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Sample records for helical ct diagnosis

  1. Dual phase helical CT: diagnosis value for early pancreatic carcinoma

    International Nuclear Information System (INIS)

    Shen Bingqi; Zhang Ling; Zheng Keguo; Xu Dasheng

    2006-01-01

    Objective: To study dual-phase helical CT for the evaluation of early pancreatic cacinoma. Methods: Dual-phase helical CT was performed on 21 patients with early pancreatic carcinoma. In the enhanced imaging the contrast material was intravenously injected in a dose of 1.5 ml/kg at a rate of 3 ml/s. The image acquisition of the lesion in pancreatic phase (PP) and portal venous phase (PVP) were started at 35 seconds and 65 seconds after the start of the injection respectively. The enhancement of normal pancreas and tumor during the two phases was observed and compared. All data were statistically analyzed. Results: Tumor-pancreas contrast was significantly greater in PP (45.16±113.23) HU than in PVP (23.15±12.44) HU (t=2.13, P<0.01). Conclusion: Dual-phase helical CT scan for pancreas, including the imaging of the pancreatic and portal , venous phase, can be applied as an optimal selection. It can delineate early pancreatic carcinoma clearly and provide more information for the diagnosis of the lesion. The tumor-pancreas contrast was much higher' in PP than in PVP. (authors)

  2. Multislice helical CT in the diagnosis of hilar cholangiocarcinoma

    International Nuclear Information System (INIS)

    Yang Li; Zhao Shaohong; Nie Yongkang; Zhao Hong; Fang Jie; Cai Zulong; Yang Zhou; Ying Yifeng

    2005-01-01

    Objective: To investigate the value ofMSCT in observing the direct findings of hilar cholangiocarcinoma1Methods Multislice helical CT studies were performed on the upper abdomen in 19 consecutive patientswith painless jaundice1 Precontrast and dynamic contrast enhanced (25 s phase and 60 s phase) scanswere conducted, and 3D imageswere reconstructed using enhanced raw data in 15 cases1 The direct CT findings of hilar cholangiocarcinoma were studied by three radiologists respectively in a 32scale strategy1 The morphological features and extension of bile duct involvement by hilar cholangiocarcinoma were analyzed1 All the 19 caseswere pathologically p roved as hilar cholangiocarcinoma by surgery (15 cases) and ERCP ( 4 cases) 1 Results The direct findings and extension of hilar cholangiocarcinoma could be demonstrated in 14 out of 15 3D reconstruction images, 8 out of 19 in 25 s phase, and 7 out of 19 in 60 s phase of contrast enhancement scans, respectively ( P < 0105 ) 1 The tumor involving the bile duct was enhanced most remarkablely on 25 s phase, and the bile duct wall thickening, bile duct narrowing or occlusion were demonstrated as the p rimary findings of hilar cholangiocarcinoma1 The intraductal sp read of tumor could be demonstrated as small nodules on the bile duct wall p roximal or distal to the tumor1 Conclusion. The tumor involving the bile duct can be enhanced most remarkablely on 25 s phase after contrast injection1 Multislice helical CT, especially 3D reconstructed images, can be used to detect the direct findings of hilar cholangiocarcinomas and the extension of tumor involving the bile duct. (authors)

  3. Computer-aided diagnosis workstation and database system for chest diagnosis based on multi-helical CT images

    Science.gov (United States)

    Satoh, Hitoshi; Niki, Noboru; Mori, Kiyoshi; Eguchi, Kenji; Kaneko, Masahiro; Kakinuma, Ryutarou; Moriyama, Noriyuki; Ohmatsu, Hironobu; Masuda, Hideo; Machida, Suguru; Sasagawa, Michizou

    2006-03-01

    Multi-helical CT scanner advanced remarkably at the speed at which the chest CT images were acquired for mass screening. Mass screening based on multi-helical CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. To overcome this problem, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images and a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification. We also have developed electronic medical recording system and prototype internet system for the community health in two or more regions by using the Virtual Private Network router and Biometric fingerprint authentication system and Biometric face authentication system for safety of medical information. Based on these diagnostic assistance methods, we have now developed a new computer-aided workstation and database that can display suspected lesions three-dimensionally in a short time. This paper describes basic studies that have been conducted to evaluate this new system. The results of this study indicate that our computer-aided diagnosis workstation and network system can increase diagnostic speed, diagnostic accuracy and safety of medical information.

  4. Utility of three-dimensional helical CT in the diagnosis of breast cancer

    International Nuclear Information System (INIS)

    Maeda, Yoshiaki; Hata, Yoshinobu; Matsuoka, Shinnichi; Nakajima, Nobuhisa; Ito, Toichi; Osada, Tadahiro; Sano, Fumio

    2004-01-01

    Although utility of three-dimensional (3D) helical CT for preoperative examination of breast cancer has been discussed, the accuracy of the helical CT in diagnosing breast cancer has not been fully evaluated. In this study 56 malignant and 28 benign breast tumors were evaluated preoperatively with 3D-helical CT, and their imaging results were compared with pathological findings of surgical specimens. Helical CT identified the presence of malignancy in 54 out of the 56 cancer cases tested and the sensitivity and specificity in distinguishing between malignant and benign tumors were 82% and 57%, respectively. The sensitivity and specificity in diagnosing the presence of metastatic axillary lymph nodes using helical CT were 70% and 80%, respectively. The sensitivity and specificity in diagnosing the presence of extensive intraductal component (EIC) using helical CT were 71% and 86%, respectively. Helical CT visualized all of the tumors in multifocal breast cancer cases. In conclusion, 3D-helical CT is a useful modality for preoperative examination of breast cancer, especially for assessing axillary lymph node status, and EIC, and will be helpful for conducting sentinel lymph node biopsy (SNLB) and breast-conserving surgery. (author)

  5. Diagnosis of deep vein thrombosis using multi-detector helical CT

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    Kimura, Masashi; Minamiguchi, Hiroki; Sahara, Shinya [Wakayama Medical Coll. (Japan)] [and others

    2002-11-01

    The purpose of this study was to evaluate the usefulness of multi-detector helical CT (MDHCT) with contrast medium in the diagnosis of deep vein thrombosis (DVT). The bilateral veins of the dorsal pedis in 45 patients (12 men, 33 women; average age, 64 years) under clinical suspicion of DVT were first punctured using 22-G needles. Then CT scanning from the level of the foot to the inferior vena cava was started 20 sec after the initial injection of 200 mL of dilute contrast medium (50 mL nonionic iodinated contrast medium of 300 mgI/mL and 150 mL saline) at a rate of 5 mL/sec. Two patients were excluded because of unsuccessful venous puncture. The average scanning time in 43 patients was 38.5{+-}7.9 seconds. Images of veins from the foot to the inferior vena cava were clearly demonstrated in each case. MDHCT showed DVT in 32 cases and patent deep vein in 11 cases. Simultaneous venography of the lower extremity in 18 patients clearly visualized DVT at the same level detected by contrast MDHCT. MDHCT for the diagnosis of DVT has the advantages of wider scanning rage, shorter scanning time, and finer Z-axis resolution than the other diagnostic modalities. (author)

  6. Diagnosis of deep vein thrombosis using multi-detector helical CT

    International Nuclear Information System (INIS)

    Kimura, Masashi; Minamiguchi, Hiroki; Sahara, Shinya

    2002-01-01

    The purpose of this study was to evaluate the usefulness of multi-detector helical CT (MDHCT) with contrast medium in the diagnosis of deep vein thrombosis (DVT). The bilateral veins of the dorsal pedis in 45 patients (12 men, 33 women; average age, 64 years) under clinical suspicion of DVT were first punctured using 22-G needles. Then CT scanning from the level of the foot to the inferior vena cava was started 20 sec after the initial injection of 200 mL of dilute contrast medium (50 mL nonionic iodinated contrast medium of 300 mgI/mL and 150 mL saline) at a rate of 5 mL/sec. Two patients were excluded because of unsuccessful venous puncture. The average scanning time in 43 patients was 38.5±7.9 seconds. Images of veins from the foot to the inferior vena cava were clearly demonstrated in each case. MDHCT showed DVT in 32 cases and patent deep vein in 11 cases. Simultaneous venography of the lower extremity in 18 patients clearly visualized DVT at the same level detected by contrast MDHCT. MDHCT for the diagnosis of DVT has the advantages of wider scanning rage, shorter scanning time, and finer Z-axis resolution than the other diagnostic modalities. (author)

  7. Helical CT defecography

    International Nuclear Information System (INIS)

    Ferrando, R.; Fiorini, G.; Beghello, A.; Cicio, G.R.; Derchi, L.E.; Consigliere, M.; Resasco, M.; Tornago, S.

    1999-01-01

    The purpose of this work is to investigate the possible role of Helical CT defecography in pelvic floor disorders by comparing the results of the investigations with those of conventional defecography. The series analyzed consisted of 90 patients, namely 62 women and 28 men, ranging in age 24-82 years. They were all submitted to conventional defecography, and 18 questionable cases were also studied with Helical CT defecography. The conventional examination was performed during the 4 standard phases of resting, squeezing, Valsalva and straining; it is used a remote-control unit. The parameters for Helical CT defecography were: 5 mm beam collimation, pitch 2, 120 KV, 250 m As and 18-20 degrees gantry inclination to acquire coronal images of the pelvic floor. The rectal ampulla was distended with a bolus of 300 mL nonionic iodinated contrast agent (dilution: 3g/cc). The patient wore a napkin and was seated on the table, except for those who could not hold the position and were thus examined supine. Twenty-second helical scans were performed at rest and during evacuation; multiplanar reconstructions were obtained especially on the sagittal plane for comparison with conventional defecographic images. Coronal Helical CT defecography images permitted to map the perineal floor muscles, while sagittal reconstructions provided information on the ampulla and the levator ani. To conclude, Helical CT defecography performed well in study of pelvic floor disorders and can follow conventional defecography especially in questionable cases [it

  8. Rupture of an aneurysm of the coronary sinus of Valsalva: diagnosis by helical CT angiography

    International Nuclear Information System (INIS)

    Azarine, A.; Lions, C.; Beregi, J.P.; Koussa, M.

    2001-01-01

    A 75-year-old man presented with a 5-day history of upper chest discomfort. On auscultation, there was a systolic murmur in the left parasternal area that radiated to the apex. Electrocardiography showed flat T waves in the anterior precordial leads. Chest X ray revealed mediastinal enlargement. Transthoracic echocardiography showed a dilated proximal ascending aorta with moderate aortic regurgitation. A contrast-enhanced helical CT scan, performed to eliminate an aortic dissection, showed a ruptured left coronary sinus of Valsalva aneurysm, confirmed at surgery. This case highlights the fact that helical CT, in patients with suspected aortic dissection, may reveal other pathology that accounts for the clinical presentation. (orig.)

  9. Rupture of an aneurysm of the coronary sinus of Valsalva: diagnosis by helical CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Azarine, A.; Lions, C.; Beregi, J.P. [Dept. of Vascular Surgery, Hopital Cardiologique, CHRU de Lille (France); Koussa, M. [Dept. of Vascular Radiology, Hopital Cardiologique, CHRU de Lille (France)

    2001-08-01

    A 75-year-old man presented with a 5-day history of upper chest discomfort. On auscultation, there was a systolic murmur in the left parasternal area that radiated to the apex. Electrocardiography showed flat T waves in the anterior precordial leads. Chest X ray revealed mediastinal enlargement. Transthoracic echocardiography showed a dilated proximal ascending aorta with moderate aortic regurgitation. A contrast-enhanced helical CT scan, performed to eliminate an aortic dissection, showed a ruptured left coronary sinus of Valsalva aneurysm, confirmed at surgery. This case highlights the fact that helical CT, in patients with suspected aortic dissection, may reveal other pathology that accounts for the clinical presentation. (orig.)

  10. Clinical applications for multiplanar- and three-dimensional-reconstructions by helical-CT for the diagnosis of acetabular fractures

    International Nuclear Information System (INIS)

    Stroszczynski, C.; Schedel, H.; Stoeckle, U.; Wellmann, A.; Beier, J.; Wicht, L.; Hoffmann, R.; Felix, R.

    1996-01-01

    This review describes recent visualizations of computed tomography for the diagnosis of acetabular fractures. The techniques of conventional and helical-CT for the imaging of the acetabulum are compared. Furthermore, the different methods of multiplaner and three-dimensional reconstructions e.g. shaded surface display, maximum intensity projection, and volume rendering are presented. Figures of multiplanar and three-dimensional imaging for fractures of the pelvis is discussed. (orig.) [de

  11. The helical three-dimensional CT in the diagnosis of torticollis with occipitocondylar hypoplasia

    International Nuclear Information System (INIS)

    Ilkko, E.; Tikkakoski, T.; Pyhtinen, J.

    1998-01-01

    Congenital anomalies of the atlanto-occipital and atlantoaxial joints are rare. Those most commonly reported are atlantoaxial instability, basilar impression, anomalies of the odontoid process, laxity of the transverse atlantal ligament and atlanto-occipital fusion. Occipital condylar hypoplasia is infrequent and difficult to recognise. We recently diagnosed it using helical 3D CT in association with torticollis in two patients. The first patient had a several year history of torticollis. The second patient had acute cervical lymphadenitis associated with post-operative torticollis. 3D CT distinctly revealed atlantoaxial subluxation with hypoplasia of the occipital condyles in both cases. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  12. The helical three-dimensional CT in the diagnosis of torticollis with occipitocondylar hypoplasia

    International Nuclear Information System (INIS)

    Ilkko, E.; Tikkakoski, T.; Pyhtinen, J.

    1998-01-01

    Congenital anomalies of the atlanto-occipital and atlantoaxial joints are rare. Those most commonly reported are atlantoaxial instability, basilar impression, anomalies of the odontoid process, laxity of the transverse atlantal ligament and atlanto-occipital fusion. Occipital condylar hypoplasia is infrequent and difficult to recognise. We recently diagnosed it using helical 3D CT in association with torticollis in two patients. The first patient had a several year history of torticollis. The second patient had acute cervical lymphadenitis associated with post-operative torticollis. 3D CT distinctly revealed atlantoaxial subluxation with hypoplasia of the occipital condyles in both cases

  13. Diagnosis of nutcracker syndrome of the left renal vein. Value of the corticomedullary phase of helical CT

    International Nuclear Information System (INIS)

    Igari, Hidenori

    2001-01-01

    The clinical significance of the corticomedullary phase of helical CT in the diagnosis of nutcracker syndrome of the left renal vein (LRV) was evaluated. A total of 38 patients with hematuria of unknown origin (12 men and 26 women, mean age 24 years [range: 18-32 years]) were examined by helical CT of the kidneys, retrograde left renal venography, and measurement of renocaval pressure gradients. The sensitivity and specificity of the corticomedullary and nephrographic phases of helical CT for detecting the nutcracker syndrome were determined. The nutcracker syndrome was diagnosed on the basis of the renography findings combined with pressure measurements in 19 patients: 12 with LRV hypertension and collateral veins, 1 with hypertension and no collateral veins, and 6 with collateral veins and normal pressure gradients or borderline hypertension. Both the corticomedullary- and nephrographic-phase images revealed distended LRVs in 26 (68%) of the 38 patients. The LRV mean attenuation values in the corticomedullary phase (164±22 Hounsfield units [H], range: 138-209 H) was significantly greater (p<0.001) than in the nephrographic phase (80±14 H, range: 62-100 H). During the corticomedullary phase, opacified blood from the renal vein was mixed with unopacified blood in the IVC. In the nephrographic phase, however, the IVC was enhanced homogeneously, but only slightly. Corticomedullary-phase imaging detected collateral veins that exhibited early enhancement, indicating retrograde flow from the LRVs in 15 out of 18 patients (83% of those with collateral veins), while the nephrographic-phase imaging revealed collateral veins in 8 patients (44% of those with collateral veins). The sensitivity and specificity of the corticomedullary-phase scan for detecting the nutcracker syndrome were 79% and 100%, respectively, as opposed to 42% and 100%, respectively, for the nephrographic phase. Retrograde flow from the LRV into the collateral veins in the corticomedullary phase is a

  14. A qualitative diagnosis of stapes lesions by helical 3-dimensional CT

    International Nuclear Information System (INIS)

    Kawaue, Akifumi; Yamanaka, Noboru; Kuki, Kiyonori; Nishimura, Michihiko

    2001-01-01

    To evaluate the usefulness of 3D-CT combined with super-selective stapes's image processing (3D-SS) for the qualitative diagnosis of stapes lesions, a new parameter, the crus index, was designed and applied to CT image diagnosis of conductive hearing loss. The crus index was designed as a new parameter indicating the average of changing rate of cross section area of crus image when the lower thresholed of CT window width reduced by 100 H.U.. The crus index was calculated with 3D-SS in 5 ears with otosclerosis, in 5 ears with eroded long process of incus or crus of stapes, an ear with facial neurinoma (susp), an ear with soft density tissue on only stapes and 6 control ears and the diagnostic usefulness was evaluated as comparing the intra-/post-operative diagnosis. The crus index was significantly higher in ears with eroded long process of incus or crus of stapes (3.58+1.36) than otosclerosis (1.33+0.35) or controls (1.44+0.3). These data suggest that the crus index using 3D-SS may be a useful parameter in diagnosing conductive hearing loss. (author)

  15. Clinical application of helical CT colonography

    International Nuclear Information System (INIS)

    Zeng Huiliang; Zhu Xinjin; Liang Rujian; Liang Jianhao; Ou Weiqian; Wen Haomao

    2009-01-01

    Objective: To investigate the clinical value of 16-slice helical CT colonography in the diagnosis of colon tumor and polypus. Methods: 16-slice helical CT volumetric scanning was performed in 18 patients with colonic disease, including colonic tumor (n=16) and colonic polypus (n=2). 3D images, virtual endoscopy and multiplanar reformation were obtained in the AW4.1 workstation. CT appearances were compared with operation and fiberoptic colonoscopy. Results: Satisfied results were achieved from 18 patients, no difference found in results between CT colonography and operation in 16 patients with colonic tumor. Conclusion: 16-slice helical CT colonography is of great value in preoperative staging of colonic tumor and have a high value in clinical application. (authors)

  16. Helical CT for emergency patients with cerebrovascular diseases. Diagnosis of cerebral aneurysms with subarachnoid hemorrhage (SAH) by three-dimensional CT angiography (3D-CTA)

    International Nuclear Information System (INIS)

    Matsumoto, Masato; Satoh, Naoki; Kobayashi, Touru; Kodama, Namio; Nakano, Masayuki; Watanabe, Youichi; Fujii, Masayuki

    1996-01-01

    Recently, the usefulness of three-dimensional CT angiography (3D-CTA) using helical CT has been reported. Although 3D-CTA has been applied for neurosurgical diseases, especially for surgical planning, it has not done for emergency patients because of the long time required for image reconstruction and location of a helical CT scanner. We studied emergency patients with SAH, and compared the 3D-CTA with angiography and surgical findings, using TOSHIBA X vigor. Twenty-two patients with SAH were evaluated. The helical CT was performed for 55 seconds with a bolus injection of 90 ml non-ionic, iodinated contrast medium at a rate of 3 ml/sec with a delay of 20 sec. Angiography was carried out immediately after the helical CT. Eighteen of 22 cases were operated on urgently. We were able to create the 3D-CTA in about 7 minutes, and diagnose aneurysms by the 3D-CTA before angiography. The 3D-CTA was able to demonstrate 30 of 31 aneurysms including 9 unruptured aneurysms. An unruptured internal carotid-posterior communicating artery aneurysm 1.3 mm in diameter and associated with a ruptured aneurysm was not detected by either the 3D-CTA or angiography. On the other hand, an unruptured Acom aneurysm 0.8 mm in diameter and associated with a ruptured aneurysm could be detected by the: 3D-CTA, but not by angiography. The 3D-CTA gave us useful information concerning the anatomical relationship of the aneurysm, its neck and parent artery, and the surrounding branches. There were no complications or side effects associated with the helical CT scan. Although the 3D-CTA requires further development of visualization of small arteries less than 1 mm in diameter, such as perforating arteries, subtraction technique of bony structure, and a method for checking cervical arteries, it is useful for diagnosis of emergency patients with SAH and urgent operations. We believe that an operation might be performed by only the 3D-CTA without the angiography in the near future. (author)

  17. Helical CT for emergency patients with cerebrovascular diseases. Diagnosis of cerebral aneurysms with subarachnoid hemorrhage (SAH) by three-dimensional CT angiography (3D-CTA)

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Masato; Satoh, Naoki; Kobayashi, Touru; Kodama, Namio; Nakano, Masayuki; Watanabe, Youichi; Fujii, Masayuki [Fukushima Medical School (Japan)

    1996-05-01

    Recently, the usefulness of three-dimensional CT angiography (3D-CTA) using helical CT has been reported. Although 3D-CTA has been applied for neurosurgical diseases, especially for surgical planning, it has not done for emergency patients because of the long time required for image reconstruction and location of a helical CT scanner. We studied emergency patients with SAH, and compared the 3D-CTA with angiography and surgical findings, using TOSHIBA X vigor. Twenty-two patients with SAH were evaluated. The helical CT was performed for 55 seconds with a bolus injection of 90 ml non-ionic, iodinated contrast medium at a rate of 3 ml/sec with a delay of 20 sec. Angiography was carried out immediately after the helical CT. Eighteen of 22 cases were operated on urgently. We were able to create the 3D-CTA in about 7 minutes, and diagnose aneurysms by the 3D-CTA before angiography. The 3D-CTA was able to demonstrate 30 of 31 aneurysms including 9 unruptured aneurysms. An unruptured internal carotid-posterior communicating artery aneurysm 1.3 mm in diameter and associated with a ruptured aneurysm was not detected by either the 3D-CTA or angiography. On the other hand, an unruptured Acom aneurysm 0.8 mm in diameter and associated with a ruptured aneurysm could be detected by the: 3D-CTA, but not by angiography. The 3D-CTA gave us useful information concerning the anatomical relationship of the aneurysm, its neck and parent artery, and the surrounding branches. There were no complications or side effects associated with the helical CT scan. Although the 3D-CTA requires further development of visualization of small arteries less than 1 mm in diameter, such as perforating arteries, subtraction technique of bony structure, and a method for checking cervical arteries, it is useful for diagnosis of emergency patients with SAH and urgent operations. We believe that an operation might be performed by only the 3D-CTA without the angiography in the near future. (author)

  18. The value of multislice helical CT in the diagnosis of the rib micro-fracture

    International Nuclear Information System (INIS)

    Wang Shuli; Wang Linsen; Sun Dingyuan; Deng Xin; Geng Xin; Li Jian; Liu Zhigang; Guo Lin; Jia Zhihong

    2005-01-01

    Objective: To evaluate the clinical value of MSCT with thin-section reconstruction and curved multiplanar reformation of rib micro-fracture. Methods: Thirty-eight patients suspected ribs fracture by clinical examination, which had negative appearance in X-ray film, were performed with MSCT scan with thin-section reconstructed and curved multiplanar reformation. The imaging of 5 mm, 1 mm thickness and curved reformatted imags were analysed by three groups of radiologists respectively. Results: Of the 38 patients, 26 patients were demonstrated ribs fracture with 1 mm thin-section reconstructed and curved multiplanar reformatted CT imaging, which were classified as complete fracture in 18 ribs and incomplete fracture in 41 ribs. The ends of the fractures displacement located within a distance of double-thickness of the cortex of the complete ribs fracture. With 5 mm thickness imaging, the accuracy of the diagnosis was 86.4%, 89.8% and 94.9% by three groups radiologists, respectively. Conclusion: The rib fracture is very common in clinic, the incomplete and non evident displacement complete ribs fracture are difficult to be diagnosed by plain radiography. The MSCT can produce a large range volume information scan. Thin-section reconstructed and curved multiplanar reformatted imaging should be the effective method in diagnosis of ribs fracture. The total rib pattern and location, extend of all the ribs fracture in this cases can be displayed in one scan by the curved multiplanar reformatted imaging. (authors)

  19. Helical CT in acute lower gastrointestinal bleeding

    International Nuclear Information System (INIS)

    Ernst, Olivier; Leroy, Christophe; Sergent, Geraldine; Bulois, Philippe; Saint-Drenant, Sophie; Paris, Jean-Claude

    2003-01-01

    The purpose of this study was to assess the usefulness of helical CT in depicting the location of acute lower gastrointestinal bleeding. A three-phase helical CT of the abdomen was performed in 24 patients referred for acute lower gastrointestinal bleeding. The diagnosis of the bleeding site was established by CT when there was at least one of the following criteria: spontaneous hyperdensity of the peribowel fat; contrast enhancement of the bowel wall; vascular extravasation of the contrast medium; thickening of the bowel wall; polyp or tumor; or vascular dilation. Diverticula alone were not enough to locate the bleeding site. The results of CT were compared with the diagnosis obtained by colonoscopy, enteroscopy, or surgery. A definite diagnosis was made in 19 patients. The bleeding site was located in the small bowel in 5 patients and the colon in 14 patients. The CT correctly located 4 small bowel hemorrhages and 11 colonic hemorrhages. Diagnosis of the primary lesion responsible for the bleeding was made in 10 patients. Our results suggest that helical CT could be a good diagnostic tool in acute lower gastrointestinal bleeding to help the physician to diagnose the bleeding site. (orig.)

  20. Helical CT of ureteral disease

    International Nuclear Information System (INIS)

    Cikman, Pablo; Bengio, Ruben; Bulacio, Javier; Zirulnik, Esteban; Garimaldi, Jorge

    2000-01-01

    Among the new applications of helical CT is the study of the ureteral pathology. The objective of this paper was to evaluate patients with suspected pathology of this organ and the repercussion in the therapeutic plans. We studied 23 patients with a helical CT protocol, without IV contrast injection and performed multiplanar reconstruction (MPR). We called this procedure Pielo CT. Thirteen ureteral stones were detected, 6 calculi, 2 urinary tract tumors, dilatation of the system in a patient with neo-bladder. In 2 patients, in whom ureteral pathology was ruled out, we found other alterations that explained the symptoms, (gallbladder stones, disk protrusion). The Pielo CT let decide a therapeutical approach in 20 or 21 patients with ureteral pathology. (author)

  1. Dynamic helical CT mammography of breast cancer

    International Nuclear Information System (INIS)

    Yamamoto, Akira; Fukushima, Hitoshi; Okamura, Ryuji; Nakamura, Yoshiaki; Morimoto, Taisuke; Urata, Yoji; Mukaihara, Sumio; Hayakawa, Katsumi

    2006-01-01

    The purpose of this study was to determine whether dynamic helical computed tomography (CT)-mammography could assist in selecting the most appropriate surgical method in women with breast cancer. Preoperative contrast-enhanced helical CT scanning of the breast was performed on 133 female patients with suspicion of breast cancer at the same time as clinical, mammographic, and/or ultrasonographic examinations. The patients were scanned in the prone position with a specially designed CT-compatible device. A helical scan was made with rapid intravenous bolus injection (3 ml/s) of 100 ml of iodine contrast material. Three-dimensional maximum intensity projection (MIP) images were reconstructed, and CT findings were correlated with surgical and histopathological findings. Histopathological analysis revealed 84 malignant lesions and seven benign lesions. The sensitivity, specificity, and accuracy levels of the CT scanning were 94.6%, 58.6%, and 78.9%. Helical scanning alone revealed additional contralateral carcinomas in three of four patients and additional ipsilateral carcinomas in three of five patients. However, the technique gave false-positive readings in 24 patients. The preoperative CT-mammogram altered the surgical method in six patients. Dynamic helical CT-mammography in the prone position may be one of the choices of adjunct imaging in patients with suspected breast cancer scheduled for surgery. (author)

  2. Helical CT of congenital ossicular anomalies

    International Nuclear Information System (INIS)

    Osada, Hisato; Machida, Kikuo; Honda, Norinari

    2001-01-01

    Since January 1996 to December 2000, 26 cases of congenital ossicular anomaly could be diagnosed with helical CT. All cases were unilateral. In 8 patients with malformation of the external ear, CT showed malleoincudal fixation (n=5), malleoincudal fixation and deformed incuts long process (n=1), deformed incus long process (n=1), and partial fusion of malleus neck and incus long process (n=1). In 18 patients with normal external ear, CT showed defect of the incus long process (n=5), defect of both the incus long process and stapes superstructure (n=8, 2 patients with congenital cholesteatoma, 1 with hypoplastic oval window), defect of the stapes superstructure (n=2, 1 patient with oval window absence), defect of the malleus manubrium (n=1), ossification of the stampede's tendon (n=1), and monopod stapes (n=1). Helical CT can evaluate the auditory ossicular chain in detail and is useful for diagnosing congenital ossicular anomaly. (author)

  3. Unenhanced helical CT in the investigation of acute flank pain

    International Nuclear Information System (INIS)

    Colistro, Robert; Torreggiani, William C.; Lyburn, Iain D.; Harris, Alison C.; Al-Nakshabandi, Nizar A.; Nicolaou, Savvas; Munk, Peter L.

    2002-01-01

    Unenhanced helical CT has emerged as the imaging technique of choice for the investigation of patients presenting with acute flank pain and suspected nephroureteric stone disease. There are several signs identifiable on unenhanced CT that support a diagnosis of stone disease. However, there are many pitfalls, that may confound a correct diagnosis. Some of the common pitfalls, together with methods to avoid such occurrences, will be discussed. A review of some of the common alternative diagnoses that may mimic the symptoms of nephroureteric stone disease is illustrated. Colistro, R. et al (2002)

  4. Colonic metastasis from renal cell carcinoma: helical-CT demonstration

    International Nuclear Information System (INIS)

    Diaz-Candamio, M.J.; Pombo, S.; Pombo, F.

    2000-01-01

    Clinically evident colonic metastasis from renal cell carcinoma (RCC) is rare. In the present study a hypervascular sigmoid mass was demonstrated on arterial-phase helical CT using a water enema in a patient who had suffered left nephrectomy 8 years previously for RCC. The intense and early enhancement of the lesion suggested the possibility of a solitary colonic metastasis from RCC, a diagnosis which was pathologically confirmed. (orig.)

  5. Helical CT of traumatic injuries of the thoracic aorta

    International Nuclear Information System (INIS)

    Mengozzi, E.; Burzi, M.; Miceli, M.; Lipparini, M.; Sartoni Galloni, S.

    2000-01-01

    Acute thoracic aortic injuries account for up to 10-20% of fatalities in high-speed deceleration road accidents and have an estimated immediate fatality rate of 80-90%. Untreated survivors to acute trauma (10-20%) have a dismal prognosis: 30% of them die within 6 hours, 40-50% die within 24 hours, and 90% within 4 months. It was investigated the diagnostic accuracy of Helical Computed Tomography (Helical CT) in acute traumatic injuries of the thoracic aorta, and the role of this technique in the diagnostic management of trauma patients with a strong suspicion of aortic rupture. It was compared retrospectively the chest Helical CT findings of 256 trauma patients examined June 1995 through August 1999. Chest Helical CT examinations were performed according to trauma score, to associated traumatic lesions and to plain chest radiographic findings. All the examinations were performed with no intravenous contrast agent administration and the pitch 2 technique. After a previous baseline study, contrast-enhanced scans were acquired with pitch 1 in 87 patients. Helical CT showed aortic lesions in 9 of 256 patients examined. In all the 9 cases it was found a mediastinal hematoma and all of them had positive plain chest radiographic findings of mediastinal enlargement. Moreover, in 6 cases aortic knob blurring was also evident on plain chest film and in 5 cases depressed left mainstem bronchus and trachea deviation rightwards were observed. All aortic lesions were identified on axial scans and located at the isthmus of level. Aortic rupture was always depicted as pseudo diverticulum of the proximal descending tract and intimal flap. It was also found that periaortic hematoma in 6 cases and intramural hematoma in 1 case. There were non false positive results in the series: 7 patients with Helical CT diagnosis of aortic rupture were submitted to conventional aortography that confirmed both type and extension of the lesions as detected by Helical CT, and all findings were

  6. Aortic non communicating dissections. A study with helical CT

    International Nuclear Information System (INIS)

    Midiri, M.; Strada, A.; Stabile Ianora, A.A.; Rotondo, A.; Angelelli, G.; D'Agostino, D.; De Luca Tupputi Schinosa, L.

    2000-01-01

    The evaluate the signs of aortic intramural hematoma with helical CT and the diagnostic role of this technique in patients with this condition. It was reviewed the CT findings of 396 patients submitted to emergency examinations for suspected aortic dissection from 1995 to 1999. Only 18 patients (6 women and 12 men) had CT signs of aortic intramural hematoma. Helical CT studies were carried out with the following parameters: slice thickness 10 mm, reconstruction index 10, feed 1.5 mm, conventional algorithm with minimum values of 130 kV and 125mA. All patients were examined with dynamic contrast-enhanced CT, before and after a power injection of 130 mL ionic contrast material. It was studied: hematoma localization and longitudinal extension; thickness and density of aortic wall; presence and location of intimal calcifications; integrity of intimal wall; hemo mediastinum and/or hemo thorax. Aortic wall thickening appeared as a high density crescent-shaped area at baseline CT and had low density on enhanced images in all patients. Thickening was eccentric in 14/18 patients and concentric in 4/18 only; it always exceeded 4 mm. It was found some intimal calcifications in 8 patients and hemo thorax and/or hemo mediastinum in 9 patients. A patient with type A hematoma died of cardiac tamponade a few hours after CT diagnosis. Six patients (5 type B and 1 type A) underwent anti-hypertensive treatment and radiological follow-up. Eleven patients (6 type A and 5 type B) underwent prosthesis replacement and 5 of them (3 type A and 2 type B) died of postoperative complications. In the 5 type B patients surgery was performed because of treatment-resistant pain and of the onset of ischemic complications to abdominal organs caused by involvement of the main collateral branches of the aorta. One patient with type A hematoma was submitted to drug treatment because it was judged unresectable. Intramural hematoma of the aorta is a distinct pathological entity, which should not be

  7. Comparison of AMI-25 enhanced MRI and helical dynamic CT in the detection of hepatic lesions

    International Nuclear Information System (INIS)

    Saitou, Kazuhiro; Matsuda, Hiromichi; Fukushima, Hiroaki; Kanzaki, Hiroshi; Hirose, Takashi; Karizaki, Dai; Abe, Kimihiko; Amino, Saburou

    1994-01-01

    We performed AMI-25 enhanced MRI and helical dynamic CT in 12 cases of hepatic lesions. Nine of these were hepatocellular carcinomas. Two cases were metastatic liver tumors (the primary lesion was gastric in one and the other was gallbladder cancer). One case was suspected to be adenomatous hyperplasia. Thirty-two lesions were detected in T2-weighted SE images before AMI-25 administration, while 46 lesions were detected in AMI-25 enhanced MRI images. In particular, AMI-25 enhanced MRI was superior to plain MRI in lesions less than 10 mm in size. A total of 48 lesions were detected in helical dynamic CT. Although AMI-25 enhanced MRI almost equaled helical dynamic CT in the detection of liver tumors, helical dynamic CT was slightly superior to AMI-25 enhanced MRI in the detection of subphrenic lesions. It was possible to know the hemodynamics in each hepatic lesion by helical dynamic CT. AMI-25 enhanced MRI was useful to know the inclusion of reticuloendothelial system, and that yielded different diagnoses in adenomatous hyperplasia and well differentiated hepatocellular carcinoma. Helical dynamic CT was useful for qualitative diagnosis. Both AMI-25 enhanced MRI and helical dynamic CT contributed to the detection of liver tumor and qualitative diagnosis. (author)

  8. Patterns of uterine enhancement with helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, H.; Loyer, E.M.; Charnsangavej, C. [Department of Diagnostic Radiology, Box 57, The University of Texas, M.D. Anderson Cancer Center, 1515 Holcombe Blvd. Houston, TX 77030 (United States); Minami, M. [Department of Radiology, Faculty of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-Ku, Tokyo 113 (Japan)

    1998-10-01

    Objective: The purpose of this study was to evaluate the enhancement characteristics of the normal uterine body and cervix using dynamic contrast-enhanced helical CT. Methods: Thirty-eight women scheduled for pelvic CT for non-gynecologic malignancies underwent dynamic contrast-enhanced helical CT of the pelvis. Data acquisition was during the arterial phase (30-45 s after the start of injection), the parenchymal phase (90-120 s after the start of injection), and delayed phase (3-9 min after the start of injection). The images were evaluated by four radiologists for the pattern of myometrial and cervical enhancement. Correlation was made with the age and menstrual status of the patients. Results: In the uterine body, three types of enhancement were observed. Type 1 enhancement, seen in 16 patients (42%), was characterized by the visualization of a subendometrial zone of enhancement, 30-120 s after the start of injection. Eight of these patients also showed an enhancing zone in the outer myometrium. Both zones were transitory, and in all cases, the uterus became homogeneous in the delayed phase. This pattern was seen predominantly in premenopausal women with a mean age of 34 years. Type 2 enhancement, seen in 17 cases (45%), was defined by the absence of subendometrial enhancement in the early phase. Enhancement was either diffuse from the outset or originated in the outer myometrium. This pattern was seen nearly equally in premenopausal and postmenopausal women with a mean age of 40 years. Type 3 enhancement was seen in five postmenopausal patients (13%) with a mean age of 53 years and was characterized by faint diffuse enhancement. In the cervix, a zonal pattern of enhancement defining inner and outer stroma was seen in 23 patients (61%). Fifteen patients were premenopausal and eight were postmenopausal. Conclusion: In this study, we have shown a transitory zonal distribution of the contrast in the myometrium and cervix using dynamic contrast-enhanced helical CT

  9. Patterns of uterine enhancement with helical CT

    International Nuclear Information System (INIS)

    Kaur, H.; Loyer, E.M.; Charnsangavej, C.; Minami, M.

    1998-01-01

    Objective: The purpose of this study was to evaluate the enhancement characteristics of the normal uterine body and cervix using dynamic contrast-enhanced helical CT. Methods: Thirty-eight women scheduled for pelvic CT for non-gynecologic malignancies underwent dynamic contrast-enhanced helical CT of the pelvis. Data acquisition was during the arterial phase (30-45 s after the start of injection), the parenchymal phase (90-120 s after the start of injection), and delayed phase (3-9 min after the start of injection). The images were evaluated by four radiologists for the pattern of myometrial and cervical enhancement. Correlation was made with the age and menstrual status of the patients. Results: In the uterine body, three types of enhancement were observed. Type 1 enhancement, seen in 16 patients (42%), was characterized by the visualization of a subendometrial zone of enhancement, 30-120 s after the start of injection. Eight of these patients also showed an enhancing zone in the outer myometrium. Both zones were transitory, and in all cases, the uterus became homogeneous in the delayed phase. This pattern was seen predominantly in premenopausal women with a mean age of 34 years. Type 2 enhancement, seen in 17 cases (45%), was defined by the absence of subendometrial enhancement in the early phase. Enhancement was either diffuse from the outset or originated in the outer myometrium. This pattern was seen nearly equally in premenopausal and postmenopausal women with a mean age of 40 years. Type 3 enhancement was seen in five postmenopausal patients (13%) with a mean age of 53 years and was characterized by faint diffuse enhancement. In the cervix, a zonal pattern of enhancement defining inner and outer stroma was seen in 23 patients (61%). Fifteen patients were premenopausal and eight were postmenopausal. Conclusion: In this study, we have shown a transitory zonal distribution of the contrast in the myometrium and cervix using dynamic contrast-enhanced helical CT

  10. Helical CT imaging of clinically suspected appendicitis: Correlation of CT and histological findings

    International Nuclear Information System (INIS)

    Wong, S.K.; Chan, L.P.; Yeo, A.

    2002-01-01

    PURPOSE: The diagnosis of appendicitis is traditionally made on the basis of clinical findings supported by laboratory results. The aim of our study was to determine the accuracy and feasibility of using a relatively new technique of computed tomography (CT) using only colonic contrast medium. MATERIALS AND METHODS: A total of 50 patients clinically diagnosed as having appendicitis were prospectively examined before surgery with thin-collimation helical CT from the L3 level to the acetabular roof with only rectally administered colon contrast medium. The hard copy CT images were reviewed jointly by two radiologists and a consensus was reached for each patient. The results were then compared with the surgical and histological findings at appendicectomy. RESULTS: There were 35 true-positives, one false-positive, 12 true-negatives and two false-negatives for CT. This yielded an accuracy of 94%, sensitivity of 95%, specificity of 92%, positive predictive value of 97% and negative predictive value of 86%. The appendix was identified in 45 patients (90%) and obscured by an inflammatory mass in the remaining five. An alternative diagnosis was found in 10 of 12 normal CT examinations (83%). CONCLUSION: Helical CT with rectal contrast medium is a quick, well tolerated and accurate test to diagnose appendicitis. It can offer alternative, possibly non-surgical diagnosis in patients who would otherwise have undergone laparotomy. Wong, S.K. et al. (2002)

  11. CT diagnosis of hepatoma

    Energy Technology Data Exchange (ETDEWEB)

    Itai, Yuji [Tokyo Univ. (Japan). Faculty of Medicine

    1982-04-01

    In hepatocellular carcinoma, present status of CT diagnosis was discussed. Hepatocellular carcinoma is sometimes imaged in same concentration as that of surrounding tissues, and the detection rate ranged from 79 to 94%. The rate of differential diagnosis between primary and metastatic carcinoma was only 83% (includes 22% of false diagnosis) using contrast enhancement. The rates of detection of hepatocellular carcinoma and metastatic one were also only 87% and 75%, respectively, even by the combined use of arterial infusion CT and dynamic CT. However, the CT images is reproducible, and is supplemented by the information of US. Thus, the combination of these methods is useful in diagnosing the presence, extension, and nature of liver carcinoma.

  12. Diagnosis of acute flank pain caused by ureteral stones: value of combined direct and indirect signs on IVU and unenhanced helical CT

    International Nuclear Information System (INIS)

    Wang, Li-Jen; Wong, Yon-Cheong; Ng, Chip-Jin; Chen, Jih-Chang; Chiu, Te-Fa

    2004-01-01

    The aim of this study was to assess the usefulness of combined direct and indirect signs on intravenous urography (IVU) and unenhanced helical computed tomography (UHCT) for the diagnosis of ureteral stones in emergency patients with acute flank pain. During an 8-month period, 82 emergency patients with acute flank pain undergoing IVU and UHCT with sufficient clinical follow-up formed the study group. The presence or absence of direct sign (visualization of ureteral stones) and indirect signs on IVU and UHCT was recorded. The diagnostic accuracy of each direct/indirect sign and their combination for the diagnosis of ureteral stones on IVU and UHCT were analyzed and compared. Of the 82 patients, 66 had ureteral stones, four had passed urinary stones prior to imaging and 12 had other diseases. The diagnostic accuracies of direct signs on IVU and UHCT for the diagnosis of ureteral stones were 79.3 and 98.8%, respectively, which was more accurate than that of any single indirect sign on IVU and UHCT. However, the diagnostic accuracy of ureteral stones by IVU increased to 90.2% when using diagnostic criteria requiring the presence of a direct sign or at least three indirect signs, and by UHCT, it increased to 100% when using diagnostic criteria requiring the presence of a direct sign with at least one indirect sign. Therefore, for emergency patients with acute flank pain, the use of the above combinations of direct/indirect signs is useful as the diagnostic criterion for ureteral stones. (orig.)

  13. Helical CT for secondary screening of lung cancer

    International Nuclear Information System (INIS)

    Mori, Kiyoshi; Onishi, Tsukasa; Tominaga, Keigo; Kishiro, Izumi; Yokoyama, Kohki.

    1995-01-01

    Helical CT was used on a trial basis for secondary screening of lung cancer, and its clinical usefulness is discussed in this report. The subjects of 157 patients with abnormal shadows on plain chest X-ray images were chosen between November 1993 and August 1994. Imaging parameters used for screening CT were as follows: 50 mA, 120 kV, a couch-top movement speed of 20 mm/s, and a beam width of 10 mm. The entire lung field was scanned during a single breath-hold. Reconstructed images were generated at 10-mm intervals by the 180deg interpolation method, and films were produced. Images of the entire lung field were made during a single breath-hold in all patients. Abnormal shadows were detected in 73 of 157 patients by screening CT. These 73 patients included 14 with lung cancer, 53 with benign lesions, one under observation, and five others. The average diameter of the tumors was 11.1 mm. The lung cancers detected all arose in the periphery, and were classified into stage I (10 patients), stage IIIA (3 patients), and stage IV with bone metastases (1 patient). Lung cancers in clinical stage I (3 patients) and stage IV (1 patient) were difficult to see on plain chest X-ray films. We conclude that screening CT is useful for early diagnosis of lung cancer because the entire lung field can be imaged during a single breath-hold. Therefore, helical CT can be expected to be useful in screening for lung cancer. (author)

  14. Helical 3D-CT images of soft tissue tumors in the hand

    Energy Technology Data Exchange (ETDEWEB)

    Otani, Kazuhiro; Kikuchi, Hiraku; Tan, Akihiro; Hamanishi, Chiaki; Tanaka, Seisuke [Kinki Univ., Osaka-Sayama (Japan). School of Medicine

    2000-02-01

    X-ray, ultrasonograph CT, MRI and angiography are used to detect tumoral lesions. Recently, helical CT has been revealed to be a useful method for the diagnosis and preoperative evaluation of soft tissue tumors, by which high quality and accurate three dimensional (3D) images can be obtained quickly. We analyzed the preoperative 3D-CT images of soft tissue tumors in the hands of 11 cases (hemangioma in 6 cases, giant cell tumor, lipoma, angiofibroma, chondrosarcoma and malignant fibro-histiocytoma in one case each). Enhanced 3D-CT clearly visualized hemangiomas and solid tumors from the surrounding tissues. The tumors could easily be observed from any direction and color-coded according to the CT number. Helical 3D-CT was thus confirmed to be useful for the diagnosis and preoperative planning by indicating the details of tumor expansion into surrounding tissues. (author)

  15. Helical CT defecography; La defecografia con Tomografia Computerizzata spirale

    Energy Technology Data Exchange (ETDEWEB)

    Ferrando, R.; Fiorini, G.; Beghello, A.; Cicio, G.R.; Derchi, L.E.; Consigliere, M.; Resasco, M. [Genua Univ., Genua (Italy). Ist. di Radiologia, Cattedra R; Tornago, S. [Genua Univ. Genua (Italy). 2 Clinica Ortopedica

    1999-11-01

    The purpose of this work is to investigate the possible role of Helical CT defecography in pelvic floor disorders by comparing the results of the investigations with those of conventional defecography. The series analyzed consisted of 90 patients, namely 62 women and 28 men, ranging in age 24-82 years. They were all submitted to conventional defecography, and 18 questionable cases were also studied with Helical CT defecography. The conventional examination was performed during the 4 standard phases of resting, squeezing, Valsalva and straining; it is used a remote-control unit. The parameters for Helical CT defecography were: 5 mm beam collimation, pitch 2, 120 KV, 250 m As and 18-20 degrees gantry inclination to acquire coronal images of the pelvic floor. The rectal ampulla was distended with a bolus of 300 mL nonionic iodinated contrast agent (dilution: 3g/cc). The patient wore a napkin and was seated on the table, except for those who could not hold the position and were thus examined supine. Twenty-second helical scans were performed at rest and during evacuation; multiplanar reconstructions were obtained especially on the sagittal plane for comparison with conventional defecographic images. Coronal Helical CT defecography images permitted to map the perineal floor muscles, while sagittal reconstructions provided information on the ampulla and the levator ani. To conclude, Helical CT defecography performed well in study of pelvic floor disorders and can follow conventional defecography especially in questionable cases. [Italian] Scopo di questo lavoro e' ricercare un ruolo per la defeco-TC con apparecchiatura elicoidale nello studio delle malattie del pavimento pelvico confrontandola con i risultati consolidati della defecografia tradizionale. Si sono visionati 90 pazienti, 62 femmine e 28 maschi, con eta' compresa tra 24 e 82 anni, con defecografia tradizionale; di questi, 18 casi con diagnosi dubbia sono stati studiati anche con defeco-TC spirale

  16. Gynecological applications of helical CT using SmartPrep

    Energy Technology Data Exchange (ETDEWEB)

    Sakurada, Akira; Kakizaki, Dai; Abe, Kimihiko [Tokyo Medical Coll. (Japan)

    1999-11-01

    SmartPrep is software program for scanning a given region of interest (ROI) at optimal contrast density. An operator can arbitrarily define ROI and preset the CT value at which scanning should be started. After the injection of a contrast medium, system conducts continuous monitoring of the ROI and the operator starts helical scanning of the planned region when the present CT value has been reached. In comparison with conventional helical CT that requires a period of time from the beginning of contrast medium injection to the beginning of scanning, SmartPrep minimizes personal error and better depicts the artery-predominant phase under optimal conditions. In this study we examine the usefulness of contrast-enhanced helical CT using SmartPrep in the evaluation of gynecological disease. When the contrast medium was injected into the dorsal vein of the hand at a rate of 3 ml/sec, strong staining of pelvic arteries was observed in the CT images started at 17 to 23 sec after injection. The early-phase helical CT obtained under these conditions provided good depiction of lesions in cases of placenta accreta and invasive mole, as well as clear demonstration of tumor angiogenesis and evaluation of laterality in cases of cervical cancer. Comparison of the early and delayed phase also facilitated easier evaluation of lymph nodes than conventional comparison of simple and contrast-enhanced CT. The results thus suggest the usefulness of contrast-enhanced helical CT using SmartPrep in gynecology. (author)

  17. Mediastinal fibrosis with pulmonary artery obstruction; diagnosis and investigation with helical CT imaging including 3-dimensional reconstructions; Pulomonalarterienstenose bei aggresiver Mediastinalfibrose; Diagnostik und 3D-Darstellung mittels helikaler CT-Untersuchung

    Energy Technology Data Exchange (ETDEWEB)

    Kolbe, M. [Inst. fuer Diagnostische Radiologie, Kantonsspital Basel (Switzerland); Helwig, A. [Inst. fuer Diagnostische Radiologie, Kantonsspital Basel (Switzerland); Habicht, J.M. [Klinik fuer Herz-Torax-Chirurgie, Universitaetskliniken Basel (Switzerland); Steinbruch, W. [Inst. fuer Diagnostische Radiologie, Kantonsspital Basel (Switzerland)

    1997-07-01

    An aggressive mediastinal fibrosis was found in a 42-year-old female, suffering from dysphagia, stabbing pain in the chest, and an unclear weight loss. In this case, the rare combination of esophageal involvement, bronchial narrowing, and pulmonary artery obstruction could easily be demonstrated with a barium study and a helical CT examination including three-dimensional reconstructions. (orig.) [Deutsch] Wir stellen den Fall einer 42jaehrigen Patientin vor, welche zur Abklaerung einer zunehmenden Dysphagie, stechender Thoraxschmerzen und eines Gewichtsverlustes hospitalisiert wurde. Mittels klinischer und radiologischer Abklaerung konnte eine aggressive Mediastinalfibrose diagnostiziert werden. Die seltene Kombination einer Oesophaguseinengung mit Pulmonalarterienstenosen sowie einer Bronchuskompression konnte nichtinvasiv mittels Oesophagogramm und helikaler CT-Untersuchung zuverlaessig und schnell dargestellt werden. (orig.)

  18. CT Diagnosis of Appendicitis

    Directory of Open Access Journals (Sweden)

    Christopher Libby

    2017-01-01

    Full Text Available History of present illness: A 19-year-old male with no previous medical history presented with 7/10 non-radiating, constant, sharp, periumbilical pain associated with nausea, and four episodes of vomiting. He was seen at urgent care where his labs showed a WBC of 16,000/mcL. He was subsequently sent to the emergency department (ED for concern of appendicitis. Of note, his pain worsened with bumps during the drive to the ED. After arriving to the ED the pain migrated to the right lower quadrant. Computed tomography (CT revealed acute appendicitis and the patient was admitted to the surgery service and taken to the operating room (OR for an appendectomy. Significant findings: The CT abdomen/pelvis with IV contrast shows a dilated appendix (see red outline with thickened, hyperenhancing wall (see blue outline best visualized in the axial and coronal planes. Discussion: Appendicitis is a common diagnosis in the emergency department in patients presenting with abdominal pain, occurring most frequently in young adults with a peak incidence in those aged 10-19.1 Failure to quickly diagnose acute appendicitis can result in perforation rates as high as 80 percent.2 While the diagnosis of appendicitis can be made clinically, CT is a non-invasive modality that improves the detection of appendicitis with sensitivities of 88–100%, specificities of 91–99%, positive predictive values of 92–98%, negative predictive values of 95–100%, and accuracies of 94–98%.3-8 The major advantage of CT over both clinical exam and ultrasound is the ability of the radiologist to exclude acute appendicitis if the appendix appears normal. However, CT carries the risks associated with ionizing radiation. While previously there was some debate on the best choice for type of CT scan and use of IV and oral contrast, recent studies have shown that CT abdomen/pelvis with IV contrast alone is sufficient for diagnosis of appendicitis.9, 10

  19. The usefulness of three-dimensional helical CT for the detection of abnormalities of the auditory ossicles

    International Nuclear Information System (INIS)

    Gong, Honghan; Hiraishi, Kumiko; Uesugi, Yasuo; Shimizu, Tadafumi; Narabayashi, Isamu

    1996-01-01

    To evaluate the usefulness of three-dimensional (3D) helical CT for the detection of abnormalities of the auditory ossicles, 3D helical CT of the middle ear was performed in seven patients with hearing disorder. It revealed that 4 patients had congenital deficiency of the auditory ossicles, 2 patients with chronic otitis media had shortening of the incus and one patient with head injury had doubtful fracture of the incus. This study indicated that 3D helical CT of the middle ear can represent the auditory ossicles objectively and can offer detailed diagnosis. (author)

  20. Patellofemoral joint dysfunction. Combined diagnostic imaging evaluation (X-rays, 3D helical CT and MRI)

    International Nuclear Information System (INIS)

    Carrascosa, P.; Sanchez, F.; Mazzucco, J.; Capanay, C.; Carrascosa, J.

    2000-01-01

    The comprehensive study including 3D helical CT, Magnetic Resonance (MR) and X-ray exams provide a more complete diagnosis than those obtained through the conventional CT. We studied 43 patients with presumptive or certain diagnosis of patellofemoral instability. All the patients were studied by: a) Radiological pair; b) Tomography under extension and flexion, without and with contraction, using a helical CT equipment; and c) MRI STIR sequence in axial plane. The findings were classified as muscular lesion, cartilage lesion, bone and associated lesions (e.g. synovitis), statistically comparing both studies (comprehensive vs. conventional). The results allow us to accept the hypothesis that the comprehensive study provides a more complete diagnosis about the origin of the patellofemoral dysfunction. In 65% of the patients, the conventional study gave a negative result. Only in 35% of the cases the result was positive, but incomplete, showing only 35.3% of the pathological findings detected by the comprehensive study. (author)

  1. Helical CT in evaluation of the bronchial tree

    International Nuclear Information System (INIS)

    Perhomaa, M.; Laehde, S.; Rossi, O.; Suramo, I.

    1997-01-01

    Purpose: To establish a protocol for and to assess the value of helical CT in the imaging of the bronchial tree. Material and Methods: Noncontrast helical CT was performed in 30 patients undergoing fiberoptic bronchoscopy for different reasons. Different protocols were compared; they included overlapping 10 mm, 5 mm, or 3 mm slices and non-tilted, cephalad or caudal tilted images. Ordinary cross-sectional and multiplanar 2D reformats were applied for visualization of the bronchial branches. The effect of increasing the helical pitch was tested in one patient. Results: A total of 92.1-100% of the segmental bronchi present in the helical acquisitions were identified by the different protocols. The collimation had no significant impact on the identification of the bronchial branches, but utilization of 3-mm overlapping slices made it easier to distinguish the nearby branches and provided better longitudinal visualization of the bronchi in 2D reformats. The tilted scans illustrated the disadvantage of not covering all segmental bronchi in one breath-hold. An increase of the pitch from 1 to 1.5 did not cause noticeable blurring of the images. CT and bronchoscopic findings correlated well in the area accessible to bronchoscopy, but CT detected 5 additional pathological lesions (including 2 cancers) in the peripheral lung. Conclusion: Helical CT supplemented with bronchography-like 2D reformats provides an effective method complementary to bronchoscopy in the examination of the bronchial tree. (orig.)

  2. Significance of diagnosis of liver metastases from colorectal cancer by angio helical CT and intermittent hepatic arterial infusion chemotherapy after hepatic resection in terms of prognosis

    International Nuclear Information System (INIS)

    Hatsuse, Kazuo; Aoki, Hideki; Murayama, Michinori

    1997-01-01

    Seventy five cases had undergone hepatic resection for liver metastases from colorectal cancer from 1979 to 1994. Computed tomography during hepatic angiography (angio CT) was tried in 27 cases. At first, we compared detection ratios of angio CT for liver metastase to those of ultrasonography, conventional CT, and operative ultrasonography on these 27 cases. Next, the prognosis of seventy five cases was examined. They were divided into three groups; the HX group 29 cases with only hepatic resection; the HX+AP group of 19 cases with intermittent hepatic arterial infusion chemotherapy after hepatic resection; the angio CT group of 27 cases selected for hepatic resection by angio CT, followed by the same infusion chemotherapy as that given to the HX+AP group. Fifty metastases were diagnosed histopathologically in twenty seven cases that underwent hepatic resection after angio CT. Detection ratios for small metastases 1.0 cm or smaller in diameter were 8.3% with ultrasonography, 25% with CT, 75% with angio CT, and 50% with operative ultrasonography. Detection ratios of angio CT were superior to those of ultrasonography and CT. Recurrence rates of the remnant liver were significantly low and survival rates were significantly superior in the angio CT group compared to the other two groups (p<0.02). The prognosis with and without intermittent hepatic arterial infusion chemotherapy after hepatic resection were significantly different (p<0.03). The above data suggest that improvement of detection ratios for liver metastases by angio CT, and probably concomitant intermittent hepatic infusion chemotherapy contribute to decreased remnant liver recurrence and an increased survival rate. (author)

  3. Usefulness of unenhanced helical CT in patients with suspected ureteral colic

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bong Soo; Nam Kung, Sook; Kim, Heung Cheol; Hwang, Woo Chul; Lee, In Sun; Hwang, Im Kyung; Kim, Ho Chul; Bae, Sang Hoon; Lee, Sang Kon; Lee, Seong Ho [College of Medicine, Hallym Univ., Chunchon (Korea, Republic of)

    2002-07-01

    To determine the usefulness of unenhanced helical CT in patients with suspected renal colic. One hundred and fourteen patients with suspected ureteral colic, referred by physicians, underwent unenhanced helical CT. Two radiologists prospectively interpreted the results, determining the presence or absence of ureter stone and other diseases the arise outside the urinary tract. In cases of ureteral stone, we retrospectively sought secondary signs of hydronephrosis, perinephric fat stranding, thickening of renal fascia, renal enlargement, and the tissue rim sign. Among the 114 patients, 57 were confirmed as having ureter stones. Unenhanced helical CT depicted 57 of 58 stones in 57 patients, producing one false-negative and one false-positive result. Overall, the results showed 98% sensitivity, 95% specificity, 98% positive predictive value, 95% negative predictive value, and 97% accuracy. The frequencies of secondary signs were as follows: hydronephrosis, 95%(54/57); perinephric fat stranding, 81% (46/57); thickening of renal fascia, 77% (44/57); renal enlargement , 65%(37/57); and the tissure rim sign 72%(21/29). In 20 patients, the diagnoses were not related to stone disease and included one false-negative diagnosis of pyonephrosis. Unenhanced helical CT provides information which is valuable in the accurate diagnosis of ureteral stone as well as other diseases that arise outside the urinary tract in patients with suspected renal colic.

  4. Non-contrast thin-section helical CT of urinary tract calculi in children

    International Nuclear Information System (INIS)

    Strouse, Peter J.; Bates, Gregory D.; Bloom, David A.; Goodsitt, Mitchell M.

    2002-01-01

    Background: Non-contrast thin-section helical CT has gained acceptance for the diagnosis of urinary tract calculi in adults, but experience with the technique in children is limited. Purpose: To evaluate the utility of non-contrast thin section helical CT for the diagnosis of urinary tract calculi in children. Materials and methods: Radiology databases at three pediatric institutions were searched to identify all pediatric patients evaluated by ''renal stone'' protocol CT scans (no oral or intravenous contrast, scans covering the entire urinary tract obtained in helical mode with narrow collimation (< 5 mm)). CT scans were reviewed for the primary finding of urinary tract calculi, for secondary signs of acute urinary tract obstruction and for evidence of alternative diagnoses. Medical records were reviewed to determine clinical presentation and to confirm the eventual diagnosis. Results: One hundred thirty-seven scans of 113 children (mean age: 11.2 years) were studied. Thirty-eight of 94 examinations (40%) performed on 82 children for acute pain and/or hematuria showed ureteral calculi. Alternative diagnoses were suggested by CT on 16 scans (17%). Twenty-eight scans were performed on 10 asymptomatic children with known calculus disease confirming renal stone burden on 21 scans (75%) and persistent ureteral calculi on 6 scans (21%). Upper tract calculi were demonstrated on 10 of 15 scans (67%) performed to evaluate for calculi in patients with known non-calculus genitourinary tract abnormalities. Conclusions: Non-contrast thin section helical CT is a useful method to diagnose urinary tract calculi in children. Radiation dose in this retrospective study may exceed the lowest possible radiation dose for diagnostic accuracy. Further research is needed to optimize CT imaging parameters, while maintaining diagnostic accuracy and minimizing radiation dose. (orig.)

  5. Thin section helical CT findings of klastskin tumor and benign stricture: cholangiographic correlation

    International Nuclear Information System (INIS)

    Choi, Guk Myeong; Han, Joon Koo; Kim, Tae Kyoung; Choi, Byung Ihn; Kim, Sun Whe; Cho, Yun Ku; Han, Man Chung; Yeon, Kyung Mo

    1997-01-01

    The purpose of this study was 1) to describe the thin section helical CT findings of hilar cholangiocarcinoma and of benign strcture, and to discuss the differential points between the two disease entities and 2) using cholangiographic correlation, to evaluate the diagnostic accuracy of helical CT in determining the extent of hilar cholangiocarcinoma. Twenty-seven patients with hilar cholangiocarcinoma and eight with benign biliary dilatation were studied. All except four with hilar cholangiocarcinoma, who underwentCT using a conventional scanner, were studied with two-phase helical CT. In all patients, cholangiographs were obtained by digital fluoroscopy after the injection of contrast materials into PTBD catheters. The level of obstruction was classified according to Bismuth, and 35 CT scans were studied blindly and retrospectively by two radiologists. The findings were analyzed for the presence of tumor, and then divided into two groups(cholangiocarcinomas and benign strictures), and the positive predictive value was calculated. The CT images of klatskin tumor were analyzed with special emphasis on the level and shape of the hilar obstruction. The level of biliary obstruction and extent of the tumor were carefully correlated with the results of cholangiography. Thin-section spiral CT correctly identified all tumor mass as a focal wall thickening obliterating the lumen. On arterial/portal phase CT scanning, 81% of infilterative tumors showed high attenuation. In all patients, differentiation between benign stricture and klaskin tumor was possible;correct identification of the level of obstruction and extent of tumor, according to Bismuth's classification, was possible in 63% of cases. For correct diagnosis of hilar cholangiocarcinoma and differentiation of benign stricture, helical CT was highly accurate and effective. Because of limital Z-axis resolution, however, the exact intraductal extent of the tumor was less accorately diagnosed.=20

  6. Low dose coronary CT angiography with 256-slice helical CT

    International Nuclear Information System (INIS)

    Zhang Xiaodong; Tang Binghang; Li Fangyun

    2011-01-01

    of 573) in B, 96.1% (548 of 570) in C, and 85.7% (505/589) in D, with no significant difference for A vs C (Z= -1.351, P>0.05) and with significant differences for B vs D (Z=-2.236, P<0.05). Linear correlation analysis indicated a significant degradation of image quality with the increase of heart rate using SAS mode (Spearman correlation, r=0.577, P<0.01). ROC analysis established an upper HR threshold of 78 bpm for obtaining diagnostic image quality using SAS mode (AUC = 0.827, P<0.05). The average radiation dose in group A [(2.6±0.5) mSv] reduced 75% comparing with that in group C [(10.6±2.3) mSv], and the average radiation dose in group B [(4.0±0.7) mSv] reduced 69% comparing with that in group D [(13.0±1.4) mSv]. Conclusion: Using SAS mode to perform low-dose CCTA with 256-slice helical CT could keep the image quality and reduce radiation dose significantly. Our preliminary experience suggests a good promise of this technique which could be applied to a wider group of patients such as with higher heart rates. (authors)

  7. An experimental study for qualitatively diagnosing stapes lesions by helical 3-dimensional CT

    International Nuclear Information System (INIS)

    Kawaue, Akifumi; Kuki, Kiyonori; Yamanaka, Noboru; Nishimura, Michihiko

    2001-01-01

    To evaluate qualitative diagnosis of stapes lesions by 3-dimensional computed tomography (3D-CT) combined with superselective image processing (3D-SS) of stapes, we studied helical 3D-CT on a phantom model of the temporal bone. Two stapes models were used-1 made from the bone filler, Celatite, consistent in bone density but changing in cross sectional area, and the other made from an apacerum rod used in quantitative computed tomography (QCT), consistent in cross sectional area but changing in bone density. These stapes models were put into a skull phantom and analyzed by helical 3D-CT. The influence of the tympanic cavity conditions on CT images of stapes was evaluated by filling the phantom model with Vaseline following 3D selective reconstruction. In all stapes models, lowering the lower CT window width threshold resulted in an enlarged cross-sectional area of the model. The higher the bone density, the lower the increase in cross-sectional area in the image. The stapes model with lower density had greater influence on the imaging by tympanic cavity conditions and was likely to be misdiagnosed as showing higher bone density. Based on the experimental study, 3D-SS by helical 3D-CT appears to be a useful measure for qualitatively diagnosing stapes lesions. (author)

  8. A rigid motion correction method for helical computed tomography (CT)

    International Nuclear Information System (INIS)

    Kim, J-H; Kyme, A; Fulton, R; Nuyts, J; Kuncic, Z

    2015-01-01

    We propose a method to compensate for six degree-of-freedom rigid motion in helical CT of the head. The method is demonstrated in simulations and in helical scans performed on a 16-slice CT scanner. Scans of a Hoffman brain phantom were acquired while an optical motion tracking system recorded the motion of the bed and the phantom. Motion correction was performed by restoring projection consistency using data from the motion tracking system, and reconstructing with an iterative fully 3D algorithm. Motion correction accuracy was evaluated by comparing reconstructed images with a stationary reference scan. We also investigated the effects on accuracy of tracker sampling rate, measurement jitter, interpolation of tracker measurements, and the synchronization of motion data and CT projections. After optimization of these aspects, motion corrected images corresponded remarkably closely to images of the stationary phantom with correlation and similarity coefficients both above 0.9. We performed a simulation study using volunteer head motion and found similarly that our method is capable of compensating effectively for realistic human head movements. To the best of our knowledge, this is the first practical demonstration of generalized rigid motion correction in helical CT. Its clinical value, which we have yet to explore, may be significant. For example it could reduce the necessity for repeat scans and resource-intensive anesthetic and sedation procedures in patient groups prone to motion, such as young children. It is not only applicable to dedicated CT imaging, but also to hybrid PET/CT and SPECT/CT, where it could also ensure an accurate CT image for lesion localization and attenuation correction of the functional image data. (paper)

  9. Multiphasic helical CT of hepatocellular carcinoma. Evaluation after chemo embolization

    International Nuclear Information System (INIS)

    Catalano, O.; Esposito, M.; Sandomenico, F.; Siani, A.; Nunziata, A.

    2000-01-01

    The main purpose of this work is to report the personal experience with addition of contrast-enhanced multiphase helical CT to unenhanced CT (Lipiodol CT) in the evaluation of patients with hepatocellular carcinoma treated with chemoembolization and to analyze the present role of oily agent CT. It has been retrospectively reviewed the examinations of 42 consecutive patients submitted to globla chemoembolization over a 2-year period. CT was performed 18-30 days after the treatment. The Lipiodol CT study was carried out with volume acquisitions. It has been considered as nodules all well-defined areas with dense oily agent uptake; uptake itself was classified as: 0=absent, I=lower tha 10% of the tumor volume; II=lower than 50%, III=50%, IV=homogeneous. Contrast-enhanced helical CT was performed with the 2-phase technique in 28 patients and with the 3-phase technique in 14; it has been considered as nodules all well-defined and relatively homogeneous areas with hyperattenuation in the arterial phase and hypo-isoattenuation in the portal and/or delayed phase, or with hypo-isoattenuation in the arterial phase and in the portal and/or delayed phase. Lipiodol CT permitted to recognize 65 nodules (1-5/patient, mean 1.5), namely 15 grade I, 21 grade II, 20 grade III and 9 grade IV. Multiphase CT identified 6 additional nodules in 5 patients, 5 hypervascular and 1 hypovascular, and better assessed the correct morphology and volume of grade I nodules. Only 4 of 6 nodules missed on Lipiodol CT showed oily agent uptake after a new chemoembolization session. Moreover after retreatment, carried out in 6 of 9 patients with grade I uptake (11 nodules in all), it has been found persistence of the grade I pattern in 5 nodules, grade II in 5, and grade III in 1. Lipiodol CT may miss liver nodules and underestimate the volume of nodules with poor uptake. Though Lipiodol CT should still be considered slightly more sensitive than multiphase CT, in the general opinion this technique has

  10. Helical CT scan for emergent patients with cerebrovascular diseases

    International Nuclear Information System (INIS)

    Matsumoto, Masato; Sato, Naoki; Nakano, Masayuki; Watanabe, Youichi; Kodama, Namio

    1995-01-01

    We studied 44 emergent patients with cerebrovascular diseases (18 cases of subarachnoid hemorrhage, 15 of occlusive lesions, 7 of intracerebral hematoma and 4 of suspected subarachnoid hemorrhage) using helical CT scan. The helical CT scan was performed with contrast medium at a rate of 3 ml/sec with a delay of 20 sec, and was carried out before conventional angiography. The reconstruction time of 3D-CTA was within 10 min. We were able to obtain findings for the lesion on 3D-CTA before those on conventional angiography. The 3D-CTA yielded excellent images of the vascular structures and anatomical relationships of the aneurysm, its neck and parent artery, and surrounding arteries. However, it proved difficult to visualize vessels of less than 1 mm in diameter, especially the perforating arteries. In occlusive diseases, the degree of stenosis depended on the changes in CT number threshold: at present, evaluations of the lesions should be made by conventional angiography. 3D-CTA using helical CT scan can thus be applied for emergent patients with cerebrovascular diseases. Surgical simulation images of 3D-CTA were especially useful at the time of operation. (author)

  11. Helical CT scan for emergent patients with cerebrovascular diseases

    Energy Technology Data Exchange (ETDEWEB)

    Matsumoto, Masato; Sato, Naoki; Nakano, Masayuki; Watanabe, Youichi; Kodama, Namio [Fukushima Medical Coll. (Japan)

    1995-08-01

    We studied 44 emergent patients with cerebrovascular diseases (18 cases of subarachnoid hemorrhage, 15 of occlusive lesions, 7 of intracerebral hematoma and 4 of suspected subarachnoid hemorrhage) using helical CT scan. The helical CT scan was performed with contrast medium at a rate of 3 ml/sec with a delay of 20 sec, and was carried out before conventional angiography. The reconstruction time of 3D-CTA was within 10 min. We were able to obtain findings for the lesion on 3D-CTA before those on conventional angiography. The 3D-CTA yielded excellent images of the vascular structures and anatomical relationships of the aneurysm, its neck and parent artery, and surrounding arteries. However, it proved difficult to visualize vessels of less than 1 mm in diameter, especially the perforating arteries. In occlusive diseases, the degree of stenosis depended on the changes in CT number threshold: at present, evaluations of the lesions should be made by conventional angiography. 3D-CTA using helical CT scan can thus be applied for emergent patients with cerebrovascular diseases. Surgical simulation images of 3D-CTA were especially useful at the time of operation. (author).

  12. New reconstruction algorithm in helical-volume CT

    International Nuclear Information System (INIS)

    Toki, Y.; Rifu, T.; Aradate, H.; Hirao, Y.; Ohyama, N.

    1990-01-01

    This paper reports on helical scanning that is an application of continuous scanning CT to acquire volume data in a short time for three-dimensional study. In a helical scan, the patient couch sustains movement during continuous-rotation scanning and then the acquired data is processed to synthesize a projection data set of vertical section by interpolation. But the synthesized section is not thin enough; also, the image may have artifacts caused by couch movement. A new reconstruction algorithm that helps resolve such problems has been developed and compared with the ordinary algorithm. The authors constructed a helical scan system based on TCT-900S, which can perform 1-second rotation continuously for 30 seconds. The authors measured section thickness using both algorithms on an AAPM phantom, and we also compared degree of artifacts on clinical data

  13. Spatial variation of the section sensitivity profile in helical CT

    International Nuclear Information System (INIS)

    Katsuta, Shoichi; Hanai, Kouzou; Kunii, Takeo; Kimura, Haruki; Imabayashi, Wataru; Muramatsu, Yoshihisa

    1999-01-01

    The section sensitivity profile (SSP) is adequate to express the properties of helical CT images. Although SSP measurement has been performed only at the center of the imaging field, we applied it to off-center positions using a metal bead and controlled tracking technique. The experimental results indicated that SSP curves vary in the imaging field according to the relative position of the x-ray focus. The results were in agreement with computer simulations. (author)

  14. New approach to lung cancer screening with helical volume CT

    International Nuclear Information System (INIS)

    Midorikawa, S.; Hashimoto, N.; Katakura, T.; Suzuki, K.

