Low-dose, short-term oral prednisone in the treatment of carpal tunnel syndrome.

We evaluated the effectiveness of low-dose, short-term oral prednisone in ameliorating the pain and other symptoms of carpal tunnel syndrome (CTS) in a randomized, double-blind, placebo-controlled study of patients with mild to moderate CTS. Prednisone, in doses of 20 mg daily for the first week and 10 mg daily for the second week, resulted in significant improvement in global symptom scores. The effect was rapid, but gradually waned over 8 weeks of observation. This approach may provide a treatment alternative in the short-term, conservative management of CTS.

Neuro-Behçet's disease: CT and clinical correlates.

We examined the serial CTs and clinical courses of five patients with neuro-Behçet's disease and reviewed ten previously reported cases, all with focal CT abnormalities. The CT lesions were in the brainstem (8 patients), basal ganglia (7), thalamus (4), or hemispheric white matter (7). Of the 13 patients who received contrast, nine had lesions that showed enhancement. In five, lesions were visualized with contrast that were not apparent without it. The CT lesions were usually accompanied by corresponding clinical deficits, although in some patients deficits were more extensive than the CT predicted. In nine patients, contrast enhancement decreased or disappeared over days to weeks, often with associated clinical improvement. In eight patients followed serially, CT abnormalities resolved completely or substantially. Based on these cases, we conclude that (1) CT abnormalities of gray and white matter occur commonly in neuro-Behçet's disease with focal deficits, and help support the diagnosis; (2) CT abnormalities, particularly contrast enhancement, correlate well with the activity of parenchymal disease; and (3) the concomitant improvement of clinical and CT abnormalities with resolution of contrast enhancement suggests that partially reversible inflammatory changes associated with breakdown of the blood-brain barrier may produce some of the neurologic and radiographic deficits in this illness.

Prevalence of peripheral neuropathy in injection drug users.

BACKGROUND: Nucleoside analogue reverse transcriptase inhibitors are a critical component of antiretroviral therapy in HIV-infected persons. Several of these medications cause painful, dose-limiting peripheral neuropathy (PN), which may develop earlier and more intensely in persons with preexisting neuropathy. The prevalence of baseline peripheral neuropathy in injection drug users (IDUs), one of the largest populations of HIV-infected persons, has not been described, yet has important implications for the selection of antiretroviral therapy. METHODS: The authors performed a cross-sectional study of PN in 212 HIV-seronegative and HIV-seropositive IDUs using detailed neurologic histories, physical examinations, quantitative electrophysiologic study, and quantitative sensory testing. Data were used to assign patients to one of four positive categories of PN or one of two negative categories. RESULTS: PN was present in 24.5% of HIV-seronegative IDUs, three to four times the reported frequency for HIV-seronegative persons in the general or male homosexual population. PN was present in 32.1% of HIV-seropositive patients. PN was axonal in nature and associated with increased age and alcohol use. PN was asymptomatic in 81% of HIV-seronegative and 71% of HIV-seropositive patients with PN. CONCLUSIONS: There is a high prevalence of PN in HIV-seronegative IDUs. Although these PNs do not seem to predispose HIV-seropositive IDUs to HIV-related PN, they may increase the likelihood of iatrogenic neuropathy. Intravenous drug users may need more diligent monitoring when administered nucleoside analogues than patients in risk groups with lower endemic rates of PN.

Central pain from cerebral abscess: thalamic syndrome in AIDS patients with toxoplasmosis.

We describe two patients with acquired immunodeficiency syndrome (AIDS) who developed classic thalamic syndrome (TS) due to Toxoplasma abscesses in the thalamic region. Treatment with amitriptyline provided substantial relief in both patients. Postmortem examination in one case revealed a lesion in the internal capsule and thalamic reticular nucleus. These observations indicate that (1) TS can result from an isolated lesion in the internal capsule and reticular nucleus of the thalamus, (2) cerebral abscess can cause classic TS, (3) central pain can be added to the many pain syndromes that afflict AIDS patients, and (4) an analgesic response to amitriptyline is possible in these patients.

Miller Fisher syndrome: axonal, demyelinating or both?

Controversy exists concerning whether Miller Fisher syndrome (MFS) is the result of a predominantly axonal or demyelinating polyneuropathy and whether the Guillain-Barré syndrome variant of acute ataxia and areflexia without ophthalmoplegia, ataxic Guillain-Barré syndrome (atxGBS), has a distinct pathophysiology. We explored these issues by reviewing the electrophysiologic features of 6 patients with MFS and 2 patients with atxGBS. EMG laboratory records were reviewed and electrophysiologic findings were categorized as axonal or demyelinating neuropathy using previously defined criteria. Of the 6 patients with MFS, 5 had electrophysiologic evidence suggestive of an axonal, predominantly sensory polyneuropathy; only 1 patient met criteria for demyelinating polyneuropathy. Both patients with atxGBS had demyelinating sensorimotor polyneuropathy. Electrophysiologic abnormalities in MFS typically suggest a predominantly axonal, sensory polyneuropathy, though demyelinating forms occur and may be under-diagnosed using current criteria. AtxGBS, in our experience, is a predominantly demyelinating polyneuropathy.

