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Facial pain occurs in approximately 80% of patients with head and neck cancers. Pain in these settings may result directly from the tumor, or indirectly as a side effect of oncological treatment of the tumor. Optimizing treatment for cancer pain of the face, therefore, involves a variety of diagnostic and treatment considerations, with the development of a successful treatment algorithm dependent on accurate diagnosis of the anatomical location of the pain, its relationship to the facial pain pathway, the type of pain being treated and, finally, patient's prognosis and preference for treatment modality. Beyond direct treatments to reduce tumor burden, a wide variety of neuro-ablative and neuro-augmentative approaches are available that may be tailored to a patient's specific pain syndrome and individual clinical context, taking into account the patient's treatment goals, life expectancy, other cancer-related medical problems, and end-of-life issues., (© 2020 S. Karger AG, Basel.)

Background: Deep brain stimulation (DBS) is well-established, evidence-based therapy for Parkinson disease, essential tremor, and primary dystonia. Clinical outcome studies have recently shown that "asleep" DBS lead placement, performed using intraoperative imaging with stereotactic accuracy as the surgical endpoint, has motor outcomes comparable to traditional "awake" DBS using microelectrode recording (MER), but with shorter case times and improved speech fluency., Objective: To identify procedural variables in DBS surgery associated with improved surgical efficiency and stereotactic accuracy., Methods: Retrospective review of 323 cases with 546 leads placed (August 2011-October 2014). In 52% (n = 168) of cases, patients were asleep under general anesthesia without MER. Multivariate regression identified independent predictors of reduced surgery time and improved stereotactic accuracy., Results: MER was an independent contributor to increased procedure time (+44 min; P = .03). Stereotactic accuracy was better in asleep patients. Accuracy was improved with frame-based stereotaxy at head of bed 0° vs frameless stereotaxy at head of bed 30°. Improved accuracy was also associated with shorter procedures (r = 0.17; P = .049). Vector errors were evenly distributed around the planned target for the globus pallidus internus, but directionally skewed for the subthalamic (medial-posterior) and ventral intermediate nuclei (medial-anterior)., Conclusion: Distinct procedural variables in DBS surgery are associated with reduced case times and improved stereotactic accuracy., (Copyright © 2018 by the Congress of Neurological Surgeons.)

Objective: Lateral supracerebellar-infratentorial approaches are established for lesions in ambient cistern and posterolateral midbrain, but published surgical experiences do not describe results with this approach in the sitting position. Gravity retraction of the cerebellum opens this surgical corridor and dramatically alters exposure, creating 2 variations of the lateral supracerebellar-infratentorial approach: the supracerebellar-supratrochlear approach and the infratentorial-infratrochlear approach., Methods: We reviewed our experience treating cavernous malformations and arteriovenous malformations (AVMs) of the posteroinferior thalamus and posterolateral midbrain by use of supracerebellar-supratrochlear and infratentorial-infratrochlear approaches. Microsurgical technique, clinical data, radiographic features, and neurological outcomes were evaluated., Results: During an 11-year surgical experience with 341 cavernous malformation patients and 402 AVM patients, 8 patients were identified, 6 with cavernous malformations and 2 with AVMs. Infratentorial-infratrochlear approaches were used in 4 patients (50%), including 3 with inferolateral midbrain cavernous malformations. Supracerebellar-supratrochlear approaches were used in 4 patients (50%), including 2 with posterior thalamic lesions surfacing on pulvinar. Resections were radiographically complete in all cases. There were no new, permanent neurological deficits, nor were there any medical or surgical complications. There has been no evidence of rebleeding or recurrence., Conclusions: Gravity retraction of the cerebellum transforms the lateral supracerebellar-infratentorial approach, enhancing exposure and approach trajectories that can be achieved with patients in prone or lateral positions. The increased upward viewing angle of the supracerebellar-supratrochlear approach accesses the posteroinferior thalamus. The increased downward-viewing angle of the infratentorial-infratrochlear approach accesses cerebellomesencephalic fissure and posterolateral midbrain. These approaches open wide corridors for safe surgical resection of symptomatic cavernous malformations and AVMs.

The subventricular zone (SVZ) is the largest germinal zone in the mature rodent brain, and it continuously produces young neurons that migrate to the olfactory bulb. Neural stem cells in this region generate migratory neuroblasts via highly proliferative transit-amplifying cells. The Wnt/beta-catenin signaling pathway partially regulates the proliferation and neuronal differentiation of neural progenitor cells in the embryonic brain. Here, we studied the role of beta-catenin signaling in the adult mouse SVZ. beta-Catenin-dependent expression of a destabilized form of green fluorescent protein was detected in progenitor cells in the adult SVZ of Axin2-d2EGFP reporter mice. Retrovirus-mediated expression of a stabilized beta-catenin promoted the proliferation of Mash1+ cells and inhibited their differentiation into neuroblasts. Conversely, the expression of Dkk1, an inhibitor of Wnt signaling, reduced the proliferation of Mash1+ cells. In addition, an inhibitor of GSK3 beta promoted the proliferation of Mash1+ cells and increased the number of new neurons in the olfactory bulb 14 days later. These results suggest that beta-catenin signaling plays a role in the proliferation of progenitor cells in the SVZ of the adult mouse brain.