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Sample records for brainstem volumes plaques

  1. Quantitative Magnetic Resonance Imaging of Brainstem Volumes, Plaques, and Surface Area in the Occipital Regions of Patients with Multiple Sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Alper, F.; Kantarci, M.; Altunkaynak, E.; Varoglu, A. O.; Karaman, A.; Oral, E.; Okur, A. [Ataturk Univ., Erzurum (Turkey). Depts. of Radiology, Histology, Neurology and Embryology, Psychiatry

    2006-07-15

    Purpose: To determine brainstem volumes, number of plaques, and surface areas in the occipital lobes of patients with relapsing remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS), and to investigate whether there is any correlation between brainstem volume and the number/surface areas of plaque in the occipital lobes. Material and Methods: Magnetic resonance imaging was obtained on 14 relapsing-remitting (RR) and 13 secondary progressive (SP) MS patients and 26 female control subjects. The Cavalieri method was used by modern design stereology to measure brainstem volume. The point-counting grid was used to evaluate sclerotic plaque surface areas in the occipital lobe. The number of plaques in the imaging section was calculated. Results: Brainstem volumes for RR and SP with multiple sclerosis and control subjects were 3647 mm{sup 3} , 3515 mm{sup 3} , and 4517 mm{sup 3} , respectively. Mean number of plaques in the right-left occipital lobe was found to be 2.7-3.4 in RR-MS and 5.2-2.8 in SP-MS. Mean plaque surface area in the right-left occipital lobe was determined to be 58.52-88.24 mm{sup 2} in RR MS and 124.3-64.82 mm{sup 2} in SP MS. Brainstem volumes were significantly reduced in both groups of patients with MS compared to controls ( P <0.01). Conclusion: Magnetic-resonance-estimated volume and surface area values in multiple sclerosis may facilitate our understanding of the clinical situation of patients and provide a simple index for evaluating therapeutic efficiency.

  2. Quantitative Magnetic Resonance Imaging of Brainstem Volumes, Plaques, and Surface Area in the Occipital Regions of Patients with Multiple Sclerosis

    International Nuclear Information System (INIS)

    Alper, F.; Kantarci, M.; Altunkaynak, E.; Varoglu, A. O.; Karaman, A.; Oral, E.; Okur, A.

    2006-01-01

    Purpose: To determine brainstem volumes, number of plaques, and surface areas in the occipital lobes of patients with relapsing remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS), and to investigate whether there is any correlation between brainstem volume and the number/surface areas of plaque in the occipital lobes. Material and Methods: Magnetic resonance imaging was obtained on 14 relapsing-remitting (RR) and 13 secondary progressive (SP) MS patients and 26 female control subjects. The Cavalieri method was used by modern design stereology to measure brainstem volume. The point-counting grid was used to evaluate sclerotic plaque surface areas in the occipital lobe. The number of plaques in the imaging section was calculated. Results: Brainstem volumes for RR and SP with multiple sclerosis and control subjects were 3647 mm 3 , 3515 mm 3 , and 4517 mm 3 , respectively. Mean number of plaques in the right-left occipital lobe was found to be 2.7-3.4 in RR-MS and 5.2-2.8 in SP-MS. Mean plaque surface area in the right-left occipital lobe was determined to be 58.52-88.24 mm 2 in RR MS and 124.3-64.82 mm 2 in SP MS. Brainstem volumes were significantly reduced in both groups of patients with MS compared to controls ( P <0.01). Conclusion: Magnetic-resonance-estimated volume and surface area values in multiple sclerosis may facilitate our understanding of the clinical situation of patients and provide a simple index for evaluating therapeutic efficiency

  3. Abnormal trajectories in cerebellum and brainstem volumes in carriers of the fragile X premutation.

    Science.gov (United States)

    Wang, Jun Yi; Hessl, David; Hagerman, Randi J; Simon, Tony J; Tassone, Flora; Ferrer, Emilio; Rivera, Susan M

    2017-07-01

    Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder typically affecting male premutation carriers with 55-200 CGG trinucleotide repeat expansions in the FMR1 gene after age 50. The aim of this study was to examine whether cerebellar and brainstem changes emerge during development or aging in late life. We retrospectively analyzed magnetic resonance imaging scans from 322 males (age 8-81 years). Volume changes in the cerebellum and brainstem were contrasted with those in the ventricles and whole brain. Compared to the controls, premutation carriers without FXTAS showed significantly accelerated volume decrease in the cerebellum and whole brain, flatter inverted U-shaped trajectory of the brainstem, and larger ventricles. Compared to both older controls and premutation carriers without FXTAS, carriers with FXTAS exhibited significant volume decrease in the cerebellum and whole brain and accelerated volume decrease in the brainstem. We therefore conclude that cerebellar and brainstem volumes were likely affected during both development and progression of neurodegeneration in premutation carriers, suggesting that interventions may need to start early in adulthood to be most effective. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Correlation of Acute and Late Brainstem Toxicities With Dose-Volume Data for Pediatric Patients With Posterior Fossa Malignancies

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    Nanda, Ronica H., E-mail: rhazari@emory.edu [Department of Radiation Oncology, Winship Cancer Institute, Emory University College of Medicine, Atlanta, Georgia (United States); Ganju, Rohit G.; Schreibmann, Edward [Department of Radiation Oncology, Winship Cancer Institute, Emory University College of Medicine, Atlanta, Georgia (United States); Chen, Zhengjia; Zhang, Chao [Department of Biostatistics and Bioinformatics Shared Resource, Winship Cancer Institute, Emory University Rollins School of Public Health, Atlanta, Georgia (United States); Jegadeesh, Naresh; Cassidy, Richard; Deng, Claudia; Eaton, Bree R.; Esiashvili, Natia [Department of Radiation Oncology, Winship Cancer Institute, Emory University College of Medicine, Atlanta, Georgia (United States)

    2017-06-01

    Purpose: Radiation-induced brainstem toxicity after treatment of pediatric posterior fossa malignancies is incompletely understood, especially in the era of intensity modulated radiation therapy (IMRT). The rates of, and predictive factors for, brainstem toxicity after photon RT for posterior fossa tumors were examined. Methods and Materials: After institutional review board approval, 60 pediatric patients treated at our institution for nonmetastatic infratentorial ependymoma and medulloblastoma with IMRT were included in the present analysis. Dosimetric variables, including the mean and maximum dose to the brainstem, the dose to 10% to 90% of the brainstem (in 10% increments), and the volume of the brainstem receiving 40, 45, 50, and 55 Gy were recorded for each patient. Acute (onset within 3 months) and late (>3 months of RT completion) RT-induced brainstem toxicities with clinical and radiographic correlates were scored using Common Terminology Criteria for Adverse Events, version 4.0. Results: Patients aged 1.4 to 21.8 years underwent IMRT or volumetric arc therapy postoperatively to the posterior fossa or tumor bed. At a median clinical follow-up period of 2.8 years, 14 patients had developed symptomatic brainstem toxicity (crude incidence 23.3%). No correlation was found between the dosimetric variables examined and brainstem toxicity. Vascular injury or ischemia showed a strong trend toward predicting brainstem toxicity (P=.054). Patients with grade 3 to 5 brainstem toxicity had undergone treatment to significant volumes of the posterior fossa. Conclusion: The results of the present series demonstrate a low, but not negligible, risk of brainstem radiation necrosis for pediatric patients with posterior fossa malignancies treated with IMRT. No specific dose-volume correlations were identified; however, modern treatment volumes might help limit the incidence of severe toxicity. Additional work investigating inherent biologic sensitivity might also provide

  5. Association between epicardial fat volume and coronary plaques diagnosed by multislice computed tomography

    Directory of Open Access Journals (Sweden)

    José A. Morán Quijada

    2016-01-01

    Full Text Available Introduction: Coronary atherosclerotic disease is a major cause of death in Cuba and elsewhere. The volume of epicardial fat is considered a new cardiovascular risk factor because of its association with coronary atherogenesis.Objective: To determine, by multislice computed tomography, the association between epicardial fat volume and the presence of coronary atherosclerotic plaques.Method: A descriptive study was conducted with a universe of 130 patients with chest pain suggestive of ischemic heart disease, of which 117 were selected by opinion sampling. These patients underwent a calcium score study, a coronary angiography and a measurement of the epicardial fat volume.Results: Male patients predominated (54.7% and those aged 60-69 years (32.5%. A high volume of epicardial fat was found in 51.3% of patients, affecting 52.8% of women; 78.9% of patients with a calcium score between 100 and 399 UH had a high volume of epicardial fat, just as 71.2% of those with plaques and 100% of those with 4 or 5 plaques; 41% of patients had various types of plaque, which were mainly located in the anterior descending artery (88.1%.Conclusions: The measurement of the volume of epicardial fat is a useful tool to estimate the presence of coronary disease. When it was high, it was associated with older age, female gender and the presence of a higher calcium score, more plaques, more injuries and a greater involvement of the anterior descending artery.

  6. Association between increased epicardial adipose tissue volume and coronary plaque composition

    OpenAIRE

    Yamashita, Kennosuke; Yamamoto, Myong Hwa; Ebara, Seitarou; Okabe, Toshitaka; Saito, Shigeo; Hoshimoto, Koichi; Yakushiji, Tadayuki; Isomura, Naoei; Araki, Hiroshi; Obara, Chiaki; Ochiai, Masahiko

    2013-01-01

    To assess the relationship between epicardial adipose tissue volume (EATV) and plaque vulnerability in significant coronary stenosis using a 40-MHz intravascular ultrasound (IVUS) imaging system (iMap-IVUS), we analyzed 130 consecutive patients with coronary stenosis who underwent dual-source computed tomography (CT) and cardiac catheterization. Culprit lesions were imaged by iMap-IVUS before stenting. The iMAP-IVUS system classified coronary plaque components as fibrous, lipid, necrotic, or ...

  7. First experiences with model based iterative reconstructions influence on quantitative plaque volume and intensity measurements in coronary computed tomography angiography

    International Nuclear Information System (INIS)

    Precht, H.; Kitslaar, P.H.; Broersen, A.; Gerke, O.; Dijkstra, J.; Thygesen, J.; Egstrup, K.; Lambrechtsen, J.

    2017-01-01

    Purpose: Investigate the influence of adaptive statistical iterative reconstruction (ASIR) and the model-based IR (Veo) reconstruction algorithm in coronary computed tomography angiography (CCTA) images on quantitative measurements in coronary arteries for plaque volumes and intensities. Methods: Three patients had three independent dose reduced CCTA performed and reconstructed with 30% ASIR (CTDI vol at 6.7 mGy), 60% ASIR (CTDI vol 4.3 mGy) and Veo (CTDI vol at 1.9 mGy). Coronary plaque analysis was performed for each measured CCTA volumes, plaque burden and intensities. Results: Plaque volume and plaque burden show a decreasing tendency from ASIR to Veo as median volume for ASIR is 314 mm 3 and 337 mm 3 –252 mm 3 for Veo and plaque burden is 42% and 44% for ASIR to 39% for Veo. The lumen and vessel volume decrease slightly from 30% ASIR to 60% ASIR with 498 mm 3 –391 mm 3 for lumen volume and vessel volume from 939 mm 3 to 830 mm 3 . The intensities did not change overall between the different reconstructions for either lumen or plaque. Conclusion: We found a tendency of decreasing plaque volumes and plaque burden but no change in intensities with the use of low dose Veo CCTA (1.9 mGy) compared to dose reduced ASIR CCTA (6.7 mGy & 4.3 mGy), although more studies are warranted. - Highlights: • Veo decrease plaque volumes and plaque burden using low-dose CCTA. • Moving from ASIR 30%, ASIR 60% to Veo did not appear to influence the plaque intensities. • Studies including larger sample size are needed to investigate the effect on plaque.

  8. Association between increased epicardial adipose tissue volume and coronary plaque composition.

    Science.gov (United States)

    Yamashita, Kennosuke; Yamamoto, Myong Hwa; Ebara, Seitarou; Okabe, Toshitaka; Saito, Shigeo; Hoshimoto, Koichi; Yakushiji, Tadayuki; Isomura, Naoei; Araki, Hiroshi; Obara, Chiaki; Ochiai, Masahiko

    2014-09-01

    To assess the relationship between epicardial adipose tissue volume (EATV) and plaque vulnerability in significant coronary stenosis using a 40-MHz intravascular ultrasound (IVUS) imaging system (iMap-IVUS), we analyzed 130 consecutive patients with coronary stenosis who underwent dual-source computed tomography (CT) and cardiac catheterization. Culprit lesions were imaged by iMap-IVUS before stenting. The iMAP-IVUS system classified coronary plaque components as fibrous, lipid, necrotic, or calcified tissue, based on the radiofrequency spectrum. Epicardial adipose tissue was measured as the tissue ranging from -190 to -30 Hounsfield units. EATV, calculated as the sum of the fat areas on short-axis images, was 85.0 ± 34.0 cm(3). There was a positive correlation between EATV and the percentage of necrotic plaque tissue (R (2) = 0.34, P EATV and the percentage of fibrous tissue (R (2) = 0.24, P EATV (β = 0.14, P = 0.02) were independently associated with the percentage of necrotic plaque tissue. An increase in EATV was associated with the development of coronary atherosclerosis and, potentially, with the most dangerous type of plaque.

  9. Iterative model reconstruction reduces calcified plaque volume in coronary CT angiography

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    Károlyi, Mihály, E-mail: mihaly.karolyi@cirg.hu [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Szilveszter, Bálint, E-mail: szilveszter.balint@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Kolossváry, Márton, E-mail: martonandko@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Takx, Richard A.P, E-mail: richard.takx@gmail.com [Department of Radiology, University Medical Center Utrecht, 100 Heidelberglaan, 3584, CX Utrecht (Netherlands); Celeng, Csilla, E-mail: celengcsilla@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Bartykowszki, Andrea, E-mail: bartyandi@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Jermendy, Ádám L., E-mail: adam.jermendy@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Panajotu, Alexisz, E-mail: panajotualexisz@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); Karády, Júlia, E-mail: karadyjulia@gmail.com [MTA-SE Cardiovascular Imaging Research Group, Heart and Vascular Center, Semmelweis University, 68. Varosmajor st, 1122, Budapest (Hungary); and others

    2017-02-15

    Objective: To assess the impact of iterative model reconstruction (IMR) on calcified plaque quantification as compared to filtered back projection reconstruction (FBP) and hybrid iterative reconstruction (HIR) in coronary computed tomography angiography (CTA). Methods: Raw image data of 52 patients who underwent 256-slice CTA were reconstructed with IMR, HIR and FBP. We evaluated qualitative, quantitative image quality parameters and quantified calcified and partially calcified plaque volumes using automated software. Results: Overall qualitative image quality significantly improved with HIR as compared to FBP, and further improved with IMR (p < 0.01 all). Contrast-to-noise ratios were improved with IMR, compared to HIR and FBP (51.0 [43.5–59.9], 20.3 [16.2–25.9] and 14.0 [11.2–17.7], respectively, all p < 0.01) Overall plaque volumes were lowest with IMR and highest with FBP (121.7 [79.3–168.4], 138.7 [90.6–191.7], 147.0 [100.7–183.6]). Similarly, calcified volumes (>130 HU) were decreased with IMR as compared to HIR and FBP (105.9 [62.1–144.6], 110.2 [63.8–166.6], 115.9 [81.7–164.2], respectively, p < 0.05 all). High-attenuation non-calcified volumes (90–129 HU) yielded similar values with FBP and HIR (p = 0.81), however it was lower with IMR (p < 0.05 both). Intermediate- (30–89 HU) and low-attenuation (<30 HU) non-calcified volumes showed no significant difference (p = 0.22 and p = 0.67, respectively). Conclusions: IMR improves image quality of coronary CTA and decreases calcified plaque volumes.

  10. First experiences with model based iterative reconstructions influence on quantitative plaque volume and intensity measurements in coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Precht, Helle; Kitslaar, Pieter H.; Broersen, Alexander

    2017-01-01

    Purpose: Investigate the influence of adaptive statistical iterative reconstruction (ASIR) and the model- based IR (Veo) reconstruction algorithm in coronary computed tomography angiography (CCTA) im- ages on quantitative measurements in coronary arteries for plaque volumes and intensities. Methods...

  11. Inter-Scan Reproducibility of Carotid Plaque Volume Measurements by 3-D Ultrasound

    DEFF Research Database (Denmark)

    Sandholt, Benjamin V; Collet-Billon, Antoine; Entrekin, Robert

    2018-01-01

    (PPV) measure centered on MPT. Total plaque volume (TPV), PPV from a 10-mm segment and MPT were measured using dedicated semi-automated software on 38 plaques from 26 patients. Inter-scan reproducibility was assessed using the t-test, Bland-Altman plots and Pearson's correlation coefficient....... There was a mean difference of 0.01 mm in MPT (limits of agreement: -0.45 to 0.42 mm, Pearson's correlation coefficient: 0.96). Both volume measurements exhibited high reproducibility, with PPV being superior (limits of agreement: -35.3 mm3to 33.5 mm3, Pearson's correlation coefficient: 0.96) to TPV (limits...... of agreement: -88.2 to 61.5 mm3, Pearson's correlation coefficient: 0.91). The good reproducibility revealed by the present results encourages future studies on establishing plaque quantification as part of cardiovascular risk assessment and for follow-up of disease progression over time....

  12. Novel 3D-CT evaluation of carotid stent volume: greater chronological expansion of stents in patients with vulnerable plaques.

    Science.gov (United States)

    Itami, Hisakazu; Tokunaga, Koji; Okuma, Yu; Hishikawa, Tomohito; Sugiu, Kenji; Ida, Kentaro; Date, Isao

    2013-09-01

    Although self-expanding carotid stents may dilate gradually, the degrees of residual stenosis have been quantified by the NASCET criteria, which is too simple to reflect the configuration of the stented artery. We measured the volumes of the stent lumens chronologically by 3D-CT in patients after carotid artery stenting (CAS), and analyzed the correlations between the volume change and medical factors. Fourteen patients with carotid artery stenosis were treated using self-expanding, open-cell stents. All patients underwent preoperative plaque MRI (magnetization-prepared rapid acquisition gradient-echo, MPRAGE) and chronological 3D-CT examinations of their stents immediately after their placement and 1 day, 1 week, and 1 month after the procedure. The volume of the stent lumen was measured using a 3D workstation. The correlations between stent volume and various factors including the presence of underlying diseases, plaque characteristics, and the results of the CAS procedure were analyzed. Stent volume gradually increased in each case and had increased by 1.04-1.55 (mean, 1.25)-fold at 1 postoperative month. The presence of underlying medical diseases, plaque length, the degree of residual stenosis immediately after CAS, and plaque calcification did not have an impact on the change in stent volume. On the other hand, the stent volume increase was significantly larger in the patients with vulnerable plaques that demonstrated high MPRAGE signal intensity (P stent volume. Self-expanding stents in carotid arteries containing vulnerable plaques expand significantly more than those without such plaques in a follow-up period.

  13. Non-calcified coronary plaque volume inversely related to CD4 count in HIV infection

    Science.gov (United States)

    Duarte, Horacio; Matta, Jatin R.; Muldoon, Nancy; Masur, Henry; Hadigan, Colleen; Gharib, Ahmed M.

    2013-01-01

    Background Non-calcified coronary artery plaque (NCAP) may be an important predictor of cardiovascular events, however, few studies have directly measured NCAP in HIV-infected individuals. Methods We completed a prospective cross-sectional evaluation of NCAP and coronary calcium scores using CT angiography in HIV-infected subjects (n=26) without known coronary artery disease (CAD), but who had one or more CAD risk factor and compared them to controls matched on age, race, sex, body mass index and Framingham risk score (n=26). Results There was no difference in coronary calcium scores (114 ± 218 vs. 124 ± 298 p=0.89) or NCAP volume (65 ± 86 mm3 vs. 63 ± 82 mm3, p=0.38) between HIV-infected subjects and controls, respectively. Among HIV-infected subjects, lower CD4 count was associated with increased NCAP volume (r=-0.52, p=0.006). CD4 count remained a significant predictor of NCAP in a multivariate analysis that adjusted for age and duration of antiretroviral therapy. Conclusion Plaque burden is similar between HIV-infected and uninfected individuals when matched on traditional CAD risk factors, however immune function may mediate the development of atherosclerosis in HIV infection. PMID:22293714

  14. [Association of human epicardial adipose tissue volume and inflammatory mediators with atherosclerosis and vulnerable coronary atherosclerotic plaque].

    Science.gov (United States)

    Zhou, Liangliang; Gong, Jianbin; Li, Demin; Lu, Guangming; Chen, Dong; Wang, Jing

    2015-02-01

    To investigate the relation of epicardial adipose tissue volume (EATV) determined by dual-source CT (DSCT) cardiac angiography and EAT-derived inflammatory factors to coronary heart disease (CHD) and vulnerable plaque. A total of 260 patients underwent cardiac computed tomography to evaluate stenosis of coronary artery, and blood samples were obtained from each patient. CHD was confirmed in 180 patients by DSA and CHD was excluded in the remaining 80 patients (NCHD). Vascular remodeling index and plaque vulnerability parameters (fatty volume, fibrous volume and calcification volume and fiber volume) were measured in CHD patients and correlation with EATV was analyzed. Epicardial adipose tissue (EAT) and intrathoracic adipose tissue (TAT) were collected from 40 CHD patients undergoing CABG surgery, and, mRNA and protein expressions of leptin and MMP9 were detected by RT-PCR and Western blot analysis. (1) The EATV was significantly higher in the CHD group than in NCHD group ((121.2 ± 40.6) mm³ vs. (74.7 ± 18.1) mm³, P = 0.01). (2) Subgroup analysis of the CHD patients demonstrated that EATV was significantly higher in patients with positive remodeling than in patients without positive remodeling ((97.6 ± 42.0) cm³ vs. (75.5 ± 25.4) cm³, P = 0.01). Lipid plaque volume was positively correlated with EATV (r = 0.34, P = 0.002); however, fiber plaque volume was negatively correlated with EATV (r = -0.30, P = 0.008). (3) Logistic regression analysis indicated that EATV was an independent risk factor for positive vascular remodeling (OR = 2.01, 95% CI: 1.30-2.32, P = 0.01). (4) mRNA and protein expression of leptin and MMP9 in EAT was significantly upregulated in 40 CHD patients who received CABG surgery compared to 40 NCHD patients (P 0.05) in mRNA and protein expression of leptin and MMP9 from the SAT between CHD and NCHD patients. (5) In the CHD group, leptin and MMP9 levels in EAT and EATV were positively correlated with lipid plaque volume and fibrous plaque

  15. Atherosclerotic plaque volume and composition in symptomatic carotid arteries assessed with multidetector CT angiography; relationship with severity of stenosis and cardiovascular risk factors

    Energy Technology Data Exchange (ETDEWEB)

    Rozie, S.; Weert, T.T. de; Monye, C. de; Homburg, P.J.; Tanghe, H.L.J.; Lugt, A. van der [Erasmus MC, University Medical Center Rotterdam, Departments of Radiology, Rotterdam (Netherlands); Dippel, D.W.J. [Erasmus MC, University Medical Center Rotterdam, Department of Neurology, PO Box 2040, Rotterdam (Netherlands)

    2009-09-15

    The purpose of this study was to examine the volume and the composition of atherosclerotic plaque in symptomatic carotid arteries and to investigate the relationship between these plaque features and the severity of stenosis and the presence of cardiovascular risk factors. One hundred patients with cerebrovascular symptoms underwent CT angiography. We measured plaque volume (PV) and the relative contribution of plaque components (calcifications, fibrous tissue, and lipid) in the symptomatic artery. The contribution of different components was measured as the number of voxels within defined ranges of HU values (calcification >130 HU, fibrous tissue 60-130 HU, lipid core <60 HU). Fifty-seven patients had atherosclerotic plaque in the symptomatic carotid artery. The severity of stenosis and PV were moderately correlated. Age and smoking were independently related to PV. Patients with hypercholesterolemia had significantly less lipid and more calcium in their plaques than patients without hypercholesterolemia. Other cardiovascular risk factors were not significantly related to PV or plaque composition. Luminal stenosis of the carotid artery partly reflects the amount of atherosclerotic carotid disease. Plaque volume and plaque composition are associated with cardiovascular risk factors. (orig.)

  16. Atherosclerotic plaque volume and composition in symptomatic carotid arteries assessed with multidetector CT angiography; relationship with severity of stenosis and cardiovascular risk factors

    International Nuclear Information System (INIS)

    Rozie, S.; Weert, T.T. de; Monye, C. de; Homburg, P.J.; Tanghe, H.L.J.; Lugt, A. van der; Dippel, D.W.J.

    2009-01-01

    The purpose of this study was to examine the volume and the composition of atherosclerotic plaque in symptomatic carotid arteries and to investigate the relationship between these plaque features and the severity of stenosis and the presence of cardiovascular risk factors. One hundred patients with cerebrovascular symptoms underwent CT angiography. We measured plaque volume (PV) and the relative contribution of plaque components (calcifications, fibrous tissue, and lipid) in the symptomatic artery. The contribution of different components was measured as the number of voxels within defined ranges of HU values (calcification >130 HU, fibrous tissue 60-130 HU, lipid core <60 HU). Fifty-seven patients had atherosclerotic plaque in the symptomatic carotid artery. The severity of stenosis and PV were moderately correlated. Age and smoking were independently related to PV. Patients with hypercholesterolemia had significantly less lipid and more calcium in their plaques than patients without hypercholesterolemia. Other cardiovascular risk factors were not significantly related to PV or plaque composition. Luminal stenosis of the carotid artery partly reflects the amount of atherosclerotic carotid disease. Plaque volume and plaque composition are associated with cardiovascular risk factors. (orig.)

  17. Brainstem disconnection

    International Nuclear Information System (INIS)

    Duffield, Curtis; Wootton-Gorges, Sandra L.; Jocson, Jennifer

    2009-01-01

    Brainstem disconnection is a very rare neonatal abnormality, with only seven cases reported. We report a unique case of a neonate who presented at delivery with hypertonia, dysmorphic facial features, and respiratory distress, as well as numerous musculoskeletal and genitourinary abnormalities. MRI of the brain showed disconnection between the pons and medulla with cerebellar hypoplasia and absent cerebellar peduncles. It aided in the description of the neurological and vascular anomalies associated with this diagnosis. (orig.)

  18. Brainstem disconnection

    Energy Technology Data Exchange (ETDEWEB)

    Duffield, Curtis; Wootton-Gorges, Sandra L. [University of California Davis, Medical Center and UC Davis Children' s Hospital, Department of Radiology, Sacramento, CA (United States); Jocson, Jennifer [University of California Davis, Medical Center and UC Davis Children' s Hospital, Department of Pediatrics, Sacramento, CA (United States)

    2009-12-15

    Brainstem disconnection is a very rare neonatal abnormality, with only seven cases reported. We report a unique case of a neonate who presented at delivery with hypertonia, dysmorphic facial features, and respiratory distress, as well as numerous musculoskeletal and genitourinary abnormalities. MRI of the brain showed disconnection between the pons and medulla with cerebellar hypoplasia and absent cerebellar peduncles. It aided in the description of the neurological and vascular anomalies associated with this diagnosis. (orig.)

  19. Coronary Plaque Volume and Composition Assessed by Computed Tomography Angiography in Patients With Late-Onset Major Depression

    DEFF Research Database (Denmark)

    Devantier, Torben Albert; Nørgaard, Bjarne Linde; Ovrehus, Kristian Altern

    2013-01-01

    Background: Depression is a stronger predictor for the onset of or death from clinical coronary artery disease than traditional cardiovascular risk factors. The association between depression and coronary artery disease has previously been investigated in non-contrast enhanced computed tomography...... studies with conflicting results. The aim of this study was to further elucidate the depression-coronary artery disease relation by use of coronary computed tomography angiography. Methods: The calcified and noncalcified coronary plaque volumes were determined by semiautomatic volumetric quantification...... with controls (14% vs. 7%, p = 0.044). Correspondingly, having depression was associated with an increased calcified plaque proportion of 11.3 [95% confidence interval: 2.63-20.1; p = 0.012] percentage points after adjustment for demographics and cardiovascular risk factors. Conclusion: The proportion...

  20. BEDVH--A method for evaluating biologically effective dose volume histograms: Application to eye plaque brachytherapy implants

    International Nuclear Information System (INIS)

    Gagne, Nolan L.; Leonard, Kara L.; Huber, Kathryn E.; Mignano, John E.; Duker, Jay S.; Laver, Nora V.; Rivard, Mark J.

    2012-01-01

    Purpose: A method is introduced to examine the influence of implant duration T, radionuclide, and radiobiological parameters on the biologically effective dose (BED) throughout the entire volume of regions of interest for episcleral brachytherapy using available radionuclides. This method is employed to evaluate a particular eye plaque brachytherapy implant in a radiobiological context. Methods: A reference eye geometry and 16 mm COMS eye plaque loaded with 103 Pd, 125 I, or 131 Cs sources were examined with dose distributions accounting for plaque heterogeneities. For a standardized 7 day implant, doses to 90% of the tumor volume ( TUMOR D 90 ) and 10% of the organ at risk volumes ( OAR D 10 ) were calculated. The BED equation from Dale and Jones and published α/β and μ parameters were incorporated with dose volume histograms (DVHs) for various T values such as T = 7 days (i.e., TUMOR 7 BED 10 and OAR 7 BED 10 ). By calculating BED throughout the volumes, biologically effective dose volume histograms (BEDVHs) were developed for tumor and OARs. Influence of T, radionuclide choice, and radiobiological parameters on TUMOR BEDVH and OAR BEDVH were examined. The nominal dose was scaled for shorter implants to achieve biological equivalence. Results: TUMOR D 90 values were 102, 112, and 110 Gy for 103 Pd, 125 I, and 131 Cs, respectively. Corresponding TUMOR 7 BED 10 values were 124, 140, and 138 Gy, respectively. As T decreased from 7 to 0.01 days, the isobiologically effective prescription dose decreased by a factor of three. As expected, TUMOR 7 BEDVH did not significantly change as a function of radionuclide half-life but varied by 10% due to radionuclide dose distribution. Variations in reported radiobiological parameters caused TUMOR 7 BED 10 to deviate by up to 46%. Over the range of OAR α/β values, OAR 7 BED 10 varied by up to 41%, 3.1%, and 1.4% for the lens, optic nerve, and lacrimal gland, respectively. Conclusions: BEDVH permits evaluation of the

  1. Non-calcified coronary plaque volume inversely related to CD4(+) T-cell count in HIV infection.

    Science.gov (United States)

    Duarte, Horacio; Matta, Jatin R; Muldoon, Nancy; Masur, Henry; Hadigan, Colleen; Gharib, Ahmed M

    2012-01-01

    Non-calcified coronary artery plaque (NCAP) might be an important predictor of cardiovascular events; however, few studies have directly measured NCAP in HIV-infected individuals. We completed a prospective cross-sectional evaluation of NCAP and coronary calcium scores using computed tomography angiography in HIV-infected patients (n=26) without known coronary artery disease (CAD), but who had one or more CAD risk factor(s), and compared them with controls matched on age, race, sex, body mass index and Framingham Risk Score (n=26). There was no difference in coronary calcium scores (114 ± 218 versus 124 ± 298; P=0.89) or NCAP volume (65 ± 86 mm(3) versus 63 ± 82 mm(3); P=0.38) between HIV-infected patients and controls, respectively. Among HIV-infected patients, lower CD4(+) T-cell count was associated with increased NCAP volume (r=-0.52, P=0.006). The CD4(+) T-cell count remained a significant predictor of NCAP in a multivariate analysis that adjusted for age and duration of antiretroviral therapy. Plaque burden is similar between HIV-infected and uninfected individuals when matched on traditional CAD risk factors; however, immune function might mediate the development of atherosclerosis in HIV infection.

  2. [Total brain T2-hyperintense lesion-volume and the axonal damage in the normal-appearing white matter of brainstem in early lapsing-remitting multiple sclerosis].

    Science.gov (United States)

    Pascual-Lozano, A M; Martínez-Bisbal, M C; Boscá-Blasco, I; Valero-Merino, C; Coret-Ferrer, F; Martí-Bonmatí, L; Martínez-Granados, B; Celda, B; Casanova-Estruch, B

    To evaluate the relationship between the total brain T2-hyperintense lesion volume (TBT2LV) and the axonal damage in the normal-appearing white matter of brainstem measured by 1H-MRS in a group of early relapsing-remitting multiple sclerosis patients. 40 relapsing-remitting multiple sclerosis patients and ten sex- and age-matched healthy subjects were prospectively studied for two years. T2-weighted MR and 1H-MRS imaging were acquired at time of recruitment and at year two. The TBT2LV was calculated with a semiautomatic program; N-acetylaspartate (NAA), creatine (Cr) and choline (Cho) resonances areas were integrated with jMRUI program and the ratios were calculated for four volume elements that represented the brainstem. At basal study we obtained an axonal loss (as a decrement of NAA/ Cho ratio) in the group of patients compared with controls (p = 0.017); this axonal loss increased at the second year of the follow-up for patients (NAA/Cho decrease, p = 0.004, and NAA/Cr decrease, p = 0.002) meanwhile control subjects had no significant metabolic changes. Higher lesion load was correlated with a poor clinical outcome, being the correlation between the basal TBT2LV and the Expanded Disability Status Scale at second year (r = 0.299; p = 0.05). Besides, axonal loss was not homogeneous for all multiple sclerosis patients, being stronger in the subgroup of patients with high basal TBT2LV (p = 0.043; ANOVA). Our data suggest that axonal damage is early in multiple sclerosis and higher in patients high basal TBT2LV, suggesting a possible relationship between these two phenomena.

  3. Impact of motion compensation and partial volume correction for 18F-NaF PET/CT imaging of coronary plaque

    Science.gov (United States)

    Cal-González, J.; Tsoumpas, C.; Lassen, M. L.; Rasul, S.; Koller, L.; Hacker, M.; Schäfers, K.; Beyer, T.

    2018-01-01

    Recent studies have suggested that 18F-NaF-PET enables visualization and quantification of plaque micro-calcification in the coronary tree. However, PET imaging of plaque calcification in the coronary arteries is challenging because of the respiratory and cardiac motion as well as partial volume effects. The objective of this work is to implement an image reconstruction framework, which incorporates compensation for respiratory as well as cardiac motion (MoCo) and partial volume correction (PVC), for cardiac 18F-NaF PET imaging in PET/CT. We evaluated the effect of MoCo and PVC on the quantification of vulnerable plaques in the coronary arteries. Realistic simulations (Biograph TPTV, Biograph mCT) and phantom acquisitions (Biograph mCT) were used for these evaluations. Different uptake values in the calcified plaques were evaluated in the simulations, while three ‘plaque-type’ lesions of 36, 31 and 18 mm3 were included in the phantom experiments. After validation, the MoCo and PVC methods were applied in four pilot NaF-PET patient studies. In all cases, the MoCo-based image reconstruction was performed using the STIR software. The PVC was obtained from a local projection (LP) method, previously evaluated in preclinical and clinical PET. The results obtained show a significant increase of the measured lesion-to-background ratios (LBR) in the MoCo  +  PVC images. These ratios were further enhanced when using directly the tissue-activities from the LP method, making this approach more suitable for the quantitative evaluation of coronary plaques. When using the LP method on the MoCo images, LBR increased between 200% and 1119% in the simulated data, between 212% and 614% in the phantom experiments and between 46% and 373% in the plaques with positive uptake observed in the pilot patients. In conclusion, we have built and validated a STIR framework incorporating MoCo and PVC for 18F-NaF PET imaging of coronary plaques. First results indicate an improved

  4. Estimates of nuclear volume in plaque and tumor-stage mycosis fungoides. A new prognostic indicator

    DEFF Research Database (Denmark)

    Brooks, B; Sørensen, Flemming Brandt; Thestrup-Pedersen, K

    1994-01-01

    It is well documented that mycosis fungoides (MF), a cutaneous T-cell lymphoma, has a variable clinical course. Unbiased stereological estimates of three-dimensional volume-weighted mean nuclear size (nucl vV) of mycosis cells were obtained in a retrospective study of 18 patients with a total of ...

  5. Brainstem tolerance to conformal radiotherapy of skull base tumors

    International Nuclear Information System (INIS)

    Debus, J.; Hug, E.B.; Liebsch, N.J.; O'Farrel, D.; Finkelstein, D.; Efird, J.; Munzenrider, J.E.

    1997-01-01

    Purpose: The aim of this study was to analyze the long-term incidence of brainstem toxicity in patients treated for skull base tumors with high dose conformal radiotherapy. Methods and Materials: Between 1974 and 1995, 367 patients with chordomas (n = 195) and chondrosarcomas (n = 172) of the base of skull have been treated with combined megavoltage photon and 160 MeV proton radiotherapy. Following 3D treatment planning with delineation of target volumes and critical nontarget structures dose distributions and dose-volume histograms were calculated. Radiotherapy was given an 1.8 Gy or CGE (=Cobalt Gray Equivalent) dose per fraction, with prescribed target doses ranging from 63 CGE to 79.2 CGE (mean = 67.8 CGE). Doses to the brainstem surface were limited to ≤64 CGE and to the brainstem center to ≤53 CGE. Results: Follow-up time ranged from 6 months to 21.4 years (mean = 42.5 months). Brainstem toxicity was observed in 17 of 367 patients attributable to treatment, resulting in death of three patients. Actuarial rates of 5 and 10-year high-grade toxicity-free survival were 94 and 88%, respectively. Increased risk of brainstem toxicity was significantly associated with maximum dose to brainstem, volume of brainstem receiving ≥50 CGE, ≥55 CGE, and ≥60 CGE, number of surgical procedures, and prevalence of diabetes or high blood pressure. Multivariate analysis identified three independent factors as important prognosticators: number of surgical procedures (p < 0.001), volume of the brainstem receiving 60 CGE (p < 0.001), and prevalence of diabetes (p < 0.01). Conclusions: Tolerance of brainstem to fractionated radiotherapy appears to be a steep function of tissue volume included in high dose regions rather than the maximum dose of brainstem alone. In addition, presence of predisposing factors as well as extent of surgical manipulation can significantly lower brainstem tolerance in the individual patient

  6. A brainstem anosognosia of hemiparesis

    Directory of Open Access Journals (Sweden)

    Kazuo Abe

    2009-10-01

    Full Text Available A woman had anosognosia for hemiplegia as a manifestation of brainstem infarction. She had no mental or neuropsychological disturbances, and had involvement of the brainstem in the frontal/parietal-subcortical circuits to the right cerebral hemisphere. Brainstem lesions that disrupt frontal/parietal-subcortical areas may affect anosognosia for hemiplegia.

  7. Pediatric brainstem oligodendroglioma

    Directory of Open Access Journals (Sweden)

    Sandeep Mohindra

    2012-01-01

    Full Text Available The authors present the first report of pediatric brainstem oligodendroglioma, infiltrating midbrain, and medulla oblongata. The report details clinical features, radiological findings, and surgical steps. As this entity is exceedingly uncommon, the overall epidemiology, prognosis, and long-term outcome remain far from established.

  8. Vulnerable Plaque

    Science.gov (United States)

    ... plaque be prevented? Patients can lower their C-reactive protein levels in the same ways that they can cut their heart attack risk: take aspirin, eat a proper diet, quit smoking, and begin an exercise program. Researchers also think that obesity and diabetes may ...

  9. Investigation of relation between visceral and subcutaneous abdominal fat volumes and calcified aortic plaques via multislice computed tomography.

    Science.gov (United States)

    Efe, Duran; Aygün, Fatih; Acar, Türker; Yildiz, Melda; Gemici, Kazım

    2015-08-01

    The present study investigated effect of subcutaneous fat volume and abdominal visceral fat volume on aortic atherosclerosis via multislice computed tomography. The present study comprised 424 subjects who underwent non-contrast-enhanced abdominal CT in our clinic between June 2012 and June 2013. Using dedicated software visceral fat volume was calculated for each individual and then subcutaneous fat volume was calculated by subtracting visceral fat volume from total fat volume. By dividing visceral fat volume/subcutaneous fat volume participants were assigned to three groups according to their mean visceral fat volume/subcutaneous fat volume: Group 1 consisted of subjects with visceral fat volume/subcutaneous fat volume lower than 0.48 (Group 1 fat volume/subcutaneous fat volume equal to or higher than 0.48 and lower than 0.69 (0.48 ≤ Group 2 fat volume/subcutaneous fat volume equal to or higher than 0.69 (Group 3 ≥ 0.69). The mean abdominal aortic calcium scores according to Agatston scoring (au) were 136.8 ± 418.7 au in Group 1, 179.9 ± 463 au in Group 2 and 212.2 ± 486.9 in Group 3, respectively. We have demonstrated a significant correlation between visceral fat volume and abdominal aorta atherosclerosis, while there was absence of significant correlation between subcutaneous fat volume and abdominal atherosclerosis. © The Author(s) 2014.

  10. Craniofacial Pain: Brainstem Mechanisms

    Directory of Open Access Journals (Sweden)

    Barry J Sessle

    1996-01-01

    Full Text Available This article reviews recent research advances in animals that have identified critical neural elements in the brainstem receiving and transmitting craniofacial nociceptive inputs, as well as some of the mechanisms involved in the modulation and plasticity of nociceptive transmission. Nociceptive neurones in the trigeminal (V brainstem sensory nuclear complex can be classified as nociceptive-specific (NS or wide dynamic range (WDR. Some of these neurones respond exclusively to sensory inputs evoked by stimulation of facial skin or oral mucosa and have features suggesting that they are critical neural elements involved in the ability to localize an acute superficial pain and sense its intensity and duration. Many of the V brainstem nociceptive neurones, however, receive convergent inputs from afferents supplying deep craniofacial tissues (eg, dural vessel, muscle and skin or mucosa. These neurones are likely involved in deep pain, including headache, because few nociceptive neurones receive inputs exclusively from afferents supplying these tissues. These extensive convergent input patterns also appear to be important factors in pain spread and referral, and in central mechanisms underlying neuroplastic changes in V neuronal properties that may occur with injury and inflammation. For example, application of the small fibre excitant and inflammatory irritant mustard oil into the temporomandibular joint, masseter or tongue musculature induces a prolonged but reversible enhancement of responses to cutaneous and deep afferent inputs of most WDR and NS neurones. These effects may be accompanied by increased electromyographic activity reflexly induced in the masticatory muscles by mustard oil, and involve endogenous N-methyl-D-aspartate and opioid neurochemical mechanisms. Such peripherally induced modulation of brainstem nociceptive neuronal properties reflects the functional plasticity of the central V system, and may be involved in the development of

  11. Quantitative coronary plaque analysis predicts high-risk plaque morphology on coronary computed tomography angiography: results from the ROMICAT II trial.

    Science.gov (United States)

    Liu, Ting; Maurovich-Horvat, Pál; Mayrhofer, Thomas; Puchner, Stefan B; Lu, Michael T; Ghemigian, Khristine; Kitslaar, Pieter H; Broersen, Alexander; Pursnani, Amit; Hoffmann, Udo; Ferencik, Maros

    2018-02-01

    Semi-automated software can provide quantitative assessment of atherosclerotic plaques on coronary CT angiography (CTA). The relationship between established qualitative high-risk plaque features and quantitative plaque measurements has not been studied. We analyzed the association between quantitative plaque measurements and qualitative high-risk plaque features on coronary CTA. We included 260 patients with plaque who underwent coronary CTA in the Rule Out Myocardial Infarction/Ischemia Using Computer Assisted Tomography (ROMICAT) II trial. Quantitative plaque assessment and qualitative plaque characterization were performed on a per coronary segment basis. Quantitative coronary plaque measurements included plaque volume, plaque burden, remodeling index, and diameter stenosis. In qualitative analysis, high-risk plaque was present if positive remodeling, low CT attenuation plaque, napkin-ring sign or spotty calcium were detected. Univariable and multivariable logistic regression analyses were performed to assess the association between quantitative and qualitative high-risk plaque assessment. Among 888 segments with coronary plaque, high-risk plaque was present in 391 (44.0%) segments by qualitative analysis. In quantitative analysis, segments with high-risk plaque had higher total plaque volume, low CT attenuation plaque volume, plaque burden and remodeling index. Quantitatively assessed low CT attenuation plaque volume (odds ratio 1.12 per 1 mm 3 , 95% CI 1.04-1.21), positive remodeling (odds ratio 1.25 per 0.1, 95% CI 1.10-1.41) and plaque burden (odds ratio 1.53 per 0.1, 95% CI 1.08-2.16) were associated with high-risk plaque. Quantitative coronary plaque characteristics (low CT attenuation plaque volume, positive remodeling and plaque burden) measured by semi-automated software correlated with qualitative assessment of high-risk plaque features.

  12. Quantitative evaluation of high intensity signal on MIP images of carotid atherosclerotic plaques from routine TOF-MRA reveals elevated volumes of intraplaque hemorrhage and lipid rich necrotic core.

    Science.gov (United States)

    Yamada, Kiyofumi; Song, Yan; Hippe, Daniel S; Sun, Jie; Dong, Li; Xu, Dongxiang; Ferguson, Marina S; Chu, Baocheng; Hatsukami, Thomas S; Chen, Min; Zhou, Cheng; Yuan, Chun

    2012-11-29

    Carotid intraplaque hemorrhage (IPH) and lipid rich necrotic core (LRNC) have been associated with accelerated plaque growth, luminal narrowing, future surface disruption and development of symptomatic events. The aim of this study was to evaluate the quantitative relationships between high intensity signals (HIS) in the plaque on TOF-MRA and IPH or LRNC volumes as measured by multicontrast weighted CMR. Seventy six patients with a suspected carotid artery stenosis or carotid plaque by ultrasonography underwent multicontrast carotid CMR. HIS presence and volume were measured from TOF-MRA MIP images while IPH and LRNC volumes were separately measured from multicontrast CMR. For detecting IPH, HIS on MIP images overall had high specificity (100.0%, 95% CI: 93.0 - 100.0%) but relatively low sensitivity (32%, 95% CI: 20.8 - 47.9%). However, the sensitivity had a significant increasing relationship with underlying IPH volume (p = 0.033) and degree of stenosis (p = 0.022). Mean IPH volume was 2.7 times larger in those with presence of HIS than in those without (142.8 ± 97.7 mm(3) vs. 53.4 ± 56.3 mm(3), p = 0.014). Similarly, mean LRNC volume was 3.4 times larger in those with HIS present (379.8 ± 203.4 mm(3) vs. 111.3 ± 122.7 mm(3), p = 0.001). There was a strong correlation between the volume of the HIS region and the IPH volume measured from multicontrast CMR (r = 0.96, p routine, clinical TOF sequences. High intensity signals in carotid plaque on TOF-MRA MIP images are associated with increased intraplaque hemorrhage and lipid-rich necrotic core volumes. The technique is most sensitive in patients with moderate to severe stenosis.

  13. Brainstem Tuberculoma in Pregnancy

    Directory of Open Access Journals (Sweden)

    Dana A. Muin

    2015-01-01

    Full Text Available We report a case of a Somali refugee who presented in the second trimester of her first pregnancy with a four-week history of gradual right-sided sensomotoric hemisyndrome including facial palsy and left-sided paresis of the oculomotorius nerve causing drooping of the left eyelid and double vision. Cranial magnetic resonance imaging revealed a solitary brainstem lesion. Upon detection of hilar lymphadenopathy on chest X-ray (CXR, the diagnosis of disseminated tuberculosis with involvement of the central nervous system was confirmed by PCR and treatment induced with rifampicin, isoniazid, pyrazinamide, and ethambutol. The patient had a steady neurological improvement and a favorable pregnancy outcome.

  14. MR findings of brainstem injury

    Energy Technology Data Exchange (ETDEWEB)

    Park, Man Soo; Hwang, Woo Cheol; Park, Choong Ki [Hallym University College of Medicine, Seoul (Korea, Republic of); Suh, Dae Chul [University of Ulsan College of Medicine, Seoul (Korea, Republic of); Kim, Sang Joon [Dankook University of College of Medicine, Cheonan (Korea, Republic of)

    1995-02-15

    To analyze the characteristics of traumatic brainstem injury by CT and MR. CT and MR studies of 10 patients with traumatic brainstem lesion in MR were retrospectively reviewed, particularly attended to location, signal intensity and associated lesions. CT failed to depict 8 of 10 brainstem lesions. All lesions were detected in MR images with T2-weighted images showing higher detection rate (n = 10) (100%) than T1-weighted images (n = 3) (30%) or CT (n = 2) (20%). The brainstem lesions located in the dorsolateral aspects of the rostral brainstem (mid brain and upper pons) in 7 (70%) cases, in ventral aspects of rostral brain in 2 (20%) cases and in median portion of pons in 1 (10%) case. Corpus callosal (n = 5), lobar white matter (n = 5) diffuse axonal injury, and 2 hemorrhagic lesions in basal ganglia were the associated findings. MR imaging is more helpful than CT in the detection of brainstem injury, especially T2 weighted images. Primary brainstem lesions were typically located in the dorsolateral aspect of rostral brainstem (midbrain and upper pons). Corpus callosum and white matter lesions were frequently associated.

  15. Brainstem tolerance to conformal radiotherapy of skull base tumors

    International Nuclear Information System (INIS)

    Debus, J.; Hug, E.B.; Munzenrider, J.E.; Liebsch, N.J.; O'Farrell, D.; Efird, J.; Daly, W.; Suit, H.D.

    1996-01-01

    Purpose/Objective: Brainstem tolerance to inhomogenous radiation doses applied by modern conformal radiotherapy has not yet been examined. The aim of this study was to analyse the incidence of brainstem toxicity in patients treated for skull base tumors with high dose conformal radiotherapy. Materials and Methods: Between 1974 and 1995, 367 patients with chordomas (n=195) and chondrosarcomas (n=172) of the base of skull have been treated with combined megavoltage photon and 160 MeV proton radiotherapy. All patients had previously undergone biopsy, subtotal or total tumor removal. 104 patients had two or more surgical procedures before radiotherapy. Following 3D treatment planning with delineation of target volumes and critical non-target structures, dose distributions and dose volume histograms were calculated [at the time of treatment delivery]. Radiotherapy was given once a day, 1.8 Gy or CGE (Cobalt Gy Equivalent: Proton Gy X 1.1) per fraction, 5 fractions per week, with prescribed target doses ranging from 63 CGE to 79.2 CGE (mean = 67.8 CGE). Doses to the brainstem surface were limited to ≤64 CGE and to the brainstem center to ≤53 CGE. Dose distributions were developed to limit dose to brainstem surface and center; current plans limit dose to surface and center to ≤64 CGE and ≤53 CGE, respectively. Brainstem toxicity was scored according to the RTOG grading system. Results: Follow-up ranged from 6 months to 21.4 years (mean = 42.5 months). Brainstem symptoms, attributable to the treatment, developed in 17 of 282 patients with local tumor control (6.0%), resulting in death of three patients. The mean time to onset of symptoms was 17 months (range: 4.5 to 177 months). These symptoms appeared in 89.5% within 3 years. Grading of the brainstem toxicity is listed in table 1. Actuarial rates of 5 and 10 year toxicity free survival were 87% and 82% respectively. Increased risk of brainstem toxicity was significantly associated with maximum brainstem dose

  16. Mosaic Evolution of Brainstem Motor Nuclei in Catarrhine Primates

    Directory of Open Access Journals (Sweden)

    Seth D. Dobson

    2011-01-01

    Full Text Available Facial motor nucleus volume coevolves with both social group size and primary visual cortex volume in catarrhine primates as part of a specialized neuroethological system for communication using facial expressions. Here, we examine whether facial nucleus volume also coevolves with functionally unrelated brainstem motor nuclei (trigeminal motor and hypoglossal due to developmental constraints. Using phylogenetically informed multiple regression analyses of previously published brain component data, we demonstrate that facial nucleus volume is not correlated with the volume of other motor nuclei after controlling for medulla volume. Our results show that brainstem motor nuclei can evolve independently of other developmentally linked structures in association with specific behavioral ecological conditions. This finding provides additional support for the mosaic view of brain evolution.

  17. Quantitative evaluation of high intensity signal on MIP images of carotid atherosclerotic plaques from routine TOF-MRA reveals elevated volumes of intraplaque hemorrhage and lipid rich necrotic core

    Directory of Open Access Journals (Sweden)

    Yamada Kiyofumi

    2012-11-01

    Full Text Available Abstract Background Carotid intraplaque hemorrhage (IPH and lipid rich necrotic core (LRNC have been associated with accelerated plaque growth, luminal narrowing, future surface disruption and development of symptomatic events. The aim of this study was to evaluate the quantitative relationships between high intensity signals (HIS in the plaque on TOF-MRA and IPH or LRNC volumes as measured by multicontrast weighted CMR. Methods Seventy six patients with a suspected carotid artery stenosis or carotid plaque by ultrasonography underwent multicontrast carotid CMR. HIS presence and volume were measured from TOF-MRA MIP images while IPH and LRNC volumes were separately measured from multicontrast CMR. Results For detecting IPH, HIS on MIP images overall had high specificity (100.0%, 95% CI: 93.0 – 100.0% but relatively low sensitivity (32%, 95% CI: 20.8 – 47.9%. However, the sensitivity had a significant increasing relationship with underlying IPH volume (p = 0.033 and degree of stenosis (p = 0.022. Mean IPH volume was 2.7 times larger in those with presence of HIS than in those without (142.8 ± 97.7 mm3 vs. 53.4 ± 56.3 mm3, p = 0.014. Similarly, mean LRNC volume was 3.4 times larger in those with HIS present (379.8 ± 203.4 mm3 vs. 111.3 ± 122.7 mm3, p = 0.001. There was a strong correlation between the volume of the HIS region and the IPH volume measured from multicontrast CMR (r = 0.96, p  Conclusion MIP images are easily reformatted from three minute, routine, clinical TOF sequences. High intensity signals in carotid plaque on TOF-MRA MIP images are associated with increased intraplaque hemorrhage and lipid-rich necrotic core volumes. The technique is most sensitive in patients with moderate to severe stenosis.

  18. Serial changes of coronary atherosclerotic plaque: Assessment with 64-slice multi-detector computed tomography

    International Nuclear Information System (INIS)

    Kim, Eun Young; Kang, Doo Kyoung; Sun, Joo Sung; Choi, So Yeon

    2013-01-01

    Evaluate the progression of coronary atherosclerotic plaque during follow-up, and its association with cardiovascular risk factors. Fifty-six atherosclerotic patients with plaque were enrolled in this retrospective study. Patient's plaque was detected on repeat 64-slice multidetector CT scans with a mean interval of 25 ± 10 months changes in calcified and non-calcified plaque volumes and cardiovascular risk factors were assessed over time. Absolute and relative changes in plaque volume were compared, and the association between rapid progression and cardiovascular risk factors was determined. Diameter of the stenosis, length, calcified and non-calcified lesion plaque volumes increased significantly on follow-up CT. Absolute and relative annual changes in plaque volumes were significantly greater in non-calcified plaque (median, 22.7 mm 3 , 90.4%) than in calcified plaque (median, 0.7 mm 3 , 0%). Obesity, smoking, hypertension, hypercholesterolemia, and low high-density lipoprotein were significant predictors of progression of non-calcified plaque. Progression of calcified plaque was not associated with any cardiovascular risk factors. Coronary plaque volume increased significantly on follow-up CT. The rate of progression is related to non-calcified plaque than to calcified plaque. Cardiovascular risk factors are independently associated with the rapid progression of non-calcified plaque volume, but not associated with the progression of calcified plaque.

  19. Serial changes of coronary atherosclerotic plaque: Assessment with 64-slice multi-detector computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Young; Kang, Doo Kyoung; Sun, Joo Sung; Choi, So Yeon [Ajou University School of Medicine, Suwon (Korea, Republic of)

    2013-12-15

    Evaluate the progression of coronary atherosclerotic plaque during follow-up, and its association with cardiovascular risk factors. Fifty-six atherosclerotic patients with plaque were enrolled in this retrospective study. Patient's plaque was detected on repeat 64-slice multidetector CT scans with a mean interval of 25 ± 10 months changes in calcified and non-calcified plaque volumes and cardiovascular risk factors were assessed over time. Absolute and relative changes in plaque volume were compared, and the association between rapid progression and cardiovascular risk factors was determined. Diameter of the stenosis, length, calcified and non-calcified lesion plaque volumes increased significantly on follow-up CT. Absolute and relative annual changes in plaque volumes were significantly greater in non-calcified plaque (median, 22.7 mm{sup 3}, 90.4%) than in calcified plaque (median, 0.7 mm{sup 3}, 0%). Obesity, smoking, hypertension, hypercholesterolemia, and low high-density lipoprotein were significant predictors of progression of non-calcified plaque. Progression of calcified plaque was not associated with any cardiovascular risk factors. Coronary plaque volume increased significantly on follow-up CT. The rate of progression is related to non-calcified plaque than to calcified plaque. Cardiovascular risk factors are independently associated with the rapid progression of non-calcified plaque volume, but not associated with the progression of calcified plaque.

  20. Plaquing procedure for infectious hematopoietic necrosis virus

    Science.gov (United States)

    Burke, J.A.; Mulcahy, D.

    1980-01-01

    A single overlay plaque assay was designed and evaluated for infectious hematopoietic necrosis virus. Epithelioma papillosum carpio cells were grown in normal atmosphere with tris(hydroxymethyl)aminomethane- or HEPES (N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid)-buffered media. Plaques were larger and formed more quickly on 1- to 3-day-old cell monolayers than on older monolayers. Cell culture medium with a 10% addition of fetal calf serum (MEM 10) or without serum (MEM 0) were the most efficient virus diluents. Dilution with phosphate-buffered saline, saline, normal broth, or deionized water reduced plaque numbers. Variations in the pH (7.0 to 8.0) of a MEM 0 diluent did not affect plaque numbers. Increasing the volume of viral inoculum above 0.15 ml (15- by 60-mm plate) decreased plaquing efficiency. Significantly more plaques occurred under gum tragacanth and methylcellulose than under agar or agarose overlays. Varying the pH (6.8 to 7.4) of methylcellulose overlays did not significantly change plaque numbers. More plaques formed under the thicker overlays of both methylcellulose and gum tragacanth. Tris(hydroxymethyl)aminomethane and HEPES performed equally well, buffering either medium or overlay. Plaque numbers were reduced when cells were rinsed after virus adsorption or less than 1 h was allowed for adsorption. Variation in adsorption time between 60 and 180 min did not change plaque numbers. The mean plaque formation time was 7 days at 16 degrees C. The viral dose response was linear when the standardized assay was used.

  1. [Brachytherapy of brainstem tumors].

    Science.gov (United States)

    Julow, Jenö; Viola, Arpád; Major, Tibor; Valálik, István; Sági, Sarolta; Mangel, László; Kovács, Rita Beáta; Repa, Imre; Bajzik, Gábor; Németh, György

    2004-01-20

    The optimal therapy of brain stem tumours of different histopathology determines the expected length of survival. Authors report 125Iodine interstitial irradiation of brain stem tumours with stereotactic brachytherapy. Two patients having brain stem tumours were suffering from glioma or from metastases of a carcinoma. In Case 1 the tumour volume was 1.98 cm3 at the time of planning interstitial irradiation. The control MRI examination performed at 42 months post-op showed a postirradiation cyst size of 5.73 cm3 indicating 65.5% shrinkage. In Case 2 the shrinkage was more apparent as the tumour volume measured on the control MRI at 8 months post-op was only 0.16 cm3 indicating 97.4% shrinkage of the 6.05 cm3 target volume at the time of brachytherapy with the metastasis practically disappearing. Quick access to histopathological results of the stereotactic intraoperative biopsy made it possible to carry out the 125Iodine stereotactic brachytherapy immediately after the biopsy, resulting in less inconvenience for patients of a second possible intervention. The control MRI scans show significant shrinkage of tumours in both patients. The procedure can be performed as a biopsy. The CT and image fusion guided 125Iodine stereotactic brachytherapy can be well planned dosimetrically and is surgically precise.

  2. Systematic Morphometry of Catecholamine Nuclei in the Brainstem.

    Science.gov (United States)

    Bucci, Domenico; Busceti, Carla L; Calierno, Maria T; Di Pietro, Paola; Madonna, Michele; Biagioni, Francesca; Ryskalin, Larisa; Limanaqi, Fiona; Nicoletti, Ferdinando; Fornai, Francesco

    2017-01-01

    Catecholamine nuclei within the brainstem reticular formation (RF) play a pivotal role in a variety of brain functions. However, a systematic characterization of these nuclei in the very same experimental conditions is missing so far. Tyrosine hydroxylase (TH) immune-positive cells of the brainstem correspond to dopamine (DA)-, norepinephrine (NE)-, and epinephrine (E)-containing cells. Here, we report a systematic count of TH-positive neurons in the RF of the mouse brainstem by using stereological morphometry. All these nuclei were analyzed for anatomical localization, rostro-caudal extension, volume, neuron number, neuron density, and mean neuronal area for each nucleus. The present data apart from inherent informative value wish to represent a reference for neuronal mapping in those studies investigating the functional anatomy of the brainstem RF. These include: the sleep-wake cycle, movement control, muscle tone modulation, mood control, novelty orienting stimuli, attention, archaic responses to internal and external stressful stimuli, anxiety, breathing, blood pressure, and innumerable activities modulated by the archaic iso-dendritic hard core of the brainstem RF. Most TH-immune-positive cells fill the lateral part of the RF, which indeed possesses a high catecholamine content. A few nuclei are medial, although conventional nosography considers all these nuclei as part of the lateral column of the RF. Despite the key role of these nuclei in psychiatric and neurological disorders, only a few of them aspired a great attention in biomedical investigation, while most of them remain largely obscure although intense research is currently in progress. A simultaneous description of all these nuclei is not simply key to comprehend the variety of brainstem catecholamine reticular neurons, but probably represents an intrinsically key base for understanding brain physiology and physiopathology.

  3. Systematic Morphometry of Catecholamine Nuclei in the Brainstem

    Directory of Open Access Journals (Sweden)

    Domenico Bucci

    2017-11-01

    Full Text Available Catecholamine nuclei within the brainstem reticular formation (RF play a pivotal role in a variety of brain functions. However, a systematic characterization of these nuclei in the very same experimental conditions is missing so far. Tyrosine hydroxylase (TH immune-positive cells of the brainstem correspond to dopamine (DA-, norepinephrine (NE-, and epinephrine (E-containing cells. Here, we report a systematic count of TH-positive neurons in the RF of the mouse brainstem by using stereological morphometry. All these nuclei were analyzed for anatomical localization, rostro-caudal extension, volume, neuron number, neuron density, and mean neuronal area for each nucleus. The present data apart from inherent informative value wish to represent a reference for neuronal mapping in those studies investigating the functional anatomy of the brainstem RF. These include: the sleep-wake cycle, movement control, muscle tone modulation, mood control, novelty orienting stimuli, attention, archaic responses to internal and external stressful stimuli, anxiety, breathing, blood pressure, and innumerable activities modulated by the archaic iso-dendritic hard core of the brainstem RF. Most TH-immune-positive cells fill the lateral part of the RF, which indeed possesses a high catecholamine content. A few nuclei are medial, although conventional nosography considers all these nuclei as part of the lateral column of the RF. Despite the key role of these nuclei in psychiatric and neurological disorders, only a few of them aspired a great attention in biomedical investigation, while most of them remain largely obscure although intense research is currently in progress. A simultaneous description of all these nuclei is not simply key to comprehend the variety of brainstem catecholamine reticular neurons, but probably represents an intrinsically key base for understanding brain physiology and physiopathology.

  4. Brainstem evoked potentials in infantile spasms

    International Nuclear Information System (INIS)

    Miyazaki, Masahito; Hashimoto, Toshiaki; Murakawa, Kazuyoshi; Tayama, Masanobu; Kuroda, Yasuhiro

    1992-01-01

    In ten patients with infantile spasms, brainstem evoked potentials and MRI examinations were performed to evaluate the brainstem involvement. The result of short latency somatosensory evoked potentials (SSEP) following the right median nerve stimulation revealed abnormal findings including the absence or low amplitudes of the waves below wave P3 and delayed central conduction time in 7 of the ten patients. The result of auditory brainstem responses (ABR) revealed abnormal findings including low amplitudes of wave V, prolonged interpeak latency of waves I-V and absence of the waves below wave IV in 5 of the ten patients. The result of the MRI examinations revealed various degrees of the brainstem atrophy in 6 of the ten patients, all of whom showed abnormal brainstem evoked potentials. The result of this study demonstrates that patients with infantile spasms are frequently associated with brainstem dysfunction and raises the possibility that brainstem atrophy might be a cause of infantile spasms. (author)

  5. Lyme disease of the brainstem

    Energy Technology Data Exchange (ETDEWEB)

    Kalina, Peter [Mayo Clinic, Department of Radiology, Rochester, MN (United States); Decker, Andrew [Northern Westchester Hospital Center, Department of Neurology, Mt. Kisco, NY (United States); Kornel, Ezriel [Northern Westchester Hospital Center, Division of Neurosurgery, Mt. Kisco, NY (United States); Halperin, John J. [North Shore University Hospital, Department of Neurology, Manhasset, NY (United States)

    2005-12-01

    Lyme disease is a multisystem infectious disease caused by the tick-borne spirochete, Borrelia burgdorferi. Central nervous system (CNS) involvement typically causes local inflammation, most commonly meningitis, but rarely parenchymal brain involvement. We describe a patient who presented with clinical findings suggesting a brainstem process. Magnetic resonance imaging (MRI) and positron emission tomography (PET) suggested a brainstem neoplasm. Prior to biopsy, laboratory evaluation led to the diagnosis of Lyme disease. Clinical and imaging abnormalities improved markedly following antimicrobial therapy. We describe Lyme disease involvement of the cerebellar peduncles with hypermetabolism on PET. Although MRI is the primary imaging modality for most suspected CNS pathology, the practical applications of PET continue to expand. (orig.)

  6. Lyme disease of the brainstem

    International Nuclear Information System (INIS)

    Kalina, Peter; Decker, Andrew; Kornel, Ezriel; Halperin, John J.

    2005-01-01

    Lyme disease is a multisystem infectious disease caused by the tick-borne spirochete, Borrelia burgdorferi. Central nervous system (CNS) involvement typically causes local inflammation, most commonly meningitis, but rarely parenchymal brain involvement. We describe a patient who presented with clinical findings suggesting a brainstem process. Magnetic resonance imaging (MRI) and positron emission tomography (PET) suggested a brainstem neoplasm. Prior to biopsy, laboratory evaluation led to the diagnosis of Lyme disease. Clinical and imaging abnormalities improved markedly following antimicrobial therapy. We describe Lyme disease involvement of the cerebellar peduncles with hypermetabolism on PET. Although MRI is the primary imaging modality for most suspected CNS pathology, the practical applications of PET continue to expand. (orig.)

  7. Variables affecting viral plaque formation in microculture plaque assays using homologous antibody in a liquid overlay.

    Science.gov (United States)

    Randhawa, A S; Stanton, G J; Green, J A; Baron, S

    1977-05-01

    A liquid antibody microculture plaque assay and the variables that govern its effectiveness are described. The assay is based on the principle that low concentrations of homologous antibody can inhibit secondary plaque formation without inhibiting formation of primary plaques. Thus, clear plaques that followed a linear dose response were produced. The assay was found to be more rapid, less cumbersome, and less expensive than assays using agar overlays and larger tissue culture plates. It was reproducible, quantitative, and had about the same sensitivity as the agar overlay technique in measuring infectious coxsackievirus type B-3. It was more sensitive in assaying adenovirus type 3 and Western equine encephalomyelitis, vesicular stomatitis, Semliki forest, Sendai, Sindbis, and Newcastle disease viruses than were liquid, carboxymethylcellulose, and methylcellulose microculture plaque assays. The variables influencing sensitivity and accuracy, as determined by using coxsackievirus type B-3, were: (i) the inoculum volume of virus; (ii) the incubation period of virus; and (iii) the incubation temperature.

  8. The relationship of age, gender, and IQ with the brainstem and thalamus in healthy children and adolescents: a magnetic resonance imaging volumetric study.

    Science.gov (United States)

    Xie, Yuhuan; Chen, Yian Ann; De Bellis, Michael D

    2012-03-01

    In healthy children, there is a paucity of information on the growth of the brainstem and thalamus measured anatomically magnetic resonance imaging. The relations of age, gender, and age by gender with brainstem and thalamus volumes were analyzed from magnetic resonance brain images of 122 healthy children and adolescents (62 males, 60 females; ages 4 to 17). Results showed that age is a significant predictor of brainstem and thalamus volumes. The volume of the brainstem increases with age, while thalamus volume declines with age. The volume of the right thalamus is significantly larger than that of the left in both genders, with greater rightward asymmetry and greater thalamus to grey matter ratio in females. Males have larger brainstems, but these differences are not significant when covarying for cerebral volume. Larger thalami were associated with higher Verbal IQ. These normative pediatric data are of value to researchers who study these regions in neurodevelopmental disorders.

  9. A comparison between plaque-based and vessel-based measurement for plaque component using volumetric intravascular ultrasound radiofrequency data analysis.

    Science.gov (United States)

    Shin, Eun-Seok; Garcia-Garcia, Hector M; Garg, Scot; Serruys, Patrick W

    2011-04-01

    Although percent plaque components on plaque-based measurement have been used traditionally in previous studies, the impact of vessel-based measurement for percent plaque components have yet to be studied. The purpose of this study was therefore to correlate percent plaque components derived by plaque- and vessel-based measurement using intravascular ultrasound virtual histology (IVUS-VH). The patient cohort comprised of 206 patients with de novo coronary artery lesions who were imaged with IVUS-VH. Age ranged from 35 to 88 years old, and 124 patients were male. Whole pullback analysis was used to calculate plaque volume, vessel volume, and absolute and percent volumes of fibrous, fibrofatty, necrotic core, and dense calcium. The plaque and vessel volumes were well correlated (r = 0.893, P measurement was also highly correlated with vessel-based measurement. Therefore, the percent plaque component volume calculated by vessel volume could be used instead of the conventional percent plaque component volume calculated by plaque volume.

  10. Influence of Adaptive Statistical Iterative Reconstruction on coronary plaque analysis in coronary computed tomography angiography

    DEFF Research Database (Denmark)

    Precht, Helle; Kitslaar, Pieter H; Broersen, Alexander

    2016-01-01

    performed. Images were reconstructed using FBP, 30% and 60% adaptive statistical IR (ASIR). Coronary plaque analysis was performed as per patient and per vessel (LM, LAD, CX and RCA) measurements. Lumen and vessel volumes and plaque burden measurements were based on automatic detected contours in each...... reconstruction. Lumen and plaque intensity measurements and HU based plaque characterization were based on corrected contours copied to each reconstruction. RESULTS: No significant changes between FBP and 30% ASIR were found except for lumen- (-2.53 HU) and plaque intensities (-1.28 HU). Between FBP and 60% ASIR...... the change in total volume showed an increase of 0.94%, 4.36% and 2.01% for lumen, plaque and vessel, respectively. The change in total plaque burden between FBP and 60% ASIR was 0.76%. Lumen and plaque intensities decreased between FBP and 60% ASIR with -9.90 HU and -1.97 HU, respectively. The total plaque...

  11. Brainstem pathology in spasmodic dysphonia

    Science.gov (United States)

    Simonyan, Kristina; Ludlow, Christy L.; Vortmeyer, Alexander O.

    2009-01-01

    Spasmodic dysphonia (SD) is a primary focal dystonia of unknown pathophysiology, characterized by involuntary spasms in the laryngeal muscles during speech production. We examined two rare cases of postmortem brainstem tissue from SD patients compared to four controls. In SD patients, small clusters of inflammation were found in the reticular formation surrounding solitary tract, spinal trigeminal and ambigual nuclei, inferior olive and pyramids. Mild neuronal degeneration and depigmentation were observed in the substantia nigra and locus coeruleus. No abnormal protein accumulations and no demyelination or axonal degeneration were found. These neuropathological findings may provide insights into the pathophysiology of SD. PMID:19795469

  12. Surgical management of spontaneous hypertensive brainstem hemorrhage

    Directory of Open Access Journals (Sweden)

    Bal Krishna Shrestha

    2015-09-01

    Full Text Available Spontaneous hypertensive brainstem hemorrhage is the spontaneous brainstem hemorrhage associated with long term hypertension but not having definite focal or objective lesion. It is a catastrophic event which has a poor prognosis and usually managed conservatively. It is not uncommon, especially in eastern Asian populations, accounting approximately for 10% of the intracerebral hemorrhage. Before the advent of computed tomography, the diagnosis of brainstem hemorrhage was usually based on the clinical picture or by autopsy and believed to be untreatable via surgery. The introduction of computed tomography permitted to categorize the subtypes of brainstem hemorrhage with more predicted outcome. Continuous ongoing developments in the stereotactic surgery and microsurgery have added more specific surgical management in these patients. However, whether to manage conservatively or promptly with surgical evacuation of hematoma is still a controversy. Studies have shown that an accurate prognostic assessment based on clinical and radiological features on admission is critical for establishing a reasonable therapeutic approach. Some authors have advocate conservative management, whereas others have suggested the efficacy of surgical treatment in brainstem hemorrhage. With the widening knowledge in microsurgical techniques as well as neuroimaging technology, there seems to have more optimistic hope of surgical management of spontaneous hypertensive brainstem hemorrhage for better prognosis. Here we present five cases of severe spontaneous hypertensive brainstem hemorrhage patients who had undergone surgery; and explore the possibilities of surgical management in patients with the spontaneous hypertensive brainstem hemorrhage.

  13. Imaging unstable plaque

    International Nuclear Information System (INIS)

    SRIRANJAN, Rouchelle S.; TARKIN, Jason M.; RUDD, James H.; EVANS, Nicholas R.; CHOWDHURY, Mohammed M.

    2016-01-01

    Recent advances in imaging technology have enabled us to utilise a range of diagnostic approaches to better characterise high-risk atherosclerotic plaque. The aim of this article is to review current and emerging techniques used to detect and quantify unstable plaque in the context of large and small arterial systems and will focus on both invasive and non-invasive imaging techniques. While the diagnosis of clinically relevant atherosclerosis still relies heavily on anatomical assessment of arterial luminal stenosis, evolving multimodal cross-sectional imaging techniques that encompass novel molecular probes can provide added information with regard to plaque composition and overall disease burden. Novel molecular probes currently being developed to track precursors of plaque rupture such as inflammation, micro-calcification, hypoxia and neoangiogenesis are likely to have translational applications beyond diagnostics and have the potential to play a part in quantifying early responses to therapeutic interventions and more accurate cardiovascular risk stratification.

  14. Low copper and high manganese levels in prion protein plaques

    Science.gov (United States)

    Johnson, Christopher J.; Gilbert, P.U.P.A.; Abrecth, Mike; Baldwin, Katherine L.; Russell, Robin E.; Pedersen, Joel A.; McKenzie, Debbie

    2013-01-01

    Accumulation of aggregates rich in an abnormally folded form of the prion protein characterize the neurodegeneration caused by transmissible spongiform encephalopathies (TSEs). The molecular triggers of plaque formation and neurodegeneration remain unknown, but analyses of TSE-infected brain homogenates and preparations enriched for abnormal prion protein suggest that reduced levels of copper and increased levels of manganese are associated with disease. The objectives of this study were to: (1) assess copper and manganese levels in healthy and TSE-infected Syrian hamster brain homogenates; (2) determine if the distribution of these metals can be mapped in TSE-infected brain tissue using X-ray photoelectron emission microscopy (X-PEEM) with synchrotron radiation; and (3) use X-PEEM to assess the relative amounts of copper and manganese in prion plaques in situ. In agreement with studies of other TSEs and species, we found reduced brain levels of copper and increased levels of manganese associated with disease in our hamster model. We also found that the in situ levels of these metals in brainstem were sufficient to image by X-PEEM. Using immunolabeled prion plaques in directly adjacent tissue sections to identify regions to image by X-PEEM, we found a statistically significant relationship of copper-manganese dysregulation in prion plaques: copper was depleted whereas manganese was enriched. These data provide evidence for prion plaques altering local transition metal distribution in the TSE-infected central nervous system.

  15. Short-term consumption of probiotic lactobacilli has no effect on acid production of supragingival plaque

    DEFF Research Database (Denmark)

    Marttinen, Aino; Haukioja, Anna; Karjalainen, Sára

    2011-01-01

    . reuteri SD2112 and PTA 5289 for 2 weeks. At baseline and at the end of each tablet period, all available supragingival plaque was collected. Lactic acid production was determined from a fixed volume (8 µl) of fresh plaque and the rest of the plaque was used for culturing MS and lactobacilli. The retention...

  16. Imaging of adult brainstem gliomas

    Energy Technology Data Exchange (ETDEWEB)

    Purohit, Bela, E-mail: purohitbela@yahoo.co.in; Kamli, Ali A.; Kollias, Spyros S.