Electrophysiologic correlates of weakness in L5/S1 radiculopathy.

INTRODUCTION: Management of patients with radiculopathy involves estimating the degree of physiologic and anatomic injury, and weighing that to predict the likely clinical course. OBJECTIVE: To determine whether low distal peroneal and tibial CMAP amplitudes correlate with weakness and fibrillations of functionally relevant muscles in L5/S1 radiculopathy (LSR). METHODS: We reviewed clinical and electrophysiologic data in 66 consecutive patients with LSR. RESULTS: A significantly greater number of patients with low peroneal CMAP amplitudes had weakness of L5 (p = 0.025) and S1 innervated leg muscles (p < 0.001). Low tibial CMAP amplitudes were also associated with weakness of S1 innervated muscles (p < 0.038). The association of low peroneal CMAP amplitudes with weakness persisted when weakness of at least 3 muscles was considered in the analysis for L5 (p < 0.0001) and S1 (p = 0.014) innervated muscles. CONCLUSIONS: Low peroneal and tibial CMAP amplitudes may serve as surrogate measures for segmental weakness of functionally relevant muscles in LSR.

Late motor involvement in cases presenting as "chronic sensory demyelinating polyneuropathy".

Chronic inflammatory demyelinating polyneuropathy (CIDP) is usually characterized by prominent motor deficits. A pure sensory presentation, labeled chronic sensory demyelinating neuropathy (CSDN), has been reported, but it is unclear if this neuropathy is a distinct clinical and immunologic entity or merely the sensory presentation of the more usual sensorimotor CIDP. We describe 5 patients with what initially appeared to be CSDN; 3 subsequently developed substantial weakness coincident with the electrophysiologic appearance of multifocal motor conduction block. These cases indicate that, in some cases, CSDN may be a transitional clinical stage of CIDP in which the more usual sensorimotor deficits develop later. Immune-based therapy, including intravenous immunoglobulin, was found to be effective in both the pure sensory and sensorimotor types.

Treatment of mononeuropathy multiplex in hepatitis C virus and cryoglobulinemia.

Recent reports advocate alpha-interferon (alpha-Ifn) treatment for mononeuropathy multiplex in hepatitis C virus-associated cryoglobulinemia. We report 2 patients with this disorder to describe two underrecognized treatment outcomes--worsening of polyneuropathy with initiation of alpha-Ifn, in the absence of immunosuppression, and deterioration of liver function with prednisone, despite improvement of polyneuropathy.

Autonomic dysfunction in idiopathic carpal tunnel syndrome.

While the sensorimotor features of carpal tunnel syndrome (CTS) are well known, a prospective, systematic study of autonomic disturbances in CTS is lacking. Of 139 limbs with CTS (76 patients), autonomic symptoms were reported in 76 (47 patients). Of these, 59% consisted of swelling of the fingers, 39% dry palms, 33% Raynaud's phenomenon, and 32% blanching of the hand. Sympathetic skin response (SSR) had a sensitivity/specificity ratio of 34/89% in CTS with autonomic symptoms. The presence of autonomic disturbances was significantly associated with female gender (odds ratio 4.06, 95% CI 1.5-11.4, P = 0.007), SSR abnormalities (odds ratio 4.3, 95% CI 1. 6-11.4, P = 0.003), and severity of electromyographic findings (odds ratio 1.8, 95% CI 1-3.3, P = 0.04) but not age, duration of disease, or clinical severity in a binary logistic regression model. Autonomic disturbances are common (55%) in CTS, occurring with increasing severity of electrophysiologic findings.

Wide-angle lenses and image collapsing subreflectors for nontracking solar collectors.

This paper presents new optical methods for the design of nontracking solar energy concentrators with acceptance angles of 60 degrees in the elevation (altitude) plane and +/-50 degrees in azimuth sectors. We have designed and constructed a two-point corrected cylindrical stepped prism lens (SPL) with 30.48-cm aperture height and F/D congruent with 1, which focuses well over the acceptance interval. Image collapsing subreflector (ICS) surfaces are synthesized that reflect the incident illumination refracted by the lens onto a small fixed absorbing area or shelf ~7.6 cm wide resulting in near maximum theoretical concentration ratios for these broad acceptance angles. Nearly 100% of the incident optical rays intercept the absorber shelf. The wide-angle and image collapsing optical properties were confirmed by laser and solar experiments. Rooftop thermal tests on a 30.5 x 30.5-cm collector section using selectively absorbing tubes with water as circulant were conducted that indicate aperture efficiencies of ~60% could be exected on large area collectors based on this design.