    1990-01-01

    This paper evaluates the relationship between reducing radiation dose to the patient and maintaining the clinical quality of the chest image in lung cancer screening by helical-volume CT (HVCT). The authors evaluated the changing relationship between radiation dose and clinical quality after changing the HVCY scanning conditions (such as stroke of patient transport and section thickness) as well as adding copper filters of various thickness and using high-voltage x-ray examination to complement CT examinations. The authors were able to reduce radiation dose by changing the HVCT scanning conditions (eg, stroke of 20 mm/sec, with a section thickness of 10 mm)

  15. Solitary Pulmonary Nodule on Helical Dynamic CT Scans: Analysis of the Enhancement Patterns Using a Computer-Aided Diagnosis (CAD) System

    International Nuclear Information System (INIS)

    Choi, Eun Jung; Jin, Gong Yong; Han, Young Min; Lee, Young Sun; Kweon, Keun Sang

    2008-01-01

    We wanted to investigate the usefulness of a computer-aided diagnosis (CAD) system in assisting radiologists to diagnosis malignant solitary pulmonary nodules (SPNs), as compared with diagnosing SPNs with using direct personal drawing. Forty patients with SPNs were analyzed. After the pre-contrast scan was performed, an additional ten series of post-contrast images were obtained at 20-second intervals. Two investigators measured the attenuation values of the SPNs: a radiologist who drew the regions of interest (ROIs), and a technician who used a CAD system. The Bland and Altman plots were used to compare the net enhancement between a CAD system and direct personal drawing. The diagnostic characteristics of the malignant SPNs were calculated by considering the CAD and direct personal drawing and with using Fisher's exact test. On the Bland and Altman plot, the net enhancement difference between the CAD system and direct personal drawing was not significant (within ± 2 standard deriation). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of diagnosing malignant SPNs using CAD was 92%, 85%, 75%, 96% and 88%, respectively. The sensitivity, specificity, PPV, NPV and accuracy of diagnosing malignant SPNs using direct drawing was 92%, 89%, 79%, 92% and 88%, respectively. The CAD system was a useful tool for diagnosing malignant SPNs

  16. Emergencies in the retroperitoneum: assessment of spread of disease by helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Scialpi, M. E-mail: michelescialpi@libero.it; Scaglione, M.; Angelelli, G.; Lupattelli, L.; Resta, M.C.; Resta, M.; Rotondo, A

    2004-04-01

    Acute pancreatitis, leaking abdominal aortic aneurysm, and renal trauma frequently occur in the setting of patients with abdominal nontraumatic and traumatic injury; it represents the most urgent conditions that may determine the presence of fluid collections or haematoma in the retroperitoneum. Single spiral CT and multidetector-row CT (MDCT) play an important role in diagnosis of retroperitoneal emergencies, providing useful informations on the type, site, extent and management of the fluid collections. An accurate CT assessment requires the awareness of the existence of dissectable retroperitoneal fascial planes. Fluid collections or haematoma tends to escape the retroperitoneal site of origin into planes extend from the diaphragm to the pelvic floor. We assess the multicompartimental anatomy of the retroperitoneum and the pathway of spread of the most frequent retroperitoneal fluid collections or haematoma by helical CT.

  17. The effect of pitch in multislice spiral/helical CT

    International Nuclear Information System (INIS)

    Wang, G.; Vannier, M.W.

    2000-01-01

    The purpose of this study is to understand the effect of pitch on raw data interpolation in multislice spiral/helical computed tomography (CT) and provide guidelines for scanner design and protocol optimization. Multislice spiral CT is mainly characterized by the three parameters: the number of detector arrays, the detector collimation, and the table increment per x-ray source rotation. The pitch in multislice spiral CT is defined as the ratio of the table increment over the detector collimation in this study. In parallel to the current framework for studying longitudinal image resolution, the central fan-beam rays of direct and opposite directions are considered, assuming a narrow cone-beam angle. Generally speaking, sampling in the Radon domain by the direct and opposite central rays is nonuniform along the longitudinal axis. Using a recently developed methodology for quantifying the sensibility of signal reconstruction from non-uniformly sampled finite points, the effect of pitch on raw data interpolation is analyzed in multislice spiral CT. Unlike single-slice spiral CT, in which image quality decreases monotonically as the pitch increases, the sensibility of raw data interpolation in multislice spiral CT increases, suggesting that image quality does not decrease monotonically in this case. The most favorable pitch can be found from the sensitivity-slice spiral CT is provided. The study on the effect of pitch using the sensitivity analysis approach reveals the fundamental characteristics of raw data interpolation in multislice spiral CT, and gives insights into interaction between pitch and image quality. These results may be valuable for design of multislice spiral CT scanners and imaging protocol optimization in clinical applications. (authors)

  18. Clinical application of the helical CT in patients who are unable to hold their breath

    International Nuclear Information System (INIS)

    Toyama, Yoshihiro; Kimura, Naruhide; Ohkawa, Motoomi; Tanabe, Masatada.

    1997-01-01

    We performed helical CT in eighteen patients who were unable to hold their breath for 10 chest and 8 abdominal regions. Although there were respiratory artifacts in three cases, we could obtain the useful clinical information in all cases. In our experimental examinations, CT value of the phantom by helical scan was lower than that by conventional scan without movement of the phantom. With movement of it, the CT value was further lowered by either scan method, but the lowered rate was smaller by helical scan as the movement becomes faster. We consider that helical CT can be applied to patients who were unable to hold their breath. (author)

  19. Preliminary study on helical CT algorithms for patient motion estimation and compensation

    International Nuclear Information System (INIS)

    Wang, G.; Vannier, M.W.

    1995-01-01

    Helical computed tomography (helical/spiral CT) has replaced conventional CT in many clinical applications. In current helical CT, a patient is assumed to be rigid and motionless during scanning and planar projection sets are produced from raw data via longitudinal interpolation. However, rigid patient motion is a problem in some cases (such as in the skull base and temporal bone imaging). Motion artifacts thus generated in reconstructed images can prevent accurate diagnosis. Modeling a uniform translational movement, the authors address how patient motion is ascertained and how it may be compensated. First, mismatch between adjacent fan-beam projections of the same orientation is determined via classical correlation, which is approximately proportional to the patient displacement projected onto an axis orthogonal to the central ray of the involved fan-beam. Then, the patient motion vector (the patient displacement per gantry rotation) is estimated from its projections using a least-square-root method. To suppress motion artifacts, adaptive interpolation algorithms are developed that synthesize full-scan and half-scan planar projection data sets, respectively. In the adaptive scheme, the interpolation is performed along inclined paths dependent upon the patient motion vector. The simulation results show that the patient motion vector can be accurately and reliably estimated using their correlation and least-square-root algorithm, patient motion artifacts can be effectively suppressed via adaptive interpolation, and adaptive half-scan interpolation is advantageous compared with its full-scale counterpart in terms of high contrast image resolution

  20. Bronchial carcinoid tumor: helical CT and virtual bronchoscopy

    International Nuclear Information System (INIS)

    Diez, Eduardo; Carrascosa, Patricia; Capunay, Carlos; Spinozzi, German; Abramson, Horacio; Berna, Miguel

    2001-01-01

    The authors reported a case of a 61 years old man with recurrent neumonia of the inferior right lobe diagnosed by a chest radiography. A complementary helical CT showed an endobronquial mass on the right intermediate bronchus. Virtual bronchoscopy contributed to a better definition of this lesion, confirmed by a real bronchoscopy. The lesion was diagnosed as a carcinoid tumor by a bronchial biopsy. After surgery (sleeve resection of the tumor) the patient did not show any recurrence of his broncho-neumonic clinical features. (author)

  1. CT diagnosis of rectal cancer

    International Nuclear Information System (INIS)

    Kanda, Hiroshi; Hachisuka, Kitao; Yamaguchi, Akihiro

    1986-01-01

    Preoperative diagnosis of the depth of invasion and lymph node metastasis of rectal cancer were studied using the findings of computed tomography (CT). Of one hundred and four cases operated on for rectal cancer over a period of 32 months, thirty five cases were examined by CT with the use of olive oil enema and contrast enhancement using a 60 % Conray drip infusion with reference to the histological findings. For direct invasion into the wall, the diagnoses by CT were coincident with microscopic findings in 75 % of cancers of the rectosigmoid, in 75 % of the upper rectum and in 84 % of the lower rectum. Of all cases, 28 (80 %) were diagnosed correctly. As to local lymph node metastasis, 74 % of all diagnoses by CT corresponded with the histological diagnosis. Moreover, seventeen cases were evaluated for lateral lymph node metastasis, and the diagnostic accuracy by CT was 88 %. In conclusion, preoperative CT evaluation of the extension into the rectal wall and lymph node metastasis in rectal cancer was considesed useful. (author)

  2. 3D CT versus axial helical CT versus conventional tomography in the classification of acetabular fractures: A ROC analysis

    International Nuclear Information System (INIS)

    Kickuth, Ralph; Laufer, Ulf; Hartung, Guido; Gruening, Christian; Stueckle, Christoph; Kirchner, Johannes

    2002-01-01

    AIM: To assess the diagnostic power of three-dimensional computed tomography (3D CT), axial helical computed tomography (CT) and conventional tomography in the classification of acetabular fractures by interdisciplinary review. MATERIALS AND METHODS: Receiver operating characteristics (ROCs) were assessed for two radiologists and two surgeons blinded to the presence of acetabular fractures in an animal model (a total of 62 porcine hips, 40 of them with artificial acetabular fractures). Main target parameter was the diagnostic accuracy in the classification of the artificial fractures following Judet et al. RESULTS: ROC analysis for radiologists showed A z values of 0·83 for 3D CT, 0·81 for axial helical CT, and 0·78 for conventional tomography; differences between the three techniques were not significant (P = 0·46-0·73). A z values for the surgeons were 0·87 for 3D CT, 0·68 for axial helical CT, and 0·60 for conventional tomography; 3D CT was significantly better than axial helical CT (P = 0·01) and conventional tomography (P = 0·001). The differences between axial helical CT and conventional tomography were not significant (P = 0·37). CONCLUSION: Acetabular fractures are best classified by 3D CT, followed by axial helical CT and conventional tomography when assessed by surgeons. 3D CT did not provide any additional significant benefit in the classification performed by radiologists. Kickuth, R. et al. (2002)

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

    International Nuclear Information System (INIS)

    Sumikawa, Hiromitsu; Johkoh, Takeshi; Koyama, Mitsuhiro

    2005-01-01

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

  4. Computer-aided diagnosis workstation and network system for chest diagnosis based on multislice CT images

    Science.gov (United States)

    Satoh, Hitoshi; Niki, Noboru; Eguchi, Kenji; Moriyama, Noriyuki; Ohmatsu, Hironobu; Masuda, Hideo; Machida, Suguru

    2008-03-01

    Mass screening based on multi-helical CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. To overcome this problem, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images, a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification and a vertebra body analysis algorithm for quantitative evaluation of osteoporosis likelihood by using helical CT scanner for the lung cancer mass screening. The function to observe suspicious shadow in detail are provided in computer-aided diagnosis workstation with these screening algorithms. We also have developed the telemedicine network by using Web medical image conference system with the security improvement of images transmission, Biometric fingerprint authentication system and Biometric face authentication system. Biometric face authentication used on site of telemedicine makes "Encryption of file" and Success in login" effective. As a result, patients' private information is protected. Based on these diagnostic assistance methods, we have developed a new computer-aided workstation and a new telemedicine network that can display suspected lesions three-dimensionally in a short time. The results of this study indicate that our radiological information system without film by using computer-aided diagnosis workstation and our telemedicine network system can increase diagnostic speed, diagnostic accuracy and security improvement of medical information.

  5. Determination of optimal parameters for three-dimensional reconstruction images of central airways using helical CT

    International Nuclear Information System (INIS)

    Hirose, Takahumi; Akata, Soichi; Matsuno, Naoto; Nagao, Takeshi; Abe, Kimihiko

    2002-01-01

    Three-dimensional (3D) image reconstruction of central airways using helical CT requires several user-defined parameters that exceed the requirements of conventional CT. The purpose of this study was to evaluate the optimal parameters for 3D images of central airways using helical CT. In our experimental study using a piglet immediately after sacrifice, 3D images of the central airway were evaluated with changes of 3D imaging parameters, such as detector collimation (1, 2, 3 and 6 mm), table speed (1, 2, 3 and 5 mm/sec), tube electric current (50, 100, 150, 200 and 250 mA), reconstruction interval (0.3, 0.5, 1, 2 and 3 mm), algorithm (mediastinum and lung) and interpolation method (180 deg and 360 deg). To minimize detector collimation, table speed, and reconstruction interval could provide the best 3D images of the central airway. Stair-step artifacts could also be reduced with a slow table speed. However, decreasing the collimation and table speed decreases not only the effective section thickness but also the scan coverage that can be achieved with a helical CT. For routine diagnosis, we conclude that optimal parameters for 3D images of the central airway are to minimize the table speed necessary to cover the volume of interest and to set detector collimation to 1/2 of the table speed. The reconstruction intervals should also be selected at up to 1/2 of the detector collimation, but with trade-offs of increased image processing time, data storage requirements, and physician time for image review. Regarding to tube electric current, 200 mA or more was necessary. Pixel noise increased with the algorithm for the lung. The 180 deg interpolation is better than 360 deg interpolation due to thin effective section thickness. (author)

  6. Metastatic tumor of the pancreas: helical CT findings

    International Nuclear Information System (INIS)

    Lee, Soon Jin; Lee, Won Jae; Lim, Hyo Keun; Kim, Seung Hoon; Kim, Kyeong Ah; Choi, Sang Hee; Jang, Hyun Jung; Lee, Ji Yeon

    2000-01-01

    To analyze the helical computed tomographic (CT) findings of distant metastatic tumors to the pancreas and to determine the differential points between these and primary pamcreatic carcinomas. We sruveyed 22 patients with metastatic tumor of the pancreas, proven on the basis of clinical and pathological findings. Seventeen patients were men, and five were women, and their ages ranged between 36 and 83 years. Their primary conditions were lung cancer (n=3D15), rectal cancer (n=3D2), melanoma of the foot, chondrosarcoma of the sacrum, cervical cancer, leiomyosarcoma of the uterus, and extragonadal choriocarcinoma of the mediastinum. We retrospectively reviewed the abdominal helical CT findings, analysing the number, location, size and attenuation of masses, as well as secondary change, which included dilatation of the pancreatic and biliary ducts and invasion of peripancreatic tissue or vessels. We also evaluated the differential findings of primary pancreatic cancer. Sixteen patients had a solitary focal mass, while in five, two masses were present. Among the 22 patients, low-density nodular masses were present in 21; in the other, in whom multiple metastasis from chondrosarcoma had occurred, there was dense calcification. The size of metastatic masses varied, ranging from 0.6 to 6 cm in diameter. The pancreatic duct proximal to the mass was dilated in ten cases, while the bile duct was dilated in six. The metastatic masses masses demonstrated no peripancreatic or vascular invasion, though they showed a discrete margin and contour bulging. Single metastasis to the pancreas was most common, and metastatic masses had a discrete margin, with contour bulging. There was no peripancreatic or vascular invasion. If the metastasis involved a single low-attenuated mass, however, with pancreatic or biliary dilatation, it was difficult to differentiate this from primary pancreatic cancer. (author)

  7. Helical CT finding of carotid-cavernous fistula: a sign of early enhancing superior ophthalmic vein

    International Nuclear Information System (INIS)

    Kim, Jae Hyung; Na, Dong Gyu; Byun, Hong Sik; Ryoo, Jae Wook

    2000-01-01

    The purpose of this study was to determine the diagnostic value of a sign of early enhancing superior ophthalmic vein (SOV), as seen on helical CT images in patients with carotid-cavernous fistula (CCF). This study involved 16 patients with CCF and 28 control patients. Axial CT images with scanning delays of 30 seconds following bolus injection of contrast material (90 mL, 3 mL/sec) were obtained, and this procedure was followed by coronal CT imaging. To determine the presence or absence of early enhancement or, dilatation of the SOV, bulging of the cavernous sinus, and enlargement of extraocular muscle, CT images were analysed by three observers in a blinded, random manner. Early enhancement of SOV was determined to be present where enhancement of the SOV was similar to or stronger than that of the ipsilateral posterior cerebral artery. A sign of early enhancing SOV was seen in 14 of the 16 patients with CCF but in no control patients (88% sensitivity and 100% specificity). The respective sensitivity and specificity of other CT features were 71% and 100% (dilatation of the SOV, as seen on axial images), 60% and 83% (dilatation of the SOV, as seen on coronal images), 71% and 89% (dilatation of the cavernous sinus), and 65% and 98% (enlargement of extraocular muscle). A sign of early enhancing SOV is a characteristic and specific CT finding of CCF, and is useful for the diagnosis of CCF. (author)

  8. Dynamic multislice helical CT of maxillomandibular lesions. Distinction of ameloblastomas from other cystic lesions

    Energy Technology Data Exchange (ETDEWEB)

    Tozaki, Mitsuhiro; Hayashi, Katsuhiko; Fukuda, Kunihiko [Jikei Univ., Tokyo (Japan). School of Medicine

    2001-10-01

    The purpose of this study was to evaluate the clinical usefulness of dynamic multislice helical CT in differentiating ameloblastoma from other cystic lesions in cases of maxillomandibular cystic lesions. The study included 32 patients with maxillomandibular cystic lesions (ameloblastoma [n=6], myxofibroma [n=1], odontogenic keratocyst [n=3], dentigerous cyst [n=11], radicular cyst [n=11], and paradental cyst [n=2]). Dynamic study was performed before and 30 sec, and 90 sec after intravenous contrast medium administration. CT density values and percentage of density increase were calculated at 30 and 90 sec. In five cases of ameloblastoma, a rapidly enhancing area was detected within the cystic lesions at 30 sec, while no apparent rapid enhancement was seen in the other cystic lesions. Three cysts showed gradual enhancement in the marginal area at 90 sec. Comparing ameloblastoma and other kinds of cysts, we found significant differences in the percentage of density increase at 30 sec (p<0.01) and 90 sec (p<0.05). Dynamic multislice helical CT is useful in the diagnosis of cystic lesions of the maxillomandibular region, especially in the detection of neovascularities in ameloblastoma. (author)

  9. Dynamic multislice helical CT of maxillomandibular lesions. Distinction of ameloblastomas from other cystic lesions

    International Nuclear Information System (INIS)

    Tozaki, Mitsuhiro; Hayashi, Katsuhiko; Fukuda, Kunihiko

    2001-01-01

    The purpose of this study was to evaluate the clinical usefulness of dynamic multislice helical CT in differentiating ameloblastoma from other cystic lesions in cases of maxillomandibular cystic lesions. The study included 32 patients with maxillomandibular cystic lesions (ameloblastoma [n=6], myxofibroma [n=1], odontogenic keratocyst [n=3], dentigerous cyst [n=11], radicular cyst [n=11], and paradental cyst [n=2]). Dynamic study was performed before and 30 sec, and 90 sec after intravenous contrast medium administration. CT density values and percentage of density increase were calculated at 30 and 90 sec. In five cases of ameloblastoma, a rapidly enhancing area was detected within the cystic lesions at 30 sec, while no apparent rapid enhancement was seen in the other cystic lesions. Three cysts showed gradual enhancement in the marginal area at 90 sec. Comparing ameloblastoma and other kinds of cysts, we found significant differences in the percentage of density increase at 30 sec (p<0.01) and 90 sec (p<0.05). Dynamic multislice helical CT is useful in the diagnosis of cystic lesions of the maxillomandibular region, especially in the detection of neovascularities in ameloblastoma. (author)

  10. Virtual endoscopy post-processing of helical CT data sets

    International Nuclear Information System (INIS)

    Dessl, A.; Giacomuzzi, S.M.; Springer, P.; Stoeger, A.; Pototschnig, C.; Voelklein, C.; Schreder, S.G.; Jaschke, W.

    1997-01-01

    Purpose: The purpose of this work was to test a newly developed, post-processing software for virtual CT endoscopic methods. Virtual endoscopic images were generated from helical CT data sets in the region of the shoulder joint (n=2), the tracheobronchial system (n=3), the nasal sinuses (n=2), the colon (n=2), and the common carotid artery (n=1). Software developed specifically for virtual endoscopy ('Navigator') was used which, after a previous threshold value selection, makes the reconstruction of internal body surfaces possible by an automatic segmentation process. We have evaluated the usage of the software, the reconstruction time for individual images and sequences of images as well as the quality of the reconstruction. All pathological findings of the virtual endoscopy were confirmed by surgery. Results: The post-processing program is easy to use and provides virtual endoscopic images within 50 seconds. Depending of the extent of the data set, virtual tracheobronchoscopy as a cine loop sequence required about 15 minutes. Thorugh use of the threshold value-dependent surface reconstruction the demands on the computer configuration are limited; however, this also created quality problems in image calculation as a consequence of the accompanying loss of data. Conclusions: The Navigator software enables the calculation of virtual endoscopic models with only moderate demands on the hardware. (orig.) [de

  11. Early clinical phase of patient's management after polytrauma using 1- and 4-slice helical CT

    International Nuclear Information System (INIS)

    Kloeppel, R.; Kahn, T.; Schreiter, D.; Dietrich, J.; Josten, C.

    2002-01-01

    In the early clinical phase the comprehensive imaging of patients with multiple trauma using helical CT is already established. Aim of this study was to assess whether MSCT may improve the patient management and the diagnostic results.The procedure is designed as follows: after life-thretening treatment x-ray of chest and ultrasound are carried out in the emergency room. Then the patient is moved to CT. From 1998 to december 2000 241 patients were examined using a single slice helical CT (Somatom plus 4), in 2001 79 patients using a 4-slice helical CT (Somatom VZ, Siemens Med.Sol.). After CT selected radiograms of the extremities were taken.359 of 360 procedures were carried out successfully. Excluding 1 case (death during 1-sl. h CT) all relevant lesions of head, neck, and body were diagnosed. Although the patients had an injury severity score of ∼30. The change from 1slice-helical CT to 4 slice-helical CT allowed us to reduce the stay in the CT room from 28 to 16 min. The total lethality decreased by ∼4%.Advantages for the patient arose from the standardized examination protocol using multislice CT. If integrated in an interdisciplinary management concept, it is a good compromise between examination time, comprehensive diagnostic imaging, life-saving therapeutic procedures, and therapy planning. (orig.) [de

  12. Prospective comparison of helical CT with angiography in pulmonary embolism: global and selective vascular territory analysis. Interobserver agreement

    International Nuclear Information System (INIS)

    Ruiz, Yolanda; Caballero, Paloma; Caniego, Jose Luis; Friera, Alfonsa; Olivera, Maria Jose; Tagarro, David; Alvarez-Sala, Rodolfo

    2003-01-01

    The objective of this prospective study was to evaluate the sensitivity, specificity, positive and negative predictive values, and interobserver agreement in the diagnosis of pulmonary embolism with helical CT, compared with pulmonary angiography, for both global results and for selective vascular territories. Helical CT and pulmonary angiography were performed on 66 consecutive patients with clinical suspicion of pulmonary embolism. The exams were blindly interpreted by a vascular radiologist and by two independent thoracic radiologists. Results were analyzed for the final diagnosis as well as separately for 20 different arterial territories in each patient. Pulmonary angiography revealed embolism in 25 patients (38%); 48% were main, 28% lobar, 16% segmental, and 8% subsegmental. The sensitivity, specificity, and positive and negative predictive values of helical CT for observer 1 were, respectively, 91, 81.5, 75, and 94%; in 7.5% of the patients the exam was considered indeterminate. For observer 2 the values were, respectively, 88, 86, 81.5, and 91%; in 9% of the patients the exam was considered indeterminate. Main arteries were considered as non-valuable in 0-0.8%, the lobar in 1.5%, the segmental in 7.5-8.5%, and the subsegmental in 55-60%. Interobserver agreement for the final diagnosis was 80% (kappa 0.65). For each vascular territory, this was 98% (kappa 0.91) for main arteries, 92% (kappa 0.78) for lobar arteries, 79% (kappa 0.56) for segmental arteries, and 59% (kappa 0.21) for subsegmental arteries. Helical CT is a reliable method for pulmonary embolism diagnosis, with good interobserver agreement for main, lobar, and segmental territories. Worse results are found for subsegmental arteries, with high incidence of non-valuable branches and poor interobserver agreement. (orig.)

  13. CT diagnosis of thyroid carcinoma

    International Nuclear Information System (INIS)

    Luo Dehong; Shi Mulan; Luo Douqiang

    1998-01-01

    Purpose: To study the CT appearances of thyroid carcinoma and its cervical metastatic lymphadenopathy, as well as to evaluate the diagnostic criteria of tumor invasion of adjacent structures. Methods: CT findings of surgery and pathology proved thyroid carcinoma in 52 patients were analyzed. Results: All of the primary tumor were heterogeneous in density, 32 tumors (82.5%) were ill-defined. Fine granular calcifications were revealed in 11 primary tumors and metastatic lymph nodes in 5 cases. Cystic formation with intracystic high density papillary-like nodules were found in 4 primary tumors and metastatic lymphadenopathy in 5 cases. Trachea, esophagus and carotic artery invasion were proved by surgery in 22, 21 and 10 cases respectively. Serrated inner wall and tumor nodule protrusion into tracheal lumen were the definite signs of trachea invasion. Use tumor encasement over 1/2 of the circumference of esophagus and 1/3 of the circumference of carotid artery as the diagnostic criterion of invasion, sensitivity was 71.4%, 100.0% specificity was 96.3%, 95.2% respectively. Conclusion: Fine granular calcification and cystic formation with high attenuation intracystic papillary-like nodules were characteristic manifestations of primary thyroid carcinoma (especially papillary carcinoma) and its metastatic lymphadenopathy as well. Contrast enhanced CT scan is helpful in the diagnosis of thyroid carcinoma and the delineation of tumor extent, which is very important in surgical planning

  14. Diagnosis of gastric cancers by CT

    International Nuclear Information System (INIS)

    Zhu Jianbing; Gong Jianping; Huan Jian

    1999-01-01

    Forty two cases of gastric cancers were reviewed. The cancer had been examined by CT and was confirmed by operation and pathology. The diagnostic results of gastric cancers obtained by CT were compared with that from GI and fibro-gastroscopy examination. The results showed that the preparation of gastrointestinal tract before CT examination was important in the CT diagnosis of gastric cancer. CT in diagnosis of focus of gastric cancer and organ invasion is better than Gl and Fibro-gastroscopy and accuracy in diagnosis of gastric cancers is near to that of GI examination

  15. Analysis of aliasing artifacts in 16-slice helical CT

    International Nuclear Information System (INIS)

    Chen Wei; Liu Jingkang; Ou Xiaoguang; Li Wenzheng; Liao Weihua; Yan Ang

    2006-01-01

    Objective: To recognize the features of aliasing artifacts on CT images, and to investigate the effects of imaging parameters on the magnitude of this artifacts. Methods: An adult dry skull was placed in a plastic water-filled container and scanned with a PHILIPS 16-slice helical CT. All the acquired transaxial images by using several different acquisition or reconstruction parameters were examined for comparative assessment of the aliasing artifacts. Results: The aliasing artifacts could be seen in most instances and characterized as the spokewise patterns emanating from the edges of high contrast structure as its radius varies sharply in the longitudinal direction. The images that scanned with pitch of 0.3, 0.6 and 0.9, respectively, showed aliasing artifacts, and its severities increased with pitches escalated (detector combination 16 x 1.5, reconstruction thickness 2 mm); There were more significant aliasing artifacts on the images reconstructed with 0.8 mm slice width compared with 1-mm slice width, and no aliasing artifacts were observed on the images reconstructed with 2-mm slice width (detector combination 16 x 0.75, pitch 0.6); No artifacts were perceived on the images scanned with detector combination 16 x 0.75, while presented evidently with the use of detector combination 16 x 1.5 (pitch 0.6, reconstruction thickness 2 mm); The degrees of aliasing artifacts were unaltered when reconstruction interval and tube current changed. Conclusions: Aliasing artifacts are caused by undersampling. When the operator choose the thinner sampling thickness, lower pitch and a much wider reconstruction thickness judiciously, aliasing artifacts could be effectively mitigated or suppressed. (authors)

  16. The evaluation of gallbladder contractibility for volume measurement by helical 3D-CT-cholangiography

    International Nuclear Information System (INIS)

    Hanaguri, Katsuro; Kimura, Hideaki; Kayashima, Yasuyo; Suemoto, Kouichiro; Makihata, Hiroshi; Maruhashi, Akira; Ohya, Toshihide; Ito, Katsuhide; Shen, Yun.

    1997-01-01

    As a new application of helical (spiral) scan, volume measurement has received a significant interest. Although it is important to evaluate gallbladder contractibility to decide on a treatment plan for a gallbladder lesion, qualitative analysis of gallbladder contractibility is very difficult owing to the fact that the volume of gallbladder can not be measured using usual DIC examination (plain X-P and tomography). In this study, the accuracy of volume measurement of helical CT was checked firstly by gallbladder phantom experiments. Then 128 cases of volume measurement of helical 3D CT Cholangiography (DIC-CT) were performed. Under the conditions of optimized scan technique (3 mm TH, 3 mm/s, 1 mm recon interval, Hispeed, GEMS), the difference of contractibility was obtained between clinical cases with and without thick wall. The experiment has shown that helical 3D CT volume measurement is very simple and highly accurate method which is useful for the evaluation of gallbladder contractibility. (author)

  17. CT diagnosis in diseases of the breast

    International Nuclear Information System (INIS)

    Han Hongbin; Xie Jingxia

    1998-01-01

    Purpose: To study the CT signs of breast diseases, and discuss the value of CT in the diagnosis of breast cancer and the axillary lymph node (LN) metastases. Materials and methods: Fifty three cases were reported, including breast cancer 30 cases and benign diseases 23 cases. CT were performed in all patients, 44 also had mammography examination. Results: (1) The CT appearance of breast cancer: round or irregular mass, spiculate border, duct retraction, involved Cooper's ligament, deformed adipose space etc. Benign hyperplasia: Irregular mass and symmetrical thickening of breast glands. Cystic hyperplasia: typically multiple, round, liquid-density mass. (2) CT was comparable to mammography in terms of differential diagnosis, however with breast mass located near the axilla or for evaluation of the thoracic wall. CT was superior to mammography. CT was also helpful in detecting LN metastases. Conclusion: CT is valuable in detecting and differentiating breast diseases as well as in the diagnosis of LN metastases

  18. Three-dimensional helical CT for treatment planning of breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Hiramatsu, Hideko; Enomoto, Kohji; Ikeda, Tadashi [Keio Univ., Tokyo (Japan). School of Medicine] [and others

    1999-01-01

    The role of three-dimensional (3D) helical CT in the treatment planning of breast cancer was evaluated. Of 36 patients examined, 30 had invasive ductal carcinoma, three had invasive lobular carcinoma, one had DCIS, one had DCIS with minimal invasion, and 1 had Paget`s disease. Patients were examined in the supine position. The whole breast was scanned under about 25 seconds of breath-holding using helical CT (Proceed, Yokogawa Medical Systems, or High-speed Advantage, GE Medical Systems). 3D imaging was obtained with computer assistance (Advantage Windows, GE Medical Systems). Linear and/or spotty enhancement on helical CT was considered to suggest DCIS or intraductal spread in the area surrounding the invasive cancer. Of 36 patients, 24 showed linear and/or spotty enhancement on helical CT, and 22 of those 24 patients had DCIS or intraductal spread. In contrast, 12 of 36 patients were considered to have little or no intraductal spread on helical CT, and eight of the 12 patients had little or no intraductal spread on pathological examination. The sensitivity, specificity, and accuracy rates for detecting intraductal spread on MRI were 85%, 80%, and 83%, respectively. 3D helical CT was considered useful in detecting intraductal spread and planning surgery, however, a larger study using a precise correlation with pathology is necessary. (author)

  19. Helical CT in the primary trauma evaluation of the cervical spine: an evidence-based approach

    Energy Technology Data Exchange (ETDEWEB)

    Blackmore, C.C. [Washington Univ., Seattle, WA (United States). Dept. of Radiology; Center for Cost and Outcomes Research, Univ. of Washington, Seattle (United States); Dept. of Radiology, Harborview Medical Center, Seattle, WA (United States); Mann, F.A. [Washington Univ., Seattle, WA (United States). Dept. of Radiology; Harborview Injury Prevention and Research Center, University of Washington, Seattle (United States); Wilson, A.J. [Washington Univ., Seattle, WA (United States). Dept. of Radiology

    2000-11-01

    This review provides a summary of the cost-effectiveness, clinical utility, performance, and interpretation of screening helical cervical spine CT for trauma patients. Recent evidence supports the use of helical CT as a cost-effective method for screening the cervical spine in high-risk trauma patients. Screening cervical spine CT can be performed at the time of head CT to lower the cost of the evaluation, and when all short- and long-term costs are considered, CT may actually save money when compared with traditional radiographic screening. In addition to having higher sensitivity and specificity for cervical spine injury, CT screening also allows more rapid radiological clearance of the cervical spine than radiography. Patients who are involved in high-energy trauma, who sustain head injury, or who have neurological deficits are candidates for CT screening. Screening with CT may enhance detection of other potentially important injuries of the cervical region. (orig.)

  20. Role of contrast-enhanced helical CT in the evaluation of acute thoracic aortic injuries after blunt chest trauma

    International Nuclear Information System (INIS)

    Scaglione, M.; Pinto, A.; Pinto, F.; Romano, L.; Ragozzino, A.; Grassi, R.

    2001-01-01

    The purpose of this retrospective study was to determine the value of contrast-enhanced helical CT for detecting and managing acute thoracic aortic injury (ATAI). Between June 1995 and February 2000, 1419 consecutive chest CT examinations were performed in the setting of major blunt trauma. The following CT findings were considered indicative of ATAI: intimal flap; pseudoaneurysm; contour irregularity; lumen abnormality; and extravasation of contrast material. On the basis of these direct findings no further diagnostic investigations were performed. Isolated mediastinal hematoma on CT scans was considered an indirect sign of ATAI: In these cases, thoracic aortography was performed even if CT indicated normal aorta. Seventy-seven patients had abnormal CT scans: Among the 23 patients with direct CT signs, acute thoracic aortic injuries was confirmed at thoracotomy in 21. Two false-positive cases were observed. The 54 remaining patients had isolated mediastinal hematoma without aortic injuries at CT and corresponding negative angiograms. The 1342 patients with negative CT scans were included in the 8-month follow-up program and did not show any adverse sequela based on clinical and radiographic criteria. Contrast-enhanced helical CT has a critical role in the exclusion of thoracic aortic injuries in patient with major blunt chest trauma and prevents unnecessary thoracic aortography. Direct CT signs of ATAI do not require further diagnostic investigations to confirm the diagnosis: Isolated aortic bands or contour vessel abnormalities should be first considered as possible artifacts or related to non-traumatic etiologies especially when mediastinal hematoma is absent. In cases of isolated mediastinal hematoma other possible sources of bleeding should be considered before directing patients to thoracic aortography. (orig.)

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

    International Nuclear Information System (INIS)

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

    1998-01-01

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

  2. Incidental diagnosis of diseases on un-enhanced helical computed tomography performed for ureteric colic

    Directory of Open Access Journals (Sweden)

    Ather M Hammad

    2003-03-01

    Full Text Available Abstract Background Patients presenting in the emergency room with flank pain suggestive of acute ureteric colic may have alternative underlying conditions mimicking ureteric stones. An early diagnosis and appropriate treatment for other causes of flank pain is important. The majority of centers around the world are increasingly using un-enhanced helical CT (UHCT for evaluation of ureteric colic. This study was conducted to determine the incidence and spectrum of significant incidental diagnoses established or suggested on UHCT performed for suspected renal/ureteric colic. Methods Urologist and radiologist reviewed 233 consecutive UHCT, performed for suspected renal/ureteral colic along with assessment of the medical records. Radiological diagnoses of clinical entities not suspected otherwise were analyzed. All other relevant radiological, biochemical and serological investigations and per-operative findings were also noted. Results Ureteral calculi were identified in 148 examinations (64%, findings of recent passage of calculi in 10 (4% and no calculus in 75 examinations (32%. Overall the incidental findings (additional or alternative diagnosis were found in 28 (12% CT scans. Twenty (71% of these diagnoses were confirmed by per-operative findings, biopsy, and other radiological and biochemical investigations or on clinical follow up. Conclusion A wide spectrum of significant incidental diagnoses can be identified on UHCT performed for suspected renal/ureteral colic. In the present series of 233 consecutive CT examinations, the incidence of incidental diagnosis was 12%.

  3. Diagnostic value of triphasic incremental helical CT in early and progressive gastric carcinoma

    International Nuclear Information System (INIS)

    Gao Jianbo; Yan Xuehua; Li Mengtai; Guo Hua; Chen Xuejun; Guan Sheng; Zhang Xiefu; Li Shuxin; Yang Xiaopeng

    2001-01-01

    Objective: To investigate helical CT enhancement characteristics of gastric carcinoma, and the diagnostic value and preoperative staging of gastric carcinoma with triphasic incremental helical CT of the stomach with water-filling method. Methods: Both double-contrast barium examination and triphasic incremental helical CT of the stomach with water-filling method were performed in 46 patients with gastric carcinoma. Results: (1) Among these patients, normal gastric wall exhibited one layered structure in 18 patients, two or three layered structure in 28 patients in the arterial and portal venous phase. (2) Two cases of early stomach cancer showed marked enhancement in the arterial and portal venous phase and obvious attenuation of enhancement in the equilibrium phase. On the contrary, 32 of the 44 advanced gastric carcinoma was showed marked enhancement in the venous phase compared with the arterial phase ( t = 4.226, P < 0.05). (3) The total accuracy of triphasic incremental helical CT in determining TNM-staging was 81.0%. Conclusion: Different types of gastric carcinoma have different enhancement features. Triphases incremental helical CT is more accurate than conventional CT in the preoperative staging of gastric carcinoma

  4. CT diagnosis of occipital bone pacchionian depression

    International Nuclear Information System (INIS)

    Zhu Jianguo; Xu Xiaolin

    2004-01-01

    Objective: To improve the recognition of the CT findings of occipital bone pacchionian depression, in order to avoid misdiagnosis. Methods: occipital bone pacchionian depression underwent CT with plain scan and intravenous contrast enhancement in 11 cases, and then the CT findings were analyzed. Results: Occipital bone pacchionian depression situated beside the torcular herophilia in 11 cases. The depression or bone defect were found at occipital bone inner plate, they can reach diploe or outer plate and had no enhancement after contrast injection. Conclusions: CT scans play an important role in diagnosis and differential diagnosis of occipital bone pacchionian depression

  5. The evaluation study of helical CT for hepatocellular carcinoma with microwave coagulation treatment

    International Nuclear Information System (INIS)

    Zheng Keguo; Xu Dasheng; Xie Xiaoyan; Peng Zhenpeng

    2002-01-01

    Objective: To study the helical CT signs of the hepatocellular carcinoma (HCC) after percutaneous microwave coagulation therapy (PMCT) and to evaluate the correlation between the helical CT signs and the therapeutic effect of HCC. Methods: The helical CT signs were analyzed in 22 cases with 26 lesions of the hepatocellular carcinoma that were treated with PMCT under ultrasonic guidance. Results: In 21 lesions, no enhancement was detected in the lesion border or inside the lesion at hepatic arterial phase (HAP) and portal venous phase (PVP). In 7 lesions, the slight or marked patchy enhancement was revealed in the surrounding liver of the lesions in HAP. In 5 lesions, nodular enhancement was found in the lesion border or inside the lesion in HAP. Conclusion: The dual-phase helical CT might be accurate in judging the therapeutic effect of HCC after PMCT. If no enhancement was showed in the lesions in the dual-phase helical CT, it indicated that no tumor survived. If slight or marked patchy pattern enhancement was revealed in the surrounding liver of the lesions in HAP, it was a normal reaction after PMCT. If nodular enhancement was found in the lesion border or inside the lesion in HAP, it indicated that the tumor partially survived

  6. Pitch dependence of longitudinal sampling and aliasing effects in multi-slice helical computed tomography (CT)

    International Nuclear Information System (INIS)

    La Riviere, Patrick J.; Pan Xiaochuan

    2002-01-01

    In this work, we investigate longitudinal sampling and aliasing effects in multi-slice helical CT. We demonstrate that longitudinal aliasing can be a significant, complicated, and potentially detrimental effect in multi-slice helical CT reconstructions. Multi-slice helical CT scans are generally undersampled longitudinally for all pitches of clinical interest, and the resulting aliasing effects are spatially variant. As in the single-slice case, aliasing is shown to be negligible at the isocentre for circularly symmetric objects due to a fortuitous aliasing cancellation phenomenon. However, away from the isocentre, aliasing effects can be significant, spatially variant, and highly pitch dependent. This implies that measures more sophisticated than isocentre slice sensitivity profiles are needed to characterize longitudinal properties of multi-slice helical CT systems. Such measures are particularly important in assessing the question of whether there are preferred pitches in helical CT. Previous analyses have generally focused only on isocentre sampling patterns, and our more global analysis leads to somewhat different conclusions than have been reached before, suggesting that pitches 3, 4, 5, and 6 are favourable, and that half-integer pitches are somewhat suboptimal. (author)

  7. CT diagnosis of cystic ovarian lesions

    International Nuclear Information System (INIS)

    Iio, Kazuto; Shinmura, Ryoji; Arima, Naomi; Yamada, Eiichiro; Ohkubo, Koichi; Nagata, Yukihiro

    1985-01-01

    CT was undertaken and CT numbers were measured in 47 patients with cystic ovarian lesions. CT features particularly for chocolate cyst revealed the uniform thickness of the whole cystic wall, findings suggesting adhesion to the surrounding organs, circular or oval shape, and higher CT numbers within the cyst than those in the other cystic ovarian lesions. However, because these features are not always observed in cases of chocolate cyst, one should not rely solely on CT findings in the diagnosis of chocolate cyst. (Namekawa, K.)

  8. Identification of the segmental artery feeding the anterior spinal artery. Correlation between helical CT and angiography

    International Nuclear Information System (INIS)

    Nishimura, Jun-ichi; Lee, Jin; Koike, Shigeomi

    2005-01-01

    We investigated whether identification of the segmental artery feeding the anterior spinal artery (ASA) is possible by single-slice helical CT. Enhanced CT and angiography were performed in 14 patients with retroperitoneal, liver, or bone tumor. A single-slice helical CT scanner with 7 mm collimation and a 1.0 helical pitch was used. Scanning was started 25 to 30 sec after an intravenous injection of 100 ml of contrast medium at a rate of 3.0 ml/sec. We predicted the segmental artery feeding the ASA in all 14 patients using enhanced CT images. In 12 of the 14 patients, the segmental artery feeding the ASA was angiographically identified. In 7 of these 12 patients, the level of the segmental artery feeding the ASA identified on segmental arteriogram was the same level as that predicted by enhanced CT. In the remaining 5 patients, the level of the segmental artery feeding the ASA identified on segmental arteriogram was one level higher or lower than the predicted spinal level. We could identify the segmental artery feeding the ASA by detailed examination and interpretation of single-slice helical CT images. (author)

  9. Low-dosage helical CT applications for chest medical checkup and lung cancer screening

    International Nuclear Information System (INIS)

    Wang Ping; Cui Fa; Liang Huanqing; Zheng Minfei

    2005-01-01

    Objective: A discussion on low-dosage helical CT applications on chest medical checkup and lung cancer screening. Methods: On the 100 chest medical check up with three different of protocols, including standard-dosage (the tube current was 230 mAs) were compared with low-dose (tube current was 50 mAs or 30 mAs). Results: Low-dosage helical CT scan provides excellent images. In 100 chest medical checkup, 39 nodules or masses were revealed, enlarged lymph node was noted in 1 case; emphysema or bullae was demonstrated in 3 segments; thickening of bronchial wall was shown in 2 cases; and localized pleural thickening was found in 1 case. Conclusion: In chest checkup or lung cancer screening low-dosage helical CT (tube current 30 mAs) will not only guarantee image quality but also reduce the radiation dose during the examination. (authors)

  10. CT diagnosis and differential diagnosis of malignant pleural mesothelioma

    International Nuclear Information System (INIS)

    Xiong Juxin; Yang Zenian; Luo Zhongyao

    2008-01-01

    Objective: To study the CT features of malignant pleural mesothelioma and improve diagnostic accuracy. Methods: The CT findings of 14 patients with malignant pleural mesothelioma proven by surgery or histopathology were analyzed retrospectively. CT plain scan was performed in all cases, 9 cases received both CT plain scan and contrast CT scan. Results: All the cases demonstrated various pleural thickening including diffuse pleural thickening (n=10). Among all the cases, there were nodular pleural thickening (n=4), lumpy pleural thickening (n=7), ring-like pleural thickening (n=3). Pleural thickness which was more than 1.0 cm was found in 12 cases. Pleural effusion (n=10), mediastinum immobilization (n=10) and thoracic cavity stricture in the trouble side (n=10) were also revealed. Conclusion: Obvious characteristics in cases with malignant pleural mesothelioma was showed in CT examination, which plays an important role in the diagnosis and differential diagnosis of this disease. (authors)

  11. The utility of helical CT in assessing the frequency of ureterolithiasis in Saudi patients

    International Nuclear Information System (INIS)

    Al-Nakshabandi, Nizar A.; Zayed, Mohamed A.; Elsharkaway, Mohamed S.; Al-Boukai, Ahmad S.; Al-Omar, M.

    2008-01-01

    Objective was to identify 650 patients who underwent Ct for renal colic and review them for age and gender in Saudi Arabia. Scans were performed on a 16 multislice scanner. A total of 650 patients with the clinical suspicion of ureteric colic were reviewed; 220 females (33.8%) and 430 males (66.2%), with a female to male ratio of 1:2. Examinations were carried out from January 2005 to November 2006, at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia. Three hundred and ninety five patients out of 650 had stones; 2 of 395 (0.5%) had stones in the 5-15 years age group, 28 (7.%) in the 16-25 years age group, 99 (25.1%) in the 26-35 years, 106 (26.8%) in the 36-45 age group, 84 (21.9%) in the 46-55 age group, 51 (12.9%) in the 56-65 age group, and 25 (6.3%) in the above 66 years age group. The most significant finding in our study is that as the patients age increases so does the percentage of stones up to the age of 56, with a peak at age group of 26-35 where stone percentage reaches 26.8%. Unenhanced helical CT is useful for the diagnosis of ureterolithiasis. (author)

  12. Pancreatic adenocarcinoma: dual-phase helical CT with surgical and histopathologic correlation

    International Nuclear Information System (INIS)

    Kim, Eun A; Yoon, Kwon Ha; Park, Seong Hoon; Yun, Ki Jung; Won, Jong Jin

    2003-01-01

    To determine the accuracy of dual-phase helical CT in assessing the resectability of pancreatic ductal adenocarcinoma, and to correlate the CT findings with the surgical and histopathologic findings. Thirty patients with pathologically proven cancer of the pancreas underwent arterial-and portal-phase helical CT scanning, and in the two of these, single-level dynamic CT was performed during celiac and superior mesenteric arteriography. In 17 patients who underwent surgery for potentially resectable cancer of the pancreatic head, tumor resectability was assessed. The CT findings were analyzed and correlated with these of surgery and histopathology. In 13 (76%) of the 17 patients who underwent surgery, tumors were resectable. Their average size was 2.76 cm (arterial phase), 2.30 cm (portal phase), and 2.48 cm (pathologically determined) and the overall accuracy of helical CT for assessing resectability was 87%. In all patients, the central portion of the tumors exhibited hypoattenuation at both phases; the peripheral portion showed hypoattenuation at the arterial phase and iso- (n=10) or hyperattenuation (n=3) at the portal phase. Single-level dynamic CT depicted a persistently hypoattenuating central portion and progressive and prolonged enhancement of the periphery. CT-histopathologic correlation showed that central hypoattenuation indicated the presence of tumor cells, necrosis (n=3) and mucin (n=4), while the peripheral iso- or hyperattenuated areas seen at the portal phase represented fibrosis and inflammatory infiltration. Histopathologic examination revealed tumoral infiltration of peripancreatic fat tissue (n=11) and microvascular invasion of major peripancreatic vessels (n=7). The dual-phase helical CT is useful in the determination of resectability in pancreas cancer and CT findings represent well the histopathologic features of pancreas cancer

  13. Pancreatic adenocarcinoma: dual-phase helical CT with surgical and histopathologic correlation

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun A; Yoon, Kwon Ha; Park, Seong Hoon; Yun, Ki Jung; Won, Jong Jin [Wonkwang University School of Medicine, Iksan (Korea, Republic of)

    2003-03-01

    To determine the accuracy of dual-phase helical CT in assessing the resectability of pancreatic ductal adenocarcinoma, and to correlate the CT findings with the surgical and histopathologic findings. Thirty patients with pathologically proven cancer of the pancreas underwent arterial-and portal-phase helical CT scanning, and in the two of these, single-level dynamic CT was performed during celiac and superior mesenteric arteriography. In 17 patients who underwent surgery for potentially resectable cancer of the pancreatic head, tumor resectability was assessed. The CT findings were analyzed and correlated with these of surgery and histopathology. In 13 (76%) of the 17 patients who underwent surgery, tumors were resectable. Their average size was 2.76 cm (arterial phase), 2.30 cm (portal phase), and 2.48 cm (pathologically determined) and the overall accuracy of helical CT for assessing resectability was 87%. In all patients, the central portion of the tumors exhibited hypoattenuation at both phases; the peripheral portion showed hypoattenuation at the arterial phase and iso- (n=10) or hyperattenuation (n=3) at the portal phase. Single-level dynamic CT depicted a persistently hypoattenuating central portion and progressive and prolonged enhancement of the periphery. CT-histopathologic correlation showed that central hypoattenuation indicated the presence of tumor cells, necrosis (n=3) and mucin (n=4), while the peripheral iso- or hyperattenuated areas seen at the portal phase represented fibrosis and inflammatory infiltration. Histopathologic examination revealed tumoral infiltration of peripancreatic fat tissue (n=11) and microvascular invasion of major peripancreatic vessels (n=7). The dual-phase helical CT is useful in the determination of resectability in pancreas cancer and CT findings represent well the histopathologic features of pancreas cancer.

  14. CT diagnosis of annular pancreas

    International Nuclear Information System (INIS)

    Ueno, Eiko; Isobe, Yoshinori; Niimi, Akiko; Shimizu, Yasushi; Yamada, Akiyoshi; Hanyu, Fujio

    1987-01-01

    CT scan was performed in two cases of annular pancreas which could be found in one case preoperatively and in the other case retrospectively. CT scan demonstrated secondary changes of annular pancreas such as medial displacement and dilatation of the duodenal bulb in the former case and stenosis of the duodenal loop and thickened soft tissue density around the narrow segment of the duodenal loop in the latter case, although it failed to demonstrate the peninsular protrusion of the parenchyma of the pancreas head. These findings suggest high possibility of diagnosing annular pancreas by CT scan. (author)

  15. Contrast-enhanced helical CT of the pancreas. Optimal timing of imaging for pancreatic tumor evaluation

    International Nuclear Information System (INIS)

    Koide, Kazuki; Sekiguchi, Ryuzo

    2001-01-01

    We performed three-phase helical CT in patients suspected pancreatic tumors and investigated the optimal timing of imaging for evaluation of the pancreatic mass. The pancreatic-phase was superior in detecting pancreatic tumors, including islet cell tumors that may show strong enhancement. However, portal vein-phase imaging was also superior in 16.7% of our patients. Taking into account examination for hepatic metastasis, helical CT of any pancreatic tumor should include images obtained in the pancreatic and portal vein phases. (author)

  16. Partial volume and aliasing artefacts in helical cone-beam CT

    International Nuclear Information System (INIS)

    Zou Yu; Sidky, Emil Y; Pan, Xiaochuan

    2004-01-01

    A generalization of the quasi-exact algorithms of Kudo et al (2000 IEEE Trans. Med. Imaging 19 902-21) is developed that allows for data acquisition in a 'practical' frame for clinical diagnostic helical, cone-beam computed tomography (CT). The algorithm is investigated using data that model nonlinear partial volume averaging. This investigation leads to an understanding of aliasing artefacts in helical, cone-beam CT image reconstruction. An ad hoc scheme is proposed to mitigate artefacts due to the nonlinear partial volume and aliasing artefacts

  17. Concept and development of measurement method of time sensitivity profile (TSP) in X-ray CT. Comparison of non-helical, single-slice helical, and multi-slice helical scans

    International Nuclear Information System (INIS)

    Tsujioka, Katsumi; Ida, Yoshihiro; Ohtsubo, Hironori; Takahashi, Yasukata; Niwa, Masayoshi

    2000-01-01

    We focused on the time element contained in a single CT image, and devised the concept of a time-sensitivity profile (TSP) describing how the time element is translated into an image. We calculated the data collection time range when the helical pitch is changed in non helical scans, single slice helical scans, and multi slice helical scans. We then calculated the time sensitivity profile (TSP) from the weighting applied when the data collection time range is translated into an image. TSP was also measured for each scanning method using our self-made moving phantom. TSPs obtained from the calculation and the experiments were very close. TSP showed interesting characteristics with each scanning method, especially in the case of multi slice helical scanning, in which TSP became shorter as helical pitch increased. We referred to the TSP's FWHM as the effective scanning time. When we conducted multi slice helical scanning at helical pitch 3, the effective scanning time increased to about 24% longer than that of a non helical scan. When we conducted multi slice helical scanning at helical pitch 5 or 6, the effective scanning time was about half that of a non helical scan. The time sensitivity profile (TSP) is a totally new concept that we consider an important element in discussing the time resolution of a CT scanner. The results of this review will provide significant data in determining the scanning parameters when scanning a moving object. (author)

  18. Three-dimensional CT endoscopic images of the larynx. Clinical application of helical CT

    International Nuclear Information System (INIS)

    Yumoto, Eiji; Sanuki, Tetsuji; Yasuhara, Yoshifumi; Ochi, Takashi

    1998-01-01

    Twenty-seven patients with several laryngeal ailments underwent helical computed tomography (CT) on 37 occasions. Ten of these 27 patients suffered from unilateral vocal fold paralysis (UVFP). Three-dimensional (3D) images of the laryngeal lumen viewed from various angles were produced for all sets of CT volumetric data, except for three which contained excessive motion artifacts. The present paper examined whether 3D endoscopic images could offer useful diagnostic and therapeutic information about UVFP. The 3D endoscopic images viewed from the tracheal side and the hemilaryngeal images viewed from the opposite side could delineate the vocal folds, ventricular fold and ventricle three-dimensionally. Atrophy and hypotonic changes to the vocal fold and expansion of the ventricle on the affected side were clearly shown. The 3D endoscopic images accurately showed the phonosurgical effects on the laryngeal structures. The 3D endoscopic images could be produced even when the vocal folds could not be observed with conventional endoscopy due to their overadduction. Multiplanar reconstruction (MPR) images in the coronal plane were reconstructed at a right angle to the glottic axis when the whole larynx was deviated. In addition, coronal MPR images showed a better resolution among the different layers of the vocal fold soft tissue than X-ray tomography. In conclusion, 3D endoscopic images combined with coronal MPR images can provide useful diagnostic an therapeutic information about UVFP, although motion artifacts may occur. (author)

  19. CT diagnosis of ruptured abdominal aortic aneurysm

    International Nuclear Information System (INIS)

    Sacknoff, R.; Novelline, R.A.; Wittenberg, J.; Waltman, A.C.; De Luca, S.A.; Rhea, J.T.; Lawrason, J.N.

    1986-01-01

    Ruptured abdominal aortic aneurysm (AAA) is a life-threatening condition requiring immediate diagnosis and surgery. In a series of 23 consecutive patients scanned by CT for suspected ruptured AAA, CT proved 100% accurate. In seven patients with surgically or pathologically proved ruptured AAA, CT demonstrated a similar distribution of hemorrhage into the perirenal space and to a lesser degree into the anterior and posterior pararenal spaces. The 16 true-negative examinations included ten in patients with unruptured AAA and six in patients with other diseases. The authors conclude that patients in stable condition with suspected ruptured AAA should be examined by CT

  20. CT diagnosis of peritoneal metastasis tumor

    International Nuclear Information System (INIS)

    Deng Xueying; Chen Xiaoqi; Qi Le; Huang Feng

    2005-01-01

    Objective: To study the CT findings and diagnosis of peritoneal metastasis. Methods: The CT findings of 17 cases with surgical- pathologically proved peritoneal metastasis were analyzed retrospectively. Results The CT findings of peritoneal metastasis included: (1)ascites (12 cases ); (2)the aternation of parietal peritoneum including broad band thickening (7 cases), nodular sign (2 cases), and massive thickening (1 cases); (3) the involved omentum and mesenterium: 'smut' appearances (7 cases), nodular sign (2 cases), 'omental cake' (5 cases); (4) the invlovement of mesenteric vessels; (5) single-or multi-cystic lesions within peritoneum (1 case) . Conclusion: CT scan is the first choice for metastasis of peritoneum. (authors)

  1. Lung scintigraphy and helical computed tomography for the diagnosis of pulmonary embolism : A meta-analysis

    NARCIS (Netherlands)

    van Beek, EJR; Brouwers, Elise M J; Song, B; Bongaerts, AHH; Oudkerk, M

    To assess the diagnostic value of lung scintigraphy and helical computed tomography (hCT) in patients with suspected pulmonary embolism (PE), all English-language articles that described lung scintigraphy and hCT in patients with suspected PE were retrieved. Articles were assessed for strength of

  2. Comparison of helical computed tomography and ultrasonography in diagnosis of acute appendicitis

    International Nuclear Information System (INIS)

    Nafees, M.; Abbas, G.; Sarwar, S.

    2010-01-01

    The objective of study is to compare the diagnostic accuracy of helical computed tomography and ultrasonography in acute appendicitis using histopathology as gold standard. Thirty cases of clinically suspected acute appendicitis were included in the study selected on non probability convenience sampling technique. Computed tomography and graded compression ultrasonography of right lower quadrant of abdomen were conducted and results compared with histopathological findings. Amongst 30 patients who underwent computed tomography and graded compression ultrasonography examinations of right lower quadrant for diagnosis of acute appendicitis, on computed tomography 19 were diagnosed with acute appendicitis, 10 were diagnosed as not having the disease and 01 patient diagnosed as not having appendicitis on computed tomography did not improve clinically, was operated upon and histopathology proved it as acute appendicitis. While on graded compression ultrasonography 15 were diagnosed with acute appendicitis, 11 were diagnosed as not having the disease and 04 patients diagnosed as not having appendicitis on ultrasonography, did not improve clinically, were operated upon and histopathology proved it as acute appendicitis. This showed that CT scan has sensitivity of 95%, specificity 100%, positive predictive value 100%, negative predictive value 90.91% and overall accuracy of 96.67% while ultrasonography has sensitivity of 78.9%, specificity 100%, positive predictive value 100%, negative predictive value 73.33% and overall accuracy of 86.67%. We concluded that Helical computed tomography is highly accurate in diagnosing acute appendicitis as compared to ultrasonography and it helps to reduce negative appendectomy rate. (author)

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

    International Nuclear Information System (INIS)

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

    1995-01-01

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

  4. Adenocarcinoma of the pancreatic head: preoperative helical CT. Criteria of resectability

    International Nuclear Information System (INIS)

    Kozima, Shigeru; Szelagowski, Carlos; Tisserand, Guy L.; Ocampo, Carlos; Zandalazini, Hugo; Silva, Walter; Oria, Alejandro; Vidovic, Gustavo; Varas, Pablo

    2001-01-01

    Objective: The purpose of this study is to determine the accuracy of biphasic helical CT scanning in predicting resectability of adenocarcinoma of the head of the pancreas by staying tumor involvement of the portal and superior mesenteric veins. Material and methods: 46 patients with proven adenocarcinoma of the head of the pancreas who underwent curative or palliative surgery were studied with preoperative biphasic helical CT scanning. Tumor involvement of the portal and mesenteric veins was graduated on a 1-3 scale based on circumferential contiguity of the tumor vessel. Grade 1: without contact; grade 2: tumor involvement of less than 50% of the vessel; grade 3: tumor involvement of more than 50%. Results: The total number of vessels evaluated was 92. In our series the preoperative biphasic helical CT was accurate in 77% for resectability and unresectability. Conclusion: Our experience of staging in 3 grades with biphasic helical CT, vessel involvement the portal and superior mesenteric veins of adenocarcinoma of the head of the pancreas is highly specific for unresectable tumor in patients who were graded 2 and 3. (author)

  5. Current status of multi-detector row helical CT in imaging of adult ...

    African Journals Online (AJOL)

    Current status of multi-detector row helical CT in imaging of adult acquired pancreatic diseases and assessing surgical neoplastic resectability. ... The presence of inflammation, masses, and vascular invasion was evaluated and interpreted images were obtained during each phase. Results were compared with surgery, ...

  6. Comparison of radiation dose estimates, image noise, and scan duration in pediatric body imaging for volumetric and helical modes on 320-detector CT and helical mode on 64-detector CT

    International Nuclear Information System (INIS)

    Johnston, Jennifer H.; Podberesky, Daniel J.; Larson, David B.; Alsip, Christopher; Yoshizumi, Terry T.; Angel, Erin; Barelli, Alessandra; Toncheva, Greta; Egelhoff, John C.; Anderson-Evans, Colin; Nguyen, Giao B.; Frush, Donald P.; Salisbury, Shelia R.

    2013-01-01

    Advanced multidetector CT systems facilitate volumetric image acquisition, which offers theoretic dose savings over helical acquisition with shorter scan times. Compare effective dose (ED), scan duration and image noise using 320- and 64-detector CT scanners in various acquisition modes for clinical chest, abdomen and pelvis protocols. ED and scan durations were determined for 64-detector helical, 160-detector helical and volume modes under chest, abdomen and pelvis protocols on 320-detector CT with adaptive collimation and 64-detector helical mode on 64-detector CT without adaptive collimation in a phantom representing a 5-year-old child. Noise was measured as standard deviation of Hounsfield units. Compared to 64-detector helical CT, all acquisition modes on 320-detector CT resulted in lower ED and scan durations. Dose savings were greater for chest (27-46%) than abdomen/pelvis (18-28%) and chest/abdomen/pelvis imaging (8-14%). Noise was similar across scanning modes, although some protocols on 320-detector CT produced slightly higher noise. Dose savings can be achieved for chest, abdomen/pelvis and chest/abdomen/pelvis examinations on 320-detector CT compared to helical acquisition on 64-detector CT, with shorter scan durations. Although noise differences between some modes reached statistical significance, this is of doubtful diagnostic significance and will be studied further in a clinical setting. (orig.)

  7. CT diagnosis of cystic echinococcosis in pelvis

    International Nuclear Information System (INIS)

    Liu Wenya; Li Li; Xing Yan; Xie Jingxia

    2003-01-01

    Objective: To analyze the CT findings of pelvic cystic echinococcosis, and to assess the value of CT examination. Methods: Twenty-one cases of pelvic cystic echinococcosis, confirmed by clinical and pathological results, underwent CT scanning. CT characters were analyzed and compared with pathology. Results: Simple cystic echinococcosis appeared as single or multiple cystic lesions with round or oval shape, smooth boundary, and no enhancement after contrast medium administration in 3 cases; Different number and size of daughter cysts were detected inside the lesion in 17 cases; Ruptured lesions showed 'double wall', 'water snake', or 'flow ribbon' signs in 4 cases; Increase density of contents and enhanced cystic wall were demonstrated in 2 cases with companied infections. In 8 cases, calcification occurred on the cystic wall or extended inside the content. Conclusion: CT could accurately demonstrate the location, appearance, internal structure, and adjacent situation of the cystic echinococcosis, providing valuable information for correct diagnosis and treatment

  8. Single-slice rebinning method for helical cone-beam CT

    International Nuclear Information System (INIS)

    Noo, F.; Defrise, M.; Clackdoyle, R.

    1999-01-01

    In this paper, we present reconstruction results from helical cone-beam CT data, obtained using a simple and fast algorithm, which we call the CB-SSRB algorithm. This algorithm combines the single-slice rebinning method of PET imaging with the weighting schemes of spiral CT algorithms. The reconstruction is approximate but can be performed using 2D multislice fan-beam filtered backprojection. The quality of the results is surprisingly good, and far exceeds what one might expect, even when the pitch of the helix is large. In particular, with this algorithm comparable quality is obtained using helical cone-beam data with a normalized pitch of 10 to that obtained using standard spiral CT reconstruction with a normalized pitch of 2. (author)

  9. Prenatal diagnosis of sirenomelia in the late second trimester with three-dimensional helical computed tomography.

    Science.gov (United States)

    Ono, Tetsuo; Katsura, Daisuke; Tsuji, Shunichiro; Yomo, Hiroko; Ishiko, Akiko; Inoue, Takashi; Kita, Nobuyuki; Takahashi, Kentaro; Murakami, Takashi

    2011-10-01

    Sirenomelia is a rare congenital syndrome that is characterized by the anomalous development of the caudal region of the body. The anomalies include bilateral renal agenesis or dysgenesis and the absence of the sacrum and other vertebral defects. Sirenomelia is also known as "mermaid syndrome," because of the one lower extremity. It is usually associated with severe oligohydramnios, and its prognosis is very poor due to pulmonary hypoplasia that is caused by severe oligohydramnios. The patient referred to our hospital at the gestational age of 27 weeks with fetal growth restriction and oligohydramnios. The estimated fetal body weight was 970 g (-4.9 S.D.). We could identify only one-side extremities, and could not identify kidneys by ultrasound examination. Because a single lower extremity and severe oligohydramnios are characteristics of the sirenomelia, we suspected sirenomelia. However, it could not be confirmed by ultrasound examination because of oligohydramnios. Therefore, we performed three-dimensional helical computed tomography (3D-CT), which is more accurate than ultrasound examinations for prenatal diagnosis of skeletal abnormalities. 3D-CT revealed an only one lower extremity. At 36 weeks and 5 days of gestation, the woman went into spontaneous labor and delivered an infant weighing 870 g. The infant has a single upper extremity and a single lower extremity. We provided supportive care for the neonate, who however died 1 hour 36 minutes after birth from severe respiratory distress. In summary, we report the correct diagnosis of sirenomelia with 3D-CT in the late second trimester.

  10. Chronic intestinal pseudo-obstruction in adult patients: multidetector row helical CT features

    International Nuclear Information System (INIS)

    Merlin, Aurelie; Soyer, Philippe; Boudiaf, Mourad; Hamzi, Lounis; Rymer, Roland

    2008-01-01

    Chronic intestinal pseudo-obstruction (CIPO) is a rare condition due to severe gastrointestinal motility disorder. Adult patients with CIPO experience symptoms of mechanical obstruction, but reliable clinical signs that may help distinguish between actual mechanical obstruction and CIPO are lacking. Additionally, abdominal plain films that commonly show bowel dilatation with air-fluid levels do not reach acceptable degrees of specificity to exclude actual obstruction. Therefore, most adult patients with CIPO usually undergo multiple and often fruitless surgery, often leading to repeated bowel resections before diagnosis is made. In these patients who present with abdominal signs mimicking symptoms that would warrant surgical exploration, multidetector-row helical CT (MDCT) is helpful to resolve this diagnostic dilemma. MDCT shows a diffusely distended bowel and helps to rule out a mechanical cause of obstruction, thus suggesting CIPO and obviating the need for unnecessary laparotomy. In adult patients with CIPO, MDCT may show pneumatosis intestinalis, pneumoperitoneum or intussusception. However, these conditions generally do not require surgery in patients with CIPO. This pictorial essay presents the more and less common MDCT features of CIPO in adult patients, to make the reader more familiar with this disease. (orig.)

  11. CT and ERCP diagnosis of obstructive jaundice

    International Nuclear Information System (INIS)

    Wang Dongfang; Cao Ran

    2003-01-01

    Objective: To evaluate some specific CT and ERCP findings for differentiating the nature of biliary obstructive diseases. Methods: In total 85 cases of obstructive jaundice verified by pathology were selected. The CT findings in 45 cases and ERCP features in 68 cases were retrospectively analyzed. Results: Mild dilatation of intrahepatic bile ducts were usually found in benign diseases, while moderately or severely dilated intrahepatic bile ducts were revealed in malignancies. Dilatation of intrahepatic bile ducts in vine pattern was one of the characteristic signs of malignant lesions, while 'withered branches' dilatation was usually found in benign diseases. Dilated extra-hepatic bile duct abruptly narrowed or obstructed was a typical finding in malignancies, while gradual tapering of common bile duct at the obstructed level usually indicated benign nature of the disease. Conclusion: Both CT and ERCP are valuable modalities in locating and differential diagnosis of biliary obstruction. A combined evaluation improves the accuracy of diagnosis

  12. Optimization of pediatric examinations in a multislice helical CT

    International Nuclear Information System (INIS)

    Ombada, T. H. A.

    2010-12-01

    Radiological protection of pediatric patients undergoing medical imaging procedures involving ionizing radiation has always received special attention. This is due to the fact that children have higher radiation sensitivity and increased likelihood for radiation-induced cancer manifesting in many more years of their life than adults. In computed tomography (CT), such attention is more important because of the potential of relatively higher radiation doses during these procedures. Such high doses are possible with technological developments where volume scanning using faster multi-slice CT systems is now preferred to conventional CT equipment. The task of this study is to assess the optimization of paediatric doses in multi-slice CT examinations. It was carried out in Alrebat University Hospital for 31 pediatric patients, 43 examinations (27 head examination and 16 body (chest, abdomen and pelvis) examinations). Data were collected for scan parameters (kV, m As, pitch, scan length, number of slices and slice thickness) and doses displayed in monitor (CTDI v ol and DLP) for head examinations and body (chest, abdomen and pelvis) examinations. For head CT, displayed CTDI v ol ranged from 1.56 to 69.12 mGy, calculated value from 2.10 to 70.93 mGy. Displayed DLP ranged from 53 to 1817 mGy.cm, calculated from 95.30 to 1532.16 mGy. cm. For body examination, the range of displayed CTDI from 1.63 to 3.92 mGy, calculated value from 2.22 to 5.34 mGy. Displayed DLP ranged from 34 to 194 mGy.cm, for calculated from 45.89 to 161.98 mGy. cm. The calculated values are in agreement with reference study dose values although there are some high values in this study for some examinations, this variation or difference may attribute to variation in pediatric ages (9 days- 15 years), scan length and m As values. There is variation between calculated and displayed values. more optimization for CT doses is needed. (Author)

  13. Optimization of pediatric examinations in a multislice helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Ombada, T H. A. [Atomic Energy Council, Sudan Academy of Sciences (SAS), Khartoum (Sudan)

    2010-12-15

    Radiological protection of pediatric patients undergoing medical imaging procedures involving ionizing radiation has always received special attention. This is due to the fact that children have higher radiation sensitivity and increased likelihood for radiation-induced cancer manifesting in many more years of their life than adults. In computed tomography (CT), such attention is more important because of the potential of relatively higher radiation doses during these procedures. Such high doses are possible with technological developments where volume scanning using faster multi-slice CT systems is now preferred to conventional CT equipment. The task of this study is to assess the optimization of paediatric doses in multi-slice CT examinations. It was carried out in Alrebat University Hospital for 31 pediatric patients, 43 examinations (27 head examination and 16 body (chest, abdomen and pelvis) examinations). Data were collected for scan parameters (kV, m As, pitch, scan length, number of slices and slice thickness) and doses displayed in monitor (CTDI{sub v}ol and DLP) for head examinations and body (chest, abdomen and pelvis) examinations. For head CT, displayed CTDI{sub v}ol ranged from 1.56 to 69.12 mGy, calculated value from 2.10 to 70.93 mGy. Displayed DLP ranged from 53 to 1817 mGy.cm, calculated from 95.30 to 1532.16 mGy. cm. For body examination, the range of displayed CTDI from 1.63 to 3.92 mGy, calculated value from 2.22 to 5.34 mGy. Displayed DLP ranged from 34 to 194 mGy.cm, for calculated from 45.89 to 161.98 mGy. cm. The calculated values are in agreement with reference study dose values although there are some high values in this study for some examinations, this variation or difference may attribute to variation in pediatric ages (9 days- 15 years), scan length and m As values. There is variation between calculated and displayed values. more optimization for CT doses is needed. (Author)

  14. CT diagnosis of abdominal abscess in children

    International Nuclear Information System (INIS)

    Li Xin; Yang Zhiyong

    1998-01-01

    Purpose: To evaluate CT in the diagnosis of abdominal abscess in children. Methods: Analysis of CT manifestations in 23 cases proved by operation and needle aspiration. Causes: acute appendicitis 13 cases, ascending colon perforation 1 case, Meckel diverticulitis 2 cases, cause obscured 7 cases. Bolus injection of contrast medium was given in 19 cases. Results: The CT value had no relationship to the course of disease and type of bacteria, amount of abscess had positive relevance relative with course of illness. Air-fluid level or scattered gas bubbles was seen in abscesses in 52%; little calcified plague was present in 22%. All cases presented nonhomogeneous thick wall enhancement after one week of illness. Conclusion: The characteristic CT features of intra-abdominal abscess were the presence of air and little calcified plague shadow; a large air-fluid level was indicative of fistula, while the absence of air in the abscess can not exclude fistula

  15. Helical CT appearance of hypovascular small hepatocellular carcinoma with pathologic correlation

    International Nuclear Information System (INIS)

    Zheng Keguo; Xu Dasheng; Shen Jingxian

    2003-01-01

    Objective: To study the helical CT dual-phase enhancement manifestation of the hypodense small hepatocellular carcinoma, and to evaluate its correlation with the histopathology. Methods: The CT signs and its histopathologic changes were analyzed in 25 cases with 27 hypodense lesions in helical CT dual-phase enhancement. All the lesions were confirmed as small hepatocellular carcinoma by operation and histopathology. Results: (1) On unenhanced scan, 16 lesions were with obscure borders and 11 lesions were with well-delineated borders. On enhanced scan, only 7 lesions were with obscure borders and the other 20 lesions were with well-delineated borders, and their contours were slightly irregular. (2) On unenhanced scan, 18 lesions showed homogeneous hypodensity and 9 lesions showed heterogeneous hypodensity. On enhanced scan, only 6 lesions showed homogeneous hypodensity and the other 21 lesions showed heterogeneous hypodensity with multiple flecks of more hypodense areas. Conclusion: The helical CT dual-phase enhancement characteristic manifestations of hypodense small hepatocellular carcinoma were as follows: the border of the lesion was obscure on unenhanced scan, however the border of the lesion became well-delineated and slightly irregular, and there were multiple flecks of more hypodense areas in the lesions after enhancement. This might be an important character in distinguishing hypodense small hepatocellular carcinoma from other hypodense diseases in the liver

  16. CT and MRI diagnosis of nasopharyneal angiofibroma

    International Nuclear Information System (INIS)

    Zhang Xiaoya; Liang Biling

    2007-01-01

    Objective: To analyze the CT and MRI manifestations of nasopharyneal angiofibroma. Methods: 21 cases of nasopharyneal angiofibroma are retrospectively analyzed according to the location, size, margin, density or signal of the tumor and the changes of surrounding bones. Results: The CT and MRI showed a nasopharyneal mass with well-defined margin, uniform density or signal and remarkably enhanced. The sphenomaxillary fossa was enlarged and the posterior wall of maxillary sinus was, compressed and displaced without bone destruction. The surrounding bone appeared to be compressed, molded, absorbed or destroyed. Conclusion: CT examination can usually provide diagnostic information, but the combination of CT and MRI can be better contributed to the diagnosis, location and stage classification of nasopharyneal angiofbroma. (authors)

  17. CT diagnosis of simple renal cysts

    International Nuclear Information System (INIS)

    Nanakawa, Seito; Yasunaga, Tadamasa; Tsuchigame, Tadatoshi; Kawano, Shoji; Takahashi, Mutsumasa; Fukui, Koutaro.