    2015-04-15

    Highlights: •BSG are classified on MRI into diffuse low-grade, malignant, focal tectal and exophytic subtypes. •Their prognosis and treatment is variable and is almost similar to adult supratentorial gliomas. •This article illustrates the imaging of adult BSGs on MRI and FET-PET. •We also describe prognostic factors and the treatment options of these tumours. -- Abstract: Brainstem gliomas (BSGs) are uncommon in adults accounting for about 2% of all intracranial neoplasms. They are often phenotypically low-grade as compared to their more common paediatric counterparts. Since brainstem biopsies are rarely performed, these tumours are commonly classified according to their MR imaging characteristics into 4 subgroups: (a) diffuse intrinsic low-grade gliomas, (b) enhancing malignant gliomas, (c) focal tectal gliomas and (d) exophytic gliomas/other subtypes. The prognosis and treatment is variable for the different types and is almost similar to adult supratentorial gliomas. Radiotherapy (RT) with adjuvant chemotherapy is the standard treatment of diffuse low-grade and malignant BSGs, whereas, surgical resection is limited to the exophytic subtypes. Review of previous literature shows that the detailed imaging of adult BSGs has not received significant attention. This review illustrates in detail the imaging features of adult BSGs using conventional and advanced MR techniques like diffusion weighted imaging (DWI), diffusion tensor imaging (DTI), MR perfusion weighted imaging (PWI), MR spectroscopy (MRS), as well as {sup 18}F-fluoro-ethyl-tyrosine positron emission tomography ({sup 18}F-FET/PET). We have discussed the pertinent differences between childhood and adult BSGs, imaging mimics, prognostic factors and briefly reviewed the treatment options of these tumours.

  17. Delayed neuronal cell death in brainstem after transient brainstem ischemia in gerbils

    Directory of Open Access Journals (Sweden)

    Hakuba Nobuhiro

    2010-09-01

    Full Text Available Abstract Background Because of the lack of reproducible brainstem ischemia models in rodents, the temporal profile of ischemic lesions in the brainstem after transient brainstem ischemia has not been evaluated intensively. Previously, we produced a reproducible brainstem ischemia model of Mongolian gerbils. Here, we showed the temporal profile of ischemic lesions after transient brainstem ischemia. Results Brainstem ischemia was produced by occlusion of the bilateral vertebral arteries just before their entry into the transverse foramina of the cervical vertebrae of Mongolian gerbils. Animals were subjected to brainstem ischemia for 15 min, and then reperfused for 0 d (just after ischemia, 1 d, 3 d and 7 d (n = 4 in each group. Sham-operated animals (n = 4 were used as control. After deep anesthesia, the gerbils were perfused with fixative for immunohistochemical investigation. Ischemic lesions were detected by immunostaining for microtubule-associated protein 2 (MAP2. Just after 15-min brainstem ischemia, ischemic lesions were detected in the lateral vestibular nucleus and the ventral part of the spinal trigeminal nucleus, and these ischemic lesions disappeared one day after reperfusion in all animals examined. However, 3 days and 7 days after reperfusion, ischemic lesions appeared again and clusters of ionized calcium-binding adapter molecule-1(IBA-1-positive cells were detected in the same areas in all animals. Conclusion These results suggest that delayed neuronal cell death took place in the brainstem after transient brainstem ischemia in gerbils.

  18. Detection of brainstem involvemetn in multiple sclerosis

    International Nuclear Information System (INIS)

    Martinelli, V.; Comi, G.; Filippi, M.; Sora, M.G.N.; Magnani, G.; Locatelli, T.; Visciani, A.; Scotti, G.; Canal, N.

    1989-01-01

    The Gradient Refocusing Technique, which seppresses the influence of cerebrospinal fluis (GSF) and vascular motion artifact on MRI sensitivity, is applied combined with Brainstem Auditory Evoked Potentials (BAEPs) and median Somatosensory Evoked Potentials (SEPs) in the evaluation of the brainstem in 30 MS patients with clinical signs of involvement of this structure in order to reevaluate the sensitivity of these techniques. (Author). 2 refs.; 1 tab

  19. Coronary plaque quantification and fractional flow reserve by coronary computed tomography angiography identify ischaemia-causing lesions

    DEFF Research Database (Denmark)

    Gaur, Sara; Øvrehus, Kristian Altern; Dey, Damini

    2016-01-01

    AIMS: Coronary plaque characteristics are associated with ischaemia. Differences in plaque volumes and composition may explain the discordance between coronary stenosis severity and ischaemia. We evaluated the association between coronary stenosis severity, plaque characteristics, coronary computed...... tomography angiography (CTA)-derived fractional flow reserve (FFRCT), and lesion-specific ischaemia identified by FFR in a substudy of the NXT trial (Analysis of Coronary Blood Flow Using CT Angiography: Next Steps). METHODS AND RESULTS: Coronary CTA stenosis, plaque volumes, FFRCT, and FFR were assessed...

  20. Dental plaque identification at home

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003426.htm Dental plaque identification at home To use the sharing ... a sticky substance that collects around and between teeth. The home dental plaque identification test shows where ...

  1. Influence of Adaptive Statistical Iterative Reconstruction on coronary plaque analysis in coronary computed tomography angiography.

    Science.gov (United States)

    Precht, Helle; Kitslaar, Pieter H; Broersen, Alexander; Dijkstra, Jouke; Gerke, Oke; Thygesen, Jesper; Egstrup, Kenneth; Lambrechtsen, Jess

    The purpose of this study was to study the effect of iterative reconstruction (IR) software on quantitative plaque measurements in coronary computed tomography angiography (CCTA). Thirty patients with a three clinical risk factors for coronary artery disease (CAD) had one CCTA performed. Images were reconstructed using FBP, 30% and 60% adaptive statistical IR (ASIR). Coronary plaque analysis was performed as per patient and per vessel (LM, LAD, CX and RCA) measurements. Lumen and vessel volumes and plaque burden measurements were based on automatic detected contours in each reconstruction. Lumen and plaque intensity measurements and HU based plaque characterization were based on corrected contours copied to each reconstruction. No significant changes between FBP and 30% ASIR were found except for lumen- (-2.53 HU) and plaque intensities (-1.28 HU). Between FBP and 60% ASIR the change in total volume showed an increase of 0.94%, 4.36% and 2.01% for lumen, plaque and vessel, respectively. The change in total plaque burden between FBP and 60% ASIR was 0.76%. Lumen and plaque intensities decreased between FBP and 60% ASIR with -9.90 HU and -1.97 HU, respectively. The total plaque component volume changes were all small with a maximum change of -1.13% of necrotic core between FBP and 60% ASIR. Quantitative plaque measurements only showed modest differences between FBP and the 60% ASIR level. Differences were increased lumen-, vessel- and plaque volumes, decreased lumen- and plaque intensities and a small percentage change in the individual plaque component volumes. Copyright © 2016 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

  2. Relationship between brainstem neurodegeneration and clinical impairment in traumatic spinal cord injury

    Directory of Open Access Journals (Sweden)

    Patrick Grabher

    2017-01-01

    Conclusion: Neurodegeneration, indicated by volume loss and myelin reductions, is evident in major brainstem pathways and nuclei following traumatic SCI; the magnitude of these changes relating to clinical impairment. Thus, quantitative MRI protocols offer new targets, which may be used as neuroimaging biomarkers in treatment trials.

  3. SU-E-T-15: A Comparison of COMS and EP917 Eye Plaque Applicators Using Different Radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Aryal, P; Molloy, JA [University of Kentucky, Lexington, KY (United States); Rivard, MJ [Tufts University School of Medicine, Boston, MA (United States)

    2015-06-15

    Purpose: To investigate the effect of plaque design and radionuclides on eye plaque dosimetry. Methods: The Monte Carlo N-particle Code version 6 (MCNP6) was used for radiation transport simulations. The 14 mm and 16 mm diameter COMS plaques and the model EP917 plaque were simulated using brachytherapy seeds containing I-125, Pd-103, and Cs-131 radionuclides. The origin was placed at the scleral inner surface. The central axis (CAX) doses of both COMS plaques at −1 mm, 0 mm, 1 mm, 2 mm, 5 mm, 10 mm, 15 mm, 20 mm, and 22.6 mm were compared to the model EP917 plaque. Dose volume histograms (DVHs) were also created for both COMS plaques for the tumor and outer sclera then compared to results for the model EP917 plaque. Results: For all radionuclides, the EP917 plaque delivered higher dose (max 343%) compared to the COMS plaques, except for the 14 mm COMS plaque with Cs-131 at 1 mm and 2 mm depths from outer sclera surface. This could be due to source design. For all radionuclides, the 14 mm COMS plaque delivered higher doses compared to the 16 mm COMS plaque for the depths up to 5 mm. Dose differences were not significant beyond depths of 10 mm due to ocular lateral scatter for the different plaque designs. Tumor DVHs for the 16 mm COMS plaque with Cs-131 provided better dose homogeneity and conformity compared to other COMS plaques with I-125 and Pd-103. Using Pd-103, DVHs for the 16 mm COMS plaque delivered less dose to outer sclera compared to other plaques. Conclusion: This study identified improved tumor homogeneity upon considering radionuclides and plaque designs, and found that scleral dose with the model EP917 plaque was higher than for the 16 mm COMS plaque for all the radionuclides studied.

  4. Gamma Knife Treatment of Brainstem Metastases

    Science.gov (United States)

    Peterson, Halloran E.; Larson, Erik W.; Fairbanks, Robert K.; MacKay, Alexander R.; Lamoreaux, Wayne T.; Call, Jason A.; Carlson, Jonathan D.; Ling, Benjamin C.; Demakas, John J.; Cooke, Barton S.; Peressini, Ben; Lee, Christopher M.

    2014-01-01

    The management of brainstem metastases is challenging. Surgical treatment is usually not an option, and chemotherapy is of limited utility. Stereotactic radiosurgery has emerged as a promising palliative treatment modality in these cases. The goal of this study is to assess our single institution experience treating brainstem metastases with Gamma Knife radiosurgery (GKRS). This retrospective chart review studied 41 patients with brainstem metastases treated with GKRS. The most common primary tumors were lung, breast, renal cell carcinoma, and melanoma. Median age at initial treatment was 59 years. Nineteen (46%) of the patients received whole brain radiation therapy (WBRT) prior to or concurrent with GKRS treatment. Thirty (73%) of the patients had a single brainstem metastasis. The average GKRS dose was 17 Gy. Post-GKRS overall survival at six months was 42%, at 12 months was 22%, and at 24 months was 13%. Local tumor control was achieved in 91% of patients, and there was one patient who had a fatal brain hemorrhage after treatment. Karnofsky performance score (KPS) >80 and the absence of prior WBRT were predictors for improved survival on multivariate analysis (HR 0.60 (p = 0.02), and HR 0.28 (p = 0.02), respectively). GKRS was an effective treatment for brainstem metastases, with excellent local tumor control. PMID:24886816

  5. Clinical analysis of the outcome of patients with brainstem hemorrhage

    International Nuclear Information System (INIS)

    Arimoto, Hirohiko; Takasato, Yoshio; Masaoka, Hiroyuki

    2008-01-01

    To identify prognostic factors in patients with brainstem hemorrhage, we analyzed their clinical symptoms and laboratory data on admission to our hospital. In 70 patients with brainstem hemorrhage (51 men and 19 women aged 29-93, with a mean of 59 gears) who had been admitted to our hospital from 1995 to 2000, we statistically evaluated the association of the outcome with their age and clinical symptoms on admission, blood glucose levels and white blood counts within 6 hours of admission, and the volume and extent of hematoma, concomitant hydrocephalus, and intraventricular perforation on admission CT scans. The mortality tended to be higher, but not significantly (P=0.07), in patients aged 70 years or older (83%) than in those aged less than 70 years (55%). Quadriplegia or decerebrate rigidity (P 2 or higher (P<0.01) on admission were significantly correlated with the prognosis. Hematoma volumes of 6 ml or larger on CT scans were most strongly correlated with the prognosis (P<0.001). Central hematoma and hematoma with extension to the midbrain, thalamus, or medulla oblongata (P<0.05), as well as hemorrhage complicated by hydrocephalus or intraventricular perforation (P<0.01), were correlated with the prognosis. (author)

  6. Brainstem tumors: Current management and future directions

    Directory of Open Access Journals (Sweden)

    Pablo F Recinos

    2012-01-01

    Full Text Available Tumors arising in the brainstem comprise 10-20% of all pediatric central nervous system (CNS tumors and account for a small percentage in adults. The prognosis for these tumors was considered uniformly poor prior to the era of modern neuroimaging and the location was fraught with disaster being considered a ′no man′s land′ for neurosurgeons. Following the introduction of advanced imaging modalities and neurophysiological monitoring, striking progress has occurred in the management of these lesions. Brainstem tumors are presently classified based on their anatomic location, focality, and histopathology. This article reviews the current classification of brainstem tumors, current management options, and future directions in the treatment for these rare tumors.

  7. Is enhanced MRI helpful in brainstem infarction?

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Y. M.; Shin, G. H.; Choi, W. S. [Kyung Hee University Hospital, Seoul (Korea, Republic of)

    1994-12-15

    To determine the role of MR contrast enhancement in evaluating time course of brainstem infarction. MR imaging with IV administration of gadopentetate dimeglumine was retrospectively reviewed in 43 patients with clinically and radiologically documented brainstem infarctions. The pattern of infarction was classified into spotty and patchy. Presence of parenchymal enhancement in infarction was evaluated. By location, there were 34 pontine, 3 midbrain, 6 medullary infarctions. The age of the infarctions ranged from 1 day to 9 months, with 5 patients scanned within 3 days and 10 scanned within 2 weeks of clinical ictus. Abnormalities on T2-weighted images were encountered in every case, with spotty pattern in 14 cases and patchy pattern in 29 cases. Parenchymal contrast enhancement was seen in 9 cases(20%), primarily occurring between days 8 and 20. MR contrast enhancement in brainstem infarction was infrequent that it may not be useful in the estimation of the age of infarction.

  8. Stereotactic Radiosurgery for Brainstem Metastases: An International Cooperative Study to Define Response and Toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Trifiletti, Daniel M., E-mail: daniel.trifiletti@gmail.com [Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia (United States); Lee, Cheng-Chia [Department of Neurosurgery, Neurological Institute, Taipei Veteran General Hospital, Taipei, Taiwan (China); Kano, Hideyuki; Cohen, Jonathan [Department of Neurological Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (United States); Janopaul-Naylor, James; Alonso-Basanta, Michelle; Lee, John Y.K. [Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania (United States); Simonova, Gabriela; Liscak, Roman [Department of Radiation and Stereotactic Neurosurgery, Na Homolce Hospital, Prague (Czech Republic); Wolf, Amparo; Kvint, Svetlana [Department of Neurosurgery, New York University Lagone Medical Center, New York, New York (United States); Grills, Inga S.; Johnson, Matthew [Department of Radiation Oncology, Beaumont Health System, Royal Oak, Michigan (United States); Liu, Kang-Du; Lin, Chung-Jung [Department of Neurosurgery, Neurological Institute, Taipei Veteran General Hospital, Taipei, Taiwan (China); Mathieu, David; Héroux, France [Division of Neurosurgery, Université de Sherbrooke, Centre de recherche du CHUS, Sherbrooke, Québec (Canada); Silva, Danilo; Sharma, Mayur [Department of Neurosurgery, Cleveland Clinic, Cleveland, Ohio (United States); Cifarelli, Christopher P. [Departments of Neurosurgery and Radiation Oncology, West Virginia University, Morgantown, West Virginia (United States); and others

    2016-10-01

    Purpose: To pool data across multiple institutions internationally and report on the cumulative experience of brainstem stereotactic radiosurgery (SRS). Methods and Materials: Data on patients with brainstem metastases treated with SRS were collected through the International Gamma Knife Research Foundation. Clinical, radiographic, and dosimetric characteristics were compared for factors prognostic for local control (LC) and overall survival (OS) using univariate and multivariate analyses. Results: Of 547 patients with 596 brainstem metastases treated with SRS, treatment of 7.4% of tumors resulted in severe SRS-induced toxicity (grade ≥3, increased odds with increasing tumor volume, margin dose, and whole-brain irradiation). Local control at 12 months after SRS was 81.8% and was improved with increasing margin dose and maximum dose. Overall survival at 12 months after SRS was 32.7% and impacted by age, gender, number of metastases, tumor histology, and performance score. Conclusions: Our study provides additional evidence that SRS has become an option for patients with brainstem metastases, with an excellent benefit-to-risk ratio in the hands of experienced clinicians. Prior whole-brain irradiation increases the risk of severe toxicity in brainstem metastasis patients undergoing SRS.

  9. La pelade par plaques

    Science.gov (United States)

    Spano, Frank; Donovan, Jeff C.

    2015-01-01

    Résumé Objectif Présenter aux médecins de famille des renseignements de base pour faire comprendre l’épidémiologie, la pathogenèse, l’histologie et l’approche clinique au diagnostic de la pelade par plaques. Sources des données Une recension a été effectuée dans PubMed pour trouver des articles pertinents concernant la pathogenèse, le diagnostic et le pronostic de la pelade par plaques. Message principal La pelade par plaques est une forme de perte pileuse auto-immune dont la prévalence durant une vie est d’environ 2 %. Des antécédents personnels ou familiaux de troubles auto-immuns concomitants, comme le vitiligo ou une maladie de la thyroïde, peuvent être observés dans un petit sous-groupe de patients. Le diagnostic peut souvent être posé de manière clinique en se fondant sur la perte de cheveux non cicatricielle et circulaire caractéristique, accompagnée de cheveux en « point d’exclamation » en périphérie chez ceux dont le problème en est aux premiers stades. Le diagnostic des cas plus complexes ou des présentations inhabituelles peut être facilité par une biopsie et un examen histologique. Le pronostic varie largement et de mauvais résultats sont associés à une apparition à un âge précoce, une perte importante, la variante ophiasis, des changements aux ongles, des antécédents familiaux ou des troubles auto-immuns concomitants. Conclusion La pelade par plaques est une forme auto-immune de perte de cheveux périodiquement observée en soins primaires. Les médecins de famille sont bien placés pour identifier la pelade par plaques, déterminer la gravité de la maladie et poser le diagnostic différentiel approprié. De plus, ils sont en mesure de renseigner leurs patients à propos de l’évolution clinique de la maladie ainsi que du pronostic général selon le sous-type de patients.

  10. Giant tubercular brainstem abscess: A case report

    Directory of Open Access Journals (Sweden)

    Pragati Chigurupati

    2014-01-01

    Full Text Available Tubercular brain abscesses are uncommon and tubercular brainstem abscesses are rarely reported. Most of these cases occur in immunocompromised patients. We report a case of giant brainstem abscess in a 5-year-old human immunodeficiency virus-seronegative female child who presented with complaints of headache, diplopia and unsteadiness of gait since 6 months. Diagnosis was made by a magnetic resonance imaging scan of brain. The patient demonstrated a remarkable clinical recovery after microsurgery combined with a course of antituberculous therapy. Microbiological and histological findings confirmed the diagnosis of a tuberculous abscess.

  11. CT virtual intravascular endoscopy assessment of coronary artery plaques: A preliminary study

    International Nuclear Information System (INIS)

    Sun Zhonghua; Dimpudus, Franky Jacobus; Nugroho, Johanes; Adipranoto, Jeffrey Daniel

    2010-01-01

    Purpose: The purpose of this study was to investigate the potential value of CT virtual intravascular endoscopy (VIE) in the visualization and assessment of coronary plaques in patients suspected of coronary artery disease. Materials and methods: 20 (13 men, 7 women, mean age 54 years) consecutive patients with suspected coronary artery disease undergoing 64-slice CT angiography were included in the study. Four main coronary artery branches were assessed with regard to the presence of coronary plaques based on 2D axial, multiplanar reformation, 3D volume rendering and VIE visualizations. The coronary plaques were characterized into calcified, noncalcified and mixed plaques. The intraluminal appearances of these coronary plaques were demonstrated with VIE images and correlated with 2D and 3D images to determine the diagnostic value of VIE for the assessment of the plaques. Results: VIE was able to identify and demonstrate the intraluminal appearances of coronary plaques in 18 patients involving 32 coronary artery branches which were shown as an irregularly intraluminal protruding sign in extensively calcified plaques and smooth protruding appearance in noncalcified or focally calcified plaques. An irregular intraluminal appearance was also noticed in the presence of mixed plaques due to variable components with different CT attenuations contained within the plaques. VIE accurately confirmed the degree of coronary stenosis or occlusion despite the presence of heavy calcification. Conclusion: VIE could be used as a complementary tool to conventional CT visualizations for the analysis of luminal changes and assessment of disease extent caused by the coronary plaques.

  12. Bayesian segmentation of brainstem structures in MRI

    DEFF Research Database (Denmark)

    Iglesias, Juan Eugenio; Van Leemput, Koen; Bhatt, Priyanka

    2015-01-01

    the brainstem structures in novel scans. Thanks to the generative nature of the scheme, the segmentation method is robust to changes in MRI contrast or acquisition hardware. Using cross validation, we show that the algorithm can segment the structures in previously unseen T1 and FLAIR scans with great accuracy...

  13. Neuromyelitis Optica Lesion Mimicking Brainstem Glioma

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2007-12-01

    Full Text Available A 12-year-old girl who presented with weakness of the left extremities and right sided sixth cranial nerve palsy had neuromyelitis optica (NMO mistaken for brainstem glioma on MRI, in a report from Brain Research Institute, Yonsei University College of Medicine,Seoul, Republic of KoreaNeuromyelitis Optica, Optic-Spinal Syndrome, Spectroscopy.

  14. Air pollution is associated with brainstem auditory nuclei pathology and delayed brainstem auditory evoked potentials.

    Science.gov (United States)

    Calderón-Garcidueñas, Lilian; D'Angiulli, Amedeo; Kulesza, Randy J; Torres-Jardón, Ricardo; Osnaya, Norma; Romero, Lina; Keefe, Sheyla; Herritt, Lou; Brooks, Diane M; Avila-Ramirez, Jose; Delgado-Chávez, Ricardo; Medina-Cortina, Humberto; González-González, Luis Oscar

    2011-06-01

    We assessed brainstem inflammation in children exposed to air pollutants by comparing brainstem auditory evoked potentials (BAEPs) and blood inflammatory markers in children age 96.3±8.5 months from highly polluted (n=34) versus a low polluted city (n=17). The brainstems of nine children with accidental deaths were also examined. Children from the highly polluted environment had significant delays in wave III (t(50)=17.038; p7.501; p<0.0001), consisting with delayed central conduction time of brainstem neural transmission. Highly exposed children showed significant evidence of inflammatory markers and their auditory and vestibular nuclei accumulated α synuclein and/or β amyloid(1-42). Medial superior olive neurons, critically involved in BAEPs, displayed significant pathology. Children's exposure to urban air pollution increases their risk for auditory and vestibular impairment. Copyright © 2011 ISDN. Published by Elsevier Ltd. All rights reserved.

  15. Veins in plaques of multiple sclerosis patients - a longitudinal magnetic resonance imaging study at 7 Tesla

    Energy Technology Data Exchange (ETDEWEB)

    Dal-Bianco, Assunta; Auff, Eduard; Leutmezer, Fritz; Vass, Karl [Medical University of Vienna, Department of Neurology, Wien (Austria); Hametner, Simon [Medical University of Vienna, Center for Brain Research, Wien (Austria); Grabner, Guenther; Schernthaner, Melanie; Kronnerwetter, Claudia; Trattnig, Siegfried [Medical University of Vienna, Department of Radiology, Wien (Austria); Reitner, Andreas; Vass, Clemens; Kircher, Karl [Medical University of Vienna, Department of Ophthalmology, Wien (Austria)

    2015-10-15

    To monitor the venous volumes in plaques of patients with multiple sclerosis (MS) compared to an age-matched control group over a period of 3.5 years. Ten MS patients underwent an annual neurological examination and MRI. Susceptibility-weighted imaging (SWI) combined with fluid-attenuated inversion recovery (FLAIR) or FLAIR-like contrast at 7 Tesla (7 T) magnetic resonance imaging (MRI) was used for manual segmentation of veins in plaques, in the normal-appearing white matter (NAWM) and in location-matched white matter of 9 age-matched controls. Venous volume to tissue volume ratio was assessed for each time point in order to describe the dynamics of venous volumes in MS plaques over time. MS plaques, which were newly detected during the study period, showed significantly higher venous volumes compared to the preplaque area 1 year before plaque detection and the corresponding NAWM regions. Venous volumes in established MS plaques, which were present already in the first scans, were significantly higher compared to the NAWM and controls. Our data underpin a relation of veins and plaque development in MS and reflect increased apparent venous calibers due to increased venous diameters or increased oxygen consumption in early MS plaques. (orig.)

  16. Veins in plaques of multiple sclerosis patients - a longitudinal magnetic resonance imaging study at 7 Tesla

    International Nuclear Information System (INIS)

    Dal-Bianco, Assunta; Auff, Eduard; Leutmezer, Fritz; Vass, Karl; Hametner, Simon; Grabner, Guenther; Schernthaner, Melanie; Kronnerwetter, Claudia; Trattnig, Siegfried; Reitner, Andreas; Vass, Clemens; Kircher, Karl

    2015-01-01

    To monitor the venous volumes in plaques of patients with multiple sclerosis (MS) compared to an age-matched control group over a period of 3.5 years. Ten MS patients underwent an annual neurological examination and MRI. Susceptibility-weighted imaging (SWI) combined with fluid-attenuated inversion recovery (FLAIR) or FLAIR-like contrast at 7 Tesla (7 T) magnetic resonance imaging (MRI) was used for manual segmentation of veins in plaques, in the normal-appearing white matter (NAWM) and in location-matched white matter of 9 age-matched controls. Venous volume to tissue volume ratio was assessed for each time point in order to describe the dynamics of venous volumes in MS plaques over time. MS plaques, which were newly detected during the study period, showed significantly higher venous volumes compared to the preplaque area 1 year before plaque detection and the corresponding NAWM regions. Venous volumes in established MS plaques, which were present already in the first scans, were significantly higher compared to the NAWM and controls. Our data underpin a relation of veins and plaque development in MS and reflect increased apparent venous calibers due to increased venous diameters or increased oxygen consumption in early MS plaques. (orig.)

  17. Presbycusis and auditory brainstem responses: a review

    Directory of Open Access Journals (Sweden)

    Shilpa Khullar

    2011-06-01

    Full Text Available Age-related hearing loss or presbycusis is a complex phenomenon consisting of elevation of hearing levels as well as changes in the auditory processing. It is commonly classified into four categories depending on the cause. Auditory brainstem responses (ABRs are a type of early evoked potentials recorded within the first 10 ms of stimulation. They represent the synchronized activity of the auditory nerve and the brainstem. Some of the changes that occur in the aging auditory system may significantly influence the interpretation of the ABRs in comparison with the ABRs of the young adults. The waves of ABRs are described in terms of amplitude, latencies and interpeak latency of the different waves. There is a tendency of the amplitude to decrease and the absolute latencies to increase with advancing age but these trends are not always clear due to increase in threshold with advancing age that act a major confounding factor in the interpretation of ABRs.

  18. Optimization of 125I ophthalmic plaque brachytherapy

    International Nuclear Information System (INIS)

    Astrahan, M.A.; Luxton, G.; Jozsef, G.; Liggett, P.E.; Petrovich, Z.

    1990-01-01

    Episcleral plaques containing 125 I sources are often used in the treatment of ocular melanoma. Within four years post-treatment, however, the majority of patients experience some visual loss due to radiation retinopathy. The high incidence of late complications suggests that careful treatment optimization may lead to improved outcome. The goal of optimization would be to reduce the magnitude of vision-limiting complications without compromising tumor control. We have developed a three-dimensional computer model for ophthalmic plaque therapy which permits us to explore the potential of various optimization strategies. One simple strategy which shows promise is to maximize the ratio of dose to the tumor apex (T) compared to dose to the macula (M). By modifying the parameters of source location, activity distribution, source orientation, and shielding we find that the calculated T:M ratio can be varied by a factor of 2 for a common plaque design and posterior tumor location. Margins and dose to the tumor volume remain essentially unchanged

  19. Effects of Caffeine on Auditory Brainstem Response

    Directory of Open Access Journals (Sweden)

    Saleheh Soleimanian

    2008-06-01

    Full Text Available Background and Aim: Blocking of the adenosine receptor in central nervous system by caffeine can lead to increasing the level of neurotransmitters like glutamate. As the adenosine receptors are present in almost all brain areas like central auditory pathway, it seems caffeine can change conduction in this way. The purpose of this study was to evaluate the effects of caffeine on latency and amplitude of auditory brainstem response(ABR.Materials and Methods: In this clinical trial study 43 normal 18-25 years old male students were participated. The subjects consumed 0, 2 and 3 mg/kg BW caffeine in three different sessions. Auditory brainstem responses were recorded before and 30 minute after caffeine consumption. The results were analyzed by Friedman and Wilcoxone test to assess the effects of caffeine on auditory brainstem response.Results: Compared to control group the latencies of waves III,V and I-V interpeak interval of the cases decreased significantly after 2 and 3mg/kg BW caffeine consumption. Wave I latency significantly decreased after 3mg/kg BW caffeine consumption(p<0.01. Conclusion: Increasing of the glutamate level resulted from the adenosine receptor blocking brings about changes in conduction in the central auditory pathway.

  20. Stereotactic radiosurgery for brainstem metastases: Survival, tumor control, and patient outcomes

    International Nuclear Information System (INIS)

    Hussain, Aamir; Brown, Paul D.; Stafford, Scott L.; Pollock, Bruce E.

    2007-01-01

    Purpose: Patients with brainstem metastases have limited treatment options. In this study, we reviewed outcomes after stereotactic radiosurgery (SRS) in the management of patients with brainstem metastases. Methods and Materials: Records were reviewed of 22 consecutive patients presenting with brainstem metastases who underwent SRS. The most frequent primary malignancy was the lung (n = 11), followed by breast (n = 3) and kidney (n = 2). Three patients (14%) also underwent whole-brain radiation therapy (WBRT). The median tumor volume was 0.9 mL (range, 0.1-3.3 mL); the median tumor margin dose was 16 Gy (range, 14-23 Gy). Results: Median survival time after SRS was 8.5 months. Although local tumor control was achieved in all patients with imaging follow-up (n = 19), 5 patients died from development and progression of new brain metastases. Two patients (9%) had symptom improvement after SRS, whereas 1 patient (5%) developed a new hemiparesis after SRS. Conclusions: Radiosurgery is safe and provides a high local tumor control rate for patients with small brainstem metastases. Patients with limited systemic disease and good performance status should be strongly considered for SRS

  1. Individual differences in brainstem and basal ganglia structure predict postural control and balance loss in young and older adults.

    Science.gov (United States)

    Boisgontier, Matthieu P; Cheval, Boris; Chalavi, Sima; van Ruitenbeek, Peter; Leunissen, Inge; Levin, Oron; Nieuwboer, Alice; Swinnen, Stephan P

    2017-02-01

    It remains unclear which specific brain regions are the most critical for human postural control and balance, and whether they mediate the effect of age. Here, associations between postural performance and corticosubcortical brain regions were examined in young and older adults using multiple structural imaging and linear mixed models. Results showed that of the regions involved in posture, the brainstem was the strongest predictor of postural control and balance: lower brainstem volume predicted larger center of pressure deviation and higher odds of balance loss. Analyses of white and gray matter in the brainstem showed that the pedunculopontine nucleus area appeared to be critical for postural control in both young and older adults. In addition, the brainstem mediated the effect of age on postural control, underscoring the brainstem's fundamental role in aging. Conversely, lower basal ganglia volume predicted better postural performance, suggesting an association between greater neural resources in the basal ganglia and greater movement vigor, resulting in exaggerated postural adjustments. Finally, results showed that practice, shorter height and heavier weight (i.e., higher body mass index), higher total physical activity, and larger ankle active (but not passive) range of motion were predictive of more stable posture, irrespective of age. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Magnetic resonance imaging in the evaluation of the brainstem

    International Nuclear Information System (INIS)

    Han, J.S.; Bonstelle, C.T.; Kaufman, B.; Benson, J.E.; Alfidi, R.J.; Clampitt, M.; Van Dyke, C.; Huss, R.G.

    1984-01-01

    Magnetic resonance (MR) images of the brainstem region from 100 normal or asymptomatic individuals were reviewed in addition to those of 17 patients with intra-axial brainstem lesions and 15 patients with extra-axial masses around the brainstem. MR was able to demonstrate consistently the normal anatomy of the brainstem and adjacent cisterns, though the distinction between gray and white matter was seldom possible with the present technology. Masses in and around the brainstem were all accurately identified on MR and its sensitivity was superior to that of x-ray computed tomography (CT). These study results show that despite its technical limitations, MR is presently the examination of choice for the evaluation of brainstem abnormalities and eventually it will undoubtedly replace metrizamide CT cisternography

  3. Quantitative assessment of changes in carotid plaques during cilostazol administration using three-dimensional ultrasonography and non-gated magnetic resonance plaque imaging

    Energy Technology Data Exchange (ETDEWEB)

    Yamaguchi, Mao; Ohba, Hideki; Mori, Kiyofumi; Narumi, Shinsuke; Katsura, Noriyuki; Ohura, Kazumasa; Terayama, Yasuo [Iwate Medical University, Department of Neurology and Gerontology, Morioka (Japan); Sasaki, Makoto; Kudo, Kohsuke [Iwate Medical University, Division of Ultrahigh Field MRI, Institute for Biomedical Sciences, Morioka (Japan)

    2012-09-15

    Cilostazol, an antiplatelet agent, is reported to induce the regression of atherosclerotic changes. However, its effects on carotid plaques are unknown. Hence, we quantitatively investigated the changes that occur within carotid plaques during cilostazol administration using three-dimensional (3D) ultrasonography (US) and non-gated magnetic resonance (MR) plaque imaging. We prospectively examined 16 consecutive patients with carotid stenosis. 3D-US and T1-weighted MR plaque imaging were performed at baseline and 6 months after initiating cilostazol therapy (200 mg/day). We measured the volume and grayscale median (GSM) of the plaques from 3D-US data. We also calculated the contrast ratio (CR) of the carotid plaque against the adjacent muscle and areas of the intraplaque components: fibrous tissue, lipid, and hemorrhage components. The plaque volume on US decreased significantly (median at baseline and 6 months, 0.23 and 0.21 cm{sup 3}, respectively; p = 0.03). In the group exhibiting a plaque volume reduction of more than 10%, GSM on US increased significantly (24.8 and 71.5, respectively; p = 0.04) and CR on MRI decreased significantly (1.13 and 1.04, respectively; p = 0.02). In this group, in addition, the percent area of the fibrous component on MRI increased significantly (68.6% and 79.4%, respectively; p = 0.02), while those of the lipid and hemorrhagic components decreased (24.9% and 20.5%, respectively; p = 0.12) (1.0% and 0.0%, respectively; p = 0.04). There were no substantial changes in intraplaque characteristics in either US or MRI in the other group. 3D-US and MR plaque imaging can quantitatively detect changes in the size and composition of carotid plaques during cilostazol therapy. (orig.)

  4. Intraplaque Hemorrhage and the Plaque Surface in Carotid Atherosclerosis: The Plaque At RISK Study (PARISK)

    NARCIS (Netherlands)

    van Dijk, A. C.; Truijman, M. T. B.; Hussain, B.; Zadi, T.; Saiedie, G.; de Rotte, A. A. J.; Liem, M. I.; van der Steen, A. F. W.; Daemen, M. J. A. P.; Koudstaal, P. J.; Nederkoorn, P. J.; Hendrikse, J.; Kooi, M. E.; van der Lugt, A.

    2015-01-01

    An important characteristic of vulnerable plaque, intraplaque hemorrhage, may predict plaque rupture. Plaque rupture can be visible on noninvasive imaging as a disruption of the plaque surface. We investigated the association between intraplaque hemorrhage and disruption of the plaque surface. We

  5. Characterising human atherosclerotic carotid plaque tissue composition and morphology using combined spectroscopic and imaging modalities.

    Science.gov (United States)

    Barrett, Hilary E; Mulvihill, John J; Cunnane, Eoghan M; Walsh, Michael T

    2015-01-01

    Calcification is a marked pathological component in carotid artery plaque. Studies have suggested that calcification may induce regions of high stress concentrations therefore increasing the potential for rupture. However, the mechanical behaviour of the plaque under the influence of calcification is not fully understood. A method of accurately characterising the calcification coupled with the associated mechanical plaque properties is needed to better understand the impact of calcification on the mechanical behaviour of the plaque during minimally invasive treatments. This study proposes a comparison of biochemical and structural characterisation methods of the calcification in carotid plaque specimens to identify plaque mechanical behaviour. Biochemical analysis, by Fourier Transform Infrared (FTIR) spectroscopy, was used to identify the key components, including calcification, in each plaque sample. However, FTIR has a finite penetration depth which may limit the accuracy of the calcification measurement. Therefore, this FTIR analysis was coupled with the identification of the calcification inclusions located internally in the plaque specimen using micro x-ray computed tomography (μX-CT) which measures the calcification volume fraction (CVF) to total tissue content. The tissue characterisation processes were then applied to the mechanical material plaque properties acquired from experimental circumferential loading of human carotid plaque specimen for comparison of the methods. FTIR characterised the degree of plaque progression by identifying the functional groups associated with lipid, collagen and calcification in each specimen. This identified a negative relationship between stiffness and 'lipid to collagen' and 'calcification to collagen' ratios. However, μX-CT results suggest that CVF measurements relate to overall mechanical stiffness, while peak circumferential strength values may be dependent on specific calcification geometries. This study

  6. Speech Evoked Auditory Brainstem Response in Stuttering

    Directory of Open Access Journals (Sweden)

    Ali Akbar Tahaei

    2014-01-01

    Full Text Available Auditory processing deficits have been hypothesized as an underlying mechanism for stuttering. Previous studies have demonstrated abnormal responses in subjects with persistent developmental stuttering (PDS at the higher level of the central auditory system using speech stimuli. Recently, the potential usefulness of speech evoked auditory brainstem responses in central auditory processing disorders has been emphasized. The current study used the speech evoked ABR to investigate the hypothesis that subjects with PDS have specific auditory perceptual dysfunction. Objectives. To determine whether brainstem responses to speech stimuli differ between PDS subjects and normal fluent speakers. Methods. Twenty-five subjects with PDS participated in this study. The speech-ABRs were elicited by the 5-formant synthesized syllable/da/, with duration of 40 ms. Results. There were significant group differences for the onset and offset transient peaks. Subjects with PDS had longer latencies for the onset and offset peaks relative to the control group. Conclusions. Subjects with PDS showed a deficient neural timing in the early stages of the auditory pathway consistent with temporal processing deficits and their abnormal timing may underlie to their disfluency.

  7. Brainstem auditory evoked potentials in horses

    Directory of Open Access Journals (Sweden)

    Juliana Almeida Nogueira da Gama

    2016-04-01

    Full Text Available ABSTRACT: The brainstem auditory evoked potential (BAEP evaluates the integrity of the auditory pathways to the brainstem. The aim of this study was to evoke BAEPs in 21 clinically normal horses. The animals were sedated with detomidine hydrochloride (0.013mg.kg-1 BW. Earphones were inserted and rarefaction clicks at 90 dB and noise masking at 40 dB were used. After performing the test, the latencies of waves (I, II, III, IV, and V and interpeaks(I-III, III-V, and I-V were identified. The mean latencies of the waves were as follows: wave I, 2.4 ms; wave II, 2.24 ms; wave III, 3.61ms; wave IV, 4.61ms; and wave V, 5.49ms. The mean latencies of the interpeaks were as follows: I-III, 1.37ms; III-V, 1.88ms; and I-V, 3.26ms. This is the first study using BAEPs in horses in Brazil, and the observed latencies will be used as normative data for the interpretation of tests performed on horses with changes related to auditory system or neurologic abnormalities.

  8. Intraplaque hemorrhage is associated with higher structural stresses in human atherosclerotic plaques: an in vivo MRI-based 3d fluid-structure interaction study

    OpenAIRE

    Huang, Xueying; Teng, Zhongzhao; Canton, Gador; Ferguson, Marina; Yuan, Chun; Tang, Dalin

    2010-01-01

    Abstract Background Studies using medical images have shown that intraplaque hemorrhage may accelerate plaque progression and may produce a stimulus for atherosclerosis development by increasing lipid core and plaque volume and creating new destabilizing factors. Image-based 3D computational models with fluid-structure interactions (FSI) will be used to perform plaque mechanical analysis and investigate possible associations between intraplaque hemorrhage and both plaque wall stress (PWS) and...

  9. Optimal technique of linear accelerator–based stereotactic radiosurgery for tumors adjacent to brainstem

    International Nuclear Information System (INIS)

    Chang, Chiou-Shiung; Hwang, Jing-Min; Tai, Po-An; Chang, You-Kang; Wang, Yu-Nong; Shih, Rompin; Chuang, Keh-Shih

    2016-01-01

    Stereotactic radiosurgery (SRS) is a well-established technique that is replacing whole-brain irradiation in the treatment of intracranial lesions, which leads to better preservation of brain functions, and therefore a better quality of life for the patient. There are several available forms of linear accelerator (LINAC)–based SRS, and the goal of the present study is to identify which of these techniques is best (as evaluated by dosimetric outcomes statistically) when the target is located adjacent to brainstem. We collected the records of 17 patients with lesions close to the brainstem who had previously been treated with single-fraction radiosurgery. In all, 5 different lesion catalogs were collected, and the patients were divided into 2 distance groups—1 consisting of 7 patients with a target-to-brainstem distance of less than 0.5 cm, and the other of 10 patients with a target-to-brainstem distance of ≥ 0.5 and < 1 cm. Comparison was then made among the following 3 types of LINAC-based radiosurgery: dynamic conformal arcs (DCA), intensity-modulated radiosurgery (IMRS), and volumetric modulated arc radiotherapy (VMAT). All techniques included multiple noncoplanar beams or arcs with or without intensity-modulated delivery. The volume of gross tumor volume (GTV) ranged from 0.2 cm 3 to 21.9 cm 3 . Regarding the dose homogeneity index (HI ICRU ) and conformity index (CI ICRU ) were without significant difference between techniques statistically. However, the average CI ICRU = 1.09 ± 0.56 achieved by VMAT was the best of the 3 techniques. Moreover, notable improvement in gradient index (GI) was observed when VMAT was used (0.74 ± 0.13), and this result was significantly better than those achieved by the 2 other techniques (p < 0.05). For V 4 Gy of brainstem, both VMAT (2.5%) and IMRS (2.7%) were significantly lower than DCA (4.9%), both at the p < 0.05 level. Regarding V 2 Gy of normal brain, VMAT plans had attained 6.4 ± 5%; this was significantly better

  10. Endovascular treatment of brain-stem arteriovenous malformations: safety and efficacy

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H.M.; Wang, Y.H.; Chen, Y.F.; Huang, K.M. [Department of Medical Imaging, National Taiwan University Hospital, 7 Chung-Shan South Road, 10016, Taipei (Taiwan); Tu, Y.K. [Division of Neurosurgery, Department of Surgery, National Taiwan University Hospital, 7 Chung-Shan South Road, 1001, Taipei (Taiwan)

    2003-09-01

    Our purpose was to evaluate the safety and efficacy of endovascular treatment of brain-stem arteriovenous malformations (AVMs), reviewing six cases managed in the last 5 years. There were four patients who presented with bleeding, one with a progressive neurological deficit and one with obstructive hydrocephalus. Of the six patients, one showed 100%, one 90%, two 75% and two about 50% angiographic obliteration of the AVM after embolisation; the volume decreased about 75% on average. Five patients had a good outcome and one an acceptable outcome, with a mild postprocedure neurological deficit; none had further bleeding during midterm follow-up. Endovascular management of a brain-stem AVM may be an alternative to treatment such as radiosurgery and microsurgery in selected cases. It may be not as risky as previously thought. Embolisation can reduce the size of the AVM and possibly make it more treatable by radiosurgery and decrease the possibility of radiation injury. (orig.)

  11. Denitrification in human dental plaque

    Directory of Open Access Journals (Sweden)

    Verstraete Willy

    2010-03-01

    Full Text Available Abstract Background Microbial denitrification is not considered important in human-associated microbial communities. Accordingly, metabolic investigations of the microbial biofilm communities of human dental plaque have focused on aerobic respiration and acid fermentation of carbohydrates, even though it is known that the oral habitat is constantly exposed to nitrate (NO3- concentrations in the millimolar range and that dental plaque houses bacteria that can reduce this NO3- to nitrite (NO2-. Results We show that dental plaque mediates denitrification of NO3- to nitric oxide (NO, nitrous oxide (N2O, and dinitrogen (N2 using microsensor measurements, 15N isotopic labelling and molecular detection of denitrification genes. In vivo N2O accumulation rates in the mouth depended on the presence of dental plaque and on salivary NO3- concentrations. NO and N2O production by denitrification occurred under aerobic conditions and was regulated by plaque pH. Conclusions Increases of NO concentrations were in the range of effective concentrations for NO signalling to human host cells and, thus, may locally affect blood flow, signalling between nerves and inflammatory processes in the gum. This is specifically significant for the understanding of periodontal diseases, where NO has been shown to play a key role, but where gingival cells are believed to be the only source of NO. More generally, this study establishes denitrification by human-associated microbial communities as a significant metabolic pathway which, due to concurrent NO formation, provides a basis for symbiotic interactions.

  12. Brainstem Auditory Evoked Potential in HIV-Positive Adults.

    Science.gov (United States)

    Matas, Carla Gentile; Samelli, Alessandra Giannella; Angrisani, Rosanna Giaffredo; Magliaro, Fernanda Cristina Leite; Segurado, Aluísio C

    2015-10-20

    To characterize the findings of brainstem auditory evoked potential in HIV-positive individuals exposed and not exposed to antiretroviral treatment. This research was a cross-sectional, observational, and descriptive study. Forty-five HIV-positive individuals (18 not exposed and 27 exposed to the antiretroviral treatment - research groups I and II, respectively - and 30 control group individuals) were assessed through brainstem auditory evoked potential. There were no significant between-group differences regarding wave latencies. A higher percentage of altered brainstem auditory evoked potential was observed in the HIV-positive groups when compared to the control group. The most common alteration was in the low brainstem. HIV-positive individuals have a higher percentage of altered brainstem auditory evoked potential that suggests central auditory pathway impairment when compared to HIV-negative individuals. There was no significant difference between individuals exposed and not exposed to antiretroviral treatment.

  13. Clinical Approach to Supranuclear Brainstem Saccadic Gaze Palsies

    Directory of Open Access Journals (Sweden)

    Alexandra Lloyd-Smith Sequeira

    2017-08-01

    Full Text Available Failure of brainstem supranuclear centers for saccadic eye movements results in the clinical presence of a brainstem-mediated supranuclear saccadic gaze palsy (SGP, which is manifested as slowing of saccades with or without range of motion limitation of eye movements and as loss of quick phases of optokinetic nystagmus. Limitation in the range of motion of eye movements is typically worse with saccades than with smooth pursuit and is overcome with vestibular–ocular reflexive eye movements. The differential diagnosis of SGPs is broad, although acute-onset SGP is most often from brainstem infarction and chronic vertical SGP is most commonly caused by the neurodegenerative condition progressive supranuclear palsy. In this review, we discuss the brainstem anatomy and physiology of the brainstem saccade-generating network; we discuss the clinical features of SGPs, with an emphasis on insights from quantitative ocular motor recordings; and we consider the broad differential diagnosis of SGPs.

  14. Plaque control and oral hygiene methods

    LENUS (Irish Health Repository)

    Harrison, Peter

    2017-06-01

    The experimental gingivitis study of Löe et al.1 demonstrated a cause and effect relationship between plaque accumulation and gingival inflammation, and helped to establish plaque\\/biofilm as the primary risk factor for gingivitis. When healthy individuals withdrew oral hygiene efforts, gingival inflammation ensued within 21 days in all subjects. Once effective plaque removal was recommenced, clinical gingival health was quickly re-established – indicating that plaque-associated inflammation is modifiable by plaque control. As current consensus confirms that gingivitis and periodontitis may be viewed as a continuum of disease,2 the rationale for achieving effective plaque control is clear.

  15. MRI findings of multiple sclerosis involving the brainstem

    International Nuclear Information System (INIS)

    Park, Jeong Hoon; Jeong, Hae Woong; Kim, Hyun Jin; Cho, Jae Kwoeng; Kim, Chang Soo

    2001-01-01

    To describe MRI findings of multiple sclerosis involving the brainstem. Among 35 cases of clinically definite multiple sclerosis, the authors retrospectively analysed 20 in which the brainstem was involved. MR images were analysed with regard to involvement sites in the brainstem or other locations, signal intensity, multiplicity, shape, enhancement pattern, and contiguity of brainstem lesions with cisternal or ventricular CSF space. The brainstem was the only site of involvement in five cases (25%), while simultaneous involvement of the brainstem and other sites was observed in 15 cases (75%). No case involved only the midbrain or medulla oblongata, and simultaneous involvement of the midbrain, pons and medulla oblongata was noted in 12 cases (60%). The most frequently involved region of the brainstem was the medulla oblongata (n=13; 90%), followed by the pons (n=17; 85%) and the midbrain (n=16; 80%). Compared with normal white matter, brainstem lesions showed low signal intensity on T1 weighted images, and high signal intensity on T2 weighted, proton density weighted, and FLAIR images. In 17 cases (85%), multiple intensity was observed, and the shape of lesions varied: oval, round, elliptical, patchy, crescentic, confluent or amorphous were seen on axial MR images, and in 14 cases (82%), coronal or sagittal scanning showed that lesions were long and tubular. Contiguity between brainstem lesions and cisternal or ventricular CSF space was seen in all cases (100%) involving midbrain (16/16) and medulla oblongata (18/18) and in 15 of 17 (88%) involving the pons. Contrast enhancement was apparent in 7 of 12 cases (58%). In the brainstem, MRI demonstrated partial or total contiguity between lesions and cisternal or ventricular CSF space, and coronal or sagittal images showed that lesions were long and tubuler

  16. Intracranial neurenteric cyst traversing the brainstem

    Directory of Open Access Journals (Sweden)

    Jasmit Singh

    2015-01-01

    Full Text Available Neurenteric cysts (NECs, also called enterogenous cysts, are rare benign endodermal lesions of the central nervous system that probably result from separation failure of the notochord and upper gastrointestinal tract. Most frequently they are found in the lower cervical spine or the upper thoracic spine. Intracranial occurrence is rare and mostly confined to infratentorial compartment, in prepontine region [51%]. Other common locations are fourth ventricle and cerebellopontine angle. There are few reports of NEC in medulla or the cerebellum. Because of the rarity of the disease and common radiological findings, they are misinterpreted as arachnoid or simple cysts until the histopathological confirmation, unless suspected preoperatively. We herein report a rare yet interesting case of intracranial NEC traversing across the brainstem.

  17. Intraplaque hemorrhage is associated with higher structural stresses in human atherosclerotic plaques: an in vivo MRI-based 3D fluid-structure interaction study.

    Science.gov (United States)

    Huang, Xueying; Teng, Zhongzhao; Canton, Gador; Ferguson, Marina; Yuan, Chun; Tang, Dalin

    2010-12-31

    Studies using medical images have shown that intraplaque hemorrhage may accelerate plaque progression and may produce a stimulus for atherosclerosis development by increasing lipid core and plaque volume and creating new destabilizing factors. Image-based 3D computational models with fluid-structure interactions (FSI) will be used to perform plaque mechanical analysis and investigate possible associations between intraplaque hemorrhage and both plaque wall stress (PWS) and flow shear stress (FSS). In vivo MRI data of carotid plaques from 5 patients with intraplaque hemorrhage confirmed by histology were acquired. 3D multi-component FSI models were constructed for each plaque to obtain mechanical stresses. Plaque Wall Stress (PWS) and Flow Shear Stress (FSS) were extracted from all nodal points on the lumen surface of each plaque for analysis. The mean PWS value from all hemorrhage nodes of the 5 plaques combined was higher than that from non-hemorrhage nodes (75.6 versus 68.1 kPa, P = 0.0003). The mean PWS values from hemorrhage nodes for each of the 5 plaques were all significantly higher (5 out of 5) than those from non-hemorrhage nodes (P shear stress values from individual cases showed mixed results: only one out of five plaques showed mean FSS value from hemorrhage nodes was higher than that from non-hemorrhage nodes; three out of five plaques showed that their mean FSS values from hemorrhage nodes were lower than those from non-hemorrhage nodes; and one plaque showed that the difference had no statistical significance. The results of this study suggested that intraplaque hemorrhage nodes were associated with higher plaque wall stresses. Compared to flow shear stress, plaque wall stress has a better correlation with plaque component feature (hemorrhage) linked to plaque progression and vulnerability. With further validation, plaque stress analysis may provide additional stress indicators for image-based vulnerability assessment.

  18. Intraplaque hemorrhage is associated with higher structural stresses in human atherosclerotic plaques: an in vivo MRI-based 3d fluid-structure interaction study

    Directory of Open Access Journals (Sweden)

    Canton Gador

    2010-12-01

    Full Text Available Abstract Background Studies using medical images have shown that intraplaque hemorrhage may accelerate plaque progression and may produce a stimulus for atherosclerosis development by increasing lipid core and plaque volume and creating new destabilizing factors. Image-based 3D computational models with fluid-structure interactions (FSI will be used to perform plaque mechanical analysis and investigate possible associations between intraplaque hemorrhage and both plaque wall stress (PWS and flow shear stress (FSS. Methods In vivo MRI data of carotid plaques from 5 patients with intraplaque hemorrhage confirmed by histology were acquired. 3D multi-component FSI models were constructed for each plaque to obtain mechanical stresses. Plaque Wall Stress (PWS and Flow Shear Stress (FSS were extracted from all nodal points on the lumen surface of each plaque for analysis. Results The mean PWS value from all hemorrhage nodes of the 5 plaques combined was higher than that from non-hemorrhage nodes (75.6 versus 68.1 kPa, P = 0.0003. The mean PWS values from hemorrhage nodes for each of the 5 plaques were all significantly higher (5 out of 5 than those from non-hemorrhage nodes (P 2, P = 0.0002. However, the mean flow shear stress values from individual cases showed mixed results: only one out of five plaques showed mean FSS value from hemorrhage nodes was higher than that from non-hemorrhage nodes; three out of five plaques showed that their mean FSS values from hemorrhage nodes were lower than those from non-hemorrhage nodes; and one plaque showed that the difference had no statistical significance. Conclusion The results of this study suggested that intraplaque hemorrhage nodes were associated with higher plaque wall stresses. Compared to flow shear stress, plaque wall stress has a better correlation with plaque component feature (hemorrhage linked to plaque progression and vulnerability. With further validation, plaque stress analysis may provide

  19. Mechanical Stresses in Carotid Plaques

    DEFF Research Database (Denmark)

    Samuel, Samuel Alberg

    simulationer, som tillod beregning af longitudinelle stress-niveauer i den fibrøse kappe. Afhandlingen indeholder tre artikler, som beskriver denne metode. Den første; “Mechanical Stresses in Carotid Plaques using MRI-Based Fluid Structure Interaction Models”, beskriver i detaljer metoden til at danne de...

  20. Contemporary perspective on plaque control.

    Science.gov (United States)

    Marsh, P D

    2012-06-22

    The aim of this review article is to provide a scientific platform that will enable the dental team to develop a rational approach to plaque control based on the latest knowledge of the role of the oral microflora in health and disease. The resident oral microflora is natural and forms spatially-organised, interactive, multi-species biofilms on mucosal and dental surfaces in the mouth. These resident oral microbial communities play a key function in the normal development of the physiology of the host and are important in preventing colonisation by exogenous and often undesirable microbes. A dynamic balance exists between the resident microflora and the host in health, and disease results from a breakdown of this delicate relationship. Patients should be taught effective plaque control techniques that maintain dental biofilms at levels compatible with oral health so as to retain the beneficial properties of the resident microflora while reducing the risk of dental disease from excessive plaque accumulation. Antimicrobial and antiplaque agents in oral care products can augment mechanical plaque control by several direct and indirect mechanisms that not only involve reducing or removing dental biofilms but also include inhibiting bacterial metabolism when the agents are still present at sub-lethal concentrations.

  1. A brainstem variant of reversible posterior leukoencephalopathy syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Kitaguchi, H.; Tomimoto, H.; Terada, K. [Kyoto University, Department of Neurology, Graduate School of Medicine, Sakyo-ku, Kyoto (Japan); Miki, Y.; Yamamoto, A. [Kyoto University, Department of Nuclear Medicine and Diagnostic Imaging, Graduate School of Medicine, Sakyo-ku, Kyoto (Japan); Satoi, H.; Kanda, M. [Ijinkai Takeda General Hospital, Department of Neurology, Fushimi-ku, Kyoto (Japan); Fukuyama, H. [Kyoto University, Human Brain Research Center, Graduate School of Medicine, Sakyo-ku, Kyoto (Japan)

    2005-09-01

    Reversible posterior leukoencephalopathy syndrome (RPLS) is caused by various heterogeneous factors, the commonest being hypertension, followed by nonhypertensive causes such as eclampsia, renal diseases and immunosuppressive therapy. Patients with RPLS exhibit bilateral white and gray matter abnormalities in the posterior aspects of the cerebral hemispheres. However, this syndrome may affect the brainstem predominantly, and these cases are designated as hypertensive brainstem encephalopathy. We present here two patients with reversible brainstem encephalopathy: one with hypertension and the other without hypertension. These patients presented with swelling and diffuse hyperintensities of the brainstem in fluid-attenuated inversion-recovery (FLAIR) and T2-weighted MRI, but with relatively mild clinical symptoms. They recovered without major neurological deficits, but had residual lacunar lesions in the pons. Reversible brainstem encephalopathy with characteristic MRI features was found in both hypertensive and nonhypertensive patients. These patients were diagnosed with a brainstem variant of RPLS, which is potentially fully reversible after an adequate treatment, and therefore should be carefully differentiated from other brainstem disease conditions. (orig.)

  2. A brainstem variant of reversible posterior leukoencephalopathy syndrome

    International Nuclear Information System (INIS)

    Kitaguchi, H.; Tomimoto, H.; Terada, K.; Miki, Y.; Yamamoto, A.; Satoi, H.; Kanda, M.; Fukuyama, H.

    2005-01-01

    Reversible posterior leukoencephalopathy syndrome (RPLS) is caused by various heterogeneous factors, the commonest being hypertension, followed by nonhypertensive causes such as eclampsia, renal diseases and immunosuppressive therapy. Patients with RPLS exhibit bilateral white and gray matter abnormalities in the posterior aspects of the cerebral hemispheres. However, this syndrome may affect the brainstem predominantly, and these cases are designated as hypertensive brainstem encephalopathy. We present here two patients with reversible brainstem encephalopathy: one with hypertension and the other without hypertension. These patients presented with swelling and diffuse hyperintensities of the brainstem in fluid-attenuated inversion-recovery (FLAIR) and T2-weighted MRI, but with relatively mild clinical symptoms. They recovered without major neurological deficits, but had residual lacunar lesions in the pons. Reversible brainstem encephalopathy with characteristic MRI features was found in both hypertensive and nonhypertensive patients. These patients were diagnosed with a brainstem variant of RPLS, which is potentially fully reversible after an adequate treatment, and therefore should be carefully differentiated from other brainstem disease conditions. (orig.)

  3. Animal models to study plaque vulnerability

    NARCIS (Netherlands)

    Schapira, K.; Heeneman, S.; Daemen, M. J. A. P.

    2007-01-01

    The need to identify and characterize vulnerable atherosclerotic lesions in humans has lead to the development of various animal models of plaque vulnerability. In this review, current concepts of the vulnerable plaque as it leads to an acute coronary event are described, such as plaque rupture,

  4. Current diagnostic modalities for vulnerable plaque detection

    NARCIS (Netherlands)

    J.A. Schaar (Johannes); F. Mastik (Frits); E.S. Regar (Eveline); C.A. den Uil (Corstiaan); F.J.H. Gijsen (Frank); J.J. Wentzel (Jolanda); P.W.J.C. Serruys (Patrick); A.F.W. van der Steen (Ton)

    2007-01-01

    textabstractRupture of vulnerable plaques is the main cause of acute coronary syndrome and myocardial infarction. Identification of vulnerable plaques is therefore essential to enable the development of treatment modalities to stabilize such plaques. Several diagnostic methods are currently tested

  5. Arterial territories of human brain: brainstem and cerebellum

    International Nuclear Information System (INIS)

    Tatu, L.; Moulin, T.; Bogousslavsky, J.; Duvernoy, H.

    1997-01-01

    The development of neuroimaging has allowed clinicians to improve clinico-anatomic correlations in patients with strokes. Brainstem and cerebellum structures are well delineated on MRI, but there is a lack of standardization in their arterial supply. We present a system of 12 brainstem and cerebellum axial sections, depicting the dominant arterial territories and the most important anatomic structures. These sections may be used as a practical tool to determine arterial territories on MRI, and may help establish consistent clinico-anatomic correlations in patients with brainstem and cerebellar ischemic strokes. (authors)

  6. Enterovirus 71 Brainstem Encephalitis and Cognitive and Motor Deficits

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2006-12-01

    Full Text Available Follow-up studies were conducted in 63 previously healthy children with enterovirus 71 brainstem encephalitis (49 stage II, 7 stage Ilia, and 7 stage Illb at National Cheng Kung University Hospital, Tainan, Taiwan.

  7. Brainstem and cerebellar changes after cerebrovascular accidents: magnetic resonance imaging

    International Nuclear Information System (INIS)

    Uchino, A.; Takase, Y.; Nomiyama, K.; Egashira, R.; Kudo, S.

    2006-01-01

    We illustrate the various types of secondary degeneration in the brainstem and/or cerebellum detected on magnetic resonance (MR) images obtained after cerebrovascular accidents. The changes include: (a) ipsilateral nigral degeneration after striatal infarction; (b) Wallerian degeneration of the pyramidal tract in the brainstem after supratentorial pyramidal tract or motor cortex injury; (c) Wallerian degeneration of the corticopontine tract in the brainstem after frontal lobe infarction; (d) ipsilateral brainstem atrophy and crossed cerebellar atrophy due to an extensive supratentorial lesion; (e) ipsilateral superior cerebellar peduncle atrophy, contralateral rubral degeneration, contralateral inferior olivary degeneration and ipsilateral cerebellar atrophy after dentate nucleus hemorrhage; (f) ipsilateral inferior olivary degeneration after pontine tegmentum hemorrhage; (g) bilateral wallerian degeneration of the pontocerebellar tracts after ventromedial pontine infarction or basis pontis hemorrhage; and (h) ipsilateral cerebellar atrophy after middle cerebellar peduncle hemorrhage. (orig.)

  8. Brainstem and cerebellar changes after cerebrovascular accidents: magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uchino, A.; Takase, Y.; Nomiyama, K.; Egashira, R.; Kudo, S. [Saga Medical School, Department of Radiology, Saga (Japan)

    2006-03-15

    We illustrate the various types of secondary degeneration in the brainstem and/or cerebellum detected on magnetic resonance (MR) images obtained after cerebrovascular accidents. The changes include: (a) ipsilateral nigral degeneration after striatal infarction; (b) Wallerian degeneration of the pyramidal tract in the brainstem after supratentorial pyramidal tract or motor cortex injury; (c) Wallerian degeneration of the corticopontine tract in the brainstem after frontal lobe infarction; (d) ipsilateral brainstem atrophy and crossed cerebellar atrophy due to an extensive supratentorial lesion; (e) ipsilateral superior cerebellar peduncle atrophy, contralateral rubral degeneration, contralateral inferior olivary degeneration and ipsilateral cerebellar atrophy after dentate nucleus hemorrhage; (f) ipsilateral inferior olivary degeneration after pontine tegmentum hemorrhage; (g) bilateral wallerian degeneration of the pontocerebellar tracts after ventromedial pontine infarction or basis pontis hemorrhage; and (h) ipsilateral cerebellar atrophy after middle cerebellar peduncle hemorrhage. (orig.)

  9. Challenge-driven attention: interacting frontal and brainstem systems

    Directory of Open Access Journals (Sweden)

    Rajeev D S Raizada

    2008-03-01

    Full Text Available The world is an unpredictable place, presenting challenges that fl uctuate from moment to moment. However, the neural systems for responding to such challenges are far from fully understood. Using fMRI, we studied an audiovisual task in which the trials' diffi culty and onset times varied unpredictably. Two regions were found to increase their activation for challenging trials, with their activities strongly correlated: right frontal cortex and the brainstem. The frontal area matched regions found in previous human studies of cognitive control, and activated in a graded manner with increasing task diffi culty. The brainstem responded only to the most diffi cult trials, showing a phasic activity pattern paralleling locus coeruleus recordings in monkeys. These results reveal a bridge between animal and human studies, and suggest interacting roles for the brainstem and right frontal cortex: the brainstem may signal that an attentional challenge is occurring, while right frontal cortex allocates cognitive resources in response.

  10. Plaque disruption by coronary computed tomographic angiography in stable patients vs. acute coronary syndrome: a feasibility study.

    Science.gov (United States)

    Bilolikar, Abhay N; Goldstein, James A; Madder, Ryan D; Chinnaiyan, Kavitha M

    2016-03-01

    This study was designed to determine whether coronary CT angiography (CTA) can detect features of plaque disruption in clinically stable patients and to compare lesion prevalence and features between stable patients and those with acute coronary syndrome (ACS). We retrospectively identified patients undergoing CTA, followed by invasive coronary angiography (ICA) within 60 days. Quantitative 3-vessel CTA lesion analysis was performed on all plaques ≥25% stenosis to assess total plaque volume, low attenuation plaque (LAP, disruption, including ulceration and intra-plaque dye penetration (IDP). ICA was employed as a reference standard for disruption. A total of 145 (94 ACS and 51 stable) patients were identified. By CTA, plaque disruption was evident in 77.7% of ACS cases. Although more common among those with ACS, CTA also detected plaque disruption in 37.3% of clinically stable patients (P disruption as determined by CTA. Though the prevalence of plaque disruption is less than patients with ACS, these findings support the concept that some clinically stable patients may harbour 'silent' disrupted plaques. These findings may have implications for detection of 'at risk' plaques and patients. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  11. Bacterial sex in dental plaque.

    Science.gov (United States)

    Olsen, Ingar; Tribble, Gena D; Fiehn, Nils-Erik; Wang, Bing-Yan

    2013-01-01

    Genes are transferred between bacteria in dental plaque by transduction, conjugation, and transformation. Membrane vesicles can also provide a mechanism for horizontal gene transfer. DNA transfer is considered bacterial sex, but the transfer is not parallel to processes that we associate with sex in higher organisms. Several examples of bacterial gene transfer in the oral cavity are given in this review. How frequently this occurs in dental plaque is not clear, but evidence suggests that it affects a number of the major genera present. It has been estimated that new sequences in genomes established through horizontal gene transfer can constitute up to 30% of bacterial genomes. Gene transfer can be both inter- and intrageneric, and it can also affect transient organisms. The transferred DNA can be integrated or recombined in the recipient's chromosome or remain as an extrachromosomal inheritable element. This can make dental plaque a reservoir for antimicrobial resistance genes. The ability to transfer DNA is important for bacteria, making them better adapted to the harsh environment of the human mouth, and promoting their survival, virulence, and pathogenicity.

  12. Bacterial sex in dental plaque

    Directory of Open Access Journals (Sweden)

    Ingar Olsen

    2013-06-01

    Full Text Available Genes are transferred between bacteria in dental plaque by transduction, conjugation, and transformation. Membrane vesicles can also provide a mechanism for horizontal gene transfer. DNA transfer is considered bacterial sex, but the transfer is not parallel to processes that we associate with sex in higher organisms. Several examples of bacterial gene transfer in the oral cavity are given in this review. How frequently this occurs in dental plaque is not clear, but evidence suggests that it affects a number of the major genera present. It has been estimated that new sequences in genomes established through horizontal gene transfer can constitute up to 30% of bacterial genomes. Gene transfer can be both inter- and intrageneric, and it can also affect transient organisms. The transferred DNA can be integrated or recombined in the recipient's chromosome or remain as an extrachromosomal inheritable element. This can make dental plaque a reservoir for antimicrobial resistance genes. The ability to transfer DNA is important for bacteria, making them better adapted to the harsh environment of the human mouth, and promoting their survival, virulence, and pathogenicity.

  13. Study of the correlation of brainstem auditory evoked potentials and magnetic resonance imaging in children with spastic cerebral palsy

    International Nuclear Information System (INIS)

    Fobe, Lisete Pessoa de Oliveira

    1999-01-01

    Central auditory evaluation in 21 children with cerebral palsy was done with brainstem auditory evoked potentials (BAEP) and correlated with brain magnetic resonance imaging findings (MRI); 12 boys and 9 girls between 5 and 12 years old were studied. All children had follow-up at the Institute of Orthopedics and Traumatology of Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo. The control group was done with 17 children, 10 boys and 7 girls (mean age 8.06 years, SD 2.27 years). The BAEP abnormalities were: decrease of latency of wave V; decrease of latency III-V and I-IV intervals at the right side. All patients has MRI supratentorial abnormalities and 11 had brainstem atrophy. The MRI pathologic findings were: ventricular enlargement (n=17 or 80.95%), cortical/subcortical atrophy (n=15 or 71.42%), left brainstem atrophy (n=11 or 52.38%), periventricular leukomalacia (n=10 or 47.61%), infarction in the left middle cerebral artery territory (n=6 or 28.57%), and malformations such as schizencephaly and colpocephaly (n=5 or 23.80%). The findings of the decrease latencies in children with cerebral palsy suggest the contribution of decussating auditory fibers at the lower and upper pons and midbrain, the lack of homogeneity of the surrounding volume of the conductor fibres and the presence of several concurrently active potential generators sources, should be facilitating mechanisms for the nervous input to brainstem. (author)

  14. Study of the correlation of brainstem auditory evoked potentials and magnetic resonance imaging in children with spastic cerebral palsy

    Energy Technology Data Exchange (ETDEWEB)

    Fobe, Lisete Pessoa de Oliveira [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina]. E-mail: lispessoa@yahoo.com

    1999-12-01

    Central auditory evaluation in 21 children with cerebral palsy was done with brainstem auditory evoked potentials (BAEP) and correlated with brain magnetic resonance imaging findings (MRI); 12 boys and 9 girls between 5 and 12 years old were studied. All children had follow-up at the Institute of Orthopedics and Traumatology of Hospital das Clinicas da Faculdade de Medicina da Universidade de Sao Paulo. The control group was done with 17 children, 10 boys and 7 girls (mean age 8.06 years, SD 2.27 years). The BAEP abnormalities were: decrease of latency of wave V; decrease of latency III-V and I-IV intervals at the right side. All patients has MRI supratentorial abnormalities and 11 had brainstem atrophy. The MRI pathologic findings were: ventricular enlargement (n=17 or 80.95%), cortical/subcortical atrophy (n=15 or 71.42%), left brainstem atrophy (n=11 or 52.38%), periventricular leukomalacia (n=10 or 47.61%), infarction in the left middle cerebral artery territory (n=6 or 28.57%), and malformations such as schizencephaly and colpocephaly (n=5 or 23.80%). The findings of the decrease latencies in children with cerebral palsy suggest the contribution of decussating auditory fibers at the lower and upper pons and midbrain, the lack of homogeneity of the surrounding volume of the conductor fibres and the presence of several concurrently active potential generators sources, should be facilitating mechanisms for the nervous input to brainstem. (author)

  15. Denture plaque--past and recent concerns.

    Science.gov (United States)

    Nikawa, H; Hamada, T; Yamamoto, T

    1998-05-01

    This paper critically reviews the history of denture plaque and identifies some concerns with the presence of Candida in the mouth. This review covers literature sources related to Candida albicans and its relationship to denture plaque. The articles selected for this review are from referred journals and describe C. albicans and its relationship to oral, gastrointestinal and pleuropulmonary infections. The relationship to caries, root caries and periodontal disease is also covered. Denture plaque containing Candida could cause not only oral candidiasis, like oral thrush or denture-induced stomatitis, but also caries, root caries and periodontitis of abutment teeth. However, there is only limited experimental evidence or information available on the cariogenicity of Candida. The continuous swallowing or aspiration of micro-organisms from denture plaque exposes patients, particularly the immunocompromised host or medicated elderly, to the risks of unexpected infections. The term, 'denture plaque' has been used throughout the review. However, the term 'plaque on denture' should be used because the microbial flora and its pathogenicity of denture plaque resembles those of plaque formed on the tooth surface, so called dental plaque. In addition, the term 'denture related stomatitis' would be preferable to 'denture induced stomatitis', since the inflammation of (palatal) mucosa is not induced by the denture, but by wearing the denture or by plaque on the denture.

  16. Noninvasive characterization of carotid plaque strain.

    Science.gov (United States)

    Khan, Amir A; Sikdar, Siddhartha; Hatsukami, Thomas; Cebral, Juan; Jones, Michael; Huston, John; Howard, George; Lal, Brajesh K

    2017-06-01

    Current risk stratification of internal carotid artery plaques based on diameter-reducing percentage stenosis may be unreliable because ischemic stroke results from plaque disruption with atheroembolization. Biomechanical forces acting on the plaque may render it vulnerable to rupture. The feasibility of ultrasound-based quantification of plaque displacement and strain induced by hemodynamic forces and their relationship to high-risk plaques have not been determined. We studied the feasibility and reliability of carotid plaque strain measurement from clinical B-mode ultrasound images and the relationship of strain to high-risk plaque morphology. We analyzed carotid ultrasound B-mode cine loops obtained in patients with asymptomatic ≥50% stenosis during routine clinical scanning. Optical flow methods were used to quantify plaque motion and shear strain during the cardiac cycle. The magnitude (maximum absolute shear strain rate [MASSR]) and variability (entropy of shear strain rate [ESSR] and variance of shear strain rate [VSSR]) of strain were combined into a composite shear strain index (SSI), which was assessed for interscan repeatability and correlated with plaque echolucency. Nineteen patients (mean age, 70 years) constituting 36 plaques underwent imaging; 37% of patients (n = 7) showed high strain (SSI ≥0.5; MASSR, 2.2; ESSR, 39.7; VSSR, 0.03) in their plaques; the remaining clustered into a low-strain group (SSI routine B-mode imaging using clinical ultrasound machines. High plaque strain correlates with known high-risk echolucent morphology. Strain measurement can complement identification of patients at high risk for plaque disruption and stroke. Copyright © 2017 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  17. MR plaque imaging of the carotid artery

    International Nuclear Information System (INIS)

    Watanabe, Yuji; Nagayama, Masako

    2010-01-01

    Atherosclerotic carotid plaque represents a major cause of cerebral ischemia. The detection of vulnerable plaque is important for preventing future cardiovascular events. The key factors in advanced plaque that are most likely to lead to patient complications are the condition of the fibrous cap, the size of the necrotic core and hemorrhage, and the extent of inflammatory activity within the plaque. Magnetic resonance (MR) imaging has excellent soft tissue contrast and can allow for a more accurate and objective estimation of carotid wall morphology and plaque composition. Recent advances in MR imaging techniques have permitted serial monitoring of atherosclerotic disease evolution and the identification of intraplaque risk factors for accelerated progression. The purpose of this review article is to review the current state of techniques of carotid wall MR imaging and the characterization of plaque components and surface morphology with MR imaging, and to describe the clinical practice of carotid wall MR imaging for the determination of treatment plan. (orig.)

  18. CT coronary angiography: impact of adapted statistical iterative reconstruction (ASIR) on coronary stenosis and plaque composition analysis.

    Science.gov (United States)

    Fuchs, Tobias A; Fiechter, Michael; Gebhard, Cathérine; Stehli, Julia; Ghadri, Jelena R; Kazakauskaite, Egle; Herzog, Bernhard A; Husmann, Lars; Gaemperli, Oliver; Kaufmann, Philipp A

    2013-03-01

    To assess the impact of adaptive statistical iterative reconstruction (ASIR) on coronary plaque volume and composition analysis as well as on stenosis quantification in high definition coronary computed tomography angiography (CCTA). We included 50 plaques in 29 consecutive patients who were referred for the assessment of known or suspected coronary artery disease (CAD) with contrast-enhanced CCTA on a 64-slice high definition CT scanner (Discovery HD 750, GE Healthcare). CCTA scans were reconstructed with standard filtered back projection (FBP) with no ASIR (0 %) or with increasing contributions of ASIR, i.e. 20, 40, 60, 80 and 100 % (no FBP). Plaque analysis (volume, components and stenosis degree) was performed using a previously validated automated software. Mean values for minimal diameter and minimal area as well as degree of stenosis did not change significantly using different ASIR reconstructions. There was virtually no impact of reconstruction algorithms on mean plaque volume or plaque composition (e.g. soft, intermediate and calcified component). However, with increasing ASIR contribution, the percentage of plaque volume component between 401 and 500 HU decreased significantly (p ASIR, which has been developed for noise reduction in latest high resolution CCTA scans, can be used reliably without interfering with the plaque analysis and stenosis severity assessment.

