Deep brain stimulation is now accepted as a safe and efficient treatment for movement disorders including selected types of dystonia and dyskinesia. Very little, however, is known about its effect on other movement disorders, particularly for “choreic” movements. Huntington disease is a fatal autosomal-dominant neurodegenerative disorder characterized by movement disorders, progressive cognitive impairment, and psychiatric symptoms. Bilateral chronic stimulation of the internal globus pallidus was performed to control choreic movements in a 60-year-old man with a 10-year history of Huntington disease. Chronic deep brain stimulation resulted in remarkable improvement of choreic movements. Postoperative improvement was sustained after 4 years of follow-up with a marked improvement in daily quality of life.
Brigitte Biolsi, Laura Cif, Hassan El Fertit, Santiago Gil Robles and Philippe Coubes
Nathalie Vayssiere, Simone Hemm, Michel Zanca, Marie Christine Picot, Alain Bonafe, Laura Cif, Philippe Frerebeau and Philippe Coubes
Object. The actual distortion present in a given series of magnetic resonance (MR) images is difficult to establish. The purpose of this study was to validate an MR imaging—based methodology for stereotactic targeting of the internal globus pallidus during electrode implantation in children in whom general anesthesia had been induced.
Methods. Twelve children (mean follow up 1 year) suffering from generalized dystonia were treated with deep brain stimulation by using a head frame and MR imaging. To analyze the influence of distortions at every step of the procedure, the geometrical characteristics of the frame were first controlled using the localizer as a phantom. Then pre- and postoperative coordinates of fixed anatomical landmarks and electrode positions, both determined with the head frame in place, were statistically compared.
No significant difference was observed between theoretical and measured dimensions of the localizer (Student's t-test, |t| > 2.2 for 12 patients) in the x, y, and z directions.
No significant differences were observed (Wilcoxon paired-sample test) between the following: 1) pre- and postoperative coordinates of the anterior commissure (AC) (Δx = 0.3 ± 0.29 mm and Δy = 0.34 ± 0.32 mm) and posterior commissure (PC) (Δx = 0.15 ± 0.18 mm and Δy = 0.34 ± 0.25 mm); 2) pre- and postoperative AC—PC distance (ΔL = 0.33 ± 0.22 mm); and 3) preoperative target and final electrode position coordinates (Δx = 0.24 ± 0.22 mm; Δy = 0.19 ± 0.16 mm).
Conclusions. In the authors' center, MR imaging distortions did not induce detectable errors during stereotactic surgery in dystonic children. Target localization and electrode implantation could be achieved using MR imaging alone after induction of general anesthesia. The remarkable postoperative improvement in these patients confirmed the accuracy of the procedure (Burke—Marsden—Fahn Dystonia Rating Scale score Δ = −83.8%).