Selective Posterior Callosotomy for Treatment of Epileptic Drop Attacks: Video Documentation of the Surgical Technique: 2-Dimensional Operative Video.

This is a surgical technique video of selective posterior callosotomy (SPC), a novel surgical procedure to alleviate refractory epileptic drop attacks.1 Departing from traditional approaches aiming the anterior half or the entire callosum, SPC sections the posterior half of the callosum sparing prefrontal connectivity.1 Drop attacks are generalized epileptic seizures characterized by sudden falls.1 These seizures are often seen in diffuse brain pathology associated with generalized or multifocal epilepsies, whose electroencephalogram (EEG) "fingerprint" is bilaterally synchronous epileptic discharges.1 Sectioning the callosum to control drop attacks follows the rationale that the rapid synchronization of discharges between motor and premotor regions of both hemispheres is the basis.1 The standard approach to callosotomies always contemplated the anterior fibers of the callosum.2 Literature reports that anterior sections lead to unsatisfactory control of drop attacks, and results are improved when extended into a total callosotomy.2,3 This evidence coupled with diffusion tensor imaging (DTI) findings showing that motor and premotor fibers actually cross through posterior half of the callosum led us to hypothesize that selective section of the posterior half of the callosum would section all relevant motor fibers and control drop attacks to a similar extent to total callosotomies, with the advantage of sparing prefrontal interconnectivity3 and no split-brain syndrome. Both our series, one retrospective, followed by a new prospective study have confirmed SPC to be a safe procedure, leading to complete or greater than 90% control of epileptic falls in 85% of patients.1 The video presented here was recorded during a selective posterior callosotomy performed on a 13-yr-old girl who had hundreds of uncontrollable drop attacks per day. Falls were completely controlled with significant gains in psychomotor development and cognition, after 5 yr of follow-up. The patient provided signed consent to the surgical procedure, video acquisition, photo acquisition, and storage at operations, and the publication of this material.

Microsurgical Clipping of Low-Riding Basilar Bifurcation Aneurysm.

Basilar bifurcation is a challenging site for aneurysm clipping. Anatomical factors such as size and projection of the aneurysm, distance between the aneurysm neck and the dorsum sellae, and location of the basilar bifurcation contribute to surgical complexity. Endovascular treatment has been used more frequently than microsurgical clipping, especially for posterior circulation lesions. Thus, the upcoming generation of neurosurgeons will have increasingly less access to the microsurgical treatment of such lesions. We present the case of a 45-year-old female patient who presented sudden mental confusion characterized by disorientation in time, space, and person. Investigative acute cerebral magnetic resonance imaging revealed diffusion restriction in the left posterior cerebral and superior cerebellar arteries. The clinical and cardiologic investigations revealed no abnormalities, but computed tomographic angiography and digital arteriography revealed a low-riding basilar bifurcation aneurysm and a very small aneurysm in the right internal carotid artery. The wide neck precluded coil embolization, and the appropriate stent was not covered by our public health insurance. Considering the young age, surgical treatment was proposed. Microsurgical clipping was performed using the right pre-temporal approach. In this two-dimensional video, we show the steps to reach the low-riding basilar bifurcation aneurysm neck. The positioning, transzygomatic pterional craniotomy, intradural anterior clinoidectomy, and posterior cavernous sinus opening are shown, and the surrounding anatomy is illustrated.