WorldWideScience

Sample records for brain ct scan

  1. Brain CT scanning of children with purulent meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Mishima, M.; Suzuki, M.; Nagata, M.; Kawamura, G.

    1986-12-01

    Nine of 21 children with purulent meningitis showed abnormal findings in brain CT when admitted. All of the abnormal group were less than 12 months of age, but 75 % of the normal group were more than 1 year old. The period of positive CRP was longer and the level of sugar in CSF was lower in abnormal group when compared with normal group. Because convulsion and EEG abnormalities were observed similarly in both groups, it may be difficult to determine the organic changes of the brain clinically. Brain CT scanning is recommended as soon as possible after the onset of purulent meningitis.

  2. Exploring miniature insect brains using micro-CT scanning techniques.

    Science.gov (United States)

    Smith, Dylan B; Bernhardt, Galina; Raine, Nigel E; Abel, Richard L; Sykes, Dan; Ahmed, Farah; Pedroso, Inti; Gill, Richard J

    2016-02-24

    The capacity to explore soft tissue structures in detail is important in understanding animal physiology and how this determines features such as movement, behaviour and the impact of trauma on regular function. Here we use advances in micro-computed tomography (micro-CT) technology to explore the brain of an important insect pollinator and model organism, the bumblebee (Bombus terrestris). Here we present a method for accurate imaging and exploration of insect brains that keeps brain tissue free from trauma and in its natural stereo-geometry, and showcase our 3D reconstructions and analyses of 19 individual brains at high resolution. Development of this protocol allows relatively rapid and cost effective brain reconstructions, making it an accessible methodology to the wider scientific community. The protocol describes the necessary steps for sample preparation, tissue staining, micro-CT scanning and 3D reconstruction, followed by a method for image analysis using the freeware SPIERS. These image analysis methods describe how to virtually extract key composite structures from the insect brain, and we demonstrate the application and precision of this method by calculating structural volumes and investigating the allometric relationships between bumblebee brain structures.

  3. Exploring miniature insect brains using micro-CT scanning techniques

    OpenAIRE

    Smith, Dylan B.; Galina Bernhardt; Nigel E. Raine; Abel, Richard L.; Dan Sykes; Farah Ahmed; Inti Pedroso; Gill, Richard J.

    2016-01-01

    The capacity to explore soft tissue structures in detail is important in understanding animal physiology and how this determines features such as movement, behaviour and the impact of trauma on regular function. Here we use advances in micro-computed tomography (micro-CT) technology to explore the brain of an important insect pollinator and model organism, the bumblebee (Bombus terrestris). Here we present a method for accurate imaging and exploration of insect brains that keeps brain tissue ...

  4. Brain PET scan

    Science.gov (United States)

    ... have false results on a PET scan. Blood sugar or insulin levels may affect the test results in people with diabetes . PET scans may be done along with a CT scan. This combination scan is called a PET/CT. Alternative Names Brain positron emission tomography; PET scan - brain References Chernecky ...

  5. A comparison of sequential and spiral scanning techniques in brain CT.

    Science.gov (United States)

    Pace, Ivana; Zarb, Francis

    2015-01-01

    To evaluate and compare image quality and radiation dose of sequential computed tomography (CT) examinations of the brain and spiral CT examinations of the brain imaged on a GE HiSpeed NX/I Dual Slice 2CT scanner. A random sample of 40 patients referred for CT examination of the brain was selected and divided into 2 groups. Half of the patients were scanned using the sequential technique; the other half were scanned using the spiral technique. Radiation dose data—both the computed tomography dose index (CTDI) and the dose length product (DLP)—were recorded on a checklist at the end of each examination. Using the European Guidelines on Quality Criteria for Computed Tomography, 4 radiologists conducted a visual grading analysis and rated the level of visibility of 6 anatomical structures considered necessary to produce images of high quality. The mean CTDI(vol) and DLP values were statistically significantly higher (P vol): 22.06 mGy; DLP: 304.60 mGy • cm) than with the spiral scans (CTDI(vol): 14.94 mGy; DLP: 229.10 mGy • cm). The mean image quality rating scores for all criteria of the sequential scanning technique were statistically significantly higher (P <.05) in the visual grading analysis than those of the spiral scanning technique. In this local study, the sequential technique was preferred over the spiral technique for both overall image quality and differentiation between gray and white matter in brain CT scans. Other similar studies counter this finding. The radiation dose seen with the sequential CT scanning technique was significantly higher than that seen with the spiral CT scanning technique. However, image quality with the sequential technique was statistically significantly superior (P <.05).

  6. Learning Based Segmentation of CT Brain Images: Application to Post-Operative Hydrocephalic Scans

    OpenAIRE

    Cherukuri, Venkateswararao; Ssenyonga, Peter; Warf, Benjamin C.; Kulkarni, Abhaya V.; Monga, Vishal; Schiff, Steven J.

    2017-01-01

    Objective: Hydrocephalus is a medical condition in which there is an abnormal accumulation of cerebrospinal fluid (CSF) in the brain. Segmentation of brain imagery into brain tissue and CSF (before and after surgery, i.e. pre-op vs. postop) plays a crucial role in evaluating surgical treatment. Segmentation of pre-op images is often a relatively straightforward problem and has been well researched. However, segmenting post-operative (post-op) computational tomographic (CT)-scans becomes more ...

  7. Exploring miniature insect brains using micro-CT scanning techniques

    National Research Council Canada - National Science Library

    Smith, Dylan B; Bernhardt, Galina; Raine, Nigel E; Abel, Richard L; Sykes, Dan; Ahmed, Farah; Pedroso, Inti; Gill, Richard J

    2016-01-01

    ...). Here we present a method for accurate imaging and exploration of insect brains that keeps brain tissue free from trauma and in its natural stereo-geometry, and showcase our 3D reconstructions...

  8. Cerebral blood flow and brain atrophy correlated by xenon contrast CT scanning

    Energy Technology Data Exchange (ETDEWEB)

    Kitagawa, Y.; Meyer, J.S.; Tanahashi, N.; Rogers, R.L.; Tachibana, H.; Kandula, P.; Dowell, R.E.; Mortel, K.F.

    1985-11-01

    Correlations between cerebral blood flow (CBF) measured during stable xenon contrast CT scanning and standard CT indices of brain atrophy were investigated in the patients with senile dementia of Alzheimer type, multi-infarct dementia and idiopathic Parkinson's disease. Compared to age-matched normal volunteers, significant correlations were found in patients with idiopathic Parkinson's disease between cortical and subcortical gray matter blood flow and brain atrophy estimated by the ventricular body ratio, and mild to moderate brain atrophy were correlated with stepwise CBF reductions. However, in patients with senile dementia of Alzheimer type and multi-infarct dementia, brain atrophy was not associated with stepwise CBF reductions. Overall correlations between brain atrophy and reduced CBF were weak. Mild degrees of brain atrophy are not always associated with reduced CBF.

  9. Lumbar spine CT scan

    Science.gov (United States)

    CAT scan - lumbar spine; Computed axial tomography scan - lumbar spine; Computed tomography scan - lumbar spine; CT - lower ... The lumbar CT scan is good for evaluating large herniated disks, ... smaller ones. This test can be combined with a myelogram to get ...

  10. Thoracic spine CT scan

    Science.gov (United States)

    CAT scan - thoracic spine; Computed axial tomography scan - thoracic spine; Computed tomography scan - thoracic spine; CT scan - ... Philadelphia, PA: Elsevier Mosby; 2013:chap 44. US Food and Drug Administration. Computed tomography (CT). Updated August ...

  11. Body CT (CAT Scan)

    Science.gov (United States)

    ... Professions Site Index A-Z Computed Tomography (CT) - Body Computed tomography (CT) of the body uses special ... the Body? What is CT Scanning of the Body? Computed tomography, more commonly known as a CT ...

  12. Prevalence of incidental findings in paranasal sinus in brain and orbital CT scans in pediatric patients

    Directory of Open Access Journals (Sweden)

    Adriano Ferreira da Silva

    2011-09-01

    Full Text Available In emergency services a significant amount of pediatric patients undergoa brain or orbit CT scans for suspicion other than sinusitis. Assuming thispremise, this study was held to show the incidental findings of the paranasalsinuses of children with nonspecific symptoms such as fever, headache andvomiting that underwent brain or orbits CT scans, without the initial suspicion of sinusitis. In a retrospective study, we evaluated 70 CT scans of the brainand orbits of children between 0 and 12 years. The incidental findings of theparanasal sinuses occurred in 32 cases (45.7%. Mucosal thickening was themost common incidental finding, being observed in 35% of patients, followed bycomplete opacification observed in 28% of cases and incomplete opacificationobserved in 28% of patients. Bilateral involvement occurred in 78% patients.The sinuses most frequently affected were the maxillary sinus followed byethmoid sinuses. The abnormalities were more severe in children under theage of three years. The prevalence of incidental tomographic abnormalities inpatients without an initial diagnosis of sinusitis is high. The predominance ofthese findings are mild abnormalities.

  13. Arm CT scan

    Science.gov (United States)

    CAT scan - arm; Computed axial tomography scan - arm; Computed tomography scan - arm; CT scan - arm ... stopping.) A computer creates separate images of the arm area, called slices. These images can be stored, ...

  14. MRI and brain spect findings in patients with unilateral temporal lobe epilepsy and normal CT scan

    Directory of Open Access Journals (Sweden)

    P.G. Carrilho

    1994-06-01

    Full Text Available 26 patients with temporal lobe epilepsy clinically documented by several abnormal interictal surface EEGs with typical unitemporal epileptiform activity and a normal CT scan were studied. Interictal99mTC HMPAO brain SPECT and MRI were performed in all subjects. Abnormalities were shown in 61.5% of MRI (n=16 and 65.4% of SPECT (n=17. Hippocampal atrophy associated to a high signal on T2-weighted MRI slices suggesting mesial temporal sclerosis was the main finding (n=12; 75% of abnormal MRI. MRI correlated well to surface EEG in 50% (n=13. There was also a good correlation between MRI and SPECT in 30.7% (n=8. SPECT and EEG were in agreement in 57.7% (n=l5. MRI, SPECT and EEG were congruent in 26.9% (n=7. These results support the usefulness of interictal brain SPECT and MRI in detecting lateralized abnormalities in temporal lobe epilepsy. On the other hand, in two cases, interictal SPECT correlated poorly with surface EEG. This functional method should not be used isolately in the detection of temporal lobe foci. MRI is more useful than CT as a neuroimaging technique in temporal lobe epilepsy. It may detect small structural lesions and mesial temporal lobe sclerosis which are not easily seen with traditional CT scanning.

  15. High prevalence of brain pathology in violent prisoners: a qualitative CT and MRI scan study.

    Science.gov (United States)

    Schiltz, Kolja; Witzel, Joachim G; Bausch-Hölterhoff, Josef; Bogerts, Bernhard

    2013-10-01

    The aim of this study was to determine the frequency and extent of brain anomalies in a large sample of incarcerated violent offenders not previously considered neuropsychiatrically ill, in comparison with non-violent offenders and non-offending controls. MRI and CT brain scans from 287 male prison inmates (162 violent and 125 non-violent) not diagnosed as mentally ill before that were obtained due to headache, vertigo or psychological complaints during imprisonment were assessed and compared to 52 non-criminal controls. Brain scans were rated qualitatively with respect to evidence of structural brain damage. Each case received a semiquantitative rating of "normal" (=0), "questionably abnormal" (=1) or "definitely abnormal" (=2) for the lateral ventricles, frontal/parietal cortex and medial temporal structures bilaterally as well as third ventricle. Overall, offenders displayed a significantly higher rate of morphological abnormality, with the violent offenders scoring significantly higher than non-violent offenders and controls. This difference was statistically detectable for frontal/parietal cortex, medial temporal structures, third ventricle and the left but not the right lateral ventricle. The remarkable prevalence of brain pathology in convicted violent prisoners detectable by neuroradiological routine assessment not only highlights the importance of frontal and temporal structures in the control of social, and specifically of violent behaviour, but also raises questions on the legal culpability of violent offenders with brain abnormalities. The high proportion of undetected presence of structural brain damage emphasizes the need that in violent criminals, the comprehensive routine neuropsychiatric assessment usually performed in routine forensic psychiatric expertises should be complemented with brain imaging.

  16. A longitudinal study of neurocysticercosis through CT scan of the brain

    Directory of Open Access Journals (Sweden)

    Abhiram Chakraborty

    2011-09-01

    Full Text Available Objective: To find out the role of CT scan in the diagnosis of neurocysticercosis (NC and also to get an idea of the nature and extent of this disease in a definite geographical ethnic location. Methods: CT scan of the brain of altogether 4 762 persons residing in a congested area of central Kolkata, was performed between 2004 and 2010, in an imaging centre in central Kolkata (Calcutta, of whom 1 114 (23.39% suspected patients were investigated for NC, having complaints of convulsion (472, headache (272, right sided weakness (98, loss of consciousness (84, left sided weakness (61, abnormal behavior (48, slurring of speech (34, difficulty with keeping balance (33 and dementia (12. Results: NC was detected in 45, 1, 0, 2, 1, 0, 0, 1 and 0, respectively consisting 4.48% (50/1 114 of the suspected cases varying from as low as 2 (in 2006 to as high as 23 (in 2005 in different years indicating this parasitic infection is perennial. The age of patients varied from 6 to 59 years of whom 28 (56% were vegan. We were also able to detect 4 types of lesions viz. calcified lesions (14, small hypodense i.e. vesicle (12, bright central spot i.e. vesicular lesion with central spot (2 and ring enhancement (22. For 3 patients, further imaging investigation (MRI was needed to confirm the diagnosis. We calculated the specificity and sensitivity of CT scan of brain diagnosing NC which was found to be 64% and 100%, respectively. Conclusions: Although, the sample may not be the representatives of the whole community, the findings suggest that cysticercosis is a significant but under-recognized public health concern in Kolkata.

  17. Pediatric CT Scans

    Science.gov (United States)

    The Radiation Epidemiology Branch and collaborators have initiated a retrospective cohort study to evaluate the relationship between radiation exposure from CT scans conducted during childhood and adolescence and the subsequent development of cancer.

  18. Detection of lacunar infarction in brain CT-scans: No evidence of bias from accompanying patient information

    Energy Technology Data Exchange (ETDEWEB)

    Bonke, B.; Knippenberg, F.C.E. van; Duivenvoorden, H.J.; Koudstaal, P.J.; Dijkstra, G.; Hilligersberg, R. van; Kappelle, L.J.

    1989-05-01

    Interobserver agreement in assessing brain CT-scans is, in general, high. The extent, however, to which such agreement is caused by bias through knowledge of other clinical details remains uncertain. The hypothesis that observers are somehow prejudiced before assessing ambiguous, CT-scans in this particular situation was tested. Sixteen neurologists and 16 radiologists volunteered to interpret two ambiguous brain CT-scans, with regard to the presence or absence of a lacunar infarct in the region of the internal capsule. The scans were accompanied by 'patient' information that was or was not suggestive of a stroke. These scans were camouflaged by a variety of other scans, to be assessed in the same way, to mask the purpose of the study. I was assumed that the observers, in their assessments of the scans, would somehow let their ratings of the likelihood of a lacunar infarction in or near the internal capsule be subject to the accompanying information. Results showed lower ratings produced by neurologists (i.e., less likelihood of an infarction) than by radiologists in the majority of all assessments, but no bias by the accompanying information.

  19. Fully-automated computer-assisted method of CT brain scan analysis for the measurement of cerebrospinal fluid spaces and brain absorption density

    Energy Technology Data Exchange (ETDEWEB)

    Baldy, R.E.; Brindley, G.S.; Jacobson, R.R.; Reveley, M.A.; Lishman, W.A.; Ewusi-Mensah, I.; Turner, S.W.

    1986-03-01

    Computer-assisted methods of CT brain scan analysis offer considerable advantages over visual inspection, particularly in research; and several semi-automated methods are currently available. A new computer-assisted program is presented which provides fully automated processing of CT brain scans, depending on ''anatomical knowledge'' of where cerebrospinal fluid (CSF)-containing spaces are likely to lie. After identifying these regions of interest quantitative estimates are then provided of CSF content in each slice in cisterns, ventricles, Sylvian fissure and interhemispheric fissure. Separate measures are also provided of mean brain density in each slice. These estimates can be summated to provide total ventricular and total brain volumes. The program shows a high correlation with measures derived from mechanical planimetry and visual grading procedures, also when tested against a phantom brain of known ventricular volume. The advantages and limitations of the present program are discussed.

  20. Prognostic value of somatosensory-evoked potentials and CT scan evaluation in acute traumatic brain injury.

    Science.gov (United States)

    Bosco, Enrico; Zanatta, Paolo; Ponzin, Diego; Marton, Elisabetta; Feletti, Alberto; Scarpa, Bruno; Longatti, Pierluigi; Paolin, Adolfo

    2014-10-01

    The aim of this study is to assess whether a complete analysis of all early cortical somatosensory-evoked potentials (SEPs) components and computed tomography (CT) scan features can provide a better prognostic measure than the early cortical component N20/P25 alone, in patients with severe head injury. We studied 81 consecutive patients admitted to intensive care unit with diagnosis of severe head injury. All patients underwent neurophysiological assessment with SEPs and electroencephalography within the first 6 days after trauma. The marginal effect of each variable on Glasgow Outcome Scale score was evaluated by using univariate measures of association. We fit a cumulative logit model by maximum likelihood, and the partial effect of each variable was assessed by likelihood ratio test. We performed variable selection by forward stepwise, according to the Akaike information criterion. Our final cumulative logit model including SEPs primary complex (pN20/fP20/cP22), SEPs middle latency (N30/P45/N60), and CT scan hypodensity values showed a significantly increased predictive power of Glasgow Outcome Scale, compared with pN20 alone (P<0.0001). Statistical analysis revealed a highly significant (P<0.0001) improvement in outcome prediction when the model includes a pool of amplitudes and latencies referred to different early-evoked components pN20, pP25, fP20, cP22, N30, P45, and N60, associated to CT scan hypodensity values, compared with the use of the cortical parietal N20/P25 alone.

  1. Assessment of Brain absorbed X-ray dose during CT- Scan using ImPACT software in Tehran Univeristy hospitals

    Directory of Open Access Journals (Sweden)

    Khalilpour M

    2009-07-01

    Full Text Available "n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 st1":*{behavior:url(#ieooui } /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: CT scan was first introduced into clinical practice in 1972, and since then has grown into one of the predominant diagnostic procedures. In 1998, the UK National Radiological Protection Board reported that 20% of the national collective dose from medical X-ray examinations derived from CT-scans, although it represented only 2% of all X- ray examinations the aim of this study was to determine the X-ray dosage received by patients in brain CT scan."n"n Methods: In this work, we have estimated patient dose arising from CT examination of brain in five hospitals in Tehran. Organ and effective doses were estimated for 150 patients who underwent CT examination of brain. "ImPACT" version 0.99v was used to estimate organ and effective dose. Brain examinations were performed with fixed Kvp, mAs and T (slice thickness for each scanner. "n"n Results: Patients, who were scanned by CT of emam Khomeini center (Toshiba Xvision /EX Scanner, received maximum organ dose (brain and minimum organ dose was delivered to patients who were scanned by CT of amir alam center (Toshiba Xvision /EX Scanner. Maximum effective dose was 1.7 mSv acquired in this study for emam Khomeini haspital, smaller than

  2. The use of brain CT Scan in craniocerebral trauma with Glasgow coma scale scores of 13 – 15 in Dr. Cipto Mangunkusumo Hospital 1999-2001

    Directory of Open Access Journals (Sweden)

    Jofizal Jannis

    2004-09-01

    Full Text Available There is still a controversy among the neurologists whether brain CT scan must be performed on the mild head trauma patients. This study was executed to find out the correlation between the brain CT scan image findings and its clinical impairment among the mild head trauma patients with Glasgow coma scale (GCS score of 13 to 15. The study was a retrospective study by analyzing the uniform medical records of the head trauma patients hospitalized at the Neurology ward of Dr. Cipto Mangunkusumo Hospital within the period of 1999 to 2001. During that period 1,663 patients were hospitalized due to head trauma, and 1,166 of them (70.1 % were suffered from mild head trauma patients with GCS score of 13-15. Among those with brain CT scan examinations (N: 271, the neurological abnormalities were found on 144 (53.1% of patients, consisted of cerebral edema (11,4%, intracerebral hemorrhage (5.5%, epidural hemorrhage (16.2%, subdural hemorrhage (18.1%, subarachnoid hemorrhage (5.5%, and combination (13.8%. The further analysis showed that cranial nerves disturbance, amnesia, loss of conciousness for more than 10 minutes, and vomiting are significantly correlated to the brain CT scan abnormality. Combination of the above four clinical signs and symptoms have sensitivity of 90 % in predicting brain insults. This findings may be used as a simple set of clinical criteria for identifying mild head trauma patients who need undergo CT scan examination. (Med J Indones 2004; 13: 156-60 Keywords: mild head injury, brain CT scan

  3. How to interpret an unenhanced CT Brain scan. Part 1: Basic principles of Computed Tomography and relevant neuroanatomy

    Directory of Open Access Journals (Sweden)

    Thomas Osborne

    2016-08-01

    Full Text Available The aim of this article is to: Cover the basics of Computed Tomography (CT Brain imaging. Review relevant CT neuroanatomy. A CT image is produced by firing x-rays at a moving object which is then detected by an array of rotating detectors (Figure 1. The detected x-rays are then converted into a computerised signal which is used to produce a series of cross sectional images.

  4. Pelvic CT scan

    Science.gov (United States)

    ... bones. Single CT images are called slices. The images are stored on a computer, viewed on a monitor, or printed on film. Three-dimensional models of the body area can be created by stacking the slices ...

  5. CT scans in psychiatric patients -

    African Journals Online (AJOL)

    into the aetiology and long-term structural abnormalities in the brains ot patients with schizophrenia, mood disorders, metabolic and neurological disorders ot the brain. However, the place at. CT in clinical psychiatry is less clear. Disorders ot the central nervous system resulting trom trauma, intracranial haemorrhage,.

  6. Incidence of Brain Metastases on Follow-up18F-FDG PET/CT Scans of Non-Small Cell Lung Cancer Patients: Should We Include the Brain?

    Science.gov (United States)

    Nia, Emily S; Garland, Linda L; Eshghi, Naghmehossadat; Nia, Benjamin B; Avery, Ryan J; Kuo, Phillip H

    2017-09-01

    The brain is the most common site of distant metastasis from lung cancer. Thus, MRI of the brain at initial staging is routinely performed, but if this examination is negative a follow-up examination is often not performed. This study evaluates the incidence of asymptomatic brain metastases in non-small cell lung cancer patients detected on follow-up 18 F-FDG PET/CT scans. Methods: In this Institutional Review Board-approved retrospective review, all vertex to thigh 18 F-FDG PET/CT scans in patients with all subtypes of lung cancer from August 2014 to August 2016 were reviewed. A total of 1,175 18 F-FDG PET/CT examinations in 363 patients were reviewed. Exclusion criteria included brain metastases on initial staging, histologic subtype of small-cell lung cancer, and no follow-up 18 F-FDG PET/CT examinations. After our exclusion criteria were applied, a total of 809 follow-up 18 F-FDG PET/CT scans in 227 patients were included in the final analysis. The original report of each 18 F-FDG PET/CT study was reviewed for the finding of brain metastasis. The finding of a new brain metastasis prompted a brain MRI, which was reviewed to determine the accuracy of the 18 F-FDG PET/CT. Results: Five of 227 patients with 809 follow-up 18 F-FDG PET/CT scans reviewed were found to have incidental brain metastases. The mean age of the patients with incidental brain metastasis was 68 y (range, 60-77 y). The mean time from initial diagnosis to time of detection of incidental brain metastasis was 36 mo (range, 15-66 mo). When MRI was used as the gold standard, our false-positive rate was zero. Conclusion: By including the entire head during follow-up 18 F-FDG PET/CT scans of patients with non-small cell lung cancer, brain metastases can be detected earlier while still asymptomatic. But, given the additional scan time, radiation, and low incidence of new brain metastases in asymptomatic patients, the cost-to-benefit ratio should be weighed by each institution. © 2017 by the Society of

  7. CT FINDINGS IN HEAD SCANS AT MOI TEACHING AND ...

    African Journals Online (AJOL)

    1998-02-20

    Feb 20, 1998 ... ionic contrast media which are less toxic than ionic media are recommended in brain CT(15). CT scan guided biopsies are a safe and accurate way to obtain brain tissue specimens for pathological diagnosis in selected cases(l6). Assault and motor vehicle accidents were the major causes of head trauma.

  8. Female patients dosimetry in brain exams with PET/CT scan for diagnosis of Mild Cognitive Impairment (MCI)

    Energy Technology Data Exchange (ETDEWEB)

    Santana, P.C.; Mamede, M.; Carvalho, F.M.V., E-mail: pridili@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Mourao, A.P., E-mail: apratabhz@gmail.com [Centro Federal de Educacao Tecnologica, Belo Horionte, MG (Brazil). Dept. de Engenharia Eletrica; Oliveira, P.M.C.; Silva, T.A. da, E-mail: pmco@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    Dementia affects over 35 million people worldwide, with strong personal, social and financial impacts. Alzheimer's disease is the most common form of dementia, accounting for 60-70% of cases, affecting mostly females. Recent technological innovations, using methods of anatomical and functional neuroimaging, with particular emphasis on PET / CT (positron emission tomography with computed tomography associated), have shown excellent prospects for early diagnosis of Alzheimer's disease represented by Mild Cognitive Impairment (MCI). The use of PET / CT helps diagnosis, but the patients effective dose is higher and directly dependent on the radiopharmaceutical activity and the computed tomographic (CT) protocol used. The aim of this study was evaluated the organs absorbed doses and effective doses in 59 female patients undergoing the PET/CT diagnostic technique. For the measurements of radiation levels from the CT was used TLD100 (LiF:Mg, Ti) Rod detectors inserted in Alderson Randon ® anthropomorphic phantom, which simulates a female pattern, of 155 cm and weight 50 kg, subjected to the same clinical protocol of acquiring patients images. The effective dose resulting from the radiopharmaceutical injected activity was estimated by ICRP106 model using the weight of the patients undergoing to the procedure. The average effective dose due was (7.65 ± 2.22) mSv. The effective dose contribution to the brain and the thyroid due to CT were (2.21 ± 0.38) and (0.72 ± 0.14) mSv, respectively. The use of CT optimized protocols can assist in reducing the dose in this type of procedure. (author)

  9. Evaluation of Criteria for Requesting Brain CT Scan before Performing Lumbar Puncture for the Children Suspicious to Meningitis in Rasul Akram Hospital, Tehran

    Directory of Open Access Journals (Sweden)

    A.R. Nateghian

    2005-04-01

    Full Text Available Lumbar puncture (LP is the only way to diagnose meningitis, however some concerning points regarding its complication especially brain herniation are usually noted. Several factors including difficulties of neurologic examination especially in infants, absence of cooperation when performing the LP, incorrect myths and legal issues as well as unavailability of CT equipment , X-ray exposure and charges; makes evaluation of such requests reasonable .One hundred infants and children, 2 months to 12 years old who were suspicious to have meningitis were enrolled in this cross-sectional, descriptive study. Two groups were formed based on requesting a B.CT (Brain CT scan before LP or performing the procedure directly. Demographic and clinical parameters were analyzed among two groups using a questionnaire and CT results were recorded. Chi-square test was used for statistical analysis; P value<0.05 was considered as significant.B.CT was requested for 21 patients (case group in which the results led to postponing the procedure in 14%( 3 of cases. Toxic appearance, poor general condition, bulging fontanel and impaired consciousness (GCS score<8 were significantly related to such a decision making. There was also a trend toward ordering B.CT for those patients with recent cardiopulmonary arrest, focal signs, papilledema, hemiparesis and bradycardia. Two cases of brain herniation were identified in the control group, both had severe irritability and projectile vomiting at presentation.According to other studies, severe impairment of consciousness and presence of focal signs and symptoms are acceptable criteria for such a request, however ordering B.CT solely based on general condition or presence of a bulge fontanel seems to be unreasonable for which we couldn’t identify any supportive study. Larger scale studies considering the pediatric differential diagnosis and characteristics are required to generate proper, scientific and supportive protocols in this

  10. Optimal scan timing for artery-vein separation at whole-brain CT angiography using a 320-row MDCT volume scanner.

    Science.gov (United States)

    Shirasaka, Takashi; Hiwatashi, Akio; Yamashita, Koji; Kondo, Masatoshi; Hamasaki, Hiroshi; Shimomiya, Yamato; Nakamura, Yasuhiko; Funama, Yoshinori; Honda, Hiroshi

    2017-02-01

    A 320-row multidetector CT (MDCT) is expected for a good artery-vein separation in terms of temporal resolution. However, a shortened scan duration may lead to insufficient vascular enhancement. We assessed the optimal scan timing for the artery-vein separation at whole-brain CT angiography (CTA) when bolus tracking was used at 320-row MDCT. We analyzed 60 patients, who underwent whole-brain four-dimensional CTA. Difference in CT attenuation between the internal carotid artery (ICA) and the superior sagittal sinus (Datt) was calculated in each phase. Using a visual evaluation score for the depiction of arteries and veins, we calculated the difference between the mean score for the intracranial arteries and the mean score for the veins (Dscore). We assessed the time at which the maximum Datt and Dscore were simultaneously observed. The maximum Datt was observed at 6.0 s and 8.0 s in the arterial-dominant phase and at 16.0 s and 18.0 s in the venous-dominant phase after the contrast media arrival time at the ICA (Taa). The maximum Dscore was observed at 6.0 s and 8.0 s in the arterial-dominant phase and at 16.0 s in the venous-dominant phase after the Taa. There were no statistically significant differences in Datt (p = 0.375) or Dscore (p = 0.139) between these scan timings. The optimal scan timing for artery-vein separation at whole-brain CTA was 6.0 s or 8.0 s for the arteries and 16.0 s for the veins after the Taa. Advances in knowledge: Optimal scan timing allowed us to visualize intracranial arteries or veins with minimal superimposition.

  11. Subject-specific bone attenuation correction for brain PET/MR: can ZTE-MRI substitute CT scan accurately?

    Science.gov (United States)

    Khalifé, Maya; Fernandez, Brice; Jaubert, Olivier; Soussan, Michael; Brulon, Vincent; Buvat, Irène; Comtat, Claude

    2017-10-01

    In brain PET/MR applications, accurate attenuation maps are required for accurate PET image quantification. An implemented attenuation correction (AC) method for brain imaging is the single-atlas approach that estimates an AC map from an averaged CT template. As an alternative, we propose to use a zero echo time (ZTE) pulse sequence to segment bone, air and soft tissue. A linear relationship between histogram normalized ZTE intensity and measured CT density in Hounsfield units (HU ) in bone has been established thanks to a CT-MR database of 16 patients. Continuous AC maps were computed based on the segmented ZTE by setting a fixed linear attenuation coefficient (LAC) to air and soft tissue and by using the linear relationship to generate continuous μ values for the bone. Additionally, for the purpose of comparison, four other AC maps were generated: a ZTE derived AC map with a fixed LAC for the bone, an AC map based on the single-atlas approach as provided by the PET/MR manufacturer, a soft-tissue only AC map and, finally, the CT derived attenuation map used as the gold standard (CTAC). All these AC maps were used with different levels of smoothing for PET image reconstruction with and without time-of-flight (TOF). The subject-specific AC map generated by combining ZTE-based segmentation and linear scaling of the normalized ZTE signal into HU was found to be a good substitute for the measured CTAC map in brain PET/MR when used with a Gaussian smoothing kernel of 4~mm corresponding to the PET scanner intrinsic resolution. As expected TOF reduces AC error regardless of the AC method. The continuous ZTE-AC performed better than the other alternative MR derived AC methods, reducing the quantification error between the MRAC corrected PET image and the reference CTAC corrected PET image.

  12. Increased frequency of brain pathology in inmates of a high-security forensic institution: a qualitative CT and MRI scan study.

    Science.gov (United States)

    Witzel, Joachim G; Bogerts, Bernhard; Schiltz, Kolja

    2016-09-01

    This study aimed to assess whether brain pathology might be more abundant in forensic inpatients in a high-security setting than in non-criminal individuals. By using a previously used reliable approach, we explored the frequency and extent of brain pathology in a large group of institutionalized offenders who had not previously been considered to be suffering from structural brain damage and compare it to healthy, non-offending subjects. MRI and CT brain scans from 148 male inpatients of a high-security mental health institution (offense type: 51 sex, 80 violent, 9 arson, and 8 nonviolent) that were obtained due to headache, vertigo, or psychological complaints during imprisonment were assessed and compared to 52 non-criminal healthy controls. Brain scans were assessed qualitatively with respect to evidence of structural brain damage. Each case received a semiquantitative rating of "normal" (=0), "questionably abnormal" (=1), or "definitely abnormal" (=2) for the lateral ventricles, frontal/parietal cortex, and medial temporal structures bilaterally as well as third ventricle. Forensic inpatients displayed signs of brain damage to a significantly higher degree than healthy controls (p brain regions categorized as definitely abnormal than the non-criminal controls. Within the forensic inpatients, offense type groups did not significantly differ in brain pathology. The astonishingly high prevalence of brain pathology in institutionalized inmates of a high-security mental health institution who previously had not been considered to be suffering from an organic brain syndrome raises questions on whether such neuroradiological assessment might be considered as a routine procedure in newly admitted patients. Furthermore, it highlights that organic changes, detectable under clinical routine conditions, may play a role in the development of legally relevant behavioral disturbances which might be underestimated.

  13. A database for estimating organ dose for coronary angiography and brain perfusion CT scans for arbitrary spectra and angular tube current modulation

    Energy Technology Data Exchange (ETDEWEB)

    Rupcich, Franco; Badal, Andreu; Kyprianou, Iacovos; Schmidt, Taly Gilat [Department of Biomedical Engineering, Marquette University, Milwaukee, Wisconsin 53233 (United States); Division of Imaging and Applied Mathematics (OSEL/CDRH), US Food and Drug Administration, Silver Spring, Maryland 20905 (United States); Department of Biomedical Engineering, Marquette University, Milwaukee, Wisconsin 53233 (United States)

    2012-09-15

    Purpose: The purpose of this study was to develop a database for estimating organ dose in a voxelized patient model for coronary angiography and brain perfusion CT acquisitions with any spectra and angular tube current modulation setting. The database enables organ dose estimation for existing and novel acquisition techniques without requiring Monte Carlo simulations. Methods: The study simulated transport of monoenergetic photons between 5 and 150 keV for 1000 projections over 360 Degree-Sign through anthropomorphic voxelized female chest and head (0 Degree-Sign and 30 Degree-Sign tilt) phantoms and standard head and body CTDI dosimetry cylinders. The simulations resulted in tables of normalized dose deposition for several radiosensitive organs quantifying the organ dose per emitted photon for each incident photon energy and projection angle for coronary angiography and brain perfusion acquisitions. The values in a table can be multiplied by an incident spectrum and number of photons at each projection angle and then summed across all energies and angles to estimate total organ dose. Scanner-specific organ dose may be approximated by normalizing the database-estimated organ dose by the database-estimated CTDI{sub vol} and multiplying by a physical CTDI{sub vol} measurement. Two examples are provided demonstrating how to use the tables to estimate relative organ dose. In the first, the change in breast and lung dose during coronary angiography CT scans is calculated for reduced kVp, angular tube current modulation, and partial angle scanning protocols relative to a reference protocol. In the second example, the change in dose to the eye lens is calculated for a brain perfusion CT acquisition in which the gantry is tilted 30 Degree-Sign relative to a nontilted scan. Results: Our database provides tables of normalized dose deposition for several radiosensitive organs irradiated during coronary angiography and brain perfusion CT scans. Validation results indicate

  14. Clinical values of CT and dynamic CT in brain infarction

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Soo Il; Jang, Do; Seo, Eun Joo; Sohn, Myung Hee; Choi, Ki Chul [Chonbuk National University College of Medicine, Jeonju (Korea, Republic of)

    1985-04-15

    With the advent of faster scan time and new computer program, a scanning technique called 'dynamic computed tomography' has become possible. Dynamic computed tomography consisted of performing multiple rapid sequence scans after injection of contrast material. The authors have evaluated the clinical usefulness of computed tomography and dynamic computed tomography of 93 patients with brain infarction and/or ischemia during the period of 17 months from April 1983 to August 1984 in Department of Radiology, Chonbuk National University Hospital. The results were as follows; 1. The age distribution ranged from 18 years to 78 years. Among them the most common age group was between 50 years and 59 years (40.9%). 2. The sites of brain infarction were cerebral lobes (63 cases,68), basal ganglia (15 cases, 16.1%) and multiple sites (6 cases, 6.4%). The common affected site was middle cerebral artery territories. 3. The contrast enhancement of acute infarction was noted in 14 cases (17.5%) which occurred commonly between 3 days and 2 weeks from ictus. 4. The patterns of time-density curve in brain infarction and/or ischemia were as follow: a. Depression of slow wash-in phase was 20 cases (59%). b. Lower peak concentration was 17 cases (50%). c. Lower and delayed peak concentration was 7 cases (21%). d. No definite peak concentration was 6 cases (18%). First three patterns of time-density curve were thought as relatively characteristic curve of brain infarction and/or ischemia. 5. Two cases that showed negative findings on precontrast CT scan appeared to be positive findings as hypodensity on postcontrast CT scan and were confirmed as brain infarction by dynamic CT. 6. The diagnostic entity of dynamic CT scan were as follows; a. large artery thrombotic infarction were 23 cases (58%). b. lacnar infarction were 6 cases (15%). c. ischemia were 5 cases (13%). d. normal were 5 cases (13%). In six cases of lacunar infarction which was double hypodensity on pre

  15. [Preoperative CT Scan in middle ear cholesteatoma].

    Science.gov (United States)

    Sethom, Anissa; Akkari, Khemaies; Dridi, Inès; Tmimi, S; Mardassi, Ali; Benzarti, Sonia; Miled, Imed; Chebbi, Mohamed Kamel

    2011-03-01

    To compare preoperative CT scan finding and per-operative lesions in patients operated for middle ear cholesteatoma, A retrospective study including 60 patients with cholesteatoma otitis diagnosed and treated within a period of 5 years, from 2001 to 2005, at ENT department of Military Hospital of Tunis. All patients had computed tomography of the middle and inner ear. High resolution CT scan imaging was performed using millimetric incidences (3 to 5 millimetres). All patients had surgical removal of their cholesteatoma using down wall technic. We evaluated sensitivity, specificity and predictive value of CT-scan comparing otitic damages and CT finding, in order to examine the real contribution of computed tomography in cholesteatoma otitis. CT scan analysis of middle ear bone structures shows satisfaction (with 83% of sensibility). The rate of sensibility decrease (63%) for the tympanic raff. Predictive value of CT scan for the diagnosis of cholesteatoma was low. However, we have noticed an excellent sensibility in the analysis of ossicular damages (90%). Comparative frontal incidence seems to be less sensible for the detection of facial nerve lesions (42%). But when evident on CT scan findings, lesions of facial nerve were usually observed preoperatively (spécificity 78%). Predictive value of computed tomography for the diagnosis of perilymphatic fistulae (FL) was low. In fact, CT scan imaging have showed FL only for four patients among eight. Best results can be obtained if using inframillimetric incidences with performed high resolution computed tomography. Preoperative computed tomography is necessary for the diagnosis and the evaluation of chronic middle ear cholesteatoma in order to show extending lesion and to detect complications. This CT analysis and surgical correlation have showed that sensibility, specificity and predictive value of CT-scan depend on the anatomic structure implicated in cholesteatoma damages.

  16. Congenital cystic eye-A case report with CT scan

    Directory of Open Access Journals (Sweden)

    Pillai A

    1987-01-01

    Full Text Available A case of Congential cystic eye in a two month old girl is reported. This rare condition is recognised at birth as a large orbital mass in place of the normal eye. This is perhaps the first reported case with a CT Scan. The CT appearance suggests that the defect in embryogenesis is not confined to the optic vesicle but involves other parts of the brain also.

  17. Contextual Analysis of CT Scanned Pig Carcasses

    DEFF Research Database (Denmark)

    Lyckegaard, Allan; Larsen, Rasmus; Christensen, Lars Bager

    2006-01-01

    Knowledge of the weight of tissue types in pig carcasses is generally only available after manual dissection. The use of computed tomography (CT) has demonstrated to be a promising approach to gain knowledge on the lean meat weight (Romvari, 2005), but less effort has been put into gaining...... not consider the spatial context in CT scan. Applying contextual methods from the field of image analysis we hope to make a virtual dissection of pig carcasses....

  18. CT scan of bacterial and aseptic meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Takemoto, Kazumasa; Saiwai, Shigeo; Tamaoka, Koichi (Kobe Central Municipal Hospital (Japan))

    1983-01-01

    CT scans of the patients with aseptic and bacterial meningitis were reviewed and compared to previous reports. In aseptic meningitis, no abnormal CT findings were observed. In bacterial meningitis, CT findings were ventricular dilatation, subdural fluid collection, parenchymal low density, intracerebral hematoma and meningeal enhancement after contrast injection. Three patients among 48 suffered from status epileptics during the course of the illness. All of the 3 patients developed parenchymal inhomogeneous low density and progressive ventricular dilatation which did not improve after ventricular peritoneal shunt surgery. We believe that these changes are most likely due to hypoxic hypoxemia during epileptic seizure and meningitis itself seems to play a little role.

  19. Serial CT scans and Menkes' kinky hair disease

    Energy Technology Data Exchange (ETDEWEB)

    Nakada, Eizo; Kameyama, Junji; Yoshimitsu, Hajime; Mori, Mikio; Tanaka, Mutsuo; Yoshimitsu, Kazunori.

    1988-02-01

    Menkes' kinky hair disease is a sex-linked recessive disorder of copper metabolism, characterized by progressive psychomotor deterioration, seizures, and peculiar hair structure. We examined serial CT scans of patients with this disease. A 2,210-g male infant was delivered after an uneventful gestation of 36 weeks. His one-minute Apgar score was 9. His uncle had died at 1 year of age. His first cousin was also diagnosed as having Menkes' kinky hair disease when our patient was 2 years old. Shortly after birth he had mild respiratory distress. At 5 days of age, he developed setting-sun signs. The first CT scan, at 10 days of age, revealed mild posterior fossa hemorrhages. At 3 months of age, myoclonic seizures began, and the CT scan revealed subdural effusion and mild brain atrophy. The seizures were controllable by using phenobarbital, valproic acid, and nitrazepam. He did not follow light or a fixate, but the fundi were normal. He was diffusely hypotonic. At 9 months of age, the seizures became uncontrollable. The CT scans at 15 and 31 months of age showed subdural hemorrhage and/or brain atrophy. At 15 months of age, the serum copper level was 42 ..mu.. g/dl, while the serum ceruloplasmin level was 3.2 mg/dl. He exhibited severe developmental failure. At 4 years of age, he died.

  20. Left Ventricular Pseudoaneurysm Found by CT Scan

    OpenAIRE

    Hirose, Hitoshi; Matsunaga, Iwao; Strong, Michael D

    2008-01-01

    A 62-year-old male with a previous coronary artery bypass grafting underwent CT scan for evaluation of left epigastric pain. Findings showed a large left ventricular pseudoaneurysm, which was subsequently confirmed by left ventriculogram. The pseudoaneurysm was successfully repaired surgically.

  1. MR to CT registration of brains using image synthesis

    Science.gov (United States)

    Roy, Snehashis; Carass, Aaron; Jog, Amod; Prince, Jerry L.; Lee, Junghoon

    2014-03-01

    Computed tomography (CT) is the preferred imaging modality for patient dose calculation for radiation therapy. Magnetic resonance (MR) imaging (MRI) is used along with CT to identify brain structures due to its superior soft tissue contrast. Registration of MR and CT is necessary for accurate delineation of the tumor and other structures, and is critical in radiotherapy planning. Mutual information (MI) or its variants are typically used as a similarity metric to register MRI to CT. However, unlike CT, MRI intensity does not have an accepted calibrated intensity scale. Therefore, MI-based MR-CT registration may vary from scan to scan as MI depends on the joint histogram of the images. In this paper, we propose a fully automatic framework for MR-CT registration by synthesizing a synthetic CT image from MRI using a co-registered pair of MR and CT images as an atlas. Patches of the subject MRI are matched to the atlas and the synthetic CT patches are estimated in a probabilistic framework. The synthetic CT is registered to the original CT using a deformable registration and the computed deformation is applied to the MRI. In contrast to most existing methods, we do not need any manual intervention such as picking landmarks or regions of interests. The proposed method was validated on ten brain cancer patient cases, showing 25% improvement in MI and correlation between MR and CT images after registration compared to state-of-the-art registration methods.

  2. MR to CT Registration of Brains using Image Synthesis.

    Science.gov (United States)

    Roy, Snehashis; Carass, Aaron; Jog, Amod; Prince, Jerry L; Lee, Junghoon

    2014-03-21

    Computed tomography (CT) is the standard imaging modality for patient dose calculation for radiation therapy. Magnetic resonance (MR) imaging (MRI) is used along with CT to identify brain structures due to its superior soft tissue contrast. Registration of MR and CT is necessary for accurate delineation of the tumor and other structures, and is critical in radiotherapy planning. Mutual information (MI) or its variants are typically used as a similarity metric to register MRI to CT. However, unlike CT, MRI intensity does not have an accepted calibrated intensity scale. Therefore, MI-based MR-CT registration may vary from scan to scan as MI depends on the joint histogram of the images. In this paper, we propose a fully automatic framework for MR-CT registration by synthesizing a synthetic CT image from MRI using a co-registered pair of MR and CT images as an atlas. Patches of the subject MRI are matched to the atlas and the synthetic CT patches are estimated in a probabilistic framework. The synthetic CT is registered to the original CT using a deformable registration and the computed deformation is applied to the MRI. In contrast to most existing methods, we do not need any manual intervention such as picking landmarks or regions of interests. The proposed method was validated on ten brain cancer patient cases, showing 25% improvement in MI and correlation between MR and CT images after registration compared to state-of-the-art registration methods.

  3. Computerized tomography (CT) in patients with head injuries. Relation between CT scans and clinical findings in 96 patients

    Energy Technology Data Exchange (ETDEWEB)

    Espersen, J.O.; Petersen, O.F. (Aarhus Univ. (Denmark). Dept. of Neurosurgery GF; Aarhus Univ. (Denmark). Dept. Neuroradiology P)

    1981-01-01

    In a retrospective series of 144 patients with cranial trauma admitted to the Department of Neurosurgery, 96 were initially examined by CT. The initial clinical assessment, operative findings, if any, and the clinical course were compared to the results of the primary CT scan. In patients presenting lateralizing deficits, 49% had lesions on the expected side, and 23% on the opposite side. Thirty-one per cent of brain stem affected patients had a supratentorial mass lesion requiring craniotomy. Three decerebrate patients who died had an initially normal CT scan. Thirty craniotomies were performed on the basis of the CT scans, and six cases deviated from the expected, but no case showed a false positive indication for surgery. The final diagnosis was in accordance with the initial clinical diagnosis, and with the initial CT scan in 44% and 84%, respectively, of all cases.

  4. Treatment of alzheimer disease with CT scans - a case report

    Energy Technology Data Exchange (ETDEWEB)

    Cuttler, J.M. [Cuttler & Associates Inc., Vaughan, Ontario (Canada); Moore, E.R. [Dow Chemical Co., Midland, MI (United States); Hosfeld, V.D. [MidMichigan Health, Midland, MI (United States); Nadolski, D.L. [Midland Internal Medicine Associates PC, Midland, MI (United States)

    2016-03-15

    Alzheimer disease (AD) primarily affects older adults. This neurodegenerative disorder is the most common cause of dementia and is a leading source of their morbidity and mortality. U.S. patient care costs are about 200 billion dollars and will more than double by 2040. This case report describes the remarkable improvement of an advanced AD patient in hospice, who received five CT scans of the brain, about 40 mGy each, over a period of three months. The mechanism appears to be radiation-induced up-regulation of the patient's adaptive protection systems against AD, which partially restored cognition, memory, speech, movement, and appetite. (author)

  5. Xenon contrast CT-CBF scanning of the brain differentiates normal age-related changes from multi-infarct dementia and senile dementia of Alzheimer type

    Energy Technology Data Exchange (ETDEWEB)

    Tachibana, H.; Meyer, J.S.; Okayasu, H.; Shaw, T.G.; Kandula, P.; Rogers, R.L.

    1984-07-01

    Local cerebral blood flow (LCBF) and partition coefficients (L lambda) were measured during inhalation of stable xenon gas with serial CT scanning among normal volunteers (N . 15), individuals with multi-infarct dementia (MID, N . 10), and persons with senile dementia of Alzheimer type (SDAT, N . 8). Mean gray matter flow values were reduced in both MID and SDAT. Age-related declines in LCBF values in normals were marked in frontal cortex and basal ganglia. LCBF values were decreased beyond normals in frontal and temporal cortices and thalamus in MID and SDAT, in basal ganglia only in MID. Unlike SDAT and age-matched normals, L lambda values were reduced in fronto-temporal cortex and thalamus in MID. Multifocal nature of lesions in MID was apparent. Coefficients of variation for LCBFs were greater in MID compared with SDAT and/or age-matched normals.

  6. Full-Body CT Scans - What You Need to Know

    Science.gov (United States)

    ... Procedures Medical Imaging Medical X-ray Imaging Full-Body CT Scans - What You Need to Know Share ... if you are thinking of having a whole-body screening: Whole-body CT screening has not been ...

  7. ROLE OF CT SCAN IN PARTIAL SEIZURES IN CHILDREN.

    Science.gov (United States)

    Kanitkar, M; Purkayastha, S B; Deshpande, N D

    1994-01-01

    50 consecutive cases of partial seizures hospitalised over a period of 2 years, were studied. CT Scans were done once at presentation and thereafter cases were followed up with repeat CT scans to evaluate treatment response wherever a treatable cause was found. CT scan diagnosis was correlated with clinical signs and other baseline investigations including an EEG. CT scan abnormality was detected in 66% cases. Single or multiple tuberculomas were noted in 24% cases, cortical atrophy in 14% cases, focal calcification in 10%, haemorrhage in 3% and subdural effusions in 2%. With positive clinical signs, 81% of CT scans were abnormal. 20% of patients with partial seizures having no clinical signs and normal base line investigations including an EEG, had a CT scan abnormality mainly a tuberculoma.

  8. Differential Aging Signals in Abdominal CT Scans.

    Science.gov (United States)

    Orlov, Nikita V; Makrogiannis, Sokratis; Ferrucci, Luigi; Goldberg, Ilya G

    2017-12-01

    Changes in the composition of body tissues are major aging phenotypes, but they have been difficult to study in depth. Here we describe age-related change in abdominal tissues observable in computed tomography (CT) scans. We used pattern recognition and machine learning to detect and quantify these changes in a model-agnostic fashion. CT scans of abdominal L4 sections were obtained from Baltimore Longitudinal Study of Aging (BLSA) participants. Age-related change in the constituent tissues were determined by training machine classifiers to differentiate age groups within male and female strata ("Younger" at 50-70 years old vs "Older" at 80-99 years old). The accuracy achieved by the classifiers in differentiating the age cohorts was used as a surrogate measure of the aging signal in the different tissues. The highest accuracy for discriminating age differences was 0.76 and 0.72 for males and females, respectively. The classification accuracy was 0.79 and 0.71 for adipose tissue, 0.70 and 0.68 for soft tissue, and 0.65 and 0.64 for bone. Using image data from a large sample of well-characterized pool of participants dispersed over a wide age range, we explored age-related differences in gross morphology and texture of abdominal tissues. This technology is advantageous for tracking effects of biological aging and predicting adverse outcomes when compared to the traditional use of specific molecular biomarkers. Application of pattern recognition and machine learning as a tool for analyzing medical images may provide much needed insight into tissue changes occurring with aging and, further, connect these changes with their metabolic and functional consequences. Published by Elsevier Inc.

  9. Patient dose estimation from CT scans at the Mexican National Neurology and Neurosurgery Institute

    Energy Technology Data Exchange (ETDEWEB)

    Alva-Sánchez, Héctor, E-mail: halva@ciencias.unam.mx [Unidad de Imagen Molecular PET/CT, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, Insurgentes Sur 3877 Col. La Fama, 14269, México D.F. (Mexico); Reynoso-Mejía, Alberto [Unidad de Imagen Molecular PET/CT, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, Insurgentes Sur 3877 Col. La Fama, 14269, México D.F., Mexico and Departamento de Neuroimagen, Instituto Nacional de (Mexico); Casares-Cruz, Katiuzka; Taboada-Barajas, Jesús [Departamento de Neuroimagen, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez, Insurgentes Sur 3877 Col. La Fama, 14269, México D.F. (Mexico)

    2014-11-07

    In the radiology department of the Mexican National Institute of Neurology and Neurosurgery, a dedicated institute in Mexico City, on average 19.3 computed tomography (CT) examinations are performed daily on hospitalized patients for neurological disease diagnosis, control scans and follow-up imaging. The purpose of this work was to estimate the effective dose received by hospitalized patients who underwent a diagnostic CT scan using typical effective dose values for all CT types and to obtain the estimated effective dose distributions received by surgical and non-surgical patients. Effective patient doses were estimated from values per study type reported in the applications guide provided by the scanner manufacturer. This retrospective study included all hospitalized patients who underwent a diagnostic CT scan between 1 January 2011 and 31 December 2012. A total of 8777 CT scans were performed in this two-year period. Simple brain scan was the CT type performed the most (74.3%) followed by contrasted brain scan (6.1%) and head angiotomography (5.7%). The average number of CT scans per patient was 2.83; the average effective dose per patient was 7.9 mSv; the mean estimated radiation dose was significantly higher for surgical (9.1 mSv) than non-surgical patients (6.0 mSv). Three percent of the patients had 10 or more brain CT scans and exceeded the organ radiation dose threshold set by the International Commission on Radiological Protection for deterministic effects of the eye-lens. Although radiation patient doses from CT scans were in general relatively low, 187 patients received a high effective dose (>20 mSv) and 3% might develop cataract from cumulative doses to the eye lens.

  10. Patient dose estimation from CT scans at the Mexican National Neurology and Neurosurgery Institute

    Science.gov (United States)

    Alva-Sánchez, Héctor; Reynoso-Mejía, Alberto; Casares-Cruz, Katiuzka; Taboada-Barajas, Jesús

    2014-11-01

    In the radiology department of the Mexican National Institute of Neurology and Neurosurgery, a dedicated institute in Mexico City, on average 19.3 computed tomography (CT) examinations are performed daily on hospitalized patients for neurological disease diagnosis, control scans and follow-up imaging. The purpose of this work was to estimate the effective dose received by hospitalized patients who underwent a diagnostic CT scan using typical effective dose values for all CT types and to obtain the estimated effective dose distributions received by surgical and non-surgical patients. Effective patient doses were estimated from values per study type reported in the applications guide provided by the scanner manufacturer. This retrospective study included all hospitalized patients who underwent a diagnostic CT scan between 1 January 2011 and 31 December 2012. A total of 8777 CT scans were performed in this two-year period. Simple brain scan was the CT type performed the most (74.3%) followed by contrasted brain scan (6.1%) and head angiotomography (5.7%). The average number of CT scans per patient was 2.83; the average effective dose per patient was 7.9 mSv; the mean estimated radiation dose was significantly higher for surgical (9.1 mSv) than non-surgical patients (6.0 mSv). Three percent of the patients had 10 or more brain CT scans and exceeded the organ radiation dose threshold set by the International Commission on Radiological Protection for deterministic effects of the eye-lens. Although radiation patient doses from CT scans were in general relatively low, 187 patients received a high effective dose (>20 mSv) and 3% might develop cataract from cumulative doses to the eye lens.

  11. CT scan assessment in salivary gland lithiasis diagnosis.

    Science.gov (United States)

    Gardon, M A; Foletti, J M; Avignon, S; Graillon, N; Chossegros, C

    2017-11-22

    The aim of the study was to assess computed tomography (CT) scan efficiency for the diagnosis of salivary lithiasis. Patients who were included were all the patients who consulted in our department for main salivary gland (submandibular and parotid) obstruction symptoms between June 2014 and December 2016. A CT scan without injection was prescribed for all of them. The 163 patients were divided into two groups after the CT scan: patients with and without lithiasis. During surgery, we confirmed the presence or absence of the lithiasis previously diagnosed on the CT scan. The patients were divided in two groups: case and control groups. For statistical analysis, the sensitivity, specificity, and the negative and positive predictive values of the preoperative CT scan were calculated. A total of 163 patients with a salivary obstructive syndrome were included. On the CT scans, we found lithiases (hyperdense images) in 157 glands ("CT scan⊕" group), and we found no lithiasis in 6 glands ("CT scan" group). In the "CT scan⊕" group, 203 lithiases were present. During surgery, we found and removed lithiases in 155 patients (case group), and 8 patients had no lithiases (control group). The overall sensitivity, specificity, positive predictive value, and negative predictive values of the CT scan for the detection of lithiasis were 100%, 75%, 99%, and 100%, respectively. The specificity of CT scans for the lithiasis located in the anterior and middle third of the duct was 100%. According to our study, the CT scan is very efficient in diagnosing salivary main gland lithiases in patients with an obstructive syndrome. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  12. Evaluation of one year brain Computed Tomography scans at the ...

    African Journals Online (AJOL)

    Background: Advancement in technology has contributed immensely to medical practice. Computed tomography (CT), a yield of advanced technology has revolutionized the practice of neuroscience. Aim: To evaluate the first one year of brain computed tomography scan in the permanent site of University of Port Harcourt ...

  13. Clinical and CT scan pictures of cerebral cysticercosis

    Energy Technology Data Exchange (ETDEWEB)

    Singounas, E.G.; Krassanakis, K.; Karvounis, P.C. (Evangelismos Hospital, Athens (Greece))

    1982-01-01

    The clinical presentations and CT scan pictures of four patients harbouring big cysticercus cysts are described. The value of CT scanning in detecting these cysts is emphasized, and also the fact that these cysts can behave as space-occyping lesions, which must be differentiated from other cystic formations.

  14. Serial CT scans of cerebral hypoxia due to prolonged status epilepticus

    Energy Technology Data Exchange (ETDEWEB)

    Saiwai, Shigeo; Matsumura, Yasumasa; Tamaoka, Koichi; Fukuda, Teruo; Miyamoto, Takeshi (Kobe Central Municipal Hospital, Kobe (Japan))

    1983-04-01

    Serial computed tomography (CT) scans of 5 infants with status epilepticus were reviewed. Four out of the 5 infants fortunately had CT scans before status epilepticus because of a convulsion. There was a diffuse and mild low density in the hemisphere, with small ventricles and tight sulci (brain swelling) at 1 to 2 days after ictus. Thereafter, a diffuse low density became apparent except for the cerebellum, the brain stem, the thalamus, and the basal ganglia. Two to 4 weeks after ictus, a localized, mottled low density was demonstrated on the cerebral mantle and atrophic changes became progressively clear. In 3 cases, no abnormal enhancement was elicited on contrast CT scans performed between 5 to 16 days after status epilepticus. We discussed the possible pathophysiological aspects of the brain damage due to ''prolonged status epilepticus.''

  15. CT scan utilization patterns in pediatric patients with recurrent headache.

    Science.gov (United States)

    DeVries, Andrea; Young, Paul C; Wall, Eric; Getchius, Thomas ScD; Li, Chia-hsuan; Whitney, John; Rosenberg, Alan

    2013-07-01

    Although unnecessary for children with headache and normal history, computed tomography (CT) scans are widely used. This study sought to determine current practice patterns of neuroimaging to diagnose pediatric headache in a variety of treatment settings and to identify factors associated with increased use of neuroimaging. This retrospective claims analysis included children (aged 3–17 years) with ≥2 medical claims for headache. The primary outcome was CT scan utilization on or after first presentation with headache in a physician’s office or emergency department (ED). Of 15 836 patients, 26% (4034 patients; mean age: 11.8 years) had ≥1 CT scan, 74% within 1 month of index diagnosis. Patients with ED visits were 4 times more likely to undergo a CT scan versus those without ED visits (P 20% received a CT scan during the study period. Evaluation by a neurologist was strongly associated with a lower likelihood of CT scan compared with other provider specialties (odds ratio: 0.37; P pediatric headache remains high despite existing guidelines, low diagnostic yield, and high potential risk. Implementing quality improvement initiatives to ensure that CT scans in children are performed only when truly indicated will reduce unnecessary exposure to ionizing radiation and associated cancer risks.

  16. CT-guided laser probe for ablation of brain tumors

    Directory of Open Access Journals (Sweden)

    Abdolhadi Daneshi

    2010-01-01

    Full Text Available   Abstract  In this study, 22 patients (15-75 years old were selected and transferred to CT scan for tumor ablation. For ablations, after prep and drep under the local anesthesia and mild sedation in proper position, small incision made and special needle inserted and guided by proper direction to the core of the tumor. Then, laser probe inserted through the needle and laser energy delivered. Although we have not a good prognosis in metastatic tumors but post-operative follow up and brain CT scan established the effect of laser on resection and evaporation and diminution of mass effect in tumor lesions.

  17. CT diagnosis of non-traumatic subarachnoid haemorrhage in patients with brain edema

    Energy Technology Data Exchange (ETDEWEB)

    Avrahami, E.; Katz, R.; Rabin, A.; Friedman, V. [Department of Diagnostic Radiology, E. Wolfson Medical Center 58100 Holon (Israel)

    1998-10-01

    The aim of the study is to prove, retrospectively, that it is unlikely that the computerized tomography (CT) diagnosis of subarachnoid haemorrhage (SH) accompanies the CT diagnosis of generalized brain edema. A total of 100 comatose patients underwent CT of the brain. Of this number, 42 underwent an enhanced CT scan. In 26 patients, lumbar puncture was also performed. A control group of ten patients diagnosed with headache and having a normal CT scan underwent NECT and ECT. Measurements of the white and gray matter density in Hounsfield units (HU) were performed in all 110 cases, including the controls. The brain tissue density and the difference between the densities of the white and gray matter were lower in the cases with brain edema than in the controls. The data values were statistically significant. Small cerebral ventricles, sulci and cisterns and small differences between white and gray matter measurements were observed in the CT scans of the brain edema cases. All 100 patients had CT diagnosis of brain edema and SH. There was no bloody or xanthochromic CSF in any of the 26 lumbar punctures performed. In the enhanced CT scans, there was poor or no filling of the lateral sinuses. The compression of the lateral sinuses by the edematous brain tissue most probably results in their stenosis or obstruction due to disturbed brain venous drainage which can mimic CT findings of SH. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  18. Preoperative CT scanning of 70 cases of rheumatic valvular disease

    Energy Technology Data Exchange (ETDEWEB)

    Take, Akira; Matuzaki, Shigeru; Oki, Shinichi (Jichi Medical School, Minamikawachi, Tochigi (Japan)) (and others)

    1992-05-01

    Seventy patients with rheumatic valvular disease were evaluated with preoperative CT scanning. The correlation of the obtained CT images to the operative findings were examined. Left atrial thrombi were found in 24 cases at the operation. CT scan had detected thrombi in 19 cases (79.2%) and echocardiography in 15 (62.5%). CT failed to find them in 5 cases in which the left atrial thrombi were less than 3 g. Echocardiogram, however, failed to detect thrombi in 9 cases, the largest being 14 g. There were 15 cases with left atrial calcification, in which 10 cases had left atrial thrombi. Nine cases out of these 10 cases had rough left atrial surface after thrombectomy. Early postoperative CT of 10 with left atrial calcification showed recurrent left atrial thrombi in 4 (40%) cases. Mitral valve calcification was found in 42 cases during operation. CT scan was able to detect it in 40 (95.2%), while echocardiogram detected in 34 cases (81.0%) (p<0.05). All mitral valves with calcification required replacement. Out of 30 cases with non calcified mitral valves, 9 underwent OMC, and the other 21 underwent mitral valve replacement. Aortic valve calcification was found in 9 out of 11 cases of aortic stenosis. All has been diagnosed by CT scan. In conclusion, 1. in detecting the left atrial thrombi, CT scan was superior to echo-cardiography, and provided useful information for planning the operative procedure including atrial approach and valvular manipulation, 2. CT scan could detect calcification of left atrial wall which had high incidence of thrombus formation and rough left atrial surface, 3. CT scan could detect calcification of both mitral and aortic valve, and showed the severity of valvular structural changes. (author).

  19. CT scan findings in cerebral paragonimiasis

    Energy Technology Data Exchange (ETDEWEB)

    Udaka, Fukashi; Okuda, Bungo; Okada, Masako; Okae, Shunji; Kameyama, Masakuni (Chikamori Hospital, Kochi (Japan))

    1982-12-01

    Computed tomography was performed on 5 patients with chronic cerebral paragonimiasis. CT showed solitary or multiple, amorphous, round, or oval calcifications, and ventricular enlargement in all 5 cases. A large low-density area is also found in 4 of the 5 cases. These CT findings are compatible with previously reported findings of simple X-ray films of the skull, pneumoencephalography, and pathological studies.

  20. Metal artifact reduction of CT scans to improve PET/CT

    NARCIS (Netherlands)

    Van Der Vos, Charlotte S.; Arens, Anne I.J.; Hamill, James J.; Hofmann, Christian; Panin, Vladimir Y.; Meeuwis, Antoi P.W.; Visser, Eric P.; De Geus-Oei, Lioe Fee

    2017-01-01

    In recent years, different metal artifact reduction methods have been developed for CT. These methods have only recently been introduced for PET/CT even though they could be beneficial for interpretation, segmentation, and quantification of the PET/CT images. In this study, phantom and patient scans

  1. Innovative advanced occlusion planning with superimposed CT and optical scans.

    Science.gov (United States)

    Tremblay, Gilbert

    2011-04-01

    In order to increase the likelihood of a successful treatment plan outcome, it is critical to be able to effectively view the patient's underlying bony skeletal relationship of his or her TMJ. An innovative approach suggested to achieve this is to use the CT scan, optical scan, and Kois deprogrammer. Once the vertical dimension has been increased, the novelty of this approach is the ability to superimpose both scans along with the Kois deprogrammer and, using computer software, evaluate the TMJ position in three dimensions. This case presentation describes how TMJ CT scan evaluation is used in planning a complex rehabilitation case, given that the occlusion structures can be visualized independently and interactively.

  2. [Direct total body CT scan in multi-trauma patients

    NARCIS (Netherlands)

    Sierink, J.C.; Saltzherr, T.P.; Edwards, M.J.R.; Beuker, B.J.; Patka, P.; Goslings, J.C.; studiegroep, R.

    2012-01-01

    BACKGROUND: Immediate total body computed tomography (CT) scanning has become important in the early diagnostic phase of trauma care because of its high diagnostic accuracy. However, literature provides limited evidence whether immediate total body CT leads to better clinical outcome then

  3. Clinical evaluation of chest x-rays, gallium-67 scans and CT scans in sarcoidosis

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, S.; Maeda, T. (Kochi Medical School (Japan)); Itoh, K.; Yamamoto, Y.; Machida, K.

    1981-10-01

    A comparative study of the accuracy of chest X-rays, Gallium-67 scans and CT scans for mediastinal lymphadenopathy of pulmonary sarcoidosis was performed. The ability of each examination to detect the lymphadenopathy of following 5 lymph node groups was evaluated, such as paratracheal, aorto-pulmonic window, subcarinal and both hilar lymph nodes. The results on 5 patients indicated that in the detection of right paratracheal and subcarinal lymphadenopathy, Gallium scans and CT scans were more sensitive than chest x-rays. Chest x-rays and Gallium scans were superior than CT in detecting bilateral hilar lymphadenopathy. In the involvement of aorto-pulmonic window nodes, Gallium scans and chest x-rays were more informative than CT. Combination of these three examination is effective in the detection of the above described lymphadenopathy.

  4. Anterior ethmoidal artery evaluation on coronal CT scans.

    Science.gov (United States)

    Souza, Soraia Ale; Souza, Marcia Maria Ale de; Gregório, Luís Carlos; Ajzen, Sergio

    2009-01-01

    The anterior ethmoidal artery (AEA) is an important point for frontal and ethmoid sinuses surgery. CT scans can identify landmarks to help the surgeon find the AEA. To identify the landmarks of the AEA on the orbital medial wall and on the lateral wall of the olfactory fossa. and to correlate the presence of supraorbital ethmoidal cells with spotting the anterior ethmoidal artery canal. Retrospective review of 198 direct coronal paranasal sinuses computed tomography (CT) scans from August to December, 2006. Supraorbital pneumatization was seen in 35% (70 scans). The AEA canal was seen in 41% (81 scans). The anterior ethmoidal sulcus was seen in 98% (194 scans) and the anterior ethmoidal foramen was seen in all the scans (100%). The anterior ethmoidal foramen and the anterior ethmoidal sulcus were anatomical landmarks present in almost 100% of the scans studied. There was a correlation between the presence of supraorbital pneumatization and AEA canal visualization.

  5. Potential cancer risk associated to CT scan. State of the art of epidemiological studies

    Energy Technology Data Exchange (ETDEWEB)

    Bernier, Marie-Odile; Baysson, Neige Joumy Helene; Jacob, Sophie; Laurier, Dominique [Institute for Radiological Protection and Nuclear Safety (IRSN), Fontenay-aux-Roses (France). Lab. of Epidemiology

    2013-07-01

    Introduction: The increasing use of computed tomography (CT) scans in paediatric population raises the question of a possible health impact of ionizing radiation exposure associated with CT scans. Material and methods: Two large cohort studies have been recently published that assessed the risk of cancer related to CT examinations of children and young adults. Methodology and results of these studies are presented. Results: The UK cohort included over 176,000 young people, who underwent one or more CT scans between 1985 and 2002. The Australian study compared the risk of cancer and leukaemia in a population of 680,000 young people exposed to CT scans between 1985 and 2005 to non-exposed similar age people. Both studies showed a significant dose-response relation between exposure to CT and leukaemia or brain tumour risks. These results are consistent with predictions from A-bomb survivors' data. However, uncertainties in dosimetric estimation and potential bias linked to underlying medical conditions should be considered. Conclusion and perspectives: Further studies with more accurate dosimetry and assessment of potential bias and uncertainties are needed. Ongoing national studies and the European collaborative EPI-CT study will help to better understand the relation between low level radiation exposure and cancer and to support recommendations for patients'' radiation protection. (orig.)

  6. Hybrid detection of lung nodules on CT scan images

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Lin; Tan, Yongqiang; Schwartz, Lawrence H.; Zhao, Binsheng, E-mail: bz2166@columbia.edu [Department of Radiology, Columbia University Medical Center, 630 West 168th Street, New York, New York 10032 (United States)

    2015-09-15

    Purpose: The diversity of lung nodules poses difficulty for the current computer-aided diagnostic (CAD) schemes for lung nodule detection on computed tomography (CT) scan images, especially in large-scale CT screening studies. We proposed a novel CAD scheme based on a hybrid method to address the challenges of detection in diverse lung nodules. Methods: The hybrid method proposed in this paper integrates several existing and widely used algorithms in the field of nodule detection, including morphological operation, dot-enhancement based on Hessian matrix, fuzzy connectedness segmentation, local density maximum algorithm, geodesic distance map, and regression tree classification. All of the adopted algorithms were organized into tree structures with multi-nodes. Each node in the tree structure aimed to deal with one type of lung nodule. Results: The method has been evaluated on 294 CT scans from the Lung Image Database Consortium (LIDC) dataset. The CT scans were randomly divided into two independent subsets: a training set (196 scans) and a test set (98 scans). In total, the 294 CT scans contained 631 lung nodules, which were annotated by at least two radiologists participating in the LIDC project. The sensitivity and false positive per scan for the training set were 87% and 2.61%. The sensitivity and false positive per scan for the testing set were 85.2% and 3.13%. Conclusions: The proposed hybrid method yielded high performance on the evaluation dataset and exhibits advantages over existing CAD schemes. We believe that the present method would be useful for a wide variety of CT imaging protocols used in both routine diagnosis and screening studies.

  7. Application of stereological estimates in patients with severe head injuries using CT and MR scanning images

    DEFF Research Database (Denmark)

    Eriksen, Nanna; Rostrup, E; Andersen, K

    2010-01-01

    applied stereological techniques to representative CT and MRI brain scans from five patients to describe how stereological methods, when applied to scans of trauma patients, can provide a useful supplement to the estimation of structural brain changes in head injuries. The reliability of the estimates...... traditional imaging methods are not always applicable and automatic methods may not be able to match the individual observer. Stereological techniques are alternative tools in the quantitative description of biological structures, and have been increasingly applied to the human brain. In the present study, we......Severe brain damage is often followed by serious complications. Quantitative measurements, such as regional volume and surface area under various conditions, are essential for understanding functional changes in the brain and assessing prognosis. The affected brain tissue is variable, hence...

