de Preux Mathieu, Precht Christina, Becker Richard, Stieglitz Lennart, Easley Jeremiah, Koch Christoph
Division of Equine Surgery, Swiss Institute of Equine Medicine (ISME), Department of Clinical Veterinary Science, Vetsuisse-Faculty, University of Bern, Bern, Switzerland.
Graduate School for Health Sciences, University of Bern, Bern, Switzerland.
Front Vet Sci. 2025 Jun 13;12:1562404. doi: 10.3389/fvets.2025.1562404. eCollection 2025.
Trigeminal-mediated headshaking is a neuropathic disorder in horses, characterized by signs of regional pain similar to trigeminal neuralgia in humans. The injection of glycerol into the trigeminal cistern to ablate pain-conducting nerve fibers within the trigeminal ganglion -known as glycerol rhizotomy- is a well-established treatment in human medicine. This study compares two approaches to the equine trigeminal cistern using a navigation system for guiding needle placement, a previously described ventral and a newly developed transmandibular lateral approach. The surgical accuracy and risk of iatrogenic collateral damage for the two approaches are assessed.
Five equine cadaveric specimens were used in this study. Magnetic resonance imaging (MRI) of the target region was performed using a 3 T MRI, followed by cone beam computed tomography (CBCT). The two datasets were fused in a surgical navigation system. A trajectory for a ventral navigated approach (VNA) to the trigeminal cistern was planned on one side and for a transmandibular lateral navigated approach (TLNA) on the contralateral side, using the system's planning function. The trigeminal cistern was punctured after introducing the needle along the planned trajectory under real-time navigation guidance, and a toluidine blue solution was injected. A titanium rod was then inserted as a stylet to place a titanium seed within the trigeminal cistern. The rod was left in place to allow artifact-free postprocedural assessment of the surgical trajectory and to measure surgical accuracy aberration (SAA). Prior to dissection, an endoscopic examination was performed to identify any potential perforation of the guttural pouches.
Successful puncture of the trigeminal cistern was achieved in 5/5 specimens via the TLNA, with a median SAA of 3.92 mm (range 3.42 mm - 4.55 mm) and in 3/5 specimens via the VNA, with a median SAA of 6.45 mm (range 2.89 mm - 10.85 mm). The VNA resulted in iatrogenic injury to the internal carotid artery in two cases, and the linguofacial artery in another case. Focal perforation of the mucosa of the guttural pouch was observed in one specimen injected via TLNA.
The TLNA enables accurate and precise minimally invasive puncture of the equine trigeminal cistern in an experimental setting.
三叉神经介导的摇头是马的一种神经病变，其特征是出现与人类三叉神经痛相似的局部疼痛症状。向三叉神经池注射甘油以消融三叉神经节内传导疼痛的神经纤维——即甘油神经根切断术——是人类医学中一种成熟的治疗方法。本研究比较了两种使用导航系统引导针放置的进入马三叉神经池的方法，一种是先前描述的腹侧入路，另一种是新开发的经下颌外侧入路。评估了这两种方法的手术准确性和医源性附带损伤风险。
本研究使用了5个马尸体标本。使用3T磁共振成像（MRI）对目标区域进行扫描，随后进行锥形束计算机断层扫描（CBCT）。将这两个数据集在手术导航系统中融合。利用该系统的规划功能，在一侧规划一条腹侧导航入路（VNA）至三叉神经池的轨迹，在对侧规划一条经下颌外侧导航入路（TLNA）的轨迹。在实时导航引导下，沿规划轨迹插入针后穿刺三叉神经池，并注入甲苯胺蓝溶液。然后插入一根钛棒作为探针，在三叉神经池内放置一颗钛籽。将钛棒留在原位，以便在术后对手术轨迹进行无伪影评估并测量手术准确性偏差（SAA）。在解剖前，进行内镜检查以确定咽鼓管囊是否有任何潜在穿孔。
通过TLNA，5个标本中有5个成功穿刺三叉神经池，SAA中位数为3.92毫米（范围为3.42毫米至4.55毫米）；通过VNA，5个标本中有3个成功穿刺，SAA中位数为6.45毫米（范围为2.89毫米至10.85毫米）。VNA导致2例颈内动脉医源性损伤，1例舌面动脉医源性损伤。在通过TLNA注射的1个标本中观察到咽鼓管囊黏膜的局灶性穿孔。
在实验环境中，TLNA能够准确、精确地对马的三叉神经池进行微创穿刺。
