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Sample records for ct scan showed

  1. Head CT scan

    Science.gov (United States)

    Brain CT; Cranial CT; CT scan - skull; CT scan - head; CT scan - orbits; CT scan - sinuses; Computed tomography - cranial; CAT scan - brain ... hold your breath for short periods. A complete scan usually take only 30 seconds to a few ...

  2. CT scan of choristoma

    Energy Technology Data Exchange (ETDEWEB)

    Moriki, A.; Morimoto, M.; Sada, Y.; Kurisaka, M.; Mori, K.

    1987-02-01

    Choristoma is a rare tumor that occurs in the pituitary gland. The case presented here is a 44-year-old male. A plain CT scan demonstrated a slight high-density mass near the posterior clinoid of the sella turcica, while a moderate and homogeneous enhancing effect and a clear borderline were shown by an enhanced CT scan. A cornal CT scan study showed that the tumor extended from the intrasellar to the suprasellar region. The diagnosis of choristoma was made by means of histology.

  3. Lumbar spine CT scan

    Science.gov (United States)

    CAT scan - lumbar spine; Computed axial tomography scan - lumbar spine; Computed tomography scan - lumbar spine; CT - lower back ... your breath for short periods of time. The scan should take only 10 to 15 minutes.

  4. 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.

  5. Cervical spine CT scan

    Science.gov (United States)

    ... defects of the cervical spine Bone problems Fracture Osteoarthritis Disc herniation Risks Risks of CT scans include: ... Ma, MD, Assistant Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, ...

  6. Chest CT Scan

    Science.gov (United States)

    ... can combine these pictures to create three-dimensional (3D) models to help show the size, shape, and ... a medical imaging facility or hospital. The CT scanner is a large, tunnel-like machine that has ...

  7. Technical aspects of CT scanning.

    Science.gov (United States)

    Maravilla, K R; Pastel, M S

    1978-01-01

    The advent of computed tomography (CT) has initiated a technological revolution which continues to the present time. A brief review of basic principles of CT scanning is presented, and the evolution of modern CT scanner systems is traced. Some early indications of future trends are also presented.

  8. Cardiac CT Scan

    Science.gov (United States)

    ... combine these pictures to create a three-dimensional (3D) model of the whole heart. This imaging test ... findings from earlier chest x rays. Different CT scanners are used for different purposes. A multidetector CT ...

  9. Body CT (CAT Scan)

    Science.gov (United States)

    ... You may also be asked to remove hearing aids and removable dental work. Women will be asked to remove bras ... and surgical biopsy. No radiation remains in a patient's body after a CT ... side effects. Risks There is no conclusive evidence that radiation at ...

  10. CT scan correlates of gesture recognition.

    Science.gov (United States)

    Ferro, J M; Martins, I P; Mariano, G; Caldas, A C

    1983-10-01

    The ability to recognise gestures was studied in 65 left-hemispheric stroke patients whose lesions were located by CT scan. In the acute stage (first month) frontal lobe and basal ganglia were frequently involved in patients showing inability to recognise gestures. In the later (third to fourth month) and chronic stages (greater than 6 months) parietal lobe involvement was important; lesions causing gesture recognition impairment were larger, had more extensive and frequent parietal involvement and produced less temporal lobe damage than those causing aural comprehension defects. These findings are discussed in the light of recent models of cerebral localisation of complex functions.

  11. Diagnosis of pituitary microadenomas by CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Sakoda, K.; Gen, M.; Yonezawa, M.; Ohta, M.; Matsumura, S. (Hiroshima Univ. (Japan). School of Medicine)

    1981-10-01

    The presence of pituitary microadenomas can be established by the detection of minor changes on polytomograms of the sella turcica. However, as this method is a procedure for detecting secondary changes due to adenoma, it is understandable that microadenomas which fail to present secondary changes cannot be picked up. From this point of view, we investigated the possibility detecting changes in the pituitary itself by means of CT. An axial scan of pituitary microadenomas by EMI-1010 showed that some of the PRL secreting adenomas and all of the GH secreting adenomas showed areas of high density, and that some of PRL secreting adenomas and all the ACTH secreting adenomas showed areas of low density at the site of the adenomas. On a coronal scan with GE/X2, the normal pituitary is highly enhanced, and an absorption coefficient of 70 - 80 is demonstrated, but on an axial scan the coefficient becomes 25 - 35 due to the partial-volume effect. On a coronal scan pituitary microadenomas are shown as hypodense-lucent or isodense as a normal pituitary. However, the absorption coefficient of the hypodense-lucent area was 50 - 60; this is not low, but is, rather, a high density. At present, it is our belief that it is most effective to use a coronal angle with a high-resolution scanner in the diagnosis of pituitary microadenomas.

  12. Evaluation strategies in CT scanning

    DEFF Research Database (Denmark)

    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...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1992-05-01

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

  14. 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...... knowledge about the weight of other tissue types from CT. Knowing the weight of individual tissue types will directly give access to other measures such as the weight of the carcass and the Lean Meat Percentage (LMP). Until now, most analyses of CT scans have been based on the Hounsfield spectra that does...... 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....

  15. 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.

  16. Indications for CT scanning in minor head injuries: a review.

    Science.gov (United States)

    Żyluk, Andrzej

    2015-01-01

    To determine indications for performing head CT following minor head injuries, which allow reducing number of imaging. Based on 15 articles dedicated to this topic, the clinical decision rules were systematically analysed. The Canadian Computed Tomography Head Rule was found to be the most reliable instrument meeting these criteria, characterised by excellent sensitivity of 100% and fairly good specificity of 48-77%. Remaining scales, although very sensitive, showed poor ability to reduce number of "unnecessary" CT scans. Features most predictive for intracranial injuries included: disorientation, abnormal alertness, somnolentia and neurological deficits. Patients with no loss of consciousness and in normal physical condition need only clinical assessment. Indications to head CT scanning are determined by decision rules presented in the article. Use of clinical decision rules may have effect on reducing number of head CT scanning performed "just in a case". Copyright © 2015 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  17. 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.

  18. Thin-section CT scan of the pituitary gland

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, T.; Inoue, Y.; Taniguchi, S. (Osaka City Univ. (Japan). Faculty of Medicine)

    1982-02-01

    Topographic anatomy of the pituitary fossa was studied by 2 mm thin-section CT scan (Somatom II). Nineteen with normal pituitary (control group) and 20 with suspected pituitary abnormality were selected. Plain and contrast CT were performed in all cases. Contrast CT was carried out immediately after the rapid infusion of 220 ml of 30% iodinated contrast medium. In all of control group but two, pituitary gland was detected as homogeneous density and its density was the same as the density of normal brain tissues, and was enhanced in degree of about 25 CT number. In 2 cases, small low density was visualized in the pituitary gland. Pituitary gland was differentiated from cavernous sinus was usually higher than the pituitary gland. In the abnormal group, microadenoma of the pituitary gland was diagnosed in 5 cases and 3 out of 5 cases was proved by surgery. All 3 microadenomas proved slightly dense by plain CT and enhanced higher than normal pituitary gland by contrast CT. Polytomograms showed no abnormality of the sella turcica in one of these 3 cases. Although 3 microadenomas were detected by the abnormal enhancement, we are not sure whether all microadenoma can be detected by CT alone. Arachnoid herniation into the pituitary fossa was diagnosed in 7 of the control group and 2 of the abnormal group. Four out of these 9 cases were verified by using Metrizamide CT. By plain thin-section CT, the diagnosis of arachnoid herniation seems to be possible without Metrizamide CT.

  19. Neurological ct Scan Value for Ictus in Cienfuegos Province

    Directory of Open Access Journals (Sweden)

    Idaylí Pérez Rodríguez

    2007-05-01

    Full Text Available Backgrounds: CT scan constitutes a very important technique in the diagnosis of the cerebrovascular disease. The impact this transcendental event had and will continue having in the medicine area is impossible to state in terms of dimensions during the next years. Objective: To determine the neurological CT scan value for ictus in our milieu. Methods: A retrospective, prospective, longitudinal study of a series of cases performed during a review of statistical reports as well as that of Stroke data base which stores information of patients with neurocitus in our province, and which is based on others aspects founds by means of neurological CT scan. Results: CT scan allowed us to diagnose the type of cerebrovascular event (75.55 % ischemic events, 24.45% hemorrhagic events. It also contributed to the necessary data such as the localization (with predominium of 35.55% in more than one area, and 7.40 % in the parietal area. The presence of cerebral edema was verified in 16.29% of the cases as well as displacement of the midline in 7.40 % both associated to a torpid evolution. It incorporated the Fisher and Le Roux scales showing their prognosis value with elevated measures for deceased patients and decreased values for survivors without disability. Conclusions: The diagnosis and prognosis value were proved as well as CT scan behavior in our milieu. These aspects permit the reliable introduction of new therapeutic modalities in our province.

  20. 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.).

  1. CT scan findings in cerebral paragonimiasis

    Energy Technology Data Exchange (ETDEWEB)

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

    1982-12-01

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

  2. 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....

  3. Acquired tracheomalacia: detection by expiratory CT scan.

    Science.gov (United States)

    Aquino, S L; Shepard, J A; Ginns, L C; Moore, R H; Halpern, E; Grillo, H C; McLoud, T C

    2001-01-01

    The purpose of this work was to determine whether cross-sectional area and coronal and sagittal diameter measurements of the trachea between inspiration and end-expiration on CT are significantly different between patients with acquired tracheomalacia and those without this condition. Inspiratory and end-expiratory CT scans of the trachea of 23 normal patients and 10 patients with acquired tracheomalacia were analyzed. Percent changes in cross-sectional area, coronal, and sagittal diameters were calculated. For patients with tracheomalacia, mean percent changes in the upper and middle trachea between inspiration and expiration were 49 and 44%; mean changes in the coronal and sagittal diameters in the upper and middle tracheal were 4 and 10% and 39 and 54%, respectively. Control group mean percent changes in the upper and middle tracheal area were 12 and 14%, respectively, and mean changes in the coronal and sagittal diameters in the upper and middle trachea were 4 and 4% and 11 and 13%, respectively. Significant differences were calculated for changes in cross-sectional area and sagittal diameter between groups (p 18% change in the upper trachea and 28% change in the midtrachea between inspiration and expiration were observed; the probability of tracheomalacia was 89-100%. The probability of tracheomalacia was > 89%, especially if the change in sagittal diameter was > 28%. By measuring changes in tracheal cross-sectional area and sagittal diameters between inspiratory and end-expiratory CT, a significant difference can be identified between normal patients and those with acquired tracheomalacia.

  4. 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.

  5. 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.

  6. 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.

  7. Leigh syndrome. A comparison of CT scanning and pathological findings

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, Y.; Okamoto, K.; Somiya, K. (Hamamatsu Medical Center, Shizuoka (Japan)); Hokazono, Y.; Tozuka, S.

    1981-11-01

    A male infant developed hypotonia at 5 months, vomiting, diarrhea, fever, generalized clonic convulsion, tonic spasm and periodical opisthotonus at 8 months, swallowing difficulty at 10 months, pes equinovarus and optic atrophy at 11 months, and then tachypnea, and died at 14 months of age. Parents were consanguinous. Laboratory studies revealed elevated serum LDH, CPK, lactate and Pyruvate. TPP-ATP phosphoryl transferase inhibitor was negative in urine. EEG showed irregular and diffuse slow waves and periodic diffuse spike and waves. CT scan at 9 months of age showed slightly low attenuation areas in the putamen bilaterally. At 11 months, a diffuse cerebral atrophy was found, and the low attenuation of the basal ganglia became more definite. No enhanced lesion was seen at 13 months of age. Thiamine tetra-hydrofurfuryl disulfide and lipoic acid were tried without success. The pathological findings of the brain were astrogliosis and proliferation of capillaries in putamen, thalamus, caudate nucleus, substantia nigra, pontine brachium and cerebral cortex, which were symmetrically involved. The symmetrical cavitation was found in putamen. Optic nerve and mamillary body were spared. CT scan findings corresponded well with the pathology of the necrotic lesions of the brain. It was concluded that these CT scan pictures described above may be diagnostic of Leigh syndrome.

  8. Segmentation of anatomical structures in chest CT scans

    NARCIS (Netherlands)

    van Rikxoort, E.M.

    2009-01-01

    In this thesis, methods are described for the automatic segmentation of anatomical structures from chest CT scans. First, a method to segment the lungs from chest CT scans is presented. Standard lung segmentation algorithms rely on large attenuation differences between the lungs and the surrounding

  9. Automatic segmentation of pulmonary segments from volumetric chest CT scans.

    NARCIS (Netherlands)

    Rikxoort, E.M. van; Hoop, B. de; Vorst, S. van de; Prokop, M.; Ginneken, B. van

    2009-01-01

    Automated extraction of pulmonary anatomy provides a foundation for computerized analysis of computed tomography (CT) scans of the chest. A completely automatic method is presented to segment the lungs, lobes and pulmonary segments from volumetric CT chest scans. The method starts with lung segmenta

  10. Evolving brain lesions in the follow-up CT scans 12 h after traumatic brain injury

    Institute of Scientific and Technical Information of China (English)

    Muhammad Sohail Umerani; Asad Abbas; Saqib Kamran Bakhshi; Ujala Muhammad Qasim; Salman Sharif

    2016-01-01

    Objective: To establish the frequency of evolution in CT appearance from an initial scan to a subsequent scan within 12 h and the prognostic significance of such deterioration. Methods: All patients who presented to Department of Neurosurgery, Liaquat National Hospital and Medical College with traumatic brain injury and received their CT scan within the first 4 h of injury were included in the study. Indications for repeat CT scan were: any deterioration in neurological status after the initial scan, potentially deterio-rating lesion on initial scan with or without worsening neurology, worsening neurological status after the initial CT scan findings, or no neurological improvement after initial management in patients with normal CT scan with significant head injury. This compiled with the data of 107 patients. Results: There were 67 males and 40 females. The cause of trauma of the 70%patients was road traffic accident. In 11 patients, the lesion evolved towards resorption while 32 patients had no significant changes in the subsequent CT scan. Sixty four patients showed an increase in the size of the lesion and 65.6%of them were required surgical intervention subsequently. Conclusions: In case where the initial CT scan performed within 4 h of significant head injury was not correlated with the patient's neurology, it should be repeated within 12 h.

  11. Diagnostic accuracy of CT scan in abdominal blunt trauma

    Institute of Scientific and Technical Information of China (English)

    Javad Salimi; Khadyjeh Bakhtavar; Mehdi Solimani; Patrcia Khashayar; Ali Pasha Meysamie; Moosa Zargar

    2009-01-01

    Obiective: To evaluate the sensitivity and specificity of CT scan findings in Patients ith blunt abdominal trauma admitted to the university hospital.Methods: All the atients ith blunt abdominal trauma admitted at a tertiary teaching trauma center in Iran between 2005 and 2007 were enrolled in this study.In the absence of any clinical anifestations,he patients underwent a diagnostic CT scan.Laparatomy was performed in those with positive CT results.Others were observed for 48 hours and discharged in case no problem as reported;otherwise they underwent laparatomy.Information on patients'demographic ata,mechanism of trauma,indication for CT scan,CT scan findings,results of laparotomy ere gathered.The sensitivity,specificity and accuracy of the CT-scan images in regard ith the organ injured were calculated.The sensitivity,specificity and accuracy of the T scan were calculated in each case.Results: CT Scan had the highest sensitivity for etecting the injuries to liver (100%) and spleen (86.6%).The specificity of the method or detecting retroperitoneal hematoma (100%) and injuries to kidney (93.5%) was higher han other organs.The accuracy of CT images to detect the injuries to spleen,liver,idney and retroperitoneal hematoma was reported to be 96.1%,94.4%,91.6% and 91.6% espectively.Conclusion: The findings of the present study reveal that CT scan could econsidered as a good choice,especially for patients with blunt abdominal trauma in eaching hospitals where the radiologic academic staff is not present in the hospital in the night shifts.

  12. CT scan of the hypopharynx and larynx. Value of phonation scans

    Energy Technology Data Exchange (ETDEWEB)

    Fujii, Naoko; Anno, Hirofumi; Takahashi, Masaki; Koga, Sukehiko; Mori, Shigeki; Iwata, Shigenobu; Ikuta, Katsumi; Mashita, Shinichi.

    1988-08-01

    29 patients with hypopharyngeal or laryngeal disorders were sustained phonation of vowel /E/ at their comfortable pitch and intensity levels on their CT scans. These images were compared with CT scans during quiet breathing or breath holding. The pyriform sinuses and the aryepiglottic folds were better visualized and the details of the glottis and the laryngeal ventricles were demonstrable during phonation.

  13. Solitary pulmonary granuloma with marked enhancement on dynamic CT scanning

    Energy Technology Data Exchange (ETDEWEB)

    Stark, P.; Wong, V.; Gold, P.

    1988-10-01

    A patient is described who presented with a vividly enhancing solitary pulmonary nodule during dynamic CT scanning. This mass proved to represent a granuloma due to coccidioidomycosis. The presumptive mechanism of enhancement as well as the differential diagnosis are discussed.

  14. CT Scans Might Help Gauge Heart Attack Risk

    Science.gov (United States)

    ... html CT Scans Might Help Gauge Heart Attack Risk Researchers aim to identify vulnerable patients before damage becomes irreversible To use ... significantly narrowed, Antoniades said. No currently available test identifies ... journal Science Translational Medicine . About 750,000 Americans have ...

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

    NARCIS (Netherlands)

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

    2012-01-01

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

  16. Abdominal CT scanning in critically ill surgical patients.

    Science.gov (United States)

    Norwood, S H; Civetta, J M

    1985-01-01

    Clinical parameters, intensive care unit (ICU) course, abdominal computed tomography (CT) scans, and the clinical decisions of 53 critically ill patients were reviewed to determine the influence of the CT scan. No scans were positive before the eighth day. Sensitivity was 48% and specificity, 64%. Seventeen (23%) scans of the 72 provided beneficial results: eight localized abscesses that were drained; nine were negative and not operated on. Five (7%) scans provided detrimental information: scan negative with abscess discovered or scan positive but negative laparotomy. Fifty (70%) scans were either of no help or not used in management. The mortality rate was 50% when CT led to an intervention, and 47% in the entire group. Hospital charges were +33,408. Personnel time and cost were 497 hours and +3658; of the total +37,066, 77% (+28,541) could be considered wasted. From these data, it was concluded that CT scans should be used to confirm abscesses, not to search for a source of sepsis. PMID:4015222

  17. Optimized Temporal Window for Detection and Characterization of Renal Cell Carcinomas with Dynamic CT Scanning

    Institute of Scientific and Technical Information of China (English)

    Jinhong Wang; Peijun Wang; Xiaohu Zhao; Xinqin Mao; Xiaolong Gao; Jun Liu

    2005-01-01

    OBJECTIVE To investigate the optimized time period for detection and characterization of renal cell carcinomas (RCC) when the specific CT features appear during spiral dynamic CT scanning, and to optimize an effective scanning protocol of spiral CT for evaluating RCC.METHODS Twenty-four patients with RCC verified by pathology had undergone a dynamic CT (D-CT) scan. A plain scan was employed to select the target slice. Single-level dynamic scanning started at 14-17 s after the intravenous contrast media had been administered, with a scan interval of 4.9 s acquiring a total number of 17~24 frames. A regular CT scan of the whole kidney followed by a delayed single slice acquisition through the target slice in the excretory phase was performed. Images were assessed in two ways: (1) A group of experienced radiologists reviewed the CT images to find when the specific signs appeared and when the CT features of RCC were optimally displayed; (2) Data measurement of the time-density curves (T-DC) of RCC. The exact time was obtained when the densities of the tumor, renal parenchyma, medulla and aorta reached their peak enhancement, thus also the time when the density difference between tumor and parenchyma was at maximum (Max T-M). Based on the slope of the contrast media uptake curve, T-DC types were ranked from the smallest to the biggest of slope as type A, B and C.RESULTS 1. The review of the CT images by the radiologists showed that the CT features of RCC were optimally demonstrated at 70.2 s. The earliest time at which RCC CT features were examined was at 23.9 s. 2. Image data analysis: the time that the density (or CT value) of the tumor mass reached peak enhancement was at 54 s and peak value was at 80.4 Hu for RCC. The time of the maximal difference of densities between tumor and renal parenchyma was at 102 s.CONCLUSION The following proposal is the scanning protocol for detecting RCC recommended by our research: After a plain scan to determine the target level, a

  18. 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)

  19. Hybrid detection of lung nodules on CT scan images

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-09-15

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

  20. An evaluation of cranial CT scanning in clinical psychiatry.

    Science.gov (United States)

    Colohan, H; O'Callaghan, E; Larkin, C; Waddington, J L

    1989-07-01

    From 6,300 psychiatric admissions over a 37 month period, all 54 patient referrals for CT were identified and their charts reviewed. CT influenced diagnosis, management or prognosis in 11.7 percent of patients scanned. There was poor correlation between organicity on CT scan and findings on physical examination, laboratory testing, EEG and psychological testing. The mental state examination was the single significant correlate of CT abnormality. We suggest that the use of a formalised mental state examination such as the Mini Mental State, in addition to the usual clinical assessment of mental state, may improve the accuracy of prediction of abnormality on CT scan. The introduction of X-ray computed tomography (CT) is recognised to be one of the most important innovations in the recent history of clinical medicine. In neurology the value of a non-invasive technique for examining the intracranial contents was quickly realised in the areas of diagnosis, particularly in the detection of vascular accidents and tumours. CT has also attained a significant place in psychiatry. In research studies, it has provided important information on schizophrenia, alcoholism and chronic organic reactions. The place of CT in clinical psychiatry is less clear. As its availability has increased, such scans are being requested with increasing frequency in psychiatric patients. Cranial CT is a highly sensitive diagnostic procedure which, when used unselectively, may result in the discovery of incidental findings. Until recently, a function of the psychiatrist in relation to diagnosis was to first seek to distinguish symptoms produced by organic pathology from those produced by functional illness.(ABSTRACT TRUNCATED AT 250 WORDS)

  1. CT scan of the brain (image)

    Science.gov (United States)

    ... CAT scan (computed tomography) is a much more sensitive imaging technique than x-ray, allowing high definition not only of the bony structures, but of the soft tissues. Clear images of organs such as the brain, muscles, joint structures, veins ...

  2. A low density area along the ventricular catheter on CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Yasuo; Ishii, Ryoji; Watanabe, Akira; Hirano, Kazuhiro; Kamada, Masaki; Okamura, Hironari (Kawasaki Medical School, Kurashiki, Okayama (Japan))

    1990-12-01

    Ten patients with hydrocephalus due to various causes, such as subarachnoid or intraventricular hemorrhage, had low density area (LDA) along the ventricular catheter on CT scans. This is an analysis of the 10 patients, with a discussion of the etiology. Ventriculoperitoneal (VS) shunt was performed in 8 patients, and 3 underwent ventricular drainage. None of the patients had postoperative hemorrhage. According to CT findings, the patients were divided into three groups. The first group consisted of 3 patients whose CT scans showed progressive ventricular dilatation and a presence of LDA along the ventricular catheter. After surgical resolution of high intraventricular pressure, repeated CT scans showed a remarkably decreased ventricles and LDA. In this group, an increased intraventricular pressure may play an important role in the formation of LDA. In the second group consisting of 3 patients, there was no postoperative CT evidence of progressive ventricular dilatation, but LDA was present. Follow-up CT scans revealed a decreased lesion. A slightly increased intraventricular pressure may result in LDA. In the last group of 4 patients, CT scans showed a small, irregular, marginal LDA along the ventricular catheter, with no evidence of increased ventricle. On repeated CT scans after conservative treatment, the lesion persisted for several years after VP shunt. There was a good correlation between CT findings and patient age. Children seemed to have a large porencephalic cyst. In conclusion, LDA may be an accumulation of CSF within the unresisting white matter along the ventricular catheter due to increased intraventricular pressure. Various CT patterns seem to depend on the increased degree of intraventricular pressure and the compliance of the surrounding white matter. (N.K.).

  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. Cerebellopontine angle epidermoid showing a positive enhancement upon metrizamide CT cisternography

    Energy Technology Data Exchange (ETDEWEB)

    Hasegawa, Takeshi; Wakamatsu, Koichi; Fujii, Toshiharu; Ito, Haruhide; Yamamoto, Shinjiro; Nagata, Izumi

    1985-04-01

    A case of epidermoid tumor in the left cerebellopontine angle cistern is reported in a 43-year-old woman with left trigeminal neuralgia. Plain CT scan revealed a low density area at the left cerebellopontine angle and left ambient cisterns, which could not be differentiated from their enlargement. Metrizamide CT cisternography showed an irregular, high density pattern in the low density filling defect which was extending into the suprasellar and interpeduncular cisterns. The developmental mechanism of this specific finding in the metrizamide CT cisternography was discussed on the basis of morphological characteristics of epidermoid tumor.

  5. 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......, and are adapted to use neighbourhood information in 2D and 3D. Articial Poisson noise is added to the provided dataset to determine how well each of the methods handles noise. Good noise handling will allow lower dose scannings. The investigated methods did not perform better than the reference model in terms...

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-03-01

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

  7. Incidental Findings on CT Scans in the Emergency Department

    Directory of Open Access Journals (Sweden)

    Ryan J. Thompson

    2011-01-01

    Full Text Available Objectives. Incidental findings on computed tomography (CT scans are common. We sought to examine rates of findings and disclosure among discharged patients who received a CT scan in the ED. Methods. Retrospective chart review (Aug-Oct 2009 of 600 patients age 18 and older discharged home from an urban Level 1 trauma center. CT reports were used to identify incidental findings and discharge paperwork was used to determine whether the patient was informed of these findings. Results. There were 682 CT scans among 600 patients: 199 Abdomen & Pelvis, 405 Head, and 78 Thorax. A total of 348 incidental findings were documented in 228/682 (33.4% of the scans, of which 34 (9.8% were reported to patients in discharge paperwork. Patients with 1 incidental finding were less likely to receive disclosure than patients with 2 or more (=.010. Patients age <60 were less likely to have incidental findings (<.001. There was no significant disclosure or incidental finding difference by gender. Conclusions. While previous research suggests that CT incidental findings are often benign, reporting to patients is recommended but this is rarely happening.

  8. Clinical evaluation of dynamic CT scan of the pancreas

    Energy Technology Data Exchange (ETDEWEB)

    Tokuda, Masamichi

    1984-09-01

    The clinical usefulness of dynamic CT scans (DCT) of the pancreas was evaluated in 62 normal cases, 9 cases of acute pancreatitis, 24 cases of chronic pancreatitis and 43 cases of carcinoma of the pancreas. The normal pancreas was intensely and homogeneously enhanced on DCT, and peripancreatic vessels were clearly demonstrated, especially the gastroduodenal artery (98.4%). DCT was useful to demonstrate vascular lesions, associated with pancreatitis such as pseudoaneurysm. Although the carcinoma of the pancreas showed poor contrast enhancement on conventional enhanced CT (CCT), 37.2% showed intense contrast enhancement on DCT. Visualization of the gastroduodenal artery by DCT is helpful to decide the extent of tumor. DCT is superior to CCT in demonstrating collateral veins caused by tumor invasion to the portal system in carcinoma. DCT was approximately as accurate as angiography (92.6%) in evaluating tumor invasion to the portal system. DCT is a useful and minimally invasive modality in assessing the resectability of pancreatic carcinoma. DCT may eliminate angiography and surgery in unresectable cases. (author).

  9. Autopsied case of tuberculous meningitis showing interesting CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Abiko, Takashi; Higuchi, Hiroshi; Imada, Ryuichi; Nagai, Kenichi (Iwate Prefectural Central Hospital (Japan))

    1983-11-01

    A 61-year-old female patient died of a neurological disorder of unknown origin one month after the first visit and was found to have had tuberculous meningitis at autopsy. CT revealed a low density area showing an enlargement of the cerebral ventricle but did not reveal contrast enhancement in the basal cistern peculiar to tuberculous meningitis.

  10. Automated lung segmentation of low resolution CT scans of rats

    Science.gov (United States)

    Rizzo, Benjamin M.; Haworth, Steven T.; Clough, Anne V.

    2014-03-01

    Dual modality micro-CT and SPECT imaging can play an important role in preclinical studies designed to investigate mechanisms, progression, and therapies for acute lung injury in rats. SPECT imaging involves examining the uptake of radiopharmaceuticals within the lung, with the hypothesis that uptake is sensitive to the health or disease status of the lung tissue. Methods of quantifying lung uptake and comparison of right and left lung uptake generally begin with identifying and segmenting the lung region within the 3D reconstructed SPECT volume. However, identification of the lung boundaries and the fissure between the left and right lung is not always possible from the SPECT images directly since the radiopharmaceutical may be taken up by other surrounding tissues. Thus, our SPECT protocol begins with a fast CT scan, the lung boundaries are identified from the CT volume, and the CT region is coregistered with the SPECT volume to obtain the SPECT lung region. Segmenting rat lungs within the CT volume is particularly challenging due to the relatively low resolution of the images and the rat's unique anatomy. Thus, we have developed an automated segmentation algorithm for low resolution micro-CT scans that utilizes depth maps to detect fissures on the surface of the lung volume. The fissure's surface location is in turn used to interpolate the fissure throughout the lung volume. Results indicate that the segmentation method results in left and right lung regions consistent with rat lung anatomy.

  11. 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.

  12. Artifacts and pitfalls of high-resolution CT scans.

    Science.gov (United States)

    Hahn, F J; Chu, W K; Anderson, J C; Dobry, C A

    1985-01-01

    Artifacts on CT images have been observed since the introduction of CT scanners. Some artifacts have been corrected with the improvement of technology and better understanding of the image formation and reconstruction algorithms. Some artifacts, however, are still observable in state-of-the-art high-resolution scans. Many investigations on CT artifacts have been reported. Some artifacts are obvious and some are similar to patterns commonly associated with pathological conditions. The present report summarizes some of the causes of artifacts and presents some artifacts that mimic pathology on clinical scans of the head and spine. It is the intention of this report to bring these artifacts and potential pitfalls to the attention of the radiologists so that misinterpretation can be avoided.

  13. 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.)

  14. An automatic approach for 3D registration of CT scans

    Science.gov (United States)

    Hu, Yang; Saber, Eli; Dianat, Sohail; Vantaram, Sreenath Rao; Abhyankar, Vishwas

    2012-03-01

    CT (Computed tomography) is a widely employed imaging modality in the medical field. Normally, a volume of CT scans is prescribed by a doctor when a specific region of the body (typically neck to groin) is suspected of being abnormal. The doctors are required to make professional diagnoses based upon the obtained datasets. In this paper, we propose an automatic registration algorithm that helps healthcare personnel to automatically align corresponding scans from 'Study' to 'Atlas'. The proposed algorithm is capable of aligning both 'Atlas' and 'Study' into the same resolution through 3D interpolation. After retrieving the scanned slice volume in the 'Study' and the corresponding volume in the original 'Atlas' dataset, a 3D cross correlation method is used to identify and register various body parts.

  15. Three-Dimensions Segmentation of Pulmonary Vascular Trees for Low Dose CT Scans

    Science.gov (United States)

    Lai, Jun; Huang, Ying; Wang, Ying; Wang, Jun

    2016-12-01

    Due to the low contrast and the partial volume effects, providing an accurate and in vivo analysis for pulmonary vascular trees from low dose CT scans is a challenging task. This paper proposes an automatic integration segmentation approach for the vascular trees in low dose CT scans. It consists of the following steps: firstly, lung volumes are acquired by the knowledge based method from the CT scans, and then the data are smoothed by the 3D Gaussian filter; secondly, two or three seeds are gotten by the adaptive 2D segmentation and the maximum area selecting from different position scans; thirdly, each seed as the start voxel is inputted for a quick multi-seeds 3D region growing to get vascular trees; finally, the trees are refined by the smooth filter. Through skeleton analyzing for the vascular trees, the results show that the proposed method can provide much better and lower level vascular branches.

  16. 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).

  17. 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).

  18. Role of high resolution multislice CT scan in otosclerosis

    Directory of Open Access Journals (Sweden)

    Atef EL Maraghy

    2015-11-01

    Full Text Available This prospective study was carried out to assess the radiological findings in patients with otosclerosis using high resolution multislice CT scan and to correlate these findings with audiological findings in those patients. This study was done at Al Azhar University hospitals during the period from Jan 2012 to Jun 2014. Thirty-two patients were enrolled in this study; 13 (40.63% males and 19 (59.37% females. Their age ranged from 13 to 55 with a mean of 36.21 ± 8.7 years. Written consent was taken from all patients. Multislice CT scan was done to all patients and reports were done by computer assisted analysis with thorough audiological assessment including pure tone audiometry, tympanometry and stapedial reflex. Positive findings were present in 40/58 ears (69% while negative findings were present in 18/58 ears (31%. Otosclerotic foci were more detected when slice thickness was lesser than one millimeter especially at fissula ante fenestrum and round window region. There was a good correlation between air bone gap and CT score (p = 0.002. High resolution multislice CT helps in the diagnosis of otosclerosis with sensitivity (69% and it aids in the diagnosis of doubtful cases. Otosclerosis has a special predilection to affect certain sites mainly the fissula ante fenestrum followed by the round window and the cochlear promontory.

  19. Combination of CT scanning and fluoroscopy imaging on a flat-panel CT scanner

    Science.gov (United States)

    Grasruck, M.; Gupta, R.; Reichardt, B.; Suess, Ch.; Schmidt, B.; Stierstorfer, K.; Popescu, S.; Brady, T.; Flohr, T.

    2006-03-01

    We developed and evaluated a prototype flat-panel detector based Volume CT (fpVCT) scanner. The fpVCT scanner consists of a Varian 4030CB a-Si flat-panel detector mounted in a multi slice CT-gantry (Siemens Medical Solutions). It provides a 25 cm field of view with 18 cm z-coverage at the isocenter. In addition to the standard tomographic scanning, fpVCT allows two new scan modes: (1) fluoroscopic imaging from any arbitrary rotation angle, and (2) continuous, time-resolved tomographic scanning of a dynamically changing viewing volume. Fluoroscopic imaging is feasible by modifying the standard CT gantry so that the imaging chain can be oriented along any user-selected rotation angle. Scanning with a stationary gantry, after it has been oriented, is equivalent to a conventional fluoroscopic examination. This scan mode enables combined use of high-resolution tomography and real-time fluoroscopy with a clinically usable field of view in the z direction. The second scan mode allows continuous observation of a timeevolving process such as perfusion. The gantry can be continuously rotated for up to 80 sec, with the rotation time ranging from 3 to 20 sec, to gather projection images of a dynamic process. The projection data, that provides a temporal log of the viewing volume, is then converted into multiple image stacks that capture the temporal evolution of a dynamic process. Studies using phantoms, ex vivo specimens, and live animals have confirmed that these new scanning modes are clinically usable and offer a unique view of the anatomy and physiology that heretofore has not been feasible using static CT scanning. At the current level of image quality and temporal resolution, several clinical applications such a dynamic angiography, tumor enhancement pattern and vascularity studies, organ perfusion, and interventional applications are in reach.

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

    Science.gov (United States)

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

    2016-03-01

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

  1. 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)

  2. Diagnosis of pituitary microadenomas by CT scan. Detection of the microadenoma by high resolution coronal scan

    Energy Technology Data Exchange (ETDEWEB)

    Sakoda, K.; Uozumi, T. (Hiroshima Univ. (Japan). School of Medicine)

    1981-10-01

    Following a detection of abnormality of pituitary hormone, it is very important to know whether the abnormality is due to pituitary microadenoma for deciding treatment methods. To diagnose pituitary microadenoma, polytomography of the sella turcica has been used. The recently developed high resolution coronal CT scan is prone to be more valuable in diagnosing microadenoma. New findings by this method were reported.

  3. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-06-19

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

  5. Congenital Pyloric Atresia with Distal Duodenal Atresia- Role of CT Scan

    Directory of Open Access Journals (Sweden)

    Yogender Singh Kadian

    2014-07-01

    Full Text Available The mainstay of diagnosis of congenital pyloric atresia is by plain X-ray of the abdomen showing a large gas bubble with no gas distally. But very rarely it can be associated with distal duodenal atresia when the baby may present as lump abdomen. In such a situation apart from the X-ray, another radiological investigation is needed to delineate the exact nature of the lump. Since the role of ultrasonography is limited in intestinal pathologies and contrast studies are not informative in atresias, the CT scan is the ideal choice. We had managed a case of pyloric atresia with similar presentation with preoperative CT scan.

  6. Spinal uptake mimicking metastasis in SPECT/CT bone scan in a patient with superior vena cava obstruction.

    Science.gov (United States)

    Rager, Olivier; Nkoulou, René; Garibotto, Valentina; Boudabbous, Sana; Arditi, Daniel

    2013-11-01

    A 46-year-old female patient with a mediastinal neuroendocrine carcinoma complicated by superior vena cava syndrome was referred for a bone metastatic workup. Bone scan with SPECT/CT showed several vertebral fixations without alterations on the unenhanced CT, but a CT scan with injection of contrast media showed vertebral densities matched to the lesions described on the SPECT/CT. This pattern confirmed presence of collateral paths through vertebral veins due to superior vena cava syndrome. Lack of metastases was confirmed by MRI.

  7. Dissecting aneurysm of the cervical internal carotid artery. Cervical CT scan findings and treatment - case report

    Energy Technology Data Exchange (ETDEWEB)

    Itoh, Yoshihiro; Itoyama, Youichi; Fukumura, Akinobu; Matsukado, Yasuhiko; Kodama, Takafumi

    1987-06-01

    On lifting a heavy case, a 51-year-old male experienced a sudden onset of headache with giddiness and clouded vision. A week later, vertigo and right hand numbness were added to his symptoms. The next day anisocoria (right > left) and dilation of the left retinal veins were noted. Cranial computed tomography (CT) scan appeared normal and there were no other remarkable neurological findings. The patient was treated conservatively for cerebral infarction, however, the headache worsened and diplopia occurred. Neurological examination on admission revealed nothing unusual except for left Horner's syndrome. Physical examination showed a palpable sausage-like painless tumor on the left side of the neck. Angiography showed a narrowing of the internal carotid artery in the cervical region with a small dissecting aneurysm at the C3 level. Cervical CT scan at the upper C3 level showed a low density lunar defect in the high density section of the enlarged left internal carotid artery. The patient was operated on by superficial temporal artery-middle cerebral artery anastomosis to increase the intracranial blood flow. Postoperatively the symptoms were quickly relieved. Angiography 1 month later showed less narrowing of the carotid artery, though the dissecting aneurysm still remained. Postoperative cervical CT scan showed the left internal carotid artery to be of normal size. The patient returned to his work in normal condition 2 months later. It is emphasized that cervical CT scan may be useful in the diagnosis of this unusual type of cervical dissecting aneurysm.

  8. "Bottle Brush Sign"-Spinal Meningeal Disease on 18F-FDG PET-CT Scan.

    Science.gov (United States)

    Riaz, Saima; Naz, Fozia; Bashir, Humayun; Niazi, Imran Khalid

    2016-09-01

    A 30-year-old man with a history of stage IV AE diffuse large cell lymphoma of left proximal humerus presented with new onset lower limb weakness at completion of chemotherapy. The F-FDG PET-CT scan showed increased intraspinal uptake from T12 to S1 vertebrae with unique "bottle brush" appearance in keeping with spinal meningeal disease. The leptomeningeal disease was further confirmed on correlative MRI scan.

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

    Science.gov (United States)

    Villa, Chiara; Primeau, Charlotte; Hesse, Ulrik; Hougen, Hans Petter; Lynnerup, Niels; Hesse, Birger

    2017-03-01

    Calculation of the estimated body surface area (BSA) by body height and weight has been a challenge in the past centuries due to lack of a well-documented gold standard. More recently, available techniques such as 3D laser surface scanning and CT scanning may be expected to quantify the BSA in an easier and more accurate way. This study provides the first comparison between BSA obtained from post-mortem whole-body CT scans and BSA calculated by nine predictive formulae. The sample consisted of 54 male cadavers ranging from 20 to 87 years old. 3D reconstructions were generated from CT scans using 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 <1·0 using all predictive equations, with the CT scan determination as gold standard. It is concluded that DuBois and DuBois' equation can be safely used in normal-weight male subjects with high accuracy, but it seems likely that BSA is underestimated in underweight subjects and overestimated in overweight individuals. Creation of new formulae specific for overweight subjects and children may be needed.

  10. 3D quantification of soil structure and functioning based on PET and CT scanning techniques

    DEFF Research Database (Denmark)

    Garbout, Amin

    . 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...

  11. 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.

  12. 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.).

  13. Noncontrast perfusion single-photon emission CT/CT scanning: a new test for the expedited, high-accuracy diagnosis of acute pulmonary embolism.

    Science.gov (United States)

    Lu, Yang; Lorenzoni, Alice; Fox, Josef J; Rademaker, Jürgen; Vander Els, Nicholas; Grewal, Ravinder K; Strauss, H William; Schöder, Heiko

    2014-05-01

    Standard ventilation and perfusion (V˙/Q˙) scintigraphy uses planar images for the diagnosis of pulmonary embolism (PE). To evaluate whether tomographic imaging improves the diagnostic accuracy of the procedure, we compared noncontrast perfusion single-photon emission CT (Q˙-SPECT)/CT scans with planar V˙/Q˙scans in patients at high risk for PE. Between 2006 and 2010, most patients referred for diagnosis of PE underwent both Q˙-SPECT/CT scan and planar V˙/Q˙scintigraphy. All scans were reviewed retrospectively by four observers; planar scans were read with modified Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II and Prospective Investigative Study of Pulmonary Embolism Diagnosis (PISA-PED) criteria. On Q˙-SPECT/CT scan, any wedge-shaped peripheral perfusion defect occupying > 50% of a segment without corresponding pulmonary parenchymal or pleural disease was considered to show PE. The final diagnosis was established with a composite reference standard that included ECG, ultrasound of lower-extremity veins, D-dimer levels, CT pulmonary angiography (when available), and clinical follow-up for at least 3 months. One hundred six patients with cancer and mean Wells score of 4.4 had sufficient follow-up; 22 patients were given a final diagnosis of PE, and 84 patients were given a final diagnosis of no PE. According to PIOPED II, 13 studies were graded as intermediate probability. Sensitivity and specificity for PE were 50% and 98%, respectively, based on PIOPED II criteria; 86% and 93%, respectively, based on PISA-PED criteria; and 91% and 94%, respectively, based on Q˙-SPECT/CT scan. Seventy-six patients had additional relevant findings on the CT image of the Q˙-SPECT/CT scan. Noncontrast Q˙-SPECT/CT imaging has a higher accuracy than planar V˙/Q˙imaging based on PIOPED II criteria in patients with cancer and a high risk for PE.

  14. 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)

  15. Case report of subcapsular hemorrhage of the liver in the newborn. Diagnosed and observed by CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Masao; Matsumura, Takafumi; Esumi, Noriko; Tsunamoto, Kentaro; Iino, Shigeru (Kyoto Prefectural Univ. of Medicine (Japan))

    1982-11-01

    A recent case of subcapsular hemorrhage of the liver in a newborn showed that abdominal CT scan was highly useful in the diagnosis of this disease and the follow-up of the healing mechanism of the intrahepatic hemorrhagic lesion.

  16. 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

  17. 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.

  18. CT SCAN: THE TOUR GUIDE FOR THE MANAGEMENT OF THE EDH

    Directory of Open Access Journals (Sweden)

    Somashekhar

    2015-02-01

    Full Text Available EDH is considered as common and one of the important preventable complications in head injury. This condition may require aggressive management depending on the various clinical and radiological factors on continuous assessment of the patients. This study was carried out to evaluate the presentation of patients with extradural haematoma secondary to head injury an d to assess the factors influencing the mode of management and also the outcome. 50 patients with cranial extradural haematoma were admitted in the neurosurgical department during the period of 2 years. All the patients with head injury on CT scan diagnose d to have EDH were included in the study. The management includes conservative measures and/or decompressive craniotomy. Temporo - parietal (20% and temporal region(20% was the most common location of EDH. The most significant factors which influences surg ical mode of management were higher age group, lower GCS and the CT scan variables showing greater clot volume and thickness. Increased interval between the times of trauma to surgery and lower GCS was very significantly associated with unfavourable outcom e along with CT scan variables irrespective of mode of management. From this study we concluded that neurological status of the patients on presentation and the volumetric details of EDH are the most important factors in management and outcome of EDH. With early detection and treatment due to better connectivity of the patients to hospitals, with the help of CT scan and good hospital care, we can expect a decrease in the number of unfavorable outcomes.

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

    Science.gov (United States)

    Bohl, Michael; Francois, Webster; Gest, Thomas

    2011-07-01

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

  20. Quality assurance of CT scanning for industrial applications

    DEFF Research Database (Denmark)

    Angel, Jais Andreas Breusch

    ClassWeb through volume comparisons to real dissections of pig carcasses. For the real dissections, volumes of tissue types such as bone, lean meat and fat, are estimated using commercial VolumeGraphics software. It is detected that the ANOVA and the residuals from the virtual dissection fail the normality test...... to 158 μm, compared to average uncertainties below 5.5 μm using CMMs. A test was performed to check if X-ray contrast modalities can be applied for metrological purposes. Traditionally, segmentation between multi-materials in CT scanning is done by using different edge detection techniques and threshold...... to 1348 mL, compared to average uncertainties below 10 mL using the gravimetric method. DMRI and DTU Compute have previously developed advanced image analysis software (PigClassWeb) which performs virtual dissections in pig carcasses. A DOE was carried out to document the performance of Pig...

  1. Intrapartum FHR monitoring and neonatal CT brain scan

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Yoshiki; Ukita, Masahiko; Nakada, Eizo (Kurashiki Central Hospital, Okayama (Japan))

    1982-12-01

    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.

  2. 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)

  3. CT evaluation of solitary pulmonary nodule : value of additional HRCT scan

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jeung Sook; Kwak Jin Young; Lee, Seung Ik; Ha, Doo Hoe [Pundang CHA General Hospital, Pochon CHA Univ. College of Medicine, Sungnam (Korea, Republic of); Kim, Tae Sung; Hwang, Jung Hwa; Lee, Kyung Soo [Samsung Medical Center, Sungkyunkwan Univ. College of Medicine, Seoul (Korea, Republic of); Kim, Yook Yung [Ewha Womans Univ. College of Medicine, Seoul (Korea, Republic of)

    1999-04-01

    The aim of our study was to evaluate the usefulness of high-resolution CT scans in addition to helical CT for characterizing a solitary pulmonary nodule. Our study included 49 patients with a solitary pulmonary nodule ; in each patient this was evaluated by both additional high-resolution CT and helical scanning. Images were evaluated by three independent observers, each of whom read them twice : initially with helical CT images only and then with helical images plus high-resolution CT images. After analysis, the observers recorded the following : histologic diagnosis, benignancy or malignancy of a nodule, and confidence in their diagnosis (three scales). In differentiating benign and malignant nodules, the accuracy of helical scans only was 75% (110/147 readings) whereas that of helical plus high-resolution CT scans was 82% (121/147 readings)({rho}=0.001). Correct histologic diagnosis was made in 47% of cases (69/147 readings) when helical scans only had been evaluated and in 48% of cases (71/147 readings) for which both helical and high-resolotion CT scans were available ({rho}=0.815). Diagnosis was more often highly confident on the basis of additional high-resolution CT scans (25%) than helical scans only (5%) ({rho}=0.001). By enhancing differential diagnostic accuracy between benign and malignant nodules and by increasing confidence in the histologic diagnosis of a pulmonary nodule, additional high-resolution CT scans are valuable for the evaluation of a solitary pulmonary nodule.

  4. Cardiac CT angiography after coronary artery surgery in children using 64-slice CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Marini, Davide; Agnoletti, Gabriella [Centre de Reference Malformations Cardiaques Congenitales Complexes-M3C, Universite Paris Descartes, UFR Necker-Enfants Malades, Paris (France); Brunelle, Francis [University Paris Descartes, UFR Necker-Enfants Malades, Department of Pediatric Radiology, APHP, Paris (France); Sidi, Daniel; Bonnet, Damien [Centre de Reference Malformations Cardiaques Congenitales Complexes-M3C, Universite Paris Descartes, UFR Necker-Enfants Malades, Paris (France); Ou, Phalla [Centre de Reference Malformations Cardiaques Congenitales Complexes-M3C, Universite Paris Descartes, UFR Necker-Enfants Malades, Paris (France); University Paris Descartes, UFR Necker-Enfants Malades, Department of Pediatric Radiology, APHP, Paris (France)], E-mail: phalla.ou@nck.aphp.fr

    2009-09-15

    Objective: The purpose of this study was to compare the diagnostic accuracy of 64-slice CT with that of invasive angiography in the detection of graft and/or coronary angioplasty stenosis in children who had undergone coronary artery surgery. Population and methods: Fifteen consecutive children (8 male and 7 female; age 9.2 {+-} 6.1 years) underwent 64-slice CT because of chest pain or ECG changes mean 4.8 {+-} 3.7 years after surgical coronary artery surgery; 10 patients had coronary angioplasty using a patch from the saphenous vein, four had mammary artery bypass, and one had saphenous vein bypass. Six main segments of the coronary arteries and all the bypass graft considered as a single segment were analyzed and compared with invasive angiography used as the reference standard. Results: CT correctly identified the four children with coronary angioplasty and mammary graft lesions that were confirmed by conventional angiography: one patient had a significant stenosis (>50% stenosis) at the mammary bypass graft anastomosis site; three other had non-significant stenosis (<50% stenosis) including a mild lesion of the saphenous vein patch in two patients and a mild lesion at the anastomosis site of the mammary bypass in one. All segments identified as normal by CT in the other 11 children were also found to be normal by conventional angiography. Conclusion: In centers expert in this technique, 64-slice CT scanning is a promising, rapid, and useful diagnostic technique for evaluating both coronary angioplasty and bypass graft lesions in children who had undergone coronary artery surge0008.

  5. Using the fourth dimension to distinguish between structures for anisotropic diffusion filtering in 4D CT perfusion scans

    NARCIS (Netherlands)

    Mendrik, AM; Vonken, EPA; Witkamp, TD; Prokop, Mathias; Van Ginneken, Bram; Viergever, Max A.

    2015-01-01

    High resolution 4D (3D+time) cerebral CT perfusion (CTP) scans can be used to create 3D arteriograms (showing only arteries) and venograms (only veins). However, due to the low X-ray radiation dose used for acquiring the CTP scans, they are inherently noisy. In this paper, we propose a time intensit

  6. Combined 18F-Fluoride and 18F-FDG PET/CT Scanning for Evaluation of Malignancy: Results of an International Multicenter Trial

    DEFF Research Database (Denmark)

    Iagaru, Andrei; Mittra, Erik; Mosci, Camila;

    2012-01-01

    -FDG PET/CT. The 3 PET/CT scans were performed sequentially within 4 wk of one another for each patient. Results: 18F2/18FFDG PET/CT allowed for accurate interpretation of radiotracer uptake outside the skeleton, with findings similar to those of 18F-FDG PET/CT. In 19 participants, skeletal disease...... was more extensive on 18F2 PET/CT and 18F2/18F-FDG PET/CT than on 18F-FDG PET/CT. In another 29 participants, 18F2 PET/CT and 18F2/18F-FDG PET/CT showed osseous metastases where 18FFDG PET/CT was negative. The extent of skeletal lesions was similar in 18 participants on all 3 scans. Conclusion: This trial...

  7. 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)

  8. Combining generative and discriminative models for semantic segmentation of CT scans via active learning.

    Science.gov (United States)

    Iglesias, Juan Eugenio; Konukoglu, Ender; Montillo, Albert; Tu, Zhuowen; Criminisi, Antonio

    2011-01-01

    This paper presents a new supervised learning framework for the efficient recognition and segmentation of anatomical structures in 3D computed tomography (CT), with as little training data as possible. Training supervised classifiers to recognize organs within CT scans requires a large number of manually delineated exemplar 3D images, which are very expensive to obtain. In this study, we borrow ideas from the field of active learning to optimally select a minimum subset of such images that yields accurate anatomy segmentation. The main contribution of this work is in designing a combined generative-discriminative model which: i) drives optimal selection of training data; and ii) increases segmentation accuracy. The optimal training set is constructed by finding unlabeled scans which maximize the disagreement between our two complementary probabilistic models, as measured by a modified version of the Jensen-Shannon divergence. Our algorithm is assessed on a database of 196 labeled clinical CT scans with high variability in resolution, anatomy, pathologies, etc. Quantitative evaluation shows that, compared with randomly selecting the scans to annotate, our method decreases the number of training images by up to 45%. Moreover, our generative model of body shape substantially increases segmentation accuracy when compared to either using the discriminative model alone or a generic smoothness prior (e.g. via a Markov Random Field).

  9. 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.

  10. 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.

  11. CT scan in diagnosis of pituitary adenomas, 5. CT findings of GH secreting adenomas

    Energy Technology Data Exchange (ETDEWEB)

    Sakoda, K.; Yonezawa, M.; Gen, M. (Hiroshima Univ. (Japan). School of Medicine)

    1981-10-01

    Clinical findings and radiological findings in 19 cases of GH secreting adenoma were reported. In diagnosis of GH secreting adenoma, conventional radiography and computed tomography of the sella turcica are useful. The CT of this kind of adenomas shows a characteristically higher x-ray absorption coefficient than other adenomas.