  8. Segmentation of Brain Lesions in MRI and CT Scan Images: A Hybrid Approach Using k-Means Clustering and Image Morphology

    Science.gov (United States)

    Agrawal, Ritu; Sharma, Manisha; Singh, Bikesh Kumar

    2018-01-01

    Manual segmentation and analysis of lesions in medical images is time consuming and subjected to human errors. Automated segmentation has thus gained significant attention in recent years. This article presents a hybrid approach for brain lesion segmentation in different imaging modalities by combining median filter, k means clustering, Sobel edge detection and morphological operations. Median filter is an essential pre-processing step and is used to remove impulsive noise from the acquired brain images followed by k-means segmentation, Sobel edge detection and morphological processing. The performance of proposed automated system is tested on standard datasets using performance measures such as segmentation accuracy and execution time. The proposed method achieves a high accuracy of 94% when compared with manual delineation performed by an expert radiologist. Furthermore, the statistical significance test between lesion segmented using automated approach and that by expert delineation using ANOVA and correlation coefficient achieved high significance values of 0.986 and 1 respectively. The experimental results obtained are discussed in lieu of some recently reported studies.

  9. CT Scanning Imaging Method Based on a Spherical Trajectory.

    Directory of Open Access Journals (Sweden)

    Ping Chen

    Full Text Available In industrial computed tomography (CT, the mismatch between the X-ray energy and the effective thickness makes it difficult to ensure the integrity of projection data using the traditional scanning model, because of the limitations of the object's complex structure. So, we have developed a CT imaging method that is based on a spherical trajectory. Considering an unrestrained trajectory for iterative reconstruction, an iterative algorithm can be used to realise the CT reconstruction of a spherical trajectory for complete projection data only. Also, an inclined circle trajectory is used as an example of a spherical trajectory to illustrate the accuracy and feasibility of this new scanning method. The simulation results indicate that the new method produces superior results for a larger cone-beam angle, a limited angle and tabular objects compared with traditional circle trajectory scanning.

  10. CT-scanning of ancient Greenlandic Inuit temporal bones

    Energy Technology Data Exchange (ETDEWEB)

    Homoe, P. (Copenhagen Univ. (Denmark). Lab. of Biological Anthropology and Dept. of Otolaryngology, Head and Neck Surgery); Lynnerup, N. (Copenhagen Univ., Lab. of Biological Anthropology and Univ. Inst. of Ferensic Medicine, Copenhagen (Denmark)); Videbaek, H. (Hvidovre Univ. Hospital, Copenhagen (Denmark). Dept. of Radiology)

    1992-01-01

    Additional morphological evidence of former infectious middle ear disease (IMED) was found by CT-scanning in 5 of 6 Greenlandic Inuit crania strongly suspected for former IMED due to earlier examination revealing either bilateral hypocellularity or asymmetry of the pneumatized area of the temporal bones. The CT-scans showed sclerosing and obliteration of the air cells and even destruction of the cellular septae, and a high degree of irregularity of the cells. Sclerosing of the surrounding bone tissue was also found. The findings in one cranium were dubious and could both be regarded as a congenital malformation or an infection in infanthood. CT-scan confirms and even adds to the results of conventional X-ray of temporal bones making hypotheses of paleopathology more reliable. The findings also support the environmental theory of pneumatization of the air cell system in the temporal bones. (13 refs., 10 figs.).

  11. Introduction of the Canadian CT Head Rule Reduces CT Scan Use ...

    African Journals Online (AJOL)

    Minor head injuries accounts for majority of non-fatal head injury and is associated with significant resource use. The utility of the CT scan in cases of mild head injury is undetermined although a big proportion of our patients are offered the investigation. We hypothesized that the introduction of the Canadian CT head rule ...

  12. MRI of patients with cerebral palsy and normal CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Bogaert, P. van; Szliwowski, H.B. (Hopital Erasme, Brussels (Belgium). Dept. of Neurology); Baleriaux, D.; Christophe, C. (Hopital Erasme, Brussels (Belgium). Dept. of Radiology (Neuroradiology))

    1992-02-01

    Three children with clinical evidence of cerebral palsy (CP) and normal cerebral computed tomography (CT) scans were evaluated by magnetic resonance imaging (MRI) to identify CT-undetectable white matter lesions in the watershed zones of arterial territories. The two patients with spastic diplegia showed bilateral lesions either in the subcortical regions or in the occipital periventricular regions. The patient with congenital hemiplegia exhibited unilateral lesions in the periventricular region. We conclude that MRI is more informative than CT for the evaluation of patients with CP. (orig.).

  13. Analysis of cranial CT-scan findings in cerebral palsy

    Energy Technology Data Exchange (ETDEWEB)

    Wada, F.; Andoh, T.; Une, K.; Takamatsu, T. (Kitakyushu Municipal Sogo-Ryoiku Center (Japan))

    1981-06-01

    CT-scan findings of 87 cerebral palsied children were studied. They consist of 23 cases of spastic quadriplegia, 9 cases of diplegia, 12 cases of paraplegia, 24 cases of athetosis and mixed type, and 19 cases of hemiplegia. In the former four types, ventricular dilatation and cortical atrophy were measured and abnormal changes in cerebral substance and cerebellar atrophy were observed. Spastic quadriplegia showed most intense changes in every aspect of the abnormalities, while paraplegia had almost normal appearance. Athetosis and mixed type had moderate changes. Hemiplegia always showed asymmetrical view on CT-scan, dilatation of lateral ventricle or atrophy of hemisphere in contralateral side being observed.

  14. CT-scanning of ancient Greenlandic Inuit temporal bones

    DEFF Research Database (Denmark)

    Homøe, P; Lynnerup, N; Videbaek, H

    1992-01-01

    Additional morphological evidence of former infectious middle ear disease (IMED) was found by CT-scanning in 5 of 6 Greenlandic Inuit crania strongly suspected for former IMED due to earlier examination revealing either bilateral hypocellularity or asymmetry of the pneumatized area of the temporal...... as a congenital malformation or an infection in infanthood. CT-scan confirms and even adds to the results of conventional X-ray of temporal bones making hypotheses of paleopathology more reliable. The findings also support the environmental theory of pneumatization of the air cell system in the temporal bones....

  15. Metal Artifact Reduction of CT Scans to Improve PET/CT.

    Science.gov (United States)

    van der Vos, Charlotte S; Arens, Anne I J; Hamill, James J; Hofmann, Christian; Panin, Vladimir Y; Meeuwis, Antoi P W; Visser, Eric P; de Geus-Oei, Lioe-Fee

    2017-11-01

    In recent years, different metal artifact reduction methods have been developed for CT. These methods have only recently been introduced for PET/CT even though they could be beneficial for interpretation, segmentation, and quantification of the PET/CT images. In this study, phantom and patient scans were analyzed visually and quantitatively to measure the effect on PET images of iterative metal artifact reduction (iMAR) of CT data. Methods: The phantom consisted of 2 types of hip prostheses in a solution of (18)F-FDG and water. (18)F-FDG PET/CT scans of 14 patients with metal implants (either dental implants, hip prostheses, shoulder prostheses, or pedicle screws) and (68)Ga-labeled prostate-specific membrane antigen ((68)Ga-PSMA) PET/CT scans of 7 patients with hip prostheses were scored by 2 experienced nuclear medicine physicians to analyze clinical relevance. For all patients, a lesion was located in the field of view of the metal implant. Phantom and patients were scanned in a PET/CT scanner. The standard low-dose CT scans were processed with the iMAR algorithm. The PET data were reconstructed using attenuation correction provided by both standard CT and iMAR-processed CT. Results: For the phantom scans, cold artifacts were visible on the PET image. There was a 30% deficit in (18)F-FDG concentration, which was restored by iMAR processing, indicating that metal artifacts on CT images induce quantification errors in PET data. The iMAR algorithm was useful for most patients. When iMAR was used, the confidence in interpretation increased or stayed the same, with an average improvement of 28% ± 20% (scored on a scale of 0%-100% confidence). The SUV increase or decrease depended on the type of metal artifact. The mean difference in absolute values of SUVmean of the lesions was 3.5% ± 3.3%. Conclusion: The iMAR algorithm increases the confidence of the interpretation of the PET/CT scan and influences the SUV. The added value of iMAR depends on the indication for

  16. The usefulness of a computerized tomographic scan taken parallel to the clivus in the management of brain-stem lesions

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Akio; Mishima, Kazuhiko; Miyagawa, Naohisa; Aritake, Kouichi; Segawa, Hiromu; Sano, Keiji (Fuji Brain Instutue and Hospital, Shizuoka (Japan))

    1989-04-01

    It is important to detect the definite sites and extent of lesions in the management of brainstem infarction. While axial computerized tomographic scan (axial CT) has usually been used to map brain-stem lesions, it often fails to show small lesions or their longitudinal extent. In this report, the usefulness of CT scan using scan slices taken parallel to the clivus (clival CT) is evaluated in cases of brain-stem infarction. Clival CT was performed with the patient in a supine position, with as much neck flexion as possible. CT slices were taken parallel to the clivus (orbito-meatal line, 35-50 deg.). Both axial and clival CT scans were performed in 25 patients with brain-stem infarctions. Axial CT was most useful in detecting small lesions located in the ventral pons and in showing the anatomical structure which was involved. On the other hand, clival CT was superior in demonstrating the longitudinal extent of infarctions, especially in the midbrain or thalamus. In cases with major brain-stem infarctions or in cases with associated cerebellar lesions, the combination of axial and clival CT shows the configuration and continuity of the lesions clearly. Therefore, clival CT, when used with axial CT, clearly shows the three-dimensional extent of brain-stem infarctions; this technique is also recommended when managing other types of brain-stem disease. In addition, it is important to select appropriate CT slice angles in order to demonstrate the anatomical structure of interest. (author).

  17. The value of brain CT findings in acute methanol toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Taheri, Morteza Sanei [Department of Radiology, Shohada Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Poison Control Center, Loghman-Hakim Poison Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)], E-mail: saneim@yahoo.com; Moghaddam, Hossein Hassanian [Poison Control Center, Loghman-Hakim Poison Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Moharamzad, Yashar; Dadgari, Shahrzad [Department of Radiology, Shohada Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of); Nahvi, Vahideh [Poison Control Center, Loghman-Hakim Poison Hospital, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2010-02-15

    Objective: Due to depressant effects of methanol on the central nervous system, brain computed tomography (CT) scan has been introduced as a diagnostic device in methanol intoxication. The authors aimed to present brain CT findings in patients with acute methanol intoxication and to determine signs associated with death. Materials and methods: This cohort study involved 42 consecutive patients with acute methanol intoxication. Inclusion criteria were consisted of characteristic clinical presentation of methanol poisoning, and metabolic acidosis with increased anion and osmolar gaps. Brain CT scans without contrast medium were obtained. To determine the association between the CT findings and death, the chi-square test or the Fisher's exact test, odds ratio (OR) and its 95% confidence interval (95% CI) were calculated. Results: Twenty-eight patients (66.6%) had a total of 55 abnormal findings on brain CT, in which bilateral putaminal hypodense lesions was the most common manifestation (27 cases, 96.4%). Putaminal hemorrhage with varying degrees was observed in 7 patients (25%). Six patients (21.4%) had low attenuation lesions in the subcortical white matter of the insula. A significant association was observed between putaminal hemorrhage (OR = 8, 95% CI = 1.187-53.93, P = 0.018) and subcortical necrosis of the insula (OR = 11, 95% CI = 1.504-80.426, P = 0.007) with death. Conclusion: In addition to clinical and laboratory findings, presence of putaminal hemorrhage and insular subcortex white matter necrosis are associated with a poor clinical outcome in patients with methanol poisoning.

  18. Diagnostic Utility of CT Scan for Acute Headache

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2009-08-01

    Full Text Available ED records for 364 children 2 to 5 years of age who presented to the Children’s National Medical Center ED, Washington, DC, between July 1, 2003, and June 30, 2006, with headache as their chief complaint, were examined to determine whether CT scans led to better acute management, justifying the risk of radiation.

  19. Classication Methods for CT-Scanned Carcass Midsections

    DEFF Research Database (Denmark)

    Skytte, Jacob Lercke; Dahl, Anders Lindbjerg; Larsen, Rasmus

    2011-01-01

    in the segmentation of the outer fat layer in the mid- section of CT-scanned pig carcasses. Prior information about the carcass composition can potentially be applied for a fully automated solution, in order to optimize the slaughter line. The methods comprise Markov Random Field and contextual Bayesian classication...

  20. A simulation study on proton computed tomography (CT) stopping power accuracy using dual energy CT scans as benchmark

    DEFF Research Database (Denmark)

    Hansen, David Christoffer; Seco, Joao; Sørensen, Thomas Sangild

    2015-01-01

    development) have both been proposed as methods for obtaining patient stopping power maps. The purpose of this work was to assess the accuracy of proton CT using dual energy CT scans of phantoms to establish reference accuracy levels. Material and methods. A CT calibration phantom and an abdomen cross section...... phantom containing inserts were scanned with dual energy and single energy CT with a state-of-the-art dual energy CT scanner. Proton CT scans were simulated using Monte Carlo methods. The simulations followed the setup used in current prototype proton CT scanners and included realistic modeling...

  1. [MRI and CT-scan in presumed benign ovarian tumors].

    Science.gov (United States)

    Thomassin-Naggara, I; Bazot, M

    2013-12-01

    Radiological examinations are required for the assessment of complex or indeterminate ovarian masses, mainly using MRI and CT-scan. MRI provides better tissue characterization than Doppler ultrasound or CT-scan (LE2). Pelvic MRI is recommended in case of an indeterminate or complex ovarian ultrasonographic mass (grade B). The protocol of a pelvic MRI should include morphological T1 and T2 sequences (grade B). In case of solid portion, perfusion and diffusion sequences are recommended (grade C). In case of doubt about the diagnosis of ovarian origin, pelvic MRI is preferred over the CT-scan (grade C). MRI is the technique of choice for the difference between functional and organic ovarian lesion diagnosis (grade C). It can be useful in case of clinical diagnostic uncertainty between polycystic ovary syndrome and ovarian hyperstimulation and multilocular ovarian tumor syndrome (grade C). No MRI classification for ovarian masses is currently validated. The establishment of a presumption of risk of malignancy is required in a MRI report of adnexal mass with if possible a guidance on the histological diagnosis. In the absence of clinical or sonographic diagnosis, pelvic CT-scan is recommended in the context of acute painful pelvic mass in non-pregnant patients (grade C). It specifies the anomalies and allows the differential diagnosis with digestive and urinary diseases (LE4). Given the lack of data in the literature, the precautionary principle must be applied to the realization of a pelvic MRI in a pregnant patient. A risk-benefit balance should be evaluated case by case by the clinician and the radiologist and information should be given to the patient. In an emergency situation during pregnancy, pelvic MRI is an alternative to CT-scan for the exploration of acute pelvic pain in case of uncertain sonographic diagnosis (grade C). Copyright © 2013. Published by Elsevier Masson SAS.

  2. Automated delineation of stroke lesions using brain CT images

    Directory of Open Access Journals (Sweden)

    Céline R. Gillebert

    2014-01-01

    Full Text Available Computed tomographic (CT images are widely used for the identification of abnormal brain tissue following infarct and hemorrhage in stroke. Manual lesion delineation is currently the standard approach, but is both time-consuming and operator-dependent. To address these issues, we present a method that can automatically delineate infarct and hemorrhage in stroke CT images. The key elements of this method are the accurate normalization of CT images from stroke patients into template space and the subsequent voxelwise comparison with a group of control CT images for defining areas with hypo- or hyper-intense signals. Our validation, using simulated and actual lesions, shows that our approach is effective in reconstructing lesions resulting from both infarct and hemorrhage and yields lesion maps spatially consistent with those produced manually by expert operators. A limitation is that, relative to manual delineation, there is reduced sensitivity of the automated method in regions close to the ventricles and the brain contours. However, the automated method presents a number of benefits in terms of offering significant time savings and the elimination of the inter-operator differences inherent to manual tracing approaches. These factors are relevant for the creation of large-scale lesion databases for neuropsychological research. The automated delineation of stroke lesions from CT scans may also enable longitudinal studies to quantify changes in damaged tissue in an objective and reproducible manner.

  3. CT Scanning in Identification of Sheep Cystic Echinococcosis

    Directory of Open Access Journals (Sweden)

    Rui Mao

    2017-01-01

    Full Text Available Objective. We aim to determine the efficiency of CT in identification of cystic echinococcosis in sheep. Methods. Fifty-three sheep with liver cysts confirmed by ultrasonography were subject to CT scan to evaluate the number, size, and type of the cysts in liver and lung, confirmed using necropsy. The correlation of numbers between liver cysts and lung cysts was calculated using Pearson analysis. Results. Necropsy indicated a 98% consensus on size, location, number, and activity compared with CT scan. The viable cysts were 53.1% and 50.6% in the liver and lung, respectively. Among the cysts in liver, 35.5%, 9.5%, 5.7%, 10.2%, and 39.1% were Types CE1, CE2, CE3, CE4, and CE5, respectively. The cysts in the lungs, 17.4%, 26.9%, 12.1%, 11.6%, and 32.1%, were Types CE1, CE2, CE3, CE4, and CE5, respectively. A significant correlation was noticed between the number of cysts in liver and those in lung (R=0.770, P<0.001. Conclusions. CT scan is a suitable tool in determining the size and type of cystic hydatid cysts in both liver and lung of sheep. A significant correlation was noticed between the numbers in liver and lung, indicating that lung infection was likely due to the expansion of liver cyst burden pressure.

  4. Interactive annotation of textures in thoracic CT scans

    Science.gov (United States)

    Kockelkorn, Thessa T. J. P.; de Jong, Pim A.; Gietema, Hester A.; Grutters, Jan C.; Prokop, Mathias; van Ginneken, Bram

    2010-03-01

    This study describes a system for interactive annotation of thoracic CT scans. Lung volumes in these scans are segmented and subdivided into roughly spherical volumes of interest (VOIs) with homogeneous texture using a clustering procedure. For each 3D VOI, 72 features are calculated. The observer inspects the scan to determine which textures are present and annotates, with mouse clicks, several VOIs of each texture. Based on these annotations, a k-nearest-neighbor classifier is trained, which classifies all remaining VOIs in the scan. The algorithm then presents a slice with suggested annotations to the user, in which the user can correct mistakes. The classifier is retrained, taking into account these new annotations, and the user is presented another slice for correction. This process continues until at least 50% of all lung voxels in the scan have been classified. The remaining VOIs are classified automatically. In this way, the entire lung volume is annotated. The system has been applied to scans of patients with usual and non-specific interstitial pneumonia. The results of interactive annotation are compared to a setup in which the user annotates all predefined VOIs manually. The interactive system is 3.7 times as fast as complete manual annotation of VOIs and differences between the methods are similar to interobserver variability. This is a first step towards precise volumetric quantitation of texture patterns in thoracic CT in clinical research and in clinical practice.

  5. CT scan findings of patients with Rett syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Hisaharu; Takanashi, Aiko; Hirayama, Yoshito; Sakuragawa, Norio; Arima, Masataka; Tateno, Akihiko; Koide, Hiroyoshi.

    1989-05-01

    CT findings and clinical features were analyzed in 16 female patients with Rett syndrome, whose ages were between 4 and 20. Fifteen patients had microcrania. Twelve patients were able to stand and run; however, the remaining 4 patients had the only ability to sit. CT revealed an atrophy of the ponse and various degrees of dilatation in the Silvian fissure, frontal sulcus, and space between the cranium and the frontal polar lobe. An atrophy in the frontal lobe, cerebral cortex surrounding the Silvian fissure, and white matter directly below the cortex seemed to have an important role in the occurrence of this syndrome. There was, however, no definitive correlation between the degree of atrophy and both the patient's age and motor function. Serial CT scannings with clinical process are required. (Namekawa, K).

  6. Progression of CT scan findings in Rett syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Hisaharu; Hirayama, Yoshito; Sakuragawa, Norio; Arima, Masataka (National Center of Neurology and Psychiatry, Kodaira, Tokyo (Japan))

    1989-07-01

    Progression of the lesions revealed by CT scan was observed in five girls with Rett syndrome. The most distinct and common finding was progressive dilatation of Sylvian fissures, frontal extracerebral space, interhemispheric fissure, and sulci mainly in frontal lobe. It may indicate progressive lesion in the frontal and the temporal lobes. In addition, dilatation of the anterior horns of the lateral ventricles and the third ventricle was noted in some cases. Brainstem and cerebellum were small at any age with some morphological development as the patients became elder. Neither malformations nor abnormalities in density were found in any case. It is concluded that the main lesion of Rett syndrome on CT scan is progressive and localized in the frontal and the temporal lobes. (author).

  7. Brain Lesions

    Science.gov (United States)

    Symptoms Brain lesions By Mayo Clinic Staff A brain lesion is an abnormality seen on a brain-imaging test, such as ... tomography (CT). On CT or MRI scans, brain lesions appear as dark or light spots that don' ...

  8. CENTRAL ASSESSMENT OF COMPUTED TOMOGRAPHY BRAIN SCANS

    Directory of Open Access Journals (Sweden)

    Lesley Ann Cala

    2016-08-01

    Full Text Available Development of multislice CT (MSCT scanners since 1998 has resulted in submillimetre thick slices being able to be acquired, without increasing the radiation dose to the patient. Although the incident x-ray beam is widened in the slice thickness direction (Z-direction, the emergent x-rays fall upon multiple rows of small detectors. This means data can be collected simultaneously for more than one slice per rotation of the x-ray tube. For example, the dose received by the patient will be the same for four thin slices of 2.5 mm, as for one slice of 10 mm thickness. A 64-slice MSCT can create 0.625 mm thick slices. This leads to high diagnostic value in the detection of small abnormalities in stroke patients and in the reconstruction of data from CT angiography (CTA of the brain.

  9. CT scan of Parkinson's disease

    Energy Technology Data Exchange (ETDEWEB)

    Konishi, T.; Noguchi, S.; Nishitani, H. (National Sanatorium of Utano, Kyoto (Japan)); Kitano, H.; Ikegami, Y.

    1981-04-01

    In forty-eight patients with Parkinson's disease, we examined the ventricular size and the degree of cortical atrophy which were measured by the photos of CT scan and compared them with their clinical symptoms and side effects of anti-parkinsonian drugs. The ventricular size was expressed as the ventricular ratio which is the percentage of superimposed lateral ventricular area to the white and gray matter area at the slice number 2B of CT scan photos. The degree of the cortical atrophy was expressed as the sulcal numbers which were clearly visualized at the slice number 3B or 4A of CT scan photos. We used the CT scan photos of age-matched other patients which did not show definit central nervous system abnormalities. Our findings were as follows: (1) The ventricular enlargement was observed in the parkinsonian patients who showed dementia and/or Yahr's classification grades IV or V. (2) There was no correlation between the duration of this disease and the L--dopa treatments with the ventricular size and sulcal numbers. (3) The side effects of drugs such as visual hallucination were tended to be observed in the patients who showed the ventricular enlargement. (4) There was no definite correlation between the degree of cortical atrophy with clinical symptoms and side effects of various drugs. These findings suggested that the ventricular enlargement in Parkinson's disease was an important sign of dementia and the tendency of appearance of side effects of various drugs.

  10. CT scan of the spine for herniated discs

    Energy Technology Data Exchange (ETDEWEB)

    Gulati, A.N.; Weinstein, R.; Studdard, E.

    1981-10-01

    The high resolution conversion kit introduced for the EMI CT 5005 scanner has twice the spatial resolution of the usual scan mode and has proven to be quite useful in evaluation of the spinal canal. The present study was performed to determine the capability of the high resolution system to diagnose herniated lumbar disc without intrathecal contrast. HNP was diagnosed in 83% of the cases which had a positive myelogram, 70% of which had operation and all were proven positive.

  11. Subacute sclerosing panencephalitis. Changes on CT scan during acute relapse

    Energy Technology Data Exchange (ETDEWEB)

    Modi, G.; Bill, P. (Wentworth Hospital, Durban (South Africa). Dept. of Medicine); Campbell, H. (Wentworth Hospital, Durban (South Africa). Dept. of Radiology)

    1989-11-01

    A 19-year-old female patient presented in an acute state of akinetic mutism. Serological analysis of serum and cerebrospinal fluid demonstrated the presence of antibodies to measles virus. CT scan carried out during this acute phase of relapse demonstrated white matter enhancement affecting the cortical white matter of the frontal lobes and corpus callosum. These features indicate that active demyelination occurs during acute relapse in subacute sclerosing panencephalitis (SSPE) and suggest that immunotherapy should be considered during this acute phase. (orig.).

  12. Analysis of functional CT scan in cervical vertebral disease

    Energy Technology Data Exchange (ETDEWEB)

    Hirofuji, Eiichi; Tanaka, Seisuke; Tomihara, Mitsuo; Kita, Hiroshi; Yamasaki, Hiroyuki

    1982-12-01

    The atlantoaxial joint showed displacement in various directions in rheumatoid arthritis and cervical spondylosis. The displacements were promoted by anterior flexion and rotatory movements, exerting great influences on the spnial cord. The intervertebral space between the 5th and 6th vertebra showed narrowing of the vertebral canal in cervical spondylosis and was promoted by posterior flexion to affect the spinal cord to a great extent. Functional CT scan was useful for observation of pathologic conditions of vertebral diseases.

  13. Colitis detection on abdominal CT scans by rich feature hierarchies

    Science.gov (United States)

    Liu, Jiamin; Lay, Nathan; Wei, Zhuoshi; Lu, Le; Kim, Lauren; Turkbey, Evrim; Summers, Ronald M.

    2016-03-01

    Colitis is inflammation of the colon due to neutropenia, inflammatory bowel disease (such as Crohn disease), infection and immune compromise. Colitis is often associated with thickening of the colon wall. The wall of a colon afflicted with colitis is much thicker than normal. For example, the mean wall thickness in Crohn disease is 11-13 mm compared to the wall of the normal colon that should measure less than 3 mm. Colitis can be debilitating or life threatening, and early detection is essential to initiate proper treatment. In this work, we apply high-capacity convolutional neural networks (CNNs) to bottom-up region proposals to detect potential colitis on CT scans. Our method first generates around 3000 category-independent region proposals for each slice of the input CT scan using selective search. Then, a fixed-length feature vector is extracted from each region proposal using a CNN. Finally, each region proposal is classified and assigned a confidence score with linear SVMs. We applied the detection method to 260 images from 26 CT scans of patients with colitis for evaluation. The detection system can achieve 0.85 sensitivity at 1 false positive per image.

  14. Dose profile study in head CT scans using radiochromic films

    Energy Technology Data Exchange (ETDEWEB)

    Ladino G, A. M.; Prata M, A., E-mail: amlgphys@gmail.com [Universidade Federal de Minas Gerais, Departamento de Engenharia Nuclear, Av. Pte. Antonio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais (Brazil)

    2016-10-15

    Diagnostic images of computed tomography generate higher doses than other methods of diagnostic radiology using X-ray beam attenuation. Clinical applications of CT have been increased by technological advances, what leads to a wide variety of scanner in the Brazilian technological pool. It has been difficult to implement dose reduction strategies because of the lack of proper guidance on computed tomography examinations. However, CT scanners allow adjusting acquisition parameter according to the patients physical profile and diagnostic application for which the scan is intended. The knowledge of the dose distribution is important because changes in image acquisition parameters may provide dose reduction. In this study, it was used a cylindrical head phantom in PMMA with 5 openings, what allows dose measurement in 5 regions. In a GE CT scanner, Discovery model of 64 channels, the central slice of the head phantom was irradiated and the absorbed doses were measured using a pencil ionization chamber. Radiochromic film strips were placed in the peripheral and in the central region of the head phantom and was performed a scan of 10 cm in the phantom central region. The scan was performed using the head scanning protocol of the radiobiology service, with a voltage of 120 kV. After scanning, the radiochromic film strips were digitalized and their digital images were used to have the dose longitudinal profiles. The dose values recorded have variation in a range of 18.66 to 23.57 mGy. In the results it was compared the dose index values obtained by the pencil chamber measurement to the dose longitudinal profiles recorded by the film strips. (Author)

  15. Variation of quantitative emphysema measurements from CT scans

    Science.gov (United States)

    Keller, Brad M.; Reeves, Anthony P.; Henschke, Claudia I.; Barr, R. Graham; Yankelevitz, David F.

    2008-03-01

    Emphysema is a lung disease characterized by destruction of the alveolar air sacs and is associated with long-term respiratory dysfunction. CT scans allow for imaging of the anatomical basis of emphysema, and several measures have been introduced for the quantification of the extent of disease. In this paper we compare these measures for repeatability over time. The measures of interest in this study are emphysema index, mean lung density, histogram percentile, and the fractal dimension. To allow for direct comparisons, the measures were normalized to a 0-100 scale. These measures have been computed for a set of 2,027 scan pairs in which the mean interval between scans was 1.15 years (σ: 93 days). These independent pairs were considered with respect to three different scanning conditions (a) 223 pairs where both were scanned with a 5 mm slice thickness protocol, (b) 695 with the first scanned with the 5 mm protocol and the second with a 1.25 mm protocol, and (c) 1109 pairs scanned both times using a 1.25 mm protocol. We found that average normalized emphysema index and histogram percentiles scores increased by 5.9 and 11 points respectively, while the fractal dimension showed stability with a mean difference of 1.2. We also found, a 7 point bias introduced for emphysema index under condition (b), and that the fractal dimension measure is least affected by scanner parameter changes.

  16. Whole-brain dynamic CT angiography and perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Orrison, W.W. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Department of Medical Education, University of Nevada School of Medicine, Reno, NV (United States); Snyder, K.V.; Hopkins, L.N. [Department of Neurosurgery, Millard Fillmore Gates Circle Hospital, Buffalo, NY (United States); Roach, C.J. [School of Life Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Ringdahl, E.N. [Department of Psychology, University of Nevada Las Vegas, Las Vegas, NV (United States); Nazir, R. [Shifa International Hospital, Islamabad (Pakistan); Hanson, E.H., E-mail: eric.hanson@amigenics.co [College of Osteopathic Medicine, Touro University Nevada, Henderson, NV (United States); Department of Health Physics and Diagnostic Sciences, University of Nevada Las Vegas, Las Vegas, NV (United States); Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States)

    2011-06-15

    The availability of whole brain computed tomography (CT) perfusion has expanded the opportunities for analysing the haemodynamic parameters associated with varied neurological conditions. Examples demonstrating the clinical utility of whole-brain CT perfusion imaging in selected acute and chronic ischaemic arterial neurovascular conditions are presented. Whole-brain CT perfusion enables the detection and focused haemodynamic analyses of acute and chronic arterial conditions in the central nervous system without the limitation of partial anatomical coverage of the brain.

  17. Interobserver variability in visual evaluation of thoracic CT scans and comparison with automatic computer measurements of CT lung density

    DEFF Research Database (Denmark)

    Winkler Wille, Mathilde Marie; Thomsen, Laura Hohwü; Dirksen, Asger

    2012-01-01

    lung density measurements, i.e. densitometry. Methods – In a pilot study 60 CT scans were selected from a sample of 3980 CT scans from The Danish Lung Cancer Screening Trial (DLCST). The amount of emphysema in these scans was scored independently by two observers, who were blinded regarding clinical...

  18. Introduction of the Canadian CT Head Rule Reduces CT Scan Use ...

    African Journals Online (AJOL)

    use. The utility of the CT scan in cases of mild head injury is undetermined although a big proportion of our patients are offered the investigation. We hypothesized that the ... observation or discharged as appropriate to the rule. Results: The ... GCS score less than 15 at 2h after injury or do not improve to a GCS level of 15 ...

  19. CT scan range estimation using multiple body parts detection: let PACS learn the CT image content.

    Science.gov (United States)

    Wang, Chunliang; Lundström, Claes

    2016-02-01

    The aim of this study was to develop an efficient CT scan range estimation method that is based on the analysis of image data itself instead of metadata analysis. This makes it possible to quantitatively compare the scan range of two studies. In our study, 3D stacks are first projected to 2D coronal images via a ray casting-like process. Trained 2D body part classifiers are then used to recognize different body parts in the projected image. The detected candidate regions go into a structure grouping process to eliminate false-positive detections. Finally, the scale and position of the patient relative to the projected figure are estimated based on the detected body parts via a structural voting. The start and end lines of the CT scan are projected to a standard human figure. The position readout is normalized so that the bottom of the feet represents 0.0, and the top of the head is 1.0. Classifiers for 18 body parts were trained using 184 CT scans. The final application was tested on 136 randomly selected heterogeneous CT scans. Ground truth was generated by asking two human observers to mark the start and end positions of each scan on the standard human figure. When compared with the human observers, the mean absolute error of the proposed method is 1.2% (max: 3.5%) and 1.6% (max: 5.4%) for the start and end positions, respectively. We proposed a scan range estimation method using multiple body parts detection and relative structure position analysis. In our preliminary tests, the proposed method delivered promising results.

  20. Complications in CT-guided Procedures: Do We Really Need Postinterventional CT Control Scans?

    Energy Technology Data Exchange (ETDEWEB)

    Nattenmüller, Johanna, E-mail: johanna.nattenmueller@med.uni-heidelberg.de; Filsinger, Matthias, E-mail: Matthias_filsinger@web.de; Bryant, Mark, E-mail: mark.bryant@med.uni-heidelberg.de; Stiller, Wolfram, E-mail: Wolfram.Stiller@med.uni-heidelberg.de; Radeleff, Boris, E-mail: boris.radeleff@med.uni-heidelberg.de; Grenacher, Lars, E-mail: lars.grenacher@med.uni-heidelberg.de; Kauczor, Hans-Ullrich, E-mail: hu.kauczor@med.uni-heidelberg.de; Hosch, Waldemar, E-mail: waldemar.hosch@urz.uni-heidelberg.de [University Hospital Heidelberg, Department of Diagnostic and Interventional Radiology (Germany)

    2013-06-19

    PurposeThe aim of this study is twofold: to determine the complication rate in computed tomography (CT)-guided biopsies and drainages, and to evaluate the value of postinterventional CT control scans.MethodsRetrospective analysis of 1,067 CT-guided diagnostic biopsies (n = 476) and therapeutic drainages (n = 591) in thoracic (n = 37), abdominal (n = 866), and musculoskeletal (ms) (n = 164) locations. Severity of any complication was categorized as minor or major. To assess the need for postinterventional CT control scans, it was determined whether complications were detected clinically, on peri-procedural scans or on postinterventional scans only.ResultsThe complication rate was 2.5 % in all procedures (n = 27), 4.4 % in diagnostic punctures, and 1.0 % in drainages; 13.5 % in thoracic, 2.0 % in abdominal, and 3.0 % in musculoskeletal procedures. There was only 1 major complication (0.1 %). Pneumothorax (n = 14) was most frequent, followed by bleeding (n = 9), paresthesia (n = 2), material damage (n = 1), and bone fissure (n = 1). Postinterventional control acquisitions were performed in 65.7 % (701 of 1,067). Six complications were solely detectable in postinterventional control acquisitions (3 retroperitoneal bleeds, 3 pneumothoraces); all other complications were clinically detectable (n = 4) and/or visible in peri-interventional controls (n = 21).ConclusionComplications in CT-guided interventions are rare. Of these, thoracic interventions had the highest rate, while pneumothoraces and bleeding were most frequent. Most complications can be detected clinically or peri-interventionally. To reduce the radiation dose, postinterventional CT controls should not be performed routinely and should be restricted to complicated or retroperitoneal interventions only.

  1. Case of Neuro-Behcet's disease with an interesting CT scan picture

    Energy Technology Data Exchange (ETDEWEB)

    Sato, J.; Kamitani, H.; Masuzawa, H. (Kantoh Teishin Hospital, Tokyo (Japan)); Matsui, T.; Mizobe, M.

    1981-12-01

    A Case of Neuro-Behcet's disease with an interesting CT scan picture was reported. A 31-year-old man with a known history of Behcet's disease was transferred to the Kantoh-Teishin Hospital upon suspicion of a brain tumor in the basal ganglia. Right hemiparesis and mild dysarthria of three weeks' duration and long-standing bilateral blindness were noted. Computerized tomography (CT) demonstrated an enhanced mass in the basal ganglia and surrounding irregular, low-density area in the white matter of the left frotoparietal lobe. The ventricles were shifted to the right. Left carotid angiography revealed a shift of the anterior cerebral artery to the right and a mild deformity of the Sylvian triangle. No tumor stain or abnormal vessels were seen. After high doses of prednisolone, his condition gradually improved. A CT scan two weeks later revealed a decrease in the low-density area and the mass effect, but an unchanged pathological contrast enhancement in the basal ganglia. The contrast enhancement lasted for two months. The CT scan of Neuro-Behcet's disease was discussed.

  2. CT Scan Features of Presumptive Haemorrhagic Stroke in a Dog with Cushing’s Disease

    Directory of Open Access Journals (Sweden)

    A. Liotta

    2014-01-01

    Full Text Available A 9-year-old, intact male, Brie’s shepherd dog, with a 10-day history of depression and tachypnoea developed signs of central neurological dysfunction. 16 Multislice Computed Tomography (CT pre- and postcontrast studies of the brain revealed a single intra-axial homogeneous well-circumscribed hyperattenuating (+/− 62 HU and noncontrast-enhancing area, 5 mm in diameter, in the caudal part of the mesencephalon. This finding was highly suggestive of a haemorrhagic event. A pituitary-dependent hyperadrenocorticism (PDH was identified and is considered likely to be the underlying cause. A repeat CT scan examination, 2 months later, showed almost complete resolution of the brain lesion. The present case describes a solitary 5 mm diameter lesion: the result of intracranial haemorrhage in a dog with presumed PDH.

  3. Automated Quantification of Stroke Damage on Brain Computed Tomography Scans: e-ASPECTS

    Directory of Open Access Journals (Sweden)

    James Hampton-Till

    2015-08-01

    Full Text Available Emergency radiological diagnosis of acute ischaemic stroke requires the accurate detection and appropriate interpretation of relevant imaging findings. Non-contrast computed tomography (CT provides fast and low-cost assessment of the early signs of ischaemia and is the most widely used diagnostic modality for acute stroke. The Alberta Stroke Program Early CT Score (ASPECTS is a quantitative and clinically validated method to measure the extent of ischaemic signs on brain CT scans. The CE-marked electronic-ASPECTS (e-ASPECTS software automates the ASPECTS score. Anglia Ruskin Clinical Trials Unit (ARCTU independently carried out a clinical investigation of the e-ASPECTS software, an automated scoring system which can be integrated into the diagnostic pathway of an acute ischaemic stroke patient, thereby assisting the physician with expert interpretation of the brain CT scan. Here we describe a literature review of the clinical importance of reliable assessment of early ischaemic signs on plain CT scans, and of technologies automating these processed scoring systems in ischaemic stroke on CT scans focusing on the e-ASPECTS software. To be suitable for critical appraisal in this evaluation, the published studies needed a sample size of a minimum of 10 cases. All randomised studies were screened and data deemed relevant to demonstration of performance of ASPECTS were appraised. The literature review focused on three domains: i interpretation of brain CT scans of stroke patients, ii the application of the ASPECTS score in ischaemic stroke, and iii automation of brain CT analysis. Finally, the appraised references are discussed in the context of the clinical impact of e-ASPECTS and the expected performance, which will be independently evaluated by a non-inferiority study conducted by the ARCTU.

  4. Computed tomographic (CT) scans in cerebral palsy (CP)

    Energy Technology Data Exchange (ETDEWEB)

    Kolawole, T.M.; Patel, P.J. (King Saud Univ., Riyadh (Saudi Arabia). Dept. of Radiology); Mahdi, A.H. (King Saud Univ., Riyadh (Saudi Arabia). Dept. of Paediatrics)

    1989-11-01

    The CT findings in 120 cerebral palsied children are analysed. The 72.5% positive findings are correlated with the clinical types, as well as the aetiological basis for the cerebral palsy. The spastic type, 83.3% of the total number of children, had the highest positive findings. The yield was increased in children with seizures (91.3%) and those in the postnatal group (90%), as well as those with birth trauma and neonatal asphyxia (94%). The findings were those of atrophy in 30.8%, hydrocephalus, in 10%, infarct in 11.6%, porencephaly in 8.3% and others. The atropic changes and their patterns are explained. Treatable lesions, such as tumour, hydrocephalus, subdural haematoma, porencephaly and hygroma were identified in 22.5% of cases. It is concluded that CT scan is definitely efficacious in the management of cerebral palsied children. (orig.).

  5. Quality assurance of CT scanning for industrial applications

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch

    in the field of application on the two different areas have been carried out. Different reference objects have been developed and introduced for the manufacturing industry: step gauge, step cylinder and a cylindrical multi-material assembly. These objects can be used for correction of measurement errors...... in the CT model. Moreover, two reference objects are calibrated objects from the manufacturing industry: a threaded tube from the medical industry and a LEGO brick from the toy industry. Establishment of traceability for all objects is performed using coordinate measuring machines (CMMs) with known...... uncertainty. The stability has been documented for all reference objects except for the step cylinder and the cylindrical multi-material assembly. A design of experiment (DOE) was performed on measuring errors arising in a CT, in terms of material density and orientation of scanned step gauges. An analysis...

  6. Quantitative analysis of CT scan in degenerative diseases of the nervous system

    Energy Technology Data Exchange (ETDEWEB)

    Matsuoka, Yukihiko; Yamamoto, Hiroko; Sobue, Itsuro.

    1988-05-01

    Quantitative analysis was made on cranial CT scans of 142 patients with spinocerebellar degeneration (SCD), 16 with dentato-rubro-pallido-luysian atrophy (DRPLA), 12 with Huntington's chorea (HC), and four with chorea-acanthocytosis (CA). One hundred sex- and age-matched persons without any neurologic signs served as controls. Regarding parameters for atrophy in the infratentorial brain tissue, there was statistically significant difference between the SCD group and the control group. This indicated remarkable atrophy in the cerebellum and brain stem in SCD. According to subgroups of SCD, both bilateral atrophy of the pons and dilation of the prepontine cistern were significantly greater in the group of sporadic olivo-ponto-cerebellar atrophy than the group of Menzel type of olivo-ponto-cerebellar atrophy. The subgroup of hereditary spastic paraplegia had the mildest atrophy of the brain on CT, although there was still a significant atrophy compared with controls. In the DRPLA group, finding in the infratentorial brain tissue were similar to those in the SCD group. The HC group was characterized by having the greatest atrophy in the lateral ventricle, especially the caudate nuclei. Similar findings were seen in the CA group, although atrophy was generally mild. The results indicate the usefulness of quantitative analysis on CT in the diagnosis of degenerative diseases of the nervous system. (Namekawa, K.).

  7. Visual anatomical lung CT scan assessment of lung recruitability.

    Science.gov (United States)

    Chiumello, Davide; Marino, Antonella; Brioni, Matteo; Menga, Federica; Cigada, Irene; Lazzerini, Marco; Andrisani, Maria C; Biondetti, Pietro; Cesana, Bruno; Gattinoni, Luciano

    2013-01-01

    The computation of lung recruitability in acute respiratory distress syndrome (ARDS) is advocated to set positive end-expiratory pressure (PEEP) for preventing lung collapse. The quantitative lung CT scan, obtained by manual image processing, is the reference method but it is time consuming. The aim of this study was to evaluate the accuracy of a visual anatomical analysis compared with a quantitative lung CT scan analysis in assessing lung recruitability. Fifty sets of two complete lung CT scans of ALI/ARDS patients computing lung recruitment were analyzed. Lung recruitability computed at an airway pressure of 5 and 45 cm H(2)O was defined as the percentage decrease in the collapsed/consolidated lung parenchyma assessed by two expert radiologists using a visual anatomical analysis and as the decrease in not aerated lung regions using a quantitative analysis computed by dedicated software. Lung recruitability was 11.3 % (interquartile range 7.39-16.41) and 15.5 % (interquartile range 8.18-21.43) with the visual anatomical and quantitative analysis, respectively. In the Bland-Altman analysis, the bias and agreement bands between the visual anatomical and quantitative analysis were -2.9 % (-11.8 to +5.9 %). The ROC curve showed that the optimal cutoff values for the visual anatomical analysis in predicting high versus low lung recruitability was 8.9 % (area under the ROC curve 0.9248, 95 % CI 0.8550-0.9946). Considering this cutoff, the sensitivity, specificity, and diagnostic accuracy were 0.96, 0.76, and 0.86, respectively. Visual anatomical analysis can classify patients into those with high and low lung recruitability allowing more intensivists to get access to lung recruitability assessment.

  8. Diagnosis of small posterior fossa stroke on brain CT: effect of iterative reconstruction designed for brain CT on detection performance

    Energy Technology Data Exchange (ETDEWEB)

    Inoue, Taihei; Yoshida, Morikatsu; Yokoyama, Koichi [Amakusa Medical Center, Department of Radiology, Amakusa, Kumamoto (Japan); Nakaura, Takeshi; Hirata, Kenichiro; Kidoh, Masafumi; Oda, Seitaro; Utsunomiya, Daisuke; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Graduate School of Life Sciences, Kumamoto (Japan); Harada, Kazunori [Amakusa Medical Center, Department of Surgery, Kumamoto (Japan)

    2017-09-15

    In this study, we aimed to determine whether iterative model reconstruction designed for brain CT (IMR-neuro) would improve the accuracy of posterior fossa stroke diagnosis on brain CT. We enrolled 37 patients with ischaemic stroke in the posterior fossa and 37 patients without stroke (controls). Using axial images reconstructed using filtered back-projection (FBP) and IMR-neuro, we compared the CT numbers in infarcted areas, image noise in the pons, and contrast-to-noise ratios (CNRs) of infarcted and non-infarcted areas on scans subjected to IMR-neuro and FBP. To analyse the performance of hypo-attenuation detection, we used receiver-operating characteristic (ROC) curve techniques. The image noise was significantly lower (2.2 ± 0.5 vs. 5.1 ± 0.9 Hounsfield units, p < 0.01) and the difference in CNR between the infarcted and non-infarcted areas was significantly higher with IMR-neuro than with FBP (2.2 ± 1.7 vs. 4.0 ± 3.6, p < 0.01). Furthermore, the average area under the ROC curve was significantly higher with IMR-neuro (0.90 vs. 0.86 for FBP, p = 0.04). IMR-neuro yielded better image quality and improved hypo-attenuation detection in patients with ischaemic stroke. (orig.)

  9. The Necessity of Follow-Up Brain Computed-Tomography Scans: Is It the Pathology Itself Or Our Fear that We Should Overcome?

    Science.gov (United States)

    Öğrenci, Ahmet; Koban, Orkun; Ekşi, Murat; Yaman, Onur; Dalbayrak, Sedat

    2017-10-15

    This study aimed to make a retrospective analysis of pediatric patients with head traumas that were admitted to one hospital setting and to make an analysis of the patients for whom follow-up CT scans were obtained. Pediatric head trauma cases were retrospectively retrieved from the hospital's electronic database. Patients' charts, CT scans and surgical notes were evaluated by one of the authors. Repeat CT scans for operated patients were excluded from the total number of repeat CT scans. One thousand one hundred and thirty-eight pediatric patients were admitted to the clinic due to head traumas. Brain CT scan was requested in 863 patients (76%) in the cohort. Follow-up brain CT scans were obtained in 102 patients. Additional abnormal finding requiring surgical intervention was observed in only one patient (isolated 4th ventricle hematoma) on the control CTs (1% of repeat CT scans), who developed obstructive hydrocephalus. None of the patients with no more than 1 cm epidural hematoma in its widest dimension and repeat CT scans obtained 1.5 hours after the trauma necessitated surgery. Follow-up CT scans changed clinical approach in only one patient in the present series. When ordering CT scan in the follow-up of pediatric traumas, benefits and harms should be weighted based upon time interval from trauma onset to initial CT scan and underlying pathology.

  10. Evaluation of ultrafast CT scanning of the adult abdomen

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, H.I.; Gould, R.G.; Feuerstein, I.M.; Sigeti, J.S.; Lipton, M.J. (Univ. of California, San Francisco (USA))

    1989-07-01

    Various measures of image quality were compared from adult abdomen scans obtained with a subsecond computed tomographic (CT) scanner (Imatron Ultrafast C-100) and a conventional third-generation whole-body scanner (GE9800). Forty images from 13 patients scanned within 2 hours of each other on both scanners were evaluated with techniques standardized as much as possible for CT exposure factors and contrast enhancement. Two observers in consensus evaluated matched anatomic levels using standard window width and level settings. Each image was graded on a scale of 1 (worst) to 5 (best) for spatial resolution, image noise, and presence and type of artifacts. Overall image quality also was graded. Averaged scores were compared between the two scanners. In all categories, scores were slightly higher for the GE9800. However, the differences in spatial resolution, presence of artifacts, overall image quality were not significant using the sign test. There was a significant difference, in favor of the GE9800, in image noise. The types of artifacts differed; the GE9800 produced more motion artifacts from bowel and surgical clips and the Imatron C-100 produced more rib shadow artifacts projecting on the liver and spleen. While the GE9800 produced abdominal images of slightly superior quality in adults, the Imatron Ultrafast C-100 was shown to produce images suitable for routine abdominal imaging in adults.

  11. Brain CT to Assess Intracranial Pressure in Patients with Traumatic Brain Injury.

    Science.gov (United States)

    Pappu, Suguna; Lerma, Jesus; Khraishi, Tariq

    2016-01-01

    Morphologic features of computed tomography (CT) scans of the brain can be used to estimate intracranial pressure (ICP) via an image-processing algorithm. Clinically, such estimations can be used to prognosticate outcomes and avoid placement of invasive intracranial monitors in certain patients with severe traumatic brain injury. Features on a CT scan that may correlate with measurements of low ICP are sought. A measure is proposed that is a function of the distribution of cerebrospinal fluid (CSF) in and around the brain. In our method, we present an algorithm that semiautomatically segments brain parenchyma from CSF, and apply standard image processing calculations. The ratio of CSF volume to the size of the intracranial vault (ICV) or volume inside the skull, csf(v) /icv(v) is calculated and then plotted against the actual recorded ICP, yielding a relationship between the image features and ICP. We analyzed a total of 45 scans from 20 patients with severe traumatic brain injury (TBI). We showed that a ratio csf(v)/icv(v) > .034 correlates with an ICP < 20 mmHg (P = .0046). For csf(v)/icv(v) ≤ .034, a distinction between low and high ICP cannot be effectively estimated by this univariate measure. This method permits a noninvasive means of identifying patients who are low risk for having elevated ICP; by following Brain Trauma Foundation guidelines strictly such a patient may be subjected to an unnecessary, invasive procedure. This work is a promising pilot study that will need to be analyzed for a larger population. Copyright © 2015 by the American Society of Neuroimaging.

  12. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... hard time staying still, are claustrophobic or have chronic pain, you may find a CT exam to ... of soft tissue (particularly the brain, including the disease processes) are less visible on CT scans . CT ...

  13. Mid-ventilation CT scan construction from four-dimensional respiration-correlated CT scans for radiotherapy planning of lung cancer patients.

    Science.gov (United States)

    Wolthaus, Jochem W H; Schneider, Christoph; Sonke, Jan-Jakob; van Herk, Marcel; Belderbos, José S A; Rossi, Maddalena M G; Lebesque, Joos V; Damen, Eugène M F

    2006-08-01

    Four-dimensional (4D) respiration-correlated imaging techniques can be used to obtain (respiration) artifact-free computed tomography (CT) images of the thorax. Current radiotherapy planning systems, however, do not accommodate 4D-CT data. The purpose of this study was to develop a simple, new concept to incorporate patient-specific motion information, using 4D-CT scans, in the radiotherapy planning process of lung cancer patients to enable smaller error margins. A single CT scan was selected from the 4D-CT data set. This scan represented the tumor in its time-averaged position over the respiratory cycle (the mid-ventilation CT scan). To select the appropriate CT scan, two methods were used. First, the three-dimensional tumor motion was analyzed semiautomatically to calculate the mean tumor position and the corresponding respiration phase. An alternative automated method was developed to select the correct CT scan using the diaphragm motion. Owing to hysteresis, mid-ventilation selection using the three-dimensional tumor motion had a tumor position accuracy (with respect to the mean tumor position) better than 1.1 +/- 1.1 mm for all three directions (inhalation and exhalation). The accuracy in the diaphragm motion method was better than 1.1 +/- 1.1 mm. Conventional free-breathing CT scanning had an accuracy better than 0 +/- 3.9 mm. The mid-ventilation concept can result in an average irradiated volume reduction of 20% for tumors with a diameter of 40 mm. Tumor motion and the diaphragm motion method can be used to select the (artifact-free) mid-ventilation CT scan, enabling a significant reduction of the irradiated volume.

  14. Open source deformable image registration system for treatment planning and recurrence CT scans

    DEFF Research Database (Denmark)

    Zukauskaite, Ruta; Brink, Carsten; Hansen, Christian Rønn

    2016-01-01

    CT) images of head and neck squamous cell carcinoma (HNSCC) patients was evaluated. PATIENTS AND MATERIALS: Twenty patients treated with definitive IMRT for HNSCC in 2010-2012 were included. For each patient, a pCT and an rCT scan were used. Median interval between the scans was 8.5 months. One observer...... on pCT. DSC for DIR varied between 0.58 and 0.79 for soft tissues and was 0.79 or higher for bony structures, and correlated with the volumes of ROIs (r = 0.5, p CT scans is feasible...

  15. Brain Scans Spot Where Fear and Anxiety Live

    Science.gov (United States)

    ... 165713.html Brain Scans Spot Where Fear and Anxiety Live Unusually large 'striatum' is linked to inability ... Scientists say they have found where fear and anxiety reside in the brain. The findings could lead ...

  16. Accuracy of limited four-slice CT-scan in diagnosis of chronic rhinosinusitis.

    Science.gov (United States)

    Zojaji, R; Nekooei, S; Naghibi, S; Mazloum Farsi Baf, M; Jalilian, R; Masoomi, M

    2015-12-01

    Chronic rhinosinusitis (CRS) is a common chronic health condition worldwide. Standard CT-scan is the method of choice for diagnosis of CRS but its high price and considerable radiation exposure have limited its application. The main goal of this study was to evaluate the accuracy of limited four-slice coronal CT-scan in the diagnosis of CRS. This cross-sectional study was conducted on 46 patients with CRS, for one year, based on American Society of Head and Neck Surgery criteria. All patients received the preoperative standard and four-slice CT-scans, after which endoscopic sinus surgery was performed. Findings of four-slice CT-scans were compared with those of conventional CT-scan and the sensitivity and specificity of four-slice CT-scan and its agreement with conventional CT-scan was calculated. In this study, 46 patients including 32 males (69.6%) and 14 females (30.46%) with a mean age of 33 and standard deviation of 9 years, were evaluated. Sensitivity and specificity of four-slice CT-scan were 97.5% and 100%, respectively. Also, positive predictive value (PPV) and negative predictive value (NPV) of four-slice CT was 100% and 85.71%, respectively. There was a strong agreement between four-slice CT and conventional CT findings. Considering the high sensitivity and specificity of four-slice CT-scan and strong agreement with conventional CT-scan in the diagnosis of CRS and the lower radiation exposure and cost, application of this method is suggested for both diagnosis and treatment follow-up in CRS. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  17. Case of pycnodysostosis. Observation of skull by CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Anegawa, Shigetaka; Bekki, Yoshiaki; Furukawa, Yasuhiro; Yokota, Seishi; Torigoe, Ryuichiro

    1987-07-01

    A 13-year-old boy was presented to the Department of Neurosurgery, Saiseikai Fukuoka General Hospital for further examinations concerning abnormal findings in the skull radiogram taken when he struck his head. His physical features showed some characteristics the same as those of pycnodysostosis as follows - proportionate dwarfism, prominent forehead, short spoon-shaped fingers, bilateral exophthalmos. A skull radiogram revealed widely open cranial sutures with no healing of the fracture and craniotomy which was performed for an acute epidural hematoma 6 years ago. Furthermore, the mandible was hypoplastic with a virtural loss of mandibular angle. CT of the soft tissues showed somewhat dilated cortical sulci and ventricles without any structural abnormalities in the brain. CT of bone algorythum revealed specific characteristics of this disease. The paranasal sinuses were quite hypoplastic. Especially in the maxillary sinuses, frontal sinussus and mastoid air cells, none of developments of sinuses were noted, even though the middle and internal ear seemed to be normal. Moreover, the ethomoid and sphenoid sinuses were noted, although their developments were poor. The appearance of skull base was normal, including the inlets and outlets of cranial nerves or vessels and synchondroses. However, the density of the skull base, especially in the diploe, was higher than normal in Hansfield number. Furthermore, detailed measurements of skull base demonstrated that the skull base itself was also dwarfish. In our study, the development of sinuses in bones with intramembranous ossification are worse than that with endochondral ossification. Furthermore, sutures or synchondroses in the skull base were well-developed than those of the convex. So, it is considered that pycnodysostosis must be the neighboring entity of diseases such as achondroplastic dwarfism or cleidocranial dysplasia. (J.P.N.).

  18. 68Gallium-DOTATATE PET/CT Scanning Results in Patients with MEN1

    Science.gov (United States)

    Sadowski, Samira M; Millo, Corina; Cottle-Delisle, Candice; Merkel, Roxanne; Yang, Lily A; Herscovitch, Peter; Pacak, Karel; Simonds, William F; Marx, Stephen J; Kebebew, Electron

    2015-01-01

    Background Screening for neuroendocrine tumors (NETs) in patients with multiple endocrine neoplasia type 1 (MEN1) is recommended to detect primary and metastatic tumors, which can result in significant morbidity and mortality. The utility of somatostatin receptor imaging 68Gallium-DOTATATE PET/CT in patients with MEN1 is not known. The aim of this study was to prospectively determine the accuracy of 68Gallium-DOTATATE PET/CT versus 111In-pentetreotide SPECT/CT and anatomic imaging in patients with MEN1. Study design Prospective study comparing 68Gallium-DOTATATE PET/CT, 111In-pentetreotide SPECT/CT, and triphasic CT scan to clinical, biochemical and pathological data in 26 patients with MEN1. Results 68Gallium-DOTATATE PET/CT detected 107 lesions; 111In- pentetreotide SPECT/CT detected 33 lesions; and CT scan detected 48 lesions. Lesions detected on 68Gallium-DOTATATE PET/CT had high SUVmax (median SUVmax = 72.8 [range 19–191]). In 7 of the 26 patients (27%), 68Gallium-DOTATATE PET/CT was positive with a negative 111In-pentetreotide SPECT/CT, and in 10 patients (38.5%), additional metastases were detected (range 0.3 cm to 1.5 cm). In 8 of the 26 patients (31%), there was a change in management recommendations as a result of the findings on 68Gallium-DOTATATE PET/CT that were not seen on 111In- pentetreotide SPECT/CT and CT scan. Conclusions 68Gallium-DOTATATE PET/CT is more sensitive for detecting NETs than 111In-pentetreotide SPECT/CT and CT scan in patients with MEN1. This imaging technique should be integrated into radiologic screening and surveillance of patients with MEN1, as it can significantly alter management recommendations. PMID:26206648

  19. Tc-99m HMPAO brain SPECT scanning in Munchausen syndrome.

    Science.gov (United States)

    Mountz, J M; Parker, P E; Liu, H G; Bentley, T W; Lill, D W; Deutsch, G

    1996-01-01

    Regional cerebral blood flow was studied in a patient with Munchausen syndrome using high resolution Tc-99m HMPAO SPECT. The scan demonstrated marked hyperperfusion of the right hemithalamus. The cranial CT scan was normal. The abnormal right hemithalamic blood flow is discussed in relation to the hypothesized neuropathy of this disorder. Images Figure 1 Figure 2 Figure 3 PMID:8580117

  20. The presence and progression of emphysema in COPD as determined by CT scanning and biomarker expression

    DEFF Research Database (Denmark)

    Coxson, Harvey O; Dirksen, Asger; Edwards, Lisa D

    2013-01-01

    Emphysema is a key contributor to airflow limitation in chronic obstructive pulmonary disease (COPD) and can be quantified using CT scanning. We investigated the change in CT lung density in a longitudinal, international cohort of patients with COPD. We also explored the potential relation between...... emphysema and patient characteristics, and investigated if certain circulating biomarkers were associated with decline in CT lung density....

  1. Impact of low-dose CT scan in dual timepoint investigations: a phantom study

    DEFF Research Database (Denmark)

    Micheelsen, M A; Jensen, Mikael

    2011-01-01

    compromising attenuation correction, lesion detection and quantification. Using a standard NEMA phantom with the GE Discovery PET/CT scanner, taken in and out between scan sessions, we have tried to find the minimal CT dose necessary for the second scan while still reaching tissue activity quantification...

  2. Adherence to follow-up CT scans in patients with small pulmonary nodules, a retrospective study

    DEFF Research Database (Denmark)

    Johansson, Sofie Lock; Gerner Hansen, Niels-Christian

    2010-01-01

    Adherence to follow-up CT scans in patients with small pulmonary nodules, a retrospective study The Danish National guidelines have since 2008 suggested serial follow-up CT scans at 3, 6, 12, and 24 months for nodules between 5 and 10 mm and at 12 and 24 months for nodules less than 5 mm...

  3. Detailed Review of CT Scans Aids Assessment of the Airway in ...

    African Journals Online (AJOL)

    Two cases are presented that illustrate the importance of information gained from CT scans of the head and neck taken in patients presenting for maxillo-facial surgery. The first case involved a 25 year old with a massive tumour filling his mouth. Pre-operative assessment was done without reviewing the CT scans of his ...

  4. Utility of CT Scan and CA 19-9 in Predicting Non –Resectability in ...

    African Journals Online (AJOL)

    Methods: Eligible consenting patients were recruited. All had a CT scan of the abdomen and serum CA 19-9 levels determined preoperatively and staging was done using the LRCC criteria. At surgery, intraoperative findings were then compared in terms of non-resectability with the preoperative CT scan prediction and the ...

  5. CT scan in severe diffuse head injury: physiological and clinical correlations.

    OpenAIRE

    Teasdale, E.; Cardoso, E.; Galbraith, S; Teasdale, G

    1984-01-01

    CT scan findings, clinical features and intracranial pressure were studied in patients with severe diffuse head injury. Compression of the 3rd ventricle and basal cisterns closely correlated with an intracranial pressure greater than 20 mmHg, with clinical signs of midbrain dysfunctions and worse prognosis. These CT scan findings can indicate whether intracranial pressure monitoring is appropriate.

  6. Accuracy of cancellous bone volume fraction measured by micro-CT scanning

    DEFF Research Database (Denmark)

    Ding, Ming; Odgaard, A; Hvid, I

    1999-01-01

    which covered a large range of volume fraction (9.8-39.8%) were produced. The specimens were micro-CT scanned, and the volume fraction based on Archimedes' principle was determined as a reference. After scanning, all micro-CT data were segmented using individual thresholds determined by the scanner...

  7. Effect of Work Improvement for Promotion of Outpatient Satisfaction on CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Han, Man Seok; Kim, Tae Hyung [Dept. of Radiological Science, Kangwon National University, Chuncheon (Korea, Republic of); Lee, Seung Youl; Lee, Myeong Goo; Jeon, Min Cheol [Dept. of Radiology, Chungnam National University Hospital, Daejeon (Korea, Republic of); Cho, Jae Hwan [Dept. of Radiological Science, Gyeongsan University College, Daegu (Korea, Republic of)

    2012-03-15

    Nowadays, most of the hospital serves 'one stop service' for CT scan. The patients could be taken the CT scan in the day they register for scan. On the contrary to the time convenience, patients are not satisfied with long waiting time and unkindness of staff. The objective of this study is to improve the patient's satisfaction for the CT scan, by analyzing inconvenience factors and improving the service qualities. From April 1 to August 30 in 2011, we investigated the satisfaction of patients who did examined abdomen CT scan with contrast media. We analyzed the 89 questionnaires before and after the service improvements from them. The worker's kindness, the environment of CT room and understanding about CT scan were answered by questionnaire and the waiting time of a day CT scan was drawn by medical information statistics. Also, the period before improvement was from April to June and the period after improvement was from July to September. And these questionnaire was analyzed through SPSS V. 15.0. In this study, kindness of staff, environment of CT room, intelligibility for CT scan and waiting time was explored and analyzed by SPSS V.15.0. The score of kindness was improved by 32%, satisfaction level of the environment was improved by 52.54%. The understanding level about CT scan was improved by 52.36% and the waiting time of a day CT was shortened by 21% through our service enhancement programs. Consequentially, it is considered that these efforts would contribute to increase the revenue of hospital.

  8. Body surface area determined by whole-body CT scanning: need for new formulae?

    DEFF Research Database (Denmark)

    Villa, Chiara; Primeau, Charlotte; Hesse, Ulrik

    2017-01-01

    Calculation of the estimated body surface area (BSA) by body height and weight has been a challenge in the past centuries due to lack of a well-documented gold standard. More recently, available techniques such as 3D laser surface scanning and CT scanning may be expected to quantify the BSA...... in an easier and more accurate way. This study provides the first comparison between BSA obtained from post-mortem whole-body CT scans and BSA calculated by nine predictive formulae. The sample consisted of 54 male cadavers ranging from 20 to 87 years old. 3D reconstructions were generated from CT scans using...

  9. The quality of three-dimensional images reconstructed with volume-scan CT

    Energy Technology Data Exchange (ETDEWEB)

    Shimbashi, Takeshi; Sakurai, Nobuaki; Watanabe, Norimitsu (Jikei Univ., Tokyo (Japan). School of Medicine); Takagi, Hiroshi; Takeuchi, Yutaka

    1993-05-01

    Volume-scan CT is based on slip-ring technology which leads to continuous scanning. It permits remarkable reduction in scanning time, which is especially meaningful where children and elderly patients are concerned. One scan takes one second, with a maximum continuous time of 50 seconds. Slice widths of 2, 3, 5 and 100 mm can be selected and table changed from 1.5 to 20 mm/second. The reconstruction index is 1 to 10 mm, and reconstruction time about 10 seconds. As both the patient and table are moved simultaneously, it is possible to scan a wide area in a short time. Volume-scan CT is suitable for three-dimensional (3-D) images because of the good continuity of slices. The authors reconstructed 3-D phantom images using both ordinary CT and volume-scan CT, and then compared the quality of these images. Under the condition of 3 mm slice width and 3 mm/sec table speed, the 3-D images reconstructed with volume-scan CT were clearly better than those reconstructed using ordinary CT. The quality of both has improved after interpolation. In particular, the periorbital and zygomatic areas of 3-D images reconstructed with volume-scan CT are quite natural. When a phantom was scanned under the condition of 10 mm slice width and 10 mm/sec table speed, the quality of 3-D image reconstructed with ordinary CT was not sufficient to be distinct. Even under interpolation, the quality of image was not natural. Useful images could not be obtained when the phantom was moving. It was found that volume-scan CT is suitable for reconstruction of 3-D images. (author).

  10. Interobserver variability in visual evaluation of thoracic CT scans and comparison with automatic computer measurements of CT lung density

    DEFF Research Database (Denmark)

    Winkler Wille, Mathilde Marie; Thomsen, Laura Hohwü; Dirksen, Asger

    2012-01-01

    Introduction – Emphysema is defined by pathology, but is most precisely evaluated in vivo by computed tomography (CT). Aims – were to determine the reproducibility of visual evaluation of emphysema, i.e. the observer variability, and furthermore to compare the visual evaluations to automatic CT...... lung density measurements, i.e. densitometry. Methods – In a pilot study 60 CT scans were selected from a sample of 3980 CT scans from The Danish Lung Cancer Screening Trial (DLCST). The amount of emphysema in these scans was scored independently by two observers, who were blinded regarding clinical...... information. The lung was segmented automatically by in-house developed computer software, and the percentage of pixels below -950 HU was used as a surrogate marker for emphysema. The observer variability, as well as the correlation with the lung density measurements, was analysed using Spearman’s rank...

  11. CT scan findings in three cases of multiple sclerosis with homonymous hemianopsia

    Energy Technology Data Exchange (ETDEWEB)

    Arikado, Takuji; Ariga, Hiroko; Kase, Manabu; Nagata, Renpei; Tashiro, Kunio (Hokkaido Univ., Sapporo (Japan). School of Medicine)

    1983-11-01

    Three cases of clinically definite multiple sclerosis manifested homonymous hemianopsia. A 35-year-old female, in whom right optic neuritis developed as the initial symptom, manifested right homonymous hemianopsia 4 months later followed by cerebral symptoms another 4 months later. A 25-year-old male developed sudden brain stem and cerebellar symptoms associated with right abducens palsy and right homonymous hemianopsia. In a 26-year-old female developed right homonymous hemianopsia 13 years after the first attack of recurrent optic neuritis. CT-scan in these three cases revealed the presence of a ''plaque'' located in the white matter of the left occipital lobe in cases 1 and 2 and in the left peririgone white matter in case 3 as the causative lesion for the right homonymous hemianopsia. These findings indicate that the optic radiation may be involved in multiple sclerosis resulting in homonymous hemianopsia. CT scan is of value in determining the location of the affected intracranial lesion in multiple sclerosis.

  12. Spinal CT scan, 2. Lumbar and sacral spines

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Hiroshi (Aichi Medical Univ., Aichi (Japan))

    1982-08-01

    Plain CT described fairly accurately the anatomy and lesions of the lumbar and sacral spines on their transverse sections. Since hernia of the intervertebral disc could be directly diagnosed by CT, indications of myelography could be restricted. Spinal-canal stenosis of the lumbar spine occurs because of various factors, and CT not only demonstrated the accurate size and morphology of bony canals, but also elucidated thickening of the joints and yellow ligament. CT was also useful for the diagnosis of tumors in the lumbar and sacral spines, visualizing the images of bone changes and soft tissues on the trasverse sections. But the diagnosis of intradural tumors required myelography and metrizamide CT. CT has become important for the diagnosis of spinal and spinal-cord diseases and for selection of the route of surgical arrival.

  13. Can the Day 0 CT-scan predict the post-implant scanning? Results from 136 prostate cancer patients.

    Science.gov (United States)

    Cattani, Federica; Vavassori, Andrea; Comi, Stefania; Gherardi, Federica; Russo, Stefania; Orecchia, Roberto; Jereczek-Fossa, Barbara A

    2017-08-01

    Post-implant CT-scanning is an essential part of permanent prostate brachytherapy. However, the evaluation of post-implant CT dosimetry is not straightforward due to the edema that can modify the dose to the prostate and to the organs at risk. The aim of this study is to evaluate the impact of the timing of the post-implant CT-scan on the dosimetric results and to verify if the Day 0 scan findings can predict Day 50 scanning. 136 consecutive patients who received monotherapy with I-125 implants were selected for this study. Two sets of 8 dosimetric quality parameters corresponding to 2 different CT-scans (Day 0 and Day 50) were calculated and compared. The dosimetric parameters included are the percentage volume of the post-implant prostate receiving 80%, 100% and 150% of the prescribed dose, the doses covering 80% and 90% of the prostate volume and the Dose Homogeneity Index. The values of the dose covering 1cm3 of the rectum and urethra were assessed. All the dosimetric parameters of the Day 50 were higher than those of the Day 0 scan. Linear functions were obtained that calculate D90 and V100 values at Day 50 based on the Day 0 findings. Rectal and urethral parameters tended to be underestimated on Day 0 CT-scan relative to Day 50 based dosimetry. Predicting the Day 50 dosimetry from the Day 0 scan could be a possible alternative to a Day 50 scan only in specific situations, but with a degree of uncertainty in the predicted values. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  14. SU-F-I-32: Organ Doses from Pediatric Head CT Scan

    Energy Technology Data Exchange (ETDEWEB)

    Liu, H; Liu, Q; Qiu, J; Zhuo, W [Institute of Radiation Medicine Fudan University, Shanghai (China); Majer, M; Knezevic, Z; Miljanic, S [Radiation Chemistry and Dosimetry Laboratory, Ruder Boskovic Institute, Zagreb (Croatia); Hrsak, H [Clinical Hospital Centre Zagreb, Zagreb (Croatia)

    2016-06-15

    Purpose: To evaluate the organ doses of pediatric patients who undergoing head CT scan using Monte Carlo (MC) simulation and compare it with measurements in anthropomorphic child phantom.. Methods: A ten years old children voxel phantom was developed from CT images, the voxel size of the phantom was 2mm*2mm*2mm. Organ doses from head CT scan were simulated using MCNPX software, 180 detectors were placed in the voxel phantom to tally the doses of the represented tissues or organs. When performing the simulation, 120 kVp and 88 mA were selected as the scan parameters. The scan range covered from the top of the head to the end of the chain, this protocol was used at CT simulator for radiotherapy. To validate the simulated results, organ doses were measured with radiophotoluminescence (RPL) detectors, placed in the 28 organs of the 10 years old CIRS ATOM phantom. Results: The organ doses results matched well between MC simulation and phantom measurements. The eyes dose was showed to be as expected the highest organ dose: 28.11 mGy by simulation and 27.34 mGy by measurement respectively. Doses for organs not included in the scan volume were much lower than those included in the scan volume, thymus doses were observed more than 10 mGy due the CT protocol for radiotherapy covered more body part than routine head CT scan. Conclusion: As the eyes are superficial organs, they may receive the highest radiation dose during the CT scan. Considering the relatively high radio sensitivity, using shielding material or organ based tube current modulation technique should be encouraged to reduce the eye radiation risks. Scan range was one of the most important factors that affects the organ doses during the CT scan. Use as short as reasonably possible scan range should be helpful to reduce the patient radiation dose. This work was supported by the National Natural Science Foundation of China(11475047)

  15. The use of CT-scanning at the medicolegal external postmortem examination and at the forensic autopsy

    DEFF Research Database (Denmark)

    Leth, Peter Mygind

    2006-01-01

    Introduction: Can CT-scanning of deceased at the medico legal external examination improve the selection of cases to autopsy? Is CT-scanning a substitute or a supplement to the traditional forensic autopsy? Material: In 2006 60 deceased individuals from Southern Denmark (counties of Fyn...... and Sønderjylland) (15 females and 45 males) were CT-scanned before autopsy. Method: A double-blind prospective investigation of CT-scanning in autopsy cases. A multislice spiral CT-scanner (Siemens Somatom Spirit) was used. Data from the CT-scanning and the autopsy were registered in a computer database...... and compared. Results: The scanning could be performed in 10 minutes per case. In approximately a third of the cases the cause of death could be established by CT-scanning alone. CT-scanning was found to be most useful in cases of traumatic death, and was superior to autopsy in visualizing fractures...

