Staging of early endometrial carcinoma: assessment with T2-weighted and gadolinium-enhanced T1-weighted MR imaging.

This study evaluated the usefulness of T2-weighted and gadolinium-enhanced T1-weighted magnetic resonance (MR) images correlated with patients' menopausal status in assessing the depth of myometrial invasion in stage I endometrial carcinoma. MR images of 46 patients with stage I endometrial carcinoma were retrospectively reviewed. Twenty-five patients were premenopausal, and 21 were postmenopausal. The staging accuracy without regard to menopausal status was 59% for T2-weighted images and 61% for gadolinium-enhanced T1-weighted images. However, when staging accuracy was evaluated separately in the premenopausal and postmenopausal patient groups, T2-weighted imaging had an accuracy of 80% in the premenopausal group and gadolinium-enhanced T1-weighted imaging had an accuracy of 81% in the postmenopausal group. Therefore, T2-weighted imaging was more accurate in premenopausal patients and gadolinium-enhanced T1-weighted imaging was more accurate in postmenopausal patients. The overall accuracy of staging with MR imaging improved to 80% when patients' menopausal status was considered. Therefore, menopausal status should be considered when T2-weighted and gadolinium-enhanced T1-weighted MR images are used to stage early endometrial carcinoma.

CT features of systemic lupus erythematosus in patients with acute abdominal pain: emphasis on ischemic bowel disease.

PURPOSE: To evaluate the computed tomographic (CT) features of systemic lupus erythematosus (SLE) in patients with acute abdominal pain. Special emphasis was placed on the analysis of ischemic bowel disease. MATERIALS AND METHODS: The authors retrospectively reviewed the images from 39 abdominal CT examinations performed in 33 patients with SLE and acute abdominal pain. Images were evaluated for bowel wall changes, mesenteric changes, fluid collection, retroperitoneal lymphadenopathy, peritoneal enhancement, and hepatomegaly as well as for changes in other abdominal organs. Ischemic bowel disease was diagnosed if at least three of the following signs were seen: bowel wall thickening, target sign, dilatation of intestinal segments, engorgement of mesenteric vessels, and increased attenuation of mesenteric fat. RESULTS: Thirty-one (79%) of the 39 examinations had CT findings diagnostic of ischemic bowel disease, including symmetric bowel wall thickening (n = 29), target sign (n = 26), and mesenteric vascular engorgement and haziness (n = 31). In 24 cases, bowel wall thickening was multifocal, with variable length, and did not appear to be confined to a single vascular territory. CONCLUSION: The most common CT finding in patients with SLE and acute abdominal pain is ischemic bowel disease. CT is useful for detecting the primary cause of gastrointestinal symptoms, planning treatment, and monitoring for infarction or perforation.

Benign solitary fibrous tumour of the pre-sacral space: MRI findings.

Benign solitary fibrous tumour, a rare mesenchymal tumour of adults, usually arises from the pleura. Only a few cases have been reported in the retroperitoneum and, to our knowledge, there has been no report of its imaging features. We describe the MRI features of benign solitary fibrous tumour arising from the pre-sacral space.

Pneumothorax size: correlation of supine anteroposterior with erect posteroanterior chest radiographs.

Findings in 30 consecutive patients with pneumothorax were prospectively analyzed. All patients underwent supine anteroposterior (AP) and erect posteroanterior (PA) chest radiography. The interpleural distances were measured at three locations. Average interpleural distances on supine AP and erect PA radiographs were analyzed by means of correlation and linear regression analysis. The authors developed a formula that can be used to estimate the size of a pneumothorax on a supine AP chest radiograph.

Nonossifying fibroma: characteristics at MR imaging with pathologic correlation.