    1987-01-01

    CT is indispensable in the evaluation of renal masses, providing noninvasive and clear transverse images. With wider clinical application of CT, renal cysts have been found more frequently. CT examinations on 500 patients, who underwent CT for the diagnosis of renal diseases except for renal cysts, have been reviewed and analysed. The incidence of renal cysts was 9.6 % without prediction for sexes, but the incidence and sizes of the cysts increased with the advancing age. The upper portion of the kidneys was more frequently involved, but there was no relationship between number, sex and age of the patients. Since renal cysts produce mass effect in the kidneys, understanding of the nature and incidence of the renal cysts is important in diagnosing renal mass lesions. (author)

  18. Acute ureterolithiasis: Incidence of secondary signs on unenhanced helical CT and influence on patient management

    Energy Technology Data Exchange (ETDEWEB)

    Ege, G. E-mail: gurkanege@yahoo.com; Akman, H.; Kuzucu, K.; Yildiz, S

    2003-12-01

    AIM: The purpose of this study was to determine the incidence of secondary signs associated with ureteral stones on unenhanced helical computed tomography (CT) of patients with acute renal colic, and to correlate these with patient management and outcome. MATERIALS AND METHODS: One hundred and ten patients with ureterolithiasis were evaluated prospectively for the secondary signs of obstruction on unenhanced helical CT. Our attention was focused primarily on the presence or absence of seven secondary signs on unenhanced helical CT, including hydronephrosis, unilateral renal enlargement, perinephric oedema, unilateral absence of the white pyramid, hydroureter, periureteral oedema and lateroconal fascial thickening. RESULTS: Of the 110 patients, 91 (82.7%) had hydroureter, 88 (80%) had hydronephrosis, 65 (59%) had periureteric oedema and 63 (57.2%) had unilateral renal enlargement. Ninety stones passed spontaneously and 21 required intervention. CONCLUSION: Secondary signs of urinary tract obstruction are useful and supportive findings in interpretation of the CT examination. In our experience, the most reliable signs indicating ureteral obstruction are hydroureter, hydronephrosis, periureteral oedema and unilateral renal enlargement, respectively. In addition, stones larger than 6 mm, located within the proximal two thirds of the ureter, and seen associated with five or more the secondary signs of obstruction, are more likely to require endoscopic removal and/or lithotripsy.

  19. Spiral (Helical) computed tomographic imaging for the diagnosis of bile duct cancer. Vascular and pancreatic invasions

    International Nuclear Information System (INIS)

    Kon, Masanori

    1997-01-01

    The development of several imaging techniques for diagnosing bile duct cancer have improved, however, its diagnosis at the early stage is still difficult. We discuss the significance of the spiral (helical) computed tomography (SCT) imaging for the diagnosis of bile duct cancer at an early stage. We performed, as a preoperative examination, SCT under intravenous angiography (IV-SCT) for all cases, which included 233 cases of benign bile duct diseases, 42 cases of gallbladder cancer and 22 cases of bile duct cancer. The accuracy rate of diagnosis ability of 42 cases of gallbladder cancer by IV-SCT was 91%, and that of portal vein invasion was 91%. In the cases of bile duct cancer, IV-SCT showed destructive images of the bile duct wall and the tumor images invaded into the pancreatic parenchyma, in the cases of invasion at the splenic vein and confluence site of the portal vein, IV-SCT gave clearer 3D images than conventional angiography. The accuracy rate of diagnosing pancreatic invasion in bile duct cancer by IV-SCT was 80%. However, it is still difficult to determine completely the layer structures of the bile duct and the invasion into the walls along the long axis. As the future development of SCT for the diagnosis of bile duct cancer, we expect further progression of diagnosis ability of bile duct cancer and the invasion level by the applying high resolution thin-section CT images or endoscopical images of the luminal organs in examining the bile duct. (K.H.)

  20. CT diagnosis of hypoxic ischemic encephalopathy

    International Nuclear Information System (INIS)

    Zhao Xiang; Ma Jiwei; Wu Lide

    2004-01-01

    Objective: To explore CT characteristics of hypoxic ischemic encephalopathy (HIE), and to improve the accuracy of CT diagnosis. Methods: 50 cases of neonatal asphyxia in perinatal period diagnosed as hypoxic ischemic encephalopathy by CT was analyzed. Results: The main manifestation of hypoxic ischemic encephalopathy is cerebral edema and intracranial hemorrhage. Focal or diffuse hypo-dense lesion and hyper-dense area in various location and morphology were seen on CT images. (1) Localized diffuse hypo-dense area in 1 or 2 cerebral lobe were found in 17 cases, and the lesions were localized in frontal lobe (n=6), in frontotemporal lobe (n=5), and in temporo-occipital lobe (n=6). (2) Hypo-density region involving more than three cerebral lobes were found in 18 cases, and abnormalities were found in frontotemporal and parietal lobe (n=8), accompanying with subarachnoid hemorrhage (n=2); in frontal, temporal and occipital lobe (n=6), in which cerebral hemorrhage was complicated (n=1); and in other cerebral lobe (n=4). (3) Diffuse low-density region in all cerebral lobe were found in 15 cases, in which subarachnoid hemorrhage was complicated in 4 cases, and ventricular hemorrhage was found in 2 case. Conclusion: CT imaging plays an important role in diagnosis of hypoxic ischemic encephalopathy and has shown its clinical value

  1. Usefulness and limit of CT diagnosis on appendicitis

    International Nuclear Information System (INIS)

    Kuchiki, Megumi; Takanashi, Toshiyasu; Yamaguchi, Koichi.

    1997-01-01

    CT was performed in 104 patients with abdominal pain suspected appendicitis. CT showed positive finding (abnormal appendix, appendicolith, pericecal inflammatory change, fluid collection, LN swelling, abscess) and complication of appendicitis clearly. CT diagnosis showed high accuracy than clinical diagnosis. CT proved its usefulness especially only CT imaging showed the correct diagnosis. On the other hand, diverticulitis and terminal ileitis common diagnostic disease of appendicitis showed similar clinical appearance and CT image, caused to be difficult to diagnose correctly. In the cases showing similar image to appendicitis or atypical image, CT also proved its limit of the diagnosis on appendicitis. (author)

  2. Technical evaluation of DIC helical CT and 3D image for laparoscopic cholecystectomy

    International Nuclear Information System (INIS)

    Shibuya, Kouki; Uchimura, Fumiaki; Haga, Tomo

    1995-01-01

    Recently Laparoscopic Cholecystectomy (L.C.) was widely accepted for its low invasive procedure. Before L.C., it is important to understand anatomical recognization of biliary tree. We examined DIC Helical CT before L.C., and reconstructed 3D Cholangiographic image. We evaluated physical potentiality of Helical CT using Section Sensitivity Profiles (SSP) with 5, 10 mm slice thickness on 360deg linear interpolation. And we analyzed most useful 3D image for biliary tree. Results showed the SSP depended on slice thickness (X-ray beam width) and table movement at same reconstruction spacing. The peak of SSP depended on slice thickness (X-ray beam width) and reconstruction spacing at same table movement. Clinically, it was necessary under 5 mm/rotation table movement and 5 mm thickness for acquiring volume image data. 3D Cholangiographic image reconstructed with 1 mm spacing image was useful in evaluation of relationship of anatomical biliary tree. (author)

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

    International Nuclear Information System (INIS)

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

    2004-01-01

    Respiratory motion degrades anatomic position reproducibility during imaging, necessitates larger margins during radiotherapy planning and causes errors during radiation delivery. Computed tomography (CT) scans acquired synchronously with the respiratory signal can be used to reconstruct 4D CT scans, which can be employed for 4D treatment planning to explicitly account for respiratory motion. The aim of this research was to develop, test and clinically implement a method to acquire 4D thoracic CT scans using a multislice helical method. A commercial position-monitoring system used for respiratory-gated radiotherapy was interfaced with a third generation multislice scanner. 4D cardiac reconstruction methods were modified to allow 4D thoracic CT acquisition. The technique was tested on a phantom under different conditions: stationary, periodic motion and non-periodic motion. 4D CT was also implemented for a lung cancer patient with audio-visual breathing coaching. For all cases, 4D CT images were successfully acquired from eight discrete breathing phases, however, some limitations of the system in terms of respiration reproducibility and breathing period relative to scanner settings were evident. Lung mass for the 4D CT patient scan was reproducible to within 2.1% over the eight phases, though the lung volume changed by 20% between end inspiration and end expiration (870 cm 3 ). 4D CT can be used for 4D radiotherapy, respiration-gated radiotherapy, 'slow' CT acquisition and tumour motion studies

  4. Assessment of hepatic arterial variation using multidetector helical CT-angiography

    International Nuclear Information System (INIS)

    Lee, Dong Hoon; Lee, Jun Woo; Jun, Woong Bae; Lee, Suk Hong

    2001-01-01

    To evaluate the anatomy of the hepatic artery and normal variants using oblique thick-slab maximal intensity projection (MIP) 3-D CT angiography and multidetector helical CT technology. In 70 patients, axial three-phase CT together with multidetector helical CT and a nonionic contrast agent was used to evaluate liver disease. During the early arterial phase, the parameters were as follow: slice thickness, 2.5 mm; table speed, 15 mm/rotation, pitch, 6; contrast material, 4 ml/sec; total 120 ml. Using the MIP technique and an Advantage window voxtal 3.03 system (GE), the images obtained were reconstructed as 3D angiograms. In each case, the arterial anatomy and its variants were recorded. A typical anatomy was found in 53 cases (75.7%). Common variants were a left hepatic artery arising from the left gastric artery(8 cases, 11.4 %) and a right hepatic artery arising from the superior mesenteric artery(3 cases, 4.3%). Other variant cases were right hepatic artery arising from the gastroduodenal artery(2 cases, 2.9%), a proper hepatic artery arising from the left gastric artery (1 case, 1.4%), a hepatomesenteric trunk (1 case), a hepatogastric/splenomesenteric trunk(1 case), and a celiomesenteric trunk (1 case). 3-D hepatic angiography using multidetector helical CT technology is non-invasive and as accurate as conventional angiography for the evaluation of hepatic arterial anatomy. It is thus considered that 3-D CT angiography is very helpful for the evaluation of hepatic arterial anatomy prior to liver surgery such as transplantation or the treatment of hepatocellular carinoma

  5. Clinical application of helical CT 3D reconstruction for the dental orthopaedics

    International Nuclear Information System (INIS)

    Han Benyi; Jiang Xiaolu; Li Hongru

    2005-01-01

    Objective: To evaluate the clinical application of helical CT 3D reconstruction technique in the dental orthopaedics. Methods: The helical CT was performed with 3.0 mm slice thickness and 1.0 pitch in 41 patients with dental orthopaedics. The 3D reconstructions, including maximum intensity projection (MIP), surface shaded display (SSD), and multiplanar reconstructions (MPR), were made for all the cases. Results: Thirty-seven of the 41 patients showed malalignment, tilt, rotation, overlap of the teeth and the different space between the longitudinal axes of the teeth. Twenty-five cases of them have shown 36 buried teeth in all. The axial images covered all the information. SSD demonstrated the external contours and entire morphologies of the teeth and the mandible with the relationship of the teeth alignment and the mandible. MIP clearly manifested the full view and the longitudinal alignment of the teeth. Among the 36 buried teeth, there were 29 palatally and 7 labially presented teeth, and they were morphologically delineated on MIP through various angles. Conclusion: The helical CT 3D reconstruction is a new technique to display the stereoscopic configuration of teeth. The combination of axial images and MIP, SSD, and MPR provides valuable anatomic and diagnostic information helpful for the surgeons to structure and determine the treatment protocol for the dental orthopaedics. (authors)

  6. Evaluation of coronary artery disease by helical CT using retrospective ECG-gating

    International Nuclear Information System (INIS)

    Kawawa, Yoko

    2001-01-01

    The purpose of this study is to evaluate the usefulness of helical CT using retrospective ECG-gating for visualization of the coronary artery and detection of coronary artery disease. We performed a coronary artery phantom study and established this new application, with 1-mm collimation, 1-mm table increment, and 0.1-mm reconstruction (0.8 sec/rotation). Helical CT of 31 patients with 39 coronary artery diseases (34 coronary artery stenoses, 1 vasospastic angina, 1 coronary artery dissection, 1 coronary artery ectasia and 2 coronary artery aneurysms) was performed in a single breath hold and ECG-gating without and with intravenous injection of nonionic iodine contrast material. We selected the images which were not affected by cardiac motion from the reconstruction images, in order to visualize the coronary artery for detection of coronary artery disease. The coronary artery was well visualized in 32 out of 39 vessels (82%). A good visualization of the coronary artery was correlated with the heart rate. Further, in this well visualized group, coronary artery diseases were detected in 24 out of 31 cases (77%). One case of vasospastic angina was not included. It was difficult to detect coronary artery disease in cases of heavily calcified vessels or in the left circumflex artery. Helical CT using this retrospective ECG-gating is a useful noninvasive examination for evaluation of coronary artery disease. (author)

  7. Measurement of MV CT dose index for Hi-ART helical tomotherapy unit

    International Nuclear Information System (INIS)

    Wang Yunlai; Liao Xiongfei

    2010-01-01

    Objective: To evaluate the patient dose from Hi-ART MV helical CT imaging in image-guided radiotherapy. Methods: Weighted CT dose index (CTDI W ) was measured with PTW TM30009 CT ion chamber in head and body phantoms, respectively,for slice thicknesses of 2, 4, 6 mm with scanned range of 5 cm and 15 cm. Dose length products (DLP) were subsequently calculated. The CTDI W and DLP were compared with XVI kV CBCT and ACQSim simulator CT for routine clinical protocols. Results: An inverse relationship between CTDI and the slice thickness was found. The dose distribution was inhomogeneous owing to the attenuation of the couch. CTDI and DLP had close relationship with the slice thickness and the scanned range. Patient dose from MVCT was lower than XVI CBCT for head, but larger for body scan. Conclusions: CTDI W can be used to assess the patient dose in MV helical CT due to its simplicity for measurement and reproducibility. Regular measurement should be performed in QA and QC program. Appropriate slice thickness and scan range should be chosen to reduce the patient dose. (authors)

  8. Acute solitary localized pneumonia: CT diagnosis

    International Nuclear Information System (INIS)

    Li Tieyi

    1999-01-01

    Objective: To evaluate CT in the differential diagnosis of solitary localized pneumonia. Method: Only plain CT without contrast study was done because of different types of CT scanners weed. There were 25 cases with localized pneumonia with initial diagnosis as suspected peripheral bronchogenic carcinoma. All patients were over forty years of age, 84% 50-80 years, 13(52%) patients were asymptomatic, 5(20%) patients had bloody sputum. Results: The CT features were divided into three patterns: (1) irregular nodule with relatively well-defined margin, ground-glass opacity and a few punctuate high densities. (2) irregular nodule with sharply circumscribed, spiculate border and homogeneous density. (3) regular nodule with relatively well-defined margin, and homogeneous density. The third type was most frequent (60%) with predilection for the dorsal segments of the lower lobes, or the posterior basal segments. Of the 25 patients 3 had operation, the remaining cases were treated as pneumonia, the lesions were resolved in 18(82%) patients in 2-3 weeks. Conclusions: Sometimes it is very difficult to differentiate localized pneumonia from peripheral lung cancer on the basis of clinical presentation and imaging. The spiculate margins of irregular nodule shown on CT could be indeterminate on chest radiography, and as a result chest radiograph is helpful in differential diagnosis of localized pneumonia. Change in size of the lesion as observed at the same cross-section scan, smaller at mediastinal window than at lung window is in favor of localized pneumonia, however, with the exception of alveolar carcinoma, treatment with antibiotic therapy for a period of 2-3 weeks, helps differentiate these diseases

  9. Computer-aided diagnosis workstation and telemedicine network system for chest diagnosis based on multislice CT images

    Science.gov (United States)

    Satoh, Hitoshi; Niki, Noboru; Eguchi, Kenji; Ohmatsu, Hironobu; Kakinuma, Ryutaru; Moriyama, Noriyuki

    2009-02-01

    Mass screening based on multi-helical CT images requires a considerable number of images to be read. It is this time-consuming step that makes the use of helical CT for mass screening impractical at present. Moreover, the doctor who diagnoses a medical image is insufficient in Japan. To overcome these problems, we have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images, a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification and a vertebra body analysis algorithm for quantitative evaluation of osteoporosis likelihood by using helical CT scanner for the lung cancer mass screening. The functions to observe suspicious shadow in detail are provided in computer-aided diagnosis workstation with these screening algorithms. We also have developed the telemedicine network by using Web medical image conference system with the security improvement of images transmission, Biometric fingerprint authentication system and Biometric face authentication system. Biometric face authentication used on site of telemedicine makes "Encryption of file" and "Success in login" effective. As a result, patients' private information is protected. We can share the screen of Web medical image conference system from two or more web conference terminals at the same time. An opinion can be exchanged mutually by using a camera and a microphone that are connected with workstation. Based on these diagnostic assistance methods, we have developed a new computer-aided workstation and a new telemedicine network that can display suspected lesions three-dimensionally in a short time. The results of this study indicate that our radiological information system without film by using computer-aided diagnosis workstation and our telemedicine network system can increase diagnostic speed, diagnostic accuracy and

  10. CT diagnosis of neuroblastoma in childhood

    International Nuclear Information System (INIS)

    Li Xin; Zhang Liqun; Yang Zhiyong

    1997-01-01

    Purpose: To evaluate CT in the diagnosis of neuroblastoma in childhood. Materials and methods: Analysis of CT manifestations in 26 cases proved by operation and pathology, including neuroblastoma 21 cases, ganglioneuroblastoma 5 cases. Thorax 7 cases (27%), adrenal gland 16 cases (62%), abdomen-pelvis paravertebral sympathetic chain 3 cases (11%). Bolus injection of contrast medium was given in all cases. Results: Adrenal gland and posterior superior mediastinum were the most common sites for neuroblastoma. 73% of neuroblastoma had calcifications. Neuroblastoma was more commonly calcified than ganglioneuroblastoma. Metastases were also calcified. Degree of enhancement was associated with the type of neuroblastoma. Tumor extension into the spinal canal was seen in 2 cases. 43% neuroblastoma of adrenal directly invaded the kidney in 7 cases. Right lobe of liver was involved in 3 cases, metastases to liver in 1 case, enlargement of lymph nodes 19 cases. Approximately 68% of patients showed increase of urinary Vanilly-mandelic acid (VMA). Preoperative diagnostic accuracy was 92%. Conclusion: CT is recognized as a useful technique for the diagnosis of neuroblastoma. The site of predilection, calcification, lymph node metastases and VMA increase in urine or serum are important basis for diagnosis

  11. Peripancreatic vascular abnormalities complicating acute pancreatitis: contrast-enhanced helical CT findings

    International Nuclear Information System (INIS)

    Mortele, Koenraad J.; Mergo, Patricia J.; Taylor, Helena M.; Wiesner, Walter; Cantisani, Vito; Ernst, Michael D.; Kalantari, Babak N.; Ros, Pablo R.

    2004-01-01

    Objective: To determine the prevalence and morphologic helical computed tomography (CT) features of peripancreatic vascular abnormalities in patients with acute pancreatic inflammatory disease in correlation with the severity of the pancreatitis. Materials and methods: One hundred and fifty-nine contrast-enhanced helical CT scans of 100 consecutive patients with acute pancreatitis were retrospectively and independently reviewed by three observers. CT scans were scored using the CT severity index (CTSI): pancreatitis was graded as mild (0-2 points), moderate (3-6 points), and severe (7-10 points). Interobserver agreement for both the CT severity index and the presence of peripancreatic vascular abnormalities was calculated (K-statistic). Correlation between the prevalence of complications and the degree of pancreatitis was estimated using Fisher's exact test. Results: The severity of pancreatitis was graded as mild (n=59 scans), moderate (n=82 scans), and severe (n=18 scans). Venous abnormalities detected included splenic vein (SV) thrombosis (31 scans, 19 patients), superior mesenteric vein (SMV) thrombosis (20 scans, 14 patients), and portal vein (PV) thrombosis (17 scans, 13 patients). Arterial hemorrhage occurred in five patients (6 scans). In our series, no cases of arterial pseudoaneurysm formation were detected. The interobserver agreement range for scoring the degree of pancreatitis and the overall presence of major vascular abnormalities was 75.5-79.2 and 86.2-98.8%, respectively. The presence of the vascular abnormalities in correlation with the severity of pancreatitis was variable. Conclusion: Vascular abnormalities are relatively common CT findings in association with acute pancreatitis. The CT severity index is insufficiently accurate in predicting some of these complications since no statistically significant correlation between their prevalence and the severity of pancreatitis could be established

  12. CT portography by multidetector helical CT. Comparison of three rendering models

    International Nuclear Information System (INIS)

    Nakayama, Yoshiharu; Imuta, Masanori; Funama, Yoshinori; Kadota, Masataka; Utsunomiya, Daisuke; Shiraishi, Shinya; Hayashida, Yoshiko; Yamashita, Yasuyuki

    2002-01-01

    The purpose of this study was to assess the value of multidetector CT portography in visualizing varices and portosystemic collaterals in comparison with conventional portography, and to compare the visualizations obtained by three rendering models (volume rendering, VR; minimum intensity projection, MIP; and shaded surface display, SSD). A total of 46 patients with portal hypertension were examined by CT and conventional portography for evaluation of portosystemic collaterals. CT portography was performed by multidetector CT (MD-CT) scanner with a slice thickness of 2.5 mm and table feed of 7.5 mm. Three types of CT portographic models were generated and compared with transarterial portography. Among 46 patients, 48 collaterals were identified on CT transverse images, while 38 collaterals were detected on transarterial portography. Forty-four of 48 collaterals identified on CT transverse images were visualized with the MIP model, while 34 and 29 collaterals were visualized by the VR and SSD methods, respectively. The average CT value for the portal vein and varices was 198 HU with data acquisition of 50 sec after contrast material injection. CT portography by multidetector CT provides excellent images in the visualization of portosystemic collaterals. The images of collaterals produced by MD-CT are superior to those of transarterial portography. Among the three rendering techniques, MIP provides the best visualization of portosystemic collaterals. (author)

  13. CT portography by multidetector helical CT. Comparison of three rendering models

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, Yoshiharu; Imuta, Masanori; Funama, Yoshinori; Kadota, Masataka; Utsunomiya, Daisuke; Shiraishi, Shinya; Hayashida, Yoshiko; Yamashita, Yasuyuki [Kumamoto Univ. (Japan). School of Medicine

    2002-12-01

    The purpose of this study was to assess the value of multidetector CT portography in visualizing varices and portosystemic collaterals in comparison with conventional portography, and to compare the visualizations obtained by three rendering models (volume rendering, VR; minimum intensity projection, MIP; and shaded surface display, SSD). A total of 46 patients with portal hypertension were examined by CT and conventional portography for evaluation of portosystemic collaterals. CT portography was performed by multidetector CT (MD-CT) scanner with a slice thickness of 2.5 mm and table feed of 7.5 mm. Three types of CT portographic models were generated and compared with transarterial portography. Among 46 patients, 48 collaterals were identified on CT transverse images, while 38 collaterals were detected on transarterial portography. Forty-four of 48 collaterals identified on CT transverse images were visualized with the MIP model, while 34 and 29 collaterals were visualized by the VR and SSD methods, respectively. The average CT value for the portal vein and varices was 198 HU with data acquisition of 50 sec after contrast material injection. CT portography by multidetector CT provides excellent images in the visualization of portosystemic collaterals. The images of collaterals produced by MD-CT are superior to those of transarterial portography. Among the three rendering techniques, MIP provides the best visualization of portosystemic collaterals. (author)

  14. Application of low dose multi-slice helical CT in orbital trauma patients

    International Nuclear Information System (INIS)

    Yang Rui; Dai Limei; Li Jianying; Wang Fengyan; Du Guoquan

    2010-01-01

    Objective: To investigate the most appropriate low radiation dose in multi-slice CT (MSCT) scans for orbital trauma patients. Methods: Thirty trauma patients with suspected orbital fractures who underwent helical CT scans with a 64-MSCT using regular dose were selected. Noise was artificially introduced to the axial images using an image space noise addition tool to simulate 6 sets of lower dose scans with tube current of 30, 70, 100, 140, 170 and 200 mA, respectively. The lowest tube current with adequate image quality for confident diagnosis was determined based on the evaluation of the overall image quality and fracture detection on images at different dose levels. The determined lowest tube current was then validated using clinical scans. Radiation dose related parameters CTDIvol, DLP, ED were also recorded. Image quality was evaluated according to its low-density resolution, noise and structure clarity and characterized into 5-grades of excellent, good, fair, worse and worst. Rank sum test and χ 2 test were used for statistics. Results: In 30 trauma patients with regular dose of 300 mA, there were 30 cases of orbital fracture, 19 cases of intraorbital emphysema, 12 cases of ocular muscle injury and 1 case of intraorbital foreign body. These changes could still be clearly observed and correctly diagnosed when the tube current was reduced to as low as 70 mA. However, the overall image quality was mostly fair. At the simulated dose of 100 mA, the majority of images were characterized as excellent or good, and there was no statistical difference compared with that of regular dose scans (P>0.05). In the clinical evaluation for 20 orbital trauma patients with the reduced tube current of 100 m A , the majority of images were judged to be excellent (9 cases) or good (17 cases) and fair (4 cases). The radiation dose (0.29 mSv) was reduced by 70% compared with that of regular tube current of 300 mA (0.86 mSv). Conclusion: The tube current of MSCT may be used as low as

  15. Multidetector-row helical CT: analysis of time management and workflow

    Energy Technology Data Exchange (ETDEWEB)

    Roos, Justus E.; Desbiolles, Lotus M.; Willmann, Juergen K.; Weishaupt, Dominik; Marincek, Borut; Hilfiker, Paul R. [Institute of Diagnostic Radiology, University Hospital Zurich (Switzerland)

    2002-03-01

    The purpose of this study was to evaluate time management and workflow for multidetector-row helical CT (MDCT). Time for patient and data handling of at total of 580 patients were evaluated at two different time periods (December 1999, August 2000), each for the following baseline measurements: (a) change of clothes/instruction; (b) patient placement on the CT table/i.v. catheter; (c) CT planning and programming; (d) CT data acquisition; (e) CT data reconstruction; (f) CT data storage/printing. All imaging was performed on a Somatom Volume Zoom (Siemens, Erlangen, Germany). Time measurements summarized for different CT protocols revealed the following: (a) 5:01 min ({+-}2.06 min); (b) 4:36 min ({+-}2.43 min); (c) 4:11 min ({+-}2.55 min); (d) 0:43 min ({+-}0.15 min); (e) 6:59 min ({+-}2.39 min); (f) 09:51 min ({+-}3.51 min). Planning and programming was most time-consuming for CT angiography, whereas chest and abdominal CT needed only 3:26 and 3:30 min, respectively. Reconstruction time was highest for HRCT (9:22 min) and CTA (9:03 min). Data storage/printing was most time-consuming for HRCT (13:02 min), followed by combined neck-chest-abdomen examinations (12:19 min). Comparing the two time periods, during which a software update was performed, a mean time reduction of 4:31 min per patient (15%, p<0.001) was achieved. Whereas CT data acquisition time is no longer a problem with MDCT, patient management, data reconstruction, and data storage are the most time-consuming parts. Well-trained technicians, state-of-the-art workstations, and fast networking are the most important factors to improve workflow. (orig.)

  16. EFFECTIVENESS OF CT IN DIAGNOSIS OF PROPTOSIS

    Directory of Open Access Journals (Sweden)

    Vikas Agrawal

    2017-07-01

    Full Text Available BACKGROUND Orbit is a pyramidal shaped anatomical space bound by orbital bones whose apex is continued posteriorly as the optic canal and rectangular base opens into the face. Though a series of canal, fissures and foramina communicate with extra orbital compartment, it is a closed compartment with broad opening anteriorly. Orbit contains the eye ball, extra ocular muscles, vascular elements, nerves, lacrimal gland and connective tissue. Proptosis is defined as an abnormal protrusion of the eyeball. MATERIALS AND METHODS Total 32 patients referred from various departments mainly from ophthalmology and medicine with history and clinical features suggestive of proptosis were evaluated in our department and after proper history taking and clinical examination, Computed Tomography (CT scan and histopathological diagnosis was done. RESULTS The age of the patients ranged from 1-55 years. Mass lesions (46.87% were the most common cause of proptosis followed by inflammatory lesions (37.5%. Trauma, vascular lesions and congenital conditions were infrequent causes of proptosis. Unilateral proptosis was more frequent (84.37% than bilateral proptosis (15.62% and thyroid ophthalmopathy accounted for 60% of bilateral proptosis cases. CONCLUSION Mass lesions were the most common cause of proptosis followed by inflammatory lesions. CT scanning should be the chief investigation in evaluation of lesions causing proptosis. It is the most useful in detecting, characterising and determining the extent of disease process. The overall accuracy of CT scan in diagnosis of proptosis was 96.87%.

  17. CT and MRI diagnosis of intracranial chondroma

    International Nuclear Information System (INIS)

    Liu Xuejun; Sui Qinglan

    2006-01-01

    Objective: To summarize and study the features of intracranial chondroma on CT and MRI imaging. Methods: CT and MRI findings of ten cases of intracranial chondroma proved by surgery and pathology from 1994. 1 to 2004.9 were retrospectively analyzed. Results: Among 10 cases, 4 cases were located at the skull base, 4 cases at convexity, 1 case at the region of falx cerebri, and 1 case within the brain parenchyma. CT scans showed obvious calcification and clear border of the tumors in 10 cases, mixed attenuation in 9 eases, and adjacent bone invasion in 5 cases. 4 cases of MRI scans showed hypointense signal on T 1 and T 2 -weighted images in calcified element of the tumor, intermediate to hypointense signal intensity on T 1 -weighted image, and hyperintense signal intensity on T 2 -weighted image in parenchyma of the tumor. 4 cases of CT scans showed slightly enhancement. Conclusion: Intracranial chondroma are often originated from synchondrosis of the skull base, convexity of brain and region of falx cerebri. Obvious calcification may be seen in most cases. Slightly enhancement and marked delayed contrast enhancement were characteristic. The accurate diagnosis still depends on pathology. (authors)

  18. CT diagnosis of abdominal ectopic pheochromocytoma

    International Nuclear Information System (INIS)

    Zhang Yuping; Zhao Zhiying

    2010-01-01

    Objective: To discuss the value of CT in diagnosis of abdominal ectopic pheochromocytoma. Methods: CT findings of 5 cases surgically and pathologically proved with ectopic pheochromocytoma were retrospectively analyzed. Results: Soft tissue mass with light asymmetry enhancement was found between the abdominal aorta and the inferior vena ca-va in one case. 1 case was completely cystic with light enhancement of the cystwall located in front of the left side of the abdominal aorta. 1 case of large solid mass occurred between the renal hilum and the tail of pancreas, with irregular shape, unclear boundary, central necrosis, calcification and obviously enhancement at the solid part. 2 cases showed as oval soft lump with even density, moderate strengthening located before the abdominal aorta. Paroxysmal hypertension occurred in 3 cases and didn't in 2 cases. Hypertension happened in 1 case during the operation because of stimulation. Blood pressure appeared in 1 case during and after operation. Blood and urinary catecholamine increased significantly in 4 cases. Conclusion: Ectopic pheochromocytoma mainly located surround the abdominal aorta with diverse CT performance. It is helpful for diagnosing when finding a lesion locates at the specified sites combined with typical clinical presentation. CT can not only depict small tumor, but also can show the relationship with surrounding structure, and it provides important information for the operation and prognosis. (authors)

  19. Helical CT angiography of renal arteries: two-years of experience

    International Nuclear Information System (INIS)

    Beregi, J.P.; Louvegny, S.; Ceugnart, L.; Willoteaux, S.; Elkohen, M.; Desmoucelle, F.; Deklunder, G.; Wattinne, L.

    1997-01-01

    To evaluate the role of helical CT angiography (CTA) in the detection of renal artery stenosis in hypertensive patients. We studied 300 hypertensive patients (50 prospectively and 250 consecutively) with CTA and arteriography (n = 118). Helical acquisition (collimation 3 mm; pitch = 1, 20 seconds acquisition time) was performed 20-45 seconds after contrast injection (300 mgl/ml; 120 ml, 4 ml/sec. Transverse axial views and 3D reconstructions were analysed (360 deg interpolation algorithm, 1 mm overlapped). In the prospective series, CTA sensibility was 100 % for main renal artery stenoses and specificity was 98.2 %; however 7/32 renal accessory arteries were not visualized. In the 300 patients studies, seventy-four stenoses were detected. There were 5 false-positive and 5 false-negative studies. Secondary hypertension was detected in 26 % of patients (including 14 cases of adrenal hyperplasia). CTA is a promising technique for the detection of renal artery stenosis in hypertensive patients. (authors)

  20. CT diagnosis of blunt laryngeal trauma

    International Nuclear Information System (INIS)

    Kong Fanbin; Xia Ruigan; Hu Libin

    2000-01-01

    Objective: To analyze CT findings of blunt laryngeal trauma (BLT) and evaluate the value of CT in the diagnosis of BLT. Methods: CT diagnosis and treatment of 16 patients with BLT were reviewed. Results: Soft-tissue injuries were detected in five cases including swelling of the aryepiglottic folds, the false or true vocal cords and airway narrowing in four, and left cricoarytenoid dislocation and card paralysis in one. Supraglottic injuries in two cases including c fractures of the epiglottis in 2 and associated with a laceration of the aryepiglottic folds and the hypopharynx. Glottic injuries in four cases including ventricle fracture of the right thyroid ala in one and midline ventricle or comminute fractures of the thyroid cartilage in three, a square segment of cartilage was depressed into the larynx, and the true vocal cords and the anterior commissure were disrupted in one of this series. Subglottic injuries in five cases including cricoid ring fracture on the opposite side following a lateral force in one, with the fragment depressed into the larynx. Two showed marked comminution of the cricoid ring. Midline vertical fracture of the posterior cricoid plate associated with the laceration of the first tracheal ring in one, and one presented marked disruption of the right cricothyroid joint. Conclusion: CT clearly shows the extent of cartilaginous injury and displacement, related soft-tissue changes and the degree of resulting airway encroachment, and it may be successfully used to determine the need for open exploration and repair in selected cases of blunt trauma to the larynx

  1. Three-dimensional helical (spiral) CT angiography. Visualization of vessels in the maxillofacial regions

    International Nuclear Information System (INIS)

    Hanawa, Shigeo; Sakamoto, Hidetomo; Mori, Shin-ichiro; Kagawa, Toyohiro; Seze, Ryosuke; Ishioka, Hisakazu; Tashiro, Himiko; Ogawa, Kazuhisa; Wada, Tadako

    1998-01-01

    Authors performed the contrast helical CT for tumors on the maxillofacial regions, and reconstituted these data into the three-dimensional helical (spiral) CT angiography (CTA). Furthermore the conditions of photographing and the clinical significance of CTA were discussed. The subjects were 24 cases (including 13 of malignant tumors, 4 of benign tumors, 4 of inflammation and 3 of malformations), to which the contrast helical CT was performed transvenously. The photographing condition was set in principal to 140 kV of the tube voltage, 160 (200) mA of the tube current, 3 mm of the X-ray beam width, 3 mm/sec (pitch=1) of the turn-table moving speed. The relationship between the beam width and the pitch was determined by the phantom experiments. The scanning was carried out maximally for continuous 60 sec as the scanning time of a turn/sec. Of all cases, CTA visualized three-dimensionally vessels, but it was hard in the total carotid arteries and the internal-external carotid arteries. Authors analyzed the axial and the multiplanar reconstitution (MPR) images as the two-dimensional display, and the surface rendering (SR), the volume rendering and the maximum intensity projections (MIP) as the three-dimensional display. The axial and MPR image of the facial arteries and the lingual arteries as the branched vessels from the external carotid arteries were recognized easily. By SR, it was easily to understand the anatomical relationship among vessels, gnathic bone and cervical vertebrae, and by MIP sufficiently observe the concentration dependent calcification of the vessel walls. Three-dimensional CTA is very useful to get the three-dimensional visual information about the anatomical structures of the maxillofacial regions which is necessary for oral surgeons to plan the pre-operational strategies. (K.H.)

  2. The role of 3D Helical CT in the reconstructive treatment of maxillofacial cancers

    International Nuclear Information System (INIS)

    De Rosa, V.; Ziviello, M.; Ionna, F.; Mozzillo, N.; Parascandolo, S.

    2000-01-01

    Purpose of this work is to investigate the role of Helical CT and the usefulness of three-dimensional (3D) imaging for pre-operative planning and follow-up of reconstructive maxillofacial surgery with alloplastic material in neoplastic disease involving this region. From 1996 to 1999 eleven patients were examined with Helical CT and 3D images for planning of maxillofacial plastic and reconstructive surgery for advanced cancer of this anatomically complex region. A 3D-modulated titanium mesh (100%) or micro nets was used to rebuild the anterior surface of maxillary bone and the orbital floor. The mesh was cut to the appropriate size and shape and curved where necessary. Within the residual sinusal cavity a siliconed filling was used surmounting an acrylic prosthesis with dental arch to rebuild the palate. A rehydrated bovine pericardium was affixed and moduled on the borders in two cases only. Three-dimensionally reconstructed CT images were obtained preoperatively and at least 6 months postoperatively in all patients. The images were generated on a computer workstation using the shaded surface display (SSD) software with threshold values ranging 425 to 630 HU, and a more closed window for the imaging of titanium mesh/bone interface in the post surgical follow-up. It was obtained an excellent complete spatial depiction of maxillo facial region both before and after surgery, with no artefacts so important as to affect the 3D reconstruction process and the image quality. Together with the head-neck surgical team it could be worked for preoperative planning through CT scans by different 3D points of view. The 3D reconstructed follow-up scans showed good filling of the defect in the area where the titanium mesh had been used. Then efficacious bone modelling and good biocompatibility of the alloplastic material were seen in all patients, with no inflammatory reactions. Titanium is a well-known material, which is widely used for cranioplasty. It is a radiolucent, non

  3. Usefulness of the helical CT in gastro intestinally caused acute abdomen

    International Nuclear Information System (INIS)

    Cruz, R. A. de la; Martel, J.; Albillos, J. C.; Oliver, J. M.; Lopez, J.; Trapero, M. A.

    2000-01-01

    At present, there is a vivid debate on the role of the Helical CT (HCT) in the acute abdomen, principally on the usefulness of the non contrast HCT. We aim to present the most common semiological findings and the differential diagnoses, and to give a short description of the indications and protocols, according to the existing literature and to our experience with HCT during the last three years. We believe that the generalization of the use of HCT in emergencies avoid unnecessary surgery and shorten observation times on many occasions, with clear benefits in the clinical management of the patients. (Author) 30 refs

  4. The role of unenhanced helical CT in the evaluation of suspected renal colic and atypical abdominal pain in children

    International Nuclear Information System (INIS)

    Eshed, Iris; Witzling, Michaela

    2002-01-01

    Background: Urolithiasis in children has a different pattern of presentation than in adults and its incidence is lower. Unenhanced helical CT (UEHCT) for suspected urinary tract calculi in adults has high sensitivity and specificity for detecting even minute calculi. UEHCT has been proposed as a fast and sensitive method for identifying urinary stones in children. However, to our knowledge, the role of UEHCT and its value in the diagnostic work-up of urinary stones in children has not been studied. Objective: To evaluate the significance of UEHCT as a diagnostic tool for urinary stones in children. Materials and methods: We retrospectively analysed data on 20 children who underwent UEHCT during 1999-2000. Results: Findings on UEHCT were significant in establishing a diagnosis in only seven patients and only three were shown to have urinary stones. Only one significant finding was found in the group who underwent UEHCT without prior US. US performed prior to UEHCT was a significant screening tool, and when results were equivocal, UEHCT further helped in establishing diagnosis. Conclusions: We propose that US be the first imaging modality in children with suspected urolithiasis. When the result of this examination is uncertain or abnormal, UEHCT will probably add further information which will contribute to the diagnosis. (orig.)

  5. Motion tolerant iterative reconstruction algorithm for cone-beam helical CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hisashi; Goto, Taiga; Hirokawa, Koichi; Miyazaki, Osamu [Hitachi Medical Corporation, Chiba-ken (Japan). CT System Div.

    2011-07-01

    We have developed a new advanced iterative reconstruction algorithm for cone-beam helical CT. The features of this algorithm are: (a) it uses separable paraboloidal surrogate (SPS) technique as a foundation for reconstruction to reduce noise and cone-beam artifact, (b) it uses a view weight in the back-projection process to reduce motion artifact. To confirm the improvement of our proposed algorithm over other existing algorithm, such as Feldkamp-Davis-Kress (FDK) or SPS algorithm, we compared the motion artifact reduction, image noise reduction (standard deviation of CT number), and cone-beam artifact reduction on simulated and clinical data set. Our results demonstrate that the proposed algorithm dramatically reduces motion artifacts compared with the SPS algorithm, and decreases image noise compared with the FDK algorithm. In addition, the proposed algorithm potentially improves time resolution of iterative reconstruction. (orig.)

  6. Radiological diagnosis of chest wall tuberculosis: CT versus chest radiograph

    International Nuclear Information System (INIS)

    Liu Fugeng; Pan Jishu; Chen Qihang; Zhou Cheng; Yu Jingying; Tang Dairong

    2006-01-01

    Objective: To evaluate the role of CT or Chest radiograph in diagnosis of chest wall tuberculosis. Methods: The study population included 21 patients with chest wall tuberculosis confirmed by operation or biopsy. Chest radiograph and plain CT were performed in all eases, while enhanced CT in 9 cases, and all images were reviewed by 2 radiologists. Results: Single soft tissue mass of the chest wall was detected in all cases on CT, but not on chest radiograph(χ 2 =42.000, P 2 =4.421, P<0.05). Conclusion: CT, especially enhanced CT scan is the first choice in the diagnosis of chest wall tuberculosis. (authors)

  7. Preoperative evaluation of renal anatomy and renal masses with helical CT, 3D-CT and 3D-CT angiography.

    Science.gov (United States)

    Toprak, Uğur; Erdoğan, Aysun; Gülbay, Mutlu; Karademir, Mehmet Alp; Paşaoğlu, Eşref; Akar, Okkeş Emrah

    2005-03-01

    The aim of this prospective study was to determine the efficacy of three-dimensional computed tomography (3D-CT) and three-dimensional computed tomographic angiography (3D-CTA) that were reconstructed by using the axial images of the multiphasic helical CT in the preoperative evaluation of renal masses and demonstration of renal anatomy. Twenty patients that were suspected of having renal masses upon initial physical examination and ultrasonographic evaluation were examined through multiphasic helical CT. Two authors executed CT evaluations. Axial images were first examined and then used to reconstruct 3D-CT and 3D- CTA images. Number, location and size of the renal masses and other findings were noted. Renal vascularization and relationships of the renal masses with the neighboring renal structures were further investigated with 3D-CT and 3D-CTA images. Out of 20 patients, 13 had histopathologically proven renal cell carcinoma. The diagnoses of the remaining seven patients were xanthogranulomatous pyelonephritis, abscess, simple cyst, infected cyst, angiomyolipoma, oncocytoma and arteriovenous fistula. In the renal cell carcinoma group, 3 patients had stage I, 7 patients had stage II, and 3 patients had stage III disease. Sizes of renal cell carcinoma masses were between 23 mm to 60 mm (mean, 36 mm). Vascular invasion was shown in 2 renal cell carcinoma patients. Collecting system invasion was identified in 11 of 13 renal cell patients. These radiologic findings were confirmed with surgical specimens. Three-dimensional CT and 3D-CTA are non-invasive, effective imaging techniques for the preoperative evaluation of renal masses.

  8. Computer-aided diagnosis workstation and data base system for chest diagnosis based on multihelical CT images

    International Nuclear Information System (INIS)

    Satoh, H.; Niki, N.; Eguchi, K.; Masuda, H.; Machida, S.; Moriyama, N.

    2006-01-01

    We have provided diagnostic assistance methods to medical screening specialists by developing a lung cancer screening algorithm that automatically detects suspected lung cancers in helical CT images and a coronary artery calcification screening algorithm that automatically detects suspected coronary artery calcification. We also have developed electronic medical recording system and prototype internet system for the community health in two or more regions by using the Virtual Private Network router, Biometric fingerprint authentication system and Biometric face authentication system for safety of medical information. The results of this study indicate that our computer-aided diagnosis workstation and network system can increase diagnostic speed, diagnostic accuracy and safety of medical information. (author)

  9. Hepatic parenchymal perfusion abnormalities after pancreaticobiliary surgery. Evaluation with dynamic helical CT

    International Nuclear Information System (INIS)

    Mitsuzaki, K.; Yamashita, Y.; Ogata, I.; Nishiharu, T.; Urata, J.; Takahashi, M.

    1998-01-01

    Purpose: To evaluate perfusion abnormalities of the liver after pancreaticobiliary surgery. Material and Methods: We retrospectively evaluated 128 patients with pancreaticobiliary malignant tumors who had been examined both before and after surgery by means of helical CT of the liver. An infusion of 3 ml/s of 60% nonionic contrast material was followed by helical CT of the liver in a sequential arterial phase, portal venous phase, and equilibrium phase. Results: Of 128 patients, we followed 97. In 21 patients (22%) we found 47 lesions with perfusion abnormalities that were detected 1-33 months (mean 6.6 months) after the operation. All patients were asymptomatic. The shape of each perfusion abnormality was characterized as geographic (n=23, 47%), wedge-shaped (n=21, 45%), or round (n=3, 8%). The abnormalities were seen in the arterial phase in 46 lesions (98%), in the portal venous phase in 18 lesions (38%), and in the equilibrium phase in 1 lesion (0.2%). In all lesions, the size either decreased spontaneously, or it remained unchanged for more than one year. Conclusion: Perfusion abnormalities of the liver may occur in patients who undergo pancreaticobiliary surgery. These findings should not be confused with hypervascular metastases. (orig.)

  10. Hepatic parenchymal perfusion abnormalities after pancreaticobiliary surgery. Evaluation with dynamic helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Mitsuzaki, K.; Yamashita, Y.; Ogata, I.; Nishiharu, T.; Urata, J.; Takahashi, M. [Kumamoto Univ., School of Medicine, Dept. of Radiology (Japan)

    1998-05-01

    Purpose: To evaluate perfusion abnormalities of the liver after pancreaticobiliary surgery. Material and Methods: We retrospectively evaluated 128 patients with pancreaticobiliary malignant tumors who had been examined both before and after surgery by means of helical CT of the liver. An infusion of 3 ml/s of 60% nonionic contrast material was followed by helical CT of the liver in a sequential arterial phase, portal venous phase, and equilibrium phase. Results: Of 128 patients, we followed 97. In 21 patients (22%) we found 47 lesions with perfusion abnormalities that were detected 1-33 months (mean 6.6 months) after the operation. All patients were asymptomatic. The shape of each perfusion abnormality was characterized as geographic (n=23, 47%), wedge-shaped (n=21, 45%), or round (n=3, 8%). The abnormalities were seen in the arterial phase in 46 lesions (98%), in the portal venous phase in 18 lesions (38%), and in the equilibrium phase in 1 lesion (0.2%). In all lesions, the size either decreased spontaneously, or it remained unchanged for more than one year. Conclusion: Perfusion abnormalities of the liver may occur in patients who undergo pancreaticobiliary surgery. These findings should not be confused with hypervascular metastases. (orig.).

  11. Assessment of intraocular foreign bodies by helical-CT multiplanar imaging

    International Nuclear Information System (INIS)

    Papadopoulos, A.; Fotinos, A.; Maniatis, V.; Kavadias, S.; Michaelides, A.; Avouri, M.; Kalamara, C.; Stringaris, K.

    2001-01-01

    The aim of this study was to examine the effectiveness of helical CT in the assessment of intraocular foreign bodies, evaluating two protocols with different collimation. We performed helical-CT studies in 30 patients. Fifteen patients were examined with 1.5-mm collimation and the other 15 patients with 3.0-mm collimation. All other imaging parameters were identical in both protocols. Multiplanar images were reconstructed. The examinations were reviewed for presence, localization and size of intraocular foreign bodies. We compare our results with the surgical data. We estimate the required examination time. In the first group (collimation 1.5 mm) an intraorbital foreign body was detected in 8 of 15 patients. In 3 of 8 patients an intraocular foreign body (all were metallic) was detected. In the second group (collimation 3.0 mm) an intraorbital foreign body was detected in 9 of 15 patients. In 8 of 9 patients an intraocular foreign body (all were metallic) was detected. Our results were confirmed by surgery in all cases. Examination time was 36 s in the first group and 18 s in the second group. Computed tomography should be considered the imaging modality of choice in the assessment of metallic intraocular foreign bodies and 3.0-mm collimation is optional, because of reduced examination time and radiation exposure. (orig.)

  12. The significance of multi-slice helical CT multiplanar reconstruction in the diagnoses of laryngeal carcinoma

    International Nuclear Information System (INIS)

    Li Lin; Luo Dehong; Zhou Chunwu; Zhao Xinming; Jiang Liming; Huang Yao; Jiang Lingxia; Li Jing; Wu Ning

    2006-01-01

    Objective: To evaluate the significance of multi-slice helical CT with multiplanar reconstruction in laryngeal carcinoma. Methods: Thirty-five patients with laryngeal carcinoma were studied by helical CT, MPR were subsequently done. The lesion extent of the axial image findings, MPR findings and the combined image findings were compared with the pathological results respectively. The data were statistically analyzed. Results: In the evaluation of the anterior commissure, the axial image findings, MPR findings and the combined image findings were 82.9%, 68.6% and 91.4% in accuracy respectively, the results were statistically different (P 0.05). The combined images were superior to the axial images and the MPR images in sensitivity, specificity and accuracy of the lesion extent. Conclusion: The axial images could show the shape, size, extension of the tumor and the lymphadenopathy, MPR images displayed the shape, size and extension roundly and directly, they were the supplement for the axial images. Axial images combined with MPR could improve the accuracy in the diagnoses of laryngeal carcinoma. (authors)

  13. Anterior glenoid rim fracture: the value of helical CT with threedimensional reconstruction and electronic humeral disarticulation

    Directory of Open Access Journals (Sweden)

    Heverton César de Oliveira

    2003-06-01

    Full Text Available Objectives: To show a new three-dimensional reconstructiontechnique based on helical computed tomography images withelectronic humeral disarticulation in anterior glenoid rim fractures,correlating the anatomic specimen with simulation of an anteriorglenoid rim fracture, as well as evaluating the extension of thefracture, the bone fragment position and distance in relation to theglenoid cavity in six patients. Methods: One scapula and onehumerus with no signs of fracture or congenital malformationswere placed in anatomical position using an adhesive tape aftersimulating an anterior glenoid rim fracture made by an osteotome.Helical CT imaging was acquired and three-dimensionalreconstructions were made based on these images, with andwithout electronic humeral disarticulation. The bone fragment waslocated, measured and its position in relation to the glenoid cavitywas assessed. Six patients with anterior glenoid rim fracture weresubmitted to CT of the shoulder using the same parameters asthose applied to the anatomic specimen. Results: In the anatomicspecimen and in all six patients the bone fragment was clearlydemonstrated; bone fragment measurements in the anatomicspecimen and in three-dimensional reconstructions wereequivalent. The fragment was better demonstrated in the imagestaken with electronic humeral disarticulation, particularly in thefrontal view of the glenoid cavity as observed in all six patients.Conclusion: We concluded that our experiment with the anatomicspecimen and the study of six patients allow us to state that thistechnique is safe and accurate to demonstrate the extension, sizeand location of the bone fragment in anterior glenoid rim fractures,and it provides essential elements for therapeutic planning.

  14. The efficacy of low-dose helical CT screening as an option for health examination

    International Nuclear Information System (INIS)

    Kishi, Kazuma; Hara, Shigeko; Kurosaki, Atsuko; Fujii, Takeshi; Yoshimura, Kunihiko

    2007-01-01

    We retrospectively evaluated the results of low-dose helical CT screening as an option for health examinations. From November 2002 to October 2005, CT screening was performed in 2,306 individuals (men 1,766, women 540, mean age 56.1 years). Among them, 71 individuals (3.1%) were diagnosed as having active thoracic diseases consisting of 14 neoplasms and 57 non-neoplastic diseases. Of 14 patients with neoplastic lesions, 13 had lung cancer, 1 of whom had double primary lung cancer, and 1 had atypical adenomatous hyperplasia. The mean diameter of the 14 lung cancers was 14.4 mm. The histology of these lesions was adenocarcinoma in 13 and squamous cell carcinoma in 1. The pathological stage was IA in 12 patients and IIA in 1. All patients underwent surgical resection. On the other hand, emphysema was diagnosed in 40 asymptomatic individuals based on CT and spirometry, and smoking cessation was strongly implemented for those who were current smokers. CT screening is useful for detecting not only early lung cancer but also non-neoplastic lung diseases. (author)

  15. Diagnosis of aortic interruption by CT angiography

    International Nuclear Information System (INIS)

    Shirani, Shapour; Soleymanzadeh, Maryam

    2013-01-01

    Interrupted aortic arch (IAA) is a rare congenital malformation of the aortic arch, which might be accompanied with other coexisting cardiovascular anomalies. Many cases with IAA are diagnosed at their neonatal and newborn period but in rare cases the diagnosis is not established until adulthood. The patients may have no clinical symptoms but the signs of heart failure will gradually appear and may cause death. The development of imaging methods such as computed tomography (CT) and magnetic resonance (MR) imaging has dramatically changed the diagnostics. Here we report a 20-year-old young man with IAA associated with sinus venosus atrial septal defect (SVD) and partial anomalous pulmonary venous connection (PAPVC) referred to our hospital

  16. Maximum-intensity-projection CT angiography for evaluating head and neck tumors. Usefulness of helical CT and auto bone masking method

    International Nuclear Information System (INIS)

    Sakai, Osamu; Nakashima, Noriko; Ogawa, Chiaki; Shen, Yun; Takata, Yasunori; Azemoto, Shougo.

    1994-01-01

    Angiographic images of 10 adult patients with head and neck tumors were obtained by helical computed tomography (CT) using maximum intensity projection (MIP). In all cases, the vasculature of the head and neck region was directly demonstrated. In the head and neck, bone masking is a more important problem than in other regions. We developed an effective automatic bone masking method (ABM) using 2D/3D connectivity. Helical CT angiography with MIP and ABM provided accurate anatomic depiction, and was considered to be helpful in preoperative evaluation of head and neck tumors. (author)

  17. Helical CT findings of gastric wall thickening by peptic ulcer : compared with gastric adenocarcinoma with ulcer

    International Nuclear Information System (INIS)

    Jung, Won Jung; Choi, Jong Chul; Seo, Keum Soo; Koo, Bon Sik; Park, Byeong Ho; Kim, Chung Ku; Lee, Ki Nam; Nam, Kyung Jin

    2000-01-01

    To compare on the basis of helical CT findings gastric wall thickening of peptic gastric ulcer with that of gastric adenocarcinoma with ulcer. Thirty-eight patients with pathologically proven gastric lesion (17 cases of peptic ulcer and 21 cases of ulcerative or ulceroinfiltrative gastric cancer (Borrman type II, III) underwent helical CT, and the findings were retrospectively reviewed in terms of maximum abnormal wall thickness, preservation of the inner enhancing layer, the presence three discriminate layers of gastric wall, and enhancement pattern. The enhancement pattern of abnormally thick wall was compared with that of the portal phase of back muscle, and was defined as low, iso, or high. The Chi-square test and Student t test were used for statistical analysis. In cases of peptic ulcer and gastric cancer with ulceration, maximum abnormal wall thickness was 7-30 (mean, 16.1)mm, and 11-33 (mean, 21.8)mm, respectively. The inner enhancing layer was preserved in 15 of 17 patients (88.2%) and one of 21 (4.8%); three discriminate layers of gastric wall were observed in 8 of 17 patients (47.0%), and one of 21 (4.8%). The enhancement pattern was low in 12 of 17 patients (70.5%), and 3 of 21 (14.3%); iso in 4 of 17 (23.5%), and 4 of 21 (19.0%), and high in one of 17 (5.9%), and 14 of 21 (66.7%). All figures refer, respectively, to the two distinct conditions. In terms of preservation of the inner enhancing layer, three discriminate layers of gastric wall, and a low enhancement pattern, there were statistically significant differences between peptic ulcer and gastric adenocarcinoma with ulcer. Where the enhancement was high, however, the statistically significant difference between the two conditions was even greater. There was no statistically significant difference in terms of gastric wall thickness or iso-attenuation of thickened gastric. Helical CT findings of gastric wall thickening, preservation of the inner enhancing layer, and three discriminate layers of

  18. Helical CT findings of gastric wall thickening by peptic ulcer : compared with gastric adenocarcinoma with ulcer

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Won Jung; Choi, Jong Chul; Seo, Keum Soo; Koo, Bon Sik; Park, Byeong Ho; Kim, Chung Ku; Lee, Ki Nam; Nam, Kyung Jin [College of Medicine, Dong A University, Pusan (Korea, Republic of)

    2000-02-01

    To compare on the basis of helical CT findings gastric wall thickening of peptic gastric ulcer with that of gastric adenocarcinoma with ulcer. Thirty-eight patients with pathologically proven gastric lesion (17 cases of peptic ulcer and 21 cases of ulcerative or ulceroinfiltrative gastric cancer (Borrman type II, III)) underwent helical CT, and the findings were retrospectively reviewed in terms of maximum abnormal wall thickness, preservation of the inner enhancing layer, the presence three discriminate layers of gastric wall, and enhancement pattern. The enhancement pattern of abnormally thick wall was compared with that of the portal phase of back muscle, and was defined as low, iso, or high. The Chi-square test and Student t test were used for statistical analysis. In cases of peptic ulcer and gastric cancer with ulceration, maximum abnormal wall thickness was 7-30 (mean, 16.1)mm, and 11-33 (mean, 21.8)mm, respectively. The inner enhancing layer was preserved in 15 of 17 patients (88.2%) and one of 21 (4.8%); three discriminate layers of gastric wall were observed in 8 of 17 patients (47.0%), and one of 21 (4.8%). The enhancement pattern was low in 12 of 17 patients (70.5%), and 3 of 21 (14.3%); iso in 4 of 17 (23.5%), and 4 of 21 (19.0%), and high in one of 17 (5.9%), and 14 of 21 (66.7%). All figures refer, respectively, to the two distinct conditions. In terms of preservation of the inner enhancing layer, three discriminate layers of gastric wall, and a low enhancement pattern, there were statistically significant differences between peptic ulcer and gastric adenocarcinoma with ulcer. Where the enhancement was high, however, the statistically significant difference between the two conditions was even greater. There was no statistically significant difference in terms of gastric wall thickness or iso-attenuation of thickened gastric. Helical CT findings of gastric wall thickening, preservation of the inner enhancing layer, and three discriminate layers of

  19. Angiomyolipoma with minimal fat: Differentiation from papillary renal cell carcinoma by helical CT

    International Nuclear Information System (INIS)

    Zhang, Y.-Y.; Luo, S.; Liu, Y.; Xu, R.-T.

    2013-01-01

    Aim: To evaluate whether helical computed tomography (CT) images can be used to differentiate angiomyolipomas (AMLs) with minimal fat from papillary renal cell carcinomas (PRCCs) based on their morphological characteristics and enhancement features. Materials and methods: This retrospective study was approved by the institutional review board. Informed consent was waived. Forty-four patients (21 with AMLs with minimal fat and 23 with PRCCs) who underwent enhanced helical CT before total or partial nephrectomy were included. Two radiologists, who were blinded to the histopathology results, read the CT images and recorded the attenuation value, morphological characteristics, and enhancement features of the tumours, which were subsequently evaluated. An independent samples t-test, χ 2 test, and rank sum test were performed between the tumours. The predictive value of a CT finding was determined by multivariate logistic regression analysis. Results: AML with minimal fat had an apparent female prevalence (p < 0.01). Intra-tumoural vessels were noted in 11 cases of AML with minimal fat and three PRCC cases (p < 0.01). The unenhanced attenuation characteristic was significantly different between the two diseases (p < 0.001). The absolute attenuation values (AAVs) and the corrected attenuation values (CAVs) of the AML with minimal fat group of unenhanced and two phases of enhanced images were greater compared with that of the PRCC group (p < 0.05). After contrast medium injection, the tumour enhancement value (TEV) of the AML with minimal fat group in the corticomedullary phase was greater than that of the PRCC group (p < 0.01). Most cases of both tumour types demonstrated early enhancement characteristics; the enhancement value of the AML with minimal fat group was greater compared with that of the PRCC group (p < 0.01). The unenhanced attenuation characteristic, intra-tumoural vessels, and CAVs of unenhanced and early excretory phase scans were valuable parameters to

  20. COMPUTED TOMOGRAPHY DOSE INDEX MEASUREMENT FOR Hi-ART MEGAVOLTAGE HELICAL CT.

    Science.gov (United States)

    Liu, Minglu; Wang, Yunlai; Liao, Xiongfei

    2016-11-01

    On-line megavoltage computed tomography (MVCT) images are used to verify patient daily set-up in Hi-ART helical TomoTherapy unit. To evaluate the patient dose from MVCT scanning in image guidance, weighted computed tomography (CT) dose index (CTDI w ) was measured with PTW TM30009 CT pencil chamber in head and body phantoms for slice thicknesses of 2, 4 and 6 mm with different scan lengths. Dose length products (DLPs) were subsequently calculated. The CTDI w and DLP were compared with XVI kV CBCT and Brilliance simulator CT for routine clinical protocols. It was shown that CTDI and DLP had close relationship with the slice thickness and the scan length. The dose distribution in the transversal plane was very inhomogeneous due to the attenuation of the couch. Patient dose from MVCT was lower than XVI CBCT for the head scan, while larger for body scan. CTDI w , which is measured easily and reproducibly, can be used to assess the patient dose in MVCT. Regular measurement should be performed in QA & QC programmes. Appropriate slice thickness and scan range should be chosen to reduce the patient dose. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Prenatal diagnosis of fetal skeletal dysplasia with 3D CT

    International Nuclear Information System (INIS)

    Miyazaki, Osamu; Horiuchi, Tetsuya; Nishimura, Gen; Sago, Haruhiko; Hayashi, Satoshi; Kosaki, Rika

    2012-01-01

    Clinical use of 3D CT for fetal skeletal malformations is controversial. The purpose of this study was to evaluate the efficacy of fetal 3D CT using three protocols with different radiation doses and through comparing findings between fetal CT and conventional postnatal radiographic skeletal survey. Seventeen fetuses underwent CT for suspected skeletal dysplasia. A relay of three CT protocols with stepwise dose-reduction were used over the study period. The concordance between the CT diagnosis and the final diagnosis was assessed. Ninety-three radiological findings identifiable on radiographs were compared with CT. Fetal CT provided the correct diagnosis in all 17 fetuses, the detectability rate of cardinal findings was 93.5 %. In 59 % of the fetuses an US-based diagnosis was changed prenatally due to CT findings. The estimated fetal radiation dose in the final protocol was 3.4 mSv (50 %) of the initial protocol, and this dose reduction did not result in degraded image quality. The capability of fetal CT to delineate the skeleton was almost the same as that of postnatal skeletal survey. The perinatal management was altered due to these more specific CT findings, which aided in counseling and in the management of the pregnancy. (orig.)

  2. Prenatal diagnosis of fetal skeletal dysplasia with 3D CT

    Energy Technology Data Exchange (ETDEWEB)

    Miyazaki, Osamu; Horiuchi, Tetsuya [National Center for Child Health and Development, Department of Radiology, Seatagaya-ku, Tokyo (Japan); Nishimura, Gen [Tokyo Metropolitan Children' s Medical Center, Department of Pediatric Imaging, Fuchu-shi, Tokyo (Japan); Sago, Haruhiko; Hayashi, Satoshi [National Center for Child Health and Development, Department of Perinatal Medicine and Maternal Care, Seatagaya-ku, Tokyo (Japan); Kosaki, Rika [National Center for Child Health and Development, Department of Strategic Medicine, Division of Clinical Genetics and Molecular Medicine, Seatagaya-ku, Tokyo (Japan)

    2012-07-15

    Clinical use of 3D CT for fetal skeletal malformations is controversial. The purpose of this study was to evaluate the efficacy of fetal 3D CT using three protocols with different radiation doses and through comparing findings between fetal CT and conventional postnatal radiographic skeletal survey. Seventeen fetuses underwent CT for suspected skeletal dysplasia. A relay of three CT protocols with stepwise dose-reduction were used over the study period. The concordance between the CT diagnosis and the final diagnosis was assessed. Ninety-three radiological findings identifiable on radiographs were compared with CT. Fetal CT provided the correct diagnosis in all 17 fetuses, the detectability rate of cardinal findings was 93.5 %. In 59 % of the fetuses an US-based diagnosis was changed prenatally due to CT findings. The estimated fetal radiation dose in the final protocol was 3.4 mSv (50 %) of the initial protocol, and this dose reduction did not result in degraded image quality. The capability of fetal CT to delineate the skeleton was almost the same as that of postnatal skeletal survey. The perinatal management was altered due to these more specific CT findings, which aided in counseling and in the management of the pregnancy. (orig.)

  3. Implementation techniques and acceleration of DBPF reconstruction algorithm based on GPGPU for helical cone beam CT

    International Nuclear Information System (INIS)

    Shen Le; Xing Yuxiang

    2010-01-01

    The derivative back-projection filtered algorithm for a helical cone-beam CT is a newly developed exact reconstruction method. Due to its large computational complexity, the reconstruction is rather slow for practical use. General purpose graphic processing unit (GPGPU) is an SIMD paralleled hardware architecture with powerful float-point operation capacity. In this paper,we propose a new method for PI-line choice and sampling grid, and a paralleled PI-line reconstruction algorithm implemented on NVIDIA's Compute Unified Device Architecture (CUDA). Numerical simulation studies are carried out to validate our method. Compared with conventional CPU implementation, the CUDA accelerated method provides images of the same quality with a speedup factor of 318. Optimization strategies for the GPU acceleration are presented. Finally, influence of the parameters of the PI-line samples on the reconstruction speed and image quality is discussed. (authors)

  4. CT diagnosis of acute spinal injury

    International Nuclear Information System (INIS)

    Ohhama, Mitsuru; Niimiya, Hikosuke; Kimura, Ko; Yamazaki, Gyoji; Nasu, Yoshiro; Shioya, Akihide

    1982-01-01

    CT pictures of 22 acute spinal injuries with damage of the spinal cord were evaluated. In the cases of spinal cord damage with bone injury, changes in the vertebral canal were fully observed by CT. In some of spinal cord damages without bone injury, narrowing of the vertebral canal was demonstrated by CT combined with CT myelography and reconstruction. Evaluation of CT number showed a high density area in damaged spinal cord in some cases. CT was thus considered to be useful as an adjunct diagnostic aid. (Ueda, J.)

  5. Budd-Chiari syndrome: dynamic enhancement findings with multi-slice helical CT and CT angiography analysis

    International Nuclear Information System (INIS)

    Meng Xiaochun; Shan Hong; Zhu Kangshun; Xu Chuan; Zhang Jiansheng; Liu Lingyun; Ye Binbin

    2005-01-01

    Objective: To investigate the dynamic enhancement regulations of liver and their mechanism in Budd-Chiari syndrome (BCS) by using multi-slice CT and evaluate the value of CT angiography in the diagnosis of BCS. Methods: 28 cases with BCS confirmed by digital subtraction angiography (DSA) were retrospectively analyzed. All patients underwent dynamic enhancement examinations with multi-slice CT within 1 week before DSA. The relevant vessels were reconstructed respectively with MIP, VR and MPR. Compared with the results of DSA, we analyzed the dynamic enhancement regulations of liver in BCS, estimated the value of dynamic enhancement CT exams and CTA techniques in judging the obstruction level and showing collateral vessels. Results: Of all 28 cases, CT correctly showed the obstruction level in 26 cases, and 2 had incorrect results which proved to be membranous obstruction of the inferior vena cava superior to diaphragm. In 22 cases with hepatic vein obstructions, hepatic parenchyma displayed typical patchy enhancement in 19, atypical patchy enhancement in 3.8 cases among these showed benign nodules. Simultaneously, CT showed stenosis and rigidity of portal vein branches in 20, enlargement of hepatic artery in 14, hepatic collateral vessels in 20 out of 22 cases. In 6 cases with simple obstruction of inferior vena cava, hepatic changes were not found. Collateral circulations in or out of liver corresponded to the obstruction level. Conclusion: Dynamic enhancement examinations with multi-slice CT can correctly reflect the hepatic hemodynamic changes. Transverse images, combined with CTA, can explicitly display the obstruction level of vascular lesions and collateral circulations in BCS. (authors)

  6. Approximations of noise covariance in multi-slice helical CT scans: impact on lung nodule size estimation.

    Science.gov (United States)

    Zeng, Rongping; Petrick, Nicholas; Gavrielides, Marios A; Myers, Kyle J

    2011-10-07

    Multi-slice computed tomography (MSCT) scanners have become popular volumetric imaging tools. Deterministic and random properties of the resulting CT scans have been studied in the literature. Due to the large number of voxels in the three-dimensional (3D) volumetric dataset, full characterization of the noise covariance in MSCT scans is difficult to tackle. However, as usage of such datasets for quantitative disease diagnosis grows, so does the importance of understanding the noise properties because of their effect on the accuracy of the clinical outcome. The goal of this work is to study noise covariance in the helical MSCT volumetric dataset. We explore possible approximations to the noise covariance matrix with reduced degrees of freedom, including voxel-based variance, one-dimensional (1D) correlation, two-dimensional (2D) in-plane correlation and the noise power spectrum (NPS). We further examine the effect of various noise covariance models on the accuracy of a prewhitening matched filter nodule size estimation strategy. Our simulation results suggest that the 1D longitudinal, 2D in-plane and NPS prewhitening approaches can improve the performance of nodule size estimation algorithms. When taking into account computational costs in determining noise characterizations, the NPS model may be the most efficient approximation to the MSCT noise covariance matrix.

  7. Usefulness of multiplanar reformatted images of multi-detector row helical CT in assessment of biliary stent patency

    International Nuclear Information System (INIS)

    Kim, Soo Jin; Kim, Suk; Kim, Chang Won; Lee, Jun Woo; Lee, Tae Hong; Choo, Ki Seok; Koo, Young Baek; Moon, Tae Yong; Lee, Suk Hong

    2004-01-01

    To evaluate the usefulness of multi-detector row helical CT (MDCT), multiplanar reformatted images for the noninvasive assessment of biliary stent patency, and for the planning for management in patients with a sele-expandable metallic stent due to malignant biliary obstruction. Among 90 consecutive patients, from August 1999 to July 2003, 26 cases in 23 patients with malignant biliary obstruction who underwent self-expandable metaIlic stent insertion in the biliary system and percutaneous transhepatic biliary drainage within 7 days after CT were enrolled in this study. On CT images, the complete and functional obstruction of the stent and the precise level of obstruction were evaluated. The presence of an enhancing intraluminal mass or wall thickening around stent was determined, and the causes of obstruction were evaluated. These findings were then compared with percutaneous transhepatic cholangiography. Multi-detector row helical CT correctly demonstrated the patency of a stent in 24 cases (92.3%). It was adequate in helping to depict the precise level of stent occlusion in 23 cases (88.5%). Multi-detector row helical CT also revealed the extent of tumor that represented as an enhancing intraluminal mass or wall thickening around the stent in 23 cases, and this was represented as complete obstruction on percutaneous transhepatic cholangiography. In the case of functional obstruction, MDCT predicted the possible cause of the obstruction. Multiplanar reformatted images of multi-detector row helical CT is a useful imaging modality for the noninvasive assessment of stent patency and the precise level of obstruction when stent obstruction is suspected in the patients with self-expandable metallic stent due to malignant biliary obstruction. It can also predict the possible cause of the obstruction and allows adequate planning for the medical management of such cases

  8. Usefulness of multiplanar reformatted images of multi-detector row helical CT in assessment of biliary stent patency

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Soo Jin; Kim, Suk; Kim, Chang Won; Lee, Jun Woo; Lee, Tae Hong; Choo, Ki Seok; Koo, Young Baek; Moon, Tae Yong; Lee, Suk Hong [Pusan National Univ. Hospital, Busan (Korea, Republic of)

    2004-08-01

    To evaluate the usefulness of multi-detector row helical CT (MDCT), multiplanar reformatted images for the noninvasive assessment of biliary stent patency, and for the planning for management in patients with a sele-expandable metallic stent due to malignant biliary obstruction. Among 90 consecutive patients, from August 1999 to July 2003, 26 cases in 23 patients with malignant biliary obstruction who underwent self-expandable metaIlic stent insertion in the biliary system and percutaneous transhepatic biliary drainage within 7 days after CT were enrolled in this study. On CT images, the complete and functional obstruction of the stent and the precise level of obstruction were evaluated. The presence of an enhancing intraluminal mass or wall thickening around stent was determined, and the causes of obstruction were evaluated. These findings were then compared with percutaneous transhepatic cholangiography. Multi-detector row helical CT correctly demonstrated the patency of a stent in 24 cases (92.3%). It was adequate in helping to depict the precise level of stent occlusion in 23 cases (88.5%). Multi-detector row helical CT also revealed the extent of tumor that represented as an enhancing intraluminal mass or wall thickening around the stent in 23 cases, and this was represented as complete obstruction on percutaneous transhepatic cholangiography. In the case of functional obstruction, MDCT predicted the possible cause of the obstruction. Multiplanar reformatted images of multi-detector row helical CT is a useful imaging modality for the noninvasive assessment of stent patency and the precise level of obstruction when stent obstruction is suspected in the patients with self-expandable metallic stent due to malignant biliary obstruction. It can also predict the possible cause of the obstruction and allows adequate planning for the medical management of such cases.

