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The clinical course and radiological and histological findings in a 30-month-old boy suffering from desmoplastic infantile ganglioglioma are reported. The child's development was normal until a series of complex partial seizures occurred at the age of 7 months. Cranial computed tomography and magnetic resonance imaging revealed a cystic mass with intensive ring-shaped contrast enhancement in the right temporal fossa without shift of intracranial structures. Histologically, the firm, grayish tumor showed an enormous amount of connective tissue, cystic areas, and some mitoses. Glial and neuronal cell lines were identified by immunocytochemical methods. Eighteen months after surgery the boy had developed well without any neurological dysfunction; no radiation or chemotherapy was given. For the first time a synopsis of radiological findings in this rare brain tumor is correlated with the results of multiple histological and immunocytochemical studies. Despite some malignant characteristics, the prognosis of this dysontogenetic brain tumor is good.

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PURPOSE: We used MR imaging to analyze retrospectively the pattern of hyperostosis occurring concomitantly with recurrent sphenoid wing meningiomas. METHODS: Bone involvement was compared in 12 corresponding CT and MR studies of 10 female patients with sphenoid wing meningiomas recurrence after earlier surgical treatment. Four of these had histologically confirmed meningiomatous infiltration of the bone. RESULTS: All patients had CT findings of localized hyperostosis of parts of the sphenoid wings. MR revealed inhomogeneous areas of slightly increased signal intensity in hyperostotic bone on T2-, proton density- and T1-weighted sequences. In nine of 10 patients, segments of the hyperostotic bone showed different degrees of gadolinium enhancement. CONCLUSIONS: Because earlier studies have revealed high incidences of meningiomatous bone infiltration in sphenoid wing meningiomas, and because infiltration was confirmed in four of our patients, we postulate that the gadolinium enhancement in the area of hyperostosis may be related to meningiomatous bone infiltration.

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The following summarize the present capability and future potential for telecommunications in radiology: 1. When used as a central archiving, reporting, and directing unit PACS principally leads to an increased economy and centralization and allows a more rational and efficient use of experienced staff and a better education for the young physicians. 2. PACS also have the capability to produce composite imaging, whereby an overall report, consisting of different radiologic examinations can be obtained. The integration of image and text data and the digital link between specialized clinical departments also makes immediate transmission of images and reports possible. 3. Analog and digital videoconferences permit long distance communication and consultation between specialists, without physicians and radiologists having to change location. These television conferences also lead to an important enhancement of education, providing interaction with specialists who might not usually be available.

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To investigate the safety, patient tolerance, and efficacy with 0.3 mmol/kg gadopentetate dimeglumine in magnetic resonance (MR) imaging of the central nervous system (CNS), a phase 3 trial was conducted in 199 patients with suspected CNS lesions. Patients received either 0.1 or 0.3 mmol/kg gadopentate dimeglumine (injection time, 15 seconds and 45 seconds, respectively). T1- and T2-weighted spin-echo sequences were performed at either 0.5 T or 1.5 T. In 80 patients with enhancing brain lesions, contrast-to-noise ratios (C/Ns) were calculated, and lesion-to-brain contrast was evaluated visually. Six patients (6%) in each dose group reported adverse events. Eight adverse events occurred with 0.1 mmol/kg and seven with 0.3 mmol/kg. Vital signs and laboratory values did not change significantly. C/N (P < .05) and visual assessment ratings were higher with 0.3 mmol/kg than with 0.1 mmol/kg. According to these preliminary results, 0.3 mmol/kg gadopentetate dimeglumine is safe and well tolerated when administered at approximately 1 mL/sec.

