Results 1 - 10 of 4969
Results 1 - 10 of 4969. Search took: 0.024 seconds
|Sort by: date | relevance|
[en] Intrathoracic extramedullary hematopoiesis (EMH) is a rare condition of the hereditary spherocytosis. EMH usually regresses or disappears after treatment; such as splenectomy in the case of spherocytosis. We report a case of hereditary spherocytosis. It is presented with an unilateral paravertebral posterior mediastinal mass. After splenectomy, it revealed shrinkage and fatty replacement on serial CT scans.
[en] To determine the most useful findings of gadoxetic acid-enhanced 3.0 Tesla (T) MRI for differentiating focal eosinophilic infiltration (FEI) from hepatic metastasis with verification of their usefulness. Pathologically or clinically proven 39 FEIs from 25 patients and 79 hepatic metastases from 51 patients were included in the study. Gadoxetic acid-enhanced 3.0T MRI was performed in all cancer patients. Size differences measured between T2-weighted and hepatobiliary-phase images for lesions > 1 cm and morphologic findings (margin, shape, signal intensity on T1- and T2-weighted images, enhancement pattern on dynamic images, and target appearance on hepatobiliary-phase images) were compared between two groups via Student's t test as well as univariate and multivariate analyses. Diagnostic predictive values of two observers for differentiating two groups were assessed before (session 1) and after (session 2) recognition of results. Mean size difference (2.1 mm) in FEIs between the two images was significantly greater than for metastases (0.7 mm) (p < 0.05). An ill-defined margin and isointensity on T1-weighted images were independently significant morphologic findings (p < 0.05) for differentiating the two groups. All observers achieved a higher diagnostic accuracy in session 2 (97% and 98%) than session 1 (92% and 89%) with statistical significance in observer 2 (p < 0.05). All observers had significantly higher sensitivities (95%) and negative predictive values (NPVs) (98%) in session 2 than in session 1 (sensitivity, 74% in two observers; NPV, 89% and 88%) (p < 0.05). With the size change, an ill-defined margin and isointensity on T1-weighted images are the most useful findings for differentiating FEI from hepatic metastasis on gadoxetic acid-enhanced 3.0T MRI.
[en] We report here on a case of localized lymphoid hyperplasia of the pancreas in a 70-year-old man which manifested as double lesions (uncinate process and tail) in the organ. The lesions were incidentally detected as hypoechoic lesions on ultrasonography and they appeared as delayed enhancing lesions on the contrast-enhanced dynamic CT and MRI. Total pancreatectomy was performed, because malignant tumor could not be excluded according to the preoperative imaging studies and the endoscopic ultrasound-guided biopsy failed. Pathology revealed localized lymphoid hyperplasia. The patient had an uneventful postoperative course. He has been alive for 18 months after surgery.
[en] Prostatic stromal sarcoma (PSS) is quite rare. Herein, we describe magnetic resonance imaging (MRI) features of a PSS identified in a 26-year-old man with dysuria and hematuria. MRI clearly depicted the extent and multinodular appearance of the tumor, which was mainly located in the central zone of the prostate. The tumor appeared as a heterogeneously signal-hyperintense mass with a pseudocapsule on T2-weighted imaging. Contrast-enhanced T1-weighted MRI showed necrotic portions in the gradually enhanced solid mass, and diffusion-weighted imaging permitted the accurate assessment of the local extent of the tumor. Thus, the appearance on MRI was quite different from that of adenocarcinoma of the prostate.
[en] We report here on a rare case of primary AL hepatic amyloidosis associated with multiple myeloma in a 64-year-old woman. The patient was referred for evaluating her progressive jaundice and right upper quadrant pain. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) showed diffusely and markedly increased 18F-FDG uptake in the liver. Although there have been several case studies showing positive 18F-FDG uptake in pulmonary amyloidosis, to the best of our knowledge, the 18F-FDG PET/CT findings of hepatic amyloidosis or primary hepatic amyloidosis associated with multiple myeloma have not been reported previously.
[en] We wanted to differentiate between transient ischemic attack (TIA) and minor stroke using fractional anisotropy and three-dimensional (3D) fiber tractography. The clinical data, conventional magnetic resonance imaging (MRI), diffusion weighted imaging (DWI) and diffusion tensor imaging (DTI) were obtained for 45 TIA patients and 33 minor stroke patients. The fractional anisotrophy ratio (rFA) between the lesion and the mirrored corresponding contralateral normal tissue was calculated and analyzed. The spatial relationship between the lesion and the corticospinal tract (CST) was analyzed and the lesion sizes in the minor stroke patients and TIA patients were compared. Twenty-two of the 45 TIA patients (49%) revealed focal abnormalities following DWI. The rFA was significantly lower (p < 0.05) in the stroke patients (0.71 ± 0.29) compared to that of the TIA patients (1.05 ± 0.37). The CST was involved in almost all stroke lesions, but it was not involved in 68% of the TIA lesions. The TIA patients had significantly lower CST injury scores (3.25 ± 1.75) than did the stroke patients (8.80 ± 2.39) (p = 0.004). Our data indicate that TIA and minor stroke can be identified by analyzing the rFA and the degree of CST involvement, and this may also allow more accurate prediction of a patient's long-term recovery or disability.
[en] A cerebral air embolism is a rare cause of stroke, but may occur in patients undergoing invasive cardiac and pulmonary procedures, as well as in divers suffering pulmonary barotrauma from rapid ascent. A cerebral air embolism due to other causes, especially a change of air pressure from air travel, is particularly rare. Here, we report a case of cerebraenr embolism during commercial air travel in a patient with an tuberculous-destroyed lung.
[en] To compare radiation doses of dual-energy CT (DECT) to single-energy CT (SECT) by a phantom experiment, with the application of mean tube currents for abdomino-pelvic CT. This study includes patients who were examined by contrast-enhanced CT for kidney evaluation. We divided the patients into six groups according to sex and body mass index. Each group consisted of five patients and a total of 30 patients were evaluated. We split the body parts (abdomen and pelvis), and calculated the mean tube current of each group as well as investigated the image noise. Applying the mean mAs from a CT scan, we measured the weighted CT dose index (CTDIw) of DECT and SECT. We compared the measured CTDIw to an estimated CTDI value displayed on the CT console. We also compared the radiation dose ratio of DECT to SECT (D/S ratio) for each subgroup. The radiation doses were compared by the student's t-test and analysis of variance. The difference of image noise between DECT and SECT was not statistically significant. Radiation dose of DECT was higher than SECT by about 21.6% (10.69 mGy, 8.79 mGy; p < 0.0001), and the measured CTDI of the DECT was significantly higher than the estimated CTDI by about 6% (p < 0.001). The D/S ratio was not significant between the six groups. The measured CTDIw of abdominopelvic DECT studies were significantly higher than those of SECT.
[en] Pericoccygeal epidermoid cyst is a rare benign congenital lesion lined with keratinized squamous epithelium. We report the magnetic resonance imaging findings of an epidermoid cyst at the precoccygeal tip as a cause of coccygodynia in a 32-year-old woman and a retrococcygeal epidermoid cyst in a 27-year-old man. We also describe the pericoccygeal lesions and coccygodynia.
[en] Neurocutaneous melanosis is a rare disorder characterized by the presence of a large or multiple congenital melanocytic nevus with proliferation of melanocytes in the central nervous system. The prognosis of neurocutaneous melanosis is extremely poor and its diagnostic approach requires understanding its brain magnetic resonance imaging findings. We report a patient with asymptomatic neurocutaneous melanosis and its radiologic findings.