听瘤2听神经瘤的几种手术入路探讨.ppt

1、听神经瘤的几种手术入路探讨,Treatment,Operation microneurosurgery the first choiceStereotacticradiosurgery-reluctant or can not stand craniotomy-recurrence or residualGama knife,History of acoustic neuroma,Sandifort(1777)通过尸检对听神经瘤最早描述Bell（1830）生前诊断听神经瘤，并在病人死后得到证实。Balance（1894）手术成功切除，听神经瘤？脑膜瘤？Annandale（1895）Cushin

2、g采用囊内切除，提高神经切除成功率，保护面神经。Dandy（1917）成功全切。,最早的桥小脑角区听神经瘤切除术。图中清楚的勾画出了第七和第八颅神经与听神经瘤的关系。,图像来自尤曼斯第七版。,乙状窦后入路，适合于中到大型的，肿瘤主要局限在脑池内的听瘤。是大多数神经外科医生熟悉的入路。它通过暴露乙状窦的中段，即暴露横窦和乙状窦，进而暴露桥小脑角区。内听道的后段被磨开。,中颅窝入路，适合于小型肿瘤，肿瘤局限在内听道内，且听力尚存的情况下。需术中牵拉颞叶，不适合大型的听瘤。该入路的优点是能充分暴露内听道，从岩骨上段 ，暴露内听道的孔到基底部分。可能出现术后颞叶癫痫。,经迷路入路。适合于大型的听神经瘤

3、，且听力已丧失的情况。手术牺牲了迷路和听力，较好的暴露了内听道和桥小脑角，而没有明显牵拉脑质。手术暴露trautmanns三角（骨性迷路侧，乙状窦侧，天幕侧）。手术需要轻轻牵拉乙状窦。However, it offers limited access to the lower part of the CPA as well as the contents of the foramen magnum and thejugular foramen.,神经内镜辅助下的手术探索。,手术方法,切口位置：在乳突后约 1.5 cm，上端在耳 孔同枕外粗隆连线的上方取 1.5 cm，向下取约 3.04.5 c

4、m， 做皮肤纵形直线或弧形切口， 长度 4 7 cm（ 平均 5.5 cm） ；骨窗范围 3 cm3.5 cm，其上、 外部显露出横窦和乙状窦；硬膜切开后，在显微镜下 沿小脑裂中的岩裂从枕下面向岩面走行分离可到达 小脑桥脑裂尖部，轻轻牵拉小脑即可于绒球侧后方 暴露桥脑裂尖部，接着打开绒球嘴侧桥脑裂上肢的 蛛网膜，分开桥脑裂上支，打开绒球上池并释放脑脊 液可使小脑塌陷，在不牵拉小脑组织的情况下，即可 观察桥脑裂静脉，通常是汇入岩上窦的最大静脉，避 免使岩静脉承受过大张力，分开桥脑裂下支，进一步 增大手术操作空间（ 图 1）,A：岩裂分开前； B：岩裂部分分开； C：岩裂分开后； D：桥脑裂分开前

5、,E：桥脑裂部分分开； F：桥脑裂完全分开后。 注：PF小脑岩裂，CPF小脑桥 脑裂，PV岩静脉，SCA小脑上动脉，AICA小脑前下动脉，V三叉神经,A：打开小脑裂前； B：分开小脑岩裂岩静脉阻挡视野； C：分开桥脑裂，肿瘤暴露良好； D：联合小脑上入路切除肿瘤； E：全切肿瘤后岩静脉保留完好,手术操作应限于肿瘤表面蛛网膜与脑组 织表面蛛网膜之间分离，如分离中遇到较多粘连，感 觉肿瘤侵入脑组织中，可能是在肿瘤包膜与肿瘤层 蛛网膜，或脑组织固有蛛网膜层与软脑膜之间进行 分离，提示分离界面有误,解剖复习,小脑表面的形态学解剖包括三个面（ 幕面，枕下 面，岩面），8 条裂分别将蚓部和小脑半球分为 9