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A 76.2% prevalence of abnormalities was found in the cerebral MR scans of 21 patients with systemic lupus erythematosus (SLE). These patients were enrolled in the study consecutively as they presented at an immunological out-patient unit. They were not selected on the basis of neuro/psychiatric findings. Circumscribed non-periventricular brain lesions were found in 12 patients (57.1%), mainly in the frontal white or gray matter. Periventricular lesions directly adjacent to the ventricles were detected in 10 patients (47.6%). Eleven patients (52.4%) showed signs of cerebral atrophy. MRI detected more lesions in patients with clinically focal CNS lupus than in patients with seizures or patients without clinically localized findings. Eleven patients had abnormal neuropsychiatric CNS findings; there was no clear correlation between neuropsychiatric signs and symptoms and brain abnormalities as shown by MRI. Seven patients had asymptomatic lesions. Cerebral MRI proved to be the method of choice for the non-clinical diagnosis of neuropsychiatric SLE.

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OBJECTIVE: Evaluation of the perfusion and viability of the femoral head after fracture of the femoral neck is important because the outcome of conservative treatment or joint-preserving surgery is adversely affected by the development of capital osteonecrosis. We evaluated the use of MR imaging, before and after IV administration of gadopentetate dimeglumine, for assessing perfusion of the femoral head in 13 patients with acute fracture of the femoral neck. SUBJECTS AND METHODS: Multiecho (1600/30-240 [TR/TE]) MR images were obtained before contrast administration and gradient-echo (315/14, 90 degrees flip angle) MR images were obtained both before and after contrast administration. MR findings were correlated with findings on superselective digital subtraction angiograms of the vessels supplying the femoral head and with clinical-radiographic follow-up for at least 12 months. RESULTS: Digital subtraction angiography showed impaired blood supply to the femoral head in five patients. On contrast-enhanced MR images of these patients, the femoral head did not enhance and was lower in signal intensity than were the enhancing femoral shaft and neck distal to the fracture and the enhancing femoral head on the unaffected side. In the patients with persistent perfusion, contrast-enhanced MR images showed a uniform increase in signal intensity in the femoral shaft and neck as well as the femoral head; the femoral head on the fractured side showed contrast enhancement similar to that on the healthy side. CONCLUSION: These preliminary results indicate that contrast-enhanced MR imaging may be useful for noninvasive evaluation of femoral head perfusion after fracture of the femoral neck. MR findings also may aid the clinician in deciding between joint-preserving therapy and hip arthroplasty.

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Aim of this study was to assess the value of Gd-DTPA administration in MRI of cervical disk herniations. In 34 patients, showing 40 cervical disk herniations, plain proton density- and T1-weighted as well as contrast-enhanced T1-weighted 2D-FLASH images were generated. Contrast between the herniated material and the CSF already was sufficient without administration of Gd-DTPA in all cases. Sufficient contrast between the herniations and the intraforaminal structures was obtained in 13/40 cases and 40/40 cases on plain and contrast-enhanced images, respectively. Definition of the herniated disks was judged to be sufficient in 30/40 cases on plain images and 40/40 cases on contrast-enhanced images. The diagnostic value of the images was improved in 3/12 lateral and 7/8 intraforaminal herniations by contrast administration, whereas there was no significant increase in diagnostic value in posterior or posterolateral herniations. As a result, Gd-DTPA administration is recommended if definition of lateral and intraforaminal disk herniations in MRI is poor.

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MR images of 48 patients with histologically confirmed benign and malignant diseases of the pleura were retrospectively compared with CT and bioptically/surgically obtained findings. In 47/48 patients pathological changes of the pleura were visualized by increased signal intensities on T2-weighted and contrast enhanced T1-weighted MR images. This lead to a slightly improved sensitivity compared to CT, where pathological pleura findings were confirmed in 45/48 patients. MRI was able to identify 24/28 confirmed pleural effusions, whereas CT was successful in 26/28 patients. In two cases effusions not identified on CT were visible on T2-weighted MRI. 4 pleural effusions were missed with MRI.. On CT images differentiation of pleural changes vs effusions or adjacent lesions of lung parenchyma was successful in 20/28 and in 17/23 cases, respectively. Contrast enhanced T1-weighted images achieved the highest diagnostic accuracy with 22/28 and 20/23 cases, respectively. Signal intensities on MRI were unsuitable as sole criterion for the differentiation of benign and malignant diseases of the pleura. Contour and pattern of spreading of pleural changes were helpful in differential diagnosis. Nodular changes, thickening of more than 10 mm and mediastinal, circumferential and entire hemithoracic affection of the pleura were suggestive for malignant pleural disease. Infiltration of the diaphragm and the chest wall were most indicative for malignancy; here MRI (2/2 resp. 18/19 cases) was superior to CT (0/2 resp. 14/19 cases). CT was superior in the detection of pleural calcifications and osseous destruction.(ABSTRACT TRUNCATED AT 250 WORDS)

