in the brain and 25 % in the posterior fossa and brain stem. "nAll 50% of cases are multiple and this form is familial in 80 % of cases “possibility combined with cord cavernoma“. "nExtra – medullary and extra – paranchymal forms are rare. "n- 40-60 % of the patients demonstrate seizure because of hemorrhage inside the cavernoma. "n10 – 15 % of complicated patients show significant clinical signs especially in the brain stem."n Imaging: "n1- X-ray CT: Isodense or hyperdense with frequent and heavy calcification . "nEnhanced CT may show the degree of enhancement. "n2 – By MRI: T1 may be isointense but in case of hemorrhage there is bright methemoglobin inside. By T2 and flair a thin capsule and a rim of hemosiderin – ferritin "popcorn or mulberries" and shows enhancement "GD-GRE-MRI pulse". "nCompanion of venous angioma and cavernoma is possible. "nBleeding is more likely from cavernous malformations during pregnancy. "nConclusion: CT and MRI demonstrate all forms and sites of brain and spinal cord cavernomas. "nAttention is necessary for brain stem lesions especially during pregnancy."n Treatment: 1- Medial and serial MRI controls. "n2- Radiosurgery "Gama-knife", rare. "n3- Microsurgery, very rare Multiple forms of these lesions are demonstratable in 55 patients.  

  12. Unenhanced MR Imaging in adults with clinically suspected acute appendicitis

    Energy Technology Data Exchange (ETDEWEB)

    Chabanova, Elizaveta, E-mail: elcha@heh.regionh.dk [Department of Diagnostic Radiology, Copenhagen University Hospital at Herlev (Denmark); Balslev, Ingegerd, E-mail: inbal@heh.regionh.dk [Department of Pathology, Copenhagen University Hospital at Herlev (Denmark); Achiam, Michael, E-mail: micach01@heh.regionh.dk [Department of Gastrointestinal Surgery, Copenhagen University Hospital at Herlev (Denmark); Nielsen, Yousef W., E-mail: yujwni01@heh.regionh.dk [Department of Diagnostic Radiology, Copenhagen University Hospital at Herlev (Denmark); Adamsen, Sven, E-mail: svad@heh.regionh.dk [Department of Gastrointestinal Surgery, Copenhagen University Hospital at Herlev (Denmark); Gocht-Jensen, Peter, E-mail: petgoc01@heh.reginh.dk [Department of Gastrointestinal Surgery, Copenhagen University Hospital at Herlev (Denmark); Brisling, Steffen K., E-mail: stkibr01@heh.regionh.dk [Department of Gastrointestinal Surgery, Copenhagen University Hospital at Herlev (Denmark); Logager, Vibeke B., E-mail: viloe@heh.regionh.dk [Department of Diagnostic Radiology, Copenhagen University Hospital at Herlev (Denmark); Thomsen, Henrik S., E-mail: heth@heh.regionh.dk [Department of Diagnostic Radiology, Copenhagen University Hospital at Herlev (Denmark)

    2011-08-15

    Purpose: The purpose of the study was to evaluate unenhanced Magnetic Resonance Imaging (MRI) for the diagnosis of appendicitis or another surgery-requiring condition in an adult population scheduled for emergency appendectomy based on a clinical diagnosis of suspected acute appendicitis. Materials and methods: The prospective study included 48 consecutive patients (29 female, 19 male, 18-70 years old, mean age = 37.1 years). MRI examination was designed to be comfortable and fast; no contrast was administered. The sequences were performed during quiet respiration. The MRI findings were reviewed by two radiologists and one surgeon independent of each other and compared with surgical and pathological records. Results: According to the surgical and histopathological findings 30 of 48 patients (63%) had acute appendicitis. Of the remaining 18 patients, 4 patients had no reasons for the clinical symptoms and 14 patients had other pathology. For the three reviewers the performance of MRI in the diagnosis of acute appendicitis showed the following sensitivity, specificity and accuracy ranges: 83-93%, 50-83% and 77-83%. Moderate ({kappa} = 0.51) and fair ({kappa} = 0.31) interobserver agreements in the MR diagnosis of acute appendicitis were found between the reviewers. Sensitivity, specificity and accuracy values for overall performance of MRI in detecting pelvic abnormalities were 100%, 75% (3 of 4 healthy patients were identified by MRI) and 98%, respectively. Conclusion: Unenhanced fast MRI is feasible as an additional fast screening before the appendectomy. It may prevent unnecessary surgeries. The fast MRI examination can be adequately performed on an MRI unit of broad range of field strengths.

  13. Advances on the clinical applications of the image fusion techniques in coronary heart disease

    International Nuclear Information System (INIS)

    The diagnosis of coronary heart disease increasingly depends on referring and combining the information from a variety of imaging techniques. The fusion imaging of the anatomy and function provides a convenient 'one stop' examination which improves the existing imaging examination process. The development of the image fusion techniques, such as SPECT/coronary angiography, SPECT/CT, especially PET/CT, has shown a larger value in the diagnosis, risk stratification, clinical treatment guidance and efficacy prognosis of coronary heart disease than a single imaging examination, while the more complete data of the image and the quantitative analysis provide more useful information for the clinic. (authors)

  14. Joint Probability Models of Radiology Images and Clinical Annotations

    Science.gov (United States)

    Arnold, Corey Wells

    2009-01-01

    Radiology data, in the form of images and reports, is growing at a high rate due to the introduction of new imaging modalities, new uses of existing modalities, and the growing importance of objective image information in the diagnosis and treatment of patients. This increase has resulted in an enormous set of image data that is richly annotated…

  15. Body Dysmorphic Disorder and Other Clinically Significant Body Image Concerns in Adolescent Psychiatric Inpatients: Prevalence and Clinical Characteristics

    Science.gov (United States)

    Dyl, Jennifer; Kittler, Jennifer; Phillips, Katharine A.; Hunt, Jeffrey I.

    2006-01-01

    Background: This study assessed prevalence and clinical correlates of body dysmorphic disorder (BDD), eating disorders (ED), and other clinically significant body image concerns in 208 consecutively admitted adolescent inpatients. It was hypothesized that adolescents with BDD would have higher levels of depression, anxiety, and suicidality.…

  16. Sodium-23 MRI of whole spine at 3 Tesla using a 5-channel receive-only phased-array and a whole-body transmit resonator

    Energy Technology Data Exchange (ETDEWEB)

    Malzacher, Matthias; Kalayciyan, Raffi; Konstandin, Simon; Schad, Lothar R. [Heidelberg Univ., Mannheim (Germany). Computer Assisted Clinical Medicine; Haneder, Stefan [Heidelberg Univ., Mannheim (Germany). Clinical Radiology and Nuclear Medicine; University Hospital of Cologne, Koeln (Germany). Dept. of Radiology

    2016-05-01

    Sodium magnetic resonance imaging ({sup 23}Na MRI) is a unique and non-invasive imaging technique which provides important information on cellular level about the tissue of the human body. Several applications for {sup 23}Na MRI were investigated with regard to the examination of the tissue viability and functionality for example in the brain, the heart or the breast. The {sup 23}Na MRI technique can also be integrated as a potential monitoring instrument after radiotherapy or chemotherapy. The main contribution in this work was the adaptation of {sup 23}Na MRI for spine imaging, which can provide essential information on the integrity of the intervertebral disks with respect to the early detection of disk degeneration. In this work, a transmit-only receive-only dual resonator system was designed and developed to cover the whole human spine using {sup 23}Na MRI and increase the receive sensitivity. The resonator system consisted of an already presented {sup 23}Na whole-body resonator and a newly developed 5-channel receive-only phased-array. The resonator system was first validated using bench top and phantom measurements. A threefold SNR improvement at the depth of the spine (∝7 cm) over the whole-body resonator was achieved using the spine array. {sup 23}Na MR measurements of the human spine using the transmit-only receive-only resonator system were performed on a healthy volunteer within an acquisition time of 10 minutes. A density adapted 3D radial sequence was chosen with 6 mm isotropic resolution, 49 ms repetition time and a short echo time of 540 μs. Furthermore, it was possible to quantify the tissue sodium concentration in the intervertebral discs in the lumbar region (120 ms repetition time) using this setup.

  17. Sodium-23 MRI of whole spine at 3 Tesla using a 5-channel receive-only phased-array and a whole-body transmit resonator

    International Nuclear Information System (INIS)

    Sodium magnetic resonance imaging (23Na MRI) is a unique and non-invasive imaging technique which provides important information on cellular level about the tissue of the human body. Several applications for 23Na MRI were investigated with regard to the examination of the tissue viability and functionality for example in the brain, the heart or the breast. The 23Na MRI technique can also be integrated as a potential monitoring instrument after radiotherapy or chemotherapy. The main contribution in this work was the adaptation of 23Na MRI for spine imaging, which can provide essential information on the integrity of the intervertebral disks with respect to the early detection of disk degeneration. In this work, a transmit-only receive-only dual resonator system was designed and developed to cover the whole human spine using 23Na MRI and increase the receive sensitivity. The resonator system consisted of an already presented 23Na whole-body resonator and a newly developed 5-channel receive-only phased-array. The resonator system was first validated using bench top and phantom measurements. A threefold SNR improvement at the depth of the spine (∝7 cm) over the whole-body resonator was achieved using the spine array. 23Na MR measurements of the human spine using the transmit-only receive-only resonator system were performed on a healthy volunteer within an acquisition time of 10 minutes. A density adapted 3D radial sequence was chosen with 6 mm isotropic resolution, 49 ms repetition time and a short echo time of 540 μs. Furthermore, it was possible to quantify the tissue sodium concentration in the intervertebral discs in the lumbar region (120 ms repetition time) using this setup.

  18. Evaluation of aqueductal patency in patients with hydrocephalus: Three-dimensional high-sampling efficiency technique(SPACE) versus two-dimensional turbo spin echo at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Ucar, Murat; Guryildirim, Melike; Tokgoz, Nil; Kilic, Koray; Borcek, Alp; Oner, Yusuf; Akkan, Koray; Tali, Turgut [School of Medicine, Gazi University, Ankara (Turkey)

    2014-12-15

    To compare the accuracy of diagnosing aqueductal patency and image quality between high spatial resolution three-dimensional (3D) high-sampling-efficiency technique (sampling perfection with application optimized contrast using different flip angle evolutions [SPACE]) and T2-weighted (T2W) two-dimensional (2D) turbo spin echo (TSE) at 3-T in patients with hydrocephalus. This retrospective study included 99 patients diagnosed with hydrocephalus. T2W 3D-SPACE was added to the routine sequences which consisted of T2W 2D-TSE, 3D-constructive interference steady state (CISS), and cine phase-contrast MRI (PC-MRI). Two radiologists evaluated independently the patency of cerebral aqueduct and image quality on the T2W 2D-TSE and T2W 3D-SPACE. PC-MRI and 3D-CISS were used as the reference for aqueductal patency and image quality, respectively. Inter-observer agreement was calculated using kappa statistics. The evaluation of the aqueductal patency by T2W 3D-SPACE and T2W 2D-TSE were in agreement with PC-MRI in 100% (99/99; sensitivity, 100% [83/83]; specificity, 100% [16/16]) and 83.8% (83/99; sensitivity, 100% [67/83]; specificity, 100% [16/16]), respectively (p < 0.001). No significant difference in image quality between T2W 2D-TSE and T2W 3D-SPACE (p = 0.056) occurred. The kappa values for inter-observer agreement were 0.714 for T2W 2D-TSE and 0.899 for T2W 3D-SPACE. Three-dimensional-SPACE is superior to 2D-TSE for the evaluation of aqueductal patency in hydrocephalus. T2W 3D-SPACE may hold promise as a highly accurate alternative treatment to PC-MRI for the physiological and morphological evaluation of aqueductal patency.

  19. 3-Tesla MRI によって責任病巣が確定できた外転神経麻痺型片頭痛の1例

    OpenAIRE

    神原, 啓輔; 橋本, 雅人; 大黒, 浩; 久原, 真

    2015-01-01

    今回我々は片頭痛後に外転神経麻痺を繰り返し発症し、3-Tesla MRI において外転神経麻痺の責任病巣を確定できた眼筋麻痺性片頭痛の1例を経験したので報告する。症例は14歳の女児。幼少時より片頭痛に伴う眼球運動障害を繰り返し発症していた既往がある。平成23年秋に片頭痛に伴い水平性複視が出現。神経眼科的所見としては左外転神経麻痺を認め、脳幹部画像検索を行った。3-Tesla MRI におけるFIESTA-C thinスライス(0.3mm 厚)画像では、外転神経に平行な斜め水平断において、左外転神経根出口部(root exit zone)が局所的に腫大し、さらに造影SPGR 法において同部位が著明な造影効果を示した。またFLAIR 法において大脳皮質に脱髄斑を認めた。これらの画像および臨床所見より、眼筋麻痺性片頭痛および多発性硬化症と診断した。ステロイドの全身投与を行ったところ、外転神経麻痺の改善がみられ、画像検査においても左外転神経根の造影効果は減少した。近年、眼筋麻痺性片頭痛のMRI 画像の特徴として動眼神経根出口部の菱形様腫脹および造影効果が報告されている。本症も外転神経根に...

  20. Dynamic Contrast-Enhanced MRI Parameters as Biomarkers in Assessing Head and Neck Lesions After Chemoradiotherapy Using a Wide-Bore 3 Tesla Scanner.

    Science.gov (United States)

    Lerant, Gergely; Sarkozy, Peter; Takacsi-Nagy, Zoltan; Polony, Gabor; Tamas, Laszlo; Toth, Erika; Boer, Andras; Javor, Laszlo; Godeny, Maria

    2015-09-01

    Pilot studies have shown promising results in characterizing head and neck tumors (HNT) using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), differentiating between malignant and benign lesions and evaluating changes in response to chemoradiotherapy (CRT). Our aim was to find DCE-MRI parameters, biomarkers in evaluating the post-CRT status. Two hundred and five patients with head and neck lesions were examined with DCE-MRI sequences. The time intensity curves (TIC) were extracted and processed to acquire time-to-peak (TTP), relative maximum enhancement (RME), relative wash-out (RWO), and two new parameters attack and decay. These parameters were analyzed using univariate tests in SPSS (Statistical Package for the Social Sciences, version 17, SPSS Inc. Chicago, USA) to identify parameters that could be used to infer tumor malignancy and post-CRT changes. Multiple parameters of curve characteristics were significantly different between malignant tumors after CRT (MACRT) and changes caused by CRT. The best-performing biomarkers were the attack and the decay. We also found multiple significant (p < 0.05) parameters for both the benign and malignant status as well as pre- and post-CRT status. Our large cohort of data supports the increasing role of DCE-MRI in HNT differentiation, particularly for the assessment of post-CRT status along with accurate morphological imaging. PMID:25920367

  1. Unique roles of SPET brain imaging in clinical and research studies

    International Nuclear Information System (INIS)

    The increasing availability of PET imaging in Nuclear medicine expands the armamentarium of clinical and research tools for improving diagnosis and treatment of neuropsychiatric disorders. Nonetheless, the role of SPEC imaging remains critical to both research and clinical practice. The development of rational strategies for guiding the selection of imaging modalities flows from primarily the nature of the clinical or research question and the availability of appropriate radiopharmaceuticals. There has been extensive SPECT and PET work in Parkinson's disease (PD) which highlights the value of both these scintigraphic modalities. Three main areas of interest in PD include imaging for improving diagnostic accuracy, for monitoring the progression of disease, and for assessing the therapeutic efficacy of drugs with neoroprotective potential. The demands of the clinical or research question posed to imaging dictates the selection of radiotracer and imaging modality. Diagnosis of PD represents the easiest challenge with many imaging bio markers showing high sensitivity for detecting abnormal reduction of dopaminergic function based on qualitative review of images. On the other hand, using imaging to evaluate treatments which purportedly slow the rate of disease progression, indicated by the reduction of the rate of loss in a quantitative imaging signal in patients studied over time, represents the most rigorous requirement of the imaging measure. In each of these applications presynaptic markers of dopaminergic function using SPECT and PET have been extremely valuable. Review of neuroimaging studies of PD provides a useful example of optimized approaches to clinical and research studies in neuropsychiatric disorders

  2. Clinical PET-MR Imaging in Breast Cancer and Lung Cancer.

    Science.gov (United States)

    Rice, Samuel L; Friedman, Kent P

    2016-10-01

    Hybrid imaging systems have dramatically improved thoracic oncology patient care over the past 2 decades. PET-MR imaging systems have the potential to further improve imaging of thoracic neoplasms, resulting in diagnostic and therapeutic advantages compared with current MR imaging and PET-computed tomography systems. Increasing soft tissue contrast and lesion sensitivity, improved image registration, reduced radiation exposure, and improved patient convenience are immediate clinical advantages. Multiparametric quantitative imaging capabilities of PET-MR imaging have the potential to improve understanding of the molecular mechanisms of cancer and treatment effects, potentially guiding improvements in diagnosis and therapy. PMID:27593245

  3. Image artifacts from MR-based attenuation correction in clinical, whole-body PET/MRI

    DEFF Research Database (Denmark)

    Keller, Sune H; Holm, Søren; Hansen, Adam E;

    2013-01-01

    Integrated whole-body PET/MRI tomographs have become available. PET/MR imaging has the potential to supplement, or even replace combined PET/CT imaging in selected clinical indications. However, this is true only if methodological pitfalls and image artifacts arising from novel MR-based attenuation...

  4. High frame rate photoacoustic imaging at 7000 frames per second using clinical ultrasound system.

    Science.gov (United States)

    Sivasubramanian, Kathyayini; Pramanik, Manojit

    2016-02-01

    Photoacoustic tomography, a hybrid imaging modality combining optical and ultrasound imaging, is gaining attention in the field of medical imaging. Typically, a Q-switched Nd:YAG laser is used to excite the tissue and generate photoacoustic signals. But, such photoacoustic imaging systems are difficult to translate into clinical applications owing to their high cost, bulky size often requiring an optical table to house such lasers. Moreover, the low pulse repetition rate of few tens of hertz prevents them from being used in high frame rate photoacoustic imaging. In this work, we have demonstrated up to 7000 Hz photoacoustic imaging (B-mode) and measured the flow rate of a fast moving object. We used a ~140 nanosecond pulsed laser diode as an excitation source and a clinical ultrasound imaging system to capture and display the photoacoustic images. The excitation laser is ~803 nm in wavelength with ~1.4 mJ energy per pulse. So far, the reported 2-dimensional photoacoustic B-scan imaging is only a few tens of frames per second using a clinical ultrasound system. Therefore, this is the first report on 2-dimensional photoacoustic B-scan imaging with 7000 frames per second. We have demonstrated phantom imaging to view and measure the flow rate of ink solution inside a tube. This fast photoacoustic imaging can be useful for various clinical applications including cardiac related problems, where the blood flow rate is quite high, or other dynamic studies.

  5. Measurement of brain perfusion, blood volume, and blood-brain barrier permeability, using dynamic contrast-enhanced T(1)-weighted MRI at 3 tesla

    DEFF Research Database (Denmark)

    Larsson, Henrik B W; Courivaud, Frédéric; Rostrup, Egill;

    2009-01-01

    Assessment of vascular properties is essential to diagnosis and follow-up and basic understanding of pathogenesis in brain tumors. In this study, a procedure is presented that allows concurrent estimation of cerebral perfusion, blood volume, and blood-brain permeability from dynamic T(1)-weighted...... imaging of a bolus of a paramagnetic contrast agent passing through the brain. The methods are applied in patients with brain tumors and in healthy subjects. Perfusion was estimated by model-free deconvolution using Tikhonov's method (gray matter/white matter/tumor: 72 +/- 16/30 +/- 8/56 +/- 45 mL/100 g...... on a pixel-by-pixel basis of cerebral perfusion, cerebral blood volume, and blood-brain barrier permeability....

  6. Simultaneous measurement of kidney function by dynamic contrast enhanced MRI and FITC-sinistrin clearance in rats at 3 tesla: initial results.

    Directory of Open Access Journals (Sweden)

    Frank G Zöllner

    Full Text Available Glomerular filtration rate (GFR is an essential parameter of kidney function which can be measured by dynamic contrast enhanced magnetic resonance imaging (MRI-GFR and transcutaneous approaches based on fluorescent tracer molecules (optical-GFR. In an initial study comparing both techniques in separate measurements on the same animal, the correlation of the obtained GFR was poor. The goal of this study was to investigate if a simultaneous measurement was feasible and if thereby, the discrepancies in MRI-GFR and optical-GFR could be reduced. For the experiments healthy and unilateral nephrectomised (UNX Sprague Dawley (SD rats were used. The miniaturized fluorescent sensor was fixed on the depilated back of an anesthetized rat. A bolus of 5 mg/100 g b.w. of FITC-sinistrin was intravenously injected. For dynamic contrast enhanced perfusion imaging (DCE-MRI a 3D time-resolved angiography with stochastic trajectories (TWIST sequence was used. By means of a one compartment model the excretion half-life (t1/2 of FITC-sinistrin was calculated and converted into GFR. GFR from DCE-MRI was calculated by fitting pixel-wise a two compartment renal filtration model. Mean cortical GFR and GFR by FITC-sinistrin were compared by Bland-Altman plots and pair-wise t-test. Results show that a simultaneous GFR measurement using both techniques is feasible. Mean optical-GFR was 4.34 ± 2.22 ml/min (healthy SD rats and 2.34 ± 0.90 ml/min (UNX rats whereas MRI-GFR was 2.10 ± 0.64 ml/min (SD rats and 1.17 ± 0.38 ml/min (UNX rats. Differences between healthy and UNX rats were significant (p<0.05 and almost equal percentage difference (46.1% and 44.3% in mean GFR were assessed with both techniques. Overall mean optical-GFR values were approximately twice as high compared to MRI-GFR values. However, compared to a previous study, our results showed a higher agreement. In conclusion, the possibility to use the transcutaneous method in MRI may have a huge impact in

  7. Observation of contrast enhancement in the cochlear fluid space of healthy subjects using a 3D-FLAIR sequence at 3 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Naganawa, Shinji; Komada, Tomomi; Fukatsu, Hiroshi; Ishigaki, Takeo [Nagoya University Graduate School of Medicine, Department of Radiology, Nagoya (Japan); Takizawa, Osamu [Siemens-Asahi Medical Technologies Ltd., Tokyo (Japan)

    2006-03-15

    In animals, the enhancement of perilymph in the cochlea has been reported using 1.25 mmol/kg of Gd-DTPA, allowing the separate visualisation of perilymph and endolymph for the diagnosis of Meniere's disease. The purpose of this study was three-fold: (1) to determine the optimal timing for detecting cochlear fluid enhancement using 3D-FLAIR (fluid-attenuated inversion recovery) after intravenous administration of 0.1 mmol/kg of Gd-DTPA in healthy human subjects; (2) to examine the reliability of enhancement in multiple healthy subjects; and (3) to investigate whether endolymph and perilymph space can be visually discriminated. In two healthy subjects, 3D-FLAIR images were obtained before, immediately after and 2 h, 4 h and 6 h after the injection. Three more healthy subjects were scanned before and 4 h after the injection. In all four ears of the initial two subjects, cochlear fluid was found to be most intensely enhanced 4 h after the injection. In all of the additional three subjects, the cochlear fluid signal had increased after 4 h from injection. However, visual differentiation of endolymph and perilymph fluid could not be achieved. Using 3D-FLAIR and Gd-DTPA, cochlear fluid enhancement can be observed in healthy human ears, even with a single dose of contrast-medium injection. (orig.)

  8. Intradiurnal fluctuations of off-resonance saturation effects in healthy human achilles tendons assessed with a 3D ultrashort echo time MRI sequence at 3 tesla

    Energy Technology Data Exchange (ETDEWEB)

    Grosse, U.; Syha, R.; Kessler, D.E.; Bongers, M.; Seith, F.; Nikolaou, K.; Springer, F. [University Hospital Tuebingen (Germany). Dept. of Diagnostic and Interventional Radiology; Partovi, S.; Robbin, M. [Case Western Reserve Univ., Cleveland, OH (United States). Dept. of Radiology; Schick, F. [University Hospital Tuebingen (Germany). Section on Experimental Radiology

    2015-11-15

    The purpose of this study was to evaluate whether gravitational interstitial fluid accumulation in healthy subjects has an impact on off-resonance saturation ratios (OSR) or the volume of the Achilles tendon after a prolonged time of reduced levels of physical activity. 7 healthy volunteers were repeatedly investigated on 3 consecutive days on a 3 T whole body MR scanner using an ultrashort echo time (UTE) imaging sequence with a Gaussian off-resonance saturation pulse at a frequency offset of 2000 Hz to calculate OSR values. For accurate volumetric quantification of the Achilles tendon, a newly developed contour detection snake algorithm was applied on high-resolution isotropic T2-weighted SPACE sequence datasets. Single-measure intraclass correlation coefficients (ICC) were calculated to estimate test-retest reliability. For OSR and tendon volume measurements on three consecutive days, excellent reproducibility could be achieved with ICC values above 0.96 and 0.97, respectively. Comparing the results of all three days, a statistically significant mean individual percentage decrease (-4.1 ± 1.5 %; p=0.001) of calculated tendon OSR values was found for the evening measurements. No statistically significant difference between tendon volumes in the morning and the evening could be detected (p=0.589). The results of this in-vivo study demonstrate a significant influence of gravitational interstitial fluid accumulation after reduced physical activity on OSR values in the Achilles tendon, but not on tendon volume. Taken together with the demonstrated excellent reproducibility, these findings are important for future studies investigating temporal changes of the Achilles tendon microstructure.

  9. Modern dental imaging: a review of the current technology and clinical applications in dental practice

    Energy Technology Data Exchange (ETDEWEB)

    Vandenberghe, Bart; Jacobs, Reinhilde [Katholieke Universiteit Leuven, Oral Imaging Centre, Faculty of Medicine, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Leuven (Belgium); Bosmans, Hilde [Katholieke Universiteit Leuven, Radiology Section, Department of Medical Diagnostic Sciences, Leuven (Belgium)

    2010-11-15

    A review of modern imaging techniques commonly used in dental practice and their clinical applications is presented. The current dental examinations consist of intraoral imaging with digital indirect and direct receptors, while extraoral imaging is divided into traditional tomographic/panoramic imaging and the more recently introduced cone beam computed tomography. Applications, limitations and current trends of these dental ''in-office'' radiographic techniques are discussed. (orig.)

  10. PET/SPECT molecular imaging in clinical neuroscience: recent advances in the investigation of CNS diseases

    OpenAIRE

    Lu, Feng-Mei; Yuan, Zhen

    2015-01-01

    Molecular imaging is an attractive technology widely used in clinical practice that greatly enhances our understanding of the pathophysiology and treatment in central nervous system (CNS) diseases. It is a novel multidisciplinary technique that can be defined as real-time visualization, in vivo characterization and qualification of biological processes at the molecular and cellular level. It involves the imaging modalities and the corresponding imaging agents. Nowadays, molecular imaging in n...

  11. An observer study for direct comparison of clinical efficacy of electronic to film portal images

    International Nuclear Information System (INIS)

    Purpose: To directly compare clinical efficacy of electronic to film portal images. Methods and Materials: An observer study was designed to compare clinical efficacy of electronic to film portal images acquired using a liquid matrix ion-chamber electronic portal imaging device and a conventional metal screen/film system. Both images were acquired simultaneously for each treatment port and the electronic portal images were printed on gray-level thermal paper. Four radiation oncologists served as observers and evaluated a total of 44 sets of images for four different treatment sites: lung, pelvis, brain, and head/neck. Each set of images included a simulation image, a double-exposure portal film, and video paper prints of electronic portal images. Eight to nine anatomical landmarks were selected from each treatment site. Each observer was asked to rate each landmark in terms of its clinical visibility and to rate the ease of making the pertinent verification decision in the corresponding electronic and film portal images with the aid of the simulation image. Results: Ratings for the visibility of landmarks and for the verification decision of treatment ports were similar for electronic and film images for most landmarks. However, vertebral bodies and several landmarks in the pelvis such as the acetabulum and pubic symphysis were more visible in the portal film images than in the electronic portal images. Conclusion: The visibility of landmarks in electronic portal images is comparable to that in film portal images. Verification of treatment ports based only on electronic portal images acquired using an electronic portal imaging device is generally achievable

  12. Evaluation of proton MR spectroscopy at 3 Tesla without endorectal coil in patients with a localized prostate cancer treated with exclusive radiotherapy

    International Nuclear Information System (INIS)

    Prostate cancer is the most frequent tumour affecting the male population. When the prostate is not removed and is treated with radiation therapy, PSA slowly decreases over time to reach its nadir, even sometimes 18 to 24 months after the completion of radiation therapy without combined androgen suppression therapy. When combined with hormones, PSA falls abruptly with no possibility to perceive the impact of either hormones or radiation effects on PSA.The optimal value of PSA that should be reached after radiation therapy (nadir) and time to this nadir are still unclear.Even when a satisfactory value of the PSA nadir is reached, on-going variations of the PSA and its 'bounce' effects, which occurs in 20% to 40% of the cases.Proton magnetic resonance spectroscopy allows one to assess the relative concentration of Choline and Citrate. Choline is a metabolite of whose concentration is often increased in the presence of a tumour, whereas the synthesis and the oxidation of Citrate are two decisive elements of the normal metabolism, functional abilities, growth, reproduction and survival of prostatic cells. This MR technique can be performed in combination with diffusion-weighted MRI and DCE-MRI (multi-parametric MRI).The goal of our study was to evaluate the feasibility of a 3D CSI proton MR spectroscopy of the entire prostate gland at 3.0 Tesla without an endorectal coil among patients with a localised prostate cancer treated with radiation therapy, with or without hormones. We first have classified spectra in a 5-point scale (from benign: class I, to malign: class V) based on a control group with radical prostatectomy as the standard of reference. This classification enabled us to establish a strong correlation between malignant spectra or the metabolic tumor volume and clinically validated prognostic factors.In parallel, a prospective clinical trial of which the aim is to Evaluate the Response to Irradiation with proton MR Spectroscopy (ERIS trial) has been set up to

  13. Regional Metabolic Changes in the Hippocampus and Posterior Cingulate Area Detected with 3-Tesla Magnetic Resonance Spectroscopy in Patients with Mild Cognitive Impairment and Alzheimer Disease

    Energy Technology Data Exchange (ETDEWEB)

    Zhiqun Wang; Cheng Zhao; Kuncheng Li (Dept. of Radiology, Xuanwu Hospital, Capital Medical Univ., Beijing (China)); Lei Yu; Weidong Zhou (Dept. of Neurology, Xuanwu Hospital, Capital Medical Univ., Beijing (China))

    2009-04-15

    Background: Magnetic resonance spectroscopy (MRS) plays an important role in early diagnosis of Alzheimer disease (AD). There are many reports on MRS studies among individuals with AD and mild cognitive impairment (MCI). However, very few studies have compared spectroscopic data of different limbic regions among AD and MCI subjects. Purpose: To compare metabolite changes of different regions in the brain of AD and MCI patients by using 3.0T short-echo-time MRS. Material and Methods: Metabolite ratios in the hippocampus and posterior cingulate area were compared in a group of patients with AD (n=16), MCI (n=16), and normal subjects as a control group (n=16). Clinical neuropsychological tests were measured in all subjects. Results: In the hippocampus, there were significant differences in N-acetylaspartate (NAA)/creatine (Cr), myo-inositol (mI)/Cr, and mI/NAA ratios among the three groups. However, there were no significant differences in choline (Cho)/Cr ratio among the three groups. In the posterior cingulate area, there were no significant differences in the NAA/Cr, Cho/Cr, and mI/Cr ratios among the three groups. However, there were significant differences in mI/NAA ratio between patients with AD and the control group, and between the AD and MCI groups. In addition, there was significant correlation between mI/NAA ratio and Mini Mental Status Exam (MMSE) score in subjects with AD and MCI. Conclusion: The study reveals that the elevation of mI/NAA ratio in the hippocampus is more significant than that in the posterior cingulate area, which corresponds to the pathologic procession of AD. The ratios of mI/NAA in the hippocampus and in the posterior cingulate area together provide valuable discrimination among the three groups (AD, MCI, and controls). There is a significant correlation between mI/NAA ratio and cognitive decline.

