Varadarajan Varun V, Dayton Orrin L, De Jesus Reordan O, Sarntinoranont Malisa, Antonelli Patrick J
Department of Otolaryngology, University of Florida, Gainesville, FL, USA.
Department of Radiology, University of Florida, Gainesville, FL, USA.
Int J Pediatr Otorhinolaryngol. 2019 Nov;126:109601. doi: 10.1016/j.ijporl.2019.109601. Epub 2019 Jul 26.
Perilymph gusher (PLG), an uncommon complication of otologic surgery, has been attributed to communication between the cochlea and the internal auditory canal (IAC). Subtle osseous defects may be missed on routine review of computed tomography (CT). This study aimed to quantify cochlear basal turn patency not seen on axial CT in patients with PLG and compare those against patients without intraoperative PLG.
Ears that underwent cochlear implantation or stapedotomy with preoperative helical CT that was interpreted as "normal" at a tertiary referral center. An otologist and a radiologist independently and in a blinded fashion measured the dimensions of cochlear basal turn patency on CT images in oblique plane and parasagittal planes along the interface of the cochlea and IAC fundus.
Sixty-one ears were reviewed, including 3 with surgically confirmed PLGs and 12 with apparent dehiscence without a PLG. Mean defect width with PLG was 0.83 mm (range 0.75-0.9 mm) and without PLG was 0.43 mm (range 0.3-0.65 mm, p = 0.011). A greater proportion of PLGs occurred in ears with defects (3 of 15) than in ears without (0 of 46, p = 0.013). Using a cutoff of 0.75 mm, a greater proportion of PLGs occurred with defect width >0.75 mm (3 of 3) than in defects <0.75 mm (0 of 12, p = 0.022).
CT dehiscence between the IAC and cochlear basal turn, particularly with a width > 0.75 mm, should be considered a risk for PLG with stapedotomy or cochlear implantation.
外淋巴瘘（PLG）是耳科手术中一种罕见的并发症，其原因被认为是耳蜗与内耳道（IAC）之间存在连通。在计算机断层扫描（CT）的常规检查中，可能会遗漏细微的骨质缺损。本研究旨在量化PLG患者轴向CT上未显示的耳蜗底转通畅情况，并将其与术中未发生PLG的患者进行比较。
在一家三级转诊中心，对接受了耳蜗植入或镫骨手术且术前螺旋CT被解读为“正常”的耳朵进行研究。一名耳科医生和一名放射科医生以独立且盲法的方式，在沿着耳蜗与IAC底部界面的斜平面和矢状旁平面的CT图像上测量耳蜗底转通畅的尺寸。
共评估了61只耳朵，其中3只经手术证实有PLG，12只虽有明显裂隙但无PLG。有PLG的平均缺损宽度为0.83毫米（范围0.75 - 0.9毫米），无PLG的为0.43毫米（范围0.3 - 0.65毫米，p = 0.011）。有缺损的耳朵中发生PLG的比例（15只中有3只）高于无缺损的耳朵（46只中有0只，p = 0.013）。以0.75毫米为临界值，缺损宽度>0.75毫米时发生PLG的比例（3只中有3只）高于缺损宽度<0.75毫米时（12只中有0只，p = 0.022）。
IAC与耳蜗底转之间的CT裂隙，尤其是宽度>0.75毫米时，应被视为镫骨手术或耳蜗植入发生PLG的风险因素。
