Deep brain stimulation improves survival in severe Parkinson's disease.

OBJECTIVES: Levodopa and other dopaminergic treatments have not had the expected effect on survival in Parkinson's disease (PD). Bilateral subthalamic nucleus deep brain stimulation (STN-DBS) has been shown to improve motor function, motor fluctuations, health-related quality of life, and to reduce medication usage and drug-induced dyskinesia in patients with severe PD refractory to medical therapy. Little however, has been described on the impact of STN-DBS on the survival of these patients. We aim in this study to examine the impact of STN-DBS on the survival of patients with severe PD. METHODS: Patients who were eligible for STN-DBS were given the choice of undergoing surgery or continuing on medical treatment. Those who exercised patient choice and preferred to continue with medical treatment formed a control population. All eligible patients seen in a 10-year period are included in this study. Our primary outcome measure is a difference in mortality between the two groups with a secondary measure of admission rates to residential (nursing home) care. RESULTS: 106 patients underwent STN-DBS, and 41 patients exercised patient choice and declined the procedure. The two groups were matched for age, gender, ethnicity, duration of disease, rates of pre-existing depression and Levodopa equivalent doses of anti-Parkinson's medications taken. Patients undergoing STN-DBS had significantly longer survival and were significantly less likely to be admitted to a residential care home than those managed purely medically. The statistical significance of these findings persisted after adjusting for potential confounding factors (survival: p=0.002, HR 0.29 (0.13 to 0.64) (residential care home admission: OR: 0.1 (95% CI 0.0 to 0.3; p<0.001). INTERPRETATION: We show for the first time that there is a survival advantage of DBS surgery in advanced PD. The effect of potential bias factors is examined. The survival advantage may arise for several postulated reasons, ranging from improvement in axial functions, such as swallowing, to some as yet unrecognised benefit of reduction in dopaminergic medication. These findings are of great interest to both patients with PD and the health professionals considering the treatment options for patients with severe PD.

Unilateral pallidal deep brain stimulation in a patient with dystonia secondary to episodic ataxia type 2.

BACKGROUND/AIMS: This paper describes the use of deep brain stimulation (DBS) of the globus pallidus internus (GPi) in the treatment of secondary dystonia caused by expisodic ataxia type 2 (EA2). METHODS: We present the case of a patient with EA2, an autosomal dominant condition, who developed late-onset cervical and right upper limb segmental dystonia. The patient underwent left GPi DBS. RESULTS: Within 4 months of commencing stimulation of the left GPi, the patient had resolution of his neck pain and was able to keep the head straighter for longer time intervals. There was also improvement in right arm segmental dystonia. There was an improvement in the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS 21.5) of 55% at 4 months and of 51% at 22 months. CONCLUSION: The treatment of secondary dystonia is difficult and the results with GPi DBS are less favourable compared with primary dystonia. This case illustrates the successful treatment of secondary dystonia caused by EA2.

Use of endotracheal tube electrodes in treating glossopharyngeal neuralgia: technical note.

BACKGROUND/AIMS: This paper describes the use of endotracheal tube surface electrodes to help delineate the sensory and motor vagal rootlets which may be sacrificed during the surgical treatment of glossopharyngeal neuralgia. METHODS: Three patients with glossopharyngeal neuralgia were studied. All patients had their procedure under general anesthesia and a nerve integrity monitor electromyography endotracheal tube (Medtronic Xomed, Jacksonville, Fla., USA) was inserted under direct vision by the anesthesiologist. A bipolar stimulating electrode identified which, if any, of the upper rootlets of the vagus nerve caused a motor contraction near the vocal cords (i.e. motor branch) and which did not cause contractions (i.e. sensory branch). Sectioning of the glossopharyngeal and any purely sensory rootlets of the vagus nerve was subsequently performed. RESULTS: All patients had immediate and long-lasting relief of their glossopharyngeal neuralgia. In all 3 patients, use of the bipolar stimulating electrode on the lower vagal rootlets induced a recordable muscle action potential in the region of the vocal cords with low current (<0.2 mA). There were no complications consequent to placement of the nerve integrity monitor endotracheal tube. CONCLUSION: Due to the ease of use and reduced trauma, compared to needle electrodes, we would advocate endotracheal tube surface electrode monitoring in all patients undergoing surgical treatment of their glossopharyngeal neuralgia or any intracranial procedure where the integrity of the vagal nerve is in jeopardy.

Deep brain stimulation of the subthalamic nucleus for advanced Parkinson disease using general anesthesia: long-term results.