  12. Development of 1-year-old computational phantom and calculation of organ doses during CT scans using Monte Carlo simulation.

    Science.gov (United States)

    Pan, Yuxi; Qiu, Rui; Gao, Linfeng; Ge, Chaoyong; Zheng, Junzheng; Xie, Wenzhang; Li, Junli

    2014-09-21

    With the rapidly growing number of CT examinations, the consequential radiation risk has aroused more and more attention. The average dose in each organ during CT scans can only be obtained by using Monte Carlo simulation with computational phantoms. Since children tend to have higher radiation sensitivity than adults, the radiation dose of pediatric CT examinations requires special attention and needs to be assessed accurately. So far, studies on organ doses from CT exposures for pediatric patients are still limited. In this work, a 1-year-old computational phantom was constructed. The body contour was obtained from the CT images of a 1-year-old physical phantom and the internal organs were deformed from an existing Chinese reference adult phantom. To ensure the organ locations in the 1-year-old computational phantom were consistent with those of the physical phantom, the organ locations in 1-year-old computational phantom were manually adjusted one by one, and the organ masses were adjusted to the corresponding Chinese reference values. Moreover, a CT scanner model was developed using the Monte Carlo technique and the 1-year-old computational phantom was applied to estimate organ doses derived from simulated CT exposures. As a result, a database including doses to 36 organs and tissues from 47 single axial scans was built. It has been verified by calculation that doses of axial scans are close to those of helical scans; therefore, this database could be applied to helical scans as well. Organ doses were calculated using the database and compared with those obtained from the measurements made in the physical phantom for helical scans. The differences between simulation and measurement were less than 25% for all organs. The result shows that the 1-year-old phantom developed in this work can be used to calculate organ doses in CT exposures, and the dose database provides a method for the estimation of 1-year-old patient doses in a variety of CT examinations.

  13. 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...

  14. A computational framework for cancer response assessment based on oncological PET-CT scans.

    Science.gov (United States)

    Sampedro, Frederic; Escalera, Sergio; Domenech, Anna; Carrio, Ignasi

    2014-12-01

    In this work we present a comprehensive computational framework to help in the clinical assessment of cancer response from a pair of time consecutive oncological PET-CT scans. In this scenario, the design and implementation of a supervised machine learning system to predict and quantify cancer progression or response conditions by introducing a novel feature set that models the underlying clinical context is described. Performance results in 100 clinical cases (corresponding to 200 whole body PET-CT scans) in comparing expert-based visual analysis and classifier decision making show up to 70% accuracy within a completely automatic pipeline and 90% accuracy when providing the system with expert-guided PET tumor segmentation masks. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Improving CT scan capabilities with a new trauma workflow concept: Simulation of hospital logistics using different CT scanner scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Fung Kon Jin, P.H.P., E-mail: p.fungkonjin@amc.uva.nl [Trauma Unit Department of Surgery, Academic Medical Center, Amsterdam (Netherlands); Dijkgraaf, M.G.W., E-mail: m.dijkgraaf@amc.uva.nl [Department of Clinical Epidemiology, Biostatistics, and Bioinformatics, Academic Medical Center, Amsterdam (Netherlands); Alons, C.L., E-mail: clalons@few.vu.nl [Department of Mathematics, VU University Amsterdam, Amsterdam (Netherlands); Kuijk, C. van, E-mail: c.vankuijk@vumc.nl [Department of Radiology, VU Medical Center, Amsterdam (Netherlands); Beenen, L.F.M., E-mail: l.beenen@amc.uva.nl [Department of Radiology, Academic Medical Center, Amsterdam (Netherlands); Koole, G.M., E-mail: koole@few.vu.nl [Department of Mathematics, VU University Amsterdam, Amsterdam (Netherlands); Goslings, J.C., E-mail: j.c.goslings@amc.uva.nl [Trauma Unit Department of Surgery, Academic Medical Center, Amsterdam (Netherlands)

    2011-11-15

    Introduction: The Amsterdam Trauma Workflow (ATW) concept includes a sliding gantry CT scanner serving two mirrored (trauma) rooms. In this study, several predefined scenarios with a varying number of CT scanners and CT locations are analyzed to identify the best performing patient flow management strategy from an institutional perspective on process quality. Materials and methods: A total of six clinically relevant scenarios with variables that included the number of CT scanners, CT scanner location, and different patient categories (regular, urgent, and trauma patients) were evaluated using computer simulation. Each scenario was simulated using institutional data and was assessed for patient waiting times, idle time of CT scanners, and overtime due to scheduling. The best 2- and 3-scanner scenarios were additionally evaluated with the ATW-concept. Results: Based on institutional data, the best 2-scanner scenario distributes all 3 patient categories over both scanners and plans 4 urgent patients per hour while locating both scanners outside of the trauma room. The best 3-scanner scenario distributes urgent and regular patients over all 3 scanners and trauma patients on only 1 scanner and locates all CT scanners outside of the trauma room. The ATW concept reduces waiting times and overtime, while increasing idle time. Conclusion: Choosing the optimal planning and distribution strategies depends on the number and location of available CT scanners, along with number of trauma, urgent and regular patients. The Amsterdam Trauma Workflow concept could provide institutions with the ability of early CT scanning in trauma patients without influencing regular and urgent CT scanning.

  16. Total-body CT scanning in trauma patients: Benefits and boundaries

    NARCIS (Netherlands)

    Sierink, J.C.

    2015-01-01

    Computed tomography (CT) scanning has become essential in the early diagnostic phase of trauma care. It is a fast and highly accurate modality for the identification of various injuries and it enables a rapid response to life-threatening problems. Especially total-body CT (TBCT) scanning is increasi

  17. 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.

  18. Low-dose computed tomography scans with automatic exposure control for patients of different ages undergoing cardiac PET/CT and SPECT/CT.

    Science.gov (United States)

    Yang, Ching-Ching; Yang, Bang-Hung; Tu, Chun-Yuan; Wu, Tung-Hsin; Liu, Shu-Hsin

    2017-06-01

    This study aimed to evaluate the efficacy of automatic exposure control (AEC) in order to optimize low-dose computed tomography (CT) protocols for patients of different ages undergoing cardiac PET/CT and single-photon emission computed tomography/computed tomography (SPECT/CT). One PET/CT and one SPECT/CT were used to acquire CT images for four anthropomorphic phantoms representative of 1-year-old, 5-year-old and 10-year-old children and an adult. For the hybrid systems investigated in this study, the radiation dose and image quality of cardiac CT scans performed with AEC activated depend mainly on the selection of a predefined image quality index. Multiple linear regression methods were used to analyse image data from anthropomorphic phantom studies to investigate the effects of body size and predefined image quality index on CT radiation dose in cardiac PET/CT and SPECT/CT scans. The regression relationships have a coefficient of determination larger than 0.9, indicating a good fit to the data. According to the regression models, low-dose protocols using the AEC technique were optimized for patients of different ages. In comparison with the standard protocol with AEC activated for adult cardiac examinations used in our clinical routine practice, the optimized paediatric protocols in PET/CT allow 32.2, 63.7 and 79.2% CT dose reductions for anthropomorphic phantoms simulating 10-year-old, 5-year-old and 1-year-old children, respectively. The corresponding results for cardiac SPECT/CT are 8.4, 51.5 and 72.7%. AEC is a practical way to reduce CT radiation dose in cardiac PET/CT and SPECT/CT, but the AEC settings should be determined properly for optimal effect. Our results show that AEC does not eliminate the need for paediatric protocols and CT examinations using the AEC technique should be optimized for paediatric patients to reduce the radiation dose as low as reasonably achievable.

  19. 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....../CT scanning for newly diagnosed cervical cancer FIGO stage >or=1B has a high sensitivity and specificity, and can be a valuable supplement to the FIGO staging procedure....

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

    Science.gov (United States)

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

    2017-05-01

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

  1. 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.

  2. 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.

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

    DEFF Research Database (Denmark)

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

    2016-01-01

    manually contoured eight anatomical regions-of-interest (ROI) twice on pCT and once on rCT. METHODS: 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...... 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 elastix in HNSCC on planning and recurrence CT scans is feasible...

  4. 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.

  5. The value of baseline CT head scans in the assessment of shunt complications in hydrocephalus

    Energy Technology Data Exchange (ETDEWEB)

    Cantrell, P. (Alder Hey Children' s Hospital, Liverpool (United Kingdom)); Fraser, F. (Alder Hey Children' s Hospital, Liverpool (United Kingdom)); Pilling, D. (Alder Hey Children' s Hospital, Liverpool (United Kingdom)); Carty, H. (Alder Hey Children' s Hospital, Liverpool (United Kingdom))

    1993-10-01

    The purpose of this study was to determine the value of a baseline CT head scan in the assessment of patients who subsequently presented with symptoms which may have been due to shunt complications (such as blockage or infection). In all these patients the shunt had been inserted in the treatment of hydrocephalus. We conclude that the presence of a baseline scan does not add to the interpretation of CT scans done when the patient presents with symptoms of possible shunt malfunction. (orig.)

  6. 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.

  7. Course and variation of the intercostal artery by CT scan.

    Science.gov (United States)

    Helm, Emma J; Rahman, Najib M; Talakoub, Omid; Fox, Danial L; Gleeson, Fergus V

    2013-03-01

    It is conventionally taught that the intercostal artery is shielded in the intercostal groove of the superior rib. The continuous course and variability of the intercostal artery, and factors that may influence them, have not been described in a large number of arteries in vivo. Maximal intensity projection reformats in the coronal plane were produced from CT scan pulmonary angiograms to identify the posterolateral course of the intercostal artery (seventh to 11th rib spaces). A novel semiautomated computer segmentation algorithm was used to measure distances between the lower border of the superior rib, the upper border of the inferior rib, and the position of the intercostal artery when exposed in the intercostal space. The position and variability of the artery were analyzed for association with clinical factors. Two hundred ninety-eight arteries from 47 patients were analyzed. The mean lateral distance from the spine over which the artery was exposed within the intercostal space was 39 mm, with wide variability (SD, 10 mm; 10th-90th centile, 28-51 mm). At 3 cm lateral distance from the spine, 17% of arteries were shielded by the superior rib, compared with 97% at 6 cm. Exposed artery length was not associated with age, sex, rib space, or side. The variability of arterial position was significantly associated with age (coefficient, 0.91; P intercostal artery is exposed within the intercostal space in the first 6 cm lateral to the spine. The variability of its vertical position is greater in older patients and in more cephalad rib spaces.

  8. [Exposure to CT scans in childhood and long-term cancer risk: A review of epidemiological studies].

    Science.gov (United States)

    Baysson, Hélène; Journy, Neige; Roué, Tristan; Ducou-Lepointe, Hubert; Etard, Cécile; Bernier, Marie-Odile

    2016-02-01

    Amongst medical exams requiring ionizing radiation, computed tomography (CT) scans are used more frequently, including in children. These CT examinations are associated with absorbed doses that are much higher than those associated with conventional radiology. In comparison to adults, children have a greater sensitivity to radiation and a longer life span with more years at cancer risks. Five epidemiological studies on cancer risks after CT scan exposure during childhood were published between 2012 and 2015. The results of these studies are consistent and show an increase of cancer risks in children who have been exposed to several CT scans. However, methodological limits due to indication bias, retrospective assessment of radiation exposure from CT scans and lack of statistical power are to be taken into consideration. International projects such as EPI-CT (Epidemiological study to quantify risks for pediatric computerized tomography and to optimize dose), with a focus on dosimetric reconstruction and minimization of bias will provide more precise results. In the meantime, available results reinforce the necessity of justification and optimization of doses.

  9. Acute pyelonephritis: role of enhanced CT scan in the prediction of clinical outcome

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Byung June; Kim, Ki Whang; Yu, Jeong Sik; Kim, Jai Keun; Yoon, Sang Wook; Ha, Sung Kyu; Park, Chong Hoon [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    1997-04-01

    To correlate the CT findings of acute pyelonephritis with its outcome and with clinical data. Thirty five contrast enhanced CT scans in patients diagnosed as suffering from acute pyelonephritis were retrospectively analyzed. Findings based on the morphology of perfusion defect in the renal parenchyma were classified as normal, focal wedge, multifocal wedge, focal mass, or mixed form composed of wedge and mass. These findings were correlated with clinical data such as degree of fever, leukocytosis, the period after antibiotic treatment during which fever was reduced, and the presence of pyuria in each group Analysis was then performed. Perfusion defects were seen in 23 of 35 cases, and their morphology was classified as follow; focal wedge (n=2), multifocal wedge (n=8), focal mass (n=4), and mixed form (n=9). Twelve cases (34.3%) showed no perfusion defect. The duration of fever was significantly prolonged in patients with focal mass form (p < .05). There was no significant correlation between the morphology of perfusion defect, bilaterality, and other clinical factors. The present study shows that the clinical course of the focal mass form of perfusion defect, as seen on CT, is different from that of other types. CT could be effective in predicting clinical progress and the outcome of treatment in cases of acute pyelonephritis.

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

    Science.gov (United States)

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

    2014-11-01

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

  11. 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.

  12. Cervical spine evaluation in urban trauma centers: lowering institutional costs and complications through helical CT scan.

    Science.gov (United States)

    Grogan, Eric L; Morris, John A; Dittus, Robert S; Moore, Derek E; Poulose, Benjamin K; Diaz, Jose J; Speroff, Theodore

    2005-02-01

    In the evaluation of the cervical spine (c-spine), helical CT scan has higher sensitivity and specificity than plain radiographs in the moderate- and high-risk trauma population, but is more costly. We hypothesize that institutional costs associated with missed injuries make helical CT scan the least costly approach. A cost-minimization study was performed using decision analysis examining helical CT scan versus radiographic evaluation of the c-spine. Parameter estimates were obtained from the literature for probability of c-spine injury, probability of paralysis after missed injury, plain film sensitivity and specificity, CT scan sensitivity and specificity, and settlement cost of missed injuries resulting in paralysis. Institutional costs of CT scan and plain radiography were used. Sensitivity analyses tested robustness of strategy preference, accounted for parameter variability, and determined threshold values for individual parameters on strategy preference. C-spine evaluation with helical CT scan has an expected cost of US 554 dollars per patient compared with US 2,142 dollars for plain films. CT scan is the least costly alternative if threshold values exceed US 58,180 dollars for institutional settlement costs, 0.9% for probability of c-spine fracture, and 1.7% for probability of paralysis. Plain films are least costly if CT scan costs surpass US 1,918 dollars or plain film sensitivity exceeds 90%. Helical CT scan is the preferred initial screening test for detection of cervical spine fractures among moderate- to high-risk patients seen in urban trauma centers, reducing the incidence of paralysis resulting from false-negative imaging studies and institutional costs, when settlement costs are taken into account.

  13. Vascular anatomy of the liver and porta hepatis with dynamic CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Hiramatsu, Yoshihiro; Wada, Mitsuyoshi; Nakajima, Teiichi; Tonooka, Reiko; Matsumoto, Kunihiko

    1983-01-01

    Vascular anatomy of the liver and porta heaptis demonstrated by dynamic CT scan was studied Identification of the individual vessels was sometimes difficult due to slight differencies in respiratory depths among the scans. Limitation in the number of slices also made the evalution of the vascular anatomy difficult. Angiography was therefore utilized for comparison in identifying the vessels. Dynamic CT scan was proved to be usefull in demonstrating the anteroposterior relationship of the vessels and surrounding structures, which is difficult with convetional angiography without multiple projections. Three dimensional understanding of the vessels was then possible with dynamic CT scan and angiography. When combined with recently advancing digital subtraction angiography, dynamic CT scan might reduce the necessity for conventional angiography with Seldinger's technique. (author).

  14. Is It Possible to Predict Heart Rate and Range during Enhanced Cardiac CT Scan from Previous Non-enhanced Cardiac CT?

    OpenAIRE

    Horiguchi, Jun; Yamamoto, Hideya; Arie, Ryuichi; Kiguchi, Masao; Fujioka, Chikako; Ohtaki, Megu; Kihara, Yasuki; Awai, Kazuo

    2010-01-01

    The effect of heart rate and variation during cardiac computed tomography (CT) on the examination quality. The purpose of this study is to investigate whether it is possible to predict heart rate and range during enhanced cardiac computed CT scan from previous non-enhanced cardiac CT scan. Electrocardiograph (ECG) files from 112 patients on three types of cardiac 64-slice CT (non-enhanced, prospective ECG-triggered and retrospective ECG-gated enhanced scans) were recorded. The mean heart rate...

  15. Brain tumors and CT scan in infants and children, (1). The impact on pediatric neuroradiology

    Energy Technology Data Exchange (ETDEWEB)

    Ohi, S.; Velasco, J.M. (Northwestern Univ., Chicago, IL (USA). Medical School)

    1980-10-01

    The dramatic change in the neuroradiological procedures have been noted after CT scan was introduced in the last several years. Remarkable decreasing numbers of angiographic, pneumoencephalographic and other invasive neuroradiologic studies as well as nuclear brain scan were also found in the pediatric neuroradiology. The authors analyzed the total numbers of these studies performed in the last several years in pediatric neurological/neurosurgical practice in the light of the impact of CT scan especially in the diagnostic procedures and treatments of brain tumor in children. Although the number of these procedures decreased up to 49% in plain skull X-ray, 54% in cerebral angiography, 70% in pneumoencephalography/ventriculography and 79% in nuclear brain scan after CT scan was installed in our results, it is extremely important to renew understanding of those characteristics in each special procedures. Cerebral angiography as well as pneumoencephalography may give the surgeon more precise ideas of the anatomical relationship between the lesion and other normal structures, especially in the posterior fossa tumor in which CT scan occassionally demonstrates only a gross finding. A case with false negative result and another case with a complicated anatomical structure in CT scan were presented. The significance of cerebral angiography and other invasive studies in the diagnosis and follow up of brain tumor in CT scan were discussed.

  16. 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.

  17. Value of CT scan in the diagnosis of primary large bowel lymphoma

    Institute of Scientific and Technical Information of China (English)

    赵修义; 张雪林; 王劲; 郑卫权; 文戈

    2003-01-01

    Objective:To study the CT imaging of primary large bowel lymphoma and evaluate the value of CT scan.Methods:CT reports of 8 patients with proven primary large bowel lymphoma were retrospectively reviewed.Plain CT scans were done on all patients,enhanced CT scans simultaneously with 5 - 10 mm section thickness,and 5 - 10 mm table increments in 6 cases.Results:Primary involved sites were on the cecum(n = 3),the ascending colon(n = 2),and the rectum(n = 1).The tumor was found in multiple areas of the large bowel in 2 cases.CT appearance fell into 3 typical patterns in our study.The first was focal mass type in 2 cases,with one combined with intussusception and retroperitoneal adenopathy; the second was segmental annular involvement type in 3 cases,with one of them combined with mesenteric adenopathy; the last was diffuse involvement type in 2 cases.Multiple nodules were seen in the rectum in 1 case.Conclusion:CT was found to be accurate in detecting the primary sites and complications of lymphoma,and evaluating invasion of adjacent structures; Focal mass type,segmental annular involvement type and diffuse involvement type are the main patterns of CT features in the primary large bowel lymphoma; The features revealed by CT scan are suggestive of primary large bowel lymphoma in some cases.

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

    Directory of Open Access Journals (Sweden)

    A. Liotta

    2014-01-01

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

  19. Giant aneurysm of the distal anterior cerebral artery simulating brain tumor on CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Shigemori, Minoru; Kawaba, Tomoyuki; Kuramoto, Shinken (Kurume Univ., Fukuoka (Japan). School of Medicine); Ogata, Takeyuki; Yoshimura, Kyoko

    1982-08-01

    A successfully treated case with a giant aneurysm of the distal anterior cerebral artery which simulated brain tumor on computerized tomography (CT) is reported. In a 69-year-old woman suffering with a mild headache and a weakness in the left leg, a plain skull film revealed a ballooning of the sella turcica and an erosion of the dorsum. A CT scan showed a round or oval high-density area at the medial site of the right frontal lobe which was associated with an extensive low-density area. Curviliner calcification was also noted. A marked attenuation of the medial site of the mass lesion was demonstrated with contrast enhancement. A left-carotid angiogram demonstrated a large aneurysm at the distal-branching point of the anterior cerebral artery. Radical treatment for the aneurysm was performed. The postoperative course was uneventful, and the low-density area around the aneurysm disappeared within 6 weeks after the operation.

  20. Metastatic Neuroblastoma in Adult Patient, Presenting as a Super Scan on 68Ga-DOTANOC PET/CT Imaging.

    Science.gov (United States)

    Malik, Dharmender; Jois, Abhiram; Singh, Harmandeep; Bora, Girdhar S; Basher, Rajender Kumar; Mittal, Bhagwant Rai

    2017-09-01

    We report a case of 23-year-old man who presented with complaints of progressive abdominal distension for the past 3 months along with the loss of appetite and weight and had a large solid cystic mass in the left half of the abdominal cavity revealed on ultrasonography and contrast-enhanced CT of the abdomen. Subsequent biopsy and histopathology revealed it to be neuroblastoma. Ga-DOTANOC PET/CT scan performed to rule out distant metastasis showed intense radiotracer uptake distributed throughout the skeleton, mimicking a super scan.

  1. 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...

  2. An Effort to Develop an Algorithm to Target Abdominal CT Scans for Patients After Gastric Bypass.

    Science.gov (United States)

    Pernar, Luise I M; Lockridge, Ryan; McCormack, Colleen; Chen, Judy; Shikora, Scott A; Spector, David; Tavakkoli, Ali; Vernon, Ashley H; Robinson, Malcolm K

    2016-10-01

    Abdominal CT (abdCT) scans are frequently ordered for Roux-en-Y gastric bypass (RYGB) patients presenting to the emergency department (ED) with abdominal pain, but often do not reveal intra-abdominal pathology. We aimed to develop an algorithm for rational ordering of abdCTs. We retrospectively reviewed our institution's RYGB patients presenting acutely with abdominal pain, documenting clinical and laboratory data, and scan results. Associations of clinical parameters to abdCT results were examined for outcome predictors. Of 1643 RYGB patients who had surgery between 2005 and 2015, 355 underwent 387 abdCT scans. Based on abdCT, 48 (12 %) patients required surgery and 86 (22 %) another intervention. No clinical or laboratory parameter predicted imaging results. Imaging decisions for RYGB patients do not appear to be amenable to a simple algorithm, and patient work-up should be based on astute clinical judgment.

  3. 18F-FDG PET/CT Scan Can Predate Clinical Presentation in Acute Appendicitis.

    Science.gov (United States)

    Ali, Syed Zama; Yin, Loi Hoi; Kin, Khor Lih; Sinha, Arvind Kumar; Poon, Li Mei

    2017-09-01

    Acute appendicitis is a clinical diagnosis typically presenting with right lower quadrant pain. We describe the case of an asymptomatic 53-year-old man with stage 2A diffuse large B-cell lymphoma, who underwent F-FDG PET/CT at the completion of chemotherapy. The scan showed complete lymphomatous disease remission. Incidentally, there was increased FDG uptake in a tubular structure adjacent to the cecum. Clinical examination was negative. Subsequently, the patient presented 6 days later with typical acute appendicitis symptoms. This case is interesting wherein increased FDG uptake in the appendix predated the appearance of clinical symptoms.

  4. 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.

  5. Comparison of 18F-FDG PET/CT, 99mTc-methy-isobutyl-isonitrile(MIBI) scan and radioiodine diagnostic whole body scan with I-131 post-therapeutic whole body scan in papillary thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chung Ho; Park, Young Ha; Yoo, Ie Ryung; Kim, Sung Hoon; Chung, Soo Kyo [The Catholic University of Korea, Seoul (Korea, Republic of)

    2007-07-01

    To evaluate the usefulness of 18F-FDG PET/CT and 99mTc-MIBI scan in the detection of remnant thyroid tissue, recurrence or metastasis before high dose I-131 ablation therapy. Twenty-four patients (20 female, 4 male, age=52.913.2), who received 99mTc-MIBI scan, radioiodine diagnostic whole body scan (WBS) and 18F-FDG PET/CT within a week before high dose I-131 ablation therapy from May 2004 to September 2007 were retrospectively reviewed. All patients thyroid stimulating hormone, thyroglobulin (Tg) and anti-thyroglobulin level were checked before administering I-123 or I-131 for diagnostic WBS. TSH level were higher than 30 mIU/L in all patients. The radioiodine diagnostic WBS, 99mTc-MIBI scan and 18F-FDG PET/CT were compared with the post-therapeutic WBS obtain 7 days after administration of I-131 (=150 mCi). Post-therapeutic WBS of 4 patients showed distant metastases, commonly in lung, all 4 were positive on 18F-FDG PET/CT, 1 on 99mTc-MIBI scan, but none of them were detectable on radioiodine diagnostic WBS. 7 patients with cervical or supraclavicular lymph node metastases on post-therapeutic WBS, 5 were positive on 18F-FDG PET/CT, 4 on radioiodine diagnostic WBS, and 3 on 99mTc-MIBI scan. 9 patients with remnant thyroid tissue only in thyroid bed, 7 were positive on radioiodine diagnostic WBS, 5 on 18F-FDG PET/CT and 3 on 99mTc-MIBI scan. One case with high Tg level (>10ng/mI) was positive only on post-therapeutic WBS scan. 3 patients with high Tg level, all of diagnostic scans and post-therapeutic scan were negative. Compared to the post-therapeutic WBS with radioiodine diagnostic WBS, 99mTc-MIBI scan, 18F-FDG PET/CT, none of the studies were perfectly matched with post-therapeutic WBS, but can compensate each other. 18F-FDG PET/CT might be helpful, when lymph node or lung metastasis is suspected. Further evaluation with larger population is necessary.

  6. Definitive role of CT scanning of the pancreas. The second year's experience.

    Science.gov (United States)

    Haaga, J R; Alfidi, R J; Havrilla, T R; Tubbs, R; Gonzalez, L; Meaney, T F; Corsi, M A

    1977-09-01

    In a group of 188 patients, 192 computed tomographic (CT) scans of the pancreas were done, and the diagnostic accuracy of CT determined relative to other modalities. CT was the most effective method of detecting neoplastic and inflammatory diseases. The full extent of the disease process, including involvement of the retroperitoneum and metastasis to the liver, was visualized with one examination. Calcification and cystic collections associated with pancreatitis were also clearly seen.

  7. 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...

  8. 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 betwee...

  9. Patient-centered clinical impact of incidentally detected abnormalities on chest CT scans

    Directory of Open Access Journals (Sweden)

    Sherine G. Moftah

    2014-09-01

    Conclusion: The clinically significant different incidental abnormalities on chest CT scans represented 10.4% of all incidental findings, 3.3% were due to malignancies. The clinical impact of incidental abnormalities on chest CT may be of utmost importance on patient care.

  10. 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…

  11. 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…

  12. Increase in dicentric chromosome formation after a single CT scan in adults.

    Science.gov (United States)

    Abe, Yu; Miura, Tomisato; Yoshida, Mitsuaki A; Ujiie, Risa; Kurosu, Yumiko; Kato, Nagisa; Katafuchi, Atsushi; Tsuyama, Naohiro; Ohba, Takashi; Inamasu, Tomoko; Shishido, Fumio; Noji, Hideyoshi; Ogawa, Kazuei; Yokouchi, Hiroshi; Kanazawa, Kenya; Ishida, Takashi; Muto, Satoshi; Ohsugi, Jun; Suzuki, Hiroyuki; Ishikawa, Tetsuo; Kamiya, Kenji; Sakai, Akira

    2015-09-09

    Excess risk of leukemia and brain tumors after CT scans in children has been reported. We performed dicentric chromosome assay (DCAs) before and after CT scan to assess effects of low-dose ionizing radiation on chromosomes. Peripheral blood (PB) lymphocytes were collected from 10 patients before and after a CT scan. DCA was performed by analyzing either 1,000 or 2,000 metaphases using both Giemsa staining and centromere-fluorescence in situ hybridization (Centromere-FISH). The increment of DIC formation was compared with effective radiation dose calculated using the computational dosimetry system, WAZA-ARI and dose length product (DLP) in a CT scan. Dicentric chromosome (DIC) formation increased significantly after a single CT scan, and increased DIC formation was found in all patients. A good correlation between the increment of DIC formation determined by analysis of 2,000 metaphases using Giemsa staining and those by 2,000 metaphases using Centromere-FISH was observed. However, no correlation was observed between the increment of DIC formation and the effective radiation dose. Therefore, these results suggest that chromosome cleavage may be induced by one CT scan, and we recommend 2,000 or more metaphases be analyzed in Giemsa staining or Centromere-FISH for DCAs in cases of low-dose radiation exposure.

  13. 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.

  14. 3D Reconstruction in Spiral Multislice CT Scans

    Directory of Open Access Journals (Sweden)

    M. Ghafouri

    2005-08-01

    Full Text Available Introduction & Background: The rapid development of spiral (helical computed tomography (CT has resulted in exciting new applications for CT. One of these applications, three-dimensional (3D CT with volume ren-dering, is now a major area of clinical and academic interest. One of the greatest advantages of spiral CT with 3D volume rendering is that it provides all the necessary information in a single radiologic study (and there-fore at the lowest possible price in cases that previously required two or more studies. Three-dimensional vol-ume rendering generates clinically accurate and immediately available images from the full CT data set with-out extensive editing. It allows the radiologist and clinician to address specific questions concerning patient care by interactively exploring different aspects of the data set. Three-dimensional images integrate a series of axial CT sections into a form that is often easier to interpret than the sections themselves and can be made to appear similar to other more familiar images such as catheter angiograms. The data are organized into a 3D matrix of volume elements (voxels. The screen of the computer monitor is a 2D-surface composed of discrete picture elements (pixels. Presenting what is stored in memory (ie, floating within the monitor on a 2D-screen is a challenge, but it is the very problem that 3D reconstruc-tion software has creatively solved. Voxel selection is usually accomplished by projecting lines (rays through the data set that correspond to the pixel matrix of the desired 2D image. Differences in the images produced with various 3D rendering techniques are the result of variations in how voxels are selected and weighted. In this article, I compare 3D volume rendering of spiral CT data with other rendering techniques (shaded surface display, maximum intensity projection and present a brief history of 3D volume rendering and discuss the im-plementation of this promising technology in terms of

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

    Science.gov (United States)

    Wang, Tonghe; Zhu, Lei

    2016-09-01

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

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

    DEFF Research Database (Denmark)

    Ding, Ming; Odgaard, A; Hvid, I

    1999-01-01

    Volume fraction, the single most important parameter in describing trabecular microstructure, can easily be calculated from three-dimensional reconstructions of micro-CT images. This study sought to quantify the accuracy of this measurement. One hundred and sixty human cancellous bone specimens...... 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...

  17. Relationship between Hounsfield unit in CT scan and gray scale in CBCT

    Science.gov (United States)

    Kamaruddin, Noorshaida; Rajion, Zainul Ahmad; Yusof, Asilah; Aziz, Mohd Ezane

    2016-12-01

    Cone-beam computed tomography (CBCT) is an imaging system which has advantages over computed tomography (CT). Recently, CBCT has become widely used for oral and maxillofacial imaging. 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 (in vitro) study was to investigate the relationship between gray scale in CBCT and HU in CT scan. In this descriptive study, the anthropomorphic head phantom was scanned with CBCT and CT scanner. Gray scales and HUs were detected on images at the crown of the teeth, trabecular and cortical bone of mandible. The images were analyzed to obtain the gray scale value and HU value. The obtained value then used to investigate the relationship between CBCT gray scales and HUs. For the statistical analysis, t-test, Pearson's correlation and regression analysis were used. The differences between the gray scale of CBCT and HU of CT were statistically not significant, whereas the Pearson's correlation coefficients demonstrated a statistically significant correlation between gray scale of CBCT and HU of CT values. Considering the fact that gray scale in CBCT is important in pre assessment evaluation of bone density before implant treatments, it is recommended because of the lower dose and cost compared to CT scan.

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

    DEFF Research Database (Denmark)

    Johansson, Sofie Lock; Gerner Hansen, Niels-Christian

    2010-01-01

    Adherence to follow-up CT scans in patients with small pulmonary nodules, a retrospective study The Danish National guidelines have since 2008 suggested serial follow-up CT scans at 3, 6, 12, and 24 months for nodules between 5 and 10 mm and at 12 and 24 months for nodules less than 5 mm in accor...... is that management of the follow-up of small nodules did improve in 2008-2009, but adherence to the guidelines was still limited. We will now implement a prospective program for monitoring the adherence to the follow-up CTs.......Adherence to follow-up CT scans in patients with small pulmonary nodules, a retrospective study The Danish National guidelines have since 2008 suggested serial follow-up CT scans at 3, 6, 12, and 24 months for nodules between 5 and 10 mm and at 12 and 24 months for nodules less than 5 mm...... in the four year period 2006-2009. In 72 cases, 19 in 2006-2007 and 51 in 2008-2009, one or more small nodules, with diameter ≤ 10 mm, were detected on CT in patients with no known recent malignant disease. For these patients follow-up was suggested, either with CT or PET-CT. One of the 70 patients from 2008...

  19. AP diameter shows the strongest correlation with CTDI and DLP in abdominal and chest CT.

    LENUS (Irish Health Repository)

    Zarb, Francis

    2010-01-01

    The purpose of this study is to investigate the relationships among cross-sectional diameters, weight and computed tomography (CT) dose descriptors (CTDI and DLP) to identify which is best used as a measure for the establishment of DRLs in CT. Data (gender, weight, cross-sectional diameters, dose descriptors) from 56 adult patients attending for either a CT examination of the abdomen or chest was obtained from two spiral CT units using automatic milliampere modulation. The AP diameter was demonstrated as the main contributing factor influencing the dose in CT (CTDI: r(2) = 0.269, p-value < or =0.001; DLP: r(2) = 0.260, p-value < or =0.001) since it has a greater correlation with radiation dose than body weight and can thus be its substitute in dose-reduction strategies and establishment of DRLs. The advantages of using the AP diameter are that it can easily be measured prior to scanning or retrospectively from previous CT images. However, further studies on the practicality of this approach are recommended.

  20. Multimodal imaging of the human temporal bone: A comparison of CT and optical scanning techniques

    Science.gov (United States)

    Voie, Arne H.; Whiting, Bruce; Skinner, Margaret; Neely, J. Gail; Lee, Kenneth; Holden, Tim; Brunsden, Barry

    2003-10-01

    A collaborative effort between Washington University in St. Louis and Spencer Technologies in Seattle, WA has been undertaken to create a multimodal 3D reconstruction of the human cochlea and vestibular system. The goal of this project is to improve the accuracy of in vivo CT reconstructions of implanted cochleae, and to expand the knowledge of high-resolution anatomical detail provided by orthogonal-plane optical sectioning (OPFOS). At WUSL, computed tomography (CT) images of the cochlea are used to determine the position of cochlear implant electrodes relative to target auditory neurons. The cochlear implant position is determined using pre- and post-operative CT scans. The CT volumes are cross-registered to align the semicircular canals and internal auditory canal, which have a unique configuration in 3-D space. The head of a human body donor was scanned with a clinical CT device, after which the temporal bones were removed, fixed in formalin and trimmed prior to scanning with a laboratory Micro CT scanner. Following CT, the temporal bones were sent to the OPFOS Imaging Lab at Spencer Technologies for a further analysis. 3-D reconstructions of CT and OPFOS imaging modalities were compared, and results are presented. [Work supported by NIDCD Grants R44-03623-5 and R01-00581-13.

  1. Evaluation of Helical CT Scanning in Judging the Invasion and Metastasis of Gastric Carcinoma

    Institute of Scientific and Technical Information of China (English)

    GAOJianbo; KONGXiangquan; GUOHua; LIShuxin; YANGXuehua; LIYintai; ZHANGZhixu

    2004-01-01

    To determine the accuracy of triphase enhanced helical CT in judging the invasion and metastasis of gastric carcinoma, and to discuss the relation between imaging signs and pathological findings. Methods: Triphase enhanced helical CT scanning was performed in 46 patients with gastric carcinoma. Imaging findings were compared with postoperative pathologic results. Results: (1) The accuracy of helical CT for diagnosing involvement of tunica serosa, lymph node metastasis and distant metastasis was 84.8%, 87.0% and 100~ respectively. (2) CT signs of serosal involvement, lymph node metastasis and distant metastasis were in good accordance with pathological findings (P<0.05). Conclusion: Triphase enhanced helical CT scans can comprehensively and precisely reflect the pathologic characteristics of gastric carcinoma, thus it is a reliable technique for the diagnosis of this disease.

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

    Directory of Open Access Journals (Sweden)

    Tahmineh Razi

    2014-06-01

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

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

    Science.gov (United States)

    Razi, Tahmineh; Niknami, Mahdi; Alavi Ghazani, Fakhri

    2014-01-01

    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.

  4. Volumetric gain of the human pancreas after left partial pancreatic resection: A CT-scan based retrospective study.

    Science.gov (United States)

    Phillip, Veit; Zahel, Tina; Danninger, Assiye; Erkan, Mert; Dobritz, Martin; Steiner, Jörg M; Kleeff, Jörg; Schmid, Roland M; Algül, Hana

    2015-01-01

    Regeneration of the pancreas has been well characterized in animal models. However, there are conflicting data on the regenerative capacity of the human pancreas. The aim of the present study was to assess the regenerative capacity of the human pancreas. In a retrospective study, data from patients undergoing left partial pancreatic resection at a single center were eligible for inclusion (n = 185). Volumetry was performed based on 5 mm CT-scans acquired through a 256-slice CT-scanner using a semi-automated software. Data from 24 patients (15 males/9 females) were included. Mean ± SD age was 68 ± 11 years (range, 40-85 years). Median time between surgery and the 1st postoperative CT was 9 days (range, 0-27 days; IQR, 7-13), 55 days (range, 21-141 days; IQR, 34-105) until the 2nd CT, and 191 days (range, 62-1902; IQR, 156-347) until the 3rd CT. The pancreatic volumes differed significantly between the first and the second postoperative CT scans (median volume 25.6 mL and 30.6 mL, respectively; p = 0.008) and had significantly increased further by the 3rd CT scan (median volume 37.9 mL; p = 0.001 for comparison with 1st CT scan and p = 0.003 for comparison with 2nd CT scan). The human pancreas shows a measurable and considerable potential of volumetric gain after partial resection. Multidetector-CT based semi-automated volume analysis is a feasible method for follow-up of the volume of the remaining pancreatic parenchyma after partial pancreatectomy. Effects on exocrine and endocrine pancreatic function have to be evaluated in a prospective manner. Copyright © 2015 IAP and EPC. Published by Elsevier B.V. All rights reserved.

  5. 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.)

  6. Discrepancy of bone metastases between F-18 FDG PET/CT and bone scan in a patient with prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Seung Jin; Kim, Chul Soo; Byun, Sung Su; Hyun, In Young [Inha University College of Medicine, Incheon (Korea, Republic of)

    2006-10-15

    We report the case of a 73-year-old man who had prostate cancer with bone metastases. Tc-99m HDP Whole body bone scan revealed multiple areas of increased bony uptake consistent with widespread bone metastases. F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) demonstrated mild F-18 FDG uptake in the lymph nodes of neck, abdomen, and pelvis. However, abnormal F-18 FDG uptake was not seen in the skeletal system. Biopsy and immunohistochemical stains of left supraclavicular mass showed metastatic prostate adenocarcinoma. Currently, there are a few reported cases of F-18 FDG PET/CT evaluation of bone metastases in prostate cancer. We discuss the discrepancy between F-18 FDG PET/CT and bone scan in the detection of osseous metastases of prostate cancer.

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

    DEFF Research Database (Denmark)

    Villa, Chiara; Primeau, Charlotte; Hesse, Ulrik

    2017-01-01

    Calculation of the estimated body surface area (BSA) by body height and weight has been a challenge in the past centuries due to lack of a well-documented gold standard. More recently, available techniques such as 3D laser surface scanning and CT scanning may be expected to quantify the BSA...... 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...

  8. 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

  9. Evaluating 3D registration of CT-scan images using crest lines

    Science.gov (United States)

    Ayache, Nicholas; Gueziec, Andre P.; Thirion, Jean-Philippe; Gourdon, A.; Knoplioch, Jerome

    1993-06-01

    We consider the issue of matching 3D objects extracted from medical images. We show that crest lines computed on the object surfaces correspond to meaningful anatomical features, and that they are stable with respect to rigid transformations. We present the current chain of algorithmic modules which automatically extract the major crest lines in 3D CT-Scan images, and then use differential invariants on these lines to register together the 3D images with a high precision. The extraction of the crest lines is done by computing up to third order derivatives of the image intensity function with appropriate 3D filtering of the volumetric images, and by the 'marching lines' algorithm. The recovered lines are then approximated by splines curves, to compute at each point a number of differential invariants. Matching is finally performed by a new geometric hashing method. The whole chain is now completely automatic, and provides extremely robust and accurate results, even in the presence of severe occlusions. In this paper, we briefly describe the whole chain of processes, already presented to evaluate the accuracy of the approach on a couple of CT-scan images of a skull containing external markers.

  10. CT Scan Mapping of Splenic Flexure in Relation to Spleen and its Clinical Implications.

    Science.gov (United States)

    Saber, Alan A; Dervishaj, Ornela; Aida, Samer S; Christos, Paul J; Dakhel, Mahmoud

    2016-05-01

    Splenic flexure mobilization is a challenging step during left colon resection. The maneuver places the spleen at risk for injury. To minimize this risk, we conducted this study for CT scan mapping of splenic flexure in relation to the spleen. One hundred and sixty CT scans of abdomen were reviewed. The level of the splenic flexure was determined in relation to hilum and lower pole of spleen. These levels were compared with patient demographics. Statistical analysis was performed using Fisher's exact test. The splenic flexure was above the hilum of the spleen in 95 patients (67.86%), at the splenic hilum level in 11 patents (7.88%), between the hilum and lower pole of the spleen in 12 (8.57%), at the lower pole of the spleen in 15 (10.7%) patients and 7 (5%) patients has a splenic flexure that lied below the lower pole of the spleen. Patient demographics showed no statistical significance in regard to splenic flexure location. Splenic flexure lies above the hilum of the spleen in majority of patients. This should be considered as part of operative strategies for left colon resection.

  11. Axial segmentation of lungs CT scan images using canny method and morphological operation

    Science.gov (United States)

    Noviana, Rina; Febriani, Rasal, Isram; Lubis, Eva Utari Cintamurni

    2017-08-01

    Segmentation is a very important topic in digital image process. It is found simply in varied fields of image analysis, particularly within the medical imaging field. Axial segmentation of lungs CT scan is beneficial in designation of abnormalities and surgery planning. It will do to ascertain every section within the lungs. The results of the segmentation are accustomed discover the presence of nodules. The method which utilized in this analysis are image cropping, image binarization, Canny edge detection and morphological operation. Image cropping is done so as to separate the lungs areas, that is the region of interest. Binarization method generates a binary image that has 2 values with grey level, that is black and white (ROI), from another space of lungs CT scan image. Canny method used for the edge detection. Morphological operation is applied to smoothing the lungs edge. The segmentation methodology shows an honest result. It obtains an awfully smooth edge. Moreover, the image background can also be removed in order to get the main focus, the lungs.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1988-06-01

    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).

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

    NARCIS (Netherlands)

    Sierink, J.C.; Saltzherr, T.P.; Beenen, L.F.; Luitse, J.S.; Hollmann, M.W.; Reitsma, J.B.; Edwards, M.J.R.; Hohmann, J.; Beuker, B.J.; Patka, P.; Suliburk, J.W.; Dijkgraaf, M.G.; Goslings, J.C.

    2012-01-01

    BACKGROUND: Computed tomography (CT) scanning has become essential in the early diagnostic phase of trauma care because of its high diagnostic accuracy. The introduction of multi-slice CT scanners and infrastructural improvements made total-body CT scanning technically feasible and its usage is curr

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

    NARCIS (Netherlands)

    J.C. Sierink (Joanne); T.P. Saltzherr (Teun); L.F.M. Beenen (Ludo); J.S.K. Luitse; M.W. Hollmann (Markus); J.B. Reitsma (Johannes); M.J.R. Edwards (Michael); J. Hohmann (Joachim); B.J.A. Beuker (Benn); P. Patka (Peter); J.W. Suliburk (James); M.G.W. Dijkgraaf (Marcel); J.C. Goslings (Carel)

    2012-01-01

    textabstractBackground: Computed tomography (CT) scanning has become essential in the early diagnostic phase of trauma care because of its high diagnostic accuracy. The introduction of multi-slice CT scanners and infrastructural improvements made total-body CT scanning technically feasible and its u

  15. 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)

  16. Clinical evaluation of a dose monitoring software tool based on Monte Carlo Simulation in assessment of eye lens doses for cranial CT scans

    Energy Technology Data Exchange (ETDEWEB)

    Guberina, Nika; Suntharalingam, Saravanabavaan; Nassenstein, Kai; Forsting, Michael; Theysohn, Jens; Wetter, Axel; Ringelstein, Adrian [University Hospital Essen, Institute of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany)

    2016-10-15

    The aim of this study was to verify the results of a dose monitoring software tool based on Monte Carlo Simulation (MCS) in assessment of eye lens doses for cranial CT scans. In cooperation with the Federal Office for Radiation Protection (Neuherberg, Germany), phantom measurements were performed with thermoluminescence dosimeters (TLD LiF:Mg,Ti) using cranial CT protocols: (I) CT angiography; (II) unenhanced, cranial CT scans with gantry angulation at a single and (III) without gantry angulation at a dual source CT scanner. Eye lens doses calculated by the dose monitoring tool based on MCS and assessed with TLDs were compared. Eye lens doses are summarized as follows: (I) CT angiography (a) MCS 7 mSv, (b) TLD 5 mSv; (II) unenhanced, cranial CT scan with gantry angulation, (c) MCS 45 mSv, (d) TLD 5 mSv; (III) unenhanced, cranial CT scan without gantry angulation (e) MCS 38 mSv, (f) TLD 35 mSv. Intermodality comparison shows an inaccurate calculation of eye lens doses in unenhanced cranial CT protocols at the single source CT scanner due to the disregard of gantry angulation. On the contrary, the dose monitoring tool showed an accurate calculation of eye lens doses at the dual source CT scanner without gantry angulation and for CT angiography examinations. The dose monitoring software tool based on MCS gave accurate estimates of eye lens doses in cranial CT protocols. However, knowledge of protocol and software specific influences is crucial for correct assessment of eye lens doses in routine clinical use. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-08-15

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

  18. 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

    with a CT image and also use the CT for attenuation correction. In any practical hospital setting, 1 hour is too long to occupy the scanner bed and a second CT procedure thus becomes necessary. This study tries to validate to what extent the dose/quality of the second CT scan can be lowered, without...... 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...... within predetermined error limits. For a hot sphere to background activity concentration ratio of 1:5, the average uptake (normalised by the time corrected input activity concentration) in a sphere of 6 cm3 was found to be 0.90 ± 0.08 for the standard scan, yielding a dose of 5.5 mGy, and 0.90 ± 0...

  19. Prognostic Value of Gastric Bare Area & Left Adrenal Gland Involvement in Acute Pancreatitis on Abdominal CT SCAN

    Directory of Open Access Journals (Sweden)

    Saeed Naghibi

    2009-01-01

    enhanced CT. "nStatistical analysis was performed with software SPSS ver 11.0 and the results were calculated and expressed with Fisher’s exact and chi square tests. "nResults: On CT scan, GBAI was found in 26/50 patients (51.2% and LAGI was 18/50 patients (28.7%.There were significant differences for complications (p<0.001 & p<0.01 and mortality in patients with GBAI and LAGI in our patients as compared with patients without these involvement. The sensitivity and specificity of GBAI for predicting complications were 48.3% and 91.4%, respectively and 77.2% & 88.6%, respectively for predicting mortality. The sensitivity and specificity of LAGI for predicting complications were 36.8% and 94.4%, respectively and 71.5% & 93%, respectively for predicting mortality. (In our study the overall complications rate was 63% and the mortality rate was 6.2%. "nConclusion: The gastric bare area is where the posterior wall of the fundus and subcarinal portion of the stomach is uncovered by the visceral peritoneum and the left anterior renal fascia, initially a barrier, eventually breaks down and permits the spread of inflammation fro the anterior pararenal space into the left perirenal space resulting in LAGI. This study shows that GBAI and LAGI are good predictors of morbidity and mortality in this group, showing high specificity, although with low sensitivity compared with specificity. The GBAI and LAGI can be easily applied to evaluate the prognosis of patients with acute pancreatitis in clinical setting compared with the clinical & imaging scoring systems, e.g., Ranson criteria and APACHI and Balthazar scoring systems. Keywords: CT scan, Acute Pancreatitis, Gastric Bare Area, Adrenal Gland  

  20. 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.)

  1. Practice of CT scanning;Pratique de la tomodensitometrie

    Energy Technology Data Exchange (ETDEWEB)

    Kerviler, E. de [Assistance Publique - Hopitaux de Paris, Saint Louis, 75 - Paris (France)

    2009-10-15

    The proliferation of CT examinations necessitates the use of indicators of standard dose and reference levels. The dose.length product calculated from the computed tomography dose index (C.T.D.I.) is available on every recent machine and must appeared in the radiological report. Several techniques easily accessible to the console as the dose modulation, allow to reduce the dose to the patient. The combined use of these techniques allows dose reductions of more than 50%. The most important dose reductions are got in the organs with a strong contrast (lungs, sinus of the face). (N.C.)

  2. 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.

  3. Single energy micro CT SkyScan 1173 for the characterization of urinary stone

    Science.gov (United States)

    Fitri, L. A.; Asyana, V.; Ridwan, T.; Anwary, F.; Soekersi, H.; Latief, F. D. E.; Haryanto, F.

    2016-08-01

    A urinary stone is a solid piece of material produced from crystallization of excreted substances in the urine. Knowledge of the composition of urinary stones is essential to determine the suitable treatment for the patient. The aim of this research was to characterize urinary stones using single energy micro CT SkyScan 1173. Six human urinary stones were scanned in vitro using 80 kV in micro CT SkyScan 1173. The produced projection, images, were reconstructed using NRecon (in-house software from SkyScan). The images of urinary stones were analyzed using CT Analyser (CT An) to obtain information of the internal structure and the Hounsfield Unit (HU) value to determine the information regarding the composition of the urinary stones, respectively. The average HU values from certain region of interests in the same slice were compared with spectral curves of known materials from National Institute of Standards and Technology (NIST). From the analysis, the composition of the six scanned stones were obtained. Two stones are composed of cystine, two are composed of struvite, two other stones are composed of struvite+cystine. In conclusion, the single energy micro CT with 80 kV can be used identifying cystine and struvite urinary stone.

  4. 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.

  5. Computer-aided detection and quantification of cavitary tuberculosis from CT scans

    Science.gov (United States)

    Xu, Ziyue; Bagci, Ulas; Kubler, Andre; Luna, Brian; Jain, Sanjay; Bishai, William R.; Mollura, Daniel J.

    2013-01-01

    determined precisely. While accuracy of the authors’ cavity detection algorithm was 94.61%, airway detection part of the proposed methodology showed even higher performance by 99.8%. Dice similarity coefficients for cavitary segmentation experiments were found to be approximately 99.0% with respect to the reference truths provided by two expert radiologists (blinded to their evaluations). Moreover, the authors noted that volume derived from the authors’ segmentation method was highly correlated with those provided by the expert radiologists (R2 = 0.99757 and R2 = 0.99496, p < 0.001, with respect to the observer 1 and observer 2) with an interobserver agreement of 98%. The authors quantitatively confirmed that cavity formation was positioned by the nearby bronchial-tree after exploring the respective spatial positions based on the minimum distance measurement. In terms of efficiency, the core algorithms take less than 2 min on a linux machine with 3.47 GHz CPU and 24 GB memory. Conclusion: The authors presented a fully automatic method for cavitary TB detection, quantification, and evaluation. The performance of every step of the algorithm was qualitatively and quantitatively assessed. With the proposed method, airways and cavities were automatically detected and subsequently delineated in high accuracy with heightened efficiency. Furthermore, not only morphological information of cavities were obtained through the authors’ proposed framework, but their spatial relation to airways, and longitudinal analysis was also provided to get further insight on cavity formation in tuberculosis disease. To the authors’ best of knowledge, this is the first study in computerized analysis of cavitary tuberculosis from CT scans. PMID:24320475

  6. 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.

  7. EFEKTIFITAS VARIASI NILAI WINDOW LEVEL TERHADAP KUALITAS HASIL CT SCAN THORAX LUNG WINDOW

    OpenAIRE

    dani, Rahma

    2014-01-01

    EFEKTIFITAS VARIASI NILAI WINDOW LEVEL TERHADAP KUALITAS HASIL CT SCAN THORAX LUNG WINDOW Rahmadani Jurusan Fisika, FMIPA, Universitas Hasanuddin, Makassar 90245, Indonesia Pembimbing Utama : Prof. Dr. H. Halmar Halide, M.Sc Pembimbing Pertama : Dahlang Tahir, M.Sc. Phd ABSTRAK Telah dilakukan penelitian untuk mengetahui efek variasi nilai window level terhadap kualitas hasil CT Scann thorax lung window dengan pengaturan window width 1000,1500, 2000 dengan varias...

