[Intracranial tumor-like lesions in children and young adults with multiple sclerosis]. / Intrakranielle tumorähnliche Läsionen bei Kindern und jungen Erwachsenen mit multipler Sklerose.

Atypical early manifestations of multiple sclerosis (MS) are common in children and young adults. 6 patients (aged 5 to 33 years) were examined by MR because of confusing neurological manifestations. In addition to small MS lesions there were also large intracerebral lesions which, however, did not occupy additional space but which looked more like tumours or abscesses. The lesions were sharply demarcated cystic formations with margins that enhanced with contrast. The diagnosis of these lesions presents difficulties, the differential diagnosis including MS and its variants, neoplastic, infectious and vascular processes. MR can provide valuable diagnostic information.

[Interpretation of MR tomography findings in trauma surgery]. / Zur Interpretation kernspintomographischer Befunde in der Unfallchirurgie.

MR-Imaging is well established as the most sensitive method for the diagnosis of avascular necrosis of the femoral head. In this paper preliminary results are analyzed in an attempt to clarify whether as in a vascular necrosis of the femoral head. MR changes after trauma or surgery allow conclusions concerning the vitality of the bone. Comparison of clinical, MR and histological findings revealed that we cannot yet differentiate between fibrosis of the bone marrow with sustained vitality of the osteocytes and bone necrosis. Therefore, conclusions with implications for therapy should be drawn with extreme care.

Graves ophthalmopathy: role of MR imaging in radiation therapy.

Twenty-three patients with Graves ophthalmopathy who underwent radiation therapy were monitored by means of magnetic resonance (MR) imaging. T2 relaxation times of extraocular muscles and orbital fat, areas of extraocular muscles, and degree of exophthalmos were measured by means of MR imaging at the beginning, at the end, and 3 months after completion of radiation therapy. As a result, patients with primarily elevated T2 times of extraocular muscles showed a better therapy response regarding muscle thickening than patients with primarily normal T2 times. Elevated T2 times, which probably represent acute inflammatory changes, were markedly decreased at the end of therapy. Therefore, quantitative MR imaging favors the choice of anti-inflammatory therapy regimens in patients with elevated T2 times of extraocular muscles. However, the clinical response (activity scores) to the low-dose treatment protocol that was used did not correlate well with primarily elevated T2 times. Furthermore, T2 times increased again after cessation of therapy. Whether a higher radiation dose or a different fractionation scheme leads to better results must be clarified by means of further study.

[Diagnosis of Perthes disease using magnetic resonance tomography]. / Zur Diagnostik des Morbus Perthes durch Magnetresonanztomographie.

Lateral displacement of the femoral head and slight flattening are typical radiological signs of early Legg-Calvé-Perthes disease. There is the value of magnetic resonance imaging (MRI) in demonstrating the congruity of the acetabular and femoral articular surfaces, the cartilage, the femoral head containment, intracapsular joint effusion, and hypertrophy synovium without using any ionizing radiation. Loss of containment because of lateralisation seems to be the result of medial hypertrophy of the femoral head cartilage. The hips show a characteristic low-intensity signal in T1-weighted images representative of necrotic areas of the capital epiphysis. The extent of involvement and revascularisation can be identified in Legg-Calvé-Perthes disease.

Intrasellar cysticercosis mimicking a pituitary adenoma.

A case of a 50-year-old female with an intrasellar and suprasellar cysticercus cyst, which was pre-operatively misinterpreted as a macroadenoma of the adenohypophysis is described. Cranial computed tomography revealed a homogeneous hyperdense intrasellar and suprasellar lesion. In T1-weighted magnetic resonance images, a spotty hyperintense tumor of the sellar region was shown.

MRI-assisted radiation therapy planning of brain tumors--clinical experiences in 17 patients.

A new and simple method for precise determination of lateral opposed treatment portals was developed and used in 17 patients. Compared to CT, MRI led to significant changes of portals in 59% (10/17) of cases. Individual shielding blocks could be precisely designed by use of our new method. MRI is the procedure of choice in local radiation therapy planning of brain tumors.

MRI of trigeminal neuralgia: initial clinical results in patients with vascular compression of the trigeminal nerve.

