Adunka Oliver F, Pillsbury Harold C, Kiefer Jan
Department of Otolaryngology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
Acta Otolaryngol. 2006 May;126(5):475-82. doi: 10.1080/00016480500437393.
Except for basal cochlear traumatization, all specimens implanted into scala tympani showed atraumatic insertion properties and good perimodiolar electrode positioning. Cochleostomy preparation and placement can have a significant impact on levels of basal cochlear trauma.
In the past, perimodiolar cochlear implant electrodes increased the risk for intracochlear traumatization when compared to free-fitting arrays. Recently, however, clinical evidence for atraumatic perimodiolar implantations with preservation of residual hearing has been described. The aim of this paper was to histologically evaluate a perimodiolar cochlear implant array for its insertion properties in cadaver human temporal bones. Surgical and electrode factors, as well as preparation artifacts influencing intracochlear trauma, were considered in the evaluation.
Sixteen human temporal bones were harvested up to 24 hours post mortem and implanted immediately with the Nucleus 24 Contour Advance cochlear implant electrode array. Implantations were either performed using a regular caudal approach cochleostomy or through the round window membrane. After implantation, all bones underwent special histological processing, which allowed sectioning of undecalcified bone. Insertion properties were evaluated according to a grading system.
Fourteen specimens were implanted into scala tympani and only two exhibited basal trauma attributable to electrode insertion characteristics. Two bones were implanted into scala vestibuli after causing trauma in the region of the cochleostomy. Insertion depths ranged from 180 degrees to 400 degrees. All bones showed good perimodiolar electrode positioning. Basal trauma due to surgical issues and histological artifacts was present in 10 of 16 bones.
除了基底耳蜗创伤外，所有植入鼓阶的标本均显示出无创插入特性及良好的蜗轴周围电极定位。蜗窗造口术的准备和放置对基底耳蜗创伤程度可能有重大影响。
过去，与自由放置的阵列相比，蜗轴周围人工耳蜗电极增加了耳蜗内创伤的风险。然而，最近已有关于保留残余听力的无创蜗轴周围植入术的临床证据报道。本文旨在通过组织学评估蜗轴周围人工耳蜗阵列在尸体颞骨中的插入特性。评估时考虑了手术和电极因素，以及影响耳蜗内创伤的准备过程中的假象。
在死后24小时内采集16块人类颞骨，并立即植入Nucleus 24 Contour Advance人工耳蜗电极阵列。植入采用常规的尾侧入路蜗窗造口术或通过圆窗膜进行。植入后，所有颞骨均经过特殊的组织学处理，以便对未脱钙的骨进行切片。根据分级系统评估插入特性。
14个标本植入鼓阶，只有2个因电极插入特性而出现基底创伤。2块颞骨在蜗窗造口区域造成创伤后植入前庭阶。插入深度范围为180度至400度。所有颞骨均显示出良好的蜗轴周围电极定位。16块颞骨中有10块因手术问题和组织学假象出现基底创伤。