  8. Detection of Dental Pathologies in Routine Paranasal CT Scans: A Retrospective Study.

    Science.gov (United States)

    Bulbul, Erdogan; Yanik, Bahar; Demirpolat, Gulen

    2017-07-01

    Multidetector Computed Tomography (MDCT) is a widespread method for evaluating paranasal sinuses and nasal cavity in daily practice. The maxillary teeth are in field of view in a paranasal sinus CT scan and it is possible to detect dental pathologies with CT. To determine the incidence of maxillary teeth pathologies in routine paranasal sinus CT scans. A retrospective study was conducted. Consecutive 395 paranasal sinus CT scans were evaluated. All CT images were obtained with a 64 detector-CT. Patients with previous facial trauma, operation, invasive tumors and repeated exams were excluded. Detected findings were classified as "tooth loss, dental restorations or procedures and dental pathologies (carious lesions, dental developmental anomalies, periapical lesions and periodontal diseases). The proportion of findings was reported as simple percentiles. Three hundred and eighty-four CT scans were included in the study. Dental restorations or procedures were determined in 129 (33.5%) patients. A total of 34 (8.8%) patients had normal teeth count and morphology. A total of 264 (64.3%) patients had at least one tooth loss. A total of 195 (51%) patients had at least one or more dental pathology. Number of dental carious lesions, dental developmental anomalies, periapical lesions and periodontal disease were 104 (27.0%), 78 (14.3%), 46 (11.9%), 44 (11.4%), respectively. Dental pathologies were encountered in more than half of the patients. Detecting dental pathologies may prevent tooth loss and improve oral health. The radiologist should keep in mind dental pathologies while evaluating paranasal sinus CT in daily practice.

  9. Efficacy of CT scanning in a group of 174 patients with orthopedic and musculoskeletal problems

    Energy Technology Data Exchange (ETDEWEB)

    Griffiths, H.J.; Hamlin, D.J.; Kiss, S.; Lovelock, J.

    1981-11-01

    One hundred and seventy-four patients with orthopedic and musculoskeletal problems received computed tomography (CT) scans between January 1979 and July 1980. There were 34 trauma patients, 35 patients with known or suspected primary tumors, 20 patients with metastases, 18 patients with suspected spinal stenosis, 25 patients with disc problems, five patients with infections, 13 children with congenital anomalies, and 24 patients with miscellaneous problems. The CT scans proved useful in all the pediatric cases, 97% of the trauma patients, and in the majority of patients with tumors. It appears that absolute indications for CT scanning in orthopedic patients include acute trauma to the spine, pelvis, hip, and shoulder girdles as well as in children with congenital spinal anomalies. Relative indications include determining the extent of the tumor and also aiding in the correct approach for biopsying a lesion.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1983-04-01

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

  11. Relationship between lower third molar and mandibular canal; Preoperative evaluation using CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Itou, Masaki; Miyagishima, Toshio; Onizuka, Hiroyuki (Fujieda City Shida General Hospital, Shizuoka (Japan)); Takagi, Norio

    1994-01-01

    The mandibular canal is often closely related to the lower third molars. During the surgical removal of the third molar, the inferior alveolar nerve in the canal is sometimes damaged leading to impaired sensation in the lower lip. This is one of the most unpleasant postoperative complications. The buccolingual relationship between the lower third molar and the mandibular canal cannot be diagnosed by ortho-pantomography although preoperative evaluation must be carried out radiologically. In present study, the relationship was determined by using CT scan. Forty-seven lower third molars of 35 patients were evaluated preoperatively by CT scan. The mandibular canal of all cases overlapped with the third molar on ortho-pantomography. CT scan was taken in two ways. The first was the Tragion-Menton plane which was nearly parallel to the canal at the apex of the third molar. The second was the plane of the axis of the third molar. Axial CT scan was taken when the third molar erupted horizontally, and coronal CT scan was done when the molar erupted vertically. CT scan examination exactly revealed the position of the mandibular canal in relation to the root of the third molar. The canal was located buccally to the roots in 55 percent of cases, apicobuccally in 6 percent, apically in 23 percent, apicolingually in 6 percent, lingually in 2 percent, and between roots in 6 percent. The results of the present study were consistent with previous reports. In 12 cases, the inferior alveolar neurovascular bundle was visible during operation. It was visible in only 2 of 22 cases when the canal was located buccally. It was visible, on the other hand, in all cases in which the canal was located apicolingually, lingually, and between roots. It also tended to be visible when the canal overlapped more strongly with the third molar on preoperative ortho-pantomography. (author).

  12. Initial brain CT scan and shunting outcomes in children with hydrocephalus

    Directory of Open Access Journals (Sweden)

    Andi Anita Utami

    2013-04-01

    Full Text Available Background Hydrocephalus is one of the most common clinical conditions affecting the central nervous system, with a congenital hydrocephalus incidence of 3-4 per 1000 births. Incidence of acquired types of hydrocephalus is unknown. Brain computerised tomography (CT scan can be used to assess the size of ventricles and other structures. Shunting has long been performed to alleviate hydrocephalus. Shunting has dramatically changed the outlook of children with hydrocephalus, with many of them having normal life expectancies and attaining normal intelligence. Objective To determine the outcomes of shunting in children with hydrocephalus based on initial brain CT scan. Methods We performed a cross-sectional study in Dr. Kariadi Hospital. Initial brain CT scan data were collected from the medical records of children admitted to the Neurosurgery Ward for ventriculoperitoneal (VP shunt surgery from January 2009 to December 2010. We studied the brain CT scan findings before VP shunt surgery and the outcomes of the children after VP shunt surgery. Radiological findings were determined by a radiologist responsible at that time. Results This study consisted of 30 subjects, 19 boys and 11 girls. Initial brain CT scans to assess disease severity revealed the following conditions: lateral ventricle dilatation in 7 subjects, lateral and third ventricle dilatation in 16 subjects, and lateral, third and fourth ventricle dilatation in 7 subjects. After VP shunt surgery, 3 subjects in the lateral, third and fourth ventricle dilatation category died. They were grouped according to their condition. Group 1 consisted of subjects with only lateral ventricle dilatation and subjects with lateral and third ventricle dilatation (23 subjects, while group 2 consisted of subjects with lateral, third and fourth ventricle dilatation (7 subjects. More survivors were found in group 1 than those in group 2. Conclusion Less severe initial brain CT scan findings are associated with

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2008-07-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-08-15

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

  15. A comparative study of the diagnostic accuracy on Waters view with CT scan in detecting midface fractures

    OpenAIRE

    Panjnoush M.; Shirani Gh.; Jozghanbari P.

    2006-01-01

    Background and Aim: In recent years, CT scan has become available as an alternative to conventional radiography. To date, the utility of Waters view in detecting midface fractures has been rarely evaluated. The aim of this study was to compare the diagnostic accuracy and reliability of Waters radiography with CT scan in detecting midface fractures. Materials and Methods: In this tests evaluation study, waters view and CT scan were performed for 42 patients with midface fracture admitted to ma...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. CT-scanning of the temporal bone in an inner ear malformation

    Energy Technology Data Exchange (ETDEWEB)

    Murata, K.; Hosoi, H.; Isono, M.; Ohta, F. (Kinki Univ., Higashi-Osaka, Osaka (Japan))

    1982-05-01

    CT-scanning of the temporal bone revealed a fine contour of the inner ear anomaly in a 8-year-old boy with total deafness on the right. In the inner ear there was a globular mass with a small protrusion anteriorly and with a probably immature superior semi-circular canal. The globular mass was considered to be the utriculosaccular capsule, and the anterior protrusion to be an incipient cochlear duct. CT-scanning of the temporal bone may bring significant progress in diagnosis of inner ear anomalies. Detailed configuration of an inner ear may be shown before histological examination.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    This work deals with the study of stability and material investigation for manufacturing of step gauges for CT scanning verification. Four replica step gauges were fabricated using a bisacryl material for dental applications and the stability over five months was monitored using a tactile CMM....... The material was unstable, probably due to a modification of the chemical composition which lowered the hardness. New step gauges were manufactured through milling. Polyetheretherketone (PEEK) and Polyp-phenylenesulphide (PPS with 40% glass) fulfil the requirements regarding hardness and mechanical properties...... and two series of five step gauges (one series for each material) were manufactured by milling. Results show a significant improvement in terms of form stability and surface geometry quality of the new step gauges with respect to the replica step gauges in Luxabite, as reported below....

  19. Clinicopathological evaluation of the cases with positive ependymal enhancement by CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Atsuhiro; Akagi, Katsuhito; Horibe, Kunio; Yamasaki, Mami; Kurata, Akihiko

    1988-06-01

    A clinicopathological analysis of ependymal enhancement on CT scans found in 5 patients with neoplasm (N), 3 with infection (I), 2 with cerebral hemorrhage (CH), and 2 with cerebral infarction (CI) yielded the following findings. Ependymal enhancement was diffusely or partially observed during the clinical course. In the N group, ependymal enhancement was associated with positive cerebrospinal fluid in cytology and therapeutic response in 4 patients. Characteristic ventricular opacification was observed in 3 patients. In the groups of N and I, mortality rate was high (87 %), probably showing ependymal enhancement to be a sign of unfavorable prognosis. The groups of CH and CI had ventricular or intracerebral hemorrhage with rupture in ventricles and massive infarction. In evauable 5 patients at autopsy, major histological changes surrounding the ventricular wall included gliosis in the ependymal and subependymal layers, ependymal infiltration of tumor cells, destruction of ependyma, and neovascularization. These findings suggest some disturbance in ependymal and periventricular circulation. (Namekawa, K.).

  20. 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....

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

    Energy Technology Data Exchange (ETDEWEB)

    Boellaard, Thierry N., E-mail: t.n.boellaard@amc.uva.nl [Department of Radiology, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands); Haan, Margriet C. de, E-mail: m.c.dehaan@amc.uva.nl [Department of Radiology, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands); Venema, Henk W., E-mail: h.w.venema@amc.uva.nl [Department of Radiology, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands); Department of Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands); Stoker, Jaap, E-mail: j.stoker@amc.uva.nl [Department of Radiology, Academic Medical Center, University of Amsterdam, PB 22660, 1100 DD Amsterdam (Netherlands)

    2013-08-15

    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.

  2. Three-dimensional image analysis of the skull using variable CT scanning protocols-effect of slice thickness on measurement in the three-dimensional CT images

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Ho Gul; Kim, Kee Deog; Park, Hyok; Kim, Dong Ook; Jeong, Hai Jo; Kim, Hee Joung; Yoo, Sun Kook; Kim, Yong Oock; Park, Chang Seo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2004-07-15

    To evaluate the quantitative accuracy of three-dimensional (3D) images by mean of comparing distance measurements on the 3D images with direct measurements of dry human skull according to slice thickness and scanning modes. An observer directly measured the distance of 21 line items between 12 orthodontic landmarks on the skull surface using a digital vernier caliper and each was repeated five times. The dry human skull was scanned with a Helical CT with various slice thickness (3, 5, 7 mm) and acquisition modes (Conventional and Helical). The same observer measured corresponding distance of the same items on reconstructed 3D images with the internal program of V-works 4.0 (Cybermed Inc., Seoul, Korea). The quantitative accuracy of distance measurements were statistically evaluated with Wilcoxons' two-sample test. 11 line items in Conventional 3 mm, 8 in Helical 3 mm, 11 in Conventional 5 mm, 10 in Helical 5 mm, 5 in Conventional 7 mm and 9 in Helical 7 mm showed no statistically significant difference. Average difference between direct measurements and measurements on 3D CT images was within 2 mm in 19 line items of Conventional 3 mm. 20 of Helical 3 mm, 15 of Conventional 5 mm, 18 of Helical 5 mm, 11 of Conventional 7 mm and 16 of Helical 7 mm. Considering image quality and patient's exposure time, scanning protocol of Helical 5 mm is recommended for 3D image analysis of the skull in CT.

  3. Analysis of the abdominal musculo-aponeurotic anatomy in rectus diastasis: comparison of CT scanning and preoperative clinical assessment with direct measurement intraoperatively.

    Science.gov (United States)

    Emanuelsson, P; Dahlstrand, U; Strömsten, U; Gunnarsson, U; Strigård, K; Stark, B

    2014-08-01

    To evaluate and compare the consistency of agreement of two methods for measuring abdominal rectus diastasis (ARD), preoperative computed tomography (CT) scanning and preoperative clinical assessment were compared with direct measurement intraoperatively. Fifty-five consecutive patients were retrieved from an ongoing prospective randomised trial comparing two operative techniques for the repair of ARD. All patients underwent a preoperative clinical assessment and CT scan, and the results were compared with intraoperative measurement of the ARD width. Agreement between methods was described with Bland-Altman plots (BA plots) and calculated using Lin's Concordance Correlation Coefficient (CCC). The median width of the diastasis was 4.0 cm in the upper midline and 3.0 cm in the lower midline for the intraoperative measurement. BA plots showed that measurements on CT and intraoperatively are not in agreement in the lower midline, whereas the agreement was stronger between the clinical and the intraoperative method. The CCC was higher for clinical vs. intraoperative measurement (0.479) than for CT vs. intraoperative measurement (-0.002) in the lower midline, although the agreement was over all low. CT scanning underestimated the width of the ARD when compared to 87 % of preoperative clinical assessments, and 83 % of intraoperative measurements. Preoperative clinical assessment overestimated ARD in 35 % when compared with intraoperative measurements. Clinical assessment prior to surgery provides more accurate information than CT scanning in the assessment of ARD width. CT scanning underestimates ARD width when compared with intraoperative measurement.

  4. The Impact of Sources of Variability on Parametric Response Mapping of Lung CT Scans.

    Science.gov (United States)

    Boes, Jennifer L; Bule, Maria; Hoff, Benjamin A; Chamberlain, Ryan; Lynch, David A; Stojanovska, Jadranka; Martinez, Fernando J; Han, Meilan K; Kazerooni, Ella A; Ross, Brian D; Galbán, Craig J

    2015-09-01

    Parametric response mapping (PRM) of inspiration and expiration computed tomography (CT) images improves the radiological phenotyping of chronic obstructive pulmonary disease (COPD). PRM classifies individual voxels of lung parenchyma as normal, emphysematous, or nonemphysematous air trapping. In this study, bias and noise characteristics of the PRM methodology to CT and clinical procedures were evaluated to determine best practices for this quantitative technique. Twenty patients of varying COPD status with paired volumetric inspiration and expiration CT scans of the lungs were identified from the baseline COPD-Gene cohort. The impact of CT scanner manufacturer and reconstruction kernels were evaluated as potential sources of variability in PRM measurements along with simulations to quantify the impact of inspiration/expiration lung volume levels, misregistration, and image spacing on PRM measurements. Negligible variation in PRM metrics was observed when CT scanner type and reconstruction were consistent and inspiration/expiration lung volume levels were near target volumes. CT scanner Hounsfield unit drift occurred but remained difficult to ameliorate. Increasing levels of image misregistration and CT slice spacing were found to have a minor effect on PRM measurements. PRM-derived values were found to be most sensitive to lung volume levels and mismatched reconstruction kernels. As with other quantitative imaging techniques, reliable PRM measurements are attainable when consistent clinical and CT protocols are implemented.

  5. An Inflammatory Dentigerous Cyst Shows Rim Uptake on Bone Scan: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Son, Hye Joo; Jeong, Young Jin; Jeong, Jin Sook; Kang, Doyoung [Dong-A Univ. Medical Center, Busan (Korea, Republic of)

    2014-03-15

    Dentigerous cysts are developmental odontogenic jaw cysts, commonly manifesting in the 2nd and 3rd decades of life. This article presents an extremely rare case of dentigerous cyst showing increased uptake in the peripheral rim on bone scan. Herein, we discuss the clinical, radiographic, and histologic features of dentigerous cysts as well as the pathological mechanism underlying their activities on the bone scan. Bone scan was a sensitive tool for detecting the biologic activity of dentigerous cyst in our case.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-08-15

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

  7. Complementary role of CT and In-111 leukocyte scans in the diagnosis of infected hematoma and thrombosis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, E.E.; Pjura, G.A.; Floyd, W.; Raval, B.; Sandler, C.; Gobuty, A.H.

    1984-01-01

    Patients with traumatic hematomas or those with indwelling catheters who subsequently develop fever and sepsis without clinical localizing signs to indicate an inflammatory focus can present a diagnostic dilemma. Early diagnosis of an infected hematoma or thrombus is important to optimal management. CT can provide, exquisite delineation of anatomy identifying and localizing a post-traumatic fluid collection but cannot reliably distinguish hematoma from abscess in all cases. A thrombus at a catheter tip may be too small to be resolved; when identified, the question of infection again remains. In-111 leukocyte scanning provides a method for identifying or ruling out infection in these situations. The authors performed In-111 leukocyte scans on 15 patients with indwelling catheters. Five of these patients were febrile with positive blood cultures. In-111 leukocyte scans showed positive findings in 8 patients: 5 showed surgically confirmed infected hematomas in the abdomen (3 in the pelvis, 1 in a kidney, 1 in the splenic bed), and 3 showed infected thrombosis in catheter tips. The authors conclude that CT scanning and In-111 leukocyte scanning play complementary roles in the evaluation of traumatic hematomas and thrombosis, the former providing precise anatomic delineation and the latter providing evidence of inflammation.

  8. CT imaging before transcatheter aortic valve implantation (TAVI) using variable helical pitch scanning and its diagnostic performance for coronary artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Shunsuke; Yamada, Yoshitake; Hashimoto, Masahiro; Okamura, Teppei; Jinzaki, Masahiro [Keio University School of Medicine, Department of Diagnostic Radiology, Shinanomachi, Shinjuku-ku, Tokyo (Japan); Yamada, Minoru [Keio University School of Medicine, Research Park, Tokyo (Japan); Yashima, Fumiaki; Hayashida, Kentaro; Fukuda, Keiichi [Keio University School of Medicine, Department of Cardiology, Tokyo (Japan)

    2017-05-15

    To evaluate the effectiveness of CT before TAVI using variable helical pitch (VHP) scanning and its diagnostic performance for coronary artery disease (CAD). Sixty patients (84.4 ± 4.6 years) scheduled for TAVI underwent CT using VHP scanning with the contrast material (CM) volume calculated as scanning time x weight [kg] x 0.06 mL. Retrospective electrocardiography (ECG)-gated scanning was utilized to examine the thorax, and non-ECG-gated scanning of the abdomen immediately followed. We analyzed CT attenuation values of the coronary arteries, aorta, iliac and femoral arteries. The coronary CT angiography images were evaluated for the presence of stenosis (≥50 %); invasive coronary angiography served as a reference standard. The average attenuations of all of the arteries were greater than 400 HU. We could evaluate the peripheral access vessels and dimensions of the ascending aorta, aortic root, and aortic annulus in all patients. The average volume of CM was 38.7 ± 8.5 mL. On per-patient and vessel analysis, CT showed 91.7 % and 89.5 % sensitivity, and 91.3 % and 97.4 % negative predictive value (NPV). CT using VHP scanning with an average CM volume of 38.7 mL is useful before TAVI and had a high sensitivity and NPV in excluding obstructive CAD. (orig.)

  9. Epidemiological and clinical studies on aseptic meningitis in 377 cases, 3. A study on brain CT scan in acute phase

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, Masaaki; Kondo, Tomio; Takashima, Akira; Kono, Shinya; Yamashina, Manabu (Ogaki Shimin Hospital, Gifu (Japan))

    1984-02-01

    Brain CT scan performed in the acute phase of aseptic meningitis in 88 cases revealed abnormal findings in 5 consisting of 2 of cerebral edema, 2 of subdural hygroma and one of cerebral atrophy. Clinical findings showed no particular relation to the age, but cerebral edema was observed in the cases of possible cephalomeningitis diagnosed on the basis of accompanying convulsion and disturbance of consciousness. Abnormal findings were associated with 25% of symptoms diagnosed more than 4 days after onset.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-07-01

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

  11. Acetabular orientation variability and symmetry based on CT scans of adults

    Energy Technology Data Exchange (ETDEWEB)

    Lubovsky, Omri; Liebergall, Meir; Khoury, Amal [Hadassah-Hebrew University Medical Center, Orthopedic Surgery Complex, Jerusalem (Israel); Peleg, Eran [Hadassah-Hebrew University Medical Center, Department of Medical Engineering, Jerusalem (Israel); Joskowicz, Leo [Hebrew University of Jerusalem, School of Engineering and Computer Science, Jerusalem (Israel)

    2010-09-15

    Understanding acetabular orientation is important in many orthopaedic procedures. Acetabular orientation, usually described by anteversion and abduction angles, has uncertain measurement variability in adult patients. The goals of this study are threefold: (1) to describe a new method for computing patient-specific abduction/anteversion angles from a single CT study based on the identification of anatomical landmarks and acetabular rim points; (2) to quantify the inaccuracies associated with landmark selection in computing the acetabular angles; and (3) to quantify the variability and symmetry of acetabular orientation. A total of 25 CT studies from adult patients scanned for non-orthopaedic indications were retrospectively reviewed. The patients were randomly selected from the hospital's database. Inclusion criteria were adults 20-65 years of age. Acetabular landmark coordinates were identified by expert observers and tabulated in a spreadsheet. Two sets of calculations were done using the data: (1) computation of the abduction and anteversion for each patient, and (2) evaluation of the variability of measurements in the same individual by the same surgeon. The results were tabulated and summary statistics computed. This retrospective study showed that acetabular abduction and anteversion angles averaged 54 and 17 , respectively, in adults. A clinically significant intra-patient variability of >20 was found. We also found that the right and left side rim plane orientation were significantly correlated, but were not always symmetric. A new method of computing patient-specific abduction and anteversion angles from a CT study of the anterior pelvic plane and the left and right acetabular rim planes was reliable and accurate. We found that the acetabular rim plane can be reliably and accurately computed from identified points on the rim. The novelty of this work is that angular measurements are performed between planes on a 3-D model rather than lines on 2-D

  12. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Tanck, Esther; Deenen, J C W; Verdonschot, Nico [Orthopaedic Research Laboratory, Radboud University Nijmegen Medical Center, PO Box 9101, 6500 HB Nijmegen (Netherlands); Huisman, Henk Jan [Department of Radiology, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Kooloos, Jan G [Department of Anatomy, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands); Huizenga, Henk [Department of Radiotherapy, Radboud University Nijmegen Medical Center, Nijmegen (Netherlands)], E-mail: e.tanck@orthop.umcn.nl

    2010-01-21

    Bone specific, CT-based finite element (FE) analyses have great potential to accurately predict the fracture risk of deteriorated bones. However, it has been shown that differences exist between FE-models of femora scanned in a water basin or scanned in situ within the human body, as caused by differences in measured bone mineral densities (BMD). In this study we hypothesized that these differences can be reduced by re-creating the patient CT-conditions by using an anatomically shaped physical model of the lower body. BMD distributions were obtained from four different femora that were scanned under three conditions: (1) in situ within the cadaver body, (2) in a water basin and (3) in the body model. The BMD of the three scanning protocols were compared at two locations: proximally, in the trabecular bone of the femoral head, and in the cortical bone of the femoral shaft. Proximally, no significant differences in BMD were found between the in situ scans and the scans in the body model, whereas the densities from the water basin scans were on average 10.8% lower than in situ. In the femoral shaft the differences between the three scanning protocols were insignificant. In conclusion, the body model better approached the in situ situation than a water basin. Future studies can use this body model to mimic patient situations and to develop protocols to improve the performance of the FE-models in actual patients. (note)

  14. 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

  15. CT-scan bij stomp buiktrauma bij kinderen : veel stralen en weinig opbrengst?

    NARCIS (Netherlands)

    Nellensteijn, David R; El Moumni, Mostafa; Greuter, Marcel J W; Kneyber, Martin C J; Hulscher, Jan B F

    2013-01-01

    Blunt abdominal trauma in children occurs fairly frequently. Although computed tomography scanning is considered by many to be the gold standard, in children who are hemodynamically stable, CT images do not usually result in new perspectives that lead to changes in treatment management. However, the

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-10-01

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

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

    NARCIS (Netherlands)

    J.M. van der Zel

    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 sur

  18. Influence of cone beam CT scanning parameters on grey value measurements at an implant site

    NARCIS (Netherlands)

    Parsa, A.; Ibrahim, N.; Hassan, B.; Motroni, A.; van der Stelt, P.; Wismeijer, D.

    2013-01-01

    Objectives: The aim of this study was to determine the grey value variation at the implant site with different scan settings, including field of view (FOV), spatial resolution, number of projections, exposure time and dose selections in two cone beam CT (CBCT) systems and to compare the results with

  19. 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...

  20. 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...

  1. Do physical examination and CT-scan measures of femoral neck anteversion and tibial torsion relate to each other?

    Science.gov (United States)

    Sangeux, Morgan; Mahy, Jessica; Graham, H Kerr

    2014-01-01

    Informed clinical decision making for femoral and/or tibial de-rotation osteotomies requires accurate measurement of patient function through gait analysis and anatomy through physical examination of bony torsions. Validity of gait analysis has been extensively studied; however, controversy remains regarding the accuracy of physical examination measurements of femoral and tibial torsion. Comparison between CT-scans and physical examination measurements of femoral neck anteversion (FNA) and external tibial torsion (ETT) were retrospectively obtained for 98 (FNA) and 64 (ETT) patients who attended a tertiary hospital for instrumented gait analysis between 2007 and 2010. The physical examination methods studied for femoral neck anteversion were the trochanteric prominence angle test (TPAT) and the maximum hip rotation arc midpoint (Arc midpoint) and for external tibial torsion the transmalleolar axis (TMA). Results showed that all physical examination measurements statistically differed to the CT-scans (bias(standard deviation): -2(14) for TPAT, -10(12) for Arc midpoint and -16(9) for TMA). Bland and Altman plots showed that method disagreements increased with increasing bony torsions in all cases but notably for TPAT. Regression analysis showed that only TMA and CT-scan measurement of external tibial torsion demonstrated good (R(2)=57%) correlation. Correlations for both TPAT (R(2)=14%) and Arc midpoint (R(2)=39%) with CT-scan measurements of FNA were limited. We conclude that physical examination should be considered as screening techniques rather than definitive measurement methods for FNA and ETT. Further research is required to develop more accurate measurement methods to accompany instrumented gait analysis. Copyright © 2013. Published by Elsevier B.V.

  2. Extrapulmonary small cell sarcinoma: involvement of the brain without evidence of extracranial malignancy by serial PET/CT scans

    Directory of Open Access Journals (Sweden)

    Havlioglu Necat

    2008-09-01

    Full Text Available Abstract Background Extrapulmonary small cell carcinoma (EPSCC involving the brain is a rare manifestation of an uncommon tumor type. Case presentation We report a 59 year-old Caucasian female diagnosed with an EPSCC involving the left parietal lobe without detectable extracranial primary tumor followed by serial positron emission tomography/computed tomography (PET/CT imaging. Histopathological examination at both initial presentation and recurrence revealed small cell carcinoma. Serial PET/CT scans of the entire body failed to reveal any extracranial [18F]2-fluoro-2-deoxy-D-glucose (FDG avid lesions at either diagnosis or follow-up. Conclusion Chemotherapy may show a transient response in the treatment of EPSCC. Further studies are needed to help identify optimal treatment strategies. Combination PET/CT technology may be a useful tool to monitor EPSCC and assess for an occult primary malignancy.

  3. Autopsy case of acute multiple sclerosis with multifocal low density areas in the cerebral white matter on CT scans

    Energy Technology Data Exchange (ETDEWEB)

    Kamikura, Isao; Mizutani, Tomohiko; Sakamaki, Shuji; Takasu, Toshiaki; Kawamura, Toshiaki

    1988-01-01

    A 34-year-old woman presented with urination difficulty and consciousness disturbance, followed by persistent neurologic findings, such as semicomatose mental status and bilateral optic neuritis, and monophasic clinical course. Cranial CT showed multifocal low density areas in cerebral white matter. The patient was clinically diagnosed as having acute disseminated encephalomyelitis. She died of sepsis four months later. Autopsy revealed multifocal large demyelinating lesions confined to the cerebral white matter, shown as low density areas on CT scans, and demyelinating plaques scattered in the optic nerves and chiasm, and cerebral peduncle. The final diagnosis was acute multiple sclerosis. The CT appearance of multifocal low density areas was most likely due to demyelinating lesions causing edema and tissue necrosis. (Namekawa, K.).

  4. Correlation between the Degree and Severity of Symptoms and CT scan Changes in Chronic Rhinosinusitis (CRS

    Directory of Open Access Journals (Sweden)

    H. Moghaddasi

    2008-01-01

    Full Text Available Background/Objective: find out whether any correlation exists between the degree and severity of symptoms as assessed by the SNOT-20 questionnaire and CT scan changes as graded by Lund-Mackay scoring system in chronic rhinosinusitis (CRS."nPatients and Methods: Fifties patients attending the otolaryngology department and diagnosed with CRS were prospectively entered in this study. All patients had their CT scans graded by using the Lund-Mackay  with the sino-nasal outcome questionnaire (SNOT-20. Correlation analysis was conducted to determine whether the CT scan stage as assigned by Lund Mackay staging system correlated with the SNOT-20 scores."nResults: The mean age of our patients was 32.4±8.5 and 32(64% of them were male and 18(36% were female. The mean SNOT-20 was 45±8.7 (29-67 and the mean Lund-Mackay sinus score was 18.5±5 (8- 24.The mean SNOT-20 score was higher for postnasal drip (PND and facial pain, and the lowest mean scores were for dizziness and ear pain. The Pearson's correlation coefficient confirmed that there was a good correlation between SNOT-20 scores and CT scores (Pearson correlation coefficient 0.77; P value, 0.0001."nConclusion: Patients with higher symptom scores are more likely to have CT imaging evidence of rhinosinusitis. In patients with isolated sleep or systematic symptoms, the likelihood of rhinosinusitis is less, even if symptoms are severe. Therefore, in these patients, sinus CT-scan should be considered before treatment to establish the diagnosis of chronic rhinosinusitis due to that a number of these patients may be doing not have rhinosinusitis.

  5. Alternative oblique head CT scanning technique reduces bone artifact and improves interpretability of brainstem anatomy

    Directory of Open Access Journals (Sweden)

    Sam Douglas Kampondeni

    2010-06-01

    Full Text Available Brainstem pathology due to infections, infarcts and tumors are common in developing countries, but neuroimaging technology in these resource-poor settings is often limited to single slice, and occasionally spiral, CT. Unlike multislice CT and MRI, single slice and spiral CT are compromised by bone artifacts in the posterior fossa due to the dense petrous bones, often making imaging of the brainstem non-diagnostic. With appropriate head positioning, the petrous ridges can be avoided with 40˚ sagittal oblique scans parallel to either petrous ridge. We describe an alternative sagittal oblique scanning technique that significantly reduces brainstem CT artifacts thereby improving clarity of anatomy. With Inst­itutional Ethical approval, 13 adult patients were enrolled (5 males; 39%. All patients had routine axial brain CT and sagittal oblique scans with no lesions found. Images were read by 2 readers who gave a score for amount of artefact and clarity of structures in the posterior fossa. The mean artifact score was higher for routine axial images compared to sagittal oblique (2.92 vs. 1.23; P<0.0001. The mean anatomical certainty scores for the brainstem were significantly better in the sagittal oblique views compared to routine axial (1.23 vs. 2.77; P<0.0001. No difference was found between the two techniques with respect to the fourth ventricle or the cerebellum (axial vs. sag oblique: 1.15 vs. 1.27; P=0.37. When using single slice CT, the sagittal oblique scanning technique is valuable in improving clarity of anatomy in the brainstem if axial images are non-diagnostic due to bone artifacts.

  6. Low-dose adaptive sequential scan for dual-source CT coronary angiography in patients with high heart rate: Comparison with retrospective ECG gating

    Energy Technology Data Exchange (ETDEWEB)

    Xu Lei, E-mail: leixu2001@hotmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Yang Lin, E-mail: anna7949@163.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Zhang Zhaoqi, E-mail: zhaoqi5000@vip.sohu.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Li Yu, E-mail: athen06@hotmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Fan Zhanming, E-mail: fanzm120@tom.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Ma Xiaohai, E-mail: maxi8238@gmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Lv Biao, E-mail: biao_lu2007@sina.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China); Yu Wei, E-mail: yuwei02@gmail.com [Department of Radiology, Beijing Anzhen Hospital, Capital Medical University, 100029 Beijing (China)

    2010-11-15

    Purpose: To explore feasibility of dual-source CT (DS-CT) prospective ECG-gated coronary angiography in patients with heart rate (HR) higher than 70 beat per minute (bpm), and evaluate image quality and radiation dose with comparison to retrospective ECG-gated spiral scan. Materials and methods: One hundred patients who underwent DS-CT coronary angiography (DS-CTCA) with mean HR higher than 70 bpm but below 110 bpm were enrolled in the study, 50 were scanned by adaptive sequential scan and another 50 were analyzed by retrospectively gated CT scan. The imaging quality of coronary artery segments in the two groups was evaluated using a four-point grading scale by two independent reviewers. Patient radiation dose was calculated by multiplying dose length product by conversion coefficient of 0.017. Results: There was no significant difference between the two groups for mean HR (p = 0.305), HR variability (p = 0.103), body mass index (p = 0.472), and scan length (p = 0.208). There was good agreement for image quality scoring between the two reviewers (Kappa = 0.72). Coronary evaluability of adaptive sequential scan was 99.7% (608 of 610 segments), while that of retrospective gated scan was 98.7% (614 of 622 segments), showing similar coronary evaluability (p = 0.061). Effective doses of adaptive sequential scan and retrospective gated scan were 5.1 {+-} 1.6 and 11.8 {+-} 4.5 mSv, respectively (p < 0.001), showing that adaptive sequential scan reduced radiation dose by 57% compared with that of retrospective gated scan. Conclusions: In patients with 70-110 bpm HR, DS-CTCA adaptive sequential scan shows similar image quality as retrospective ECG-gated spiral scan with 57% reduction of radiation dose.

  7. Value and clinical application of orthopedic metal artifact reduction algorithm in CT scans after orthopedic metal implantation

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Yi; Pan, Shinong; Zhao, Xudong; Guo, Wenli; He, Ming; Guo, Qiyong [Shengjing Hospital of China Medical University, Shenyang (China)

    2017-06-15

    To evaluate orthopedic metal artifact reduction algorithm (O-MAR) in CT orthopedic metal artifact reduction at different tube voltages, identify an appropriate low tube voltage for clinical practice, and investigate its clinical application. The institutional ethical committee approved all the animal procedures. A stainless-steel plate and four screws were implanted into the femurs of three Japanese white rabbits. Preoperative CT was performed at 120 kVp without O-MAR reconstruction, and postoperative CT was performed at 80–140 kVp with O-MAR. Muscular CT attenuation, artifact index (AI) and signal-to-noise ratio (SNR) were compared between preoperative and postoperative images (unpaired t test), between paired O-MAR and non-O-MAR images (paired Student t test) and among different kVp settings (repeated measures ANOVA). Artifacts' severity, muscular homogeneity, visibility of inter-muscular space and definition of bony structures were subjectively evaluated and compared (Wilcoxon rank-sum test). In the clinical study, 20 patients undertook CT scan at low kVp with O-MAR with informed consent. The diagnostic satisfaction of clinical images was subjectively assessed. Animal experiments showed that the use of O-MAR resulted in accurate CT attenuation, lower AI, better SNR, and higher subjective scores (p < 0.010) at all tube voltages. O-MAR images at 100 kVp had almost the same AI and SNR as non-O-MAR images at 140 kVp. All O-MAR images were scored ≥ 3. In addition, 95% of clinical CT images performed at 100 kVp were considered satisfactory. O-MAR can effectively reduce orthopedic metal artifacts at different tube voltages, and facilitates low-tube-voltage CT for patients with orthopedic metal implants.

  8. Acute Pyelonephritis Focusing on Perfusion Defects on Contrast Enhansed Computerized Tomography(CT) Scans and Its Clinical Outcome

    Science.gov (United States)

    Ha, Sung-Kyu; Seo, Jung-Kun; Kim, Seung-Jung; Park, Seung-Ho; Park, Chong-Hoon; Lee, Ho-Yung; Han, Dae-Suk; Kim, Ki-Whang

    1997-01-01

    Objectives Many cases of acute pyelonephritis show renal perfusion defects on contrast enhanced computerized tomography (CT) imaging studies. The purpose of this study is to show the frequency of renal perfusion defects in uncomplicated acute pyelonephritis and to compare the clinical responses of patients who had perfusion defects or not. Methods We studied patients who had symptoms and signs of acute pyelonephritis through CT examinations with contrast enhancement. We identified 21 cases who had perfusion defects among 35 patients who had undergone CT imaging studies and compared the clinical data in the two groups of patients who had perfusion defects on CT (group 1) and who had not (group 2). Results Nearly all patients had typical symptoms and signs of acute pyelonephritis such as high fever and chill, flank pain and costovertebral angle tenderness. Combined clinical problems were septic shock (one case, 4.8%) and disseminated intravascular coagulation (DIC) (one case, 4.8%) in group 1. Laboratory findings were not different between the two groups. All patients were treated with antibiotics and had successful recoveries. The duration of recovery of pyuria in group 1 (5.2±9.6 days) was not longer than that in group 2(3.1±2.9 days) (p>0.05). The length of defeverscence in group 1 (7.0±4.6 days) was longer than in group 2 (3.5±2.7 days) (ppyelonephritis patients). We classified CT findings of group 1 as focal unilateral (2 cases, 9.5%), multifocal unilateral (14 cases, 66.7%) and multifocal bilateral (5 cases, 23.8%), and there were no differences between the subgroups of group 1 in the duration of defeverscence. Conclusion Those patients who had perfusion defects on CT showed relatively severe clinical courses but responses to early antibiotics were very good. Contrast enhanced CT scans may be very sensitive for the detection of acute renal parenchymal inflammatory disease and for defining the extent of disease, but it is clinically not essential to perform

  9. Value of Bone Scan in Addition to F-18 FDG PET/CT and Characteristics of Discordant Lesions between F-18 FDG PET/CT and Bone Scan in the Spinal Bony Metastasis

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Sung Min; Nam, Hyun Yeol; Kim, In Ju; Kim, Yong Ki [Pusan National University Hospital, Pusan (Korea, Republic of); Kim, Ju Sung [College of Medical Life Science, Silla University, Pusan (Korea, Republic of)

    2008-06-15

    Our purpose was to evaluate spinal bony metastasis which could be missed on an F-18 FDG PET/CT (FDG PET/CT) alone, and to characterize discordant metastatic lesions between FDG PET/CT and bone scan. FDG PET/CT and bone scans of 43 patients with spinal bony metastasis were analyzed retrospectively. A McNemar test was performed comparing the FDG PET/CT alone to the FDG PET/CT plus bone scan in the spinal bony metastases. A one-way chi-square test was performed to characterize the metastases that were missed on the FDG PET/CT alone. To evaluate discordant lesions between FDG PET/CT and bone scan, we performed logistic regression analyses. The independent variables were sites (cervical, thoracic, and lumbar), size (large and small), and maximum SUVs, and the dependant variable was bone scan uptake (positive and negative MDP uptake). A significant difference was found between the FDG PET/CT alone and the FDG PET/CT combined with the bone scan (p<0.01). Using the FDG PET/CT only, diffuse osteoblastic metastasis was missed with a significantly higher frequency (p=0.04). In the univariate analysis, cervical vertebra and small size were related to negative MDP uptake, and thoracic vertebra and large size were related to positive MDP uptake. However, in the multivariate analysis, only the large size was related to positive MDP uptake. A bone scan in addition to the FDG PET/CT increased the ability to evaluate spinal bony metastases, especially for diffuse osteoblastic metastasis. Large metastasis was related to positive bone scan uptake in spinal bony metastasis.

  10. Contrast enhancement characteristics of hepatocellular carcinoma on two-phase dynamic scan with spiral CT

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Dae Young; Choi, Byung Ihn; Han, Joon Koo; Han, Man Chung [College of Medicine, Seoul National University, Seoul (Korea, Republic of)

    1994-12-15

    The purpose of this study was to characterize the enhancing patterns of hepatocellular carcinoma (HCC) on two-phase dynamic incremental liver scan with spiral CT. Two-phase dynamic incremental liver scan using spiral CT was performed on 230 lesions in 107 patients with HCC. CT scanning was performed with a table speed of 13 mm/sec and a section thickness of 10 mm; 120 mL of contrast medium was injected intravenously with a automatic injector at the rate of 3 mL/sec. CT scans were started 35 sec(early phase) and 3 min(delayed phase) after beginning injection of contrast medium. The tumors were divided into 2 groups according to size({<=}3cm and > 3cm), the contrast enhancement patterns of HCCs and capsules in the early and delayed phases were analyzed in each group. Most of HCCs appeared as high-attenuating lesions in the early phase(75% in tumors smaller than 3cm and 61 % in tumors larger than 3cm), and as low-attenuating lesions in the delayed phase(68% in tumors smaller than 3cm and 90% in tumors larger than 3cm). Forty-eight percent of HCCs smaller than 3cm and 58% of HCCs larger than 3 cm were high-attenuating in the early phase and low-attenuating in the delayed phase. Thirty-two percent of capsules were low- or iso-attenuating in the early phase and high-attenuating in the delayed phase. Capsules were demonstrated in 22% in HCCs smaller than 3cm and 67% in HCCs larger than 3 cm (p <. 01). Two-phase dynamic scan with spiral CT is useful in the diagnosis of HCC because of a precise display of hemodynamic characteristics of HCCs.

  11. Analysis of chromosome translocation frequency after a single CT scan in adults.

    Science.gov (United States)

    Abe, Yu; Miura, Tomisato; Yoshida, Mitsuaki A; Ujiie, Risa; Kurosu, Yumiko; Kato, Nagisa; Katafuchi, Atsushi; Tsuyama, Naohiro; Kawamura, Fumihiko; Ohba, Takashi; Inamasu, Tomoko; Shishido, Fumio; Noji, Hideyoshi; Ogawa, Kazuei; Yokouchi, Hiroshi; Kanazawa, Kenya; Ishida, Takashi; Muto, Satoshi; Ohsugi, Jun; Suzuki, Hiroyuki; Ishikawa, Tetsuo; Kamiya, Kenji; Sakai, Akira

    2016-06-01

    We recently reported an increase in dicentric chromosome (DIC) formation after a single computed tomography (CT) scan (5.78-60.27 mSv: mean 24.24 mSv) and we recommended analysis of 2000 metaphase cells stained with Giemsa and centromere-FISH for dicentric chromosome assay (DCA) in cases of low-dose radiation exposure. In the present study, we analyzed the frequency of chromosome translocations using stored Carnoy's-fixed lymphocyte specimens from the previous study; these specimens were from 12 patients who were subject to chromosome painting of Chromosomes 1, 2 and 4. Chromosomes 1, 2 and 4 were analyzed in ∼5000 cells, which is equivalent to the whole-genome analysis of almost 2000 cells. The frequency of chromosome translocation was higher than the number of DICs formed, both before and after CT scanning. The frequency of chromosome translocations tended to be higher, but not significantly higher, in patients with a treatment history compared with patients without such a history. However, in contrast to the results for DIC formation, the frequency of translocations detected before and after the CT scan did not differ significantly. Therefore, analysis of chromosome translocation may not be a suitable assay for detecting chromosome aberrations in cases of low-dose radiation exposure from a CT scan. A significant increase in the frequency of chromosome translocations was not likely to be detected due to the high baseline before the CT scan; the high and variable frequency of translocations was probably due to multiple confounding factors in adults.

  12. Thromboembolic Complications Following Spine Surgery Assessed with Spiral CT Scans: DVT/PE Following Spine Surgery.

    Science.gov (United States)

    Kim, Han Jo; Walcott-Sapp, Sarah; Adler, Ronald S; Pavlov, Helene; Boachie-Adjei, Oheneba; Westrich, Geoffrey H

    2011-02-01

    Spine surgery is associated with a significant risk of postoperative pulmonary embolism (PE) and/or deep vein thrombosis (DVT). The goal of this study was to determine which symptoms and risk factors were associated with spiral CT scans positive for PE and/or DVT in the postoperative spine surgery patient. We conducted a retrospective review of all spine patients who underwent a postoperative CT to rule out PE during the period of March 2004-February 2006. The type of surgical procedure, risk factors, symptoms prompting scan ordering, anticoagulation, and treatment were recorded. Logistic regression models were used to determine significant predictors of a positive CT in this patient population. Of the 3,331 patients that had spine surgery during the study period, 130 (3.9%) had a spiral CT scan to rule out PE and/or proximal DVT. Thirty-three of the 130 (25.4%) CT scans were positive for PE only, five (3.8%) for PE and DVT, and three (2.3%) for DVT only. Only 24.5% (32) patients had risk factors for thromboembolic disease, and of these, a history of PE and/or DVT was the only significant risk factor for a positive scan (p = 0.03). No presenting symptoms or demographic variables were noted to have a significant association with PE and/or DVT. The type of surgical procedure (i.e., anterior, posterior, and percutaneous) was not associated with an increased risk for PE and/or DVT. Patients who are undergoing spine surgery with a history of thromboembolic disease should be carefully monitored postoperatively and may benefit from more aggressive prophylaxis.

  13. Hepatic scar in a case of healed candidiasis showing prolonged enhancement on CT

    Energy Technology Data Exchange (ETDEWEB)

    Itai, Yuji; Yashiro, Naobumi

    1987-08-01

    A patient with acute myelocytic leukemia recovering from hepatic candidiasis after long-term administration of amphotericin B had large scar in the liver which showed prominent prolonged enhancement on postcontrast CT. Prolonged enhancement can occur in regions other than hepatic masses.

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

    Institute of Scientific and Technical Information of China (English)

    Jiang-Xia Lei

    2016-01-01

    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 andsurvivin in pancreatic cancer tissue samples were higher than those in para-carcinoma tissue samples, and mRNA expression levels ofP53 andBax 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 ofBcl-2, Bcl-xL and survivinin pancreatic cancer tissue, and positively correlated with mRNA expression levels ofP53andBaxin 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 positive role in guiding clinical

  15. Advanced material separation technique based on dual energy CT scanning

    Science.gov (United States)

    Zamyatin, Alexander A.; Natarajan, Anusha; Zou, Yu

    2009-02-01

    We propose a method for material separation using dual energy data. Our method is suitable to separation of three or more materials. In this work we describe our method and show results of numerical simulation and with real dual-energy data of a head phantom. The proposed method of constructing the material separation map consists of the following steps: Data-domain dual energy decomposition - Vector plot - Density plot - Clustering - Color assignment. Density plots are introduced to allow automatic cluster separation. We use special image processing methods, including Gaussian decomposition, to improve the accuracy of material separation. We also propose using the HSL color model for better visualization and to bring a new dimension in material separation display. We study applications of bone removal and virtual contrast removal. Evaluation shows improved accuracy compared to standard methods.

  16. CT Diagnosis of Fitz-Hugh and Curtis Syndrome: Value of the Arterial Phase Scan

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Seung Ho; Kim, Myeong Jin; Lim, Joon Seok; Kim, Joo Hee; Kim, Ki Whang [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2007-02-15

    We wanted to evaluate the role of the arterial phase (AP) together with the portal venous phase (PP) scans in the diagnosis of Fitz-Hugh-Curtis syndrome (FHCS) with using computed tomography (CT). Twenty-five patients with FHCS and 25 women presenting with non-specifically diagnosed acute abdominal pain and who underwent biphasic CT examinations were evaluated. The AP scan included the upper abdomen, and the PP scan included the whole abdomen. Two radiologists blindly and retrospectively reviewed the PP scans first and then they reviewed the AP plus PP scans. The diagnostic accuracy of FHCS on each image set was compared for each reader by analyzing the area under the receiver operating characteristic curve (Az). Weighted kappa (wk) statistics were used to measure the interobserver agreement for the presence of CT signs of the pelvic inflammatory disease (PID) on the PP images and FHCS as the diagnosis based on the increased perihepatic enhancement on both sets of images. The individual diagnostic accuracy of FHCS was higher on the biphasic images (Az = 0.905 and 0.942 for reader 1 and 2, respectively) than on the PP images alone (Az = 0.806 and 0.706, respectively). The interobserver agreement for the presence of PID on the PP images was moderate (wk = 0.530). The interobserver agreement for FHCS as the diagnosis was moderate on only the PP images (wk = 0.413), but it was substantial on the biphasic images (wk 0.719). Inclusion of the AP scan is helpful to depict the increased perihepatic enhancement, and it improves the diagnostic accuracy of FHCS on CT.

  17. Effect of Scanning and Reconstruction Parameters on Three Dimensional Volume and CT Value Measurement of Pulmonary Nodules: A Phantom Study

    Directory of Open Access Journals (Sweden)

    Datong SU

    2017-08-01

    Full Text Available Background and objective The computed tomography (CT follow-up of indeterminate pulmonary nodules aiming to evaluate the change of the volume and CT value is the common strategy in clinic. The CT dose needs to considered on serious CT scans in addition to the measurement accuracy. The purpose of this study is to quantify the precision of pulmonary nodule volumetric measurement and CT value measurement with various tube currents and reconstruction algorithms in a phantom study with dual-energy CT. Methods A chest phantom containing 9 artificial spherical solid nodules with known diameter (D=2.5 mm, 5 mm, 10 mm and density (-100 HU, 60 HU and 100 HU was scanned using a 64-row detector CT canner at 120 Kilovolt & various currents (10 mA, 20 mA, 50 mA, 80 mA,100 mA, 150 mA and 350 mA. Raw data were reconstructed with filtered back projection and three levels of adaptive statistical iterative reconstruction algorithm (FBP, ASIR; 30%, 50% and 80%. Automatic volumetric measurements were performed using commercially available software. The relative volume error (RVE and the absolute attenuation error (AAE between the software measures and the reference-standard were calculated. Analyses of the variance were performed to evaluate the effect of reconstruction methods, different scan parameters, nodule size and attenuation on the RPE. Results The software substantially overestimated the very small (D=2.5 mm nodule's volume [mean RVE: (100.8%±28%] and underestimated it attenuation [mean AAE: (-756±80 HU]. The mean RVEs of nodule with diameter as 5 mm and 10 mm were small [(-0.9%±1.1% vs (0.9%±1.4%], however, the mean AAEs [(-243±26 HU vs (-129±7 HU] were large. The ANOVA analysis for repeated measurements showed that different tube current and reconstruction algorithm had no significant effect on the volumetric measurements for nodules with diameter of 5 mm and 10 mm (F=5.60, P=0.10 vs F=11.13, P=0.08, but significant effects on the measurement of CT

  18. 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.

  19. 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).

  20. Repositioning accuracy of cerebral fractionated stereotactic radiotherapy using CT scanning; Evaluation par tomodensitometrie du repositionnement en radiotherapie stereotaxique fractionnee cerebrale

    Energy Technology Data Exchange (ETDEWEB)

    Pasquier, D.; Dubus, F.; Castelain, B.; Delplanque, M.; Lartigau, E. [Centre O.-Lambret, Dept. Universitaire de Radiotherapie, 59 - Lille (France); Pasquier, D. [Centre Galilee, Polyclinique de la Louviere, 59 - Lille (France); Bernier, V.; Buchheit, I. [Centre Alexis-Vautrin, Dept. de Radiotherapie, 54 - Vandoeuvre-les-Nancy (France); Kerr, C.; Santoro, I. [Centre Val d' Aurelle, Dept. de Radiotherapie, 34 - Montpellier (France); Huchet, A.; Causse, N. [Hopital Saint-Andre, Dept. de Radiotherapie, 33 - Bordeaux (France); Dubus, F.; Castelain, B.; Delplanque, M.; Lartigau, E. [Lille-2 Univ., 59 (France)

    2009-09-15

    Purpose: To evaluate the accuracy of patient repositioning in fractionated cerebral stereotactic radiotherapy using a Brain Lab stereotactic cranial mask in conjunction with standard dental fixation. Patients and methods: Fifty planning and checking CT scans were performed in 25 patients. The check CT scan was performed before or after one of the three sessions of treatment. Co registration to the planning CT scan was used to assess alignment of the iso centre to the reference markers. The relative position of the P.T.V. with regard to iso centre allowed us to determine its total displacement (3-dimensional vector). Results: Mean iso centre translations ({+-} S.D.) taking into account direction were -0.01 {+-} 0.7, -0.2 {+-} 1.3 and 0.07 {+-} 0.5 mm in medio-lateral, cranio caudal and anteroposterior directions respectively. Mean rotations ({+-}S.D.) were -0.02 {+-} 0.6, -0.08 {+-} 0.3 and -0.1 {+-} 0.3 degree in medio-lateral, cranio caudal and anteroposterior axes respectively. Mean overall P.T.V. displacement was 1.8 {+-} 1.5 mm. P.T.V. displacement was smaller than 2 and 3 mm in 19/25 and 23/25 patients respectively. Conclusion: The accuracy of patient positioning using a stereotactic cranial mask system is similar to those reported in the literature and shows a satisfactory reproducibility with a standard dental fixation. (authors)

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

    Science.gov (United States)

    Marquet, F.; Pernot, M.; Aubry, J.-F.; Montaldo, G.; Marsac, L.; Tanter, M.; Fink, M.

