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Sample records for pretreatment ct scan

  1. Head CT scan

    Science.gov (United States)

    ... CT; Cranial CT; CT scan - skull; CT scan - head; CT scan - orbits; CT scan - sinuses; Computed tomography - ... Head CT is done in the hospital or radiology center. You lie on a narrow table that ...

  2. CT Scan

    Science.gov (United States)

    ... ll likely be told to drink lots of fluids to help your kidneys remove the contrast material from your body. Results CT images are stored as electronic data files and are usually reviewed on a computer screen. A radiologist interprets these images and sends ...

  3. Pelvic CT scan

    Science.gov (United States)

    CAT scan - pelvis; Computed axial tomography scan - pelvis; Computed tomography scan - pelvis; CT scan - pelvis ... Abnormal results may be due to: Abscess (collection of pus) Bladder stones Broken bone Cancer Diverticulitis

  4. CT scanning in meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Wardle, Stephan; Carty, Helen (Royal Liverpool Children' s Hospital, Liverpool (United Kingdom). Department of Radiology)

    12 pediatric cases of acute meningitis were reviewed retrospectively. Findings on CT scan were compared with the clinical course and resulting neurological sequelae. Complications detected by CT scanning include subdural effusion, empyema, hydrocephalus, cerebral atrophy, oedema and infarction. The CT scan results adequately correlated with neurological signs in most cases. Infarction was a reliable indicator of neurological sequelae. Cerebral atrophy alone, however, did not correlate well with the clinical sequelae. (author). 19 refs.; 5 figs.; 6 tabs.

  5. 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.

  6. Cervical spine CT scan

    Science.gov (United States)

    ... your provider if you take the diabetes medicine metformin (Glucophage). You may need to take extra steps ... to contrast dye Birth defect if done during pregnancy CT scans expose you to more radiation than ...

  7. Leg CT scan

    Science.gov (United States)

    ... your provider if you take the diabetes medicine metformin (Glucophage). You may need to take extra steps ... to contrast dye Birth defect if done during pregnancy CT scans expose you to more radiation than ...

  8. Shoulder CT scan

    Science.gov (United States)

    ... your provider if you take the diabetes medicine metformin (Glucophage) because you may need to take extra ... to contrast dye Birth defect if done during pregnancy CT scans do expose you to more radiation ...

  9. Knee CT scan

    Science.gov (United States)

    ... your provider if you take the diabetes medicine metformin (Glucophage). You may need to take extra steps ... to contrast dye Birth defect if done during pregnancy CT scans give off more radiation than regular ...

  10. Arm CT scan

    Science.gov (United States)

    ... your provider if you take the diabetes drug metformin (Glucophage). You may need to take special steps ... to contrast dye Birth defect if done during pregnancy CT scans expose you to more radiation than ...

  11. Thoracic spine CT scan

    Science.gov (United States)

    ... Ma, MD, Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, CA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team. CT Scans Read more Spinal Cord Injuries Read more Spine ...

  12. Prediction of neoadjuvant radiation chemotherapy response and survival using pretreatment [{sup 18}F]FDG PET/CT scans in locally advanced rectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Ji-In; Ha, Seunggyun; Kim, Sang Eun [Seoul National University Bundang Hospital, Department of Nuclear Medicine, Seoul National University College of Medicine, Seongnam (Korea, Republic of); Kang, Sung-Bum; Oh, Heung-Kwon [Seoul National University Bundang Hospital, Department of Surgery, Seoul National University College of Medicine, Seongnam (Korea, Republic of); Lee, Keun-Wook [Seoul National University Bundang Hospital, Department of Internal Medicine, Seongnam (Korea, Republic of); Lee, Hye-Seung [Seoul National University Bundang Hospital, Department of Pathology, Seoul National University College of Medicine, Seongnam (Korea, Republic of); Kim, Jae-Sung [Seoul National University Bundang Hospital, Department of Radiation Oncology, Seongnam (Korea, Republic of); Lee, Ho-Young [Seoul National University Bundang Hospital, Department of Nuclear Medicine, Seoul National University College of Medicine, Seongnam (Korea, Republic of); Seoul National University, Cancer Research Institute, Seoul (Korea, Republic of)

    2016-03-15

    The aim of this study was to investigate metabolic and textural parameters from pretreatment [{sup 18}F]FDG PET/CT scans for the prediction of neoadjuvant radiation chemotherapy response and 3-year disease-free survival (DFS) in patients with locally advanced rectal cancer (LARC). We performed a retrospective review of 74 patients diagnosed with LARC who were initially examined with [{sup 18}F]FDG PET/CT, and who underwent neoadjuvant radiation chemotherapy followed by complete resection. The standardized uptake value (mean, peak, and maximum), metabolic volume (MV), and total lesion glycolysis of rectal cancer lesions were calculated using the isocontour method with various thresholds. Using three-dimensional textural analysis, about 50 textural features were calculated for PET images. Response to neoadjuvant radiation chemotherapy, as assessed by histological tumour regression grading (TRG) after surgery and 3-year DFS, was evaluated using univariate/multivariate binary logistic regression and univariate/multivariate Cox regression analyses. MVs calculated using the thresholds mean standardized uptake value of the liver + two standard deviations (SDs), and mean standard uptake of the liver + three SDs were significantly associated with TRG. Textural parameters from histogram-based and co-occurrence analysis were significantly associated with TRG. However, multivariate analysis revealed that none of these parameters had any significance. On the other hand, MV calculated using various thresholds was significantly associated with 3-year DFS, and MV calculated using a higher threshold tended to be more strongly associated with 3-year DFS. In addition, textural parameters including kurtosis of the absolute gradient (GrKurtosis) were significantly associated with 3-year DFS. Multivariate analysis revealed that GrKurtosis could be a prognostic factor for 3-year DFS. Metabolic and textural parameters from initial [{sup 18}F]FDG PET/CT scans could be indexes to assess

  13. CT scans in encephalitis

    International Nuclear Information System (INIS)

    Imanishi, Masami; Morimoto, Tetsuya; Iida, Noriyuki; Hisanaga, Manabu; Kinugawa, Kazuhiko

    1980-01-01

    Generally, CT scans reveal a decrease in the volume of the ventricular system, sylvian fissures and cortical sulci in the acute stage of encephalitis, and softening of the cerebral lobes with dilatation of the lateral ventricles and subarachnoidian dilated spaces in the chronic stage. We encountered three cases of encephalitis: mumps (case 1), herpes simplex (case 2), and syphilis (case 3). In case 1, brain edema was seen in the acute stage and brain atrophy in the chronic stage. In case 2, necrosis of the temporal pole, which is pathognomonic in herpes simplex encephalitis, was recognized. And in case 3, multiple lesions whose CT appearance was enhanced by contrast materials were found scattered over the whole brain. These lesions were diagnosed as inflammatory granuloma by histological examination. (author)

  14. Body CT (CAT Scan)

    Science.gov (United States)

    ... scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ... prescribed procedure with your doctor, the medical facility staff and/or your insurance provider to get a ...

  15. Spinal CT scan, 2

    International Nuclear Information System (INIS)

    Nakagawa, Hiroshi

    1982-01-01

    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. (Chiba, N.)

  16. CT scan of Parkinson's disease

    International Nuclear Information System (INIS)

    Konishi, Tetsuro; Noguchi, Sadako; Nishitani, Hiroshi; Kitano, Haruo; Ikegami, Yoshinori.

    1981-01-01

    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. (author)

  17. CT scan of pituitary adenomas

    International Nuclear Information System (INIS)

    Sakoda, K.; Mukada, K.; Yonezawa, M.; Matsumura, S.; Yoshimoto, H.; Mori, S.; Uozumi, T.

    1981-01-01

    CT scan is an extremely useful, almost harmless means of diagnosing pituitary adenomas. Growth hormone (GH)-secreting adenomas tend to have higher absorption coefficent in plain CT than the nonfunctioning and prolactin (PRL)-secreting adenomas. The absorption coefficent on contrast-enhanced CT does not identify the specific type of adenoma. Ring-like enhancement was observed in five nonfunctioning and four PRL-secreting adenomas with suprasellar extension, while cystic components were observed in four nonfunctioning and four PRL-secreting adenomas. In three of ten cases of PRL-secreting microadenomas, the site corresponding to the adenoma was not enhanced, whereas the normal pituitary was. A correlation exists between the size of PRL-secreting adenoma and the serum PRL level, but not between the size of GH-secreting adenomas and the serum GH level. (orig.)

  18. CT Scan in the uterine cervix cancer

    International Nuclear Information System (INIS)

    Sinistrero, G.; Sismondi, P.; Zola, P.; Giai, M.

    1986-01-01

    The use of CT Scan in the evaluation of local tumor spread in patients with carcinoma of the cervix is an interesting subject, but only few data can be gathered from the literature. From Jan. 1978 to Dec., 1981, 252 patients with carcinoma of the cervix have been studied. The correlation between CT Scan and clinical staging has been studied for tumor volume and extension to parametrium and vagina. A comparison has been made between CT Scan and lymphangiography for sensitivity and specificity. In patient with recurrence, the local tumor spread has been studied by CT Scan. These data have been compared with the data collected by traditional clinical radiological work-up. CT Scan proved to be better than traditional radiological examinations as for as tumor volume, tumor extension, nodal enlargement, hydronephroses are concerned; moreover the possibility of obtaining a tridimensional reconstruction of the tumor volume is useful in planning radiation treatments. On the contrary CT Scan failed to detect vaginal invasion and proved to be less effective in evaluating parametrial extension. CT Scan and lymphangiography are equivalent in detection and diagnosis of lymph node involvement. In patients with recurrences CT Scan gives the most of informations, while in patients clinically free of disease it seems to be useless [fr

  19. Diagnostic value of axial CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Kiuchi, Sousuke (Tsukuba Univ., Sakura, Ibaraki (Japan))

    1983-03-01

    Axial CT scan was used to investigate the radiological details of the temporal bone of 33 patients with chronic otitis media, secondary cholesteatoma, sensorineural hearing loss, Meniere disease, vertigo, facial spasm, and neoplasma. The axial scans showed anatomic details of the temporal bone, and at the same time clearly demonstrated the extent of the soft-tissue masses in the middle ears, as well as the destructions of the ossicles. Bone changes of the anterior walls of the epitympanum and external auditory meatus were more clearly demonstrated than by coronary CT scan. However, the axial scan had the disadvantages in demonstrating the stapes, crista transversa, and the mastoid portion of the facial canal.

  20. Evaluation strategies in CT scanning

    DEFF Research Database (Denmark)

    In this talk, dimensional measurement results using different measuring strategies applied in different inspection software packages for volume and surface data analysis are presented. The influence of the strategy on the dimensional measurement is determined by calculating the measurement...... uncertainty. This investigation includes measurements of two industrial items, an aluminum pipe connector and a plastic toggle, a hearing aid component. These are measured using a commercial CT scanner. Traceability is transferred using tactile and optical coordinate measuring machines, which are used...

  1. Optical-CT scanning of polymer gels

    International Nuclear Information System (INIS)

    Oldham, M

    2004-01-01

    The application of optical-CT scanning to achieve accurate high-resolution 3D dosimetry is a subject of current interest. The purpose of this paper is to provide a brief overview of past research and achievements in optical-CT polymer gel dosimetry, and to review current issues and challenges. The origins of optical-CT imaging of light-scattering polymer gels are reviewed. Techniques to characterize and optimize optical-CT performance are presented. Particular attention is given to studies of artifacts in optical-CT imaging, an important area that has not been well studied to date. The technique of optical-CT simulation by Monte-Carlo modeling is introduced as a tool to explore such artifacts. New simulation studies are presented and compared with experimental data

  2. 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....

  3. CT scan of bacterial and aseptic meningitis

    International Nuclear Information System (INIS)

    Takemoto, Kazumasa; Saiwai, Shigeo; Tamaoka, Koichi

    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 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. (author)

  4. 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.

  5. Incidental apical disease at CT scanning

    International Nuclear Information System (INIS)

    McLoud, T.C.; Satoh, K.; Shepard, J.O.; Moore, E.H.; Kosiuk, J.P.

    1990-01-01

    Apical caps are commonly noted on standard radiographs. This paper determines how often abnormalities in the extreme apex of the lung could be identified on CT scans obtained for other reasons. A total of 158 consecutive CT scans were reviewed prospectively. Excluded were patients with obvious upper lobe pleural or parenchymal disease. Apical abnormalities were identified in 74 (46.8%) of the 158 cases. The prevalence increased with age (19% in the 8-39-year age group and 82% in patients older than 80 years). Opacities were unilateral in 44.5% and bilateral in 55.5%. The most common abnormality was linear opacities (95%)

  6. Computer graphic display of cardiac CT scans

    International Nuclear Information System (INIS)

    Palmer, R.; Carlsson, E.

    1982-01-01

    In order to improve spatial conception and quantitative assessment of the cardiac structures based on cardiac computed tomography, methods for computer graphic display were developed. Excised hearts and living dogs with myocardial infarctions were subjected to CT scanning. The data on the scanner tapes were processed to provide isodensity plots, linear section plots, time-weighted integrated isodensity plots as well as topographical density displays and three-dimensional spatial reconstructions of single and multi-layer scans. (orig.)

  7. Contrast bolus technique with rapid CT scanning

    International Nuclear Information System (INIS)

    Arnold, H.; Kuehne, D.; Rohr, W.; Heller, M.

    1981-01-01

    Twenty-three patients complying with the clinical criteria for brain death were studied by contrast-enhanced CT. In all but one, the great intracranial vessels escaped visualization; accordingly, angiography demonstrated cerebral circulatory arrest. In the remaining case, faint enhancement of the circle of Willis corresponded to angiographic demonstration of the proximal segments of cerebral arteris. Neither in normal brain nor in dead brain did slow CT scanning disclose any postcontrast increase in parenchymal attenuation. An improved technique is proposed to demonstrate the transit of the contrast bolus by rapid CT with image splitting. If cerebral blood flow is preserved, the grey and white matter will enhance significantly following administration of contrast medium. Vice versa, the absence of enhancement confirms brain death, even in instances in which the great cerebral vessels are obscured by hemorrhage or other extensive lesions. Two additional cases of brain death were evaluated by rapid CT scanning. As to brain death, the technique obviates the need for angiography or radionuclide angiography, usually applied in prospective organ donors, because its informative content is superior to that of either method. The CT technique described affords a reliable and safe diagnosis of brain death, and can be interpreted easily. (orig.)

  8. Serial CT scannings in herpes simplex encephalitis

    International Nuclear Information System (INIS)

    Fukushima, Masashi; Sawada, Tohru; Kuriyama, Yoshihiro; Kinugawa, Hidekazu; Yamaguchi, Takenori

    1981-01-01

    Two patients with serologically confirmed herpes simplex encephalitis were studied by serial CT scannings. Case 1, a 60-year-old woman, was admitted to National Cardiovascular Center because of headache, fever, and attacks of Jacksonian seizure. Case 2, a 54-year-old man, was admitted because of fever, consciousness disturbance and right hemipare sis. Pleocytosis (mainly lymphocytes) and elevation of protein content in cerebrospinal fluid were observed in both cases. Both patients presented ''das apallische Syndrom'' one month after admission. The diagnosis of herpes simplex encephalitis was confirmed by typical clinical courses and by greater than fourfold rises in serum antibody titer for herpes simplex virus as well as that in cerebrospinal fluid in case 1. Characteristic CT findings observed in these two cases were summarized as follows: Within a week after the onset, no obvious abnormalities could be detected on CT scans (Case 1). Two weeks after the onset, a large low-density area appeared in the left temporal lobe and in the contralateral insular cortex with midline shift toward the right side (Case 2). One month later, an ill-defined linear and ring-like high-density area (Case 1), or a well-defined high-density area (Case 2), that was enhanced after contrast administration, was observed in the large low-density area in the temporal lobe. These findings were considered as characteristic for hemorrhagic encephalitis. These high-density areas disappeared two months later, however, widespread and intensified low-density areas still remained. In both cases, the basal ganglia and thalamus were completely spared on CT scans. From these observations, it can be concluded that serial CT scannings are quite useful for diagnosis of herpes simplex encephalitis. (author)

  9. CT-scanning in otolaryngology, 2

    International Nuclear Information System (INIS)

    Kusakari, Jun; Endo, Satomi; Hara, Akira

    1982-01-01

    Combined computerized tomography-sialography was performed in 28 patients with parotid tumors. Sialography was performed in the usual fashion. After confirming the presence of the contrast material within the parotid gland by X-ray, 4 to 5 scannings were done at the width of 10 mm below Repid's base line. With this procedure, the parotid gland was clearly demonstrated and the location of the tumor was shown as a shadow defect. Although the nature of the tumor, especially whether it was malignant or benign was difficult to predict, the CT-findings regarding the size and location of the tumor were completely coincident with the operative findings in all the cases. Accurate appraisal of the relation between the tumor and the facial nerve was possible in all but two cases. The preoperative information obtained from CT-scanning is extremely useful in the case of parotid tumor surgery. (author)

  10. Implementation of dual energy CT scanning

    International Nuclear Information System (INIS)

    Marshall, W.; Hall, E.; Doost-Hoseini, A.; Alvarez, R.; Macovski, A.; Cassel, D.

    1984-01-01

    A prereconstruction method for dual energy (PREDECT) analysis of CT scans is described. In theory, this method can (a) eliminate beam hardening and produce an accuracy comparable with monoenergetic scans and (b) provide the effective atomic number and electron density of any voxel scanned. The implementation proves these statements and eliminates some of the objectionable noise. A phantom was constructed with a cylindrical sleeve-like compartment containing known amounts of high atomic number material simulating a removable skull. Conventional scans, with and without this beam hardener, were done of a water bath containing tubes of high electron and high atomic number material. Dual energy scans were then done for PREDECT. To increase the effective separation of the low and high energy beams by using more appropriate tube filtration, a beam filter changer was fabricated containing erbium, tungsten, aluminum, and steel. Erbium, tungsten, and steel were used at high energy and aluminum, steel, and erbium at low energy for data acquisition. The reconstructions were compared visually and numerically for noise levels with the original steel only filtration. A decrease was found in noise down to approximately one-half the prior level when erbium/aluminum or tungsten/aluminum replaced the steel/steel filter. Erbium and tungsten were equally effective. Steel/erbium and steel/aluminum also significantly reduced image noise. The noise in the photoelectric (P) and Compton (C) images is negatively correlated. At any pixel, if the noise is positive in the P image, it is most probably negative in the C. Using this fact, the noise was reduced by postreconstruction processing

  11. CT SCAN EVALUATION OF PULMONARY NODULE

    Directory of Open Access Journals (Sweden)

    A. Ravi Kumar

    2016-06-01

    Full Text Available BACKGROUND Lung carcinomas are quite commonly diagnosed. Thanks to the ever increasing smokers’ population. Majority of the city dwellers are at a higher risk of having this disease when compared to the village counterparts. The stigma through which the person and the family have to undergo before confirming the diagnosis is enormous. So the radiographic methods of diagnosing the malignancies have to improve. Before confirming the diagnosis, the radiologists, the treating physicians should be somewhat confident about the diagnosis so as to prepare the patients and their relatives for the most probable diagnosis before the confirmatory report. The confirmatory procedures include the PET scan and the Histopathology. Both are time consuming procedures and in an economy like ours, finding a PET scanning centre is rather difficult. So the most probable diagnosis has to be thought of using minimal resource. This study puts in a sincere effort to understand and evaluate the pulmonary nodule when identified by a CT scan. This paper is intended to help the practicing radiologists and also make life easy for a practicing physician to identify correctly the lesions and also help the patients to prevent further progression of the disease. METHODS The study was a cross-sectional study. The sample size of the study consisted of thirty patients. CT scan was done in thirty patients who were identified to have lung nodules either by other mode of radiological studies or first time identified in a CT scan itself. The study was conducted in Fathima Institute of Medical Sciences, Kadapa. The study was conducted from 2014 to 2015. RESULT Non-solid nodules were more in number when compared to the solid nodules. All the non-solid nodules were confirmed to be adenomas. Eighty percent of the nodules which were more than 8 mm in size were confirmed to be malignant. One hundred percent of the spiculated border on CT was confirmed to be malignant. In the present study

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

    Science.gov (United States)

    ... Imaging Medical X-ray Imaging Full-Body CT Scans - What You Need to ... clinics and medical imaging facilities nationwide are touting a new service for health-conscious people: "Whole-body CT screening." ...

  13. The sensitivity of computed tomography (CT) scans in detecting trauma: are CT scans reliable enough for courtroom testimony?

    Science.gov (United States)

    Molina, D Kimberley; Nichols, Joanna J; Dimaio, Vincent J M

    2007-09-01

    Rapid and accurate recognition of traumatic injuries is extremely important in emergency room and surgical settings. Emergency departments depend on computed tomography (CT) scans to provide rapid, accurate injury assessment. We conducted an analysis of all traumatic deaths autopsied at the Bexar County Medical Examiner's Office in which perimortem medical imaging (CT scan) was performed to assess the reliability of the CT scan in detecting trauma with sufficient accuracy for courtroom testimony. Cases were included in the study if an autopsy was conducted, a CT scan was performed within 24 hours before death, and there was no surgical intervention. Analysis was performed to assess the correlation between the autopsy and CT scan results. Sensitivity, specificity, positive predictive value, and negative predictive value were defined for the CT scan based on the autopsy results. The sensitivity of the CT scan ranged from 0% for cerebral lacerations, cervical vertebral body fractures, cardiac injury, and hollow viscus injury to 75% for liver injury. This study reveals that CT scans are an inadequate detection tool for forensic pathologists, where a definitive diagnosis is required, because they have a low level of accuracy in detecting traumatic injuries. CT scans may be adequate for clinicians in the emergency room setting, but are inadequate for courtroom testimony. If the evidence of trauma is based solely on CT scan reports, there is a high possibility of erroneous accusations, indictments, and convictions.

  14. Tomosynthesis using high speed CT scanning system

    International Nuclear Information System (INIS)

    Boyd, D.P.; Rutt, B.K.

    1988-01-01

    In a high-speed CT scanning system in which fan beams of radiation are generated by sweeping an electron beam along a target and collimated X-rays emitted by the target are received by an array of detectors after passing through a patient area between the target and the array of detectors, a method of obtaining a tomograph of a patient is described comprising the steps of sweeping the electron beam along the target, measuring radiation received at detector positions as the electron beam is swept along the target; moving the patient past the collimated X-rays, and combining measurements at the detector positions as correlated in time to positions of the patient and tomosynthesizing the tomograph from data for lines in the desired plane for the positions of the patient

  15. 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.

  16. Time factors associated with CT scan usage in trauma patients

    International Nuclear Information System (INIS)

    Fung Kon Jin, P.H.P.; Geene, A.R. van; Linnau, K.F.; Jurkovich, G.J.; Ponsen, K.J.; Goslings, J.C.

    2009-01-01

    Introduction: While computed tomography (CT) scan usage in acute trauma patients is currently part of the standard complete diagnostic workup, little is known regarding the time factors involved when CT scanning is added to the standard workup. An analysis of the current time factors and intervals in a high-volume, streamlined level-1 trauma center can potentially expose points of improvement in the trauma resuscitation phase. Materials and methods: During a 5-week period, data on current time factors involved in CT scanned trauma patients were prospectively collected. All consecutive trauma patients seen in the Emergency Department following severe trauma, or inter-hospital transfer following initial stabilizing elsewhere, and that underwent CT scanning, were included. Patients younger than 16 years of age were excluded. For all eligible patients, a complete time registration was performed, including admission time, time until completion of trauma series, time until CT imaging, and completion of CT imaging. Subgroup analyses were performed to differentiate severity of injury, based on ISS, and on primary or transfer presentations, surgery, and ICU admittance. Results: Median time between the arrival of the patient and completion of the screening X-ray trauma series was 9 min. Median start time for the first CT scan was 82 min. The first CT session was completed in a median of 105 min after arrival. Complete radiological workup was finished in 114 min (median). In 62% of all patients requiring CT scanning, a full body CT scan was obtained. Patients with ISS >15 had a significant shorter time until CT imaging and time until completion of CT imaging. Conclusion: In a high-volume level-1 trauma center, the complete radiological workup of trauma patients stable enough to undergo CT scanning, is completed in a median of 114 min. Patients that are more severely injured based on ISS were transported faster to CT, resulting in faster diagnostic imaging.

  17. CT scan assessment in salivary gland lithiasis diagnosis.

    Science.gov (United States)

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

    2018-04-01

    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.

  18. Spinal CT scan, 1. Cervical and thoracic spines

    Energy Technology Data Exchange (ETDEWEB)

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

    1982-01-01

    Methods of CT of the cervical and thoracic spines were explained, and normal CT pictures of them were described. Spinal CT was evaluated in comparison with other methods in various spinal diseases. Plain CT revealed stenosis due to spondylosis or ossification of posterior longitudinal ligament and hernia of intervertebral disc. CT took an important role in the diagnosis of spinal cord tumors with calcification and destruction of the bone. CT scan in combination with other methods was also useful for the diagnosis of spinal injuries, congenital anomalies and infections.

  19. 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.

  20. Radiation dose differences between thoracic radiotherapy planning CT and thoracic diagnostic CT scans

    International Nuclear Information System (INIS)

    Sanderud, A.; England, A.; Hogg, P.; Fosså, K.; Svensson, S.F.; Johansen, S.

    2016-01-01

    Purpose: To compare the absorbed dose from computed tomography (CT) in radiotherapy planning (RP-CT) against those from diagnostic CT (DG-CT) examinations and to explore the possible reasons for any dose differences. Method: Two groups of patients underwent CT-scans of the thorax with either DG-CT (n = 55) or RP-CT (n = 55). Patients from each group had similar weight and body mass index (BMI) and were divided into low (<25) and high BMI (>25). Parameters including CTDIvol, DLP and scan-length were compared. Results: The mean CTDIvol and DLP values from RP-CT (38.1 mGy, 1472 mGy cm) are approximately four times higher than for DG-CT (9.63 mGy, 376.5 mGy cm). For low BMI group, the CTDIvol in the RP-CT scans (36.4 mGy) is 6.3 times higher than the one in the DG-CT scans (5.8 mGy). For the high BMI group, the CTDIvol in the RP-CT (39.6 mGy) is 2.5 times higher than the one in the DG-CT scans (15.8 mGy). In the DG-CT scans a strong negative linear correlation between noise index (NI) and mean CTDIvol was observed (r = −0.954, p = 0.004); the higher NI, the lower CTDIvol. This was not the case in the RP-CT scans. Conclusion: The absorbed radiation dose is significantly higher and less BMI dependent for RP-CT scans compared to DG-CT. Image quality requirements of the examinations should be researched to ensure that radiation doses are not unnecessarily high. - Highlights: • The radiation dose differences in diagnostic vs. radiotherapy planning thorax CT. • The average effective dose given to radiotherapy planning patients are 30.0 mSv. • The average effective dose given to diagnostic patients are 7.7 mSv. • The CTDIvol is less BMI dependent for radiotherapy planning thorax CT scans compared to diagnostic scans.

  1. Cushing's syndrome with an apparently normal CT scan

    International Nuclear Information System (INIS)

    Vlahos, L.; Strigaris, K.; Aliferopoulos, D.; Pontifex, G.

    1981-01-01

    A case of Cushing's syndrome is described in which the CT scan was considered as normal. The diagnosis was established with selective venography and blood sampling and was verified surgically. (orig.)

  2. Airway tree reconstruction in expiration chest CT scans facilitated by information transfer from corresponding inspiration scans.

    Science.gov (United States)

    Bauer, Christian; Eberlein, Michael; Beichel, Reinhard R

    2016-03-01

    Analysis and comparison of airways imaged in pairs of inspiration and expiration lung CT scans provides important information for quantitative assessment of lung diseases like chronic obstructive pulmonary disease. However, airway tree reconstruction in expiration CT scans is a challenging problem. Typically, only a low number of airway branches are found in expiration scans, compared to inspiration scans. To detect more airways in expiration CT scans, the authors introduce a novel airway reconstruction approach and assess its performance. The method requires a pair of inspiration and expiration CT scans and utilizes information from the inspiration scan to facilitate reconstructing the airway tree in the expiration lung CT scan. First, an initial airway tree (high confidence) and airway candidates (limited confidence) are reconstructed in the expiration scan by utilizing a 3D graph-based reconstruction method. Then, the 3D airway tree is reconstructed in the inspiration scan. Second, correspondences between expiration and inspiration tree structures are identified by utilizing a novel hierarchical tree matching algorithm that utilizes a local CT image-based similarity criterion. Third, the tree information from the inspiration airway tree is used to select expiration candidates, resulting in the final expiration tree structure. The approach was evaluated on a diverse set of 40 scan pairs and compared to the baseline method, which utilizes only the expiration CT scan. The proposed method produced a significant (p inspiration and expiration airway trees, which can facilitate label transfer between airway trees and quantitative assessment of change in airways. The approach can be adapted to facilitate airway reconstruction in several longitudinal lung CT scans by means of mutual information transfer.

  3. Delayed intracerebral hemorrhage as demonstrated by CT scanning

    International Nuclear Information System (INIS)

    Brunetti, J.; Zingesser, L.; Dunn, J.; Rovit, R.L.; Saint Vincent's Hospital and Medical Center, New York

    1979-01-01

    Three patients are presented who developed delayed intracerebral hematomas after head injury. Two patients had essentially negative CT scans on admission and developed intracerebral hematomas within 24 h after injury. They required surgical treatment and had fatal outcomes. The third patient presented with an epidural hematoma on CT scan, developed an intracerebral hematoma 48 h after evacuation of the epidural hematoma, and did well with conservative management. (orig.) [de

  4. Dynamic CT scan in cerebral infarction

    International Nuclear Information System (INIS)

    Kobayashi, Shigeki; Oka, Nobuo; Mitsuhashi, Hiromitsu

    1984-01-01

    Forty-two dynamic CT studies were performed on 27 patients with cerebral infarction (11 to 75 years of age), and perfusion patterns of low density areas on plain CT were evaluated. The initial studies were performed 1.5 hours to 60 days after acute onset. The following results were obtained. 1) The perfusion pattern in the low density area on plain CT varies among patients at any periods after onset, ranging from absent perfusion pattern to hyperfusion pattern. No consisitent perfusion pattern was obtained at any given time after onset. 2) Repeat dynamic CT revealed that the perfusion pattern in the low density area changed with time variously. 3) The perfusion pattern or change of perfusion pattern did not correlate with outcome of the patient. 4) At an acute stage, when no abnormal findings were obtained on plain CT, dynamic CT revealed abnormal perfusion pattern, enabling early diagnosis of cerebral infarction and estimation of blood perfusion in the infarcted area. In determining the treatment for the cerebral infarction at an acute stage, it is important to know the condition of the blood perfusion in the infarcted area. For the patients in whom recanalization has already taken place, mannitol or steroid might be effective, providing protection against severe brain edema and hemorrhagic infarction. On the other hand, if recanalization has not taken place, revascularization therapy might be worth trying within 6 hours since the onset. It has been said that ischemic brain damage may not be reversed by the revascularization after 6 hours. Dynamic CT is safe, less invasive, convenient and very useful for early diagnosis of the cerebral infarction and determination of the treatment at the acute stage. (J.P.N.)

  5. 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.

  6. Radon Space Dose Optimization in Repeat CT Scanning.

    Science.gov (United States)

    Shamul, N; Joskowicz, L

    2017-12-01

    We present a new method for on-line radiation dose optimization in repeat computer tomography (CT) scanning. Our method uses the information of the baseline scan during the repeat scanning to significantly reduce the radiation dose without compromising the repeat scan quality. It automatically registers the patient to the baseline scan using fractional scanning and detects in sinogram space the patient regions where changes have occurred without having to reconstruct the repeat scan image. It scans only these regions in the patient, thereby considerably reducing the necessary radiation dose. It then completes the missing values of the sparsely sampled repeat scan sinogram with those of the fully sampled baseline sinogram in regions where no changes were detected and computes the repeat scan image by standard filtered backprojection reconstruction. Experiments on a patient scan with simulated changes yield a mean recall of 98% using <19% of a full dose. Experiments on real CT scans of an abdomen phantom produce similar results, with a mean recall of 94.5% and only 14.4% of a full dose more than the theoretical optimum. As hardly any changed rays are missed, the reconstructed images are practically indistinguishable from a full dose scan. Our method successfully detects small, low contrast changes and produces an accurate repeat scan reconstruction using three times less radiation than an image space baseline method.

  7. Classication Methods for CT-Scanned Carcass Midsections

    DEFF Research Database (Denmark)

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

    2011-01-01

    Computed tomography (CT) has successfully been applied in medical environments for decades. In recent years CT has also made its entry to the industrial environments, including the slaughterhouses. In this paper we investigate classication methods for an online CT system, in order to assist...... 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...

  8. Clinical evaluation of multislice CT scan for the temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Ogawa, Hiroshi; Ohtani, Iwao; Oishi, Tsuyoshi; Baba, Yoko; Kano, Makoto; Sagawa, Yuichi [Fukushima Medical Coll. (Japan)

    2001-05-01

    Rapid progress of medical technology has contributed greatly to improve imaging of the temporal bone. The ability of high resolution computerized tomography (HRCT) provided exquisite contrast and spatial resolution. As a result, HRCT has been the current method of choice for the delineation of fine structures of the temporal born. Helical scanning is one of the techniques in HRCT, and it has attracted a great deal of attention as an innovative diagnostic imaging technique for X-ray CT. The helical CT system is superior to conventional CT system in requiring a much shorter examination time, and enables us to get many more continuous images. We have been using this system since 1992. Since 1999 we have been able to use the new helical CT system. This system is able to perform the multislice scanning, and to obtain the thin slice thickness images as compared with the conventional helical CT system. (author)

  9. Volumetric measurement of the maxillary sinus by coronal CT scan

    International Nuclear Information System (INIS)

    Ikeda, Atsuko

    1996-01-01

    The volume of the maxillary sinus was estimated by coronal CT scan. The purpose of this study was to compare the estimated volume of the normal maxillary sinus with that of the inflamed maxillary sinus. Patients were classified following evaluation by CT scan of the paranasal sinuses into 3 categories. Group A (n=12): Patients suffered from headache, facial pain and epistaxis, but CT scans of their nasal cavity and paranasal sinus were within normal limits without inflammatory change. Group B (n=69): Patients with bilateral chronic maxillary sinusitis, CT scans of whom showed inflammatory changes in both maxillary sinuses. All of the patients in this group underwent sinus surgery after coronal CT scans. Group C (n=14): Patients with unilateral chronic maxillary sinusitis, CT scans of whom showed inflammatory change in unilateral maxillary sinuses. CT scans of these patients were measured by Plannimeter to take the area of each image of the maxillary sinus. Consecutively imaged areas were summated by integral calculus to obtain an estimate of the sinus volume. The mean maxillary sinus volume in the affected sinuses was significantly smaller than those in the contralateral normal sinuses (p<0.05, Wilcoxon-test). The various volumes of the maxillary sinuses and the developmental cause were discussed. Comparison of groups A with B suggested three distinct patterns; the maxillary sinus volume has decreased due to inflammatory changes in the bone. The small sinuses have a tendency to develop chronic inflammatory change. The aeration in the maxillary sinus may be decreased when anatomic variations that may obstruct the ethmoid infundibulum exist. (K.H.)

  10. Volumetric measurement of the maxillary sinus by coronal CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Atsuko [Tokyo Medical and Dental Univ. (Japan). School of Medicine

    1996-08-01

    The volume of the maxillary sinus was estimated by coronal CT scan. The purpose of this study was to compare the estimated volume of the normal maxillary sinus with that of the inflamed maxillary sinus. Patients were classified following evaluation by CT scan of the paranasal sinuses into 3 categories. Group A (n=12): Patients suffered from headache, facial pain and epistaxis, but CT scans of their nasal cavity and paranasal sinus were within normal limits without inflammatory change. Group B (n=69): Patients with bilateral chronic maxillary sinusitis, CT scans of whom showed inflammatory changes in both maxillary sinuses. All of the patients in this group underwent sinus surgery after coronal CT scans. Group C (n=14): Patients with unilateral chronic maxillary sinusitis, CT scans of whom showed inflammatory change in unilateral maxillary sinuses. CT scans of these patients were measured by Plannimeter to take the area of each image of the maxillary sinus. Consecutively imaged areas were summated by integral calculus to obtain an estimate of the sinus volume. The mean maxillary sinus volume in the affected sinuses was significantly smaller than those in the contralateral normal sinuses (p<0.05, Wilcoxon-test). The various volumes of the maxillary sinuses and the developmental cause were discussed. Comparison of groups A with B suggested three distinct patterns; the maxillary sinus volume has decreased due to inflammatory changes in the bone. The small sinuses have a tendency to develop chronic inflammatory change. The aeration in the maxillary sinus may be decreased when anatomic variations that may obstruct the ethmoid infundibulum exist. (K.H.)

  11. CT Scan of NASA Booster Nozzle

    Energy Technology Data Exchange (ETDEWEB)

    Schneberk, D; Perry, R; Thompson, R

    2004-07-27

    We scanned a Booster Nozzle for NASA with our 9 meV LINAC, AmSi panel scanner. Three scans were performed using different filtering schemes and different positions of the nozzle. The results of the scan presented here are taken from the scan which provided the best contrast and lowest noise of the three. Our inspection data shows a number of indications of voids in the outer coating of rubber/carbon. The voids are mostly on the side of the nozzle, but a few small voids are present at the ends of the nozzle. We saw no large voids in the adhesive layer between the Aluminum and the inner layer of carbon. This 3D inspection data did show some variation in the size of the adhesive layer, but none of the indications were larger than 3 pixels in extent (21 mils). We have developed a variety of contour estimation and extraction techniques for inspecting small spaces between layers. These tools might work directly on un-sectioned nozzles since the circular contours will fit with our tools a little better. Consequently, it would be useful to scan a full nozzle to ensure there are no untoward degradations in data quality, and to see if our tools would work to extract the adhesive layer.

  12. Prognostic Value and Reproducibility of Pretreatment CT Texture Features in Stage III Non-Small Cell Lung Cancer

    International Nuclear Information System (INIS)

    Fried, David V.; Tucker, Susan L.; Zhou, Shouhao; Liao, Zhongxing; Mawlawi, Osama; Ibbott, Geoffrey; Court, Laurence E.

    2014-01-01

    Purpose: To determine whether pretreatment CT texture features can improve patient risk stratification beyond conventional prognostic factors (CPFs) in stage III non-small cell lung cancer (NSCLC). Methods and Materials: We retrospectively reviewed 91 cases with stage III NSCLC treated with definitive chemoradiation therapy. All patients underwent pretreatment diagnostic contrast enhanced computed tomography (CE-CT) followed by 4-dimensional CT (4D-CT) for treatment simulation. We used the average-CT and expiratory (T50-CT) images from the 4D-CT along with the CE-CT for texture extraction. Histogram, gradient, co-occurrence, gray tone difference, and filtration-based techniques were used for texture feature extraction. Penalized Cox regression implementing cross-validation was used for covariate selection and modeling. Models incorporating texture features from the 33 image types and CPFs were compared to those with models incorporating CPFs alone for overall survival (OS), local-regional control (LRC), and freedom from distant metastases (FFDM). Predictive Kaplan-Meier curves were generated using leave-one-out cross-validation. Patients were stratified based on whether their predicted outcome was above or below the median. Reproducibility of texture features was evaluated using test-retest scans from independent patients and quantified using concordance correlation coefficients (CCC). We compared models incorporating the reproducibility seen on test-retest scans to our original models and determined the classification reproducibility. Results: Models incorporating both texture features and CPFs demonstrated a significant improvement in risk stratification compared to models using CPFs alone for OS (P=.046), LRC (P=.01), and FFDM (P=.005). The average CCCs were 0.89, 0.91, and 0.67 for texture features extracted from the average-CT, T50-CT, and CE-CT, respectively. Incorporating reproducibility within our models yielded 80.4% (±3.7% SD), 78.3% (±4.0% SD), and 78

  13. Prognostic Value and Reproducibility of Pretreatment CT Texture Features in Stage III Non-Small Cell Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Fried, David V. [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas (United States); Tucker, Susan L. [Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Zhou, Shouhao [Division of Quantitative Sciences, Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Liao, Zhongxing [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Mawlawi, Osama [Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas (United States); Ibbott, Geoffrey [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas (United States); Court, Laurence E., E-mail: LECourt@mdanderson.org [Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Graduate School of Biomedical Sciences, The University of Texas Health Science Center at Houston, Houston, Texas (United States)

    2014-11-15

    Purpose: To determine whether pretreatment CT texture features can improve patient risk stratification beyond conventional prognostic factors (CPFs) in stage III non-small cell lung cancer (NSCLC). Methods and Materials: We retrospectively reviewed 91 cases with stage III NSCLC treated with definitive chemoradiation therapy. All patients underwent pretreatment diagnostic contrast enhanced computed tomography (CE-CT) followed by 4-dimensional CT (4D-CT) for treatment simulation. We used the average-CT and expiratory (T50-CT) images from the 4D-CT along with the CE-CT for texture extraction. Histogram, gradient, co-occurrence, gray tone difference, and filtration-based techniques were used for texture feature extraction. Penalized Cox regression implementing cross-validation was used for covariate selection and modeling. Models incorporating texture features from the 33 image types and CPFs were compared to those with models incorporating CPFs alone for overall survival (OS), local-regional control (LRC), and freedom from distant metastases (FFDM). Predictive Kaplan-Meier curves were generated using leave-one-out cross-validation. Patients were stratified based on whether their predicted outcome was above or below the median. Reproducibility of texture features was evaluated using test-retest scans from independent patients and quantified using concordance correlation coefficients (CCC). We compared models incorporating the reproducibility seen on test-retest scans to our original models and determined the classification reproducibility. Results: Models incorporating both texture features and CPFs demonstrated a significant improvement in risk stratification compared to models using CPFs alone for OS (P=.046), LRC (P=.01), and FFDM (P=.005). The average CCCs were 0.89, 0.91, and 0.67 for texture features extracted from the average-CT, T50-CT, and CE-CT, respectively. Incorporating reproducibility within our models yielded 80.4% (±3.7% SD), 78.3% (±4.0% SD), and 78

  14. CT scanning of blunt trauma to bowel and mesentery

    International Nuclear Information System (INIS)

    Federle, M.P.; Griffiths, B.G.; Donohue, J.H.; Minagi, H.

    1986-01-01

    In a 6-year period, 1,500 consecutive CT scans were performed for the evaluation of blunt abdominal trauma. The patient population included 25 patients with a preoperative diagnosis of mesenteric or bowel injury. The preoperative diagnosis was proved correct in 23 cases. An additional 12 patients were diagnosed from CT findings as having bowel or mesenteric injuries, but did not undergo laparotomy. Of the patients who underwent operation, bowel wall thickening, intraperitoneal fluid, or both were noted on CT in all cases but one. Less frequently noted CT signs of bowel or mesenteric injury included extraluminal gas (seven cases) and extravasated contrast material (one). Both of these signs were regarded as indications for surgery, as were hematomas in the bowel wall or mesentery when accompanied by substantial amounts of intraperitoneal fluid. The importance of meticulous scanning technique and photography is emphasized. Potential sources of error in the assessment of bowel or mesenteric injuries are described

  15. Value of CT scan in synovial diseases

    Energy Technology Data Exchange (ETDEWEB)

    Tamisier, J.N.; Regent, D.; Thomas, P.; Pere, P.; Gaucher, A.; Capesius, P.

    1986-02-01

    The authors have developed a technique of CT arthroscan which, by the use of a gas or opaque contrast medium, is able to demonstrate the synovial structures of the knee, the shoulder and the hip. Among the essential indications, they include the demonstration of neoplasia of the synovium and the evaluation of the pannus in rheumatoid arthritis. Their secondary indications include the demonstration of fluid effusions in the hip, the precise evaluation of hyperostotic lesions in the same joint, the detection of ossification phenomena in the capsule of the inter-apophyseal joints in ankylosing spondylitis and, in some cases, following negative or doubtful arthrography for the detection of synovial plica. They also recall the usefulness or the arthroscan in the diagnosis of lesions of the labrum glenoidale.

  16. Sacrococcygeal teratoma showed a large cyst on CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, Kazuhiro; Suzuki, Noriyuki; Nishimura, Satoshi; Mori, Yoshimasa; Yamashita, Toshinori

    1984-05-01

    A newborn case with a sacrococcygeal teratoma is reported. A female baby had been noted at birth to have a small hairy pigmented skin lesion over her sacral region. She had shown acute obstructive ileus and bilateral hydronephrosis before long. A benign teratoma with a large cyst was demonstrated on ultra sound echogram and CT scan. The tumor was apparent externally but the predominant mass was intra-pelvic and extended into the retroperitoncal cavity of abdomen. Sacrococcygeal teratoma is uncommon but early diagnosis and surgery is necessary for aquiring good prognosis because it is almost benign. Abdominal CT scan is very worthy and required for diagnosis of the sacrococcygeal teratoma and the differential diagnosis of anterior myelomenigocele and congenital dermal sinus, etc. When a newborn baby is recognized a skin lesion over the sacral region, even though it is mild, CT scan will be necessary for the correct diagnosis, especially in female cases. (author).

  17. CT-scanning of ancient Greenlandic Inuit temporal bones

    International Nuclear Information System (INIS)

    Homoe, P.; 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 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.)

  18. 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.).

  19. 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.

  20. Serial CT scans in a case of meningeal myelomatosis

    International Nuclear Information System (INIS)

    Shimatsu, Akira; Tanaka, Satoru

    1985-01-01

    A case of Ig D myeloma with meningeal myelomatosis is reported. A 64-year-old man, who complained of fatigue and loss of appetite, had nuchal rigidity, bilateral sixth nerve palsy, and choked disks. His cerebrospinal fluid contained plasma cells and a monoclonal protein band identical with that in the serum. CT scans showed, in the bilateral subdural spaces, brain edema and enhanced masses which disappeared after successful chemotherapy. Meningeal involvement in multiple myeloma is a rare occurrence. A cytologic examination of the cerebrospinal fluid and CT scans were valuable in this case. (author)

  1. CT-scanning of ancient Greenlandic Inuit temporal bones

    DEFF Research Database (Denmark)

    Homøe, P; Lynnerup, N; Videbaek, H

    1992-01-01

    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....

  2. 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 SUV mean 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 the

  3. CT scan imaging in cervical infections

    International Nuclear Information System (INIS)

    Marsot-Dupuch, K.; Janklewicz, Ph.; Chabolle, F.

    1988-01-01

    Infections of face and neck represent serious and potentially life threatening conditions that are sometimes difficult to differentiate from neoplasic tumours, especially in subacute clinical forms. Conventional radiographic techniques offer interest for cervical masses, except Ultra-Sonographic examen, in sites regarding vascular axes, but carries little value for evaluating their spread the into different cervical spaces. On the other hand, C.T. is valuable to precise the location and the extent and to determine its inflammatory nature by studying the fats and the aponeurosis around it. It helps in the analysis of associated adjacent signs: soft tissue swelling, extensive obliteration of adjacent fats, swelling of cervical aponeurosis, thickening of adjacent muscles. These findings are documented by the study of fourteen patients, admitted in St-Antopine hospital. All abcesses, except one, were easy to diagnose because of their low central attenuation. False negative cases are possible and noted by other authors. So, in absence of response to appropriate therapy, surgery is necessary to eliminate a misdiagnosed abcess. Furthermore, it's sometimes possible to suspect an etiology (foreign body, tuberculosis) [fr

  4. Adult head CT scans: the uncertainties of effective dose estimates

    International Nuclear Information System (INIS)

    Gregory, Kent J.; Bibbo, Giovanni; Pattison, John E.