  9. Hereditary haemorrhagic telangiectasia: study of hepatic vascular alterations with multi-detector row helical CT and reconstruction programs

    International Nuclear Information System (INIS)

    Memeo, Maurizio; Stabile Ianora, Amato Antonio; Scaldapane, Arnaldo; Rotondo, Antonio; Angelelli, Giuseppe; Suppressa, Patrizia; Cirulli, Anna; Sabba', Carlo

    2005-01-01

    Purpose: To evaluate hepatic alterations in patients affected by Hereditary Haemorrhagic Telangiectasia (HHT) by using multidetector row helical CT (MDCT) and new reconstruction programs. Materials and methods: An MDCT multiphasic study of the liver was performed in 105 consecutive patients: 89 considered to be affected by HHT and 16 with suspicion of disease alone. The scan delay was determined by using a test bolus of contrast material. The CT examination was performed with a triphasic technique (double arterial phase and portal venous phase). multiplanar and angiographic reconstructions were then obtained, and the images checked for the presence of shunts, hepatic perfusion disorders, vascular lesions (telangiectasis and large confluent vascular masses), indirect signs of portal hypertension, and anatomical vascular variants. Results: Hepatic vascular alterations were found in 78/105 cases (67/89) patients affected by HHT and 11/16 patients with clinical suspicion alone). Therefore HHT diagnosis was excluded in 5 patients. 78/100 (78%) patients with HHT had intrahepatic vascular alterations: arterioportal shunts in 40/78 (51.2%) arteriosystemic shunts in 16/78 (20.5%) and both shunt types in 22/78 (28.3%). Intraparenchymal perfusion disorders were found in 46/78 (58.9%) patients. Telangiectasis were recognised in 50/78 (64.1%) patients. Large confluent vascular masses (LCVMs) were identified in 20/78 (25.6%) patients. indirect signs of portal hypertension were found in 46/78 (58.9%) cases. Variant hepatic arterial anatomy was present in 38/100 cases (38%). Conclusions: Multiphasic MDCT and the new reconstruction programs enable the identification and characterisation of the complex vascular alterations typical of HHT [it

  10. Value of CT in the diagnosis of pseudomembranous colitis

    International Nuclear Information System (INIS)

    Fishman, E.K.; Merine, D.S.; Kuhlman, J.E.; Jones, B.

    1989-01-01

    With the increasing use of Ct as a primary imaging modality in the patient with abdominal distress, it is not surprising the CT may be the initial study to suggest the diagnosis of pseudomembranous colitis. The authors reviewed the CT scans in 16 patients with proved pseudomembranous colitis. In 12 of these cases, the diagnosis was not considered prior to CT. The CT findings included wall thickening (average, 18 mm), definite ulcerations (11 cases), ascites (two cases), and pseudoperforation (three cases). The pseudoperforation is caused by the trapping of contrast material within the large ulcerated mucosal folds and can simulate contrast extravasation. The various CT appearances of pseudomembranous colitis are addressed, as well as the potential difficulty in distinguishing it from other types of colitis

  11. Dynamic evaluation of pelvic floor reconstructive surgery using radiopaque meshes and three-dimensional helical CT

    Directory of Open Access Journals (Sweden)

    Paulo Palma

    2010-04-01

    Full Text Available PURPOSE: This prospective study was performed to achieve visualization of the reestablishment of anatomy after reconstructive surgery in the different pelvic compartments with non-absorbable radiopaque meshes, providing valuable anatomic information for surgeons implanting meshes. MATERIALS AND METHODS: A total of 30 female patients with stress urinary incontinence (SUI, anterior and posterior vaginal wall prolapse, or both underwent surgical repair using radiopaque meshes after written informed consent. Patients with SUI underwent five different surgeries. Patients with anterior vaginal prolapse underwent a procedure using a combined pre-pubic and transobturator mesh, and those with posterior vaginal prolapse underwent posterior slingplasty. Three-dimensional reconstruction using helical CT was performed four weeks postoperatively. RESULTS: In all cases, the mesh was clearly visualized. Transobturator slings were shown at the midurethra, and the anchoring tails perforated the obturator foramen at the safety region. Mini-slings were in the proper place, and computed angiography revealed that the anchoring system was away from the obturator vessels. In patients undergoing procedure for anterior vaginal prolapse, both pre-pubic armpit and obturator slings were clearly seen and the mesh was in the proper position, supporting the bladder base and occluding the distal part of the urogenital hiatus. Transcoccygeal sacropexy revealed indirectly a well-supported "neo rectovaginal fascia" and the anchoring tails at the level of ischial spines. CONCLUSION: Three-dimensional helical tomography images of the female pelvis using radiopaque meshes have a potential role in improving our understanding of pelvic floor reconstructive surgeries. These radiopaque meshes might be the basis of a new investigative methodology.

  12. Multidetector helical CT plus superparamagnetic iron oxide-enhanced MR imaging for focal hepatic lesions in cirrhotic liver: A comparison with multi-phase CT during hepatic arteriography

    International Nuclear Information System (INIS)

    Yukisawa, Seigo; Okugawa, Hidehiro; Masuya, Yoshio; Okabe, Shinichirou; Fukuda, Hiroyuki; Yoshikawa, Masaharu; Ebara, Masaaki; Saisho, Hiromitsu

    2007-01-01

    The aim of this study was to evaluate multidetector helical computed tomography (MDCT), superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) imaging, and CT arterial portography (CTAP) and CT during hepatic arteriography (CTHA) for the detection and diagnosis of hepatocellular carcinomas (HCC). This included visual correlations of MDCT and SPIO-MR imaging in the detection of HCC using receiver operating characteristic (ROC) analysis. Twenty-five patients with 57 nodular HCCs were retrospectively analyzed. A total of 200 segments, including 49 segments with 57 HCCs, were reviewed independently by three observers. Each observer read four sets of images (set 1, MDCT; set 2, unenhanced and SPIO-enhanced MR images; set 3, combined MDCT and SPIO-enhanced MR images; set 4, combined CTAP and CTHA). The mean Az values representing the diagnostic accuracy for HCCs of sets 1, 2, 3, and 4 were 0.777, 0.814, 0.849, and 0.911, respectively, and there was no significant difference between sets 3 and 4. The sensitivity of set 4 was significantly higher than those of set 3 for all the lesions and for lesions 10 mm or smaller (p < 0.05); however, for lesions larger than 10 mm, the sensitivities of the two sets were similar. No significant difference in positive predictive value and specificity was observed between set 3 and set 4. Combined MDCT and SPIO-enhanced MR imaging may obviate the need for more invasive CTAP and CTHA for the pre-therapeutic evaluation of patients with HCC more than 10 mm

  13. Blunt trauma to the gastrointestinal tract and mesentery: is there a role for helical CT in the decision-making process?

    International Nuclear Information System (INIS)

    Scaglione, Mariano; de Lutio di Castelguidone, Elisabetta; Scialpi, Michele; Merola, Stefanella; Diettrich, Andrea Irma; Lombardo, Patrizia; Romano, Luigia; Grassi, Roberto

    2004-01-01

    The CT diagnosis of bowel and mesenteric injuries is difficult and warrants optimal technique and skilled interpretation. We retrospectively reviewed 36 consecutive patients with blunt traumatic injuries to the bowel and mesentery at our regional level I trauma center during the past 3 years. Physical examination, laboratory, Computed tomographic (CT), and intraoperative findings were compared. Surgically proven bowel injuries (13 cases) occurred in the duodenum (three cases), ileum (two cases), jejunum (two cases), colon (three cases), and stomach (three cases). CT findings considered specific of bowel rupture were observed in 5/13 patients including: extraluminal oral contrast or luminal content extravasation (four cases) and discontinuity of hollow viscus wall (one case). In the remaining 8/13 CT findings considered suggestive of bowel injury consisted of: pneumoperitoneum (six), gas bubbles close to the injured hollow viscus (three), thickened (>4-5 mm) bowel wall (five), bowel wall hematoma (three), intraperitoneal fluid of unknown source (three). Mesenteric injury (23 cases) were surgically observed at the level of the mesenteric vessels (17 cases), legament of Treitz (two cases), gastro-duodenal artery (one case), transverse (one case) and sigmoid mesocolon (one case). CT finding considered specific of mesenteric laceration was active extravasation of contrast material from the mesenteric vessels (10 cases). CT findings suggestive of mesenteric injury (13 cases) consisted of: mesenteric hematoma (five) and/or high attenuation fluid collections, within the mesenteric root (eight) and folds (four). Helical CT is sensitive in the identification of bowel and mesenteric injury after blunt trauma providing a wide spectrum of findings. However, CT cannot be used as the sole indicator in cases with isolated thickened bowel wall, mesenteric hematoma, bowel hematoma, pneumoperitoneum or gas bubbles. Persistent, active extravasation of intravenous contrast medium from

  14. CT diagnosis of retroperitoneal gigantic liposarcoma

    International Nuclear Information System (INIS)

    Fang Wei; Zheng Zhaohua; Liao Zuyuan; Hu Yinsong

    2009-01-01

    Objective: To analyze CT manifestation of retroperitoneal gigantic liposaxcoma and to improve the image understanding. Methods: Five cases of retroperitoneal gigantic liposarcoma confirmed by surgery and pathology in our hospital were collected. Plain and enhanced CT scan were performed. Results: Of five cases, one was substantive, two was pseudocyst and two was mixed tumor. Several patterns of enhancement such as strip, floccule, irregular patchy or nodular enhancement were revealed inside the lesions on enhanced CT scan. And strip-form of high density enhancement was a typical type. Conclusion: CT examination could determine the tumor's location, size and density, together with the relationship to adjacent organizations CT scan is an important method in diagnosing retroperitoneal gigantic liposarcoma. (authors)

  15. Prospectively ECG-triggered sequential dual-source coronary CT angiography in patients with atrial fibrillation: comparison with retrospectively ECG-gated helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Lei; Yang, Lin; Zhang, Zhaoqi [Capital Medical University, Department of Radiology, Beijing Anzhen Hospital, Beijing (China); Wang, Yining; Jin, Zhengyu [Chinese Academy of Medical Sciences, Department of Radiology, Peking Union Medical College Hospital, Beijing (China); Zhang, Longjiang; Lu, Guangming [Nanjing University, Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing, Jiangsu (China)

    2013-07-15

    To investigate the feasibility of applying prospectively ECG-triggered sequential coronary CT angiography (CCTA) to patients with atrial fibrillation (AF) and evaluate the image quality and radiation dose compared with a retrospectively ECG-gated helical protocol. 100 patients with persistent AF were enrolled. Fifty patients were randomly assigned to a prospective protocol and the other patients to a retrospective protocol using a second-generation dual-source CT (DS-CT). Image quality was evaluated using a four-point grading scale (1 = excellent, 2 = good, 3 = moderate, 4 = poor) by two reviewers on a per-segment basis. The coronary artery segments were considered non-diagnostic with a quality score of 4. The radiation dose was evaluated. Diagnostic segment rate in the prospective group was 99.4 % (642/646 segments), while that in the retrospective group was 96.5 % (604/626 segments) (P < 0.001). Effective dose was 4.29 {+-} 1.86 and 11.95 {+-} 5.34 mSv for each of the two protocols (P < 0.001), which was a 64 % reduction in the radiation dose for prospective sequential imaging compared with retrospective helical imaging. In AF patients, prospectively ECG-triggered sequential CCTA is feasible using second-generation DS-CT and can decrease >60 % radiation exposure compared with retrospectively ECG-gated helical imaging while improving diagnostic image quality. (orig.)

  16. CT diagnosis of hyperdense intracranial neoplasms. Review of the literature

    International Nuclear Information System (INIS)

    Ishikura, Reiichi; Ando, Kumiko; Tominaga, Satoru; Nakao, Norio; Ikeda, Jouta; Takemura, Yuriko; Morikawa, Tsutomu

    1999-01-01

    In contrast to typical astrocytic tumors that show hypodense areas on computed tomographic images, some intracranial tumors show hyperdense areas on CT images. The major reasons for hyperdensity on CT images are hypercellular lesions, intratumoral calcification, and intratumoral hemorrhage. Malignant lymphomas, germinomas, and medulloblastomas show homogenous hyperdensity on CT images because of their hypercellularity. Tumorous lesions such as subependymal giant cell astrocytomas, oligodendrogliomas, ependymomas, central neurocytomas, craniopharyngiomas, and meningiomas often present with hyperdense calcified lesions on CT images. Intratumoral hemorrhage also causes hyperdensity on CT images, and is often associated with metastatic brain tumors, glioblastomas, pituitary adenomas, and rarely with any of the other intracranial tumors. Although magnetic resonance imaging is now the major diagnostic tool for diseases of the central nervous system, the first imaging studies for patients with neurologic symptoms are still CT scans. Hyperdense areas on CT images are a clue to making an accurate diagnosis of intracranial neoplasms. (author)

  17. CT diagnosis of intraperitoneal bladder rupture with blunt abdominal trauma

    International Nuclear Information System (INIS)

    Kong Fanbin

    2000-01-01

    Objective: To evaluate CT examination in the diagnosis of intraperitoneal bladder rupture (IPBR) caused by blunt abdominal trauma. Methods: All CT and clinical data of 9 patients with IPBR were reviewed retrospectively. Results: IPBR was detected on CT scans in all 9 patients. CT findings of IPBR included low -attenuation free intraperitoneal fluid collections in the lateral paravesical fossae, the pericolic space, the culde-sac of the pelvis, Morison's pouch, the peri-hepatic space, the perisplenic space and interspace of bowel loops in 9 cases with a lower CT density compared with pure blood. The disruption of the bladder wall was located by CT scan in 5 cases: high-attenuation bladder wall with focal defect in 3 cases and a tear drop-like deformity of the bladder in 2 cases. Other CT findings supporting the diagnosis of IPBR included an underfilled bladder in 8 cases, bladder contusion in 4 cases, and blood clots within the bladder in 6 cases. Conclusion: The presence of intraperitoneal fluid with a CT density less than that of pure blood strongly suggests extravasated urine in the trauma. Intraperitoneal and extraperitoneal rupture can be distinguished based on location of extravasated urine seen on CT scans. The precise localization of the ruptured bladder wall may be demonstrated by CT scan, which is valuable for surgical treatment

  18. Imaging skeletal anatomy of injured cervical spine specimens: comparison of single-slice vs multi-slice helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Obenauer, S.; Alamo, L.; Herold, T.; Funke, M.; Kopka, L.; Grabbe, E. [Department of Radiology, Georg August-University Goettingen, Robert-Koch-Strasse 40, 37075 Goettingen (Germany)

    2002-08-01

    Our objective was to compare a single-slice CT (SS-CT) scanner with a multi-slice CT (MS-CT) scanner in the depiction of osseous anatomic structures and fractures of the upper cervical spine. Two cervical spine specimens with artificial trauma were scanned with a SS-CT scanner (HighSpeed, CT/i, GE, Milwaukee, Wis.) by using various collimations (1, 3, 5 mm) and pitch factors (1, 1.5, 2, 3) and a four-slice helical CT scanner (LightSpeed, QX/i, GE, Milwaukee, Wis.) by using various table speeds ranging from 3.75 to 15 mm/rotation for a pitch of 0.75 and from 7.5 to 30 mm/rotation for a pitch of 1.5. Images were reconstructed with an interval of 1 mm. Sagittal and coronal multiplanar reconstructions of the primary and reconstructed data set were performed. For MS-CT a tube current resulting in equivalent image noise as with SS-CT was used. All images were judged by two observers using a 4-point scale. The best image quality for SS-CT was achieved with the smallest slice thickness (1 mm) and a pitch smaller than 2 resulting in a table speed of up to 2 mm per gantry rotation (4 points). A reduction of the slice thickness rather than of the table speed proved to be beneficial at MS-CT. Therefore, the optimal scan protocol in MS-CT included a slice thickness of 1.25 mm with a table speed of 7.5 mm/360 using a pitch of 1.5 (4 points), resulting in a faster scan time than when a pitch of 0.75 (4 points) was used. This study indicates that MS-CT could provide equivalent image quality at approximately four times the volume coverage speed of SS-CT. (orig.)

  19. CT diagnosis of acute appendicitis in children

    International Nuclear Information System (INIS)

    Kimura, Kenya; Matsuda, Masao; Iyomasa, Shinsuke

    2001-01-01

    Enhanced and 5 mm collimation CT was performed in patients suspected of having appendicitis. CT clearly showed the swollen appendix, appendolith, periappendiceal inflammation, fluid collection, and abscess in patients with phlegmonous or gangrenous appendicitis. These findings were not observed in patients with catarrhal appendicitis or normal appendix. To decide on operative indications of acute appendicitis in children, the following findings are important: the diameter of the swollen appendix exceeds 8 mm; on appendolith is observed; periappendiceal fluid collection and abscess is observed. We emphasize that enhanced CT is useful to diagnose appendicitis which is not obvious with US. (author)

  20. Multislice Helical CT Angiography in Diagnostic of Intracranial and Extracranial Arterial Dissection

    International Nuclear Information System (INIS)

    Radzina, M.; Krumina, G.; Pupols, J.

    2007-01-01

    complete information about arterial extracranial and intracranial vascular system. CTA is highly informative in characterization of dissection site and morphology, also diagnostic of combined brain pathology. Appropriate quality CTA requires high capacity: at least 16 slice helical CT equipment that provides quick examination with wide range of post processing possibilities. Non enhanced brain CT is recommended before CTA, to specify cerebral structural changes and to identify vascular calcified plaques. Indications for intracranial CTA: subarachnoidal hemorrhage, intracerebral hematoma, intraventricular hemorrhage, cerebral infarction; outpatient praxis: stenoses, aneurysms, arteriovenous malformations, cerebral infarction history, vasculitis. Indications for brachiocephalic CTA are: acute head-neck trauma, ischemia; for outpatient praxis: US suspected vessel stenoses, cerebral infarction history. Selected protocol with post process ing opens up new opportunities for further research of most optimized CTA follow up time, evaluation of recanalization, and randomization of patients, angkalcinguldisekcija, for stenting procedures of dissected arterial segment. authors)

  1. CT diagnosis of lumbosacral conjoined nerve roots

    International Nuclear Information System (INIS)

    Torricelli, P.; Martinelli, C.; Spina, V.

    1987-01-01

    The authors report the observations derived from CT evaluation of 19 cases of lumbosacral conjoined nerve roots; 11 of these have been confirmed by lumbar myelography and/or at surgery. They conclude that CT without intrathecal metrizamide allows the recognition in most cases the presence of conjoined nerve roots and to differentiate them from a herniated disk fragment; this is especially usefull avoid surgical damage of anomalous roots. (orig.)

  2. Recent advances of CT in the diagnosis of abdominal malignancies

    Energy Technology Data Exchange (ETDEWEB)

    Itai, Y [Tokyo Univ. (Japan). Faculty of Medicine

    1980-08-01

    Advantages and limitations of CT in the diagnosis of abdominal malignancies are discussed in liver, pancreas, adrenal gland and recurrent tumor. As to hepatocellular carcinoma, main tumors were clearly demonstrated in 83%, equivocally in 9% and negatively in 8%. Rapid injection of contrast material was useful in dividing hepatic masses into hyper- and hypovascular tumors. Sensitivity of pancreatic cancer was high enough, but CT was of limited value in detecting a resectable one. CT was highly effective in diagnosis of adrenal tumors and recurrent tumors.

  3. CT scan for the diagnosis of maxillary sinus carcinoma

    International Nuclear Information System (INIS)

    Kimura, Yo; Kato, Isao; Aoyagi, Masaru; Kikuchi, Akira; Koike, Yoshio; Suzuki, Hachiro.

    1984-01-01

    A comparative study between the conventional radiological examination and the computed tomographical examination for the diagnosis of maxillary sinus carcinoma was done. CT scan has been more appreciated to detect the tumor invasion in the pterygopalatine fossa, orbit, posterior ethmoid sinus and skull base than the conventional examination. CT scan was most usefull for the determination of size and location of the tumor. The prognosis by the stage-grouping was significantly separated by the new classification with CT scan. Therefore, new TNM classification of maxillary sinus carcinoma with CT scan should be taken into account. (author)

  4. Role of CT scan in diagnosis of acute appendicitis

    International Nuclear Information System (INIS)

    Salem, O.A.; Khasawneh, M.

    2007-01-01

    To evaluate the diagnostic accuracy of the spiral-CT in patients with clinically suspected acute appendicitis. A total of 124 patients referred for CT scan with suspected appendicitis between January 2005 and October 2006 were assessed for the appendiceal size and the presence of signs of appendicitis. The findings were correlated with surgical histopathology. CT scan had a sensitivity of 95 percent and a specifity of 93 percent and an overall accuracy of 92 percent. The use of spiral CT in patients with equivocal clinical presentation suspected of having acute appendicitis can lead to significant improvement in the preoperative diagnosis. (author)

  5. Evaluation of CT findings for diagnosis of pleural effusions

    International Nuclear Information System (INIS)

    Arenas-Jimenez, J.; Alonso-Charterina, S.; Fernandez-Latorre, F.; Gil-Sanchez, S.; Sanchez-Paya, J.; Lloret-Llorens, M.

    2000-01-01

    Computed tomography studies are usually used to assess patients with pleural effusions, and radiologists should be aware of the significance of different CT findings for the diagnosis of the effusion. The purpose of this study was to evaluate CT findings for etiological diagnosis of pleural effusions. Contrast-enhanced CT of the chest of 211 patients with pleural effusion of definite diagnosis were evaluated. The CT images were evaluated for the presence and extent of pleural effusion, thickening or nodules, extrapleural fat and other changes in the mediastinum or lung. The CT scans were read by two independent observers and correlation between them was evaluated. Comparison of CT findings between benign and malignant effusions, between exudates and transudates, and between empyemas and the other parapneumonic effusions were carried out. Kappa values for most CT findings were >0.85. Loculation, pleural thickening, pleural nodules, and extrapleural fat of increased density were only present in exudative effusions. Multiple pleural nodules and nodular pleural thickening were the only pleural findings limited to malignant pleural effusions. The signs were also more frequently seen in empyemas than in other parapneumonic effusions. Computed tomography findings can help to distinguish between transudates and exudates. Although there is some overlap between benign and malignant pleural effusions, pleural nodules and nodular pleural thickening were present almost exclusively in the latter. Although differences between CT findings of empyemas and the other parapneumonic effusions exist, there is no finding which can definitely differentiate between them. (orig.)

  6. Multislice helical CT (MSCT) for mid-facial trauma: optimization of parameters for scanning and reconstruction

    International Nuclear Information System (INIS)

    Dammert, S.; Funke, M.; Obernauer, S.; Grabbe, E.; Merten, H.A.

    2002-01-01

    Purpose: To determine the optimal scan parameters in multislice helical CT (MSCT) of the facial bone complex for both axial scanning and multiplanar reconstructions. Material and Methods: An anthropomorphic skull phantom was examined with a MSCT. Axial scans were performed with continuously increasing collimations (4 x 1.25 - 4 x 2.5 mm), tube current (20 - 200 mA) and table speeds (3.75 mm/rot. and 7.5 mm/rot.). Multiplanar reconstructions in coronal and parasagittal planes with different reconstruction increment and slice thickness were evaluated in terms of image noise, contour artifacts and visualisation of anatomical structures. Results: The best image quality was obtained with a collimation of 4 x 1.25 mm and a - table speed of 3.75 mm/rot. A reconstruction increment of 0.6 mm achieved the best time to image quality relation. With these parameters the bone structures were depicted in an optimal way without artifacts. The tube current could be reduced to 50 mA without significant loss of image quality. The optimized protocol was used for regular routine examinations in patients with facial trauma (n = 66). Conclusions: Low-dose MSCT using thin collimation, low table speed and small reconstruction increments provides excellent data for both axial images and multiplanar reconstructions in patients with facial trauma. An additional examination in coronal orientation is therefore no longer necessary. (orig.) [de

  7. Efficacy of helical CT in evaluating local tumor extent of breast cancer

    International Nuclear Information System (INIS)

    Ozaki, Yutaka

    2001-01-01

    The purpose of this study is to clarify the diagnostic accuracy of helical CT (HCT) in the determination of local tumor extent of breast cancer. One hundred forty consecutive patients with breast cancer, including 87 invasive ductal carcinomas without extensive intraductal components (EIC), 44 invasive ductal carcinomas with EIC, 2 non-invasive ductal carcinomas, and 7 invasive lobular carcinomas, were included in the study. Three-dimensional tumor diameter including whole extent was measured on HCT, and the amount of invasion to fat tissue, skin, pectoral muscle, and chest wall was estimated using a three-step scale. These results were then compared with the pathological findings. Breast cancers appeared as areas of high attenuation compared with the surrounding breast tissue in all patients. Tumor extent was correctly diagnosed by HCT to within a maximum difference of 1 cm in 88 patients (63%) and within 2 cm in 122 patients (87%). Sensitivity, specificity, and accuracy in diagnosing muscular invasion of breast cancer using HCT were 100%, 99%, and 99%, respectively. Sensitivity, specificity, and accuracy in diagnosing skin invasion of breast cancer using HCT were 84%, 93%, and 91%, respectively. HCT was able to visualize all of the tumors and detect the correct tumor extent in most patients. (author)

  8. Efficacy of helical CT in evaluating local tumor extent of breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ozaki, Yutaka [Juntendo Univ., Chiba (Japan). Urayasu Hospital

    2001-04-01

    The purpose of this study is to clarify the diagnostic accuracy of helical CT (HCT) in the determination of local tumor extent of breast cancer. One hundred forty consecutive patients with breast cancer, including 87 invasive ductal carcinomas without extensive intraductal components (EIC), 44 invasive ductal carcinomas with EIC, 2 non-invasive ductal carcinomas, and 7 invasive lobular carcinomas, were included in the study. Three-dimensional tumor diameter including whole extent was measured on HCT, and the amount of invasion to fat tissue, skin, pectoral muscle, and chest wall was estimated using a three-step scale. These results were then compared with the pathological findings. Breast cancers appeared as areas of high attenuation compared with the surrounding breast tissue in all patients. Tumor extent was correctly diagnosed by HCT to within a maximum difference of 1 cm in 88 patients (63%) and within 2 cm in 122 patients (87%). Sensitivity, specificity, and accuracy in diagnosing muscular invasion of breast cancer using HCT were 100%, 99%, and 99%, respectively. Sensitivity, specificity, and accuracy in diagnosing skin invasion of breast cancer using HCT were 84%, 93%, and 91%, respectively. HCT was able to visualize all of the tumors and detect the correct tumor extent in most patients. (author)

  9. CT quantitative diagnosis in fatty liver: a clinical study

    International Nuclear Information System (INIS)

    He Wen; Qian Linxue; Zhao Jixue; Ma Daqing; Feng Jie; Hu Zhihai

    2001-01-01

    Objective: To establish the CT criteria of quantitative diagnosis for liver steatosis by means of studying the CT features of fatty liver cases proven histologically. Methods: Twenty-eight cases of fatty liver were underwent non-enhanced CT scan, and the attenuation of liver parenchyma was measured. To differentiate the degree of fatty liver, the mean CT value and the relative density of hepatic vessels were observed. The quantitative diagnosis was made according to the CT number threshold and the criteria of relative density of hepatic vessels, respectively. Results: Among the 28 cases, there were 17 cases of mild steatosis with mean CT number of 46 HU (32-65 HU), 7 cases of middle degree fatty liver with mean CT number of 28 HU (15-38 HU), and 4 cases of sever fatty liver with mean CT number of 0.2 HU (-7-11 HU). For the relative density of hepatic vessels, 16 of the 17 cases of mild fatty liver had a appearance of hepatic vessels immersion and 1 mild case had reverse hepatic vessels display, 6 of 7 middle degree cases had reverse hepatic vessels display with 1 case having the appearance of hepatic vessels immersion, and all the 4 case of sever steatosis had the appearance of reverse hepatic vessels display with sharp contrast between vessels and the liver parenchyma. The accuracy of quantitative diagnosis was 65.9% and 93.1% by means of criteria of CT number threshold and relative density of hepatic vessels, respectively (x 2 = 7.153, P < 0.01). Conclusion: The criteria of relative density of hepatic vessels is more reliable than that of CT number threshold in quantitative diagnosis of fatty liver

  10. CT diagnosis of invasive hydatidiform mole

    International Nuclear Information System (INIS)

    Lu Mingquan; Jiang Lina; Li Xianxing; Wang Peijun

    2000-01-01

    Objective: To investigate the CT features and the diagnostic value in invasive mole. Methods: Eleven cases (age, 30 to 53 years, mean 40 years) with invasive mole proved by operation and pathology were studied, including 3 cases during peri-menopausal period of eight months, ten months and twelve months respectively. All cases were scanned by CT and enhanced study was done. Results: All cases showed enlargement of uterus of varying degrees. On CT, the density of uterine cavity was similar to that of water, intermingled with spotty patchy and hazy circular isodense shadows. High density stripe-like bleeding foci were found in 3 cases. The outline of uterine cavity was locally disrupted in all case and the muscle layer was thickened in 3 cases. On enhanced CT scan, the lesions in the uterine cavity appeared markedly hyperdense, just like 'the crater' and the 'mole sign'. The muscle layers at the site of disruption showed inhomogeneous enhancement after contrast injection. Conclusion: The CT features of invasive mole are characteristic, with important diagnostic value, especially for those during peri-menopausal period

  11. CT-diagnosis of temporal bone trauma

    Energy Technology Data Exchange (ETDEWEB)

    Valavanis, A.; Stuckmann, G.; Antonucci, F.; Schubiger, O.

    1986-02-01

    73 patients with 78 fractures of the temporal bone were examined by high-resolution computed tomography (CT). Analysis of the CT-findings disclosed 55 longitudinal, 12 transverse, 8 combined and 3 atypical fractures. For determination of the fracture type, axial sections usually proved sufficient. However, for precise topographic analysis of the course of the fracture additional coronal sections were necessary in most of the cases. In the radiologic evaluation of temporal bone fractures detection of associated. Complications is clinically important since these can be surgically corrected. In this series 20 lesions of the ossicular chain were demonstrated by the combined performance of axial and coronal sections and sagittal reformations. High resolution CT demonstrated a lesion of the facial nerve canal in 79% of a patient group with traumatic facial nerve palsy. The most frequent site of injury of the facial nerve canal was the region of the geniculate ganglion. With the use of metrizaminde-CT-cisternography the site of cerebrospinal fluid leakage was demonstrated in 7 of 9 patients with liquorrhea. It is concluded that high-resolution CT is the radiologic method of choice for both topographic evaluation of temporal bone fractures and detection and precise localization of fracture-complications. (orig.).

  12. Effect of CT contrast on volumetric arc therapy planning (RapidArc and helical tomotherapy) for head and neck cancer

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Alan J.; Vora, Nayana [Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA (United States); Suh, Steve [Department of Radiation Physics, City of Hope National Medical Center, Duarte, CA (United States); Liu, An, E-mail: aliu@coh.org [Department of Radiation Physics, City of Hope National Medical Center, Duarte, CA (United States); Schultheiss, Timothy E. [Department of Radiation Physics, City of Hope National Medical Center, Duarte, CA (United States); Wong, Jeffrey Y.C. [Department of Radiation Oncology, City of Hope National Medical Center, Duarte, CA (United States)

    2015-04-01

    The objectives of the study were to evaluate the effect of intravenous contrast in the dosimetry of helical tomotherapy and RapidArc treatment for head and neck cancer and determine if it is acceptable during the computed tomography (CT) simulation to acquire only CT with contrast for treatment planning of head and neck cancer. Overall, 5 patients with head and neck cancer (4 men and 1 woman) treated on helical tomotherapy were analyzed retrospectively. For each patient, 2 consecutive CT scans were performed. The first CT set was scanned before the contrast injection and secondary study set was scanned 45 seconds after contrast. The 2 CTs were autoregistered using the same Digital Imaging and Communications in Medicine coordinates. Tomotherapy and RapidArc plans were generated on 1 CT data set and subsequently copied to the second CT set. Dose calculation was performed, and dose difference was analyzed to evaluate the influence of intravenous contrast media. The dose matrix used for comparison included mean, minimum and maximum doses of planning target volume (PTV), PTV dose coverage, and V{sub 45} {sub Gy}, V{sub 30} {sub Gy}, and V{sub 20} {sub Gy} organ doses. Treatment planning on contrasted images generally showed a lower dose to both organs and target than plans on noncontrasted images. The doses for the points of interest placed in the organs and target rarely changed more than 2% in any patient. In conclusion, treatment planning using a contrasted image had insignificant effect on the dose to the organs and targets. In our opinion, only CT with contrast needs to be acquired during the CT simulation for head and neck cancer. Dose calculations performed on contrasted images can potentially underestimate the delivery dose slightly. However, the errors of planning on a contrasted image should not affect the result in clinically significant way.

  13. CT and sonographic diagnosis of retained surgical sponge

    International Nuclear Information System (INIS)

    Matsumoto, Syunro; Aikawa, Hisayuki; Miyake, Hidetoshi; Mori, Hiromu; Maeda, Tohru; Nishimura, Hiro; Monzen, Yoshio; Ashizawa, Akira; Isomoto, Ichiro.

    1990-01-01

    Seven cases of pathologically proven retained surgical sponge were reviewed and classified into four types, depending on CT and US findings. CT showed a mass with tiny gas bubbles, and sonogram showed an echogenic area with strong posterior shadow (Type I). CT showed an irregular high density mass with no gas bubble, and sonogram showed an echogenic area with strong posterior shadow (Type II). CT showed a low density mass with irregular internal high density areas, and somogram showed a cystic mass with zigzag internal components (Type III). CT showed an eliptic high density mass with low density area internally. Judging from the experiment and operative findings, these patterns were decided by the number and status of the gauze, volume of the exudate and hematoma, and status of the granulation. The author concludes that these characteristic CT and US findings, together with a history of surgery, permit the correct diagnosis of retained surgical sponge. (author)

  14. CT and MRI diagnosis of renal oncocytoma

    International Nuclear Information System (INIS)

    Ren Shoujun; Wang Wenjia; Pan Shaohui; Gao Ji; Du Pengfei; Lu Fengxi; Wang Xiaohong

    2007-01-01

    Objective: To discuss the CT and MRI diagnostic value of renal oncocytoma and to improve the recognition of renal oncocytoma. Methods: Two cases of renal oncocytoma confirmed by pathology were retrospectively analyzed and related papers were reviewed. Results: Two cases were located in renal cortex, with smooth and sharp border, extruding outside of the kidneys. CT showed solid masses with lower density in center area as 'star'. On MRI T 1 WI and T 2 WI they also showed solid masses with low T 1 and high T 2 signal inensity in center area as 'star'. After contrast enhancement, the masses represented moderate enhancement and the central part did not show enhancement. Conclusion: Renal oncocytoma is a kind of rare nephroma provided with some characteristics in CT and MRI. (authors)

  15. Diagnosis of chondromalacia patellae using CT arthrography

    Energy Technology Data Exchange (ETDEWEB)

    Reiser, M.; Karpf, P.M.; Bernett, P.

    1982-08-01

    Using anatomical specimens for experimental investigations, the physical-technical prerequisites for proper demonstration of the femoro-patellar articulation were determined and the following results obtained: hyaline cartilage possesses an attenuation value of 25-35 HU; artificial lesions from 1 mm. deep and 2 mm. wide minimum can be visualized; the use of positive contrast medium is best suited for demonstration of chondral lesions. In clinical practice we found that the various stages of cartilaginous degeneration peculiar to chondromalacia (Fruend I to III) are clearly demonstrated by CT arthrography. In CT the predisposing changes in the morphology of the patella and the femoro-patellar articulation are more precisely defined than in conventional tangential roentgenograms. In 69 cases the CT arthrographic findings could be verified at operation. However, the extent and severity of the lesions was, at times, underestimated.

  16. Demonstration of the right inferior phrenic artery by using multislice helical CT

    International Nuclear Information System (INIS)

    Zhao Shaohong; Liu Xin; Cai Zulong; Zhao Hong; Yang Li

    2006-01-01

    Objective: To demonstrate the origin of the right inferior phrenic artery (RIPA) in normal and hepatocellular carcinoma (HCC) patients and provide valuable anatomical information for angiographers before and after transcatheter arterial chemoembolization (TACE). Methods: Four hundred and forty consecutive patients including 133 HCC cases who had biphase abdominal CT were assessed in this study. The routine abdominal enhanced CT scan (GE, LightSpeed16) was performed with 120 kV, 200-240 mAs, 10 mm collimation, 1.375 pitch, and 10 mm reconstruction interval at 22-25 seconds for arterial phase triggered by timing bolus, 60 seconds for portal venous phase after injection of 100 ml contrast material (300 mg I/ml) at a rate of 3.5 ml/s. Multiplanar reconstruction (MPR) and maximum intensity projection (MIP) images were generated using 1.25 mm images reconstructed with 1 mm interval in arterial phase and reviewed by two radiologists. An enhanced artery medial-posterior to the IVC, originated from aorta or its branches to the diaphragmatic dome was interpreted as the RIPA. Results: The RIPA was showed in all 440 patients (100%). Among 218 (49.5%) RIPAs originated from the aorta, 140 were from the fight side of the aorta, 22 from the left side of the aorta, 56 from the anterior wall of the aorta, 36 RIPAs had the same origin with the left inferior phrenic artery. Among 138 (31.4%) RIPAs from the celiac artery, 10 RIPAs had the same origin with the left gastric artery, and 33 RIPAs had the same origin with the left inferior phrenic artery. 78 (17.7%) were from the fight renal artery, 6 (1.4%) were from the left gastric artery (the left gastric artery from aorta). The dilatation of the RIPA was demonstrated in 16 of 133 hepatocellular carcinoma patients. Conclusion: Multislice helical CT could demonstrate the origin of the RIPA in arterial phase and provide useful anatomical information for angiographer before and after TACE. (authors)

  17. CT diagnosis of acute aortic dissection

    International Nuclear Information System (INIS)

    Ogawa, Noriko; Kobayashi, Takeshi

    1989-01-01

    Sixteen (47.5%) of 35 patients with acute aortic dissection showed a non-opacified crescent in the aorta on an initial contrast CT. Seven of these 16 patients underwent cineangiography soon after the initial CT, and in all 7 patients, neither an intimal tear nor an intimal flap was obtained. All but one of above 16 patients were followed by CT. Mean duration of follow-up was 9.6 months. In 10 of 15 patients with non-opacified false lumen, the false lumen remained non-opacified until the last examination. Moreover, in 6 of these 10 patients, the false lumen shrunk, and in the other 3, it disappeared completely on follow-up CT. On the other hand, in remaining 5 of these 15 patients who were initially diagnosed to have non-opacified false lumen, the false lumen became opacified and enlarged in size on follow-up CT performed in the first 14 weeks. Moreover, in 4 of these 5 patients, the false lumen became opacified in the only first 6 weeks. No matter how intensive care should be paid at least for the first 6 weeks, it seems that patients with aortic dissection which have non-opacified false lumen had good prognosis in comparison to patients with ordinary aortic dissections which have opacified false lumen. We believe aortic dissection with non-opacified false lumen may consist of two type of aortic dissection, one has no intimal tear, the other has some intimal tears and a thrombosed false lumen. In conclusion, CT is the most useful modality in diagnosing acute aortic dissection. The reasons are the incidence of acute aortic dissection with non-opacified false lumen was high, patients with non-opacified false lumen had good prognosis, and it was difficult to diagnose aortic dissection with non-opacified false lumen by conventional cineangiography and/or DSA. (author)

  18. CT diagnosis with shoulder joint injuries

    International Nuclear Information System (INIS)

    Gay, B.; Hoerl, M.; Schindler, G.

    1986-01-01

    With recidivistic shoulder luxation the CT examination makes possible the objective comprehension of predisposable anatomical evidence as well as the proof of posttraumatic changes. Changes in the acetabular margin (Bankart lesion) as well as in the humerus head (Hills-Sachs lesion) are depicted with recidivistic shoulder luxation as the morphological substrate of the posttraumatic damage. Individual examinations of 83 patients with recidivistic shoulder luxations showed that the mentioned changes often appear in combinations. With the CT examination the Hills-Sachs lesion can be comprehended and its location, extension and depth can be judged as well. (orig./MG) [de

  19. Diagnosis of pancreatic tumors by spiral angio CT

    International Nuclear Information System (INIS)

    Miura, Kohi; Nakao, Norio; Takayasu, Yukio; Okawa, Tomohisa

    1995-01-01

    Spiral angio were performed with injection of 30 ml of contrast material at a rate of 1 ml/sec with a scan delay of 6 sec through catheter into the celiac artery while the blood flow of the superior mesenteric artery (SMA) was occluded by the inflated balloon catheter. Spiral CT scans were obtained using Somatom Plus (Siemens). Parameter for spiral CT were 24-sec acquisition time, 5 mm collimation, 5 mm/sec table incrementation. Reconstructions were performed every 5 mm. Pancreatic cancers were characteristically depicted with spiral angio CT as hypodensity relative to normal enhanced pancreatic parenchyma. On dynamic angio CT studies performed in pancreatic cancers, the area of cancer and normal parenchyma had maximum level of enhancement at 10-15 sec after injection of contrast material via catheter into the celiac, and there was no difference in enhancement between tumor and normal parenchyma. On the other hand, the lesions of cancer were revealed as hypodensity with spiral angio CT. In case of chronic pancreatitis, the enhancement of the entire pancreas obtained with spiral angio CT was homogeneous. Insulinoma in the tail of pancreas was detected by spiral angio CT but was not detected by both selective angiography and conventional CT. Three-dimensional (3-D) rendering spiral angio CT data shows the extent of vascular involvement by pancreatic cancer and provides useful information for surgical planning. Spiral angio CT is the most useful procedure for diagnosis of pancreatic tumor. (author)

  20. MRI versus CT in the diagnosis of Nelson's syndrome

    International Nuclear Information System (INIS)

    Kasperlik-Zaluska, A.; Walecki, J.; Brzezinski, J.; Jeske, W.; Migdalska, B.; Bonicki, W.; Brzezinska, A.; Makowska, A.

    1997-01-01

    The purpose of the study was to evaluate the utility of MRI and CT in the diagnosis of Nelson's syndrome, i. e. pituitary tumours in patients bilaterally adrenalectomized for Cushing's disease. Thirteen patients, followed up for 5-29 years after adrenalectomy, were studied. In 6 of them CT and MRI revealed no changes in the pituitary gland. In the remaining 7 patients only three CT scans were suggestive of a pituitary adenoma. MRI studies with administration of gadodiamide confirmed the CT diagnosis of Nelson's tumour in 3 patients and disclosed microadenomas in a further 4 patients. Neurosurgical treatment in 4 patients confirmed the MRI findings. Additionally CT and MRI examinations were performed in 5 patients suspected of a recurrent Nelson's tumour 3-11 years after neurosurgery. MRI visualized recurrent adenomas in 3 patients that were not well seen by CT scans. In our experience MRI was more effective than CT in the diagnosis of Nelson's syndrome. (orig.). With 3 figs., 1 tab

  1. Diagnosis of gynecologic pelvic masses by CT scans

    International Nuclear Information System (INIS)

    Ito, Hisao; Kubo, Atsushi; Takagi, Yaeko; Kinoshita, Fumio; Maekawa, Akira.

    1981-01-01

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

  2. Cost-effectiveness analysis on the results of screening of lung cancer using helical CT conducted by the anti-lung cancer association (ALCA)

    International Nuclear Information System (INIS)

    Iinuma, Takeshi; Kaneko, Masahiro; Moriyama, Noriyuki; Misawa, Jun

    1999-01-01

    To compare Yen/person saved in lung cancer screening using helical CT with Yen/person in the screening using conventional direct chest X-rays conducted under the Anti-lung cancer association program of the Tokyo Health Service Association. A mathematical model for cancer screening was used to estimate net number of person relieved from lung cancer by the screening and net cost required for the screening. Finally cost-effectiveness ratios in terms of Yen/person saved were calculated and compared between the two programs. Several important variables employed in the model were as follows: 5 year survival rate in chest X-ray group was 50%, and the rate in helical CT group was 75%. Cost of screening in the chest X-ray group was 15,000 Yen, and that in the helical CT group was 25,000 Yen. Cost/person screened was 14,470 Yen for chest X-ray and 21,890 Yen for helical CT. Cost/person saved was 267 x 10 5 Yen in X-ray group and 112 x 10 5 Yen in CT group. Thus the cost was higher, but cost-effectiveness ratio was better in the CT screening group. Helical CT can be adopted for lung cancer screening in stead of chest X-ray if total cost is affordable. (author)

  3. Pitfalls in CT diagnosis of appendicitis: pictorial essay

    International Nuclear Information System (INIS)

    Shademan, Ashkan; Tappouni, Rafel F.R.

    2013-01-01

    Despite the high diagnostic accuracy of CT for appendicitis, numerous pitfalls exist that may result in a misdiagnosis. This pictorial review outlines the potential pitfalls in the CT diagnosis of appendicitis that includes atypical position of the appendix and coexisting pathologies. Various mimickers of appendicitis and clinical dilemmas will be highlighted. Upon completion, the reviewer should have an improved ability to recognise appendicitis mimickers and identify equivocal or atypical findings.

  4. FDG-PET, CT, MRI for diagnosis of local residual or recurrent nasopharyngeal carcinoma, which one is the best? A systematic review

    International Nuclear Information System (INIS)

    Liu Tao; Xu Wen; Yan Weili; Ye Ming; Bai Yongrui; Huang Gang

    2007-01-01

    Purpose: To perform a systematic review to compare FDG-PET, CT, and MRI imaging for diagnosis of local residual or recurrent nasopharyngeal carcinoma. Materials and methods: MEDLINE, EMBASE, the CBMdisc databases and some other databases were searched for relevant original articles published from January 1990 to June 2007. Inclusion criteria were as follows: Articles were reported in English or Chinese; FDG-PET, CT, or MRI was used to detect local residual or recurrent nasopharyngeal carcinoma; histopathologic analysis and/or close clinical and imaging follow-up for at least 6 months were the reference standard. Two reviewers independently extracted data. A software called 'Meta-DiSc' was used to obtain pooled estimates of sensitivity, specificity, diagnostic odds ratio (DOR), summary receiver operating characteristic (SROC) curves, and the Q* index. Results: Twenty-one articles fulfilled all inclusion criteria. The pooled sensitivity estimates for PET (95%) were significantly higher than CT (76%) (P 0.05). Conclusion: FDG-PET was the best modality for diagnosis of local residual or recurrent nasopharyngeal carcinoma. The type of analysis for PET imaging and the section thickness for CT would affect the diagnostic results. Dual-section helical and multi-section helical CT were better than nonhelical and single-section helical CT

  5. Clinical evaluation of high-resolution CT, 1. CT diagnosis of liver tumors and its limit

    Energy Technology Data Exchange (ETDEWEB)

    Araki, T [Tokyo Univ. (Japan). Faculty of Medicine

    1980-03-01

    To estimate diagnostic accuracy of CT in liver tumors, CT diagnosis in 120 patients with primary hepatocellular carcinoma was discussed. As a result, primary hepatocellular carcinoma less than 2 cm in diameter could not be visualized by CT. Even tumors between 4 and 8 cm in diameter showed false negative caused by isodense tumors on images of 4 patients. To improve the detectability of liver tumors by CT, the higher resolution of low contrast regions on images are required. As a method to improve qualitative diagnosis of liver tumors, rapid intravenous injection of contrast medium was performed on 42 patients with liver tumors, As a result, images reflecting vascularity of tumors were obtained, and the differential diagnosis was possible to some extent by observing the movement of the contrast. Especially, cavernous hemangioma could be distinguished from hepatocellular carcinoma, because cavernous hemangioma showed specific images and could be diagnosed accurately.

  6. US and CT findings in the diagnosis of tuberculous peritonitis

    Energy Technology Data Exchange (ETDEWEB)

    Demirkazik, F.B. [Dept. of Radiology, School of Medicine, Hacettepe Univ., Ankara (Turkey); Akhan, O. [Dept. of Radiology, School of Medicine, Hacettepe Univ., Ankara (Turkey); Oezmen, M.N. [Dept. of Radiology, School of Medicine, Hacettepe Univ., Ankara (Turkey); Akata, D. [Dept. of Radiology, School of Medicine, Hacettepe Univ., Ankara (Turkey)

    1996-07-01

    Purpose: To evaluate the ultrasonographic and CT findings of tuberculous peritonitis. Material and Methods: Ultrasonographic and CT findings of 11 patients with the ascitic type of tuberculous peritonitis were reviewed. Results: All patients had ascites, and ultrasonography (US) demonstrated fine complete and incomplete mobile septations in 10 patients. In 5 of them, the ascites had a lattice-like appearance. Diffuse regular peritoneal thickening was detected in all patients by CT and in 10 patients by US. CT demonstrated infiltration of the greater omentum in 9 patients, whereas US showed omental thickening in only 5 patients. Conclusion: Peritoneal and omental thickening detected by CT and ascites with fine, mobile septations shown by US strongly suggest the ascitic type of tuberculous peritonitis. The 2 imaging modalities should be used together for accurate diagnosis of tuberculous peritonitis. (orig.).

  7. US and CT findings in the diagnosis of tuberculous peritonitis

    International Nuclear Information System (INIS)

    Demirkazik, F.B.; Akhan, O.; Oezmen, M.N.; Akata, D.

    1996-01-01

    Purpose: To evaluate the ultrasonographic and CT findings of tuberculous peritonitis. Material and Methods: Ultrasonographic and CT findings of 11 patients with the ascitic type of tuberculous peritonitis were reviewed. Results: All patients had ascites, and ultrasonography (US) demonstrated fine complete and incomplete mobile septations in 10 patients. In 5 of them, the ascites had a lattice-like appearance. Diffuse regular peritoneal thickening was detected in all patients by CT and in 10 patients by US. CT demonstrated infiltration of the greater omentum in 9 patients, whereas US showed omental thickening in only 5 patients. Conclusion: Peritoneal and omental thickening detected by CT and ascites with fine, mobile septations shown by US strongly suggest the ascitic type of tuberculous peritonitis. The 2 imaging modalities should be used together for accurate diagnosis of tuberculous peritonitis. (orig.)

  8. CT diagnosis and pathological basis of localized malignant peritoneal mesothelioma

    International Nuclear Information System (INIS)

    Zheng Xiangwu; Wu Enfu; Yin Weiwei; Zhou Weizhong; Zhu Qijian; Zheng Xiaofeng

    2001-01-01

    Objective: To study the value of CT diagnosis in localized malignant peritoneal mesothelioma. Methods: CT features of 4 cases with localized malignant peritoneal mesothelioma and the pathological basis were analyzed. Results: All 4 cases showed a large localized mass with an average size of 13 cm. 3 of 4 cases were cystic-solid predominantly multi-cystic; another case was solid accompanied by necrosis. Contrast CT demonstrated marked enhancement in the solid portion of tumor in all 4 cases, the highest CT density was 106 HU(average 76 HU). There was no distant metastasis and ascites. Conclusion: Multi-cysts, remarkable enhancement of the solid area and no distant metastasis may be the main characteristic CT features of localized malignant peritoneal mesothelioma

  9. CT Angiography in the Diagnosis of Brain Death

    International Nuclear Information System (INIS)

    Sawicki, Marcin; Bohatyrewicz, Romuald; Walecka, Anna; Sołek-Pastuszka, Joanna; Rowiński, Olgierd; Walecki, Jerzy

    2014-01-01

    Summary Brain death is defined as the irreversible cessation of functioning of the entire brain, including the brainstem. Brain death is principally established using clinical criteria including coma, absence of brainstem reflexes and loss of central drive to breathe assessed with apnea test. In situations in which clinical testing cannot be performed or when uncertainty exists about the reliability of its parts due to confounding conditions ancillary tests (i.a. imaging studies) may be useful. The objective of ancillary tests in the diagnosis of brain death is to demonstrate the absence of cerebral electrical activity (EEG and evoked potentials) or cerebral circulatory arrest. In clinical practice catheter cerebral angiography, perfusion scintigraphy, transcranial Doppler sonography, CT angiography and MR angiography are used. Other methods, like perfusion CT, xenon CT, MR spectroscopy, diffusion weighted MRI and functional MRI are being studied as potentially useful in the diagnosis of brain death. CT angiography has recently attracted attention as a promising alternative to catheter angiography – a reference test in the diagnosis of brain death. Since 1998 several major studies were published and national guidelines were introduced in several countries (e.g. in France, Austria, Switzerland, the Netherlands and Canada). This paper reviews technique, characteristic findings and criteria for the diagnosis of cerebral circulatory arrest in CT angiography

  10. Optimized enhancement in helical CT: Experiences with a real-time bolus tracking system in 628 patients

    International Nuclear Information System (INIS)

    Kirchner, J.; Kickuth, R.; Laufer, U.; Noack, M.; Liermann, D.

    2000-01-01

    AIMS: Ultrafast detector technology enables bolus-triggered application of contrast media. In a prospective study we investigated the benefit of this new method with the intention of optimizing enhancement during examination of the chest and abdomen. MATERIALS AND METHODS: In total, we examined 548 patients under standardized conditions. All examinations were performed on a Somatom Plus 4 Power CT system (Siemens Corp., Forchheim, Germany) using the CARE-Bolus software. This produces repetitive low-dose test images (e.g. for the lung: 140 kV, 43 mA, TI 0.5 s) and measures the Hounsfield attenuation in a pre-selected region of interest. After exceeding a defined threshold, a diagnostic spiral CT examination was begun automatically. The data obtained from 321 abdominal CT and 179 lung CT examinations were correlated with different parameters such as age, weight and height of the patients and parameters of vascular access. In a group of 80 patients, the injection of contrast medium was stopped after reaching a pre-defined threshold of an increase of 100 HU over the baseline. Then, we assessed the maximal enhancement of liver, pulmonal artery trunk and aortic arch. RESULTS: There was no correlation between bolus geometry and age, body surface or weight. In helical CT of the abdomen the threshold was reached after a mean trigger time of 27 s (range 13-67 s) and only 65 ml (range 41-105 ml) of contrast medium were administered. In helical CT of the lung the threshold was reached after 21 s (range 12-48 s) and the mean amount of administered contrast medium was 48 ml (range 38-71 ml). CONCLUSION: Bolus triggering allows optimized enhancement of the organs and reduces the dose of contrast material required compared with standard administration. Kirchner, J. (2000). Clinical Radiology 55, 368-373

  11. Optimized enhancement in helical CT: experiences with a real-time bolus tracking system in 628 patients.

    Science.gov (United States)

    Kirchner, J; Kickuth, R; Laufer, U; Noack, M; Liermann, D

    2000-05-01

    Ultrafast detector technology enables bolus-triggered application of contrast media. In a prospective study we investigated the benefit of this new method with the intention of optimizing enhancement during examination of the chest and abdomen. In total, we examined 548 patients under standardized conditions. All examinations were performed on a Somatom Plus 4 Power CT system (Siemens Corp., Forchheim, Germany) using the CARE-Bolus software. This produces repetitive low-dose test images (e.g. for the lung: 140 kV, 43 mA, TI 0.5 s) and measures the Hounsfield attenuation in a pre-selected region of interest. After exceeding a defined threshold, a diagnostic spiral CT examination was begun automatically. The data obtained from 321 abdominal CT and 179 lung CT examinations were correlated with different parameters such as age, weight and height of the patients and parameters of vascular access. In a group of 80 patients, the injection of contrast medium was stopped after reaching a pre-defined threshold of an increase of 100 HU over the baseline. Then, we assessed the maximal enhancement of liver, pulmonal artery trunk and aortic arch. There was no correlation between bolus geometry and age, body surface or weight. In helical CT of the abdomen the threshold was reached after a mean trigger time of 27 s (range 13-67 s) and only 65 ml (range 41-105 ml) of contrast medium were administered. In helical CT of the lung the threshold was reached after 21 s (range 12-48 s) and the mean amount of administered contrast medium was 48 ml (range 38-71 ml). Bolus triggering allows optimized enhancement of the organs and reduces the dose of contrast material required compared with standard administration. Copyright 2000 The Royal College of Radiologists.

  12. Evaluation of residual hepatocellular carcinoma after transcatheter arterial chemoembolization: Comparison between contrast-enhanced helical CT and contrast-enhanced power doppler ultrasonography

    International Nuclear Information System (INIS)

    Kim, Seung Hoon; Lim, Hyo Keun; Lee, Won Jae

    2001-01-01

    To evaluate the effectiveness of contrast-enhanced helical CT and contrast-enhanced power doppler ultrasonography (PDUS) in assessing the therapeutic effect of transcatheter arterial chemoembolization (TACE) in hepatocellular carcinomas (HCCs). The follow-up contrast-enhanced helical CT and contrast-enhanced PDUS were performed for twenty-nine nodular HCCs from twelve patients previously treated with TACE. We defined the residual HCCs as intratumoral enhancing area on contrast-enhanced helical CT and color signal on contrast-enhanced PDUS. The interval between two examinations was less than 2 weeks (mean, 9 days). Two radiologists evaluated two examinations by consensus, and the results of these two examination were compared with the findings of other examinations including CT, angiography, and/or pathology to calculate the sensitivity, specificity and accuracy of two examinations. Of the 29 HCCs, 20 had residual HCCs whereas no residual HCCs in 9 HCCs on pathologic examination and/or follow-up radiologic study. The sensitivity, sensitivity and accuracy of contrast-enhanced helical CT were 65 (13/20), 89 (8/9), and 72% (21/29) while those of contrast-enhanced PDUS were 100 (20/20), 89 (8/9) and 97% (28/29), respectively. A microbubble contrast-enhanced PDUS was more effective in the detection of residual tumor in HCCs following TACE than contrast-enhanced helical CT.

  13. Experimental study of quantity to be taken as patient dose in helical multi-slice CT scan

    International Nuclear Information System (INIS)

    Liu Lantao; Wei Kedao; Yue Brorong; Wang Jianchao

    2009-01-01

    Objective: To bring forward a novel quantity which is used to be taken as effective dose in helical multi - slice CT scan and to validate it by experiment. Methods: Dot chamber and pencil-chamber were used to measure the doses which were performed under axial mode and helical multi-slice mode. Then the readings of doses were compared and analyzed. Results: The dose reading from dot chamber was close to the one from pencil - chamber under axial mode. The ratio is 1.14 for the readings from dot chamber under two scan modes and is 2.88 for the readings from pencil-chamber under two scan modes. Conclusions: The dose measured from dot chamber is an effective quantity to be taken as effective dose. However it is insufficient that the CTDI and DLP be used to be taken as effective dose as the limitation of pencil-chamber in length. (authors)

  14. Computed tomography (CT) and diastematomyelia's diagnosis

    International Nuclear Information System (INIS)

    Santos, M.B. dos; Luca, V. de; Ferreira, M.A.S.; Barros, A.P. de

    1982-01-01

    After a case of diastematomyelia observed at the University Hospital (Federal University of Rio de Janeiro, Brazil) a review is done of the pertaining literature, and the contribution of the computed tomography for the diagnosis of this disease is emphasized. (Author) [pt

  15. Perforated appendicitis: accuracy of CT diagnosis and correlation of CT findings with the length of hospital

    International Nuclear Information System (INIS)

    Siddiqui, H.A.; Afzal, S.

    2007-01-01

    To determine the sensitivity and specificity of CT findings in the differentiation of perforated from nonperforated appendicitis and correlate CT diagnosis with the length of hospital stay. The study included 70 patients who presented with right lower quadrant abdominal pain and underwent preoperative CT scan followed by appendectomy. Patients were divided into two groups of having perforated and nonperforated appendicitis on the basis of CT scan findings. The surgical and pathological reports combined were considered the reference standard for the diagnosis of perforated appendicitis. Various CT scan findings and average duration of hospital stay in days was compared by t-test. Twenty-six (37%) of 70 patients had perforated appendicitis. It was correctly identified on pre-operative CT scan in 18 patients. There were 18 true positive diagnoses, 43 true negative diagnoses, 1 false positive diagnosis and 8 false negative diagnoses which yielded a sensitivity of 69%, specificity of 97%, positive predictive value of 94% and negative predictive value of 84%. Mean length of hospital stay in perforated group was 6.3 days and 2.9 days in nonperforated group. Severe periappendiceal inflammation, periappendiceal and or abdominopelvic fluid and abscess were significantly associated with perforated appendicitis and with a significant longer hospital stay (p <.001). CT scan is 69% sensitive and 97% specific for the diagnosis of perforated appendicitis and constellation of CT findings can be used to select patients with perforated appendicitis for initial non-operative management. Presence of CT signs of significant appendiceal inflammation is independent predictor of longer hospital stay. (author)

  16. Optimization of multi-slice helical respiration-correlated CT: the effects of table speed and rotation time

    International Nuclear Information System (INIS)

    Wink, Nicole M; McNitt-Gray, Michael F; Solberg, Timothy D

    2005-01-01

    While respiration-correlated CT is gaining acceptance in clinical radiotherapy, the effect of scanning parameters on the image quality has yet to be addressed. The intent of this study was to characterize the effects of gantry rotation and table speed on various image quality characteristics in multi-slice, helical, retrospectively-gated CT images. Images of stationary and moving phantoms were obtained in helical mode on a 20-slice CT scanner. Motion was generated by a computer-controlled platform capable of moving simultaneously in two dimensions. Motion was monitored using a pressure gauge inserted inside an adjustable belt. Selected scans were retrospectively gated into ten phases based on the monitored motion. Gantry rotation speeds of 0.5 s and 1.0 s were evaluated with pitches ranging from 0.1 to 0.45. Several parameters, including calculated object volumes, trajectory (movement from peak to trough), deformation (actual volume divided by volume created with the maximum diameter of contoured object) and z-axis resolution, were used to characterize image quality. These studies indicate that for objects in the peak phase of a movement pattern that simulates breathing, retrospectively gated scans using fast gantry rotation speeds produce volume, trajectory, deformation and z-axis resolution results comparable with those of a stationary object

  17. Aortic non communicating dissections. A study with helical CT; Studio dell'ematoma intramurale aortico. Aspetti con Tomografia Computerizzata spirale

    Energy Technology Data Exchange (ETDEWEB)

    Midiri, M.; Strada, A.; Stabile Ianora, A.A.; Rotondo, A.; Angelelli, G. [Bari Univ., Bari (Italy). Dipt. di Medicina Interna e Medicina Pubblica, Sez. di Diagnostica per Immagini; Scialpi, M. [Ospedale SS. Annunziata, Taranto (Italy); D' Agostino, D.; De Luca Tupputi Schinosa, L. [Bari Univ., Bari (Italy). Dipt. Emergenze Trapianto d' Organo, Sez. di Cardiochirurgia

    2000-09-01

    The evaluate the signs of aortic intramural hematoma with helical CT and the diagnostic role of this technique in patients with this condition. It was reviewed the CT findings of 396 patients submitted to emergency examinations for suspected aortic dissection from 1995 to 1999. Only 18 patients (6 women and 12 men) had CT signs of aortic intramural hematoma. Helical CT studies were carried out with the following parameters: slice thickness 10 mm, reconstruction index 10, feed 1.5 mm, conventional algorithm with minimum values of 130 kV and 125mA. All patients were examined with dynamic contrast-enhanced CT, before and after a power injection of 130 mL ionic contrast material. It was studied: hematoma localization and longitudinal extension; thickness and density of aortic wall; presence and location of intimal calcifications; integrity of intimal wall; hemo mediastinum and/or hemo thorax. Aortic wall thickening appeared as a high density crescent-shaped area at baseline CT and had low density on enhanced images in all patients. Thickening was eccentric in 14/18 patients and concentric in 4/18 only; it always exceeded 4 mm. It was found some intimal calcifications in 8 patients and hemo thorax and/or hemo mediastinum in 9 patients. A patient with type A hematoma died of cardiac tamponade a few hours after CT diagnosis. Six patients (5 type B and 1 type A) underwent anti-hypertensive treatment and radiological follow-up. Eleven patients (6 type A and 5 type B) underwent prosthesis replacement and 5 of them (3 type A and 2 type B) died of postoperative complications. In the 5 type B patients surgery was performed because of treatment-resistant pain and of the onset of ischemic complications to abdominal organs caused by involvement of the main collateral branches of the aorta. One patient with type A hematoma was submitted to drug treatment because it was judged unresectable. Intramural hematoma of the aorta is a distinct pathological entity, which should not be

  18. Association of achondroplasia with Down syndrome: difficulty in prenatal diagnosis by sonographic and 3-D helical computed tomographic analyses.

    Science.gov (United States)

    Kaga, Akimune; Murotsuki, Jun; Kamimura, Miki; Kimura, Masato; Saito-Hakoda, Akiko; Kanno, Junko; Hoshi, Kazuhiko; Kure, Shigeo; Fujiwara, Ikuma

    2015-05-01

    Achondroplasia and Down syndrome are relatively common conditions individually. But co-occurrence of both conditions in the same patient is rare and there have been no reports of fetal analysis of this condition by prenatal sonographic and three-dimensional (3-D) helical computed tomography (CT). Prenatal sonographic findings seen in persons with Down syndrome, such as a thickened nuchal fold, cardiac defects, and echogenic bowel were not found in the patient. A prenatal 3-D helical CT revealed a large head with frontal bossing, metaphyseal flaring of the long bones, and small iliac wings, which suggested achondroplasia. In a case with combination of achondroplasia and Down syndrome, it may be difficult to diagnose the co-occurrence prenatally without typical markers of Down syndrome. © 2014 Japanese Teratology Society.

  19. CT in diagnosis of thoracolumbar region diseases

    International Nuclear Information System (INIS)

    Dimitrov, I.; Karadjova, M.

    2003-01-01

    The lumbalgia caused by affected thoracolumbar transition (Th 11 -L 2 ) imitates the clinical symptomatic of disc lesions in the lower lumbar segments. The syndrome is presented by a pain projected in the area of the three branchings of the spinal nerves, coming from thoracolumbar segments. The aim of this study is to determine the pathological processes, causing the clinical symptoms of this syndrome, using computer tomography. 51 patients are studied with clinically proved thoracolumbar transition syndrome: 14 men and 37 women. CT slices of 96 vertebral segments are made. Two patient are scanned at Th 11 -Th 12 and L 1 -L 2 . Only Th 12 -L 1 scans are made on 10 patients and 42 are made on two neighbouring segments (41 of them on Th 11 -Th 12 and Th 12 -L 1 and one on Th 11 -L 1 and L 1 -L 2 ). An asymmetry (facet tropism) has been found at 59 levels, 21 if them are with spondiloarthrosis. Spondiloarthrosis has been found in 24 segments - 21 of them with osteochondrosis, one with disc prolapse, and 2 with disc protrusion. It is also found osteoporotic changes osteolysis in multiple myeloma, metastasis etc. During the 3 level examination no evidence for either of the mentioned changes is obtained. The CT slices of two neighbouring segments showed an unexpected change from thoracic to lumbar type of the intervertebral joints in 34 patients. The results from this study support the hypothesis about joints origin of the clinical symptoms of the thoracolumbar transition and demonstrate the importance of the computer tomography as a diagnostic method in this disease

  20. The quality of reconstructed 3D images in multidetector-row helical CT: experimental study involving scan parameters

    International Nuclear Information System (INIS)

    Shin, Ji Hoon; Lee, Ho Kyu; Choi, Choong Gon; Suh, Dae Chul; Lim, Tae Hwan; Kang, Weechang

    2002-01-01

    To determine which multidetector-row helical CT scanning technique provides the best-quality reconstructed 3D images, and to assess differences in image quality according to the levels of the scanning parameters used. Four objects with different surfaces and contours were scanned using multidetector-row helical CT at three detector-row collimations (1.25, 2.50, 5.00 mm), two pitches (3.0, 6.0), and three different degrees of overlap between the reconstructed slices (0%, 25%, 50%). Reconstructed 3D images of the resulting 72 sets of data were produced using volumetric rendering. The 72 images were graded on a scale from 1 (worst) to 5 (best) for each of four rating criteria, giving a mean score for each criterion and an overall mean score. Statistical analysis was used to assess differences in image quality according to scanning parameter levels. The mean score for each rating criterion, and the overall mean score, varied significantly according to the scanning parameter levels used. With regard to detector-row collimation and pitch, all levels of scanning parameters gave rise to significant differences, while in the degree of overlap of reconstructed slices, there were significant differences between overlap of 0% and of 50% in all levels of scanning parameters, and between overlap of 25% and of 50% in overall accuracy and overall mean score. Among the 18 scanning sequences, the highest score (4.94) was achieved with 1.25 mm detector-row collimation, 3.0 pitch, and 50% overlap between reconstructed slices. Comparison of the quality of reconstructed 3D images obtained using multidetector-row helical CT and various scanning techniques indicated that the 1.25 mm, 3.0, 50% scanning sequence was best. Quality improved as detector-row collimation decreased; as pitch was reduced from 6.0 to 3.0; and as overlap between reconstructed slices increased

  1. Diagnosis demystified: CT as diagnostic tool in endodontics

    Science.gov (United States)

    Shruthi, Nagaraja; Sreenivasa Murthy, B V; Sundaresh, K J; Mallikarjuna, Rachappa

    2013-01-01

    Diagnosis in endodontics is usually based on clinical and radiographical presentations, which are only empirical methods. The role of healing profession is to apply knowledge and skills towards maintaining and restoring the patient's health. Recent advances in imaging technologies have added to correct interpretation and diagnosis. CT is proving to be an effective tool in solving endodontic mysteries through its three-dimensional visualisation. CT imaging offers many diagnostic advantages to produce reconstructed images in selected projection and low-contrast resolution far superior to that of all other X-ray imaging modalities. This case report is an endeavour towards effective treatment planning of cases with root fracture, root resorption using spiral CT as an adjuvant diagnostic tool. PMID:23814212

  2. Unusual presentation of a pancreatic insulinoma in helical CT and dynamic contrast-enhanced MR imaging: case report

    Energy Technology Data Exchange (ETDEWEB)

    Iglesias, A.; Arias, M.; Brasa, J. [Unidad de Resonancia Magnetica (Medtec), Hospital Xeral-Cies, Vigo (Spain); Casal, M. [Unidad de Radiologia Intervencionista, Hospital Xeral-Cies, Vigo (Spain); Paramo, C. [Servicio de Endocrinologia, Hospital Xeral-Cies, Vigo (Spain); Fiano, C. [Servicio de Anatomia Patologica, Hospital Xeral-Cies, Vigo (Spain)

    2001-06-01

    Insulinomas are pancreatic neoplasms that can be radiologically characterized typically because of their tendency to present intense and early contrast enhancement with a wash-out phenomenon. In this sense, we report an unusual case of a hypovascular solid pancreatic insulinoma confirmed with surgery and pathologic analysis, in a patient with normal serum insulin levels. In the two-phase helical CT, the mass behaved as a hypodense lesion with respect to the surrounding pancreatic parenchyma during the arterial phase and as a hypointense lesion during the dynamic contrast-enhanced MR imaging. Pathologic examination demonstrated a hypercellular tumor with poor vascularization of intervening stroma which showed prominent amyloid deposits. (orig.)

  3. Unusual presentation of a pancreatic insulinoma in helical CT and dynamic contrast-enhanced MR imaging: case report

    International Nuclear Information System (INIS)

    Iglesias, A.; Arias, M.; Brasa, J.; Casal, M.; Paramo, C.; Fiano, C.

    2001-01-01

    Insulinomas are pancreatic neoplasms that can be radiologically characterized typically because of their tendency to present intense and early contrast enhancement with a wash-out phenomenon. In this sense, we report an unusual case of a hypovascular solid pancreatic insulinoma confirmed with surgery and pathologic analysis, in a patient with normal serum insulin levels. In the two-phase helical CT, the mass behaved as a hypodense lesion with respect to the surrounding pancreatic parenchyma during the arterial phase and as a hypointense lesion during the dynamic contrast-enhanced MR imaging. Pathologic examination demonstrated a hypercellular tumor with poor vascularization of intervening stroma which showed prominent amyloid deposits. (orig.)

  4. Diagnosis and differential diagnosis of cerebro-vascular malformations by CT

    International Nuclear Information System (INIS)

    Schumacher, M.; Stoeter, P.; Voigt, K.