  14. Retrieving clinically relevant diabetic retinopathy images using a multi-class multiple-instance framework

    Science.gov (United States)

    Chandakkar, Parag S.; Venkatesan, Ragav; Li, Baoxin

    2013-02-01

    Diabetic retinopathy (DR) is a vision-threatening complication from diabetes mellitus, a medical condition that is rising globally. Unfortunately, many patients are unaware of this complication because of absence of symptoms. Regular screening of DR is necessary to detect the condition for timely treatment. Content-based image retrieval, using archived and diagnosed fundus (retinal) camera DR images can improve screening efficiency of DR. This content-based image retrieval study focuses on two DR clinical findings, microaneurysm and neovascularization, which are clinical signs of non-proliferative and proliferative diabetic retinopathy. The authors propose a multi-class multiple-instance image retrieval framework which deploys a modified color correlogram and statistics of steerable Gaussian Filter responses, for retrieving clinically relevant images from a database of DR fundus image database.

  15. Clinical data compression with a picture archiving and communications system image workstation

    International Nuclear Information System (INIS)

    The picture archiving communications system (PACS) started in 1985 at Kyoto University Hospital has been working for 4 years in a clinical environment. Three x-ray CT, MR imaging, chest radiography, and digital subtraction angiography (DSAs) units have already been linked with the system. Because the long-term archiving of the image data and the increase in the number of image modalities have caused system overload, efforts should be made to reduce the image data. This paper reports on an image workstation with a personal computer to create an image summary with reporting system

  16. Evaluation of clinical image processing algorithms used in digital mammography.

    Science.gov (United States)

    Zanca, Federica; Jacobs, Jurgen; Van Ongeval, Chantal; Claus, Filip; Celis, Valerie; Geniets, Catherine; Provost, Veerle; Pauwels, Herman; Marchal, Guy; Bosmans, Hilde

    2009-03-01

    Screening is the only proven approach to reduce the mortality of breast cancer, but significant numbers of breast cancers remain undetected even when all quality assurance guidelines are implemented. With the increasing adoption of digital mammography systems, image processing may be a key factor in the imaging chain. Although to our knowledge statistically significant effects of manufacturer-recommended image processings have not been previously demonstrated, the subjective experience of our radiologists, that the apparent image quality can vary considerably between different algorithms, motivated this study. This article addresses the impact of five such algorithms on the detection of clusters of microcalcifications. A database of unprocessed (raw) images of 200 normal digital mammograms, acquired with the Siemens Novation DR, was collected retrospectively. Realistic simulated microcalcification clusters were inserted in half of the unprocessed images. All unprocessed images were subsequently processed with five manufacturer-recommended image processing algorithms (Agfa Musica 1, IMS Raffaello Mammo 1.2, Sectra Mamea AB Sigmoid, Siemens OPVIEW v2, and Siemens OPVIEW v1). Four breast imaging radiologists were asked to locate and score the clusters in each image on a five point rating scale. The free-response data were analyzed by the jackknife free-response receiver operating characteristic (JAFROC) method and, for comparison, also with the receiver operating characteristic (ROC) method. JAFROC analysis revealed highly significant differences between the image processings (F = 8.51, p < 0.0001), suggesting that image processing strongly impacts the detectability of clusters. Siemens OPVIEW2 and Siemens OPVIEW1 yielded the highest and lowest performances, respectively. ROC analysis of the data also revealed significant differences between the processing but at lower significance (F = 3.47, p = 0.0305) than JAFROC. Both statistical analysis methods revealed that the

  17. Evaluation of clinical image processing algorithms used in digital mammography.

    Science.gov (United States)

    Zanca, Federica; Jacobs, Jurgen; Van Ongeval, Chantal; Claus, Filip; Celis, Valerie; Geniets, Catherine; Provost, Veerle; Pauwels, Herman; Marchal, Guy; Bosmans, Hilde

    2009-03-01

    Screening is the only proven approach to reduce the mortality of breast cancer, but significant numbers of breast cancers remain undetected even when all quality assurance guidelines are implemented. With the increasing adoption of digital mammography systems, image processing may be a key factor in the imaging chain. Although to our knowledge statistically significant effects of manufacturer-recommended image processings have not been previously demonstrated, the subjective experience of our radiologists, that the apparent image quality can vary considerably between different algorithms, motivated this study. This article addresses the impact of five such algorithms on the detection of clusters of microcalcifications. A database of unprocessed (raw) images of 200 normal digital mammograms, acquired with the Siemens Novation DR, was collected retrospectively. Realistic simulated microcalcification clusters were inserted in half of the unprocessed images. All unprocessed images were subsequently processed with five manufacturer-recommended image processing algorithms (Agfa Musica 1, IMS Raffaello Mammo 1.2, Sectra Mamea AB Sigmoid, Siemens OPVIEW v2, and Siemens OPVIEW v1). Four breast imaging radiologists were asked to locate and score the clusters in each image on a five point rating scale. The free-response data were analyzed by the jackknife free-response receiver operating characteristic (JAFROC) method and, for comparison, also with the receiver operating characteristic (ROC) method. JAFROC analysis revealed highly significant differences between the image processings (F = 8.51, p < 0.0001), suggesting that image processing strongly impacts the detectability of clusters. Siemens OPVIEW2 and Siemens OPVIEW1 yielded the highest and lowest performances, respectively. ROC analysis of the data also revealed significant differences between the processing but at lower significance (F = 3.47, p = 0.0305) than JAFROC. Both statistical analysis methods revealed that the

  18. Planar scintigraphic imaging of the gastrointestinal tract in clinical practice.

    Science.gov (United States)

    Middleton, Michael L; Strober, Mark D

    2012-01-01

    In the last 30 years, nuclear medicine has paralleled other imaging fields with the development of 3-dimensional techniques, including single-photon emission computed tomography and positron emission tomography. However, conventional nuclear medicine planar scintigraphy remains a common procedure at most imaging centers. Gastrointestinal studies constitute a significant portion of these planar procedures. The most common gastrointestinal studies, including hepatobiliary, gastric emptying, and gastrointestinal bleeding evaluations, resemble their original protocol. However, serial improvements have optimized the diagnostic efficacy of these procedures. Conventional Technetium-99m sulfur colloid liver/spleen imaging and hepatic blood pool imaging with labeled red blood cells now mainly serve an adjunctive role in the evaluation of equivocal findings on computed tomography. Salivary gland imaging is a less commonly requested evaluation, but can be used to evaluate functional capacity in some disease entities. PMID:22117811

  19. Fuzzy Logic Based Edge Detection in Smooth and Noisy Clinical Images.

    Directory of Open Access Journals (Sweden)

    Izhar Haq

    Full Text Available Edge detection has beneficial applications in the fields such as machine vision, pattern recognition and biomedical imaging etc. Edge detection highlights high frequency components in the image. Edge detection is a challenging task. It becomes more arduous when it comes to noisy images. This study focuses on fuzzy logic based edge detection in smooth and noisy clinical images. The proposed method (in noisy images employs a 3 × 3 mask guided by fuzzy rule set. Moreover, in case of smooth clinical images, an extra mask of contrast adjustment is integrated with edge detection mask to intensify the smooth images. The developed method was tested on noise-free, smooth and noisy images. The results were compared with other established edge detection techniques like Sobel, Prewitt, Laplacian of Gaussian (LOG, Roberts and Canny. When the developed edge detection technique was applied to a smooth clinical image of size 270 × 290 pixels having 24 dB 'salt and pepper' noise, it detected very few (22 false edge pixels, compared to Sobel (1931, Prewitt (2741, LOG (3102, Roberts (1451 and Canny (1045 false edge pixels. Therefore it is evident that the developed method offers improved solution to the edge detection problem in smooth and noisy clinical images.

  20. Fuzzy Logic Based Edge Detection in Smooth and Noisy Clinical Images.

    Science.gov (United States)

    Haq, Izhar; Anwar, Shahzad; Shah, Kamran; Khan, Muhammad Tahir; Shah, Shaukat Ali

    2015-01-01

    Edge detection has beneficial applications in the fields such as machine vision, pattern recognition and biomedical imaging etc. Edge detection highlights high frequency components in the image. Edge detection is a challenging task. It becomes more arduous when it comes to noisy images. This study focuses on fuzzy logic based edge detection in smooth and noisy clinical images. The proposed method (in noisy images) employs a 3 × 3 mask guided by fuzzy rule set. Moreover, in case of smooth clinical images, an extra mask of contrast adjustment is integrated with edge detection mask to intensify the smooth images. The developed method was tested on noise-free, smooth and noisy images. The results were compared with other established edge detection techniques like Sobel, Prewitt, Laplacian of Gaussian (LOG), Roberts and Canny. When the developed edge detection technique was applied to a smooth clinical image of size 270 × 290 pixels having 24 dB 'salt and pepper' noise, it detected very few (22) false edge pixels, compared to Sobel (1931), Prewitt (2741), LOG (3102), Roberts (1451) and Canny (1045) false edge pixels. Therefore it is evident that the developed method offers improved solution to the edge detection problem in smooth and noisy clinical images.

  1. Learning clinically useful information from images: Past, present and future.

    Science.gov (United States)

    Rueckert, Daniel; Glocker, Ben; Kainz, Bernhard

    2016-10-01

    Over the last decade, research in medical imaging has made significant progress in addressing challenging tasks such as image registration and image segmentation. In particular, the use of model-based approaches has been key in numerous, successful advances in methodology. The advantage of model-based approaches is that they allow the incorporation of prior knowledge acting as a regularisation that favours plausible solutions over implausible ones. More recently, medical imaging has moved away from hand-crafted, and often explicitly designed models towards data-driven, implicit models that are constructed using machine learning techniques. This has led to major improvements in all stages of the medical imaging pipeline, from acquisition and reconstruction to analysis and interpretation. As more and more imaging data is becoming available, e.g., from large population studies, this trend is likely to continue and accelerate. At the same time new developments in machine learning, e.g., deep learning, as well as significant improvements in computing power, e.g., parallelisation on graphics hardware, offer new potential for data-driven, semantic and intelligent medical imaging. This article outlines the work of the BioMedIA group in this area and highlights some of the challenges and opportunities for future work. PMID:27344105

  2. Detecting breast microcalcifications using super-resolution ultrasound imaging: a clinical study

    Science.gov (United States)

    Huang, Lianjie; Labyed, Yassin; Hanson, Kenneth; Sandoval, Daniel; Pohl, Jennifer; Williamson, Michael

    2013-03-01

    Imaging breast microcalcifications is crucial for early detection and diagnosis of breast cancer. It is challenging for current clinical ultrasound to image breast microcalcifications. However, new imaging techniques using data acquired with a synthetic-aperture ultrasound system have the potential to significantly improve ultrasound imaging. We recently developed a super-resolution ultrasound imaging method termed the phase-coherent multiple-signal classification (PC-MUSIC). This signal subspace method accounts for the phase response of transducer elements to improve image resolution. In this paper, we investigate the clinical feasibility of our super-resolution ultrasound imaging method for detecting breast microcalcifications. We use our custom-built, real-time synthetic-aperture ultrasound system to acquire breast ultrasound data for 40 patients whose mammograms show the presence of breast microcalcifications. We apply our super-resolution ultrasound imaging method to the patient data, and produce clear images of breast calcifications. Our super-resolution ultrasound PC-MUSIC imaging with synthetic-aperture ultrasound data can provide a new imaging modality for detecting breast microcalcifications in clinic without using ionizing radiation.

  3. Recent advances in computational methods and clinical applications for spine imaging

    CERN Document Server

    Glocker, Ben; Klinder, Tobias; Li, Shuo

    2015-01-01

    This book contains the full papers presented at the MICCAI 2014 workshop on Computational Methods and Clinical Applications for Spine Imaging. The workshop brought together scientists and clinicians in the field of computational spine imaging. The chapters included in this book present and discuss the new advances and challenges in these fields, using several methods and techniques in order to address more efficiently different and timely applications involving signal and image acquisition, image processing and analysis, image segmentation, image registration and fusion, computer simulation, image based modeling, simulation and surgical planning, image guided robot assisted surgical and image based diagnosis. The book also includes papers and reports from the first challenge on vertebra segmentation held at the workshop.

  4. New directions in clinical imaging of cortical dysplasias.

    Science.gov (United States)

    Madan, Neel; Grant, P Ellen

    2009-10-01

    Neuroimaging is essential in the work-up of patients with intractable epilepsy. In pediatric patients with medically refractory epilepsy, cortical dysplasias account for a large percentage of the epileptogenic substrate. Unfortunately, these are also the most subtle lesions to identify. For this reason, there has been ongoing interest in utilizing new advanced magnetic resonance imaging (MRI) techniques to improve the ability to identify, diagnose, characterize, and delineate cortical dysplasias. Technologic gains such as multichannel coils (32 phased array and beyond) and higher field strengths (3T, 7T, and greater) coupled with newer imaging sequences such as arterial spin labeling (ASL), susceptibility weighted imaging (SWI) and diffusion tensor/spectrum imaging (DTI/DSI) are likely to increase yield. Improved MRI techniques coupled with a multimodality approach including magnetoencephalography (MEG), positron emission tomography (PET), and other techniques will increase sensitivity and specificity for identifying cortical dysplasias. PMID:19761449

  5. Early neurological deterioration after thrombolysis: Clinical and imaging predictors

    DEFF Research Database (Denmark)

    Simonsen, Claus Z; Schmitz, Marie Louise; Hjørringgaard Madsen, Mette;

    2016-01-01

    BACKGROUND: National Institutes of Health Stroke Scale is the most common scale used in stroke patients. An increase of four points or more within 24 h signifies early neurological deterioration. We aimed to establish how often early neurological deterioration occurs in a cohort selected...... by magnetic resonance imaging and which factors predicted early neurological deterioration. METHODS: In this single-center study, we collected epidemiological, imaging and outcome data on 569 consecutive patients undergoing reperfusion therapy after magnetic resonance imaging selection. RESULTS: Of these, 33...... (5.8%) experienced early neurological deterioration. Seven were due to a symptomatic intracerebral hemorrhage, 23 were caused by extension of ischemia on follow-up imaging and three were due to progression on the basis of small vessel disease. Early neurological deterioration was predicted...

  6. Clinical software VIII for magnetic resonance imaging systems

    Energy Technology Data Exchange (ETDEWEB)

    Kohno, Satoru; Takeo, Kazuhiro [Medical Applications Department, Medical Systems Division, Shimadzu Corporation, Kyoto (Japan)

    2001-02-01

    This report describes the latest techniques of MRA (magnetic resonance angiography) and the brain attack diagnosis protocol which are now effectively utilized in the Shimadzu-Marconi MAGNEX ECLIPSE MRI (magnetic resonance imaging) system (1.5 tesla type) and the MAGNEX POLARIS MRI system (1.0 tesla type). As for the latest techniques for MRA, this report refers to the SLINKY (sliding interleaved ky) technique, which provides high-resolution images over a wide range in the direction of slice, without using contrast agent, and to the iPass technique which enables highly reliable CE-MRA (contrast-enhanced magnetic resonance angiography), through easy and simple operation. Also reported are the techniques of diffusion imaging and perfusion imaging, utilized for stroke assessment. (author)

  7. Assessing image-guided implant surgery in today's clinical practice.

    Science.gov (United States)

    Norkin, Frederic J; Ganeles, Jeffrey; Zfaz, Samuel; Modares, Alireza

    2013-01-01

    As implant dentistry has progressed, greater emphasis has been placed on natural-looking tooth replacement, minimally invasive techniques, and better cost efficiencies, with implant positioning being guided by the desired prosthetic outcome. Image-guided surgery is a technique that merges preoperative diagnostic imaging with computer-based planning tools to facilitate surgical and restorative plans and procedures. This article discusses the intricacies of guided implant surgery, including 3-dimensional presurgical planning and the challenges of maintaining guide stability during surgical execution.

  8. The American College of Radiology Imaging Network (ACRIN) – Clinical Trials of Diagnostic Imaging and Image-Guided Treatment

    OpenAIRE

    Hillman, Bruce J.; Gatsonis, Constantine

    2008-01-01

    The American College of Radiology Imaging Network (ACRIN) is the youngest of the NCI cooperative groups. ACRIN trials are directed towards evaluating the applications of diagnostic imaging and image-guided treatment to cancer. As ACRIN begins its third funding cycle, the organization is increasingly emphasizing several themes: linking imaging surveillance to pre-imaging testing for disease to improve the efficiency of cancer screening; the evaluation of imaging tests as biomarkers for molecul...

  9. A Dynamic Imaging Database for 3-D Morphologic Analysis and Clinical Assessment in Diagnostic Radiology

    OpenAIRE

    Niculescu, Gabriela; Toni, Louay; Foran, David J.; Nosher, John L.; DeMarco, J. Kevin

    2002-01-01

    Modern imaging techniques such as MRI and CT have become invaluable clinical and research tools for visualizing internal organs and anatomic structures, non-invasively. We present a dynamic imaging database for performing comparative morphologic studies in diagnostic radiology to facilitate clinical assessment. The prototype system utilizes a double elliptic Fourier transform to characterize shape in three dimensions. A prototype system was used to evaluate neuroanatomy from MR brain scans of...

  10. Distinguishing clinical and imaging features of nodular regenerative hyperplasia and large regenerative nodules of the liver

    Energy Technology Data Exchange (ETDEWEB)

    Ames, J.T. [Departments of Radiology, University of Pittsburgh Medical Center Pittsburgh, Pennsylvania (United States); Federle, M.P., E-mail: federle@stanford.ed [Departments of Radiology, University of Pittsburgh Medical Center Pittsburgh, Pennsylvania (United States); Chopra, K. [Departments of Gastroenterology, University of Pittsburgh Medical Center Pittsburgh, Pennsylvania (United States)

    2009-12-15

    Aim: Nodular regenerative hyperplasia (NRH) and large regenerative nodules (LRN) are distinct types of hepatocellular nodules that have been confused in the radiology literature. However, distinction is critical because their clinical significance is quite different. Our purpose was to review the clinical and imaging findings in a series of patients with NRH and LRN in order to identify distinguishing clinical and imaging features. Materials and methods: This was a retrospective case series. The clinical and imaging features were compared in 36 patients with pathological proof of NRH and 23 patients with pathological evidence of LRN. Results: NRH and LRN have different predisposing factors and imaging findings. NRH is often associated with organ transplantation, myeloproliferative disease, or autoimmune processes. Livers with NRH typically do not have enhancing nodules; none of the present patients with NRH had enhancing liver masses. In contrast, LRN are often associated with Budd-Chiari syndrome. Enhancing liver masses were noted in 19 (83%) of the 23 patients with LRN. The p values for the comparisons were less than 0.001 for both enhancing liver masses and hepatic vein thrombosis. Conclusion: NRH and LRN can have distinct clinical presentations and imaging appearances. LRN often result in enhancing liver nodules, whereas NRH usually does not. Clinical and imaging information enables the distinction of LRN and NRH in many cases.

  11. Distinguishing clinical and imaging features of nodular regenerative hyperplasia and large regenerative nodules of the liver

    International Nuclear Information System (INIS)

    Aim: Nodular regenerative hyperplasia (NRH) and large regenerative nodules (LRN) are distinct types of hepatocellular nodules that have been confused in the radiology literature. However, distinction is critical because their clinical significance is quite different. Our purpose was to review the clinical and imaging findings in a series of patients with NRH and LRN in order to identify distinguishing clinical and imaging features. Materials and methods: This was a retrospective case series. The clinical and imaging features were compared in 36 patients with pathological proof of NRH and 23 patients with pathological evidence of LRN. Results: NRH and LRN have different predisposing factors and imaging findings. NRH is often associated with organ transplantation, myeloproliferative disease, or autoimmune processes. Livers with NRH typically do not have enhancing nodules; none of the present patients with NRH had enhancing liver masses. In contrast, LRN are often associated with Budd-Chiari syndrome. Enhancing liver masses were noted in 19 (83%) of the 23 patients with LRN. The p values for the comparisons were less than 0.001 for both enhancing liver masses and hepatic vein thrombosis. Conclusion: NRH and LRN can have distinct clinical presentations and imaging appearances. LRN often result in enhancing liver nodules, whereas NRH usually does not. Clinical and imaging information enables the distinction of LRN and NRH in many cases.

  12. MR imaging of the lungs. Clinical applications and potential research

    International Nuclear Information System (INIS)

    MR imaging of the lung is handicapped by three negative influences. First, the low proton spin density in lung tissue results in a low signal-to-noise ratio relative to the surrounding structures. Second, cardiac and respiratory motion induce artifacts that tend to obscure fine structural detail in the lung. Third, a considerable magnetic susceptibility gradient, arising from the large surface areas of air and tissue interfaces, produces a very low value for T2*. MR imaging can be used to stage the activity of interstitial lung disease and for the diagnosis of lipoid pneumonia and pulmonary infarction. In combination with MR angiography, perfusion MR imaging might eventually become a test for pulmonary embolisms. (authors)

  13. Clinics in diagnostic imaging. 141. Complete anterior cruciate ligament tear.

    Science.gov (United States)

    Lim, Hollie M Y; Peh, Wilfred C G

    2012-09-01

    A 38-year-old man presented with right knee pain and swelling following a football injury. Magnetic resonance (MR) imaging showed a complete anterior cruciate ligament (ACL) tear and lateral meniscal tears. The torn ACL was repaired with a graft obtained from the semitendinosus muscle, and the menisci were debrided. The mechanisms of injury to the ACL are varied and may be due to direct or indirect contact with the knee as well as with twisting injuries. Knowledge of the ACL's normal anatomy, together with MR imaging technique and understanding of the appearance of the lesion on MR examination, is crucial to aid in the identification of an ACL tear. Diagnosis of an ACL tear should be based on direct MR imaging signs, although indirect signs may be helpful, particularly in chronic tears. Other associated injuries to be aware of include meniscal and other ligamentous injuries. Normal ACL graft and post-ACL graft reconstruction complications are also briefly discussed. PMID:23023908

  14. Clinical application of l-123 MlBG cardiac imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Do Young [College of Medicine, Donga Univ., Busan (Korea, Republic of)

    2004-10-01

    Cardiac neurotransmission imaging allows in vivo assessment of presynaptic reuptake, neurotransmitter storage and postsynaptic receptors. Among the various neurotransmitter, I-123 MlBG is most available and relatively well-established. Metaiodobenzylguanidine (MIBG) is an analogue of the false neurotransmitter guanethidine. It is taken up to adrenergic neurons by uptake-1 mechanism as same as norepinephrine. As tagged with I-123, it can be used to image sympathetic function in various organs including heart with planar or SPECT techniques. I-123 MIBG imaging has a unique advantage to evaluate myocardial neuronal activity in which the heart has no significant structural abnormality or even no functional derangement measured with other conventional examination. In patients with cardiomyopathy and heart failure, this imaging has most sensitive technique to predict prognosis and treatment response of betablocker or ACE inhibitor. In diabetic patients, it allow very early detection of autonomic neuropathy. In patients with dangerous arrhythmia such as ventricular tachycardia or fibrillation, MIBG imaging may be only an abnormal result among various exams. In patients with ischemic heart disease, sympathetic derangement may be used as the method of risk stratification. In heart transplanted patients, sympathetic reinnervation is well evaluated. Adriamycin-induced cardiotoxicity is detected earlier than ventricular dysfunction with sympathetic dysfunction. Neurodegenerative disorder such as Parkinson's disease or dementia with Lewy bodies has also cardiac sympathetic dysfunction. Noninvasive assessment of cardiac sympathetic nerve activity with l-123 MlBG imaging may be improve understanding of the pathophysiology of cardiac disease and make a contribution to predict survival and therapy efficacy.

  15. 3-D Reconstruction From 2-D Radiographic Images and Its Application to Clinical Veterinary Medicine

    Science.gov (United States)

    Hamamoto, Kazuhiko; Sato, Motoyoshi

    3D imaging technique is very important and indispensable in diagnosis. The main stream of the technique is one in which 3D image is reconstructed from a set of slice images, such as X-ray CT and MRI. However, these systems require large space and high costs. On the other hand, a low cost and small size 3D imaging system is needed in clinical veterinary medicine, for example, in the case of diagnosis in X-ray car or pasture area. We propose a novel 3D imaging technique using 2-D X-ray radiographic images. This system can be realized by cheaper system than X-ray CT and enables to get 3D image in X-ray car or portable X-ray equipment. In this paper, a 3D visualization technique from 2-D radiographic images is proposed and several reconstructions are shown. These reconstructions are evaluated by veterinarians.

  16. IT Infrastructure to Support the Secondary Use of Routinely Acquired Clinical Imaging Data for Research

    NARCIS (Netherlands)

    K.Y.E. Leung (Esther); F. van der Lijn (Fedde); H.A. Vrooman (Henri); M.C.J.M. Sturkenboom (Miriam); W.J. Niessen (Wiro)

    2014-01-01

    textabstractWe propose an infrastructure for the automated anonymization, extraction and processing of image data stored in clinical data repositories to make routinely acquired imaging data available for research purposes. The automated system, which was tested in the context of analyzing routinely

  17. Influence of picture element size on the quality of clinical radionuclide images

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, P.F.; Chesser, R.B.; Mallard, J.R. (Aberdeen Univ. (UK). Dept. of Medical Physics)

    1982-07-01

    The effect of picture element (pixel) size on radionuclide image quality is investigated. Asked simply to state their preference for clinical images displayed with different pixel sizes, observers preferred those with the smallest pixel. Specific perceptual tasks, however, such as abnormality detection, are found to be insensitive to changes in pixel size up to a limit. Interpolation is found to have no effect on perceptual tasks, but 'random interpolation' produced a more pleasing image than simple linear interpolation.

  18. MR Imaging of Pregnancy Luteoma: a Case Report and Correlation with the Clinical Features

    OpenAIRE

    Kao, Hung-Wen; Wu, Ching-Jiunn; Chung, Kuo-Teng; Wang, Sheng-Ru; Chen, Cheng-Yu

    2005-01-01

    We report here on a 26-year-old pregnant female who developed hirsutism and virilization during her third trimester along with a significantly elevated serum testosterone level. Abdominal US and MR imaging studies were performed, and they showed unique imaging features that may suggest the diagnosis of pregnancy luteoma in the clinical context. After the delivery, the serum testosterone level continued to decrease, and it returned to normal three weeks postpartum. The follow-up imaging findin...

  19. Multi-institutional Quantitative Evaluation and Clinical Validation of Smart Probabilistic Image Contouring Engine (SPICE) Autosegmentation of Target Structures and Normal Tissues on Computer Tomography Images in the Head and Neck, Thorax, Liver, and Male Pelvis Areas

    DEFF Research Database (Denmark)

    Zhu, Mingyao; Bzdusek, Karl; Brink, Carsten;

    2013-01-01

    Clinical validation and quantitative evaluation of computed tomography (CT) image autosegmentation using Smart Probabilistic Image Contouring Engine (SPICE).......Clinical validation and quantitative evaluation of computed tomography (CT) image autosegmentation using Smart Probabilistic Image Contouring Engine (SPICE)....

  20. Optimising the diagnostic imaging process through clinical history documentation

    International Nuclear Information System (INIS)

    In the United Kingdom the 1990s were characterised by radiographer role extension including radiographic reporting and the performance of a variety of contrast examinations. In Australia where a privatised health system constrains the role of radiographers, other ways need to be found to improve professional practice and enhance patient care. One such way is for radiographers to develop knowledge and skills in clinical history taking. The paper advocates the development of a formalised approach to clinical history taking that portrays the radiographer as a professional and advocate of patient rights and welfare. The paper examines history taking approaches used by other health care professionals and proposes a clinical history template using five key areas of interview: area and type of symptoms, current history, past history, special considerations and psychosocial/occupational history. Copyright (2003) Australian Institute of Radiography

  1. Image Resolution in the Digital Era: Notion and Clinical Implications

    OpenAIRE

    Vahid Rakhshan

    2014-01-01

    Digital radiographs need additional metadata in order to be accurate when being converted to analog media. Resolution is a major reason of failures in proper printing or digitizing the images. This letter shortly explains the overlooked pitfalls of digital radiography and photography in dental practice, and briefly instructs the reader how to avoid or rectify common problems associated with resolution calibration of digital radiographs.

  2. Using functional magnetic resonance imaging to improve how we understand, teach, and assess clinical reasoning

    NARCIS (Netherlands)

    Durning, S.J.; Costanzo, M.; Artino, A.R.; Vleuten, C.P.M. van der; Beckman, T.J.; Holmboe, E.; Roy, M.J.; Schuwirth, L.

    2014-01-01

    Clinical reasoning is essential to the practice of medicine. There have been many advances in the understanding of clinical reasoning and its assessment, yet current approaches have a number of important limitations. Functional magnetic resonance imaging (fMRI) is promising because it permits invest

  3. Preclinical Evaluation of Raman Nanoparticle Biodistribution for their Potential Use in Clinical Endoscopy Imaging

    DEFF Research Database (Denmark)

    Zavaleta, Cristina L; Hartman, Keith B; Miao, Zheng;

    2011-01-01

    Raman imaging offers unsurpassed sensitivity and multiplexing capabilities. However, its limited depth of light penetration makes direct clinical translation challenging. Therefore, a more suitable way to harness its attributes in a clinical setting would be to couple Raman spectroscopy with endo...

  4. Eating epilepsy: clinical and neuro image aspects - case report

    International Nuclear Information System (INIS)

    Eating epilepsy is an uncommon form of reflex epilepsy. The authors present a case report of a patient with clinical diagnosis of eating epilepsy who was submitted to clinical tests, neuroimaging studies (MRI and SPECT) and surface EEG. Multiple intercritical EEGs showed sharp discharges in the posterior left temporal area. The MRI did not show any abnormality. The intercritical brain SPECT showed clear hypoperfusion in the posterior left temporal area; so confirming the epileptogenic focus in producing the partial complex seizures triggered by eating. (author)

  5. From clinical imaging and computational models to personalised medicine and image guided interventions.

    Science.gov (United States)

    Hawkes, David J

    2016-10-01

    This short paper describes the development of the UCL Centre for Medical Image Computing (CMIC) from 2006 to 2016, together with reference to historical developments of the Computational Imaging sciences Group (CISG) at Guy's Hospital. Key early work in automated image registration led to developments in image guided surgery and improved cancer diagnosis and therapy. The work is illustrated with examples from neurosurgery, laparoscopic liver and gastric surgery, diagnosis and treatment of prostate cancer and breast cancer, and image guided radiotherapy for lung cancer.

  6. MR imaging of pregnancy luteoma: a case report and correlation with the clinical features

    International Nuclear Information System (INIS)

    We report here on a 26-year-old pregnant female who developed hirsutism and virilization during her third trimester along with a significantly elevated serum testosterone level. Abdominal US and MR imaging studies were performed, and they showed unique imaging features that may suggest the diagnosis of pregnancy luteoma in the clinical context. After the delivery, the serum testosterone level continued to decrease, and it returned to normal three weeks postpartum. The follow-up imaging findings were closely correlated with the clinical presentation

  7. Magnetic field measurements of a clinical MR imager at 1.5 tesla

    Science.gov (United States)

    Muhech, A.; Tellez, I.; Esteva, M.; Marrufo, O.; Jimenez, L.; Vazquez, F.; Taboada, J.; Rodriguez, A. O.

    2012-10-01

    In the clinical environment is mandatory to run periodically measurements of uniformity of the magnetic field produced by the magnet to assure good image quality. The phase difference method was used to measure the magnetic field uniformity of the 1.5 T scanner of the Instituto Nacional de Neurologia y Neurocirugia MVS. The uniformity field values showed that the imager performance is reasonably good for clinical imaging. Some concern was raised since results may not be good enough for magnetic resonance spectroscopy runs.

  8. Imaging with non-FDG PET tracers: outlook for current clinical applications

    OpenAIRE

    Lopci, Egesta; Nanni, Cristina; Castellucci, Paolo; Montini, Gian Carlo; Allegri, Vincenzo; Rubello, Domenico; Chierichetti, Franca; Ambrosini, Valentina; Fanti, Stefano

    2010-01-01

    Apart from the historical and clinical relevance of positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG), various other new tracers are gaining a remarkable place in functional imaging. Their contribution to clinical decision-making is irreplaceable in several disciplines. In this brief review we aimed to describe the main non-FDG PET tracers based on their clinical relevance and application for patient care.