    2008-01-01

    Full Text: CT scanning is a high dose imaging modality. Effective dose estimates from CT scans can provide important information to patients and medical professionals. For example, medical practitioners can use the dose to estimate the risk to the patient, and judge whether this risk is outweighed by the benefits of the CT examination, while radiographers can gauge the effect of different scanning protocols on the patient effective dose, and take this into consideration when establishing routine scan settings. Dose estimates also form an important part of epidemiological studies examining the health effects of medical radiation exposures on the wider population. Medical physicists have been devoting significant effort towards estimating patient radiation doses from diagnostic CT scans for some years. The question arises: How accurate are these effective dose estimates? The need for a greater understanding and improvement of the uncertainties in CT dose estimates is now gaining recognition as an important issue (BEIR VII 2006). This study is an attempt to analyse and quantify the uncertainty components relating to effective dose estimates from adult head CT examinations that are calculated with four commonly used methods. The dose estimation methods analysed are the Nagel method, the ImpaCT method, the Wellhoefer method and the Dose-Length Product (DLP) method. The analysis of the uncertainties was performed in accordance with the International Standards Organisation's Guide to the Expression of Uncertainty in Measurement as discussed in Gregory et al (Australas. Phys. Eng. Sci. Med., 28: 131-139, 2005). The uncertainty components vary, depending on the method used to derive the effective dose estimate. Uncertainty components in this study include the statistical and other errors from Monte Carlo simulations, uncertainties in the CT settings and positions of patients in the CT gantry, calibration errors from pencil ionization chambers, the variations in the organ

  5. Synchronized control of spiral CT scan for security inspection device

    International Nuclear Information System (INIS)

    Wang Jue; Jiang Zenghui; Wang Fuquan

    2008-01-01

    In security inspection system of spiral CT, the synchronization between removing and rotating, and the scan synchronization between rotating and sampling influence quality of image reconstruction, so it is difficulty and important that how to realize synchronized scan. According to the controlling demand of multi-slice Spiral CT, the method to realize synchronized scan is given. a synchronized control system is designed, in which we use a industrial PC as the control computer, use magnetic grids as position detectors, use alternating current servo motor and roller motor as drivers respectively drive moving axis and rotating axis. This method can solve the problem of synchronized scan, and has a feasibility and value of use. (authors)

  6. A Study for Reappearance According to the Scan Type, the CT Scanning by a Moving Phantom

    International Nuclear Information System (INIS)

    Choi, Jae Hyock; Jeong, Do Hyeong; Choi, Gye Suk; Jang, Yo Jong; Kim, Jae Weon; Lee, Hui Seok

    2007-01-01

    CT scan shows that significant tumor movement occurs in lesions located in the proximity of the heart, diaphragm, and lung hilus. There are differences concerning three kinds of type to get images following the Scan type called Axial, Helical, Cine (4D-CT) mode, when the scanning by CT. To know how each protocol describe accurately, this paper is going to give you reappearance using the moving phantom. To reconstruct the movement of superior-inferior and anterior-posterior, the manufactured moving phantom and the motor following breathing were used. To distinguish movement from captured images by CT scanning, a localizer adhered to the marker on the motor. The moving phantom fixed the movement of superior-inferior upon 1.3 cm /1 min. The motor following breathing fixed the movement of anterior-posterior upon 0.2 cm /1 min. After fixing each movement, CT scanning was taken by following the CT protocols. The movement of A localizer and volume-reappearance analyzed by RTP machine. Total volume of a marker was 88.2 cm 3 considering movement of superior-inferior. Total volume was 184.3 cm 3 . Total volume according to each CT scan protocol were 135 cm 3 by axial mode, 164.9 cm 3 by helical mode, 181.7 cm 3 by cine (4D-CT) mode. The most closely describable protocol about moving reappearance was cine mode, the marker attached localizer as well. CT scan should reappear concerning a exact organ-description and target, when the moving organ is being scanned by three kinds of CT protocols. The cine (4D-CT) mode has the advantage of the most highly reconstructible ability of the three protocols in reappearance of the marker using a moving phantom. The marker on the phantom has always regular motion but breathing patients don't move like a phantom. Breathing education and devices setting patients were needed so that images reconstruct breathing as exactly as possible. Users should also consider that an amount of radiation to patients is being bombed.

  7. Determination of CT number and density profile of binderless, pre-treated and tannin-based Rhizophora spp. particleboards using computed tomography imaging and electron density phantom

    Energy Technology Data Exchange (ETDEWEB)

    Yusof, Mohd Fahmi Mohd, E-mail: mfahmi@usm.my; Hamid, Puteri Nor Khatijah Abdul; Tajuddin, Abdul Aziz [School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia); Bauk, Sabar [School of Distance Education, Universiti Sains Malaysia, 11800 Penang (Malaysia); Hashim, Rokiah [School of Industrial Technologies, Universiti Sains Malaysia, 11800 Penang (Malaysia)

    2015-04-29

    Plug density phantoms were constructed in accordance to CT density phantom model 062M CIRS using binderless, pre-treated and tannin-based Rhizophora Spp. particleboards. The Rhizophora Spp. plug phantoms were scanned along with the CT density phantom using Siemens Somatom Definition AS CT scanner at three CT energies of 80, 120 and 140 kVp. 15 slices of images with 1.0 mm thickness each were taken from the central axis of CT density phantom for CT number and CT density profile analysis. The values were compared to water substitute plug phantom from the CT density phantom. The tannin-based Rhizophora Spp. gave the nearest value of CT number to water substitute at 80 and 120 kVp CT energies with χ{sup 2} value of 0.011 and 0.014 respectively while the binderless Rhizphora Spp. gave the nearest CT number to water substitute at 140 kVp CT energy with χ{sup 2} value of 0.023. The tannin-based Rhizophora Spp. gave the nearest CT density profile to water substitute at all CT energies. This study indicated the suitability of Rhizophora Spp. particleboard as phantom material for the use in CT imaging studies.

  8. Determination of CT number and density profile of binderless, pre-treated and tannin-based Rhizophora spp. particleboards using computed tomography imaging and electron density phantom

    Science.gov (United States)

    Yusof, Mohd Fahmi Mohd; Hamid, Puteri Nor Khatijah Abdul; Bauk, Sabar; Hashim, Rokiah; Tajuddin, Abdul Aziz

    2015-04-01

    Plug density phantoms were constructed in accordance to CT density phantom model 062M CIRS using binderless, pre-treated and tannin-based Rhizophora Spp. particleboards. The Rhizophora Spp. plug phantoms were scanned along with the CT density phantom using Siemens Somatom Definition AS CT scanner at three CT energies of 80, 120 and 140 kVp. 15 slices of images with 1.0 mm thickness each were taken from the central axis of CT density phantom for CT number and CT density profile analysis. The values were compared to water substitute plug phantom from the CT density phantom. The tannin-based Rhizophora Spp. gave the nearest value of CT number to water substitute at 80 and 120 kVp CT energies with χ2 value of 0.011 and 0.014 respectively while the binderless Rhizphora Spp. gave the nearest CT number to water substitute at 140 kVp CT energy with χ2 value of 0.023. The tannin-based Rhizophora Spp. gave the nearest CT density profile to water substitute at all CT energies. This study indicated the suitability of Rhizophora Spp. particleboard as phantom material for the use in CT imaging studies.

  9. Determination of CT number and density profile of binderless, pre-treated and tannin-based Rhizophora spp. particleboards using computed tomography imaging and electron density phantom

    International Nuclear Information System (INIS)

    Yusof, Mohd Fahmi Mohd; Hamid, Puteri Nor Khatijah Abdul; Tajuddin, Abdul Aziz; Bauk, Sabar; Hashim, Rokiah

    2015-01-01

    Plug density phantoms were constructed in accordance to CT density phantom model 062M CIRS using binderless, pre-treated and tannin-based Rhizophora Spp. particleboards. The Rhizophora Spp. plug phantoms were scanned along with the CT density phantom using Siemens Somatom Definition AS CT scanner at three CT energies of 80, 120 and 140 kVp. 15 slices of images with 1.0 mm thickness each were taken from the central axis of CT density phantom for CT number and CT density profile analysis. The values were compared to water substitute plug phantom from the CT density phantom. The tannin-based Rhizophora Spp. gave the nearest value of CT number to water substitute at 80 and 120 kVp CT energies with χ 2 value of 0.011 and 0.014 respectively while the binderless Rhizphora Spp. gave the nearest CT number to water substitute at 140 kVp CT energy with χ 2 value of 0.023. The tannin-based Rhizophora Spp. gave the nearest CT density profile to water substitute at all CT energies. This study indicated the suitability of Rhizophora Spp. particleboard as phantom material for the use in CT imaging studies

  10. 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.

  11. 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.

  12. Serial CT scans and Menkes' kinky hair disease

    International Nuclear Information System (INIS)

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

    1988-01-01

    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 μ g/dl, while the serum ceruloplasmin level was 3.2 mg/dl. He exhibited severe developmental failure. At 4 years of age, he died. (author)

  13. CT scanning may adversely influence choice of surgery in paediatric ...

    African Journals Online (AJOL)

    Kurt

    SA JOURNAL OF RADIOLOGY • July 2005. CT scanning may adversely influence choice of surgery in paediatric papillary thyroid carcinoma - a note of caution. S Andronikou. MB BCh, FCRad (Diag) (SA), FRCR (Lond). Formerly: Department of Paediatric Radiology. Red Cross Children's Hospital and. University of Cape ...

  14. Correlation between osteoporosis and skin thickness on CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Tae An; Song, Sun Wha; Lee, Dong Hoon; Kim, Bum Jin; Kim, Yoon Hee; Shinn, Young Rock; Kim, Youn Kil; Lee, Eun Jung; Cho, Song Mee; Son, Sang Bum [The Catholic Univ. College of Medicine, Seoul (Korea, Republic of)

    1998-11-01

    The purpose of this study was to evaluate the relationship between osteoporosis and skin thickness as shown by CT scanning. Eighty-six women with osteoporosis (mean age, 52) and 51 normal controls (mean age, 50) participated in the study. For a quantitative CT examinations, a CT scanner (Somatom Plus, Siemens) was used. Osteoporosis was defined as present when spinal bone mineral density was more than 2.5 standard deviations below young normal density, as determined by quantitative CT. Patients with endocrinologic, malignant or collagen disease and undergoing antimetabolite or steroid therapy were excluded. The thickness of back skin was retrospectively measured at the third lumbar vertebra level, as seen on CT films, using a conventional magnifier. For statistical analysis, Students't test and Spearman's rank correlation were used. On the basis of CT scans, the mean thickness of back skin in the osteoporotic group (0.50{+-}0.20mm) was signigicantly less than in normal control subjects(0.80{+-}0.23mm) (p<0.001). Significant correlation was observed between skin thickness and bone mineral density(r=3D0.523, p<0.0001). Sensitivity, specificity, accuracy, and positive and negative predictive values were measured as 76, 78, 76, 88, 62% with a cut-off value of 0.6 and 84, 61, 77, 81, 66% with a cut-off value of 0.7, respectively. The present study demonstrated that the thickness of back skin, as measured by CT scanning, is predictive of osteoporosis.=20.

  15. 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.

  16. 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

    of detectors and the corresponding noise characteristics. Stopping power maps were calculated for all three scans, and compared with the ground truth stopping power from the phantoms. Results. Proton CT gave slightly better stopping power estimates than the dual energy CT method, with root mean square errors...... 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...

  17. 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).

  18. Efficient ribcage segmentation from CT scans using shape features.

    Science.gov (United States)

    Xu, Ziyue; Bagci, Ulas; Jonsson, Colleen; Jain, Sanjay; Mollura, Daniel J

    2014-01-01

    Rib cage structure and morphology is important for anatomical analysis of chest CT scans. A fundamental challenge in rib cage extraction is varying intensity levels and connection with adjacent bone structures including shoulder blade and sternum. In this study, we present a fully automated 3-D algorithm to segment the rib cage by detection and separation of other bone structures. The proposed approach consists of four steps. First, all high-intensity bone structures are segmented. Second, multi-scale Hessian analysis is performed to capture plateness and vesselness information. Third, with the plate/vessel features, bone structures other than rib cage are detected. Last, the detected bones are separated from rib cage with iterative relative fuzzy connectedness method. The algorithm was evaluated using 400 human CT scans and 100 small animal images with various resolution. The results suggested that the percent accuracy of rib cage extraction is over 95% with the proposed algorithm.

  19. 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).

  20. 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.

  1. 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.

  2. Association between a quantitative CT scan measure of brain edema and outcome after cardiac arrest.

    Science.gov (United States)

    Metter, Robert B; Rittenberger, Jon C; Guyette, Francis X; Callaway, Clifton W

    2011-09-01

    Cerebral edema is one physical change associated with brain injury and decreased survival after cardiac arrest. Edema appears on computed tomography (CT) scan of the brain as decreased X-ray attenuation by gray matter. This study tested whether the gray matter attenuation to white matter attenuation ratio (GWR) was associated with survival and functional recovery. Subjects were patients hospitalized after cardiac arrest at a single institution between 1/1/2005 and 7/30/2010. Subjects were included if they had non-traumatic cardiac arrest and a non-contrast CT scan within 24h after cardiac arrest. Attenuation (Hounsfield Units) was measured in gray matter (caudate nucleus, putamen, thalamus, and cortex) and in white matter (internal capsule, corpus callosum and centrum semiovale). The GWR was calculated for basal ganglia and cerebrum. Outcomes included survival and functional status at hospital discharge. For 680 patients, 258 CT scans were available, but 18 were excluded because of hemorrhage (10), intravenous contrast (3) or technical artifact (5), leaving 240 CT scans for analysis. Lower GWR values were associated with lower initial Glasgow Coma Scale motor score. Overall survival was 36%, but decreased with decreasing GWR. The average of basal ganglia and cerebrum GWR provided the best discrimination. Only 2/58 subjects with average GWR<1.20 survived and both were treated with hypothermia. The association of GWR with functional outcome was completely explained by mortality when GWR<1.20. Subjects with severe cerebral edema, defined by GWR<1.20, have very low survival with conventional care, including hypothermia. GWR estimates pre-treatment likelihood of survival after cardiac arrest. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  3. CT scanning for diagnosing blunt ureteral and ureteropelvic junction injuries

    Directory of Open Access Journals (Sweden)

    Chu Peter

    2008-02-01

    Full Text Available Abstract Background Blunt ureteral and ureteropelvic (UPJ injuries are extremely rare and very difficult to diagnose. Many of these injuries are missed by the initial trauma evaluation. Methods Trauma registry data was used to identify all blunt trauma patients with ureteral or UPJ injuries, from 1 April 2001 to 30 November 2006. Demographics, injury information and outcomes were determined. Chart review was then performed to record initial clinical and all CT findings. Results Eight patients had ureteral or UPJ injuries. Subtle findings such as perinephric stranding and hematomas, and low density retroperitoneal fluid were evident on all initial scans, and prompted delayed excretory scans in 7/8 cases. As a result, ureteral and UPJ injuries were diagnosed immediately for these seven patients. These findings were initially missed in the eighth patient because significant associated visceral findings mandated emergency laparotomy. All ureteral and UPJ injuries have completely healed except for the case with the delay in diagnosis. Conclusion Most blunt ureteral and UPJ injuries can be identified if delayed excretory CT scans are performed based on initial CT findings of perinephric stranding and hematomas, or the finding of low density retroperitoneal fluid.

  4. Topographic diagnosis of parathyroid tumor by CT scan

    International Nuclear Information System (INIS)

    Fukunaga, Masao; Harioka, Toshio; Morita, Rikuji

    1981-01-01

    In order to detect the hyperfunctioning parathyroid gland(s), CT scan over the neck was performed in patients with parathyroid disorders, including 10 primary hyperparathyroidism (6 bone type, 3 stone type and 1 chemical type), 8 chronic renal failure on hemodialysis with renal osteodystrophy and 2 multiple endocrine adenomatosis (MEA) type I. We used a whole-body scanner (CT/T, GE). The slice thickness was 5 mm. All patients were scanned from the sternal notch upward to the larynx, and were enhanced by the administration of 30% DIP Conray for 15 min. The results of the topographic diagnosis were compared with the surgical findings. Precise preoperative localization was accomplished in 9/10 adenomas in primary hyperparathyroidism, 27/32 hyperplasias in secondary hyperparathyroidism, and 2/4 hyperplasias in MEA type I. The smallest lesion weighed 0.2 g. It was shown that CT scan over the neck was a noninvasive and simple method to define the localization of hyperfunctionig parathyroid gland(s). (author)

  5. 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)

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

    African Journals Online (AJOL)

    amnesia or witnessed disorientation in a patient with a GCS score of 13–15 who has suffered a traumatic event, the evaluation of minor head injury using. Computerized Axial Tomography Scan of the Head. (CT-head) has remained controversial.(1,3). CT–head is expensive, time consuming, strenuous to human resource ...

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

    African Journals Online (AJOL)

    Background: The burden of traumatic brain injury (TBI) is rising in developing countries. 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 ...

  8. Short communication: fused deposition models from CT scans.

    Science.gov (United States)

    Meakin, J R; Shepherd, D E T; Hukins, D W L

    2004-06-01

    Fused deposition modelling (FDM) is a new method for rapid prototyping, a technique that produces models of objects from computer files. The most commonly used rapid prototyping technique for medical applications is stereolithography, but FDM has several potential advantages. This paper is concerned with the accuracy of an FDM model of a sheep lumbar vertebra using data from a CT scan. The model and the original vertebra were compared by making measurements with vernier callipers and by laser scanning. Visually, the model reproduced the features of the original object; this conclusion was supported by a comparison of the laser scans. Discrepancies in measurements were comparable with those of models produced using other rapid prototyping techniques, demonstrating that FDM is a viable method for making models for clinical use.

  9. 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.

  10. 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.).

  11. CT scan and histology of experimental cerebral infarction

    International Nuclear Information System (INIS)

    Morimoto, Tetsuya; Sakaki, Toshisuke; Hori, Yutaka; Kyoi, Kikuo; Utsumi, Shozaburo.

    1983-01-01

    Cerebral infarction models were made by occluding the right middle cerebral artery (MCA) in 85 cats. Plain and enhanced CT scan were done at various interval after MCA occlusion. Follow-up period after MCA occlusion ranges from 6 hours to 35 days. Every model was studied histologically following CT scan.FCerebral infarction was divided into 4 different stages by characteristics on CT scan. First stage, named pre-edema stage, ranges from 6 hours to 24 hours after occlusion. Second stage, named edema stage, ranges from 12 hours to 5 days.FThird stage, named edema-diminishing stage, ranges from 4 days to 24 days. Forth stage, named cavity stage, ranges from 20 days to 35 days.FIn edema-diminishing stage, positive CE was identified in high percentage (81%). In these positive CE cats, infarcted region is identified as impaired carbon filling from the study of carbon perfusion. But in some cats, there is carbon deposit which indicates good microcirculation in the infarcted region. Fluorescein stain which indicates the region with BBB dysfunction extends not only in the positive CE region but also the surroundings of the positive CE region.FHistological characteristics of positive CE region is the appearance of dilatated capillaries and phagocytesFPositive CE region generally shows impaired carbon filling which indicates poor microcirculation.FAs so, intravascular component of iodine can not fully explain the positive CE. From the quantitative study of iodine, positive CE region contains very high level of iodine with comparison to the same region of the opposite hemisphere. The mechanism of positive CE depends not only on the intravascular component but also on the extravascular component of iodine. (J.P.N.)

  12. Three-dimensional-CT imaging of colorectal disease with thin collimation helical CT scanning

    International Nuclear Information System (INIS)

    Ogura, Toshihiro; Koizumi, Koichi; Sakai, Tatsuya; Kai, Shunkichi; Takatsu, Kazuaki; Maruyama, Masakazu

    1998-01-01

    We have conducted research on three-dimensional (3D)-CT-colonoscopy with thin collimation helical CT scanning over the past three years. This has lately become a subject of special interest. 3D-CT-colonoscopy has three kinds of visualizing methods depending on the threshold setting of CT values. The first one is the virtual endoscopy method which is displayed in a similar fashion to colonoscopic images. The second one is the air image method using the air in the digestive tract as a contrast medium. The third one is the pseudo-tract method which has characteristics of both virtual endoscopy and the air image method and visualizes in a shape of the digestive tract. The image visualized by 3D-CT-colonoscopy is similar to that of conventional colonoscopy and barium enema study, which is obtained with minimal invasion to patients. Obvious advanced carcinomas were easily visualized, and even a small flat polyp measuring 5 mm in size, was able to be observed retrospectively. The characteristics of our method are that we can easily make an examination in a short time and with little dependence on expert technique. Also patients have little discomfort compared to that experienced during colonoscopy and barium enema study. Important features are as follows; long calculation time, insufficient air insufflation, fecal material in the patient''s bowel, whole abdominal scan, and spatial resolution. In the near future, a multislice CT scanner system will have ability to overcome these problems. Therefore, 3D-CT-colonoscopy might be applied in the future for first line examination as a mass screening for colorectal carcinoma. (author)

  13. Primary laryngeal tuberculosis mimicking laryngeal carcinoma: CT scan features

    International Nuclear Information System (INIS)

    El Kettani, N Ech-Cherif; El Hassani, MR; Chakir, N; Jiddane, M

    2010-01-01

    Laryngeal tuberculosis is a rare disease. It is almost always associated with pulmonary tuberculosis. It occurs generally in adults without BCG vaccination or in cases of the acquired immune deficiency syndrome. On laryngoscopy and imaging, it often simulates laryngeal carcinoma, and confirmation is always histological. We report the case of a 36-year-old man who presented to our hospital with dysphonia and dysphagia. Laryngoscopy revealed a lesion of the left vocal cord and the ventricular strip. CT scan found focal, regular thickening of the left vocal cord, associated with irregular thickening of the posterior laryngeal wall. A biopsy confirmed the diagnosis of tuberculosis

  14. Diagnosis of anemia on CT scans of the thorax

    International Nuclear Information System (INIS)

    Corcoran, H.L.; Cook, D.E.; Proto, A.V.

    1986-01-01

    Visualization of the interventricular septum on nonenhanced CT scans of the thorax of patients with anemia has been illustrated in the literature and explained in terms of a density differential between the cardiac musculature and the blood of anemic patients (blood with a low hemoglobin level). There are no data on the frequency of visualization of the walls of the cardiac chambers, the aorta and its branches, the superior and inferior venae cavae, the brachiocephalic veins, the azygos arch, and so forth. Experience with 50 patients is reported in terms of the foregoing. Findings are correlated with the severity of the anemia, thereby indicating how commonly one may encounter such an appearance

  15. 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)

  16. Impact of the planning CT scan time on the reflection of the lung tumor motion

    International Nuclear Information System (INIS)

    Kim, Su San; Choi, Eun Kyung; Yi, Byong Yong; Ha, Sung Whan

    2004-01-01

    To evaluate the reflection of tumor motion according to the planning CT scan time. A model of N-shape, which moved along the longitudinal axis during the ventilation caused by a mechanical ventilator, was produced. The model was scanned by planning CT, while setting the relative CT scan time (T; CT scan time/ventilatory period) to 0.33, 0.50, 0.67, 0.75, 1.00, 1.33 T, and 1.53 T. In addition, three patients with non-small cell lung cancer who received stereotactic radiosurgery in the Department of Radiation Oncology, Asan Medical Center from 03/19/2002 to 05/21/2002 were scanned. Slow (IQ Premier, Picker, scan time 2.0 seconds per slice) and fast CT scans (Light Speed, GE Medical System, with a scan time of 0.8 second per slice) were performed for each patient. The magnitude of reflected movement of the N-shaped model was evaluated by measuring the transverse length, which reflected the movement of the declined bar of the model at each slice. For patients' scans, all CT data sets were registered using a stereotactic body frame scale with the gross tumor volumes delineated in one CT image set. The volume and three-dimensional diameter of the gross tumor volume were measured and analyzed between the slow and fast CT scans. The reflection degree of longitudinal movement of the model increased in proportion to the relative CT scan times below 1.00 T, but remained constant above 1.00 T. Assuming the mean value of scanned transverse lengths with CT scan time 1.00 T to be 100%, CT scans with scan times of 0.33, 0.50, 0.67, and 0.75 T missed the tumor motion by 30, 27, 20, and 7.0% respectively. Slow (scan time 2.0 sec) and Fast (scan time 0.8 sec) CT scans of three patients with longitudinal movement of 3, 5, and 10 mm measured by fluoroscopy revealed the increases in the diameter along the longitudinal axis increased by 6.3, 17, and 23% in the slow CT scans. As the relative CT scan time increased, the reflection of the respiratory tumor movement on planning CT also

  17. Investigation of normal intrathoracic trachea during dynamic CT scanning

    International Nuclear Information System (INIS)

    Pan Jishu; Yang Ming; Chen Qihang

    1998-01-01

    Purpose: To study the diameters and cross-sectional areas, as well as the shape of normal adult intrathoracic trachea during forced respiration in the Chinese. Materials and methods: 25 male volunteers were studied with dynamic CT, using electron beam CT scanner, at a level 2 cm above aortic arch, with 3 mm collimation. Ten 100-msec dynamic scans were obtained at 500-msec intervals during 5.5-second period as the volunteers performed forced inspiration and expiration vital capacity maneuvers. Results: The mean cross-sectional area, sagittal and coronal diameter of the trachea decreased dynamically from 228.36 mm 2 , 18.28 mm and 16.97 mm at end inspiration to 191.24 mm 2 , 15.62 mm and 16.19 mm at end expiration respectively. The average cross-section area decreased by 15.48% +- 9.6% between inspiration and expiration. The shape of trachea was rounded or elliptical on inspiration image and horseshoe shaped on end of expiration. Conclusion: The dynamic CT is ideally suited for the study of tracheal dimensions and shape during respiration maneuvers. Among the Chinese, if the cross-sectional area of trachea decrease by more than 50% from inspiration to expiration, diagnosis of tracheomalacia can be established

  18. Light scattering in optical CT scanning of Presage dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Y; Adamovics, J; Cheeseborough, J C; Chao, K S; Wuu, C S, E-mail: yx2010@columbia.ed

    2010-11-01

    The intensity of the scattered light from the Presage dosimeters was measured using a Thorlabs PM100D optical power meter (Thorlabs Inc, Newton, NJ) with an optical sensor of 1 mm diameter sensitive area. Five Presage dosimeters were made as cylinders of 15.2 cm, 10 cm, 4 cm diameters and irradiated with 6 MV photons using a Varian Clinac 2100EX. Each dosimeter was put into the scanning tank of an OCTOPUS' optical CT scanner (MGS Research Inc, Madison, CT) filled with a refractive index matching liquid. A laser diode was positioned at one side of the water tank to generate a stationary laser beam of 0.8 mm width. On the other side of the tank, an in-house manufactured positioning system was used to move the optical sensor in the direction perpendicular to the outgoing laser beam from the dosimeters at an increment of 1 mm. The amount of scattered photons was found to be more than 1% of the primary light signal within 2 mm from the laser beam but decreases sharply with increasing off-axis distance. The intensity of the scattered light increases with increasing light attenuations and/or absorptions in the dosimeters. The scattered light at the same off-axis distance was weaker for dosimeters of larger diameters and for larger detector-to-dosimeter distances. Methods for minimizing the effect of the light scattering in different types of optical CT scanners are discussed.

  19. Pre-treatment with a sinus node blockade, ivabradine, before coronary CT angiography

    DEFF Research Database (Denmark)

    Lambrechtsen, J; Egstrup, K

    2013-01-01

    To evaluate whether a simple pre-treatment regimen of sinus node inhibition by ivabradine taken at home for only 1 day resulted in a lower pre-scanning heart rate (HR) and reduced the need for intravenous beta-blockers (BB) prior to coronary computed tomography angiography (CTA).......To evaluate whether a simple pre-treatment regimen of sinus node inhibition by ivabradine taken at home for only 1 day resulted in a lower pre-scanning heart rate (HR) and reduced the need for intravenous beta-blockers (BB) prior to coronary computed tomography angiography (CTA)....

  20. Three-dimensional CT-angiogram by helical scanning CT for evaluating coronary bypass graft patency

    International Nuclear Information System (INIS)

    Machida, Masaharu; Suzuki, Miwako; Takahashi, Masanori; Kurosawa, Shinji

    1997-01-01

    In this study, we applied the three-dimensional (3D) reconstructed images of helical scanning computed tomography (CT) for patency evaluation of aortocoronary bypass grafts. From the experiments using a phantom model representing a vessel with a 2 mm inner diameter, an optimal scanning condition was established to reconstruct images with acceptable accuracy: X-ray beam width, 2 mm; velocity of patient's table movement 3 mm/sec: thickness of reconstructed two-dimensional (2D) image, 1 mm; lower cut-off CT number, 50-100 HU. A phantom model with pendulum movement was prepared to evaluate the effect of cardiac movement on the quality of reconstructed images. This model revealed that 3D reconstruction and image analysis were possible, although continuity of images was disrupted to some extent. Using the scanning condition determined from these phantom experiments, 3D images were prepared in 23 patients with aortocoronary grafts and compared with the findings of coronary angiography. Patency of bypass grafts was identified in 25 out of 27 saphenous vein grafts (SVG) and in 15 out of 19 internal mammary artery grafts (ITAG) (sensitivity in SVG and ITAG was 92.6% and 78.9%, respectively). Image reconstruction failed in all occluded arteries (specificity was 100% in both SVG and ITAG). These results clearly suggest that 3D-reconstructed images of helical CT is a useful method to evaluate the patency of aortocoronary bypass grafts non-invasively and accurately. (author)

  1. A study evaluating the dependence of the patient dose on the CT dose change in a SPECT/CT scan

    Science.gov (United States)

    Kim, Woo-Hyun; Kim, Ho-Sung; Dong, Kyung-Rae; Chung, Woon-Kwan; Cho, Jae-Hwan; Shin, Jae-Woo

    2012-07-01

    This study assessed ways of reducing the patient dose by examining the dependence of the patient dose on the CT (computed tomography) dose in a SPECT (single-photon emission computed tomography)/CT scan. To measure the patient dose, we used Precedence 16 SPECT/CT along with a phantom for the CT dose measurement (CT dose phantom kit for adult's head and body, Model 76-414-4150), a 100-mm ionization chamber (CT Ion Chamber) and an X-ray detector (Victoreen Model 4000M+). In addition, the patient dose was evaluated under conditions similar to those for an actual examination using an ImPACT (imaging performance assessment of CT scanners) dosimetry calculator in the Monte Carlo simulation method. The experimental method involved the use of a CT dose phantom to measure the patient dose under different CT conditions (kVp and mAs) to determine the CTDI (CT dose index) under each condition. An ImPACT dosimetry calculator was also used to measure CTDIw (CT dose index water ), CTDIv (CT dose index volume ), DLP (dose-length product), and effective dose. According to the patient dose measurements using the CT dose phantom, the CTDI showed an approximately 54 fold difference between when the maximum (140 kVp and 250 mAs) and the minimum dose (90 kVp and 25 mAs) was used. The CTDI showed a 4.2 fold difference between the conditions (120 kVp and 200 mAs) used mainly in a common CT scan and the conditions (120 kVp and 50 mAs) used mainly in a SPECT/CT scan. According to the measurement results using the dosimetry calculator, the effective dose showed an approximately 35 fold difference between the conditions for the maximum and the minimum doses, as in the case with the CT dose phantom. The effective dose showed a 4.1 fold difference between the conditions used mainly in a common CT scan and those used mainly in a SPECT/CT scan. This study examined the patient dose by reducing the CT dose in a SPECT/CT scan. As various examinations can be conducted due to the development of

  2. Pulmonary lobe separation in expiration chest CT scans based on subject-specific priors derived from inspiration scans.

    Science.gov (United States)

    Bauer, Christian; Eberlein, Michael; Beichel, Reinhard R

    2018-01-01

    Segmentation of pulmonary lobes in inspiration and expiration chest CT scan pairs is an important prerequisite for lobe-based quantitative disease assessment. Conventional methods process each CT scan independently, resulting typically in lower segmentation performance at expiration compared to inspiration. To address this issue, we present an approach, which utilizes CT scans at both respiratory states. It consists of two main parts: a base method that processes a single CT scan and an extended method that utilizes the segmentation result obtained on the inspiration scan as a subject-specific prior for segmentation of the expiration scan. We evaluated the methods on a diverse set of 40 CT scan pairs. In addition, we compare the performance of our method to a registration-based approach. On inspiration scans, the base method achieved an average distance error of 0.59, 0.64, and 0.91 mm for the left oblique, right oblique, and right horizontal fissures, respectively, when compared with expert-based reference tracings. On expiration scans, the base method's errors were 1.54, 3.24, and 3.34 mm, respectively. In comparison, utilizing proposed subject-specific priors for segmentation of expiration scans allowed decreasing average distance errors to 0.82, 0.79, and 1.04 mm, which represents a significant improvement ([Formula: see text]) compared with all other methods investigated.

  3. Varifocal mirror display of organ surfaces from CT scans

    International Nuclear Information System (INIS)

    Pizer, S.M.; Fuchs, H.; Bloomberg, S.H.; Li Ching Tsai; Heinz, E.R.

    1982-01-01

    A means will be presented of constructing a powerful varifocal mirror 3D display system with limited cost based on an ordinary color video digital display system. The importance of dynamic interactive control of the display of these images will be discussed; in particular, the design and usefulness of a method allowing real-time user-controlled motion of the 3D object being displayed will be discussed. Also, an effective method will be described of presenting images made of surfaces by the straightforward, automatic calculation of 3D edge strength, the ordering of the resulting voxels by edge strength, and the 3D grey-scale display of the top voxels on this ordered list. The application of these ideas to the 3D display of the intimal wall of the region of bifurcation of the carotid artery from 12-24 CT scans of the neck will be discussed

  4. Quantitative vertebral CT scan imaging in 105 women with osteoporosis

    Energy Technology Data Exchange (ETDEWEB)

    Laval-Jeantet, A.M.; Miravet, L.; Bergot, C.; Vernejoul, M.C. de; Kuntz, D.; Laval-Jentet, M.

    Quantitative vertebral CT scan imaging is a method developed to provide direct measurements of mineralization of vertebral body spongy tissue, and is presently the most precise procedure for the early detection of spinal osteoporosis. A fracture threshold has been defined below which are found 95% of patients with a crushed vertebra: it is situated at 70% of the value for mineralization normal for the age of patients. Patients with marked reductions in their level of mineralization can be kept under surveillance before the onset of fracture. In patients with vertebral collapses the density is correlated significantly with the number of crush fractures. In addition, measurement of vertebral spongy bone density has allowed the importance of the vertebral lesion to be determined in various osteoporotic disorders, including those with only cortical fractures, and in this way to differentiate them.

  5. Visuomotor ataxia. Clinical and CT scan studies in three cases

    Energy Technology Data Exchange (ETDEWEB)

    Hirose, Genjiro; Kawada, Junya; Oda, Rokuhei; Kitagawa, Yoshinobu; Kosoegawa, Hiroshi

    1985-03-01

    Three patients with visuomotor ataxia, a disorder of hand movement to grasp objects located in the periphery of the visual field, were studied clinically and neuroradiologically with conventional and reformatted CT scans. Visuomotor ataxia was noted in the hemifield contralateral to the parieto-occipital lesion with both hands regardless the side of the lesion in this study. No dominant hemisphere for visuomotor ataxia was noted. The responsible lesions for this disorder were overlapped at Broadmann's area 7, 18, 19 and their surrounded white matter including the connecting fibers to the contralateral hemisphere via the splenium of corpus callosum. No direct lesion was found in the angular gyrus (Broadmann area 39). Visuomotor ataxia was seen with both hands in our series and it can be explained by the disconnection of either or both of the direct and crossed long association fibers between visual association areas and motor association areas at the parieto-occipital junction. (author).

  6. Union of Scaphoid Waist Fractures Assessed by CT Scan.

    Science.gov (United States)

    Clementson, Martin; Jørgsholm, Peter; Besjakov, Jack; Björkman, Anders; Thomsen, Niels

    2015-02-01

    Background Union of a scaphoid fracture is difficult to assess on a standard series of radiographs. An unnecessary and prolonged immobilization is inconvenient and may impair functional outcome. Although operative treatment permits early mobilization, its influence on time to union is still uncertain. Purpose To assess union of scaphoid waist fractures based on computed tomography (CT) scan at 6 weeks, and to compare time to union between conservative treatment and arthroscopically assisted screw fixation. Patients and methods CT scan in the longitudinal axis of the scaphoid was used to provide fracture characteristics, and to assess bone union at 6 weeks in 65 consecutive patients with scaphoid waist fractures. In a randomized subgroup from this cohort with nondisplaced fractures, we compared time to union between conservative treatment (n = 23) and arthroscopically assisted screw fixation (n = 15). Results Overall, at 6 weeks we found a 90% union rate for non- or minimally displaced fracture treated conservatively, and 82% for those who underwent surgery. In the randomized subgroup of nondisplaced fractures, no significant difference in time to union was demonstrated between those treated conservatively and those who underwent surgery. The conservatively treated fractures from this subgroup with prolonged time to union (10 to 14 weeks) were comminuted, demonstrating a radial cortical or corticospongious fragment. Conclusion The majority of non- or minimally displaced scaphoid waist fractures are sufficiently treated with 6 weeks in a cast. Screw fixation does not reduce time to fracture union compared with conservative treatment. Level of Evidence level II, Therapeutic study.

  7. 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.

    2016-01-01

    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 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. PMID:26908205

  8. Intrapartum FHR monitoring and neonatal CT brain scan

    International Nuclear Information System (INIS)

    Takahashi, Yoshiki; Ukita, Masahiko; Nakada, Eizo

    1982-01-01

    The effect of fetal distress on the neonatal brain was investigated by neonatal CT brain scan, FHR monitoring and mode of delivery. This study involved 11 cases of full term vertex delivery in which FHR was recorded by fetal direct ECG during the second stage labor. All infants weighed 2,500 g or more. FHR monitoring was evaluated by Hon's classification. Neonatal brain edema was evaluated by cranial CT histgraphic analysis (Nakada's method). 1) Subdural hemorrhage was noted in 6 of 7 infants delivered by vacuum extraction or fundal pressure (Kristeller's method). 2) Intracranial hemorrhage was demonstrated in all of 3 infants with 5-min. Apgar score 7 or less. 3) Two cases with prolonged bradycardia and no variability had intraventricular or intracerebral hemorrhage which resulted in severe central nervous system damage. 4) The degree of neonatal brain edema correlated with 5-min. Apgar score. 5) One case with prolonged bradycardia and no variability resulted in severe neonatal brain edema. Four cases with variable deceleration and increased variability resulted in mild neonatal brain edema. Two cases with late deceleration and decreased variability resulted in no neonatal brain edema. (author)

  9. 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.

  10. Examination of CT-AEC when the positioning changes after planning of CT scanning

    International Nuclear Information System (INIS)

    Esaki, Tooru; Yamazaki, Shoichi

    2009-01-01

    CT-automatic exposure control (AEC) controls tube current collecting information of the subject from positioning shooting. Because of this, we consider that CT-AEC does not get to operate properly if the body position of the test subject changes after the positioning shooting. However, we often experience in body positions of test subjects after the positioning shooting. In cases like this, we measured by using a phantom again to see how they affect the tube current value and standard deviation (SD) value comparing them to the normal scan where a body position does not change. As a result of the measurement, there was an impact on CT-AEC that optimization of tube current becomes insufficient if the body position of a test subject changes. As the image quality is deteriorated and radiation exposure increases because of this, taking positioning shooting again is required on the part of users and it's desirable on the part of manufacturers to develop CT-AEC that can be controlled with high accuracy. (author)

  11. The value of contrast-enhanced CT scan in prediction of development of contusional hemorrhage

    International Nuclear Information System (INIS)

    Yokoyama, Kazuhiro; Kyoi, Kikuo; Sakaki, Toshisuke; Kinugawa, Kazuhiko; Morimoto, Tetsuya

    1983-01-01

    It is often experienced that even if there are no significant findings on the initial plain CT scan in the patient with cerebral contusion, the patient has thereafter a serious clinical course and requires emergency operation for so-called contusional hemorrhage. In order to predict of the development of contusional hemorrhage we performed contrast-enhanced CT scan at the time of patient's arrival within 12 hours after injury, if there was cerebral contusion on the initial plain CT scan, and repeated plain CT scan 24 hours after the contrast-enhanced CT scan. If enhancement was demonstrated on the contrastenhanced CT scan, we predicted the development of contusional hemorrhage and if not demonstrated, we predicted no more development of contusional hemorrhage and then we studied the correlation between the prediction and the plain CT 24 hours after the contrast-enhanced CT scan. The results were as follows: 1) The prediction was correct in 13 cases out of 16 cases in which the development of contusional hemorrhage was observed. In 18 cases where no development of contusional hemorrhage was observed, the prediction was correct without exception. 2) Most of the cases in which enhancement was demonstrated were ones examined not before 3 hours after injury. 3) The extent of enhancement shown on contrastenhanced CT scan was well consistent with that of contusional hemorrhage on the plain CT scan 24 hours after the contrast-enhanced CT scan. From these results, the contrast-enhanced CT scan in acute stage of head injury was considered to by very useful in prediction of the development of contusional hemorrhage. (author)

  12. Clinical Application of colored three-dimensional CT (3D-CT) for brain tumors using helical scanning CT (HES-CT)

    International Nuclear Information System (INIS)

    Ogura, Yuko; Katada, Kazuhiro; Fujisawa, Kazuhisa; Imai, Fumihiro; Kawase, Tsukasa; Kamei, Yoshifumi; Kanno, Tetsuo; Takeshita, Gen; Koga, Sukehiko

    1995-01-01

    We applied colored three-dimensional CT (colored 3D-CT) images to distinguish brain tumors from the surrounding vascular and bony structures using a work station system and helical scanning CT (HES-CT). CT scanners with a slip-ring system were employed (TCT-900S and X vigor). A slice thickness of 2 mm and bed speed of 2 mm/s were used. The volume of contrast medium injected was 60 to 70 ml. Four to 8 colors were used for the tissue segmentation on the workstation system (xtension) using the data transferred from HES-CT. Tissue segmentation succeeded on the colored 3D-CT images in all 13 cases. The relationship between the tumors and the surrounding structures were easily recognized. The technique was useful to simulate operative fields, because deep structures could be visualized by cutting and drilling the colored 3D-CT volumetric data. On the basis of our findings, we suggest that colored 3D-CT images should be used as a supplementary aid for preoperative simulation. (author)

  13. Eighteen cases of small breast cancer: a comparative study of mammography, CT scan and pathology

    International Nuclear Information System (INIS)

    Wu Yaopan; Lin Haogao; Cai Peiqiang; Ouyang Yi; Zhang Weizhang; Lu Bingui

    2003-01-01

    Objective: To improve the early diagnosis of breast cancer through a study of the mammography and CT findings of small breast cancer. Methods: The mammography and CT findings of 18 cases of small breast cancer (φ≤2.0 cm in diameter) were studied and compared with pathological results. Results: The diagnostic accuracy of CT and mammography was 83% and 61%, respectively. There was a statistical difference between both modalities (P<0.05), CT scan was superior to mammography. However, there was no difference between them when assessing the lesion arising in F-type breast. In detecting breast fine cluster of calcification, the sensitivity of mammography was better than CT scan. Conclusion: The patient suspected of small breast cancer should take mammography as the first evaluation. CT scan is reserved for the further investigation. The mammography combined with CT scan can improve the early diagnostic rate of breast cancer

  14. Childhood CT scans linked to leukemia and brain cancer later in life

    Science.gov (United States)

    Children and young adults scanned multiple times by computed tomography (CT), a commonly used diagnostic tool, have a small increased risk of leukemia and brain tumors in the decade following their first scan.

  15. Protocol optimization in chest CT scans of child

    International Nuclear Information System (INIS)

    Abrao L, L. T.; Amaral de O, F.; Prata M, A.; Bustos F, M.

    2017-10-01

    The dissemination of Computed Tomography (CT), a radiodiagnostic technique, has significant increase in the patient dose. In the last years, this technique has shown a high growth due to clinical cases of medical emergencies, neoplasm and pediatric traumas. Dose measurement is important to correlate with the deleterious effects of radiation on the organism and radiation future effects is related with stochastic risks due to tissue radiosensitivity, allied to the life expectancy of the child. In this work, a cylindrical phantom, representing an adult chest made of polymethylmethacrylate (PMMA), was used and a new born chest phantom with a shape oblong was developed based on the dimensions of a typical newborn. In a Ge CT scanner, Discovery model, with 64 channels, the central slice of the phantoms were irradiated successively in order to obtain dose measurements using an ionizing pencil camera. Based in the measurements, dose index was calculated (CTDI vol ). The radiological service chest protocol using a voltage of 120 kV was used for scanning 10 cm of the central area of the adult and newborn phantom, in helical mode. An acquisition of images was performed using this radiological service chest protocol to compare with the protocol optimized. In the newborn phantom was also used protocols optimized using a voltage of 120 and 80 kV. The voltage of 80 kV has the lowest dose index for the pediatric object phantom. This work allowed the comparison between absorbed dose variations by the pediatric phantom changing the X-ray tube supply voltage. This dose variation has shown how important is specific protocols for children. (Author)

  16. 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

  17. 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

    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...

  18. CT scanning in Australia: a report by the National Health Technology Advisory Panel

    International Nuclear Information System (INIS)

    1988-06-01

    An overview of trends in the usage of CT scanning in Australia is given and the areas of benefit and uncertainty associated with this technology are outlined. Numbers and distribution of CT units, costs of CT services, clinical applications, safety aspects and the effects of new developments are discussed. 54 refs., 5 figs., 18 tabs

  19. 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....

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

    African Journals Online (AJOL)

    Review of the CT scan showed severe narrowing of the nasopharynx and a tracheostomy was done under local anaesthesia prior to anaesthetizing the patient. No attempt would have been made to carry out a fibreoptic intubation if the CT scan had been studied earlier and the narrowing of the pharynx appreciated.

  1. a case of persistent left superior vena cava detected by post-contrast CT scan

    International Nuclear Information System (INIS)

    Sasaki, Fumio; Koga, Sukehiko; Takeuchi, Akira; Hattori, Yoshinobu; Ino, Akio

    1983-01-01

    A case of persistent left superior vena cava and large anastomosis between double superior vena cava was incidentally detected by post-contrast CT scans. This abnormal vein did not connect to the right atrium via coronary sinus. The usefulness for the diagnosis of post-contrast CT scans and RI venography should be emphasized. (author)

  2. 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...

  3. Importance of repeated CT scan in Fournier gangrene treatment: clinical case

    International Nuclear Information System (INIS)

    Ignatenco, Sergiu

    2011-01-01

    A patient of 53 years presented fever, swelling and erythema in the perineal region. After computed tomography (CT) was diagnosed Fournier gangrene. After aggressive surgical debridement postoperative evolution was unfavorable. Repeated CT scan trace spread of infection to new areas that led to new surgical debridement on time. Use of CT scan in the postoperative period allows assessment of the effectiveness of surgical debridement and spread of infection. This article presents CT scan images and the most important periods of intraoperative surgical intervention. (authors)

  4. Experimental study of abdominal CT scanning exposal doses adjusted on the basis of pediatric abdominal perimeter

    International Nuclear Information System (INIS)

    Wei Wenzhou; Zhu Gongsheng; Zeng Lingyan; Yin Xianglin; Yang Fuwen; Liu Changsheng

    2006-01-01

    Objective: To optimize the abdominal helical CT scanning parameters in pediatric patients and to reduce its radiation hazards. Methods: 60 canines were evenly grouped into 4 groups on the basis of pediatric abdominal perimeter, scanned with 110,150,190 and 240 mAs, and their qualities of canine CT images were analyzed. 120 pediafric patients with clinic suspected abdominal diseases were divided into 4 groups on the basis of abdominal perimeter, scanned by optimal parameters and their image qualities were analyzed. Results: After CT exposure were reduced, the percentages of total A and B were 90.9 % and 92.0 % in experimental canines and in pediatric patients, respectively. Compared with conventional CT scanning, the exposure and single slice CT dose index weighted (CTDIw) were reduced to 45.8%-79.17%. Conclusion: By adjusted the pediatric helical CT parameters basedon the of pediatric abdominal perimeter, exposure of patient to the hazards of radiation is reduced. (authors)

  5. Knowledge Representation Of CT Scans Of The Head

    Science.gov (United States)

    Ackerman, Laurens V.; Burke, M. W.; Rada, Roy

    1984-06-01

    We have been investigating diagnostic knowledge models which assist in the automatic classification of medical images by combining information extracted from each image with knowledge specific to that class of images. In a more general sense we are trying to integrate verbal and pictorial descriptions of disease via representations of knowledge, study automatic hypothesis generation as related to clinical medicine, evolve new mathematical image measures while integrating them into the total diagnostic process, and investigate ways to augment the knowledge of the physician. Specifically, we have constructed an artificial intelligence knowledge model using the technique of a production system blending pictorial and verbal knowledge about the respective CT scan and patient history. It is an attempt to tie together different sources of knowledge representation, picture feature extraction and hypothesis generation. Our knowledge reasoning and representation system (KRRS) works with data at the conscious reasoning level of the practicing physician while at the visual perceptional level we are building another production system, the picture parameter extractor (PPE). This paper describes KRRS and its relationship to PPE.

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

    International Nuclear Information System (INIS)

    Han, Man Seok; Kim, Tae Hyung; Lee, Seung Youl; Lee, Myeong Goo; Jeon, Min Cheol; Cho, Jae Hwan

    2012-01-01

    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.

  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. 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.

  9. Persistent SIRS and acute fluid collections are associated with increased CT scanning in acute interstitial pancreatitis.

    Science.gov (United States)

    Kamal, Ayesha; Faghih, Mahya; Moran, Robert A; Afghani, Elham; Sinha, Amitasha; Parsa, Nasim; Makary, Martin A; Zaheer, Atif; Fishman, Elliot K; Khashab, Mouen A; Kalloo, Anthony N; Singh, Vikesh K

    2018-01-01

    The use of computed tomography (CT) in acute pancreatitis (AP) continues to increase in parallel with the increasing use of diagnostic imaging in clinical medicine. To determine the factors associated with obtaining >1 CT scan in acute interstitial pancreatitis (AIP). Demographic and clinical data of all adult patients admitted between 1/2010 and 1/2015 with AP (AP) were evaluated. Only patients with a CT severity index (CTSI) ≤ 3 on a CT obtained within 48 h of presentation were included. A total of 229 patients were included, of whom 206 (90%) had a single CT and 23 (10%) had >1 CT during the first week of hospitalization. Patients undergoing >1 CT had significantly higher rates of acute fluid collection (AFC), persistent SIRS, opioid use ≥4 days, and persistent organ failure compared to those undergoing 1 CT (p SIRS (OR = 3.6, 95% CI 1.4-9.6, p = .01) and an AFC on initial CT (OR = 3.5, 95% CI 1.4-9, p = .009) were independently associated with obtaining >1 CT. An AFC on initial CT and persistent SIRS are associated with increased CT imaging in AIP patients. However, these additional CT scans did not change clinical management.

