Triangular fibrocartilage and intercarpal ligaments of the wrist: MR imaging. Cadaveric study with gross pathologic and histologic correlation

To provide further understanding of the magnetic resonance (MR) signal intensities in the triangular fibrocartilage (TFC) and interosseous ligaments of the wrist, the authors performed MR imaging with gross pathologic and histologic analysis in 10 cadaveric wrists. Spin-echo T1- and T2-weighted coronal images were obtained, and 3-mm coronal sections of the specimens were then made that correlated precisely with the MR images. Normal portions of the TFC showed asymmetrical bow tie-like low signal intensity, except near the radial and ulnar attachments. Degeneration of the TFC, present in all cases, was more severe on the proximal surface and was characterized by high signal intensity on T1-weighted images and less high signal intensity on T2-weighted images. These findings differed from those in TFC perforation, which showed high signal intensity on T2-weighted images. Similar signal intensity characteristics could allow differentiation of degeneration and perforation of the scapholunate and lunotriquetral ligaments. These findings suggest that in vivo MR imaging may accurately delineate degeneration and perforation of the TFC and intercarpal ligaments.     

Balloon device for experimental graded spinal cord compression in the rat.

We have developed a balloon device that creates reproducible graded compression of the rat spinal cord. It uses a modified Camino intracranial pressure monitor bolt with a small latex balloon attached to the tip. The device is affixed to the spinous processes of two cervicothoracic vertebrae and positioned directly over an exposed segment of spinal cord. Ten compression balloons were tested and revealed reproducible pressure transmission at expansion volumes from 0.12 to 0.34 cc. Reversible graded spinal cord compression was verified by monitoring cortical somatosensory and motor evoked potentials before, during, and after cord compression. The pathophysiologic changes occurring with graded compression and the effect of therapeutic interventions can be studied in a rat model.     

Perfluoroctylbromide as a contrast agent for computed tomographic imaging of septic and aseptic arthritis

Perfluoroctylbromide (PFOB), a perfluorocarbon macrophage-labeling contrast agent, was applied to computed tomographic imaging of septic and aseptic arthritis models in rabbits. Marked enhancement of induced pyarthrosis was observed in both the knee and the sacroiliac joint. Moderate enhancement was noted in tetracycline-induced synovitis of the knee. Sterile synovitis of the sacroiliac joint and simple knee joint effusion showed no enhancement. These results suggest that PFOB is a useful contrast medium for the diagnosis of and distinction between septic and sterile arthritis.     

Effects of cyclosporin A on the splenic tissue of rats: a histomorphometric analysis

Histological studies demonstrated that long-term cyclosporin A treatment of nonantigenically challenged (untransplanted and unimmunized) Lewis rats markedly reduces the total percentage of splenic white pulp when compared to untreated control spleens (mean = 24 vs 34%, P less than 0.001). Direct measurements of periarteriolar sheaths and marginal zones demonstrated a marked reduction in size of these compartments in cyclosporin A-treated rats compared to untreated controls (P less than 0.001). In addition, there was a striking reduction in cellular density of the periarteriolar sheaths (P less than 0.001) and a minimal reduction in cellular density of the marginal zones (P less than 0.1) in the cyclosporin A-treated group when compared to untreated controls. There was no significant difference in total splenic size between the cyclosporin A-treated and the control groups, as indicated by total cross section measurements (mean = 33.3 vs 35.0, P less than 0.4). Qualitative observations of methyl green-pyroninophilic cells within and surrounding the marginal zones of the cyclosporin A-treated spleens revealed a much greater proportion of large pyroninophilic lymphocytes, which suggests that they are B immunoblasts. We conclude that long-term cyclosporin A treatment depletes splenic periarteriolar sheaths and marginal zones, compartments known to contain primary T lymphocytes, and induces an immunoblastic cell proliferation within the marginal zones and red pulp as well.     

Monitoring of motor evoked potentials with high intensity repetitive transcranial electrical stimulation during spinal surgery

Objective.Clinical utility of high voltage repetitive transcranial electrical stimulation (TES) was investigated in 46 patients undergoing spine surgery. Methods.During spinal surgery, motor evoked potentials (MEPs) were recorded from upper or lower limb muscles following high voltage repetitive TES of motor cortex under propofol and opioid/N₂O anesthesia. Results.The number of responses evoked by the double pulse stimulation was significantly higher than the single pulse stimulation. A similar finding was obtained when repetitive and single pulse stimulation was compared. Compound muscle action potentials (CMAPs) were recorded from upper and lower limbs in 4 patients with cervical spine myelopathy. The CMAP was absent on the affected side in 1 patient, which improved slightly after decompression. Radiculopathy was clinically present in 6 patients undergoing posterior lumbar decompression and fusion. No improvement of MEP was noted intraoperatively after spinal decompression and instrumentation. Conclusion.The findings suggest that intraoperative MEP monitoring is feasible method, however, its immediate prognostic value for adequacy of neuronal decompression and improvement requires further studies with larger patient population.     