  16. Diagnosis of gynecologic pelvic masses by CT scans. Analysis of accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Ito, H.; Kubo, A.; Takagi, Y. (Keio Univ., Tokyo (Japan). School of Medicine); Kinoshita, F.; Maekawa, A.

    1981-08-01

    Two hundred eighty four patients with gynecologic pelvic masses were evaluated with CT scans. Of the patients, 196 had subsequent surgical determination of abnormalities and pathological proof of diagnosis was obtained. Only these 196 patients were included in this study. The CT scans could provide correct diagnosis in 113 of 114 (99%) patients with benign uterine tumor and in all (100%) patients with either serous cystadenoma or dermoid cyst. However, evaluation of mucinous cystadenoma (44%) and endometriosis cyst (37%) by CT scan has some limitations. It was difficult to differentiate mucinous cystadenoma from ovarian carcinoma, because both lesions had partial multiloculation and solid-like areas in the cyst. The CT findings of endometriosis cyst had similarity with serous cystadenoma, and 5 of 8 patients with this disease were diagnosed as serous cystadenoma. Ovarian fibroma and endometrial cancer were also not determined by CT scans. CT identified 87% of patients with ovarian cancer, while false positive rate of this disease was 38% (8/21). In 6 of 13 patients with both of leiomyoma and ovarian cyst, CT was able to demonstrate ovarian lesions that were overlooked by bimanual examinations. The role of CT scanning in our clinical practice is discussed.

  17. Acquiring 4D thoracic CT scans using a multislice helical method

    Science.gov (United States)

    Keall, P. J.; Starkschall, G.; Shukla, H.; Forster, K. M.; Ortiz, V.; Stevens, C. W.; Vedam, S. S.; George, R.; Guerrero, T.; Mohan, R.

    2004-05-01

    Respiratory motion degrades anatomic position reproducibility during imaging, necessitates larger margins during radiotherapy planning and causes errors during radiation delivery. Computed tomography (CT) scans acquired synchronously with the respiratory signal can be used to reconstruct 4D CT scans, which can be employed for 4D treatment planning to explicitly account for respiratory motion. The aim of this research was to develop, test and clinically implement a method to acquire 4D thoracic CT scans using a multislice helical method. A commercial position-monitoring system used for respiratory-gated radiotherapy was interfaced with a third generation multislice scanner. 4D cardiac reconstruction methods were modified to allow 4D thoracic CT acquisition. The technique was tested on a phantom under different conditions: stationary, periodic motion and non-periodic motion. 4D CT was also implemented for a lung cancer patient with audio-visual breathing coaching. For all cases, 4D CT images were successfully acquired from eight discrete breathing phases, however, some limitations of the system in terms of respiration reproducibility and breathing period relative to scanner settings were evident. Lung mass for the 4D CT patient scan was reproducible to within 2.1% over the eight phases, though the lung volume changed by 20% between end inspiration and end expiration (870 cm3). 4D CT can be used for 4D radiotherapy, respiration-gated radiotherapy, 'slow' CT acquisition and tumour motion studies.

  18. A STUDY OF CORRELATION BETWEEN NASAL ENDOSCOPY AND CT SCAN IN CASES OF CHRONIC RHINOSINUSITIS

    Directory of Open Access Journals (Sweden)

    Arun Kumar

    2015-07-01

    Full Text Available BACKGROUND: The accurate diagnosis of Chronic Rhinosinusitis (CRS is still a challenge therefore, the American Academy of Otorhinolaryngology - Head and Neck Surgery (AAO - HNS 1 has met in a multidisciplinary encounter and formulated a consensus based on only clinical symptoms. The computed tomography (CT scan and the nasal endoscopy (NE were introduced to make an accurate diagnosis of CRS and verify the disease severity. AIM: The aim of this study is to make a correlation between nasal endoscopy and CT scan in cases of clinically diagnosed Chronic Rhinosinusitis patients. METHOD: A study was carried out on 90 patients at Jhalawar Medical College, Jhalawar (Raj. during Sept. 20 12 to Dec. 2014. Diagnostic Nasal Endoscopy and CT Scan PNS done in patients, suffering from Chronic Rhinosinusitis. As a classification instruments, Metson / Gliklich's classification was used to evaluate the tomographic diagnosis and the Stankiewicz / Chow' s classification to evaluate the endoscopic diagnosis of Chronic Rhinosinusitis. RESULTS: Our study showed high specificity of endoscopy in comparison to CT scan though CT scan results are more sensitive. CONCLUSION: Endoscopy can confirm a Chronic Rhinosi nusitis diagnosis, but cannot rule it out, and that CT should be performed in cases of suspected CRS even if mucopurulence is not noted on endoscopy. The CT scan and the nasal endoscopy making easier the treatment planning and the disease resolution.

  19. Whole-brain CT perfusion and CT angiography assessment of Moyamoya disease before and after surgical revascularization: preliminary study with 256-slice CT.

    Directory of Open Access Journals (Sweden)

    Jun Zhang

    Full Text Available BACKGROUND/AIMS: The 256-slice CT enables the entire brain to be scanned in a single examination. We evaluated the application of 256-slice whole-brain CT perfusion (CTP in determining graft patency as well as investigating cerebral hemodynamic changes in Moyamoya disease before and after surgical revascularization. METHODS: Thirty-nine cases of Moyamoya disease were evaluated before and after surgical revascularization with 256-slice CT. Whole-brain perfusion images and dynamic 3D CT angiographic images generated from perfusion source data were obtained in all patients. Cerebral blood flow (CBF, cerebral blood volume (CBV, time to peak (TTP and mean transit time (MTT of one hemisphere in the region of middle cerebral artery (MCA distribution and contralateral mirroring areas were measured. Relative CTP values (rCBF, rCBV, rTTP, rMTT were also obtained. Differences in pre- and post- operation perfusion CT values were assessed with paired t test or matched-pairs signed-ranks test. RESULTS: Preoperative CBF, MTT and TTP of potential surgical side were significantly different from those of contralateral side (P<0.01 for all. All graft patencies were displayed using the 3D-CTA images. Postoperative CBF, rCBF and rCBV values of surgical side in the region of MCA were significantly higher than those before operation (P<0.01 for all. Postoperative MTT, TTP, rMTT and rTTP values of the surgical side in the region of MCA were significantly lower than those before operation (P<0.05 for all. CONCLUSION: The 256-slice whole-brain CTP can be used to evaluate cerebral hemodynamic changes in Moyamoya disease before and after surgery and the 3D-CTA is useful for assessing the abnormalities of intracranial arteries and graft patencies.

  20. Estimated radiation exposure and cancer risk from CT and PET/CT scans in patients with lymphoma

    Energy Technology Data Exchange (ETDEWEB)

    Guttikonda, Ravi [Imaging Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Herts, Brian R., E-mail: hertsb@ccf.org [Imaging Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Dong, Frank [Imaging Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Baker, Mark E. [Imaging Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States); Fenner, Kathleen B.; Pohlman, Brad [Taussig Cancer Institute, Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195 (United States)

    2014-06-15

    Introduction: The purpose of this study was to estimate total effective dose and cancer risk related to treatment monitoring and surveillance computed tomography (CT) scans in a cohort of patients diagnosed with lymphoma. Methods: 76 patients with head, neck, chest, abdomen or pelvis CT and whole-body positron emission tomography (PET)/CT were identified from an institutional lymphoma database; this included 54 (71%) patients with non-Hodgkin and 22 (29%) patients with classical Hodgkin lymphoma. Average treatment and surveillance periods were 8 months (range, 3–14 mo) and 23 months (range, 1–40 mo), respectively. Radiation exposure was estimated from the dose-length product (DLP) for CT scans and milli-Curies and DLP for PET/CT scans. Cancer risk was estimated using the Biological Effects of Ionizing Radiation model. Results: During their treatment period, 45 patients had 161 CT exams and 39 patients had 73 PET/CT exams. Mean effective dose was 39.3 mSv (range, 7.1–100 mSv). During the surveillance period, 60 patients had 378 CT exams and 25 patients had 39 PET/CT exams. Mean effective dose was 53.2 mSv (range, 2.6–154 mSv). Seventeen of 76 (22.4%) patients had total cumulative doses greater than 100 mSv. The mean increase in estimated cancer risk was 0.40%; the greatest estimated risk to any one patient was 1.19%. Conclusion: Mean total effective dose and mean estimated cancer risk were low in patients with lymphoma undergoing serial imaging, suggesting that theoretical risks of radiation-induced cancer need not be a major consideration in radiologic follow-up.

  1. Selection of colon cancer patients for neoadjuvant chemotherapy by preoperative CT scan

    DEFF Research Database (Denmark)

    Nørgaard, Anne; Dam, Claus; Jakobsen, Anders

    2014-01-01

    invasion (ETI), nodal stage (N-stage), extramural venous invasion (EVI) and the distance from tumor to nearest retroperitoneal fascia (DRF) were retrospectively assessed on the CT scan and compared blindly with the results of the pathological examination, including evaluation of the criteria for adjuvant...... tomography (CT) in local staging of colon cancer correlated with histopathological parameters, including criteria for adjuvant chemotherapy. Material and methods. A total of 74 included patients had preoperative CT scans and surgical resection of their colon tumors. Tumor stage (T-stage), extramural tumor...... chemotherapy. Advanced tumors were defined as T3 with ETI ≥5 mm or T4. Results. Sixty-nine percent of the tumors were correctly T-staged by CT, 7% were overstaged and 24% were understaged. As to correct recognition of ETI on the CT scan, the observer was 73% accurate compared with histology (70% sensitivity...

  2. CT muscle scanning in the evaluation of patients with spinal muscular atrophy (SMA)

    Energy Technology Data Exchange (ETDEWEB)

    Sambrook, P.; Rickards, D.; Cumming, W.J.K.

    1988-12-01

    One hundred with spinal muscular atrophy (SMA) were assessed by CT scanning using a standardised technique. The spectrum of CT abnormality occurring in SMA was observed and by overall analysis the patients were divided into 4 groups. While the CT appearances of these groups correlated well with clinical assessment of severity of disease, the disease process was usually much more widespread than clinical examination suggested. CT abnormality was first observed in the leg and gluteal muscles, progressing to the posterior spinal, thigh, shoulder girdle and sternomastoid muscles. Hypertrophy of sartorius and gracilis was observed in a significant number of patients. Fascial planes were preserved in involved muscles in over half of the patients, even in late-stage disease. Asymmetrical muscle involvement was seen with increasing frequency as the disease process increased in extent as evaluated by CT scanning. There was no discernible difference in the CT appearances in those patients who clinically had limb-girdle, facioscapulohumeral or scapuloperoneal distribution of weakness.

  3. Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Eric H. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); Amigenics, Inc, Las Vegas, NV (United States); Roach, Cayce J. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); University of Nevada Las Vegas, School of Life Sciences, Las Vegas, NV (United States); Ringdahl, Erik N. [University of Nevada Las Vegas, Department of Psychology, Las Vegas, NV (United States); Wynn, Brad L. [Family Medicine Spokane, Spokane, WA (United States); DeChancie, Sean M.; Mann, Nathan D. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); Diamond, Alan S. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); Orrison, William W. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); University of Nevada School of Medicine, Department of Medical Education, Reno, NV (United States)

    2011-05-15

    Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies. CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console. Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv. Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures. (orig.)

  4. Acquisition, preprocessing, and reconstruction of ultralow dose volumetric CT scout for organ-based CT scan planning

    Energy Technology Data Exchange (ETDEWEB)

    Yin, Zhye, E-mail: yin@ge.com; De Man, Bruno [Image Reconstruction Laboratory, GE Global Research, Niskayuna, New York 12309 (United States); Yao, Yangyang; Wu, Mingye [X-ray and CT Laboratory, GE Global Research, Shanghai 201203 (China); Montillo, Albert [Biomedical Image Processing Laboratory, GE Global Research, Niskayuna, New York 12309 (United States); Edic, Peter M. [CT, X-ray and Functional Imaging, GE Global Research, Niskayuna, New York 12309 (United States); Kalra, Mannudeep [Thoracic and Cardiac Imaging, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States)

    2015-05-15

    Purpose: Traditionally, 2D radiographic preparatory scan images (scout scans) are used to plan diagnostic CT scans. However, a 3D CT volume with a full 3D organ segmentation map could provide superior information for customized scan planning and other purposes. A practical challenge is to design the volumetric scout acquisition and processing steps to provide good image quality (at least good enough to enable 3D organ segmentation) while delivering a radiation dose similar to that of the conventional 2D scout. Methods: The authors explored various acquisition methods, scan parameters, postprocessing methods, and reconstruction methods through simulation and cadaver data studies to achieve an ultralow dose 3D scout while simultaneously reducing the noise and maintaining the edge strength around the target organ. Results: In a simulation study, the 3D scout with the proposed acquisition, preprocessing, and reconstruction strategy provided a similar level of organ segmentation capability as a traditional 240 mAs diagnostic scan, based on noise and normalized edge strength metrics. At the same time, the proposed approach delivers only 1.25% of the dose of a traditional scan. In a cadaver study, the authors’ pictorial-structures based organ localization algorithm successfully located the major abdominal-thoracic organs from the ultralow dose 3D scout obtained with the proposed strategy. Conclusions: The authors demonstrated that images with a similar degree of segmentation capability (interpretability) as conventional dose CT scans can be achieved with an ultralow dose 3D scout acquisition and suitable postprocessing. Furthermore, the authors applied these techniques to real cadaver CT scans with a CTDI dose level of less than 0.1 mGy and successfully generated a 3D organ localization map.

  5. Significance of CT scan and color Doppler duplex ultrasound in the assessment of Abernethy malformation

    National Research Council Canada - National Science Library

    Nacif, Lucas Souto; Paranaguá-Vezozzo, Denise Cerqueira; Galvão, Flávio Henrique Ferreira; Rocha, Manoel S; Andraus, Wellington; Carrilho, Flair Jose; D'Albuquerque, Luiz Carneiro

    2015-01-01

    .... In this study we highlight the significance of the use of CT scans and Color Doppler Duplex Ultrasound for the diagnosis, treatment and evolution assessment in two adults with Abernethy malformation...

  6. Coronal CT scan of paranasal sinuses; Long survey after Caldwell-Luc operation

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Atsuko (Tokyo Metropolitan Komagome Hospital (Japan)); Ikeda, Motohisa; Watanabe, Isamu; Komatsuzaki, Atsushi

    1994-03-01

    The clinical features were correlated with the coronal CT scan appearance of the paranasal sinuses of 49 patients who had received the Caldwell-Luc operation 16 to 58 years ago. The clinical diagnosis at the time of the CT scan was postoperative maxillary cyst in 22 patients, chronic sinusitis in 21 patients, trigeminal neuralgia in 3 patients, radicular cyst, postoperative ethmoid cyst and inverted papilloma in one patient each. The CT scans of the 91 operated maxillary sinuses showed obliterated cavity in 21 cases, small cavity in 46 cases, and cystic formation in 24 cases. The authors speculated that some maxillary sinuses which appeared in CT scans as small cavities might cause the clinical symptoms of postoperative maxillary cyst in the future. (author).

  7. Orbital cellulitis complicating isolated unilateral sphenoidal sinusitis: importance of the CT scan.

    Science.gov (United States)

    Roberts, C; Nylander, A E; Jayaramachandran, S

    1989-01-01

    A case of orbital cellulitis complicating the rare isolated unilateral sphenoidal sinusitis is reported, stressing the importance of a CT scan where plain x-rays fail to show any abnormality. Images PMID:2804035

  8. Micro computed tomography (CT) scanned anatomical gateway to insect pest bioinformatics

    Science.gov (United States)

    An international collaboration to establish an interactive Digital Video Library for a Systems Biology Approach to study the Asian citrus Psyllid and psyllid genomics/proteomics interactions is demonstrated. Advances in micro-CT, digital computed tomography (CT) scan uses X-rays to make detailed pic...

  9. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... which may be causing hearing problems. determine whether inflammation or other changes are present in the paranasal ... CT scans . CT is not sensitive in detecting inflammation of the meninges —the membranes covering the brain. ...

  10. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... soft tissue (particularly the brain, including the disease processes) are less visible on CT scans . CT is ... possible charges you will incur. Web page review process: This Web page is reviewed regularly by a ...

  11. Rapid Response: To Scan or Not to Scan? The Utility of Noncontrast CT Head for Altered Mental Status.

    Science.gov (United States)

    Thacker, Purujit J; Sethi, Mansha; Sternlieb, Jonathan; Schneider, Doron; Naglak, Mary; Patel, Rajeshkumar R

    2018-01-17

    The aims of the study were the following: (1) to determine how often computed tomography (CT) scans of the head are obtained on rapid responses called for altered mental status (AMS), (2) to determine whether CT imaging of the head is required during all rapid responses called for AMS, (3) to determine which patients would benefit from CT scans of the head in this setting, (4) to note whether an adequate neurologic exam was documented, (5) to determine the cost of CT scans that did not change management, and (6) to examine the role of medications leading to AMS. The study was a retrospective chart review at Abington Jefferson Hospital. Data collected included the age, sex, time of rapid response, clinical condition of the patient, whether an arterial blood gas and blood glucose were done, and whether a neurological exam was documented in the resident's rapid response team note. The patient's medications were also reviewed. Computed tomography scan findings as well as changes made in a patient's care as a result of the scan were recorded. Any findings that did not lead to a change in management were considered a "negative" scan. Overall, 610 rapid responses were activated from January to August 2016. One hundred four (17.04%) of the total rapid responses were for AMS and 83 (79.8%) of these patients underwent noncontrast CT scan of the head. The mean (SD) age of the patients was 74.7 (13.6) years. A total of 56.6% were female. The most frequent clinical conditions documented at the time of rapid responses were noted as confused (33.7%, 28/83), either lethargic or unconscious (32.5%, 27/83), and concern for stroke (21.7%, 18/83). A total of 96.4% (80/83) of the CT scans done were negative for any acute changes. The three patients with positive scans (3/83) had a change in management as a result of the scans. If patients with symptoms concerning for stroke and unconscious patients are excluded, the total number of remaining patients is 56. Of these, zero patients had

  12. Scan-rescan reproducibility of CT densitometric measures of emphysema

    Science.gov (United States)

    Chong, D.; van Rikxoort, E. M.; Kim, H. J.; Goldin, J. G.; Brown, M. S.

    2011-03-01

    This study investigated the reproducibility of HRCT densitometric measures of emphysema in patients scanned twice one week apart. 24 emphysema patients from a multicenter study were scanned at full inspiration (TLC) and expiration (RV), then again a week later for four scans total. Scans for each patient used the same scanner and protocol, except for tube current in three patients. Lung segmentation with gross airway removal was performed on the scans. Volume, weight, mean lung density (MLD), relative area under -950HU (RA-950), and 15th percentile (PD-15) were calculated for TLC, and volume and an airtrapping mask (RA-air) between -950 and -850HU for RV. For each measure, absolute differences were computed for each scan pair, and linear regression was performed against volume difference in a subgroup with volume difference emphysema treatment efficacy.

  13. Detectability of cerebral aneurysms and surrounding vessels by three-dimensional evaluation using helical scanning CT (HES-CT)

    Energy Technology Data Exchange (ETDEWEB)

    Ogura, Yuko; Katada, Kazuhiro; Sano, Hirotoshi; Kato, Yoko; Kanno, Tetsuo; Takeshita, Gen; Koga, Sukehiko (Fujita Health Univ., Toyoake, Aichi (Japan))

    1994-09-01

    Helical scanning CT (HES-CT) is a new technique to enable high-speed volumetric data acquisition. We have applied HES-CT to the diagnosis of cerebral vascular diseases. In our experience, the relationship between the scanning parameters of HES-CT and image quality was complex and reciprocal, so that optimization of the parameters according to the clinical demands was essential. We compared HES-CT with conventional cerebral angiography to determine the detectability of the aneurysm and surrounding vessels, and sought the optimal parameters to delineate small vessels. All aneurysms were detected in multiplanar reconstruction (MPR) images. The smallest one was 3 x 4 mm. MPR images were found to have some advantages over conventional cerebral angiography in delineation of intracranial aneurysms: (1) scanning was over in a short time (30 s), (2) the relationship between the aneurysm and surrounding vessels was easily recognized, (3) the diameter of the neck could be measured, because the neck of the aneurysm and parent artery could be imaged on the same plane without overlapping another vessel, (4) calcified lesions on the aneurysmal wall were detected, and (5) HES-CT was done safety without arterial puncture. However, the detectability of unknown aneurysm was less than the detectability of known aneurysm in MPR images. The 180deg interpolation algorithm and 1 mm slice were effective in detecting small vessels. However, vessels with a diameter less than 1 mm could not be detected by HES-CT. HES-CT was considered to be useful as a supplementary examination to conventional angiography for the diagnosis of intracranial aneurysms. (author).

  14. Are CT scans obtained at referring institutions justified prior to transfer to a pediatric trauma center?

    Science.gov (United States)

    Benedict, Leo Andrew; Paulus, Jessica K; Rideout, Leslie; Chwals, Walter J

    2014-01-01

    To assess whether pediatric trauma patients initially evaluated at referring institutions met Massachusetts statewide trauma field triage criteria for stabilization and immediate transfer to a Pediatric Trauma Center (PTC) without pre-transfer CT imaging. A 3-year retrospective cohort study was completed at our level 1 PTC. Patients with CT imaging at referring institutions were classified according to a triage scheme based on Massachusetts statewide trauma field triage criteria. Demographic data and injury profile characteristics were abstracted from patient medical records and our pediatric trauma registry. A total of 262 patients with 413 CT scans were reviewed from 2008 to 2011. 172 patients scanned (66%, 95% CI: 60%, 71%) met criteria for immediate transfer to a pediatric trauma center. Notably, 110 scans (27% of the total performed at referring institutions) were duplicated within four hours upon arrival to our PTC. GCS score transfer, and CT scan of the head was the most frequent scan obtained (53%). The majority of pediatric trauma patients were subjected to CT scans at referring institutions despite meeting Massachusetts trauma triage guidelines that call for stabilization and immediate transfer to a pediatric trauma center without any CT imaging. © 2014.

  15. Dual energy CT with one full scan and a second sparse-view scan using structure preserving iterative reconstruction (SPIR)

    Science.gov (United States)

    Wang, Tonghe; Zhu, Lei

    2016-09-01

    Conventional dual-energy CT (DECT) reconstruction requires two full-size projection datasets with two different energy spectra. In this study, we propose an iterative algorithm to enable a new data acquisition scheme which requires one full scan and a second sparse-view scan for potential reduction in imaging dose and engineering cost of DECT. A bilateral filter is calculated as a similarity matrix from the first full-scan CT image to quantify the similarity between any two pixels, which is assumed unchanged on a second CT image since DECT scans are performed on the same object. The second CT image from reduced projections is reconstructed by an iterative algorithm which updates the image by minimizing the total variation of the difference between the image and its filtered image by the similarity matrix under data fidelity constraint. As the redundant structural information of the two CT images is contained in the similarity matrix for CT reconstruction, we refer to the algorithm as structure preserving iterative reconstruction (SPIR). The proposed method is evaluated on both digital and physical phantoms, and is compared with the filtered-backprojection (FBP) method, the conventional total-variation-regularization-based algorithm (TVR) and prior-image-constrained-compressed-sensing (PICCS). SPIR with a second 10-view scan reduces the image noise STD by a factor of one order of magnitude with same spatial resolution as full-view FBP image. SPIR substantially improves over TVR on the reconstruction accuracy of a 10-view scan by decreasing the reconstruction error from 6.18% to 1.33%, and outperforms TVR at 50 and 20-view scans on spatial resolution with a higher frequency at the modulation transfer function value of 10% by an average factor of 4. Compared with the 20-view scan PICCS result, the SPIR image has 7 times lower noise STD with similar spatial resolution. The electron density map obtained from the SPIR-based DECT images with a second 10-view scan has an

  16. Stroke scores and CT scan in ascertaining type of stroke. | Salawu ...

    African Journals Online (AJOL)

    Background: Stroke, a major cause of morbidity and mortality is on the increase in Nigeria, routine Computerized Tomography (CT) for all Nigerians with stroke is not available to most doctors, and this poses management problems. We compared two available clinical scores with brain CT for the differential diagnosis of ...

  17. Comparison of CT and MRI brain tumor imaging using a canine glioma model.

    Science.gov (United States)

    Whelan, H T; Clanton, J A; Wilson, R E; Tulipan, N B

    1988-01-01

    A canine gliosarcoma model was used to study the effectiveness of magnetic resonance imaging (MRI) with gadolinium contrast enhancement in defining the histologic margins of brain tumors. The effectiveness of this technique was compared to conventional computed tomography (CT) using iodinated contrast enhancement. Cultured canine gliosarcoma cells were injected into the left hemisphere of adult mongrel dogs. The dogs developed brain tumors and progressive clinical signs. Serial MRI with and without gadolinium diethylene triamine penta-acetic acid was compared to serial CT with and without sodium iothalamate obtained on the same days. After the final scans, animals were sacrificed; the brains were removed and processed for routine histopathologic study. All tumors were visualized with contrast-enhanced MRI which proved most sensitive. Gadolinium di-ethylene triamine penta-acetic acid caused bright enhancement of tumors in a distribution that consistently corresponded to areas of pathologically proved tumor infiltration. Gross and microscopic autopsy findings correlated better with MRI than with CT which tended to produce poorer resolution and underrepresent the size of viable tumor. Gadolinium-enhanced MRI is more accurate than unenhanced MRI, unenhanced CT, or enhanced CT in defining the histologic margins of tumors.

  18. Advantage of CT scan in muscular pathology. Personal cases and review of the literature

    Energy Technology Data Exchange (ETDEWEB)

    Laroche, M.; Rousseau, H.; Mazieres, B.; Bonafe, A.; Joffre, F.; Arlet, J.

    1989-05-01

    The advantage of CT scans in muscular pathology is studied. The scan, in addition to the diagnosis of tumors and muscular abscesses, permits to differentiate primary myopathies from neurogenic atrophies: in the course of myopathies, the muscle volume is preserved and they appear as a hypodensity; in neurogenic atrophies, the muscle volume is reduced with preserved density. The CT scan permits to determine the extension of these lesions. In the course of polymyositis, certain forms of rheumatid arthritis, the scan discloses a trabecular and 'worm-eaten' aspect of the muscles. This is also observed after long-term steroid therapy and other endocrine diseases (hyperthyroidism, osteomalacia) indicating an infra-clinical myopathy. In vertebral osteoporosis with fractures and patients with chronic lumbalgia, very ofter, an atrophy of the spinal muscle is observed. Finally, in the course of acquired kyphosis of the adult patient (camptocormia), the CT scan suggest an isolated myopathy, with late manifestations, of the paravertebral muscles.

  19. Efficacy of Lens Protection Systems: Dependency on Different Cranial CT Scans in The Acute Stroke Setting.

    Science.gov (United States)

    Guberina, Nika; Forsting, Michael; Ringelstein, Adrian

    2017-06-15

    To evaluate the dose-reduction potential with different lens protectors for patients undergoing cranial computed tomography (CT) scans. Eye lens dose was assessed in vitro (α-Al2O3:C thermoluminescence dosemeters) using an Alderson-Rando phantom® in cranial CT protocols at different CT scanners (SOMATOM-Definition-AS+®(CT1) and SOMATOM-Definition-Flash® (CT2)) using two different lens-protection systems (Somatex® (SOM) and Medical Imaging Systems® (MIS)). Summarised percentage of the transmitted photons: (1) CT1 (a) unenhanced CT (nCT) with gantry angulation: SOM = 103%, MIS = 111%; (2) CT2 (a) nCT without gantry angulation: SOM = 81%, MIS = 91%; (b) CT angiography (CTA) with automatic dose-modulation technique: SOM = 39%, MIS = 74%; (c) CTA without dose-modulation technique: SOM = 22%, MIS = 48%; (d) CT perfusion: SOM = 44%, MIS = 69%. SOM showed a higher dose-reduction potential than MIS maintaining equal image quality. Lens-protection systems are most effective in CTA protocols without dose-reduction techniques. Lens-protection systems lower the average eye lens dose during CT scans up to 1/3 (MIS) and 2/3 (SOM), respectively, if the eye lens is exposed to the direct beam of radiation. Considering both the CT protocol and the material of lens protectors, they seem to be mandatory for reducing the radiation exposure of the eye lens. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Simultaneous reconstruction and segmentation of CT scans with shadowed data

    DEFF Research Database (Denmark)

    Lauze, Francois Bernard; Quéau, Yvain; Plenge, Esben

    2017-01-01

    We propose a variational approach for simultaneous reconstruction and multiclass segmentation of X-ray CT images, with limited field of view and missing data. We propose a simple energy minimisation approach, loosely based on a Bayesian rationale. The resulting non convex problem is solved...

  1. Centre for Industrial Application of CT scanning (CIA-CT) – Four years of results 2009-2013

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo; Andreasen, Jan Lasson; Christensen, Lars Bager

    activities: Centre of Excellence, Dissemination, Collaboration, Research, and Initiation of new activities. The consortium has consisted of nine partners, including three research institutions, two consultancy partners, two large companies, and two small / medium enterprises. The consortium has acted......The innovation consortium project, carried out September 2009 – August 2013, has aimed to help the participating companies and Danish industry with the introduction of CT scanning as measuring technology, carrying out research at international level. The project has operated through five main...... as a centre of excellence for industrial CT scanning, both nationally and internationally. A network with approx. 40 participants has been established, and a total of 22 students have been educated. Dissemination activities have encompassed: a web page www.cia-ct.mek.dtu.dk , 8 newsletters, 4 topical...

  2. Relationship between Hounsfield Unit in CT Scan and Gray Scale in CBCT

    Directory of Open Access Journals (Sweden)

    Tahmineh Razi

    2014-06-01

    Full Text Available Background and aims. Cone-beam computed tomography (CBCT is an imaging system which has many advantages over computed tomography (CT. In CT scan, Hounsfield Unit (HU is proportional to the degree of x-ray attenuation by the tissue. In CBCT, the degree of x-ray attenuation is shown by gray scale (voxel value. The aim of the present study was to investigate the relationship between gray scale in CBCT and Hounsfield Unit (HU in CT scan. Materials and methods. In this descriptive study, the head of a sheep was scanned with 3 CBCT and one medical CT scanner. Gray scales and HUs were detected on images. Reconstructed data were analyzed to investigate relationship between CBCT gray scales and HUs. Results. A strong correlation between gray scales of CBCT and HUs of CT scan was determined. Conclusion. Considering the fact that gray scale in CBCT is the criteria in measurement of bone density before implant treatments, it is recommended because of the lower dose and cost compared to CT scan.

  3. An anatomically shaped lower body model for CT scanning of cadaver femurs.

    NARCIS (Netherlands)

    Tanck, E.J.M.; Deenen, J.C.W.; Huisman, H.J.; Kooloos, J.G.M.; Huizenga, H.; Verdonschot, N.J.J.

    2010-01-01

    Bone specific, CT-based finite element (FE) analyses have great potential to accurately predict the fracture risk of deteriorated bones. However, it has been shown that differences exist between FE-models of femora scanned in a water basin or scanned in situ within the human body, as caused by

  4. Repeated CT scans in trauma transfers: An analysis of indications, radiation dose exposure, and costs.

    Science.gov (United States)

    Hinzpeter, Ricarda; Sprengel, Kai; Wanner, Guido A; Mildenberger, Peter; Alkadhi, Hatem

    2017-03-01

    To identify the number of CT scans repeated in acute trauma patients receiving imaging before being referred to a trauma center, to define indications, and to assess radiation doses and costs of repeated CT. This retrospective study included all adult trauma patients transferred from other hospitals to a Level-I trauma center during 2014. Indications for repeated CT scans were categorized into: inadequate CT image data transfer, poor image quality, repetition of head CT after head injury together with completion to whole-body CT (WBCT), and follow-up of injury known from previous CT. Radiation doses from repeated CT were determined; costs were calculated using a nation-wide fee schedule. Within one year, 85/298 (28.5%) trauma patients were transferred from another hospital because of severe head injury (n=45,53%) and major body trauma (n=23;27%) not manageable in the referring hospital, repatriation from a foreign country (n=14;16.5%), and no ICU-capacity (n=3;3.5%). Of these 85 patients, 74 (87%) had repeated CT in our center because of inadequate CT data transfer (n=29;39%), repetition of head CT with completion to WBCT (n=24;32.5%), and follow-up of known injury (n=21;28.5%). None occurred because of poor image quality. Cumulative dose length product (DLP) and annual costs of potential preventable, repeated CT (inadequate data transfer) was 631mSv (81'304mGy*cm) and 35'233€, respectively. A considerable number of transferred trauma patients undergo potentially preventable, repeated CT, adding radiation dose to patients and costs to the health care system. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Sequential Change of Hypometabolic Metastasis from Non-small-cell Lung Cancer on Brain FDG-PET/CT

    Energy Technology Data Exchange (ETDEWEB)

    Park, Soon Ah; Yang, Sei Hoon; Yang, Chung Yong; Choi, Keum Ha [Wonkwang Medical Science, Wonkwang University College of Medicine, Iksan (Korea, Republic of)

    2009-10-15

    A 60-year-old woman, who had non-small-cell lung cancer (NSCLC) in left lower lobe underwent brain F-18 fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) for evaluation of cerebral metastasis. On follow-up FDG-PET/CT, only hypometaolic lesion was detected and progressed in right frontal lobe at 6 months and 10 months, later. Hypermetabolic metastasis was not detected even at last scan time of FDG-PET/CT. Brain MRI showed brain metastasis in right frontal lobe. As might be expected, the physician should take cerebral metastasis into consideration even though there is only hypometabolic change on subsequent FDG-PET/CT in patients with NSCLC.

  6. Pixel-wise estimation of noise statistics on iterative CT reconstruction from a single scan.

    Science.gov (United States)

    Wang, Tonghe; Zhu, Lei

    2017-07-01

    As iterative CT reconstruction continues to advance, the spatial distribution of noise standard deviation (STD) and accurate noise power spectrum (NPS) on the reconstructed CT images become important for method evaluation as well as optimization of algorithm parameters. Using a single CT scan, we propose a practical method for pixel-wise calculation of noise statistics on an iteratively reconstructed CT image, which enables accurate calculation of noise STD for each pixel and NPS. We first derive the noise propagation from measured projections to an iteratively reconstructed CT image provided that the projection noise is known. We then show that the model of noise propagation remains approximately unchanged for extra simulated noise added on the measured projections. To compute the noise STD map and the NPS map on an iteratively reconstructed CT image from a single scan, we first iteratively reconstruct the CT image from the measured projections using an existing reconstruction algorithm. The same measured projections are added by different sets (a total of 32 sets in our implementation) of projection noise simulated from an estimated projection noise model, and are then used to iteratively reconstruct different CT images. The calculations of the noise STD map and the NPS map are finally performed on the entire stack of these different reconstruction images. We evaluate our method on an anthropomorphic head phantom, and demonstrate the clinical utility on a set of head and neck patient CT data, using two iterative CT reconstruction algorithms: the penalized weighted least-square (PWLS) algorithm and the total-variation (TV) regularization. In the head phantom case, repeated scans are acquired to generate the ground truths of noise STD and NPS maps. Using only one single scan, the proposed method accurately calculates the noise STD maps with a root-mean-square error (RMSE) of less than 5HU. In the NPS map estimation, we compare the result of our proposed method with

  7. Evaluation of CT and MRI scanning among cancer patients in Ontario.

    Science.gov (United States)

    Coburn, Natalie; Przybysz, Raymond; Barbera, Lisa; Hodgson, David C; Laupacis, Andreas; Law, Calvin

    2011-01-01

    Computed tomography (CT) and magnetic resonance imaging (MRI) utilization in Ontario increased drastically since the early 1990s. The effect of an increased number of cancer diagnoses, and an increase in indications for scans has not been assessed. This study was conducted to determine trends in utilization of CT and MRI in cancer patients in Ontario over a period of 9 years. Using Ontario Health Insurance Plan billing data linked to the Ontario Cancer Registry, rates of CT and MRI were analyzed by region, year, scan type and socioeconomic status. CT in cancer patients increased 2.3-fold and accounted for approximately 24% of these scans. MRI in cancer patients increased by 4.2-fold and accounted for approximately 10% of these scans. Imaging rates for cancer patients increased more gradually than that of the general population. Substantial variation in the rate of both scans by region of patient residence existed. Even greater variation by the location of the scanner was demonstrated, indicating that many cancer patients traveled outside their region for imaging. There was little evidence of variation in scanning rates by socioeconomic status. A minority of CT and MRI performed in Ontario are for cancer care. Regional variation in imaging rates suggest that utilization guidelines be developed or knowledge transfer initiatives improve compliance to existing guidelines are needed. A significant number of cancer patients travel outside their region for diagnostic imaging; this should influence decisions about the location of new scanners. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Simultaneous Reconstruction and Segmentation of CT Scans with Shadowed Data

    DEFF Research Database (Denmark)

    Lauze, Francois Bernard; Quéau, Yvain; Plenge, Esben

    2017-01-01

    We propose a variational approach for simultaneous recon- struction and multiclass segmentation of X-ray CT images, with limited field of view and missing data. We propose a simple energy minimi- sation approach, loosely based on a Bayesian rationale. The resulting non convex problem is solved by...... by alternating reconstruction steps using an iterated relaxed proximal gradient, and a proximal approach for the segmentation. Preliminary results on synthetic data demonstrate the po- tential of the approach for synchrotron imaging applications....

  9. Gambaran CT Scan Toraks Sesuai dengan Jenis Sitologi/Histologi pada Pasien Kanker Paru yang Merokok

    Directory of Open Access Journals (Sweden)

    Rosa Tatun

    2016-03-01

    Full Text Available Kanker paru merupakan  penyebab kematian paling banyak akibat keganasan. Kanker paru memberikan gambaran CT scan yang berbeda sesuai dengan jenis sitologi/histologinya. Pemeriksaan CT scan  toraksdengan teknik high resolution computed tomography (HRCT dapat memperlihatkan kelainan kanker parusecara rinci. Penelitian dilakukan di Instalasi Radiologi RSU Persahabatan, Jakarta bekerja sama denganDepartemen Pulmonologi dan Respirasi RSU Persahabatan terhadap 100 sampel yang diperoleh pada bulanNovember 2014 hingga Maret 2015. Berdasarkan jenis sitologi/histologi kanker paru (adenokarsinoma dankarsinoma sel skuamosa/KSS tidak ditemukan  variabel yang bermakna secara statistik  (bentuk, letak, tepispikulasi, tepi lobulasi, nodul satelit. Variabel yang paling banyak ditemukan pada adenokarsinoma maupunKSS adalah bentuk massa, lokasi di sentral dan paru sebelah kanan. Gambaran kanker paru adenokarsinomadan KSS pada pasien merokok paling banyak berupa massa, lokasi di sentral dan lobus kanan paru. Kata kunci: kanker paru, merokok, CT scan toraks   Lung Cancer CT Scan Findings in Smoker Patients Basedon Cytology/Histology Abstract Lung cancer is the leading cause of most deaths due to malignancy. Lung cancer CT scan provides an overview according to the type of cytology / histology. Thorax CT scan with high resolution technique (HRCT may revealdetail lung cancer abnormalities. This study was conducted between Department of Radiology and Departmentof Pulmonology Respiratory, Persahabatan Hospital Jakarta based on 100 samples, November 2014 until March2015. Based on cytological/histological type (adenocarcinoma and squamous cell carcinoma/KSS, it was not found significant meaningfull variables (shape, location, spiculate edge, lobulate edge, satellite nodules. Most commonly variables found in adenocarcinomas and KSS were mass forming, central location, right lung location.Most of adenocarcinoma and SCC in smoked patients were mass forming, central

  10. Evaluation of geometrical effects of microneedles on skin penetration by CT scan and finite element analysis.

    Science.gov (United States)

    Loizidou, Eriketi Z; Inoue, Nicholas T; Ashton-Barnett, Johnny; Barrow, David A; Allender, Chris J

    2016-10-01

    Computerized tomography scan (CT scan) imaging and finite element analysis were employed to investigate how the geometric composition of microneedles affects their mechanical strength and penetration characteristics. Simulations of microneedle arrays, comprising triangular, square and hexagonal microneedle base, revealed a linear dependence of the mechanical strength to the number of vertices in the polygon base. A laser-enabled, micromoulding technique was then used to fabricate 3×3 microneedle arrays, each individual microneedle having triangular, square or hexagonal base geometries. Their penetration characteristics into ex-vivo porcine skin, were investigated for the first time by CT scan imaging. This revealed greater penetration depths for the triangular and square-based microneedles, demonstrating CT scan as a powerful and reliable technique for studying microneedle skin penetration. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Non-invasive transcranial ultrasound therapy based on a 3D CT scan: protocol validation and in vitro results

    Energy Technology Data Exchange (ETDEWEB)

    Marquet, F; Pernot, M; Aubry, J-F; Montaldo, G; Tanter, M; Fink, M [Laboratoire Ondes et Acoustique, ESPCI, Universite Paris VII, UMR CNRS 7587, 10 rue Vauquelin, 75005 Paris (France); Marsac, L [Supersonic Imagine, Les Jardins de la Duranne, 510 rue Rene Descartes, 13857 Aix-en-Provence (France)], E-mail: fabrice.marquet@espci.org

    2009-05-07

    A non-invasive protocol for transcranial brain tissue ablation with ultrasound is studied and validated in vitro. The skull induces strong aberrations both in phase and in amplitude, resulting in a severe degradation of the beam shape. Adaptive corrections of the distortions induced by the skull bone are performed using a previous 3D computational tomography scan acquisition (CT) of the skull bone structure. These CT scan data are used as entry parameters in a FDTD (finite differences time domain) simulation of the full wave propagation equation. A numerical computation is used to deduce the impulse response relating the targeted location and the ultrasound therapeutic array, thus providing a virtual time-reversal mirror. This impulse response is then time-reversed and transmitted experimentally by a therapeutic array positioned exactly in the same referential frame as the one used during CT scan acquisitions. In vitro experiments are conducted on monkey and human skull specimens using an array of 300 transmit elements working at a central frequency of 1 MHz. These experiments show a precise refocusing of the ultrasonic beam at the targeted location with a positioning error lower than 0.7 mm. The complete validation of this transcranial adaptive focusing procedure paves the way to in vivo animal and human transcranial HIFU investigations.

  12. Do CT scans overestimate the fusion rate after anterior cervical discectomy and fusion?

    Science.gov (United States)

    Park, Daniel K; Rhee, John M; Kim, Sung S; Enyo, Yoshio; Yoshiok, Katsuhito

    2015-03-01

    This study is a radiographic analysis. To compare the fusion rates after anterior cervical discectomy and fusion (ACDF) using x-rays versus computerized tomography (CT). Although fusion status may be obvious when evaluating ACDFs performed in the remote past, determining the presence of a solid fusion at earlier time points after ACDF is often ambiguous but a necessary part of practice. Commonly used tools include radiographs and CT scans. Currently, there is no gold standard imaging modality to determine fusion status. Twenty-two patients status post-ACDF (cortical allograft with anterior plates) at 34 levels with CT scans and dynamic x-rays obtained at 3, 6, and 12 months postoperatively were included. Four spine surgeons blinded to the time point independently determined fusion status according to the criteria. On the basis of the x-ray criteria, the fusion rates were 26%, 41%, and 65% at 3, 6, and 12 months, respectively, postoperatively. On the basis of CT criteria, the fusion rates were 79%, 79%, and 91% at 3, 6, and 12 months, respectively. There was a significant difference in the predicted fusion rate at each time point comparing x-ray versus CT criteria. In addition, at 3 months, 41% of the levels (11/27) thought to be fused by CT criteria demonstrated >1 mm motion on dynamic x-rays. At 6 months, 33% (9/27) of the levels thought to be fused by CT demonstrated persistent motion of ≥1 mm. At 12 months, 23% (7/31) of the levels considered fused by CT still had persistent motion. X-ray criteria for fusion, which incorporate both static and dynamic factors, predicted lower fusion rates at each time point when compared with CT scans, which evaluate only static factors. Depending on the time point, anywhere from 23% to 41% of levels thought to be fused by CT criteria demonstrated persistent motion on dynamic x-rays. Although fusion by itself, levels demonstrating >1 mm motion are less likely to be solidly fused. Thus, we conclude that CT scans may overestimate

  13. Eye lens radiation exposure and repeated head CT scans: A problem to keep in mind

    Energy Technology Data Exchange (ETDEWEB)

    Michel, Morgane; Jacob, Sophie [Institute for Radiological Protection and Nuclear Safety, IRSN/DRPH/SRBE/Laboratoire d' Epidemiologie, BP 17, 92 262 Fontenay-aux-Roses (France); Roger, Gilles [Otolaryngology Department, Trousseau Hospital, Paris (France); Pelosse, Beatrice [Ophthalmology Department, Trousseau Hospital, Paris (France); Laurier, Dominique [Institute for Radiological Protection and Nuclear Safety, IRSN/DRPH/SRBE/Laboratoire d' Epidemiologie, BP 17, 92 262 Fontenay-aux-Roses (France); Le Pointe, Hubert Ducou [Radiology Department, Trousseau Hospital, Paris (France); Bernier, Marie-Odile, E-mail: marie-odile.bernier@irsn.fr [Institute for Radiological Protection and Nuclear Safety, IRSN/DRPH/SRBE/Laboratoire d' Epidemiologie, BP 17, 92 262 Fontenay-aux-Roses (France)

    2012-08-15

    Objectives: The deterministic character of radiation-induced cataract is being called into question, raising the possibility of a risk in patients, especially children, exposed to ionizing radiation in case of repeated head CT-scans. This study aims to estimate the eye lens doses of a pediatric population exposed to repeated head CTs and to assess the feasibility of an epidemiological study. Methods: Children treated for a cholesteatoma, who had had at least one CT-scan of the middle ear before their tenth birthday, were included. Radiation exposure has been assessed from medical records and telephone interviews. Results: Out of the 39 subjects contacted, 32 accepted to participate. A total of 76 CT-scans were retrieved from medical records. At the time of the interview (mean age: 16 years), the mean number of CT per child was 3. Cumulative mean effective and eye lens doses were 1.7 mSv and 168 mGy, respectively. Conclusion: A relatively high lens radiation dose was observed in children exposed to repeated CT-scans. Due to that exposure and despite the difficulties met when trying to reach patients' families, a large scale epidemiological study should be performed in order to assess the risk of radiation-induced cataracts associated with repeated head CT.

  14. Answers to Common Questions About the Use and Safety of CT Scans.

    Science.gov (United States)

    McCollough, Cynthia H; Bushberg, Jerrold T; Fletcher, Joel G; Eckel, Laurence J

    2015-10-01

    Articles in the scientific literature and lay press over the past several years have implied that computed tomography (CT) may cause cancer and that physicians and patients must exercise caution in its use. Although there is broad agreement on the latter point--unnecessary medical tests of any type should always be avoided--there is considerable controversy surrounding the question of whether, or to what extent, CT scans can lead to future cancers. Although the doses used in CT are higher than those used in conventional radiographic examinations, they are still 10 to 100 times lower than the dose levels that have been reported to increase the risk of cancer. Despite the fact that at the low doses associated with a CT scan the risk either is too low to be convincingly demonstrated or does not exist, the magnitude of the concern among patients and some medical professionals that CT scans increase cancer risk remains unreasonably high. In this article, common questions about CT scanning and radiation are answered to provide physicians with accurate information on which to base their medical decisions and respond to patient questions. Copyright © 2015 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  15. Familial Cerebral Cavernous Malformations Are Associated with Adrenal Calcifications on CT Scans: An Imaging Biomarker for a Hereditary Cerebrovascular Condition.

    Science.gov (United States)

    Strickland, Corinne D; Eberhardt, Steven C; Bartlett, Mary R; Nelson, Jeffrey; Kim, Helen; Morrison, Leslie A; Hart, Blaine L

    2017-08-01

    Purpose To determine if adrenal calcifications seen at computed tomography (CT) are associated with familial cerebral cavernous malformations (fCCMs) in carriers of the CCM1 Common Hispanic Mutation. Materials and Methods This study was approved by the institutional review board. The authors retrospectively reviewed abdominal CT scans in 38 patients with fCCM, 38 unaffected age- and sex-matched control subjects, and 13 patients with sporadic, nonfamilial cerebral cavernous malformation (CCM). The size, number, and laterality of calcifications and the morphologic characteristics of the adrenal gland were recorded. Brain lesion count was recorded from brain magnetic resonance (MR) imaging in patients with fCCM. The prevalence of adrenal calcifications in patients with fCCM was compared with that in unaffected control subjects and those with sporadic CCM by using the Fisher exact test. Additional analyses were performed to determine whether age and brain lesion count were associated with adrenal findings in patients with fCCM. Results Small focal calcifications (SFCs) (≤5 mm) were seen in one or both adrenal glands in 19 of the 38 patients with fCCM (50%), compared with 0 of the 38 unaffected control subjects (P < .001) and 0 of the 13 subjects with sporadic CCM (P = .001). Adrenal calcifications in patients with fCCM were more frequently left sided, with 17 of 19 patients having more SFCs in the left adrenal gland than the right adrenal gland and 50 of the 61 observed SFCs (82%) found in the left adrenal gland. No subjects had SFCs on the right side only. In patients with fCCM, the presence of SFCs showed a positive correlation with age (P < .001) and number of brain lesions (P < .001). Conclusion Adrenal calcifications identified on CT scans are common in patients with fCCM and may be a clinically silent manifestation of disease. (©) RSNA, 2017.

  16. Automated midline shift and intracranial pressure estimation based on brain CT images.

    Science.gov (United States)

    Chen, Wenan; Belle, Ashwin; Cockrell, Charles; Ward, Kevin R; Najarian, Kayvan

    2013-04-13

    In this paper we present an automated system based mainly on the computed tomography (CT) images consisting of two main components: the midline shift estimation and intracranial pressure (ICP) pre-screening system. To estimate the midline shift, first an estimation of the ideal midline is performed based on the symmetry of the skull and anatomical features in the brain CT scan. Then, segmentation of the ventricles from the CT scan is performed and used as a guide for the identification of the actual midline through shape matching. These processes mimic the measuring process by physicians and have shown promising results in the evaluation. In the second component, more features are extracted related to ICP, such as the texture information, blood amount from CT scans and other recorded features, such as age, injury severity score to estimate the ICP are also incorporated. Machine learning techniques including feature selection and classification, such as Support Vector Machines (SVMs), are employed to build the prediction model using RapidMiner. The evaluation of the prediction shows potential usefulness of the model. The estimated ideal midline shift and predicted ICP levels may be used as a fast pre-screening step for physicians to make decisions, so as to recommend for or against invasive ICP monitoring.

  17. Semiautomatic brain morphometry from CT images

    Science.gov (United States)

    Soltanian-Zadeh, Hamid; Windham, Joe P.; Peck, Donald J.

    1994-05-01

    Fast, accurate, and reproducible volume estimation is vital to the diagnosis, treatment, and evaluation of many medical situations. We present the development and application of a semi-automatic method for estimating volumes of normal and abnormal brain tissues from computed tomography images. This method does not require manual drawing of the tissue boundaries. It is therefore expected to be faster and more reproducible than conventional methods. The steps of the new method are as follows. (1) The intracranial brain volume is segmented from the skull and background using thresholding and morphological operations. (2) The additive noise is suppressed (the image is restored) using a non-linear edge-preserving filter which preserves partial volume information on average. (3) The histogram of the resulting low-noise image is generated and the dominant peak is removed from it using a Gaussian model. (4) Minima and maxima of the resulting histogram are identified and using a minimum error criterion, the brain is segmented into the normal tissues (white matter and gray matter), cerebrospinal fluid, and lesions, if present. (5) Previous steps are repeated for each slice through the brain and the volume of each tissue type is estimated from the results. Details and significance of each step are explained. Experimental results using a simulation, a phantom, and selected clinical cases are presented.

  18. Trends in CT scan rates in children and pregnant women: teaching, private, public and nonprofit facilities

    Energy Technology Data Exchange (ETDEWEB)

    Hoshiko, Sumi; Smith, Daniel; Fan, Cathyn; Jones, Carrie R.; McNeel, Sandra V. [Environmental Health Investigations Branch, California Department of Public Health, Richmond, CA (United States); Cohen, Ronald A. [Children' s Hospital and Research Center Oakland, Department of Radiology, Oakland, CA (United States)

    2014-05-15

    Radiation exposure from medical sources now equals or exceeds that from natural background sources, largely attributable to a 20-fold increase in CT use since 1980. Increasing exposure to children and fetuses is of most concern due to their heightened susceptibility. More recently, CT use may be leveling or decreasing, but it is unclear whether this change is widespread or varies by type of institution. We sought to characterize trends in CT utilization in California hospitals and emergency departments among children and pregnant women, looking at different types of facilities, such as teaching, private, public and nonprofit institutions. We examined frequency of CT examinations by year from 229 facilities reporting CT usage in routinely collected California statewide data for 2005-2012. We modeled trends overall and by facility type. CT scans for pediatric and pregnant patient visits in the emergency department increased initially, then started to decline after 2008. Among hospital admissions, rates declined or leveled after 2005. In the emergency department, CT rates varied between types of facilities, with teaching hospitals reducing use sooner and more sharply than other types of facilities. CT utilization in California among children and pregnant women has begun to level or decline. Still, population exposure remains at historically high levels, warranting consideration of potential public health implications. Further examination of reasons for trends among hospital types, particularly how teaching hospitals have reduced rates of CT utilization, may help identify strategies for CT reduction without compromising patient care. (orig.)

  19. CT Perfusion in Acute Stroke: "Black Holes" on Time-to-Peak Image Maps Indicate Unsalvageable Brain.

    Science.gov (United States)

    Meagher, Ruairi; Shankar, Jai Jai Shiva

    2016-11-01

    CT perfusion is becoming important in acute stroke imaging to determine optimal patient-management strategies. The purpose of this study was to examine the predictive value of time-to-peak image maps and, specifically, a phenomenon coined a "black hole" for assessing infarcted brain tissue at the time of scan. Acute stroke patients were screened for the presence of black holes and their follow-up imaging (noncontrast CT or MR) was reviewed to assess for infarcted brain tissue. Of the 23 patients with signs of acute ischemia on CT perfusion, all had black holes. The black holes corresponded with areas of infarcted brain on follow-up imaging (specificity 100%). Black holes demonstrated significantly lower cerebral blood volumes (P Black holes on time-to-peak image maps represent areas of unsalvageable brain. Copyright © 2016 by the American Society of Neuroimaging.

  20. Pelvic artery calcification detection on CT scans using convolutional neural networks

    Science.gov (United States)

    Liu, Jiamin; Lu, Le; Yao, Jianhua; Bagheri, Mohammadhadi; Summers, Ronald M.

    2017-03-01

    Artery calcification is observed commonly in elderly patients, especially in patients with chronic kidney disease, and may affect coronary, carotid and peripheral arteries. Vascular calcification has been associated with many clinical outcomes. Manual identification of calcification in CT scans requires substantial expert interaction, which makes it time-consuming and infeasible for large-scale studies. Many works have been proposed for coronary artery calcification detection in cardiac CT scans. In these works, coronary artery extraction is commonly required for calcification detection. However, there are few works about abdominal or pelvic artery calcification detection. In this work, we present a method for automatic pelvic artery calcification detection on CT scan. This method uses the recent advanced faster region-based convolutional neural network (R-CNN) to directly identify artery calcification without a need for artery extraction since pelvic artery extraction itself is challenging. Our method first generates category-independent region proposals for each slice of the input CT scan using region proposal networks (RPN). Then, each region proposal is jointly classified and refined by softmax classifier and bounding box regressor. We applied the detection method to 500 images from 20 CT scans of patients for evaluation. The detection system achieved a 77.4% average precision and a 85% sensitivity at 1 false positive per image.

  1. Clinical utility of 18 Fluorodeoxyglucose (FDG-PET/CT scans in patients with suspect ocular tuberculosis

    Directory of Open Access Journals (Sweden)

    Salil Mehta

    2013-01-01

    Full Text Available Systemic imaging of patients with suspect ocular tuberculosis include chest X-rays and computed tomography (CT scans. Reports have suggested a role for 18 fluorodeoxyglucose-positron emission tomography/CT (FDG-PET/CT scans. We report on the clinical utility of 18 FDG PET/CT in two patients. Case 1: A 38-year-old female patient presented with recurrent anterior uveitis. A 18 FDG-PET scan revealed metabolically active supraclavicular and chest lymph nodes. An aspiration cytology of the cervical lymph node revealed caseating granulomas suggestive of tuberculosis. Case 2: A 58-year-old female patient presented with recurrent anterior uveitis. A 18 FDG-PET scan revealed metabolically active lymph nodes in the neck. A biopsy of the cervical lymph node revealed epithelioid granulomas suggestive of tuberculosis. Both patients were started on standard antitubercular therapy with a subsequent marked reduction of activity. PET/CT scans may suggest the sites of safe high-yield biopsies.

  2. Isometric Tunnel Placement in Ulnar Collateral Ligament Reconstruction with Single CT Scan

    Directory of Open Access Journals (Sweden)

    Erica Kholinne

    2017-01-01

    Full Text Available Background. Isometric tunnel placement for anterior bundle of the medial collateral ligament (MCL reconstruction is mandatory for successful surgery. Purpose. This study aimed to demonstrate a useful method for identifying isometric tunnel placement using a single computed tomography (CT scan. Study Design. Descriptive Laboratory Study. Methods. Five normal elbows were scanned at 4 different flexion angles at 45° increment. Three-dimensional models were analyzed using 2 different approaches: single and multiple CT scans methods. Ligament footprints in the humerus and the ulna were registered. Ligament length and isometric points were defined. The locations of the isometric points were imported into both methods to be compared. Results. There was no significant difference between 2 methods in calculating the length in every zone. There was also no significant difference in determining isometric ligament’s origin point, which is located approximately 18.2±4.0 mm and 18.4±2.9 mm for single and multiple CT, respectively, measured inferolaterally from medial epicondyle. Conclusions. A solid preoperative plan is critical when predicting tunnel locations due to the difficulty in finding isometric points and the individuality of optimal bone tunnel locations. Using single CT scan, optimal locations can be predicted with the same accuracy as a multiple CT scans with less radiation exposure.

  3. Role of 18F-FDG PET/CT vs CT-scan in patients with pulmonary metastases previously operated on for colorectal liver metastases.

    Science.gov (United States)

    Lopez-Lopez, Victor; Robles, Ricardo; Brusadin, Roberto; López Conesa, Asuncion; Torres, Juan; Perez Flores, Domingo; Navarro, Jose Luis; Gil, Pedro Jose; Parrilla, Pascual

    2018-01-01

    There is currently no conclusive scientific evidence available regarding the role of the 18F-FDG PET/CT for detecting pulmonary metastases from colorectal cancer (PMCRC) in patients operated on for colorectal liver metastases (CRLM). In the follow up of patients who underwent surgery for CRLM, we compare CT-scan and 18F-FDG PET/CT in patients with PMCRC. We designed the study prospectively performing an 18F-FDG PET/CT on all patients operated on for CRLM where the CT-scan detected PMCRC during the follow up. We included patients who were operated on for PMCRC because the histological findings were taken as a control rather than biopsies. Of the 101 pulmonary nodules removed from 57 patients, the CT-scan identified a greater number (89 nodules) than the 18F-FDG PET/CT (75 nodules) (p CT-scan (90 vs 76%, respectively) with a lower specificity (50 vs 75%, respectively) than with the 18F-FDG PET/CT. There were no differences between positive-predictive value and negative-predictive value. The 18F-FDG PET/CT detected more pulmonary nodules in four patients (one PMCRC in each of these patients) and more extrapulmonary disease in six patients (four mediastinal lymph nodes, one retroperitoneal lymph node and one liver metastases) that the CT-scan had not detected. Although CT-scans have a greater capacity to detect PMCRC, the 18F-FDG PET/CT could be useful in the detection of more pulmonary and extrapulmonary disease not identified by the CT-scan. Advances in knowledge: We tried to clarify the utility of 18F-FDG PET/CT in the management of this subpopulation of patients.

  4. Scoring system for CT scan findings of ovarian cystic lesions

    Energy Technology Data Exchange (ETDEWEB)

    Hattori, Kaoru

    1987-09-01

    It is important to preoperatively establish a diagnosis of a gynecologic pelvic mass. A group of 137 female patients with suspected pelvic cystic lesions were studied by computerized tomography (CT). Histologically, 22 patients were proved to have ovarian cystadenocarcinoma and 115 patients a benign cystic mass, i.e. cystadenoma, lutein cyst, endometrial cyst, retentional cyst and paraovarian cyst. A scoring system was made to obtain higher accuracy in CT evaluation of ovarian cystic lesions. It includes seven factors, (1) volume, (2) solid component protruding from the wall, (3) thickness of the wall, (4) focal thickening of the wall, (5) loculation, (6) attenuation number of the tumor and (7) nonhomogenousess of the tumor. Using this scoring system, a correct differential diagnosis was made in all cases except 7, 4 uterine fibroids with remarkable degenaration, a large endometrial cyst with a high attenuation number, a dermoid cyst with an irregular pattern and a mucinous cystadenoma with benign solid component. The accuracy of diagnosis was 100 % in malignant masses and 93.9 % in benign masses. This scoring system was shown to have clinical significance for the differential diagnosis of a pelvic cystic lesions.

  5. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... traditional x-rays, particularly of soft tissues and blood vessels. CT scanning provides more detailed information on head injuries, stroke , brain tumors and other brain diseases than regular radiographs (x-rays). top of page ...

  6. Feasibility of iodine contrast enhanced CT-scan during a 18F-fluorodeoxyglucose Positron Emission Tomography

    Science.gov (United States)

    Houzard, C.; Tychyj, C.; Morelec, I.; Ricard, F.; Got, P.; Cotton, F.; Giammarile, F.; Maintas, D.

    2009-06-01

    OBJECTIVE: this prospective study evaluates the feasibility in current clinical practice of contrast enhanced CT-scan for diagnosis purpose, performed during 18FDG PET-CT study with a PET/CT tomography. METHOD: 25 patients underwent FDG imaging for lymphoma staging. The PET scan was done immediately after the usual low dose CT (lCT). A second CT scan was consequently acquired, by using classical diagnosis CT parameters (dCT) and iodinated contrast. For each patient, all CT attenuation correction (CTAC) PET images were visually compared. Density in Hounsfield units (HU) and maximum Standardized Uptake Value (SUVmax) were then measured on different organs and up to 5 specific lymphoma localizations (total of 294 measurements). RESULTS: Visual analysis was similar for the 2 modalities, without discordant interpretation for the pathologic sites. SUVmax means and standard deviation of each organ for lCTAC and dCTAC were comparable. The equation of the fitted multiple linear regression model was: dCT=0.0748191 + 1.17024*lCT (98.71%; p < 0.01). CONCLUSION: These first results allow the use of injected CT scan, before the PET scan acquisition for lymphoma staging with this PET-CT scan, not affected by the height atomic number and elevated density. A great benefit is therefore obtained on diagnostic, logistic and radioprotection purposes.

  7. Dose profile study in head CT scans using a male anthropomorphic phantom

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, Alvaro M.L.; Santana, Priscila do C.; Mourao, Arnaldo P., E-mail: amlgphys@gmail.com, E-mail: pridili@gmail.com, E-mail: apratabhz@gmail.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte (Brazil). Departamento de Engenharia Nuclear; Centro Federal de Educação Tecnológica de Minas Gerais (CEFET-MG), Belo Horizonte, MG (Brazil)

    2017-11-01

    Computed tomography (CT) test is an efficient and non-invasive method to obtain data about internal structures of the human body. CT scans contribute with the highest absorbed doses in population due X-ray beam attenuation and it has raised concern in radiosensitive tissues. Techniques for the optimization of CT scanning protocols in diagnostic services have been developing with the objective of decreasing the absorbed dose in the patient, aiming image quality within acceptable parameters for diagnosis by noise control. Routine head scans were performed using GE CT scan of 64 channels programmed with automatic exposure control and voltages of 80, 100 and 120 kV attaching the noise index in approximately 0.5%, using the tool of smart mA. An anthropomorphic adult male phantom was used and radiochromic film strips were placed to measure the absorbed dose deposited in areas such as the lens, thyroid and pituitary for study of dose deposited in these important areas containing high radiosensitive tissues. Different head scans were performed using optimized values of mA.s for the different voltages. The absorbed dose measured by the film strips were in the range of the 0.58 and 44.36 mGy. The analysis of noise in the images is within the acceptable levels for diagnosis, and the optimized protocol happens with the voltage of 100 kV. The use of other voltage values can allow obtain better protocols for head scans. (author)

  8. CT, MRI and ultrasound scanning rates: evaluation of cancer diagnosis, staging and surveillance in Ontario.

    Science.gov (United States)

    Coburn, Natalie; Przybysz, Raymond; Barbera, Lisa; Hodgson, David; Sharir, Sharon; Laupacis, Andreas; Law, Calvin

    2008-12-01

    To examine practice patterns and rates of computed tomography (CT), magnetic resonance imaging (MRI), and abdominal ultrasound (AUS) during staging, treatment and surveillance for cancer patients. Using Ontario Health Insurance Plan billing data linked to the Ontario Cancer Registry, we determined rates of CT, MRI, and AUS by body site for breast, colorectal, lung, lymphoma, and prostate cancer, from 1998 to 2002. Rates of scans were additionally examined by region of patient residence and time from cancer diagnosis. The frequency of imaging increased in nearly all scans and tumors over the study period. Rates of peri-diagnosis scans varied substantially by region, ranging from 1.7-fold variation (CT for lung cancer) to 50-fold variation (MRI for breast cancer). For breast cancer, there is possible over-utilization of CT, but overall rates of scanning appear reasonable for the other four cancers. Considerable regional variation in imaging rates suggests utilization guidelines should be developed or knowledge transfer initiatives are needed to improve compliance to existing guidelines. In breast cancer, there appears to be over-utilization of imaging. Further studies are necessary to determine utilization for each stage, the reason scans were obtained, and the impact of scans on patient outcomes. (c) 2008 Wiley-Liss, Inc.

  9. Gyral high density on CT scan after head injury; [sup 123]I-IMP SPECT and MRI findings in three children

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Takumi; Matsumoto, Kiyoshi (Showa Univ., Tokyo (Japan). School of Medicine); Sakamoto, Tetsuya; Aruga, Tohru

    1994-02-01

    The authors treated three children who had 'gyral high density' on plain CT scans after head injury with acute subdural hematoma. [sup 123]I-IMP SPECT (IMP) and MRI in the chronic stage were performed. All were males, about one year of age, with acute subdural hematoma. CT scan 48 hours after injury showed diffuse low density in the ipsilateral parenchyma with minimum midline shift, and IMP showed decreased activity in the same area. Plain CT scan 1 to 3 weeks after injury showed remarkably high density along the gyri in part of the same area. This area was markedly enhanced on CT with contrast medium and showed decreased blood flow on IMP. This high density area disappeared within 2 months after injury and the area concerned showed brain atrophy. In the chronic stage (after 6 months), only the high density area along the gyri seen in the CT scan showed MRI evidence of ishemia, but there was no definite evidence of hemorrhage. All three children had hemiplegia at the time of discharge. The gyral high density suggests ischemic brain, but the pathophysiological process might be different from that of so-called hemorrhagic infarction. Presumably, it is due to incomplete autoregulation, the incomplete blood-brain barrier and the sensitivity to stimulation of cerebral blood vessels in the brains of infants. The intensity and range of the gyral high density are considered to be important in estimating the future amount of atrophic change in the insulted brain and the resulting sequelae. (author).

  10. CCD-based optical CT scanning of highly attenuating phantoms

    Energy Technology Data Exchange (ETDEWEB)

    Al-Nowais, Shamsa [Department of Physics, University of Surrey, Guildford (United Kingdom); Doran, Simon J [CRUK Clinical MR Research Group, Institute of Cancer Research, Sutton (United Kingdom)], E-mail: Simon.Doran@icr.ac.uk

    2009-05-01

    The introduction of optical computed tomography (optical-CT) offers economic and easy to use 3-D optical readout for gel dosimeters. However, previous authors have noted some challenges regarding the accuracy of such imaging techniques at high values of optical density. In this paper, we take a closer look at the 'cupping' artefact evident in both light-scattering polymer systems and highly light absorbing phantoms using our CCD-based optical scanner. In addition, a technique is implemented whereby the maximum measurable optical absorbance is extended to correct for any errors that may have occurred in the estimated value of the dark current or ambient light reaching the detector. The results indicate that for absorbance values up to 2.0, the optical scanner results have good accuracy, whereas this is not the case at high absorbance values for reasons yet to be explained.

  11. The diagnostic value of PET/CT scanning in patients with cervical cancer

    DEFF Research Database (Denmark)

    Loft, Annika; Berthelsen, Anne Kiil; Roed, Henrik

    2007-01-01

    OBJECTIVE: To investigate the clinical value of PET/CT as a supplement to FIGO staging in patients with cervical cancer stage >or=1B. METHODS: This prospective study included 120 consecutive patients. After staging, a whole-body PET/CT scan was performed and these examinations were divided into two......%, negative predictive value (NPV) 96%, sensitivity 75%, specificity 96%. Regarding para-aortal nodal disease in the total population of 119 patients, 15 patients had true positive scans. The number of true negatives was 103, resulting in PPV 94%, NPV 100%, sensitivity 100% and specificity 99%. PET/CT scans...... groups: (1) patients suitable for radical hysterectomy including lymph node dissection and (2) patients referred to combined chemo/radiation therapy. The results were compared to histopathological findings and/ or follow-up. RESULTS: Twenty-seven patients underwent radical surgery; four of these had PET...

  12. Wallerian degeneration of brain: MRI and CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Woo Suk; Ryu, Kyung Nam [Kyung Hee University Hsopital, Seoul (Korea, Republic of)

    1992-11-15

    Wallerian degeneration is well known as the anterograde degeneration of axon and their accompanying myelin sheath from injury to the proximal portion of the axon or its cell body. The most common cause of wallerian degeneration is cerebral infarction. Authors experienced three patients with old hemispheric infarct with typical wallerian degeneration in the brain stem, which was demonstrated by magnetic resonance imaging (MRI) in two cases and CT in one case. This report demonstrates the wallerian degeneration in the corticospinal tract in on the MRI and CT with the brief review of literatures.

  13. Overbeaming and overlapping of volume-scan CT with tube current modulation in a 320-detector row CT scanner

    Science.gov (United States)

    Liao, Ying-Lan; Chen, Yan-Shi; Lai, Nan-Ku; Chuang, Keh-Shih; Tsai, Hui-Yu

    2014-11-01

    The purpose of this study was to evaluate the performance of volume scan tube current modulation (VS-ATCM) with adaptive iterative dose reduction 3D (AIDR3D) technique in abdomen CT examinations. We scanned an elliptical cone-shaped phantom utilizing AIDR3D technique combined with VS-ATCM mode in a 320-detector row CT scanner. The image noise distributions with conventional filtered back-projction (FBP) technique and those with AIDR3D technique were compared. The radiation dose profile and tube current time product (mAs) in three noise levels of VS-ATCM modes were compared. The radiation beam profiles of five preset scan lengths were measured using Gafchromic film strips to assess the effects of overbeaming and everlapping. The results indicated that the image noises with AIDR3D technique was 13-74% lower than those in FBP technique. The mAs distributions can be a prediction for various abdominal sizes when undergoing a VS-ATCM mode scan. Patients can receive the radiation dose of overbeaming and overlapping during the VS-ATCM mode scans.