  19. Effect of calcification on the mechanical stability of plaque based on a three-dimensional carotid bifurcation model

    Science.gov (United States)

    2012-01-01

    Background This study characterizes the distribution and components of plaque structure by presenting a three-dimensional blood-vessel modelling with the aim of determining mechanical properties due to the effect of lipid core and calcification within a plaque. Numerical simulation has been used to answer how cap thickness and calcium distribution in lipids influence the biomechanical stress on the plaque. Method Modelling atherosclerotic plaque based on structural analysis confirms the rationale for plaque mechanical examination and the feasibility of our simulation model. Meaningful validation of predictions from modelled atherosclerotic plaque model typically requires examination of bona fide atherosclerotic lesions. To analyze a more accurate plaque rupture, fluid-structure interaction is applied to three-dimensional blood-vessel carotid bifurcation modelling. A patient-specific pressure variation is applied onto the plaque to influence its vulnerability. Results Modelling of the human atherosclerotic artery with varying degrees of lipid core elasticity, fibrous cap thickness and calcification gap, which is defined as the distance between the fibrous cap and calcification agglomerate, form the basis of our rupture analysis. Finite element analysis shows that the calcification gap should be conservatively smaller than its threshold to maintain plaque stability. The results add new mechanistic insights and methodologically sound data to investigate plaque rupture mechanics. Conclusion Structural analysis using a three-dimensional calcified model represents a more realistic simulation of late-stage atherosclerotic plaque. We also demonstrate that increases of calcium content that is coupled with a decrease in lipid core volume can stabilize plaque structurally. PMID:22336469

  20. Effect of calcification on the mechanical stability of plaque based on a three-dimensional carotid bifurcation model

    Directory of Open Access Journals (Sweden)

    Wong Kelvin KL

    2012-02-01

    Full Text Available Abstract Background This study characterizes the distribution and components of plaque structure by presenting a three-dimensional blood-vessel modelling with the aim of determining mechanical properties due to the effect of lipid core and calcification within a plaque. Numerical simulation has been used to answer how cap thickness and calcium distribution in lipids influence the biomechanical stress on the plaque. Method Modelling atherosclerotic plaque based on structural analysis confirms the rationale for plaque mechanical examination and the feasibility of our simulation model. Meaningful validation of predictions from modelled atherosclerotic plaque model typically requires examination of bona fide atherosclerotic lesions. To analyze a more accurate plaque rupture, fluid-structure interaction is applied to three-dimensional blood-vessel carotid bifurcation modelling. A patient-specific pressure variation is applied onto the plaque to influence its vulnerability. Results Modelling of the human atherosclerotic artery with varying degrees of lipid core elasticity, fibrous cap thickness and calcification gap, which is defined as the distance between the fibrous cap and calcification agglomerate, form the basis of our rupture analysis. Finite element analysis shows that the calcification gap should be conservatively smaller than its threshold to maintain plaque stability. The results add new mechanistic insights and methodologically sound data to investigate plaque rupture mechanics. Conclusion Structural analysis using a three-dimensional calcified model represents a more realistic simulation of late-stage atherosclerotic plaque. We also demonstrate that increases of calcium content that is coupled with a decrease in lipid core volume can stabilize plaque structurally.

  1. Vestibular myogenic and acoustical brainstem evoked potentials in neurological practice

    Directory of Open Access Journals (Sweden)

    O. S. Korepina

    2012-01-01

    Full Text Available Along with the inspection of acoustical cortex and brainstem EP in neurologic, otoneurologic and audiologic practice recently start to use so-called vestibular evoked myogenic potentials (VEMP. It is shown, that at ear stimulation by a loud sound and record of sterno-cleidomastoid contraction is possible to estimate function of the inferior vestibular nerve and vestibulospinal pathways, a sacculo-cervical reflex. In article some methodical and clinical questions of application of these kinds are presented. Combine research acoustic brainstem EP and VEMP allows to confirm effectively lesions of acoustical and vestibular ways at brainstem. The conclusion becomes, that this kind of inspection is important for revealing demielinisation and defeats in vestibulospinal tract, that quite often happens at MS, and at estimation of efficiency of treatment

  2. Magnetic resonance imaging in brain-stem tumors

    International Nuclear Information System (INIS)

    Nomura, Mikio; Saito, Hisazumi; Akino, Minoru; Abe, Hiroshi.

    1988-01-01

    Four patients with brain-stem tumors underwent magnetic resonance imaging (MRI) before and after radiotherapy. The brain-stem tumors were seen as a low signal intensity on T1-weighted images and as a high signal intensity on T2-weighted images. A tumor and its anatomic involvement were more clearly visualized on MRI than on cuncurrently performed CT. Changes in tumor before and after radiotherapy could be determined by measuring the diameter of tumor on sagittal and coronal images. This allowed quantitative evaluation of the reduction of tumor in association with improvement of symptoms. The mean T1 value in the central part of tumors was shortened in all patients after radiotherapy. The results indicate that MRI may assist in determining the effect of radiotherapy for brain-stem tumors. (Namekawa, K)

  3. Clinical and radiological features of hypertensive brainstem encephalopathy

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    Xiao-qiu LI

    2015-07-01

    Full Text Available Objective To discuss the diagnosis and treatment of hypertensive brainstem encephalopathy. Methods  The clinical and imaging data of 3 cases of hypertensive brainstem encephalopathy were summarized and analyzed for the purpose of improving the acumen in diagnosis and treatment. Results All the 3 patients showed relatively mild clinical symptoms, and they were misdiagnosed in different degrees during the treatment, but their clinical symptoms were improved by rapid and effective antihypertensive therapy. Cerebral CT and MRI scans revealed extensive abnormal signals in brain stem, with or without supratentorial lesions and brain stem hemorrhage. The lesions as revealed by imaging were improved significantly after treatment. Conclusions Clinical-radiographic dissociation is the classic feature of hypertensive brainstem encephalopathy. The clinical symptoms and lesions as shown by imaging could be improved after active treatment. DOI: 10.11855/j.issn.0577-7402.2015.06.03

  4. Current status of vulnerable plaque detection.

    LENUS (Irish Health Repository)

    Sharif, Faisal

    2012-02-01

    Critical coronary stenoses have been shown to contribute to only a minority of acute coronary syndromes (ACS) and sudden cardiac death. Autopsy studies have identified a subgroup of high-risk patients with disrupted vulnerable plaque and modest stenosis. Consequently, a clinical need exists to develop methods to identify these plaques prospectively before disruption and clinical expression of disease. Recent advances in invasive and noninvasive imaging techniques have shown the potential to identify these high-risk plaques. The anatomical characteristics of the vulnerable plaque such as thin cap fibroatheroma and lipid pool can be identified with angioscopy, high frequency intravascular ultrasound, intravascular MRI, and optical coherence tomography. Efforts have also been made to recognize active inflammation in high-risk plaques using intravascular thermography. Plaque chemical composition by measuring electromagnetic radiation using spectroscopy is also an emerging technology to detect vulnerable plaques. Noninvasive imaging with MRI, CT, and PET also holds the potential to differentiate between low and high-risk plaques. However, at present none of these imaging modalities are able to detect vulnerable plaque neither has been shown to definitively predict outcome. Nevertheless in contrast, there has been a parallel development in the physiological assessment of advanced atherosclerotic coronary artery disease. Thus recent trials using fractional flow reserve in patients with modest non flow-limiting stenoses have shown that deferral of PCI with optimal medical therapy in these patients is superior to coronary intervention. Further trials are needed to provide more information regarding the natural history of high-risk but non flow-limiting plaque to establish patient-specific targeted therapy and to refine plaque stabilizing strategies in the future.

  5. The Influence of Various Morphologic and Hemodynamic Carotid Plaque Characteristics on Neurological Events Onset and Deaths

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    Milan D. Brajovic

    2009-01-01

    Full Text Available A group of 72 patients with 111 asymptomatic carotid stenoses (ACS, mean age 65.42 ± 9.21, and a group of 36 patients with 58 symptomatic carotid stenoses (SCS, mean age 67.63 ± 8.79, were analyzed prospectively during a 3-year follow-up period. All patients underwent color duplex scan sonography (CDS, carotid arteriography, computed tomography (CT scan, and neurological examination. The aim of the study was to analyze the correlation between echo plaque morphology (degree and plaque quality, local hemodynamic plaque characteristics, ischemic CT findings, and onset of new neurological events and deaths. The results analysis showed significantly more ACS in the group of 30–49% stenosis (p < 0.001, but significantly more SCS in the group of 70–89% (p < 0.0001 and ≥90% stenosis (p < 0.05. Fibrous plaque was more frequent in the ACS group (p < 0.001, while ulcerated and mixed plaques were more frequent in the SCS group (both p < 0.0001. In the SCS group, a significantly higher frequency of increased peak systolic and end diastolic velocities was noted at the beginning and end of the study (both p < 0.01, as well as for contralateral common (CCA or internal carotid artery (ICA occlusion (p < 0.05 and p < 0.01, respectively, but reduced carotid blood flow volume (p < 0.05 only at the end of the study. In the ACS group, the best correlation with new neurological events and deaths was shown with positive CT findings, peak systolic flow velocity over 210 cm/sec, end diastolic flow velocity over 110 cm/sec, plaque stenosis ≥70%, plaque ulceration, mixed plaque (all p < 0.0001; stenosis ≥50% (p < 0.001; and reduced carotid blood flow volume (p < 0.05.

  6. Supervised machine learning-based classification scheme to segment the brainstem on MRI in multicenter brain tumor treatment context.

    Science.gov (United States)

    Dolz, Jose; Laprie, Anne; Ken, Soléakhéna; Leroy, Henri-Arthur; Reyns, Nicolas; Massoptier, Laurent; Vermandel, Maximilien

    2016-01-01

    To constrain the risk of severe toxicity in radiotherapy and radiosurgery, precise volume delineation of organs at risk is required. This task is still manually performed, which is time-consuming and prone to observer variability. To address these issues, and as alternative to atlas-based segmentation methods, machine learning techniques, such as support vector machines (SVM), have been recently presented to segment subcortical structures on magnetic resonance images (MRI). SVM is proposed to segment the brainstem on MRI in multicenter brain cancer context. A dataset composed by 14 adult brain MRI scans is used to evaluate its performance. In addition to spatial and probabilistic information, five different image intensity values (IIVs) configurations are evaluated as features to train the SVM classifier. Segmentation accuracy is evaluated by computing the Dice similarity coefficient (DSC), absolute volumes difference (AVD) and percentage volume difference between automatic and manual contours. Mean DSC for all proposed IIVs configurations ranged from 0.89 to 0.90. Mean AVD values were below 1.5 cm(3), where the value for best performing IIVs configuration was 0.85 cm(3), representing an absolute mean difference of 3.99% with respect to the manual segmented volumes. Results suggest consistent volume estimation and high spatial similarity with respect to expert delineations. The proposed approach outperformed presented methods to segment the brainstem, not only in volume similarity metrics, but also in segmentation time. Preliminary results showed that the approach might be promising for adoption in clinical use.

  7. Sensitization of trigeminal brainstem pathways in a model for tear deficient dry eye.

    Science.gov (United States)

    Rahman, Mostafeezur; Okamoto, Keiichiro; Thompson, Randall; Katagiri, Ayano; Bereiter, David A

    2015-05-01

    Chronic dry eye disease (DE) is associated with an unstable tear film and symptoms of ocular discomfort. The characteristics of symptoms suggest a key role for central neural processing; however, little is known about central neuroplasticity and DE. We used a model for tear deficient DE and assessed effects on eye blink behavior, orbicularis oculi muscle activity (OOemg), and trigeminal brainstem neural activity in male rats. Ocular-responsive neurons were recorded at the interpolaris/caudalis transition (Vi/Vc) and Vc/upper cervical cord (Vc/C1) regions under isoflurane, whereas OOemg activity was recorded under urethane. Spontaneous tear volume was reduced by ∼50% at 14 days after exorbital gland removal. Hypertonic saline-evoked eye blink behavior in awake rats was enhanced throughout the 14 days after surgery. Saline-evoked neural activity at the Vi/Vc transition and in superficial and deep laminae at the Vc/C1 region was greatly enhanced in DE rats. Neurons from DE rats classified as wide dynamic range displayed enlarged convergent periorbital receptive fields consistent with central sensitization. Saline-evoked OOemg activity was markedly enhanced in DE rats compared with controls. Synaptic blockade at the Vi/Vc transition or the Vc/C1 region greatly reduced hypertonic saline-evoked OOemg activity in DE and sham rats. These results indicated that persistent tear deficiency caused sensitization of ocular-responsive neurons at multiple regions of the caudal trigeminal brainstem and enhanced OOemg activity. Central sensitization of ocular-related brainstem circuits is a significant factor in DE and likely contributes to the apparent weak correlation between peripheral signs of tear dysfunction and symptoms of irritation.

  8. PLAQUE ASSAY OF NEWCASTLE DISEASE VIRUS

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    B. Sardjono

    2012-09-01

    Full Text Available The Newcastle disease virus (NDV was isolated from a 3 months-old indigenous chicken (buras or kampung chicken which showed clinical signs of Newcastle disease (ND. For viral isolation a small part of the spleen and lung were inoculated into 10 days-old embryonated chicken eggs. The physical characteristics of the isolate (A/120 were studied. The hemagglutination of chicken red blood cell showed slow elution, thermostability of hemagglutinin at 56°C was 120 minutes. The vims was able to agglutinate horse erythrocytes but not those of sheep. The biological characteristics on mean death time (MDT of embryonated chicken egg and plaque morphology on chicken embryo fibroblast (CEF primary cell cultures were studied. The MDT was 56 hours, the isolate was velogenic NDV. There were three different plaque morphologies on CEF : 2 mm clear plaques, 1 mm clear plaques, and minute clear plaques which were visible only with microscopic examination.

  9. Quantification of arterial plaque and lumen density with MDCT

    International Nuclear Information System (INIS)

    Paul, Narinder S.; Blobel, Joerg; Kashani, Hany; Rice, Murray; Ursani, Ali

    2010-01-01

    Purpose: This study aimed to derive a mathematical correction function in order to normalize the CT number measurements for small volume arterial plaque and small vessel mimicking objects, imaged with multidetector CT (MDCT). Methods: A commercially available calcium plaque phantom (QRM GmbH, Moehrendorf, Germany) and a custom built cardiovascular phantom were scanned with 320 and 64 MDCT scanners. The calcium hydroxyapatite plaque phantom contained objects 0.5-5.0 mm in diameter with known CT attenuation nominal values ranging 50-800 HU. The cardiovascular phantom contained vessel mimicking objects 1.0-5.0 mm in diameter with different contrast media. Both phantoms were scanned using clinical protocols for CT angiography and images were reconstructed with different filter kernels. The measured CT number (HU) and diameter of each object were analyzed on three clinical postprocessing workstations. From the resultant data, a mathematical formula was derived based on absorption function exp(-μ * d) to demonstrate the relation between measured CT numbers and object diameters. Results: The percentage reduction in measured CT number (HU) for the group of selected filter kernels, apparent during CT angiography, is dependent only on the object size (plaque or vessel diameter). The derived formula of the form 1-c * exp(-a * d b ) showed reduction in CT number for objects between 0.5 and 5 mm in diameter, with asymptote reaching background noise for small objects with diameters nearing the CT in-plane resolution (0.35 mm). No reduction was observed for the objects with diameters equal or larger than 5 mm. Conclusions: A clear mathematical relationship exists between object diameter and reduction in measured CT number in HU. This function is independent of exposure parameters and inherent attenuation properties of the objects studied. Future developments include the incorporation of this mathematical model function into quantification software in order to automatically

  10. Optimization of sup 125 I ophthalmic plaque brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Astrahan, M.A.; Luxton, G.; Jozsef, G.; Liggett, P.E.; Petrovich, Z. (Univ. of Southern California School of Medicine, Los Angeles (USA))

    1990-11-01

    Episcleral plaques containing {sup 125}I sources are often used in the treatment of ocular melanoma. Within four years post-treatment, however, the majority of patients experience some visual loss due to radiation retinopathy. The high incidence of late complications suggests that careful treatment optimization may lead to improved outcome. The goal of optimization would be to reduce the magnitude of vision-limiting complications without compromising tumor control. We have developed a three-dimensional computer model for ophthalmic plaque therapy which permits us to explore the potential of various optimization strategies. One simple strategy which shows promise is to maximize the ratio of dose to the tumor apex (T) compared to dose to the macula (M). By modifying the parameters of source location, activity distribution, source orientation, and shielding we find that the calculated T:M ratio can be varied by a factor of 2 for a common plaque design and posterior tumor location. Margins and dose to the tumor volume remain essentially unchanged.

  11. Stance disturbance in multiple sclerosis: brainstem lesions and posturographic assessment

    Directory of Open Access Journals (Sweden)

    Peter Schalek

    2012-01-01

    Full Text Available

    Background. Balance disorders are commonly evidenced during the course of multiple sclerosis (MS. The aim of this study is to report characteristics of MS patient stance control disorders, measured by means of posturography and related to the brainstem lesions.

    Methods. Thirty-eight patients affected by MS, mildly to moderately disable according to Kurtzke’s Expanded Disability Status Scale, underwent a complete clinical neurological and vestibular evaluation and brain MRI scanning. All patients were then tested on a static posturography platform (Tetrax, Israel in four conditions: eyes open and closed standing on a firm surface and on a foam pad.

    Results. Clinical and/or MRI evidence of brainstem involvement was observed in 55.3 % of patients. When brainstem lesion was detected, Fourier analysis showed a typical pattern characterized by inversion of the  0- 0.1 Hz and  0.1 - 0.25 Hz. frequency bands.

    Conclusions. MS leads to pervasive postural disturbances in the majority of subjects, including the visuo-vestibular loops and proprioception involving vestibulo-spinal pathways in at least 55.3 % of patients. Our results may also suggest the presence of Fourier inversion in patients with brainstem lesions.


  12. Age-Related Changes in Binaural Interaction at Brainstem Level.

    Science.gov (United States)

    Van Yper, Lindsey N; Vermeire, Katrien; De Vel, Eddy F J; Beynon, Andy J; Dhooge, Ingeborg J M

    2016-01-01

    Age-related hearing loss hampers the ability to understand speech in adverse listening conditions. This is attributed to a complex interaction of changes in the peripheral and central auditory system. One aspect that may deteriorate across the lifespan is binaural interaction. The present study investigates binaural interaction at the level of the auditory brainstem. It is hypothesized that brainstem binaural interaction deteriorates with advancing age. Forty-two subjects of various age participated in the study. Auditory brainstem responses (ABRs) were recorded using clicks and 500 Hz tone-bursts. ABRs were elicited by monaural right, monaural left, and binaural stimulation. Binaural interaction was investigated in two ways. First, grand averages of the binaural interaction component were computed for each age group. Second, wave V characteristics of the binaural ABR were compared with those of the summed left and right ABRs. Binaural interaction in the click ABR was demonstrated by shorter latencies and smaller amplitudes in the binaural compared with the summed monaural responses. For 500 Hz tone-burst ABR, no latency differences were found. However, amplitudes were significantly smaller in the binaural than summed monaural condition. An age-effect was found for 500 Hz tone-burst, but not for click ABR. Brainstem binaural interaction seems to decline with age. Interestingly, these changes seem to be stimulus-dependent.

  13. Intraparenchymal papillary meningioma of brainstem: case report and literature review

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    Jiang Xiao-Bing

    2012-01-01

    Full Text Available Abstract Both intraparenchymal papillary meningioma and papillary meningioma with cyst formation of brainstem have never been reported. The authors present an extremely rare case of patient with intraparenchymal papillary meningioma of brainstem. A 23-year-old Chinese male presented with a 4-month history of progressive left upper limb and facial nerve palsy. Magnetic resonance imaging revealed a cystic-solid, heterogeneously enhancing mass in pons and right cerebral peduncle with no dural attachment. The tumor was totally removed via subtemporal approach. During surgery, the lesion was found to be completely intraparenchymal. Histological and immunohistochemical examinations were compatible with the diagnosis of papillary meningioma. The lesion recurred nine months after primary surgery, a second surgery followed by radiotherapy was performed. Till to now (nearly 2 years after the treatment, the patient is tumor free survival. Intraparenchymal meningioma of brainstem with cystic formation is very rare, however, it should be considered as a differential diagnosis of a brainstem neoplasm. The present case strongly recommended that postoperative radiotherapy was essential for the patients with papillary meningiomas.

  14. Matrix vesicles in the fibrous cap of atherosclerotic plaque: possible contribution to plaque rupture.

    Science.gov (United States)

    Bobryshev, Y V; Killingsworth, M C; Lord, R S A; Grabs, A J

    2008-10-01

    Plaque rupture is the most common type of plaque complication and leads to acute ischaemic events such as myocardial infarction and stroke. Calcification has been suggested as a possible indicator of plaque instability. Although the role of matrix vesicles in the initial stages of arterial calcification has been recognized, no studies have yet been carried out to examine a possible role of matrix vesicles in plaque destabilization. Tissue specimens selected for the present study represented carotid specimens obtained from patients undergoing carotid endarterectomy. Serial frozen cross-sections of the tissue specimens were cut and mounted on glass slides. The thickness of the fibrous cap (FCT) in each advanced atherosclerotic lesion, containing a well developed lipid/necrotic core, was measured at its narrowest sites in sets of serial sections. According to established criteria, atherosclerotic plaque specimens were histologically subdivided into two groups: vulnerable plaques with thin fibrous caps (FCT <100 microm) and presumably stable plaques, in which fibrous caps were thicker than 100 microm. Twenty-four carotid plaques (12 vulnerable and 12 presumably stable plaques) were collected for the present analysis of matrix vesicles in fibrous caps. In order to provide a sufficient number of representative areas from each plaque, laser capture microdissection (LCM) was carried out. The quantification of matrix vesicles in ultrathin sections of vulnerable and stable plaques revealed that the numbers of matrix vesicles were significantly higher in fibrous caps of vulnerable plaques than those in stable plaques (8.908+0.544 versus 6.208+0.467 matrix vesicles per 1.92 microm2 standard area; P= 0.0002). Electron microscopy combined with X-ray elemental microanalysis showed that some matrix vesicles in atherosclerotic plaques were undergoing calcification and were characterized by a high content of calcium and phosphorus. The percentage of calcified matrix vesicles

  15. The Structural, Functional and Molecular Organization of the Brainstem

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    Rudolf eNieuwenhuys

    2011-06-01

    Full Text Available According to Wilhelm His (1891, 1893 the brainstem consists of two longitudinal zones, the dorsal alar plate (sensory in nature and the ventral basal plate (motor in nature. Johnston and Herrick indicated that both plates can be subdivided into separate somatic and visceral zones, distinguishing somatosensory and viscerosensory zones within the alar plate, and visceromotor and somatomotor zones within the basal plate. To test the validity of this ‘four-functional-zones’ concept, I developed a topological procedure, surveying the spatial relationships of the various cell masses in the brainstem in a single figure. Brainstems of 16 different anamniote species were analyzed, and revealed that the brainstems are clearly divisible into four morphological zones, which correspond largely with the functional zones of Johnston and Herrick. Exceptions include (1 the magnocellular vestibular nucleus situated in the viscerosensory zone; (2 the basal plate containing a number of evidently non-motor centres (superior and inferior olives. Nevertheless the ‘functional zonal model’ has explanatory value. Thus, it is possible to interpret certain brain specializations related to particular behavioural profiles, as ‘local hypertrophies’ of one or two functional columns. Recent developmental molecular studies on brains of birds and mammals confirmed the presence of longitudinal zones, and also showed molecularly defined transverse bands or neuromeres throughout development. The intersecting boundaries of the longitudinal zones and the transverse bands appeared to delimit radially arranged histogenetic domains. Because neuromeres have been observed in embryonic and larval stages of numerous anamniote species, it may be hypothesized that the brainstems of all vertebrates share a basic organizational plan, in which intersecting longitudinal and transverse zones form fundamental histogenetic and genoarchitectonic units.

  16. Multidetector row computed tomography may accurately estimate plaque vulnerability. Does MDCT accurately estimate plaque vulnerability? (Pro)

    International Nuclear Information System (INIS)

    Komatsu, Sei; Imai, Atsuko; Kodama, Kazuhisa

    2011-01-01

    Over the past decade, multidetector row computed tomography (MDCT) has become the most reliable and established of the noninvasive examination techniques for detecting coronary heart disease. Now MDCT is chasing intravascular ultrasound (IVUS) in terms of spatial resolution. Among the components of vulnerable plaque, MDCT may detect lipid-rich plaque, the lipid pool, and calcified spots using computed tomography number. Plaque components are detected by MDCT with high accuracy compared with IVUS and angioscopy when assessing vulnerable plaque. The TWINS study and TOGETHAR trial demonstrated that angioscopic loss of yellow color occurred independently of volumetric plaque change by statin therapy. These 2 studies showed that plaque stabilization and regression reflect independent processes mediated by different mechanisms and time course. Noncalcified plaque and/or low-density plaque was found to be the strongest predictor of cardiac events, regardless of lesion severity, and act as a potential marker of plaque vulnerability. MDCT may be an effective tool for early triage of patients with chest pain who have a normal electrocardiogram (ECG) and cardiac enzymes in the emergency department. MDCT has the potential ability to analyze coronary plaque quantitatively and qualitatively if some problems are resolved. MDCT may become an essential tool for detecting and preventing coronary artery disease in the future. (author)

  17. Plaque echodensity and textural features are associated with histologic carotid plaque instability.

    Science.gov (United States)

    Doonan, Robert J; Gorgui, Jessica; Veinot, Jean P; Lai, Chi; Kyriacou, Efthyvoulos; Corriveau, Marc M; Steinmetz, Oren K; Daskalopoulou, Stella S

    2016-09-01

    Carotid plaque echodensity and texture features predict cerebrovascular symptomatology. Our purpose was to determine the association of echodensity and textural features obtained from a digital image analysis (DIA) program with histologic features of plaque instability as well as to identify the specific morphologic characteristics of unstable plaques. Patients scheduled to undergo carotid endarterectomy were recruited and underwent carotid ultrasound imaging. DIA was performed to extract echodensity and textural features using Plaque Texture Analysis software (LifeQ Medical Ltd, Nicosia, Cyprus). Carotid plaque surgical specimens were obtained and analyzed histologically. Principal component analysis (PCA) was performed to reduce imaging variables. Logistic regression models were used to determine if PCA variables and individual imaging variables predicted histologic features of plaque instability. Image analysis data from 160 patients were analyzed. Individual imaging features of plaque echolucency and homogeneity were associated with a more unstable plaque phenotype on histology. These results were independent of age, sex, and degree of carotid stenosis. PCA reduced 39 individual imaging variables to five PCA variables. PCA1 and PCA2 were significantly associated with overall plaque instability on histology (both P = .02), whereas PCA3 did not achieve statistical significance (P = .07). DIA features of carotid plaques are associated with histologic plaque instability as assessed by multiple histologic features. Importantly, unstable plaques on histology appear more echolucent and homogeneous on ultrasound imaging. These results are independent of stenosis, suggesting that image analysis may have a role in refining the selection of patients who undergo carotid endarterectomy. Copyright © 2016 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.

  18. PET/CT for atherosclerotic plaque imaging

    International Nuclear Information System (INIS)

    Ben-Haim, S.; Technion Institute of Technology, Haifa; Israel, O.; Rambam Medical Center, Haifa

    2006-01-01

    Atherosclerosis is one of the leading causes of morbidity and mortality in the world. Rupture of atherosclerotic plaques and thrombi formation are the primary mechanisms of myocardial infarction or cerebrovascular accident. Angiography is considered to represent the gold standard technique for imaging of the arterial lumen. However, in recent years it has been realized that the primary determinant of the atherosclerotic plaque stability is the composition of the plaque and other imaging modalities have been suggested. The purpose of this review is to briefly summarize the knowledge accumulated to present date regarding the potential role of fluo deoxyglucose imaging in the assessment of atherosclerosis and to compare this modality to additional available imaging approaches for the detection of vulnerable plaques

  19. Brainstem dose is associated with patient-reported acute fatigue in head and neck cancer radiation therapy.

    Science.gov (United States)

    Ferris, Matthew J; Zhong, Jim; Switchenko, Jeffrey M; Higgins, Kristin A; Cassidy, Richard J; McDonald, Mark W; Eaton, Bree R; Patel, Kirtesh R; Steuer, Conor E; Baddour, H Michael; Miller, Andrew H; Bruner, Deborah W; Xiao, Canhua; Beitler, Jonathan J

    2018-01-01

    Radiation (RT) dose to the central nervous system (CNS) has been implicated as a contributor to treatment-related fatigue in head and neck cancer (HNC) patients undergoing radiation therapy (RT). This study evaluates the association of RT dose to CNS structures with patient-reported (PRO) fatigue scores in a population of HNC patients. At pre-RT (baseline), 6th week of RT, and 1-month post-RT time points, Multidimensional Fatigue Inventory (MFI-20) scores were prospectively obtained from 124 patients undergoing definitive treatment for HNC. Medulla, pons, midbrain, total brainstem, cerebellum, posterior fossa, and pituitary dosimetry were evaluated using summary statistics and dose-volume histograms, and associations with MFI-20 scores were analyzed. Maximum dose (Dmax) to the brainstem and medulla was significantly associated with MFI-20 scores at 6th week of RT and 1-month post-RT time points, after controlling for baseline scores (p<0.05). Each 1Gy increase in medulla Dmax resulted in an increase in total MFI-20 score over baseline of 0.30 (p=0.026), and 0.25 (p=0.037), at the 6th week of RT and 1-month post-RT, respectively. Each 1Gy increase in brainstem Dmax resulted in an increase in total MFI-20 score over baseline of 0.30 (p=0.027), and 0.25 (p=0.037) at the 6th week of RT, 1-month post-RT, respectively. Statistically significant associations were not found between dosimetry for the other CNS structures and MFI-20 scores. In this analysis of PRO fatigue scores from a population of patients undergoing definitive RT for HNC, maximum dose to the brainstem and medulla was associated with a significantly increased risk of acute patient fatigue. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Diffusion tensor imaging of the brainstem in children with achondroplasia.

    Science.gov (United States)

    Bosemani, Thangamadhan; Orman, Gunes; Carson, Kathryn A; Meoded, Avner; Huisman, Thierry A G M; Poretti, Andrea

    2014-11-01

    The aims of this study were to compare, using diffusion tensor imaging (DTI) of the brainstem, microstructural integrity of the white matter in children with achondroplasia and age-matched participants and to correlate the severity of craniocervical junction (CCJ) narrowing and neurological findings with DTI scalars in children with achondroplasia. This study also aimed to assess the potential role of fibroblast growth factor receptor type 3 on white matter microstructure. Diffusion tensor imaging was performed using a 1.5T magnetic resonance scanner and balanced pairs of diffusion gradients along 20 non-collinear directions. Measurements were obtained from regions of interest, sampled in each pontine corticospinal tract (CST), medial lemniscus, and middle cerebellar peduncle, as well as in the lower brainstem and centrum semiovale, for fractional anisotropy and for mean, axial, and radial diffusivity. In addition, a severity score for achondroplasia was assessed by measuring CCJ narrowing. Eight patients with achondroplasia (seven males, one female; mean age 5y 6mo, range 1y 1mo-15y 1mo) and eight age- and sex-matched comparison participants (mean age 5y 2mo, range 1y 1mo-14y 11mo) were included in this study. Fractional anisotropy was lower and mean diffusivity and radial diffusivity were higher in the lower brainstem of patients with achondroplasia than in age-matched comparison participants. The CST and middle cerebellar peduncle of the participants showed increases in mean, axial, and radial diffusivity. Fractional anisotropy in the lower brainstem was negatively correlated with the degree of CCJ narrowing. No differences in the DTI metrics of the centrum semiovale were observed between the two groups. The reduction in fractional anisotropy and increase in diffusivities in the lower brainstem of participants with achondroplasia may reflect secondary encephalomalacic degeneration and cavitation of the affected white matter tracts as shown by histology. In

  1. Carotid plaque age is a feature of plaque stability inversely related to levels of plasma insulin.

    Directory of Open Access Journals (Sweden)

    Sara Hägg

    Full Text Available BACKGROUND: The stability of atherosclerotic plaques determines the risk for rupture, which may lead to thrombus formation and potentially severe clinical complications such as myocardial infarction and stroke. Although the rate of plaque formation may be important for plaque stability, this process is not well understood. We took advantage of the atmospheric (14C-declination curve (a result of the atomic bomb tests in the 1950s and 1960s to determine the average biological age of carotid plaques. METHODOLOGY/PRINCIPAL FINDING: The cores of carotid plaques were dissected from 29 well-characterized, symptomatic patients with carotid stenosis and analyzed for (14C content by accelerator mass spectrometry. The average plaque age (i.e. formation time was 9.6±3.3 years. All but two plaques had formed within 5-15 years before surgery. Plaque age was not associated with the chronological ages of the patients but was inversely related to plasma insulin levels (p = 0.0014. Most plaques were echo-lucent rather than echo-rich (2.24±0.97, range 1-5. However, plaques in the lowest tercile of plaque age (most recently formed were characterized by further instability with a higher content of lipids and macrophages (67.8±12.4 vs. 50.4±6.2, p = 0.00005; 57.6±26.1 vs. 39.8±25.7, p<0.0005, respectively, less collagen (45.3±6.1 vs. 51.1±9.8, p<0.05, and fewer smooth muscle cells (130±31 vs. 141±21, p<0.05 than plaques in the highest tercile. Microarray analysis of plaques in the lowest tercile also showed increased activity of genes involved in immune responses and oxidative phosphorylation. CONCLUSIONS/SIGNIFICANCE: Our results show, for the first time, that plaque age, as judge by relative incorporation of (14C, can improve our understanding of carotid plaque stability and therefore risk for clinical complications. Our results also suggest that levels of plasma insulin might be involved in determining carotid plaque age.

  2. A new inexpensive customized plaque for choroidal melanoma iodine-125 plaque therapy

    International Nuclear Information System (INIS)

    Vine, A.K.; Tenhaken, R.K.; Diaz, R.F.; Maxson, B.B.; Lichter, A.S.

    1989-01-01

    The authors have developed a new inexpensive precious metal alloy plaque for use in customized iodine-125 plaque therapy. Each plaque is formed from two flat circular gold/palladium foils which are used in dental crown work. Using a simple manual mechanism, the two forms are stamped over a customized acrylic die shaped to the dimensions of the tumor base plus a 2-mm margin. Completed plaques consist of a back wall, a 2-mm side wall, and a 1.5-mm wide lip with holes for suture placement. Advantages include: simple construction from inexpensive components, customized shape, and iodine seeds that are readily visible on plane radiographs

  3. Prescription dose and fractionation predict improved survival after stereotactic radiotherapy for brainstem metastases

    Directory of Open Access Journals (Sweden)

    Leeman Jonathan E

    2012-07-01

    Full Text Available Abstract Background Brainstem metastases represent an uncommon clinical presentation that is associated with a poor prognosis. Treatment options are limited given the unacceptable risks associated with surgical resection in this location. However, without local control, symptoms including progressive cranial nerve dysfunction are frequently observed. The objective of this study was to determine the outcomes associated with linear accelerator-based stereotactic radiotherapy or radiosurgery (SRT/SRS of brainstem metastases. Methods We retrospectively reviewed 38 tumors in 36 patients treated with SRT/SRS between February 2003 and December 2011. Treatment was delivered with the Cyberknife™ or Trilogy™ radiosurgical systems. The median age of patients was 62 (range: 28–89. Primary pathologies included 14 lung, 7 breast, 4 colon and 11 others. Sixteen patients (44% had received whole brain radiation therapy (WBRT prior to SRT/SRS; ten had received prior SRT/SRS at a different site (28%. The median tumor volume was 0.94 cm3 (range: 0.01-4.2 with a median prescription dose of 17 Gy (range: 12–24 delivered in 1–5 fractions. Results Median follow-up for the cohort was 3.2 months (range: 0.4-20.6. Nineteen patients (52% had an MRI follow-up available for review. Of these, one patient experienced local failure corresponding to an actuarial 6-month local control of 93%. Fifteen of the patients with available follow-up imaging (79% experienced intracranial failure outside of the treatment volume. The median time to distant intracranial failure was 2.1 months. Six of the 15 patients with distant intracranial failure (40% had received previous WBRT. The actuarial overall survival rates at 6- and 12-months were 27% and 8%, respectively. Predictors of survival included Graded Prognostic Assessment (GPA score, greater number of treatment fractions, and higher prescription dose. Three patients experienced acute treatment-related toxicity consisting of

  4. Accurate estimation of dose distributions inside an eye irradiated with {sup 106}Ru plaques

    Energy Technology Data Exchange (ETDEWEB)

    Brualla, L.; Sauerwein, W. [Universitaetsklinikum Essen (Germany). NCTeam, Strahlenklinik; Sempau, J.; Zaragoza, F.J. [Universitat Politecnica de Catalunya, Barcelona (Spain). Inst. de Tecniques Energetiques; Wittig, A. [Marburg Univ. (Germany). Klinik fuer Strahlentherapie und Radioonkologie

    2013-01-15

    Background: Irradiation of intraocular tumors requires dedicated techniques, such as brachytherapy with {sup 106}Ru plaques. The currently available treatment planning system relies on the assumption that the eye is a homogeneous water sphere and on simplified radiation transport physics. However, accurate dose distributions and their assessment demand better models for both the eye and the physics. Methods: The Monte Carlo code PENELOPE, conveniently adapted to simulate the beta decay of {sup 106}Ru over {sup 106}Rh into {sup 106}Pd, was used to simulate radiation transport based on a computerized tomography scan of a patient's eye. A detailed geometrical description of two plaques (models CCA and CCB) from the manufacturer BEBIG was embedded in the computerized tomography scan. Results: The simulations were firstly validated by comparison with experimental results in a water phantom. Dose maps were computed for three plaque locations on the eyeball. From these maps, isodose curves and cumulative dose-volume histograms in the eye and for the structures at risk were assessed. For example, it was observed that a 4-mm anterior displacement with respect to a posterior placement of a CCA plaque for treating a posterior tumor would reduce from 40 to 0% the volume of the optic disc receiving more than 80 Gy. Such a small difference in anatomical position leads to a change in the dose that is crucial for side effects, especially with respect to visual acuity. The radiation oncologist has to bring these large changes in absorbed dose in the structures at risk to the attention of the surgeon, especially when the plaque has to be positioned close to relevant tissues. Conclusion: The detailed geometry of an eye plaque in computerized and segmented tomography of a realistic patient phantom was simulated accurately. Dose-volume histograms for relevant anatomical structures of the eye and the orbit were obtained with unprecedented accuracy. This represents an important step

  5. Accurate estimation of dose distributions inside an eye irradiated with 106Ru plaques

    International Nuclear Information System (INIS)

    Brualla, L.; Sauerwein, W.; Sempau, J.; Zaragoza, F.J.; Wittig, A.

    2013-01-01

    Background: Irradiation of intraocular tumors requires dedicated techniques, such as brachytherapy with 106 Ru plaques. The currently available treatment planning system relies on the assumption that the eye is a homogeneous water sphere and on simplified radiation transport physics. However, accurate dose distributions and their assessment demand better models for both the eye and the physics. Methods: The Monte Carlo code PENELOPE, conveniently adapted to simulate the beta decay of 106 Ru over 106 Rh into 106 Pd, was used to simulate radiation transport based on a computerized tomography scan of a patient's eye. A detailed geometrical description of two plaques (models CCA and CCB) from the manufacturer BEBIG was embedded in the computerized tomography scan. Results: The simulations were firstly validated by comparison with experimental results in a water phantom. Dose maps were computed for three plaque locations on the eyeball. From these maps, isodose curves and cumulative dose-volume histograms in the eye and for the structures at risk were assessed. For example, it was observed that a 4-mm anterior displacement with respect to a posterior placement of a CCA plaque for treating a posterior tumor would reduce from 40 to 0% the volume of the optic disc receiving more than 80 Gy. Such a small difference in anatomical position leads to a change in the dose that is crucial for side effects, especially with respect to visual acuity. The radiation oncologist has to bring these large changes in absorbed dose in the structures at risk to the attention of the surgeon, especially when the plaque has to be positioned close to relevant tissues. Conclusion: The detailed geometry of an eye plaque in computerized and segmented tomography of a realistic patient phantom was simulated accurately. Dose-volume histograms for relevant anatomical structures of the eye and the orbit were obtained with unprecedented accuracy. This represents an important step toward an optimized

  6. SU-F-T-392: Superior Brainstem and Cochlea Sparing with VMAT for Glioblastoma Multiforme

    Energy Technology Data Exchange (ETDEWEB)

    Briere, TM; McAleer, MF; Levy, LB; Yang, JN; Anderson, MD [Cancer Ctr., Houston, TX (United States)

    2016-06-15

    Purpose: Volumetric arc therapy (VMAT) can provide similar target coverage and normal tissue sparing as IMRT but with shorter treatment times. At our institution VMAT was adopted for the treatment glioblastoma multiforme (GBM) after a small number of test plans demonstrated its non-inferiority. In this study, we compare actual clinical treatment plans for a larger cohort of patients treated with either VMAT or IMRT. Methods: 90 GBM patients were included in this study, 45 treated with IMRT and 45 with VMAT. All planning target volumes (PTVs) were prescribed a dose of 50 Gy, with a simultaneous integrated boost to 60 Gy. Most IMRT plans used 5 non-coplanar beams, while most VMAT plans used 2 coplanar beams. Statistical analysis was performed using Fisher’s exact test or the Wilcoxon-Mann-Whitney rank sum test. Included in the analysis were patient and treatment characteristics as well as the doses to the target volumes and organs at risk. Results: Treatment times for the VMAT plans were reduced by 5 minutes compared with IMRT. The PTV coverage was similar, with at least 95% covered for all plans, while the median boost PTV dose differed by 0.1 Gy between the IMRT and VMAT cohorts. The doses to the brain, optic chiasm, optic nerves and eyes were not significantly different. The mean dose to the brainstem, however, was 9.4 Gy less with VMAT (p<0.001). The dose to the ipsilateral and contralateral cochleae were respectively 19.7 and 9.5 Gy less (p<0.001). Conclusion: Comparison of clinical treatment plans for separate IMRT and VMAT cohorts demonstrates that VMAT can save substantial treatment time while providing similar target coverage and superior sparing of the brainstem and cochleae. To our knowledge this is the first study to demonstrate this benefit of VMAT in the management of GBM.

  7. Relationship between structural brainstem and brain plasticity and lower-limb training in spinal cord injury: a longitudinal pilot study

    Science.gov (United States)

    Villiger, Michael; Grabher, Patrick; Hepp-Reymond, Marie-Claude; Kiper, Daniel; Curt, Armin; Bolliger, Marc; Hotz-Boendermaker, Sabina; Kollias, Spyros; Eng, Kynan; Freund, Patrick

    2015-01-01

    Rehabilitative training has shown to improve significantly motor outcomes and functional walking capacity in patients with incomplete spinal cord injury (iSCI). However, whether performance improvements during rehabilitation relate to brain plasticity or whether it is based on functional adaptation of movement strategies remain uncertain. This study assessed training improvement-induced structural brain plasticity in chronic iSCI patients using longitudinal MRI. We used tensor-based morphometry (TBM) to analyze longitudinal brain volume changes associated with intensive virtual reality (VR)-augmented lower limb training in nine traumatic iSCI patients. The MRI data was acquired before and after a 4-week training period (16–20 training sessions). Before training, voxel-based morphometry (VBM) and voxel-based cortical thickness (VBCT) assessed baseline morphometric differences in nine iSCI patients compared to 14 healthy controls. The intense VR-augmented training of limb control improved significantly balance, walking speed, ambulation, and muscle strength in patients. Retention of clinical improvements was confirmed by the 3–4 months follow-up. In patients relative to controls, VBM revealed reductions of white matter volume within the brainstem and cerebellum and VBCT showed cortical thinning in the primary motor cortex. Over time, TBM revealed significant improvement-induced volume increases in the left middle temporal and occipital gyrus, left temporal pole and fusiform gyrus, both hippocampi, cerebellum, corpus callosum, and brainstem in iSCI patients. This study demonstrates structural plasticity at the cortical and brainstem level as a consequence of VR-augmented training in iSCI patients. These structural changes may serve as neuroimaging biomarkers of VR-augmented lower limb neurorehabilitation in addition to performance measures to detect improvements in rehabilitative training. PMID:25999842

  8. Automatic hearing loss detection system based on auditory brainstem response

    International Nuclear Information System (INIS)

    Aldonate, J; Mercuri, C; Reta, J; Biurrun, J; Bonell, C; Gentiletti, G; Escobar, S; Acevedo, R

    2007-01-01

    Hearing loss is one of the pathologies with the highest prevalence in newborns. If it is not detected in time, it can affect the nervous system and cause problems in speech, language and cognitive development. The recommended methods for early detection are based on otoacoustic emissions (OAE) and/or auditory brainstem response (ABR). In this work, the design and implementation of an automated system based on ABR to detect hearing loss in newborns is presented. Preliminary evaluation in adults was satisfactory

  9. Thalamic, brainstem, and cerebellar glucose metabolism in the hemiplegic monkey

    Energy Technology Data Exchange (ETDEWEB)

    Shimoyama, I.; Dauth, G.W.; Gilman, S.; Frey, K.A.; Penney, J.B. Jr.

    1988-12-01

    Unilateral ablation of cerebral cortical areas 4 and 6 of Brodmann in the macaque monkey results in a contralateral hemiplegia that resolves partially with time. During the phase of dense hemiplegia, local cerebral metabolic rate for glucose (1CMRG1c) is decreased significantly in most of the thalamic nuclei ipsilateral to the ablation, and there are slight contralateral decreases. The lCMRGlc is reduced bilaterally in most of the brainstem nuclei and bilaterally in the deep cerebellar nuclei, but only in the contralateral cerebellar cortex. During the phase of partial motor recovery, lCMRGlc is incompletely restored in many of the thalamic nuclei ipsilateral to the ablation and completely restored in the contralateral nuclei. In the brainstem and deep cerebellar nuclei, poor to moderate recovery occurs bilaterally. Moderate recovery occurs in the contralateral cerebellar cortex. The findings demonstrate that a unilateral cerebral cortical lesion strongly affects lCMRGlc in the thalamus ipsilaterally and in the cerebellar cortex contralaterally, but in the brainstem bilaterally. Partial recovery of lCMRGlc accompanies the progressive motor recovery. The structures affected include those with direct, and also those with indirect, connections to the areas ablated.

  10. Comprehensive evaluation of a child with an auditory brainstem implant.

    Science.gov (United States)

    Eisenberg, Laurie S; Johnson, Karen C; Martinez, Amy S; DesJardin, Jean L; Stika, Carren J; Dzubak, Danielle; Mahalak, Mandy Lutz; Rector, Emily P

    2008-02-01

    We had an opportunity to evaluate an American child whose family traveled to Italy to receive an auditory brainstem implant (ABI). The goal of this evaluation was to obtain insight into possible benefits derived from the ABI and to begin developing assessment protocols for pediatric clinical trials. Case study. Tertiary referral center. Pediatric ABI Patient 1 was born with auditory nerve agenesis. Auditory brainstem implant surgery was performed in December, 2005, in Verona, Italy. The child was assessed at the House Ear Institute, Los Angeles, in July 2006 at the age of 3 years 11 months. Follow-up assessment has continued at the HEAR Center in Birmingham, Alabama. Auditory brainstem implant. Performance was assessed for the domains of audition, speech and language, intelligence and behavior, quality of life, and parental factors. Patient 1 demonstrated detection of sound, speech pattern perception with visual cues, and inconsistent auditory-only vowel discrimination. Language age with signs was approximately 2 years, and vocalizations were increasing. Of normal intelligence, he exhibited attention deficits with difficulty completing structured tasks. Twelve months later, this child was able to identify speech patterns consistently; closed-set word identification was emerging. These results were within the range of performance for a small sample of similarly aged pediatric cochlear implant users. Pediatric ABI assessment with a group of well-selected children is needed to examine risk versus benefit in this population and to analyze whether open-set speech recognition is achievable.

  11. Dose Sparing of Brainstem and Spinal Cord for Re-Irradiating Recurrent Head and Neck Cancer with Intensity-Modulated Radiotherapy

    International Nuclear Information System (INIS)

    Chen, Chin-Cheng; Lee, Chen-Chiao; Mah, Dennis; Sharma, Rajiv; Landau, Evan; Garg, Madhur; Wu, Andrew

    2011-01-01

    Because of the dose limit for critical structures such as brainstem and spinal cord, administering a dose of 60 Gy to patients with recurrent head and neck cancer is challenging for those who received a previous dose of 60-70 Gy. Specifically, previously irradiated head and neck patients may have received doses close to the tolerance limit to their brainstem and spinal cord. In this study, a reproducible intensity-modulated radiation therapy (IMRT) treatment design is presented to spare the doses to brainstem and spinal cord, with no compromise of prescribed dose delivery. Between July and November 2008, 7 patients with previously irradiated, recurrent head and neck cancers were treated with IMRT. The jaws of each field were set fixed with the goal of shielding the brainstem and spinal cord at the sacrifice of partial coverage of the planning target volume (PTV) from any particular beam orientation. Beam geometry was arranged to have sufficient coverage of the PTV and ensure that the constraints of spinal cord o , patients could be treated by 18 fields. Six patients met these criteria and were treated in 25 minutes per fraction. One patient exceeded a 30 o Cobb's angle and was treated by 31 fields in 45 minutes per fraction. We have demonstrated a new technique for retreatment of head and neck cancers. The angle of cervical spine curvature plays an important role in the efficiency and effectiveness of our approach.

  12. Effects of myelin or cell body brainstem lesions on 3-channel Lissajous' trajectories of feline auditory brainstem evoked potentials

    OpenAIRE

    Pratt, H; Zaaroor, M; Bleich, N; Starr, A

    1991-01-01

    Auditory brainstem evoked potentials (ABEP) were recorded from 16 awake cats to obtain 3-Channel Lissajous' Trajectories (3CLTs) using three orthogonal differential electrode configurations (nasion - midline nuchal ridge, left - right mastoids, vertex - midline under the mandible). Potentials, evoked by monaural 80 dBnHL (re. human threshold) clicks, were studied before, and up to 7 weeks after inducing neuronal lesions localized to the cochlear nucleus (CN) or the superior olivary complex (S...

  13. Characteristic detected on computed tomography angiography predict coronary artery plaque progression in non-culprit lesions

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Ya Hang; Zhou, Jia Zhou; Zhou, Ying; Yang, Xiaobo; Yang, Jun Jie; Chen, Yun Dai [Dept. of Cardiology, Chinese PLA General Hospital, Beijing (China)

    2017-06-15

    This study sought to determine whether variables detected on coronary computed tomography angiography (CCTA) would predict plaque progression in non-culprit lesions (NCL). In this single-center trial, we analyzed 103 consecutive patients who were undergoing CCTA and percutaneous coronary intervention (PCI) for culprit lesions. Follow-up CCTA was scheduled 12 months after the PCI, and all patients were followed for 3 years after their second CCTA examination. High-risk plaque features and epicardial adipose tissue (EAT) volume were assessed by CCTA. Each NCL stenosis grade was compared visually between two CCTA scans to detect plaque progression, and patients were stratified into two groups based on this. Logistic regression analysis was used to evaluate the factors that were independently associated with plaque progression in NCLs. Time-to-event curves were compared using the log-rank statistic. Overall, 34 of 103 patients exhibited NCL plaque progression (33%). Logistic regression analyses showed that the NCL progression was associated with a history of ST-elevated myocardial infarction (odds ratio [OR] = 5.855, 95% confidence interval [CI] = 1.391–24.635, p = 0.016), follow-up low-density lipoprotein cholesterol level (OR = 6.832, 95% CI = 2.103–22.200, p = 0.001), baseline low-attenuation plaque (OR = 7.311, 95% CI = 1.242–43.028, p = 0.028) and EAT (OR = 1.015, 95% CI = 1.000–1.029, p = 0.044). Following the second CCTA examination, major adverse cardiac events (MACEs) were observed in 12 patients, and NCL plaque progression was significantly associated with future MACEs (log rank p = 0.006). Noninvasive assessment of NCLs by CCTA has potential prognostic value.

  14. Atherosclerotic plaque component segmentation in combined carotid MRI and CTA data incorporating class label uncertainty

    DEFF Research Database (Denmark)

    van Engelen, Arna; Niessen, Wiro J.; Klein, Stefan

    2014-01-01

    Atherosclerotic plaque composition can indicate plaque vulnerability. We segment atherosclerotic plaque components from the carotid artery on a combination of in vivo MRI and CT-angiography (CTA) data using supervised voxelwise classification. In contrast to previous studies the ground truth...... for training is directly obtained from 3D registration with histology for fibrous and lipid-rich necrotic tissue, and with [Formula: see text]CT for calcification. This registration does, however, not provide accurate voxelwise correspondence. We therefore evaluate three approaches that incorporate uncertainty......), II) samples are weighted by the local contour distance of the lumen and outer wall between histology and in vivo data, and III) 10% of each class is rejected by Gaussian outlier rejection. Classification was evaluated on the relative volumes (% of tissue type in the vessel wall) for calcified...

  15. DECT evaluation of noncalcified coronary artery plaque

    Energy Technology Data Exchange (ETDEWEB)

    Ravanfar Haghighi, Rezvan [Medical Imaging Research Center and Colorectal Research Center, Shiraz University of Medical Science, Shiraz 719 363 5899 (Iran, Islamic Republic of); Chatterjee, S. [BGVS Chemical Engineering Building (Old), Indian Institute of Science, Bangalore 560012 (India); Tabin, Milo; Singh, Rishi P.; Sharma, Munish; Krishna, Karthik [Department of Forensic Medicine, All India Institute of Medical Sciences, New Delhi 110029 (India); Sharma, Sanjiv; Jagia, Priya [Department of Cardiac-Radiology, All India Institute of Medical Sciences, New Delhi 110029 (India); Ray, Ruma; Arava, Sudhir [Department of Pathology, All India Institute of Medical Sciences, New Delhi 110029 (India); Yadav, Rakesh [Department of Cardiology, All India Institute of Medical Sciences, New Delhi 110029 (India); Vani, V. C. [Department of Instrumentation and Applied Physics, Indian Institute of Science, Bangalore 560012 (India); Lakshmi, R.; Kumar, Pratik, E-mail: drpratikkumar@gmail.com [Department of Cardiac-Biochemistry, All India Institute of Medical Sciences, New Delhi 110029 (India); Mandal, Susama R. [Department of Medical Physics Unit IRCH, All India Institute of Medical Sciences, New Delhi 110029 (India)

    2015-10-15

    Purpose: Composition of the coronary artery plaque is known to have critical role in heart attack. While calcified plaque can easily be diagnosed by conventional CT, it fails to distinguish between fibrous and lipid rich plaques. In the present paper, the authors discuss the experimental techniques and obtain a numerical algorithm by which the electron density (ρ{sub e}) and the effective atomic number (Z{sub eff}) can be obtained from the dual energy computed tomography (DECT) data. The idea is to use this inversion method to characterize and distinguish between the lipid and fibrous coronary artery plaques. Methods: For the purpose of calibration of the CT machine, the authors prepare aqueous samples whose calculated values of (ρ{sub e}, Z{sub eff}) lie in the range of (2.65 × 10{sup 23} ≤ ρ{sub e} ≤ 3.64 × 10{sup 23}/cm{sup 3}) and (6.80 ≤ Z{sub eff} ≤ 8.90). The authors fill the phantom with these known samples and experimentally determine HU(V{sub 1}) and HU(V{sub 2}), with V{sub 1},V{sub 2} = 100 and 140 kVp, for the same pixels and thus determine the coefficients of inversion that allow us to determine (ρ{sub e}, Z{sub eff}) from the DECT data. The HU(100) and HU(140) for the coronary artery plaque are obtained by filling the channel of the coronary artery with a viscous solution of methyl cellulose in water, containing 2% contrast. These (ρ{sub e}, Z{sub eff}) values of the coronary artery plaque are used for their characterization on the basis of theoretical models of atomic compositions of the plaque materials. These results are compared with histopathological report. Results: The authors find that the calibration gives ρ{sub e} with an accuracy of ±3.5% while Z{sub eff} is found within ±1% of the actual value, the confidence being 95%. The HU(100) and HU(140) are found to be considerably different for the same plaque at the same position and there is a linear trend between these two HU values. It is noted that pure lipid type plaques

  16. Approach To Unstable Plaque In Carotid Disease

    Directory of Open Access Journals (Sweden)

    Mojdeh Ghabaee

    2017-02-01

    Full Text Available Risk of cerebral infarction due to thrombo emboli originating  from carotid artery disease estimated to be near 15%, and this risk  is closely associated with the severity of luminal stenosis. But at the same time characteristics  of the plaque should be taken into account for therapeutic planning when the patient is asymptomatic and the diameter of the stenosis does not reach the threshold of 70%. Search for markers of plaque vulnerability, instability, or thromboembolic potential as complementary to the degree of the luminal stenosis in stroke risk prediction should be considered .These morphologic features of carotid plaques are increasingly believed to be one of those markers that could carry further prognostic information, and early recognition of these plaques features may identify a high-risk subgroup of patients who might particularly benefit from aggressive interventions with aggressive medical treatment. Color and duplex Doppler sonography  evaluates both  morphologic and hemodynamic   abnormalitie of carotid. Echogensity, degree of stenosis and plaque surface features are essential parameters of morphological abnormality.

  17. Assessment of vulnerable plaque composition by matching the deformation of a parametric plaque model to measured plaque deformation.

    Science.gov (United States)

    Baldewsing, Radj A; Schaar, Johannes A; Mastik, Frits; Oomens, Cees W J; van der Steen, Antonius F W

    2005-04-01

    Intravascular ultrasound (IVUS) elastography visualizes local radial strain of arteries in so-called elastograms to detect rupture-prone plaques. However, due to the unknown arterial stress distribution these elastograms cannot be directly interpreted as a morphology and material composition image. To overcome this limitation we have developed a method that reconstructs a Young's modulus image from an elastogram. This method is especially suited for thin-cap fibroatheromas (TCFAs), i.e., plaques with a media region containing a lipid pool covered by a cap. Reconstruction is done by a minimization algorithm that matches the strain image output, calculated with a parametric finite element model (PFEM) representation of a TCFA, to an elastogram by iteratively updating the PFEM geometry and material parameters. These geometry parameters delineate the TCFA media, lipid pool and cap regions by circles. The material parameter for each region is a Young's modulus, EM, EL, and EC, respectively. The method was successfully tested on computer-simulated TCFAs (n = 2), one defined by circles, the other by tracing TCFA histology, and additionally on a physical phantom (n = 1) having a stiff wall (measured EM = 16.8 kPa) with an eccentric soft region (measured EL = 4.2 kPa). Finally, it was applied on human coronary plaques in vitro (n = 1) and in vivo (n = 1). The corresponding simulated and measured elastograms of these plaques showed radial strain values from 0% up to 2% at a pressure differential of 20, 20, 1, 20, and 1 mmHg respectively. The used/reconstructed Young's moduli [kPa] were for the circular plaque EL = 50/66, EM = 1500/1484, EC = 2000/2047, for the traced plaque EL = 25/1, EM = 1000/1148, EC = 1500/1491, for the phantom EL = 4.2/4 kPa, EM = 16.8/16, for the in vitro plaque EL = n.a./29, EM = n.a./647, EC = n.a./1784 kPa and for the in vivo plaque EL = n.a./2, EM = n.a./188, Ec = n.a./188 kPa.

  18. Relationship between structural brainstem and brain plasticity and lower-limb training in spinal cord injury: a longitudinal pilot study

    Directory of Open Access Journals (Sweden)

    Michael eVilliger

    2015-05-01

    Full Text Available Rehabilitative training has shown to improve significantly motor outcomes and functional walking capacity in patients with incomplete spinal cord injury (iSCI. However, whether performance improvements during rehabilitation relate to brain plasticity or whether it is based on functional adaptation of movement strategies remain uncertain. This study assessed training improvement-induced structural brain plasticity in chronic iSCI patients using longitudinal MRI.We used tensor-based morphometry (TBM to analyze longitudinal brain volume changes associated with intensive virtual reality (VR-augmented lower limb training in nine traumatic iSCI patients. The MRI data was acquired before and after a 4-week training period (16-20 training sessions. Before training, voxel-based morphometry (VBM and voxel-based cortical thickness (VBCT assessed baseline morphometric differences in nine iSCI patients compared to 14 healthy controls. The intense VR-augmented training of limb control improved significantly balance, walking speed, ambulation, and muscle strength in patients. Retention of clinical improvements was confirmed by the 3-4 months follow-up. In patients relative to controls, reductions in VBM of white matter volume within the brainstem and cerebellum and VBCT showed cortical thinning in the primary motor cortex. Over time, TBM revealed significant improvement-induced increases in the left middle temporal and occipital gyrus, left temporal pole and fusiform gyrus, both hippocampi, cerebellum, corpus callosum, and brainstem in iSCI patients. This study demonstrates structural plasticity at the cortical and brainstem level as a consequence of VR-augmented training in iSCI patients. These structural changes may serve as neuroimaging biomarkers of VR-augmented lower limb neurorehabilitation in addition to performance measures to detect improvements in rehabilitative training.

  19. Evidence that BDNF regulates heart rate by a mechanism involving increased brainstem parasympathetic neuron excitability

    OpenAIRE

    Wan, Ruiqian; Weigand, Letitia A.; Bateman, Ryan; Griffioen, Kathleen; Mendelowitz, David; Mattson, Mark P.

    2014-01-01

    Autonomic control of heart rate is mediated by cardioinhibitory parasympathetic cholinergic neurons located in the brainstem and stimulatory sympathetic noradrenergic neurons. During embryonic development the survival and cholinergic phenotype of brainstem autonomic neurons is promoted by brain-derived neurotrophic factor (BDNF). We now provide evidence that BDNF regulates heart rate by a mechanism involving increased brainstem cardioinhibitory parasympathetic activity. Mice with a BDNF haplo...

  20. Intrinsic brainstem schwannoma – A rare clinical entity and a histological enigma

    Directory of Open Access Journals (Sweden)

    Anil Kumar Sharma

    2016-01-01

    Full Text Available Intraparenchymal schwannomas arising in the brainstem are very rare, and only eight cases have been reported in literature till now. We report an intraparenchymal brainstem schwannoma presenting with the classical clinical presentation of an intrinsic brainstem lesion, and discuss its clinicoradiological characteristics and histological origins. We highlight the importance of an intraoperative frozen section diagnosis in such cases. Intraoperative tissue diagnosis significantly may alter the surgical strategy, which should be aimed at near total intracapsular decompression of the schwannoma.

  1. Cobalt60 plaques in recurrent retinoblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Fass, D.; McCormick, B.; Abramson, D.; Ellsworth, R. (Department of Radiation Oncology, Memorial Sloan-Kettering Cancer Center, NY, NY (USA))

    1991-08-01

    Cobalt60 plaque irradiation is one treatment option for patients with recurrent retinoblastoma following conventional external beam irradiation (ERT). Tumorocidal doses can be delivered without excessive risk of normal tissue injury. In patients not considered candidates for xenon arc or cryotherapy, 60Co is an alternative to enucleation. Between 1968 and 1987, 85 patients were treated with 60Co plaques, 72 of whom had failed prior ERT. Age at diagnosis ranged from 1 week to 4 years. There are 37 males and 35 females. Seventy-one patients had bilateral disease and one had unilateral. Three patients had both eyes plaqued. Prior ERT ranged from 30 to 70 Gy (mean 4200 Gy). Time from initial therapy to failure ranged from 13 to 60 months. Cobalt plaques of 10 mm, 15 mm, or 10 {times} 15 mm were used depending on tumor size and location. Dose prescribed to the apex of the tumor ranged from 30 to 50 Gy (median 40 Gy) given over 3 to 8 days. Twelve patients had two plaque applications; three patients had three plaque applications. All patients were followed with routine ophthalmoscopic examinations. Follow-up ranged from 2 to 22 years (mean 8.7). Seven patients died of metastatic disease; 10 patients developed non-ocular second tumors. Thirty patients required enucleation. Twenty-two patients had clear tumor progression, two patients had radiation complications, and six patients had a combination of tumor growth and complications. Cobalt60 can salvage eyes in retinoblastoma patients failing ERT. Currently, the authors are using I125 in an attempt to spare normal ocular tissue and reduce subsequent complications.

  2. Cobalt60 plaques in recurrent retinoblastoma

    International Nuclear Information System (INIS)

    Fass, D.; McCormick, B.; Abramson, D.; Ellsworth, R.

    1991-01-01

    Cobalt60 plaque irradiation is one treatment option for patients with recurrent retinoblastoma following conventional external beam irradiation (ERT). Tumorocidal doses can be delivered without excessive risk of normal tissue injury. In patients not considered candidates for xenon arc or cryotherapy, 60Co is an alternative to enucleation. Between 1968 and 1987, 85 patients were treated with 60Co plaques, 72 of whom had failed prior ERT. Age at diagnosis ranged from 1 week to 4 years. There are 37 males and 35 females. Seventy-one patients had bilateral disease and one had unilateral. Three patients had both eyes plaqued. Prior ERT ranged from 30 to 70 Gy (mean 4200 Gy). Time from initial therapy to failure ranged from 13 to 60 months. Cobalt plaques of 10 mm, 15 mm, or 10 x 15 mm were used depending on tumor size and location. Dose prescribed to the apex of the tumor ranged from 30 to 50 Gy (median 40 Gy) given over 3 to 8 days. Twelve patients had two plaque applications; three patients had three plaque applications. All patients were followed with routine ophthalmoscopic examinations. Follow-up ranged from 2 to 22 years (mean 8.7). Seven patients died of metastatic disease; 10 patients developed non-ocular second tumors. Thirty patients required enucleation. Twenty-two patients had clear tumor progression, two patients had radiation complications, and six patients had a combination of tumor growth and complications. Cobalt60 can salvage eyes in retinoblastoma patients failing ERT. Currently, the authors are using I125 in an attempt to spare normal ocular tissue and reduce subsequent complications

  3. A modified COMS plaque for iris melanoma

    Directory of Open Access Journals (Sweden)

    Daniel J. Scanderbeg

    2011-09-01

    Full Text Available Melanoma of the iris is a rare condition compared to posterior ocular tumors and in this case report we presenta 51-year-old female patient with diffuse iris melanoma. Traditional COMS (Collaborative Ocular Melanoma Studyplaques are used at our institution for radiation therapy, so a novel modification of the traditional plaque was requiredto allow better conformance with placement on the cornea. The usual silastic insert was machined to dimensions incompliance with the cornea, placed without incident, and treatment delivered with excellent patient tolerance of themodified plaque.

  4. Atherosclerotic plaque rupture and thrombosis. Evolving concepts.

    Science.gov (United States)

    Fuster, V; Stein, B; Ambrose, J A; Badimon, L; Badimon, J J; Chesebro, J H

    1990-09-01

    Rupture of an atherosclerotic plaque associated with partial or complete thrombotic vessel occlusion is fundamental to the development of ischemic coronary syndromes. Plaques that produce only mild-to-moderate angiographic luminal stenosis are frequently those that undergo abrupt disruption, leading to unstable angina or acute myocardial infarction. Plaques with increased lipid content appear more prone to rupture, particularly when the lipid pool is localized eccentrically within the intima. Macrophages appear to play an important role in atherogenesis, perhaps by participating in the uptake and metabolism of lipoproteins, secretion of growth factors, and production of enzymes and toxic metabolites that may facilitate plaque rupture. In addition, the particular composition or configuration of a plaque and the hemodynamic forces to which it is exposed may determine its susceptibility to disruption. Exposure of collagen, lipids, and smooth muscle cells after plaque rupture leads to the activation of platelets and the coagulation cascade system. The resulting thrombus may lead to marked reduction in myocardial perfusion and the development of an unstable coronary syndrome, or it may become organized and incorporated into the diseased vessel, thus contributing to the progression of atherosclerosis. In unstable angina, plaque disruption leads to thrombosis, which is usually labile and results in only a transient reduction in myocardial perfusion. Release of vasoactive substances, arterial spasm, or increases in myocardial oxygen demand may contribute to ischemia. In acute myocardial infarction, plaque disruption results in a more persistent thrombotic vessel occlusion; the extent of necrosis depends on the size of the artery, the duration of occlusion, the presence of collateral flow, and the integrity of the fibrinolytic system. Thrombi that undergo lysis expose a highly thrombogenic surface to the circulating blood, which has the capacity of activating platelets and

  5. Herpes simplex encephalitis with thalamic, brainstem and cerebellar involvement.

    Science.gov (United States)

    Garg, Meenal; Kulkarni, Shilpa; Udwadia Hegde, Anaita

    2018-04-01

    Herpes simplex virus encephalitis is a common and treatable cause of acute encephalitis in all age groups. Certain radiological features such as temporal parenchymal involvement facilitate the diagnosis. The use of herpes simplex virus polymerase chain reaction has expanded the clinical and imaging spectrum. We report the case of a young patient who presented with a movement disorder and predominant involvement of thalami, brainstem and cerebellum on magnetic resonance imaging, and was diagnosed with herpes simplex virus encephalitis. Differentiation from Japanese encephalitis may be difficult in these patients, especially in endemic areas, and may necessitate the use of relevant investigations in all patients.

  6. Descending Command Neurons in the Brainstem that Halt Locomotion

    DEFF Research Database (Denmark)

    Bouvier, Julien; Caggiano, Vittorio; Leiras, Roberto

    2015-01-01

    identifiable brainstem populations to a potential locomotor stop signal, we used developmental genetics and considered a discrete neuronal population in the reticular formation: the V2a neurons. We find that those neurons constitute a major excitatory pathway to locomotor areas of the ventral spinal cord....... Selective activation of V2a neurons of the rostral medulla stops ongoing locomotor activity, owing to an inhibition of premotor locomotor networks in the spinal cord. Moreover, inactivation of such neurons decreases spontaneous stopping in vivo. Therefore, the V2a "stop neurons" represent a glutamatergic...

  7. Brainstem and limbic encephalitis with paraneoplastic neuromyelitis optica.

    Science.gov (United States)

    Moussawi, Khaled; Lin, David J; Matiello, Marcelo; Chew, Sheena; Morganstern, Daniel; Vaitkevicius, Henrikas

    2016-01-01

    The spectrum of disorders associated with anti-neuromyelitis optica (NMO) antibody is being extended to include infrequent instances associated with cancer. We describe a patient with brainstem and limbic encephalitis from NMO-immunoglobulin G in serum and cerebrospinal fluid in the context of newly diagnosed breast cancer. The neurological features markedly improved with excision of her breast cancer and immune suppressive therapy. This case further broadens the NMO spectrum disorders (NMOSD) by an association between NMOSD and cancer and raises the question of coincidental occurrence and the appropriate circumstances to search for a tumor in certain instances of NMO. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Plaque retention on elastomeric ligatures. An in vivo study

    OpenAIRE

    CONDÒ, R.; CASAGLIA, A.; CONDÒ, S.G.; CERRONI, L.

    2013-01-01

    Fixed orthodontic appliances make it difficult to maintain the oral hygiene, resulting in plaque accumulation. Retention of bacterial plaque, represents a risk for white spot lesions and development of periodontal disease.

  9. Coronary CT Angiography in the Quantitative Assessment of Coronary Plaques

    Directory of Open Access Journals (Sweden)

    Zhonghua Sun

    2014-01-01

    Full Text Available Coronary computed tomography angiography (CCTA has been recently evaluated for its ability to assess coronary plaque characteristics, including plaque composition. Identification of the relationship between plaque composition by CCTA and patient clinical presentations may provide insight into the pathophysiology of coronary artery plaque, thus assisting identification of vulnerable plaques which are associated with the development of acute coronary syndrome. CCTA-generated 3D visualizations allow evaluation of both coronary lesions and lumen changes, which are considered to enhance the diagnostic performance of CCTA. The purpose of this review is to discuss the recent developments that have occurred in the field of CCTA with regard to its diagnostic accuracy in the quantitative assessment of coronary plaques, with a focus on the characterization of plaque components and identification of vulnerable plaques.

  10. Linear accelerator-based stereotactic radiosurgery for brainstem metastases: the Dana-Farber/Brigham and Women's Cancer Center experience.

    Science.gov (United States)

    Kelly, Paul J; Lin, Yijie Brittany; Yu, Alvin Y C; Ropper, Alexander E; Nguyen, Paul L; Marcus, Karen J; Hacker, Fred L; Weiss, Stephanie E

    2011-09-01

    To review the safety and efficacy of linear accelerator-based stereotactic radiosurgery (SRS) for brainstem metastases. We reviewed all patients with brain metastases treated with SRS at DF/BWCC from 2001 to 2009 to identify patients who had SRS to a single brainstem metastasis. Overall survival and freedom-from-local failure rates were calculated from the date of SRS using the Kaplan-Meier method. Prognostic factors were evaluated using the log-rank test and Cox proportional hazards model. A total of 24 consecutive patients with brainstem metastases had SRS. At the time of SRS, 21/24 had metastatic lesions elsewhere within the brain. 23/24 had undergone prior WBRT. Primary diagnoses included eight NSCLC, eight breast cancer, three melanoma, three renal cell carcinoma and two others. Median dose was 13 Gy (range, 8-16). One patient had fractionated SRS 5 Gy ×5. Median target volume was 0.2 cc (range, 0.02-2.39). The median age was 57 years (range, 42-92). Follow-up information was available in 22/24 cases. At the time of analysis, 18/22 patients (82%) had died. The median overall survival time was 5.3 months (range, 0.8-21.1 months). The only prognostic factor that trended toward statistical significance for overall survival was the absence of synchronous brain metastasis at the time of SRS; 1-year overall survival was 31% with versus 67% without synchronous brain metastasis (log rank P = 0.11). Non-significant factors included primary tumor histology and status of extracranial disease (progressing vs. stable/absent). Local failure occurred in 4/22 cases (18%). Actuarial freedom from local failure for all cases was 78.6% at 1 year. RTOG grade 3 toxicities were recorded in two patients (ataxia, confusion). Linac-based SRS for small volume brainstem metastases using a median dose of 13 Gy is associated with acceptable local control and low morbidity.

  11. Volumetric analysis of coronary plaque characterization in patients with metabolic syndrome using 64-slice multi-detector computed tomography

    International Nuclear Information System (INIS)

    Arai, Kosuke; Ishii, Hideki; Amano, Tetasuya

    2010-01-01

    Metabolic syndrome (MetS) is associated with adverse cardiovascular events and mortality, where acute coronary syndrome significantly impacts on mortality and morbidity. In contrast, evidences have accumulated that the lipid-rich plaque might play a critical role in acute coronary syndrome. The study population consisted of 94 patients with suspected angina pectoris who underwent multi-detector computed tomography (MDCT). Of those, we identified 41 with MetS. In MDCT analysis, low-density plaque volume (LDPV) (42±28 vs 24±18 mm 3 , P=0.0003), moderate-density plaque volume (105±41 vs 82±33 mm(3), P=0.003), total plaque volume (164±70 vs 118±59 mm 3 ), P=0.0008) and %LDPV (24.2±10.0 vs 18.3±7.1%, P=0.01) were significantly increased in the MetS group compared to the non-MetS group. Multivariate linear regression analysis after adjusting for confounding variables revealed that MetS was significantly correlated with an increase in %LDPV (β=0.48, P=0.0001). Multivariate logistic regression analysis for lipid-rich plaque after adjusting for confounding variables indicated that MetS was significantly associated with lipid-rich plaque (odds ratio: 5.99, 95% confidence intervals: 1.94-18.6, P=0.002). Patients with MetS were strongly related to having a lipid-rich composition in their coronary plaque, as detected by MDCT. (author)

  12. Vascular Plaque Determination for Stroke Risk Assessment

    Science.gov (United States)

    2017-10-01

    accident, carotid endarterectomy, ultrasound, spectral analysis, tissue characterization, machine learning , noninvasive, carotid plaque 16. SECURITY...stroke, cerebrovascular accident, carotid endarterectomy, ultrasound, spectral analysis, tissue characterization, machine learning , noninvasive...Introduction 4 2. Keywords 4 3. Accomplishments 4 4. Impact 9 5. Changes/Problems 10 6. Products 11 7. Participants & Other Collaborating

  13. Plaque rupture in humans and mice

    DEFF Research Database (Denmark)

    Schwartz, Stephen M; Galis, Zorina S; Rosenfeld, Michael E

    2007-01-01

    Despite the many studies of murine atherosclerosis, we do not yet know the relevance of the natural history of this model to the final events precipitated by plaque disruption of human atherosclerotic lesions. The literature has become particularly confused because of the common use of terms such...

  14. Detection and segmentation of virus plaque using HOG and SVM: toward automatic plaque assay.

    Science.gov (United States)

    Mao, Yihao; Liu, Hong; Ye, Rong; Shi, Yonghong; Song, Zhijian

    2014-01-01

    Plaque assaying, measurement of the number, diameter, and area of plaques in a Petri dish image, is a standard procedure gauging the concentration of phage in biology. This paper presented a novel and effective method for implementing automatic plaque assaying. The method was mainly comprised of the following steps: In the training stage, after pre-processing the images for noise suppression, an initial training set was readied by sampling positive (with a plaque at the center) and negative (plaque-free) patches from the training images, and extracting the HOG features from each patch. The linear SVM classifier was trained in a self-learnt supervised learning strategy to avoid possible missing detection. Specifically, the training set which contained positive and negative patches sampled manually from training images was used to train the preliminary classifier which exhaustively searched the training images to predict the label for the unlabeled patches. The mislabeled patches were evaluated by experts and relabeled. And all the newly labeled patches and their corresponding HOG features were added to the initial training set to train the final classifier. In the testing stage, a sliding-window technique was first applied to the unseen image for obtaining HOG features, which were inputted into the classifier to predict whether the patch was positive. Second, a locally adaptive Otsu method was performed on the positive patches to segment the plaques. Finally, after removing the outliers, the parameters of the plaques were measured in the segmented plaques. The experimental results demonstrated that the accuracy of the proposed method was similar to the one measured manually by experts, but it took less than 30 seconds.

