Ko-Pei Kao

Intravenous immunoglobulin in the preparation of thymectomy for myasthenia gravis

Objectives – A clinical trial including six patients was conducted to assess the effect of intravenous immunoglobulin (IVIg) in the preparation of thymectomy for patients with myasthenia gravis (MG).

Immunosuppressive Treatment in Lower Motor Neuron Syndrome with Autoantibodies against GM1 Ganglioside

We report the results of immunosuppressive treatment with intravenous cyclophosphamide in 12 patients with lower motor neuron syndrome and elevated titers of serum autoantibodies to GM1 ganglioside. All patients had lower motor neuron dysfunction including proximal or distal weakness, fasciculation and muscle atrophy, but no upper motor neuron dysfunction such as hyperreflexia, spasticity or Babinskis sign. Electrophysiological studies revealed no evidence of conduction block, but EMG findings of acute or chronic denervation in the limbs were present. Serum biochemistry and immunological studies were negative for M protein. After a 6-month follow-up, despite a fall in antibody titer, there was no significant clinical improvement in any of the patients.

Cutaneous reflexes in patients with acute lacunar infarctions

Cutaneous reflex (CR) was measured in 15 patients with acute lacunar stroke and in 15 age- and sex-matched normal subjects. EMG activities were recorded from the first dorsal interosseous muscle with surface electrodes, rectified and averaged. Intensity of the stimulation on the index finger was four times the sensory threshold. Aided by audio- and visual-feedback monitoring, the subjects abducted the index finger. Side-to-side comparison was made on all the subjects. CR abnormalities were found in all of our patients. The early inhibitory (I1) and second excitatory (E2) components were attenuated in 11 of 15 patients. The I1-E2 interpeak amplitude (A2) was significantly reduced in all the patients. Prolonged latency of I1-E2 components was found to be pronounced in six of eight patients with sensory symptoms. Eight patients were followed up 1 month later. By that time, the abnormal CR had reversed to some degree in all of them. CR alternation was still present in two fully recovered patients. Our results implied a thalamic relay in the afferent limb of the CR. CR could be a valuable adjunct for assessing long tract dysfunction and monitoring functional recovery.

Long latency responses in pure sensory stroke due to thalamic infarction

Objectives – Our study was designed to clarify the role of the thalamus in the generation of the electrically elicited long‐latency reflexes (LLR) in voluntarily activated hand muscles. Materials and methods – EMG responses of the thenar muscles were evoked by electrical stimulation of the median nerve at the wrist at motor threshold intensity in 10 patients with acute pure sensory stroke due to thalamic infarction. Concomitant recording of somatosensory evoked potentials (SEPs) was performed. The subjects were asked to steadily abduct the thumb at 20–30% of maximal force against a force transducer. Rectified and averaged EMG activities were recorded. Results – The LLR II was missing completely or significantly attenuated in the majority of the patients (9 of 10), of whom 3 also had delayed latency. Abnormal SEPs were documented in 7 patients (7 of 10). In the follow‐up, 5 patients had partial reversal of LLR II. LLR II was still pathological in 1 fully recovered patient. Conclusion – Our results further confirm the transcortical generation of LLR II and imply that a thalamic relay is present in the afferent limb of the LLR.

Lack of serum neutralizing antibody against poliovirus in patients with juvenile distal spinal muscular atrophy of upper extremities

Serum neutralizing antibodies for type 1, 2 and 3 poliovirus were studied in 15 Chinese patients in Taiwan with juvenile distal spinal muscular atrophy of the upper extremities and 15 age-matched normal subjects. Significantly lower serum antibody titers were found in the study group, suggesting that patients with this chronic focal form of acquired motor neuron disease are, to some degree, immunologically unresponsive to the neutralizing epitope of poliovirus.

Optic neuropathy in a patient with chronic inflammatory demyelinating polyneuropathy.

Optic neuropathy in a patient with chronic inflammatory demyelinating polyneuropathy Chronic inflammatory demyelinating polyneuropathy (CIDP) is a widespread, often patchy, demyelination of the peripheral nervous system (PNS) . Optic neuropathy is a rare manifestation of CIDP. Some sporadic reports have mentioned central nervous system involvement in CIDP.l-4 But the course and prognosis of optic neuropathy related to CIDP are not well documented in the literature. We illustrate the abnormal findings, relapsing course and treatment of optic neuropathy in a patient with CIDP.

Genetic polymorphism and Parkinson's disease in Taiwan: Study of debrisoquine 4-hydroxylase (CYP2D6)

Debrisoquine 4-hydroxylase (CYP2D6) is one of the cytochrome P450 enzyme families that catalyze the breakdown of a variety of exogenous and endogenous compounds. Previous reports have suggested that genetic polymorphisms of debrisoquine 4-hydroxylase are associated with susceptibility to Parkinsons disease (PD) in Caucasians. To determine if CYP2D6 also confers susceptibility to PD in Chinese patients, we carried out a study of genetic association using three polymorphic markers of the CYP2D6 gene, 188C/T, 1934G/A (mutant B), and 4268G/C. No differences of allele or genotype frequencies of these three polymorphisms were detected upon comparison of primary PD patients (n=53) with normal controls (n=94). The 1934A allele (mutant B), which accounts for the majority of poor metabolizers in Caucasians, is extremely rare in Chinese. Our data do not support the suggestion that the CYP2D6 gene is related to PD susceptibility in Chinese.

Lack of cervical paraspinal muscle involvement in juvenile distal spinal muscular atrophy: an electromyographic study on 15 cases.

Electromyography (EMG) of the lower cervical paraspinal muscles was performed in 15 young Chinese males with distal spinal muscular atrophy of the upper extremities. The lack of fibrillation and positive sharp waves in all patients, both in early or active and chronic or steady stages, did not correlate with the EMG status in the affected upper extremity on the same side. This finding is in striking contrast with that in amyotrophic lateral sclerosis.

Effect of stimulation of an upper limb on motor evoked potentials in lower limb muscles to transcranial magnetic stimulation in normal subjects and patients with thalamic infarction

The effects of conditioning stimulation of an upper limb on motor evoked potentials (MEPs) of relaxed muscles in both lower limbs were studied in 7 normal subjects and two patients with left thalamic infarction. A possible mechanism for the Jendrassik maneuver (JM) is that induced proprioceptive input ascends supraspinally to facilitate the descending volleys. In order to mimic the JM with a more controlled influence, we used an electrical conditioning (C) stimulation (4 times sensory threshold) delivered to the left index finger preceding the transcranial (T) magnetic stimulation at C-T intervals of 0-200 ms. The MEP facilitation of bilateral tibialis anterior (TA) and gastrocnemius medialis (GC) was within C-T 70-110 ms. The peak facilitation was at C-T 80 ms for ipsilateral TA (309%) and GC (405%) and at C-T 90 ms for contralateral TA (207%) and GC (283%). In the two thalamic infarction patients with right-sided sensory loss, the facilitation did not occur when the conditioning stimulation was delivered to the affected index finger. Therefore, it is likely that the peripheral volley must be transmitted supraspinally to facilitate MEPs of the lower limbs. This method for studying sensory facilitation is more quantitative and reproducible than the JM and technically better than other previously described methods for somatosensory conditioning.

Bromate intoxication with polyneuropathy.

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