The most common cause of the idiopathic trigeminal neuralgia are tortuous arteries in the prepontine space. The trigeminal nerve can be compressed by the superior cerebellar artery, the inferior cerebellar artery, or the basilar artery. Seldom the nerve is traumatised by an enlarged vein. Because an operative decompression of the nerve can relieve pain, a preoperative evaluation is needed. Angiography of the vertebral arteries is able to predict a tortuous artery close to the trigeminal nerve but cannot show the nerve itself. MRI can show tortuous vessels and the trigeminal nerve together on one single image by means of a 3D gradient-echo FLASH sequence with an effective slice thickness of approximately 1 mm and secondary reconstructions in every desired plane. MRI thus provides an efficient tool for the evaluation of patients with trigeminal neuralgia.

MRI of transient osteoporosis of the hip.

Among the available imaging techniques such as conventional radiography, radionuclide bone scan, and computed tomography (CT), magnetic resonance imaging (MRI) has made significant contributions to the diagnosis of acute hip joint disease in adults by enabling early differentiation between such conditions as idiopathic avascular femoral head necrosis, septic coxitis, degenerative disease, and tumors. In this study we investigated the use of MRI for evaluation of patients with transient osteoporosis (TO). MRI with T1- and T2-weighted sequences in coronal, transverse, and sagittal sections was performed in 12 patients with retrospectively confirmed TO, both at the onset of the disease and later as follow-up procedure. MRI revealed three typical stages of TO: a diffuse stage, a focal stage, and a residual stage. Characteristic symptoms of TO are hip pain and a need for protective splinting of the hip joint. Conventional radiographs show demineralization of the hip joint without joint space narrowing. Clinical, radiologic, and MRI findings normalize within 6-10 months, indicating that TO has a good prognosis with complete restoration of bone density.

[Intraspinal anomalies in myelomeningocele]. / Intraspinale Anomalien bei der Myelomeningozele.

This study reports the results of MRI analysis of the spinal cord in 83 patients with myelomeningocele. 63 patients had a "tethered cord" or a "suspected tethered cord". In 14 cases we found a "hydro-/syringomyelia". In only 2 cases there were no pathological findings. The influence especially of the "tethered cord" and the "hydro-/syringomyelia" on the development of deformities of the locomotor apparatus is discussed. Concerning this problem the experience reported in the literature is not sufficient enough to make final statements. However, in cases of deterioration of the neurological status in patients with myelomeningocele the influence of intraspinal anomalies should be considered giving rise to further diagnostic examinations.

[Diagnosis of transitory osteoporosis of the hip and its imaging in magnetic resonance tomography]. / Zur Diagnostik der transitorischen Osteoporose der Hüfte und deren Darstellbarkeit in der MR-Tomographie.

Magnetic resonance (MR) imaging may distinguish transient osteoporosis of the hip from more severe hip diseases. 12 patients with transient osteoporosis of the hip underwent MR imaging. The initial and follow-up studies included T1- and T2-weighted images in coronal, transverse or sagittal planes. There were revealed 3 stages: diffuse-, focal-, and residual stage. This syndrome is characterized by hip pain, limping, and osteoporosis of the femoral head with preservation of the joint space. The clinical symptoms and abnormalities on MR images disappeared completely within 6-10 months.

Magnetic resonance imaging of the craniocervical junction in rheumatoid arthritis: value, limitations, indications.

The cervical spine is the second most common location for manifestation of rheumatoid arthritis (RA). Symptoms are typically related to involvement of the craniocervical junction. Unfortunately, conventional radiographic examination is often unable to demonstrate that RA is the cause of such symptoms. Magnetic resonance imaging (MRI) provides an unique opportunity to visualize nerves, connective tissue, and bone in all planes without the use of contrast agents. These features suggest that MRI could provide important information related to RA of the cervical spine. The possibilities and limitations of MRI were therefore evaluated in 60 patients with cervical RA. The main objective of this study was to correlate symptoms and clinical findings with MRI results to establish indications for this imaging procedure.

[Magnetic resonance tomography using gadolinium-DTPA in the diskectomy syndrome--a reliable method of identifying a recurrent prolapse in scar tissue]. / Die Kernspintomographie mit Gadolinium-DTPA beim Diskektomie-Syndrom--eine zuverlässige Methode zur Identifizierung eines Rezidivprolapses im Narbengewebe.

