Computerized tomography and auditory-evoked potentials. Use in the diagnosis of olivopontocerebellar degeneration

The pneumoencephalogram has been the only diagnostic test available to confirm the diagnosis of olivopontocerebellar degeneration during life. This study suggests that pneumoencephalography may be obsolete and that the diagnosis of olivopontocerebellar degeneration may be established by abnormalities seen during computerized tomography (CT) and by abnormal responses to auditory-evoked potentials (AEPs). The combination of CT scans and AEPs provides a completely nontraumatic method of diagnosis in olivopontocerebellar degeneration and eliminates the need for pneumoencephalography.     

Supraacetabular insufficiency fractures

Insufficiency fractures in the supraacetabular region were identified in five women, aged 55-83 years. Factors contributing to the diminished resistance of their bones included postmenopausal osteoporosis, steroid therapy, radiation therapy, and rheumatoid arthritis. The supraacetabular fractures were seen on routine radiographs as hazy bands of sclerosis located immediately above and parallel to the acetabular roof. All five patients had additional fractures in the spine or pelvis. Supraacetabular insufficiency fractures may be an unsuspected cause of hip pain, especially in older women.     

Vasodilator agents and supracollicular transection fail to inhibit cortical spreading depression in the cat

It remains an open question as to whether cortical spreading depression (CSD) is the pathophysiological correlate of the neurological symptoms in migraine with aura. In the experimental animal, CSD is an electrophysiological phenomenon mainly mediated via NMDA receptors. However, according to case reports in humans, visual aura in migraine can be alleviated by vasodilator substances, such as amyl nitrite and isoprenaline. There is also circumstantial evidence that brainstem nuclei (dorsal raphe nucleus and locus coeruleus) may play a pivotal role in the initiation of aura. In this study, CSD was elicited in alpha-chloralose anesthetized cats by cortical needle stab injury and monitored by means of laser Doppler flowmetry. Topical application of isoprenaline (0.1-1%) and amyl nitrite (0.05%) onto the exposed cortex had no effect on the elicitation or propagation of CSD. Also, after supracollicular transection, subsequent CSDs showed no differences in the speed of propagation and associated flow changes. We conclude from these data that--given CSD probably exists in humans during migraine--spreading neurological deficits during migraine aura are independent of brainstem influence and have a primarily neuronal rather than vascular mechanism of generation.     

Hereditary coproporphyria: an imitator of multiple sclerosis.

Hereditary coproporphyria can cause both peripheral neuropathy and central nervous system abnormalities. There are several similarities between multiple sclerosis and hereditary coproporphyria that are probably due to the central nervous system dysfunction present in both. This report describes a 62-year-old man with a five-year history of progressive paraparesis initially diagnosed as multiple sclerosis. Supporting evidence for the diagnosis of a demyelinating disease included three oligoclonal bands in the patient's cerebral spinal fluid, a prolonged visual evoked response bilaterally, abnormal sensory evoked potentials, and an area of increased signal in the posterior cervical cord suggestive of demyelination that was demonstrated on magnetic resonance imaging (MRI). Features atypical for multiple sclerosis were hypoactive deep-tendon reflexes, electromyographic evidence of peripheral neuropathy, and severe constipation. Elevated urine porphyrins and decreased levels of coproporphyrinogen oxidase confirmed the correct diagnosis of hereditary coproporphyria. The patient improved after being placed on a high-carbohydrate diet. Although central demyelination is known to occur in patients with porphyria, delayed evoked potentials and MRI abnormalities have not been previously reported.     

Ankle: surface coil MR imaging at 1.5 T

High-field surface coil magnetic resonance (MR) images were obtained of 12 ankles: two from healthy volunteers, seven from patients, and three from fresh cadavers. The cadaver ankles were sectioned in the coronal, sagittal, and axial planes for direct comparison with the MR images. Plain film confirmation of pathologic conditions was obtained in all patients, and five underwent arthroscopy or surgery, or both. MR imaging provided excellent delineation of ligaments and cartilaginous structures in all cases.     

The prevalence of Mycoplasma fermentans in patients with inflammatory arthritides.

OBJECTIVES: To search for evidence that Mycoplasma fermentans is involved in the pathogenesis of some forms of human arthritis by testing for the presence of mycoplasmal DNA in joint material. METHODS: M. fermentans DNA was detected by the identification of a 104-base pair amplification product of the polymerase chain reaction (PCR). RESULTS: M. fermentans DNA was detected in synovial fluid samples from six (17%) of 35 patients with rheumatoid arthritis (RA) and 18 (21%) of 85 patients with seronegative arthritis. These detection rates were significantly greater than in samples from patients with osteoarthritis or crystal synovitis, none of 26 of these being positive. CONCLUSIONS: M. fermentans could be involved in the pathogenesis of some forms of inflammatory arthritis and this possibility is worthy of further study.     

Platelet transfusion from donors mismatched for crossreactive HLA antigens

Increments in platelet counts following the transfusion of platelets mismatched for crossreactive antigens were evaluated in 67 patients with broad alloimmunization to HLA antigens. The corrected increments following 100 HLA, A-matched and B1U- or B2U-matched transfusions were compared with the increments following 307 B1X- or B2X-matched transfusions. HLA-A3 platelets were tolerated poorly by A1 and A11 recipients, as were A1 and A11 by A3 recipients, B17 and BW21 by recipients in the B7 crossreactive group, B5 by B15 and B17 recipients, and B27 by recipients in the B5 crossreactive group. B12 and BW21, and B8 and B14 platelets were not tolerated bidirectionally. Antigens associated with good increments included A28 in A2 recipients, B18 and BW16 (C match) in recipients in the B5 crossreactive group, B5 in B18 recipients, BW22 and B7 in recipients in the B7 crossreactive group. A1 and A11 were transfused successfully bidirectionally. These observations suggest that some private antigens within crossreactive groups are more immunogenic than others and support the observation of others than B17 and BW21 are not in the B5 crossreactive group.