Objective: Cervical nerve root stimulation (CRS) allows the assessment of conduction in the proximal segments of motor fibers destined to the upper extremities, which are not evaluated by routine nerve conduction stud...Objective: Cervical nerve root stimulation (CRS) allows the assessment of conduction in the proximal segments of motor fibers destined to the upper extremities, which are not evaluated by routine nerve conduction studies (NCS). Since many primary demyelinating polyneuropathies (PDP) are multifocal lesions may be confined to the proximal nerve segments. CRS may therefore increase the yield of neurophysiologic studies in diagnosing PDP. Methods: We reviewed clinical and neurophysiologic data from 38 PDP patients and compared them to 35 patients with motor neuron disease (MND), and 21 healthy controls (HC). Results: Mean onset-latency was significantly prolonged in PDP patients. The optimal onset-latency cutoff necessary to distinguish PDP from MND and controls was 17.5 ms for the abductor pollicis brevis (APB) and abductor digiti minimi (ADM), and 7 ms for Biceps and Triceps. Mean reduction in proximal to distal CMAP amplitude to APB and ADM was significantly greater in PDP patients, with an optimal cutoff in proximal to distal CMAP amplitude reduction necessary to distinguish PDP from MND and HC being 45%. Conclusions: CRS is effective in distinguishing PDP from MND and HC based on prolonged onset latency and conduction block criteria. Significance: CRS may increase the diagnostic yield in cases where demyelinating lesions are confined to the proximal peripheral neuraxis.展开更多
Background: Multifocal motor neuropathy with conduction blocks (MMNCB) is an i mmune mediated motor neuropathy. Previous long term IV immunoglobulin (IVIg) t reatment studies have documented improvement in muscle stre...Background: Multifocal motor neuropathy with conduction blocks (MMNCB) is an i mmune mediated motor neuropathy. Previous long term IV immunoglobulin (IVIg) t reatment studies have documented improvement in muscle strength and functional d isability but revealed a concomitant increase in acute axonal degeneration (AD) and conduction block (B). Objective: To determine the long term effects of IVIg therapy on clinical and neurophysiologic outcome measures in MMNCB patients res ponsive to IVIg. Methods: The authors reviewed medical records of 10 patients wi th MMNCB for outcomes in muscle strength (Medical Research Council score), funct ional disability (Modified Rankin Disability score), CB, and AD. All patients ha d received IVIg (2g/kg in 5 days for 3 consecutive months), followed by monthly maintenance therapy. Results: Patients were followed for an average of 7.25 year s (range, 3.5 to 12 years). There was significant and sustained improvement in m uscle strength and functional disability while on IVIg therapy. Furthermore, the authors found significant improvement in CB, decrease in AD, and evidence of re innervation by the end of the follow up period. Conclusion: Long term IV immun oglobulin therapy improves muscle strength and functional disability, decreases the number of conduction blocks and the extent of axonal degeneration, and promo tes reinnervation. These findings differ from previous reports of deterioration in neurophysiologic outcome measures. Comparison of the IV immunoglobulin regime n in those reports and this study shows that the authorspatients were treated with significantly higher IV immunoglobulin maintenance doses. These findings ha ve implications for the long term treatment of patients with multifocal motor n europathy with conduction blocks.展开更多
文摘Objective: Cervical nerve root stimulation (CRS) allows the assessment of conduction in the proximal segments of motor fibers destined to the upper extremities, which are not evaluated by routine nerve conduction studies (NCS). Since many primary demyelinating polyneuropathies (PDP) are multifocal lesions may be confined to the proximal nerve segments. CRS may therefore increase the yield of neurophysiologic studies in diagnosing PDP. Methods: We reviewed clinical and neurophysiologic data from 38 PDP patients and compared them to 35 patients with motor neuron disease (MND), and 21 healthy controls (HC). Results: Mean onset-latency was significantly prolonged in PDP patients. The optimal onset-latency cutoff necessary to distinguish PDP from MND and controls was 17.5 ms for the abductor pollicis brevis (APB) and abductor digiti minimi (ADM), and 7 ms for Biceps and Triceps. Mean reduction in proximal to distal CMAP amplitude to APB and ADM was significantly greater in PDP patients, with an optimal cutoff in proximal to distal CMAP amplitude reduction necessary to distinguish PDP from MND and HC being 45%. Conclusions: CRS is effective in distinguishing PDP from MND and HC based on prolonged onset latency and conduction block criteria. Significance: CRS may increase the diagnostic yield in cases where demyelinating lesions are confined to the proximal peripheral neuraxis.
文摘Background: Multifocal motor neuropathy with conduction blocks (MMNCB) is an i mmune mediated motor neuropathy. Previous long term IV immunoglobulin (IVIg) t reatment studies have documented improvement in muscle strength and functional d isability but revealed a concomitant increase in acute axonal degeneration (AD) and conduction block (B). Objective: To determine the long term effects of IVIg therapy on clinical and neurophysiologic outcome measures in MMNCB patients res ponsive to IVIg. Methods: The authors reviewed medical records of 10 patients wi th MMNCB for outcomes in muscle strength (Medical Research Council score), funct ional disability (Modified Rankin Disability score), CB, and AD. All patients ha d received IVIg (2g/kg in 5 days for 3 consecutive months), followed by monthly maintenance therapy. Results: Patients were followed for an average of 7.25 year s (range, 3.5 to 12 years). There was significant and sustained improvement in m uscle strength and functional disability while on IVIg therapy. Furthermore, the authors found significant improvement in CB, decrease in AD, and evidence of re innervation by the end of the follow up period. Conclusion: Long term IV immun oglobulin therapy improves muscle strength and functional disability, decreases the number of conduction blocks and the extent of axonal degeneration, and promo tes reinnervation. These findings differ from previous reports of deterioration in neurophysiologic outcome measures. Comparison of the IV immunoglobulin regime n in those reports and this study shows that the authorspatients were treated with significantly higher IV immunoglobulin maintenance doses. These findings ha ve implications for the long term treatment of patients with multifocal motor n europathy with conduction blocks.