  10. Evaluation of delayed contrast-enhanced CT scan in diagnosing hilar cholangiocarcinoma

    International Nuclear Information System (INIS)

    Li Jianding; Liang Chenyang; Zhang Hua; Zhang Yuezhen; Li Rui

    2001-01-01

    Objective: To assess the diagnostic value of delayed CT contrast enhancement patterns in hilar cholangiocarcinoma based on two-phased dynamic incremental CT scanning. Methods: Fifty-two patients with suspected hilar tumor and bile duct obstruction underwent spiral CT scan. The scan time for one revolution of the X-ray tube was 1 second. To elucidate the delay time for optimal imaging, all proved cholangiocarcinoma with delayed (6, 8, 10, 15, 20, 30 minutes) post-equilibrium-phase contrast-enhanced CT scans were acquired with unenhanced, dynamic contrast-enhanced, and delayed images. Degree of delayed enhancement was compared with that of surrounding liver parenchyma. Results: (1) 8-15 minutes after IV injection of contrast material was the delay time for optimal imaging. (2) Of 29 cholangiocarcinomas, the early CT showed hypo-attenuating (lower than that of liver parenchyma) in 23 tumors, iso-attenuating (equal to that of the liver) in 4 tumors, and hyper-attenuating (higher than that of liver) in 2 tumors. The delayed CT scan showed iso-attenuating in 8 tumors, hyper-attenuating in 21 tumors, and no hypo-attenuating. Most of delay imaging of hilar cholangiocarcinoma may appear hyper-attenuating (U = -4.3073, P 2 = 9.09, P < 0.01). Conclusion: When assessing hilar tumor, delayed CT contrast enhancement patterns based on two-phase dynamic incremental CT scans is useful in the detection and characterization of hilar cholangiocarcinoma

  11. Wrist CT and three-dimensional reconstruction: Direct coronal versus transaxial scanning

    International Nuclear Information System (INIS)

    Biondetti, P.R.; Vannier, M.W.; Gilula, L.A.; Knapp, R.H.

    1986-01-01

    Because of its three-dimensional complexity, the wrist cannot be completely examined radiographically without CT. Complex carpal fractures, intercarpal and distal radioulnar dislocations or subluxations, late sequelae of trauma (nonunion, osteonecrosis, degenerative changes, infections), and the painful wrist with normal plain film and abnormal bone scan appearance have been evaluated with CT. In the majority of cases reported in the literature, the wrist was scanned by CT in the transaxial plane. The author compared direct transaxial and coronal CT scanning in 23 patients with wrist disorders. Axial sections were superior for distal radioulnar subluxation, hamate hook fractures, and for the ventral trapezial tubercle not shown on routine radiographs. Coronal scanning, performed using a specially designed wrist fixture, was preferable for most other wrist CT examinations. Coronal wrist CT offers perpendicular orientation for the majority of the carpal joints, anatomic display similar to that of plain film radiography, and fewer scans per wrist CT examination. Three-dimensional surface reconstruction wrist images were better when coronal rather than transaxial scans were used as input. Direct coronal CT should be the method of choice for most patients with wrist problems

  12. Impact of pretreatment noncontrast CT Alberta Stroke Program Early CT Score on clinical outcome after intra-arterial stroke therapy.

    Science.gov (United States)

    Yoo, Albert J; Zaidat, Osama O; Chaudhry, Zeshan A; Berkhemer, Olvert A; González, R Gilberto; Goyal, Mayank; Demchuk, Andrew M; Menon, Bijoy K; Mualem, Elan; Ueda, Dawn; Buell, Hope; Sit, Siu Po; Bose, Arani

    2014-03-01

    The efficacy of intra-arterial treatment remains uncertain. Because most centers performing IAT use noncontrast CT (NCCT) imaging, it is critical to understand the impact of NCCT findings on treatment outcomes. This study aimed to compare functional independence and safety among patients undergoing intra-arterial treatment stratified by the extent of ischemic change on pretreatment NCCT. The study cohort was derived from multicenter trials of the Penumbra System. Inclusion criteria were anterior circulation proximal occlusion, evaluable pretreatment NCCT, and known time to reperfusion. Ischemic change was quantified using the Alberta Stroke Program Early CT Score (ASPECTS) and stratified into 3 prespecified groups for comparison: 0 to 4 (most ischemic change) versus 5 to 7 versus 8 to 10 (least ischemic change). A total of 249 patients were analyzed: 40 with ASPECTS 0 to 4, 83 with ASPECTS 5 to 7, and 126 with ASPECTS 8 to 10. For ASPECTS 0 to 4, 5 to 7, and 8 to 10, respectively, good outcome (modified Rankin Scale score, 0-2) rates were 5%, 38.6%, and 46% (P<0.0001), and mortality rates were 55%, 28.9%, and 19% (P=0.0001). The only significant pairwise differences were between ASPECTS 0 to 4 and other groups. Symptomatic hemorrhage was more common with lower ASPECTS (P=0.02). Shorter time to reperfusion was significantly associated with better outcomes among patients with ASPECTS 8 to 10 (P=0.01). A similar relationship was seen for ASPECTS 5 to 7 but was not statistically significant. No such relationship was seen for ASPECTS 0 to 4. NCCT seems useful for excluding patients with the greatest burden of ischemic damage from futile intra-arterial treatment, which is unlikely to result in patient functional independence and increases the risk of hemorrhage.

  13. 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)

  14. 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...

  15. Direct sagittal CT scanning in the diagnosis of pituitary fossa tumours and posterior fossa pathology

    International Nuclear Information System (INIS)

    Podlas, H.

    1981-01-01

    Two independent methods are presented for multidirectional CT scanning of the brain using the Philips Tomoscan 300. The advantages in scanning pituitary fossa tumours and pathology of the posterior fossa are discussed. No additional software or modifications are required. Direct sagittal scanning is particularly advantageous for accurate assessment of the size of pituitary tumours and intrasellar lesions requiring surgical intervention or radiation therapy. (Auth.)

  16. 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.

  17. 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.

  18. Diagnostic value of CT scanning in neuromuscular diseases

    International Nuclear Information System (INIS)

    Bulcke, J.A.L.; Leuven Univ.; Herpels, V.

    1983-01-01

    The diagnosis of myopathies has become easier since the CT technique is available. In this article the possibilities of CT for diagnostic procedures of neuromuscular diseases are pointed out. Density measurements increase differentiation of atrophy or hypertrophy of muscles as well as other pathological changes. (orig.)

  19. Subarachnoid hemorrhage: role of subtraction CT angiography in etiological diagnosis and pretreatment planning.

    Science.gov (United States)

    Li, K; Wei, X; Lv, F; Li, Q; Xie, P

    2014-12-01

    Subarachnoid hemorrhage (SAH) is a deleterious cerebrovascular disorder that requires prompt etiological diagnosis. We wished to evaluate the diagnostic performance of the latest generation 3D subtraction CT angiography (CTA) in etiological diagnosis and pretreatment planning of patients with suspected SAH. A total of 88 patients were included in our study and underwent both 3D subtraction CTA and digital subtraction angiography (DSA) examinations. The 3D subtraction CTA images were reviewed by two independent readers who were blinded to the results of DSA. Sensitivity, specificity, positive and negative predictive values of 3D subtraction CTA were calculated on a per-patient basis. The possibility for surgical treatment was also evaluated based on information provided by CTA alone. According to DSA results, 72 patients were diagnosed with ruptured intracranial aneurysms, 5 patients with arteriovenous malformations, and no lesion was detected in 11 patients. Sensitivity, specificity, positive predictive value and negative predictive values of CTA for etiological evaluation of SAH were all 100%. Correct pretreatment decision was made in 67 of 70 patients based on the CTA measurements alone. THE results of our study indicate that 3D subtraction CTA is an accurate, fast and non-invasive imaging modality that is equal to DSA in etiological evaluation and pretreatment planning of patients with suspected SAH. It may replace DSA as the first step imaging method in patients with suspected SAH, while DSA should still be reserved for case of uncertainty.

  20. The Beatles, the Nobel Prize, and CT scanning of the chest.

    Science.gov (United States)

    Goodman, Lawrence R

    2010-01-01

    From its first test scan on a mouse, in 1967, to current medical practice, the CT scanner has become a core imaging tool in thoracic diagnosis. Initially financed by money from Beatles' record sales, the first patient scan was performed in 1971. Only 8 years later, a Nobel Prize in Physics and Medicine was awarded to Hounsfield and Cormack for their discovery. This article traces the history of CT scanner development and how each technical advance expanded chest diagnostic frontiers. Chest imaging now accounts for 30% of all CT scanning.

  1. Reduction in radiation doses from paediatric CT scans in Great Britain.

    Science.gov (United States)

    Lee, Choonsik; Pearce, Mark S; Salotti, Jane A; Harbron, Richard W; Little, Mark P; McHugh, Kieran; Chapple, Claire-Louise; Berrington de Gonzalez, Amy

    2016-01-01

    Although CT scans provide great medical benefits, concerns have been raised about the magnitude of possible associated cancer risk, particularly in children who are more sensitive to radiation than adults. Unnecessary high doses during CT examinations can also be delivered to children, if the scan parameters are not adjusted for patient age and size. We conducted the first survey to directly assess the trends in CT scan parameters and doses for paediatric CT scans performed in Great Britain between 1978 and 2008. We retrieved 1073 CT film sets from 36 hospitals. The patients were 0-19 years old, and CT scans were conducted between 1978 and 2008. We extracted scan parameters from each film including tube current-time product [milliampere seconds (mAs)], tube potential [peak kilovoltage (kVp)] and manufacturer and model of the CT scanner. We estimated the mean mAs for head and trunk (chest and abdomen/pelvis) scans, according to patient age (0-4, 5-9, 10-14 and 15-19 years) and scan year (trunk CTs: a 46% decline on an average from before 1990 to after 2000. Although mean mAs for trunk CTs did not vary with age before 1990, the value varied markedly by age, from 63 mAs for age 0-4 years compared with 315 mAs for those aged >15 years after 2000. No material changes in kVp were found. Estimated brain-absorbed dose from head CT scans decreased from 62 mGy before 1990 to approximately 30 mGy after 2000. For chest CT scans, the lung dose to children aged 0-4 years decreased from 28 mGy before 1990 to 4 mGy after 2000. We found that mAs for head and trunk CTs was approximately halved starting around 1990, and age-specific mAs was generally used for paediatric scans after this date. These changes will have substantially reduced the radiation exposure to children from CT scans in Great Britain. The study shows that mAs and major organ doses for paediatric CT scans in Great Britain began to decrease around 1990.

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

    International Nuclear Information System (INIS)

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

    2004-01-01

    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 cm 3 ). 4D CT can be used for 4D radiotherapy, respiration-gated radiotherapy, 'slow' CT acquisition and tumour motion studies

  3. 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.

  4. Aortic valve calcification - a commonly observed but frequently ignored finding during CT scanning of the chest.

    Science.gov (United States)

    Raju, Prashanth; Sallomi, David; George, Bindu; Patel, Hitesh; Patel, Nikhil; Lloyd, Guy

    2012-06-01

    To describe the frequency and severity of Aortic valve calcification (AVC) in an unselected cohort of patients undergoing chest CT scanning and to assess the frequency with which AVC was being reported in the radiology reports. Consecutive CT scan images of the chest and the radiological reports (December 2009 to May 2010) were reviewed at the district general hospital (DGH). AVC on CT scan was visually graded on a scale ranging from 0 to IV (0 = no calcification, IV = severe calcification). Total of 416 (232 male; 184 female) CT chest scans [Contrast enhanced 302 (72%), unenhanced 114 (28%)] were reviewed. Mean age was 70.55 ± 11.48 years. AVC in CT scans was identified in 95 of the 416 patients (22.83%). AVC classification was as follows: Grade I: 60 (63.15%), Grade II: 22 (23.15%), Grade III: 9 (9.47%), Grade IV: 4 (4.21%). Only one CT report mentioned AVC. Only 31 of 95 AVC had Transthoracic echocardiogram (TTE). The interval time between CT scan and TTE was variable.   Aortic valve calcification in CT chest scans is a common finding and studies have shown that it is strongly related to the presence and severity of aortic valve disease. As CT scans are considered as a valuable additional screening tool for detection of aortic stenosis, AVC should always be commented upon in the radiology reports. Furthermore, patients with at least Grade III and IV AVC should be sent for TTE. © 2012 Blackwell Publishing Ltd.

  5. 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 Sønde......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...

  6. Increased inspiratory pressure for reduction of atelectasis in children anesthetized for CT scan

    International Nuclear Information System (INIS)

    Sargent, Michael A.; Jamieson, Douglas H.; McEachern, Anita M.; Blackstock, Derek

    2002-01-01

    Background: Atelectasis is more frequent and more severe in children anesthetized for CT scan than it is in children sedated for CT scan.Objective: To determine the effect of increased inspiratory pressure on atelectasis during chest CT in anesthetized children. Materials and methods: Atelectasis on chest CT was assessed by two observers in three groups of patients. Group A comprised 13 children (26 lungs) anesthetized at inspiratory pressures up to and including 25 cm H 2 O. Group B included 11 children anesthetized at inspiratory pressures ≥30 cm H 2 O. Group C included 8 children under deep sedation. Results: Atelectasis was significantly more severe in group A than in groups B and C. There was no significant difference between groups B and C. Conclusion: An inspiratory pressure of 30 cm H 2 O is recommended for children anesthetized for CT scan of the chest. (orig.)

  7. Comparison between angiography and CT scan in the urologic field

    International Nuclear Information System (INIS)

    Fujioka, Toshio; Takao, Masaya; Odajima, Kunio; Nakamura, Hiroshi

    1988-01-01

    Seventy-five consecutive patients with urological diseases were examined preoperatively by means of computerized tomography and renal angiography. Classification of the diseases were 53 renal diseases which included renal cell carcinoma, sarcoma, cyst, renal bleeding, arteriovenous fistula, trauma, hydronephrosis and tuberculosis, 11 vesical diseases which included bladder tumor and endometriosis, 9 adrenal diseases which included primary aldosteronism, Cushing syndrome, pheochromocytoma, and metastatic tumor, and 1 case of intra-abdominal testes. For renal diseases, both angiography and CT were useful imaging tools. For vesical diseases, CT was a more useful imaging method but, for adrenal diseases, angiography was superior to CT. CT offers certain advantages over conventional techniques but, in the near future, it may be replaced by MRI. On the contrary, angiography will remain popular for a long time, because angiography is the only way to show which vessels feed organs. (author)

  8. CT scanning of the paranasal sinuses: axial helical CT with reconstruction in the coronal direction versus coronal helical CT.

    Science.gov (United States)

    Bernhardt, T M; Rapp-Bernhardt, U; Fessel, A; Ludwig, K; Reichel, G; Grote, R

    1998-08-01

    Paranasal sinuses of 52 patients with sinusitis, tumours or fibrous dysplasia were scanned. Axially acquired spiral data were obtained and reconstructed coronally. Four radiologists compared the two sets of images. They evaluated the diagnostic quality for visualization of the ostiomeatal unit, infundibulum, infraorbital canal, inflammatory disease, fine osseous lamellae and presence of amalgam or step artefacts. Two test phantoms were scanned for both techniques and lens dose was measured. Statistical significant differences in the diagnostic quality of the representation of the fine osseous structures in the paranasal sinuses, attributable to step artefacts were found in the coronally reconstructed images (p < 0.001). However, there was no amalgam and almost no motion artefacts in the reconstructed images. Interobserver correlation was r = 0.953 versus 0.956 for inflammatory disease, r = 0.816 versus 0.852 for artefacts, and r = 0.596 versus 0.547 for fine osseous lamellae in coronally acquired or axially acquired and reconstructed images, respectively. Lens dose was measured between 11.8 mGy and 13.8 mGy for axially acquired and reconstructed images. The advantage of axially acquired, coronally reconstructed images is the absence of artefacts attributable to amalgam and fewer motion artefacts. Axially acquired, coronally reconstructed images are inferior to coronal helical CT images, because of step artefacts, when it comes to evaluating the resolution of fine osseous structures. Nevertheless, reconstructed images are suitable as a investigatory procedure for patients with inflammatory disease who cannot maintain the prone position.

  9. 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.

  10. 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

  11. Socio-economic variation in CT scanning in Northern England, 1990-2002

    Directory of Open Access Journals (Sweden)

    Pearce Mark S

    2012-01-01

    Full Text Available Abstract Background Socio-economic status is known to influence health throughout life. In childhood, studies have shown increased injury rates in more deprived settings. Socio-economic status may therefore be related to rates of certain medical procedures, such as computed tomography (CT scans. This study aimed to assess socio-economic variation among young people having CT scans in Northern England between 1990 and 2002 inclusive. Methods Electronic data were obtained from Radiology Information Systems of all nine National Health Service hospital Trusts in the region. CT scan data, including sex, date of scan, age at scan, number and type of scans were assessed in relation to quintiles of Townsend deprivation scores, obtained from linkage of postcodes with census data, using χ2 tests and Spearman rank correlations. Results During the study period, 39,676 scans were recorded on 21,089 patients, with 38,007 scans and 19,485 patients (11344 male and 8132 female linkable to Townsend scores. The overall distributions of both scans and patients by quintile of Townsend deprivation scores were significantly different to the distributions of Townsend scores from the census wards included in the study (p Conclusions Social inequalities exist in the numbers of young people undergoing CT scans with those from deprived areas more likely to do so. This may reflect the rates of injuries in these individuals and implies that certain groups within the population may receive higher radiation doses than others due to medical procedures.

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

    International Nuclear Information System (INIS)

    Yin, Zhye; De Man, Bruno; Yao, Yangyang; Wu, Mingye; Montillo, Albert; Edic, Peter M.; Kalra, Mannudeep

    2015-01-01

    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

  13. CT Scan Findings of Probable Usual Interstitial Pneumonitis Have a High Predictive Value for Histologic Usual Interstitial Pneumonitis

    Science.gov (United States)

    Chawla, Ashish; Peljto, Anna L.; Cool, Carlyne D.; Groshong, Steve D.; Talbert, Janet L.; McKean, David F.; Brown, Kevin K.; Fingerlin, Tasha E.; Schwarz, Marvin I.; Schwartz, David A.; Lynch, David A.

    2015-01-01

    BACKGROUND: The current usual interstitial pneumonitis (UIP)/idiopathic pulmonary fibrosis CT scan classification system excludes probable UIP as a diagnostic category. We sought to determine the predictive effect of probable UIP on CT scan on histology and the effect of the promoter polymorphism in MUC5B (rs35705950) on histologic and CT scan UIP diagnosis. METHODS: The cohort included 201 subjects with pulmonary fibrosis who had lung tissue samples obtained within 1 year of chest CT scan. UIP diagnosis on CT scan was categorized as inconsistent with, indeterminate, probable, or definite UIP by two to three pulmonary radiologists. Tissue slides were scored by two expert pulmonary pathologists. All subjects with available DNA (N = 200) were genotyped for rs35705950. RESULTS: The proportion of CT scan diagnoses were as follows: inconsistent with (69 of 201, 34.3%), indeterminate (72 of 201, 35.8%), probable (34 of 201, 16.9%), and definite (26 of 201, 12.9%) UIP. Subjects with probable UIP on CT scan were more likely to have histologic probable/definite UIP than subjects with indeterminate UIP on CT scan (82.4% [28 of 34] vs 54.2% [39 of 72]; P = .01). CT scan and microscopic honeycombing were not associated with each other (P = .76). The minor (T) allele of the MUC5B polymorphism was associated with concordant CT scan and histologic UIP diagnosis (P = .03). CONCLUSIONS: Probable UIP on CT scan is associated with a higher rate of histologic UIP than indeterminate UIP on CT scan suggesting that they are distinct groups and should not be combined into a single CT scan category as currently recommended by guidelines. CT scan and microscopic honeycombing may be dissimilar entities. The T allele at rs35705950 predicts a UIP diagnosis by both chest CT scan and histology. PMID:25317858

  14. 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

  15. 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...

  16. 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...

  17. Role of computed tomography (CT scan in staging of cervical carcinoma

    Directory of Open Access Journals (Sweden)

    T V Prasad

    2014-01-01

    Full Text Available Background & objectives: Staging of cervical carcinoma is done clinically using International Federation of Obstetrics and Gynecology (FIGO guidelines. It is based on physical examination findings and also includes results of biopsy, endoscopy and conventional radiological tests like chest radiograph, intravenous urography and barium enema. These conventional radiological investigations have largely been replaced by computed tomography (CT and magnetic resonance imaging (MRI at present. FIGO staging system does not consider CT and MRI mandatory; however, use of these modalities are encouraged. This prospective study was conducted to determine the role of CT in staging work up in women diagnosed with cervical carcinoma. Methods: Fifty three women diagnosed with cervical carcinoma were evaluated with contrast enhanced CT scan of abdomen and pelvis. CT scan images were especially evaluated to determine tumour size, invasion of parmetrium, pelvic walls, rectum, urinary bladder and ureters, pelvic or retroperitoneal lymphadenopathy and distant metastases. CT findings were associated with clinical findings and staging, including findings from cystoscopy and sigmoidoscopy. Results: There was a poor agreement between clinical and CT staging of cervical carcinoma. Primary tumour was demonstrated on CT in 36 (70% of 53 patients. CT underestimated the parametrial, vaginal and pelvic wall invasion when compared with physical examination. CT overestimated the urinary bladder and rectal invasion when compared with cysto-sigmoidoscopy, however, CT had 100 per cent negative predictive value (NPV to exclude bladder and rectal involvement. CT detection of lymph node enlargement and lung metastases influenced the management. Interpretation & conclusions: Our findings show that CT scan does not reliably correlate with clinical FIGO staging of cervical cancer. However, it can detect urinary obstruction as well as nodal or distant metastases and thus improves the

  18. CT scan abnormalities in a series of patients with hemorrhagic shock and encephalopathy syndrome

    International Nuclear Information System (INIS)

    Jardine, D.S.; Winters, W.D.; Shaw, D.W.W.

    1997-01-01

    Background. Hemorrhagic shock and encephalopathy syndrome (HSES) affects children under 1 year of age and is characterized by seizures, shock and certain laboratory abnormalities, including coagulation abnormalities. It has a high mortality and many of the survivors are neurologically abnormal. Objective. To describe abnormalities observed on initial and follow-up CT scans in a group of patients suffering from HSES. Materials and methods. Retrospective review of records and CT scans of ten patients with HSES who were admitted to the intensive care unit of the Children's Hospital and Medical Center, Seattle. Results. Cerebral edema was seen in all cases when the CT scan was obtained between 1 and 7 days after onset of HSES. The basal ganglia and cerebellum were relatively spared, and no hemorrhage was seen. Patients with moderate or marked cerebral edema usually had a poor prognosis. All survivors had significant neurologic sequelae. CT scans obtained after 7 days often showed encephalomalacia with ex vacuo ventricular enlargement. CT scans obtained between 24 h and 4 days after onset will show the acute changes of HSES. CT scans during the initial and convalescent stages of HSES can provide useful information about cerebral edema and encephalomalacia, which occur frequently with this illness. (orig.). With 4 figs., 2 tabs

  19. Brain CT scan in acute carbon monoxide poisoning

    International Nuclear Information System (INIS)

    We, En-Huei

    1986-01-01

    The brain CT findings in 19 patients with acute carbon monoxide poisoning was analysed and the emphasis was placed on the relationship between CT findings and prognosis. Five had a normal manifestation in CT ; eight had the findings of ovoid or patchy low density area in globus pallidus, bilateral or unlateral, during the second day to fifth week after poisoning, and the low density areas were decreasing and blurring in edge in follow up and at last disappeared during 3 - 14 weeks in three cases of them ; nine showed the appearance of diffuse low density of white matter and of globus pallidus in some of them ; two had an appearance of brain atrophy. The pathology of CT findings mentioned above may be brain edema, necrosis, malacia and degeneration in gray matter and globus pallidus. The result suggested the cases with normal CT manifestation, cerebral edema and decreasing and disappearing low density area had a good prognosis, in contrary, the cases with persistant low density in globus pallidus had a poorer prognosis. (author)

  20. 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.

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

    International Nuclear Information System (INIS)

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

    1989-01-01

    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 [fr

  2. Multi-institutional collaborating study on CT scan of schizophrenia

    International Nuclear Information System (INIS)

    Takahashi, Ryo; Sato, Tokijiro; Okuma, Teruo

    1984-01-01

    More abnormal CT findings were observed in nuclear schizophrenic patients (55%) than in the matchable controls with a statistically significant difference. According to the site of the brain, these were marked in the whole ventricle (especially the third ventricle) and in the cortex including the longitudinal fissure, frontal lobe, temporal lobe, and sylvian fissure (especially of the left hemisphere). There was no correlation between the cerebral ventricular enlargement and the patient's age, the duration of illness or drug dosage, suggesting that the enlargement may exist from the onset of the disease. Aging or taking drug(s) were also not responsible for the cortical atrophy. CT findings were associated mainly with negative symptoms. In particular, the association between abnormalities of the left hemisphere and psychiatric symptoms was marked. Direct measurements of CT images revealed significantly higher incidences only in the third ventricular enlargement in schizophrenic patients. These results suggest the possibility that subtypes of schizophrenia can be classified. (Namekawa, K.)

  3. Correlation between image quality of CT scan and amount of intravenous contrast media

    International Nuclear Information System (INIS)

    Yoon, Dae Young; Choi, Dae Seob; Kim, Seung Hyup; Han, Joon Koo; Choi, Byung Ihn; Im, Jung Gi; Han, Moon Hee; Chang, Kee Hyun; Kim, Jong Hyo; Han, Man Chung

    1993-01-01

    A blind, comparative clinical study was performed prospectively to examine the correlation between image quality of CT scan in terms of contrast enhancement effect and amount of intravenous contrast media. A total of 357 patients were randomized into two groups. Ionic high-osmolality contrast media (68% meglumine ioglicate) was administered intravenously as 100 ml bolus in one group and as 50 ml bolus in the other group. Statistically significant differences of image quality were found in CT scans of the brain, head and neck, chest and abdomen (p 0.05). We suggest that amount of contrast media may be reduced in pelvis CT without significant degradation of image quality

  4. Assessment of pancreatic adenocarcinoma: use of low-dose whole pancreatic CT perfusion and individualized dual-energy CT scanning

    International Nuclear Information System (INIS)

    Li, Hai-ou; Guo, Jun; Li, Xiao; Qi, Yao-dong; Wang, Xi-ming; Xu, Zhuo-dong; Liu, Cheng; Chen, Jiu-hong

    2015-01-01

    The objective of this study was to investigate the value of low-dose whole pancreatic computed tomography (CT) perfusion integrated with individualized dual-energy CT (DECT) scanning in the diagnosis of pancreatic adenocarcinoma. Twenty patients with pancreatic adenocarcinoma underwent pancreatic CT perfusion as well as individualized dual-phase DECT pancreatic scans. Perfusion characteristics of non-tumourous pancreatic parenchyma and pancreatic adenocarcinoma were analysed. Weighted-average 120 kVp images and the optimal monoenergetic images in dual phase were reconstructed and the contrast noise ratio (CNR) of pancreas-to-tumour were compared. There were significant difference on blood flow as well as blood volume between pancreatic adenocarcinoma and the non-tumourous pancreatic parenchyma (P < 0.05), whereas no difference on permeability (P > 0.05). CNRs of pancreas-to-tumour in individualized pancreatic phase were significantly higher than those in venous phase (P < 0.05), and CNRs of optimal monoenergetic images were higher than those on weighted-average 120 kVp images (P < 0.05) in both phase. Total effective radiation dose of CT examination was around 9.32–13.75 mSv. Low-dose whole pancreatic CT perfusion can provide functional information, and the individualized pancreatic phase DECT scan is the optimal method for detecting pancreatic adenocarcinomas. The integration of the two techniques has great value in clinical application.

  5. 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...

  6. Exact cone beam CT with a spiral scan

    International Nuclear Information System (INIS)

    Tam, K.C.; Samarasekera, S.; Sauer, F.

    1998-01-01

    A method is developed which makes it possible to scan and reconstruct an object with cone beam x-rays in a spiral scan path with area detectors much shorter than the length of the object. The method is mathematically exact. If only a region of interest of the object is to be imaged, a top circle scan at the top level of the region of interest and a bottom circle scan at the bottom level of the region of interest are added. The height of the detector is required to cover only the distance between adjacent turns in the spiral projected at the detector. To reconstruct the object, the Radon transform for each plane intersecting the object is computed from the totality of the cone beam data. This is achieved by suitably combining the cone beam data taken at different source positions on the scan path; the angular range of the cone beam data required at each source position can be determined easily with a mask which is the spiral scan path projected on the detector from the current source position. The spiral scan algorithm has been successfully validated with simulated cone beam data. (author)

  7. 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.)

  8. Brain tumors and CT scans in infants and children, (4)

    International Nuclear Information System (INIS)

    Oi, Shizuo

    1983-01-01

    We have analyzed the features of individual brain and spinal tumors in infants and children. As to factors affecting prognosis, we have previously reported that the location of a tumor has more distinctive correlations with prognosis than the histological malignancy of a tumor, especially in ependymoma. Based on these results, this study was designed to analyze the CT findings on 9 brain and spinal ependymomas. Seven were seen in the cranium: 5 in the fourth ventricle and 2 in the lateral ventricle. The remaining two were found in the spine: one, in the spinal cord between C 2 and T 10 (spinal level), and the other, in the filum terminale. The ependymomas in the 4th ventricle varied in density on plain CT, peritumoral findings, contast-enhancement pattern, and other observations. At present, it seems to be difficult to distinguish ependymoma from medulloblastoma or 4th ventricular astrocytoma, which tends to have uniform characteristics. However, there are some 4th ventricular ependymomas with a tongue-like projection to the CP angle or cervical canal, the so-called ''plastic ependymoma'' according to Courville and Broussalian. In such a case, ependymoma is strongly suspected on the basis of the CT findings. In the 2 lateral ventricular ependymomas, the relations with the ventricle were rather obscure and the ventricle was collapsed, while all the 4th ventricular ependymomas had hydrocephalus. Our findings contrast with others, reported elsewhere, that lateral ventricular ependymoma advanced into the ventricle and led to prominent ventricular enlargement. Thus, it can be said that ependymoma had a wide variety of supratentorial CT findings as well as contrast-enhancement patterns. Giant tumors growing in the spinal medulla were totally removed because of their clear boundaries with the peripheral regions. A mixed density was frequently seen on CT. (author)

  9. Scanning technology with multi-slice helical CT in security inspection domain

    International Nuclear Information System (INIS)

    Wang Jue; Wang Fuquan; Jiang Zenghui

    2008-01-01

    The paper analyzes the technology conditions of security inspection in home and abroad, and expatiates technology of spiral CT and how to define CT value etc, with studying on the key technology of spiral CT scanning way (X-RAY, detector, technology of pulley etc) and mutual relation. By comparing the present products of security inspection, the conclusion was drawn that it is inevitable to develop the tendency of security inspection area with the checking and discerning the substance by using the technology of multi-layer spiral CT. (authors)

  10. 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.

  11. The value of spiral CT scan on fracture of ankle joint and tarsal bones

    International Nuclear Information System (INIS)

    Li Zhaoli; Liang Jingyin; Pan Zhifeng

    2009-01-01

    Objective: To study the value of spiral CT scan on the fracture of ankle joint and tarsal bones. Methods: 43 cases with the fracture of ankle joint and tarsal bones were collected and analyzed. All the cases were examined by plain film radiography and spiral CT thin slice scan. Multi-planar reformation (MPR), surface shaded display (SSD) and other techniques of image post-processing were performed in 35 cases of them. Results: Spiral CT scan could demonstrate more fractures than plain film radiography in 28 cases(65.1%). There are 15 cases (34.9%) which are normal in plain film radiography but abnormal in Spiral CT scan. Spiral CT could demonstrate the different length, width, direction and number of linear low density shadow. SSD and MPR were performed again in the cases with avulsion fracture and fragmental fracture to demonstrate the fracture direction and the shape, size and location of fragments more clearly. Conclusion: Spiral CT thin slice scan with image post-processing techniques can play an important role in fracture of ankle joint and tarsal bones. (authors)

  12. Reducing radiation dose in liver enhanced CT scan by setting mAs according to plain scan noise

    International Nuclear Information System (INIS)

    Yang Shangwen; He Jian; Yang Xianfeng; Zhou Kefeng; Xin Xiaoyan; Hu Anning; Zhu Bin

    2013-01-01

    Objective: To investigate the feasibility of setting mAs in liver enhanced CT scan according to plain scan noise with fixed mA CT scanner, in order to reduce the radiation dose. Methods: One hundred continuous patients underwent liver enhanced CT scan (group A) prospectively. Two hundred and fifty mAs was used in plain and enhanced CT scans. Noises of plain and venous phase CT images were measured, and the image quality was evaluated. The equation between mAs of enhanced scan and noise of plain scan image was derived. Another 100 continuous patients underwent liver enhanced CT scan (group B). Enhanced scan mAs was calculated from noise on plain scan by using the equation above. Noises on venous phase images were measured and the image quality was measured. Based on body mass index (BMI), patients in groups A and B were divided into three subgroups respectively: BMI < 18.5 kg/m 2 , 18.5 kg/m 2 ≤ BMI < 25.0 kg/m 2 and BMI ≥ 25.0 kg/m 2 . Image quality score was compared with nonparametric rank sum test, CT dose index (CTDI) and effective dose (ED) were measured and compared between each subgroup with 2 independent samples t or t' test. Results: The equation between enhanced scan mAs (mAsX) and plain scan noise (SDp) was as follows: mAsX = mAs1 × [(0.989 × SDp + 1.06) /SDx] 2 , mAs1 = 250 mAs, SDx = 13. In patients with BMI < 18.5 kg/m 2 , ED of group A [(6.86 ± 0.38) mSv, n = 12] was significantly higher than group B [(2.66 ± 0.46) mSv, n = 10)] (t = 18.52, P < 0.01). In patients with 18.5 kg/m 2 ≤ BMI < 25.0 kg/m 2 , ED of group A [(7.08 ± 0.91) mSv, n = 66] was significantly higher than group B [(4.50 ± 1.41) mSv, n = 73] (t' = 10.57, P < 0.01). In patients with BMI ≥ 25.0 kg/m 2 , there was no significant difference between EDs of group A (7.54 ± 0.62 mSv, n = 22) and group B [(8.19 ± 3.16) mSv, n = 17] (t' = 0.89, P = 0.39). Image quality of 5 patients in group A and none in group B did not meet the diagnostic requirement

  13. Medicare Policy Initiatives and the Relative Utilization of "Double-Scan" CT.

    Science.gov (United States)

    Flug, Jonathan A; Hemingway, Jennifer; Hughes, Danny; Silva, Ezequiel; Duszak, Richard

    2016-02-01

    Commonly called "double scans" by the media, combined pre- and postcontrast thoracic and abdominal CT examinations have been the focus of recent CMS policy initiatives. The aim of this study was to examine trends in the relative utilization of double-scan CT before and after 2006 legislation mandating relevant Medicare reporting initiatives. Medicare Physician Supplier Procedure Summary Master Files from 2001 through 2012 were used to identify claims for thoracic and abdominal CT examinations. Double-scan rates by billing physician specialty and place of service were analyzed over time. Rates of double-scan CT between radiologists and nonradiologists were compared using t tests. From 2001 to 2006, double-scan rates for thoracic and abdominal CT examinations declined by 1.7% and 7.5% for radiologists, respectively (from 6.0% to 5.9% and from 22.6% to 20.9%) but increased by 15.8% and 23.6% for nonradiologists (from 5.7% to 6.6% and from 28.8% to 35.6%). From 2006 through 2012, double-scan rates declined by 42.3% and 35.2% (from 5.9% to 3.4% and from 20.9% to 13.5%) for radiologists but only by 31.8% and 8.1% (from 6.6% to 4.5% and from 35.6% to 32.7%) for nonradiologists. Double-scan rates were significantly lower for radiologists than nonradiologists for all years for abdominal CT (P scan rates followed legislation mandating CMS initiatives designed to reduce costs and radiation. For nonradiologists, double-scan rates were consistently higher and declined more slowly than those for radiologists. Medicare policy initiatives directed toward imaging utilization seem to influence behavior differently for radiologists compared with nonradiologists. Copyright © 2016 American College of Radiology. Published by Elsevier Inc. All rights reserved.

  14. The evolution of a brain abscess the complementary roles of radionuclide (RN) and computed tomography (CT) scans

    International Nuclear Information System (INIS)

    Masucci, E.F.; Sauerbrunn, B.J.

    1982-01-01

    Serial /sup 99m/Tc glucoheptonate brain scans demonstrated a brain abscess in a patient from the earliest phase of acute focal encephalitis (cerebritis) through the capsule formation and the recovery phase. The role of the RN and CT scans in the diagnosis of the early stage of cerebritis and the complementary nature of RN and CT scans in intracranial infections, particularly abscesses, are discussed. Guidelines for the use of RN and CT scans are suggested

  15. CT scans in young people in Northern England: trends and patterns 1993-2002

    Energy Technology Data Exchange (ETDEWEB)

    Pearce, Mark S.; Salotti, Jane A.; Metcalf, Wenhua [Newcastle University, Sir James Spence Institute, Royal Victoria Infirmary, Institute of Health and Society, Newcastle upon Tyne (United Kingdom); McHugh, Kieran [Great Ormond Street Hospital for Children NHS Trust, London (United Kingdom); Kim, Kwang P. [Kyung Hee University, Department of Nuclear Engineering, Gyeongi-Do (Korea, Republic of); Craft, Alan W. [Newcastle University, Northern Institute of Cancer Research, Sir James Spence Institute, Royal Victoria Infirmary, Newcastle upon Tyne (United Kingdom); Parker, Louise [Dalhousie University and Cancer Care Nova Scotia, Departments of Medicine and Paediatrics, Population Cancer Research Program, Halifax, NS (Canada); Ron, Elaine [National Cancer Institute, Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics, Bethesda, MD (United States)

    2011-07-15

    Although CT can be greatly beneficial, its relatively high radiation doses have caused public health concerns. To assess patterns in CT usage among patients aged less than 22 years in Northern England during the period 1993-2002. Electronic data were obtained from radiology information systems of all nine National Health Service trusts in the region. A total of 38,681 scans had been performed in 20,483 patients aged less than 22 years. The number of CT examinations rose, with the steepest increase between 1997 and 2000. The number of patients scanned per year increased less dramatically, with 2.24/1,000 population aged less than 22 years having one scan or more in 1993 compared to 3.54/1,000 in 2002. This reflects an increase in the median number of scans per patient, which rose from 1 in 1993 to 2 by 1999. More than 70% of CT examinations were of the head, with the number of head examinations varying with time and patient age. The frequency of CT scans in this population more than doubled during the study period. This is partly, but not wholly, explained by an increase in the number of scans per patient. (orig.)

  16. 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

  17. 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

  18. Application of offset-CT scanning to the inspection of high power feeder lines and connections

    Science.gov (United States)

    Schneberk, Daniel; Maziuk, Robert; Soyfer, Boris; Shashishekhar, N.; Alreja, Rahul

    2016-02-01

    VJT is developing techniques and scanning methods for the in-situ Radiographic and Computed Tomographic inspection of underground high-power feeder cables. The goals for the inspection are to measure the 3D state of the cables and the cable-connections. Recent in-situ Digital Radiographic inspections performed by VJT have demonstrated the value of NDE inspection information for buried power lines. These NDE data have raised further questions as to the exact state of the cables and connections and pointed to the need for more 3D information of the type provided by volumetric CT scanning. VJT is pursuing a three phased approach to address the many issues involved in this type of inspection: 1) develop a high-power feeder-cable test-bed CT scanner, 2) acquire scans on underground feeder pipes that have been removed from service, and 3) from the work in 1) and 2) develop limited-angle CT scanning methods for extending in-situ Digital Radiography to volumetric CT measurements. To this end, VJT has developed and fielded a high-energy test-bed Gantry-type CT scanner (the source and detector move around the object) with a number of important properties. First, the geometry of the gantry-scans can be configured to match the techniques used in the in-situ radiographic inspection. The same X-ray source is employed as in portable Radiographic inspections, a 7.5 MeV Betatron coupled to a Perkin-Elmer Amorphous Silicon detector. Offset-CT scanning is employed as the high-power feeder line assembly is larger than the detector. A description of this scanner and the scan geometry will be presented showing the connection to in-situ radiography. Results from the CT scans of high-power feeder-cable specimens removed from service will be presented with a focus on the inspection potential of volumetric CT data on these assemblies. An evaluation of the scan performance properties of these data compared to the spectrum of life-cycle inspection issues will be presented. Continuing and

  19. Clinical significance of pretreatment FDG PET/CT IN MOBG-avid pediatric neuroblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Seo Young; Kim, Yong Il; Cheon, Gi Jeong; Kang, Keon Wook; Chung, June Key; Lee, Dong Soo; Kang, Hyoung Jin; Shin, Hee Young [Seoul National University Hospital, Seoul (Korea, Republic of); Kim, E. Edmund [Seoul National University, Seoul (Korea, Republic of); Rahim, Muhammad Kashif [Nishtar Medical College and Hospital, Multan (Pakistan)

    2017-06-15

    {sup 18}F-fluorodeoxyglucose-positron emission tomography (FDG-PET) imaging is well known to have clinical significance in the initial staging and response evaluation of the many kinds of neoplasms. However, its role in the pediatric neuroblastoma is not clearly defined. In the present study, the clinical significance of FDG-PET/computed tomography (CT) in 123I- or 131I-metaiodobenzylguanidine (MIBG)-avid pediatric neuroblastoma was investigated. Twenty patients with neuroblastoma who undertook pretreatment FDG PET/CT at our institute between 2008 and 2015 and showed MIBG avidity were retrospectively enrolled in the present study. Clinical information—including histopathology, and serum markers—and several PET parameters—including SUVmax of the primary lesion (Psuv), target-to-background ratio (TBR), metabolic tumor volume (MTV), and coefficient of variation (CV)—were analyzed. The prognostic effect of PET parameters was evaluated in terms of progression-free survival (PFS). Total 20 patients (4.5 ± 3.5 years) were divided as two groups by disease progression. Six patients (30.0 %) experienced disease progression and one patient (5.0 %) died during follow-up period. There were not statistically significant in age, stage, MYCN status, primary tumor size, serum lactate dehydrogenase (LDH), neuron-specific enolase (NSE), and ferritin level between two groups with progression or no progression. However, Psuv (p = 0.017), TBR (p = 0.09), MTV (p = 0.02), and CV (p = 0.036) showed significant differences between two groups. In univariate analysis, PFS was significantly associated with Psuv (p = 0.021) and TBR (p = 0.023). FDG-PET parameters were significantly related with progression of neuroblastoma. FDG-PET/CT may have the potential as a valuable modality for evaluating prognosis in the patients with MIBG-avid pediatric neuroblastoma.

  20. Reduction in radiation doses from paediatric CT scans in Great Britain

    Science.gov (United States)

    Pearce, Mark S; Salotti, Jane A; Harbron, Richard W; Little, Mark P; McHugh, Kieran; Chapple, Claire-Louise; Berrington de Gonzalez, Amy

    2016-01-01

    Objective: Although CT scans provide great medical benefits, concerns have been raised about the magnitude of possible associated cancer risk, particularly in children who are more sensitive to radiation than adults. Unnecessary high doses during CT examinations can also be delivered to children, if the scan parameters are not adjusted for patient age and size. We conducted the first survey to directly assess the trends in CT scan parameters and doses for paediatric CT scans performed in Great Britain between 1978 and 2008. Methods: We retrieved 1073 CT film sets from 36 hospitals. The patients were 0–19 years old, and CT scans were conducted between 1978 and 2008. We extracted scan parameters from each film including tube current–time product [milliampere seconds (mAs)], tube potential [peak kilovoltage (kVp)] and manufacturer and model of the CT scanner. We estimated the mean mAs for head and trunk (chest and abdomen/pelvis) scans, according to patient age (0–4, 5–9, 10–14 and 15–19 years) and scan year (CT dose index and estimated organ doses. Results: For head CT scans, mean mAs decreased by about 47% on average from before 1990 to after 2000, with the decrease starting around 1990. The mean mAs for head CTs did not vary with age before 1990, whereas slightly lower mAs values were used for younger patients after 1990. Similar declines in mAs were observed for trunk CTs: a 46% decline on an average from before 1990 to after 2000. Although mean mAs for trunk CTs did not vary with age before 1990, the value varied markedly by age, from 63 mAs for age 0–4 years compared with 315 mAs for those aged >15 years after 2000. No material changes in kVp were found. Estimated brain-absorbed dose from head CT scans decreased from 62 mGy before 1990 to approximately 30 mGy after 2000. For chest CT scans, the lung dose to children aged 0–4 years decreased from 28 mGy before 1990 to 4 mGy after 2000. Conclusion: We found that mAs for head and trunk

  1. CT scan findings and EEG in systemic lupus erythematodes patients with neuro-psychiatric disorders

    International Nuclear Information System (INIS)

    Kan, Rumiko; Hagiwara, Mariko; Katayose, Keiko; Yashima, Yuko; Kumashiro, Hisashi

    1988-01-01

    In 14 patients with systemic lupus erythematodes presenting with neuro-psychiatric disorders, CT scans were compared with encephalographic (EEG) findings. CT findings were markedly abnormal in 6, slight with a sulcal enlargement in 3, and normal in 5. In the group of markedly abnormal CT findings, focal abnormal low density areas were detected in 2, severe generalized cerebral atrophy in one, and severe atrophy of the right hemisphere in one. EEG findings included focal paroxysmal abnormality of high voltage slow burst at the left frontal dominance and positive spike on the right hemisphere. Epileptic seizure and depressed sensorium seemed to be related to CT abnormality. In 3 patients with epileptic seizures, their symptoms were closely related to CT abnormality. Parkinsonisms and depressed sensorium were also related to CT abnormality. (Namekawa, K)

  2. Relationship to reducing sugar production and scanning electron microscope structure to pretreated hemp hurd biomass (Cannabis sativa)

    International Nuclear Information System (INIS)

    Abraham, Reinu E.; Barrow, Colin J.; Puri, Munish

    2013-01-01

    Lignocellulosic biomass is a highly rigid and recalcitrant structure which requires pretreatment to loosen chemical bonds to make accessible monomeric sugars for biofuel production. In this study, locally available biomass, that is hemp (Cannabis sativa), a low cost feedstock for ethanol production, has been used for the production of fermentable sugars. Hemp hurd biomass (HHB) was exposed to five different pretreatments which included dilute acid (H 2 SO 4 ), alkaline (NaOH), alkaline peroxide, hot water and one stage dilute acid (H 2 SO 4 ). Different pretreatments resulted in loosening and degradation of HHB structure thus facilitating enzymatic saccharification at optimized parameters (pH–4.8 and 50 °C). The changes in the reactive groups (hydroxyl or acetyl) of the HHB were confirmed by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Scanning electron microscopy (SEM) was employed to characterize the surface morphology of untreated and treated HHB. Finally, enzymatic saccharification demonstrated maximum yield of total sugars (743 mg g −1 ) that are suitable for biofuel production. -- Highlights: • Hemp hurd biomass (HHB) was used for producing fermentable sugars. • Alkaline pretreatment resulted in loosening and degradation of hemp structure. • Pretreated HHB was characterized using FTIR studies. • SEM studies evaluated the opening of fiber bundles in pretreatment, thereby increasing cellulose access to enzymes. • Enzymatic saccharification of pretreated HHB demonstrated maximum yield of reducing sugars

  3. Individualized Nonadaptive and Online-Adaptive Intensity-Modulated Radiotherapy Treatment Strategies for Cervical Cancer Patients Based on Pretreatment Acquired Variable Bladder Filling Computed Tomography Scans

    International Nuclear Information System (INIS)

    Bondar, M.L.; Hoogeman, M.S.; Mens, J.W.; Quint, S.; Ahmad, R.; Dhawtal, G.; Heijmen, B.J.