    2009-05-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-05-07

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

  3. Influence of cone beam CT scanning parameters on grey value measurements at an implant site.

    Science.gov (United States)

    Parsa, A; Ibrahim, N; Hassan, B; Motroni, A; van der Stelt, P; Wismeijer, D

    2013-01-01

    The aim of this study was to determine the grey value variation at the implant site with different scan settings, including field of view (FOV), spatial resolution, number of projections, exposure time and dose selections in two cone beam CT (CBCT) systems and to compare the results with those obtained from a multislice CT system. A partially edentulous human mandibular cadaver was scanned by three CT modalities: multislice CT (MSCT) (Philips, Best, the Netherlands), and two CBCT systems: (Accuitomo 170(®), Morita, Japan) and (NewTom 5G(®), QR, Verona, Italy). Using different scan settings 36 and 24 scans were obtained from the Accuitomo and the NewTom, respectively. The scans were converted to digital imaging and communications in medicine 3 format. The analysis of the data was performed using 3Diagnosys(®) software (v. 3.1, 3diemme, Cantù, Italy) and Geomagic studio(®) 2012 (Morrisville, NC). On the MSCT scan, one probe designating the site for pre-operative implant placement was inserted. The inserted probe on MSCT was transformed to the same region on each CBCT scan using a volume-based three-dimensional registration algorithm. The mean voxel grey value of the region around the probe was derived separately for each CBCT. The influence of scanning parameters on the measured mean voxel grey values was assessed. Grey values in both CBCT systems significantly deviated from Hounsfield unit values measured with MSCT (p = 0.0001). In both CBCT systems, scan FOV and spatial resolution selections had a statistically significant influence on grey value measurements (p = 0.0001). The number of projections selection had a statistically significant influence in the Accuitomo system (p = 0.0001) while exposure time and dose selections had no statistically significant influence on grey value measurements in the NewTom (p = 0.43 and p = 0.37, respectively). Grey-level values from CBCT images are influenced by device and scanning settings.

  4. Optimization of megavoltage CT scan registration settings for brain cancer treatments on tomotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Woodford, Curtis; Yartsev, Slav; Van Dyk, Jake [London Regional Cancer Program, London Health Sciences Centre, 790 Commissioners Road East, London, Ontario (Canada)

    2007-04-21

    This study aims to determine the settings that provide the optimal clinical accuracy and consistency for the registration of megavoltage CT (MVCT) with planning kilovoltage CT image sets on the Hi-ART tomotherapy system. The systematic offset between the MVCT and the planning kVCT was determined by registration of multiple MVCT scans of a head phantom aligned with the planning isocentre. Residual error vector lengths and components were used to quantify the alignment quality for the phantom shifted by 5 mm in different directions obtained by all 27 possible combinations of MVCT inter-slice spacing, registration techniques and resolution. MVCT scans with normal slices are superior to coarse slices for registration of shifts in the superior-inferior, lateral and anterior-posterior directions. Decreasing the scan length has no detrimental effect on registration accuracy as long as the scan lengths are larger than 24 mm. In the case of bone technique and fine resolution, normal and fine MVCT scan slice spacing options give similar accuracy, so normal mode is preferable due to shorter procedure and less delivered dose required for patient set-up. A superior-inferior field length of 24-30 mm, normal slice spacing, bone technique, and fine resolution is the optimum set of registration settings for MVCT scans of a Rando head phantom acquired with the Hi-ART tomotherapy system, provided the registration shifts are less than 5 mm. (note)

  5. 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)

  6. 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.

  7. Quantification of radiation-induced lung damage with CT scans - The possible benefit for radiogenomics

    Energy Technology Data Exchange (ETDEWEB)

    De Ruysscher, Dirk [Radiation Oncology, Univ. Hospitals Leuven/KU Leuven, Leuven (Belgium); Dept. of Radiation Oncology (Maastro clinic), Maastricht Univ. Medical Center, Maastricht (Netherlands)], e-mail: dirk.deruysscher@uzleuven.be; Sharifi, Hoda [Dept. of Radiation Oncology (Maastro clinic), Maastricht Univ. Medical Center, Maastricht (Netherlands); Defraene, Gilles [Radiation Oncology, Univ. Hospitals Leuven/KU Leuven, Leuven (Belgium)] [and others

    2013-10-15

    Background: Radiation-induced lung damage (RILD) is an important problem. Although physical parameters such as the mean lung dose are used in clinical practice, they are not suited for individualised radiotherapy. Objective, quantitative measurements of RILD on a continuous instead of on an ordinal, semi-quantitative, semi-subjective scale, are needed. Methods: Hounsfield unit (HU) changes before versus three months post-radiotherapy were correlated per voxel with the radiotherapy dose in 95 lung cancer patients. Deformable registration was used to register pre- and post-CT scans and the density increase was quantified for various dose bins. The dose-response curve for increased HU was quantified using the slope of a linear regression (HU/Gy). The end-point for the toxicity analysis was dyspnoea = grade 2. Results: Radiation dose was linearly correlated with the change in HU (mean R2 = 0.74 {+-} 0.28). No differences in HU/Gy between groups treated with stereotactic radiotherapy, conventional radiotherapy alone, sequential or concurrent chemo-radiotherapy were observed. In the whole patient group, 33/95 (34.7%) had dyspnoea {>=} G2. Of the 48 patients with a HU/Gy below the median, 16 (33.3%) developed dyspnoea = G2, while in the 47 patients with a HU/Gy above the median, 17 (36.1%) had dyspnoea {>=}G2 (not significant). Individual patients showed a nearly 21-fold difference in radiosensitivity, with HU/Gy ranging from 0 to 10 HU/Gy. Conclusions: HU changes identify objectively the whole range of individual radiosensitivity on a continuous, quantitative scale. CT density changes may allow more robust and accurate radiogenomics studies.

  8. Automatic transperineal ultrasound probe positioning based on CT scan for image guided radiotherapy

    Science.gov (United States)

    Camps, S. M.; Verhaegen, F.; Paiva Fonesca, G.; de With, P. H. N.; Fontanarosa, D.

    2017-03-01

    Image interpretation is crucial during ultrasound image acquisition. A skilled operator is typically needed to verify if the correct anatomical structures are all visualized and with sufficient quality. The need for this operator is one of the major reasons why presently ultrasound is not widely used in radiotherapy workflows. To solve this issue, we introduce an algorithm that uses anatomical information derived from a CT scan to automatically provide the operator with a patient-specific ultrasound probe setup. The first application we investigated, for its relevance to radiotherapy, is 4D transperineal ultrasound image acquisition for prostate cancer patients. As initial test, the algorithm was applied on a CIRS multi-modality pelvic phantom. Probe setups were calculated in order to allow visualization of the prostate and adjacent edges of bladder and rectum, as clinically required. Five of the proposed setups were reproduced using a precision robotic arm and ultrasound volumes were acquired. A gel-filled probe cover was used to ensure proper acoustic coupling, while taking into account possible tilted positions of the probe with respect to the flat phantom surface. Visual inspection of the acquired volumes revealed that clinical requirements were fulfilled. Preliminary quantitative evaluation was also performed. The mean absolute distance (MAD) was calculated between actual anatomical structure positions and positions predicted by the CT-based algorithm. This resulted in a MAD of (2.8±0.4) mm for prostate, (2.5±0.6) mm for bladder and (2.8±0.6) mm for rectum. These results show that no significant systematic errors due to e.g. probe misplacement were introduced.

  9. Leptomeningeal angiomatosis of the left occipital surface detected by CT scan. With special reference to Sturge-Weber disease

    Energy Technology Data Exchange (ETDEWEB)

    Niiro, Masaki; Mihara, Tadahiro; Maeda, Yoshiki; Awa, Hiroshi; Kadota, Koki; Asakura, Tetsuhiko (Kagoshima Univ. (Japan). Faculty of Medicine)

    1982-10-01

    A case of left occipital leptomeningeal angiomatosis was reported. The patient was a 12-year-old boy who had episodes of severe vascular type headache accompanied by transient right homonymous hemianopsia. CT scan showed localized superficial high density area in the left occipital pole. Remarkable enhancement of the lower and inner surface of the left occipital lobe was demonstrated. Angiography showed poor filling of the distal portion of the left posterior cerebral artery. Skull tomograms showed linear calcifications in the left occipital region. Brain scan showed increased RI uptake in the left occipital region. During operation, the surface of the left occipital lobe was covered by excessive, fine, vascular networks which extended over the arachnoid membrane. The abnormal vessels were cauterized by a CO/sub 2/ laser as throughly as possible. The occipital pole felt gritty. Histologically, the abnormal vessels had spread into the subarachnoid space and were predominantly veins with thin and enlarged walls. The abnormal vessels followed the leptomeninges in the sulci of the cerebral cortex. Underneath the abnormal vessels, in the external layers of the cerebral cortex, calcium deposits were scattered and gliosis and degeneration of the ganglion cells were observed. The lesion was comparable with leptomeningeal angiomatosis. Though the pathological findings of the specimen, CT findings, and brain scan findings were extremely similar to those of Sturge-Weber disease, in this case, the typical clinical and roentgenographic findings of Sturge-Weber disease were all absent.

  10. Utility of 18 F-FDG PET/CT scan to diagnose the etiology of fever of unknown origin in patients on dialysis.

    Science.gov (United States)

    Tek Chand, Kalawat; Chennu, Krishna Kishore; Amancharla Yadagiri, Lakshmi; Manthri Gupta, Ranadheer; Rapur, Ram; Vishnubotla, Siva Kumar

    2017-04-01

    Studies on fever of unknown origin (FUO) in patients of chronic kidney disease and end stage renal disease patients on dialysis were not many. In this study, we used 18 F-FDG PET/CT scan whole body survey for detection of hidden infection, in patients on dialysis, labelled as FUO. In this retrospective study, 20 patients of end stage renal disease on dialysis were investigated for the cause of FUO using 18F-FDG PET/CT scan. All these patients satisfied the definition of FUO as defined by Petersdorf and Beeson. Any focal abnormal site of increased FDG concentration detected by PET/CT, either a solitary or multiple lesions was documented and at least one of the detected abnormal sites of radio tracer concentration was further examined for histopathology. All patients were on renal replacement therapy. Of these, 18 were on hemodialysis and two were on peritoneal dialysis. 18F-FDG PET/CT scan showed metabolically active lesions in 15 patients and metabolically quiescent in five patients. After 18F-FDG PET/CT scan all, but one patient had a change in treatment for fever. Anti-tuberculous treatment was given in 15 patients, antibiotics in four patients and anti-malaria treatment in one patient. The present study is first study of 18F-FDG PET/CT scan in patients of end stage renal disease on dialysis with FUO. The study showed that the 18 F FDG PET/CT scan may present an opportunity to attain the diagnosis in end stage renal disease patients on dialysis with FUO. © 2016 International Society for Hemodialysis.

  11. The prognostic value of brain CT scan in infants with periventricular leukomalacia

    Energy Technology Data Exchange (ETDEWEB)

    Okumura, Akihisa; Hayakawa, Fumio; Kuno, Kuniyoshi (Anjo Kosei Hospital, Aichi (Japan)); Natsume, Jun; Watanabe, Kazuyoshi

    1994-11-01

    Brain CT scan was performed at 40 weeks of conceptional age in 17 preterm infants with periventricular leukomalacia (PVL). The finding of periventricular low density was not useful in differentiating patients with PVL from normal infants, because this finding was seen in 40% of normal infants. The following findings were characteristic of PVL : (1) a marked low density area in centrum semioval, (2) an irregular outline of ventricular wall, and (3) low density spots in periventricular white matter. The findings of ventricular dilation with irregular wall and marked low density area in centrum semioval were correlated with a finding of volume loss on MRI during late infancy and the severity of neurological impairment, especially in severely affected patients. Marked low density area in centrum semioval was characteristic of severe PVL as demonstrated on brain CT scan. (author).

  12. SEGMENTATION OF CT SCAN LUMBAR SPINE IMAGE USING MEDIAN FILTER AND CANNY EDGE DETECTION ALGORITHM

    Directory of Open Access Journals (Sweden)

    E.Punarselvam

    2013-09-01

    Full Text Available The lumbar vertebrae are the largest segments of the movable part of the vertebral column, they are elected L1 to L5, starting at the top. The spinal column, more commonly called the backbone, is made up primarily of vertebrae discs, and the spinal cord. Acting as a communication conduit for the brain, signals are transmitted and received through the spinal cord. It is otherwise known as vertebralcolumn consists of 24 separate bony vertebrae together with 5 fused vertebrae, it is the unique interaction between the solid and fluid components that provides the disc strength and flexibility required to bear loading of the lumbar spine. In this work the Segmentation of Spine Image using Median Filter and Canny Edge Detection Algorithm between lumbar spine CT scan spine disc image. The result shows thatthe canny edge detection algorithm produced better result when compared other edge detection algorithm. Finding the correct boundary in a noisy image of spine disc is still a difficult one. To find outabsolute edges from noisy images, the comparative result can be verified and validated with the standard medical values. The result shows that the canny edge detection algorithm performs well and produced a solution very nearer to the optimal solution. This method is vigorous for all kinds of noisy images.

  13. Cystic Fibrosis: Are Volumetric Ultra-Low-Dose Expiratory CT Scans Sufficient for Monitoring Related Lung Disease?

    DEFF Research Database (Denmark)

    Loeve, Martine; Lequin, Maarten H; Bruijne, Marleen de

    2009-01-01

    that differences in scores were independent of score magnitude. Conclusion: In this pilot study, CT scores from end-expiratory and end-inspiratory CT match closely, suggesting that ultra-low-dose end-expiratory CT alone may be sufficient for monitoring CF-related lung disease. This would help reduce radiation dose......Purpose: To assess whether chest computed tomography (CT) scores from ultra-low-dose end-expiratory scans alone could suffice for assessment of all cystic fibrosis (CF)-related structural lung abnormalities. Materials and Methods: In this institutional review board–approved study, 20 patients...... 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...

  14. 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.

  15. 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.

  16. 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.

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

    Energy Technology Data Exchange (ETDEWEB)

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

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

  18. Anatomical basis for the interpretation of CT-scan imaging of the lumbar spine. Pitfalls

    Energy Technology Data Exchange (ETDEWEB)

    Laredo, J.D.; Bard, M.

    1988-01-01

    A good understanding of the normal anatomy of the lumbar spine is required for the interpretation of CT-scans obtained for ischiatic or crural neuralgia. An attempt has been made to rely on precise terminology to designate each anatomical region pertaining to the lumbar canal. Examples of tomodensitometric investigations of the normal intervertebral space are given, and criteria allowing for the identification of normal anatomical variations are also provided.

  19. Thoracic CT

    Science.gov (United States)

    ... lungs; CT scan - chest Images CT scan Thyroid cancer - CT scan Pulmonary nodule, solitary - CT scan Lung mass, right upper ... Chest Injuries and Disorders CT Scans Emphysema Lung Cancer Lung Diseases Pleural Disorders Pneumonia Pulmonary Embolism Tuberculosis Browse the Encyclopedia A.D.A. ...

  20. 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).

  1. 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)

  2. 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.

  3. 3D segmentation of abdominal aorta from CT-scan and MR images.

    Science.gov (United States)

    Duquette, Anthony Adam; Jodoin, Pierre-Marc; Bouchot, Olivier; Lalande, Alain

    2012-06-01

    We designed a generic method for segmenting the aneurismal sac of an abdominal aortic aneurysm (AAA) both from multi-slice MR and CT-scan examinations. It is a semi-automatic method requiring little human intervention and based on graph cut theory to segment the lumen interface and the aortic wall of AAAs. Our segmentation method works independently on MRI and CT-scan volumes and has been tested on a 44 patient dataset and 10 synthetic images. Segmentation and maximum diameter estimation were compared to manual tracing from 4 experts. An inter-observer study was performed in order to measure the variability range of a human observer. Based on three metrics (the maximum aortic diameter, the volume overlap and the Hausdorff distance) the variability of the results obtained by our method is shown to be similar to that of a human operator, both for the lumen interface and the aortic wall. As will be shown, the average distance obtained with our method is less than one standard deviation away from each expert, both for healthy subjects and for patients with AAA. Our semi-automatic method provides reliable contours of the abdominal aorta from CT-scan or MRI, allowing rapid and reproducible evaluations of AAA.

  4. 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 radiat

  5. 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

  6. Response Assessment and Prediction in Esophageal Cancer Patients via F-18 FDG PET/CT Scans

    Science.gov (United States)

    Higgins, Kyle J.

    Purpose: The purpose of this study is to utilize F-18 FDG PET/CT scans to determine an indicator for the response of esophageal cancer patients during radiation therapy. There is a need for such an indicator since local failures are quite common in esophageal cancer patients despite modern treatment techniques. If an indicator is found, a patient's treatment strategy may be altered to possibly improve the outcome. This is investigated with various standard uptake volume (SUV) metrics along with image texture features. The metrics and features showing the most promise and indicating response are used in logistic regression analysis to find an equation for the prediction of response. Materials and Methods: 28 patients underwent F-18 FDG PET/CT scans prior to the start of radiation therapy (RT). A second PET/CT scan was administered following the delivery of ~32 Gray (Gy) of dose. A physician contoured gross tumor volume (GTV) was used to delineate a PET based GTV (GTV-pre-PET) based on a threshold of >40% and >20% of the maximum SUV value in the GTV. Deformable registration was used in VelocityAI software to register the pre-treatment and intra-treatment CT scans so that the GTV-pre-PET contours could be transferred from the pre to intra scans (GTV-intra-PET). The fractional decrease in the maximum, mean, volume to the highest intensity 10%-90%, and combination SUV metrics of the significant previous SUV metrics were compared to post-treatment pathologic response for an indication of response. Next for the >40% threshold, texture features based on a neighborhood gray-tone dimension matrix (NGTDM) were analyzed. The fractional decrease in coarseness, contrast, busyness, complexity, and texture strength were compared to the pathologic response of the patients. From these previous two types of analysis, SUV and texture features, the two most significant results were used in logistic regression analysis to find an equation to predict the probability of a non

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

    Directory of Open Access Journals (Sweden)

    A CHIT SAZ

    2001-09-01

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

  8. Kernohan’s Notch: A Forgotten Cause of Hemiplegia—CT Scans Are Useful in This Diagnosis

    Directory of Open Access Journals (Sweden)

    Ragesh Panikkath

    2013-01-01

    Full Text Available Hemiparesis ipsilateral to a cerebral lesion can be a false localizing sign. This is due to midline shift of the midbrain resulting in compression of the contralateral pyramidal fibers on the tough dural reflection tentorium cerebelli. This may result in partial or complete damage to these fibers. Since these fibers are destined to cross in the medulla and innervate the opposite side of the body, this causes hemiparesis ipsilateral to the site of cerebral lesion. Computed tomography (CT scans have not been used to support the diagnosis of this entity until now. We report a 68-year-old woman with a subdural hematoma who developed ipsilateral hemiparesis without any other explanation (Kernohan’s notch. The CT of the head showed evidence of compression of the midbrain contralateral to the hematoma and was useful in the diagnosis. The purpose of this report is to increase the awareness of this presentation and to emphasize the utility of CT scans to support the diagnosis.

  9. 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

  10. Differentiating intraparenchymal hemorrhage from contrast extravasation on post-procedural noncontrast CT scan in acute ischemic stroke patients undergoing endovascular treatment

    Energy Technology Data Exchange (ETDEWEB)

    Payabvash, Seyedmehdi [Zeenat Qureshi Stroke Institute, Minneapolis, MN (United States); University of Minnesota, Department of Radiology, Minneapolis, MN (United States); Qureshi, Mushtaq H.; Khan, Shayaan M.; Khan, Mahnoor; Majidi, Shahram; Pawar, Swaroop; Qureshi, Adnan I. [Zeenat Qureshi Stroke Institute, Minneapolis, MN (United States)

    2014-09-15

    This study aimed to identify the imaging characteristics that can help differentiate intraparenchymal hemorrhage from benign contrast extravasation on post-procedural noncontrast CT scan in acute ischemic stroke patients after endovascular treatment. We reviewed the clinical and imaging records of all acute ischemic stroke patients who underwent endovascular treatment in two hospitals over a 3.5-year period. The immediate post-procedural CT scan was evaluated for the presence of hyperdense lesion(s). The average attenuation of the lesion(s) was measured. Intraparenchymal hemorrhage was defined as a persistent hyperdensity visualized on follow-up CT scan, 24 h or greater after the procedure. Of the 135 patients studied, 74 (55 %) patients had hyperdense lesion(s) on immediate post-procedural CT scan. Follow-up scans confirmed the diagnosis of intraparenchymal hemorrhage in 20 of these 74 patients. A receiver operating characteristic analysis showed that the average attenuation of the most hyperdense lesion can differentiate intraparenchymal hemorrhage from contrast extravasation with an area under the curve of 0.78 (p = 0.001). An average attenuation of <50 Hounsfield units (HU) in the most visually hyperattenuating hyperdense lesion had 100 % specificity and 56 % sensitivity for identification of contrast extravasations. Petechial hyperdensity was seen in 46/54 (85 %) patients with contrast extravasation versus 9/20 (45 %) patients with intraparenchymal hemorrhage on the immediate post-procedural CT scan (p < 0.001). An average attenuation <50 HU of the most hyperattenuating hyperdense parenchymal lesion on immediate post-procedural CT scan was very specific for differentiating contrast extravasation from intraparenchymal hemorrhage in acute ischemic stroke patients after endovascular treatment. (orig.)

  11. Planned FDG PET-CT Scan in Follow-Up Detects Disease Progression in Patients With Locally Advanced NSCLC Receiving Curative Chemoradiotherapy Earlier Than Standard CT

    DEFF Research Database (Denmark)

    Pan, Yi; Brink, Carsten; Schytte, Tine;

    2015-01-01

    The role of positron emission tomography-computed tomography (PET-CT) in surveillance of patients with nonsmall cell lung cancer (NSCLC) treated with curatively intended chemoradiotherapy remains controversial. However, conventional chest X-ray and computed tomography (CT) are of limited value...... in discriminating postradiotherapy changes from tumor relapse. The aim of this study was to evaluate the clinical value of PET-CT scan in the follow-up for patients with locally advanced (LA) NSCLC receiving concomitant chemoradiotherapy (CCRT).Between 2009 and 2013, eligible patients with stages IIB-IIIB NSCLC...... were enrolled in the clinical trial NARLAL and treated in Odense University Hospital (OUH). All patients had a PET-CT scan scheduled 9 months (PET-CT9) after the start of the radiation treatment in addition to standard follow-up (group A). Patients who presented with same clinical stage of NSCLC...

  12. 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

    2017-03-01

    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.

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

    NARCIS (Netherlands)

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

    2013-01-01

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

  14. CT SCAN FINDINGS IN PATIENTS WITH SEIZURES IN NOTHERN CHHATTISGARH : A RETROSPECTIVE STUDY

    Directory of Open Access Journals (Sweden)

    Archana

    2015-09-01

    Full Text Available A five years study of CT scan findings in seizure patients is carried out to know the different etiology. Seizure is a finite event of altered cerebral function because of excessive and abnormal electrical discharges of the brain cells. Epilepsy is a chronic condition predisposing a person to recurrent seizures. This study is designed to establish usefulness of CT in defining the etiology of seizures in various age groups in people of Northern Chhattisgarh. This is a retrospective hospital - based study conducted in Radio - diagnosis Department of Chhattisgarh Institute of Medical Sciences, Bilaspur, Chhattisgarh. The study was carried out over a 5 year period. Hospital admissions with history of seizures are very common. Almost 3 - 9% p er 1000 population of total hospital emergencies is seizure cases. Epilepsy is an important health problem in developing countries, where its prevalence can be up to 57 per 1000 population. This study has high prevalence of seizures in First, second, third and fourth decades with decreasing pattern with increasing age. Prevalence in first decade is low as compare to second and third decades. Tuberculoma (9.39% and Neurocysticercosis (3.60% has highest prevalence in partial seizures followed by Focal Cereb ral Edema (6.22% whereas Diffuse Cerebral edema (4.91% seen with Generalised Seizures Cerebral infarct has equally seen in both types of seizures. Brain tumour presented mostly with Generalised seizure (2.07% than in partial seizures (0.98% . Other abno rmal findings like Cerebral calcifications, Diffuse cortical atrophy, Focal cortical atrophy, Sub Arachnoid hemorrhage, Intracerebral Hemorrhage, Hypoxic Ischemic Encephalopathy, Hydrocephalus and few rare diseases like Fahr disease and Tuberous sclerosis have also seen in CT scan in seizure patients. CT scan is valuable in making a diagnosis particularly in Indian subcontinent, where infective causes in form of space occupying lesions and infections are most

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

    Directory of Open Access Journals (Sweden)

    Aung Zaw Win

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

  16. Evaluation of Radiation Dose Reduction during CT Scans Using Oxide Bismuth and Nano-Barium Sulfate Shields

    CERN Document Server

    Seoung, Youl-Hun

    2015-01-01

    The purpose of the present study was to evaluate radiation dose reduction and image quality during CT scanning by using a new dose reduction fiber sheet (DRFS) with commercially available bismuth shields. These DRFS were composed of nano-barium sulfate (BaSO4), filling the gaps left by the large oxide bismuth (Bi2O3) particle sizes. The radiation dose was measured five times at directionss of 12 o'clock from the center of the polymethyl methacrylate (PMMA) head phantom to calculate an average value using a CT ionization chamber. The image quality measured CT transverse images of the PMMA head phantom depending on X-ray tube voltages and the type of shielding. Two regions of interest in CT transverse images were chosen from the right and left areas under the surface of the PMMA head phantom and from ion chamber holes located at directions of 12 o'clock from the center of the PMMA head phantom. The results of this study showed that the new DRFS shields could reduce dosages to 15.61%, 23.05%, and 22.71% more in ...

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

    Science.gov (United States)

    Zukauskaite, Ruta; Brink, Carsten; Hansen, Christian Rønn; Bertelsen, Anders; Johansen, Jørgen; Grau, Cai; Eriksen, Jesper Grau

    2016-08-01

    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 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.

  18. Enhancement characteristics of the hepatic parenchyma in CT scanning during splenoportography

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xiu-yi; ZHANG Xue-lin; ZHENG Wei-quan; WANG Jin; WEN Ge

    2002-01-01

    Objective: To evaluate the enhancement characteristics of the hepatic parenchyma during scanning with computed tomography (CT) during splenoportography (CTSP). Methods.. Thirty patients refferred for CTSP were included in the study. Attenuation was measured at different time after contrast medium injection, and time-attenuation curves were created. Enhancement characteristics were evaluated, and the parenchyma-to-tumor difference of attenuation were compared. Results.. CTSP led to high parenchymal enhancement. The highest enhancement value in the left lobe was (218. 0±53. 2) Hu and (246.0± 60. 2) Hu in the right lobe. The difference between the right and left lobes was statistically significant (P<0. 05); The parenchyma-to-tumor difference of (65.3± 25.6) Hu was observed during scanning after injection. Conclusion: The high levels of liver parenchymal enhancement and parenchyma-to-lesion contrast can be achieved within the scanning time with CTSP.

  19. 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

  20. Comparison of linear and non-linear soft tissue models with post-operative CT scan in maxillofacial surgery

    CERN Document Server

    Chabanas, M; Marecaux, C; Swider, P; Boutault, F; Chabanas, Matthieu; Payan, Yohan; Marecaux, Christophe; Swider, Pascal; Boutault, Franck

    2004-01-01

    A Finite Element model of the face soft tissue is proposed to simulate the morphological outcomes of maxillofacial surgery. Three modelling options are implemented: a linear elastic model with small and large deformation hypothesis, and an hyperelastic Mooney-Rivlin model. An evaluation procedure based on a qualitative and quantitative comparison of the simulations with a post-operative CT scan is detailed. It is then applied to one clinical case to evaluate the differences between the three models, and with the actual patient morphology. First results shows in particular that for a "simple" clinical procedure where stress is less than 20%, a linear model seams sufficient for a correct modelling.

  1. In vitro dose measurements in a human cadaver with abdomen/pelvis CT scans

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Da; Padole, Atul; Li, Xinhua; Singh, Sarabjeet; Khawaja, Ranish Deedar Ali; Lira, Diego; Shi, Jim Q.; Otrakji, Alexi; Kalra, Mannudeep K.; Liu, Bob, E-mail: bliu7@mgh.harvard.edu [Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States); Liu, Tianyu; Xu, X. George [Nuclear Engineering Program, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States)

    2014-09-15

    Purpose: To present a study of radiation dose measurements with a human cadaver scanned on a clinical CT scanner. Methods: Multiple point dose measurements were obtained with high-accuracy Thimble ionization chambers placed inside the stomach, liver, paravertebral gutter, ascending colon, left kidney, and urinary bladder of a human cadaver (183 cm in height and 67.5 kg in weight) whose abdomen/pelvis region was scanned repeatedly with a multidetector row CT. The flat energy response and precision of the dosimeters were verified, and the slight differences in each dosimeter's response were evaluated and corrected to attain high accuracy. In addition, skin doses were measured for radiosensitive organs outside the scanned region with OSL dosimeters: the right eye, thyroid, both nipples, and the right testicle. Three scan protocols were used, which shared most scan parameters but had different kVp and mA settings: 120-kVp automA, 120-kVp 300 mA, and 100-kVp 300 mA. For each protocol three repeated scans were performed. Results: The tube starting angle (TSA) was found to randomly vary around two major conditions, which caused large fluctuations in the repeated point dose measurements: for the 120-kVp 300 mA protocol this angle changed from approximately 110° to 290°, and caused 8% − 25% difference in the point dose measured at the stomach, liver, colon, and urinary bladder. When the fluctuations of the TSA were small (within 5°), the maximum coefficient of variance was approximately 3.3%. The soft tissue absorbed doses averaged from four locations near the center of the scanned region were 27.2 ± 3.3 and 16.5 ± 2.7 mGy for the 120 and 100-kVp fixed-mA scans, respectively. These values were consistent with the corresponding size specific dose estimates within 4%. The comparison of the per-100-mAs tissue doses from the three protocols revealed that: (1) dose levels at nonsuperficial locations in the TCM scans could not be accurately deduced by simply scaling

  2. 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

    2015-12-01

    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.

  3. Construction of Abdominal Probabilistic Atlases and Their Value in Segmentation of Normal Organs in Abdominal CT Scans

    Science.gov (United States)

    Park, Hyunjin; Hero, Alfred; Bland, Peyton; Kessler, Marc; Seo, Jongbum; Meyer, Charles

    A good abdominal probabilistic atlas can provide important information to guide segmentation and registration applications in the abdomen. Here we build and test probabilistic atlases using 24 abdominal CT scans with available expert manual segmentations. Atlases are built by picking a target and mapping other training scans onto that target and then summing the results into one probabilistic atlas. We improve our previous abdominal atlas by 1) choosing a least biased target as determined by a statistical tool, i.e. multidimensional scaling operating on bending energy, 2) using a better set of control points to model the deformation, and 3) using higher information content CT scans with visible internal liver structures. One atlas is built in the least biased target space and two atlases are built in other target spaces for performance comparisons. The value of an atlas is assessed based on the resulting segmentations; whichever atlas yields the best segmentation performance is considered the better atlas. We consider two segmentation methods of abdominal volumes after registration with the probabilistic atlas: 1) simple segmentation by atlas thresholding and 2) application of a Bayesian maximum a posteriori method. Using jackknifing we measure the atlas-augmented segmentation performance with respect to manual expert segmentation and show that the atlas built in the least biased target space yields better segmentation performance than atlases built in other target spaces.

  4. Cervical CT scan-guided epidural blood patches for spontaneous intracranial hypotension.

    Science.gov (United States)

    Maingard, Julian; Giles, Lauren; Marriott, Mark; Phal, Pramit M

    2015-12-01

    We describe two patients with spontaneous intracranial hypotension (SIH), presenting with postural headache due to C1-C2 cerebrospinal fluid (CSF) leak. Both patients were refractory to lumbar epidural blood patching (EBP), and subsequently underwent successful CT scan-guided cervical EBP. SIH affects approximately 1 in 50,000 patients, with females more frequently affected. Its associated features are variable, and as such, misdiagnosis is common. Therefore, imaging plays an important role in the diagnostic workup of SIH and can include MRI of the brain and spine, CT myelogram, and radionuclide cisternography. In patients with an established diagnosis and confirmed CSF leak, symptoms will usually resolve with conservative management. However, in a select subgroup of patients, the symptoms are refractory to medical management and require more invasive therapies. In patients with cervical leaks, EBP in the cervical region is an effective management approach, either in close proximity to, or directly targeting a dural defect. CT scan-guided cervical EBP is an effective treatment approach in refractory SIH, and should be considered in those patients who are refractory to conservative management.

  5. 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.

  6. Automatic Calibration Method of Voxel Size for Cone-beam 3D-CT Scanning System

    CERN Document Server

    Yang, Min; Liu, Yipeng; Men, Fanyong; Li, Xingdong; Liu, Wenli; Wei, Dongbo

    2013-01-01

    For cone-beam three-dimensional computed tomography (3D-CT) scanning system, voxel size is an important indicator to guarantee the accuracy of data analysis and feature measurement based on 3D-CT images. Meanwhile, the voxel size changes with the movement of the rotary table along X-ray direction. In order to realize the automatic calibration of the voxel size, a new easily-implemented method is proposed. According to this method, several projections of a spherical phantom are captured at different imaging positions and the corresponding voxel size values are calculated by non-linear least square fitting. Through these interpolation values, a linear equation is obtained, which reflects the relationship between the rotary table displacement distance from its nominal zero position and the voxel size. Finally, the linear equation is imported into the calibration module of the 3D-CT scanning system, and when the rotary table is moving along X-ray direction, the accurate value of the voxel size is dynamically expo...

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

    Science.gov (United States)

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

    2017-03-01

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

  8. Unraveling the hydrodynamics of split root water uptake experiments using CT scanned root architectures and three dimensional flow simulations

    Directory of Open Access Journals (Sweden)

    Nicolai eKoebernick

    2015-05-01

    Full Text Available Split root experiments have the potential to disentangle water transport in roots and soil, enabling the investigation of the water uptake pattern of a root system. Interpretation of the experimental data assumes that water flow between the split soil compartments does not occur. Another approach to investigate root water uptake is by numerical simulations combining soil and root water flow depending on the parameterization and description of the root system. Our aim is to demonstrate the synergisms that emerge from combining split root experiments with simulations. We show how growing root architectures derived from temporally repeated X-ray CT scanning can be implemented in numerical soil-plant models. Faba beans were grown with and without split layers and exposed to a single drought period during which plant and soil water status were measured. Root architectures were reconstructed from CT scans and used in the model R-SWMS (root-soil water movement and solute transport to simulate water potentials in soil and roots in 3D as well as water uptake by growing roots in different depths. CT scans revealed that root development was considerably lower with split layers compared to without. This coincided with a reduction of transpiration, stomatal conductance and shoot growth. Simulated predawn water potentials were lower in the presence of split layers. Simulations showed that this was caused by an increased resistance to vertical water flow in the soil by the split layers. Comparison between measured and simulated soil water potentials proved that the split layers were not perfectly isolating and that redistribution of water from the lower, wetter compartments to the drier upper compartments took place, thus water losses were not equal to the root water uptake from those compartments. Still, the layers increased the resistance to vertical flow which resulted in lower simulated collar water potentials that led to reduced stomatal conductance and

  9. Endolymphatic Sac Tumor Showing Increased Activity on 68Ga DOTATATE PET/CT.

    Science.gov (United States)

    Papadakis, Georgios Z; Millo, Corina; Sadowski, Samira M; Bagci, Ulas; Patronas, Nicholas J

    2016-10-01

    Endolymphatic sac tumors (ELSTs) are rare tumors arising from the epithelium of the endolymphatic sac and duct that can be either sporadic or associated with von Hippel-Lindau (VHL) disease. We report a case of a VHL patient with histologically proven residual ELST who underwent Ga DOTATATE PET/CT showing increased activity (SUVmax, 6.29) by the ELST. The presented case of a VHL-associated ELST with increased Ga DOTATATE uptake indicates cell-surface expression of somatostatin receptors by this tumor, suggesting the potential application of somatostatin receptor imaging using Ga DOTA-conjugated peptides in the workup and management of these patients.

  10. 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....

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

    Directory of Open Access Journals (Sweden)

    Jofizal Jannis

    2004-09-01

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

  12. Optimal scanning protocols of 64-slice CT angiography in coronary artery stents: An in vitro phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Almutairi, Abdulrahman Marzouq [Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University of Technology, Perth, Western Australia (Australia); Sun Zhonghua [Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University of Technology, Perth, Western Australia (Australia)], E-mail: z.sun@curtin.edu.au; Ng, Curtise [Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University of Technology, Perth, Western Australia (Australia); Al-Safran, Zakariya A.; Al-Mulla, Abeer A.; Al-Jamaan, Abdulaziz I. [Department of Medical Imaging, King Fahad Specialist Hospital, Dammam (Saudi Arabia)

    2010-04-15

    Purpose: The purpose of the study was to investigate the optimal scanning protocol of 64-slice CT angiography for assessment of coronary artery stents based on a phantom study. Materials and methods: Coronary stents with a diameter of 2.5 mm was implanted in thin plastic tubes with an inner diameter of 3.0 mm to simulate a coronary artery. The tubes were filled with iodinated contrast medium diluted to 178 HU, closed at both ends and positioned in a plastic container filled with vegetable oil (-70 to -100 HU). A series of scans were performed with a 64-slice CT scanner with the following protocols: section thickness: 0.67 mm, 1.0 mm, 1.5 mm, 2.0 mm, pitch value: 0.2, 0.3, 0.5 and reconstruction interval of 50% overlap of the section thickness. 2D axial and multiplanar reformatted images were generated to assess the visibility of stent lumen, while virtual intravascular endoscopy (VIE) was reconstructed to evaluate the artery wall and stent surface. Results: Our results showed that a scanning protocol of 1.0 mm slice thickness with a pitch of 0.3 produced acceptable images with best demonstration of the intrastent lumen and stent surface with minimal image noise or artifacts. In contrast, submillimeter scans with 0.67 mm resulted in moderate artifacts which affected visualization of the coronary lumen, in addition to the increased noise. When the section thickness increased to 1.5 mm and 2.0 mm, visualization of the artery wall and stent surface was compromised, although the intrastent lumen was still visible. Conclusion: Our in vitro study suggested that a scanning protocol of 1.0 mm section thickness with pitch of 0.3 is the optimal protocol for evaluation of coronary artery stents as it allows generation of acceptable images with better visualization of stent lumen, stent surface and coronary artery wall.

  13. Observation on local and/or unilateral pathologic changes in renal cortex by CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Ishikawa, Isao; Shinoda, Akira (Kanazawa Medical Univ. (Japan)); Onouchi, Zengoro; Saito, Yasuhito; Matsuura, Hajime

    1984-03-01

    Renal cortex visualization after bolus injection of contrast medium using computed tomography (CT), was obtained in 132 consecutive patients with renal disease. Local pathological changes in the functioning cortex of the kidney were easily recognized in 37 cases and unilateral cortical thinning was found in 17 cases. Unilateral poor enhancement of the cortex with bilateral equal cortex thickness was noted in 4 cases. Several representative cases are reported with CT scans. The cortex at the posterior aspect of the renal graft compressed on psoas muscle was thinner than that at the anterior aspect in renal transplant cases. The macroscopic observation on the renal cortex presented here is far superior to the nephrogram or pyelogram seen through conventional radiographic examination. In vivo cortex visualization will correlate renal biopsy findings with the state of the whole kidney.

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

    Energy Technology Data Exchange (ETDEWEB)

    Oldham, M; Clift, C; Thomas, A; Farfan, E; Foley, T; Jannik, T; Adamovics, J; Holmes, C; Stanley, S, E-mail: Mark.Oldham@Duke.ed

    2010-11-01

    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.

  15. 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.

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

    Directory of Open Access Journals (Sweden)

    Sierink Joanne C

    2012-03-01

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

  17. Construction and analysis of a head CT-scan database for craniofacial reconstruction.

    Science.gov (United States)

    Tilotta, Françoise; Richard, Frédéric; Glaunès, Joan; Berar, Maxime; Gey, Servane; Verdeille, Stéphane; Rozenholc, Yves; Gaudy, J F

    2009-10-30

    This paper is devoted to the construction of a complete database which is intended to improve the implementation and the evaluation of automated facial reconstruction. This growing database is currently composed of 85 head CT-scans of healthy European subjects aged 20-65 years old. It also includes the triangulated surfaces of the face and the skull of each subject. These surfaces are extracted from CT-scans using an original combination of image-processing techniques which are presented in the paper. Besides, a set of 39 referenced anatomical skull landmarks were located manually on each scan. Using the geometrical information provided by triangulated surfaces, we compute facial soft-tissue depths at each known landmark positions. We report the average thickness values at each landmark and compare our measures to those of the traditional charts of [J. Rhine, C.E. Moore, Facial Tissue Thickness of American Caucasoïds, Maxwell Museum of Anthropology, Albuquerque, New Mexico, 1982] and of several recent in vivo studies [M.H. Manhein, G.A. Listi, R.E. Barsley, et al., In vivo facial tissue depth measurements for children and adults, Journal of Forensic Sciences 45 (1) (2000) 48-60; S. De Greef, P. Claes, D. Vandermeulen, et al., Large-scale in vivo Caucasian facial soft tissue thickness database for craniofacial reconstruction, Forensic Science International 159S (2006) S126-S146; R. Helmer, Schödelidentifizierung durch elektronische bildmischung, Kriminalistik Verlag GmbH, Heidelberg, 1984].

  18. 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.

  19. Reducing the throughput time of the diagnostic track involving CT scanning with computer simulation

    Energy Technology Data Exchange (ETDEWEB)

    Lent, Wineke A.M. van, E-mail: w.v.lent@nki.nl [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital (NKI-AVL), P.O. Box 90203, 1006 BE Amsterdam (Netherlands); University of Twente, IGS Institute for Innovation and Governance Studies, Department of Health Technology Services Research (HTSR), Enschede (Netherlands); Deetman, Joost W., E-mail: j.deetman@nki.nl [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital (NKI-AVL), P.O. Box 90203, 1006 BE Amsterdam (Netherlands); Teertstra, H. Jelle, E-mail: h.teertstra@nki.nl [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital (NKI-AVL), P.O. Box 90203, 1006 BE Amsterdam (Netherlands); Muller, Sara H., E-mail: s.muller@nki.nl [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital (NKI-AVL), P.O. Box 90203, 1006 BE Amsterdam (Netherlands); Hans, Erwin W., E-mail: e.w.hans@utwente.nl [University of Twente, School of Management and Governance, Dept. of Industrial Engineering and Business Intelligence Systems, Enschede (Netherlands); Harten, Wim H. van, E-mail: w.v.harten@nki.nl [Netherlands Cancer Institute - Antoni van Leeuwenhoek Hospital (NKI-AVL), P.O. Box 90203, 1006 BE Amsterdam (Netherlands); University of Twente, IGS Institute for Innovation and Governance Studies, Department of Health Technology Services Research (HTSR), Enschede (Netherlands)

    2012-11-15

    Introduction: To examine the use of computer simulation to reduce the time between the CT request and the consult in which the CT report is discussed (diagnostic track) while restricting idle time and overtime. Methods: After a pre implementation analysis in our case study hospital, by computer simulation three scenarios were evaluated on access time, overtime and idle time of the CT; after implementation these same aspects were evaluated again. Effects on throughput time were measured for outpatient short-term and urgent requests only. Conclusion: The pre implementation analysis showed an average CT access time of 9.8 operating days and an average diagnostic track of 14.5 operating days. Based on the outcomes of the simulation, management changed the capacity for the different patient groups to facilitate a diagnostic track of 10 operating days, with a CT access time of 7 days. After the implementation of changes, the average diagnostic track duration was 12.6 days with an average CT access time of 7.3 days. The fraction of patients with a total throughput time within 10 days increased from 29% to 44% while the utilization remained equal with 82%, the idle time increased by 11% and the overtime decreased by 82%. The fraction of patients that completed the diagnostic track within 10 days improved with 52%. Computer simulation proved useful for studying the effects of proposed scenarios in radiology management. Besides the tangible effects, the simulation increased the awareness that optimizing capacity allocation can reduce access times.

  20. 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.

  1. SU-D-217A-06: Impact of Anterior-Posterior (AP) and Posterior-Anterior (PA) Scout Scans on the CT Radiation Dose in the Whole Body PET/CT Scan.

    Science.gov (United States)

    Luo, D; Pan, T

    2012-06-01

    CT can contribute over 50% of radiation dose in the whole body (WB) PET/CT scan. Tube current modulation (TCM) is a standard technique for reducing CT radiation dose to the patient by changing the tube current with the patient size, and is controlled by a very low-dose scoutscan, which assumes the patient is positioned at the center of the CT gantry opening. However, most patients are not positioned at the center due to practicality or to avoid claustrophobic or to reduce time of radiation exposure from the patient to the technologist. We study the impact of the AP and PA scout scans to the patient radiation exposure from CT. Ina retrospective study of 200 patients, each received two WB PET/CT scans: one with AP, and the other one with PA. The helical CT with TCM and PET acquisitions were identical in both scans. Separation of the two scans was about 10 months in average. The scans were performed on four GE PET/CT scanners: three 16- and one 64-slice with the same TCM settings. The 200patients were selected for the same scan coverage and similar body weight (difference = 3 kg). The tube current in each slice and average exposure tothe patient were recorded and compared. The AP scout caused lower radiation dose on 94% of the patients. Both the tube current, and radiation exposure were reduced by 46±30 mA and 1.6±1.0 mGy, respectively. The effective radiation dose is reduced by 1.7±1.2 mSv. These results were statistically significant (p<0.00001). The AP scout caused significantly less radiation dose than the PA scout in the CT scan of the whole-body PET/CT scan. Care should be taken to select theorientation of the scout scan to achieve appropriate radiation exposure to the patient when TCM is applied. © 2012 American Association of Physicists in Medicine.

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

    Directory of Open Access Journals (Sweden)

    Khalilpour M

    2009-07-01

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

  3. [Retrospective computation of the ISS in multiple trauma patients: Potential pitfalls and limitations of findings in full body CT scans].

    Science.gov (United States)

    Bogner, V; Brumann, M; Kusmenkov, T; Kanz, K G; Wierer, M; Berger, F; Mutschler, W

    2016-03-01

    The Injury Severity Score (ISS) is a well-established anatomical scoring system for polytraumatized patients. However, any inaccuracy in the Abbreviated Injury Score (AIS) directly increases the ISS impreciseness. Using the full body computed tomography (CT) scan report, ISS computation can be associated with certain pitfalls. This study evaluates interpretation variations depending on radiological reports and indicates requirements to reliably determine the ISS. The ISS of 81 polytraumatized patients was calculated based on the full body CT scan report. If an injury could not be attributed to a precise AIS cipher, the minimal and maximal ISS was computed. Real ISS included all conducted investigations, intraoperative findings, and final medical reports. The differences in ISS min, ISS max, and ISS real were evaluated using the Kruskal-Wallis test (pISS min was 24.0 (± 0.7 SEM) points, mean ISS real 38.6 (±1.3 SEM) and mean ISS max was 48.3 (±1.4 SEM) points. All means were significantly different compared to one another (pISS showed a distinctive variation. Mean deviation was 9.7 (±0.9 SEM) points downward and 14.5 (±1.1 SEM) points upward. The difference between deviation to ISS min and ISS max was highly significant (pISS is an internationally well-established method in clinical and scientific settings. The full body CT scan report must meet distinct criteria and has to be written in acquaintance to the AIS scale if intended to be used for correct ISS computation.

  4. Skeletal idiopathic osteosclerosis helps to perform personal identification of unknown decedents: A novel contribution from anatomical variants through CT scan.

    Science.gov (United States)

    De Angelis, D; Gibelli, D; Palazzo, E; Sconfienza, L; Obertova, Z; Cattaneo, C

    2016-07-01

    Personal identification consists of the comparison of ante-mortem information from a missing person with post-mortem data obtained from an unidentified corpse. Such procedure is based on the assessment of individualizing features which may help in providing a conclusive identification between ante-mortem and post-mortem material. Anatomical variants may provide important clues to correctly identify human remains. Areas of idiopathic osteosclerosis (IO), or dense bone islands (DBIs) characterized by radiopaque areas of dense, trabeculated, non-inflamed vital bone represent one of these, potentially individualizing, anatomical features. This study presents a case where the finding of DBI was crucial for a positive identification through CT-scan. A decomposed body was found in an apartment in June 2014 in advanced decomposition and no dental records were available to perform a comparison for positive identification. Genetic tests were not applicable because of the lack of relatives in a direct line. The analysis of the only ante-mortem documentation, a CT-scan to the deceased dating back to August 2009, showed the presence of three DBIs within the trabecular bone of the proximal portion of the right femur. The same bony district was removed from the corpse during the autopsy and analysed by CT-scan, which verified the presence of the same features. Forensic practitioners should therefore be aware of the great importance of anatomical bone variants, such as dense bone islands for identification purposes, and the importance of advanced radiological technique for addressing the individualizing potential of such variants. We propose that anatomical variants of the human skeleton should be considered as being "primary identification characteristics" similar to dental status, fingerprints and DNA.

  5. Comparative study on measured variables and sensitivity to bone microstructural changes induced by weightlessness between in vivo and ex vivo micro-CT scans.

    Science.gov (United States)

    Sun, Lian Wen; Wang, Chao; Pu, Fang; Li, De Yu; Niu, Hai Jun; Fan, Yu Bo

    2011-01-01

    Depending on the experimental design, micro-CT can be used to examine bones either in vivo or ex vivo (excised fresh or formalin-fixed). In this study we investigated if differences exist in the variables measured by micro-CT between in vivo and ex vivo scans and which kind of scan is more sensitive to the changes of bone microstructure induced by simulated weightlessness. Rat tail suspension was used to simulate the weightless condition. The same bone from either normal or tail-suspended rats was scanned by micro-CT both in vivo and ex vivo (fresh and fixed by formalin). Then, bone mineral density (BMD) and microstructural characteristics were analyzed. The results showed that no significant differences existed in the microstructural parameters of trabecular bone among in vivo, fresh, and formalin-fixed bone scans from both femurs and tibias, although BMD exhibited differences. On the other hand, most parameters of the tail-suspended rats measured by micro-CT deteriorated compared with controls. Ex vivo scanning appeared to be more sensitive to bone microstructural changes induced by tail suspension than in vivo scanning. In general, the results indicate that values obtained in vivo and ex vivo (fresh and fixed) are comparable, thus allowing for meaningful comparison of experimental results from different studies irrespective of the type of scans. In addition, this study suggests that it is better to use ex vivo scanning when evaluating bone microstructure under weightlessness. However, researchers can select any type of scan depending upon the objective and the demands of the experiment.

  6. 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

  7. 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.

  8. ANATOMICAL VARIATIONS IN SINONASAL REGION IN CASES OF SINUS HEADACHE - CT SCAN - PNS STUDY

    Directory of Open Access Journals (Sweden)

    Arun Kumar

    2015-08-01

    Full Text Available BACKGROUND: Sinus headache secondary to Chronic Rhinosinusitis refers to episode of pain over the sinus area of the face and is often associated with nasal congestion, rhinorrhea, facial pressure, lacrimation, nausea and sensory sensitivity. Any small lesions or anatomical variations over lateral wall of nose may giv e rise to sinus headache. CT scan play a vital role in accurate assessment of osteomeatal complex area and anatomical variations at this site. AIM: To study anatomical variations of osteomeatal complex area and deviated septum in cases of chronic sinus hea dache secondary to Chronic Rhinosinusitis. MATERIALS AND METHODS : This study was conducted in Jhalawar Medical College, ENT Department between Sept. 2012 to Dec. 2014. In this study 75 patients withchronic sinus headache was selected who had chronic headac he for more than 3 months duration not responding to medical line of treatment and who were willing to undergo function endoscopic sinus surgery. All patients underwent for CT scan para nasal sinus. RESULT: In this study deviated nasal septum was found in 77.33% patients, apart from that it was observed that 54.66% of the sinus headache cases had two or more anatomical variations and 28% had single anatomical variations, out of them commonest finding is concha bullosa followed by enlarge bulla ethmoid, para doxical middle turbinate, medialiseduncinate process, lateraliseduncinate process, prominent aggar nasi cells, haller cells and onodi cells in decreasing order . CONCLUSION: The study of CT scan PNS conclude that Deviated Nasal Septum and anatomical variati ons at lateral wall of nose causes narrowing of osteomeatal complex area which predisposed patients to sino nasal disease and sinus headache

  9. 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.

  10. 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.