PURPOSE: To correlate the findings of nonossifying fibroma at magnetic resonance (MR) imaging with those at pathologic examination. MATERIALS AND METHODS: In 19 patients (age range, 8-25 years; mean age, 14 years) with pathologically proved nonossifying fibroma, MR images were analyzed for signal intensity and patterns of contrast enhancement. Findings at MR imaging and biopsy were correlated. RESULTS: On T1-weighted images, all nonossifying fibromas had low signal intensity compared with that of skeletal muscle. On T2-weighted images, 15 lesions (79%) were hypointense and four (21%) were hyperintense. On gadolinium-enhanced images, intense contrast enhancement was seen throughout 15 lesions (heterogeneous pattern in 12 and homogeneous in three) and in the margins and septa in four. Extensive hypercellular fibrous tissue and hemosiderin seen at pathologic examination were depicted with low signal intensity on T2-weighted MR images. CONCLUSION: The distinguishing features of nonossifying fibroma included hypointensity and septation on T2-weighted images. Signal intensity on T1- and T2-weighted MR images and the patterns of contrast enhancement were dependent on the amounts of hypercellular fibrous tissue, hemosiderin, hemorrhage, collagen, foamy histiocytes, and bone trabeculae.

Neuronal laterality in Parkinson's disease with unilateral symptom by in vivo 1H magnetic resonance spectroscopy.

RATIONALE AND OBJECTIVES: The authors investigate whether there is a lateral effect of 1H-magnetic resonance spectroscopy (MRS) observable metabolite ratios between the symptomatic and the asymptomatic side in Parkinson's disease with unilateral symptoms. METHODS: Localized in vivo 1H MRS was used to measure the metabolite levels in the symptomatic and the asymptomatic sides of the substantia nigra (SN) and putamen-globus pallidus (PG) in Parkinson's disease with unilateral symptom (n = 15). The metabolite ratios of N-acetylasparatate (NAA)/creatine (Cr), and choline-containing compounds (Cho)/Cr in the symptomatic side were compared with those in the asymptomatic side. According to the symptomatic duration, the authors evaluated whether there was a specific correlation between laterality and the clinical stage. RESULTS: Significant metabolic lateral effect of NAA/Cr ratio was established between the symptomatic and the asymptomatic sides of SN and PG in Parkinson's disease with unilateral symptoms (P = 0.03). The decreased NAA/Cr ratio was calculated in at least one of the selected regions in SN and PG, indicating neuronal loss. The main observations were that NAA/Cr ratios were reduced in the left symptomatic side (n = 7; P = 0.001) and reduced to a lesser degree in the right symptomatic side (n = 8; P = 0.03 [PG], P = 0.21 [SN]) and that there was no significant laterality of other metabolite ratios. CONCLUSIONS: On the basis of NAA/Cr ratios between the symptomatic and the asymptomatic sides, the present 1H MRS study shows a significant neuronal laterality in Parkinson's disease with unilateral symptoms. In vivo 1H MRS may provide a diagnostic marker for neuronal dysfunction in Parkinson's disease with unilateral symptoms.

Pulmonary nodules: CT-guided contrast material localization for thoracoscopic resection.

Fifteen patients underwent computed tomography (CT)-guided contrast material localization of pulmonary nodules, with barium and indigo carmine stain used in five patients, iodized oil and indigo carmine stain in five, and water-soluble contrast material and indigo carmine stain in five before fluoroscopy-assisted thoracoscopic resection. Contrast material localization was successful in all cases, and the surgeon confirmed accurate localization, CT-guided contrast material localization is simple and useful for thoracoscopic resection.

Clinical results of 24 pituitary macroadenomas with linac-based stereotactic radiosurgery.

