Fabian Piedimonte

Pallidal surgery for the treatment of primary generalized dystonia: Long-term follow-up

OBJECTIVE To describe the results and long-term follow-up after functional surgery of the internal segment of the globus pallidus (GPi) in 10 patients with primary generalized dystonia. PATIENTS AND METHODS Nine of the 10 patients were positive for the DYT1 gene mutation. Bilateral deep brain stimulation (DBS) of the GPi was performed in three cases, bilateral pallidotomy in two, and combined surgery (unilateral GPi lesion with contralateral stimulation) in the remaining five. All patients were evaluated with the Burke-Fahn-Marsden dystonia scale (BFMDS) before, immediately after surgery, at 3 weeks, 3 and 6 months and then yearly. Follow up time ranged from 15 to 105 months (mean: 66.1 months) with six patients having more than 6 years follow up. RESULTS All patients improved after surgery. All patients with unilateral or bilateral DBS experienced an immediate improvement before starting stimulation. The magnitude of this initial micro lesion effect did not predict the magnitude of the long-term benefit of DBS. The mean decrease in the in the BFMDS was 34%, 55%, and 65% in the movement scale; and 32%, 48%, and 49% in the disability scale for patients with bilateral pallidal DBS, combined unilateral DBS and contralateral pallidotomy, and bilateral pallidotomy, respectively. Worsening of dystonia after a plateau of sustained benefit was observed in three patients. Two patients required multiple pallidal surgeries. Adverse events included: permanent anarthria (1), misplacement of the electrode requiring further surgery (2), scalp infection (1), and hardware related problems (3). CONCLUSIONS This long-term follow up study confirms the beneficial effect of pallidal DBS or pallidotomy in primary generalized dystonia. In addition, our results extent previous observations by showing that, in these patients, (1) the microlesion effect of DBS is not predictive of long-term benefit; (2) combined DBS with contralateral pallidotomy appears to be more effective than bilateral pallidal DBS; and (3) dystonia can reappear after an initial good response during long term follow up.

Beneficial effects of botulinum toxin type A in trigeminal neuralgia

Botulinum toxin has been thoroughly studied as a potential tool in the treatment of several pain syndromes. Therefore, we assessed the clinical effects of botulinum toxin type A injections in 12 patients with otherwise unresponsive idiopathic trigeminal neuralgia. Patients were infiltrated with 20-50 units of botulinum toxin in trigger zones. Those who presented with mandibular involvement were also infiltrated in the masseter muscle. The patients were assessed on a weekly basis using the Visual Analogic Scale for pain. Ten of our patients reported a significant benefit from botulinum toxin injections, with reduction or even disappearance of pain, and remained pain free for as long as 60 days. Our findings suggest that botulinum toxin may represent a useful therapeutic tool in the management of patients with this entity.

Electrical Stimulation of the Inferior Thalamic Peduncle in the Treatment of Major Depression and Obsessive Compulsive Disorders

OBJECTIVE Stimulation of the inferior thalamic peduncle (ITP) is emerging as a promising new therapeutic target in certain psychiatric disorders. The circuitry that includes the nonspecific thalamic system (NSTS), which projects via the ITP to the orbitofrontal cortex (OFC), is involved in the physiopathology of major depression disorder (MDD) and obsessive compulsive disorder (OCD). The safety and efficacy of chronic ITP stimulation in cases of MDD and OCD refractory to medical treatment is presented. MATERIALS AND METHODS Six patients with OCD and one with MDD were implanted with tetrapolar deep brain stimulation electrodes in the ITP (x = 3.5 mm lateral to the ventricular wall, y = 5 mm behind the anterior commissure, and z = at the intercommissural plane, i.e., anterior commissure-posterior commissure [AC-PC] level). The effect of chronic stimulation at 130 Hz, 450 μs, and 5.0 V on OCD was evaluated before and 3, 6, and 12 months after initiation of electrical stimulation through the Yale-Brown Obsessive Compulsive Scale, Hamilton Depression Rating Scale, and Global Assessment of Function scale. RESULTS Chronic ITP electrical stimulation in OCD patients decreased the mean Yale-Brown Obsessive Compulsive Scale score to around 51% for the group at the 12-month follow-up, and increased the mean Global Assessment of Function scale score to 68% for a significant improvement (P = 0.026). Three of 6 patients returned to work. The Hamilton Depression Rating Scale score of the only patient with MDD treated to date went from 42 to 6. This condition of the patient, who had been incapacitated for 5 years prior to surgery, has not relapsed for 9 years. Three OCD patients with drug addiction continued to consume drugs in spite of their improvement in OCD. CONCLUSION Deep brain stimulation in the ITP is safe and may be effective in the treatment of OCD. A multicenter evaluation of the safety and efficacy of ITP in OCD is currently in process.

