Mental disturbances after thalamolysis.

This report concerns two patients, in both of whom the placing of a lesion in the left thalamus, for the purpose of controlling Parkinsonian tremor and rigidity, resulted in a severe and protracted psychic disturbance, characterized by confusion, amnesia, confabulation, and euphoria. One of these patients died, from other causes, nine months after operation. A detailed anatomical and histological examination was carried out on the brain, primarily in order to define the nature and extent of the lesion produced by the balloon-and-cannula technique (Cooper, 1959). The patient was a 57-year-old, normotensive, right-handed man. Over the past 18 years he had gradually developed a severe, and ultimately disabling, tremor of the right hand and arm. More recently, he had suffered from excessive salivation and slowing of gait and of speech. At the time of admission, he was unable to use the right hand for eating, dressing, shaving, or writing. All limbs showed moderate 'cog-wheel' rigidity and there was tremor of the right leg and left arm. He was judged to be of average intelligence, and showed no sign of recent mental impairment or dysphasia. He was said to be naturally shy and retiring, and had been in low spirits for the past year or two. His disability had lost him his job a few months before admission. A left thalamolysis, using Cooper's (1959) technique, was undertaken. The first part of the operation (ventri-culography and placing of the Cooper cannula in the ventrolateral nuclear mass of the thalamus under radiological control, see Fig. 3h) was without incident. When the balloon was inflated with 0 5 ml. of Myodil, the patient instantly shouted 'Stand by, eveiyone in the air-craft' and from that moment was hallucinated, irrational, and inaccessible. At first he was excited, and tried to get down from the operating table in order, as he said, to visit the income tax inspector; later he became drowsy. Over the next few days he became more accessible, but was doubly incontinent and utterly confused as to time and place. At times he failed to recognize his wife and relations, and would deny that he was married. When asked where he was, he gave varied answers: that he was at the factory where he worked, or that he was at the Liverpool Cotton Exchange, where he had worked previously. He fairly consistently gave the date as some time in the 1920s, and his age as …