PURPOSE: To determine the impact of stereotactic radiosurgery (SRS) on the clinical course, hormonal status, and follow-up CT/MRI scan of pituitary macroadenomas. METHODS AND MATERIALS: From July 1988 to March 1996, 24 pituitary macroadenomas had been treated using 6 MV linear accelerator based SRS. They consisted of 11 (45.8%) prolactinomas, 2 (8.3%) growth hormone (GH)-secreting tumors, 1 (4.2%) Cushing's disease, 8 (33.3%) nonsecreting (nonfunctioning: NF) tumors, and 2 (8.3%) mixed prolactin-growth hormone (PRL-GH)-secreting tumors (M:F = 12:12; aged 21-61 years). Postoperative irradiation was performed in all cases except for the instance of Cushing's disease. The prescribed dose to tumor center varied from 10 to 27 Gy (mean 21.1 Gy) using a collimator size of 0.5 to 2.5 cm. The follow-up duration ranged from 13 to 89 months (mean 49.2 months). Results from these patients were compared to our results using conventional radiation. RESULTS: Visual acuity and field defect were improved or became normal in 19 (79.2%) cases. Four (16.7%) remained unchanged after the treatment. One (4.1%) progressed 6 years after SRS and subsequently had repeat surgery with conventional boost irradiation. Of the 13 (46.4%) prolactinomas, including two mixed PRL-GH secreting tumors, 11 (84.1%) revealed normal hormonal levels within 1 year after SRS. In contrast, it took 2 years to become normal after conventional radiation therapy. In four GH-secreting tumors including two mixed PRL-GH secreting tumors, SRS and conventional methods showed similar responses. On follow-up imagings of the 21 patients, the mass was completely resolved in 4 (16.7%), including 3 PRLs and one NF, decreased in 11 (45.8%), and unchanged in 5 (16.7%) with central necrosis or cysts. One (4.2%) progressed and was reoperated 6 years after treatment. The complications related to SRS were comparable to those from conventional method. CONCLUSION: Radiosurgery can be used effectively in patients with pituitary adenoma. In this study, a more rapid hormonal and clinical response was achieved with radiosurgery than with conventional pituitary irradiation treatment.

Evaluation of the effects of high dose irradiation on canine thigh muscle by follow-up magnetic resonance imaging and phosphorus-31 magnetic resonance spectroscopy.

RATIONALE AND OBJECTIVES: The authors investigate alterations of proton T1 and T2 relaxation times and phosphorus metabolites of canine thigh muscle tissue after high dose x-ray irradiation by follow-up magnetic resonance imaging (MRI) and phosphorus-31 (31P) magnetic resonance spectroscopy (MRS). METHODS: A group of 20 dogs was used for MRI and in vivo 31P MRS. Single doses of 5,000 and 10,000 cGy were delivered to the right thigh muscle of groups of 10 dogs each. All MRI and 31P MRS examinations were performed before irradiation and 1, 7, 14, 28, 42, and 56 days after irradiation. For measurement of T1, repetition time (TR) was measured at 300, 500, 1000, 1500, 2000 msec and echo time (TE) was fixed at 12 msec. Also, for measurement of T2, TE was measured at 20, 40, 60, and 80 msec and TR was fixed at 2000 msec. Image selected in vivo spectroscopy (ISIS) pulse sequence was used to obtain 31P MR spectra. Peak areas for each phosphorus metabolite were measured using a Marquart algorithm. RESULTS: Magnetic resonance imaging signal began to change at 28 days after a single dose of 10,000 cGy, whereas there was no significant MRI signal change until 56 days after a single dose of 5,000 cGy. Also, extensive MRI signal changes were observed at 42 days after a single dose of 10,000 cGy. Significant correlation was established between T2 and a lapse of time although there was no correlation between T1 and a lapse of time. T2 value increased substantially corresponding to the time period after x-ray irradiation. Although MR spectral change was not observed until 42 days after a single dose of 5,000 cGy, it began at 14 days after a single dose of 10,000 cGy. And, significant MR spectral changes were observed at 28 and 42 days. Inorganic phosphate and phosphodiesters signal intensities increased while phosphocreatine signal intensity decreased. The pH value was 7.22 +/- 0.05 at control, and 6.98 +/- 0.04 at 42 days after a single dose of 10,000 cGy. CONCLUSIONS: The postirradiation follow-up MRI and 31P MRS studies demonstrated that morphologic and metabolic changes were dependent upon the x-ray dose and a lapse of time.

Recurrent parosteal osteosarcoma of the talus in a 2-year-old child.

