Occurrence of MRI abnormalities in patients with isolated optic neuritis.

24 patients with clinically isolated optic neuritis (ON) were examined with MRI. Only 5 patients (22.9%) had a normal MRI scan. The number of detected clinically silent lesions ranged from 0 to 38. They were mainly located in the frontal and parietal white matter. All patients with more than 3 lesions on MRI had pathological findings in CSF. There was no correlation between the number and location of lesions and age at onset of ON.

Magnetic resonance imaging in the evaluation of treatment in multiple sclerosis.

Magnetic resonance scans of 74 patients with multiple sclerosis participating in a controlled trial were compared 6 months before and at the end of a 24-32 months-treatment period with either Cyclosporin A (n = 31) or Azathioprine (n = 43). Both qualitative rating and computation of lesion volume showed deterioration in more than 40% of the patients, while by clinical criteria only 10-30% were worse. No significant difference was noted when the two treatment groups were compared. If careful repositioning and standardized image parameters are used, MRI is an indispensable tool for the objective determination of disease progression in MS although it cannot replace clinical examination.

An attempt to quantify magnetic resonance imaging in multiple sclerosis--correlation with clinical parameters.

The diagnostic value of magnetic resonance imaging (MRI) in multiple sclerosis (MS) is uncontested. But only little information exists on its usefullness in monitoring disease activity. We describe a method of quantification that can be performed in longitudinal MRI-investigations. We used a standardized method of scanning and determined the area of demyelinating lesions with an interactive planimetric computer system. In order to determine the approximate lesion volumes, the computed area was multiplied by the slice thickness. In 89 patients with clinically definite MS we found an average lesion volume of 11900 mm3. The mean score in Kurtzke's expanded disability scale was 3.0. The correlation between computed lesion volume and neurological deficit was significant, but only weak (rho = 0.3). We conclude, that planimetric evaluation of MRI can be a valuable supplement to clinical rating scales in MS patients. The method described here, used in combination with high spacial resolution and better tissue specificity of latest generation MRI scanners, could be helpful in the evaluation of treatment in many other CNS diseases.

Phagocytic and chemotactic function of polymorphonuclear and mononuclear leucocytes in patients with recurrent staphylococcal infections.

From 21 patients with chronic or recurrent staphylococcal infections, phagocytosis and intracellular killing of Staphylococcus aureus by polymorphonuclear (PMN) and mononuclear (MN) leucocytes were evaluated. Also chemotactic responsiveness and the capacity of their sera to opsonize Staph. aureus was tested. The chemotactic, phagocytic and bactericidal capacity of PMN's and MN's from patients was significantly decreased. The mean uptake of Staph. aureus by patient PMN's and MN's was 65% and 44%, respectively, as compared to 85% and 75% observed with PMN's and MN's from 38 healthy donors. The phagocytic activity of 17/21 patients (81%) was below the normal range. A decreased chemotactic mobility and bactericidal capacity of patient leukocytes was also found and was always accompanied by a decreased rate of ingestion. Although a great variability was noted in the phagocytic capacity of leucocytes from patients tested repeatedly over periods up to 82 weeks, the mean value for phagocytosis remained below the normal range in 10/11 patients included in the follow-up study. Except for 1 patient with dysgammaglobulinemia, sera from the patients contained normal amounts of immunoglobulins and complement (CH50 and C3), and they all effectively opsonized Staph. aureus. The results indicate that defects in leucocyte function may be frequently involved in the pathogenesis of recurrent Staph. aureus infections.