  11. Anatomic Variation of Sphenoid Sinus and Related Structures in Libyan Population: CT Scan Study

    Directory of Open Access Journals (Sweden)

    Hewaidi GH

    2008-01-01

    Full Text Available Background: Sphenoid sinus is the most inaccessible paranasal sinus, enclosed within the sphenoid bone and intimately related to numerous vital neural and vascular structures. Anatomic variation of the sphenoid sinus is well documented and may complicate surgery in such a place. Objective: To outline the surgically risky anatomic variants of the sphenoid sinus as well as the variable relationships between the sinus and related neurovascular structures, for the safe removal of intrasphenoid and pituitary lesions. Materials and Methods: We undertook a prospective review of 300 paranasal sinus CT scans of Libyan patients; coronal CT scans were obtained by special parameter techniques. We assessed pneumatization of pterygoid process (PP, anterior clinoid process (ACP, and greater wing of sphenoid (GWS; we also examined protrusion and dehiscence of internal carotid artery (ICA, optic nerve (ON, maxillary nerve (MN, and vidian nerve (VN into the sphenoid sinus cavity. Results: Pneumatization of PP, ACP, and GWS were seen in 87 (29%, 46 (15.3%, and 60 patients (20%, respectively. Protrusion of ICA, ON, MN, and VN were noticed in 123 (41%, 107 (35.6%, 73 (24.3%, and 81 patients (27%, respectively; dehiscence of these structures was encountered in 90 (30%, 92 (30.6%, 39 (13%, and 111 patients (37%, respectively. Statistically, there was a highly significant association between ACP pneumatization and ICA protrusion, ACP pneumatization and ON protrusion, PP pneumatization and VN protrusion; and GWS pneumatization and MN protrusion (p-value < 0.001. Conclusion: The sphenoid sinus is highly variable; this variability necessitates a comprehensive understanding of the regional sphenoid sinus anatomy by a detailed CT scan sinus examination before surgery in and around the sinus. This study indicates the possibility of a racial anatomical variation of the sphenoid sinus in the Libyan population.

  12. 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.

  13. CT Scan and Pulmonary Sequestration%CT扫描与肺隔离症

    Institute of Scientific and Technical Information of China (English)

    刘秀梅

    2015-01-01

    目的:分析CT增强扫描对肺隔离症的价值。方法回顾性分析经手术病理证实的17例肺隔离症患者。结果手术病理证实2例为叶外型,15例为叶内型,均位于两肺下叶。呈实性肿块的4例,呈囊性的5例(其中2例可见气液平面),呈囊实性肿块的7例。CT增强扫描均可见异常的供血动脉。结论 CT增强扫描清晰显示肺隔离症的异常体动脉血供,在鉴别诊断中具有重大价值。%Objective To analyse the value of constrast-enhanced Routine CT in pulmonary sequestration.Methods The contrast-enhanced Routine CT of 17 patients of pulmonary sequestration were retrospectively studied. They were al proved by surgery.Results There were 2 extra-lober sequestration and 15 intra-lober sequestration in the 17 patients. The lesions of the17 cases located in both lower lobar. 4 of them were solid and 5 were cystic,(2 of 5 cases had air fluid level.),and 7 were cystic and soild.contrast-enhanced Routine CT successfuly delineated abnormal systemic artery.Conclusion Contrast-enhanced Routine CT scan display abnormal systemic artery. Contrast-enhanced Routine CT have important evalution in the distinguish of pulmonary sequestration.

  14. Interapophyseal joint synovial cyst of lumbar spine. CT scan and MR imaging correlation in two cases

    Energy Technology Data Exchange (ETDEWEB)

    Granat, O.; Jeanbourquin,D.; Perfettini, C.; Pernot, P.; Ducolombier, A.; Cosnard, G.

    1987-05-01

    Two patients presenting with L5 radiculagia were investigated by CT scan imaging. The origin of the pain was determined with certitude as arising from intraspinal development of an interapophyseal synovial cyst. Examination of the two cases by MR imaging provided conflicting results: in one patient images obtained by MR were not contributive and the synovial cyst would probably have been missed while in the other patient images were specific and very sensitive for diagnosis of interapophyseal synovial lesions. Treatment was surgical in both cases.

  15. Image reconstruction for view-limited x-ray CT in baggage scanning

    Science.gov (United States)

    Mandava, Sagar; Coccarelli, David; Greenberg, Joel A.; Gehm, Michael E.; Ashok, Amit; Bilgin, Ali

    2017-05-01

    X-ray CT based baggage scanners are widely used in security applications. Recently, there has been increased interest in view-limited systems which can improve the scanning throughput while maintaining the threat detection performance. However as very few view angles are acquired in these systems, the image reconstruction problem is challenging. Standard reconstruction algorithms such as the filtered backprojection create strong artifacts when working with view-limited data. In this work, we study the performance of a variety of reconstruction algorithms for both single and multi-energy view-limited systems.

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

    CSIR Research Space (South Africa)

    Kirkbride, AN

    1997-04-01

    Full Text Available : To place article links in an external web document, simply copy and paste the HTML below, starting with "CT scans for Sts 14 provide the potential for manufacturing casts. Authors: Yates, Simon C. Kirkbride, Anthony N. Source...

  17. Evaluating soft tissue simulation in maxillofacial surgery using pre and post-operative CT scan

    CERN Document Server

    Chabanas, M; Chouly, F; Boutault, F; Payan, Y; Chabanas, Matthieu; Marecaux, Christophe; Chouly, Franz; Boutault, Franck; Payan, Yohan

    2004-01-01

    One of the most important issue in soft tissue modeling is to assess the quality of the simulations. A validation protocol is presented based on two CT scans of the patient acquired before and after cranio-maxillofacial surgery. The actual bones repositioning realized during the intervention are accurately measured and reproduced. A evaluation of the soft tissue deformation is then computed using a finite element model of the face. The simulations are therefore compared, qualitatively and quantitatively, with the actual outcome of the surgery. This protocol enable to rigorously evaluate different modeling methods, and to assess the clinical relevance of soft tissue simulation in maxillofacial surgery.

  18. Bone marrow trephine biopsy in Hodgkin's lymphoma. Comparison with PET-CT scan in 65 patients.

    Science.gov (United States)

    Lakhwani, Sunil; Cabello-García, Dolores; Allende-Riera, Ana; Cárdenas-Negro, Carlos; Raya, José María; Hernández-Garcia, Miguel T

    2017-08-29

    To compare bone marrow biopsy (BMB) and PET/CT in detecting bone marrow involvement in Hodgkin's lymphoma MATERIAL AND METHODS: Retrospective analysis of 65 patients with both tests in the initial staging or in relapse with special attention to the PET/CT uptake pattern. In 3 patients (4.6%), the BMB showed bone marrow involvement with the PET/CT being positive in them all: 2 with diffuse+multifocal pattern and one diffuse only. In 11 additional patients (total 14/65, 21%), bone marrow involvement was diagnosed by PET/CT because bone marrow uptake was above hepatic one. The pattern was focal only in 2 cases, multifocal in 5, diffuse in 3 and diffuse+multifocal in one. In these last 4 cases the BMB showed an unspecific myelopathy. PET/CT detects all cases with BMB affected and many that escape to biopsy, however when the uptake pattern is diffuse it could be by involvement or reactive hyperplasia and in those cases the BMB should be done. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

  19. The pros and cons of intraoperative CT scan in evaluation of deep brain stimulation lead implantation: A retrospective study

    Science.gov (United States)

    Servello, Domenico; Zekaj, Edvin; Saleh, Christian; Pacchetti, Claudio; Porta, Mauro

    2016-01-01

    Background: Deep brain stimulation (DBS) is an established therapy for movement disorders, such as Parkinson's disease (PD), dystonia, and tremor. The efficacy of DBS depends on the correct lead positioning. The commonly adopted postoperative radiological evaluation is performed with computed tomography (CT) scan and/or magnetic resonance imaging (MRI). Methods: We conducted a retrospective study on 202 patients who underwent DBS from January 2009 to October 2013. DBS indications were PD, progressive supranuclear palsy, tremor, dystonia, Tourette syndrome, obsessive compulsive disorder, depression, and Huntington's disease. Preoperatively, all patients underwent brain MRI and brain CT scan with the stereotactic frame positioned. The lead location was confirmed intraoperatively with CT. The CT images were subsequently transferred to the Stealth Station Medtronic and merged with the preoperative planning. On the first or second day after, implantation we performed a brain MRI to confirm the correct position of the lead. Results: In 14 patients, leads were in suboptimal position after intraoperative CT scan positioning. The cases with alteration in the Z-axis were corrected immediately under fluoroscopic guidance. In all the 14 patients, an immediate repositioning was done. Conclusions: Based on our data, intraoperative CT scan is fast, safe, and a useful tool in the evaluation of the position of the implanted lead. It also reduces the patient's discomfort derived from the transfer of the patient from the operating room to the radiological department. However, intraoperative CT should not be considered as a substitute for postoperative MRI. PMID:27583182

  20. Clinical significance of multislice spiral CT scans in hepatic veins occlusion in Budd-Chiari syndrome

    Institute of Scientific and Technical Information of China (English)

    MENG Xiao-chun; ZHU Kang-shun; QIN Jie; ZHANG Jian-sheng; WANG Xiao-hong; ZOU Yan; ZHANG Ya-qin; SHAN Hong

    2007-01-01

    Background Budd-Chiari syndrome with hepatic vein occlusion (HVBCS) can induce severe portal hypertension and liver damage. We retrospectively analyzed hepatic CT features of HVBCS and evaluated the usefulness of triphasic enhancement of CT examinations and CT angiography (CTA) in its diagnosis.Methods Twenty-five cases with HVBCS, confirmed by digital subtraction angiography (DSA), received a triphasic enhancement CT scan within one week before DSA. The CTA images of the relevant blood vessels were reconstructed with maximum intensity projection, volume rendering and oblique reformat techniques.Results Compared with DSA, the detection rate of transverse CT and CTA images for abnormal hepatic vein were 81.7% (58/71) and 95.8% (68/71) (χ2=7.044, P=0.008), for membranous obstruction were 47.4% (9/19) and 84.2% (16/19) respectively (χ2 =5.729, P=0.017 ), for segmental obstruction were 88.0% (22/25) and 100% (25/25) respectively (χ2=1.418, P=0.234). The detection rates for hepatic vein stenosis were 100% with each method. Diffuse hepatomegaly was found in all 6 cases in acute phase and 3 of 19 cases in chronic phase who had severe obstruction of three hepatic veins without patent intrahepatic collaterals. The other 16 cases in chronic phase had hepatatrophia to different extents related to the obstructed hepatic vein. All in acute phase and 15 in chronic phase presented typical patchy enhancement initially in caudate lobe and perihilar areas and enlarged with time delay. In all cases, parenchyma areas with atrophy, necrosis and congestion demonstrated lower and later enhancement. In all the parts, which had normal enhancement at least one patent outflow hepatic vein, accessory hepatic vein or collateral vessel was detected. Conclusion Dynamic enhancement CT examination by multislice spiral CT not only could improve the diagnosis of HVBCS by CTA technique, but also could noninvasively provide anatomical information and reveal damage to the hepatic parenchyma.

  1. Importance of bony analysis for interpreting ear CT scans: part three; ORL - tomodensitometrie de l'oreille. Interet de l'analyse osseuse dans l'interpretation des scanners de l'oreille (troisieme partie)

    Energy Technology Data Exchange (ETDEWEB)

    Serhal, M.; Dordea, M.; Cymbalista, M. [Hopital de Montfermeil, Service de Radiologie, 93 - Montfermeil (France); Halimi, P. [Hopital Europeen Georges-Pompidou, Service de Radiologie, 75 - Paris (France); Iffenecker, C. [Clinique Radiologique, 62 - Boulogne sur Mer (France); Bensimon, J.L

    2003-02-01

    The accurate description of bony changes in ear CT scans has a great diagnostic and therapeutic impact. The third part shows the way to analyze bone remodeling when CT scan is performed for tumors in the vicinity of the temporal bone, for intra temporal lesions of the facial nerve and for external auditory canal malformations. It demonstrates how bony analysis should be included in postoperative report of ear CT scan. The importance of bony signs in tumors and pseudo tumors of the inner ear are outlined. (authors)

  2. 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

  3. 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

  4. 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.

  5. 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

  6. Risk stratification of non-contrast CT beyond the coronary calcium scan.

    Science.gov (United States)

    Madaj, Paul; Budoff, Matthew J

    2012-01-01

    Coronary artery calcification (CAC) is a well-known marker for coronary artery disease and has important prognostic implications. CAC is able to provide clinicians with a reliable source of information related to cardiovascular atherosclerosis, which carries incremental information beyond Framingham risk. However, non-contrast scans of the heart provide additional information beyond the Agatston score. These studies are also able to measure various sources of fat, including intrathoracic (eg, pericardial or epicardial) and hepatic, both of which are thought to be metabolically active and linked to increased incidence of subclinical atherosclerosis as well as increased prevalence of type 2  diabetes. Testing for CAC is also useful in identifying extracoronary sources of calcification. Specifically, aortic valve calcification, mitral annular calcification, and thoracic aortic calcium (TAC) provide additional risk stratification information for cardiovascular events. Finally, scanning for CAC is able to evaluate myocardial scaring due to myocardial infarcts, which may also add incremental prognostic information. To ensure the benefits outweigh the risks of a scanning for CAC for an appropriately selected asymptomatic patient, the full utility of the scan should be realized. This review describes the current state of the art interpretation of non-contrast cardiac CT, which clinically should go well beyond coronary artery Agatston scoring alone.

  7. The use of a new 3D splint and double CT scan procedure to obtain an accurate anatomic virtual augmented model of the skull.

    Science.gov (United States)

    Swennen, G R J; Barth, E-L; Eulzer, C; Schutyser, F

    2007-02-01

    Three-dimensional (3D) virtual planning of orthognathic surgery requires detailed visualization of the interocclusal relationship. The purpose of this study was to introduce the modification of the double computed tomography (CT) scan procedure using a newly designed 3D splint in order to obtain a detailed anatomic 3D virtual augmented model of the skull. A total of 10 dry adult human cadaver skulls were used to evaluate the accuracy of the automatic rigid registration method for fusion of both CT datasets (Maxilim, version 1.3.0). The overall mean registration error was 0.1355+/-0.0323 mm (range 0.0760-0.1782 mm). Analysis of variance showed a registration method error of 0.0564 mm (P 3D splint with the double CT scan procedure allowed accurate registration and the set-up of an accurate anatomic 3D virtual augmented model of the skull with detailed dental surface.

  8. 低剂量CT扫描颅内出血性疾病%Low-dose CT Scanning of Intracranial Hemorrhagic Disease

    Institute of Scientific and Technical Information of China (English)

    魏应敏; 毛存南

    2014-01-01

    Objective To explore the application of low-dose CT scanning in intracranial hemorrhagic disease. To study the feasibility of low-dose scans in the clinical diagnosis. Methods German Siemens 16-slice spiral CT was used. The scanning dose was reduced by reducing the tube current. 60 cases with intracranial bleeding diseases underwent CT scanning. 30 patients underwent conventional CT scanning, and another 30 cases underwent low-dose CT scanning. Low-dose CT images were compared to the first checked images to evaluate the development of hemorrhagic disease, and compared with conventional CT scanning images. Results Compared with the first scanning images, low-dose CT scanning images showed no significant difference, and the quality of images did not affect the display of lesions and diagnosis. There was no significant difference compared to conventional CT images. Conclusion The patient's radiation dose was significantly reduced by low-dose CT scanning. As a result of low-dose scanning, the consumption of CT machine was also reduced, which could greatly increase the life of machine.%目的:探讨低剂量CT扫描在颅内出血性疾病复查时扫描的应用价值。并研究低剂量扫描在临床诊断中的可行性。方法采用德国西门子公司生产的16排螺旋CT,通过降低管电流来降低扫描剂量,对60例颅内出血性疾病患者复查扫描。其中30例采用常规扫描,另外30例采用低剂量扫描。将低剂量扫描的图像与首次检查图像比较,评价出血性疾病的发展情况。再与常规扫描比较影像学差异。结果低剂量CT扫描所获得的图像清晰,与首次扫描的图像相比,对比度、病灶边缘显示无明显差异,不影响病灶的显示和诊断结果。与常规扫描图像无明显影像学差异。结论低剂量CT扫描对病人的辐射剂量大大降低了。由于采用低剂量扫描,CT机器的消耗也降低了,大大增加了机器的使用寿命。

  9. Angiogenesis in tissue-engineered nerves evaluated objectively using MICROFIL perfusion and micro-CT scanning

    Institute of Scientific and Technical Information of China (English)

    Hong-kui Wang; Ya-xian Wang; Cheng-bin Xue; Zhen-mei-yu Li; Jing Huang; Ya-hong Zhao; Yu-min Yang; Xiao-song Gu

    2016-01-01

    Angiogenesis is a key process in regenerative medicine generally, as well as in the speciifc ifeld of nerve regeneration. However, no conve-nient and objective method for evaluating the angiogenesis of tissue-engineered nerves has been reported. In this study, tissue-engineered nerves were constructedin vitro using Schwann cells differentiated from rat skin-derived precursors as supporting cells and chitosan nerve conduits combined with silk ifbroin ifbers as scaffolds to bridge 10-mm sciatic nerve defects in rats. Four weeks after surgery, three-di-mensional blood vessel reconstructions were made through MICROFIL perfusion and micro-CT scanning, and parameter analysis of the tissue-engineered nerves was performed. New blood vessels grew into the tissue-engineered nerves from three main directions: the prox-imal end, the distal end, and the middle. The parameter analysis of the three-dimensional blood vessel images yielded several parameters, including the number, diameter, connection, and spatial distribution of blood vessels. The new blood vessels were mainly capillaries and microvessels, with diameters ranging from 9 to 301µm. The blood vessels with diameters from 27 to 155µm accounted for 82.84% of the new vessels. The microvessels in the tissue-engineered nerves implantedin vivo were relatively well-identiifed using the MICROFIL perfusion and micro-CT scanning method, which allows the evaluation and comparison of differences and changes of angiogenesis in tis-sue-engineered nerves implantedin vivo.

  10. Comparative analysis of realistic CT-scan and simplified human airway models in airflow simulation.

    Science.gov (United States)

    Johari, Nasrul Hadi; Osman, Kahar; Helmi, Nor Harris N; Abdul Kadir, Mohammed A Rafiq

    2015-01-01

    Efforts to model the human upper respiratory system have undergone many phases. Geometrical proximity to the realistic shape has been the subject of many research projects. In this study, three different geometries of the trachea and main bronchus were modelled, which were reconstructed from computed tomography (CT) scan images. The geometrical variations were named realistic, simplified and oversimplified. Realistic refers to the lifelike image taken from digital imaging and communications in medicine format CT scan images, simplified refers to the reconstructed image based on natural images without realistic details pertaining to the rough surfaces, and oversimplified describes the straight wall geometry of the airway. The characteristics of steady state flows with different flow rates were investigated, simulating three varied physical activities and passing through each model. The results agree with previous studies where simplified models are sufficient for providing comparable results for airflow in human airways. This work further suggests that, under most exercise conditions, the idealised oversimplified model is not favourable for simulating either airflow regimes or airflow with particle depositions. However, in terms of immediate analysis for the prediction of abnormalities of various dimensions of human airways, the oversimplified techniques may be used.

  11. AIDS complicated with intestinal lymphoma: X-ray radiology,CT scan and pathological findings

    Institute of Scientific and Technical Information of China (English)

    LI Hong-jun; CHENG Jing-liang

    2011-01-01

    Background The non-Hodgkin's lymphoma is the AIDS symbol of tumor, with high incidence and poor prognosis. The purpose of this study was to investigate the radiological demonstrations of AIDS complicated by intestinal lymphoma and its pathological mechanism.Methods CT scan and pathological data of 3 cases of AIDS complicated by intestinal lymphoma were retrospectively analyzed. All the 3 cases received CT diagnostic scanning, including 2 receiving barium enema radiography after lower gastrointestinal tract cleansing, 1 receiving laporotomy to obtain partial thickened intestinal canal for histopathology and 1with autopsy for histopathological analysis.Results Intestinal canal lymphoma occurred at the left intestinal canal in 2 cases and at the right intestinal canal in the other case, with manifestations of unevenly thickened intestinal canal wall, narrowed canal lumen and filling defect. It was pathologically classified as B cell lymphoma.Conclusions AIDS complicated by B cell lymphoma has manifestations of unevenly thickened intestinal canal wall and narrowed canal lumen, which are non-specific. It should be differentiated from other tumors of intestinal canal in its diagnosis.

  12. Radiological Appearance of Extrapulmonary Lesions in Rradiography (CT scan-MRI

    Directory of Open Access Journals (Sweden)

    A. Soltani Shirazi

    2005-08-01

    Full Text Available Introduction & Background: To make the diagnosis of chest lesions in chest radiography or CT scan easier, lesions are divided into three main groups: lesions of lung parenchyma, lesions of the heart and mediasti-num and lesions with origins of the protective tissues in the chest. Extrapulmonary lesions have various origins ranging from hard tissues like the bone, to soft tissues such as bone marrow or fatty tissue; they usu-ally present with diverse and sometimes misleading signs and symptoms. Knowledge about the radiologic semiolology of these instances helps to prevent mis-taking these lesions with lesions of pulmonary origin. Consequently timely and appropriate treatment can be provided. Here a study of five thousand chest radi-ographies of extrapulmonary lesions with primary diagnosis of pulmonary lesions is presented and the approach to diagnosis is discussed. According to the present study, 56% of extrapulmonary lesions are de-tectable by means of simple primary radiography and by considering radiologic semiology. We reached definite diagnosis by means of lung CT scan. Other lesions were diagnosed after performing biopsy or surgery.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1983-11-01

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

  14. Clinical implication of F-18 FDG PET/CT for differentiated thyroid cancer in patients with negative diagnostic iodine-123 scan and elevated thyroglobulin

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Seong-Jang [Department of Nuclear Medicine, Pusan National University Hospital, Busan (Korea, Republic of); Medical Research Institute, Pusan National University Hospital, Busan (Korea, Republic of)], E-mail: growthkim@daum.net; Lee, Tae Hong [Medical Research Institute, Pusan National University Hospital, Busan (Korea, Republic of); Department of Radiology, Pusan National University Hospital, Busan (Korea, Republic of); Kim, In-Ju; Kim, Yong-Ki [Department of Nuclear Medicine, Pusan National University Hospital, Busan (Korea, Republic of); Medical Research Institute, Pusan National University Hospital, Busan (Korea, Republic of)

    2009-04-15

    This study aims to investigate the usefulness of F-18 FDG PET/CT in differentiated thyroid cancer (DTC) with elevated serum thyroglobulin (Tg) but negative iodine-123 (I-123) scan. Methods: Twenty patients with histopathologically proven DTC, negative diagnostic I-123 scan, and elevated serum Tg levels were prospectively submitted to F-18 FDG PET/CT evaluation. The histopathologic findings consisted of 19 papillary thyroid cancers, 1 follicular thyroid cancer. Results: F-18 FDG PET/CT identified lesions in 18 out of 20 patients, giving a sensitivity of 90%. Thirteen of the 18 patients revealed limited loco-regional disease. Remaining 5 patients showed distant metastases, consisting of 4 patients with lung metastases and 1 patient with bone metastasis. Two patients revealed negative F-18 FDG PET/CT findings. Conclusion: F-18 FDG PET/CT is suitable for the detection and precise localization of loco-regional recurrences and distant metastases of DTC in patients with elevated serum Tg but negative I-123 whole body scan.

  15. Three-dimensional CT imaging with a helical scan on temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Honghan; Hiraishi, Kumiko; Uesugi, Yasuo; Sakakura, Atsushi; Yoshikawa, Shuji; Shimizu, Takaya; Sueyoshi, Kozo; Narabayashi, Isamu [Osaka Medical Coll., Takatsuki (Japan)

    1996-06-01

    To evaluate the usefulness of three-dimensional (3D) CT on the lesions of temporal bone, we studied 19 patients with disorders on the region of temporal bone by high speed helical CT. The results showed that 8 patients with congenital hearing disorder had deficiency of the auditory ossicles, 2 patients with chronic otitis media had deformity and shortness of the auditory ossicles, 4 patients with trauma had fracture of the temporal bone (1 patient was complicated by doubtful fracture of the incus), 5 patients (4 patients with acquired hearing disorder and 1 patient with otorrhea) had space-occupying lesions. 3-D helical CT could detect abnormal findings on all the patients and it was an important examination for the temporal bone. (author)

  16. Value of a step-up diagnosis plan: CRP and CT-scan to diagnose and manage postoperative complications after major abdominal surgery

    Directory of Open Access Journals (Sweden)

    Jennifer Straatman

    2014-12-01

    Full Text Available Postoperative complications frequently follow major abdominal surgery and are associated with increased morbidity and mortality. Early diagnosis and treatment of complications is associated with improved patient outcome. In this study we assessed the value of a step-up diagnosis plan by C-reactive protein and CT-scan (computed tomography-scan imaging for detection of postoperative complications following major abdominal surgery. An observational cohort study was conducted of 399 consecutive patients undergoing major abdominal surgery between January 2009 and January 2011. Indication for operation, type of surgery, postoperative morbidity, complications according to the Clavien-Dindo classification and mortality were recorded. Clinical parameters were recorded until 14 days postoperatively or until discharge. Regular C-reactive protein (CPR measurements in peripheral blood and on indication -enhanced CT-scans were performed. Eighty-three out of 399 (20.6 % patients developed a major complication in the postoperative course after a median of seven days (IQR 4-9 days. One hundred and thirty two patients received additional examination consisting of enhanced CT-scan imaging, and treatment by surgical reintervention or intensive care observation. CRP levels were significantly higher in patients with postoperative complications. On the second postoperative day CRP levels were on average 197.4 mg/L in the uncomplicated group, 220.9 mg/L in patients with a minor complication and 280.1 mg/L in patients with major complications (p < 0,001. CT-scan imaging showed a sensitivity of 91.7 % and specificity of 100 % in diagnosis of major complications. Based on clinical deterioration and the increase of CRP, an additional enhanced CT-scan offered clear discrimination between patients with major abdominal complications and uncomplicated patients. Adequate treatment could then be accomplished.

  17. Adhesion therapy for lung cancer with massive Pleural effusion (pleuritis carcinomatosa) adhesion therapy and evaluation by CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Sugiyama, Akira; Katayama, Motoyuki; Kokubo, Mitsuharu; Tateyama, Kenichirou [National Tohsei Hospital, Shimizu, Shizuoka (Japan)

    1996-06-01

    Ten patients with pleuritis carcinomatosa due to lung cancer accompanied by massive effusion were treated by tube drainage of effusion followed by instillation of MMC and OK-432 (adhesion therapy). Pleural effusion was controlled in all patients without recurrence but one showed reaccumulation 2 months later. Acute side effects of fever and chest pain were tolerable. The average hospital stay for patients receiving adhesion therapy alone was 34 days, versus 93 days for patients receiving tube drainage therapy and radiotherapy. The average survival time for 7 patients who died of this disease was 273 days. Serial CE-CT scans were useful to evaluate the stage of the disease and decide on therapeutic and follow-up policy. All cases had mediastinal metastasis (N2-3). On follow up CT scan, marked pleural thickening and varying degree of loss of lung volume were noticed. Individual cases with life expectancy several months are best managed by tube drainage and instillation of adhesion-inducing agents. (author)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-02-01

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

  19. Survey regarding the clinical practice of cardiac CT in Germany. Indications, scanning technique and reporting

    Energy Technology Data Exchange (ETDEWEB)

    Maurer, Marc H.; Hamm, B.; Dewey, M. [Inst. fuer Radiologie, Charite - Universitaetsmedizin Berlin (Germany)

    2009-12-15

    Purpose: to obtain an overview of the current clinical practice of cardiac computed tomography (CT) in Germany. Materials and methods: a 30-item question-naire was mailed to 149 providers of cardiac CT in Germany. The items asked about indications, scanning technique and reporting, data storage, and cost of the examination. Results: overall 45 questionnaires could be analyzed (30%). The majority of centers (76%, 34 of 45 centers) used CT scanners of the latest generation (at least 64 rows). The most common appropriate indications were exclusion of coronary artery disease (91%, 41/45), coronary anomalies (80%, 36/45), and follow-up after coronary artery bypass grafting (53%, 24/45). Each center examined on average 243 {+-} 310 patients in 2007 and the number of centers performing cardiac CT increased significantly in 2007 (p = 0.035) compared with the preceding year. Most used sublingual nitroglycerin (84%, 38/45; median of 2 sprays = 0.8 mg) and/or a beta blocker (86%, 39/44; median of 5 mg IV, median heart rate threshold: 70 beats/min). Many providers used ECG-triggered tube current modulation (65%, 29/44) and/or adjusted the tube current to the body mass index or body weight (63%, 28/44). A median slice thickness of 0.75 mm with a 0.5 mm increment and a 20 cm field-of-view was most commonly used. Source images in orthogonal planes (96%, 43/45), curved MPRs (93%, 42/45), and thin-slice MIPs (69%, 31/45) were used most frequently for interpretation. Extracardiac structures were also evaluated by 84% of the centers (38/45). The mean examination time was 16.2 min and reporting took an average of 28.8 min. (orig.)

  20. Reducing the throughput time of the diagnostic track involving CT scanning with computer simulation.

    Science.gov (United States)

    van Lent, Wineke A M; Deetman, Joost W; Teertstra, H Jelle; Muller, Sara H; Hans, Erwin W; van Harten, Wim H

    2012-11-01

    To examine the use of computer simulation to reduce the time between the CT request and the consult in which the CT report is discussed (diagnostic track) while restricting idle time and overtime. After a pre implementation analysis in our case study hospital, by computer simulation three scenarios were evaluated on access time, overtime and idle time of the CT; after implementation these same aspects were evaluated again. Effects on throughput time were measured for outpatient short-term and urgent requests only. The pre implementation analysis showed an average CT access time of 9.8 operating days and an average diagnostic track of 14.5 operating days. Based on the outcomes of the simulation, management changed the capacity for the different patient groups to facilitate a diagnostic track of 10 operating days, with a CT access time of 7 days. After the implementation of changes, the average diagnostic track duration was 12.6 days with an average CT access time of 7.3 days. The fraction of patients with a total throughput time within 10 days increased from 29% to 44% while the utilization remained equal with 82%, the idle time increased by 11% and the overtime decreased by 82%. The fraction of patients that completed the diagnostic track within 10 days improved with 52%. Computer simulation proved useful for studying the effects of proposed scenarios in radiology management. Besides the tangible effects, the simulation increased the awareness that optimizing capacity allocation can reduce access times. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  1. Multiphase CT scanning and different intravenous contrast media concentrations in combined F-18-FDG PET/CT: Effect on quantitative and clinical assessment

    Energy Technology Data Exchange (ETDEWEB)

    Rebiere, Marilou, E-mail: Marilou.Rebiere@rwth-aachen.de [Department of Nuclear Medicine, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52057 Aachen (Germany); Verburg, Frederik A., E-mail: fverburg@ukaachen.de [Department of Nuclear Medicine, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52057 Aachen (Germany); Department of Nuclear Medicine, Maastricht University Medical Center, P. Debeylaan 25, 6202 AZ Maastricht (Netherlands); Palmowski, Moritz, E-mail: mpalmowski@ukaachen.de [Department of Nuclear Medicine, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52057 Aachen (Germany); Department of Radiology, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52057 Aachen (Germany); Department of Experimental Molecular Imaging, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52057 Aachen (Germany); Krohn, Thomas, E-mail: tkrohn@ukaachen.de [Department of Nuclear Medicine, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52057 Aachen (Germany); Pietsch, Hubertus, E-mail: hubertus.pietsch@bayer.com [Contrast Media Research, Bayer Pharma AG, Muellerstr. 178, 13353 Berlin (Germany); Kuhl, Christiane K., E-mail: ckuhl@ukaachen.de [Department of Radiology, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52057 Aachen (Germany); Mottaghy, Felix M., E-mail: fmottaghy@ukaachen.de [Department of Nuclear Medicine, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52057 Aachen (Germany); Department of Nuclear Medicine, Maastricht University Medical Center, P. Debeylaan 25, 6202 AZ Maastricht (Netherlands); Behrendt, Florian F., E-mail: fbehrendt@ukaachen.de [Department of Nuclear Medicine, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52057 Aachen (Germany)

    2012-08-15

    Purpose: To evaluate the influence of multiphase CT scanning and different intravenous contrast media on contrast enhancement, attenuation correction and image quality in combined PET/CT. Material and methods: 140 patients were prospectively enrolled for F-18-FDG-PET/CT including a low-dose unenhanced, arterial and venous contrast enhanced CT. The first (second) 70 patients, received contrast medium with 370 (300) mg iodine/ml. The iodine delivery rate (1.3 mg/s) and total iodine load (44.4 g) were identical for both groups. Contrast enhancement and maximum and mean standardized FDG uptake values (SUVmax and SUVmean) were determined for the un-enhanced, arterial and venous PET/CT at multiple anatomic sites and PET reconstructions were visually evaluated. Results: Arterial contrast enhancement was significantly higher for the 300 mg/ml contrast medium compared to 370 mg I/ml at all anatomic sites. Venous enhancement was not different between the two contrast media. SUVmean and SUVmax were significantly higher for the contrast enhanced compared to the non-enhanced PET/CT at all anatomic sites (all P < 0.001). Tracer uptake was significantly higher in the arterial than in the venous PET/CT in the arteries using both contrast media (all P < 0.001). No differences in tracer uptake were found between the contrast media (all P > 0.05). Visual assessment revealed no relevant differences between the different PET reconstructions. Conclusions: There is no relevant qualitative influence on the PET scan from the use of different intravenous contrast media in its various phases in combined multiphase PET/CT. For quantitative analysis of tracer uptake it is required to use an identical PET/CT protocol.

  2. Moving metal artifact reduction in cone-beam CT scans with implanted cylindrical gold markers

    Energy Technology Data Exchange (ETDEWEB)

    Toftegaard, Jakob, E-mail: jaktofte@rm.dk; Fledelius, Walther; Worm, Esben S.; Poulsen, Per R. [Department of Oncology, Aarhus University Hospital, Aarhus 8000 (Denmark); Seghers, Dieter; Huber, Michael; Brehm, Marcus [Varian Medical Systems, Imaging Laboratory GmbH, Baden-Daettwil 5405 (Switzerland); Elstrøm, Ulrik V. [Department of Medical Physics, Aarhus University Hospital, Aarhus 8000 (Denmark)

    2014-12-15

    Purpose: Implanted gold markers for image-guided radiotherapy lead to streaking artifacts in cone-beam CT (CBCT) scans. Several methods for metal artifact reduction (MAR) have been published, but they all fail in scans with large motion. Here the authors propose and investigate a method for automatic moving metal artifact reduction (MMAR) in CBCT scans with cylindrical gold markers. Methods: The MMAR CBCT reconstruction method has six steps. (1) Automatic segmentation of the cylindrical markers in the CBCT projections. (2) Removal of each marker in the projections by replacing the pixels within a masked area with interpolated values. (3) Reconstruction of a marker-free CBCT volume from the manipulated CBCT projections. (4) Reconstruction of a standard CBCT volume with metal artifacts from the original CBCT projections. (5) Estimation of the three-dimensional (3D) trajectory during CBCT acquisition for each marker based on the segmentation in Step 1, and identification of the smallest ellipsoidal volume that encompasses 95% of the visited 3D positions. (6) Generation of the final MMAR CBCT reconstruction from the marker-free CBCT volume of Step 3 by replacing the voxels in the 95% ellipsoid with the corresponding voxels of the standard CBCT volume of Step 4. The MMAR reconstruction was performed retrospectively using a half-fan CBCT scan for 29 consecutive stereotactic body radiation therapy patients with 2–3 gold markers implanted in the liver. The metal artifacts of the MMAR reconstructions were scored and compared with a standard MAR reconstruction by counting the streaks and by calculating the standard deviation of the Hounsfield units in a region around each marker. Results: The markers were found with the same autosegmentation settings in 27 CBCT scans, while two scans needed slightly changed settings to find all markers automatically in Step 1 of the MMAR method. MMAR resulted in 15 scans with no streaking artifacts, 11 scans with 1–4 streaks, and 3 scans

  3. A contrast enhancement and scanning techniques for CT angiography of head and neck. One phase injection method for simultaneous imaging of vessels and tumor

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Yasuhiko; Indo, Hiroko; Noikura, Takenori [Kagoshima Univ. (Japan). Dental School

    1999-09-01

    We report on a method of CT-Angiography useful for examining lesion of the head and neck using three-dimensional images and measured CT value. This study focused on some of the important blood vessels in the head and neck. The aim of this method was to obtain high-contrast enhancement for both vessels and tumors at same time. A total amount of 100 ml nonionic contrast media (Omnipaque 240, 240 mg iodine per milliliter, Daiichi seiyaku, Tokyo, Japan) was injected intravenously with a flow of 1.5 ml/sec. Spiral scans, 24 rotations with 24 seconds, were started at a time when remaining amount of contrast media had become 30 to 20 ml. All CT scans were performed using double speed spiral scan technique with a slice thickness of 2 to 3 mm and table speeds from 3 to 5 mm/rotation. The patients populations consisted of 9 men and 6 women who ranged in age from 37 to 85 years. Sixteen CT-angiography were performed according to this method. Mean CT values of major blood vessels were measured in order to find out threshold at the level of submandibular gland in 13 examinations for 12 subjects. Important vessels like the common, internal, and the external artery, internal and external jugular vein were clearly visible in all subjects. Three dimensional images of these vessels could also be reconstructed for 15 of the subjects. Mean CT values were 211 Hounsfield units (HU) and 209 HU for the right and left internal carotid artery, respectively, and 204 HU and 206 HU for the right and left external carotid artery, respectively. Mean CT values for right and left internal jugular vein were 195 HU and 194 HU respectively. Measured CT values at each important blood vessels showed this method could yields acceptable enhancements. Good enhancement effect of tumor and blood vessels in the same scan seems to be mutually incompatible. One very important trade-off is the early enhancement effect at blood vessels versus the late enhancement effect at tumors. The other important trade

  4. 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.

  5. 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

    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 r

  6. CT perfusion scanning of the brain in stroke and beyond; Kranielle CT-Perfusion. Beim Schlaganfall und ueber den Schlaganfall hinaus

    Energy Technology Data Exchange (ETDEWEB)

    Riedel, Christian [UKSH Campus Kiel (Germany). Inst. fuer Neuroradiologie

    2011-06-15

    CT perfusion scanning (CTP) allows for quantitative analysis of cerebral blood flow (CBF) and cerebral blood volume (CBV). Until recently, it was only possible to study brain perfusion parameters in a small stack of CT-slices close to the skull base. With the introduction of multidetector CT scanners with 64 and more detector rows it has become possible to assess perfusion of the entire brain. An optimal choice of scanning parameters like the new 'shuttle'-technique combined with a well adapted regimen for contrast administration is required to guarantee reliable perfusion measurements while still keeping the X-ray dose absorbed by the patient at a minimum. With these techniques, CTP is not only an important modality in the work-up of patients suffering from acute ischemic stroke but can also be valuable in other emergency situations such as in prolonged epileptic seizures or to monitor patients with subacute subarachnoid hemorrhage. (orig.)

  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. Evaluation of thin section CT scanning in the prone position of metastatic axillary lymphnodes for breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Hata, Yasuhiro; Ogawa, Yasuhiro; Nishioka, Akihito; Inomata, Taisuke; Yoshida, Shoji; Toki, Taiichi [Kochi Medical School, Nangoku (Japan)

    1996-12-01

    A retrospective study was performed to determine whether thin section CT scanning in the prone position of the breast and the axilla yield useful information regarding the status of axillary lymph nodes in patients with breast cancer. Thirty-six patients with breast carcinomas were scanned preoperatively from the supraclavicular regions to the breast in the prone position with 5 mm sections. Axillary lymph nodes measuring {>=}5 mm on the short axis were considered abnormal. Correlation with axillary dissection was obtained in all patients, giving a positive predictive value for axillary metastases of 83.3%, with 88.2% sensitivity, 84.2% specificity, and 88.8% negative predictive value. We concluded that thin section CT scan in the prone position was an accurate predictor of axillary lymph node involvement. We made a phantom with lymph node swelling to evaluate whether CT scanning with 5 mm sections was necessary for detecting 5 mm swollen lymph nodes. We scanned the phantom with 5 mm and 10 mm sections. Twelve radiologists counted the swollen lymph nodes on 5 mm section images and 10 mm section images of the phantom. The average number of miscounts was 1.1 (miscount rate 6.8%) on 5 mm section and 2.8 (15%) on 10 mm sections. We conclued that 5 mm section CT scanning is superior for detecting 5 mm lymph nodes. (author)

  9. Making sense of large data sets without annotations: analyzing age-related correlations from lung CT scans

    Science.gov (United States)

    Dicente Cid, Yashin; Mamonov, Artem; Beers, Andrew; Thomas, Armin; Kovalev, Vassili; Kalpathy-Cramer, Jayashree; Müller, Henning

    2017-03-01

    The analysis of large data sets can help to gain knowledge about specific organs or on specific diseases, just as big data analysis does in many non-medical areas. This article aims to gain information from 3D volumes, so the visual content of lung CT scans of a large number of patients. In the case of the described data set, only little annotation is available on the patients that were all part of an ongoing screening program and besides age and gender no information on the patient and the findings was available for this work. This is a scenario that can happen regularly as image data sets are produced and become available in increasingly large quantities but manual annotations are often not available and also clinical data such as text reports are often harder to share. We extracted a set of visual features from 12,414 CT scans of 9,348 patients that had CT scans of the lung taken in the context of a national lung screening program in Belarus. Lung fields were segmented by two segmentation algorithms and only cases where both algorithms were able to find left and right lung and had a Dice coefficient above 0.95 were analyzed. This assures that only segmentations of good quality were used to extract features of the lung. Patients ranged in age from 0 to 106 years. Data analysis shows that age can be predicted with a fairly high accuracy for persons under 15 years. Relatively good results were also obtained between 30 and 65 years where a steady trend is seen. For young adults and older people the results are not as good as variability is very high in these groups. Several visualizations of the data show the evolution patters of the lung texture, size and density with age. The experiments allow learning the evolution of the lung and the gained results show that even with limited metadata we can extract interesting information from large-scale visual data. These age-related changes (for example of the lung volume, the density histogram of the tissue) can also be

  10. Does early ED CT scanning of afebrile patients with first episodes of acute pancreatitis ever change management?

    Science.gov (United States)

    Dachs, Robert J; Sullivan, Luke; Shanmugathasan, Preshanthini

    2015-06-01

    Rising utilization of computed tomography (CT) imaging early in the course of acute pancreatitis (AP) has been recently reported. However, radiographic demonstration of the degree of necrosis or the presence of complications is not fully apparent within the first days of an acute attack. The objective of this study was to examine if CT scanning early in the course of disease (<48 h of symptoms) in afebrile patients with an emergency department (ED) diagnosis of first episode of AP revealed any unanticipated pathology that altered clinical management. A retrospective chart review of all adult patients with a first episode of AP without fever admitted to the medical ward through the ED of our community hospital from January 1, 2011 to May 31, 2012 was performed. In cases in which CT scans were performed, the record was reviewed to determine if any unexpected findings were uncovered or if patient care was altered by the CT report. Two hundred forty-eight patients were admitted with an ED diagnosis of AP; 26.2 % (n = 65) met inclusion criteria; 70.8 % (n = 46) received a CT scan within 48 h of symptom onset. No patient that underwent CT scanning had an unexpected finding (95 % CI, 0.923-1.0). Our results demonstrate that afebrile patients with first episodes of AP do not benefit from early abdominal CT imaging. These results support the ACR Appropriateness Criteria recommendation that CT is not indicated in the first 48 h after symptom onset in unequivocal cases of AP.

  11. A case of catastrophic antiphospholipid syndrome, which presented an acute interstitial pneumonia-like image on chest CT scan.

    Science.gov (United States)

    Kameda, Tomohiro; Dobashi, Hiroaki; Susaki, Kentaro; Danjo, Junichi; Nakashima, Shusaku; Shimada, Hiromi; Izumikawa, Miharu; Takeuchi, Yohei; Mitsunaka, Hiroki; Bandoh, Shuji; Imataki, Osamu; Nose, Masato; Matsunaga, Takuya

    2015-01-01

    We report the case of catastrophic antiphospholipid syndrome (CAPS) complicated with mixed connective tissue disease (MCTD). A female patient was diagnosed with acute interstitial pneumonia (AIP) with MCTD by chest CT scan. Corticosteroid therapy was refractory for lung involvement, and she died due to acute respiratory failure. The autopsy revealed that AIP was compatible with lung involvement of CAPS. We therefore suggest that chest CT might reveal AIP-like findings in CAPS patients whose condition is complicated with pulmonary manifestations.

  12. A study of the short- to long-phantom dose ratios for CT scanning without table translation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xinhua; Zhang, Da; Liu, Bob, E-mail: bliu7@mgh.harvard.edu [Division of Diagnostic Imaging Physics, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114 and Webster Center for Advanced Research and Education in Radiation, Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States); Yang, Jie [Pinnacle Health - Fox Chase Regional Cancer Center, Harrisburg, Pennsylvania 17109 (United States)

    2014-09-15

    Purpose: For CT scanning in the stationary-table modes, AAPM Task Group 111 proposed to measure the midpoint dose on the central and peripheral axes of sufficiently long phantoms. Currently, a long cylindrical phantom is usually not available in many clinical facilities. The use of a long phantom is also challenging because of the heavy weight. In order to shed light on assessing the midpoint dose in CT scanning without table movement, the authors present a study of the short- to long-phantom dose ratios, and perform a cross-comparison of CT dose ratios on different scanner models. Methods: The authors performed Geant4-based Monte Carlo simulations with a clinical CT scanner (Somatom Definition dual source CT, Siemens Healthcare), and modeled dosimetry measurements using a 0.6 cm{sup 3} Farmer type chamber and a 10-cm long pencil ion chamber. The short (15 cm) to long (90 cm) phantom dose ratios were computed for two PMMA diameters (16 and 32 cm), two phantom axes (the center and the periphery), and a range of beam apertures (3–25 cm). The results were compared with the published data of previous studies with other multiple detector CT (MDCT) scanners and cone beam CT (CBCT) scanners. Results: The short- to long-phantom dose ratios changed with beam apertures but were insensitive to beam qualities (80–140 kV, the head and body bowtie filters) and MDCT and CBCT scanner models. Conclusions: The short- to long-phantom dose ratios enable medical physicists to make dosimetry measurements using the standard CT dosimetry phantoms and a Farmer chamber or a 10 cm long pencil chamber, and to assess the midpoint dose in long phantoms. This method provides an effective approach for the dosimetry of CBCT scanning in the stationary-table modes, and is useful for perfusion and interventional CT.

  13. Age estimation by 3D CT-scans of the Borremose Woman, a Danish bog body

    DEFF Research Database (Denmark)

    Villa, Chiara; Møller Rasmussen, Maria; Lynnerup, Niels

    2011-01-01

    been visualized from CT-scans using the Mimics software from Materialise. Extensive manual editing was necessary, as is common with bog bodies, since the bones were severely degraded and the ordinary range of Hounsfield Units (HU), used for clinical work, is not suitable. Only the cranium, the left...... ribs and the right auricular surface were 3D visualized. Based on these visualizations, the age was estimated by applying macroscopic methods routinely used for skeletal remains: the cranial sutures closure (Meindl & Lovejoy 1985), the sternal rib end (Iscan & Loth 1986) and the auricular surface...... was 16 to 24 years. Many problems had to be addressed. First of all, the degradation of the skeletal tissue does not allow a complete visualization: the bones are demineralized because of the acidic bog environment. Another problem is the subjectivity that can arise during manual editing, especially...

  14. 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.

  15. Brain CT-scan in acute stroke patients: silent infarcts and relation to outcome.

    Science.gov (United States)

    Corea, Francesco; Tambasco, Nicola; Luccioli, Roberto; Ciorba, Ettore; Parnetti, Lucilla; Gallai, Virgilio

    2002-01-01

    Silent infarcts (SIs) are common findings in stroke patients, but their clinical significance remains controversial. Aim of this study was to evaluate the prevalence of SI in consecutive stroke patients, characteristics, associated factors, and influence on in-hospital mortality. The population consisted of 191 patients, consecutively admitted for an acute stroke. Of 191 patients, 74 had SI on CT-scan. Silent infarcts were often multiple, right sided, lacunar. We found SI more frequently in older patients, smokers, with an ischemic stroke having small vessel disease as presumed cause. In our study SI were associated with ageing, smoke habit and lacunar stroke. Silent infarcts size influenced the rate of in-hospital mortality.

  16. CT scanning carcases has no detrimental effect on the colour stability of M. longissimus dorsi from beef and sheep.

    Science.gov (United States)

    Jose, C G; Pethick, D W; Jacob, R H; Gardner, G E

    2009-01-01

    This study investigated the effect of computerised tomography imaging (CT scan), for carcase composition determination, on the oxy/metmyoglobin ratio, hue and L(∗), a(∗) and b(∗) scores of M. longissimus dorsi from both beef and lamb. Beef and lamb M. longissimus dorsi were divided into four proportions and randomly allocated to one of the following treatments; CT 30 day aged; CT fresh; control 30 day aged; control fresh. Colour measurements were made over a 96h retail display period. CT scan had little effect on the colour of both lamb and beef across all colour parameters. There was a small negative affect observed in CT aged samples (PCT. Aged M. longissimus dorsi clearly had a worse colour stability than the fresh packaged samples, while beef was a lot more colour stable than lamb. It appears that CT scan for the purpose of body composition determination will not have any commercially relevant impact on colour stability of both beef and lamb.

  17. 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.

  18. CT-scans of cochlear implant patients with characteristics of Pendred syndrome.

    Science.gov (United States)

    Roesch, Sebastian; Moser, Gerhard; Rasp, Gerd; Tóth, Miklós

    2013-01-01

    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. We screened CT scans of 75 cochlear implant patients for EVA and MM. 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. 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. © 2014 S. Karger AG, Basel.

  19. Successful surgical removal of the large retrocardiac mass. The usefulness of CT scan and intraoperative echocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Minoru; Abe, Toshio; Murase, Mitsuya; Nogaki, Hideitsu; Takeuchi, Eiji (Nagoya Univ. (Japan). Faculty of Medicine)

    1983-04-01

    Computed tomography had proved useful in identifying cardiac lesion, especially space taking lesion. A 53-year-old man, who had open mitral commissurotomy eight years ago, has been regarded as the patient with an unresectable tumor of the left ventricle by echocardiography during about five years before this operation. However, the finding of cardiac CT scan in this patient led to excision of the mass. The patient was operated on through the left fifth intercostal space incision without extracorporeal circulation. The pericardium was densely adherent to the heart. We could not tell the border between the mass and the myocardium. Therefore, it was too difficult to incise the mass without injury to the myocardium or the coronary artery. After embarrassment, intraoperative echocardiography was performed. Intraoperative echocardiography demonstrated the size and the location of the mass, and its relation to the myocardiom, which resulted in successful removal of the mass. The removed mass was old hematoma of 300 gr in weight. In this paper, the usefulness of CT and intraoperative echocardiograpy was described and the origin of this hematoma was discussed.

  20. What is a reliable CT scan for diagnosing splenosis under emergency conditions?

    Institute of Scientific and Technical Information of China (English)

    Francesco Giuseppe Garaci; Michele Grande; Massimo Villa; Stefano Mancino; Daniel Konda; Grazia Maria Attinà; Gabriele Galatà; Giovanni Simonetti

    2009-01-01

    Splenosis is a condition in which splenic tissue is present in a non-anatomical position. Implants of splenic tissue can mimic neoplasms and only specific examinations can confirm the correct diagnosis. Here we report a case of a 23-year-old male patient with a history of surgical splenectomy during childhood after trauma. He was admitted to the emergency department with acute bowel obstruction. An abdominalpelvic computed tomography (CT) scan revealed small bowel obstruction and the presence of two rounded, solid masses located in the rectal-vescical pouch. Quantitative analyses of the different density values in the arterial phase and early portal venous phase demonstrated that these lesions were highly vascularised (92 and 97 Hounsfield Units, respectively). The hypothesis of an ectopic splenic mass was made after evaluation of the CT images and clinical history. The acute bowel obstruction caused by adhesive intestinal syndrome was resolved by surgical adhesiolysis. The smallest mass adherent to the rectum was removed. Histopathologic examination confirmed the benign nature of the lesion, which consisted of splenic tissue.

  1. A comparative study of the diagnostic accuracy on Waters view with CT scan in detecting midface fractures

    Directory of Open Access Journals (Sweden)

    Panjnoush M.

    2006-08-01

    Full Text Available Background and Aim: In recent years, CT scan has become available as an alternative to conventional radiography. To date, the utility of Waters view in detecting midface fractures has been rarely evaluated. The aim of this study was to compare the diagnostic accuracy and reliability of Waters radiography with CT scan in detecting midface fractures. Materials and Methods: In this tests evaluation study, waters view and CT scan were performed for 42 patients with midface fracture admitted to maxillofacial surgery department of Shariati hospital. All images were observed and interpreted by an oral and maxillofacial radiologist and an oral and maxillofacial surgeon. Sensitivity, specificity and reliability for Waters view in detecting midface fractures were assessed by Cohen’s kappa test. Results: Sensitivity and specificity for Waters view in detection of midface fratures by the radiologist were 31.79% and 95.35% and by the surgeon were 29.59% and 93.75% respectively. The highest reliability in CT scan and Waters view (in nasal fractures by the radiologist was 66.67% and was 58.33% by the surgeon in buttress of zygoma. The highest agreement rate between the radiologist and the surgeon for CT scan was in zygomatic arch (78.95% and for Waters view was in nasal fracture (62.5%. Conclusion: Based on the results of this study, the specificity of Waters view is sufficient to diagnose fractures of lateral orbital wall, infraorbital rim, orbital floor, zygomatic arch, frontozygomatic suture, lateral wall of maxillary sinus and Lefort II fracture. The specificity is not sufficient to diagnose fractures of medial orbital wall and anterior, posterior and medial wall of maxillary sinus. Detection of these midface fractures needs other conventional radiographies or CT scan.