  14. Endoscopic Management of Inverted Papilloma Using CT Scan as the Predictor of Tumour Origin

    Directory of Open Access Journals (Sweden)

    Ravi Roy

    2017-08-01

    Full Text Available Introduction Inverted papillomas are notorious for recurrence. The surgical cause attributed to recurrence is failure to achieve good surgical exposure and inadequate clearance of disease. Pre-operative prediction about the site of origin by CT Scan may contribute to a better surgical outcome. This study was undertaken to assess if focal hyperostosis on pre-operative CT scan can be considered to be a predictor of the site of tumour origin and correlate with endoscopic finding of the site of origin. Materials and Method  A prospective descriptive study was carried out between Jan 2014 and May 2016. Fifteen patients of histopathologically proven inverted papilloma that reported during this time period were evaluated using contrast enhanced CT Scan and subsequently underwent endoscopic excision of tumour identifying the tumour origin. Assessment of age, gender, symptoms, pre-operative staging, location of the tumour origin on CT Scan and surgical correlation of origin was done. Post-operative follow-up was done at 1 month, 3 months and 6 monthly thereafter. Results Six (40% were classified as Krouse II and nine (60% were classified as Krouse III. 12 (80% arising from maxillary sinus, 02 (13.3% arising from maxillary sinus and anterior ethmoids and 01 (6.7% from sphenoid. Thirteen (86.7% cases CT scan could predict the tumour origin which was confirmed during surgery. All cases managed by endoscopic technique with no recurrence or co-existence of malignancy. Discussion Focal hyperostosis in the walls of paranasal sinus is seen to be associated with IP tumour origin, the cause of which is not fully understood. It is hypothesized that tumour induced inflammation at the site of origin leads to bone remodeling and increased bone deposition with vascularity at the site of attachment. Conclusion CT scan is a good predictor of tumour origin and a conservative endoscopic approach can be planned accordingly for complete clearance of disease.

  15. Periprosthetic osteolysis after AES total ankle replacement: Conventional radiography versus CT-scan.

    Science.gov (United States)

    Viste, Anthony; Al Zahrani, Nader; Brito, Nuno; Lienhart, Christophe; Fessy, Michel Henri; Besse, Jean-Luc

    2015-09-01

    The aim of this study was to compare conventional X-rays and CT-scan in detecting peri-prosthetic osteolytic lesions, a major concern after total ankle replacement (TAR). We prospectively assessed 50 patients (mean age 56 years), consecutively operated on by the same senior surgeon, between 2003 and 2006 and with a mean follow-up period of 4 years (range, 2-6.2). The component used was AES total ankle replacement. The etiologies for total ankle arthroplasty were: posttraumatic in 50%, osteoarthritis secondary to instability in 36%. Plain radiographs were analyzed by 4 independent observers, using a 10-zone protocol (location) and 5 size categories. At 4-year follow-up, all patients had been CT-scan assessed with the same protocol by 2 independent observers. Plain radiographs showed dramatic progression of severe periprosthetic lyses (>10mm): from 14% to 36% of interface cysts for the tibial component respectively at 2 and 4-year follow-up and from 4% to 30% for the talar implant. The talar component was more accurately assessed by CT-scan (mean frontal and sagittal talar lesion: from 270 mm2 to 288 mm2 for CT-scan versus 133 mm2 to 174 mm2 for X-rays). For tibial cysts, axial views showed larger lesions (313 mm2 than frontal (194 mm2) or sagittal (213.5 mm2) views. At 4-year follow-up, 24% of patients had revision with curetage or arthrodesis, and at 7 years follow-up 38% were revised. These results are similar to recent AES series, justifying withdrawal of this device. CT-scan was more accurate than X-rays for detecting and quantifying periprosthetic osteolysis. We recommend a yearly radiological control and CT-scan in case of lesion on X-rays. Copyright © 2014 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  16. Brain mapping with single photon emission CT.

    Science.gov (United States)

    Matthew, E; Hill, T C

    1998-02-01

    To investigate the feasibility of performing brain mapping studies by using cortical activation paradigms and single photon emission computed tomography (SPECT) and to evaluate methods of analysis. Twenty healthy volunteers underwent technetium-99m bicisate SPECT under baseline conditions and during either full-field or right hemifield visual stimulation with a black and white reversing checkerboard pattern. Changes in regional cerebral perfusion were measured by using regions of interest (ROIs) and statistical parametric mapping. ROI analysis identified statistically significant increases in perfusion in the occipital cortex with full-field visual stimulation (mean +/- standard error of the mean percentage change from baseline: left, 8.0 +/- 1.5; right, 6.6 +/- 2.4). With right hemifield visual stimulation, perfusion was significantly increased only in the left occipital cortex (left, 5.2 +/- 1.5; right, -0.2 +/- 1.9). Statistical parametric mapping showed areas of activation (more than 100 voxel clusters showed significant change from baseline at a threshold value of P or = 2.58) in the left primary visual cortex (right hemifield visual stimulation) and in both right and left primary visual areas (full-field visual stimulation). Brain mapping studies were preformed with Tc-99m bicisate SPECT, and activation-induced changes were visualized and measured. These methods can be applied to develop improved methods of diagnosis and assessment of treatment outcome in patients with neuropsychiatric disorders.

  17. 3D quantification of soil structure and functioning based on PET and CT scanning techniques

    DEFF Research Database (Denmark)

    Garbout, Amin

    This thesis explores the potential of PET and CT scanning techniques to quantify and visualize soil structure, root development, and soil/plant interactions. At the investigated scale, these non-invasive and nondestructive techniques have some obvious advantages compared with most other techniques....... The processed measurements show some expected and a few unexpected effects (or lack of effects) on different characteristics of soil structure. The combination of CT and PET scanning in an air plant soil controller system revealed some very interesting research possibilities. Interactions between soil structure...

  18. Extracranial tumor vascularity: determination by dynamic CT scanning. Part 1. Concepts and signature curves

    Energy Technology Data Exchange (ETDEWEB)

    Som, P.M.; Lanzieri, C.F.; Sacher, M.; Lawson, W.; Biller, H.F.

    1985-02-01

    Combined conventional drip infusion-dynamic CT scanning was performed on 28 patients with clinically discovered neck or parapharyngeal space masses. Seventeen of these also had digital venous study or angiographic studies either to confirm the CT diagnosis or as part of an embolization procedure. The studies indicate that the initial portion of the dynamic scan curve can be characteristically classified as either an arterial, venous, or hypovascular signature curve. The current ideas of how these curves are generated, the specific appearance of these signature curves, and the types of pathologic conditions that correlate with each curve are discussed.

  19. A vast increase in the use of CT scans for investigating occult hip fractures

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Robert, E-mail: Robert.jordan@doctors.org.uk; Dickenson, Edward, E-mail: edwarddickenson@doctors.org.uk; Westacott, Daniel, E-mail: dan_westacott@hotmail.com; Baraza, Njalalle, E-mail: njaleb@Doctors.Org.Uk; Srinivasan, Kuntrapka, E-mail: bijusri@Yahoo.Co.Uk

    2013-08-15

    Background: Early diagnosis in neck of femur fractures has been shown to improve outcome. The National Institute for Clinical Excellence recommends if an occult hip fracture is suspected then an MRI should be performed and if not available within 24 h a CT should be considered. At our centre, emergency MRI is rarely available and so CT is commonly used. Objectives: Our study aims to analyse the trends in CT use over a five year period for the diagnosis of neck of femur fractures. Methods: Both the number of patients with a hip fracture and those undergoing a CT hip to diagnose an occult injury were identified across two district general hospitals between 2006–2007 and 2010–2011. The time from initial radiograph to CT and initial radiograph to operation were calculated. Results: In 2006–2007, of 547 hip fractures, 20 CT hips were performed and 6 reported as a fractured neck of femur (30%). In 2010–2011, of 499 hip fractures, 239 CT hips were performed and 65 fractures were recognised (27%). The mean time from radiograph until CT scan was 2.0 days in 2007 and 3.2 days in 2011, which was a statistically significant difference (p < 0.001). For those diagnosed using a CT scan the mean time from admission X-ray to surgery was 1.2 days in 2007 and 3.6 days in 2011. Conclusion: Clinicians are becoming increasingly reliant on CT for the diagnosis of hip fractures with our data suggesting further imaging is one factor that can delay time to diagnosis and theatre.

  20. CT scan findings of fungal pneumonia; Diagnose der Pilzpneumonie in der Thorax-CT

    Energy Technology Data Exchange (ETDEWEB)

    Heckmann, M.; Uder, M.; Bautz, W.; Heinrich, M. [Erlangen-Nuernberg Univ., Erlangen (Germany). Inst. fuer Diagnostische Radiologie

    2008-07-01

    The importance of fungal infection of the lung in immunocompromised patients has increased substantially during the last decades. Numerically the most patients are those with neutropenia, e.g. patients with malignancies or solid organ and stem cell transplantation, chemotherapy, corticosteroid use and HIV infection. Although fungal infections can occur in immunocompetent patients, their frequency in this population is rare. The clinical symptoms such as fever accompanied with non-productive cough are unspecific. In some patients progression to hypoxemia and dyspnea may occur rapidly. In spite of improved antifungal therapy morbidity and mortality of these infections are still high. Therefore an early and non-invasive diagnosis is very important. That is why CT and even better High-Resolution-CT (HR-CT) is a very important modality in examining immunocompromised patients with a probability of fungal infection. CT is everywhere available and, as a non-invasive method, able to give the relevant diagnose efficiently. This paper should give an overview about the radiologic findings and possible differential diagnosis of diverse pulmonary fungal infections in CT. Pneumonias caused by Aspergillus, Cryptococcus, Candida, Histoplasma, Mucor and Geotrichum capitatum are illustrated. (orig.)

  1. SPEECH AND LANGUAGE DISORDERS IN PATIENTS WITH CVA COMPARISON WITH CT SCAN

    Directory of Open Access Journals (Sweden)

    A CHIT SAZ

    2001-09-01

    Full Text Available Introduction. Stroke is a sudden onset of neurologic signs as a result of the ischemic or intracranial hemmorhage because of the cerebrovascular disease that stands for at least 24 hours. Cerebrovascular disease is one of the most important factors that causes speech disorder. The aim of this study is to show the characteristics of speech and language related to the various parts of the brain lesion. Methods. In this study 64 patients with CVA and speech disorders were tested. Lesions in 36 patients were ischemic, 17 patients were hemmorhagic. 11 patients had no any significant lesion on CT-scan. The test unndertaken included "Farsi Aphasia Test" written by Dr. Nilipoor. Results. Fifty percent of patients were in 61-70 years old group. 70.3 percent were male and 29.7 percent were female. In aspect of the hemisphere involved 50 percent were left hemisphere and 28.1 percent Right hemisphere and 4.7 percent with both hemisphers involvement. Discussion. In CVA patient with speech disorders the temporal lobe of the left hemisphere is mostly involved, and in respect to oral speech disorders in CVA, most of the problems were seen in non verbal fluency and the least problems were seen in repetition.

  2. Brain dead or not? CT angiogram yielding false-negative result on brain death confirmation.

    Science.gov (United States)

    Johnston, Robyn; Kaliaperumal, Chandrasekaran; Wyse, Gerald; Kaar, George

    2013-01-08

    We describe a case of severe traumatic brain injury with multiple facial and skull fractures where CT angiogram (CTA) failed to yield a definite result of brain death as an ancillary test. A 28-year-old man was admitted following a road traffic accident with a Glasgow Coma Score (GCS) of 3/15 and fixed pupils. CT brain revealed uncal herniation and diffuse cerebral oedema with associated multiple facial and skull fractures. 72 h later, his clinical condition remained the same with high intracranial pressure refractory to medical management. Clinical confirmation on brain death was not feasible owing to facial injuries. A CTA, performed to determine brain perfusion, yielded a 'false-negative' result. Skull fractures have possibly led to venous prominence in the cortical and deep venous drainage system. This point needs to be borne in mind while considering CTA as an ancillary test to confirm brain death.

  3. Normalization of CT scans reconstructed with different kernels to reduce variability in emphysema measurements

    Science.gov (United States)

    Gallardo Estrella, L.; van Ginneken, B.; van Rikxoort, E. M.

    2013-03-01

    Chronic Obstructive Pulmonary Disease (COPD) is a lung disease characterized by progressive air flow limitation caused by emphysema and chronic bronchitis. Emphysema is quantified from chest computed tomography (CT) scans as the percentage of attentuation values below a fixed threshold. The emphysema quantification varies substantially between scans reconstructed with different kernels, limiting the possibilities to compare emphysema quantifications obtained from scans with different reconstruction parameters. In this paper we propose a method to normalize scans reconstructed with different kernels to have the same characteristics as scans reconstructed with a reference kernel and investigate if this normalization reduces the variability in emphysema quantification. The proposed normalization splits a CT scan into different frequency bands based on hierarchical unsharp masking. Normalization is performed by changing the energy in each frequency band to the average energy in each band in the reference kernel. A database of 15 subjects with COPD was constructed for this study. All subjects were scanned at total lung capacity and the scans were reconstructed with four different reconstruction kernels. The normalization was applied to all scans. Emphysema quantification was performed before and after normalization. It is shown that the emphysema score varies substantially before normalization but the variation diminishes after normalization.

  4. The Profile of Head CT Scan Findings in Patients at Sebha Medical ...

    African Journals Online (AJOL)

    The collected data were analyzed using SPSS program (version 20). ... Sixty eight percent of the cases had normal scans. ... intraventricular hemorrhage, subdural hematoma, skull fracture, brain edema, hydrocephalus, intracranial masses.

  5. Incidental detection of colorectal lesions by FDG PET/CT scans in melanoma patients.

    Science.gov (United States)

    Young, Christopher J; Zahid, Assad; Choy, Ian; Thompson, John F; Saw, Robyn P M

    2017-11-01

    Increased use of PET/CT scans in oncology patients has raised detection of Colorectal incidentalomas (CIs). The frequency and diagnostic outcomes of identifying these lesions in melanoma patients have not previously been studied. This studies primary objective was to determine the prevalence of CIs found on PET/CT scans in melanoma patients. The secondary objectives were to correlate the PET/CT findings with the pathology found at colonoscopy, and identify which patients were referred for colonoscopy. A retrospective analysis of patients identified from the prospectively collected research database of Melanoma Institute Australia. 2509 patients with melanoma underwent PET/CT scans between 2001 and 2013. The prevalence of CIs, the correlation of lesions, and the survival of patients who underwent colonoscopy versus patients who did not were analyzed. The prevalence of CIs in melanoma patients who had PET/CT scans was 3.2%. Forty-five of the 81 (56%) patients with CIs underwent colonoscopy. Of these, premalignant or malignant disease was found in 58%. Patients with previous metastatic melanoma were significantly less likely to be referred for colonoscopy. Patients undergoing colonoscopy had significantly better survival, as did those without previous distant metastases before the CIs were found, and those without any metastases at the time the CIs were found. These factors were not significant on multivariate analysis. The prevalence of incidental colorectal lesions identified on PET/CT scans in melanoma patients was found to be equivalent to that in the general cancer population. Patients undergoing colonoscopy had better survival than those who did not. Copyright © 2017 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

  6. Interactive lung segmentation in abnormal human and animal chest CT scans

    Energy Technology Data Exchange (ETDEWEB)

    Kockelkorn, Thessa T. J. P., E-mail: thessa@isi.uu.nl; Viergever, Max A. [Image Sciences Institute, University Medical Center Utrecht, 3584 CX Utrecht (Netherlands); Schaefer-Prokop, Cornelia M. [Department of Radiology, Meander Medical Centre, 3813 TZ Amersfoort, The Netherlands and Diagnostic Image Analysis Group, Radboud University Nijmegen Medical Centre, 6525 GA Nijmegen (Netherlands); Bozovic, Gracijela [Center for Diagnostic Imaging and Physiology, Skåne University Hospital, Lund University, SE-221 85 Lund (Sweden); Muñoz-Barrutia, Arrate [Cancer Imaging Laboratory, Center for Applied Medical Research, University of Navarra, ES-31008 Pamplona, Navarra (Spain); Rikxoort, Eva M. van [Diagnostic Image Analysis Group, Radboud University Nijmegen Medical Centre, 6525 GA Nijmegen (Netherlands); Brown, Matthew S. [Center for Computer Vision and Imaging Biomarkers, Department of Radiological Sciences, David Geffen School of Medicine at UCLA, University of California, Los Angeles, California 90024 (United States); Jong, Pim A. de [Department of Radiology, University Medical Center Utrecht, 3584 CX Utrecht (Netherlands); Ginneken, Bram van [Diagnostic Image Analysis Group, Radboud University Nijmegen Medical Centre, 6525 GA Nijmegen (Netherlands); Image Sciences Institute, University Medical Center Utrecht, 3584 CX Utrecht (Netherlands)

    2014-08-15

    Purpose: Many medical image analysis systems require segmentation of the structures of interest as a first step. For scans with gross pathology, automatic segmentation methods may fail. The authors’ aim is to develop a versatile, fast, and reliable interactive system to segment anatomical structures. In this study, this system was used for segmenting lungs in challenging thoracic computed tomography (CT) scans. Methods: In volumetric thoracic CT scans, the chest is segmented and divided into 3D volumes of interest (VOIs), containing voxels with similar densities. These VOIs are automatically labeled as either lung tissue or nonlung tissue. The automatic labeling results can be corrected using an interactive or a supervised interactive approach. When using the supervised interactive system, the user is shown the classification results per slice, whereupon he/she can adjust incorrect labels. The system is retrained continuously, taking the corrections and approvals of the user into account. In this way, the system learns to make a better distinction between lung tissue and nonlung tissue. When using the interactive framework without supervised learning, the user corrects all incorrectly labeled VOIs manually. Both interactive segmentation tools were tested on 32 volumetric CT scans of pigs, mice and humans, containing pulmonary abnormalities. Results: On average, supervised interactive lung segmentation took under 9 min of user interaction. Algorithm computing time was 2 min on average, but can easily be reduced. On average, 2.0% of all VOIs in a scan had to be relabeled. Lung segmentation using the interactive segmentation method took on average 13 min and involved relabeling 3.0% of all VOIs on average. The resulting segmentations correspond well to manual delineations of eight axial slices per scan, with an average Dice similarity coefficient of 0.933. Conclusions: The authors have developed two fast and reliable methods for interactive lung segmentation in

  7. Interactive lung segmentation in abnormal human and animal chest CT scans.

    Science.gov (United States)

    Kockelkorn, Thessa T J P; Schaefer-Prokop, Cornelia M; Bozovic, Gracijela; Muñoz-Barrutia, Arrate; van Rikxoort, Eva M; Brown, Matthew S; de Jong, Pim A; Viergever, Max A; van Ginneken, Bram

    2014-08-01

    Many medical image analysis systems require segmentation of the structures of interest as a first step. For scans with gross pathology, automatic segmentation methods may fail. The authors' aim is to develop a versatile, fast, and reliable interactive system to segment anatomical structures. In this study, this system was used for segmenting lungs in challenging thoracic computed tomography (CT) scans. In volumetric thoracic CT scans, the chest is segmented and divided into 3D volumes of interest (VOIs), containing voxels with similar densities. These VOIs are automatically labeled as either lung tissue or nonlung tissue. The automatic labeling results can be corrected using an interactive or a supervised interactive approach. When using the supervised interactive system, the user is shown the classification results per slice, whereupon he/she can adjust incorrect labels. The system is retrained continuously, taking the corrections and approvals of the user into account. In this way, the system learns to make a better distinction between lung tissue and nonlung tissue. When using the interactive framework without supervised learning, the user corrects all incorrectly labeled VOIs manually. Both interactive segmentation tools were tested on 32 volumetric CT scans of pigs, mice and humans, containing pulmonary abnormalities. On average, supervised interactive lung segmentation took under 9 min of user interaction. Algorithm computing time was 2 min on average, but can easily be reduced. On average, 2.0% of all VOIs in a scan had to be relabeled. Lung segmentation using the interactive segmentation method took on average 13 min and involved relabeling 3.0% of all VOIs on average. The resulting segmentations correspond well to manual delineations of eight axial slices per scan, with an average Dice similarity coefficient of 0.933. The authors have developed two fast and reliable methods for interactive lung segmentation in challenging chest CT images. Both systems do

  8. Results of (68)Gallium-DOTATATE PET/CT Scanning in Patients with Multiple Endocrine Neoplasia Type 1.

    Science.gov (United States)

    Sadowski, Samira M; Millo, Corina; Cottle-Delisle, Candice; Merkel, Roxanne; Yang, Lily A; Herscovitch, Peter; Pacak, Karel; Simonds, William F; Marx, Stephen J; Kebebew, Electron

    2015-08-01

    Screening for neuroendocrine tumors (NETs) in patients with multiple endocrine neoplasia type 1 (MEN1) is recommended to detect primary and metastatic tumors, which can result in significant morbidity and mortality. The utility of somatostatin receptor imaging (68)Gallium-DOTATATE PET/CT in patients with MEN1 is not known. The aim of this study was to prospectively determine the accuracy of (68)Gallium-DOTATATE PET/CT vs (111)In- pentetreotide single-photon emission CT (SPECT)/CT and anatomic imaging in patients with MEN1. We performed a prospective study comparing (68)Gallium-DOTATATE PET/CT, (111)In-pentetreotide SPECT/CT, and triphasic CT scan to clinical, biochemical, and pathologic data in 26 patients with MEN1. (68)Gallium-DOTATATE PET/CT detected 107 lesions; (111)In-pentetreotide SPECT/CT detected 33 lesions; and CT scan detected 48 lesions. Lesions detected on (68)Gallium-DOTATATE PET/CT had high standard uptake value (SUV)(max) (median SUV(max) = 72.8 [range 19 to 191]). In 7 of the 26 patients (27%), (68)Gallium-DOTATATE PET/CT was positive, with a negative (111)In-pentetreotide SPECT/CT, and in 10 patients (38.5%), additional metastases were detected (range 0.3 cm to 1.5 cm). In 8 of the 26 patients (31%), there was a change in management recommendations as a result of the findings on (68)Gallium-DOTATATE PET/CT that were not seen on (111)In-pentetreotide SPECT/CT and CT scan. (68)Gallium-DOTATATE PET/CT is more sensitive for detecting NETs than (111)In-pentetreotide SPECT/CT and CT scan in patients with MEN1. This imaging technique should be integrated into radiologic screening and surveillance of patients with MEN1 because it can significantly alter management recommendations. Published by Elsevier Inc.

  9. Impact of PET/CT system, reconstruction protocol, data analysis method, and repositioning on PET/CT precision: An experimental evaluation using an oncology and brain phantom.

    Science.gov (United States)

    Mansor, Syahir; Pfaehler, Elisabeth; Heijtel, Dennis; Lodge, Martin A; Boellaard, Ronald; Yaqub, Maqsood

    2017-12-01

    In longitudinal oncological and brain PET/CT studies, it is important to understand the repeatability of quantitative PET metrics in order to assess change in tracer uptake. The present studies were performed in order to assess precision as function of PET/CT system, reconstruction protocol, analysis method, scan duration (or image noise), and repositioning in the field of view. Multiple (repeated) scans have been performed using a NEMA image quality (IQ) phantom and a 3D Hoffman brain phantom filled with 18 F solutions on two systems. Studies were performed with and without randomly (PET/CT, especially in the case of smaller spheres (PET metrics depends on the combination of reconstruction protocol, data analysis methods and scan duration (scan statistics). Moreover, precision was also affected by phantom repositioning but its impact depended on the data analysis method in combination with the reconstructed voxel size (tissue fraction effect). This study suggests that for oncological PET studies the use of SUVpeak may be preferred over SUVmax because SUVpeak is less sensitive to patient repositioning/tumor sampling. © 2017 The Authors. Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  10. Brain shrinking in chronic alcoholism: CT follow-up study in 65 patients

    Energy Technology Data Exchange (ETDEWEB)

    Schroth, G.; Remmes, U.; Schupmann, A.

    1985-04-01

    CT follow-up studies were done in 65 alcoholics before an inpatient treatment and after a period with confirmed abstinence of 5 weeks duration. The scans were rated 'blind' by linear measurement of well defined distances. An improvement (Significant reduction of brain 'atrophy') was found in 33 patients (50.8%), 5 patients (7,7%) showed a trend towards progression of brain 'atrophy'. The possibility of recovery tends to be significantly greater in younger subjects. These findings and the results of recent MR follow-up studies are consistent with decreased free water during alcohol intoxication and an increase in brain water during alcohol withdrawal.

  11. Reduction scan time pitch for media measurement procedures ITV in lung cancer with CT-CT fusion; Reduccion de pitch para scantime medios en procedimientos de medida de ITV en cancer de pulmon con fusion CT-CT

    Energy Technology Data Exchange (ETDEWEB)

    Velazquez Miranda, S.; Ramirez Gutierrez, Y.; Rodriguez Alarcon, C.; Herrador Cordoba, M.

    2011-07-01

    The evolution of CT technology has led to the non-specific scanners for radiotherapy the scan time maximum is reduced to 2 seconds. This forces us to change the procedure for obtaining similar results.

  12. The profile of CT scan findings in acute head trauma in Orotta ...

    African Journals Online (AJOL)

    The use of investigation modalities are influenced by socioeconomic and cost effectiveness of the tests. Objective and methods: The purpose of the present five months observational study was to describe the profile of cranial computed tomography (CT) scan findings of 110 cases of acute head trauma in Orotta Hospital.

  13. Lumbosacral lipoma investigated by conventional radiography, ultrasound and direct coronal mode CT-scanning.

    Science.gov (United States)

    Hageman, G; Veiga-Pires, J A; de Graaff, R; vd Beek, R; Probst, F; Ramos, L

    1982-06-01

    The authors describe a case of lipoma of the lumbosacral region, associated with meningocele in an infant and advocate the utilization of CT scanning in direct coronal mode (DCM) and ultrasound (US) as means of diagnosis of the extension and geography of the lesion and differential diagnosis. The surgical management is also indicated.

  14. Implant planning and placement using optical scanning and cone beam CT technology

    NARCIS (Netherlands)

    van der Zel, J.M.

    2008-01-01

    There is a growing interest in minimally invasive implant therapy as a standard prosthodontic treatment, providing complete restoration of occlusal function. A new treatment method (CADDIMA), which combines both computerized tomographic (CT) and optical laser-scan data for planning and design of

  15. Abnormal CT scan in a patient with Gilles de la Tourette syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Kjaer, M.; Boris, P.; Gadegaard Hansen, L.

    1986-07-01

    In a 28-year-old woman, who presented multiple muscular and vocal tics, typical of Gilles de la Tourette syndrome, CT scans revealed a large porencephalic cyst in the right hemisphere involving the right basal ganglia, as well as contrast enhancement in the region of the left basal ganglia.

  16. Preliminary report on a new mode of CT-scanning of the thorax

    NARCIS (Netherlands)

    Veiga-Pires, J.A.; Kaiser, M.C.

    1980-01-01

    The A.A. advocate a “longitudino-axial” mode of CT-scanning in examinations of the thorax and suggest it as the standard mode in children and adults of small stature. The full development of the method is at present limited by the design of both hardware and software of the current generations of

  17. Quantifying the impact of µCT-scanning of human fossil teeth on ESR age results.

    Science.gov (United States)

    Duval, Mathieu; Martín-Francés, Laura

    2017-05-01

    Fossil human teeth are nowadays systematically CT-scanned by palaeoanthropologists prior to any further analysis. It has been recently demonstrated that this noninvasive technique has, in most cases, virtually no influence on ancient DNA preservation. However, it may have nevertheless an impact on other techniques, like Electron Spin Resonance (ESR) dating, by artificially ageing the apparent age of the sample. To evaluate this impact, we µCT-scanned several modern enamel fragments following the standard analytical procedures employed by the Dental Anthropology Group at CENIEH, Spain, and then performed ESR dose reconstruction for each of them. The results of our experiment demonstrate that the systematic high-resolution µCT-scanning of fossil hominin remains introduces a nonnegligible X-ray dose into the tooth enamel, equivalent to 15-30 Gy depending on the parameters used. This dose may be multiplied by a factor of ∼8 if no metallic filter is used. However, this dose estimate cannot be universally extrapolated to any µCT-scan experiment but has instead to be specifically assessed for each device and set of parameters employed. The impact on the ESR age results is directly dependent on the magnitude of the geological dose measured in fossil enamel but could potentially lead to an age overestimation up to 40% in case of Late Pleistocene samples, if not taken into consideration. © 2017 Wiley Periodicals, Inc.

  18. Severe cerebral toxoplasma infection cannot be excluded by a normal CT scan

    NARCIS (Netherlands)

    Weenink, J. J.; Weenink, A. G.; Geerlings, S. E.; van Gool, T.; Bemelman, F. J.

    2009-01-01

    A fatal case is reported concerning a severely immunocompromised 50-year-old female renal transplant recipient who developed fever and confusion. Cerebral imaging with contrast-enhanced computed tomography (CT) scans showed no abnormalities while subsequently performed magnetic resonance imaging

  19. Material investigation for manufacturing of reference step gauges for CT scanning verification

    DEFF Research Database (Denmark)

    Cantatore, Angela; Angel, Jais Andreas Breusch; De Chiffre, Leonardo

    2012-01-01

    This work deals with the study of stability and material investigation for manufacturing of step gauges for CT scanning verification. Four replica step gauges were fabricated using a bisacryl material for dental applications and the stability over five months was monitored using a tactile CMM...

  20. Is it possible to calculate surface areas of intraoral structures from preoperative CT scan?

    Science.gov (United States)

    Ramella, Vittorio; Bottosso, Stefano; Franchi, Alberto; Papa, Giovanni; Bussani, Rossana; Arnež, Zoran Marji

    2017-08-01

    Microsurgical reconstruction of intraoral structures requires accurate planning of flap shape and dimensions. The goal of this study is to describe a method that allows to calculate surfaces of oral structures from preoperative CT-scan in order to determine a precise flap design before the surgery. We created casts of the human mouth from cadavers with a head and neck CT-scan available using an impression material. We digitalized the mouth casts and unwrapped the surfaces of the different structures of the mouth in a bi-dimensional plane in order to measure the area. Furthermore, we measured distances from pre-determined bony landmarks using the CT-scan 3D reconstruction model and we correlated the two type of measurements. We performed a simple regression analysis and afterwards a multivariate analysis using the more statistically correlated measurements. We found a statistical correlation between the surface of the tongue and the surface floor of the mouth with three bone distances that let us to create three mathematical formulas. With those formulas, we can calculate the surfaces of the tongue and the floor of the mouth using simple bony distances that can be easily measured from the head and neck preoperative CT scan. Using standard template's layouts, we can create a precise preoperative flap design in the reconstruction of the tongue and of the floor of the mouth. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  1. Automatic segmentation of the pulmonary lobes from chest CT scans based on fissures, vessels, and bronchi

    NARCIS (Netherlands)

    Lassen, B.C.; Rikxoort, E.M. van; Schmidt, M.; Kerkstra, S.; Ginneken, B. van; Kuhnigk, J.

    2013-01-01

    Segmentation of the pulmonary lobes is relevant in clinical practice and particularly challenging for cases with severe diseases or incomplete fissures. In this work an automated segmentation approach is presented that performs a markerbased watershed transformation on {CT} scans to subdivide the

  2. Significance of CT scan and color Doppler duplex ultrasound in the assessment of Abernethy malformation.

    Science.gov (United States)

    Nacif, Lucas Souto; Paranaguá-Vezozzo, Denise Cerqueira; Galvão, Flávio Henrique Ferreira; Rocha, Manoel S; Andraus, Wellington; Carrilho, Flair Jose; D'Albuquerque, Luiz Carneiro

    2015-09-18

    Abernethy malformation is a rare congenital vascular abnormality in which the portal vein bypasses the liver and drains directly into the inferior vena cava. Diagnosis is complex and requires good quality imaging methods to identify details in systemic and portal circulation in order to establish diagnostic confirmation and treatment strategy. In this study we highlight the significance of the use of CT scans and Color Doppler Duplex Ultrasound for the diagnosis, treatment and evolution assessment in two adults with Abernethy malformation. The diagnosis and the treatment of two patients with Abernethy malformation by CT scan and Color Doppler Duplex Ultrasound is described. One patient was submitted to liver transplantation due to chronic liver disease and multiple nodules diagnosed as adenoma. The other patient had normal liver function and a mild neurological and psychomotor dysfunction, therefore we adopted clinical treatment and close liver parenchyma evaluation and nodule surveillance, using an imaging approach involving intercalating CT scan and Color Doppler Duplex Ultrasound every 6 months. We highlight some important direct and indirect findings of non-invasive imaging methods. Abernethy malformation requires meticulous image diagnosis to improve treatment and avoid iatrogenic procedures. CT scans and Color Doppler Duplex Ultrasound are both efficient methods for diagnosis, treatment planning and evolution assessment of patients with Abernethy malformation.

  3. Utility of CT scan for the diagnosis of chest wall tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Khalil, A.; Le Breton, C.; Tassart, M.; Korzec, J.; Bigot, J.M.; Carette, M.F. [Department of Radiology, Tenon Hospital, Paris (France)

    1999-10-01

    The objective of this study was to determine the utility of CT scan findings for the diagnosis of chest wall tuberculosis, excluding the spine. We reviewed 15 patients (13 Africans and 2 Indians) with chest wall tuberculosis, retrospectively. The radiologic examination consisted of a plain X-ray and a CT scan of the chest for each patient. The site of disease was the rib in 13 patients or the body of the sternum in 2 patients. One rib was involved in 11 patients, 2 contiguous ribs (one site) in 2 patients, and bilateral disease (two sites) was observed in the remaining patient. The 14 rib sites involved the posterior arc or costovertebral joint in 11 cases, the anterior arc in 2 cases, and the anterior and middle arc in 1 case. The CT scan findings were an abscess (n = 14) or a soft tissue mass (n = 2), osteolytic lesions (n = 13), periosteal reaction (n = 10), and sequestrum (n = 14). Bone sclerosis was observed only in 3 cases of rib involvement. The association of a soft tissue abscess, an osteolytic lesion, and sequestrum, especially in immigrants to France, suggests chest wall tuberculosis on CT scan. (orig.) With 5 figs., 2 tabs., 11 refs.

  4. Virtual teeth: a 3D method for editing and visualizing small structures in CT scans

    DEFF Research Database (Denmark)

    Bro-Nielsen, Morten; Larsen, Per; Kreiborg, Sven

    1996-01-01

    The paper presents an interactive method for segmentation and visualization of small structures in CT scans. A combination of isosurface generation, spatial region growing and interactive graphics tools are used to extract small structures interactively. A practical example of segmentation of the...

  5. Self-guided clinical cases for medical students based on postmortem CT scans of cadavers.

    Science.gov (United States)

    Bohl, Michael; Francois, Webster; Gest, Thomas

    2011-07-01

    In the summer of 2009, we began full body computed tomography (CT) scanning of the pre-embalmed cadavers in the University of Michigan Medical School (UMMS) dissection lab. We theorized that implementing web-based, self-guided clinical cases based on postmortem CT (PMCT) scans would result in increased student appreciation for the clinical relevance of anatomy, increased knowledge of cross-sectional anatomy, and increased ability to identify common pathologies on CT scans. The PMCT scan of each cadaver was produced as a DICOM dataset, and then converted into a Quicktime movie file using Osirix software. Clinical cases were researched and written by the authors, and consist of at least one Quicktime movie of a PMCT scan surrounded by a novel navigation interface. To assess the value of these clinical cases we surveyed medical students at UMMS who are currently using the clinical cases in their coursework. Students felt the clinical cases increased the clinical relevance of anatomy (mean response 7.77/10), increased their confidence finding anatomical structures on CT (7.00/10), and increased their confidence recognizing common pathologies on CT (6.17/10). Students also felt these clinical cases helped them synthesize material from numerous courses into an overall picture of a given disease process (7.01/10). These results support the conclusion that our clinical cases help to show students why the anatomy they are learning is foundational to their other coursework. We would recommend the use of similar clinical cases to any medical school utilizing cadaver dissection as a primary teaching method in anatomy education. Copyright © 2011 Wiley-Liss, Inc.

  6. Contrast enhanced CT-scan to diagnose intrahepatic cholangiocarcinoma in patients with cirrhosis.

    Science.gov (United States)

    Iavarone, Massimo; Piscaglia, Fabio; Vavassori, Sara; Galassi, Marzia; Sangiovanni, Angelo; Venerandi, Laura; Forzenigo, Laura Virginia; Golfieri, Rita; Bolondi, Luigi; Colombo, Massimo

    2013-06-01

    Contrast enhanced computed tomography (CT-scan) is a standard of care for the radiological diagnosis of hepatocellular carcinoma (HCC) in patients with cirrhosis. This technique, however, is not validated to exclude intrahepatic cholangiocarcinoma (ICC) which may develop in patients with cirrhosis, as well. To assess the features of contrast CT-scan in the diagnosis of ICC, we reviewed all CT-scan films obtained in cirrhotic patients with a histologically documented ICC, taking in consideration the pattern and dynamics of the arterial, portal venous and delayed phases of contrast uptake. Thirty-two patients had 40 nodules of ICC (22 male; median age 62years; 13 hepatitis C) that were identified either during surveillance with abdominal ultrasound (21 patients, 66%) or incidentally (11 patients, 34%). ICC was either multifocal or ≥ 30 mm in 11 of the former and 10 of the latter group (52% vs. 91%, pCT-scan, while the remaining 38 showed a heterogeneous contrast enhancement pattern, being the arterial peripheral-rim enhancement present in 19 (50%) cases and a progressive homogeneous contrast uptake in 16 (42%) cases during the three vascular phases, with no relation to tumor size. Importantly, all nodules lacked the radiological hallmark of HCC, the only ICC nodule showing a homogeneous wash-in during the arterial phase followed by a wash-out in the delayed venous phase, however showing a homogeneous wash-in during the portal phase too. ICC in cirrhotic patients displays distinct vascular patterns at CT-scan that allow for differentiation from HCC. Copyright © 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  7. Efficacy of Routine Postoperative CT Scan After Open Reduction and Internal Fixation of the Acetabulum.

    Science.gov (United States)

    Archdeacon, Michael T; Dailey, Steven K

    2015-08-01

    The purpose of this study was to evaluate the efficacy of routine postoperative computed tomography (CT) scan after open reduction and internal fixation of acetabular fractures. Retrospective review of prospectively collected acetabulum fracture database. Level I trauma center. A total of 606 consecutive patients underwent surgical fixation of 612 acetabular fractures. All patients were evaluated with intraoperative fluoroscopy in addition to 3 standard plain radiographs (AP pelvis and two 45 degrees oblique Judet views). Reduction and fixation were believed to be adequate and definitive before exiting the operative suite based on these imaging modalities. Axial postoperative CT scan of the pelvis was obtained in 563 of the patients (93%) after 569 operative cases. Revision acetabular surgery based on routine postoperative CT scan findings. There were no significant differences between index and revision surgery groups regarding age, gender, body mass index, fracture pattern, mechanism of injury, or surgical approach (P > 0.05). Evaluation of 563 postoperative CT scans of the pelvis resulted in revision acetabular surgery for 2.5% of patients (n = 14). There were 6 (1.1%) cases of intraarticular hardware not recognized on the intraoperative fluoroscopy or pelvic radiographs. Four patients (0.7%) had residual intraarticular osteochondral fragments deemed too large to leave in the hip joint. There were 3 cases (0.5%) of unacceptable malreduction, and 1 case (0.2%) of both malreduction and an intraarticular osteochondral fragment. A small percentage of patients (2.5%) will benefit from a routine CT scan after acetabular fracture fixation. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

  8. Prediction of stroke thrombolysis outcome using CT brain machine learning

    Directory of Open Access Journals (Sweden)

    Paul Bentley

    2014-01-01

    Full Text Available A critical decision-step in the emergency treatment of ischemic stroke is whether or not to administer thrombolysis — a treatment that can result in good recovery, or deterioration due to symptomatic intracranial haemorrhage (SICH. Certain imaging features based upon early computerized tomography (CT, in combination with clinical variables, have been found to predict SICH, albeit with modest accuracy. In this proof-of-concept study, we determine whether machine learning of CT images can predict which patients receiving tPA will develop SICH as opposed to showing clinical improvement with no haemorrhage. Clinical records and CT brains of 116 acute ischemic stroke patients treated with intravenous thrombolysis were collected retrospectively (including 16 who developed SICH. The sample was split into training (n = 106 and test sets (n = 10, repeatedly for 1760 different combinations. CT brain images acted as inputs into a support vector machine (SVM, along with clinical severity. Performance of the SVM was compared with established prognostication tools (SEDAN and HAT scores; original, or after adaptation to our cohort. Predictive performance, assessed as area under receiver-operating-characteristic curve (AUC, of the SVM (0.744 compared favourably with that of prognostic scores (original and adapted versions: 0.626–0.720; p < 0.01. The SVM also identified 9 out of 16 SICHs, as opposed to 1–5 using prognostic scores, assuming a 10% SICH frequency (p < 0.001. In summary, machine learning methods applied to acute stroke CT images offer automation, and potentially improved performance, for prediction of SICH following thrombolysis. Larger-scale cohorts, and incorporation of advanced imaging, should be tested with such methods.

  9. "High-precision, reconstructed 3D model" of skull scanned by conebeam CT: Reproducibility verified using CAD/CAM data.

    Science.gov (United States)

    Katsumura, Seiko; Sato, Keita; Ikawa, Tomoko; Yamamura, Keiko; Ando, Eriko; Shigeta, Yuko; Ogawa, Takumi

    2016-01-01

    Computed tomography (CT) scanning has recently been introduced into forensic medicine and dentistry. However, the presence of metal restorations in the dentition can adversely affect the quality of three-dimensional reconstruction from CT scans. In this study, we aimed to evaluate the reproducibility of a "high-precision, reconstructed 3D model" obtained from a conebeam CT scan of dentition, a method that might be particularly helpful in forensic medicine. We took conebeam CT and helical CT images of three dry skulls marked with 47 measuring points; reconstructed three-dimensional images; and measured the distances between the points in the 3D images with a computer-aided design/computer-aided manufacturing (CAD/CAM) marker. We found that in comparison with the helical CT, conebeam CT is capable of reproducing measurements closer to those obtained from the actual samples. In conclusion, our study indicated that the image-reproduction from a conebeam CT scan was more accurate than that from a helical CT scan. Furthermore, the "high-precision reconstructed 3D model" facilitates reliable visualization of full-sized oral and maxillofacial regions in both helical and conebeam CT scans. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. Variation compensation and analysis on diaphragm curvature analysis for emphysema quantification on whole lung CT scans

    Science.gov (United States)

    Keller, Brad M.; Reeves, Anthony P.; Barr, R. Graham; Yankelevitz, David F.; Henschke, Claudia I.

    2010-03-01

    CT scans allow for the quantitative evaluation of the anatomical bases of emphysema. Recently, a non-density based geometric measurement of lung diagphragm curvature has been proposed as a method for the quantification of emphysema from CT. This work analyzes variability of diaphragm curvature and evaluates the effectiveness of a compensation methodology for the reduction of this variability as compared to emphysema index. Using a dataset of 43 scan-pairs with less than a 100 day time-interval between scans, we find that the diaphragm curvature had a trend towards lower overall variability over emphysema index (95% CI:-9.7 to + 14.7 vs. -15.8 to +12.0), and that the variation of both measures was reduced after compensation. We conclude that the variation of the new measure can be considered comparable to the established measure and the compensation can reduce the apparent variation of quantitative measures successfully.

  11. Risk factors indicating the need for cranial CT scans in elderly patients with head trauma: an Austrian trial and comparison with the Canadian CT Head Rule.

    Science.gov (United States)

    Wolf, Harald; Machold, Wolfgang; Frantal, Sophie; Kecht, Mathias; Pajenda, Gholam; Leitgeb, Johannes; Widhalm, Harald; Hajdu, Stefan; Sarahrudi, Kambiz

    2014-02-01

    This study presents newly defined risk factors for detecting clinically important brain injury requiring neurosurgical intervention and intensive care, and compares it with the Canadian CT Head Rule (CCHR). This prospective cohort study was conducted in a single Austrian Level-I trauma center and enrolled a consecutive sample of mildly head-injured adults who presented to the emergency department with witnessed loss of consciousness, disorientation, or amnesia, and a Glasgow Coma Scale (GCS) score of 13-15. The studied population consisted of a large number of elderly patients living in Vienna. The aim of the study was to investigate risk factors that help to predict the need for immediate cranial CT in patients with mild head trauma. Among the 12,786 enrolled patients, 1307 received a cranial CT scan. Four hundred eighty-nine patients (37.4%) with a mean age of 63.9 ± 22.8 years had evidence of an acute traumatic intracranial lesion on CT. Three patients ( 65 years, loss of consciousness, nausea or vomiting, hypocoagulation, dementia or a history of ischemic stroke, anisocoria, skull fracture, and development of a focal neurological deficit. Patients requiring neurosurgical intervention were detected with a sensitivity of 90% and a specificity of 67% by using the authors' analysis. In contrast, the use of the CCHR in these patients detected the need for neurosurgical intervention with a sensitivity of only 80% and a specificity of 72%. The use of the suggested parameters proved to be superior in the detection of high-risk patients who sustained a mild head trauma compared with the CCHR rules. Further validation of these results in a multicenter setting is needed. Clinical trial registration no.: NCT00451789 ( ClinicalTrials.gov .).

  12. Study of CT head scans using different voltages: image quality evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Pacheco de Freitas C, I.; Prata M, A. [Centro Federal de Educacao Tecnologica de Minas Gerais, Centro de Engenharia Biomedica, Av. Amazonas 5253, 30421-169 Nova Suica, Belo Horizonte, Minas Gerais (Brazil); Alonso, T. C. [Centro de Desenvolvimento da Tecnologia Nuclear / CNEN, Av. Pte. Antonio Carlos 6627, 31270-901 Pampulha, Belo Horizonte, Minas Gerais (Brazil); Santana, P., E-mail: iarapfcorrea@gmail.com [Universidade Federal de Minas Gerais, Departamento de Anatomia e Imagem, Av. Prof. Alfredo Balena 190, 30130-100 Belo Horizonte, Minas Gerais (Brazil)

    2016-10-15

    Computed tomography (CT) was introduced to medical practice in 1972. It generates images recognized by high diagnostic potential. CT allows investigation of structures in the human body inaccessible by conventional image methods, replacing invasive methods in many cases. Noise is a kind of variation of brightness observed on CT images, and it is inherent to this method. The magnitude of the noise is determined by the standard deviation of CT numbers of a region of interest in a homogeneous material. The aim of this study is to analyze the noise in head CT images generated by different acquisition protocols using four voltage values. Five different scans were performed using a female Alderson phantom and their images were analyzed with the RadiAnt software. With the average HU values and standard deviation of each scan, the values of noise were calculated in some region of interest. The obtained noise values were compared and it was observed that the 140 kV voltage promotes the in the lower noise in the image, resulting in better image quality. The results also show that the parameters, such as voltage and current, can be adjusted so that the noise can be decreased. Thus, acquisition protocols may be adapted to produce images with diagnostic quality and lower doses in patient. (Author)

  13. [Progress in thin layer CT scan technology in estimating skeletal age of sternal end of clavicle].

    Science.gov (United States)

    Wang, Ya-Hui; Wei, Hua; Ying, Chong-Liang; Wan, Lei; Zhu, Guang-You

    2013-04-01

    It is practical value for determination the teenagers whether the age is full of the legal responsibility age of 18 years old or not by estimating skeletal age of sternal end of clavicle. The traditional methods mainly based on X-ray radiography. However, sternal end of clavicle and adjacent lung, bronchus, sternum, rib, transverse process of thoracic vertebra are overlapped each other. As a result of overlapping, there will be obtained false negative or positive film reading results when according to X-ray observation of epiphyseal growth of sternal end of clavicle, which directly affect the scientificalness and accuracy of estimating of skeletal age. In recent years, the scholars at home and abroad have started to use thin layer CT scan technology to estimate skeletal age of the sternal end of clavicle. With the 2D and 3D CT recombination technology, the accuracy of the film reading distinctly improves by making the shape, size and position of epiphysis displayed clearly. This article reviews the application and research progress of thin layer CT scanning technology in estimating skeletal age of sternal end of clavicle at home and abroad, analyzes the superiority and value of thin layer CT scan technology, which applied to skeletal age of sternal end of clavicle.

  14. Dose responses in a normoxic polymethacrylic acid gel dosimeter using optimal CT scanning parameters

    Science.gov (United States)

    Cho, K. H.; Cho, S. J.; Lee, S.; Lee, S. H.; Min, C. K.; Kim, Y. H.; Moon, S. K.; Kim, E. S.; Chang, A. R.; Kwon, S. I.

    2012-05-01

    The dosimetric characteristics of normoxic polymethacrylic acid gels are investigated using optimal CT scanning parameters and the possibility of their clinical application is also considered. The effects of CT scanning parameters (tube voltage, tube current, scan time, slick thickness, field of view, and reconstruction algorithm) are experimentally investigated to determine the optimal parameters for minimizing the amount of noise in images obtained using normoxic polymethacrylic acid gel. In addition, the dose sensitivity, dose response, accuracy, and reproducibility of the normoxic polymethacrylic acid gel are evaluated. CT images are obtained using a head phantom that is fabricated for clinical applications. In addition, IMRT treatment planning is performed using a Tomotherapy radiation treatment planning system. A program for analyzing the results is produced using Visual C. A comparison between the treatment planning and the CT images of irradiated gels is performed. The dose sensitivity is found to be 2.41±0.04 HGy-1. The accuracies of dose evaluation at doses of 2 Gy and 4 Gy are 3.0% and 2.6%, respectively, and their reproducibilities are 2.0% and 2.1%, respectively. In the comparison of gel and Tomotherpay planning, the pass rate of the γ-index, based on the reference values of a dose error of 3% and a DTA of 3 mm, is 93.7%.

  15. Reduction in radiation dose with reconstruction technique in the brain perfusion CT

    Science.gov (United States)

    Kim, H. J.; Lee, H. K.; Song, H.; Ju, M. S.; Dong, K. R.; Chung, W. K.; Cho, M. S.; Cho, J. H.

    2011-12-01

    The principal objective of this study was to verify the utility of the reconstruction imaging technique in the brain perfusion computed tomography (PCT) scan by assessing reductions in the radiation dose and analyzing the generated images. The setting used for image acquisition had a detector coverage of 40 mm, a helical thickness of 0.625 mm, a helical shuttle mode scan type and a rotation time of 0.5 s as the image parameters used for the brain PCT scan. Additionally, a phantom experiment and an animal experiment were carried out. In the phantom and animal experiments, noise was measured in the scanning with the tube voltage fixed at 80 kVp (kilovolt peak) and the level of the adaptive statistical iterative reconstruction (ASIR) was changed from 0% to 100% at 10% intervals. The standard deviation of the CT coefficient was measured three times to calculate the mean value. In the phantom and animal experiments, the absorbed dose was measured 10 times under the same conditions as the ones for noise measurement before the mean value was calculated. In the animal experiment, pencil-type and CT-dedicated ionization chambers were inserted into the central portion of pig heads for measurement. In the phantom study, as the level of the ASIR changed from 0% to 100% under identical scanning conditions, the noise value and dose were proportionally reduced. In our animal experiment, the noise value was lowest when the ASIR level was 50%, unlike in the phantom study. The dose was reduced as in the phantom study.

  16. Aphasia caused by intracerebral hemorrhage; CT-scan findings and prognosis

    Energy Technology Data Exchange (ETDEWEB)

    Furuya, Kazuhide; Segawa, Hiromu; Shiokawa, Yoshiaki; Hasegawa, Isao; Sano, Keiji (Fuji Brain Institute and Hospital, Shizuoka (Japan))

    1992-10-01

    It is generally accepted that cases of aphasia can be divided into several groups according to verbal fluency, auditory comprehension, and repetition abilities. Although many authors have studied aphasia and its location by means of a CT scan, the primary lesion on a CT scan with regard to the subtypes of aphasia still remains controversial. In this report we present our new CT classification for the syndromes of aphasia and the prognosis. Twenty-one patients with intracerebral hematoma (ICH) were followed up for more than 3 months after onset. ICH was classified according to the mode of the horizontal extension of the hematoma on a CT scan. Four lines were decided as follows: Line (a) is between the anterior horn of the lateral ventricle and the midpoint of the third ventricle; Line (b) is the vertical line to the saggital line which originates from the midpoint of the third ventricle; Line (c) is between the trigone of the lateral ventricle and the midpoint of the third ventricle. The CT classification consisted of 4 types: in Type A, ICH was located anterior to line (a); in Type B, ICH was located between line (a) and line (b); in Type C, ICH was located between line (b) and line (c); Type B+C, was a combination of Type B and Type C. Transcortical motor aphasia belonged to the Type A group. Transcortical sensory aphasia belonged to the Type B and Type B+C groups. Wernicke's and anomic aphasia belonged to the Type C group. Conduction and global aphasia belonged to the Type B+C group. Pure Broca's aphasia could not be observed in this series. Several relationships between the syndromes of aphasia and its CT findings were evident. On the other hand, the syndromes of aphasia and the degree of recovery were not correlated, except for global aphasia. (author).

  17. Diagnosis of gynecologic pelvic masses by CT scan. Cases that were difficult to diagnose

    Energy Technology Data Exchange (ETDEWEB)

    Ito, H.; Kubo, A.; Takagi, Y. (Keio Univ., Tokyo (Japan). School of Medicine); Kinoshita, Fumio; Maekawa, A.

    1981-05-01

    It is sometimes difficult to diagnose the gynecologic pelvic masses exactly by CT scan, because some different diseases have certain CT findings of resemblance to each other. It was not so easy to differentiate degenerated leiomyoma of the uterus, degenerated ovarian fibroma, and leiomyoma with pregnancy, if they had central low density areas. Early stage serous cystadenocarcinoma without tumor wall thickness and solid areas in the tumor was confused with serous cystadenoma. When mucinous cystadenoma and struma ovarii had protruding solid areas in their cystic tumors, they would be likely miss-diagnosed as malignant lesions.

  18. Extracranial tumor vascularity: determination by dynamic CT scanning. Part II. The unit approach

    Energy Technology Data Exchange (ETDEWEB)

    Som, P.M.; Lanzieri, C.F.; Sacher, M.; Lawson, W.; Biller, H.F.

    1985-02-01

    Twenty-eight patients had combined conventional drip infusion CT scans. The information about the anatomic location of the lesion, its configuration, its cross-sectional appearance, its vacularity (as determined by dynamic signature curves), and its clinical presentation were considered as a single overall unit. This diagnostic approach allowed a diagnosis to be made on virtually all of these enhancing lesions without resorting to either a digital venous imaging study or angiographic procedure. In 17 of these cases, such an invasive second procedure was performed either to confirm the CT impression as part of this study or as part of a therapeutic embolization procedure.

  19. [Creation and Evaluation of Educational Programs for Additional Delayed Scan of FDG-PET/CT].

    Science.gov (United States)

    Wada, Ryota; Kamiya, Takashi; Fujino, Kouichi; Ueda, Junpei; Isohashi, Kayako; Tatsumi, Mitsuaki; Hatazawa, Jun

    Generally, FDG-PET/CT image is acquired at the 60th minute after tracer administration. Depending on the clinical case, additional delayed scans may be useful. However, it is difficult to judge whether additional delayed scan is useful or not. The purposes of this study were creation and evaluation of educational programs to help radiological technologists to decide the usefulness of additional delayed scan of FDG-PET/CT. Educational programs consisted of the instructional materials and the judgment test of clinical cases. The instructional materials provided the valuable findings for differentiation between uptake in the wall of the colon and colon content, distinction between uptake in the lymph node and urinary tract, and evaluation of malignancy. The judgment test of clinical cases consisted of 10 cases selected by a nuclear medicine physician (for 5 of that cases additional delayed scan was decided to be useful). Five experienced technologists and five inexperienced technologists scored the volubility of additional delayed scan pre- and post-training using the instructional materials (the full marks of score is 5). After the educational programs using the instructional materials, the score was improved with the significant difference in both experienced (pre: 3.6±1.4, post: 4.0±1.2) and inexperienced (pre: 2.8±1.5, post: 3.7±1.5) groups (peducational programs, technologist might be able to decide whether the additional delayed scan is useful or not. The successful results of this study may improve the interpretation or reduce the total exposure dose of the PET/CT scan.

  20. Evaluation of the image quality of chest CT scans: a phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Martins N, P. I.; Prata M, A., E-mail: priscillainglid@gmail.com [Centro Federal de Educacao Tecnologica de Minas Gerais, Centro de Engenharia Biomedica, Av. Amazonas 5253, 30421-169 Nova Suica, Belo Horizonte, Minas Gerais (Brazil)

    2016-10-15

    Computed tomography (CT) is considered one of the most important methods of medical imaging employed nowadays, due to its non-invasiveness and the high quality of the images it is able to generate. However, the diagnostic radiation dose received by an individual over the year often exceeds the dose received on account of background radiation. Therefore, it is important to know and to control the dose distribution in the patient by varying the image acquisition parameters. The aim of this study is to evaluate the variation of the image quality of chest CT scans performed by two phantoms. In this paper, a cylindrical Polymethyl Methacrylate (PMMA) chest phantom was used and a second PMMA phantom has been developed with the same volume but an oblong shape, based on the actual dimensions of a male human thorax, in the axillary region. Ten-centimeter scans of the central area of each phantom were performed by a 16-channel Toshiba CT scanner, model Alexion. The scanning protocol employed was the radiology service protocol for chest scans. The noise survey was conducted within the image of the center slice, in five regions: one central and four peripheral areas close to the edge of the object (anterior, posterior, left and right). The recorded values showed that the oblong phantom, with a shape that is more similar to the actual human chest, has a considerably smaller noise, especially in the anterior, posterior and central regions. (Author)

  1. Evaluation in the use of bismuth shielding on cervical spine CT scan using a male phantom

    Energy Technology Data Exchange (ETDEWEB)

    Aleme, C.; Mourao, A. P. [Centro Federal de Educacion Tecnologica de Minas Gerais, Biomedical Engineering Center, Belo Horizonte - MG (Brazil); Lyra, M. A., E-mail: carolinaaleme@gmail.com [Universidad Federal de Minas Gerais, Department of Nuclear Engineering, Av. Pdte. Antonio Carlos 6627, Pampulha, 31270-91 Belo Horizonte - MG (Brazil)

    2014-08-15

    The cervical spine is the region of the column that articulates the head and chest. The tests of computed tomography (CT) performed in this region have as main objectives to diagnose fractures, dislocations and tumors. In CT scans the cervical spine volume is limited by the foramen Magnum and the first thoracic vertebra. In this region is the thyroid that is directly irradiated by X-ray beam during cervical scan. Based on this information, it was studied the dose variation deposited in thyroid and in nearby organs, such as: lenses, spinal cord in the foramen Magnum region and breasts, with and without the use of bismuth protector. In this study was used a male anthropomorphic phantom and thermoluminescent s dosimeters (TLD-100) were required to register the individual doses in the organs of interest. CT scans were performed on a GE Bright Speed scanner of 32 channels. With the data obtained, it was found the organ dose variation. The largest recorded dose was in the thyroid. Comparing two scans it was possible to note that the use of the bismuth protector promoted a 26% reduction in the thyroid dose and an increase in the lens dose. (Author)

  2. A novel sedimentological method based on CT-scanning: Use for tomographic characterization of the Galicia Interior Basin

    Science.gov (United States)

    Mena, Anxo; Francés, Guillermo; Pérez-Arlucea, Marta; Aguiar, Pablo; Barreiro-Vázquez, José Daniel; Iglesias, Alfredo; Barreiro-Lois, Andrés

    2015-05-01

    Non-destructive techniques of core analysis, especially of marine cores, are being broadly employed for sedimentary, paleoceanographic and paleoclimate research. In particular, Computed Tomography scanning (CT-scanning) allows acquisition of 3D and 2D images, according to desired planes, and thus the identification of sedimentary structures, large grains and their distributions as well as direct measurements of material densities. The most significant contribution of this technique is the possibility of getting results before opening the core. In this work CT-scan data obtained for five cores from the Galicia Interior Basin (GIB, NW Peninsula Iberia) are presented and discussed, focussing on (1) methodology of the CT-scan use, (2) tomographic description of sedimentary facies identified in the GIB, (3) treatment of the numeric data obtained with CT-scanning using specific software (anidoC), and (4) comparison of tomographic data with data obtained by conventional methodologies of core analysis. The most singular feature of GIB cores is the presence of Ice Rafted Debris (IRD) deposited during late Pleistocene Heinrich Events (HE), which can be easily recognized using the CT-scan by the presence of high radio-density grains immersed in a low radio-density matrix. Comparison of CT-scan data with analytical sedimentary data and HE proxies performed on the cores validates the CT-scanning method as a powerful tool to improve correlations, identify well-constrained events, and make more accurate basin reconstructions without opening all the cores in an oceanographic study.

  3. CT scan

    Science.gov (United States)

    ... stopping. A computer creates separate images of the body area, called slices. These images can be stored, viewed on a monitor, or printed on film. Three-dimensional models of the body area can ...

  4. CT Scan

    Science.gov (United States)

    ... available for medical professionals. Get updates. . Provider Relations Online Services for Referring Physicians Video Center Publications Continuing Medical Education Mayo Medical Laboratories ...

  5. Clinical study on eating disorders. Brain atrophy revealed by cranial computed tomography scans

    Energy Technology Data Exchange (ETDEWEB)

    Nishiwaki, Shinichi

    1988-06-01

    Cranial computed tomography (CT) scans were reviewed in 34 patients with anorexia nervosa (Group I) and 22 with bulimia (Group II) to elucidate the cause and pathological significance of morphological brain alterations. The findings were compared with those from 47 normal women. The incidence of brain atrophy was significantly higher in Group I (17/34, 50%) and Group II (11/22, 50%) than the control group (3/47, 6%). In Group I, there was a significant increase in the left septum-caudate distance, the maximum width of interhemispheric fissure, the width of the both-side Sylvian fissures adjacent to the skull, and the maximum width of the third ventricle. A significant increase in the maximum width of interhemispheric fissure and the width of the left-side Sylvian fissure adjacent to the skull were noted as well in Group II. Ventricular brain ratios were significantly higher in Groups I and II than the control group (6.76 and 7.29 vs 4.55). Brain atrophy did not correlate with age, body weight, malnutrition, eating behavior, depression, thyroid function, EEG findings, or intelligence scale. In Group I, serum cortisol levels after the administration of dexamethasone were correlated with ventricular brain ratio. (Namekawa, K) 51 refs.

  6. Comparison of adaptive statistical iterative and filtered back projection reconstruction techniques in brain CT

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Qingguo, E-mail: renqg83@163.com [Department of Radiology, Hua Dong Hospital of Fudan University, Shanghai 200040 (China); Dewan, Sheilesh Kumar, E-mail: sheilesh_d1@hotmail.com [Department of Geriatrics, Hua Dong Hospital of Fudan University, Shanghai 200040 (China); Li, Ming, E-mail: minli77@163.com [Department of Radiology, Hua Dong Hospital of Fudan University, Shanghai 200040 (China); Li, Jianying, E-mail: Jianying.Li@med.ge.com [CT Imaging Research Center, GE Healthcare China, Beijing (China); Mao, Dingbiao, E-mail: maodingbiao74@163.com [Department of Radiology, Hua Dong Hospital of Fudan University, Shanghai 200040 (China); Wang, Zhenglei, E-mail: Williswang_doc@yahoo.com.cn [Department of Radiology, Shanghai Electricity Hospital, Shanghai 200050 (China); Hua, Yanqing, E-mail: cjr.huayanqing@vip.163.com [Department of Radiology, Hua Dong Hospital of Fudan University, Shanghai 200040 (China)

    2012-10-15

    Purpose: To compare image quality and visualization of normal structures and lesions in brain computed tomography (CT) with adaptive statistical iterative reconstruction (ASIR) and filtered back projection (FBP) reconstruction techniques in different X-ray tube current–time products. Materials and methods: In this IRB-approved prospective study, forty patients (nineteen men, twenty-one women; mean age 69.5 ± 11.2 years) received brain scan at different tube current–time products (300 and 200 mAs) in 64-section multi-detector CT (GE, Discovery CT750 HD). Images were reconstructed with FBP and four levels of ASIR-FBP blending. Two radiologists (please note that our hospital is renowned for its geriatric medicine department, and these two radiologists are more experienced in chronic cerebral vascular disease than in neoplastic disease, so this research did not contain cerebral tumors but as a discussion) assessed all the reconstructed images for visibility of normal structures, lesion conspicuity, image contrast and diagnostic confidence in a blinded and randomized manner. Volume CT dose index (CTDI{sub vol}) and dose-length product (DLP) were recorded. All the data were analyzed by using SPSS 13.0 statistical analysis software. Results: There was no statistically significant difference between the image qualities at 200 mAs with 50% ASIR blending technique and 300 mAs with FBP technique (p > .05). While between the image qualities at 200 mAs with FBP and 300 mAs with FBP technique a statistically significant difference (p < .05) was found. Conclusion: ASIR provided same image quality and diagnostic ability in brain imaging with greater than 30% dose reduction compared with FBP reconstruction technique.

  7. Patellar subluxation syndrome. Observation of the patellofemoral joint using CT-scan

    Energy Technology Data Exchange (ETDEWEB)

    Yagi, Tomonori; Sasaki, Tetsuto; Susuda, Koichi; Moji, Junichi (Hokkaido Univ., Sapporo (Japan). School of Medicine)

    1983-10-01

    Clinical symptoms of patellar subluxation syndrome associated with pain were investigated for 24 knees of 20 patients, and the state of patella dislocation was observed by CT-scan. The patients had high incidence of an apprehension sign, showing their fear of patellar luxation. Many of them complained of patello-femoral joint pain due to chondromalacia patellae. In order to derive patellar subluxation, the method of CT-Q-contraction was carried out at the extended position of the patellar joint. In patients with patellar subluxation syndrome, the rate of shift in the diseased side was significantly higher than that of the other side, suggesting decreased muscular strength of the musculus vastus of the diseased side. Improvement of the symptoms was seen in all except one of 12 knees operated by the combined method of Green's method with Blauth's more than 6 months before. Availability of this operation was verified by the CT-Q-contraction.

  8. The Clinical Analysis on 32 Cases of Herniated Lumbar Disc Patients according to Lumbar CT scan

    Directory of Open Access Journals (Sweden)

    Jeong-ho Kim

    2010-06-01

    Full Text Available Objective : This study is to evaluate the effectiveness of the oriental medicine treatment on lumbar disc herniation. Subjects and Methods : The clinical analysis was done on 32 cases of patients with lumbar disc herniation diagnosed by lumbar CT scan. Patients who admitted in Cheongju Oriental Medicine Hospital from April 2007 to April 2008 were analyzed according to the distribution of sex, age, the period of disease, condition on admission, the symptom on admission, Admission day, the treatment efficacy at discharge day. Results : 1. The forties was the most, the acutest phase the most, the day of 8-14 days the most. 2. Multiple bulging disc in 37.5% of CT scan was the most common, followed by a single HNP was 28.1%. 3. Almost 81% patients showed effective efficacy under VAS 3 at discharge day. 4. Single bulging and herniated disc were more short admission days than multiple bulging and herniated disc.

  9. Diagnosis of strangulated small bowel obstruction; Efficacy of enhanced CT scanning

    Energy Technology Data Exchange (ETDEWEB)

    Mukai, Masaya; Noto, Takashi; Iwata, Yoshio (Tokai Univ., Isehara, Kanagawa (Japan). School of Medicine) (and others)

    1992-01-01

    We have experienced 25 cases of strangulated small bowel obstruction with bowel resection in the past 10 years. According to the histological findings in the resected bowel, these cases were divided into a necrotic group and a non-necrotic group. Preoperative findings on the clinical course and hematobiochemical examination in these two groups were compared, but no significant examination in these two groups were compared, but no significant differences were found. The results of enhanced CT scanning in these two groups were analyzed and some characteristic findings were seen in the necrotic group. Gasless small bowel, disappearance of the Kerckring's folds and increased mesenteric density were special features in the necrotic cases. Blurred enhancement of the small bowel wall and increased density of the bowel contents indicating bleeding were observed in the more severe cases. Enhanced CT scanning is very useful for diagnosing strangulated small bowel obstruction and should be used in cases of suspected necrotic bowel. (author).

  10. Computed assisted area measurement using CT scans. Clinical application for craniosynostosis in children

    Energy Technology Data Exchange (ETDEWEB)

    Morimoto, Kazuyoshi; Dehara, Makoto; Takemoto, Osamu [Osaka Medical Center and Research Inst. for Maternal and Child Health, Izumi (Japan); Hirano, Shun-ichiro; Yoshimine, Toshiki

    1999-11-01

    This paper describes a method for obtaining intracranial area measurements using CT scans with a soft ware for quantitative analysis of tracing data. A Toshiba CT 1010 scanner was used (120 kv, 10 mm slice thickness) to examine 13 children before and after cranioplastic surgery for craniosynostosis. Using Scion Image (Scion Corporation) with Intuos tablet system (WACOM), the intracranial space was measured at approximately same scanning level. Our findings show that the reverse pi and bilateral canthal advancement procedures usually carried out are associated with increased intracranial area, 4.5{+-}2.1% and 12.0{+-}8.3%, respectively. This measurement method should be further modified to intracranial volume gain by several surgical procedures. (author)

  11. Automatic segmentation and quantification of the cardiac structures from non-contrast-enhanced cardiac CT scans

    Science.gov (United States)

    Shahzad, Rahil; Bos, Daniel; Budde, Ricardo P. J.; Pellikaan, Karlijn; Niessen, Wiro J.; van der Lugt, Aad; van Walsum, Theo

    2017-05-01

    Early structural changes to the heart, including the chambers and the coronary arteries, provide important information on pre-clinical heart disease like cardiac failure. Currently, contrast-enhanced cardiac computed tomography angiography (CCTA) is the preferred modality for the visualization of the cardiac chambers and the coronaries. In clinical practice not every patient undergoes a CCTA scan; many patients receive only a non-contrast-enhanced calcium scoring CT scan (CTCS), which has less radiation dose and does not require the administration of contrast agent. Quantifying cardiac structures in such images is challenging, as they lack the contrast present in CCTA scans. Such quantification would however be relevant, as it enables population based studies with only a CTCS scan. The purpose of this work is therefore to investigate the feasibility of automatic segmentation and quantification of cardiac structures viz whole heart, left atrium, left ventricle, right atrium, right ventricle and aortic root from CTCS scans. A fully automatic multi-atlas-based segmentation approach is used to segment the cardiac structures. Results show that the segmentation overlap between the automatic method and that of the reference standard have a Dice similarity coefficient of 0.91 on average for the cardiac chambers. The mean surface-to-surface distance error over all the cardiac structures is 1.4+/- 1.7 mm. The automatically obtained cardiac chamber volumes using the CTCS scans have an excellent correlation when compared to the volumes in corresponding CCTA scans, a Pearson correlation coefficient (R) of 0.95 is obtained. Our fully automatic method enables large-scale assessment of cardiac structures on non-contrast-enhanced CT scans.

  12. Significance of clinical examination, CT and MRI scan in the diagnosis of posterior pelvic ring fractures.

    Science.gov (United States)

    Nüchtern, J V; Hartel, M J; Henes, F O; Groth, M; Jauch, S Y; Haegele, J; Briem, D; Hoffmann, M; Lehmann, W; Rueger, J M; Großterlinden, L G

    2015-02-01

    Patients with a fracture in the anterior pelvic ring often simultaneously demonstrate pain in the posterior pelvic ring. The aim of the present prospective study was to assess the sensitivity of CT, MRI and clinical examination in the detection of fractures in the posterior pelvic ring in patients with fractures of the anterior pelvic ring diagnosed in conventional radiographs. Sixty patients with radiographic signs of an anterior pelvic ring injury were included in this prospective analysis. Following a focused clinical examination of the posterior pelvis, all patients underwent both a CT and then a MRI scan of their pelvis. Two board certified radiologists evaluated the CT and MRI scans independently. To estimate the presence of osteoporosis the Hounsfield units of the vertebral body of L5 were measured in each case. Fifty-three women and seven men, with a mean age of 74.7+/-15.6 years were included into the study. A fracture of the posterior pelvic ring was found in fourty-eight patients (80%) patients using MRI. Fractures of the posterior pelvic ring would have been missed in eight cases (17%), if only CT had been used. Eighty-five percent of the patients with a posterior fracture had an osteoporosis. The majority of the cases suffered from a low energy trauma. Thirty-eight patients (83%) with positive clinical signs at the posterior pelvic ring actually had a fracture of the posterior pelvic ring in the MRI. The clinical examination proved to be equally effective to CT in detecting posterior pelvic ring fractures. The significance of both, clinical examination and CT was confirmed in the detection of fractures in the posterior pelvic ring. MRI examination of the pelvis however, was found to be superior in detecting undislocated fractures in a cohort of patients with a high incidence of osteoporosis. Using MRI may be beneficial in select cases, especially when reduced bone density is suspected. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Ossification defects detected in CT scans represent early osteochondrosis in the distal femur of piglets.