  15. Brain-stem evoked potentials and noise effects in seagulls.

    Science.gov (United States)

    Counter, S A

    1985-01-01

    Brain-stem auditory evoked potentials (BAEP) recorded from the seagull were large-amplitude, short-latency, vertex-positive deflections which originate in the eighth nerve and several brain-stem nuclei. BAEP waveforms were similar in latency and configurations to that reported for certain other lower vertebrates and some mammals. BAEP recorded at several pure tone frequencies throughout the seagull's auditory spectrum showed an area of heightened auditory sensitivity between 1 and 3 kHz. This range was also found to be the primary bandwidth of the vocalization output of young seagulls. Masking by white noise and pure tones had remarkable effects on several parameters of the BAEP. In general, the tone- and click-induced BAEP were either reduced or obliterated by both pure tone and white noise maskers of specific signal to noise ratios and high intensity levels. The masking effects observed in this study may be related to the manner in which seagulls respond to intense environmental noise. One possible conclusion is that intense environmental noise, such as aircraft engine noise, may severely alter the seagull's localization apparatus and induce sonogenic stress, both of which could cause collisions with low-flying aircraft.

  16. Dopamine and the Brainstem Locomotor Networks: From Lamprey to Human

    Directory of Open Access Journals (Sweden)

    Dimitri Ryczko

    2017-05-01

    Full Text Available In vertebrates, dopamine neurons are classically known to modulate locomotion via their ascending projections to the basal ganglia that project to brainstem locomotor networks. An increased dopaminergic tone is associated with increase in locomotor activity. In pathological conditions where dopamine cells are lost, such as in Parkinson's disease, locomotor deficits are traditionally associated with the reduced ascending dopaminergic input to the basal ganglia. However, a descending dopaminergic pathway originating from the substantia nigra pars compacta was recently discovered. It innervates the mesencephalic locomotor region (MLR from basal vertebrates to mammals. This pathway was shown to increase locomotor output in lampreys, and could very well play an important role in mammals. Here, we provide a detailed account on the newly found dopaminergic pathway in lamprey, salamander, rat, monkey, and human. In lampreys and salamanders, dopamine release in the MLR is associated with the activation of reticulospinal neurons that carry the locomotor command to the spinal cord. Dopamine release in the MLR potentiates locomotor movements through a D1-receptor mechanism in lampreys. In rats, stimulation of the substantia nigra pars compacta elicited dopamine release in the pedunculopontine nucleus, a known part of the MLR. In a monkey model of Parkinson's disease, a reduced dopaminergic innervation of the brainstem locomotor networks was reported. Dopaminergic fibers are also present in human pedunculopontine nucleus. We discuss the conserved locomotor role of this pathway from lamprey to mammals, and the hypothesis that this pathway could play a role in the locomotor deficits reported in Parkinson's disease.

  17. Brainstem encephalitis and acute polyneuropathy associated with hepatitis E infection.

    Science.gov (United States)

    Salim, Omar Jabbar; Davidson, Amy; Li, Kathy; Leach, John Paul; Heath, Craig

    2017-09-11

    A 59-year-old man presented with feverish illness. His Glasgow Coma Scale was 15, had reduced visual acuity in the left eye with partial left ptosis and mild left hemiparesis with an extensor left plantar. Over 48 hours, he accrued multiple cranial nerves palsies and progressed to a flaccid paralysis necessitating admission to an intensive care unit.Cerebrospinal fluid (CSF) study showed 20 lymphocytes and raised protein. Viral and bacterial PCRs were negative. Samples for Lyme, blood-borne viruses, syphilis and autoantibodies were also negative. MRI brain showed T2 abnormalities within the brainstem. Nerve conduction studies revealed an acute motor and sensory axonal neuropathy pattern of Guillian Barre Syndrome (GBS). The patient was treated for both infective and inflammatory causes of brainstem encephalitis and GBS.Retrospective studies confirmed the presence of hepatitis E virus (HEV) RNA in CSF and serum studies showed positive HEV IgG and IgM prior to intravenous infusion. After 3 months of intensive rehabilitation, the patient was discharged home walking with a frame. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. Development of Brainstem-Evoked Responses in Congenital Auditory Deprivation

    Directory of Open Access Journals (Sweden)

    J. Tillein

    2012-01-01

    Full Text Available To compare the development of the auditory system in hearing and completely acoustically deprived animals, naive congenitally deaf white cats (CDCs and hearing controls (HCs were investigated at different developmental stages from birth till adulthood. The CDCs had no hearing experience before the acute experiment. In both groups of animals, responses to cochlear implant stimulation were acutely assessed. Electrically evoked auditory brainstem responses (E-ABRs were recorded with monopolar stimulation at different current levels. CDCs demonstrated extensive development of E-ABRs, from first signs of responses at postnatal (p.n. day 3 through appearance of all waves of brainstem response at day 8 p.n. to mature responses around day 90 p.n.. Wave I of E-ABRs could not be distinguished from the artifact in majority of CDCs, whereas in HCs, it was clearly separated from the stimulus artifact. Waves II, III, and IV demonstrated higher thresholds in CDCs, whereas this difference was not found for wave V. Amplitudes of wave III were significantly higher in HCs, whereas wave V amplitudes were significantly higher in CDCs. No differences in latencies were observed between the animal groups. These data demonstrate significant postnatal subcortical development in absence of hearing, and also divergent effects of deafness on early waves II–IV and wave V of the E-ABR.

  19. An autopsied case of MV2K + C-type sporadic Creutzfeldt-Jakob disease presenting with widespread cerebral cortical involvement and Kuru plaques.

    Science.gov (United States)

    Iwasaki, Yasushi; Saito, Yufuko; Aiba, Ikuko; Kobayashi, Atsushi; Mimuro, Maya; Kitamoto, Tetsuyuki; Yoshida, Mari

    2017-06-01

    MV2-type sporadic Creutzfeldt-Jakob disease (sCJD), which was previously called "Kuru-plaque variant", was gradually revealed to have a wide spectrum and has been classified into three pathological subtypes: MV2K, MV2C and MV2K + C. We herein describe the detailed clinical findings and neuropathologic observations from an autopsied MV2K + C-type Japanese sCJD case with widespread cerebral cortical pathology and Kuru plaques. In the early stages of the disease, the patient exhibited gait disturbance with ataxia and dysarthria as well as gradual appearance of cognitive dysfunction. Diffusion-weighted images (DWI) on MRI revealed extensive cerebral cortical hyperintensity. Pathologic investigation revealed extensive spongiform change in the cerebral cortex, particularly in the deeper layers. Vacuole size varied, and some were confluent. Prion protein (PrP) immunostaining revealed extensive PrP deposition in the cerebral cortex, basal ganglia, thalamus, cerebellum, brainstem and spinal cord. In the cerebral cortex, synaptic-type, Kuru plaque-like, and coarse plaque-type PrP depositions were mainly observed, along with some perivacuolar-type PrP depositions. Kuru plaques and coarse plaque-type PrP depositions also were observed in the cerebellar cortex. PrP gene analysis revealed no mutations, and polymorphic codon 129 exhibited Met/Val heterozygosity. Western blot analysis revealed a mixture of intermediate-type PrP Sc and type 2 PrP Sc . Based on previous reports regarding MV2-type sCJD and the clinicopathologic findings of the present case, we speculated that it may be possible to clinically distinguish each MV2 subtype. Clinical presentation of the MV2K + C subtype includes predominant cerebral cortical involvement signs with ataxia and DWI hyperintensity of the cerebral cortex on MRI. © 2016 Japanese Society of Neuropathology.

  20. Fluorescence immunoassay for detecting periodontal bacterial pathogens in plaque.

    OpenAIRE

    Wolff, L F; Anderson, L; Sandberg, G P; Aeppli, D M; Shelburne, C E

    1991-01-01

    A particle concentration fluorescence immunoassay has been modified into a bacterial concentration fluorescence immunoassay (BCFIA) to rapidly detect periodontopathic bacteria in human plaque samples. The BCFIA utilizes fluorescently tagged monoclonal antibodies (MAbs) directed against the lipopolysaccharide of selected gram-negative plaque bacteria. Microorganisms closely associated with periodontal disease that can be identified in plaque with the BCFIA include Porphyromonas gingivalis, Bac...

  1. [Evaluation of dental plaque by quantitative digital image analysis system].

    Science.gov (United States)

    Huang, Z; Luan, Q X

    2016-04-18

    To analyze the plaque staining image by using image analysis software, to verify the maneuverability, practicability and repeatability of this technique, and to evaluate the influence of different plaque stains. In the study, 30 volunteers were enrolled from the new dental students of Peking University Health Science Center in accordance with the inclusion criteria. The digital images of the anterior teeth were acquired after plaque stained according to filming standardization.The image analysis was performed using Image Pro Plus 7.0, and the Quigley-Hein plaque indexes of the anterior teeth were evaluated. The plaque stain area percentage and the corresponding dental plaque index were highly correlated,and the Spearman correlation coefficient was 0.776 (Pchart showed only a few spots outside the 95% consistency boundaries. The different plaque stains image analysis results showed that the difference of the tooth area measurements was not significant, while the difference of the plaque area measurements significant (P<0.01). This method is easy in operation and control,highly related to the calculated percentage of plaque area and traditional plaque index, and has good reproducibility.The different plaque staining method has little effect on image segmentation results.The sensitive plaque stain for image analysis is suggested.

  2. Three-dimensional carotid ultrasound plaque texture predicts vascular events

    DEFF Research Database (Denmark)

    van Engelen, Arna; Wannarong, Thapat; Parraga, Grace

    2014-01-01

    BACKGROUND AND PURPOSE: Carotid ultrasound atherosclerosis measurements, including those of the arterial wall and plaque, provide a way to monitor patients at risk of vascular events. Our objective was to examine carotid ultrasound plaque texture measurements and the change in carotid plaque text...

  3. Tensile and compressive properties of fresh human carotid atherosclerotic plaques.

    LENUS (Irish Health Repository)

    Maher, Eoghan

    2009-12-11

    Accurate characterisation of the mechanical properties of human atherosclerotic plaque is important for our understanding of the role of vascular mechanics in the development and treatment of atherosclerosis. The majority of previous studies investigating the mechanical properties of human plaque are based on tests of plaque tissue removed following autopsy. This study aims to characterise the mechanical behaviour of fresh human carotid plaques removed during endarterectomy and tested within 2h. A total of 50 radial compressive and 17 circumferential tensile uniaxial tests were performed on samples taken from 14 carotid plaques. The clinical classification of each plaque, as determined by duplex ultrasound is also reported. Plaques were classified as calcified, mixed or echolucent. Experimental data indicated that plaques were highly inhomogeneous; with variations seen in the mechanical properties of plaque obtained from individual donors and between donors. The mean behaviour of samples for each classification indicated that calcified plaques had the stiffest response, while echolucent plaques were the least stiff. Results also indicated that there may be a difference in behaviour of samples taken from different anatomical locations (common, internal and external carotid), however the large variability indicates that more testing is needed to reach significant conclusions. This work represents a step towards a better understanding of the in vivo mechanical behaviour of human atherosclerotic plaque.

  4. Plaque reduction over time of an integrated oral hygiene system.

    Science.gov (United States)

    Nunn, Martha E; Ruhlman, C Douglas; Mallatt, Philip R; Rodriguez, Sally M; Ortblad, Katherine M

    2004-10-01

    This article compares the efficacy of a prototype integrated system (the IntelliClean System from Sonicare and Crest) in the reduction of supragingival plaque to that of a manual toothbrush and conventional toothpaste. The integrated system was compared to a manual toothbrush with conventional toothpaste in a randomized, single-blinded, parallel, 4-week, controlled clinical trial with 100 subjects randomized to each treatment group. There was a low dropout rate, with 89 subjects in the manual toothbrush group (11% loss to follow-up) and 93 subjects in the integrated system group (7% loss to follow-up) completing the study. The Turesky modification of the Quigley and Hein Plaque Index was used to assess full-mouth plaque scores for each subject. Prebrushing plaque scores were obtained at baseline and at 4 weeks after 14 to 20 hours of plaque accumulation. A survey also was conducted at the conclusion of the study to determine the attitude toward the two oral hygiene systems. The integrated system was found to significantly reduce overall and interproximal prebrushing plaque scores over 4 weeks, both by 8.6%, demonstrating statistically significant superiority in overall plaque reduction (P = .002) and interproximal plaque reduction (P < .001) compared to the manual toothbrush with conventional toothpaste, which showed no significant reduction in either overall plaque or interproximal plaque. This study demonstrates that the IntelliClean System from Sonicare and Crest is superior to a manual toothbrush with conventional toothpaste in reducing overall plaque and interproximal plaque over time.

  5. Initial stress in biomechanical models of atherosclerotic plaques

    NARCIS (Netherlands)

    Speelman, L.; Akyildiz, A.C.; Adel, den B.; Wentzel, J.J.; Steen, van der A.F.W.; Virmani, R.; Weerd, van der L.; Jukema, J.W.; Poelmann, R.E.; Brummelen, van E.H.; Gijsen, F.J.H.

    2011-01-01

    Rupture of atherosclerotic plaques is the underlying cause for the majority of acute strokes and myocardial infarctions. Rupture of the plaque occurs when the stress in the plaque exceeds the strength of the material locally. Biomechanical stress analyses are commonly based on pressurized

  6. 3D Fiber Orientation in Atherosclerotic Carotid Plaques

    NARCIS (Netherlands)

    A.C. Akyildiz (Ali); C.-K. Chai (Chen-Ket); C.W.J. Oomens (Cees); A. van der Lugt (Aad); F.P.T. Baaijens (Frank); G.J. Strijkers (Gustav); F.J.H. Gijsen (Frank)

    2017-01-01

    textabstractAtherosclerotic plaque rupture is the primary trigger of fatal cardiovascular events. Fibrillar collagen in atherosclerotic plaques and their directionality are anticipated to play a crucial role in plaque rupture. This study aimed assessing 3D fiber orientations and architecture in

  7. A new strategic neurosurgical planning tool for brainstem cavernous malformations using interactive computer graphics with multimodal fusion images.

    Science.gov (United States)

    Kin, Taichi; Nakatomi, Hirofumi; Shojima, Masaaki; Tanaka, Minoru; Ino, Kenji; Mori, Harushi; Kunimatsu, Akira; Oyama, Hiroshi; Saito, Nobuhito

    2012-07-01

    In this study, the authors used preoperative simulation employing 3D computer graphics (interactive computer graphics) to fuse all imaging data for brainstem cavernous malformations. The authors evaluated whether interactive computer graphics or 2D imaging correlated better with the actual operative field, particularly in identifying a developmental venous anomaly (DVA). The study population consisted of 10 patients scheduled for surgical treatment of brainstem cavernous malformations. Data from preoperative imaging (MRI, CT, and 3D rotational angiography) were automatically fused using a normalized mutual information method, and then reconstructed by a hybrid method combining surface rendering and volume rendering methods. With surface rendering, multimodality and multithreshold techniques for 1 tissue were applied. The completed interactive computer graphics were used for simulation of surgical approaches and assumed surgical fields. Preoperative diagnostic rates for a DVA associated with brainstem cavernous malformation were compared between conventional 2D imaging and interactive computer graphics employing receiver operating characteristic (ROC) analysis. The time required for reconstruction of 3D images was 3-6 hours for interactive computer graphics. Observation in interactive mode required approximately 15 minutes. Detailed anatomical information for operative procedures, from the craniotomy to microsurgical operations, could be visualized and simulated three-dimensionally as 1 computer graphic using interactive computer graphics. Virtual surgical views were consistent with actual operative views. This technique was very useful for examining various surgical approaches. Mean (±SEM) area under the ROC curve for rate of DVA diagnosis was significantly better for interactive computer graphics (1.000±0.000) than for 2D imaging (0.766±0.091; pcomputer graphics than with 2D images. Interactive computer graphics was also useful in helping to plan the surgical

  8. Topographic association of angioscopic yellow plaques with coronary atherosclerotic plaque: assessment with quantitative colorimetry in human coronary artery autopsy specimens.

    Science.gov (United States)

    Ishibashi, Fumiyuki; Lisauskas, Jennifer B; Kawamura, Akio; Waxman, Sergio

    2008-01-01

    Yellow plaques seen during coronary angioscopy are thought to be the surrogates for superficial intimal lipids in coronary plaque. Given diffuse and heterogeneous nature of atherosclerosis, yellow plaques in coronaries may be seen as several yellow spots on diffuse coronary plaque. We examined the topographic association of yellow plaques with coronary plaque. In 40 non-severely stenotic ex-vivo coronary segments (average length: 52.2 +/- 3.1 mm), yellow plaques were examined by angioscopy with quantitative colorimetry. The segments were cut perpendicular to the long axis of the vessel at 2 mm intervals, and 1045 slides with 5 microm thick tissue for whole segments were prepared. To construct the plaque surface, each tissue slice was considered to be representative of the adjacent 2 mm. The circumference of the lumen and the lumen border of plaque were measured in each slide, and the plaque surface region was constructed. Coronary plaque was in 37 (93%) of 40 segments, and consisted of a single mass [39.9 +/- 3.9 (0-100) mm, 311.3 +/- 47.4 (0.0-1336.2) mm2]. In 30 (75%) segments, multiple (2-9) yellow plaques were detected on a mass of coronary plaque. The number of yellow plaques correlated positively with coronary plaque surface area (r = 0.77, P colorimetry, some of them are associated with lipid cores underneath thin fibrous caps, may be used to assess the extent of coronary plaque. Further research using angioscopy could be of value to study the association of high-risk coronaries with acute coronary syndromes.

  9. Comparison of sensitivity of magnetic resonance imaging and evoked potentials in the detection of brainstem involvement in multiple sclerosis

    International Nuclear Information System (INIS)

    Comi, G.; Martinelli, V.; Medaglini, S.; Locatelli, T.; Magnani, G.; Poggi, A.; Triulzi, F.

    1988-01-01

    A comparison was made of the sensitivity of magnetic resonance imaging and the combined use of Brainstem Auditory Evoked Potential and Median Somatosensory Evoked Potential in the detection of brainstem dysfunction in 54 multiple sclerosis patients. 10 refs.; 2 tabs

  10. The human auditory brainstem response to running speech reveals a subcortical mechanism for selective attention.

    Science.gov (United States)

    Forte, Antonio Elia; Etard, Octave; Reichenbach, Tobias

    2017-10-10

    Humans excel at selectively listening to a target speaker in background noise such as competing voices. While the encoding of speech in the auditory cortex is modulated by selective attention, it remains debated whether such modulation occurs already in subcortical auditory structures. Investigating the contribution of the human brainstem to attention has, in particular, been hindered by the tiny amplitude of the brainstem response. Its measurement normally requires a large number of repetitions of the same short sound stimuli, which may lead to a loss of attention and to neural adaptation. Here we develop a mathematical method to measure the auditory brainstem response to running speech, an acoustic stimulus that does not repeat and that has a high ecological validity. We employ this method to assess the brainstem's activity when a subject listens to one of two competing speakers, and show that the brainstem response is consistently modulated by attention.

  11. Value of the lateral view in diagnosing pleural plaques

    International Nuclear Information System (INIS)

    Hillerdal, G.

    1986-01-01

    To assess the value of the lateral view in the diagnosis of pleural plaques, 2018 chest roentgenograms from the general population were scrutinized for such plaques. The lateral and posterior-anterior (PA) views were read separately and without knowledge of the occupational history or other clinical data. Of the males, 4.8% had pleural plaques in the PA view and 2% had dorsal pleural plaques in the lateral view. A total of 54% of the positive cases in the PA view also showed typical plaques in the PA view. Thus, there remained a number of cases which were diagnosed only in the lateral view; in all, these constituted 18.8%

  12. Carotid artery plaque imaging. Present status and new perspectives

    International Nuclear Information System (INIS)

    Hishikawa, Tomohito; Date, Isao; Iihara, Koji; Yamada, Naoaki; Ueda, Hatsue; Nagatsuka, Kazuyuki; Miyamoto, Susumu

    2010-01-01

    At present, the management of carotid artery (CA) stenosis depends largely on the degree of stenosis. CA plaque imaging is a modality, which assesses the nature of CA plaques objectively and less invasively, that has developed remarkably in recent years. The use of CA plaque imaging in the management of CA stenosis not only reveals the degree of stenosis but it can make the selection of treatment more appropriate by taking the plaque character into consideration. In this manuscript, we introduce ultrasound, intravascular ultrasound, angiography, magnetic resonance imaging (MRI), positron emission tomography (PET) and computed tomography (CT) and describe the present situation and new perspectives of CA plaque imaging. (author)

  13. Tractography of the brainstem in major depressive disorder using diffusion tensor imaging.

    Directory of Open Access Journals (Sweden)

    Yun Ju C Song

    Full Text Available BACKGROUND: The brainstem is the main region that innervates neurotransmitter release to the Hypothalamic-Pituitary Adrenal (HPA axis and fronto-limbic circuits, two key brain circuits found to be dysfunctional in Major Depressive Disorder (MDD. However, the brainstem's role in MDD has only been evaluated in limited reports. Using Diffusion Tensor Imaging (DTI, we investigated whether major brainstem white matter tracts that relate to these two circuits differ in MDD patients compared to healthy controls. METHODS: MDD patients (n = 95 and age- and gender-matched controls (n = 34 were assessed using probabilistic tractography of DTI to delineate three distinct brainstem tracts: the nigrostriatal tract (connecting brainstem to striatum, solitary tract (connecting brainstem to amygdala and corticospinal tract (connecting brainstem to precentral cortex. Fractional anisotropy (FA was used to measure the white matter integrity of these tracts, and measures were compared between MDD and control participants. RESULTS: MDD participants were characterized by a significant and specific decrease in white matter integrity of the right solitary tract (p<0.009 using independent t-test, which is a "bottom up" afferent pathway that connects the brainstem to the amygdala. This decrease was not related to symptom severity. CONCLUSIONS: The results provide new evidence to suggest that structural connectivity between the brainstem and the amygdala is altered in MDD. These results are interesting in light of predominant theories regarding amygdala-mediated emotional reactivity observed in functional imaging studies of MDD. The characterization of altered white matter integrity in the solitary tract in MDD supports the possibility of dysfunctional brainstem-amygdala connectivity impacting vulnerable circuits in MDD.

  14. Assessment of carotid plaque vulnerability using structural and geometrical determinants

    International Nuclear Information System (INIS)

    Li, Z.Y.; Tang, T.; U-King-Im, J.; Graves, M.; Gillard, J.H.; Sutcliffe, M.

    2008-01-01

    Because many acute cerebral ischemic events are caused by rupture of vulnerable carotid atheroma and subsequent thrombosis, the present study used both idealized and patient-specific carotid atheromatous plaque models to evaluate the effect of structural determinants on stress distributions within plaque. Using a finite element method, structural analysis was performed using models derived from in vivo high-resolution magnetic resonance imaging (MRI) of carotid atheroma in 40 non-consecutive patients (20 symptomatic, 20 asymptomatic). Plaque components were modeled as hyper-elastic materials. The effects of varying fibrous cap thickness, lipid core size and lumen curvature on plaque stress distributions were examined. Lumen curvature and fibrous cap thickness were found to be major determinants of plaque stress. The size of the lipid core did not alter plaque stress significantly when the fibrous cap was relatively thick. The correlation between plaque stress and lumen curvature was significant for both symptomatic (p=0.01; correlation coefficient: 0.689) and asymptomatic patients (p=0.01; correlation coefficient: 0.862). Lumen curvature in plaques of symptomatic patients was significantly larger than those of asymptomatic patients (1.50±1.0 mm -1 vs 1.25±0.75 mm -1 ; p=0.01). Specific plaque morphology (large lumen curvature and thin fibrous cap) is closely related to plaque vulnerability. Structural analysis using high-resolution MRI of carotid atheroma may help in detecting vulnerable atheromatous plaque and aid the risk stratification of patients with carotid disease. (author)

  15. 18FDG PET and ultrasound echolucency in carotid artery plaques

    DEFF Research Database (Denmark)

    Graebe, Martin; Pedersen, Sune F; Højgaard, Liselotte

    2010-01-01

    OBJECTIVES: The objective was to evaluate inflammation in echolucent carotid artery plaques. BACKGROUND: Ultrasound echolucency of carotid artery plaques has been proven to differentiate patients at high risk of stroke. On the other hand, positron emission tomography (PET) of plaques with the use...... for ultrasound and PET imaging. Plaque standardized gray scale medians (GSM) were measured in longitudinal ultrasound images to quantitate echolucency, and GSM values were compared with FDG PET uptake quantified by maximum standardized uptake values (SUV). Symptomatic plaques were compared with contralateral...... plaques ranged from high to low inflammatory activity, as depicted with PET. Quantitative FDG SUV differentiated asymptomatic from symptomatic plaques, whereas GSM values did not. There was a positive correlation between CD68 expression and FDG uptake (r = 0.50, p = 0.04). CONCLUSIONS: Our results...

  16. New dimensions in mechanical plaque control: An overview

    Directory of Open Access Journals (Sweden)

    Arnab Mandal

    2017-01-01

    Full Text Available Plaque control is the daily removal of dental plaque, oral biofilm and also prevention of their accumulation on the teeth and other parts of oral cavity. Dental plaque is the major etiology of maximum gingival and periodontal diseases. It is also related with various dental problems. Mechanical plaque control is a very effective method to get rid of plaque accumulation in oral cavity. In 3000 BC there was the first toothbrush invented by human beings. With time several modifications came in toothbrushes to make mechanical plaque control more effective in day to day oral hygiene practice. This article emphasizes on the advanced and emerging tools in mechanical plaque control methods in attaining an optimal level of oral hygiene standards and maintenance of oral health.

  17. Reliability and discriminatory power of methods for dental plaque quantification

    Directory of Open Access Journals (Sweden)

    Daniela Prócida Raggio

    2010-04-01

    Full Text Available OBJECTIVE: This in situ study evaluated the discriminatory power and reliability of methods of dental plaque quantification and the relationship between visual indices (VI and fluorescence camera (FC to detect plaque. MATERIAL AND METHODS: Six volunteers used palatal appliances with six bovine enamel blocks presenting different stages of plaque accumulation. The presence of plaque with and without disclosing was assessed using VI. Images were obtained with FC and digital camera in both conditions. The area covered by plaque was assessed. Examinations were done by two independent examiners. Data were analyzed by Kruskal-Wallis and Kappa tests to compare different conditions of samples and to assess the inter-examiner reproducibility. RESULTS: Some methods presented adequate reproducibility. The Turesky index and the assessment of area covered by disclosed plaque in the FC images presented the highest discriminatory powers. CONCLUSION: The Turesky index and images with FC with disclosing present good reliability and discriminatory power in quantifying dental plaque.

  18. Intensive lipid-lowering therapy with rosuvastatin stabilizes lipid-rich coronary plaques. Evaluation using dual-source computed tomography

    International Nuclear Information System (INIS)

    Soeda, Tsunenari; Uemura, Shiro; Okayama, Satoshi

    2011-01-01

    Clinical studies using invasive modalities have reported that statin therapy stabilizes coronary plaque vulnerability. The serial changes of lipid-rich coronary plaques (LRCPs) during rosuvastatin treatment were evaluated non-invasively in patients with acute coronary syndrome (ACS) using dual-source computed tomography (DSCT). A total of 11 consecutive ACS patients, and 13 LRCPs were serially evaluated on DSCT before and 24 weeks after rosuvastatin treatment. Compared with the baseline, there was no change in post-treatment minimal lumen diameter, lumen volume, or longitudinal length of LRCPs. By contrast, the ratio of lipid core volume to plaque volume significantly decreased from 48.0±9.9% to 43.7±10.6% (P=0.04), and plaque volume decreased from 144.5±85.5 mm 3 to 119.8±78.0 mm 3 (P=0.07). The remodeling index of target LRCPs significantly decreased from 1.16±0.10 to 1.06±0.12 (P=0.02). Percent reduction of plaque volume was significantly greater in patients with a lower ratio of low-density lipoprotein to high-density lipoprotein (L/H ratio ≤1.5) at follow-up than patients with higher L/H ratio (>1.5; median -31.7% vs. -6.8%, P=0.03). Rosuvastatin therapy reduced the volume of lipid cores and LRCPs and increased the CT attenuation value of LRCPs. DSCT is an effective modality for the non-invasive evaluation of LRCPs in patients with ACS. (author)

  19. Oculocutaneous albinism complicated with an ulcerated plaque

    Directory of Open Access Journals (Sweden)

    Lokanatha Keshavalu

    2013-04-01

    Full Text Available A 32-year-old male with a history of albinism and farmer by occupation presented with an ulcerated plaque on the right wrist. The patient had light eyes, hair, and skin. Physical examination showed extensive photodamage. A skin biopsy specimen from the plaque revealed a well-differentiated squamous-cell carcinoma. Wide surgical excision was done. The most common types of oculocutaneous albinism (OCA, OCA 1 and OCA 2, are autosomal recessive disorders of pigmentation that commonly affect the skin, hair and eyes. Photodamage and skin cancers plague patients with albinism. Albinos face a myriad of social and medical issues. Importance of photoprotection, skin cancer surveillance and treatment has been stressed upon in this report.

  20. Brain Tumor Therapy-Induced Changes in Normal-Appearing Brainstem Measured With Longitudinal Diffusion Tensor Imaging

    International Nuclear Information System (INIS)

    Hua Chiaho; Merchant, Thomas E.; Gajjar, Amar; Broniscer, Alberto; Zhang, Yong; Li Yimei; Glenn, George R.; Kun, Larry E.; Ogg, Robert J.

    2012-01-01

    Purpose: To characterize therapy-induced changes in normal-appearing brainstems of childhood brain tumor patients by serial diffusion tensor imaging (DTI). Methods and Materials: We analyzed 109 DTI studies from 20 brain tumor patients, aged 4 to 23 years, with normal-appearing brainstems included in the treatment fields. Those with medulloblastomas, supratentorial primitive neuroectodermal tumors, and atypical teratoid rhabdoid tumors (n = 10) received postoperative craniospinal irradiation (23.4–39.6 Gy) and a cumulative dose of 55.8 Gy to the primary site, followed by four cycles of high-dose chemotherapy. Patients with high-grade gliomas (n = 10) received erlotinib during and after irradiation (54–59.4 Gy). Parametric maps of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were computed and spatially registered to three-dimensional radiation dose data. Volumes of interest included corticospinal tracts, medial lemnisci, and the pons. Serving as an age-related benchmark for comparison, 37 DTI studies from 20 healthy volunteers, aged 6 to 25 years, were included in the analysis. Results: The median DTI follow-up time was 3.5 years (range, 1.6–5.0 years). The median mean dose to the pons was 56 Gy (range, 7–59 Gy). Three patterns were seen in longitudinal FA and apparent diffusion coefficient changes: (1) a stable or normal developing time trend, (2) initial deviation from normal with subsequent recovery, and (3) progressive deviation without evidence of complete recovery. The maximal decline in FA often occurred 1.5 to 3.5 years after the start of radiation therapy. A full recovery time trend could be observed within 4 years. Patients with incomplete recovery often had a larger decline in FA within the first year. Radiation dose alone did not predict long-term recovery patterns. Conclusions: Variations existed among individual patients after therapy in longitudinal evolution of brainstem white matter injury and recovery. Early response

  1. Regressing Atherosclerosis by Resolving Plaque Inflammation

    Science.gov (United States)

    2017-07-01

    regression requires the alteration of macrophages in the plaques to a tissue repair “alternatively” activated state. This switch in activation state... tissue repair “alternatively” activated state. This switch in activation state requires the action of TH2 cytokines interleukin (IL)-4 or IL-13. To...regulation of tissue macrophage and dendritic cell population dynamics by CSF-1. J Exp Med. 2011;208(9):1901–1916. 35. Xu H, Exner BG, Chilton PM

  2. The auditory brainstem response in two lizard species

    DEFF Research Database (Denmark)

    Brittan-Powell, Elizabeth F; Christensen-Dalsgaard, Jakob; Tang, Yezhong

    2010-01-01

    Although lizards have highly sensitive ears, it is difficult to condition them to sound, making standard psychophysical assays of hearing sensitivity impractical. This paper describes non-invasive measurements of the auditory brainstem response (ABR) in both Tokay geckos (Gekko gecko; nocturnal...... animals, known for their loud vocalizations) and the green anole (Anolis carolinensis, diurnal, non-vocal animals). Hearing sensitivity was measured in 5 geckos and 7 anoles. The lizards were sedated with isoflurane, and ABRs were measured at levels of 1 and 3% isoflurane. The typical ABR waveform......). Above 5 kHz, however, anoles were more than 20 dB more sensitive than geckos and showed a wider range of sensitivity (1-7 kHz). Generally, thresholds from ABR audiograms were comparable to those of small birds. Best hearing sensitivity, however, extended over a larger frequency range in lizards than...

  3. Macrophage antioxidant protection within atherosclerotic plaques.

    Science.gov (United States)

    Gieseg, Steven P; Leake, David S; Flavall, Elizabeth M; Amit, Zunika; Reid, Linzi; Yang, Ya-Ting

    2009-01-01

    Macrophage cells within inflammatory lesions are exposed to a wide range of degrading and cytotoxic molecules including reactive oxygen species. Unlike neutrophils, macrophages do not normally die in this environment but continue to generate oxidants, phagocytose cellular remains, and release a range of cyto-active agents which modulate the immune response. It is this potential of the macrophage cell to survive in an oxidative environment that allows the growth and complexity of advanced atherosclerotic plaques. This review will examine the oxidants encountered by macrophages within an atherosclerotic plaque and describe some of the potential antioxidant mechanisms which enable macrophages to function within inflammatory lesions. Ascorbate, a-tocopherol, and glutathione appear to be central to the protection of macrophages yet additional antioxidant mechanisms appear to be involved. Gamma-Interferon causes macrophages to generate 7,8-dihydroneopterin, neopterin and 3-hydroxyanthranilic acid both of which have antioxidant properties. Manganese superoxide dismutase is also upregulated in macrophages. The evidence that these antioxidants provide further protection, so allowing the macrophage cells to survive within sites of chronic inflammation such as atherosclerotic plaques, will be described.

  4. Mechanisms of erosion of atherosclerotic plaques.

    Science.gov (United States)

    Quillard, Thibaut; Franck, Grégory; Mawson, Thomas; Folco, Eduardo; Libby, Peter

    2017-10-01

    The present review explores the mechanisms of superficial intimal erosion, a common cause of thrombotic complications of atherosclerosis. Human coronary artery atheroma that give rise to thrombosis because of erosion differ diametrically from those associated with fibrous cap rupture. Eroded lesions characteristically contain few inflammatory cells, abundant extracellular matrix, and neutrophil extracellular traps (NETs). Innate immune mechanisms such as engagement of Toll-like receptor 2 (TLR2) on cultured endothelial cells can impair their viability, attachment, and ability to recover a wound. Hyaluronan fragments may serve as endogenous TLR2 ligands. Mouse experiments demonstrate that flow disturbance in arteries with neointimas tailored to resemble features of human eroded plaques disturbs endothelial cell barrier function, impairs endothelial cell viability, recruits neutrophils, and provokes endothelial cells desquamation, NET formation, and thrombosis in a TLR2-dependent manner. Mechanisms of erosion have received much less attention than those that provoke plaque rupture. Intensive statin treatment changes the characteristic of plaques that render them less susceptible to rupture. Thus, erosion may contribute importantly to the current residual burden of risk. Understanding the mechanisms of erosion may inform the development and deployment of novel therapies to combat the remaining atherothrombotic risk in the statin era.

  5. Helicobacter pylori in dental plaque; is it related to brushing frequency, plaque load and oral health status?

    Science.gov (United States)

    Chaudhry, Saima; Khan, Ayyaz Ali; Butt, Arshad Kamal; Idrees, Muhammad; Izhar, Mateen; Iqbal, Hafiz Aamer

    2011-10-01

    To determine the relation between presence of H. pylori in supra-gingival dental plaque with oral hygiene habits and oral health status of patients suffering from symptomatic dyspepsia. Descriptive study. The Department of Oral Health Sciences, Shaikh Zayed FPGMI, Lahore, from September 2008 to August 2009. One hundred and fifty dyspeptic subjects with dental plaque were enrolled. After recording brushing frequency, oral health status and plaque load, the supra-gingival dental plaque samples were collected by sterile curettes. Helicobacter pylori were detected in dental plaque samples through PCR assay. Presence of H. pylori in dental plaque was found to be 37.5% in the sample. Most of the subjects brushed once daily, had plaque index score of 1 and had fair to poor oral hygiene status. Approximately 35% of the individuals who brushed once or twice a day harbored the bacterium in their dental plaque. There was no difference between bacterial detection rates among different categories of plaque index and oral health status of the study subjects. Presence of H. pylori in dental plaque was found to be associated with neither brushing frequency nor with the plaque load nor with the oral health status of individuals suffering from symptomatic dyspepsia.

  6. A Clinical Research Study of Cognitive Dysfunction and Affective Impairment after Isolated Brainstem Stroke

    Directory of Open Access Journals (Sweden)

    Xiujuan Fu

    2017-12-01

    Full Text Available Although the function of the cerebellum in neurocognition has been well-documented, the similar role of the brainstem has yet to be fully elucidated. This clinical research study aimed to combine data relating to neuropsychological assessments and P300 to explore cognitive dysfunction and affective impairment following brainstem stroke. Thirty-four patients with isolated brainstem stroke and twenty-six healthy controls were recruited; for each patient, we collated data pertaining to the P300, Addenbrooke's Cognitive Examination III (ACE-III, Montreal Cognitive Assessment Chinese version (MoCA, trail-making test (TMT, Symbol Digit Modalities Test (SDMT, Wechsler Adult Intelligence Scale-Digit Spans (DS, Stroop test, Self Rating Depression Scale (SDS, and Self Rating Anxiety Scale (SAS. Significance was analyzed using an independent T-test or the Mann-Whitney U-test. Correlation was analyzed using Pearson's correlation analysis or Spearman's correlation analysis. Collectively, data revealed that brainstem stroke caused mild cognitive impairment (MCI, and that visuospatial, attention, linguistic, and emotional disturbances may occur after isolated brainstem stroke. Cognitive decline was linked to P300 latency, ACE-III, and MoCA; P300 latency was correlated with ACE-III. Patients with right brainstem lesions were more likely to suffer memory decline. The present study provides initial data relating to the role of the brainstem in neurocognition, and will be useful for further understanding of vascular cognitive and affective impairment.

  7. A Clinical Research Study of Cognitive Dysfunction and Affective Impairment after Isolated Brainstem Stroke

    Science.gov (United States)

    Fu, Xiujuan; Lu, Zuneng; Wang, Yan; Huang, Lifang; Wang, Xi; Zhang, Hong; Xiao, Zheman

    2017-01-01

    Although the function of the cerebellum in neurocognition has been well-documented, the similar role of the brainstem has yet to be fully elucidated. This clinical research study aimed to combine data relating to neuropsychological assessments and P300 to explore cognitive dysfunction and affective impairment following brainstem stroke. Thirty-four patients with isolated brainstem stroke and twenty-six healthy controls were recruited; for each patient, we collated data pertaining to the P300, Addenbrooke's Cognitive Examination III (ACE-III), Montreal Cognitive Assessment Chinese version (MoCA), trail-making test (TMT), Symbol Digit Modalities Test (SDMT), Wechsler Adult Intelligence Scale-Digit Spans (DS), Stroop test, Self Rating Depression Scale (SDS), and Self Rating Anxiety Scale (SAS). Significance was analyzed using an independent T-test or the Mann-Whitney U-test. Correlation was analyzed using Pearson's correlation analysis or Spearman's correlation analysis. Collectively, data revealed that brainstem stroke caused mild cognitive impairment (MCI), and that visuospatial, attention, linguistic, and emotional disturbances may occur after isolated brainstem stroke. Cognitive decline was linked to P300 latency, ACE-III, and MoCA; P300 latency was correlated with ACE-III. Patients with right brainstem lesions were more likely to suffer memory decline. The present study provides initial data relating to the role of the brainstem in neurocognition, and will be useful for further understanding of vascular cognitive and affective impairment. PMID:29311895

  8. Relationship Between Quantitative Adverse Plaque Features From Coronary Computed Tomography Angiography and Downstream Impaired Myocardial Flow Reserve by 13N-Ammonia Positron Emission Tomography: A Pilot Study.

    Science.gov (United States)

    Dey, Damini; Diaz Zamudio, Mariana; Schuhbaeck, Annika; Juarez Orozco, Luis Eduardo; Otaki, Yuka; Gransar, Heidi; Li, Debiao; Germano, Guido; Achenbach, Stephan; Berman, Daniel S; Meave, Aloha; Alexanderson, Erick; Slomka, Piotr J

    2015-10-01

    We investigated the relationship of quantitative plaque features from coronary computed tomography (CT) angiography and coronary vascular dysfunction by impaired myocardial flow reserve (MFR) by (13)N-Ammonia positron emission tomography (PET). Fifty-one patients (32 men, 62.4±9.5 years) underwent combined rest-stress (13)N-ammonia PET and CT angiography scans by hybrid PET/CT. Regional MFR was measured from PET. From CT angiography, 153 arteries were evaluated by semiautomated software, computing arterial noncalcified plaque (NCP), low-density NCP (NCP<30 HU), calcified and total plaque volumes, and corresponding plaque burden (plaque volumex100%/vessel volume), stenosis, remodeling index, contrast density difference (maximum difference in luminal attenuation per unit area in the lesion), and plaque length. Quantitative stenosis, plaque burden, and myocardial mass were combined by boosted ensemble machine-learning algorithm into a composite risk score to predict impaired MFR (MFR≤2.0) by PET in each artery. Nineteen patients had impaired regional MFR in at least 1 territory (41/153 vessels). Patients with impaired regional MFR had higher arterial NCP (32.4% versus 17.2%), low-density NCP (7% versus 4%), and total plaque burden (37% versus 19.3%, P<0.02). In multivariable analysis with 10-fold cross-validation, NCP burden was the most significant predictor of impaired MFR (odds ratio, 1.35; P=0.021 for all). For prediction of impaired MFR with 10-fold cross-validation, receiver operating characteristics area under the curve for the composite score was 0.83 (95% confidence interval, 0.79-0.91) greater than for quantitative stenosis (0.66, 95% confidence interval, 0.57-0.76, P=0.005). Compared with stenosis, arterial NCP burden and a composite score combining quantitative stenosis and plaque burden from CT angiography significantly improves identification of downstream regional vascular dysfunction. © 2015 American Heart Association, Inc.

  9. Kinetics of hemolytic plaque formation. IV. IgM plaque inhibition

    Energy Technology Data Exchange (ETDEWEB)

    DeLisi, C

    1975-01-01

    An analysis of the inhibition of hemolytic plaques formed against IgM antibodies is presented. The starting point is the equations of DeLisi and Bell (1974) which describe the kinetics of plaque growth, and DeLisi and Goldstein (1975) which describe inhibition of IgG plaques. However, the physical chemical models which were used previously to describe IgG inhibition data are shown to be inadequate for describing the characteristics of IgM inhibition curves. Moreover, it is shown that the experimental results place severe restrictions on the possible choices of physical chemical models for IgM upon which to base the calculations. It is argued that in order to account even qualitatively for all the data, one must assume (1) a very restricted motion of IgMs about the Fab hinge region and (2) a very narrow secretion rate distribution of IgM by antibody secreting cells. (auth)

  10. Effects of myelin or cell body brainstem lesions on 3-channel Lissajous' trajectories of feline auditory brainstem evoked potentials.

    Science.gov (United States)

    Pratt, H; Zaaroor, M; Bleich, N; Starr, A

    1991-06-01

    Auditory brainstem evoked potentials (ABEP) were recorded from 16 awake cats to obtain 3-Channel Lissajous' Trajectories (3CLTs) using three orthogonal differential electrode configurations (nasion-midline nuchal ridge, left-right mastoids, vertex-midline under the mandible). Potentials, evoked by monaural 80 dBnHL (re, human threshold) clicks, were studied before, and up to 7 weeks after inducing neuronal lesions localized to the cochlear nucleus (CN) or the superior olivary complex (SOC), or myelin lesions localized to the fibers of the trapezoid body connecting these two structures. Neuronal lesions were induced by injection of kainic acid (KA), while myelin lesions were induced by injection of L-alpha-lysophosphatidylcholine (LPC). With CN neuronal lesions the major changes in 3CLT were in the time domain of 'b', 'c' and 'd' (components P2, P3 and P4 of single-channel ABEP). With SOC neuronal lesions the major changes were in 'c' and 'd' of 3CLT (P3 and P4 of ABEP). With trapezoid body lesions the major change was in 'c' (P3 of ABEP). The results are compatible with the peripheral generation of the first ABEP components (P1a and P1b). The second component (P2) is generated by ipsilateral CN neurones and their outputs. The third component (P3) is generated primarily by ipsilateral SOC neurones and their outputs, with the ipsilateral CN providing input. The The fourth component (P4) is generated bilaterally by the SOC neurones and their outputs, receiving their inputs from ipsilateral CN. The fifth ABEP component (P5) is generated by structures central to the SOCs and their immediate outputs. Neither focal neuronal nor myelin lesions were sufficient to produce obliteration of any component, consistent with a set of generators for each of the ABEP components, consisting of both cell bodies and their output fibers, that is distributed spatially in the brainstem.

  11. Micro-analysis of plaque fluid from single-site fasted plaque

    International Nuclear Information System (INIS)

    Vogel, G.L.; Carey, C.M.; Chow, L.C.; Tatevossian, A.

    1990-01-01

    Despite the site-specific nature of caries, nearly all data on the concentration of ions relevant to the level of saturation of plaque fluid with respect to calcium phosphate minerals or enamel are from studies that used pooled samples. A procedure is described for the collection and analysis of inorganic ions relevant to these saturation levels in plaque fluid samples collected from a single surface on a single tooth. Various methods for examining data obtained by this procedure are described, and a mathematical procedure employing potential plots is recommended

  12. The utility of preoperative diffusion tensor imaging in the surgical management of brainstem cavernous malformations.

    Science.gov (United States)

    Flores, Bruno C; Whittemore, Anthony R; Samson, Duke S; Barnett, Samuel L

    2015-03-01

    Resection of brainstem cavernous malformations (BSCMs) may reduce the risk of stepwise neurological deterioration secondary to hemorrhage, but the morbidity of surgery remains high. Diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) are neuroimaging techniques that may assist in the complex surgical planning necessary for these lesions. The authors evaluate the utility of preoperative DTI and DTT in the surgical management of BSCMs and their correlation with functional outcome. A retrospective review was conducted to identify patients who underwent resection of a BSCM between 2007 and 2012. All patients had preoperative DTI/DTT studies and a minimum of 6 months of clinical and radiographic follow-up. Five major fiber tracts were evaluated preoperatively using the DTI/DTT protocol: 1) corticospinal tract, 2) medial lemniscus and medial longitudinal fasciculus, 3) inferior cerebellar peduncle, 4) middle cerebellar peduncle, and 5) superior cerebellar peduncle. Scores were applied according to the degree of distortion seen, and the sum of scores was used for analysis. Functional outcomes were measured at hospital admission, discharge, and last clinic visit using modified Rankin Scale (mRS) scores. Eleven patients who underwent resection of a BSCM and preoperative DTI were identified. The mean age at presentation was 49 years, with a male-to-female ratio of 1.75:1. Cranial nerve deficit was the most common presenting symptom (81.8%), followed by cerebellar signs or gait/balance difficulties (54.5%) and hemibody anesthesia (27.2%). The majority of the lesions were located within the pons (54.5%). The mean diameter and estimated volume of lesions were 1.21 cm and 1.93 cm(3), respectively. Using DTI and DTT, 9 patients (82%) were found to have involvement of 2 or more major fiber tracts; the corticospinal tract and medial lemniscus/medial longitudinal fasciculus were the most commonly affected. In 2 patients with BSCMs without pial presentation, DTI

  13. Temperature distribution in atherosclerotic coronary arteries: influence of plaque geometry and flow (a numerical study)

    International Nuclear Information System (INIS)

    Have, A G ten; Gijsen, F J H; Wentzel, J J; Slager, C J; Steen, A F W van der

    2004-01-01

    Intravascular coronary thermography is a method that may detect vulnerable, atherosclerotic plaques and is currently evaluated in a clinical setting. Active macrophages or enzymatic heat releasing processes in vulnerable plaques may act as heat sources. To better understand the parameters of influence on thermographic measurements, numerical simulations have been performed on a model of a coronary artery segment containing a heat source. Heat source parameters and flow were varied to study their influence on temperatures at the lumen wall. Maximal temperature differences at the lumen wall increased when the source volume increased and they differ with the source geometry. The simulations showed that blood flow acts as a coolant to the lumen wall. Blood flow decreased maximal temperatures depending on the source geometry, source volume and the maximal flow velocity. Influence of flow was highest for circumferentially extended sources, up to a factor 3.7, and lowest for longitudinally extended sources, down to a factor 1.9. When cap thickness increased, maximal temperatures decreased and the influence of flow increased. This study shows that correct interpretation of intravascular thermographic measurements requires data on the flow and on the morphologic characteristics of the atherosclerotic plaque

  14. Cell surface hydrophobicity of dental plaque microorganisms in situ.

    OpenAIRE

    Rosenberg, M; Judes, H; Weiss, E

    1983-01-01

    The cell surface hydrophobicity of bacteria obtained directly from human tooth surfaces was assayed by measuring their adherence to liquid hydrocarbons. Fresh samples of supragingival dental plaque were washed and dispersed in buffer. Adherence of the plaque microorganisms to hexadecane, octane, and xylene was tested turbidimetrically and by direct microscopic observation. The results clearly show that the vast majority of bacteria comprising dental plaque exhibit pronounced cell surface hydr...

  15. Dosimetric Benefit of a New Ophthalmic Radiation Plaque

    Energy Technology Data Exchange (ETDEWEB)

    Marwaha, Gaurav, E-mail: marwahg2@ccf.org [Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic Foundation, Cleveland, Ohio (United States); Cleveland Clinic Foundation, Cleveland, Ohio (United States); Wilkinson, Allan [Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic Foundation, Cleveland, Ohio (United States); Cleveland Clinic Foundation, Cleveland, Ohio (United States); Bena, James [Department of Quantitative Health Sciences, Cleveland Clinic Foundation, Cleveland, Ohio (United States); Cleveland Clinic Foundation, Cleveland, Ohio (United States); Macklis, Roger [Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic Foundation, Cleveland, Ohio (United States); Cleveland Clinic Foundation, Cleveland, Ohio (United States); Singh, Arun D. [Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic Foundation, Cleveland, Ohio (United States); Department of Ophthalmic Oncology, Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, Ohio (United States); Cleveland Clinic Foundation, Cleveland, Ohio (United States)

    2012-12-01

    Purpose: To determine whether the computed dosimetry of a new ophthalmic plaque, EP917, when compared with the standard Collaborative Ocular Melanoma Study (COMS) plaques, could reduce radiation exposure to vision critical structures of the eye. Methods and Materials: One hundred consecutive patients with uveal melanoma treated with COMS radiation plaques between 2007 and 2010 were included in this study. These treatment plans were generated with the use of Bebig Plaque Simulator treatment-planning software, both for COMS plaques and for EP917 plaques using I-125. Dose distributions were calculated for a prescription of 85 Gy to the tumor apex. Doses to the optic disc, opposite retina, lens, and macula were obtained, and differences between the 2 groups were analyzed by standard parametric methods. Results: When compared with the COMS plaques, the EP917 plaques used fewer radiation seeds by an average difference of 1.94 (P<.001; 95% confidence interval [CI], -2.8 to -1.06) and required less total strength of radiation sources by an average of 17.74 U (air kerma units) (P<.001; 95% CI, -20.16 to -15.32). The total radiation doses delivered to the optic disc, opposite retina, and macula were significantly less by 4.57 Gy, 0.50 Gy, and 11.18 Gy, respectively, with the EP917 plaques vs the COMS plaques. Conclusion: EP917 plaques deliver less overall radiation exposure to critical vision structures than COMS treatment plaques while still delivering the same total therapeutic dose to the tumor.

  16. Dosimetric Benefit of a New Ophthalmic Radiation Plaque

    International Nuclear Information System (INIS)

    Marwaha, Gaurav; Wilkinson, Allan; Bena, James; Macklis, Roger; Singh, Arun D.

    2012-01-01

    Purpose: To determine whether the computed dosimetry of a new ophthalmic plaque, EP917, when compared with the standard Collaborative Ocular Melanoma Study (COMS) plaques, could reduce radiation exposure to vision critical structures of the eye. Methods and Materials: One hundred consecutive patients with uveal melanoma treated with COMS radiation plaques between 2007 and 2010 were included in this study. These treatment plans were generated with the use of Bebig Plaque Simulator treatment-planning software, both for COMS plaques and for EP917 plaques using I-125. Dose distributions were calculated for a prescription of 85 Gy to the tumor apex. Doses to the optic disc, opposite retina, lens, and macula were obtained, and differences between the 2 groups were analyzed by standard parametric methods. Results: When compared with the COMS plaques, the EP917 plaques used fewer radiation seeds by an average difference of 1.94 (P<.001; 95% confidence interval [CI], −2.8 to −1.06) and required less total strength of radiation sources by an average of 17.74 U (air kerma units) (P<.001; 95% CI, −20.16 to −15.32). The total radiation doses delivered to the optic disc, opposite retina, and macula were significantly less by 4.57 Gy, 0.50 Gy, and 11.18 Gy, respectively, with the EP917 plaques vs the COMS plaques. Conclusion: EP917 plaques deliver less overall radiation exposure to critical vision structures than COMS treatment plaques while still delivering the same total therapeutic dose to the tumor.

  17. Prophylaxis for infective endocarditis: antibiotic sensitivity of dental plaque.

    OpenAIRE

    MacFarlane, T W; McGowan, D A; Hunter, K; MacKenzie, D

    1983-01-01

    The antibiotic sensitivity pattern of bacteria isolated from bacteraemia after dental extraction was compared with that of bacteria isolated from dental plaque samples from the same patient. The results supported the current practice of using penicillin and erythromycin empirically for prophylaxis. The prediction of the most appropriate antibiotic for prophylaxis using dental plaque samples was most accurate when the minimum inhibitory concentration (MIC) of plaque isolates were used. It appe...

  18. Relationship between left main coronary artery plaque burden and nonleft main coronary atherosclerosis: results from the PROSPECT study.

    Science.gov (United States)

    Shimizu, Takehisa; Mintz, Gary S; De Bruyne, Bernard; Farhat, Naim Z; Inaba, Shinji; Cao, Yang; Marso, Steven P; Weisz, Giora; Serruys, Patrick W; Stone, Gregg W; Maehara, Akiko

    2018-05-17

    Whether the severity of left main coronary artery (LMCA) disease reflects LMCA and overall coronary atherosclerotic burden is not known. We aimed to assess nonculprit LMCA disease characteristics and the relationship with atherosclerosis in the rest of the coronary arteries as well as patient outcomes. In the PROSPECT study, 697 patients with acute coronary syndromes underwent three-vessel gray-scale and radiofrequency intravascular ultrasound after percutaneous coronary intervention. Overall, 552 patients with adequate LMCA imaging were compared according to LMCA plaque burden. The tertile with the highest plaque burden in the LMCA had the smallest LMCA minimum lumen area (17.4, 14.2, 10.5, lowest through highest tertiles, respectively, PPROSPECT predictors of future nonculprit major adverse cardiac events (MACE) (minimum lumen area≤4 mm, plaque burden≥70%, and virtual histology thin-cap fibroatheroma), the tertile with the highest LMCA plaque burden had the highest number of patients with at least one of three PROSPECT predictors (P=0.03). In multivariable model, though total atheroma volume (per 1%) was an independent predictor of all MACE [hazard ratio (95% confidence interval)=1.06 (1.01-1.11), P=0.02] and strong trend for non-culprit-related MACE [hazard ratio (95% confidence interval)=1.06 (1.00-1.13), P=0.06], plaque burden at LMCA was not (all MACE, P=0.90, non-culprit-related MACE, P=0.85). The severity of atherosclerosis in LMCA predicted the overall atherosclerotic plaque burden as well as the presence of high-risk plaques in the three major epicardial coronary arteries.

  19. Effect of longitudinal anatomical mismatch of stenting on the mechanical environment in human carotid artery with atherosclerotic plaques.

    Science.gov (United States)

    Fan, Zhenmin; Liu, Xiao; Sun, Anqiang; Zhang, Nan; Fan, Zhanming; Fan, Yubo; Deng, Xiaoyan

    2017-10-01

    Longitudinal anatomic mismatch (LAM) of stenting (i.e., a stenotic artery segment is not fully covered by a deployed stent) worsens the mechanical environment in the treated artery, which most likely is the cause for the associated high risks of restenosis, myocardial infarction and stent thrombosis. To probe the possibility, we constructed a patient-specific carotid model with two components of plaques (lipid and calcified plaque) based on MRI images; we numerically compared three different stenting scenarios in terms of von Mises stress (VMS) distribution in the treated arteries, namely, the short stenting (LAM), the medium stenting and the long stenting. The results showed that the short stenting led to more areas with abnormally high VMS along the inner surface of the treated artery with a much higher surface-averaged VMS at the distal end of the stent than both the medium and long stenting. While the VMS distribution in the calcified plaques was similar for the three stenting models, it was quite different in the lipid plaques among the three stenting models. The lipid plaque of the short-stent model showed more volume of the lipid plaque subjected to high VMS than those of the other two models. Based on the obtained results, we may infer that the short stenting (i.e., LAM) may aggravate vascular injury due to high VMS on the artery-stent interaction surface and within the lipid plaque. Therefore, to obtain a better outcome, a longer stent, rather than a short one, might be needed for arterial stenting. Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.

  20. Quantification of plaque lipids in the aortic root of ApoE-deficient mice by 3D DIXON magnetic resonance imaging in an ex vivo model

    International Nuclear Information System (INIS)

    Dietel, Barbara; Kuehn, Constanze; Achenbach, Stephan; Budinsky, Lubos; Uder, Michael; Hess, Andreas

    2015-01-01

    To establish a dedicated protocol for the three-dimensional (3D) quantification of plaque lipids in apolipoprotein E-deficient (apoE -/- ) mice using ex vivo MRI. ApoE -/- mice were fed a high-fat diet (n = 10) or normal food (n = 10) for 3 months. Subsequently, a 3D FLASH MRI sequence was used to view the anatomy of the aortic root in the isolated hearts, where a 3D double-echo two-excitation pulse sequence (DIXON sequence) was used to selectively image plaque lipids. The vessel wall, lumen and plaque lipid volumes were quantified by MRI and histology for correlation analysis. DIXON MRI allowed visualisation and accurate quantification of plaque lipids. When comparing the vessel wall, lumen and plaque lipid sizes in the aortic root, Bland-Altman and linear regression analysis revealed a close correlation between MRI results and the histological data both on a slice-by-slice basis and of the volumetric measurements (vessel wall: r 2 = 0.775, p 2 = 0.875; p = 0.002; plaque lipid: r 2 = 0.819, p = 0.003). The combination of 3D FLASH and DIXON-sequence MRI permits an accurate ex vivo assessment of the investigated plaque parameters in the aortic root of mice, particularly the lipid content. (orig.)

  1. Binaural interaction in the auditory brainstem response: a normative study.

    Science.gov (United States)

    Van Yper, Lindsey N; Vermeire, Katrien; De Vel, Eddy F J; Battmer, Rolf-Dieter; Dhooge, Ingeborg J M

    2015-04-01

    Binaural interaction can be investigated using auditory evoked potentials. A binaural interaction component can be derived from the auditory brainstem response (ABR-BIC) and is considered evidence for binaural interaction at the level of the brainstem. Although click ABR-BIC has been investigated thoroughly, data on 500 Hz tone-burst (TB) ABR-BICs are scarce. In this study, characteristics of click and 500 Hz TB ABR-BICs are described. Furthermore, reliability of both click and 500 Hz TB ABR-BIC are investigated. Eighteen normal hearing young adults (eight women, ten men) were included. ABRs were recorded in response to clicks and 500 Hz TBs. ABR-BICs were derived by subtracting the binaural response from the sum of the monaural responses measured in opposite ears. Good inter-rater reliability is obtained for both click and 500 Hz TB ABR-BICs. The most reliable peak in click ABR-BIC occurs at a mean latency of 6.06 ms (SD 0.354 ms). Reliable 500 Hz TB ABR-BIC are obtained with a mean latency of 9.47 ms (SD 0.678 ms). Amplitudes are larger for 500 Hz TB ABR-BIC than for clicks. The most reliable peak in click ABR-BIC occurs at the downslope of wave V. Five hundred Hertz TB ABR-BIC is characterized by a broad positivity occurring at the level of wave V. The ABR-BIC is a useful technique to investigate binaural interaction in certain populations. Examples are bilateral hearing aid users, bilateral cochlear implant users and bimodal listeners. The latter refers to the combination of unilateral cochlear implantation and contralateral residual hearing. The majority of these patients have residual hearing in the low frequencies. The current study suggests that 500 Hz TB ABR-BIC may be a suitable technique to assess binaural interaction in this specific population of cochlear implant users. Copyright © 2014 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  2. Atherosclerotic Plaque Characteristics by CT Angiography Identify Coronary Lesions That Cause Ischemia: a Direct Comparison to Fractional Flow Reserve

    Science.gov (United States)

    Park, Hyung-Bok; Heo, Ran; Hartaigh, Bríain ó; Cho, Iksung; Gransar, Heidi; Nakazato, Ryo; Leipsic, Jonathon; Mancini, G.B. John; Koo, Bon-Kwon; Otake, Hiromasa; Budoff, Matthew J.; Berman, Daniel S.; Erglis, Andrejs; Chang, Hyuk-Jae; Min, James K.

    2014-01-01

    Objective We evaluated the association between atherosclerotic plaque characteristics (APCs) by coronary CT angiography (CT) and lesion ischemia by fractional flow reserve (FFR). Background FFR is the gold standard for determining lesion ischemia. While APCs by CT—including aggregate plaque volume % (%APV), positive remodeling (PR), low attenuation plaque (LAP) and spotty calcification (SC)—are associated with future coronary syndromes, their relationship to lesion ischemia is unclear. Methods 252 patients (17 centers, 5 countries) [mean age 63 years, 71% males] underwent CT, with FFR performed for 407 coronary lesions. CT was interpreted for 50% stenosis, with the latter considered obstructive. APCs by CT were defined as: (1) PR, lesion diameter/reference diameter >1.10; (2) LAP, any voxel 50% but not for 50%. PMID:25592691

  3. Congenital milia En plaque on scalp

    Directory of Open Access Journals (Sweden)

    Sangita Ghosh

    2015-01-01

    Full Text Available Milia en plaque is a rare disease entity characterized by confluence of multiple keratin-filled cysts resulting from the obstruction of hair follicle without any preceding primary dermatosis. Fewer than 40 cases have been reported so far in dermatological literature, and most cases are described to occur in adults and in the peri-auricular area. We describe a case of congenital MEP on scalp of a five-year-old boy with a blaschkoid extension into posterior nuchal area. This case report claims its uniqueness because of the unusual site and congenital presentation.

  4. The high-risk plaque initiative

    DEFF Research Database (Denmark)

    Falk, Erling; Sillesen, Henrik; Muntendam, Pieter

    2011-01-01

    The High-Risk Plaque (HRP) Initiative is a research and development effort to advance the understanding, recognition, and management of asymptomatic individuals at risk for a near-term atherothrombotic event such as myocardial infarction or stroke. Clinical studies using the newest technologies...... have been initiated, including the BioImage Study in which novel approaches are tested in a typical health plan population. Asymptomatic at-risk individuals were enrolled, including a survey-only group (n = 865), a group undergoing traditional risk factor scoring (n = 718), and a group in which all...

  5. Association of Streptococcus with Plaque Type of Psoriasis

    Directory of Open Access Journals (Sweden)

    Mohammad Akram Hossain

    2015-05-01

    Full Text Available Background: Guttate psoriasis has a well-known association with streptococcal throat infections, but the effects of these infections in patients with chronic plaque type of psoriasis remains to be evaluated. In Bangladesh several studies were done on psoriasis but no data about association between streptococcal throat infection and plaque type psoriasis are available so far. Considering the co-morbidities of psoriasis patients, it might be justifiable to find out the events that provoke the initiation or exacerbation of psoriatic disease process. Objective: To observe the association of streptococcus with plaque type of psoriasis. Materials and Methods: This observational study was conducted in the department of Dermatology and Venereology, Bangabandhu Sheikh Mujib Medical University, Dhaka. Forty seven patients clinically and histopathologically diagnosed as having plaque psoriasis were selected as cases and patients with skin diseases other than psoriasis were selected as controls. Results: In this study majority of subjects (55% were diagnosed as chronic plaque psoriasis. Among the subjects with guttate flare of chronic plaque psoriasis 64.2% gave a positive history of sore throat. ASO titer was raised (>200 IU/mL in 28 (59.5% patients of chronic plaque psoriasis and 7 (17.9% patients of non-psoriatic respondents. The difference between two groups was significant (p0.05. Conclusion: This study shows that streptococcal throat infections are associated with plaque psoriasis and early treatment of throat infections may be beneficial for plaque type of psoriasis patients.

  6. Herpetic brainstem encephalitis: report of a post-mortem case studied electron microscopically and immunohisiochemically

    Directory of Open Access Journals (Sweden)

    José Eymard Homem Pitella

    1987-03-01

    Full Text Available A post-mortem examined case of herpetic brainstem encephalitis is presented. Clinically, the patient had cephalea followed by ataxia, drowsiness and multiple palsies of some cranial nerves, developing into death in eight days. The pathologic examination of the brain showed necrotizing encephalitis in multiple foci limited to the brainstem, more distinctly in the pons and medula oblongata. The technique of immunoperoxidase revealed rare glial cells with intranuclear immunoreactivity for herpes antigen. Rare viral particles with the morphological characteristics of the herpesvirus were identified in the nuclei of neurons in 10% formol fixed material. This is the second reported case of herpetic brainstem encephalitis confirmed by post-mortem examination. The pathway used by the virus to reach the central nervous system and its posterior dissemination to the oral cavity, the orbitofrontal region and the temporal lobes as well as to the brainstem, after a period of latency and reactivation, are discussed.

  7. Leucoencephalopathy with brainstem and spinal cord involvement and high lactate: quantitative magnetic resonance imaging

    NARCIS (Netherlands)

    Steenweg, M.E.; Pouwels, P.J.W.; Wolf, N.I.; van Wieringen, W.N.; Barkhof, F.; van der Knaap, M.S.

    2011-01-01

    Leucoencephalopathy with brainstem and spinal cord involvement and elevated lactate is a white matter disorder caused by DARS2 mutations. The pathology is unknown. We observed striking discrepancies between improvement on longitudinal conventional magnetic resonance images and clinical deterioration

  8. Organization of diencephalic and brainstem afferent projections to the lateral septum in the rat

    NARCIS (Netherlands)

    Luiten, Paul G.M.; Kuipers, Folkert; Schuitmaker, Hans

    1982-01-01

    Ascending diencephalic and brainstem afferents to the lateral septal column were studied by retrograde transport of horseradish peroxidase following microiontophoretic injections in the various subdivisions of the lateral septal area. Predominantly ispilateral cells, of which several coincide with

  9. A probabilistic atlas of human brainstem pathways based on connectome imaging data.

    Science.gov (United States)

    Tang, Yuchun; Sun, Wei; Toga, Arthur W; Ringman, John M; Shi, Yonggang

    2018-04-01

    The brainstem is a critical structure that regulates vital autonomic functions, houses the cranial nerves and their nuclei, relays motor and sensory information between the brain and spinal cord, and modulates cognition, mood, and emotions. As a primary relay center, the fiber pathways of the brainstem include efferent and afferent connections among the cerebral cortex, spinal cord, and cerebellum. While diffusion MRI has been successfully applied to map various brain pathways, its application for the in vivo imaging of the brainstem pathways has been limited due to inadequate resolution and large susceptibility-induced distortion artifacts. With the release of high-resolution data from the Human Connectome Project (HCP), there is increasing interest in mapping human brainstem pathways. Previous works relying on HCP data to study brainstem pathways, however, did not consider the prevalence (>80%) of large distortions in the brainstem even after the application of correction procedures from the HCP-Pipeline. They were also limited in the lack of adequate consideration of subject variability in either fiber pathways or region of interests (ROIs) used for bundle reconstruction. To overcome these limitations, we develop in this work a probabilistic atlas of 23 major brainstem bundles using high-quality HCP data passing rigorous quality control. For the large-scale data from the 500-Subject release of HCP, we conducted extensive quality controls to exclude subjects with severe distortions in the brainstem area. After that, we developed a systematic protocol to manually delineate 1300 ROIs on 20 HCP subjects (10 males; 10 females) for the reconstruction of fiber bundles using tractography techniques. Finally, we leveraged our novel connectome modeling techniques including high order fiber orientation distribution (FOD) reconstruction from multi-shell diffusion imaging and topography-preserving tract filtering algorithms to successfully reconstruct the 23 fiber bundles

  10. Radiobiology for eye plaque brachytherapy and evaluation of implant duration and radionuclide choice using an objective function

    International Nuclear Information System (INIS)

    Gagne, Nolan L.; Leonard, Kara L.; Rivard, Mark J.

    2012-01-01

    Purpose: Clinical optimization of Collaborative Ocular Melanoma Study (COMS) eye plaque brachytherapy is currently limited to tumor coverage, consensus prescription dosage, and dose calculations to ocular structures. The biologically effective dose (BED) of temporary brachytherapy treatments is a function of both chosen radionuclide R and implant duration T. This study endeavored to evaluate BED delivered to the tumor volume and surrounding ocular structures as a function of plaque position P, prescription dose, R, and T. Methods: Plaque-heterogeneity-corrected dose distributions were generated with MCNP5 for the range of currently available COMS plaques loaded with sources using three available low-energy radionuclides. These physical dose distributions were imported into the PINNACLE 3 treatment planning system using the TG-43 hybrid technique and used to generate dose volume histograms for a T = 7 day implant within a reference eye geometry including the ciliary body, cornea, eyelid, foveola, lacrimal gland, lens, optic disc, optic nerve, retina, and tumor at eight standard treatment positions. The equation of Dale and Jones was employed to create biologically effective dose volume histograms (BEDVHs), allowing for BED volumetric analysis of all ROIs. Isobiologically effective prescription doses were calculated for T = 5 days down to 0.01 days, with BEDVHs subsequently generated for all ROIs using correspondingly reduced prescription doses. Objective functions were created to evaluate the BEDVHs as a function of R and T. These objective functions are mathematically accessible and sufficiently general to be applied to temporary or permanent brachytherapy implants for a variety of disease sites. Results: Reducing T from 7 to 0.01 days for a 10 mm plaque produced an average BED benefit of 26%, 20%, and 17% for 103 Pd, 125 I, and 131 Cs, respectively, for all P; 16 and 22 mm plaque results were more position-dependent. 103 Pd produced a 16%–35% BED benefit over

  11. Framework for detection and localization of coronary non-calcified plaques in cardiac CTA using mean radial profiles.

    Science.gov (United States)

    Jawaid, Muhammad Moazzam; Riaz, Atif; Rajani, Ronak; Reyes-Aldasoro, Constantino Carlos; Slabaugh, Greg

    2017-10-01

    The high mortality rate associated with coronary heart disease (CHD) has driven intensive research in cardiac imaging and image analysis. The advent of computed tomography angiography (CTA) has turned non-invasive diagnosis of cardiovascular anomalies into reality as calcified coronary plaques can be easily identified due to their high intensity values. However, the detection of non-calcified plaques in CTA is still a challenging problem because of lower intensity values, which are often similar to the nearby blood and muscle tissues. In this work, we propose the use of mean radial profiles for the detection of non-calcified plaques in CTA imagery. Accordingly, we computed radial profiles by averaging the image intensity in concentric rings around the vessel centreline in a first stage. In the subsequent stage, an SVM classifier is applied to identify the abnormal coronary segments. For occluded segments, we further propose a derivative-based method to localize the position and length of the plaque inside the segment. A total of 32 CTA volumes were analysed and a detection accuracy of 88.4% with respect to the manual expert was achieved. The plaque localization accuracy was computed using the Dice similarity coefficient and a mean of 83.2% was achieved. The consistent performance for multi-vendor, multi-institution data demonstrates the reproducibility of our method across different CTA datasets with a good agreement with manual expert annotations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Combined CMV- and HSV-1 brainstem encephalitis restricted to medulla oblongata.

    Science.gov (United States)

    Katchanov, J; Branding, G; Stocker, H

    2014-04-15

    We report a very rare case of a combined CMV- and HSV-1 isolated brainstem encephalitis restricted to medulla oblongata in a patient with advanced HIV disease. Neither limbic nor general ventricular involvement was detected on neuroimaging. The case highlights the importance of testing for HSV-1 and CMV in HIV-infected patients presenting with an isolated brainstem syndrome. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Newborn hearing screening with transient evoked otoacoustic emissions and automatic auditory brainstem response

    OpenAIRE

    Renata Mota Mamede de Carvallo; Carla Gentile Matas; Isabela de Souza Jardim

    2008-01-01

    Objective: The aim of the present investigation was to check Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response tests applied together in regular nurseries and Newborn Intensive Care Units (NICU), as well as to describe and compare the results obtained in both groups. Methods: We tested 150 newborns from regular nurseries and 70 from NICU. Rresults: The newborn hearing screening results using Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem...

  14. Prodominant hypertensive brainstem encephalopathy with supratentorial involvement: Case report and literature review

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Ji Hee; Park, Sung Tae; Lim, Hyun Kyung [Dept. of Radiology, Soonchunhyang University Hospital, Soonchunhyang University School of Medicine, Seoul (Korea, Republic of); Kim, Sung Tae; Cha, Ji Hoon [Dept. of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2014-12-15

    Hypertensive encephalopathy typically presents with bilateral parietooccipital vasogenic edema. Brainstem and cerebellar edema are uncommon in association with typical supratentorial changes. We experienced three cases of atypical hypertensive encephalopathy involving brainstem and cerebellum as well as cerebral white matter, which showed characteristic alternating linear bright and low signals in the pons, the so-called 'stripe sign'. We report these cases here with a brief literature review.

  15. Auditory Brainstem Responses and EMFs Generated by Mobile Phones.

    Science.gov (United States)

    Khullar, Shilpa; Sood, Archana; Sood, Sanjay

    2013-12-01

    There has been a manifold increase in the number of mobile phone users throughout the world with the current number of users exceeding 2 billion. However this advancement in technology like many others is accompanied by a progressive increase in the frequency and intensity of electromagnetic waves without consideration of the health consequences. The aim of our study was to advance our understanding of the potential adverse effects of GSM mobile phones on auditory brainstem responses (ABRs). 60 subjects were selected for the study and divided into three groups of 20 each based on their usage of mobile phones. Their ABRs were recorded and analysed for latency of waves I-V as well as interpeak latencies I-III, I-V and III-V (in ms). Results revealed no significant difference in the ABR parameters between group A (control group) and group B (subjects using mobile phones for maximum 30 min/day for 5 years). However the latency of waves was significantly prolonged in group C (subjects using mobile phones for 10 years for a maximum of 30 min/day) as compared to the control group. Based on our findings we concluded that long term exposure to mobile phones may affect conduction in the peripheral portion of the auditory pathway. However more research needs to be done to study the long term effects of mobile phones particularly of newer technologies like smart phones and 3G.

  16. The auditory brainstem response in two lizard species.

    Science.gov (United States)

    Brittan-Powell, Elizabeth F; Christensen-Dalsgaard, Jakob; Tang, Yezhong; Carr, Catherine; Dooling, Robert J

    2010-08-01

    Although lizards have highly sensitive ears, it is difficult to condition them to sound, making standard psychophysical assays of hearing sensitivity impractical. This paper describes non-invasive measurements of the auditory brainstem response (ABR) in both Tokay geckos (Gekko gecko; nocturnal animals, known for their loud vocalizations) and the green anole (Anolis carolinensis, diurnal, non-vocal animals). Hearing sensitivity was measured in 5 geckos and 7 anoles. The lizards were sedated with isoflurane, and ABRs were measured at levels of 1 and 3% isoflurane. The typical ABR waveform in response to click stimulation showed one prominent and several smaller peaks occurring within 10 ms of the stimulus onset. ABRs to brief tone bursts revealed that geckos and anoles were most sensitive between 1.6-2 kHz and had similar hearing sensitivity up to about 5 kHz (thresholds typically 20-50 dB SPL). Above 5 kHz, however, anoles were more than 20 dB more sensitive than geckos and showed a wider range of sensitivity (1-7 kHz). Generally, thresholds from ABR audiograms were comparable to those of small birds. Best hearing sensitivity, however, extended over a larger frequency range in lizards than in most bird species.

