Overton Jacqueline A, Cooke Dylan F, Goldring Adam B, Lucero Steven A, Weatherford Conor, Recanzone Gregg H
Center for Neuroscience, University of California, Davis, California;
Department of Biomedical Physiology and Kinesiology, Simon Fraser University, Burnaby, British Columbia, Canada.
J Neurophysiol. 2017 Dec 1;118(6):3252-3270. doi: 10.1152/jn.00191.2017. Epub 2017 Aug 30.
Traditionally, head fixation devices and recording cylinders have been implanted in nonhuman primates (NHP) using dental acrylic despite several shortcomings associated with acrylic. The use of more biocompatible materials such as titanium and PEEK is becoming more prevalent in NHP research. We describe a cost-effective set of procedures that maximizes the integration of headposts and recording cylinders with the animal's tissues while reducing surgery time. Nine rhesus monkeys were implanted with titanium headposts, and one of these was also implanted with a recording chamber. In each case, a three-dimensional printed replica of the skull was created based on computerized tomography scans. The titanium feet of the headposts were shaped, and the skull thickness was measured preoperatively, reducing surgery time by up to 70%. The recording cylinder was manufactured to conform tightly to the skull, which was fastened to the skull with four screws and remained watertight for 8.5 mo. We quantified the amount of regression of the skin edge at the headpost. We found a large degree of variability in the timing and extent of skin regression that could not be explained by any single recorded factor. However, there was not a single case of bone exposure; although skin retracted from the titanium, skin also remained adhered to the skull adjacent to those regions. The headposts remained fully functional and free of complications for the experimental life of each animal, several of which are still participating in experiments more than 4 yr after implant. Cranial implants are often necessary for performing neurophysiology research with nonhuman primates. We present methods for using three-dimensional printed monkey skulls to form and fabricate acrylic-free implants preoperatively to decrease surgery times and the risk of complications and increase the functional life of the implant. We focused on reducing costs, creating a feasible timeline, and ensuring compatibility with existing laboratory systems. We discuss the importance of using more biocompatible materials and enhancing osseointegration.
传统上，尽管牙科丙烯酸存在一些缺点，但一直被用于在非人灵长类动物（NHP）中植入头部固定装置和记录圆筒。在NHP研究中，使用钛和聚醚醚酮（PEEK）等生物相容性更好的材料正变得越来越普遍。我们描述了一套具有成本效益的程序，该程序在减少手术时间的同时，最大限度地提高了头柱和记录圆筒与动物组织的整合度。九只恒河猴被植入了钛制头柱，其中一只还植入了记录室。在每种情况下，都根据计算机断层扫描创建了颅骨的三维打印复制品。对头柱的钛制支脚进行了塑形，并在术前测量了颅骨厚度，手术时间最多减少了70%。记录圆筒的制造使其紧密贴合颅骨，用四颗螺丝固定在颅骨上，并在8.5个月内保持防水。我们对头柱处皮肤边缘的退缩量进行了量化。我们发现皮肤退缩的时间和程度存在很大差异，任何单一记录因素都无法解释这种差异。然而，没有一例出现骨暴露；尽管皮肤从钛上退缩，但在这些区域附近皮肤仍与颅骨粘连。在每只动物的实验期内，头柱一直功能完全正常且无并发症，其中几只动物在植入后4年多仍在参与实验。对于用非人灵长类动物进行神经生理学研究，颅骨植入物通常是必要的。我们提出了利用三维打印的猴头骨在术前制作无丙烯酸植入物的方法，以减少手术时间和并发症风险，并延长植入物的功能寿命。我们专注于降低成本、制定可行的时间表，并确保与现有实验室系统兼容。我们讨论了使用生物相容性更好的材料和增强骨整合的重要性。