    2012-01-01

    Purpose: To design and evaluate individualized nonadaptive and online-adaptive strategies based on a pretreatment established motion model for the highly deformable target volume in cervical cancer patients. Methods and Materials: For 14 patients, nine to ten variable bladder filling computed tomography (CT) scans were acquired at pretreatment and after 40 Gy. Individualized model-based internal target volumes (mbITVs) accounting for the cervix and uterus motion due to bladder volume changes were generated by using a motion-model constructed from two pretreatment CT scans (full and empty bladder). Two individualized strategies were designed: a nonadaptive strategy, using an mbITV accounting for the full-range of bladder volume changes throughout the treatment; and an online-adaptive strategy, using mbITVs of bladder volume subranges to construct a library of plans. The latter adapts the treatment online by selecting the plan-of-the-day from the library based on the measured bladder volume. The individualized strategies were evaluated by the seven to eight CT scans not used for mbITVs construction, and compared with a population-based approach. Geometric uniform margins around planning cervix–uterus and mbITVs were determined to ensure adequate coverage. For each strategy, the percentage of the cervix–uterus, bladder, and rectum volumes inside the planning target volume (PTV), and the clinical target volume (CTV)-to-PTV volume (volume difference between PTV and CTV) were calculated. Results: The margin for the population-based approach was 38 mm and for the individualized strategies was 7 to 10 mm. Compared with the population-based approach, the individualized nonadaptive strategy decreased the CTV-to-PTV volume by 48% ± 6% and the percentage of bladder and rectum inside the PTV by 5% to 45% and 26% to 74% (p < 0.001), respectively. Replacing the individualized nonadaptive strategy by an online-adaptive, two-plan library further decreased the percentage of

  4. Comparison of absorbed dose of two protocols of tomographic scanning in PET/CT exams

    International Nuclear Information System (INIS)

    Paiva, F.G.

    2017-01-01

    Positron Emission Tomography (PET) associated with Computed Tomography (CT) allows the fusion of functional and anatomical images. When compared to other diagnostic techniques, PET-CT subjects patients to higher levels of radiation, because two modalities are used in a single exam. In this study, the doses absorbed in 19 patient organs from the tomographic scan were evaluated. Radiochromic films were correctly positioned in the Alderson anthropomorphic simulator, male version. For evaluation, two whole body scan protocols were compared. For evaluation, two whole body scan protocols were compared. An increase of up to 600% in the absorbed dose in the pituitary was observed when the protocols were compared, with the lowest observed increase of approximately 160% for the liver. It is concluded that the dose from CT in patients submitted to PET-CT scanning is higher in the protocol used for diagnosis. Considering the high cost of PET-CT exam, in many cases it is preferable that the CT examination is of diagnostic quality, and not only for anatomical mapping, an argument based on the Principle of Justification

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

    Science.gov (United States)

    Michel, Morgane; Jacob, Sophie; Roger, Gilles; Pelosse, Béatrice; Laurier, Dominique; Le Pointe, Hubert Ducou; Bernier, Marie-Odile

    2012-08-01

    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. 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. 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 1.7mSv and 168mGy, respectively. 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. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  6. The value of CT scan in the diagnosis of dural arteriovenous malformations

    International Nuclear Information System (INIS)

    Ikeda, Yukio; Nakazawa, Shozo; Chen, Monan; Murayama, Kyoichi; Yajima, Kouzo

    1984-01-01

    Intracranial arteriovenous malformations (AVM) have been classified into pial, dural, and mixed pial-dural types by means of our angiographic findings. Dural AVM is infrequent and comprises only 10% to 15% of the AVM. Angiography is still the best method to recognize and detect the vascular supply to AVM. There have, however, been few reports on CT findings of dural AVM. In this study we present the CT findings of five cases of dural AVM and try to emphasize the value of CT scan for the diagnosis of dural AVM. The five cases were classified into a hemorrhagic group and a non-hemorrhagic group. In the hemorrhagic group, the CT scan showed an atypical hemorrhagic pattern representing subdural hematoma and intracerebral hematoma. In the non-hemorrhagic group, the CT scan showed a vermiform or patchy enhancement and homogeneous enhancement after the infusion of the contrast medium. The CT scan is useful for the evaluation of associated pathological findings, such as intracerebral hematoma, subdural hematoma, hydrocephalus, and the presence of a mass effect. (author)

  7. Retrospective analyses of super acute cerebral infarction on plain CT scan

    International Nuclear Information System (INIS)

    Mo Changqi; Li Shaolin

    2007-01-01

    Objective: To discuss the diagnostic value of plain CT scan on super acute cerebral infarction. Method 23 patients were retrospective studied, which were confirmed suffering from super acute cerebral infarction. CT scans were performed within 6 hours after onset. TCT-300SCT was used, with slice thickness and distance 10mm. Results 14 patients showed cerebral shape abnormal on CT imaging. Among them, 4 patients showed locally narrowed or disappeared sulci, 8 patients displayed cistern asymmetry of both sides, 2 patients showed lateral ventricle distortion, 5 patients showed slight lower density, 6 cases showed blurry basal nuclei structure. 7 patients showed normal on CT scans. Only 7 patients were diagnosed as super acute cerebral infarction, with the accurate ratio 30.43%. Conclusion: Brain edema and blurry basal nuclei structure are very important features for diagnosing super acute cerebral infarction on plain CT scan, but these features are easily ignored. So we should pay more attention to the CT exhibitions combined with clinical information in order to diagnose correctly and provide useful information for clinical treatment. (authors)

  8. Changes in CT scan following acute embolectomy of the middle cerebral artery

    International Nuclear Information System (INIS)

    Baba, Hiroshi; Ono, Hirohisa; Mori, Kazuo; Kaneko, Mitsuo.

    1982-01-01

    Four cases were presented who developed severe neurological deficits due to the embolic occlusion of the middle cerebral artery but who were successfully treated by embolectomy within 5 to 12 hours after their stroke. The postoperative results were excellent in three cases and good in one. We retrospectively investigated changes in serial CT findings taken pre- and postoperatively in order to examine the effectiveness of this procedure. In three of the cases examined, a preoperative CT scan taken within 6 hours after onset showed noremarkable change attributable to the middle cerebral occlusion. Postoperatively, one case developed a high-density spot in an ischemic low-density area regarded as an hemorrhagic infarction on the CT scan. The serial changes in the CT findings in the other three cases were divided into five stages. On the 5th to 10th postoperative day, moderate mass effects suggesting a brain edema were seen, with transient neurological deterioration; active treatment of these brain edema was quite important to obtain good results. These results suggest that the embolectomy of the middle cerebral artery during actute periods was effective in preventing severe neurological deficits, but was unable to prevent the appearance of a low-density area on the CT scan. A careful observation of the serial CT scans was very useful for making a prognosis and determining adequate postoperative treatment. (J.P.N.)

  9. Changes in CT scan following acute embolectomy of the middle cerebral artery

    Energy Technology Data Exchange (ETDEWEB)

    Baba, Hiroshi; Ono, Hirohisa; Mori, Kazuo (Nagasaki Univ. (Japan). School of Medicine); Kaneko, Mitsuo

    1982-10-01

    Four cases were presented who developed severe neurological deficits due to the embolic occlusion of the middle cerebral artery but who were successfully treated by embolectomy within 5 to 12 hours after their stroke. The postoperative results were excellent in three cases and good in one. We retrospectively investigated changes in serial CT findings taken pre- and postoperatively in order to examine the effectiveness of this procedure. In three of the cases examined, a preoperative CT scan taken within 6 hours after onset showed no remarkable change attributable to the middle cerebral occlusion. Postoperatively, one case developed a high-density spot in an ischemic low-density area regarded as an hemorrhagic infarction on the CT scan. The serial changes in the CT findings in the other three cases were divided into five stages. On the 5th to 10th postoperative day, moderate mass effects suggesting a brain edema were seen, with transient neurological deterioration; active treatment of these brain edema was quite important to obtain good results. These results suggest that the embolectomy of the middle cerebral artery during actute periods was effective in preventing severe neurological deficits, but was unable to prevent the appearance of a low-density area on the CT scan. A careful observation of the serial CT scans was very useful for making a prognosis and determining adequate postoperative treatment.

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

    International Nuclear Information System (INIS)

    Michel, Morgane; Jacob, Sophie; Roger, Gilles; Pelosse, Béatrice; Laurier, Dominique; Le Pointe, Hubert Ducou; Bernier, Marie-Odile

    2012-01-01

    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.

  11. Value of CT scan in the diagnosis of dural arteriovenous malformations

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Yukio; Nakazawa, Shozo; Chen, Monan; Murayama, Kyoichi; Yajima, Kouzo (Nippon Medical School, Tokyo)

    1984-04-01

    Intracranial arteriovenous malformations (AVM) have been classified into pial, dural, and mixed pial-dural types by means of our angiographic findings. Dural AVM is infrequent and comprises only 10% to 15% of the AVM. Angiography is still the best method to recognize and detect the vascular supply to AVM. There have, however, been few reports on CT findings of dural AVM. In this study we present the CT findings of five cases of dural AVM and try to emphasize the value of CT scan for the diagnosis of dural AVM. The five cases were classified into a hemorrhagic group and a non-hemorrhagic group. In the hemorrhagic group, the CT scan showed an atypical hemorrhagic pattern representing subdural hematoma and intracerebral hematoma. In the non-hemorrhagic group, the CT scan showed a vermiform or patchy enhancement and homogeneous enhancement after the infusion of the contrast medium. The CT scan is useful for the evaluation of associated pathological findings, such as intracerebral hematoma, subdural hematoma, hydrocephalus, and the presence of a mass effect.

  12. Brain lesions detected by CT scans in cases of minor head injuries

    International Nuclear Information System (INIS)

    Sekino, Hiroaki; Nakamura, Norio; Yuki, Kenji; Satoh, Jun; Kikuchi, Kunio

    1981-01-01

    Thirty six out of approximately 500 cases which received CT examinations within two weeks after head injury were selected and analyzed. In these cases, almost all high or low density lesions were detected in the tip and/or base of the frontal and/or temporal lobes adjacent to the skull. Causes of the injury were traffic accidents (33.3%), falls on the floor or road (33.3%), and falls down stairs, out of beds, etc. (25.5%). Clinical manifestations before CT examinations were heaviness in the head or headache (36.0%), and nausea and vomiting (33.3%), but thirteen out of 36 patients had no symptoms or complaints. None of the 36 patients showed any neurological dysfunctions suggesting focal damages. Fourteen of the above-mentioned 36 patients (38.9%) had skull fractures and the remaining 22 (61.1%) did not, and there was no significant difference between the two. On the contrary, the incidence of skull fractures in cases in which CT scans were normal was 12.4% which was significantly different from the figure of 38.9% in patients with fractures and CT abnormalities. It is inferred that the deformation of the skull at the time of impact is one of the important factors in the development of brain contusions. To clarify the correlation between the duration of the initial unconsciousness and abnormal CT findings, 219 consecutive cases of head injuries underwent CT scans without considering their severity. Out of 171 patients who were conscious or lost consciousness in less than 10 minutes, 13 (7.6%) had small lesions in CT scans. Of 12 cases with a state of unconsciousness from 10 to 60 minutes in duration, three (25.0%) had abnormal CT findings. In all cases which were unconscious for more than 6 hours, brain lesions were detected by CT scans. (author)

  13. 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.)

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

    International Nuclear Information System (INIS)

    Hoshiko, Sumi; Smith, Daniel; Fan, Cathyn; Jones, Carrie R.; McNeel, Sandra V.; Cohen, Ronald A.

    2014-01-01

    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.)

  15. Pancreas tumor model in rabbit imaged by perfusion CT scans

    Science.gov (United States)

    Gunn, Jason; Tichauer, Kenneth; Moodie, Karen; Kane, Susan; Hoopes, Jack; Stewart, Errol E.; Hadway, Jennifer; Lee, Ting-Yim; Pereira, Stephen P.; Pogue, Brian W.

    2013-03-01

    The goal of this work was to develop and validate a pancreas tumor animal model to investigate the relationship between photodynamic therapy (PDT) effectiveness and photosensitizer drug delivery. More specifically, this work lays the foundation for investigating the utility of dynamic contrast enhanced blood perfusion imaging to be used to inform subsequent PDT. A VX2 carcinoma rabbit cell line was grown in the tail of the pancreas of three New Zealand White rabbits and approximately 3-4 weeks after implantation the rabbits were imaged on a CT scanner using a contrast enhanced perfusion protocol, providing parametric maps of blood flow, blood volume, mean transit time, and vascular permeability surface area product.

  16. Ring-shaped lesions in the CT scan

    International Nuclear Information System (INIS)

    Kazner, E.; Steinhoff, H.; Wende, S.; Mauersberger, W.

    1978-01-01

    Computerised tomography has really opened new dimensions for the diagnosis of various intracranial space-occupying lesions. However, during the last years we had to learn how difficult it can be to evaluate a certain CT finding correctly. Especially the group of ring-type lesions still pose some unsolved problems even if clinical information available in the individual case is considered. The ring blush is a nonspecific finding which occurs in primary and metastatic neoplasms, abscess, infarction, certain stages of intracerebral hematomas and even after neurosurgical operations. The ring blush is caused partly by breakdown of the blood brain barrier, partly by hypervascular pathologic tissue or by both factors. (orig.) [de

  17. 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.

  18. Comparative study of CT scan findings and intellectual function between Parkinson's disease and vascular Parkinsonism

    International Nuclear Information System (INIS)

    Indo, Toshikatsu

    1986-01-01

    Comparative study of CT scan findings and intellectual function between 64 cases with Parkinson's disease and 25 cases with vascular Parkinsonism was carried out. The rate of abnormality of CT scan findings, either ventricular dilatation or widening of sulci, in vascular Parkinsonism was strikingly high compared with Parkinson's disease. Patients could be divided into three groups according to the degree of overall abnormalities of CT scan findings (group A: markedly abnormal, group B: mildly abnormal, group C: normal). Incidences of group A were 9.4 % in Parkinson's disease and 52 % in vascular Parkinsonism, whereas those of group C were 56 % in the former and 28 % in the latter. All patients of group A were over 65 years of age in Parkinson's disease, but one-third of patients in group A were under 59 years of age in vascular Parkinsonism. Moreover, in vascular Parkinsonism, the level of disability was directly proportional to the abnormality of CT scan findings. The rate of predementia and dementia classified by Hasegawa's intelligence scale was 12.5 % in Parkinson's disease and 48 % in vascular Parkinsonism. No difference was found between the mean values of intelligence scale and background factors in Parkinson's disease. On the other hand, the mean value was significantly low in proportion to the poverty of L-dopa effect in vascular Parkinsonism. From these results, the abnormality of CT scan findings and intellectual impairment were probably related to the cerebral pathological process in vascular Parkinsonism, but these relationship was absent in Parkinson's disease. (author)

  19. A case of pineal teratoma with intraventricular free fat on CT scan

    International Nuclear Information System (INIS)

    Uede, Teiji; Takaya, Satoru; Shinya, Toshiyuki; Tanabe, Sumiyoshi; Hashi, Kazuo; Sohma, Tsutomu.

    1986-01-01

    Detection of an intraventricular or intratumoral fat-fluid level on the plain craniograms has been known as a characteristic sign indicating the presence of intracranial teratomatous tumors. On CT scans, however, only thirteen cases have been previously reported to be found an intraventricular and/or subarachnoid free fat associated with spontaneous ruptures of these tumors. We reported a case of pineal teratoma with intraventricular free-fat seen on CT scans. A nine-year-old male with precocious puberty was admitted to our hospital complaining a moderate nonpulsatile headache. Neurological examinations were normal without signs of meningeal irritation. The serum and CSF titer of HCG were raised markedly. The laboratory data of the CSF were normal and there were no pathological cells in the CSF. The CT scans revealed a large heterogeneous mass containing multiple areas of negative density in the pineal region. There were negative density droplets in the bilateral frontal horn on the same CT scans indicating a presence of free fats. At surgery, an yellowish oily material was drained from the tumor, but there was no sign of meningitis over the cortical surface of the occipital lobe. An intraventricular free fat on CT scan have been reported in fourteen cases including ours following the first case described by Fawcitt in 1976. Although most of the cases presented headache, only two cases was diagnosed clinically as chemical meningitis. Pathological changes indicating granulomatous meningitis, however, were noted in five cases, all of them presenting seizure attacks. (author)

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

    International Nuclear Information System (INIS)

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

    2017-01-01

    Highlights: • Repetition of CT in trauma patients occurs relatively often. • Repetition of CT is mainly caused by inadequate image data transfer. • Potentially preventable CT examinations add radiation dose to patients. • Repeated CT is associated with excess costs to the health care system. - Abstract: Objectives: 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. Methods: 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. Results: 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. Conclusion: A considerable number of transferred trauma patients undergo potentially preventable, repeated CT, adding radiation dose to patients and costs to the health care system.

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

    Energy Technology Data Exchange (ETDEWEB)

    Hinzpeter, Ricarda, E-mail: Ricarda.Hinzpeter@usz.ch [Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistr. 100, Zurich CH-8091 (Switzerland); Sprengel, Kai, E-mail: Kai.Sprengel@usz.ch [Division of Trauma Surgery, Department of Surgery, University Hospital Zurich, University of Zurich, Raemistr. 100, CH-8091 Zurich (Switzerland); Wanner, Guido A., E-mail: Guido.Wanner@sbk-vs.de [Division of Trauma Surgery, Department of Surgery, University Hospital Zurich, University of Zurich, Raemistr. 100, CH-8091 Zurich (Switzerland); Department of General Surgery, Schwarzwald-Baar Klinikum, University of Freiburg, Klinikstr. 11, D-78052 Villingen-Schwenningen (Germany); Mildenberger, Peter, E-mail: peter.mildenberger@unimedizin-mainz.de [Department of Diagnostic and Interventional Radiology, University Hospital of Mainz, Langenbeckstr. 1, D-55131 Mainz (Germany); Alkadhi, Hatem, E-mail: hatem.alkadhi@usz.ch [Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Raemistr. 100, Zurich CH-8091 (Switzerland)

    2017-03-15

    Highlights: • Repetition of CT in trauma patients occurs relatively often. • Repetition of CT is mainly caused by inadequate image data transfer. • Potentially preventable CT examinations add radiation dose to patients. • Repeated CT is associated with excess costs to the health care system. - Abstract: Objectives: 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. Methods: 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. Results: 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. Conclusion: A considerable number of transferred trauma patients undergo potentially preventable, repeated CT, adding radiation dose to patients and costs to the health care system.

  2. Characteristic of muscle involvement evaluated by CT scans in early stages of progressive muscular dystrophy

    International Nuclear Information System (INIS)

    Arai, Yumi

    1993-01-01

    Muscle CT scans were performed in order to compare the characteristic distribution of progressive muscle involvement in the early stages of Duchenne type (DMD) and Fukuyama type muscular dystrophy (FCMD). Muscle images at the levels of the 3rd lumbar vertebra, thigh and calf were assessed by visual inspection, and mean CT numbers calculated for individual muscles were statistically analysed. On visual inspection, intramuscular low density areas and muscular atrophy were observed in the muscles of older patients with either disease. These changes were, however, more extensive at thigh level in DMD, and at calf level in FCMD. Nevertheless, the mean CT numbers of muscles in which only slight changes were grossly visible on CT scans displayed progressive decreases with increasing age. Moreover, a significant negative relationship was recognizable between age and mean CT number in almost all muscles examined. Comparison of the slopes of the regression lines revealed that the so-called selective pattern of muscle involvement characteristic of the symptomatic stage had already partially manifested in the preclinical or early stages of both diseases. In FCMD, the rates of decrease in CT numbers were extremely rapid for calf muscles as compared with those in DMD, indicating that this is one reason for FCMD patients never becoming ambulatory. However, for almost all of the other muscles, the CT numbers in FCMD decreased in parallel with the corresponding CT numbers in DMD; thus, these diseases displayed a similarity in the pattern of muscle involvement, despite their different pathogenetic mechanisms and inheritance patterns. (author)

  3. 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.

  4. Standardised tumour, node and metastasis reporting of oncology CT scans

    International Nuclear Information System (INIS)

    Gormly, K. L. M.

    2009-01-01

    Full text: The oncology CT report is a vital piece of communication between the radiologist and the treating clinician and often determines patient management. The use of a standardised report that follows the tumour, node and metastasis (TNM) structure makes it easier for the radiologist to include all of the necessary information in an easy-to-read format. Presenting the results under the headings of primary tumour, lymph nodes, metastases, and other findings follows a similar pattern to that used by pathologists and also follows the thought process of the treating clinician. Standardised templates for TNM-based oncology CT reports were introduced into public and private institutions. An audit of 199 reports demonstrated a significant increase in the presence of measurements and conclusions in the template reports. While there was a non-significant increase in the use of correct Response Evaluation Criteria In Solid Tumours terminology for template reports, there was an improved attempt to describe the disease response. Saving measurements as a summary series on PACS also assists follow-up reporting

  5. Image quality of high-resolution CT with 16-channel multidetector-row CT. Comparison between helical scan and conventional step-shoot scan

    International Nuclear Information System (INIS)

    Sumikawa, Hiromitsu; Johkoh, Takeshi; Koyama, Mitsuhiro

    2005-01-01

    The aim of this study was to evaluate the image quality of high-resolution CT (HRCT) reconstructed from volumetric data with 16-channel multidetector-row CT (MDCT). Eleven autopsy lungs that were diagnosed histopathologically were scanned by 16-channel MDCT with the step-and-shoot scan mode and three helical scan modes. Each helical mode had each size of focal spot, pitch, and time of gantry rotation. HRCT images were reconstructed from the volumetric data with each helical mode and axial sequence data. Two observers evaluated the image quality and noted the most appropriate diagnosis for each imaging. Visualization of abnormal structures with one helical mode was equal to those with axial mode, whereas those with the other two helical modes were inferior to those with axial mode (Wilcoxon signed rank test; p<0.0001). There was no significant difference in diagnostic efficacy between modes. The image quality of HRCT with appropriate helical mode is equal to that with axial mode and diagnostic efficacy is equal among all modes. These results may indicate that sufficient HRCT images can be obtained by only one helical scan without the addition of conventional axial scans. (author)

  6. Hepatic spiral CT in children: scan delay time-enhancement analysis

    International Nuclear Information System (INIS)

    Luker, G.D.; Siegel, M.J.; Bradley, D.A.; Baty, J.D.

    1996-01-01

    Purpose. To compare the effect of different time delays between contrast administration and the start of spiral CT scanning on hepatic enhancement in children. Materials and methods. Forty-five children (2-9 years old, mean 6 years) with no evidence of hepatic disease were examined with spiral CT. Sequential spiral scans through the entire liver were performed following a uniphasic injection of nonionic contrast medium. In group 1 scanning started at 80 % of the contrast injection time, in group 2 scanning started at 100 % of injection time, and in group 3 scanning started at 150 % of injection time. Mean hepatic, aortic, and inferior vena caval enhancement were determined using regions-of-interest measurements. Results. Mean hepatic enhancement was 41.4, 47.0, and 40.6 HU for the 80 %, 100 %, and 150 % injection times, respectively. Enhancement was significantly greater in the 100 % injection time group (p < 0.05). A mean aortocaval difference of greater than 10 HU was present in all examinations. Conclusion. Our results suggest that delaying the initiation of spiral CT scanning until the completion of the contrast injection increases hepatic enhancement in children. These data should help to improve the quality of hepatic spiral CT in pediatric patients. (orig.). With 2 tabs

  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. Algorithm-enabled partial-angular-scan configurations for dual-energy CT.

    Science.gov (United States)

    Chen, Buxin; Zhang, Zheng; Xia, Dan; Sidky, Emil Y; Pan, Xiaochuan

    2018-03-08

    We seek to investigate an optimization-based one-step method for image reconstruction that explicitly compensates for nonlinear spectral response (i.e., the beam-hardening effect) in dual-energy CT, to investigate the feasibility of the one-step method for enabling two dual-energy partial-angular-scan configurations, referred to as the short- and half-scan configurations, on standard CT scanners without involving additional hardware, and to investigate the potential of the short- and half-scan configurations in reducing imaging dose and scan time in a single-kVp-switch full-scan configuration in which two full rotations are made for collection of dual-energy data. We use the one-step method to reconstruct images directly from dual-energy data through solving a nonconvex optimization program that specifies the images to be reconstructed in dual-energy CT. Dual-energy full-scan data are generated from numerical phantoms and collected from physical phantoms with the standard single-kVp-switch full-scan configuration, whereas dual-energy short- and half-scan data are extracted from the corresponding full-scan data. Besides visual inspection and profile-plot comparison, the reconstructed images are analyzed also in quantitative studies based upon tasks of linear-attenuation-coefficient and material-concentration estimation and of material differentiation. Following the performance of a computer-simulation study to verify that the one-step method can reconstruct numerically accurately basis and monochromatic images of numerical phantoms, we reconstruct basis and monochromatic images by using the one-step method from real data of physical phantoms collected with the full-, short-, and half-scan configurations. Subjective inspection based upon visualization and profile-plot comparison reveals that monochromatic images, which are used often in practical applications, reconstructed from the full-, short-, and half-scan data are largely visually comparable except for some

  9. 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.

  10. A case of the CT scanning of a suicidal hanging brain

    International Nuclear Information System (INIS)

    Kawamata, Masaharu; Murooka, Hiroshi; Tanabe, Yasuhiko.

    1988-01-01

    A CT scanning of a case of hanging brain is reported. A 63-year-old man, who had been maintained with Aspirin (30 mg every morning) for cerebral infarction, attempted suicide by hanging, but failed. Several hours later, he was admitted because of consciousness disturbance and so was examined by means of CT scanning. Plain CT scanning showed symmetrical multiple intracerebral hemorrhages. Hemorrhages were found in the subcortical region of the bilateral temporal lobes and in the subependymal region near the foramen of Monro or in the choroidal plexus. We speculated that these hemorrhages may be caused by the congestion of the intracranial venous system caused by squeezing both internal jugular veins by hanging. Past angiograms (1981) for cerebral infarction revealed neither AVM nor angioma. (author)

  11. Feasibility of F-18-FDG PET/CT scan in abdominopelvic regions

    International Nuclear Information System (INIS)

    Suga, Kazuyoshi

    2008-01-01

    F-18-2-Fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET)/CT scan, which simultaneously provides metabolic function and morphology on the same tomographic section, is being the key imaging modality for diagnosis and treatment strategy of makignancies in various organs. FDG PET/CT scanning of the whole body beneficially allows the assessment of primary tumor and regional lymph nodes, and distant metastases and co-existed benign/other malignant lesions, as ''one stop shopping'' fashion. This technique contributes to the selection of the optimal treatment in individual patients, and also can predict histopathologic response to treatment and postoperative/post chemo-radiation therapeutic prognosis. In this paper, we describe the fundamental knowledge required for accurate interpretation of FDG PET/CT scan, and review the utility of this technique for diagnosis and treatment strategy of makignancies in abdominal and pelvic regions. (author)

  12. How to distinguish between bleeding and coagulated extradural hematomas on the plain CT scanning

    International Nuclear Information System (INIS)

    Petersen, O.F.; Espersen, J.O.

    1984-01-01

    Four types of extradural hematoma could be separated at examination of the plain CT scan in 54 extradural hematomas. Two major groups appear: the still bleeding hematoma showing either generally low attenuation values of ''holes'', and a coagulated homogenous type with generally high attenuation values. The attenuation values of the bleeding-liquid part of hematoma - were correlated to hemoglobin concentration in blood, to which clots were not related. Seven extradural hematomas grew and coagulated on repeated preoperative CT scans. In two cases intravenous contrast was given to the bleeding type of hematoma, and the contrast media appeared in ''holes'', but not in areas of high attenuation value. It is easy to distinguish between the different types of hematoma on the plain CT scan, and the separation by eye between the still bleeding and the coagulated extradural hematoma seems reliable. (orig.)

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

    International Nuclear Information System (INIS)

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

    1981-01-01

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

  14. Frequency of primary brain stem lesions after head injuries. A CT scan analysis from 186 cases of severe head trauma

    Energy Technology Data Exchange (ETDEWEB)

    George, B.; Thurel, C.; Pierron, D.; Ragueneau, J.L. (Hopital Lariboisiere, 75 - Paris (France))

    1981-01-01

    Analysis of level of brain stem dysfunction, evolution, and CT scan profile was made on 76 cases of head injuries with prolonged unconsciousness and without hemispheric focal lesion and midline shift on CT scan. Eleven cases were considered normal on CT scan. The CT scan aspect of primary brain stem lesion was identified in 31.5% of these series, and in 14.5% of all severe head traumas (186 cases), from which this series is taken. Primary and secondary CT scan profiles were observed whatever the clinical level of dysfunction and its evolution. Pontine lesions were mainly associated with haemorrhage in the brain stem and diffuse brain swelling; but minimal signs (cortical level) and benign outcome can also be related to axial haemorrhage. These results emphasize the frequency of primary brain stem lesions and the value of CT scan in head injuries.

  15. Importance of serial CT scanning in the diagnosis and treatment of delayed traumatic intracerebral hematoma

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Hidetoshi; Kuwayama, Naoya; Kagawa, Shigeki; Sonobe, Makoto; Takahashi, Shinichiro (Mito National Hospital, Mito (Japan))

    1984-02-01

    Between January, 1980, and December, 1982, 99 cases of traumatic intracranial hemorrhage were admitted to our hospital. Of these cases, we analyzed 25 cases which had been submitted to initial CT scanning within 4 hours after head trauma. We found 17 cases which had no hematoma on the initial CT scan but which were found to have formed intracerebral hematoma on a repeated CT scan. We found that we could classify the delayed traumatic intracerebral hematoma into two types: Type I hematoma, which had a relatively bad outcome, and Type II hematoma which had a relatively good outcome. The neurological sign comes to deteriorate in accordance with the hematoma formation in Type I, while the neurological sign remains unchanged or takes an uphill course in accordance with hematoma formation in Type II. We recognized some differences between the two types both in the time from trauma to hematoma formation and in the serial CT findings. However, we could not differentiate the two types of hematoma on the basis only of the initial CT findings, probably because of a dynamic change in the damaged brain tissue. There seems to be no means to predict the course of delayed traumatic intracerebral hematoma; therefore, we stress the importance of strict observation both of the clinical course and of the serial CT findings in order to diagnose and to choose an appropriate course of therapy, medical or surgical.

  16. The evaluation of CT scan in renal involvement of children with non-Hodgkin's lymphoma

    International Nuclear Information System (INIS)

    Li Yuhua; Shen Jie; Zhu Ming; Tang Jingyan; Xue Huiliang

    2001-01-01

    Objective: To understand the incidence of renal involvement of children with non-Hodgkin's lymphoma and to recognize its different CT findings. Methods: The thoracic and abdominal plain and contrast enhanced CT of 30 cases of NHL in children were reviewed and all cases were confirmed by pathology. The changes in both pre- and post chemotherapy were analysed in the 10 selected cases with renal involvement. Results: CT demonstrated 6 cases of multiple masses and 1 case of multiple patchy lesions in bilateral kidneys. Two cases of single mass and 1 case of multiple masses were detected in single kidney. Conclusion: The incidence of renal involvement of children with non-Hodgkin's lymphoma is relatively high. CT can clearly demonstrate the renal involvement of NHL, which is helpful for clinical stage, especially in the evaluation of the therapeutic effects. Hence, abdominal plain and contrast-enhanced CT scan should be done in children with NHL

  17. Effect of clinical information in brain CT scan interpretation : a blinded double crossover study

    International Nuclear Information System (INIS)

    Zhianpour, M.; Janghorbani, M.

    2004-01-01

    Errors and variations in interpretation can happen in clinical imaging. Few studies have examined the biased effect of clinical information on reporting of brain CT scans. In a blinded double crossover design, we studied whether three radiologists were biased by clinical information when making CT scan diagnosis of the brain. Three consultant radiologists in three rounds with at least a one month interval assessed 100 consecutive cases of brain CT scan. In the first round, clinical information was not available and 100 films without clinical information were given to radiologists. In the second round, the same 100 films were given and true clinical information was available. In the third round, the same 100 films were given and false clinical information was allocated. In 180 cases (60%) the evaluation resulted in the same diagnosis on all three occasions (95% confidence interval (CI): 54.5, 65.5), whereas 120(40%; 95% CI:34.5, 45.5) sets were evaluated differently. 48 cases (16%; 95% CI:11.9,20.1) had discordant evaluation with true and 33 (11%; 95% CI:7.5, 14.5) with false clinical information. Discordance without and with true and false clinical information was 39 (13%; 95% CI:9.2, 16.8). Correct clinical information improves the brain CT report, while the report became less accurate false clinical information was allocated. These results indicate that radiologists are biased by clinical information when reporting brian CT scans

  18. Anatomic Variations of the Paranasal Sinuses on CT Scan Images

    Directory of Open Access Journals (Sweden)

    AR. Talaiepour

    2005-12-01

    Full Text Available Statement of Problem: Variation in paranasal sinus anatomy as shown on computed tomographic scans is of potential significance for it may pose risks during surgery or predispose to certain pathologic conditions.Purpose: The aim of this study was to assess the relative frequency and concurrence of variations in paranasal sinus anatomy in a given population and to compare the results with previous investigations conducted on different populations.Materials and Methods: All patients over 16 years of age referred to Valiasr hospital,Tehran, Iran, with paranasal sinus tomographic scans and a clinical diagnosis of chronic sinusitis were considered for this study. After excluding those with altered anatomy(iatrogenic or pathologic, scans of unaltered patients were meticulously analyzed for variations in sinus anatomy. Findings were recorded on the patient’s data sheet. The distance between the maxillary sinus floor and the alveolar ridge at the level of the 1stmolar was recorded. All findings were analyzed, and tested with Chi square, where applicable.Results: Overall 143 patients were analyzed (48.3% male and 51.7% female. The frequency of major sinus variations was: Agger nasi cell in 56.7%, Haller cell in 3.5%,Onodi cell in 7%, nasal septal deviation in 63%, Concha bullosa in 35%, and dental anomalies in 4.9% of the studied cases. The distance between the upper alveolar ridge and maxillary sinus floor was 0-30mm (mean 12.16 on the right, and 0-52mm (mean 12.20 on the left.Conclusion: The frequency of anatomic variations in sinus anatomy may be related to race and heredity. A lower number of cases in addition to the use of low yield imaging may explain the discrepancies observed between our results and other investigations.The findings of the present study were based on computed tomography.

  19. 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

    Non-invasive estimation of age at death has been carried out by using 3D CT scanning of a bog body discovered in 1948 in a peat bog in Borremose (Denmark). The bog body has been dated to the 8th century BC, in the last part of the Bronze Age. The skeletal structures useful for age estimation have...... 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...

  20. 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...

  1. CT scans of Sts 14 provide the potential for manufacturing casts

    CSIR Research Space (South Africa)

    Kirkbride, AN

    1997-04-01

    Full Text Available 'Web Page, HTML only' file (.html). In Netscape, select FILE then SAVE AS from your browser's toolbar above. Record: 1 Title: CT scans for Sts 14 provide the potential for manufacturing casts. Authors: Yates, Simon C. Kirkbride, Anthony N. Source....ebscohost.com.innopac.up.ac.za:80/login.aspx?direct=true&db=aph&AN=9710054059&site=ehost-live&scope=site Cut and Paste: CT scans for Sts 14 provide...

  2. False Positive Uptake in Bilateral Gynecomastia on 68Ga-PSMA PET/CT Scan.

    Science.gov (United States)

    Sasikumar, Arun; Joy, Ajith; Nair, Bindu P; Pillai, M R A; Madhavan, Jayaprakash

    2017-09-01

    A 66-year-old man on hormonal therapy with prostate cancer was referred for Ga-PSMA PET/CT scan for biochemical recurrence. Ga-PSMA PET/CT scan detected moderate heterogeneous tracer concentration in bilateral breast parenchyma, in addition to the abnormal tracer concentration in enlarged prostate gland, right external iliac lymph node, and sclerotic lesion in L4 vertebra. On clinical examination, he was found to have bilateral gynecomastia. Abnormal concentration of Ga-PSMA in breast cancer is now well known, and in this context, it is important to know that tracer localization can occur in gynecomastia as well, as evidenced in this case.

  3. Subperiosteal chondroma. Diagnostic value of CT scan imaging in two cases

    International Nuclear Information System (INIS)

    Lerais, J.M.; Auquier, F.; Baudrillard, J.C.; Durot, J.F.; Laugareil, P.; Wallays, C.; Lefort, G.; Daoud, S.; Gaillard, D.

    1988-01-01

    Results of CT scan exploration are reported in two cases of subperiosteal chondroma, one in a 4 year old child affecting the anterior tibial tuberosity the other in a 9 year old child involving the upper end of humerus. Data from CT scan imaging were undoubtedly superior to those of conventional radiography and appear to be characteristic of this benign cartilaginous tumor, greatly facilitating correlation between clinical, radiological and pathologic findings. The scanner should allow certain situations to be dedramatized and the surgical attitude adapted when the functional prognosis is involved [fr

  4. Lens exposure during brain scans using multidetector row CT scanners: methods for estimation of lens dose.

    Science.gov (United States)

    Suzuki, S; Furui, S; Ishitake, T; Abe, T; Machida, H; Takei, R; Ibukuro, K; Watanabe, A; Kidouchi, T; Nakano, Y

    2010-05-01

    Some recent studies on radiation lens injuries have indicated much lower dose thresholds than specified by the current radiation protection guidelines. The purpose of this research was to measure the lens dose during brain CT scans with multidetector row CT and to assess methods for estimating the lens dose. With 8 types of multidetector row CT scanners, both axial and helical scans were obtained for the head part of a human-shaped phantom by using normal clinical settings with the orbitomeatal line as the baseline. We measured the doses on both eyelids by using an RPLGD during whole-brain scans including the orbit with the starting point at the level of the inferior orbital rim. To assess the effect of the starting points on the lens doses, we measured the lens doses by using 2 other starting points for scanning (the orbitomeatal line and the superior orbital rim). The CTDIvols and the lens doses during whole-brain CT including the orbit were 50.9-113.3 mGy and 42.6-103.5 mGy, respectively. The ratios of lens dose to CTDIvol were 80.6%-103.4%. The lens doses decreased as the starting points were set more superiorly. The lens doses during scans from the superior orbital rim were 11.8%-20.9% of the doses during the scans from the inferior orbital rim. CTDIvol can be used to estimate the lens dose during whole-brain CT when the orbit is included in the scanning range.

  5. Colon distension and scan protocol for CT-colonography: An overview

    International Nuclear Information System (INIS)

    Boellaard, Thierry N.; Haan, Margriet C. de; Venema, Henk W.; Stoker, Jaap

    2013-01-01

    This article reviews two important aspects of CT-colonography, namely colonic distension and scan parameters. Adequate distension should be obtained to visualize the complete colonic lumen and optimal scan parameters should be used to prevent unnecessary radiation burden. For optimal distension, automatic carbon dioxide insufflation should be performed, preferably via a thin, flexible catheter. Hyoscine butylbromide is – when available – the preferred spasmolytic agent because of the positive effect on insufflation and pain/burden and its low costs. Scans in two positions are required for adequate distension and high polyp sensitivity and decubitus position may be used as an alternative for patients unable to lie in prone position. The great intrinsic contrast between air or tagging and polyps allows the use of low radiation dose. Low-dose protocol without intravenous contrast should be used when extracolonic findings are deemed unimportant. In patients suspected for colorectal cancer, normal abdominal CT scan protocols and intravenous contrast should be used in supine position for the evaluation of extracolonic findings. Dose reduction can be obtained by lowering the tube current and/or voltage. Tube current modulation reduces the radiation dose (except in obese patients), and should be used when available. Iterative reconstructions is a promising dose reducing tool and dual-energy CT is currently evaluated for its applications in CT-colonography. This review also provides our institution's insufflation procedure and scan parameters

  6. Evaluation of a metal artifact reduction algorithm applied to post-interventional flat detector CT in comparison to pre-treatment CT in patients with acute subarachnoid haemorrhage

    International Nuclear Information System (INIS)

    Mennecke, Angelika; Svergun, Stanislav; Doerfler, Arnd; Struffert, Tobias; Scholz, Bernhard; Royalty, Kevin

    2017-01-01

    Metal artefacts can impair accurate diagnosis of haemorrhage using flat detector CT (FD-CT), especially after aneurysm coiling. Within this work we evaluate a prototype metal artefact reduction algorithm by comparison of the artefact-reduced and the non-artefact-reduced FD-CT images to pre-treatment FD-CT and multi-slice CT images. Twenty-five patients with acute aneurysmal subarachnoid haemorrhage (SAH) were selected retrospectively. FD-CT and multi-slice CT before endovascular treatment as well as FD-CT data sets after treatment were available for all patients. The algorithm was applied to post-treatment FD-CT. The effect of the algorithm was evaluated utilizing the pre-post concordance of a modified Fisher score, a subjective image quality assessment, the range of the Hounsfield units within three ROIs, and the pre-post slice-wise Pearson correlation. The pre-post concordance of the modified Fisher score, the subjective image quality, and the pre-post correlation of the ranges of the Hounsfield units were significantly higher for artefact-reduced than for non-artefact-reduced images. Within the metal-affected slices, the pre-post slice-wise Pearson correlation coefficient was higher for artefact-reduced than for non-artefact-reduced images. The overall diagnostic quality of the artefact-reduced images was improved and reached the level of the pre-interventional FD-CT images. The metal-unaffected parts of the image were not modified. (orig.)

  7. Evaluation of a metal artifact reduction algorithm applied to post-interventional flat detector CT in comparison to pre-treatment CT in patients with acute subarachnoid haemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Mennecke, Angelika; Svergun, Stanislav; Doerfler, Arnd; Struffert, Tobias [University of Erlangen-Nuremberg, Department of Neuroradiology, Erlangen (Germany); Scholz, Bernhard [Siemens Healthcare GmbH, Forchheim (Germany); Royalty, Kevin [Siemens Medical Solutions, USA, Inc., Hoffman Estates, IL (United States)

    2017-01-15

    Metal artefacts can impair accurate diagnosis of haemorrhage using flat detector CT (FD-CT), especially after aneurysm coiling. Within this work we evaluate a prototype metal artefact reduction algorithm by comparison of the artefact-reduced and the non-artefact-reduced FD-CT images to pre-treatment FD-CT and multi-slice CT images. Twenty-five patients with acute aneurysmal subarachnoid haemorrhage (SAH) were selected retrospectively. FD-CT and multi-slice CT before endovascular treatment as well as FD-CT data sets after treatment were available for all patients. The algorithm was applied to post-treatment FD-CT. The effect of the algorithm was evaluated utilizing the pre-post concordance of a modified Fisher score, a subjective image quality assessment, the range of the Hounsfield units within three ROIs, and the pre-post slice-wise Pearson correlation. The pre-post concordance of the modified Fisher score, the subjective image quality, and the pre-post correlation of the ranges of the Hounsfield units were significantly higher for artefact-reduced than for non-artefact-reduced images. Within the metal-affected slices, the pre-post slice-wise Pearson correlation coefficient was higher for artefact-reduced than for non-artefact-reduced images. The overall diagnostic quality of the artefact-reduced images was improved and reached the level of the pre-interventional FD-CT images. The metal-unaffected parts of the image were not modified. (orig.)

  8. Radiologic evaluation of orbital index among Ghanaians using CT scan.

    Science.gov (United States)

    Botwe, Benard Ohene; Sule, Derick Seyram; Ismael, Abdul Mumin

    2017-07-11

    Orbital index (OI) expresses the proportion of the orbital height to the orbital width and varies with race, regions within the same race and periods in evolution. This index is useful in forensic medicine, anthropology and surgery. However, the average OI among Ghanaian adults was unknown. The aim of this study was to determine the orbital index of adult Ghanaians and classify them under one of the three predetermined groups. The study design was a retrospective cross-sectional. A systematic random sampling method was used for selecting 350 adult Ghanaian head computed tomography images available from 1 January to 31 December 2015 at KBTH Hospital. The orbital height and orbital width of each orbit were measured on a 3D CT skull. Data was analysed using Microsoft Excel and Statistical Package for Social Sciences version 20. The study had more females than men (167, 47.71%, vs 183, 52.29%). The observed orbital index of Ghanaians in the study was 81.22 ± 4.22. The mean orbital index was 80.52 ± 4.66 in males and 82.15 ± 3.83 in females with their difference being statistically significant (p value forensic medicine for skull classification and also for better surgical approach in neurosurgery as well as cosmetic surgery.

  9. An experimental study on the acute myocardial infarction with CT perfusion scans

    International Nuclear Information System (INIS)

    Liu Yuanjian; Yan Weiqiang; Wang Chenglin; Liu Pengcheng; Feng Xiaoyuan; Shen Tianzhen; Chen Xingrong

    2004-01-01

    Objective: To determine the reliability of CT perfusion scans and its parameters of γ-variate curve in evaluating the acute myocardial infarction for clinical reference of diagnosis on coronary artery disease and myocardial infarction. Methods: Imatron C-150 electron beam CT (EBCT) were used to scan a hydrodynamic model which could mimic a change of contrast medium by intravenous injection in vivo. Then 6 adult canines were employed in the experiment with thoracic operation, and branches of the anterior descending and circumflex of left coronary arteries (LCA) were ligated so that myocardial infarction was made out. After intravenous administration of contrast medium, the hearts were scanned with perfusion EBCT and γ-variate curves were manifested. Some heterogeneities and differentiations between the normality and the infarctions were put forward when the parameters of all these curves were analyzed and statistically processed. Two myocardial infarctions were also verified by SPECT, and all the samples stained with TTC method were compared with those on the perfusion images. The pathological study with optical microscope and electron microscope were further carried on. Results: The ascending slopes of γ-variate curves were different in the perfusion quantity. The normal curve of canine myocardium showed a somewhat quick ascending pattern first, and then a gradual descending pattern successively, with the ascending time of about 10-13 s, ascending CT value of about 34-37 HU, and peak CT value of about 70-81 HU. Whereas the curve on myocardial infarction demonstrated a prolonged ascending time of about 19.9 s, diminished ascending CT value of only about 20 HU, and peak CT value of about 53.8 HU, which were significantly different from the normality (P<0.05). Conclusion: There are some differences in γ-variate curves between normal myocardium and myocardial infarction, which can be detected by CT perfusion scan. (authors)

  10. Isolated LOC in head trauma associated with significant injury on brain CT scan.

    Science.gov (United States)

    Waseem, Muhammad; Iyahen, Patrick; Anderson, Hilary Bryan; Kapoor, Kevin; Kapoor, Ramnath; Leber, Mark

    2017-09-25

    A report of loss of consciousness (LOC) is frequently considered reason enough to obtain a computed tomography (CT) scan in the evaluation of head trauma. We conducted this study to reduce exposure to radiation from CT, while still not overlooking clinically significant injuries. The objective of the study is to determine the correlation between LOC status and brain CT scan results in patients with blunt head trauma and to determine whether there is a subset of patients for whom CT scan need not be performed, without missing clinically significant intracranial injuries. This is a retrospective study conducted in the emergency department of an inner-city hospital. The patient population included patients ranging between 13 and 35 years of age, with blunt head trauma, who presented to the emergency department (ED) between January 2010 and December 2013. Patients were divided into two groups: "LOC" group and "no LOC" group. The results of brain CT scans from each group were compared with LOC status. For study purposes, "clinically significant" were those that required interventions or ICU hospitalization of at least 24 h or extended hospitalization. The results were analyzed using chi-square calculations. During the study period, 494 patients were identified as having suffered head trauma. Of these, 185 (37.5%) reported LOC and 309 (62.5%) did not lose consciousness. In the LOC group, 15 (8.1%) had significant CT findings compared to 1.3% (4/309) of those without LOC (p scan should be obtained in patients with LOC, no physical findings, and a normal GCS after blunt head trauma.

  11. 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.

  12. 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

  13. 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

  14. A three-dimensional graphic reconstruction method of the vertebral column from CT scans

    International Nuclear Information System (INIS)

    Verbout, A.J.; Falke, T.H.M.; Tinkelenberg, J.

    1983-01-01

    The method of graphic reconstruction using the oblique view technique was applied on the transverse CT scans of the vertebral column. In the scanning procedure the low-dose thin-slice technique was used. The method proved valuable for the construction of three-dimensional models as reliable reproduction of the original. The results are useful for preoperative evaluation of the deformed spine as well as for anatomic research. (orig.)

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

    International Nuclear Information System (INIS)

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

    2014-01-01

    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

  16. An Individually Optimized Protocol of Contrast Medium Injection in Enhanced CT Scan for Liver Imaging

    Directory of Open Access Journals (Sweden)

    Shi-Ting Feng

    2017-01-01

    Full Text Available Objective. To investigate the effectiveness of a new individualized contrast medium injection protocol for enhanced liver CT scan. Methods. 324 patients who underwent plain and dual phase enhanced liver CT were randomly assigned to 2 groups: G1 (n=224, individualized contrast medium injection protocol; G2 (n=100, standard contrast medium injection with a dose of 1.5 ml/kg. CT values and ΔHU (CT values difference between plain and enhanced CT of liver parenchyma and tumor-liver contrast (TLC during hepatic arterial phase (HAP and portal venous phase (PVP and contrast medium dose were measured. The tumor conspicuity of hepatocellular carcinoma (HCC between two groups was independently evaluated by two radiologists. Results. The mean contrast medium dose of G1 was statistically lower than that of G2. There were no significantly statistical differences in CT values and ΔHU of liver parenchyma during HAP, TLC values during HAP, and PVP between two groups. The CT values and ΔHU of liver parenchyma during PVP of G2 were significantly higher than those of G1. Two independent radiologists were both in substantial conformity in grading tumor conspicuity. Conclusion. Using the individually optimized injection protocol might reduce contrast medium dose without impacting on the imaging quality in enhanced liver CT.