Peripheral neuropathy in young-old and old-old patients.

Diabetes is said to account for most cases of neuropathy in the elderly. We reviewed records of 223 young-old (65-79 years) and 77 old-old (>or=80 years) patients referred for evaluation of neuropathic symptoms over a 9-year period. We prospectively validated our findings in 102 consecutive elderly (77 young-old) patients receiving intensive evaluation for neuropathy. Diabetes was the most common cause of neuropathy (41%), but was less common in the old-old (25% versus 46%, P < 0.001). Idiopathic neuropathies were more common in the old-old (39% versus 9%, P < 0.001). Alcoholic and nutritional neuropathies were uncommon in the old-old. Electrophysiological studies showed that most patients had an axonal type of neuropathy. Sural and peroneal response amplitudes were poorly correlated with age. We obtained similar results in our prospective study. The distribution of causes of neuropathies in young-old and old-old patients, in a hospital-based sample, is age-related. Future studies need to include the old-old to better understand the nature of neuropathy in the elderly.

Median mixed and sensory nerve conduction studies in carpal tunnel syndrome.

OBJECTIVE: To assess the sensitivities and specificities of velocity differences between median mixed nerve conduction across the wrist (Medmxpw) and (I) median mixed nerve conduction in the forearm (Medmxf) and (II) palm to D2 sensory conduction (MedpD2). DESIGN AND METHODS: We prospectively studied 67 limbs of patients with clinically definite carpal tunnel syndrome (CTS). Medmxf and Medmxpw were performed by stimulating the median nerve at the elbow and palm respectively and recording at the proximal wrist crease. We also compared conventional median sensory (D2-wrist) and mixed (palm-wrist) tests in all patients. Thirty limbs of asymptomatic subjects served as normal controls and 21 limbs of subjects with other neuropathies served as diseased controls; control data was collected prospectively. RESULTS: The sensitivity of the MedpD2-Medmxpw difference (0.87) was significantly greater than that of the Medmxf-Medmxpw difference (0.61, P < 0.001). Both tests were similar and highly specific (0.98 and 0.96, respectively). CONCLUSIONS: The MedpD2-Medmxpw study is among the most sensitive and specific electrophysiologic tests for CTS.

Transient worsening of optic neuropathy as a sequela of the Jarisch-Herxheimer reaction in the treatment of Lyme disease.

A 58-year-old woman developed neurologic and neuroophthalmologic manifestations of Lyme disease, including a radiculomyelitis, cranial neuritis and mild right optic neuropathy. Upon treatment with intravenous ceftriaxone a Jarisch-Herxheimer reaction occurred with encephalopathy, mild fever, worsening radiculomyelitis, and deterioration of her visual acuity. Intravenous methylprednisolone was given, and the visual acuity recovered over 72 hours. This case suggests that transient worsening of optic neuropathy can develop as a sequela of the Jarisch-Herxheimer reaction in the treatment of Lyme disease.

Chronic paroxysmal headache: two cases with cerebrovascular disease.

Paroxysmal headaches often occur in benign headache disorders such as episodic cluster headache, chronic paroxysmal hemicrania (CPH) and episodic paroxysmal hemicrania. We report 2 patients with paroxysmal headaches occurring in association with cerebrovascular disease. The first patient had paroxysmal headaches from an arteriovenous malformation which resolved following embolization. In the second patient, headache followed a cerebral infarction and responded to treatment with indomethacin. We suggest that vascular disease may cause paroxysmal headaches resembling CPH. Patients with an atypical presentation of CPH warrant a neuroimaging procedure.

Headache characteristics in hospitalized patients with Lyme disease.

We reviewed 49 patients consecutively hospitalized for neurologic Lyme disease to determine the frequency and characteristics of recent onset headaches in this group. All patients had positive serum Lyme ELISAs and other neurologic illness excluded. Recent-onset headache occurred in 26 of 49 patients (53%). Patients with headaches more commonly had central nervous system involvement (54% vs 19%, P < .05) and flu-like illness (58% vs 19%, P < .0005). Eight of 26 (31%) met criteria for meningitis or encephalitis with abnormal CSF examinations. All 8 had focal findings (6), cognitive dysfunction (1), or both (1). The remaining 18 patients had recent-onset headaches resembling migraine (9), tension-type headache (5), or neither (4). Antibiotic treatment resulted in complete headache resolution in 11 of 14 patients with available follow-up data. Based on these findings, we conclude that recent-onset headaches are common in patients hospitalized with Lyme disease. Of those with meningitis or encephalitis requiring intravenous antibiotics, all had focal neurologic findings or cognitive abnormalities, not just headaches.