  9. Initial clinical testing of a multi-spectral imaging system built on a smartphone platform

    Science.gov (United States)

    Mink, Jonah W.; Wexler, Shraga; Bolton, Frank J.; Hummel, Charles; Kahn, Bruce S.; Levitz, David

    2016-03-01

    Multi-spectral imaging systems are often expensive and bulky. An innovative multi-spectral imaging system was fitted onto a mobile colposcope, an imaging system built around a smartphone in order to image the uterine cervix from outside the body. The multi-spectral mobile colposcope (MSMC) acquires images at different wavelengths. This paper presents the clinical testing of MSMC imaging (technical validation of the MSMC system is described elsewhere 1 ). Patients who were referred to colposcopy following abnormal screening test (Pap or HPV DNA test) according to the standard of care were enrolled. Multi-spectral image sets of the cervix were acquired, consisting of images from the various wavelengths. Image acquisition took 1-2 sec. Areas suspected for dysplasia under white light imaging were biopsied, according to the standard of care. Biopsied sites were recorded on a clockface map of the cervix. Following the procedure, MSMC data was processed from the sites of biopsied sites. To date, the initial histopathological results are still outstanding. Qualitatively, structures in the cervical images were sharper at lower wavelengths than higher wavelengths. Patients tolerated imaging well. The result suggests MSMC holds promise for cervical imaging.

  10. Studies on diagnosis of lung emphysema by CT image using experimental models and clinical cases

    International Nuclear Information System (INIS)

    Since the detailed report between the degree of functional disorder in lung emphysema and the analysis of CT image is quite unknown, the present study was attempted to produce the experimental model of lung emphysema with various stages by the administration of papain to the focal lobe in canine lung. Using this model or clinical lung emphysema, the relationship between the degree of destruction of alveolar walls, clinical pulmonary functions and CT images was investigated. CT scan was performed at the level of 50% vital capacity in both experimental models and clinical subjects by using spirometric gating CT. CT density histogram was obtained from CT image which was produced by using the developed software for this purpose. Densitometric parameters, such as mean CT value, %LAA, the peak in the histogram and 5% tile were selected from CT image. Papain solution of 5 mg/kg body weight was cumulatively administered to the left lower lobe in canine lung, resulting in the destruction of lung alveolar walls in parallel to the increasing dosage of papain. There was a significant correlation between not only the increasing dosage of papain, but also %FEV 1.0 and CT densitometric parameters, indicating that the histological changes of alveolar walls and the lung function in lung emphysema could be estimated by analysis of CT image. These experimental and clinical studies suggest that the analysis of CT image can reflect the pathophysiological changes in the lung and be useful for precise clinical diagnosis of lung emphysema. (author)

  11. Studies on diagnosis of lung emphysema by CT image using experimental models and clinical cases

    Energy Technology Data Exchange (ETDEWEB)

    Nakatani, Seiki [Wakayama Medical Coll. (Japan)

    1998-01-01

    Since the detailed report between the degree of functional disorder in lung emphysema and the analysis of CT image is quite unknown, the present study was attempted to produce the experimental model of lung emphysema with various stages by the administration of papain to the focal lobe in canine lung. Using this model or clinical lung emphysema, the relationship between the degree of destruction of alveolar walls, clinical pulmonary functions and CT images was investigated. CT scan was performed at the level of 50% vital capacity in both experimental models and clinical subjects by using spirometric gating CT. CT density histogram was obtained from CT image which was produced by using the developed software for this purpose. Densitometric parameters, such as mean CT value, %LAA, the peak in the histogram and 5% tile were selected from CT image. Papain solution of 5 mg/kg body weight was cumulatively administered to the left lower lobe in canine lung, resulting in the destruction of lung alveolar walls in parallel to the increasing dosage of papain. There was a significant correlation between not only the increasing dosage of papain, but also %FEV 1.0 and CT densitometric parameters, indicating that the histological changes of alveolar walls and the lung function in lung emphysema could be estimated by analysis of CT image. These experimental and clinical studies suggest that the analysis of CT image can reflect the pathophysiological changes in the lung and be useful for precise clinical diagnosis of lung emphysema. (author)

  12. NCI Workshop Report: Clinical and Computational Requirements for Correlating Imaging Phenotypes with Genomics Signatures

    Directory of Open Access Journals (Sweden)

    Rivka Colen

    2014-10-01

    Full Text Available The National Cancer Institute (NCI Cancer Imaging Program organized two related workshops on June 26–27, 2013, entitled “Correlating Imaging Phenotypes with Genomics Signatures Research” and “Scalable Computational Resources as Required for Imaging-Genomics Decision Support Systems.” The first workshop focused on clinical and scientific requirements, exploring our knowledge of phenotypic characteristics of cancer biological properties to determine whether the field is sufficiently advanced to correlate with imaging phenotypes that underpin genomics and clinical outcomes, and exploring new scientific methods to extract phenotypic features from medical images and relate them to genomics analyses. The second workshop focused on computational methods that explore informatics and computational requirements to extract phenotypic features from medical images and relate them to genomics analyses and improve the accessibility and speed of dissemination of existing NIH resources. These workshops linked clinical and scientific requirements of currently known phenotypic and genotypic cancer biology characteristics with imaging phenotypes that underpin genomics and clinical outcomes. The group generated a set of recommendations to NCI leadership and the research community that encourage and support development of the emerging radiogenomics research field to address short-and longer-term goals in cancer research.

  13. Moxifloxacin: Clinically compatible contrast agent for multiphoton imaging

    OpenAIRE

    Taejun Wang; Won Hyuk Jang; Seunghun Lee; Yoon, Calvin J.; Jun Ho Lee; Bumju Kim; Sekyu Hwang; Chun-Pyo Hong; Yeoreum Yoon; Gilgu Lee; Viet-Hoan Le; Seoyeon Bok; G-One Ahn; Jaewook Lee; Yong Song Gho

    2016-01-01

    Multiphoton microscopy (MPM) is a nonlinear fluorescence microscopic technique widely used for cellular imaging of thick tissues and live animals in biological studies. However, MPM application to human tissues is limited by weak endogenous fluorescence in tissue and cytotoxicity of exogenous probes. Herein, we describe the applications of moxifloxacin, an FDA-approved antibiotic, as a cell-labeling agent for MPM. Moxifloxacin has bright intrinsic multiphoton fluorescence, good tissue penetra...

  14. Image Resolution in the Digital Era: Notion and Clinical Implications

    Directory of Open Access Journals (Sweden)

    Vahid Rakhshan

    2014-05-01

    Full Text Available Digital radiographs need additional metadata in order to be accurate when being converted to analog media. Resolution is a major reason of failures in proper printing or digitizing the images. This letter shortly explains the overlooked pitfalls of digital radiography and photography in dental practice, and briefly instructs the reader how to avoid or rectify common problems associated with resolution calibration of digital radiographs.

  15. Image Resolution in the Digital Era: Notion and Clinical Implications

    Directory of Open Access Journals (Sweden)

    Vahid Rakhshan

    2014-12-01

    Full Text Available Digital radiographs need additional metadata in order to be accurate when being converted to analog media. Resolution is a major reason of failures in proper printing or digitizing the images. This letter shortly explains the overlooked pitfalls of digital radiography and photography in dental practice, and briefly instructs the reader how to avoid or rectify common problems associated with resolution calibration of digital radiographs.

  16. Image Resolution in the Digital Era: Notion and Clinical Implications

    Science.gov (United States)

    Rakhshan, Vahid

    2014-01-01

    Digital radiographs need additional metadata in order to be accurate when being converted to analog media. Resolution is a major reason of failures in proper printing or digitizing the images. This letter shortly explains the overlooked pitfalls of digital radiography and photography in dental practice, and briefly instructs the reader how to avoid or rectify common problems associated with resolution calibration of digital radiographs. PMID:25469352

  17. Avulsion Fractures of the Knee: Imaging Findings and Clinical Significance

    Directory of Open Access Journals (Sweden)

    Babak Sanei

    2010-05-01

    Full Text Available The knee is an intricate joint with numerous tendinous, ligamentous, and meniscal attachments, which make it particularly vulnerable to complex injuries after trauma. A variety of avulsion fractures of the knee can occur, including Segond and reverse Segond fractures; avulsions of the anterior and posterior cruciate ligaments; arcuate complex avulsion; iliotibial band avulsion; avulsions of the biceps femoris, semimembranous, and quadriceps tendons; Sinding-Larsen-Johansson syndrome; and Osgood- Schlatter disease. These fractures often have a subtle appearance at conventional radiography, which is typically the first imaging modality performed in these cases. Advanced imaging modalities, particularly magnetic resonance imaging, are helpful and can provide valuable additional information for adequately defining the extent of damage. The onus is on the radiologist to identify the pattern of injury and to understand the substantial underlying damage that it frequently represents. Conveying this information to the referring clinician is crucial and represents the first step toward additional evaluation and probable orthopedic referral. By recognizing the significance of these injuries at initial presentation, radiologists can facilitate appropriate patient work-up and prevent the chronic morbidity associated with delayed treatment.

  18. Technetium-99m NGA functional hepatic imaging: preliminary clinical experience

    International Nuclear Information System (INIS)

    Technetium-99m galactosyl-neoglycoalbumin ( [Tc]NGA) is a radiolabeled ligand to hepatic binding protein, a receptor which resides at the plasma membrane of hepatocytes. This receptor-binding radiopharmaceutical and its kinetic model provide a noninvasive method for the assessment of liver function. Eighteen patients were studied: seven with hepatoma, eight with liver metastases, four with cirrhosis, and one patient with acute fulminant non-A, non-B hepatitis. Technetium-99m NGA liver imaging provided anatomic information of diagnostic quality comparable to that obtained with other routine imaging modalities, including computed tomography, angiography, ultrasound, and [Tc]sulfur colloid scintigraphy. Kinetic modeling of dynamic [Tc]NGA data produced estimates of standardized hepatic blood flow, Q (hepatic blood flow divided by total blood volume), and hepatic binding protein concentration, [HBP]. Significant rank correlation was obtained between [HBP] estimates and CTC scores. This correlation supports the hypothesis that [HBP] is a measure of functional hepatocyte mass. The combination of decreased Q and markedly reduced [HBP] may have prognostic significance; all three patients with this combination died of hepatic failure within 6 wk of imaging

  19. Interconnecting smartphone, image analysis server, and case report forms in clinical trials for automatic skin lesion tracking in clinical trials

    Science.gov (United States)

    Haak, Daniel; Doma, Aliaa; Gombert, Alexander; Deserno, Thomas M.

    2016-03-01

    Today, subject's medical data in controlled clinical trials is captured digitally in electronic case report forms (eCRFs). However, eCRFs only insufficiently support integration of subject's image data, although medical imaging is looming large in studies today. For bed-side image integration, we present a mobile application (App) that utilizes the smartphone-integrated camera. To ensure high image quality with this inexpensive consumer hardware, color reference cards are placed in the camera's field of view next to the lesion. The cards are used for automatic calibration of geometry, color, and contrast. In addition, a personalized code is read from the cards that allows subject identification. For data integration, the App is connected to an communication and image analysis server that also holds the code-study-subject relation. In a second system interconnection, web services are used to connect the smartphone with OpenClinica, an open-source, Food and Drug Administration (FDA)-approved electronic data capture (EDC) system in clinical trials. Once the photographs have been securely stored on the server, they are released automatically from the mobile device. The workflow of the system is demonstrated by an ongoing clinical trial, in which photographic documentation is frequently performed to measure the effect of wound incision management systems. All 205 images, which have been collected in the study so far, have been correctly identified and successfully integrated into the corresponding subject's eCRF. Using this system, manual steps for the study personnel are reduced, and, therefore, errors, latency and costs decreased. Our approach also increases data security and privacy.

  20. Detection of Artifacts and Its Effects in the Clinical Evaluation of Diagnostic and Therapy CT Images

    Directory of Open Access Journals (Sweden)

    Sadiq R Malik

    2014-01-01

    Full Text Available Importance of imaging in all clinical or medical research, and especially, of Computerized Axial Tomography (CAT scan, has demonstrated a unique place in diagnostic or radiation therapy. Two-dimensional images of internal structures of the body are examined and reported. This process of imaging, any anatomical location, viz. head and neck, thorax, pelvis, etc. takes about 30 seconds to perform with a minimal dose of less than 1.6- 2.0 mGy. The images are constructed by the hardware with software algorithm, using the attenuation and absorption of X rays of tissues, of varying electron densities of the anatomical structures. Sometimes a contrast dye is injected to a patient intravenously, rectally or orally, to make hollow or fluid-filled structures such as blood vessels more visible. Radiologists and radiation oncologists are confronted with a task to delineate the information of the CT images to a meaningful diagnosis. The images are, therefore, valuable for diagnostic reports, some of these may relate to cancerous tumors and tissues. Cancer treatment, radiation therapy or else, from such observations may start. But an artifact and distortion on such images will contribute to erroneous and/or unusable interpretations in offering a clinical report to provide wrong clinical decisions. The implications of the presence of distortion in CT images is, for a patient, described here so as to instruct the experts, in medical and clinical fields, to rectify the situation in acquiring a sharp and flawless image or in reaching the correct clinical goal.

  1. Proton spectroscopy of the brain in HIV infection: correlation with clinical, immunologic, and MR imaging findings.

    Science.gov (United States)

    Chong, W K; Sweeney, B; Wilkinson, I D; Paley, M; Hall-Craggs, M A; Kendall, B E; Shepard, J K; Beecham, M; Miller, R F; Weller, I V

    1993-07-01

    Abnormalities at cerebral proton spectroscopy occur in patients with the acquired immunodeficiency syndrome (AIDS). N-acetyl aspartate (NAA) is believed to be a neuronal marker, and neuronal loss is thought to underlie the human immunodeficiency virus (HIV)-associated cognitive/motor complex. The proton spectra in 103 HIV-seropositive patients and 23 control subjects were compared and correlated with clinical, immunologic, and radiologic measures of HIV infection. Significant (P suppression and neurologic signs. Significant increases in the Cho/Cr ratios were seen in patients with low CD4 lymphocyte counts and abnormal magnetic resonance (MR) images. Reduced NAA ratios correlated with diffuse but not focal MR imaging abnormalities. Combined MR imaging and spectroscopy provides closer relationships to clinical and immunologic measures of disease than either modality alone. Spectroscopy is an adjunct to MR imaging and augments the value of an MR imaging study. PMID:8099750

  2. Clinical use of gadobutrol for contrast-enhanced magnetic resonance imaging of neurological diseases

    Directory of Open Access Journals (Sweden)

    Cheng KT

    2012-02-01

    Full Text Available Kenneth T Cheng1, Hannah Y Cheng2, Kam Leung31Department of Radiology and Imaging Sciences, Clinical Center, National Institutes of Health, Bethesda, MD, USA; 2Freelance Technical Writer, New Orleans, LA, USA; 3National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD, USAAbstract: Contrast-enhanced magnetic resonance imaging (CE-MRI is an important clinical tool for diagnosing neurological diseases. The appropriate use of a suitable MRI contrast agent or contrast pharmaceutical is essential for CE-MRI to produce desirable diagnostic images. Currently, there are seven contrast agents (CAs or pharmaceuticals approved for clinical imaging of the central nervous system (CNS in the US, Europe, or Japan. All of the clinically approved CAs are water-soluble gadolinium-based contrast agents (GBCAs which do not penetrate the CNS blood–brain barrier (BBB. These agents are used for imaging CNS areas without a BBB, or various pathologies, such as tumors and infection that break down the BBB and allow CAs to enter into the surrounding parenchyma. Clinically, GBCAs are most useful for detecting primary and secondary cerebral neoplastic lesions. Among these CNS GBCAs, gadobutrol (Gd-BT-DO3A, Gadovist™ is a neutral, nonionic, macrocyclic compound that showed promising results from clinical trials of CNS imaging. In comparison with other GBCAs, Gd-BT-DO3A has relatively high in vitro kinetic stability and r1 relaxivity. Gd-BT-DO3A has been recently approved by the US Food and Drug Administration (FDA in 2011 for CNS imaging. A review of available literature shows that Gd-BT-DO3A exhibits similar safety and clinical efficacy profiles to other GBCAs. Gd-BT-DO3A has the distinguishing feature that it is the only clinical agent commercially available in a formulation of 1.0 M concentration with a relatively higher in vitro T1 shortening per unit volume than other clinical GBCAs which are only

  3. Comparison of ultrasound B-mode, strain imaging, acoustic radiation force impulse displacement and shear wave velocity imaging using real time clinical breast images

    Science.gov (United States)

    Manickam, Kavitha; Machireddy, Ramasubba Reddy; Raghavan, Bagyam

    2016-04-01

    It has been observed that many pathological process increase the elastic modulus of soft tissue compared to normal. In order to image tissue stiffness using ultrasound, a mechanical compression is applied to tissues of interest and local tissue deformation is measured. Based on the mechanical excitation, ultrasound stiffness imaging methods are classified as compression or strain imaging which is based on external compression and Acoustic Radiation Force Impulse (ARFI) imaging which is based on force generated by focused ultrasound. When ultrasound is focused on tissue, shear wave is generated in lateral direction and shear wave velocity is proportional to stiffness of tissues. The work presented in this paper investigates strain elastography and ARFI imaging in clinical cancer diagnostics using real time patient data. Ultrasound B-mode imaging, strain imaging, ARFI displacement and ARFI shear wave velocity imaging were conducted on 50 patients (31 Benign and 23 malignant categories) using Siemens S2000 machine. True modulus contrast values were calculated from the measured shear wave velocities. For ultrasound B-mode, ARFI displacement imaging and strain imaging, observed image contrast and Contrast to Noise Ratio were calculated for benign and malignant cancers. Observed contrast values were compared based on the true modulus contrast values calculated from shear wave velocity imaging. In addition to that, student unpaired t-test was conducted for all the four techniques and box plots are presented. Results show that, strain imaging is better for malignant cancers whereas ARFI imaging is superior than strain imaging and B-mode for benign lesions representations.

  4. Basic research and clinical application of optical molecular imaging in breast cancer

    International Nuclear Information System (INIS)

    As a rapidly developing biomedical imaging technology,in vivo optical molecular imaging has been widely applied in various research fields owing to its unique real-time, quantitative and noninvasive characteristics. The applications of in vivo optical imaging technology in the basic and clinical research of breast cancer were reviewed, including detection of distant metastasis,tumor apoptosis, cell cycle, hypoxia and angiogenesis, ER-mediated molecular pathway, breast cancer stem cells, early diagnosis, sentinel node biopsy, evaluation of drug efficacy and detection of human epidermal growth factor receptor-2 (HER-2) expression. They all seem to have a promising potential in in vivo optical molecular imaging. (authors)

  5. Handbook of nuclear medicine and molecular imaging principles and clinical applications

    CERN Document Server

    Kim, Edmund E; Tateishi, Ukihide; Baum, Richard P

    2012-01-01

    This handbook will provide updated information on nuclear medicine and molecular imaging techniques as well as its clinical applications, including radionuclide therapy, to trainees and practitioners of nuclear medicine, radiology and general medicine. Updated information on nuclear medicine and molecular imaging are vitally important and useful to both trainees and existing practitioners. Imaging techniques and agents are advancing and changing so rapidly that concise and pertinent information are absolutely necessary and helpful. It is hoped that this handbook will help readers be better equipped for the utilization of new imaging methods and treatments using radiopharmaceuticals.

  6. Present status of PACS at Kyoto University Hospital: image workstation for clinical education

    Science.gov (United States)

    Minato, Kotaro; Komori, Masaru; Nakano, Yoshihisa; Okajima, Kaoru; Kimura, Ishu; Takahashi, Takashi; Konishi, Junji; Abe, Mituyuki; Gotoh, Yoshihiro; Sato, Kazuhiro

    1990-08-01

    The PAC system: KIDS (Kyoto University Hospital Image Database and Communication System) has been expanded to include several major digital imaging modalities such as X-ray CT, MRI, DSA and CR. The fiber optic high-speed local area network and the workstation with quick image handling are newly designed. The system (new KIDS) is intended to achieve a film-less environment in the department of radiology and to evaluate the feasibility of a hospital-wide PAC system. The present status of the system at the end of 1989 including a image workstation installed in a lecture hall for clinical education is described.

  7. Imaging diagnosis in relapsing polychondritis and correlation with clinical and serological data

    Energy Technology Data Exchange (ETDEWEB)

    Thaiss, W.M.; Nikolaou, K.; Horger, M. [Eberhard Karls University, Department of Radiology, Diagnostic and Interventional Radiology, Tuebingen (Germany); Spengler, W.; Xenitidis, T.; Henes, J. [Eberhard Karls University, Department of Internal Medicine II, Tuebingen (Germany); Spira, D. [Eberhard Karls University, Department of Radiology, Diagnostic and Interventional Radiology, Tuebingen (Germany); University Medical Center Heidelberg, Diagnostic and Interventional Radiology, Heidelberg (Germany)

    2016-03-15

    We hypothesize that imaging findings from CT and MRI correlate better with clinical markers for assessment of disease activity in patients with the rare relapsing polychondritis (RPC) than with serological inflammatory markers. Retrospective database search at our institution identified 28 patients (13 females; age 49.0 years ± 15.0 SD) with RP between September 2004 and March 2014. Institutional review board approval was obtained for this retrospective data analysis. All patients had clinically proven RPC with at least two episodes of active disease. Of those, 18 patients were examined with CT- and MRI and presented all morphologic features of RPC like bronchial/laryngeal/auricular cartilage thickness, contrast enhancement, increased T2-signal intensity. Imaging data was subsequently correlated with corresponding clinical symptoms like fever, dyspnea, stridor, uveitis, pain, hearing impairment as well as with acute-phase-inflammatory parameters like C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). The clinical parameters were in good agreement with imaging findings and clinical symptoms such as tracheal wall thickening and dyspnea (r =0.65 p = 0.05), joint synovitis on MRI and a higher McAdam score (r = 0.84 p < 0.001). No correlations were found between inflammatory laboratory markers, imaging findings and clinical features. Imaging diagnosis in RPC using CT and/or MRI delivers information about the degree of disease activity that correlates better with clinical features than unspecific inflammatory laboratory markers. Additionally, clinically unapparent cartilage involvement can be assessed adding value to the clinical diagnosis and therapy planning in this rare disease. (orig.)

  8. Imaging diagnosis in relapsing polychondritis and correlation with clinical and serological data

    International Nuclear Information System (INIS)

    We hypothesize that imaging findings from CT and MRI correlate better with clinical markers for assessment of disease activity in patients with the rare relapsing polychondritis (RPC) than with serological inflammatory markers. Retrospective database search at our institution identified 28 patients (13 females; age 49.0 years ± 15.0 SD) with RP between September 2004 and March 2014. Institutional review board approval was obtained for this retrospective data analysis. All patients had clinically proven RPC with at least two episodes of active disease. Of those, 18 patients were examined with CT- and MRI and presented all morphologic features of RPC like bronchial/laryngeal/auricular cartilage thickness, contrast enhancement, increased T2-signal intensity. Imaging data was subsequently correlated with corresponding clinical symptoms like fever, dyspnea, stridor, uveitis, pain, hearing impairment as well as with acute-phase-inflammatory parameters like C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR). The clinical parameters were in good agreement with imaging findings and clinical symptoms such as tracheal wall thickening and dyspnea (r =0.65 p = 0.05), joint synovitis on MRI and a higher McAdam score (r = 0.84 p < 0.001). No correlations were found between inflammatory laboratory markers, imaging findings and clinical features. Imaging diagnosis in RPC using CT and/or MRI delivers information about the degree of disease activity that correlates better with clinical features than unspecific inflammatory laboratory markers. Additionally, clinically unapparent cartilage involvement can be assessed adding value to the clinical diagnosis and therapy planning in this rare disease. (orig.)

  9. Clinical assessment of chest pain and guidelines for imaging

    Energy Technology Data Exchange (ETDEWEB)

    Gruettner, J., E-mail: joachim.gruettner@umm.de [1st Department of Medicine (Cardiology), University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim (Germany); Henzler, T. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim (Germany); Sueselbeck, T. [1st Department of Medicine (Cardiology), University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim (Germany); Fink, C. [Institute of Clinical Radiology and Nuclear Medicine, University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim (Germany); Borggrefe, M.; Walter, T. [1st Department of Medicine (Cardiology), University Medical Center Mannheim, Medical Faculty Mannheim, University of Heidelberg, Mannheim (Germany)

    2012-12-15

    For many emergency facilities, risk assessment of patients with diffuse chest pain still poses a major challenge. In their currently valid recommendations, the international cardiological societies have defined a standardized assessment of the prognostically relevant cardiac risk criteria. Here the classic sequence of basic cardiac diagnostics including case history (cardiac risk factors), physical examination (haemodynamic and respiratory vital parameters), ECG (ST segment analysis) and laboratory risk markers (troponin levels) is paramount. The focus is, on the one hand, on timely indication for percutaneous catheterization, especially in patients at high cardiac risk with or without ST-segment elevation in the ECG, and, on the other hand, on the possibility of safely discharging patients with intermediate or low cardiac risk after non-invasive exclusion of a coronary syndrome. For patients in the intermediate or low risk group, physical or pharmacological stress testing in combination with scintigraphy, echocardiography or magnetic resonance imaging is recommended in addition to basic diagnostics. Moreover, the importance of non-invasive coronary imaging, primarily cardiac CT angiography (CCTA), is increasing. Current data show that in intermediate or low risk patients this method is suitable to reliably rule out coronary heart disease. In addition, attention is paid to the major differential diagnoses of acute coronary syndrome, particularly pulmonary embolism and aortic dissection. Here the diagnostic method of choice is thoracic CT, possibly also in combination with CCTA aiming at a triple rule-out.

  10. Clinical assessment of chest pain and guidelines for imaging

    International Nuclear Information System (INIS)

    For many emergency facilities, risk assessment of patients with diffuse chest pain still poses a major challenge. In their currently valid recommendations, the international cardiological societies have defined a standardized assessment of the prognostically relevant cardiac risk criteria. Here the classic sequence of basic cardiac diagnostics including case history (cardiac risk factors), physical examination (haemodynamic and respiratory vital parameters), ECG (ST segment analysis) and laboratory risk markers (troponin levels) is paramount. The focus is, on the one hand, on timely indication for percutaneous catheterization, especially in patients at high cardiac risk with or without ST-segment elevation in the ECG, and, on the other hand, on the possibility of safely discharging patients with intermediate or low cardiac risk after non-invasive exclusion of a coronary syndrome. For patients in the intermediate or low risk group, physical or pharmacological stress testing in combination with scintigraphy, echocardiography or magnetic resonance imaging is recommended in addition to basic diagnostics. Moreover, the importance of non-invasive coronary imaging, primarily cardiac CT angiography (CCTA), is increasing. Current data show that in intermediate or low risk patients this method is suitable to reliably rule out coronary heart disease. In addition, attention is paid to the major differential diagnoses of acute coronary syndrome, particularly pulmonary embolism and aortic dissection. Here the diagnostic method of choice is thoracic CT, possibly also in combination with CCTA aiming at a triple rule-out.

  11. Wireless remote control clinical image workflow: utilizing a PDA for offsite distribution

    Science.gov (United States)

    Liu, Brent J.; Documet, Luis; Documet, Jorge; Huang, H. K.; Muldoon, Jean

    2004-04-01

    Last year we presented in RSNA an application to perform wireless remote control of PACS image distribution utilizing a handheld device such as a Personal Digital Assistant (PDA). This paper describes the clinical experiences including workflow scenarios of implementing the PDA application to route exams from the clinical PACS archive server to various locations for offsite distribution of clinical PACS exams. By utilizing this remote control application, radiologists can manage image workflow distribution with a single wireless handheld device without impacting their clinical workflow on diagnostic PACS workstations. A PDA application was designed and developed to perform DICOM Query and C-Move requests by a physician from a clinical PACS Archive to a CD-burning device for automatic burning of PACS data for the distribution to offsite. In addition, it was also used for convenient routing of historical PACS exams to the local web server, local workstations, and teleradiology systems. The application was evaluated by radiologists as well as other clinical staff who need to distribute PACS exams to offsite referring physician"s offices and offsite radiologists. An application for image workflow management utilizing wireless technology was implemented in a clinical environment and evaluated. A PDA application was successfully utilized to perform DICOM Query and C-Move requests from the clinical PACS archive to various offsite exam distribution devices. Clinical staff can utilize the PDA to manage image workflow and PACS exam distribution conveniently for offsite consultations by referring physicians and radiologists. This solution allows the radiologist to expand their effectiveness in health care delivery both within the radiology department as well as offisite by improving their clinical workflow.

  12. Highly accelerated cardiovascular MR imaging using many channel technology: concepts and clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Niendorf, Thoralf [RWTH Aachen, University Hospital, Department of Diagnostic Radiology, Aachen (Germany); Sodickson, Daniel K. [New York University School of Medicine, Department of Radiology, Center for Biomedical Imaging, New York, NY (United States)

    2008-01-15

    Cardiovascular magnetic resonance imaging (CVMRI) is of proven clinical value in the non-invasive imaging of cardiovascular diseases. CVMRI requires rapid image acquisition, but acquisition speed is fundamentally limited in conventional MRI. Parallel imaging provides a means for increasing acquisition speed and efficiency. However, signal-to-noise (SNR) limitations and the limited number of receiver channels available on most MR systems have in the past imposed practical constraints, which dictated the use of moderate accelerations in CVMRI. High levels of acceleration, which were unattainable previously, have become possible with many-receiver MR systems and many-element, cardiac-optimized RF-coil arrays. The resulting imaging speed improvements can be exploited in a number of ways, ranging from enhancement of spatial and temporal resolution to efficient whole heart coverage to streamlining of CVMRI work flow. In this review, examples of these strategies are provided, following an outline of the fundamentals of the highly accelerated imaging approaches employed in CVMRI. Topics discussed include basic principles of parallel imaging; key requirements for MR systems and RF-coil design; practical considerations of SNR management, supported by multi-dimensional accelerations, 3D noise averaging and high field imaging; highly accelerated clinical state-of-the art cardiovascular imaging applications spanning the range from SNR-rich to SNR-limited; and current trends and future directions. (orig.)

  13. Real-time interactive MR imaging system. Sequence optimization, and basic and clinical evaluations

    International Nuclear Information System (INIS)

    A real-time interactive MR imaging system (real-time MRI) is an MR scanner which has a fast image updating cycle and the ability to freely change slice orientation, just like an ultrasound imaging system. Recently, such a system has been developed and installed on a clinical 1.5-Tesla system. The purpose of this study was to optimize the pulse sequences for clinical use and to evaluate the clinical usefulness and basic functionality of real-time MRI. For T1-weighted imaging, FLASH (fast low angle shot) can be selected, and up to 5 frames per second can be acquired depending on the matrix size. For T2-weighted imaging, true FISP (fast imaging with steady-state precession) can be selected, and up to 4 frames per second can be acquired. Maximum C/N between liver and spleen was obtained at a flip angle of 20 degrees on FLASH. Maximum C/N between cardiac cavity and wall was obtained at a flip angle of 60 degrees on true FISP. Localization of the right and left coronary arteries could be performed within 30 seconds in three volunteers. Although the present real-time MRI system has drawbacks such as low spatial resolution and relatively low contrast resolution, we expect real-time MRI to be one of the most important tools for future clinical MRI. (author)

  14. Clinical PET/CT Atlas: A Casebook of Imaging in Oncology

    International Nuclear Information System (INIS)

    Integrated positron emission tomography/computed tomography (PET/CT) has evolved since its introduction into the commercial market more than a decade ago. It is now a key procedure, particularly in oncological imaging. Over the last years in routine clinical service, PET/CT has had a significant impact on diagnosis, treatment planning, staging, therapy, and monitoring of treatment response and has therefore played an important role in the care of cancer patients. The high sensitivity from the PET component and the specificity of the CT component give this hybrid imaging modality the unique characteristics that make PET/CT, even after over 10 years of clinical use, one of the fastest growing imaging modalities worldwide. This publication combines over 90 comprehensive cases covering all major indications of fluorodeoxyglucose (18F-FDG)-PET/CT as well as some cases of clinically relevant special tracers. The cases provide an overview of what the specific disease can look like in PET/CT, the typical pattern of the disease’s spread as well as likely pitfalls and teaching points. This PET/CT Atlas will allow professionals interested in PET/CT imaging to embrace the variety of oncological imaging by providing clinically relevant teaching files on the effectiveness and diagnostic quality of FDG-PET/CT imaging in routine applications

  15. [A future image of clinical inspection from health economics].