  17. Dose reduction for CT in children with cystic fibrosis: is it feasible to reduce the number of images per scan?

    International Nuclear Information System (INIS)

    Jong, Pim A. de; Tiddens, Harm A.W.M.; Nakano, Yasutaka; Lequin, Maarten H.

    2006-01-01

    Reducing the dose for each CT scan is important for children with cystic fibrosis (CF). To determine whether the number of CT images and therefore the dose per CT scan could be reduced without any significant loss of information in children with CF. A cohort of children with CF was followed with biennial surveillance CT scans, obtained in inspiration after a voluntary breath-hold as 1-mm thick images at 10-mm intervals from lung apex to base. A random set of 20 baseline CT scans and 10 follow-up CT scans were blinded. Sets of every image (10-mm intervals), every second image (20-mm intervals), every third image (30-mm intervals) and a selection of three and five images were scored randomly using a published CT scoring system by one experienced observer. The 20 subjects were 10 years of age with a range of 3.7-17.6 years at baseline. Fewer CT images resulted in a significantly lower (less abnormal) CT score and the number of patients positive for abnormalities decreased subsequently. At intervals greater than 20 mm no significant change in CT score over 2 years could be detected, while the CT scores at 10-mm (P=0.02) and 20-mm (P=0.02) intervals worsened significantly. A reduction in the number of inspiratory CT images by increasing the interval between images to greater than 10 mm is not a valid option for radiation dose reduction in children with CF. (orig.)

  18. Reconstructing 3D x-ray CT images of polymer gel dosimeters using the zero-scan method

    Science.gov (United States)

    Kakakhel, M. B.; Kairn, T.; Kenny, J.; Trapp, J. V.

    2013-06-01

    In this study x-ray CT has been used to produce a 3D image of an irradiated PAGAT gel sample, with noise-reduction achieved using the 'zero-scan' method. The gel was repeatedly CT scanned and a linear fit to the varying Hounsfield unit of each pixel in the 3D volume was evaluated across the repeated scans, allowing a zero-scan extrapolation of the image to be obtained. To minimise heating of the CT scanner's x-ray tube, this study used a large slice thickness (1 cm), to provide image slices across the irradiated region of the gel, and a relatively small number of CT scans (63), to extrapolate the zero-scan image. The resulting set of transverse images shows reduced noise compared to images from the initial CT scan of the gel, without being degraded by the additional radiation dose delivered to the gel during the repeated scanning. The full, 3D image of the gel has a low spatial resolution in the longitudinal direction, due to the selected scan parameters. Nonetheless, important features of the dose distribution are apparent in the 3D x-ray CT scan of the gel. The results of this study demonstrate that the zero-scan extrapolation method can be applied to the reconstruction of multiple x-ray CT slices, to provide useful 2D and 3D images of irradiated dosimetry gels.

  19. Investigation of the potential causes of partial scan artifacts in dynamic CT myocardial perfusion imaging

    Science.gov (United States)

    Tao, Yinghua; Speidel, Michael; Szczykutowicz, Timothy; Chen, Guang-Hong

    2014-03-01

    In recent years, there have been several findings regarding CT number variations (partial scan artifact or PSA) across time in dynamic myocardial perfusion studies with short scan gated reconstruction. These variations are correlated with the view angle range corresponding to the short scan acquisition for a given cardiac phase, which can vary from one cardiac cycle to another due to the asynchrony between heart rate and gantry rotation speed. In this study, we investigate several potential causes of PSA, including noise, beam hardening and scatter, using numerical simulations. In addition, we investigate partial scan artifact in a single source 64-slice diagnostic CT scanner in vivo data sets, and report its effect on perfusion analysis. Results indicated that among all three factors investigated, scatter can cause obvious partial scan artifact in dynamic myocardial perfusion imaging. Further, scatter is a low frequency phenomenon and is not heavily dependent on the changing contrasts, as both the frequency method and the virtual scan method are effective in reducing partial scan artifact. However, PSA does not necessarily lead to different blood volume maps compared to the full scan, because these maps are usually generated with a curve fitting procedure.

  20. 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...

  1. Diffuse cystic peritoneal lymphangiomatosis. Long-term clinical, ultrasonographic and CT scan study in one case

    International Nuclear Information System (INIS)

    Berry, M.; Paillot, B.; Monneins, F.; Delafolie, A.; Guyet-Rousset, P.

    1987-01-01

    An adult male with episodic manifestations of abdominal lymphangiomatosis has been followed up over a 5 year period. This prolonged surveillance of clinical features combined with ultrasound and CT scan imaging has no doubt contributed to improved knowledge of diagnostic and physiopathologic factors of these rare lesions. The particular behavior of the case reported evokes discussion on the conventional surgical treatment of lymphangioma [fr

  2. 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...

  3. Micro-CT scan, electron microscopy and optical microscopy study of insertional traumas of cochlear implants.

    Science.gov (United States)

    Le Breton, Alexia; Jegoux, Franck; Pilet, Paul; Godey, Benoit

    2015-09-01

    Knowledge of cochlear trauma resulting from the implantation of electrodes is important for the development of atraumatic surgical techniques. The purpose of this study was to demonstrate the advantages of micro-CT scanning, back-scattered electron microscopy (BSEM) and optical microscopy (OM) in understanding the mechanisms of cochlear trauma due to cochlear implantation. Our study involved six petrous bones removed from fresh human cadavers: one control specimen plus five other specimens that were surgically implanted with Neurelec Digisonic SP EVO electrode arrays. All six specimens underwent glycol methyl methacrylate embedding, were examined via micro-CT scan and were then sectioned for histological analysis of undecalcified samples via BSEM and OM. The 2D micro-CT scan reconstructions did not display cochlear microtrauma due to a limited resolution and the loss of information caused by the metallic artifacts of the intracochlear electrodes. The 3D reconstructions displayed the quality of the electrode array positioning in the cochlea and enabled determining the axes on which to section the specimens for histological examination. BSEM afforded a clear view of the damage to the osseous structures of the cochlea, but did not display the soft tissue injuries. OM enabled viewing and grading the histological lesions resulting from insertion. In our opinion, the combination of 3D micro-CT scan reconstructions and histological analysis using OM appears to be the best method to analyze this type of trauma.

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

    International Nuclear Information System (INIS)

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

    1986-01-01

    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. (orig.)

  5. Prediction of Clinical Outcome in Acute Hemorrhagic Stroke from a Single CT Scan on Admission.

    Science.gov (United States)

    Nag, Chiranjib; Das, Kamalesh; Ghosh, Mrinalkanti; Khandakar, M R

    2012-10-01

    From a single CT scan in primary intracerebral hemorrhage (ICH), clinical outcome can be assessed on admission by using the CT scan parameters. The study aims to find out how hematoma volume, location of stroke, midline shift, intraventricular extension of bleed and ventricle compression influence the clinical outcome in patients with acute ICH. Non-contrast CT scan was done on admission in hospital for every patient with acute hemorrhagic stroke and was analyzed accordingly. Clinical assessments were done in National Institute of Health Stroke Scale (NIHSS). Chi-square test and multiple logistic regression analysis were used for statistical analysis. Mean hematoma volume associated with death before 30 days is 33.16 cm(3) (P 30 cm(3) (OR = 27.857), brain stem hemorrhage (OR = 6.000), intraventricular extension of bleed from other location (OR = 7.846), presence of ventricular compression alone (OR = 2.700) and in combination with midline shift of ≥ 5 mm (OR = 2.124). From a single CT scan during hospital admission, mortality and morbidity in next 30 days can be predicted. A hematoma volume >30 cm(3), brain stem hematoma, intraventricular extension of bleed and ventricular compression along and with midline shift are associated with early mortality in ICH.

  6. 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.

  7. 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

    Non-invasive estimation of age at death has been carried out by using 3D CT scanning of a bog body discovered in 1948 in a peat bog in Borremose (Denmark). The bog body has been dated to the 8th century BC, in the last part of the Bronze Age. The skeletal structures useful for age estimation have...

  8. Comparison of extensive brain calcification in postoperative hypoparathyroidism on CT and NMR scan

    International Nuclear Information System (INIS)

    Lang, C.; Huk, W.; Pichl, J.

    1989-01-01

    A case of postoperative hypoparathyroidism is presented in which calcifications seen on CT scan were differently visualized on T 2 weighted NMR images. High and low signal intensities may reflect different stages of the calcifying process thus confirming neuropathological findings. (orig.)

  9. Comparison of extensive brain calcification in postoperative hypoparathyroidism on CT and NMR scan

    Energy Technology Data Exchange (ETDEWEB)

    Lang, C.; Huk, W.; Pichl, J.

    1989-03-01

    A case of postoperative hypoparathyroidism is presented in which calcifications seen on CT scan were differently visualized on T/sub 2/ weighted NMR images. High and low signal intensities may reflect different stages of the calcifying process thus confirming neuropathological findings.

  10. 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

  11. Clinical features and CT scan findings of supratentorial ependymomas and ependymoblastomas

    International Nuclear Information System (INIS)

    Hanakita, Junya; Handa, Hajime

    1984-01-01

    The clinical courses and CT scan findings of 12 cases of supratentorial ependymoma and ependymoblastoma were reviewed. The age of the patient of ependymoma ranged from 3 years to 34 years, with an average age of 16 years. The follow-up time ranged from 2 months to 9 years and 10 months. All of the six patients are still alive. The age of the patients of ependymoblastoma ranged from 7 months to 34 years, with an average age of 17 years. During the follow-up period from 2 weeks to 6 years and 4 months, four patients died. Supratentorial ependymomas and ependymoblastomas show the following characteristic features of CT scans: 1. Calcification: The incidence of calcification was 50% in ependymoma-group, and 100% in ependymoblastoma-group. 2. Cyst formation, ring-enhancement: The cyst formation was noticed in both groups. In ependymoma-group a smooth ring-enhancement pattern and the strongly enhanced mural nodule-like contour were found, but in ependymoblastoma-group, the cyst wall was enhanced in irregular shape. 3. Perifocal edema and mass effect: Considerable mass effect was noticed in both groups. Perifocal edema was slight in many cases of ependymoma-group, but mostly prominent in ependymoblastoma-group. 4. CT scan findings of recurrent tumor: In ependymoma-group, recurrent tumor showed the same characteristics of CT scan as the initial ones. In ependymoblastoma-group, cystic portion decreased in size and irregular shaped solid portion increased in recurrence. (author)

  12. Value of CT scanning in radiation therapy treatment planning: a prospective study

    International Nuclear Information System (INIS)

    Goitein, M.; Wittenberg, J.; Mendiondo, M.; Doucette, J.; Friedberg, C.; Ferrucci, J.; Gunderson, L.; Linggood, R.; Shipley, W.U.; Fineberg, H.V.

    1979-01-01

    We report the results of a prospective study in which we assessed the value of computed tomography (CT) scanning in planning radiation therapy for 77 patients. First, conventional studies were performed, treatment fields were designed and simulated and, where appropriate, computer generated treatment plans drawn up. Then a CT scan was performed to delineate the location of the tumor and adjacent uninvolved tissues. The treatment goals and plans were reevaluated and changed when necessary. Forty of the 77 patients (52%) had their treatment changed as a result of the CT scan. Of these, four (5%) had a change of treatment modality. Thirty-two patients (42%) had changes in the radiotherapy technique because of inadequate tumor coverage (in 24 patients (31%) part of the tumor was outside one or more of the fields and in the other 8 patients (10%) the tumor coverage was marginal). Field changes resulting only from considerations of normal tissue coverage were made for 4 of these patients (5%). In total, normal tissue coverage was affected in 36 patients (47%). When the significance of these changes was evaluated, CT scanning was judged to be of major value for 28 of the 77 patients (36%) and of minor value in a further 12 patients

  13. Study Finds Small Increase in Cancer Risk after Childhood CT Scans

    Science.gov (United States)

    A study published in the June 6, 2012, issue of The Lancet shows that radiation exposure from computed tomography (CT) scans in childhood results in very small but increased risks of leukemia and brain tumors in the first decade after exposure.

  14. Original Article Utility of CT Scan and CA 19-9 in Predicting Non ...

    African Journals Online (AJOL)

    KIGZ

    Utility of CT Scan and CA 19-9 in Predicting Non –Resectability in Malignant Obstructive. Jaundice. Bitta C. 1. , Githaiga J. 2. , Kaisha W. 2. 1. Webuye District Hospital. 2. School of Medicine, University of Nairobi. Correspondence to: Dr Ceaser Bitta, P.O.BOX 25-50205 Webuye, Kenya. Email: cbittas@yahoo.com. Abstract.

  15. 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

  16. Two cases of severe acute pancreatitis. CT scan was useful to the assessment

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Yutaka; Takada, Shinichi; Morita, Yoku; Taoka, Yoshio

    1987-06-01

    We report two cases of severe acute pancreatitis; a 53-year-old man (Case 1) and a 60-year-old woman (Case 2). Case 1 was classified as ''severe'' according to the Ranson's criteria and he died of MOF on the 21st hospital day. Case 2 was classified as ''moderate'', but a large pancreatic abscess was observed by CT scan. She died of this abscess complicated with duodenal perforation on the 33rd hospital day. CT findings showed that this case was not ''moderate'' but ''severe''. Therefore, we believe that the findings of CT scan are an important factor for assessment of the severity of acute pancreatitis.

  17. Virtual planning of dental implant placement using CT double scan-technique - own experience

    International Nuclear Information System (INIS)

    Wojciechowski, W.; Urbanik, A.; Kownacki, P.; Kownacki, S.

    2007-01-01

    The correctness of CT performed with the use of a double-scan technique is the basis for achieving proper quality of 3D reconstructions of the maxilla or mandible and subsequent virtual planning of dental implant placement. The aim of this study was the presentation of the methodology of computed tomography scanning and own experience with the use of the double-scan technique. The study group included 26 individuals who underwent MDCT with a double-scan technique using a MDCT scanner SOMATOM Sensation (Siemens, Germany). The parameters of the examination: slice-collimation 10 x 0.75 mm, slice-thickness 0.75 mm. The first CT scan in the procedure was the scan of the patient wearing a radiological prosthesis and occlusal index, which was followed by a separate scan of the radiological prosthesis. These two CT scans were copied and transferred to PC with Procera Software program (Nobel Biocare, Sweden) where dental implant placement was virtually planned. In all 26 patients, precise three-dimensional reconstructions of the anatomical structure were obtained. In 11 patients, on the basis of the virtual planning, the implant placement was performed, 5 patients were referred to preparatory procedures, that is, restoration of the alveolar process, otolaryngological treatment of the maxillary sinuses. The remaining 10 patients did not qualify to the procedure because of unfavorable anatomical ideation's. Correct computed tomography with double-scan technique enables virtual planning of dental implant placement, on the basis of which the real procedure of implantation can be performed. (author)

  18. [Diagnostic value of CT scan for AO B3 fracture of distal radius].

    Science.gov (United States)

    Li, S L; Wang, M Y; Lu, Y

    2017-08-18

    To determine whether 3-dimentional CT scans is able to effectively improve the detection rate of AO B3 distal radius fractures in clinics. From Jan 2013 to Jan 2014, 30 patients with distal radius fractures were retrospectively enrolled in this study, all the patients directly visited the skeletal trauma emergency department in Beijing Jishuitan Hospital post injury and all of them accepted open reduction and internal fixation of distal radius fractures at last. All the radiographic data including X ray films and 3-dimentional CT scans of these patients were collected. Two independent observers were required to make primary AO classifications for each fracture by X rays at first, then to make final AO classifications by 3-dimentional CT scans. Finally, the detection rates of CT scans and plain films for AO B3 distal radius fractures and B3.3 distal radius fractures were compared, the agreements of the two methods for diagnosing AO B3 and B3.3 fractures were calculated by Cohen's Kappa calculations. All the 30 fractures were confirmed to be AO B3 distal radius fractures intraoperatively, and 10 of them were B3.3 fractures. The results were completely consistent with the results of 3-dimensional CT scans. However, only 80%(24/30) AO B3 distal radius fractures and 60%(6/10) B3.3 distal radius fractures could be diagnosed only by X rays. The detection rate of CT scans was proved to be significantly higher than X rays for diagnosing B3 distal radius fractures(100% vs. 80%,PAO B3 distal radius fracture and B3.3 distal radius fracture (kappa=0). Most importantly, in the study process, two special kinds of B3 distal radius fracture were initially found and described by us. One was named as radial B3 fracture, and the other was named as ulna B3 fracture. 3-dimentional CT scans can effectively improve the detection rate of B3 and B 3.3 distal radius fractures, and also help find two special kinds of B3 fractures.

  19. Use of CA-125 Tests and CT Scans for Surveillance in Ovarian Cancer

    Science.gov (United States)

    Esselen, Katharine M.; Cronin, Angel M.; Bixel, Kristin; Bookman, Michael A.; Burger, Robert A.; Cohn, David E.; Cristea, Mihaela; Griggs, Jennifer J.; Levenback, Charles F.; Mantia-Smaldone, Gina; Meyer, Larissa A.; Matulonis, Ursula A.; Niland, Joyce C.; Sun, Charlotte; O’Malley, David M.; Wright, Alexi A.

    2016-01-01

    Importance A 2009 randomized clinical trial (RCT) demonstrated that using CA-125 tests for routine surveillance in ovarian cancer increases chemotherapy use and decreases patients’ quality of life without improving survival, compared with clinical observation. The Society of Gynecologic Oncology guidelines categorize CA-125 testing as “optional” and discourage the use of radiographic imaging for routine surveillance. To date, few studies have examined their use in clinical practice. Objective To examine the use of CA-125 tests and CT scans in clinical practice before and after the 2009 RCT and estimate the economic impact of surveillance testing. Design Prospective cohort of women diagnosed with ovarian cancer between 2004-2011 and followed through 2012. Setting Six National Cancer Institute-Designated Cancer Centers. Participants 1,241 women with ovarian cancer in clinical remission after completion of primary cytoreductive surgery and chemotherapy. Main Outcome Measures Use of CA-125 tests and CT scans before and after 2009 (n=1,241). Secondary outcomes included: the time from CA-125 doubling to retreatment among women who experienced a rise in CA-125 (n=511) before and after 2009, and the costs associated with surveillance testing using 2016 Medicare reimbursement rates. Results Use of CA-125 testing and CT scans was very similar over the study period. During 12 months of surveillance, the cumulative incidence of 3 or more CA-125 tests was 86% in 2004-2009 versus 91% in 2010-2012 (P=.95), and the cumulative incidence of more than 1 CT scan was 81% (2004-2009) versus 78% (2010-2012) (P=.50). Among women who experienced a CA-125 doubling (n=511), there was no significant difference in the time to retreatment with chemotherapy before and after 2009 (median: 2.8 months vs. 3.5 months, P=.40). Over a 12-month period, there were a mean of 4.6 CA-125 tests and 1.7 CT scans per patient, resulting in a United States population surveillance cost estimate of $1

  20. Why proceed to invasive neuroradiological procedures when the CT scan is negative

    International Nuclear Information System (INIS)

    Tatler, G.L.V.; Moseley, I.F.

    1980-01-01

    The notes of a group of National Hospital patients having invasive neuroradiological procedures after a CT examination which was normal or showed non-focal cerebral atrophy have been reviewed. The results of the scans and the subsequent contrast studies have been analysed with respect to the type of contrast study requested and the supposed indications. An attempt has been made to assess retrospectively whether the contrast examinations were germane and whether they had a positive effect on the management of the patient. The large majority of the invasive investigations were non-contributory in any positive sense. The performance of the contrast studies in elucidating mass lesions missed at CT was not impressive. Structural lesions are effectively excluded by CT in a large proportion of cases and normal CT results in the presence of certain symptom complexes (epilepsy, migraine, dementia, loss of consciousness) may rule out the necessity for further investigation. (C.F.)

  1. CT scans of giant aneurysms in the vertebro-basilar artery

    International Nuclear Information System (INIS)

    Shishido, Toyofumi; Ohsugi, Tamotsu; Motozaki, Takahiko; Sakaki, Saburo; Matsuoka, Kenzo

    1980-01-01

    Clinical course and neurological and neuroradiological findings of giant aneurysms in the vertebro-basilar artery observed in two of our cases were discussed. The first case was a 66-year-old man. He complained of sensory disturbance over his left face and unstable gait for 2 years before admission. Neurological examinations on admission showed hypesthesia in the territory of the second branch of the left fifth cranial nerve, nystagmus, and a left cerebellar sign. No mental deterioration or pyramidal signs were noticed. Retrograde left brachial artery angiograms revealed a giant aneurysm with inferior pointing measuring 30 x 10 mm in diameter arising from the left superior cerebellar artery. Precontrast CT scans demonstrated a round, large, high-density area, cantaining a relatively low-density area within it, in the medioventral portion of the left cerebellum; a part of this high-density area was markedly enhanced in the postcontrast CT scan. No ventricular dilatations were noticed by CT scans. Direct surgery was abandoned due to the size and location of the aneurysm. No neurologically abnormal finding developed after discharge. The second case was a 61-year-old man. He complained of unstable gait for 2 years before admission. Neurological examinations on admission showed bilateral pyramidal sings (more pronounced on the left) and nystagmus. There were no cranial nerve palsy and no sensory disturbances. Precontrast CT scans showed a large, oval, high-density area in the medioventral portion of the right cerebellum, extending to the upper brainstem; a part of this high-density area was markedly enhanced in the postcontrast CT scans. Retrograde left brachial artery angiograms revealed that the fusiform aneurysm in the left vertebral, the basilar artery, and the dilated basilar artery ran 30 mm from the clivus, with a dorsal convex arch. (J.P.N.)

  2. Coronal CT scan measurements and hearing evolution in enlarged vestibular aqueduct syndrome.

    Science.gov (United States)

    Saliba, Issam; Gingras-Charland, Marie-Eve; St-Cyr, Karine; Décarie, Jean-Claude

    2012-04-01

    To assess the correlation between the enlarged vestibular aqueduct (EVA) diameter and (1) the hearing loss level (mild, moderate, severe and profound and (2) the hearing evolution. The secondary objective was to obtain measurement limits on the coronal plane of the temporal bone CT scan for the diagnosis of EVA. Retrospective study in a tertiary pediatric center. Mastoid CT scans were reviewed to measure the VA diameter at its midpoint and operculum on axial and coronal planes in a pathologic and normal population. We used their serial audiograms to assess the evolution of hearing. 101 EVA was identified out of 1812 temporal bones CT scan from our radiologic database in 8 years. Bone conduction was stable after a mean follow-up of 40.9 ± 32.9 months. PTA has been the most affected in time by the EVA (p=0.006). No correlation was identified between impedancemetry and the diameter of the EVA. On the diagnostic audiogram, 61% of hearing loss were in the mild and moderate hearing levels; at the end of the follow-up 64% of hearing loss are still in the mild and moderate hearing levels. The cut-off values for the coronal midpoint and operculum planes on the CT scan to diagnose an EVA are 2.4 mm and 4.34 mm respectively. Conductive or mixed hearing loss might be the first manifestation of EVA. Coronal CT scan cuts can provide additional information to evaluate EVA especially when axial cuts are not conclusive. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  3. 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.

  4. "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.

  5. Intracranial ring enhancing lesions in dogs: a correlative CT scanning and neuropathologic study

    International Nuclear Information System (INIS)

    Wolf, Michael; Pedroia, Vince; Higgins, Robert J.; Koblik, Philip D.; Turrel, Jane M.; Owens, Jerry M.

    1995-01-01

    This retrospective analysis of 15 dogs with postcontrast ring enhancing brain lesions, each detected by a single Computed Tomography (CT) examination, searched for any association between their CT appearance and the pathologic diagnosis. In a subgroup of these dogs (n = 71) necropsied within 2 days of the last CT scan, we evaluated whether there was any anatomic correlation between the ring zone and the histopathologic features of the lesions. Our study consisted of eight dogs with primary brain tumors (3 meningiomas, 3 astrocytomas, 1 mixed glioma, 1 oligodendroglioma), 4 with metastatic brain tumors (2 fibrosarcomas, 1 mammary carcinoma, 1 melanoma) and 3 with non-neoplastic brain lesions (2 intraparenchymal hemorrhages, 1 pyogranulomatous meningoencephalitis). The overall size and shape of the contrast enhancing CT lesions, as well as the thickness, surface texture and degree of enhancement of the ring were subjectively evaluated. No association was found between the CT lesion characteristics and the pathologic diagnosis. In the sub-group of dogs euthanatized within 2 days of the CT examination, distinct histologic features which anatomically correlated with the zone of ring enhancement were found in 3 of 7 lesions. The findings of this study are consistent with those of ring-enhancing lesions in people, and indicates that CT ring enhancement is a nonspecific phenomenon which can occur in a variety of neoplastic and non-neoplastic lesions in the dog

  6. 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.

  7. Doses from pediatric CT examinations in Norway: are pediatric scan protocols developed and in daily use?

    International Nuclear Information System (INIS)

    Friberg, Eva G.

    2008-01-01

    Doses to pediatric patients from CT examinations are known to be unnecessarily high if scan protocols developed for adult patients are adopted. This overexposure is most often not recognized by the operating radiographer, due to the digital behavior of the imaging system. Use of optimized size-specific pediatric scan protocols is therefore essential to keep the doses at an appropriate level. The aim of this study was to investigate the doses to pediatric patients from CT examinations and to evaluate the level of optimization of the scan protocols. Patient data, applied scan parameters together with the dose parameters volume computed tomography dose index (CTD vol ) and dose length product (DLP) for examinations of the head, chest and abdomen were collected by means of a questionnaire from five university hospitals. The effective dose was estimated from the total DLP by use of region-specific conversion coefficients (E DLP ). Totally 136, 108 and 82 questionnaires were received for examinations of the head, chest and abdomen, respectively. Large variations in patient doses between the hospitals were observed, addressing the need for optimization of the scan protocols in general. Most of the hospitals applied successive lower mAs with decreasing patient age for all scan areas, while the use of lower tube voltage for small patients and a higher tube voltage for large patients were more rarely. This indicates the presence, to a certain level, of size specific scan protocols at some Norwegian hospitals. Focus on developing size-specific scan protocols for pediatric patients are important to reduce the doses and risks associated with pediatric CT examinations. (author)

  8. Automated bone removal in CT angiography : Comparison of methods based on single energy and dual energy scans

    NARCIS (Netherlands)

    van Straten, Marcel; Schaap, Michiel; Dijkshoorn, Marcel L.; Greuter, Marcel J.; van der Lugt, Aad; Krestin, Gabriel P.; Niessen, Wiro J.

    2011-01-01

    Purpose: To evaluate dual energy based methods for bone removal in computed tomography angiography (CTA) images and compare these with single energy based methods that use an additional, nonenhanced, CT scan. Methods: Four different bone removal methods were applied to CT scans of an anthropomorphic

  9. The Use of CT Scans in Estimating Age at Death by Examining the Extent of Ectocranial Suture Closure

    DEFF Research Database (Denmark)

    Boyd, Kristen Leigh; Villa, Chiara; Lynnerup, Niels

    2015-01-01

    We examined the utility of CT scans in the evaluation of degree of ectocranial suture closure. Five cranial points (left and right midcoronal positions, left and right midlambdoidal positions, and the lambda) were evaluated in 231 CT scans using a three-point scoring system (open, partial closed,...

  10. Assessment value of quantitative indexes of pancreatic CT perfusion scanning for malignant degree of pancreatic cancer

    Directory of Open Access Journals (Sweden)

    Jiang-Xia Lei

    2016-10-01

    Full Text Available Objective: To analyze the assessment value of the quantitative indexes of pancreatic CT perfusion scanning for malignant degree of pancreatic cancer. Methods: A total of 58 patients with space-occupying pancreatic lesions were divided into 20 patients with pancreatic cancer and 38 patients with benign pancreatic lesions after pancreatic CT perfusion. Patients with pancreatic cancer received palliative surgery, and the cancer tissue and para-carcinoma tissue specimens were collected during operation. The differences in pancreatic CT perfusion scanning parameter values and serum tumor marker levels were compared between patients with pancreatic cancer and patients with benign pancreatic lesions, mRNA expression levels of malignant molecules in pancreatic cancer tissue and para-carcinoma tissue were further determined, and the correlation between pancreatic CT perfusion scanning parameter values and malignant degree of pancreatic cancer was analyzed. Results: CT perfusion scanning BF, BV and Per values of patients with pancreatic cancer were lower than those of patients with benign pancreatic lesions; serum CA19-9, CEA, CA125 and CA242 levels were higher than those of patients with benign pancreatic lesions (P<0.05; mRNA expression levels of Bcl-2, Bcl-xL and survivin in pancreatic cancer tissue samples were higher than those in paracarcinoma tissue samples, and mRNA expression levels of P53 and Bax were lower than those in para-carcinoma tissue samples (P<0.05; CT perfusion scanning parameters BF, BV and Per values of patients with pancreatic cancer were negatively correlated with CA19-9, CEA, CA125 and CA242 levels in serum as well as mRNA expression levels of Bcl-2, Bcl-xL and survivin in pancreatic cancer tissue, and positively correlated with mRNA expression levels of P53 and Bax in pancreatic cancer tissue (P<0.05. Conclusions: Pancreatic CT perfusion scanning is a reliable way to judge the malignant degree of pancreatic cancer and plays a

  11. Achieving Routine Submillisievert CT Scanning: Report from the Summit on Management of Radiation Dose in CT

    Science.gov (United States)

    Chen, Guang Hong; Kalender, Willi; Leng, Shuai; Samei, Ehsan; Taguchi, Katsuyuki; Wang, Ge; Yu, Lifeng; Pettigrew, Roderic I.

    2012-01-01

    This Special Report presents the consensus of the Summit on Management of Radiation Dose in Computed Tomography (CT) (held in February 2011), which brought together participants from academia, clinical practice, industry, and regulatory and funding agencies to identify the steps required to reduce the effective dose from routine CT examinations to less than 1 mSv. The most promising technologies and methods discussed at the summit include innovations and developments in x-ray sources; detectors; and image reconstruction, noise reduction, and postprocessing algorithms. Access to raw projection data and standard data sets for algorithm validation and optimization is a clear need, as is the need for new, clinically relevant metrics of image quality and diagnostic performance. Current commercially available techniques such as automatic exposure control, optimization of tube potential, beam-shaping filters, and dynamic z-axis collimators are important, and education to successfully implement these methods routinely is critically needed. Other methods that are just becoming widely available, such as iterative reconstruction, noise reduction, and postprocessing algorithms, will also have an important role. Together, these existing techniques can reduce dose by a factor of two to four. Technical advances that show considerable promise for additional dose reduction but are several years or more from commercial availability include compressed sensing, volume of interest and interior tomography techniques, and photon-counting detectors. This report offers a strategic roadmap for the CT user and research and manufacturer communities toward routinely achieving effective doses of less than 1 mSv, which is well below the average annual dose from naturally occurring sources of radiation. © RSNA, 2012 PMID:22692035

  12. [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.

  13. Analysis of thyroid absorbed dose in cervical CT scan with the use of bismuth shielding

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Fernanda S.; Gómez, Álvaro M.L.; Mourão, Arnaldo P., E-mail: fernanda.stephaniebh@yahoo.com.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Engenharia Nuclear; Santana, Priscila C. [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Departamento de Anatomia e Imagem

    2017-07-01

    The Computed Tomography (CT) has become an important tool to diagnose cancer and to obtain additional information for different clinical questions. Today, it is a very fast, painless and noninvasive test that can be performed high quality images. However, CT scan usually requires a higher radiation exposure dose than a conventional radiography examination. The aim of this study is to determine the dose variation deposited in thyroid and in nearby radiosensitive organs, such as: lenses, pharynx, hypophysis, salivary gland and spinal cord with and without the use of bismuth shielded. A cervical CT scan was performed on anthropomorphic male phantom model Alderson Rando, from the occipital to the first thoracic vertebra, using a GE scanner, Discovery model with 64 channels. Dose measurements have been performed by using radiochromic film strips to register the individual doses in the organs of interest. After the phantom cervical CT scan the radiochromic film strips were processed for obtaining digital images. Digital images were worked to obtain the dose variation profiles for each film. With the data obtained, it was found the organ dose variation. The results show that the thyroid received the highest dose, 40.9 mGy, in the phantom, according to the incidence of the primary X-ray beam. (author)

  14. 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.

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

    International Nuclear Information System (INIS)

    Pacheco de Freitas C, I.; Prata M, A.; Alonso, T. C.; Santana, P.

    2016-10-01

    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)

  16. National Survey of Radiation Dose and Image Quality in Adult CT Head Scans in Taiwan.

    Directory of Open Access Journals (Sweden)

    Chung-Jung Lin

    Full Text Available The purpose of the present study was to evaluate the influence of different variables on radiation dose and image quality based on a national database.Taiwan's Ministry of Health and Welfare requested all radiology departments to complete a questionnaire for each of their CT scanners. Information gathered included all scanning parameters for CT head scans. For the present analysis, CT machines were divided into three subgroups: single slice CT (Group A; multi-detector CT (MDCT with 2-64 slices (Group B; and MDCT with more than 64 slices (Group C. Correlations between computed tomography dose index (CTDI and signal-to-noise ratio (SNR with cumulated tube rotation number (CTW(n and cumulated tube rotation time (CTW(s, and sub group analyses of CTDI and SNR across the three groups were performed.CTDI values demonstrated a weak correlation (r = 0.33 with CTW(n in Group A. SNR values demonstrated a weak negative correlation (r = -0.46 with CTW(n in Group C. MDCT with higher slice numbers used more tube potential resulting in higher effective doses. There were both significantly lower CTDI and SNR values in helical mode than in axial mode in Group B, but not Group C.CTW(n and CTW(s did not influence radiation output. Helical mode is more often used in MDCT and results in both lower CTDI and SNR compared to axial mode in MDCT with less than 64 slices.

  17. 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)

  18. 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).

  19. Estimation of the total effective dose from low-dose CT scans and radiopharmaceutical administrations delivered to patients undergoing SPECT/CT explorations.

    Science.gov (United States)

    Montes, Carlos; Tamayo, Pilar; Hernandez, Jorge; Gomez-Caminero, Felipe; García, Sofia; Martín, Carlos; Rosero, Angela

    2013-08-01

    Hybrid imaging, such as SPECT/CT, is used in routine clinical practice, allowing coregistered images of the functional and structural information provided by the two imaging modalities. However, this multimodality imaging may mean that patients are exposed to a higher radiation dose than those receiving SPECT alone. The study aimed to determine the radiation exposure of patients who had undergone SPECT/CT examinations and to relate this to the Background Equivalent Radiation Time (BERT). 145 SPECT/CT studies were used to estimate the total effective dose to patients due to both radiopharmaceutical administrations and low-dose CT scans. The CT contribution was estimated by the Dose-Length Product method. Specific conversion coefficients were calculated for SPECT explorations. The radiation dose from low-dose CTs ranged between 0.6 mSv for head and neck CT and 2.6 mSv for whole body CT scan, representing a maximum of 1 year of background radiation exposure. These values represent a decrease of 80-85% with respect to the radiation dose from diagnostic CT. The radiation exposure from radiopharmaceutical administration varied from 2.1 mSv for stress myocardial perfusion SPECT to 26 mSv for gallium SPECT in patients with lymphoma. The BERT ranged from 1 to 11 years. The contribution of low-dose CT scans to the total radiation dose to patients undergoing SPECT/CT examinations is relatively low compared with the effective dose from radiopharmaceutical administration. When a CT scan is only acquired for anatomical localization and attenuation correction, low-dose CT scan is justified on the basis of its lower dose.

  20. Comparative study of paranasal sinus between 16-slice spiral CT coronary reforming imagines and scanning images

    International Nuclear Information System (INIS)

    Lei Ziqiao; Han Ping; Yu Jianming; Chen Yan; Shi Heshui; Liu Yonghua; Yu Qun; Wu Hongying

    2007-01-01

    Objective: To explore the effect of different scanning methods and different constructive arithmetic on displaying the anatomy of ostiomeatal complex (OMC). Methods: Fifty-six patients undergoing paranasal sinus CT were divided into normal group (34 cases) and inflammation group (22 cases). According to scanning methods, all the cases reconstructed with soft tissue arithmetic were divided into coronary reforming group and coronary scanning group. Among 56 cases, 18 normal cases and 16 inflammation cases were reconstructed using high resolution arithmetic simultaneously. The imaging quality of OMC was assessed with different scanning methods and different constructive arithmetic. Results: There are no significant difference between coronary reforming images and coronary scanning images in two groups. There are significant difference between high resolution arithmetic and soft tissue arithmetic in normal group, but not in inflammation group. Conclusions: The information of axial images and coronary reforming images with 16-slice CT is superior to coronary scanning images on displaying the anatomy of OMC. High resolution arithmetic is better in displaying the tiny structure of OMC than soft tissue arithmetic in normal group. (authors)

  1. 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

    Mimics software, and BSA values were automatically extracted from the program. They were compared with nine predictive equations from the literature. Remarkably, close correlations (r > 0·90) were found between BSA values from CT scans and those from the predictive formulae. A mean BSA of the 54 cadavers...... of 1·84-1·87 m(2) was calculated by all formulae except one, SD values varying between 0·171 and 0·223 m(2) . T-tests revealed significant differences between mean BSA values calculated with CT and three of the formulae. Regression analyses showed intercepts >(0;0) and slopes

  2. Computed tomography automatic exposure control techniques in 18F-FDG oncology PET-CT scanning.

    Science.gov (United States)

    Iball, Gareth R; Tout, Deborah

    2014-04-01

    Computed tomography (CT) automatic exposure control (AEC) systems are now used in all modern PET-CT scanners. A collaborative study was undertaken to compare AEC techniques of the three major PET-CT manufacturers for fluorine-18 fluorodeoxyglucose half-body oncology imaging. An audit of 70 patients was performed for half-body CT scans taken on a GE Discovery 690, Philips Gemini TF and Siemens Biograph mCT (all 64-slice CT). Patient demographic and dose information was recorded and image noise was calculated as the SD of Hounsfield units in the liver. A direct comparison of the AEC systems was made by scanning a Rando phantom on all three systems for a range of AEC settings. The variation in dose and image quality with patient weight was significantly different for all three systems, with the GE system showing the largest variation in dose with weight and Philips the least. Image noise varied with patient weight in Philips and Siemens systems but was constant for all weights in GE. The z-axis mA profiles from the Rando phantom demonstrate that these differences are caused by the nature of the tube current modulation techniques applied. The mA profiles varied considerably according to the AEC settings used. CT AEC techniques from the three manufacturers yield significantly different tube current modulation patterns and hence deliver different doses and levels of image quality across a range of patient weights. Users should be aware of how their system works and of steps that could be taken to optimize imaging protocols.

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

    International Nuclear Information System (INIS)

    Aleme, C.; Mourao, A. P.; Lyra, M. A.

    2014-08-01

    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)

  4. 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)

  5. 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)

  6. Evaluation of variation of voltage (kV) absorbed dose in chest CT scans

    International Nuclear Information System (INIS)

    Mendonca, Bruna G.A.; Mourao, Arnaldo P.

    2013-01-01

    Computed tomography (CT) is one of the most important diagnostic techniques images today. The increasing utilization of CT implies a significant increase of population exposure to ionizing radiation. Optimization of practice aims to reduce doses to patients because the image quality is directly related to the diagnosis. You can decrease the amount of dose to the patient, and maintain the quality of the image. There are several parameters that can be manipulated in a CT scan and these parameters can be used to reduce the energy deposited in the patient. Based on this, we analyzed the variation of dose deposited in the lungs, breasts and thyroid, by varying the supply voltage of the tube. Scans of the thorax were performed following the protocol of routine chest with constant and variable current for the same applied voltage. Moreover, a female phantom was used and thermoluminescent dosimeters (TLD-100), model bat, were used to record the specific organ doses. Scans were performed on a GE CT scanner, model 64 Discovery channels. Higher doses were recorded for the voltage of 120 kV with 200 mAs in the lungs (22.46 mGy) and thyroid (32.22 mGy). For scans with automatic mAs, variable between 100 and 440, this same tension contributed to the higher doses. The best examination in terms of the dose that was used with automatic 80 kV mAs, whose lungs and thyroid received lower dose. For the best breast exam was 100 kV. Since the increase in the 80 kV to 100 kV no impact so much the dose deposited in the lungs, it can be concluded that lowering the applied voltage to 100 kV resulted in a reduction in the dose absorbed by the patient. These results can contribute to optimizing scans of the chest computed tomography

  7. Study of CT Scan Flooding System at High Temperature and Pressure

    Science.gov (United States)

    Chen, X. Y.

    2017-12-01

    CT scan flooding experiment can scan micro-pore in different flooding stages by the use of CT scan technology, without changing the external morphology and internal structure of the core, and observe the distribution characterization in pore medium of different flooding fluid under different pressure.thus,it can rebuilt the distribution images of oil-water distribution in different flooding stages. However,under extreme high pressure and temperature conditions,the CT scan system can not meet the requirements. Container of low density materials or thin shell can not resist high pressure,while high density materials or thick shell will cause attenuation and scattering of X-ray. The experiment uses a simple Ct scanning systems.X ray from a point light source passing trough a micro beryllium shell on High pressure stainless steal container,continuously irradiates the core holder that can continuously 360° rotate along the core axis. A rare earth intensifying screen behind the core holder emitting light when irradiated with X ray can show the core X ray section image. An optical camera record the core X ray images through a transparency high pressure glazing that placed on the High pressure stainless steal container.Thus,multiple core X ray section images can reconstruct the 3D core reconstruction after a series of data processing.The experiment shows that both the micro beryllium shell and rare earth intensifying screen can work in high temperature and high pressure environment in the stainless steal container. This way that X-ray passes through a thin layer of micro beryllium shell , not high pressure stainless steal shell,avoid the attenuation and scattering of X-ray from the container shell,while improving the high-pressure experiment requirements.

  8. Short- and long-term effects of clinical audits on compliance with procedures in CT scanning

    International Nuclear Information System (INIS)

    Oliveri, Antonio; Howarth, Nigel; Gevenois, Pierre Alain; Tack, Denis

    2016-01-01

    To test the hypothesis that quality clinical audits improve compliance with the procedures in computed tomography (CT) scanning. This retrospective study was conducted in two hospitals, based on 6950 examinations and four procedures, focusing on the acquisition length in lumbar spine CT, the default tube current applied in abdominal un-enhanced CT, the tube potential selection for portal phase abdominal CT and the use of a specific ''paediatric brain CT'' procedure. The first clinical audit reported compliance with these procedures. After presenting the results to the stakeholders, a second audit was conducted to measure the impact of this information on compliance and was repeated the next year. Comparisons of proportions were performed using the Chi-square Pearson test. Depending on the procedure, the compliance rate ranged from 27 to 88 % during the first audit. After presentation of the audit results to the stakeholders, the compliance rate ranged from 68 to 93 % and was significantly improved for all procedures (P ranging from <0.001 to 0.031) in both hospitals and remained unchanged during the third audit (P ranging from 0.114 to 0.999). Quality improvement through repeated compliance audits with CT procedures durably improves this compliance. (orig.)

  9. Routine early CT scanning after craniotomy: is it effective for the early detection of postoperative intracranial hematoma?

    Science.gov (United States)

    Wen, Liang; Yang, Xiao-Feng; Jiang, Hao; Wang, Hao; Zhan, Ren-Ya

    2016-08-01

    Postoperative intracranial hematoma (POIH) is a frequent sequela secondary to cranial surgery. The role of routine early postoperative computed tomography (CT) scanning in the detection of POIH remains controversial. The study was aimed at analyzing the effect of routine early CT scanning after craniotomy for the early detection of POIH. Routine early postoperative CT scanning was performed at our institute, and a retrospective study was conducted to analyze the data. POIH was defined as an intracranial hematoma requiring surgical management. A total of 1,148 patients undergoing craniotomy were included in this study; 28 of these patients developed POIH. The majority of POIH cases (15/28, 54 %) were detected during the first 6 h following craniotomy. A routine CT scan was performed on all included patients but two; however, CT scans detected only 16 POIH cases. During the first 6 h, the rate at which CT scans detected POIH was 1.9 % (15/786); subsequently, the rate decreased to only 0.3 % (1/360; p craniotomy CT scan detected POIH was only 0.7 % (5/721) (p craniotomy. However, if the strategy for routine scanning can be improved, its effect may be beneficial.

  10. 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.

  11. Leukemia and brain tumors among children after radiation exposure from CT scans: design and methodological opportunities of the Dutch Pediatric CT Study.

    Science.gov (United States)

    Meulepas, Johanna M; Ronckers, Cécile M; Smets, Anne M J B; Nievelstein, Rutger A J; Jahnen, Andreas; Lee, Choonsik; Kieft, Mariëtte; Laméris, Johan S; van Herk, Marcel; Greuter, Marcel J W; Jeukens, Cécile R L P N; van Straten, Marcel; Visser, Otto; van Leeuwen, Flora E; Hauptmann, Michael

    2014-04-01

    Computed tomography (CT) scans are indispensable in modern medicine; however, the spectacular rise in global use coupled with relatively high doses of ionizing radiation per examination have raised radiation protection concerns. Children are of particular concern because they are more sensitive to radiation-induced cancer compared with adults and have a long lifespan to express harmful effects which may offset clinical benefits of performing a scan. This paper describes the design and methodology of a nationwide study, the Dutch Pediatric CT Study, regarding risk of leukemia and brain tumors in children after radiation exposure from CT scans. It is a retrospective record-linkage cohort study with an expected number of 100,000 children who received at least one electronically archived CT scan covering the calendar period since the introduction of digital archiving until 2012. Information on all archived CT scans of these children will be obtained, including date of examination, scanned body part and radiologist's report, as well as the machine settings required for organ dose estimation. We will obtain cancer incidence by record linkage with external databases. In this article, we describe several approaches to the collection of data on archived CT scans, the estimation of radiation doses and the assessment of confounding. The proposed approaches provide useful strategies for data collection and confounder assessment for general retrospective record-linkage studies, particular those using hospital databases on radiological procedures for the assessment of exposure to ionizing or non-ionizing radiation.

  12. 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.

  13. Determining compliance of ear CT scan with interaoperative findings in deaf children with cochlear implantation.

    Science.gov (United States)

    Mohammad, Ajalloueyan; Mohammad Bagher, Sadeghi; Mahdi, Mirmohammad; Zahra, Ajalloueyan

    2015-08-01

    Defecated or impaired hair cell function of the cochlea causes deafness. Cochlear implantation allows transmission of sound information through central auditory pathways using direct electric stimulation of auditory nerve dendrites. Using radiologic imaging, including CT scan is very helpful in selection of candidates and evaluation after implantation. The purpose of this study is to determine compliance of CT findings in deaf children undergoing cochlear implantation compared with the intra-operative findings. In a periodical-descriptive study, 100 patients (56 male and 44 female), 6 months to 6 years of age, who were candidates for cochlear implantation at Baqiyatallah Hospital in Tehran between January 2010 and October 2011, were studied. After getting informed consent form the parents of patients, demographic data was recorded. CT scan and surgical data were double blindly collected in the designed questionnaire which was approved by three radiologists and three ENT specialists. Finally, surgical and radiological data were compared and t-test and chi-square test was used. Atic status in 89 patients (89%) was statistically significant between radiology and surgery (P=0.06). Positive Predictive Value and Negative Predictive Value were respectively 100 and 92.8. Middle ear space was same in 85 patients (85%) in the two methods (P=0.01) (NVP=63.4). Pyramid status was similar in radiology and surgery results in 67 patients (67%) (P=0.000) and PPV and NPV were 100 and 63.4 respectively. Jugular bulb was similar in 73 patients (73%) (P=0.00). There was no significant difference between other modalities. In most cases examined in this study, compliance between the surgical and radiological findings was above 80%. In some cases, CT scan could give confidence to the surgeon, but in atic, middle ear space, pyramid and jugular bulb there might be insufficient reliance to CT findings and there would be need to more accurate observation during surgery. Copyright © 2015

  14. 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...... supplied algorithm (method I). A significant deviation of volume fraction from method I was found: both the y-intercept and the slope of the regression line were significantly different from those of the Archimedes-based volume fraction (p ... on a calibration of volume fraction to the Archimedes-based volume fractions (method II). The mean thresholds of the two methods were applied to segment 20 randomly selected specimens. The results showed that volume fraction using the mean threshold of method I was underestimated by 4% (p = 0.001), whereas...

  15. 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.

  16. Nodule detection methods using autocorrelation features on 3D chest CT scans

    International Nuclear Information System (INIS)

    Hara, T.; Zhou, X.; Okura, S.; Fujita, H.; Kiryu, T.; Hoshi, H.

    2007-01-01

    Lung cancer screening using low dose X-ray CT scan has been an acceptable examination to detect cancers at early stage. We have been developing an automated detection scheme for lung nodules on CT scan by using second-order autocorrelation features and the initial performance for small nodules (< 10 mm) shows a high true-positive rate with less than four false-positive marks per case. In this study, an open database of lung images, LIDC (Lung Image Database Consortium), was employed to evaluate our detection scheme as an consistency test. The detection performance for solid and solitary nodules in LIDC, included in the first data set opened by the consortium, was 83% (10/12) true-positive rate with 3.3 false-positive marks per case. (orig.)