    Science.gov (United States)

    Olstad, Kristin; Kongsro, Jørgen; Grindflek, Eli; Dolvik, Nils Ivar

    2014-08-01

    The purpose of the current study was to validate the use of CT for selection against osteochondrosis in pigs by calculating positive predictive value and comparing it to the positive predictive value of macroscopic evaluation, using histological examination as the reference standard. Eighteen male, hereditarily osteochondrosis-predisposed piglets underwent terminal examination at biweekly intervals from the ages of 82-180 days old, including CT scanning, macroscopic, and histological evaluation of the left distal femur. Areas of ischemic chondronecrosis (osteochondrosis) were confirmed in histological sections from 44/56 macroscopically suspected lesions, resulting in a positive predictive value of 79% (95% CI: 67-84%). Suspected lesions, that is; focal, radiolucent defects in the ossification front in CT scans corresponded to areas of ischemic chondronecrosis in 36/36 histologically examined lesions, resulting in a positive predictive value of 100% (95% CI: 90-100%). CT was superior to macroscopic evaluation for diagnosis of early stages of osteochondrosis in the distal femur of piglets. The current histologically validated observations can potentially be extrapolated to diagnostic monitoring of juvenile osteochondritis dissecans in children, or to animal models of human juvenile articular cartilage injury and repair. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  14. Lumbar spine joint synovial cysts of intraspinal development. CT scan imaging

    Energy Technology Data Exchange (ETDEWEB)

    Vallee, C.; Chevrot, A.; Benhamouda, M. and others

    CT scan imaging findings are described in 22 patients with lumbar spine joint synovial cysts, of intraspinal development, provoking sciatica or lumbosciatica from nerve compression in spinal canal. Diagnosis was suggested by a mass at the posterior joint level, of variable density, sometimes with peripheral calcification, presenting a vacuum appearance on occasions, and with enhanced image with contrast. Differential diagnosis is from excluded hernia and postoperative fibrosis. Posterior intra-articular arthrography can confirm diagnosis and allow treatment with prolonged action corticoid infiltrations.

  15. Intraventricular tuberculoma. Report of four cases in children. [CT scan findings described

    Energy Technology Data Exchange (ETDEWEB)

    Berthier, M.; Sierra, J.; Leiguarda, R.

    1987-03-01

    Four cases of intraventricular tuberculoma (IVT) in children are here reported. In none of the patients was there clinical evidence pointing to the intraventricular location. CT scan findings comprised three stages of development, namely: immature, mature and old. Ependymal attachment and asymmetric hydrocephalus were present in three cases, meningitis in two and ependymitis in one. Septum pellucidum traction was clearly observed in two patients, strongly supporting an adhesive process characteristic of intraventricular tuberculosis. Following specific treatment, the tuberculomas remitted partially or entirely.

  16. Nonlinear 3D foot FEA modeling from CT scan medical images

    OpenAIRE

    Antunes, P. J.; Dias, Gustavo R.; Coelho, A. T.; Rebelo, F.; Pereira, Tiago

    2011-01-01

    A 3D anatomically detailed non-linear finite element analysis human foot model is the final result of density segmentation 3D reconstruction techniques applied in Computed Tomography (CT) scan DICOM standard images in conjunction with 3D Computer Aided Design operations and finite element analysis (FEA) modelling. Density segmentation techniques were used to geometrically define the foot bone structure and the encapsulated soft tissues configuration. The monitoring of the contact ...

  17. Traumatic cervical spinal cord injury with “negative” cervical spine CT scan

    OpenAIRE

    Kolli, Sreedhar; Schreiber, Adam; Harrop, James; Jallo, Jack

    2010-01-01

    A 46-year-old man fell four steps, striking his neck and having associated neck pain and discomfort. He was evaluated at a local emergency department and reported no neurological deficit but focal mid cervical tenderness. Radiographs and computed tomography (CT) scan were “negative” for cervical spine fracture, dislocation or pre-vertebral soft tissue swelling. He was discharged home in a cervical collar with a scheduled outpatient follow-up. Over the proceeding hours neurologic deterioration...

  18. Renal Tumor Cryoablation Planning. The Efficiency of Simulation on Reconstructed 3D CT Scan

    Directory of Open Access Journals (Sweden)

    Ciprian Valerian LUCAN

    2010-12-01

    Full Text Available Introduction & Objective: Nephron-sparing surgical techniques risks are related to tumor relationships with adjacent anatomic structures. Complexity of the renal anatomy drives the interest to develop tools for 3D reconstruction and surgery simulation. The aim of the article was to assess the simulation on reconstructed 3D CT scan used for planning the cryoablation. Material & Method: A prospective randomized study was performed between Jan. 2007 and July 2009 on 27 patients who underwent retroperitoneoscopic T1a renal tumors cryoablation (RC. All patients were assessed preoperatively by CT scan, also used for 3D volume rendering. In the Gr.A, the patients underwent surgery planning by simulation on 3D CT scan. In the Gr.B., patients underwent standard RC. The two groups were compared in terms of surgical time, bleeding, postoperative drainage, analgesics requirement, hospital stay, time to socio-professional reintegration. Results: Fourteen patients underwent preoperative cryoablation planning (Gr.A and 13 patients underwent standard CR (Gr.B. All parameters analyzed were shorter in the Gr.A. On multivariate logistic regression, only shortens of the surgical time (138.79±5.51 min. in Gr.A. vs. 140.92±5.54 min in Gr.B. and bleeding (164.29±60.22 mL in Gr.A. vs. 215.38±100.80 mL in Gr.B. achieved statistical significance (p<0.05. The number of cryoneedles assessed by simulation had a 92.52% accuracy when compared with those effectively used. Conclusions: Simulation of the cryoablation using reconstructed 3D CT scan improves the surgical results. The application used for simulation was able to accurately assess the number of cryoneedles required for tumor ablation, their direction and approach.

  19. Atlantoaxial Ankylosis Detected on Neck CT Scans in a Patient with Ankylosing Spondylitis: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Ah; Lee, Seung Hun; Joo, Kyung Bin [Dept. of Radiology, Seoul Hospital, Hanyang University College of Medicine, Seoul (Korea, Republic of); Ryu, Jeong Ah [Dept. of Radiology, Guri Hospital, Hanyang University College of Medicine, Guri (Korea, Republic of); Kim, Tae Hwan [Dept. of Rheynmatology, Seoul Hospital, Hanyang University College of Medicine, Seoul (Korea, Republic of)

    2011-07-15

    Ankylosing spondylitis is a chronic inflammatory disorder of unknown cause that principally affects the axial skeleton. The cervical spine is also vulnerable to this disease process and the characteristic feature of cervical involvement is atlantoaxial subluxation. However, only a few cases of atlantoaxial ankylosis have been reported to date. We report a case of atlantoaxial ankylosis in a patient with ankylosing spondylitis with radiologic findings incidentally detected on neck CT scans.

  20. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... with a new technique called Perfusion CT. brain tumors. enlarged brain cavities (ventricles) in patients with hydrocephalus . diseases or malformations of the skull. CT scanning is also performed to: evaluate the extent of bone and soft tissue damage in patients with facial ...

  1. A comparison between intrastomal 3D ultrasonography, CT scanning and findings at surgery in patients with stomal complaints.

    Science.gov (United States)

    Näsvall, P; Wikner, F; Gunnarsson, U; Rutegård, J; Strigård, K

    2014-10-01

    Since there are no reliable investigative tools for imaging parastomal hernia, new techniques are needed. The aim of this study was to assess the validity of intrastomal three-dimensional ultrasonography (3D) as an alternative to CT scanning for the assessment of stomal complaints. Twenty patients with stomal complaints, indicating surgery, were examined preoperatively with a CT scan in the supine position and 3D intrastomal ultrasonography in the supine and erect positions. Comparison with findings at surgery, considered to be the true state, was made. Both imaging methods, 3D ultrasonography and CT scanning, showed high sensitivity (ultrasound 15/18, CT scan 15/18) and specificity (ultrasound 2/2, CT scan 1/2) when judged by a dedicated radiologist. Corresponding values for interpretation of CT scans in routine clinical practice was for sensitivity 17/18 and for specificity 1/2. 3D ultrasonography has a high validity and is a promising alternative to CT scanning in the supine position to distinguish a bulge from a parastomal hernia.

  2. The effects of misinterpretation of an artefact on multidetector row CT scans in children.

    Science.gov (United States)

    du Plessis, Anne-Marie; Theron, Salomine; Andronikou, Savvas

    2009-02-01

    Artefacts reflect problems with radiographic technique rather than true pathology. These may be misinterpreted as pathology with serious consequences. An artefact caused such problems in one paediatric imaging department. To determine the incidence, and consequences of misinterpretation, of a CT artefact in a paediatric imaging department. A retrospective review of images and reports of paediatric CT scans over a set period with a known artefact was performed. Reports were correlated with reviewers' evaluation of the presence of artefact and reviewed for correct identification of artefact, misinterpretation as pathology, and action taken as a result. A total of 74 CT scans had been performed over the study period and an artefact detected by reviewers on 32 (43%). Six (18.75%) of these were misinterpreted as pathology, of which three (9.4%) were reported as tuberculous granulomas, two (6.2%) as haemorrhages and one (3.1%) as an unknown hyperdensity. Two patients (6.2%) had subsequent MRI studies performed, and treatment for tuberculosis was continued in one patient (3.1%). No initial report identified the artefact. One-fifth of the scans with the artefact were misinterpreted as pathology and half of these misinterpretations led to further action. Artefacts result in false diagnoses and unnecessary investigations; vigilance is needed.

  3. Classification of pulmonary emphysema from chest CT scans using integral geometry descriptors

    Science.gov (United States)

    van Rikxoort, E. M.; Goldin, J. G.; Galperin-Aizenberg, M.; Brown, M. S.

    2011-03-01

    To gain insight into the underlying pathways of emphysema and monitor the effect of treatment, methods to quantify and phenotype the different types of emphysema from chest CT scans are of crucial importance. Current standard measures rely on density thresholds for individual voxels, which is influenced by inspiration level and does not take into account the spatial relationship between voxels. Measures based on texture analysis do take the interrelation between voxels into account and therefore might be useful for distinguishing different types of emphysema. In this study, we propose to use Minkowski functionals combined with rotation invariant Gaussian features to distinguish between healthy and emphysematous tissue and classify three different types of emphysema. Minkowski functionals characterize binary images in terms of geometry and topology. In 3D, four Minkowski functionals are defined. By varying the threshold and size of neighborhood around a voxel, a set of Minkowski functionals can be defined for each voxel. Ten chest CT scans with 1810 annotated regions were used to train the method. A set of 108 features was calculated for each training sample from which 10 features were selected to be most informative. A linear discriminant classifier was trained to classify each voxel in the lungs into a subtype of emphysema or normal lung. The method was applied to an independent test set of 30 chest CT scans with varying amounts and types of emphysema with 4347 annotated regions of interest. The method is shown to perform well, with an overall accuracy of 95%.

  4. [Non-solid and part-solid pulmonary nodules on CT scanning].

    Science.gov (United States)

    Ferretti, G; Félix, L; Serra-Tosio, G; Brambilla, C; Moro-Sibilot, D; Brichon, P Y; Coulomb, M; Lantuejoul, S

    2007-12-01

    The entities of non-solid and part-solid pulmonary nodules on CT scan have been recently described. Nonsolid and part-solid pulmonary nodules account for between 2.9 and 19% of all pulmonary nodules detected in high-risk patients included in CT screening series for lung cancer. Radio-pathological correlations have shown that the aetiology could be either benign (chronic pneumonia, atypical adenomatous hyperplasia, localized fibrosis) or malignant (broncholoalveolar cell carcinoma, adenocarcinoma, more rarely metastasis). Part-solid or non-solid nodules are more likely to be malignant than solid ones. The doubling time of non-solid nodules can be longer than part-solid ones and even longer than the doubling time of solid nodules. Patient prognosis is related to the proportion of the ground glass component. The management of these nodules requires prolonged surveillance of nodules less than 10mm in diameter and surgical excision of nodules greater than 10mm persisting on scans between 1 to 3 months after they have been discovered and anti-inflammatory and anti-infectious therapy has been administered. Nonsolid and part-solid pulmonary nodules found on CT scan warrant a specific diagnostic workup.

  5. Analysis of the acetabulum by CT scan in Japanese with osteoarthritis of the hip

    Energy Technology Data Exchange (ETDEWEB)

    Ishibashi, Masanori [Keio Univ., Tokyo (Japan). School of Medicine

    1997-11-01

    The morphology of the acetabulum was analyzed by CT scan in 66 Japanese patients with osteoarthritis of the hip mainly following congenital dislocation or dysplasia. The CT scan data was analyzed to standardize the pelvic inclination in all directions. In these patients, the acetabular floor had thickened and the acetabulum was located in the anterolateral portion. The bilateral difference in the acetabular anteversion angle was not different between patients and normal individuals, but the acetabular sector angle in patients was smaller than in the normal subjects. As the stage of osteoarthritis of the hip advanced, the thickness of the acetabular floor in the center and posterior portions and the anterior sector angle increased, and the lateralization of the acetabulum advanced, but the anteversion angle decreased. A bone-forming change is characteristic of the anterior acetabulum and acetabular fossa in the center and posterior portions in Japanese patients with osteoarthritis of the hip. In comparison with data obtained by standard radiography, these changes detected by CT scan corresponded to an increase of the width of a tear drop, the lateralization of the femoral head and the lack of the support of the femoral head from the acetabulum. (author)

  6. Case of primary pontine hemorrhage of the young adult followed by CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Mashiyama, Shoji; Higuchi, Hiroshi; Takahashi, Akira

    1985-01-01

    A case of primary pontine hemorrhage of the young was reported. He was 22 years of age, who did not have the history of hypertension. He suddenly noticed disturbance of skilled act of his right hand and speech disturbance. He was admitted to our clinic two days after the onset. Neurological examination revealed right facial palsy, disturbance of delicate movement of his right hand and slight dysarthria. Lumbar puncture, after six days from the onset, yielded watery clear cerebrospinal fluid containing 6/3 cells/mm/sup 3/, 27mg/dl of protein and 65.1 mg/dl of sugar. An opening pressure was 75 mmH/sub 2/O. The vertebral angiography revealed no evidence of mass lesion and vascular anomalies. CT scan demonstrated a pontine hematoma, the size of this hematoma sequentially enlarged in follow-up CT scan. His clinical symptoms were gradually aggravated, i.e. cerebellar sign, urinary disturbance and involuntary movement. Conservative therapy was performed and his symptoms gradually improved. The size of hematoma was reduced in follow-up CT scan. The genesis, diagnosis and treatment of primary pontine hemorrhage of the young were discussed. (author).

  7. Classification of CT brain images based on deep learning networks.

    Science.gov (United States)

    Gao, Xiaohong W; Hui, Rui; Tian, Zengmin

    2017-01-01

    While computerised tomography (CT) may have been the first imaging tool to study human brain, it has not yet been implemented into clinical decision making process for diagnosis of Alzheimer's disease (AD). On the other hand, with the nature of being prevalent, inexpensive and non-invasive, CT does present diagnostic features of AD to a great extent. This study explores the significance and impact on the application of the burgeoning deep learning techniques to the task of classification of CT brain images, in particular utilising convolutional neural network (CNN), aiming at providing supplementary information for the early diagnosis of Alzheimer's disease. Towards this end, three categories of CT images (N = 285) are clustered into three groups, which are AD, lesion (e.g. tumour) and normal ageing. In addition, considering the characteristics of this collection with larger thickness along the direction of depth (z) (~3-5 mm), an advanced CNN architecture is established integrating both 2D and 3D CNN networks. The fusion of the two CNN networks is subsequently coordinated based on the average of Softmax scores obtained from both networks consolidating 2D images along spatial axial directions and 3D segmented blocks respectively. As a result, the classification accuracy rates rendered by this elaborated CNN architecture are 85.2%, 80% and 95.3% for classes of AD, lesion and normal respectively with an average of 87.6%. Additionally, this improved CNN network appears to outperform the others when in comparison with 2D version only of CNN network as well as a number of state of the art hand-crafted approaches. As a result, these approaches deliver accuracy rates in percentage of 86.3, 85.6 ± 1.10, 86.3 ± 1.04, 85.2 ± 1.60, 83.1 ± 0.35 for 2D CNN, 2D SIFT, 2D KAZE, 3D SIFT and 3D KAZE respectively. The two major contributions of the paper constitute a new 3-D approach while applying deep learning technique to extract signature information

  8. Malignant pleural mesothelioma with heterologous osteoblastic differentiation: case report of the characteristic CT and bone scan findings

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Young Jun; Kim, Joung Sook; Kim, Ji Young; Choi, Soo Jeon; Choi, Sang Bong [Sanggye Paik Hospital, Inje University College of Medicine, Seoul (Korea, Republic of)

    2008-06-15

    Malignant pleural mesothelioma is an uncommon neoplasm which is accompanied extremely rarely by osteoblastic heterologous elements. The CT manifestations of this tumor have been reported in several references. And, to our knowledge, only one case report provides a description of the bone scan findings. Here, we report the case of a rapidly progressing malignant pleural mesothelioma with heterologous osteoblastic elements. A CT scan reveals diffuse irregular pleural thickening and very coarse nodular calcifications along the right pleura and major fissure. A bone scan revealed an area of extensive increased radioactivity consistent with the pleural calcifications on the CT scan in the right hemithorax. A follow-up CT scan performed 40 days later suggests the presence of rapidly progressing nodular coarse calcifications.

  9. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    NARCIS (Netherlands)

    Mendrik, A.M.; Vonken, E.J.; Ginneken, B. van; Jong, H.W. de; Riordan, A.; Seeters, T. van; Smit, E.J.; Viergever, M.A.; Prokop, M.

    2011-01-01

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray

  10. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    NARCIS (Netherlands)

    A. Mendrik (Adrienne); E.J.P.A. Vonken; B.T.J. van Ginneken (Berbke); J.R. Riordan (John ); H.W.A.M. de Jong (Hugo); T. van Seeters (Tom); E.J. Smit (Ewoud); M.A. Viergever (Max); M. Prokop (Mathias)

    2011-01-01

    textabstractCerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of

  11. Carotid plaque characterization using CT and MRI scans for synergistic image analysis

    Science.gov (United States)

    Getzin, Matthew; Xu, Yiqin; Rao, Arhant; Madi, Saaussan; Bahadur, Ali; Lennartz, Michelle R.; Wang, Ge

    2014-09-01

    Noninvasive determination of plaque vulnerability has been a holy grail of medical imaging. Despite advances in tomographic technologies , there is currently no effective way to identify vulnerable atherosclerotic plaques with high sensitivity and specificity. Computed tomography (CT) and magnetic resonance imaging (MRI) are widely used, but neither provides sufficient information of plaque properties. Thus, we are motivated to combine CT and MRI imaging to determine if the composite information can better reflect the histological determination of plaque vulnerability. Two human endarterectomy specimens (1 symptomatic carotid and 1 stable femoral) were imaged using Scanco Medical Viva CT40 and Bruker Pharmascan 16cm 7T Horizontal MRI / MRS systems. μCT scans were done at 55 kVp and tube current of 70 mA. Samples underwent RARE-VTR and MSME pulse sequences to measure T1, T2 values, and proton density. The specimens were processed for histology and scored for vulnerability using the American Heart Association criteria. Single modality-based analyses were performed through segmentation of key imaging biomarkers (i.e. calcification and lumen), image registration, measurement of fibrous capsule, and multi-component T1 and T2 decay modeling. Feature differences were analyzed between the unstable and stable controls, symptomatic carotid and femoral plaque, respectively. By building on the techniques used in this study, synergistic CT+MRI analysis may provide a promising solution for plaque characterization in vivo.

  12. Multidetector row computed tomography of acute pancreatitis: Utility of single portal phase CT scan in short-term follow up

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Yongwonn [Department of Radiology, Konkuk University Medical Center, 4-12, Hwayang-dong, Gwangjin-gu, Seoul 143-729 (Korea, Republic of); Park, Hee Sun, E-mail: heesun.park@gmail.com [Department of Radiology, Konkuk University Medical Center, 4-12, Hwayang-dong, Gwangjin-gu, Seoul 143-729 (Korea, Republic of); Kim, Young Jun; Jung, Sung Il; Jeon, Hae Jeong [Department of Radiology, Konkuk University Medical Center, 4-12, Hwayang-dong, Gwangjin-gu, Seoul 143-729 (Korea, Republic of)

    2012-08-15

    Objective: The purpose of this study is to evaluate the question of whether nonenhanced CT or contrast enhanced portal phase CT can replace multiphasic pancreas protocol CT in short term monitoring in patients with acute pancreatitis. Materials and methods: This retrospective study was approved by the Institutional Review Board. From April 2006 to May 2010, a total of 52 patients having acute pancreatitis who underwent initial dual phase multidetector row CT (unenhanced, arterial, and portal phase) at admission and a short term (within 30 days) follow up dual phase CT (mean interval 10.3 days, range 3-28 days) were included. Two abdominal radiologists performed an independent review of three sets of follow up CT images (nonenhanced scan, single portal phase scan, and dual phase scan). Interpretation of each image set was done with at least 2-week interval. Radiologists evaluated severity of acute pancreatitis with regard to pancreatic inflammation, pancreatic necrosis, and extrapancreatic complication, based on the modified CT severity index. Scores of each image set were compared using a paired t-test and interobserver agreement was evaluated using intraclass correlation coefficient statistics. Results: Mean scores of sum of CT severity index on nonenhanced scan, portal phase scan, and dual phase scan were 5.7, 6.6, and 6.5 for radiologist 1, and 5.0, 5.6, and 5.8 for radiologist 2, respectively. In both radiologists, contrast enhanced scan (portal phase scan and dual phase scan) showed significantly higher severity score compared with that of unenhanced scan (P < 0.05), while portal phase and dual phase scan showed no significant difference each other. The trend was similar regarding pancreatic inflammation and extrapancreatic complications, in which contrast enhanced scans showed significantly higher score compared with those of unenhanced scan, while no significant difference was observed between portal phase scan and dual phase scan. In pancreatic necrosis

  13. Hierarchical pictorial structures for simultaneously localizing multiple organs in volumetric pre-scan CT

    Science.gov (United States)

    Montillo, Albert; Song, Qi; Das, Bipul; Yin, Zhye

    2015-03-01

    Parsing volumetric computed tomography (CT) into 10 or more salient organs simultaneously is a challenging task with many applications such as personalized scan planning and dose reporting. In the clinic, pre-scan data can come in the form of very low dose volumes acquired just prior to the primary scan or from an existing primary scan. To localize organs in such diverse data, we propose a new learning based framework that we call hierarchical pictorial structures (HPS) which builds multiple levels of models in a tree-like hierarchy that mirrors the natural decomposition of human anatomy from gross structures to finer structures. Each node of our hierarchical model learns (1) the local appearance and shape of structures, and (2) a generative global model that learns probabilistic, structural arrangement. Our main contribution is twofold. First we embed the pictorial structures approach in a hierarchical framework which reduces test time image interpretation and allows for the incorporation of additional geometric constraints that robustly guide model fitting in the presence of noise. Second we guide our HPS framework with the probabilistic cost maps extracted using random decision forests using volumetric 3D HOG features which makes our model fast to train and fast to apply to novel test data and posses a high degree of invariance to shape distortion and imaging artifacts. All steps require approximate 3 mins to compute and all organs are located with suitably high accuracy for our clinical applications such as personalized scan planning for radiation dose reduction. We assess our method using a database of volumetric CT scans from 81 subjects with widely varying age and pathology and with simulated ultra-low dose cadaver pre-scan data.

  14. Artefact on CT brain images caused by the presence of air bubbles in the cooling oil of the X-ray tube.

    Science.gov (United States)

    Trieu, Nelson; Xia, Ryan; Loneragan, Robert; Ridley, Lloyd; Trieu, Joseph

    2017-04-01

    We report a series of patients who had computed tomography (CT) of their brains which showed an uncommon artefact caused by excess air bubbles in the cooling oil around the X-ray tube. In November and December 2015, it was recognised that artefacts appearing on CT brain images acquired at our department were caused by a scanner fault. The test images were reviewed and the service engineer for the CT scanner was questioned about the artefact cause. A retrospective audit was then performed of images acquired on the CT scanner from December 2015 back to the date that the CT scanner was last serviced in September 2015 to identify any other scans affected by the artefact. Seven patients were identified whose CT brain scans showed the artefact. The artefact manifested in the form of an ill-defined low density area in varying locations. The artefact also appeared on CT phantom test images. It was discovered to be caused by the presence of excess air bubbles within the cooling oil of the X-ray tube. The fault was then rectified. The artefact described may not be easily recognised and could lead to misinterpretation and unnecessary investigation. We aim to promote awareness of this artefact and to reinforce the importance of frequent quality control testing of CT systems. © 2016 The Royal Australian and New Zealand College of Radiologists.

  15. Repeat CT-scan assessment of lymph node motion in locally advanced cervical cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Bondar, Luiza; Velema, Laura; Mens, Jan Willem; Heijmen, Ben; Hoogeman, Mischa [Erasmus Medical Center Cancer Institute, Department of Radiation Oncology, 3008 AE, Rotterdam (Netherlands); Zwijnenburg, Ellen [Radboud University Medical Center, Department of Radiation Oncology, Nijmegen (Netherlands)

    2014-12-15

    In cervical cancer patients the nodal clinical target volume (CTV, defined using the major pelvic blood vessels and enlarged lymph nodes) is assumed to move synchronously with the bony anatomy. The aim of this study was to verify this assumption by investigating the motion of the major pelvic blood vessels and enlarged lymph nodes visible in CT scans. For 13 patients treated in prone position, four variable bladder-filling CT scans per patient, acquired at planning and after 40 Gy, were selected from an available dataset of 9-10 CT scans. The bladder, rectum, and the nodal-vessels structure containing the iliac vessels and all visible enlarged nodes were delineated in each selected CT scan. Two online patient setup correction protocols were simulated. The first corrected bony anatomy translations and the second corrected translations and rotations. The efficacy of each correction was calculated as the overlap between the nodal-vessels structure in the reference and repeat CT scans. The motion magnitude between delineated structures was quantified using nonrigid registration. Translational corrections resulted in an average overlap of 58 ± 13% and in a range of motion between 9.9 and 27.3 mm. Translational and rotational corrections significantly improved the overlap (64 ± 13%, p value = 0.007) and moderately reduced the range of motion to 7.6-23.8 mm (p value = 0.03). Bladder filling changes significantly correlated with the nodal-vessels motion (p < 0.001). The motion of the nodal-vessels was large, nonrigid, patient-specific, and only moderately synchronous with the bony anatomy. This study highlights the need for caution when reducing the CTV-to-PTV (PTV planning target volume) margin of the nodal CTV for highly conformal radiation techniques. (orig.) [German] Bei Zervixkarzinompatientinnen wird davon ausgegangen, dass das nodale klinische Zielvolumen (CTV, definiert anhand der grossen Blutgefaesse des Beckens und vergroesserter Lymphknoten) sich synchron mit

  16. SU-F-I-40: Impact of Scan Length On Patient Dose in Abdomen/pelvis CT Diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Park, I; Song, J; Kim, K [Kyung Hee University, Yongin-si, Gyeonggi-do (Korea, Republic of)

    2016-06-15

    Purpose: To analysis the impact of scan length on patient doses in abdomen/pelvis CT diagnosis of each hospital. Methods: Scan length of 7 hospitals from abdomen/pelvis CT diagnosis was surveyed in Korea. Surveyed scan lengths were additional distance above diaphragm and distance below pubic symphysis except for standard scan range between diaphragm and pubic symphysis. Patient dose was estimated for adult male and female according to scan length of each hospital. CT-Expo was used to estimate the patient dose under identical equipment settings (120 kVp, 100 mAs, 10 mm collimation width, etc.) except scan length. Effective dose was calculated by using tissue weighting factor of ICRP 103 recommendation. Increase rate of effective dose was calculated comparing with effective dose of standard scan range Results: Scan lengths of abdomen/pelvis CT diagnosis of each hospital were different. Also effective dose was increased with increasing the scan length. Generally increasing the distance above diaphragm caused increase of effective dose of male and female, but increasing the distance below pubic symphysis caused increase of effective dose of male. Conclusion: We estimated the patient dose according to scan length of each hospital in abdomen/pelvis CT diagnosis. Effective dose was increased by increasing the scan length because dose of organs with high tissue weighting factor such as lung, breast, testis were increased. Scan length is important factor on patient dose in CT diagnosis. If radiologic technologist interested in patient dose, decreasing the unnecessary scan length will decrease the risk of patients from radiation. This research was supported by a grant of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (grant number: HI13C0004).

  17. Functional imaging in differentiating bronchial masses: an initial experience with a combination of (18)F-FDG PET-CT scan and (68)Ga DOTA-TOC PET-CT scan.

    Science.gov (United States)

    Kumar, Arvind; Jindal, Tarun; Dutta, Roman; Kumar, Rakesh

    2009-10-01

    To evaluate the role of combination of (18)F-FDG PET-CT scan and (68)Ga DOTA-TOC PET-CT scan in differentiating bronchial tumors observed in contrast enhanced computed tomography scan of chest. Prospective observational study. Place of study: All India Institute of Medical Sciences, New Delhi, India. 7 patients with bronchial mass detected in computed tomography scan of the chest were included in this study. All patients underwent (18)F-FDG PET-CT scan, (68)Ga DOTA-TOC PET-CT scan and fiberoptic bronchoscope guided biopsy followed by definitive surgical excision. The results of functional imaging studies were analyzed and the results are correlated with the final histopathology of the tumor. Histopathological examination of 7 bronchial masses revealed carcinoid tumors (2 typical, 1 atypical), inflammatory myofibroblastic tumor (1), mucoepidermoid carcinoma (1), hamartoma (1), and synovial cell sarcoma (1). The typical carcinoids had mild (18)F-FDG uptake and high (68)Ga DOTA-TOC uptake. Atypical carcinoid had moderate uptake of (18)F-FDG and high (68)Ga DOTA-TOC uptake. Inflammatory myofibroblastic tumor showed high uptake of (18)F-FDG and no uptake of (68)Ga DOTA-TOC. Mucoepidermoid carcinoma showed mild (18)F-FDG uptake and no (68)Ga DOTA-TOC uptake. Hamartoma showed no uptake on either scans. Synovial cell sarcoma showed moderate (18)F-FDG uptake and mild focal (68)Ga DOTA-TOC uptake. This initial experience with the combined use of (18)F-FDG and (68)Ga DOTA-TOC PET-CT scan reveals different uptake patterns in various bronchial tumors. Bronchoscopic biopsy will continue to be the gold standard; however, the interesting observations made in this study merits further evaluation of the utility of the combination of (18)F-FDG PET-CT scan and (68)Ga DOTA-TOC PET-CT scan in larger number of patients with bronchial masses.

  18. The use of CT-scan in foreign body aspiration in children: A 6 years' experience.

    Science.gov (United States)

    Pitiot, Vincent; Grall, Margaux; Ploin, Dominique; Truy, Eric; Ayari Khalfallah, Sonia

    2017-11-01

    A foreign body aspiration is a risky situation, common in pediatric emergency. The "gold standard" to rule out a foreign body or proceed to its extraction, is rigid bronchoscopy (RB) under general anesthesia. However, RB is an intrusive exam with possible complications. Depending on authors, RB in emergency is a procedure at risk of complications in 4-17% of cases. Advances in radiology allow CT-scanners of fast acquisition and high definition, which could be used as an alternative to RB. This is a retrospective analysis of 6 years from May 2010 to May 2016, in a tertiary referral center. All children that presented a foreign body aspiration suspicion and had a cervical-thoracic CT with multiplanar reconstruction were analyzed. 200 children were included. The average age was 30 months. 132 were considered normal and 68 pathological. Among the 68 RB performed for pathological scanner, a foreign body was found in 59 cases, and we had 9 cases of false positives. Among the 132 considered normal, 27 have had a RB despite this, due to persistent symptoms, all were negative; 105 were discharged home without endoscopy with monitoring instructions. 1 child was reviewed three months later for asthma, without second choking event reported. A new CT-scan found a foreign body that was removed by RB. Due to the nature of the foreign body it is very unlikely to link it to the first choking event, but retrospectively we cannot be certain. Considering this case as the only false negative, the negative predictive value (NPV) of CT was 99.2% and positive predictive value (PPV) of 83.8%. The use of CT -scan with multiplanar reconstruction in suspected foreign body aspiration is a reliable alternative to endoscopy under general anesthesia, especially in asymptomatic patients, avoiding too many negative endoscopies. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Opportunistic Osteoporosis Screening - Gleaning Additional Information from Diagnostic Wrist CT Scans.

    Science.gov (United States)

    Schreiber, Joseph J; Gausden, Elizabeth B; Anderson, Paul A; Carlson, Michelle G; Weiland, Andrew J

    2015-07-01

    Although screening for and treating osteoporosis can prevent subsequent fractures, the rates of such interventions are low following a distal radial fracture. One potential method for identifying metabolic bone disease is via Hounsfield unit (HU) measurements from diagnostic computed tomography (CT) scans. We hypothesized that HU values of the distal aspect of the radius could be used to assess local bone quality and would be predictive of distal radial fracture risk, thereby allowing the identification of patients in need of further management. Measurements of bone mineral density (BMD) were made for 100 patients on the basis of HU values of cancellous portions of the distal aspect of the radius, the ulnar head, and the capitate. The HU values in twenty-five male and twenty-five female patients with an acute distal radial fracture documented on CT were compared with those of age and sex-matched control patients who had a CT scan obtained for other indications. Among the control patients, HU values decreased as age increased. When assessed on the basis of sex, both male and female patients with a distal radial fracture had significantly lower regional BMD compared with nonfracture control patients. A distal radial HU value of 218 for females and 246 for males optimized sensitivity and specificity; values below this threshold were associated with an increased risk of distal radial fracture. HU measurements can be obtained from any diagnostic CT scan using modern software programs and can be obtained by physicians in the office setting with minimal effort and at no additional cost or radiation exposure to the patient. Regardless of imaging indications, we suggest that patients with HU values below the identified thresholds be considered for further metabolic bone disease work-up, such as additional imaging, laboratory assessments, the initiation of osteoporosis treatment, or appropriate referral. Copyright © 2015 by The Journal of Bone and Joint Surgery

  20. Normal SUV values measured from NaF18- PET/CT bone scan studies.

    Science.gov (United States)

    Win, Aung Zaw; Aparici, Carina Mari

    2014-01-01

    Cancer and metabolic bone diseases can alter the SUV. SUV values have never been measured from healthy skeletons in NaF18-PET/CT bone scans. The primary aim of this study was to measure the SUV values from normal skeletons in NaF18-PET/CT bone scans. A retrospective study was carried out involving NaF18- PET/CT bone scans that were done at our institution between January 2010 to May 2012. Our excluding criteria was patients with abnormal real function and patients with past history of cancer and metabolic bone diseases including but not limited to osteoporosis, osteopenia and Paget's disease. Eleven studies met all the criteria. The average normal SUVmax values from 11 patients were: cervical vertebrae 6.84 (range 4.38-8.64), thoracic vertebrae 7.36 (range 6.99-7.66), lumbar vertebrae 7.27 (range 7.04-7.72), femoral head 2.22 (range 1.1-4.3), humeral head 1.82 (range 1.2-2.9), mid sternum 5.51 (range 2.6-8.1), parietal bone 1.71 (range 1.3-2.4). According to our study, various skeletal sites have different normal SUV values. SUV values can be different between the normal bones and bones with tumor or metabolic bone disease. SUV can be used to quantify NaF-18 PET/CT studies. If the SUV values of the normal skeleton are known, they can be used in the characterization of bone lesions and in the assessment of treatment response to bone diseases.

  1. Normal SUV values measured from NaF18- PET/CT bone scan studies.

    Directory of Open Access Journals (Sweden)

    Aung Zaw Win

    Full Text Available Cancer and metabolic bone diseases can alter the SUV. SUV values have never been measured from healthy skeletons in NaF18-PET/CT bone scans. The primary aim of this study was to measure the SUV values from normal skeletons in NaF18-PET/CT bone scans.A retrospective study was carried out involving NaF18- PET/CT bone scans that were done at our institution between January 2010 to May 2012. Our excluding criteria was patients with abnormal real function and patients with past history of cancer and metabolic bone diseases including but not limited to osteoporosis, osteopenia and Paget's disease. Eleven studies met all the criteria.The average normal SUVmax values from 11 patients were: cervical vertebrae 6.84 (range 4.38-8.64, thoracic vertebrae 7.36 (range 6.99-7.66, lumbar vertebrae 7.27 (range 7.04-7.72, femoral head 2.22 (range 1.1-4.3, humeral head 1.82 (range 1.2-2.9, mid sternum 5.51 (range 2.6-8.1, parietal bone 1.71 (range 1.3-2.4.According to our study, various skeletal sites have different normal SUV values. SUV values can be different between the normal bones and bones with tumor or metabolic bone disease. SUV can be used to quantify NaF-18 PET/CT studies. If the SUV values of the normal skeleton are known, they can be used in the characterization of bone lesions and in the assessment of treatment response to bone diseases.

  2. Computer-assisted solid lung nodule 3D volumetry on CT : influence of scan mode and iterative reconstruction: a CT phantom study

    NARCIS (Netherlands)

    Coenen, Adriaan; Honda, Osamu; van der Jagt, Eric J.; Tomiyama, Noriyuki

    2013-01-01

    To evaluate the effect of high-resolution scan mode and iterative reconstruction on lung nodule 3D volumetry. Solid nodules with various sizes (5, 8, 10 and 12 mm) were placed inside a chest phantom. CT images were obtained with various tube currents, scan modes (conventional mode, high-resolution

  3. Traumatic brain injury: Comparison between autopsy and ante-mortem CT.

    Science.gov (United States)

    Panzer, Stephanie; Covaliov, Lidia; Augat, Peter; Peschel, Oliver

    2017-11-01

    The aim of this study was to compare pathological findings after traumatic brain injury between autopsy and ante-mortem computed tomography (CT). A second aim was to identify changes in these findings between the primary posttraumatic CT and the last follow-up CT before death. Through the collaboration between clinical radiology and forensic medicine, 45 patients with traumatic brain injury were investigated. These patients had undergone ante-mortem CT as well as autopsy. During autopsy, the brain was cut in fronto-parallel slices directly after removal without additional fixation or subsequent histology. Typical findings of traumatic brain injury were compared between autopsy and radiology. Additionally, these findings were compared between the primary CT and the last follow-up CT before death. The comparison between autopsy and radiology revealed a high specificity (≥80%) in most of the findings. Sensitivity and positive predictive value were high (≥80%) in almost half of the findings. Sixteen patients had undergone craniotomy with subsequent follow-up CT. Thirteen conservatively treated patients had undergone a follow-up CT. Comparison between the primary CT and the last ante-mortem CT revealed marked changes in the presence and absence of findings, especially in patients with severe traumatic brain injury requiring decompression craniotomy. The main pathological findings of traumatic brain injury were comparable between clinical ante-mortem CT examinations and autopsy. Comparison between the primary CT after trauma and the last ante-mortem CT revealed marked changes in the findings, especially in patients with severe traumatic brain injury. Hence, clinically routine ante-mortem CT should be included in the process of autopsy interpretation. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  4. On the prediction of X-ray dose deviations and the influence of CT scan protocols

    Science.gov (United States)

    Du Plessis, Freek CP

    2017-09-01

    Patients undergoing computerized tomography (CT) scans for tumor localization and treatment planning are frequently scanned using pre-set customized exposure protocols for optimal imaging of different anatomical sites. The question arises if these scanning protocols will produce a deviation in the Hounsfield number for a given tissue that can afterwards be used to predict the resulting dose calculation deviation due to this. The question is also if the deviation in the Hounsfield number of a tissue is large enough to affect dose calculation clinically significant. A study was devised in which a RMI phantom was scanned with five different scanning protocols and two CT beam energies at 120 and 135 kV. To assess the effect of insert configuration, Hounsfield number measurements were repeated for high density RMI inserts in the center and outer rings in the phantom. For each material insert the standard deviation of the Hounsfield number was calculated. To assist in dose prediction a series of DOSXYZnrc Monte Carlo calculations were carried out for beam qualities between 6 and 16 MV for a range of Hounsfield numbers calculated for bone and water. This provided information on how the depth dose varied as a function of Hounsfield number variation. Lastly, a series of treatment plans were setup for absorbed dose calculation using the RMI insert electron densities vs Hounsfield relations measured above. The absorbed dose of corresponding plans with the largest Hounsfield number variation were subtracted to find the dose discrepancies. It was found that the dose discrepancies in tissue types could be indicated by the deviation of the Hounsfield number due to different scanning protocols. The calculated dose difference were in all cases within 3%.

  5. Estimation of absorbed dose of radiosensitive organs and effective sose in patients underwent abdominopelvic spiral CT scan using impact CT patient dosimetry

    Directory of Open Access Journals (Sweden)

    Ayoub Amirnia

    2017-05-01

    Full Text Available Background: Due to the presence of radiosensitive organs in the abdominopelvic region and increasing the number of requests for CT scan examinations, concerns about increasing radiation doses in patients has been greatly elevated. Therefore, the goal of this study was to determine the absorbed dose of radiosensitive organs and the effective dose in patients underwent abdominopelvic CT scan using ImPACT CT patient dosimetry Calculator (version 1.0.4, Imaging Performance Assessment on Computed Tomography, www.impactscan.org. Methods: This prospective cross-sectional study was conducted in Imam Reza Hospital from November to February 2015 February 2015 in the Imam Reza Hospital, in Urmia, Iran. The demographic and dosimetric information of 100 patients who underwent abdominopelvic CT scan in a 6-slice CT scanner were obtained through the data collection forms. The demographic data of the patients included age, weight, gender, and BMI. The dosimetric parameters included pitch value, CT dose volume index (CTDIvol, dose-length product (DLP, tube voltage, tube current, exposure time, collimation size, scan length, and scan time. To determine the absorbed dose of radiosensitive organs and also the effective dose in patients, ImPACT CT patient dosimetry calculator was used. Results: The results of this study demonstrated that the mean and standard deviation (SD of patients' effective dose in abdominopelvic CT scan was 4.927±0.164 mSv. The bladder in both genders had the greatest mean organ dose, which was 64.71±17.15 mGy for men and 77.56±18.48 mGy for women (P<0.001. Conclusion: The effective dose values of this examination are in the same range as previous studies, as well as International Commission on Radiological Protection (ICRP recommendations. However, the radiation dose from CT scan has the largest contribution to the medical imaging. According to the ALARA principle, it is recommended that the scan parameters, especially mAs, should be

  6. Detection of bladder cancer: comparison of low-dose scans with AIDR 3D and routine-dose scans with FBP on the excretory phase in CT urography.

    Science.gov (United States)

    Juri, Hiroshi; Tsuboyama, Takahiro; Kumano, Seishi; Inada, Yuki; Koyama, Mitsuhiro; Azuma, Haruhito; Narumi, Yoshifumi

    2016-01-01

    To prospectively compare the detection of bladder cancer between low-dose scans with adaptive iterative dose reduction three dimensional projection (AIDR 3D) and routine-dose scans with filtered back projection (FBP) on the excretory phase (EP) in CT urography. 42 patients were included. Routine- and low-dose EP were performed in each patient. Routine-dose images were reconstructed with FBP, and low-dose images were reconstructed with AIDR 3D. Two radiologists scored confidence levels for the presence or absence of bladder cancer using a 5-point scale. The CT dose index of each EP was measured, and the dose reduction was calculated. Sensitivity, specificity and accuracy were 86.4%, 95.0% and 90.5% on routine-dose scans and were 86.4%, 90.0% and 88.1% on low-dose scans, respectively. There was no significant difference (p; not significant, 1.00 and 1.00, respectively). The average CT dose index was 8.07 and 2.63 mGy on routine- and low-dose scans, and the ratio of dose reduction was 67.6%. The detection of bladder cancer on low-dose scans with AIDR 3D is almost equal to that on routine-dose scans with FBP on the EP, with nearly 70% dose reduction. Using AIDR 3D, the radiation dose may be reduced on the EP in CT urography for the detection of bladder cancer.

  7. SU-F-I-31: Reproducibility of An Automatic Exposure Control Technique in the Low-Dose CT Scan of Cardiac PET/CT Exams

    Energy Technology Data Exchange (ETDEWEB)

    Park, M; Rosica, D; Agarwal, V; Di Carli, M; Dorbala, S [Brigham and Women’s Hospital and Harvard Medical School, Boston, MA (United States)

    2016-06-15

    Purpose: Two separate low-dose CT scans are usually performed for attenuation correction of rest and stress N-13 ammonia PET/CT myocardial perfusion imaging (PET/CT). We utilize an automatic exposure control (AEC) technique to reduce CT radiation dose while maintaining perfusion image quality. Our goal is to assess the reproducibility of displayed CT dose index (CTDI) on same-day repeat CT scans (CT1 and CT2). Methods: Retrospectively, we reviewed CT images of PET/CT studies performed on the same day. Low-dose CT utilized AEC technique based on tube current modulation called Smart-mA. The scan parameters were 64 × 0.625mm collimation, 5mm slice thickness, 0.984 pitch, 1-sec rotation time, 120 kVp, and noise index 50 with a range of 10–200 mA. The scan length matched with PET field of view (FOV) with the heart near the middle of axial FOV. We identified the reference slice number (RS) for an anatomical landmark (carina) and used it to estimate axial shift between two CTs. For patient size, we measured an effective diameter on the reference slice. The effect of patient positioning to CTDI was evaluated using the table height. We calculated the absolute percent difference of the CTDI (%diff) for estimation of the reproducibility. Results: The study included 168 adults with an average body-mass index of 31.72 ± 9.10 (kg/m{sup 2}) and effective diameter was 32.72 ± 4.60 cm. The average CTDI was 1.95 ± 1.40 mGy for CT1 and 1.97 ± 1.42mGy for CT2. The mean %diff was 7.8 ± 6.8%. Linear regression analysis showed a significant correlation between the table height and %diff CTDI. (r=0.82, p<0.001) Conclusion: We have shown for the first time in human subjects, using two same-day CT images, that the AEC technique in low-dose CT is reproducible within 10% and significantly depends on the patient centering.

  8. [Lung cancer screening with low-dose thoracic CT-scan in the Somme area].

    Science.gov (United States)

    Leleu, O; Auquier, M; Carre, O; Chauffert, B; Dubreuil, A; Petigny, V; Trancart, B; Berna, P; Jounieaux, V

    2017-03-01

    This feasibility trial proposes to set up in the department of the Somme an annual screening for lung cancer with low-dose thoracic CT. It responds to the first objective of the third cancer plan and follows the publication of the results of the National Lung Screening Trial in 2011. The method of this study is to use the existing networks among and between healthcare professionals and the departmental cancer screening structure. The inclusion criteria will be those of the National Lung Screening Trial. Screening will be proposed by treating physicians and chest physicians. The CT-scan will be performed in radiological centers that adhere to the good practice charter for low radiation scanning. A copy of CT results will be sent to the departmental structure of cancer screening (ADEMA80) which will ensure traceability and will perform statistical analysis. The study received funding from the Agence régionale de santé de la Picardie and la ligue contre le cancer. The primary endpoints of this screening will be the number of cancers diagnosed and the survival of the patients. The follow-up of positive examinations, delays in management and the level of participation will also be assessed. Copyright © 2016 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  9. Traumatic cervical spinal cord injury with "negative" cervical spine CT scan.

    Science.gov (United States)

    Kolli, Sreedhar; Schreiber, Adam; Harrop, James; Jallo, Jack

    2010-01-01

    A 46-year-old man fell four steps, striking his neck and having associated neck pain and discomfort. He was evaluated at a local emergency department and reported no neurological deficit but focal mid cervical tenderness. Radiographs and computed tomography (CT) scan were "negative" for cervical spine fracture, dislocation or pre-vertebral soft tissue swelling. He was discharged home in a cervical collar with a scheduled outpatient follow-up. Over the proceeding hours neurologic deterioration occurred, including hand and lower limb weakness with the inability to urinate. The patient returned to the local emergency room and was transferred to a tertiary care hospital where examination revealed C5ASIAB deficits. Repeat high resolution CT scan of the cervical spine with reformatted images was unremarkable for osseous fractures except some loss of definition in the posterior cervical musculature. Emergency magnetic resonance imaging MRI revealed a subluxation of C5/6 right facet (not evident on CT) with disruption of the posterior longitudinal ligament, ligamentum flavum, and disc space with abnormal T2 weighted spinal cord hyperintense signal at C5/6. He underwent emergency C5-C6 anterior and posterior decompression and fusion. One week later an examination showed improved C5ASIAD. This case reveals the difficulty of assessing the cervical spine for instability and potential limitations of current management schemes.

  10. Optical CT scanning of cross-linked radiochromic gel without cylinder wall

    Energy Technology Data Exchange (ETDEWEB)

    Jordan, Kevin [London Regional Cancer Program, London Health Sciences Centre and Department of Medical Biophysics, University of Western Ontario, London, ON (Canada)], E-mail: kevin.jordan@lhsc.on.ca

    2009-05-01

    Genipin cross-linked gelatin hydrogels with 0.2 M sulphuric acid are radiochromic and have sufficient sensitivity for investigating doses less than 50 Gray. Because of the gelatine cross-links, these gels have sufficient strength to allow removal from the vessel container in which they were cast. Placing the gels in the same liquid that was used for preparing the gel allows the radiochemistry to the same throughout the gels and provides physical support. In this buoyancy neutral environment the gel has the same shape and the preparation vessel. This allows optical CT scanning without wall artefacts due to reflection, refraction and optical activity. A gel was irradiated to dose of 25 Gray with a 10 MV photon beam of 20 x 20 mm cross section. Full 3D optical CT scanning was performed with a Vista 10 optical cone-beam CT scanner. Central beam axis profiles and depth dose agree with diode and parallel plate ion chamber measurements. These results demonstrate that genipin cross-linked gel can be used for accurate 3D dosimetry, including surface dose measurements.

  11. Male and Female Human Body Tissue Radiation Shielding Models Based upon CT-scan Data for Organ Dose Prediction

    Science.gov (United States)

    Qualls, G.; Nealy, J.; Wilson, J.; Cucinotta, F.

    As present and future human space mission lengths are extended, it becomes increasingly important and valuable to have accurate analytic predictions of radiation doses to specific tissues within the body. New computational models are being developed to help predict the effective radiation shielding to points inside the human body provided by the surrounding body tissue. A female body tissue model, based upon a full-body CT-scan from the Visible Human Project, is presented along with a male body tissue model based upon a full-body CT-scan data set obtained from Johns Hopkins University. The advantages of using CT-scan based models are presented along with initial results and comparisons to previous models. Details of the data processing required to transform a raw CT-scan into a tissue shielding model are also presented.

  12. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... therapy for brain cancer. In emergency cases, it can reveal internal injuries and bleeding quickly enough to ... cross-sectional images generated during a CT scan can be reformatted in multiple planes, and can even ...

  13. Reduction of Cone-Beam CT scan time without compromising the accuracy of the image registration in IGRT

    DEFF Research Database (Denmark)

    Westberg, Jonas; Jensen, Henrik R; Bertelsen, Anders

    2010-01-01

    In modern radiotherapy accelerators are equipped with 3D cone-beam CT (CBCT) which is used to verify patient position before treatment. The verification is based on an image registration between the CBCT acquired just before treatment and the CT scan made for the treatment planning. The purpose...

  14. Optimization of Parameters in 16-slice CT-‌‌scan Protocols for Reduction of the Absorbed Dose

    Directory of Open Access Journals (Sweden)

    Shahrokh Naseri

    2014-08-01

    Full Text Available Introduction In computed tomography (CT technology, an optimal radiation dose can be achieved via changing radiation parameters such as mA, pitch factor, rotation time and tube voltage (kVp for diagnostic images. Materials and Methods In this study, the brain, abdomen, and thorax scaning was performed using Toshiba 16-slice scannerand standard AAPM and CTDI phantoms. AAPM phantom was used for the measurement of image-related parameters and CTDI phantom was utilized for the calculation of absorbed dose to patients. Imaging parameters including mA (50-400 mA, pitch factor (1 and 1.5 and rotation time (range of 0.5, 0.75, 1, 1.5 and 2 seconds were considered as independent variables. The brain, abdomen and chest imaging was performed multi-slice and spiral modes. Changes in image quality parameters including contrast resolution (CR and spatial resolution (SR in each condition were measured and determined by MATLAB software. Results After normalizing data by plotting the full width at half maximum (FWHM of point spread function (PSF in each condition, it was observed that image quality was not noticeably affected by each cases. Therefore, in brain scan, the lowest patient dose was in 150 mA and rotation time of 1.5 seconds. Based on results of scanning of the abdomen and chest, the lowest patient dose was obtained by 100 mA and pitch factors of 1 and 1.5. Conclusion It was found that images with acceptable quality and reliable detection ability could be obtained using smaller doses of radiation, compared to protocols commonly used by operators.

  15. Ameloblastic Fibro-odontoma Case Report: Diagnostic Valuable Aid of CT Scan in Identification of Mineralized Component

    Directory of Open Access Journals (Sweden)

    Devi Charan Shetty

    2010-01-01

    Full Text Available Many lesions that occur in the jaw have a similar radiographical appearance and it is often difficult to differentiate among them. Despite development of various cross-sectional imaging modalities the radiograph still remains the first and the most important investigation. Radiographical evaluation of jaw lesion characteristics, which include location, margin, density, relation to tooth, along with knowledge of the clinical data, generally helps in narrowing the diagnosis. With advancing technology today the mutti-row scanners are used for an increasing number of indications for routine examinations. Most major research facilities use 64-slice scanners on a routine clinical basis. Computed tomography (CT scans are not ideal for imaging soft tissues such as muscles, joints or brain, but are perfect for detecting air or calcium. CT provides very good spatial resolution, that is the ability to distinguish between two separate structures that are very close together. But precision in identifying these calcified structures could be upregulated by the use of this normal routine specialized technique along with a software, which uses in its principle methods to quantity and qualitate the density.

  16. Automated ventricular systems segmentation in brain CT images by combining low-level segmentation and high-level template matching

    Directory of Open Access Journals (Sweden)

    Ward Kevin R

    2009-11-01

    Full Text Available Abstract Background Accurate analysis of CT brain scans is vital for diagnosis and treatment of Traumatic Brain Injuries (TBI. Automatic processing of these CT brain scans could speed up the decision making process, lower the cost of healthcare, and reduce the chance of human error. In this paper, we focus on automatic processing of CT brain images to segment and identify the ventricular systems. The segmentation of ventricles provides quantitative measures on the changes of ventricles in the brain that form vital diagnosis information. Methods First all CT slices are aligned by detecting the ideal midlines in all images. The initial estimation of the ideal midline of the brain is found based on skull symmetry and then the initial estimate is further refined using detected anatomical features. Then a two-step method is used for ventricle segmentation. First a low-level segmentation on each pixel is applied on the CT images. For this step, both Iterated Conditional Mode (ICM and Maximum A Posteriori Spatial Probability (MASP are evaluated and compared. The second step applies template matching algorithm to identify objects in the initial low-level segmentation as ventricles. Experiments for ventricle segmentation are conducted using a relatively large CT dataset containing mild and severe TBI cases. Results Experiments show that the acceptable rate of the ideal midline detection is over 95%. Two measurements are defined to evaluate ventricle recognition results. The first measure is a sensitivity-like measure and the second is a false positive-like measure. For the first measurement, the rate is 100% indicating that all ventricles are identified in all slices. The false positives-like measurement is 8.59%. We also point out the similarities and differences between ICM and MASP algorithms through both mathematically relationships and segmentation results on CT images. Conclusion The experiments show the reliability of the proposed algorithms. The

  17. Automated ventricular systems segmentation in brain CT images by combining low-level segmentation and high-level template matching.

    Science.gov (United States)

    Chen, Wenan; Smith, Rebecca; Ji, Soo-Yeon; Ward, Kevin R; Najarian, Kayvan

    2009-11-03

    Accurate analysis of CT brain scans is vital for diagnosis and treatment of Traumatic Brain Injuries (TBI). Automatic processing of these CT brain scans could speed up the decision making process, lower the cost of healthcare, and reduce the chance of human error. In this paper, we focus on automatic processing of CT brain images to segment and identify the ventricular systems. The segmentation of ventricles provides quantitative measures on the changes of ventricles in the brain that form vital diagnosis information. First all CT slices are aligned by detecting the ideal midlines in all images. The initial estimation of the ideal midline of the brain is found based on skull symmetry and then the initial estimate is further refined using detected anatomical features. Then a two-step method is used for ventricle segmentation. First a low-level segmentation on each pixel is applied on the CT images. For this step, both Iterated Conditional Mode (ICM) and Maximum A Posteriori Spatial Probability (MASP) are evaluated and compared. The second step applies template matching algorithm to identify objects in the initial low-level segmentation as ventricles. Experiments for ventricle segmentation are conducted using a relatively large CT dataset containing mild and severe TBI cases. Experiments show that the acceptable rate of the ideal midline detection is over 95%. Two measurements are defined to evaluate ventricle recognition results. The first measure is a sensitivity-like measure and the second is a false positive-like measure. For the first measurement, the rate is 100% indicating that all ventricles are identified in all slices. The false positives-like measurement is 8.59%. We also point out the similarities and differences between ICM and MASP algorithms through both mathematically relationships and segmentation results on CT images. The experiments show the reliability of the proposed algorithms. The novelty of the proposed method lies in its incorporation of

  18. Digital forensic osteology: morphological sexing of skeletal remains using volume-rendered cranial CT scans.

    Science.gov (United States)

    Ramsthaler, Frank; Kettner, Mattias; Gehl, Axel; Verhoff, M A

    2010-02-25

    Because of the increasing lack of recent bone collections, ethical issues concerning maceration procedures, and progress in radiological imaging techniques, computed tomography (CT) scans offer an alternative to traditional anthropological bone collection. The present study examined volume-rendered cranial CT (CCT) scans from 50 crania to morphologically evaluate sex characteristics. CCT scans were performed and scored by two teams (Teams A and B) of two examiners each (2x50=100 examinations) to evaluate the occurrence and/or absence of morphological traits. Altogether, 60 of 100 crania (31 Team A+29 Team B) crania were determined to be male, and 40 (19 Team A+21 Team B) were determined to be female when using the scoring system adapted from Knussmann. These results imply a sex determination accuracy rate of 96%. Only in one case was recalculation of weighting factors necessary to determine one additional correct classification. As a single parameter, arcus superciliaris evaluation permitted the most accurate sex determination (female, 84.2%; male, 85.5%). No significant difference in accuracy rates was observed between the two sexes (pforensic casework and the systematic reevaluation and improvement of classical anthropological methods and their adaptation to changing populations. 2010 Elsevier Ireland Ltd. All rights reserved.

  19. Automated Detection of Healthy and Diseased Aortae from Images Obtained by Contrast-Enhanced CT Scan

    Directory of Open Access Journals (Sweden)

    Michael Gayhart

    2013-01-01

    Full Text Available Purpose. We developed the next stage of our computer assisted diagnosis (CAD system to aid radiologists in evaluating CT images for aortic disease by removing innocuous images and highlighting signs of aortic disease. Materials and Methods. Segmented data of patient’s contrast-enhanced CT scan was analyzed for aortic dissection and penetrating aortic ulcer (PAU. Aortic dissection was detected by checking for an abnormal shape of the aorta using edge oriented methods. PAU was recognized through abnormally high intensities with interest point operators. Results. The aortic dissection detection process had a sensitivity of 0.8218 and a specificity of 0.9907. The PAU detection process scored a sensitivity of 0.7587 and a specificity of 0.9700. Conclusion. The aortic dissection detection process and the PAU detection process were successful in removing innocuous images, but additional methods are necessary for improving recognition of images with aortic disease.

  20. A multicenter, randomized controlled trial of immediate total-body CT scanning in trauma patients (REACT-2

    Directory of Open Access Journals (Sweden)

    Sierink Joanne C

    2012-03-01

    Full Text Available Abstract Background Computed tomography (CT scanning has become essential in the early diagnostic phase of trauma care because of its high diagnostic accuracy. The introduction of multi-slice CT scanners and infrastructural improvements made total-body CT scanning technically feasible and its usage is currently becoming common practice in several trauma centers. However, literature provides limited evidence whether immediate total-body CT leads to better clinical outcome then conventional radiographic imaging supplemented with selective CT scanning in trauma patients. The aim of the REACT-2 trial is to determine the value of immediate total-body CT scanning in trauma patients. Methods/design The REACT-2 trial is an international, multicenter randomized clinical trial. All participating trauma centers have a multi-slice CT scanner located in the trauma room or at the Emergency Department (ED. All adult, non-pregnant, severely injured trauma patients according to predefined criteria will be included. Patients in whom direct scanning will hamper necessary cardiopulmonary resuscitation or who require an immediate operation because of imminent death (both as judged by the trauma team leader are excluded. Randomization will be computer assisted. The intervention group will receive a contrast-enhanced total-body CT scan (head to pelvis during the primary survey. The control group will be evaluated according to local conventional trauma imaging protocols (based on ATLS guidelines supplemented with selective CT scanning. Primary outcome will be in-hospital mortality. Secondary outcomes are differences in mortality and morbidity during the first year post trauma, several trauma work-up time intervals, radiation exposure, general health and quality of life at 6 and 12 months post trauma and cost-effectiveness. Discussion The REACT-2 trial is a multicenter randomized clinical trial that will provide evidence on the value of immediate total-body CT scanning

  1. Optic nerve sheath diameter measurements by CT scan in ventriculoperitoneal shunt obstruction.

    Science.gov (United States)

    Zaidi, Syed Javed H; Yamamoto, Loren G

    2014-08-01

    The objective of the study was to determine differences in optic nerve sheath diameter (ONSD) measurements taken from computed tomography (CT) scans of patients with ventriculoperitoneal shunt (VPS) obstruction versus controls. Inpatients 0-15 years with confirmed VPS obstruction requiring neurosurgical intervention were identified using ICD9 codes. ONSDs, orbit, cranium, and foramen magnum sizes were measured on their pre-surgical CT. Controls included cases at times when their VPS was not obstructed and age and gender matched patients with a CT scan done in the emergency room for head trauma (normal CT findings). Paired T-tests were used for both case-control comparisons. In order to compare the optic nerve sheath size more accurately, the ONSD width was divided by the width of the orbit and by the foramen magnum (antero-posterior) length. Twenty patients were identified with 25 events of VPS obstruction. The right ONSD (RON) was chosen to study. RON/orbit width and RON/foramen magnum diameter for the VPS obstruction versus self-controls, were 0.22 and 0.22, compared to 0.19 and 0.18, respectively, for the non-obstructed self-controls (P = .044 and P = .008, respectively). The same measurements for the VPS obstruction versus age and gender matched controls were 0.22 and 0.21 for the VPS obstruction cases, respectively, compared to 0.17 and 0.16, respectively for the age and gender matched controls (P VPS obstruction. ONSD measurements by ultrasound could add to the evaluation for VPS obstruction.

  2. Semi-automated method to measure pneumonia severity in mice through computed tomography (CT) scan analysis

    Science.gov (United States)

    Johri, Ansh; Schimel, Daniel; Noguchi, Audrey; Hsu, Lewis L.

    2010-03-01

    Imaging is a crucial clinical tool for diagnosis and assessment of pneumonia, but quantitative methods are lacking. Micro-computed tomography (micro CT), designed for lab animals, provides opportunities for non-invasive radiographic endpoints for pneumonia studies. HYPOTHESIS: In vivo micro CT scans of mice with early bacterial pneumonia can be scored quantitatively by semiautomated imaging methods, with good reproducibility and correlation with bacterial dose inoculated, pneumonia survival outcome, and radiologists' scores. METHODS: Healthy mice had intratracheal inoculation of E. coli bacteria (n=24) or saline control (n=11). In vivo micro CT scans were performed 24 hours later with microCAT II (Siemens). Two independent radiologists scored the extent of airspace abnormality, on a scale of 0 (normal) to 24 (completely abnormal). Using the Amira 5.2 software (Mercury Computer Systems), a histogram distribution of voxel counts between the Hounsfield range of -510 to 0 was created and analyzed, and a segmentation procedure was devised. RESULTS: A t-test was performed to determine whether there was a significant difference in the mean voxel value of each mouse in the three experimental groups: Saline Survivors, Pneumonia Survivors, and Pneumonia Non-survivors. It was found that the voxel count method was able to statistically tell apart the Saline Survivors from the Pneumonia Survivors, the Saline Survivors from the Pneumonia Non-survivors, but not the Pneumonia Survivors vs. Pneumonia Non-survivors. The segmentation method, however, was successfully able to distinguish the two Pneumonia groups. CONCLUSION: We have pilot-tested an evaluation of early pneumonia in mice using micro CT and a semi-automated method for lung segmentation and scoring system. Statistical analysis indicates that the system is reliable and merits further evaluation.

  3. Improved image quality and radiation dose reduction in liver dynamic CT scan with the protocol change

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Yu Jin; Cho, Pyong Kon [Radiological Science, Catholic University of Daegu, Daegu (Korea, Republic of)

    2015-06-15

    The purpose is reducing radiation dose while maintaining of image quality in liver dynamic CT(LDCT) scan, by protocols generally used and the tube voltage set at a low level protocol compared to the radiation dose and image quality. The target is body mass index, 18.5-24 patients out of 40 patients who underwent the ACT(abdominal CT). Group A(tube voltage : 120 kVp, SAFIRE strength 1) of 20 people among 40 people, to apply the general abdominal CT scan protocol, group B(tube voltage : 100 kVp, apply SAFIRE strength 0-5) was 20 people, set a lower tube voltage. Image quality evaluation was setting a region of interest(ROI) in the liver parenchyma, aorta, superior mesenteric artery (SMA), celiac trunk, visceral fat of arterial phase. In the ROI were compared by measuring the noise, signal to noise ratio(SNR), contrast to noise ratio(CNR), CT number. In addition, qualitative assessments to evaluate two people in the rich professional experience in Radiology by 0-3 points. We compared the total radiation dose, dose length product(DLP) and effective dose, volume computed tomography dose index(CTDIvol). The higher SAFIRE in the tube voltage 100 kVp, noise is reduced, CT number was increased. Thus, SNR and CNR was increased higher the SAFIRE step. Compared with the tube voltage 120 kVp, noise, SNR, CNR was most similar in SAFIRE strength 2 and 3. Qualitative assessment SAFIRE strength 2 is the most common SAFIRE strength 2 the most common qualitative assessment, if the tube voltage of 100 kVp when the quality of the images better evaluated was SAFIRE strength 1. Dose was reduced from 21.69%, in 100 kVp than 120 kVp. In the case of a relatively high BMI is not LDCT scan, When it is shipped from the factory tube voltage is set higher, unnecessary radiation exposure when considering the reality that is concerned, when according to the results of this study, set a lower tube voltage and adjust the SAFIRE strength to 1 or 2, the radiation without compromising image quality

  4. Quantitative assessment of emphysema from whole lung CT scans: comparison with visual grading

    Science.gov (United States)

    Keller, Brad M.; Reeves, Anthony P.; Apanosovich, Tatiyana V.; Wang, Jianwei; Yankelevitz, David F.; Henschke, Claudia I.

    2009-02-01

    Emphysema is a disease of the lungs that destroys the alveolar air sacs and induces long-term respiratory dysfunction. CT scans allow for imaging of the anatomical basis of emphysema and for visual assessment by radiologists of the extent present in the lungs. Several measures have been introduced for the quantification of the extent of disease directly from CT data in order to add to the qualitative assessments made by radiologists. In this paper we compare emphysema index, mean lung density, histogram percentiles, and the fractal dimension to visual grade in order to evaluate the predictability of radiologist visual scoring of emphysema from low-dose CT scans through quantitative scores, in order to determine which measures can be useful as surrogates for visual assessment. All measures were computed over nine divisions of the lung field (whole lung, individual lungs, and upper/middle/lower thirds of each lung) for each of 148 low-dose, whole lung scans. In addition, a visual grade of each section was also given by an expert radiologist. One-way ANOVA and multinomial logistic regression were used to determine the ability of the measures to predict visual grade from quantitative score. We found that all measures were able to distinguish between normal and severe grades (p<0.01), and between mild/moderate and all other grades (p<0.05). However, no measure was able to distinguish between mild and moderate cases. Approximately 65% prediction accuracy was achieved from using quantitative score to predict visual grade, with 73% if mild and moderate cases are considered as a single class.

  5. Determining the lymphadenopathy characteristics of the mediastinum in lung CT scan of children with tuberculosis.

    Science.gov (United States)

    Mehrian, Payam; Moghaddam, Amin Momeni; Tavakkol, Elham; Amini, Afshin; Moghimi, Mehrdad; Kabir, Ali; Velayati, Aliakbar

    2016-09-01

    Most tuberculosis cases in children are primary infection, with difficult and imprecise diagnosis mainly based on the existence of mediastinal lymphadenopathy. Here, we investigated the characteristics of mediastinal lymphadenopathy in lung computed tomography (CT) scans of children with tuberculosis. This cross-sectional study was performed on 75 children with tuberculosis referred to Masih Daneshvari Hospital in Tehran, Iran, from 2009 to 2013. Their medical records were investigated, and CT-scan characteristics were extracted by a radiologist. Mean±standard deviation age of cases was 11.2±4.6years. CT-scan results indicated 94.7% of cases had lymphadenopathy, with lower paratracheal, upper paratracheal, hilar, and subcarinal forms observed in 81.7%, 69.1%, 53.5%, and 47.9% of cases as the most involved stations in lymph nodes, respectively. In 74.6% of patients with mediastinal lymphadenopathy, perilymph node fat inflammation (matting) was observed, with 52.11% exhibiting conglomeration. Bronchial pressure was observed in 4.23% of children with tuberculosis, and bilateral-, right-, and left-parenchymal involvement was observed in 42.7%, 25.3%, and 8% of these cases, respectively. Left- and right-pleural effusion and calcification was reported in 6.7%, 12%, and 5.6% of patients, respectively. Additionally, nearly 80% of patients exhibited mediastinal lymphadenopathy and lung-parenchyma involvement simultaneously. Lung-parenchyma involvement was significantly correlated with subcarinal (p<.001), hilar (p<.001), subaortic (p=.030), lower paratracheal (p=.037), and axillary (p=.006) stations. Situation of mediastinal lymphadenopathy and its synchronicity with lung-parenchyma involvement can help in differential diagnosis of pulmonary tuberculosis from other lung diseases. Copyright © 2016 Asian-African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.

  6. Identification of intra-hepatic communicating veins through the arch sign on CT-scan.

    Science.gov (United States)

    Morel, Alexandre; Rivoire, Michel; Basso, Valéria; Meeus, Pierre; Peyrat, Patrice; Dupré, Aurélien

    2017-06-01

    Knowledge of vascular outflow is essential in liver surgery. Communicating veins between the right hepatic vein (RHV) and the middle hepatic vein (MHV) have been described and allowed us to perform new surgical procedures. The aim of this study was to predict the existence of intra-hepatic venous anastomosis by identifying communicating veins on 2D CT-scan imaging. We retrospectively analysed data from 32 patients operated on for liver tumours between 2004 and 2013 who underwent a bisegmentectomy VI-VII enlarged to the RHV and/or a bisegmentectomy VII-VIII and/or a left hepatectomy enlarged to the MHV and who had pre and post-operative CT-scans. Patients with cirrhosis were excluded. We first analysed post-operative images and, in patients with a proven collateral vein, looked for evidence of this on pre-operative imaging. We then validated this pre-operative sign against post-operative imaging. Collaterals from both the RHV and the MHV formed an arch visible on pre-operative imaging which predicted the development of intrahepatic venous anastomosis in 20 patients. In 14 patients, a perfect match between the arch sign and development of collaterals was observed (n = 28). Sensitivity, specificity, negative and positive predictive values were 87, 80, 80, and 87%, respectively. Positive and negative likelihood ratio tests were 4.3 and 0.16, respectively. Communicating veins between the RHV and the MHV are frequent and can be predicted by the arch sign on 2D CT-scan. Hence the arch sign can be very useful when planning liver surgery.