  17. Modeling Parkinson's disease falls associated with brainstem cholinergic systems decline.

    Science.gov (United States)

    Kucinski, Aaron; Sarter, Martin

    2015-04-01

    In addition to the primary disease-defining symptoms, approximately half of patients with Parkinson's disease (PD) suffer from postural instability, impairments in gait control and a propensity for falls. Consistent with evidence from patients, we previously demonstrated that combined striatal dopamine (DA) and basal forebrain (BF) cholinergic cell loss causes falls in rats traversing dynamic surfaces. Because evidence suggests that degeneration of brainstem cholinergic neurons arising from the pedunculopontine nucleus (PPN) also contributes to impaired gait and falls, here we assessed the effects of selective cholinergic PPN lesions in combination with striatal DA loss or BF cholinergic cells loss as well as losses in all 3 regions. Results indicate that all combination losses that included the BF cholinergic system slowed traversal and increased slips and falls. However, the performance of rats with losses in all 3 regions (PPN, BF, and DA) was not more severely impaired than following combined BF cholinergic and striatal DA lesions. These results confirm the hypothesis that BF cholinergic-striatal disruption of attentional-motor interactions is a primary source of falls. Additional losses of PPN cholinergic neurons may worsen posture and gait control in situations not captured by the current testing conditions. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  18. CT findings of traumatic primary brain-stem injury

    International Nuclear Information System (INIS)

    Hosaka, Yasuaki; Hatashita, Shizuo; Bandou, Kuniaki; Ueki, Yasuyuki; Abe, Kouzou; Koga, Nobunori; Sugimura, Jun; Sakakibara, Tokiwa; Takagi, Suguru

    1984-01-01

    A series of 27 consecutive patients with traumatic primary brain stem injuries was studied. They were diagnosed by means of clinical signs, neurological examination, and computerized tomography (CT). The CT findings of the brain-stem lesions were classified into 4 types: Type H, spotty, high-density; Type H and L, high- and low-densities; Type L, low-density; Type I, isodensity. The Glasgow coma scale (GCS), neurological findings on admission, CT findings (findings in the brain stem, obliteration of perimesencephalic cistern (PMC), and other findings), and the Glasgow outcome scale (GOS) were examined. In the 9 cases of Type H, there was a correlation between the GCS and the GOS, and the spotty, high-density lesions were localized mainly in the dorsal and/or ventral midbrain parenchyma, but these lesions did not show focal signs and symptoms. Without an obliteration of the PMC, Type-H patients did not always have a bad outcome. In the 4 cases of Type H and L, the 2 cases of Type L, and the 12 cases of Type I, there was an obliteration of the PMC. All of the these cases had a bad outcome (1 case of moderate disability, 3 cases of severe disability, and 14 cases of death). The mechanism producing a spotty, high-density area was discussed. The weaker impact (than the other types) and individual anatomical differences weresupposed to make for a spotty, high-density are in the brain stem. (author)

  19. Brainstem Auditory Evoked Potentials in Patients with Subarachnoid Haemorrhage

    Directory of Open Access Journals (Sweden)

    Mikhail Matveev

    2009-10-01

    Full Text Available Objective. The aim of the present study is to typify BAEPs configurations of patients with different location of lesions caused by subarachnoid haemorrhage (SAH and the ensuing complications, in view of assessing the auditory-brainstem system disturbance.Methods. The typization was performed by comparing BAEPs with standard patterns from two sets of types of BAEPs by ipsilateral and binaural stimulation and by cross-stimulation.Results. 94 BAEPs were used for collection of normal referential values: for the absolute latencies and the absolute amplitudes of waves I, II, III, IV and V; for inter-peak latencies I-III, II-III, III-V, I-V and II-V; for amplitude ratios I/V and III/V. 146 BAEPs of patients with mild SAH and 55 from patients with severe SAH, were typified. In 5 types of BAEPs out of a total of 11, the percentage of the potentials in patients with mild SAH and severe SAH differed significantly (p<0.01.Conclusions. The use of sets of types of BAEPs by ipsilateral, binaural and cross-stimulation correctly classifies the potentials in patients with mild and severe SAH.

  20. A comparison of auditory brainstem responses across diving bird species

    Science.gov (United States)

    Crowell, Sara E.; Berlin, Alicia; Carr, Catherine E.; Olsen, Glenn H.; Therrien, Ronald E.; Yannuzzi, Sally E.; Ketten, Darlene R.

    2015-01-01

    There is little biological data available for diving birds because many live in hard-to-study, remote habitats. Only one species of diving bird, the black-footed penguin (Spheniscus demersus), has been studied in respect to auditory capabilities (Wever et al., Proc Natl Acad Sci USA 63:676–680, 1969). We, therefore, measured in-air auditory threshold in ten species of diving birds, using the auditory brainstem response (ABR). The average audiogram obtained for each species followed the U-shape typical of birds and many other animals. All species tested shared a common region of the greatest sensitivity, from 1000 to 3000 Hz, although audiograms differed significantly across species. Thresholds of all duck species tested were more similar to each other than to the two non-duck species tested. The red-throated loon (Gavia stellata) and northern gannet (Morus bassanus) exhibited the highest thresholds while the lowest thresholds belonged to the duck species, specifically the lesser scaup (Aythya affinis) and ruddy duck (Oxyura jamaicensis). Vocalization parameters were also measured for each species, and showed that with the exception of the common eider (Somateria mollisima), the peak frequency, i.e., frequency at the greatest intensity, of all species' vocalizations measured here fell between 1000 and 3000 Hz, matching the bandwidth of the most sensitive hearing range.

  1. Progranulin expression in advanced human atherosclerotic plaque.

    Science.gov (United States)

    Kojima, Yoji; Ono, Koh; Inoue, Katsumi; Takagi, Yasushi; Kikuta, Ken-ichiro; Nishimura, Masaki; Yoshida, Yoshinori; Nakashima, Yasuhiro; Matsumae, Hironobu; Furukawa, Yutaka; Mikuni, Nobuhiro; Nobuyoshi, Masakiyo; Kimura, Takeshi; Kita, Toru; Tanaka, Makoto

    2009-09-01

    Progranulin (PGRN) is a unique growth factor that plays an important role in cutaneous wound healing. It has an anti-inflammatory effect and promotes cell proliferation. However, when it is degraded to granulin peptides (GRNs) by neutrophil proteases, a pro-inflammatory reaction occurs. Since injury, inflammation and repair are common features in the progression of atherosclerosis, it is conceivable that PGRN plays a role in atherogenesis. Immunohistochemical analysis of human carotid endoatherectomy specimens indicated that vascular smooth muscle cells (vSMCs) in the intima expressed PGRN. Some macrophages in the plaque also expressed PGRN. We assessed the effect of PGRN on a human monocytic leukemia cell line (THP-1) and human aortic smooth muscle cells (HASMCs). PGRN alone had no effect on HASMC or THP-1 proliferation or migration. However, when THP-1 cells were stimulated with MCP-1, the number of migrated cells decreased in a PGRN-dose-dependent manner. TNF-alpha-induced HASMC migration was enhanced only at 10nM of PGRN. Interleukin-8 (IL-8) secretion from HASMCs was reduced by forced expression of PGRN and increased by RNAi-mediated knockdown of PGRN. While exogenous treatment with recombinant PGRN decreased IL-8 secretion, degraded recombinant GRNs increased IL-8 secretion from HASMCs. The expression of PGRN mainly reduces inflammation and its degradation into GRNs enhances inflammation in atherosclerotic plaque and may contribute to the progression of atherosclerosis.

  2. Auditory brainstem activity and development evoked by apical versus basal cochlear implant electrode stimulation in children.

    Science.gov (United States)

    Gordon, K A; Papsin, B C; Harrison, R V

    2007-08-01

    The role of apical versus basal cochlear implant electrode stimulation on central auditory development was examined. We hypothesized that, in children with early onset deafness, auditory development evoked by basal electrode stimulation would differ from that evoked more apically. Responses of the auditory nerve and brainstem, evoked by an apical and a basal implant electrode, were measured over the first year of cochlear implant use in 50 children with early onset severe to profound deafness who used hearing aids prior to implantation. Responses at initial stimulation were of larger amplitude and shorter latency when evoked by the apical electrode. No significant effects of residual hearing or age were found on initial response amplitudes or latencies. With implant use, responses evoked by both electrodes showed decreases in wave and interwave latencies reflecting decreased neural conduction time through the brainstem. Apical versus basal differences persisted with implant experience with one exception; eIII-eV interlatency differences decreased with implant use. Acute stimulation shows prolongation of basally versus apically evoked auditory nerve and brainstem responses in children with severe to profound deafness. Interwave latencies reflecting neural conduction along the caudal and rostral portions of the brainstem decreased over the first year of implant use. Differences in neural conduction times evoked by apical versus basal electrode stimulation persisted in the caudal but not rostral brainstem. Activity-dependent changes of the auditory brainstem occur in response to both apical and basal cochlear implant electrode stimulation.

  3. Analysis of diffuse brain injury with primary brainstem lesion on MRI

    International Nuclear Information System (INIS)

    Shibata, Masayoshi; Matsumae, Mitsunori; Shimoda, Masami; Ishizaka, Hideo; Shiramizu, Hideki; Morita, Seiji; Tsugane, Ryuichi

    2003-01-01

    It has been reported that diffuse brain injury patients with primary brainstem lesions have a poor prognosis. Predicting the existence of brainstem injury at hospital arrival is problematic in actual clinical practice. We conducted magnetic resonance imaging (MRI), to visualize brainstem lesions clearly, and retrospectively analyzed predictive factors of brainstem lesions by stepwise multiple logistic regression analysis of patient characteristics, neurological findings, laboratory data, and CT findings at arrival in each case. We compared 24 patients with brainstem lesion and 60 without using MRI obtained less than 3 weeks after admission. Items investigated were blood pressure immediately after hospital arrival, arterial blood gas analysis, existence of abnormal respiration, blow direction, Glasgow coma scale (GCS), light reflex, oculocephalic reflex, corneal reflex, intracranial pressure, jugular venous oxygen saturation, and CT findings such as existence of subarachnoid hemorrhage at the suprasellar cistern, perimesencephalic cistern and convexity, lesions on the thalamus and basal ganglia, gliding contusion, intraventricular hemorrhage and Traumatic Coma Data Bank classification. Independent predictive factors of primary brainstem lesion included impaired light reflex (odds ratio: 2.269), subarachnoid hemorrhage at convexity (odds ratio: 3.592) and suprasellar cistern (odds ratio: 2.458), and Traumatic Coma Data Bank group III (odds ratio: 11.062). (author)

  4. Newborn hearing screening with transient evoked otoacoustic emissions and automatic auditory brainstem response

    Directory of Open Access Journals (Sweden)

    Renata Mota Mamede de Carvallo

    2008-09-01

    Full Text Available Objective: The aim of the present investigation was to check Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response tests applied together in regular nurseries and Newborn Intensive Care Units (NICU, as well as to describe and compare the results obtained in both groups. Methods: We tested 150 newborns from regular nurseries and 70 from NICU. Rresults: The newborn hearing screening results using Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response tests could be applied to all babies. The “pass” result for the group of babies from the nursery was 94.7% using Transient Evoked Otoacoustic Emissions and 96% using Automatic Auditory Brainstem Response. The newborn intensive care unit group obtained 87.1% on Transient Evoked Otoacoustic Emissions and 80% on the Automatic Auditory Brainstem Response, and there was no statistical difference between the procedures when the groups were evaluated individually. However, comparing the groups, Transient Evoked Otoacoustic Emissions were presented in 94.7% of the nursery babies and in 87.1% in the group from the newborn intensive care unit. Considering the Automatic Auditory Brainstem Response, we found 96 and 87%, respectively. Cconclusions: Transient Evoked Otoacoustic Emissions and Automatic Auditory Brainstem Response had similar “pass” and “fail” results when the procedures were applied to neonates from the regular nursery, and the combined tests were more precise to detect hearing impairment in the newborn intensive care unit babies.

  5. A clinical study of brainstem infarction identified on magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Masaki; Takahashi, Akira (Nagoya Univ. (Japan). Faculty of Medicine); Arahata, Yutaka; Motegi, Yoshimasa; Furuse, Masahiro

    1993-04-01

    We conducted a clinical study of 155 cases that were confirmed to have brainstem infarctions on MRI (T[sub 1]-weighted image showed a low signal and T[sub 2]-weighted image showed a high signal, measuring in excess of 2 x 2 mm). The majority of the brainstem infarction was located in the pontine base in 132 cases (85.2%). Of these, 19 cases had double lesions including infarctions in the pontine base. Second infarctions frequently occurred in the cerebral peduncle or medical medulla oblongata, unilateral to the pontine infarctions. In addition to 98 symptomatic cases, there were 57 cases of 'asymptomatic' brainstem infarction. They comprised 24 cases accompanying other symptomatic cerebrovascular diseases in the supratentorium and 33 cases of transient subjective complaints such as headache or vertigo-dizziness. Complication by supratentorial infarctions was significantly frequent in cases of brainstem infarction (p<0.001), 122 of 155 cases (78.7%), especially in the pontine base (88.6%); while in the control cases (without brainstem infarction) only 65 of 221 cases (29.4%). These findings are considered to show the widespread progress of arteriosclerosis in brainstem infarction, especially in ones in the pontine base. (author).

  6. [Distribution of human enterovirus 71 in brainstem of infants with brain stem encephalitis and infection mechanism].

    Science.gov (United States)

    Hao, Bo; Gao, Di; Tang, Da-Wei; Wang, Xiao-Guang; Liu, Shui-Ping; Kong, Xiao-Ping; Liu, Chao; Huang, Jing-Lu; Bi, Qi-Ming; Quan, Li; Luo, Bin

    2012-04-01

    To explore the mechanism that how human enterovirus 71 (EV71) invades the brainstem and how intercellular adhesion molecules-1 (ICAM-1) participates by analyzing the expression and distribution of human EV71, and ICAM-1 in brainstem of infants with brain stem encephalitis. Twenty-two brainstem of infants with brain stem encephalitis were collected as the experimental group and 10 brainstems of fatal congenital heart disease were selected as the control group. The sections with perivascular cuffings were selected to observe EV71-VP1 expression by immunohistochemistry method and ICAM-1 expression was detected for the sections with EV71-VP1 positive expression. The staining image analysis and statistics analysis were performed. The experiment and control groups were compared. (1) EV71-VP1 positive cells in the experimental group were mainly astrocytes in brainstem with nigger-brown particles, and the control group was negative. (2) ICAM-1 positive cells showed nigger-brown. The expression in inflammatory cells (around blood vessels of brain stem and in glial nodules) and gliocytes increased. The results showed statistical difference comparing with control group (P diagnose fatal EV71 infection in infants. EV71 can invade the brainstem via hematogenous route. ICAM-1 may play an important role in the pathogenic process.

  7. Release of mineral ions in dental plaque following acid production.

    Science.gov (United States)

    Tanaka, M; Margolis, H C

    1999-03-01

    The release of appreciable amounts of calcium, phosphate and fluoride found in whole plaque into the plaque-fluid phase, following bacterial acid production, can potentially reduce the driving force for tooth demineralization. However, limited information is available on this topic, particularly on the release of fluoride. This study sought to determine the change in calcium, phosphate and fluoride concentrations in plaque fluid after sucrose exposure. 48 h overnight-fasted supragingival plaque samples were collected from all tooth surfaces (with the exception of the lower lingual anterior teeth) of one half of an individual mouth, following a 1 min water rinse. Plaque samples were then collected from the other half of the same mouth, following a 292 mM sucrose rinse. Plaque fluid was isolated by centrifugation and analysed for total calcium and phosphate (ion chromatography) and for free fluoride (ion-specific electrode). Samples were collected from seven individuals. Following sucrose exposure, plaque-fluid pH decreased significantly from 6.5+/- 0.3 to 5.4+/-0.2; calcium concentrations (mmol/l) also increased significantly (p Fluoride and phosphate concentrations in plaque fluid, however, did not increase significantly after sucrose exposure: mean concentrations (mmol/l) of fluoride after the water and sucrose rinses were 0.006+/-0.003 and 0.005+/-0.002, respectively, and mean phosphate concentrations (mmol/l) were 11.0+/-2.0 and 12.0+/-3.0, respectively. When results were expressed per wet plaque weight, phosphate concentrations were also found to increase significantly. The same trends were observed when additional plaque samples were treated in vitro with sucrose: fluoride-ion activity did not increase in plaque under in vivo-like conditions.

  8. Plaque removal efficacy of Colgate 360 toothbrush: A clinical study

    Directory of Open Access Journals (Sweden)

    Nageshwar Iyer

    2016-01-01

    Full Text Available Aim: The aim of this clinical study was to confirm the plaque removal efficacy of the Colgate 360 Whole Mouth Clean Toothbrush. Study Design: This was a single-center, monadic, case-controlled study with the 7 days duration. Materials and Methods: A total of eighty participants (56 male and 24 female aged between 18 and 45 years with a minimum of 20 permanent teeth (excluding the third molars without any prosthetic crowns and an initial plaque score of minimum 1.5 as determined by Modified Quigley-Hein Plaque Index (1970 participated in the study. There were two dropouts during the study duration, one male and one female. The participants were instructed to brush for 1 min, after which plaque index was recorded again. They were then instructed to brush their teeth twice a day for 1 min with the assigned toothbrush (Colgate 360 Whole Mouth Clean Toothbrush and a commercially available fluoride toothpaste for the next 7 days. On the 7 th day, all the participants were recalled for follow-up and plaque examination. The plaque index scores (pre- and post-brushing were recorded, tabulated, and analyzed statistically. Results: The mean plaque indices reduced after brushing both on day 1 and day 7. There was also a reduction in mean plaque indices from day 1 to day 7. All these reductions were statistically significant (P < 0.001. The reduction in plaque scores was independent of the gender of the participants however female participants showed lower scores as compared to male participants (P < 0.001. Conclusion: The present study demonstrated a significant reduction in plaque scores with the use of Colgate 360 Whole Mouth Clean Soft Toothbrush throughout the study period. Continued use resulted in a further significant reduction in plaque scores irrespective of the gender of participants.

  9. Development of UO{sub 2}-Stainless Steel Fuel Plates Containing 30-50 Vol. % Oxide; Fabrication de plaques de combustible en acier inoxydable-UO{sub 2} contenant 30 a 40% d'oxyde (en volume); Razrabotka toplivnykh ehlementov iz nerzhaveyushchej stali i UO{sub 2}, soderzhashchikh 30 - 50 OB.% okisi; Elaboracion de placas de combustible de acero inoxidable UO{sub 2} conteniendo 30 a 40% de oxido (en volumen)

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, H. [Atomic Energy Research Establishment, Harwell (United Kingdom)

    1963-11-15

    This paper describes developments associated with the fabrication of UO{sub 2}-stainless steel plate type fuel elements containing up to 50 vol.% UO{sub 2}. The preparation of high-density spherical UO{sub 2} sintered particles in the 100- to 500-{mu}m size range and the compacting and sintering of cermet plate cores with the particles uniformly distributed in the stainless steel matrix are described together with procedures for hot roll-bonding the fuel plates. Rolling at temperatures up to 1300{sup o}C using total deformations in the 40% to 90% range were studied to establish optimum conditions for the production of high-density cores and to achieve good bonding between the plate components with minimum fragmentation and stringering of the UO{sub 2} particles. The manufacture of large fuel plates utilizing multi-core plates which are bonded together during hot rolling is also described. Data are presented on the mechanical properties of 30, 40 and 50 vol.% UO{sub 2}-stainless steel cermets, prepared as described above, and tested in the as ''rolled'' and annealed condition at various temperatures up to 700{sup o}C, using specimens taken laterally and longitudinally to the direction of rolling. The influence of size and uniformity of distribution of the UO{sub 2} spheres on consistency of mechanical properties are discussed. The strength of bonding between core and cladding for similar cermets in the same temperature range was also assessed. Results are also included of thermal cycling tests between 50 and 800{sup o}C, which was done to study the effects on bond stability and cermet structure after 100, 500 and 1000 cycles. (author) [French] L'auteur expose le processus de fabrication d'elements de combustible UO{sub 2}-Inox en plaques contenant jusqu'a 50% en volume d'UO{sub 2}; il decrit la preparation de particules spheriques de UO{sub 2} frittees de densite elevee (taille dans la gamme de 100 a 500), le pressage et le frittage des plaques de cermet dans

  10. Low gray scale values of computerized images of carotid plaques associated with increased levels of triglyceride-rich lipoproteins and with increased plaque lipid content

    DEFF Research Database (Denmark)

    Grønholdt, Marie-Louise M.; Nordestgaard, Børge; Weibe, Britt M.

    1997-01-01

    Relatioin between low gray scale values in computerized images of carotid plaques and 1) plasma levels of triglyceride-rich lipoproteins and 2) plaque lipid content......Relatioin between low gray scale values in computerized images of carotid plaques and 1) plasma levels of triglyceride-rich lipoproteins and 2) plaque lipid content...

  11. Bacterial colonization of psoriasis plaques. Is it relevant?

    Directory of Open Access Journals (Sweden)

    Eva Marcus

    2011-08-01

    Full Text Available Bacterial colonization was investigated retrospectively in patients with plaque psoriasis (n=98 inpatient treatments, n=73 patients. At least one pathogen was found in 46% of all cases. Staphylococcus aureus was the most frequent bacterium. Bacterial colonization of psoriasis plaques could be relevant in individual cases.

  12. New low-viscosity overlay medium for viral plaque assays

    Directory of Open Access Journals (Sweden)

    Garten Wolfgang

    2006-08-01

    Full Text Available Abstract Background Plaque assays in cell culture monolayers under solid or semisolid overlay media are commonly used for quantification of viruses and antiviral substances. To overcome the pitfalls of known overlays, we tested suspensions of microcrystalline cellulose Avicel RC/CL™ as overlay media in the plaque and plaque-inhibition assay of influenza viruses. Results Significantly larger plaques were formed under Avicel-containing media, as compared to agar and methylcellulose (MC overlay media. The plaque size increased with decreasing Avicel concentration, but even very diluted Avicel overlays (0.3% ensured formation of localized plaques. Due to their low viscosity, Avicel overlays were easier to use than methylcellulose overlays, especially in the 96-well culture plates. Furthermore, Avicel overlay could be applied without prior removal of the virus inoculum thus facilitating the assay and reducing chances of cross-contamination. Using neuraminidase inhibitor oseltamivir carboxylate, we demonstrated applicability of the Avicel-based plaque reduction assay for testing of antiviral substances. Conclusion Plaque assay under Avicel-containing overlay media is easier, faster and more sensitive than assays under agar- and methylcellulose overlays. The assay can be readily performed in a 96-well plate format and seems particularly suitable for high-throughput virus titrations, serological studies and experiments on viral drug sensitivity. It may also facilitate work with highly pathogenic agents performed under hampered conditions of bio-safety labs.

  13. Intravascular Photoacoustic Imaging : A New Tool for Vulnerable Plaque Identification

    NARCIS (Netherlands)

    Jansen, K.; Van Soest, G.; Van der Steen, A.F.W.

    2014-01-01

    The vulnerable atherosclerotic plaque is believed to be at the root of the majority of acute coronary events. Even though the exact origins of plaque vulnerability remain elusive, the thin-cap fibroatheroma, characterized by a lipid-rich necrotic core covered by a thin fibrous cap, is considered to

  14. Clear Plaque Mutants of Lactococcal Phage TP901-1

    DEFF Research Database (Denmark)

    Kot, Witold; Kilstrup, Mogens; Vogensen, Finn K.

    2016-01-01

    We report a method for obtaining turbid plaques of the lactococcal bacteriophage TP901-1 and its derivative TP901-BC1034. We have further used the method to isolate clear plaque mutants of this phage. Analysis of 8 such mutants that were unable to lysogenize the host included whole genome...

  15. Urease and Dental Plaque Microbial Profiles in Children.

    Science.gov (United States)

    Morou-Bermudez, Evangelia; Rodriguez, Selena; Bello, Angel S; Dominguez-Bello, Maria G

    2015-01-01

    Urease enzymes produced by oral bacteria generate ammonia, which can have a significant impact on the oral ecology and, consequently, on oral health. To evaluate the relationship of urease with dental plaque microbial profiles in children as it relates to dental caries, and to identify the main contributors to this activity. 82 supragingival plaque samples were collected from 44 children at baseline and one year later, as part of a longitudinal study on urease and caries in children. DNA was extracted; the V3-V5 region of the 16S rRNA gene was amplified and sequenced using 454 pyrosequencing. Urease activity was measured using a spectrophotometric assay. Data were analyzed with Qiime. Plaque urease activity was significantly associated with the composition of the microbial communities of the dental plaque (Baseline P = 0.027, One Year P = 0.012). The bacterial taxa whose proportion in dental plaque exhibited significant variation by plaque urease levels in both visits were the family Pasteurellaceae (Baseline Purease and positively associated with dental caries (Bonferroni Purease enzymes primarily from species in the family Pasteurellaceae can be an important ecological determinant in children's dental plaque. Further studies are needed to establish the role of urease-associated bacteria in the acid/base homeostasis of the dental plaque, and in the development and prediction of dental caries in children.

  16. Vulnerable plaque detection: The role of 18-fluorine ...

    African Journals Online (AJOL)

    Positron emission tomography computed tomography (PET-CT) is a combined functional and structural multi modality imaging tool that can be utilized to detect vulnerable and atherosclerotic plaques. In this study we observe the prevalence of active and calcified plaques in selected arteries during whole-body 18F-FDG ...

  17. Spectral CT of carotid atherosclerotic plaque: comparison with histology

    Energy Technology Data Exchange (ETDEWEB)

    Zainon, R.; Doesburg, R.M. [University of Canterbury, Department of Physics and Astronomy, Christchurch (New Zealand); Ronaldson, J.P.; Gieseg, S.P. [University of Otago, Centre for Bioengineering, Christchurch (New Zealand); Janmale, T. [University of Canterbury, Free Radical Biochemistry Laboratory, School of Biological Sciences, Christchurch (New Zealand); Scott, N.J. [University of Otago, Department of Medicine, Christchurch (New Zealand); Buckenham, T.M. [University of Otago, Department of Academic Radiology, Christchurch (New Zealand); Butler, A.P.H. [University of Otago, Centre for Bioengineering, Christchurch (New Zealand); University of Otago, Department of Academic Radiology, Christchurch (New Zealand); University of Canterbury, Department of Electrical and Computer Engineering, Christchurch (New Zealand); European Organisation for Nuclear Research (CERN), Geneva (Switzerland); Butler, P.H. [University of Canterbury, Department of Physics and Astronomy, Christchurch (New Zealand); European Organisation for Nuclear Research (CERN), Geneva (Switzerland); Roake, J.A. [Christchurch Hospital, Department of Vascular, Endovascular and Transplant Surgery, Christchurch (New Zealand); Anderson, N.G. [University of Otago, Centre for Bioengineering, Christchurch (New Zealand); University of Otago, Department of Academic Radiology, Christchurch (New Zealand); University of Otago, Christchurch, Department of Radiology, PO Box 4345, Christchurch (New Zealand)

    2012-12-15

    To distinguish components of vulnerable atherosclerotic plaque by imaging their energy response using spectral CT and comparing images with histology. After spectroscopic calibration using phantoms of plaque surrogates, excised human carotid atherosclerotic plaques were imaged using MARS CT using a photon-processing detector with a silicon sensor layer and microfocus X-ray tube (50 kVp, 0.5 mA) at 38-{mu}m voxel size. The plaques were imaged, sectioned and re-imaged using four threshold energies: 10, 16, 22 and 28 keV; then sequentially stained with modified Von Kossa, Perl's Prussian blue and Oil-Red O, and photographed. Relative Hounsfield units across the energies were entered into a linear algebraic material decomposition model to identify the unknown plaque components. Lipid, calcium, iron and water-like components of plaque have distinguishable energy responses to X-ray, visible on spectral CT images. CT images of the plaque surface correlated very well with histological photographs. Calcium deposits (>1,000 {mu}m) in plaque are larger than iron deposits (<100 {mu}m), but could not be distinguished from each other within the same voxel using the energy range available. Spectral CT displays energy information in image form at high spatial resolution, enhancing the intrinsic contrast of lipid, calcium and iron within atheroma. (orig.)

  18. Chronic plaque psoriasis | Luba | South African Family Practice

    African Journals Online (AJOL)

    Chronic plaque psoriasis, the most common form of psoriasis, is a papulosquamous disease defined by erythematous plaques with a silvery scale. The diagnosis usually is clinical, but occasionally a biopsy is necessary. Psoriasis affects 0.6 to 4.8 percent of the U.S. population, and about 30 percent of affected patients have ...

  19. Lysophosphatidic acid triggers mast cell-driven atherosclerotic plaque destabilization by increasing vascular inflammation.

    NARCIS (Netherlands)

    Bot, M.; , van, Berkel T.J.C.

    2013-01-01

    Lysophosphatidic acid (LPA), a bioactive lysophospholipid, accumulates in the atherosclerotic plaque. It has the capacity to activate mast cells, which potentially exacerbates plaque progression. In this study, we thus aimed to investigate whether LPA contributes to plaque destabilization by

  20. Emerging Technology Update Intravascular Photoacoustic Imaging of Vulnerable Atherosclerotic Plaque.

    Science.gov (United States)

    Wu, Min; Fw van der Steen, Antonius; Regar, Evelyn; van Soest, Gijs

    2016-10-01

    The identification of vulnerable atherosclerotic plaques in the coronary arteries is emerging as an important tool for guiding atherosclerosis diagnosis and interventions. Assessment of plaque vulnerability requires knowledge of both the structure and composition of the plaque. Intravascular photoacoustic (IVPA) imaging is able to show the morphology and composition of atherosclerotic plaque. With imminent improvements in IVPA imaging, it is becoming possible to assess human coronary artery disease in vivo . Although some challenges remain, IVPA imaging is on its way to being a powerful tool for visualising coronary atherosclerotic features that have been specifically associated with plaque vulnerability and clinical syndromes, and thus such imaging might become valuable for clinical risk assessment in the catheterisation laboratory.

  1. Immunofluorescence Plaque Assay for African Swine Fever Virus

    Science.gov (United States)

    Tessler, J.; Hess, W. R.; Pan, I. C.; Trautman, R.

    1974-01-01

    Suitably diluted cell culture adapted African swine fever virus preparations were inoculated on VERO cell monolayers and grown on coverslips. Gum tragacanth was used as an overlay. After three days incubation at 37°C the infected cultures were fixed with acetone and stained with fluorescent antibody conjugate. Fluorescing plaques consisted of 20-30 infected cells. Three statistical criteria for a quantitatively reliable assay were met: the Poisson distribution for plaque counts, linearity of the relationship between the concentration of virus and the plaque count and reproducibility of replicate titrations. The method is suitable for counts up to at least 70 plaques per 5 cm2 coverslip and computed titers are reproducible within 0.16 log units with a total of 300 plaques enumerated. PMID:4279763

  2. Plaque biology: interesting science or pharmacological treasure trove?

    Science.gov (United States)

    Loftus, I; Thompson, M

    2008-11-01

    Our understanding of the events that occur within atherosclerotic plaques has improved dramatically over the last 2 decades, particularly with regard to the role of plaque destabilisation and the onset of clinical ischaemic syndromes. Many potential targets have been identified for therapeutic intervention aimed at disease prevention, plaque stabilisation and regression. Furthermore, many potential biomarkers of vascular disease have generated interest in terms of monitoring disease activity and the effect of therapeutic agents. However, despite much scientific promise with in vitro cell and animal models, there has been much less success in modulation of these processes in clinical practice. This review will highlight the local and systemic factors associated with disease progression and acute plaque destabilisation, the current role of therapeutic agents and the potential for targeted plaque modification.

  3. Experiences from Auditory Brainstem Implantation (ABIs) in four paediatric patients.

    Science.gov (United States)

    Lundin, Karin; Stillesjö, Fredrik; Nyberg, Gunnar; Rask-Andersen, Helge

    2016-01-01

    Indications for auditory brainstem implants (ABIs) have been widened from patients with neurofibromatosis type 2 (NF2) to paediatric patients with congenital cochlear malformations, cochlear nerve hypoplasia/aplasia, or cochlear ossification after meningitis. We present four ABI surgeries performed in children at Uppsala University Hospital in Sweden since 2009. Three children were implanted with implants from Cochlear Ltd. (Lane Cove, Australia) and one child with an implant from MedEl GMBH (Innsbruck, Austria). A boy with Goldenhar syndrome was implanted with a Cochlear Nucleus ABI24M at age 2 years (patient 1). Another boy with CHARGE syndrome was implanted with a Cochlear Nucleus ABI541 at age 2.5 years (patient 2). Another boy with post-ossification meningitis was implanted with a Cochlear Nucleus ABI24M at age 4 years (patient 3). A girl with cochlear aplasia was implanted with a MedEl Synchrony ABI at age 3 years (patient 4). In patients 1, 2, and 3, the trans-labyrinthine approach was used, and in patient 4 the retro-sigmoid approach was used. Three of the four children benefited from their ABIs and use it full time. Two of the full time users had categories of auditory performance (CAP) score of 4 at their last follow up visit (6 and 2.5 years postoperative) which means they can discriminate consistently any combination of two of Ling's sounds. One child has not been fully evaluated yet, but is a full time user and had CAP 2 (responds to speech sounds) after 3 months of ABI use. No severe side or unpleasant stimulation effects have been observed so far. There was one case of immediate electrode migration and one case of implant device failure after 6.5 years. ABI should be considered as an option in the rehabilitation of children with similar diagnoses.

  4. Brainstem auditory-evoked potential in Boxer dogs

    Directory of Open Access Journals (Sweden)

    Mariana Isa Poci Palumbo

    2014-10-01

    Full Text Available Brainstem auditory-evoked potential (BAEP has been widely used for different purposes in veterinary practice and is commonly used to identify inherited deafness and presbycusis. In this study, 43 Boxer dogs were evaluated using the BAEP. Deafness was diagnosed in 3 dogs (2 bilateral and 1 unilateral allowing the remaining 40 Boxers to be included for normative data analysis including an evaluation on the influence of age on the BAEP. The animals were divided into 2 groups of 20 Boxers each based on age. The mean age was 4.54 years (range, 1-8 in group I, and 9.83 years (range, 8.5-12 in group II. The mean latency for I, III, and V waves were 1.14 (±0.07, 2.64 (±0.11, and 3.48 (±0.10 ms in group I, and 1.20 (±0.12, 2.73 (±0.15, and 3.58 (±0.22 ms in group II, respectively. The mean inter-peak latencies for the I-III, III-V and I-V intervals were 1.50 (±0.15, 0.84 (±0.15, and 2.34 (±0.11 ms in group I, and 1.53 (±0.16, 0.85 (±0.15, and 2.38 (±0.19 ms in group II, respectively. Latencies of waves I and III were significant different between group I and II. For the I-III, III-V and I-V intervals, no significant differences were observed between the 2 groups. As far as we know, this is the first normative study of BAEP obtained from Boxer dogs.

  5. Localization of the brainstem GABAergic neurons controlling paradoxical (REM sleep.

    Directory of Open Access Journals (Sweden)

    Emilie Sapin

    Full Text Available Paradoxical sleep (PS is a state characterized by cortical activation, rapid eye movements and muscle atonia. Fifty years after its discovery, the neuronal network responsible for the genesis of PS has been only partially identified. We recently proposed that GABAergic neurons would have a pivotal role in that network. To localize these GABAergic neurons, we combined immunohistochemical detection of Fos with non-radioactive in situ hybridization of GAD67 mRNA (GABA synthesis enzyme in control rats, rats deprived of PS for 72 h and rats allowed to recover after such deprivation. Here we show that GABAergic neurons gating PS (PS-off neurons are principally located in the ventrolateral periaqueductal gray (vlPAG and the dorsal part of the deep mesencephalic reticular nucleus immediately ventral to it (dDpMe. Furthermore, iontophoretic application of muscimol for 20 min in this area in head-restrained rats induced a strong and significant increase in PS quantities compared to saline. In addition, we found a large number of GABAergic PS-on neurons in the vlPAG/dDPMe region and the medullary reticular nuclei known to generate muscle atonia during PS. Finally, we showed that PS-on neurons triggering PS localized in the SLD are not GABAergic. Altogether, our results indicate that multiple populations of PS-on GABAergic neurons are distributed in the brainstem while only one population of PS-off GABAergic neurons localized in the vlPAG/dDpMe region exist. From these results, we propose a revised model for PS control in which GABAergic PS-on and PS-off neurons localized in the vlPAG/dDPMe region play leading roles.

  6. Dental plaque removal with a novel battery-powered toothbrush.

    Science.gov (United States)

    Biesbrock, Aaron R; Walters, Patricia; Bartizek, Robert D; Ruhlman, Douglas; Donly, Kevin J

    2002-04-01

    To compare the plaque removal efficacy of a positive control power toothbrush (Oral-B Ultra Plaque Remover) to an experimental power toothbrush (Crest SpinBrush) following a single use. This study was a randomized, controlled, examiner-blind, 2-period crossover design which examined plaque removal with the two toothbrushes following a single use in 38 completed subjects. Plaque was scored before and after brushing using the Turesky Modification of the Quigley-Hein Index. Baseline plaque scores were 1.89 and 1.91 for the experimental toothbrush and control toothbrush treatment groups, respectively. With respect to all surfaces examined, the experimental toothbrush delivered an adjusted (via analysis of covariance) mean difference between baseline and post-brushing plaque scores of 0.46 while the control toothbrush delivered an adjusted mean difference of 0.45. These results were not statistically significant (P=0.645). A 95% one-sided upper confidence limit on the Ultra Plaque Remover minus SpinBrush difference in amount of plaque removed was calculated as 9.4% of the Ultra Plaque Remover adjusted mean. A common criterion for what is known as an "at least as good as" test is that the 95% one-sided confidence limit on the product difference is below 10% of the control product mean. Using this criterion, the SpinBrush is at least as good as the Oral-B Ultra Plaque Remover. With respect to buccal and lingual surfaces, the experimental toothbrush delivered very similar results relative to the control toothbrush. These results were also not statistically significant (P> 0.564).

  7. Monte Carlo generation of dosimetric parameters for eye plaque dosimetry

    International Nuclear Information System (INIS)

    Cutajar, D.L.; Green, J.A.; Guatelli, S.; Rosenfeld, A.B.

    2010-01-01

    Full text: The Centre for Medical Radiation Physics have undertaken the dcvelopment of a quality assurance tool, using silicon pixelated detectors, for the calibration of eye plaques prior to insertion. Dosimetric software to correlate the measured and predicted dose rates has been constructed. The dosimetric parameters within the software, for both 1-125 and Ru-I 06 based eye plaques, were optimised using the Geant4 Monte Carlo toolkit. Methods For 1-125 based plaques, an novel application was developed to generate TG-43 parameters for any seed input. TG-43 parameters were generated for an Oncura model 6711 seed, with data points every millimetre up to 25 mm in the radial direction, and every 5 degrees in polar angle, and correlated to published data. For the Ru106 based plaques, an application was developed to generate dose rates about a Bebig model CCD plaque. Toroids were used to score the deposited dose, taking advantage of the cylindrical symmetry of the plaque, with radii in millimetre increments up to 25 mm, and depth from the plaque surface in millimetre increments up to 25 mm. Results TheTG43 parameters generated for the 6711 seed correlate well with published TG43 data at the given intervals, with radial dose function within 3%, and anisotropy function within 5% for angles greater than 30 degrees. The Ru-l 06 plaque data correlated well with the Bebig protocol of measurement. Conclusion Geant4 is a useful Monte Carlo tool for the generation of dosimetric data for eye plaque dosimetry. which may improve the quality assurance of eye plaque treatment. (author)

  8. Gender differences in binaural speech-evoked auditory brainstem response: are they clinically significant?

    Science.gov (United States)

    Jalaei, Bahram; Azmi, Mohd Hafiz Afifi Mohd; Zakaria, Mohd Normani

    2018-05-17

    Binaurally evoked auditory evoked potentials have good diagnostic values when testing subjects with central auditory deficits. The literature on speech-evoked auditory brainstem response evoked by binaural stimulation is in fact limited. Gender disparities in speech-evoked auditory brainstem response results have been consistently noted but the magnitude of gender difference has not been reported. The present study aimed to compare the magnitude of gender difference in speech-evoked auditory brainstem response results between monaural and binaural stimulations. A total of 34 healthy Asian adults aged 19-30 years participated in this comparative study. Eighteen of them were females (mean age=23.6±2.3 years) and the remaining sixteen were males (mean age=22.0±2.3 years). For each subject, speech-evoked auditory brainstem response was recorded with the synthesized syllable /da/ presented monaurally and binaurally. While latencies were not affected (p>0.05), the binaural stimulation produced statistically higher speech-evoked auditory brainstem response amplitudes than the monaural stimulation (p0.80), substantive gender differences were noted in most of speech-evoked auditory brainstem response peaks for both stimulation modes. The magnitude of gender difference between the two stimulation modes revealed some distinct patterns. Based on these clinically significant results, gender-specific normative data are highly recommended when using speech-evoked auditory brainstem response for clinical and future applications. The preliminary normative data provided in the present study can serve as the reference for future studies on this test among Asian adults. Copyright © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

  9. Neonatal neurological disorders involving the brainstem: neurosonographic approaches through the squamous suture and the foramen magnum

    International Nuclear Information System (INIS)

    Tu, Yi-Fang; Chen, Cheng-Yu; Lin, Yuh-Jey; Chang, Ying-Chao; Huang, Chao-Ching

    2005-01-01

    Brainstem damage which often indicates a critical condition is usually underestimated by trans-anterior-fontanel neurosonography (NS) owing to the far-field limitations. Instead, NS alternately scanning through the squamous suture of the temporal bones and the foramen magnum could provide a better visualization of the brainstem structures. The NS characteristics of brainstem lesions caused by various neonatal neurological disorders, such as hypoxic-ischemic encephalopathy (HIE), metabolic encephalopathy, birth trauma and bacterial meningoencephalitis, can be depicted at the acute stage. An echogenic change in the midbrain was found in patients with HIE or metabolic encephalopathy. In addition to the echogenic change, bilateral transtentorial temporal lobe herniation distorting the contour of the midbrain was observed in a patient with group B streptococcus meningoencephalitis, whereas echogenic changes at the level of the pons and/or the medulla oblongata, mainly localized in the dorsal part, could be observed in newborns with severe HIE, maple syrup urine disease or birth trauma. In this pictorial assay, we demonstrate the feasibility of NS imaging in evaluating the entire brainstem structure of critically ill neonates in the near field and illustrate the characteristic features of brainstem involvement in various neonatal neurological disorders along with computed tomography or magnetic resonance imaging correlation. (orig.)

  10. Impairments in musical abilities reflected in the auditory brainstem: evidence from congenital amusia.

    Science.gov (United States)

    Lehmann, Alexandre; Skoe, Erika; Moreau, Patricia; Peretz, Isabelle; Kraus, Nina

    2015-07-01

    Congenital amusia is a neurogenetic condition, characterized by a deficit in music perception and production, not explained by hearing loss, brain damage or lack of exposure to music. Despite inferior musical performance, amusics exhibit normal auditory cortical responses, with abnormal neural correlates suggested to lie beyond auditory cortices. Here we show, using auditory brainstem responses to complex sounds in humans, that fine-grained automatic processing of sounds is impoverished in amusia. Compared with matched non-musician controls, spectral amplitude was decreased in amusics for higher harmonic components of the auditory brainstem response. We also found a delayed response to the early transient aspects of the auditory stimulus in amusics. Neural measures of spectral amplitude and response timing correlated with participants' behavioral assessments of music processing. We demonstrate, for the first time, that amusia affects how complex acoustic signals are processed in the auditory brainstem. This neural signature of amusia mirrors what is observed in musicians, such that the aspects of the auditory brainstem responses that are enhanced in musicians are degraded in amusics. By showing that gradients of music abilities are reflected in the auditory brainstem, our findings have implications not only for current models of amusia but also for auditory functioning in general. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  11. Dyslexia risk gene relates to representation of sound in the auditory brainstem.

    Science.gov (United States)

    Neef, Nicole E; Müller, Bent; Liebig, Johanna; Schaadt, Gesa; Grigutsch, Maren; Gunter, Thomas C; Wilcke, Arndt; Kirsten, Holger; Skeide, Michael A; Kraft, Indra; Kraus, Nina; Emmrich, Frank; Brauer, Jens; Boltze, Johannes; Friederici, Angela D

    2017-04-01

    Dyslexia is a reading disorder with strong associations with KIAA0319 and DCDC2. Both genes play a functional role in spike time precision of neurons. Strikingly, poor readers show an imprecise encoding of fast transients of speech in the auditory brainstem. Whether dyslexia risk genes are related to the quality of sound encoding in the auditory brainstem remains to be investigated. Here, we quantified the response consistency of speech-evoked brainstem responses to the acoustically presented syllable [da] in 159 genotyped, literate and preliterate children. When controlling for age, sex, familial risk and intelligence, partial correlation analyses associated a higher dyslexia risk loading with KIAA0319 with noisier responses. In contrast, a higher risk loading with DCDC2 was associated with a trend towards more stable responses. These results suggest that unstable representation of sound, and thus, reduced neural discrimination ability of stop consonants, occurred in genotypes carrying a higher amount of KIAA0319 risk alleles. Current data provide the first evidence that the dyslexia-associated gene KIAA0319 can alter brainstem responses and impair phoneme processing in the auditory brainstem. This brain-gene relationship provides insight into the complex relationships between phenotype and genotype thereby improving the understanding of the dyslexia-inherent complex multifactorial condition. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Neonatal neurological disorders involving the brainstem: neurosonographic approaches through the squamous suture and the foramen magnum

    Energy Technology Data Exchange (ETDEWEB)

    Tu, Yi-Fang [National Cheng Kung University Hospital, Department of Emergency Medicine, Tainan (Taiwan); Chen, Cheng-Yu [National Defense Medical Center, Department of Radiology, Taipei (Taiwan); Lin, Yuh-Jey [National Cheng Kung University Hospital, Department of Pediatrics, Tainan (Taiwan); Chang, Ying-Chao [Kaohsiung Chang Gung Children Hospital, Department of Pediatrics, Kaohsiung (Taiwan); Huang, Chao-Ching [National Cheng Kung University Hospital, Department of Pediatrics, Tainan (Taiwan); National Cheng Kung University Hospital, Department of Institute of Molecular Medicine, Tainan (Taiwan)

    2005-09-01

    Brainstem damage which often indicates a critical condition is usually underestimated by trans-anterior-fontanel neurosonography (NS) owing to the far-field limitations. Instead, NS alternately scanning through the squamous suture of the temporal bones and the foramen magnum could provide a better visualization of the brainstem structures. The NS characteristics of brainstem lesions caused by various neonatal neurological disorders, such as hypoxic-ischemic encephalopathy (HIE), metabolic encephalopathy, birth trauma and bacterial meningoencephalitis, can be depicted at the acute stage. An echogenic change in the midbrain was found in patients with HIE or metabolic encephalopathy. In addition to the echogenic change, bilateral transtentorial temporal lobe herniation distorting the contour of the midbrain was observed in a patient with group B streptococcus meningoencephalitis, whereas echogenic changes at the level of the pons and/or the medulla oblongata, mainly localized in the dorsal part, could be observed in newborns with severe HIE, maple syrup urine disease or birth trauma. In this pictorial assay, we demonstrate the feasibility of NS imaging in evaluating the entire brainstem structure of critically ill neonates in the near field and illustrate the characteristic features of brainstem involvement in various neonatal neurological disorders along with computed tomography or magnetic resonance imaging correlation. (orig.)

  13. Evidence for altered basal ganglia-brainstem connections in cervical dystonia.

    Directory of Open Access Journals (Sweden)

    Anne J Blood

    Full Text Available There has been increasing interest in the interaction of the basal ganglia with the cerebellum and the brainstem in motor control and movement disorders. In addition, it has been suggested that these subcortical connections with the basal ganglia may help to coordinate a network of regions involved in mediating posture and stabilization. While studies in animal models support a role for this circuitry in the pathophysiology of the movement disorder dystonia, thus far, there is only indirect evidence for this in humans with dystonia.In the current study we investigated probabilistic diffusion tractography in DYT1-negative patients with cervical dystonia and matched healthy control subjects, with the goal of showing that patients exhibit altered microstructure in the connectivity between the pallidum and brainstem. The brainstem regions investigated included nuclei that are known to exhibit strong connections with the cerebellum. We observed large clusters of tractography differences in patients relative to healthy controls, between the pallidum and the brainstem. Tractography was decreased in the left hemisphere and increased in the right hemisphere in patients, suggesting a potential basis for the left/right white matter asymmetry we previously observed in focal dystonia patients.These findings support the hypothesis that connections between the basal ganglia and brainstem play a role in the pathophysiology of dystonia.

  14. Optimal technique of linear accelerator-based stereotactic radiosurgery for tumors adjacent to brainstem.

    Science.gov (United States)

    Chang, Chiou-Shiung; Hwang, Jing-Min; Tai, Po-An; Chang, You-Kang; Wang, Yu-Nong; Shih, Rompin; Chuang, Keh-Shih

    2016-01-01

    Stereotactic radiosurgery (SRS) is a well-established technique that is replacing whole-brain irradiation in the treatment of intracranial lesions, which leads to better preservation of brain functions, and therefore a better quality of life for the patient. There are several available forms of linear accelerator (LINAC)-based SRS, and the goal of the present study is to identify which of these techniques is best (as evaluated by dosimetric outcomes statistically) when the target is located adjacent to brainstem. We collected the records of 17 patients with lesions close to the brainstem who had previously been treated with single-fraction radiosurgery. In all, 5 different lesion catalogs were collected, and the patients were divided into 2 distance groups-1 consisting of 7 patients with a target-to-brainstem distance of less than 0.5cm, and the other of 10 patients with a target-to-brainstem distance of ≥ 0.5 and linear accelerator is only 1 modality can to establish for SRS treatment. Based on statistical evidence retrospectively, we recommend VMAT as the optimal technique for delivering treatment to tumors adjacent to brainstem. Copyright © 2016 American Association of Medical Dosimetrists. All rights reserved.

  15. Stacking denoising auto-encoders in a deep network to segment the brainstem on MRI in brain cancer patients: A clinical study.

    Science.gov (United States)

    Dolz, Jose; Betrouni, Nacim; Quidet, Mathilde; Kharroubi, Dris; Leroy, Henri A; Reyns, Nicolas; Massoptier, Laurent; Vermandel, Maximilien

    2016-09-01

    Delineation of organs at risk (OARs) is a crucial step in surgical and treatment planning in brain cancer, where precise OARs volume delineation is required. However, this task is still often manually performed, which is time-consuming and prone to observer variability. To tackle these issues a deep learning approach based on stacking denoising auto-encoders has been proposed to segment the brainstem on magnetic resonance images in brain cancer context. Additionally to classical features used in machine learning to segment brain structures, two new features are suggested. Four experts participated in this study by segmenting the brainstem on 9 patients who underwent radiosurgery. Analysis of variance on shape and volume similarity metrics indicated that there were significant differences (p<0.05) between the groups of manual annotations and automatic segmentations. Experimental evaluation also showed an overlapping higher than 90% with respect to the ground truth. These results are comparable, and often higher, to those of the state of the art segmentation methods but with a considerably reduction of the segmentation time. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Antibacterial effect of taurolidine (2%) on established dental plaque biofilm.

    Science.gov (United States)

    Arweiler, Nicole Birgit; Auschill, Thorsten Mathias; Sculean, Anton

    2012-04-01

    Preliminary data have suggested that taurolidine may bear promising disinfectant properties for the therapy of bacterial infections. However, at present, the potential antibacterial effect of taurolidine on the supragingival plaque biofilm is unknown. To evaluate the antibacterial effect of taurolidine on the supragingival plaque biofilm using the vital fluorescence technique and to compare it with the effect of NaCl and chlorhexidine (CHX), 18 subjects had to refrain from all mechanical and chemical hygiene measures for 24 h. A voluminous supragingival plaque sample was taken from the buccal surfaces of the lower molars and wiped on an objective slide. The sample was then divided into three equal parts and mounted with one of the three test or control preparations (a) NaCl, (b) taurolidine 2% and (c) CHX 0.2%. After a reaction time of 2 min, the test solutions were sucked of. Subsequently, the plaque biofilm was stained with fluorescence dye and vitality of the plaque flora was evaluated under the fluorescence microscope (VF%). Plaque samples treated with NaCl showed a mean VF of 82.42 ± 6.04%. Taurolidine affected mean VF with 47.57 ± 16.60% significantly (p plaque biofilm which was, however, not as pronounced as that of CHX.

  17. Intravascular photoacoustic imaging: a new tool for vulnerable plaque identification.

    Science.gov (United States)

    Jansen, Krista; van Soest, Gijs; van der Steen, Antonius F W

    2014-06-01

    The vulnerable atherosclerotic plaque is believed to be at the root of the majority of acute coronary events. Even though the exact origins of plaque vulnerability remain elusive, the thin-cap fibroatheroma, characterized by a lipid-rich necrotic core covered by a thin fibrous cap, is considered to be the most prominent type of vulnerable plaque. No clinically available imaging technique can characterize atherosclerotic lesions to the extent needed to determine plaque vulnerability prognostically. Intravascular photoacoustic imaging (IVPA) has the potential to take a significant step in that direction by imaging both plaque structure and composition. IVPA is a natural extension of intravascular ultrasound that adds tissue type specificity to the images. IVPA utilizes the optical contrast provided by the differences in the absorption spectra of plaque components to image composition. Its capability to image lipids in human coronary atherosclerosis has been shown extensively ex vivo and has recently been translated to an in vivo animal model. Other disease markers that have been successfully targeted are calcium and inflammatory markers, such as macrophages and matrix metalloproteinase; the latter two through application of exogenous contrast agents. By simultaneously displaying plaque morphology and composition, IVPA can provide a powerful prognostic marker for disease progression, and as such has the potential to transform the current practice in percutaneous coronary intervention. Copyright © 2014 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  18. Collagen and related extracellular matrix proteins in atherosclerotic plaque development.

    Science.gov (United States)

    Shami, Annelie; Gonçalves, Isabel; Hultgårdh-Nilsson, Anna

    2014-10-01

    The structure, composition and turnover of the extracellular matrix (ECM) as well as cell-matrix interactions are crucial in the developing atherosclerotic plaque. There is a need for further insight into specific proteins in the ECM and their functions in the developing plaque, and during the last few years a number of publications have highlighted this very important field of research. These novel findings will be addressed in the present review. This review covers literature focused on collagen and ECM proteins interacting with collagen, and what their roles may be in plaque development. Acute myocardial infarction and stroke are common diseases that cause disability and mortality, and the underlying mechanism is often the rupture of a vulnerable atherosclerotic plaque. The vascular ECM and the tissue repair in the atherosclerotic lesion are important players in plaque progression. Understanding how specific proteins in the ECM interact with cells in the plaque and affect the fate of the plaque can lead to new treatments for cardiovascular disease.

  19. Bone marrow endothelial progenitors in atherosclerotic plaque resolution

    Science.gov (United States)

    Yao, Longbiao; Heuser-Baker, Janet; Herlea-Pana, Oana; Barlic-Dicen, Jana

    2013-01-01

    Atherosclerosis is a major cause of morbidity and mortality in the United States. Persistently elevated circulating low-density lipoprotein, or hypercholesterolemia, and deposition of low-density lipoprotein in the vascular wall are the main inducers of atherosclerosis, which manifests itself as arterial lesions or plaques. Some plaques become thrombosis-prone and rupture, causing acute myocardial infarction or stroke. Lowering plasma cholesterol through the use of statins is the primary intervention against atherosclerosis. Treatment with statins slows progression of atherosclerosis but can only support limited plaque regression. Partially regressed plaques continue to pose a serious threat due to their remaining potential to rupture. Thus, new interventions inducing complete reversal of atherosclerosis are being sought. Implementation of new therapies will require clear understanding of the mechanisms driving plaque resolution. In this Commentary, we highlight the role of bone marrow endothelial progenitors in atherosclerotic plaque regression and discuss how regenerative cell-based interventions could be used in combination with plasma lipid-lowering to induce plaque reversal in order to prevent and/or reduce adverse cardiovascular events. PMID:23538778

  20. Atherosclerotic Plaque Destabilization in Mice: A Comparative Study.

    Directory of Open Access Journals (Sweden)

    Helene Hartwig

    Full Text Available Atherosclerosis-associated diseases are the main cause of mortality and morbidity in western societies. The progression of atherosclerosis is a dynamic process evolving from early to advanced lesions that may become rupture-prone vulnerable plaques. Acute coronary syndromes are the clinical manifestation of life-threatening thrombotic events associated with high-risk vulnerable plaques. Hyperlipidemic mouse models have been extensively used in studying the mechanisms controlling initiation and progression of atherosclerosis. However, the understanding of mechanisms leading to atherosclerotic plaque destabilization has been hampered by the lack of proper animal models mimicking this process. Although various mouse models generate atherosclerotic plaques with histological features of human advanced lesions, a consensus model to study atherosclerotic plaque destabilization is still lacking. Hence, we studied the degree and features of plaque vulnerability in different mouse models of atherosclerotic plaque destabilization and find that the model based on the placement of a shear stress modifier in combination with hypercholesterolemia represent with high incidence the most human like lesions compared to the other models.

  1. Plaque Characteristics of Patients with Symptomatic Mild Carotid Artery Stenosis.

    Science.gov (United States)

    Takai, Hiroki; Uemura, Juniti; Yagita, Yoshiki; Ogawa, Yukari; Kinoshita, Keita; Hirai, Satoshi; Ishihara, Manabu; Hara, Keijirou; Toi, Hiroyuki; Matsubara, Shunji; Nishimura, Hirotake; Uno, Masaaki

    2018-03-20

    Carotid revascularization may be considered for severe stenosis, but its use for symptomatic mild stenosis (<50%) with vulnerable plaque or ulcer remains uncertain. The characteristics of patients with symptomatic mild stenosis who underwent revascularization are reviewed. The subjects of this study were 18 patients with symptomatic mild stenosis (<50%) on angiography from among 175 patients who underwent revascularization in our department. The plaques were evaluated by black-blood magnetic resonance imaging (BB-MRI) and ultrasonography (US) and classified into 2 types: type 1 (n = 15), a lesion with an ulcer or mobile plaque or thrombosis on angiography or US; and type 2 (n = 3), a lesion without any of the above. Fourteen patients underwent carotid endarterectomy (CEA), and 4 patients underwent carotid artery stenting. The stenosis on angiography was 27.2% ± 10.7 (5%-41%), and the area carotid artery stenosis rate on US was 69.8 ± 14.5% (44.5%-97%). The stenosis rate of these 2 methods was not at all correlated. In type 1 plaque that underwent CEA, 10 of 11 patients had vulnerable plaque by histopathology, and 1 patient had thrombus on the plaque by operative findings. In type 2 plaque that underwent CEA, all patients had vulnerable plaque by histopathology. During the follow-up period, none of the patients had restenosis or stroke. The findings of US and BB-MRI in patients with symptomatic mild stenosis (<50%) on angiography are important for determining treatment. If BB-MRI or US shows the findings of vulnerable plaque in mild stenosis, surgical treatment may be considered for these patients. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  2. Plaque Index in Multi-Bracket Fixed Appliances

    International Nuclear Information System (INIS)

    Rahim, Z.H.; Shaikh, S.; Razak, F.A.

    2014-01-01

    To compare the plaque index in patients receiving multi-bracket fixed orthodontic treatment for various factors like age, gender, socio-economic status, brushing practices, meal habits, types of brackets, types of ligations, use of mouthwash and duration of treatment. Study Design: Cross-sectional analytical study. Place and Duration of Study: Orthodontics Clinic, The Aga Khan University Hospital, from September to November 2011. Methodology: Socio-demographic and clinical modalities were defined and recorded for 131 patients having multi-bracket fixed appliances. The plaque index of subjects were recorded according to the Silness and Loe plaque index method. Independent sample t-test was used to see difference in plaque index in factors having two variables. One way ANOVA and Post-Hoc Tukey tests were used to see difference in plaque index in factors having three variables. Kappa statistics was used to assess inter examiner reliability. P-value 0.05 was taken to be significant. Results: The sample comprised of 37% males (n = 48) and 63% females (n = 83). The plaque index had statistically significant association with practice of brushing i.e., timing of brushing (p=0.001), method of brushing (p=0.08), type of ligatures (p=0.05) and frequency of visits (p=0.01). Conclusion: The plaque accumulation is significantly decreased in subjects who brush the teeth twice or more than twice a day and those who brush their teeth after breakfast. The use of interdental brush and stainless steel ligatures had significantly low plaque. Subjects presenting with more frequent appointments of short-period had significantly less plaque. (author)

  3. Hydrogen sulfide production from subgingival plaque samples.

    Science.gov (United States)

    Basic, A; Dahlén, G

    2015-10-01

    Periodontitis is a polymicrobial anaerobe infection. Little is known about the dysbiotic microbiota and the role of bacterial metabolites in the disease process. It is suggested that the production of certain waste products in the proteolytic metabolism may work as markers for disease severity. Hydrogen sulfide (H2S) is a gas produced by degradation of proteins in the subgingival pocket. It is highly toxic and believed to have pro-inflammatory properties. We aimed to study H2S production from subgingival plaque samples in relation to disease severity in subjects with natural development of the disease, using a colorimetric method based on bismuth precipitation. In remote areas of northern Thailand, adults with poor oral hygiene habits and a natural development of periodontal disease were examined for their oral health status. H2S production was measured with the bismuth method and subgingival plaque samples were analyzed for the presence of 20 bacterial species with the checkerboard DNA-DNA hybridization technique. In total, 43 subjects were examined (age 40-60 years, mean PI 95 ± 6.6%). Fifty-six percent had moderate periodontal breakdown (CAL > 3  7 mm) on at least one site. Parvimonas micra, Filifactor alocis, Porphyromonas endodontalis and Fusobacterium nucleatum were frequently detected. H2S production could not be correlated to periodontal disease severity (PPD or CAL at sampled sites) or to a specific bacterial composition. Site 21 had statistically lower production of H2S (p = 0.02) compared to 16 and 46. Betel nut chewers had statistically significant lower H2S production (p = 0.01) than non-chewers. Rapid detection and estimation of subgingival H2S production capacity was easily and reliably tested by the colorimetric bismuth sulfide precipitation method. H2S may be a valuable clinical marker for degradation of proteins in the subgingival pocket. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Increased brainstem perfusion, but no blood-brain barrier disruption, during attacks of migraine with aura

    DEFF Research Database (Denmark)

    Hougaard, Anders; Amin, Faisal M; Christensen, Casper E

    2017-01-01

    symptoms are related to the headache phase of migraine. Animal studies suggest that cortical spreading depression, the likely mechanism of migraine aura, causes disruption of the blood-brain barrier and noxious stimulation of trigeminal afferents leading to activation of brainstem nuclei and triggering...... of migraine headache. We used the sensitive and validated technique of dynamic contrast-enhanced high-field magnetic resonance imaging to simultaneously investigate blood-brain barrier permeability and tissue perfusion in the brainstem (at the level of the lower pons), visual cortex, and brain areas......-free day. The mean time from attack onset to scanning was 7.6 h. We found increased brainstem perfusion bilaterally during migraine with aura attacks. Perfusion also increased in the visual cortex and posterior white matter following migraine aura. We found no increase in blood-brain barrier permeability...

  5. Cerebral and brainstem electrophysiologic activity during euthanasia with pentobarbital sodium in horses.

    Science.gov (United States)

    Aleman, M; Williams, D C; Guedes, A; Madigan, J E

    2015-01-01

    An overdose of pentobarbital sodium administered i.v. is the most commonly used method of euthanasia in veterinary medicine. Determining death after the infusion relies on the observation of physical variables. However, it is unknown when cortical electrical activity and brainstem function are lost in a sequence of events before death. To examine changes in the electrical activity of the cerebral cortex and brainstem during an overdose of pentobarbital sodium solution for euthanasia. Our testing hypothesis is that isoelectric pattern of the brain in support of brain death occurs before absence of electrocardiogram (ECG) activity. Fifteen horses requiring euthanasia. Prospective observational study. Horses with neurologic, orthopedic, and cardiac illnesses were selected and instrumented for recording of electroencephalogram, electrooculogram, brainstem auditory evoked response (BAER), and ECG. Physical and neurologic (brainstem reflexes) variables were monitored. Loss of cortical electrical activity occurred during or within 52 seconds after the infusion of euthanasia solution. Cessation of brainstem function as evidenced by a lack of brainstem reflexes and disappearance of the BAER happened subsequently. Despite undetectable heart sounds, palpable arterial pulse, and mean arterial pressure, recordable ECG was the last variable to be lost after the infusion (5.5-16 minutes after end of the infusion). Overdose of pentobarbital sodium solution administered i.v. is an effective, fast, and humane method of euthanasia. Brain death occurs within 73-261 seconds of the infusion. Although absence of ECG activity takes longer to occur, brain death has already occurred. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  6. Right-sided dominance of the bilateral vestibular system in the upper brainstem and thalamus.

    Science.gov (United States)

    Dieterich, Marianne; Kirsch, V; Brandt, T

    2017-10-01

    MRI diffusion tensor imaging tractography was performed on the bilateral vestibular brainstem pathways, which run from the vestibular nuclei via the paramedian and posterolateral thalamic subnuclei to the parieto-insular vestibular cortex. Twenty-one right-handed healthy subjects participated. Quantitative analysis revealed a rope-ladder-like system of vestibular pathways in the brainstem with crossings at pontine and mesencephalic levels. Three structural types of right-left fiber distributions could be delineated: (1) evenly distributed pathways at the lower pontine level from the vestibular nuclei to the pontine crossing, (2) a moderate, pontomesencephalic right-sided lateralization between the pontine and mesencephalic crossings, and (3) a further increase of the right-sided lateralization above the mesencephalic crossing leading to the thalamic vestibular subnuclei. The increasing lateralization along the brainstem was the result of an asymmetric number of pontine and mesencephalic crossing fibers which was higher for left-to-right crossings. The dominance of the right vestibular meso-diencephalic circuitry in right-handers corresponds to the right-hemispheric dominance of the vestibular cortical network. The structural asymmetry apparent in the upper brainstem might be interpreted in relation to the different functions of the vestibular system depending on their anatomical level: a symmetrical sensorimotor reflex control of eye, head, and body mediated by the lower brainstem; a lateralized right-sided upper brainstem-thalamic function as part of the dominant right-sided cortical/subcortical vestibular system that enables a global percept of body motion and orientation in space.

  7. Interictal dysfunction of a brainstem descending modulatory center in migraine patients.

    Directory of Open Access Journals (Sweden)

    Eric A Moulton

    Full Text Available The brainstem contains descending circuitry that can modulate nociceptive processing (neural signals associated with pain in the dorsal horn of the spinal cord and the medullary dorsal horn. In migraineurs, abnormal brainstem function during attacks suggest that dysfunction of descending modulation may facilitate migraine attacks, either by reducing descending inhibition or increasing facilitation. To determine whether a brainstem dysfunction could play a role in facilitating migraine attacks, we measured brainstem function in migraineurs when they were not having an attack (i.e. the interictal phase.Using fMRI (functional magnetic resonance imaging, we mapped brainstem activity to heat stimuli in 12 episodic migraine patients during the interictal phase. Separate scans were collected to measure responses to 41 degrees C and noxious heat (pain threshold+1 degrees C. Stimuli were either applied to the forehead on the affected side (as reported during an attack or the dorsum of the hand. This was repeated in 12 age-gender-matched control subjects, and the side tested corresponded to that in the matched migraine patients. Nucleus cuneiformis (NCF, a component of brainstem pain modulatory circuits, appears to be hypofunctional in migraineurs. 3 out of the 4 thermal stimulus conditions showed significantly greater NCF activation in control subjects than the migraine patients.Altered descending modulation has been postulated to contribute to migraine, leading to loss of inhibition or enhanced facilitation resulting in hyperexcitability of trigeminovascular neurons. NCF function could potentially serve as a diagnostic measure in migraine patients, even when not experiencing an attack. This has important implications for the evaluation of therapies for migraine.

  8. 3D Isotropic MR Culprit Plaque Visualization of Carotid Plaque Edema and Hemorrhage with Motion Sensitized Blood Suppression

    DEFF Research Database (Denmark)

    Søvsø Szocska Hansen, Esben; Pedersen, Steen Fjord; Bloch, Lars Ø.

    2014-01-01

    hemorrhage and plaque edema may represent advanced stages of atherosclerosis[1, 2]. In this study, we present a novel multi-contrast 3D motion sensitized black-blood CMR imaging sequence, which detects both plaque edema and hemorrhage with positive contrast. Subjects and Methods The 3D imaging sequence...... to lumen was 39.74±6.75. Discussion/Conclusion In conclusion, the proposed 3D isotropic multi-contrast CMR technique detects plaque edema and hemorrhage with positive contrast and excellent black-blood contrast, which may facilitate evaluation of carotid atherosclerosis. Ongoing studies will include CMR...

  9. [Forensic application of brainstem auditory evoked potential in patients with brain concussion].

    Science.gov (United States)

    Zheng, Xing-Bin; Li, Sheng-Yan; Huang, Si-Xing; Ma, Ke-Xin

    2008-12-01

    To investigate changes of brainstem auditory evoked potential (BAEP) in patients with brain concussion. Nineteen patients with brain concussion were studied with BAEP examination. The data was compared to the healthy persons reported in literatures. The abnormal rate of BAEP for patients with brain concussion was 89.5%. There was a statistically significant difference between the abnormal rate of patients and that of healthy persons (Pconcussion was 73.7%, indicating dysfunction of the brainstem in those patients. BAEP might be helpful in forensic diagnosis of brain concussion.

  10. Argonne National Laboratory research offers clues to Alzheimer's plaques

    CERN Multimedia

    2003-01-01

    Researchers from Argonne National Laboratory and the University of Chicago have developed methods to directly observe the structure and growth of microscopic filaments that form the characteristic plaques found in the brains of those with Alzheimer's Disease (1 page).

  11. Evidence for xylitol 5-P production in human dental plaque

    Energy Technology Data Exchange (ETDEWEB)

    Waaler, S.M. (Department of Preclinical Techniques and Material Sciences and Department of Pedodontics, Dental Faculty, University of Oslo, Oslo (Norway))

    1992-01-01

    The Turku sugar studies indicated that xylitol may possess a caries-therapeutic effect. More recent data show that xylotol exhibits a bacteriostatic activity on a wide range of bacteria based on uptake and expulsion of xylitol. Intracellular xylitol 5-P appears to be a key substance associated with inhibition of bacterial metabolism by xylitol. This has been shown in studies with pure strains of bacteria, mainly Streptococcus mutans. The aim of the present study was to examine if production of xylitol 5-P occurs in freshly collected dental plaque which is exposed to labeled xylitol. Plaque extracts were analyzed by thin-layer chromatography combined with autoradiography and high performance liquid chromatography. Strong indications were obtained that xylitol 5-P is readily produced by dental plaque. No other significant xylitol metabolites were identified. The bacteriostatic properties of xylitol in plaque are a mechanism which may well account for the caries-therapeutic effect of xylitol. (au).

  12. Atherosclerotic Plaque Destabilization Mechanisms, Models, and Therapeutic Strategies

    NARCIS (Netherlands)

    Silvestre-Roig, Carlos; de Winther, Menno P.; Weber, Christian; Daemen, Mat J.; Lutgens, Esther; Soehnlein, Oliver

    2014-01-01

    Understanding the pathophysiology of atherogenesis and the progression of atherosclerosis have been major goals of cardiovascular research during the previous decades. However, the complex molecular and cellular mechanisms underlying plaque destabilization remain largely obscure. Here, we review how

  13. Evidence for xylitol 5-P production in human dental plaque

    International Nuclear Information System (INIS)

    Waaler, S.M.

    1992-01-01

    The Turku sugar studies indicated that xylitol may possess a caries-therapeutic effect. More recent data show that xylotol exhibits a bacteriostatic activity on a wide range of bacteria based on uptake and expulsion of xylitol. Intracellular xylitol 5-P appears to be a key substance associated with inhibition of bacterial metabolism by xylitol. This has been shown in studies with pure strains of bacteria, mainly Streptococcus mutans. The aim of the present study was to examine if production of xylitol 5-P occurs in freshly collected dental plaque which is exposed to labeled xylitol. Plaque extracts were analyzed by thin-layer chromatography combined with autoradiography and high performance liquid chromatography. Strong indications were obtained that xylitol 5-P is readily produced by dental plaque. No other significant xylitol metabolites were identified. The bacteriostatic properties of xylitol in plaque are a mechanism which may well account for the caries-therapeutic effect of xylitol. (au)

  14. Contemporary carotid imaging: from degree of stenosis to plaque vulnerability.

    Science.gov (United States)

    Brinjikji, Waleed; Huston, John; Rabinstein, Alejandro A; Kim, Gyeong-Moon; Lerman, Amir; Lanzino, Giuseppe

    2016-01-01

    Carotid artery stenosis is a well-established risk factor of ischemic stroke, contributing to up to 10%-20% of strokes or transient ischemic attacks. Many clinical trials over the last 20 years have used measurements of carotid artery stenosis as a means to risk stratify patients. However, with improvements in vascular imaging techniques such as CT angiography and MR angiography, ultrasonography, and PET/CT, it is now possible to risk stratify patients, not just on the degree of carotid artery stenosis but also on how vulnerable the plaque is to rupture, resulting in ischemic stroke. These imaging techniques are ushering in an emerging paradigm shift that allows for risk stratifications based on the presence of imaging features such as intraplaque hemorrhage (IPH), plaque ulceration, plaque neovascularity, fibrous cap thickness, and presence of a lipid-rich necrotic core (LRNC). It is important for the neurosurgeon to be aware of these new imaging techniques that allow for improved patient risk stratification and outcomes. For example, a patient with a low-grade stenosis but an ulcerated plaque may benefit more from a revascularization procedure than a patient with a stable 70% asymptomatic stenosis with a thick fibrous cap. This review summarizes the current state-of-the-art advances in carotid plaque imaging. Currently, MRI is the gold standard in carotid plaque imaging, with its high resolution and high sensitivity for identifying IPH, ulceration, LRNC, and inflammation. However, MRI is limited due to time constraints. CT also allows for high-resolution imaging and can accurately detect ulceration and calcification, but cannot reliably differentiate LRNC from IPH. PET/CT is an effective technique to identify active inflammation within the plaque, but it does not allow for assessment of anatomy, ulceration, IPH, or LRNC. Ultrasonography, with the aid of contrast enhancement, is a cost-effective technique to assess plaque morphology and characteristics, but it is

  15. Lectin Pathway of Complement Activation Is Associated with Vulnerability of Atherosclerotic Plaques

    DEFF Research Database (Denmark)

    Fumagalli, Stefano; Perego, Carlo; Zangari, Rosalia

    2017-01-01

    Inflammatory mechanisms may be involved in atherosclerotic plaque rupture. By using a novel histology-based method to quantify plaque instability here, we assess whether lectin pathway (LP) of complement activation, a major inflammation arm, could represent an index of plaque instability. Plaques...

  16. MR chemical shift imaging and spectroscopy of atherosclerotic plaque

    International Nuclear Information System (INIS)

    Vinitski, S.; Consigny, P.M.; Shapiro, M.J.; Janes, N.; Smullens, S.N.; Rifkin, M.D.

    1989-01-01

    The purpose of this study was to develop a technique for in vivo imaging and characterization of atherosclerotic plaque. The authors used a spin-echo technique with a short echo time (TE) of 11 msec. Lipid/water suppression was achieved by means of hybrid chemical shift imaging. Lesions were induced in three rabbits by a combination of balloon denudation of the abdominal aorta and a high-cholesterol diet. Following in vivo imaging of these rabbit aortas and human carotid arteries (1.5 T), the animals were killed or carotid endarterectomy was performed so that the plaques could be excised. The plaques were then analyzed in vitro both histologically and with high-resolution spectroscopy (8.5 T). Use of the short TE improved lesion visualization. The fat/water suppression showed only a small amount of mobile lipids in plaque. Both MR spectroscopic and histologic analysis corroborated these images. The composition of atherosclerotic plaques in both humans and rabbits was demonstrated to be heterogeneous, with predominantly nonmobile lipids. These results suggest that the combination of short TE MR imaging and fat/water suppression can identify plaque and delineate areas containing mobile lipids

  17. The absence of later wave components in auditory brainstem responses as an initial manifestation of type 2 Gaucher disease.

    Science.gov (United States)

    Okubo, Yusuke; Goto, Masahiro; Sakakibara, Hiroshi; Terakawa, Toshiro; Kaneko, Takashi; Miyama, Sahoko

    2014-12-01

    Type 2 Gaucher disease is the most severe neuronopathic form of Gaucher disease and is characterized by severe neurodegeneration with brainstem involvement and organ failure. Prediction or diagnosis of type 2 Gaucher disease before the development of neurological complications is difficult. A 5-month-old female infant presented with deafness without other neurological abnormalities. Auditory brainstem response analysis revealed the absence of later wave components. Two months later, muscular rigidity became evident, followed by the development of opisthotonus and strabismus. Rapid progression of splenomegaly led to the diagnosis of type 2 Gaucher disease. Abnormal auditory brainstem response findings may already exist before the development of severe brainstem abnormalities such as muscular rigidity and opisthotonus in type 2 Gaucher disease. When patients present with deafness and absent later wave components on auditory brainstem response, type 2 Gaucher disease should be included in the differential diagnosis even in the absence of other neurological abnormalities. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Population calcium imaging of spontaneous respiratory and novel motor activity in the facial nucleus and ventral brainstem in newborn mice

    DEFF Research Database (Denmark)

    Persson, Karin; Rekling, Jens C

    2011-01-01

    The brainstem contains rhythm and pattern forming circuits, which drive cranial and spinal motor pools to produce respiratory and other motor patterns. Here we used calcium imaging combined with nerve recordings in newborn mice to reveal spontaneous population activity in the ventral brainstem...... and in the facial nucleus. In Fluo-8AM loaded brainstem-spinal cord preparations, respiratory activity on cervical nerves was synchronized with calcium signals at the ventrolateral brainstem surface. Individual ventrolateral neurons at the level of the parafacial respiratory group showed perfect or partial...... synchrony with respiratory nerve bursts. In brainstem-spinal cord preparations, cut at the level of the mid-facial nucleus, calcium signals were recorded in the dorsal, lateral and medial facial subnuclei during respiratory activity. Strong activity initiated in the dorsal subnucleus, followed by activity...

  19. The effect of pH, temperature and plaque thickness on the hydrolysis of monofluorophosphate in experimental dental plaque.