Parosteal osteosarcoma is an uncommon, low-grade malignant bone tumor and is found in an older age group than conventional osteosarcoma. We present a talar parosteal osteosarcoma that recurred twice in a 2-year-old child. To our knowledge, this is the youngest patient reported with a parosteal osteosarcoma. The talus is an unusual site for parosteal osteosarcoma. Inadequate resection due to a diagnosis of juxtacortical chondroma resulted in recurrence of the tumor. The age of the patient, the thick cartilaginous cap, and well-differentiated trabecular bone all contributed to the critical erroneous diagnosis.

Gastrointestinal leiomyoma and leiomyosarcoma: CT differentiation.

PURPOSE: Our goal was to evaluate CT efficacy in differentiating gastrointestinal leiomyoma and leiomyosarcoma. METHOD: We retrospectively reviewed CT scans of 45 patients (21 men, 24 women, mean age 55 years) with surgically proven gastrointestinal leiomyomas (n = 21) and leiomyosarcomas (n = 24) with respect to size, contour, enhancing pattern, mesenteric fat infiltration, calcification, ulceration, regional lymphadenopathy, direct invasion, distant metastasis, and growth pattern after visual inspection by two radiologists in agreement. On the basis of these CT features, subjective diagnosis was also categorized into three groups (Group I: probably benign, Group II: probably malignant, Group III: diagnostic malignant). The results were compared with the final histopathologic diagnosis. RESULTS: In addition to the features of direct invasion and distant metastasis suggesting diagnostic malignancy, the CT features favoring malignancy with statistical significance included larger size (> 5 cm), lobulated contour, heterogeneous enhancement, mesenteric fat infiltration, ulceration, regional lymphadenopathy, and exophytic growth pattern (p < 0.005). However, calcification was not significant in differentiating the two entities (p = 0.25163). A subjective analysis revealed 89% sensitivity, 85% specificity, and 87% accuracy for diagnosis of leiomyosarcoma. CONCLUSION: CT features are useful in differentiating leiomyoma and leiomyosarcoma in gastrointestinal tract.

Resistive index of the intrascrotal artery in scrotal inflammatory disease.

PURPOSE: To investigate the utility of the resistive indices (RIs) of the epididymal and intratesticular arteries, and to establish diagnostic criteria for scrotal inflammatory disease on the basis of quantitative color Doppler sonography. MATERIAL AND METHODS: We prospectively examined 29 consecutive patients with scrotal pain, and 15 normal control subjects. The RIs of the intratesticular and epididymal arteries were obtained from color Doppler sonographs. RESULTS: The RIs of the testicular artery in epididymoorchitis were significantly lower than those in normal control subjects and in epididymitis (p < 0.01) while the RIs of the testicular artery in epididymitis and control subjects were similar (p > 0.5). With a cut-off value of RI = 0.5, sensitivity, specificity, accuracy, and positive and negative predictive values were 91%, 94%, 94%, 83%, and 77% respectively. The mean RI of the epididymal arteries in epididymitis and epididymoorchitis was 0.49 +/- 0.11. A high level of diagnostic accuracy in scrotal inflammatory disease was achieved when the RIs of the intratesticular and epididymal arteries were less than 0.5 and 0.7 respectively. CONCLUSION: The RI of the intrascrotal artery would give a more objective evaluation than subjective assessment and could provide diagnostic criteria for scrotal inflammatory disease.

Blunt traumatic rupture of the diaphragm: sonographic diagnosis.

Ultrasonographic features of seven patients with diaphragmatic rupture due to blunt trauma were analyzed. The ruptures occurred at the left hemidiaphragm in four patients and at the right in three. Direct ultrasonographic findings were as follows: disrupted diaphragm in four patients; nonvisualized diaphragm in three patients; floating diaphragm in two patients; and herniation of the liver or bowel loops through the diaphragmatic defect in three patients. Indirect sonographic findings included pleural effusion or subphrenic fluid collection in five patients and splenic laceration in one. Although the number of patients was limited, ultrasonography was very useful for the diagnosis of diaphragmatic rupture.

Xanthogranulomatous cholecystitis: CT features with emphasis on differentiation from gallbladder carcinoma.

