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T Mezaki

Publications and source records attributed to T Mezaki.

At least 19 recordsLinked to original sources
PubMed1999

Combined use of type A and F botulinum toxins for blepharospasm: a double-blind controlled trial.

Type A botulinum toxin has widened its clinical range of applications, but the risk of developing antibodies limits the repeated use of high-dose injection. To minimize the risk, mixing different types of toxin might reduce the antigenic presentation of a specific toxin and associated proteins. At the same time, inhibition of the neuromuscular release process at the multiple sites might potentiate the clinical response or the duration of action. We compared the effectiveness of a mixture of type A and type F botulinum toxins with that of type A or type F toxin alone for treating patients with blepharospasm in a double-blind study. Fifty-four patients had 10 units of toxin injection, a mixture of type A and F toxins (including 5 units of each) on one side and either type A or F toxin on the other side of the orbicularis oculi muscle. Clinical evaluation at 4 and 10 weeks after the injection revealed that the peak clinical effect at 4 weeks was similar among the three preparations. The duration of action of the mixture was intermediate between type A and type F alone, as assessed at 10 weeks, when there was a tendency of conserving the beneficial effect on one eye at the expense of that on the other. Although there was no apparent potentiation of the clinical efficacy, the combination of these different types of toxin might be used for decreasing the risk of antibody development.

Blepharospasm↗
PubMed1999

[The clinical usefulness of high-dose intravenous immunoglobulin therapy for chronic inflammatory demyelinating polyneuropathy and multifocal motor neuropathy].

To explore the optimum dose of intravenous immunoglobulin (i.v.Ig) for treating patients with chronic inflammatory demyelinating polyrneuropathy and multifocal motor neuropathy, we compared the usefulness of i.v.Ig among 3 treatment doses. Fifty-nine patients were randomly divided into three treatment dosage groups: 20 patients for Group I using 50 mg/kg/day x 5 days, 19 patients Group II using 200 mg/kg/day x 5 days, and 20 patients Group III using 400 mg/kg/day x 5 days. We assessed clinically and electrophysiologically the effectiveness of the treatment at 5 weeks after the initial infusion. For patients in Group I and II who had not improved (or worsened) with the first treatment, we gave a one-step larger dose in the second treatment (i.e. 200 mg/kg/day x 5 days for those who had been given 50 mg/kg/day x 5 days, 400 mg/kg/day x 5 days for those who had been given 200 mg/kg/day x 5 days) after more than 9 weeks. We found that 15% of the patients in Group I, 21% in Group II and 60% in Group III improved dose-dependently with the first intravenous immunoglobulin treatment. Seven (47%) of 16 patients in Group I and 4 (40%) of 11 patients in Group II improved after the second treatment with larger doses. Adverse reactions including chill sensation, fever, skin eruption and increase in blood GOT and GPT levels were transient and mild. One patient in Group III developed left hemiparesis showing the small infarction in the right thalamus during the course of the treatment, but the symptom was mild. In conclusion, the high-dose intravenous immunoglobulin therapy (400 mg/kg/day x 5 days) is useful for treating patients with CIDP and MMN, although care must be taken of the risk of causing cerebral infarctions.

Adolescent↗
PubMed1999

[Treatment of hemifacial spasm with type A botulinum toxin (AGN 191622): a dose finding study and the evaluation of clinical effect with electromyography].

Forty-one patients with hemifacial spasm had an injection of type A botulinum toxin (AGN 191622; Allergan Co. Ltd., Irvine, CA). Patients were randomly divided into 3 groups by the injection dose: group L (1 unit; 14 patients), group M (5 units; 14 patients), and group H (10 units; 13 patients). Half of the dose was injected into the orbicularis oculi and the rest into the zygomaticus major muscles on the affected side. The clinical effect and electromyogram were evaluated at 2 weeks after the injection. The clinical benefit was dependent on the injection dose, and group H showed the highest rate of improvement (84.6%). No adverse effect related to the toxin was demonstrated except one patient in group H who showed mild and transient lagophthalmos. For 81.8% of group H patients, the final judgement was "useful" or "very useful", which was 9.1% for group L and 50.0% for group M. On the other hand, electromyography disclosed no consistent dose-finding relationship. We conclude that at least 10 (preferably more) units of botulinum toxin are necessary for effectively treating hemifacial spasm. Electromyography has only limited value for the evaluation of clinical effect.

Botulinum Toxins, Type A↗
PubMed1999

[Torsion dystonia].

Explore the source record for details and available documents.

Botulinum Toxins↗
PubMed1996

[Internal carotid artery occlusion related to seat belt shoulder strap: report of two cases].

