Prospective randomized 1-year follow-up comparison of bilateral subthalamotomy versus bilateral subthalamic stimulation and the combination of both in Parkinson's disease patients: a pilot study.

It has been suggested that potential risk of hemiballismus after subthalamotomy makes DBS preferable to ablation for IPD treatment; however, cost and the need for regular electrode control have also been observed as disadvantages to stimulation. The objective was to compare efficacy and safety of different surgical approaches to STN, in a prospective randomized pilot study. Sixteen consecutive IPD patients randomized to receive either: bilateral STN-DBS, bilateral subthalamotomy or unilateral subthalamotomy plus contralateral STN-DBS implantation, and followed for 12 months after surgery. One patient died and was excluded from the analysis. Total and motor UPDRS scores, as well as drug-induced dyskinesias improved significantly at 1 year follow-up, regardless of the procedure administered and without statistically significant differences between treatment modalities. Discrete changes were observed on ACE and MMSE scores. Psychiatric examination of patients subjected to bilateral stimulation and lesion, revealed slight increment in apathy and irritability scores, coinciding with significant deterioration of mentation, behaviour and mood as measured using the UPDRS. One patient presented persistent hemiballismus and required ulterior posteroventral pallidotomy. In this small group of patients, overall motor performance significantly improved after all three procedures, without major differences in outcome. Adverse events were, nevertheless, observed after both ablation and stimulation. The role of bilateral subthalamotomy in patients unable to receive a DBS electrode-implant merits further exploration in a larger series of patients with longer follow-up.

Bilateral pallidotomy for treatment of Parkinson's disease induced corticobulbar syndrome and psychic akinesia avoidable by globus pallidus lesion combined with contralateral stimulation.

OBJECTIVE: Posteroventral pallidotomy (PVP) has proved to be an effective method for the treatment of Parkinson's disease. However, data on bilateral procedures are still limited. To assess the effects of bilateral globus pallidus (GPi) lesion and to compare it with a combination of unilateral GPi lesion plus contralateral GPi stimulation (PVP+PVS), an open blind randomised trial was designed. METHODS: A prospective series of patients with severe Parkinson's disease refractory to medical treatment, and severe drug induced dyskinesias, were randomised either to simultaneous bilateral PVP or simultaneous PVP+PVS. All patients were assessed with the core assessment programme for intracerebral transplantation (CAPIT), and a comprehensive neuropsychological and neuropsychiatric battery both before surgery and 3 months later. RESULTS: The severe adverse effects found in the first three patients subjected to bilateral PVP led to discontinuation of the protocol. All three patients developed depression and apathy. Speech, salivation, and swallowing, as well as freezing, walking, and falling, dramatically worsened. By contrast, all three patients undergoing PVP+PVS had a significant motor improvement. CONCLUSION: Bilateral simultaneous lesions within the GPi may produce severe motor and psychiatric complications. On the other hand, a combination of PVP+ PVS significantly improves parkinsonian symptoms not associated with the side effects elicited by bilateral lesions.

GPi firing rate modification during beginning-of-dose motor deterioration following acute administration of apomorphine.

We present a patient with clinically evident beginning-of-dose motor deterioration who had undergone posteroventral pallidotomy. This patient underwent an intrasurgical apomorphine test followed by single cell recording of the internal globus pallidus (GPi) to determine changes in GPi firing rate during the occurrence of such phenomenon. A significant increase in GPi firing rate coincident with worsening of patient disabilities prior to improvement was found. This finding suggests that beginning-of-dose motor deterioration may be mediated by enhanced thalamic inhibition.

Unilateral radiofrequency lesion versus electrostimulation of posteroventral pallidum: a prospective randomized comparison.

Microelectrode-guided posteroventral pallidotomy (PVP) has shown to be an effective method in the treatment of a group of patients with advanced Parkinson's disease. A nonlesioning approach by means of deep brain electrodes connected to a programmable neuropacemaker has also been used to inhibit the internal segment of globus pallidus (posteroventral stimulation [PVS]) reporting comparable clinical efficacy to the one obtained with the ablative method. Nevertheless, no controlled studies have been performed to compare the efficacy of both procedures. A prospective series of 13 patients with a clinical indication for globus pallidus surgery was randomized either to a pallidotomy or stimulator implantation, and comparisons on motor and neuropsychologic measurements were made on a 3-month follow-up basis. Primary measurements of efficacy showed a comparable effect on Unified Parkinson's Disease Rating Scale and activities of daily living score after both procedures. Secondary measurements of efficacy showed that although both techniques improve hand tapping score and dyskinesia score, the bilateral improvement in the former was greater after PVS whereas the latter improved more significantly after PVP. No significant changes in neuropsychologic parameters were observed after either PVP or PVS. Side effects and surgery complications occurred in six of 13 patients (three after PVP and three after PVS): they were mild, transient, and unrelated to optic tract injury. In conclusion, the short-time effect and safety of both procedures is comparable.

Anosognosia in patients with cerebrovascular lesions. A study of causative factors.

BACKGROUND AND PURPOSE: Psychological and biological hypotheses have been proposed to explain anosognosia. We correlated the presence of anosognosia with the presence and severity of psychiatric disturbances, neglect, intellectual impairments, and computed tomographic evidence of lesion size, location, and measurements of brain atrophy. METHODS: A series of 80 patients with acute stroke were assessed using a battery of psychiatric and neuropsychological tests and computed tomography. RESULTS: There were five main findings. First, 27 (28%) of the 96 patients originally screened showed anosognosia. Second, patients with anosognosia had significantly higher frequencies of hemispatial neglect and related phenomena, as well as deficits in recognizing facial emotions and in receptive prosody. Third, depression was equally frequent among patients with and without anosognosia. Fourth, patients with anosognosia had a significantly higher frequency of right hemisphere lesions, primarily involving the temporoparietal junction, thalamus, and basal ganglia. Fifth, patients with anosognosia showed significantly more subcortical brain atrophy, primarily involving the frontal white matter and diencephalic areas. CONCLUSIONS: The present study demonstrates that anosognosia does not "protect" stroke patients from depressive feelings; rather, it represents arousal-attentional disorders after lesions in specific areas of the right hemisphere in nonaphasic patients with preexisting subcortical atrophy.

Gyratory epilepsy in a patient with a thalamic neoplasm.

A patient with a right thalamic oligodendroglioma developed seizures characterized by circling behavior, speech arrest, and secondarily generalized seizures. Gyratory epilepsy is relatively uncommon and may either represent a benign form of primary generalized epilepsy or occur secondary to a focal cortical lesion. Thalamic stimulation has been shown experimentally to induce circling movements, but no other clinical cases with a thalamic lesion have been described.