The Relationship between Cerebral Infarction on MR and Angiographic Findings in Moyamoya Disease: Significance of the Posterior Circulation

PURPOSE: To investigate the relationship between changes in the posterior and anterior circulation, as seen at angiography, and the frequency and extent of cerebral infarction revealed by MR imaging in moyamoya disease. MATERIALS AND METHODS: This study involved 34 patients (22 females and 12 males, aged 2-52years) in whom cerebral angiography revealed the presence of moyamoya disease (bilateral: unilateral=24:10; total hemispheres=58) and who also underwent brain MR imaging. To evaluate the angiographic findings, we applied each angiographic staging system to the anterior and posterior circulation. Leptomeningeal collateral circulation from the cortical branches of the posterior cerebral artery (PCA) was also assigned one of four grades. At MR imaging, areas of cerebral cortical or subcortical infarction in the hemisphere were divided into six zones. White matter and basal ganglionic infarction, ventricular dilatation, cortical atrophy, and hemorrhagic lesions were also evaluated. To demonstrate the statistical significance of the relationship between the angiographic and the MR findings, both the Mantel-Haenszel chi-square test for trend and the chi-square test were used. RESULTS: The degree of steno-occlusive PCA change correlated significantly with the internal carotid artery (ICA) stage (p0.05). The prevalence of infarction showed significant correlation with the degree of steno-occlusive change in both the ICA and PCA. The degree of cerebral ischemia in moyamoya patients increased proportionally with the severity of PCA stenosis rather than with that of steno-occlusive lesions of the anterior circulation. Infarctions tended to be distributed in the anterior part of the hemisphere at PCA stage I or II , while in more advanced PCA lesions, they were also found posteriorly, especially in the territories of the posterior middle cerebral artery (MCA), the posterior border zone, and the PCA (p0.05). CONCLUSION: The degree of steno-occlusive lesions of the PCA correlated with the ICA stage. Progressive changes in steno-occlusive lesions of the ICA and PCA are associated with the extent and distribution of cerebral infarction. The degree of cerebral ischemia in moyamoya patients increased proportionally with the severity of PCA stenosis rather than with that of steno-occlusive lesions of the anterior circulation. In these patients, the presence of stenotic or occlusive PCA lesions appears to be significantly related to the occurrence of cerebral infarction.

A case of central pontine myelinolysis in uremic patient with peritoneal dialysis / 대한내과학회지

Central pontine myelinolysis (CPM) is a rare syndrome, especially in uremic patients undergoing dialysis. CPM induced by diabetic coma in hemodialysis patients or associated with rapid correction of hyponatremia in peritoneal dialysis patients have been reported. However, its pathogenesis has been unclear. We report a case of CPM in a 67-year-old female uremic patient undergoing continuous ambulatory peritoneal dialysis, who was admitted to our hospital for drowsy mentality. Sodium was normal (140 mEq/L) initially and throughout the entire clinical course. The fasting blood sugar level was 110 mg/dL, serum osmolality 312 mOsm/KgH2O and osmolar gap 9.47. The axial T2-weighted brain MRI showed high signal intensity in the basal pons.

