企図振戦に対する定位脳手術の経験

EXPERIENCES OF STEREOTAXIC SURGERY ON THREE IDIOPATHIC INTENTION TREMOR

緒言

　企図振戦は種々の原因により，主として小脳や脳幹部に病変が生じたときに出現する症状であり，この振戦は運動時に出現し目的物に近づくにつれ急速に振幅を増すことが特徴的である。

　企図振戦に対して有効な薬物はなく，1960年Cooper^1）が企図振戦をもった患者に対し，定位脳手術で視床のVL核を破壊することにより，優れた効果を認めている。その後，欧米において可成りの報告がみられるようになり，現在では企図振戦は定位脳手術の適応の1つとなつてきた。

Intention tremor is a symptom caused by den-tatorubrothalamic tract disorder due to various causes and in 1960 Cooper reported that stereo-taxic VL-thalamotomy was effective for intention tremor associated with various kinds of diseases. The same reports as this have been made by other authers since. We also performed a stereotaxic operation on three cases of idiopathic intention tremor, which will be reported briefly.

The cases examined were 2 females and 1 male ranging in age from 32 years to 58 years, and in their familial and clinical histories no episode was found which seemed to have some relation with the intention tremor. Its onset was about 10 to 19 years age.

The intention tremor appeared in any cases on the upper limbs and on the neck, which was evident especially on the right upper limb with a frequncy of 3-5 c/s. However, neither cerebeller signs nor positive neurological findings were confirmed. The PEG, VAG, CAG, and EEG were all within normal limits.

In 2 out of these 3 cases, the tremor on the right upper limb disappeared completely throughthe destruction of the posterior portion of VL and V. im. in the left thalamus and of their adjacent subthalamic area, and at the same time the tremor on the neck was also resolved almost completely. This state is now treserved for 6 to 11 months.

In the remaining one case, the same operation as in the former 2 cases was conducted on both sides. The tremor of both limbs and neck stopped completely, but the dysarthria remained moderately. The patient was doing well 15 months later.

It may by concluded clinically that the destruc-tion of the posterior portion of VL and V.im. and of their adjacent subthalamic area is effective for intention tremor.