Gerek Mustafa, Satar Bülent, Yazar Fatih, Ozan Hasan, Ozkaptan Yalçin
Department of Otolaryngology--Head and Neck Surgery, Gülhane Askeri Tpi Akademisi, Ankara, Turkey.
Otol Neurotol. 2004 Nov;25(6):973-6. doi: 10.1097/00129492-200411000-00018.
To investigate the utility of a newly described approach, the transcanal anterior approach that is a modification of the subcochlear approach for the drainage of cystic lesions of the petrous apex.
Prospective temporal bone study.
Tertiary referral center.
A total of six cadaveric temporal bone specimens (four males) were included. Right ear in four specimens and left ear in two specimens were used.
The approach commenced with postauricular skin incision. After the transsection of the meatal skin, antero-inferior tympanotomy was performed. Anteroinferior canaloplasty localized the carotid canal. As much as 0.5 cm of the vertical segment of the internal carotid artery was skeletonized. After the identification of the artery, petrous apex cells were reached by drilling the cortical bone between the cochlea and the internal carotid artery. An air cell tract was established. Position and length of the tract in two specimens were demonstrated on the 1 mm-cut computerized tomography scans.
Utility of the approach was investigated based on the established criteria: anteroposterior diameter and height of the fenestra of the tract, length of the tract from the cochlea to the deepest point of the tract (depth of the tract), and the injury risk of the internal carotid artery and the cochlea.
The mean anteroposterior diameter, the height, and the length were 4.7 +/- 1.05 mm, 3.2 +/- 0.68 mm, and 14.7 +/- 1.1 mm, respectively. Injury did not occur in the cochlea or internal carotid artery in any of the specimens.
With the subcochlear approach, there is always potential risk of injury to the cochlea, the internal carotid artery, and the jugular bulb. Although this new approach includes a technically challenging stage (exposing the vertical portion of the internal carotid artery), partly exposing the vertical portion of the artery provides a safer approach, which decreases the injury risk for the round window and the jugular bulb. Additionally, measurements show that it is possible to reach a considerable part of the petrous apex cells.
探讨一种新描述的入路——经耳道前路入路（该入路是对耳蜗下入路的改良，用于引流岩尖囊性病变）的实用性。
颞骨前瞻性研究。
三级转诊中心。
共纳入6个尸体颞骨标本（4例男性）。其中4个标本用于右侧耳朵，2个标本用于左侧耳朵。
该入路始于耳后皮肤切口。横断耳道皮肤后，进行前下鼓室切开术。前下鼓室成形术确定颈动脉管位置。将颈内动脉垂直段多达0.5 cm的部分进行骨骼化处理。识别出动脉后，通过钻开耳蜗与颈内动脉之间的皮质骨到达岩尖气房。建立一个气房通道。在1毫米层厚的计算机断层扫描上显示了两个标本中通道的位置和长度。
根据既定标准研究该入路的实用性：通道开窗的前后径和高度、通道从耳蜗到最深点的长度（通道深度）以及颈内动脉和耳蜗的损伤风险。
平均前后径、高度和长度分别为4.7±1.05毫米、3.2±0.68毫米和14.7±1.1毫米。所有标本中耳蜗或颈内动脉均未发生损伤。
采用耳蜗下入路时，耳蜗、颈内动脉和颈静脉球始终存在潜在损伤风险。尽管这种新入路包括一个技术上具有挑战性的阶段（暴露颈内动脉垂直段），但部分暴露动脉垂直段提供了一种更安全的入路，降低了圆窗和颈静脉球的损伤风险。此外，测量结果表明，可以到达相当一部分岩尖气房。