    Science.gov (United States)

    Kakihara, Hiroaki

    2006-06-01

    Do you let medical costs increase in proportion to the growth rate of GDP? A way of thinking of the Council on Economic and Fiscal Policy. Should we exclude public medical insurance? It is not a problem, it is an absolute sum if you are effective. If there is no insurance, and individuals pay the total amount, there is no problem, but it is impossible. Economic development will cease if there is no insurance. As medical personnel, to offer good medical care with an appropriate cost. An appeal to the nation is necessary. Economic technical evaluation to identify a cheap method for each clinical inspection. Does medical insurance have a deficit? I. Japanese Health insurance system. (1) Health insurance union. When you look at the contribution money, it is originally 2,479,800,000,000 yen, with premium income and a profit of 45%. (2) Government management health insurance. When you look at the contribution money, it is originally 2,163,300,000,000 yen, with premium income and a profit of 36%. (1) + (2) Employed insurance meter. (3) Mutual aid. (4) National Health Insurance. II. A clinical economic method. III. Expense of medical care and its effect. A. Expense. B. A medical economic technical evaluation method. 1. Cost-effectiveness analysis CEA. 2. Cost utility analysis CUA. 3. Cost-benefit analysis CBA. 4. Expense minimization analysis. PMID:16872018

  16. Development and clinical translation of OTIS: a wide-field OCT imaging device for ex-vivo tissue characterization

    Science.gov (United States)

    Munro, Elizabeth A.; Rempel, David; Danner, Christine; Atchia, Yaaseen; Valic, Michael S.; Berkeley, Andrew; Davoudi, Bahar; Magnin, Paul A.; Akens, Margarete; Done, Susan J.; Kulkarni, Supriya; Leong, Wey-Liang; Wilson, Brian C.

    2016-03-01

    We have developed an automated, wide-field optical coherence tomography (OCT)-based imaging device (OTISTM Perimeter Medical Imaging) for peri-operative, ex-vivo tissue imaging. This device features automated image acquisition, enabling rapid capture of high-resolution (15 μm) OCT images from samples up to 10 cm in diameter. We report on the iterative progression of device development from phantom and pre-clinical (tumor xenograft) models through to initial clinical results. We discuss the challenges associated with proving a novel imaging technology against the clinical "gold standard" of conventional post-operative pathology.

  17. Clinical and Imaging Findings in an Infant With Zika Embryopathy.

    Science.gov (United States)

    Culjat, Marko; Darling, Stephen E; Nerurkar, Vivek R; Ching, Natascha; Kumar, Mukesh; Min, Sarah K; Wong, Rupa; Grant, Leon; Melish, Marian E

    2016-09-15

    Recent Zika virus (ZIKV) outbreaks have been associated with an increased incidence of neonatal microcephaly. Subsequently, tropism for the brain was established in human fetal brain tissue. We present the first congenital ZIKV infection in the United States, confirmed by high ZIKV immunoglobulin M antibody titers in serum and cerebrospinal fluid. The phenotypic characteristics of the patient fall within fetal brain disruption sequence, suggesting impaired brain development in the second half of gestation. Brain imaging revealed an almost agyric brain with diffuse parenchymal calcifications, hydrocephalus ex vacuo, and cerebellar hypoplasia. Ophthalmologic examination revealed macular pigment stippling and optic nerve atrophy. Liver, lungs, heart, and bone marrow were not affected. The patient had progressive neurologic deterioration in the first month of life. The discovery of ZIKV infection in human fetal brain tissue along with serologic confirmation proves the vertical transmission of ZIKV. Therefore, ZIKV has joined the group of congenital infections. PMID:27193747

  18. Clinical image: Hydatid disease of the chest wall

    Energy Technology Data Exchange (ETDEWEB)

    Graham, R.J.; Berlin, J.W.; Ghahremani, G.G. [Northwestern Univ., Evanston, IL (United States)

    1996-05-01

    Hydatid disease is rarely encountered among the population of the United States, but it affects several million people in sheep-raising regions of the world. Human infestation with Echinococcus granulosus begins following ingestion of its ova, which are excreted into the contaminated water during the usual dog-sheep cycle. Hydatid cysts will then develop most frequently in the liver (75% of cases) and lungs (15%) of the human host. Skeletal involvement has been reported to occur in only 0.5-4.0% of patients in the endemic areas. Because of the rarity and perplexing imaging features of hydatid disease involving the chest wall, we wish herein to present a case evaluated recently at our institution. 5 refs., 1 fig.

  19. TH-A-18A-01: Innovation in Clinical Breast Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Liu, B [Massachusetts General Hospital, Boston, MA (United States); Yang, K [University of Oklahoma, Oklahomoa City, OK (United States); Yaffe, M [University Toronto, Toronto, ON (Canada); Chen, J [GE/U-Systems, Sunnyvale, CA (United States)

    2014-06-15

    Several novel modalities have been or are on the verge of being introduced into the breast imaging clinic. These include tomosynthesis imaging, dedicated breast CT, contrast-enhanced digital mammography, and automated breast ultrasound, all of which are covered in this course. Tomosynthesis and dedicated breast CT address the problem of tissue superimposition that limits mammography screening performance, by improved or full resolution of the 3D breast morphology. Contrast-enhanced digital mammography provides functional information that allows for visualization of tumor angiogenesis. 3D breast ultrasound has high sensitivity for tumor detection in dense breasts, but the imaging exam was traditionally performed by radiologists. In automated breast ultrasound, the scan is performed in an automated fashion, making for a more practical imaging tool, that is now used as an adjunct to digital mammography in breast cancer screening. This course will provide medical physicists with an in-depth understanding of the imaging physics of each of these four novel imaging techniques, as well as the rationale and implementation of QC procedures. Further, basic clinical applications and work flow issues will be discussed. Learning Objectives: To be able to describe the underlying physical and physiological principles of each imaging technique, and to understand the corresponding imaging acquisition process. To be able to describe the critical system components and their performance requirements. To understand the rationale and implementation of quality control procedures, as well as regulatory requirements for systems with FDA approval. To learn about clinical applications and understand risks and benefits/strength and weakness of each modality in terms of clinical breast imaging.

  20. Clinical application of Hawkeye VG SPECT/CT imaging in the bleeding position of lower gastrointestinal

    International Nuclear Information System (INIS)

    Objective: To evaluate the clinical application of Hawkeye VG SPECT/CT imaging on diagnosing and locating lower gastrointestinal bleeding using in vivo labeling 99Tcm-RBC. Methods: Fifty-six patients (42 males, 14 females, age ranging from 10 to 76 years) who had definite lower gastrointestinal bleeding were studied retrospectively. All patients had intravenous injection with 370 MBq 99Tcm-RBC and then underwent planar, SPECT, and CT imaging respectively in the abdomen before exploratory laparotomy. Images from SPECT and CT were fused thereafter to locate the active bleeder, if any. χ2 test was performed to show the differences of diagnostic sensitivity and accuracy between planar and SPECT/CT imaging. Results: In 56 patients with lower gastrointestinal bleeding, 50 patients showed abnormally concentrated radionuclide activity with planar images and 52 patients showed the similar imaging pattern with SPECT/CT. Among these patients, concordant bleeding with operation findings was found in 31 patients with planar images and 48 patients with SPECT/CT images. The sensitivity and accuracy were 89.3% (50/56) and 73.8% (31/42) in planar images, and 92.9% (52/56) and 92.3% (48/52) in SPECT/CT images (χ2=0.11, P>0.05; χ2=4.63, P<0.05). Conclusion: Hawkeye VG SPECT/CT imaging shows an effective, simple and accurate method and could be used for diagnosing and locating lower gastrointestinal bleeding. (authors)

  1. Positron Emission Tomography: Current Challenges and Opportunities for Technological Advances in Clinical and Preclinical Imaging Systems.

    Science.gov (United States)

    Vaquero, Juan José; Kinahan, Paul

    2015-01-01

    Positron emission tomography (PET) imaging is based on detecting two time-coincident high-energy photons from the emission of a positron-emitting radioisotope. The physics of the emission, and the detection of the coincident photons, give PET imaging unique capabilities for both very high sensitivity and accurate estimation of the in vivo concentration of the radiotracer. PET imaging has been widely adopted as an important clinical modality for oncological, cardiovascular, and neurological applications. PET imaging has also become an important tool in preclinical studies, particularly for investigating murine models of disease and other small-animal models. However, there are several challenges to using PET imaging systems. These include the fundamental trade-offs between resolution and noise, the quantitative accuracy of the measurements, and integration with X-ray computed tomography and magnetic resonance imaging. In this article, we review how researchers and industry are addressing these challenges.

  2. The clinical value of X-ray images of the teeth and jaws

    Science.gov (United States)

    Brocklebank, Laetitia

    2003-08-01

    X-ray images of the teeth and jaws are required for a variety of diagnostic purposes to supplement a clinical examination, and are invaluable for providing pictorial information about the structures that cannot be examined with direct vision. They can be acquired using traditional film systems which produce analogue images, or using a variety of alternative image receptors which result in a digital image. Irrespective of the method of image acquisition they are utilised by the dental surgeon in order to benefit their patients' management. Numerous disease processes can affect the teeth and jaws, in addition to a range of developmental abnormalities. These can be classified according to a radiological sieve, which also includes artefactual and iatrogenic features. The key components of the classification are: developmental, inflammatory, traumatic, cystic, neoplastic, osteodystrophies and systemic disorders. This paper will utilise examples of radiographic images of patients to illustrate components of this classification which are unique to the teeth and jaws.

  3. Diffusion Tensor Imaging and Tractography in Clinical Neurosciences

    Directory of Open Access Journals (Sweden)

    Mojtaba Zarei

    2003-05-01

    Full Text Available Rapidly evolving MR technology has allowed better understanding of structure and function of the human brain. Diffusion weighted MRI was developed two decades ago and it is now well established in diagnosis of acute ischaemia in patients with stroke. Diffusion tensor MRI uses the same principles but takes a step further allowing us to measure magnitude of the diffusion along different directions. This lead to the development of diffusion tensor tractography, a technique by which major neural pathways in the living brain can be visualized. There is a growing interest in exploring possible use of these techniques in clinical neurology and psychiatry. This article aims to review the principles of this technique and recent discoveries which may help us to better understand neurological and psychiatric disorders.

  4. Cerebral amyloid angiopathy-related inflammation: imaging findings and clinical outcome

    Energy Technology Data Exchange (ETDEWEB)

    Martucci, Matia [Vall d' Hebron University Hospital, Neuroradiology Unit, Radiology Department (IDI), Barcelona (Spain); Catholic University of Sacred Heart, ' ' A. Gemelli' ' University Hospital, Department of Radiological Sciences, Rome (Italy); Sarria, Silvana; Coscojuela, Pilar; Vert, Carla; Siurana, Sahyly; Auger, Cristina; Rovira, Alex [Vall d' Hebron University Hospital, Neuroradiology Unit, Radiology Department (IDI), Barcelona (Spain); Toledo, Manuel [Vall d' Hebron University Hospital, Epilepsy Unit, Neurology Department, Barcelona (Spain)

    2014-04-15

    We aim to investigate the clinical onset, computed tomography (CT) and magnetic resonance (MR) imaging findings, and follow-up of patients with cerebral amyloid angiopathy (CAA)-related inflammation, an uncommon but clinically striking presentation of CAA. We retrospectively reviewed the clinical manifestations, CT/MR imaging findings, and outcome of ten consecutive patients with CAA-related inflammation. In each patient, a brain CT study was performed at hospital admission, and brain MR imaging was carried out 2 to 4 days later. Clinical and radiologic follow-up findings were evaluated in all patients. The most common clinical onset was rapidly progressive cognitive decline, followed by focal neurological signs. Brain CT/MR showed unenhanced expansive subcortical lesions, corresponding to areas of vasogenic edema, associated with chronic lobar, cortical, or cortical-subcortical micro/macrohemorrhages. Clinical symptoms recovered in a few weeks under treatment in eight patients and spontaneously in the remaining two. MRI follow-up at 2 to 12 months after treatment showed resolution of the lesions. Three patients experienced symptomatic disease recurrence, with new lesions on CT/MR. In the absence of histological data, early recognition of the clinical symptoms and typical radiologic features of CAA-related inflammation is essential to enable timely establishment of proper treatment. (orig.)

  5. Septic pulmonary embolism caused by a Klebsiella pneumoniae liver abscess: clinical characteristics, imaging findings, and clinical courses

    Directory of Open Access Journals (Sweden)

    Deng-Wei Chou

    2015-06-01

    Full Text Available OBJECTIVES: Septic pulmonary embolism caused by a Klebsiella (K. pneumoniae liver abscess is rare but can cause considerable morbidity and mortality. However, clinical information regarding this condition is limited. This study was conducted to elucidate the full disease spectrum to improve its diagnosis and treatment. METHOD: We reviewed the clinical characteristics, imaging findings, and clinical courses of 14 patients diagnosed with septic pulmonary embolism caused by a K. pneumoniae liver abscess over a period of 9 years. RESULTS: The two most prevalent symptoms were fever and shortness of breath. Computed tomography findings included a feeding vessel sign (79%, nodules with or without cavities (79%, pleural effusions (71%, peripheral wedge-shaped opacities (64%, patchy ground-glass opacities (50%, air bronchograms within a nodule (36%, consolidations (21%, halo signs (14%, and lung abscesses (14%. Nine (64% of the patients developed severe complications and required intensive care. According to follow-up chest radiography, the infiltrates and consolidations were resolved within two weeks, and the nodular opacities were resolved within one month. Two (14% patients died of septic shock; one patient had metastatic meningitis, and the other had metastatic pericarditis. CONCLUSION: The clinical presentations ranged from insidious illness with fever and respiratory symptoms to respiratory failure and septic shock. A broad spectrum of imaging findings, ranging from nodules to multiple consolidations, was detected. Septic pulmonary embolism caused by a K. pneumoniae liver abscess combined with the metastatic infection of other vital organs confers a poor prognosis.

  6. SU-E-P-10: Imaging in the Cardiac Catheterization Lab - Technologies and Clinical Applications

    Energy Technology Data Exchange (ETDEWEB)

    Fetterly, K [Mayo Clinic, Rochester, MN (United States)

    2014-06-01

    Purpose: Diagnosis and treatment of cardiovascular disease in the cardiac catheterization laboratory is often aided by a multitude of imaging technologies. The purpose of this work is to highlight the contributions to patient care offered by the various imaging systems used during cardiovascular interventional procedures. Methods: Imaging technologies used in the cardiac catheterization lab were characterized by their fundamental technology and by the clinical applications for which they are used. Whether the modality is external to the patient, intravascular, or intracavity was specified. Specific clinical procedures for which multiple modalities are routinely used will be highlighted. Results: X-ray imaging modalities include fluoroscopy/angiography and angiography CT. Ultrasound imaging is performed with external, trans-esophageal echocardiography (TEE), and intravascular (IVUS) transducers. Intravascular infrared optical coherence tomography (IVOCT) is used to assess vessel endothelium. Relatively large (>0.5 mm) anatomical structures are imaged with x-ray and ultrasound. IVUS and IVOCT provide high resolution images of vessel walls. Cardiac CT and MRI images are used to plan complex cardiovascular interventions. Advanced applications are used to spatially and temporally merge images from different technologies. Diagnosis and treatment of coronary artery disease frequently utilizes angiography and intra-vascular imaging, and treatment of complex structural heart conditions routinely includes use of multiple imaging modalities. Conclusion: There are several imaging modalities which are routinely used in the cardiac catheterization laboratory to diagnose and treat both coronary artery and structural heart disease. Multiple modalities are frequently used to enhance the quality and safety of procedures. The cardiac catheterization laboratory includes many opportunities for medical physicists to contribute substantially toward advancing patient care.

  7. A portable device for small animal SPECT imaging in clinical gamma-cameras

    International Nuclear Information System (INIS)

    Molecular imaging is reshaping clinical practice in the last decades, providing practitioners with non-invasive ways to obtain functional in-vivo information on a diversity of relevant biological processes. The use of molecular imaging techniques in preclinical research is equally beneficial, but spreads more slowly due to the difficulties to justify a costly investment dedicated only to animal scanning. An alternative for lowering the costs is to repurpose parts of old clinical scanners to build new preclinical ones. Following this trend, we have designed, built, and characterized the performance of a portable system that can be attached to a clinical gamma-camera to make a preclinical single photon emission computed tomography scanner. Our system offers an image quality comparable to commercial systems at a fraction of their cost, and can be used with any existing gamma-camera with just an adaptation of the reconstruction software

  8. Medical imaging in clinical applications algorithmic and computer-based approaches

    CERN Document Server

    Bhateja, Vikrant; Hassanien, Aboul

    2016-01-01

    This volume comprises of 21 selected chapters, including two overview chapters devoted to abdominal imaging in clinical applications supported computer aided diagnosis approaches as well as different techniques for solving the pectoral muscle extraction problem in the preprocessing part of the CAD systems for detecting breast cancer in its early stage using digital mammograms. The aim of this book is to stimulate further research in medical imaging applications based algorithmic and computer based approaches and utilize them in real-world clinical applications. The book is divided into four parts, Part-I: Clinical Applications of Medical Imaging, Part-II: Classification and clustering, Part-III: Computer Aided Diagnosis (CAD) Tools and Case Studies and Part-IV: Bio-inspiring based Computer Aided diagnosis techniques. .

  9. Updating magnetic resonance imaging of small bowel: Imaging protocols and clinical indications

    Institute of Scientific and Technical Information of China (English)

    Jiong Zhu; Jian-Rong Xu; Hong-Xia Gong; Yan Zhou

    2008-01-01

    High soft tissue contrast resolution,acquisition of multi-planar images and the possibility to obtain functional information make magnetic resonance an interesting imaging technique to evaluate the small bowel disease.The absence of ionizing radiation is an important feature of magnetic resonance imaging (MRI) examinations because inflammatory diseases such as Crohn's disease (CD) are studied most frequently,which are prevalent among children and young adults.MRI,using modern equipment and a rigorous technical approach,can offer detailed morphologic information and functional data on the small bowel.This article discusses the MRI protocols for small bowel and the MR imaging findings of small bowel diseases,such as CD and small bowel neoplasms.

  10. Whole-body MR imaging. Practical issues, clinical applications, and future directions.

    Science.gov (United States)

    Eustace, S J; Walker, R; Blake, M; Yucel, E K

    1999-05-01

    Whole-body MR imaging is in evolution, and although accepting and recognizing limitations, it is likely that both technique and incurred acquisition times will shorten over the next decade. Although the development of dedicated whole-body MR scanners appears to offer the greatest promise for the future, the development of moving table tops, optimized pulse sequences, and advances in gradient technology now facilitate practical whole-body MR imaging using existing clinical systems.

  11. Whole-body magnetic resonance imaging: techniques, clinical indications, and future applications.

    Science.gov (United States)

    Walker, R E; Eustace, S J

    2001-01-01

    This article reviews developments in both pulse sequence design and gradient technology that facilitate rapid imaging of the whole body. It discusses its application in patients with bone marrow neoplasms, including metastases, lymphoma, and myeloma and emphasizes the value of whole-body magnetic resonance imaging in patients with known vertebral lesions to detect other bone lesions that are easier to biopsy. It outlines possible applications in well-defined clinical situations, including pregnancy and unknown primary tumor.

  12. Is Your System Calibrated? MRI Gradient System Calibration for Pre-Clinical, High-Resolution Imaging

    OpenAIRE

    James O'Callaghan; Jack Wells; Simon Richardson; Holly Holmes; Yichao Yu; Simon Walker-Samuel; Bernard Siow; Lythgoe, Mark F

    2014-01-01

    High-field, pre-clinical MRI systems are widely used to characterise tissue structure and volume in small animals, using high resolution imaging. Both applications rely heavily on the consistent, accurate calibration of imaging gradients, yet such calibrations are typically only performed during maintenance sessions by equipment manufacturers, and potentially with acceptance limits that are inadequate for phenotyping. To overcome this difficulty, we present a protocol for gradient calibration...

  13. White Matter Fiber Tracking Computation Based on Diffusion Tensor Imaging for Clinical Applications

    OpenAIRE

    Dellani, Paulo R.; Glaser, Martin; Wille, Paulo R.; Vucurevic, Goran; Stadie, Axel; Bauermann, Thomas; Tropine, Andrei; Perneczky, Axel; von Wangenheim, Aldo; Stoeter, Peter

    2006-01-01

    Fiber tracking allows the in vivo reconstruction of human brain white matter fiber trajectories based on magnetic resonance diffusion tensor imaging (MR-DTI), but its application in the clinical routine is still in its infancy. In this study, we present a new software for fiber tracking, developed on top of a general-purpose DICOM (digital imaging and communications in medicine) framework, which can be easily integrated into existing picture archiving and communication system (PACS) of radiol...

  14. Companion diagnostics and molecular imaging-enhanced approaches for oncology clinical trials.

    Science.gov (United States)

    Van Heertum, Ronald L; Scarimbolo, Robert; Ford, Robert; Berdougo, Eli; O'Neal, Michael

    2015-01-01

    In the era of personalized medicine, diagnostic approaches are helping pharmaceutical and biotechnology sponsors streamline the clinical trial process. Molecular assays and diagnostic imaging are routinely being used to stratify patients for treatment, monitor disease, and provide reliable early clinical phase assessments. The importance of diagnostic approaches in drug development is highlighted by the rapidly expanding global cancer diagnostics market and the emergent attention of regulatory agencies worldwide, who are beginning to offer more structured platforms and guidance for this area. In this paper, we highlight the key benefits of using companion diagnostics and diagnostic imaging with a focus on oncology clinical trials. Nuclear imaging using widely available radiopharmaceuticals in conjunction with molecular imaging of oncology targets has opened the door to more accurate disease assessment and the modernization of standard criteria for the evaluation, staging, and treatment responses of cancer patients. Furthermore, the introduction and validation of quantitative molecular imaging continues to drive and optimize the field of oncology diagnostics. Given their pivotal role in disease assessment and treatment, the validation and commercialization of diagnostic tools will continue to advance oncology clinical trials, support new oncology drugs, and promote better patient outcomes.

  15. Comparison of 3 T and 7 T MRI clinical sequences for ankle imaging

    International Nuclear Information System (INIS)

    The purpose of this study was to compare 3 T and 7 T signal-to-noise and contrast-to noise ratios of clinical sequences for imaging of the ankles with optimized sequences and dedicated coils. Ten healthy volunteers were examined consecutively on both systems with three clinical sequences: (1) 3D gradient-echo, T1-weighted; (2) 2D fast spin-echo, PD-weighted; and (3) 2D spin-echo, T1-weighted. SNR was calculated for six regions: cartilage; bone; muscle; synovial fluid; Achilles tendon; and Kager's fat-pad. CNR was obtained for cartilage/bone, cartilage/fluid, cartilage/muscle, and muscle/fat-pad, and compared by a one-way ANOVA test for repeated measures. Mean SNR significantly increased at 7 T compared to 3 T for 3D GRE, and 2D TSE was 60.9% and 86.7%, respectively. In contrast, an average SNR decrease of almost 25% was observed in the 2D SE sequence. A CNR increase was observed in 2D TSE images, and in most 3D GRE images. There was a substantial benefit from ultra high-field MR imaging of ankles with routine clinical sequences at 7 T compared to 3 T. Higher SNR and CNR at ultra-high field MR scanners may be useful in clinical practice for ankle imaging. However, carefully optimized protocols and dedicated extremity coils are necessary to obtain optimal results.

  16. Utilizing data grid architecture for the backup and recovery of clinical image data.

    Science.gov (United States)

    Liu, Brent J; Zhou, M Z; Documet, J

    2005-01-01

    Grid Computing represents the latest and most exciting technology to evolve from the familiar realm of parallel, peer-to-peer and client-server models. However, there has been limited investigation into the impact of this emerging technology in medical imaging and informatics. In particular, PACS technology, an established clinical image repository system, while having matured significantly during the past ten years, still remains weak in the area of clinical image data backup. Current solutions are expensive or time consuming and the technology is far from foolproof. Many large-scale PACS archive systems still encounter downtime for hours or days, which has the critical effect of crippling daily clinical operations. In this paper, a review of current backup solutions will be presented along with a brief introduction to grid technology. Finally, research and development utilizing the grid architecture for the recovery of clinical image data, in particular, PACS image data, will be presented. The focus of this paper is centered on applying a grid computing architecture to a DICOM environment since DICOM has become the standard for clinical image data and PACS utilizes this standard. A federation of PACS can be created allowing a failed PACS archive to recover its image data from others in the federation in a seamless fashion. The design reflects the five-layer architecture of grid computing: Fabric, Resource, Connectivity, Collective, and Application Layers. The testbed Data Grid is composed of one research laboratory and two clinical sites. The Globus 3.0 Toolkit (Co-developed by the Argonne National Laboratory and Information Sciences Institute, USC) for developing the core and user level middleware is utilized to achieve grid connectivity. The successful implementation and evaluation of utilizing data grid architecture for clinical PACS data backup and recovery will provide an understanding of the methodology for using Data Grid in clinical image data backup for

  17. Inter-observer variation in masked and unmasked images for quality evaluation of clinical radiographs

    International Nuclear Information System (INIS)

    Purpose: To investigate the influence of masking on the inter-observer variation in image quality evaluation of clinical radiographs of chest and lumbar spine. Background: Inter-observer variation is a big problem in image quality evaluation since this variation is often much bigger than the variation in image quality between, for example, two radiographic systems. In this study, we have evaluated the effect of masking on the inter-observer variation. The idea of the masking was to force every observer to view exactly the same part of the image and to avoid the effect of the overall 'first impression' of the image. A discussion with a group of European expert radiologists before the study indicated that masking might be a good way to reduce the inter-observer variation. Methods: Five chest and five lumbar spine radiographs were collected together with detailed information regarding exposure conditions. The radiographs were digitised with a high-performance scanner and five different manipulations were performed, simulating five different exposure conditions. The contrast, noise and spatial resolution were manipulated by this method. The images were printed onto the film and the individual masks were produced for each film, showing only the parts of the images that were necessary for the image quality evaluation. The quality of the images was evaluated on ordinary viewing boxes by a large group of experienced radiologists. The images were examined with and without the masks with a set of image criteria (if fulfilled, 1 point; and not fulfilled, 0 point), and the mean score was calculated for each simulated exposure condition. Results: The results of this study indicate that - contrary to what was supposed - the inter-observer variation increased when the images were masked. In some cases, especially for chest, this increase was statistically significant. Conclusions: Based on the results of this study, image masking in studies of fulfilment of image criteria cannot

  18. The Clinical Characteristics and Imaging Findings of Morning Glory Syndrome

    Institute of Scientific and Technical Information of China (English)

    Jun HU

    2008-01-01

    To investigate the features of CT, ultrasonography and fundus fluorescein angiography(FFA) of morning glory syndrome, the data on CT, A/B-scan ultrasonography and fundus fluorescein angiography (FFA) were retrospectively analyzed in 8 cases of morning glory syndrome (MGS).Among those cases, 6 were examined with CT, 4 with FFA and 8 with A/B-scan ultrasonography.Results showed that the characteristics of CT, A/B-scan ultrasonography and FFA in MGS included:(1) The attachment spot of optic nerve became thin and vitreous body protruded to the posterior wall of eyeball with a spherical shape on CT image; (2) in the early period of FFA, hypofluorescence appeared on the optic, the abnormal arteriae and veins around the optic papilla were displayed clearly and in the late period, optic disc was stained with fluorescein; (3) on B-scan ultrasonogram, the vitreous cavity extended to the posterior pole and optic papilla, and projected to the basal part of muscle cones and thus the posterior part of vitreous cavity looked like an upside-down bottleneck. Sometimes the echogenic band of retinal detachment could also be seen. On A-scan ultrasonogram, both vitreous cavity and bottleneck showed no ultrasonic echoes and presented a base line without any evident wave crest. It is concluded that CT, A/B-scan ultrasonography and FFA could show the imageological features of MGS from different aspects, which helps clinicians to differentiate it from other diseases such as optic disc coloboma. CT and A/B-scan ultrasonography, in particular, are considered to be reliable imageological methods for the accurate diagnosis of MGS and are superior to the traditional techniques.

  19. Feasibility and Merits of Performing Preclinical Imaging on Clinical Radiology and Nuclear Medicine Systems

    Directory of Open Access Journals (Sweden)

    Mehmet Bilgen

    2013-01-01

    Full Text Available Aim. Researchers have limited access to systems dedicated to imaging small laboratory animals. This paper aims to investigate the feasibility and merits of performing preclinical imaging on clinical systems. Materials and Methods. Scans were performed on rat and mouse models of diseases or injuries on four radiology systems, tomosynthesis, computed tomography (CT, positron emission tomography/computed tomography (PET-CT, and Magnetic Resonance Imaging (MRI, based on the availability at the author’s institute. Results. Tomosysthesis delineated soft tissue anatomy and hard tissue structure with superb contrast and spatial resolution at minimal scan time and effort. CT allowed high resolution volumetric visualization of bones. Molecular imaging with PET was useful for detecting cancerous tissue in mouse but at the expense of poor resolution. MRI depicted abnormal or intervened tissue at quality and resolution sufficient for experimental studies. The paper discussed limitations of the clinical systems in preclinical imaging as well as challenges regarding the need of additional gadgets, modifications, or upgrades required for longitudinally scanning animals under anesthesia while monitoring their vital signs. Conclusion. Clinical imaging technologies can potentially make cost-effective and efficient contributions to preclinical efforts in obtaining anatomical, structural, and functional information from the underlying tissue while minimally compromising the data quality in certain situations.

  20. Federated Web-accessible Clinical Data Management within an Extensible NeuroImaging Database

    OpenAIRE

    Ozyurt, I. Burak; Keator, David B.; Wei, Dingying; Fennema-Notestine, Christine; Pease, Karen R.; Bockholt, Jeremy; Grethe, Jeffrey S.

    2010-01-01

    Managing vast datasets collected throughout multiple clinical imaging communities has become critical with the ever increasing and diverse nature of datasets. Development of data management infrastructure is further complicated by technical and experimental advances that drive modifications to existing protocols and acquisition of new types of research data to be incorporated into existing data management systems. In this paper, an extensible data management system for clinical neuroimaging s...

  1. Degeneration of Leiomyoma in Patients Referred for Uterine Fibroid Embolization: Incidence, Imaging Features and Clinical Characteristics

    OpenAIRE

    Han, Seung Chul; Kim, Man-Deuk; Jung, Dae Chul; Lee, Myungsu; Lee, Mu Sook; Park, Sung Il; Won, Jong Yun; Lee, Do Yun; Lee, Kwang Hun

    2012-01-01

    Purpose Imaging features and clinical characteristics of degenerated leiomyoma in patients referred for uterine fibroid embolization (UFE) were analyzed to assess the incidence of degenerated leiomyoma. Materials and Methods Patients referred for UFE between 2008 and 2009 were retrospectively analyzed (n=276). Patients ranged in age from 27 to 51 years (mean 38.0 years). All patients underwent screening MRI with contrast enhancement. Medical histories and clinical symptoms were evaluated. Res...

  2. Strain Imaging: The Emergence of Speckle Tracking Echocardiography into Clinical Pediatric Cardiology.

    Science.gov (United States)

    Colquitt, John L; Pignatelli, Ricardo H

    2016-01-01

    Speckle tracking echocardiography measures myocardial strain and allows for the quantification of regional and global left and right ventricular function. A growing body of literature is supporting its transition from research into clinical practice. This article aims to provide a practical review of strain imaging as it applies to congenital and pediatric heart disease, with the goals of increasing literacy and advocating for greater clinical integration. PMID:26879728

  3. Term and Preterm Children with Cerebral Palsy: Etiology, Clinic and Magnetic Resonance Imaging Findings

    OpenAIRE

    Adın, Sait; Aslan, Mehmet; DOĞAN, Metin; Yakıncı, Cengiz; Alkan, Alpay

    2009-01-01

    Aim: Cerebral palsy (CP) is a frequent neurologic disease of term and preterm neonates. The disorder has various causes and the etiology, clinical manifestations and radiological screening findings are different in term and preterms. Thirty six preterm and 66 term CP patients aged between 6 months-16 years were evaluated in this study and were compared according to their etiology, clinical manifestation and cerebral Magnetic Resonance Imagıng (MRI) findings statistically. Material and Met...