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The paper summarises imaging of orbital diseases by CT and MRI. As localisation is an important clue to differential diagnosis in orbital tumours, the different pathologies are described according to sites of prevalent occurrence. Morphological criteria of orbital pathology are described, and the more frequent entities are illustrated.

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We compared the value of gadolinium-enhanced first-pass MRI perfusion studies and HMPAO-SPECT for the assessment of regional cerebral blood flow in a prospective study of 23 intracranial tumour patients. In five tumours with homogeneous hypoperfusion and eight tumours with homogeneous hyperperfusion, tumour blood flow patterns in MRI and HMPAO-SPECT were similar. By contrast, in ten patients with inhomogeneous tumour blood flow pattern only MRI was able to differentiate between tumour areas with no or low flow, tumour tissue with high flow, and perifocal oedema with reduced flow. In HMPAO-SPECT, these inhomogeneous tumours were represented as areas of homogeneously reduced tracer retention corresponding to different tumour constituents and perifocal oedema. In conclusion, the high spatial resolution of MRI enables a detailed analysis of tumour blood flow.

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A prospective study was carried out involving 27 patients to determine whether MRT can distinguish between lymph node metastases and reactive lymph node enlargement. The results of MRT were compared with the pathological findings. Using T1 and T2 weighted sequences and proton density sequences it was not possible to differentiate between reactively enlarged lymph nodes and lymph node metastases. Following the administration of Gd-DTPA the observation of central hypo-intensity with marginal hyper-intensity is a reliable sign of a lymph node metastasis. Using the criterion of length greater than 10 mm for lymph node metastases results in a specificity of 32% and sensitivity of 75%. The use of the sonographic maximal/cross measurement quotient > 2 in the axial/coronary/sagittal dimension improves specificity and sensitivity to 94%.

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MR imaging of the orbits was performed in 59 patients with untreated Graves' ophthalmopathy (follow-up exams were performed in 11 patients). T2-relaxation times of eye muscles were calculated and correlated with duration of disease. Elevated T2 times indicating eye muscle edema were found even if ophthalmopathy had been existing for more than one year. MRI documented specific eye muscle changes and transformation of oedema to fibrosis and fatty degeneration. MRI thus allows for standardized planning of therapy and follow-up in patients with Graves' ophthalmopathy.

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The MRI and CT appearances in 48 patients with histologically confirmed benign and malignant pleural abnormalities were compared retrospectively. Abnormal pleural changes were shown in 47 out of the 48 patients by high signal intensity of the pleura in T2-weighted sequences and in contrast enhanced T1-weighted sequences on MRI. CT showed abnormalities in 45 out of 48 patients. Delineation of pleural and pulmonary changes by CT was possible in 13 out of 23 cases, and pleural disease from effusions in 15 out of 28 cases. T2-weighted MRI was successful in 14 out of 23 and 4 out of 28 cases, respectively. T1-weighted images after contrast were successful in 20 out of 23 and 22 out of 28 cases, respectively. Indications of malignant pleural disease were the presence of mediastinal or circumferential involvement or involvement of the entire pleura, thickness of more than 10 mm and nodular changes. The most reliable sign of malignancy was infiltration of the thoracic wall and the diaphragm; this was better demonstrated by MRI (18 out of 19 and 2 out of 2 cases) than by CT (14 out of 19 and 0 out of 2 cases).