  7. CT scan-based modelling of anastomotic leak risk after colorectal surgery.

    Science.gov (United States)

    Gervaz, P; Platon, A; Buchs, N C; Rocher, T; Perneger, T; Poletti, P-A

    2013-01-01

    Prolonged ileus, low-grade fever and abdominal discomfort are common during the first week after colonic resection. Undiagnosed anastomotic leak carries a poor outcome and computed tomography (CT) scan is the best imaging tool for assessing postoperative abdominal complications. We used a CT scan-based model to quantify the risk of anastomotic leak after colorectal surgery. A case-control analysis of 74 patients who underwent clinico-radiological evaluation after colorectal surgery for suspicion of anastomotic leak was undertaken and a multivariable analysis of risk factors for leak was performed. A logistic regression model was used to identify determinant variables and construct a predictive score. Out of 74 patients with a clinical suspicion of anastomotic leak, 17 (23%) had this complication confirmed following repeat laparotomy. In multivariate analysis, three variables were associated with anastomotic leak: (1) white blood cells count > 9 × 10(9) /l (OR = 14.8); (2) presence of ≥ 500 cm(3) of intra- abdominal fluid (OR = 13.4); and (3) pneumoperitoneum at the site of anastomosis (OR = 9.9). Each of these three parameters contributed one point to the risk score. The observed risk of leak was 0, 6, 31 and 100%, respectively, for patients with scores of 0, 1, 2 and 3. The area under the receiver operating characteristic curve for the score was 0.83 (0.72-0.94). This CT scan-based model seems clinically promising for objective quantification of the risk of a leak after colorectal surgery. Colorectal Disease © 2013 The Association of Coloproctology of Great Britain and Ireland.

  8. Metastatic Male Breast Cancer With Increased Uptake on 18F-Fluciclovine PET/CT Scan.

    Science.gov (United States)

    Gill, Harkanwar S; Tade, Funmilayo; Greenwald, David Theodore; Yonover, Paul M; Savir-Baruch, Bital

    2018-01-01

    Prostate imaging with F-labeled 1-amino-3-fluorocyclobutane-1-carboxylic acid (FACBC, F-fluciclovine) PET/CT scan (Axumin) was recently approved by the US Food and Drug Administration for men with suspected prostate cancer recurrence based on elevated blood prostate-specific antigen levels following prior treatment. We present a rare case of a 77-year-old man with suspected recurrent prostate cancer with an incidental finding of advanced-stage breast cancer showing different degrees of F-fluciclovine uptake.

  9. Evaluation of Clinical Contributions Provided by Addition of the Brain, Calvarium, and Scalp to the Limited Whole Body Imaging Area in FDG-PET/CT Tumor Imaging

    Directory of Open Access Journals (Sweden)

    Bekir Tasdemir

    2014-01-01

    Full Text Available Purpose. The aim of this study was to detect additional findings in whole body FDG-PET/CT scan including the brain, calvarium, and scalp (compared to starting from the base of the skull in cancer patients and to determine contributions of these results to tumor staging and treatment protocols. Materials and Methods. We noted whether the findings related to the brain, calvarium, and scalp in 1359 patients had a potential to modify staging of the disease, chemotherapy protocol, radiotherapy protocol, and surgical management. We identified rates of metastatic findings on the brain, calvarium, and scalp according to the tumor types on FDG-PET/CT scanning. Results. We found FDG-PET/CT findings for malignancy above the base of the skull in 42 patients (3.1%, one of whom was a patient with an unknown primary tumor. Twenty-two of the metastatic findings were in the brain, 16 were in the calvarium, and two were in the scalp. Conclusion. This study has demonstrated that addition of the brain to the limited whole body FDG-PET/CT scanning may provide important contributions to the patient’s clinical management especially in patients with lung cancer, bladder cancer, malignant melanoma, breast cancer, stomach cancer, and unknown primary tumor.

  10. High Dose MicroCT Does Not Contribute Toward Improved MicroPET/CT Image Quantitative Accuracy and Can Limit Longitudinal Scanning of Small Animals

    Directory of Open Access Journals (Sweden)

    Wendy A. McDougald

    2017-10-01

    Full Text Available Obtaining accurate quantitative measurements in preclinical Positron Emission Tomography/Computed Tomography (PET/CT imaging is of paramount importance in biomedical research and helps supporting efficient translation of preclinical results to the clinic. The purpose of this study was two-fold: (1 to investigate the effects of different CT acquisition protocols on PET/CT image quality and data quantification; and (2 to evaluate the absorbed dose associated with varying CT parameters.Methods: An air/water quality control CT phantom, tissue equivalent material phantom, an in-house 3D printed phantom and an image quality PET/CT phantom were imaged using a Mediso nanoPET/CT scanner. Collected data was analyzed using PMOD software, VivoQuant software and National Electric Manufactures Association (NEMA software implemented by Mediso. Measured Hounsfield Unit (HU in collected CT images were compared to the known HU values and image noise was quantified. PET recovery coefficients (RC, uniformity and quantitative bias were also measured.Results: Only less than 2 and 1% of CT acquisition protocols yielded water HU values < −80 and air HU values < −840, respectively. Four out of 11 CT protocols resulted in more than 100 mGy absorbed dose. Different CT protocols did not impact PET uniformity and RC, and resulted in <4% overall bias relative to expected radioactive concentration.Conclusion: Preclinical CT protocols with increased exposure times can result in high absorbed doses to the small animals. These should be avoided, as they do not contributed toward improved microPET/CT image quantitative accuracy and could limit longitudinal scanning of small animals.

  11. Day of Injury CT and Late MRI Findings: Cognitive Outcome in a Pediatric Sample with Complicated Mild Traumatic Brain Injury

    Science.gov (United States)

    Jantz, Paul B; Farrer, Thomas J.; Abildskov, Tracy J.; Dennis, Maureen; Gerhardt, Cynthia A.; Rubin, Kenneth H.; Stancin, Terry; Taylor, H. Gerry; Vannatta, Kathryn; Yeates, Keith Owen

    2016-01-01

    Objectives Complicated mild traumatic brain injury (mTBI) or cmTBI is based on the presence of visibly identifiable brain pathology on the day-of-injury computed tomography (CT) scan. In a pediatric sample the relation of DOI CT to late MRI findings and neuropsychological outcome was examined. Methods MRI (> 12 months) was obtained in pediatric cmTBI patients and a sample of orthopedically injured (OI) children. Those children with positive imaging findings (MRI+) were quantitatively compared to those without (MRI-) or with the OI sample. Groups were also compared in neurocognitive outcome from WASI subtests and the WISC-IV Processing Speed Index (PSI), along with the Test of Everyday Attention for Children (TEA-Ch) and a parent-rated behavioral functioning measure (ABAS-II). Results Despite the MRI+ group having significantly more DOI CT findings than the MRI-group, no quantitative differences were found. WASI Vocabulary and Matrix Reasoning scores were significantly lower, but not PSI, TEA-Ch or ABAS-II scores. MRI+ and MRI-groups did not differ on these measures. Conclusions Heterogeneity in the occurrence of MRI-identified focal pathology was not associated with uniform changes in quantitative analyses of brain structure in cmTBI. Increased number of DOI CT abnormalities was associated with lowered neuropsychological performance. PMID:26186038

  12. Interpretation of CT-Scan Sinograms to Study the Dynamic Flow Properties of a Fluidized Bed

    Science.gov (United States)

    Bennett, M. A.; Kryuchkov, S.; Kantzas, A.

    2007-06-01

    Fast moving objects typically produce poor quality images and motion-artifacts in Computed Tomography (CT) scans. The imaging of bubbling gas-solid fluidized beds, where many bubbles may pass through the sensing cross-section in a tomographic measurement, gives such a problem. Previously, one method of dealing with this problem was to remove artifacts from the reconstructed image itself through low pass filtering. However, this method leads to lost information from the images. When the concentration of bubbles is low, and their shape is close to cylindrically symmetric, analysis of consecutive scans in the raw data sinogram can also provide valuable information about the frequency of bubbles passing, and about their individual size, shape and position. Then, utilizing the inverse Abel transform, this information can then also be used to contribute to time averaged properties of the bed's behaviour such as voidage distribution, bubble phase area fraction and spatial bubble number distribution.

  13. Adapted Treatment Guided by Interim PET-CT Scan in Advanced Hodgkin's Lymphoma.

    Science.gov (United States)

    Johnson, Peter; Federico, Massimo; Kirkwood, Amy; Fosså, Alexander; Berkahn, Leanne; Carella, Angelo; d'Amore, Francesco; Enblad, Gunilla; Franceschetto, Antonella; Fulham, Michael; Luminari, Stefano; O'Doherty, Michael; Patrick, Pip; Roberts, Thomas; Sidra, Gamal; Stevens, Lindsey; Smith, Paul; Trotman, Judith; Viney, Zaid; Radford, John; Barrington, Sally

    2016-06-23

    We tested interim positron-emission tomography-computed tomography (PET-CT) as a measure of early response to chemotherapy in order to guide treatment for patients with advanced Hodgkin's lymphoma. Patients with newly diagnosed advanced classic Hodgkin's lymphoma underwent a baseline PET-CT scan, received two cycles of ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) chemotherapy, and then underwent an interim PET-CT scan. Images were centrally reviewed with the use of a 5-point scale for PET findings. Patients with negative PET findings after two cycles were randomly assigned to continue ABVD (ABVD group) or omit bleomycin (AVD group) in cycles 3 through 6. Those with positive PET findings after two cycles received BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone). Radiotherapy was not recommended for patients with negative findings on interim scans. The primary outcome was the difference in the 3-year progression-free survival rate between randomized groups, a noninferiority comparison to exclude a difference of 5 or more percentage points. A total of 1214 patients were registered; 937 of the 1119 patients (83.7%) who underwent an interim PET-CT scan according to protocol had negative findings. With a median follow-up of 41 months, the 3-year progression-free survival rate and overall survival rate in the ABVD group were 85.7% (95% confidence interval [CI], 82.1 to 88.6) and 97.2% (95% CI, 95.1 to 98.4), respectively; the corresponding rates in the AVD group were 84.4% (95% CI, 80.7 to 87.5) and 97.6% (95% CI, 95.6 to 98.7). The absolute difference in the 3-year progression-free survival rate (ABVD minus AVD) was 1.6 percentage points (95% CI, -3.2 to 5.3). Respiratory adverse events were more severe in the ABVD group than in the AVD group. BEACOPP was given to the 172 patients with positive findings on the interim scan, and 74.4% had negative findings on a third PET-CT scan; the 3-year progression

  14. Adapted Treatment Guided by Interim PET-CT Scan in Advanced Hodgkin’s Lymphoma

    Science.gov (United States)

    Johnson, Peter; Federico, Massimo; Kirkwood, Amy; Fosså, Alexander; Berkahn, Leanne; Carella, Angelo; d’Amore, Francesco; Enblad, Gunilla; Franceschetto, Antonella; Fulham, Michael; Luminari, Stefano; O’Doherty, Michael; Patrick, Pip; Roberts, Thomas; Sidra, Gamal; Stevens, Lindsey; Smith, Paul; Trotman, Judith; Viney, Zaid; Radford, John; Barrington, Sally

    2016-01-01

    Background We tested interim positron-emission tomography–computed tomography (PET-CT) as a measure of early response to chemotherapy in order to guide treatment for patients with advanced Hodgkin’s lymphoma. Methods Patients with newly diagnosed advanced classic Hodgkin’s lymphoma underwent a baseline PET-CT scan, received two cycles of ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) chemotherapy, and then underwent an interim PET-CT scan. Images were centrally reviewed with the use of a 5-point scale for PET findings. Patients with negative PET findings after two cycles were randomly assigned to continue ABVD (ABVD group) or omit bleomycin (AVD group) in cycles 3 through 6. Those with positive PET findings after two cycles received BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone). Radiotherapy was not recommended for patients with negative findings on interim scans. The primary outcome was the difference in the 3-year progression-free survival rate between randomized groups, a noninferiority comparison to exclude a difference of 5 or more percentage points. Results A total of 1214 patients were registered; 937 of the 1119 patients (83.7%) who underwent an interim PET-CT scan according to protocol had negative findings. With a median follow-up of 41 months, the 3-year progression-free survival rate and overall survival rate in the ABVD group were 85.7% (95% confidence interval [CI], 82.1 to 88.6) and 97.2% (95% CI, 95.1 to 98.4), respectively; the corresponding rates in the AVD group were 84.4% (95% CI, 80.7 to 87.5) and 97.6% (95% CI, 95.6 to 98.7). The absolute difference in the 3-year progression-free survival rate (ABVD minus AVD) was 1.6 percentage points (95% CI, −3.2 to 5.3). Respiratory adverse events were more severe in the ABVD group than in the AVD group. BEACOPP was given to the 172 patients with positive findings on the interim scan, and 74.4% had negative findings on a third

  15. Brain perfusion CT for acute stroke using a 256-slice CT: improvement of diagnostic information by large volume coverage.

    Science.gov (United States)

    Dorn, F; Muenzel, D; Meier, R; Poppert, H; Rummeny, E J; Huber, A

    2011-09-01

    To compare a 256-slice CT with a simulated standard CT for brain CT perfusion (CTP). CTP was obtained in 51 patients using a 256-slice CT (128 detector rows, flying z-focus, 8-cm detector width, 80 kV, 120mAs, 20 measurements, 1 CT image/2.5 s). Signal-to-noise ratios (SNR) were compared in grey and white matter. Perfusion maps were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in hypoperfused areas and corresponding contralateral regions. Two reconstructed 10-mm slices for simulation of a standard CT (SDCT) were compared with the complete data sets (large-volume CT, LVCT). Adequate image quality was achieved in 50/51 cases. SNR were significantly different in grey and white matter. A perfusion deficit was present in 27 data sets. Differences between the hypoperfusions and the control regions were significant for MTT and CBF, but not for CBV. Three lesions were missed by SDCT but detected by LVCT; 24 lesions were covered incompletely by SDCT, and 6 by LVCT. 21 lesions were detected completely by LVCT, but none by SDCT. CTP imaging of the brain using an increased detector width can detect additional ischaemic lesions and cover most ischaemic lesions completely.

  16. Brain perfusion CT for acute stroke using a 256-slice CT: improvement of diagnostic information by large volume coverage

    Energy Technology Data Exchange (ETDEWEB)

    Dorn, F. [Technical University, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Institut fuer Radiologie, Klinikum rechts der Isar der Technischen Universitaet Muenchen, Muenchen (Germany); Muenzel, D.; Meier, R.; Rummeny, E.J.; Huber, A. [Technical University, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Poppert, H. [Technical University, Department of Neurology, Klinikum rechts der Isar, Munich (Germany)

    2011-09-15

    To compare a 256-slice CT with a simulated standard CT for brain CT perfusion (CTP). CTP was obtained in 51 patients using a 256-slice CT (128 detector rows, flying z-focus, 8-cm detector width, 80 kV, 120mAs, 20 measurements, 1 CT image/2.5 s). Signal-to-noise ratios (SNR) were compared in grey and white matter. Perfusion maps were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in hypoperfused areas and corresponding contralateral regions. Two reconstructed 10-mm slices for simulation of a standard CT (SDCT) were compared with the complete data sets (large-volume CT, LVCT). Adequate image quality was achieved in 50/51 cases. SNR were significantly different in grey and white matter. A perfusion deficit was present in 27 data sets. Differences between the hypoperfusions and the control regions were significant for MTT and CBF, but not for CBV. Three lesions were missed by SDCT but detected by LVCT; 24 lesions were covered incompletely by SDCT, and 6 by LVCT. 21 lesions were detected completely by LVCT, but none by SDCT. CTP imaging of the brain using an increased detector width can detect additional ischaemic lesions and cover most ischaemic lesions completely. (orig.)

  17. Image reconstruction and scan configurations enabled by optimization-based algorithms in multispectral CT

    Science.gov (United States)

    Chen, Buxin; Zhang, Zheng; Sidky, Emil Y.; Xia, Dan; Pan, Xiaochuan

    2017-11-01

    Optimization-based algorithms for image reconstruction in multispectral (or photon-counting) computed tomography (MCT) remains a topic of active research. The challenge of optimization-based image reconstruction in MCT stems from the inherently non-linear data model that can lead to a non-convex optimization program for which no mathematically exact solver seems to exist for achieving globally optimal solutions. In this work, based upon a non-linear data model, we design a non-convex optimization program, derive its first-order-optimality conditions, and propose an algorithm to solve the program for image reconstruction in MCT. In addition to consideration of image reconstruction for the standard scan configuration, the emphasis is on investigating the algorithm’s potential for enabling non-standard scan configurations with no or minimum hardware modification to existing CT systems, which has potential practical implications for lowered hardware cost, enhanced scanning flexibility, and reduced imaging dose/time in MCT. Numerical studies are carried out for verification of the algorithm and its implementation, and for a preliminary demonstration and characterization of the algorithm in reconstructing images and in enabling non-standard configurations with varying scanning angular range and/or x-ray illumination coverage in MCT.

  18. Extracting Information From Previous Full-Dose CT Scan for Knowledge-Based Bayesian Reconstruction of Current Low-Dose CT Images.

    Science.gov (United States)

    Zhang, Hao; Han, Hao; Liang, Zhengrong; Hu, Yifan; Liu, Yan; Moore, William; Ma, Jianhua; Lu, Hongbing

    2016-03-01

    Markov random field (MRF) model has been widely employed in edge-preserving regional noise smoothing penalty to reconstruct piece-wise smooth images in the presence of noise, such as in low-dose computed tomography (LdCT). While it preserves edge sharpness, its regional smoothing may sacrifice tissue image textures, which have been recognized as useful imaging biomarkers, and thus it may compromise clinical tasks such as differentiating malignant vs. benign lesions, e.g., lung nodules or colon polyps. This study aims to shift the edge-preserving regional noise smoothing paradigm to texture-preserving framework for LdCT image reconstruction while retaining the advantage of MRF's neighborhood system on edge preservation. Specifically, we adapted the MRF model to incorporate the image textures of muscle, fat, bone, lung, etc. from previous full-dose CT (FdCT) scan as a priori knowledge for texture-preserving Bayesian reconstruction of current LdCT images. To show the feasibility of the proposed reconstruction framework, experiments using clinical patient scans were conducted. The experimental outcomes showed a dramatic gain by the a priori knowledge for LdCT image reconstruction using the commonly-used Haralick texture measures. Thus, it is conjectured that the texture-preserving LdCT reconstruction has advantages over the edge-preserving regional smoothing paradigm for texture-specific clinical applications.

  19. Advanced Approach of Material Region Detections on Fibre-Reinforced Concrete CT-Scans

    Directory of Open Access Journals (Sweden)

    Marek Pecha

    2017-01-01

    Full Text Available Detections of material regions on CT-scans of solids are commonly treated manually by an expert. Although such manual detections have many advantages, some amount of human error is also incorporated. Moreover, expert opinions may vary significantly. We present an application of the k-means++ clustering as an alternative option to manual way of material area detections. k-means++ clustering is derived from k-means (the method of vector quantization, originally from signal processing, popular for cluster analysis in data mining and image processing communities. The algorithm s main advantages are its simple implementation and fast convergence to a local optimum of an objective function. We benchmark the suggested approach on transverse CT-scans of a fibre-reinforced concrete solid. Moreover, we introduce a technique for processing air distribution, such that the appropriate pixels detected as the pixels of air are converted into pixels representing concrete. The technique is based on the connected component algorithm. Benchmark and results of proposed method conclude the paper.

  20. Stature estimation from scapular measurements by CT scan evaluation in an Italian population.

    Science.gov (United States)

    Giurazza, Francesco; Del Vescovo, Riccardo; Schena, Emilano; Cazzato, Roberto Luigi; D'Agostino, Francesco; Grasso, Rosario Francesco; Silvestri, Sergio; Zobel, Bruno Beomonte

    2013-07-01

    This study evaluated the correlation between scapula size and stature and developed standard equations in order to estimate stature by CT scan evaluation. A total of 200 healthy Italian subjects (100 men and 100 women, mean age 64.2±12.8years) underwent thoracic CT scan evaluation during pulmonary screening in our department; we measured the stature of each patient with standard anthropometric instruments and then analyzed images to calculate the longitudinal scapular length (LSL) and the transverse scapular length (TSL). The correlation between stature and each parameter measured was analyzed by dividing the population into two groups, males and females, and was examined by simple regression analysis using Pearson's correlation coefficient (r). Each anthropometric variable showed a significant difference between males and females (p value stature and LSL. Our study demonstrates that scapulae can be used for stature estimation; in our sample LSL was found to have a better correlation with stature then TSL. hm=4.247*LSL+93.74 and hf=4.031*LSL+92.38 are the formulae that provide the most accurate stature assessment in males and females respectively. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  1. Sex estimation in a contemporary Turkish population based on CT scans of the calcaneus.

    Science.gov (United States)

    Ekizoglu, Oguzhan; Inci, Ercan; Palabiyik, Figen Bakirtas; Can, Ismail Ozgur; Er, Ali; Bozdag, Mustafa; Kacmaz, Ismail Eralp; Kranioti, Elena F

    2017-10-01

    Building a reliable biological profile from decomposed remains depends heavily on the accurate estimation of sex. A variety of methods based on every single skeletal element have been developed over the years for different populations employing both osteological and virtual methods. The latter seem to be a reasonable alternative in countries lacking osteological reference collections. The current study used 3D virtual models of calcanei from CT scans of living adults to develop a sex estimation method for contemporary Turkish. Four hundred and twenty eight calcanei CT scans were analysed. The sample was divided in two subsamples: an original (N=348) and a validation sample (N=80) with similar distribution of males and females. Nine classical measurements were taken using the 3D models of the calcanei and two different statistical methods (Discriminant function analysis and Binary logistic regression) were used. Classification accuracy ranged from 82% to 98% for the validation sample and it was consistently high using any of the two methods. Sex bias seems to be lower for most of the logistic regression equations compared to the discriminant functions. These results, however, need further testing to be verified. Based on the results of this study we recommend the use of both methods for sex estimation from the measurements of the calcaneus bone in a Turkish population. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Static Myocardial Perfusion Imaging using denoised dynamic Rb-82 PET/CT scans

    DEFF Research Database (Denmark)

    Petersen, Maiken N.M.; Hoff, Camilla; Harms, Hans

    . Administered 82Rb dose was 1110 MBq. Denoising using HYPR-LR or Hotelling 3D algorithms was performed as post-processing on the dynamic images series. Static series were created by summing frames from 2.5-5 min. The image data was analysed in QPET (Cedars-Sinai). Relative segmental perfusion (normalized......Introduction: Relative and absolute measures of myocardial perfusion are derived from a single 82Rb PET/CT scan. However, images are inherently noising due to the short half-life of 82Rb. We have previously shown that denoising techniques can be applied to dynamic 82Rb series with excellent...... quantitative accuracy. In this study, we examine static images created by summing late frames of denoised dynamic series. Method: 47 random clinical 82Rb stress and rest scans (27 male, age 68+/- 12 y., BMI 27.9 +/- 5.5 kg/m2) performed on a GE Discovery 690 PET/CT scanner were included in the study...

  3. [Biometric and biomechanic analysis of lumbar posterior facets based on a CT-scan database].

    Science.gov (United States)

    Bronsard, N; Serre, T; Staccini, P; Hovorka, I; Thollon, L; Padovani, B; de Peretti, F; Signoli, M; Tropiano, P

    2013-03-01

    Our knowledge on anatomy of lumbar spine is based on few cadaver's study with old and few subjects. CT-scan is very precise for lumbar facet's morphology. We have analysed 400 subjects. The aim of this study is to measure different distances, angles and circles to better understand the mechanical function of the lumbar facets. We have analysed 720 CT-scan. We had 217 men and 183 women with 59 years of mean age. We used native slices of 1.25 mm thick from L1 to S1. We created transversal plan and we put different mark point. We took their coordinates and we have calculated different distances, angles and mechanical circles. We have compared different axis of rotation of the facets. From L1 to S1, the facets goes near to the posterior wall and far from themselves. Moreover, the posterior angle between both facets increase down to the sacrum. The radius of the left side circle and the right one are very closed in 50% of the cases but the three radius are close only in 10% of cases. This study based on 400 subjects shows that there is not a unique axis of rotation for both lumbar posterior facets. We have had only 50% of symmetry between both sides whatever the level studied. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  4. Evaluating 3D registration of CT-scan images using crest lines

    Science.gov (United States)

    Ayache, Nicholas; Gueziec, Andre P.; Thirion, Jean-Philippe; Gourdon, A.; Knoplioch, Jerome

    1993-06-01

    We consider the issue of matching 3D objects extracted from medical images. We show that crest lines computed on the object surfaces correspond to meaningful anatomical features, and that they are stable with respect to rigid transformations. We present the current chain of algorithmic modules which automatically extract the major crest lines in 3D CT-Scan images, and then use differential invariants on these lines to register together the 3D images with a high precision. The extraction of the crest lines is done by computing up to third order derivatives of the image intensity function with appropriate 3D filtering of the volumetric images, and by the 'marching lines' algorithm. The recovered lines are then approximated by splines curves, to compute at each point a number of differential invariants. Matching is finally performed by a new geometric hashing method. The whole chain is now completely automatic, and provides extremely robust and accurate results, even in the presence of severe occlusions. In this paper, we briefly describe the whole chain of processes, already presented to evaluate the accuracy of the approach on a couple of CT-scan images of a skull containing external markers.

  5. Contrast CT-scan for preoperative planning of VSLN (vascularized submental lymph-node) transfer.

    Science.gov (United States)

    Mullan, Damian; Kosutic, Damir

    2017-01-01

    Vascularized submental lymph-node (VSLN) transfer is gaining popularity as a reliable donor-site in microsurgical treatment of lymphedema. However, variations in number, location, and blood supply to submental lymph-nodes as well as associate skin-paddle make a predictable flap harvest a challenging task. We analyzed this region on preoperative imaging, to improve accuracy of VSLN transfers. Contrast CT-scan analysis of VSLN-flap areas was performed in 58 patients. Number and location of visibly vascularized lymph nodes as well as submental artery perforators were identified, documented, and compared. About 409 lymph-nodes were found in 50 patients. No significant difference was found in the number of nodes between the right and left side. Significantly more lymph-nodes were found in zones 1B than zones 1A. In eight patients nodes were not identified. In the remaining 50 patients position of the visibly vascularized submental lymph-node was predictable. Significantly less lymph-nodes can be found in zone 1a then zone 1b. Location of visibly vascularized lymph nodes can be identified predictably in relation to bony landmarks. Blood supply to 1a nodes and particularly location of dominant skin perforator is unpredictable due to potential crossover. Contrast CT scan can help identify location and blood supply to submental lymph-nodes in most patients. J. Surg. Oncol. 2017;115:23-26. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  6. Computer-aided detection and quantification of cavitary tuberculosis from CT scans.

    Science.gov (United States)

    Xu, Ziyue; Bagci, Ulas; Kubler, Andre; Luna, Brian; Jain, Sanjay; Bishai, William R; Mollura, Daniel J

    2013-11-01

    To present a computer-aided detection tool for identifying, quantifying, and evaluating tuberculosis (TB) cavities in the infected lungs from computed tomography (CT) scans. The authors' proposed method is based on a novel shape-based automated detection algorithm on CT scans followed by a fuzzy connectedness (FC) delineation procedure. In order to assess interaction between cavities and airways, the authors first roughly identified air-filled structures (airway, cavities, esophagus, etc.) by thresholding over Hounsfield unit of CT image. Then, airway and cavity structure detection was conducted within the support vector machine classification algorithm. Once airway and cavities were detected automatically, the authors extracted airway tree using a hybrid multiscale approach based on novel affinity relations within the FC framework and segmented cavities using intensity-based FC algorithm. At final step, the authors refined airway structures within the local regions of FC with finer control. Cavity segmentation results were compared to the reference truths provided by expert radiologists and cavity formation was tracked longitudinally from serial CT scans through shape and volume information automatically determined through the authors' proposed system. Morphological evolution of the cavitary TB were analyzed accordingly with this process. Finally, the authors computed the minimum distance between cavity surface and nearby airway structures by using the linear time distance transform algorithm to explore potential role of airways in cavity formation and morphological evolution. The proposed methodology was qualitatively and quantitatively evaluated on pulmonary CT images of rabbits experimentally infected with TB, and multiple markers such as cavity volume, cavity surface area, minimum distance from cavity surface to the nearest bronchial-tree, and longitudinal change of these markers (namely, morphological evolution of cavities) were determined precisely. While

  7. Deriving tissue density and elastic modulus from microCT bone scans.

    Science.gov (United States)

    Wagner, David W; Lindsey, Derek P; Beaupre, Gary S

    2011-11-01

    Tissue level density and elastic modulus are intrinsic properties that can be used to quantify bone material and analyses incorporating those quantities have been used to evaluate bone on a macroscopic scale. Micro-computed tomography (microCT) technology has been used to construct tissue level finite element models to simulate macroscopic fracture strength, however, a single method for assigning voxel-specific tissue density and elastic modulus based on those data has not been universally accepted. One method prevalent in the literature utilizes an empirical relationship that derives tissue stiffness as a function of bone calcium content weight fraction. To derive calcium content weight fraction from microCT scans, a measure of tissue density is required and a constant value is traditionally used. However, experimental data suggest a non-trivial amount of tissue heterogeneity suggesting a constant tissue density may not be appropriate. A theoretical derivation for determining the relationship between voxel-specific tissue density and microCT scan data (i.e., microCT derived tissue mineral density (TMD), mgHA/cm(3)) and bone constituent properties is proposed. Constant model parameters used in the derivation include the density of water, ash, and organics (i.e., bone constituents) and the volume fraction of the organics constituent. The effect of incorporating the theoretically derived tissue density (instead of a constant value) in determining voxel-specific elastic modulus resulted in a maximum observed increase of 12GPa (5.9GPa versus 17.9GPa, for the constant value and derived tissue density formulations, respectively) for a measured TMD of 1.02gHA/cm(3). Average and bounding quantities for the four constant model parameters were defined from the literature and the influence of those values on the derived tissue density and elastic modulus relationships were also evaluated. The theoretical relationships of tissue density and elastic modulus, with the average

  8. Chest CT scan screening for lung cancer in asbestos occupational exposure: a systematic review and meta-analysis.

    Science.gov (United States)

    Ollier, Marie; Chamoux, Alain; Naughton, Geraldine; Pereira, Bruno; Dutheil, Frédéric

    2014-06-01

    Lung cancer is the most frequent malignant asbestos-related pathology and remains the most fatal cancer of industrialized countries. In heavy smokers, early detection of lung cancer with chest CT scan leads to a 20% mortality reduction. However, the use of CT scan screening for early detection of lung cancer in asbestos-exposed workers requires further investigation. This study aimed to determine whether CT scan screening in asbestos-exposed workers is effective in detecting asymptomatic lung cancer using a systematic review and meta-analysis. We reviewed all cohort studies involving chest CT scan screening in former asbestos-exposed workers. The search strategy used the following keywords: "asbestos," "lung cancer," "screening," and "occupation*" or "work." Databases were PubMed, Cochrane Library, Science Direct, and Embase. Seven studies matched our inclusion criteria. Baseline screening detected 49 asymptomatic lung cancers among 5,074 asbestos-exposed workers. Of the 49 reported lung cancers, at least 18 were in the earliest stage (stage I), accessible to complete removal surgery. The prevalence of all lung cancers detected by CT scan screening in asbestos-exposed workers was 1.1% (95% CI, 0.6%-1.8%). CT scan screening in asbestos-exposed workers is effective in detecting asymptomatic lung cancer. Detection of lung cancer in asbestos-exposed workers using CT scanning is at least equal to the prevalence in heavy smokers (1%; 95% CI, 0.09%-1.1%) and also shared a similar proportion of stage I diagnoses. Screening asbestos-exposed workers could reduce mortality in proportions previously observed among heavy smokers and, thus, should not be neglected, particularly for individuals combining both exposures.

  9. Determination of entry site for acute type A aortic dissection by initial enhanced CT-scan

    Energy Technology Data Exchange (ETDEWEB)

    Mase, Takenori; Narumiya, Chihiro; Aoyama, Takahiko; Nagata, Yoshihisa [Aichi Medical Univ., Nagakute (Japan). School of Medicine

    2002-01-01

    Acute type A aortic dissection presents a surgical emergency because conservative therapy is not effective in the majority of instances. Enhanced CT-scan of the chest is commonly available and is considered to be an optimal diagnostic method for this disease. The operative strategy is to resect the primary tear to close the entry site of the aortic dissection and replace it with a tubular Dacron graft. Therefore, the existence of the entry site is important in determining the operative procedure. Based on the numerical value of the enhanced CT-scan inspection, the present study seeks to preoperatively identify the location of the presumed entry site in aortic dissection. From May 1996 to June 1999, 21 consecutive patients (Marfan's syndrome excluded) with acute type A aortic dissection underwent surgical treatment. Nineteen patients were preoperatively examined by enhanced CT-scan: 11 men and 8 women, with a mean age of 61 years. CT-scan slices used for early diagnosis were of the ascending aorta, aortic arch, descending aorta, and thoracoabdominal aorta. The largest diameters of the whole and true lumen were measured from cross-sectional aortic images with a personal computer, and the areas of the whole and true lumen were obtained by the manual tracing method. The true ratio was calculated for the largest diameter and area of the whole lumen. The nineteen patients were divided into two groups according to the location of the entry site based on the operating views. Seven patients with the entry site in the ascending aorta were classified as group A, and twelve patients with the entry site further in the aortic arch and descending aorta were classified as group B. Comparisons were performed by non-parametric analysis. Moreover, a discriminant analysis was applied to evaluate the classification between the two groups. The ratio of the largest diameter of the true lumen in group A at the level of the ascending and descending aorta was significantly greater than

  10. Automated segmentation and tracking of coronary arteries in ECG-gated cardiac CT scans

    Science.gov (United States)

    Zhou, Chuan; Chan, Heang-Ping; Chughtai, Aamer; Patel, Smita; Agarwal, Prachi; Hadjiiski, Lubomir M.; Sahiner, Berkman; Wei, Jun; Ge, Jun; Kazerooni, Ella A.

    2008-03-01

    Cardiac CT has been reported to be an effective means for clinical diagnosis of coronary artery plaque disease. We are investigating the feasibility of developing a computer-assisted image analysis (CAA) system to assist radiologist in detection of coronary artery plaque disease in ECG-gated cardiac CT scans. The heart region was first extracted using morphological operations and an adaptive EM thresholding method. Vascular structures in the heart volume were enhanced by 3D multi-scale filtering and analysis of the eigenvalues of Hessian matrices using a vessel enhancement response function specially designed for coronary arteries. The enhanced vascular structures were then segmented by an EM estimation method. Finally, our newly developed 3D rolling balloon vessel tracking method (RBVT) was used to track the segmented coronary arteries. Starting at two manually identified points located at the origins of left and right coronary artery (LCA and RCA), the RBVT method moved a sphere of adaptive diameter along the vessels, tracking the vessels and identifying its branches automatically to generate the left and right coronary arterial trees. Ten cardiac CT scans that contained various degrees of coronary artery diseases were used as test data set for our vessel segmentation and tracking method. Two experienced thoracic radiologists visually examined the computer tracked coronary arteries on a graphical interface to count untracked false-negative (FN) branches (segments). A total of 27 artery segments were identified to be FNs in the 10 cases, ranging from 0 to 6 FN segments in each case. No FN artery segment was found in 2 cases.

  11. Longitudinal dose distribution and energy absorption in PMMA and water cylinders undergoing CT scans.

    Science.gov (United States)

    Li, Xinhua; Zhang, Da; Liu, Bob

    2014-10-01

    The knowledge of longitudinal dose distribution provides the most direct view of the accumulated dose in computed tomography (CT) scanning. The purpose of this work was to perform a comprehensive study of dose distribution width and energy absorption with a wide range of subject sizes and beam irradiated lengths. Cumulative dose distribution along the z-axis was calculated based on the previously published CT dose equilibration data by Li, Zhang, and Liu [Med. Phys. 40, 031903 (10pp.) (2013)] and a mechanism for computing dose on axial lines by Li, Zhang, and Liu [Med. Phys. 39, 5347-5352 (2012)]. Full width at half maximum (FWHM), full width at tenth maximum (FWTM), the total energy (E) absorbed in a small cylinder of unit mass per centimeter square about the central or peripheral axis, and the energy (Ein) absorbed inside irradiated length (L) were subsequently extracted from the dose distribution. Extensive results of FWHM, FWTM, and Ein/E were presented on the central and peripheral axes of infinitely long PMMA (diameters 6-50 cm) and water (diameters 6-55 cm) cylinders with L explanation of dose distribution width results was presented. This study enables the reader to gain a comprehensive view of dose distribution width and energy absorption and provides useful data for estimating doses to organs inside or beyond the irradiated region. The dose length product (DLP) presented by CT scanners is equal to neither E nor Ein. Both E and Ein can be evaluated using the equations and results presented in this paper and are robust with both constant and variable tube current scanning techniques.

  12. Cross-Disciplinary Analysis of Lymph Node Classification in Lung Cancer on CT Scanning.

    Science.gov (United States)

    El-Sherief, Ahmed H; Lau, Charles T; Obuchowski, Nancy A; Mehta, Atul C; Rice, Thomas W; Blackstone, Eugene H

    2017-04-01

    Accurate and consistent regional lymph node classification is an important element in the staging and multidisciplinary management of lung cancer. Regional lymph node definition sets-lymph node maps-have been created to standardize regional lymph node classification. In 2009, the International Association for the Study of Lung Cancer (IASLC) introduced a lymph node map to supersede all preexisting lymph node maps. Our aim was to study if and how lung cancer specialists apply the IASLC lymph node map when classifying thoracic lymph nodes encountered on CT scans during lung cancer staging. From April 2013 through July 2013, invitations were distributed to all members of the Fleischner Society, Society of Thoracic Radiology, General Thoracic Surgical Club, and the American Association of Bronchology and Interventional Pulmonology to participate in an anonymous online image-based and text-based 20-question survey regarding lymph node classification for lung cancer staging on CT imaging. Three hundred thirty-seven people responded (approximately 25% participation). Respondents consisted of self-reported thoracic radiologists (n = 158), thoracic surgeons (n = 102), and pulmonologists who perform endobronchial ultrasonography (n = 77). Half of the respondents (50%; 95% CI, 44%-55%) reported using the IASLC lymph node map in daily practice, with no significant differences between subspecialties. A disparity was observed between the IASLC definition sets and their interpretation and application on CT scans, in particular for lymph nodes near the thoracic inlet, anterior to the trachea, anterior to the tracheal bifurcation, near the ligamentum arteriosum, between the bronchus intermedius and esophagus, in the internal mammary space, and adjacent to the heart. Use of older lymph node maps and inconsistencies in interpretation and application of definitions in the IASLC lymph node map may potentially lead to misclassification of stage and suboptimal management of lung

  13. Machine learning algorithm for automatic detection of CT-identifiable hyperdense lesions associated with traumatic brain injury

    Science.gov (United States)

    Keshavamurthy, Krishna N.; Leary, Owen P.; Merck, Lisa H.; Kimia, Benjamin; Collins, Scott; Wright, David W.; Allen, Jason W.; Brock, Jeffrey F.; Merck, Derek

    2017-03-01

    Traumatic brain injury (TBI) is a major cause of death and disability in the United States. Time to treatment is often related to patient outcome. Access to cerebral imaging data in a timely manner is a vital component of patient care. Current methods of detecting and quantifying intracranial pathology can be time-consuming and require careful review of 2D/3D patient images by a radiologist. Additional time is needed for image protocoling, acquisition, and processing. These steps often occur in series, adding more time to the process and potentially delaying time-dependent management decisions for patients with traumatic brain injury. Our team adapted machine learning and computer vision methods to develop a technique that rapidly and automatically detects CT-identifiable lesions. Specifically, we use scale invariant feature transform (SIFT)1 and deep convolutional neural networks (CNN)2 to identify important image features that can distinguish TBI lesions from background data. Our learning algorithm is a linear support vector machine (SVM)3. Further, we also employ tools from topological data analysis (TDA) for gleaning insights into the correlation patterns between healthy and pathological data. The technique was validated using 409 CT scans of the brain, acquired via the Progesterone for the Treatment of Traumatic Brain Injury phase III clinical trial (ProTECT_III) which studied patients with moderate to severe TBI4. CT data were annotated by a central radiologist and included patients with positive and negative scans. Additionally, the largest lesion on each positive scan was manually segmented. We reserved 80% of the data for training the SVM and used the remaining 20% for testing. Preliminary results are promising with 92.55% prediction accuracy (sensitivity = 91.15%, specificity = 93.45%), indicating the potential usefulness of this technique in clinical scenarios.

  14. Improving CT scan capabilities with a new trauma workflow concept: simulation of hospital logistics using different CT scanner scenarios

    NARCIS (Netherlands)

    Fung Kon Jin, P. H. P.; Dijkgraaf, M. G. W.; Alons, C. L.; van Kuijk, C.; Beenen, L. F. M.; Koole, G. M.; Goslings, J. C.

    2011-01-01

    The Amsterdam Trauma Workflow (ATW) concept includes a sliding gantry CT scanner serving two mirrored (trauma) rooms. In this study, several predefined scenarios with a varying number of CT scanners and CT locations are analyzed to identify the best performing patient flow management strategy from

  15. Survey regarding the clinical practice of cardiac CT in Germany. Indications, scanning technique and reporting

    Energy Technology Data Exchange (ETDEWEB)

    Maurer, Marc H.; Hamm, B.; Dewey, M. [Inst. fuer Radiologie, Charite - Universitaetsmedizin Berlin (Germany)

    2009-12-15

    Purpose: to obtain an overview of the current clinical practice of cardiac computed tomography (CT) in Germany. Materials and methods: a 30-item question-naire was mailed to 149 providers of cardiac CT in Germany. The items asked about indications, scanning technique and reporting, data storage, and cost of the examination. Results: overall 45 questionnaires could be analyzed (30%). The majority of centers (76%, 34 of 45 centers) used CT scanners of the latest generation (at least 64 rows). The most common appropriate indications were exclusion of coronary artery disease (91%, 41/45), coronary anomalies (80%, 36/45), and follow-up after coronary artery bypass grafting (53%, 24/45). Each center examined on average 243 {+-} 310 patients in 2007 and the number of centers performing cardiac CT increased significantly in 2007 (p = 0.035) compared with the preceding year. Most used sublingual nitroglycerin (84%, 38/45; median of 2 sprays = 0.8 mg) and/or a beta blocker (86%, 39/44; median of 5 mg IV, median heart rate threshold: 70 beats/min). Many providers used ECG-triggered tube current modulation (65%, 29/44) and/or adjusted the tube current to the body mass index or body weight (63%, 28/44). A median slice thickness of 0.75 mm with a 0.5 mm increment and a 20 cm field-of-view was most commonly used. Source images in orthogonal planes (96%, 43/45), curved MPRs (93%, 42/45), and thin-slice MIPs (69%, 31/45) were used most frequently for interpretation. Extracardiac structures were also evaluated by 84% of the centers (38/45). The mean examination time was 16.2 min and reporting took an average of 28.8 min. (orig.)

  16. Impact of Renal Failure on F18-FDG PET/CT Scans.

    Science.gov (United States)

    Kode, Vishwajit; Karsch, Holly; Osman, Medhat M; Muzaffar, Razi

    2017-01-01

    The current guidelines for 2-deoxy-2-[18F]fluoro-d-glucose PET/CT scanning do not address potential inaccuracies that may arise due to patients with renal failure. We report a retrospective analysis of standard uptake values (SUVs) in patients with and without renal failure in order to warrant a protocol adjustment. Patients were matched based on age, gender, and BMI all of which are potential effectors on observed SUV. Thirty patients were selected with clinically diagnosed renal failure, of which 12 were on dialysis. All 30 patients had age, gender, and BMI control matches. Blood urea nitrogen and creatinine levels were measured within 1 month of the scan to assess renal failure. PET/CT scans for both the renal failure patients and controls were performed 60 min after FDG injection. SUVs were measured by placing circular regions of interest in the right hepatic lobe (LSUV) and left psoas muscle (PSUV). For the 30 renal failure patients, the mean LSUV was 2.77 (SD = 0.57) and PSUV was 1.43 (SD = 0.30) while the controls had mean LSUV 2.74 (SD = 0.50) and PSUV 1.42 (SD = 0.37). The SUVs from both the liver and psoas muscle were not significantly different between the renal failure patients and the normal controls with p values >0.05. In addition, dialysis and gender also had no effect on SUVs. Our data suggest that renal failure patients do not require an adjustment in protocol and the standard protocol times should remain.

  17. Sigmoid sinus diverticulum and pulsatile tinnitus - Analysis of CT scans from 15 cases

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhaohui; Wang, Zhenchang; Xian, Junfang; Wang, Yongzhe; Liang, Xihong [Dept. of Radiology, Capital Medical Univ., Beijing Tongren Hospital, Beijing (China); Chen, Chengfang; Gong, Shusheng; Ma, Xiaobo; Li, Yi [Dept. of Otolaryngology Head and Neck Surgery, Capital Medical Univ., Beijing Tongren Hospital, Beijing (China)], e-mail: gongs@ccmu.edu.cn

    2013-09-15

    Background: Although the imaging features of sigmoid sinus diverticulum induced pulsatile tinnitus (PT) have been presented in some extent, detailed imaging findings still have not been systematically evaluated and precise diagnostic radiographic criteria has not been established. Purpose: To examine the computed tomography (CT) characteristics of sigmoid sinus diverticulum accompanied with PT. Material and Methods: Fifteen PT patients with sigmoid sinus diverticula proven by surgery were recruited after consenting. CT images of 15 patients were obtained and analyzed, including features of diverticula, brain venous systems, integrity of the sigmoid plate, and the degree of temporal bone pneumatization. Results: Sigmoid sinus diverticulum was located on the same side of PT in 15 patients. Diverticula originated at the superior curve of the sigmoid sinus in 11 patients and the descending segment of the sigmoid sinus in four patients. Sigmoid sinus diverticula focally eroded into the adjacent mastoid air cells in 12 patients and mastoid cortex in three patients. Among eight patients with unilateral dominant brain venous systems, the diverticula were seen on the dominant side in seven patients and non-dominant side in one patient. In contrast, the other seven patients showed co-dominant brain venous systems, with three presenting diverticula on the right side and four on the left. More notably, dehiscent sigmoid plate on the PT side was demonstrated in all patients. In addition, temporal bone hyper-pneumatization was found in nine patients, good and moderate pneumatization in three patients, respectively. Conclusion: Dehiscent sigmoid plate and extensive temporal bone pneumatization are two important imaging characteristics of the PT induced by sigmoid sinus diverticulum.

  18. Meningoencephalitis and new onset of seizures in an patient with normal brain CT and multiple lesions on MRI

    Energy Technology Data Exchange (ETDEWEB)

    Vidal, Jose E.; Spichler, Anne; Oliveira, Augusto C.P. de; Lomar, Andre Villela [Instituto de Infectologia Emilio Ribas, Sao Paulo, SP (Brazil)

    2004-02-01

    Toxoplasmic encephalitis is the most common cerebral mass lesion in patients with AIDS. The definitive diagnosis requires direct demonstration of the tachyzoite form of Toxoplasma gondii in cerebral tissue. The presumptive diagnosis is based on serology, clinical and radiological features, and on response to anti-Toxoplasma therapy. Typically, patients have a subacute presentation of focal neurological signs, with multiple lesions in computed tomography (CT) or magnetic resonance imaging (MRI). However, the neurological and CT scan spectrum is broad. We report a case of toxoplasmic encephalitis in a heterosexual man without prior history of HIV infection. He was admitted with four days of headache, confusion, and new onset of seizures. His brain CT disclosed no alterations and MRI revealed multiple lesions. Empirical specific anti-Toxoplasma therapy was initiated and the patient experienced excellent clinical and radiological improvement. His HIV tests were positive and the CD{sub 4}{sup +} cell count was 74 cells/ml (8.5 %). On follow up, three months later, the general state of the patient was good, without neurological sequelae and with a normal MRI. We concluded that toxoplasmic encephalitis should be considered in the differential diagnosis of meningoencephalitis in sexually active individuals, including cases without prior history or suspicion of HIV infection, and no abnormalities on CT scan. (author)

  19. SU-F-I-46: Optimizing Dose Reduction in Adult Head CT Protocols While Maintaining Image Quality in Postmortem Head Scans

    Energy Technology Data Exchange (ETDEWEB)

    Lipnharski, I; Carranza, C; Quails, N; Correa, N; Rajderkar, D; Bennett, J; Rill, L; Arreola, M [University of Florida, Gainesville, FL (United States)

    2016-06-15

    Purpose: To optimize adult head CT protocol by reducing dose to an appropriate level while providing CT images of diagnostic quality. Methods: Five cadavers were scanned from the skull base to the vertex using a routine adult head CT protocol (120 kVp, 270 mA, 0.75 s rotation, 0.5 mm × 32 detectors, 70.8 mGy CTDIvol) followed by seven reduced-dose protocols with varying combinations of reduced tube current, reduced rotation time, and increased detectors with CTDIvol ranging from 38.2 to 65.6 mGy. Organ doses were directly measured with 21 OSL dosimeters placed on the surface and implanted in the head by a neurosurgeon. Two neuroradiologists assessed grey-white matter differentiation, fluid space, ventricular size, midline shift, brain mass, edema, ischemia, and skull fractures on a three point scale: (1) Unacceptable, (2) Borderline Acceptable, and (3) Acceptable. Results: For the standard scan, doses to the skin, lens of the eye, salivary glands, thyroid, and brain were 37.55 mGy, 49.65 mGy, 40.67 mGy, 4.63 mGy, and 27.33 mGy, respectively. Two cadavers had cerebral edema due to changing dynamics of postmortem effects, causing the grey-white matter differentiation to appear less distinct. Two cadavers with preserved grey-white matter received acceptable scores for all image quality features for the protocol with a CTDIvol of 57.3 mGy, allowing organ dose savings ranging from 34% to 45%. One cadaver allowed for greater dose reduction for the protocol with a CTDIvol of 42 mGy. Conclusion: Efforts to optimize scan protocol should consider both dose and clinical image quality. This is made possible with postmortem subjects, whose brains are similar to patients, allowing for an investigation of ideal scan parameters. Radiologists at our institution accepted scan protocols acquired with lower scan parameters, with CTDIvol values closer to the American College of Radiology’s (ACR) Achievable Dose level of 57 mGy.

  20. Extraction of Line Features from Multifidus Muscle of CT Scanned Images with Morphologic Filter Together with Wavelet Multi Resolution Analysis

    OpenAIRE

    Yoichiro Kitajima; Yuichiro Eguchi; Kohei Arai

    2011-01-01

    A method for line feature extraction from multifidus muscle of Computer Tomography (CT) scanned image with morphologic filter together with wavelet based Multi Resolution Analysis (MRA) is proposed. The contour of the multifidus muscle can be extracted from hip CT image. The area of multifidus muscle is then estimated and is used for an index of belly fat because there is a high correlation between belly fat and multifidus muscle. When the area of the multifidus muscle was calculated from the...

  1. Mid-ventilation CT scan construction from four-dimensional respiration-correlated CT scans for radiotherapy planning of lung cancer patients

    NARCIS (Netherlands)

    Wolthaus, Jochem W. H.; Schneider, Christoph; Sonke, Jan-Jakob; van Herk, Marcel; Belderbos, José S. A.; Rossi, Maddalena M. G.; Lebesque, Joos V.; Damen, Eugène M. F.

    2006-01-01

    PURPOSE: Four-dimensional (4D) respiration-correlated imaging techniques can be used to obtain (respiration) artifact-free computed tomography (CT) images of the thorax. Current radiotherapy planning systems, however, do not accommodate 4D-CT data. The purpose of this study was to develop a simple,

  2. Use of CT scanning for the study of posterior lumbar intervertebral articulations

    Energy Technology Data Exchange (ETDEWEB)

    Hermanus, N.; de Becker, D.; Baleriaux, D.; Hauzeur, J.P.

    1983-01-01

    CT scan is peculiarly effective in the study of architectural pathologies of the column; it appears that a number of etiological factors of low back pain are involved and they are often related. Indeed, dis herniation, for instance, is frequently associated with facetal asymmetry, the first signs of arthroses and ligamentous calcification after treatment. The three vertebral axes must be evaluated, one discal and two facetal, the slightest defect in one of which can affect the two others. Moreover, in view of the complexity of the innervation, the entire lumbar column from L1 to L5 S1 must be investigated: it is not uncommonly that low sciatica is caused by a more cranial lumbar pathology. This systematic study promotes better understanding of the etiology of low back pain and suggests a stet judicious therapeutic attitude.

  3. The first ant-termite syninclusion in amber with CT-scan analysis of taphonomy.

    Science.gov (United States)

    Coty, David; Aria, Cédric; Garrouste, Romain; Wils, Patricia; Legendre, Frédéric; Nel, André

    2014-01-01

    We describe here a co-occurrence (i.e. a syninclusion) of ants and termites in a piece of Mexican amber (Totolapa deposit, Chiapas), whose importance is two-fold. First, this finding suggests at least a middle Miocene antiquity for the modern, though poorly documented, relationship between Azteca ants and Nasutitermes termites. Second, the presence of a Neivamyrmex army ant documents an in situ raiding behaviour of the same age and within the same community, confirmed by the fact that the army ant is holding one of the termite worker between its mandibles and by the presence of a termite with bitten abdomen. In addition, we present how CT-scan imaging can be an efficient tool to describe the topology of resin flows within amber pieces, and to point out the different states of preservation of the embedded insects. This can help achieving a better understanding of taphonomical processes, and tests ethological and ecological hypotheses in such complex syninclusions.

  4. A TR-induced algorithm for hot spots elimination through CT-scan HIFU simulations

    Science.gov (United States)

    Leduc, Nicolas; Okita, Kohei; Sugiyama, Kazuyasu; Takagi, Shu; Matsumoto, Yoichiro

    2011-09-01

    Although nowadays widely spread for imaging and treatments uses, HIFU techniques are still limited by the distortion of the wavefront due to refraction and reflection on the inhomogeneous media inside the human body. CT-scan Time Reversal (TR) procedure has risen as a promising candidate for focus control. A finite difference time domain parallelized code is used to provide simulations of TR-enhanced propagation through elements of the human body and implement a simple algorithm to address the issue of grating lobes, i.e secondary peaks of pressure due to natural diffraction by phased arrays and enhanced by medium heterogeneity. Using an iterative, progressive process combining secondary sound sources and independent signal summation, the primary peak is strengthened while secondary peaks are increasingly obliterated. This method supports the feasibility of precise modification and enhancement of the pressure profile in the targeted area through Time Reversal based solutions.

  5. Age estimation by 3D CT-scans of the Borremose Woman, a Danish bog body

    DEFF Research Database (Denmark)

    Villa, Chiara; Møller Rasmussen, Maria; Lynnerup, Niels

    2011-01-01

    been visualized from CT-scans using the Mimics software from Materialise. Extensive manual editing was necessary, as is common with bog bodies, since the bones were severely degraded and the ordinary range of Hounsfield Units (HU), used for clinical work, is not suitable. Only the cranium, the left...... ribs and the right auricular surface were 3D visualized. Based on these visualizations, the age was estimated by applying macroscopic methods routinely used for skeletal remains: the cranial sutures closure (Meindl & Lovejoy 1985), the sternal rib end (Iscan & Loth 1986) and the auricular surface...... was 16 to 24 years. Many problems had to be addressed. First of all, the degradation of the skeletal tissue does not allow a complete visualization: the bones are demineralized because of the acidic bog environment. Another problem is the subjectivity that can arise during manual editing, especially...

  6. Quantifying emphysema extent from weakly labeled CT scans of the lungs using label proportions learning

    DEFF Research Database (Denmark)

    Ørting, Silas Nyboe; Petersen, Jens; Wille, Mathilde

    2016-01-01

    Quantification of emphysema extent is important in diagnosing and monitoring patients with chronic obstructive pulmonary disease (COPD). Several studies have shown that emphysema quantification by supervised texture classification is more robust and accurate than traditional densitometry. Current...... techniques require highly time consuming manual annotations of patches or use only weak labels indicating overall disease status (e.g, COPD or healthy). We show how visual scoring of regional emphysema extent can be exploited in a learning with label proportions (LLP) framework to both predict presence...... of emphysema in smaller patches and estimate regional extent. We evaluate performance on 195 visually scored CT scans and achieve an intraclass correlation of 0.72 (0.65–0.78) between predicted region extent and expert raters. To our knowledge this is the first time that LLP methods have been applied...

  7. Image processing based detection of lung cancer on CT scan images

    Science.gov (United States)

    Abdillah, Bariqi; Bustamam, Alhadi; Sarwinda, Devvi

    2017-10-01

    In this paper, we implement and analyze the image processing method for detection of lung cancer. Image processing techniques are widely used in several medical problems for picture enhancement in the detection phase to support the early medical treatment. In this research we proposed a detection method of lung cancer based on image segmentation. Image segmentation is one of intermediate level in image processing. Marker control watershed and region growing approach are used to segment of CT scan image. Detection phases are followed by image enhancement using Gabor filter, image segmentation, and features extraction. From the experimental results, we found the effectiveness of our approach. The results show that the best approach for main features detection is watershed with masking method which has high accuracy and robust.

  8. Clinicopathological evaluation of the cases with positive ependymal enhancement by CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Atsuhiro; Akagi, Katsuhito; Horibe, Kunio; Yamasaki, Mami; Kurata, Akihiko

    1988-06-01

    A clinicopathological analysis of ependymal enhancement on CT scans found in 5 patients with neoplasm (N), 3 with infection (I), 2 with cerebral hemorrhage (CH), and 2 with cerebral infarction (CI) yielded the following findings. Ependymal enhancement was diffusely or partially observed during the clinical course. In the N group, ependymal enhancement was associated with positive cerebrospinal fluid in cytology and therapeutic response in 4 patients. Characteristic ventricular opacification was observed in 3 patients. In the groups of N and I, mortality rate was high (87 %), probably showing ependymal enhancement to be a sign of unfavorable prognosis. The groups of CH and CI had ventricular or intracerebral hemorrhage with rupture in ventricles and massive infarction. In evauable 5 patients at autopsy, major histological changes surrounding the ventricular wall included gliosis in the ependymal and subependymal layers, ependymal infiltration of tumor cells, destruction of ependyma, and neovascularization. These findings suggest some disturbance in ependymal and periventricular circulation. (Namekawa, K.).

  9. Gastric Schwannoma Presenting as an Incidentaloma on CT-Scan and MRI.

    Science.gov (United States)

    Raber, Menno H; Ziedses des Plantes, Cathelijne M P; Vink, Robert; Klaase, Joost M

    2010-12-01

    A 67 year old female was referred because of an incidentaloma on CT-scan and MRI which showed a 5.0 cm large mass in the wall of the distal stomach. After an initial work-up which suggested a gastrointestinal stromal tumor (GIST), a partial gastrectomy with a Billroth II gastrojejunostomy was performed. The histological diagnosis was a schwannoma. Gastric schwannomas are rare tumors which comprise 0.2% of all gastric tumors and 4% of all benign gastric neoplasms with a peak of incidence in the 4th and 5th decade of life. Gastric schwannomas are usually asymptomatic, but can present with ulceration and/or gastrointestinal bleeding. Clinical, endoscopical, surgical, radiological and histological features of this case are described and the relevant literature is reviewed.

  10. Comparison of two different segmentation methods on planar lung perfusion scan with reference to quantitative value on SPECT/CT

    Energy Technology Data Exchange (ETDEWEB)

    Suh, Min Seok; Kang, Yeon Koo; Ha, Seung Gyun [Dept. of Nuclear Medicine, Seoul National University Hospital, Seoul (Korea, Republic of); and others

    2017-06-15

    Until now, there was no single standardized regional segmentation method of planar lung perfusion scan. We compared planar scan based two segmentation methods, which are frequently used in the Society of Nuclear Medicine, with reference to the lung perfusion single photon emission computed tomography (SPECT)/computed tomography (CT) derived values in lung cancer patients. Fifty-five lung cancer patients (male:female, 37:18; age, 67.8 ± 10.7 years) were evaluated. The patients underwent planar scan and SPECT/CT after injection of technetium-99 m macroaggregated albumin (Tc-99 m-MAA). The % uptake and predicted postoperative percentage forced expiratory volume in 1 s (ppoFEV1%) derived from both posterior oblique (PO) and anterior posterior (AP) methods were compared with SPECT/CT derived parameters. Concordance analysis, paired comparison, reproducibility analysis and spearman correlation analysis were conducted. The % uptake derived from PO method showed higher concordance with SPECT/CT derived % uptake in every lobe compared to AP method. Both methods showed significantly different lobar distribution of % uptake compared to SPECT/CT. For the target region, ppoFEV1% measured from PO method showed higher concordance with SPECT/CT, but lower reproducibility compared to AP method. Preliminary data revealed that every method significantly correlated with actual postoperative FEV1%, with SPECT/CT showing the best correlation. The PO method derived values showed better concordance with SPECT/CT compared to the AP method. Both PO and AP methods showed significantly different lobar distribution compared to SPECT/CT. In clinical practice such difference according to different methods and lobes should be considered for more accurate postoperative lung function prediction.

  11. Possibilities of CT Scanning as Analysis Method in Laser Additive Manufacturing

    Science.gov (United States)

    Karme, Aleksis; Kallonen, Aki; Matilainen, Ville-Pekka; Piili, Heidi; Salminen, Antti

    Laser additive manufacturing is an established and constantly developing technique. Structural assessment should be a key component to ensure directed evolution towards higher level of manufacturing. The macroscopic properties of metallic structures are determined by their internal microscopic features, which are difficult to assess using conventional surface measuring methodologies. X-ray microtomography (CT) is a promising technique for three-dimensional non-destructive probing of internal composition and build of various materials. Aim of this study is to define the possibilities of using CT scanning as quality control method in LAM fabricated parts. Since the parts fabricated with LAM are very often used in high quality and accuracy demanding applications in various industries such as medical and aerospace, it is important to be able to define the accuracy of the build parts. The tubular stainless steel test specimens were 3D modelled, manufactured with a modified research AM equipment and imaged after manufacturing with a high-power, high-resolution CT scanner. 3D properties, such as surface texture and the amount and distribution of internal pores, were also evaluated in this study. Surface roughness was higher on the interior wall of the tube, and deviation from the model was systematically directed towards the central axis. Pore distribution showed clear organization and divided into two populations; one following the polygon model seams along both rims, and the other being associated with the concentric and equidistant movement path of the laser. Assessment of samples can enhance the fabrication by guiding the improvement of both modelling and manufacturing process.

  12. Where do neurologists look when viewing brain CT images? An eye-tracking study involving stroke cases.

    Directory of Open Access Journals (Sweden)

    Hideyuki Matsumoto

    Full Text Available The aim of this study was to investigate where neurologists look when they view brain computed tomography (CT images and to evaluate how they deploy their visual attention by comparing their gaze distribution with saliency maps. Brain CT images showing cerebrovascular accidents were presented to 12 neurologists and 12 control subjects. The subjects' ocular fixation positions were recorded using an eye-tracking device (Eyelink 1000. Heat maps were created based on the eye-fixation patterns of each group and compared between the two groups. The heat maps revealed that the areas on which control subjects frequently fixated often coincided with areas identified as outstanding in saliency maps, while the areas on which neurologists frequently fixated often did not. Dwell time in regions of interest (ROI was likewise compared between the two groups, revealing that, although dwell time on large lesions was not different between the two groups, dwell time in clinically important areas with low salience was longer in neurologists than in controls. Therefore it appears that neurologists intentionally scan clinically important areas when reading brain CT images showing cerebrovascular accidents. Both neurologists and control subjects used the "bottom-up salience" form of visual attention, although the neurologists more effectively used the "top-down instruction" form.

  13. What is a reliable CT scan for diagnosing splenosis under emergency conditions?

    Science.gov (United States)

    Garaci, Francesco Giuseppe; Grande, Michele; Villa, Massimo; Mancino, Stefano; Konda, Daniel; Attinà, Grazia Maria; Galatà, Gabriele; Simonetti, Giovanni

    2009-01-01

    Splenosis is a condition in which splenic tissue is present in a non-anatomical position. Implants of splenic tissue can mimic neoplasms and only specific examinations can confirm the correct diagnosis. Here we report a case of a 23-year-old male patient with a history of surgical splenectomy during childhood after trauma. He was admitted to the emergency department with acute bowel obstruction. An abdominal-pelvic computed tomography (CT) scan revealed small bowel obstruction and the presence of two rounded, solid masses located in the rectal-vescical pouch. Quantitative analyses of the different density values in the arterial phase and early portal venous phase demonstrated that these lesions were highly vascularised (92 and 97 Hounsfield Units, respectively). The hypothesis of an ectopic splenic mass was made after evaluation of the CT images and clinical history. The acute bowel obstruction caused by adhesive intestinal syndrome was resolved by surgical adhesiolysis. The smallest mass adherent to the rectum was removed. Histopathologic examination confirmed the benign nature of the lesion, which consisted of splenic tissue. PMID:19653350

  14. Postoperative follow-up of juvenile nasopharyngeal angiofibromas: assessment by CT scan and MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Chagnaud, C.; Petit, P.; Bartoli, J.M.; Champsaur, P.; Gaubert, J.Y.; Moulin, G. [Department of Radiology, Groupe Hospitalier de la Timone, Centre Hospitalier et Universitaire de Marseille, F-13385 Marseille Cedex 5 (France); Dessi, P.; Zanaret, M.; Cannoni, M. [Department of Head and Neck Surgery, Groupe Hospitalier de la Timone, Centre Hospitalier et Universitaire de Marseille, F-13385 Marseille Cedex 5 (France)

    1998-06-02

    The purpose of this study was to assess the radiological findings after surgical removal of juvenile nasopharyngeal angiofibromas (JNA). The postoperative CT and MRI scans of ten patients were reviewed. The cured group included six patients. The non-controlled group included six patients with eight recurrences. Two patients belonged to both groups as they were also followed and cured after surgery for relapse. Four recurrences were asymptomatic and diagnosed by imaging. The imaging patterns were matched to the patients clinical status and endoscopic findings. In the cured group, non-enhanced residual soft tissue masses were seen in all cases. In the non-controlled group, recurrence was always demonstrated on early postoperative CT or MR as a dramatically enhanced mass. The recurrence was located in the lateral or superior aspect of the nasopharynx (n = 3), deep to the fossa of Rosenmuller (n = 4) or out of the nasopharynx (n = 1). In two cases a remaining enhanced mass disappeared spontaneously on iterated examinations. Because of numerous asymptomatic relapses, a radiological workup is recommended four months after surgery, even in patients with normal endoscopy, to rule out posterolateral or extranasopharyngeal recurrences. Spontaneous evolution of residual masses must be appreciated on iterated imaging examinations. (orig.) With 8 figs., 2 tabs., 16 refs.

  15. An automatic virtual patient reconstruction from CT-scans for hepatic surgical planning.

    Science.gov (United States)

    Soler, L; Delingette, H; Malandain, G; Ayache, N; Koehl, C; Clément, J M; Dourthe, O; Marescaux, J

    2000-01-01

    PROBLEM/BACKGROUND: In order to help hepatic surgical planning we perfected automatic 3D reconstruction of patients from conventional CT-scan, and interactive visualization and virtual resection tools. From a conventional abdominal CT-scan, we have developed several methods allowing the automatic 3D reconstruction of skin, bones, kidneys, lung, liver, hepatic lesions, and vessels. These methods are based on deformable modeling or thresholding algorithms followed by the application of mathematical morphological operators. From these anatomical and pathological models, we have developed a new framework for translating anatomical knowledge into geometrical and topological constraints. More precisely, our approach allows to automatically delineate the hepatic and portal veins but also to label the portal vein and finally to build an anatomical segmentation of the liver based on Couinaud definition which is currently used by surgeons all over the world. Finally, we have developed a user friendly interface for the 3D visualization of anatomical and pathological structures, the accurate evaluation of volumes and distances and for the virtual hepatic resection along a user-defined cutting plane. A validation study on a 30 patients database gives 2 mm of precision for liver delineation and less than 1 mm for all other anatomical and pathological structures delineation. An in vivo validation performed during surgery also showed that anatomical segmentation is more precise than the delineation performed by a surgeon based on external landmarks. This surgery planning system has been routinely used by our medical partner, and this has resulted in an improvement of the planning and performance of hepatic surgery procedures. We have developed new tools for hepatic surgical planning allowing a better surgery through an automatic delineation and visualization of anatomical and pathological structures. These tools represent a first step towards the development of an augmented

  16. A reappraisal of adult thoracic and abdominal surface anatomy via CT scan in Chinese population.

    Science.gov (United States)

    Shen, Xin-Hua; Su, Bai-Yan; Liu, Jing-Juan; Zhang, Gu-Muyang; Xue, Hua-Dan; Jin, Zheng-Yu; Mirjalili, S Ali; Ma, Chao

    2016-03-01

    Accurate surface anatomy is essential for safe clinical practice. There are numerous inconsistencies in clinically important surface markings among and within contemporary anatomical reference texts. The aim of this study was to investigate key thoracic and abdominal surface anatomy landmarks in living Chinese adults using computed tomography (CT). A total of 100 thoracic and 100 abdominal CT scans were examined. Our results indicated that the following key surface landmarks differed from current commonly-accepted descriptions: the positions of the tracheal bifurcation, azygos vein termination, and pulmonary trunk bifurcation (all below the plane of the sternal angle at vertebral level T5-T6 in most individuals); the superior vena cava formation and junction with the right atrium (most often behind the 1st and 4th intercostal spaces, respectively); and the level at which the inferior vena cava and esophagus traverse the diaphragm (T10 and T11, respectively). The renal arteries were most commonly at L1; the midpoint of the renal hila was most frequently at L2; the 11th rib was posterior to the left kidney in only 29% of scans; and the spleen was most frequently located between the 10th and 12th ribs. A number of significant sex- and age-related differences were noted. The Chinese population was also compared with western populations on the basis of published reports. Reappraisal of surface anatomy using modern imaging tools in vivo will provide both quantitative and qualitative evidence to facilitate the clinical application of these key surface landmarks. © 2015 Wiley Periodicals, Inc.

  17. Comparative analysis of the radiation shield effect in an abdominal CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seon-Chil; Kim, Young-Jae [Daegu Health College, Daegu (Korea, Republic of); Lee, Joon-Seok [Daegu Fatima Hospital, Daegu (Korea, Republic of); Dong, Kyung-Rae [Gwangju Health University, Gwangju (Korea, Republic of); Chosun University, Gwangju (Korea, Republic of); Chung, Woon-Kwan [Chosun University, Gwangju (Korea, Republic of); Lim, Chang-Seon [Konyang University, Daejeon (Korea, Republic of)

    2014-03-15

    This study measured and compared the dose on the eyeballs and the thyroid with and without the use of a shield by applying the abdominal examination protocol used in an actual examination to a 64-channel computed tomography (CT) scan. A dummy phantom manufactured from acryl was used to measure the dose to the eyeballs and the thyroid of a patient during a thoraco-abdominal CT scan. The dose was measured using three dosimeters (optically-stimulated luminescence dosimeter (OSLD), thermoluminescence dosimeter (TLD) and photoluminescence dosimeter (PLD)) attached to the surfaces of three parts (left and right eyeballs and thyroid) in a phantom with and without the use of a shield for the eyeballs and the thyroid. Two types of shields (1-mm barium shielding sheet and 1-mm tungsten shielding sheet) were used for the measurements. The goggles and the lead shield, which are normally used in clinical practice, were used to compare the shield ratios of the shields. According to the results of the measurements made by using the OSLD, the shield ratios of the barium and the tungsten sheets were in the range of 34 - 36%. The measurements made by using the TLD showed that the shield ratio of the barium sheet was 6.25% higher than that of the tungsten sheet. When the PLD was used for the measurement, the shield ratio of the barium sheet was 33.34%, which was equivalent to that of the tungsten sheet. These results confirmed that the cheap barium sheet had a better shielding effect than the expensive tungsten sheet.