  2. 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.

  3. 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.

  4. Heart region segmentation from low-dose CT scans: an anatomy based approach

    Science.gov (United States)

    Reeves, Anthony P.; Biancardi, Alberto M.; Yankelevitz, David F.; Cham, Matthew D.; Henschke, Claudia I.

    2012-02-01

    Cardiovascular disease is a leading cause of death in developed countries. The concurrent detection of heart diseases during low-dose whole-lung CT scans (LDCT), typically performed as part of a screening protocol, hinges on the accurate quantification of coronary calcification. The creation of fully automated methods is ideal as complete manual evaluation is imprecise, operator dependent, time consuming and thus costly. The technical challenges posed by LDCT scans in this context are mainly twofold. First, there is a high level image noise arising from the low radiation dose technique. Additionally, there is a variable amount of cardiac motion blurring due to the lack of electrocardiographic gating and the fact that heart rates differ between human subjects. As a consequence, the reliable segmentation of the heart, the first stage toward the implementation of morphologic heart abnormality detection, is also quite challenging. An automated computer method based on a sequential labeling of major organs and determination of anatomical landmarks has been evaluated on a public database of LDCT images. The novel algorithm builds from a robust segmentation of the bones and airways and embodies a stepwise refinement starting at the top of the lungs where image noise is at its lowest and where the carina provides a good calibration landmark. The segmentation is completed at the inferior wall of the heart where extensive image noise is accommodated. This method is based on the geometry of human anatomy and does not involve training through manual markings. Using visual inspection by an expert reader as a gold standard, the algorithm achieved successful heart and major vessel segmentation in 42 of 45 low-dose CT images. In the 3 remaining cases, the cardiac base was over segmented due to incorrect hemidiaphragm localization.

  5. The value of Weight-Bearing CT scan in the evaluation of subtalar distraction bone block arthrodesis: Case report.

    Science.gov (United States)

    Welck, M J; Myerson, M S

    2015-12-01

    Subtalar distraction arthrodesis is performed in certain situations where there is loss of subtalar height, reduced talar declination and evidence of anterior tibiotalar impingement. Standard evaluation includes the assessment of the lateral talocalcaneal angle, calcaneal pitch, talocalcaneal height and talar declination angle on a weight bearing lateral radiograph. We present a case of erosive valgus subtalar osteoarthritis with subtalar collapse managed with a subtalar distraction arthrodesis. A weight bearing CT (WB-CT) scan was used in the assessment. The value of WB-CT for this indication is discussed, along with a discussion on surgical technique, complications and future directions. Copyright © 2015 European Foot and Ankle Society. All rights reserved.

  6. Renal varices. Diagnosis with CT scan and treatment with embolization; Varices renales. Deagnostic tomodensitometrique et traitement par embolisation

    Energy Technology Data Exchange (ETDEWEB)

    Lenoir, S.; Strauss, Ch.; Fontanelle, L.; Bouzar, N.; Veillon, B.; Vallancien, G.; Palou, R. [Institut Mutualiste Montsouris, 75 - Paris (France)

    1997-09-01

    Two cases of recurrent macroscopic Hematuria in which the diagnosis of left renal vein varices was suggested on CT are described. Bloody efflux was seen from the left ureteric orifice. On CT scans, tubulated contrast-enhanced densities in left perirenal fat were seen. Selective renal angiography was normal. Selective left renal phlebography demonstrated intra and perirenal varices. In the two cases, embolization with metallic coil was successfully performed during left renal phlebography, to stop renal varices flux. Diagnostic and therapeutic modalities of renal varices are discussed with predominant place for CT and phlebography. (authors). 13 refs.

  7. 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

    Background. Accurate stopping power estimation is crucial for treatment planning in proton therapy, and the uncertainties in stopping power are currently the largest contributor to the employed dose margins. Dual energy x-ray computed tomography (CT) (clinically available) and proton CT (in...

  8. Are positron emission tomography-computed tomography (PET-CT) scans useful in preoperative assessment of patients with peritoneal disease before cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC)?

    Science.gov (United States)

    Wang, Weining; Tan, Grace Hwei Ching; Chia, Claramae Shulyn; Skanthakumar, Thakshayeni; Soo, Khee Chee; Teo, Melissa Ching Ching

    2017-08-31

    CRS and HIPEC confer survival benefit in selected patients with peritoneal metatases (PM). Accurate preoperative assessment of disease burden and exclusion of distant metastases are crucial in selecting the appropriate patient. We evaluate the utility of PET-CT scans in comparison with CT and MRI scans in patients considered for CRS and HIPEC. Data were retrospectively collected from patients who had been discussed for CRS and HIPEC between January 2011 and December 2015, at our institutional multidisciplinary tumour board. Patients who underwent PET-CT scan were included. Results of PET-CT were compared against traditional imaging. Patient and tumour factors were analysed to identify those who were most likely to benefit from PET imaging. Four hundred and seven patients were considered for CRS and HIPEC. PET-CT was performed for 128(31.4%) patients: being the only imaging modality in 37 and used as an adjunct in 91. In the latter group, it was not beneficial in 58 patients as it provided no additional information (n = 33) or showed lesions of minimal FDG uptake (n = 25). In 33 patients, PET-CT provided definitive answers for indeterminate lesions seen on CT and MRI, confirmed the diagnosis of peritoneal disease in 10 patients (30.3%), identified extra-peritoneal disease and/or nodal metastases in 15 (45.5%) and excluded peritoneal disease in 8 (24.2%). The usefulness of PET-CT was predicted by tumour histology (p = .009), with non-mucinous tumours benefitting the most. Our results suggest that PET-CT can be used as an adjunct to CT and/or MRI scans, when lesions on the CT/MRI scans are indeterminate, and that it is most useful in patients with non-mucinous tumours.

  9. 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.

  10. The application of metal artifact reduction (MAR) in CT scans for radiation oncology by monoenergetic extrapolation with a DECT scanner

    Energy Technology Data Exchange (ETDEWEB)

    Schwahofer, Andrea [German Cancer Research Center, Heidelberg (Germany). Dept. of Medical Physics in Radiation Oncology; Clinical Center Vivantes, Neukoelln (Germany). Dept. of Radiotherapy and Oncology; Baer, Esther [German Cancer Research Center, Heidelberg (Germany). Dept. of Medical Physics in Radiation Oncology; Kuchenbecker, Stefan; Kachelriess, Marc [German Cancer Research Center, Heidelberg (Germany). Dept. of Medical Physics in Radiology; Grossmann, J. Guenter [German Cancer Research Center, Heidelberg (Germany). Dept. of Medical Physics in Radiation Oncology; Ortenau Klinikum Offenburg-Gengenbach (Germany). Dept. of Radiooncology; Sterzing, Florian [Heidelberg Univ. (Germany). Dept. of Radiation Oncology; German Cancer Research Center, Heidelberg (Germany). Dept. of Radiotherapy

    2015-07-01

    Metal artifacts in computed tomography CT images are one of the main problems in radiation oncology as they introduce uncertainties to target and organ at risk delineation as well as dose calculation. This study is devoted to metal artifact reduction (MAR) based on the monoenergetic extrapolation of a dual energy CT (DECT) dataset. In a phantom study the CT artifacts caused by metals with different densities: aluminum (ρ{sub Al} = 2.7 g/cm{sup 3}), titanium (ρ{sub Ti} = 4.5 g/cm{sup 3}), steel (ρ{sub steel} = 7.9 g/cm{sup 3}) and tungsten (ρ{sub W} = 19.3 g/cm{sup 3}) have been investigated. Data were collected using a clinical dual source dual energy CT (DECT) scanner (Siemens Sector Healthcare, Forchheim, Germany) with tube voltages of 100 kV and 140 kV (Sn). For each tube voltage the data set in a given volume was reconstructed. Based on these two data sets a voxel by voxel linear combination was performed to obtain the monoenergetic data sets. The results were evaluated regarding the optical properties of the images as well as the CT values (HU) and the dosimetric consequences in computed treatment plans. A data set without metal substitute served as the reference. Also, a head and neck patient with dental fillings (amalgam ρ = 10 g/cm{sup 3}) was scanned with a single energy CT (SECT) protocol and a DECT protocol. The monoenergetic extrapolation was performed as described above and evaluated in the same way. Visual assessment of all data shows minor reductions of artifacts in the images with aluminum and titanium at a monoenergy of 105 keV. As expected, the higher the densities the more distinctive are the artifacts. For metals with higher densities such as steel or tungsten, no artifact reduction has been achieved. Likewise in the CT values, no improvement by use of the monoenergetic extrapolation can be detected. The dose was evaluated at a point 7 cm behind the isocenter of a static field. Small improvements (around 1%) can be seen with 105 ke

  11. The application of metal artifact reduction (MAR) in CT scans for radiation oncology by monoenergetic extrapolation with a DECT scanner.

    Science.gov (United States)

    Schwahofer, Andrea; Bär, Esther; Kuchenbecker, Stefan; Grossmann, J Günter; Kachelrieß, Marc; Sterzing, Florian

    2015-12-01

    Metal artifacts in computed tomography CT images are one of the main problems in radiation oncology as they introduce uncertainties to target and organ at risk delineation as well as dose calculation. This study is devoted to metal artifact reduction (MAR) based on the monoenergetic extrapolation of a dual energy CT (DECT) dataset. In a phantom study the CT artifacts caused by metals with different densities: aluminum (ρ Al=2.7 g/cm(3)), titanium (ρ Ti=4.5 g/cm(3)), steel (ρ steel=7.9 g/cm(3)) and tungsten (ρ W=19.3g/cm(3)) have been investigated. Data were collected using a clinical dual source dual energy CT (DECT) scanner (Siemens Sector Healthcare, Forchheim, Germany) with tube voltages of 100 kV and 140 kV(Sn). For each tube voltage the data set in a given volume was reconstructed. Based on these two data sets a voxel by voxel linear combination was performed to obtain the monoenergetic data sets. The results were evaluated regarding the optical properties of the images as well as the CT values (HU) and the dosimetric consequences in computed treatment plans. A data set without metal substitute served as the reference. Also, a head and neck patient with dental fillings (amalgam ρ=10 g/cm(3)) was scanned with a single energy CT (SECT) protocol and a DECT protocol. The monoenergetic extrapolation was performed as described above and evaluated in the same way. Visual assessment of all data shows minor reductions of artifacts in the images with aluminum and titanium at a monoenergy of 105 keV. As expected, the higher the densities the more distinctive are the artifacts. For metals with higher densities such as steel or tungsten, no artifact reduction has been achieved. Likewise in the CT values, no improvement by use of the monoenergetic extrapolation can be detected. The dose was evaluated at a point 7 cm behind the isocenter of a static field. Small improvements (around 1%) can be seen with 105 keV. However, the dose uncertainty remains of the order of 10

  12. {sup 11}C-Choline PET/CT detects the site of relapse in the majority of prostate cancer patients showing biochemical recurrence after EBRT

    Energy Technology Data Exchange (ETDEWEB)

    Ceci, Francesco; Graziani, Tiziano; Lodi, Filippo; Fanti, Stefano [University of Bologna, Service of Nuclear Medicine, Policlinico S. Orsola Malpighi, Bologna (Italy); Castellucci, Paolo [University of Bologna, Service of Nuclear Medicine, Policlinico S. Orsola Malpighi, Bologna (Italy); Azienda Ospedaliero-Unversitaria di Bologna Policlinico Sant' Orsola-Malpighi, UO di Medicina Nucleare, PAD. 30, Bologna (Italy); Schiavina, Riccardo; Brunocilla, Eugenio; Martorana, Giuseppe [University of Bologna, Department of Urology, Policlinico S. Orsola Malpighi, Bologna (Italy); Mazzarotto, Renzo; Ntreta, Maria [University of Bologna, Service of Radiotherapy, Policlinico S. Orsola Malpighi, Bologna (Italy)

    2014-05-15

    The aim of this retrospective study was to evaluate the usefulness and the detection rate of {sup 11}C-choline PET/CT in a population of patients with prostate cancer (PC), exclusively treated with external beam radiotherapy (EBRT) as primary treatment, who showed biochemical relapse. We enrolled 140 patients showing a serum PSA level >2 ng/mL (mean 8.6 ng/mL, median 5 ng/mL, range 2 - 60 ng/mL). All patients had been treated with EBRT to the prostate gland and prostatic fossa with doses ranging from 70 to 76 Gy in low-risk patients (T1/T2 and/or serum PSA <10 ng/mL) and escalating to >76 Gy (range 76 - 81 Gy) in high-risk patients (T3/T4 and/or serum PSA >10 ng/mL). Of the 140 patients, 53 were receiving androgen deprivation therapy at the time of the scan. All positive {sup 11}C-choline PET/CT findings were validated by transrectal ultrasound-guided biopsy or at least 12 months of follow-up with contrast-enhanced CT, MR, bone scintigraphy or a repeated {sup 11}C-choline PET/CT scan. The relationships between the detection rate of {sup 11}C-choline PET/CT and the factors PSA level, PSA kinetics, Gleason score, age, time to relapse and SUVmax in patients with positive findings were analysed. {sup 11}C-Choline PET/CT detected the site of relapse in 123 of the 140 patients with a detection rate of 87.8 % (46 patients showed local relapse, 31 showed local and distant relapse, and 46 showed only distant relapse). In patients with relapse the mean serum PSA level was 9.08 ng/mL (median 5.1 ng/mL, range 2 - 60 ng/mL), the mean PSA doubling time was 5.6 months (median 3.5 months, range 0.4 - 48 months), and the mean PSA velocity was 15 ng/mL/year (median 8.8 ng/mL/year, range 0.4 - 87 ng/mL/year). Of the 123 patients with relapse, 77 (62.6 %) showed distant relapse with/without local relapse, and of these 77, 31 (40.2 %) showed oligometastatic disease (one or two distant lesions: lymph node lesions only in 16, bone lesions only in 14, and lymph node lesions and bone

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

    Energy Technology Data Exchange (ETDEWEB)

    Mendrik, Adrienne M; Van Ginneken, Bram; Viergever, Max A [Image Sciences Institute, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands); Vonken, Evert-jan; De Jong, Hugo W; Riordan, Alan; Van Seeters, Tom; Smit, Ewoud J; Prokop, Mathias, E-mail: a.m.mendrik@gmail.com [Radiology Department, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht (Netherlands)

    2011-07-07

    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 radiation that can be used per sequential scan is limited, which results in a high level of noise. To detect areas of abnormal perfusion, perfusion parameters are derived from the CTP data, such as the cerebral blood flow (CBF). Algorithms to determine perfusion parameters, especially singular value decomposition, are very sensitive to noise. Therefore, noise reduction is an important preprocessing step for CTP analysis. In this paper, we propose a time-intensity profile similarity (TIPS) bilateral filter to reduce noise in 4D CTP scans, while preserving the time-intensity profiles (fourth dimension) that are essential for determining the perfusion parameters. The proposed TIPS bilateral filter is compared to standard Gaussian filtering, and 4D and 3D (applied separately to each sequential scan) bilateral filtering on both phantom and patient data. Results on the phantom data show that the TIPS bilateral filter is best able to approach the ground truth (noise-free phantom), compared to the other filtering methods (lowest root mean square error). An observer study is performed using CBF maps derived from fifteen CTP scans of acute stroke patients filtered with standard Gaussian, 3D, 4D and TIPS bilateral filtering. These CBF maps were blindly presented to two observers that indicated which map they preferred for (1) gray/white matter differentiation, (2) detectability of infarcted area and (3) overall image quality. Based on these results, the TIPS bilateral filter ranked best and its CBF maps were scored to have the best overall image quality in 100% of the cases by both observers. Furthermore, quantitative CBF and cerebral blood volume values in both the phantom and the

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

    Science.gov (United States)

    Mendrik, Adriënne M.; Vonken, Evert-jan; van Ginneken, Bram; de Jong, Hugo W.; Riordan, Alan; van Seeters, Tom; Smit, Ewoud J.; Viergever, Max A.; Prokop, Mathias

    2011-07-01

    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 radiation that can be used per sequential scan is limited, which results in a high level of noise. To detect areas of abnormal perfusion, perfusion parameters are derived from the CTP data, such as the cerebral blood flow (CBF). Algorithms to determine perfusion parameters, especially singular value decomposition, are very sensitive to noise. Therefore, noise reduction is an important preprocessing step for CTP analysis. In this paper, we propose a time-intensity profile similarity (TIPS) bilateral filter to reduce noise in 4D CTP scans, while preserving the time-intensity profiles (fourth dimension) that are essential for determining the perfusion parameters. The proposed TIPS bilateral filter is compared to standard Gaussian filtering, and 4D and 3D (applied separately to each sequential scan) bilateral filtering on both phantom and patient data. Results on the phantom data show that the TIPS bilateral filter is best able to approach the ground truth (noise-free phantom), compared to the other filtering methods (lowest root mean square error). An observer study is performed using CBF maps derived from fifteen CTP scans of acute stroke patients filtered with standard Gaussian, 3D, 4D and TIPS bilateral filtering. These CBF maps were blindly presented to two observers that indicated which map they preferred for (1) gray/white matter differentiation, (2) detectability of infarcted area and (3) overall image quality. Based on these results, the TIPS bilateral filter ranked best and its CBF maps were scored to have the best overall image quality in 100% of the cases by both observers. Furthermore, quantitative CBF and cerebral blood volume values in both the phantom and the

  15. Dual-time point scanning of integrated FDG PET/CT for the evaluation of mediastinal and hilar lymph nodes in non-small cell lung cancer diagnosed as operable by contrast-enhanced CT

    Energy Technology Data Exchange (ETDEWEB)

    Kasai, Takami, E-mail: takaby@hotmail.co [Department of Radiology, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba-ken 260-8677 (Japan); Motoori, Ken, E-mail: motoorik@faculty.chiba-u.j [Department of Radiology, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba-ken 260-8677 (Japan); Horikoshi, Takuro, E-mail: taku_steelfish@yahoo.co.j [Department of Radiology, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba-ken 260-8677 (Japan); Uchiyama, Katsuhiro, E-mail: ka-uchiyama@nifty.co [Diagnostic PET Imaging Center, Department of Radiology, Sannoh Medical Center, 166-2 Sannohcho, Inage-ku, Chiba City, Chiba-ken 263-0002 (Japan); Yasufuku, Kazuhiro, E-mail: kyasufuku@faculty.chiba-u.j [Department of Thoracic Surgery, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba-ken 260-8670 (Japan); Takiguchi, Yuichi, E-mail: takiguchi@faculty.chiba-u.j [Department of Respirology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba-ken 260-8670 (Japan); Takahashi, Fumiaki, E-mail: takahashifu@pharm.kitasato-u.ac.j [Division of Biostatistics, Graduate School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Minato-ku, Tokyo 108-8641 (Japan); Kuniyasu, Yoshio, E-mail: kuniyasu@ace.ocn.ne.j [Diagnostic PET Imaging Center, Department of Radiology, Sannoh Medical Center, 166-2 Sannohcho, Inage-ku, Chiba City, Chiba-ken 263-0002 (Japan); Ito, Hisao, E-mail: hisao@faculty.chiba-u.j [Department of Radiology, Chiba University Hospital, 1-8-1 Inohana, Chuo-ku, Chiba City, Chiba-ken 260-8677 (Japan)

    2010-08-15

    Purpose: To evaluate whether dual-time point scanning with integrated fluorine-18 fluorodeoxyglucose ({sup 18}F-FDG) positron emission tomography and computed tomography (PET/CT) is useful for evaluation of mediastinal and hilar lymph nodes in non-small cell lung cancer diagnosed as operable by contrast-enhanced CT. Materials and methods: PET/CT data and pathological findings of 560 nodal stations in 129 patients with pathologically proven non-small cell lung cancer diagnosed as operable by contrast-enhanced CT were reviewed retrospectively. Standardized uptake values (SUVs) on early scans (SUVe) 1 h, and on delayed scans (SUVd) 2 h after FDG injection of each nodal station were measured. Retention index (RI) (%) was calculated by subtracting SUVe from SUVd and dividing by SUVe. Logistic regression analysis was performed with seven kinds of models, consisting of (1) SUVe, (2) SUVd, (3) RI, (4) SUVe and SUVd, (5) SUVe and RI, (6) SUVd and RI, and (7) SUVe, SUVd and RI. The seven derived models were compared by receiver-operating characteristic (ROC) analysis. k-Fold cross-validation was performed with k values of 5 and 10. p < 0.05 was considered statistically significant. Results: Model (1) including the term of SUVe showed the largest area under the ROC curve among the seven models. The cut-off probability of metastasis of 3.5% with SUVe of 2.5 revealed a sensitivity of 78% and a specificity of 81% on ROC analysis, and approximately 60% and 80% on k-fold cross-validation. Conclusion: Single scanning of PET/CT is sufficiently useful for evaluating mediastinal and hilar nodes for metastasis.

  16. Case of huge neurofibroma expanding extra- and intracranially through the enlarged jugular foramen. CT scan findings and surgical approach

    Energy Technology Data Exchange (ETDEWEB)

    Hanakita, Junya; Imataka, Kiyoharu; Handa, Hajime (Kyoto Univ. (Japan). Faculty of Medicine)

    1984-01-01

    The surgical approach to the jugular foramen has been considered to be very difficult and troublesome, because of the location in which important structures, such as the internal jugular vein, internal carotid artery and lower cranial nerves, converge in the narrow deep space. A case of huge neurofibroma, which extended from the tentorium cerebelli through the dilated jugular foramen to the level of the vertebral body of C/sub 3/ was presented. A 12-year-old girl was admitted with complaints of visual disturbance and palsy of the V-XII cranial nerves of the left side. Plain skull film showed prominent widening of the cranial sutures and enlargement of the sella turcica. Horizontal CT scan with contrast showed symmetrical ventricular dilatation and a heterogeneously enhanced mass, which was situated mainly in the left CP angle. Coronal CT scan with contrast revealed a huge mass and enlarged jugular foramen, through which the tumor extended to the level of the vertebral body of C/sub 3/. Occlusion of the sigmoid sinus and the internal jugular vein of the left side was noticed in the vertebral angiography. Two-stage approach, the first one for removal of the intracranial tumor and the second one for extracranial tumor, was performed for its huge tumor. Several authors have reported excellent surgical approaches for the tumors situated in the jugular foramen. By our approach, modifying Gardner's original one, a wide operative field was obtained to remove the tumor around the jugular foramen with success. Our approach for the jugular foramen was described with illustrations.

  17. 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....... 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...... and Bland-Altman analysis. Results: For HYPR-LR, a good correlation was found for relative segmental perfusion for both stress (y=1.007x+0.313, R2=0.98) and rest (y=1.007x+ 0.421, R2=0.96) scans with negative bias of -0.79±1.44 and -0.90±1.63, respectively. Correlations for SSS (R2=0.94), SRS (R2=0.92), SDS...

  18. 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...... sulphate contamination in a gradient with Cu content varies from 21 mg kg-1 to 3837 mg kg-1. Total 20 intact soil columns (diameter of 10 cm and height of 8 cm) were sampled at five locations along the Cu-gradient from a depth of 5 to 15 cm below surface level. The soil columns were scanned at a voxel...

  19. Feasibility of quantitative lung perfusion by 4D CT imaging by a new dynamic-scanning protocol in an animal model

    Science.gov (United States)

    Wang, Yang; Goldin, Jonathan G.; Abtin, Fereidoun G.; Brown, Matt; McNitt-Gray, Mike

    2008-03-01

    The purpose of this study is to test a new dynamic Perfusion-CT imaging protocol in an animal model and investigate the feasibility of quantifying perfusion of lung parenchyma to perform functional analysis from 4D CT image data. A novel perfusion-CT protocol was designed with 25 scanning time points: the first at baseline and 24 scans after a bolus injection of contrast material. Post-contrast CT scanning images were acquired with a high sampling rate before the first blood recirculation and then a relatively low sampling rate until 10 minutes after administrating contrast agent. Lower radiation techniques were used to keep the radiation dose to an acceptable level. 2 Yorkshire swine with pulmonary emboli underwent this perfusion- CT protocol at suspended end inspiration. The software tools were designed to measure the quantitative perfusion parameters (perfusion, permeability, relative blood volume, blood flow, wash-in & wash-out enhancement) of voxel or interesting area of lung. The perfusion values were calculated for further lung functional analysis and presented visually as contrast enhancement maps for the volume being examined. The results show increased CT temporal sampling rate provides the feasibility of quantifying lung function and evaluating the pulmonary emboli. Differences between areas with known perfusion defects and those without perfusion defects were observed. In conclusion, the techniques to calculate the lung perfusion on animal model have potential application in human lung functional analysis such as evaluation of functional effects of pulmonary embolism. With further study, these techniques might be applicable in human lung parenchyma characterization and possibly for lung nodule characterization.

  20. Effective doses associated with PET-CT scans two common in pediatric patients; Dosis efectivas asociadas a dos exploraciones PET-CT habituales en pacientes pediatricos

    Energy Technology Data Exchange (ETDEWEB)

    Camacho Lopez, C.; Garcia Martinez, M. t.; Marti Vidal, J. f.; Falgas Lacuela, M.; Vercher Conejero, J. L.

    2011-07-01

    The main objective of this paper is to outline the effective dose (E) that can be given in two studies conducted PET-CT common for children, in the absence of standard protocols both at standardizing the way image acquisition in this field, as standard levels to guide us when it comes to associate a certain effective dose to pediatric PET-CT scan. These doses will be compared to an adult patient receiving the same type of examination, and consider the percentage of the total dose due to TC.

  1. The value of chest CT scan and tumor markers detection in sputum for early diagnosis of peripheral lung cancer

    Institute of Scientific and Technical Information of China (English)

    WANG Xu; CAO Aihong; PENG Mengqing; HU Chunfeng; LIU Delin; GU Tao; LIU Hui

    2004-01-01

    Objective To investigate the diagnostic value of chest CT scan combined with telomerase activity and p16 gene methylation from exfoliated cells of sputum in 55 cases of solitary pulmonary nodules (SPN; ≤30 mm)suspected early peripheral lung cancer. Methods The sputum specimens from 34 cases of cancer nodules and 21 cases of benign lesion were detected for telomerase activity by TRAP-PCR-ELISA and p16 gene methylation by PCR-based methylation analysis. Results The qualitative diagnostic accuracy of CT scan was 61.8%(34/55) for SPN provided by pathology. Cytology analysis of sputum was positive in 13 cases (38.2%). Telomerase activity was positive in 29 cases: sensitivity was 79.4%, specificity was 90.5%, accuracy was 83.6%; p16 gene methylation was found in 11 cases: sensitivity was 32.4%, specificity was 100.0%, and accuracy was 58.2%. The sensitivity was increased to 86.1% by combination of telomerase activity and p16 gene methylation. Compared with nodules without malignant CT signs, expression of telomerase activity and p16 methylation of SPN with malignant CT signs (lobulation or spiculate protuberance or spicule sign) had a significant difference (P<0.01). Conclusion The results suggest that chest CT scan combined with telomerase activity and p16 gene methylation detection in sputum for patients with peripheral lung cancer may enhance the diagnostic value of radiology and conventional cytology.

  2. Pediatric minor head trauma: do cranial CT scans change the therapeutic approach?

    Science.gov (United States)

    Andrade, Felipe P; Montoro, Roberto; Oliveira, Renan; Loures, Gabriela; Flessak, Luana; Gross, Roberta; Donnabella, Camille; Puchnick, Andrea; Suzuki, Lisa; Regacini, Rodrigo

    2016-01-01

    OBJECTIVES: 1) To verify clinical signs correlated with appropriate cranial computed tomography scan indications and changes in the therapeutic approach in pediatric minor head trauma scenarios. 2) To estimate the radiation exposure of computed tomography scans with low dose protocols in the context of trauma and the additional associated risk. METHODS: Investigators reviewed the medical records of all children with minor head trauma, which was defined as a Glasgow coma scale ≥13 at the time of admission to the emergency room, who underwent computed tomography scans during the years of 2013 and 2014. A change in the therapeutic approach was defined as a neurosurgical intervention performed within 30 days, hospitalization, >12 hours of observation, or neuro-specialist evaluation. RESULTS: Of the 1006 children evaluated, 101 showed some abnormality on head computed tomography scans, including 49 who were hospitalized, 16 who remained under observation and 36 who were dismissed. No patient underwent neurosurgery. No statistically significant relationship was observed between patient age, time between trauma and admission, or signs/symptoms related to trauma and abnormal imaging results. A statistically significant relationship between abnormal image results and a fall higher than 1.0 meter was observed (p=0.044). The mean effective dose was 2.0 mSv (0.1 to 6.8 mSv), corresponding to an estimated additional cancer risk of 0.05%. CONCLUSION: A computed tomography scan after minor head injury in pediatric patients did not show clinically relevant abnormalities that could lead to neurosurgical indications. Patients who fell more than 1.0 m were more likely to have changes in imaging tests, although these changes did not require neurosurgical intervention; therefore, the use of computed tomography scans may be questioned in this group. The results support the trend of more careful indications for cranial computed tomography scans for children with minor head trauma.

  3. Clinical Usefulness of F-18 FDG PET/CT in papillary thyroid cancer with negative radioiodine scan and elevated thyroglobulin level or positive anti-thyroglobulin antibody

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Su Jung; Jung, Kyung Pyo; Lee, Sun Seong; Park, Yun Soo; Lee, Seok Mo [Dept. of Nuclear Medicine, Busan Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of); Bae, Sang Kyun [Dept. of Nuclear Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan (Korea, Republic of)

    2016-06-15

    Elevated thyroglobulin (Tg) levels, along with a negative radioiodine scan, present a clinical problem for the diagnosis of recurrence in papillary thyroid cancer (PTC) patients. The purpose of this study was to assess (1) the usefulness of 18F-fluorodeoxyglucose (F-18 FDG) positron emission tomography (PET)/computed tomography (CT) for PTC patients with negative diagnostic radioiodine scan and elevated serum Tg level or positive anti-thyroglobulin antibody (TgAb), and (2) the effect of endogenous thyroid stimulating hormone (TSH) stimulation (ETS) on detecting recurrence in these circumstances. Eighty-four patients with negative diagnostic radioiodine scan and elevated serum Tg or positive TgAb under ETS were included. Correlation with clinicopathological features and recurrence, detectability of FDG PET/CT and cut-off value of serum Tg for recurrence in PTC patients with these circumstance were assessed. In addition, detectability of F-18 FDG PET/CT under ETS and suppression were compared. In Cox regression analysis, only serum Tg level was significantly associated with recurrence (P<0.001, HR  = 1.13; 95 % CI, 1.061–1.208). The cut-off level of Tg was 21.5 ng/mL (AUC, 0.919; P < 0.001) for discriminating the recurrence in the patients with positive PET/CT finding. The sensitivity, specificity, PPV, NPV, and accuracy of F-18 FDG PET/CT for detecting recurrence were 64 %, 94 %, 86 %, 81 %, and 83 %. In the analysis of F-18 FDG PET/CT under ETS, the sensitivity, specificity, PPV, NPV and accuracy was 64 %, 94 %, 88 %, 81 % and 83 %. Those under TSH suppression were 67 %, 92 %, 80 %, 85 % and 83 %. F-18 FDG PET/CT, although less sensitive, showed high specificity, PPV, NPV, and accuracy and therefore can be useful for the patients with negative diagnostic radioiodine scan and elevated serum Tg or positive TgAb. In addition, FDG PET/CT under ETS does not seem to have an additive role in detecting recurrence in these patients.

  4. 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.

  5. 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.

  6. Delayed post-surgical sepsis from Teflon felt: The diagnostic value of CT scanning, and a reminder for theatre staff

    Directory of Open Access Journals (Sweden)

    D Emby

    2011-06-01

    Full Text Available We report on 2 patients with surgical site infections following the inadvertent use of Teflon felt for haemostasis in elective and emergency surgery. CT scanning was superior to plain radiography in demonstrating the foreign bodies to enable planning of further surgical treatment.

  7. 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;

    2015-01-01

    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...

  8. Place of the CT scan in the three concept view (TCV) of the low back syndrome. A preliminary survey

    Energy Technology Data Exchange (ETDEWEB)

    Geldermann, P.W. (Sophia Hospital, Zwolle (The Netherlands). Neurosurgical Dept.)

    1982-01-01

    From the historical lines along which our thinking about low back pain developed, three concepts can be deduced: radicular, stenotic and axial. The patient with a low back pain syndrome (LBS) should be seen with this three concept view (TCV) in mind. Modern insight into the degenerative process of the low back support this concept. The clinical syndromes illustrating these concepts, radicular syndromes, Neurogenic Peripheral Intermittent Claudication (NPIC), and axial low back pain, can intermingle. To determine the place of the CT scan in the process of diagnosis of the LBS, we carried out a total of 56 CT-examinations on about 200 low back patients with various indications. The results are discussed. In addition to radiological suppositions, NPIC plays an important part in deciding whether or not to perform a CT scan.

  9. Experiences of using a single post-contrast CT scan of the urinary tract after triphasic contrast injection

    Directory of Open Access Journals (Sweden)

    Phillip Carl Pretorius

    2011-12-01

    Full Text Available I was alerted to an article in Radiology Vol. 255 No. 2 (May 20101 by a colleague. The article, entitled ‘Kidney and urinary tract imaging: Triple-bolus multidetector CT urography as a one-stop shop – Protocol design, opacification, and image quality analysis’, clearly describes the technique, while the quotation below, from the article, summarises the findings: ‘We have shown that triple-bolus multidetector CT urography allowed visualization of renal parenchymal, excretory, and vascular contrast-enhancement phases in a single dose-efficient acquisition and provided sufficient opacification of the UUT, with simultaneous and adequate image quality of renal parenchyma and vascular anatomy.’ The main emphasis on this technique is to reduce the number of unnecessary CT scans when assessing the urinary tract. Our previous protocol for scanning the urinary tract for pathology included four phases: a pre-contrast, corticomedullary, nephrographic and delay excretory phase.

  10. 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

  11. Investigation of the vestibular aqueduct and the cochlear aqueduct by temporal bone CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Ryuichi; Kamei, Tamio; Ito, Fumihide (Gunma Univ., Maebashi (Japan). School of Medicine)

    1984-02-01

    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.

  12. A CAD of fully automated colonic polyp detection for contrasted and non-contrasted CT scans.

    Science.gov (United States)

    Tulum, Gökalp; Bolat, Bülent; Osman, Onur

    2017-04-01

    Computer-aided detection (CAD) systems are developed to help radiologists detect colonic polyps over CT scans. It is possible to reduce the detection time and increase the detection accuracy rates by using CAD systems. In this paper, we aimed to develop a fully integrated CAD system for automated detection of polyps that yields a high polyp detection rate with a reasonable number of false positives. The proposed CAD system is a multistage implementation whose main components are: automatic colon segmentation, candidate detection, feature extraction and classification. The first element of the algorithm includes a discrete segmentation for both air and fluid regions. Colon-air regions were determined based on adaptive thresholding, and the volume/length measure was used to detect air regions. To extract the colon-fluid regions, a rule-based connectivity test was used to detect the regions belong to the colon. Potential polyp candidates were detected based on the 3D Laplacian of Gaussian filter. The geometrical features were used to reduce false-positive detections. A 2D projection image was generated to extract discriminative features as the inputs of an artificial neural network classifier. Our CAD system performs at 100% sensitivity for polyps larger than 9 mm, 95.83% sensitivity for polyps 6-10 mm and 85.71% sensitivity for polyps smaller than 6 mm with 5.3 false positives per dataset. Also, clinically relevant polyps ([Formula: see text]6 mm) were identified with 96.67% sensitivity at 1.12 FP/dataset. To the best of our knowledge, the novel polyp candidate detection system which determines polyp candidates with LoG filters is one of the main contributions. We also propose a new 2D projection image calculation scheme to determine the distinctive features. We believe that our CAD system is highly effective for assisting radiologist interpreting CT.

  13. Automatic detection of patients with invasive fungal disease from free-text computed tomography (CT) scans.

    Science.gov (United States)

    Martinez, David; Ananda-Rajah, Michelle R; Suominen, Hanna; Slavin, Monica A; Thursky, Karin A; Cavedon, Lawrence

    2015-02-01

    Invasive fungal diseases (IFDs) are associated with considerable health and economic costs. Surveillance of the more diagnostically challenging invasive fungal diseases, specifically of the sino-pulmonary system, is not feasible for many hospitals because case finding is a costly and labour intensive exercise. We developed text classifiers for detecting such IFDs from free-text radiology (CT) reports, using machine-learning techniques. We obtained free-text reports of CT scans performed over a specific hospitalisation period (2003-2011), for 264 IFD and 289 control patients from three tertiary hospitals. We analysed IFD evidence at patient, report, and sentence levels. Three infectious disease experts annotated the reports of 73 IFD-positive patients for language suggestive of IFD at sentence level, and graded the sentences as to whether they suggested or excluded the presence of IFD. Reliable agreement between annotators was obtained and this was used as training data for our classifiers. We tested a variety of Machine Learning (ML), rule based, and hybrid systems, with feature types including bags of words, bags of phrases, and bags of concepts, as well as report-level structured features. Evaluation was carried out over a robust framework with separate Development and Held-Out datasets. The best systems (using Support Vector Machines) achieved very high recall at report- and patient-levels over unseen data: 95% and 100% respectively. Precision at report-level over held-out data was 71%; however, most of the associated false-positive reports (53%) belonged to patients who had a previous positive report appropriately flagged by the classifier, reducing negative impact in practice. Our machine learning application holds the potential for developing systematic IFD surveillance systems for hospital populations. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. What Can Computed Tomography Scans of the Thorax Show after Breast Surgery?

    Directory of Open Access Journals (Sweden)

    Afsaneh Alikhassi

    2016-06-01

    Full Text Available Background: Postoperative breast abnormalities after breast conserving surgery or modified radical mastectomy are frequently overlooked and inaccurately assessed or reported using multidetector computed tomography (MDCT. These inaccurate results may have legal ramifications for the clinicians, cause patients avoidable anxiety, and lead to additional unnecessary diagnostic follow-up testing and costs.Methods: The patients with a history of breast cancer who had undergone breast-conserving surgery or modified radical mastectomy up to 6 months prior to undergoing a thoracic MDCT scan consented and enrolled in this study. These patients underwent a thoracic MDCT scan either because of respiratory or cardiac clinical symptoms or as part of breast cancer staging.Results: Forty women were included in this study. Different postoperative breast changes observed on thoracic MDCT scans including fibrous scar tissue, fat necrosis, seroma, abscess, hematoma, and recurrent and residual tumor were described.Conclusions: MDCT scans offer sufficient evidence in many postoperative cases to allow a confident diagnosis. General radiologists who review thoracic MDCT scans should know how to characterize breast lesions incidentally found on MDCT scans after breast surgeries. This information would enhance the value of the radiologist’s report for appropriate case management.

  15. 4D CT amplitude binning for the generation of a time-averaged 3D mid-position CT scan.

    Science.gov (United States)

    Kruis, Matthijs F; van de Kamer, Jeroen B; Belderbos, José S A; Sonke, Jan-Jakob; van Herk, Marcel

    2014-09-21

    The purpose of this study was to develop a method to use amplitude binned 4D-CT (A-4D-CT) data for the construction of mid-position CT data and to compare the results with data created from phase-binned 4D-CT (P-4D-CT) data. For the latter purpose we have developed two measures which describe the regularity of the 4D data and we have tried to correlate these measures with the regularity of the external respiration signal. 4D-CT data was acquired for 27 patients on a combined PET-CT scanner. The 4D data were reconstructed twice, using phase and amplitude binning. The 4D frames of each dataset were registered using a quadrature-based optical flow method. After registration the deformation vector field was repositioned to the mid-position. Since amplitude-binned 4D data does not provide temporal information, we corrected the mid-position for the occupancy of the bins. We quantified the differences between the two mid-position datasets in terms of tumour offset and amplitude differences. Furthermore, we measured the standard deviation of the image intensity over the respiration after registration (σregistration) and the regularity of the deformation vector field (Delta J) to quantify the quality of the 4D-CT data. These measures were correlated to the regularity of the external respiration signal (σsignal).The two irregularity measures, Delta J and σregistration, were dependent on each other (p<0.0001, R2=0.80 for P-4D-CT, R2=0.74 for A-4D-CT). For all datasets amplitude binning resulted in lower Delta J and σregistration and large decreases led to visible quality improvements in the mid-position data. The quantity of artefact decrease was correlated to the irregularity of the external respiratory signal.The average tumour offset between the phase and amplitude binned mid-position without occupancy correction was 0.42 mm in the caudal direction (10.6% of the amplitude). After correction this was reduced to 0.16 mm in caudal direction (4.1% of the amplitude

  16. Effect of deformable registration on the dose calculated in radiation therapy planning CT scans of lung cancer patients

    Energy Technology Data Exchange (ETDEWEB)

    Cunliffe, Alexandra R.; Armato, Samuel G.; White, Bradley; Justusson, Julia [Department of Radiology, The University of Chicago, 5841 South Maryland Avenue, Chicago, Illinois 60637 (United States); Contee, Clay; Malik, Renuka; Al-Hallaq, Hania A., E-mail: hal-hallaq@radonc.uchicago.edu [Department of Radiation and Cellular Oncology, The University of Chicago, 5841 South Maryland Avenue, Chicago, Illinois 60637 (United States)

    2015-01-15

    Purpose: To characterize the effects of deformable image registration of serial computed tomography (CT) scans on the radiation dose calculated from a treatment planning scan. Methods: Eighteen patients who received curative doses (≥60 Gy, 2 Gy/fraction) of photon radiation therapy for lung cancer treatment were retrospectively identified. For each patient, a diagnostic-quality pretherapy (4–75 days) CT scan and a treatment planning scan with an associated dose map were collected. To establish correspondence between scan pairs, a researcher manually identified anatomically corresponding landmark point pairs between the two scans. Pretherapy scans then were coregistered with planning scans (and associated dose maps) using the demons deformable registration algorithm and two variants of the Fraunhofer MEVIS algorithm (“Fast” and “EMPIRE10”). Landmark points in each pretherapy scan were automatically mapped to the planning scan using the displacement vector field output from each of the three algorithms. The Euclidean distance between manually and automatically mapped landmark points (d{sub E}) and the absolute difference in planned dose (|ΔD|) were calculated. Using regression modeling, |ΔD| was modeled as a function of d{sub E}, dose (D), dose standard deviation (SD{sub dose}) in an eight-pixel neighborhood, and the registration algorithm used. Results: Over 1400 landmark point pairs were identified, with 58–93 (median: 84) points identified per patient. Average |ΔD| across patients was 3.5 Gy (range: 0.9–10.6 Gy). Registration accuracy was highest using the Fraunhofer MEVIS EMPIRE10 algorithm, with an average d{sub E} across patients of 5.2 mm (compared with >7 mm for the other two algorithms). Consequently, average |ΔD| was also lowest using the Fraunhofer MEVIS EMPIRE10 algorithm. |ΔD| increased significantly as a function of d{sub E} (0.42 Gy/mm), D (0.05 Gy/Gy), SD{sub dose} (1.4 Gy/Gy), and the algorithm used (≤1 Gy). Conclusions: An

  17. A new method of CT scanning for the diagnosis of mandibular fractures; A preliminary report: diagnosis of condyle fractures

    Energy Technology Data Exchange (ETDEWEB)

    Tsukagoshi, Taku; Satoh, Kaneshige; Onizuka, Takuya (Showa Univ., Tokyo (Japan). School of Medicine)

    1990-08-01

    The condylar neck of the mandible is one of the most common fracture sites in the facial skeleton. Such a fracture is routinely diagnosed by A-P, lateral oblique, and Towne projection roentgenography or orthopantomography. Despite the combination of these films, fracture of the neck of the mandible is still difficult to diagnose definitely. Therefore, a new CT scanning method was developed for diagnosing fractures of the neck of the condylar mandible. The CT axis is projected along the length of the mandible, extending from the condyle to the symphysis. This projection visualizes both the condyle and the mandibular symphysis in the same plane. The patient is placed in a supine position with the head fully extended. The base line, a line extending from the midpoint of the glenoid fossa to the menton, is determined with a lateral facial cephalogram. CT scanning with a 5 mm window is performed in parallel with and 2 cm anterior to and 2 cm posterior to the base line. When CT scanning was performed in a healthy volunteer, the condition of the condyle and the condylar neck of the mandible was clearly shown, and the view extended from the condyle to the symphysis. For automobile accident patients in whom fracture of the neck of the mandible was associated with fracture of the symphysis, two fractures were found in the same plane. A newly developed CT scanning technique is useful in the diagnosis of fractures of the condylar neck of the mandible and in the identification of fractures at other mandibular sites. It also allows scanning of patients in a supine position, which may aid in managing patients with multiple traumas. (N.K.).

  18. Comparison between FDG Uptake and Pathologic or Immunohistochemical Parametersin Pre-operative PET/CT Scan of Patient with Primary Colorectal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Na, Sae Jung; Chung, Yong An; Maeng, Lee So; Kim, Ki Jun; Sohn, Kyung Myung; Kim, Sung Hoon; Sohn, Hyung Sun; Chung, Soo Kyo [College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2009-12-15

    To evaluate the relationship between F-18 FDG uptake of tumor in PET/CT scan and pathological or immunohistochemial parameters of colorectal cancer. 147 colorectal cancer patients who underwent both pre-operative F-18 FDG PET/CT scan and surgery were included. In cases with perceptible FDG uptake in primary tumor, the maximum standardized uptake value (SUVmax) was calculated. The pathologic results such as site, size, depth of invasion (T stage), growth pattern, differentiation of primary tumor, lymph node metastasis and Dukes-Astler and Coller stage and immunohistochemical markers such as expression of EGFR, MLH1, MSH2 and Ki-67 index were reviewed. 146 out of 147 PET/CT scans with colorectal cancer showed perceptible focal FDG uptake. SUVmax showed mild positive linear correlation with size of primary tumor (r=0.277, p=0.001) and Ki-67 index (r=0.226, p=0.019). No significant difference in F-18 FDG uptake was found according to site, depth of invasion (T stage), growth pattern, differentiation of primary tumor, presence of lymph node metastasis, Dukes-Astler and Coller stage and expression of EGFR. The degree of F-18 FDG uptake in colorectal cancer was associated with the size and the degree of Ki-67 index of primary tumor. It could be thought that FDG uptake of primary tumor has a correlation with macroscopic and microscopic tumor growth.

  19. Obtaining quantitative global tumoral state indicators based on whole-body PET/CT scans: a breast cancer case study.

    Science.gov (United States)

    Sampedro, Frederic; Domenech, Anna; Escalera, Sergio

    2014-04-01

    In this work we address the need for the computation of quantitative global tumoral state indicators from oncological whole-body PET/computed tomography scans. The combination of such indicators with other oncological information such as tumor markers or biopsy results would prove useful in oncological decision-making scenarios. From an ordering of 100 breast cancer patients on the basis of oncological state through visual analysis by a consensus of nuclear medicine specialists, a set of numerical indicators computed from image analysis of the PET/computed tomography scan is presented, which attempts to summarize a patient's oncological state in a quantitative manner taking into consideration the total tumor volume, aggressiveness, and spread. Results obtained by comparative analysis of the proposed indicators with respect to the experts' evaluation show up to 87% Pearson's correlation coefficient when providing expert-guided PET metabolic tumor volume segmentation and 64% correlation when using completely automatic image analysis techniques. Global quantitative tumor information obtained by whole-body PET/CT image analysis can prove useful in clinical nuclear medicine settings and oncological decision-making scenarios. The completely automatic computation of such indicators would improve its impact as time efficiency and specialist independence would be achieved.

  20. Virtual animation of victim-specific 3D models obtained from CT scans for forensic reconstructions: Living and dead subjects.

    Science.gov (United States)

    Villa, C; Olsen, K B; Hansen, S H

    2017-09-01

    Post-mortem CT scanning (PMCT) has been introduced at several forensic medical institutions many years ago and has proved to be a useful tool. 3D models of bones, skin, internal organs and bullet paths can rapidly be generated using post-processing software. These 3D models reflect the individual physiognomics and can be used to create whole-body 3D virtual animations. In such way, virtual reconstructions of the probable ante-mortem postures of victims can be constructed and contribute to understand the sequence of events. This procedure is demonstrated in two victims of gunshot injuries. Case #1 was a man showing three perforating gunshot wounds, who died due to the injuries of the incident. Whole-body PMCT was performed and 3D reconstructions of bones, relevant internal organs and bullet paths were generated. Using 3ds Max software and a human anatomy 3D model, a virtual animated body was built and probable ante-mortem postures visualized. Case #2 was a man presenting three perforating gunshot wounds, who survived the incident: one in the left arm and two in the thorax. Only CT scans of the thorax, abdomen and the injured arm were provided by the hospital. Therefore, a whole-body 3D model reflecting the anatomical proportions of the patient was made combining the actual bones of the victim with those obtained from the human anatomy 3D model. The resulted 3D model was used for the animation process. Several probable postures were also visualized in this case. It has be shown that in Case #1 the lesions and the bullet path were not consistent with an upright standing position; instead, the victim was slightly bent forward, i.e. he was sitting or running when he was shot. In Case #2, one of the bullets could have passed through the arm and continued into the thorax. In conclusion, specialized 3D modelling and animation techniques allow for the reconstruction of ante-mortem postures based on both PMCT and clinical CT. Copyright © 2017 Elsevier B.V. All rights

  1. Percutaneous Bone Biopsies: Comparison between Flat-Panel Cone-Beam CT and CT-Scan Guidance

    Energy Technology Data Exchange (ETDEWEB)

    Tselikas, Lambros, E-mail: lambros.tselikas@gmail.com; Joskin, Julien, E-mail: j.joskin@gmail.com [Gustave Roussy, Interventional Radiology Department (France); Roquet, Florian, E-mail: florianroquet@hotmail.com [Gustave Roussy, Biostatistics Department (France); Farouil, Geoffroy, E-mail: g.farouil@gmail.com [Gustave Roussy, Interventional Radiology Department (France); Dreuil, Serge, E-mail: serge.dreuil@gustaveroussy.fr [Gustave Roussy, Medical Physics Department (France); Hakimé, Antoine, E-mail: thakime@yahoo.com; Teriitehau, Christophe, E-mail: cteriitehau@me.com [Gustave Roussy, Interventional Radiology Department (France); Auperin, Anne, E-mail: anne.auperin@gustaveroussy.fr [Gustave Roussy, Biostatistics Department (France); Baere, Thierry de, E-mail: thierry.debaere@gustaveroussy.fr; Deschamps, Frederic, E-mail: frederic.deschamps@gustaveroussy.fr [Gustave Roussy, Interventional Radiology Department (France)

    2015-02-15

    PurposeThis study was designed to compare the accuracy of targeting and the radiation dose of bone biopsies performed either under fluoroscopic guidance using a cone-beam CT with real-time 3D image fusion software (FP-CBCT-guidance) or under conventional computed tomography guidance (CT-guidance).MethodsSixty-eight consecutive patients with a bone lesion were prospectively included. The bone biopsies were scheduled under FP-CBCT-guidance or under CT-guidance according to operating room availability. Thirty-four patients underwent a bone biopsy under FP-CBCT and 34 under CT-guidance. We prospectively compared the two guidance modalities for their technical success, accuracy, puncture time, and pathological success rate. Patient and physician radiation doses also were compared.ResultsAll biopsies were technically successful, with both guidance modalities. Accuracy was significantly better using FP-CBCT-guidance (3 and 5 mm respectively: p = 0.003). There was no significant difference in puncture time (32 and 31 min respectively, p = 0.51) nor in pathological results (88 and 88 % of pathological success respectively, p = 1). Patient radiation doses were significantly lower with FP-CBCT (45 vs. 136 mSv, p < 0.0001). The percentage of operators who received a dose higher than 0.001 mSv (dosimeter detection dose threshold) was lower with FP-CBCT than CT-guidance (27 vs. 59 %, p = 0.01).ConclusionsFP-CBCT-guidance for bone biopsy is accurate and reduces patient and operator radiation doses compared with CT-guidance.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    information. The lung was segmented automatically by in-house developed computer software, and the percentage of pixels below -950 HU was used as a surrogate marker for emphysema. The observer variability, as well as the correlation with the lung density measurements, was analysed using Spearman’s rank......Introduction – Emphysema is defined by pathology, but is most precisely evaluated in vivo by computed tomography (CT). Aims – were to determine the reproducibility of visual evaluation of emphysema, i.e. the observer variability, and furthermore to compare the visual evaluations to automatic CT...