    1980-01-01

    In 38 patients, the diagnosis of a cerebrovascular malformation (17 arteriovenous angiomas including one low-flow- and two venous angiomas; 10 aneurysms; 4 arteriovenous fistulae of the cavernous sinus, the tentorium and one of the Great Vein of Galen; 6 megadolical basilar arteries) was initially made by computertomographic (CT) examination, including contrast enhancement. The characteristic and pathognomonic CT findings are described and compared with those of cerebral angiography also done in these cases. The problems of differential diagnosis and the reasons for a false CT diagnosis in 5 other patients with a cerebro-vascular malformation are investigated; and the diagnostic value of cerebral angiography and CT is discussed and their complementary functions are being pointed out. (orig.) 891 MG/orig. 892 MKO [de

  5. Xanthogranulomatous pyelonephritis in childhood: ultrasound and CT diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Cousins, C [City Hospital, Nottingham (United Kingdom); Somers, J [City Hospital, Nottingham (United Kingdom); Broderick, N [City Hospital, Nottingham (United Kingdom); Rance, C [City Hospital, Nottingham (United Kingdom); Shaw, D [Hospital for Sick Children, London (United Kingdom)

    1994-06-01

    Four cases of diffuse xanthogranulomatous pyelonephritis (XPN) in young children are presented. In three patients the clinical picture was one of weight loss, anaemia and neutrophilia with a large renal mass. The fourth presented with haematuria. Ultrasound (US) and CT findings were almost identical in all four patients. US showed the affected kidney was massively enlarged but retained a reniform shape. Dilated fluid spaces containing calculi were present. CT confirmed the US findings and revealed peripheral enhancement without contrast excretion, with dilated calyceal spaces producing the ''bear paw sign''. Extrarenal extension into abdominal wall and psoas muscle is typical and was well demonstrated by CT. The affected kidneys were non-functioning and nephrectomy was required. Typical US and CT features allow a confident diagnosis of XPN and appropriate early treatment. (orig.)

  6. Xanthogranulomatous pyelonephritis in childhood: ultrasound and CT diagnosis

    International Nuclear Information System (INIS)

    Cousins, C.; Somers, J.; Broderick, N.; Rance, C.; Shaw, D.

    1994-01-01

    Four cases of diffuse xanthogranulomatous pyelonephritis (XPN) in young children are presented. In three patients the clinical picture was one of weight loss, anaemia and neutrophilia with a large renal mass. The fourth presented with haematuria. Ultrasound (US) and CT findings were almost identical in all four patients. US showed the affected kidney was massively enlarged but retained a reniform shape. Dilated fluid spaces containing calculi were present. CT confirmed the US findings and revealed peripheral enhancement without contrast excretion, with dilated calyceal spaces producing the ''bear paw sign''. Extrarenal extension into abdominal wall and psoas muscle is typical and was well demonstrated by CT. The affected kidneys were non-functioning and nephrectomy was required. Typical US and CT features allow a confident diagnosis of XPN and appropriate early treatment. (orig.)

  7. Aneurysms of proximal pulmonary arteries: CT diagnosis and preoperative assessment

    International Nuclear Information System (INIS)

    Iula, G.; Ziviello, R.; Del Vecchio, W.

    1996-01-01

    We reviewed our experience with proximal pulmonary artery aneurysm (PPAA) to determine whether accurate preoperative evaluation (crucial to differential diagnosis and surgical planning) had been obtained on the basis of CT study alone. Three patients with PPAA were studied with contrast-enhanced CT. We evaluated the size and shape of PPAAs, their proximal and distal extent, eventual presence of intraluminal thrombi, dissection, perianeurysmal fibrosis, and rupture. The results were compared with surgical findings. In two patients the aneurysm involved the pulmonary trunk and both the right and left arteries origin. In one patient the aneurysm extended from the left artery origin to the hilum of the left lung. Contrast-enhanced CT alone allows detection of aneurysm in the pulmonary trunk, in right or left pulmonary arteries with precise preoperative evaluation of the extent, size, shape, and complications. The CT imaging was unable to establish the etiologic origin and presence of small intimal tears in PPAA. (orig.)

  8. Problems in CT diagnosis of the aging brain

    International Nuclear Information System (INIS)

    Kohlmeyer, K.

    1989-01-01

    The different methods of measuring the intracranial CSF spaces on CT images are described. The values obtained are demonstrated to separate the normal aging brain from the brain in senile dementia of Alzheimer's type. The CT criteria for the diagnosis of multiinfarctdementia are shown. The significance of CT studies in senile depression is discussed. The problem of vascular encephalopathy (leukoaraiosis) in normal aging of the brain and in dementia is considered in particular, and even the occurrence of intracranial space-occupying lesions and normal pressure hydrocephalus, as treatable causes of dementia and depression, are mentioned. The data and results of my own CT research on normal brain aging, dementia and depression are presented with reference to the literature. (orig.) [de

  9. CT diagnosis of congenital anomalies of the central nervous system

    International Nuclear Information System (INIS)

    Mori, Koreaki

    1980-01-01

    In the diagnosis of central nervous system congenital anomalies, understanding of embryology of the central nervous system and pathophysiology of each anomaly are essential. It is important for clinical approach to central nervous system congenital anomalies to evaluate the size of the head and tention of the anterior fontanelle. Accurate diagnosis of congenital anomalies depends on a correlation of CT findings to clinical pictures. Clinical diagnosis of congenital anomalies should include prediction of treatability and prognosis, in addition to recognition of a disease. (author)

  10. Clinical application of multi-slice helical CT volumetric scanning in lumber spine

    International Nuclear Information System (INIS)

    Wang Ling; Ge Yinghui; Zhu Shaocheng; Zhang Ming; Cheng Tianming; Lei Zhidan; Lv Chuanjian; Sun Xiaoping; Wu Minghui; Guo Ying; Ma Qianli; Wen Zeying

    2008-01-01

    Objective: To evaluate the clinical application value of multi-slice helical CT volumetric (VH) scanning in lumber spine. Methods: One thousand of patients with back and leg pain who underwent CT examinations were selected as subjects. We simulated the traditional protocol of single-slice(SS) discrete scanning for L3/4, L4/5, and L5/S1 intervertebral discs. The VH scanning mode was performed with 120 kV, 210 mAs, pitch of 1.5 and coverage of 97.5 mm. The simulated SS scanning mode was performed with 120 kV, 240 mAs and coverage of 45.0 mm. The diagnostic outcomes and the radiation doses were compared between the two scanning modes. Two groups doctors observed ten terms, including the osseous spinal stenosis, narrowed intervertebral space and so on in two scanning modes respectively. Then consistency analysis of the data was carded out. Results: The VH scanning mode showed far more features than the SS mode. The detection rates of the VH mode in the osseous spinal stenosis, narrowed intervertebral space, herniated nucleus pulposus, narrowed lateral recess, vertebral lesion, hypertrophy of L5 transverse process, abnormal direction of facet, facet degeneration, lumbar spondyloschisis, and paraspinal soft tissue were 11.8% (n=118), 38.5% (n=385), 9.3% (n=93), 46.8% (n=468), 31.4% (n=314), 5.7% (n= 57), 25.4% (n=254), 49.7% (n=497), 9.9% (n=99), and 0.6% (n=6) respectively, while the detection rates of the SS mode in ten terms were 5.6% (n=56), 0, 0.6% (n=6), 27.9% (n=279), 22.4% (n=224), 1.2% (n=12), 16.7% (n=167), 37.2% (n=372), 0.5% (n=5), and 0.2% (n=2) respectively. The difference between the two groups had statistically significance (average P 0.05). The detection rates of the VH mode were higher than the SS mode in the osseous spinal stenosis, narrowed intervertebral space, herniated nucleus pulposus, lumbar spondyloschisis, being 6.2% (n=62), 38.5% (n=385), 8.7% (n=87), and 9.4% (n=94), respectively. In addition, VH mode only partially showed the articular

  11. CT on diagnosis and differential diagnosis of adrenal neuroblastoma from nephroblastoma in children

    International Nuclear Information System (INIS)

    Han Jingtian; Shen Guoqiang; Yang Huayuan

    2000-01-01

    Objective: To evaluate the effect of CT on diagnosis and differential diagnosis of children's adrenal neuroblastoma from nephroblastoma. Materials and Method: To analyse the CT manifestations on 36 cases of adrenal neuroblastoma and 32 cases of nephroblastoma both confirmed by postoperative pathologic diagnosis. Results: The adrenal neuroblastoma is a kind of extrarenal tumor, so the kidney kept its original form and showed some compressive features. The incidence of tumor calcification appeared mostly in rough and speckle-piece form was high. While the nephroblastoma is a renal tumor. The surrounding renal parenchyma showed a specific 'new-moon shape' intensification. Conclusion: CT is one of the most valuable and effective means of examination to diagnose adrenal neuroblastoma and differentiate it from nephroblastoma. It can provide important information for making correct diagnosis, planning proper therapy and assessing prognosis

  12. A clinical study concerning hepatic arterial dominant phase and arrival time of contrast media on helical dynamic CT

    International Nuclear Information System (INIS)

    Matsubara, Susumu; Uchida, Chiharu; Sato, Sei; Ishida, Junichi; Masuya, Ryozo; Makiguchi, Mako; Kanamori, Isao

    2001-01-01

    Hepatic arterial dominant phase in helical dynamic CT was optimized by measuring the arrival time of contrast media (ATCM) with time-density curve (TDC). Subjects were 1005 patients (577 males and 428 females) and 98 nodules diagnosed as advanced hepatocellular carcinoma (HCC). The CT was done with Toshiba 4MHU X-vision SP, ultrasonography with Toshiba SSH-160A and automatic infusion of the contrast medium, iopamidol or iohexol, with Nemotokyorindo Autoenhance A-50. ATCM was found correlated with pulse rate and with arterial diameter, and significantly different between the sex. Elevation slope of TDC was suggested to be made constant by a defined infusion time of the dose corrected by body weight. Fluctuation of TDC among patients , when normalized by ATCM, was found smaller and the TDC was suggested to be useful for better imaging of HCC of less than 10 mm diameter. (K.H.)

  13. The wandering spleen: CT findings and possible pitfalls in diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Ben Ely, A.; Zissin, R.; Copel, L.; Vasserman, M.; Hertz, M.; Gottlieb, P.; Gayer, G

    2006-11-15

    Aim: To report the CT features of wandering spleen, a rare condition which can be incidentally detected as an abdominal or pelvic mass or can present with torsion, causing an acute abdomen. Materials and methods: The CT studies of seven patients, two children and five adults, with wandering spleen were reviewed. CT was performed urgently in three patients for acute abdomen, and electively in four. Results: CT findings of wandering spleen included absence of the spleen in its normal position and a mass located elsewhere in the abdomen or pelvis, i.e. an ectopic spleen, enhancing homogeneously in four cases and failing partially or completely to enhance in the other three, indicating infarction. A 'whirl' appearance representing the twisted splenic pedicle was seen in the three cases with torsion. Urgent splenectomy confirmed infarction secondary to torsion. Conclusion: The possible diagnosis of wandering spleen should be kept in mind when CT shows the spleen to be absent from its usual position and a mass is found elsewhere in the abdomen or pelvis. When, in addition, a 'whirl' or partial or no enhancement of this mass are seen in a case presenting with acute abdomen, torsion of a wandering spleen is a likely diagnosis.

  14. Diagnosis of pituitary adenoma by dynamic CT scanning

    International Nuclear Information System (INIS)

    Tanabe, Sumiyoshi; Uede, Teiji; Daibo, Masahiko; Niwa, Jun; Hashi, Kazuo

    1988-01-01

    The advantage of high resolution CT in the diagnosis of pituitary microadenomas has been established, but the diagnosis becomes more difficult when the pituitary microadenoma is less than 5 mm in diameter. We have studied the usefulness of dynamic CT scans particularly for diagnosis of small microadenomas. The dynamic CT scans were performed for 61 normal pituitary glands and 68 pituitary adenomas (36 microadenomas, 32 macroadenomas) with a GECT/T 9800 scanner. Coronal sections of 1.5 mm thickness were taken at the plane just in front of the pituitary stalk of the pituitary gland. Following a bolus intra-venous injection of 40 - 60 ml of contrast media using an automatic injector, ten consecutive CT scans of 2 seconds scan time were obtained, beginning 2 seconds from the start of intravenous injection. The first seven scans were taken with an interval of 2.3 seconds, and the last three scans with an interval of 10 seconds. Then, time-density curves were obtained at the ROI which were set on the anterior pituitary gland, the vascular bed of the pituitary gland, the pituitary stalk and the area of the pituitary adenoma respectively. In a normal pituitary gland, the density increases gradually and makes an S shaped curve, then attains the maximum density value (92.3 CT number) approximately 60 seconds after the administration of contrast media. The pituitary vascular bed is located in midline on the upper surface of the pituitary gland, and shows a symmetrical square, triangular or rhomboid shape. In case of pituitary adenoma, the time-density curve makes a plateau curve and attains the maximum density value (60.1 CT number) approximately 60 seconds after the administration of contrast media. In microadenoma, the pituitary vascular bed is either deformed or compressed, showing an asymmetrical shape. (author)

  15. Sinus cut-off sign: A helpful sign in the CT diagnosis of diaphragmatic rupture associated with pleural effusion

    International Nuclear Information System (INIS)

    Kaya, Seyda Ors; Karabulut, Nevzat; Yuncu, Gokhan; Sevinc, Serpil; Kiroglu, Yilmaz

    2006-01-01

    The objective of our study was to describe the 'sinus cut-off' sign at CT in the diagnosis of diaphragmatic rupture in patients with blunt abdominal trauma complicated with pleural effusion, and evaluate its utility in an experimental model. Between January 2004 and March 2005, we observed an unusual interruption of costophrenic sinus at CT in three patients with blunt abdominal trauma accompanied with pleural effusion. This observation prompted us to evaluate the utility of this sign in an experimental model. Laparotomically, we created 2 cm diapragmatic lacerations at each hemidiaphragm in two rabbits and pushed up the abdominal viscera with omentum through the defect. To simulate hemothorax, we also injected 5-10 mL of diluted contrast material into the pleural space. Using a dual-slice helical CT scanner, limited thoracoabdominal CT examination was performed before and after injection of intrapleural contrast material. The images were analyzed for the presence of CT signs for diaphragmatic injury. The left posterior costophrenic sulcus was interrupted in all of the three patients with left pleural effusion. While it was associated with other findings of diaphragmatic injury, the 'sinus cut-off sign' was the sole finding in one patient. The sinus cut-off sign was observed on the CT scans of 100% of the rabbits with a left and right sided diaphragmatic rupture. The 'sinus cut-off sign' is useful and can increase the CT detection of acute diaphragmatic injury associated with pleural effusion

  16. The prevalence of erosive osseous changes of the articular eminence in the temporomandibular joint in patients with mandibular prognathism without internal derangement. MR and helical CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, Takafumi; Ito, Jusuke; Tanaka, Rei; Koyama, Jun-ichi; Kobayashi, Fukiko [Niigata Univ. (Japan). Graduate School of Medical and Dental Sciences

    2002-06-01

    The aim of this study was to assess the prevalence of erosive osseous changes of the articular eminence in the temporomandibular joint without internal derangement. Sixty joints of 30 consecutive patients with mandibular prognathism were evaluated with both MR imaging and helical CT. On MPR images obtained with helical CT, erosive osseous changes of the articular eminence were observed in 18 joints (30%) of 13 patients. None of the joints studied demonstrated an osseous change in the mandibular condyle. MR imaging failed to detect erosive osseous changes of the articular eminence in all of the joints studied. In conclusion, MPR images obtained with helical CT were of value to detect erosive osseous changes of the articular eminence. (author)

  17. The prevalence of erosive osseous changes of the articular eminence in the temporomandibular joint in patients with mandibular prognathism without internal derangement. MR and helical CT findings

    International Nuclear Information System (INIS)

    Hayashi, Takafumi; Ito, Jusuke; Tanaka, Rei; Koyama, Jun-ichi; Kobayashi, Fukiko

    2002-01-01

    The aim of this study was to assess the prevalence of erosive osseous changes of the articular eminence in the temporomandibular joint without internal derangement. Sixty joints of 30 consecutive patients with mandibular prognathism were evaluated with both MR imaging and helical CT. On MPR images obtained with helical CT, erosive osseous changes of the articular eminence were observed in 18 joints (30%) of 13 patients. None of the joints studied demonstrated an osseous change in the mandibular condyle. MR imaging failed to detect erosive osseous changes of the articular eminence in all of the joints studied. In conclusion, MPR images obtained with helical CT were of value to detect erosive osseous changes of the articular eminence. (author)

  18. CT diagnosis of traumatic bronchial rupture in children

    International Nuclear Information System (INIS)

    Epelman, Monica; Ofer, Amos; Guralnik, Ludmila; Klein, Yoram; Best, Leal H.; Bentur, Lea; Traubici, Jeffrey

    2002-01-01

    Bronchial rupture is a rare and serious complication of blunt chest trauma in children. The diagnosis of this injury is challenging and requires a high degree of clinical suspicion. It is frequently associated with other severe injuries that may draw the focus of attention away from this potentially catastrophic but treatable injury. The radiographic findings of bronchial rupture have been reported in very few series. We report the findings in two children with bronchial rupture diagnosed by CT, in whom CT resulted in a significant change in patient management. (orig.)

  19. The diagnosis of internal disc disruption with CT discography

    International Nuclear Information System (INIS)

    Liu Miao; Chen Xingcan; Li Xiaohong; Pan Yongqin

    2008-01-01

    Objective: To study the value of diagnosis for internal disc disruption (IDD)with CT discography(CTD). Methods: 42 discs of 32 patients showing no disc herniation on CT or MRI, but suffering from chronic low back pain, were undertaken CTD to work out the types of CTD with correlation between contrast medium dosages and the induction of pain. Results: CTD demonstrated 4 types of IDD which was individually correlated with the contrast dosages and induced pain; furthermore the dosages for positive and negative disc cases showed significant differece (P<0.01). Conclusions: CTD can show the direct sign of internal disc disruption, providing more information than conventional discography. (authors)

  20. Preliminary evaluation of helical CT colonography in detection of colonic diseases compared with double contrast barium enema

    International Nuclear Information System (INIS)

    Zhai Xiaoli; Zhang Lei; Zhai Renyou; Li Jie; Wang Yajie; Ding Yi

    2000-01-01

    Objective: To evaluate helical CT colonography in regard to technology principles, limitations, and clinical applications. Methods: Fifty-six patients underwent volume scanning using helical CT. The diseases included adenocarcinoma 39, adenomatous polyp 3, multiple diverticular 7, mucocele of appendix 1, and normal colon 6. All cases had been compared with double contrast barium enema (DCBE), proved by histology except the 6 normal colon and the 7 multiple diverticular. All CTC images were reconstructed using shaded surface display (SSD) on workstation. Then, perspective images such as the ones from DCBE were generated via ray sum. The images could clearly demonstrate the extent and detail of the disorder by using 'CUT' software, 'revolve' function, and zoom. Results: CTC correctly demonstrated 3-5 mm diverticulum, 3 mm ulcer, and 6 mm polyps. Not only show colon straitness clearly, CTC is also very sensitive to demonstrate the stenotic end of masses. In these cases, discovery rate of CTC is 100.0%, the rate of DCBE is 88.6%; CTC is more sensitive than DCBE in cases of tumor nodules. Ray sum can show the boundary of colonic mass extending to both proximal and distal ends, its discovery rate is 62.6%. Accuracy of localization for CTC is 100.0%. Conclusion: CTC is a novel technique for detecting colonic diseases. It is a safe, accurate, and non-invasive means for detection of lesions and is an efficient complement for DCBE. Further development in CTC technique is expected in the future

  1. CT diagnosis of the primary lung cancer and usefulness of biopsy under CT

    International Nuclear Information System (INIS)

    Fujisawa, Hidefumi; Kushihashi, Tamio

    2011-01-01

    CT especially plays an important role in imaging diagnosis of lung cancer (LC) which gives quite multiple CT findings and this paper describes details to be noted for CT findings of individual lung lesion and cancer according to 5 classes below, together with usefulness of CT-guided biopsy and positron emission tomography (PET) usage. Explained are as follows: Important points in histopathology and CT findings from adenomatous hyperplasia (AH) to atypical AH (pre-invasive lesion); Differential CT diagnosis of benignity or malignancy of pulmonary nodes and tumors; Typical CT findings of LC of peripheral type of invasive or exclusive proliferative type, and pulmonary hillar type; Atypical CT findings of LC/having atypical inner structure such as presenting atypical calcification and atypical cavity/having atypical morphology such as presenting pneumonia-like finding, exhibiting regular or linear edge, and existing at atypical region like extrapleural lumen /having atypical progression rate such as showing rapid or slow doubling time of the volume and shrinking tentatively during the progress/of juvenile LC/and generated from background lung diseases such as interstitial pneumonia, tuberculosis, pneumoconiosis like asbestosis, pneumosilicosis, and pulmonary emphysema and bulla; and Regional ground glass opacity. As well, authors mention about the usefulness of CT-guided needle biopsy of the pulmonary lesion which enables to take the nodal specimen as small as <10 mm. Most frequent complication of the biopsy is pneumothorax (10-50%). How to use PET for LC examination is also commented with its usability and limitation. (T.T.)

  2. Pulmonary sequestration: diagnosis with three dimensional reconstruction using spiral CT

    International Nuclear Information System (INIS)

    Nie Yongkang; Zhao Shaohong; Cai Zulong; Yang Li; Zhao Hong; Zhang Ailian; Huang Hui

    2003-01-01

    Objective: To evaluate the role of three dimensional (3D) reconstruction using spiral CT in the diagnosis of pulmonary sequestration. Methods: Ten patients with pulmonary sequestration were analyzed. The diagnoses were confirmed by angiography in 2 patients, by operation in 2 patients, and by CT angiography in 6 patients. All patients were examined with Philips SR 7000 or GE Lightspeed Plus scanner. CT images were transferred to a workstation and 3D reconstruction was performed. All images were reviewed and analyzed by two radiologists. Results: Among 10 patients, the pulmonary sequestration was in the right lower lobe in 1 patient and in the left lower lobe in 9 patients. Anomalous systemic arteries originated from thoracic aorta in 8 patients and from celiac artery in 2 patients. On plain CT scan, there were 4 patients with patchy opacities, 3 patients with hilar mass accompanying vascular engorgement and profusion in adjacent parenchyma, 2 patients with finger-like appendage surrounded by hyper-inflated lung, and 1 patient with lung mass-like lesion. Enhanced CT revealed anomalous systemic arteries in 9 patients and drainage vein in 7 patients. Maximum intensity projection (MIP) and curvilinear reconstruction could depict the abnormal systemic artery and drainage vein in sequestration. Surface shadow display (SSD) and volume rendering (VR) could delineate the anomalous systemic artery. Conclusion: 3D reconstruction with enhanced spiral CT can depict anomalous systemic artery and drainage vein and it is the first method of choice in diagnosing pulmonary sequestration

  3. Helical CT for lung-cancer screening. 3. Fundamental study for ultra-low-dose CT by application of small tube current and filter

    International Nuclear Information System (INIS)

    Itoh, Shigeki; Koyama, Shuji; Tusaka, Masatoshi; Maekoshi, Hisashi; Satake, Hiroko; Ishigaki, Takeo.

    1996-01-01

    In order to develop ultra-low-dose helical CT for lung cancer screening, the effect of reduction of the tube current to 20 mA and application of a 10 mm thick aluminium filter upon radiation dose and image quality was evaluated with a phantom. Exposure dose at the center of a gantry and absorbed dose at the center of an acrylic phantom at 20 mA with the filter were 15% and 29% of the dose at 50 mA without the filter, respectively. For reduction of absorbed dose, reduction of the tube current was more useful than application of the filter. Image noise at 20 mA with the filter was double that at 50 mA without the filter. Neither reduction of the tube current nor application of the filter changed full width at half maximum on section sensitivity of the Z-axis. Although reduction of the tube current did not affect the difference in CT values between an acrylic sphere and styroform, application of the filter caused a reduction of 4.5% in the difference in CT values. Neither reduction of the tube current nor application of the filter affected the contrast resolution of the high-contrast phantom; however, that of the low-contrast phantom deteriorated. Although improvement of the filter and evaluation of clinical images are necessary, reduction of the tube current to 20 mA and application of the aluminium filter appear to be a promising method for ultra-low-dose helical CT of the lung. (author)

  4. How to choose PET-CT or CT in the diagnosis and staging of lung cancer. Practical experience in China

    International Nuclear Information System (INIS)

    Jiang, T.; Tao, X.; Liu, H.; Liu, S.; Zheng, X.

    2010-01-01

    How to use CT and PET-CT rationally to raise diagnosis, staging and prognostic assessment of lung cancer to a higher level at the best cost-effect ratio is a subject that Chinese clinicians and radiologists should face conscientiously. We review the rational application of CT and PET-CT in four aspects of lung cancer, including screening and detection, morphologic evaluation, haemodynamic or metabolic feature evaluation, and follow-up, staging and prognostic evaluation. As PET-CT is only available in class III-A hospitals today, CT is the most popular equipment in China. PET-CT is more valuable only in cases where CT presentation of lung cancer is atypical or difficult to determine, or in cases where the diagnosis of lung cancer has been initially confirmed, for which clinical staging and decision concerning on therapeutic regimens are needed. We also recommend the current strategies of CT and PET-CT managing of SPN in China. (orig.)

  5. Usefulness of CT in the diagnosis and management of acute abdomen

    International Nuclear Information System (INIS)

    Suzuki, Takuya; Matsumoto, Junichi; Funakubo, Masakatsu; Yamashita, Hirotaka; Ehara, Norishige; Minowa, Yoshiyuki; Nakajima, Yasuo

    2010-01-01

    We prospectively evaluated the usefulness of computed tomography (CT) in the diagnosis and management of acute abdomen. Ninety-four patients with acute abdomen were enrolled. We compared the final diagnosis and management CT diagnosis and management. Then, we evaluated how many of the CT examinations were useful and the degree to which they were useful. In more than 90% of cases, CT was very useful for the diagnosis and management of acute abdomen. (author)

  6. Early clinical phase of patient's management after polytrauma using 1- and 4-slice helical CT; Fruehes klinisches Management nach Polytrauma mit 1- und 4-Schicht-Spiral-CT

    Energy Technology Data Exchange (ETDEWEB)

    Kloeppel, R.; Kahn, T. [Klinik und Poliklinik fuer Diagnostische Radiologie, Universitaetsklinikum Leipzig (Germany); Schreiter, D. [Chirurgische Intensivtherapieabteilung, Zentrum fuer Chirurgie, Universitaetsklinikum Leipzig (Germany); Dietrich, J. [Abt. Neuroradiologie der Klinik und Poliklinik fuer Diagnostische Radiologie, Universitaetsklinikum Leipzig (Germany); Josten, C. [Klinik und Poliklinik fuer Unfall- und Wiederherstellungschirurgie, Zentrum fuer Chirurgie, Universitaetsklinikum Leipzig (Germany)

    2002-07-01

    In the early clinical phase the comprehensive imaging of patients with multiple trauma using helical CT is already established. Aim of this study was to assess whether MSCT may improve the patient management and the diagnostic results.The procedure is designed as follows: after life-thretening treatment x-ray of chest and ultrasound are carried out in the emergency room. Then the patient is moved to CT. From 1998 to december 2000 241 patients were examined using a single slice helical CT (Somatom plus 4), in 2001 79 patients using a 4-slice helical CT (Somatom VZ, Siemens Med.Sol.). After CT selected radiograms of the extremities were taken.359 of 360 procedures were carried out successfully. Excluding 1 case (death during 1-sl. h CT) all relevant lesions of head, neck, and body were diagnosed. Although the patients had an injury severity score of {approx}30. The change from 1slice-helical CT to 4 slice-helical CT allowed us to reduce the stay in the CT room from 28 to 16 min. The total lethality decreased by {approx}4%.Advantages for the patient arose from the standardized examination protocol using multislice CT. If integrated in an interdisciplinary management concept, it is a good compromise between examination time, comprehensive diagnostic imaging, life-saving therapeutic procedures, and therapy planning. (orig.) [German] Die klinische Erstversorgung Polytraumatisierter schliesst inzwischen in vielen Unfallkliniken den fruehzeitigen Einsatz der Spiral-CT ein. Kann die neuerlich eingefuehrte Mehrschicht-Spiral-CT Ergebnisse und Patientenmanagement weiter verbessern?Nach lebensrettenden Sofortmassnahmen, Thoraxroentgen und Notsonographie im Schockraum erfolgte die CT: Von 1998-2000 wurden 241 Patienten mit einem 1-Schicht-Spiral-CT (Somatom plus 4) und in 2001 79 Patienten mit einem 4-Schicht-Spiral-CT (Somatom VZ, beide Siemens Med. Sol.) untersucht. Klinisch ausgewaehlte Extremitaetenaufnahmen wurden ergaenzt.359 von 360 Untersuchungen verliefen erfolgreich

  7. Ultrasonography, CT, and ERCP in the diagnosis of choledochal stones

    International Nuclear Information System (INIS)

    Pasanen, P.; Partanen, K.; Pikkarainen, P.; Alhava, E.; Pirinen, A.; Janatuinen, E.

    1992-01-01

    A prospective study of jaundiced (n = 187) and nonjaundiced (n = 33) cholestatic patients was carried out to evaluate the sensitivity of ultrasonography (US), CT and endoscopic retrograde cholangiopancreatography (ERCP) in the detection of choledochal stone disease. Altogether 83 patients had the final diagnosis of choledocholithiasis. In the jaundiced patients, the sensitivity of US, CT, and ERCP was 22,5%, 23,2%, and 80,6%, respectively. In cases of cholestasis without jaundice, the values were 20%, 37,5%, and 66,7%. In patients in whom all 3 imaging studies were done (n = 64), the differences between US and ERCP and between CT and ERCP were statistically significant (p < 0.0001). In most false-negative ERCP studies (10/15), the clinical course of the disease strongly suggested a passed choledochal stone. On the basis of this study, we recommend prompt ERCP to be performed if choledochal stone disease is suspected on clinical grounds. (orig.)

  8. A three-dimensional-weighted cone beam filtered backprojection (CB-FBP) algorithm for image reconstruction in volumetric CT-helical scanning

    International Nuclear Information System (INIS)

    Tang Xiangyang; Hsieh Jiang; Nilsen, Roy A; Dutta, Sandeep; Samsonov, Dmitry; Hagiwara, Akira

    2006-01-01

    Based on the structure of the original helical FDK algorithm, a three-dimensional (3D)-weighted cone beam filtered backprojection (CB-FBP) algorithm is proposed for image reconstruction in volumetric CT under helical source trajectory. In addition to its dependence on view and fan angles, the 3D weighting utilizes the cone angle dependency of a ray to improve reconstruction accuracy. The 3D weighting is ray-dependent and the underlying mechanism is to give a favourable weight to the ray with the smaller cone angle out of a pair of conjugate rays but an unfavourable weight to the ray with the larger cone angle out of the conjugate ray pair. The proposed 3D-weighted helical CB-FBP reconstruction algorithm is implemented in the cone-parallel geometry that can improve noise uniformity and image generation speed significantly. Under the cone-parallel geometry, the filtering is naturally carried out along the tangential direction of the helical source trajectory. By exploring the 3D weighting's dependence on cone angle, the proposed helical 3D-weighted CB-FBP reconstruction algorithm can provide significantly improved reconstruction accuracy at moderate cone angle and high helical pitches. The 3D-weighted CB-FBP algorithm is experimentally evaluated by computer-simulated phantoms and phantoms scanned by a diagnostic volumetric CT system with a detector dimension of 64 x 0.625 mm over various helical pitches. The computer simulation study shows that the 3D weighting enables the proposed algorithm to reach reconstruction accuracy comparable to that of exact CB reconstruction algorithms, such as the Katsevich algorithm, under a moderate cone angle (4 deg.) and various helical pitches. Meanwhile, the experimental evaluation using the phantoms scanned by a volumetric CT system shows that the spatial resolution along the z-direction and noise characteristics of the proposed 3D-weighted helical CB-FBP reconstruction algorithm are maintained very well in comparison to the FDK

  9. CT findings and differential diagnosis of cystic neck masses

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    Lee, Ji Yeon; Lee, Kil Jun; Jeong, Seong Ki; Han, Seong Nim; Tae, Seok; Shin, Kyoung Ja; Lee, Sang Chun [Seoul Red Cross Hospital, Seoul (Korea, Republic of)

    1995-10-15

    The purpose of this study is to analyze the CT features of the cystic masses in the neck and to review differential diagnosis. We retrospectively reviewed and analyzed the CT findings of 22 histopathologically proved, cystic neck masses in regard to the location in fascial plane and relationship with adjacent organ. Of 22 cases, ten congenital cysts two ranulas, seven inflammatory lesions, and three solid tumors were included. Ten congenital cystic masses were located in typical locations as branchial cleft cyst (5) in mandibular angle, thyroglossal duct cyst (3) in visceral space embeded within the strap muscles, cystic hygroma (1) and cavernous hemangioma (1) in posterior cervical space with insinuating appearance. Two cases of ranula included one simple ranula localized in sublingual space and a plunging ranula extending to adjacent submandibular space. Seven cases of inflammatory lesions were characterized by multispatial locations and good contrast-enhancement of walls and adjacent tissue. Solid masses of low density mimicking cyst were two pleomorphic adenomas of submandibular gland and one neurilemmoma. It is considered that thorough analysis of the CT findings with attention to typical location, CT appearance, and the relationship with the adjacent structures usually leads to the correct diagnosis.

  10. Multi-slice spiral CT diagnosis of carotid body tumor

    International Nuclear Information System (INIS)

    Li Peiling; Leng Renli; Li Shu; Xie Xiuli; Xu Ke

    2006-01-01

    Objective: to explore the Multi-slice spiral CT (MSCT) findings of carotid body tumor (CBT). Methods: Twelve cases of CBT proved by surgery were collected in this study and all patients accepted contrast-enhanced MSCT examination. Two-dimensional and three-dimensional post-processing were performed at diagnostic workstation using Aquilion 1.42. The CT features of CBT were analyzed. Results Each of 12 patients had one lesion. All lesions demonstrated well-marginated masses of homogeneous soft- tissue density with CT value within 29-48 HU on pre-enhanced images. All lesions were markedly enhanced with CT value over 200 HU on arterial-phase images, and the density of lesions decreased rapidly on delay- phase images. Twelve lesions were all located at the level of carotid artery bifurcation, 3 of them enveloping common carotid artery and internal/external carotid artery, and other 9 of them riding right on the carotid bifurcation. Internal carotid artery usually were shifted toward posterior-lateral, and external carotid artery toward anterior or anterior-medial. Conclusion: Contrast-enhanced MSCT examination not only can make a qualitative diagnosis of CBT, but determine its accurate location. It plays an importantly instructional role in clinical diagnosis and treatment. (authors)

  11. Improved CT imaging in diagnosis of ankylosing spondylitis

    International Nuclear Information System (INIS)

    Mai Yuanfeng; Sun Haixing; Ling Jian; Kuang Jianyi; Pan Ximin

    2006-01-01

    Objective: To evaluate the improved CT imaging of sacroiliac joint in diagnosis of ankylosing spondylitis (AS). Methods: 22 patients, diagnosed as AS by clinical and radiography, undertook both conventional and improved CT imaging. All images were comparatively studied. Results: With conventional CT imaging, in the 44 joints of 22 cases, unremarkable images were obtained in 3 cases; early stage AS was found in 15 joints of 9 cases; AS in progressive stage was revealed in 8 cases/16 joints, stabled AS was presented in 2 cases/4 joints. There were 23 joints in 12 cases diagnosed as early term by improved imaging, progressive staged AS was shown in 8 cases/16 joints as, stable AS was demonstrated in 2 cases/4 joints. Conclusion: The improved imaging is sensitive in the diagnosis of early staged AS, for the application of thin slice scan, which helps to reduce partial volume effect. Scanning along the longitudinal axis of the sacroiliac joint extends the observation of erosion of the joint surface. For progressive or stable staged AS, the alterations of bone and joint space are prominent, improved CT imaging is not superior to the conventional. (authors)

  12. CT diagnosis of pancreatitis and carcinoma of the pancreas

    International Nuclear Information System (INIS)

    Sager, W.D.; Nedden, D. zur; Lepuschuetz, H.; Zalaudek, G.; Bodner, E.; Fotter, R.; Lammer, J.; Innsbruck Univ.; Graz Univ.; Innsbruck Univ.

    1981-01-01

    The article reports on 78 CT scans of surgically diseases of the pancreas, 30 cases of chronic pancreatitis, 12 cases of haemorrhagic-necrotizing pancreatitis, and 36 cases of carcinoma of the pancreas. 12 of these cases were operable, whereas 234 were inoperable. The operable carcinomas were so small that proper diagnosis was effected in 50% only, whereas the inoperable carcinomas eluded CT identification in 17% of the cases only. The most important signs of an operable carcinoma of the pancreas are a well-defined enlargement and inhomogeneity of the parenchyma with reduced contrast, especially on bolus injection, as well as dilatation of the bile duct system. The most essential criteria for inoperability are absence of boundaries, especially towards the dorsal side, with infiltration of the retroperitoneal fatty tissue, and lack of delineation of the large vessels. According to the present state of the art, CT does not supply definite criteria for differentiating between an operable carcinoma of the pancreas and chronic fibrotic pancreatitis. Overstepping of the marginal contours is a reliably distinctive feature between carcinoma and pancreatitis, but it also points to the inoperable nature of the disease. Haemorrhagic-necrotizing pancreatitis is characterized by definite CT criteria, so that diagnosis is easy. Computerised tomography is a valuable diagnostic tool in diseases of the pancreas and can supply conclusive pointers towards the operability of a tumor. (orig.) [de

  13. CT quantitative diagnosis in fatty liver. An experimental study

    International Nuclear Information System (INIS)

    Zhao Hong; Li Binxiang; Zhang Lizhong; Liang Jianfang

    1997-01-01

    Purpose: To evaluate the relation between liver fat content and CT value in animal experiment for the diagnosis and treatment of fatty liver in clinical practice. Materials and methods: Fatty liver model was established in 30 Wistar rats (experimental group), 5 rats was used as the control group. The 5 rats of the control group and 5 rats randomly chosen from experimental group at the first, second, third, and the fourth weekends, were measured for the CT number of total liver. Three pieces of liver specimen from each rats were removed from left, central and right lobes for histologic examination. The ratio of liver fat content to liver volume (Vv value) was measured by microscopic image pattern analyzer. Results: Significant linear negative correlation (r = -0.950, t = 12.90, P<0.001) was found between CT and Vv values. Conclusion: Using CT monitoring, the degree and amount of liver fat could be assessed and liver biopsy obviated in the diagnosis and follow up during treatment of fatty liver

  14. Diagnosis of small hepatocellular carcinoma by incremental dynamic CT

    International Nuclear Information System (INIS)

    Uchida, Masafumi; Kumabe, Tsutomu; Edamitsu, Osamu

    1993-01-01

    Thirty cases of pathologically confirmed small hepatocellular carcinoma were examined by Incremental Dynamic CT (ICT). ICT scanned the whole liver with single-breath-hold technique; therefore, effective early contrast enhancement could be obtained for diagnosis. Among the 30 tumors, 26 were detected. The detection rate was 87%. A high detection rate was obtained in tumors more than 20 mm in diameter. Twenty-two of 26 tumors could be diagnosed correctly. ICT examination was useful for detection of small hepatocellular carcinoma. (author)

  15. CT and MRI diagnosis of acute hepatic injury

    International Nuclear Information System (INIS)

    Wang Rengui; Fumio Yamamoto; Pu Yonglin; Gao Yujie.

    1997-01-01

    To evaluate and compare MR and CT in diagnosis of acute traumatic hepatic laceration, ten patients with acute hepatic rupture underwent CT scan and/or MRI in the first 24 hours after injury. The injury was graded as mild ( 50% of one lobe). In the first 24 hours after injury, 33.3% (3/9) and 28.6%(2/7) of the hepatic injury demonstrated isodensity and isointensity on plain CT scan and T 1 -weighted images. All the lesions (100%) were clearly identified as marked hyperintensity on T 2 -weighted images. On T 2 WI, T 1 WI and non-contrast CT, 100%, 57.1% and 55.6% of the acute hepatic injuries could be graded respectively. Delayed complications occurred in four patients with deep hepatic injury about 1 to 3 weeks after injury. T 2 -weighted MR imaging is more sensitive and useful for detection of the type and severity of acute hepatic rupture. Follow-up MRI or CT within the first few weeks after injury is needed in patients with deep hepatic injury for detection of delayed complications

  16. CT and MRI diagnosis of tubo-ovarian masses

    International Nuclear Information System (INIS)

    Xiong Minghui; Zhang Wanshi; Wang Dong

    2000-01-01

    Objective: To evaluate the diagnostic value of CT and MRI in tubo-ovarian masses. Methods: CT scan was performed in 67 patients with tubo-ovarian masses confirmed by pathology. 19 of them underwent MRI. Results: (1) 20 primary malignant ovarian tumors showed cystic,solid or cystic-solid masses; papillary projections on cystic wall; pelvic organs and pelvic wall invasion. Chocolate cysts with malignant degeneration exhibited small nodules on thickened cystic wall on CT and MRI. T 1 WI was better for revealing the lesions. (2) Of 11 cases of metastasis to tubo-ovary, 4 showed peritoneal linear enhancement. (3) There were 9 cystadenomas and 2 adenofibromas, one of the cystadenomas contained fat, two adenofibromas were similar to uterus in density on CT while showing lower signal intensity on MRI (both T 1 WI and T 2 WI). (4) Three cases of thecoma exhibited cystic or solid masses, solid thecomas revealed granular enhancement. (5) Teratomas were most specific, one of them was associated with thecoma. (6) Tubo-ovarian abscesses and tuberculosis depicted cystic or cystic-solid masses. (7) Two cases of tubal pregnancy showed inhomogeneous soft tissue masses, the lower density areas in the centers were clot and organized tissues confirmed by pathology. Conclusion: (1) CT and MRI had higher sensitivity but lower specificity for tubo-ovarian masses, the diagnosis should be combined with clinical history and patients' age. (2) Tumors of two different types may coexist and sometimes fat may be present in tumors other than teratoma

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

    International Nuclear Information System (INIS)

    Wang Jue; Wang Fuquan; Jiang Zenghui

    2008-01-01

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

  18. 3D-CT angiography with ultrafast CT in the diagnosis of pulmonary thromboembolism

    International Nuclear Information System (INIS)

    Kuribayashi, Sachio; Hamada, Seiki; Takamiya, Makoto; Imakita, Satoshi; Yamada, Naoaki; Takase, Kei; Iino, Misako; Nakanishi, Norifumi

    1995-01-01

    The usefulness of 3D-CT angiography (3D-CTA) with ultrafast CT (UFCT) in the diagnosis of pulmonary thromboembolism (PTE) was evaluated. UFCT was carried out in 10 patients with PTE (acute: 5 cases, chronic: 5 cases) and one case with pulmonary artery thrombosis secondary to pulmonary hypertension with atrial septal defect. CT scanning was performed with Imatron C-100XL and C-150L. For the imaging, single-slice step volume scan mode was used with scan time of 100 msec and slice thickness of 6 mm. Contiguous axial images were obtained after contrast enhancement with slice interval of 6 mm. 3D-CTA was reconstructed from 2D-CT images with workstation, and was compared with pulmonary angiograms (PAG) or operative findings. The images of 3D-CTA had good quality and they were more useful than 2D-CT images in better understanding of the configuration and the extent of the thrombi. In comparison with PAG, 3D-CTA gave equivalent information in terms of central pulmonary emboli. Moreover, 3D-CTA had advantages over PAG in demonstrating both the blood lumen and the thrombus on the same image with capability of multi-directional displays. 3D-CTA with UFCT is the useful non-invasive imaging modality in the diagnosis of PTE. (author)

  19. A BPF-FBP tandem algorithm for image reconstruction in reverse helical cone-beam CT

    International Nuclear Information System (INIS)

    Cho, Seungryong; Xia, Dan; Pellizzari, Charles A.; Pan Xiaochuan

    2010-01-01

    Purpose: Reverse helical cone-beam computed tomography (CBCT) is a scanning configuration for potential applications in image-guided radiation therapy in which an accurate anatomic image of the patient is needed for image-guidance procedures. The authors previously developed an algorithm for image reconstruction from nontruncated data of an object that is completely within the reverse helix. The purpose of this work is to develop an image reconstruction approach for reverse helical CBCT of a long object that extends out of the reverse helix and therefore constitutes data truncation. Methods: The proposed approach comprises of two reconstruction steps. In the first step, a chord-based backprojection-filtration (BPF) algorithm reconstructs a volumetric image of an object from the original cone-beam data. Because there exists a chordless region in the middle of the reverse helix, the image obtained in the first step contains an unreconstructed central-gap region. In the second step, the gap region is reconstructed by use of a Pack-Noo-formula-based filteredbackprojection (FBP) algorithm from the modified cone-beam data obtained by subtracting from the original cone-beam data the reprojection of the image reconstructed in the first step. Results: The authors have performed numerical studies to validate the proposed approach in image reconstruction from reverse helical cone-beam data. The results confirm that the proposed approach can reconstruct accurate images of a long object without suffering from data-truncation artifacts or cone-angle artifacts. Conclusions: They developed and validated a BPF-FBP tandem algorithm to reconstruct images of a long object from reverse helical cone-beam data. The chord-based BPF algorithm was utilized for converting the long-object problem into a short-object problem. The proposed approach is applicable to other scanning configurations such as reduced circular sinusoidal trajectories.

  20. Appendicitis and alternate diagnoses in children: findings on unenhanced limited helical CT

    International Nuclear Information System (INIS)

    Lowe, L.H.; Perez, R. Jr.; Scheker, L.E.; Stein, S.M.; Heller, R.M.; Hernanz-Schulman, M.

    2001-01-01

    The objective of this manuscript is to review and illustrate the findings of appendicitis, and of alternate diagnoses that may clinically or radiographically simulate appendicitis, on unenhanced limited CT in children. Potential pitfalls in unenhanced limited CT interpretation of pediatric patients will also be discussed. (orig.)

  1. Volume doubling time and growth rate of renal cell carcinoma determined by helical CT: a single-institution experience

    International Nuclear Information System (INIS)

    Lee, Ji Young; Kim, Chan Kyo; Choi, Dongil; Park, Byung Kwan

    2008-01-01

    The purpose of this study was to retrospectively evaluate the volume doubling time (VDT) and growth rate of renal cell carcinomas (RCC) on a serial computed tomography (CT) scan. Thirty pathologically proven RCCs were reviewed with helical CT. Each tumor underwent at least two CT scans. Tumor volume was determined using an area measuring tool and the summation-of-areas technique. Growth rate was evaluated in terms of diameter and volume changes. VDT and volume growth rate were compared in relation to several factors (initial diameter, initial volume, diameter growth rate, volume growth rate, tumor grade, tumor subtype, sex or age). Mean VDT of RCCs was 505 days. Mean diameter and volume growth rate were 0.59 cm/year and 19.1 cm 3 /year, respectively. For volume and diameter growth rate, tumors ≤4 cm showed lower rates than those >4 cm (P 0.05). Volume growth rate was moderately to strongly positively correlated with initial diameter, initial volume and diameter growth rate (P < 0.05). In conclusion, small RCCs grew at a slow rate both diametrically and volumetrically. More accurate assessment of tumor growth rate and VDT may be helpful to understand the natural history of RCC. (orig.)

  2. Low-dose helical computed tomography (CT) in the perioperative workup of adolescent idiopathic scoliosis

    Energy Technology Data Exchange (ETDEWEB)

    Abul-Kasim, Kasim; Overgaard, Angelica; Maly, Pavel [Malmoe University Hospital, Department of Radiology, Section of Neuroradiology, University of Lund, Malmoe (Sweden); Ohlin, Acke [Malmoe University Hospital, Department of Orthopaedic Surgery, University of Lund, Malmoe (Sweden); Gunnarsson, Mikael [Malmoe University Hospital, Department of Radiation Physics, University of Lund, Malmoe (Sweden); Sundgren, Pia C. [University of Michigan Health Systems, Department of Radiology, Division of Neuroradiology, Ann Arbor (United States)

    2009-03-15

    The study aims were to estimate the radiation dose in patients examined with low dose spine CT and to compare it with that received by patients undergoing standard CT for trauma of the same region, as well as to evaluate the impact of dose reduction on image quality. Radiation doses in 113 consecutive low dose spine CTs were compared with those in 127 CTs for trauma. The inter- and intraobserver agreement in measurements of pedicular width, and vertebral rotation, measurements of signal-to-noise ratio and assessment of hardware status were the indicators in the evaluation of image quality. The effective dose of the low dose spine CT (0.37 mSv) was 20 times lower than that of a standard CT for trauma (13.09 mSv). This dose reduction conveyed no impact on image quality. This low dose spine CT protocol allows detailed evaluation that is necessary for preoperative planning and postoperative evaluation. (orig.)

  3. CT scanning in pediatric head trauma: correlation of clinical features with CT scan diagnosis

    International Nuclear Information System (INIS)

    Arkoncel, Mary Ann P.; Posadas, Ma. Belen A.

    1997-01-01

    A retrospective review was conducted on 205 cases of pediatric head trauma for which cranial computed tomography scans were done at the Makati Medical Center, to determine which clinical features might positively predict an abnormality on CT scan. The clinical findings of loss of consciousness, GCS < 12, vomiting headache, seizures, and focal abnormalities on Neurologic Examination were significantly associated with abnormal findings on CT scan. However, a significant discrepancy does exist as to how accurately clinical findings do in fact predict normal and abnormal CT scan findings. Such a discrepancy allows us to conclude that a more liberal use of CT Scanning in cases of pediatric head trauma must be stressed to insure proper diagnosis. This study shows that when a patient presents with the aforementioned positive signs and symptoms, or with a focal neurologic deficit, or in combination, a 60-100 % positive prediction of abnormal CT Scan can be made. However, prediction of normal CT Scan is only 0-40%. (Author)

  4. Role of CT in the Diagnosis of Nonspecific Abdominal Pain: A Multicenter Analysis.

    Science.gov (United States)

    Eisenberg, Jonathan D; Reisner, Andrew T; Binder, William D; Zaheer, Atif; Gunn, Martin L; Linnau, Ken F; Miller, Chad M; Tramontano, Angela C; Herring, Maurice S; Dowling, Emily C; Halpern, Elkan F; Donelan, Karen; Gazelle, G Scott; Pandharipande, Pari V

    2017-03-01

    The objective of our study was to determine whether specific patient and physician factors-known before CT-are associated with a diagnosis of nonspecific abdominal pain (NSAP) after CT in the emergency department (ED). We analyzed data originally collected in a prospective multicenter study. In the parent study, we identified ED patients referred to CT for evaluation of abdominal pain. We surveyed their physicians before and after CT to identify changes in leading diagnoses, diagnostic confidence, and admission decisions. In the current study, we conducted a multiple regression analysis to identify whether the following were associated with a post-CT diagnosis of NSAP: patient age; patient sex; physicians' years of experience; physicians' pre-CT diagnostic confidence; and physicians' pre-CT admission decision if CT had not been available. We analyzed patients with and those without a pre-CT diagnosis of NSAP separately. For the sensitivity analysis, we excluded patients with different physicians before and after CT. In total, 544 patients were included: 10% (52/544) with a pre-CT diagnosis of NSAP and 90% (492/544) with a pre-CT diagnosis other than NSAP. The leading diagnoses changed after CT in a large proportion of patients with a pre-CT diagnosis of NSAP (38%, 20/52). In regression analysis, we found that physicians' pre-CT diagnostic confidence was inversely associated with a post-CT diagnosis of NSAP in patients with a pre-CT diagnosis other than NSAP (p = 0.0001). No other associations were significant in both primary and sensitivity analyses. With the exception of physicians' pre-CT diagnostic confidence, the factors evaluated were not associated with a post-CT diagnosis of NSAP.

  5. Diagnosis of adrenal adenoma and hyperplasia by CT and adrenal scintigraphy

    International Nuclear Information System (INIS)

    Miura, Kentaro; Itami, Jun; Nawano, Shigeru; Okada, Junichi; Ogino, Takashi; Uno, Koichi; Arimizu, Noboru

    1985-01-01

    The evaluation of X-CT and adrenal scintigraphy in diagnosis of Cushing syndrome and primary aldosteronism was studied in 18 patients. In Cushing syndrome, CT appearance of adenoma is commonly larger than that of primary aldosteronism and cleary deliniated by surrounding fat. So, in Cushing syndrome, diagnosis of adenoma on CT is much easier than that of primary aldosteronism, and absence of adenoma on CT suggests adrenal hyperplasia. In primary aldosteronism both of CT and scintigraphy must be performed. (author)

  6. CONTRAST STUDY ON CT AND BA IN DIAGNOSIS OF PATIENTS WITH ATHEROTHROMBOTIC BRAIN INFARCTION

    Institute of Scientific and Technical Information of China (English)

    Mingshun Liu; Haixiang Gao; Xiaomei Fu; Po Ma

    2007-01-01

    Objectives: To explore applied value on CT and BA in diagnosis of patients with atherothrombotic brain infarction. Methods:CT and BA were examined in 246 patients with atherothrombotic brain infarction. Results:The different change of CT and BA were showed in 246 patients with atherothrombotic brain infarction. Conclusions: There were separately different advantage and shortcoming in CT and BA in diagnosis of atherothrombotic brain infarction. The value of clinical application of BA was important in diagnosis of atherothrombotic brain infarction.

  7. The CT diagnosis and differential diagnosis of malignant tumours of the paranasal sinuses

    International Nuclear Information System (INIS)

    Graber, H.R.; Zaunbauer, W.; Haertel, M.

    1986-01-01

    The CT appearances of malignant tumours of the paranasal sinuses are illustrated on the basis of 15 patients, and the differential diagnosis discussed. Malignant soft tissue tumours in the paranasal sinuses are characterised on CT by their non-homogeneous structure; they may destroy the bony margins of the sinus and infiltrate neighbouring regions in certain preferred directions, and they may enhance following the administration of contrast. Precise definition of the malignant tumour by CT permits their exact staging, may help to determine therapy and is valuable for serial observation. It remains to be seen, however, whether the improved radiological diagnosis results in improved prognosis of malignant tumours of the paranasal sinuses. (orig.) [de

  8. CT diagnosis of rare histological variant of hepatocellular carcinoma

    International Nuclear Information System (INIS)

    Li Huaibo; Feng Zhipeng; Duan Shaoyin; Zhaugn Xiangrong

    2009-01-01

    Objective: To explore and understand the CT findings of 5 rare histological variants of hepatocellular carcinoma. Methods: CT findings of 31 cases of rare histological variants confirmed by surgery and pathology were analyzed retrospectively. Results: 13 cases were clear cell hepatocellular carcinoma. 3 cases of them showed patchy fat density in plain scans. Enhanced CT showed features of 'fast in fast out' which was similar to the common hepatocellular carcinoma. 4 cases belonged to sclerosis hepatocellular carcinoma. They appeared as heterogeneous, slowly enhancement on arterial phase images, and delay enhancement on portal venous phase and delay phase images. 9 cases belonged to mixed hepatocellular carcinoma. 5 cases of them showed inhomogeneous enhancement and 4 without enhancement during arterial phase, 3 cases showed delay enhancement and 4 without during portal venous and delay phase. 3 cases were fibrolamellar hepatocellular carcinoma. All showed obvious and fastly enhancement on arterial phase images, subsided slowly on the portal venous and delay phase images, showing features of 'fast in slow out', no enhancement was seen in the central scar. Shrinkage phenomenon on the surface of liver could be seen on the CT plain scans in sclerosis, mixed and fibrolamellar hepatocellular carcinoma. 2 cases were the type of dense hepatocellular carcinoma. The surrounding part in the 2 cases were slightly enhanced, while the most part of the center were not enhanced similar to necrosis. Conclusion: The CT findings of rate histological variant of hepatocellular carcinoma are characteristic. Analyzing the CT plain and enhancement finding is helpful to the diagnosis of these types of hepatocellular carcinoma. (authors)

  9. Diagnostic difficulties in the differentiation of neurogenic tumors of the parapharyngeal space in helical CT evaluations: A case report

    International Nuclear Information System (INIS)

    Czerniewicz-Kaminska, A.; Nowicki, J.; Jazwiec, P.; Kedzierski, B.; Janeczek, T.; Wilczynski, K.; Prudlak, E.

    2005-01-01

    Computerized tomography (CT) with contrast infusion and magnetic resonance imaging (MRI) play important roles in establishing the place of origin of neurogenic tumors. In this article we do not compare these two methods, but focus on the crucial role of CT imaging in the estimation and differential diagnosis of these tumors. We present the case of a 50-year-old man with clinical symptoms of peritonsillar abscess, which appeared to be a neurogenic tumor. The images obtained were deemed ambiguous. The possibility of a parotid gland tumor or a tumor of neurogenic origin was assumed. In this case we observed atypical clinical and radiological symptoms. The final diagnosis was based on a combination of radiological, clinical, and microbiological features of the tumor. Thanks to the cooperation of many professionals, we managed to establish the diagnosis of neuroangiofibroma, which exemplifies a tumor of the borderline, including elements of the neurogenic sheath and connective and chromaffin tissue. (author)

  10. Ligation of the internal maxillary artery for intractable epistaxis. 3D imaging of internal maxillary artery using helical CT scan

    International Nuclear Information System (INIS)

    Handa, Toru; Yazin, Koji; Hirakawa, Katsuhiro; Fukushima, Noriyuki; Takumida, Masaya; Hirata, Shitau; Iguchi, Tetsuhiko; Amano, Yoshiharu

    2001-01-01

    Sever posterior epistaxis is one of the serious clinical problems. Nasal bleeding usually occurs in the anterior septal region, where it can be seen easily and controlled with topical cautery or localized packing. When the bleeding occurs in the posterior nose, it becomes a more serious problem. Many methods have been used to control posterior epistaxis. Some of these are electrocautery, posterior nasal packing, vascular ligation and therapeutic percutaneous embolization. Between 1997 and 2000, nineteen patients were admitted to our hospital because of intractable epistaxis. There were 16 male and 3 female patients whose average age was 55 years. Ten of 19 patients were hypertensive, and none of these had undergoing treatment. Five of 19 patients received maxillary artery ligation. Clinical applications of 3D imaging of the internal maxillary artery using helical CT scan were done for 5 patients. These images were helpful for planning of ligation of the internal maxillary artery. (author)

  11. Ligation of the internal maxillary artery for intractable epistaxis. 3D imaging of internal maxillary artery using helical CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Handa, Toru [Akitsu Prefectual Hospital, Hiroshima (Japan); Yazin, Koji; Hirakawa, Katsuhiro; Fukushima, Noriyuki; Takumida, Masaya; Hirata, Shitau; Iguchi, Tetsuhiko; Amano, Yoshiharu

    2001-03-01

    Sever posterior epistaxis is one of the serious clinical problems. Nasal bleeding usually occurs in the anterior septal region, where it can be seen easily and controlled with topical cautery or localized packing. When the bleeding occurs in the posterior nose, it becomes a more serious problem. Many methods have been used to control posterior epistaxis. Some of these are electrocautery, posterior nasal packing, vascular ligation and therapeutic percutaneous embolization. Between 1997 and 2000, nineteen patients were admitted to our hospital because of intractable epistaxis. There were 16 male and 3 female patients whose average age was 55 years. Ten of 19 patients were hypertensive, and none of these had undergoing treatment. Five of 19 patients received maxillary artery ligation. Clinical applications of 3D imaging of the internal maxillary artery using helical CT scan were done for 5 patients. These images were helpful for planning of ligation of the internal maxillary artery. (author)

  12. CT diagnosis of pancreatic carcinoma and chronic pancreatitis

    International Nuclear Information System (INIS)

    Luan Baoqing; Jin Erhu; Zhang Lizhen; Jiang Haibin

    1997-01-01

    To improve the diagnostic accuracy of pancreatic carcinoma and chronic pancreatitis. The CT findings of 154 cases with pancreatic carcinoma, chronic pancreatitis and mis-diagnosed other pancreatic diseases proven clinically and pathologically were analysed. Slice thickness of 8 mm and slice interval of 8 mm were used and thin-section scan and enhancement study were performed in some cases. The main signs in degassing and differential diagnosis between pancreatic carcinoma and chronic pancreatitis included: (1) focal or diffuse enlargement and density abnormality of pancreas; (2) dilated common bile duct was suddenly obstructed, peripancreatic blood vessels were invaded and cancerous thrombus was revealed, enlargement of abdominal lymph nodes and metastasis in the liver were discovered; (3) calcium deposit in the pancreatic duct area and dilated pancreatic duct which passed through the lesion or not; (4) presence and location of pancreatic cyst and its relationship to pancreatic contour. CT is the imaging modality of choice in the diagnosis of pancreatic carcinoma and chronic pancreatitis at present. The diagnostic accuracy of CT was over 90% in this series

  13. X-ray and CT diagnosis of intraosseous ganglion

    International Nuclear Information System (INIS)

    Gong Xiangyang; Zhang Weimin; Yan Shigui

    2002-01-01

    Objective: To investigate the pathogenesis, clinical manifestations, imaging features, and differential diagnosis of intraosseous ganglion. Methods: Clinical and imaging features of 15 cases (5 men, 10 women; mean age 39.7 years) with intraosseous ganglia were retrospectively analyzed. There were 17 lesions, including 6 acetabular, 4 lunate, 3 proximal ends of tibia, 1 major tuberculum of humeral, 1 femoral head, 1 scaphoid, and 1 phalange. Results: ( 1 ) Common radiological features included a unilocular or multilocular cyst surrounded by a full and thin rim of sclerotic: bone in the subchondral epiphysis without any signs of degenerative joint disease. (2) Lesions were displayed as well-defined round radiolucent defect or multi-cystic changes with surrounding bony sclerosis or cystic and expansile change with irregular shape on CT scans. (3) CT showed an intraosseous ganglion communicating with adjacent joint in 1 patient. (4) CT values of the lesions were between 15 - 80 HU. (5) Gas in the cyst could be seen in 3 cases. Conclusion: Combined with patient's age, lesion distribution, clinical manifestations, and imaging features, it is possible to make a correct diagnosis of intraosseous ganglion

  14. CT manifestation of the carcinoma of ovary: diagnosis and differential diagnosis

    International Nuclear Information System (INIS)

    Liu Mingjuan; Guo Yan; Zhang Ling; Huang Zhaomin

    2007-01-01

    Objective: To study the CT manifestations of carcinoma of ovary and the CT findings that mimic the carcinoma of ovary. Methods: CT findings were retrospectively studied in 47 cases of pelvic masses including 42 cases of carcinoma of ovary and 5 misdiagnosed as carcinoma of ovary. Misdiagnosis was made in 8 of the 42 cases of carcinoma of ovary. Non-contrast and enhanced CT scan were performed in all cases. Results: Pelvic or abdominal-pelvic masses were demonstrated in 92.4% cases. The lesions were parenchymatous, cystic, or cystic-parenchymatous masses, in which the parenchyma and septum were remarkably enhanced after the contrast agent was given intravenously. No mass was found in 7.6% cases, in which the ascites and thickening of the omentum were noted on CT images. Ascites was shown in 57.2% cases. Calicification was manifested in 19.0% cases. Abscess or tuberculosis located in pelvis could have the similar CT findings with cystic carcinoma of ovary, while these infectious lesions presented with regular or smooth wall and septum, instead of mural nodule. Another characteristic sign of abscess or tuberculosis was air density identified within the cavity of the cysts. Chocolate cysts with recent hemorrhage or subserous leiomyoma uteri with cystic degeneration were cystic-parenchymatous mass during the non-contrast enhanced scan. No enhancement could be revealed in parenchyma of the former and slight enhancement could be identified in the parenchymatous component of the latter. Conclusion: Contrast enhanced CT scan can demonstrate the structure of the mass and the adjacent organs, and reveal the enhancement of the lesions, which plays a valuable role in diagnosis or differential diagnosis of carcinoma of ovary with atypical CT findings. (authors)

  15. CT and MRI diagnosis of posterior fossa atypical ependymoma

    International Nuclear Information System (INIS)

    Yu Bolang; Zhang Ming; Luo Lin; Wang Shijie; Zhu Liping

    2000-01-01

    Objective: To analyse the CT and MRI features of posterior fossa atypical ependymoma. Methods: Sixteen cases of posterior fossa atypical ependymoma proved by surgery and pathology had CT and (or) MRI scanning. There were 11 males and 5 females. The age ranged from 17 to 46 (mean, 31.2). Twelve cases ranged from 20 to 40 years old. the main symptoms of all cases were dizziness, unsteady walking and vomiting. Results: The locations of all cases were cerebellum (12 cases), vermis (3 cases) and cerebellopontile angle (1 cases). Fifteen cases were solid with multiple cystic changes and 1 case in the cerebellopontile angle was cystic. The tumor was usually close to the surface of cerebellum with rather extensive connection with dura mater or tentorium. Calcifications were shown in 3 cases. The tumors revealed inhomogeneous density on CT scan and inhomogeneous intensity on MRI. Mild inhomogeneous enhancement was shown in most cases, while intense irregular enhancement in the others. Conclusions: The characteristic findings of the posterior fossa atypical ependymoma ependymoma were cerebellar intraparenchymatous multiple small cystic changes within solid tumor in most cases and inhomogeneous density and intensity on CT and MRI. The differential diagnosis is meningioma, metastasis and acoustic schwannoma

  16. Findings chest radiograph and CT in mediastinitis: effcacy of CT in patients with delayed diagnosis

    International Nuclear Information System (INIS)

    Son, Eun Ju; Hong, Yong Kook; Choe, Kyu Ok

    1999-01-01

    To analyse the causes the radiologic findings in patients with mediastinitis and to evaluate the efficacy of chest CT scanning in patients with delayed diagnosis. Seventeen patients with histopathologically(n=15) or clinically diagnosed(n=2) mediastinitis were involved in this study. Eleven of the former group underwent surgery, and in four, tube drainage was performed. All underwent chest radiography and CT scanning, and in seven patients, the causes of delayed diagnosis were analysed. The most common cause of mediastinitis was esophageal rupture(n=11). Others were extension from neck abscess to the mediastinum(n=3), complications after a Benthall procedure(n=1), tuberculous lymphadenitis(n=1) and mycotic aneurysm(n=1). Patients with esophageal rupture suffered from underlying diseases such as esophageal cancer(n=2), iatrogenic esophageal rupture(n=2), Boerhaave's syndrome(n=2), and esophagitis(n=1). In patients with neck abscess (n=3), each was secondary to infected cystic hygroma, Ludwig angina, or deep neck infection, respectively. On chest CT, patients with esophageal rupture(n=11) had an abscess in the posterior mediastinum ; nine abscesses extended to the cervical area along the retropharyngeal space, and the patient with Ludwig angina had an abscess involving all compartments of the mediastinum. Among the total of 17 patients, diagnostic delays were found in seven, while five had spontaneous esophageal ruptures and two suffered complications after a Benthall procedure and Tbc lymphadenitis, respectively. The causes of diagnostic delay varied. Among seven patients, pnevmonia was initially diagnosed in two, who were treated ; one had multiorgan failure, and one was suffering from pericardial effusion and lung abscess. In three other patients, chest radiographs initially showed non-specific findings, leading to delayed CT examination. The most common cause of mediastinitis was esophageal rupture, and in these patients, chest radiographs and clinical symptoms

  17. Multiphasic helical CT of hepatocellular carcinoma. Evaluation after chemoembolization; Tomografia Computerizzata spirale multifasica dell'epatocarcinoma. Valutazione dopo chemioembolizzazione

    Energy Technology Data Exchange (ETDEWEB)

    Catalano, O.; Esposito, M.; Sandomenico, F.; Siani, A. [Ospedale S. Maria delle Grazie, Pozzuoli, NA (Italy). Servizio di Radiologia; Nunziata, A. [Ospedale S. Maria delle Grazie, Naples (Italy). Area di Diagnostica per Immagini

    2000-06-01

    The main purpose of this work is to report the personal experience with addition of contrast-enhanced multiphase helical CT to unenhanced CT (Lipiodol CT) in the evaluation of patients with hepatocellular carcinoma treated with chemoembolization and to analyze the present role of oily agent CT. It has been retrospectively reviewed the examinations of 42 consecutive patients submitted to global chemoembolization over a 2-year period. CT was performed 18-30 days after the treatment. The Lipiodol CT study was carried out with volume acquisitions. It has been considered as nodules all well-defined areas with dense oily agent uptake; uptake itself was classified as: 0=absent, I=lower than 10% of the tumor volume; II=lower than 50%, III=50%, IV=homogeneous. Contrast-enhanced helical CT was performed with the 2-phase technique in 28 patients and with the 3-phase technique in 14; it has been considered as nodules all well-defined and relatively homogeneous areas with hyper attenuation in the arterial phase and hypo-iso attenuation in the portal and/or delayed phase, or with hypo-iso attenuation in the arterial phase and in the portal and/or delayed phase. Lipiodol CT permitted to recognize 65 nodules (1-5/patient, mean 1.5), namely 15 grade I, 21 grade II, 20 grade III and 9 grade IV. Multiphase CT identified 6 additional nodules in 5 patients, 5 hyper vascular and 1 hypo vascular, and better assessed the correct morphology and volume of grade I nodules. Only 4 of 6 nodules missed on Lipiodol CT showed oily agent uptake after a new chemo embolization session. Moreover after retreatment, carried out in 6 of 9 patients with grade I uptake (11 nodules in all), it has been found persistence of the grade I pattern in 5 nodules, grade II in 5, and grade III in 1. Lipiodol CT may miss liver nodules and underestimate the volume of nodules with poor uptake. Though Lipiodol CT should still be considered slightly more sensitive than multiphase CT, in the general opinion this

  18. DIPNECH: when to suggest this diagnosis on CT

    International Nuclear Information System (INIS)

    Chassagnon, G.; Favelle, O.; Marchand-Adam, S.; De Muret, A.; Revel, M.P.

    2015-01-01

    Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is an under-recognized disease characterized by proliferation of neuroendocrine cells in the bronchial wall. It is considered a pre-invasive lesion for lung carcinoid tumours and is found in 5.4% of patients undergoing surgical resection for lung carcinoid tumours. Other manifestations of DIPNECH include bronchial obstruction and formation of tumorlets. DIPNECH preferentially affects middle-aged women. Patients are either asymptomatic or present with long-standing dyspnoea due to obstructive syndrome that can be mistaken for asthma. At CT, mosaic attenuation with multiple small nodules is very suggestive of DIPNECH. The aim of this review is to describe DIPNECH-related CT features and correlate them with histology, in order to help radiologists suggest this diagnosis and distinguish DIPNECH from other causes of mosaic perfusion

  19. Diagnosis of pelvic wall tumor on multislice CT

    International Nuclear Information System (INIS)

    Zhang Keyun; Deng Lequn; Lei Hongwei

    2011-01-01

    Objective: To evaluate the value of multi-slice CT (MSCT) in diagnosing pelvic wall tumors. Methods: MSCT of 21 cases of pelvic wall tumors including metastasis (10), neurogenic tumor (5), chondrosarcoma (2), chordoma (1), aneurysmal bone cyst (1), giant cell tumor (1), and osteochondroma (1) was retrospectively analyzed. Results: CT appearances of pelvic wall tumors include bony destruction and soft tissue masses. Common features were bone destruction in metastasis, expansion of the neuroforamen in neurogenic tumor, pleomorphic calcification in chondrosarcoma, lower sacral vertebral location of chordoma, iliac crest bone destruction in giant cell tumor, cauliflower-like nodules in osteochondroma. Conclusion: MSCT with three-dimensional volume rendering demonstrates well the tumor shape, size, extent, internal structure and relationship with the surrounding organs to aid diagnosis of pelvic wall tumors. (authors)

  20. CT diagnosis and clinical of leukoaraosis (with 145 cases report)

    International Nuclear Information System (INIS)

    Yang Minzheng

    2005-01-01

    Objective: To investigate pathogenesis of leukoaraosis, the correlation between CT presentation and clinical symptom and to provide useful evidence for clinical diagnosis and treatment. Methods: CT presentation and clinical symptoms in the Leukoaraosis of 145 cases were retrospectively analyzed. Results: Leukoaraosis manifested symmetrical hypo-dense lesion adjacent to frontal horn and/or occipital horn of bilateral ventricles; symmetrical hypo-dense peri-ventricle patches; or diffuse hypo-dense white matter. Lacunar infarction or hemorrhage of basal ganglion and/or thalamus may also be revealed. Conclusion: Leukoaraosis often involves the white matter adjacent to the frontal horn and occipital horn of bilateral ventricles. And entire peri-ventricle white matter may be affected in severe cases. The pathology of the disease is related to demyelination of brain white matter, resulting in the characteristic vascularity in white matter, which may alter under hypertension. (authors)

  1. SU-E-I-93: Improved Imaging Quality for Multislice Helical CT Via Sparsity Regularized Iterative Image Reconstruction Method Based On Tensor Framelet

    International Nuclear Information System (INIS)

    Nam, H; Guo, M; Lee, K; Li, R; Xing, L; Gao, H

    2014-01-01

    Purpose: Inspired by compressive sensing, sparsity regularized iterative reconstruction method has been extensively studied. However, its utility pertinent to multislice helical 4D CT for radiotherapy with respect to imaging quality, dose, and time has not been thoroughly addressed. As the beginning of such an investigation, this work carries out the initial comparison of reconstructed imaging quality between sparsity regularized iterative method and analytic method through static phantom studies using a state-of-art 128-channel multi-slice Siemens helical CT scanner. Methods: In our iterative method, tensor framelet (TF) is chosen as the regularization method for its superior performance from total variation regularization in terms of reduced piecewise-constant artifacts and improved imaging quality that has been demonstrated in our prior work. On the other hand, X-ray transforms and its adjoints are computed on-the-fly through GPU implementation using our previous developed fast parallel algorithms with O(1) complexity per computing thread. For comparison, both FDK (approximate analytic method) and Katsevich algorithm (exact analytic method) are used for multislice helical CT image reconstruction. Results: The phantom experimental data with different imaging doses were acquired using a state-of-art 128-channel multi-slice Siemens helical CT scanner. The reconstructed image quality was compared between TF-based iterative method, FDK and Katsevich algorithm with the quantitative analysis for characterizing signal-to-noise ratio, image contrast, and spatial resolution of high-contrast and low-contrast objects. Conclusion: The experimental results suggest that our tensor framelet regularized iterative reconstruction algorithm improves the helical CT imaging quality from FDK and Katsevich algorithm for static experimental phantom studies that have been performed

  2. CT differential diagnosis between angiomyolipoma and carcinoma of kidney

    International Nuclear Information System (INIS)

    Tang Guangjian; Xu Yan

    2004-01-01

    Objective: To investigate the formation of the cup sign and split sign in renal neoplasms and to evaluate the significance of these signs in CT differential diagnosis between angiomyolipoma (AML) and carcinoma of the kidney. Methods: Thirty cases of AMLs of kidney less than 5 cm in diameter confirmed pathologically or by the fat component shown in CT, and 26 cases of primary renal carcinomas less than 4 cm in diameter confirmed by operation and pathology were included in this study. The positive rates of cup sign and split sign of AML group and renal carcinoma group were calculated respectively and studied with blind method and pathologic comparison. Results: Of the 30 AMLs, cup sign was positive in 25 cases (83.3%) and split sign in 22 (73.3%). Of the 26 small renal carcinomas, cup sign was positive in 6 cases (23.1%) and split sign in 5 (19.2%). 7 AMLs without fat component or with too little fat to be seen with CT showed positive findings of cup sign in 6 (85.7%) and split sign in 5 (71.4%), respectively. The statistical results showed that the differences between the results of the writer and blind method, as well as between the imaging observation and pathologic findings were not significant (χ 2 =2.333, P>0.1; χ 2 =0.177, P>0.5). Conclusion: To some extent, the cup sign and split sign on CT reflect the biologic character of AMLs, and the signs are helpful in making the specific diagnosis of AML combined with other imaging manifestations. (authors)

  3. Diagnosis of malignant pleural effusion and lung cancer with CT

    International Nuclear Information System (INIS)

    Jakimovska, S.; Jakimovska, M.; Jovanovska, S.; Ilieva, S.