  4. Canavan disease - unusual imaging features in a child with mild clinical presentation

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Ho V.; Ishak, Gisele E. [University of Washington, Department of Radiology, Seattle Children' s Hospital, Seattle, WA (United States)

    2015-03-01

    Canavan disease is a rare hereditary leukodystrophy that manifests in early childhood. Associated with rapidly progressive clinical deterioration, it usually results in death by the third year of life. The predominant MRI appearance is diffuse and symmetrical white matter disease. We discuss an atypical, late presentation of Canavan disease with a benign clinical course and uncharacteristic imaging features. This case introduces a previously unreported pattern of diffuse cortical abnormality without significant white matter involvement. (orig.)

  5. Clinical review: Clinical imaging of the sublingual microcirculation in the critically ill - where do we stand?

    NARCIS (Netherlands)

    R. Bezemer (Rick); S.A. Bartels (Sebastiaan); J. Bakker (Jan); C. Ince (Can)

    2012-01-01

    textabstractA growing body of evidence exists associating depressed microcirculatory function and morbidity and mortality in a wide array of clinical scenarios. It has been suggested that volume replacement therapy using fluids and/or blood in combination with vasoactive agents to modulate macro- an

  6. The issues and tentative solutions for contrast-enhanced magnetic resonance imaging at ultra-high field strength.

    Science.gov (United States)

    Fries, Peter; Morelli, John N; Lux, Francois; Tillement, Olivier; Schneider, Günther; Buecker, Arno

    2014-01-01

    Magnetic resonance imaging (MRI) performed at ultra-high field strengths beyond 3 Tesla (T) has become increasingly prevalent in research and preclinical applications. As such, the inevitable clinical implementation of such systems lies on the horizon. The major benefit of ultra-high field MRI is the markedly increased signal-to-noise ratios achievable, enabling acquisition of MR images with simultaneously greater spatial and temporal resolution. However, at field strengths higher than 3 T, the efficacy of Gd(III)-based contrast agents is diminished due to decreased r1 relaxivity, somewhat limiting imaging of the vasculature and contrast-enhanced imaging of tumors. There have been extensive efforts to design new contrast agents with high r1 relaxivities based on macromolecular compounds or nanoparticles; however, the efficacy of these agents at ultra-high field strengths has not yet been proven. The aim of this review article is to provide an overview of the basic principles of MR contrast enhancement processes and to highlight the main factors influencing relaxivity. In addition, challenges and opportunities for contrast-enhanced MRI at ultra-high field strengths will be explored. Various approaches for the development of effective contrast agent molecules that are suitable for a broad spectrum of applied field strengths will be discussed in the context of the current literature.

  7. 3T imaging of cervical carotid plaque using a 3D T1-weighted sequence. Experience of 130 consecutive cases

    International Nuclear Information System (INIS)

    Three-dimensional (3D) T1-weighted imaging is reported to depict hemorrhagic plaque of the carotid artery with high signal intensity. Using a 3-tesla MR imaging unit, we prospectively evaluated how often 3D T1-weighted imaging can detect such plaque in 130 consecutive patients with (Group A, 80 patients) and without (Group B, 50 patients) ischemic brain disease. We evaluated the presence or absence of carotid plaque (s) in each patient, compared the signal intensity of plaque to that of the sternocleidomastoid muscle, and calculated the signal ratio of plaque to muscle (plaque/muscle). High intensity was defined as a signal ratio of 2 or greater. The degree of intravascular nullity was visually rated as good or poor and evaluated quantitatively. We investigated factors including diabetes, hypertension, and hyperlipidemia to determine whether those factors affect the presence of high-signal plaques. The degree of intravascular nullity was poor in 30.8% of all patients. High-signal plaque was observed more frequently in Group A than Group B (p=0.003). No risk factor was significantly associated with the presence of high-signal plaques. The use of 3D T1-weighted plaque imaging with a 3T unit contributes to the screening of unstable plaque that might otherwise be missed in a clinical setting. (author)

  8. Clinical study and image diagnosis of nasal bone fracture

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Takenori; Suzuki, Naohiro; Okitsu, Takuji [Sendai City Hospital (Japan)

    2002-01-01

    In this study we reviewed the clinical features, diagnoses and treatments of 232 cases of nasal bone fracture cases treated at our department from January 1994 to June 2000. A marked predominance of males in the age range of 10-29 years was noted. Analysis of the causes of the nasal fractures were attributed to fighting (66 cases), traffic accidents (64 cases), sports (56 cases) and others (46 cases). The external appearance of nasal fractures were divided into 5 types, 85 cases of the displacement type, 27 cases of the depressed type, 32 of the mixed type, 56 of the non-deformation type and 32 of the unclassified type because of facial swelling. The sensitivity of conventional X-ray examination in identifying nasal fractures was 75.6%. Computed tomography scan (CT scan) was performed in 196 patients and showed that the middle and lower portions of nasal bones were fractured more easily than those of the upper portion. Nasal septum fracture occurred in 22 cases (11.2%). Other facial fractures combined with nasal fracture were found in 40 cases (20.4%). The type of combined fracture depended on the cause of the injury, for example, the combination of nasal and blow-out fracture was often caused by fighting, and many combined fractures of more than two facial bones resulted from traffic accidents. A total of 83 patients (35.8%) received reduction of the nasal bone fractures under general anaesthesia. The measurement of irradiation of each radiological examination revealed that the exposed dose of the newest model CT was similar to that of the conventional X-ray examination and tomography. (author)

  9. Relationship between clinical findings of temporomandibular disorders and magnetic resonance imaging

    International Nuclear Information System (INIS)

    The present study was conducted to investigate the relationship between magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ) and clinical findings of patients having symptoms of temporomandibular disorders, and to consider the possibility to grasp the internal derangement of the TMJ from clinical findings. Subjects were 80 patients who visited to ask orthodontic treatment 16 males and 64 females. The average age was 22 years and 4 months. We performed a investigation of both their previous and present illness. In addition, to decide the correct condition concerning the internal derangement of the TMJ, patients were given MRI examinations (G. E. medical system Signa 1.5 Tesla) before orthodontic treatment. Results were as follows: The three symptoms of temporomandibular disorders-noise, pain, and abnormal mandibular movement, were not related to constant disk displacement. It seemed difficult to infer and obtain the diagnosis of the condition of internal derangement of the TMJ only from clinical findings. In a dental clinics having no medical imaging instrument such as MRI, it was, however, considered that the following items will make it possible to define the condition of internal derangements of the TMJ from clinical findings. As to respects concerning clinical findings, it is necessary to consider the previous illness as well as present illness. TMJ noise indicates a higher relationship to the disk displacement in MRI findings. The temporomandibular joint with plural symptoms indicated a higher incidence of disk displacement examined by MR Imaging than that with a single symptom. (author)

  10. Towards the routine use of brain imaging to aid the clinical diagnosis of disorders of consciousness.

    Science.gov (United States)

    Coleman, M R; Davis, M H; Rodd, J M; Robson, T; Ali, A; Owen, A M; Pickard, J D

    2009-09-01

    Clinical audits have highlighted the many challenges and dilemmas faced by clinicians assessing persons with disorders of consciousness (vegetative state and minimally conscious state). The diagnostic decision-making process is highly subjective, dependent upon the skills of the examiner and invariably dictated by the patients' ability to move or speak. Whilst a considerable amount has been learnt since Jennett and Plum coined the term 'vegetative state', the assessment process remains largely unchanged; conducted at the bedside, using behavioural assessment tools, which are susceptible to environmental and physiological factors. This has created a situation where the rate of misdiagnosis is unacceptably high (up to 43%). In order to address these problems, various functional brain imaging paradigms, which do not rely upon the patient's ability to move or speak, have been proposed as a source of additional information to inform the diagnostic decision making process. Although accumulated evidence from brain imaging, particularly functional magnetic resonance imaging (fMRI), has been encouraging, the empirical evidence is still based on relatively small numbers of patients. It remains unclear whether brain imaging is capable of informing the diagnosis beyond the behavioural assessment and whether brain imaging has any prognostic utility. In this study, we describe the functional brain imaging findings from a group of 41 patients with disorders of consciousness, who undertook a hierarchical speech processing task. We found, contrary to the clinical impression of a specialist team using behavioural assessment tools, that two patients referred to the study with a diagnosis of vegetative state did in fact demonstrate neural correlates of speech comprehension when assessed using functional brain imaging. These fMRI findings were found to have no association with the patient's behavioural presentation at the time of investigation and thus provided additional diagnostic

  11. Childhood extracranial neoplasms: the role of imaging in drug development and clinical trials

    Energy Technology Data Exchange (ETDEWEB)

    Fowkes, Lucy A.; Koh, Dow-Mu; MacVicar, David [Royal Marsden NHS Foundation Trust, Department of Radiology, Sutton, Surrey (United Kingdom); Collins, David J.; Jerome, Neil P. [Institute of Cancer Research, Cancer Research UK and EPSRC Cancer Imaging Centre, Sutton, Surrey (United Kingdom); Chua, Sue C. [Royal Marsden NHS Foundation Trust, Nuclear Medicine and PET Department, Sutton, Surrey (United Kingdom); Pearson, Andrew D.J. [Royal Marsden NHS Foundation Trust, Paediatric Drug Development Unit, Children and Young People' s Unit, Sutton, Surrey (United Kingdom)

    2015-10-15

    Cancer is the leading cause of death in children older than 1 year of age and new drugs are necessary to improve outcomes. Imaging is crucial to the drug development process and assessment of therapeutic response. In adults, tumours are often assessed with CT using size criteria. Unfortunately, techniques established in adults are not necessarily applicable in children due to differing pathophysiology, ability to cooperate and increased susceptibility to ionising radiation. MRI, in particular quantitative MRI, has to date not been fully utilised in children with extracranial neoplasms. The specific challenges of imaging in children, the potential for functional imaging techniques to inform upon and their inclusion in clinical trials are discussed. (orig.)

  12. Management of Low-Flow Vascular Malformations: Clinical Presentation, Classification, Patient Selection, Imaging and Treatment

    Energy Technology Data Exchange (ETDEWEB)

    McCafferty, Ian, E-mail: ian.mccafferty@uhb.nhs.uk [Queen Elizabeth Hospital Birmingham (QEHB) & Birmingham Children’s Hospital (BCH) (United Kingdom)

    2015-10-15

    This review article aims to give an overview of the current state of imaging, patient selection, agents and techniques used in the management of low-flow vascular malformations. The review includes the current classifications for low-flow vascular malformations including the 2014 updates. Clinical presentation and assessment is covered with a detailed section on the common sclerosant agents used to treat low-flow vascular malformations, including dosing and common complications. Imaging is described with a guide to a simple stratification of the use of imaging for diagnosis and interventional techniques.

  13. Clinics in diagnostic imaging (76). Left extradural-intradural lumbar neurofibroma.

    Science.gov (United States)

    Tsui, E Y K; Peh, W C G; Htoo, M M

    2002-08-01

    A 62-year-old woman presented with weight loss, anoexia and back pain. She was found to have a palpable left abdominal mass. Radiographs, CT and MR imaging revealed a large left 3rd lumbar neurogenic tumour with both intra- and extradural components. A neurofibroma was excised and the diagnosis was confirmed histopathologically. The patient has no recurrence at six years follow-up. The pathological classifications, clinical and imaging features of neurogenic tumours are discussed. With the knowledge of characteristic imaging features, these tumours can be differentiated from other types of intradural-extramedullary tumours. PMID:12507033

  14. Management of Low-Flow Vascular Malformations: Clinical Presentation, Classification, Patient Selection, Imaging and Treatment

    International Nuclear Information System (INIS)

    This review article aims to give an overview of the current state of imaging, patient selection, agents and techniques used in the management of low-flow vascular malformations. The review includes the current classifications for low-flow vascular malformations including the 2014 updates. Clinical presentation and assessment is covered with a detailed section on the common sclerosant agents used to treat low-flow vascular malformations, including dosing and common complications. Imaging is described with a guide to a simple stratification of the use of imaging for diagnosis and interventional techniques

  15. Clinical Experience With A High Resolution Digital Imaging System For Gastro-Intestinal Radiology

    Science.gov (United States)

    Edmonds, E. W.; Rowlands, J. A.; Hynes, D. M.; Toth, B. D.; Porter, A. J.

    1987-01-01

    In our department, it is planned that the gastro-intestinal fluoroscopic area will be equipped entirely with digital imaging systems. The use of the 1024 X 1024 pixel frame store, backed by a hard disc for rapid image transfer, and the production of hard copy on a laser imager has reached the point where clinical efficacy and acceptance are assured. The further addition of facilities for annotation and the application of digital post-processing techniques are being explored both at the clinical site and at the research laboratorieS. The use of laser imaging has produced a further improvement in image quality and some of the practical problems related to this apparatus will be described. The availability of larger capacity laser disc image storage enables the local area network or "mini-PACS" system for fluoroscopy areas to become a concept worthy of investigation. We present our experience over a number of years with these systems, together with our latest investigations into potential applications of laser technology to the practice of radiology in a busy imaging centre.

  16. Progress in clinical research and application of resting state functional brain imaging

    International Nuclear Information System (INIS)

    Resting state functional brain imaging experimental design is free of stimulus task and offers various parametric maps through different data-driven post processing methods with endogenous BOLD signal changes as the source of imaging. Mechanism of resting state brain activities could be extensively studied with improved patient compliance and clinical application compared with task related functional brain imaging. Also resting state functional brain imaging can be used as a method of data acquisition, with implicit neuronal activity as a kind of experimental design, to reveal characteristic brain activities of epileptic patient. Even resting state functional brain imaging data processing method can be used to analyze task related functional MRI data, opening new horizons of task related functional MRI study. (authors)

  17. Clinical Intravoxel Incoherent Motion and Diffusion MR Imaging: Past, Present, and Future.

    Science.gov (United States)

    Iima, Mami; Le Bihan, Denis

    2016-01-01

    The concept of diffusion magnetic resonance (MR) imaging emerged in the mid-1980s, together with the first images of water diffusion in the human brain, as a way to probe tissue structure at a microscopic scale, although the images were acquired at a millimetric scale. Since then, diffusion MR imaging has become a pillar of modern clinical imaging. Diffusion MR imaging has mainly been used to investigate neurologic disorders. A dramatic application of diffusion MR imaging has been acute brain ischemia, providing patients with the opportunity to receive suitable treatment at a stage when brain tissue might still be salvageable, thus avoiding terrible handicaps. On the other hand, it was found that water diffusion is anisotropic in white matter, because axon membranes limit molecular movement perpendicularly to the nerve fibers. This feature can be exploited to produce stunning maps of the orientation in space of the white matter tracts and brain connections in just a few minutes. Diffusion MR imaging is now also rapidly expanding in oncology, for the detection of malignant lesions and metastases, as well as monitoring. Water diffusion is usually largely decreased in malignant tissues, and body diffusion MR imaging, which does not require any tracer injection, is rapidly becoming a modality of choice to detect, characterize, or even stage malignant lesions, especially for breast or prostate cancer. After a brief summary of the key methodological concepts beyond diffusion MR imaging, this article will give a review of the clinical literature, mainly focusing on current outstanding issues, followed by some innovative proposals for future improvements. PMID:26690990

  18. Interventional multispectral photoacoustic imaging with a clinical linear array ultrasound probe for guiding nerve blocks

    Science.gov (United States)

    Xia, Wenfeng; West, Simeon J.; Nikitichev, Daniil I.; Ourselin, Sebastien; Beard, Paul C.; Desjardins, Adrien E.

    2016-03-01

    Accurate identification of tissue structures such as nerves and blood vessels is critically important for interventional procedures such as nerve blocks. Ultrasound imaging is widely used as a guidance modality to visualize anatomical structures in real-time. However, identification of nerves and small blood vessels can be very challenging, and accidental intra-neural or intra-vascular injections can result in significant complications. Multi-spectral photoacoustic imaging can provide high sensitivity and specificity for discriminating hemoglobin- and lipid-rich tissues. However, conventional surface-illumination-based photoacoustic systems suffer from limited sensitivity at large depths. In this study, for the first time, an interventional multispectral photoacoustic imaging (IMPA) system was used to image nerves in a swine model in vivo. Pulsed excitation light with wavelengths in the ranges of 750 - 900 nm and 1150 - 1300 nm was delivered inside the body through an optical fiber positioned within the cannula of an injection needle. Ultrasound waves were received at the tissue surface using a clinical linear array imaging probe. Co-registered B-mode ultrasound images were acquired using the same imaging probe. Nerve identification was performed using a combination of B-mode ultrasound imaging and electrical stimulation. Using a linear model, spectral-unmixing of the photoacoustic data was performed to provide image contrast for oxygenated and de-oxygenated hemoglobin, water and lipids. Good correspondence between a known nerve location and a lipid-rich region in the photoacoustic images was observed. The results indicate that IMPA is a promising modality for guiding nerve blocks and other interventional procedures. Challenges involved with clinical translation are discussed.

  19. Patterns of Hepatosplenic Brucella Abscesses on Cross-Sectional Imaging: A Review of Clinical and Imaging Features.

    Science.gov (United States)

    Heller, Tom; Bélard, Sabine; Wallrauch, Claudia; Carretto, Edoardo; Lissandrin, Raffaella; Filice, Carlo; Brunetti, Enrico

    2015-10-01

    While diffuse involvement of liver and spleen is frequently seen in brucellosis, suppurative abscesses caused by Brucella are less common but well described. With the increased availability of cross-sectional imaging techniques, reports have become more frequent. Four patients with hepatosplenic abscesses caused by Brucella spp. are described and included in a review of 115 previously published cases. Clinical characteristics and patterns on ultrasound (US) and computed tomography imaging were analyzed. Furthermore, the proportion of patients with brucellosis affected by suppurative hepatosplenic lesions was estimated. Hepatosplenic abscesses were seen in 1.2% of patients with brucellosis and were mostly caused by Brucella melitensis. Imaging analysis revealed two main distinct patterns. Solitary abscesses involving liver more frequently than spleen, and showing characteristic central calcifications, characterize the first pattern. Multiple smaller abscesses, frequent spleen involvement, and absence of calcifications characterize the second pattern. Blood and aspirate cultures were frequently negative, however, the positivity rate increased over the past years. Indirect Coombs test was positive in 96%. Half of the patients were cured by antibiotic treatment; case fatality in this series was 1.9%. Hepatosplenic abscesses due to Brucella infections have characteristic imaging findings. Clinicians should be aware of these and the proactive use of cross-sectional imaging, particularly US, should be encouraged in endemic regions.

  20. Image processing for the rest of us: the potential utility of inexpensive computerized image analysis in clinical pathology and radiology.

    Science.gov (United States)

    McEachron, D L; Hess, S; Knecht, L B; True, L D

    1989-01-01

    Recent progress in computer technology in both hardware and software, combined with marked cost reductions, have placed quantitatively accurate video densitometry systems within the reach of the individual clinician, biomedical researcher, and community hospital. While much of the attention generated by advances in image processing has focussed on larger scale procedures, such as CAT, chemical shift, and positron emission tomography, important applications can be found for considerably more modest systems. In this article, we discuss three such applications of DUMAS, a personal computer-based imaging system developed by the Image Processing Center at Drexel University. A potential technique for quantifying numbers of estrogen receptors in tumorous breast tissue samples as a predictor of patient responsiveness to hormonal therapy is described first, along with possible sources of error. The second application, also related to clinical pathology and cancer, outlines methods for relating changes in nuclear and cell morphology to the diagnosis of Sezary Cell Syndrome. The utility of binary image filtering methods in the classification of cell types is discussed. The third application involves the development of a semi-automatic procedure for the determination of vessel diameter in arteriograms. A detailed description of the optimization and curve-fitting algorithms is provided along with preliminary test results comparing various approaches. The need for user demand to fuel research and development in small-scale imaging systems is also discussed. PMID:2647281

  1. The Value of Neurosurgical and Intraoperative Magnetic Resonance Imaging and Diffusion Tensor Imaging Tractography in Clinically Integrated Neuroanatomy Modules: A Cross-Sectional Study

    Science.gov (United States)

    Familiari, Giuseppe; Relucenti, Michela; Heyn, Rosemarie; Baldini, Rossella; D'Andrea, Giancarlo; Familiari, Pietro; Bozzao, Alessandro; Raco, Antonino

    2013-01-01

    Neuroanatomy is considered to be one of the most difficult anatomical subjects for students. To provide motivation and improve learning outcomes in this area, clinical cases and neurosurgical images from diffusion tensor imaging (DTI) tractographies produced using an intraoperative magnetic resonance imaging apparatus (MRI/DTI) were presented and…

  2. Clinically significant skeletal variations of the shoulder and the wrist: role of MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mellado, J.M.; Sauri, A. [Institut de Diagnostic per la Imatge, Hospital Universitari de Tarragona Joan XXIII, Carrer Doctor Mallafre Guasch, 4, 43007 Tarragona (Spain); Calmet, J.; Domenech, S. [Department of Orthopaedic Surgery, Hospital Universitari de Tarragona Joan XXIII, Carrer Doctor Mallafre Guasch, 4, 43007 Tarragona (Spain)

    2003-07-01

    Several skeletal variations of the upper extremity may cause painful conditions or precipitate early degenerative changes, either spontaneously or in response to overuse and trauma. Magnetic resonance imaging has proved particularly useful for accurate interpretation of many of these clinically significant skeletal variations; however, the widespread use of MR imaging may have contributed to over-emphasizing their clinical importance, which is still controversial in many cases. We review, illustrate, and discuss clinically significant skeletal variations of the upper extremity as seen on MR images, particularly those involving the shoulder and the wrist. In the shoulder region, we evaluate variations of acromial and coracoid processes as well as variations and minor dysplastic deformities of the glenoid fossa. We also review different skeletal variations of the carpal region, including ulnar variance, ulnar styloid, lunate morphology, carpal coalition, and carpal accessory ossicles. The role of MR imaging in assessing the clinical importance of such conditions, whether potential, controversial, or well established, is emphasized in this review. (orig.)

  3. Overuse of trauma in sports - clinical signs in the context with modern imaging techniques

    International Nuclear Information System (INIS)

    New insights in the fields of pathology and diagnostic radiology of sports injuries show that the borders between overuse syndromes and trauma are blurred. Techniques of diagnostic imaging are increasingly important for an objective documentation of morphologic changes of the musculoskeletal system. Typical sports-related syndromes exist and their clinical diagnosis is not always easy because pain cannot be located exactly. (author)

  4. Generalized whole-body Patlak parametric imaging for enhanced quantification in clinical PET

    NARCIS (Netherlands)

    Karakatsanis, Nicolas A.; Zhou, Yun; Lodge, Martin A.; Casey, Michael E.; Wahl, Richard L.; Zaidi, Habib; Rahmim, Arman

    2015-01-01

    We recently developed a dynamic multi-bed PET data acquisition framework to translate the quantitative benefits of Patlak voxel-wise analysis to the domain of routine clinical whole-body (WB) imaging. The standard Patlak (sPatlak) linear graphical analysis assumes irreversible PET tracer uptake, ign

  5. Magnetic resonance imaging in radial head fractures: most associated injuries are not clinically relevant

    NARCIS (Netherlands)

    L. Kaas; R.P. van Riet; J.L. Turkenburg; J.P.A.M. Vroemen; C.N. van Dijk; D. Eygendaal

    2011-01-01

    Background: Recent studies report that magnetic resonance imaging (MRI) shows a high incidence of associated injuries in patients with a radial head fracture. This retrospective study describes the clinical relevance of these injuries. Materials and methods: Forty patients with 42 radial head fractu

  6. MALIGNANT PAROTID TUMORS - CLINICAL USE OF MR IMAGING AND HISTOLOGIC CORRELATION

    NARCIS (Netherlands)

    FRELING, NJM; MOLENAAR, WM; VERMEY, A; MOOYAART, EL; PANDERS, AK; ANNYAS, AA; THIJN, CJP

    1992-01-01

    Magnetic resonance (MR) imaging was performed in 116 patients in whom a parotid mass lesion was clinically suspected. Eighty-six patients had benign disease. The 30 patients in whom a malignant tumor was found were further evaluated. To determine which features are characteristic of malignant paroti

  7. Feasibility study of small animal imaging using clinical PET/CT scanner

    Science.gov (United States)

    Hsu, Wen-Lin; Chen, Chia-Lin; Wang, Ze-Jing; Wu, Tung-Hsin; Liu, Dai-Wei; Lee, Jason J. S.

    2007-02-01

    The feasibility of small animal imaging using a clinical positron emission tomography/computed tomography (PET/CT) scanner with [F-18]-fluoro-2-deoxy- D-glucose (FDG) was evaluated. Two protocols in PET/CT system, single-mouse high-resolution mode (SHR) and multi-mouse high throughput mode (MHT) protocol were employed to investigate the ability of the scanner and also explored the performance differences between microPET and clinical PET/CT. In this study, we have found that even the clinical PET/CT scanner could not compete with the microPET scanner, especially in spatial resolution; the high-resolution CT image could advance the anatomical information to sub-millimeter level. Besides, CT-based attenuation correction can improve the image uniformity characteristics and quantification accuracy, and the large bore of a human whole-body scanner broadens the possibility of high throughput studies. Considering all the benefits, clinical PET/CT imaging might be a potential alternative for small animal study.

  8. Molecular imaging in neuroendocrine tumors : Molecular uptake mechanisms and clinical results

    NARCIS (Netherlands)

    Koopmans, Klaas P.; Neels, Oliver N.; Kema, Ido P.; Elsinga, Philip H.; Links, Thera P.; de Vries, Elisabeth G. E.; Jager, Pieter L.

    2009-01-01

    Neuroendocrine tumors can originate almost everywhere in the body and consist of a great variety of subtypes. This paper focuses on molecular imaging methods using nuclear medicine techniques in neuroendocrine tumors, coupling molecular uptake mechanisms of radiotracers with clinical results. A non-

  9. Loop radiofrequency coils for clinical magnetic resonance imaging at 7 TESLA

    NARCIS (Netherlands)

    Kraff, Oliver

    2011-01-01

    To date, the 7 T magnetic resonance imaging (MRI) scanner remains a pure research system and there is still a long way ahead till full clinical integration. Key challenges are the absence of a body transmit radiofrequency (RF) coil as well as of dedicated RF coils in general, short RF wavelengths of

  10. DWI of Prostate Cancer: Optimal b-Value in Clinical Practice

    Directory of Open Access Journals (Sweden)

    Guglielmo Manenti

    2014-01-01

    Full Text Available Aim. To compare the diagnostic performance of diffusion weighted imaging (DWI using b-values of 1000 s/mm2 and 2000 s/mm2 at 3 Tesla (T for the evaluation of clinically significant prostate cancer. Matherials and Methods. Seventy-eight prostate cancer patients underwent a 3T MRI scan followed by radical prostatectomy. DWI was performed using b-values of 0, 1000, and 2000 s/mm2 and qualitatively analysed by two radiologists. ADC maps were obtained at b-values of 1000 and 2000 s/mm2 and quantitatively analyzed in consensus. Results. For diagnosis of 78 prostate cancers the accuracy of DWI for the young reader was significantly greater at b = 2000 s/mm2 for the peripheral zone (PZ but not for the transitional zone (TZ. For the experienced reader, DWI did not show significant differences in accuracy between b-values of 1000 and 2000 s/mm2. The quantitative analysis in the PZ and TZ was substantially superimposable between the two b-values, albeit with a higher accuracy with a b-value of 2000 s/mm2. Conclusions. With a b-value of 2000 s/mm2 at 3T both readers differentiated clinical significant cancer from benign tissue; higher b-values can be helpful for the less experienced readers.

  11. Lateral epicondylitis and beyond: imaging of lateral elbow pain with clinical-radiologic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kotnis, Nikhil A. [McMaster University, Departments of Radiology, Hamilton, ON (Canada); Sheffield Teaching Hospitals, Department of Medical Physics and Medical Imaging, Sheffield (United Kingdom); Chiavaras, Mary M. [McMaster University, Departments of Radiology, Hamilton, ON (Canada); Harish, Srinivasan [McMaster University, Departments of Radiology, Hamilton, ON (Canada); St. Joseph' s Healthcare, Department of Diagnostic Imaging, Hamilton, ON (Canada)

    2012-04-15

    The diagnosis of lateral epicondylitis is often straightforward and can be made on the basis of clinical findings. However, radiological assessment is valuable where the clinical picture is less clear or where symptoms are refractory to treatment. Demographics, aspects of clinical history, or certain physical signs may suggest an alternate diagnosis. Knowledge of the typical clinical presentation and imaging findings of lateral epicondylitis, in addition to other potential causes of lateral elbow pain, is necessary. These include entrapment of the posterior interosseous and lateral antebrachial cutaneous nerves, posterolateral rotatory instability, posterolateral plica syndrome, Panner's disease, osteochondritis dissecans of the capitellum, radiocapitellar overload syndrome, occult fractures and chondral-osseous impaction injuries, and radiocapitellar arthritis. Knowledge of these potential masquerades of lateral epicondylitis and their characteristic clinical and imaging features is essential for accurate diagnosis. The goal of this review is to provide an approach to the imaging of lateral elbow pain, discussing the relevant anatomy, various causes, and discriminating factors, which will allow for an accurate diagnosis. (orig.)

  12. Lateral epicondylitis and beyond: imaging of lateral elbow pain with clinical-radiologic correlation

    International Nuclear Information System (INIS)

    The diagnosis of lateral epicondylitis is often straightforward and can be made on the basis of clinical findings. However, radiological assessment is valuable where the clinical picture is less clear or where symptoms are refractory to treatment. Demographics, aspects of clinical history, or certain physical signs may suggest an alternate diagnosis. Knowledge of the typical clinical presentation and imaging findings of lateral epicondylitis, in addition to other potential causes of lateral elbow pain, is necessary. These include entrapment of the posterior interosseous and lateral antebrachial cutaneous nerves, posterolateral rotatory instability, posterolateral plica syndrome, Panner's disease, osteochondritis dissecans of the capitellum, radiocapitellar overload syndrome, occult fractures and chondral-osseous impaction injuries, and radiocapitellar arthritis. Knowledge of these potential masquerades of lateral epicondylitis and their characteristic clinical and imaging features is essential for accurate diagnosis. The goal of this review is to provide an approach to the imaging of lateral elbow pain, discussing the relevant anatomy, various causes, and discriminating factors, which will allow for an accurate diagnosis. (orig.)

  13. Indications, advantages and limitations of perinatal postmortem imaging in clinical practice

    International Nuclear Information System (INIS)

    Just as there is a range of paediatric imaging techniques available during life, a similar repertoire is available as part of the foetal and perinatal postmortem examination. In this article, we review the literature regarding the diagnostic utility of postmortem radiography, US, CT and MRI in this clinical setting. There is limited direct evidence on the diagnostic utility of any of these techniques, apart from postmortem MRI, which when combined with other noninvasive investigations, has been shown to be highly sensitive and specific for many foetal postmortem diagnoses. The main disadvantages of postmortem MRI include the longer duration of imaging, the need for appropriate training in the interpretation of normal postmortem changes, and possible non-diagnostic imaging examinations in early gestation fetuses. As less-invasive autopsy becomes increasingly available, the true utility of these techniques will evolve, and clinical guidelines for maximal diagnostic yield can be developed. (orig.)