  3. Effectiveness of second-opinion radiology consultations to reassess the cervical spine CT scans: a study on trauma patients referred to a tertiary-care hospital

    Science.gov (United States)

    Khalilzadeh, Omid; Rahimian, Maryam; Batchu, Vinay; Vadvala, Harshna V.; Novelline, Robert A.; Choy, Garry

    2015-01-01

    PURPOSE A second opinion is a valuable resource in confirming proper medical diagnosis and treatment. This study evaluates the effectiveness of second-opinion radiology consultations to reassess the cervical spine computed tomography (CT) scans of the trauma patients referred to our hospital. METHODS Cervical spine CT scans of 301 consecutive adult trauma patients, who were referred to our hospital from outside institutions, were analyzed. The emergency radiologists at our institution completed the over-read reports on the CT images obtained at the outside facilities. A single radiologist compared the outside- and over-read reports and determined the discrepancy of the radiologic reports. RESULTS Based on the outside reports, 31% of the CT scans had cervical traumatic injury. In 92% of patients, the first-read and the over-read reports had consistent radiologic findings. About 90% of the positive, and 93% of the negative radiologic findings, were reported consistently in the over-read reports. Our analysis showed that the over-read reporting resulted in reassurance of negative findings in 63%; confirmation of positive findings in 29%; clearing a false diagnosis in 3%; and detection of a missed diagnosis in 5%. A rescan was done in 80% of patients with inconsistent and 20% of patients with consistent findings (P < 0.05). The most common missed radiologic findings in the first-reports were transverse and spinous process fractures and the most common misdiagnoses were dens fractures. CONCLUSION For a service offering second-opinion consultations on cervical spine trauma, review of outside CT studies improves diagnosis and benefits patient care. PMID:26200483

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

    African Journals Online (AJOL)

    disability and makes considerable demands on health services. In developing ... and gender distribution, and CT findings related to acute head ... Conclusion: The high prevalence of head trauma related CT findings justify the use of CT in acute head trauma in. Eritrea. .... education and to earn the livelihood are more prone.

  5. Effect of CT scanning parameters on CT number%CT扫描参数对人体组织CT值影响的研究

    Institute of Scientific and Technical Information of China (English)

    彭文献; 彭天舟; 叶小琴; 付益谋; 潘慧平; 高源统; 金光波

    2010-01-01

    目的 探索不同CT扫描参数对人体同一种组织CT值的影响.方法 通过在同一台CT机上,分别改变其中1个扫描参数,如X线管电压、毫安秒和重建函数等,而保持其他扫描参数不变,多次扫描标准体模,测量和分析体模中不同物质的CT值.结果 X线管电压的改变对物质的CT值影响具有显著意义.聚乙烯、聚碳酸酯、有机玻璃的CT值与管电压成正相关;聚四氟乙烯的CT值与管电压成负相关.毫安秒和重建函数对CT值的影响差异无统计学意义.结论 同一个人体组织在不同的X线管电压条件下CT值是变化的.因此,在临床影像诊断和放疗中应该考虑图像扫描参数的设置对诊断和治疗结果的影响.%Objective To study the effects on tissue CT number caused by scan protocols.Methods The phantom was repeatedly scanned in different protocols by changing only one of parameters,such as X-ray tube voltage,mAs and recon kernel,while other parameters were ketp unchanged.The CT number of different materials in phantom were measured and analyzed.Results The CT numbers of tissues changed remarkably with the tube voltage and had different relativity for different tissues.The CT numbers had positive correlation with kV for such maierials as polyethyle,lexan,perspex,but for teflon the correlation was negative.The mAs and recon kernel had no effects on CT number.Conclusions The CT number of tissue changes with scanning X-ray tube voltage,so the setting of scan parameters should be taken into account in image diagnosis and radiotherapy.

  6. 螺旋CT对腹壁膨出的临床诊断价值%Clinical Application of Abdominal Wall Bulge with CT Scan

    Institute of Scientific and Technical Information of China (English)

    刘飞德; 邢新博; 李基业; 王世斌; 朱瑛梅; 姚胜

    2012-01-01

    目的 探讨螺旋CT对腹壁膨出的临床诊断价值.方法 收集本科就诊并行螺旋CT检查的腹壁膨出32例,观察腹壁膨出的部位及大小,行手术治疗者术后行螺旋CT复查手术效果.结果 32例腹壁膨出患者中,14例接受外科手术治疗,18例未行手术治疗.腹壁膨出在螺旋CT中表现为膨出区域的腹壁三层肌肉菲薄或消失,无明显疝囊或腹腔内容物疝出.术后螺旋CT复查可见膨出区域的侧腹壁三层肌肉及肌肉间隙出现,部分可见补片影.结论 螺旋CT对腹壁膨出的诊断和鉴别诊断具有确定性作用,同时可以为综合评估患者病情、选择手术方法及判断术后效果提供重要依据.%Objective To evaluate the clinical application of CT examination in abdominal wall bulge. Methods Retrospective study were carried out to 32 cases of abdominal wall bulge of which patients were accepted CT examination. The site and size of the bulge were evaluated, and postoperative CT examination was performed to evaluate the effect of the operation. Results Out of the 32 cases, 14 accepted surgical repair using synthetic mesh while the rest didn' t. CT scan demonstrated no facial defect or herniation of any intra-abdominal content in the bulge area, but the lateral abdominal wall musculature (external oblique, internal oblique, and transversus abdominal muscles) and/or rectus muscle on the bulge side appeared attenuated compared with the corresponding structures on the opposite side. The following CT scan check-up showed that the three layers of abdominal muscles on the bulge side appeared to be thicker compared with preoperative structures and the spaces between the three muscular layers emerged. And the mesh could be seen in some cases in CT scan. Conclusion CT scan is perfect in the diagnosis of the abdominal wall bulge and plays an important role in the evaluation of the patient situation, surgical technique and effectiveness of surgical repair.

  7. The first ant-termite syninclusion in amber with CT-scan analysis of taphonomy.

    Directory of Open Access Journals (Sweden)

    David Coty

    Full Text Available We describe here a co-occurrence (i.e. a syninclusion of ants and termites in a piece of Mexican amber (Totolapa deposit, Chiapas, whose importance is two-fold. First, this finding suggests at least a middle Miocene antiquity for the modern, though poorly documented, relationship between Azteca ants and Nasutitermes termites. Second, the presence of a Neivamyrmex army ant documents an in situ raiding behaviour of the same age and within the same community, confirmed by the fact that the army ant is holding one of the termite worker between its mandibles and by the presence of a termite with bitten abdomen. In addition, we present how CT-scan imaging can be an efficient tool to describe the topology of resin flows within amber pieces, and to point out the different states of preservation of the embedded insects. This can help achieving a better understanding of taphonomical processes, and tests ethological and ecological hypotheses in such complex syninclusions.

  8. Modeling the bifurcating flow in a CT-scanned human lung airway.

    Science.gov (United States)

    Luo, H Y; Liu, Y

    2008-08-28

    The inspiratory flow characteristics in a CT-scanned human lung model were numerically investigated using low Reynolds number (LRN) kappa-omega turbulent model. The five-generation airway is extracted from the trachea to segmental bronchi of a 60-year-old Chinese male patient. Computations were carried out in the Reynolds number range of 900-2100, corresponding to mouth-air breathing rates of 190-440 ml/s. Flow patterns on the Re=2100 and flow rate distribution were presented. In this model, the flow pattern is very complex. To count the effect of laryngeal jet on trachea inlet, the trachea was extended and modified to simulate the larynx, consequently the inlet velocity profile is biased towards the rear wall. In the inferior lobar bronchi, there are two stems in which the axial velocity is stronger but secondary velocity is weaker. Secondary flow in the lateral bronchi is stronger than the medial ones. With increasing Re, the air flow increases in the middle, inferior lobes and left main bronchus, i.e., flow biases to left and downward.

  9. Upper airway finding on CT scan with and without nasal CPAP in obstructive sleep apnea patients

    Energy Technology Data Exchange (ETDEWEB)

    Akashiba, Tsuneto; Sasaki, Iwao; Kurashina, Keiji; Yoshizawa, Takayuki; Otsuka, Kenzo; Horie, Takashi (Nihon Univ., Tokyo (Japan). School of Medicine)

    1991-04-01

    The area of upper airway (from the nasopharynx to the hypopharynx) was measured by means of computed tomography (CT) scan in 15 confirmed cases of obstructive sleep apnea (OSA) and in 4 normal controls while they were awake. The minimum cross-sectional area (MA) of the upper airway was 14.7+-20.0 mm{sup 2} in OSA patients and 80.0+-33.1 mm{sup 2} in normal controls and the difference was statistically significant (p<0.01). In OSA patients, MA did not correlate with age, body weight, apnea index, desaturation index, mean nadir-SO{sub 2} and lowest SO{sub 2}. MA was also measured with OSA patients while nasal continuous positive airway pressure (NCPAP) of 10 cmH{sub 2}O was applied and it was found that MA was significantly widened when NCPAP therapy was performed. We conclude that upper airway narrowing is consistent finding in OSA patients but the degree of narrowing does not correlate with parameters of apnea and gas exchange during sleep, and NCPAP is effective to widen the area of upper airway in OSA patients. (author).

  10. Preliminary experiments on pharmacokinetic diffuse fluorescence tomography of CT-scanning mode

    Science.gov (United States)

    Zhang, Yanqi; Wang, Xin; Yin, Guoyan; Li, Jiao; Zhou, Zhongxing; Zhao, Huijuan; Gao, Feng; Zhang, Limin

    2016-10-01

    In vivo tomographic imaging of the fluorescence pharmacokinetic parameters in tissues can provide additional specific and quantitative physiological and pathological information to that of fluorescence concentration. This modality normally requires a highly-sensitive diffuse fluorescence tomography (DFT) working in dynamic way to finally extract the pharmacokinetic parameters from the measured pharmacokinetics-associated temporally-varying boundary intensity. This paper is devoted to preliminary experimental validation of our proposed direct reconstruction scheme of instantaneous sampling based pharmacokinetic-DFT: A highly-sensitive DFT system of CT-scanning mode working with parallel four photomultiplier-tube photon-counting channels is developed to generate an instantaneous sampling dataset; A direct reconstruction scheme then extracts images of the pharmacokinetic parameters using the adaptive-EKF strategy. We design a dynamic phantom that can simulate the agent metabolism in living tissue. The results of the dynamic phantom experiments verify the validity of the experiment system and reconstruction algorithms, and demonstrate that system provides good resolution, high sensitivity and quantitativeness at different pump speed.

  11. Sex determination from scapular length measurements by CT scans images in a Caucasian population.

    Science.gov (United States)

    Giurazza, F; Schena, E; Del Vescovo, R; Cazzato, R L; Mortato, L; Saccomandi, P; Paternostro, F; Onofri, L; Zobel, B Beomonte

    2013-01-01

    Together with race, stature and age, sex is a main component of the biological identity. Thanks to its proportional correlation with parts of the human body, sex can be evaluated form the skeleton. The most accurate approach to determine sex by bone size is based on os coxae or skull. After natural disaster their presence can never be guaranteed, therefore the development of methods of sex determination using other skeletal elements can result crucial. Herein, sexual dimorphism in the human scapula is used to develop a two-variable discriminant function for sex estimation. We have enrolled 100 males and 100 females who underwent thoracic CT scan evaluation and we have estimated two scapular diameters. The estimation has been carried out by analyzing images of the scapulae of each patient after three dimensional post-processing reconstructions. The two-variable function allows to obtain an overall accuracy of 88% on the calibration sample. Furthermore, we have employed the mentioned function on a collection of 10 individual test sample from the collection of the "Museo di Anatomia Umana di Firenze" of the Università degli Studi di Firenze; sex has been correctly predicted on 9 skeletons.

  12. A three-dimensional reconstruction of the temporal bone by the helical scanning CT and its clinical application

    Energy Technology Data Exchange (ETDEWEB)

    Yonekawa, Hiroyuki; Ohashi, Masami; Miyashita, Souji; Gotoh, Mizuho; Nemoto, Satohiko; Kikuchi, Hideki (Azabu Triology Hospital, Sapporo (Japan)); Sakai, Noboru; Inuyama, Yukio

    1993-09-01

    The current availability of 3 dimensional (3-D) imaging from Computed Tomography (CT) has yielded new anatomical information and pre- and postoperative evaluations. However, little discussion as to the 3-D structural image of the temporal bone has been reported because conventional CT does provide sufficient data to produce such images. The helical scanning CT gathers continuous and multiple slice image data since it consists of an X-ray tube that continuously rotates around the patient while the patient moves continuously into the CT scanner. Thus, application of the helical scanning CT has made it possible to reconstruct 3-D images of the minute and complicated structure of the temporal bone. We evaluated 3-D images from 9 typical cases, examined from February to October 1992. As a result, we found that the 3-D images reconstructed with this system are useful for evaluation of the postoperative state of tympanoplasty, the diagnosis of anomalies of the bony labyrinth, and examining the extent of bone destruction induced by trauma, cholesteatoma, etc. (author).

  13. Indication for shunt operation of normal pressure hydrocephalus. Combined assessment of infusion test and dynamic CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Jinnai, Takahiro; Nagao, Seigo [Kagawa Medical Univ., Miki (Japan); Kuyama, Hideyuki

    2000-03-01

    Normal pressure hydrocephalus (NPH) is one of the diseases that causes a neuro-surgically treatable form of dementia. Although patients with NPH can be treated with shunt operation, reliable indications for the surgery are not yet established. In this study, 20 NPH patients diagnosed by clinical symptoms were subjected to combined assessment by infusion test and dynamic CT scan, a useful diagnostic tool to select a shunt responsive cases. Patients were evaluated by measuring sequential changes in the density of the periventricular lucency (PVL) using dynamic CT scan and continuous lumbar subdural pressure monitoring during an infusion manometric test at a rate of 0.8 ml/min for 30 min. The average lumbar subdural pressure during infusion manometric test in the shunt responsive group was 18.4{+-}5.8 mmHg, which was significantly higher than that in the shunt non-responsive group which was 10.0{+-}4.0 mmHg (p<0.01). The relative changes in PVL density in the dynamic CT was also significantly higher in the shunt responsive group (0.99{+-}0.61 HU) compared to the shunt non-responsive group (0.15{+-}0.32) (p<0.01). Dynamic CT scan with infusion manometric test is useful in the selection of patients with NPH who are likely to respond to shunt surgery. (author)

  14. Automatic identification of IASLC-defined mediastinal lymph node stations on CT scans using multi-atlas organ segmentation

    Science.gov (United States)

    Hoffman, Joanne; Liu, Jiamin; Turkbey, Evrim; Kim, Lauren; Summers, Ronald M.

    2015-03-01

    Station-labeling of mediastinal lymph nodes is typically performed to identify the location of enlarged nodes for cancer staging. Stations are usually assigned in clinical radiology practice manually by qualitative visual assessment on CT scans, which is time consuming and highly variable. In this paper, we developed a method that automatically recognizes the lymph node stations in thoracic CT scans based on the anatomical organs in the mediastinum. First, the trachea, lungs, and spines are automatically segmented to locate the mediastinum region. Then, eight more anatomical organs are simultaneously identified by multi-atlas segmentation. Finally, with the segmentation of those anatomical organs, we convert the text definitions of the International Association for the Study of Lung Cancer (IASLC) lymph node map into patient-specific color-coded CT image maps. Thus, a lymph node station is automatically assigned to each lymph node. We applied this system to CT scans of 86 patients with 336 mediastinal lymph nodes measuring equal or greater than 10 mm. 84.8% of mediastinal lymph nodes were correctly mapped to their stations.

  15. Comparison of Two Deformable Registration Algorithms in the Presence of Radiologic Change Between Serial Lung CT Scans.

    Science.gov (United States)

    Cunliffe, Alexandra R; White, Bradley; Justusson, Julia; Straus, Christopher; Malik, Renuka; Al-Hallaq, Hania A; Armato, Samuel G

    2015-12-01

    We evaluated the image registration accuracy achieved using two deformable registration algorithms when radiation-induced normal tissue changes were present between serial computed tomography (CT) scans. Two thoracic CT scans were collected for each of 24 patients who underwent radiation therapy (RT) treatment for lung cancer, eight of whom experienced radiologically evident normal tissue damage between pre- and post-RT scan acquisition. For each patient, 100 landmark point pairs were manually placed in anatomically corresponding locations between each pre- and post-RT scan. Each post-RT scan was then registered to the pre-RT scan using (1) the Plastimatch demons algorithm and (2) the Fraunhofer MEVIS algorithm. The registration accuracy for each scan pair was evaluated by comparing the distance between landmark points that were manually placed in the post-RT scans and points that were automatically mapped from pre- to post-RT scans using the displacement vector fields output by the two registration algorithms. For both algorithms, the registration accuracy was significantly decreased when normal tissue damage was present in the post-RT scan. Using the Plastimatch algorithm, registration accuracy was 2.4 mm, on average, in the absence of radiation-induced damage and 4.6 mm, on average, in the presence of damage. When the Fraunhofer MEVIS algorithm was instead used, registration errors decreased to 1.3 mm, on average, in the absence of damage and 2.5 mm, on average, when damage was present. This work demonstrated that the presence of lung tissue changes introduced following RT treatment for lung cancer can significantly decrease the registration accuracy achieved using deformable registration.

  16. (18)F-FDG-PET/CT, (123)I-MIBG and (99m)Tc-MDP whole-body scans, in detecting recurrence of an adult adrenal neuroblastoma.

    Science.gov (United States)

    Skoura, Evangelia; Oikonomopoulos, Georgios; Vasileiou, Spyridon; Kyprianou, Diogenis; Koumakis, Georgios; Datseris, Ioannis E

    2014-01-01

    Neuroblastoma is the most common extracranial solid malignancy in children, but is rare in adults. We report the case of a 33 year old man with recurrence of neuroblastoma, 2 years after the excision of the primary tumor in the right adrenal gland. The iodine-123-radioiodinated metaiodobenzylguanidine ((123)I-MIBG) and (99m)Tc-methylene diphosphonate ((99m)Tc-MDP) bone scans and the fluorine-18-fluorodeoxyglucose-positron computed tomography ((18)F-FDG PET/CT) findings in this patient are presented. First, we applied (123)I-MIBG scintigraphy that detected increased uptake at the right adrenal gland region and probably at liver lesions and in several bones. Then, the (99m)Tc-MDP bone scan revealed also increased uptake of the radiopharmaceutical in bones, but there was a discrepancy between these two studies concerning the number and location of the lesions. Then, (18)F-FDG PET/CT scan was performed, which showed increased uptake of (18)F-FDG at the right adrenal gland region with extension to the liver and also in multiple bones. Additionally, an aortocaval lymph node was detected. In conclusion, this case indicated that (18)F-FDG PET/CT has defined the extent of the recurrence of neuroblastoma in a better way than (123)I-MIBG and (99m)Tc-MDP together.

  17. Low-Dose and Scatter-Free Cone-Beam CT Imaging Using a Stationary Beam Blocker in a Single Scan: Phantom Studies

    Directory of Open Access Journals (Sweden)

    Xue Dong

    2013-01-01

    Full Text Available Excessive imaging dose from repeated scans and poor image quality mainly due to scatter contamination are the two bottlenecks of cone-beam CT (CBCT imaging. Compressed sensing (CS reconstruction algorithms show promises in recovering faithful signals from low-dose projection data but do not serve well the needs of accurate CBCT imaging if effective scatter correction is not in place. Scatter can be accurately measured and removed using measurement-based methods. However, these approaches are considered unpractical in the conventional FDK reconstruction, due to the inevitable primary loss for scatter measurement. We combine measurement-based scatter correction and CS-based iterative reconstruction to generate scatter-free images from low-dose projections. We distribute blocked areas on the detector where primary signals are considered redundant in a full scan. Scatter distribution is estimated by interpolating/extrapolating measured scatter samples inside blocked areas. CS-based iterative reconstruction is finally carried out on the undersampled data to obtain scatter-free and low-dose CBCT images. With only 25% of conventional full-scan dose, our method reduces the average CT number error from 250 HU to 24 HU and increases the contrast by a factor of 2.1 on Catphan 600 phantom. On an anthropomorphic head phantom, the average CT number error is reduced from 224 HU to 10 HU in the central uniform area.

  18. New Technique for Automatic Segmentation of Blood Vessels in CT Scan Images of Liver Based on Optimized Fuzzy C-Means Method

    Directory of Open Access Journals (Sweden)

    Katayoon Ahmadi

    2016-01-01

    Full Text Available Automatic segmentation of medical CT scan images is one of the most challenging fields in digital image processing. The goal of this paper is to discuss the automatic segmentation of CT scan images to detect and separate vessels in the liver. The segmentation of liver vessels is very important in the liver surgery planning and identifying the structure of vessels and their relationship to tumors. Fuzzy C-means (FCM method has already been proposed for segmentation of liver vessels. Due to classical optimization process, this method suffers lack of sensitivity to the initial values of ​​class centers and segmentation of local minima. In this article, a method based on FCM in conjunction with genetic algorithms (GA is applied for segmentation of liver’s blood vessels. This method was simulated and validated using 20 CT scan images of the liver. The results showed that the accuracy, sensitivity, specificity, and CPU time of new method in comparison with FCM algorithm reaching up to 91%, 83.62, 94.11%, and 27.17 were achieved, respectively. Moreover, selection of optimal and robust parameters in the initial step led to rapid convergence of the proposed method. The outcome of this research assists medical teams in estimating disease progress and selecting proper treatments.

  19. 18F-FDG PET/CT/MRI Fusion Images Showing Cranial and Peripheral Nerve Involvement in Neurolymphomatosis

    Science.gov (United States)

    Trevisan, Ana Carolina; Ribeiro, Fernanda Borges; Itikawa, Emerson Nobuyuki; Alexandre, Leonardo Santos; Pitella, Felipe Arriva; Santos, Antonio Carlos; Simões, Belinda Pinto; Wichert-Ana, Lauro

    2017-01-01

    We report a 56-year-old female patient with non-Hodgkin's diffuse large B cell lymphoma (NHL) who, on magnetic resonance imaging (MRI) with a T1 weighted and gadolinium-enhanced imaging, was found to have thickening and infiltration in 75% of peripheral nerves of the patient and enlargements of cranial nerves, possibly related to lymphomatous infiltration. Subsequent positron emission tomography/computed tomography (PET/CT) using 18F-labeled 2-deoxy-2-fluoro-d-glucose (18F-FDG) showed widespread active involvement of the cervical plexus, bilateral peripheral nerves, right femoral nerve, the parasellar region of the skull, and marked hypermetabolism in the left trigeminal ganglia. This case re-emphasizes that while CT and MRI provide anatomical details, 18F-FDG PET/CT images better delineate the metabolic activity of neurolymphomatosis (NL) in the peripheral and central nervous system.

  20. Thoracic CT-scans in ICU patients - Additional diagnostic information supplementing chest radiographs; Thorakale Computertomographie am Intensivpatienten - Zusatzinformation zum Thorax-Roentgen

    Energy Technology Data Exchange (ETDEWEB)

    Fuchsjaeger, M.; Hoermann, M.; Lechner, G.; Herold, C. [Vienna Univ. (Austria). Universitaetsklinik fuer Radiodiagnostik; Germann, P. [Vienna Univ. (Austria). Universitaetsklinik fuer Anaesthesiologie und Allgemeine Intensivmedizin

    2000-07-01

    To assess the diagnostic value of thoracic CT-scans in comparison with conventional chest radiographs in ICU-patients. Methods: Chest radiographs and corresponding thoracic CT-scans of 25 consecutive surgical ICU-patients were reviewed and interpreted independently by two radiologists. We analyzed the additional information provided by CT-scans and the diagnostic and therapeutic relevance of these findings. Results: In 22 patients (88%), thoracic CT revealed 35 single additional findings, in comparison with the corresponding bedside radiographs. In 7 cases (28%), these findings (tubemalpositioning, mediastinitis, mediastinal abscess and pneumothorax) required modification of patient management. Of 7 patients with tube thoracostomy, 3 tubes were malpositioned, which was only depicted on CT-scans. In 10 of 21 cases (48%), pleural effusions could only be visualized by CT. 3 of 5 (60%) pneumothoraces were detected by CT-scans only. There were no significant complications during transport or CT-examination. (orig.) [German] Ziel dieser Studie war die Definition des diagnostischen Zugewinns durch die thorakale Computertomographie (CT) gegenueber der Thoraxbettaufnahme am Intensivpatienten. Methodik: In einer vergleichenden Analyse wurden retrospektiv radiologische Aufnahmen und Daten von 25 konsekutiven Patienten einer chirurgischen Intensivstation ausgewertet. Ergebnisse: In 22 Faellen (88%) wurden durch die CT 35 zusaetzliche Befunde erhoben, wobei die haeufigsten Zusatzinformationen Pleura- und Perikarderguesse, Buelaudrainagefehllagen und Pneumothoraces betrafen. In 7 Faellen (28%) waren diese zusaetzlichen Informationen von intensivmedizinischer Relevanz, d.h., sie verlangten nach einer Intervention oder Aenderung der laufenden Therapie. Es kam zu keinerlei kardiovaskulaeren Komplikationen waehrend des Transportes oder der computertomographischen Untersuchung. (orig.)

  1. A novel method of estimating effective dose from the point dose method: a case study—parathyroid CT scans

    Science.gov (United States)

    Januzis, Natalie; Nguyen, Giao; Hoang, Jenny K.; Lowry, Carolyn; Yoshizumi, Terry T.

    2015-02-01

    The purpose of this study was to validate a novel approach of applying a partial volume correction factor (PVCF) using a limited number of MOSFET detectors in the effective dose (E) calculation. The results of the proposed PVCF method were compared to the results from both the point dose (PD) method and a commercial CT dose estimation software (CT-Expo). To measure organ doses, an adult female anthropomorphic phantom was loaded with 20 MOSFET detectors and was scanned using the non-contrast and 2 phase contrast-enhanced parathyroid imaging protocols on a 64-slice multi-detector computed tomography scanner. E was computed by three methods: the PD method, the PVCF method, and the CT-Expo method. The E (in mSv) for the PD method, the PVCF method, and CT-Expo method was 2.6  ±  0.2, 1.3  ±  0.1, and 1.1 for the non-contrast scan, 21.9  ±  0.4, 13.9  ±  0.2, and 14.6 for the 1st phase of the contrast-enhanced scan, and 15.5  ±  0.3, 9.8  ±  0.1, and 10.4 for the 2nd phase of the contrast-enhanced scan, respectively. The E with the PD method differed from the PVCF method by 66.7% for the non-contrast scan, by 44.9% and by 45.5% respectively for the 1st and 2nd phases of the contrast-enhanced scan. The E with PVCF was comparable to the results from the CT-Expo method with percent differences of 15.8%, 5.0%, and 6.3% for the non-contrast scan and the 1st and 2nd phases of the contrast-enhanced scan, respectively. To conclude, the PVCF method estimated E within 16% difference as compared to 50-70% in the PD method. In addition, the results demonstrate that E can be estimated accurately from a limited number of detectors.

  2. Fast Scatter Artifacts Correction for Cone-Beam CT without System Modification and Repeat Scan

    CERN Document Server

    Zhao, Wei; Wang, Luyao

    2015-01-01

    We provide a fast and accurate scatter artifacts correction algorithm for cone beam CT (CBCT) imaging. The method starts with an estimation of coarse scatter profile for a set of CBCT images. A total-variation denoising algorithm designed specifically for Poisson signal is then applied to derive the final scatter distribution. Qualitatively and quantitatively evaluations using Monte Carlo (MC) simulations, experimental CBCT phantom data, and \\emph{in vivo} human data acquired for a clinical image guided radiation therapy were performed. Results show that the proposed algorithm can significantly reduce scatter artifacts and recover the correct HU within either projection domain or image domain. Further test shows the method is robust with respect to segmentation procedure.

  3. Quantitative CT measurements of small pulmonary vessels in chronic obstructive pulmonary disease: do they change on follow-up scans?

    Science.gov (United States)

    Saruya, Shinji; Matsuoka, Shin; Yamashiro, Tsuneo; Matsushita, Shoichiro; Fujikawa, Atsuko; Yagihashi, Kunihiro; Kurihara, Yasuyuki; Nakajima, Yasuo

    2016-05-01

    The aims of this study were to perform a longitudinal evaluation of the cross-sectional area (CSA) of small pulmonary vessels and the extent of emphysema measured on computed tomography (CT) scans of patients with chronic obstructive pulmonary disease (COPD), and to correlate the pulmonary vascular measurements with extent of emphysema. The institutional review board approved this retrospective study and waived the need for patients' informed consent. Seventy-four patients with COPD who underwent both initial and follow-up CT scans at an interval of ≥12 months were analysed. The CSA of small pulmonary vessels up measurements were performed using the Wilcoxon signed-rank test. The relationship between longitudinal changes in %CSAup period was assessed using the Spearman rank correlation. The %LAA increased significantly on follow-up CT scans (Pup scans, but the difference was not significant. Although longitudinal change in %LAA was positively correlated with duration of follow-up period (ρ = 0·505, P<0·0001), longitudinal change in %CSA<5 was not. In conclusion, there was a progressive increase in the extent of emphysema over time, but no significant decrease in the CSA of small pulmonary vessels over the same time period.

  4. Assessment of the increased calcification of the jaw bone with CT-Scan after dental implant placement

    Energy Technology Data Exchange (ETDEWEB)

    Yunus, Barunawaty [Faculty of Dentistry, Hasanuddin University, Makassar (Malaysia)

    2011-06-15

    This study was performed to evaluate the changes of jaw bone density around the dental implant after placement using computed tomography scan (CT-Scan). This retrospective study consisted of 30 patients who had lost 1 posterior tooth in maxilla or mandible and installed dental implant. The patients took CT-Scan before and after implant placement. Hounsfield Unit (HU) was measured around the implants and evaluated the difference of HU before and after implant installation. The mean HU of jaw bone was 542.436 HU and 764.9 HU before and after implant placement, respectively (p<0.05). The means HUs for male were 632.3 HU and 932.2 HU and those for female 478.2 HU and 645.5 HU before and after implant placement, respectively (p<0.05). Also, the jaw bone with lower density needed longer period for implant procedure and the increased change of HU of jaw bone was less in the cases which needed longer period for osseointegration. CT-Scan could be used to assess the change of bone density around dental implants. Bone density around dental implant was increased after placement. The increased rate of bone density could be determined by the quality of jaw bone before implant placement.

  5. 螺旋 CT动态增强扫描在肺门肿瘤立体适形放射治疗中的价值%The value of spiral CT dynamically enhanced scanning in steric shape-fitting radiotherapy of hilar tumors

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To judge hilar tumors and their involvement range and improve the ability for the 3D plan of steric shape- fitting radiotherapy of pulmonary cancer dicide target area.Method Spiral CT dynamically enhanced scanning was used to localize the target area and distinguish pilar tumors,atelactasis,pilar blood vessels and enlarged lymphoid tissues,and define locus and involvement area.Result Local contour showed by spiral CT enhanced dynamically scanning was superior to that by common CT.Conclusion Spiral CT dynamically enhanced scanning is an ideal simulation for 3D conformal radiotherapy.

  6. Frequency, Causes, and Findings of Brain CT Scans of Neonatal Seizure at Besat Hospital, Hamadan, Iran

    Directory of Open Access Journals (Sweden)

    Fateme EGHBALIAN*

    2015-01-01

    Full Text Available How to Cite This Article: Eghbalian F, Rasuli B, Monsef F. Frequency, Causes, and Findings of Brain CT Scans of Neonatal Seizure at Besat Hospital, Hamadan, Iran. Iran J Child Neurol. 2015 Winter;9(1:56-63.AbstractObjectiveNeonatal seizures are the most common neurological symptoms and often signal an underlying serious neurologic condition. This study determines the frequency of neonatal seizure, predisposing factors, and brain computed tomography (CT scan findings.Materials & MethodsIn a descriptive cross-sectional study, we evaluated all neonates with seizures who had been hospitalized in Besat hospital from 2007–2012. All data were gathered with questionnaires and used to compare with statistical tests by SPSS (ver 16. Results141 (4.08% neonates (M:F; 1:2.2 were diagnosed with neonatal seizures. From the total number of 3,452 neonatal hospitalization, 78% of neonates with seizures were less than 10 days old and 60.3% of infants were born from natural vaginal delivery. As the most common cause, hypoxic-ischemic encephalopathy in this study was associated with 31.3% (n=44 of neonatal seizures and with the highest mortality rate (n=6. Among admitted neonates with seizures, the overall mortality rate was 12.8% (18 cases. A total of 33.3% of patients (47 cases had abnormal CT scan reports and 24.8% (35 cases of patients were not evaluated with a CT scan. Hypoxic-ischemic encephalopathy (47% and local ischemic changes (25.5% were the most common findings in the CT scans of neonates with seizures.ConclusionThere was a significant correlation between neonatal seizures and delivery circumstances (p-value < 0.05. Therefore, with improvement of obstetric and delivery circumstances, early detection of predisposing factors and other rare conditions, and rapid effective treatment of these contributing factors, the rate of neonatal seizure in this period can be reduced.ReferencesScher MS. Seizure in the newborn infant: diagnosis, treatment, and outcome

  7. Offline RF thermal ablation planning using CT/MRI scan data

    Directory of Open Access Journals (Sweden)

    Md. Faruk Ali

    2015-03-01

    Full Text Available In this paper, steady state temperature variations in the human brain due to different electrical and physical changes have been studied considering different thermal ablation treatment requirements using RF probe. Initially, a subject specific voxel-based electrical model has been constructed from Digital Imaging and Communication in Medicine (DICOM formatted Computed Tomography (CT or Magnetic Resonance (MR based image stacks with different pixel characteristics using the Hounsfield unit extraction technique. This subject specific electrical model that consists of different dielectric constant and conductivity, considering different anatomical organs and tissues is simulated using commercially available finite integral technique (FIT based EM simulation software CST Microwave Studio®. This study clearly shows the possibility of subject specific precise offline microwave thermal ablation treatment planning.

  8. Automatic intrinsic cardiac and respiratory gating from cone-beam CT scans of the thorax region

    Science.gov (United States)

    Hahn, Andreas; Sauppe, Sebastian; Lell, Michael; Kachelrieß, Marc

    2016-03-01

    We present a new algorithm that allows for raw data-based automated cardiac and respiratory intrinsic gating in cone-beam CT scans. It can be summarized in three steps: First, a median filter is applied to an initially reconstructed volume. The forward projection of this volume contains less motion information and is subtracted from the original projections. This results in new raw data that contain only moving and not static anatomy like bones, that would otherwise impede the cardiac or respiratory signal acquisition. All further steps are applied to these modified raw data. Second, the raw data are cropped to a region of interest (ROI). The ROI in the raw data is determined by the forward projection of a binary volume of interest (VOI) that includes the diaphragm for respiratory gating and most of the edge of the heart for cardiac gating. Third, the mean gray value in this ROI is calculated for every projection and the respiratory/cardiac signal is acquired using a bandpass filter. Steps two and three are carried out simultaneously for 64 or 1440 overlapping VOI inside the body for the respiratory or cardiac signal respectively. The signals acquired from each ROI are compared and the most consistent one is chosen as the desired cardiac or respiratory motion signal. Consistency is assessed by the standard deviation of the time between two maxima. The robustness and efficiency of the method is evaluated using simulated and measured patient data by computing the standard deviation of the mean signal difference between the ground truth and the intrinsic signal.

  9. Multidrug resistant tuberculosis versus non-tuberculous mycobacterial infections: a CT-scan challenge

    Energy Technology Data Exchange (ETDEWEB)

    Kahkouee, Shahram; Esmi, Elham; Moghadam, Azadeh; Karam, Mehrdad Bakhshayesh; Mosadegh, Leila; Salek, Solmaz; Tabarsi, Payam, E-mail: bestlala@yahoo.com [Chronic Respiratory Disease Research Center, NRITLD, Masih Daneshvari Hospital, Shahid Beheshti University of Medical Science, Tehran (Iran, Islamic Republic of)

    2013-03-15

    Introduction: clinical, laboratory and imaging findings in patients with multidrug resistant tuberculosis (MDR-TB) and non-tuberculosis mycobacterium (NTM) are similar, and the majority of these patients present with positive smear for Acid Fast Bacilli (ADB) and no response to first line anti-TB treatment, so sputum culture and PCR are necessary, especially in NTM. Objective: In this study we evaluate more details of imaging findings to help earlier diagnosis of pathogens. Materials and methods: 66 patients with positive smear for AFB and no response to first line anti-TB drugs were divided into two groups by PCR and culture: MDR-TB (43 patients) and NTM (23 patients). Age, sex, history of anti-TB treatment, smoking and CT-scan findings (parenchymal, pleural and mediastinal variables) by details and lobar distribution were analyzed. Results: mean age of NTM patients was slightly higher (52 versus 45) and there is no significant difference in sex and smoking. In MDR-TB group, history of anti-TB treatment and evidence of chronic pulmonary disease such as calcified and fibrodestructed parenchyma, volume loss and pleural thickening were higher significantly. Cavities in MDR-TB were thick wall in the background of consolidation, while NTM cavities were more thin-walled with adjacent satellite nodules in same segment or lobe. Prevalence of bronchiectasis was similar in both groups, while bronchiectasis in MDR-TB group was in fibrobronchiectatic background in upper lobes, and in NTM group the distribution was more uniform with slightly middle lobes predominance. Prevalence and distribution of nodular infiltrations were similar more in Tree in Buds and scattered pattern. Calcified or non-calcified lymph nodes and also pleural changes were more frequent in MDR-TB but prevalence of lymphadenopathy was mildly higher in NTM. (author)

  10. Assessment of the Impact of Zoledronic Acid on Ovariectomized Osteoporosis Model Using Micro-CT Scanning.

    Directory of Open Access Journals (Sweden)

    Bo Shuai

    Full Text Available Prompted by preliminary findings, this study was conducted to investigate the impact of zoledronic acid on the cancellous bone microstructure and its effect on the level of β-catenin in a mouse model of postmenopausal osteoporosis.96 8-week-old specific-pathogen-free C57BL/6 mice were randomly divided into 4 groups (24 per group: a sham group, an ovariectomized osteoporosis model group, an estradiol-treated group, and a zoledronic acid-treated group. Five months after surgery, the third lumbar vertebra and left femur of the animals were dissected and scanned using micro-computed tomography (micro-CT to acquire three-dimensional imagery of their cancellous bone microstructure. The impact of ovariectomy, the effect of estradiol, and the effect of zoledronic acid intervention on cancellous bone microstructure, as well as on the expression of β-catenin, were evaluated.The estradiol-treated and the zoledronic acid-treated group exhibited a significant increase in the bone volume fraction, trabecular number, trabecular thickness, bone surface to bone volume ratio (BS/BV, and β-catenin expression, when compared with those of the control group (P <0.01. In contrast, the structure model index, trabecular separation, and BS/BV were significantly lower compared with those of the model group (P <0.01. No differences were observed in the above parameters between animals of the zoledronic acid-treated and the estradiol-treated group.These results suggest that increased β-catenin expression may be the mechanism underlying zoledronic acid-related improvement in the cancellous bone microstructure in ovariectomized mice. Our findings provide a scientific rationale for using zoledronic acid as a therapeutic intervention to prevent bone loss in post-menopausal women.

  11. Multidrug resistant tuberculosis versus non-tuberculous mycobacterial infections: a CT-scan challenge

    Directory of Open Access Journals (Sweden)

    Shahram Kahkouee

    Full Text Available INTRODUCTION: Clinical, laboratory and imaging findings in patients with multidrug resistanttuberculosis (MDR-TB and non-tuberculosis mycobacterium (NTM are similar, and the majority of these patients present with positive smear for Acid Fast Bacilli (ADB and no response to first line anti-TB treatment, so sputum culture and PCR are necessary, especially in NTM. OBJECTIVE: In this study we evaluate more details of imaging findings to help earlier diagnosis of pathogens. MATERIALS AND METHODS: 66 patients with positive smear for AFB and no response to first line anti-TB drugs were divided into two groups by PCR and culture: MDR-TB (43 patients and NTM (23 patients. Age, sex, history of anti-TB treatment, smoking and CT-scan findings (parenchymal, pleural and mediastinal variables by details and lobar distribution were analyzed. RESULTS: Mean age of NTM patients was slightly higher (52 versus 45 and there is no significant difference in sex and smoking. In MDR-TB group, history of anti-TB treatment and evidence of chronic pulmonary disease such as calcified and fibrodestructed parenchyma, volume loss and pleural thickening were higher significantly. Cavities in MDR-TB were thickwall in the background of consolidation, while NTM cavities were more thin-walled with adjacent satellite nodules in same segment or lobe. Prevalence of bronchiectasis was similar in both groups, while bronchiectasis in MDR-TB group was in fibrobronchiectatic background in upper lobes, and in NTM group the distribution was more uniform with slightly middle lobes predominance. Prevalence and distribution of nodular infiltrations were similar more in Tree in Buds and scattered pattern. Calcified or non-calcified lymph nodes and also pleural changes were more frequent in MDR-TB but prevalence of lymphadenopathy was mildly higher in NTM. CONCLUSION: A check-list with multiple variables is helpful for differentiation between the two groups.

  12. Multidrug resistant tuberculosis versus non-tuberculous mycobacterial infections: a CT-scan challenge

    Directory of Open Access Journals (Sweden)

    Shahram Kahkouee

    2013-04-01

    Full Text Available INTRODUCTION: Clinical, laboratory and imaging findings in patients with multidrug resistanttuberculosis (MDR-TB and non-tuberculosis mycobacterium (NTM are similar, and the majority of these patients present with positive smear for Acid Fast Bacilli (ADB and no response to first line anti-TB treatment, so sputum culture and PCR are necessary, especially in NTM. OBJECTIVE: In this study we evaluate more details of imaging findings to help earlier diagnosis of pathogens. MATERIALS AND METHODS: 66 patients with positive smear for AFB and no response to first line anti-TB drugs were divided into two groups by PCR and culture: MDR-TB (43 patients and NTM (23 patients. Age, sex, history of anti-TB treatment, smoking and CT-scan findings (parenchymal, pleural and mediastinal variables by details and lobar distribution were analyzed. RESULTS: Mean age of NTM patients was slightly higher (52 versus 45 and there is no significant difference in sex and smoking. In MDR-TB group, history of anti-TB treatment and evidence of chronic pulmonary disease such as calcified and fibrodestructed parenchyma, volume loss and pleural thickening were higher significantly. Cavities in MDR-TB were thickwall in the background of consolidation, while NTM cavities were more thin-walled with adjacent satellite nodules in same segment or lobe. Prevalence of bronchiectasis was similar in both groups, while bronchiectasis in MDR-TB group was in fibrobronchiectatic background in upper lobes, and in NTM group the distribution was more uniform with slightly middle lobes predominance. Prevalence and distribution of nodular infiltrations were similar more in Tree in Buds and scattered pattern. Calcified or non-calcified lymph nodes and also pleural changes were more frequent in MDR-TB but prevalence of lymphadenopathy was mildly higher in NTM. CONCLUSION: A check-list with multiple variables is helpful for differentiation between the two groups.

  13. Top-level Design and Pilot Analysis of Low-end CT Scanners Based on Linear Scanning for Developing Countries

    CERN Document Server

    Liu, Fenglin; Cong, Wenxiang; Wang, Ge

    2013-01-01

    Purpose: The goal is to develop a new architecture for computed tomography (CT) which is at an ultra-low-dose for developing countries, especially in rural areas. Methods: The proposed scheme is inspired by the recently developed compressive sensing and interior tomography techniques, where the data acquisition system targets a region of interest (ROI) to acquire limited and truncated data. The source and detector are translated in opposite directions for either ROI reconstruction with one or more localized linear scans or global reconstruction by combining multiple ROI reconstructions. In other words, the popular slip ring is replaced by a translation based setup, and the instrumentation cost is reduced by a relaxation of the imaging speed requirement. Results: The various translational scanning modes are theoretically analyzed, and the scanning parameters are optimized. The numerical simulation results from different numbers of linear scans confirm the feasibility of the proposed scheme, and suggest two pre...

  14. Burden of subclinical heart and lung disease detected on thoracic CT scans of HIV patients on HAART

    Directory of Open Access Journals (Sweden)

    Stefano Zona

    2014-11-01

    Full Text Available Introduction: The aim was to determine the prevalence of lung and heart abnormalities on thoracic CT scans in HIV-infected patients who were treated with antiretroviral therapy (ART. Material and Methods: Thoracic CT scans of 903 patients infected with HIV (mean age 48±7 yrs, 29% females were reviewed by three radiologists by consensus. Patients were phenotyped according to smoking status, pack years and years since cessation for ex-smokers. Individuals known to have active lung or heart disease at the time of CT scanning were excluded. Multimorbidity lung and heart disease (MLHD was defined by the presence of >2 lung or heart abnormalities on the CT scan. Results: Prevalence of lung abnormalities were: 326 patients (36.1% with emphysema, 271 (30.0% with bronchiolitis, 44 (4.9% with non-calcified lung nodules, 568 (63% with significant bronchial wall thickening, 150 (16.7% with bronchiectasis, 9 (1% with interstitial lung disease. Overall, 445 patients (49.3% had >2 lung abnormalities. Imaging findings suggestive of prior myocardial infarction (MI were found in 1.4% (13 patients; 26.6% (240 patients had CAC scores of 1 to 100, and 9.8% (89 patients had CAC>100. 13.6% (123 patients of the patients had CAC>100 and/or previous MI. MLHD was present in 484 patients (53.6% and among 78 patients (16% who never smoked. Table 1 describes CT findings according to pack year and stop smoking groups vs never smokers.MLHD increased proportional to cumulative smoking history (p for trend <0.001 and decreased in proportion to the number of years since smoking cessation (p for trend=0.017. Independent predictors for MLHD were: age (OR=1.07, CI 1.05–1.10, sex (OR=1.59, CI 1.15–2.19, current smoking (OR=1.76, CI 1.08–2.89, and pack-years history of smoking (OR=1.03, CI 1.02–1.05. In patients who never smoked, nadir CD4<200 was significantly associated with MLHD after adjustment for age and sex (OR=1.98, CI 1.98–3.63. Conclusions: MLHD is common in HIV

  15. Improved image quality of cone beam CT scans for radiotherapy image guidance using fiber-interspaced antiscatter grid

    Energy Technology Data Exchange (ETDEWEB)

    Stankovic, Uros; Herk, Marcel van; Ploeger, Lennert S.; Sonke, Jan-Jakob, E-mail: j.sonke@nki.nl [Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam 1066 CX (Netherlands)

    2014-06-15

    Purpose: Medical linear accelerator mounted cone beam CT (CBCT) scanner provides useful soft tissue contrast for purposes of image guidance in radiotherapy. The presence of extensive scattered radiation has a negative effect on soft tissue visibility and uniformity of CBCT scans. Antiscatter grids (ASG) are used in the field of diagnostic radiography to mitigate the scatter. They usually do increase the contrast of the scan, but simultaneously increase the noise. Therefore, and considering other scatter mitigation mechanisms present in a CBCT scanner, the applicability of ASGs with aluminum interspacing for a wide range of imaging conditions has been inconclusive in previous studies. In recent years, grids using fiber interspacers have appeared, providing grids with higher scatter rejection while maintaining reasonable transmission of primary radiation. The purpose of this study was to evaluate the impact of one such grid on CBCT image quality. Methods: The grid used (Philips Medical Systems) had ratio of 21:1, frequency 36 lp/cm, and nominal selectivity of 11.9. It was mounted on the kV flat panel detector of an Elekta Synergy linear accelerator and tested in a phantom and a clinical study. Due to the flex of the linac and presence of gridline artifacts an angle dependent gain correction algorithm was devised to mitigate resulting artifacts. Scan reconstruction was performed using XVI4.5 augmented with inhouse developed image lag correction and Hounsfield unit calibration. To determine the necessary parameters for Hounsfield unit calibration and software scatter correction parameters, the Catphan 600 (The Phantom Laboratory) phantom was used. Image quality parameters were evaluated using CIRS CBCT Image Quality and Electron Density Phantom (CIRS) in two different geometries: one modeling head and neck and other pelvic region. Phantoms were acquired with and without the grid and reconstructed with and without software correction which was adapted for the different

  16. Image-based compensation for involuntary motion in weight-bearing C-arm cone-beam CT scanning of knees

    Science.gov (United States)

    Unberath, Mathias; Choi, Jang-Hwan; Berger, Martin; Maier, Andreas; Fahrig, Rebecca

    2015-03-01

    We previously introduced four fiducial marker-based strategies to compensate for involuntary knee-joint motion during weight-bearing C-arm CT scanning of the lower body. 2D methods showed significant reduction of motion- related artifacts, but 3D methods worked best. However, previous methods led to increased examination times and patient discomfort caused by the marker attachment process. Moreover, sub-optimal marker placement may lead to decreased marker detectability and therefore unstable motion estimates. In order to reduce overall patient discomfort, we developed a new image-based 2D projection shifting method. A C-arm cone-beam CT system was used to acquire projection images of five healthy volunteers at various flexion angles. Projection matrices for the horizontal scanning trajectory were calibrated using the Siemens standard PDS-2 phantom. The initial reconstruction was forward projected using maximum-intensity projections (MIP), yielding an estimate of a static scan. This estimate was then used to obtain the 2D projection shifts via registration. For the scan with the most motion, the proposed method reproduced the marker-based results with a mean error of 2.90 mm +/- 1.43 mm (compared to a mean error of 4.10 mm +/- 3.03 mm in the uncorrected case). Bone contour surrounding modeling clay layer was improved. The proposed method is a first step towards automatic image-based, marker-free motion-compensation.

  17. CT scanning of the brain and lumbar CSF monoamine metabolites in spinocerebellar degenerative disorders

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Hidenao; Kanazawa, Ichiro; Nakanishi, Takao; Kuramoto, Kenmei (Tsukuba Univ., Sakura, Ibaraki (Japan))

    1984-08-01

    Eight patients with parenchymatous cerebellar degeneration (PCD) group (3 with late cortical cerebellar atrophy and 5 with Holmes' hereditary ataxia), 14 with olivo-ponto-cerebellar atrophy (OPCA) group (4 with Shy-Drager syndrome, 6 with OPCA without family history and 4 with Menzel type SCS), 15 with Parkinson's disease and 44 control with other neurological diseases were studied. In all the spinocerebellar degenerative disorders (SCD) cases, CVI values corresponding to the cerebellar atrophy were definitely reduced. On the other hand, PVI values corresponding to the pontine atrophy were only significantly decreased in OPCA group. However, since there were several cases showing only questionable pontine atrophy, it seems difficult to clearly differentiate individual OPCA cases from other SCD cases on CT films alone. Concerning monoamine metabolites in CSF, it was noted that a significant reduction of HVA and total MHPG was found in the OPCA group. Among them, the patients with overt autonomic failure showed the lowest HVA level and the cases of Menzel type of SCD showed a slight reduction of HVA but an unexpected elevation of free MHPG values. The cases of Parkinson's disease showed a definite reduction of HVA. On the other hand, the cases of PCD group showed no significant difference against controls. 5-HIAA levels were not significantly different among the SCD subgroups.

  18. CT scan suggesting lesions of the both lateral geniculate bodies and the calcarine corteces in a case of traumatic blindness

    Energy Technology Data Exchange (ETDEWEB)

    Mizoi, K.; Nishijima, M. (Tohoku Univ., Sendai (Japan). Shool of Medicine); Onuma, T.

    1981-09-01

    A 29-year-old man fell down the stairs and suffered impact in the left temporo-parietal region. On the following day, although he was stuporous, motor disturbances and anisocoria were not observed, and both pupils normally reacted to light. Carotid angiography showed an avascular area in the left temporal area. Four days after the head injury he showed a generalized tonic-clonic convulsion. He became semicomatose with dilatation of bilateral pupils and decerebrate rigidity of all extremities. An immediate craniotomy was carried out and 100 g. of epidural hematoma was removed. He became fully conscious 6 days after the operation, and he complained of blindness. A CT scan performed 15 days after the operation revealed low density areas occupying the bilateral lateral geniculate bodies and the visual corteces, and these areas were enhanced by contrast medium. These lesions were diagnosed as infarction caused by compression of the posterior cerebral arteries resulting from tentorial herniation. This is the first case reported in the literature.

  19. Top-level design and pilot analysis of low-end CT scanners based on linear scanning for developing countries.

    Science.gov (United States)

    Liu, Fenglin; Yu, Hengyong; Cong, Wenxiang; Wang, Ge

    2014-01-01

    The goal is to develop new architectures for computed tomography (CT) which are at an ultra-low-cost for developing countries, especially in rural areas. The proposed general scheme is inspired by the recently developed compressive sensing and interior tomography techniques, where the data acquisition system targets a region of interest (ROI) to acquire limited and truncated data. Similar to linear tomosynthesis, the source and detector are translated in opposite directions but in contrast to conventional tomosynthesis, our proposal is for either ROI reconstruction with one or more localized linear scans or global reconstruction by combining multiple ROI reconstructions. In other words, the popular slip ring is replaced by a translation based setup, and the instrumentation cost is reduced by a relaxation of the imaging speed requirement. The various translational scanning modes are theoretically analyzed, and the scanning parameters are optimized. The numerical simulation results from different numbers of linear scans confirm the feasibility of the proposed scheme, and suggest two preferred low-end systems for horizontal and vertical patient positions respectively. Ultra-low-cost x-ray CT is feasible with our proposed combination of linear scanning, compressive sensing, and interior tomography. The proposed architecture can be tailored into permanent, movable, or reconfigurable systems as desirable. Advanced image registration and spectral imaging features can be included as well.