    Science.gov (United States)

    Pearce, E I F; Dibdin, G H

    2003-01-01

    Monofluorophosphate (MFP), an anti-caries agent commonly used in toothpaste, is known to be degraded to fluoride and orthophosphate by bacterial phosphatases in dental plaque. We have examined the effect of pH, temperature, plaque thickness and some ions on this process. Both natural plaque and artificial microcosm plaque incubated with purified MFP at pH 4-10 showed an optimum pH of approximately 8 for hydrolysis. Diffusion and concomitant hydrolysis were examined in an apparatus in which artificial plaque was held between rigid membranes separating two chambers. When MFP diffused through a plaque of 0.51-mm thickness over 4 h it was almost completely hydrolysed at pH 8, but hydrolysis on diffusion decreased as the pH deviated from 8. MFP in toothpaste extract showed a similar pH susceptibility to hydrolysis, according to the inherent pH of the toothpaste. Hydrolysis of MFP in the toothpaste was reduced by no more than 10% when compared with a matched-pH control, suggesting that other toothpaste ingredients had no major influence on hydrolysis. Transport was slower and hydrolysis at pH 6 more complete the thicker the plaque, but hydrolysis was not significantly slower at 23 degrees C than at 37 degrees C. The addition of various potential activating or inhibiting ions at 0.1 and 1.0 mmol/l had small and non-significant effects on hydrolysis. The results suggest that MFP toothpaste should be formulated and used to maximise enzymic hydrolysis of this complex anion, and that plaque pH control is probably the most important factor. Copyright 2003 S. Karger AG, Basel

  20. Factors Influencing Virulence and Plaque Properties of Attenuated Venezuelan Equine Encephalomyelitis Virus Populations

    Science.gov (United States)

    Hearn, Henry J.; Seliokas, Zenonas V.; Andersen, Arthur A.

    1969-01-01

    A minority of stable large-plaque virus increased proportionally in stored unstable attenuated (9t) Venezuelan equine encephalomyelitis virus populations. L-cell-grown progeny (9t2) of stored 9t showed large amounts of large-plaque virus and increased virulence. Small-plaque virus inhibited large-plaque virus but not the reverse. Serial passage of small-plaque virus from 9t2 yielded a strain (20t) that was more attenuated than 9t. PMID:5823235

  1. Brainstem response audiometry in the determination of low-frequency hearing loss : a study of various methods for frequency-specific ABR-threshold assessment

    NARCIS (Netherlands)

    E.A.G.J. Conijn

    1992-01-01

    textabstractBrainstem Electric Response Audiometry (BERA) is a method to visualize some of the electric activity generated in the auditory nerve and the brainstem during the processing of sound. The amplitude of the Auditory Brainstem Response (ABR) is very small (0.05-0.5 flV). The potentials

  2. Developmental study of vitamin C distribution in children's brainstems by immunohistochemistry.

    Science.gov (United States)

    Coveñas, R; González-Fuentes, J; Rivas-Infante, E; Lagartos-Donate, M J; Mangas, A; Geffard, M; Arroyo-Jiménez, M M; Cebada-Sánchez, S; Insausti, R; Marcos, P

    2015-09-01

    Vitamin C (Vit C) is an important antioxidant, exerts powerful neuroprotective brain effects and plays a role in neuronal development and maturation. Vit C is present in brain tissue at higher concentrations than in other organs, but its detailed distribution in brain is unknown. Immunohistochemical detection of this vitamin has been performed by using a highly specific antibody against Vit C. The aim of the present work was to analyze the distribution of Vit C in children's brainstems during postnatal development, comparing two groups of ages: younger and older than one year of life. In general, the same areas showing neurons with Vit C in young cases are also immunostained at older ages. The distribution of neurons containing Vit C was broader in the brainstems of older children, suggesting that brainstem neurons maintain or even increase their ability to retain Vit C along the life span. Immunohistochemical labeling revealed only cell bodies containing this vitamin, and no immunoreactive fibers were observed. The distribution pattern of Vit C in children's brainstems suggests a possible role of Vit C in brain homeostatic regulation. In addition, the constant presence of Vit C in neurons of locus coeruleus supports the important role of Vit C in noradrenaline synthesis, which seemed to be maintained along postnatal development. Copyright © 2015 Elsevier GmbH. All rights reserved.

  3. Stereotactic radiosurgery for deep intracranial arteriovenous malformations, part 1: Brainstem arteriovenous malformations.

    Science.gov (United States)

    Cohen-Inbar, Or; Ding, Dale; Chen, Ching-Jen; Sheehan, Jason P

    2016-02-01

    The management of brainstem arteriovenous malformations (AVM) are one of the greatest challenges encountered by neurosurgeons. Brainstem AVM have a higher risk of hemorrhage compared to AVM in other locations, and rupture of these lesions commonly results in devastating neurological morbidity and mortality. The potential morbidity associated with currently available treatment modalities further compounds the complexity of decision making for affected patients. Stereotactic radiosurgery (SRS) has an important role in the management of brainstem AVM. SRS offers acceptable obliteration rates with lower risks of hemorrhage occurring during the latency period. Complex nidal architecture requires a multi-disciplinary treatment approach. Nidi partly involving subpial/epipial regions of the dorsal midbrain or cerebellopontine angle should be considered for a combination of endovascular embolization, micro-surgical resection and SRS. Considering the fact that incompletely obliterated lesions (even when reduced in size) could still cause lethal hemorrhages, additional treatment, including repeat SRS and surgical resection should be considered when complete obliteration is not achieved by first SRS. Patients with brainstem AVM require continued clinical and radiological observation and follow-up after SRS, well after angiographic obliteration has been confirmed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Two oculomotor-related areas of the brainstem project to the dorsolateral periaqueductal gray.

    NARCIS (Netherlands)

    Klop, E.M.; Mouton, Leonora J.; Holstege, Gert

    2005-01-01

    The dorsolateral column of the periaqueductal gray (PAGdl) is usually associated with defensive behavior, but how this is brought about is not yet fully understood. In order to elucidate the function of PAGdl, its afferents from the brainstem were investigated in cats. Retrograde tracing results

  5. Normal development of brainstem in childhood. Measurement of the area on mid-sagittal MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Kutomi, Kimiko [Teikyo Univ., Tokyo (Japan). Faculty of Medicine

    2005-05-01

    Developmental abnormality of brainstem is shown in pediatric patients with mental retardation, autism, periventricular leukomalacia, neurodegenerative disease, and so on. Our purpose here is to clarify the normal developmental pattern of the brainstem. We measured the area of tectum, midbrain tegmentum, pons, basis pontis and pontine tegmentum on mid-sagittal MR images in 111 children (newborn to 20 year old). Different growth patterns were shown in all parts of the brainstem. Tectum showed a subtle increase in area from the newborn to adult period, while midbrain tegmentum and pontine tegmenturn showed a mild and gradual increase in area. Pons and pontine tegmentum showed a rapid and prominent increase in area from newborn to infant period and gradual increase in area until the adult period. These different growth patterns seemed to be consistent with differences in the myelination cycles of the neuronal fibers, maturation of the nuclei and proliferation of glial cells in each part of the brainstem. Mid-sagittal MR imaging of the head is accurate and reproducible and is used conveniently in routine head MR study, making it very useful for the diagnosis of many central nervous diseases and anomalies. We believe that this new milestone provided in this study will be helpful in distinguishing normal children from those that have neurodegenerative disorders. (author)

  6. Normal development of brainstem in childhood. Measurement of the area on mid-sagittal MR imaging

    International Nuclear Information System (INIS)

    Kutomi, Kimiko

    2005-01-01

    Developmental abnormality of brainstem is shown in pediatric patients with mental retardation, autism, periventricular leukomalacia, neurodegenerative disease, and so on. Our purpose here is to clarify the normal developmental pattern of the brainstem. We measured the area of tectum, midbrain tegmentum, pons, basis pontis and pontine tegmentum on mid-sagittal MR images in 111 children (newborn to 20 year old). Different growth patterns were shown in all parts of the brainstem. Tectum showed a subtle increase in area from the newborn to adult period, while midbrain tegmentum and pontine tegmenturn showed a mild and gradual increase in area. Pons and pontine tegmentum showed a rapid and prominent increase in area from newborn to infant period and gradual increase in area until the adult period. These different growth patterns seemed to be consistent with differences in the myelination cycles of the neuronal fibers, maturation of the nuclei and proliferation of glial cells in each part of the brainstem. Mid-sagittal MR imaging of the head is accurate and reproducible and is used conveniently in routine head MR study, making it very useful for the diagnosis of many central nervous diseases and anomalies. We believe that this new milestone provided in this study will be helpful in distinguishing normal children from those that have neurodegenerative disorders. (author)

  7. Investigation of auditory brainstem function in elderly diabetic patients with presbycusis.

    Science.gov (United States)

    Kovacií, Jelena; Lajtman, Zoran; Ozegović, Ivan; Knezević, Predrag; Carić, Tomislav; Vlasić, Ana

    2009-01-01

    We performed brainstem auditory evoked potential (BAEP) examinations in 100 patients older than 60 years and having type I diabetes mellitus and presbycusis. The aim of our investigation was to compare the BAEP results of this group with those of healthy controls with presbycusis and to look for possible correlations between alteration of the auditory brainstem function and the aging of elderly diabetic patients. Absolute and interpeak latencies of all waves were prolonged significantly in the study group of diabetic patients. The amplitudes of all waves I through V were diminished in the study group as compared to those in the control group, with statistical significance present for all waves. Analysis of the latencies (waves I, II, I, and V), interpeak latencies (I-V), and amplitudes (I, II, III, and V) of BAEP revealed a significant difference between those of diabetics and those of healthy elderly controls with presbycusis. These data support a hypothesis that there is a brainstem neuropathy in diabetes mellitus that can be assessed with auditory brainstem response testing even in the group of elderly patients with sensorineural hearing loss.

  8. Effects of brainstem lesions on the masseter inhibitory reflex. Functional mechanisms of reflex pathways

    NARCIS (Netherlands)

    Ongerboer de Visser, B. W.; Cruccu, G.; Manfredi, M.; Koelman, J. H.

    1990-01-01

    The masseter inhibitory reflex (MIR) was investigated in 16 patients with localized brainstem lesions involving the trigeminal system. The MIR consists of two phases of EMG silence (S1 and S2) evoked by stimulation of the mental nerve during maximal clenching of the teeth. The extent of the lesions

  9. Auditory Brainstem Response to Complex Sounds Predicts Self-Reported Speech-in-Noise Performance

    Science.gov (United States)

    Anderson, Samira; Parbery-Clark, Alexandra; White-Schwoch, Travis; Kraus, Nina

    2013-01-01

    Purpose: To compare the ability of the auditory brainstem response to complex sounds (cABR) to predict subjective ratings of speech understanding in noise on the Speech, Spatial, and Qualities of Hearing Scale (SSQ; Gatehouse & Noble, 2004) relative to the predictive ability of the Quick Speech-in-Noise test (QuickSIN; Killion, Niquette,…

  10. Speech-evoked brainstem frequency-following responses during verbal transformations due to word repetition.

    Science.gov (United States)

    Galbraith, G C; Jhaveri, S P; Kuo, J

    1997-01-01

    Speech-evoked brainstem frequency-following responses (FFRs) were recorded to repeated presentations of the same stimulus word. Word repetition results in illusory verbal transformations (VTs) in which word perceptions can differ markedly from the actual stimulus. Previous behavioral studies support an explanation of VTs based on changes in arousal or attention. Horizontal and vertical dipole FFRs were recorded to assess responses with putative origins in the auditory nerve and central brainstem, respectively. FFRs were recorded from 18 subjects when they correctly heard the stimulus and when they reported VTs. Although horizontal and vertical dipole FFRs showed different frequency response patterns, dipoles did not differentiate between perceptual conditions. However, when subjects were divided into low- and high-VT groups (based on percentage of VT trials), a significant Condition x Group interaction resulted. This interaction showed the largest difference in FFR amplitudes during VT trials, with the low-VT group showing increased amplitudes, and the high-VT group showing decreased amplitudes, relative to trials in which the stimulus was correctly perceived. These results demonstrate measurable subject differences in the early processing of complex signals, due to possible effects of attention on the brainstem FFR. The present research shows that the FFR is useful in understanding human language as it is coded and processed in the brainstem auditory pathway.

  11. The human premotor oculomotor brainstem system - can it help to understand oculomotor symptoms in Huntington's disease?

    NARCIS (Netherlands)

    Rueb, U.; Heinsen, H.; Brunt, E. R.; Landwehrmeyer, B.; Den Dunnen, W. F. A.; Gierga, K.; Deller, T.

    Recent progress in oculomotor research has enabled new insights into the functional neuroanatomy of the human premotor oculomotor brainstem network. In the present review, we provide an overview of its functional neuroanatomy and summarize the broad range of oculomotor dysfunctions that may occur in

  12. Towards an optimal paradigm for simultaneously recording cortical and brainstem auditory evoked potentials.

    Science.gov (United States)

    Bidelman, Gavin M

    2015-02-15

    Simultaneous recording of brainstem and cortical event-related brain potentials (ERPs) may offer a valuable tool for understanding the early neural transcription of behaviorally relevant sounds and the hierarchy of signal processing operating at multiple levels of the auditory system. To date, dual recordings have been challenged by technological and physiological limitations including different optimal parameters necessary to elicit each class of ERP (e.g., differential adaptation/habitation effects and number of trials to obtain adequate response signal-to-noise ratio). We investigated a new stimulus paradigm for concurrent recording of the auditory brainstem frequency-following response (FFR) and cortical ERPs. The paradigm is "optimal" in that it uses a clustered stimulus presentation and variable interstimulus interval (ISI) to (i) achieve the most ideal acquisition parameters for eliciting subcortical and cortical responses, (ii) obtain an adequate number of trials to detect each class of response, and (iii) minimize neural adaptation/habituation effects. Comparison between clustered and traditional (fixed, slow ISI) stimulus paradigms revealed minimal change in amplitude or latencies of either the brainstem FFR or cortical ERP. The clustered paradigm offered over a 3× increase in recording efficiency compared to conventional (fixed ISI presentation) and thus, a more rapid protocol for obtaining dual brainstem-cortical recordings in individual listeners. We infer that faster recording of subcortical and cortical potentials might allow more complete and sensitive testing of neurophysiological function and aid in the differential assessment of auditory function. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Identification of clinical target areas in the brainstem of prion‐infected mice

    Science.gov (United States)

    Mirabile, Ilaria; Jat, Parmjit S.; Brandner, Sebastian

    2015-01-01

    Aims While prion infection ultimately involves the entire brain, it has long been thought that the abrupt clinical onset and rapid neurological decline in laboratory rodents relates to involvement of specific critical neuroanatomical target areas. The severity and type of clinical signs, together with the rapid progression, suggest the brainstem as a candidate location for such critical areas. In this study we aimed to correlate prion pathology with clinical phenotype in order to identify clinical target areas. Method We conducted a comprehensive survey of brainstem pathology in mice infected with two distinct prion strains, which produce different patterns of pathology, in mice overexpressing prion protein (with accelerated clinical onset) and in mice in which neuronal expression was reduced by gene targeting (which greatly delays clinical onset). Results We identified specific brainstem areas that are affected by prion pathology during the progression of the disease. In the early phase of disease the locus coeruleus, the nucleus of the solitary tract, and the pre‐Bötzinger complex were affected by prion protein deposition. This was followed by involvement of the motor and autonomic centres of the brainstem. Conclusions Neurodegeneration in the locus coeruleus, the nucleus of the solitary tract and the pre‐Bötzinger complex predominated and corresponded to the manifestation of the clinical phenotype. Because of their fundamental role in controlling autonomic function and the overlap with clinical signs in sporadic Creutzfeldt–Jakob disease, we suggest that these nuclei represent key clinical target areas in prion diseases. PMID:25311251

  14. Low-frequency versus high-frequency synchronisation in chirp-evoked auditory brainstem responses

    DEFF Research Database (Denmark)

    Rønne, Filip Munch; Gøtsche-Rasmussen, Kristian

    2011-01-01

    This study investigates the frequency specific contribution to the auditory brainstem response (ABR) of chirp stimuli. Frequency rising chirps were designed to compensate for the cochlear traveling wave delay, and lead to larger wave-V amplitudes than for click stimuli as more auditory nerve fibr...

  15. Boxing sparring complicated by an acute subdural haematoma and brainstem haemorrhage.

    Science.gov (United States)

    Hart, Michael G; Trivedi, Rikin A; Hutchinson, Peter J

    2012-10-01

    A professional boxer developed an acute subdural haematoma after boxing sparring. Despite timely surgical decompression, he had a poor overall outcome predominantly from a delayed brainstem haematoma. Magnetic resonance imaging (MRI) was used to elucidate the pathophysiology of the patients' injury and clinical condition.

  16. Adaptive hypofractionated gamma knife radiosurgery for a large brainstem metastasis

    DEFF Research Database (Denmark)

    Sinclair, Georges; Bartek, Jiri; Martin, Heather

    2016-01-01

    cancer in July 2011, initially treated with chemotherapy and tyrosine kinase inhibitors, developed multiple brain metastases March 2013, with subsequent whole brain radiotherapy, after which a magnetic resonance imaging (MRI) showed a significant volume regression of all brain metastases. A follow-up MRI...... adaptive hypofractionation proved to be effective to achieve tumor control while limiting local adverse reactions. This surgical modality should be considered when managing larger brain lesions in critical areas....

  17. Relationship Between Lifelong Exercise Volume and Coronary Atherosclerosis in Athletes.

    Science.gov (United States)

    Aengevaeren, Vincent L; Mosterd, Arend; Braber, Thijs L; Prakken, Niek H J; Doevendans, Pieter A; Grobbee, Diederick E; Thompson, Paul D; Eijsvogels, Thijs M H; Velthuis, Birgitta K

    2017-07-11

    Higher levels of physical activity are associated with a lower risk of cardiovascular events. Nevertheless, there is debate on the dose-response relationship of exercise and cardiovascular disease outcomes and whether high volumes of exercise may accelerate coronary atherosclerosis. We aimed to determine the relationship between lifelong exercise volumes and coronary atherosclerosis. Middle-aged men engaged in competitive or recreational leisure sports underwent a noncontrast and contrast-enhanced computed tomography scan to assess coronary artery calcification (CAC) and plaque characteristics. Participants reported lifelong exercise history patterns. Exercise volumes were multiplied by metabolic equivalent of task (MET) scores to calculate MET-minutes per week. Participants' activity was categorized as 2000 MET-min/wk. A total of 284 men (age, 55±7 years) were included. CAC was present in 150 of 284 participants (53%) with a median CAC score of 35.8 (interquartile range, 9.3-145.8). Athletes with a lifelong exercise volume >2000 MET-min/wk (n=75) had a significantly higher CAC score (9.4 [interquartile range, 0-60.9] versus 0 [interquartile range, 0-43.5]; P =0.02) and prevalence of CAC (68%; adjusted odds ratio [OR adjusted ]=3.2; 95% confidence interval [CI], 1.6-6.6) and plaque (77%; OR adjusted =3.3; 95% CI, 1.6-7.1) compared with exercise (≥9 MET) was associated with CAC (OR adjusted =1.47; 95% CI, 1.14-1.91) and plaque (OR adjusted =1.56; 95% CI, 1.17-2.08). Among participants with CAC>0, there was no difference in CAC score ( P =0.20), area ( P =0.21), density ( P =0.25), and regions of interest ( P =0.20) across exercise volume groups. Among participants with plaque, the most active group (>2000 MET-min/wk) had a lower prevalence of mixed plaques (48% versus 69%; OR adjusted =0.35; 95% CI, 0.15-0.85) and more often had only calcified plaques (38% versus 16%; OR adjusted =3.57; 95% CI, 1.28-9.97) compared with the least active group (2000 MET

  18. The formation of atherosclerotic plaque, its destabilisation and diagnostics

    Directory of Open Access Journals (Sweden)

    Piotr Kaźmierski

    2014-04-01

    Full Text Available According to the established medical knowledge, the atheromatous lesions occur in the arteries of large and medium diameter. Their presence in the aorta, arteries of extremities as well as extracerebral and coronal arteries is clinically relevant. The evolution of atherosclerotic plaques probably starts in the prenatal development, what may be proved by the presence of the fatty streaks in endothelium of coronal arteries in some newborns. Then it evolves through lipid accumulation, media inflammatory response, vasa vasorum proliferation, fibrination and calcification of plaques. Researches proved that the matter of atherosclerosis is exaggerated inflammatory proliferative reaction to the arterial wall damage. The oxidative stress phenomenon and infections with common pathogens play an undoubtful role in this process. Ultimately the direct damage is an effect of immune response cells infiltration and secretion of cytokines and proinflammatory factors. Among the cells of immune system responsible for formation and development of atheromatous plaque are considered: macrophages, dendritic cells, T and B lymphocytes, monocytes. Attention was also paid to the inflammatory mediators and growth factors. Scientist are interested in unstable atherosclerotic plaque and accompanying inflammatory process within the artery wall for a long time. Meanwhile, there are conducted researches on inflammation markers underlying the destabilisation of plaques. Revealing the role of these cells in evolution of atherosclerosis would enable more complex understanding of the mechanism of lesions development. Then it would facilitate an introduction of the new and upgraded methods of treatment and prevention. Also the progress of imaging examinations is meaningful for diagnostics and treatment. It is contributory to the choice of therapeutic strategy and assessment of surgical intervention urgency. In the clinical practice there are recognized standards of imaging the

  19. Acid production in dental plaque after exposure to probiotic bacteria

    Directory of Open Access Journals (Sweden)

    Keller Mette K

    2012-10-01

    Full Text Available Abstract Background The increasing interest in probiotic lactobacilli in health maintenance has raised the question of potential risks. One possible side effect could be an increased acidogenicity in dental plaque. The aim of this study was to investigate the effect of probiotic lactobacilli on plaque lactic acid (LA production in vitro and in vivo. Methods In the first part (A, suspensions of two lactobacilli strains (L. reuteri DSM 17938, L. plantarum 299v were added to suspensions of supragingival dental plaque collected from healthy young adults (n=25. LA production after fermentation with either xylitol or fructose was analyzed. In the second part (B, subjects (n=18 were given lozenges with probiotic lactobacilli (L. reuteri DSM 17938 and ATCC PTA 5289 or placebo for two weeks in a double-blinded, randomized cross-over trial. The concentration of LA in supragingival plaque samples was determined at baseline and after 2 weeks. Salivary counts of mutans streptococci (MS and lactobacilli were estimated with chair-side methods. Results Plaque suspensions with L. reuteri DSM 17938 produced significantly less LA compared with L. plantarum 299v or controls (p Conclusion Lactic acid production in suspensions of plaque and probiotic lactobacilli was strain-dependant and the present study provides no evidence of an increase in plaque acidity by the supply of selected probiotic lactobacilli when challenged by fructose or xylitol. The study protocol was approved by The Danish National Committee on Biomedical Research Ethics (protocol no H-2-2010-112. Trial registration NCT01700712

  20. Raised soluble P-selectin moderately accelerates atherosclerotic plaque progression.

    Directory of Open Access Journals (Sweden)

    Kevin J Woollard

    Full Text Available Soluble P-selectin (sP-selectin, a biomarker of inflammatory related pathologies including cardiovascular and peripheral vascular diseases, also has pro-atherosclerotic effects including the ability to increase leukocyte recruitment and modulate thrombotic responses in vivo. The current study explores its role in progressing atherosclerotic plaque disease. Apoe-/- mice placed on a high fat diet (HFD were given daily injections of recombinant dimeric murine P-selectin (22.5 µg/kg/day for 8 or 16 weeks. Saline or sE-selectin injections were used as negative controls. In order to assess the role of sP-selectin on atherothrombosis an experimental plaque remodelling murine model, with sm22α-hDTR Apoe-/- mice on a HFD in conjunction with delivery of diphtheria toxin to induce targeted vascular smooth muscle apoptosis, was used. These mice were similarly given daily injections of sP-selectin for 8 or 16 weeks. While plaque mass and aortic lipid content did not change with sP-selectin treatment in Apoe-/- or SM22α-hDTR Apoe-/- mice on HFD, increased plasma MCP-1 and a higher plaque CD45 content in Apoe-/- HFD mice was observed. As well, a significant shift towards a more unstable plaque phenotype in the SM22α-hDTR Apoe-/- HFD mice, with increased macrophage accumulation and lower collagen content, leading to a lower plaque stability index, was observed. These results demonstrate that chronically raised sP-selectin favours progression of an unstable atherosclerotic plaque phenotype.

  1. Advanced computed tomographic anatomical and morphometric plaque analysis for prediction of fractional flow reserve in intermediate coronary lesions

    International Nuclear Information System (INIS)

    Opolski, Maksymilian P.; Kepka, Cezary; Achenbach, Stephan; Pregowski, Jerzy; Kruk, Mariusz; Staruch, Adam D.; Kadziela, Jacek; Ruzyllo, Witold; Witkowski, Adam

    2014-01-01

    Objective: To determine the application of advanced coronary computed tomography angiography (CCTA) plaque analysis for predicting invasive fractional flow reserve (FFR) in intermediate coronary lesions. Methods: Sixty-one patients with 71 single intermediate coronary lesions (≥50–80% stenosis) on CCTA prospectively underwent coronary angiography and FFR. Advanced anatomical and morphometric plaque analysis was performed based on CCTA data set to determine optimal criteria for significant flow impairment. A significant stenosis was defined as FFR ≤ 0.80. Results: FFR averaged 0.85 ± 0.09, and 19 lesions (27%) were functionally significant. FFR correlated with minimum lumen area (MLA) (r = 0.456, p < 0.001), minimum lumen diameter (MLD) (r = 0.326, p = 0.006), reference lumen diameter (RLD) (r = 0.245, p = 0.039), plaque burden (r = −0.313, p = 0.008), lumen area stenosis (r = −0.305, p = 0.01), lesion length (r = −0.692, p < 0.001), and plaque volume (r = −0.668, p < 0.001). There was no relationship between FFR and CCTA morphometric plaque parameters. By multivariate analysis the independent predictors of FFR were lesion length (beta = −0.581, p < 0.001), MLA (beta = 0.360, p = 0.041), and RLD (beta = −0.255, p = 0.036). The optimal cutoffs for lesion length, MLA, MLD, RLD, and lumen area stenosis were >18.5 mm, ≤3.0 mm 2 , ≤2.1 mm, ≤3.2 mm, and >69%, respectively (max. sensitivity: 100% for MLA, max. specificity: 79% for lumen area stenosis). Conclusions: CCTA predictors for FFR support the mathematical relationship between stenosis pressure drop and coronary flow. CCTA could prove to be a useful rule-out test for significant hemodynamic effects of intermediate coronary stenoses

  2. Intermittent hypercapnic hypoxia effects on the nicotinic acetylcholine receptors in the developing piglet hippocampus and brainstem.

    Science.gov (United States)

    Vivekanandarajah, Arunnjah; Aishah, Atqiya; Waters, Karen A; Machaalani, Rita

    2017-05-01

    This study investigated the effects of acute (1 day) vs repeated (4 days) exposure to intermittent hypercapnic hypoxia (IHH) on the immunohistochemical expression of α2, α3, α5, α7, α9 and β2 nicotinic acetylcholine receptor (nAChR) subunits in the developing piglet hippocampus and brainstem medulla, and how prior nicotine exposure alters the response to acute IHH. Five piglet groups included: 1day IHH (1D IHH, n=9), 4days IHH (4D IHH, n=8), controls exposed only to air cycles for 1day (1D Air, n=6) or 4days (4D Air, n=5), and pre-exposed to nicotine for 13days prior to 1day IHH (Nic+1D IHH, n=7). The exposure period alternated 6min of HH (8%O 2 , 7%CO 2 , balance N 2 ) and 6min of air over 48min, while controls were switched from air-to-air. Results showed that: 1. repeated IHH induces more changes in nAChR subunit expression than acute IHH in both the hippocampus and brainstem medulla, 2. In the hippocampus, α2 and β2 changed the most (increased) following IHH and the CA3, CA2 and DG were mostly affected. In the brainstem medulla, α2, α5, α9 and β2 were changed (decreased) in most nuclei with the hypoglossal and nucleus of the solitary tract being mostly affected. 3. Pre-exposure to nicotine enhanced the changes in the hippocampus but dampened those in the brainstem medulla. These findings indicate that the nAChRs (predominantly with the α2/β2 complex) are affected by IHH in critical hippocampal and brainstem nuclei during early brain development, and that pre-exposure to nicotine alters the pattern of susceptibility to IHH. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Characterising Ageing in the Human Brainstem Using Quantitative Multimodal MRI Analysis

    Directory of Open Access Journals (Sweden)

    Christian eLambert

    2013-08-01

    Full Text Available Ageing is ubiquitous to the human condition. The MRI correlates of healthy ageing have been extensively investigated using a range of modalities, including volumetric MRI, quantitative MRI and DTI. Despite this, the reported brainstem related changes remain sparse. This is, in part, due to the technical and methodological limitations in quantitatively assessing and statistically analysing this region. By utilising a new method of brainstem segmentation, a large cohort of 100 healthy adults were assessed in this study for the effects of ageing within the human brainstem in vivo. Using quantitative MRI (qMRI, tensor based morphometry (TBM and voxel based quantification (VBQ, the volumetric and quantitative changes across healthy adults between 19-75 years were characterised. In addition to the increased R2* in substantia nigra corresponding to increasing iron deposition with age, several novel findings were reported in the current study. These include selective volumetric loss of the brachium conjunctivum, with a corresponding decrease in magnetisation transfer (MT and increase in proton density (PD, accounting for the previously described midbrain shrinkage. Additionally, we found increases in R1 and PD in several pontine and medullary structures. We consider these changes in the context of well-characterised, functional age-related changes, and propose potential biophysical mechanisms. This study provides detailed quantitative analysis of the internal architecture of the brainstem and provides a baseline for further studies of neurodegenerative diseases that are characterised by early, pre-clinical involvement of the brainstem, such as Parkinson’s and Alzheimer’s diseases.

  4. Robust Machine Learning-Based Correction on Automatic Segmentation of the Cerebellum and Brainstem.

    Science.gov (United States)

    Wang, Jun Yi; Ngo, Michael M; Hessl, David; Hagerman, Randi J; Rivera, Susan M

    2016-01-01

    Automated segmentation is a useful method for studying large brain structures such as the cerebellum and brainstem. However, automated segmentation may lead to inaccuracy and/or undesirable boundary. The goal of the present study was to investigate whether SegAdapter, a machine learning-based method, is useful for automatically correcting large segmentation errors and disagreement in anatomical definition. We further assessed the robustness of the method in handling size of training set, differences in head coil usage, and amount of brain atrophy. High resolution T1-weighted images were acquired from 30 healthy controls scanned with either an 8-channel or 32-channel head coil. Ten patients, who suffered from brain atrophy because of fragile X-associated tremor/ataxia syndrome, were scanned using the 32-channel head coil. The initial segmentations of the cerebellum and brainstem were generated automatically using Freesurfer. Subsequently, Freesurfer's segmentations were both manually corrected to serve as the gold standard and automatically corrected by SegAdapter. Using only 5 scans in the training set, spatial overlap with manual segmentation in Dice coefficient improved significantly from 0.956 (for Freesurfer segmentation) to 0.978 (for SegAdapter-corrected segmentation) for the cerebellum and from 0.821 to 0.954 for the brainstem. Reducing the training set size to 2 scans only decreased the Dice coefficient ≤0.002 for the cerebellum and ≤ 0.005 for the brainstem compared to the use of training set size of 5 scans in corrective learning. The method was also robust in handling differences between the training set and the test set in head coil usage and the amount of brain atrophy, which reduced spatial overlap only by segmentation and corrective learning provides a valuable method for accurate and efficient segmentation of the cerebellum and brainstem, particularly in large-scale neuroimaging studies, and potentially for segmenting other neural regions as

  5. Four cases with localized brain-stem lesion on CT scan following closed head injury

    International Nuclear Information System (INIS)

    Saeki, Naokatsu; Odaki, Masaru; Oka, Nobuo; Takase, Manabu; Ono, Junichi.

    1981-01-01

    Cases of primary brain-stem injury following closed head injury, verified by a CT scan, have been increasingly reported. However, most of them have other intracranial lesions in addition to the brain stem, resulting in a poor outcome. The CT scan of 200 cases with severe head injury-Araki's classification of types 3 and 4 - were analysed. Four cases out of them had localized brain-stem lesion without any other significant intracranial injury on a CT scan at the acute stage and had a better outcome than had previously been reported. In this analysis, these 4 cases were studied, and the CT findings, prognosis, and pathogenesis of the localized brain-stem injury were discussed. Follow-up CT of three cases, and taken one month or more later, showed diffuse cortical atrophy. This may indicate the presence of diffuse cerebral injury which could not be seen on CT scans at the acute stage. This atrophic change may also be related with the mechanism of posttraumatic conscious impairment and posttraumatic neurological deficits, such as mental symptoms and impairment of the higher cortical function. Shearing injury is a probable pathogenesis for this diffuse cortical injury. On the other hand, one case did not have any cortical atrophy on a follow-up CT scan. Therefore, this is a case with a localized primary brain-stem injury. Coup injury against the brain stem by a tentorial margin in a case with a small tentorial opening is a possible mechanism producing the localized brain-stem injury. (J.P.N.)

  6. Evaluation of peripheral auditory pathways and brainstem in obstructive sleep apnea

    Directory of Open Access Journals (Sweden)

    Erika Matsumura

    Full Text Available Abstract Introduction Obstructive sleep apnea causes changes in normal sleep architecture, fragmenting it chronically with intermittent hypoxia, leading to serious health consequences in the long term. It is believed that the occurrence of respiratory events during sleep, such as apnea and hypopnea, can impair the transmission of nerve impulses along the auditory pathway that are highly dependent on the supply of oxygen. However, this association is not well established in the literature. Objective To compare the evaluation of peripheral auditory pathway and brainstem among individuals with and without obstructive sleep apnea. Methods The sample consisted of 38 adult males, mean age of 35.8 (±7.2, divided into four groups matched for age and Body Mass Index. The groups were classified based on polysomnography in: control (n = 10, mild obstructive sleep apnea (n = 11 moderate obstructive sleep apnea (n = 8 and severe obstructive sleep apnea (n = 9. All study subjects denied a history of risk for hearing loss and underwent audiometry, tympanometry, acoustic reflex and Brainstem Auditory Evoked Response. Statistical analyses were performed using three-factor ANOVA, 2-factor ANOVA, chi-square test, and Fisher's exact test. The significance level for all tests was 5%. Results There was no difference between the groups for hearing thresholds, tympanometry and evaluated Brainstem Auditory Evoked Response parameters. An association was observed between the presence of obstructive sleep apnea and changes in absolute latency of wave V (p = 0.03. There was an association between moderate obstructive sleep apnea and change of the latency of wave V (p = 0.01. Conclusion The presence of obstructive sleep apnea is associated with changes in nerve conduction of acoustic stimuli in the auditory pathway in the brainstem. The increase in obstructive sleep apnea severity does not promote worsening of responses assessed by audiometry, tympanometry and Brainstem

  7. 7 Tesla 22-channel wrap-around coil array for cervical spinal cord and brainstem imaging.

    Science.gov (United States)

    Zhang, Bei; Seifert, Alan C; Kim, Joo-Won; Borrello, Joseph; Xu, Junqian

    2017-10-01

    Increased signal-to-noise ratio and blood oxygenation level-dependent sensitivity at 7 Tesla (T) have the potential to enable high-resolution imaging of the human cervical spinal cord and brainstem. We propose a new two-panel radiofrequency coil design for these regions to fully exploit the advantages of ultra-high field. A two-panel array, containing four transmit/receive and 18 receive-only elements fully encircling the head and neck, was constructed following simulations demonstrating the B1+ and specific absorption rate (SAR) benefits of two-panel over one-panel arrays. This array was compared with a previously reported posterior-only array and tested for safety using a phantom. Its anatomical, functional, and diffusion MRI performance was demonstrated in vivo. The two-panel array produced more uniform B1+ across the brainstem and cervical spinal cord without compromising SAR, and achieved 70% greater receive sensitivity than the posterior-only array. The two-panel design enabled acceleration of R = 2 × 2 in two dimensions or R = 3 in a single dimension. High quality in vivo anatomical, functional, and diffusion images of the human cervical spinal cord and brainstem were acquired. We have designed and constructed a wrap-around coil array with excellent performance for cervical spinal cord and brainstem MRI at 7T, which enables simultaneous human cervical spinal cord and brainstem functional MRI. Magn Reson Med 78:1623-1634, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2016 International Society for Magnetic Resonance in Medicine.

  8. Macrovascular Decompression of the Brainstem and Cranial Nerves: Evolution of an Anteromedial Vertebrobasilar Artery Transposition Technique.

    Science.gov (United States)

    Choudhri, Omar; Connolly, Ian D; Lawton, Michael T

    2017-08-01

    Tortuous and dolichoectatic vertebrobasilar arteries can impinge on the brainstem and cranial nerves to cause compression syndromes. Transposition techniques are often required to decompress the brainstem with dolichoectatic pathology. We describe our evolution of an anteromedial transposition technique and its efficacy in decompressing the brainstem and relieving symptoms. To present the anteromedial vertebrobasilar artery transposition technique for macrovascular decompression of the brainstem and cranial nerves. All patients who underwent vertebrobasilar artery transposition were identified from the prospectively maintained database of the Vascular Neurosurgery service, and their medical records were reviewed retrospectively. The extent of arterial displacement was measured pre- and postoperatively on imaging. Vertebrobasilar arterial transposition and macrovascular decompression was performed in 12 patients. Evolution in technique was characterized by gradual preference for the far-lateral approach, use of a sling technique with muslin wrap, and an anteromedial direction of pull on the vertebrobasilar artery with clip-assisted tethering to the clival dura. With this technique, mean lateral displacement decreased from 6.6 mm in the first half of the series to 3.8 mm in the last half of the series, and mean anterior displacement increased from 0.8 to 2.5 mm, with corresponding increases in satisfaction and relief of symptoms. Compressive dolichoectatic pathology directed laterally into cranial nerves and posteriorly into the brainstem can be corrected with anteromedial transposition towards the clivus. Our technique accomplishes this anteromedial transposition from an inferolateral surgical approach through the vagoaccessory triangle, with sling fixation to clival dura using aneurysm clips. Copyright © 2017 by the Congress of Neurological Surgeons

  9. Evaluation of peripheral auditory pathways and brainstem in obstructive sleep apnea.

    Science.gov (United States)

    Matsumura, Erika; Matas, Carla Gentile; Magliaro, Fernanda Cristina Leite; Pedreño, Raquel Meirelles; Lorenzi-Filho, Geraldo; Sanches, Seisse Gabriela Gandolfi; Carvallo, Renata Mota Mamede

    2016-11-25

    Obstructive sleep apnea causes changes in normal sleep architecture, fragmenting it chronically with intermittent hypoxia, leading to serious health consequences in the long term. It is believed that the occurrence of respiratory events during sleep, such as apnea and hypopnea, can impair the transmission of nerve impulses along the auditory pathway that are highly dependent on the supply of oxygen. However, this association is not well established in the literature. To compare the evaluation of peripheral auditory pathway and brainstem among individuals with and without obstructive sleep apnea. The sample consisted of 38 adult males, mean age of 35.8 (±7.2), divided into four groups matched for age and Body Mass Index. The groups were classified based on polysomnography in: control (n=10), mild obstructive sleep apnea (n=11) moderate obstructive sleep apnea (n=8) and severe obstructive sleep apnea (n=9). All study subjects denied a history of risk for hearing loss and underwent audiometry, tympanometry, acoustic reflex and Brainstem Auditory Evoked Response. Statistical analyses were performed using three-factor ANOVA, 2-factor ANOVA, chi-square test, and Fisher's exact test. The significance level for all tests was 5%. There was no difference between the groups for hearing thresholds, tympanometry and evaluated Brainstem Auditory Evoked Response parameters. An association was observed between the presence of obstructive sleep apnea and changes in absolute latency of wave V (p=0.03). There was an association between moderate obstructive sleep apnea and change of the latency of wave V (p=0.01). The presence of obstructive sleep apnea is associated with changes in nerve conduction of acoustic stimuli in the auditory pathway in the brainstem. The increase in obstructive sleep apnea severity does not promote worsening of responses assessed by audiometry, tympanometry and Brainstem Auditory Evoked Response. Copyright © 2016 Associação Brasileira de

  10. 14C-dopamine microinjected into the brain-stem of the rat: dispersion kinetics, site content and functional dose

    International Nuclear Information System (INIS)

    Myers, R.D.; Hoch, D.B.

    1978-01-01

    A morphological analysis was undertaken of both the dispersion characteristics and tissue content of dopamine (DA) microinjected acutely into the brain-stem of the anesthetized rat. 14C-DA, with a specific activity of 56-62 mCi/mMol, was infused unilaterally into the pars compacta of the substantia nigra in one of four test volumes: 0.5, 1.0, 4.0 or 8.0 microliters. The concentration of the 14C-DA solution was 1.0 microCi/microliter, equivalent to 3.01 micrograms/microliters, which was delivered at an injection rate of 1.0 microliter per 45 sec. At an interval of either one min or 15 min following the microinjection, the rat's brain was removed rapidly from its calvarium, flash frozen and then cut in the coronal plane on a freezing microtome in 500 micron slabs. After each of the respective serial slabs was mounted on glass, the Eik Nes-Brizzee trochar technique for the discrete removal of tissue samples was used to obtain 0.5 mm dia. cylindrical plugs of meso-diencephalic tissue at distances from the site of injection ranging from 0.5 to 2.5 mm, center to center. Each sample plug was subsequently solubilized and 14C-DA activity quantitated by liquid scintillation spectrometry. The results show that regardless of volume, the spatial patterning of the microinjected solution assumes a tear-drop or pear shape, not a sphere. Further, as the volume of the injection is increased from 0.5 to 8.0 microliters, the magnitude of the dispersion of 14C-DA is enhanced throughout the surrounding parenchyma, but not in a linear fashion

  11. Model-based dose calculations for COMS eye plaque brachytherapy using an anatomically realistic eye phantom.

    Science.gov (United States)

    Lesperance, Marielle; Inglis-Whalen, M; Thomson, R M

    2014-02-01

    To investigate the effects of the composition and geometry of ocular media and tissues surrounding the eye on dose distributions for COMS eye plaque brachytherapy with(125)I, (103)Pd, or (131)Cs seeds, and to investigate doses to ocular structures. An anatomically and compositionally realistic voxelized eye model with a medial tumor is developed based on a literature review. Mass energy absorption and attenuation coefficients for ocular media are calculated. Radiation transport and dose deposition are simulated using the EGSnrc Monte Carlo user-code BrachyDose for a fully loaded COMS eye plaque within a water phantom and our full eye model for the three radionuclides. A TG-43 simulation with the same seed configuration in a water phantom neglecting the plaque and interseed effects is also performed. The impact on dose distributions of varying tumor position, as well as tumor and surrounding tissue media is investigated. Each simulation and radionuclide is compared using isodose contours, dose volume histograms for the lens and tumor, maximum, minimum, and average doses to structures of interest, and doses to voxels of interest within the eye. Mass energy absorption and attenuation coefficients of the ocular media differ from those of water by as much as 12% within the 20-30 keV photon energy range. For all radionuclides studied, average doses to the tumor and lens regions in the full eye model differ from those for the plaque in water by 8%-10% and 13%-14%, respectively; the average doses to the tumor and lens regions differ between the full eye model and the TG-43 simulation by 2%-17% and 29%-34%, respectively. Replacing the surrounding tissues in the eye model with water increases the maximum and average doses to the lens by 2% and 3%, respectively. Substituting the tumor medium in the eye model for water, soft tissue, or an alternate melanoma composition affects tumor dose compared to the default eye model simulation by up to 16%. In the full eye model

  12. Model-based dose calculations for COMS eye plaque brachytherapy using an anatomically realistic eye phantom

    International Nuclear Information System (INIS)

    Lesperance, Marielle; Inglis-Whalen, M.; Thomson, R. M.

    2014-01-01

    Purpose : To investigate the effects of the composition and geometry of ocular media and tissues surrounding the eye on dose distributions for COMS eye plaque brachytherapy with 125 I, 103 Pd, or 131 Cs seeds, and to investigate doses to ocular structures. Methods : An anatomically and compositionally realistic voxelized eye model with a medial tumor is developed based on a literature review. Mass energy absorption and attenuation coefficients for ocular media are calculated. Radiation transport and dose deposition are simulated using the EGSnrc Monte Carlo user-code BrachyDose for a fully loaded COMS eye plaque within a water phantom and our full eye model for the three radionuclides. A TG-43 simulation with the same seed configuration in a water phantom neglecting the plaque and interseed effects is also performed. The impact on dose distributions of varying tumor position, as well as tumor and surrounding tissue media is investigated. Each simulation and radionuclide is compared using isodose contours, dose volume histograms for the lens and tumor, maximum, minimum, and average doses to structures of interest, and doses to voxels of interest within the eye. Results : Mass energy absorption and attenuation coefficients of the ocular media differ from those of water by as much as 12% within the 20–30 keV photon energy range. For all radionuclides studied, average doses to the tumor and lens regions in the full eye model differ from those for the plaque in water by 8%–10% and 13%–14%, respectively; the average doses to the tumor and lens regions differ between the full eye model and the TG-43 simulation by 2%–17% and 29%–34%, respectively. Replacing the surrounding tissues in the eye model with water increases the maximum and average doses to the lens by 2% and 3%, respectively. Substituting the tumor medium in the eye model for water, soft tissue, or an alternate melanoma composition affects tumor dose compared to the default eye model simulation by up

  13. Identifying Vulnerable Plaques with Acoustic Radiation Force Impulse Imaging

    Science.gov (United States)

    Doherty, Joshua Ryan

    The rupture of arterial plaques is the most common cause of ischemic complications including stroke, the fourth leading cause of death and number one cause of long term disability in the United States. Unfortunately, because conventional diagnostic tools fail to identify plaques that confer the highest risk, often a disabling stroke and/or sudden death is the first sign of disease. A diagnostic method capable of characterizing plaque vulnerability would likely enhance the predictive ability and ultimately the treatment of stroke before the onset of clinical events. This dissertation evaluates the hypothesis that Acoustic Radiation Force Impulse (ARFI) imaging can noninvasively identify lipid regions, that have been shown to increase a plaque's propensity to rupture, within carotid artery plaques in vivo. The work detailed herein describes development efforts and results from simulations and experiments that were performed to evaluate this hypothesis. To first demonstrate feasibility and evaluate potential safety concerns, finite- element method simulations are used to model the response of carotid artery plaques to an acoustic radiation force excitation. Lipid pool visualization is shown to vary as a function of lipid pool geometry and stiffness. A comparison of the resulting Von Mises stresses indicates that stresses induced by an ARFI excitation are three orders of magnitude lower than those induced by blood pressure. This thesis also presents the development of a novel pulse inversion harmonic tracking method to reduce clutter-imposed errors in ultrasound-based tissue displacement estimates. This method is validated in phantoms and was found to reduce bias and jitter displacement errors for a marked improvement in image quality in vivo. Lastly, this dissertation presents results from a preliminary in vivo study that compares ARFI imaging derived plaque stiffness with spatially registered composition determined by a Magnetic Resonance Imaging (MRI) gold standard

  14. Effect of baking soda in dentifrices on plaque removal.

    Science.gov (United States)

    Myneni, Srinivas R

    2017-11-01

    The prevention of dental caries and periodontal diseases targets control of dental plaque biofilm. In this context, chemical agents could represent a valuable complement to mechanical plaque control by reducing and controlling biofilm formation. The literature on the effectiveness of different dentifrices has not, however, been carefully categorized. A lack of consensus exists among dental professionals on a recommendation for a universal dentifrice for plaque control. The authors reviewed the scientific data on the different properties of sodium bicarbonate (baking soda)-containing dentifrices and their effectiveness in plaque removal. The results of the literature search show that baking soda-containing dentifrices are ideal candidates to be considered as a universal dentifrice because baking soda is inexpensive, abundant in supply, highly biocompatible, exhibits specific antibacterial properties to oral microorganisms, has low abrasivity, and is effective in plaque biofilm removal. Although some patients may benefit from desensitizing or high fluoride-containing dentifrices, those with routine needs may find using dentifrices containing baking soda and fluoride effective. Baking soda and fluoride dentifrices, therefore, may perhaps be considered as a criterion standard for patients with routine oral hygiene needs. Copyright © 2017 American Dental Association. Published by Elsevier Inc. All rights reserved.

  15. Arsenic rich iron plaque on macrophyte roots - an ecotoxicological risk?

    International Nuclear Information System (INIS)

    Taggart, M.A.; Mateo, R.; Charnock, J.M.; Bahrami, F.; Green, A.J.; Meharg, A.A.

    2009-01-01

    Arsenic is known to accumulate with iron plaque on macrophyte roots. Three to four years after the Aznalcollar mine spill (Spain), residual arsenic contamination left in seasonal wetland habitats has been identified in this form by scanning electron microscopy. Total digestion has determined arsenic concentrations in thoroughly washed 'root + plaque' material in excess of 1000 mg kg -1 , and further analysis using X-ray absorption spectroscopy suggests arsenic exists as both arsenate and arsenite. Certain herbivorous species feed on rhizomes and bulbs of macrophytes in a wide range of global environments, and the ecotoxicological impact of consuming arsenic rich iron plaque associated with such food items remains to be quantified. Here, greylag geese which feed on Scirpus maritimus rhizome and bulb material in areas affected by the Aznalcollar spill are shown to have elevated levels of arsenic in their feces, which may originate from arsenic rich iron plaque. - Accumulation of metals with iron plaque on macrophyte roots in wetlands poses an ecotoxicological risk to certain herbivores

  16. Protein components in saliva and plaque fluid from irradiated primates

    Energy Technology Data Exchange (ETDEWEB)

    Edgar, W.M.; Bowen, W.H.; Cole, M.F. (Caries Prevention and Research Branch, National Caries Program, NIDR, Bethesda, Maryland, USA)

    1982-01-01

    Irradiation of the major salivary glands of monkeys (Macaca mulatta) fed cariogenic diets leads to caries clinically indistinguishable from radiation caries in man. This study compares the organic compostion of individual samples of plaque fluid and saliva from irradiated and control monkeys receiving the same cariogenic diet. Plaque and saliva were collected from fasting, tranquillised animals. Four irradiated animals were sampled repeatedly as were non-irradiated controls. Total protein, albumin, immunoglobulins A, G, and M, and the third component of complement (C'3) were quantitated in plaque fluid and whole saliva. Salivary amylase and peroxidase activities were also determined. Plaque fluid and saliva samples were also subjected to polyacrylamide gel electrophoresis. The total viable anaerobic count and numbers of Streptococcus mutans were determined in samples of plaque. The results suggest that the major effect of irradiation leading to increased numbers of S. mutans and caries susceptibility is in the amount, and not the composition, of the saliva produced by the residual gland tissue. The scanty flow of saliva may reduce the effectiveness of cleansing, buffering and lubrication mechanisms as well as resulting in a marked reduction in the total amount of specific and non-specific immune factors entering the mouth.

  17. Arsenic rich iron plaque on macrophyte roots - an ecotoxicological risk?

    Energy Technology Data Exchange (ETDEWEB)

    Taggart, M.A. [School of Biological Sciences, University of Aberdeen, Cruickshank Bld, St Machar Drive, Aberdeen, AB24 3UU (United Kingdom); Instituto de Investigacion en Recursos Cinegeticos, IREC (CSIC-UCLM-JCCM), Ronda de Toledo s/n, 13005 Ciudad Real (Spain)], E-mail: mark.taggart@uclm.es; Mateo, R. [Instituto de Investigacion en Recursos Cinegeticos, IREC (CSIC-UCLM-JCCM), Ronda de Toledo s/n, 13005 Ciudad Real (Spain); Charnock, J.M.; Bahrami, F. [Synchrotron Radiation Department, CCLRC Daresbury Laboratory, Warrington, Cheshire, WA4 4AD (United Kingdom); Green, A.J. [Department of Wetland Ecology, Estacion Biologica de Donana, CSIC, Pabellon del Peru, Avenida Maria Luisa s/n, 41013 Seville (Spain); Meharg, A.A. [School of Biological Sciences, University of Aberdeen, Cruickshank Bld, St Machar Drive, Aberdeen, AB24 3UU (United Kingdom)

    2009-03-15

    Arsenic is known to accumulate with iron plaque on macrophyte roots. Three to four years after the Aznalcollar mine spill (Spain), residual arsenic contamination left in seasonal wetland habitats has been identified in this form by scanning electron microscopy. Total digestion has determined arsenic concentrations in thoroughly washed 'root + plaque' material in excess of 1000 mg kg{sup -1}, and further analysis using X-ray absorption spectroscopy suggests arsenic exists as both arsenate and arsenite. Certain herbivorous species feed on rhizomes and bulbs of macrophytes in a wide range of global environments, and the ecotoxicological impact of consuming arsenic rich iron plaque associated with such food items remains to be quantified. Here, greylag geese which feed on Scirpus maritimus rhizome and bulb material in areas affected by the Aznalcollar spill are shown to have elevated levels of arsenic in their feces, which may originate from arsenic rich iron plaque. - Accumulation of metals with iron plaque on macrophyte roots in wetlands poses an ecotoxicological risk to certain herbivores.

  18. Current techniques for the investigation of vulnerable atherosclerotic plaques

    International Nuclear Information System (INIS)

    Riou, L.; Broisat, A.; Fagret, D.; Ghezzi, C.

    2005-01-01

    Atherosclerosis is the single most important contributor to cardiovascular diseases, the leading cause of death in industrialized countries. Atherosclerosis complications such as vulnerable coronary plaque rupture or erosion result in acute coronary events, i.e. myocardial infarction and sudden death. Vulnerable plaques initially develop eccentrically without impeding on the vessel lumen and are therefore not detectable using angiography. New techniques for the investigation of vulnerable plaques are needed to identify and treat vulnerable patients. Invasive techniques require the use of intracoronary probes and are thereby not applicable to large populations of patients. Intravascular ultrasound (IVUS) and optical coherence tomography (OCT) are the most promising invasive modalities. They provide morphological data that could potentially be associated with a more functional approach such as thermography, elasto-graphy, or spectroscopy, Non-invasive techniques are better suited for studying larger populations of patients. Computed tomography is currently used for calcium scoring, but the biological meaning and the prognostic value of this index remain to be fully determined. Non-invasive coronary magnetic resonance imaging (MRI) faces numerous technical challenges, and it essentially provides morphological data. Molecular nuclear imaging offers a great sensitivity and the ability to provide metabolic data about atherosclerotic lesions. New potential tracers of vulnerable plaques are currently being evaluated. Nuclear Medicine should therefore play a major role in the future as a non invasive imaging modality for the assessment of vulnerable atherosclerotic plaques. (author)

  19. Protein components in saliva and plaque fluid from irradiated primates

    International Nuclear Information System (INIS)

    Edgar, W.M.; Bowen, W.H.; Cole, M.F.

    1982-01-01

    Irradiation of the major salivary glands of monkeys (Macaca mulatta) fed cariogenic diets leads to caries clinically indistinguishable from radiation caries in man. This study compares the organic compostion of individual samples of plaque fluid and saliva from irradiated and control monkeys receiving the same cariogenic diet. Plaque and saliva were collected from fasting, tranquillised animals. Four irradiated animals were sampled repeatedly as were non-irradiated controls. Total protein, albumin, immunoglobulins A, G, and M, and the third component of complement (C'3) were quantitated in plaque fluid and whole saliva. Salivary amylase and peroxidase activities were also determined. Plaque fluid and saliva samples were also subjected to polyacrylamide gel electrophoresis. The total viable anaerobic count and numbers of Streptococcus mutans were determined in samples of plaque. The results suggest that the major effect of irradiation leading to increased numbers of S. mutans and caries susceptibility is in the amount, and not the composition, of the saliva produced by the residual gland tissue. The scanty flow of saliva may reduce the effectiveness of cleansing, buffering and lubrication mechanisms as well as resulting in a marked reduction in the total amount of specific and non-specific immune factors entering the mouth. (author)

  20. Protein components in saliva and plaque fluid from irradiated primates

    Energy Technology Data Exchange (ETDEWEB)

    Edgar, W M; Bowen, W H; Cole, M F [Caries Prevention and Research Branch, National Caries Program, NIDR, Bethesda, Maryland, USA

    1982-01-01

    Irradiation of the major salivary glands of monkeys (Macaca mulatta) fed cariogenic diets leads to caries clinically indistinguishable from radiation caries in man. This study compares the organic compostion of individual samples of plaque fluid and saliva from irradiated and control monkeys receiving the same cariogenic diet. Plaque and saliva were collected from fasting, tranquillised animals. Four irradiated animals were sampled repeatedly as were non-irradiated controls. Total protein, albumin, immunoglobulins A, G, and M, and the third component of complement (C'3) were quantitated in plaque fluid and whole saliva. Salivary amylase and peroxidase activities were also determined. Plaque fluid and saliva samples were also subjected to polyacrylamide gel electrophoresis. The total viable anaerobic count and numbers of Streptococcus mutans were determined in samples of plaque. The results suggest that the major effect of irradiation leading to increased numbers of S. mutans and caries susceptibility is in the amount, and not the composition, of the saliva produced by the residual gland tissue. The scanty flow of saliva may reduce the effectiveness of cleansing, buffering and lubrication mechanisms as well as resulting in a marked reduction in the total amount of specific and non-specific immune factors entering the mouth.

  1. T1-weighted MRI for the detection of coronary artery plaque haemorrhage

    International Nuclear Information System (INIS)

    Oei, May Lin; Ozgun, Murat; Seifarth, Harald; Bunck, Alexander; Fischbach, Roman; Heindel, Walter; Maintz, David; Orwat, Stefan; Botnar, Rene

    2010-01-01

    Hyperintense areas in atherosclerotic plaques on pre-contrast T1-weighted MRI have been shown to correlate with intraplaque haemorrhage. We evaluated the presence of T1 hyperintensity in coronary artery plaques in coronary artery disease (CAD) patients and correlated results with multi-detector computed tomography (MDCT) findings. Fifteen patients with CAD were included. Plaques detected by MDCT were categorised based on their Hounsfield number. T1-weighted inversion recovery (IR) MRI prepared coronary MRI for the detection of plaque and steady-state free-precession coronary MR-angiography for anatomical correlation was performed. After registration of MDCT and MRI, regions of interest were defined on MDCT-visible plaques and in corresponding vessel segments acquired with MRI. MDCT density and MR signal measurement were performed in each plaque. Forty-three plaques were identified with MDCT. With IR-MRI 5/43 (12%) plaques were hyperintense, 2 of which were non-calcified and 3 mixed. Average signal-to-noise and contrast-to-noise ratios of hyperintense plaques were 15.7 and 9.1, compared with 5.6 and 1.2 for hypointense plaques. Hyperintense plaques exhibited a significantly lower CT density than hypointense plaques (63.6 vs. 140.8). There was no correlation of plaque signal intensity with degree of stenosis. T1-weighted IR-MRI may be useful for non-invasive detection and characterisation of intraplaque haemorrhage in coronary artery plaques. (orig.)

  2. Auditory brainstem responses of CBA/J mice with neonatal conductive hearing losses and treatment with GM1 ganglioside.

    Science.gov (United States)

    Money, M K; Pippin, G W; Weaver, K E; Kirsch, J P; Webster, D B

    1995-07-01

    Exogenous administration of GM1 ganglioside to CBA/J mice with a neonatal conductive hearing loss ameliorates the atrophy of spiral ganglion neurons, ventral cochlear nucleus neurons, and ventral cochlear nucleus volume. The present investigation demonstrates the extent of a conductive loss caused by atresia and tests the hypothesis that GM1 ganglioside treatment will ameliorate the conductive hearing loss. Auditory brainstem responses were recorded from four groups of seven mice each: two groups received daily subcutaneous injections of saline (one group had normal hearing; the other had a conductive hearing loss); the other two groups received daily subcutaneous injections of GM1 ganglioside (one group had normal hearing; the other had a conductive hearing loss). In mice with a conductive loss, decreases in hearing sensitivity were greatest at high frequencies. The decreases were determined by comparing mean ABR thresholds of the conductive loss mice with those of normal hearing mice. The conductive hearing loss induced in the mice in this study was similar to that seen in humans with congenital aural atresias. GM1 ganglioside treatment had no significant effect on ABR wave I thresholds or latencies in either group.

  3. MRI of the transplanted endothelial progenitor cells for prevent atherosclerotic plaque formation

    International Nuclear Information System (INIS)

    Ma Zhanlong; Teng Gaojun; Mai Xiaoli; Chen Jun; Sun Junhui; Zhang Hongying; Yu Hui; Li Guozhao

    2007-01-01

    Objective: To evaluate the 1.5 T magnetic resonance imaging system to depict and track in vivo of magnetically labeled endothelial progenitor cells (EPCs), and to study the possibility for preventing the atherosclerotic plaque formation in New Zealand rabbit model of carotid arterial injury after transplantation. Methods: New Zealand rabbit EPCs were isolated, confirmed, expanded and then incubated with home synthesized Fe 2 O 3 -PLL, Prussian blue stain was performed for showing intracellular irons. The model of carotid arterial injury was performed by 2.5F balloons, the group A of 8 rabbits received magnetically labeled EPCs, group B of 3 rabbits received fluorescent-labeled EPCs and the group C of 5 rabbits were given same volume saline injection after endothelial injury of the carotid artery. MR imaging and histology were performed and compared 4 days later for randomly chosen three rabbit, each from one of the three group; all the other rabbits were fed with high lipid diet and examed using MR imaging and histology after 15 weeks. Results: Epcs labeling efficiency was more than 95% by Prussian blue stain, 4 days after transplantation of EPCs, only in group A, the injured endothelium of carotid artery had signal intensity loss in T 2 * WI, which were correlated well with the area where the most Prussian blue staining positive cells were found in histopathology analyses. The rabbits of group A and B which received EPCs transplantation exhibited fewer plaques formation than those of the group C (P 2 O 3 -PLL. The 1.5 T magnetic resonance imaging system could depict and monitor the magnetically labeled endothelial progenitor cells homing to the injured endothelium of the artery, and EPCs contribute to preventing atherosclerotic plaque formation in New Zealand rabbit model of atherosclerosis. (authors)

  4. Radiation regression patterns after cobalt plaque insertion for retinoblastoma

    International Nuclear Information System (INIS)

    Buys, R.J.; Abramson, D.H.; Ellsworth, R.M.; Haik, B.

    1983-01-01

    An analysis of 31 eyes of 30 patients who had been treated with cobalt plaques for retinoblastoma disclosed that a type I radiation regression pattern developed in 15 patients; type II, in one patient, and type III, in five patients. Nine patients had a regression pattern characterized by complete destruction of the tumor, the surrounding choroid, and all of the vessels in the area into which the plaque was inserted. This resulting white scar, corresponding to the sclerae only, was classified as a type IV radiation regression pattern. There was no evidence of tumor recurrence in patients with type IV regression patterns, with an average follow-up of 6.5 years, after receiving cobalt plaque therapy. Twenty-nine of these 30 patients had been unsuccessfully treated with at least one other modality (ie, light coagulation, cryotherapy, external beam radiation, or chemotherapy)

  5. Radiation regression patterns after cobalt plaque insertion for retinoblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Buys, R.J.; Abramson, D.H.; Ellsworth, R.M.; Haik, B.

    1983-08-01

    An analysis of 31 eyes of 30 patients who had been treated with cobalt plaques for retinoblastoma disclosed that a type I radiation regression pattern developed in 15 patients; type II, in one patient, and type III, in five patients. Nine patients had a regression pattern characterized by complete destruction of the tumor, the surrounding choroid, and all of the vessels in the area into which the plaque was inserted. This resulting white scar, corresponding to the sclerae only, was classified as a type IV radiation regression pattern. There was no evidence of tumor recurrence in patients with type IV regression patterns, with an average follow-up of 6.5 years, after receiving cobalt plaque therapy. Twenty-nine of these 30 patients had been unsuccessfully treated with at least one other modality (ie, light coagulation, cryotherapy, external beam radiation, or chemotherapy).

  6. Dosimetric study of the 15 mm ROPES eye plaque

    International Nuclear Information System (INIS)

    Granero, D.; Perez-Calatayud, J.; Ballester, F.; Casal, E.; Frutos, J.M. de

    2004-01-01

    The main aim of this paper is to make a study of dose-rate distributions obtained around the 15 mm, radiation oncology physics and engineering services, Australia (ROPES) eye plaque loaded with 125 I model 6711 radioactive seeds. In this study, we have carried out a comparison of the dose-rate distributions obtained by the algorithm used by the Plaque Simulator (PS) (BEBIG GmbH, Berlin, Germany) treatment planning system with those obtained by means of the Monte Carlo method for the ROPES eye plaque. A simple method to obtain the dose-rate distributions in a treatment planning system via the superposition of the dose-rate distributions of a seed placed in the eye plaque has been developed. The method uses eye plaque located in a simplified geometry of the head anatomy and distributions obtained by means of the Monte Carlo code GEANT4. The favorable results obtained in the development of this method suggest that it could be implemented on a treatment planning system to improve dose-rate calculations. We have also found that the dose-rate falls sharply along the eye and that outside the eye the dose-rate is very low. Furthermore, the lack of backscatter photons from the air located outside the eye-head phantom produces a dose reduction negligible for distances from the eye-plaque r<1 cm but reaches up to 20% near the air-eye interface. Results showed that the treatment planning system lacks accuracy around the border of the eye (in the sclera and the surrounding area) due to the simplicity of the algorithm used. The BEBIG treatment planning system uses a global attenuation factor that takes into account the effect of the eye plaque seed carrier and the lack of backscatter photons caused by the metallic cover, which in the case of a ROPES eye plaque has a default value of T=1 (no correction). In the present study, a global attenuation factor T=0.96 and an air-interface correction factor which improve on treatment planning system calculations were obtained

  7. Dosimetry on ocular brachytherapy with I-125 ophthalmologic ROPES and COMS plaques

    Energy Technology Data Exchange (ETDEWEB)

    Mourao, Arnaldo P. [Centro Federal de Educacao Tecnoloica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil). Nucleo de Engenharia Hospitalar], e-mail: aprata@des.cefetmg.br; Campos, Tarcisio P.R. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Programa de Pos-graduacao em Ciencias e Tecnicas Nucleares], e-mail: campos@nuclear.ufmg.br

    2009-07-01

    Radiotherapy is an alternative to ocular enucleation. However, the irradiation of ocular region can bring deleterious effects due to the high doses, mainly in the lens, retina and in the bone structures in growth phase. Brachytherapy instead of teletherapy looks for departuring absorbed doses in tumor minimizing doses in the lens and the adjacent tissues of the eyeball (orbital region), avoiding deleterious effects. Thus, a three-dimensional computational voxel model and an analytical model were coupled, including the heterogeneous properties of the globe and the adjacent tissues. The analytical model was applied to define the thin structures of the ocular globe. This computational model is used to simulate orbital irradiation with ROPES and COMS ophthalmologic plaques placed on the sclera surface filled to ten and eight iodine-125 seeds, respectively. Simulations are performed on the MCNP5 code. The computational simulation allows evaluating how the dose rates are spatially distributed in the orbital volume. The results are normalized to 100% at the maximum dose on the tumor base, and by the applied source activity. The external globe structures receive 0.5% of the maximum internal dose. The crystalline lens dosimetry depends on the position and thickness of the tumor and the plaque diameters. On the present case, 12.75% of maximum dose is found on the lens. The maximum dose is found onto the eyeball, in the vitreous. The present model represents an advance in simulating and predicting absorbed dose on ocular brachytherapy, incorporating anthropomorphic and anthropometric features of the real eyeball. (author)

  8. Dosimetry on ocular brachytherapy with I-125 ophthalmologic ROPES and COMS plaques

    International Nuclear Information System (INIS)

    Mourao, Arnaldo P.; Campos, Tarcisio P.R.

    2009-01-01

    Radiotherapy is an alternative to ocular enucleation. However, the irradiation of ocular region can bring deleterious effects due to the high doses, mainly in the lens, retina and in the bone structures in growth phase. Brachytherapy instead of teletherapy looks for departuring absorbed doses in tumor minimizing doses in the lens and the adjacent tissues of the eyeball (orbital region), avoiding deleterious effects. Thus, a three-dimensional computational voxel model and an analytical model were coupled, including the heterogeneous properties of the globe and the adjacent tissues. The analytical model was applied to define the thin structures of the ocular globe. This computational model is used to simulate orbital irradiation with ROPES and COMS ophthalmologic plaques placed on the sclera surface filled to ten and eight iodine-125 seeds, respectively. Simulations are performed on the MCNP5 code. The computational simulation allows evaluating how the dose rates are spatially distributed in the orbital volume. The results are normalized to 100% at the maximum dose on the tumor base, and by the applied source activity. The external globe structures receive 0.5% of the maximum internal dose. The crystalline lens dosimetry depends on the position and thickness of the tumor and the plaque diameters. On the present case, 12.75% of maximum dose is found on the lens. The maximum dose is found onto the eyeball, in the vitreous. The present model represents an advance in simulating and predicting absorbed dose on ocular brachytherapy, incorporating anthropomorphic and anthropometric features of the real eyeball. (author)

  9. Early supra- and subgingival plaque formation in experimental gingivitis in smokers and never-smokers.

    Science.gov (United States)

    Branco, Paula; Weidlich, Patricia; Oppermann, Rui Vicente; Rösing, Cassiano Kuchenbecker

    2015-01-01

    To evaluate supragingival and subgingival plaque formation on the dentogingival area in smokers and never smokers using the experimental gingivitis model and a plaque scoring system that considers the presence of an area free of plaque between plaque and the gingival sulcus called the plaque free zone (PFZ). Male volunteers, 9 current smokers and 10 never-smokers, refrained from oral hygiene procedures in the maxillary incisors and canines (test teeth) for 25 days. Under conditions of clinically healthy gingiva (phase 1) and gingival inflammation (phase 2), the supragingival plaque formation pattern was observed for 4 days in the dentogingival area. Gingival crevicular fluid was also measured. Plaque was dyed with fucsine and its presence was recorded by a calibrated examiner based on a 3-criteria scoring system: 0 - absence of stained plaque; 1 - presence of stained plaque and supragingival PFZ; 2 - presence of stained plaque and absence of PFZ, indicating that subgingival plaque formation has taken place. In both phases, smokers presented a significantly lower relative frequency of sites with subgingival plaque compared to never-smokers (P smokers demonstrated a significantly lower frequency of gingival bleeding than did non-smokers (23.6% vs 66.1%; P Smokers presented significantly lower percentages of sites with subgingival plaque in all experimental periods and presented less gingival inflammation as shown by GBI and gingival crevicular fluid quantification.

  10. Characterization of plaque in the internal carotid artery. Comparison neuroradiological findings with pathological findings

    International Nuclear Information System (INIS)

    Nishikawa, Misao; Nishio, Akimasa; Takami, Toshihiro; Goto, Takeo; Ueda, Makiko; Hara, Mitsuhiro

    2006-01-01

    We evaluate the morphology of the carotid plaque using echogram, CT scan and MRI and compare those neuroradiological findings with histological findings of the plaque. We evaluated 14 cases operated with carotid endoarterectomy for carotid stenosis. We estimated the findings of the echogram, enhanced CT scan and black blood MRI (BB MRI), in comparison with the histological findings of the carotid plaque. Echogram, enhanced CT scan and MRI clearly demonstrated the plaque in cervical carotid stenosis. In most cases, echograms could show the plaque, but in some cases could not due to the back shadow caused by plaque calcification. Enhanced CT scan clearly demonstrated the calcification and the neovasculization in plaque. BB MRI clearly showed the carotid plaque. Low-intensity lesions in T1 and T2 weighted images showed hard and fibrous plaque. High-intensity lesions in T1 and T2 weighted images showed soft plaque with lipoprotein and/or hemorrhage. This study demonstrates the potential of a systemic approach to atherosclerotic plaque with enhanced CT scan and BB MRI compared with histological findings of the carotid plaque. These estimations elucidate the growth mechanism of carotid plaque. (author)

  11. Regional Fluid-Attenuated Inversion Recovery (FLAIR at 7 Tesla correlates with Amyloid beta in Hippocampus and Brainstem of cognitively normal elderly subjects.

    Directory of Open Access Journals (Sweden)

    Simon J Schreiner

    2014-09-01

    Full Text Available Background: Accumulation of amyloid beta (Aβ may occur during healthy aging and is a risk factor for Alzheimer Disease (AD. While individual Aβ-accumulation can be measured non-invasively using Pittsburgh compound-B positron-emission-tomography (PiB-PET, Fluid-Attenuated Inversion Recovery (FLAIR is a Magnetic Resonance Imaging (MRI sequence, capable of indicating heterogeneous age-related brain pathologies associated with tissue-edema. In the current study cognitively normal elderly subjects were investigated for regional correlation of PiB- and FLAIR- intensity. Methods: 14 healthy elderly subjects without known history of cognitive impairment received 11C-PiB-PET for estimation of regional Aβ-load. In addition, whole brain T1-MPRAGE and FLAIR-MRI sequences were acquired at high field strength of 7 Tesla (7T. Volume-normalized intensities of brain regions were assessed by applying an automated subcortical segmentation algorithm for spatial definition of brain structures. Statistical dependence between FLAIR- and PiB-PET intensities was tested using Spearman's rank correlation coefficient (rho, followed by Holm-Bonferroni correction for multiple testing. Results: Neuropsychological testing revealed normal cognitive performance levels in all participants. Mean regional PiB-PET and FLAIR intensities were normally distributed and independent. Significant correlation between volume-normalized PiB-PET signals and FLAIR intensities resulted for Hippocampus (right:rho=0.86; left:rho=0.84, Brainstem (rho=0.85 and left Basal Ganglia vessel region (rho=0.82. Conclusions: Our finding of a significant relationship between PiB- and FLAIR-intensity mainly observable in the Hippocampus and Brainstem, indicates regional Aβ associated tissue-edema in cognitively normal elderly subjects. Further studies including clinical populations are necessary to clarify the relevance of our findings for estimating individual risk for age-related neurodegenerative

  12. Regional Fluid-Attenuated Inversion Recovery (FLAIR) at 7 Tesla correlates with amyloid beta in hippocampus and brainstem of cognitively normal elderly subjects

    Science.gov (United States)

    Schreiner, Simon J.; Liu, Xinyang; Gietl, Anton F.; Wyss, Michael; Steininger, Stefanie C.; Gruber, Esmeralda; Treyer, Valerie; Meier, Irene B.; Kälin, Andrea M.; Leh, Sandra E.; Buck, Alfred; Nitsch, Roger M.; Pruessmann, Klaas P.; Hock, Christoph; Unschuld, Paul G.

    2014-01-01

    Background: Accumulation of amyloid beta (Aβ) may occur during healthy aging and is a risk factor for Alzheimer Disease (AD). While individual Aβ-accumulation can be measured non-invasively using Pittsburgh Compund-B positron emission tomography (PiB-PET), Fluid-attenuated inversion recovery (FLAIR) is a Magnetic Resonance Imaging (MRI) sequence, capable of indicating heterogeneous age-related brain pathologies associated with tissue-edema. In the current study cognitively normal elderly subjects were investigated for regional correlation of PiB- and FLAIR intensity. Methods: Fourteen healthy elderly subjects without known history of cognitive impairment received 11C-PiB-PET for estimation of regional Aβ-load. In addition, whole brain T1-MPRAGE and FLAIR-MRI sequences were acquired at high field strength of 7 Tesla (7T). Volume-normalized intensities of brain regions were assessed by applying an automated subcortical segmentation algorithm for spatial definition of brain structures. Statistical dependence between FLAIR- and PiB-PET intensities was tested using Spearman's rank correlation coefficient (rho), followed by Holm–Bonferroni correction for multiple testing. Results: Neuropsychological testing revealed normal cognitive performance levels in all participants. Mean regional PiB-PET and FLAIR intensities were normally distributed and independent. Significant correlation between volume-normalized PiB-PET signals and FLAIR intensities resulted for Hippocampus (right: rho = 0.86; left: rho = 0.84), Brainstem (rho = 0.85) and left Basal Ganglia vessel region (rho = 0.82). Conclusions: Our finding of a significant relationship between PiB- and FLAIR intensity mainly observable in the Hippocampus and Brainstem, indicates regional Aβ associated tissue-edema in cognitively normal elderly subjects. Further studies including clinical populations are necessary to clarify the relevance of our findings for estimating individual risk for age-related neurodegenerative

  13. Neurodegenerative changes in the brainstem and olfactory bulb in people older than 50 years old: a descriptive study

    Directory of Open Access Journals (Sweden)

    Francine Hehn de Oliveira

    2015-07-01

    Full Text Available With the increase in life expectancy in Brazil, concerns have grown about the most prevalent diseases in elderly people. Among these diseases are neurodegenerative diseases, such as Alzheimer’s and Parkinson’s diseases. Protein deposits related to the development of these diseases can pre-date the symptomatic phases by years. The tau protein is particularly interesting: it might be found in the brainstem and olfactory bulb long before it reaches the limbic cortex, at which point symptoms occur. Of the 14 brains collected in this study, the tau protein was found in the brainstems of 10 (71.42% and in olfactory bulbs of 3 out 11. Of the 7 individuals who had a final diagnosis of Alzheimer’s disease (AD, 6 presented tau deposits in some region of the brainstem. Our data support the idea of the presence of tau protein in the brainstem and olfactory bulb in the earliest stages of AD.

