Computerized radiology : official journal of the Computerized Tomography Society最新文献

Congenitally-corrected transposition of the great vessels (CTGV) may be detected de novo in adulthood and the plain radiographic findings may be ambiguous or they may be mimicked by a mediastinal mass. CT readily shows the malposition of the aorta and pulmonary artery, and may also show associated congenital heart lesions. The following cases demonstrate the CT findings in CTGV and the distinction of CTGV from conditions resembling it on radiographs.

Misinterpretation of CT scans in the skull base can result from artifacts due to abrupt density variations of anatomical structure. In this report a wide dorsum sella with low attenuation medullary cavity was initially mistaken on axial scans for an enhancing suprasellar mass. The correct diagnosis was made with follow-up scans based upon thinner cuts, slice angulation negative to the baseline, and reconstructed coronal and sagittal images,

Seven cases of surgically proven intraspinal synovial cysts are reported. Computed tomographic (CT) scans demonstrated a series of low-density masses adjacent to the facet joints; in three cases, a dense rim indicated a calcified wall on the cyst; in one, the wall was partially calcified; and in three the mass appeared to be filled with gas. In all of these cases, there was severe degenerative facet disease at the same level as the synovial cyst. In six patients, the cysts were unilateral, while one was bilateral; seven cysts were located at the level of L4–L5, and one at L3-L4. We conclude from this study that the intraspinal synovial cyst can be identified reliably by the CT scan.

Nine cases of Meckel diverticulum presenting with intussusception were reviewed and correlated clinically, radiologically and pathologically. The appearance of intussuscepted Meckel diverticulum by small bowel series is not specific. However, by CT, a central fat density surrounded by a thick collar of soft tissue was noted in one case correlating well with the gross pathologic appearance. The pathologic material in all our cases suggests that this CT appearance is characteristic of an inverted Meckel diverticulum.

Low attenuation areas were seen at CT in the basal ganglia of 23 patients aged less than 15 years. The relationship between CT images and pathological findings is investigated and the differential diagnosis is made.

We report a case of right psoas abscess resulting from a carcinoma of the ascending colon. Abdominal CT examination suggested a preoperative diagnosis of neoplasm of the colon, which was confirmed on barium enema films and at surgical operation.

A retrospective study was done of the MRI and CT scans of 267 consecutive patients sent for an evaluation of one or more seizures. 21% ($\text{57}\text{267}$) of the MRI scans were abnormal. The CT scan was normal in 28% of these MRI documented abnormal cases. In an additional 10% of these cases, MRI was more specific than CT scan. CT was more specific in cases of calcification and abscess (7%). There was one case of undetermined pathology in which CT was abnormal despite a normal MRI. The predominant abnormalities found on MRI included tumor, infarction and vascular malformation. MRI is more sensitive than CT in noting central nervous system pathology and lesions of potential therapeutic significance in patients with seizures.

A case of a pseudomeningocele following anterior spinal fusion for tuberculous disease of the spine, and presenting as a large abdominal cystic mass is documented in view of the rarity of the presentation, the anterior location and the size of the pseudomeningocele.

Intracranial dermoid tumors have characteristic MR and CT appearances. Rupture of an intracranial dermoid produces a dramatic MR and CT appearance. Two cases of ruptured intracranial dermoid tumors are presented, one with rupture into the subarachnoid space, another with rupture into the ventricles. MR and CT findings are included.