Validity and reliability of the Persian version of the multiple sclerosis quality of life questionnaire

Background and Aims: To translate and test the reliability and validity of the Multiple Sclerosis Quality of Life Questionnaire (MSQoL-54) in Iranian MS patients. Setting and Design: Using a standard "forward-backward" translation, cognitive debriefing and cultural adaptation procedure, the English version of the MSQoL-54 was translated to Persian which is the Iranian official language. Materials and Methods: The subjects were multiple sclerosis (MS) patients referred to Motaharri clinic, Shiraz, South of Iran. Demographic data were recorded. Epidemiological data concerning MS type, duration of the disease, Functional System Score (FSS) and Expanded Disability Status Scale (EDSS) of patients were also provided by a qualified neurologist. Statistical Analysis: The reliability of the questionnaire was assessed by Cronbach's alpha coefficient. Construct validity was assessed through factor analysis. Factor analysis was performed to determine that the Persian version is a two-dimensional measure including physical and mental parameters. Results: Multiple sclerosis patients (female:106 (75.2%), male:35 (24.8%)), with a mean+/-SD age of 32.2+/-9.8 years were enrolled in the study. Cronbach's alpha was 0.962. There were no significant differences between each item and the mean of physical and mental scores of MSQoL-54, regarding sex, marital status and education. There was a negative significant correlation between EDSS and physical health, role limitation due to physical problems, pain, energy, health perception, social function, cognitive function, health distress, overall Quality of Life. The scaling success rates were 100%, demonstrating convergent validity of each scale. Factor analysis confirmed the construct validity of the questionnaire. Conclusions: The Persian version of the MSQoL-54 questionnaire has a good structural characteristic, it is a reliable and valid instrument and can be used for measuring the effect of MS on the Quality of Life.     

Multiple sclerosis immunopathic trait and HLA-DR(2)15 as independent risk factors in multiple sclerosis

We analysed HLA haplotypes in pairs of 78 sporadic multiple sclerosis (MS) patients and 78 healthy siblings. The presence of 2 oligoclonal IgG bands, detected by immunoblotting of the cerebrospinal fluid in healthy siblings, has previously been defined as MS immunopathic trait (MSIT), based on a cut-off derived from healthy unrelated volunteers. The frequency of MSIT was 17.9% (n=14/78 siblings). The HLA-DR(15)2 allelle was present in 21.4% (n=3/14) of the siblings with MSIT, in 40.6% (n =26/64) of the siblings without MSIT, and in 59% (n =46/78) of the patients with clinically-definite (CD) MS. The distribution of zero, one or two HLA-DR(2)15 alleles was significantly skewed towards a lower allelle count in the siblings with MSIT compared with the group of unrelated siblings with MS (P=0.002), and also lower than their related siblings with MS (P=0.1). These results suggest that the MS susceptibility gene, HLA-DR(2)15 type, does not induce MSIT, and conceivably these are two separate risk factors in the development of MS. The effect of HLA-DR(2)15 and MSIT in sporadic MS appears to be synergistic.     

Methanol poisoning: acute MR and CT findings in nine patients

Introduction Methanol poisoning is an uncommon but potent central nervous system toxin. We describe here the CT and MR findings in nine patients following an outbreak of methanol poisoning. Methods Five patients with a typical clinical presentation and elevated anion and osmolar gaps underwent conventional brain MRI with a 1.5-T Gyroscan Interna scanner. In addition nonenhanced CT was performed in another three patients with more severe toxicity. Results Bilateral hemorrhagic or nonhemorrhagic necrosis of the putamina, diffuse white matter necrosis, and subarachnoid hemorrhage were among the radiological findings. Various patterns of enhancement of basal ganglial lesions were found including no enhancement, strong enhancement and rim enhancement. Conclusion A good knowledge of the radiological findings in methanol poisoning seems to be necessary for radiologists. The present study is unique in that it enables us to include in a single report most of the radiological findings that have been reported previously.