Reversible Posterior Leukoencephalopathy Syndrome

PURPOSE: To review reversible posterior leukoencephalopathy syndrome. MATERIALS AND METHODS: We reviewed 22 patients (M:F=3:19; age, 17-46 years) with the characteristic clinical and imaging features of reversible posterior leukoencephalopathy syndrome. All underwent brain MRI, and in three cases both CT and MRI were performed. In one, MRA was obtained, and in eleven, follow-up MR images were obtained. We evaluated the causes of this syndrome, its clinical manifestations, and MR findings including the locations of lesions, the presence or absence of contrast enhancement, and the changes seen at follow-up MRI. RESULTS: Of the 22 patients, 13 had eclampsia (six during pregnancy and seven during puerperium). Four were receiving immunosuppressive therapy (three, cyclosporine; one, FK 506). Four suffered renal failure and one had complicated migraine. The clinical manifestations included headache (n=12), visual disturbance (n=13), seizure (n=15), focal neurologic sign (n=3), and altered mental status (n=2). Fifteen patients had hypertension and the others normotension. MRI revealed that lesions were bilateral (n=20) or unilateral (n=2). In all patients the lesion was found in the cortical and subcortical areas of the parieto-occipital lobes; other locations were the basal ganglia (n=9), posterior temporal lobe (n=8), frontal lobe (n=5), cerebellum (n=5), pons (n=2), and thalamus (n=1). All lesions were of high signal intensity on T2-weighted images, and of iso to low intensity on T1-weighted images. One was combined with acute hematoma in the left basal ganglia. In eight of 11 patients who underwent postcontrast T1-weighted MRI, there was no definite enhancement; in one, enhancement was mild, and in two, patchy. CT studies showed low attenuation, and MRA revealed mild vasospasm. The symptoms of all patients improved. Follow-up MRI in nine of 11 patients depicted complete resolution of the lesions; in two, small infarctions remained but the extent of the lesions had decreased. CONCLUSION: Reversible posterior leukoencephalopathy syndrome develops in patients with toxemia of pregnancy, renal insufficiency or complicated migraine, and those who undergo immonosuppresive therapy. The characteristic MR finding is edema in cortical or subcortical areas of the parietal and occipital lobes, without enhancement after Gd-DTPA injection. Early recognition of this readily treatable condition may obviate the need for extensive, invasive investigations, and prompt treatment can lead to a favorable prognosis.

Determination of the Activity of Pulmonary Tuberculosis: the Utility of High-Resolution Computed Tomography

PURPOSE: To evaluate the utility of high-resolution computed tomography(HRCT), as used to determine the activity of tuberculosis, and to analyze the HRCT findings in active and in inactive tuberculosis. MATERIALS AND METHODS: We analyzed the HRCT findings of 100 patients (54 men, 46 women; average age, 54 years) who according to the results of chest radiography had pulmonary tuberculosis of undetermined activity. We assessed HRCT findings such as the presence of a entrilobular, macro-, or micronodule; consolidation, ground-glass opacity, cavity, interlobular septal thickening, irregular linear opacities, bronchial wall thickening, bronchovascular bundle distortion, bronchiectasis, atelectasis, and pericicatrical emphysema. We compared the ratio of the area of nodule and consolidation to that of whole lung, and compared the findings between active and inactive tuberculosis. RESULTS: Eleven of 100 patients were excluded because the final diagnosis was other than tuberculosis. In 59 patients, the presence of active pulmonary tuberculosis was proven by positive sputum smear and/or culture for Mycobacterium tuberculosis. On the basis of the negative results of these tests, pulmonary tuberculosis was found to be inactive in 30 patients; serial chest radiographs indicated that their condition remained stable over a 6-month period. For HRCT, sensitivity was 96.6%, specificity 56.7%, positive predictive value 81.4%, negative predictive value 89.5%, and accuracy 83.1%. For active tuberculosis, the presence of centrilobular nodules, tree-in-bud, macronodules, cavity within the nodule, and consolidations was statistically significant, while for inactive tuberculosis, that of irregular linear opacities, micronodules, bronchiectasis, and cicatrization atelectasis was similarly significant. The CT score for the area of nodules and consolidations was higher in active than in inactive tuberculosis, but only the nodule score showed statistical significance. CONCLUSION: HRCT can be a useful diagnostic tool for evaluating the activity of pulmonary tuberculosis

Systemic mononuclear inflammatory vasculopathy associated with Sjogren's syndrome in a patient with primary biliary cirrhosis

We report a 46-year-old woman with primary biliary cirrhosis (PBC) presenting with Sjogren's syndrome and systemic mononuclear inflammatory vasculopathy. Biopsy specimens of sural nerve showed findings consistent with vasculitic neuropathy. Perivascular inflammatory mononuclear cell infiltration was observed on muscle biopsy specimen. The findings of abdominal computed tomography and brain magnetic resonance imaging were suggestive of vasculitis. Clinical manifestations and radiologic findings were improved after high dose prednisolone therapy.