  17. The study on fatty infiltration of the liver with the use of CT scan

    International Nuclear Information System (INIS)

    Yamawaki, Tadaharu; Hirofuji, Hideo; Yatomi, Akira; Kawabe, Masami; Sugie, Hajime

    1981-01-01

    On the basis of experience thus far, it is said that the diagnosis of fatty liver is comparatively difficult. It has been reported that the diagnosis of fatty liver can be done by its decreased attenuation number on CT scan among diffuse liver diseases. We investigated 80 cases of which attenuation number revealed below 35 Hn (Hounsfield units). Analysis of correlations between eight variables (T. Cholesterol, β-lipoprotein, Triglyceride, HDL Cholesterol, Cholinesterase, Obsity index, BSP and the degree of fatty infiltration of the liver specimen) and mean attenuation number of the liver were investigated and highly significant correlation was found only between the degree of fatty infiltration of the liver and the mean attenuation number of the liver (r = -0.746, p < 0.01). Therefore, it is concluded that CT scan is an epochmaking morphological examination of fatty liver. (author)

  18. Transient gyriform brightness on non-contrast enhanced computed tomography (CT) brain scan of seven infants

    Energy Technology Data Exchange (ETDEWEB)

    Close, P.J.; Carty, H.M. (Royal Liverpool Childrens Hospital (UK))

    1991-04-01

    Spontaneous gyriform brightness seen on CT scan is an unusual finding unless associated with arteriovenous malformations (AVM). There are sporadic case reports in the literature of its occurrence in association with herpex simplex virus encephalitis (HSVE), purulent meningitis, following chemotherapy for leukaemia, in a child with chronic renal failure, and in a child with folic acid deficiency. We present a series of seven cases exhibiting this phenomenon, none of whom have AVMs, who have been scanned at this hospital in the first 2 1/2 years following the installation of a CT scanner. Four of the cases had congenital heart disease requiring corrective surgery or cardiac catheterisation. The other three had probable meningo-encephalitis. In all cases the gyriform brightness followed an ischaemic insult to the child's brain. We hypothesise that this phenomenon is an ischaemic response in the immature brain and that its occurrence is not so rare as the literature may suggest. (orig.).

  19. Improving Spleen Volume Estimation Via Computer-assisted Segmentation on Clinically Acquired CT Scans.

    Science.gov (United States)

    Xu, Zhoubing; Gertz, Adam L; Burke, Ryan P; Bansal, Neil; Kang, Hakmook; Landman, Bennett A; Abramson, Richard G

    2016-10-01

    Multi-atlas fusion is a promising approach for computer-assisted segmentation of anatomic structures. The purpose of this study was to evaluate the accuracy and time efficiency of multi-atlas segmentation for estimating spleen volumes on clinically acquired computed tomography (CT) scans. Under an institutional review board approval, we obtained 294 de-identified (Health Insurance Portability and Accountability Act-compliant) abdominal CT scans on 78 subjects from a recent clinical trial. We compared five pipelines for obtaining splenic volumes: Pipeline 1 - manual segmentation of all scans, Pipeline 2 - automated segmentation of all scans, Pipeline 3 - automated segmentation of all scans with manual segmentation for outliers on a rudimentary visual quality check, and Pipelines 4 and 5 - volumes derived from a unidimensional measurement of craniocaudal spleen length and three-dimensional splenic index measurements, respectively. Using Pipeline 1 results as ground truth, the accuracies of Pipelines 2-5 (Dice similarity coefficient, Pearson correlation, R-squared, and percent and absolute deviation of volume from ground truth) were compared for point estimates of splenic volume and for change in splenic volume over time. Time cost was also compared for Pipelines 1-5. Pipeline 3 was dominant in terms of both accuracy and time cost. With a Pearson correlation coefficient of 0.99, average absolute volume deviation of 23.7 cm(3), and time cost of 1 minute per scan, Pipeline 3 yielded the best results. The second-best approach was Pipeline 5, with a Pearson correlation coefficient of 0.98, absolute deviation of 46.92 cm(3), and time cost of 1 minute 30 seconds per scan. Manual segmentation (Pipeline 1) required 11 minutes per scan. A computer-automated segmentation approach with manual correction of outliers generated accurate splenic volumes with reasonable time efficiency. Copyright © 2016 The Association of University Radiologists. Published by Elsevier Inc. All

  20. Multidetector computed tomography for the assessment of adnexal Mass: Is unenhenced CT scan necessary?

    International Nuclear Information System (INIS)

    Jung, Sung Il; Park, Hee Sun; Kim, Young Jun; Jeon, Hae Jeong

    2014-01-01

    To compare the diagnostic performance and radiation dose between contrast-enhanced CT (ECT) alone, and combined unenhanced and contrast-enhanced CT (UE + ECT) for the assessment of adnexal mass. This retrospective study was approved by the Institutional Review Board. A total of 146 consecutive patients (mean age, 41.1 years) who underwent preoperative unenhanced and contrast-enhanced multidetector CT of the pelvis and had adnexal masses found at surgery were included. Two readers independently evaluated the likelihood of adnexal malignancy on a 5-point scale on two different imaging datasets (ECT alone and UE + ECT). The area under the receiver operating characteristic curve (AUC) was used to evaluate diagnostic performance. Radiation dose to patients was calculated by the volume CT dose index (CTDIvol) and the dose length products (DLP) on each dataset. Of the total 178 adnexal masses, 133 masses were benign and 45 masses were malignant. For both readers, there is no significant difference of AUC values between ECT alone and UE + ECT for the detection of adnexal malignancy (reader 1, 0.93 vs. 0.95; reader 2, 0.92 vs. 0.91) (p > 0.05). The mean CTDIvol (12.6 ± 2.2 mGy) and DLP (641.2 ± 137.2 mGy) of ECT alone was significantly lower than the mean CTDIvol (21.5 ± 2.7 mGy) and DLP (923.6 ± 158.8 mGy) of UE + ECT (p < 0.0001). The use of unenhanced CT scan in addition to contrast-enhanced CT scan does not improve the detection of adnexal malignancy, but increases radiation exposure.

  1. A case of retrocaval ureter diagnosed by CT scan combined with a ureteral catheter

    International Nuclear Information System (INIS)

    Matsumoto, Atsushi; Iio, Shozo; Toyama, Takashi; Mochizuki, Teruichi

    1986-01-01

    The patient was a 45-year-old male who was admitted for right flank pain, nausea and vomitting. IVP revealed right hydronephrosis and hydroureter with medial distortion at the level of the 3rd lumbar spine. The diagnosis of retrocaval ureter was made with CT scan combined with a ureteral catheter. End to end anastomosis after resection of the retrocaval segment was performed. IVP 21 days after the operation showed that the right hydroureteronephrosis had moderately improved. (author)

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

    OpenAIRE

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

    2016-01-01

    Computerized tomography (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 3x3 microneedle a...

  3. 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.

  4. 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.

  5. 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.

  6. Basal ganglia calcification on CT-scanning in children with acute lymphocytic leukemia

    International Nuclear Information System (INIS)

    Smith, D.; Bloch, S.; Al-Rashid, R.A.

    1980-01-01

    Calcification occurring in the basal ganglia in children with acute hympocytic leukemia following therapy is uncommon and to the best of our knowledge has not been reported prior to therapy. Eleven cases of bilateral symmetrical calcification in the basal ganglia were noted in 2350 CT scans, two being in children with acute lymphocytic leukemia. In one of the two cases, calcification was present prior to therapy. (orig.)

  7. 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.

  8. Differences in MRI findings in cases showing ring-enhancement on a CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Tokiwa, Kaichi; Hashimoto, Takashi; Miyasaka, Yoshio; Yada, Kenzoh; Kan, Shinichi (Kitasato Univ., Sagamihara, Kanagawa (Japan). School of Medicine); Takagi, Hiroshi

    1990-04-01

    It is sometimes difficult to differentiate between a brain abscess and a tumor, for both show ring-enhancement on a CT scan. The present authors have studied the benefit of MRI for the differential diagnosis of these two lesions. The subjects of this study were 6 cases of brain abscess and 10 cases of brain tumor, all of them showing ring-enhancement on a CT scan. The MRI findings were compared with those of the CT scan taken at almost the same time, especially focussing on the difference in the ring-enhancement. In 5 out of the 6 cases of brain abscess, T{sub 2}-weighted MRI demonstrated a comparatively thin and homogeneous low-intensity, round rim. In the cases of brain tumor, however, none of the cases demonstrated this typical low-intensity, round rim; rather, in them the rim was thick and irregular. The authors can conclude that those MRI findings can serve as important differential diagnostic findings between brain abscess and tumor; also, MRI may be used as a landmark for terminating the administration of antibiotics in cases of brain abscess. (author).

  9. Differences in MRI findings in cases showing ring-enhancement on a CT scan

    International Nuclear Information System (INIS)

    Tokiwa, Kaichi; Hashimoto, Takashi; Miyasaka, Yoshio; Yada, Kenzoh; Kan, Shinichi; Takagi, Hiroshi.

    1990-01-01

    It is sometimes difficult to differentiate between a brain abscess and a tumor, for both show ring-enhancement on a CT scan. The present authors have studied the benefit of MRI for the differential diagnosis of these two lesions. The subjects of this study were 6 cases of brain abscess and 10 cases of brain tumor, all of them showing ring-enhancement on a CT scan. The MRI findings were compared with those of the CT scan taken at almost the same time, especially focussing on the difference in the ring-enhancement. In 5 out of the 6 cases of brain abscess, T 2 -weighted MRI demonstrated a comparatively thin and homogeneous low-intensity, round rim. In the cases of brain tumor, however, none of the cases demonstrated this typical low-intensity, round rim; rather, in them the rim was thick and irregular. The authors can conclude that those MRI findings can serve as important differential diagnostic findings between brain abscess and tumor; also, MRI may be used as a landmark for terminating the administration of antibiotics in cases of brain abscess. (author)

  10. The diagnostic value of CT scan and selective venous sampling in Cushing's syndrome

    International Nuclear Information System (INIS)

    Negoro, Makoto; Kuwayama, Akio; Yamamoto, Naoto; Nakane, Toshichi; Yokoe, Toshio; Kageyama, Naoki; Ichihara, Kaoru; Ishiguchi, Tsuneo; Sakuma, Sadayuki

    1986-01-01

    We studied 24 patients with Cushing's syndrome in order to find the best way to confirm the pituitary adenoma preoperatively. At first, the sellar content was studied by means of a high-resolution CT scan in each patient. Second, by selective catheterization in the bilateral internal jugular vein and the inferior petrosal sinus, venous samples (c) were obtained for ACTH assay. Simultaneously, peripheral blood sampling (P) was made at the anterior cubital vein for the same purpose, and the C/P ratio was carefully calculated in each patient. If the C/P ratio exceeded 2, it was highly suggestive of the presence of pituitary adenoma. Even by an advanced high-resolution CT scan with a thickness of 2 mm, pituitary adenomas were detected in only 32 % of the patients studied. The result of image diagnosis in Cushing disease was discouraging. As for the chemical diagnosis, the results were as follows. At the early stage of this study, the catheterization was terminated in the jugular veins of nine patients. Among these, in five patients the presence of pituitary adenoma was predicted correctly in the preoperative stage. Later, by means of inferior petrosal sinus samplings, pituitary microadenomas were detected in ten patients among the twelve. Selective venous sampling for ACTH in the inferior petrosal sinus or jugular vein proved to be useful for the differential diagnosis of Cushing's syndrome when other diagnostic measures such as CT scan were inconclusive. (author)

  11. 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)

  12. Patient radiation protection covers for head CT scans. A clinical evaluation of their effectiveness

    Energy Technology Data Exchange (ETDEWEB)

    Liebmann, M.; Luellau, T.; Poppe, B. [Oldenburg Univ. (Germany). Medical Radiation Physics; Pius-Hospital, Oldenburg (Germany). Clinic for Radiotherapy and Radiooncology; Kluge, A. [Pius-Hospital, Oldenburg (Germany). Inst. for Diagnostic and Interventional Radiology; Boetticher, H. von [Klinikum Links der Weser, Bremen (Germany). Center of Radiology/Nuclear Medicine and Academy of Radiation Protection

    2014-11-15

    Although the use of thyroid shields for patients for head CT examinations is reasonable and even required by German regulations, so far available shields are often not used due to difficult applicability. New shields that are easier to use and therefore may gain wider acceptance and more frequent use are now available. In this work two new patient shields are investigated regarding their dose reduction effectiveness and applicability and compared to a thyroid/sternum shield typically used as a part of personal protective equipment. The reduction of organ doses for thyroid, sternum and mamma were measured with thermoluminescence detectors in an anthropomorphic female phantom. Additionally, the influence of the length or position of the overview scan at the beginning of the CT examination was taken into account. Depending on the patient shield, a reduction of the organ doses for thyroid of 5-24%, for sternum of 25-48% and for mamma of 25-70% could be found. A shift of 25 mm in the cranial direction for the overview scan resulted in a reduction of these organ doses of 12-15%. Patient shields for cranial CT examinations provide a considerable dose reduction. New models are easily applied and no decrease in image quality through reconstruction artifacts could be found. Therefore, it is advised to use shields which are applied upon the patient without the need to be wrapped around the neck and the overview scan should be positioned as close as possible to the examined region.

  13. 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.

  14. 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).

  15. Pedicle measurement of the thoracolumbar spine: a cadaveric, radiographic, and CT scan study in Filipinos

    International Nuclear Information System (INIS)

    Molano, A.M.V.; Sison, A.B.; Fong, H.C.; Lim, N.T.; Sabile, K.

    1994-01-01

    With the popular usage of spinal pedicular screw fixation, it is essential to have a knowledge of the morphometry of the pedicles of the spine of particular populations. This study compared the direct pedicle measurements of ten cadavers in an institution, with their respective radiographic and computerized tomographic (CT) scan values, and also compared the effective pedicle diameter (EPD) with the conventional outer pedicle diameter (OPD) measurements. A compilation of pedicle values was also made in X-ray and CT scan plates of a Filipino population. A statistical analysis made on the 2,760 pedicle measurements taken from cadaveric T6-L5 vertebrae showed that direct measurements were significantly different from X-ray and CT scan values. The mean values of the EPD differed from those of the OPD, but not statistically significant. Comparison with previous foreign studies revealed significant differences in these pedicle dimensions. Pedicle measurements in a living Filipino population were found to be significantly different statistically between sexes. Accurate measurement of the pedicle diameters and lengths are indeed critical for the success of a spinal stabilization procedure using pedicular screws. (author). 8 refs.; 5 figs.; 1 tab

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

    Energy Technology Data Exchange (ETDEWEB)

    Du Plessis, Anne-Marie; Theron, Salomine; Andronikou, Savvas [University of Stellenbosch, Radiology Department, Tygerberg Hospital, Cape Town (South Africa)

    2009-02-15

    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. (orig.)

  17. Differentiation between eclampsia and cerebrovascular disorders by brain CT scan in pregnant patients with convulsive seizures

    International Nuclear Information System (INIS)

    Eguchi, Katsuto; Lin, Yaw-Tyng; Noda, Kiyofumi; Saeki, Kazuhiko; Yonezawa, Masaru; Sekiba, Kaoru; Ochiai, Youji

    1987-01-01

    Six pregnant women with convulsions between 25 to 40 weeks of gestation were experienced. Among them, 4 patients were diagnosed as having intracranial hemorrhage and two as simple eclampsia. With the aid of brain CT scan, one case of arteriovenous malformation was detected and treated surgically with good prognosis for both the mother and the fetus. Two patients were diagnosed to have cerebral hemorrhage with subsequent penetration into the lateral ventricles and were treated conservatively. Their fetuses were delivered alive by cesarean section, but the mothers expired. The other patient with cerebral hemorrhage was treated surgically, and both the mother and the fetus survived. One of the simple eclampsia patients was noted to have a growth retarded fetus at 32 weeks of pregnancy with subsequent intra-uterine death, but the mother recovered after conservative treatment. Another patient at 40 weeks of pregnancy was also treated conservatively and both the fetus and the mother survived. Brain CT scan findings differed between these two eclampsia patients; local brain edema for the second patient and generalized brain edema for the first patient. Thus more active application of brain CT scan is recommended in managing pregnant patients with convulsions. (author)

  18. Differentiation between eclampsia and cerebrovascular disorders by brain CT scan in pregnant patients with convulsive seizures

    Energy Technology Data Exchange (ETDEWEB)

    Eguchi, Katsuto; Lin, Yaw-Tyng; Noda, Kiyofumi; Saeki, Kazuhiko; Yonezawa, Masaru; Sekiba, Kaoru; Ochiai, Youji

    1987-06-01

    Six pregnant women with convulsions between 25 to 40 weeks of gestation were experienced. Among them, 4 patients were diagnosed as having intracranial hemorrhage and two as simple eclampsia. With the aid of brain CT scan, one case of arteriovenous malformation was detected and treated surgically with good prognosis for both the mother and the fetus. Two patients were diagnosed to have cerebral hemorrhage with subsequent penetration into the lateral ventricles and were treated conservatively. Their fetuses were delivered alive by cesarean section, but the mothers expired. The other patient with cerebral hemorrhage was treated surgically, and both the mother and the fetus survived. One of the simple eclampsia patients was noted to have a growth retarded fetus at 32 weeks of pregnancy with subsequent intra-uterine death, but the mother recovered after conservative treatment. Another patient at 40 weeks of pregnancy was also treated conservatively and both the fetus and the mother survived. Brain CT scan findings differed between these two eclampsia patients; local brain edema for the second patient and generalized brain edema for the first patient. Thus more active application of brain CT scan is recommended in managing pregnant patients with convulsions.

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

    International Nuclear Information System (INIS)

    Cho, Young Jun; Kim, Joung Sook; Kim, Ji Young; Choi, Soo Jeon; Choi, Sang Bong

    2008-01-01

    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

  20. 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.

  1. 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

  2. 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

  3. Study of effect of different CT scanning protocols on HU variation and their impact on TPS calculations

    International Nuclear Information System (INIS)

    Mahur, Mamta; Sharma, Richa; Sasindaran, M.; Singh, Anshu; Gedam, Varsha; Negi, P.S.; Grover, R.K.

    2016-01-01

    Computer tomographic (CT) scans are used to correct for tissue inhomogeneties in radiotherapy treatment planning. In order to guarantee a precise treatment, it is important to obtain the relationship between CT Hounsfield units and relative electron densities, which is the basic input for radiotherapy planning systems which consider tissue heterogeneities. The purpose of this study is to investigate the influence of different CT scan parameters (kVp, mAs) on uniformity of CT numbers versus relative electron density (HURED) curves and their different dosimetric impact

  4. 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

  5. Low-Dose CT Scan for Lung Cancer Screening: Clinical and Coding Considerations.

    Science.gov (United States)

    Shieh, Yiwey; Bohnenkamp, Martin

    2017-07-01

    Lung cancer screening with low-dose CT (LDCT) scan was shown to reduce lung cancer mortality in the National Lung Screening Trial, a large randomized controlled trial of high-risk current and former smokers. Despite ongoing uncertainty over the effectiveness of LDCT scan in the real-world setting, the Centers for Medicare and Medicaid Services (CMS) decided to cover LDCT scan as a preventive service. As part of its National Coverage Determination, CMS set forth a series of requirements for reimbursement of LDCT scan, including a counseling and shared decision-making visit prior to a LDCT scan being ordered. During this visit, providers must determine patient eligibility, engage in shared decision-making around LDCT scan, discuss the importance of adherence to screening, and provide smoking cessation counseling (if applicable). Two new billing codes were introduced for the counseling and shared decision-making visit and subsequent LDCT scan. In this review, we summarize the evidence around lung cancer screening and describe practical aspects of the counseling and shared decision-making, including billing considerations. We conclude with a discussion of the greater implications of CMS National Coverage Determination, especially as it pertains to quality assurance around new screening tests. Copyright © 2017 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  6. Estimates of effective dose for CT scans of the lower extremities.

    Science.gov (United States)

    Saltybaeva, Natalia; Jafari, Mary Ellen; Hupfer, Martin; Kalender, Willi A

    2014-10-01

    To determine the dose-length product (DLP)-effective dose (ED) (DLP/ED) conversion coefficient (k) tables for the lower extremities that can be used for calculating ED. Dose calculations were performed on standard phantoms using a validated Monte Carlo calculation tool. Calculations were performed to obtain ED values for tube voltages from 80 kV to 140 kV in steps of 20 kV for the following examinations: hip (femur), knee, ankle, and computed tomographic (CT) angiography of the lower extremities. Values of the DLP were calculated by multiplying measured CT dose index values by the scan length; k values resulted as the quotients of the ED and DLP values. DLP/ED coefficients averaged over the range of voltage values and their standard deviations were determined for the given lower-extremity CT examinations for all age groups and for both sexes. Coefficients depend strongly on the phantom age and size, but little on the kilovolt value. In the case of the newborn, for example, k values were 0.0612, 0.0046, 0.0014, and 0.047 for hip, knee, ankle, and CT angiography, respectively, while in the case of the adult, these respective values were 0.0110, 0.0004, 0.0002, and 0.0062. A substantial difference up to 20% between coefficients in male and female phantoms was observed for CT angiographic examination. DLP/ED conversion coefficients are provided for lower extremities and allow estimation of ED for commonly used clinical musculoskeletal CT and CT angiographic protocols. © RSNA, 2014.

  7. Pengaruh Window Level Dan Window Width Pada Lung Window Dan Mediastinum Window Pada Kualitas Citra CT-Scan Thorax

    OpenAIRE

    Gaol, Syahnaro Lumban

    2015-01-01

    This Research of image CT-SCAN thorax with influence of window level and window width, to obtain, get value of window level and optimal window width lung window and mediastinum window, so that get image of CT-SCAN thorax which with image quality. Image of CT-SCAN thorax obtained for mediastinum window use window width 350, 400, 450, 500 HU. And Window level 50,100,150 HU. While for lung window use window width 1000,1100 HU. The window level - 500-,600,-700,-800,-900,-1000 HU, by three observe...

  8. Prevalence and characteristics of intravertebral enhancement on contrast-enhanced CT scans in cancer patients

    International Nuclear Information System (INIS)

    Rasselet, Benjamin; Larbi, Ahmed; Viala, Pierre; Molinari, Nicolas; Tetreau, Raphael; Faruch-Bilfeld, Marie; Taourel, Patrice; Cyteval, Catherine

    2017-01-01

    Highlights: • 2.8% of collateral venous circulation seen on CT scan in a cancer population. • 37% of intravertebral enhancement in this population with collateral venous circulation. • 80.8% of intravertebral enhancements are located between C6 and. • 73% of intravertebral enhancements are located ipsilateral to the injection side. -  Abstract: Study design: This was a single center, retrospective observational study. Objective: to investigate—in a cancer population—the prevalence and hallmarks of intravertebral enhancement (IVE) detected on contrast-enhanced CT. Summary of background data: Intravertebral enhancements secondary to iodinated contrast stagnation have been described. Cancer patients have an increased risk of perivertebral venous thrombosis or stenosis secondary to several risk factors (cancer or drug induced hypercoagulability, deterioration of venous flow linked to catheter insertion, prolonged immobilization). In case of a high density lesion identified on CT, the diagnostic choice between metastasis and contrast media within bone marrow vessels may be an issue, especially as oncologic follow-up CT scans are usually performed with contrast medium injection. Methods: 2572 contrast-enhanced body CT scans performed in cancer patients over 3 months in the medical imaging department of a university hospital were retrospectively reviewed. IVE was sought when paravertebral venous collateral circulation was detected and bone metastasis ruled out and classified as linear or nodular. Their locations within vertebra, their relation to the injection side and the predominant collateral venous network side were evaluated. Results: Sixty-seven (2.8%) patients had a collateral paravertebral venous system and among them 21 had IVE (37%). There were 208 IVE locations involving 75 vertebrae. 199 IVE were linear-shaped (95.7%) and 9 nodular-shaped (4.3%). 80.8% were located between C6 and T4. 88.9% were localized in the vertebral body. 73.1% were located

  9. Prevalence and characteristics of intravertebral enhancement on contrast-enhanced CT scans in cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Rasselet, Benjamin [Medical Imaging Department and Biostatistics Department, Montpellier University Hospital, 191 Avenue du Doyen Gaston Giraud, 34 295 Montpellier Cedex 5 (France); Larbi, Ahmed; Viala, Pierre [Medical Imaging Department, Nimes University Hospital, 4 rue du Professeur Robert Debré, 30029 Nîmes (France); Molinari, Nicolas [Biostatistics Department, Montpellier University Hospital, 191 Avenue du Doyen Gaston Giraud, 34 295 Montpellier Cedex 5 (France); Tetreau, Raphael [Medical Imaging Department, Montpellier Cancer Institute (ICM), 208 Avenue des Apothicaires, 34298 Montpellier Cedex 5 (France); Faruch-Bilfeld, Marie [Medical Imaging Department, Toulouse University Hospital, Place du Docteur Baylac, 31059 Toulouse Cedex 9 (France); Taourel, Patrice [Medical Imaging Department and Biostatistics Department, Montpellier University Hospital, 191 Avenue du Doyen Gaston Giraud, 34 295 Montpellier Cedex 5 (France); Cyteval, Catherine, E-mail: c-cyteval@chu-montpellier.fr [Medical Imaging Department and Biostatistics Department, Montpellier University Hospital, 191 Avenue du Doyen Gaston Giraud, 34 295 Montpellier Cedex 5 (France)

    2017-01-15

    Highlights: • 2.8% of collateral venous circulation seen on CT scan in a cancer population. • 37% of intravertebral enhancement in this population with collateral venous circulation. • 80.8% of intravertebral enhancements are located between C6 and. • 73% of intravertebral enhancements are located ipsilateral to the injection side. -  Abstract: Study design: This was a single center, retrospective observational study. Objective: to investigate—in a cancer population—the prevalence and hallmarks of intravertebral enhancement (IVE) detected on contrast-enhanced CT. Summary of background data: Intravertebral enhancements secondary to iodinated contrast stagnation have been described. Cancer patients have an increased risk of perivertebral venous thrombosis or stenosis secondary to several risk factors (cancer or drug induced hypercoagulability, deterioration of venous flow linked to catheter insertion, prolonged immobilization). In case of a high density lesion identified on CT, the diagnostic choice between metastasis and contrast media within bone marrow vessels may be an issue, especially as oncologic follow-up CT scans are usually performed with contrast medium injection. Methods: 2572 contrast-enhanced body CT scans performed in cancer patients over 3 months in the medical imaging department of a university hospital were retrospectively reviewed. IVE was sought when paravertebral venous collateral circulation was detected and bone metastasis ruled out and classified as linear or nodular. Their locations within vertebra, their relation to the injection side and the predominant collateral venous network side were evaluated. Results: Sixty-seven (2.8%) patients had a collateral paravertebral venous system and among them 21 had IVE (37%). There were 208 IVE locations involving 75 vertebrae. 199 IVE were linear-shaped (95.7%) and 9 nodular-shaped (4.3%). 80.8% were located between C6 and T4. 88.9% were localized in the vertebral body. 73.1% were located

  10. Prevalence of esophageal cancer during the pretreatment of hypopharyngeal cancer patients: Routinely performed esophagogastroduodenoscopy and FDG-PET/CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Nakaminato, Shuichiro; Toriihara, Akira; Makino, Tomoko; Shibuya, Hitoshi [Dept. of Radiology, Tokyo Medical and Dental Univ., Tokyo (Japan)], Email: S.Nakaminato@gmail.com; Kawano, Tatsuyuki [Dept. of Surgery, Tokyo Medical and Dental Univ., Tokyo (Japan); Kishimoto, Seiji [Dept. of Head and Neck Surgery, Tokyo Medical and Dental Univ., Tokyo (Japan)

    2012-05-15

    Background. The prevalence of esophageal cancer accompanied by hypopharyngeal cancer (HPC) is high and increasing rapidly in Asia. The purpose of this prospective study was to evaluate the prevalence of esophageal cancer during the pretreatment of HPC patients who were routinely examined using esophagogastroduodenoscopy (EGD) and 18F-fluorodeoxyglucose/computed tomography (FDG-PET/CT) and to discuss the utility of these examinations. Material and methods. Between September 2005 and September 2010, 33 patients with newly diagnosed HPC (all with squamous cell carcinoma) underwent EGD (after a conventional endoscopy, iodine staining was performed) and FDG-PET/CT examinations. We evaluated the prevalence of esophageal cancer among HPC patients according to the EGD findings and determined the sensitivity of FDG-PET/CT for the detection of esophageal primary tumors for each clinical T classification. Results. In 17 of the 33 patients (51.5%), 29 biopsy-proven esophageal squamous cell carcinomas were diagnosed using EGD. In eight of the 17 (47.1%) patients, two or more esophageal cancer lesions were diagnosed. Twenty-four of the 29 (82.8%) lesions were superficial esophageal cancers, and the remaining five (17.2%) lesions were advanced esophageal cancers. In six of the 29 (20.7%) esophageal cancer lesions that were detected using FDG-PET/CT, only one of the 29 (3.4%) lesions was evaluated as being equivocal; the remaining 22 (75.9%) lesions were not detected. The distribution of the clinical T classifications detected using FDG-PET/CT was as follows: T1a, 0/21 (0%); T1b, 1/3 (33%); and T3, 5/5 (100%). Conclusions. The prevalence of esophageal cancer during the pretreatment of HPC patients was 51.5%; this prevalence was higher than that in previous reports. We believe that the increasing proportion of superficial lesions (82.8%) detected using iodine staining and EGD may have led to the relatively high prevalence. FDG-PET/CT detected only 20.7% of the esophageal cancers

  11. Prevalence of esophageal cancer during the pretreatment of hypopharyngeal cancer patients: Routinely performed esophagogastroduodenoscopy and FDG-PET/CT findings

    International Nuclear Information System (INIS)

    Nakaminato, Shuichiro; Toriihara, Akira; Makino, Tomoko; Shibuya, Hitoshi; Kawano, Tatsuyuki; Kishimoto, Seiji

    2012-01-01

    Background. The prevalence of esophageal cancer accompanied by hypopharyngeal cancer (HPC) is high and increasing rapidly in Asia. The purpose of this prospective study was to evaluate the prevalence of esophageal cancer during the pretreatment of HPC patients who were routinely examined using esophagogastroduodenoscopy (EGD) and 18F-fluorodeoxyglucose/computed tomography (FDG-PET/CT) and to discuss the utility of these examinations. Material and methods. Between September 2005 and September 2010, 33 patients with newly diagnosed HPC (all with squamous cell carcinoma) underwent EGD (after a conventional endoscopy, iodine staining was performed) and FDG-PET/CT examinations. We evaluated the prevalence of esophageal cancer among HPC patients according to the EGD findings and determined the sensitivity of FDG-PET/CT for the detection of esophageal primary tumors for each clinical T classification. Results. In 17 of the 33 patients (51.5%), 29 biopsy-proven esophageal squamous cell carcinomas were diagnosed using EGD. In eight of the 17 (47.1%) patients, two or more esophageal cancer lesions were diagnosed. Twenty-four of the 29 (82.8%) lesions were superficial esophageal cancers, and the remaining five (17.2%) lesions were advanced esophageal cancers. In six of the 29 (20.7%) esophageal cancer lesions that were detected using FDG-PET/CT, only one of the 29 (3.4%) lesions was evaluated as being equivocal; the remaining 22 (75.9%) lesions were not detected. The distribution of the clinical T classifications detected using FDG-PET/CT was as follows: T1a, 0/21 (0%); T1b, 1/3 (33%); and T3, 5/5 (100%). Conclusions. The prevalence of esophageal cancer during the pretreatment of HPC patients was 51.5%; this prevalence was higher than that in previous reports. We believe that the increasing proportion of superficial lesions (82.8%) detected using iodine staining and EGD may have led to the relatively high prevalence. FDG-PET/CT detected only 20.7% of the esophageal cancers

  12. The role of spiral CT in patients with intermediate probability V/Q scans: can spiral CT replace pulmonary angiography?

    International Nuclear Information System (INIS)

    Vu, T.; Glenn, D.; Lovett, I.; Moses, J.; Wadhwa, S.S.; Nour, R.

    2000-01-01

    Full text: Spiral CT (SCT) has been advocated as a replacement for pulmonary angiography (PA)in patients with intermediate probability (IP) ventilation-perfusion lung scans (V/Q). More generally it has been proposed as a replacement for V/Q to detect Pulmonary Embolism. This study investigates the accuracy of SCT in the IP patient group 31 patients with IP scans (Modified PIOPED criteria) who were not at high risk of contrast nephrotoxicity were enrolled to have both SCT and PA within the 24 hours following their V/Q. Patients were classified as IP due to a single segmental mismatch (n=7) or a matched V/Q abnormality corresponding to CXR opacity (n=21), or both (n=3). PA is the gold standard for the detection of PE. SCT was read by an experienced radiologist blinded to the PA results. SCT was performed according to standard protocol. All SCT were technically satisfactory for interpretation. Pulmonary embolism was present in 9/31 patients (29%). Of the patients with PE detected by PA, SCT was positive in 4 (44% sensitivity). Of the 22 patients who did not have PE, SCT was negative in 21 and positive in one (96% specificity). In conclusion SCT has limited sensitivity for the detection of PE in patients with IP lung scans. SCT may not be an adequate replacement for PA. Copyright (2000) The Australian and New Zealand Society of Nuclear Medicine Inc

  13. A method for the reconstruction of four-dimensional synchronized CT scans acquired during free breathing

    International Nuclear Information System (INIS)

    Low, Daniel A.; Nystrom, Michelle; Kalinin, Eugene; Parikh, Parag; Dempsey, James F.; Bradley, Jeffrey D.; Mutic, Sasa; Wahab, Sasha H.; Islam, Tareque; Christensen, Gary; Politte, David G.; Whiting, Bruce R.

    2003-01-01

    Breathing motion is a significant source of error in radiotherapy treatment planning for the thorax and upper abdomen. Accounting for breathing motion has a profound effect on the size of conformal radiation portals employed in these sites. Breathing motion also causes artifacts and distortions in treatment planning computed tomography (CT) scans acquired during free breathing and also causes a breakdown of the assumption of the superposition of radiation portals in intensity-modulated radiation therapy, possibly leading to significant dose delivery errors. Proposed voluntary and involuntary breath-hold techniques have the potential for reducing or eliminating the effects of breathing motion, however, they are limited in practice, by the fact that many lung cancer patients cannot tolerate holding their breath. We present an alternative solution to accounting for breathing motion in radiotherapy treatment planning, where multislice CT scans are collected simultaneously with digital spirometry over many free breathing cycles to create a four-dimensional (4-D) image set, where tidal lung volume is the additional dimension. An analysis of this 4-D data leads to methods for digital-spirometry, based elimination or accounting of breathing motion artifacts in radiotherapy treatment planning for free breathing patients. The 4-D image set is generated by sorting free-breathing multislice CT scans according to user-defined tidal-volume bins. A multislice CT scanner is operated in the cine mode, acquiring 15 scans per couch position, while the patient undergoes simultaneous digital-spirometry measurements. The spirometry is used to retrospectively sort the CT scans by their correlated tidal lung volume within the patient's normal breathing cycle. This method has been prototyped using data from three lung cancer patients. The actual tidal lung volumes agreed with the specified bin volumes within standard deviations ranging between 22 and 33 cm 3 . An analysis of sagittal and

  14. 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

  15. 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.

  16. Impact of Pretreatment Noncontrast CT Alberta Stroke Program Early CT Score on Clinical Outcome After Intra-Arterial Stroke Therapy

    NARCIS (Netherlands)

    Yoo, Albert J.; Zaidat, Osama O.; Chaudhry, Zeshan A.; Berkhemer, Olvert A.; González, R. Gilberto; Goyal, Mayank; Demchuk, Andrew M.; Menon, Bijoy K.; Mualem, Elan; Ueda, Dawn; Buell, Hope; Sit, Siu Po; Bose, Arani

    2014-01-01

    The efficacy of intra-arterial treatment remains uncertain. Because most centers performing IAT use noncontrast CT (NCCT) imaging, it is critical to understand the impact of NCCT findings on treatment outcomes. This study aimed to compare functional independence and safety among patients undergoing

  17. Pulmonary nodule registration in serial CT scans based on rib anatomy and nodule template matching

    International Nuclear Information System (INIS)

    Shi Jiazheng; Sahiner, Berkman; Chan, H.-P.; Hadjiiski, Lubomir; Zhou, C.; Cascade, Philip N.; Bogot, Naama; Kazerooni, Ella A.; Wu, Y.-T.; Wei, J.

    2007-01-01

    An automated method is being developed in order to identify corresponding nodules in serial thoracic CT scans for interval change analysis. The method uses the rib centerlines as the reference for initial nodule registration. A spatially adaptive rib segmentation method first locates the regions where the ribs join the spine, which define the starting locations for rib tracking. Each rib is tracked and locally segmented by expectation-maximization. The ribs are automatically labeled, and the centerlines are estimated using skeletonization. For a given nodule in the source scan, the closest three ribs are identified. A three-dimensional (3D) rigid affine transformation guided by simplex optimization aligns the centerlines of each of the three rib pairs in the source and target CT volumes. Automatically defined control points along the centerlines of the three ribs in the source scan and the registered ribs in the target scan are used to guide an initial registration using a second 3D rigid affine transformation. A search volume of interest (VOI) is then located in the target scan. Nodule candidate locations within the search VOI are identified as regions with high Hessian responses. The initial registration is refined by searching for the maximum cross-correlation between the nodule template from the source scan and the candidate locations. The method was evaluated on 48 CT scans from 20 patients. Experienced radiologists identified 101 pairs of corresponding nodules. Three metrics were used for performance evaluation. The first metric was the Euclidean distance between the nodule centers identified by the radiologist and the computer registration, the second metric was a volume overlap measure between the nodule VOIs identified by the radiologist and the computer registration, and the third metric was the hit rate, which measures the fraction of nodules whose centroid computed by the computer registration in the target scan falls within the VOI identified by the

  18. Role of endoscopic ultrasonography in patients with intermediate probability of choledocholithiasis but a negative CT scan.

    Science.gov (United States)

    Kim, Kwang Min; Lee, Jong Kyun; Bahng, Sunha; Shin, Jae Uk; Lee, Kwang Hyuck; Lee, Kyu Taek; Lee, Won Jae; Lim, Jae Hoon

    2013-01-01

    Despite the increased role of endoscopic ultrasonography (EUS) in diagnosis, few studies have evaluated its impact on the management of choledocholithiasis in a clinical setting for patients for whom computed tomography (CT) was conducted initially. Our aim in this study was to evaluate the role of EUS in patients with a diagnosis of intermediate probability of choledocholithiasis with a negative CT scan result. A total of 98 patients who were diagnosed with symptomatic cholelithiasis with intermediate probability of choledocholithiasis were evaluated prospectively. Twenty-six of the 98 patients (26.5%) were diagnosed with choledocholithiasis by CT scans. The remaining 72 patients underwent EUS. Twenty-five of the 72 patients were shown to have choledocholithiasis (n=20/72, 27.8%) or papillitis with biliary outflow obstruction (n=5/72, 6.9%) on EUS. These 25 patients with positive EUS findings underwent endoscopic sphincterotomy, and choledocholithiasis was endoscopically confirmed in 23 of the 25 patients (92.0%). Postendoscopic retrograde cholangiopancreatography (ERCP) pancreatitis occurred in 3 patients (12.0% of the 25 patients who received ERCP, 4.2% of all 72 patients). Forty-seven patients with no evidence of choledocholithiasis on EUS were followed-up for a median period of 340 days (range, 185 to 755 d), and no recurrent biliary events occurred in these patients during this period. The sensitivity and specificity of EUS for choledocholithiasis was 87.0% and 100%, respectively. An EUS-first strategy in patients with intermediate probability of choledocholithiasis but a negative CT scan is very useful and can reduce the need to perform invasive ERCP.

  19. Radiology resident evaluation of head CT scan orders in the emergency department.

    Science.gov (United States)

    Erly, William K; Berger, William G; Krupinski, Elizabeth; Seeger, Joachim F; Guisto, John A

    2002-01-01

    Prior studies have revealed little difference in residents' abilities to interpret cranial CT scans. The purpose of this study was to assess the performance of radiology residents at different levels of training in the interpretation of emergency head CT images. Radiology residents prospectively interpreted 1324 consecutive head CT scans ordered in the emergency department at the University of Arizona Health Science Center. The residents completed a preliminary interpretation form that included their interpretation and confidence in that interpretation. One of five neuroradiologists with a Certificate of Added Qualification subsequently interpreted the images and classified their assessment of the residents' interpretations as follows: "agree," "disagree-insignificant," or "disagree-significant." The data were analyzed by using analysis-of-variance or chi-squared methods. Overall, the agreement rate was 91%; the insignificant disagreement rate, 7%; and the significant disagreement rate, 2%. The level of training had a significant (P =.032) effect on the rate of agreement; upper-level residents had higher rates of agreement than those of more junior residents. There were 62 false-negative findings. The most commonly missed findings were fractures (n = 18) and chronic ischemic foci (n = 12). The most common false-positive interpretations involved 10 suspected intracranial hemorrhages and suspected fractures. The level of resident training has a significant effect on the rate of disagreement between the preliminary interpretations of emergency cranial CT scans by residents and the final interpretations by neuroradiologists. Efforts to reduce residents' errors should focus on the identification of fractures and signs of chronic ischemic change.

  20. 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

  1. A measurement-based generalized source model for Monte Carlo dose simulations of CT scans.

    Science.gov (United States)

    Ming, Xin; Feng, Yuanming; Liu, Ransheng; Yang, Chengwen; Zhou, Li; Zhai, Hezheng; Deng, Jun

    2017-03-07

    The goal of this study is to develop a generalized source model for accurate Monte Carlo dose simulations of CT scans based solely on the measurement data without a priori knowledge of scanner specifications. The proposed generalized source model consists of an extended circular source located at x-ray target level with its energy spectrum, source distribution and fluence distribution derived from a set of measurement data conveniently available in the clinic. Specifically, the central axis percent depth dose (PDD) curves measured in water and the cone output factors measured in air were used to derive the energy spectrum and the source distribution respectively with a Levenberg-Marquardt algorithm. The in-air film measurement of fan-beam dose profiles at fixed gantry was back-projected to generate the fluence distribution of the source model. A benchmarked Monte Carlo user code was used to simulate the dose distributions in water with the developed source model as beam input. The feasibility and accuracy of the proposed source model was tested on a GE LightSpeed and a Philips Brilliance Big Bore multi-detector CT (MDCT) scanners available in our clinic. In general, the Monte Carlo simulations of the PDDs in water and dose profiles along lateral and longitudinal directions agreed with the measurements within 4%/1 mm for both CT scanners. The absolute dose comparison using two CTDI phantoms (16 cm and 32 cm in diameters) indicated a better than 5% agreement between the Monte Carlo-simulated and the ion chamber-measured doses at a variety of locations for the two scanners. Overall, this study demonstrated that a generalized source model can be constructed based only on a set of measurement data and used for accurate Monte Carlo dose simulations of patients' CT scans, which would facilitate patient-specific CT organ dose estimation and cancer risk management in the diagnostic and therapeutic radiology.

  2. Open source deformable image registration system for treatment planning and recurrence CT scans. Validation in the head and neck region

    International Nuclear Information System (INIS)

    Zukauskaite, Ruta; Brink, Carsten; Hansen, Christian Roenn; Bertelsen, Anders; Johansen, Joergen; Eriksen, Jesper Grau; Grau, Cai

    2016-01-01

    Clinical application of deformable registration (DIR) of medical images remains limited due to sparse validation of DIR methods in specific situations, e. g. in case of cancer recurrences. In this study the accuracy of DIR for registration of planning CT (pCT) and recurrence CT (rCT) images of head and neck squamous cell carcinoma (HNSCC) patients was evaluated. 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 manually contoured eight anatomical regions-of-interest (ROI) twice on pCT and once on rCT. pCT and rCT images were deformably registered using the open source software elastix. Mean surface distance (MSD) and Dice similarity coefficient (DSC) between contours were used for validation of DIR. A measure for delineation uncertainty was estimated by assessing MSD from the re-delineations of the same ROI on pCT. DIR and manual contouring uncertainties were correlated with tissue volume and rigidity. MSD varied 1-3 mm for different ROIs for DIR and 1-1.5 mm for re-delineated ROIs performed 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 < 0.001) and tissue rigidity (r = 0.54, p < 0.001). DIR using elastix in HNSCC on planning and recurrence CT scans is feasible; an uncertainty of the method is close to the voxel size length of the planning CT images. (orig.) [de

  3. 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

  4. 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.

  5. Clinical neurological, electrophysiological, and cerebral CT scan findings in systemic lupus erythematosus.

    Science.gov (United States)

    Omdal, R; Selseth, B; Kløw, N E; Husby, G; Mellgren, S I

    1989-01-01

    Thirty SLE patients underwent clinical neurological examination, electrophysiological studies, cerebral computer tomographic (CT) scans, and blood sampling. Nineteen patients (63%) had clinical neuropsychiatric and 10 patients (33%) had clinical neuromuscular manifestations. Migrainous headache affecting 11 patients (37%) was the most prevalent clinical manifestation. Electrophysiological testing revealed abnormal electroencephalography in 10 patients (33%). Abnormal electromyography and nerve conduction velocity were found in 13 (43%) and 7 (24%) patients respectively. Abnormal visual evoked response was detected in 2 patients. Cerebral CT scans displayed cerebral atrophy in 20 patients (71%), while 6 patients (21%) had cerebral infractions. Disease activity assessed by two different tests revealed a higher prevalence of cerebral infarctions, classical migraine, muscular weakness, and pathological electromyography and nerve conduction velocity in the higher disease activity groups. Cerebral infarctions were only found among anti-Ro negative patients, but apart from this, no significant association could be found between coagulopathy, circulating immune complexes, cryoglobulins, routine immunological tests, medication, and any clinical, electrophysiological or cerebral CT pathology.

  6. Comparison of MRI and X-ray CT scan findings in serious head injury

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Yoshikazu; Shima, Takeshi; Nishida, Masahiro (Chugoku Rosai Hospital, Hiroshima (Japan)) (and others)

    1991-08-01

    Twenty one patients with serious neurological deficits, prolonged consciousness disturbance and three months follow-up periods were examined by MRI at the acute to chronic stage, which were compared with X-ray CT findings. Sixteen patients' glasgow coma scale (GCS) on admission was less than 7, and five patients' GCS was more than 8. X-ray CT scan revealed diffuse brain contusion and/or hematoma in 14 patients, deep structural lesions in two patients and no lesion in five patients. MRI demonstrated cerebral contusion in 11 patients, deep structural lesions with or without cerebral contusion in 10 patients and no lesion in two patients. The deep structural lesions correlated with prolonged consciousness disturbance and serious neurological deficits, but did not closely related with clinical outcomes. These results indicated that X-ray CT scan was very effective for detecting the intracranial hemorrhagic lesions in the acute stage, but MRI was recommended for documenting brain lesions at the deep structures and evaluating the clinical outcomes in the chronic stage. (author).

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

    International Nuclear Information System (INIS)

    Park, M; Rosica, D; Agarwal, V; Di Carli, M; Dorbala, S

    2016-01-01

    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 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. 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.

  9. Influence of PET/CT-introduction on PET scanning frequency and indications. Results of a multicenter study

    International Nuclear Information System (INIS)

    Stergar, H.; Bockisch, A.; Eschmann, S.M.; Krause, B.J.; Roedel, R.; Tiling, R.; Weckesser, M.

    2007-01-01

    Aim: to evaluate the influence of the introduction of combined PET/CT scanners into clinical routine. This investigation addresses the quantitative changes between PET/CT and stand alone PET. Methods: the study included all examinations performed on stand alone PET- or PET/CT-scanners within 12 month prior to and after implementation of PET/CT. The final data analysis included five university hospitals and a total number of 15 497 exams. We distinguished exams on stand alone tomographs prior to and after installation of the combined device as well as PET/CT scans particularly with regard to disease entities. Various further parameters were investigated. Results: the overall number of PET scans (PET and PET/CT) rose by 146% while the number of scans performed on stand alone scanners declined by 22%. Only one site registered an increase in stand alone PET. The number of exams for staging in oncology increased by 196% while that of cardiac scans decreased by 35% and the number of scans in neurology rose by 47%. The use of scans for radiotherapy planning increased to 7% of all PET/CT studies. The increase of procedures for so-called classic PET oncology indications was moderate compared to the more common tumors. An even greater increase was observed in some rare entities. Conclusions: the introduction of PET/CT led to more than a doubling of overall PET procedures with a main focus on oncology. Some of the observed changes in scanning frequency may be caused by a rising availability of new radiotracers and advancements of competing imaging methods. Nevertheless the evident increase in the use of PET/CT for the most common tumour types demonstrates its expanding role in cancer staging. The combination of molecular and morphologic imaging has not only found its place but is still gaining greater importance with new developments in technology and radiochemistry. (orig.)

