J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.33.1.7 on 1 February 1970. Downloaded from J. Neurol. Neurosurg. Psychiat., 1970, 33, 7-15 Relief ofintention tremor by thalamic surgery' KHAIRY SAMRA, JOSEPH M. WALTZ, MANUEL RIKLAN, MAXIM KOSLOW, AND IRVING S. COOPER From the Department ofNeiirologic Surgery, St. Barnabas Hospital, Bronx, New York, U.S.A. In 1960, it was first reported by one of us (Cooper, sometimes undergo surgery because of extenuating 1960a) that intention tremor could be relieved by a circumstances. For example, a limited goal might be an surgical lesion placed in the ventrolateral nucleus of attempt to decrease dependence on nursing care through surgical alleviation of the tremor affecting the arm and the thalamus. Since then, a number of reports have hand needed for feeding. appeared in the literature (Cooper, 1960b; Broager Investigative procedures were performed, when and Fog, 1962; Cooper, 1962b; Krayenbuhl and indicated, to determine the aetiology of the intention Yasargil, 1962; Cooper, 1965; Laitinen, 1965; Fox tremor, and included radiographs of the skull, CSF and Kurtzke, 1966), corroborating the therapeutic analysis, EEG, EMG, brain scanning, angiography, value of thalamic surgery for intention tremor. pneumoencephalography, and occasionally cortical It is the purpose of this report to summarize our biopsy. guest. Protected by copyright. results and sequelae of cryothalamectomy, carried 73 consecutive cases of intention tremor of PRE-OPERATIVE STATUS Variables pertinent to pre- out on operative status are shown in Table 1. diverse aetiology. These operations were performed The causes of intention tremor in the present series during the period of 10 August 1966 until 26 July were as follows: familial (26 cases); multiple sclerosis 1968. (25 cases); cerebellar degeneration of unknown origin (seven cases); post-traumatic (five cases); posterior fossa MATERIAL AND METHODS tumour (one case); Leber's disease (one case); and associ- ated with torticollis in two cases and Parkinsonism in The seventy-three patients were examined pre-operatively six cases. Thirty-nine patients were males and 34 were by the investigative team on the neurosurgical service at females. There was male preponderance in the familial St. Barnabas Hospital. In the clinical analysis of the group in contrast with the multiple sclerosis cases. The symptoms, intention tremor was rated on a five-point age incidence varied from 15 to 79 years with a mean of scale, ranging from 0 for absence of the tremor to +4 for 42-3 years. All the patients, except one, were right maximum rating. Pre-and post-operative motion pictures handed. The average duration of the tremor was 17-9 were obtained in each case. In addition, a special objective years with a range of two to 50 years. The tremor was method (Dierssen, Lorenc, and Spitaleri, 1961) of evalu- unilateral in three cases and bilateral in the remaining. ation of individual motion picture frames before and The upper extremities were affected more than the lower; after surgery, provided a measurable index of intention and the right side slightly more than the left. In 13 patients, there was neck tremor in addition to limb tremor. In all tremor (Fig. 1). http://jnnp.bmj.com/ Language and speech assessments were made one to cases, the tremor was severe enough (3+ or more) to three days before surgery, within two weeks after surgery, interfere with the patient's activities. and in some cases during follow-up re-evaluation of As expected, the patients with multiple sclerosis varying periods. demonstrated other neurological deficits such as nystag- Pre-operative psychological data on each patient were mus (eight cases), optic atrophy, cranial nerve palsy, derived from clinical interviews conducted by an ex- dysarthria, spasticity, sensory abnormalities, and sphinc- perienced psychologist. On the basis of these initial teric disturbances. Also, patients with cerebellar degener- interviews each patient was rated on a three-point scale ation of unknown aetiology, showed other cerebellar as a good, fair, or poor candidate for surgery. Usually, signs such as nystagmus (three cases), ataxia (two cases), on September 25, 2021 by patients with 'poor' pre-operative psychological ratings and dysmetria (two cases). did not, and do not, undergo surgery. However, since On the basis of pre-operative psychological evaluation, the decision regarding advisability of surgery must take 41 patients were rated as good, 24 were labelled as fair, into account medical condition, neurological factors, and eight were considered poor candidates for surgery. and other variables, in addition to psychological findings, Medical problems significant from a surgical standpoint some patients with a 'poor' psychological rating may included pre-existing hypertension (five cases), cardiac conditions (three cases), diabetes mellitus (three cases), 'Supported by The John A. Hartford Foundation, Inc., New York. urinary problems (six cases), and epilepsy (two cases). 