Anatomical location of effective deep brain stimulation electrodes in chronic cluster headache

Abstract

Deep brain stimulation of the posterior hypothalamus is a therapeutic approach to the treatment of refractory chronic cluster headache, but the precise anatomical location of the electrode contacts has not been clearly assessed. Our aim was to study the location of the contacts used for chronic stimulation, projecting each contact centre on anatomic atlases. Electrodes were implanted in a series of 10 patients (prospective controlled trial) in the so-called 'posteroinferior hypothalamus' according to previously described coordinates, i.e. 2 mm lateral, 3 mm posterior and 5 mm below the mid-commissural point. The coordinates of the centre of each stimulating contact were measured on postoperative computed tomography or magnetic resonance imaging scans, taking into account the artefact of the electrode. Each contact centre (n=10; left and right hemispheres pooled) was displayed on the Schaltenbrand atlas and a stereotactic three dimensional magnetic resonance imaging atlas (4.7 tesla) of the diencephalon-mesencephalic junction for accurate anatomical location. Of the 10 patients with 1-year follow-up, 5 responded to deep brain stimulation (weekly frequency of attacks decrease >50%). In responders, the mean (standard deviation) coordinates of the contacts were 2.98 (1.16) mm lateral, 3.53 (1.97) mm posterior and 3.31 (1.97) mm below the mid-commissural point. All the effective contacts were located posterior to the hypothalamus. In responders, structures located <2 mm from the centres of effective contacts were: the mesencephalic grey substance (5/5), the red nucleus (4/5), the fascicle retroflexus (4/5), the fascicle longitudinal dorsal (3/5), the nucleus of ansa lenticularis (3/5), the fascicle longitudinal medial (1/5) and the thalamus superficialis medial (1/5). The contact coordinates (Wilcoxon test) and the structures (Fisher's exact test) were not significantly different between responders and non-responders. These findings suggest that failure of deep brain stimulation treatment in cluster headache may be due to factors unrelated to electrode misplacement. They also suggest that the therapeutic effect is probably not related to direct hypothalamic stimulation. Deep brain stimulation might modulate either a local cluster headache generator, located in the hypothalamus or in the mesencephalic grey substance, or non-specific anti-nocioceptive systems.

Neurostimulation in cluster headache: A review of current progress

“…It has been questioned whether the stimulated area, according to the published stereotactic coordinates, indeed is the pHyp or is the adjacent mesencephalic gray. Recently Fontaine et al used the Schaltenbrandt atlas and a stereotactic threedimensional (3D) MRI atlas of the diencephalonmesencephalon junction to precisely pinpoint the electrode in ten hDBS patients who had the implant procedure according to the published coordinates (43). They observed that the hDBS electrodes (both in responders and nonresponders) were located posterior to the mamillary body and mamillo-thalamic fasciculus, usually defined as the caudal border of the hypothalamus.…”

Flexible and stretchable micro-electrodes for in vitro and in vivo neural interfaces

“…They may comprise a single needle bearing multiple contacts on its shaft [20,39] or a 10 9 10 matrix of single contact electrodes [19,36]. Successful penetrating electrodes are already available to humans, e.g., cochlear implants [40] and deep brain stimulator [10,17]. However, stable and long-term recording and stimulation remain a challenge.…”

Long-Term Results of Deep Brain Stimulation of the Mamillotegmental Fasciculus in Chronic Cluster Headache

“…While Leone et al [3] think that DBS stimulates the posterior hypothalamus [3], Meyerson [24] and Burchiel et al [25] suggest that the stimulated volume reaches the periaqueductal gray. Fontaine et al [10] believe that the active contacts are located in a bridging zone between the hypothalamus and the mesencephalic gray matter, and Clelland et al [11] believe that they are located in the gray matter of the mesencephalic tegmentum. Akram et al [23] also place their target at the mesencephalic tegmentum, just anterior to the nucleus ruber.…”