UW Neurological Surgery Recent PubMed Publications

The interdependence of excitation and inhibition for the control of dynamic breathing rhythms.

Nat Commun. 2018 02 26;9(1):843

Authors: Baertsch NA, Baertsch HC, Ramirez JM

Abstract
The preBötzinger Complex (preBötC), a medullary network critical for breathing, relies on excitatory interneurons to generate the inspiratory rhythm. Yet, half of preBötC neurons are inhibitory, and the role of inhibition in rhythmogenesis remains controversial. Using optogenetics and electrophysiology in vitro and in vivo, we demonstrate that the intrinsic excitability of excitatory neurons is reduced following large depolarizing inspiratory bursts. This refractory period limits the preBötC to very slow breathing frequencies. Inhibition integrated within the network is required to prevent overexcitation of preBötC neurons, thereby regulating the refractory period and allowing rapid breathing. In vivo, sensory feedback inhibition also regulates the refractory period, and in slowly breathing mice with sensory feedback removed, activity of inhibitory, but not excitatory, neurons restores breathing to physiological frequencies. We conclude that excitation and inhibition are interdependent for the breathing rhythm, because inhibition permits physiological preBötC bursting by controlling refractory properties of excitatory neurons.

PMID: 29483589 [PubMed - indexed for MEDLINE]

Lawful physician-hastened death: AAN position statement.

Neurology. 2018 02 27;90(9):420-422

Authors: Russell JA, Epstein LG, Bonnie RJ, Conwit R, Graf WD, Kirschen M, Kurek JA, Larriviere DG, Pascuzzi RM, Rizzo M, Sattin JA, Simmons Z, Taylor L, Tsou A, Williams MA, Ethics, Law, and Humanities Committee (a joint committee of the AAN, ANA, and CNS), Ethics, Law and Humanities Committee, a joint committee of the AAN, ANA and CNS

PMID: 29483313 [PubMed - indexed for MEDLINE]

Endovascular stent-coiling of a giant basilar artery aneurysm through a previous radial artery bypass.

J Clin Neurosci. 2018 May;51:100-102

Authors: Ozdemir B, Kelly CM, Levitt MR, Kim LJ

Abstract
Giant, partially-thrombosed basilar artery (BA) aneurysms are extraordinarily difficult to treat. Due to the high risk of rupture exclusion of these aneurysms from the circulation is imperative. In certain instances, direct clipping is unsuitable, and high-flow bypass and proximal parent vessel clip occlusion is required. We report a case of a recurrent partially-thrombosed giant BA apex aneurysm treated with endovascular stent-coiling through a previous radial artery bypass graft. Following the initial bypass and aneurysm trapping six years prior, the patient was neurologically stable until three months prior to admission when he developed new diplopia and left third nerve palsy. Imaging studies demonstrated interval enlargement of the thrombosed portion of the aneurysm and increased size in the filling portion of the aneurysm. In the present case, the existing radial artery bypass graft between left VA and left PCA permitted successful stent-assisted embolization of the recurrent BA aneurysm. To our knowledge, this is the first published case of endovascular stent-coiling of a BA aneurysm through a radial artery bypass graft. This novel technique can be a useful alternative for endovascular aneurysm treatment in these challenging lesions.

PMID: 29483014 [PubMed - indexed for MEDLINE]