Phosphoglycerate mutase deficiency with tubular aggregates in a patient from Panama.

Introduction: Phosphoglycerate mutase deficiency (PGAM) is a rare metabolic myopathy that results in terminal block in glycogenolysis. Clinically, patients with PGAM deficiency are asymptomatic, except when they engage in brief, strenuous efforts, which may trigger myalgias, cramps, muscle necrosis, and myoglobinuria. An unusual pathologic feature of PGAM deficiency is the association with tubular aggregates.

Role of activity-dependent conduction block in the diagnosis of primary demyelinating polyneuropathy.

Motor conduction block is one of the well-known neurophysiologic features of primary demyelinating polyneuropathy. In contrast, activity-dependent conduction block (motor conduction block after brief maximum voluntary contraction) is a "rare" neurophysiologic finding in primary demyelinating polyneuropathy. We are reporting the first known case of multifocal acquired demyelinating sensory and motor polyneuropathy with a well-documented activity-dependent conduction block of the ulnar nerve at the forearm segment that transformed into a typical motor response with abnormal temporal dispersion.

Intraoperative laryngeal electromyography in children with vocal fold immobility: results of a multicenter longitudinal study.

Objectives: To determine whether laryngeal electromyography (LEMG) can predict recurrent laryngeal nerve function return in children and whether LEMG can aid in the management of vocal fold immobility (VFI).

Design: Prospective case series.

Setting: Tertiary pediatric aerodigestive centers.

Spontaneous and evoked laryngeal electromyography of the thyroarytenoid muscles: a canine model for intraoperative recurrent laryngeal nerve monitoring.

Objectives: We sought to determine the feasibility of performing spontaneous and evoked intraoperative laryngeal electromyography (L-EMG) using nerve monitoring equipment and to compare recording electrode configurations and methods of recurrent laryngeal nerve (RLN) stimulation in dogs.

Methods: Four beagles underwent crush injury of the left RLN, and 2 beagles underwent left RLN transection. Serial spontaneous and evoked L-EMG was recorded with the NIM-Response nerve monitoring system under sedation.

Serial electromyography of the thyroarytenoid muscles using the NIM-response system in a canine model of vocal fold paralysis.

Objectives: We sought to determine whether serial intraoperative laryngeal electromyography (L-EMG) or evoked L-EMG predicts vocal fold (VF) recovery following iatrogenic injury.

Methods: Six beagles were sedated, and bipolar needle electrodes were inserted into each thyroarytenoid (TA) muscle. Endotracheal tube surface electrodes were also placed.

Relapsing Guillain Barré Syndrome and nephrotic syndrome secondary to focal segmental glomerulosclerosis.

A 49-year-old man developed simultaneously a Guillain Barré Syndrome (GBS) and a nephrotic syndrome (NS). The patient relapsed twice, despite treatment with intravenous immunoglobulins (IVIg) after a full or partial recovery, and became resistant to IVIg. Renal biopsy revealed focal segmental glomerulosclerosis (FSGS).

Intraoperative laryngeal electromyography in children with vocal fold immobility: a simplified technique.

Objectives: The primary objective of this study was to determine whether a simplified technique for intraoperative laryngeal electromyography was feasible using standard nerve integrity monitoring electrodes and audiovisual digital recording equipment. Our secondary objective was to determine if laryngeal electromyography data provided any additional information that significantly influenced patient management.

Methods: Between February 2006 and February 2007, 10 children referred to our institution with vocal fold immobility underwent intraoperative laryngeal electromyography of the thyroarytenoid muscles.

Multifocal motor neuropathy with conduction block: Distribution of demyelination and axonal degeneration.

Objective: Multifocal motor neuropathy with conduction block (MMN) is an immune-mediated neuropathy, characterized by progressive muscle weakness. Although demyelination is regarded as the underlying pathophysiologic mechanism of MMN, recently, it was reported that different pathophysiologic mechanisms were responsible for disease in the upper and lower limbs. Specifically, demyelination in the upper limbs and axonal loss in the lower limbs.

Acute sensory neuronopathy as the presenting symptom of Sjögren's syndrome.

Sensory neuronopathy associated with Sjögren's syndrome (SS) usually has a subacute or chronic onset. We report the case of a 37-year-old woman who presented with an unusual hyperacute form of SS ganglionopathy. She initially developed paresthesias of her fingertips and rapidly became severely ataxic.

Cervical nerve root stimulation. Part I: technical aspects and normal data.

Objective: Cervical nerve root stimulation (CRS) is a technique of assessing the proximal segments of motor axons destined to upper extremity muscles. Few studies report normal values. The objective was to determine CMAP onset-latencies and CMAP amplitude, area, and duration changes in healthy controls for the abductor pollicis brevis (APB), abductor digiti minimi (ADM), biceps, and riceps muscles.

Multifocal motor neuropathy: decrease in conduction blocks and reinnervation with long-term IVIg.

Background: Multifocal motor neuropathy with conduction blocks (MMNCB) is an immune-mediated motor neuropathy. Previous long-term IV immunoglobulin (IVIg) treatment studies have documented improvement in muscle strength and functional disability but revealed a concomitant increase in acute axonal degeneration (AD) and conduction block (CB).

Objective: To determine the long-term effects of IVIg therapy on clinical and neurophysiologic outcome measures in MMNCB patients responsive to IVIg.

Neurophysiologic findings in early acute inflammatory demyelinating polyradiculoneuropathy.

Background: Patients with early acute inflammatory demyelinating polyradiculoneuropathy (AIDP) may not meet the current neurophysiologic criteria.

Objective: To document neurophysiologic findings in early AIDP.

Methods: Clinical and neurophysiologic data from 38 AIDP patients, assessed within 10 days of symptom onset were reviewed.

Technology literature review: quantitative sensory testing.

The development of the personal computer has simplified the process of quantitating sensory thresholds using various testing algorithms. We reviewed the technical aspects and reproducibility of different methods to determine threshold for light touch-pressure, vibration, thermal, and pain stimuli. Clinical uses and limitations of quantitative sensory testing (QST) were also reviewed.

Atypical presentations of primary amyloid neuropathy.

Primary amyloidosis (AL) may be complicated by peripheral neuropathy in 15-35% of cases. We report on four patients with atypical neurological presentations of AL neuropathy, whose diagnoses were delayed due to varied clinical presentations. The clinical presentation included painful sensory neuropathy (two patients), mononeuropathy multiplex (one patient), and primary demyelinating polyneuropathy (one patient).