The Usefulness of CO2 Indirect Portography in Transjugular Intrahepatic Portosystemic Shunt(TIPS)

PURPOSE: To determine the usefulness of carbon dioxide(CO2) indirect portography during TIPS procedure. MATERIALS AND METHODS: We evalvated eight patients who had undergone TIPS due to variceal hemorrhage or ascites caused by portal hypertension. All patients but one with complete situs inversus underwent wedged right hepatic venography for visualization of the portal vein using CO2. For CO2 indirect portal venography, 50cc of CO2 was injected by hand without prior injection of a small amount of CO2. In three patients a 5-F angiographic catheter was wedged into the right hepatic vein, and in the other five a 9-F sheath from a Ring 's transjugular access set was adjunctively wedged into the right hepatic vein over the 5-F catheter. The time required for portal vein puncture was defined as the time between the indirect portal venography procedure and the first procedure after successful portal vein puncture. RESULTS: All patients successfully underwent TIPS without any immediate complication. The portal vein was visualized by CO2 in 7 of 8 patients (87.5 %). Two of three patients who underwent indirect portography with only a 5-F catheter wedging demonstrated opacification of the right portal vein; in the remaining patient the portal venous system was not visualized. Of the five patients who underwent indirect portography with an adjunctive 9-F sheath wedged in the right hepatic vein, four showed opacification from the peripheral to the main portal vein, and in the other, the only right peripheral portal vein was opacified. The mean time for portal vein puncture was 20.5 minutes. CONCLUSION: For visualization of the portal venous system during TIPS procedure, the use of CO2 indirect portography is feasible.

MR Features of Bursitis around the Hip

PURPOSE: To determine the usefulness of MR imaging for differentiation between infectious and non-infectiousbursitis. MATERIALS AND METHODS: MR images of 16 patients (18 lesions) in whom bursitis around the hip had beendiagnosed were analyzed for homogeneity of the bursa, the presence of septation, the enhancement pattern, andassociated findings. Clinical data (symptoms and signs, laboratory data, aspiration of the bursa, and surgicalfindings) were available for correlation. The location of bursitis was trochanteric (n=9), ischiogluteal (n=5),iliopsoas (n=3), or ischiotrochanteric (n=1). RESULTS: Etiologies included infection in seven cases (3 pyogenic; 4tuberculous) and noninfecti-on in 11 (6 inflammation; 3 hemorrhage; 2 metabolic disease). In seven patients withinfectious bursitis, T1-weighted enhanced image revealed thick rim enhancement of the bursa (n=7) association withchanges in bone marrow signal intensity (n=2), bone erosion (n=2), and cellulitis (n=1). Of 11 cases ofnoninfectious bursitis, three demonstrated typical signal characte-ristics of hematoma within the distended bursa.In six of seven patients who underwent contrast-enh ancement, thick and thin peripheral enhancement of the bursawas noted. Bone erosion was found in one case of tuberculous bursitis and two of metab-olic disease. Internalseptation (n=4) and internal debris (n=3) were found in both infected and noninfected patients. CONCLUSION: MRimaging plays an important role in the diagnosis of bursitis around the hip. MR findings of thick rim enhancement,associated cellulitis, and changes in bone marrow signal intensity are suggestive of infectious bursitis.

CT Findings of Malignant Nasal Cavity Tumors

PURPOSE: To evaluate the CT finidngs of malignant nasal cavity tumors. MATERIALS AND METHODS: Retrospective analysis was performed on 20 patients with pathologically-proven malignant nasal cavity tumors. Using CT, we analysed their location, extent of bone destruction and of involvement of adjacent structures, and enhancing pattern. RESULTS: A total of 20 cases included nine squamous cell carcinomas, three olfactory neuroblastomas, three lymphomas, two polymorphic reticulosis, one adenoid cystic carcinoma, one undifferentiated carcinoma and one metastasis from renal cell carcinoma. All cases except one adenoid cystic carcinoma and one squamous cell carcinoma revealed bone destruction or erosion. Aggressive bone destruction and irregular enhancement were seen in eight cases of squamous cell carcinoma, seven cases of which showed involvement of the adjacent paranasal sinuses, nasopharynx, and orbit. Olfactory neuroblastomas were centered in the superior nasal cavity and the adjacent ethmoid sinus, and had erosion or destruction of the cribriform plate had occurred. Lymphomas showed bilateral involvement, with uniform contrast enhancement. Polymorphic reticuloses showed perforation or erosion of the nasal septum with bilateral involvement of the nasal cavity. CONCLUSION: The location, presence of bone destruction, involvement of adjacent structures, and enhancement pattern of tumor on CT can be helpful for the differential diagnosis of malignant nasal cavity tumors.