  18. A reassessment of cervical surface anatomy via CT scan in an adult population.

    Science.gov (United States)

    Shen, Xin-Hua; Xue, Hua-Dan; Chen, Yu; Wang, Man; Mirjalili, S Ali; Zhang, Zhu-Hua; Ma, Chao

    2017-04-01

    Surface landmarks in the neck are important for orientations of cervical glands, arteries, veins, nerves, and vertebrae. Recent research suggests some orientations are not correct. What are the cervical landmark orientations in the Chinese population? In this study, two essential cervical anatomy planes, the thyroid cartilage and C7 planes, were assessed in living adult Chinese subjects using computed tomography (CT), and the hyoid, carotid bifurcation, cricoid cartilage, thyroid arteries, and vertebral artery were simultaneously positioned. After excluding patients with distorting pathology, a total of 108 cervical CT scans were examined. The thyroid cartilage plane commonly passed through the C5 (in males) or C4 (in females) vertebral level. The carotid artery bifurcated most commonly at C3 (left) or C4 (right), more than 10 mm above the thyroid cartilage plane bilaterally in most cases. Orientation of the carotid bifurcation according to the body or greater horn of the hyoid was more accurate. The superior thyroid artery was found a finger-breadth below the thyroid cartilage plane, and the inferior thyroid artery in the C7 plane. The inferior border of the cricoid cartilage was most often at C7 (in males) or C6 (in females). The vertebral artery entered the C6 transverse foramen in more than 80% of scans. This reassessment of cervical surface anatomy using modern imaging tools in vivo provides both qualitative and quantitative information for surgeons in clinical practice. Clin. Anat. 30:330-335, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  19. Association of initial CT findings with quality-of-life outcomes for traumatic brain injury in children

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, Jonathan O. [Seattle Children' s Hospital and University of Washington, Department of Radiology, Seattle, WA (United States); Vavilala, Monica S.; Wang, Jin; Rivara, Frederick P. [Harborview Medical Center, University of Washington, Department of Pediatrics, Seattle, WA (United States); Pruthi, Sumit [Monroe Carell Jr. Children' s Hospital at Vanderbilt University, Department of Radiology, Nashville, TN (United States); Fink, James [University of Washington, Department of Radiology, Seattle, WA (United States); Jaffe, Kenneth M. [University of Washington, Department of Rehabilitation Medicine, Seattle, WA (United States); Durbin, Dennis [University of Pennsylvania, Department of Pediatrics, Center for Injury Research and Prevention, The Children' s Hospital of Philadelphia, Philadelphia, PA (United States); Koepsell, Thomas [University of Washington, Department of Epidemiology, Seattle, WA (United States); Temkin, Nancy [University of Washington, Biostatistics, Seattle, WA (United States)

    2012-08-15

    Traumatic brain injury (TBI) is a leading cause of acquired disability in children and adolescents. To demonstrate the association between specific findings on initial noncontrast head CT and long-term outcomes in children who have suffered TBI. This was an IRB-approved prospective study of children ages 2-17 years treated in emergency departments for TBI and who underwent a head CT as part of the initial work-up (n = 347). The change in quality of life at 12 months after injury was measured by the PedsQL scale. Children with TBI who had intracranial injuries identified on the initial head CT had a significantly lower quality-of-life scores compared to children with TBI whose initial head CTs were normal. In multivariate analysis, children whose initial head CT scans demonstrated intraventricular hemorrhage, parenchymal injury, midline shift {>=}5 mm, hemorrhagic shear injury, abnormal cisterns or subdural hematomas {>=}3 mm had lower quality of life scores 1 year after injury than children whose initial CTs did not have these same injuries. Associations exist between findings from the initial noncontrast head CT and quality of life score 12 months after injury in children with TBI. (orig.)

  20. Offline RF thermal ablation planning using CT/MRI scan data

    Directory of Open Access Journals (Sweden)

    Md. Faruk Ali

    2015-03-01

    Full Text Available In this paper, steady state temperature variations in the human brain due to different electrical and physical changes have been studied considering different thermal ablation treatment requirements using RF probe. Initially, a subject specific voxel-based electrical model has been constructed from Digital Imaging and Communication in Medicine (DICOM formatted Computed Tomography (CT or Magnetic Resonance (MR based image stacks with different pixel characteristics using the Hounsfield unit extraction technique. This subject specific electrical model that consists of different dielectric constant and conductivity, considering different anatomical organs and tissues is simulated using commercially available finite integral technique (FIT based EM simulation software CST Microwave Studio®. This study clearly shows the possibility of subject specific precise offline microwave thermal ablation treatment planning.

  1. High-fidelity artifact correction for cone-beam CT imaging of the brain

    Science.gov (United States)

    Sisniega, A.; Zbijewski, W.; Xu, J.; Dang, H.; Stayman, J. W.; Yorkston, J.; Aygun, N.; Koliatsos, V.; Siewerdsen, J. H.

    2015-02-01

    CT is the frontline imaging modality for diagnosis of acute traumatic brain injury (TBI), involving the detection of fresh blood in the brain (contrast of 30-50 HU, detail size down to 1 mm) in a non-contrast-enhanced exam. A dedicated point-of-care imaging system based on cone-beam CT (CBCT) could benefit early detection of TBI and improve direction to appropriate therapy. However, flat-panel detector (FPD) CBCT is challenged by artifacts that degrade contrast resolution and limit application in soft-tissue imaging. We present and evaluate a fairly comprehensive framework for artifact correction to enable soft-tissue brain imaging with FPD CBCT. The framework includes a fast Monte Carlo (MC)-based scatter estimation method complemented by corrections for detector lag, veiling glare, and beam hardening. The fast MC scatter estimation combines GPU acceleration, variance reduction, and simulation with a low number of photon histories and reduced number of projection angles (sparse MC) augmented by kernel de-noising to yield a runtime of ~4 min per scan. Scatter correction is combined with two-pass beam hardening correction. Detector lag correction is based on temporal deconvolution of the measured lag response function. The effects of detector veiling glare are reduced by deconvolution of the glare response function representing the long range tails of the detector point-spread function. The performance of the correction framework is quantified in experiments using a realistic head phantom on a testbench for FPD CBCT. Uncorrected reconstructions were non-diagnostic for soft-tissue imaging tasks in the brain. After processing with the artifact correction framework, image uniformity was substantially improved, and artifacts were reduced to a level that enabled visualization of ~3 mm simulated bleeds throughout the brain. Non-uniformity (cupping) was reduced by a factor of 5, and contrast of simulated bleeds was improved from ~7 to 49.7 HU, in good agreement

  2. Clinical importance of re-interpretation of PET/CT scanning in patients referred to a tertiary care medical centre

    DEFF Research Database (Denmark)

    Löfgren, Johan; Loft, Annika; Barbosa de Lima, Vinicius Araújo

    2017-01-01

    PURPOSE: To evaluate, in a controlled prospective manner with double-blind read, whether there are differences in interpretations of PET/CT scans at our tertiary medical centre, Rigshospitalet, compared to the external hospitals. METHODS: Ninety consecutive patients referred to our department who...... had an external F-18-FDG PET/CT scan were included. Only information that had been available at the time of the initial reading at the external hospital was available at re-interpretation. Teams with one radiologist and one nuclear medicine physician working side by side performed the re...

  3. Computed tomographic brain scan findings in Q fever encephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Aranda, F.; Romero Acebal, M.; Maestre Moreno, J.; Pachon Diaz, J.; Lopez Cortes, L.; Navarro Rodriguez, A.

    1984-07-01

    Neurological involvement in Q Fever is unusual. We present a case of encephalitis due to Coxiella Burnetii with neuroradiologic findings on CT not described previously, consisting in areas of decreased absorption coefficient in the subcortical white matter of both hemispheres, predominantly in the right. Differential diagnosis must be established from viral encephalitis, of similar clinical presentation, which may show similar CT lesions to those in this case.

  4. Assessment of bone metastasis using nuclear medicine imaging in breast cancer: comparison between PET/CT and bone scan

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Dae Hyoun; Ahn, Byeong Cheol; Kang, Sung Min [Kyungpook National University Medical School, Daegu (Korea, Republic of)] (and others)

    2007-02-15

    Bone metastasis in breast cancer patients are usually assessed by conventional Tc-99m methylene diphosphonate whole-body bone scan, which has a high sensitivity but a poor specificity. However, positron emission tomography with {sup 18}F-2-deoxyglucose (FDG-PET) can offer superior spatial resolution and improved specificity. FDG-PET/CT can offer more information to assess bone metastasis than PET alone, by giving a anatomical information of non-enhanced CT image. We attempted to evaluate the usefulness of FDG-PET/CT for detecting bone metastasis in breast cancer and to compare FDG-PET/CT results with bone scan findings. The study group comprised 157 women patients (range: 28 {approx} 78 years old, mean {+-} SD = 49.5 {+-}8.5) with biopsy-proven breast cancer who underwent bone scan and FDG-PET/CT within 1 week interval. The final diagnosis of bone metastasis was established by histopathological findings, radiological correlation, or clinical follow-up. Bone scan was acquired over 4 hours after administration of 740 MBq Tc-99m MDP. Bone scan image was interpreted as normal, low, intermediate or high probability for osseous metastasis. FDG PET/CT was performed after 6 hours fasting. 370 MBq F-18 FDG was administered intravenously 1 hour before imaging. PET data was obtained by 3D mode and CT data, used as transmission correction database, was acquired during shallow respiration. PET images were evaluated by visual interpretation, and quantification of FDG accumulation in bone lesion was performed by maximal SUV(SUVmax) and relative SUV(SUVrel). Six patients (4.4%) showed metastatic bone lesions. Four (66.6%) of 6 patients with osseous metastasis was detected by bone scan and all 6 patients (100%) were detected by PET/CT. A total of 135 bone lesions found on either FDG-PET or bone scan were consist of 108 osseous metastatic lesion and 27 benign bone lesions. Osseous metastatic lesion had higher SUVmax and SUVrel compared to benign bone lesion (4.79 {+-} 3.32 vs 1

  5. Effect of CT scanning parameters on volumetric measurements of pulmonary nodules by 3D active contour segmentation: a phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Way, Ted W; Chan, H-P; Goodsitt, Mitchell M; Sahiner, Berkman; Hadjiiski, Lubomir M; Zhou Chuan; Chughtai, Aamer [Department of Radiology, University of Michigan, Ann Arbor, MI 48109 (United States)], E-mail: tway@umich.edu

    2008-03-07

    The purpose of this study is to investigate the effects of CT scanning and reconstruction parameters on automated segmentation and volumetric measurements of nodules in CT images. Phantom nodules of known sizes were used so that segmentation accuracy could be quantified in comparison to ground-truth volumes. Spherical nodules having 4.8, 9.5 and 16 mm diameters and 50 and 100 mg cc{sup -1} calcium contents were embedded in lung-tissue-simulating foam which was inserted in the thoracic cavity of a chest section phantom. CT scans of the phantom were acquired with a 16-slice scanner at various tube currents, pitches, fields-of-view and slice thicknesses. Scans were also taken using identical techniques either within the same day or five months apart for study of reproducibility. The phantom nodules were segmented with a three-dimensional active contour (3DAC) model that we previously developed for use on patient nodules. The percentage volume errors relative to the ground-truth volumes were estimated under the various imaging conditions. There was no statistically significant difference in volume error for repeated CT scans or scans taken with techniques where only pitch, field of view, or tube current (mA) were changed. However, the slice thickness significantly (p < 0.05) affected the volume error. Therefore, to evaluate nodule growth, consistent imaging conditions and high resolution should be used for acquisition of the serial CT scans, especially for smaller nodules. Understanding the effects of scanning and reconstruction parameters on volume measurements by 3DAC allows better interpretation of data and assessment of growth. Tracking nodule growth with computerized segmentation methods would reduce inter- and intraobserver variabilities.

  6. Effect of CT scanning parameters on volumetric measurements of pulmonary nodules by 3D active contour segmentation: a phantom study

    Science.gov (United States)

    Way, Ted W.; Chan, Heang-Ping; Goodsitt, Mitchell M.; Sahiner, Berkman; Hadjiiski, Lubomir M.; Zhou, Chuan; Chughtai, Aamer

    2008-03-01

    The purpose of this study is to investigate the effects of CT scanning and reconstruction parameters on automated segmentation and volumetric measurements of nodules in CT images. Phantom nodules of known sizes were used so that segmentation accuracy could be quantified in comparison to ground-truth volumes. Spherical nodules having 4.8, 9.5 and 16 mm diameters and 50 and 100 mg cc-1 calcium contents were embedded in lung-tissue-simulating foam which was inserted in the thoracic cavity of a chest section phantom. CT scans of the phantom were acquired with a 16-slice scanner at various tube currents, pitches, fields-of-view and slice thicknesses. Scans were also taken using identical techniques either within the same day or five months apart for study of reproducibility. The phantom nodules were segmented with a three-dimensional active contour (3DAC) model that we previously developed for use on patient nodules. The percentage volume errors relative to the ground-truth volumes were estimated under the various imaging conditions. There was no statistically significant difference in volume error for repeated CT scans or scans taken with techniques where only pitch, field of view, or tube current (mA) were changed. However, the slice thickness significantly (p < 0.05) affected the volume error. Therefore, to evaluate nodule growth, consistent imaging conditions and high resolution should be used for acquisition of the serial CT scans, especially for smaller nodules. Understanding the effects of scanning and reconstruction parameters on volume measurements by 3DAC allows better interpretation of data and assessment of growth. Tracking nodule growth with computerized segmentation methods would reduce inter- and intraobserver variabilities.

  7. Accurate CT-MR image registration for deep brain stimulation: a multi-observer evaluation study

    Science.gov (United States)

    Rühaak, Jan; Derksen, Alexander; Heldmann, Stefan; Hallmann, Marc; Meine, Hans

    2015-03-01

    Since the first clinical interventions in the late 1980s, Deep Brain Stimulation (DBS) of the subthalamic nucleus has evolved into a very effective treatment option for patients with severe Parkinson's disease. DBS entails the implantation of an electrode that performs high frequency stimulations to a target area deep inside the brain. A very accurate placement of the electrode is a prerequisite for positive therapy outcome. The assessment of the intervention result is of central importance in DBS treatment and involves the registration of pre- and postinterventional scans. In this paper, we present an image processing pipeline for highly accurate registration of postoperative CT to preoperative MR. Our method consists of two steps: a fully automatic pre-alignment using a detection of the skull tip in the CT based on fuzzy connectedness, and an intensity-based rigid registration. The registration uses the Normalized Gradient Fields distance measure in a multilevel Gauss-Newton optimization framework and focuses on a region around the subthalamic nucleus in the MR. The accuracy of our method was extensively evaluated on 20 DBS datasets from clinical routine and compared with manual expert registrations. For each dataset, three independent registrations were available, thus allowing to relate algorithmic with expert performance. Our method achieved an average registration error of 0.95mm in the target region around the subthalamic nucleus as compared to an inter-observer variability of 1.12 mm. Together with the short registration time of about five seconds on average, our method forms a very attractive package that can be considered ready for clinical use.

  8. Low-dose dynamic myocardial perfusion CT image reconstruction using pre-contrast normal-dose CT scan induced structure tensor total variation regularization

    Science.gov (United States)

    Gong, Changfei; Han, Ce; Gan, Guanghui; Deng, Zhenxiang; Zhou, Yongqiang; Yi, Jinling; Zheng, Xiaomin; Xie, Congying; Jin, Xiance

    2017-04-01

    Dynamic myocardial perfusion CT (DMP-CT) imaging provides quantitative functional information for diagnosis and risk stratification of coronary artery disease by calculating myocardial perfusion hemodynamic parameter (MPHP) maps. However, the level of radiation delivered by dynamic sequential scan protocol can be potentially high. The purpose of this work is to develop a pre-contrast normal-dose scan induced structure tensor total variation regularization based on the penalized weighted least-squares (PWLS) criteria to improve the image quality of DMP-CT with a low-mAs CT acquisition. For simplicity, the present approach was termed as ‘PWLS-ndiSTV’. Specifically, the ndiSTV regularization takes into account the spatial-temporal structure information of DMP-CT data and further exploits the higher order derivatives of the objective images to enhance denoising performance. Subsequently, an effective optimization algorithm based on the split-Bregman approach was adopted to minimize the associative objective function. Evaluations with modified dynamic XCAT phantom and preclinical porcine datasets have demonstrated that the proposed PWLS-ndiSTV approach can achieve promising gains over other existing approaches in terms of noise-induced artifacts mitigation, edge details preservation, and accurate MPHP maps calculation.

  9. X-ray CT Scanning Reveals Long-Term Copper Pollution Effects on Functional Soil Structure

    DEFF Research Database (Denmark)

    Naveed, Muhammad; Møldrup, Per; Homstrup, Martin

    factors such as soil type, land use, and soil contamination. In this study, we quantified the soil structure using X-ray CT scanning and revealed the effect of a long history of Copper (Cu) pollution on it. A fallow field at Hygum Denmark provides this opportunity as it had a long history of Copper...... sulphate contamination in a gradient with Cu content varies from 21 mg kg-1 to 3837 mg kg-1. Total 20 intact soil columns (diameter of 10 cm and height of 8 cm) were sampled at five locations along the Cu-gradient from a depth of 5 to 15 cm below surface level. The soil columns were scanned at a voxel...... resolution of 0.21 mm x 0.21 mm x 0.21 mm. Images were analyzed using the Image-J software. Three-dimensional visualization of macropores showed that biopores (pores formed by organisms and plant roots) are present in abundance in this field at a Cu level of 21 mg kg-1 and decreased as the Cu content...

  10. What are the potential advantages and disadvantages of volumetric CT scanning?

    Science.gov (United States)

    Voros, Szilard

    2009-01-01

    After the introduction and dissemination of 64-slice multislice computed tomography systems, cardiovascular CT has arrived at a crossroad, and different philosophies lead down different paths of technologic development. Increased number of detector rows in the z-axis led to the introduction of dynamic, volumetric scanning of the heart and allows for whole-organ imaging. Dynamic, volumetric "whole-organ" scanning significantly reduces image acquisition time; "single-beat whole-heart imaging" results in improved image quality and reduced radiation exposure and reduced contrast dose. It eliminates helical and pitch artifacts and allows for simultaneous imaging of the base and apex of the heart. Beyond coronary arterial luminal imaging, such innovations open up the opportunity for myocardial perfusion and viability imaging and coronary arterial plaque imaging. Dual-source technology with 2 x-ray tubes placed at 90-degree angles provides heart rate-independent temporal resolution and has the potential for tissue characterization on the basis of different attenuation values at different energy levels. Refined detector technology allows for improved low-contrast resolution and may be beneficial for more detailed evaluation of coronary arterial plaque composition. The clinical benefit of each of these technologies will have to be evaluated in carefully designed clinical trials and in everyday clinical practice. Such combined experience will probably show the relative benefit of each of these philosophies in different patient populations and in different clinical scenarios.

  11. Volumetric gain of the human pancreas after left partial pancreatic resection: A CT-scan based retrospective study.

    Science.gov (United States)

    Phillip, Veit; Zahel, Tina; Danninger, Assiye; Erkan, Mert; Dobritz, Martin; Steiner, Jörg M; Kleeff, Jörg; Schmid, Roland M; Algül, Hana

    2015-01-01

    Regeneration of the pancreas has been well characterized in animal models. However, there are conflicting data on the regenerative capacity of the human pancreas. The aim of the present study was to assess the regenerative capacity of the human pancreas. In a retrospective study, data from patients undergoing left partial pancreatic resection at a single center were eligible for inclusion (n = 185). Volumetry was performed based on 5 mm CT-scans acquired through a 256-slice CT-scanner using a semi-automated software. Data from 24 patients (15 males/9 females) were included. Mean ± SD age was 68 ± 11 years (range, 40-85 years). Median time between surgery and the 1st postoperative CT was 9 days (range, 0-27 days; IQR, 7-13), 55 days (range, 21-141 days; IQR, 34-105) until the 2nd CT, and 191 days (range, 62-1902; IQR, 156-347) until the 3rd CT. The pancreatic volumes differed significantly between the first and the second postoperative CT scans (median volume 25.6 mL and 30.6 mL, respectively; p = 0.008) and had significantly increased further by the 3rd CT scan (median volume 37.9 mL; p = 0.001 for comparison with 1st CT scan and p = 0.003 for comparison with 2nd CT scan). The human pancreas shows a measurable and considerable potential of volumetric gain after partial resection. Multidetector-CT based semi-automated volume analysis is a feasible method for follow-up of the volume of the remaining pancreatic parenchyma after partial pancreatectomy. Effects on exocrine and endocrine pancreatic function have to be evaluated in a prospective manner. Copyright © 2015 IAP and EPC. Published by Elsevier B.V. All rights reserved.

  12. Are There Any Additional Benefits to Performing Positron Emission Tomography/Computed Tomography Scans and Brain Magnetic Resonance Imaging on Patients with Ground-Glass Nodules Prior to Surgery?

    Science.gov (United States)

    Song, Jae Uk; Song, Junwhi; Lee, Kyung Jong; Kim, Hojoong; Kwon, O Jung; Choi, Joon Young; Kim, Jhingook; Han, Joungho; Um, Sang Won

    2017-10-01

    A ground-glass nodule (GGN) represents early-stage lung adenocarcinoma. However, there is still no consensus for preoperative staging of GGNs. Therefore, we evaluated the need for the routine use of positron emission tomography/computed tomography (PET)/computed tomography (CT) scans and brain magnetic resonance imaging (MRI) during staging. A retrospective analysis was undertaken in 72 patients with 74 GGNs of less than 3 cm in diameter, which were confirmed via surgery as malignancy, at the Samsung Medical Center between May 2010 and December 2011. The median age of the patients was 59 years. The median GGN diameter was 18 mm. Pure and part-solid GGNs were identified in 35 (47.3%) and 39 (52.7%) cases, respectively. No mediastinal or distant metastasis was observed in these patients. In preoperative staging, all of the 74 GGNs were categorized as stage IA via chest CT scans. Additional PET/CT scans and brain MRIs classified 71 GGNs as stage IA, one as stage IIIA, and two as stage IV. However, surgery and additional diagnostic work-ups for abnormal findings from PET/CT scans classified 70 GGNs as stage IA, three as stage IB, and one as stage IIA. The chest CT scans did not differ from the combined modality of PET/CT scans and brain MRIs for the determination of the overall stage (94.6% vs. 90.5%; kappa value, 0.712). PET/CT scans in combination with brain MRIs have no additional benefit for the staging of patients with GGN lung adenocarcinoma before surgery.

  13. Patch-based generation of a pseudo CT from conventional MRI sequences for MRI-only radiotherapy of the brain

    DEFF Research Database (Denmark)

    Andreasen, Daniel; Van Leemput, Koen; Hansen, Rasmus H.

    2015-01-01

    Purpose: In radiotherapy (RT) based on magnetic resonance imaging (MRI) as the only modality, the information on electron density must be derived from the MRI scan by creating a so-called pseudo computed tomography (pCT). This is a nontrivial task, since the voxel-intensities in an MRI scan are n...... on conventional T1-weighted MRI sequences and without deformable registrations. In our evaluations, the method performed better than existing voxel-based and atlas-based methods and showed a promising potential for RT of the brain based only on MRI.......Purpose: In radiotherapy (RT) based on magnetic resonance imaging (MRI) as the only modality, the information on electron density must be derived from the MRI scan by creating a so-called pseudo computed tomography (pCT). This is a nontrivial task, since the voxel-intensities in an MRI scan...... are not uniquely related to electron density. To solve the task, voxel-based or atlas-based models have typically been used. The voxel-based models require a specialized dual ultrashort echo time MRI sequence for bone visualization and the atlas-based models require deformable registrations of conventional MRI...

  14. Evaluation of intrapleural contrast-enhanced abdominal pelvic CT-scan in detecting diaphragm injury in stable patients with thoraco-abdominal stab wound: a preliminary study.

    Science.gov (United States)

    Abbasy, Hamid Reza; Panahi, Farzad; Sefidbakht, Sepideh; Akrami, Majid; Paydar, Shahram; Mirhashemi, Sedighe; Bolandparvaz, Shahram; Asaadi, Kambiz; Salahi, Roohollah

    2012-09-01

    Many of the patients with thoraco-abdominal stab wound remain asymptomatic; in this regard, previous studies reported that 7-48% of asymptomatic patients had diaphragm injury (DI). Thoracoscopy or multidetector computed tomography (MDCT) scan is the best method to detect DI. We aimed to evaluate the role of CT scan with intrapleural contrast to rule out DI in stable thoraco-abdominal stab wounds. In a prospective study, we evaluated all haemodynamically stable patients with thoraco-abdominal stab wound, from October 2009 to 2010. Exclusion criteria included patients who needed emergency thoracotomy or laparotomy, those who were haemodynamically unstable and those with blunt trauma or gunshot injury. In the CT-scan department, 500 cc of diluted meglumine diatrozate was transfused into the pleural space via a chest tube and the CT scan was performed from the dome of the diaphragm to the pelvic cavity. In the second step, all patients were taken for thoracoscopy within 24h after admission. The CT-scan slide was considered positive if one of the following signs was found: (1) the diaphragm was obviously injured as seen in CT-scan slides and (2) contrast agent was seen in the peritoneal cavity. Sensitivity and specificity were calculated for CT scan and thoracoscopy. Four out of 40 patients had DI according to thoracoscopy. CT scan with intrapleural contrast predicted diaphragmatic injury correctly in all four patients. Considering thoracoscopy as the gold-standard method, the CT scan had two false-positive cases. The sensitivity of the intrapleural-contrast CT scan was 100% and its specificity was 94.4%. Our study showed that CT scan with intrapleural contrast can be an acceptable approach to rule out DI and limit the use of thoracoscopy for final diagnosis and repair of DI in cases with suspicious or positive CT-scan results, especially in trauma centres with high load of trauma patients and little accessible equipment. Copyright © 2011 Elsevier Ltd. All rights

  15. Interobserver variability in visual evaluation of thoracic CT scans and comparison with automatic computer measurements of CT lung density

    DEFF Research Database (Denmark)

    Winkler Wille, Mathilde Marie; Thomsen, Laura Hohwü; Dirksen, Asger

    2012-01-01

    in emphysema grading. However, the agreement with the CT lung density measurement was poor, indicating that the two types of evaluation represent different aspects of emphysema. Most likely, they should be seen as complementary rather than competitive evaluations. Future comparison with physiological tests......Introduction – Emphysema is defined by pathology, but is most precisely evaluated in vivo by computed tomography (CT). Aims – were to determine the reproducibility of visual evaluation of emphysema, i.e. the observer variability, and furthermore to compare the visual evaluations to automatic CT...... might elucidate the reason for differences and demonstrate the usefulness of these evaluations....

  16. Combined endeavor of Neutrosophic Set and Chan-Vese model to extract accurate liver image from CT scan.

    Science.gov (United States)

    Siri, Sangeeta K; Latte, Mrityunjaya V

    2017-11-01

    Many different diseases can occur in the liver, including infections such as hepatitis, cirrhosis, cancer and over effect of medication or toxins. The foremost stage for computer-aided diagnosis of liver is the identification of liver region. Liver segmentation algorithms extract liver image from scan images which helps in virtual surgery simulation, speedup the diagnosis, accurate investigation and surgery planning. The existing liver segmentation algorithms try to extort exact liver image from abdominal Computed Tomography (CT) scan images. It is an open problem because of ambiguous boundaries, large variation in intensity distribution, variability of liver geometry from patient to patient and presence of noise. A novel approach is proposed to meet challenges in extracting the exact liver image from abdominal CT scan images. The proposed approach consists of three phases: (1) Pre-processing (2) CT scan image transformation to Neutrosophic Set (NS) and (3) Post-processing. In pre-processing, the noise is removed by median filter. The "new structure" is designed to transform a CT scan image into neutrosophic domain which is expressed using three membership subset: True subset (T), False subset (F) and Indeterminacy subset (I). This transform approximately extracts the liver image structure. In post processing phase, morphological operation is performed on indeterminacy subset (I) and apply Chan-Vese (C-V) model with detection of initial contour within liver without user intervention. This resulted in liver boundary identification with high accuracy. Experiments show that, the proposed method is effective, robust and comparable with existing algorithm for liver segmentation of CT scan images. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. The value of whole-brain CT perfusion imaging and CT angiography using a 320-slice CT scanner in the diagnosis of MCI and AD patients.

    Science.gov (United States)

    Zhang, Bo; Gu, Guo-Jun; Jiang, Hong; Guo, Yi; Shen, Xing; Li, Bo; Zhang, Wei

    2017-06-02

    To validate the value of whole-brain computed tomography perfusion (CTP) and CT angiography (CTA) in the diagnosis of mild cognitive impairment (MCI) and Alzheimer's disease (AD). Whole-brain CTP and four-dimensional CT angiography (4D-CTA) images were acquired in 30 MCI, 35 mild AD patients, 35 moderate AD patients, 30 severe AD patients and 50 normal controls (NC). Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and correlation between CTP and 4D-CTA were analysed. Elevated CBF in the left frontal and temporal cortex was found in MCI compared with the NC group. However, TTP was increased in the left hippocampus in mild AD patients compared with NC. In moderate and severe AD patients, hypoperfusion was found in multiple brain areas compared with NC. Finally, we found that the extent of arterial stenosis was negatively correlated with CBF in partial cerebral cortex and hippocampus, and positively correlated with TTP in these areas of AD and MCI patients. Our findings suggest that whole-brain CTP and 4D-CTA could serve as a diagnostic modality in distinguishing MCI and AD, and predicting conversion from MCI based on TTP of left hippocampus. • Whole-brain perfusion using the full 160-mm width of 320 detector rows • Provide clinical experience of 320-row CT in cerebrovascular disorders of Alzheimer's disease • Initial combined 4D CTA-CTP data analysed perfusion and correlated with CT angiography • Whole-brain CTP and 4D-CTA have high value for monitoring MCI to AD progression • TTP in the left hippocampus may predict the transition from MCI to AD.

  18. Combined 18F-Fluoride and 18F-FDG PET/CT Scanning for Evaluation of Malignancy: Results of an International Multicenter Trial

    DEFF Research Database (Denmark)

    Iagaru, Andrei; Mittra, Erik; Mosci, Camila

    2012-01-01

    PET/CT examination for evaluation of cancer patients and compared it with separate 18F2 PET/CT and 18F-FDG PET/CT scans. Methods: One hundred fifteen participants with cancer were prospectively enrolled in an international multicenter trial evaluating 18F2 PET/CT, 18F-FDG PET/CT, and combined 18F2/18F......-FDG PET/CT. The 3 PET/CT scans were performed sequentially within 4 wk of one another for each patient. Results: 18F2/18FFDG PET/CT allowed for accurate interpretation of radiotracer uptake outside the skeleton, with findings similar to those of 18F-FDG PET/CT. In 19 participants, skeletal disease...

  19. Incorporating Radiology into Medical Gross Anatomy: Does the Use of Cadaver CT Scans Improve Students' Academic Performance in Anatomy?

    Science.gov (United States)

    Lufler, Rebecca S.; Zumwalt, Ann C.; Romney, Carla A.; Hoagland, Todd M.

    2010-01-01

    Radiological images show anatomical structures in multiple planes and may be effective for teaching anatomical spatial relationships, something that students often find difficult to master. This study tests the hypotheses that (1) the use of cadaveric computed tomography (CT) scans in the anatomy laboratory is positively associated with…

  20. The Use of CT Scan in Hemodynamically Stable Children with Blunt Abdominal Trauma : Look before You Leap

    NARCIS (Netherlands)

    Nellensteijn, David R.; Greuter, Marcel J.; el Moumni, Moustafa; Hulscher, Jan B.

    We set out to determine the diagnostic value of computed tomographic (CT) scans in relation to the radiation dose, tumor incidence, and tumor mortality by radiation for hemodynamically stable pediatric patients with blunt abdominal injury. We focused on the changes in management because of new

  1. Scatter radiation breast exposure during head CT: impact of scanning conditions and anthropometric parameters on shielded and unshielded breast dose

    Energy Technology Data Exchange (ETDEWEB)

    Klasic, B. [Hospital for pulmonary diseases, Zagreb (Croatia); Knezevic, Z.; Vekic, B. [Rudjer Boskovic Institute, Zagreb (Croatia); Brnic, Z.; Novacic, K. [Merkur Univ. Hospital, Zagreb (Croatia)

    2006-07-01

    Constantly increasing clinical requests for CT scanning of the head on our facility continue to raise concern regarding radiation exposure of patients, especially radiosensitive tissues positioned close to the scanning plane. The aim of our prospective study was to estimate scatter radiation doses to the breast from routine head CT scans, both with and without use of lead shielding, and to establish influence of various technical and anthropometric factors on doses using statistical data analysis. In 85 patient referred to head CT for objective medical reasons, one breast was covered with lead apron during CT scanning. Radiation doses were measured at skin of both breasts and over the apron simultaneously, by the use of thermo luminescent dosimeters. The doses showed a mean reduction by 37% due to lead shielding. After we statistically analyzed our data, we observed significant correlation between under-the-shield dose and values of technical parameters. We used multiple linear regression model to describe the relationships of doses to unshielded and shielded breast respectively, with anthropometric and technical factors. Our study proved lead shielding of the breast to be effective, easy to use and leading to a significant reduction in scatter dose. (author)

  2. Delayed post-surgical sepsis from Teflon felt: The diagnostic value of CT scanning, and a reminder for theatre staff

    Directory of Open Access Journals (Sweden)

    D Emby

    2011-06-01

    Full Text Available We report on 2 patients with surgical site infections following the inadvertent use of Teflon felt for haemostasis in elective and emergency surgery. CT scanning was superior to plain radiography in demonstrating the foreign bodies to enable planning of further surgical treatment.

  3. Reconstruction of a time-averaged midposition CT scan for radiotherapy planning of lung cancer patients using deformable registration

    NARCIS (Netherlands)

    Wolthaus, J. W. H.; Sonke, J. J.; van Herk, M.; Damen, E. M. F.

    2008-01-01

    PURPOSE: lower lobe lung tumors move with amplitudes of up to 2 cm due to respiration. To reduce respiration imaging artifacts in planning CT scans, 4D imaging techniques are used. Currently, we use a single (midventilation) frame of the 4D data set for clinical delineation of structures and

  4. The Role of Conventional Bronchoscopy in the Workup of Suspicious CT Scan Screen-Detected Pulmonary Nodules

    NARCIS (Netherlands)

    van't Westeinde, Susan C.; Horeweg, Nanda; Vernhout, Rene M.; Groen, Harry J. M.; Lammers, Jan-Willem J.; Weenink, Carla; Nackaerts, Kristiaan; Oudkerk, Matthijs; Mali, Willem; Thunnissen, Frederik B.; de Koning, Harry J.; van Klaveren, Rob J.

    Background: Up to 50% of the participants in CT scan lung cancer screening trials have at least one pulmonary nodule. To date, the role of conventional bronchoscopy in the workup of suspicious screen-detected pulmonary nodules is unknown. If a bronchoscopic evaluation could be eliminated, the

  5. The role of conventional bronchoscopy in the workup of suspicious CT scan screen-detected pulmonary nodules

    NARCIS (Netherlands)

    S.C. van 't Westeinde (Susan); N. Horeweg (Nanda); R. Vernhout (Rene); H.J.M. Groen (Henk); J.-W.J. Lammers (Jan-Willem); C. Weenink (Carla); K. Nackaerts (Kristiaan); M. Oudkerk (Matthijs); W.P. Mali (Willem); F.B.J.M. Thunnissen (Frederik); H.J. de Koning (Harry); R.J. van Klaveren (Rob)

    2012-01-01

    textabstractBackground: Up to 50% of the participants in CT scan lung cancer screening trials have at least one pulmonary nodule. To date, the role of conventional bronchoscopy in the workup of suspicious screen-detected pulmonary nodules is unknown. If a bronchoscopic evaluation could be

  6. Systematic analysis of biological and physical limitations of proton beam range verification with offline PET/CT scans

    NARCIS (Netherlands)

    Knopf, A; Parodi, K.; Bortfeld, Thomas; Shih, Helen A; Paganetti, Harald

    2009-01-01

    The clinical use of offline positron emission tomography/computed tomography (PET/CT) scans for proton range verification is currently under investigation at the Massachusetts General Hospital (MGH). Validation is achieved by comparing measured activity distributions, acquired in patients after

  7. Experiences of using a single post-contrast CT scan of the urinary tract after triphasic contrast injection

    Directory of Open Access Journals (Sweden)

    Phillip Carl Pretorius

    2011-12-01

    Full Text Available I was alerted to an article in Radiology Vol. 255 No. 2 (May 20101 by a colleague. The article, entitled ‘Kidney and urinary tract imaging: Triple-bolus multidetector CT urography as a one-stop shop – Protocol design, opacification, and image quality analysis’, clearly describes the technique, while the quotation below, from the article, summarises the findings: ‘We have shown that triple-bolus multidetector CT urography allowed visualization of renal parenchymal, excretory, and vascular contrast-enhancement phases in a single dose-efficient acquisition and provided sufficient opacification of the UUT, with simultaneous and adequate image quality of renal parenchyma and vascular anatomy.’ The main emphasis on this technique is to reduce the number of unnecessary CT scans when assessing the urinary tract. Our previous protocol for scanning the urinary tract for pathology included four phases: a pre-contrast, corticomedullary, nephrographic and delay excretory phase.

  8. CT scan evaluation of glenoid bone and pectoralis major tendon: interest in shoulder prosthesis

    Directory of Open Access Journals (Sweden)

    Obert Laurent

    2016-01-01

    Full Text Available Introduction: The shoulder arthroplasty brings satisfaction to patients in terms of quality of life and indolence. However whether anatomic implant or reverse, it does not escape from the loosening of the glenoid component. Moreover, optimal implantation is required to ensure the functional outcome without shortening of the arm. The purpose of this study is obtain CT scan evaluation of the glenoid bone stock in order to optimize glenoid component implantation and obtain a reference to determine optimal humeral component placement in case of humeral proximal fracture. Materials and methods: Between 2010 and 2011 we have analyzed 200 intact shoulder’s CT. We measured maximal and minimal width in the transverse plane of the glenoid, the distance from the pectoralis major (PM tendon to the humeral head, the greater tubercle, change of curvature and the anatomical neck. Results: Mean maximum width was 27.4 ± 3.4 mm and mean minimum width was 15.5 ± 2.8 mm. Distances between upper edge of PM tendon to: humeral head, greater tubercle, change of curvature and anatomical neck were respectively: 67.6 ± 9.98 mm, 57.8 ± 10.3 mm, 28.7 ± 9 mm, and 34.2 ± 9.7 mm. Conclusion: Our study has produced an assessment of glenoid bone stock for optimal positioning of the glenoid implant but also to obtain a reference to determine the ideal location of the humeral component in the case of proximal humerus fracture.

  9. Image quality of multiplanar reconstruction of pulmonary CT scans using adaptive statistical iterative reconstruction

    Science.gov (United States)

    Honda, O; Yanagawa, M; Inoue, A; Kikuyama, A; Yoshida, S; Sumikawa, H; Tobino, K; Koyama, M; Tomiyama, N

    2011-01-01

    Objective We investigated the image quality of multiplanar reconstruction (MPR) using adaptive statistical iterative reconstruction (ASIR). Methods Inflated and fixed lungs were scanned with a garnet detector CT in high-resolution mode (HR mode) or non-high-resolution (HR) mode, and MPR images were then reconstructed. Observers compared 15 MPR images of ASIR (40%) and ASIR (80%) with those of ASIR (0%), and assessed image quality using a visual five-point scale (1, definitely inferior; 5, definitely superior), with particular emphasis on normal pulmonary structures, artefacts, noise and overall image quality. Results The mean overall image quality scores in HR mode were 3.67 with ASIR (40%) and 4.97 with ASIR (80%). Those in non-HR mode were 3.27 with ASIR (40%) and 3.90 with ASIR (80%). The mean artefact scores in HR mode were 3.13 with ASIR (40%) and 3.63 with ASIR (80%), but those in non-HR mode were 2.87 with ASIR (40%) and 2.53 with ASIR (80%). The mean scores of the other parameters were greater than 3, whereas those in HR mode were higher than those in non-HR mode. There were significant differences between ASIR (40%) and ASIR (80%) in overall image quality (pASIR did not suppress the severe artefacts of contrast medium. Conclusion In general, MPR image quality with ASIR (80%) was superior to that with ASIR (40%). However, there was an increased incidence of artefacts by ASIR when CT images were obtained in non-HR mode. PMID:21081572

  10. The relationship between organ dose and patient size in tube current modulated adult thoracic CT scans

    Science.gov (United States)

    Khatonabadi, Maryam; Zhang, Di; Yang, Jeffrey; DeMarco, John J.; Cagnon, Chris C.; McNitt-Gray, Michael F.

    2012-03-01

    Recently published AAPM Task Group 204 developed conversion coefficients that use scanner reported CTDIvol to estimate dose to the center of patient undergoing fixed tube current body exam. However, most performed CT exams use TCM to reduce dose to patients. Therefore, the purpose of this study was to investigate the correlation between organ dose and a variety of patient size metrics in adult chest CT scans that use tube current modulation (TCM). Monte Carlo simulations were performed for 32 voxelized models with contoured lungs and glandular breasts tissue, consisting of females and males. These simulations made use of patient's actual TCM data to estimate organ dose. Using image data, different size metrics were calculated, these measurements were all performed on one slice, at the level of patient's nipple. Estimated doses were normalized by scanner-reported CTDIvol and plotted versus different metrics. CTDIvol values were plotted versus different metrics to look at scanner's output versus size. The metrics performed similarly in terms of correlating with organ dose. Looking at each gender separately, for male models normalized lung dose showed a better linear correlation (r2=0.91) with effective diameter, while female models showed higher correlation (r2=0.59) with the anterior-posterior measurement. There was essentially no correlation observed between size and CTDIvol-normalized breast dose. However, a linear relationship was observed between absolute breast dose and size. Dose to lungs and breasts were consistently higher in females with similar size as males which could be due to shape and composition differences between genders in the thoracic region.

  11. A CAD of fully automated colonic polyp detection for contrasted and non-contrasted CT scans.

    Science.gov (United States)

    Tulum, Gökalp; Bolat, Bülent; Osman, Onur

    2017-04-01

    Computer-aided detection (CAD) systems are developed to help radiologists detect colonic polyps over CT scans. It is possible to reduce the detection time and increase the detection accuracy rates by using CAD systems. In this paper, we aimed to develop a fully integrated CAD system for automated detection of polyps that yields a high polyp detection rate with a reasonable number of false positives. The proposed CAD system is a multistage implementation whose main components are: automatic colon segmentation, candidate detection, feature extraction and classification. The first element of the algorithm includes a discrete segmentation for both air and fluid regions. Colon-air regions were determined based on adaptive thresholding, and the volume/length measure was used to detect air regions. To extract the colon-fluid regions, a rule-based connectivity test was used to detect the regions belong to the colon. Potential polyp candidates were detected based on the 3D Laplacian of Gaussian filter. The geometrical features were used to reduce false-positive detections. A 2D projection image was generated to extract discriminative features as the inputs of an artificial neural network classifier. Our CAD system performs at 100% sensitivity for polyps larger than 9 mm, 95.83% sensitivity for polyps 6-10 mm and 85.71% sensitivity for polyps smaller than 6 mm with 5.3 false positives per dataset. Also, clinically relevant polyps ([Formula: see text]6 mm) were identified with 96.67% sensitivity at 1.12 FP/dataset. To the best of our knowledge, the novel polyp candidate detection system which determines polyp candidates with LoG filters is one of the main contributions. We also propose a new 2D projection image calculation scheme to determine the distinctive features. We believe that our CAD system is highly effective for assisting radiologist interpreting CT.

  12. Automatic transperineal ultrasound probe positioning based on CT scan for image guided radiotherapy

    Science.gov (United States)

    Camps, S. M.; Verhaegen, F.; Paiva Fonesca, G.; de With, P. H. N.; Fontanarosa, D.

    2017-03-01

    Image interpretation is crucial during ultrasound image acquisition. A skilled operator is typically needed to verify if the correct anatomical structures are all visualized and with sufficient quality. The need for this operator is one of the major reasons why presently ultrasound is not widely used in radiotherapy workflows. To solve this issue, we introduce an algorithm that uses anatomical information derived from a CT scan to automatically provide the operator with a patient-specific ultrasound probe setup. The first application we investigated, for its relevance to radiotherapy, is 4D transperineal ultrasound image acquisition for prostate cancer patients. As initial test, the algorithm was applied on a CIRS multi-modality pelvic phantom. Probe setups were calculated in order to allow visualization of the prostate and adjacent edges of bladder and rectum, as clinically required. Five of the proposed setups were reproduced using a precision robotic arm and ultrasound volumes were acquired. A gel-filled probe cover was used to ensure proper acoustic coupling, while taking into account possible tilted positions of the probe with respect to the flat phantom surface. Visual inspection of the acquired volumes revealed that clinical requirements were fulfilled. Preliminary quantitative evaluation was also performed. The mean absolute distance (MAD) was calculated between actual anatomical structure positions and positions predicted by the CT-based algorithm. This resulted in a MAD of (2.8±0.4) mm for prostate, (2.5±0.6) mm for bladder and (2.8±0.6) mm for rectum. These results show that no significant systematic errors due to e.g. probe misplacement were introduced.

  13. Cystic Fibrosis: Are Volumetric Ultra-Low-Dose Expiratory CT Scans Sufficient for Monitoring Related Lung Disease?

    DEFF Research Database (Denmark)

    Loeve, Martine; Lequin, Maarten H; Bruijne, Marleen de

    2009-01-01

    with CF aged 6–20 years (eight males, 12 females) underwent low-dose end-inspiratory CT and ultra-low-dose end-expiratory CT. Informed consent was obtained. Scans were randomized and scored by using the Brody-II CT scoring system to assess bronchiectasis, airway wall thickening, mucus plugging......-inspiratory and end-expiratory CT scores for Brody-II total score (ICC = 0.96), bronchiectasis (ICC = 0.98), airway wall thickening (ICC = 0.94), mucus plugging (ICC = 0.96), and opacities (ICC = 0.90). Intra- and interobserver agreement were good to very good (ICC range, 0.70–0.98). Bland-Altman plots showed...

  14. Association Between Airway Caliber Changes With Lung Inflation and Emphysema Assessed by Volumetric CT Scan in Subjects With COPD

    Science.gov (United States)

    Come, Carolyn E.; Ross, James C.; San José Estépar, Raúl; Han, MeiLan K.; Loring, Stephen H.; Silverman, Edwin K.; Washko, George R.

    2012-01-01

    Background: An increase in airway caliber (airway distensibility) with lung inflation is attenuated in COPD. Furthermore, some subjects have a decrease in airway caliber with lung inflation. We aimed to test the hypothesis that airway caliber increases are lower in subjects with emphysema-predominant (EP) compared with airway-predominant (AP) CT scan subtypes. Additionally, we compared clinical and CT scan features of subjects with (airway constrictors) and without a decrease in airway caliber. Methods: Based on GOLD (Global Initiative for Chronic Obstructive Lung Disease) stages and CT scan subtypes, we created a control group (n = 46) and the following matched COPD groups (n = 23 each): GOLD-2-AP, GOLD-2-EP, GOLD-4-AP, and GOLD-4-EP. From the CT scans of all 138 subjects, we measured emphysema, lung volumes, and caliber changes in the third and fourth airway generations of two bronchi. We expressed airway distensibility (ratio of airway lumen diameter change to lung volume change from end tidal breathing to full inspiration) as a global or lobar measure based on normalization by whole-lung or lobar volume changes. Results: Global distensibility in the third and fourth airway generations was significantly lower in the GOLD-2-EP and GOLD-4-EP groups than in control subjects. In GOLD-2 subjects, lobar distensibility of the right-upper-lobe fourth airway generation was significantly lower in those with EP than in those with AP. In multivariate analysis, emphysema was an independent determinant of global and lobar airway distensibility. Compared with nonconstrictors, airway constrictors experienced more dyspnea, were more hyperinflated, and had a higher percentage of emphysema. Conclusions: Distensibility of large- to medium-sized airways is reduced in subjects with an EP CT scan subtype. Emphysema seems to alter airway-parenchyma interdependence. Trial registry: ClinicalTrials.gov; No.: NCT00608764; URL: www.clinicaltrials.gov PMID:21940776

  15. Fibroelastic pseudotumor elastofibroma dorsi detected by 18F-FDG PET/CT scan and by postherapy radioiodine SPECT/CT.

    Science.gov (United States)

    Oporto, M; Cepa, F; Orta, N; Rubí, S; Navalón, H; Peña, C

    Radioiodine uptake in the thyroid tissue, metastasis of differentiated thyroid cancer (DTC), and in other tissues, depends on the expression of sodium-iodide symporter (NIS). Vascular permeability, effusions, inflammation, and other mechanisms may also play a role in the accumulation of radioactive iodine. A 63-year-old woman underwent radioiodine therapy, as well as a post-therapy whole-body scan, as she was suspected of having lung metastasis from thyroid carcinoma. The scan not only showed uptake at the lung metastasis but also a faint diffuse bilateral uptake in the posterior thorax. On SPECT/CT this uptake was located in a known Elastofibroma Dorsi (ED) previously diagnosed by contrast CT and viewed in a FDG PET/CT. The radioiodine uptake in ED, especially if typical, is not a diagnostic problem in SPECT/CT study, but can be misleading in a study limited to a few planar images, particularly if the uptake occurs asymmetrically, or ED is located in a unsuspected area. Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

  16. Clinical Indications and Impact on Management: Fourth and Subsequent Posttherapy Follow-up18F-FDG PET/CT Scans in Oncology Patients.

    Science.gov (United States)

    Taghipour, Mehdi; Marcus, Charles; Sheikhbahaei, Sara; Mena, Esther; Prasad, Shwetha; Jha, Abhinav K; Solnes, Lilja; Subramaniam, Rathan M

    2017-05-01

    The Centers for Medicare and Medicaid Services coverage includes 3 posttherapy 18 F-FDG PET/CT scans per patient and per tumor type. Any additional follow-up 18 F-FDG PET/CT scans will be reimbursed at the discretion of a local Medicare administrator, if deemed medically necessary. This study aimed to investigate common clinical indications for performing a fourth or additional follow-up 18 F-FDG PET/CT scans that could affect the management of patients. Methods: This was a retrospective institutional review of 433 oncology patients (203 men; mean age, 55 y), including a total of 1,659 fourth or subsequent follow-up PET/CT scans after completion of primary treatment. Twelve indications for performing a fourth or subsequent follow-up PET/CT scan were determined, and the impact of each of the 12 indications on patients' management was evaluated. Results: The primary tumors were breast cancer (92 patients, 426 scans), non-Hodgkin lymphoma (77 patients, 208 scans), Hodgkin disease (41 patients, 182 scans), colorectal cancer (70 patients, 286 scans), melanoma (69 patients, 271 scans), and lung cancer (84 patients, 286 scans). The indications were categorized in 4 groups: PET/CT for diagnosis of tumor recurrence (303/1,659, 18.3%), PET/CT before starting therapy for tumor recurrence (64/1,659, 3.9%), PET/CT to assess therapy response for tumor recurrence (507/1,659, 30.6%), and follow-up PET/CT after completion of treatment for tumor recurrence (785/1,659, 47.3%). Overall, fourth and subsequent follow-up 18 F-FDG PET/CT scans resulted in change in management in 31.6% of the scans (356 of 1,128) when the scans were obtained for medical necessities (indications 1-11), and in 5.6% of the scans (30/531) when the scans were obtained without any medical necessity (indication 12). Conclusion: The fourth and subsequent PET/CT scans obtained after completion of primary treatment led to a change in management in 31.6% of the scans when acquired for appropriate clinical reasons

  17. Investigating the minimum scan parameters required to generate free-breathing motion artefact-free fast-helical CT.

    Science.gov (United States)

    Thomas, David H; Tan, Jun; Neylon, Jack; Dou, Tai; O'Connell, Dylan; McNitt-Gray, Michael; Lee, Percy; Lamb, James; Low, Daniel A

    2018-02-01

    A recently proposed "5DCT" protocol uses deformable registration of free-breathing fast-helical CT scans to generate a breathing motion model. In order to allow accurate registration, free-breathing images are required to be free of doubling-artefacts, which arise when tissue motion is greater than scan speed. Using a unique set of digital phantoms based on patient data and verified with a motion phantom, this work identifies the minimum scanner parameters required to successfully generate free-breathing artefact-free fast-helical scans. A motion phantom and 5 patients were imaged 25 times under free-breathing conditions in alternating directions with a 64-slice CT scanner employing a low-dose fast-helical protocol. A series of high temporal resolution (0.1 s) 5DCT scan data sets was generated in each case. A simulated CT scanner was used to "image" each free-breathing data set. Various CT scanner detector widths and rotation times were simulated, and verified using the motion phantom results. Motion-induced artefacts were quantified in patient images using structural similarity maps to determine the similarity between axial slices. Increasing amounts of motion-induced artefacts were observed with increasing rotation times >0.2 s for 16 mm detector configuration. The current generation of 16-slice CT scanners, which are present in the majority of Radiation Oncology departments, are not capable of generating free-breathing sorting artefact-free images required for 5DCT. Advances in knowledge: A recently proposed "5DCT" protocol uses deformable registration of free-breathing fast-helical CT scans to generate a breathing motion model. In order to allow accurate registration, free-breathing images are required to be free of doubling-artefacts, which arise when tissue motion is greater than scan speed. The results suggest that the current generation of 16-slice CT scanners, present in the majority of Radiation Oncology departments, are not capable of generating

  18. Can experienced surgeons predict the additional value of a CT scan in patients with displaced intra-articular distal radius fractures?

    NARCIS (Netherlands)

    Kleinlugtenbelt, Y. V.; Madden, K.; Groen, S. R.; Ham, S. J.; Kloen, P.; Haverlag, R.; Simons, M. P.; Bhandari, M.; Goslings, J. C.; Scholtes, V. A. B.; Poolman, R. W.

    2017-01-01

    There are no clear guidelines when an additional CT scan should be obtained for the treatment of displaced intra-articular distal radius fractures (DRF). This study aimed to investigate whether surgeons can predict the usefulness of CT scans to facilitate choice of treatment plan and/or

  19. Interobserver variability in visual evaluation of thoracic CT scans and comparison with automatic computer measurements of CT lung density

    DEFF Research Database (Denmark)

    Winkler Wille, Mathilde Marie; Thomsen, Laura Hohwü; Dirksen, Asger

    2012-01-01

    Introduction – Emphysema is defined by pathology, but is most precisely evaluated in vivo by computed tomography (CT). Aims – were to determine the reproducibility of visual evaluation of emphysema, i.e. the observer variability, and furthermore to compare the visual evaluations to automatic CT...... information. The lung was segmented automatically by in-house developed computer software, and the percentage of pixels below -950 HU was used as a surrogate marker for emphysema. The observer variability, as well as the correlation with the lung density measurements, was analysed using Spearman’s rank...... in emphysema grading. However, the agreement with the CT lung density measurement was poor, indicating that the two types of evaluation represent different aspects of emphysema. Most likely, they should be seen as complementary rather than competitive evaluations. Future comparison with physiological tests...

  20. Sex determination from scapular length measurements by CT scans images in a Caucasian population.

    Science.gov (United States)

    Giurazza, F; Schena, E; Del Vescovo, R; Cazzato, R L; Mortato, L; Saccomandi, P; Paternostro, F; Onofri, L; Zobel, B Beomonte

    2013-01-01

    Together with race, stature and age, sex is a main component of the biological identity. Thanks to its proportional correlation with parts of the human body, sex can be evaluated form the skeleton. The most accurate approach to determine sex by bone size is based on os coxae or skull. After natural disaster their presence can never be guaranteed, therefore the development of methods of sex determination using other skeletal elements can result crucial. Herein, sexual dimorphism in the human scapula is used to develop a two-variable discriminant function for sex estimation. We have enrolled 100 males and 100 females who underwent thoracic CT scan evaluation and we have estimated two scapular diameters. The estimation has been carried out by analyzing images of the scapulae of each patient after three dimensional post-processing reconstructions. The two-variable function allows to obtain an overall accuracy of 88% on the calibration sample. Furthermore, we have employed the mentioned function on a collection of 10 individual test sample from the collection of the "Museo di Anatomia Umana di Firenze" of the Università degli Studi di Firenze; sex has been correctly predicted on 9 skeletons.

  1. A CT-scan database for the facial soft tissue thickness of Taiwan adults.

    Science.gov (United States)

    Chung, Ju-Hui; Chen, Hsiao-Ting; Hsu, Wan-Yi; Huang, Guo-Shu; Shaw, Kai-Ping

    2015-08-01

    Facial reconstruction is a branch of forensic anthropology used to assist in the identification of skeletal remains. The majority of facial reconstruction techniques use facial soft tissue depth chart data to recreate facial tissue on a skull or a model of a skull through the use of modeling clay. This study relied on 193 subjects selected from the Taiwanese population on the basis of age and gender to determine the average values of 32 landmarks, include midline and bilateral measures, by means of CT scans. The mean age of the subjects was 46.9±16.4 years, with a mean age of 43.8±16.6 for males and 49.9±15.8 for females respectively. There were 16 landmarks with statistically significant differences between male and female subjects, namely S, G, N, Na, Ph, Sd and Id in the midline portion, FE, LO, ZA and Sub M2 in the bilateral-right and left portion, and IM point in the bilateral-left portion (abbreviations adapted from Karen T. Taylor's work). The mean soft tissue depth was greater in males than in females, and there was significant difference between the right and left sides of the face in Za point. This study's findings were compared with those of Bulut et al. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Upper airway finding on CT scan with and without nasal CPAP in obstructive sleep apnea patients

    Energy Technology Data Exchange (ETDEWEB)

    Akashiba, Tsuneto; Sasaki, Iwao; Kurashina, Keiji; Yoshizawa, Takayuki; Otsuka, Kenzo; Horie, Takashi (Nihon Univ., Tokyo (Japan). School of Medicine)

    1991-04-01

    The area of upper airway (from the nasopharynx to the hypopharynx) was measured by means of computed tomography (CT) scan in 15 confirmed cases of obstructive sleep apnea (OSA) and in 4 normal controls while they were awake. The minimum cross-sectional area (MA) of the upper airway was 14.7+-20.0 mm{sup 2} in OSA patients and 80.0+-33.1 mm{sup 2} in normal controls and the difference was statistically significant (p<0.01). In OSA patients, MA did not correlate with age, body weight, apnea index, desaturation index, mean nadir-SO{sub 2} and lowest SO{sub 2}. MA was also measured with OSA patients while nasal continuous positive airway pressure (NCPAP) of 10 cmH{sub 2}O was applied and it was found that MA was significantly widened when NCPAP therapy was performed. We conclude that upper airway narrowing is consistent finding in OSA patients but the degree of narrowing does not correlate with parameters of apnea and gas exchange during sleep, and NCPAP is effective to widen the area of upper airway in OSA patients. (author).

  3. The first ant-termite syninclusion in amber with CT-scan analysis of taphonomy.

    Directory of Open Access Journals (Sweden)

    David Coty

    Full Text Available We describe here a co-occurrence (i.e. a syninclusion of ants and termites in a piece of Mexican amber (Totolapa deposit, Chiapas, whose importance is two-fold. First, this finding suggests at least a middle Miocene antiquity for the modern, though poorly documented, relationship between Azteca ants and Nasutitermes termites. Second, the presence of a Neivamyrmex army ant documents an in situ raiding behaviour of the same age and within the same community, confirmed by the fact that the army ant is holding one of the termite worker between its mandibles and by the presence of a termite with bitten abdomen. In addition, we present how CT-scan imaging can be an efficient tool to describe the topology of resin flows within amber pieces, and to point out the different states of preservation of the embedded insects. This can help achieving a better understanding of taphonomical processes, and tests ethological and ecological hypotheses in such complex syninclusions.

  4. Application of single- and dual-energy CT brain tissue segmentation to PET monitoring of proton therapy

    Science.gov (United States)

    Berndt, Bianca; Landry, Guillaume; Schwarz, Florian; Tessonnier, Thomas; Kamp, Florian; Dedes, George; Thieke, Christian; Würl, Matthias; Kurz, Christopher; Ganswindt, Ute; Verhaegen, Frank; Debus, Jürgen; Belka, Claus; Sommer, Wieland; Reiser, Maximilian; Bauer, Julia; Parodi, Katia

    2017-03-01

    The purpose of this work was to evaluate the ability of single and dual energy computed tomography (SECT, DECT) to estimate tissue composition and density for usage in Monte Carlo (MC) simulations of irradiation induced β + activity distributions. This was done to assess the impact on positron emission tomography (PET) range verification in proton therapy. A DECT-based brain tissue segmentation method was developed for white matter (WM), grey matter (GM) and cerebrospinal fluid (CSF). The elemental composition of reference tissues was assigned to closest CT numbers in DECT space (DECTdist). The method was also applied to SECT data (SECTdist). In a validation experiment, the proton irradiation induced PET activity of three brain equivalent solutions (BES) was compared to simulations based on different tissue segmentations. Five patients scanned with a dual source DECT scanner were analyzed to compare the different segmentation methods. A single magnetic resonance (MR) scan was used for comparison with an established segmentation toolkit. Additionally, one patient with SECT and post-treatment PET scans was investigated. For BES, DECTdist and SECTdist reduced differences to the reference simulation by up to 62% when compared to the conventional stoichiometric segmentation (SECTSchneider). In comparison to MR brain segmentation, Dice similarity coefficients for WM, GM and CSF were 0.61, 0.67 and 0.66 for DECTdist and 0.54, 0.41 and 0.66 for SECTdist. MC simulations of PET treatment verification in patients showed important differences between DECTdist/SECTdist and SECTSchneider for patients with large CSF areas within the treatment field but not in WM and GM. Differences could be misinterpreted as PET derived range shifts of up to 4 mm. DECTdist and SECTdist yielded comparable activity distributions, and comparison of SECTdist to a measured patient PET scan showed improved agreement when compared to SECTSchneider. The agreement between predicted and measured PET

  5. False-positive 18-fluorodeoxyglucose positron emission tomography–computed tomography (FDG PET/CT scans mimicking malignancies

    Directory of Open Access Journals (Sweden)

    Zehra Yasar

    2015-02-01

    Full Text Available Aim 18-Fluorodeoxyglucose (FDG positron emission tomography–computed tomography (PET/CT is an imaging modality that is often used to help differentiate benign from malignant pulmonary lesions and it has been shown to be more efficacious than conventional chest computed tomography (CT. However, some benign lesions may also show increased metabolic activity which can lead to false-positive PET findings. We aim to illustrate false positive findings of PET scan that simulate lung cancer in a variety of diseases. Methods Patients referred to Yedikule Chest Diseases and Surgery Teaching and Research Hospital with increased FDG uptake for which histological results were available over a 2-year period (2013-2014 were reviewed. Seven patients with false-positive PET/CT findings were reported in this study. Results The majority of lesions showing increased metabolic activity were due to malignant diseases. However, increased 18 F-FDG uptake was also seen in benign lesions such as active pulmonary inflammation or infection, granulomatous processes and fibrotic lesions. Conclusion. The integration of clinical history, morphologic findings of lesions on the CT component, and metabolic activities of PET/CT scan can help reduce false interpretations. Interventional procedures.

  6. Automatic identification of IASLC-defined mediastinal lymph node stations on CT scans using multi-atlas organ segmentation

    Science.gov (United States)

    Hoffman, Joanne; Liu, Jiamin; Turkbey, Evrim; Kim, Lauren; Summers, Ronald M.

    2015-03-01

    Station-labeling of mediastinal lymph nodes is typically performed to identify the location of enlarged nodes for cancer staging. Stations are usually assigned in clinical radiology practice manually by qualitative visual assessment on CT scans, which is time consuming and highly variable. In this paper, we developed a method that automatically recognizes the lymph node stations in thoracic CT scans based on the anatomical organs in the mediastinum. First, the trachea, lungs, and spines are automatically segmented to locate the mediastinum region. Then, eight more anatomical organs are simultaneously identified by multi-atlas segmentation. Finally, with the segmentation of those anatomical organs, we convert the text definitions of the International Association for the Study of Lung Cancer (IASLC) lymph node map into patient-specific color-coded CT image maps. Thus, a lymph node station is automatically assigned to each lymph node. We applied this system to CT scans of 86 patients with 336 mediastinal lymph nodes measuring equal or greater than 10 mm. 84.8% of mediastinal lymph nodes were correctly mapped to their stations.

  7. 18F-DOPA PET/CT and 68Ga-DOTANOC PET/CT scans as diagnostic tools in focal congenital hyperinsulinism: a blinded evaluation.

    Science.gov (United States)

    Christiansen, Charlotte Dahl; Petersen, Henrik; Nielsen, Anne Lerberg; Detlefsen, Sönke; Brusgaard, Klaus; Rasmussen, Lars; Melikyan, Maria; Ekström, Klas; Globa, Evgenia; Rasmussen, Annett Helleskov; Hovendal, Claus; Christesen, Henrik Thybo

    2018-02-01

    Focal congenital hyperinsulinism (CHI) is curable by surgery, which is why identification of the focal lesion is crucial. We aimed to determine the use of 18F-fluoro-dihydroxyphenylalanine (18F-DOPA) PET/CT vs. 68Ga-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic-acid-1-Nal3-octreotide (68Ga-DOTANOC) PET/CT as diagnostic tools in focal CHI. PET/CT scans of children with CHI admitted to Odense University Hospital between August 2005 and June 2016 were retrospectively evaluated visually and by their maximal standardized uptake values (SUVmax) by two independent examiners, blinded for clinical, surgical and pathological data. Pancreatic histology was used as the gold standard. For patients without surgery, the genetic profile served as the gold standard. Fifty-five CHI patients were examined by PET/CT (18F-DOPA n = 53, 68Ga-DOTANOC n = 18). Surgery was performed in 34 patients, no surgery in 21 patients. Fifty-one patients had a classifiable outcome, either by histology (n = 33, 22 focal lesions, 11 non-focal) or by genetics (n = 18, all non-focal). The predictive performance of 18F-DOPA PET/CT to identify focal CHI was identical by visual- and cut-off-based evaluation: sensitivity (95% CI) of 1 (0.85-1); specificity of 0.96 (0.82-0.99). The optimal 18F-DOPA PET SUVmax ratio cut-off was 1.44 and the optimal 68Ga-DOTANOC PET SUVmax cut-off was 6.77 g/ml. The area under the receiver operating curve was 0.98 (0.93-1) for 18F-DOPA PET vs. 0.71 (0.43-0.95) for 68Ga-DOTANOC PET (p PET/CT and 68Ga-DOTANOC PET/CT, respectively. 18F-DOPA PET/CT was excellent in predicting focal CHI and superior compared to 68Ga-DOTANOC PET/CT. Further use of 68GA-DOTANOC PET/CT in predicting focal CHI is discouraged.

  8. Patient Alignment Estimation in Six Degrees of Freedom Using a CT-scan and a Single X-ray Image

    Science.gov (United States)

    Selby, B. P.; Sakas, G.; Walter, S.; Groch, W.-D.; Stilla, U.

    Particle beam treatment allows accurate dose delivery onto carcinogen tissue. The reachable accuracy is limited by patient alignment errors relative to the beam source. Errors can be corrected manually or by automatic comparison of two X-ray images to a CT-scan but correction mostly does not cover all degrees of freedom (DoF). In this contribution we present a solution that makes use of one X-ray image and computes full 6 DoF alignment correction by gray value based comparison to a CT. By using regions of interest, we are able to increase performance and reliability.

  9. Ribbon scanning confocal for high-speed high-resolution volume imaging of brain.

    Directory of Open Access Journals (Sweden)

    Alan M Watson

    Full Text Available Whole-brain imaging is becoming a fundamental means of experimental insight; however, achieving subcellular resolution imagery in a reasonable time window has not been possible. We describe the first application of multicolor ribbon scanning confocal methods to collect high-resolution volume images of chemically cleared brains. We demonstrate that ribbon scanning collects images over ten times faster than conventional high speed confocal systems but with equivalent spectral and spatial resolution. Further, using this technology, we reconstruct large volumes of mouse brain infected with encephalitic alphaviruses and demonstrate that regions of the brain with abundant viral replication were inaccessible to vascular perfusion. This reveals that the destruction or collapse of large regions of brain micro vasculature may contribute to the severe disease caused by Venezuelan equine encephalitis virus. Visualization of this fundamental impact of infection would not be possible without sampling at subcellular resolution within large brain volumes.

  10. Brain CT and MRI findings of a long-term case of subacute sclerosing panencephalitis

    Energy Technology Data Exchange (ETDEWEB)

    Aoshiba, Kazunori; Ota, Kohei; Komatsuzaki, Satoshi; Kobayashi, Itsuro; Maruyama, Shoichi

    1987-11-01

    Our study involved a long-term case (ten years) of subacute sclerosing panencephalitis. The case began with a 23 year-old experiencing visual deterioration. During the course of his illness, amnesia, autism and abnormal behavior were observed without any myoclonus. On the electroencephalogram, periodic synclonous discharge was shown in the early stage of his illness and subsequently disappeared. The brain CT and the MRI disclosed diffuse lesions in both cortical and subcortical areas of the cerebral hemispheres. The location and spread of lesions were more clearly revealed by the MRI than the brain CT. These findings suggest that the MRI is more useful than the brain CT in the diagnosis of subacute sclerosing panencephalitis.

  11. ''Routine'' brain CT in psychiatric patients - does it make sense?; ''Routine''-Schaedel-CT in der psychiatrischen Diagnostik

    Energy Technology Data Exchange (ETDEWEB)

    Pickuth, D.; Heywang-Koebrunner, S.H.; Spielmann, R.P. [Martin-Luther-Universitaet Halle-Wittenberg, Halle (Germany). Klinik und Poliklinik fuer Diagnostische Radiologie

    1999-11-01

    Purpose: To prospectively assess the spectrum of brain CT findings in psychiatric patients and to determine the number of patients that had an underlying cause for the symptoms. Patients and methods: Over a period of six months, 142 patients (78 males, 64 females; median age 61 [18-91] years) were referred for CT brain scans. Their scans were reviewed, along with the clinical information that was provided in the request form. All the hard copies were reviewed to assess areas of ischaemia, infarction, atrophy, tumours, and haematomas. The majority of requests were to exclude vascular event or space-occupying lesions. Clinical indications included mood disorders (depression, mania), schizophrenic disorders, dementia, personality and behavioural disorders. Results: 31 (22%) were normal. 111 (78%) had varying degrees of ischaemia, infarction and cerebral/cerebellar atrophy. 7 (4.9%) had space-occupying lesions which included two gliomas and five meningiomas. There were two chronic subdural haematomas and one arteriovenous malformation. Conclusion: 1. In our series, pathologic findings in 'routine' brain CT's were encountered in 78%. 2. The incidence of brain tumours was 4.9%, compared with 0.00005% of the general population. 3. CT scanning in psychiatric patients is cost-effective and especially indicated when there is an atypical presentation, or inadequate response to standard treatment. (orig.) [German] Hintergrund: Bei psychiatrischen Patienten wird vielerorts routinemaessig eine kraniale Computertomographie (CCT) durchgefuehrt. Ob der Nutzen die Kosten rechtfertigt, wurde im Rahmen einer Prospektivstudie untersucht. Patienten und Methode: In einem Zeitraum von 6 Monaten wurde bei 142 psychiatrischen Patienten (78 Maenner, 64 Frauen, 18-91 Jahre, Median 61 Jahre) ein CCT angefertigt. Die Untersuchung erfolgt nativ in 5-mm-Schichtdicke, bei klinischem Verdacht auf eine intrakraniale Raumforderung auch kontrastverstaerkt. Ueberweisungsdiagnosen waren v

  12. Development and validation of a brain maturation index using longitudinal neuroanatomical scans.

    Science.gov (United States)

    Cao, Bo; Mwangi, Benson; Hasan, Khader M; Selvaraj, Sudhakar; Zeni, Cristian P; Zunta-Soares, Giovana B; Soares, Jair C

    2015-08-15

    Major psychiatric disorders are increasingly being conceptualized as 'neurodevelopmental', because they are associated with aberrant brain maturation. Several studies have hypothesized that a brain maturation index integrating patterns of neuroanatomical measurements may reliably identify individual subjects deviating from a normative neurodevelopmental trajectory. However, while recent studies have shown great promise in developing accurate brain maturation indices using neuroimaging data and multivariate machine learning techniques, this approach has not been validated using a large sample of longitudinal data from children and adolescents. T1-weighted scans from 303 healthy subjects aged 4.88 to 18.35years were acquired from the National Institute of Health (NIH) pediatric repository (http://www.pediatricmri.nih.gov). Out of the 303 subjects, 115 subjects were re-scanned after 2years. The least absolute shrinkage and selection operator algorithm (LASSO) was 'trained' to integrate neuroanatomical changes across chronological age and predict each individual's brain maturity. The resulting brain maturation index was developed using first-visit scans only, and was validated using second-visit scans. We report a high correlation between the first-visit chronological age and brain maturation index (r=0.82, mean absolute error or MAE=1.69years), and a high correlation between the second-visit chronological age and brain maturation index (r=0.83, MAE=1.71years). The brain maturation index captured neuroanatomical volume changes between the first and second visits with an MAE of 0.27years. The brain maturation index developed in this study accurately predicted individual subjects' brain maturation longitudinally. Due to its strong clinical potentials in identifying individuals with an abnormal brain maturation trajectory, the brain maturation index may allow timely clinical interventions for individuals at risk for psychiatric disorders. Copyright © 2015 Elsevier Inc

  13. Computed tomographic (CT) study of the brains of 357 elderly demented patients. Clinical usefulness of CT measurements of brain atrophy and its correlation with mental assessment

    Energy Technology Data Exchange (ETDEWEB)

    Kono, Kazuhiko; Endo, Hidetoshi; Yamamoto, Takayuki; Kuzuya, Fumio

    1988-05-01

    It is well known that there is some limitation in the diagnostic effectiveness of brain computed tomography (CT) of dementia. Some investigators suggested certain correlation between brain atrophy and degree of psychological imparement in demented patients, but others did not agree with these suggestions. Authors have felt that the number of samples is very important in statistical analyses, thus they collected a great number of appropriate samples of dementia: that is, 59 of Alzheimer disease (AD), 120 of senile dementia of Alzheimer type (SDAT) and 178 of vascular dementia (VD), and compared these CT findings with those of 100 non-demented people. Firstly, we observed no relation between aging and brain atrophy in any type of dementia while there was a certain relation in non-demented people. Secondly, the female brain could easily become atrophic physiologically and was more severely atrophic in case of dementia compared with the male brain. Thirdly, it was impossible to differentiate SDAT from VD only by measuring values of dilatation of ventricles (maximum width of the third ventricle and cella media index) and sylvian fissures (''sylvian index''). Finally, it was observed that there was deep relation between the results of clinical assessments and the degree of brain atrophy in SDAT, because individual specificity in the type of atrophy was not variable in this type of dementia. Moreover all functions: that is, motor, intellectual, and emotional functions in SDAT patients, were impaired in the same degree respectively. From these results, authors could know many available characteristics of atrophy in the brains of demented patients through the following easy methods of measurement: linear measure method and ventricular-brain method, because we could analyse a sufficient number of samples.