Two cases of traumatic internal carotid artery occlusion probably related to the seat belt shoulder strap are reported. Case 1. A 20-year-old woman was driving and was struck on the right front side of her car by another car. There were neither bruises, abrasions on her neck, nor weakness in her extremities. About 4 hours later, she developed left hemiplegia, and CT scan taken on the following day revealed low density areas in the capsulostriatal area on the right. The right carotid angiography revealed occlusion of the internal carotid artery about 3 cm distal to the bifurcation. Case 2. A 43-year-old man was driving and was struck on the front of his car by a hard iron railing. He sustained a sternum fracture, but there was no disturbance of consciousness or paresis of the extremities. His neck was unremarkable externally. About 50 days later, he developed left hemiplegia. CT scan and MRI revealed a massive infarction in the distribution of the right middle cerebral artery territories. The carotid angiography revealed occlusion of the right internal carotid artery about 3 cm distal to the bifurcation. In each cases, the driver was wearing a three-point shoulder seatbelt when the car was struck on the front or on the right front. Previous experimental studies have revealed in these situations the neck is flexed right anteriorly, and then quickly overextended left posteriorly. The overextension of the neck probably injured the intima of the internal carotid artery ipsilateral to the shoulder fixed in the seatbelt, resulting in the subsequent occlusion by a thrombus.

Accidents, Traffic↗
PubMed1996

[Treatment of spasticity with botulinum toxin and muscle afferent block].

Spasticity is partly caused by disinhibition of spinal stretch reflex activity and blocking of the group Ia afferents may improve its clinical symptoms. Since muscle afferent block has been successfully used for treating dystonia, this method may become useful for treating spasticity as well. We injected diluted lidocaine (0.5%, 50 ml/session) and ethanol (5 ml) into thigh adductors (for leg crossing), medial hamstrings (for medial rotation of the leg), quadriceps femoris (for hyperextension of the knee), tibialis posterior and triceps surae muscles (pes equinovarus deformity), biceps brachii and forearm flexors (for flexion deformities of the upper extremity) in 12 patients with spasticity. Although the duration of action was short (< 1 day) at first, it was gradually prolonged to several weeks by repeating the injection every 3-4 days. The final outcome was comparable to that obtained by botulinum toxin injection in the same group of patients. This method may prove its promise as a means of treating spasticity.

Adult↗
PubMed1995

Tonic vibration reflex and muscle afferent block in writer's cramp.

Patients with focal dystonia take advantage of certain cutaneous or proprioceptive sensory inputs to alleviate their symptoms ("sensory trick"). We examined the effects of increasing muscle spindle activity by the tonic vibration reflex maneuver and decreasing it by intramuscular injection of lidocaine. The vibration was applied to the palm or the tendon of forearm muscles in 15 patients with writer's cramp and 15 age-matched normal subjects. In 11 patients, the vibration induced dystonic postures or movements typical of those seen during writing. Normal subjects showed either no response to the vibration or a gradually developing tonic vibration reflex only in the wrist and finger flexors, which produced visible movements with a significantly longer latency (12.5 +/- 6.7 seconds [mean +/- standard deviation]) than what was observed in the patients (2.7 +/- 2.5 seconds, p < 0.0001). Local injection of lidocaine (0.5%, 5-40 ml/muscle) attenuated the tendon reflex with relatively little effect on the M response. Injection into muscles with increased activity produced marked reduction of dystonic movements and significant clinical improvement in 13 patients, whereas injection into the other muscles had no effect. The clinical benefit lasted for 1 to 24 hours after injection. In 13 patients who had additional injections of 10% ethanol, which blocks sodium channels for a longer period than does lidocaine, the duration of action was prolonged to 5 to 21 days. These findings suggest that muscles causing dystonic movements have abnormal sensitivities to vibration at rest and that muscle afferents may play a pivotal role in producing dystonic movements.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Physiological study of cervical dystonia. Task-specific abnormality in contingent negative variation.

To investigate the pathophysiology of dystonia, we recorded contingent negative variation (CNV) in 12 patients with cervical dystonia and in 12 age-matched normal subjects. In a simple reaction time paradigm, the subjects were given a pair of a warning stimulus and a subsequent stimulus that triggered head rotation to either side or extension of the fingers. In normal subjects, CNVs for head rotation were not affected by neck muscle pre-activation simulating torticollis, and were always symmetrical with equally high amplitudes over the frontal and central leads. By contrast, CNVs for finger movement had the maximum over the central lead and showed a characteristic distribution; those for the right finger movement had the left hemisphere dominance, whereas those for the left finger movement had similar amplitudes over both hemispheres. In patients with rotatory torticollis (rotatocollis), the components of CNVs for head rotation were markedly attenuated in all the leads, except for the initial negative deflection (orienting response). As a whole, cervical dystonia patients had significantly lower amplitudes of late CNVs for head rotation than normal subjects (P < 0.001), whereas late CNV amplitudes in finger extension did not differ in the two groups. Their reaction times for head rotation were similar, but durations of EMG activities were prolonged in the patients because of co-contractions of the antagonists. The task-specific CNV amplitude loss is therefore not explained by reaction times or by the abnormal neck muscle activities prior to the movement, but it reflects a failure of neural activities preparing for a phasic neck movement, resulting in co-contraction of the agonists and the antagonist. Dystonia may be associated with defective retrieval or retaining of specific motor programmes or subroutines in response to sensory stimuli.

Adult↗