7 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.33.1.7 on 1 February 1970. Downloaded from 8 Khairy Samra, Joseph M. Waltz, Manuel Riklan, Maxim Koslow, and Irving S. Cooper A PREOPERATIVE -ucN h guest. Protected by copyright. B. POSTOPERATIVE Touch at 1066 msec ... i 1. http://jnnp.bmj.com/ on September 25, 2021 by FIG. 1. Tracing from cinematographic record (technique of Dierssen) to demonstrate spatial and temporal elements of intention tremor. A = before surgery; B = after surgery. Reliefofintention tremor by thalamic surgery 9 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.33.1.7 on 1 February 1970. Downloaded from TABLE 1 CAUSES OF INTENTION TREMOR Aetiology ofIT. Cases Sex Age Duration of Positive Side ofIT. Psychologicalcandidacy (no.) M F (mean) I.T. (mean) family (yr) (yr) history Bilat. Unil. Neck Good Fair Poor Familial cerebellar degeneration 26 18 8 54-4 31-7 26 22 4 5 18 7 1 Multiple sclerosis 25 6 19 32 8-2 2 25 - 5 12 9 4 Idiopathic I.T. 7 4 3 43-4 19-4 5 2 1 3 3 1 Severe head injury 5 5 - 34 4-2 1 4 1 1 3 2 - Post. fossa tumour 1 - 1 15 7 1 - 1 Leber's disease 1 1 - 15 6 1 - 1 - _ 1 I.T. and torticollis 2 1 1 42 12 2 - I.T. and Parkinsonism 6 4 2 62-1 9.3 - 6 - 1 3 2 l Total 73 39 34 42-3 17-9 29 65 8 13 41 24 8 OPERATIVE DATA The surgical procedure of cryothala- posterior, as evidenced by early development of par- mectomy (Cooper, 1962a), was used in all the cases. aesthesia, the second one was placed anterior to it, thus Sixty-four patients had unilateral surgery (49 on the left overlapping the optimum locus. More than one lesion side of the brain and 15 on the right), and nine had was found necessary in 22 cases. bilateral surgery. The time interval between the first and second side surgery was at least six months. In all in- RESULTS stances, the surgical target was the posterior aspect of the ventrolateral nucleus of the thalamus (VL) extending slightly posteriorly to include the adjacent anterior Each of the patients in this series was followed guest. Protected by copyright. portion of ventroposterolateral (VPL) and/or ventro- closely from the time of operation until the time of posteromedial (VPM) nuclei. The two cases of intention this report. tremor associated with torticollis, required additional At the time of discharge from the hospital, 54 lesions in centromedianum (CM). patients showed excellent relief of intention tremor The ventricular landmarks used in determining the on the side for which they underwent surgery; 12 target area are shown in Fig. 2. After identification of the had good relief, and four had mild improvement. target on the ventriculogram, a lesion was created by the The remaining three cases did not show any cryogenic technique. The mean temperature used was benefit from surgery (Table 2). - 90°C for two minutes with a range between - 700 and -1 30°C. If one lesion was insufficient, a second or even It is worth mentioning that 12 patients showed a third lesion was tailored to produce the desired clinical significant improvement in intention tremor of the results; so that if the first lesion was deemed slightly too extremities ipsilateral to the side of operation, in I http://jnnp.bmj.com/ on September 25, 2021 by FIG. 2. Ventricular landmarks used in determining the target area (T). J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.33.1.7 on 1 February 1970. Downloaded from 10 Khairy Samra, Joseph M. Waltz, Manuel Riklan, Maxim Koslow, and Irving S. Cooper TABLE 2 CASE 2 RESULTS OF SURGERY Mrs. B. R., a 35-year old housewife, gave a history con- Aetiology ofLT. Cases Relief No sistent with multiple sclerosis, of 11 years' duration. Her (no.) improve- chief complaint was blurred vision, inability to walk, and Excellent Good Mild ment intention tremor. The patient was admitted to St. Familial cerebellar Barnabas Hospital on 15 January 1968, and examination degeneration 26 22 3 1 - at that time revealed bilateral decrease of visual acuity, Multiple sclerosis 25 13 7 2 3 20/200 pallor of the optic disc more marked on the right Idiopathic I.T. 7 6 - 1 - than the left, horizontal nystagmus, moderate to marked Head injury 5 4 1 - - Post. fossa tumour 1 - 1 - - paresis of both lower limbs, more on the left. Deep Leber's disease 1 1 - - - tendon reflexes were hyperactive on both upperextremities I.T. and torticollis 2 2 - - - and right lower extremity and hypoactive on the left lower I.T. Parkinsonism 6 6 - - - extremity. Other neurological findings were bilateral Total 73 54 12 4 3 Babinski reflexes, hypoalgesia over the left lower limb, and 4+ intention tremor on the right upper limb and 3 + in the left upper limb, with no tremor noted in the lower extremities.