  14. Indications, advantages and limitations of perinatal postmortem imaging in clinical practice

    Energy Technology Data Exchange (ETDEWEB)

    Arthurs, Owen J. [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Radiology, London (United Kingdom); University College London, Institute of Child Health, London (United Kingdom); Taylor, Andrew M. [Great Ormond Street Hospital for Children NHS Foundation Trust, Cardiorespiratory Division, London (United Kingdom); Centre for Cardiovascular Imaging, UCL Institute of Cardiovascular Science, London (United Kingdom); Sebire, Neil J. [University College London, Institute of Child Health, London (United Kingdom); Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Histopathology, London (United Kingdom)

    2015-04-01

    Just as there is a range of paediatric imaging techniques available during life, a similar repertoire is available as part of the foetal and perinatal postmortem examination. In this article, we review the literature regarding the diagnostic utility of postmortem radiography, US, CT and MRI in this clinical setting. There is limited direct evidence on the diagnostic utility of any of these techniques, apart from postmortem MRI, which when combined with other noninvasive investigations, has been shown to be highly sensitive and specific for many foetal postmortem diagnoses. The main disadvantages of postmortem MRI include the longer duration of imaging, the need for appropriate training in the interpretation of normal postmortem changes, and possible non-diagnostic imaging examinations in early gestation fetuses. As less-invasive autopsy becomes increasingly available, the true utility of these techniques will evolve, and clinical guidelines for maximal diagnostic yield can be developed. (orig.)

  15. MALDI mass spectrometry imaging of formalin-fixed paraffin-embedded tissues in clinical research.

    Science.gov (United States)

    Gorzolka, Karin; Walch, Axel

    2014-11-01

    The molecular investigation of archived formalin-fixed, paraffin-embedded (FFPE) tissue samples provides the chance to obtain molecular patterns as indicatives for treatment and clinical end points. MALDI mass spectrometry imaging is capable of localizing molecules like proteins and peptides in tissue sections and became a favorite platform for the targeted and non-targeted approaches, especially in clinical investigations for biomarker research. In FFPE tissues the recovery of proteomic information is constrained by fixation-induced cross-links of proteins. The promising new insights obtained from FFPE in combination with the comprehensive patients' data caused much progress in the optimization of MS imaging protocols to investigate FFPE samples. This review presents the past and current research in MALDI MS imaging of FFPE tissues, demonstrating the improvement of analyses, their actual limitations, but also the promising future perspectives for histopathological and tissue-based research.

  16. 骨和软组织肿瘤的3.0T磁共振磷谱变化研究%Changes of 3-tesla 31P-MR spectroscopy of bone and soft tissue tumors

    Institute of Scientific and Technical Information of China (English)

    齐滋华; 李传福; 马祥兴; 李振峰; 张凯; 于德新

    2009-01-01

    Objective To study the characteristic changes of 31P-MR spectroscopy of bone and soft tissue tumors. Methods 41 patients were examined by phosphorus surface coil of 3 tesla MR machine, including 18 benign tumor foci and 28 malignant foci, and adjacent normal muscles. The areas under the peaks of various metabolites in the spectra were measured, including phosphomonoester(PME), inorganic phosphours (Pi), phosphodiester(PDE), phosphocreatine ( Pcr ), adenosine triphosphate (ATP) γ, α, β. The ratios of the metabolites to β-ATP, NTP and Pcr were calculated. Intracellular pH was calculated according to the chemical shift change of Pi relative to Per. Results The ratios of Pcr/PME and PME/NTP in benign and malignant tumor groups were significantly different from those of the normal group ( P < 0.05). Between benign and malignant tumor groups, the ratios of PME/β-ATP and PME/NTP were significantly different (P < 0.05). Conclusion Pcr/PME and PME/NTP are potential diagnostic indexes of bone and soft tissue tumors. PME/β-ATP and PME/NTP are potential indexes of differential diagnosis of bone and soft tissue tumors.%目的 探讨骨和软组织肿瘤磁共振磷谱(31P-MRS)的变化特点.方法 对41例经病理证实的骨和软组织肿瘤患者的18个良性肿瘤病灶、28个恶性肿瘤病灶及其相邻部位正常肌肉组织,应用3.0T MR机进行31P-MRS分析,测量波谱中磷酸单酯(PME)、无机磷(Pi)、磷酸二酯(PDE)、磷酸肌酸(Pcr)、三磷酸腺苷γ-峰(γ-ATP)、α-峰(α-ATP)和β-峰(β-ATP)的峰下面积.分别以β-ATP、三磷酸核苷(NTP)和Pcr为参照,计算各代谢产物的相对比值.根据Pi相对于Pcr化学位移的变化计算细胞内pH值.结果 良、恶性肿瘤组中Pcr/PME、PME/NTP与正常对照组比较,差异均有统计学意义(P<0.05).良、恶性肿瘤组中PME/β-ATP与PME/NTP比较,差异有统计学意义(P<0.05).结论 Pcr/PME和PME/NTP是诊断骨和软组织肿瘤的潜在指标,PME/β-ATP和PME/NTP是

  17. PET in tumor imaging: research only or a cost effective clinical tool?

    International Nuclear Information System (INIS)

    PET imaging has for many years been a versatile tool for non-invasive imaging of neuro-physiology and, indeed, whole body physiology. Quantitative PET imaging of trace amounts of radioactivity is scientifically elegant and can be very complex. This lecture focuses on whether and where this test is clinically useful. Because of the research tradition, PET imaging has been perceived as an 'expensive' test, as it costs more per scan than CT and MRI scans at most institutions. Such a superficial analysis is incorrect, however, as it is increasingly recognized that imaging costs, which in some circumstances will be increased by the use of PET, are only a relatively small component of patient care costs. Thus, PET may raise imaging costs and the number of imaging procedures in some settings, though PET may reduce imaging test numbers in other settings. However, the analysis must focus on the total costs of patient management. Analyses focused on total patient care costs, including cost of hospitalization and cost surgery as well as imaging costs, have shown that PET can substantially reduce total patient care costs in several settings. This is achieved by providing a more accurate diagnosis, and thus having fewer instances of an incorrect diagnosis resulting in subsequent inappropriate surgery or investigations. Several institutions have shown scenarios in which PET for tumor imaging is cost effective. While the specific results of the analyses vary based on disease prevalence and cost input values for each procedure, as well as the projected performance of PET, the similar results showing total care cost savings in the management of several common cancers, strongly supports the rational for the use of PET in cancer management. In addition, promising clinical results are forthcoming in several other illnesses, suggesting PET will have broader utility than these uses, alone. Thus, while PET is an 'expensive' imaging procedure and has considerable utility as a research

  18. Characterization of the onboard imaging unit for the first clinical magnetic resonance image guided radiation therapy system

    International Nuclear Information System (INIS)

    Purpose: To characterize the performance of the onboard imaging unit for the first clinical magnetic resonance image guided radiation therapy (MR-IGRT) system. Methods: The imaging performance characterization included four components: ACR (the American College of Radiology) phantom test, spatial integrity, coil signal to noise ratio (SNR) and uniformity, and magnetic field homogeneity. The ACR phantom test was performed in accordance with the ACR phantom test guidance. The spatial integrity test was evaluated using a 40.8 × 40.8 × 40.8 cm3 spatial integrity phantom. MR and computed tomography (CT) images of the phantom were acquired and coregistered. Objects were identified around the surfaces of 20 and 35 cm diameters of spherical volume (DSVs) on both the MR and CT images. Geometric distortion was quantified using deviation in object location between the MR and CT images. The coil SNR test was performed according to the national electrical manufacturers association (NEMA) standards MS-1 and MS-9. The magnetic field homogeneity test was measured using field camera and spectral peak methods. Results: For the ACR tests, the slice position error was less than 0.10 cm, the slice thickness error was less than 0.05 cm, the resolved high-contrast spatial resolution was 0.09 cm, the resolved low-contrast spokes were more than 25, the image intensity uniformity was above 93%, and the percentage ghosting was less than 0.22%. All were within the ACR recommended specifications. The maximum geometric distortions within the 20 and 35 cm DSVs were 0.10 and 0.18 cm for high spatial resolution three-dimensional images and 0.08 and 0.20 cm for high temporal resolution two dimensional cine images based on the distance-to-phantom-center method. The average SNR was 12.0 for the body coil, 42.9 for the combined torso coil, and 44.0 for the combined head and neck coil. Magnetic field homogeneities at gantry angles of 0°, 30°, 60°, 90°, and 120° were 23.55, 20.43, 18.76, 19

  19. Characterization of the onboard imaging unit for the first clinical magnetic resonance image guided radiation therapy system

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yanle, E-mail: Hu.Yanle@mayo.edu [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 and Department of Radiation Oncology, Mayo Clinic in Arizona, Phoenix, Arizona 85054 (United States); Rankine, Leith; Green, Olga L.; Kashani, Rojano; Li, H. Harold; Li, Hua; Rodriguez, Vivian; Santanam, Lakshmi; Wooten, H. Omar; Mutic, Sasa [Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States); Nana, Roger; Shvartsman, Shmaryu; Victoria, James; Dempsey, James F. [ViewRay, Inc., Oakwood Village, Ohio 44146 (United States)

    2015-10-15

    Purpose: To characterize the performance of the onboard imaging unit for the first clinical magnetic resonance image guided radiation therapy (MR-IGRT) system. Methods: The imaging performance characterization included four components: ACR (the American College of Radiology) phantom test, spatial integrity, coil signal to noise ratio (SNR) and uniformity, and magnetic field homogeneity. The ACR phantom test was performed in accordance with the ACR phantom test guidance. The spatial integrity test was evaluated using a 40.8 × 40.8 × 40.8 cm{sup 3} spatial integrity phantom. MR and computed tomography (CT) images of the phantom were acquired and coregistered. Objects were identified around the surfaces of 20 and 35 cm diameters of spherical volume (DSVs) on both the MR and CT images. Geometric distortion was quantified using deviation in object location between the MR and CT images. The coil SNR test was performed according to the national electrical manufacturers association (NEMA) standards MS-1 and MS-9. The magnetic field homogeneity test was measured using field camera and spectral peak methods. Results: For the ACR tests, the slice position error was less than 0.10 cm, the slice thickness error was less than 0.05 cm, the resolved high-contrast spatial resolution was 0.09 cm, the resolved low-contrast spokes were more than 25, the image intensity uniformity was above 93%, and the percentage ghosting was less than 0.22%. All were within the ACR recommended specifications. The maximum geometric distortions within the 20 and 35 cm DSVs were 0.10 and 0.18 cm for high spatial resolution three-dimensional images and 0.08 and 0.20 cm for high temporal resolution two dimensional cine images based on the distance-to-phantom-center method. The average SNR was 12.0 for the body coil, 42.9 for the combined torso coil, and 44.0 for the combined head and neck coil. Magnetic field homogeneities at gantry angles of 0°, 30°, 60°, 90°, and 120° were 23.55, 20.43, 18.76, 19

  20. Clinical PET/MR Imaging in Dementia and Neuro-Oncology.

    Science.gov (United States)

    Henriksen, Otto M; Marner, Lisbeth; Law, Ian

    2016-10-01

    The introduction of hybrid PET/MRI systems allows simultaneous multimodality image acquisition of high technical quality. This technique is well suited for the brain, and particularly in dementia and neuro-oncology. In routine use combinations of well-established MRI sequences and PET tracers provide the most optimal and clinically valuable protocols. For dementia the [18F]-fluorodeoxyglucose (FDG) has merit with a simultaneous four sequence MRI protocol of 20 min supported by supplementary statistical reading tools and quantitative measurements of the hippocampal volume. Clinical PET/MRI using [18F]-fluoro-ethyl-tyrosine (FET) also abide to the expectations of the adaptive and versatile diagnostic tool necessary in neuro-oncology covering both simple 20 min protocols for routine treatment surveillance and complicated 90 min brain and spinal cord protocols in pediatric neuro-oncology under general anesthesia. The clinical value of adding advanced MRI sequences in multiparametric imaging setting, however, is still undocumented. PMID:27593248

  1. The image quality of ion computed tomography at clinical imaging dose levels

    International Nuclear Information System (INIS)

    Purpose: Accurately predicting the range of radiotherapy ions in vivo is important for the precise delivery of dose in particle therapy. Range uncertainty is currently the single largest contribution to the dose margins used in planning and leads to a higher dose to normal tissue. The use of ion CT has been proposed as a method to improve the range uncertainty and thereby reduce dose to normal tissue of the patient. A wide variety of ions have been proposed and studied for this purpose, but no studies evaluate the image quality obtained with different ions in a consistent manner. However, imaging doses ion CT is a concern which may limit the obtainable image quality. In addition, the imaging doses reported have not been directly comparable with x-ray CT doses due to the different biological impacts of ion radiation. The purpose of this work is to develop a robust methodology for comparing the image quality of ion CT with respect to particle therapy, taking into account different reconstruction methods and ion species. Methods: A comparison of different ions and energies was made. Ion CT projections were simulated for five different scenarios: Protons at 230 and 330 MeV, helium ions at 230 MeV/u, and carbon ions at 430 MeV/u. Maps of the water equivalent stopping power were reconstructed using a weighted least squares method. The dose was evaluated via a quality factor weighted CT dose index called the CT dose equivalent index (CTDEI). Spatial resolution was measured by the modulation transfer function. This was done by a noise-robust fit to the edge spread function. Second, the image quality as a function of the number of scanning angles was evaluated for protons at 230 MeV. In the resolution study, the CTDEI was fixed to 10 mSv, similar to a typical x-ray CT scan. Finally, scans at a range of CTDEI’s were done, to evaluate dose influence on reconstruction error. Results: All ions yielded accurate stopping power estimates, none of which were statistically

  2. The image quality of ion computed tomography at clinical imaging dose levels

    Energy Technology Data Exchange (ETDEWEB)

    Hansen, David C., E-mail: dch@oncology.au.dk [Department of Experimental Clinical Oncology, Aarhus University Hospital, 8000 Aarhus (Denmark); Bassler, Niels [Department of Physics and Astronomy, Aarhus University, 8000 Aarhus (Denmark); Sørensen, Thomas Sangild [Department of Computer Science, Aarhus University, 8000 Aarhus, Denmark and Department of Clinical Medicine, Aarhus University, 8000 Aarhus (Denmark); Seco, Joao [Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School,Boston, Massachusetts 02114 (United States)

    2014-11-01

    Purpose: Accurately predicting the range of radiotherapy ions in vivo is important for the precise delivery of dose in particle therapy. Range uncertainty is currently the single largest contribution to the dose margins used in planning and leads to a higher dose to normal tissue. The use of ion CT has been proposed as a method to improve the range uncertainty and thereby reduce dose to normal tissue of the patient. A wide variety of ions have been proposed and studied for this purpose, but no studies evaluate the image quality obtained with different ions in a consistent manner. However, imaging doses ion CT is a concern which may limit the obtainable image quality. In addition, the imaging doses reported have not been directly comparable with x-ray CT doses due to the different biological impacts of ion radiation. The purpose of this work is to develop a robust methodology for comparing the image quality of ion CT with respect to particle therapy, taking into account different reconstruction methods and ion species. Methods: A comparison of different ions and energies was made. Ion CT projections were simulated for five different scenarios: Protons at 230 and 330 MeV, helium ions at 230 MeV/u, and carbon ions at 430 MeV/u. Maps of the water equivalent stopping power were reconstructed using a weighted least squares method. The dose was evaluated via a quality factor weighted CT dose index called the CT dose equivalent index (CTDEI). Spatial resolution was measured by the modulation transfer function. This was done by a noise-robust fit to the edge spread function. Second, the image quality as a function of the number of scanning angles was evaluated for protons at 230 MeV. In the resolution study, the CTDEI was fixed to 10 mSv, similar to a typical x-ray CT scan. Finally, scans at a range of CTDEI’s were done, to evaluate dose influence on reconstruction error. Results: All ions yielded accurate stopping power estimates, none of which were statistically

  3. Disease-specific target gene expression profiling of molecular imaging probes: database development and clinical validation.

    Science.gov (United States)

    Chan, Lawrence Wing-Chi; Ngo, Connie Hiu-Ching; Wang, Fengfeng; Zhao, Moss Y; Zhao, Mengying; Law, Helen Ka-Wai; Wong, Sze Chuen Cesar; Yung, Benjamin Yat-Ming

    2014-01-01

    Molecular imaging probes can target abnormal gene expression patterns in patients and allow early diagnosis of disease. For selecting a suitable imaging probe, the current Molecular Imaging and Contrast Agent Database (MICAD) provides descriptive and qualitative information on imaging probe characteristics and properties. However, MICAD does not support linkage with the expression profiles of target genes. The proposed Disease-specific Imaging Probe Profiling (DIPP) database quantitatively archives and presents the gene expression profiles of targets across different diseases, anatomic regions, and subcellular locations, providing an objective reference for selecting imaging probes. The DIPP database was validated with a clinical positron emission tomography (PET) study on lung cancer and an in vitro study on neuroendocrine cancer. The retrieved records show that choline kinase beta and glucose transporters were positively and significantly associated with lung cancer among the targets of 11C-choline and [18F]fluoro-2-deoxy-2-d-glucose (FDG), respectively. Their significant overexpressions corresponded to the findings that the uptake rate of FDG increased with tumor size but that of 11C-choline remained constant. Validated with the in vitro study, the expression profiles of disease-associated targets can indicate the eligibility of patients for clinical trials of the treatment probe. A Web search tool of the DIPP database is available at http://www.polyu.edu.hk/bmi/dipp/. PMID:25022454

  4. Self-image and eating disorder symptoms in normal and clinical adolescents.

    Science.gov (United States)

    Forsén Mantilla, Emma; Bergsten, Katja; Birgegård, Andreas

    2014-01-01

    Eating disorders (ED) are psychiatric disorders of multifactorial origin, predominantly appearing in adolescence. Negative self-image is identified as risk factor, but the association between self-image and ED in adolescents or sex differences regarding such associations remains unclear. The study aimed to investigate the relationship between specific self-image aspects and ED symptoms in normal and clinical adolescents, including sex differences. Participants included 855 ED patients (girls=813, boys=42) and 482 normal adolescents (girls=238, boys=244), 13-15 years. Stepwise regression demonstrated strong associations between self-image and ED in normal adolescents (girls: R(2)=.31, boys: R(2)=.08), and stronger associations in patients (girls: R(2)=.64, boys: R(2)=.69). Qualitative sex differences were observed in patients. Connections between specific self-image aspects and ED have implications for clinical management of ED. The strong link between self-image variables and ED symptoms in normal girls, but not boys, is discussed in terms of the continuity-discontinuity hypothesis. PMID:24411765

  5. Clinical usefulness of cardiac cine magnetic resonance imaging in patients with atrial fibrillation

    International Nuclear Information System (INIS)

    We studied the clinical usefulness of cine mode magnetic resonance (MR) imaging in patients with atrial fibrillation (AF) from aspects of image quality and cardiac function. The signal-to-noise (S/N) ratio in the myocardium was significantly (p<0.05) lower in patients with AF than those with normal sinus rhythm. Two radiologists who did not know any patient's information evaluated the image quality visually by marking method on a scale of 12 points. There was no difference of image quality between the two groups. The standard deviation of R-R interval was significantly (r=-0.92, p<0.001) correlated with the S/N ratio in myocardium. Consequently, it was not favorable to estimate visually cardiac cine MR image in patients with AF, when standard deviation of R-R interval was large. The left ventricular (LV) end diastolic, end systolic and stroke volumes and ejection fraction were closely (r=0.82∼0.95, p<0.05∼0.001) correlated between MR imaging and M-mode echocardiography, respectively. The ability to detect left side valvular regurgitation was almost equal in both MR imaging and color Doppler echocardiography. This result was coincided to previous papers in patients with normal sinus rhythm. In conclusion, cine mode MR imaging was also useful to analyze cardiac function and detect valvular regurgitation in patients with AF. (author)

  6. Cross-sectional imaging for diagnosis and clinical outcome prediction of acute basilar artery thrombosis

    International Nuclear Information System (INIS)

    Basilar artery occlusion is a potentially fatal condition and imaging findings can be subtle. Prompt diagnosis is vital, as recognition may lead to therapeutic recanalization that may improve functional outcome and survival. Furthermore, cross-sectional imaging signs may help predict eventual outcome and, therefore, guide which patients should be subjected to aggressive treatment. Computed tomography (CT) signs include a hyperdense basilar artery that has a high specificity, accuracy, positive and negative predictive value. Evidence regarding the prognostic significance of the hyperdense basilar artery sign is conflicting. Early magnetic resonance imaging (MRI) features include loss of flow void, seen as increased signal intensity within the basilar artery on T2-weigted images and identification of acute thrombus, seen as intermediate signal on T1-weighted images. MRI sequences are more sensitive for early detection of acute ischaemia or infarction, ideally with diffusion-weighted imaging (DWI). Both CT and MR angiography are sensitive for detection of acute thrombus, seen as a filling defect or occlusion. These are the non-invasive imaging techniques of choice to confirm diagnosis, with perhaps the speed and accessibility of CT angiography resulting in this technique being valuable in the acute setting. Several new scoring systems based on arterial segmentation rather than global volume assessment using CT angiography source images and DWI have shown early promise in the prediction of eventual clinical outcome in order to isolate those patients who may benefit from therapeutic recanalization.

  7. Intramuscular leukemic relapse: clinical signs and imaging findings. A multicentric analysis

    International Nuclear Information System (INIS)

    Leukemia is a group of malignant diseases involving peripheral blood and bone marrow. Extramedullary tumor manifestation in leukemia can also occur. They more often involve lymph nodes, skin, and bones. Intramuscular leukemic relapse (ILR) is very unusual. The aim of this analysis was to summarize the reported data regarding clinical signs and radiological features of ILR. The PubMed database was searched for publications related to ILR. After an analysis of all identified articles, 20 publications matched the inclusion criteria. The authors of the 20 publications were contacted and provided imaging of their cases for review. The following were recorded: age, gender, primary diagnosis, clinical signs, pattern, localization and size of the intramuscular leukemic relapse. Images of 16 patients were provided [8 computer tomographic (CT) images and 15 magnetic resonance images, MRI]. Furthermore, one patient with ILR was identified in our institutional database. Therefore, images of 17 patients were available for further analysis. Overall, 32 cases with ILR were included in the analysis. In most cases acute myeloid leukemia was diagnosed. Most ILRs were localized in the extremities (44 %) and in the extraocular muscles (44 %). Clinically, ILR manifested as local pain, swelling and muscle weakness. Radiologically, ILR presented most frequently with diffuse muscle infiltration. On postcontrast CT/MRI, most lesions demonstrated homogeneous enhancement. ILRs were hypo-/isointense on T1w and hyperintense on T2w images. ILR manifests commonly as focal pain, swelling and muscle weakness. ILR predominantly involved the extraocular musculature and the extremities. Radiologically, diffuse muscle infiltration was the most common imaging finding. (orig.)

  8. Intramuscular leukemic relapse: clinical signs and imaging findings. A multicentric analysis

    Energy Technology Data Exchange (ETDEWEB)

    Surov, Alexey [Martin Luther University Halle-Wittenberg, Department of Radiology, Halle (Germany); University of Leipzig, Department of Diagnostic and Interventional Radiology, Leipzig (Germany); Kiratli, Hayyam [Hacettepe University School of Medicine, Department of Ophthalmology, Ankara (Turkey); Im, Soo Ah [Seoul St. Mary' s Hospital, Department of Radiology, Seoul (Korea, Republic of); Manabe, Yasuhiro [National Hospital Organization Okayama Medical Center, Department of Neurology, Okayama (Japan); O' Neill, Alibhe; Shinagare, Atul B. [Brigham and Women' s Hospital, Department of Radiology, Boston, MA (United States); Spielmann, Rolf Peter [Martin Luther University Halle-Wittenberg, Department of Radiology, Halle (Germany)

    2014-09-26

    Leukemia is a group of malignant diseases involving peripheral blood and bone marrow. Extramedullary tumor manifestation in leukemia can also occur. They more often involve lymph nodes, skin, and bones. Intramuscular leukemic relapse (ILR) is very unusual. The aim of this analysis was to summarize the reported data regarding clinical signs and radiological features of ILR. The PubMed database was searched for publications related to ILR. After an analysis of all identified articles, 20 publications matched the inclusion criteria. The authors of the 20 publications were contacted and provided imaging of their cases for review. The following were recorded: age, gender, primary diagnosis, clinical signs, pattern, localization and size of the intramuscular leukemic relapse. Images of 16 patients were provided [8 computer tomographic (CT) images and 15 magnetic resonance images, MRI]. Furthermore, one patient with ILR was identified in our institutional database. Therefore, images of 17 patients were available for further analysis. Overall, 32 cases with ILR were included in the analysis. In most cases acute myeloid leukemia was diagnosed. Most ILRs were localized in the extremities (44 %) and in the extraocular muscles (44 %). Clinically, ILR manifested as local pain, swelling and muscle weakness. Radiologically, ILR presented most frequently with diffuse muscle infiltration. On postcontrast CT/MRI, most lesions demonstrated homogeneous enhancement. ILRs were hypo-/isointense on T1w and hyperintense on T2w images. ILR manifests commonly as focal pain, swelling and muscle weakness. ILR predominantly involved the extraocular musculature and the extremities. Radiologically, diffuse muscle infiltration was the most common imaging finding. (orig.)

  9. Construction and characterisation of MRI coils for vessel wall imaging at 7 tesla

    OpenAIRE

    Papoutsis, Konstantinos; Jezzard, Peter; Payne, Stephen J.; Edwards, David,

    2014-01-01

    Atherosclerotic plaques in the bifurcation of the carotid artery vessels can pose a significant stroke risk from stenosis, thrombosis and emboli, or plaque rupture. However, the possibility of the latter depends on the structure of the plaque and its stability. So far, the assessment of such depositions, and the evaluation of the risk they pose, is not satisfactory with 3 Tesla black blood imaging. It is expected that the SNR increase at 7 Tesla, together with an appropriate and patient-safe ...

  10. Magnetic field perturbation in proton MR imaging - A study of a contrast agent and of distortions due to metallic implants

    International Nuclear Information System (INIS)

    Perturbations of the static magnetic field in proton MR imaging (NMR imaging, MRI, MRT) result in image distortion and/or signal loss. An investigation of a superparamagnetic contrast agent for MR imaging has been performed. Magnetite particles were embedded in biodegradable starch spheres with a diameter of one micrometer. Animal experiments showed that the agent was quickly accumulated in the reticulo-endothelial system (RES), causing a decrease in signal intensity in this region. Diffusion within the locally generated magnetic field perturbation is responsible for signal loss in spin-echo images. Furthermore, the magnetic properties of various aneurysm clips were investigated to determine which clips could be used safely in a clinical MR investigation. MR artifacts caused by the metallic clips were studied using a geometric phantom. Non-ferromagnetic clips were concluded to be safe for examinations with medium field (0.3 tesla) MR imaging systems. A comparison study between MR and CT was performed on patients harbouring intracranial, nonferromagnetic aneurysm clips. The artifacts close to the clips were equally serve for MR and CT, but at some distance, the MR images were much less affected than the CT images. Finally, a computer program capable of simulating any realistic MR imaging situation has been developed. Raw data matrices are obtained by solving the Bloch equations. Corrections for intravascular spin behaviour have been implemented together with efficient algorithms. A quantitative investigation of signal displacement and signal loss, caused by small metallic implants, has been performed by computer simulation. An exact expression for the magnetic field outside a homogeneous ellipsoid in an external magnetic field has been derived. Distortions in MR images, caused by perturbing ellipsoids of different shapes and orientations, were studied. (30 refs.) (au)

  11. Disease activity in Graves' ophthalmopathy: diagnosis with orbital MR imaging and correlation with clinical score.

    Science.gov (United States)

    Tortora, Fabio; Cirillo, Mario; Ferrara, Marco; Belfiore, Maria Paola; Carella, Carlo; Caranci, Ferdinando; Cirillo, Sossio

    2013-10-01

    In Graves' ophthalmopathy (GO) it is important to distinguish acute inflammation at an early stage, responsive to immunosuppressive treatment, from inactive fibrotic end stage disease, unresponsive to the same treatment. The purpose of this study was to identify the most relevant signal intensities on orbital MR imaging with contrast administration both to classify patients according to their clinical activity score (defined by a cut-off value of 3) and to make a prediction of patient's CAS. Such threshold was considered as widely used in literature. Sixteen consecutive patients with a diagnosis of GO in different phases of thyroid disease based on clinical and orbital MR imaging signs, and six normal volunteers were examined. Orbital MR imaging was performed on a 1.5 Tesla MR Unit. MR scans were assessed by an experienced neuroradiologist, blinded to the clinical examinations. We found a statistical correlation between CAS and both STIR and contrast enhanced T1-weighted sequences. There was also a statistically significant correlation between STIR and contrast-enhanced T1 images disclosing the possibility of avoiding the injection of contrast medium. Our study proved that signal intensity values on STIR sequence increase in the inflammatory oedematous phase of disease. We confirmed the correlation between signal intensities on this sequence and CAS, showing an increase in signal intensity proportional to the CAS value. So we validated MRI use to establish the activity phase of disease more sensitively than CAS alone.

  12. Pelvic Inflammatory Disease: Multimodality Imaging Approach with Clinical-Pathologic Correlation.

    Science.gov (United States)

    Revzin, Margarita V; Mathur, Mahan; Dave, Haatal B; Macer, Matthew L; Spektor, Michael

    2016-01-01

    Pelvic inflammatory disease (PID) is a common medical problem, with almost 1 million cases diagnosed annually. Historically, PID has been a clinical diagnosis supplemented with the findings from ultrasonography (US) or magnetic resonance (MR) imaging. However, the diagnosis of PID can be challenging because the clinical manifestations may mimic those of other pelvic and abdominal processes. Given the nonspecific clinical manifestations, computed tomography (CT) is commonly the first imaging examination performed. General CT findings of early- and late-stage PID include thickening of the uterosacral ligaments, pelvic fat stranding with obscuration of fascial planes, reactive lymphadenopathy, and pelvic free fluid. Recognition of these findings, as well as those seen with cervicitis, endometritis, acute salpingitis, oophoritis, pyosalpinx, hydrosalpinx, tubo-ovarian abscess, and pyometra, is crucial in allowing prompt and accurate diagnosis. Late complications of PID include tubal damage resulting in infertility and ectopic pregnancy, peritonitis caused by uterine and/or tubo-ovarian abscess rupture, development of peritoneal adhesions resulting in bowel obstruction and/or hydroureteronephrosis, right upper abdominal inflammation (Fitz-Hugh-Curtis syndrome), and septic thrombophlebitis. Recognition of these late manifestations at CT can also aid in proper patient management. At CT, careful assessment of common PID mimics, such as endometriosis, adnexal torsion, ruptured hemorrhagic ovarian cyst, adnexal neoplasms, appendicitis, and diverticulitis, is important to avoid misinterpretation, delay in management, and unnecessary surgery. Correlation with the findings from complementary imaging examinations, such as US and MR imaging, is useful for establishing a definitive diagnosis. (©)RSNA, 2016. PMID:27618331

  13. Myocardial strain imaging: how useful is it in clinical decision making?

    Science.gov (United States)

    Smiseth, Otto A; Torp, Hans; Opdahl, Anders; Haugaa, Kristina H; Urheim, Stig

    2016-04-14

    Myocardial strain is a principle for quantification of left ventricular (LV) function which is now feasible with speckle-tracking echocardiography. The best evaluated strain parameter is global longitudinal strain (GLS) which is more sensitive than left ventricular ejection fraction (LVEF) as a measure of systolic function, and may be used to identify sub-clinical LV dysfunction in cardiomyopathies. Furthermore, GLS is recommended as routine measurement in patients undergoing chemotherapy to detect reduction in LV function prior to fall in LVEF. Intersegmental variability in timing of peak myocardial strain has been proposed as predictor of risk of ventricular arrhythmias. Strain imaging may be applied to guide placement of the LV pacing lead in patients receiving cardiac resynchronization therapy. Strain may also be used to diagnose myocardial ischaemia, but the technology is not sufficiently standardized to be recommended as a general tool for this purpose. Peak systolic left atrial strain is a promising supplementary index of LV filling pressure. The strain imaging methodology is still undergoing development, and further clinical trials are needed to determine if clinical decisions based on strain imaging result in better outcome. With this important limitation in mind, strain may be applied clinically as a supplementary diagnostic method.