Micro Lesion Effect of the Globus Pallidus Internus and Outcome with Deep Brain Stimulation in Patients with Parkinson Disease and Dystonia

To determine whether the immediate response to electrode implantation (micro lesion effect, MLE) in the internal segment of the globus pallidus (GPi) predicts symptom improvement with deep brain stimulation (DBS) at 6 months in patients with Parkinsons disease (PD) or generalized dystonia. Electrode implantation in the subthalamic nucleus (STN) prior to electrical stimulation has been reported to predict a beneficial effect of DBS in patients with PD, but whether this is also the case for the GPi in either PD or dystonia patients has not been established. We studied 20 patients (11 with PD and 9 with dystonia) who underwent electrode implantation in the GPi. Effects were assessed using standardized scales after 24 hours, weekly for 3 weeks prior to starting DBS, and after 6 months of DBS. 10 of 11 PD and 8 of 9 dystonia cases who benefited from electrode implantation also showed improvement in all motor and disability scores after 6 months of DBS of the GPi. One dystonia patient who did not show MLE benefited from DBS. The presence of MLE after electrode implantation in the GPi may help predict motor benefit from DBS in PD and generalized dystonia patients.

Behavioral and Motor Improvement After Deep Brain Stimulation of the Globus Pallidus Externus in a Case of Tourette's Syndrome

The objective of our paper is to show the partial decrease of therapeutic effect with battery exhaustion in a previously successfully treated patient with refractory Tourettes syndrome (TS).

Acute Treatment of Trigeminal Neuralgia With Onabotulinum Toxin A

AbstractA double-blind, randomized, placebo-controlled study of patients with essential trigeminal neuralgia and treatment with a single injection of onabotulinum toxin A (BTX) was carried out. The efficacy, safety, and tolerability of either 1 mL 0.9% saline plus 50 U of BTX or only 1 mL of 0.9% saline injected subcutaneously in the affected area were evaluated. Cases with involvement of the third branch of the trigeminal nerve also received intramuscularly either 10 U of BTX or matching placebo in the masseter muscle, ipsilateral to the pain location. Pain was assessed with the visual analog scale (VAS). Twenty subjects were administered BTX, and 16 subjects received placebo. Two months after the intervention, a trend to statistical significance was observed for the VAS mean values in subjects treated with BTX and those who received placebo (VAS 4.9 vs 6.63, t test, P = 0.07). Three months after the injection, significant differences were observed in the average VAS score for subjects treated with BTX and those treated with placebo (VAS 4.75 vs 6.94, respectively; t test, P = 0.01). Onabotulinum toxin A was well tolerated and seems to be a safe and useful therapy for patients with essential trigeminal neuralgia.

Remarkable Clinical Improvement with Bilateral Globus Pallidus Internus Deep Brain Stimulation in a Case of Lesch-Nyhan Disease: Five-Year Follow-Up

Lesch–Nyhan disease (LND) is a hereditary disorder characterized by hyperuricemia, self‐mutilation, developmental retardation, and movement disorders such as spasticity and dystonia. The lack of a precise understanding of the neurological dysfunction has precluded the development of useful conservative therapies. We present our experience treating a LND patient by bilateral globus pallidus internus (GPi) deep brain stimulation (DBS) with improvement in dystonia symptoms and disappearance of self‐injurious behavior.

Posterior Spinal Cord Stimulation in a Case of Painful Legs and Moving Toes

A 59-year-old woman with a 5-year history of right lower limb pain is reported. Symptoms developed initially when walking and progressively became bilateral, appeared at rest and involuntary movements of the toes became evident. A diagnosis of painful legs and moving toes was made. As several drug therapies proved unsuccessful, a therapeutic test with a tetrapolar epidural lead to stimulate the spinal cord dorsal tracts was performed. Due to the marked improvement the device and generator were implanted and she has responded satisfactorily to this therapy for the past 13 months.