OBJECT: The authors analyze long-term outcome in a substantial number of patients who underwent subthalamic nucleus (STN) deep brain stimulation (DBS) surgery under general anesthesia. METHODS: Eighty-two patients underwent bilateral placement of DBS electrodes under general anesthesia for advanced Parkinson disease; the STN was the target in all cases. All patients underwent intraoperative microelectrode recording of the STN. No intraoperative macrostimulation was performed. Unified Parkinson's Disease Rating Scale (UPDRS) data were recorded in 28 patients. Assessment of outcome was performed using the UPDRS (in 28 cases), the electrophysiological recordings (in all 82 cases), medication reduction (in 78 cases), and complications (in 82 cases). RESULTS: There was improvement in UPDRS scores across all measures following surgery. The total UPDRS score, off medication, improved from 68.78 (geometrical mean, 95% CI 61.76-76.60) preoperatively to 45.89 (geometrical mean, 95% CI 34.86-60.41) at 1 year postoperatively (p = 0.003, data available in 26 patients). Improvements were obtained in UPDRS Part II (Activities of Daily Living) off medication (p = 0.001) and also UPDRS Part III (Motor Examination) off medication (p < 0.001). Results for the on-medication and on-stimulation states also showed a statistically significant improvement for UPDRS Part III (p = 0.047). Good microelectrode recording of the STN was obtained under general anesthesia; the median first-track length was 4.0 mm, and the median number of tracks passed per patient was 3.0. The median reduction in levodopa medication was 58.1% (interquartile range 42.9%-73.3%). One patient had an intracerebral hemorrhage in the track of 1 electrode but did not require surgical evacuation. One patient had generalized convulsive seizures 24 hours postoperatively and was intubated for seizure control. Unified Parkinson's Disease Rating Scale scores were obtained in 26 patients at 1 year, 28 patients at 3 years, 17 at 5 years, and 7 at 7 years postoperatively. Up to 7 years postoperatively, there was sustained improvement in the total UPDRS score. The results in these patients showed minimal deterioration in the motor section of the UPDRS over time, up to 7 years following the operation. The authors found no evidence that the UPDRS Part II scores changed significantly over the period of 1-7 years after surgery (p = 0.671, comparison of mean scores at 1 and 7 years using generalized estimating equations). CONCLUSIONS: Long-term outcomes confirm that it is both safe and effective to perform STN DBS under general anesthesia. As part of patient choice, this option should be offered to all DBS candidates with advanced Parkinson disease to enable more of these patients to undergo this beneficial surgery.

Rechargeable internal neural stimulators--is there a problem with efficacy?

INTRODUCTION: With the advent of rechargeable internal neural stimulators (rINS) for deep brain stimulation, our aim was to survey patient satisfaction and clinical efficacy in an early cohort of patients receiving this new technology. METHODS: This is an observational study on nine patients with rINS. All patients had initially received non-rechargeable INS with established efficacy of their deep brain stimulation system for either dystonia or pain. Patient satisfaction and efficacy with their rINS were established by completion of a questionnaire, a quality of life assessment (SF-36), and calculation of the total electrical energy delivered (TEED) by the rINS. RESULTS: A reduction in efficacy of their rINS was noticed in 22% of patients. In 78% of patients, there was a problem with recharging their rINS because of poor contact. Two patients (22%) felt that recharging the rINS interfered with their lives and it was a daily reminder that they had a deep brain stimulator system in situ. Eight out of nine patients (89%), however, would recommend to other patients to have an rINS. CONCLUSION: Most patients were happy with their rechargeable internal neural stimulator. A reduction in efficacy was noticed in 22% of patients, which is similar to the proportion of patients noticing a reduction in efficacy when replacing with a non-rechargeable system. Thus, all patients require close monitoring post-replacement of rINS, in case possible adjustment of parameters is required.

Percutaneous glycerol rhizotomy for trigeminal neuralgia: safety and efficacy of repeat procedures.

Percutaneous glycerol rhizotomy (PGR) is an established technique to treat trigeminal neuralgia. Our aim was to establish how safe and efficacious repeat glycerol rhizotomies were on a study of 179 PGRs performed in our institution. There was an overall success rate of 92.1% in improvement of facial pain. Nine patients had reduced facial sensation post-operatively. There were no cases of anaesthesia dolorosa. The mean time to repeat injection was 22.9 months (1-108 months). Of those requiring repeat glycerol rhizotomies within 6 months, 23% had multiple sclerosis. There was no evidence that the number of repeat glycerol rhizotomies affects the probability of them having a complication (p = 0.87). Glycerol rhizotomy for trigeminal neuralgia is a safe and efficacious method of pain relief, which is particularly useful in the elderly. It can be repeated many times with no increase in morbidity and most importantly, in our practice, no anaesthesia dolorosa.

Haemorrhagic cerebellar fibrous histiocytoma: case report and literature review.

Malignant fibrous histiocytoma is uncommon within the central nervous system. It is a pleomorphic sarcoma originally found in soft tissue(1) and there are few reported cases within the central nervous system, in particular the cerebellum. This tumour is difficult to diagnose and may be difficult to treat. We present a case of cerebellar malignant fibrous histiocytoma, its management and literature review.

Synovial cyst presenting as a C1/2 tumour.

Synovial cysts presenting within the cervical spine are rare. We describe a case of a synovial cyst presenting as a tumour and the successful management.

Resolution of third nerve palsy following treatment of prolactinoma with cabergoline.

This report describes a case of prolactinoma that presented acutely with a third nerve palsy without evidence of apoplexy. The third nerve palsy resolved within 48 h on medical therapy. This is an atypical clinical presentation that highlights a successful and novel medical approach to treatment.