  14. Development of X-ray dark-field imaging towards clinical application

    Institute of Scientific and Technical Information of China (English)

    ANDO Masami; RUBENSTEIN Edward; ROBERSON Joseph; SHIMAO Daisuke; SUGIYAMA Hiroshi; TAKEDA Ken; UENO Ei; WADA Hiroshi; HASHIMOTO Eiko; HASHIZUME Hiroyuki; HYODO Kazuyuki; INOUE Hajime; ISHIKAWA Tetsuya; KUNISADA Toshiyuki; MAKSIMENKO Anton; PATTANASIRIWISAWA Wanwisa

    2004-01-01

    Review of X-ray dark-field imaging under development is presented. Its goal is its application to clinical diagnosis of organs that have been invisible by the ordinary techniques. In order to clinically visualize tissues in detail one needs high contrast and high spatial resolution say ~50 μm. This X-ray optics comprises a Bragg asymmetric monochro-collimator and a Bragg case or a Laue case filter with capability of analyzing angle in a parallel position. Their diffraction index is 4,4,0 and the X-ray energy 35 keV (λ= 0.0354 nm). The filter has 0.6 mm thickness in the Bragg case or 1.075 mm or 2.15 mm thickness in the Laue case. Under this condition only the refracted X-rays from object can transmit through the filter while the beam that may receive absorption and/or phase change will not. Soft tissues at human joints thus taken show high contrast images so that the DFI is promising for clinical diagnosis. Preliminary X-ray absorption images of another clinical candidates of ear bones are also shown.

  15. Cervical spine degenerative diseases: An evaluation of clinical and imaging features in surgical decisions

    Energy Technology Data Exchange (ETDEWEB)

    Soo, M.; Tran-Dinh, H.D.; Quach, T.; Downey, J.; Pohlmann, S. [Westmead Hospital, Westmead, NSW (Australia). Department of Radiology; Dorsch, N.W.C. [Westmead Hospital, Westmead, NSW (Australia). Department of Neurosurgery

    1997-11-01

    In clinically severe cervical spondylosis, imaging plays a vital role in surgical decisions. A prime factor is acquired canal stenosis with cord compression. To validate this concept, the clinical and imaging features of 20 patients with spondylitic myelopathy and 24 with radiculopathy were retrospectively reviewed. All had computed tomographic myelography (CTM) as part of their clinical work-up. The patients` clinical severity was graded as mild, moderate and severe; the age, length of illness and a history of eventual surgery or otherwise were recorded. At the level of maximum compression the following parameters were obtained from the axial CTM images: surface area and ratio of the anteroposterior to the transverse diameter of the cord; subarachnoid space and vertebral canal areas. Data were statistically analysed. A significant association exists between surgery and increasing severity of symptoms (P=0.04), and advancing age (P=0.01). These associations hold true for myelopathy and radiculopathy. A strong association is present between surgery and the surface area of the cord (P=0.01), being applicable to myelopathy only. The other parameters show no association with surgical decisions. It is concluded that with myelopathy a narrow cord area at the level of maximum compression, and moderate-severe functional impairment are indicators for surgical intervention. (authors). 22 refs., 3 tabs., 3 figs.

  16. A review of methods of clinical image quality evaluation in mammography

    International Nuclear Information System (INIS)

    Purpose: Consistency in evaluation of mammography images in research and clinical practice is dependent on a standardised clinical image quality evaluation system. Currently two such systems are available-one developed by the American College of Radiology (ACR) and the other by the European Commission (EU guidelines). The purpose of this study was to review mammography clinical evaluation methods in research studies and their adherence to these systems. Method: A total of 23 research articles were reviewed from the period 2000-2006, 11 of these studies used digital images. The focus of the review was the criteria and rating scales used. Results: Only 5 studies used either the ACR (3) or EU guidelines (2). The remainder included aspects of these systems together with a range of other criteria and rating scales. Variation was found in the categories of criteria used, number of criteria, the descriptors of the criteria and the instructions used to evaluate the criteria. Instructions were frequently not specific and open to individual interpretation. Although breast density is an important criterion of image quality and contributes to perception of breast lesions, inclusion of this criterion was not universal, and even when used the area of breast density to be evaluated was not identified, thus enhancing inter-observer variability. Scales that were absolute or relative were used for evaluation, all of which incorporated inconsistent numbers of steps. Conclusion: Low adherence to ACR and EU Guidelines has resulted in considerable variation in the evaluation methods used in research studies. The implications of this variability are considerable both for evaluation of image quality in research outcomes and clinical practice.

  17. Clinical multi-colour fluorescence imaging of malignant tumours - initial experience

    Energy Technology Data Exchange (ETDEWEB)

    Svanberg, K.; Wang, I. [Lund Univ. Hospital (Sweden). Lund Medical Laser Centre]|[Lund Univ. Hospital (Sweden). Dept. of Oncology; Colleen, S. [Lund Univ. Hospital (Sweden). Lund Medical Laser Centre]|[Lund Univ. Hospital (Sweden). Dept. of Urology; Idvall, I. [Lund Univ. Hospital (Sweden). Lund Medical Laser Centre]|[Lund Univ. Hospital (Sweden). Dept. of Pathology; Ingvar, C. [Lund Univ. Hospital (Sweden). Lund Medical Laser Centre]|[Lund Univ. Hospital (Sweden). Dept. of Surgery; Rydell, R. [Lund Univ. Hospital (Sweden). Lund Medical Laser Centre]|[Lund Univ. Hospital (Sweden). Dept. of Oto-Rhino-Laryngology; Jocham, D. [Luebeck Univ. (Germany). Abt. fuer Urologie; Diddens, H. [Luebeck Univ. (Germany). Medizinisches Laser Zentrum; Bown, S.; Gregory, G. [National Medical Laser Centre, Dept. of Surgery, Rayne Inst., London (United Kingdom); Montan, S. [Spectraphos AB, Ideon, Lund (Sweden); Andersson-Engels, S.; Svanberg, S. [Lund Univ. Hospital (Sweden). Lund Medical Laser Centre]|[Lund Inst. of Technology (Sweden). Dept. of Physics

    1998-01-01

    The purpose of this study was to present a new technique for non-invasive tumour detection based on tissue fluorescence imaging. A clinically adapted multi-colour fluorescence system was employed in the real-time imaging of malignant tumours of the skin, breast, head and neck region, and urinary bladder. Tumour detection was based on the contrast displayed in fluorescence between normal and malignant tissue, related to the selective uptake of tumour-marking agents and natural chromophore differences between various tissues. In order to demarcate basal cell carcinomas of the skin, ALA was applied topically 4-6 h before the fluorescence investigation. For urinary bladder tumour visualisation, ALA was instilled into the bladder 1-2 h prior to the study. Malignant and premalignant lesions in the head and neck region were imaged after i.v. injection of HPD (Photofrin). The tumour imaging system was coupled to an endoscope. Fluorescence light emission from the tissue surface was induced with 100-ns-long optical pulses at 390 nm, generated from a frequency-doubled alexandrite laser. With the use of special image-splitting optics, the tumour fluorescence, intensified in a micro-channel plate, was imaged in 3 selected wavelength bands. These 3 images were processed together to form a new optimised-contrast image of the tumour. This image, updated at a rate of about 3 frames/s was mixed with a normal colour video image of the tissue. A clear demarcation from normal surrounding tissue was found during in vivo measurements of superficial bladder carcinoma, basal cell carcinoma of the skin, and leukoplakia with dysplasia of the lip, and in vitro investigations of resected breast cancer. (orig./MG).

  18. Phase-contrast x-ray imaging of the breast: recent developments towards clinics

    Science.gov (United States)

    Coan, P.; Bravin, A.; Tromba, G.

    2013-12-01

    Breast imaging is one of the most demanding and delicate radiological applications. Mammography is the primary diagnosis tool in breast cancer detection and national screening programmes. Recognition of breast cancer depends on the detection of subtle architectural distortion, masses showing near normal breast tissue density, skin thickening and microcalcifications. The small differences in attenuation of x-rays between normal and malignant tissue result in low contrast and make cancer detection difficult in conventional x-ray absorption mammography. Because of these challenging aspects, breast imaging has been the first and most explored diagnostic field in phase-contrast imaging research. This novel imaging method has been extensively used and has demonstrated a unique capability in producing high-contrast and sensitive images at quasi-histological resolution. The most recent and significant technical developments are introduced and results obtained by the application of various phase-contrast imaging techniques for breast imaging are reported. The first phase-contrast mammography clinical trials project is also presented and the short- and long-term future perspectives of the method are discussed.

  19. Bioluminescent imaging: a critical tool in pre-clinical oncology research.

    LENUS (Irish Health Repository)

    O'Neill, Karen

    2010-02-01

    Bioluminescent imaging (BLI) is a non-invasive imaging modality widely used in the field of pre-clinical oncology research. Imaging of small animal tumour models using BLI involves the generation of light by luciferase-expressing cells in the animal following administration of substrate. This light may be imaged using an external detector. The technique allows a variety of tumour-associated properties to be visualized dynamically in living models. The increasing use of BLI as a small-animal imaging modality has led to advances in the development of xenogeneic, orthotopic, and genetically engineered animal models expressing luciferase genes. This review aims to provide insight into the principles of BLI and its applications in cancer research. Many studies to assess tumour growth and development, as well as efficacy of candidate therapeutics, have been performed using BLI. More recently, advances have also been made using bioluminescent imaging in studies of protein-protein interactions, genetic screening, cell-cycle regulators, and spontaneous cancer development. Such novel studies highlight the versatility and potential of bioluminescent imaging in future oncological research.

  20. Magnetic resonance imaging in perinatal brain injury: clinical presentation, lesions and outcome

    Energy Technology Data Exchange (ETDEWEB)

    Rutherford, Mary; Ward, Phil; Allsop, Joanna; Counsell, Serena [Imperial College London, Hammersmith Hospital, Robert Steiner MR Unit, Imaging Sciences Department, Clinical Sciences Centre, London (United Kingdom); Srinivasan, Latha; Dyet, Leigh; Cowan, Frances [Imperial College, Hammersmith Hospital, Department of Paediatrics, Imaging Sciences Department, Clinical Sciences Centre, London (United Kingdom)

    2006-07-15

    Neonatal MR imaging is invaluable in assessing the term born neonate who presents with an encephalopathy. Successful imaging requires adaptations to both the hardware and the sequences used for adults. The perinatal and postnatal details often predict the pattern of lesions sustained and are essential for correct interpretation of the imaging findings, but additional or alternative diagnoses in infants with apparent hypoxic ischaemic encephalopathy should always be considered. Perinatally acquired lesions are usually at their most obvious between 1 and 2 weeks of age. Very early imaging (<3 days) may be useful to make management decisions in ventilated neonates, but abnormalities may be subtle at that stage. Diffusion-weighted imaging is clinically useful for the early identification of ischaemic white matter in the neonatal brain but is less reliable in detecting lesions within the basal ganglia and thalami. The pattern of lesions seen on MRI can predict neurodevelopmental outcome. Additional useful information may be obtained by advanced techniques such as MR angiography, venography and perfusion-weighted imaging. Serial imaging with quantification of both structure size and tissue damage provides invaluable insights into perinatal brain injury. (orig.)

  1. Clinical observation of metal artifacts on magnetic resonance images of oral and maxillofacial regions

    Energy Technology Data Exchange (ETDEWEB)

    Ariyoshi, Yasunori; Shimahara, Masashi; Takeishi, Hiroshi; Uesugi, Yasuo; Narabayashi, Isamu [Osaka Medical Coll., Takatsuki (Japan)

    2002-12-01

    We assessed the effect of metal materials used in prosthodontics on the clarity of clinical magnetic resonance (MR) images of the oral and maxillofacial regions in 37 patients. Excluded were patients who had undergone surgery in either region, patients with deciduous teeth, patients with a space-occupying lesion, i.e., an inflammatory change or a malignant process, and patients for whom images were affected by motion artifacts. The patients had all undergone orthopantomography, though none received dental treatment in the period between the MR imaging and orthopantomography study. T1- and T2- weighted axial images were used. There were no apparent differences between T1- and T2- weighted images in artifacts caused by metal prosthodontics, whereas artifacts caused by metal crowns were severe in comparison to those caused by metal inlays. In the lateral and apex portions of the tongue, when more than four crowns were present, artifacts had a marked influence on the image, and diagnosis could not be made. Moreover, in the upper and lower alveolus, the presence of two crowns had a similar effect, precluding diagnosis. However, in the antrum, mandibular body, and mental regions, metal artifacts had less of an effect on the images compared to that of metal artifacts in the alveolus region. (author)

  2. Clinical development of BLZ-100 for real-time optical imaging of tumors during resection

    Science.gov (United States)

    Franklin, Heather L.; Miller, Dennis M.; Hedges, Teresa; Perry, Jeff; Parrish-Novak, Julia

    2016-03-01

    Complete initial resection can give cancer patients the best opportunity for long-term survival. There is unmet need in surgical oncology for optical imaging that enables simple and precise visualization of tumors and consistent contrast with surrounding normal tissues. Near-infrared (NIR) contrast agents and camera systems that can detect them represent an area of active research and development. The investigational Tumor Paint agent BLZ-100 is a conjugate of a chlorotoxin peptide and the NIR dye indocyanine green (ICG) that has been shown to specifically bind to a broad range of solid tumors. Clinical efficacy studies with BLZ-100 are in progress, a necessary step in bringing the product into clinical practice. To ensure a product that will be useful for and accepted by surgeons, the early clinical development of BLZ- 100 incorporates multiple tumor types and imaging devices so that surgeon feedback covers the range of anticipated clinical uses. Key contrast agent characteristics include safety, specificity, flexibility in timing between dose and surgery, and breadth of tumor types recognized. Imaging devices should use wavelengths that are optimal for the contrast agent, be sensitive enough that contrast agent dosing can be adjusted for optimal contrast, include real-time video display of fluorescence and white light image, and be simple for surgeons to use with minimal disruption of surgical flow. Rapid entry into clinical studies provides the best opportunity for early surgeon feedback, enabling development of agents and devices that will gain broad acceptance and provide information that helps surgeons achieve more complete and precise resections.

  3. A compact microscope setup for multimodal nonlinear imaging in clinics and its application to disease diagnostics.

    Science.gov (United States)

    Meyer, Tobias; Baumgartl, Martin; Gottschall, Thomas; Pascher, Torbjörn; Wuttig, Andreas; Matthäus, Christian; Romeike, Bernd F M; Brehm, Bernhard R; Limpert, Jens; Tünnermann, Andreas; Guntinas-Lichius, Orlando; Dietzek, Benjamin; Schmitt, Michael; Popp, Jürgen

    2013-07-21

    The past years have seen increasing interest in nonlinear optical microscopic imaging approaches for the investigation of diseases due to the method's unique capabilities of deep tissue penetration, 3D sectioning and molecular contrast. Its application in clinical routine diagnostics, however, is hampered by large and costly equipment requiring trained staff and regular maintenance, hence it has not yet matured to a reliable tool for application in clinics. In this contribution implementing a novel compact fiber laser system into a tailored designed laser scanning microscope results in a small footprint easy to use multimodal imaging platform enabling simultaneously highly efficient generation and acquisition of second harmonic generation (SHG), two-photon excited fluorescence (TPEF) as well as coherent anti-Stokes Raman scattering (CARS) signals with optimized CARS contrast for lipid imaging for label-free investigation of tissue samples. The instrument combining a laser source and a microscope features a unique combination of the highest NIR transmission and a fourfold enlarged field of view suited for investigating large tissue specimens. Despite its small size and turnkey operation rendering daily alignment dispensable the system provides the highest flexibility, an imaging speed of 1 megapixel per second and diffraction limited spatial resolution. This is illustrated by imaging samples of squamous cell carcinoma of the head and neck (HNSCC) and an animal model of atherosclerosis allowing for a complete characterization of the tissue composition and morphology, i.e. the tissue's morphochemistry. Highly valuable information for clinical diagnostics, e.g. monitoring the disease progression at the cellular level with molecular specificity, can be retrieved. Future combination with microscopic probes for in vivo imaging or even implementation in endoscopes will allow for in vivo grading of HNSCC and characterization of plaque deposits towards the detection of high

  4. Clinical evaluation of synthetic aperture harmonic imaging for scanning focal malignant liver lesions.

    Science.gov (United States)

    Brandt, Andreas Hjelm; Hemmsen, Martin Christian; Hansen, Peter Møller; Madsen, Signe Sloth; Krohn, Paul Suno; Lange, Theis; Hansen, Kristoffer Lindskov; Jensen, Jørgen Arendt; Nielsen, Michael Bachmann

    2015-09-01

    The purpose of the study was to perform a clinical comparison of synthetic aperture sequential beamforming tissue harmonic imaging (SASB-THI) sequences with a conventional imaging technique, dynamic receive focusing with THI (DRF-THI). Both techniques used pulse inversion and were recorded interleaved using a commercial ultrasound system (UltraView 800, BK Medical, Herlev, Denmark). Thirty-one patients with malignant focal liver lesions (confirmed by biopsy or computed tomography/magnetic resonance) were scanned. Detection of malignant focal liver lesions and preference of image quality were evaluated blinded off-line by eight radiologists. In total, 2,032 evaluations of 127 image sequences were completed. The sensitivity (77% SASB-THI, 76% DRF-THI, p = 0.54) and specificity (71% SASB-THI, 72% DRF-THI, p = 0.67) of detection of liver lesions and the evaluation of image quality (p = 0.63) did not differ between SASB-THI and DRF-THI. This study indicates the ability of SASB-THI in a true clinical setting. PMID:26095533

  5. X-ray dark field imaging of human articular cartilage: Possible clinical application to orthopedic surgery

    International Nuclear Information System (INIS)

    Despite its convenience and non-invasiveness on daily clinical use, standard X-ray radiography cannot show articular cartilage. We developed a novel type of X-ray dark field imaging (DFI), which forms images only by a refracted beam with very low background illumination. We examined a disarticulated distal femur and a shoulder joint with surrounding soft tissue and skin, both excised from a human cadaver at the BL20B2 synchrotron beamline at SPring-8. The field was 90 mm wide and 90 mm high. Articular cartilage of the disarticulated distal femur was obvious on DFI, but not on standard X-ray images. Furthermore, DFI allowed visualization in situ of articular cartilage of the shoulder while covered with soft tissue and skin. The gross appearance of the articular cartilage on the dissected section of the proximal humerus was identical to the cartilage shown on the DFI image. These results suggested that DFI could provide a clinically accurate method of assessing articular cartilage. Hence, DFI would be a useful imaging tool for diagnosing joint disease such as osteoarthritis

  6. Clinical study of ex vivo photoacoustic imaging in endoscopic mucosal resection tissues

    Science.gov (United States)

    Lim, Liang; Streutker, Catherine J.; Marcon, Norman; Cirocco, Maria; Lakovlev, Vladimir V.; DaCosta, Ralph; Foster, F. S.; Wilson, Brian C.

    2015-03-01

    Accurate endoscopic detection and dysplasia in patients with Barrett's esophagus (BE) remains a major unmet clinical need. Current diagnosis use multiple biopsies under endoscopic image guidance, where up to 99% of the tissue remains unsampled, leading to significant risk of missing dysplasia. We conducted an ex vivo clinical trial using photoacoustic imaging (PAI) in patients undergoing endoscopic mucosal resection (EMR) with known high-grade dysplasia for the purpose of characterizing the esophageal microvascular pattern, with the long-term goal of performing in vivo endoscopic PAI for dysplasia detection and therapeutic guidance. EMR tissues were mounted immediately on an agar layer and covered with ultrasound gel. Digital photography guided the placement of the PAI transducer (40 MHz center frequency). The luminal side of the specimen was scanned over a field of view of 14 mm (width) by 15 mm (depth) at 680, 750, 824, 850 and 970 nm. Acoustic images were simultaneously acquired. Tissues were then sliced and fixed in formalin for histopathology with H and E staining. Analysis consisted of co-registration and correlation between the intrinsic PAI features and the histological images. The initial PAI + ultrasound images from 8 BE patients have demonstrated the technical feasibility of this approach and point to the potential of PAI to reveal the microvascular pattern within EMR specimens. There are several technical factors to be considered in rigorous interpretation of the PAI characteristics, including the loss of blood from the ex vivo specimens and the limited depth penetration of the photoacoustic signal.

  7. Congenital portosystemic shunts: Imaging findings and clinical presentations in 11 patients

    Energy Technology Data Exchange (ETDEWEB)

    Konstas, Angelos A., E-mail: akonstas@partners.org [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St, Boston, MA 02114 (United States); Digumarthy, Subba R.; Avery, Laura L. [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St, Boston, MA 02114 (United States); Wallace, Karen L. [Department of Radiology, Mount Auburn Hospital and Harvard Medical School, 330 Mount Auburn St, Cambridge, MA 02138 (United States); Lisovsky, Mikhail; Misdraji, Joseph [Department of Pathology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St, Boston, MA 02114 (United States); Hahn, Peter F. [Department of Radiology, Massachusetts General Hospital and Harvard Medical School, 55 Fruit St, Boston, MA 02114 (United States)

    2011-11-15

    Objective: To evaluate the clinical anatomy and presentations of congenital portosystemic shunts, and determine features that promote recognition on imaging. Materials and methods: Institutional review board approval was obtained for this HIPAA-compliant study. The requirement for written informed consent was waived. Radiology reports were retrospectively reviewed from non-cirrhotic patients who underwent imaging studies from January 1999 through February 2009. Clinical sources reviewed included electronic medical records, archived images and histopathological material. Results: Eleven patients with congenital portosystemic shunts were identified (six male and five female; age range 20 days to 84 years). Seven patients had extrahepatic and four patients had intrahepatic shunts. All 11 patients had absent or hypoplastic intrahepatic portal veins, a feature detected by CT and MRI, but not by US. Seven patients presented with shunt complications and four with presentations unrelated to shunt pathophysiology. Three adult patients had four splenic artery aneurysms. Prospective radiological evaluation of five adult patients with cross-sectional imaging had failed prospectively to recognize the presence of congenital portosystemic shunts on one or more imaging examinations. Conclusions: Congenital portosystemic shunts are associated with splenic artery aneurysms, a previously unrecognized association. Portosystemic shunts were undetected during prospective radiologic evaluation in the majority of adult patients, highlighting the need to alert radiologists to this congenital anomaly.

  8. Cross-sectional imaging of biliary tumors: current clinical status and future developments

    Energy Technology Data Exchange (ETDEWEB)

    Zech, Christoph J.; Schoenberg, Stefan O.; Reiser, Maximilian; Helmberger, Thomas [Institute of Clinical Radiology, Munich University Hospitals-Grosshadern, Ludwig-Maximilians-University Munich, Marchioninistrasse 15, 81377, Munich (Germany)

    2004-07-01

    Extrahepatic cholangiocarcinoma, including hilar cholangiocarcinoma, is a relatively rare diagnosis. However, it frequently has been associated with major problems in diagnostics and clinical management from its first comprehensive description by Klatskin up until today. In this article, cholangiocarcinoma, representing the most common biliary tumor, as well as the differential diagnoses of benign and malignant biliary obstruction, will be discussed. The latest improvements of cross-sectional imaging modalities (sonography, CT, MRI and PET) and their diagnostic values for detection and staging will be displayed. A practical imaging-based diagnostic approach to obstructive biliary disease will be proposed. (orig.)

  9. Image-guided radiation therapy:basic concepts and clinical potentials

    Institute of Scientific and Technical Information of China (English)

    Omar Abdel-Rahman

    2014-01-01

    The adaptation and integration of imaging into the process of cancer detection, diagnosis, and intervention is an area of medicine that is undergoing extremely rapid development. Radiation therapy is a prime example of this change. While the objectives of these developments are clear, they raise numerous issues regarding the skil s and resources that assure these technologies are appropriately integrated and applied. We wil explore the basic concepts related to image guidance in various radiotherapy-related procedures with special emphasis on the clinical potentials of this impressive technology.

  10. Upper Limb Evaluation in Duchenne Muscular Dystrophy: Fat-Water Quantification by MRI, Muscle Force and Function Define Endpoints for Clinical Trials

    Science.gov (United States)

    Ricotti, Valeria; Evans, Matthew R. B.; Sinclair, Christopher D. J.; Butler, Jordan W.; Ridout, Deborah A.; Hogrel, Jean-Yves; Emira, Ahmed; Morrow, Jasper M.; Reilly, Mary M.; Hanna, Michael G.; Janiczek, Robert L.; Matthews, Paul M.; Yousry, Tarek A.; Muntoni, Francesco; Thornton, John S.

    2016-01-01

    Objective A number of promising experimental therapies for Duchenne muscular dystrophy (DMD) are emerging. Clinical trials currently rely on invasive biopsies or motivation-dependent functional tests to assess outcome. Quantitative muscle magnetic resonance imaging (MRI) could offer a valuable alternative and permit inclusion of non-ambulant DMD subjects. The aims of our study were to explore the responsiveness of upper-limb MRI muscle-fat measurement as a non-invasive objective endpoint for clinical trials in non-ambulant DMD, and to investigate the relationship of these MRI measures to those of muscle force and function. Methods 15 non-ambulant DMD boys (mean age 13.3 y) and 10 age-gender matched healthy controls (mean age 14.6 y) were recruited. 3-Tesla MRI fat-water quantification was used to measure forearm muscle fat transformation in non-ambulant DMD boys compared with healthy controls. DMD boys were assessed at 4 time-points over 12 months, using 3-point Dixon MRI to measure muscle fat-fraction (f.f.). Images from ten forearm muscles were segmented and mean f.f. and cross-sectional area recorded. DMD subjects also underwent comprehensive upper limb function and force evaluation. Results Overall mean baseline forearm f.f. was higher in DMD than in healthy controls (pfat transformation of muscle with loss of muscle force and function. PMID:27649492

  11. Proceedings of Joint International Symposium on the role of noninvasive imaging modalities in clinical decision making of coronary artery disease

    International Nuclear Information System (INIS)

    This report contains ten papers on the use of noninvasive imaging in clinical diagnosis and decision making. Topics include a cost analysis of magnetic resonance imaging in medical technology, diagnostic uses of MRI in chronic coronary artery disease, clinical applications of cine computed tomography, the use of PET as a clinical tool, and the use of echocardiography in coronary artery disease. Individual papers are processed separately for the data base

  12. Magnetic resonance imaging and clinical findings in a miniature Schnauzer with hypodipsic hypernatremia

    International Nuclear Information System (INIS)

    A 6-month-old miniature Schnauzer presented with hypernatremia and clinical signs of vomiting, diarrhea, inappetence, and lethargy. The dog did not consume water on its own. Hypernatremia and the related clinical signs were resolved by fluid administration. Endocrinological investigations and urinalysis excluded the possibility of diabetes insipidus and hyperaldosteronism. Therefore, the dog was diagnosed with hypodipsic hypernatremia. Magnetic resonance imaging revealed dysgenesis of the corpus callosum and other forebrain structures. On the basis of these findings, congenital brain malformation associated with failure of the osmoreceptor system was suspected. (author)

  13. Clinical value of somatostatin receptor imaging in patients with suspected head and neck paragangliomas

    International Nuclear Information System (INIS)

    Paragangliomas or glomus tumours of the head and neck region are rare somatostatin receptor-expressing neuroendocrine tumours. Precise preoperative diagnosis is of special importance in order to adequately weigh the potential benefit of the operation against the inherent risks of the procedure. In this study, the clinical value of somatostatin receptor imaging was assessed in 19 patients who underwent somatostatin receptor scintigraphy because of known or suspected paraganglioma of the head and neck region. The results were compared with the results of computed tomography and/or magnetic resonance imaging, histology and clinical follow-up. [111In-DTPA-D-Phe1]-octreotide scintigraphy was performed 4-6 and 24 h after i.v. injection of 140-220 MBq 111In-octreotide. Whole-body and planar images as well as single-photon emission tomography images were acquired and lesions were graded according to qualitative tracer uptake. Somatostatin receptor imaging was positive in nine patients, identifying paragangliomas for the first time in three patients and recurrent disease in six patients. In one patient, a second, previously unknown paraganglioma site was identified. Negative results were obtained in ten patients. These patients included one suffering from chronic hyperplastic otitis externa, one with granuloma tissue and an organised haematoma, one with an acoustic neuroma, one with an asymmetric internal carotid artery, two with ectasia of the bulbus venae jugularis and one with a jugular vein thrombosis. In two patients with a strong family history of paraganglioma, individual involvement could be excluded. In only one patient did somatostatin receptor imaging and magnetic resonance imaging yield false negative results in respect of recurrent paraganglioma tissue. It is concluded that somatostatin receptor scintigraphy provides important information in patients with suspected paragangliomas of the head and neck region and has a strong impact on further therapeutic

  14. Corneal tissue water content mapping with THz imaging: preliminary clinical results (Conference Presentation)

    Science.gov (United States)

    Sung, Shijun; Bajwa, Neha; Deng, Sophie X.; Taylor, Zachary; Grundfest, Warren

    2016-03-01

    Well-regulated corneal water content is critical for ocular health and function and can be adversely affected by a number of diseases and injuries. Current clinical practice limits detection of unhealthy corneal water content levels to central corneal thickness measurements performed by ultrasound or optical coherence tomography. Trends revealing increasing or decreasing corneal thickness are fair indicators of corneal water content by individual measurements are highly inaccurate due to the poorly understood relationship between corneal thickness and natural physiologic variation. Recently the utility of THz imaging to accuarately measure corneal water content has been explored on with rabbit models. Preliminary experiments revealed that contact with dielectric windows confounded imaging data and made it nearly impossible to deconvolve thickness variations due to contact from thickness variations due to water content variation. A follow up study with a new optical design allowed the acquisition of rabbit data and the results suggest that the observed, time varying contrast was due entirely to the water dynamics of the cornea. This paper presents the first ever in vivo images of human cornea. Five volunteers with healthy cornea were recruited and their eyes were imaged three times over the course of a few minutes with our novel imaging system. Noticeable changes in corneal reflectivity were observed and attributed to the drying of the tear film. The results suggest that clinically compatible, non-contact corneal imaging is feasible and indicate that signal acquired from non-contact imaging of the cornea is a complicated coupling of stromal water content and tear film.