  14. An assessment of the vulnerability of carotid plaques: a comparative study between intraplaque neovascularization and plaque echogenicity

    International Nuclear Information System (INIS)

    Zhou, Yangyang; Li, Yan; Bai, Yang; Chen, Ying; Sun, Xiaofeng; Zhu, Yingqiao; Wu, Jiang

    2013-01-01

    Carotid plaque echolucency as detected by Color Doppler ultrasonography (CDUS) has been used as a potential marker of plaque vulnerability. However, contrast-enhanced ultrasound (CEUS) has recently been shown to be a valuable method to evaluate the vulnerability and neovascularization within carotid atherosclerotic plaques. The aim of this study was to compare CEUS and CDUS in the assessment of plaque vulnerability using transcranial color Doppler (TCD) monitoring of microembolic signals (MES) as a reference technique. A total of 46 subjects with arterial stenosis (≥ 50%) underwent a carotid duplex ultrasound, TCD monitoring of MES and CEUS (SonoVue doses of 2.0 mL) within a span of 3 days. The agreement between the CEUS, CDUS, and MES findings was assessed with a chi-square test. A p-value less than 0.05 was considered statistically significant. Neovascularization was observed in 30 lesions (44.4%). The vascular risk factors for stroke were similar and there were no age or gender differences between the 2 groups. Using CEUS, MES were identified in 2 patients (12.5%) within class 1 (non-neovascularization) as opposed to 15 patients (50.0%) within class 2 (neovascularization) (p = 0.023). CDUS revealed no significant differences in the appearance of the MES between the 2 groups (hyperechoic and hypoechoic) (p = 0.237). This study provides preliminary evidence to suggest that intraplaque neovascularization detected by CEUS is associated with the presence of MESs, where as plaque echogenicity on traditional CDUS does not. These findings argue that CEUS may better identify high-risk plaques

  15. Effects of extracellular plaque components on the chlorhexidine sensitivity of strains of Streptococcus mutans and human dental plaque

    International Nuclear Information System (INIS)

    Wolinsky, L.E.; Hume, W.R.

    1985-01-01

    An in vitro study was undertaken to determine the effects of sucrose-derived extracellular plaque components on the sensitivity of selected oral bacteria to chlorhexidine (CX). Cultures of Streptococcus mutans HS-6, OMZ-176, Ingbritt C, 6715-wt13, and pooled human plaque were grown in trypticase soy media with or without 1% sucrose. The sensitivity to CX of bacteria grown in each medium was determined by fixed-time exposure to CX and subsequent measurement of 3 H-thymidine uptake. One-hour exposure to CX at concentrations of 10(-4) M (0.01% w/v) or greater substantially inhibited subsequent cellular division among all the S. mutans strains and human plaque samples tested. An IC50 (the CX concentration which depressed 3 H-thymidine incorporation to 50% of control level) of close to 10(-4) M was noted for S. mutans strains HS-6, OMZ-176, and 6715-wt13 when grown in the presence of sucrose. The same strains grown in cultures without added sucrose showed about a ten-fold greater sensitivity to CX (IC50 close to 10(-5) M). A three-fold difference was noted for S. mutans Ingbritt C. Only a slight increase in the IC50 was noted for the plaque samples cultured in sucrose-containing media, but their threshold for depression of 3 H-thymidine uptake by CX was lower than that for the sucrose-free plaque samples. The study showed that extracellular products confer some protection against CX to the bacteria examined, and provided an explanation for the disparity between clinically-recommended concentrations for plaque suppression and data on in vitro susceptibility

  16. Abnormal Auditory Brainstem Response (ABR Findings in a Near-Normal Hearing Child with Noonan Syndrome

    Directory of Open Access Journals (Sweden)

    Bahram Jalaei

    2017-01-01

    Full Text Available Introduction: Noonan syndrome (NS is a heterogeneous genetic disease that affects many parts of the body. It was named after Dr. Jacqueline Anne Noonan, a paediatric cardiologist.Case Report: We report audiological tests and auditory brainstem response (ABR findings in a 5-year old Malay boy with NS. Despite showing the marked signs of NS, the child could only produce a few meaningful words. Audiological tests found him to have bilateral mild conductive hearing loss at low frequencies. In ABR testing, despite having good waveform morphology, the results were atypical. Absolute latency of wave V was normal but interpeak latencies of wave’s I-V, I-II, II-III were prolonged. Interestingly, interpeak latency of waves III-V was abnormally shorter.Conclusion:Abnormal ABR results are possibly due to abnormal anatomical condition of brainstem and might contribute to speech delay.

  17. Effect of Infant Prematurity on Auditory Brainstem Response at Preschool Age

    Directory of Open Access Journals (Sweden)

    Sara Hasani

    2013-03-01

    Full Text Available Introduction: Preterm birth is a risk factor for a number of conditions that requires comprehensive examination. Our study was designed to investigate the impact of preterm birth on the processing of auditory stimuli and brain structures at the brainstem level at a preschool age.   Materials and Methods: An auditory brainstem response (ABR test was performed with low rates of stimuli in 60 children aged 4 to 6 years. Thirty subjects had been born following a very preterm labor or late-preterm labor and 30 control subjects had been born following a full-term labor.   Results: Significant differences in the ABR test result were observed in terms of the inter-peak intervals of the I–III and III–V waves, and the absolute latency of the III wave (P

  18. Sequential change in MRI in two cases with small brainstem infarctions

    International Nuclear Information System (INIS)

    Masuda, Ryoichi; Fukuda, Osamu; Endoh, Shunro; Takaku, Akira; Suzuki, Takashi; Satoh, Shuji

    1987-01-01

    Magnetic resonance imaging (MRI) has been found to be very useful for the diagnosis of a small brainstem infarction. However, most reported cases have shown the changes at only the chronic stage. In this report, sequential changes in the MRI in two cases with small brainstem infarctions are presented. In Case 1, a 67-year-old man with a pure sensory stroke on the right side, a small infarcted area was observed at the left medial side of the pontomedullary junction on MRI. In Case 2, a 62-year-old man with a pure motor hemiparesis of the left side, MRI revealed a small infarcted area on the right ventral of the middle pons. The initial changes were confirmed 5 days (Case 1) and 18 hours (Case 2) after the onset of the completed stroke. No abnormal findings could be found in the computed tomography in either case. (author)

  19. Hypertensive brainstem encephalopathy involving deep supratentorial regions: does only blood pressure matter?

    Directory of Open Access Journals (Sweden)

    Jong-Ho Park

    2010-04-01

    Full Text Available We report on a 42-year-old female patient who presented with high arterial blood pressure of 245/150 mmHg and hypertensive brainstem encephalopathy that involved the brainstem and extensive supratentorial deep gray and white matter. The lesions were nearly completely resolved several days after stabilization of the arterial blood pressure. Normal diffusion-weighted imaging findings and high apparent diffusion coefficient values suggested that the main pathomechanism was vasogenic edema owing to severe hypertension. On the basis of a literature review, the absolute value of blood pressure or whether the patient can control his/her blood pressure seems not to be associated with the degree of the lesions evident on magnetic resonance imaging. It remains to be determined if the acceleration rate and the duration of elevated arterial blood pressure might play a key role in the development of the hypertensive encephalopathy pattern.

  20. SU-E-T-443: Geometric Uncertainties in Eye Plaque Dosimetry for a Fully Loaded 16 Mm COMS Plaque

    International Nuclear Information System (INIS)

    Morrison, H; Menon, G; Jans, H; Larocque, M; Sloboda, R

    2015-01-01

    Purpose: To determine the effect of geometric uncertainties in the seed positions in a COMS eye plaque on the central axis (CAX) dose. Methods: A Silastic insert was placed into a photopolymer 3D printed 16 mm COMS plaque, which was then positioned onto a custom-designed PMMA eye phantom. High resolution 3D images were acquired of the setup using a Siemens Inveon microPET/CT scanner. Images were acquired with the plaque unloaded and loaded with IsoAid I-125 seed shells (lack of silver core to minimize metal artifacts). Seed positions and Silastic thickness beneath each slot were measured. The measured seed coordinates were used to alter the seed positions within a standard 16 mm COMS plaque in Plaque Simulator v5.7.3 software. Doses along the plaque CAX were compared for the original and modified plaque coordinates using 3.5 mCi seeds with treatment times set to deliver 70 Gy to tumour apexes of 3.5, 5, and 10 mm height. Results: The majority of seeds showed length-wise displacement, and all seeds showed displacement radially outward from the eye center. The average radial displacement was 0.15 mm larger than the expected 1.4 mm offset, approximately half of which was due to increased Silastic thickness beneath each slot. The CAX doses for the modified seed positions were consistently lower for all tumour heights due to geometric displacement of the seeds; dose differences were found to increase to a maximum of 2.6% at a depth of ∼10 mm, after which they decreased due to the inverse square dose fall-off minimizing this effect. Conclusion: This work presents initial results of a broader dosimetric uncertainty evaluation for fully loaded COMS eye plaques and demonstrates the effects of seed positioning uncertainties. The small shifts in seed depths had noticeable effects on the CAX doses indicating the importance of careful Silastic loading. Funding provided by Alberta Cancer Foundation Grant #26655, Vanier Canada Graduate Scholarship, and Alberta Innovates Health

  1. Modeling Parkinson’s Disease Falls Associated With Brainstem Cholinergic Systems Decline

    OpenAIRE

    Kucinski, Aaron; Sarter, Martin

    2015-01-01

    In addition to the primary disease-defining symptoms, approximately half of patients with Parkinson’s disease (PD) suffer from postural instability, impairments in gait control and a propensity for falls. Consistent with evidence from patients, we previously demonstrated that combined striatal dopamine (DA) and basal forebrain (BF) cholinergic cell loss causes falls in rats traversing dynamic surfaces. Because evidence suggests that degeneration of brainstem cholinergic neurons arising from t...

  2. Brainstem encoding of speech and musical stimuli in congenital amusia: Evidence from Cantonese speakers

    Directory of Open Access Journals (Sweden)

    Fang eLiu

    2015-01-01

    Full Text Available Congenital amusia is a neurodevelopmental disorder of musical processing that also impacts subtle aspects of speech processing. It remains debated at what stage(s of auditory processing deficits in amusia arise. In this study, we investigated whether amusia originates from impaired subcortical encoding of speech (in quiet and noise and musical sounds in the brainstem. Fourteen Cantonese-speaking amusics and 14 matched controls passively listened to six Cantonese lexical tones in quiet, two Cantonese tones in noise (signal-to-noise ratios at 0 and 20 dB, and two cello tones in quiet while their frequency-following responses (FFRs to these tones were recorded. All participants also completed a behavioral lexical tone identification task. The results indicated normal brainstem encoding of pitch in speech (in quiet and noise and musical stimuli in amusics relative to controls, as measured by FFR pitch strength, pitch error, and stimulus-to-response correlation. There was also no group difference in neural conduction time or FFR amplitudes. Both groups demonstrated better FFRs to speech (in quiet and noise than to musical stimuli. However, a significant group difference was observed for tone identification, with amusics showing significantly lower accuracy than controls. Analysis of the tone confusion matrices suggested that amusics were more likely than controls to confuse between tones that shared similar acoustic features. Interestingly, this deficit in lexical tone identification was not coupled with brainstem abnormality for either speech or musical stimuli. Together, our results suggest that the amusic brainstem is not functioning abnormally, although higher-order linguistic pitch processing is impaired in amusia. This finding has significant implications for theories of central auditory processing, requiring further investigations into how different stages of auditory processing interact in the human brain.

  3. Brainstem encoding of speech and musical stimuli in congenital amusia: evidence from Cantonese speakers.

    Science.gov (United States)

    Liu, Fang; Maggu, Akshay R; Lau, Joseph C Y; Wong, Patrick C M

    2014-01-01

    Congenital amusia is a neurodevelopmental disorder of musical processing that also impacts subtle aspects of speech processing. It remains debated at what stage(s) of auditory processing deficits in amusia arise. In this study, we investigated whether amusia originates from impaired subcortical encoding of speech (in quiet and noise) and musical sounds in the brainstem. Fourteen Cantonese-speaking amusics and 14 matched controls passively listened to six Cantonese lexical tones in quiet, two Cantonese tones in noise (signal-to-noise ratios at 0 and 20 dB), and two cello tones in quiet while their frequency-following responses (FFRs) to these tones were recorded. All participants also completed a behavioral lexical tone identification task. The results indicated normal brainstem encoding of pitch in speech (in quiet and noise) and musical stimuli in amusics relative to controls, as measured by FFR pitch strength, pitch error, and stimulus-to-response correlation. There was also no group difference in neural conduction time or FFR amplitudes. Both groups demonstrated better FFRs to speech (in quiet and noise) than to musical stimuli. However, a significant group difference was observed for tone identification, with amusics showing significantly lower accuracy than controls. Analysis of the tone confusion matrices suggested that amusics were more likely than controls to confuse between tones that shared similar acoustic features. Interestingly, this deficit in lexical tone identification was not coupled with brainstem abnormality for either speech or musical stimuli. Together, our results suggest that the amusic brainstem is not functioning abnormally, although higher-order linguistic pitch processing is impaired in amusia. This finding has significant implications for theories of central auditory processing, requiring further investigations into how different stages of auditory processing interact in the human brain.

  4. Brainstem encoding of speech and musical stimuli in congenital amusia: evidence from Cantonese speakers

    Science.gov (United States)

    Liu, Fang; Maggu, Akshay R.; Lau, Joseph C. Y.; Wong, Patrick C. M.

    2015-01-01

    Congenital amusia is a neurodevelopmental disorder of musical processing that also impacts subtle aspects of speech processing. It remains debated at what stage(s) of auditory processing deficits in amusia arise. In this study, we investigated whether amusia originates from impaired subcortical encoding of speech (in quiet and noise) and musical sounds in the brainstem. Fourteen Cantonese-speaking amusics and 14 matched controls passively listened to six Cantonese lexical tones in quiet, two Cantonese tones in noise (signal-to-noise ratios at 0 and 20 dB), and two cello tones in quiet while their frequency-following responses (FFRs) to these tones were recorded. All participants also completed a behavioral lexical tone identification task. The results indicated normal brainstem encoding of pitch in speech (in quiet and noise) and musical stimuli in amusics relative to controls, as measured by FFR pitch strength, pitch error, and stimulus-to-response correlation. There was also no group difference in neural conduction time or FFR amplitudes. Both groups demonstrated better FFRs to speech (in quiet and noise) than to musical stimuli. However, a significant group difference was observed for tone identification, with amusics showing significantly lower accuracy than controls. Analysis of the tone confusion matrices suggested that amusics were more likely than controls to confuse between tones that shared similar acoustic features. Interestingly, this deficit in lexical tone identification was not coupled with brainstem abnormality for either speech or musical stimuli. Together, our results suggest that the amusic brainstem is not functioning abnormally, although higher-order linguistic pitch processing is impaired in amusia. This finding has significant implications for theories of central auditory processing, requiring further investigations into how different stages of auditory processing interact in the human brain. PMID:25646077

  5. Neurochemical dynamics of acute orofacial pain in the human trigeminal brainstem nuclear complex.

    Science.gov (United States)

    de Matos, Nuno M P; Hock, Andreas; Wyss, Michael; Ettlin, Dominik A; Brügger, Mike

    2017-11-15

    The trigeminal brainstem sensory nuclear complex is the first central relay structure mediating orofacial somatosensory and nociceptive perception. Animal studies suggest a substantial involvement of neurochemical alterations at such basal CNS levels in acute and chronic pain processing. Translating this animal based knowledge to humans is challenging. Human related examining of brainstem functions are challenged by MR related peculiarities as well as applicability aspects of experimentally standardized paradigms. Based on our experience with an MR compatible human orofacial pain model, the aims of the present study were twofold: 1) from a technical perspective, the evaluation of proton magnetic resonance spectroscopy at 3 T regarding measurement accuracy of neurochemical profiles in this small brainstem nuclear complex and 2) the examination of possible neurochemical alterations induced by an experimental orofacial pain model. Data from 13 healthy volunteers aged 19-46 years were analyzed and revealed high quality spectra with significant reductions in total N-acetylaspartate (N-acetylaspartate + N-acetylaspartylglutamate) (-3.7%, p = 0.009) and GABA (-10.88%, p = 0.041) during the pain condition. These results might reflect contributions of N-acetylaspartate and N-acetylaspartylglutamate in neuronal activity-dependent physiologic processes and/or excitatory neurotransmission, whereas changes in GABA might indicate towards a reduction in tonic GABAergic functioning during nociceptive signaling. Summarized, the present study indicates the applicability of 1 H-MRS to obtain neurochemical dynamics within the human trigeminal brainstem sensory nuclear complex. Further developments are needed to pave the way towards bridging important animal based knowledge with human research to understand the neurochemistry of orofacial nociception and pain. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Limbic encephalitis with antibodies to glutamic acid decarboxylase presenting with brainstem symptoms

    Directory of Open Access Journals (Sweden)

    Faruk Incecik

    2015-01-01

    Full Text Available Limbic encephalitis (LE is a neurological syndrome that may present in association with cancer, infection, or as an isolate clinical condition often accompanying autoimmune disorders. LE associated with glutamic acid decarboxylase antibodies (anti-GAD is rare in children. Here, we characterized the clinical and laboratory features of a patient presenting with brainstem involvement with non-paraneoplastic LE associated with anti-GAD antibodies. In our patient, after plasma exchange, we determined a dramatic improvement of the neurological deficits.

  7. Somatotopic Arrangement and Location of the Corticospinal Tract in the Brainstem of the Human Brain

    OpenAIRE

    Jang, Sung Ho

    2011-01-01

    The corticospinal tract (CST) is the most important motor pathway in the human brain. Detailed knowledge of CST somatotopy is important in terms of rehabilitative management and invasive procedures for patients with brain injuries. In this study, I conducted a review of nine previous studies of the somatotopical location and arrangement at the brainstem in the human brain. The results of this review indicated that the hand and leg somatotopies of the CST are arranged medio-laterally in the mi...

  8. Retrospective analysis of 104 histologically proven adult brainstem gliomas: clinical symptoms, therapeutic approaches and prognostic factors

    International Nuclear Information System (INIS)

    Reithmeier, Thomas; Kuzeawu, Aanyo; Hentschel, Bettina; Loeffler, Markus; Trippel, Michael; Nikkhah, Guido

    2014-01-01

    Adult brainstem gliomas are rare primary brain tumors (<2% of gliomas). The goal of this study was to analyze clinical, prognostic and therapeutic factors in a large series of histologically proven brainstem gliomas. Between 1997 and 2007, 104 patients with a histologically proven brainstem glioma were retrospectively analyzed. Data about clinical course of disease, neuropathological findings and therapeutic approaches were analyzed. The median age at diagnosis was 41 years (range 18-89 years), median KPS before any operative procedure was 80 (range 20-100) and median survival for the whole cohort was 18.8 months. Histopathological examinations revealed 16 grade I, 31 grade II, 42 grade III and 14 grade IV gliomas. Grading was not possible in 1 patient. Therapeutic concepts differed according to the histopathology of the disease. Median overall survival for grade II tumors was 26.4 months, for grade III tumors 12.9 months and for grade IV tumors 9.8 months. On multivariate analysis the relative risk to die increased with a KPS ≤ 70 by factor 6.7, with grade III/IV gliomas by the factor 1.8 and for age ≥ 40 by the factor 1.7. External beam radiation reduced the risk to die by factor 0.4. Adult brainstem gliomas present with a wide variety of neurological symptoms and postoperative radiation remains the cornerstone of therapy with no proven benefit of adding chemotherapy. Low KPS, age ≥ 40 and higher tumor grade have a negative impact on overall survival

  9. Organization of the auditory brainstem in a lizard, Gekko gecko. I. Auditory nerve, cochlear nuclei, and superior olivary nuclei

    DEFF Research Database (Denmark)

    Tang, Y. Z.; Christensen-Dalsgaard, J.; Carr, C. E.

    2012-01-01

    We used tract tracing to reveal the connections of the auditory brainstem in the Tokay gecko (Gekko gecko). The auditory nerve has two divisions, a rostroventrally directed projection of mid- to high best-frequency fibers to the nucleus angularis (NA) and a more dorsal and caudal projection of lo...... of auditory connections in lizards and archosaurs but also different processing of low- and high-frequency information in the brainstem. J. Comp. Neurol. 520:17841799, 2012. (C) 2011 Wiley Periodicals, Inc...

  10. Lung inflammation induces IL-1β expression in hypoglossal neurons in rat brainstem

    Science.gov (United States)

    Jafri, Anjum; Belkadi, Abdelmadjid; Zaidi, Syed I. A.; Getsy, Paulina; Wilson, Christopher G.; Martin, Richard J.

    2013-01-01

    Perinatal inflammation is associated with respiratory morbidity. Immune modulation of brainstem respiratory control centers may provide a link for this pathobiology. We exposed 11-day old rats to intratracheal lipopolysaccharide (LPS, 0.5 µg/g) to test the hypothesis that intrapulmonary inflammation increases expression of the proinflammatory cytokine IL-1β within respiratory-related brainstem regions. Intratracheal LPS resulted in a 32% increase in IL-1β protein expression in the medulla oblongata. In situ hybridization showed increased intensity of IL-1β mRNA but no change in neuronal numbers. Co-localization experiments showed that hypoglossal neurons express IL-1β mRNA and immunostaining showed a 43% increase in IL-1β protein-expressing cells after LPS exposure. LPS treatment also significantly increased microglial cell numbers though they did not express IL-1β mRNA. LPS-induced brainstem expression of neuronal IL-1β mRNA and protein may have implications for our understanding of the vulnerability of neonatal respiratory control in response to a peripheral pro-inflammatory stimulus. PMID:23648475

  11. Effectiveness of interferon-[beta], ACNU, and radiation therapy in pediatric patients with brainstem glioma

    Energy Technology Data Exchange (ETDEWEB)

    Wakabayashi, Toshihiko; Yoshida, Jun; Mizuno, Masaaki; Sugita, Kenichiro [Nagoya Univ. (Japan). Faculty of Medicine; Kito, Akira

    1992-12-01

    Sixteen pediatric patients with brainstem glioma were treated with a combination of interferon-[beta], 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl -3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU), and radiation therapy (IAR therapy). All patients received 1-1.5 million IU/day of interferon-[beta] intravenously for 1 week of each 6-week cycle. In addition, ACNU (2-3 mg/kg) was given on the 2nd day of each cycle. Conventional focal irradiation (1.5-2 Gy/day for 5 days to a total dosage of 40-60 Gy) was administered beginning on day 3. Patients underwent at least two 6-week cycles. Adverse effects included nausea, vomiting, and myelosuppression, but were mild and transient. Response to treatment was evaluated by the reduction in tumor size measured on postcontrast computed tomographic scans and magnetic resonance images. Responses occurred in 10 of 11 patients with the intrinsic type of brainstem glioma, including three complete and seven partial responses. Two of the five patients with exophytic type gliomas partially responded. The median survival was 15.7 months, a remarkable improvement over the natural course of this disease. These results indicate that IAR therapy is a useful primary treatment for pediatric patients with brainstem gliomas. (author).

  12. Awake craniotomy for assisting placement of auditory brainstem implant in NF2 patients.

    Science.gov (United States)

    Zhou, Qiangyi; Yang, Zhijun; Wang, Zhenmin; Wang, Bo; Wang, Xingchao; Zhao, Chi; Zhang, Shun; Wu, Tao; Li, Peng; Li, Shiwei; Zhao, Fu; Liu, Pinan

    2018-06-01

    Auditory brainstem implants (ABIs) may be the only opportunity for patients with NF2 to regain some sense of hearing sensation. However, only a very small number of individuals achieved open-set speech understanding and high sentence scores. Suboptimal placement of the ABI electrode array over the cochlear nucleus may be one of main factors for poor auditory performance. In the current study, we present a method of awake craniotomy to assist with ABI placement. Awake surgery and hearing test via the retrosigmoid approach were performed for vestibular schwannoma resections and auditory brainstem implantations in four patients with NF2. Auditory outcomes and complications were assessed postoperatively. Three of 4 patients who underwent awake craniotomy during ABI surgery received reproducible auditory sensations intraoperatively. Satisfactory numbers of effective electrodes, threshold levels and distinct pitches were achieved in the wake-up hearing test. In addition, relatively few electrodes produced non-auditory percepts. There was no serious complication attributable to the ABI or awake craniotomy. It is safe and well tolerated for neurofibromatosis type 2 (NF2) patients using awake craniotomy during auditory brainstem implantation. This method can potentially improve the localization accuracy of the cochlear nucleus during surgery.

  13. Selective attention modulates human auditory brainstem responses: relative contributions of frequency and spatial cues.

    Directory of Open Access Journals (Sweden)

    Alexandre Lehmann

    Full Text Available Selective attention is the mechanism that allows focusing one's attention on a particular stimulus while filtering out a range of other stimuli, for instance, on a single conversation in a noisy room. Attending to one sound source rather than another changes activity in the human auditory cortex, but it is unclear whether attention to different acoustic features, such as voice pitch and speaker location, modulates subcortical activity. Studies using a dichotic listening paradigm indicated that auditory brainstem processing may be modulated by the direction of attention. We investigated whether endogenous selective attention to one of two speech signals affects amplitude and phase locking in auditory brainstem responses when the signals were either discriminable by frequency content alone, or by frequency content and spatial location. Frequency-following responses to the speech sounds were significantly modulated in both conditions. The modulation was specific to the task-relevant frequency band. The effect was stronger when both frequency and spatial information were available. Patterns of response were variable between participants, and were correlated with psychophysical discriminability of the stimuli, suggesting that the modulation was biologically relevant. Our results demonstrate that auditory brainstem responses are susceptible to efferent modulation related to behavioral goals. Furthermore they suggest that mechanisms of selective attention actively shape activity at early subcortical processing stages according to task relevance and based on frequency and spatial cues.

  14. Impact of monaural frequency compression on binaural fusion at the brainstem level.

    Science.gov (United States)

    Klauke, Isabelle; Kohl, Manuel C; Hannemann, Ronny; Kornagel, Ulrich; Strauss, Daniel J; Corona-Strauss, Farah I

    2015-08-01

    A classical objective measure for binaural fusion at the brainstem level is the so-called β-wave of the binaural interaction component (BIC) in the auditory brainstem response (ABR). However, in some cases it appeared that a reliable detection of this component still remains a challenge. In this study, we investigate the wavelet phase synchronization stability (WPSS) of ABR data for the analysis of binaural fusion and compare it to the BIC. In particular, we examine the impact of monaural nonlinear frequency compression on binaural fusion. As the auditory system is tonotopically organized, an interaural frequency mismatch caused by monaural frequency compression could negatively effect binaural fusion. In this study, only few subjects showed a detectable β-wave and in most cases only for low ITDs. However, we present a novel objective measure for binaural fusion that outperforms the current state-of-the-art technique (BIC): the WPSS analysis showed a significant difference between the phase stability of the sum of the monaurally evoked responses and the phase stability of the binaurally evoked ABR. This difference could be an indicator for binaural fusion in the brainstem. Furthermore, we observed that monaural frequency compression could indeed effect binaural fusion, as the WPSS results for this condition vary strongly from the results obtained without frequency compression.

  15. Enhanced brainstem and cortical evoked response amplitudes: single-trial covariance analysis.

    Science.gov (United States)

    Galbraith, G C

    2001-06-01

    The purpose of the present study was to develop analytic procedures that improve the definition of sensory evoked response components. Such procedures could benefit all recordings but would especially benefit difficult recordings where many trials are contaminated by muscle and movement artifacts. First, cross-correlation and latency adjustment analyses were applied to the human brainstem frequency-following response and cortical auditory evoked response recorded on the same trials. Lagged cross-correlation functions were computed, for each of 17 subjects, between single-trial data and templates consisting of the sinusoid stimulus waveform for the brainstem response and the subject's own smoothed averaged evoked response P2 component for the cortical response. Trials were considered in the analysis only if the maximum correlation-squared (r2) exceeded .5 (negatively correlated trials were thus included). Identical correlation coefficients may be based on signals with quite different amplitudes, but it is possible to assess amplitude by the nonnormalized covariance function. Next, an algorithm is applied in which each trial with negative covariance is matched to a trial with similar, but positive, covariance and these matched-trial pairs are deleted. When an evoked response signal is present in the data, the majority of trials positively correlate with the template. Thus, a residual of positively correlated trials remains after matched covariance trials are deleted. When these residual trials are averaged, the resulting brainstem and cortical responses show greatly enhanced amplitudes. This result supports the utility of this analysis technique in clarifying and assessing evoked response signals.

  16. Features of the brainstem and tentorial foramen relationship and their practical value

    Directory of Open Access Journals (Sweden)

    O. V. Redyakina

    2016-11-01

    Full Text Available Objective. Establish the morphological features and practical significance of the tentorial-stem relationship from the position of individual anatomical variability. Methods: head morphometry, macro and microscopic examination of the brainstem, morphometry of the brainstem and its departments, tentorial aperture morphometry, foramen magnum craniometry, manufacture of corrosion molds of the posterior cranial fossa, statistical processing of the results, computer-graphic modeling of the brainstem and surrounding formations. Results.  In the course of the study, the features of the individual variability of the tentorial foramen form were established, namely: shortened-expanded and oval-convex forms were defined in brachycephalic; in dolichocephalic - oblong-narrowed and elongated-conical. At the same time, a number of existing sizes and forms of the tentorial-stem spaces were noted. Among them, four main ones are described: front, side (right and left and rear. They have individual characteristics. Thus, in the brachycephalic we define lateral holes, due to the convexity of the tentorial margins. In dolichocephalic - front and back gaps, depending on the characteristics of their elongations. The obtained data are of great importance for the craniotopographic justification of the tentorial-stem wedges, which are formed with tumors which located here. In our opinion, tumors have the greatest possibility of passage through the left or right lateral intervals in people with a brachymorph form of the head, and through the anterior and posterior intervals - in people with meso- and dolichomorph forms of the head.

  17. Blast overpressure induced axonal injury changes in rat brainstem and spinal cord

    Directory of Open Access Journals (Sweden)

    Srinivasu Kallakuri

    2015-01-01

    Full Text Available Introduction: Blast induced neurotrauma has been the signature wound in returning soldiers from the ongoing wars in Iraq and Afghanistan. Of importance is understanding the pathomechansim(s of blast overpressure (OP induced axonal injury. Although several recent animal models of blast injury indicate the neuronal and axonal injury in various brain regions, animal studies related to axonal injury in the white matter (WM tracts of cervical spinal cord are limited. Objective: The purpose of this study was to assess the extent of axonal injury in WM tracts of cervical spinal cord in male Sprague Dawley rats subjected to a single insult of blast OP. Materials and Methods: Sagittal brainstem sections and horizontal cervical spinal cord sections from blast and sham animals were stained by neurofilament light (NF-L chain and beta amyloid precursor protein immunocytochemistry and observed for axonal injury changes. Results: Observations from this preliminary study demonstrate axonal injury changes in the form of prominent swellings, retraction bulbs, and putative signs of membrane disruptions in the brainstem and cervical spinal cord WM tracts of rats subjected to blast OP. Conclusions: Prominent axonal injury changes following the blast OP exposure in brainstem and cervical spinal WM tracts underscores the need for careful evaluation of blast induced injury changes and associated symptoms. NF-L immunocytochemistry can be considered as an additional tool to assess the blast OP induced axonal injury.

  18. The inter-observer agreement in the assessment of carotid plaque neovascularization by contrast-enhanced ultrasonography: The impact of plaque thickness.

    Science.gov (United States)

    Chen, Jian; Zhang, Yan-Ming; Song, Ze-Zhou; Fu, Yan-Fei; Geng, Yu

    2018-04-10

    The interobserver agreement in the assessment of the grade of carotid plaque neovascularization by contrast-enhanced ultrasonography is poorly established. We examined 140 carotid plaques in 66 patients (all patients had bilateral plaques, and 8 patients had 2 plaques on one side). We performed conventional and contrast-enhanced ultrasonography to analyze the presence of carotid plaque neovascularization, which was graded by two independent observers whose interobserver agreement (κ) was evaluated according to the thickness of carotid plaque. For all carotid plaques, the mean κ was 0.689 (95% confidence interval 0.604-0.774). It was 0.689 (0.569-0.808), 0.637 (0.487-0.787), and 0.740 (0.585-0.896), respectively for carotid plaques with maximal thickness 3 mm. The interobserver agreement for assessing carotid plaque neovascularization by using contrast-enhanced ultrasonography is substantial and acceptable for research purposes, regardless of the maximal thickness of the plaque. © 2018 Wiley Periodicals, Inc.

  19. Gene expression levels of matrix metalloproteinases in human atherosclerotic plaques and evaluation of radiolabeled inhibitors as imaging agents for plaque vulnerability

    International Nuclear Information System (INIS)

    Müller, Adrienne; Krämer, Stefanie D.; Meletta, Romana; Beck, Katharina; Selivanova, Svetlana V.; Rancic, Zoran; Kaufmann, Philipp A.; Vos, Bernhard; Meding, Jörg; Stellfeld, Timo; Heinrich, Tobias K.; Bauser, Marcus; Hütter, Joachim; Dinkelborg, Ludger M.; Schibli, Roger; Ametamey, Simon M.

    2014-01-01

    Introduction: Atherosclerotic plaque rupture is the primary cause for myocardial infarction and stroke. During plaque progression macrophages and mast cells secrete matrix-degrading proteolytic enzymes, such as matrix metalloproteinases (MMPs). We studied levels of MMPs and tissue inhibitor of metalloproteinases-3 (TIMP-3) in relation to the characteristics of carotid plaques. We evaluated in vitro two radiolabeled probes targeting active MMPs towards non-invasive imaging of rupture-prone plaques. Methods: Human carotid plaques obtained from endarterectomy were classified into stable and vulnerable by visual and histological analysis. MMP-1, MMP-2, MMP-8, MMP-9, MMP-10, MMP-12, MMP-14, TIMP-3, and CD68 levels were investigated by quantitative polymerase chain reaction. Immunohistochemistry was used to localize MMP-2 and MMP-9 with respect to CD68-expressing macrophages. Western blotting was applied to detect their active forms. A fluorine-18-labeled MMP-2/MMP-9 inhibitor and a tritiated selective MMP-9 inhibitor were evaluated by in vitro autoradiography as potential lead structures for non-invasive imaging. Results: Gene expression levels of all MMPs and CD68 were elevated in plaques. MMP-1, MMP-9, MMP-12 and MMP-14 were significantly higher in vulnerable than stable plaques. TIMP-3 expression was highest in stable and low in vulnerable plaques. Immunohistochemistry revealed intensive staining of MMP-9 in vulnerable plaques. Western blotting confirmed presence of the active form in plaque lysates. In vitro autoradiography showed binding of both inhibitors to stable and vulnerable plaques. Conclusions: MMPs differed in their expression patterns among plaque phenotypes, providing possible imaging targets. The two tested MMP-2/MMP-9 and MMP-9 inhibitors may be useful to detect atherosclerotic plaques, but not the vulnerable lesions selectively

  20. Carotid plaque, intima-media thickness, and incident aortic stenosis

    DEFF Research Database (Denmark)

    Martinsson, Andreas; Östling, Gerd; Persson, Margaretha

    2014-01-01

    AS in a prospective population-based study. APPROACH AND RESULTS: A random sample of participants (age, 45-68 years) in the population-based Malmö Diet and Cancer Study underwent B-mode ultrasound with measurements of IMT and the presence of plaque in the common carotid artery (n=5079). Potential risk factors...

  1. Symptomatic Plaque Form Gastric Candidiasis in a Patient with ...

    African Journals Online (AJOL)

    We report the occurrence of diffuse plaque deposits of candida in the gastric antrum of a 36 year old female patient with chronic kidney disease (CKD) on maintenance haemodialysis who presented with epigastric pain, nausea, vomiting and passage of black stools for two weeks. Upper gastrointestinal endoscopy revealed ...

  2. Microbial profiling of dental plaque from mechanically ventilated patients.

    Science.gov (United States)

    Sands, Kirsty M; Twigg, Joshua A; Lewis, Michael A O; Wise, Matt P; Marchesi, Julian R; Smith, Ann; Wilson, Melanie J; Williams, David W

    2016-02-01

    Micro-organisms isolated from the oral cavity may translocate to the lower airways during mechanical ventilation (MV) leading to ventilator-associated pneumonia (VAP). Changes within the dental plaque microbiome during MV have been documented previously, primarily using culture-based techniques. The aim of this study was to use community profiling by high throughput sequencing to comprehensively analyse suggested microbial changes within dental plaque during MV. Bacterial 16S rDNA gene sequences were obtained from 38 samples of dental plaque sampled from 13 mechanically ventilated patients and sequenced using the Illumina platform. Sequences were processed using Mothur, applying a 97% gene similarity cut-off for bacterial species level identifications. A significant 'microbial shift' occurred in the microbial community of dental plaque during MV for nine out of 13 patients. Following extubation, or removal of the endotracheal tube that facilitates ventilation, sampling revealed a decrease in the relative abundance of potential respiratory pathogens and a compositional change towards a more predominantly (in terms of abundance) oral microbiota including Prevotella spp., and streptococci. The results highlight the need to better understand microbial shifts in the oral microbiome in the development of strategies to reduce VAP, and may have implications for the development of other forms of pneumonia such as community-acquired infection.

  3. Paraclinical Effects of Miswak Extract on Dental Plaque

    Directory of Open Access Journals (Sweden)

    Hamid Reza Poureslami

    2007-01-01

    Full Text Available Introduction: The Persian toothbrush tree or Miswak (Salvadora Persica L. has been used as a brushing stick for more than 1,300 years. Pharmacological studies indicated antibacterial and antiinflammatory activities of Miswak extract. The present study was performed to determine antibacterial effects of Miswak extract.Material and Methods: The present experimental research involved three in vitro studies including: 1 in vitro testing of the effect of Miswak extract on selected bacteria; 2 comparing the paraclinical effects of Iranian toothpaste containing Miswak extract and placebo toothpaste on dental plaque; and 3 comparing the antibacterial effect of Iranian toothpaste with Swiss toothpaste(Quail Miswak on dental plaque. The disc diffusion method was used to test bacterial sensitivity of toothpastes. Data were analyzed by paired t-test and ANOVA.Results: In the first study, Miswak extract inhibited the growth of some dental plaque bacteria. In the second study, antibacterial effect of the herbal toothpaste was significantly greater than that of the placebo (P =0.002. In the third study, four samples of dental plaque bacteria were used and there was no difference between the antibacterial effects of Swiss and Iranian herbal toothpastes (P =0.66.Conclusion: Due to antimicrobial effects of Miswak extract, its use in mouth rinses and toothpastes is highly recommended.

  4. Can chemical mouthwash agents achieve plaque/gingivitis control?

    NARCIS (Netherlands)

    van der Weijden, F.A.; Van der Sluijs, E.; Ciancio, S.G.; Slot, D.E.

    2015-01-01

    Key points • Oral health is important since the mouth is the gateway to the human body. Bacteria are always present in the oral cavity and when not frequently removed the dental plaque biofilm leads to the development of oral disease. • Over the past decades, the use of mouthwashes has become

  5. Development of sarcoidosis during adalimumab therapy for chronic plaque psoriasis.

    Science.gov (United States)

    Marcella, Stefanie; Welsh, Belinda; Foley, Peter

    2011-08-01

    A 38-year-old woman developed clinical, biochemical, radiological and histopathological evidence of cutaneous and pulmonary sarcoidosis 5 months after commencing adalimumab for chronic plaque psoriasis. Signs and symptoms resolved within 3 months of cessation of adalimumab. © 2010 The Authors. Australasian Journal of Dermatology © 2010 The Australasian College of Dermatologists.

  6. Study of isodose curves of an eye brachytherapy plaque

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Marcos R.O.; Mourao, Arnaldo P., E-mail: marcos.robertto@hotmail.com, E-mail: seg@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil); Grynberg, Suely E., E-mail: aprata@des.cefetmg.br [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil). Nucleo de Engenharia Hospitalar

    2015-07-01

    The use eye plaque brachytherapy for intraocular tumors treatment is a process designed to protect healthy eye structures, as well as visual functions. It replaces enucleation when possible. The knowledge of the dose spatial distribution inside the eyeball and adjacent structures is very important to obtain the therapeutic dose, minimize the side effects and ensure efficiency in the process. Small variations in positioning the plaque on the ocular surface may generate a less effective treatment. Thus, in this work an eyeball phantom and a seed accommodation system similar to a commercially eye plaque model ROPES with diameter of 15 mm, were developed both in solid water Gammex 457 to conduct the study of the possible variation in the dose deposition inside the eye phantom. Radiochromic films were used to record isodose curves of two orthogonal plans within the simulator. The results showed that there is a difference in the dose deposition for the two orthogonal plans studied. This difference is 8.33% higher for the maximum dose value. Thus, a difference in dose that occurs due to the asymmetrical distribution of seeds on the eye plaque may interfere with the treatment, making it less effective. (author)

  7. Study of isodose curves of an eye brachytherapy plaque

    International Nuclear Information System (INIS)

    Costa, Marcos R.O.; Mourao, Arnaldo P.; Grynberg, Suely E.

    2015-01-01

    The use eye plaque brachytherapy for intraocular tumors treatment is a process designed to protect healthy eye structures, as well as visual functions. It replaces enucleation when possible. The knowledge of the dose spatial distribution inside the eyeball and adjacent structures is very important to obtain the therapeutic dose, minimize the side effects and ensure efficiency in the process. Small variations in positioning the plaque on the ocular surface may generate a less effective treatment. Thus, in this work an eyeball phantom and a seed accommodation system similar to a commercially eye plaque model ROPES with diameter of 15 mm, were developed both in solid water Gammex 457 to conduct the study of the possible variation in the dose deposition inside the eye phantom. Radiochromic films were used to record isodose curves of two orthogonal plans within the simulator. The results showed that there is a difference in the dose deposition for the two orthogonal plans studied. This difference is 8.33% higher for the maximum dose value. Thus, a difference in dose that occurs due to the asymmetrical distribution of seeds on the eye plaque may interfere with the treatment, making it less effective. (author)

  8. Ichthyosiform large plaque parapsoriasis: report of a rare entity.

    Science.gov (United States)

    Nag, Falguni; Ghosh, Arghyaprasun; Biswas, Projna; Chatterjee, Gobinda; Biswas, Saugato

    2013-09-01

    Large plaque parapsoriasis (LPP) is an idiopathic, chronic scaly dermatosis classified within parapsoriasis group of diseases, occurring commonly in middle aged patients of all races and geographic regions. LPP and its variants are closely related to the patch stage of mycosis fungoides. The two types of LPP mostly described are the poikilodermatous and retiform parapsoriasis. We are reporting an ichthyosiform LPP for its rarity.

  9. Complications of cobalt plaque therapy of choroidal malanomas

    International Nuclear Information System (INIS)

    Char, D.H.; Lonn, L.I.; Margolis, L.W.

    1977-01-01

    We treated a small series of patients with choroidal melanomas with radioactive cobalt plaques. To assess the effectiveness of radiation, we performed radioactive phosphorus ( 32 P) uptake determinations before and after treatment. The 32 P results did not tumor destruction. In five of seven patients with posterior pole melanomas, radiation retinopathy developed after treatment with resultant decrease in vision

  10. Topical tazarotene vs. coal tar in stable plaque psoriasis

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, U.; Kaur, I.; Dogra, S.; De, D.; Kumar, B. [Postgraduate Institute of Medical Education & Research, Chandigarh (India)

    2010-07-15

    The efficacy of topical tazarotene has not previously been compared with the conventional topical treatment of crude coal tar (CCT) in stable plaque psoriasis. In this nonblinded side-to-side comparison study, patients with chronic stable plaque psoriasis, who had bilaterally symmetrical plaques on the limbs, applied 0.1% tazarotene gel on the right side and 5% CCT ointment on the left side once daily for 12 weeks followed by an 8-week treatment-free follow up period. Severity of psoriatic lesions and response to treatment was evaluated by scoring erythema, scaling and induration (ESI). Of 30 patients recruited, 27 could be assessed. In the per-protocol analysis, the mean percentage reduction in ESI score at the end of the treatment period was 74.15% {+-} 9.43 and 77.37% {+-} 10.93 with tazarotene and CCT, respectively (P {gt} 0.05). A reduction in ESI score of {gt} 75% was seen in 11 (40.74%) and 16 (59.26%) patients with tazarotene and CCT, respectively, at the end of 12 weeks. Side-effects were seen in 48.14% of patients treated with tazarotene, but in no patient treated with CCT. Tazarotene 0.1% gel has comparable clinical efficacy to CCT 5% ointment. CCT ointment remains a cost-effective therapy for plaque psoriasis.

  11. Cryotherapy increases features of plaque stability in atherosclerotic rabbits.

    Science.gov (United States)

    Verheye, Stefan; Roth, Lynn; De Meyer, Inge; Van Hove, Cor E; Nahon, Daniel; Santoianni, Domenic; Yianni, John; Martinet, Wim; Buchbinder, Maurice; De Meyer, Guido R Y

    2016-08-20

    In the last 10 years, cryotherapy has been investigated as a new technology to treat vascular disease. The efficiency of cryotherapy in stabilising atherosclerotic plaques has never been described. The purpose of the present study was to evaluate the effect of catheter-based cryotherapy on atherosclerotic plaque composition in a rabbit model of atherosclerosis. Twenty-four New Zealand white rabbits were fed a 0.3% cholesterol-supplemented diet for 24 weeks. At two predefined sites of the atherosclerotic thoracic aorta, catheter-based cryotherapy, applying either single-dose, double-dose cryotherapy or control inflation, was performed after randomisation. Rabbits were continued on a cholesterol-supplemented diet for one day (acute) or four weeks (chronic). One day after cryotherapy, apoptotic cell death of smooth muscle cells (SMCs) and endothelial cells (ECs) was observed, whereas macrophages were unaffected. Four weeks later, the amount of SMCs was restored, the EC layer was regenerated, and a subendothelial macrophage-free layer was formed, indicative of a more stable plaque. In addition, both the thickness and the type I collagen content of the fibrous cap were increased. The present study demonstrated that cryotherapy is feasible and appears to stabilise atherosclerotic plaques in a rabbit model.

  12. Atherosclerotic plaque destabilization in Mice: A comparative study

    NARCIS (Netherlands)

    H. Hartwig (Helene); C. Silvestre-Roig (Carlos); J. Hendrikse (Jeffrey); L. Beckers (Linda); N. Paulin (Nicole); K. van der Heiden (Kim); Q. Braster (Quinte); M. Drechsler (Maik); M.J. Daemen (Mat); E. Lutgens; O. Soehnlein (Oliver)

    2015-01-01

    textabstractAtherosclerosis-Associated diseases are the main cause ofmortality and morbidity in western societies. The progression of atherosclerosis is a dynamic process evolving from early to advanced lesions thatmay become rupture-prone vulnerable plaques. Acute coronary syndromes are the

  13. Atherosclerotic Plaque Destabilization in Mice: A Comparative Study

    NARCIS (Netherlands)

    Hartwig, Helene; Silvestre-Roig, Carlos; Hendrikse, Jeffrey; Beckers, Linda; Paulin, Nicole; van der Heiden, Kim; Braster, Quinte; Drechsler, Maik; Daemen, Mat J.; Lutgens, Esther; Soehnlein, Oliver

    2015-01-01

    Atherosclerosis-associated diseases are the main cause of mortality and morbidity in western societies. The progression of atherosclerosis is a dynamic process evolving from early to advanced lesions that may become rupture-prone vulnerable plaques. Acute coronary syndromes are the clinical

  14. MR Microimaging of amyloid plaques in Alzheimer's disease transgenic mice

    International Nuclear Information System (INIS)

    Wengenack, Thomas M.; Poduslo, Joseph F.; Jack, Clifford R.; Garwood, Michael

    2008-01-01

    Alzheimer's disease (AD) is the most prevalent neurological condition affecting industrialized nations and will rapidly become a healthcare crisis as the population ages. Currently, the post-mortem histological observation of amyloid plaques and neurofibrillary tangles is the only definitive diagnosis available for AD. A pre-mortem biological or physiological marker specific for AD used in conjunction with current neurological and memory testing could add a great deal of confidence to the diagnosis of AD and potentially allow therapeutic intervention much earlier in the disease process. Our group has developed MRI techniques to detect individual amyloid plaques in AD transgenic mouse brain in vivo. We are also developing contrast-enhancing agents to increase the specificity of detection of amyloid plaques. Such in vivo imaging of amyloid plaques will also allow the evaluation of anti-amyloid therapies being developed by the pharmaceutical industry in pre-clinical trials of AD transgenic mice. This short review briefly discusses our progress in these areas. (orig.)

  15. HDL-mimetic PLGA nanoparticle to target atherosclerosis plaque macrophages

    NARCIS (Netherlands)

    Sanchez-Gaytan, Brenda L.; Fay, Francois; Lobatto, Mark E.; Tang, Jun; Ouimet, Mireille; Kim, Yongtae; van der Staay, Susanne E. M.; van Rijs, Sarian M.; Priem, Bram; Zhang, Liangfang; Fisher, Edward A.; Moore, Kathryn J.; Langer, Robert; Fayad, Zahi A.; Mulder, Willem J. M.

    2015-01-01

    High-density lipoprotein (HDL) is a natural nanoparticle that exhibits an intrinsic affinity for atherosclerotic plaque macrophages. Its natural targeting capability as well as the option to incorporate lipophilic payloads, e.g., imaging or therapeutic components, in both the hydrophobic core and

  16. Associations of coronary artery calcified plaque density with mortality in type 2 diabetes: the Diabetes Heart Study.

    Science.gov (United States)

    Raffield, Laura M; Cox, Amanda J; Criqui, Michael H; Hsu, Fang-Chi; Terry, James G; Xu, Jianzhao; Freedman, Barry I; Carr, J Jeffrey; Bowden, Donald W

    2018-05-11

    Coronary artery calcified plaque (CAC) is strongly predictive of cardiovascular disease (CVD) events and mortality, both in general populations and individuals with type 2 diabetes at high risk for CVD. CAC is typically reported as an Agatston score, which is weighted for increased plaque density. However, the role of CAC density in CVD risk prediction, independently and with CAC volume, remains unclear. We examined the role of CAC density in individuals with type 2 diabetes from the family-based Diabetes Heart Study and the African American-Diabetes Heart Study. CAC density was calculated as mass divided by volume, and associations with incident all-cause and CVD mortality [median follow-up 10.2 years European Americans (n = 902, n = 286 deceased), 5.2 years African Americans (n = 552, n = 93 deceased)] were examined using Cox proportional hazards models, independently and in models adjusted for CAC volume. In European Americans, CAC density, like Agatston score and volume, was consistently associated with increased risk of all-cause and CVD mortality (p ≤ 0.002) in models adjusted for age, sex, statin use, total cholesterol, HDL, systolic blood pressure, high blood pressure medication use, and current smoking. However, these associations were no longer significant when models were additionally adjusted for CAC volume. CAC density was not significantly associated with mortality, either alone or adjusted for CAC volume, in African Americans. CAC density is not associated with mortality independent from CAC volume in European Americans and African Americans with type 2 diabetes.

  17. Three-dimensional dosimetry imaging of I-125 plaque for eye cancer treatment

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, M.; Green, J.; Petasecca, M.; Lerch, M.L.F.; Cutajar, D.; Franklin, D. [Centre for Medical Radiation Physics-University of Wollongong, Northfileds Avenue, Wollongong 2500 NSW (Australia); Jakubek, J. [Institute of Experimental and Applied Physics, Czech Technical University in Prague, 12800 Prague 2 (Czech Republic); Carolan, M.G. [Centre for Medical Radiation Physics-University of Wollongong, Northfileds Avenue, Wollongong 2500 NSW (Australia); Illawarra Cancer Care Centre, Wollongong 2500 NSW (Australia); Conway, M. [Sydney Eye Hospital-Faculty of Medicine, The University of Sydney, Sydney 2006 NSW (Australia); Pospisil, S. [Institute of Experimental and Applied Physics, Czech Technical University in Prague, 12800 Prague 2 (Czech Republic); Kron, T. [Peter MacCallum Cancer Centre, Melbourne Vic 8006 (Australia); Metcalfe, P. [Centre for Medical Radiation Physics-University of Wollongong, Northfileds Avenue, Wollongong 2500 NSW (Australia); Zaider, M. [Memorial Sloan-Kettering Cancer Centre, New York, NY 10021 (United States); Rosenfeld, A.B., E-mail: anatoly@uow.edu.au [Centre for Medical Radiation Physics-University of Wollongong, Northfileds Avenue, Wollongong 2500 NSW (Australia)

    2011-05-15

    Treatment of ocular cancers using eye plaque brachytherapy is now an established medical procedure. However, current QA for these eye plaques is quite rudimentary, limiting the opportunities for precise pre-tumour plaque customisation. This paper proposes and experimentally validates a new technique for imaging of eye plaque dose distributions using a high-resolution pixelated silicon detector. Results are presented demonstrating the 2D and 3D isodose surfaces produced using experimental data collected using this method.

  18. Three-dimensional dosimetry imaging of I-125 plaque for eye cancer treatment

    International Nuclear Information System (INIS)

    Weaver, M.; Green, J.; Petasecca, M.; Lerch, M.L.F.; Cutajar, D.; Franklin, D.; Jakubek, J.; Carolan, M.G.; Conway, M.; Pospisil, S.; Kron, T.; Metcalfe, P.; Zaider, M.; Rosenfeld, A.B.

    2011-01-01

    Treatment of ocular cancers using eye plaque brachytherapy is now an established medical procedure. However, current QA for these eye plaques is quite rudimentary, limiting the opportunities for precise pre-tumour plaque customisation. This paper proposes and experimentally validates a new technique for imaging of eye plaque dose distributions using a high-resolution pixelated silicon detector. Results are presented demonstrating the 2D and 3D isodose surfaces produced using experimental data collected using this method.

  19. A framework for the co-registration of hemodynamic forces and atherosclerotic plaque components

    OpenAIRE

    Canton, Gador; Chiu, Bernard; Chen, Huijun; Chen, Yimin; Hatsukami, Thomas S.; Kerwin, William S.; Yuan, Chun

    2013-01-01

    Local hemodynamic forces, such as wall shear stress, are thought to trigger cellular and molecular mechanisms that determine atherosclerotic plaque vulnerability to rupture. Magnetic resonance imaging (MRI) has emerged as a powerful tool to characterize human carotid atherosclerotic plaque composition and morphology, and to identify plaque features shown to be key determinants of plaque vulnerability. Image-based computational fluid dynamics (CFD) has allowed researchers to obtain time-resolv...

  20. Multi-feature-based plaque characterization in ex vivo MRI trained by registration to 3D histology

    International Nuclear Information System (INIS)

    Van Engelen, Arna; Niessen, Wiro J; Klein, Stefan; De Bruijne, Marleen; Groen, Harald C; Wentzel, Jolanda J; Verhagen, Hence JM; Lugt, Aad van der

    2012-01-01

    We present a new method for automated characterization of atherosclerotic plaque composition in ex vivo MRI. It uses MRI intensities as well as four other types of features: smoothed, gradient magnitude and Laplacian images at several scales, and the distances to the lumen and outer vessel wall. The ground truth for fibrous, necrotic and calcified tissue was provided by histology and μCT in 12 carotid plaque specimens. Semi-automatic registration of a 3D stack of histological slices and μCT images to MRI allowed for 3D rotations and in-plane deformations of histology. By basing voxelwise classification on different combinations of features, we evaluated their relative importance. To establish whether training by 3D registration yields different results than training by 2D registration, we determined plaque composition using (1) a 2D slice-based registration approach for three manually selected MRI and histology slices per specimen, and (2) an approach that uses only the three corresponding MRI slices from the 3D-registered volumes. Voxelwise classification accuracy was best when all features were used (73.3 ± 6.3%) and was significantly better than when only original intensities and distance features were used (Friedman, p < 0.05). Although 2D registration or selection of three slices from the 3D set slightly decreased accuracy, these differences were non-significant. (paper)

  1. Efficacy of Methotrexate in patients with plaque type psoriasis

    Science.gov (United States)

    Haider, Sabiqa; Wahid, Zarnaz; Najam-us-Saher; Riaz, Farzana

    2014-01-01

    Objective: To assess the efficacy of Methotrexate in patients with plaque type psoriasis. Methods: This descriptive study was conducted in the department of Dermatology, Civil Hospital Karachi from September 2009 to March 2010. Seventy three patients between 18 to 50 years of age suffering from plaque type psoriasis with PASI score of >10 were included in the study after taking the informed consent. Oral methotrexate in a dose of 7.5 mg/week was given for 8 weeks. The data collected included demographic profile (age and gender), duration of disease, site of involvement, size of plaque, severity of plaque measured by Psoriasis Area and Severity Index (PASI) score before starting the treatment and at the end of treatment. Efficacy was labeled with a PASI score of ≤5 at the end of 8 weeks. Results: Out of 73 patients there were 45 (61.6%) males and 28 (38.4%) females. The mean ±SD age was 40.0±12.6 years. The mean baseline PASI score showed clear and comparable improvement from a mean ± SD PASI score of 14.8±4.2 to 4.9±4.3.Twenty nine (40%) patients had an almost complete remission during the 8 weeks of treatment. Partial remission was achieved in 44 (60%) patients. The clearance time for psoriasis ranged from 5-7 weeks (mean 6±0.89 weeks). Conclusion: Treatment with methotrexate for chronic plaque psoriasis brings satisfactory disease control and improved quality of life. PMID:25225524

  2. Mechanical Characterization of Immature Porcine Brainstem in Tension at Dynamic Strain Rates.

    Science.gov (United States)

    Zhao, Hui; Yin, Zhiyong; Li, Kui; Liao, Zhikang; Xiang, Hongyi; Zhu, Feng

    2016-01-21

    Many brain injury cases involve pediatric road traffic accidents, and among these, brainstem injury causes disastrous outcomes. A thorough understanding of the tensile characterization of immature brainstem tissue is crucial in modeling traumatic brain injury sustained by children, but limited experimental data in tension is available for the immature brain tissue at dynamic strain rates. We harvested brainstem tissue from immature pigs (about 4 weeks old, and at a developmental stage similar to that of human toddlers) as a byproduct from a local slaughter house and very carefully prepared the samples. Tensile tests were performed on specimens at dynamic strain rates of 2/s, 20/s, and 100/s using a biological material instrument. The constitutive models, Fung, Ogden, Gent, and exponential function, for immature brainstem tissue material property were developed for the recorded experimental data using OriginPro 8.0 software. The t test was performed for infinitesimal shear modules. The curves of stress-versus-stretch ratio were convex in shape, and inflection points were found in all the test groups at the strain of about 2.5%. The average Lagrange stress of the immature brainstem specimen at the 30% strain at the strain rates of 2, 20, and 100/s was 273±114, 515±107, and 1121±197 Pa, respectively. The adjusted R-Square (R2) of Fung, Ogden, Gent, and exponential model was 0.820≤R2≤0.933, 0.774≤R2≤0.940, 0.650≤R2≤0.922, and 0.852≤R2≤0.981, respectively. The infinitesimal shear modulus of the strain energy functions showed a significant association with the strain rate (pmaterial in dynamic tensile tests, and the tissue becomes stiffer with increased strain rate. The reported results may be useful in the study of brain injuries in children who sustain injuries in road traffic accidents. Further research in more detail should be performed in the future.

  3. Robust Machine Learning-Based Correction on Automatic Segmentation of the Cerebellum and Brainstem.

    Directory of Open Access Journals (Sweden)

    Jun Yi Wang

    Full Text Available Automated segmentation is a useful method for studying large brain structures such as the cerebellum and brainstem. However, automated segmentation may lead to inaccuracy and/or undesirable boundary. The goal of the present study was to investigate whether SegAdapter, a machine learning-based method, is useful for automatically correcting large segmentation errors and disagreement in anatomical definition. We further assessed the robustness of the method in handling size of training set, differences in head coil usage, and amount of brain atrophy. High resolution T1-weighted images were acquired from 30 healthy controls scanned with either an 8-channel or 32-channel head coil. Ten patients, who suffered from brain atrophy because of fragile X-associated tremor/ataxia syndrome, were scanned using the 32-channel head coil. The initial segmentations of the cerebellum and brainstem were generated automatically using Freesurfer. Subsequently, Freesurfer's segmentations were both manually corrected to serve as the gold standard and automatically corrected by SegAdapter. Using only 5 scans in the training set, spatial overlap with manual segmentation in Dice coefficient improved significantly from 0.956 (for Freesurfer segmentation to 0.978 (for SegAdapter-corrected segmentation for the cerebellum and from 0.821 to 0.954 for the brainstem. Reducing the training set size to 2 scans only decreased the Dice coefficient ≤0.002 for the cerebellum and ≤ 0.005 for the brainstem compared to the use of training set size of 5 scans in corrective learning. The method was also robust in handling differences between the training set and the test set in head coil usage and the amount of brain atrophy, which reduced spatial overlap only by <0.01. These results suggest that the combination of automated segmentation and corrective learning provides a valuable method for accurate and efficient segmentation of the cerebellum and brainstem, particularly in large

  4. Processing Complex Sounds Passing through the Rostral Brainstem: The New Early Filter Model

    Science.gov (United States)

    Marsh, John E.; Campbell, Tom A.

    2016-01-01

    The rostral brainstem receives both “bottom-up” input from the ascending auditory system and “top-down” descending corticofugal connections. Speech information passing through the inferior colliculus of elderly listeners reflects the periodicity envelope of a speech syllable. This information arguably also reflects a composite of temporal-fine-structure (TFS) information from the higher frequency vowel harmonics of that repeated syllable. The amplitude of those higher frequency harmonics, bearing even higher frequency TFS information, correlates positively with the word recognition ability of elderly listeners under reverberatory conditions. Also relevant is that working memory capacity (WMC), which is subject to age-related decline, constrains the processing of sounds at the level of the brainstem. Turning to the effects of a visually presented sensory or memory load on auditory processes, there is a load-dependent reduction of that processing, as manifest in the auditory brainstem responses (ABR) evoked by to-be-ignored clicks. Wave V decreases in amplitude with increases in the visually presented memory load. A visually presented sensory load also produces a load-dependent reduction of a slightly different sort: The sensory load of visually presented information limits the disruptive effects of background sound upon working memory performance. A new early filter model is thus advanced whereby systems within the frontal lobe (affected by sensory or memory load) cholinergically influence top-down corticofugal connections. Those corticofugal connections constrain the processing of complex sounds such as speech at the level of the brainstem. Selective attention thereby limits the distracting effects of background sound entering the higher auditory system via the inferior colliculus. Processing TFS in the brainstem relates to perception of speech under adverse conditions. Attentional selectivity is crucial when the signal heard is degraded or masked: e

  5. Finite element modeling and intravascular ultrasound elastography of vulnerable plaques: parameter variation.

    NARCIS (Netherlands)

    Baldewsing, R.A.; Korte, C.L. de; Schaar, J.A.; Mastik, F.; Steen, A.F.W. van der

    2004-01-01

    BACKGROUND AND GOAL: More than 60% of all myocardial infarction is caused by rupture of a vulnerable plaque. A vulnerable plaque can be described as a large, soft lipid pool covered by a thin fibrous cap. Plaque material composition, geometry, and inflammation caused by infiltration of macrophages

  6. How radiation influences atherosclerotic plaque development. A biophysical approach in ApoE{sup -/-} mice

    Energy Technology Data Exchange (ETDEWEB)

    Kloosterman, Astrid; Dillen, Teun van; Dekkers, Fieke [National Institute for Public Health and the Environment (RIVM), Centre for Environmental Safety and Security, Bilthoven (Netherlands); Bijwaard, Harmen [National Institute for Public Health and the Environment (RIVM), Centre for Environmental Safety and Security, Bilthoven (Netherlands); Inholland University of Applied Sciences, Medical Technology Research Group, Haarlem (Netherlands); Heeneman, Sylvia [Maastricht University Medical Center, Experimental Vascular Pathology group, Department of Pathology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht (Netherlands); Hoving, Saske; Stewart, Fiona A. [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital, Division of Biological Stress Response (H3), Amsterdam (Netherlands)

    2017-11-15

    Atherosclerosis is the development of lipid-laden plaques in arteries and is nowadays considered as an inflammatory disease. It has been shown that high doses of ionizing radiation, as used in radiotherapy, can increase the risk of development or progression of atherosclerosis. To elucidate the effects of radiation on atherosclerosis, we propose a mathematical model to describe radiation-promoted plaque development. This model distinguishes itself from other models by combining plaque initiation and plaque growth, and by incorporating information from biological experiments. It is based on two consecutive processes: a probabilistic dose-dependent plaque initiation process, followed by deterministic plaque growth. As a proof of principle, experimental plaque size data from carotid arteries from irradiated ApoE{sup -/-} mice was used to illustrate how this model can provide insight into the underlying biological processes. This analysis supports the promoting role for radiation in plaque initiation, but the model can easily be extended to include dose-related effects on plaque growth if available experimental data would point in that direction. Moreover, the model could assist in designing future biological experiments on this research topic. Additional biological data such as plaque size data from chronically-irradiated mice or experimental data sets with a larger variety in biological parameters can help to further unravel the influence of radiation on plaque development. To the authors' knowledge, this is the first biophysical model that combines probabilistic and mechanistic modeling which uses experimental data to investigate the influence of radiation on plaque development. (orig.)

  7. 76 FR 66307 - Scientific Information Request on Phototherapy for Treatment of Chronic Plaque Psoriasis

    Science.gov (United States)

    2011-10-26

    ... Information Request on Phototherapy for Treatment of Chronic Plaque Psoriasis AGENCY: Agency for Healthcare... manufacturers of Phototherapy medical devices for treatment of chronic plaque psoriasis. Scientific information... Systemic Agents and Phototherapy for Treatment of Chronic Plaque Psoriasis, which is currently being...

  8. Magnetic resonance imaging of vulnerable atherosclerotic plaques: current imaging strategies and molecular imaging probes

    NARCIS (Netherlands)

    Briley-Saebo, Karen C.; Mulder, Willem J. M.; Mani, Venkatesh; Hyafil, Fabien; Amirbekian, Vardan; Aguinaldo, Juan Gilberto S.; Fisher, Edward A.; Fayad, Zahi A.

    2007-01-01

    The vulnerability or destabilization of atherosclerotic plaques has been directly linked to plaque composition. Imaging modalities, such as magnetic resonance (MR) imaging, that allow for evaluation of plaque composition at a cellular and molecular level, could further improve the detection of

  9. Microglia in diffuse plaques in hereditary cerebral hemorrhage with amyloidosis (Dutch). An immunohistochemical study

    NARCIS (Netherlands)

    Maat-Schieman, M. L.; Rozemuller, A. J.; van Duinen, S. G.; Haan, J.; Eikelenboom, P.; Roos, R. A.

    1994-01-01

    In hereditary cerebral hemorrhage with amyloidosis (Dutch) (HCHWA-D) beta/A4 amyloid deposition is found in meningocortical blood vessels and in diffuse plaques in the cerebral cortex. Diffuse plaques putatively represent early stages in the formation of senile plaques. Microglia are intimately

  10. Stable Size Distribution of Amyloid Plaques Over the Course of Alzheimer Disease

    Science.gov (United States)

    Serrano-Pozo, Alberto; Mielke, Matthew L.; Muzitansky, Alona; Gómez-Isla, Teresa; Growdon, John H.; Bacskai, Brian J.; Betensky, Rebecca A.; Frosch, Matthew P.; Hyman, Bradley T.

    2012-01-01

    Amyloid-β plaques are a key pathological feature of Alzheimer disease (AD), but whether plaque sizes increase or stabilize over the course of AD is unknown. We measured the size distribution of total immunoreactive (10D5-positive) and dense-core (Thioflavine-S-positive) plaques in the temporal neocortex of a large group of AD and plaque-bearing age-matched non-demented subjects to test the hypothesis that amyloid plaques continue to grow along with the progression of the disease. The size of amyloid-β (10D5)-positive plaques did not differ between groups whereas dense-core plaques from the AD group were slightly larger than those in the non-demented group (~25%–30%, p = 0.01). Within the AD group, dense-core plaque size did not independently correlate with duration of clinical disease (from 4 to 21 years, p = 0.68), whereas 10D5-positive plaque size correlated negatively with disease duration (p = 0.01). By contrast, an earlier age of symptom onset strongly predicted a larger postmortem plaque size; this effect was independent of disease duration and the presence of the APOEε4 allele (p = 0.0001). We conclude that plaques vary in size among patients, with larger size distributions correlating with an earlier age of onset, but plaques do not substantially increase in size over the clinical course of the disease. PMID:22805771

  11. Altered carotid plaque signal among different repetition times on T1-weighted magnetic resonance plaque imaging with self-navigated radial-scan technique

    Energy Technology Data Exchange (ETDEWEB)

    Narumi, Shinsuke; Ohba, Hideki; Mori, Kiyofumi; Ohura, Kazumasa; Ono, Ayumi; Terayama, Yasuo [Iwate Medical University, Department of Neurology and Gerontology, Morioka (Japan); Sasaki, Makoto [Iwate Medical University, Advanced Medical Research Center, Morioka (Japan); Ogasawara, Kuniaki [Iwate Medical University, Department of Neurosurgery, Morioka (Japan); Hitomi, Jiro [Iwate Medical University, Department of Anatomy, Morioka (Japan)

    2010-04-15

    Magnetic resonance (MR) plaque imaging for carotid arteries is usually performed by using an electrocardiograph (ECG)-gating technique to eliminate pulsation-related artifacts, which can affect the plaque signals because of varied repetition time (TR) among patients. Hence, we investigated whether differences in TR causes signal alterations of the carotid plaque by using a non-gated plaque imaging technique. We prospectively examined 19 patients with carotid stenosis by using a T1-weighted self-navigated radial-scan technique with TRs of 500, 700, and 900 ms. The signal intensity of the carotid plaque was measured, and the contrast ratio (CR) relative to the adjacent muscle was calculated. CRs of the carotid plaques were 1.39 {+-} 0.39, 1.29 {+-} 0.29, and 1.23 {+-} 0.24 with TRs of 500, 700, and 900 ms, respectively, and were significantly different. Among the plaques, those with a hyperintensity signal (CR > 1.5) and moderate-intensity signal (CR 1.2-1.5) at 500 ms showed a TR-dependent signal decrease (hyperintensity plaques, 1.82 {+-} 0.26; 1.61 {+-} 0.19; and 1.48 {+-} 0.17; moderate-intensity plaques, 1.33 {+-} 0.08; 1.26 {+-} 0.08; and 1.19 {+-} 0.07), while those with an isointensity signal (CR < 1.2) remained unchanged regardless of TR (0.96 {+-} 0.12, 0.96 {+-} 0.11, and 0.97 {+-} 0.13). The signal intensity of the carotid plaque on T1-weighted imaging significantly varies among different TRs and tends to decrease with longer TR. MR plaque imaging with short and constant TR settings that the ECG-gating method cannot realize would be preferable for evaluating plaque characteristics. (orig.)

  12. Plaque-left-behind after brushing: intra-oral reservoir for antibacterial toothpaste ingredients.

    Science.gov (United States)

    Otten, Marieke P T; Busscher, Henk J; Abbas, Frank; van der Mei, Henny C; van Hoogmoed, Chris G

    2012-10-01

    Plaque is never fully removed by brushing and may act as a reservoir for antibacterial ingredients, contributing to their substantive action. This study investigates the contribution of plaque-left-behind and saliva towards substantivity of three antibacterial toothpastes versus a control paste without antibacterial claims. First, volunteers brushed 2 weeks with a control or antibacterial toothpaste. Next, plaque and saliva samples were collected 6 and 12 h after brushing and bacterial concentrations and viabilities were measured. The contributions of plaque and saliva towards substantivity were determined by combining control plaques with experimental plaque or saliva samples and subsequently assessing their viabilities. Bacterial compositions in the various plaque and saliva samples were compared using denaturing gradient gel electrophoresis. The viabilities of plaques after brushing with Colgate-Total® and Crest-Pro-Health® were smaller than of control plaques and up to 12 h after brushing with Crest-Pro-Health® plaques still contained effective, residual antibacterial activity against control plaques. No effective, residual antibacterial activity could be measured in saliva samples after brushing. There was no significant difference in bacterial composition of plaque or saliva after brushing with the different toothpastes. Plaque-left-behind after mechanical cleaning contributes to the substantive action of an antibacterial toothpaste containing stannous fluoride (Crest-Pro-Health®). The absorptive capacity of plaque-left-behind after brushing is of utmost clinical importance, since plaque is predominantly left behind in places where its removal and effective killing matter most. Therewith this study demonstrates a clear and new beneficial effect of the use of antibacterial toothpastes.

  13. Echo-lucency of computerized ultrasound images of carotid atherosclerotic plaques are associated with increased levels of triglyceride-rich lipoproteins as well as increased plaque lipid content

    DEFF Research Database (Denmark)

    Grønholdt, Marie-Louise Moes; Nordestgaard, Børge G.; Weibe, Brit M.

    1998-01-01

    carotid plaque echo-lucency and that echo-lucency predicts a high plaque lipid content. Methods and Results-The study included 137 patients with neurological symptoms and greater than or equal to 50% stenosis of the relevant carotid artery, High-resolution B-mode ultrasound images of carotid plaques were......Background-Echo-lucency of carotid atherosclerotic plaques on computerized ultrasound B-mode images has been associated with a high incidence of brain infarcts as evaluated on CT scans. We tested the hypotheses that triglyceride-rich lipoproteins in the fasting and postprandial state predict...

  14. Echolucency of computerized ultrasound images of carotid atherosclerotic plaques are associated with increased levels of triglyceride-rich lipoproteins as well as increased plaque lipid content

    DEFF Research Database (Denmark)

    Grønholdt, Marie-Louise M.; Nordestgaard, Børge; Wiebe, Britt M.

    1998-01-01

    carotid plaque echo-lucency and that echo-lucency predicts a high plaque lipid content. Methods and Results-The study included 137 patients with neurological symptoms and greater than or equal to 50% stenosis of the relevant carotid artery, High-resolution B-mode ultrasound images of carotid plaques were......Background-Echo-lucency of carotid atherosclerotic plaques on computerized ultrasound B-mode images has been associated with a high incidence of brain infarcts as evaluated on CT scans. We tested the hypotheses that triglyceride-rich lipoproteins in the fasting and postprandial state predict...

  15. 125I eye plaque dose distribution including penumbra characteristics.

    Science.gov (United States)

    de la Zerda, A; Chiu-Tsao, S T; Lin, J; Boulay, L L; Kanna, I; Kim, J H; Tsao, H S

    1996-03-01

    The two main purposes of this work are (1) to determine the penumbra characteristics for 125I eye plaque and the relative influence of the plaque and eye-air interface on the dose distribution, and (2) to initiate development of a treatment planning algorithm for clinical dose calculations. Dose was measured in a newly designed solid water eye phantom for an 125I (6711) seed at the center of a 20 mm COMS eye plaque using thermoluminescent dosimeter (TLD) "cubes" and "minichips" inside and outside the eye, in the longitudinal and transverse central planes. TLD cubes were used in most locations, except for short distances from the seed and in the penumbra region. In the presence of both the plaque and the eye-air interface, the dose along the central axis was found to be reduced by 10% at 1 cm and up to 20% at 2.5 cm, relative to the bulk homogeneous phantom case. In addition, the overall dose reduction was greater for larger off-axis coordinates at a given depth. The penumbra characteristics due to the lip collimation were quantified, particularly the dependence of penumbra center and width on depth. Only small differences were observed between the profiles in the transverse and longitudinal planes. In the bulk geometry (without the eye-air interface), the dose reduction due to the presence of the plaque alone was found to be 7% at a depth of 2.5 cm. The additional reduction of 13% observed, with the presence of eye-air interface (20% combined), can be attributed to the lack of backscattering from the air in front of the eye. The dose-reduction effect due to the anterior air interface alone became unnoticeable at a depth of 1.1 cm (1.5 cm from the eye-air interface). An analytic fit to measured data was developed for clinical dose calculations for a centrally loaded seed. The central axis values of the dose rates multiplied by distance squared, Dr2, were fitted with a double exponential function of depth. The off-axis profile of Dr2, at a given depth, was

  16. Brainstem projections of neurons located in various subdivisions of the dorsolateral hypothalamic area – an anterograde tract-tracing study

    Directory of Open Access Journals (Sweden)

    Rege Sugárka Papp

    2014-05-01

    Full Text Available The projections from the dorsolateral hypothalamic area (DLH to the lower brainstem have been investigated by using biotinylated dextran amine (BDA, an anterograde tracer in rats. The DLH can be divided into 3 areas (dorsomedial hypothalamus, perifornical area, lateral hypothalamic area, and further subdivided into 8 subdivisions. After unilateral stereotaxic injections of BDA into individual DLH subdivisions, the correct sites of injections were controlled histologically, and the distribution patterns of BDA-positive fibers were mapped on serial sections between the hypothalamus and spinal cord in 22 rats. BDA-labeled fibers were observable over 100 different brainstem areas, nuclei or subdivisions. Injections into the 8 DLH subdivisions established distinct topographical patterns. In general, the density of labeled fibers was low in the lower brainstem. High density of fibers was seen only 4 of the 116 areas: in the lateral and ventrolateral parts of the periaqueductal gray, the Barrington’s and the pedunculopontine tegmental nuclei. All of the biogenic amine cell groups in the lower brainstem (9 noradrenaline, 3 adrenaline and 9 serotonin cell groups received labeled fibers, some of them from all, or at least 7 DLH subdivisions, mainly from perifornical and ventral lateral hypothalamic neurons. Some of the tegmental nuclei and nuclei of the reticular formation were widely innervated, although the density of the BDA-labeled fibers was generally low. No definitive descending BDA-positive pathway, but long-run solitaire BDA-labeled fibers were seen in the lower brainstem. These descending fibers joined some of the large tracts or fasciculi in the brainstem. The distribution pattern of BDA-positive fibers of DLH origin throughout the lower brainstem was comparable to patterns of previously published orexin- or melanin-concentrating hormone-immunoreactive fibers with somewhat differences.