Sarcomatoid Transitional Cell Carcinoma in the Kidney: A Case Report

Sarcomatoid transitional cell carcinoma is a rare malignant epithelial neoplasm arising at the bladder, in which the tumor cells assume a spindle shape. This tumor accounts for approximately 0.3% of all bladder malignancies and has been reported in the renal pelvis and ureter. We encountered a case of histopathologically proven sarcomatoid transitional cell carcinoma of the left kidney in a 76-year-old male. Abdominal CT scans showed a large heterogeneous mass of solid and cystic components, with mural calcification and hematoma in the upper pole of the left kidney.

Radiological Findings of Primary Abdominal Malignant Fibrous Histiocytoma: Emphasis on CT Findings

PURPOSE: To evaluate the radiological findings of abdominal malignant fibrous histiocytomas. MATERIALS AND METHODS: We retrospectively reviewed the radiological findings of 13 masses in seven patients including two patients with multiple masses. The masses were located at the mesentery and omentum in three patients and at theretroperitoneum in four. Gastrointestinal examination using barium was performed in four patients, ultrasonographyin five and computed tomography in all. RESULTS: The average diameter of masses was 7.8cm(range : 1-20cm); plain abdominal films revealed soft tissue masses in all patients. Three of four barium studies demonstrated only displacement of bowel loops and the other showed findings of submucosal tumor. Eight of 11 masses were detected on ultrasonography and all were round or lobulated and had well defined margins. Four of these masses were greater than 8cm in diameter and showed homogeneous echogenicity with central hypo or anechoic area ; the remaining wereless than 8cm and showed relatively homogeneous echogenicity. On computed tomography, all 13 masses were seen as highly enhanced and well circumscribed. Seven were greater than 5cm in diameter and had internal low-densityareas. Peritumoral vessel-like structures were seen in eight masses and on plain abdominal radiograph and computed tomogram, calcification was seen in one patient. In no patient was combined retroperitoneal or intraperitoneal lymphadenopathy noted. CONCLUSION: Abdominal malignant fibrous histiocytomas are well-circumscribed, round orlobulated bulky masses with frequent necrosis and occasional calcification. Characteristically, there is nocombined lymphadenopathy and multiple masses are a rare manifestation. These findings may be helpful in the diagnosis of malignant fibrous histiocytoma.

CT Features of Appendiceal Mucocele

PURPOSE: To evaluate the usefulness of CT features of appendiceal mucocele in the diagnosis and evaluation of complications. MATERIALS AND METHODS: We retrospectively reviewed CT findings and compared with operative findings in 7 cases of pathologically proven appendiceal mucocele. CT findings such as location and extent of the lesion, Issue density, thickness or calcification of the wall, presence of adjacent inflammatory infiltration, and visualization of normal vermiform appendix were analyzed. RESULTS: Appendiceal mucocele was found as homogeneous low density cystic mass adjacent to the cecum, which has no surrounding inflammatory infiltration except in one case of perforation and one case of intussusception. Mean CT number measured in 4 cases was 21 Hounsfield unit. Thin curvilinear calcifications were noted along the cystic wall in 2 cases. Normal vermiform appendix couldn't be demonstrated in all cases. CONCLUSION: Appendiceal mucocele is characterized by homogeneously low density and thin walled cystic tumor adjacent to cecum without surrounding inflammatory infiltration, and absence of normal vermiform appendix on CT. Therefore, CT is valuable in preventing operative complications of appendiceal mucocele.