  15. SU-E-J-181: Magnetic Resonance Image-Guided Radiation Therapy Workflow: Initial Clinical Experience

    Energy Technology Data Exchange (ETDEWEB)

    Green, O; Kashani, R; Santanam, L; Wooten, H; Li, H; Rodriguez, V; Hu, Y; Mutic, S [Washington University School of Medicine, St. Louis, MO (United States); Hand, T; Victoria, J [ViewRay, Inc., Oakwood Village, OH (United States); Steele, C [Barnes Jewish Hospital, St Louis, MO (United States)

    2014-06-01

    Purpose: The aims of this work are to describe the workflow and initial clinical experience treating patients with an MRI-guided radiotherapy (MRIGRT) system. Methods: Patient treatments with a novel MR-IGRT system started at our institution in mid-January. The system consists of an on-board 0.35-T MRI, with IMRT-capable delivery via doubly-focused MLCs on three {sup 60} Co heads. In addition to volumetric MR-imaging, real-time planar imaging is performed during treatment. So far, eleven patients started treatment (six finished), ranging from bladder to lung SBRT. While the system is capable of online adaptive radiotherapy and gating, a conventional workflow was used to start, consisting of volumetric imaging for patient setup using visible tumor, evaluation of tumor motion outside of PTV on cine images, and real-time imaging. Workflow times were collected and evaluated to increase efficiency and evaluate feasibility of adding the adaptive and gating features while maintaining a reasonable patient throughput. Results: For the first month, physicians attended every fraction to provide guidance on identifying the tumor and an acceptable level of positioning and anatomical deviation. Average total treatment times (including setup) were reduced from 55 to 45 min after physician presence was no longer required and the therapists had learned to align patients based on soft-tissue imaging. Presently, the source strengths were at half maximum (7.7K Ci each), therefore beam-on times will be reduced after source replacement. Current patient load is 10 per day, with increase to 25 anticipated in the near future. Conclusion: On-board, real-time MRI-guided RT has been incorporated into clinical use. Treatment times were kept to reasonable lengths while including volumetric imaging, previews of tumor movement, and physician evaluation. Workflow and timing is being continuously evaluated to increase efficiency. In near future, adaptive and gating capabilities of the system will

  16. Clinical value of somatostatin receptor imaging in patients with suspected head and neck paragangliomas

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, Matthias; Dietlein, Markus; Weber, Kerstin; Moka, Detlef; Schicha, Harald [Klinik und Poliklinik fuer Nuklearmedizin, Universitaet zu Koeln, Joseph-Stelzmann-Strasse 9, 50924 Koeln (Germany); Fischer, Eva; Michel, Olaf; Stennert, Eberhard [Klinik und Poliklinik fuer Hals-, Nasen- und Ohrenheilkunde, Universitaet zu Koeln, Koeln (Germany)

    2002-12-01

    Paragangliomas or glomus tumours of the head and neck region are rare somatostatin receptor-expressing neuroendocrine tumours. Precise preoperative diagnosis is of special importance in order to adequately weigh the potential benefit of the operation against the inherent risks of the procedure. In this study, the clinical value of somatostatin receptor imaging was assessed in 19 patients who underwent somatostatin receptor scintigraphy because of known or suspected paraganglioma of the head and neck region. The results were compared with the results of computed tomography and/or magnetic resonance imaging, histology and clinical follow-up. [{sup 111}In-DTPA-D-Phe{sup 1}]-octreotide scintigraphy was performed 4-6 and 24 h after i.v. injection of 140-220 MBq {sup 111}In-octreotide. Whole-body and planar images as well as single-photon emission tomography images were acquired and lesions were graded according to qualitative tracer uptake. Somatostatin receptor imaging was positive in nine patients, identifying paragangliomas for the first time in three patients and recurrent disease in six patients. In one patient, a second, previously unknown paraganglioma site was identified. Negative results were obtained in ten patients. These patients included one suffering from chronic hyperplastic otitis externa, one with granuloma tissue and an organised haematoma, one with an acoustic neuroma, one with an asymmetric internal carotid artery, two with ectasia of the bulbus venae jugularis and one with a jugular vein thrombosis. In two patients with a strong family history of paraganglioma, individual involvement could be excluded. In only one patient did somatostatin receptor imaging and magnetic resonance imaging yield false negative results in respect of recurrent paraganglioma tissue. It is concluded that somatostatin receptor scintigraphy provides important information in patients with suspected paragangliomas of the head and neck region and has a strong impact on further

  17. The first clinical treatment with kilovoltage intrafraction monitoring (KIM): A real-time image guidance method

    Energy Technology Data Exchange (ETDEWEB)

    Keall, Paul J., E-mail: paul.keall@sydney.edu.au; O’Brien, Ricky; Huang, Chen-Yu [Radiation Physics Laboratory, Sydney Medical School, University of Sydney, Camperdown, New South Wales 2006 (Australia); Aun Ng, Jin [Radiation Physics Laboratory, Sydney Medical School, University of Sydney, Camperdown, New South Wales 2006, Australia and School of Physics, University of Sydney, Camperdown, New South Wales 2006 (Australia); Colvill, Emma [Radiation Physics Laboratory, Sydney Medical School, University of Sydney, Camperdown, New South Wales 2006, Australia and Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales 2065 (Australia); Rugaard Poulsen, Per; Fledelius, Walther [Department of Oncology, Aarhus University Hospital, 8000 Aarhus C, Denmark and Institute of Clinical Medicine, Aarhus University, 8000 Aarhus C (Denmark); Juneja, Prabhjot; Booth, Jeremy T. [School of Physics, University of Sydney, Camperdown, New South Wales 2006, Australia and Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales 2065 (Australia); Simpson, Emma; Bell, Linda; Alfieri, Florencia; Eade, Thomas; Kneebone, Andrew [Northern Sydney Cancer Centre, Royal North Shore Hospital, Sydney, New South Wales 2065 (Australia)

    2015-01-15

    Purpose: Kilovoltage intrafraction monitoring (KIM) is a real-time image guidance method that uses widely available radiotherapy technology, i.e., a gantry-mounted x-ray imager. The authors report on the geometric and dosimetric results of the first patient treatment using KIM which occurred on September 16, 2014. Methods: KIM uses current and prior 2D x-ray images to estimate the 3D target position during cancer radiotherapy treatment delivery. KIM software was written to process kilovoltage (kV) images streamed from a standard C-arm linear accelerator with a gantry-mounted kV x-ray imaging system. A 120° pretreatment kV imaging arc was acquired to build the patient-specific 2D to 3D motion correlation. The kV imager was activated during the megavoltage (MV) treatment, a dual arc VMAT prostate treatment, to estimate the 3D prostate position in real-time. All necessary ethics, legal, and regulatory requirements were met for this clinical study. The quality assurance processes were completed and peer reviewed. Results: During treatment, a prostate position offset of nearly 3 mm in the posterior direction was observed with KIM. This position offset did not trigger a gating event. After the treatment, the prostate motion was independently measured using kV/MV triangulation, resulting in a mean difference of less than 0.6 mm and standard deviation of less than 0.6 mm in each direction. The accuracy of the marker segmentation was visually assessed during and after treatment and found to be performing well. During treatment, there were no interruptions due to performance of the KIM software. Conclusions: For the first time, KIM has been used for real-time image guidance during cancer radiotherapy. The measured accuracy and precision were both submillimeter for the first treatment fraction. This clinical translational research milestone paves the way for the broad implementation of real-time image guidance to facilitate the detection and correction of geometric and

  18. Cardiac CT for the assessment of chest pain: Imaging techniques and clinical results

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Hans-Christoph, E-mail: christoph.becker@med.uni-muenchen.de [Ludwig-Maximilians-University, Grosshadern Clinic, Department of Clinical Radiology, Marchioninistr. 15, 81377 Munich (Germany); Johnson, Thorsten [Ludwig-Maximilians-University, Grosshadern Clinic, Department of Clinical Radiology, Marchioninistr. 15, 81377 Munich (Germany)

    2012-12-15

    Immediate and efficient risk stratification and management of patients with acute chest pain in the emergency department is challenging. Traditional management of these patients includes serial ECG, laboratory tests and further on radionuclide perfusion imaging or ECG treadmill testing. Due to the advances of multi-detector CT technology, dedicated coronary CT angiography provides the potential to rapidly and reliably diagnose or exclude acute coronary artery disease. Life-threatening causes of chest pain, such as aortic dissection and pulmonary embolism can simultaneously be assessed with a single scan, sometimes referred to as “triple rule out” scan. With appropriate patient selection, cardiac CT can accurately diagnose heart disease or other sources of chest pain, markedly decrease health care costs, and reliably predict clinical outcomes. This article reviews imaging techniques and clinical results for CT been used to evaluate patients with chest pain entering the emergency department.

  19. Clinical, Biological, and Imaging Features of Monogenic Alzheimer’s Disease

    Directory of Open Access Journals (Sweden)

    Andrea Pilotto

    2013-01-01

    Full Text Available The discovery of monogenic forms of Alzheimer’s Disease (AD associated with mutations within PSEN1, PSEN2, and APP genes is giving a big contribution in the understanding of the underpinning mechanisms of this complex disorder. Compared with sporadic form, the phenotype associated with monogenic cases is somewhat broader including behavioural disturbances, epilepsy, myoclonus, and focal presentations. Structural and functional imaging show typical early changes also in presymptomatic monogenic carriers. Amyloid imaging and CSF tau/Aβ ratio may be useful in the differential diagnosis with other neurodegenerative dementias, especially, in early onset cases. However, to date any specific biomarkers of different monogenic cases have been identified. Thus, in clinical practice, the early identification is often difficult, but the copresence of different elements could help in recognition. This review will focus on the clinical and instrumental markers useful for the very early identification of AD monogenic cases, pivotal in the development, and evaluation of disease-modifying therapy.

  20. In vivo inflammation mapping of periodontal disease based on diffuse reflectance spectral imaging: a clinical study

    Science.gov (United States)

    Prasanth, Chandra Sekhar; Betsy, Joseph; Jayanthi, Jayaraj L.; Nisha, Unni G.; Prasantila, Janam; Subhash, Narayanan

    2013-02-01

    Since conventional techniques using periodontal probes have inherent drawbacks in the diagnosis of different grades of gingival inflammation, development of noninvasive screening devices becomes significant. Diffuse reflectance (DR) spectra recorded with white light illumination is utilized to detect periodontal inflammation from the oxygenated hemoglobin absorption ratio R620/R575. A multispectral imaging system is utilized to record narrow-band DR images at 575 and 620 nm from the anterior sextant of the gingivia of 15 healthy volunteers and 25 patients (N=40). An experienced periodontist assesses the level of gingival inflammation at each site through periodontal probing and assigns diagnosis as healthy, mild, moderate, or severe inflammation. The DR image ratio R620/R575 computed for each pixel (8-μm resolution) from the monochrome images is pseudo-color-mapped to identify gingival inflammation sites. The DR image ratio values at each site are compared with clinical diagnosis to estimate the specificity and sensitivity of the DR imaging technique in inflammation mapping. The high diagnostic accuracy is utilized to detect underlying inflammation in six patients with a previous history of periodontitis.

  1. Clinical Utility of Positron Emission Tomography Magnetic Resonance Imaging (PET-MRI) in Gastrointestinal Cancers.

    Science.gov (United States)

    Matthews, Robert; Choi, Minsig

    2016-01-01

    Anatomic imaging utilizing both CT (computed tomography) and MRI (magnetic resonance imaging) limits the assessment of cancer metastases in lymph nodes and distant organs while functional imaging like PET (positron emission tomography) scan has its limitation in spatial resolution capacity. Hybrid imaging utilizing PET-CT and PET-MRI are novel imaging modalities that are changing the current landscape in cancer diagnosis, staging, and treatment response. MRI has shown to have higher sensitivity in soft tissue, head and neck pathology, and pelvic disease, as well as, detecting small metastases in the liver and bone compared to CT. Combining MRI with PET allows for detection of metastases that may have been missed with current imaging modalities. In this review, we will examine the clinical utility of FDG PET-MRI in the diagnosis and staging of gastrointestinal cancers with focus on esophageal, stomach, colorectal, and pancreatic cancers. We will also explore its role in treatment response and future directions associated with it. PMID:27618106

  2. Clinical value of CT three-dimensional imaging in diagnosing gastrointestinal tract diseases

    Institute of Scientific and Technical Information of China (English)

    Shao-Yin Duan; Dan-Tong Zhang; Qing-Chi Lin; Yan-Huan Wu

    2006-01-01

    AIM: To discuss the clinical value of CT three-dimensional (3-D) imaging in diagnosing gastrointestinal tract diseases.METHODS: Three-D imaging findings of 52 patients were retrospectively analyzed. Three-D imaging methods included shaded surface display (SSD), volume rendering (VR), virtual endoscopy (VE) and multiplanar reformatting (MPR). The diagnosis results of CT 3-D were evaluated by comparison with those of endoscopy and/or surgical finding.RESULTS: Fifty-two patients with gastrointestinal tract diseases were diagnosed by CT 3-D imaging, of whom 50 cases were correctly diagnosed and 2 were misdiagnosed. There were 33 cases of gastric diseases (27 with carcinoma, 5 with peptic ulcer and 1 with leiomyoma) and 19 large intestinal diseases (10 with colon carcinoma, 2 with carcinoma of the rectum, 5 with colon polypus and 2 with tuberculosis of the ileocecal junction). Twenty-two cases with prominent lesions (9 with subsequent hollow lesions), 20 with stenosis of cavity (8 with concomitant prominent lesions) and 10 with hollow lesions (5 with concomitant prominent lesions) were shown in 3-D images. The minimal lesion shown was 1.0 cm × 0.8 cm × 0.5 cm.CONCLUSION: CT 3-D imaging, a non-invasive examination without pain, can display clearly and directly the lesions of gastrointestinal tract with accurate location and high diagnosis accuracy. It is an important complementary technique to endoscopy.

  3. Clinical safety of magnetic resonance imaging in patients with implanted SynchroMed EL infusion pumps

    Energy Technology Data Exchange (ETDEWEB)

    Diehn, Felix E.; Wood, Christopher P.; Watson, Robert E.; Hunt, Christopher H. [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Mauck, William D. [Mayo Clinic, Department of Anesthesiology, Rochester, MN (United States); Burke, Michelle M. [Mayo Clinic, Department of Psychiatry and Psychology, Rochester, MN (United States)

    2011-02-15

    Patients with implanted SynchroMed spinal infusion pumps (Medtronic, Inc., Minneapolis, MN) routinely undergo magnetic resonance imaging at our institution. In August 2008, Medtronic issued an urgent medical device correction report regarding several pumps. Because of the rare potential ''for a delay in the return of proper drug infusion'' and ''for a delay in the logging of motor stall events,'' ''a patient's pump must be interrogated after MRI exposure in order to confirm proper pump functionality.'' This is particularly important in patients receiving intrathecal baclofen, for whom a delay in return of proper pump infusion could lead to life-threatening baclofen withdrawal syndrome. The objective of this report is to present our experience and protocol of performing magnetic resonance imaging in patients with implanted SynchroMed EL pumps. We retrospectively reviewed records of 86 patients with implanted SynchroMed EL spinal infusion pumps who underwent 112 examinations on 1.5-T magnetic resonance imaging scanners from September 1, 1998 to July 7, 2004. No SynchroMed EL pumps were damaged by magnetic resonance imaging, and the programmable settings remained unchanged in all patients. Our data suggest that SynchroMed EL pump malfunction is indeed rare after routine clinical 1.5-T magnetic resonance imaging examinations. However, based on the Medtronic correction report, we perform pump interrogation before and after imaging. (orig.)

  4. In vivo three-dimensional photoacoustic imaging based on a clinical matrix array ultrasound probe

    Science.gov (United States)

    Wang, Yu; Erpelding, Todd N.; Jankovic, Ladislav; Guo, Zijian; Robert, Jean-Luc; David, Guillaume; Wang, Lihong V.

    2012-06-01

    We present an integrated photoacoustic and ultrasonic three-dimensional (3-D) volumetric imaging system based on a two-dimensional (2-D) matrix array ultrasound probe. A wavelength-tunable dye laser pumped by a Q-switched Nd:YAG laser serves as the light source and a modified commercial ultrasound imaging system (iU22, Philips Healthcare) with a 2-D array transducer (X7-2, Philips Healthcare) detects both the pulse-echo ultrasound and photoacoustic signals. A multichannel data acquisition system acquires the RF channel data. The imaging system enables rendering of co-registered 3-D ultrasound and photoacoustic images without mechanical scanning. The resolution along the azimuth, elevation, and axial direction are measured to be 0.69, 0.90 and 0.84 mm for photoacoustic imaging. In vivo 3-D photoacoustic mapping of the sentinel lymph node was demonstrated in a rat model using methylene blue dye. These results highlight the clinical potential of 3-D PA imaging for identification of sentinel lymph nodes for cancer staging in humans.

  5. Laser speckle contrast imaging of cerebral blood flow in humans during neurosurgery: a pilot clinical study

    Science.gov (United States)

    Parthasarathy, Ashwin B.; Weber, Erica L.; Richards, Lisa M.; Fox, Douglas J.; Dunn, Andrew K.

    2010-11-01

    Monitoring cerebral blood flow (CBF) during neurosurgery can provide important physiological information for a variety of surgical procedures. CBF measurements are important for assessing whether blood flow has returned to presurgical baseline levels and for assessing postsurgical tissue viability. Existing techniques for intraoperative monitoring of CBF based on magnetic resonance imaging are expensive and often impractical, while techniques such as indocyanine green angiography cannot produce quantitative measures of blood flow. Laser speckle contrast imaging (LSCI) is an optical technique that has been widely used to quantitatively image relative CBF in animal models in vivo. In a pilot clinical study, we adapted an existing neurosurgical operating microscope to obtain LSCI images in humans in real time during neurosurgery under baseline conditions and after bipolar cautery. Simultaneously recorded ECG waveforms from the patient were used to develop a filter that helped reduce measurement variabilities due to motion artifacts. Results from this study demonstrate the feasibility of using LSCI to obtain blood flow images during neurosurgeries and its capability to produce full field CBF image maps with excellent spatial resolution in real-time with minimal disruption to the surgical procedure.

  6. Clinical safety of magnetic resonance imaging in patients with implanted SynchroMed EL infusion pumps

    International Nuclear Information System (INIS)

    Patients with implanted SynchroMed spinal infusion pumps (Medtronic, Inc., Minneapolis, MN) routinely undergo magnetic resonance imaging at our institution. In August 2008, Medtronic issued an urgent medical device correction report regarding several pumps. Because of the rare potential ''for a delay in the return of proper drug infusion'' and ''for a delay in the logging of motor stall events,'' ''a patient's pump must be interrogated after MRI exposure in order to confirm proper pump functionality.'' This is particularly important in patients receiving intrathecal baclofen, for whom a delay in return of proper pump infusion could lead to life-threatening baclofen withdrawal syndrome. The objective of this report is to present our experience and protocol of performing magnetic resonance imaging in patients with implanted SynchroMed EL pumps. We retrospectively reviewed records of 86 patients with implanted SynchroMed EL spinal infusion pumps who underwent 112 examinations on 1.5-T magnetic resonance imaging scanners from September 1, 1998 to July 7, 2004. No SynchroMed EL pumps were damaged by magnetic resonance imaging, and the programmable settings remained unchanged in all patients. Our data suggest that SynchroMed EL pump malfunction is indeed rare after routine clinical 1.5-T magnetic resonance imaging examinations. However, based on the Medtronic correction report, we perform pump interrogation before and after imaging. (orig.)

  7. Clinical applications of SPECT/CT: New hybrid nuclear medicine imaging system

    International Nuclear Information System (INIS)

    Interest in multimodality imaging shows no sign of subsiding. New tracers are spreading out the spectrum of clinical applications and innovative technological solutions are preparing the way for yet more modality marriages: hybrid imaging. Single photon emission computed tomography (SPECT) has enabled the evaluation of disease processes based on functional and metabolic information of organs and cells. Integration of X ray computed tomography (CT) into SPECT has recently emerged as a brilliant diagnostic tool in medical imaging, where anatomical details may delineate functional and metabolic information. SPECT/CT has proven to be valuable in oncology. For example, in the case of a patient with metastatic thyroid cancer, neither SPECT nor CT alone could identify the site of malignancy. SPECT/CT, a hybrid image, precisely identified where the surgeon should operate. However SPECT/CT is not just advantageous in oncology. It may also be used as a one-stop-shop for various diseases. Clinical applications with SPECT/CT have started and expanded in developed countries. It has been reported that moving from SPECT alone to SPECT/CT could change diagnoses in 30% of cases. Large numbers of people could therefore benefit from this shift all over the world. This report presents an overview of clinical applications of SPECT/CT and a relevant source of information for nuclear medicine physicians, radiologists and clinical practitioners. This information may also be useful for decision making when allocating resources dedicated to the health care system, a critical issue that is especially important for the development of nuclear medicine in developing countries. In this regard, the IAEA may be heavily involved in the promotion of programmes aimed at the IAEA's coordinated research projects and Technical Cooperation projects

  8. Structural and diffusion imaging versus clinical assessment to monitor amyotrophic lateral sclerosis

    Directory of Open Access Journals (Sweden)

    Arturo Cardenas-Blanco

    2016-01-01

    Full Text Available Amyotrophic lateral sclerosis is a progressive neurodegenerative disease that affects upper and lower motor neurons. Observational and intervention studies can be tracked using clinical measures such as the revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R but for a complete understanding of disease progression, objective in vivo biomarkers of both central and peripheral motor pathway pathology are highly desirable. The aim of this study was to determine the utility of structural and diffusion imaging as central nervous system biomarkers compared to the standard clinical measure, ALSFRS-R, to track longitudinal evolution using three time-point measurements. N = 34 patients with ALS were scanned and clinically assessed three times at a mean of three month time intervals. The MRI biomarkers were structural T1-weighted volumes for cortical thickness measurement as well as deep grey matter volumetry, voxel-based morphometry and diffusion tensor imaging (DTI. Cortical thickness focused specifically on the precentral gyrus while quantitative DTI biomarkers focused on the corticospinal tracts. The evolution of imaging biomarkers and ALSFRS-R scores over time were analysed using a mixed effects model that accounted for the scanning interval as a fixed effect variable, and, the initial measurements and time from onset as random variables. The mixed effects model showed a significant decrease in the ALSFRS-R score, (p  0.5. In addition, deep grey matter volumetry and voxel-based morphometry also identified no significant changes. Furthermore, the availability of three time points was able to indicate that there was a linear progression in both clinical and fractional anisotropy measures adding to the validity of these results. The results indicate that DTI is clearly a superior imaging marker compared to atrophy for tracking the evolution of the disease and can act as a central nervous biomarker in longitudinal studies. It

  9. Structural and diffusion imaging versus clinical assessment to monitor amyotrophic lateral sclerosis

    Science.gov (United States)

    Cardenas-Blanco, Arturo; Machts, Judith; Acosta-Cabronero, Julio; Kaufmann, Joern; Abdulla, Susanne; Kollewe, Katja; Petri, Susanne; Schreiber, Stefanie; Heinze, Hans-Jochen; Dengler, Reinhard; Vielhaber, Stefan; Nestor, Peter J.

    2016-01-01

    Amyotrophic lateral sclerosis is a progressive neurodegenerative disease that affects upper and lower motor neurons. Observational and intervention studies can be tracked using clinical measures such as the revised Amyotrophic Lateral Sclerosis Functional Rating Scale (ALSFRS-R) but for a complete understanding of disease progression, objective in vivo biomarkers of both central and peripheral motor pathway pathology are highly desirable. The aim of this study was to determine the utility of structural and diffusion imaging as central nervous system biomarkers compared to the standard clinical measure, ALSFRS-R, to track longitudinal evolution using three time-point measurements. N = 34 patients with ALS were scanned and clinically assessed three times at a mean of three month time intervals. The MRI biomarkers were structural T1-weighted volumes for cortical thickness measurement as well as deep grey matter volumetry, voxel-based morphometry and diffusion tensor imaging (DTI). Cortical thickness focused specifically on the precentral gyrus while quantitative DTI biomarkers focused on the corticospinal tracts. The evolution of imaging biomarkers and ALSFRS-R scores over time were analysed using a mixed effects model that accounted for the scanning interval as a fixed effect variable, and, the initial measurements and time from onset as random variables. The mixed effects model showed a significant decrease in the ALSFRS-R score, (p  0.5). In addition, deep grey matter volumetry and voxel-based morphometry also identified no significant changes. Furthermore, the availability of three time points was able to indicate that there was a linear progression in both clinical and fractional anisotropy measures adding to the validity of these results. The results indicate that DTI is clearly a superior imaging marker compared to atrophy for tracking the evolution of the disease and can act as a central nervous biomarker in longitudinal studies. It remains, however, less

  10. Clinical Outcome of Magnetic Resonance Imaging-Detected Additional Lesions in Breast Cancer Patients

    OpenAIRE

    Ha, Gi-Won; Yi, Mi Suk; Lee, Byoung Kil; Youn, Hyun Jo; Jung, Sung Hoo

    2011-01-01

    Purpose The aim of this study was to investigate the clinical outcome of additional breast lesions identified with breast magnetic resonance imaging (MRI) in breast cancer patients. Methods A total of 153 patients who underwent breast MRI between July 2006 and March 2008 were retrospectively reviewed. Thirty-three patients (21.6&) were recommended for second-look ultrasound (US) for further characterization of additional lesions detected on breast MRI and these patients constituted our study ...

  11. Clinical and image improvement of Raynaud's phenomenon after botulinum toxin type A treatment.

    Science.gov (United States)

    Zhao, HongMei; Lian, YaJun

    2015-08-01

    Raynaud's phenomenon is often accompanied by pain, digital ulceration and compromised daily activities. Pharmacological therapy or sympathectomies have been administered to diminish these symptoms but existing treatments are not invariably efficacious. A recent case series has described the use of botulinum toxin type A in the treatment of Raynaud's phenomenon. We report two patients with severe or mild Raynaud's phenomenon who were injected with BTX-A; both of whom experienced clinical and image improvement after treatment.

  12. Impact of Nonvascular Thoracic MR Imaging on the Clinical Decision Making of Thoracic Surgeons: A 2-year Prospective Study.

    Science.gov (United States)

    Ackman, Jeanne B; Gaissert, Henning A; Lanuti, Michael; Digumarthy, Subba R; Shepard, Jo-Anne O; Halpern, Elkan F; Wright, Cameron D

    2016-08-01

    Purpose To determine the impact of nonvascular thoracic magnetic resonance (MR) imaging on the clinical decision making and diagnostic certainty of thoracic surgeons. Materials and Methods Seven thoracic surgeons at Massachusetts General Hospital, an academic quaternary referral hospital, participated in this 2-year, prospective, institution review board-approved, HIPAA-compliant pre- and post-MR imaging survey study after completing a one-time demographic survey. Between July 16, 2013, and July 13, 2015, each time a thoracic surgeon ordered a nonvascular thoracic MR imaging study via radiology order entry, he or she was sent a link to the pre-test survey that ascertained the clinical rationale for MR imaging, the clinical management plan if MR imaging was not an option, and pre-test diagnostic certainty. Upon completion of the MR imaging report, the surgeon was sent a link to the post-test survey assessing if/how MR imaging changed clinical management, the surgeon's comfort with the clinical management plan, and post-test diagnostic certainty. Data were analyzed with Student t, Wilcoxon, and McNemar tests. Results A total of 99 pre- and post-test surveys were completed. Most MR imaging studies (64 of 99 [65%]) were requested because of indeterminate computed tomographic findings. The use of MR imaging significantly reduced the number of planned surgical interventions (P management plan in 95% (94 of 99) of cases. Increased diagnostic certainty as a result of MR imaging was highly significant (P < .0001). In 21% (21 of 99) of cases, definitive MR imaging results warranted no further follow-up or clinical care. Conclusion In appropriate cases, assessment with nonvascular thoracic MR imaging substantially affects the clinical decision making and diagnostic certainty of thoracic surgeons. (©) RSNA, 2016 Online supplemental material is available for this article. An earlier incorrect version of this article appeared online. This article was corrected on May 2, 2016

  13. Molecular image-directed biopsies: improving clinical biopsy selection in patients with multiple tumors

    Science.gov (United States)

    Harmon, Stephanie A.; Tuite, Michael J.; Jeraj, Robert

    2016-10-01

    Site selection for image-guided biopsies in patients with multiple lesions is typically based on clinical feasibility and physician preference. This study outlines the development of a selection algorithm that, in addition to clinical requirements, incorporates quantitative imaging data for automatic identification of candidate lesions for biopsy. The algorithm is designed to rank potential targets by maximizing a lesion-specific score, incorporating various criteria separated into two categories: (1) physician-feasibility category including physician-preferred lesion location and absolute volume scores, and (2) imaging-based category including various modality and application-specific metrics. This platform was benchmarked in two clinical scenarios, a pre-treatment setting and response-based setting using imaging from metastatic prostate cancer patients with high disease burden (multiple lesions) undergoing conventional treatment and receiving whole-body [18F]NaF PET/CT scans pre- and mid-treatment. Targeting of metastatic lesions was robust to different weighting ratios and candidacy for biopsy was physician confirmed. Lesion ranked as top targets for biopsy remained so for all patients in pre-treatment and post-treatment biopsy selection after sensitivity testing was completed for physician-biased or imaging-biased scenarios. After identifying candidates, biopsy feasibility was evaluated by a physician and confirmed for 90% (32/36) of high-ranking lesions, of which all top choices were confirmed. The remaining cases represented lesions with high anatomical difficulty for targeting, such as proximity to sciatic nerve. This newly developed selection method was successfully used to quantitatively identify candidate lesions for biopsies in patients with multiple lesions. In a prospective study, we were able to successfully plan, develop, and implement this technique for the selection of a pre-treatment biopsy location.

  14. Extending DICOM imaging to new clinical specialties in the healthcare enterprise

    Science.gov (United States)

    Kuzmak, Peter M.; Dayhoff, Ruth E.

    2002-05-01

    DICOM is a success for radiology and cardiology and it is now starting to be used for the other clinical specialties. The US Department of Veterans Affairs has been instrumental in promoting this advancement. We have worked with a number of non-radiology clinical speciality imaging vendors over the past two years, encouraging them to support DICOM, providing requirement specifications. Validating their implementations, using their products, and integrating their systems with the VA healthcare enterprise. We require each new clinical speciality vendor to support the DICOM Modality Worklist and Storage services and insist that they perform validation testing with us over the Internet. Two years ago we began working with two commercial DICOM image acquisition applications in ophthalmology and endoscopy. We are now dealing with over a dozen: five in ophthalmology, two in endoscopy, and six in dental. This has been a very productive endeavor. Because mature software development toolkits now exist, the vendors can quickly integrate DICOM with their existing imaging products. Each of the dental vendors, for example, was able to accomplish this task in less than three months. Getting the imaging modality vendors to support DICOM is only part of the story, however. We are also working on getting the VistA hospital information system to properly handle DICOM interfaces to various clinical specialties. This has been more difficult than expected because the workflow in clinical specialties is much more varied than that in radiology. This required us to develop software that is much more flexible than that used for radiology. Fortunately, the standard DICOM Modality Worklist and Storage services can be used without change. In addition to a more variable workflow, the use of structured reporting is much more advanced in clinical specialties than in radiology, and significant work is needed to define templates and communicate this data using DICOM. Since some speciality modules

  15. Current Clinical Applications and Future Potential of Diffusion Tensor Imaging in Traumatic Brain Injury.

    Science.gov (United States)

    Strauss, Sara; Hulkower, Miriam; Gulko, Edwin; Zampolin, Richard L; Gutman, David; Chitkara, Munish; Zughaft, Malka; Lipton, Michael L

    2015-12-01

    In the setting of acute central nervous system (CNS) emergencies, computed tomography (CT) and conventional magnetic resonance imaging (MRI) play an important role in the identification of life-threatening intracranial injury. However, the full extent or even presence of brain damage frequently escapes detection by conventional CT and MRI. Advanced MRI techniques such as diffusion tensor imaging (DTI) are emerging as important adjuncts in the diagnosis of microstructural white matter injury in the acute and postacute brain-injured patient. Although DTI aids in detection of brain injury pathology, which has been repeatedly associated with typical adverse clinical outcomes, the evolution of acute changes and their long-term prognostic implications are less clear and the subject of much active research. A major aim of current research is to identify imaging-based biomarkers that can identify the subset of TBI patients who are at risk for adverse outcome and can therefore most benefit from ongoing care and rehabilitation as well as future therapeutic interventions.The aim of this study is to introduce the current methods used to obtain DTI in the clinical setting, describe a set of common interpretation strategies with their associated advantages and pitfalls, as well as illustrate the clinical utility of DTI through a set of specific patient scenarios. We conclude with a discussion of future potential for the management of TBI.

  16. Is your system calibrated? MRI gradient system calibration for pre-clinical, high-resolution imaging.

    Directory of Open Access Journals (Sweden)

    James O'Callaghan

    Full Text Available High-field, pre-clinical MRI systems are widely used to characterise tissue structure and volume in small animals, using high resolution imaging. Both applications rely heavily on the consistent, accurate calibration of imaging gradients, yet such calibrations are typically only performed during maintenance sessions by equipment manufacturers, and potentially with acceptance limits that are inadequate for phenotyping. To overcome this difficulty, we present a protocol for gradient calibration quality assurance testing, based on a 3D-printed, open source, structural phantom that can be customised to the dimensions of individual scanners and RF coils. In trials on a 9.4 T system, the gradient scaling errors were reduced by an order of magnitude, and displacements of greater than 100 µm, caused by gradient non-linearity, were corrected using a post-processing technique. The step-by-step protocol can be integrated into routine pre-clinical MRI quality assurance to measure and correct for these errors. We suggest that this type of quality assurance is essential for robust pre-clinical MRI experiments that rely on accurate imaging gradients, including small animal phenotyping and diffusion MR.

  17. Naso labial cyst: presentation of a clinical case with CT and MR images

    Energy Technology Data Exchange (ETDEWEB)

    Aquilino, Raphael Navarro; Faria, Reinaldo Jose Antonio; Eid, Nayene Leocadia Manzutti; Boscolo, Frab Norberto [Universidade Estadual de Campinas (UNICAMP), Piracicaba, SP (Brazil). Faculdade de Odontologia; Bazzo, Vitor Jose [Universidade de Sao Paulo (USP), Bauru, SP (Brazil). Faculdade de Odontologia

    2008-07-01

    The naso labial cyst is