The non invasive diagnostic possibilities of MR have resulted in better diagnosis of degenerative spinal diseases. Twenty-one patients with failed back surgery syndrome (postdiscectomy syndrome) were studied to evaluate the possibility of 1-Tesla magnetic resonance (MR) imaging with gadolinium diethylene triamine pentaacetic acid (Gd-DTPA) in differentiating post operative scar tissue from recurrent disc herniation. The enhanced MR studies correctly depicted the character of abnormal epidural tissue in all patients. We conclude that MR with GD-DTPA might be the method of choice to differentiate reliably postoperative epidural fibrosis from recurrent disc prolapse.

[Femur head necrosis. Diagnosis and morphologic analysis using roentgen, scintigraphy, computerized tomography and magnetic resonance tomography]. / Die Femurkopfnekrose. Diagnostik und morphologische Analyse mittels Röntgen, Szintigraphie, Computertomographie und Magnetresonanztomographie.

35 patients with a total number of 53 AVN were examined with conventional radiographs (n = 53), radionuclide scans (n = 37), CT (n = 19) and MRI (n = 53). Findings were classified according to FICAT (stage 0-IV). With a sensitivity of 96.2% and a specificity of 98.1% MRI proved to be the most accurate imaging modality especially in early stages. CT proved to be a reliable technique, too, although accuracy was less compared with MRI. Radionuclide scanning was of minor value with a sensitivity of 62.1% and a specificity of 59.5%. Typical findings with plain radiographs, radionuclide scans, CT and MRI in different stages of AVN are described.

[Intracranial hemorrhage in MRT]. / Die kranielle Blutung in der MRT.

About 10% of all intracranial findings in cranial MRI were hemorrhages, or findings associated with bleeding. There was great variation in the hemorrhages as a result of their location and their age, and this could disguise the underlying lesions. Therefore a knowledge of the typical appearance of spontaneous bleeding and tumor bleeding is necessary for interpretation of the MRI findings. During its course, cerebral bleeding shows all of the known interactions between biochemical and histological factors and MRI signal. Thus, an understanding of the variations during the clinical course of bleeding is helpful for a better understanding of contrast mechanisms in MRI.

[Transient osteoporosis or femur head necrosis? Early diagnosis using MRT]. / Transitorische Osteoporose oder Femurkopfnekrose? Frühdiagnose mit der MRT.

Transient osteoporosis of the hip is a syndrome that does not seem to be widely known; this is also true for its radiological appearance. It is often mistaken for avascular necrosis of the femoral head, metastatic or inflammatory disease. These differential diagnoses lead to more or less invasive procedures, although transient osteoporosis does not require more than immobilisation for complete remission. MRI was done in 38 patients with acute hip pain, 13 had femoral head necrosis and 8 transient osteoporosis. Follow-up studies via MRI in patients with transient osteoporosis revealed 3 stages (diffuse, focal, residual) during the clinical course of which stage II is similar to femoral head necrosis but always without the typical sclerotic rim.

Bone grafting in total hip replacement. Preliminary results with MRI.

MRI of ten hip joints in nine patients with total hip replacement and reconstruction of the acetabulum with autologous bone grafts, were reviewed. The viability of inserted bone grafts was clearly documented by MRI. Characteristic differences in signal intensity between autologous and homologous bone grafts are discussed. Despite extended metallic artifacts in the operated region, sufficient diagnostic information was available in most cases. No side effects were reported.

[Acute hip pain in the adult--assessment by magnetic resonance tomography]. / Der akute Hüftschmerz des Erwachsenen--Abklärung durch MR-Tomographie.

Using the modern cross-sectional imaging technique of MRI, significant improvement has been achieved in the early diagnosis of acute hip diseases, such as avascular femoral head necrosis, transient osteoporosis, coxitis, and tumors, the demarcation of which can be seen by MRI. Studies with MRI in patients with transient osteoporosis have revealed three stages during the clinical course. The focal stage is similar to femoral head necrosis, but always without the typical sclerotic rim. To obtain complete remission, transient osteoporosis only requires immobilization. There are difficulties in diagnosing infected and neoplastic processes.