Gamma knife thalamotomy for disabling tremor: a blinded evaluation.
ABSTRACT Gamma knife thalamotomy (GKT) has been used as a therapeutic option for patients with disabling tremor refractory to medications. Impressive improvement of tremor has been reported in the neurosurgical literature, but the reliability of such data has been questioned.
To prospectively evaluate clinical outcomes after GKT for disabling tremor with blinded assessments.
Prospective study with blinded independent neurologic evaluations.
Consecutive patients who underwent unilateral GKT for essential tremor and Parkinson disease tremor at our center. These patients were unwilling or deemed unsuitable candidates for deep brain stimulation or other surgical procedures.
Unilateral GKT and regular follow-up evaluations for up to 30 months, with blinded video evaluations by a movement disorders neurologist.
Clinical outcomes, as measured by the Fahn-Tolosa-Marin Tremor Rating Scale and activities of daily living scores, and incidence of adverse events.
From September 1, 2006, to November 30, 2008, 18 patients underwent unilateral GKT for essential tremor and Parkinson disease tremor at our center. Videos for 14 patients (11 with essential tremor, 3 with Parkinson disease tremor) with at least 6 months' postoperative follow-up were available for analysis (mean [SD] follow-up duration, 19.2 [7.3] months; range, 7-30 months). The Fahn-Tolosa-Marin Tremor Rating Scale activities of daily living scores improved significantly after GKT (P = .03; median and mean change scores, 2.5 and 2.7 points, respectively [range of scale was 0-27]), but there was no significant improvement in other Fahn-Tolosa-Marin Tremor Rating Scale items (P = .53 for resting tremor, P = .24 for postural tremor, P = .62 for action tremor, P = .40 for drawing, P > .99 for pouring water, P = .89 for head tremor). Handwriting and Unified Parkinson's Disease Rating Scale activities of daily living scores tended to improve (P = .07 and .11, respectively). Three patients developed delayed neurologic adverse events.
Overall, we found that GKT provided only modest antitremor efficacy. Of the 2 patients with essential tremor who experienced marked improvement in tremor, 1 subsequently experienced a serious adverse event. Further prospective studies with careful neurologic evaluation of outcomes are necessary before GKT can be recommended for disabling tremor on a routine clinical basis.
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ABSTRACT: Medication is the predominant method for the management of patients with movement disorders. However, there is a fraction of patients who experience limited relief from pharmaceuticals or experience bothersome side-effects of the drugs. Deep brain stimulation (DBS) and surgical lesioning of the thalamus and basal ganglia are respected neurosurgical procedures, with valued success rates and a very low incidence of complications. Despite these positive outcomes, DBS and surgical lesioning procedures are contraindicated for some patients. Stereotactic radiosurgery with the Gamma Knife (GK) has been used as a lesioning technique for patients seeking a non-invasive treatment alternative and for medication-intolerable patients, who are unable to undergo DBS or lesioning due to comorbid medical conditions. Tremors of various etiologies are treated using GK thalamotomy, which targets the ventralis intermedius nucleus. GK thalamotomy produces favorable outcomes when treating tremors, with success rates ranging from 80-100%. In contrast, GK pallidotomy targets the internal globus pallidus, and is used in treating bradykinesia, rigidity, and dyskinesia. Although radiosurgery has proven beneficial for tremors, radiosurgical pallidotomy for bradykinesia, rigidity, and dyskinesia remains questionable, with mixed success rates in the literature that ranges from 0-87%. We suggest that GK thalamotomy be offered along with other neurosurgical approaches as a feasible treatment option to patients who prefer the non-invasive nature of radiosurgery and to those who are unqualified candidates for the neurosurgical alternatives. Also, we advise that patients with bradykinesia, rigidity, and dyskinesia be educated about the variability in the literature pertaining to GK pallidotomy before proceeding with treatment.World Journal of Surgical Oncology 07/2010; 8:61. DOI:10.1186/1477-7819-8-61 · 1.20 Impact Factor
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ABSTRACT: Tremor is a hyperkinetic movement disorder characterized by rhythmic oscillations of one or more body parts. Disease severity ranges from mild to severe with various degrees of impact on quality of life. Essential tremor and parkinsonian tremor are the most common etiologic subtypes. Treatment may be challenging; although several drugs are available, response may be unsatisfactory. For some tremor forms, controlled data are scarce or completely missing and treatment is often based on anecdotal evidence. In this article, we review the current literature on tremor treatment, with a focus on common forms. Copyright © 2015 Elsevier Inc. All rights reserved.Neurologic Clinics 02/2015; 33(1):57-75. DOI:10.1016/j.ncl.2014.09.005 · 1.61 Impact Factor
Article: Tremori[Show abstract] [Hide abstract]
ABSTRACT: La classificazione dei tremori adottata è clinica, arricchita dall’esperienza acquisita dagli autori con l’aiuto dell’elettromiografia poligrafica di superficie. Noi precisiamo il termine di azione che ricopre due sensi: quello di attività muscolare, nel qual caso tutti i tremori che non sono a riposo sono di azione, e quello che significa movimento; il termine di azione si applica, allora, ai tremori prossimali di grande ampiezza. È necessaria l’analisi della localizzazione segmentaria del tremore all’arto superiore. I tremori di localizzazione distale sono rapidi e si osservano generalmente nella postura mantenuta, mentre quelli della radice sono ampi e lenti e si manifestano nel movimento e nel gesto intenzionale. È, a volte, difficile distinguere tra i tremori di azione e le oscillazioni cerebellari di adattamento su un bersaglio, che aumentano con la velocità del movimento. Il tremore cerebellare può essere difficile o impossibile da distinguere dal tremore di Holmes. All’interno di ogni categoria clinica, tremori a riposo, posturali e di azione, sono discusse le eziologie. Il tremore parkinsoniano è opposto al tremore essenziale. Sono sviluppate alcune entità come il tremore di utilizzo strumentale, il tremore corticale e il tremore ortostatico. A proposito del tremore psicogeno, mostreremo il ruolo della registrazione elettromiografica per raccogliere gli elementi obiettivi di diagnosi positiva e ottenere un documento trasmissibile, che dovrebbe permettere di prendere delle decisioni terapeutiche salde e condivise. Affronteremo, inoltre, la fisiopatologia dei tremori fisiologico, parkinsoniano, essenziale e di Holmes. La storia dei bersagli stereotassici accompagna il cammino delle idee fisiopatologiche.02/2014; 14(1):1–17. DOI:10.1016/S1634-7072(14)66663-0