PURPOSE: To evaluate the computed tomographic (CT) features of xanthogranulomatous cholecystitis (XGC) and to distinguish it from gallbladder carcinoma. MATERIALS AND METHODS: Retrospective analysis was performed in 11 patients with XGC and 17 patients with gallbladder carcinoma in which the wall was thickened. The following CT features were analyzed: maximum wall thickness, intramural hypoattenuated nodules, mucosal line, patterns of wall thickening and enhancement, and the presence of stones. The changes outside the gallbladder were also compared. RESULTS: The mean thickness of the gallbladder wall was 1.8 cm in patients with XGC and 2.1 cm in patients with gallbladder carcinoma. Intramural hypoattenuated nodules were seen in all patients with XGC but in only seven patients with gallbladder carcinoma (P = .008). The mucosal line was observed in nine patients with XGC and in six with gallbladder carcinoma (P = .02). The gallbladder wall was more diffusely thickened in patients with XGC (10 of 11 patients) than in patients with gallbladder carcinoma (seven of 17 patients) (P = .01). The occurrence of changes outside the gallbladder did not differ statistically significantly. CONCLUSION: Because of a statistically significant overlap of CT features, only when intramural hypoattenuated nodules occupy a large area of the thickened gallbladder wall can the diagnosis of XGC be highly suggestive. The diagnosis of XGC at CT may indicate a less aggressive surgical approach.

Eosinophilic cholangitis: US, CT, and cholangiography findings.

We report a case of eosinophilic cholangitis, with US, CT, and cholangiographic findings. The lesion showed marked wall thickening of cystic and common bile ducts on US and CT together with mild diffuse narrowing of the common duct on cholangiography.

Fibrous dysplasia: MR imaging characteristics with radiopathologic correlation.

OBJECTIVE: The purpose of this study was to describe the findings of MR imaging of fibrous dysplasia and to evaluate the correlation between radiologic and pathologic findings. MATERIALS AND METHODS: MR images of 13 proven cases of fibrous dysplasia were analyzed for signal intensity, hypointense rind, internal septations, cystic changes, soft-tissue extension, and patterns of contrast enhancement. RESULTS: All cases of fibrous dysplasia showed low signal intensity on T1-weighted MR images. Five cases (38%) were hypointense on T2-weighted MR images, and the other eight cases (62%) were hyperintense. Hypointense rind was seen in 10 cases (77%); internal septations were seen in three cases (23%); and cystic changes was seen in two cases (15%). Soft-tissue extension was observed in four cases (31%), including one case (8%) with a pathologic fracture. After gadolinium infusion, central contrast enhancement was noted in eight cases (73%), and peripheral rim enhancement was noted in three cases (27%). Numerous bony trabeculae, confirmed pathologically, caused a hypointense signal intensity on T2-weighted images. CONCLUSION: Patients with fibrous dysplasia showed a correlation between radiologic and pathologic findings. Our results showed that T1-weighted images reveal fibrous dysplasia as hypointense, and T2-weighted images reveal fibrous dysplasia as either hyperintense or hypointense. Signal intensity on T1- and T2-weighted images and the degree of contrast enhancement on T1-weighted images depended on the amount and degree of bony trabeculae, cellularity, collagen, and cystic and hemorrhagic changes.

Idiopathic transverse myelitis: MR characteristics.