    2012-01-01

    Full text: Introduction: A pleural effusion is defined as an abnormal amount of fluid in the space between the layers of tissue (the pleura) that line the lungs. If cancer cells are present in this fluid (pleural cavity) it is called a malignant cancerous pleural effusion. Many benign and malignant disease can cause pleural effusion.The new onset of pleural effusion may herald the presence of a previously undiagnosed malignancy, or more typically, complicate the course of a known lung tumor. Malignant pleural effusions can lead lead to an initial diagnosis of lung cancer in patients.and it was the first symptom of lung cancer. Pleural deposits of tumor cause pleuritic pain. Purpose of this presentation is to show the role of CT in diagnosis of malignant pleural effusion and lung cancer. Material and methods: CT examinations of chest were made to 138 patients for 1 year (1/6/2011- 1/6/2012) with Siemens Somatom Emotion 16 CT Scanner. Patients were at age of 30 -81 years, 93 of them are male and 45 are female. Results: 56 (40.5%) of the patients had pleural effusion. From this group 21 37.5% had malignant pleural effusion and lung cancer. 17 (81%) of them are male, and 4 (19%) are female. 9 (43%) diagnosed lung cancer for first time. Conclusion: Pleural effusion more commonly occur in patient with advanced-stage tumor who frequently have metastases to other organs and long-term survival is uncommon in this group. CT diagnosed malignant pleural effusion and lung cancer and help to choice treatment for these patients

  4. CT diagnosis and differential diagnosis of the masses in lateral district of neck

    International Nuclear Information System (INIS)

    Cai Wenchong; Wei Zengcai; Li Huajie

    2006-01-01

    Objective: To analyze the CT findings and the corresponding anatomic basis of the masses arising in the lateral district of neck, and improve the diagnosis. Methods: CT findings in 52 patients with tumours in lateral district of neck, pathologically proved, were retrospectively studied on the size of the masses, morphology, density, margin, contrast enhanced characteristics, location and relationship with adjacent vessels and spaces. Results: Among the 52 cases, masses were located in the prestyloid space in 8 cases, in the parotid in 8, within the masticator space in 2, and in the carotid space in 31. In most of the cases, CT revealed the pathologic nature of the masses and adjacent anatomic structure. According to the displacement of the adjacent spaces muscles and vessels caused by the masses, the origin of the masses could be predicted. The origin of the masses was spatially related to the internal carotid artery and the jugular vein. Conclusion: CT is an effective modality for the positional diagnosis of the masses arising lateral district of neck. Considering the anatomical position and contrast enhanced characteristics and the involvement of the adjacent structure, the qualitative and differential diagnosis can be improved. (authors)

  5. Evaluation of the retrospective ECG-gated helical scan using half-second multi-slice CT. Motion phantom study for volumetry

    International Nuclear Information System (INIS)

    Yamamoto, Shuji; Matsumoto, Takashi; Nakanishi, Shohzoh; Hamada, Seiki; Takahei, Kazunari; Naito, Hiroaki; Ogata, Yuji

    2002-01-01

    ECG synchronized technique on multi-slice CT provide the thinner (less 2 mm slice thickness) and faster (0.5 sec/rotation) scan than that of the single detector CT and can acquire the coverage of the entire heart volume within one breath-hold. However, temporal resolution of multi-slice CT is insufficient on practical range of heart rate. The purpose of this study was to evaluate the accuracy of volumetry on cardiac function measurement in retrospective ECG-gated helical scan. We discussed the influence of the degradation of image quality and limitation of the heart rate in cardiac function measurement (volumetry) using motion phantom. (author)

  6. Electron-beam CT diagnosis of congenital cardiovascular diverticula

    International Nuclear Information System (INIS)

    Yang Youyou; Zheng Lili; Li Xiangmin; Zhou Xuhui; Peng Qian; Meng Quanfei; Dai Ruping

    2008-01-01

    Objective: To investigate the clinical application of electron-beam CT (EBCT) in the diagnosis of congenital cardiovascular diverticula. Methods: Retrospective analysis of 9 patients with congenital cardiovascular diverticula confirmed by operation and pathology was done. Of them, enhanced continuous volume scan was performed on 8 patients and enhanced single slice scan was performed on one patient with an Imatron C-150 scanner. Results: The group of 9 patients included one patient with diverticulum of the left ventricle, 3 patients with diverticulum of the atria and 5 patients with diverticulum of the aorta. EBCT scan and three dimensional reconstruction could demonstrate not only the origin, size, shape, location and adjacent structure of diverticula, but also other important complicated abnormalities such as ventriculoarterial connection disorder, cardiac septal defect, aortic coarctation and even dissection. Conclusion: EBCT is an ideal noninvasive technique in the diagnosis of congenital cardiovascular diverticula. (authors)

  7. Computer-aided diagnosis of colonic polyp by CT colonography

    International Nuclear Information System (INIS)

    Yoshida, Hiroyuki

    2007-01-01

    The outcome of National CT Colonography Trial, by American College of Radiology Imaging Network, 2006 (www.acrin.org/6664 protocol), possibly leads to the introduction of colorectal cancer screening in the US because CT colonography (CTCG) has been approved in the health insurance system. This paper describes the outline of computer-aided diagnosis (CAD) of colonic polyp by CTCG, its polyp detectability and future aspects. CTCG essentially derives from the virtual, abdominal 3D CT images and gives as many as about 500 images/patient, in the reading of which CAD support the expert. CAD technology in CTCG is said to have been essentially established in the first half of 2000s, which involves the cleansing of fecal tagging effect, extraction of the colonal wall from the image, detection of suspicious polyp, reduction of false-positive findings and displaying of the detected polyp. The detectability is thought to be at comparable level to expert's. The last displaying is done on the user-interface like Colon CAD Workstation. More efficient expert's reading with CAD, imaging without previous gut cleansing, detection of the flat lesion and further reduction of false-positive are the forthcoming tasks in clinical practice. Significance of CTCG is becoming in realization and its usage with CAD is thought to be more popular in Japan. (R.T.)

  8. Topographic diagnosis of parathyroid tumor by CT scan

    International Nuclear Information System (INIS)

    Fukunaga, Masao; Harioka, Toshio; Morita, Rikuji

    1981-01-01

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

  9. Radiation dose and cancer risk estimates in helical CT for pulmonary tuberculosis infections

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    Adeleye Bamise

    2017-12-01

    Full Text Available The preference for computed tomography (CT for the clinical assessment of pulmonary tuberculosis (PTB infections has increased the concern about the potential risk of cancer in exposed patients. In this study, we investigated the correlation between cancer risk and radiation doses from different CT scanners, assuming an equivalent scan protocol. Radiation doses from three 16-slice units were estimated using the CT-Expo dosimetry software version 2.4 and standard CT scan protocol for patients with suspected PTB infections. The lifetime risk of cancer for each scanner was determined using the methodology outlined in the BEIR VII report. Organ doses were significantly different (P < 0.05 between the scanners. The calculated effective dose for scanner H2 is 34% and 37% higher than scanners H3 and H1 respectively. A high and statistically significant correlation was observed between estimated lifetime cancer risk for both male (r2 = 0.943, P < 0.05 and female patients (r2 = 0.989, P < 0.05. The risk variation between the scanners was slightly higher than 2% for all ages but was much smaller for specific ages for male and female patients (0.2% and 0.7%, respectively. These variations provide an indication that the use of a scanner optimizing protocol is imperative.

  10. Intraductal papillary mucinous neoplasms of the pancreas: Correlation of helical CT features with pathologic findings

    International Nuclear Information System (INIS)

    Liu Yu; Lin Xiaozhu; Upadhyaya, Manavendra; Song Qi; Chen Kemin

    2010-01-01

    Objective: To evaluate the CT features of intraductal papillary mucinous neoplasms of the pancreas (IPMNs), and to compare with pathological findings in order to identify CT features that can be helpful in differentiating benign IPMNs from malignant IPMNs. Materials and methods: The CT findings in 25 patients were reviewed for tumor location, tumor type, dilatation of the main pancreatic duct (MPD), MPD involvement, mural node or solid attenuating component, tumor size in branch duct or mixed duct type, dilatation of common bile duct (CBD) and invasion of surrounding structures. The data was subjected to Chi-Square Tests or Fisher's Exact Test using SPSS13.0 software with p value < 0.05 indicating significant statistical difference. Results: Presence of mural node or solid enhancing component, size of mural node or solid enhancing component ≥7 mm, dilatation of CBD was more common in malignant IPMNs (p < 0.05). None of tumor location, tumor type, dilatation of MPD, MPD involvement, tumor size, and invasion of surrounding structures was statistically significant in differentiating benign from malignant IPMNs. Conclusions: CT features suggestive of malignant or invasive IPMNs include presence of mural node or solid enhancing component, size of mural node or solid enhancing component ≥7 mm, and dilatation of CBD.

  11. Radiation dose and cancer risk estimates in helical CT for pulmonary tuberculosis infections

    Science.gov (United States)

    Adeleye, Bamise; Chetty, Naven

    2017-12-01

    The preference for computed tomography (CT) for the clinical assessment of pulmonary tuberculosis (PTB) infections has increased the concern about the potential risk of cancer in exposed patients. In this study, we investigated the correlation between cancer risk and radiation doses from different CT scanners, assuming an equivalent scan protocol. Radiation doses from three 16-slice units were estimated using the CT-Expo dosimetry software version 2.4 and standard CT scan protocol for patients with suspected PTB infections. The lifetime risk of cancer for each scanner was determined using the methodology outlined in the BEIR VII report. Organ doses were significantly different (P < 0.05) between the scanners. The calculated effective dose for scanner H2 is 34% and 37% higher than scanners H3 and H1 respectively. A high and statistically significant correlation was observed between estimated lifetime cancer risk for both male (r2 = 0.943, P < 0.05) and female patients (r2 = 0.989, P < 0.05). The risk variation between the scanners was slightly higher than 2% for all ages but was much smaller for specific ages for male and female patients (0.2% and 0.7%, respectively). These variations provide an indication that the use of a scanner optimizing protocol is imperative.

  12. Multislice CT for preoperative diagnosis of pancreatic cancer

    International Nuclear Information System (INIS)

    Horiguchi, Akihiko; Ishihara, Shin; Ito, Masahiro

    2007-01-01

    We investigated the ability of multislice (MS) CT to visualize and diagnose the progression of pancreatic cancer. With regard to local progression, good diagnosis was possible for detecting the invasion of the intrapancreatic bile duct, duodenum, portal vein, arteries and other organs, and liver metastasis. Sensitivity was high but specificity was not good for detecting the invasion of the anterior and posterior pancreatic tissue. This is thought to be because of the positive diagnosis with pancreatitis that accompanies cancer. Pancreatic plexus invasion was also thought to be a cause of the lipid elevation of the nerve plexus and decreased sensitivity accompanying pancreatitis. Identification of cancer invasion and tumor periphery changes based on concomitant pancreatitis also depends on the amount of fibrous stroma, but this will require further investigation. Factors other than the size of lymph node metastases also need to be investigated. MS-CT can provide detailed volume data in a short time and making it an essential test in diagnosing the stage of pancreatic cancer. (author)

  13. Suspected ureteral colic: plain film and sonography vs unenhanced helical CT. A prospective study in 66 patients

    Energy Technology Data Exchange (ETDEWEB)

    Ripolles, Tomas; Agramunt, Marcos; Errando, Jose; Martinez, Maria Jesus [Department of Radiology, Hospital Universitario Dr. Peset, 90 Gaspar Aguilar Avenue, 46017, Valencia (Spain); Coronel, Belen [Department of Urology, Hospital Universitario Dr. Peset, 90 Gaspar Aguilar Avenue, 46017, Valencia (Spain); Morales, Maria [Research Unit, Hospital Universitario Dr. Peset, 90 Gaspar Aguilar Avenue, 46017, Valencia (Spain)

    2004-01-01

    The aim of this study was to compare the sensitivity and specificity of plain abdominal films plus ultrasound, vs nonenhanced CT for the diagnosis of ureteral colic in patients with acute flank pain. During a 4-month period, 66 patients (mean age 48 years) with acute flank pain were prospectively studied by means of plain abdominal film, US, and unenhanced CT. The presence of lithiasis and of obstructive uropathy signs were determined. The plain film was only used as a guide for the US exam. Clinical follow-up of all patients was obtained. Ureteral lithiasis was confirmed in 56 patients. The CT had a greater sensitivity (93 vs 79%) and negative predictive value (71 vs 46%) for the detection of lithiasis. The combination of lithiasis plus obstructive signs showed a sensitivity and a specificity of 100% for CT and of 100 and 90%, respectively, for US. The 11 lithiasis not detected by US were passed spontaneously (10 were <5 mm). Both techniques showed similar extraurinary pathology. Computed tomography is the most accurate technique for the detection of ureteral lithiasis; however, the combination of plain film and US is an alternative to nonenhanced CT with a lower sensitivity and radiation dose that has a good practical value. (orig.)

  14. Multidetector CT (MD-CT) in the diagnosis of uncertain open globe injuries

    Energy Technology Data Exchange (ETDEWEB)

    Hoffstetter, P.; Schreyer, A.G.; Jung, E.M.; Heiss, P.; Zorger, N. [Inst. fuer Roentgendiagnostik, Universitaetsklinikum Regensburg (Germany); Schreyer, C.I.; Framme, C. [Klink und Poliklinik fuer Augenheilkunde, Universitaetsklinikum Regensburg (Germany)

    2010-02-15

    Purpose: To evaluate the significance of multislice CT for the diagnosis of uncertain penetrating globe injuries. Materials and Methods: Based on a retrospective chart review between 2002 and 2007, we identified 59 patients presenting with severe ocular trauma with uncertain rupture of the globe due to massive subconjunctival and/or anterior chamber hemorrhage. The IOP (intraocular pressure) was within normal range in all patients. High resolution multidetector CT (MD-CT) scans (16 slice scans) with axial and coronar reconstructions were performed in all patients. The affected eye was examined for signs of penetrating injury such as abnormal eye shape, scleral irregularities, lens dislocation or intravitreal hemorrhages. Four experienced radiologists read the CT scans independently. Beside the diagnosis, the relevant morphological criteria and the optimal plane orientation (axial or coronar) were specified. The sensitivity, specificity, and negative and positive predictive value were calculated. Additionally the interobserver variability was determined by applying the Cohen's kappa test. Surgical sclera inspections were performed in all cases as a standard of reference. The evaluations of the CT examination were compared with the surgery reports. Results: 59 patients were evaluated (42 men, 17 women). The mean age was 29 years (range 7-91). In 17 patients a rupture of the globe was diagnosed during surgery. 12 of these 17 penetrating injuries (70.6%) were classified correctly by MDCT, 5 of the 17 (29.4%) were not detectable. 42 patients did not have an open globe injury. 41 of these patients were diagnosed correctly negative by MDCT, and one patient was classified false positive. This results in a sensitivity of 70% with a specificity of 98%. There was high inter-rater agreement with kappa values between 0.89-0.96. Most discrepancies were caused by wrong negative findings. The most frequent morphologic criteria for open globe injury were the deformation (n

  15. Utility of CT Findings in the Diagnosis of Cecal Volvulus.

    Science.gov (United States)

    Dane, Bari; Hindman, Nicole; Johnson, Evan; Rosenkrantz, Andrew B

    2017-10-01

    The objective of our study was to assess the utility of CT features in the diagnosis of cecal volvulus. Forty-three patients undergoing CT for cecal volvulus and with surgical or clinical follow-up were included. Two radiologists (11 years and 1 year of experience) evaluated CT examinations for the following: whirl sign, abnormal cecal position, "bird beak" sign, severe cecal distention, mesenteric engorgement, a newly described "central appendix" sign (defined as abnormal appendix position near midline), and overall impression for cecal volvulus. Univariable and multivariable assessments were performed. Patients with CT examinations in which the appendix was not visible were excluded from calculations involving the central appendix sign. Fifty-one percent (n = 22) of patients had cecal volvulus. All CT findings were significantly more common in patients with cecal volvulus (p volvulus versus in 37.5 and 31.1% of patients without volvulus. The whirl sign exhibited a sensitivity for cecal volvulus of 90.9% for reader 1 and 95.5% for reader 2, and a specificity of 61.9% for both readers. Abnormal cecal position exhibited a sensitivity of 90.0% for reader 1 and 100.0% for reader 2 and a specificity of 66.7% and 38.1%. The bird beak sign exhibited a sensitivity of 86.4% for reader 1 and 100.0% for reader 2 and a specificity of 85.7% and 71.4%. Severe cecal distention exhibited a sensitivity of 100.0% for both readers and a specificity of 81.0% and 61.9%. Mesenteric engorgement exhibited a sensitivity of 40.9% for reader 1 and 100.0% for reader 2 and a specificity of 76.2% and 71.4%. The central appendix sign exhibited a sensitivity of 92.9% for reader 1 and 92.3% for reader 2 and a specificity of 62.5% and 68.8%. Overall impression exhibited a sensitivity of 100.0% for both readers and a specificity of 76.2% and 57.1%. At multivariable analysis, the AUC for cecal volvulus ranged from 0.787 to 0.931, and the whirl sign was an independent predictor of volvulus for both

  16. Comparison of SPECT/CT, MRI and CT in diagnosis of skull base bone invasion in nasopharyngeal carcinoma.

    Science.gov (United States)

    Zhang, Shu-xu; Han, Peng-hui; Zhang, Guo-qian; Wang, Rui-hao; Ge, Yong-bin; Ren, Zhi-gang; Li, Jian-sheng; Fu, Wen-hai

    2014-01-01

    Early detection of skull base invasion in nasopharyngeal carcinoma (NPC) is crucial for correct staging, assessing treatment response and contouring the tumor target in radiotherapy planning, as well as improving the patient's prognosis. To compare the diagnostic efficacy of single photon emission computed tomography/computed tomography (SPECT/CT) imaging, magnetic resonance imaging (MRI) and computed tomography (CT) for the detection of skull base invasion in NPC. Sixty untreated patients with histologically proven NPC underwent SPECT/CT imaging, contrast-enhanced MRI and CT. Of the 60 patients, 30 had skull base invasion confirmed by the final results of contrast-enhanced MRI, CT and six-month follow-up imaging (MRI and CT). The diagnostic efficacy of the three imaging modalities in detecting skull base invasion was evaluated. The rates of positive findings of skull base invasion for SPECT/CT, MRI and CT were 53.3%, 48.3% and 33.3%, respectively. The sensitivity, specificity and accuracy were 93.3%, 86.7% and 90.0% for SPECT/CT fusion imaging, 96.7%, 100.0% and 98.3% for contrast-enhanced MRI, and 66.7%, 100.0% and 83.3% for contrast-enhanced CT. MRI showed the best performance for the diagnosis of skull base invasion in nasopharyngeal carcinoma, followed closely by SPECT/CT. SPECT/CT had poorer specificity than that of both MRI and CT, while CT had the lowest sensitivity.

  17. Multi-detector row helical CT of the liver. Quantitative assessment of iodine concentration of intravenous contrast material on multiphasic CT. A prospective randomized study

    International Nuclear Information System (INIS)

    Tsurusaki, Masakatsu; Sugimoto, Koji; Fujii, Masahiko; Sugimura, Kazuro

    2004-01-01

    The purpose of this study was to assess the quantitative effects of contrast material concentration on hepatic parenchymal and vascular enhancement in multiphasic computed tomography (CT), using multi-detector row helical CT. We designed a prospective randomized study to test two different concentrations of contrast material on five phasic scans of the liver. One hundred patients were randomly assigned to two groups: an iodine concentration of 300 mg/mL in group A and 370 mg/mL in group B. All patients received a fixed volume of 100 mL at a 4 mL/sec injection rate. Enhancement values for the hepatic parenchyma and aorta at three levels (upper, middle, and lower level of the liver), and values for portal and hepatic veins were statistically compared between the two groups. Hepatic parenchymal enhancement values at all levels of the liver in portal phase (PP) and equilibrium phase (EP) were significantly higher in group B than in group A (p<0.01). Aortic enhancement values at two levels of the liver (middle and lower) in early hepatic arterial phase (EAP) were significantly higher in group B than in group A (p<0.05), however, there was no significant difference between groups A and B in aortic enhancement during the delayed hepatic arterial phase (DAP). Portal and hepatic venous enhancement values in PP and EP were significantly higher in group B than in group A (p<0.01). On multiphasic dynamic CT, the use of a higher iodine concentration of contrast material results in higher hepatic parenchymal enhancement and aortic enhancement, as well as higher portal and hepatic venous enhancement. (author)

  18. Unenhanced helical CT in the evaluation of the urinary tract in children and young adults following urinary tract reconstruction: comparison with sonography

    Energy Technology Data Exchange (ETDEWEB)

    Myers, M.T.; Elder, J.S.; Sivit, C.J.; Applegate, K.E. [Dept. of Radiology, Rainbow Babies and Children' s Hospital, Cleveland, OH (United States)

    2001-03-01

    Purpose. To compare the accuracy of unenhanced, helical CT with sonography for the detection of complications of urinary tract reconstruction. Materials and methods. Forty-six kidneys in 24 patients were examined with CT and sonography. All scans were assessed for ease of renal visualization, presence of renal, ureteral, and bladder calculi, renal scars, hydronephrosis, and abdominal wall hernia. The results of both imaging modalities were independently reported. Results. CT provided excellent visualization of all 46 kidneys, while sonography provided poor visualization of 8 kidneys (17 %) (P < 0.001). CT detected calculi in 10 kidneys, 1 ureter, and 7 bladders. Sonography detected calculi in only 2 kidneys, and 2 bladders. Overall, CT detected significantly more calculi than US (18 vs 4, P = 0.01). CT detected scarring in 15 kidneys, while sonography detected scarring in 10. Hydronephrosis was detected in 6 kidneys by CT and in 8 kidneys by sonography. Three abdominal wall hernias were seen at CT that were not seen at sonography. Conclusion. CT is superior to sonography for the detection of urinary tract calculi and renal scarring. CT will demonstrate abdominal wall hernias that are unsuspected. (orig.)

  19. Dual-phase helical CT using bolus triggering technique: optimization of transition time

    International Nuclear Information System (INIS)

    Choi, Young Ho; Kim, Tae Kyoung; Park, Byung Kwan; Koh, Young Hwan; Han, Joon Koo; Choi, Byung Ihn

    1999-01-01

    To optimize the transition time between the triggering point in monitoring scanning and the initiation of diagnostic hepatic arterial phase (HAP) scanning in hepatic spiral CT, using a bolus triggering technique. One hundred consecutive patients with focal hepatic lesion were included in this study. Patients were randomized into two groups. Transition times of 7 and 11 seconds were used in group 1 and 2, respectively. In all patients, bolus triggered HAP spiral CT was obtained using a semi-automatic bolus tracking program after the injection of 120mL of non-ionic contrast media at a rate of 3mL/sec. When aortic enhancement reached 90 HU, diagnostic HAP scanning began after a given transition time. From images of group 1 and group 2, the degree of parenchymal enhancement of the liver and tumor-to-liver attenuation difference were measured. Also, for qualitative analysis, conspicuity of the hepatic artery and hypervascular tumor was scored and analyzed. Hepatic parenchymal enhancement on HAP was 12.07 + /-6.44 HU in group 1 and 16.03 + /-5.80 HU in group 2 (p .05). In the evaluation of conspicuity of hepatic artery, there was no statistically significant difference between the two groups (p > .05). The conspicuity of hypervascular tumors in group 2 was higher than in group 1 (p < .05). HAP spiral CT using a bolus triggering technique with a transition time of 11 seconds provides better HAP images than when the transition time is 7 seconds

  20. Pericardial sinuses and recesses effusion of 16-slice helical CT imaging and anatomic correlation

    International Nuclear Information System (INIS)

    Lu Chunyan; Yang Zhigang; Zhou Xiangping; Yu Jianqun; Zhu Jie; Yang Kaiqing

    2007-01-01

    Objective: To evaluate the CT features and implications of the pericardial sinuses and recesses effusion by combining the sectional cadavers and 16 multi-slice CT (MSCT) reformation. Methods: The anatomy and communication of the pericardial sinuses and recesses on the axial, coronal and saggital sectional cadavers (respectively 1 case), and the morphologic features on MSCT reformatted images in 104 patients were observed. The detection rate of effusion was analyzed. Results: The sectional cadavers and CT images showed that the pericardial sinuses and recesses were formed by the reflections of the pericardium on the root of the great vessels. The detection rate of the sinuses and recesses was lower in small effusion than in moderate and large effusion (P<0.05). The superior aortic recess was the most common recess for pericardial effusion. Conclusion: The MSCT reformatted images can show the morphologic features of pericardial sinuses and recesses effusion and communications with the pericardial cavity, help differentiate pericardial effusion from other mediastinal or pericardial lesions. (authors)

  1. Findings chest radiograph and CT in mediastinitis: effcacy of CT in patients with delayed diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Son, Eun Ju; Hong, Yong Kook; Choe, Kyu Ok [Yonsei Univ. College of Medicine, Seoul (Korea, Republic of)

    1999-01-01

    To analyse the causes the radiologic findings in patients with mediastinitis and to evaluate the efficacy of chest CT scanning in patients with delayed diagnosis. Seventeen patients with histopathologically(n=15) or clinically diagnosed(n=2) mediastinitis were involved in this study. Eleven of the former group underwent surgery, and in four, tube drainage was performed. All underwent chest radiography and CT scanning, and in seven patients, the causes of delayed diagnosis were analysed. The most common cause of mediastinitis was esophageal rupture(n=11). Others were extension from neck abscess to the mediastinum(n=3), complications after a Benthall procedure(n=1), tuberculous lymphadenitis(n=1) and mycotic aneurysm(n=1). Patients with esophageal rupture suffered from underlying diseases such as esophageal cancer(n=2), iatrogenic esophageal rupture(n=2), Boerhaave's syndrome(n=2), and esophagitis(n=1). In patients with neck abscess (n=3), each was secondary to infected cystic hygroma, Ludwig angina, or deep neck infection, respectively. On chest CT, patients with esophageal rupture(n=11) had an abscess in the posterior mediastinum ; nine abscesses extended to the cervical area along the retropharyngeal space, and the patient with Ludwig angina had an abscess involving all compartments of the mediastinum. Among the total of 17 patients, diagnostic delays were found in seven, while five had spontaneous esophageal ruptures and two suffered complications after a Benthall procedure and Tbc lymphadenitis, respectively. The causes of diagnostic delay varied. Among seven patients, pnevmonia was initially diagnosed in two, who were treated ; one had multiorgan failure, and one was suffering from pericardial effusion and lung abscess. In three other patients, chest radiographs initially showed non-specific findings, leading to delayed CT examination. The most common cause of mediastinitis was esophageal rupture, and in these patients, chest radiographs and clinical

  2. Comparison of helical, maximum intensity projection (MIP), and averaged intensity (AI) 4D CT imaging for stereotactic body radiation therapy (SBRT) planning in lung cancer

    International Nuclear Information System (INIS)

    Bradley, Jeffrey D.; Nofal, Ahmed N.; El Naqa, Issam M.; Lu, Wei; Liu, Jubei; Hubenschmidt, James; Low, Daniel A.; Drzymala, Robert E.; Khullar, Divya

    2006-01-01

    Background and Purpose: To compare helical, MIP and AI 4D CT imaging, for the purpose of determining the best CT-based volume definition method for encompassing the mobile gross tumor volume (mGTV) within the planning target volume (PTV) for stereotactic body radiation therapy (SBRT) in stage I lung cancer. Materials and methods: Twenty patients with medically inoperable peripheral stage I lung cancer were planned for SBRT. Free-breathing helical and 4D image datasets were obtained for each patient. Two composite images, the MIP and AI, were automatically generated from the 4D image datasets. The mGTV contours were delineated for the MIP, AI and helical image datasets for each patient. The volume for each was calculated and compared using analysis of variance and the Wilcoxon rank test. A spatial analysis for comparing center of mass (COM) (i.e. isocenter) coordinates for each imaging method was also performed using multivariate analysis of variance. Results: The MIP-defined mGTVs were significantly larger than both the helical- (p 0.001) and AI-defined mGTVs (p = 0.012). A comparison of COM coordinates demonstrated no significant spatial difference in the x-, y-, and z-coordinates for each tumor as determined by helical, MIP, or AI imaging methods. Conclusions: In order to incorporate the extent of tumor motion from breathing during SBRT, MIP is superior to either helical or AI images for defining the mGTV. The spatial isocenter coordinates for each tumor were not altered significantly by the imaging methods

  3. Ectopic origin of bronchial arteries: assessment with multidetector helical CT angiography

    International Nuclear Information System (INIS)

    Hartmann, Ieneke J.C.; Remy-Jardin, Martine; Menchini, Laura; Teisseire, Antoine; Khalil, Chadi; Remy, Jacques

    2007-01-01

    The purpose of this study was to determine non-invasively the frequency of ectopic bronchial arteries (BA) (i.e., bronchial arteries originating at a level of the descending aorta other than T5-T6 or from any aortic collateral vessel) on multidetector-row CT angiograms (CTA) obtained in patients with hemoptysis. Over a 5-year period (2000-2005), 251 consecutive patients with hemoptysis underwent multidetector-row CT angiography of the thorax. From this population, 37 patients were excluded because of a suboptimal CTA examination (n = 19), the presence of extensive mediastinal disease (n = 15) or severe chest deformation (n = 3) precluding any precise analysis of the bronchial arteries at CTA. Our final study group included 214 patients who underwent a thin-collimated CT angiogram (contrast agent: 300 to 350 mg/ml) on a 4- (n = 56), 16- (n = 119) and 64- (n = 39) detector-row scanner. The site of origin and distribution of bronchial arteries were analyzed on transverse CT scans, maximum intensity projections and volume-rendered images. The site of the ostium of a bronchial artery was coded as orthotopic when the artery originated from the descending aorta between the levels of the fifth and sixth thoracic vertebrae; all other bronchial arteries were considered ectopic. From the studied population, 137 (64%) patients had only orthotopic bronchial arteries, whereas 77 patients (36%) had at least one bronchial artery of ectopic origin. A total of 147 ectopic arteries were depicted, originating as common bronchial trunks (n = 23; 19%) or isolated right or left bronchial arteries (n = 101; 81%). The most frequent sites of origin of the 124 ostiums were the concavity of the aortic arch (92/124; 74%), the subclavian artery (13/124; 10.5%) and the descending aorta (10/124; 8.5%). The isolated ectopic bronchial arteries supplied the ipsilateral lung in all but three cases. Bronchial artery embolization was indicated in 26 patients. On the basis of CTA information, (1

  4. Diagnostic value of dual section helical CT in suspected acute pulmonary embolism

    International Nuclear Information System (INIS)

    Marangoni, Alberto A.; Torrecillas, Maria D.; Marchegiani, Silvio H.; Surur, Alberto

    2003-01-01

    Purpose: To asses the role of Dual Section Helical Computed Tomography (DSHCT) in patients with clinically suspected acute pulmonary embolism (APE). Material and Methods: A retrospective evaluation of 102 patients (57 male, 45 female; age range: 30-83 years; mean: 56 years) with high suspicion of APE studied by DSHCT, was carried out. From the medical records we analyzed clinical parameters, blood gases, D-dimer, risk factors and other imaging examinations. US Doppler of the inferior limbs was performed in 58/102 patients (57%). Results. 52 patients (51%) had APE on DSHCT. Scans of the other 50 patients (49%) were negative for APE. In 39/50 cases (78%) without evidence of APE, DSHCT detected ancillary thoracic findings such as atelectasia (n=11), pulmonary consolidation/edema (n=10), interstitial lung disease (n=8), pleural effusion (n=6), emphysema (n=2), nodules (n=2). 11 cases (22%) DSHCT showed no abnormal features. In this group, with persistent clinical symptoms, angio MRI showed 2 additional cases of APE (false negatives on DSHCT). On DSHCT 51/52 patients (98%) with APE showed satisfactory filling of iodinate contrast in segmental pulmonary arteries, and 45/52 patients (87%) in sub segmental arteries. On DSHCT 36 patients showed bilateral APE, and 7 had isolated peripheral APE. In 7/12 patients DSHCT demonstrated deep venous thrombosis (DVT) of the inferior limbs. In other 27/58 cases (47%) US Doppler was positive for DVT. Conclusion: DSHCT can be effectively used to rule out suspected APE and also provides additional information in patients without APE. In addition DSHCT also contributes to demonstrate deep venous thrombosis. (author)

  5. Dual-source CT in chest pain diagnosis

    International Nuclear Information System (INIS)

    Johnson, Thorsten R.C.; Nikolaou, K.; Fink, C.; Rist, C.; Reiser, M.F.; Becker, C.R.; Becker, A.; Knez, A.

    2007-01-01

    With the depiction of pulmonary arteries, coronary arteries, and the aorta, CT angiography of the chest offers a comprehensive diagnostic work-up of unclear chest pain. The aim of this study was to assess the diagnostic accuracy of dual-source CT in this patient group. A total of 47 patients suffering from unclear chest pain were examined with a Siemens Somatom Definition. Volume and flow of contrast media (Ultravist, Schering) were adapted to the body weight. The examinations were evaluated with regard to image quality and contrast opacification and to the diagnostic accuracy with reference to the final clinical diagnosis. Adequate contrast opacification was achieved in all examinations. The depiction of the coronary arteries was diagnostic in all cases. The cause of chest pain could be identified in 41 cases. Among the diagnoses were coronary and myocardial pathologies, valvular disease, aortic aneurysms and dissections, pulmonary embolism, and pneumonic consolidation. DSCT angiography of the chest offers a very good image quality even at high heart rates so that a high diagnostic accuracy is achieved in patients with acute chest pain. (orig.) [de

  6. Reformatted CT diagnosis of pituitary microadenomas in hyperprolactinemic women

    International Nuclear Information System (INIS)

    Sakamoto, Tetsuya; Kikuchi, Kenji; Kowada, Masayoshi; Hariu, Mineko; Miyauchi, Koji

    1983-01-01

    The CT diagnosis of pituitary microadenomas was made in 13 among 20 female sterile patients with hyperprolactinemia, utilizing sagittal- and coronal-sectioned reformation on the basis of 1.5 mm-sliced high-resolution axial CT scanning. The pituitary stalk was found to have been shifted in 10 patients, and in all of them adenomas were verified. This was in contrast to the findings that, among another 10 patients with no definite evidence of the stalk shifting, only 3 patients had adenomas. Pituitary adenomas were present in 11 of the 12 patients demonstrating the pituitary suface in a ''convex'' fashion. In contrast, 2 among 6 patients with a ''flat'' surface demonstrated the presence of pituitary adenomas. Enhancement patterns in the sella could be classified as of four types: homogeneous, diffuse-low, punched-out, and nodular types. The adenomas tended to occur in either the nodular or diffuse-low type; they were less frequently seen in the punched-out or homogeneous type. With regard to the correlation between the patterns of contrast enhancement and the serum concentrations of prolactin, it may be of note that the nodular type corresponded well to the higher prolactin serum level, and the homogeneous type to the lower level. (author)

  7. Diagnosis of arterial sequestration using multidetector CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Yu Hong, E-mail: yuhong.2002@hotmail.com [Department of Radiology, Changzheng Hospital, Second Military Medical University, Shanghai, 200003 (China); Li Huimin, E-mail: lihuiminphd@163.com [Department of Radiology, Changzheng Hospital, Second Military Medical University, Shanghai, 200003 (China); Liu Shiyuan, E-mail: cjr.liushiyuan@vip.163.com [Department of Radiology, Changzheng Hospital, Second Military Medical University, Shanghai, 200003 (China); Xiao Xiangsheng, E-mail: cjr.xxsh@vip.163.com [Department of Radiology, Changzheng Hospital, Second Military Medical University, Shanghai, 200003 (China)

    2010-11-15

    Background: Arterial sequestration is a rare congenital disorder. The diagnostic evaluation of this condition using multidetector computerized tomography (MDCT) has not been described previously. The purpose of this study was to describe the characteristic features of this disorder and to assess the use of MDCT in visualizing the characteristic anatomic features. Methods: We retrospectively reviewed the records of seven patients with anomalous systemic blood supply to left lower lobe of the lung. All the patients had undergone MDCT angiography. To evaluate the lung parenchyma, bronchial branching pattern, and vascular anatomy, four series of images were systematically reconstructed as follows: contiguous transverse CT scans viewed at mediastinal and pulmonary window settings, oblique coronal and sagittal maximum intensity projections (MIP), multiplanar reconstruction (MPR), and three-dimensional volume-rendered images (VR) of airway and thoracic vascular structures. Results: All 7 cases had isolated and tortuous arterial anatomy from the descending thoracic aorta to the basal segment of the left lower lobe; however, variable distribution of branches was observed. Characteristic findings of anomalous systemic arterial (ASA) supply were distinct from those seen in other pulmonary sequestration syndromes and were well visualized by the use of noninvasive MDCT. Conclusion: Complex CT findings allow clear imaging of arterial sequestration and the ASA blood supply; MDCT angiography has demonstrated its value and accuracy in diagnosing this condition, obviating the use of digital subtraction angiography and magnetic resonance angiography for the diagnosis of arterial sequestration.

  8. Diagnosis of arterial sequestration using multidetector CT angiography

    International Nuclear Information System (INIS)

    Yu Hong; Li Huimin; Liu Shiyuan; Xiao Xiangsheng

    2010-01-01

    Background: Arterial sequestration is a rare congenital disorder. The diagnostic evaluation of this condition using multidetector computerized tomography (MDCT) has not been described previously. The purpose of this study was to describe the characteristic features of this disorder and to assess the use of MDCT in visualizing the characteristic anatomic features. Methods: We retrospectively reviewed the records of seven patients with anomalous systemic blood supply to left lower lobe of the lung. All the patients had undergone MDCT angiography. To evaluate the lung parenchyma, bronchial branching pattern, and vascular anatomy, four series of images were systematically reconstructed as follows: contiguous transverse CT scans viewed at mediastinal and pulmonary window settings, oblique coronal and sagittal maximum intensity projections (MIP), multiplanar reconstruction (MPR), and three-dimensional volume-rendered images (VR) of airway and thoracic vascular structures. Results: All 7 cases had isolated and tortuous arterial anatomy from the descending thoracic aorta to the basal segment of the left lower lobe; however, variable distribution of branches was observed. Characteristic findings of anomalous systemic arterial (ASA) supply were distinct from those seen in other pulmonary sequestration syndromes and were well visualized by the use of noninvasive MDCT. Conclusion: Complex CT findings allow clear imaging of arterial sequestration and the ASA blood supply; MDCT angiography has demonstrated its value and accuracy in diagnosing this condition, obviating the use of digital subtraction angiography and magnetic resonance angiography for the diagnosis of arterial sequestration.

  9. Bone changes in the condylar head and mandibular fossa in patients with temporomandibular disorders. Helical CT observation

    International Nuclear Information System (INIS)

    Shimahara, Satoru; Ariyoshi, Yasunori; Kimura, Yoshihiro; Shimahara, Masashi

    2011-01-01

    In the present study, we investigated whether bone changes are present in sites impossible to observe by panoramic X-ray and Schuller's X-ray examination, namely the medial of the condylar head and mandibular fossa, in patients with type IV temporomandibular joint disorders. We observed the articular fossa using computed tomography, which is able to obtain detailed 3-dimensional information, in patients with type IV temporomandibular disorders. We examined 120 joints of 60 patiens who visited the Department of Oral Surgery, Osaka Medical College Hospital. Each condylar head was clearly visualized in panoramic X-ray and Schuller's X-ray examination findings, and shown to have possible changes unilaterally. Each joint was diagnosed as type IV, according to the diagnostic guidelines set by Japanese Society for Temporomandibular Joint, and further examined using helical CT. Changes in condylar head; We concluded that bone changes were present with considerable probability in the medial of condylar head in a manner similar to those found in the lateral and center of joints with type IV temporomandibular disorders. Changes in mandibular fossa; The bone changes occurred in various locations of the mandibular fossa, while they appeared significantly more frequently in the condylar head. We think that our finding will contribute to development of treatment strategies for temporomandibular disorders, as they clarify bone changes in sites previously unreported. (author)

  10. Detection and localization of acute upper and lower gastrointestinal (GI) bleeding with arterial phase multi-detector row helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Jaeckle, T.; Stuber, G.; Hoffmann, M.H.K.; Jeltsch, M.; Schmitz, B.L.; Aschoff, A.J. [University Hospital of Ulm, Diagnostic and Interventional Radiology, Ulm (Germany)

    2008-07-15

    The purpose of this study was to evaluate the accuracy of multi-detector row helical CT (MDCT) for detection and localization of acute upper and lower gastrointestinal (GI) hemorrhage or intraperitoneal bleeding. Thirty-six consecutive patients with clinical signs of acute bleeding underwent biphasic (16- or 40-channel) MDCT. MDCT findings were correlated with endoscopy, angiography or surgery. Among the 36 patients evaluated, 26 were examined for GI bleeding and 10 for intraperitoneal hemorrhage. Confirmed sites of GI bleeding were the stomach (n = 5), duodenum (n = 5), small bowel (n = 6), large bowel (n = 8) and rectum (n = 2). The correct site of bleeding was identifiable on MDCT in 24/26 patients with GI bleeding. In 20 of these 24 patients, active CM extravasation was apparent during the exam. Among the ten patients with intraperitoneal hemorrhage, MDCT correctly identified the bleeding source in nine patients. Our findings suggest that fast and accurate localization of acute gastrointestinal and intraperitoneal bleeding is achievable on MDCT. (orig.)

  11. Detection and localization of acute upper and lower gastrointestinal (GI) bleeding with arterial phase multi-detector row helical CT

    International Nuclear Information System (INIS)

    Jaeckle, T.; Stuber, G.; Hoffmann, M.H.K.; Jeltsch, M.; Schmitz, B.L.; Aschoff, A.J.

    2008-01-01

    The purpose of this study was to evaluate the accuracy of multi-detector row helical CT (MDCT) for detection and localization of acute upper and lower gastrointestinal (GI) hemorrhage or intraperitoneal bleeding. Thirty-six consecutive patients with clinical signs of acute bleeding underwent biphasic (16- or 40-channel) MDCT. MDCT findings were correlated with endoscopy, angiography or surgery. Among the 36 patients evaluated, 26 were examined for GI bleeding and 10 for intraperitoneal hemorrhage. Confirmed sites of GI bleeding were the stomach (n = 5), duodenum (n = 5), small bowel (n = 6), large bowel (n = 8) and rectum (n = 2). The correct site of bleeding was identifiable on MDCT in 24/26 patients with GI bleeding. In 20 of these 24 patients, active CM extravasation was apparent during the exam. Among the ten patients with intraperitoneal hemorrhage, MDCT correctly identified the bleeding source in nine patients. Our findings suggest that fast and accurate localization of acute gastrointestinal and intraperitoneal bleeding is achievable on MDCT. (orig.)

  12. Volume-artifact reduction modality by helical CT of the anterior, middle and posterior carnial fossae. Comparison with conventional CT; Volumen-Artefakt-Reduktionstechnik mittels Spiral-CT in der vorderen, mittleren und hinteren Schaedelgrube. Vergleich mit der konventionellen kranialen CT

    Energy Technology Data Exchange (ETDEWEB)

    Dorenbeck, U.; Finkenzeller, T.; Hill, K.; Feuerbach, S.; Link, J. [Regensburg Univ. (Germany). Inst. fuer Roentgendiagnostik

    2000-04-01

    Purpose: The object of this study was to determine the extent to which a new volume-artifact reduction (VAR) modality using helical CT was able to reduce artifacts in the anterior, middle and posterior fossae in comparison with conventional CT (sequential mode). Methods: In a prospective, randomized trial, 50 patients underwent helical CT (VAR) and 50 underwent sequential CT. The results were evaluated by three radiologists; influences on image quality where scaled between 1 (no artifact) and 4 (not assessable). Eight regions of the anterior, middle and posterior fossae were evaluated. Results: On average, artifacts were scaled at 2.5 in helical CT (VAR) and 3.1 in conventional CT. Significant differences were seen at the eyeball, anterior to the petrosol bone, at the internal occipital crest, and at the level of the transverse sinus (p<0.005). Conclusions: Helical CT with the VAR modality is superior to conventional, sequential CT in the area of the anterior, middle and posterior fossae. (orig.) [German] Ziel: Das Ziel dieser Studie war herauszufinden, inwieweit ein neuer Volumen-Artefakt-Reduktionsmodus (VAR) im Spiral-CT in der vorderen, mittleren und hinteren Schaedelgrube gegenueber der Einzelschicht-CT zu einer Artefaktverringerung beitragen kann. Methoden: In einer prospektiven randomisierten Studie wurden 50 Untersuchungen mit Spiral-CT und 50 mit Einzelschicht-CT bezueglich Artefakten verglichen. Die Auswertung erfolgte durch drei Radiologen, die Bildqualitaet wurde in einer Skala zwischen 1 (kein Artefakt) und 4 (Beurteilung der Region wegen Artefakten nicht moeglich) angegeben. Acht anatomische Regionen in der vorderen, mittleren und hinteren Schaedelgrube wurden auf Beeintraechtigung durch Artefakte untersucht. Ergebnisse: Im Durchschnitt betrug die Bewertung fuer die Artefaktbeeintraechtigung beim Spiral-CT (VAR) 2,5 gegenueber 3,1 bei der Einzelschicht-CT. Der VAR-Modus ermoeglichte in der mittleren und hinteren Schaedelgrube sowie im Balbus oculi

  13. The detectability of hepatic metastases in candidates of radiofrequency ablation: comparison for helical CT scanning and late-phase pulse-inversion harmonic imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kang Won; Yoon, Kwon Ha; Kim, Eun A; Park, Ki Han; Juhng, Seon Kwan; Won, Jong Jin [School of Medicine, Wonkwang Univ., Iksan (Korea, Republic of)

    2002-02-01

    To compare dual-phase helical CT and pulse inversion harmonic US using microbubble contrast agents in the detection of hepatic metastases prior to radiofrequency (RF) ablation. Twenty-one patients in whom hepatic metastases from colorectal cancer had been diagnosed by dual-phase CT scanning and who were considered to be candidates for RF ablation underwent pulse-inversion barmonic US examination. Images were obtained 5 minutes after the bolus injection of microbubble contrast agent SH U 508 A (4.0 g, 300 mg/mL). The number of metastatic tumors revealed by CT and US was determined, and the findings were statistically analysed. The influence of the results of US examination on treatment planning was also evaluated. In 21 patients, 48 metastaic lesions were detected by helical CT, and 56 lesions by US. These eight additional lesions revealed by US occurred in six patients (29%), and their diameter was 3-13 (mean, 7.2) mm. In three of these patients, RF ablation could not be performed ,while in the other three, the additional lesions were ablated. Pulse-inversion harmonic US imaging using microbubble contrast agents may depict small hepatic metastatic tumors that were not apparent at CT. US-therefore appears to be useful in the planning of treatment prior to the RF ablation of hepatic metastases.

  14. Coronary artery calcification detected by a mobile helical CT unit in a mass screening. The frequency and relationship to coronary risk factors and coronary artery disease

    Energy Technology Data Exchange (ETDEWEB)

    Itani, Yasutaka; Watanabe, Shigeru; Masuda, Yoshiaki [Chiba Univ. (Japan). School of Medicine; Hanamura, Kazuhisa; Asakura, Kazuhiro; Sone, Shusuke; Sunami, Yuko; Shimura, Akimitsu; Miyamoto, Tadaaki

    2001-06-01

    A strong relationship is known to exist between coronary artery disease (CAD) and coronary artery calcification (CAC) detected by CT. In this study, we investigated the frequency of CAC and the relationship between coronary risk factors, CAD and CAC in a mass screening using a mobile helical CT unit. The total number of participants was 10008 people undergoing a medical examination for lung cancer and tuberculosis using a mobile helical CT unit. We measured the CT density of the coronary artery to detect CAC. The CT density threshold for determining CAC was above +110HU. The frequency of CAC was 16.0% in the overall patient population and significantly higher in males than in females (20.6% vs 10.7%). Frequency increased with age in both genders. Hypertension and diabetes mellitus were significantly related to CAC. Smoking showed a correlation with CAC only in males. A significant relationship was observed between CAD and CAC in males. In particular, the relationship between them was strongest in males under 60 years of age. Furthermore, the odds ratio of CAC in predicting CAD increased with increasing risk factors in both genders. (author)

  15. What is the complementary role of ultrasound evaluation in the diagnosis of acute appendicitis after CT?

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Kyung Mi [Department of Radiology, Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Lee, Kwanseop [Department of Radiology, Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of)], E-mail: kwanseop@hallym.or.kr; Kim, Min-Jeong; Yoon, Hoi Soo; Jeon, Eui Yong; Koh, Sung Hye [Department of Radiology, Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Min, Kwangseon [Department of Pathology, Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Choi, Dongil [Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine (Korea, Republic of)

    2010-04-15

    The objective of our study was to estimate the complementary role of ultrasound evaluation in the diagnosis of acute appendicitis after abdominoplevic CT. A total of 104 patients initially underwent abdominopelvic CT before appendix US due to acute abdominal pain. All CT examinations were evaluated retrospectively for the presence of acute appendicitis. The findings of appendix on CT were classified into five categories (definite appendicitis, probably appendicitis, equivocal CT findings for diagnosis of appendicitis, probably not appendicitis, and normal looking appendix). Appendix US images and their radiologic reports were also evaluated retrospectively. Then, CT and US findings were correlated with clinical or pathologic diagnosis. Three all patients with definite appendicitis initially on CT again showed US findings of appendicitis. In the 32 patients of probably appendicitis on CT, US showed normal looking appendix in seven patients (21.8%, 7 of 32) who improved with medical treatment and discharged. In the 16 patients of equivocal CT findings for diagnosis of appendicitis, US showed appendicitis in seven patients (43.8%, 7 of 16) and normal looking appendix in nine patients. In the 12 patients of probably not appendicitis on CT, US showed acute appendicitis in two patients (16.7%, 2 of 12). In the 41 patients of normal looking appendix on CT, US showed acute appendicitis in five patients (12.2%, 5 of 41). US reevaluation enables us to avoid misdiagnosis of appendicitis on CT and improve diagnostic accuracy of acute appendicitis.

  16. Multiple renal aspergillus abscesses in an AIDS patient: contrast-enhanced helical CT and MRI findings

    International Nuclear Information System (INIS)

    Heussel, C.P.; Kauczor, H.U.; Thelen, M.; Heussel, G.; Jahn, B.

    1999-01-01

    Renal insufficiency or allergic reactions for X-ray contrast agents are frequent limitations in immunocompromised hosts such as neutropenic or AIDS patients. Due to a better tolerance of contrast agents in MRI, this technique is well suited for investigation of parenchymal organs. We demonstrate an allergic AIDS patient who presented with fever and flank pain. At sonography, anechoic renal lesions were supposed to be non-complicated cysts; however, on T2-weighted MRI, the center was of high signal. Dynamic contrast-enhanced MRI of the kidneys demonstrated an enhancing rim with ill-defined margins. The lesions were supposed to be multiple bilateral abscesses. Due to the multiple dynamic contrast series, a delayed enhancement of renal parenchyma was detectable adjacent to the lesion. This was suggested as accompanying local pyelonephritis and an infectious etiology became more reliable. Aspergillus fumigatus was identified by CT-guided biopsy as the underlying microorganism. The MR appearance of this manifestation has not been described previously. (orig.)

  17. The clinical significance of CT in the preoperative diagnosis of colon and rectal cancer

    International Nuclear Information System (INIS)

    Itano, Satoshi; Fuchimoto, Sadanori; Hamada, Fumihiro; Kimura, Takanobu; Orita, Kunzo

    1986-01-01

    The clinical significance of CT in the preoperative diagnosis of colon and rectal cancer was studied. Thirty four patients were investigated in this series. The diagnostic criteria of the CT examination were previously established in a study of wall invasion (S factor), lymph node metastasis (N factor), liver metastasis (H factor) and peritoneal dissemination (P factor). The CT diagnosis was done prospectively according to these criteria, and the CT diagnosis was compared with the macroscopic and histological diagnosis. The accuracy of the prospective diagnosis as to H, S, N and P factors was 79.4 %, 55.9 %, 41.2 % and 20.6 %, respectively. The diagnostic value of CT seemed to be acceptable as to the H factor, but limited to some extent to the S and N factors. (author)

  18. Posterior reversible encephalopathy syndrome: diagnosis with CT and MRI

    International Nuclear Information System (INIS)

    Wang Guangbin; Zhao Bin; Yang Zhenzhen; Shi Hao; Chiu, L.C.; Shan Ruiqin

    2006-01-01

    Objective: To evaluate the role of CT and MRI in the diagnosis of posterior reversible encephalopathy syndrome (PRES). Methods: Eight women with PRES (6 pregnant women, 1 case after chemotherapy, and 1 patient with hypertension)were enrolled in our study. All of them had MR imaging (T 1 WI, T 2 WI, FLAIR, DWI), and five cases underwent post-contrast T 1 WI and three dimensional contrast enhanced MR angiography (3D CEMRA). Two cases also had CT scan. Results: MRV in all 8 patients showed no evidence of stenosis, dilation, or thrombosis in cranial veins and sinuses. MRI demonstrated multiple lesions located in bilateral parieto-occipital lobes (8 cases), bilateral basal ganglia (2 cases), and bilateral frontal lobes (4 cases). The lesions were prominent within white matter, some of them involved gray matter (3 cases). Lesions appeared as hyperintense signals on FLAIR and T 2 -weighted images, isointense or mildly hypointense signals on T 1 -weighted images, normal or decreased intensity on DWI, and isointensity or hyperintensity on apparent diffusion coefficient (ADC) maps. Post-contrast T 1 WI showed mild reversible enhancement and 3D CEMRA displayed numerous reversible 'grape-like' enhancements in terminal arterial branches along the middle cerebral artery (MCA), anterior cerebral artery (ACA) and posterior cerebral artery (PCA). Follow-up scan showed decreased abnormal signals. Conclusion: Lesions of PRES are usually located in parieto-occipital lobes, especially in white matter, but they can also be seen in frontal lobes and basal ganglia bilaterally. Post-contrast T 1 WI and 3D enhanced MRA can provide useful information in the manifestation of reversible enhancement. MRI has advantages to display lesion in PRES. (authors)

  19. Intracerebral lymphoma with two patients. CT and MRI diagnosis

    International Nuclear Information System (INIS)

    Yanakiev, A.; Popovska, T.; Zasheva, I.

    2012-01-01

    Full text: Lymphoma (Hodgkin's and non-Hodgkin's) is a disease of the lymphatic system where the central neural system is affected in very rare cases. According to different authors the frequency of cases with lymphoma where the neural system is affected varies between 0.2% and 0.5%, and the primary cerebral lymphoma accounts for about 1-2% of all brain neoplasms. The intracranial form of lymphoma is usually a late onset of the disease with serious and potentially fatal complications for the patient. These complications usually appear several years after diagnosing the disease, but the cerebral lymphoma may occur even in patients who are in remission, which is actually the case with our patients. We present you two cases - a 38-year-old female and a 48-year-old male, who were hospitalized in Neuro ward with the following complaints: loss of speech for a few minutes, dizziness, weakness, tingling and shuffling of one of the legs. Those patients were diagnosed with histological B-cell non-Hodgkin's lymphoma and Hodgkin's lymphoma, several years ago. CT and MRI were carried out on the patients. Despite both clinical and radiographic suspicions for intracranial forms of lymphoma, the patients were still difficult to diagnose. A definitive diagnosis was given after a surgery and histological examination, i.e. non- Hodgkin's lymphoma - large B-cell lymphomas, and Hodgkin's lymphoma. These cases are of interest because of their rare intracranial localization of the lymphoma. The knowledge of CT and MRI images with the intracranial form of lymphoma may help diagnosing, but images should be interpreted together with the clinical and paraclinical results

  20. CT diagnosis of sellar and juxtasellar lesions, 3. Non-tumorous lesions

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Tatsuya [Nagoya Univ. (Japan). Faculty of Medicine

    1982-08-01

    A study is made of the usefulness and limitations of the CT diagnosis of sellar and juxtasellar lesions other than tumors. This study is based on 112 verified cases at Nagoya University Hospital from October, 1976, to December, 1981. The lesions included in this study are classified into four groups: vascular, inflammatory, traumatic lesion, and congenital anomaly. Although cerebral angiography is the cardinal method for the diagnosis of vascular lesions, CT is useful for the evaluation of a giant aneurysm, the localization of bleeding, or infarction by a ruptured aneurysm. Radiation brain necrosis, a special form of vascular lesion, can also be diagnosed if the critical analysis is made after previous irradiation. CT findings are helpful for the local diagnosis of acute inflammatory lesions, such as basal meningitis or abscess, but specific diagnosis is made on the basis of clinical signs and CSF study. Abnormal CT findings are obtained from a chronic inflammatory process, such as arachnoiditis adhesiva, glanuloma, or mucocele. Differential diagnosis is necessary with brain tumors. The CT findings of an arachnoid cyst are often diagnostic. Metrizamide or air cisternography, either combined with CT or without it, is important for the diagnosis of basal meningoencephalocele and hypothalamic hamaroma. Pneumocephalus and an intracranial foreign body resulting from a head injury can be diagnosed by plain skull and CT. The diagnosis of CSF leakage or prolapse cerebri associated with a skull-base fracture has been most difficult, but even it is possible by a combination of polytomography and high-resolution CT with metrizamide cisternography.

  1. Research and development of the system for group examination of lung cancer by helical CT

    International Nuclear Information System (INIS)

    2003-03-01

    For the ultimate purpose of heavy particle therapy of lung cancer at an early stage, the system in the title with low dose radiation has been investigated by cooperation of NIRS (as a leading part) and medical/industrial facilities all over the country. The project started essentially in 1984 and has been continuing at 2003. This book described Results hitherto and Materials for application to medical care at disaster (Hanshin-Awaji Earthquake Disaster in 1995) together with reference materials. Results contain all fields of nuclear medicine and of imaging involved in examination/diagnosis of lung cancer, achieved by NIRS, by Health management center and Faculty of Medicine, Chiba University and Japan Anti-Tuberculosis Association in Chiba, by the 3rd Department of Internal Medicine, Fac. Med., Chiba Univ., by Osaka Medical Center for Cancer and Cardiovascular Diseases, by Nippon Med. School, Arakawa-ku cancer protection center and Tokyo Metropolitan Univ. of Health Sciences, by Hitachi health management center, by Fukui Med. College, by Hitachi Medical Corp., by NTT research laboratories, and by Toyohashi Univ. of Technology. The Materials involve Process and summary of conducting the medical care activities, Improvement of the examination automobile, Supplementary equipments and measures for legal problems, System for the medical care activities, Record of the examination automobile activities, Problems in future, and Completion of the medical activities. Reference materials are related with the Materials above. (N.I.)

  2. Multislice helical CT analysis of small-sized airway wall thickness in smokers and patients with bronchial asthma

    International Nuclear Information System (INIS)

    Sekimura, Kenshi; Ito, Harumasa; Nakamura, Yutaka; Kobayashi, Hitoshi; Oikawa, Hirobumi; Inoue, Hiroshi; Ehara, Shigeru; Yamauchi, Kohei

    2010-01-01

    There is accumulating evidence that airway remodeling, which contributes to airway narrowing, plays a role in the pathogenesis of bronchial asthma (BA) and chronic obstructive pulmonary disease (COPD). Development of the multislice helical CT (MSCT) with improved spatial resolution has made it possible to obtain more precise imaging of small-sized airways. Small-sized airway wall-thickness was measured using the MSCT scan to analyze small-sized airways of smokers and BA patients, and examine the effects of a β 2 agonists on small-sized airway wall-thickness of BA patients. Thirty-six non-asthmatics who participated in the Health Check Program of Iwate Medical University and 25 patients with asthma were recruited. Amongst the 36 non-asthmatics were 20 healthy never-smokers and 15 smokers. The other 25 asthmatics were recruited from the outpatient clinic at Iwate Medical University. MSCT was performed and the right B10 bronchus was chosen for dimensional analysis. Airway wall thickness was expressed as a percentage of wall area (WA%). WA% of the 7 asthmatics before and 30 mim after procaterol (20μg) inspiration were compared. Small-sized airway wall thickness was significantly increased in smokers and patients with asthma compared to healthy never-smokers, when determined by MSCT. Both %V 50 and %V 25 had significant negative correlations with WA% among the healthy never-smokers and smoker population. Procaterol inspiration reduced WA% in the small airway of patients with asthma. Increase of small-sized airway thickness measured by MSCT scan may reflect peripheral obstructive lesions of smokers and BA patients. (author)

  3. Comparison of the effectiveness of different immobilization systems in different body regions using daily megavoltage CT in helical tomotherapy

    Science.gov (United States)

    Cheng, K-F

    2014-01-01

    Objective: Effective immobilization is crucial for the accurate delivery of radiotherapy. This study aimed to compare the effectiveness of the commonly used immobilization systems for different body regions using megavoltage CT (MVCT). Methods: Daily treatment set-up data from 212 patients treated by helical tomotherapy (Accuray, Sunnyvale, CA) in 6 body regions (52 head and neck, 41 chest, 38 abdomen, 36 pelvis, 18 breast and 27 cranium) were obtained. Based on a verification tool using the pre-treatment MVCT, set-up corrections for each patient were recorded. Mean systematic and random errors of lateral, longitudinal, vertical and roll directions and three-dimensional vectors were compared between immobilization systems of each region. Results: Smaller set-up deviations were observed in the Orfit system (Orfit Industries NV, Wijnegem, Belgium) of the head and neck region, while the performance of immobilization systems for the chest, abdomen and pelvis regions was similar. Larger differences were noted in the breast group, where the prone BodyFIX® system (Medical Intelligence, Medizintechnik GmbH, Schwabmünchen, Germany) was less stable than the supine VacLok® system (CIVCO Medical Solutions, Orange City, IA). Conclusion: Differences were found between the immobilization systems in the head and neck region, in which the Orfit system was relatively more effective, whereas the VacLok and BodyFIX systems performed similarly in the chest, abdomen and pelvis regions. For the breast case, the supine position with VacLok was much more stable than the prone breast technique. The results provided references for the estimation of clinical target volume–planning target volume margins. Advances in knowledge: This is the first article on comprehensive comparisons performed in immobilization systems for main body regions that provides some practical recommendations. PMID:24398111

  4. Suitability of helical multislice acquisition technique for routine unenhanced brain CT: an image quality study using a 16-row detector configuration

    Energy Technology Data Exchange (ETDEWEB)

    Hernalsteen, Danielle; Cosnard, Guy; Grandin, Cecile; Duprez, Thierry [Universite Catholique de Louvain, Cliniques Universitaires Saint-Luc, Department of Radiology and Medical Imaging, Brussels (Belgium); Robert, Annie [Public Health School, Universite Catholique de Louvain, Department of Epidemiologics and Medical Statistics, Brussels (Belgium); Vlassenbroek, Alain [CT Clinical Science, Philips Medical Systems, Cleveland, OH (United States)

    2007-04-15

    Subjective and objective image quality (IQ) criteria, radiation doses, and acquisition times were compared using incremental monoslice, incremental multislice, and helical multislice acquisition techniques for routine unenhanced brain computed tomography (CT). Twenty-four patients were examined by two techniques in the same imaging session using a 16-row CT system equipped with 0.75-width detectors. Contiguous ''native'' 3-mm-thick slices were reconstructed for all acquisitions from four detectors for each slice (4 x 0.75 mm), with one channel available per detector. Two protocols were tailored to compare: (1) one-slice vs four-slice incremental images; (2) incremental vs helical four-slice images. Two trained observers independently scored 12 subjective items of IQ. Preference for the technique was assessed by one-tailed t test and the interobserver variation by two-tailed t test. The two observers gave very close IQ scores for the three techniques without significant interobserver variations. Measured IQ parameters failed to reveal any difference between techniques, and an approximate half radiation dose reduction was obtained by using the full 16-row configuration. Acquisition times were cumulatively shortened by using the multislice and the helical modality. (orig.)

  5. Suitability of helical multislice acquisition technique for routine unenhanced brain CT: an image quality study using a 16-row detector configuration

    International Nuclear Information System (INIS)

    Hernalsteen, Danielle; Cosnard, Guy; Grandin, Cecile; Duprez, Thierry; Robert, Annie; Vlassenbroek, Alain

    2007-01-01

    Subjective and objective image quality (IQ) criteria, radiation doses, and acquisition times were compared using incremental monoslice, incremental multislice, and helical multislice acquisition techniques for routine unenhanced brain computed tomography (CT). Twenty-four patients were examined by two techniques in the same imaging session using a 16-row CT system equipped with 0.75-width detectors. Contiguous ''native'' 3-mm-thick slices were reconstructed for all acquisitions from four detectors for each slice (4 x 0.75 mm), with one channel available per detector. Two protocols were tailored to compare: (1) one-slice vs four-slice incremental images; (2) incremental vs helical four-slice images. Two trained observers independently scored 12 subjective items of IQ. Preference for the technique was assessed by one-tailed t test and the interobserver variation by two-tailed t test. The two observers gave very close IQ scores for the three techniques without significant interobserver variations. Measured IQ parameters failed to reveal any difference between techniques, and an approximate half radiation dose reduction was obtained by using the full 16-row configuration. Acquisition times were cumulatively shortened by using the multislice and the helical modality. (orig.)

  6. CT diagnosis of primary lung cancer coexisting with pulmonary tuberculosis

    International Nuclear Information System (INIS)

    Kim, Sun Joo; Kim, Young Sook; Oh, Jae Hee; Kim, Eun Kyoung; Kim, Young Chul

    1992-01-01

    When bronchogenic carcinoma is coexisting with pulmonary tuberculosis, it is difficult to differentiate bronchogenic carcinoma from pulmonary tuberculosis radiographically. Thus, the object of this study is to define differential diagnosis of bronchogenic carcinoma by computed tomography. We analyzed CT scans of 27 patients with radiologic findings of pulmonary tuberculosis and mass of which twelve cases were pulmonary tuberculosis and fifteen cases were primary lung cancer. The location of parenchymal infiltration and the mass was the same in 60%(9/15) of the primary lung cancer in cases and 83%(10/12) of the pulmonary tuberculosis cases. The common location of the mass was the both upper lobes in 92%(11/12) of the pulmonary tuberculosis cases and 53%(8/15) of the primary lung cancer cases. The common locations of the mediastinal lymphadenopathy were 4R, 2R of the pulmonary tuberculosis cases and 4R, 10R of the primary lung cancer cases. In the feature of post enhanced lymph nodes, homogenous increased density was more frequent in primary lung cancer. Measurements of the maximum thickness part of the cavity wall was not a reliable indication of malignancy

  7. CT diagnosis of unsuspected pneumothorax after blunt abdominal trauma

    Energy Technology Data Exchange (ETDEWEB)

    Wall, S.D. (Univ. of California, San Francisco); Federle, M.P.; Jeffrey, R.B.; Brett, C.M.

    1983-11-01

    Review of abdominal CT scans for evaluation of blunt abdominal trauma yielded 35 cases of pneumothorax, 10 of which had not been diagnosed before CT by clinical examination of plain radiographs. Of the 10 cases initially diagnosed on CT, seven required tube thoracostomy for treatment of the pneumothorax. CT detection of pneumothorax is especially important if mechanical assisted ventilation or general anesthesia is used. Demonstration of pneumothorax requires viewing CT scans of the upper abdomen (lower thorax) at lung windows in addition to the usual soft-tissue windows.

  8. CT diagnosis of unsuspected pneumothorax after blunt abdominal trauma

    International Nuclear Information System (INIS)

    Wall, S.D.; Federle, M.P.; Jeffrey, R.B.; Brett, C.M.

    1983-01-01

    Review of abdominal CT scans for evaluation of blunt abdominal trauma yielded 35 cases of pneumothorax, 10 of which had not been diagnosed before CT by clinical examination of plain radiographs. Of the 10 cases initially diagnosed on CT, seven required tube thoracostomy for treatment of the pneumothorax. CT detection of pneumothorax is especially important if mechanical assisted ventilation or general anesthesia is used. Demonstration of pneumothorax requires viewing CT scans of the upper abdomen (lower thorax) at lung windows in addition to the usual soft-tissue windows

  9. Diagnosis of Grave's disease with pulmonary hypertension on chest CT.

    Science.gov (United States)

    Lee, Hwa Yeon; Yoo, Seung Min; Kim, Hye Rin; Chun, Eun Ju; White, Charles S

    To evaluate the diagnostic accuracy of chest CT findings to diagnose Grave's disease in pulmonary hypertension. We retrospectively evaluated chest CT and the medical records of 13 patients with Grave's disease with (n=6) or without pulmonary hypertension (n=7) and in 17 control patients. Presence of iso-attenuation of diffusely enlarged thyroid glands compared with adjacent neck muscle on non-enhanced CT as a diagnostic clue of Grave's disease, and assessment of pulmonary hypertension on CT has high diagnostic accuracy. Chest CT has the potential to diagnose Grave's disease with pulmonary hypertension in the absence of other information. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Dual phase helical CT versus portal venous phase CT for the detection of colorectal liver metastases: Correlation with intra-operative sonography, surgical and pathological findings

    International Nuclear Information System (INIS)

    Scott, D. John; Guthrie, J. Ashley; Arnold, Paul; Ward, Janice; Atchley, Julian; Wilson, Daniel; Robinson, Philip J.