  20. Measurements of Epidural Space Depth Using Preexisting CT Scans Correlate with Loss of Resistance Depth during Thoracic Epidural Catheter Placement

    Directory of Open Access Journals (Sweden)

    Nathaniel H. Greene

    2015-01-01

    Full Text Available Background. Thoracic epidural catheters provide the best quality postoperative pain relief for major abdominal and thoracic surgical procedures, but placement is one of the most challenging procedures in the repertoire of an anesthesiologist. Most patients presenting for a procedure that would benefit from a thoracic epidural catheter have already had high resolution imaging that may be useful to assist placement of a catheter. Methods. This retrospective study used data from 168 patients to examine the association and predictive power of epidural-skin distance (ESD on computed tomography (CT to determine loss of resistance depth acquired during epidural placement. Additionally, the ability of anesthesiologists to measure this distance was compared to a radiologist, who specializes in spine imaging. Results. There was a strong association between CT measurement and loss of resistance depth (P35 changed this relationship (P=0.007. The ability of anesthesiologists to make CT measurements was similar to a gold standard radiologist (all individual ICCs>0.9. Conclusions. Overall, this study supports the examination of a recent CT scan to aid in the placement of a thoracic epidural catheter. Making use of these scans may lead to faster epidural placements, fewer accidental dural punctures, and better epidural blockade.

  1. Influence of hypodermic needle dimensions on subcutaneous injection delivery--a pig study of injection deposition evaluated by CT scanning, histology, and backflow.

    Science.gov (United States)

    Juul, Kezia Ann Praestmark; Bengtsson, Henrik; Eyving, Bente; Kildegaard, Jonas; Lav, Steffen; Poulsen, Mette; Serup, Jørgen; Stallknecht, Bente

    2012-11-01

    Thinner and shorter needles for subcutaneous administration are continuously developed. Previous studies have shown that a thinner needle causes fewer occurrences of painful needle insertions and that a shorter needle decreases the occurrence of painful intramuscular injections. However, little is known about local drug delivery in relation to needle length and thickness. This study aimed to compare deposition depth and backflow from three hypodermic needles of 3 mm 34G (0.19 mm), 5 mm 32G (0.23 mm), and 8 mm 30G (0.30 mm) in length and thickness. Ex vivo experiments were carried out on pigs, in neck tissue comparable to human skin at typical injection sites. Six pigs were included and a total of 72 randomized injections were given, i.e. 24 subcutaneous injections given with each needle type. Accordingly, 400 μL was injected including 70% NovoRapid(®) (Novo Nordisk A/S, Bagsvμrd, Denmark) and 30% Xenetix(®) (Guerbet, Villepinte, France) contrast including 1 mg/mL Alcian blue. Surgical biopsies of injection sites were sampled and computer topographic (CT)-scanned in 3D to assess deposition and local distribution. Biopsies were prepared and stained to evaluate deposition in comparison to the CT-scanning findings. The backflow of each injection was collected with filter paper. The blue stains of filter paper were digitized and volume estimated by software calculation vs. control staining. CT-scanning (n = 57) and histology (n = 10) showed that, regardless of injection depth, the bulk of the injection was in the subcutaneous tissue and did not propagate from subcutis into dermis. With the 8 mm 30G needle all injections apart from one intramuscular injection were located in the subcutaneous layer. The volume depositions peaked in 4-5 mm depth for the 3 mm 34G needle, in 5-6 mm depth for the 5 mm 32G needle, and in 9-10 mm depth for the 8 mm 30G needle. In general, injection depositions evaluated by histology and CT-scans compared well for the individual biopsies

  2. Coronary calcium score scans for attenuation correction of quantitative PET/CT {sup 13}N-ammonia myocardial perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Burkhard, Nina; Herzog, Bernhard A.; Husmann, Lars; Pazhenkottil, Aju P.; Burger, Irene A.; Buechel, Ronny R.; Valenta, Ines; Wyss, Christophe A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); Kaufmann, Philipp A. [University Hospital Zurich, Cardiac Imaging, Zurich (Switzerland); University of Zurich, Zurich Center for Integrative Human Physiology, Zurich (Switzerland)

    2010-03-15

    The aim of this study was to evaluate whether ECG-triggered coronary calcium scoring (CCS) scans can be used for attenuation correction (AC) to quantify myocardial blood flow (MBF) and coronary flow reserve (CFR) assessed by PET/CT with {sup 13}N-ammonia. Thirty-five consecutive patients underwent a {sup 13}N-ammonia PET/CT scan at rest and during standard adenosine stress. MBF values were calculated using AC maps obtained from the ECG-triggered CCS scan during inspiration and validated against MBF values calculated using standard non-gated transmission scans for AC. CFR was calculated as the ratio of hyperaemic over resting MBF. In all 35 consecutive patients intraobserver variability was assessed by blinded repeat analysis for both AC methods. There was an excellent correlation between CT AC and CCS for global MBF values at rest (n = 35, r = 0.94, p < 0.001) and during stress (n = 35, r = 0.97, p < 0.001) with narrow Bland-Altman (BA) limits of agreement (-0.21 to 0.10 ml/min per g and -0.41 to 0.30 ml/min per g) as well as for global CFR (n = 35, r = 0.96, p < 0.001, BA -0.27 to 0.34). The excellent correlation was preserved on the segmental MBF analysis for both rest and stress (n = 1190, r = 0.93, p < 0.001, BA -0.60 to 0.50) and for CFR (n = 595, r = 0.87, p < 0.001, BA -0.71 to 0.74). In addition, reproducibility proved excellent for global CFR by CT AC (n = 35, r = 0.91, p < 0.001, BA -0.42-0.58) and CCS scans (n = 35, r = 0.94, p < 0.001, BA -0.34-0.45). Use of attenuation maps from CCS scans allows accurate quantitative MBF and CFR assessment with {sup 13}N-ammonia PET/CT. (orig.)

  3. (18)F-Choline PET/CT scan in staging and biochemical recurrence in prostate cancer patients: Changes in classification and radiotherapy planning.

    Science.gov (United States)

    Cardona Arboniés, J; Rodríguez Alfonso, B; Mucientes Rasilla, J; Martínez Ballesteros, C; Zapata Paz, I; Prieto Soriano, A; Carballido Rodriguez, J; Mitjavila Casanovas, M

    To evaluate the role of the (18)F-Choline PET/CT in prostate cancer management when detecting distant disease in planning radiotherapy and staging and to evaluate the therapy changes guided by PET/TC results. A retrospective evaluation was performed on (18)F-Choline PET/CT scans of patients with prostate cancer. Staging and planning radiotherapy scans were selected in patients with at least 9 months follow up. There was a total of 56 studies, 33 (58.93%) for staging, and 23 (41.07%) for planning radiotherapy. All scans were obtained using a hybrid PET/CT scanner. The PET/CT acquisition protocol consisted of a dual-phase procedure after the administration of an intravenous injection of 296-370MBq of (18)F-Choline. There were 43 out of 56 (76.8%) scans considered as positive, and 13 (23.2%) were negative. The TNM staging was changed in 13 (23.2%) scans. The PET/CT findings ruled out distant disease in 4 out of 13 scans, and unknown distant disease was detected in 9 (69.3%) scans. (18)F-Choline PET/CT is a useful technique for detecting unknown distant disease in prostate cancer when staging and planning radiotherapy. The inclusion of (18)F-choline PET/CT should be considered in prostate cancer management protocols. Copyright © 2017 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

  4. Improving the quality of reconstructed X-ray CT images of polymer gel dosimeters: zero-scan coupled with adaptive mean filtering.

    Science.gov (United States)

    Kakakhel, M B; Jirasek, A; Johnston, H; Kairn, T; Trapp, J V

    2017-02-06

    This study evaluated the feasibility of combining the 'zero-scan' (ZS) X-ray computed tomography (CT) based polymer gel dosimeter (PGD) readout with adaptive mean (AM) filtering for improving the signal to noise ratio (SNR), and to compare these results with available average scan (AS) X-ray CT readout techniques. NIPAM PGD were manufactured, irradiated with 6 MV photons, CT imaged and processed in Matlab. AM filter for two iterations, with 3 × 3 and 5 × 5 pixels (kernel size), was used in two scenarios (a) the CT images were subjected to AM filtering (pre-processing) and these were further employed to generate AS and ZS gel images, and (b) the AS and ZS images were first reconstructed from the CT images and then AM filtering was carried out (post-processing). SNR was computed in an ROI of 30 × 30 for different pre and post processing cases. Results showed that the ZS technique combined with AM filtering resulted in improved SNR. Using the previously-recommended 25 images for reconstruction the ZS pre-processed protocol can give an increase of 44% and 80% in SNR for 3 × 3 and 5 × 5 kernel sizes respectively. However, post processing using both techniques and filter sizes introduced blur and a reduction in the spatial resolution. Based on this work, it is possible to recommend that the ZS method may be combined with pre-processed AM filtering using appropriate kernel size, to produce a large increase in the SNR of the reconstructed PGD images.

  5. Crossed Fused Renal Ectopia: Presentations on 99mTc-MAG3 Scan, 99mTc-DMSA SPECT, and Multidetector CT.

    Science.gov (United States)

    Moon, Eun Ha; Kim, Min-Woo; Kim, Young Jun; Sun, In O

    2015-10-01

    Crossed renal ectopia is an uncommon developmental anomaly in which both kidneys are located on the same side of the body. The present case describes a 20-year-old man who underwent the military entrance physical examination. The ultrasound showed the right kidney in normal site with slightly increased size, but the left kidney was not identified. Tc-MAG3 scan showed a single kidney with 2 ureters, and the orifices of the ureters were connected at both sides of bladder. Tc-DMSA SPECT and contrast-enhanced multidetector CT were performed and revealed crossed fused renal ectopia.

  6. Dynamic CT Scan of the Normal Scapholunate Joint in a Clenched Fist and Radial and Ulnar Deviation.

    Science.gov (United States)

    Kelly, Paul M; Hopkins, John G; Furey, Andrew J; Squire, Daniel S

    2017-08-01

    Injuries to the scapholunate can have severe long-term effects on the wrist. Early detection of these injuries can help identify pathology. The purpose of this study was to evaluate the motions of the scapholunate joint in normal wrists in a clenched fist and through radial and ulnar deviation using novel dynamic computed tomography (CT) imaging. Fifteen participants below 40 years of age consented to have their wrist scanned. Eight participants were randomized to have the right wrist scanned and 7 the left wrist. Volunteers were positioned at the back of the gantry with the wrist placed on the table, palmar side down. Participants began with the hand in a relaxed fist position and then proceeded through an established range of motion protocol. Dynamic CT imaging was captured throughout the range of motion. The movement in the healthy scapholunate joint through a clenched fist and radial and ulnar deviation is minimal. The averages were 1.19, 1.01, and 0.95 mm, representing the middle, dorsal, and volar measurements, respectively. This novel dynamic CT scan of the wrist is a user-friendly way of measuring of the scapholunate distance, which is minimal in the normal wrist below 40 years of age.

  7. Evaluation of radiation dose of triple rule-out coronary angiography protocols with different scan length using 256-slice CT

    Science.gov (United States)

    Tsai, Chia-Jung; Lee, Jason J. S.; Chen, Liang-Kuang; Mok, Greta S. P.; Hsu, Shih-Ming; Wu, Tung-Hsin

    2011-10-01

    Triple rule-out coronary CT angiography (TRO-CTA) is a new approach for providing noninvasive visualization of coronary arteries with simultaneous evaluation of pulmonary arteries, thoracic aorta and other intrathoracic structures. The increasing use of TRO-CTA examination with longer scan length is associated with the concerns about radiation dose and their corresponding cancer risk. The purpose of this study is to evaluate organ dose and effective dose for the TRO-CTA examination with 2 scan lengths: TRO std and TRO ext, using 256-slice CT. TRO-CTA examinations were performed on a 256-slice CT scanner without ECG-based tube current modulation. Absorbed organ doses were measured using an anthropomorphic phantom and thermal-luminance dosimeters (TLDs). Effective dose was determined by taking a sum of the measured absorbed organ doses multiplied with the tissue weighting factor based on ICRP-103, and compared to that calculated using the dose-length product (DLP) method. We obtained high organ doses in the thyroid, esophagus, breast, heart and lung in both TRO-CTA protocols. Effective doses of the TRO std and TRO ext protocols with the phantom method were 26.37 and 42.49 mSv, while those with the DLP method were 19.68 and 38.96 mSv, respectively. Our quantitative dose information establishes a relationship between radiation dose and scanning length, and can provide a practical guidance to best clinical practice.

  8. Sigmoid sinus diverticulum and pulsatile tinnitus - Analysis of CT scans from 15 cases

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhaohui; Wang, Zhenchang; Xian, Junfang; Wang, Yongzhe; Liang, Xihong [Dept. of Radiology, Capital Medical Univ., Beijing Tongren Hospital, Beijing (China); Chen, Chengfang; Gong, Shusheng; Ma, Xiaobo; Li, Yi [Dept. of Otolaryngology Head and Neck Surgery, Capital Medical Univ., Beijing Tongren Hospital, Beijing (China)], e-mail: gongs@ccmu.edu.cn

    2013-09-15

    Background: Although the imaging features of sigmoid sinus diverticulum induced pulsatile tinnitus (PT) have been presented in some extent, detailed imaging findings still have not been systematically evaluated and precise diagnostic radiographic criteria has not been established. Purpose: To examine the computed tomography (CT) characteristics of sigmoid sinus diverticulum accompanied with PT. Material and Methods: Fifteen PT patients with sigmoid sinus diverticula proven by surgery were recruited after consenting. CT images of 15 patients were obtained and analyzed, including features of diverticula, brain venous systems, integrity of the sigmoid plate, and the degree of temporal bone pneumatization. Results: Sigmoid sinus diverticulum was located on the same side of PT in 15 patients. Diverticula originated at the superior curve of the sigmoid sinus in 11 patients and the descending segment of the sigmoid sinus in four patients. Sigmoid sinus diverticula focally eroded into the adjacent mastoid air cells in 12 patients and mastoid cortex in three patients. Among eight patients with unilateral dominant brain venous systems, the diverticula were seen on the dominant side in seven patients and non-dominant side in one patient. In contrast, the other seven patients showed co-dominant brain venous systems, with three presenting diverticula on the right side and four on the left. More notably, dehiscent sigmoid plate on the PT side was demonstrated in all patients. In addition, temporal bone hyper-pneumatization was found in nine patients, good and moderate pneumatization in three patients, respectively. Conclusion: Dehiscent sigmoid plate and extensive temporal bone pneumatization are two important imaging characteristics of the PT induced by sigmoid sinus diverticulum.

  9. Multislice CT scans in patients on extracorporeal membrane oxygenation: Emphasis on hemodynamic changes and imaging pitfalls

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Kao Lang; Wang, Yu Feng; Chang, Yeun Chung; Huang, Shu Chien; Chen, Shyh Jye; Chang, Chin Chen [National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei (China); Tsang, Yuk Ming [Dept. of Medical Imaging, Far Eastern Memorial Hospital, New Taipei City (China)

    2014-06-15

    This pictorial review provides the principles of extracorporeal membrane oxygenation (ECMO) support and associated CT imaging features with emphasis on the hemodynamic changes and possible imaging pitfalls encountered. It is important that radiologists in ECMO centers apply well-designed imaging protocols and familiarize themselves with post-contrast CT imaging findings in patients on ECMO.

  10. Noise reduction and vascular enhancement in 4D CT perfusion scans

    NARCIS (Netherlands)

    Mendrik, A.M.

    2010-01-01

    Computed tomography (CT) uses X-ray radiation to construct images. Applying X-ray radiation to the human body may damage the tissue and increases the risk of inducing cancer. Therefore, the radiation dose should be kept as low as reasonably achievable (ALARA). This is especially true for 4D CT perfu

  11. CT scanning in two cases of lipoma of the spinal cord

    NARCIS (Netherlands)

    Dossetor, R.S.; Kaiser, M.; Veiga-Pires, J.A.

    1979-01-01

    Two cases of lipoma of the spinal cord are presented. CT gives a specific diagnosis in this condition without any contrast being given. It is important to make a preoperative diagnosis, as in lipoma of the spinal cord biopsy is dangerous and frequently makes the patient worse. CT is also valuable as

  12. Detailed analysis of the density change on chest CT of COPD using non-rigid registration of inspiration/expiration CT scans

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Young [Chonbuk National University Medical School and Hospital, Research Institute of Clinical Medicine, Department of Radiology, Jeollabuk-do (Korea, Republic of); University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Seo, Joon Beom; Lee, Hyun Joo; Kim, Namkug; Lee, Eunsol; Lee, Sang Min; Oh, Sang Young [University of Ulsan College of Medicine, Asan Medical Center, Department of Radiology and Research Institute of Radiology, Seoul (Korea, Republic of); Hwang, Hye Jeon [Hallym University Sacred Heart Hospital, Department of Radiology, Hallym University College of Medicine, Gyeonggi-do (Korea, Republic of); Oh, Yeon-Mok; Lee, Sang-Do [University of Ulsan College of Medicine, Asan Medical Center, Department of Pulmonary and Critical Care Medicine, and Clinical Research Center for Chronic Obstructive Airway Diseases, Seoul (Korea, Republic of)

    2014-09-14

    One objective was to evaluate the air trapping index (ATI), measured by inspiration/expiration CT, in COPD patients and nonsmokers. Another objective was to assess the association between the pulmonary function test (PFT) and CT parameters such as ATI or other indices, separately in the whole lung, in emphysema, and in hyperinflated and normal lung areas. One hundred and thirty-eight COPD patients and 29 nonsmokers were included in our study. The ATI, the emphysema index (EI), the gas trapping index (Exp -856) and expiration/inspiration ratio of mean lung density (E/Iratio of MLD) were measured on CT. The values of the whole lung, of emphysema, and of hyperinflated and normal lung areas were compared and then correlated with various PFT parameters. Compared with nonsmokers, COPD patients showed a higher ATI in the whole lung and in each lung lesion (all P < 0.05). The ATI showed a higher correlation than EI with FEF{sub 25-75%}, RV and RV/TLC, and was comparable to Exp -856 and the E/I ratio of MLD. The ATI of emphysema and hyperinflated areas on CT showed better correlation than the normal lung area with PFT parameters. Detailed analysis of density change at inspiration and expiration CT of COPD can provide new insights into pulmonary functional impairment in each lung area. (orig.)

  13. Evaluation of bismuth shielding effectiveness in reducing breast absorbed dose during thoracic CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, T. C.; Mourao, A. P.; Santana, P. C.; Silva, T. A. [Federal University of Minas Gerais, Program of Nuclear Science and Techniques, Av. Pte. Antonio Carlos 6627, 31270-901 Belo Horizonte, Minas Gerais (Brazil)

    2015-10-15

    Computed Tomography (CT) is an essential method for tracking neoplasia and efficiently diagnosing a wide variety of thoracic diseases. CT is generally considered the most accurate choice for lung examination. Due to the growing use of CT, breast and other superficial and radiosensitive organs are unnecessarily irradiated during radiological procedures, thus requiring the development of strategies appropriate to optimize and, if possible, to reduce the radiation dose. The use of bismuth shielding to reduce radiation dose absorbed by breast during thoracic CT examinations has been the subject of many studies recently published by Brazilian and foreign authors of various fields. The purpose of this paper is both to accurately determine the glandular dose when breast is exposed to radiation and to assess the reduction in absorbed dose during thoracic CT examinations, using a set of Thermoluminescent Dosimeters, an anthropomorphic phantom and bismuth shielding. (Author)

  14. Automated detection and volumetric segmentation of the spleen in CT scans; Automatische Detektion und volumetrische Segmentierung der Milz in CT-Untersuchungen

    Energy Technology Data Exchange (ETDEWEB)

    Hammon, M.; Dankerl, P.; Janka, R.; Uder, M.; Cavallaro, A. [Universitaetsklinikum Erlangen (Germany). Radiologisches Inst.; Kramer, M.; Seifert, S.; Tsymbal, A.; Costa, M.J. [Siemens AG, Erlangen (Germany). Corporate Technology

    2012-08-15

    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{sup 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{sup 3} compared to 281.58 {+-} 130.21 cm{sup 3} in mV and 268.93 {+-} 104.60 cm{sup 3} in eV. The correlation coefficient was 0.99 (coefficient of determination (R{sup 2}) = 0.98) for aV and mV, 0.91 (R{sup 2} = 0.83) for mV and eV and 0.91 (R{sup 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{sup 2} = 0.84), mV and eV (0.95; R{sup 2} = 0.91) and aV and eV (0.83; R{sup 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.)

  15. CT-scan prediction of thyroid cartilage invasion for early laryngeal squamous cell carcinoma.

    Science.gov (United States)

    Hartl, Dana M; Landry, Guillaume; Bidault, François; Hans, Stéphane; Julieron, Morbize; Mamelle, Gérard; Janot, François; Brasnu, Daniel F

    2013-01-01

    Treatment choice for laryngeal cancer may be influenced by the diagnosis of thyroid cartilage invasion on preoperative computed tomography (CT). Our objective was to determine the predictive value of CT for thyroid cartilage invasion in early- to mid-stage laryngeal cancer. Retrospective study (1992-2008) of laryngeal squamous cell carcinoma treated with open partial laryngectomy and resection of at least part of the thyroid cartilage. Previous laser surgery, radiation therapy, chemotherapy and second primaries were excluded. CT prediction of thyroid cartilage invasion was determined by specialized radiologists. Tumor characteristics and pathologic thyroid cartilage invasion were compared to the radiologic assessment. 236 patients were treated by vertical (20 %), supracricoid (67 %) or supraglottic partial laryngectomy (13 %) for tumors staged cT1 (26 %), cT2 (55 %), and cT3 (19 %). The thyroid cartilage was invaded on pathology in 19 cases (8 %). CT's sensitivity was 10.5 %, specificity 94 %, positive predictive value 13 %, and negative predictive value 92 %. CT correctly predicted thyroid cartilage invasion in only two cases for an overall accuracy of 87 %. Among the false-positive CT's, tumors involving the anterior commissure were significantly over-represented (61.5 % vs. 27 %, p = .004). Tumors with decreased vocal fold (VF) mobility were significantly over-represented in the group of false-negatives (41 vs. 13 %, p = .0035). Preoperative CT was not effective in predicting thyroid cartilage invasion in these early- to mid-stage lesions, overestimating cartilage invasion for AC lesions and underestimating invasion for lesions with decreased VF mobility.

  16. Comparison between FDG Uptake and Clinicopathologic and Immunohistochemical Parameters in Pre-operative PET/CT Scan of Primary Gastric Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Han, Eun Ji; Choi, Woo Hee; Chung, Yong An; Kim, Ki Jun; Maeng, Lee So; Sohn, Kyung Myung; Jung, Hyun Suk; Sohn, Hyung Sun; Chung, Soo Kyo [College of Medicine, The Catholic University of Korea, Seoul (Korea, Republic of)

    2009-02-15

    The purpose of this study was to find out what clinicopathologic or immunohistochemical parameter that may affect FDG uptake of primary tumor in PET/CT scan of the gastric carcinoma patient. Eighty-nine patients with stomach cancer who underwent pre-operative FDG PET/CT scans were included. In cases with perceptible FDG uptake in primary tumor, the maximum standardized uptake value (SUVmax) was calculated. The clinicopathologic results such as depth of invasion (T stage), tumor size, lymph node metastasis, tumor differentiation and Lauren's classification and immunohistochemical markers such as Ki-67 index, expression of p53, EGFR, Cathepsin D, c-erb-B2 and COX-2 were reviewed. Nineteen out of 89 gastric carcinomas showed imperceptible FDG uptake on PET/CT images. In cases with perceptible FDG uptake in primary tumor, SUVmax was significantly higher in T2, T3 and T4 tumors than T1 tumors (5.8{+-}3.1 vs. 3.7{+-}2.1, p=0.002). SUVmax of large tumors (above or equal to 3 cm) was also significantly higher than SUVmax of small ones (less than 3 cm) (5.7{+-}3.2 vs. 3.7{+-}2.0, p=0.002). The intestinal types of gastric carcinomas according to Lauren showed higher FDG uptake compared to the non-intestinal types (5.4{+-}2.8 vs. 3.7{+-}1.3, p=0.003). SUVmax between p53 positive group and negative group was significantly different (6.0{+-}2.8 vs. 4.4{+-}3.0, p=0.035). No significant difference was found in presence of LN metastasis, tumor differentiation, Ki-67 index, and expression of EGFR, Cathepsin D, c-erb-B2 and COX-2. T stage of gastric carcinoma influenced the detectability of gastric cancer on FDG PET/CT scan. When gastric carcinoma was perceptible on PET/CT scan, T stage, size of primary tumor, Lauren's classification and p53 expression were related to degree of FDG uptake in primary tumor.

  17. An optimal set of landmarks for metopic craniosynostosis diagnosis from shape analysis of pediatric CT scans of the head

    Science.gov (United States)

    Mendoza, Carlos S.; Safdar, Nabile; Myers, Emmarie; Kittisarapong, Tanakorn; Rogers, Gary F.; Linguraru, Marius George

    2013-02-01

    Craniosynostosis (premature fusion of skull sutures) is a severe condition present in one of every 2000 newborns. Metopic craniosynostosis, accounting for 20-27% of cases, is diagnosed qualitatively in terms of skull shape abnormality, a subjective call of the surgeon. In this paper we introduce a new quantitative diagnostic feature for metopic craniosynostosis derived optimally from shape analysis of CT scans of the skull. We built a robust shape analysis pipeline that is capable of obtaining local shape differences in comparison to normal anatomy. Spatial normalization using 7-degree-of-freedom registration of the base of the skull is followed by a novel bone labeling strategy based on graph-cuts according to labeling priors. The statistical shape model built from 94 normal subjects allows matching a patient's anatomy to its most similar normal subject. Subsequently, the computation of local malformations from a normal subject allows characterization of the points of maximum malformation on each of the frontal bones adjacent to the metopic suture, and on the suture itself. Our results show that the malformations at these locations vary significantly (p<0.001) between abnormal/normal subjects and that an accurate diagnosis can be achieved using linear regression from these automatic measurements with an area under the curve for the receiver operating characteristic of 0.97.

  18. ELEVATED SERUM S-100B LEVELS WITH NEGATIVE PET/TC AND CT-SCAN IN A METASTATIC MELANOMA PATIENT.

    Directory of Open Access Journals (Sweden)

    Francesco Spagnolo

    2012-01-01

    Full Text Available The incidence of melanoma is increasing worldwide. Prognosis for metastatic melanoma is poor; early detection of recurrent or metastatic disease may improve therapy strategies and survival. Several possible biomarkers for melanoma have been investigated. S-100B was found to be a sensitive and specific serological tumor marker; furthermore, its concentrations are correlated with the clinical stage of disease. Serum S-100B is also an independent prognostic factor for survival and can be used to monitor response to treatment. We present the case of a 55 year old woman, whose diagnosis of melanoma distant metastases was suggested by a progressive increase in serum S-100B levels, while other blood tests, physical exam and imaging techniques, including PET/TC and CT-scan, were negative. S-100B is currently the most accurate biomarker in melanoma patients; its role in the management of melanoma patients has been the object of study and it has been documented as a valuable independent prognostic factor. The case we present shows that S-100B levels may also be useful in the early detection of melanoma recurrences, even when imaging techniques are negative.

  19. {sup 11}C-Choline PET/CT in patients with hormone-resistant prostate cancer showing biochemical relapse after radical prostatectomy

    Energy Technology Data Exchange (ETDEWEB)

    Ceci, Francesco; Ambrosini, Valentina; Boschi, Stefano; Fanti, Stefano [University of Bologna, Nuclear Medicine Unit, Department of Haematology Oncology and Laboratory Medicine, Azienda Ospedaliero-Universitaria di Bologna, Policlinico Sant' Orsola-Malpighi, Bologna (Italy); Castellucci, Paolo [University of Bologna, Nuclear Medicine Unit, Department of Haematology Oncology and Laboratory Medicine, Azienda Ospedaliero-Universitaria di Bologna, Policlinico Sant' Orsola-Malpighi, Bologna (Italy); Azienda Ospedaliero-Unversitaria di Bologna Policlinico Sant' Orsola-Malpighi, UO di Medicina Nucleare, PAD. 30, Bologna (Italy); Mamede, Marcelo [Universidade Federal de Minas Gerais, Molecular Imaging Center, Belo Horizonte (Brazil); Schiavina, Riccardo; Martorana, Giuseppe [University of Bologna, Department of Urology, Azienda Ospedaliero-Universitaria di Bologna, Policlinico Sant' Orsola-Malpighi, Bologna (Italy); Rubello, Domenico [' Santa Maria della Misericordia' Hospital, Department of Nuclear Medicine and PET/CT Centre, Rovigo (Italy); Fuccio, Chiara [Fondazione Salvatore Maugeri, Service of Nuclear Medicine, Pavia (Italy)

    2013-02-15

    To determine the diagnostic efficacy of {sup 11}C-choline PET/CT in patients with prostate cancer (PC) after radical prostatectomy who presented with increasing PSA levels during follow-up in spite of being on hormone treatment (HT), and therefore showing HT resistance. We evaluated a large series of 157 consecutive PC patients previously treated by radical prostatectomy who presented with biochemical recurrence with increasing PSA levels in spite of ongoing HT (HT-resistant patients). At the time of {sup 11}C-choline PET/CT, the mean value of trigger PSA level was 8.3 (range 0.2 - 60.6 ng/mL), the mean PSA doubling time (PSAdt) was 5.3 (range 0.4 - 35 months), and the mean PSA velocity (PSAvel) was 22.1 ng/mL/year (range 0.12 - 82 ng/mL/year). {sup 11}C-Choline PET/CT was performed following a standard procedure at our centre to investigate increasing PSA levels, either as the first imaging procedure or in patients with negative conventional imaging. At the time of {sup 11}C-choline PET/CT all patients were receiving HT (61 were receiving monotherapy and 96 multidrug therapy). PET-positive findings were validated by: (a) transrectal US-guided biopsy in patients with recurrence in the prostatic bed, (b) surgical pelvic lymphadenectomy, (c) other imaging modalities, including repeated {sup 11}C-choline PET/CT, performed during a minimum follow-up of 12-months. {sup 11}C-Choline PET/CT showed positive findings in 104 of the 157 patients (66 %). {sup 11}C-choline PET/CT detected: a single lesion in 40 patients (7 in the prostate bed, 10 in lymph nodes, 22 in bone, 1 at another site); two lesions in 18 patients (7 in lymph nodes, 7 in bone, 4 in both lymph nodes and bone); three or four lesions in 7 patients (4 in lymph nodes, 2 in bone, 1 at another site); and more than four lesions in the remaining 39 patients (2 in the prostate bed, 12 in lymph nodes, 12 in bone, 11 in both lymph nodes and bone, 2 at other sites). In {sup 11}C-choline PET-negative patients, the mean

  20. The potential of positron emission tomography/computerized tomography (PET/CT) scanning as a detector of high-risk patients with oral infection during preoperative staging.

    Science.gov (United States)

    Yamashiro, Keisuke; Nakano, Makoto; Sawaki, Koichi; Okazaki, Fumihiko; Hirata, Yasuhisa; Takashiba, Shogo

    2016-08-01

    It is sometimes difficult to determine during the preoperative period whether patients have oral infections; these patients need treatment to prevent oral infection-related complications from arising during medical therapies, such as cancer therapy and surgery. One of the reasons for this difficulty is that basic medical tests do not identify oral infections, including periodontitis and periapical periodontitis. In this report, we investigated the potential of positron emission tomography/computerized tomography (PET/CT) as a diagnostic tool in these patients. We evaluated eight patients during the preoperative period. All patients underwent PET/CT scanning and were identified as having the signs of oral infection, as evidenced by (18)F-fludeoxyglucose (FDG) localization in the oral regions. Periodontal examination and orthopantomogram evaluation showed severe infection or bone resorption in the oral regions. (18)F-FDG was localized in oral lesions, such as severe periodontitis, apical periodontitis, and pericoronitis of the third molar. The densities of (18)F-FDG were proportional to the degree of inflammation. PET/CT is a potential diagnostic tool for oral infections. It may be particularly useful in patients during preoperative staging, as they frequently undergo scanning at this time, and those identified as having oral infections at this time require treatment before cancer therapy or surgery. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Semiautomated three-dimensional segmentation software to quantify carpal bone volume changes on wrist CT scans for arthritis assessment.

    Science.gov (United States)

    Duryea, J; Magalnick, M; Alli, S; Yao, L; Wilson, M; Goldbach-Mansky, R

    2008-06-01

    Rapid progression of joint destruction is an indication of poor prognosis in patients with rheumatoid arthritis. Computed tomography (CT) has the potential to serve as a gold standard for joint imaging since it provides high resolution three-dimensional (3D) images of bone structure. The authors have developed a method to quantify erosion volume changes on wrist CT scans. In this article they present a description and validation of the methodology using multiple scans of a hand phantom and five human subjects. An anthropomorphic hand phantom was imaged with a clinical CT scanner at three different orientations separated by a 30-deg angle. A reader used the semiautomated software tool to segment the individual carpal bones of each CT scan. Reproducibility was measured as the root-mean-square standard deviation (RMMSD) and coefficient of variation (CoV) between multiple measurements of the carpal volumes. Longitudinal erosion progression was studied by inserting simulated erosions in a paired second scan. The change in simulated erosion size was calculated by performing 3D image registration and measuring the volume difference between scans in a region adjacent to the simulated erosion. The RMSSD for the total carpal volumes was 21.0 mm3 (CoV = 1.3%) for the phantom, and 44.1 mm3 (CoV = 3.0%) for the in vivo subjects. Using 3D registration and local volume difference calculations, the RMMSD was 1.0-3.0 mm3 The reader time was approximately 5 min per carpal bone. There was excellent agreement between the measured and simulated erosion volumes. The effect of a poorly measured volume for a single erosion is mitigated by the large number of subjects that would comprise a clinical study and that there will be many erosions measured per patient. CT promises to be a quantifiable tool to measure erosion volumes and may serve as a gold standard that can be used in the validation of other modalities such as magnetic resonance imaging.

  2. Integration of 3D anatomical data obtained by CT imaging and 3D optical scanning for computer aided implant surgery

    Directory of Open Access Journals (Sweden)

    Paoli Alessandro

    2011-02-01

    Full Text Available Abstract Background A precise placement of dental implants is a crucial step to optimize both prosthetic aspects and functional constraints. In this context, the use of virtual guiding systems has been recognized as a fundamental tool to control the ideal implant position. In particular, complex periodontal surgeries can be performed using preoperative planning based on CT data. The critical point of the procedure relies on the lack of accuracy in transferring CT planning information to surgical field through custom-made stereo-lithographic surgical guides. Methods In this work, a novel methodology is proposed for monitoring loss of accuracy in transferring CT dental information into periodontal surgical field. The methodology is based on integrating 3D data of anatomical (impression and cast and preoperative (radiographic template models, obtained by both CT and optical scanning processes. Results A clinical case, relative to a fully edentulous jaw patient, has been used as test case to assess the accuracy of the various steps concurring in manufacturing surgical guides. In particular, a surgical guide has been designed to place implants in the bone structure of the patient. The analysis of the results has allowed the clinician to monitor all the errors, which have been occurring step by step manufacturing the physical templates. Conclusions The use of an optical scanner, which has a higher resolution and accuracy than CT scanning, has demonstrated to be a valid support to control the precision of the various physical models adopted and to point out possible error sources. A case study regarding a fully edentulous patient has confirmed the feasibility of the proposed methodology.

  3. Evaluation of mediastinal lymph nodes using 18 F-FDG PET-CT scan and its histopathologic correlation

    Directory of Open Access Journals (Sweden)

    Kumar Arvind

    2011-01-01

    Full Text Available Aims and Objectives: To determine the efficacy of integrated 18 F-fluorodeoxy glucose positron emission tomography-computed tomography ( 18 F-FDG PET-CT in the evaluation and characterization of mediastinal lymph nodes into benign and malignant pathology. Methods: Thirty-five patients with mediastinal lymphadenopathies without primary neoplastic or infective lung pathologies were included in the study. The lymph nodes were detected on contrast-enhanced CT scan of the chest. All patients underwent 18 F-FDG PET-CT scan for evaluation of mediastinal lymph nodes. Results of PET-CT were compared with histopathology of the lymph nodes and sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated. Statistical Analysis: The data were collected prospectively and analyzed using (SPSS Inc., Chicago, IL 11.5 software. Results: Histopathology results in 35 patients revealed tuberculosis in 12, sarcoidosis in 8, and lymphoma in 15. Maximum standardized uptake value (SUVmax of the benign lymph nodes ranged from 2.3 to 11.8 with a mean±standard deviation (SD of 5.02±3.26. SUVmax of the malignant lymph nodes ranged from 2.4 to 34 with a mean±SD of 10.8±8.12. There was a statistically significant difference between benign and malignant pathology (P<0.0059. 18 F-FDG PET-CT has sensitivity of 93% and specificity of 40% with SUVmax 2.5 as the cutoff. We found the optimal SUVmax cutoff to be 6.2 as determined by the receiver-operator characteristic curve. With 6.2 as cutoff, the sensitivity, specificity, and accuracy were 87%, 70%, and 77%, respectively. Conclusion : In countries where tuberculosis and other granulomatous diseases are endemic, SUVmax cutoff value of 2.5 has low specificity. Increasing the cutoff value can improve the specificity, while maintaining an acceptable sensitivity.

  4. Model-based x-ray energy spectrum estimation algorithm from CT scanning data with spectrum filter

    Science.gov (United States)

    Li, Lei; Wang, Lin-Yuan; Yan, Bin

    2016-10-01

    With the development of technology, the traditional X-ray CT can't meet the modern medical and industry needs for component distinguish and identification. This is due to the inconsistency of X-ray imaging system and reconstruction algorithm. In the current CT systems, X-ray spectrum produced by X-ray source is continuous in energy range determined by tube voltage and energy filter, and the attenuation coefficient of object is varied with the X-ray energy. So the distribution of X-ray energy spectrum plays an important role for beam-hardening correction, dual energy CT image reconstruction or dose calculation. However, due to high ill-condition and ill-posed feature of system equations of transmission measurement data, statistical fluctuations of X ray quantum and noise pollution, it is very hard to get stable and accurate spectrum estimation using existing methods. In this paper, a model-based X-ray energy spectrum estimation method from CT scanning data with energy spectrum filter is proposed. First, transmission measurement data were accurately acquired by CT scan and measurement using phantoms with different energy spectrum filter. Second, a physical meaningful X-ray tube spectrum model was established with weighted gaussian functions and priori information such as continuity of bremsstrahlung and specificity of characteristic emission and estimation information of average attenuation coefficient. The parameter in model was optimized to get the best estimation result for filtered spectrum. Finally, the original energy spectrum was reconstructed from filtered spectrum estimation with filter priori information. Experimental results demonstrate that the stability and accuracy of X ray energy spectrum estimation using the proposed method are improved significantly.

  5. Radiation dose reduction at a price: the effectiveness of a male gonadal shield during helical CT scans

    Directory of Open Access Journals (Sweden)

    Erdi Yusuf E

    2007-03-01

    Full Text Available Abstract Background It is estimated that 60 million computed tomography (CT scans were performed during 2006, with approximately 11% of those performed on children age 0–15 years. Various types of gonadal shielding have been evaluated for reducing exposure to the gonads. The purpose of this study was to quantify the radiation dose reduction to the gonads and its effect on image quality when a wrap-around male pediatric gonad shield was used during CT scanning. This information is obtained to assist the attending radiologist in the decision to utilize such male gonadal shields in pediatric imaging practice. Methods The dose reduction to the gonads was measured for both direct radiation and for indirect scattered radiation from the abdomen. A 6 cm3 ion chamber (Model 10X5-6, Radcal Corporation, Monrovia, CA was placed on a Humanoid real bone pelvic phantom at a position of the male gonads. When exposure measurements with shielding were made, a 1 mm lead wrap-around gonadal shield was placed around the ion chamber sensitive volume. Results The use of the shields reduced scatter dose to the gonads by a factor of about 2 with no appreciable loss of image quality. The shields reduced the direct beam dose by a factor of about 35 at the expense of extremely poor CT image quality due to severe streak artifacts. Conclusion Images in the direct exposure case are not useful due to these severe artifacts and the difficulties in positioning these shields on patients in the scatter exposure case may not be warranted by the small absolute reduction in scatter dose unless it is expected that the patient will be subjected to numerous future CT scans.

  6. Evaluation of Distal Femoral Rotational Alignment with Spiral CT Scan before Total Knee Arthroplasty (A Study in Iranian Population

    Directory of Open Access Journals (Sweden)

    Mahmoud Jabalameli

    2016-04-01

    Full Text Available Background: Evaluating the landmarks for rotation of the distal femur is a challenge for orthopedic surgeons. Although the posterior femoral condyle axis is a good landmark for surgeons, the surgical transepicondylar axis may be a better option with the help of preoperative CT scanning. The purpose of this study was to ascertain relationships among the axes’ guiding distal femur rotational alignment in preoperative CT scans of Iranian patients who were candidates for total knee arthroplasty and the effects of age, gender, and knee alignment on these relationships. Methods: One hundred and eight cases who were admitted to two university hospitals for total knee arthroplasty were included in this study. The rotation of the distal femur was evaluated using single axial CT images through the femoral epicondyle. Four lines were drawn digitally in this view: anatomical and surgical transepicondylar axes, posterior condylar axis and the Whiteside anteroposterior line. The alignment of the extremity was evaluated in the standing alignment view. Then the angles were measured along these lines and their relationship was evaluated. Results: The mean angle between the anatomical transepicondylar axis and posterior condylar axis and between the surgical transepicondylar axis and posterior condylar axis were 5.9 ± 1.6 degrees and 1.6±1.7 degrees respectively. The mean angle between the Whiteside’s anteroposterior line and the line perpendicular to the posterior condylar axis was 3.7±2.1 degrees. Significant differences existed between the two genders in these relationships. No significant correlation between the age of patients and angles of the distal femur was detected. The anatomical surgical transepicondylar axis was in 4.3 degrees external rotation in relation to the surgical transepicondylar axis. Conclusion: Preoperative CT scanning can help accurately determine rotational landmarks of the distal femur. If one of the reference axes cannot be

  7. Breast dose reduction for chest CT by modifying the scanning parameters based on the pre-scan size-specific dose estimate (SSDE)

    Energy Technology Data Exchange (ETDEWEB)

    Kidoh, Masafumi; Utsunomiya, Daisuke; Oda, Seitaro; Nakaura, Takeshi; Yuki, Hideaki; Hirata, Kenichiro; Namimoto, Tomohiro; Sakabe, Daisuke; Hatemura, Masahiro; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Faculty of Life Sciences, Honjo, Kumamoto (Japan); Funama, Yoshinori [Kumamoto University, Department of Medical Physics, Faculty of Life Sciences, Honjo, Kumamoto (Japan)

    2017-06-15

    To investigate the usefulness of modifying scanning parameters based on the size-specific dose estimate (SSDE) for a breast-dose reduction for chest CT. We scanned 26 women with a fixed volume CT dose index (CTDI{sub vol}) (15 mGy) and another 26 with a fixed SSDE (15 mGy) protocol (protocol 1 and 2, respectively). In protocol 2, tube current was calculated based on the patient habitus obtained on scout images. We compared the mean breast dose and the inter-patient breast dose variability and performed linear regression analysis of the breast dose and the body mass index (BMI) of the two protocols. The mean breast dose was about 35 % lower under protocol 2 than protocol 1 (10.9 mGy vs. 16.8 mGy, p < 0.01). The inter-patient breast dose variability was significantly lower under protocol 2 than 1 (1.2 mGy vs. 2.5 mGy, p < 0.01). We observed a moderate negative correlation between the breast dose and the BMI under protocol 1 (r = 0.43, p < 0.01); there was no significant correlation (r = 0.06, p = 0.35) under protocol 2. The SSDE-based protocol achieved a reduction in breast dose and in inter-patient breast dose variability. (orig.)

  8. Nuclear magnetic resonance imaging with cardiac synchronization in chronic thrombosis of main pulmonary arteries. A case review with CT scan imaging correlation

    Energy Technology Data Exchange (ETDEWEB)

    Coulomb, M.; Wolf, J.E.; Rose-Pittet, L.; Le Bas, J.F.; Dalsoglio, S.; Paramelle, B.

    Results of nuclear magnetic resonance exploration in a patient with chronic thrombosis of main pulmonary arteries are used to outline an elementary semiology in agreement with current documented data. Signs observed relate to the thrombosis and showing of flow due to associated pulmonary artery hypertension. Cardiac synchronization is essential: obtaining 2 echos by the spin-echo technique allows differentiation of circulatory slowing phenomena, which provoke increased strength of 2nd echo, from the thrombus itself. Correlations established with V/Q scintigraphy, angiography and CT scan findings in this case provided preliminary evaluation of use of this imaging technique in this affection.

  9. A computerized scheme for localization of vertebral bodies on body CT scans

    Science.gov (United States)

    Hayashi, Tatsuro; Chen, Huayue; Miyamoto, Kei; Zhou, Xiangrong; Hara, Takeshi; Yokoyama, Ryujiro; Kanematsu, Masayuki; Hoshi, Hiroaki; Fujita, Hiroshi

    2011-03-01

    The multidetector row computed tomography (MDCT) method has the potential to be used for quantitative analysis of osteoporosis with higher accuracy and precision than that provided by conventional two-dimensional methods. It is desirable to develop a computer-assisted scheme for analyzing vertebral geometry using body CT images. The aim of this study was to design a computerized scheme for the localization of vertebral bodies on body CT images. Our new scheme involves the following steps: (i) Re-formation of CT images on the basis of the center line of the spinal canal to visually remove the spinal curvature, (ii) use of information on the position of the ribs relative to the vertebral bodies, (iii) the construction of a simple model on the basis of the contour of the vertebral bodies on CT sections, and (iv) the localization of individual vertebral bodies by using a template matching technique. The proposed scheme was applied to 104 CT cases, and its performance was assessed using the Hausdorff distance. The average Hausdorff distance of T2-L5 was 4.3 mm when learning models with 100 samples were used. On the other hand, the average Hausdorff distance with 10 samples was 5.1 mm. The results of our assessments confirmed that the proposed scheme could provide the location of individual vertebral bodies. Therefore, the proposed scheme may be useful in designing a computer-based application that analyzes vertebral geometry on body CT images.

  10. The skin-to-calyx distance measured by renal ct scan and ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Shan, Chen Jen; Mazzucchi, Eduardo; Payão, Fabio; Gomes, Andrea Cavalanti; Baroni, Ronaldo Hueb; Torricelli, Fabio Cesar; Vicentini, Fabio Carvalho; Srougi, Miguel [Hospital das Clínicas, University of Sao Paulo Medical School, Sao Paulo, SP (Brazil)

    2014-03-15

    Purpose: We developed a stereotactic device to guide the puncture for percutaneous nephrolithotripsy, which uses the distance from the target calyx to its perpendicular point on skin (SCD) to calculate the needle´s entry angle. This study seeks to validate the use of measurements obtained by ultrasound (US) and computerized tomography (CT) for needle´s entry angle calculation and to study factors that may interfere in this procedure. Materials and Methods: Height, weight, abdominal circumference, CT of the urinary tract in dorsal decubitus (DD) and ventral decubitus (VD), and US of the kidneys in VD were obtained from thirty-five renal calculi patients. SCD obtained were compared and correlated with body-mass index (BMI). Results: BMI was 28.66 ± 4.6 Kg/m2. SCD on CT in DD was 8.40 ± 2.06cm, in VD was 8.32 ± 1.95cm, in US was 6.74 ± 1.68cm. SCD measured by US and CT were statistically different (p < 0.001), whereas between CT in DD and VD were not. SCD of the lower calyx presented moderate correlation with BMI. Conclusion: SCD obtained by CT in ventral and dorsal decubitus may be used for calculation of the needle´s entry angle. SCD obtained by US cannot be used. A rule for the correlation between BMI and the SCD could not be determined. (author)

  11. Optimal scan time of dual-phase spiral CT in normal rabbit liver : effect of contrast injection rate

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Byung Kook; Kim, Sang Ho; Liu, Wei Chiang [Sungae General Hospital, Seoul (Korea, Republic of)] (and others)

    1999-06-01

    To determine the effect of contrast injection rate on rabbit liver enhancement and the optimal temporal window for dual-phase spiral CT of rabbit liver at each injection rate Using spiral CT, seven New Zealand White rabbits underwent dynamic scanning at one level of liver. Three protocols of contrast injection rates were employed, namely 0.3ml/sec(group 1), 1 ml/sec(group 2) and 2 ml/sec(group 3). During 120 seconds of total scan time, the scan interval was 3 seconds. Densities of the aorta, liver and portal vein were averaged in equivalent time. The different injection rate protocols were compared for peak enhancement/time on a time density curve. Mean peak enhancement (HU) in equivalent time(secs) was 310/18(group 1), 383/9(group 2) and 357/6(group 3) in the aorta ; 34/36, 40/36 and 41/30 in the liver ; and 135/36, 153/24 and 170/21 in the portal vein. The temporal window during the arterial phase was 12-21 sec(group 1), 6-12 sec(group 2), and 6-12 sec(group 3). The temporal window during the portal phase was from 30 sec(0.3ml/sec), 21 sec(1ml/sec) and 21sec(2ml/sec). During dual-phase spiral CT, the temporal window for liver scanning should be determined according to each contrast injection rate. A slow contrast injection rate prolongs the temporal window during the arterial phase.

  12. Detection of small hepatocellular carcinoma: Comparison of dynamic enhancement magnetic resonance imaging and multiphase multirow-detector helical CT scanning

    Institute of Scientific and Technical Information of China (English)

    Hong Zhao; Jin-Lin Yao; Ying Wang; Kang-Rong Zhou

    2007-01-01

    AIM: To compare the gadolinium-enhanced multiphase dynamic magnetic resonance imaging (MRI) and multiphase multirow-detector helical CT (MDCT)scanning for detection of small hepatocellular carcinoma (HCC).METHODS: MDCT scanning and baseline MRI with SE T1-WI and T2-WI sequence combined with FMPSPGR sequence were performed in 37 patients with 43 small HCCs. Receiver operating characteristic (ROC) curves were plotted to analyze the results for modality.RESULTS: The areas below ROC curve (Az) were calculated. There was no statistical difference in dynamic enhancement MDCT and MRI. The detection rate of small HCC was 97.5%-97.6% on multiphase MDCT scanning and 90.7%-94.7% on MRI, respectively. The sensitivity of detection for small HCC on MDCT scanning was higher than that on dynamic enhancement MRI. The sensitivity of detection for minute HCC (tumor diameter ≤ 1 cm)was 90.0%-95.0% on MDCT scanning and 70.0%-85.0% on MRI, respectively.CONCLUSION: MDCT scanning should be performed for early detection and effective treatment of small HCC in patients with chronic hepatitis and cirrhosis during follow-up.

  13. {sup 99m}Tc-HDP Pinhole Bone Scan Features of Undetached Osteochondritis Dissecans of the Femoral Condyle: Report of a Case with Radiography, CT, and MRI Correlation

    Energy Technology Data Exchange (ETDEWEB)

    Bahk, Yong Whee [Sung Ae Hospital, Seoul (Korea, Republic of); Choi, Woo Hee [Seoul St. Mary' s Hospital, Catholic University Medical School, Seoul (Korea, Republic of)

    2009-02-15

    OCD may be initiated by arrest of bone growth and subchondral osteosclerosis followed by either cartilage hypertrophy with calcification or enfolding with osteochondral bridging. Diagnosis can be made in most instances using magnetic resonance imaging (MRI) or computed tomography (CT) or invasive arthroscopy. As to usefulness of conventional radiography (CR) opinions diverge as some held it to be of limited value while others valuable. The controversy seems to be due to semantic confusion of OCD from osteonecrosis (ON) which are different entities. This report will describe a case of undetached OCD occurred in the medial femoral condyle in a middle-aged female. It was free of symptom and incidentally discovered on {sup 99m}Tc-HDP pinhole scan performed for patellar injury. Pinhole scan findings of OCD are correlated to those of CR, CT, and MRI. An electronic search of literature failed to reveal earlier publication of bone scan features of undetached OCD. Pathologically, OCD differs from ON in that the fragment in the former condition comes off from a normal vascular bony bed while that in the latter separates from an avascular bony bed. Indeed, bone fragment in ON is devascularized but that in OCD maintains vascularity until weighted images, respectively and the halo showed low signal intensity on both T1 and T2 images.

  14. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... CT Scanning of the Abdomen and Pelvis? What is CT Scanning of the Abdomen/Pelvis? Computed tomography, ... the body being studied. top of page How is the CT scan performed? The technologist begins by ...