PURPOSE: To describe the MR characteristics that can distinguish idiopathic transverse myelitis from other intramedullary lesions. METHODS: A total of 32 initial and follow-up MR studies in 17 patients with clinically proved transverse myelitis were reviewed retrospectively. The location, size, pattern, and segmental length of areas of hyperintensity were estimated on T2-weighted axial and sagittal images. In 15 of the patients, whose neurologic abnormalities were limited to the spinal cord, the location and pattern of intramedullary contrast enhancement were evaluated on sagittal and axial T1-weighted images. Follow-up MR studies were available for 10 patients. The statistical significance of cord enhancement between the groups with and without cord expansion was calculated. RESULTS: Common MR findings of idiopathic transverse myelitis included a centrally located hyperintensity occupying more than two thirds of the cross-sectional area of the cord (88%); a length of 3 to 4 vertebral segments (53%), with variable presence of cord expansion (47%); a small central area of intensity, isointense with normal cord, in the core of hyperintensity (47%); focal, peripheral cord enhancement (53%), particularly in patients with cord expansion; and a slow regression of T2 hyperintensity with an enhancing nodule. Although no linear correspondence was observed between MR findings and neurologic signs and symptoms, all but 4 patients improved clinically as MR findings improved or remained stable. CONCLUSIONS: MR findings are helpful in detecting transverse myelitis and in differentiating this entity from multiple sclerosis and cord tumors, but clinical assessment and observation of MR changes over time are essential in making the diagnosis.

Adrenal paragonimiasis simulating adrenal tumor--a case report.

We describe a case of adrenal paragonimiasis with its computed tomographic and ultrasonographic findings. Computed tomogram showed a well enhancing oval mass at right adrenal gland and ultrasonogram showed a dumbbell-shaped hyperechoic mass saddling on the top of the right kidney. Surgical specimen was multicystic mass filled with creamy material.

Observation of metabolic changes in chronic schizophrenia after neuroleptic treatment by in vivo hydrogen magnetic resonance spectroscopy.

RATIONALE AND OBJECTIVES: The authors investigate: (1) whether there is a lateral effect of hydrogen (1H) magnetic resonance (MR) spectroscopy observable metabolite ratios between the right and the left prefrontal lobe in chronic schizophrenia; (2) whether there is a change of proton metabolite ratios in chronic schizophrenia after neuroleptic treatment; (3) whether there is a relation between changes in 1H MR spectra and the clinical assessment of Brief Psychiatric Rating Scale (BPRS); and (4) to investigate a hypofrontality hypothesis in schizophrenia in terms of neurochemical aspects. METHODS: Localized in vivo 1H MR spectroscopy was used to measure the metabolite levels in the prefrontal lobes of control persons (n = 20) and of chronic patients before and after neuroleptic treatment (n = 34). The MR spectra of 8 cm3 voxels were compared with clinical assessment of BPRS in each subject. RESULTS: No significant metabolic lateral effect was established in both schizophrenia and control groups (P > 0.05). After neuroleptic treatment, chronic schizophrenic patients generally demonstrated a decrease of the complex of gamma-aminobutyric acid (GABA) and glutamate (Glu) containing (GABA + Glu)/creatine (Cr) ratio. CONCLUSIONS: The current follow-up 1H MR spectroscopy study shows a significant correlation between alterations of (GABA + Glu)/Cr ratio and BPRS, and supports a hypofrontality hypothesis in chronic schizophrenia. The reduction of (GABA + Glu)/Cr ratio after neuroleptic treatment may implicate the recovery of normal neuronal function in neurotransmitters. In vivo 1H MR spectroscopy may be a useful modality in follow-up evaluation of neuroleptic treatment in chronic schizophrenia.

Computer-aided design optimization with the use of a fast dose model for linear-accelerator-based stereotactic radiosurgery.

In order to efficiently plan non-spherical radiosurgical targets we have used computer-aided design optimization techniques with a fast dose model. A study of the spatial dose distribution for single or multiple non-coplanar arcs was carried out using a 18 cm diameter spherical head model. The dose distribution generated from the 3D dose computation algorithm can be represented by a simple analytic form. Two analytic dose models were developed to represent the dose for preset multiple non-coplanar arcs or a single arc: spherical and cylindrical. The spherical and cylindrical dose models compute dose quickly for each isocentre and single arc. Our approach then utilizes a computer-aided design optimization (CAD) with the use of two fast approximate dose models to determine the positions of isocentres and arcs. The implementation of CAD with fast dose models was demonstrated. While the fast dose models are only approximations of the true dose distribution, it is shown that this approximate model is sufficient to optimize isocentric position, collimator size and arc positions with CAD.