    2001-01-01

    AIM: To assess whether dual phase helical computed tomography (DPCT) of the liver improves the detection of colorectal liver metastases compared with portal venous phase (PVP) imaging alone. MATERIALS AND METHODS: DPCT was performed in 33 consecutive patients before laparotomy for resection of colorectal liver metastases. CT comprised 8-mm slice collimation with a pitch of 1 to 1.25; imaging was commenced 20-25 and 65-70 s after the start of injection of 150 ml of contrast medium at 5 ml/s to coincide with hepatic arterial phase (HAP) and PVP contrast enhancement, respectively. Four blinded observers independently reviewed the HAP, PVP and DPCT images recording the site and size of all lesions. Alternative-free response receiver operating characteristic (AFROC) methodology was used to analyse the results, which were correlated with surgery, intra-operative ultrasound and histology. RESULTS: The mean observer sensitivities for malignant lesion detection were 75.3% for DPCT, 69.7% for PVP imaging and 66.7% for HAP imaging alone. There was a statistically significant improvement in malignant lesion detection using DPCT when compared with PVP imaging alone (P < 0.05). The mean areas under the AFROC curves were 0.84 for DPCT and 0.82 for PVP (P < 0.03) imaging alone. CONCLUSION: The detection of colorectal liver metastases was marginally better with DPCT than with PVP imaging alone, but the discovery of additional lesions did not affect the management of any of the patients in this study. Scott, D.J. et al. (2001)

  11. Multislice helical CT (MSCT) for mid-facial trauma: optimization of parameters for scanning and reconstruction; Mehrschicht-Spiral-CT (MSCT) beim Mittelgesichtstrauma: Optimierung der Aufnahme- und Rekonstruktionsparameter

    Energy Technology Data Exchange (ETDEWEB)

    Dammert, S.; Funke, M.; Obernauer, S.; Grabbe, E. [Abt. Roentgendiagnostik I, Georg-August-Univ. Goettingen (Germany); Merten, H.A. [Abt. fuer Mund-, Kiefer- und Gesichtschirurgie, Georg-August-Univ. Goettingen (Germany)

    2002-07-01

    Purpose: To determine the optimal scan parameters in multislice helical CT (MSCT) of the facial bone complex for both axial scanning and multiplanar reconstructions. Material and Methods: An anthropomorphic skull phantom was examined with a MSCT. Axial scans were performed with continuously increasing collimations (4 x 1.25 - 4 x 2.5 mm), tube current (20 - 200 mA) and table speeds (3.75 mm/rot. and 7.5 mm/rot.). Multiplanar reconstructions in coronal and parasagittal planes with different reconstruction increment and slice thickness were evaluated in terms of image noise, contour artifacts and visualisation of anatomical structures. Results: The best image quality was obtained with a collimation of 4 x 1.25 mm and a - table speed of 3.75 mm/rot. A reconstruction increment of 0.6 mm achieved the best time to image quality relation. With these parameters the bone structures were depicted in an optimal way without artifacts. The tube current could be reduced to 50 mA without significant loss of image quality. The optimized protocol was used for regular routine examinations in patients with facial trauma (n = 66). Conclusions: Low-dose MSCT using thin collimation, low table speed and small reconstruction increments provides excellent data for both axial images and multiplanar reconstructions in patients with facial trauma. An additional examination in coronal orientation is therefore no longer necessary. (orig.) [German] Zielsetzung: Verbesserung der Aufnahme- und Rekonstruktionsparameter in der Mehrschicht Spiral-CT (MSCT) zur Untersuchung des knoechernen Mittelgesichtes in verschiedenen Ebenen. Material und Methode: Ein anthropomorphes Schaedel-Phantom wurde in axialer Schichtfuehrung mit einem MSCT untersucht, wobei die Kollimation (1,25 - 2,5 mm), der Tischvorschubfaktor (Pitch 3 - 6) und der Roehrenstrom (20 - 200 mA) systematisch variiert wurden. Aus den Volumendatensaetzen wurden jeweils koronare und parasagittale Sekundaerreformationen mit unterschiedlichen

  12. CT diagnosis of mediastinal tuberculous lymphadenopathy in adults

    International Nuclear Information System (INIS)

    Liu Fugeng; Pan Jishu; Wu Guogeng; Chen Qihang; Yu Jingying; Zhou Cheng

    2001-01-01

    Objective: To evaluate the features of mediastinal tuberculous lymphadenopathy in adults on CT, especially on enhanced CT scan. Methods: Seventeen patients with adult mediastinal tuberculous lymphadenopathy proved by operation, biopsy, and (or) anti-tuberculous therapy were evaluated on chest film and CT scan, and 6 patients were performed with enhanced CT scan. Results: The chest film finding was intrathoracic mass and (or) hilar mass only in 6 patients, but CT detected 37 enlarged nodes in all patients. Most of the enlarged nodes were located in 2R and (or) 4R (59.4%). 30 nodes (81.1%) presented as low-density in the center of nodes, and there were marked enhancement at the periphery areas of the nodes after enhancement in all 6 patients (100.0%). Conclusion: CT scan, especially the enhanced CT scan, is the first method of choice to diagnose the mediastinal tuberculous lymphadenopathy in adults

  13. Diagnosis of preoperative staging of bladder cancer by CT and angiography

    International Nuclear Information System (INIS)

    Munechika, Hirotsugu; Saito, Kazuhiko; Tanaka, Osamu; Tomiie, Fumitaka; Aihara, Toshinori

    1982-01-01

    The accuracy of computed tomography (CT) and angiography in defining the extent of local invasion was studied retrospectively in 19 patients with surgically proven carcinoma of the bladder. The overall accuracy of CT and angiographic staging in these cases was 54 percent and 47 percent respectively. The diagnosis of carcinoma of the bladder by CT tended to do overstaging rather than understaging. A tangential view of the tumor-bearing area by the selective internal iliac arteriography allows an accurate estimation of the perivesical tumor extension. The topographic diagnosis should be made by CT prior to the angiographic study. (author)

  14. TH-E-17A-02: High-Pitch and Sparse-View Helical 4D CT Via Iterative Image Reconstruction Method Based On Tensor Framelet

    International Nuclear Information System (INIS)

    Guo, M; Nam, H; Li, R; Xing, L; Gao, H

    2014-01-01

    Purpose: 4D CT is routinely performed during radiation therapy treatment planning of thoracic and abdominal cancers. Compared with the cine mode, the helical mode is advantageous in temporal resolution. However, a low pitch (∼0.1) for 4D CT imaging is often required instead of the standard pitch (∼1) for static imaging, since standard image reconstruction based on analytic method requires the low-pitch scanning in order to satisfy the data sufficient condition when reconstructing each temporal frame individually. In comparison, the flexible iterative method enables the reconstruction of all temporal frames simultaneously, so that the image similarity among frames can be utilized to possibly perform high-pitch and sparse-view helical 4D CT imaging. The purpose of this work is to investigate such an exciting possibility for faster imaging with lower dose. Methods: A key for highpitch and sparse-view helical 4D CT imaging is the simultaneous reconstruction of all temporal frames using the prior that temporal frames are continuous along the temporal direction. In this work, such a prior is regularized through the sparsity transform based on spatiotemporal tensor framelet (TF) as a multilevel and high-order extension of total variation transform. Moreover, GPU-based fast parallel computing of X-ray transform and its adjoint together with split Bregman method is utilized for solving the 4D image reconstruction problem efficiently and accurately. Results: The simulation studies based on 4D NCAT phantoms were performed with various pitches (i.e., 0.1, 0.2, 0.5, and 1) and sparse views (i.e., 400 views per rotation instead of standard >2000 views per rotation), using 3D iterative individual reconstruction method based on 3D TF and 4D iterative simultaneous reconstruction method based on 4D TF respectively. Conclusion: The proposed TF-based simultaneous 4D image reconstruction method enables high-pitch and sparse-view helical 4D CT with lower dose and faster speed

  15. 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.)

  16. CT urography in the diagnosis of renal masses in patients with hematuria

    International Nuclear Information System (INIS)

    Warshauer, D.M.; Street, L.; McCarthy, S.M.; Glickman, M.G.; Ritcher, J.; Rosenfield, A.T.

    1987-01-01

    The optimal method for the diagnosis of renal masses in patients with hematuria has been in question since the introduction of axial imaging techniques. A prospective study comparing excretory urography and nephrotomography (EU) with limited renal CT was undertaken. Results showed EU able to detect approximately 75% of CT-confirmed masses greater than 2 cm, but less than 10% of CT masses smaller than 2 cm. These results suggest that a combination study of CT/EU utilizing a single contrast injection with EU for imaging the collecting system and CT for renal parenchymal evaluation would be the best screening study in patients with hematuria

  17. SPECT/CT in the Diagnosis of Skull Base Osteomyelitis

    International Nuclear Information System (INIS)

    Damle, Nishikant Avinash; Kumar, Rakesh; Kumar, Praveen; Jaganthan, Sriram; Patnecha, Manish; Bal, Chandrasekhar; Bandopadhyaya, Gurupad; Malhotra, Arun

    2011-01-01

    Skull base osteomyelitis is a potentially fatal disease. We demonstrate here the utility of SPECT/CT in diagnosing this entity, which was not obvious on a planar bone scan. A 99mT c MDP bone scan with SPECT/CT was carried out on a patient with clinically suspected skull base osteomyelitis. Findings were correlated with contrast enhanced CT (CECT) and MRI. Planar images were equivocal, but SPECT/CT showed intense uptake in the body of sphenoid and petrous temporal bone as well as the atlas corresponding to irregular bone destruction on CT and MRI. These findings indicate that SPECT/CT may have an additional role beyond planar imaging in the detection of skull base osteomyelitis.

  18. Ossicular erosions in the dry ear: CT diagnosis

    International Nuclear Information System (INIS)

    Swartz, J.D.; Nunnelly, D.E.; Zwillenberg, S.; Berger, A.S.; Popky, G.L.

    1986-01-01

    Erosions of the ossicular chain can occur as a complication of noncholesteatomatous chronic otitis media. These defects may appear on CT of the healed ''dry'' ear. Ischemic necrosis is the most likely etiology; however, acid phosphatase-containing lysosomes are also implicated. The incus (particularly the long and lenticular processes) is by far the most vulnerable ossicle. Coronal CT is especially valuable in diagnosing these erosions. Fibrous replacement of the incudostapedial articulation may be diagnosed on CT when an unusually wide ''joint'' is seen on axial CT scans

  19. CT diagnosis of optic nerve lesions in children

    International Nuclear Information System (INIS)

    Havlova, M.; Kvicala, V.; Nevsimalova, S.; Otradovec, J.

    1985-01-01

    Computer tomography (CT) was used to examine 17 children with lesions of the optic nerve. The procedure is described of the examination of the orbit and the sellar area. CT gave a very good image of expansive processes in both areas and of associated lesions of the CNS insofar as they were based on anatomical or pathological changes. (author)

  20. The check sheet for diagnosis of postmortem CT. Development and the first impression

    International Nuclear Information System (INIS)

    Takahashi, Naoya; Higuchi, Takeshi; Shiotani, Motoi; Sato, Suguru; Maeda, Haruo; Hirose, Yasuo

    2010-01-01

    We developed the check sheet for diagnosis of postmortem CT. We listed the findings that had been reported as causes of death, postmortem changes, and changes caused by cardiopulmonary resuscitation on the sheet. We used the check sheet for 26 postmortem CT of cases with cardiopulmonary arrest on arrival. The causes of death were proposed in 11 cases. The check sheet was useful to diagnose postmortem CT. (author)

  1. FDG-PET/CT in the diagnosis of recurrent breast cancer

    International Nuclear Information System (INIS)

    Murakami, Ryusuke; Kumita, Shin-ichiro; Yoshida, Tamiko; Ishihara, Keiichi; Kiriyama, Tomonari; Hakozaki, Kenta; Yanagihara, Keiko; Lida, Shinya; Tsuchiya, Shin-ichi

    2012-01-01

    Background. An advantage of PET/CT has been demonstrated for diagnosis of several tumor entities. In patients with breast cancer, early diagnosis and accurate restaging of recurrence after surgery is important for selection of the most appropriate therapeutic strategy. Purpose. To evaluate the accuracy of integrated positron emission tomography and computed tomography (PET/CT) using 18F-fluorodeoxyglucose (FDG), for follow-up of patients with suspected recurrent breast cancer. Material and Methods. Forty-seven patients with suspected recurrent breast cancer underwent PET/CT. The PET and PET/CT images were interpreted without knowledge of the results of other diagnostic modalities, and compared with each other with reference to the final diagnosis. Results. Twenty-five (53%) patients suffered tumor recurrence. The overall sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of PET/CT were 96%, 91%, 92%, 95%, and 94%, respectively. In comparison with PET, PET/CT had a higher sensitivity and accuracy (96% vs. 80% and 94% vs. 81%, respectively). The difference in diagnostic accuracy between PET/CT and PET was significant (P < 0.05). Conclusion. The present findings indicate that PET/CT is an accurate, sensitive and reliable modality for screening and detection of breast cancer recurrence. PET/CT appears to be an effective surveillance tool, as it is able to cover the whole body in a single procedure and shows good performance

  2. Contrast-enhanced dedicated breast CT detection of invasive breast cancer preceding mammographic diagnosis

    Directory of Open Access Journals (Sweden)

    Nicolas D. Prionas, MD, PhD

    2015-01-01

    Full Text Available Dedicated breast computed tomography (bCT generates high-resolution, three-dimensional images of the pendent uncompressed breast. Intravenous iodinated contrast during bCT provides additional physiologic information. In this case, a 10.0-mm invasive ductal carcinoma was visualized using contrast-enhanced breast CT one year before mammographic detection. Mammography four months before bCT was negative. The bCT contrast enhancement pattern closely matched the dynamic contrast-enhanced MRI obtained after diagnosis. Lesion enhancement at contrast-enhanced breast CT matched previously published enhancement values of breast cancer. Contrast-enhanced dedicated bCT provided high-resolution tomographic images and physiologic contrast enhancement data that facilitated the detection of an early breast cancer.

  3. Usefulness of computed tomography (CT) in the diagnosis of portosystemic collaterals in liver cirrhosis

    International Nuclear Information System (INIS)

    Tsukune, Yoshihiko

    1984-01-01

    This study assesses the usefulness of computed tomography (CT) in the diagnosis of portosystemic collaterals in liver cirrhosis. Seventy-eight patients with liver cirrhosis underwent both CT and angiography. Comparison was made between CT and angiography on eleven types of collaterals, and many of them were demonstrated on CT scans better than angio. Especially, esophageal varices, paraesophageal varices, umbilical pathway and caput medusa were diagnostic on CT scans. Gastrorenal collaterals, splenorenal collaterals, retroperitoneal pathway are also well demonstrated. Dilatation of azygos systems and small veins in the liver surface are only observed on CT scans. However, coronary varices and short gastric varices are well diagnostic in angiography. But considering all types of collaterals, it was stressed that angiography can be eliminated by CT in evaluation of collaterals in liver cirrhosis. (author)

  4. Results of diagnosis of pancreatic cancer by computed tomography (CT)

    International Nuclear Information System (INIS)

    Kimura, Kazue; Okuaki, Koji; Ito, Masami; Katakura, Toshihiko; Suzuki, Kenji

    1981-01-01

    Results of examination of pancreatic diseases, especially pancreatic cancer, conducted by CT during the past 3 years are summarized. The EMI CT Type 5000 or 5005 were used. During the 3 years from September 1976 to August 1979, a total of 1961 patients were examined by CT, and the upper abdomen was examined in 772 of these patients. In 97 patients, positive findings were obtained in the CT image of the pancreas. In 52 of these patients, the findings were confirmed operatively or by autopsy. Though cancer of the pancreas was diagnosed by CT in 30 patients, it was confirmed in 20 by surgical operation and in 1 by autopsy. Of the 9 misdiagnosed cases, 4 were cases of infiltration of the pancreas by carcinoma of the stomach or bile duct, and the other 5 were one case each of lipoma of the abdominal wall, normal pancreas, hyperplasia of Langerhans's islets of the pancreas tail, abscess between the pancreas and the posterior wall of the stomach, and choledocholithiasis. A case diagnosed by CT as cholelithiasis was a carcinoma measuring 5 x 5 x 6 cm located on the head of the pancreas, complicated by choledocholithiasis. The 22 patients with carcinoma of the pancreas were 9 with lesions less than 3.5 x 3.0 x 3.0 cm in size who could be radically operated, 6 who underwent exploratory laparotomy or autopsy, and 7 in whom operation was impossible. False negative and false positive CT results are also discussed. (author)

  5. Cholesterol granuloma of the petrous apex: CT diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Lo, W.W.M.; Solti-Bohman, L.G.; Brackmann, D.E.; Gruskin, P.

    1984-12-01

    Cholesterol granuloma of the petrous apex is a readily recognizable and treatable entity that is more common than previously realized. Cholesterol granuloma grows slowly in the petrous apex as a mass lesion until it produces hearing loss, tinnitus, vertigo, and facial twitching. Twelve cases of cholesterol granuloma of the petrous apex are illustrated; ten of these analyzed in detail, especially with respect to CT findings. A sharply and smoothly marginated expansile lesion in the petrous apex, isodense with plain and nonenhancing on CT, is in all probability a cholesterol granuloma. Preoperative recognition by CT is important for planning proper treatment.

  6. Cholesterol granuloma of the petrous apex: CT diagnosis

    International Nuclear Information System (INIS)

    Lo, W.W.M.; Solti-Bohman, L.G.; Brackmann, D.E.; Gruskin, P.

    1984-01-01

    Cholesterol granuloma of the petrous apex is a readily recognizable and treatable entity that is more common than previously realized. Cholesterol granuloma grows slowly in the petrous apex as a mass lesion until it produces hearing loss, tinnitus, vertigo, and facial twitching. Twelve cases of cholesterol granuloma of the petrous apex are illustrated; ten of these analyzed in detail, especially with respect to CT findings. A sharply and smoothly marginated expansile lesion in the petrous apex, isodense with plain and nonenhancing on CT, is in all probability a cholesterol granuloma. Preoperative recognition by CT is important for planning proper treatment

  7. Low dose CT in early lung cancer diagnosis: prevalence data

    International Nuclear Information System (INIS)

    Cardinale, Luciano; Cortese, Giancarlo; Ferraris, Fabrizio; Perotto, Fabio; Fava, Cesare; Borasio, Piero; Dogliotti, Luigi; Novello, Silvia; Scagliotti, Giorgio

    2005-01-01

    Purpose. Lung cancer has a high mortality rate and its prognosis largely depends on early detection. We report the prevalence data of the study on early detection of lung cancer with low-dose spiral CT underway at our hospital. Materials and methods. Since the beginning of 2001, 519 asymptomatic volunteers have undergone annual blood tests, sputum tests, urinalyses and low-dose spiral CT. The inclusion criteria were age (55 years old), a history of cigarette smoking and a negative history for previous neoplastic disease. The diagnostic workup varied depending on the size and CT features of the nodules detected. Results. At baseline, the CT scan detected nodules> 5 mm in 22% of subjects; the nodules were single in 42 and multiple in 71. In 53% of cases the findings were completely negative, while in 122 (23.4%) nodules with a diameter [it

  8. CT diagnosis of concealed rupture of intestine following abdominal trauma

    International Nuclear Information System (INIS)

    Ji Jiansong; Wei Tiemin; Wang Zufei; Zhao Zhongwei; Tu Jianfei; Fan Xiaoxi; Xu Min

    2009-01-01

    Objective: To investigate CT findings of concealed rupture of intestine following abdominal trauma. Methods: CT findings of 11 cases with concealed rupture of intestine following abdominal trauma proved by surgery were identified retrospectively. Results: The main special signs included: (1) Free air in 4 cases, mainly around injured small bowel or under the diaphragm, or in the retroperitoneal space or and in the lump. (2) High density hematoma between the intestines or in the bowel wall (4 cases). (3) Bowel wall injury sign, demonstrated as low density of the injured intestinal wall, attenuated locally but relatively enhanced in neighbor wall on enhanced CT. (4) Lump around the injured bowel wall with obvious ring-shaped enhancement (4 cases). Other signs included: (1) Free fluid in the abdominal cavity or between the intestines with blurred borders. (2) Bowel obstruction. Conclusion: CT is valuable in diagnosing concealed rupture of intestine following abdominal trauma. (authors)

  9. Usefulness of MRI compared with CT for diagnosis of mesenteric lymphoma in a dog

    International Nuclear Information System (INIS)

    Yasuda, D.; Fujita, M.; Yasuda, S.; Taniguchi, A.; Miura, H.; Hasegawa, D.; Orima, H.

    2004-01-01

    We evaluated the usefulness of MRI and compared it with CT for diagnosis of mesenceric lymphoma in a dog. The results in the plain CT. dynamic CT and plain MR (TIWI and t2W1) images suggested that the mass was a large single nodular lesion with abundant blood perfusion. On enhanced MRI(T1WI) , the mass was depicted as a tumor with adhesion to the gut wall, Exploratory laparotomy confirmed the mass was consistent with the findings on enhanced MRI. We think that MRI might be a useful imaging tool for diagnosis of canine mesenteric lymphoma

  10. Usefulness of MRI compared with CT for diagnosis of mesenteric lymphoma in a dog.

    Science.gov (United States)

    Yasuda, Daiji; Fujita, Michio; Yasuda, Shuichi; Taniguchi, Akiko; Miura, Harumi; Hasegawa, Daisuke; Orima, Hiromitsu

    2004-11-01

    We evaluated the usefulness of MRI and compared it with CT for diagnosis of mesenteric lymphoma in a dog. The results in the plain CT, dynamic CT and plain MR (T1WI and T2WI) images suggested that the mass was a large single nodular lesion with abundant blood perfusion. On enhanced MRI(T1WI) , the mass was depicted as a tumor with adhesion to the gut wall. Exploratory laparotomy confirmed the mass was consistent with the findings on enhanced MRI. We think that MRI might be a useful imaging tool for diagnosis of canine mesenteric lymphoma.

  11. CT and MRI diagnosis of traumatic basal ganglia hemorrhage

    International Nuclear Information System (INIS)

    Wu Shike; Zhang Yalin; Xu Derong; Zou Gaowei; Chen Dan; He Sujun; Zhou Lichao

    2009-01-01

    Objective: To analyze CT and MRI features of traumatic basal ganglia hemorrhage and investigate the diagnostic value. Methods: 21 cases with traumatic basal ganglia hemorrhage diagnosed by clinic, CT and MRI in our hospital were collected in this study Plain CT scan were immediately performed in 21 cases after injury, plain MR scan were performed in 1 to 3 days. 12 cases of them underwent diffusion weighted imagine (DWI). The CT and MRI findings were retrospectively summarized. Results: 8 cases were found with simple traumatic basal ganglia hemorrhage. Complexity of basal ganglia hemorrhage occurred in 13 cases, 6 cases combined with subdural hemorrhage, 3 cases with epidural hematoma, 2 cases with subarachnoid hemorrhage, 6 cases with brain contusion and laceration in other locations, 4 cases with skull fracture. 26 lesions of basal ganglia hematoma were showed in 21 cases, 14 lesions of pallidum hemorrhage in 11 cases confirmed by MR could not be distinguished from calcification at the fast CT scan. 5 more lesions of brain contusion and laceration and 4 more lesions of brain white matter laceration were found by MR. Conclusion: CT in combination with MRI can diagnose traumatic basal ganglia hemorrhage and its complications early, comprehensively and accurately, which plays an important role in the clinical therapy selection and prognosis evaluation. (authors)

  12. CT diagnosis in the evaluation of vertebral trauma

    International Nuclear Information System (INIS)

    Emori, Takumi; Kadoya, Satoru; Nakamura, Tsutomu; Ito, Shotaro; Kwak, Ryungchan

    1984-01-01

    The diagnostic capability of the CT scan of the vertebral trauma and a comparison with the results of a routine roentgenogram and tomogram were studied in 11 patients. In total, there were 15 fractured vertebrae: 3 in the upper cervical, 3 in the lower cervical, and 9 in the thoracic and thoraco-lumbar vertebrae. In the detailed evaluation of the vertebral fractures, CT provided more information than plain films in all 15 fractured vertebrae, with a better visualization of the spinal bony details, particularly at the upper cervical, thoracic, and thoraco-lumbar levels, where the interpretation of the spinal abnormalities is usually difficult because of adjacent structures such as the skull and thorax. Only CT was able to demonstrate impingements on the vertebral canal by bony fragments. Post-traumatic syringomyelia was incidentally demonstrated in one patient on a plain CT. In 6 patients, conventional tomography was done, but no additional information with regard to spinal instability and spinal-cord compression was obtained. The usage of sagittal tomography was also limited, because it required a change in the patient's position, which might worsen the neurological deficits. On the other hand, a plain roentgenogram and conventional tomography were superior in the evaluation of spinal malalignment and fractures running horizontally. In summary, both plain roentgenograms and CT images provided detailed information about vertebral injury, whereas conventional tomography is judged to be inferior and not always necessary. Based on these results, our new diagnostic and therapeutic approaches using CT for the vertebral injuries were presented. (author)

  13. Clinical value of SPECT/CT imaging in the diagnosis of bone metastasis

    International Nuclear Information System (INIS)

    Wang Xinhua; Zhao Yanping; Lu Haijian; Dong Zhanfei

    2010-01-01

    Objective: To evaluate the clinical value of 99 Tc m -methylene diphosphonic acid (MDP) SPECT/CT imaging for the diagnosis of bone metastasis. Methods: Patients suspected for bone metastasis and with bone pain of unknown origin were included in this study (n=237). All cases underwent SPECT and CT imaging at 180 min after 99 Tc m -MDP injection. Diagnosis was confirmed by pathology (n=21), more than 2 kinds of radiologieal imaging (MRI, CT, X-ray) (n=106), and clinical follow up in 2 years (n=110). χ 2 -test was used to compare the results of planar and SPECT/CT imaging using SAS 6.12 software. Results: In 237 patients, planar imaging of 142 cases matched the final diagnosis in which 72 had benign lesions and 70 had bone metastases. The definite coincidence rate was 95.30% (142/149). SPECT/CT imaging of 224 cases matched the final diagnosis in which 104 had benign lesions and 120 cases diagnosed as bone metastases. The coincidence and definite coincidence rates were 94.51% (224/237), and 99.48% (192/193). Difference in the definite coincidence rate between planar and SPECT/CT imaging was statistically significant (χ 2 = 5.37, P=0.024). Conclusion: SPECT/CT imaging is valuable for accurate localization of osseous pathology and for improvement of diagnosing bone metastasis. (authors)

  14. Diagnosis of tracheal instability: inspiratory and expiratory spiral CT and cine CT

    International Nuclear Information System (INIS)

    Heussel, C.P.; Thelen, M.; Kauczor, H.U.; Hafner, B.; Lill, J.

    2000-01-01

    Purpose: In tracheo- and bronchomalacia, localization and determination of collapse is necessary for planning a surgical procedure. We compared inspiratory and spiral CT, cine CT, and bronchoscopy and evaluated the relevance of each method. Methods: Seventeen patients with suspected or verified tracheal stonosis or collapse underwent paired inspiratory and exspiratory spiral CT and cine CT during continuous respiration (temporal increment 100 ms). The tracheal cross-sectional area was calculated and compared. Results: In addition to bronchoscopy, further information concerning localization, extent, collapse, stability of the tracheal wall, distal portions of the stenosis, and extraluminal compressions was obtained. A significantly higher degree of tracheal collapse was seen using cine CT compared to paired spiral CT (p [de

  15. An application of dynamic CT for diagnosis of abnormal external ocular muscle movement

    International Nuclear Information System (INIS)

    Tomita, Kazumi; Ogura, Yuuko; Takeshita, Gen; Koga, Sukehiko; Katada, Kazuhiro; Anno, Hirofumi.

    1993-01-01

    To evaluate the movements of retrobulbar structures radiologically, we have developed a new technique called 'external ocular muscle movement CT' (EOM CT), in which dynamic CT scanning is performed while the patient performs controlled eye movements. This new technique was applied in one volunteer and 72 patients with external ophthalmoplegia due to orbital mass lesion, hyperthyroid ophthalmopathy, blowout fracture, and other retrobulbar lesions. EOM CT permits the assessment of extraocular muscle contraction in cases of blowout fracture, the evaluation of muscular contraction in hypertrophy of the extraocular muscles, and the diagnosis of adhesions between the extraocular muscles and intraorbital masses. Radiation dose to the lens from EOM CT was measured using a phantom and TLD, and was compared with that of conventional CT scanning with a 5 mm slice thickness. The dose to the lens from EOM CT was three times higher than that for conventional CT in axial scanning, but in the coronal section of the retrobulbar region, the dose to the lens from EOM CT decreases to one twelfth of that of conventional CT. EOM CT promises to be a powerful modality for functional evaluation of the extraocular muscles and other retrobulbar structures. (author)

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

    International Nuclear Information System (INIS)

    Nakatani, Seiki

    1998-01-01

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

  17. Multislice CT of the auditory ossicles and ossicular ligaments. Delineation of normal anatomy and diagnosis of congenital anomaly

    International Nuclear Information System (INIS)

    Matsumoto, Shigeru; Tozaki, Hiromitu; Miyazaki, Hidemi

    2001-01-01

    By using four detector rows with 0.5 mm collimation, high resolution isotropic voxel data throughout the middle ear can be obtained with Multislice Helical CT (MSCT). The purpose of this study is to evaluate the usefulness of MSCT in demonstrating the auditory ossicles and ossicular ligaments and in the diagnosis of congenital ossicular anomalies. Thirty normal middle ears and 23 ear of 20 patients with suspicious congenital ossicular anomalies were examined. Axial images and multiplanar images were reconstructed. In the normal group, the images were evaluated based on scores for the visualization of the anatomical structure of the auditory ossicles and ossicular ligaments. In the group with anomalies, the findings suggesting ossicular anomalies were referenced and the prevalence was conjectured. Visualization of the auditory ossicles and ossicular ligaments was 98.3%-100% and 78.3%-100%, respectively. Congenital ossicular anomalies were detected in 20 ears (87.0%). MSCT is an accurate method for demonstrating minute and complicated 3D structures of the middle ear, and is found to be a technique of choice for diagnosis of ossicular anomalies. (author)

  18. CT diagnosis of appendicitis. Usefulness for staging of the disease

    International Nuclear Information System (INIS)

    Abe, Yoshitaka; Shimizu, Tadafumi; Sugimura, Kazurou

    2002-01-01

    The main purpose of this study is to determine signs and indexes useful for differentiating grades of appendicitis (catarrhal, phlegmonous, gangrenous). We assessed CT findings of 98 cases of appendicitis retrospectively. Nonenhanced CT scans were obtained in 83 cases and enhanced scans in 15 cases. No patients were given oral or colon contrast media. Each examination was performed from the level of the diaphragm to the pubic symphysis with 10 mm or 7 mm slice thickness and intervals. All images were examined for CT signs of appendicitis and the diameter and appearance of the appendix. We statistically analyzed the results and white blood cell count. We detected an abnormal appendix in 88 cases. Two CT signs identified and their sensitivity, specificity, and accuracy, respectively, included fat stranding around the appendix (92.2%, 81.8%, 90.9%) and indistinct wall of the appendix (63.9%, 94.2%, 81.8%). The diameter of the appendix differed significantly among the three grades (p=0.0008). The appearance of the appendix could be divided into 5 types, which exhibited correlation with the grades, although white blood cell count did not (p=0.1988). Fat stranding and indistinct wall, and appendix diameter and CT appearances provided useful signs and indexes for staging of appendicitis. (author)

  19. CT of jejunal diverticulitis: imaging findings, differential diagnosis, and clinical management

    International Nuclear Information System (INIS)

    Macari, M.; Faust, M.; Liang, H.; Pachter, H.L.

    2007-01-01

    Aim: To describe the imaging findings of jejunal diverticulitis as depicted at contrast-enhanced computed tomography (CT) and review the differential diagnosis and clinical management. Materials and Methods: CT and pathology databases were searched for the diagnosis of jejunal diverticulitis. Three cases were identified and the imaging and clinical findings correlated. Results: Jejunal diverticulitis presents as a focal inflammatory mass involving the proximal small bowel. A trial of medical management with antibiotics may be attempted. Surgical resection may be required if medical management is unsuccessful. Conclusion: The imaging findings at MDCT may allow a specific diagnosis of jejunal diverticulitis to be considered and may affect the clinical management of the patient

  20. A comparative study of digital GI and CT in diagnosis of gastric carcinoma

    International Nuclear Information System (INIS)

    Wan Xiangrong; Chen Guoqin; Ding Xinmin

    2003-01-01

    Objective: To evaluate the digital GI and CT in the diagnosis of gastric carcinoma. Methods: Total 42 patients with gastric carcinoma received digital GI and CT examination. The digital GI and CT findings were analyzed comparatively. Results: 42 cases of patients with gastric carcinoma were examined with digital GI and CT. Digital GI demonstrated mucosal erosion in 40 cases, narrowed gastric lumen in 12, malignant ulceration in 10, filling defect in 12 and abnormal peristalsis in 36. CT revealed gastric wall thickening in 30 cases, intra-gastric masses in 36, narrowed gastric lumen in 36, regional lymphadenopathy and/or distant metastases in 19 and pyloristenosis in 4. Conclusion: The lesions in stomach could be demonstrated on digital GI, the imaging is clear and precise. CT is valuable for assessing the extra-gastric involvement, lymphadenopathy and distant metastases, which is an important pre-operative examination

  1. Clinical significance of CT in the preoperative diagnosis of the staging of rectal cancer patients

    International Nuclear Information System (INIS)

    Itano, Satoshi; Fuchimoto, Sadanori; Hamada, Fumihiro; Kimura, Takanobu; Iwagaki, Hiromi; Maeda, Tetsuya; Orita, Kunzo

    1987-01-01

    The value of computed tomography (CT) in the preoperative clinical staging of rectal cancer was prospectively studied in 28 patients with macroscopically proven cancer. The CT studies were based on the previously established CT diagnostic criteria for wall invasion (S factor), lymph node metastases (N factor), and liver metastases (H factor). When macroscopic findings were used as the standard, the accuracy of CT was 61 % for S factor, 32 % for N factor, and 86 % for H factor. Using histological findings as the standard, the accuracy was 48 % for S factor and 16 % for N factor. Overall, CT had a high accuracy for H factor in all sites of cancer (75 % in the rectosigmoid, 86 % in the area above the peritoneal reflection, and 90 % in the area below the peritoneal reflection). For the other S and N factors, CT seemed to be of limited value in the preoperative diagnosis. (Namekawa, K.)

  2. CT diagnosis of volvulus in children and adolescence intestinal malrotation

    International Nuclear Information System (INIS)

    Cheng Jianmin; Zheng Xiangwu; Yu Zhikang; Wu Enfu; Wu Aiqin; Xu Fanghong

    2001-01-01

    Objective: To study the CT manifestations of volvulus in intestinal malrotation (VIM) so as to recognize the characteristics of VIM. Methods: Six cases of VIM proved by surgery were reviewed, there were 5 males and 1 female, and the mean age was 13 years. Results: A characteristic CT appearance consisting of multiple dilated intestinal loops with edematous mesenteric folds was found. Mesenteric vessels converging toward the root of superior mesenteric artery ('whirl sign') was demonstrated in 4 cases. The 'target sign', which also showed 'whirl sign' after enhancement was found in 2 cases. Marked venous obstruction with thickening of the involved intestinal segment bowel wall was present in 2 cases. Conclusion: The predominant 'whirl sign' with the abnormal arrangement of superior mesenteric artery and veins at the mesenteric root was a characteristic CT finding of VIM

  3. Contribution of brain CT in the diagnosis of tuberculous meningitis: a case report from Djibouti.

    Science.gov (United States)

    Garetier, M; Roche, N C; Longin, C; Clapson, P; Benois, A; Rousset, J

    2017-08-01

    Tuberculous meningitis, a serious disease with high mortality and morbidity, remains frequent in countries with endemic tuberculosis. Its non-specific presentation often delays the introduction of appropriate treatment. Its definitive diagnosis requires isolation of Mycobacterium tuberculosis from cerebrospinal fluid, although this test may be negative without conclusively ruling out this diagnosis. A presumptive diagnosis should be reached as soon as possible through a body of clinical evidence, including the lumbar puncture findings. Brain computed tomography (CT) with and without contrast medium injection is helpful for the diagnosis of tuberculous meningitis and its complications. We discuss the features of CT and their value in relation to a case of tuberculous meningitis in Djibouti, as well as the role of CT in managing this disease.

  4. CT diagnosis of abdominal lymph node metastases in hepatocellular carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T; Nakamura, H; Choi, S; Morimoto, K; Kawamoto, S; Hori, S; Tokunaga, K; Yoskioka, H; Kuroda, C

    1985-08-01

    CT scanning is useful for diagnosing abdominal lymph node metastasis. Using this technique, histologically confirmed abdominal lymph node metastases were detected in nine of 49 patients (33 autopsy cases and 16 laparotomy cases) with hepatocellular carcinoma (hepatoma). Among the 49 patients, three had periportal (6.1%), six peripancreatic (12.2.%) and six para-aortic adenopathies (12.2%). Two of the patients had adenopathy at all three sites. Retrospectively, CT detected two periportal, four peripancreatic and all six para-aortic adenopathies. Most of the hepatomas with adenopathy showed infiltrative growth; tumour thrombosis of the portal vein was a common complication.

  5. The diagnosis of renal perfusion abnormalities by sequential CT

    International Nuclear Information System (INIS)

    Treugut, H.; Andersson, I.; Hildell, J.; Nyman, U.; Weibull, H.

    1981-01-01

    Abnormalities of renal perfusion can be recognised more readily by sequential CT than by plain CT scan or after static enhancement with contrast medium. Haemodynamically significant stenoses of the renal arteries and total, or partial, infarcts can be diagnosed in this way. Intrarenal and capsular collaterals can be recognised by slow contrast accumulation in the infarcted area, or by the development of contrast in the sub-capsular portion of the cortex. Renal cortical necrosis is very well demonstrated by the absence of cortical perfusion; this is seen, for instance, in the DIC syndrome or during rejection after renal transplant. (orig.) [de

  6. Diagnosis of renal perfusion abnormalities by sequential CT

    Energy Technology Data Exchange (ETDEWEB)

    Treugut, H; Andersson, I; Hildell, J; Nyman, U; Weibull, H

    1981-10-01

    Abnormalities of renal perfusion can be recognised more readily by sequential CT than by plain CT scan or after static enhancement with contrast medium. Haemodynamically significant stenoses of the renal arteries and total, or partial, infarcts can be diagnosed in this way. Intrarenal and capsular collaterals can be recognised by slow contrast accumulation in the infarcted area, or by the development of contrast in the sub-capsular portion of the cortex. Renal cortical necrosis is very well demonstrated by the absence of cortical perfusion; this is seen, for instance, in the DIC syndrome or during rejection after renal transplant.

  7. Exploration of cervical carotid stenosis using helical CT angiography. A prospective trial on the detection of candidates for surgery in the Gujo area, Gifu

    Energy Technology Data Exchange (ETDEWEB)

    Yamakawa, Hiroyasu; Sumi, Yasuhiko [Sumi Hospital, Gifu (Japan); Kaku, Yasuhiko; Sakai, Noboru; Yamada, Hiromu

    1995-04-01

    To detect cervical carotid stenosis as a candidate for carotid endarterectomy (CEA), the authors attempted a prospective trial by exploring stenosis for one year in a rural district with a population of 20,000, employing helical CT angiography which apparently displayed three-dimensional reconstructed images of the carotid bifurcation. Thirty-three patients, 24 males and 9 females, with a mean age of 71.8 years, suffering from TIA, RIND or stroke were investigated for their carotid systems. The clinical symptoms of the patients were briefly as follows: motor weakness in 30 cases, dysarthria in 8 cases and aphasia in 4 cases; and 6 of 22 (27%) stroke cases had previously suffered an episode of TIA. The risk factors of the whole group of patients were hypertension in 13 cases, diabetes mellitus in 6, heart disease in 17, and hypercholesteremia in 4. Helical CT angiography was performed in 11 cases of TIA, 2 cases of RIND, and 16 cases of stroke. Only 3 cases of the TIA group and 3 cases of the stroke group were found to have extracranial carotid stenosis of more than 50%, which subsequently required conventional angiography. For the detection of stenosis, CT angiography was beneficial as well as conventional angiography. Finally, CEA was performed in 2 of 3 cases with severe carotid stonosis in the TIA group, while such cases in the stroke group were only observed. The above results meant that the occurrence of extracranial carotid stenosis was 6 out of 6,589 elderly inhabitants (over 60 years old), although the possible detection rate of candidates for CEA was 2 out of 20,000 population per year. (author).

  8. Exploration of cervical carotid stenosis using helical CT angiography. A prospective trial on the detection of candidates for surgery in the Gujo area, Gifu

    International Nuclear Information System (INIS)

    Yamakawa, Hiroyasu; Sumi, Yasuhiko; Kaku, Yasuhiko; Sakai, Noboru; Yamada, Hiromu.

    1995-01-01

    To detect cervical carotid stenosis as a candidate for carotid endarterectomy (CEA), the authors attempted a prospective trial by exploring stenosis for one year in a rural district with a population of 20,000, employing helical CT angiography which apparently displayed three-dimensional reconstructed images of the carotid bifurcation. Thirty-three patients, 24 males and 9 females, with a mean age of 71.8 years, suffering from TIA, RIND or stroke were investigated for their carotid systems. The clinical symptoms of the patients were briefly as follows: motor weakness in 30 cases, dysarthria in 8 cases and aphasia in 4 cases; and 6 of 22 (27%) stroke cases had previously suffered an episode of TIA. The risk factors of the whole group of patients were hypertension in 13 cases, diabetes mellitus in 6, heart disease in 17, and hypercholesteremia in 4. Helical CT angiography was performed in 11 cases of TIA, 2 cases of RIND, and 16 cases of stroke. Only 3 cases of the TIA group and 3 cases of the stroke group were found to have extracranial carotid stenosis of more than 50%, which subsequently required conventional angiography. For the detection of stenosis, CT angiography was beneficial as well as conventional angiography. Finally, CEA was performed in 2 of 3 cases with severe carotid stonosis in the TIA group, while such cases in the stroke group were only observed. The above results meant that the occurrence of extracranial carotid stenosis was 6 out of 6,589 elderly inhabitants (over 60 years old), although the possible detection rate of candidates for CEA was 2 out of 20,000 population per year. (author)

  9. Small bowel obstruction in children: usefulness of CT for diagnosis and localization

    International Nuclear Information System (INIS)

    Lee, Young Cheol; Kim, Young Tong; Bae, Won Kyung; Kim, Il Young

    2007-01-01

    To evaluate the usefulness of CT for the diagnosis of the cause and localization of small bowel obstruction. Out of a group of children who underwent a CT examination for a suspected small bowel obstruction, 19 patients with confirmed underlying disorders were identified and included in the study. Neonates and patients with duodenal obstruction were excluded from the study. The CT findings were analyzed for the location of obstruction site, abnormalities of the mesentery and mesenteric vessels, bowel wall thickening, closed loop obstruction, and strangulation. The obstruction site was divided into five parts. The preoperative CT diagnosis was compared with the final diagnosis. Causes of small bowel obstruction were intussusception (n = 6), appendiceal perforation (n = 4), transmesenteric internal hernia (n = 2), postoperative bands (n = 1), idiopathic multiple bands (n = 1), a foreign body (n = 1), a small bowel adenocarcinoma (n = 1), Meckel's diverticulitis (n = 1), tuberculous peritonitis (n = 1) and Salmonella enteritis with bowel perforation (n = 1). The CT findings showed mesenteric vascular prominence (n = 13), omental or mesenteric infiltration (n = 10), localized bowel wall thickening (n = 7) closed loops obstruction (n = 3) and strangulation (n = 1). The obstruction site was identified in all cases. The causes of obstruction could be diagnosed preoperatively in 14 cases, but a preoperative diagnosis was difficult in 5 cases. The causes of small bowel obstruction in children are variable, and CT is useful for evaluating the cause and localization of small bowel obstruction

  10. Small bowel obstruction in children: usefulness of CT for diagnosis and localization

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Young Cheol; Kim, Young Tong; Bae, Won Kyung; Kim, Il Young [Cheonan Hospital, Soonchunhyang University, Cheonan (Korea, Republic of)

    2007-12-15

    To evaluate the usefulness of CT for the diagnosis of the cause and localization of small bowel obstruction. Out of a group of children who underwent a CT examination for a suspected small bowel obstruction, 19 patients with confirmed underlying disorders were identified and included in the study. Neonates and patients with duodenal obstruction were excluded from the study. The CT findings were analyzed for the location of obstruction site, abnormalities of the mesentery and mesenteric vessels, bowel wall thickening, closed loop obstruction, and strangulation. The obstruction site was divided into five parts. The preoperative CT diagnosis was compared with the final diagnosis. Causes of small bowel obstruction were intussusception (n = 6), appendiceal perforation (n = 4), transmesenteric internal hernia (n = 2), postoperative bands (n = 1), idiopathic multiple bands (n = 1), a foreign body (n = 1), a small bowel adenocarcinoma (n = 1), Meckel's diverticulitis (n = 1), tuberculous peritonitis (n = 1) and Salmonella enteritis with bowel perforation (n = 1). The CT findings showed mesenteric vascular prominence (n = 13), omental or mesenteric infiltration (n = 10), localized bowel wall thickening (n = 7) closed loops obstruction (n = 3) and strangulation (n = 1). The obstruction site was identified in all cases. The causes of obstruction could be diagnosed preoperatively in 14 cases, but a preoperative diagnosis was difficult in 5 cases. The causes of small bowel obstruction in children are variable, and CT is useful for evaluating the cause and localization of small bowel obstruction.

  11. CT diagnosis of gluteal muscle contracture in children

    International Nuclear Information System (INIS)

    Wang Longsheng; Bao Jiaqi; Pan Zhili; Hu Kefei; Jiang Jiatan; Zhang Hongliang; Sun Jun; Yuan Yi

    2004-01-01

    Objective: To investigate the CT manifestations of gluteal muscle contracture (GMC) in children. Methods: Sixty-one cases of GMC diagnosed by CT and proved by surgery and pathology were studied with 20 cases of non-GMC as the control group. Results: 57 cases (93.4%) were bilateral contracture and 4 cases (6.6%) were unilateral contracture in 61 cases of GMC; The main CT manifestations were as follows: (1) gluteal muscle volume shrunk. There were 118 (100.0%) sides of gluteus maximus contracture , 16 ( 13.6 %) sides of gluteus medius contracture , 12 ( 10.2 %) sides of piriformis contracture, 4 (3.4%) sides of gluteus minimus contracture, 4 (3.4%) sides of capsula articularis contracture; (2) calcification and necrosis in injection zones. There were 95 (80.5%) sides of gluteal calcification and 24 (20.3%) sides of gluteal necrosis; (3) stripe crispation fascia. There were 81 stripes crispation fascia located outboard laterals of gluteus maximus, 36 located inboard laterals of the latter; (4) gluteal muscle clearance widened. There were 38 (32.2%) sides of light degree gluteal muscle contracture, 53 (44.9%) sides of middle degree, and 27 (22.9%) sides of heavy degree. Conclusion: CT can accurately diagnose GMC and it plays an important role in the evaluation of pathological extent and degree of GMC

  12. SPECT/CT Fusion in the Diagnosis of Hyperparathyroidism

    International Nuclear Information System (INIS)

    Monzen, Yoshio; Tamura, Akihisa; Okazaki, Hajime; Kurose, Taichi; Kobayashi, Masayuki; Kuraoka, Masatsugu

    2015-01-01

    In this study, we aimed to analyze the relationship between the diagnostic ability of fused single photon emission computed tomography/ computed tomography (SPECT/CT) images in localization of parathyroid lesions and the size of adenomas or hyperplastic glands. Five patients with primary hyperparathyroidism (PHPT) and 4 patients with secondary hyperparathyroidism (SHPT) were imaged 15 and 120 minutes after the intravenous injection of technetium99m-methoxyisobutylisonitrile ( 99m Tc-MIBI). All patients underwent surgery and 5 parathyroid adenomas and 10 hyperplastic glands were detected. Pathologic findings were correlated with imaging results. The SPECT/CT fusion images were able to detect all parathyroid adenomas even with the greatest axial diameter of 0.6 cm. Planar scintigraphy and SPECT imaging could not detect parathyroid adenomas with an axial diameter of 1.0 to 1.2 cm. Four out of 10 (40%) hyperplastic parathyroid glands were diagnosed, using planar and SPECT imaging and 5 out of 10 (50%) hyperplastic parathyroid glands were localized, using SPECT/CT fusion images. SPECT/CT fusion imaging is a more useful tool for localization of parathyroid lesions, particularly parathyroid adenomas, in comparison with planar and or SPECT imaging

  13. Significance and problems of the dynamic CT scan for the diagnosis and treatment of cerebral infarctions

    International Nuclear Information System (INIS)

    Morita, Akio; Teraoka, Akira

    1985-01-01

    Dynamic CT scan is a very useful method for the diagnosis of cerebral infarctions and other ischemic disorders. We have used this method for 1) the ultra-early stage diagnosis of major infarctions, 2) the detection of the recanalization and the disruption of the blood-brain barrier, and 3) the detection of latent ischemic lesions. In this report we discussed the clinical cases and the usual use of this dynamic CT scan. We used a GE CT/T8800 scanner for dynamic CT scanning. Manual bolus-contrast-medium injection was done simultaneously with the first scanning, and 6 sequential scannings (scan time: 4.8 s; scan interval: 1.4 s) were done on the same slice level. Especially in major infarctions (e.g., MCA occlusion), OM 40 was the most preferred slice. In cases of ultra-early stage infarctions (i.e., no abnormal lesions in non-enhanced CT), we used this dynamic CT scan immediately after the non-enhanced CT; we could thus obtain information on the ischemic lesions and the ischemic degree. After that we repeated this examination on Days 3, 7, and 14 for the evaluation of the recanalization and blood-brain-barrier disruption. In the cases of TIA and impending or progressing strokes, dynamic CT scan could disclose latent ischemic lesions; in there instances, we treated the patients with intensive to prevent the prognosis from worsening. These benefits and also some problems were discussed. (author)

  14. CT diagnosis of brain tumor types with the aid of a new, CT-controlled stereotactical device

    International Nuclear Information System (INIS)

    Huk, W.

    1980-01-01

    The hitherto unparalleled information quality of computerized tomography elicited hopes that it might also be possible to differentiate cerebral tumors according to their histologic character and degree of malignity. The present work proposes to investigate whether CT information can be useful in the diagnosis of types of brain tumors. A first part contains a critical analysis of CT findings as to their specific information value and a comparison with the possibilities previously offered by neuroradiology. In a second part, and as a consequence of the investigations in Part I, a newly developed stereotactical procedure is described combining the capacity of CT for precise location with the accuracy of aim of a stereotactical device so that cerebral proliferations evading other diagnostical attempts can be histologically cleared up. (orig./MG) [de

  15. The value of spiral CT thin imaging reconstruction in the diagnosis of obstructive jaundice

    International Nuclear Information System (INIS)

    Huang Zhi; Liu Zhang; Yang Chaoxiang; Lin Chengye; Zhang Li; Li Yuxiang; Ma Yunyan; Xiao Haisong; Lu Zhifeng; Wang Bo; Zhou Yunhong

    2009-01-01

    Objective: To approach the value of spiral CT thin imaging reconstruction in the diagnosis of obstructive jaundice in order to improve the correctness of the diagnosis. Methods: Analysis the cases' clinical manifestation and the CT images, who were diagnosed as obstructive jaundice by operation. All of cases had high-resolution computed tomograyhy scan. The thickness and the interval is 5mm, reconstructed the thickness and the interval to 1 mm and 1.5 mm, then send the images to the workstation and MRR were processed. Analysis the date with the pathology. Results: Spiral CT thin imaging reconstruction have 98% and 93% in the accuracy of location and characterization in the obstruction. Conclusion: The spiral CT thin imaging reconstruction is a good method to improve the accuracy of location and characterization in the obstructive jaundice. (authors)

  16. Quantitative assessment for pneumoconiosis severity diagnosis using 3D CT images

    Science.gov (United States)

    Hino, Koki; Matsuhiro, Mikio; Suzuki, Hidenobu; Kawata, Yoshiki; Niki, Noboru; Kato, Katsuya; Kishimoto, Takumi; Ashizawa, Kazuto

    2018-02-01

    Pneumoconiosis is an occupational respiratory illness that occur by inhaling dust to the lungs. 240,000 participants are screened for diagnosis of pneumoconiosis every year in Japan. Radiograph is used for staging of severity rate in pneumoconiosis worldwide. CT imaging is useful for the differentiation of requirements for industrial accident approval because it can detect small lesions in comparison with radiograph. In this paper, we extracted lung nodules from 3D pneumoconiosis CT images by two manual processes and automatic process, and created a database of pneumoconiosis CT images. We used the database to analyze, compare, and evaluate visual diagnostic results of radiographs and quantitative assessment (number, size and volume) of lung nodules. This method was applied to twenty pneumoconiosis patients. Initial results showed that the proposed method can assess severity rate in pneumoconiosis quantitatively. This study demonstrates effectiveness on diagnosis and prognosis of pneumoconiosis in CT screening.

  17. Honeycombing on CT; its definition, pathologic correlation, and future direction of its diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Johkoh, Takeshi, E-mail: johkoht@aol.com [Department of Radiology, Kinki Central Hospital of Mutual Aid Association of Public School Teachers, 3-1 Kurumazuka, Itami, Hyogo, 664-8533 (Japan); Sakai, Fumikazu [Department of Diagnostic Radiology, Saitama International Medical Center, Saitama Medical University, Hidaka (Japan); Noma, Satoshi [Department of Radiology, Tenri Hospital, Tenri (Japan); Akira, Masanori [Department of Radiology, National Hospital Organization Kinki-Chuo Chest Medical Center, Sakai (Japan); Fujimoto, Kiminori [Department of Radiology and Center for Diagnostic Imaging, Kurume University School of Medicine, Kurume (Japan); Watadani, Takeyuki [Department of Radiology, University of Tokyo, Tokyo (Japan); Sugiyama, Yukihiko [Department of Internal Medicine, Jichi Medical University, Shimotsuke (Japan)

    2014-01-15

    Honeycombing on CT is the clue for the diagnosis of usual interstitial pneumonia (UIP) and its hallmark. According to the ATS-ERS-JRS-ALAT 2010 guideline, the patients with honeycombing on CT can be diagnosed as UIP without surgical biopsy. On CT scans, it is defined as clustered cystic airspaces, typically of comparable diameters of the order of 3–10 mm, which are usually subpleural and have well-defined walls. Pathologically, honeycombing consists of both collapsing of multiple fibrotic alveoli and dilation of alveolar duct and lumen Although the definition of honeycombing seems to be strict, recognition of honeycombing on CT is various among each observer Because typical honeycombing is frequently observed in the patients with UIP, we should judge clustered cysts as honeycombing when a diagnosis of UIP is suspected.

  18. The role of CT in the diagnosis of tumors in sellar area

    International Nuclear Information System (INIS)

    Li Wenxin

    2005-01-01

    Objective: To evaluate computed tomography (CT) in patients with tumors in sellar area. Methods: CT images of 33 patients with sellar area tumor's proved by surgery and pathology were analyzed retrospectively. Results: Pituitary adenomas (n=20), craniopharyngiomas (n=8) and meningiomas (n=3) had characteristic findings and were given a high rate of correct diagnosis. While astrocytoma (n=1) and germinoma (n=1) were solid lesions in sellar area and lack of diagnostic signs and the astrocytoma was misdiagnosed as craniopharyngioma. Conclusion: CT, especially 2-demision reconstructed (coronal and sagittal) images can demonstrate inner structure, pattern of growth, extension of invasion of tumors as well as the relationship between tumor and the adjacent vessels. CT plays an important role in the diagnosis of tumors in seliar area. (authors)

  19. Wunderlich's syndrome secondary to renal angiomyolipoma: CT diagnosis

    International Nuclear Information System (INIS)

    Sabate, J.M.; Gimenez, A.M.; Parellada, J.A.; Franquet, T.; Reig, C.

    1996-01-01

    We present three cases of renal angiomyolipoma with spontaneous perineal bleeding. The diagnosis was based on computerized tomography which disclosed the fatty component of the tumor and defined the retroperitoneal extension of the bleeding. (Author) 16 refs

  20. CT diagnosis of intramedulear lesions of the tubular bone

    International Nuclear Information System (INIS)

    Wagner-Manslau, C.; Feuerbach, S.; Biehl, T.

    1985-01-01

    Three cases are used to demonstrate that intramedullary masses of the tubular bones can be discovered using computered tomography even when changes in the plain film are lacking or discrete. However, it was not possible to differentiate between osteomyelitis, chondrosarcoma and enchondroma owing to the identical morphology of these three diseases. Consequently, CT does not allow any statement on type and dignity and histological clarification is indispensable. (orig./WU) [de

  1. CT five years after myelographic diagnosis of lumbar disk herniation

    Energy Technology Data Exchange (ETDEWEB)

    Hurme, M.; Katevuo, K.; Nykvist, F.; Aalto, T.; Alaranta, H.; Einola, S. (Turku Univ. Central Hospital (Finland). Dept. of Surgery Turku Univ. Central Hospital (Finland). Dept. of Diagnostic Radiology Social Insurance Inst., Turku (Finland). Rehabilitation Research Centre)

    1991-07-01

    Fifty-seven patients were examined with CT 5 years after primary myelography for disabling sciatica and suspected herniated lumbar disk. Forty were in an operated group, 22 with good and 18 with poor results evaluated by occupational handicap (21) 5 years after surgery. Seventeen patients had myelography indicating disk herniation, but were treated conservatively, 9 with good and 8 with poor result. Various spinal dimensions measured at CT did not correlate with outcome. Operated patients had narrower canals than others, and male canals were broader than those in females. Increased amount of scar tissue at L4 level correlated with poor result (p=0.008). Operated patients with poor result had more advanced lateral stenosis than those treated conservatively (p<0.001). Patients with good result after operation had more degeneration observed on CT of erector spinae muscle than those treated conservatively with good outcome. Only 9% of operated patients did not have muscle degeneration. A tendency for more frequent recurrent disk herniations could be ssen for conservatively treated patients. The narrowing of the spinal canal 5 years after operation did not correlate with the 5-year outcome. (orig.).

  2. Floating venous thrombi: diagnosis with spiral-CT-venography

    International Nuclear Information System (INIS)

    Gartenschlaeger, M.; Schmidt, J.A.

    1996-01-01

    Local application of contrast agent into an ipsilateral dorsal foot vein and spiral CT were used to examine 16 consecutive cases with deep venous thrombosis proven at conventional venography; in addition, colour Doppler flow imaging was performed. At conventional venography, 8/16 thrombi appeared to be floating and the remaining 8/16 were adherent to the vessel wall. Spiral-CT showed 15/16 thrombi to be adherent to the vessel wall; the floating thrombus correlated with findings in conventional venography. At colour Doppler flow imaging 3/16 thrombi were considered floating, one of them was discordant to conventional venography. The comparison of conventional venography to spiral-CT demonstrates complete agreement for adherence to vessel wall seen in conventional venography (p=1,0) and significant discordance in cases with free-floating appearance in conventional venography. Adherence of thrombi to the wall of the vessel at conventional venography is in agreement with computed tomography. Conventional venography probably overestimates the prevalence of free floating thrombi. (orig./MG) [de

  3. Acute pulmonary embolism in helical computed tomography

    International Nuclear Information System (INIS)

    Paslawski, M.

    2005-01-01

    Pulmonary embolism is a common condition in which diagnostic and therapeutic delays contribute to substantial morbidity and mortality. Clinical diagnosis is difficult because the signs and symptoms re unspecific, and a differential diagnosis is extensive, including pneumonia or bronchitis, asthma, myocardial infraction, pulmonary edema, anxiety, dissection of the aorta, pericardial tamponade, lung cancer, primary pulmonary hypertension, rib fracture, and pneumothorax. The purpose of the study was to present the use of CT in diagnosing acute pulmonary embolism. A group of 23 patients with clinically suspected pulmonary embolism underwent CT examination with a helical CT scanner (Somatom Emotion, Siemens) before and after administration of 150 ml of Ultravist. Pulmonary embolism was found in the CT examinations of 13 patients. In two of these it was a central filling defect. Amputation of the artery was found in one. Parietal filling defect in three patients formed an acute angle with the vessel walls. Saddle emboli appearing as filling defects in the contrast column that hung over vessel bifurcations was found in two patients. In five patients,emboli were found in small segmental arteries. CT provides information not only on the pulmonary arteries, but also on the lung parenchyma, hila, mediastinum, and the heart. Alternative findings may be identified by CT chest examination, stablishing alternative diagnoses, including pulmonary disorders (such as pneumonia or fibrosis), pleural abnormalities, and cardiovascular disease (such as aortic dissection or pericardial tamponade). Another advantage of the CT is its widespread availability.(author)

  4. MR imaging, CT and CEA scintigraphy in the diagnosis of local recurrence of rectal carcinoma

    International Nuclear Information System (INIS)

    Blomqvist, L.; Holm, T.; Goeranson, H.; Jacobsson, H.; Ohlsen, H.; Larsson, S.A.

    1996-01-01

    Purpose: To compare advanced imaging techniques in the diagnosis of recurrent rectal cancer. Material and Methods: Twenty-five consecutive patients with either suspected or verified recurrence were examined by CT (n=25), MR with phased-array capabilities (n=24) and CEA scintigraphy (n=16). Three experienced radiologists (who were blinded to results obtained at surgery and histopathology) independently evaluated the films, one observer for each modality. Results: The MR radiologist arrived at a correct diagnosis in 87.5% of the examinations, the CT radiologist in 76% and the CEA radiologist in 75%. The MR radiologist's results correlated more often with reported pathology than did those of the CT radiologist with regard to the relation of recurrent tumor to surrounding structures in the pelvis. Conclusion: MR imaging is the most effective of the 3 modalities in the diagnosis of recurrent rectal cancer. (orig.)

  5. Diagnosis of intracranial mixed tumor with CT and MRI (report of 7 cases)

    International Nuclear Information System (INIS)

    Guan Changqun; Zhou Huaiwei; Xue Hongli; Zhang Yuzhong; Hu Lianyuan

    1998-01-01

    Purpose: To recognize the images of intracranial mixed tumor. Materials and methods: Seven cases were studied with CT and MRI. All were proved by pathology, including mixed tumor of meningioma with glioblastoma 2 cases, meningioma with pituitary tumor 2 cases, glioblastoma multiform with angioblastoma 1 cases, cholesteatoma with melanoma 1 case, and pituitary tumor with meningioma 1 case. The authors analysed the CT and MRI manifestations of intracranial mixed tumor retrospectively. Results: The CT and MRI manifestations of intracranial mixed tumor were exactly like meningioma, glioma, and hypophysoma, etc, therefore it was usually misdiagnosed the common tumor. Four cases intracranial mixed tumor displayed two kinds of characteristic CT and MRI manifestation on the same region of the same tumor in contrast with the clinic and pathologic change. Conclusion: There were no characteristic CT and MRI manifestations; the diagnosis should be made in combination with clinical information

  6. Value of CT in the diagnosis of ventilator-associated pneumonia

    International Nuclear Information System (INIS)

    Hahn, U.; Pereira, P.; Laniado, M.; Claussen, C.D.; Heininger, A.

    1999-01-01

    Purpose: To analyse the diagnostic accuracy of computed tomography (CT) in ventilator-associated pneumonia (VAP). Materials and methods: 23 patients on mechanical ventilation with a new pulmonary abnormality on chest X-ray were examined with both spiral-CT and high-resolution CT. The diagnosis VAP was made according to prospectively defined criteria. Bronchoscopic specimen asservation with protected specimen brushing (PSB) served as gold standard. Results: With PSB, 11 of 23 patients were found to have VAP. CT showed a sensitivity and specificity of 53% and 63%, respectively. Ground glass infiltrates appeared to have a 100% specificity but were found in only 5/11 patients. Conclusions: CT is not the method of choice for diagnosing VAP. Groundglass infiltrates seeming to be highly specific are only inconstantly found. (orig.) [de

  7. Free-breathing cine CT for the diagnosis of tracheomalacia in young children

    International Nuclear Information System (INIS)

    Goo, Hyun Woo

    2013-01-01

    Tracheomalacia is characterized by excessive expiratory collapse of the trachea. To investigate the accuracy of free-breathing cine CT for diagnosis of tracheomalacia in young children with bronchoscopy as reference standard. In a retrospective study (May 2001-July 2008), a patient group (n = 27) of children with bronchoscopic evidence of tracheomalacia, and a control group (n = 320) underwent free-breathing cine CT. The tracheal shape on free-breathing cine CT was classified as round, lunate, elongated or crescentic. Cross-sectional area change of the trachea and age were compared between the groups and the diagnostic performance of free-breathing cine CT for tracheomalacia was evaluated. The patient group showed significantly greater cross-sectional area change of the trachea (57.2% ± 22.2% vs. 10.6% ± 11.2%, P < 0.001) than the control group. If a cross-sectional area change of the trachea of 31.6% was used as a cut-off value for the diagnosis of tracheomalacia, the sensitivity, specificity and accuracy of cine CT were 96.3% (26/27), 97.2% (311/320) and 97.1% (337/347), respectively. If a crescentic shape during the expiratory phase was used, the sensitivity, specificity and accuracy were 51.9% (14/27), 98.8% (316/320) and 95.1% (330/347), respectively. Free-breathing cine CT has potential to provide the diagnosis of tracheomalacia in young children. (orig.)

  8. Diagnosis usefulness of CT in meconium pseudocyst in a newborn: A case report

    International Nuclear Information System (INIS)

    Park, Hee Girl; Ki, Kyu Soon; Choi, So Young; Yu, In Kyu

    2014-01-01

    A meconium pseudocyst is rare and may result in the death of the neonate. Meconium pseudocysts should be distinguished from the cystic-type meconium peritonitis because of their differences in the treatment strategy. Various studies have reported the radiographic and sonographic findings of a meconium peritonitis. However, computed tomography (CT) findings of meconium pseudocyst have been rarely reported yet. In this report we present the CT findings of a patient with a meconium pseudocyst. Such CT findings may help in the proper diagnosis and to distinguish the cystic-type meconium peritonitis from the meconium pseudocyst.

  9. Diagnosis usefulness of CT in meconium pseudocyst in a newborn: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hee Girl; Ki, Kyu Soon; Choi, So Young; Yu, In Kyu [Dept. of Radiology, Eulji University Hospital, Daejeon (Korea, Republic of)

    2014-02-15

    A meconium pseudocyst is rare and may result in the death of the neonate. Meconium pseudocysts should be distinguished from the cystic-type meconium peritonitis because of their differences in the treatment strategy. Various studies have reported the radiographic and sonographic findings of a meconium peritonitis. However, computed tomography (CT) findings of meconium pseudocyst have been rarely reported yet. In this report we present the CT findings of a patient with a meconium pseudocyst. Such CT findings may help in the proper diagnosis and to distinguish the cystic-type meconium peritonitis from the meconium pseudocyst.

  10. Role of FDG-PET and PET/CT in the diagnosis and management of vasculitis

    Energy Technology Data Exchange (ETDEWEB)

    Zerizer, Imene; Tan, Kathryn; Khan, Sameer; Barwick, Tara [Department of Nuclear Medicine, Imperial College Healthcare, Hammersmith Hospital, Du Cane Road, London (United Kingdom); Marzola, Maria Cristina [Department of Nuclear Medicine, PET/CT Centre, Radiology and Medical Physics, ' Santa Maria della Misericordia' Hospital, Rovigo (Italy); Rubello, Domenico [Department of Nuclear Medicine, PET/CT Centre, Radiology and Medical Physics, ' Santa Maria della Misericordia' Hospital, Rovigo (Italy)], E-mail: domenico.rubello@libero.it; Al-Nahhas, Adil [Department of Nuclear Medicine, Imperial College Healthcare, Hammersmith Hospital, Du Cane Road, London (United Kingdom)

    2010-03-15

    Purpose: to investigate the role of FDG-PET and PET/CT in the evaluation of vasculitis. Materials and methods: a systematic revision of the papers published in PubMed/Medline until December 2009 was done. Results: FDG-PET and PET/CT have been proven to be valuable in the diagnosis of large-vessel vasculitis, especially giant cells arteritis with sensitivity values ranging 77% to 92%, and specificity values ranging 89% to 100%. In particular, FDG-PET/CT has demonstrated the potential to non-invasively diagnose the onset of the vasculitis earlier than traditional anatomical imaging techniques, thus enabling prompt treatment. False positive results mainly occur in the differential diagnosis between vasculitis and atherosclerotic vessels in elderly patients. Another area where FDG-PET/CT is gaining wider acceptance is in monitoring response to therapy; it can reliably detect the earliest changes of disease improvement post-therapy, and persistent activity is an indicator of non-responders to therapy. A few data have been reported about medium/small vessel vasculitis. Discussion: FDG-PET and PET/CT have proven utility: (a) in the initial diagnosis of patients suspected of having vasculitis particularly in those who present with non-specific symptoms; (b) in the identification of areas of increased FDG uptake in which a biopsy should be done for obtaining a diagnosis; (c) in evaluating the extent of the disease; (d) in assessing response to treatment.

  11. Role of FDG-PET and PET/CT in the diagnosis and management of vasculitis

    International Nuclear Information System (INIS)

    Zerizer, Imene; Tan, Kathryn; Khan, Sameer; Barwick, Tara; Marzola, Maria Cristina; Rubello, Domenico; Al-Nahhas, Adil

    2010-01-01

    Purpose: to investigate the role of FDG-PET and PET/CT in the evaluation of vasculitis. Materials and methods: a systematic revision of the papers published in PubMed/Medline until December 2009 was done. Results: FDG-PET and PET/CT have been proven to be valuable in the diagnosis of large-vessel vasculitis, especially giant cells arteritis with sensitivity values ranging 77% to 92%, and specificity values ranging 89% to 100%. In particular, FDG-PET/CT has demonstrated the potential to non-invasively diagnose the onset of the vasculitis earlier than traditional anatomical imaging techniques, thus enabling prompt treatment. False positive results mainly occur in the differential diagnosis between vasculitis and atherosclerotic vessels in elderly patients. Another area where FDG-PET/CT is gaining wider acceptance is in monitoring response to therapy; it can reliably detect the earliest changes of disease improvement post-therapy, and persistent activity is an indicator of non-responders to therapy. A few data have been reported about medium/small vessel vasculitis. Discussion: FDG-PET and PET/CT have proven utility: (a) in the initial diagnosis of patients suspected of having vasculitis particularly in those who present with non-specific symptoms; (b) in the identification of areas of increased FDG uptake in which a biopsy should be done for obtaining a diagnosis; (c) in evaluating the extent of the disease; (d) in assessing response to treatment.

  12. The contribution of CT-guided transthoracic lung biopsy to the diagnosis of organising pneumonia.

    Science.gov (United States)

    Metzger, F; Pernet, D; Manzoni, P; Ranfaing, E; Dalphin, J-C

    2010-09-01

    Organising pneumonia is a pulmonary disease with variable clinical and radiological features and with many differential diagnoses. Diagnosis is based on histology obtained by either transbronchial or surgical lung biopsy but these techniques have several disadvantages. The aim of this study was to evaluate the diagnostic yield of CT-guided transthoracic lung biopsy in organising pneumonia and to compare it to the usual diagnostic tools. Six cases of organising pneumonia diagnosed with CT-guided lung biopsy are reported and discussed. The role of CT-guided lung biopsy in the diagnosis of organising pneumonia was also reviewed in the literature. CT-guided transthoracic lung biopsies provided a higher rate of adequate samples than transbronchial biopsies (92-100% versus 77-86%). The samples were larger, which reduced the risks of misdiagnosis and increased the diagnostic yield (88-97% versus 26-55% in pulmonary nodules and 42-100% versus 66-75% in diffuse pulmonary disease). Complications were rare and generally not serious. CT-guided transthoracic lung biopsy may be considered in place of transbronchial biopsy in the diagnosis of organising pneumonia. Surgical lung biopsy remains the gold standard method for diagnosis. Copyright © 2010 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  13. Performance of FDG-PET/CT for diagnosis of recurrent uterine cervical cancer

    International Nuclear Information System (INIS)

    Kitajima, Kazuhiro; Murakami, Koji; Yamasaki, Erena; Domeki, Yasushi; Kaji, Yasushi; Sugimura, Kazuro

    2008-01-01

    The purpose is to evaluate the accuracy of integrated FDG-PET/CT, compared with PET alone, for diagnosis of suspected recurrence of uterine cervical cancer. Fifty-two women who had undergone treatment for histopathologically proven cervical cancer received PET/CT with suspected recurrence. PET-alone and integrated PET/CT images were evaluated by two different experienced radiologists by consensus for each investigation. A final diagnosis was confirmed by histopathology, radiological imaging, and clinical follow-up for over 1 year. Patient-based analysis showed that the sensitivity, specificity, and accuracy of PET/CT were 92.0% (23/25), 92.6% (25/27), and 92.3% (48/52), respectively, while for PET, the corresponding figures were 80.0% (20/25), 77.8% (21/27), and 78.8% (41/52), respectively. PET/CT resolved the false-positive PET results due to hypermetabolic activity of benign/inflammatory lesions and physiological variants, and was able to detect lung metastasis, local recurrence, peritoneal dissemination, para-aortic lymph node metastasis, and pelvic lymph node metastasis missed by PET alone. However, tiny local recurrence and lymph node metastasis could not be detected even by PET/CT. FDG-PET/CT is a useful complementary modality for providing good anatomic and functional localization of sites of recurrence during follow-up of patients with cervical cancer. (orig.)

  14. Value of multi-slice spiral CT MPVR reconstruction in the diagnosis of acute appendicitis

    International Nuclear Information System (INIS)

    Wang Kang; Zhao Zehua; Wang Zhi; Wang Weizhong; Xu Songsen; Zhang Miao; Liu Wenjin; Zhang Guozhen; Feng Dianxu

    2005-01-01

    Objective: To investigate the value of multi-slice spiral CT MPVR reconstruction in the diagnosis of acute appendicitis. Methods: A total of 39 patients with clinically suspected acute appendicitis underwent surgery from February, 2002 to September, 2003. They were prospectively examined before surgery with routine CT scanning and MPVR reconstruction spiral CT. 31 cases of appendicitis were confirmed after appendectomy. CT scans and surgery-pathology reports were evaluated on a five-grade scale from hyperemic-edematous appendix to abscess (normal appendix: 0 grade). Results: The results of spiral CT MPVR reconstruction were compared with the surgical and pathologic findings at appendectomy, yielding an accuracy of 87.2%, sensitivity of 90.3%, specificity of 75%, positive predictive value of 93.3%, and negative predictive value of 66.7%, respectively. Results of routine CT yielded an accuracy of 38.5%, sensitivity of 38.7%, specificity of 37.5%, positive predictive value of 70.6%, and negative predictive value of 13.6%, respectively. MPVR reconstruction signs of 28 patients with acute appendicitis included enlarged appendix ( > 6 mm) (96.4%), appendicoliths (26.7%), caecal apical thickening (36.7%), periappendiceal inflammation (71.4%), and abscess (10.7%). Conclusion: The use of spiral CT MPVR reconstruction in patients with equivocal clinical presentation suspected of having acute appendicitis can lead to a significant improvement in the preoperative diagnosis and maybe a decrease in surgical-pathologic severity of appendiceal disease. (authors)

  15. Basic pattern in CT of the lung and differential diagnosis

    International Nuclear Information System (INIS)

    Jacobi, V.; Thalhammer, A.

    2006-01-01

    Infectious, physical, chemical or other noxae elicit a limited number of reactions in lung tissue. As in the case of other organs and tissues, lung tissue has specific reactions that are often more indicative of the particular organ than the harmful agent. The resulting radiological features are usually ambiguous and therefore prevent definitive diagnosis. This complicates etiological categorization of the disease. Pathognomonic findings are rare. The same noxa can yield different radiographic features and clinical pictures for different patients. A diagnosis is generally not comprised of a single radiographic feature, but rather of a combination of a plurality of features. Although the number of possible diagnoses can be limited via radiological means, a final diagnosis is determined in conjunction with the medical history, the clinical picture, as well as lab and histopathological values. This article defines the most common pulmonary changes and also discusses differential diagnostic criteria. (orig.)

  16. Iatrogenic intraspinal epidermoid tumor: Myelo-CT and MRI diagnosis

    Energy Technology Data Exchange (ETDEWEB)

    Visciani, A.; Balestrini, M.R.; Solero, C.L.; Savoiardo, M.

    1989-07-01

    An 11-year-old boy, treated for acute lymphatic leukemia at the age of 2 with intrathecal injections of Methotrexate, presented with a two year history of pain and signs of lumbo-sacral lesion. MRI, myelography and myelo-CT demonstrated an intradural L4-L5 epidermoid tumor which was removed. Iatrogenic implantation of epithelial cells at the age of two with lumbar punctures is most likely. Decline in incidence of lumbar iatrogenic epidermoid cysts, now an exceedingly rare event, is probably related to improved needles for lumbar punctures. (orig.).