  10. Autopsy Findings of Brainstem in Head Trauma in Comparison with CT Scan Findings in Brain Trauma Ward in Tabriz, Iran

    OpenAIRE

    Shakeri Bavil Moslem; Ashrafian Fereydun; Daghighi Mohammad Ali; Samadi Rad Bahram; Zeinali Ali

    2009-01-01

    Computed tomography (CT) is now the primary diagnostic method for head trauma because of its ability to demonstrate the nature, extent, sites, and multiplicity of brain injuries. Although there have been numerous reports on the CT findings of most types of intracranial injury, the findings in brainstem injury have not been well described. This study aimed at comparing the autopsy findings of brainstem in head trauma in comparison with CT scan results. Two hundred patients with head trauma, wh...

  11. BODY SIZE-SPECIFIC EFFECTIVE DOSE CONVERSION COEFFICIENTS FOR CT SCANS.

    Science.gov (United States)

    Romanyukha, Anna; Folio, Les; Lamart, Stephanie; Simon, Steven L; Lee, Choonsik

    2016-12-01

    Effective dose from computed tomography (CT) examinations is usually estimated using the scanner-provided dose-length product and using conversion factors, also known as k-factors, which correspond to scan regions and differ by age according to five categories: 0, 1, 5, 10 y and adult. However, patients often deviate from the standard body size on which the conversion factor is based. In this study, a method for deriving body size-specific k-factors is presented, which can be determined from a simple regression curve based on patient diameter at the centre of the scan range. Using the International Commission on Radiological Protection reference paediatric and adult computational phantoms paired with Monte Carlo simulation of CT X-ray beams, the authors derived a regression-based k-factor model for the following CT scan types: head-neck, head, neck, chest, abdomen, pelvis, abdomen-pelvis (AP) and chest-abdomen-pelvis (CAP). The resulting regression functions were applied to a total of 105 paediatric and 279 adult CT scans randomly sampled from patients who underwent chest, AP and CAP scans at the National Institutes of Health Clinical Center. The authors have calculated and compared the effective doses derived from the conventional age-specific k-factors with the values computed using their body size-specific k-factor. They found that by using the age-specific k-factor, paediatric patients tend to have underestimates (up to 3-fold) of effective dose, while underweight and overweight adult patients tend to have underestimates (up to 2.6-fold) and overestimates (up to 4.6-fold) of effective dose, respectively, compared with the effective dose determined from their body size-dependent factors. The authors present these size-specific k-factors as an alternative to the existing age-specific factors. The body size-specific k-factor will assess effective dose more precisely and on a more individual level than the conventional age-specific k-factors and, hence, improve

  12. The evaluation of radioprotection with low dose CT scanning in normal rabbits brain

    International Nuclear Information System (INIS)

    Zhang Shuqing; Gong Shenchu; Wang Tianle; Shen Yunxia; Cui Lei

    2008-01-01

    Objective: To determine wheather a lower radiation dose technique and various pitch could be used in CT of the rabbits' brain without jeopardizing the diagnostic accuracy of the images, and determine the evaluation of radioprotection with low dose CT scanning. Methods: Fifteen rabbits underwent CT using 200 mAs, 110 mAs or 70 mAs,and pitch 1.0 or 1.5. Anatomy details and the confidence level in reaching a diagnosis were evaluated by two radiologists in a double-blinded manner using a 4-point scoring system. The CTDI w of every group were compared. Results: For both reader there was no statistically significant difference between 6 group total score of 1-6 anatomical detail and each of 6 anatomical detail although score for each of 6 anatomical detail. The CTDI w of 70 mAs, in pitch 1.5 group decreased about 76.7%. Conclusion: Radiation dose reduction in brain CT is feasible in clinical use, and quality of images can be re- served. It plays an important role in radiation protection. (authors)

  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...... of this study is to minimise the scan time of the CBCT without compromising the accuracy of the image registration in IGRT....

  14. A Survey of Pediatric CT Protocols and Radiation Doses in South Korean Hospitals to Optimize the Radiation Dose for Pediatric CT Scanning

    Science.gov (United States)

    Hwang, Jae-Yeon; Do, Kyung-Hyun; Yang, Dong Hyun; Cho, Young Ah; Yoon, Hye-Kyung; Lee, Jin Seong; Koo, Hyun Jung

    2015-01-01

    Abstract Children are at greater risk of radiation exposure than adults because the rapidly dividing cells of children tend to be more radiosensitive and they have a longer expected life time in which to develop potential radiation injury. Some studies have surveyed computed tomography (CT) radiation doses and several studies have established diagnostic reference levels according to patient age or body size; however, no survey of CT radiation doses with a large number of patients has yet been carried out in South Korea. The aim of the present study was to investigate the radiation dose in pediatric CT examinations performed throughout South Korea. From 512 CT (222 brain CT, 105 chest CT, and 185 abdominopelvic CT) scans that were referred to our tertiary hospital, a dose report sheet was available for retrospective analysis of CT scan protocols and dose, including the volumetric CT dose index (CTDIvol), dose-length product (DLP), effective dose, and size-specific dose estimates (SSDE). At 55.2%, multiphase CT was the most frequently performed protocol for abdominopelvic CT. Tube current modulation was applied most often in abdominopelvic CT and chest CT, accounting for 70.1% and 62.7%, respectively. Regarding the CT dose, the interquartile ranges of the CTDIvol were 11.1 to 22.5 (newborns), 16.6 to 39.1 (≤1 year), 14.6 to 41.7 (2–5 years), 23.5 to 44.1 (6–10 years), and 31.4 to 55.3 (≤15 years) for brain CT; 1.3 to 5.7 (≤1 year), 3.9 to 6.8 (2–5 years), 3.9 to 9.3 (6–10 years), and 7.7 to 13.8 (≤15 years) for chest CT; and 4.0 to 7.5 (≤1 year), 4.2 to 8.9 (2–5 years), 5.7 to 12.4 (6–10 years), and 7.6 to 16.6 (≤15 years) for abdominopelvic CT. The SSDE and CTDIvol were well correlated for patients CT in South Korea. The CTDIvol, DLP, and effective dose were generally lower than in German and UK surveys, except in certain age groups. PMID:26683922

  15. Self-directed learning modules of CT scan images to improve students' perception of gross anatomy.

    Science.gov (United States)

    Kumar, Pananghat Achutha; Jothi, Ramakrishnan; Mathivanan, Dharmalingam

    2016-01-01

    A contemporary anatomy curriculum that aims to be clinically relevant requires medical students to be introduced to radiological anatomy in the preclinical years. Ideally, the curriculum should also support self-directed learning, a habit best instilled early. Based on these educational requirements, we designed an interesting and clinically-meaningful program of self-learning modules in radiological anatomy to augment students' learning of gross anatomy. The program is guided by current theories of learning, which emphasize an individualized learning pace for students. This program uses enlarged computerized tomography (CT) scan images and associated resource materials. Scans are posted on the first day of the week in a public area for students to review on their own time. On the second day penciled outlines of important structures are provided to help students identify structures, and students are encouraged to discuss the images with faculty. On the last day of the week the identity of the structures are revealed to students. An open-ended questionnaire used to evaluate the program revealed that 95.5% of students used the program and a great majority recommended the program should be continued for future students. The present program enhances learning of gross anatomical relations through having students use visual clues in logically interpreting unlabeled CT scans in an organized and sequential way. The program promotes self-directed learning. In addition to its use with preclinical students, the modules might also help students in the clinical phase of the curriculum bolster their knowledge of spatial anatomy.

  16. Initial experience with optical-CT scanning of RadBall Dosimeters

    International Nuclear Information System (INIS)

    Oldham, M; Clift, C; Thomas, A; Farfan, E; Foley, T; Jannik, T; Adamovics, J; Holmes, C; Stanley, S

    2010-01-01

    The RadBall dosimeter is a novel device for providing 3-D information on the magnitude and distribution of contaminant sources of unknown radiation in a given hot cell, glovebox, or contaminated room. The device is presently under evaluation by the National Nuclear Lab (NNL, UK) and the Savannah River National Laboratory (SRNL, US), for application as a diagnostic device for such unknown contaminants in the nuclear industry. A critical component of the technique is imaging the dose distribution recorded in the RadBall using optical-CT scanning. Here we present our initial investigations using the Duke Mid-sized Optical-CT Scanner (DMOS) to image dose distributions deposited in RadBalls exposed to a variety of radiation treatments.

  17. 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.

  18. CT scan diagnosis of hepatic adenoma in a case of von Gierke disease

    International Nuclear Information System (INIS)

    Daga, Bipin Valchandji; Shah, Vaibhav R; More, Rahul B

    2012-01-01

    Hepatic adenoma is a well-defined, benign, solitary tumor of the liver. In individuals with glycogen storage disease I, adenoma tends to occur at a relatively younger age and can be multiple (adenomatosis). Imaging plays a pivotal role in diagnosing hepatic adenoma and in differentiating adenoma from other focal hepatic lesions. Especially in patients with von Gierke disease, in addition to the associated hepatomegaly caused by steatohepatitis and the diffusely reduced attenuation of the liver parenchyma seen on CT, there may be more than one hepatic adenoma in up to 40% of patients. Malignant degeneration of hepatic adenoma into hepatocellular carcinoma can occur and hence imaging is important for prompt diagnosis of adenoma and its complications. In this case report, we present a case of liver adenoma diagnosed by CT scan in a patient with von Gierke disease

  19. CT scan diagnosis of hepatic adenoma in a case of von Gierke disease

    Directory of Open Access Journals (Sweden)

    Bipin Valchandji Daga

    2012-01-01

    Full Text Available Hepatic adenoma is a well-defined, benign, solitary tumor of the liver. In individuals with glycogen storage disease I, adenoma tends to occur at a relatively younger age and can be multiple (adenomatosis. Imaging plays a pivotal role in diagnosing hepatic adenoma and in differentiating adenoma from other focal hepatic lesions. Especially in patients with von Gierke disease, in addition to the associated hepatomegaly caused by steatohepatitis and the diffusely reduced attenuation of the liver parenchyma seen on CT, there may be more than one hepatic adenoma in up to 40% of patients. Malignant degeneration of hepatic adenoma into hepatocellular carcinoma can occur and hence imaging is important for prompt diagnosis of adenoma and its complications. In this case report, we present a case of liver adenoma diagnosed by CT scan in a patient with von Gierke disease.

  20. CT scan diagnosis of hepatic adenoma in a case of von Gierke disease.

    Science.gov (United States)

    Daga, Bipin Valchandji; Shah, Vaibhav R; More, Rahul B

    2012-01-01

    Hepatic adenoma is a well-defined, benign, solitary tumor of the liver. In individuals with glycogen storage disease I, adenoma tends to occur at a relatively younger age and can be multiple (adenomatosis). Imaging plays a pivotal role in diagnosing hepatic adenoma and in differentiating adenoma from other focal hepatic lesions. Especially in patients with von Gierke disease, in addition to the associated hepatomegaly caused by steatohepatitis and the diffusely reduced attenuation of the liver parenchyma seen on CT, there may be more than one hepatic adenoma in up to 40% of patients. Malignant degeneration of hepatic adenoma into hepatocellular carcinoma can occur and hence imaging is important for prompt diagnosis of adenoma and its complications. In this case report, we present a case of liver adenoma diagnosed by CT scan in a patient with von Gierke disease.

  1. 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.

  2. 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

  3. 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.

  4. Using Micro CT Scanning to Assess Pteropod Shells in the Modern Ocean

    Science.gov (United States)

    Oakes, R. L.; Urbanski, J. M.; Bralower, T. J.

    2016-02-01

    Anthropogenic activities are causing fundamental changes to ocean chemistry. Calcareous plankton and nekton are predicted to be affected by these chemical changes, especially by ocean acidification. These groups are at the base of the marine food chain and therefore their demise will have a strong effect on the marine ecosystem as a whole. One challenge moving forward is to find a method to assess how chemical changes manifest themselves in plankton and nekton shells. Recent advancements in computed tomographic (CT) scanning technology allows for organisms to be imaged in three dimensions at micrometer resolution. CT data enables quantitative measurements of properties such as shell thickness, volume, and morphology. We apply this method to look at pteropods, nektonic molluscs which make their shells from the more soluble form of calcium carbonate, aragonite. Their shell mineralogy, and the fact that some groups live in polar and upwelling waters, place them at high risk for ocean acidification. We have scanned over 70 pteropods from 5 different locations globally. Analysis shows that there is a significant difference in pteropod shell thickness in different ocean basins with the thinnest shells being found off the coast of Washington. Changes in shell thickness may affect pteropod swimming efficiency, predation, and rate of sinking. Shell volume does not seem to vary with shell thickness suggesting that changes will impact pteropods at all ontogenetic stages. We are working towards a geometric morphometric analysis of these shells to see if the shape differs in areas with different ocean conditions. This initial set of CT scans of pteropods can be used as a baseline to which future changes can be compared. Furthermore, this technique has the potential to be easily transferred to other organisms as a method of assessing shell change in response to ocean acidification and associated factors.

  5. A case of intracranial malignant lymphoma with pure akinesia and repeated regression on CT scans

    International Nuclear Information System (INIS)

    Suzuki, Takeo; Yamamoto, Mari; Saitoh, Mitsunori; Aoki, Akira; Imai, Hisamasa; Narabayashi, Hirotaro.

    1984-01-01

    In a case of primary reticulum cell sarcoma in the brain, histologically verified by biopsy, the tumor regressed twice on a CT scan without radiotherapy. The systemic freezing phenomenon was seen as a main clinical symptom. The patient, a 44 year-old male, first complained of decreased livido and festinating speech. He also showed frozen gait, micrographia, a decrease in spontaneity and urinary incontinence. Four months after onset he was hospitalized. Neurological findings on admission revealed freezing of gait, writing, and speech, but there was no weakness of muscles with normal tendon reflexes, and normal muscular tone. In the CT scan on admission, there were high density areas mainly in the head of the right caudate nucleus, the medial deep portion of the right frontal lobe, the right side of the hypothalamus, the anterior thalamus, the globus pallidus. There were also nodular-type enhanced effects in the same areas. Regression of the tumor was seen on the CT scans after administration of betamethasone. The tumor which had again incrased in size regressed spontaneously without the use of steroids after 3 months. Thereafter, the tumor gradually became larger and an open biopsy was perfomed. Histopathological findings showed a reticulum cell sarcoma. There were no findings of systemic malignant lymphoma. Such intracrainal malignant lymphomas showing repeated regression including spontaneous one are very rare in the literature. The freezing phenomenon in this case started with festinating speech and spread to writing and gait. L-DOPA had no effect. This systemic freezing phenomenon was considered to be the same as that in the cases of pure akinesia without rigidity and tremor reported by Narabayashi and Imai, which did not respond to L-DOPA at all. But on the other hand, L-Threo-3, 4-Dihydroxyphenylserine was effective to the frozen gait of this patient. (J.P.N.)

  6. Development of automated quantification of visceral and subcutaneous adipose tissue volumes from abdominal CT scans

    Science.gov (United States)

    Mensink, Sanne D.; Spliethoff, Jarich W.; Belder, Ruben; Klaase, Joost M.; Bezooijen, Roland; Slump, Cornelis H.

    2011-03-01

    This contribution describes a novel algorithm for the automated quantification of visceral and subcutaneous adipose tissue volumes from abdominal CT scans of patients referred for colorectal resection. Visceral and subcutaneous adipose tissue volumes can accurately be measured with errors of 1.2 and 0.5%, respectively. Also the reproducibility of CT measurements is good; a disadvantage is the amount of radiation. In this study the diagnostic CT scans in the work - up of (colorectal) cancer were used. This implied no extra radiation. For the purpose of segmentation alone, a low dose protocol can be applied. Obesity is a well known risk factor for complications in and after surgery. Body Mass Index (BMI) is a widely accepted indicator of obesity, but it is not specific for risk assessment of colorectal surgery. We report on an automated method to quantify visceral and subcutaneous adipose tissue volumes as a basic step in a clinical research project concerning preoperative risk assessment. The outcomes are to be correlated with the surgery results. The hypothesis is that the balance between visceral and subcutaneous adipose tissue together with the presence of calcifications in the major bloodvessels, is a predictive indicator for post - operatieve complications such as anastomotic leak. We start with four different computer simulated humanoid abdominal volumes with tissue values in the appropriate Hounsfield range at different dose levels. With satisfactory numerical results for this test, we have applied the algorithm on over a 100 patient scans and have compared results with manual segmentations by an expert for a smaller pilot group. The results are within a 5% difference. Compared to other studies reported in the literature, reliable values are obtained for visceral and subcutaneous adipose tissue areas.

  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. 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.

  9. CT scan and histological findings in experimental cerebral infarctions in cats

    International Nuclear Information System (INIS)

    Morimoto, Tetsuya

    1981-01-01

    Experimental cerebral infarctions were made in sixty-five cats by the transorbital approach. CT scanning was done at various periods after right-middle cerebral artery occlusion, and all cases were studied histopathologically. Cerebral microcirculation was studied by the carbon perfusion method, and blood-brain barrier (BBB) dysfunction was studied by intravenous fluorescein administration. The iodine content of brain tissue was measured and this value was compared with the findings on CT scan. Experimental cerebral infarction was divided into four stages according to CT scan findings. These are the pre-edema stage, edema stage, edema diminishing stage, and cavity stage. The low density area (LDA) in the edema stage has a mass effect and a spongy appearance is seen histopathologically. LDA in the edema diminishing stage is localized to the extent of the macroscopic infarcted region, and macrophage (so called ''gitter cells'') and capillaries are seen. Fluorescein stain indicating the area of BBB dysfunction shows almost the same extent as the area of disturbed microcirculation indicated by impaired carbon filling. In the edema diminishing stage, there is good carbon filling in the infarcted region, and enlarged capillaries with carbon black inside are seen. The study of iodine content showed that the iodine level is very high in the infarcted region, and the level has good correlation with the number of capillaries. The mechanism of contrast enhancement in the cerebral infarction seems to be well linked to the capillaries with BBB dysfunction. This study indicates that the contrast medium leaks through the capillary wall. (author)

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

    International Nuclear Information System (INIS)

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

    1987-01-01

    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 [fr

  11. Colonic volvulus detected by CT scan in a case with mental retardation and prune belly syndrome.

    Science.gov (United States)

    Oka, Yoichiro; Masumoto, Kouji; Nakamura, Masatoshi; Iwasaki, Akinori

    2011-10-01

    Colonic volvulus is a rare disease in children. Delayed diagnosis of the condition can often be fatal, especially in pediatric patients with mental retardation. We herein present the case of a female pediatric patient with colonic volvulus, prune belly syndrome, and mental retardation. Preoperative CT scans showed the characteristic signs of this disease. The volvulus occurred in the proximal colon of the colostomy. The release of the colonic volvulus and reconstruction of the colostomy were performed without the resection of the ischemic colon. The postoperative clinical course was uneventful. Copyright © 2012. Published by Elsevier B.V.

  12. Colonic volvulus detected by CT scan in a case with mental retardation and prune belly syndrome

    Directory of Open Access Journals (Sweden)

    Yoichiro Oka

    2011-10-01

    Full Text Available Colonic volvulus is a rare disease in children. Delayed diagnosis of the condition can often be fatal, especially in pediatric patients with mental retardation. We herein present the case of a female pediatric patient with colonic volvulus, prune belly syndrome, and mental retardation. Preoperative CT scans showed the characteristic signs of this disease. The volvulus occurred in the proximal colon of the colostomy. The release of the colonic volvulus and reconstruction of the colostomy were performed without the resection of the ischemic colon. The postoperative clinical course was uneventful.

  13. Hubungan Antara Lama Pembacaan Ct Scan Terhadap Outcome Penderita Stroke Non Hemoragik

    OpenAIRE

    Prakasita, Masayu; Tugasworo, Dodik; Ismail, Akhmad

    2015-01-01

    Background : Stroke is world's health problem that can leads into death and disability. Stroke is one of emergency case because it can threatening life so that it needs an urgent intervention with an accurate and fast diagnosis using non-contrast CT Scan as gold standart. Faster the diagnosis is made then faster the intervention is given, so the outcome of non-hemorrhagic stroke patients which is measured by Barthel Index are better.Methods : This study is an observational analytic study with...

  14. Combined diagnosis of lateral cervical masses by RI-scintigraphy, ultrasound and CT-scanning

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Kuang-Tsuong; Yamashita, Toshio; Sasa, Hidehiko

    1984-09-01

    Careful palpation, plain X-rays and angiography are useful in the diagnosis of lateral cervical masses, but accurate preoperative evaluation sometimes needs further examinations. Recently several new auxiliary procedures have become available such as RI-scintigraphy, Ultrasound, and CT-scanning but even these may not be sufficient when used singly. When all these procedures were combined preoperatively in the case of lateral cervical masses and the results were compared with the findings at time of surgery and the pathology of the extirpated masses, acurate preoperative diagnose were possible.

  15. [Clinical application of computer assisted technology based spiral CT scan for locating impacted tooth].

    Science.gov (United States)

    Zhang, Xing; Zhang, Jie-mei; Chen, Song-ling; Chen, Jian-ling

    2009-10-01

    To evaluate clinical value of computer assisted technology for locating the impacted tooth. Thirty-five patients with impacted tooth were received spiral CT scan. The DICOM data were processed by Simplant software for locating the impacted tooth. The reconstruction images clearly showed detail of the impacted teeth, including 3D surface image, eruption orientation, buccal and lingual location, medial and distal location and relationship with dentition and circumambient anatomic structure. The computer assisted technology can localize the impacted tooth precisely and provide valuable information for clinical treatment.

  16. Application of low-dose radiation protocols in survey CT scans

    International Nuclear Information System (INIS)

    Fu Qiang; Liu Ting; Lu Tao; Xu Ke; Zhang Lin

    2009-01-01

    Objective: To characterize the protocols with low-dose radiation in survey CT scans for localization. Methods: Eighty standard adult patients, head and body phantoms were recruited. Default protocols provided by operator's manual setting were that all the tube voltage for head, chest, abdomen and lumbar was 120 kV; the tube currents were 20,10,20 and 40 mA, respectively. Values of kV and mA in the low-dose experiments were optimized according to the device options. For chest and abdomen, the tube position were compared between default (0 degree) and 180 degree. Phantoms were scanned with above protocols, and the radiation doses were measured respectively. Paired t-test were used for comparisons of standard deviation in CT value, noise and exposure surface dose (ESD) between group with default protocols and group with optimized protocols. Results: The optimized protocols in low-dose CT survey scans were 80 kV, 10 mA for head, 80 kV, 10 mA for chest, 80 kV, 10 mA for abdomen and 100 kV, 10 mA for lumbar. The values of ESD for phantom scan in default and optimized protocols were 0.38 mGy/0.16 mGy in head, 0.30 mGy/0.20 mGy in chest, 0.74 mGy/0.30 mGy in abdomen and 0.81 mGy/0.44 mGy in lumbar, respectively. Compared with default protocols, the optimized protocols reduced the radiation doses 59%, 33%, 59% and 46% in head, chest, abdomen and lumbar. When tube position changed from 0 degree to 180 degree, the ESD were 0.24 mGy/0.20 mGy for chest; 0.37 mGy/0.30 mGy for abdomen, and the radiation doses were reduced 20% and 17%. Conclusion: A certain amount of image noise is increased in low-dose protocols, but image quality is still acceptable without problem in CT localization. The reduction of radiation dose and the radiation harm to patients are the superiority. (authors)

  17. Automated detection and volumetric segmentation of the spleen in CT scans

    International Nuclear Information System (INIS)

    Hammon, M.; Dankerl, P.; Janka, R.; Uder, M.; Cavallaro, A.; Kramer, M.; Seifert, S.; Tsymbal, A.; Costa, M.J.

    2012-01-01

    To introduce automated detection and volumetric segmentation of the spleen in spiral CT scans with the THESEUS-MEDICO software. The consistency between automated volumetry (aV), estimated volume determination (eV) and manual volume segmentation (mV) was evaluated. Retrospective evaluation of the CAD system based on methods like ''marginal space learning'' and ''boosting algorithms''. 3 consecutive spiral CT scans (thoraco-abdominal; portal-venous contrast agent phase; 1 or 5 mm slice thickness) of 15 consecutive lymphoma patients were included. The eV: 30 cm 3 + 0.58 (width x length x thickness of the spleen) and the mV as the reference standard were determined by an experienced radiologist. The aV could be performed in all CT scans within 15.2 (± 2.4) seconds. The average splenic volume measured by aV was 268.21 ± 114.67 cm 3 compared to 281.58 ± 130.21 cm 3 in mV and 268.93 ± 104.60 cm 3 in eV. The correlation coefficient was 0.99 (coefficient of determination (R 2 ) = 0.98) for aV and mV, 0.91 (R 2 = 0.83) for mV and eV and 0.91 (R 2 = 0.82) for aV and eV. There was an almost perfect correlation of the changes in splenic volume measured with the new aV and mV (0.92; R 2 = 0.84), mV and eV (0.95; R 2 = 0.91) and aV and eV (0.83; R 2 = 0.69) between two time points. The automated detection and volumetric segmentation software rapidly provides an accurate measurement of the splenic volume in CT scans. Knowledge about splenic volume and its change between two examinations provides valuable clinical information without effort for the radiologist. (orig.)

  18. 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...

  19. 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.

  20. 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

  1. 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

  2. Autopsy Findings of Brainstem in Head Trauma in Comparison with CT Scan Findings in Brain Trauma Ward in Tabriz, Iran

    Directory of Open Access Journals (Sweden)

    Shakeri Bavil Moslem

    2009-10-01

    Full Text Available Computed tomography (CT is now the primary diagnostic method for head trauma because of its ability to demonstrate the nature, extent, sites, and multiplicity of brain injuries. Although there have been numerous reports on the CT findings of most types of intracranial injury, the findings in brainstem injury have not been well described. This study aimed at comparing the autopsy findings of brainstem in head trauma in comparison with CT scan results. Two hundred patients with head trauma, who expired after a period of time of hospitalization, were assessed in a diagnostic value study. Brain stem involvement was determined by autopsy as well as CT scanning of the brain during their hospitalization. The results of the two methods were compared with each other, emphasizing on the type and location of probable lesions in the brain stem. Considering the autopsy as the method of the choice, sensitivity, specificity, positive predictive value (PPV and negative predictive value (NPV of CT scan in brain stem lesions of patients with head trauma were calculated. The effect of primary cause of head trauma, survival time and Glasgow Coma Scale (GCS were evaluated, as well. Brain stem lesions were detected in 39 (19.5% patients in autopsy. However, CT scan revealed brain stem lesions in 23(11.5% cases. The sensitivity, specificity, PPV and NPV of CT scan was 59%, 100%, 100% and 91% respectively. The most common lesions of the brain stem region were as contusion of pons (8.5%, medulla (5% and midbrain (4.5%. There were 6 (3% cases of ponto-medullary junction tearing and 1 (0.5% case of cervico-medullary junction tearing. CT scan is a specific method of evaluating patients with probable brain stem injuries after head trauma, but low sensitivity limits its efficacy. Our results are in conformity with the reports in the literature.

  3. Methodology for converting CT medical images to MCNP input using the Scan2MCNP system

    International Nuclear Information System (INIS)

    Boia, L.S.; Silva, A.X.; Cardoso, S.C.; Castro, R.C.

    2009-01-01

    This paper develops a methodology for the application software Scan2MCNP, which converts medical images DICOM (Digital Imaging and Communications in Medicine) for MCNP input file. The Scan2MCNP handles, processes and executes the medical images generated by CT equipment, allowing the user to perform the selection and parameterization of the study area in question (tissues and organs). The details of these worked in medical imaging software, therefore, will be converted to equity to the process of language analysis of MCNP radiation transport, through the generation of a code input file. With this file, it is possible to simulate any situation/problem of the type and level of radiation to the proposed treatment chosen by the medical staff responsible for the patient. Within a computational process oriented, the Scan2MCNP can contribute along with other software that has been used recently in the area of medical physics, to improve the levels of quality and precision of radiotherapy treatments. In this work, medical images DICOM of the Anthropomorphic Rando Phantom were used in the process of analysis and development of computer software Scan2MCNP. However, it emphasized that the software is successful in certain situations, depending upon a number of auxiliary procedures and software that can help in the solution of certain problems in the natural radiation treatment or express agility by the team of medical physics. (author)

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

    International Nuclear Information System (INIS)

    Arikado, Takuji; Ariga, Hiroko; Kase, Manabu; Nagata, Renpei; Tashiro, Kunio

    1983-01-01

    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. (author)

  5. Static Myocardial Perfusion Imaging using denoised dynamic Rb-82 PET/CT scans

    DEFF Research Database (Denmark)

    Petersen, Maiken N.M.; Hoff, Camilla; Harms, Hans

    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....... 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...

  6. Muscle metastases: ultrasound and CT scan imaging in nine cases. Report on 9 cases

    International Nuclear Information System (INIS)

    Folinais, D.; Cluzel, Ph.; Blangy, S.; Sibert, A.; David, M.; Benacerraf, R.

    1988-01-01

    Clinical, ultrasound and CT scan examinations were carried out in 9 patients with secondary muscle lesions. All muscles can be affected but there was a marked predominance of psoas lesions (6 of the 9 cases). Two contrasting clinical pictures are seen. Secondary muscle tumors can occur during evolution of a known treated cancer (5 of the 9 cases), revealed usually by large, rarely painful, mass. CT scan imaging shows an heterogeneous mass taking up contrast and often partially necrotic, the lesions appearing hypoechogenic or heterogeneous on ultrasound exmination. Certain lesions can be totally necrotic. In some cases (4 of the 9 patients) the muscle metastases revealed the presence of a tumor. Symptomatology may be atypical and lead to a delay in diagnosis. Fine needle puncture biopsy can detect the secondary origin of the muscle lesion and also the primary tumor site (4 out of 9 cases), bronchopulmonary and colon cancer predominating. Images are however non-specific and in the absence of NMR imaging the muscle or lymph node metastases can be confused, although this has no practic consequences since treatment is identical [fr

  7. [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.

  8. Laterality of cerebral hemispheres on CT scan and gross motor function in severely handicapped children

    Energy Technology Data Exchange (ETDEWEB)

    Iwasaki, Nobuaki; Hamano, Kenzo; Nakamoto, Natsue; Okada, Yusuke [Tsukuba Univ., Ibaraki (Japan); Takeya, Toshiki

    1997-06-01

    The relation between brain damage and gross motor function in severely handicapped children (spastic type) was studied. The subjects were fifteen cases with laterality in their cerebral hemisphere CT scans (laterality group) and 28 cases with no laterality (control group). All cases were divided into four groups according to the level of gross motor function. The grade of brain damage was estimated based on CT scan analysis using the following parameters and index: maximum frontal extracerebral space (ES), maximum width of Sylvian fissure (SY), Evans` ratio, and cella media index. In the laterality group, the parameters and index were measured for both cerebral hemispheres, respectively. In the more severely disturbed hemisphere of the laterality group, ES and SY were significantly enlarged compared with those of the cases with the same level of motor function in the control group (p<0.01). In the less severely disturbed hemisphere of the laterality group, the ES, SY, Evans` ratio and cell media index were not significantly enlarged compared to cases with the same level of motor function as the control group. These findings may indicate that gross motor function of severely handicapped children is closely related to the less severely disturbed cerebral hemisphere. (author)

  9. 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.

  10. 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.

  11. Detection of treatment setup errors between two CT scans for patients with head and neck cancer

    International Nuclear Information System (INIS)

    Ezzell, Leah C.; Hansen, Eric K.; Quivey, Jeanne M.; Xia Ping

    2007-01-01

    Accuracy of treatment setup for head and neck patients undergoing intensity-modulated radiation therapy is of paramount importance. The conventional method using orthogonal portal images can only detect translational setup errors while the most frequent setup errors for head and neck patients could be rotational errors. With the rapid development of image-guided radiotherapy, three-dimensional images are readily acquired and can be used to detect both translational and rotational setup errors. The purpose of this study is to determine the significance of rotational variations between two planning CT scans acquired for each of eight head and neck patients, who experienced substantial weight loss or tumor shrinkage. To this end, using a rigid body assumption, we developed an in-house computer program that utilizes matrix transformations to align point bony landmarks with an incremental best-fit routine. The program returns the quantified translational and rotational shifts needed to align the scans of each patient. The program was tested using a phantom for a set of known translational and rotational shifts. For comparison, a commercial treatment planning system was used to register the two CT scans and estimate the translational errors for these patients. For the eight patients, we found that the average magnitudes and standard deviations of the rotational shifts about the transverse, anterior-posterior, and longitudinal axes were 1.7±2.3 deg., 0.8±0.7 deg., and 1.8±1.1 deg., respectively. The average magnitudes and standard deviations of the translational shifts were 2.5±2.6 mm, 2.9±2.8 mm, 2.7±1.7 mm while the differences detected between our program and the CT-CT fusion method were 1.8±1.3 mm, 3.3±5.4 mm, and 3.0±3.4 mm in the left-right, anterior-posterior, and superior-inferior directions, respectively. A trend of larger rotational errors resulting in larger translational differences between the two methods was observed. In conclusion, conventional

  12. Sensitivity calibration procedures in optical-CT scanning of BANG 3 polymer gel dosimeters

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Y.; Wuu, Cheng-Shie; Maryanski, Marek J. [Department of Radiation Oncology, Columbia University, New York, New York 10032 (United States); Department of Radiation Oncology, Columbia University, New York, New York 10032 and MGS Research Inc., Madison, Connecticut 06443 (United States)

    2010-02-15

    The dose response of the BANG 3 polymer gel dosimeter (MGS Research Inc., Madison, CT) was studied using the OCTOPUS laser CT scanner (MGS Research Inc., Madison, CT). Six 17 cm diameter and 12 cm high Barex cylinders, and 18 small glass vials were used to house the gel. The gel phantoms were irradiated with 6 and 10 MV photons, as well as 12 and 16 MeV electrons using a Varian Clinac 2100EX. Three calibration methods were used to obtain the dose response curves: (a) Optical density measurements on the 18 glass vials irradiated with graded doses from 0 to 4 Gy using 6 or 10 MV large field irradiations; (b) optical-CT scanning of Barex cylinders irradiated with graded doses (0.5, 1, 1.5, and 2 Gy) from four adjacent 4x4 cm{sup 2} photon fields or 6x6 cm{sup 2} electron fields; and (c) percent depth dose (PDD) comparison of optical-CT scans with ion chamber measurements for 6x6 cm{sup 2}, 12 and 16 MeV electron fields. The dose response of the BANG 3 gel was found to be linear and energy independent within the uncertainties of the experimental methods (about 3%). The slopes of the linearly fitted dose response curves (dose sensitivities) from the four field irradiations (0.0752{+-}3%, 0.0756{+-}3%, 0.0767{+-}3%, and 0.0759{+-}3% cm{sup -1} Gy{sup -1}) and the PDD matching methods (0.0768{+-}3% and 0.0761{+-}3% cm{sup -1} Gy{sup -1}) agree within 2.2%, indicating a good reproducibility of the gel dose response within phantoms of the same geometry. The dose sensitivities from the glass vial approach are different from those of the cylindrical Barex phantoms by more than 30%, owing probably to the difference in temperature inside the two types of phantoms during gel formation and irradiation, and possible oxygen contamination of the glass vial walls. The dose response curve obtained from the PDD matching approach with 16 MeV electron field was used to calibrate the gel phantom irradiated with the 12 MeV, 6x6 cm{sup 2} electron field. Three-dimensional dose distributions

  13. Case of asymmetrical arthrogryposis. A clinical study and a preliminary report on the value of CT-scanning

    Energy Technology Data Exchange (ETDEWEB)

    Hageman, G.; Vette, J.K.; Willemse, J. (University Hospital, Utrecht (Netherlands))

    1983-01-01

    Following the introduction of the conception that arthrogryposis is a symptom and not a clinical entity, a case of the very rare asymmetric form of neurogenic arthrogryposis is presented. The asymmetry of congenital contractures and weakness is associated with hemihypotrophy. The value of muscular CT-scanning prior to muscle biopsy is demonstrated. Muscular CT-scanning shows the extension of adipose tissue, which has replaced damaged muscles and therby indicates the exact site for muscle biopsy. Since orthopaedic treatment in arthrogryposis can be unrewarding due to severe muscular degeneration, preoperative scanning may provide additional important information on muscular function and thus be of benefit for surgery. The advantage of muscular CT-scanning in other forms of arthrogryposis requires further determination. The differential diagnosis with Werdnig-Hoffmann disease is discussed.

  14. Effect of gantry rotation speed and scan mode on peristalsis motion artifact frequency and severity at abdominal CT.

    Science.gov (United States)

    Shah, Rutwik; Khoram, Rhanna; Lambert, Jack W; Sun, Yuxin; Wang, Zhen J; Webb, Emily M; Yeh, Benjamin M

    2018-02-15

    The purpose of the study was to understand the effect of CT gantry speed and axial vs. helical scan mode on the frequency and severity of bowel peristalsis artifacts. We retrospectively identified 150 oncologic abdominopelvic CT scans obtained on a 256 slice CT scanner: 50 scans obtained with Axial mode and 0.5-s gantry rotation time (Slow-Axial); 50 with Axial mode and 0.28-s gantry rotation time (Fast-Axial); and 50 scans with Helical mode and 0.28-s gantry rotation time (Fast-Helical). The patients included 74 women and 76 men with a mean age of 61 years (range 22-85 years). Two readers viewed all CT scans to record the presence and severity of bowel peristalsis artifact, location of artifact (stomach, duodenum/jejunum, ileum, and colon) and artifact location relative to bowel interface (gas-bowel, fluid-bowel, and gas-fluid). The severity of artifacts was recorded subjectively on a 3-point scale, and objectively based on maximum length of the artifact. Peristalsis artifact was more commonly seen with Slow-Axial scan acquisition (37 of 50 patient scans, or 74%) than Fast-Axial (15 in 50 patient scans, or 30%, p peristalsis artifacts were not significantly different between scan techniques. Peristalsis artifacts are common at abdominopelvic CT scans. Fast gantry rotation speed significantly reduces the frequency of bowel peristalsis artifacts and should be a consideration when imaging of bowel and structures near bowel is critical.

  15. 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

  16. Determination of entry site for acute type A aortic dissection by initial enhanced CT-scan

    International Nuclear Information System (INIS)

    Mase, Takenori; Narumiya, Chihiro; Aoyama, Takahiko; Nagata, Yoshihisa

    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 that

  17. A follow-up study by CT scan of intracranial hemorrhages in newborn children

    International Nuclear Information System (INIS)

    Shibata, Iekado; Kushida, Yoshimasa; Seiki, Yoshikatsu; Tsutsumi, Shunichiro; Kuramitsu, Toru

    1983-01-01

    Intracranial hemorrhages in perinatal babies and their sequelae are two of the targets of recent investigations. This study was designed to make clear the correlation between intracranial hemorrhage in perinates and the sequential widening of the cerebrospinal fluid space, including ventricles. 600 cases with moderate or severe clinical symptoms were treated in the Neonatal Intensive Care Unit of the Toho University Hospital from February, 1981, to October, 1982. Of these, 137 cases were suspected clinically to have had an intracranial hemorrhage at birth. In the CT study of these cases, intracranial hemorrhages of various types were confirmed in 55 cases. These included subarachnoid hemorrhages (29 cases), intraventricular hemorrhages (3 cases), intracerebral hemorrhages (3 cases), and combined hemorrhages (20 cases). A follow-up check of these cases by means of CT scan and neurological examinations was done for a period of from 40 days to 20 months. In 35 cases (63.5%) out of the 55, a temporary or persistent enlagement of the ventricle and/or widenings of the CSF space of various types were demonstrated. The latter included subdural effusion, the widening of the Sylvian fissure and/or interhemispheric fissure, and the widening of the basal cisterns. An enlargement of the ventricle occurred often following an intraventricular or intracerebral hemorrhage. On the other hand, subdural effusion was a common sequela after a subarachnoid hemorrhage. These changes in the ventricle or CSF space seem to be benign in nature and were improved in most cases during the period of the follow-up study. The ventricular enlargement disappeared substantially in 5 cases, and in the remaining 30 cases the abnormalities on the CT scans were much improved. Clinically, retarded physical development was evident in 3 cases, but the others showed no developmental retardation

  18. CT scanning for the detection of tuberculous mediastinal and hilar lymphadenopathy in children

    International Nuclear Information System (INIS)

    Andronikou, S.; Joseph, E.; Lucas, S.; Brachmeyer, S.; Toit, G. du; Zar, H.; Swingler, G.

    2004-01-01

    Background: The diagnosis of primary pulmonary tuberculosis (PTB) in children relies heavily on the radiographic demonstration of mediastinal lymphadenopathy. Plain radiographs may be unreliable and CT is the current 'gold standard' for demonstrating this. Only two previous studies have described the CT findings of mediastinal adenopathy exclusively in children. Objective: To determine the prevalence, distribution, characteristics and effect on the bronchial tree of mediastinal lymphadenopathy using modern CT techniques, in children suspected of PTB. Materials and methods: One hundred children (54 boys, 46 girls) with clinically suspected PTB were prospectively recruited from an overnight admission ward if they met the WHO criteria for suspected PTB. CT scans were evaluated by a panel of radiologists with regard to a predetermined set of criteria. Results: Lymph nodes were present in 92 patients, and nodes greater than 1 cm were present in 46 patients. Enhancement of lymph nodes was present in 67 patients and was almost invariably 'ghost-like' ring enhancement. Calcification was present in only 9 patients. The most common location for lymphadenopathy was the subcarinal position (n = 90), followed by the hila (n = 85; left 74, right 72, bilateral 61), the anterior mediastinum (n = 79), the precarinal position (n = 64) and the right paratracheal position (n = 63). Multiple sites of involvement were present in 88 patients, and a single site for lymphadenopathy (subcarinal) was present in only 4 patients. Bronchial compression was identified in 29 patients. Most commonly, the left main bronchus was involved (n = 21), followed by the right main bronchus (n = 14) and the bronchus intermedius (n = 8), 16 right-sided compressions in total. (orig.)

  19. 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.

  20. 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 (p<0.65, chi(2)=0.39, Fisher's exact test). Interobserver bias rates for both teams were very low (kappa=0.83). The present study shows that volume-rendered CCT images are suitable for the collection of data concerning morphologic sex determination of skulls. Thus, this method may be helpful in both actual forensic casework and the systematic reevaluation and improvement of classical anthropological methods and their adaptation to changing populations. 2010 Elsevier Ireland Ltd. All rights reserved.

  1. Ga-67 tumor scan in malignant diffuse mesothelioma. Comparison with CT and pathological findings

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Shoji; Fukumoto, Mitsutaka [Kochi Medical School, Nankoku (Japan); Motohara, Tomofumi; Oobayashi, Kayoko; Takada, Yoshiki; Tsubota, Noriaki; Sashikata, Terumasa

    1999-02-01

    Malignant diffuse mesothelioma is characterized by more difficult diagnosis and worse prognosis than other pleural tumors. In the Department of Thoracic Surgery, Hyogo Medical Center for Adults, 11 patients underwent panpleuropneumonectomy for this disease between January, 1988 and March, 1993. In 7 of these cases, Ga-67 scans were obtained before the operation. To clarify the factors affecting Ga-67 uptake in the pleural tumor, we compared Ga-67 uptake on the involved side of the thorax with CT and the pathological findings of the tumor. Regarding the use of Ga-67 scan imaging for the diagnosis of this disease, a number of related findings must be considered, such as an encircled wide Ga-67 uptake in the thickened pleural involvement and a diffuse slight Ga-67 uptake on the affected side with very slight involvement of the pleura. When the involved pleural thickness was over 6 mm, a definite correlation was found between the degree of Ga-67 uptake and the macroscopic thickness of mesothelioma in resected specimens. Thickness of the pleura on CT images demonstrates the real tumor thickness in the case of thickened involvement but in the case of thin involvement the real thickness of active mesothelioma could not be identified. No definite correlation was found between the degree of Ga-67 uptake and the histological type, or among microscopic findings, such as the extent of tumor parenchyma, interstitial volume and tumor vascularity. Our results suggest that the Ga-67 scan is very useful for revealing the extent of pleural involvement, especially when this involvement is more than 6 mm thick. (author)

  2. Screening helical CT for mass screening of lung cancer. Application of low-dose and single-breath-hold scanning

    International Nuclear Information System (INIS)

    Itoh, Shigeki; Ikeda, Mitsuru; Isomura, Takayuki; Endo, Tokiko; Yamakawa, Kouji; Itoh, Kengo; Naganawa, Shinji; Maruyama, Kunihiro; Ishigaki, Takeo

    1998-01-01

    The usefulness of helical CT with low-dose and single-breath-hold scanning was investigated for lung cancer screening. Twenty-four helical CT scans of the lung were performed using various parameters in 10 healthy volunteers. The effects of tube current and pitch were evaluated by assessment of image quality and detection of simulated nodules. Screening helical CT was performed at 120 kVp, 50 mA, 1 sec/rotation, 10 mm collimation, and a pitch of 2.0 in 110 patients. The ability of this method to detect nodules and masses, focal parenchymal opacities, and diffuse fibrotic changes was evaluated using conventional CT as the gold standard. A reduction in tube current to 50 mA did not significantly change the assessment of image quality or detection of simulated nodules. Although these factors were degraded by increasing the pitch, there was no significant difference between 1.5 and 2.0. Screening helical CT permitted the entire lung to be scanned with ease during a single-breath-hold in all patients. This method detected 177 of 196 nodules and masses (87 for 91 lesions greater than 5 mm in diameter), 54 of 57 focal parenchymal opacitied, and 15 of 15 cases with fibrotic changes. Screening helical CT with low-dose and single-breath-hold scanning shows promise for lung cancer screening. (author)

  3. Budd-Chiari syndrome: diagnosis with ultrasound and nuclear medicine calcium colloid liver scan following non-diagnostic contrasted CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Mulholland, J.P.; Fong, S.M.; Kafaghi, F.A.; Fong, W. [Royal Brisbane Hospital, Herston, QLD (Australia)

    1997-02-01

    Budd-Chiari syndrome is a rare condition characterized by thrombosis within the hepatic veins and inferior vena cava. A case of Budd-Chiari syndrome is presented in a patient who experienced acutely 3 days following laparoscopic cholecystectomy for a calculous cholecystitis. A discussion of pathology and findings on calcium colloid scintigram, CT scan and Doppler ultrasound is provided. 5 refs., 4 figs.

  4. An evaluation of CT-scan to locate the femoral head centre and its implication for hip surgeons.

    Science.gov (United States)

    Viste, Anthony; Trouillet, Franck; Testa, Rodolphe; Chèze, Laurence; Desmarchelier, Romain; Fessy, Michel-Henri

    2014-04-01

    The aim of this preliminary study was to determine the accuracy of CT-scan to locate the femoral head centre. Eleven dried femurs were included for study. Three techniques were compared to determine femoral head centre (FHC) location: CT-scan, Motion Analysis and Faro-Arm. Markers were stuck on each femur to create a system of coordinates. Femurs lied on their posterior parts (bicondylar plane). Several points around the femoral head were palpated (Motion Analysis and Faro-Arm) or determined (Amira software for CT-scans). By a least-square regression method, the FHC location in 3D was defined for each technique. The results of the FHC location determined by the CT-scan technique were compared with those measured by the faro-arm and the Motion Analysis techniques. The coordinates (X, Y, Z) of the FHC were compared between the three methods, and no statistical difference was found (p = 0.99). In a 3D plot, this gave a mean difference of 1.3 mm. The mean radius of the femoral head was of 22.5 mm (p = 0.6). CT-scan is as accurate and reliable as gold-standard techniques (motion and faro-arm). Locating FHC before and after hip arthroplasty would allow hip surgeons to determine and compare 3D orientation of the upper-end of femur: offset, height and anteversion.

  5. Comparison of CT scan and colour flow doppler ultrasound in detecting venous tumour thrombous in renal cell carcinoma

    International Nuclear Information System (INIS)

    Khan, A.R.; Anwar, K.