  14. Value and clinical application of orthopedic metal artifact reduction algorithm in CT scans after orthopedic metal implantation

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yi; Pan, Shinong; Zhao, Xudong; Guo, Wenli; He, Ming; Guo, Qiyong [Shengjing Hospital of China Medical University, Shenyang (China)

    2017-06-15

    To evaluate orthopedic metal artifact reduction algorithm (O-MAR) in CT orthopedic metal artifact reduction at different tube voltages, identify an appropriate low tube voltage for clinical practice, and investigate its clinical application. The institutional ethical committee approved all the animal procedures. A stainless-steel plate and four screws were implanted into the femurs of three Japanese white rabbits. Preoperative CT was performed at 120 kVp without O-MAR reconstruction, and postoperative CT was performed at 80–140 kVp with O-MAR. Muscular CT attenuation, artifact index (AI) and signal-to-noise ratio (SNR) were compared between preoperative and postoperative images (unpaired t test), between paired O-MAR and non-O-MAR images (paired Student t test) and among different kVp settings (repeated measures ANOVA). Artifacts' severity, muscular homogeneity, visibility of inter-muscular space and definition of bony structures were subjectively evaluated and compared (Wilcoxon rank-sum test). In the clinical study, 20 patients undertook CT scan at low kVp with O-MAR with informed consent. The diagnostic satisfaction of clinical images was subjectively assessed. Animal experiments showed that the use of O-MAR resulted in accurate CT attenuation, lower AI, better SNR, and higher subjective scores (p < 0.010) at all tube voltages. O-MAR images at 100 kVp had almost the same AI and SNR as non-O-MAR images at 140 kVp. All O-MAR images were scored ≥ 3. In addition, 95% of clinical CT images performed at 100 kVp were considered satisfactory. O-MAR can effectively reduce orthopedic metal artifacts at different tube voltages, and facilitates low-tube-voltage CT for patients with orthopedic metal implants.

  15. A combined MR and CT study for precise quantitative analysis of the avian brain

    Science.gov (United States)

    Jirak, Daniel; Janacek, Jiri; Kear, Benjamin P.

    2015-10-01

    Brain size is widely used as a measure of behavioural complexity and sensory-locomotive capacity in avians but has largely relied upon laborious dissections, endoneurocranial tissue displacement, and physical measurement to derive comparative volumes. As an alternative, we present a new precise calculation method based upon coupled magnetic resonance (MR) imaging and computed tomography (CT). Our approach utilizes a novel interactive Fakir probe cross-referenced with an automated CT protocol to efficiently generate total volumes and surface areas of the brain tissue and endoneurocranial space, as well as the discrete cephalic compartments. We also complemented our procedures by using sodium polytungstate (SPT) as a contrast agent. This greatly enhanced CT applications but did not degrade MR quality and is therefore practical for virtual brain tissue reconstructions employing multiple imaging modalities. To demonstrate our technique, we visualized sex-based brain size differentiation in a sample set of Ring-necked pheasants (Phasianus colchicus). This revealed no significant variance in relative volume or surface areas of the primary brain regions. Rather, a trend towards isometric enlargement of the total brain and endoneurocranial space was evidenced in males versus females, thus advocating a non-differential sexually dimorphic pattern of brain size increase amongst these facultatively flying birds.

  16. The value of whole-brain CT perfusion imaging and CT angiography using a 320-slice CT scanner in the diagnosis of MCI and AD patients

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Bo; Gu, Guo-jun; Jiang, Hong; Guo, Yi [Medical School of Tongji University, Department of Medical Imaging, Tongji Hospital, Shanghai (China); Shen, Xing [Traditional Chinese Hospital, Department of Radiology, Kun Shan, Jiangsu Province (China); Li, Bo; Zhang, Wei [Medical School of Jiaotong University, Department of Medical Imaging, Renji Hospital, Shanghai (China)

    2017-11-15

    To validate the value of whole-brain computed tomography perfusion (CTP) and CT angiography (CTA) in the diagnosis of mild cognitive impairment (MCI) and Alzheimer's disease (AD). Whole-brain CTP and four-dimensional CT angiography (4D-CTA) images were acquired in 30 MCI, 35 mild AD patients, 35 moderate AD patients, 30 severe AD patients and 50 normal controls (NC). Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), time to peak (TTP), and correlation between CTP and 4D-CTA were analysed. Elevated CBF in the left frontal and temporal cortex was found in MCI compared with the NC group. However, TTP was increased in the left hippocampus in mild AD patients compared with NC. In moderate and severe AD patients, hypoperfusion was found in multiple brain areas compared with NC. Finally, we found that the extent of arterial stenosis was negatively correlated with CBF in partial cerebral cortex and hippocampus, and positively correlated with TTP in these areas of AD and MCI patients. Our findings suggest that whole-brain CTP and 4D-CTA could serve as a diagnostic modality in distinguishing MCI and AD, and predicting conversion from MCI based on TTP of left hippocampus. (orig.)

  17. Evaluation of a pulmonary strain model by registration of dynamic CT scans

    Science.gov (United States)

    Pomeroy, Marc; Liang, Zhengrong; Brehm, Anthony

    2017-03-01

    Idiopathic pulmonary fibrosis (IPF) is a chronic fibrotic lung disease that develops in adults without any known cause. It is an interstitial lung disease in which the lung tissue becomes scarred and stiffens, ultimately leading to respiratory failure. This disease currently has no cure with limited treatment options, leading to an average survival time of 3-5 years after diagnosis. In this paper we employ a mathematical model simulating the lung parenchyma as hexagons with elastic forces applied to connecting vertices and opposing vertices. Using an image registration algorithm, we obtain trajectories of 4D-CT scans of a healthy patient, and one suffering from IPF. Converting the image trajectories into a hexagonal lattice, we fit the model parameters to match the respiratory motion seen for both patients across multiple image slices. We found the model could decently describe the healthy lung slices, with a minimum average error between corresponding vertices to be 1.66 mm. For the fibrotic lung slices the model was less accurate, maintaining a higher average error across all slices. Using the optimized parameters, we apply the forces predicted from the model using the image trajectory positions for each phase. Although the error is large, the spring constant values determined for the fibrotic patient were not as high as we expected, and more often than not determined to be lower than corresponding healthy lung slices. However, the net force distribution for some of those slices was still found to be greater than the healthy lung counterparts. Other modifications to the model, including additional directional components and which vertices were receiving with the limited sample size available, a clear distinction between the healthy and fibrotic lung cannot yet be made by this model.

  18. Multidrug resistant tuberculosis versus non-tuberculous mycobacterial infections: a CT-scan challenge

    Energy Technology Data Exchange (ETDEWEB)

    Kahkouee, Shahram; Esmi, Elham; Moghadam, Azadeh; Karam, Mehrdad Bakhshayesh; Mosadegh, Leila; Salek, Solmaz; Tabarsi, Payam, E-mail: bestlala@yahoo.com [Chronic Respiratory Disease Research Center, NRITLD, Masih Daneshvari Hospital, Shahid Beheshti University of Medical Science, Tehran (Iran, Islamic Republic of)

    2013-03-15

    Introduction: clinical, laboratory and imaging findings in patients with multidrug resistant tuberculosis (MDR-TB) and non-tuberculosis mycobacterium (NTM) are similar, and the majority of these patients present with positive smear for Acid Fast Bacilli (ADB) and no response to first line anti-TB treatment, so sputum culture and PCR are necessary, especially in NTM. Objective: In this study we evaluate more details of imaging findings to help earlier diagnosis of pathogens. Materials and methods: 66 patients with positive smear for AFB and no response to first line anti-TB drugs were divided into two groups by PCR and culture: MDR-TB (43 patients) and NTM (23 patients). Age, sex, history of anti-TB treatment, smoking and CT-scan findings (parenchymal, pleural and mediastinal variables) by details and lobar distribution were analyzed. Results: mean age of NTM patients was slightly higher (52 versus 45) and there is no significant difference in sex and smoking. In MDR-TB group, history of anti-TB treatment and evidence of chronic pulmonary disease such as calcified and fibrodestructed parenchyma, volume loss and pleural thickening were higher significantly. Cavities in MDR-TB were thick wall in the background of consolidation, while NTM cavities were more thin-walled with adjacent satellite nodules in same segment or lobe. Prevalence of bronchiectasis was similar in both groups, while bronchiectasis in MDR-TB group was in fibrobronchiectatic background in upper lobes, and in NTM group the distribution was more uniform with slightly middle lobes predominance. Prevalence and distribution of nodular infiltrations were similar more in Tree in Buds and scattered pattern. Calcified or non-calcified lymph nodes and also pleural changes were more frequent in MDR-TB but prevalence of lymphadenopathy was mildly higher in NTM. (author)

  19. Atlas ranking and selection for automatic segmentation of the esophagus from CT scans

    Science.gov (United States)

    Yang, Jinzhong; Haas, Benjamin; Fang, Raymond; Beadle, Beth M.; Garden, Adam S.; Liao, Zhongxing; Zhang, Lifei; Balter, Peter; Court, Laurence

    2017-12-01

    In radiation treatment planning, the esophagus is an important organ-at-risk that should be spared in patients with head and neck cancer or thoracic cancer who undergo intensity-modulated radiation therapy. However, automatic segmentation of the esophagus from CT scans is extremely challenging because of the structure’s inconsistent intensity, low contrast against the surrounding tissues, complex and variable shape and location, and random air bubbles. The goal of this study is to develop an online atlas selection approach to choose a subset of optimal atlases for multi-atlas segmentation to the delineate esophagus automatically. We performed atlas selection in two phases. In the first phase, we used the correlation coefficient of the image content in a cubic region between each atlas and the new image to evaluate their similarity and to rank the atlases in an atlas pool. A subset of atlases based on this ranking was selected, and deformable image registration was performed to generate deformed contours and deformed images in the new image space. In the second phase of atlas selection, we used Kullback–Leibler divergence to measure the similarity of local-intensity histograms between the new image and each of the deformed images, and the measurements were used to rank the previously selected atlases. Deformed contours were overlapped sequentially, from the most to the least similar, and the overlap ratio was examined. We further identified a subset of optimal atlases by analyzing the variation of the overlap ratio versus the number of atlases. The deformed contours from these optimal atlases were fused together using a modified simultaneous truth and performance level estimation algorithm to produce the final segmentation. The approach was validated with promising results using both internal data sets (21 head and neck cancer patients and 15 thoracic cancer patients) and external data sets (30 thoracic patients).

  20. Atlas ranking and selection for automatic segmentation of the esophagus from CT scans.

    Science.gov (United States)

    Yang, Jinzhong; Haas, Benjamin; Fang, Raymond; Beadle, Beth B; Garden, Adam S; Liao, Zhongxing; Zhang, Lifei; Balter, Peter A; Court, Laurence E

    2017-10-19

    In radiation treatment planning, the esophagus is an important organ-at-risk that should be spared in patients with head and neck cancer or thoracic cancer who undergo intensity-modulated radiation therapy. However, automatic segmentation of the esophagus from CT scans is extremely challenging because of the structure's inconsistent intensity, low contrast against the surrounding tissues, complex and variable shape and location, and random air bubbles. The goal of this study is to develop an online atlas selection approach to choose a subset of optimal atlases for multi-atlas segmentation to delineate esophagus automatically. We performed atlas selection in 2 phases. In the first phase, we used the correlation coefficient of the image content in a cubic region between each atlas and the new image to evaluate their similarity and to rank the atlases in an atlas pool. A subset of atlases based on this ranking was selected, and deformable image registration was performed to generate deformed contours and deformed images in the new image space. In the second phase of atlas selection, we used Kullback-Leibler divergence to measure the similarity of local-intensity histograms between the new image and each of the deformed images, and the measurements were used to rank the previously selected atlases. Deformed contours were overlapped sequentially, from the most to the least similar, and the overlap ratio was examined. We further identified a subset of optimal atlases by analyzing the variation of the overlap ratio versus the number of atlases. The deformed contours from these optimal atlases were fused together using a modified Simultaneous Truth and Performance Level Estimation algorithm to produce the final segmentation. The approach was validated with promising results using 21 head and neck cancer patients and 15 thoracic cancer patients. © 2017 Institute of Physics and Engineering in Medicine.

  1. Diffusing capacity for carbon monoxide correlates best with tissue volume from quantitative CT scanning analysis.

    Science.gov (United States)

    Barjaktarevic, Igor; Springmeyer, Steven; Gonzalez, Xavier; Sirokman, William; Coxson, Harvey O; Cooper, Christopher B

    2015-06-01

    Quantitative analysis of high-resolution chest CT scan (QCT) is an established method for determining the severity and distribution of lung parenchymal destruction inpatients with emphysema. Diffusing capacity of the lung for carbon monoxide (D(LCO)) is a traditional physiologic measure of emphysema severity and is probably influenced more by destruction of the alveolar capillary bed than by membrane diffusion per se. We reasoned that D(LCO) should correlate with tissue volume from QCT. A total of 460 patients with upper-lobe-predominant emphysema were enrolled in the study. Th e mean (SD) of percent predicted values for FEV 1 , total lung capacity, and D(LCO) were 30.6% (8.0%), 129.5% (18.1%), and 6.7% (13.1%), respectively. QCT was performed using custom soft ware; the relationship between D(LCO) and various metrics from QCT were evaluated using Pearson correlation coefficients. On average, whole-body plethysmography volumes were higher by 841 mL compared with QCT-calculated total lung volume. However, there was a strong correlation between these measurements (r=0.824, P lung volume (r=0.314, Pvolume (r=0.498, Plung with low density (-950 Hounsfield units) (r=-0.337, Pvolume,supporting the hypothesis that pulmonary capillary blood volume is the main determinant of D(LCO) in the human lung. Th e relationships between D(LCO) and various anatomic metrics of lung parenchymal destruction from QCT inform our understanding of the relationship between structure and function of the human lung.

  2. Top-level Design and Pilot Analysis of Low-end CT Scanners Based on Linear Scanning for Developing Countries

    CERN Document Server

    Liu, Fenglin; Cong, Wenxiang; Wang, Ge

    2013-01-01

    Purpose: The goal is to develop a new architecture for computed tomography (CT) which is at an ultra-low-dose for developing countries, especially in rural areas. Methods: The proposed scheme is inspired by the recently developed compressive sensing and interior tomography techniques, where the data acquisition system targets a region of interest (ROI) to acquire limited and truncated data. The source and detector are translated in opposite directions for either ROI reconstruction with one or more localized linear scans or global reconstruction by combining multiple ROI reconstructions. In other words, the popular slip ring is replaced by a translation based setup, and the instrumentation cost is reduced by a relaxation of the imaging speed requirement. Results: The various translational scanning modes are theoretically analyzed, and the scanning parameters are optimized. The numerical simulation results from different numbers of linear scans confirm the feasibility of the proposed scheme, and suggest two pre...

  3. Autopsy case of acute multiple sclerosis with multifocal low density areas in the cerebral white matter on CT scans

    Energy Technology Data Exchange (ETDEWEB)

    Kamikura, Isao; Mizutani, Tomohiko; Sakamaki, Shuji; Takasu, Toshiaki; Kawamura, Toshiaki

    1988-01-01

    A 34-year-old woman presented with urination difficulty and consciousness disturbance, followed by persistent neurologic findings, such as semicomatose mental status and bilateral optic neuritis, and monophasic clinical course. Cranial CT showed multifocal low density areas in cerebral white matter. The patient was clinically diagnosed as having acute disseminated encephalomyelitis. She died of sepsis four months later. Autopsy revealed multifocal large demyelinating lesions confined to the cerebral white matter, shown as low density areas on CT scans, and demyelinating plaques scattered in the optic nerves and chiasm, and cerebral peduncle. The final diagnosis was acute multiple sclerosis. The CT appearance of multifocal low density areas was most likely due to demyelinating lesions causing edema and tissue necrosis. (Namekawa, K.).

  4. Estimation of absorbed doses from paediatric cone-beam CT scans: MOSFET measurements and Monte Carlo simulations.

    Science.gov (United States)

    Kim, Sangroh; Yoshizumi, Terry T; Toncheva, Greta; Frush, Donald P; Yin, Fang-Fang

    2010-03-01

    The purpose of this study was to establish a dose estimation tool with Monte Carlo (MC) simulations. A 5-y-old paediatric anthropomorphic phantom was computed tomography (CT) scanned to create a voxelised phantom and used as an input for the abdominal cone-beam CT in a BEAMnrc/EGSnrc MC system. An X-ray tube model of the Varian On-Board Imager((R)) was built in the MC system. To validate the model, the absorbed doses at each organ location for standard-dose and low-dose modes were measured in the physical phantom with MOSFET detectors; effective doses were also calculated. In the results, the MC simulations were comparable to the MOSFET measurements. This voxelised phantom approach could produce a more accurate dose estimation than the stylised phantom method. This model can be easily applied to multi-detector CT dosimetry.

  5. Effect of Scanning and Reconstruction Parameters on Three Dimensional Volume and CT Value Measurement of Pulmonary Nodules: A Phantom Study

    Directory of Open Access Journals (Sweden)

    Datong SU

    2017-08-01

    Full Text Available Background and objective The computed tomography (CT follow-up of indeterminate pulmonary nodules aiming to evaluate the change of the volume and CT value is the common strategy in clinic. The CT dose needs to considered on serious CT scans in addition to the measurement accuracy. The purpose of this study is to quantify the precision of pulmonary nodule volumetric measurement and CT value measurement with various tube currents and reconstruction algorithms in a phantom study with dual-energy CT. Methods A chest phantom containing 9 artificial spherical solid nodules with known diameter (D=2.5 mm, 5 mm, 10 mm and density (-100 HU, 60 HU and 100 HU was scanned using a 64-row detector CT canner at 120 Kilovolt & various currents (10 mA, 20 mA, 50 mA, 80 mA,100 mA, 150 mA and 350 mA. Raw data were reconstructed with filtered back projection and three levels of adaptive statistical iterative reconstruction algorithm (FBP, ASIR; 30%, 50% and 80%. Automatic volumetric measurements were performed using commercially available software. The relative volume error (RVE and the absolute attenuation error (AAE between the software measures and the reference-standard were calculated. Analyses of the variance were performed to evaluate the effect of reconstruction methods, different scan parameters, nodule size and attenuation on the RPE. Results The software substantially overestimated the very small (D=2.5 mm nodule's volume [mean RVE: (100.8%±28%] and underestimated it attenuation [mean AAE: (-756±80 HU]. The mean RVEs of nodule with diameter as 5 mm and 10 mm were small [(-0.9%±1.1% vs (0.9%±1.4%], however, the mean AAEs [(-243±26 HU vs (-129±7 HU] were large. The ANOVA analysis for repeated measurements showed that different tube current and reconstruction algorithm had no significant effect on the volumetric measurements for nodules with diameter of 5 mm and 10 mm (F=5.60, P=0.10 vs F=11.13, P=0.08, but significant effects on the measurement of CT

  6. Incidental musculoskeletal lesions detected on abdomnopelvic CT scans: A pictorial essay

    Energy Technology Data Exchange (ETDEWEB)

    Song, Eun Jee; Ryu, Kyung Nam; Park, Ji Seon [Dept. of Radiology, Kyung Hee University Hospital, Seoul (Korea, Republic of); Jin, Wook; Park, So Young [Dept. of Radiology, Kyung Hee University Hospital at Gangdong Hospital, Seoul (Korea, Republic of)

    2015-02-15

    Various musculoskeletal findings incidentally detected on abdominopelvic computed tomography (CT) images have risen with the increasing use of abdominopelvic CT; however, it is not uncommon for radiologists to overlook the musculoskeletal system when they examine abdominopelvic CT images. Some musculoskeletal lesions may have more clinical significance than abdominopelvic lesions, although most lesions are of little to no significance. Many osseous lesions can be diagnosed using the bone window setting and reconstructed images. The purpose of this article was to review the wide variety of musculoskeletal lesions depicted on abdominopelvic CT images and to emphasize the use of the bone window setting.

  7. Burden of subclinical heart and lung disease detected on thoracic CT scans of HIV patients on HAART

    Directory of Open Access Journals (Sweden)

    Stefano Zona

    2014-11-01

    Full Text Available Introduction: The aim was to determine the prevalence of lung and heart abnormalities on thoracic CT scans in HIV-infected patients who were treated with antiretroviral therapy (ART. Material and Methods: Thoracic CT scans of 903 patients infected with HIV (mean age 48±7 yrs, 29% females were reviewed by three radiologists by consensus. Patients were phenotyped according to smoking status, pack years and years since cessation for ex-smokers. Individuals known to have active lung or heart disease at the time of CT scanning were excluded. Multimorbidity lung and heart disease (MLHD was defined by the presence of >2 lung or heart abnormalities on the CT scan. Results: Prevalence of lung abnormalities were: 326 patients (36.1% with emphysema, 271 (30.0% with bronchiolitis, 44 (4.9% with non-calcified lung nodules, 568 (63% with significant bronchial wall thickening, 150 (16.7% with bronchiectasis, 9 (1% with interstitial lung disease. Overall, 445 patients (49.3% had >2 lung abnormalities. Imaging findings suggestive of prior myocardial infarction (MI were found in 1.4% (13 patients; 26.6% (240 patients had CAC scores of 1 to 100, and 9.8% (89 patients had CAC>100. 13.6% (123 patients of the patients had CAC>100 and/or previous MI. MLHD was present in 484 patients (53.6% and among 78 patients (16% who never smoked. Table 1 describes CT findings according to pack year and stop smoking groups vs never smokers.MLHD increased proportional to cumulative smoking history (p for trend <0.001 and decreased in proportion to the number of years since smoking cessation (p for trend=0.017. Independent predictors for MLHD were: age (OR=1.07, CI 1.05–1.10, sex (OR=1.59, CI 1.15–2.19, current smoking (OR=1.76, CI 1.08–2.89, and pack-years history of smoking (OR=1.03, CI 1.02–1.05. In patients who never smoked, nadir CD4<200 was significantly associated with MLHD after adjustment for age and sex (OR=1.98, CI 1.98–3.63. Conclusions: MLHD is common in HIV

  8. Automated detection and quantification of micronodules in thoracic CT scans to identify subjects at risk for silicosis

    Science.gov (United States)

    Jacobs, C.; Opdam, S. H. T. T.; van Rikxoort, E. M.; Mets, O. M.; Rooyackers, J.; de Jong, P. A.; Prokop, M.; van Ginneken, B.

    2014-03-01

    Silica dust-exposed individuals are at high risk of developing silicosis, a fatal and incurable lung disease. The presence of disseminated micronodules on thoracic CT is the radiological hallmark of silicosis but locating micronodules, to identify subjects at risk, is tedious for human observers. We present a computer-aided detection scheme to automatically find micronodules and quantify micronodule load. The system used lung segmentation, template matching, and a supervised classification scheme. The system achieved a promising sensitivity of 84% at an average of 8.4 false positive marks per scan. In an independent data set of 54 CT scans in which we defined four risk categories, the CAD system automatically classified 83% of subjects correctly, and obtained a weighted kappa of 0.76.

  9. If brain scans really detected deception, who would volunteer to be scanned?

    Science.gov (United States)

    Spence, Sean A; Hope-Urwin, Alexandra; Lankappa, Sudheer T; Woodhead, Jean; Burgess, Jenny C L; Mackay, Alice V

    2010-09-01

    Recent neuroimaging studies investigating the neural correlates of deception among healthy people, have raised the possibility that such methods may eventually be applied during legal proceedings. Were this so, who would volunteer to be scanned? We report a "natural experiment" casting some light upon this question. Following broadcast of a television series describing our team's investigative neuroimaging of deception in 2007, we received unsolicited (public) correspondence for 12 months. Using a customized template to examine this material, three independent assessors unanimously rated 30 of an initial 56 communications as unequivocally constituting requests for a "scan" (to demonstrate their author's "innocence"). Compared with the rest, these index communications were more likely to originate from incarcerated males, who were also more likely to engage in further correspondence. Hence, in conclusion, if neuroimaging were to become an acceptable means of demonstrating innocence then incarcerated males may well constitute those volunteering for such investigation. © 2010 American Academy of Forensic Sciences.

  10. CT and MRI assessment and characterization using segmentation and 3D modeling techniques: applications to muscle, bone and brain

    Directory of Open Access Journals (Sweden)

    Paolo Gargiulo

    2014-03-01

    Full Text Available This paper reviews the novel use of CT and MRI data and image processing tools to segment and reconstruct tissue images in 3D to determine characteristics of muscle, bone and brain.This to study and simulate the structural changes occurring in healthy and pathological conditions as well as in response to clinical treatments. Here we report the application of this methodology to evaluate and quantify: 1. progression of atrophy in human muscle subsequent to permanent lower motor neuron (LMN denervation, 2. muscle recovery as induced by functional electrical stimulation (FES, 3. bone quality in patients undergoing total hip replacement and 4. to model the electrical activity of the brain. Study 1: CT data and segmentation techniques were used to quantify changes in muscle density and composition by associating the Hounsfield unit values of muscle, adipose and fibrous connective tissue with different colors. This method was employed to monitor patients who have permanent muscle LMN denervation in the lower extremities under two different conditions: permanent LMN denervated not electrically stimulated and stimulated. Study 2: CT data and segmentation techniques were employed, however, in this work we assessed bone and muscle conditions in the pre-operative CT scans of patients scheduled to undergo total hip replacement. In this work, the overall anatomical structure, the bone mineral density (BMD and compactness of quadriceps muscles and proximal femoral was computed to provide a more complete view for surgeons when deciding which implant technology to use. Further, a Finite element analysis provided a map of the strains around the proximal femur socket when solicited by typical stresses caused by an implant press fitting. Study 3 describes a method to model the electrical behavior of human brain using segmented MR images. The aim of the work is to use these models to predict the electrical activity of the human brain under normal and pathological

  11. CT and MRI Assessment and Characterization Using Segmentation and 3D Modeling Techniques: Applications to Muscle, Bone and Brain.

    Science.gov (United States)

    Gargiulo, Paolo; Helgason, Thordur; Ramon, Ceon; Jr, Halldór Jónsson; Carraro, Ugo

    2014-03-31

    This paper reviews the novel use of CT and MRI data and image processing tools to segment and reconstruct tissue images in 3D to determine characteristics of muscle, bone and brain. This to study and simulate the structural changes occurring in healthy and pathological conditions as well as in response to clinical treatments. Here we report the application of this methodology to evaluate and quantify: 1. progression of atrophy in human muscle subsequent to permanent lower motor neuron (LMN) denervation, 2. muscle recovery as induced by functional electrical stimulation (FES), 3. bone quality in patients undergoing total hip replacement and 4. to model the electrical activity of the brain. Study 1: CT data and segmentation techniques were used to quantify changes in muscle density and composition by associating the Hounsfield unit values of muscle, adipose and fibrous connective tissue with different colors. This method was employed to monitor patients who have permanent muscle LMN denervation in the lower extremities under two different conditions: permanent LMN denervated not electrically stimulated and stimulated. Study 2: CT data and segmentation techniques were employed, however, in this work we assessed bone and muscle conditions in the pre-operative CT scans of patients scheduled to undergo total hip replacement. In this work, the overall anatomical structure, the bone mineral density (BMD) and compactness of quadriceps muscles and proximal femoral was computed to provide a more complete view for surgeons when deciding which implant technology to use. Further, a Finite element analysis provided a map of the strains around the proximal femur socket when solicited by typical stresses caused by an implant press fitting. Study 3 describes a method to model the electrical behavior of human brain using segmented MR images. The aim of the work is to use these models to predict the electrical activity of the human brain under normal and pathological conditions by

  12. Measurements of Epidural Space Depth Using Preexisting CT Scans Correlate with Loss of Resistance Depth during Thoracic Epidural Catheter Placement

    Directory of Open Access Journals (Sweden)

    Nathaniel H. Greene

    2015-01-01

    Full Text Available Background. Thoracic epidural catheters provide the best quality postoperative pain relief for major abdominal and thoracic surgical procedures, but placement is one of the most challenging procedures in the repertoire of an anesthesiologist. Most patients presenting for a procedure that would benefit from a thoracic epidural catheter have already had high resolution imaging that may be useful to assist placement of a catheter. Methods. This retrospective study used data from 168 patients to examine the association and predictive power of epidural-skin distance (ESD on computed tomography (CT to determine loss of resistance depth acquired during epidural placement. Additionally, the ability of anesthesiologists to measure this distance was compared to a radiologist, who specializes in spine imaging. Results. There was a strong association between CT measurement and loss of resistance depth (P35 changed this relationship (P=0.007. The ability of anesthesiologists to make CT measurements was similar to a gold standard radiologist (all individual ICCs>0.9. Conclusions. Overall, this study supports the examination of a recent CT scan to aid in the placement of a thoracic epidural catheter. Making use of these scans may lead to faster epidural placements, fewer accidental dural punctures, and better epidural blockade.

  13. Measurements of Epidural Space Depth Using Preexisting CT Scans Correlate with Loss of Resistance Depth during Thoracic Epidural Catheter Placement.

    Science.gov (United States)

    Greene, Nathaniel H; Cobb, Benjamin G; Linnau, Ken F; Kent, Christopher D

    2015-01-01

    Background. Thoracic epidural catheters provide the best quality postoperative pain relief for major abdominal and thoracic surgical procedures, but placement is one of the most challenging procedures in the repertoire of an anesthesiologist. Most patients presenting for a procedure that would benefit from a thoracic epidural catheter have already had high resolution imaging that may be useful to assist placement of a catheter. Methods. This retrospective study used data from 168 patients to examine the association and predictive power of epidural-skin distance (ESD) on computed tomography (CT) to determine loss of resistance depth acquired during epidural placement. Additionally, the ability of anesthesiologists to measure this distance was compared to a radiologist, who specializes in spine imaging. Results. There was a strong association between CT measurement and loss of resistance depth (P 35) changed this relationship (P = 0.007). The ability of anesthesiologists to make CT measurements was similar to a gold standard radiologist (all individual ICCs > 0.9). Conclusions. Overall, this study supports the examination of a recent CT scan to aid in the placement of a thoracic epidural catheter. Making use of these scans may lead to faster epidural placements, fewer accidental dural punctures, and better epidural blockade.

  14. Do bonding agents protect the bracket-periphery?--Evaluation by consecutive μCT scans and fluorescence measurements.

    Science.gov (United States)

    Paschos, Ekaterini; Galosi, Teresa; Huth, Karin C; Rudzki, Ingrid; Wichelhaus, Andrea; Kunzelmann, Karl-Heinz

    2015-01-01

    The aim of this in vitro study was to consecutively determine the effect of three bonding agents on the prevention of enamel demineralisation at the bracket-periphery and to compare the suitability of micro-computed tomography (μCT) scans and quantitative light-induced fluorescence (QLF) to detect changes within subsurface lesions. The effect of a resin-modified glass ionomer cement (RMGI) (Fuji Ortho LC), a compomer (Assure) and a composite (Transbond XT) on the prevention of enamel demineralisation at the bracket-periphery was examined. After 7, 14, 21 and 28 days of pH cycling, the teeth (N = 45) were examined by consecutive μCT scans and by using a customised QLF set-up. Particularly for the RMGI and for the compomer, the QLF and μCT scans showed that the formation and the body of the lesion were not precisely located at the enamel next to the bracket margin. There was an area that was almost protected. The progression of demineralisation was decreased for the RMGI and the compomer-treated teeth. For bonding orthodontic brackets, the RMGI and compomer were comparably able to decrease the progression of white spot lesions (WSL), although the RMGI showed marginally superior protection. Both methods (QLF and μCT scans) were suitable for investigating the longitudinal fluoride effects on WSL, though these effects were more accurately described by mineral (fluorescence) loss or volume changes than by lesion depth. The progression of WSL at the bracket-periphery could be altered by using fluoride-releasing bonding agents for bracket application. This approach represents a minimally invasive preventive measure.

  15. CT brain demonstration of basal ganglion calcification in adult HIV ...

    African Journals Online (AJOL)

    brain barrier has been postulated. Calcification of the basal ganglia in encephalopathic HIV/AIDS children has been relatively well documented. Only two adult HIV cases with basal ganglion calcification (BGC) have been reported in the literature.

  16. (18)F-Choline PET/CT scan in staging and biochemical recurrence in prostate cancer patients: Changes in classification and radiotherapy planning.

    Science.gov (United States)

    Cardona Arboniés, J; Rodríguez Alfonso, B; Mucientes Rasilla, J; Martínez Ballesteros, C; Zapata Paz, I; Prieto Soriano, A; Carballido Rodriguez, J; Mitjavila Casanovas, M

    To evaluate the role of the (18)F-Choline PET/CT in prostate cancer management when detecting distant disease in planning radiotherapy and staging and to evaluate the therapy changes guided by PET/TC results. A retrospective evaluation was performed on (18)F-Choline PET/CT scans of patients with prostate cancer. Staging and planning radiotherapy scans were selected in patients with at least 9 months follow up. There was a total of 56 studies, 33 (58.93%) for staging, and 23 (41.07%) for planning radiotherapy. All scans were obtained using a hybrid PET/CT scanner. The PET/CT acquisition protocol consisted of a dual-phase procedure after the administration of an intravenous injection of 296-370MBq of (18)F-Choline. There were 43 out of 56 (76.8%) scans considered as positive, and 13 (23.2%) were negative. The TNM staging was changed in 13 (23.2%) scans. The PET/CT findings ruled out distant disease in 4 out of 13 scans, and unknown distant disease was detected in 9 (69.3%) scans. (18)F-Choline PET/CT is a useful technique for detecting unknown distant disease in prostate cancer when staging and planning radiotherapy. The inclusion of (18)F-choline PET/CT should be considered in prostate cancer management protocols. Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

  17. Automated method to compute Evans index for diagnosis of idiopathic normal pressure hydrocephalus on brain CT images

    Science.gov (United States)

    Takahashi, Noriyuki; Kinoshita, Toshibumi; Ohmura, Tomomi; Matsuyama, Eri; Toyoshima, Hideto

    2017-03-01

    The early diagnosis of idiopathic normal pressure hydrocephalus (iNPH) considered as a treatable dementia is important. The iNPH causes enlargement of lateral ventricles (LVs). The degree of the enlargement of the LVs on CT or MR images is evaluated by using a diagnostic imaging criterion, Evans index. Evans index is defined as the ratio of the maximal width of frontal horns (FH) of the LVs to the maximal width of the inner skull (IS). Evans index is the most commonly used parameter for the evaluation of ventricular enlargement. However, manual measurement of Evans index is a time-consuming process. In this study, we present an automated method to compute Evans index on brain CT images. The algorithm of the method consisted of five major steps: standardization of CT data to an atlas, extraction of FH and IS regions, the search for the outmost points of bilateral FH regions, determination of the maximal widths of both the FH and the IS, and calculation of Evans index. The standardization to the atlas was performed by using linear affine transformation and non-linear wrapping techniques. The FH regions were segmented by using a three dimensional region growing technique. This scheme was applied to CT scans from 44 subjects, including 13 iNPH patients. The average difference in Evans index between the proposed method and manual measurement was 0.01 (1.6%), and the correlation coefficient of these data for the Evans index was 0.98. Therefore, this computerized method may have the potential to accurately compute Evans index for the diagnosis of iNPH on CT images.

  18. Adenosine-stress low-dose single-scan CT myocardial perfusion imaging using a 128-slice dual-source CT: a comparison with fractional flow reserve.

    Science.gov (United States)

    Choo, Ki Seok; Hwangbo, Lee; Kim, June Hong; Park, Yong Hyun; Kim, Jeong Su; Kim, Jun; Chun, Kook Jin; Jeong, Dong Wook; Lim, Soo Jin

    2013-05-01

    Coronary CT angiography (CCTA) allows accurate evaluation of coronary artery stenosis but has limitations in information on hemodynamic significance of stenotic lesions. To determine the feasibility of adenosine-stress low-dose single-scan CT myocardial perfusion imaging (MPI) using a 128-slice dual-source CT scanner for the diagnosis of hemodynamically significant coronary artery stenosis as defined by fractional flow reserve (FFR). This study was proved by the Institutional Review Board and informed consent was obtained from the patients before enrollment in the study. Ninety-seven patients with chest pain and low-to-intermediate pretest probability of coronary artery disease were prospectively enrolled. Adenosine-stress CCTA using ECG-correlated maximum tube current modulation (Mindose(®)) with 128-slice dual-source CT was performed in all 97 patients. In 37 patients (38.1%; 28 men, nine women; mean age, 61.7 ± 20.5 years; mean heart rate, 74.6 ± 2.8 bpm) with significant stenosis at CCTA (lumen diameter reduction >50%), FFR was performed after CCTA, as a reference standard for the evaluation of myocardial perfusion. FFR value ≤0.75 was considered as positive. CTMPI and CCTA were read by two experienced radiologists with consensus, respectively. The effective radiation dose of adenosine-stress single-scan CTMPI was 4.63 ± 2.57 mSv. Compared with FFR, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for identifying significant coronary stenoses were 93.1%, 82.7%, 75.0%, and 95.6%, respectively, on CCTA and 93.1%, 90.3%, 84.4%, and 95.9%, respectively, on CTMPI. On combined CCTA and CTMPI, sensitivity, specificity, PPV, and NPV were 93.1%, 94.2%, 90.0%, and 96.0%, respectively. Adenosine-stress low-dose single scan CTMPI using a 128-slice dual-source CT can provide complementary information on the hemodynamical significance of coronary artery stenosis as well as anatomical information of coronary arteries.

  19. Evaluation of bismuth shielding effectiveness in reducing breast absorbed dose during thoracic CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, T. C.; Mourao, A. P.; Santana, P. C.; Silva, T. A. [Federal University of Minas Gerais, Program of Nuclear Science and Techniques, Av. Pte. Antonio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais (Brazil)

    2015-10-15

    Computed Tomography (CT) is an essential method for tracking neoplasia and efficiently diagnosing a wide variety of thoracic diseases. CT is generally considered the most accurate choice for lung examination. Due to the growing use of CT, breast and other superficial and radiosensitive organs are unnecessarily irradiated during radiological procedures, thus requiring the development of strategies appropriate to optimize and, if possible, to reduce the radiation dose. The use of bismuth shielding to reduce radiation dose absorbed by breast during thoracic CT examinations has been the subject of many studies recently published by Brazilian and foreign authors of various fields. The purpose of this paper is both to accurately determine the glandular dose when breast is exposed to radiation and to assess the reduction in absorbed dose during thoracic CT examinations, using a set of Thermoluminescent Dosimeters, an anthropomorphic phantom and bismuth shielding. (Author)

  20. Predicting need for additional CT scan in children with a non-diagnostic ultrasound for appendicitis in the emergency department.

    Science.gov (United States)

    Nishizawa, Takuya; Maeda, Shigenobu; Goldman, Ran D; Hayashi, Hiroyuki

    2018-01-01

    This study aimed to determine which children with suspected appendicitis should be considered for a computerized tomography (CT) scan after a non-diagnostic ultrasound (US) in the Emergency Department (ED). We retrospectively reviewed patients 0-18year old, who presented to the ED with complaints of abdominal pain, during 2011-2015 and while in the hospital had both US and CT. We recorded demographic and clinical data and outcomes, and used univariate and multivariate methods for comparing patients who did and didn't have appendicitis on CT after non-diagnostic US. Multivariate analysis was performed using logistic regression to determine what variables were independently associated with appendicitis. A total of 328 patients were enrolled, 257 with non-diagnostic US (CT: 82 had appendicitis, 175 no-appendicitis). Younger children and those who reported vomiting or had right lower abdominal quadrant (RLQ) tenderness, peritoneal signs or White Blood Cell (WBC) count >10,000 in mm 3 were more likely to have appendicitis on CT. RLQ tenderness (Odds Ratio: 2.84, 95%CI: 1.07-7.53), peritoneal signs (Odds Ratio: 11.37, 95%CI: 5.08-25.47) and WBC count >10,000 in mm 3 (Odds Ratio: 21.88, 95%CI: 7.95-60.21) remained significant after multivariate analysis. Considering CT with 2 or 3 of these predictors would have resulted in sensitivity of 94%, specificity of 67%, positive predictive value of 57% and negative predictive value of 96% for appendicitis. Ordering CT should be considered after non-diagnostic US for appendicitis only when children meet at least 2 predictors of RLQ tenderness, peritoneal signs and WBC>10,000 in mm 3 . Copyright © 2017 Elsevier Inc. All rights reserved.

  1. A correlative optical microscopy and scanning electron microscopy approach to locating nanoparticles in brain tumors.

    Science.gov (United States)

    Kempen, Paul J; Kircher, Moritz F; de la Zerda, Adam; Zavaleta, Cristina L; Jokerst, Jesse V; Mellinghoff, Ingo K; Gambhir, Sanjiv S; Sinclair, Robert

    2015-01-01

    The growing use of nanoparticles in biomedical applications, including cancer diagnosis and treatment, demands the capability to exactly locate them within complex biological systems. In this work a correlative optical and scanning electron microscopy technique was developed to locate and observe multi-modal gold core nanoparticle accumulation in brain tumor models. Entire brain sections from mice containing orthotopic brain tumors injected intravenously with nanoparticles were imaged using both optical microscopy to identify the brain tumor, and scanning electron microscopy to identify the individual nanoparticles. Gold-based nanoparticles were readily identified in the scanning electron microscope using backscattered electron imaging as bright spots against a darker background. This information was then correlated to determine the exact location of the nanoparticles within the brain tissue. The nanoparticles were located only in areas that contained tumor cells, and not in the surrounding healthy brain tissue. This correlative technique provides a powerful method to relate the macro- and micro-scale features visible in light microscopy with the nanoscale features resolvable in scanning electron microscopy. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Establishing a process of irradiating small animal brain using a CyberKnife and a microCT scanner

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Haksoo; Welford, Scott [Department of Radiation Oncology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106 (United States); Fabien, Jeffrey; Zheng, Yiran; Yuan, Jake; Brindle, James; Yao, Min; Lo, Simon; Wessels, Barry; Machtay, Mitchell; Sohn, Jason W., E-mail: jason.sohn@case.edu [Department of Radiation Oncology, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106 and University Hospitals of Cleveland, 11100 Euclid Avenue, Cleveland, Ohio 44106 (United States); Sloan, Andrew [Department of Neurosurgery, School of Medicine, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106 (United States)

    2014-02-15

    Purpose: Establish and validate a process of accurately irradiating small animals using the CyberKnife G4 System (version 8.5) with treatment plans designed to irradiate a hemisphere of a mouse brain based on microCT scanner images. Methods: These experiments consisted of four parts: (1) building a mouse phantom for intensity modulated radiotherapy (IMRT) quality assurance (QA), (2) proving usability of a microCT for treatment planning, (3) fabricating a small animal positioning system for use with the CyberKnife's image guided radiotherapy (IGRT) system, and (4)in vivo verification of targeting accuracy. A set of solid water mouse phantoms was designed and fabricated, with radiochromic films (RCF) positioned in selected planes to measure delivered doses. After down-sampling for treatment planning compatibility, a CT image set of a phantom was imported into the CyberKnife treatment planning system—MultiPlan (ver. 3.5.2). A 0.5 cm diameter sphere was contoured within the phantom to represent a hemispherical section of a mouse brain. A nude mouse was scanned in an alpha cradle using a microCT scanner (cone-beam, 157 × 149 pixels slices, 0.2 mm longitudinal slice thickness). Based on the results of our positional accuracy study, a planning treatment volume (PTV) was created. A stereotactic body mold of the mouse was “printed” using a 3D printer laying UV curable acrylic plastic. Printer instructions were based on exported contours of the mouse's skin. Positional reproducibility in the mold was checked by measuring ten CT scans. To verify accurate dose delivery in vivo, six mice were irradiated in the mold with a 4 mm target contour and a 2 mm PTV margin to 3 Gy and sacrificed within 20 min to avoid DNA repair. The brain was sliced and stained for analysis. Results: For the IMRT QA using a set of phantoms, the planned dose (6 Gy to the calculation point) was compared to the delivered dose measured via film and analyzed using Gamma analysis (3% and 3 mm

  3. Brain tumor delineation based on CT and MR imaging. Implications for radiotherapy treatment planning

    NARCIS (Netherlands)

    Heesters, M A; Wijrdeman, H K; Struikmans, H; Witkamp, T; Moerland, M A

    1993-01-01

    This paper deals with the impact MRI may have on radiotherapy treatment planning of brain tumors. The authors analyzed differences in size and position of treatment fields as indicated by three observers (two radiotherapists and one neuroradiologist) using CT or MR based radiotherapy planning

  4. The usefulness of brain MRI and CT in the clinical practice of epilepsia

    Energy Technology Data Exchange (ETDEWEB)

    Horita, Hideki [Jikei Univ., Komae, Tokyo (Japan). Daisan Hospital; Maekawa, Kihei

    1995-09-01

    This study was conducted to clarify the usefulness of brain MRI and CT in the clinical practice of epilepsy. The subjects were 100 epileptic child patients (average age, 13.2{+-}8.2 years) who underwent brain MRI, including 93 patients who also underwent brain CT. Twenty-two abnormal findings were obtained by MRI and 25 by CT. Thirty-nine patients who had complications such as mental retardation, cerebral palsy, or the overlapping disorders showed abnormal findings in a significantly high incidence. No significant correlations existed between the presence or absence of abnormal findings and the disease course after seizures. Patients with symptomatic localization-related epilepsies or cryptogenic and symptomatic generalized epilepsies showed abnormal findings in a significantly high incidence and unfavorable disease course after seizures. In 10 of 28 patients who showed abnormal findings, the abnormal finding site on images were correlated to the focus site on electroencephalograms. In conclusion, brain MRI and CT are essential in the clinical practice of epilepsy, however, we should notice the limitation of these methods. (Y.S.).

  5. Role of18F-FDG PET/CT in primary brain lymphoma.

    Science.gov (United States)

    de-Bonilla-Damiá, Á; Fernández-López, R; Capote-Huelva, F J; de la Cruz-Vicente, F; Egea-Guerrero, J J; Borrego-Dorado, I

    To study the usefulness of 18 F-FDG PET/CT in the initial evaluation and in the response assessment in primary brain lymphoma. A retrospective analysis was carried out on 18 patients diagnosed with primary brain lymphoma, a histological subtype of diffuse large B-cell lymphoma, on whom an initial 18 F-FDG PET/CT and MRI was performed, with 7 of the cases being analysed after the completion of treatment in order to assess response and clinical follow up. Initial 18 F-FDG PET/CT showed 26 hypermetabolic foci, whereas 46 lesions were detected by MRI. The average SUV maximum of the lesions was 17.56 with T/N 3.55. The concordance of both tests for identifying the same number of lesions was moderate, obtaining a kappa index of 0.395 (P<.001). In the evaluation of treatment, MRI identified 16 lesions compared to 7 pathological accumulations observed by 18 F-FDG PET/CT. The concordance of both tests to assess type of response to treatment was moderate (kappa index 0.41) (P=.04). In both the initial evaluation and the assessment of the response to treatment, PET/CT led to a change strategy in 22% of patients who had lesions outside the cerebral parenchyma. MRI appears to be the method of choice for detecting brain disease in patients with primary brain lymphoma, whereas 18 F-FDG PET/CT seems to play a relevant role in the assessment of extra-cerebral disease. Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

  6. Breast dose reduction for chest CT by modifying the scanning parameters based on the pre-scan size-specific dose estimate (SSDE)

    Energy Technology Data Exchange (ETDEWEB)

    Kidoh, Masafumi; Utsunomiya, Daisuke; Oda, Seitaro; Nakaura, Takeshi; Yuki, Hideaki; Hirata, Kenichiro; Namimoto, Tomohiro; Sakabe, Daisuke; Hatemura, Masahiro; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Faculty of Life Sciences, Honjo, Kumamoto (Japan); Funama, Yoshinori [Kumamoto University, Department of Medical Physics, Faculty of Life Sciences, Honjo, Kumamoto (Japan)

    2017-06-15

    To investigate the usefulness of modifying scanning parameters based on the size-specific dose estimate (SSDE) for a breast-dose reduction for chest CT. We scanned 26 women with a fixed volume CT dose index (CTDI{sub vol}) (15 mGy) and another 26 with a fixed SSDE (15 mGy) protocol (protocol 1 and 2, respectively). In protocol 2, tube current was calculated based on the patient habitus obtained on scout images. We compared the mean breast dose and the inter-patient breast dose variability and performed linear regression analysis of the breast dose and the body mass index (BMI) of the two protocols. The mean breast dose was about 35 % lower under protocol 2 than protocol 1 (10.9 mGy vs. 16.8 mGy, p < 0.01). The inter-patient breast dose variability was significantly lower under protocol 2 than 1 (1.2 mGy vs. 2.5 mGy, p < 0.01). We observed a moderate negative correlation between the breast dose and the BMI under protocol 1 (r = 0.43, p < 0.01); there was no significant correlation (r = 0.06, p = 0.35) under protocol 2. The SSDE-based protocol achieved a reduction in breast dose and in inter-patient breast dose variability. (orig.)

  7. CT Scans in Young People in Great Britain: Temporal and Descriptive Patterns, 1993–2002

    Directory of Open Access Journals (Sweden)

    Mark S. Pearce

    2012-01-01

    Results. The number of CT examinations doubled over the study period. While increases in numbers of recorded examinations were seen across all age groups, the greatest increases were in the older patients, most notably those aged 15–19 years of age. Sixty percent of CT examinations were of the head, with the percentages varying with calendar year and patient age. Conclusions. In contrast to previous data from the North of England, the doubling of CT use was not accompanied by an increase in numbers of multiple examinations to the same individual.

  8. CT head-scan dosimetry in an anthropomorphic phantom and associated measurement of ACR accreditation-phantom imaging metrics under clinically representative scan conditions

    Energy Technology Data Exchange (ETDEWEB)

    Brunner, Claudia C.; Stern, Stanley H.; Chakrabarti, Kish [U.S. Food and Drug Administration, 10903 New Hampshire Avenue, Silver Spring, Maryland 20993 (United States); Minniti, Ronaldo [National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, Maryland 20899 (United States); Parry, Marie I. [Walter Reed National Military Medical Center, 8901 Rockville Pike, Bethesda, Maryland 20889 (United States); Skopec, Marlene [National Institutes of Health, 9000 Rockville Pike, Bethesda, Maryland 20892 (United States)

    2013-08-15

    Purpose: To measure radiation absorbed dose and its distribution in an anthropomorphic head phantom under clinically representative scan conditions in three widely used computed tomography (CT) scanners, and to relate those dose values to metrics such as high-contrast resolution, noise, and contrast-to-noise ratio (CNR) in the American College of Radiology CT accreditation phantom.Methods: By inserting optically stimulated luminescence dosimeters (OSLDs) in the head of an anthropomorphic phantom specially developed for CT dosimetry (University of Florida, Gainesville), we measured dose with three commonly used scanners (GE Discovery CT750 HD, Siemens Definition, Philips Brilliance 64) at two different clinical sites (Walter Reed National Military Medical Center, National Institutes of Health). The scanners were set to operate with the same data-acquisition and image-reconstruction protocols as used clinically for typical head scans, respective of the practices of each facility for each scanner. We also analyzed images of the ACR CT accreditation phantom with the corresponding protocols. While the Siemens Definition and the Philips Brilliance protocols utilized only conventional, filtered back-projection (FBP) image-reconstruction methods, the GE Discovery also employed its particular version of an adaptive statistical iterative reconstruction (ASIR) algorithm that can be blended in desired proportions with the FBP algorithm. We did an objective image-metrics analysis evaluating the modulation transfer function (MTF), noise power spectrum (NPS), and CNR for images reconstructed with FBP. For images reconstructed with ASIR, we only analyzed the CNR, since MTF and NPS results are expected to depend on the object for iterative reconstruction algorithms.Results: The OSLD measurements showed that the Siemens Definition and the Philips Brilliance scanners (located at two different clinical facilities) yield average absorbed doses in tissue of 42.6 and 43.1 m

  9. Clinical evaluation of a dose monitoring software tool based on Monte Carlo Simulation in assessment of eye lens doses for cranial CT scans

    Energy Technology Data Exchange (ETDEWEB)

    Guberina, Nika; Suntharalingam, Saravanabavaan; Nassenstein, Kai; Forsting, Michael; Theysohn, Jens; Wetter, Axel; Ringelstein, Adrian [University Hospital Essen, Institute of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany)

    2016-10-15

    The aim of this study was to verify the results of a dose monitoring software tool based on Monte Carlo Simulation (MCS) in assessment of eye lens doses for cranial CT scans. In cooperation with the Federal Office for Radiation Protection (Neuherberg, Germany), phantom measurements were performed with thermoluminescence dosimeters (TLD LiF:Mg,Ti) using cranial CT protocols: (I) CT angiography; (II) unenhanced, cranial CT scans with gantry angulation at a single and (III) without gantry angulation at a dual source CT scanner. Eye lens doses calculated by the dose monitoring tool based on MCS and assessed with TLDs were compared. Eye lens doses are summarized as follows: (I) CT angiography (a) MCS 7 mSv, (b) TLD 5 mSv; (II) unenhanced, cranial CT scan with gantry angulation, (c) MCS 45 mSv, (d) TLD 5 mSv; (III) unenhanced, cranial CT scan without gantry angulation (e) MCS 38 mSv, (f) TLD 35 mSv. Intermodality comparison shows an inaccurate calculation of eye lens doses in unenhanced cranial CT protocols at the single source CT scanner due to the disregard of gantry angulation. On the contrary, the dose monitoring tool showed an accurate calculation of eye lens doses at the dual source CT scanner without gantry angulation and for CT angiography examinations. The dose monitoring software tool based on MCS gave accurate estimates of eye lens doses in cranial CT protocols. However, knowledge of protocol and software specific influences is crucial for correct assessment of eye lens doses in routine clinical use. (orig.)

  10. Clinical evaluation of a dose monitoring software tool based on Monte Carlo Simulation in assessment of eye lens doses for cranial CT scans.

    Science.gov (United States)

    Guberina, Nika; Suntharalingam, Saravanabavaan; Naßenstein, Kai; Forsting, Michael; Theysohn, Jens; Wetter, Axel; Ringelstein, Adrian

    2016-10-01

    The aim of this study was to verify the results of a dose monitoring software tool based on Monte Carlo Simulation (MCS) in assessment of eye lens doses for cranial CT scans. In cooperation with the Federal Office for Radiation Protection (Neuherberg, Germany), phantom measurements were performed with thermoluminescence dosimeters (TLD LiF:Mg,Ti) using cranial CT protocols: (I) CT angiography; (II) unenhanced, cranial CT scans with gantry angulation at a single and (III) without gantry angulation at a dual source CT scanner. Eye lens doses calculated by the dose monitoring tool based on MCS and assessed with TLDs were compared. Eye lens doses are summarized as follows: (I) CT angiography (a) MCS 7 mSv, (b) TLD 5 mSv; (II) unenhanced, cranial CT scan with gantry angulation, (c) MCS 45 mSv, (d) TLD 5 mSv; (III) unenhanced, cranial CT scan without gantry angulation (e) MCS 38 mSv, (f) TLD 35 mSv. Intermodality comparison shows an inaccurate calculation of eye lens doses in unenhanced cranial CT protocols at the single source CT scanner due to the disregard of gantry angulation. On the contrary, the dose monitoring tool showed an accurate calculation of eye lens doses at the dual source CT scanner without gantry angulation and for CT angiography examinations. The dose monitoring software tool based on MCS gave accurate estimates of eye lens doses in cranial CT protocols. However, knowledge of protocol and software specific influences is crucial for correct assessment of eye lens doses in routine clinical use.

  11. SU-E-CAMPUS-J-06: The Impact of CT-Scan Energy On Range Uncertainty in Proton Therapy Planning

    Energy Technology Data Exchange (ETDEWEB)

    Grantham, K [University of Missouri-Columbia, St. Louis, MO (United States); Li, H [Washington University School of Medicine, Saint Louis, MO (United States); Zhao, T [Washington University School of Medicine, St. Louis, MO (United States); Klein, E [Washington University, Saint Louis, MO (United States)

    2014-06-15

    Purpose: To investigate the impact of tube potential (kVp) on the CTnumber (HU) to proton stopping power ratio (PSPR) conversion table; the range uncertainty and the dosimetric change introduced by a mismatch in kVp between the CT and the HU to PSPR table used to calculate dose are analyzed. Methods: A CIRS CT-ED phantom was scanned with a Philips Brilliance 64-slice scanner under 90kVp and 120kVp tube potentials. Two HU to PSPR curves were then created. Using Eclipse (Varian) a treatment plan was created for a single beam in a water phantom (HU=0) passing through a wedge-shaped heterogeneity (HU=1488). The dose was recalculated by changing only the HU to PSPR table used in the dose calculation. The change in range (the distal 90% isodose line) relative to a distal structure was recorded as a function of heterogeneity thickness in the beam. To show the dosimetric impact of a mismatch in kVp between the CT and the HU to PSPR table, we repeated this procedure using a clinical plan comparing DVH data. Results: The HU to PSPR tables diverge for low-density bone and higher density structures. In the phantom plan, the divergence of the tables results in a change in range of ~1mm per cm of bone in the beam path for the HU used. For the clinical plan, a mismatch in kVp showed a 28% increase in mean dose to the brainstem along with a 10% increase in maximum dose to the brainstem center. Conclusion: A mismatch in kVp between the CT and the HU to PSPR table can introduce significant uncertainty in the proton beam range. For dense bone, the measured range uncertainty is about 1mm per cm of bone in the beam. CT-scan energy verification should be employed, particularly when high-density media is in the proton beam path.

  12. Model-based x-ray energy spectrum estimation algorithm from CT scanning data with spectrum filter

    Science.gov (United States)

    Li, Lei; Wang, Lin-Yuan; Yan, Bin

    2016-10-01

    With the development of technology, the traditional X-ray CT can't meet the modern medical and industry needs for component distinguish and identification. This is due to the inconsistency of X-ray imaging system and reconstruction algorithm. In the current CT systems, X-ray spectrum produced by X-ray source is continuous in energy range determined by tube voltage and energy filter, and the attenuation coefficient of object is varied with the X-ray energy. So the distribution of X-ray energy spectrum plays an important role for beam-hardening correction, dual energy CT image reconstruction or dose calculation. However, due to high ill-condition and ill-posed feature of system equations of transmission measurement data, statistical fluctuations of X ray quantum and noise pollution, it is very hard to get stable and accurate spectrum estimation using existing methods. In this paper, a model-based X-ray energy spectrum estimation method from CT scanning data with energy spectrum filter is proposed. First, transmission measurement data were accurately acquired by CT scan and measurement using phantoms with different energy spectrum filter. Second, a physical meaningful X-ray tube spectrum model was established with weighted gaussian functions and priori information such as continuity of bremsstrahlung and specificity of characteristic emission and estimation information of average attenuation coefficient. The parameter in model was optimized to get the best estimation result for filtered spectrum. Finally, the original energy spectrum was reconstructed from filtered spectrum estimation with filter priori information. Experimental results demonstrate that the stability and accuracy of X ray energy spectrum estimation using the proposed method are improved significantly.

  13. Radiation dose reduction at a price: the effectiveness of a male gonadal shield during helical CT scans

    Directory of Open Access Journals (Sweden)

    Erdi Yusuf E

    2007-03-01

    Full Text Available Abstract Background It is estimated that 60 million computed tomography (CT scans were performed during 2006, with approximately 11% of those performed on children age 0–15 years. Various types of gonadal shielding have been evaluated for reducing exposure to the gonads. The purpose of this study was to quantify the radiation dose reduction to the gonads and its effect on image quality when a wrap-around male pediatric gonad shield was used during CT scanning. This information is obtained to assist the attending radiologist in the decision to utilize such male gonadal shields in pediatric imaging practice. Methods The dose reduction to the gonads was measured for both direct radiation and for indirect scattered radiation from the abdomen. A 6 cm3 ion chamber (Model 10X5-6, Radcal Corporation, Monrovia, CA was placed on a Humanoid real bone pelvic phantom at a position of the male gonads. When exposure measurements with shielding were made, a 1 mm lead wrap-around gonadal shield was placed around the ion chamber sensitive volume. Results The use of the shields reduced scatter dose to the gonads by a factor of about 2 with no appreciable loss of image quality. The shields reduced the direct beam dose by a factor of about 35 at the expense of extremely poor CT image quality due to severe streak artifacts. Conclusion Images in the direct exposure case are not useful due to these severe artifacts and the difficulties in positioning these shields on patients in the scatter exposure case may not be warranted by the small absolute reduction in scatter dose unless it is expected that the patient will be subjected to numerous future CT scans.

  14. Evaluation of Distal Femoral Rotational Alignment with Spiral CT Scan before Total Knee Arthroplasty (A Study in Iranian Population

    Directory of Open Access Journals (Sweden)

    Mahmoud Jabalameli

    2016-04-01

    Full Text Available Background: Evaluating the landmarks for rotation of the distal femur is a challenge for orthopedic surgeons. Although the posterior femoral condyle axis is a good landmark for surgeons, the surgical transepicondylar axis may be a better option with the help of preoperative CT scanning. The purpose of this study was to ascertain relationships among the axes’ guiding distal femur rotational alignment in preoperative CT scans of Iranian patients who were candidates for total knee arthroplasty and the effects of age, gender, and knee alignment on these relationships. Methods: One hundred and eight cases who were admitted to two university hospitals for total knee arthroplasty were included in this study. The rotation of the distal femur was evaluated using single axial CT images through the femoral epicondyle. Four lines were drawn digitally in this view: anatomical and surgical transepicondylar axes, posterior condylar axis and the Whiteside anteroposterior line. The alignment of the extremity was evaluated in the standing alignment view. Then the angles were measured along these lines and their relationship was evaluated. Results: The mean angle between the anatomical transepicondylar axis and posterior condylar axis and between the surgical transepicondylar axis and posterior condylar axis were 5.9 ± 1.6 degrees and 1.6±1.7 degrees respectively. The mean angle between the Whiteside’s anteroposterior line and the line perpendicular to the posterior condylar axis was 3.7±2.1 degrees. Significant differences existed between the two genders in these relationships. No significant correlation between the age of patients and angles of the distal femur was detected. The anatomical surgical transepicondylar axis was in 4.3 degrees external rotation in relation to the surgical transepicondylar axis. Conclusion: Preoperative CT scanning can help accurately determine rotational landmarks of the distal femur. If one of the reference axes cannot be

  15. ORIGINAL ARTICLE ORIG ORIG Ct brain demonstration of basal ...

    African Journals Online (AJOL)

    Involvement of the basal ganglia in AIDS encephalopathy is well docu- mented in both adults and children. The pathology remains obscure. A type of inflammation with increased vascularity and disruption of the blood-brain barrier has been postulated. Calcification of the basal ganglia in encephalopathic HIV/AIDS children ...

  16. 18F-DOPA PET/CT and 68Ga-DOTANOC PET/CT scans as diagnostic tools in focal congenital hyperinsulinism

    DEFF Research Database (Denmark)

    Christiansen, Charlotte Dahl; Petersen, Henrik; Nielsen, Anne Lerberg

    2017-01-01

    (68Ga-DOTANOC) PET/CT as diagnostic tools in focal CHI. Methods: PET/CT scans of children with CHI admitted to Odense University Hospital between August 2005 and June 2016 were retrospectively evaluated visually and by their maximal standardized uptake values (SUVmax) by two independent examiners...... in 34 patients, no surgery in 21 patients. Fifty-one patients had a classifiable outcome, either by histology (n = 33, 22 focal lesions, 11 non-focal) or by genetics (n = 18, all non-focal). The predictive performance of 18F-DOPA PET/CT to identify focal CHI was identical by visual- and cut......-off-based evaluation: sensitivity (95% CI) of 1 (0.85–1); specificity of 0.96 (0.82–0.99). The optimal 18F-DOPA PET SUVmax ratio cut-off was 1.44 and the optimal 68Ga-DOTANOC PET SUVmax cut-off was 6.77 g/ml. The area under the receiver operating curve was 0.98 (0.93–1) for 18F-DOPA PET vs. 0.71 (0.43–0.95) for 68Ga...

  17. Mapping metals in Parkinson's and normal brain using rapid-scanning x-ray fluorescence

    Science.gov (United States)

    Popescu, Bogdan F. Gh; George, Martin J.; Bergmann, Uwe; Garachtchenko, Alex V.; Kelly, Michael E.; McCrea, Richard P. E.; Lüning, Katharina; Devon, Richard M.; George, Graham N.; Hanson, Akela D.; Harder, Sheri M.; Chapman, L. Dean; Pickering, Ingrid J.; Nichol, Helen

    2009-02-01

    Rapid-scanning x-ray fluorescence (RS-XRF) is a synchrotron technology that maps multiple metals in tissues by employing unique hardware and software to increase scanning speed. RS-XRF was validated by mapping and quantifying iron, zinc and copper in brain slices from Parkinson's disease (PD) and unaffected subjects. Regions and structures in the brain were readily identified by their metal complement and each metal had a unique distribution. Many zinc-rich brain regions were low in iron and vice versa. The location and amount of iron in brain regions known to be affected in PD agreed with analyses using other methods. Sample preparation is simple and standard formalin-fixed autopsy slices are suitable. RS-XRF can simultaneously and non-destructively map and quantify multiple metals and holds great promise to reveal metal pathologies associated with PD and other neurodegenerative diseases as well as diseases of metal metabolism.

  18. Application of low dose radiation and low concentration contrast media in enhanced CT scans in children with congenital heart disease.

    Science.gov (United States)

    Liu, Zhimin; Song, Lei; Yu, Tong; Gao, Jun; Zhang, Qifeng; Jiang, Ling; Liu, Yong; Peng, Yun

    2016-09-01

    The aim of this study was to explore the feasibility of using low dose radiation and low concentration contrast media in enhanced CT examinations in children with congenital heart disease. Ninety patients with congenital heart disease were randomly divided into three groups of 30 patients each who underwent contrast-enhanced cardiac scans on a Discovery CT750 HD scanner. Group A received 270 mg I/mL iodixanol, and group B received 320 mg I/mL iodixanol contrast media and was scanned with prospective ECG triggering mode. Group C received 320 mg I/mL iodixanol and was scanned with conventional retrospective ECG gating mode. The same weight-based contrast injection protocol was used for all three groups. Images were reconstructed using a 30% adaptive statistical iterative reconstruction (ASIR) algorithm and a 50% ASIR in groups A and B and a 30% ASIR in group C. The subjective and objective image quality evaluations, diagnostic accuracies, radiation doses and amounts of contrast media in the three groups were measured and compared. All images in the three groups met the diagnostic requirements, with the same diagnostic accuracy and image quality scores greater than 3 in a 4-point scoring system. However, ventricular enhancement and the objective noise, signal-to-noise ratio, contrast-to-noise ratio and subjective image quality scores in group C were better than those in groups A and B (all Pcontrast dose (14% lower than that of groups B and C). Enhanced CT scan images with low dose radiation and low concentration contrast media can meet the diagnostic requirements for examining children with congenital heart disease while reducing the potential risk of radiation damage and contrast-induced nephropathy. © 2016 John Wiley & Sons Ltd.

  19. Application of stereological estimates in patients with severe head injuries using CT and MR scanning images

    DEFF Research Database (Denmark)

    Eriksen, Nanna; Rostrup, E; Andersen, K

    2010-01-01

    Severe brain damage is often followed by serious complications. Quantitative measurements, such as regional volume and surface area under various conditions, are essential for understanding functional changes in the brain and assessing prognosis. The affected brain tissue is variable, hence tradi...

  20. The skin-to-calyx distance measured by renal ct scan and ultrasound

    Directory of Open Access Journals (Sweden)

    Chen Jen Shan

    2014-04-01

    Full Text Available PurposeWe developed a stereotactic device to guide the puncture for percutaneous nephrolithotripsy, which uses the distance from the target calyx to its perpendicular point on skin (SCD to calculate the needle´s entry angle. This study seeks to validate the use of measurements obtained by ultrasound (US and computerized tomography (CT for needle´s entry angle calculation and to study factors that may interfere in this procedure.Materials and MethodsHeight, weight, abdominal circumference, CT of the urinary tract in dorsal decubitus (DD and ventral decubitus (VD, and US of the kidneys in VD were obtained from thirty-five renal calculi patients. SCD obtained were compared and correlated with body-mass index (BMI.ResultsBMI was 28.66 ± 4.6 Kg/m2. SCD on CT in DD was 8.40 ± 2.06cm, in VD was 8.32 ± 1.95cm, in US was 6.74 ± 1.68cm. SCD measured by US and CT were statistically different (p < 0.001, whereas between CT in DD and VD were not. SCD of the lower calyx presented moderate correlation with BMI.ConclusionSCD obtained by CT in ventral and dorsal decubitus may be used for calculation of the needle´s entry angle. SCD obtained by US cannot be used. A rule for the correlation between BMI and the SCD could not be determined.

  1. Reducing the throughput time of the diagnostic track involving CT scanning with computer simulation

    Energy Technology Data Exchange (ETDEWEB)

    Lent, Wineke A.M. van, E-mail: w.v.lent@nki.nl [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital (NKI-AVL), P.O. Box 90203, 1006 BE Amsterdam (Netherlands); University of Twente, IGS Institute for Innovation and Governance Studies, Department of Health Technology Services Research (HTSR), Enschede (Netherlands); Deetman, Joost W., E-mail: j.deetman@nki.nl [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital (NKI-AVL), P.O. Box 90203, 1006 BE Amsterdam (Netherlands); Teertstra, H. Jelle, E-mail: h.teertstra@nki.nl [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital (NKI-AVL), P.O. Box 90203, 1006 BE Amsterdam (Netherlands); Muller, Sara H., E-mail: s.muller@nki.nl [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital (NKI-AVL), P.O. Box 90203, 1006 BE Amsterdam (Netherlands); Hans, Erwin W., E-mail: e.w.hans@utwente.nl [University of Twente, School of Management and Governance, Dept. of Industrial Engineering and Business Intelligence Systems, Enschede (Netherlands); Harten, Wim H. van, E-mail: w.v.harten@nki.nl [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital (NKI-AVL), P.O. Box 90203, 1006 BE Amsterdam (Netherlands); University of Twente, IGS Institute for Innovation and Governance Studies, Department of Health Technology Services Research (HTSR), Enschede (Netherlands)

    2012-11-15

    Introduction: To examine the use of computer simulation to reduce the time between the CT request and the consult in which the CT report is discussed (diagnostic track) while restricting idle time and overtime. Methods: After a pre implementation analysis in our case study hospital, by computer simulation three scenarios were evaluated on access time, overtime and idle time of the CT; after implementation these same aspects were evaluated again. Effects on throughput time were measured for outpatient short-term and urgent requests only. Conclusion: The pre implementation analysis showed an average CT access time of 9.8 operating days and an average diagnostic track of 14.5 operating days. Based on the outcomes of the simulation, management changed the capacity for the different patient groups to facilitate a diagnostic track of 10 operating days, with a CT access time of 7 days. After the implementation of changes, the average diagnostic track duration was 12.6 days with an average CT access time of 7.3 days. The fraction of patients with a total throughput time within 10 days increased from 29% to 44% while the utilization remained equal with 82%, the idle time increased by 11% and the overtime decreased by 82%. The fraction of patients that completed the diagnostic track within 10 days improved with 52%. Computer simulation proved useful for studying the effects of proposed scenarios in radiology management. Besides the tangible effects, the simulation increased the awareness that optimizing capacity allocation can reduce access times.

  2. The skin-to-calyx distance measured by renal ct scan and ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Shan, Chen Jen; Mazzucchi, Eduardo; Payão, Fabio; Gomes, Andrea Cavalanti; Baroni, Ronaldo Hueb; Torricelli, Fabio Cesar; Vicentini, Fabio Carvalho; Srougi, Miguel [Hospital das Clínicas, University of Sao Paulo Medical School, Sao Paulo, SP (Brazil)

    2014-03-15

    Purpose: We developed a stereotactic device to guide the puncture for percutaneous nephrolithotripsy, which uses the distance from the target calyx to its perpendicular point on skin (