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Twenty-four patients with tumors of the larynx and hypopharynx were examined with magnetic resonance imaging (MRI) and laryngoscopy. The results of MRI and laryngoscopy were then correlated with the pathology reports. Diagnostic findings of 84% of the MRI studies correlated with the pathology report, while laryngoscopy provided exact classification in 79%. MRI tended to overestimate tumor size because edema or inflammatory reactions of surrounding tissues simulated tumors. However, normal mucosa also enhanced contrast medium, restricting the value of this technique. Laryngoscopy tended to underestimate tumor size, because deep extensions of tumor and cartilage involvement were difficult to detect. Nonetheless, the utility of MRI in obtaining axial, coronal and sagittal slices was found to facilitate the preoperative staging of tumor extensions.

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The MRT and CT images of histologically confirmed intracranial ependymomas in 10 patients have been compared. All tumours were demonstrated by CT and MRT. The solid portions of the tumours showed variation in density on CT (hypodense, isodense, hyperdense, or mixed), whereas there was uniform signal intensity on MRT (T1 weighted: hypointense, T2 weighted: hyperintense). Cystic portions of the tumours (6 patients) were shown equally well by both procedures, calcifications were only shown by CT. All ependymomas were related to the ventricles. On unenhanced CT only 3 tumours were clearly delineated, whereas MRT defined all tumours satisfactorily. The significant advantage of MRT is better topographic demonstration of the tumour.

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PURPOSE: To investigate the efficacy of 0.025, 0.05 and 0.1 mmol/kg gadopentetate dimeglumine in MR imaging of patients with intracranial tumors at mid and high field strength. METHODS: In 88 patients, an open-label phase III multicenter dose-finding study was performed at 0.5, 1.0, and 1.5 T MR units. Before and after (5, 15, 25 minutes) intravenous administration of gadopentetate dimeglumine, imaging was performed with T1-weighted spin-echo sequences. RESULTS: With 0.1 mmol/kg yielding the highest values, tumor enhancement and numerical tumor/brain contrast showed dose-dependent 5-minute postcontrast values (P less than 0.05). Compared to 5-minute postcontrast values, there was no significant change at 15 and 25 minutes. Although the lowest values of enhancement were found at 0.5 T, differences in enhancement among the field strengths were not statistically significant. The numerical data were confirmed by visual assessment of tumor/brain contrast. Eighty to 90% of cases had diagnostically valuable enhancement at 0.1 mmol/kg, 50% at 0.05 mmol/kg, and 10% at 0.025 mmol/kg (P less than 0.05). There were no adverse events. CONCLUSION: Our results confirm that 0.1 mmol/kg gadopentetate dimeglumine is more effective at enhancing intracranial tumors than lower doses at mid and high field MR units.

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MR imaging was performed in 19 patients with proven multiple myeloma. Both plain and Gd-DTPA enhanced in-phase and opposed-phase gradient-echo techniques were used (0.1 mmol Magnevist/kg body weight). Plain, opposed-phase imaging demonstrated more lesions than plain in-phase imaging (35 vs. 16); enhanced opposed-phase imaging demonstrated more lesions than plain opposed-phase and enhanced in-phase imaging (47 vs. 35 and 17 lesions). These results suggest that enhanced opposed-phase images which have a high contrast between normal and infiltrated bone marrow are especially suited for MR screening in multiple myeloma.

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The aim was to validate the MRI assessment of regional cerebral blood flow. Measurements were performed on a 1.5 T imaging system using a fast T2*-weighted gradient-echo sequence. After intravenous injection of gadolinium-DTPA 30 images were acquired in the same slice position during 84 seconds. In 12 volunteers we observed a symmetrical cortical decrease of signal intensity during the passage of the contrast medium. In 9/23 patients with impairment of cerebral blood flow a circumscribed area of reduced signal intensity decrease (hypoperfusion) was found. In 4/23 patients the decrease of signal intensity was more pronounced than in normals (hyperfusion). In 9/23 patients signal intensity changes were normal. HMPAO-SPECT confirmed successful MRI assessment of cerebral blood flow in 22/23 patients.

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