  17. Monte Carlo Estimation of Absorbed Dose Distributions Obtained from Heterogeneous 106Ru Eye Plaques.

    Science.gov (United States)

    Zaragoza, Francisco J; Eichmann, Marion; Flühs, Dirk; Sauerwein, Wolfgang; Brualla, Lorenzo

    2017-09-01

    The distribution of the emitter substance in 106 Ru eye plaques is usually assumed to be homogeneous for treatment planning purposes. However, this distribution is never homogeneous, and it widely differs from plaque to plaque due to manufacturing factors. By Monte Carlo simulation of radiation transport, we study the absorbed dose distribution obtained from the specific CCA1364 and CCB1256 106 Ru plaques, whose actual emitter distributions were measured. The idealized, homogeneous CCA and CCB plaques are also simulated. The largest discrepancy in depth dose distribution observed between the heterogeneous and the homogeneous plaques was 7.9 and 23.7% for the CCA and CCB plaques, respectively. In terms of isodose lines, the line referring to 100% of the reference dose penetrates 0.2 and 1.8 mm deeper in the case of heterogeneous CCA and CCB plaques, respectively, with respect to the homogeneous counterpart. The observed differences in absorbed dose distributions obtained from heterogeneous and homogeneous plaques are clinically irrelevant if the plaques are used with a lateral safety margin of at least 2 mm. However, these differences may be relevant if the plaques are used in eccentric positioning.

  18. High shear stress relates to intraplaque haemorrhage in asymptomatic carotid plaques

    DEFF Research Database (Denmark)

    Tuenter, A.; Selwaness, M.; Arias Lorza, A.

    2016-01-01

    estimating equations analysis, adjusting for age, sex and carotid wall thickness. RESULTS: The study group consisted of 93 atherosclerotic carotid arteries of 74 participants. In plaques with higher maximum shear stresses, IPH was more often present (OR per unit increase in maximum shear stress (log......BACKGROUND AND AIMS: Carotid artery plaques with vulnerable plaque components are related to a higher risk of cerebrovascular accidents. It is unknown which factors drive vulnerable plaque development. Shear stress, the frictional force of blood at the vessel wall, is known to influence plaque...... formation. We evaluated the association between shear stress and plaque components (intraplaque haemorrhage (IPH), lipid rich necrotic core (LRNC) and/or calcifications) in relatively small carotid artery plaques in asymptomatic persons. METHODS: Participants (n = 74) from the population-based Rotterdam...

  19. Quantification of atherosclerotic plaque activity and vascular inflammation using [18-F] fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT).

    Science.gov (United States)

    Mehta, Nehal N; Torigian, Drew A; Gelfand, Joel M; Saboury, Babak; Alavi, Abass

    2012-05-02

    Conventional non-invasive imaging modalities of atherosclerosis such as coronary artery calcium (CAC) and carotid intimal medial thickness (C-IMT) provide information about the burden of disease. However, despite multiple validation studies of CAC, and C-IMT, these modalities do not accurately assess plaque characteristics, and the composition and inflammatory state of the plaque determine its stability and, therefore, the risk of clinical events. [(18)F]-2-fluoro-2-deoxy-D-glucose (FDG) imaging using positron-emission tomography (PET)/computed tomography (CT) has been extensively studied in oncologic metabolism. Studies using animal models and immunohistochemistry in humans show that FDG-PET/CT is exquisitely sensitive for detecting macrophage activity, an important source of cellular inflammation in vessel walls. More recently, we and others have shown that FDG-PET/CT enables highly precise, novel measurements of inflammatory activity of activity of atherosclerotic plaques in large and medium-sized arteries. FDG-PET/CT studies have many advantages over other imaging modalities: 1) high contrast resolution; 2) quantification of plaque volume and metabolic activity allowing for multi-modal atherosclerotic plaque quantification; 3) dynamic, real-time, in vivo imaging; 4) minimal operator dependence. Finally, vascular inflammation detected by FDG-PET/CT has been shown to predict cardiovascular (CV) events independent of traditional risk factors and is also highly associated with overall burden of atherosclerosis. Plaque activity by FDG-PET/CT is modulated by known beneficial CV interventions such as short term (12 week) statin therapy as well as longer term therapeutic lifestyle changes (16 months). The current methodology for quantification of FDG uptake in atherosclerotic plaque involves measurement of the standardized uptake value (SUV) of an artery of interest and of the venous blood pool in order to calculate a target to background ratio (TBR), which is

  20. Inhibition of dental plaque formation by toothpaste containing propolis

    Directory of Open Access Journals (Sweden)

    Nurin Aisyiyah Listyasari

    2012-12-01

    Full Text Available Background: Plaque is the main cause of caries and periodontal disease. Caries and periodontal disease can be prevented by inhibiting dental plaque formation. To inhibit the formation of plaque, teeth must be brushed with toothpaste. According to previous studies, propolis contains apigenin and tt-farnesol classified as flavonoid that can inhibit the formation of dental plaque by inhibiting glucosyltransferase enzym and membrane integrity of Streptococcus mutans. Purpose: The aim of this study was to determine the effect of toothpaste containing propolis on the formation of dental plaque. Methods: Post test with only control group design was used. The subjects of this study were 30 boarding school students of Hidayatullah, Yayasan Al-Burhan, Gedawang, Semarang, divided into two groups, randomized control group and treatment group. Control group was not treated with toothpaste contanining propolis. Meanwhile, treatment group was treated with toothpaste containing propolis. Plaque then was measured by using plaque index of Sillness and Loe method after using toothpaste containing propolis for four hours. Afterwards, the data was analyzed by a computer program, Mann-Whitney test, with its significance p < 0.05. Results: The result of Mann-Whitney test showed a significant difference, 0.002 (p < 0.05, between the control group and the treatment group. The median of the control group was about 3.41, while that of the treatment group was about 0.58. Conclusion: The use of toothpaste contaning propolis can prevent dental plaque formation.Latar belakang: Plak merupakan penyebab utama terjadinya karies dan penyakit periodontal. Karies dan penyakit periodontal dapat dicegah dengan menghambat pembentukan plak gigi. Untuk mencegah terbentuknya plak, gigi harus digosok menggunakan pasta gigi. Penelitian terdahulu menyebutkan bahwa propolis mengandung flavonoid apigenin dan tt-farnesol yang mampu menghambat aktivitas enzim glukosiltransferase dan menghambat

  1. Gene expression and 18FDG uptake in atherosclerotic carotid plaques

    DEFF Research Database (Denmark)

    Pedersen, Sune Folke; Graebe, Martin; Fisker Hag, Anne Mette

    2010-01-01

    ) and an additional ipsilateral internal carotid artery stenosis of greater than 60% were recruited. FDG uptake in the carotids was determined by PET/computed tomography and expressed as mean and maximal standardized uptake values (SUVmean and SUVmax). The atherosclerotic plaques were subsequently recovered...... by carotid endarterectomy. The gene expression of markers of vulnerability - CD68, IL-18, matrix metalloproteinase 9, cathepsin K, GLUT-1, and hexokinase type II (HK2) - were measured in plaques by quantitative PCR. RESULTS: In a multivariate linear regression model, GLUT-1, CD68, cathepsin K, and HK2 gene...... expression remained in the final model as predictive variables of FDG accumulation calculated as SUVmean (R=0.26, PK, and HK2 gene expression as independent predictive variables of FDG accumulation calculated...

  2. Microbiologic aspects of dental plaque and dental caries.

    Science.gov (United States)

    Marsh, P D

    1999-10-01

    Dental plaque is an example of a microbial biofilm with a diverse microbial composition; it is found naturally on teeth and confers advantages to the host, for example, by preventing colonization by exogenous, and often pathogenic, micro-organisms. In individuals with a high frequency sugar diet, or with a severely compromised saliva flow, the levels of potentially cariogenic bacteria (acid-producing and acid-tolerating species) can increase beyond those compatible with enamel health. This article discusses antimicrobial strategies to control dental caries, including; reducing plaque levels, in general or specific cariogenic bacteria in particular, by antiplaque or antimicrobial agents; reducing bacterial acid production by replacing fermentable carbohydrates in the diet with sugar substitutes, or by interfering with bacterial metabolism with fluoride or antimicrobial agents.

  3. Choroidal sclerosis in localized scleroderma (morphea en plaque).

    Science.gov (United States)

    Milenkovic, S; Petrovic, L; Risimic, D; Kosanovic-Jakovic, N; Jaksic, V; Djakovic, Z; Stojkovic, M; Risovic, D; Ivankovic, Lj; Ivancevic-Milenkovic, M

    2008-01-01

    Plaque morphea is a superficial type of morphea (localized scleroderma) which is characterized by various fibrotic areas of the dermis without systemic features. We present a 63-year-old man with morphea en plaque. The skin on his forearms and feet was taut, thickened and hidebound with scattered telangiectatic changes. Autoantibody profile was obtained and only ANA were positive (1:80). The patient had a decreased vision in the only functional, left eye. Our case is specific because the patient negated any kind of health problem, meaning the morphea and visual deterioration were of outstanding importance for him. Choroidal sclerosis and fundus appearance was extremely impressive and, to our knowledge, this is the first report of such unique case of ocular involvement in the literature. (c) 2008 S. Karger AG, Basel

  4. Apollo 11 Commander Armstrong Presents President With Commemorative Plaque

    Science.gov (United States)

    1974-01-01

    On June 4, 1974, 5 years after the successful Apollo 11 lunar landing mission, commander Neil Armstrong (right) presented a plaque to U.S. President Richard Milhous Nixon (left) on behalf of all people who had taken part in the space program. In making the presentation, Armstrong said 'Mr. President, you have proclaimed this week to be United States Space week in conjunction with the fifth anniversary of our first successful landing on the Moon. It is my privilege to represent my colleagues, the crewmen of projects Mercury, Gemini, Apollo, and Skylab, and the men and women of NASA, and the hundreds of thousands of Americans from across the land who contributed so mightily to the success of our efforts in space in presenting this plaque which bears the names of each individual who has had the privilege of representing this country' in a space flight. The presentation was made at the California white house in San Clemente.

  5. Nonlinear registration of serial coronary CT angiography (CCTA) for assessment of changes in atherosclerotic plaque

    International Nuclear Information System (INIS)

    Woo, Jonghye; Dey, Damini; Cheng, Victor Y.; Hong, Byung-Woo; Ramesh, Amit; Sundaramoorthi, Ganesh; Nakazato, Ryo; Berman, Daniel S.; Germano, Guido; Kuo, C.-C. Jay; Slomka, Piotr J.

    2010-01-01

    Purpose: Coronary CT angiography (CCTA) is a high-resolution three-dimensional imaging technique for the evaluation of coronary arteries in suspected or confirmed coronary artery disease (CAD). Coregistration of serial CCTA scans would allow precise superimposition of images obtained at two different points in time, which could aid in recognition of subtle changes and precise monitoring of coronary plaque progression or regression. To this end, the authors aimed at developing a fully automatic nonlinear volume coregistration for longitudinal CCTA scan pairs. Methods: The algorithm combines global displacement and local deformation using nonlinear volume coregistration with a volume-preserving constraint. Histogram matching of intensities between two serial scans is performed prior to nonlinear coregistration with dense nonparametric local deformation in which sum of squared differences is used as a similarity measure. The approximate segmentation of coronary arteries obtained from commercially available software provides initial anatomical landmarks for the coregistration algorithm that help localize and emphasize the structure of interest. To avoid possible bias caused by incorrect segmentation, the authors convolve the Gaussian kernel with the segmented binary coronary tree mask and define an extended weighted region of interest. A multiresolution approach is employed to represent coarse-to-fine details of both volumes and the energy function is optimized using a gradient descent method. The authors applied the algorithm in ten paired CCTA datasets (20 scans in total) obtained within 10.7±5.7 months from each other on a dual source CT scanner to monitor progression of CAD. Results: Serial CCTA coregistration was successful in 9/10 cases as visually confirmed. The global displacement and local deformation of target registration error obtained from four anatomical landmarks were 2.22±1.15 and 1.56±0.74 mm, respectively, and the inverse consistency error of local

  6. Morphological classification of mobile plaques and their association with early recurrence of stroke.

    Science.gov (United States)

    Ogata, Toshiyasu; Yasaka, Masahiro; Wakugawa, Yoshiyuki; Kitazono, Takanari; Okada, Yasushi

    2010-01-01

    The present study investigated the frequency and morphological characteristics of carotid mobile plaques and examined the relationship between carotid mobile plaques and recurrent strokes. The study included 94 consecutive acute stroke patients with large-artery atherosclerosis associated with extracranial carotid stenosis. We investigated the presence of mobile plaques by carotid ultrasonography and classified patients into two groups (mobile group and non-mobile group). We compared backgrounds, MRI and ultrasonographic findings, neurological severity on admission and at discharge, and the rate of early recurrent stroke between both groups. Mobile plaques were detected in 12 patients (12.8%). There were four types of mobile plaques: (1) the jellyfish-type plaque, in which the fibrous cap fluctuated like a jellyfish; (2) the streaming-band-type plaque, in which the string attached to the plaque was swaying; (3) the mobile-thrombus-type plaque, in which a mobile mass was attached to the plaque surface, and (4) the fluctuating-ulcer-type plaque, which contained a mobile substance in the plaque ulcer. Although National Institutes of Health Stroke Scale (NIHSS) scores on admission were less severe in the mobile group than in the non-mobile group (median 1 vs. 4, respectively; p = 0.004), the rate of early recurrent stroke was significantly higher in the mobile group than in the non-mobile group (33.3 vs. 7.3%, respectively; p = 0.022). There were no significant differences in NIHSS scores at discharge between groups. Morphologically, several types of mobile plaques were detected in consecutive patients with acute stroke associated with carotid stenosis. Mobile plaques are strongly associated with an early recurrence of stroke. Copyright © 2010 S. Karger AG, Basel.

  7. Dynamics of red fluorescent dental plaque during experimental gingivitis--A cohort study.

    Science.gov (United States)

    van der Veen, Monique H; Volgenant, Catherine M C; Keijser, Bart; Ten Cate, Jacob Bob M; Crielaard, Wim

    2016-05-01

    The dynamics of red fluorescent plaque (RFP) in comparison to clinical plaque and bleeding scores were studied during an experimental gingivitis protocol in a cohort of healthy participants. Forty-one participants were monitored for RFP before (24h plaque), during 14 days plaque accumulation (days 2, 5, 9, 14) and after 7 days recovery (24h plaque). RFP was assessed on fluorescence photographs of the vestibular aspect of the anterior teeth (cuspid to cuspid) in the upper and lower jaw. Clinical plaque and bleeding were assessed at days -14, 0, 14 and 21. RFP of 24h plaque was reproducible (days -14, 0), then increased during 14 days plaque accumulation and returned to baseline after 7 days recovery. Groups of low, moderate and high RFP formers were statistically significantly different at all times even already at baseline. The individual RFP response during 14 days plaque accumulation correlated well with RFP of 24h plaque (days -14, 0). RFP correlated moderate to well with clinical plaque at days -14, 0, 14 and 21. From day 2 of the gingivitis challenge RFP correlated with bleeding at day 14. RFP provided an objective measure of oral hygiene status. Given the correlation with clinical parameters found, the amount of RFP after 24h plaque accumulation was indicatory for the inflammatory response during a prolonged period of no oral hygiene. This trial was registered at the public trial register ​of the Central Committee on Research Involving Human Subjects (CCMO) under number NL51111.029.14 CLINICAL SIGNIFICANCE: This paper shows the association between RFP after 24h plaque accumulation and inflammatory response after a prolonged period of no oral hygiene. Red plaque fluorescence can be used to identify subjects at risk for developing gingival inflammation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Evaluation of the early enhancement of coronary atherosclerotic plaque by contrast-enhanced MR angiography

    Energy Technology Data Exchange (ETDEWEB)

    Li Tao [Department of Radiology, The General Hospital of Chinese People' s Armed Police Forces, Number 69, Yong Ding Road, Hai Dian District, Beijing (China); Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China); Zhao Xihai [Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China); Liu Xin [Paul C. Lauterbur Biomedical Imaging Center, Institute of Biomedical and Health Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Science, Shenzhen 518067 (China); Gao Jianhua [Department of Radiology, The General Hospital of Chinese People' s Armed Police Forces, Number 69, Yong Ding Road, Hai Dian District, Beijing (China); Zhao Shaohong [Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China); Li Xin; Zhou Weihua [Department of Radiology, The General Hospital of Chinese People' s Armed Police Forces, Number 69, Yong Ding Road, Hai Dian District, Beijing (China); Cai Zulong [Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China); Zhang Weiguo [Cardiovascular and Neurological Consulting Institute, 6771 San Fernando, Irving, TX 75039 (United States); Yang Li, E-mail: Yangli301@yahoo.com [Department of Radiology, Chinese People' s Liberation Army General Hospital, Number 28, Fu Xing Road, Hai Dian District, Beijing (China)

    2011-10-15

    Purpose: To evaluate the early enhancement of coronary atherosclerotic plaque using contrast-enhanced MR angiography (CE-MRA) and investigate the association between unstable angina pectoris (UAP) and early enhancement of the plaque. Methods: Forty-one patients presenting with angina pectoris and demonstrating single-vessel disease with non-calcified plaque and significant coronary stenosis ({>=}50%) on CTA were consecutively recruited for coronary CE-MRA. Contrast-to-noise ratio of the culprit plaque guided by CTA was measured on a cross-sectional multi-planar reconstruction image of the plaque on both pre- and post-CE-MRA. A 50% increasing of CNR was defined as plaque enhancement. The association between early enhancement of the plaques and UAP was analyzed. Results: Thirty-seven non-calcified plaques with significant coronary stenosis were detected in the 37 patients on MRA. 4 subjects were excluded because coronary atherosclerotic plaques were inadequate for identification on MRA. Of the 37 patients, 18 patients had UAP and other 19 patients presented stable angina pectoris (SAP). Of the 37 plaques on CE-MRA, 13 and 24 plaques presented early enhancement and no enhancement, respectively. Of the 13 early-enhanced plaques, 11 (85%) and 2 (15%) were found in the patients with UAP and SAP, respectively (p < 0.01). Of the 37 patients, 11 (61%) with UAP and 2 (11%) with SAP had early-enhanced plaques, respectively (p < 0.01). Conclusion: CE-MRA allows detection of early enhancement of coronary atherosclerotic plaque. The early enhancement is common in unstable angina and could be a sign of vulnerability.

  9. Hydrocortisone supresses inflammatory activity of metalloproteinase - 8 in carotid plaque

    Science.gov (United States)

    Gabriel, Sthefano Atique; Antonangelo, Leila; Capelozzi, Vera Luiza; Beteli, Camila Baumann; de Camargo Júnior, Otacílio; de Aquino, José Luis Braga; Caffaro, Roberto Augusto

    2015-01-01

    Objective Matrix metalloproteinases are inflammatory biomarkers involved in carotid plaque instability. Our objective was to analyze the inflammatory activity of plasma and carotid plaque MMP-8 and MMP-9 after intravenous administration of hydrocortisone. Methods The study included 22 patients with stenosis ≥ 70% in the carotid artery (11 symptomatic and 11 asymptomatic) who underwent carotid endarterectomy. The patients were divided into two groups: Control Group - hydrocortisone was not administered, and Group 1 - 500 mg intravenous hydrocortisone was administered during anesthetic induction. Plasma levels of MMP-8 and MMP-9 were measured preoperatively (24 hours before carotid endarterectomy) and at 1 hour, 6 hours and 24 hours after carotid endarterectomy. In carotid plaque, tissue levels of MMP-8 and MMP-9 were measured. Results Group 1 showed increased serum levels of MMP- 8 (994.28 pg/ml and 408.54 pg/ml, respectively; P=0.045) and MMP-9 (106,656.34 and 42,807.69 respectively; P=0.014) at 1 hour after carotid endarterectomy compared to the control group. Symptomatic patients in Group 1 exhibited lower tissue concentration of MMP-8 in comparison to the control group (143.89 pg/ml and 1317.36 respectively; P=0.003). There was a correlation between preoperative MMP-9 levels and tissue concentrations of MMP-8 (P=0.042) and MMP-9 (P=0.019) between symptomatic patients in the control group. Conclusion Hydrocortisone reduces the concentration of MMP- 8 in carotid plaque, especially in symptomatic patients. There was an association between systemic and tissue inflammation. PMID:26313719

  10. Ichthyosiform large plaque parapsoriasis: Report of a rare entity

    Directory of Open Access Journals (Sweden)

    Falguni Nag

    2013-01-01

    Full Text Available Large plaque parapsoriasis (LPP is an idiopathic, chronic scaly dermatosis classified within parapsoriasis group of diseases, occurring commonly in middle aged patients of all races and geographic regions. LPP and its variants are closely related to the patch stage of mycosis fungoides. The two types of LPP mostly described are the poikilodermatous and retiform parapsoriasis. We are reporting an ichthyosiform LPP for its rarity.

  11. Acute and chronic craniofacial pain: brainstem mechanisms of nociceptive transmission and neuroplasticity, and their clinical correlates.

    Science.gov (United States)

    Sessle, B J

    2000-01-01

    This paper reviews the recent advances in knowledge of brainstem mechanisms related to craniofacial pain. It also draws attention to their clinical implications, and concludes with a brief overview and suggestions for future research directions. It first describes the general organizational features of the trigeminal brainstem sensory nuclear complex (VBSNC), including its input and output properties and intrinsic characteristics that are commensurate with its strategic role as the major brainstem relay of many types of somatosensory information derived from the face and mouth. The VBSNC plays a crucial role in craniofacial nociceptive transmission, as evidenced by clinical, behavioral, morphological, and electrophysiological data that have been especially derived from studies of the relay of cutaneous nociceptive afferent inputs through the subnucleus caudalis of the VBSNC. The recent literature, however, indicates that some fundamental differences exist in the processing of cutaneous vs. other craniofacial nociceptive inputs to the VBSNC, and that rostral components of the VBSNC may also play important roles in some of these processes. Modulatory mechanisms are also highlighted, including the neurochemical substrate by which nociceptive transmission in the VBSNC can be modulated. In addition, the long-term consequences of peripheral injury and inflammation and, in particular, the neuroplastic changes that can be induced in the VBSNC are emphasized in view of the likely role that central sensitization, as well as peripheral sensitization, can play in acute and chronic pain. The recent findings also provide new insights into craniofacial pain behavior and are particularly relevant to many approaches currently in use for the management of pain and to the development of new diagnostic and therapeutic procedures aimed at manipulating peripheral inputs and central processes underlying nociceptive transmission and its control within the VBSNC.

  12. Diffuse and focal presentations of brainstem tumors in children: the images and the prognostic value

    International Nuclear Information System (INIS)

    Menor, F.; Canete, A.; Romero, M. J.; Trilles, L.; Carvajal, E.; Marti-Bonmati, L.

    2000-01-01

    To determine whether the presentation of brainstem tumors as diffuse or focal lesions showed any prognostic value in children. A retrospective review was carried out of the neuroradiological findings in 43 children with brainstem tumors, all of whom underwent computed tomography (CT) and 31 of whom underwent magnetic resonance (MR). The diffuse tumors (n=20) were all located in the pons, spreading to mesencephalon in 6 cases and to medulla oblongata in 1, and exhibiting exophytic growth, preferentially to the prepontine cistern. They presented homogeneous low attenuation in CT (90%) and decrease/increased signal intensity in T1/T2-weighted MR images (91.6%). Contrast uptake was observed in 20% of cases, with agreement between CT and MR. The patients showed a good initial response to treatment (70%), a high rate of relapse (80%) and a 5-year survival of 12%. The focal tumors were located in the pons (11 cases, spreading to the medulla oblongata in 2), mesencephalon (11 cases, 9 tectal and 2 peduncular) and medulla oblongata (1 case), and exhibited exophytic growth predominantly to the pontocerebellar junction and to the cerebellar peduncles. They showed a certain tendency toward heterogeneity (21.7%), toward isoattenuation in CT (47.8%) and isointensity in T1-weighted MR images (26.3%). CT showed a rate of tumor uptake of 26%, while the rate of contrast iptake was 58% MR. Fifty percent of these lesions responded well to therapy, with a recurrence rate of 28% and 4-year survival of 63%. Neuroimaging helps to define two basic patterns in brainstem tumors that play a role in prognosis. The diffuse tumor, which characteristically shows a good initial response to therapy, has a worse prognosis, probably reflecting its histological aggressiveness. (Author) 21 refs

  13. Cortical and brainstem plasticity in Tourette syndrome and obsessive-compulsive disorder.

    Science.gov (United States)

    Suppa, Antonio; Marsili, Luca; Di Stasio, Flavio; Berardelli, Isabella; Roselli, Valentina; Pasquini, Massimo; Cardona, Francesco; Berardelli, Alfredo

    2014-10-01

    Gilles de la Tourette syndrome is characterized by motor/vocal tics commonly associated with psychiatric disorders, including obsessive-compulsive disorder. We investigated primary motor cortex and brainstem plasticity in Tourette patients, exposed and unexposed to chronic drug treatment, with and without psychiatric disturbances. We also investigated primary motor cortex and brainstem plasticity in obsessive-compulsive disorder. We studied 20 Tourette patients with and without psychiatric disturbances, 15 with obsessive-compulsive disorder, and 20 healthy subjects. All groups included drug-naïve patients. We conditioned the left primary motor cortex with intermittent/continuous theta-burst stimulation and recorded motor evoked potentials. We conditioned the supraorbital nerve with facilitatory/inhibitory high-frequency stimulation and recorded the blink reflex late response area. In healthy subjects, intermittent theta-burst increased and continuous theta-burst stimulation decreased motor evoked potentials. Differently, intermittent theta-burst failed to increase and continuous theta-burst stimulation failed to decrease motor evoked potentials in Tourette patients, with and without psychiatric disturbances. In obsessive-compulsive disorder, intermittent/continuous theta-burst stimulation elicited normal responses. In healthy subjects and in subjects with obsessive-compulsive disorder, the blink reflex late response area increased after facilitatory high-frequency and decreased after inhibitory high-frequency stimulation. Conversely, in Tourette patients, with and without psychiatric disturbances, facilitatory/inhibitory high-frequency stimulation left the blink reflex late response area unchanged. Theta-burst and high-frequency stimulation elicited similar responses in drug-naïve and chronically treated patients. Tourette patients have reduced plasticity regardless of psychiatric disturbances. These findings suggest that abnormal plasticity contributes to the

  14. DESCRIPTION OF BRAINSTEM AUDITORY EVOKED RESPONSES (AIR AND BONE CONDUCTION IN CHILDREN WITH NORMAL HEARING

    Directory of Open Access Journals (Sweden)

    A. V. Pashkov

    2014-01-01

    Full Text Available Diagnosis of hearing level in small children with conductive hearing loss associated with congenital craniofacial abnormalities, particularly with agenesis of external ear and external auditory meatus is a pressing issue. Conventional methods of assessing hearing in the first years of life, i. e. registration of brainstem auditory evoked responses to acoustic stimuli in the event of air conduction, does not give an indication of the auditory analyzer’s condition due to potential conductive hearing loss in these patients. This study was aimed at assessing potential of diagnosing the auditory analyzer’s function with registering brainstem auditory evoked responses (BAERs to acoustic stimuli transmitted by means of a bone vibrator. The study involved 17 children aged 3–10 years with normal hearing. We compared parameters of registering brainstem auditory evoked responses (peak V depending on the type of stimulus transmission (air/bone in children with normal hearing. The data on thresholds of the BAERs registered to acoustic stimuli in the event of air and bone conduction obtained in this study are comparable; hearing thresholds in the event of acoustic stimulation by means of a bone vibrator correlates with the results of the BAERs registered to the stimuli transmitted by means of air conduction earphones (r = 0.9. High correlation of thresholds of BAERs to the stimuli transmitted by means of a bone vibrator with thresholds of BAERs registered when air conduction earphones were used helps to assess auditory analyzer’s condition in patients with any form of conductive hearing loss.  

  15. Erythropoietin and its receptors in the brainstem of adults with fatal falciparum malaria

    Directory of Open Access Journals (Sweden)

    White Nicholas J

    2009-11-01

    Full Text Available Abstract Background Facilitation of endogenous neuroprotective pathways, such as the erythropoietin (Epo pathway, has been proposed as adjuvant treatment strategies in cerebral malaria. Whether different endogenous protein expression levels of Epo or differences in the abundance of its receptor components could account for the extent of structural neuropathological changes or neurological complications in adults with severe malaria was investigated. Methods High sensitivity immunohistochemistry was used to assess the frequency, distribution and concordance of Epo and components of its homodimeric and heteromeric receptors, Epo receptor and CD131, within the brainstem of adults who died of severe malaria. The following relationships with Epo and its receptor components were also defined: (i sequestration and indicators of hypoxia; (ii vascular damage in the form of plasma protein leakage and haemorrhage; (iii clinical complications and neuropathological features of severe malaria disease. Brainstems of patients dying in the UK from unrelated non-infectious causes were examined for comparison. Results The incidence of endogenous Epo in parenchymal brain cells did not greatly differ between severe malaria and non-neurological UK controls at the time of death. However, EpoR and CD131 labelling of neurons was greater in severe malaria compared with non-neurological controls (P = .009. EpoR labelling of vessels was positively correlated with admission peripheral parasite count (P = .01 and cerebral sequestration (P P = .001. There were no significant correlations with indicators of vascular damage, neuronal chromatolysis, axonal swelling or vital organ failure. Conclusion Cells within the brainstem of severe malaria patients showed protein expression of Epo and its receptor components. However, the incidence of endogeneous expression did not reflect protection from vascular or neuronal injury, and/or clinical manifestations, such as coma. These

  16. Convergent input from brainstem coincidence detectors onto delay-sensitive neurons in the inferior colliculus.

    Science.gov (United States)

    McAlpine, D; Jiang, D; Shackleton, T M; Palmer, A R

    1998-08-01

    Responses of low-frequency neurons in the inferior colliculus (IC) of anesthetized guinea pigs were studied with binaural beats to assess their mean best interaural phase (BP) to a range of stimulating frequencies. Phase plots (stimulating frequency vs BP) were produced, from which measures of characteristic delay (CD) and characteristic phase (CP) for each neuron were obtained. The CD provides an estimate of the difference in travel time from each ear to coincidence-detector neurons in the brainstem. The CP indicates the mechanism underpinning the coincidence detector responses. A linear phase plot indicates a single, constant delay between the coincidence-detector inputs from the two ears. In more than half (54 of 90) of the neurons, the phase plot was not linear. We hypothesized that neurons with nonlinear phase plots received convergent input from brainstem coincidence detectors with different CDs. Presentation of a second tone with a fixed, unfavorable delay suppressed the response of one input, linearizing the phase plot and revealing other inputs to be relatively simple coincidence detectors. For some neurons with highly complex phase plots, the suppressor tone altered BP values, but did not resolve the nature of the inputs. For neurons with linear phase plots, the suppressor tone either completely abolished their responses or reduced their discharge rate with no change in BP. By selectively suppressing inputs with a second tone, we are able to reveal the nature of underlying binaural inputs to IC neurons, confirming the hypothesis that the complex phase plots of many IC neurons are a result of convergence from simple brainstem coincidence detectors.

  17. Chronic exposure to hypergravity affects thyrotropin-releasing hormone levels in rat brainstem and cerebellum

    Science.gov (United States)

    Daunton, N. G.; Tang, F.; Corcoran, M. L.; Fox, R. A.; Man, S. Y.

    1998-01-01

    In studies to determine the neurochemical mechanisms underlying adaptation to altered gravity we have investigated changes in neuropeptide levels in brainstem, cerebellum, hypothalamus, striatum, hippocampus, and cerebral cortex by radioimmunoassay. Fourteen days of hypergravity (hyperG) exposure resulted in significant increases in thyrotropin-releasing hormone (TRH) content of brainstem and cerebellum, but no changes in levels of other neuropeptides (beta-endorphin, cholecystokinin, met-enkephalin, somatostatin, and substance P) examined in these areas were found, nor were TRH levels significantly changed in any other brain regions investigated. The increase in TRH in brainstem and cerebellum was not seen in animals exposed only to the rotational component of centrifugation, suggesting that this increase was elicited by the alteration in the gravitational environment. The only other neuropeptide affected by chronic hyperG exposure was met-enkephalin, which was significantly decreased in the cerebral cortex. However, this alteration in met-enkephalin was found in both hyperG and rotation control animals and thus may be due to the rotational rather than the hyperG component of centrifugation. Thus it does not appear as if there is a generalized neuropeptide response to chronic hyperG following 2 weeks of exposure. Rather, there is an increase only of TRH and that occurs only in areas of the brain known to be heavily involved with vestibular inputs and motor control (both voluntary and autonomic). These results suggest that TRH may play a role in adaptation to altered gravity as it does in adaptation to altered vestibular input following labyrinthectomy, and in cerebellar and vestibular control of locomotion, as seen in studies of ataxia.

  18. Enterovirus 71 can directly infect the brainstem via cranial nerves and infection can be ameliorated by passive immunization.

    Science.gov (United States)

    Tan, Soon Hao; Ong, Kien Chai; Wong, Kum Thong

    2014-11-01

    Enterovirus 71 (EV71)-associated hand, foot, and mouth disease may be complicated by encephalomyelitis. We investigated EV71 brainstem infection and whether this infection could be ameliorated by passive immunization in a mouse model. Enterovirus 71 was injected into unilateral jaw/facial muscles of 2-week-old mice, and hyperimmune sera were given before or after infection. Harvested tissues were studied by light microscopy, immunohistochemistry, in situ hybridization, and viral titration. In unimmunized mice, viral antigen and RNA were detected within 24 hours after infection only in ipsilateral cranial nerves, motor trigeminal nucleus, reticular formation, and facial nucleus; viral titers were significantly higher in the brainstem than in the spinal cord samples. Mice given preinfection hyperimmune serum showed a marked reduction of ipsilateral viral antigen/RNA and viral titers in the brainstem in a dose-dependent manner. With optimum hyperimmune serum given after infection, brainstem infection was significantly reduced in a time-dependent manner. A delay in disease onset and a reduction of disease severity and mortality were also observed. Thus, EV71 can directly infect the brainstem, including the medulla, via cranial nerves, most likely by retrograde axonal transport. This may explain the sudden cardiorespiratory collapse in human patients with fatal encephalomyelitis. Moreover, our results suggest that passive immunization may still benefit EV71-infected patients who have neurologic complications.

  19. Sortilin Fragments Deposit at Senile Plaques in Human Cerebrum

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    Xia Hu

    2017-06-01

    Full Text Available Genetic variations in the vacuolar protein sorting 10 protein (Vps10p family have been linked to Alzheimer’s disease (AD. Here we demonstrate deposition of fragments from the Vps10p member sortilin at senile plaques (SPs in aged and AD human cerebrum. Sortilin changes were characterized in postmortem brains with antibodies against the extracellular and intracellular C-terminal domains. The two antibodies exhibited identical labeling in normal human cerebrum, occurring in the somata and dendrites of cortical and hippocampal neurons. The C-terminal antibody also marked extracellular lesions in some aged and all AD cases, appearing as isolated fibrils, mini-plaques, dense-packing or circular mature-looking plaques. Sortilin and β-amyloid (Aβ deposition were correlated overtly in a region/lamina- and case-dependent manner as analyzed in the temporal lobe structures, with co-localized immunofluorescence seen at individual SPs. However, sortilin deposition rarely occurred around the pia, at vascular wall or in areas with typical diffuse Aβ deposition, with the labeling not enhanced by section pretreatment with heating or formic acid. Levels of a major sortilin fragment ~15 kDa, predicted to derive from the C-terminal region, were dramatically elevated in AD relative to control cortical lysates. Thus, sortilin fragments are a prominent constituent of the extracellularly deposited protein products at SPs in human cerebrum.

  20. Highlighting Interleukin-36 Signalling in Plaque Psoriasis and Pustular Psoriasis.

    Science.gov (United States)

    Furue, Kazuhisa; Yamamura, Kazuhiko; Tsuji, Gaku; Mitoma, Chikage; Uchi, Hiroshi; Nakahara, Takeshi; Kido-Nakahara, Makiko; Kadono, Takafumi; Furue, Masutaka

    2018-01-12

    Plaque psoriasis and pustular psoriasis are overlapping, but distinct, disorders. The therapeutic response to biologics supports the pivotal role of the tumour necrosis alpha (TNF-?)/ interleukin (IL)-23/IL-17/IL-22 axis in the pathogenesis of these disorders. Recently, functional activation of the IL-36 receptor (IL-36R) was discovered to be another driving force in the pathogenesis of psoriasis. This was first highlighted by the discovery that a loss-of-function mutation of the IL-36R antagonist (IL-36Ra) causes pustular psoriasis. Although the TNF-?/IL-23/IL-17/IL-22 axis and the functional activation of IL-36R are fundamentally involved in plaque psoriasis and pustular psoriasis, respectively, the 2 pathways are closely related and mutually reinforced, resulting in full-blown clinical manifestations. This review summarizes current topics on how IL-36 agonists (IL-36?, IL-36?, IL-36?) signal IL-36R, the pathological expression of IL-36 agonists and IL-36Ra in plaque and pustular psoriatic lesions, and the cross-talk between the TNF-?/IL-23/IL-17/IL-22 axis and the functional activation of IL-36R in the epidermal milieu.

  1. Identification and analysis of senile plaques using nuclear microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Landsberg, J P; Roberts, J M; Grime, G W; Watt, F [Nuclear Physics Lab., Oxford (UK); McDonald, B [Dept. of Neuropathology, Radcliffe Infirmary, Oxford (UK) Nuffield Dept. of Pathology, John Radcliffe Hospital, Oxford (UK) MRC Neuroanatomical Unit, Dept. of Pharmacology, Oxford (UK)

    1991-03-01

    The senile plaques and neuro-fibrillary tangles which form part of the pathology of Alzheimer's disease have come under increasing scrutiny over the last decade. In particular, much work has been done investigating their elemental composition. The suggestion that 75-100% of tensile plaques with mature cores contain aluminium and silicon, probably in the form of alumino-silicates, has led to increasing speculation about the role of these elements in the disease. SPM preliminary studies suggest that aluminium and silicon are not present in as great a proportion of senile plaques as presented in the literature. The situation is complicated by the fact that airborn and solubilised salts of aluminium and silicon may be encountered as contamination. They have been found, for example, in granular or crystalline form in the Aristar grade organic laboratory reagents used for staining the tissue, and in the pure pioloform used to back the samples. The latest results from scans of stained and unstained Alzheimer tissue are presented. (orig.).

  2. Identification and analysis of senile plaques using nuclear microscopy

    International Nuclear Information System (INIS)

    Landsberg, J.P.; Roberts, J.M.; Grime, G.W.; Watt, F.; McDonald, B.

    1991-01-01

    The senile plaques and neuro-fibrillary tangles which form part of the pathology of Alzheimer's disease have come under increasing scrutiny over the last decade. In particular, much work has been done investigating their elemental composition. The suggestion that 75-100% of tensile plaques with mature cores contain aluminium and silicon, probably in the form of alumino-silicates, has led to increasing speculation about the role of these elements in the disease. SPM preliminary studies suggest that aluminium and silicon are not present in as great a proportion of senile plaques as presented in the literature. The situation is complicated by the fact that airborn and solubilised salts of aluminium and silicon may be encountered as contamination. They have been found, for example, in granular or crystalline form in the Aristar grade organic laboratory reagents used for staining the tissue, and in the pure pioloform used to back the samples. The latest results from scans of stained and unstained Alzheimer tissue are presented. (orig.)

  3. HDL-mimetic PLGA nanoparticle to target atherosclerosis plaque macrophages.

    Science.gov (United States)

    Sanchez-Gaytan, Brenda L; Fay, Francois; Lobatto, Mark E; Tang, Jun; Ouimet, Mireille; Kim, YongTae; van der Staay, Susanne E M; van Rijs, Sarian M; Priem, Bram; Zhang, Liangfang; Fisher, Edward A; Moore, Kathryn J; Langer, Robert; Fayad, Zahi A; Mulder, Willem J M

    2015-03-18

    High-density lipoprotein (HDL) is a natural nanoparticle that exhibits an intrinsic affinity for atherosclerotic plaque macrophages. Its natural targeting capability as well as the option to incorporate lipophilic payloads, e.g., imaging or therapeutic components, in both the hydrophobic core and the phospholipid corona make the HDL platform an attractive nanocarrier. To realize controlled release properties, we developed a hybrid polymer/HDL nanoparticle composed of a lipid/apolipoprotein coating that encapsulates a poly(lactic-co-glycolic acid) (PLGA) core. This novel HDL-like nanoparticle (PLGA-HDL) displayed natural HDL characteristics, including preferential uptake by macrophages and a good cholesterol efflux capacity, combined with a typical PLGA nanoparticle slow release profile. In vivo studies carried out with an ApoE knockout mouse model of atherosclerosis showed clear accumulation of PLGA-HDL nanoparticles in atherosclerotic plaques, which colocalized with plaque macrophages. This biomimetic platform integrates the targeting capacity of HDL biomimetic nanoparticles with the characteristic versatility of PLGA-based nanocarriers.

  4. Visual cortical somatosensory and brainstem auditory evoked potentials following incidental irradiation of the rhombencephalon

    International Nuclear Information System (INIS)

    Nightingale, S.; Schofield, I.S.; Dawes, P.J.D.K.

    1984-01-01

    Visual, cortical somatosensory and brainstem auditory evoked potentials were recorded before incidental irradiation of the rhombencephalon during radiotherapy in and around the middle ear, and at 11 weeks and eight months after completion of treatment. No patient experienced neurological symptoms during this period. No consistent changes in evoked potentials were found. The failure to demonstrate subclinical radiation-induced demyelination suggests either that the syndrome of early-delayed radiation rhombencephalopathy occurs in an idiosyncratic manner, or that any subclinical lesions are not detectable by serial evoked potential recordings. (author)

  5. Exploding Head Syndrome as Aura of Migraine with Brainstem Aura: A Case Report.

    Science.gov (United States)

    Rossi, Fabian H; Gonzalez, Elizabeth; Rossi, Elisa Marie; Tsakadze, Nina

    2018-01-01

    This article reports a case of exploding head syndrome (EHS) as an aura of migraine with brainstem aura (MBA). A middle-aged man presented with intermittent episodes of a brief sensation of explosion in the head, visual flashing, vertigo, hearing loss, tinnitus, confusion, ataxia, dysarthria, and bilateral visual impairment followed by migraine headache. The condition was diagnosed as MBA. Explosive head sensation, sensory phenomena, and headaches improved over time with nortriptyline. This case shows that EHS can present as a primary aura symptom in patients with MBA.

  6. Increased brainstem perfusion, but no blood-brain barrier disruption, during attacks of migraine with aura.

    Science.gov (United States)

    Hougaard, Anders; Amin, Faisal M; Christensen, Casper E; Younis, Samaira; Wolfram, Frauke; Cramer, Stig P; Larsson, Henrik B W; Ashina, Messoud

    2017-06-01

    See Moskowitz (doi:10.1093/brain/awx099) for a scientific commentary on this article.The migraine aura is characterized by transient focal cortical disturbances causing dramatic neurological symptoms that are usually followed by migraine headache. It is currently not understood how the aura symptoms are related to the headache phase of migraine. Animal studies suggest that cortical spreading depression, the likely mechanism of migraine aura, causes disruption of the blood-brain barrier and noxious stimulation of trigeminal afferents leading to activation of brainstem nuclei and triggering of migraine headache. We used the sensitive and validated technique of dynamic contrast-enhanced high-field magnetic resonance imaging to simultaneously investigate blood-brain barrier permeability and tissue perfusion in the brainstem (at the level of the lower pons), visual cortex, and brain areas of the anterior, middle and posterior circulation during spontaneous attacks of migraine with aura. Patients reported to our institution to undergo magnetic resonance imaging during the headache phase after presenting with typical visual aura. Nineteen patients were scanned during attacks and on an attack-free day. The mean time from attack onset to scanning was 7.6 h. We found increased brainstem perfusion bilaterally during migraine with aura attacks. Perfusion also increased in the visual cortex and posterior white matter following migraine aura. We found no increase in blood-brain barrier permeability in any of the investigated regions. There was no correlation between blood-brain barrier permeability, brain perfusion, and time from symptom onset to examination or pain intensity. Our findings demonstrate hyperperfusion in brainstem during the headache phase of migraine with aura, while the blood-brain barrier remains intact during attacks of migraine with aura. These data thus contradict the preclinical hypothesis of cortical spreading depression-induced blood-brain barrier

  7. A rare case of acute poster ior reversible encephalopathy syndrome involving brainstem in a child

    Directory of Open Access Journals (Sweden)

    Olfa Chakroun-Walha

    2016-11-01

    Full Text Available Posterior reversible encephalopathy syndrome (PRES is a rare entity involving brainstem in very rare reported cases. We describe here the case of a boy who presented to the emergency department for headaches and strabismus. Diagnosis of PRES was retained by magnetic resonance imaging. The causes were blood pressure urgency and renal failure. Location of lesions was very rarely reported in literature and neurological troubles were persistent. Emergency physicians should evocate PRES each time there is a clinical context associated with neurological troubles by a normal brain CT scan. Early diagnosis is very important to treat its causes and improve prognosis.

  8. Visual cortical somatosensory and brainstem auditory evoked potentials following incidental irradiation of the rhombencephalon

    Energy Technology Data Exchange (ETDEWEB)

    Nightingale, S. (Royal Victoria Infirmary, Newcastle upon Tyne (UK)); Schofield, I.S.; Dawes, P.J.D.K. (Newcastle upon Tyne Univ. (UK). Newcastle General Hospital)

    1984-01-01

    Visual, cortical somatosensory and brainstem auditory evoked potentials were recorded before incidental irradiation of the rhombencephalon during radiotherapy in and around the middle ear, and at 11 weeks and eight months after completion of treatment. No patient experienced neurological symptoms during this period. No consistent changes in evoked potentials were found. The failure to demonstrate subclinical radiation-induced demyelination suggests either that the syndrome of early-delayed radiation rhombencephalopathy occurs in an idiosyncratic manner, or that any subclinical lesions are not detectable by serial evoked potential recordings.

  9. Enhanced Excitatory Connectivity and Disturbed Sound Processing in the Auditory Brainstem of Fragile X Mice.

    Science.gov (United States)

    Garcia-Pino, Elisabet; Gessele, Nikodemus; Koch, Ursula

    2017-08-02

    Hypersensitivity to sounds is one of the prevalent symptoms in individuals with Fragile X syndrome (FXS). It manifests behaviorally early during development and is often used as a landmark for treatment efficacy. However, the physiological mechanisms and circuit-level alterations underlying this aberrant behavior remain poorly understood. Using the mouse model of FXS ( Fmr1 KO ), we demonstrate that functional maturation of auditory brainstem synapses is impaired in FXS. Fmr1 KO mice showed a greatly enhanced excitatory synaptic input strength in neurons of the lateral superior olive (LSO), a prominent auditory brainstem nucleus, which integrates ipsilateral excitation and contralateral inhibition to compute interaural level differences. Conversely, the glycinergic, inhibitory input properties remained unaffected. The enhanced excitation was the result of an increased number of cochlear nucleus fibers converging onto one LSO neuron, without changing individual synapse properties. Concomitantly, immunolabeling of excitatory ending markers revealed an increase in the immunolabeled area, supporting abnormally elevated excitatory input numbers. Intrinsic firing properties were only slightly enhanced. In line with the disturbed development of LSO circuitry, auditory processing was also affected in adult Fmr1 KO mice as shown with single-unit recordings of LSO neurons. These processing deficits manifested as an increase in firing rate, a broadening of the frequency response area, and a shift in the interaural level difference function of LSO neurons. Our results suggest that this aberrant synaptic development of auditory brainstem circuits might be a major underlying cause of the auditory processing deficits in FXS. SIGNIFICANCE STATEMENT Fragile X Syndrome (FXS) is the most common inheritable form of intellectual impairment, including autism. A core symptom of FXS is extreme sensitivity to loud sounds. This is one reason why individuals with FXS tend to avoid social

  10. Association between diabetes and different components of coronary atherosclerotic plaque burden as measured by coronary multidetector computed tomography.

    Science.gov (United States)

    Yun, Chun-Ho; Schlett, Christopher L; Rogers, Ian S; Truong, Quynh A; Toepker, Michael; Donnelly, Patrick; Brady, Thomas J; Hoffmann, Udo; Bamberg, Fabian

    2009-08-01

    The aim of the study was to assess differences in the presence, extent, and composition of coronary atherosclerotic plaque burden as detected by coronary multidetector computed tomography (MDCT) between patients with and without diabetes mellitus. We compared coronary atherosclerotic plaques (any plaque, calcified [CAP], non-calcified [NCAP, and mixed plaque [MCAP

  11. HDL mimetic CER-001 targets atherosclerotic plaques in patients.

    Science.gov (United States)

    Zheng, Kang He; van der Valk, Fleur M; Smits, Loek P; Sandberg, Mara; Dasseux, Jean-Louis; Baron, Rudi; Barbaras, Ronald; Keyserling, Constance; Coolen, Bram F; Nederveen, Aart J; Verberne, Hein J; Nell, Thijs E; Vugts, Danielle J; Duivenvoorden, Raphaël; Fayad, Zahi A; Mulder, Willem J M; van Dongen, Guus A M S; Stroes, Erik S G

    2016-08-01

    Infusion of high-density lipoprotein (HDL) mimetics aimed at reducing atherosclerotic burden has led to equivocal results, which may relate in part to the inability of HDL mimetics to adequately reach atherosclerotic lesions in humans. This study evaluated delivery of recombinant human apolipoprotein A-I (apoA-I) containing HDL mimetic CER-001 in carotid plaques in patients. CER-001 was radiolabeled with the long-lived positron emitter zirconium-89 ((89)Zr) to enable positron emission tomography with computed tomography (PET/CT) imaging. Eight patients with atherosclerotic carotid artery disease (>50% stenosis) received a single infusion of unlabeled CER-001 (3 mg/kg), co-administered with 10 mg of (89)Zr-labeled CER-001 (18 MBq). Serial PET/CT imaging and contrast enhanced-magnetic resonance imaging (CE-MRI) were performed to evaluate targeted delivery of CER-001. One hour after infusion, mean plasma apoA-I levels increased by 9.9 mg/dL (p = 0.026), with a concomitant relative increase in the plasma cholesterol efflux capacity of 13.8% (p CER-001 expressed as target-to-background ratio (TBRmax) increased significantly 24 h after infusion, and remained increased up to 48 h (TBRmax t = 10 min: 0.98; t = 24 h: 1.14 (p = 0.001); t = 48 h: 1.12 (p = 0.007)). TBRmax was higher in plaque compared with non-plaque segments (1.18 vs. 1.05; p CER-001 increases plasma apoA-I concentration and plasma cholesterol efflux capacity. Our data support the concept that CER-001 targets plaque regions in patients, which correlates with plaque contrast enhancement. These clinical findings may also guide future nanomedicine development using HDL particles for drug delivery in atherosclerosis. Netherlands Trial Registry - NTR5178. http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=5178. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  12. Spectral CT imaging of vulnerable plaque with two independent biomarkers

    International Nuclear Information System (INIS)

    Baturin, Pavlo; Alivov, Yahya; Molloi, Sabee

    2012-01-01

    The purpose of this paper is to investigate the feasibility of a novel four-material decomposition technique for assessing the vulnerability of plaque with two contrast materials spectral computer tomography (CT) using two independent markers: plaque's inflammation and spotty calcification. A simulation study was conducted using an energy-sensitive photon-counting detector for k-edge imaging of the coronary arteries. In addition to detecting the inflammation status, which is known as a biological marker of a plaque's vulnerability, we use spotty calcium concentration as an independent marker to test a plaque's vulnerability. We have introduced a new method for detecting and quantifying calcium concentrations in the presence of two contrast materials (iodine and gold), calcium and soft tissue background. In this method, four-material decomposition was performed on a pixel-by-pixel basis, assuming there was an arbitrary mixture of materials in the voxel. The concentrations of iodine and gold were determined by the k-edge material decomposition based on the maximum likelihood method. The calibration curves of the attenuation coefficients, with respect to the concentrations of different materials, were used to separate the calcium signal from both contrast materials and different soft tissues in the mixtures. Three different materials (muscle, blood and lipid) were independently used as soft tissue. The simulations included both ideal and more realistic energy resolving detectors to measure the polychromatic photon spectrum in single slice parallel beam geometry. The ideal detector was used together with a 3 cm diameter digital phantom to demonstrate the decomposition method while a more realistic detector and a 33 × 24 cm 2 digital chest phantom were simulated to validate the vulnerability assessment technique. A 120 kVp spectrum was generated to produce photon flux sufficient for detecting contrast materials above the k-edges of iodine (33.2 keV) and gold (80.7 ke

  13. Atherosclerosis and the vulnerable plaque - imaging. Part II

    International Nuclear Information System (INIS)

    Worthley, S.G.; Helft, G.; Zaman, A.G.; Fuster, V.; Badimon, J.J.

    2000-01-01

    Atherosclerotic disease and its thrombotic complications remain the leading causes of mortality and morbidity in Western society. In Australia, cardiovascular disease (CVD) is responsible for one in every 2.4 (41%) deaths and is the leading single cause of mortality. The crucial final common process for the conversion of a non-occlusive, often clinically silent, atherosclerotic lesion to a potentially fatal condition is plaque disruption. The mortality associated with atherosclerotic disease relates to the acute coronary syndromes, including acute myocardial infarction (MI), unstable angina pectoris and sudden cardiac death. There is substantial clinical, experimental and post-mortem evidence demonstrating the role played by acute thrombosis upon a disrupted atherosclerotic plaque in the onset of acute coronary syndromes. Atherosclerotic plaque composition, rather than the stenotic severity, appears to be central in determining risk of both plaque rupture and subsequent thrombogenicity. In particular, a large lipid core and a thin fibrous cap render an atherosclerotic lesion susceptible or vulnerable to these complications. We are currently limited in our ability to identify accurately patients at risk for an acute coronary event. The armamentarium of diagnostic investigations, both non-invasive and invasive, currently clinically available is only able to provide us with data related to the stenotic severity of a coronary artery. The non-invasive testing includes stress-induced (exercise or pharmacologic) ischaemic changes in electrical repolarisation, wall motion or myocardial radioactive-tracer uptake. The invasive test of coronary angiography, although the current gold standard for the detection of coronary atherosclerotic disease, provides us with no data about the composition of the atherosclerotic lesion. However, the vast majority of acute coronary events involve a non-critically stenosed atherosclerotic lesion, and thus with currently available means of

  14. Optical Coherence Tomography Analysis of Attenuated Plaques Detected by Intravascular Ultrasound in Patients with Acute Coronary Syndromes

    Directory of Open Access Journals (Sweden)

    Takashi Kubo

    2011-01-01

    Full Text Available Background. Recent intravascular ultrasound (IVUS studies have demonstrated that hypoechoic plaque with deep ultrasound attenuation despite absence of bright calcium is common in acute coronary syndrome. Such “attenuated plaque” may be an IVUS characteristic of unstable lesion. Methods. We used optical coherence tomography (OCT in 104 patients with unstable angina to compare lesion characteristics between IVUS-detected attenuated plaque and nonattenuated plaque. Results. IVUS-detected attenuated plaque was observed in 41 (39% patients. OCT-detected lipidic plaque (88% versus 49%, <0.001, thin-cap fibroatheroma (48% versus 16%, <0.001, plaque rupture (44% versus 11%, <0.001, and intracoronary thrombus (54% versus 17%, <0.001 were more often seen in IVUS-detected attenuated plaques compared with nonattenuated plaques. Conclusions. IVUS-detected attenuated plaque has many characteristics of unstable coronary lesion. The presence of attended plaque might be an important marker of lesion instability.

  15. Novel Anterior Brainstem Magnetic Resonance Imaging Findings in Non-Small Cell Lung Cancer with Leptomeningeal Carcinomatosis

    Directory of Open Access Journals (Sweden)

    Chun-Yu Cheng

    2017-10-01

    Full Text Available Leptomeningeal carcinomatosis (LC is found in around 4% of patients with non-small cell lung cancer (NSCLC. The most common radiological finding of LC is diffuse leptomeningeal enhancement on contrast-enhanced brain magnetic resonance imaging (MRI. Herein, we report a novel brain MRI finding—non-enhanced, band-like, symmetric restricted diffusion along the anterior surface of the brainstem—of LC in four patients with NSCLC. We also identified three additional cases with similar MRI findings in a literature review. We hypothesized that the restricted diffusion along the anterior brainstem was caused by malignant cells concentrating in the cistern around the brainstem and infiltrating into the circumferential perforating arteries along the anterior brainstem surface, which then resulted in microinfarctions.

  16. Natural history of dental plaque accumulation in mechanically ventilated adults: a descriptive correlational study.

    Science.gov (United States)

    Jones, Deborah J; Munro, Cindy L; Grap, Mary Jo

    2011-12-01

    The purpose of this study was to describe the pattern of dental plaque accumulation in mechanically ventilated adults. Accumulation of dental plaque and bacterial colonisation of the oropharynx is associated with a number of systemic diseases including ventilator associated pneumonia. Data were collected from mechanically ventilated critically ill adults (n=137), enrolled within 24 hours of intubation. Dental plaque, counts of decayed, missing and filled teeth and systemic antibiotic use was assessed on study days 1, 3, 5 and 7. Dental plaque averages per study day, tooth type and tooth location were analysed. Medical respiratory, surgical trauma and neuroscience ICU's of a large tertiary care centre in the southeast United States. Plaque: all surfaces >60% plaque coverage from day 1 to day 7; molars and premolars contained greatest plaque average >70%. Systemic antibiotic use on day 1 had no significant effect on plaque accumulation on day 3 (p=0.73). Patients arrive in critical care units with preexisting oral hygiene issues. Dental plaque tends to accumulate in the posterior teeth (molars and premolars) that may be hard for nurses to visualise and reach; this problem may be exacerbated by endotracheal tubes and other equipment. Knowing accumulation trends of plaque will guide the development of effective oral care protocols. Published by Elsevier Ltd.

  17. Multiple yellow plaques assessed by angioscopy with quantitative colorimetry in patients with myocardial infarction.

    Science.gov (United States)

    Inami, Shigenobu; Ishibashi, Fumiyuki; Waxman, Sergio; Okamatsu, Kentaro; Seimiya, Koji; Takano, Masamichi; Uemura, Ryota; Sano, Junko; Mizuno, Kyoichi

    2008-03-01

    Multiple angioscopic yellow plaques are associated with diffuse atherosclerotic plaque, and may be prevalent in patients with myocardial infarction (MI), so in the present study the yellow plaques in the coronary arteries of patients with MI was evaluated using quantitative colorimetry, and compared with those of patients with stable angina (SA). In the recorded angioscopic images of 3 coronary vessels in 29 patients (15 patients with MI, 14 with SA), yellow plaques were determined as visually yellow regions with b* value >0 (yellow color intensity) measured by the quantitative colorimetric method. A total of 90 yellow plaques were identified (b* =19.35+/-8.3, 3.05-45.35). Yellow plaques were significantly more prevalent in 14 (93%) of 15 culprit lesions of MI as compared with 8 (57%) of 14 of SA (p=0.03). In non-culprit segments, yellow plaques were similarly prevalent in 13 (87%) patients with MI and 11 (79%) with SA (p=0.65). Overall, multiple (> or =2) yellow plaques were prevalent in 13 (87%) patients with MI, similar to the 10 (71%) with SA (p=0.38). The number of yellow plaques was significantly higher in patients with MI (3.8+/-1.9) than in those with SA (2.4+/-1.6, p=0.03). The present study suggests that patients with MI tend to have diffuse atherosclerotic plaque in their coronary arteries.

  18. Photoabalation in dental hard substances and atheromatous plaques - The efficiency and selectivity criteria for surgery

    International Nuclear Information System (INIS)

    Jean, B.

    1995-01-01

    The basic principals of IR photoabalation are relatively easy to understand as long as water is the predominant absorber in the target tissue (e.g. brain tissue, cornea). Dental hard substances are typical target materials for the study of biological materials with low water content (30%) Its main constituent is hydroxyapatit (50%) with maximal absorption at 9.5 μm wavelength. The photoablation efficiency, the collateral thermal damage and the resultant formation of thermally induced surface cracks were investigated. Unlike the 2.95 μm of the Er:YAG, already in use, the 9.5 μm radiation minimizes the penetration depth; as a consequence, the volume of heated material per pulse is minimal too and thus thermal cracks - a potential source of caries are avoided. Furthermore at 9.5 μm, the ablation threshold requires a minimal fluence; this is an element of selectivity, limiting photoablation to dentin and enamel, while neighboring gingiva cannot be ablated accidentally. Removal of atherosclerotic plaques for recanalization of obliterated cardiac vessels (laser angioplasty) is a minimally invasive surgical procedure of highest socioeconomic relevance. The rather inhomogeneous composition of apatit and colesterol (both absorbing at 9.5 μm) make plaques a particularly complex target material; while the ablation efficiency has to be high, the related shock wave should be minimal. The open-quote selectivity close-quote criterion of the ablation process must avoid accidental perforation of the underlying vessel walls (composed of connective tissue with high water content), a deadly complication exclamation point Experimental results with FELIX will be demonstrated. Photoacoustic spectroscopy in a recently developed non contact mode has been proved to provide various informations (on line) about the IR-photoablation process

  19. No calcium-fluoride-like deposits detected in plaque shortly after a sodium fluoride mouthrinse.

    Science.gov (United States)

    Vogel, G L; Tenuta, L M A; Schumacher, G E; Chow, L C

    2010-01-01

    Plaque 'calcium-fluoride-like' (CaF(2)-like) and fluoride deposits held by biological/bacterial calcium fluoride (Ca-F) bonds appear to be the source of cariostatic concentrations of fluoride in plaque fluid. The aim of this study was to quantify the amounts of plaque fluoride held in these reservoirs after a sodium fluoride rinse. 30 and 60 min after a 228 microg/g fluoride rinse, plaque samples were collected from 11 volunteers. Each sample was homogenized, split into 2 aliquots (aliquots 1 and 2), centrifuged, and the recovered plaque fluid combined and analyzed using microelectrodes. The plaque mass from aliquot 1 was retained. The plaque mass from aliquot 2 was extracted several times with a solution having the same fluoride, calcium and pH as the plaque fluid in order to extract the plaque CaF(2)-like deposits. The total fluoride in both aliquots was then determined. In a second experiment, the extraction completeness was examined by applying the above procedure to in vitro precipitates containing known amounts of CaF(2)-like deposits. Nearly identical fluoride concentrations were found in both plaque aliquots. The extraction of the CaF(2)-like precipitates formed in vitro removed more than 80% of these deposits. The results suggest that either CaF(2)-like deposits were not formed in plaque or, if these deposits had been formed, they were rapidly lost. The inability to form persistent amounts of CaF(2)-like deposits in plaque may account for the relatively rapid loss of plaque fluid fluoride after the use of conventional fluoride dentifrices or rinses. (c) 2010 S. Karger AG, Basel.

  20. Can high frequency ultrasound and MRI diagnose malignant atheromatous plaque in vitro?

    International Nuclear Information System (INIS)

    Yoshida, Shigeo; Nieminen, M.S.; Paananen, T.; Kahri, A.

    1995-01-01

    It remains a vital clinical issue how to diagnose malignant atheromatous plaques consisting of ulcerative plaque and hemorrhagic plaque, which are potential risks for thrombosis and the arterial spasm. This study proposes further investigations to develop methods in order to detect this type of lesions by echocardiography. In this study, we tested high frequency (7.5 MHz) US and 1.0 T MRI (Tl weighted SE, STIR; short time inversion recovery sequence, and Tl weighted fat suppression technique) for their precision in the diagnosis of atheromatous plaque as malignant or benign in postmortem human aorta. Ten hemorrhagic plaques were imaged as heterogeneous echo-pattern in the shoulder of plaques covered with high-echo capsule with US; however, these findings were also obtained from 2 of 16 non-hemorrhagic plaques. With TlSE, hemorrhagic plaques were revealed as mixed areas of reduced intensity and high intensity which were differentiated from fatty deposition with Tl weighted fat suppression technique. Ulcerative plaques were revealed as concave shaped plaques and diagnosed correctly with both methods. US was superior to MRI from the viewpoints of examination time and measuring wall thickness. US indicated intimal plus medial thickness of hemorrhagic plaque and non-hemorrhagic plaque at 4.3+1.1 mm and 3.0+1.0 mm (p<0.05) respectively. MRI was vulnerable to artifacts and its image was poorer in quality due to its lower resolution: however, probably because of its superior ability to distinguish fatty deposition from hemorrhage, MRI ultimately enabled more accurate diagnosis than US, as long as its image was fairly clear. The overall accuracies were 80% with US and 85.7% with MRI as confirmed by histological tests. From these results, the careful analysis of the two images obtained from US and MRI enables clinical diagnosis of malignant atheromatous plaques. (author)

  1. Activation of Brainstem Pro-opiomelanocortin Neurons Produces Opioidergic Analgesia, Bradycardia and Bradypnoea.

    Science.gov (United States)

    Cerritelli, Serena; Hirschberg, Stefan; Hill, Rob; Balthasar, Nina; Pickering, Anthony E

    2016-01-01

    Opioids are widely used medicinally as analgesics and abused for hedonic effects, actions that are each complicated by substantial risks such as cardiorespiratory depression. These drugs mimic peptides such as β-endorphin, which has a key role in endogenous analgesia. The β-endorphin in the central nervous system originates from pro-opiomelanocortin (POMC) neurons in the arcuate nucleus and nucleus of the solitary tract (NTS). Relatively little is known about the NTSPOMC neurons but their position within the sensory nucleus of the vagus led us to test the hypothesis that they play a role in modulation of cardiorespiratory and nociceptive control. The NTSPOMC neurons were targeted using viral vectors in a POMC-Cre mouse line to express either opto-genetic (channelrhodopsin-2) or chemo-genetic (Pharmacologically Selective Actuator Modules). Opto-genetic activation of the NTSPOMC neurons in the working heart brainstem preparation (n = 21) evoked a reliable, titratable and time-locked respiratory inhibition (120% increase in inter-breath interval) with a bradycardia (125±26 beats per minute) and augmented respiratory sinus arrhythmia (58% increase). Chemo-genetic activation of NTSPOMC neurons in vivo was anti-nociceptive in the tail flick assay (latency increased by 126±65%, pneurons were found to project to key brainstem structures involved in cardiorespiratory control (nucleus ambiguus and ventral respiratory group) and endogenous analgesia (periaqueductal gray and midline raphe). Thus the NTSPOMC neurons may be capable of tuning behaviour by an opioidergic modulation of nociceptive, respiratory and cardiac control.

  2. Large central lesions compressing the hypothalamus and brainstem. Operative approaches and combination treatment with radiosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Hiroshi K.; Negishi, Masatoshi; Kohga, Hideaki; Hirato, Masafumi; Ohye, Chihiro [Gunma Univ., Maebashi (Japan). School of Medicine; Shibazaki, Tohru

    1998-09-01

    A major aim of minimally invasive neurosurgery is to preserve function in the brain and cranial nerves. Based on previous results of radiosurgery for central lesions (19 craniopharyngiomas, 46 pituitary adenomas, 9 meningeal tumors), combined micro- and/or radiosurgery was applied for large lesions compressing the hypothalamus and/or brainstem. A basal interhemispheric approach via superomedial orbitotomy or a transcallosal-transforaminal approach was used for these large tumors. Tumors left behind in the hypothalamus or cavernous sinus were treated with radiosurgery using a gamma unit. Preoperative hypothalamo-pituitary functions were preserved in most of these patients. Radiosurgical results were evaluated in patients followed for more than 2 years after treatment. All 9 craniopharyngiomas decreased in size after radiosurgery, although a second treatment was required in 4 patients. All 20 pituitary adenomas were stable or decreased in size and 5 of 7 functioning adenomas showed normalized values of hormones in the serum. All 3 meningeal tumors were stable or decreased in size after treatment. No cavernous sinus symptoms developed after radiosurgery. We conclude that combined micro- and radio-neurosurgery is an effective and less invasive treatment for large central lesions compressing the hypothalamus and brainstem. (author)

  3. Inflammatory lesions of the brainstem and the cerebellopontine angle; Entzuendungen des Hirnstamms und des Kleinhirnbrueckenwinkels

    Energy Technology Data Exchange (ETDEWEB)

    Lutz, J.; Jaeger, L. [Klinikum Grosshadern der Ludwig-Maximilians-Universitaet Muenchen (Germany). Institut fuer Klinische Radiologie

    2006-03-15

    Inflammatory lesions of the brainstem and the cerebellopontine angle are often critical for the patient, because crucial neuronal and vascular structures are found in this region. The patient's prognosis mainly depends on rapid identification of the inflammation site and the radiological evaluation of the inflammation pathogenesis to develop therapeutic strategies. Therefore, cross-sectional imaging is complementary to laboratory and CSF analysis as well as biopsies. This article gives a survey of inflammatory lesions of the brainstem and the cerebellopontine angle. (orig.) [German] Entzuendliche Erkrankungen des Hirnstamms und Kleinhirnbrueckenwinkels stellen nicht selten eine kritische Situation fuer den Patienten dar, da in diesen Regionen wichtige neuronale Strukturen und Gefaesse verlaufen. Die Prognose und das weitere therapeutische Vorgehen haengen entscheidend von einer schnellen Diagnose der Entzuendungslokalisation sowie einer bildmorphologischen Einordnung der Entzuendungspathogenese ab. Folglich ergaenzt die Schnittbildgebung entscheidend die Liquoranalyse, die Biopsie und die Laboruntersuchungen. In diesem Artikel soll eine Uebersicht ueber die verschiedenen entzuendlichen Veraenderungen des Hirnstamms und Kleinhirnbrueckenwinkels gegeben werden. (orig.)

  4. Proton spectroscopy in the narcoleptic syndrome. Is there evidence of a brainstem lesion?

    Science.gov (United States)

    Ellis, C M; Simmons, A; Lemmens, G; Williams, S C; Parkes, J D

    1998-02-01

    There is controversy regarding the relationship of structural or biochemical brainstem lesions to "idiopathic" narcolepsy. Most cases of the narcoleptic syndrome are considered to be idiopathic because no structural lesion is detectable, although some cases of secondary narcolepsy are known to be associated with no structural brainstem lesions. Using proton spectroscopy, we determined levels of ventral pontine metabolite pools in 12 normal subjects and 12 subjects with idiopathic narcolepsy. REM sleep is generated in ventral pontine areas. Proton spectroscopy was used to study levels of N-acetyl aspartate (NAA) as a marker of cell mass, creatine and phosphocreatine (Cr + PCr), and choline (Cho). The intensity of the peaks, as determined by the area under the peak (AUP), was measured. The AUP correlates with the quantity of chemical present. In this study, the ratios of NAA to Cr + PCr were similar in normal subjects and in narcoleptic subjects with idiopathic narcolepsy. No differences in measured metabolic ratio were observed in subjects who slept during the scan procedure compared with those who remained awake. Subjects with "symptomatic" narcolepsy accompanied by an obvious structural brain lesion were not studied. Proton spectroscopy of the brain initiates a new kind of neurochemistry, allowing the noninvasive study of metabolic pools in the living human brain without the use of any kind of tracer or radioactive molecule. In this study, there was no evidence of cell loss in the ventral pontine areas of subjects with the narcoleptic syndrome.

  5. Speech-evoked auditory brainstem responses in children with hearing loss.

    Science.gov (United States)

    Koravand, Amineh; Al Osman, Rida; Rivest, Véronique; Poulin, Catherine

    2017-08-01

    The main objective of the present study was to investigate subcortical auditory processing in children with sensorineural hearing loss. Auditory Brainstem Responses (ABRs) were recorded using click and speech/da/stimuli. Twenty-five children, aged 6-14 years old, participated in the study: 13 with normal hearing acuity and 12 with sensorineural hearing loss. No significant differences were observed for the click-evoked ABRs between normal hearing and hearing-impaired groups. For the speech-evoked ABRs, no significant differences were found for the latencies of the following responses between the two groups: onset (V and A), transition (C), one of the steady-state wave (F), and offset (O). However, the latency of the steady-state waves (D and E) was significantly longer for the hearing-impaired compared to the normal hearing group. Furthermore, the amplitude of the offset wave O and of the envelope frequency response (EFR) of the speech-evoked ABRs was significantly larger for the hearing-impaired compared to the normal hearing group. Results obtained from the speech-evoked ABRs suggest that children with a mild to moderately-severe sensorineural hearing loss have a specific pattern of subcortical auditory processing. Our results show differences for the speech-evoked ABRs in normal hearing children compared to hearing-impaired children. These results add to the body of the literature on how children with hearing loss process speech at the brainstem level. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Effect of edaravone on acute brainstem-cerebellar infarction with vertigo and sudden hearing loss.

    Science.gov (United States)

    Inoue, Yuta; Yabe, Takao; Okada, Kazunari; Nakamura, Yuka

    2014-06-01

    We report 2 cases with acute brainstem and brainstem-cerebellar infarction showed improvement of their signs and symptoms after administration of edaravone. Case 1, a 74-year-old woman who experienced sudden vertigo, also had dysarthria and left hemiplegia. Magnetic resonance imaging (MRI) showed an abnormal region in the right ventrolateral medulla oblongata. The patient's vertigo and hemiplegia improved completely after treatment. Case 2, a 50-year-old man who experienced sudden vertigo and sensorineural hearing loss (SNHL), developed dysarthria after admission. MRI revealed acute infarction in the right cerebellar hemisphere. Magnetic resonance angiography revealed dissection of the basilar artery and occlusion of the right anterior inferior cerebellar artery. The patient's vertigo and hearing remarkably improved. We have described 2 patients whose early symptoms were vertigo and sudden SNHL, but who were later shown to have ischemic lesions of the central nervous system. Edaravone is neuroprotective drug with free radical-scavenging actions. Free radicals in the ear are responsible for ischemic damage. Edaravone, a free radical scavenger, may be useful in the treatment of vertigo and SNHL. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  7. Motor-circuit communication matrix from spinal cord to brainstem neurons revealed by developmental origin.

    Science.gov (United States)

    Pivetta, Chiara; Esposito, Maria Soledad; Sigrist, Markus; Arber, Silvia

    2014-01-30

    Accurate motor-task execution relies on continuous comparison of planned and performed actions. Motor-output pathways establish internal circuit collaterals for this purpose. Here we focus on motor collateral organization between spinal cord and upstream neurons in the brainstem. We used a newly developed mouse genetic tool intersectionally with viruses to uncover the connectivity rules of these ascending pathways by capturing the transient expression of neuronal subpopulation determinants. We reveal a widespread and diverse network of spinal dual-axon neurons, with coincident input to forelimb motor neurons and the lateral reticular nucleus (LRN) in the brainstem. Spinal information to the LRN is not segregated by motor pool or neurotransmitter identity. Instead, it is organized according to the developmental domain origin of the progenitor cells. Thus, excerpts of most spinal information destined for action are relayed to supraspinal centers through exquisitely organized ascending connectivity modules, enabling precise communication between command and execution centers of movement. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Brainstem GLP-1 signalling contributes to cancer anorexia-cachexia syndrome in the rat.

    Science.gov (United States)

    Borner, Tito; Liberini, Claudia G; Lutz, Thomas A; Riediger, Thomas

    2018-03-15

    The cancer anorexia-cachexia syndrome (CACS) is a frequent and severe condition in cancer patients. Currently, no pharmacological treatment is approved for the therapy of CACS. Centrally, glucagon-like peptide-1 (GLP-1) is expressed in the nucleus tractus solitarii (NTS) and is implicated in malaise, nausea and food aversion. The NTS is reciprocally connected to brain sites implicated in the control of energy balance including the area postrema (AP), which mediates CACS in certain tumour models. Given the role of GLP-1 as a mediator of anorexia under acute sickness conditions, we hypothesized that brainstem GLP-1 signalling might play a role in the mediation of CACS. Using hepatoma tumour-bearing (TB) rats, we first tested whether the chronic delivery of the GLP-1R antagonist exendin-9 (Ex-9) into the fourth ventricle attenuates CACS. Second, we investigated whether a genetic knockdown of GLP-1 expression in the NTS ameliorates CACS. Ex-9 attenuated anorexia, body weight loss, muscle and fat depletion compared to TB controls. Similarly, TB animals with a knockdown of GLP-1 expression in the NTS had higher food intake, reduced body weight loss, and higher lean and fat mass compared to TB controls. Our study identifies brainstem GLP-1 as crucial mediator of CACS in hepatoma TB rats. The GLP-1R represents a promising target against CACS and possibly other forms of disease-related anorexia/cachexia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Immunohistochemical Mapping of TRK-Fused Gene Products in the Rat Brainstem

    International Nuclear Information System (INIS)

    Takeuchi, Shigeko; Masuda, Chiaki; Maebayashi, Hisae; Tooyama, Ikuo

    2012-01-0