Discrete synchronous multifocal osteoid osteoma of the humerus.

A 24-year-old patient is described who had a 4-year history of pain in the right upper arm, with distinct night pain, that responded to salicylates. From the findings on conventional radiography, bone scintigraphy and MRI a multifocal osteoid osteoma was suspected, with one focus in the cancellous region of the greater tuberosity and a second cortical focus at the proximal humeral diaphysis. The resection "en bloc" of both tumors and histological examination confirmed the diagnosis. The patient was painfree after the curative resection of the two osteoid osteomas. Osteoid osteoma is a frequently found benign bone tumor, accounting for approximately 11% of cases. In rare cases a multicentric occurrence has been described. A possible occurrence of more than one osteoid osteoma in a single bone, not verified histologically, has been reported only three times in the literature. In patients with scintigraphic and radiographic findings of two foci, discrete synchronous multifocal osteoid osteomas should be suspected.

One-year MR imaging follow-up of patients with multiple sclerosis under cortisone therapy.

Twenty patients with relapsing/remitting course of MS were studied four times with MR imaging over the course of one year. First MR was undertaken during the acute relapse, afterwards patients were given cortisone therapy for four to six weeks. The second MR study followed 4-6 weeks after the first, the patients at this time being in remission. The third MR study was carried out 4 months after the first, the last scan one year after the first. The total number of lesions varied, though not greatly, over the whole follow-up, but there was an influence of the clinical course of MS on the pattern of lesions in MR imaging, mostly in respect to the number of confluences and the size of the lesions. Follow-up over one year showed that the inflammatory process produced an increase in the number of plaques, independent of the fact that most patients stayed in remission. A delayed effect of the cortisone therapy on the size, number, and confluence of plaques is suggested whilst clinical signs improved in most cases immediately after the beginning of drug therapy. Independent of the clinical course of the disease in some cases plaques previously seen vanished and others appeared in one and the same examination.

MR imaging in multiple sclerosis: comparison with clinical, CSF, and visual evoked potential findings.

MR examinations of 136 patients with multiple sclerosis (MS) were evaluated to correlate the results with clinical, CSF, and visual evoked potential (VEP) findings. In addition, 22 of the 136 patients were studied several times during a 5-month follow-up period. It was demonstrated that MR is superior to CSF and VEP findings in establishing cerebral alterations in MS. A relationship between the results of CSF and VEP examinations and the MR results could not be detected. Negative CSF and VEP results corresponded to positive MR imaging and vice versa. In our series, five negative MR results were obtained in patients with clinically proved MS. The extent of alterations shown up by MR corresponds to the duration of the disease; in particular, more confluent abnormalities in the periventricular region were found in patients with long-standing disease. More plaques were found in patients with a primary relapsing/remitting course of the disease than with the primary chronic progressive form. The clinical course and the grade of disability did not correspond to differences in MR imaging. Follow-up demonstrated that most lesions remain unchanged (72-79%); increases and decreases in the size of the plaques seem to depend on the clinical course. These results suggest that MR is the most sensitive technique for establishing the diagnosis of MS.

Relationship of nuclear magnetic resonance examinations to clinical data, cerebrospinal fluid findings and visual evoked potentials in multiple sclerosis.

We examined 150 patients with a 0.5 Tesla MR system. Fourteen patients were excluded from the study, because, in addition to the clinical signs of multiple sclerosis, they showed other abnormalities (spinal canal narrowing, embolic disease, Vitamin B12 deficiency, etc.). The results of the 136 examinations were related to the duration of disease, index of impairment on Kurtkze's disability scale, the clinical course, and the CSF and VEP results. The MR studies were evaluated in a semiquantitative manner. Patients with a long duration of disease demonstrated more changes than did cases with a short course. We found more periventricular confluences and more white matter plaques in the centrum semiovale. In addition, more lesions were seen in patients with a severe course of disease. All patients with negative CSF results (n = 13) showed positive MR examinations, and vice versa, patients with positive CSF findings showed negative MR results (n = 5). First results of a follow-up study demonstrate that most abnormalities in MR are not related to the clinical course or therapeutical procedure.