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Sciatic nerve injury and dysfunction is not an uncommon cause of lower extremity symptoms in a musculoskeletal practice. We present the case of a man who presented with lower extremity weakness, pain, and cramps, and was initially diagnosed at an outside institution with bilateral S1 radiculopathies and recommended for spine surgery. He came to us for a second opinion. Electrodiagnostic testing revealed an isolated sciatic neuropathy and the patient was referred for imaging, which showed a sciatic nerve sheath tumor. Review of the literature on sciatic neuropathies shows that there can be many possible etiologies of sciatic nerve dysfunction, but that hip arthroplasty continues to be the leading risk factor. Sciatic nerve tumors are not commonly described in the literature and their definitive management remains unclear. 相似文献
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M Ardigo I Malizewsky ML Dell'Anna E Berardesca M Picardo 《Journal of the European Academy of Dermatology and Venereology》2007,21(10):1344-1350
BACKGROUND: Vitiligo is the most common pigmentary disorder with a global incidence from 0.1% to 2% in different geographical areas. Histopathology and histochemistry have shown the reduction of melanocytes in achromic patches, but microscopic changes of lesional and non-lesional skin are still not completely understood. Reflectance confocal microscopy (RCM), based on the different light reflectance index of cutaneous structures, allowed in vivo, en face microscopic evaluation of superficial skin layers with a resolution similar to skin histology. AIM: The purpose of this study was to evaluate RCM features of lesional and non-lesional skin of vitiligo patients. Moreover, re-pigmented areas were taken into consideration in order to evaluate melanocyte response to ultraviolet B (UVB) radiation. SUBJECTS AND METHODS: Sixteen patients of different phototypes affected by active non-segmental vitiligo and 10 controls were enrolled in the study. In vivo skin imaging was done using a commercially available RCM (Lucid, Vivascope 1500. Re-pigmented areas from 6 to 16 patients (after UVB narrow-band therapy) were also examined. RESULTS: Vitiligo lesions showed the disappearance of the bright rings normally seen at the dermo-epidermal junction. Moreover, non-lesional skin of vitiligo patients showed unexpected changes as the presence of half-rings or scalloped border-like features of the bright papillary rings. In re-pigmented areas after UVB narrow band therapy, the presence of activated, dendritic melanocytes was seen. CONCLUSIONS: Considering our results, and following further studies, RCM clinical applications could be used in the therapeutic monitoring and evaluation of the evolution of vitiligo. 相似文献
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Sleep spindles in normal elderly: comparison with young adult patterns and relation to nocturnal awakening, cognitive function and brain atrophy 总被引:1,自引:0,他引:1
M Guazzelli I Feinberg M Aminoff G Fein T C Floyd C Maggini 《Electroencephalography and clinical neurophysiology》1986,63(6):526-539
Visual measurements of sleep spindles were carried out in 48 elderly and 20 young normal adults. Computed tomography brain scans and psychometric testing were also performed. Earlier findings of reduced spindle abundance, amplitude and duration in the elderly were confirmed. In addition, we demonstrated a linear increase in spindle density and duration across NREMPs in young adults that was absent in the elderly, indicating that age affects the temporal pattern as well as the quantity of spindles. Contrary to what seemed a highly plausible hypothesis, the amount of waking in the elderly was not inversely correlated with spindle abundance, confirming earlier observations (Feinberg et al. 1967) but in a much larger group. This finding suggests that spindle abundance does not reflect the integrity of the systems that maintain the brain in NREM sleep. We also were unable to show any clear evidence that relative preservation of spindles in the elderly is associated with relative preservation of cognitive skills: psychometric performance and spindle measures were, in most instances, not significantly correlated. However, the test of this hypothesis was limited by the high level of function and the narrow range of impairment of these Ss. One intriguing positive finding was the significant inverse relation between ratings of sulcal atrophy and spindle amplitude. This observation suggests an etiology for the reduced amplitude of the sleep EEG in old age. This change is one of the most striking effects of age on brain electrophysiology. 相似文献
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Kinnison ML; Perler BA; Kaufman SL; Mitchell SE; Kadir S; Williams GM; White RI Jr 《Radiology》1986,160(3):727-730
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications. 相似文献