  17. Iatrogenic intraspinal epidermoid tumor: Myelo-CT and MRI diagnosis

    International Nuclear Information System (INIS)

    Visciani, A.; Balestrini, M.R.; Solero, C.L.; Savoiardo, M.

    1989-01-01

    An 11-year-old boy, treated for acute lymphatic leukemia at the age of 2 with intrathecal injections of Methotrexate, presented with a two year history of pain and signs of lumbo-sacral lesion. MRI, myelography and myelo-CT demonstrated an intradural L4-L5 epidermoid tumor which was removed. Iatrogenic implantation of epithelial cells at the age of two with lumbar punctures is most likely. Decline in incidence of lumbar iatrogenic epidermoid cysts, now an exceedingly rare event, is probably related to improved needles for lumbar punctures. (orig.)

  18. Leigh's subacute necrotizing encephalomyelopathy: Possible diagnosis by CT scan

    International Nuclear Information System (INIS)

    Chi, J.G.; Yoo, H.W.; Chang, K.H.; Kim, C.W.; Moon, H.R.; Ko, K.W.

    1981-01-01

    A 28-month-old Korean girl developed a rapidly progressive disease, characterized by disturbance of consciousness, tremor, nystagmus, ophthalmoplegia, irregular deep respiration and vomiting. The patient succumbed 2 weeks after the onset of the illness. CT scan disclosed bilaterally symmetrical, low density lesions in the white matter and lateral basal ganglia. Distinctive histopathological findings at postmortem included spongiotic necrosis of the neuropil, marked capillary vascularity, persistence of relatively normal neurons in severely damaged zones, and comparatively little astrocytosis. The bilaterally symmetrical distribution of these changes in the putamen and periaqueductal gray matter of the midbrain were compatible with Leigh's disease. (orig.)

  19. Diagnosis of anemia on CT scans of the thorax

    International Nuclear Information System (INIS)

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

    1986-01-01

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

  20. Renal infarction: CT diagnosis and correlation between CT findings and etiologies

    International Nuclear Information System (INIS)

    Wong, W.S.; Moss, A.A.; Federle, M.P.; Cochran, S.T.; London, S.S.

    1984-01-01

    The CT scans and the clinical records of 12 patients who had renal infarction were reviewed. The renal infarcts were classified as either focal or global. The CT findings were correlated with the etiologies of renal infarction. Embolism was the most common cause of renal infarcts that were multifocal with involvement of both kidneys. Trauma caused a unilateral global type of infract. A case of sickle cell anemia presented with multiple ''slit-like'' focal infarcts and enlarged kidneys. Forty-seven per cent of infarcts demonstrated the cortical rim sign, 11% were acapsular fluid collection, and 6% had an abnormally thickened renal fascia

  1. CT diagnosis of recurrence following resection for gastric carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Cho, On Koo; Cho, Hye Young; Kim, Soon Yong [Hanyag University College of Medicine, Seoul (Korea, Republic of)

    1988-10-15

    There is almost complete lack of specific reference to the findings of recurrent gastric carcinoma except a few data which have been based on autopsy findings. The purpose of this study is to demonstrate the usefulness of CT for defining the pattern of recurrence and to compare the results of convectional barium studies to identify the lesion. 1. There were 64 cases of postgastrectomy CT scan of gastric carcinoma during recent 3 years and recurrence evidence was identified in 53 cases. 2. Time lapse between operation and detection of recurrence was variable from 3 months to 6 years. Evidence of recurrence less than 1 year were stage III and IV patients and long survivors more than 5 years were stage I and III patients. 3. Local recurrence of gastric remnant or anastomosis area was identified in 10 cases. Regional recurrence was noted in 28 cases including 13 gastric bed and 26 lymph node enlargement. Most frequently enlarged nodes were peripancreatic and paraaortic nodes. 4. Peritoneal spread was the most frequent pattern of recurrence occurring in 34 cases. Mesenteric mass and ascites were most frequent findings. 5. Distant metastasis was noted in 12 cases and the liver was the most frequent site. 6. Local recurrence was detected in barium study in half of the cases. Peritoneal seeding was relatively well identified but regional recurrence was very poorly identified.

  2. CT and scintiscanning - complementary diagnosis of morph and function

    International Nuclear Information System (INIS)

    Buell, U.

    1981-01-01

    Computed axial transmission tomography, static scintiscanning and functional scintiscanning are compared using the liver and the brain as organs of reference. The parameters employed are sensitivity, specificity and accuracy. The value of the methods in differential diagnosis is discussed. (WU) [de

  3. Radiation dose reduction at a price: the effectiveness of a male gonadal shield during helical CT scans

    OpenAIRE

    Erdi Yusuf E; Casciotta Kevin A; Dauer Lawrence T; Rothenberg Lawrence N

    2007-01-01

    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...

  4. The role of CT and MR in diagnosis of aortic dissection

    International Nuclear Information System (INIS)

    Yoon, Kwon Ha; Lim, Tae Hwan; Song, Koun Sik; Min, Kyung Seok; Song, Meong Gun

    1994-01-01

    The purpose of this study was to determine the role of CT and MR imagings in the diagnosis of aortic dissection and differentiation between the true and false lumen. We retrospectively studied forty patients with aortic dissection(AD) diagnosed by imagings or surgery. Of the forty patients, 19 were examined with only CT, 14 with CT and MR, and 7 with MR. Our points of view were(1) the classification of AD according to configuration of intimal flap by cross-sectional imaging, (2) differentiation between the true and false lumens, (3) the course of the false lumen, and (4) detectability of the origin of major branch vessels of the abdominal aorta. The classification by cross-sectional imaging were crescentic(65%), circumferential(15%), flat(12%), and irregular(8%) type, in which false negative diagnosis was made in 1 case of crescentic and circumferential type, respectively. In 2 case of flat type and 1 case of irregular type, the differentiation between the true and false lumen was impossible with CT. The course of the false lumen in descending thoracic aorta revealed counterclock wise rotation(66%), clockwise rotation(5%) or fixed(29%) appearance. MR imaging was superior to CT in the detection of the origin of major branch vessels of the abdominal aorta. The determination of the origin of major branches of abdominal aorta arising from the true and false lumen were impossible in 2 cases in which only CT was done. Diagnosis of crescentic and circumferential types of AD with narrow and thrombosed false lumen was problematic in both CT and MR with no difference of diagnostic accuracy between the two modalities. The differentiation between the true and false lumen was difficult in flat and irregular types with only CT. Therefore, when surgical treatment is considered as in type B aortic dissection, MR imaging is recommended in order to determine the origin of major branch vessels

  5. Utility of Megavoltage Fan-Beam CT for Treatment Planning in a Head-And-Neck Cancer Patient with Extensive Dental Fillings Undergoing Helical Tomotherapy

    International Nuclear Information System (INIS)

    Yang, Claus; Liu Tianxiao; Jennelle, Richard L.; Ryu, Janice K.; Vijayakumar, Srinivasan; Purdy, James A.; Chen, Allen M.

    2010-01-01

    The purpose of this study was to demonstrate the potential utility of megavoltage fan-beam computed tomography (MV-FBCT) for treatment planning in a patient undergoing helical tomotherapy for nasopharyngeal carcinoma in the presence of extensive dental artifact. A 28-year-old female with locally advanced nasopharyngeal carcinoma presented for radiation therapy. Due to the extensiveness of the dental artifact present in the oral cavity kV-CT scan acquired at simulation, which made treatment planning impossible on tomotherapy planning system, MV-FBCT imaging was obtained using the HI-ART tomotherapy treatment machine, with the patient in the treatment position, and this information was registered with her original kV-CT scan for the purposes of structure delineation, dose calculation, and treatment planning. To validate the feasibility of the MV-FBCT-generated treatment plan, an electron density CT phantom (model 465, Gammex Inc., Middleton, WI) was scanned using MV-FBCT to obtain CT number to density table. Additionally, both a 'cheese' phantom (which came with the tomotherapy treatment machine) with 2 inserted ion chambers and a generic phantom called Quasar phantom (Modus Medical Devices Inc., London, ON, Canada) with one inserted chamber were used to confirm dosimetric accuracy. The MV-FBCT could be used to clearly visualize anatomy in the region of the dental artifact and provide sufficient soft-tissue contrast to assist in the delineation of normal tissue structures and fat planes. With the elimination of the dental artifact, the MV-FBCT images allowed more accurate dose calculation by the tomotherapy system. It was confirmed that the phantom material density was determined correctly by the tomotherapy MV-FBCT number to density table. The ion chamber measurements agreed with the calculations from the MV-FBCT generated phantom plan within 2%. MV-FBCT may be useful in radiation treatment planning for nasopharyngeal cancer patients in the setting of extensive

  6. CT diagnosis and differential diagnosis of masses located in the junctional space adjacent to stomach, spleen and pancreas

    International Nuclear Information System (INIS)

    Hu Xueling

    2006-01-01

    Objective: To study the CT diagnosis and differential diagnosis of masses located in the junctional space adjacent to stomach, spleen and pancreas, with analysis of cases in which misdiagnosis was made. Methods: CT manifestations were retrospectively investigated in 20 cases of masses located in the junctional space adjacent to stomach, spleen and pancreas. Lesions had been located with the images and then qualitative diagnosis had been made. All the cases were eventually confirmed by pathology. Results: The lesions were in round shape in 6 cases out of 20 irregular masses were revealed in 14 showed, unclear demarcated lesions were showed in 16 cases. Inhomogeneous enhancement of the masses was visualized when the contrast agent was given. The central spot and maximum plain of the mass were different among different pathology types of the masses. 6 of 20 were original from stomach, 7 of 20 from pancreas, 3 from spleen and 4 from peritoneal cavity. 6 of 20 were wrong located (30%), 8 of 20 (40%)were wrong pathological diagnosis. Conclusion: Location is more important than pathological character diagnosis. It is valuable to locate the maximum plain of the masses and shape changed of organs nearby. (authors)

  7. Tuberous sclerosis: Improvement of diagnosis by CT and MRI

    International Nuclear Information System (INIS)

    Dewes, W.; Henkes, H.; Richter, J.; Kretschmer, A.; Benz, P.; Brill, G.

    1992-01-01

    Ten children and a 22-y old women with tuberous sclerosis were studied. All children were epileptic but only 8 had skin lesions (white spots, adenoma sebaceum), 4 had rhabdomyoma of the heart and 4 children had strocytoma of the retina; only in 4 children was the entire triad of tuberous sclerosis seen. The young woman with a hemorrhage of an angiolipoma of the kidney had no other symptoms of tuberous sclerosis. All patients had pathologic CT and MRT findings; 4 different types of lesion were seen in MRT. In order to elucidate humangenetic aspects and to demonstrate the underlying disease all children with epileptic disorders and also all patients without the full triad of symptoms should be examined by MRT. (orig.) [de

  8. Diagnosis of Peripheral Lung Lesions via Conventional Flexible Bronchoscopy with Multiplanar CT Planning

    Directory of Open Access Journals (Sweden)

    Marianne Anastasia De Roza

    2016-01-01

    Full Text Available Background. Conventional flexible bronchoscopy has limited sensitivity in the diagnosis of peripheral lung lesions and is dependent on lesion size. However, advancement of CT imaging offers multiplanar reconstruction facilitating enhanced preprocedure planning. This study aims to report efficacy and safety while considering the impact of patient selection and multiplanar CT planning. Method. Prospective case series of patients with peripheral lung lesions suspected of having lung cancer who underwent flexible bronchoscopy (forceps biopsy and lavage. Endobronchial lesions were excluded. Patients with negative results underwent CT-guided transthoracic needle aspiration, surgical biopsy, or clinical-radiological surveillance to establish the final diagnosis. Results. 226 patients were analysed. The diagnostic yield of bronchoscopy was 80.1% (181/226 with a sensitivity of 84.2% and specificity of 100%. In patients with a positive CT-Bronchus sign, the diagnostic yield was 82.4% compared to 72.8% with negative CT-Bronchus sign (p=0.116. Diagnostic yield was 84.9% in lesions > 20 mm and 63.0% in lesions ≤ 20 mm (p=0.001. Six (2.7% patients had transient hypoxia and 2 (0.9% had pneumothorax. There were no serious adverse events. Conclusion. Flexible bronchoscopy with appropriate patient selection and preprocedure planning is more efficacious in obtaining a diagnosis in peripheral lung lesions compared to historical data. This trial is registered with ClinicalTrials.gov Identifier: NCT01374542.

  9. Normal width of the anterior commissure of true vocal cord in Korea adults measured by helical CT

    International Nuclear Information System (INIS)

    Lim, Woo Young; Lim, Dong Hoon; Moon, Jang Il; Ko, Yong Seok; Byeon, Joo Nam; Oh, Jae Hee

    1998-01-01

    To evaluate the mean width of anterior commissure of true vocal cord in Korean adults by measuring its dimension on spiral CT scans. We reviewed the CT scans of 53 Korean adults(age range, 23-73years; mean age 39.2 years;M:F=3D41:12) without laryngeal disorders. Soiral CT scanning was performed around the anterior commissure with 1mm slice thickness and table incrementation for 15 seconds. The anteroposterior width of the anterior commissure was measured on CT scan where the true vocal cord and arytenoid, cricoid and thyroid cartilages were all present. We determined the mean width of the anterior commissure and whether there was a relationship between age and the width of the anterior commissure. The width of the anterior commissure was between 0.9mm and 2.3mm;mean width was 1.60±0.38mm(mean±SD). Using two SDs above the mean would have defined 2.36mm as the upper limit of normal width. Statistically, no significant correlation existed between the age and the width of the anterior commissure(p>0.05). An awareuess of the normal width range of the anterior commissure in Korean adults evaluated by spiral CT enhances the possibility of early detection of invasion of the anterior commissure by glottic cancer.=20

  10. Dosimetry of patients submitted to cerebral PET/CT for the diagnosis of mild cognitive impairment

    Energy Technology Data Exchange (ETDEWEB)

    Santana, Priscila do Carmo; Oliveira, Paulo Marcio Campos de; Bernardes, Felipe Dias; Mamede, Marcelo, E-mail: pridili@gmail.com [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil); Mourao, Arnaldo Prata [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET), Belo Horizonte, MG (Brazil); Silva, Teogenes Augusto da [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2014-11-15

    Objective: the present study was aimed at evaluating the effective radiation dose in patients submitted to PET/CT for the diagnosis of mild cognitive impairment. Materials and methods: TLD-100 detectors inserted into an Alderson Rando® anthropomorphic phantom were utilized to measure the absorbed dose coming from the CT imaging modality. The anthropomorphic phantoms (male and female adult versions) were submitted to the same technical protocols for patients’ images acquisition. The absorbed dose resulting from the radiopharmaceutical injection was estimated by means of the model proposed by the ICRP publication 106. Results: the effective dose in patients submitted to this diagnostic technique was approximately (5.34 ± 1.99) mSv. Conclusion: optimized protocols for calculation of radioactive activity injected into patients submitted to this diagnostic technique might contribute to reduce the effective radiation dose resulting from PET/CT in the diagnosis of mild cognitive impairment. (author)

  11. Myocardial CT perfusion imaging and SPECT for the diagnosis of coronary artery disease

    DEFF Research Database (Denmark)

    George, Richard T; Mehra, Vishal C; Chen, Marcus Y

    2014-01-01

    %, respectively, for SPECT. CONCLUSION: The overall performance of myocardial CT perfusion imaging in the diagnosis of anatomic CAD (stenosis ≥50%), as demonstrated with the Az, was higher than that of SPECT and was driven in part by the higher sensitivity for left main and multivessel disease.......PURPOSE: To compare the diagnostic performance of myocardial computed tomographic (CT) perfusion imaging and single photon emission computed tomography (SPECT) perfusion imaging in the diagnosis of anatomically significant coronary artery disease (CAD) as depicted at invasive coronary angiography....... MATERIALS AND METHODS: This study was approved by the institutional review board. Written informed consent was obtained from all patients. Sixteen centers enrolled 381 patients from November 2009 to July 2011. Patients underwent rest and adenosine stress CT perfusion imaging and rest and either exercise...

  12. Dosimetry of patients submitted to cerebral PET/CT for the diagnosis of mild cognitive impairment

    International Nuclear Information System (INIS)

    Santana, Priscila do Carmo; Oliveira, Paulo Marcio Campos de; Bernardes, Felipe Dias; Mamede, Marcelo; Mourao, Arnaldo Prata; Silva, Teogenes Augusto da

    2014-01-01

    Objective: the present study was aimed at evaluating the effective radiation dose in patients submitted to PET/CT for the diagnosis of mild cognitive impairment. Materials and methods: TLD-100 detectors inserted into an Alderson Rando® anthropomorphic phantom were utilized to measure the absorbed dose coming from the CT imaging modality. The anthropomorphic phantoms (male and female adult versions) were submitted to the same technical protocols for patients’ images acquisition. The absorbed dose resulting from the radiopharmaceutical injection was estimated by means of the model proposed by the ICRP publication 106. Results: the effective dose in patients submitted to this diagnostic technique was approximately (5.34 ± 1.99) mSv. Conclusion: optimized protocols for calculation of radioactive activity injected into patients submitted to this diagnostic technique might contribute to reduce the effective radiation dose resulting from PET/CT in the diagnosis of mild cognitive impairment. (author)

  13. Diagnosis and staging of breast cancer by SPECT images fused with CT images

    International Nuclear Information System (INIS)

    Li Yanjing; Zhu Qiaomei

    2007-01-01

    Objective: To evaluate the TNM staging value of 99mTc-MIBI scintimammotraphy with SPECT-CT images fusing for the diagnosis of breast cancer. Methods: 10 patients with breast cancer underwent scintimammography with 99mTc-MIBI, and SPECT images were fused with CT images. Images were compared with final diagnosis confirmed by histopathology. Results: Of the 19 breast cancer patients, one case of invasive ductal carcinoma showed false-negative. Among 18 cases of positive lesions, axillary metastases were involved in 10, supraclavicular nodes were also defined in 3, para-sternum nodes were involved in 2, 2 were missed and 1 cases without metastatic node. The axillary lymph nodes were divided into three levels with respect to their position relative to the pectoralis minor muscle by fused images. Conclusion: 99mTc-MIBI scintimammotraphy combined with SPECT-CT images fusing is of some clinical value in TNM staging of breast cancer. (authors)

  14. Renal angiomyolipoma without visible fat. Can we make the diagnosis using CT and MRI?

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Robert S.; McInnes, Matthew D.F.; Schieda, Nicola [The University of Ottawa, Department of Medical Imaging, The Ottawa Hospital, Ottawa, Ontario (Canada); Flood, Trevor A. [The University of Ottawa, Department of Anatomical Pathology, The Ottawa Hospital, Ottawa, Ontario (Canada); Lavallee, Luke T. [The University of Ottawa, Department of Surgery, Division of Urology, The Ottawa Hospital, Ottawa, Ontario (Canada)

    2018-02-15

    Renal angiomyolipomas without visible fat (AML.wovf) are benign masses that are incidentally discovered mainly in women. AML.wovf are typically homogeneously hyperdense on unenhanced CT without calcification or haemorrhage. Unenhanced CT pixel analysis is not useful for diagnosis. AML.wovf are characteristically homogeneously hypointense on T2-weighted (T2W)-MRI and apparent diffusion coefficient (ADC) maps. Despite early reports, only a minority of AML.wovf show signal intensity drop on chemical-shift MRI due to microscopic fat. AML.wovf most commonly show avid early enhancement with washout kinetics at contrast-enhanced CT and MRI. The combination of homogeneously low T2W and/or ADC signal intensity with avid early enhancement and washout is highly accurate for diagnosis of AML.wovf. (orig.)

  15. Case Report: CT diagnosis of thymic remnant cyst/thymopharyngeal duct cyst

    International Nuclear Information System (INIS)

    Daga, Bipin V; Chaudhary, VA; Dhamangaokar, VB

    2009-01-01

    A 4-year-old boy presented with history of left anterolateral neck swelling since birth. He was clinically diagnosed to have a branchial cleft cyst. A CT scan revealed findings suggestive of a thymic remnant cyst. The lesion was excised and the diagnosis was confirmed by histopathology

  16. Comparison of CT and MRI for Diagnosis of Suspected Scaphoid Fractures

    NARCIS (Netherlands)

    Mallee, Wouter; Doornberg, Job N.; Ring, David; van Dijk, C. Niek; Maas, Mario; Goslings, J. Carel

    2011-01-01

    Background: There is no consensus on the optimum imaging method to use to confirm the diagnosis of true scaphoid fractures among patients with suspected scaphoid fractures. This study tested the null hypothesis that computed tomography (CT) and magnetic resonance imaging (MRI) have the same

  17. Experience of CT Guided Procedures in the Diagnosis of 55 patients ...

    African Journals Online (AJOL)

    All fine needle aspirations were performed with 20-gauge needles while core tissue biopsies were performed with 14 –gauge needles under CT guidance. The diagnostic yield of these procedures, complications, and patient's feedback were studied. Results: Diagnosis was malignant lesions in 18(32.1%), benign in ...

  18. Widening of mediastinum with persistent left superior Vena cava - CT diagnosis

    International Nuclear Information System (INIS)

    Neuwirth, J.; Kolar, J.

    1992-01-01

    Described in this paper are radiographic findings recorded from a case of persistent left superior vena cava which grew manifest by widening of the left contour of the upper mediastinal region. Contrast-enhanced computed tomography (CT) was undertaken to clear up suspicion of mediastinal tumour and revealed double superior vena cava. The diagnosis was then confirmed by digital subtraction venography. (orig.) [de

  19. Head trauma and CT with special reference to diagnosis of complications of head trauma

    International Nuclear Information System (INIS)

    Samejima, Kanji; Yoshii, Nobuo; Tobari, Chitose

    1979-01-01

    Cases in which CT was useful for the diagnosis of complications of head trauma were reported. First, complications of head trauma were given an outline, and then, cases of protrusion of the brain, traumatic pneumocephalus, and cerebro-vascular disorders caused by head trauma were mentioned. (Tsunoda, M.)

  20. Assess PET/MR in diagnosis of disease in comparison with PET/CT

    International Nuclear Information System (INIS)

    Yan, Jianhua; Lim, Jason Chu-Chern; Loi, Hoi Yin; Totoman, John; Sinha, Arvind Kumar; Quek, Swee Titan; Townsend, David

    2015-01-01

    The aim of this study is to assess the performance of 18F-FDG whole body PET/MRI in comparison with PET/CT based on SUV. Anatomical location of lesion with Dixon MRI and additional value of advanced MRI technology such as diffusion weighted MR imaging in diagnosis of malignant disease will also be investigated.

  1. Clinical application and progress of PET and PET-CT for differential diagnosis of the benign or malignant pulmonary nodules

    International Nuclear Information System (INIS)

    Wang Xuemei; Wang Meiling; Wang Xiangcheng

    2010-01-01

    To differential diagnosis the benign or malignant of pulmonary nodules is a medical difficult problem. As the development of medical imaging equipment and technology, PET-CT can identified benign or malignant lesions of pulmonary nodules though changes of metabolism. Researches about PET-CT for differential diagnosis pulmonary nodules benign or malignant are reviewed. (authors)

  2. Application of SPECT/CT imaging in the diagnosis of benign diseases

    International Nuclear Information System (INIS)

    Garcheva, M.; Demirev, A.

    2014-01-01

    The application of recently introduced hybrid nuclear medicine methods gains importance in a variety of clinical fields, mainly because of the unique combination between functional and anatomical data provided by those methods and their capability for a precise localization of pathological processes. Single photon emission computed tomography, combined with computed tomography (SPECT/CT) is one of those methods. Its role in nuclear cardiology is important, because it provides quick attenuation correction and calculates the calcium score. In nuclear endocrinology SPECT/CT participates in thyroid and parathyroid examinations, especially in cases, where there is a need for localization of ectopic parathyroid or thyroid tissue. In nuclear pulmonology, one of the best ways to attribute certain changes seen on the SPECT, to the zone of interest on the CT, is to study the fused images obtained from the SPECT/ CT scanner. In cases of suspected infection and inflammation, fused images are indispensable for accurate localization of the involved tissue (structure) and for discrimination between normal/abnormal uptake. Careful reading of the CT component (even low-dose) is related (in 10% of cases) to clinically important incidental findings: effusions, tumors, metastases or lymph node pathology. SPECT/CT increases the specificity of the examinations and improves significantly the localization of pathological processes. It provides additional information, shortens the diagnostic algorithm and influences the extent of surgical procedures. In many hybrid examinations the preferred CT component is a low-dose one, without considerable radiation exposure. The opportunity to combine nuclear medicine techniques and contrast CT images, aiming at better diagnosis needs further development. SPECT/CT provides important additional information and more accurate diagnostics in patients with benign diseases. (authors) Key words: SPECT/CT. BENIGN DISEASES

  3. Macromodular splenic tuberculosis in a medically-treated AIDS patient: diagnosis and management by CT

    International Nuclear Information System (INIS)

    Galant, J., Marti-Bonmati, L.; Tornero, C.; Ferrer, M.D.

    1995-01-01

    We used computerized tomography (CT) in the study of eight patients with macronodular splenic tuberculosis prior to the microbiological diagnosis. These patients underwent additional CT controls during and after tuberculostatic therapy. All the patients studed presented the acquired immunodeficiency syndrome (AIDS). Splenomegaly and numerosous round, hypodense lesions that showed no contrast uptake were found in all the subjects. Only three patients presented evidence of tuberculosis in plain radiography and/or chest X-ray. Two patients presented abdominal lymph nodes. None of them showed evidence of hepatic lesions or ascites. follow-up CT scans revealed a progressive reduction of the lesions, which eventually disappeared completely, and splenomegaly was considerably reduced. Anthough it is uncommon, we should suspect splenic involvement in tuberculosis if the clinical and radiological contexts are appropriate. CT provides excellent monitoring of the efficacy of treatment in these patients. 17 refs

  4. Artificial intelligence aiding the thin-section CT diagnosis of diffuse pulmonary diseases

    International Nuclear Information System (INIS)

    Han, Dae Hee; Koh, Young Hwan; Seong, Chang Kyu; Kim, Ji Hoon; Choi, Young Ho; Kim, Jong Hyo; Chae, Young Moon; Lee, Yun Hee; Han, Heon

    2006-01-01

    We wanted to develop and test an artificial intelligence (AI) to assist physicians in making the thin-section CT diagnosis of diffuse pulmonary diseases. The AI was composed of knowledge bases (KB) of 12 diffuse pulmonary diseases and an inference engine (IE). The KB of a disease included both the inclusion criteria (IC) and the exclusion criteria (EC), which were the clinical or thin-section CT findings that were known to be present or absent in that particular disease, respectively. From imputing the clinical or thin-section CT findings by the operator who was reading the thin-section CT, AI instantly executed the following two steps. First, the IE eliminated all diseases from the list which the EC had for those particular findings. Next, from a list or remaining diseases, the AI selected those diseases having those findings in its IC to formulate the 1st-step differential diagnosis (DD1). For the differential diagnosis in the next step, the reader could choose one more clinical or thin-section CT finding from the new list: [(all the findings in the IC or EC of DD1)-(the findings in the IC common to all the DD1s)]. The reader could proceed even further if needed. The system was tested on 10 radiology residents who solved 24 problems (two problems for each of 12 diffuse pulmonary diseases) without and then with the aid of the AI. The scores were compared using the Wilcoxon signed rank test. An AI was made; it was composed of 280 rules (214 IC and 66 EC) and there interfaces (two for program management and another for problem solving). Contestants scored higher (ρ = 0.0078) using the AI (167 vs. 110 respectively), and they responded that they felt that the program was helpful in making decisions. AI appeared to be helpful in making thin-section CT diagnosis

  5. Artificial intelligence aiding the thin-section CT diagnosis of diffuse pulmonary diseases

    Energy Technology Data Exchange (ETDEWEB)

    Han, Dae Hee; Koh, Young Hwan; Seong, Chang Kyu; Kim, Ji Hoon; Choi, Young Ho [Boramae Munincipal Hospital, Seoul National University College of Medicine, Seoul (Korea, Republic of); Kim, Jong Hyo [Seoul National University College of Medicine, Seoul (Korea, Republic of); Chae, Young Moon [Yonsei University Graduate School of Public Heath, Seoul (Korea, Republic of); Lee, Yun Hee [The Graduate School of Imformation, Yonsei, Seoul (Korea, Republic of); Han, Heon [Kangwon National University College of Medicine, Chuncheon (Korea, Republic of)

    2006-06-15

    We wanted to develop and test an artificial intelligence (AI) to assist physicians in making the thin-section CT diagnosis of diffuse pulmonary diseases. The AI was composed of knowledge bases (KB) of 12 diffuse pulmonary diseases and an inference engine (IE). The KB of a disease included both the inclusion criteria (IC) and the exclusion criteria (EC), which were the clinical or thin-section CT findings that were known to be present or absent in that particular disease, respectively. From imputing the clinical or thin-section CT findings by the operator who was reading the thin-section CT, AI instantly executed the following two steps. First, the IE eliminated all diseases from the list which the EC had for those particular findings. Next, from a list or remaining diseases, the AI selected those diseases having those findings in its IC to formulate the 1st-step differential diagnosis (DD1). For the differential diagnosis in the next step, the reader could choose one more clinical or thin-section CT finding from the new list: [(all the findings in the IC or EC of DD1)-(the findings in the IC common to all the DD1s)]. The reader could proceed even further if needed. The system was tested on 10 radiology residents who solved 24 problems (two problems for each of 12 diffuse pulmonary diseases) without and then with the aid of the AI. The scores were compared using the Wilcoxon signed rank test. An AI was made; it was composed of 280 rules (214 IC and 66 EC) and there interfaces (two for program management and another for problem solving). Contestants scored higher ({rho} = 0.0078) using the AI (167 vs. 110 respectively), and they responded that they felt that the program was helpful in making decisions. AI appeared to be helpful in making thin-section CT diagnosis.

  6. Results of CT in the diagnosis of recurrence of colorectal carcinomas

    Energy Technology Data Exchange (ETDEWEB)

    Majewski, A.; Haubitz, B.; Laprell, H.

    1983-06-01

    Postoperative CT was performed in 179 colo-rectal carcinoma patients who had undergone abdominoperineal extirpation (n = 71), resection and rectosigmoid anastomosis (n = 37), hemicolectomy (n = 32), resection of sigma (n = 31), and others (n = 8). Normal CT-findings were found in 25% only, in more than 75% of all cases pathological CT-findings were seen. CT detected loxal recurrence in 87 patients. Based on CT findings local recurrent colo-rectal carcinoma was classified as Stage 0, or intraluminal mass, in 2 patients (2%). Stage 1, or extraluminal mass without invasion of adjacent organs, was found in 38 (44%) patients; Stage 2a, tumor mass with direct invasions of adjacent organs but not the pelvic side walls could be demonstrated in 13 (15%) of the cases; Stage 2b, for extension of mass to pelvic side walls, and Stage 3, or distant metastatic disease, was found in 14 (16%) and 20 (23%) patients. CT was negative in 2 patients with local recurrence (beside Stage 0), an incorrect diagnosis of recurrence due postoperative scarring was found in 4 patients. CT detected exclusive also metastatic disease of the liver in 23 patients and intraabdominal lymph node involvement in 8 patients.

  7. CT diagnosis of hepatic alveolar echinococcosis and evaluation after albendazole chemotherapy

    International Nuclear Information System (INIS)

    Wu Jingquan; Liu Yuehan; Wang Xiaogen

    1998-01-01

    Purpose: To analyze the CT features and evaluate albendazole chemotherapy of hepatic alveolar echinococcosis with computed tomography (CT). Methods: Twenty-one patients of hepatic alveolar echincoccosis were diagnosed by epidemiological, clinical, serological tests, and studied with US and CT. Twenty patients were followed up by CT scanning from 1 to 9 years (mean 3.9 years) after albendazole chemotherapy. Results: CT scanning of liver before treatment displayed heterogeneous hypodense lesions, with irregular, obscure contour and calcifications According to CT features, the hepatic lesions were divided into 3 forms: solid mass in 7 cases, pseudocyst in 6 cases and mixed in 8 cases. Three patients had contrast study. The hepatic lesions were not markedly enhanced, but the lesions were seen more clearly and appeared more extensive. In follow-up examination of 20 cases, 4 were apparently cured, 5 improved, 5 stabilized, and 6 cases remained pseudocyst. Conclusion: CT scanning was of value not only for diagnosis of hepatic alveolar echinococcosis, but also useful in evaluation of chemotherapeutic efficacy

  8. Application of 18F-FDG PET/CT for the diagnosis of cervical cancer

    International Nuclear Information System (INIS)

    Zhou Wenlan; Wu Hubing; Wang Quanshi; Ye Xianghua

    2008-01-01

    Objective: The purpose of this study was to evaluate the clinical value of 18 F-fluorode-oxyglucose (FDG) PET/CT for staging and re-staging cervical cancer cases. Methods: This retrospective study included 88 patients. Of the 88 patients, 19 were primary cervical cancer, 11 were benign cervical tumor and 58 were cervical cancer patients with post-treatment surveillance. All had either whole body or abdominal-pelvic FDG PET/CT imaging. The diagnosis was established according to the pathologic results of surgery or biopsy, and(or) multi-modality imaging and clinical follow-up for at least six months. Results: For initial diagnosis of cervical cancer, the sensitivity, specificity and accuracy of FDG PET/CT were 17/19 (89.5%), 10/11 (90.9%) and 27/30(90.0%) respectively. For re-staging cervical cancer, the sensitivity, specificity and accuracy of FDG PET/CT were 10/11 (90. 9%), 47/47 (100. 0%) and 57/58 (98.3%) respectively. In all, 41 had metastases. The sensitivity, specificity and accuracy of FDG PET/ CT detecting metastases were 92.7%, 88.9% and 90.9% respectively. Of the metastatic sites, 66.3% were abdominal-pelvic lymph nodes, 26.8% of the metastatic lymph nodes were detected with diameters less than 1.0 cm. Twenty-two of twenty seven (28.6%) patients were identified to have extra-pelvic lesions after PET/CT and were then changed their treatment plans. Conclusions: 18 F-FDG PET/CT is useful in staging and re-staging cervical cancer patients. PET/CT is of great value in identifying small lesions and also in detecting extra-pelvic lesions. (authors)

  9. Accuracy of preoperative diagnosis for primary hyperparathyroidism by CT, US and scintigraphy

    International Nuclear Information System (INIS)

    Imada, Masanobu; Nonaka, Satoshi; Hayashi, Tatsuya; Kunibe, Isamu; Harabuchi, Yasuaki

    2003-01-01

    We determined the usefulness of computed tomography (CT), ultrasonography (US) and Tc-Tl subtraction scintigraphy for preoperative diagnosis in 12 patients with primary hyperparathyroidism, all of which were solitary adenoma. Seven (63.6%) of 11 tumors were detected by CT, 7 (58.3%) of 12 tumors were detected by US, and 7 (63.6%) of 11 tumors were detected by Tc-Tl subtraction scintigraphy. Of 7 tumors with size>10 mm, 6 (85.7%) were detected by CT, 5 (71.4%) were detected by US, and 6 (85.7%) were detected by Tc-Tl subtraction scintigraphy, whereas only 1 (25%) with a diameter of 10 mm was detected by each of CT or Tc-Tl subtraction scintigraphy and 2 (40%) with diameters 10 mm were detected by US. Of 6 tumors situated behind the thyroid gland or intra thyroid gland, 5 (83.3%) were detected by CT and all 6 (100%) were detected by US, Tl-Tc subtraction scintigraphy, which was employed for 5 tumors, detected all 5 (100%). However, in the tumors situated beneath the thyroid gland only 2 (40%) of 5, 1 (16.7%) of 6 and 2 (33.3%) of 6 were detected by CT, US and Tc-Tl subtraction scintigraphy respectively. In 5 tumors without thyroid disease, 4 (80%) of 5 were detected by both CT and US, 3 (75%) of 4 were detected by Tc-Tl subtraction scintigraphy. However, in 7 tumors with thyroid diseases (papillary carcinoma, follicular carcinoma, follicular adenoma, chronic thyroiditis, and adenomatous goiter), 3 (50%) of 6 were detected by CT, 3 (42.9%) of 7 were detected by US and 4 (57.1%) of 7 were detected by Tc-Tl subtraction scintigraphy. Location of tumor was the factor most likely to make appropriate diagnosis difficult for primary hyperparathyroidism by any assessment method. (author)

  10. Computed tomography of liver tumors, 2. Differential diagnosis between hepatocellular carcinoma and metastatic hepatic tumor by dynamic CT scanning

    Energy Technology Data Exchange (ETDEWEB)

    Naito, Akira; Fukuoka, Haruhito; Kashiwado, Kouzou; Ichiki, Toshio; Makidono, Yoko [Hiroshima Red Cross Hospital (Japan)

    1984-02-01

    Differential diagnosis between hepatocellular carcinoma and metastatic hepatic tumor was attempted using dynamic CT scanning. Homogeneous and patchy types were peculiar to hepatocellular carcinoma, and ring-like type to metastatic hepatic tumor. However, with no enhancement, hepatocellular carcinoma could not be denied. Hepatocellular carcinoma was characterized by the enhancement shown on the early stage of dynamic CT. Ring enhancement was not visualized on dynamic CT but visualized on conventional contrast enhanced CT in hepatocellular carcinomas; it was visualized on conventional contrast enhanced CT and on dynamic CT in metastatic hepatic tumors.

  11. CT diagnosis and differential diagnosis of otodystrophic lesions of the temporal bone

    International Nuclear Information System (INIS)

    D'Archambeau, O.; Parizel, P.M.; Schepper, A.M. De; Koekelkoren, E.; Van De Heyning, P.

    1990-01-01

    The purpose of this study was to assess the diagnostic and differential diagnostic value of high-resolution computed tomography in the evaluation of temporal-bone dystrophies. The study group included 55 patients with osseous abnormalities of the temporal bone in general, and the labyrinthine capsule in particular. In 27 patients the CT scan revealed evidence of otodystrophic lesions. The CT findings in patients with otosclerosis (21 patients), osteogenesis imperfecta (two patients), fibrous dysplasia (one patient). Paget's disease (one patient) and osteoporosis (two patients) are described. The CT scans of 17 patients revealed secondary osseous lesions due to metastasis (five patients), post-inflammatory changes (10 patients) or labyrinthitis ossificans (two patients). Normal variants and congenital mineralization defects were diagnosed in nine patients, Down's syndrome in two. Our results indicate the importance of high-resolution computed tomography as the primary imaging modality in evaluating osseous lesions of the temporal bone and labyrinth. (author). 14 refs.; 13 figs; 2 tabs

  12. Systematic unenhanced CT for acute abdominal symptoms in the elderly patients improves both emergency department diagnosis and prompt clinical management

    International Nuclear Information System (INIS)

    Millet, Ingrid; Pages-Bouic, Emma; Curros-Doyon, Fernanda; Taourel, Patrice; Sebbane, Mustapha; Molinari, Nicolas; Riou, Bruno

    2017-01-01

    To assess the added-value of systematic unenhanced abdominal computed tomography (CT) on emergency department (ED) diagnosis and management accuracy compared to current practice, in elderly patients with non-traumatic acute abdominal symptoms. Institutional review board approval and informed consent were obtained. This prospective study included 401 consecutive patients 75 years of age or older, admitted to the ED with acute abdominal symptoms, and investigated by early systematic unenhanced abdominal CT scan. ED diagnosis and intended management before CT, after unenhanced CT, and after contrast CT if requested, were recorded. Diagnosis and management accuracies were evaluated and compared before CT (clinical strategy) and for two conditional strategies (current practice and systematic unenhanced CT). An expert clinical panel assigned a final diagnosis and management after a 3-month follow-up. Systematic unenhanced CT significantly improved the accurate diagnosis (76.8% to 85%, p=1.1 x 10 -6 ) and management (88.5% to 95.8%, p=2.6 x 10 -6 ) rates compared to current practice. It allowed diagnosing 30.3% of acute unsuspected pathologies, 3.4% of which were unexpected surgical procedure requirement. Systematic unenhanced abdominal CT improves ED diagnosis accuracy and appropriate management in elderly patients presenting with acute abdominal symptoms compared to current practice. (orig.)

  13. Systematic unenhanced CT for acute abdominal symptoms in the elderly patients improves both emergency department diagnosis and prompt clinical management

    Energy Technology Data Exchange (ETDEWEB)

    Millet, Ingrid; Pages-Bouic, Emma; Curros-Doyon, Fernanda; Taourel, Patrice [CHU Lapeyronie, Department of Medical Imaging, Montpellier Cedex 5 (France); Sebbane, Mustapha [Department of Emergency Medicine, CHU Lapeyronie, Montpellier (France); Molinari, Nicolas [Department of Medical Information and Statistics, CHU Montpellier (France); Riou, Bruno [GH Pitie-Salpetriere, APHP, Department of Emergency Medicine and Surgery, Paris (France)

    2017-02-15

    To assess the added-value of systematic unenhanced abdominal computed tomography (CT) on emergency department (ED) diagnosis and management accuracy compared to current practice, in elderly patients with non-traumatic acute abdominal symptoms. Institutional review board approval and informed consent were obtained. This prospective study included 401 consecutive patients 75 years of age or older, admitted to the ED with acute abdominal symptoms, and investigated by early systematic unenhanced abdominal CT scan. ED diagnosis and intended management before CT, after unenhanced CT, and after contrast CT if requested, were recorded. Diagnosis and management accuracies were evaluated and compared before CT (clinical strategy) and for two conditional strategies (current practice and systematic unenhanced CT). An expert clinical panel assigned a final diagnosis and management after a 3-month follow-up. Systematic unenhanced CT significantly improved the accurate diagnosis (76.8% to 85%, p=1.1 x 10{sup -6}) and management (88.5% to 95.8%, p=2.6 x 10{sup -6}) rates compared to current practice. It allowed diagnosing 30.3% of acute unsuspected pathologies, 3.4% of which were unexpected surgical procedure requirement. Systematic unenhanced abdominal CT improves ED diagnosis accuracy and appropriate management in elderly patients presenting with acute abdominal symptoms compared to current practice. (orig.)

  14. Generation of hybrid sinograms for the recovery of kV-CT images with metal artifacts for helical tomotherapy

    International Nuclear Information System (INIS)

    Jeon, Hosang; Park, Dahl; Kim, Wontaek; Ki, Yongkan; Kim, Yong Ho; Lee, Ju Hye; Kim, Dongwon; Youn, Hanbean; Nam, Jiho; Lee, Jayoung; Kim, Ho Kyung

    2015-01-01

    Purpose: The overall goal of this study is to restore kilovoltage computed tomography (kV-CT) images which are disfigured by patients’ metal prostheses. By generating a hybrid sinogram that is a combination of kV and megavoltage (MV) projection data, the authors suggest a novel metal artifact-reduction (MAR) method that retains the image quality to match that of kV-CT and simultaneously restores the information of metal prostheses lost due to photon starvation. Methods: CT projection data contain information about attenuation coefficients and the total length of the attenuation. By normalizing raw kV projections with their own total lengths of attenuation, mean attenuation projections were obtained. In the same manner, mean density projections of MV-CT were obtained by the normalization of MV projections resulting from the forward projection of density-calibrated MV-CT images with the geometric parameters of the kV-CT device. To generate the hybrid sinogram, metal-affected signals of the kV sinogram were identified and replaced by the corresponding signals of the MV sinogram following a density calibration step with kV data. Filtered backprojection was implemented to reconstruct the hybrid CT image. To validate the authors’ approach, they simulated four different scenarios for three heads and one pelvis using metallic rod inserts within a cylindrical phantom. Five inserts describing human body elements were also included in the phantom. The authors compared the image qualities among the kV, MV, and hybrid CT images by measuring the contrast-to-noise ratio (CNR), the signal-to-noise ratio (SNR), the densities of all inserts, and the spatial resolution. In addition, the MAR performance was compared among three existing MAR methods and the authors’ hybrid method. Finally, for clinical trials, the authors produced hybrid images of three patients having dental metal prostheses to compare their MAR performances with those of the kV, MV, and three existing MAR

  15. The limitation and coordination of CT and positron emission tomography in the diagnosis of pulmonary nodules

    International Nuclear Information System (INIS)

    Zhang Jin'e; Liang Changhong; Zhao Zhenjun; Wang Shuxia; Qiao Suixian; He Hui; Zhang Jia; Ru Guangteng

    2005-01-01

    Objective: To Analyze the limitation and coordination of CT and positron emission tomography (PET) in the diagnosis of pulmonary nodules. Methods: A retrospective study was undertaken in 118 patients with pulmonary nodules which had CT and PET scan. The interval between examinations of various imaging equipment was less than 2 weeks. The diameter of nodules ranged from 2 cm to 4 cm with an average of 2.7 cm. The nodules were proved as lung cancer by pathology in 85 cases and metastatic tumor in 2 cases, benign nodules in 31 cases, including 8 cases of tuberculosis, 6 cases of hamartoma, 6 cases of inflammatory pseudotumor, 4 cases of chronic nonspecific inflammation, 3 cases of inflammation granuloma, 2 cases of mycosis, 1 case of abscess, and 1 case of globular atelectasis. Results: 93 cases were correctly diagnosed and 25 cases were misdiagnosed with CT in 118 cases of pulmonary nodules. The misdiagnosis rate of CT was 21.2%. 12 cases of lung cancer were misdiagnosed as benign and 13 cases of benign nodules were misdiagnosed as lung cancer. 96 cases were correctly diagnosed and 22 cases were misdiagnosed with PET. The misdiagnosis rate of PET was 18.6%. 10 cases of malignant nodules were misdiagnosed as benign and 12 cases of benign nodules were misdiagnosed as lung cancer. 108 cases were correctly diagnosed and 10 cases were misdiagnosed with CT coordinated with PET. The misdiagnosis rate was 8.5%. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of CT, PET, and CT coordinated with PET were 86.2%, 58.1%, 85.2%, 60.0%, 78.8% and 88.5%, 61.3%, 86.5%, 65.5%, 81.4%, and 97.7%, 74.2%, 91.4%, 92.0%, 91.5% respectively. The accuracy showed no significant difference between CT and PET (χ 2 =0.625, P=0.239), but there were significant difference between CT coordinated with PET and CT or PET (χ 2 =7.762 and 5.318, P=0.005 and 0021). Conclusion: The features of CT and PET in benign and malignant pulmonary nodules are partly

  16. C.T. criteria of the differential diagnosis in primary retroperitoneal masses

    International Nuclear Information System (INIS)

    Pistolesi, G.F.; Procacci, C.; Caudana, R.; Bergamo Andreis, I.A.; Manera, V.; Recla, M.; Grasso, G.; Florio, C.

    1984-01-01

    This personal series of 44 primary retroperitoneal masses (P.R.P.M.) studied by C.T. is analyzed. The reliability of C.T. in the identification (44/44), characterization (43/44) and origin evaluation (41/44) of P.R.P.M. has been absolutely satisfactory. In particular, those criteria of C.T. diagnosis which may be utilized in the evaluation of the origin of upper abdominal masses are thoroughly described. The evaluation of the involvement (non invasive; invasive) of adjacent viscera has been achieved in 22/38 P.R.P.M. verified at operation. The evaluation of tumour resectability has been less reliable due to the high incidence of under-diagnosis (60% in our personal experience). C.T. may be used in addition as an aid to different diagnostic techniques (percutaneous guided needle biopsy) or to therapy (drainage of retroperitoneal abscesses). C.T. is absolutely necessary in the follow-up of P.R.P.M. after surgery, radiotherapy or chemotherapy. (orig.)

  17. New possibilities in the diagnosis of ischemia. CT-FFR and CT-Perfusion; Neue Moeglichkeiten der Ischaemiediagnostik. CT-FFR und CT-Perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Lehmkuhl, Lukas [Herz- und Gefaessklinik, Bad Neustadt an der Saale (Germany). Abt. fuer Radiologie; Krieghoff, Christian [Herzzentrum Leipzig (Germany); Gutberlet, Matthias [Herzzentrum Leipzig (Germany). Abt. fuer Diagnostische und Interventionelle Radiologie; Leipzig Univ. (Germany). Kardiologische Bildgebung

    2017-12-15

    Coronary CT-angiography (CCTA) plays an increasing role in the primary diagnostics of coronary artery disease (CAD) according to the present guidelines but also in clinical reality. The sensitivity and negative predictive value of CCTA is very high, but the specificity could still be improved. Newer techniques to assess myocardial ischemia like CT-FFR and CT-Perfusion may help to achieve that goal.

  18. FDG PET/CT imaging in the diagnosis of osteomyelitis in the diabetic foot

    Energy Technology Data Exchange (ETDEWEB)

    Kagna, Olga; Keidar, Zohar [Rambam Health Care Campus, Department of Nuclear Medicine, POB 9602, Haifa (Israel); Srour, Saher; Militianu, Daniela [Rambam Health Care Campus, Department of Diagnostic Imaging, Haifa (Israel); Melamed, Eyal [Rambam Health Care Campus, Department of Orthopedics, Haifa (Israel)

    2012-10-15

    Osteomyelitis, the most serious complication of the diabetic foot, occurs in about 20 % of patients. Early diagnosis is crucial. Appropriate treatment will avoid or decrease the likelihood of amputation. The objective of this study was to assess the value of FDG PET/CT in diabetic patients with clinically suspected osteomyelitis. Enrolled in this prospective study were 39 consecutive diabetic patients (29 men and 10 women, mean age 57 years, range 28-71 years) with 46 suspected sites of foot infection. Of these 39 patients, 38 had type 2 and 1 type 1 diabetes for 4-25 years, and 28 were receiving treatment with insulin. FDG PET/CT was interpreted for the presence, intensity (SUVmax) and localization of increased FDG foci. Final diagnosis was based on histopathology and bacteriology of surgical samples, or clinical and imaging follow-up. Osteomyelitis was correctly diagnosed in 18 and excluded in 21 sites. Of 20 lesions with focal bone FDG uptake, 2 were false-positive with no further evidence of osteomyelitis. Five sites of diffuse FDG uptake involving more than one bone on CT were correctly diagnosed as diabetic osteoarthropathy. FDG PET/CT had a sensitivity, specificity and accuracy of 100 %, 92 % and 95 % in a patient-based analysis and 100 %, 93 % and 96 % in a lesion-based analysis, respectively, for the diagnosis of osteomyelitis in the diabetic foot. FDG PET/CT was found to have high performance indices for evaluation of the diabetic foot. The PET component identified FDG-avid foci in sites of acute infection which were precisely localized on fused PET/CT images allowing correct differentiation between osteomyelitis and soft-tissue infection. (orig.)

  19. FDG PET/CT imaging in the diagnosis of osteomyelitis in the diabetic foot

    International Nuclear Information System (INIS)

    Kagna, Olga; Keidar, Zohar; Srour, Saher; Militianu, Daniela; Melamed, Eyal

    2012-01-01

    Osteomyelitis, the most serious complication of the diabetic foot, occurs in about 20 % of patients. Early diagnosis is crucial. Appropriate treatment will avoid or decrease the likelihood of amputation. The objective of this study was to assess the value of FDG PET/CT in diabetic patients with clinically suspected osteomyelitis. Enrolled in this prospective study were 39 consecutive diabetic patients (29 men and 10 women, mean age 57 years, range 28-71 years) with 46 suspected sites of foot infection. Of these 39 patients, 38 had type 2 and 1 type 1 diabetes for 4-25 years, and 28 were receiving treatment with insulin. FDG PET/CT was interpreted for the presence, intensity (SUVmax) and localization of increased FDG foci. Final diagnosis was based on histopathology and bacteriology of surgical samples, or clinical and imaging follow-up. Osteomyelitis was correctly diagnosed in 18 and excluded in 21 sites. Of 20 lesions with focal bone FDG uptake, 2 were false-positive with no further evidence of osteomyelitis. Five sites of diffuse FDG uptake involving more than one bone on CT were correctly diagnosed as diabetic osteoarthropathy. FDG PET/CT had a sensitivity, specificity and accuracy of 100 %, 92 % and 95 % in a patient-based analysis and 100 %, 93 % and 96 % in a lesion-based analysis, respectively, for the diagnosis of osteomyelitis in the diabetic foot. FDG PET/CT was found to have high performance indices for evaluation of the diabetic foot. The PET component identified FDG-avid foci in sites of acute infection which were precisely localized on fused PET/CT images allowing correct differentiation between osteomyelitis and soft-tissue infection. (orig.)

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2017-09-15

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

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

    International Nuclear Information System (INIS)

    Inoue, Taihei; Yoshida, Morikatsu; Yokoyama, Koichi; Nakaura, Takeshi; Hirata, Kenichiro; Kidoh, Masafumi; Oda, Seitaro; Utsunomiya, Daisuke; Yamashita, Yasuyuki; Harada, Kazunori

    2017-01-01

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

  2. Radiation dose reduction at a price: the effectiveness of a male gonadal shield during helical CT scans

    International Nuclear Information System (INIS)

    Dauer, Lawrence T; Casciotta, Kevin A; Erdi, Yusuf E; Rothenberg, Lawrence N

    2007-01-01

    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. The dose reduction to the gonads was measured for both direct radiation and for indirect scattered radiation from the abdomen. A 6 cm 3 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. 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. 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

  3. Radiation dose reduction at a price: the effectiveness of a male gonadal shield during helical CT scans.

    Science.gov (United States)

    Dauer, Lawrence T; Casciotta, Kevin A; Erdi, Yusuf E; Rothenberg, Lawrence N

    2007-03-16

    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. 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. 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. 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.

  4. 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.

  5. Appearance of the aging pancreas on CT scans: Implications in diagnosis of pancreatic carcinoma

    International Nuclear Information System (INIS)

    Mattison, G.R.; Francis, I.R.; Glazer, G.M.; Trenkner, S.W.

    1986-01-01

    Because early pancreatic cancer may not appear on CT as a frank mass, the CT-based diagnosis relies on detection of subtle changes such as focal loss of lobulation or asymmetry in the distribution of tissue. The author studied the normal pancreas in 140 patients of different ages to determine if there is an overlap in the appearance of the normal aging pancreas and subtle signs of pancreatic cancer. Both contour lobulation and fatty infiltration were found to increase with age and involved the pancreatic body and tail more than the head. These normal age-related changes should be recognized to avoid overdiagnosing pancreatic head masses

  6. Lung cancer screening with low-dose helical CT in Korea: experiences at the Samsung Medical Center.

    Science.gov (United States)

    Chong, Semin; Lee, Kyung Soo; Chung, Myung Jin; Kim, Tae Sung; Kim, Hojoong; Kwon, O Jung; Choi, Yoon-Ho; Rhee, Chong H

    2005-06-01

    To determine overall detection rates of lung cancer by low-dose CT (LDCT) screening and to compare histopathologic and imaging differences of detected cancers between high- and low-risk groups, this study included 6,406 asymptomatic Korean adults with >or=45 yr of age who underwent LDCT for lung cancer screening. All were classified into high- (>or=20 pack-year smoking; 3,353) and low-risk (3,053; <20 pack-yr smoking and non-smokers) groups. We compared CT findings of detected cancers and detection rates between high- and low-risk. At initial CT, 35% (2,255 of 6,406) had at least one or more non-calcified nodule. Lung cancer detection rates were 0.36% (23 of 6,406). Twenty-one non-small cell lung cancers appeared as solid (n=14) or ground-glass opacity (GGO) (n=7) nodules. Cancer likelihood was higher in GGO nodules than in solid nodules (p<0.01). Fifteen of 23 cancers occurred in high-risk group and 8 in low-risk group (p=0.215). Therefore, LDCT screening help detect early stage of lung cancer in asymptomatic Korean population with detection rate of 0.36% on a population basis and may be useful for discovering early lung cancer in low-risk group as well as in high-risk group.

  7. Diagnosis of ovarian tumors by ultrasonography and x-ray CT

    International Nuclear Information System (INIS)

    Watanabe, Hiromu

    1986-01-01

    A drawback in ultrasonography, an indispensable technique in imaging ovarian malignancies, is that it sometimes shows false positive for benign tumors including dermoid cyst and ovarian endometriosis. To overcome this, the concurrent use of X-Ray CT seems warrantable and this led us to carry out the study summarized below. CT was carried out on 268 of 322 ovarian disease cases which had undergone ultrasonography. The results obtained were as follows. Sensitivity of ultrasonography and CT in ovarian malignancies were 82 % and 88 % respectively. Of the cases subjected to both techniques, those who were deemed false positive were 39 in ultrasonography and 12 in CT. Ultrasonographic imagings of dermoid cyst and ovarian endometriosis were classified on the basis of their patterns. The results obtained revealed that those in which it was difficult to discriminate the image from ovarian malignancy were types V and VI in dermoid cyst and type III-C in ovarian endometriosis. In both dermoid cyst and ovarian endometriosis, nearly a 100 % accuracy rate was obtainable with CT for diagnosis of benign tumors. This strongly suggested that concurrent use of CT was required, in diagnosing ovarian diseases with the V or VI and III-C patterns referred to above. (author)

  8. Patent foramen ovale: diagnosis with multidetector CT--comparison with transesophageal echocardiography.

    Science.gov (United States)

    Kim, Young Jin; Hur, Jin; Shim, Chi-Young; Lee, Hye-Jeong; Ha, Jong-Won; Choe, Kyu Ok; Heo, Ji Hoe; Choi, Eui-Young; Choi, Byoung Wook

    2009-01-01

    To evaluate the clinical feasibility and accuracy of 64-section multidetector computed tomography (CT) compared with transesophageal echocardiography (TEE) for diagnosis of a patent foramen ovale (PFO). Institutional review board approval was obtained for this retrospective study. The study included 152 consecutive stroke patients (mean age, 61.7 years; 98 men, 54 women) who underwent both cardiac multidetector CT and TEE. Electrocardiographically gated cardiac CT was performed with a 64-section CT scanner by using a saline-chaser contrast agent injection technique. A contrast agent jet from the contrast agent-filled left atrium (LA) to the saline-filled right atrium (RA) and channel-like appearance of the interatrial septum (IAS) were evaluated on axial and oblique sagittal CT images. Two-dimensional and Doppler TEE were performed to detect PFO. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CT were obtained with TEE as the reference standard. A PFO was present in 26 patients at TEE. On CT images, a left-to-right contrast agent jet toward the inferior vena cava was noted in 21 patients (sensitivity, 73.1%; specificity, 98.4%; PPV, 90.5%; NPV, 94.7%). Channel-like appearance of the IAS was detected in 38 patients (sensitivity, 76.9%; specificity, 85.7%; PPV, 52.6%; NPV, 94.7%). Channel-like appearance of the IAS was noted in all patients who had a contrast agent jet. A contrast agent jet from LA to RA toward the inferior vena cava with channel-like appearance of the IAS on CT images confirms the presence of a PFO. (c) RSNA, 2008.

  9. CT diagnosis of splenic infarction in blunt trauma: imaging features, clinical significance and complications

    International Nuclear Information System (INIS)

    Miller, L.A.; Mirvis, S.E.; Shanmuganathan, K.; Ohson, A.S.

    2004-01-01

    AIM: The object of this study is to describe the appearance, complications, and outcome of segmental splenic infarctions occurring after blunt trauma using computed tomography (CT). MATERIALS AND METHODS: Thirteen blunt trauma patients were identified with splenic infarction on contrast-enhanced CT. CT images were retrospectively reviewed and the percentage of infarcted splenic tissue and presence of splenic injury separate from the site of infarction were identified. Splenic angiograms were reviewed and follow-up CT images were assessed for interval change in the appearance of the infarcts. RESULTS: The mean age of patients was 32 years and the most common mechanism of injury was road traffic accident. The majority (54%) had 25-50% infarction of the spleen. Splenic angiograms were performed in nine patients and seven demonstrated wedge-shaped regions of decreased perfusion corresponding to the infarction seen on CT with no need for intervention. Eleven patients underwent a follow-up CT that demonstrated the following: no significant change in six, near-complete resolution in two, delayed appearance of infarction in one, abscess formation in one, and delayed splenic rupture in one. CONCLUSION: Segmental splenic infarction is a rare manifestation of blunt splenic trauma. The diagnosis is readily made using contrast-enhanced CT. The majority will decrease in size on follow-up CT and resolve without clinical sequelae. Resolution of infarction is also seen and these cases are best described as temporary perfusion defects. Splenic abscess or delayed rupture are uncommon complications that may necessitate angiographic or surgical intervention

  10. CT diagnosis of splenic infarction in blunt trauma: imaging features, clinical significance and complications

    Energy Technology Data Exchange (ETDEWEB)

    Miller, L.A.; Mirvis, S.E.; Shanmuganathan, K.; Ohson, A.S. E-mail: lmiller@um.edu

    2004-04-01

    AIM: The object of this study is to describe the appearance, complications, and outcome of segmental splenic infarctions occurring after blunt trauma using computed tomography (CT). MATERIALS AND METHODS: Thirteen blunt trauma patients were identified with splenic infarction on contrast-enhanced CT. CT images were retrospectively reviewed and the percentage of infarcted splenic tissue and presence of splenic injury separate from the site of infarction were identified. Splenic angiograms were reviewed and follow-up CT images were assessed for interval change in the appearance of the infarcts. RESULTS: The mean age of patients was 32 years and the most common mechanism of injury was road traffic accident. The majority (54%) had 25-50% infarction of the spleen. Splenic angiograms were performed in nine patients and seven demonstrated wedge-shaped regions of decreased perfusion corresponding to the infarction seen on CT with no need for intervention. Eleven patients underwent a follow-up CT that demonstrated the following: no significant change in six, near-complete resolution in two, delayed appearance of infarction in one, abscess formation in one, and delayed splenic rupture in one. CONCLUSION: Segmental splenic infarction is a rare manifestation of blunt splenic trauma. The diagnosis is readily made using contrast-enhanced CT. The majority will decrease in size on follow-up CT and resolve without clinical sequelae. Resolution of infarction is also seen and these cases are best described as temporary perfusion defects. Splenic abscess or delayed rupture are uncommon complications that may necessitate angiographic or surgical intervention.

  11. 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.).

  12. CT diagnosis and differential diagnosis of otodystrophic lesions of the temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    D' Archambeau, O.; Parizel, P.M.; Schepper, A.M. De (Antwerp University Hospital (Belgium). Department of Radiology); Koekelkoren, E.; Van De Heyning, P. (Antwerp University Hospital (Belgium). Department of E.N.T.)

    The purpose of this study was to assess the diagnostic and differential diagnostic value of high-resolution computed tomography in the evaluation of temporal-bone dystrophies. The study group included 55 patients with osseous abnormalities of the temporal bone in general, and the labyrinthine capsule in particular. In 27 patients the CT scan revealed evidence of otodystrophic lesions. The CT findings in patients with otosclerosis (21 patients), osteogenesis imperfecta (two patients), fibrous dysplasia (one patient). Paget's disease (one patient) and osteoporosis (two patients) are described. The CT scans of 17 patients revealed secondary osseous lesions due to metastasis (five patients), post-inflammatory changes (10 patients) or labyrinthitis ossificans (two patients). Normal variants and congenital mineralization defects were diagnosed in nine patients, Down's syndrome in two. Our results indicate the importance of high-resolution computed tomography as the primary imaging modality in evaluating osseous lesions of the temporal bone and labyrinth. (author). 14 refs.; 13 figs; 2 tabs.

  13. An evaluation of the regional cerebral blood flow (rCBF) measurement by xenon-enhanced dynamic CT with helical scanning technique and the functional imaging by multiplanar reconstruction (MPR). Fundamental study and clinical application

    International Nuclear Information System (INIS)

    Watanabe, Kenichi

    1997-01-01

    We evaluated the quantitative rCBF by xenon-enhanced dynamic CT with helical scanning technique on all brain regions, and also examined clinical usefulness of coronal and sagittal section images which are similar to SPECT images obtained by the functional multiplanar reconstitution (MPR) imaging of many successive flow maps. We used 14 clinical cases. The conventional xenon-enhanced CT was simple and ideal method to measure rCBF, however, it had disadvantages; it gives a few laminagraphical images or only the axial directional images, compared to SPECT or PET. There is a risk to overlook lesions out of the image or not to obtain the whole images of the lesion. Although the helical scanning technique has a methodological characteristics to use adjacent data for the image reconstitution, it is by no means inferior to the conventional method in the contrast resolution or the image resolution when the co-helical function and an appropriate reconstituted function were used. It has an advantage to scan all brain regions by only one cycle of scanning. Furthermore on making good use of the property that the helical scanning technique can give the successive data, we can observe rCBF by coronal and sagittal images when many flow maps were made up by reconstituted images of the narrow steps. This shows the clinical usefulness of this technique. One of the future problem to be solved is to decrease the exposure dose. (K.H.)

  14. Comparison of MR versus CT myelography and plain CT in the diagnosis of nerve compression in acute low-back pain patients

    International Nuclear Information System (INIS)

    Thornbury, J.R.; Fryback, D.G.; Turski, P.A.; Javid, M.; McDonald, J.V.; Beinlich, B.R.

    1991-01-01

    This paper reports on how to determine if MR could replace CT-myelography or plain CT in the diagnosis of disk-caused nerve compression in patients with acute low back pain. Ninety-five outpatients were recruited from surgical and nonsurgical clinics. Each patient underwent MR (n = 95) and either CT-myelography (n = 63) or plain Ct (n = 32). Patients were followed up for 6-12 months. Fifty-six patients underwent surgical intervention, while 39 patients were treated conservatively. Retrospective blinded readings were done by using forced choice diagnoses and probability estimates. An expert panel (neurosurgeon and neurologist) determined the true diagnosis and probability of nerve compression in each case. Diagnosis was based on all record information including surgical findings (but excluding imaging results to reduce incorporation bias). Receiver operating characteristic (ROC) analysis was performed based on the blinded reading results and panel-determined true diagnoses. Subgroup analysis also will be presented

  15. Assessment of US score and CT number for diagnosis of fatty liver

    International Nuclear Information System (INIS)

    Ogasawara, Tetsuo; Tanda, Shigeru; Lim, Insu; Oota, Keisuke; Taima, Tadashi

    1987-01-01

    The author evaluates US and CT for diagnosis of fatty liver in 70 cases with fatty change of the liver. We tried to score the US findings of the fatty change, i.e., ''bright liver pattern'', ''liver-kidney contrast'', ''vascular blurring'', ''deep attenuation'', and the usefulness of the scoring was examined. Comparing with CT number, US score was more sensitive, but had no significant correlation with the amount of the fat in the liver and with the abnormality of the liver function tests. The results indicate that US should be used as a primary screening examination, and for the further evaluation of the fatty change of the liver, CT should be carried out. (author)

  16. CT differential diagnosis of primary pelvic osteosarcoma, chondrosarcoma and Ewing's sarcoma

    International Nuclear Information System (INIS)

    Heller, M.; Heyer, D.; Spielmann, R.P.; Buecheler, E.

    1990-01-01

    The value of CT for the differential diagnosis of primary malignant tumours in the pelvis was investigated in the case of three types of tumour: Osteosarcomas, chondrosarcomas and Ewing's sarcomas. A total of 78 CT examinations in 29 patients was used. The results show that CT, using suitable techniques (high resolution etc.) constitutes a valuable diagnostic method for differentiating these bone tumours. This applies not only for the localisation of the tumour and for defining its extent, but also for showing the morphology of intra- and extra-osseous soft tissue components and their patterns of calcification. It is possible to recognise patterns of growth and of tissue destruction that are typical of individual tumours. (orig.) [de

  17. Peritoneal implants without ascites. Preoperative CT diagnosis in colon carcinoma patients

    International Nuclear Information System (INIS)

    Saida, Yukihisa; Itai, Yuji; Tsunoda, Hiroko; Matsueda, Kiyoshi.

    1994-01-01

    We evaluated the preoperative CT findings in 10 patients with colon carcinoma in whom peritoneal metastases had been surgically confirmed. Seven patients lacked ascites. No CT findings suggestive of peritoneal metastasis were observed in two patients without ascites even by retrospective evaluation. A large mass was observed in the cul-de-sac in another. In the remaining four patients, small peritoneal metastases ranging from 8 to 11 mm in diameter were observed at the omentum in two, along the falciform ligament in one, and at both the omentum and the iliac fossa in one; three of these patients had received no prospective diagnosis of peritoneal metastasis prior to the surgery. In patients with advanced colon carcinoma with suspected serosal invasion, the entire peritoneal cavity should be carefully examined and interpreted using CT in order to detect small peritoneal implants even when ascites is absent. (author)

  18. The effect of CT urography in the diagnosis of non-calculous urinary obstruction diseases

    International Nuclear Information System (INIS)

    Zhang Zhuiyang; Shen Yuanliang; Li Xin; Cao Rongmei; Xu Xiqi; Dong Jian; Hua Dongying

    2004-01-01

    Objective: To evaluate the diagnostic effect of CT urography (CTU) in patients with non-calculous obstructive diseases of urinary tract. Methods: Forty cases with non-calculous urinary obstruction underwent helical CT during nephrographic and excretory phases. Three dimensional CTU was obtained with the reconstruction of excretory phase axial images through the workstation. Results: 24 of 40 cases with benign obstruction had a slight or severe urinary dilation. Among them,18 congenital urinary malformations showed specific findings. Four ureteric inflammations revealed a gradual taper of the lumen just like a beak, and another two prostatic hypertrophy appeared oval impression upon the middle of the posterior bladder. Six intrinsic and 10 extrinsic tumors were seen irregular filling defects of the urinary tracts as well as soft tissue mass surrounding the obstructive site, accompanied by the middle urinary dilation in 12 cases and severe in four. Meanwhile, bilateral ureterohydronephroses were also found in four extrinsic tumors. In six patients with unilateral nonfunctioning urinary tracts, CTU could be imaged with minimum intensity projection (MinIP) and then be merged with contralateral maximum intensity projection (MaxIP). Conclusion: CTU is an effective modality in the evaluation of non-calculous urinary obstruction diseases. (authors)

  19. CT and MRI diagnosis of chondrosarcoma in sinonasal and orbital region

    International Nuclear Information System (INIS)

    Yang Bentao; Wang Zhenchang; Xian Junfang; Zhang Zhengyu; Liu Zhonglin; Lan Baosen

    2006-01-01

    Objective: To investigate the CT and MRI findings of chondrosarcoma in sinonasal and orbital region so as to promote the diagnostic accuracy. Methods: All 12 cases of chondrosarcoma were verified by pathology. CT and MRI findings were analyzed retrospectively. Results: The lesions occurred in sinonasal cavity in 9 cases and in orbit in 3 cases. Pathologically 8 cases were conventional chondrosarcoma, 2 dedifferentiated chondrosarcoma, and 2 mesenchymal chondrosarcoma. On CT, chondrosarcoma revealed oval shape in 2 cases, lobular shape in 6 cases and irregular shape in 4 cases. The lesion showed stippled, ring, nodular, patchy or amorphous calcification. Postcontrast CT showed mild inhomogeneous enhancement in 3 cases. Chondrosarcoma demonstrated well-defined margin in 9 cases and hazy margin in 3 cases. Sinonasal chondrosarcoma revealed bony destruction in 7 cases. Orbital chondrosarcoma showed bony erosion invading ipsilateral frontal region in one case. On MR T 1 WI, conventional and dedifferentiated chondrosarcoma showed hypointense signal compared to brain in 6 cases and isointense signal in 4 cases. On T 2 WI, the lesions showed heterogeneous hyperintense signal in 8 cases and isointense signal in 2 cases with marked hypointense foci. Postcontrast MR imaging demonstrated mild to moderate inhomogeneous enhancement in these cases, and showed peripheral and septal enhancement in 5 cases of conventional chondrosarcoma, showing variegated appearance in 3 cases and honeycomb-like appearance in 2 cases. Mesenchymal chondrosarcoma showed isointense signal on both T 1 WI and T 2 WI, with homogeneous and heterogeneous enhancement in one case, respectively. MRI showed the extent and the associated changes of the lesions more clearly compared to CT. Conclusion: CT is the first modality of choice in the diagnosis of chondrosarcoma in sinonasal and orbital region. The typically peripheral and septal contrast enhancement can also suggest the diagnosis of chondrosarcoma on

  20. The application value of PET-CT in the diagnosis of breast cancer

    International Nuclear Information System (INIS)

    Li Haitao

    2005-01-01

    Breast cancer is the most common malignancy in women in most of countries. During the past decades, the application of PET with 18 f-fluoro-2-deoxy-D-glocuse ( 18 F-FDG) has remarkably improved the management of breast cancer. Nevertheless, due to anatomical localisation of 18 F-FDG uptake was difficult, the clinical interpretation of 18 F-FDG PET scan could not be exactly. A novel combined PET-CT system has largely improved the capacity of sensitivity and specificity in the diagnosis of breast cancer. In this artiacal we focus on the application value of PET-CT to breast cancer diagnosis, with respect to dissease re-staging, treatment monitoring, preoperative staging and radiotherapy planning. (authors)

  1. Analysis of main influence factors on coronary artery image quality with 64-multidetector row helical CT using a pulsating cardiac phantom

    International Nuclear Information System (INIS)

    Liu Bin; Zhao Hong; Wu Xingwang; Zhang Jiawen; Yu Yongqiang; Liao Jingmin

    2006-01-01

    Objective: To explore the main influence factors (heart rate, rotation speed, and reconstruction algorithm) on the image quality of coronary artery with 40 mm VCT (64-detector row helical CT) using a pulsating cardiac phantom. Methods: An adjustable pulsating cardiac phantom (GE) containing predetermined simulated coronary arteries was scanned using a 40 mm VCT (GE LightSpeed CT) with cardiac pulsating rates of 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 105, 110, and 115 beats per minute (bpm). The variable rotation speeds technique of 0.35 s, 0.40 s, and 0.45 s were used, respectively. The raw data were reconstructed using both one-sector and multi-sector reconstruction algorithm at optimal window of the R-R interval. The image quality score (IQS) was evaluated by two radiologi