    2008-01-01

    Renal cell carcinoma has marked tendency to spread into renal vein, inferior vena cava and right side of heart. Extension of tumour thrombus into these veins will alter the surgical approach. We have compared the CT scan with Colour flow Doppler ultrasound in detecting venous tumour thrombus in renal vein and inferior vena cava. This cross-sectional study included 30 adult patients presenting with renal tumour. Patients of either gender were included in the study. Non probability convenience sampling was used. All patients underwent colour flow Doppler ultrasound and CT scan with contrast to asses the renal vein and inferior vena cava. The results were confirmed by intra operative findings and histopathology. The data was analyzed using SPSS version 12. Out of 30 patients, 20 (66%) were males and 10 (34%) female. The tumour was predominantly on the right side (60%), as was renal venous tumour thrombus (44%). Inferior vena cava was involved in 4 cases predominantly due to right sided tumours. The sensitivity of Doppler ultrasound in detecting renal venous tumour thrombus (88% on right and 100% on left side) was higher than CT scan (63% on right and 60% on left side). Doppler ultrasound was also superior to CT scan in detecting vena caval thrombus. The overall sensitivity of Doppler sonography was higher than CT scan in detecting tumour extension into renal veins and inferior vena cava. Therefore, it can be used as a complementary tool in equivocal cases. (author)

  6. Image-Guided Radiation Therapy for Muscle-Invasive Carcinoma of the Urinary Bladder with Cone Beam CT Scan: Use of Individualized Internal Target Volumes for a Single Patient

    Directory of Open Access Journals (Sweden)

    Gagan Saini

    2012-09-01

    Full Text Available Introduction: While planning radiation therapy (RT for a carcinoma of the urinary bladder (CaUB, the intra-fractional variation of the urinary bladder (UB volume due to filling-up needs to be accounted for. This internal target volume (ITV is obtained by adding internal margins (IM to the contoured bladder. This study was planned to propose a method of acquiring individualized ITVs for each patient and to verify their reproducibility. Methods: One patient with CaUB underwent simulation with the proposed ‘bladder protocol’. After immobilization, a planning CT scan on empty bladder was done. He was then given 300 ml of water to drink and the time (T was noted. Planning CT scans were performed after 20 min (T+20, 30 min (T+30 and 40 min (T+40. The CT scan at T+20 was co-registered with the T+30 and T+40 scans. The bladder volumes at 20, 30 and 40 min were then contoured as CTV20, CTV30 and CTV40 to obtain an individualized ITV for our patient. For daily treatment, he was instructed to drink water as above, and the time was noted; treatment was started after 20 min. Daily pre- and post-treatment cone beam CT (CBCT scans were done. The bladder visualized on the pre-treatment CBCT scan was compared with CTV20 and on the post-treatment CBCT scan with CTV30. Results: In total, there were 65 CBCT scans (36 pre- and 29 post-treatment. Individualized ITVs were found to be reproducible in 93.85% of all instances and fell outside in 4 instances. Conclusions: The proposed bladder protocol can yield a reproducible estimation of the ITV during treatment; this can obviate the need for taking standard IMs.

  7. Cavum septi pellucidi and cavum vergae. Incidence on CT scan and clinical significance

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, S.; Hojo, H.; Kataoka, K.; Yamasaki, S. (Shizuoka Children' s Hospital, Shizuoka (Japan))

    1980-10-01

    1050 CT scans of patients under 15 years were reviewed. We also investigated the clinical features of these cases and made an attempt to disclose the incidence of cavum septi pellucidi (CSP) and cavum Vergae (CV) on the CT scan and to clarify their clinical significance. As a whole, CSP was demonstrated in 23 patients (2.2%), CV in 4 (0.4%), and both CSP and CV at the same time in 31 (3.0%). The incidence of CSP and CV in each age bracket decreased with an advance in age. No sexual differences were found. The incidences of CSP and CV in the patients with convulsive disorders, developmental delay, and other disorders were 6.4%, 5.1%, and 5.2% respectively. Of 64 patients with febrile convulsion, 4 had both CSP and CV at the same time, while one had only CSP. The four patients with both CSP and CV had convulsions three or more times, while the patient with only CSP had only one. These results suggested that those patients with febrile convulsions who had both CSP and CV at the same time were liable to have recurrent convulsions. Of 32 patients with benign infantile convulsions, only one had both CSP and CV. On the other hand, of 29 patients with infantile spasms, 2 had only CSP, and another 2 had both CSP and CV. Some patients with infantile spasms had CT scans demonstrating cerebral atrophy, porencephaly, cerebral angioma, and calcification in the brain, suggesting various types of etiology. Of 187 patients with other convulsive disorders, 4 had only CSP and 6 had both CSP and CV. Of 468 patients with developmental delay, 13 had only CSP (2.8%), one had only CV (0.2%), and 10 had both (2.1%). Of these 24 patients with developmental delay who had CSP and/or CV, 14 had cerebral atrophy besides, suggesting other etiological factors. Of 270 patients with other disorders, 3 had only CSP (1.1%), other 3 had only CV (1.1%), and 8 had both (3.0%).

  8. Development of a database of organ doses for paediatric and young adult CT scans in the United Kingdom

    Science.gov (United States)

    Kim, K. P.; Berrington de González, A.; Pearce, M. S.; Salotti, J. A.; Parker, L.; McHugh, K.; Craft, A. W.; Lee, C.

    2012-01-01

    Despite great potential benefits, there are concerns about the possible harm from medical imaging including the risk of radiation-related cancer. There are particular concerns about computed tomography (CT) scans in children because both radiation dose and sensitivity to radiation for children are typically higher than for adults undergoing equivalent procedures. As direct empirical data on the cancer risks from CT scans are lacking, the authors are conducting a retrospective cohort study of over 240 000 children in the UK who underwent CT scans. The main objective of the study is to quantify the magnitude of the cancer risk in relation to the radiation dose from CT scans. In this paper, the methods used to estimate typical organ-specific doses delivered by CT scans to children are described. An organ dose database from Monte Carlo radiation transport-based computer simulations using a series of computational human phantoms from newborn to adults for both male and female was established. Organ doses vary with patient size and sex, examination types and CT technical settings. Therefore, information on patient age, sex and examination type from electronic radiology information systems and technical settings obtained from two national surveys in the UK were used to estimate radiation dose. Absorbed doses to the brain, thyroid, breast and red bone marrow were calculated for reference male and female individuals with the ages of newborns, 1, 5, 10, 15 and 20 y for a total of 17 different scan types in the pre- and post-2001 time periods. In general, estimated organ doses were slightly higher for females than males which might be attributed to the smaller body size of the females. The younger children received higher doses in pre-2001 period when adult CT settings were typically used for children. Paediatric-specific adjustments were assumed to be used more frequently after 2001, since then radiation doses to children have often been smaller than those to adults. The

  9. Leukemia and brain tumors among children after radiation exposure from CT scans: design and methodological opportunities of the Dutch Pediatric CT Study

    NARCIS (Netherlands)

    Meulepas, Johanna M.; Ronckers, Cécile M.; Smets, Anne M. J. B.; Nievelstein, Rutger A. J.; Jahnen, Andreas; Lee, Choonsik; Kieft, Mariëtte; Laméris, Johan S.; van Herk, Marcel; Greuter, Marcel J. W.; Jeukens, Cécile R. L. P. N.; van Straten, Marcel; Visser, Otto; van Leeuwen, Flora E.; Hauptmann, Michael

    2014-01-01

    Computed tomography (CT) scans are indispensable in modern medicine; however, the spectacular rise in global use coupled with relatively high doses of ionizing radiation per examination have raised radiation protection concerns. Children are of particular concern because they are more sensitive to

  10. Leukemia and brain tumors among children after radiation exposure from CT scans : design and methodological opportunities of the Dutch Pediatric CT Study

    NARCIS (Netherlands)

    Meulepas, Johanna M.; Ronckers, Cecile M.; Smets, Anne M. J. B.; Nievelstein, Rutger A. J.; Jahnen, Andreas; Lee, Choonsik; Kieft, Mariette; Lameris, Johan S.; van Herk, Marcel; Greuter, Marcel J. W.; Jeukens, Cecile R. L. P. N.; van Straten, Marcel; Visser, Otto; van Leeuwen, Flora E.; Hauptmann, Michael

    Computed tomography (CT) scans are indispensable in modern medicine; however, the spectacular rise in global use coupled with relatively high doses of ionizing radiation per examination have raised radiation protection concerns. Children are of particular concern because they are more sensitive to

  11. Head and neck tumors and neck node metastasis: comparison of Ga-67 scan and CT findings

    International Nuclear Information System (INIS)

    Kwon, Sam Ok; Kim, Jong Min; Bae, Sang Kyun; Kim, Sang Suk; Oh, Kyeung Seung; Joh, Young Duk

    1995-01-01

    To assess relative diagnostic value of Ga-67 planar, Ga-67 SPECT, and CT images for detection of head and neck tumors and cervical lymph node metastasis. Thirty eight patients of pathologically proven head and neck tumors including squamous cell carcinomas(n=32), malignant lymphomas(n=3), undifferentiated carcinomas(n=2), adenocarcinomas(n=1) were enrolled in this study. Ga-67 planar and SPECT images were obtained with intravenous injection of 5mCi of Ga-67 citrate. On the basis of 30 and 20 mm in the greatest diameter of cervical lymph nodes, we compared lesion detectability of Ga-67 planar, SPECT, and CT. Thirty eight cases of head and neck tumors were detected in 29 cases (76.3%) with Ga-67 planar image, 37 cases (97.3%) with Ga-67 SPECT, and 32 cases (84.2%) with CT. 25 of 32 squamous cell carcinomas were positive with Ga-67 planar image and all of 32 cases with Ga-67 SPECT. Both of two undifferentiated carcinomas were positive with Ga-67 planar and SPECT images. Two of three malignant lymphomas were positive with Ga-67 planar image and all of three with Ga-67 SPECT. Eight of nine tumors were negative with Ga-67 planar image and those were less than 30 mm. One case of adenocarcinoma was negative with Ga-67 planar and SPECT images. Seven of nine lymph nodes greater than 30 mm were positive with Ga-67 planar image and all of nine with Ga-67 SPECT. On the basis of 20 mm in greatest diameter, 16 of 21 lymph nodes greater than 20 mm were positive with Ga-67 planar and SPECT images. CT providing better resolution than Ga-67 scan permitted analysis of size and location of metastatic cervical nodes, however primary tumors of oral cavity, vocal cord, and nasopharynx were often not detected on CT when metallic and motion artifacts were present, where Ga-67 SPECT was useful. Ga-67 SPECT enabled better anatomical localization than Ga-67 planar image and was useful in detection of lymph nodes greater than 30 mm

  12. Survey of 37 cases with basal ganglia calcification. Relationship to CT-scan findings, underlying diseases, and epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Ogata, Akira; Ishida, Shiro; Wada, Toyoji (National Epilepsy Center, Shizuoka Higashi Hospital (Japan))

    1984-11-01

    Of 5,987 patients (5,196 epileptic patients and 791 non-epileptic patients) undergoing CT-scan, calcification of the bilateral basal ganglia was detected in 28 epileptic patients and 9 non-epileptic patients. Relationship among CT-scan findings, underlying diseases and epilepsy was studied. CT-scan findings could be classified into the localized type in which calcification was limited to the globus pallidus in 33 patients and diffuse type in which it extended to the putamen in 4 patients. Localized type increased with age. It was about 70 times higher in patients above the age of 50 than in patients below the age of 10. The female to male ratio was 2:1. Underlying diseases were idiopathic or familial in cases of localized type, and hypoparathyroidism in cases of diffuse type. Seventy-five percent of the epileptic patients had partial epilepsy. There seems not to be direct correlation between basal ganglia calcification and epilepsy.

  13. X-ray CT Scanning Reveals Long-Term Copper Pollution Effects on Functional Soil Structure

    DEFF Research Database (Denmark)

    Naveed, Muhammad; Møldrup, Per; Homstrup, Martin

    Soil structure plays the main role in the ability of the soil to fulfill essential soil functions such as the root growth, rate of water infiltration and retention, transport of gaseous and chemicals/pollutants through the soil. Soil structure is a dynamic soil property and affected by various...... 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...... columns, macroporosity showed a significant decrease along the column depth. The results suggest that Cu contamination has a strong impact on soil structure and hence on all soil physical and biological processes....

  14. The use of CT scanning for the study of posterior lumbar intervertebral articulations

    International Nuclear Information System (INIS)

    Hermanus, N.; Becker, D. de; 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. (orig.)

  15. 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.

  16. 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.

  17. CT scan lesion localization and response to melodic intonation therapy with nonfluent aphasia cases.

    Science.gov (United States)

    Naeser, M A; Helm-Estabrooks, N

    1985-06-01

    The purpose of this retrospective study was to investigate the relationship between CT scan lesion localization and good or poor response to Melodic Intonation Therapy (MIT) as measured by pre- and post-MIT treatment scores. The four good response (GR) cases improved in speech characteristics ratings for Phrase Length and Grammatical Form on the Boston Diagnostic Aphasia Examination; the four poor response (PR) cases showed no improvement. The GR cases had lesions which involved Broca's area and/or white matter deep to it plus large superior lesion extension into periventricular white matter deep to the lower motor cortex area for face. These GR cases had no large lesion in Wernicke's area and no lesion in the temporal isthmus or the right hemisphere. The PR cases, however, had bi-lateral lesions or lesion including Wernicke's area or the temporal isthmus.

  18. 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.

  19. 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,

  20. 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.

  1. Comparison of two different segmentation methods on planar lung perfusion scan with reference to quantitative value on SPECT/CT

    International Nuclear Information System (INIS)

    Suh, Min Seok; Kang, Yeon Koo; Ha, Seung Gyun

    2017-01-01

    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

  2. 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.

  3. Utility of FDG-PET-CT scanning in assessing the extent of disease activity and response to treatment in sarcoidosis

    Directory of Open Access Journals (Sweden)

    Randeep Guleria

    2014-01-01

    Full Text Available Background: Radionuclide imaging modalities have increasingly been evaluated in the assessment of organ involvement in sarcoidosis. Fluoro-deoxyglucose positron emission tomography-computed tomography (FDG-PET-CT scanning has received increasing attention in the recent years. The aim of our study was to evaluate the utility of FDG-PET-CT in determining the extent of organ involvement and disease activity in patients of sarcoidosis and to assess its utility in the evaluation of response to therapy. The secondary objective was to compare the agreement between clinical, radiological (HRCT and metabolic indices (FDG-PET-CT of disease activity. Materials and Methods: This was a prospective observational study conducted between March 2007 and December 2008 at a tertiary care referral center in north India. Twenty-five symptomatic and histopathologically proven cases of sarcoidosis underwent FDG-PET-CT scanning at baseline and a follow-up scan in 21 patients at 6-9 months post-treatment with glucocorticoids. Results: FDG-PET-CT scan detected metabolic disease activity in 24 of the 25 patients with clinically active sarcoidosis. It also demonstrated many clinically inapparent sites of disease activity. Complete or partial metabolic response was seen in 17 of the 21 patients in whom a follow-up scan was available. Substantial degree of agreement was found between the metabolic response and the radiological response, whereas moderate agreement was found between clinical and metabolic responses. Conclusions: FDG-PET-CT scanning is a useful imaging modality to assess disease activity, extent of disease involvement and response to treatment in clinically active sarcoidosis. There is substantial agreement between the HRCT and metabolic parameters of disease activity. Further, large sample size studies are proposed in order to identify the subset of patients who are likely to benefit the most from this sensitive modality of imaging, especially in developing

  4. Methodologies for Development of Patient Specific Bone Models from Human Body CT Scans

    Science.gov (United States)

    Chougule, Vikas Narayan; Mulay, Arati Vinayak; Ahuja, Bharatkumar Bhagatraj

    2016-06-01

    This work deals with development of algorithm for physical replication of patient specific human bone and construction of corresponding implants/inserts RP models by using Reverse Engineering approach from non-invasive medical images for surgical purpose. In medical field, the volumetric data i.e. voxel and triangular facet based models are primarily used for bio-modelling and visualization, which requires huge memory space. On the other side, recent advances in Computer Aided Design (CAD) technology provides additional facilities/functions for design, prototyping and manufacturing of any object having freeform surfaces based on boundary representation techniques. This work presents a process to physical replication of 3D rapid prototyping (RP) physical models of human bone from various CAD modeling techniques developed by using 3D point cloud data which is obtained from non-invasive CT/MRI scans in DICOM 3.0 format. This point cloud data is used for construction of 3D CAD model by fitting B-spline curves through these points and then fitting surface between these curve networks by using swept blend techniques. This process also can be achieved by generating the triangular mesh directly from 3D point cloud data without developing any surface model using any commercial CAD software. The generated STL file from 3D point cloud data is used as a basic input for RP process. The Delaunay tetrahedralization approach is used to process the 3D point cloud data to obtain STL file. CT scan data of Metacarpus (human bone) is used as the case study for the generation of the 3D RP model. A 3D physical model of the human bone is generated on rapid prototyping machine and its virtual reality model is presented for visualization. The generated CAD model by different techniques is compared for the accuracy and reliability. The results of this research work are assessed for clinical reliability in replication of human bone in medical field.

  5. Urinary catecholamines in patients with acute stroke, in reference to CT scan findings

    International Nuclear Information System (INIS)

    Yoshino, Kimiaki

    1985-01-01

    The amount of norepinephrine (NE) and epinephrine (E) in the urine of 160 stroke patients were measured both at the acute stage and at the chronic stage (31 days or later) of the diseases and a CT scan was taken simultaneously. The urinary NE and E were separated by the high performance liquid chromatography and measured by trihydroxyindole method. Forty five healthy subjects were employed as a control group. The results were as follows: 1) In subarachnoid hemorrhage and intracerebral hemorrhage the NE and E and in cerebral infarction the NE were significantly increased in the acute stage. But, when divided by CT scan findings, the group of intracerebral hemorrhage without perforation into the ventricles showed increases of NE only and those without deviation of midline showed no significant increase of the NE and E. In cases of large cerebral infarction, both NE and E were significantly increased. It is supposed that not only the type of the disease but also the facfors such as its size, perforation into the ventricles and deviation of the midline may change activities of secretion of NE and E. 2) The NE/E ratio was significantly low in the group of intracerebral hemorrhage with perforation into the ventricles (p < 0.001) and the ratio was significantly lower in the thalamic hemorrhage than in the putaminal hemorrhage (p < 0.02). The rate of perforation into the ventricles was significantly higher in the thalamic hemorrhage (78.6 %) than that of the putaminal hemorrhage (10.5 %). 3) In the chronic stage of the stroke, the NE and E (especially E) were decreased and showed a high NE/E. ratio. (author)

  6. Efficient organ localization using multi-label convolutional neural networks in thorax-abdomen CT scans

    Science.gov (United States)

    Efrain Humpire-Mamani, Gabriel; Arindra Adiyoso Setio, Arnaud; van Ginneken, Bram; Jacobs, Colin

    2018-04-01

    Automatic localization of organs and other structures in medical images is an important preprocessing step that can improve and speed up other algorithms such as organ segmentation, lesion detection, and registration. This work presents an efficient method for simultaneous localization of multiple structures in 3D thorax-abdomen CT scans. Our approach predicts the location of multiple structures using a single multi-label convolutional neural network for each orthogonal view. Each network takes extra slices around the current slice as input to provide extra context. A sigmoid layer is used to perform multi-label classification. The output of the three networks is subsequently combined to compute a 3D bounding box for each structure. We used our approach to locate 11 structures of interest. The neural network was trained and evaluated on a large set of 1884 thorax-abdomen CT scans from patients undergoing oncological workup. Reference bounding boxes were annotated by human observers. The performance of our method was evaluated by computing the wall distance to the reference bounding boxes. The bounding boxes annotated by the first human observer were used as the reference standard for the test set. Using the best configuration, we obtained an average wall distance of 3.20~+/-~7.33 mm in the test set. The second human observer achieved 1.23~+/-~3.39 mm. For all structures, the results were better than those reported in previously published studies. In conclusion, we proposed an efficient method for the accurate localization of multiple organs. Our method uses multiple slices as input to provide more context around the slice under analysis, and we have shown that this improves performance. This method can easily be adapted to handle more organs.

  7. 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.

  8. An Evaluation of pectus excavatum by means of body surface measurements on chest CT scans

    International Nuclear Information System (INIS)

    Hirotani, Taichi; Ohama, Kazunori; Shimotake, Takashi; Ishikawa, Nobuki; Watanabe, Reiji

    2009-01-01

    The aim of this study is to determine whether the body surface index replaces the Haller index in order to evaluate the severity of pectus excavatum. Sixty-nine cases with a diagnosis of pectus excavatum between August 2001 and January 2008 were prospectively enrolled in the study. The anterior-posterior chest dimension, lateral chest dimension and depth of the most profound depressed area were measured. The body surface index was expressed as an equation A/(B-C), where A was the transverse diameter, B was the anterior-posterior diameter and C was the depth of the depressed area. This index was compared to the Haller index in each patient. In this study, each value was measured on a chest CT scan. The body surface index significantly correlated with the Haller index, in which the coefficient of correlation was 0.879 (p<0.01). The body surface index corresponding to Haller index 3.25 seems to be 1.67. We could find the body surface index corresponding to each Haller index. We propose that an evaluation of pectus excavatum by means of body surface measurements is clinically useful, and may replace the Haller index. The body surface index may allow us to assess the severity of pectus excavatum without a CT scan, resulting in a reduction of radiation exposure for children with pectus excavatum. It's possible to evaluate the body surface index by using a relational table between this index and the Hailer index. We'll evaluate the body surface index by using values measured on a real body. (author)

  9. 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

  10. WAZA-ARI. A dose assessment system for patients in CT scan

    International Nuclear Information System (INIS)

    Sato, Kaoru; Takahashi, Fumiaki; Endo, Akira; Ono, Koji; Ban, Nobuhiko; Hasegawa, Takayuki; Katsunuma, Yasushi; Yoshitake, Takayasu; Kai, Michiaki

    2015-01-01

    The Japan Atomic Energy Agency (JAEA) are now developing WAZA-ARI for improvement of management of exposure doses due to CT examination under the joint research with the Oita University of Nursing and Health Sciences. The trial version of WAZA-ARI has been released on 21 December 2012. In trial version, users can perform dose assessment by using organ dose database based on the average adult Japanese male (JM-103) and female (JF-103) voxel phantoms and a 4 years old female voxel phantom (UFF4). The homepage of WAZA-ARI has been accessed over 1000 times per month and 28421 times by the end of September 2014. We are developing WAZA-ARI version 2 as the extension version of dose calculation functions of WAZA-ARI. WAZA-ARI version 2 will be released by the end of March 2015. In WAZA-ARI version 2. Users can upload dose calculation results to WAZA-ARI version 2 server, and utilize improvement of the dose management of patients and the optimization of CT scan conditions. (author)

  11. Use of lead shielding on pregnant patients undergoing CT scans: Results of an international survey

    Energy Technology Data Exchange (ETDEWEB)

    Iball, Gareth R., E-mail: gri@medphysics.leeds.ac.u [Department of Medical Physics and Engineering, Old Medical School, Leeds General Infirmary, Leeds, W. Yorkshire LS1 3EX (United Kingdom); Brettle, David S. [Department of Medical Physics and Engineering, Old Medical School, Leeds General Infirmary, Leeds, W. Yorkshire LS1 3EX (United Kingdom)

    2011-05-15

    Aim: An online survey has been used to assess the use of abdominal lead shielding on pregnant patients undergoing CT scans. The aim of the study was to identify potential geographical variations in the use of such shielding as well as the opinions of the users in terms of the weight, manoeuvrability and ergonomics of the lead shields. Materials and methods: The online questionnaire was distributed to CT Radiographers in the UK, Europe, North America and Australia and responses were gathered electronically over a six month period. All completed responses were downloaded and subsequently analysed for each geographical region. Results: In total, 390 completed questionnaires were received with over 100 from each of the UK, North America and Australia. The use of lead shielding was found to vary significantly across the globe with the highest usage in North America (94.5%) and the lowest usage in Europe (46.3%). Approximately 20% of all respondents said that they experienced occupationally related back pain and 25% of all respondents said that patients complained about the weight of the shielding. Conclusion: Significant geographical variations in both the use of lead shielding for foetal radiation protection and the users' opinions of the shielding devices that are used have been identified and it has become clear that existing shielding solutions are not optimised for this task.

  12. CT-Scans of Cochlear Implant Patients with Characteristics of Pendred Syndrome

    Directory of Open Access Journals (Sweden)

    Sebastian Roesch

    2013-12-01

    Full Text Available Background: Sensorineural hearing loss (SNHL in newborns is estimated with an incidence around 1:10,000 per year and is divided into syndromic and non-syndromic forms. In case of present retrocochlear function‚ cochlear implantation allows speech and cognitive development in affected children, comparable to that of normal hearing children. Pathogenesis of SNHL remains unclear in many cases. Imaging of the temporal bone, such as computed tomography (CT and magnetic resonance imaging (MRI, can reveal conspicuous findings, e.g. enlarged vestibular aqueduct (EVA and Mondini malformation (MM of the cochlea. These malformations can be a clinical sign for Pendred syndrome. Methods: We screened CT scans of 75 cochlear implant patients for EVA and MM. Results: Six patients were observed to have either EVA alone (n=3, or MM alone (n=2, or a combination of both (n=1. Further malformations of the temporal bone could be found within the whole group, as well. Conclusion: Our results confirm the general opinion on EVA and MM, being commonly found in patients with SNHL. A possible association with Pendred syndrome needs to be confirmed by genetic investigations with search for mutations in the SLC26A4 gene and further clinical tests, such as Perchlorate test for surveillance of thyroid function.

  13. Investigation of the vestibular aqueduct and the cochlear aqueduct by temboral bone CT scan

    International Nuclear Information System (INIS)

    Shimizu, Ryuichi; Kamei, Tamio; Ito, Fumihide

    1984-01-01

    The visualization of the vestibular aqueduct and the cochlear aqueduct was investigated by temporal bone CT scan. The vestibular aqueduct was visualized in horizontal CT sections of 70.0% of normal ears, 61.5% of ears with chronic otitis media, 58.3% of ears with combined hearing impairment, 66.7% of ears in cases of sudden deafness, 70.8% of ears of patients with sensorineural hearing impairment without sudden deafness, 71.4% of cases of vertigo without hearing impairment and 12.5% of both diseased and contralateral ears of patients with Meniere's disease. Only in Meniere's disease was the vestibular aqueduct less visible in the diseased than in the normal ear (P<0.01). The cochlear aqueduct was visible in coronal sections of 50.0% of normal ears, 76.9% of those with chronic otitis media, 58.3% of those with combined hearing impairment, 66.7% of those with sudden deafness 41.7% of those with sensorineural hearing impairment without sudden deafness, 50.0% of the diseased ears of patients with Meniere's disease, 37.5% of the contralateral ears of those with Meniere's disease and 64.3% of those with vertigo without hearing impairment. Although the cochlear aqueduct was thus highly demonstrable in patients with chronic otitis media or sudden deafness, the difference between the percentage of visualization in these diseased and in normal ears was not statistically significant. (author)

  14. Clinical, pathological and molecular evaluations and CT scan screening of coenurosis (Coenurus cerebralis in sheep and calves

    Directory of Open Access Journals (Sweden)

    Abdullah Gazioglu

    Full Text Available Abstract The aims of this study were to diagnose coenurosis by means of computerized tomography (CT scan imaging and molecular characterization of the CO1 gene using the polymerase chain reaction (PCR. Sheep and calves were necropsied, and CT scans on the cephalic region were performed on the animals. Sections of brain tissue infected with parasites were then stained with hematoxylin and eosin for microscopic examination. Material collected from brain cysts was fixed in 70% ethanol. PCR amplification was carried out using the CO1 mitochondrial gene. A total of 60 calves and 80 sheep were examined clinically and, of these, 15 calves and 38 sheep showed signs of depression, with counterclockwise circling movements and altered head carriage. Four sheep and one calf were necropsied, and C. cerebralis cysts were detected in all of them. A hypodense cyst was monitored in the right cerebellar hemisphere on a CT scan on one sheep. A cyst was found in the left frontal lobe on a CT scan on one calf. Microscopically, C. cerebralis cysts were surrounded by a fibrous or epithelial wall that presented necrosis on cerebral sections of both the sheep and the cattle. The CO1-PCR assay yielded a 446 bp band, which was sequenced and phylogenetically analyzed: the results confirmed the presence of T. multiceps. This study reports the first use of CT imaging on naturally infected calves and sheep for diagnosing coenurosis.

  15. Alveolar architecture of clear cell renal carcinomas (≤5.0 cm) show high attenuation on dynamic CT scanning

    International Nuclear Information System (INIS)

    Fujimoto, Hiroyuki; Wakao, Fumihiko; Moriyama, Noriyuki; Tobisu, Kenichi; Kakizoe, Tadao; Sakamoto, Michiie

    1999-01-01

    To establish the correlation between tumor appearance on CT and tumor histology in renal cell carcinomas. The density and attenuation patterns of 96 renal cell carcinomas, each ≤5 cm in greatest diameter, were studied by non-enhanced CT and early and late after bolus injection of contrast medium using dynamic CT. The density and attenuation patterns and pathological maps of each tumor were individually correlated. High attenuated areas were present in 72 of the 96 tumors on early enhanced dynamic CT scanning. All 72 high attenuated areas were of the clear cell renal cell carcinoma and had alveolar architecture. The remaining 24 tumors that did not demonstrate high attenuated foci on early enhanced scanning included three clear cell, nine granular cell, six papillary, five chromophobe and one collecting duct type. With respect to tumor architecture, all clear cell tumors of alveolar architecture demonstrated high attenuation on early enhanced scanning. Clear cell renal cell carcinomas of alveolar architecture show high attenuation on early enhanced dynamic CT scanning. A larger number of patients are indispensable to obtaining clear results. However, these findings seem to be an important clue to the diagnosis of renal cell carcinomas as having an alveolar structure. (author)

  16. 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...

  17. Effect of CT scanning parameters on volumetric measurements of pulmonary nodules by 3D active contour segmentation: a phantom study

    International Nuclear Information System (INIS)

    Way, Ted W; Chan, H-P; Goodsitt, Mitchell M; Sahiner, Berkman; Hadjiiski, Lubomir M; Zhou Chuan; Chughtai, Aamer

    2008-01-01

    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

  18. 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.

  19. Morphometric studies on the facial skeleton of humans and pongids based on CT-scans.

    Science.gov (United States)

    Schumacher, K U; Koppe, T; Fanghänel, J; Schumacher, G H; Nagai, H

    1994-10-01

    The changes of the skull, which we can observe during the anthropogenesis, are reflected especially in the different skull proportions. We carried out metric measurements at the median level on 10 adult skulls each of humans, chimpanzees and gorillas as well as 11 skulls of orangutans. All skulls were scanned with a CT at the median level. We measured the lines and angles of the scans and the means and the standard deviations were calculated. We carried out a correlation analysis to observe the relation of their characteristics. We showed that there is a relation between the length of the skull base and the facial length in all species. From the results of the correlation analysis, we can also conclude that a relation exists between the degree of prognathism and the different length measurements of the facial skeleton. We also found a bending of the facial skeleton in relation to the cranial base towards the ventral side, also known as klinorhynchy, in all observed species. The highest degree of klinorhynchy was found in humans and the lowest in orangutans. We will discuss the different definition of the term klinorhynchy and its importance in the evolution of the hominoids.

  20. Sex determination of a Tunisian population by CT scan analysis of the skull.

    Science.gov (United States)

    Zaafrane, Malek; Ben Khelil, Mehdi; Naccache, Ines; Ezzedine, Ekbel; Savall, Frédéric; Telmon, Norbert; Mnif, Najla; Hamdoun, Moncef

    2017-09-21

    It is widely accepted that the estimation of biological attributes in the human skeleton is more accurate when population-specific standards are applied. With the shortage of such data for contemporary North African populations, it is duly required to establish population-specific standards. We present here the first craniometric standards for sex determination of a contemporary Tunisian population. The aim of this study was to analyze the correlation between sex and metric parameters of the skull in this population using CT scan analysis and to generate proper reliable standards for sex determination of a complete or fragmented skull. The study sample comprised cranial multislice computed tomography scans of 510 individuals equally distributed by sex. ASIR TM software in a General Electric TM workstation was used to position 37 landmarks along the volume-rendered images and the multiplanar slices, defining 27 inter-landmark distances. Frontal and parietal bone thickness was also measured for each case. The data were analyzed using basic descriptive statistics and logistic regression with cross-validation of classification results. All of the measurements were sexually dimorphic with male values being higher than female values. A nine-variable model achieved the maximum classification accuracy of 90% with -2.9% sex bias and a six-variable model yielded 85.9% sexing accuracy with -0.97% sex bias. We conclude that the skull is highly dimorphic and represents a reliable bone for sex determination in contemporary Tunisian individuals.

  1. Use of multiple CT scans to accommodate large objects and stretch dynamic range of detectability

    Energy Technology Data Exchange (ETDEWEB)

    Sivers, E.A.

    1994-09-01

    Rotate-only X-ray CT scanners are preferred for their speed and dose utilization, but suffer from the restriction that the scanned object must fit within the radiation beam. In addition, the ratio of signals unattenuated by air paths to those penetrating thick, dense objects often exceeds the dynamic range of conventional X-ray detectors. Both of these disadvantages can be removed for objects larger than the X-ray beam by taking multiple scans, each of which exposes only part of the object. These partial data sets can then be merged to produce a complete data set. For most objects, it is also possible to separately expose regions in which the ratios between the extremes of attenuation are much lower than that between air and the maximum path length. It is therefore possible to use a higher flux to image denser regions, improving signal-to-noise ratios and yielding images superior to those of larger scanners having the same dynamic range,

  2. 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.

  3. Partial scan artifact reduction (PSAR) for the assessment of cardiac perfusion in dynamic phase-correlated CT.

    Science.gov (United States)

    Stenner, Philip; Schmidt, Bernhard; Bruder, Herbert; Allmendinger, Thomas; Haberland, Ulrike; Flohr, Thomas; Kachelriess, Marc

    2009-12-01

    Cardiac CT achieves its high temporal resolution by lowering the scan range from 2pi to pi plus fan angle (partial scan). This, however, introduces CT-value variations, depending on the angular position of the pi range. These partial scan artifacts are of the order of a few HU and prevent the quantitative evaluation of perfusion measurements. The authors present the new algorithm partial scan artifact reduction (PSAR) that corrects a dynamic phase-correlated scan without a priori information. In general, a full scan does not suffer from partial scan artifacts since all projections in [0, 2pi] contribute to the data. To maintain the optimum temporal resolution and the phase correlation, PSAR creates an artificial full scan pn(AF) by projectionwise averaging a set of neighboring partial scans pn(P) from the same perfusion examination (typically N approximately 30 phase-correlated partial scans distributed over 20 s and n = 1, ..., N). Corresponding to the angular range of each partial scan, the authors extract virtual partial scans pn(V) from the artificial full scan pn(AF). A standard reconstruction yields the corresponding images fn(P), fn(AF), and fn(V). Subtracting the virtual partial scan image fn(V) from the artificial full scan image fn(AF) yields an artifact image that can be used to correct the original partial scan image: fn(C) = fn(P) - fn(V) + fn(AF), where fn(C) is the corrected image. The authors evaluated the effects of scattered radiation on the partial scan artifacts using simulated and measured water phantoms and found a strong correlation. The PSAR algorithm has been validated with a simulated semianthropomorphic heart phantom and with measurements of a dynamic biological perfusion phantom. For the stationary phantoms, real full scans have been performed to provide theoretical reference values. The improvement in the root mean square errors between the full and the partial scans with respect to the errors between the full and the corrected scans is

  4. 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.

  5. Evaluation of the CT dose index for scans with an ECG using a 320-row multiple-detector CT scanner

    International Nuclear Information System (INIS)

    Kobayashi, Masanao; Asada, Yasuki; Matsubara, Kosuke; Koshida, Kichiro; Suzuki, Shouichi; Matsunaga, Yuta; Kawaguchi, Ai; Haba, Tomonobu; Katada, Kazuhiro; Toyama, Hiroshi

    2015-01-01

    The relationship between heart rate (HR) and computed tomography dose index (CTDI) was evaluated using an electrocardiogram (ECG) gate scan for scan applications such as prospective triggering, Ca scoring, target computed tomography angiography (CTA), prospective CTA and retrospective gating, continuous CTA/CFA (cardiac functional analysis) and CTA/CFA modulation. Even in the case of a volume scan, doses for the multiple scan average dose were similar to those for CTDI. Moreover, it was found that the ECG gate scan yields significantly different doses. When selecting the optimum scan, the doses were dependent on many factors such as HR, scan rotation time, active time, pre-specified cardiac phase and modulation rate. Therefore, it is necessary to take these results into consideration when selecting the scanning parameters. (authors)

  6. 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

  7. 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…

  8. A case of multiple hepatic abscesses detected by CT scan in the patient with acute lymphoblastic leukemia

    International Nuclear Information System (INIS)

    Saburi, Yoshio; Shuto, Ryusuke; Mizutani, Ryoko; Hosokawa, Takafumi; Itoga, Takashi

    1983-01-01

    A 34 years old man admitted to a hospital on 21 Feb. 1983 and was diagnosed acute lymphoblastic leukemia. A hematological complete remission was achieved by combination therapy of vincristine, prednisolone and L-asparaginase. However, he had complaining of high fever and right hypochondralgia since early in Apr. 1983, and it was revealed that elevation of right diaphragm on chest X-ray. Therefore, he was also given several antibiotics (CPZ, TOB, LMOX, PIPC, LCM, AMK, MINO and GM) for complication of probable liver abscess. Remittent fever was persisted in spite of as mentioned above various antibiotics. The multiple hepatic abscesses were found by CT scan of the mid-abdomen as the low density lesions, but bacterial cultures detected no any pathogens. His complaining of remittent fever and right hypochondralgia were improved by treated with Miconazole during about one month, and decreasing in size and number of multiple hepatic abscesses were found by CT scan. Though we could not determined clearly, but suspected that, multiple hepatic abscesses were due to fungus infection, by reason of therapeutic result. Regarding the complication of hepatic abscesses with leukemia, 5 cases have been reported in Japan, and one case out of 5 cases were detected by CT scan. We thought that CT scan were useful procedure for a early diagnosis of hepatic abscesses. In recently, the patient has continued of complete remission hematologically. (author)

  9. Scatter radiation breast exposure during head CT: impact of scanning conditions and anthropometric parameters on shielded and unshielded breast dose

    International Nuclear Information System (INIS)

    Klasic, B.; Knezevic, Z.; Vekic, B.; Brnic, Z.; Novacic, K.

    2006-01-01

    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)

  10. 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)

  11. 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

    2011-05-01

    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.

  12. Is it possible to limit the use of CT scanning in acute diverticular disease without compromising outcomes? A preliminary experience.

    Science.gov (United States)

    Caputo, Pierpaolo; Rovagnati, Marco; Carzaniga, Pier Luigi

    2015-01-01

    The aim of our study was to determine whether the use of CT scanning in the assessment of acute diverticulitis can be reduced without a negative effect on outcome. Our series consisted of 93 out of 100 patients with acute diverticulitis admitted to the Emergency Room of our institution in the period from February 2012 to March 2013.The Hinchey classification system was used to stage disease based on findings on ultrasound (US) examination and/or computed tomography (CT) scanning. We compared the patients' Hinchey stage (HS) on admission and 72 hours later. Types of treatment were defined as emergency or delayed intervention (operative approaches (OA); ultrasound-guided percutaneous drainage (UPD), and surgery. The borderline between conservative and surgical management was identified. In patients with a HS CT scans. The skill of the individual operator in US examination was found to be of key importance. As regards CT scanning, we found, in agreement with the literature, that it has greater specificity and sensitivity than US, and is therefore indicated if the patient's condition has deteriorated.

  13. Triage of Limited Versus Extensive Disease on 18F-FDG PET/CT Scan in Small Cell lung Cancer

    Directory of Open Access Journals (Sweden)

    Saima Riaz

    2017-06-01

    Full Text Available Objective(s: Small cell lung cancer (SCLC is an aggressive neuroendocrine carcinoma, which accounts for 10-15% of pulmonary cancers and exhibits early metastatic spread. This study aimed to determine the added value of 18F-FDG PET/CT imaging in tumor, node, and metastasis (TNM staging of SCLC, compared to the conventional computed tomography (CT scan and its potential role as a prognosticator.Methods: This retrospective review was conducted on 23 patients, who were histopathologically diagnosed to have SCLC and referred for undergoing 18F-FDG PET/CT scanning during October 2009-December 2015. The rate of agreement between the CT and 18F-FDG PET/CT findings for TNM staging was calculated using the Cohen’s kappa (κ. The median follow-up time was eight months, ranging 27-3 months. The overall and disease-free survival rates were calculated based on the extent of disease.Results: 19 cases were male and four female with the mean age of 58±9 years. The 18F-FDG PET/CT identified limited and extensive diseases in 2 (8.7% and 21 (91.3% patients, respectively. In addition, the results of the Cohen’s kappa demonstrated a strong (κ=0.82, fair (κ=0.24, and poor (κ=0.12 agreement between the PET/CT and CT findings for determining tumor, node, and metastasis stages, respectively. The 18F-FDG PET/CT scans upstaged disease in 47% of the cases with visceral and osseous metastasis. The disease-free survival rates for the limited and extensive diseases were 100% and 23% within the 12-month follow-up. In addition, 8 (35% patients expired during the follow-up period.Conclusion: Improved nodal and metastatic disease identification highlights the role of 18F-FDG PET/CT scanning in initial staging of SCLC with prognostic implications.

  14. CT scan evaluation of glenoid bone and pectoralis major tendon: interest in shoulder prosthesis

    Science.gov (United States)

    Obert, Laurent; Peyron, Christelle; Boyer, Etienne; Menu, Gauthier; Loisel, François; Aubry, Sébastien

    2016-01-01

    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. PMID:27716461

  15. 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.

  16. Pre-treatment patient-specific stopping power by combining list-mode proton radiography and x-ray CT

    Science.gov (United States)

    Collins-Fekete, Charles-Antoine; Brousmiche, Sébastien; Hansen, David C.; Beaulieu, Luc; Seco, Joao

    2017-09-01

    The relative stopping power (RSP) uncertainty is the largest contributor to the range uncertainty in proton therapy. The purpose of this work was to develop a systematic method that yields accurate and patient-specific RSPs by combining (1) pre-treatment x-ray CT and (2) daily proton radiography of the patient. The method was formulated as a penalized least squares optimization problem (argmin(\\Vert {A}{x}-{b}\\Vert _22 )). The parameter A represents the cumulative path-length crossed by the proton in each material, separated by thresholding on the HU. The material RSPs (water equivalent thickness/physical thickness) are denoted by x. The parameter b is the list-mode proton radiography produced using Geant4 simulations. The problem was solved using a non-negative linear-solver with {x}≥slant0 . A was computed by superposing proton trajectories calculated with a cubic or linear spline approach to the CT. The material’s RSP assigned in Geant4 were used for reference while the clinical HU-RSP calibration curve was used for comparison. The Gammex RMI-467 phantom was first investigated. The standard deviation between the estimated material RSP and the calculated RSP is 0.45%. The robustness of the techniques was then assessed as a function of the number of projections and initial proton energy. Optimization with two initial projections yields precise RSP (⩽1.0%) for 330 MeV protons. 250 MeV protons have shown higher uncertainty (⩽2.0%) due to the loss of precision in the path estimate. Anthropomorphic phantoms of the head, pelvis, and lung were subsequently evaluated. Accurate RSP has been obtained for the head (μ =0.21+/-1.63% ), the lung (μ=0.06+/-0.99% ) and the pelvis (μ=0.90+/-3.87% ). The range precision has been optimized using the calibration curves obtained with the algorithm, yielding a mean R80 difference to the reference of 0.11  ±0.09%, 0.28  ±  0.34% and 0.05 +/- 0.06% in the same order. The solution’s accuracy is limited by the

  17. Pre-treatment patient-specific stopping power by combining list-mode proton radiography and x-ray CT.

    Science.gov (United States)

    Collins-Fekete, Charles-Antoine; Brousmiche, Sébastien; Hansen, David C; Beaulieu, Luc; Seco, Joao

    2017-08-03

    The relative stopping power (RSP) uncertainty is the largest contributor to the range uncertainty in proton therapy. The purpose of this work was to develop a systematic method that yields accurate and patient-specific RSPs by combining (1) pre-treatment x-ray CT and (2) daily proton radiography of the patient. The method was formulated as a penalized least squares optimization problem (argmin([Formula: see text])). The parameter A represents the cumulative path-length crossed by the proton in each material, separated by thresholding on the HU. The material RSPs (water equivalent thickness/physical thickness) are denoted by x. The parameter b is the list-mode proton radiography produced using Geant4 simulations. The problem was solved using a non-negative linear-solver with [Formula: see text]. A was computed by superposing proton trajectories calculated with a cubic or linear spline approach to the CT. The material's RSP assigned in Geant4 were used for reference while the clinical HU-RSP calibration curve was used for comparison. The Gammex RMI-467 phantom was first investigated. The standard deviation between the estimated material RSP and the calculated RSP is 0.45%. The robustness of the techniques was then assessed as a function of the number of projections and initial proton energy. Optimization with two initial projections yields precise RSP (⩽1.0%) for 330 MeV protons. 250 MeV protons have shown higher uncertainty (⩽2.0%) due to the loss of precision in the path estimate. Anthropomorphic phantoms of the head, pelvis, and lung were subsequently evaluated. Accurate RSP has been obtained for the head ([Formula: see text]), the lung ([Formula: see text]) and the pelvis ([Formula: see text]). The range precision has been optimized using the calibration curves obtained with the algorithm, yielding a mean [Formula: see text] difference to the reference of 0.11  ±0.09%, 0.28  ±  0.34% and [Formula: see text] in the same order. The solution

  18. Can postoperative complications be predicted by a routine CT scan on day 5? A study of 78 laparoscopic colorectal resections.

    Science.gov (United States)

    Wagner, M; Zappa, M; Maggiori, L; Bretagnol, F; Vilgrain, V; Panis, Y

    2014-03-01

    Postoperative computed tomography (CT) scan patterns after colorectal resection are difficult to analyze for both clinicians and radiologists. This study aimed to assess the role of single CT scan on postoperative day 5 in predicting postoperative morbidity. From October 2007 to August 2009, 78 patients undergoing laparoscopic colorectal resection were enrolled in a research study involving a routine contrast-enhanced multi-detector CT scan on postoperative day 5. Two groups were defined: patients with intra-abdominal postoperative morbidity requiring specific management, i.e., surgical or radiological procedure, and/or antibiotic therapy ("complications" group), and patients with uneventful postoperative outcome ("uneventful" group). CT findings were compared between the two groups with Fisher's exact test or chi-square test. Postoperative abdominal complications occurred in 16 patients (21 %). Of the CT findings on day 5, pneumonia, pulmonary embolism, portal or mesenteric thrombosis, operative area fat infiltration, peritoneal effusion, pneumoperitoneum, intra-abdominal collection, parietal inflammation or collection, and subcutaneous emphysema were observed in both groups without any significant difference. Only small bowel distension [25 % (4/16) in the "complications" group vs. 5 % (3/62) in the "uneventful" group; p = 0.029] and pleural effusion [81 % (13/16) vs. 48 % (30/62); p = 0.024, respectively] were observed significantly more often in the "complications" group. This study suggested that abdominal complications cannot be predicted by a CT scan on day 5 after laparoscopic colorectal resection. Thus, it cannot be recommended for routine use.

  19. 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...

  20. A clinical study of major stroke cases of a low-perfusion pattern on a dynamic CT scan

    International Nuclear Information System (INIS)

    Shimada, Tsutomu; Kaneko, Mitsuo; Tanaka, Keisei; Sugiura, Masashi

    1986-01-01

    Preoperative dynamic CT scans have been done for the past 4 years in order to estimate the degree of ischemia in the region responsible. The hemodynamic patterns on the dynamic CT scans were consequently classified into three particular types: Type 1: The collateral flow was preserved considerably, and the peak value of the time-density curve exceeded 50 % of the opposite healthy side. Type 2: The residual flow was moderate, and the peak value was approximately from one-third to one-half of the normal side. Type 3: The residual flow was minimal, and the time-density curve was almost flat or the peak value did not reach even approximately one-third of the opposite side. In general, major stroke cases with a Type 1 pattern on the dynamic CT scan showed a considerably good recovery if the revascularization was completed within 6 hours after the attack. However, cases of the Type 3 pattern often developed into a massive cerebral infarction associated with a marked mid-line shift, and sometimes they were fulminent even after acute revascularization. In this paper, clinical results of 11 major stroke cases with the Type 2 pattern on dynamic CT scans were evaluated. All of them showed hemiplegia, with or without aphasia, just after the onset of the stroke, and dynamic CT scans were performed within 24 hours. The site of the occluded vessel was in the internal carotid artery (ICA) in 4 cases and in the middle cerebral artery (MCA) in 6; severe stenosis in ICA and MCA was found in only one case. The functional recovery was rather poor. Only one was capable of self-care at home; four others required partial care at home, and the other six were bed-ridden. In the 4 surgical cases of acute revascularization, the clinical symptoms did not improve, and the functional recovery was almost equivalent to the natural course. (J.P.N.)

  1. Evaluation of diagnostic reference dose levels in CT- scan examinations of adolescence in Tehran: a brief report

    Directory of Open Access Journals (Sweden)

    Afzalipour R

    2013-05-01

    Full Text Available Background: Today, a CT scan examination play an important role in disease diagnosis and thus allocates a significant dose of medical X-ray examinations. One of the important principles in the use of ionizing radiations is to observe radiation protection principles. Evaluating patient's absorbed dose and implementing the strategies for reducing dose are prior in safety issues. To achieve this purpose, sufficient studies should be performed in this regard. Therefore, patient's absorbed dose and the factors affecting have been studied in this research. This study aims to present and develop an acceptable level of absorbed dose in CT scan examinations.Methods: Diagnostic reference dose level in the adult age group (older than 15 years has been studied in ele