6、 部 脑回 。 术中常用的有岩裂（ 水平裂）， 此裂的末 端延续为小脑桥脑裂，并进一步分为两支，即上支和 下支，即是桥小脑角的界限。 桥脑裂向上移行为小 脑中脑裂， 向下移行为小脑延髓裂。,岩裂（水平裂）是小脑岩面主要脑裂，其将小脑岩面分为上下两部分，在上半月和下半月叶之间走行延伸至小脑枕下面。岩面包绕脑桥和小脑中脚形成小脑脑桥裂的上肢和下肢。小脑脑桥裂是一V 字形裂隙。岩裂和坡后裂自小脑脑桥裂尖部向上和侧方延伸。,枕下裂将小脑枕下面分为上下两部，在小脑半球分别为下半月叶和二腹小叶，小脑蚓部分别为蚓椎体和蚓结节（图 1C）。枕下裂在蚓部的经典叫法是椎体前裂，半球部分称作二腹前裂。岩裂（水平裂）

7、是小脑岩面最突出的脑裂，在上、下半月叶间延伸至小脑枕下面。,经小脑裂手术优缺点,1，手术切口小，术中显露大。充分利用了有效的骨窗，当 打开桥脑裂上支后，将小脑绒球稍向下内方牵拉，可 清楚显露面神经出脑干处，可及早辨明面神经,因打开了 桥脑裂上、 下支， 术中较容易辨认出后组颅神经、 面神经及昕神经的位置及其走行， 但如果巨大型 昕神经瘤向上方伸人四叠体池、环池、脚池和脚间 池，滑车神经和外展神经可被肿瘤推移，须小心将 这两条神经以及小脑上动脉、中脑脑桥静脉、基底 静脉与肿瘤分离,经小脑裂入路手术技术在有限的骨窗内，利用小脑自然间隙，在不牵拉或少牵拉的情况下，可以明显改变手术的暴露，扩大手术视野

8、，减少对小脑的牵拉，能够从多角度进行手术操作，减少了对岩静脉的直接操作，降低脑组织、神经、血管的牵 拉损伤风险；以较小的手术切口及骨窗范围使桥小脑角区肿瘤特别是大型肿瘤的手术效果达到或优于传统开颅手术。,经耳道-鼓岬入路,在过去十年里，内镜的引入开辟一条通往颞骨内部的新途径。特别的，耳内镜下治疗鼓室内胆脂瘤已非常成熟。由于内镜下鼓室内的解剖结构的可视性，外科医生的解剖知识也在提高，从而推动了手术指征从中耳到颅底的扩展。利用外耳道这一自然的通道到达病变，改善了目标及其周围区域的视野。内镜下经鼓室的手术，局限在内耳腔道内而没有对中颅窝或后颅窝的硬脑膜进行操作，其效果与传统的显微镜下手术有可比性。,

9、FIG. 1. Example of preoperative MRI of two patients who subsequently underwent TTEA (A) and ETA (B). Panel (C) shows an example of a CTscan performed after 5 days, with a good surgical outcome.TTEA totally transcanal endoscopic exclusive approachETA enlarged transcanal transpromontorial approach,Sch

10、ematic of the approach. a: The approach was performed transcanally without any external incision. b: Anatomy and landmarks before the operation. c: After drilling of the cochlea and removal of the ossicles. D: Visualization of the schwannoma after drilling of the IAC. e: Removal of the schwannoma. F

11、: Obliteration of the IAC by a fat pad at the end of the operation.,c 鼓索; co, cochlearopening, showing the medial and basal turns; fn, facial nerve; i, incus砧骨; m, malleus; 锤骨ow, oval window, stapes beingp, promontory骨岬; s, stapes镫骨; t, vestibular Schwannoma,Surgical steps of TTEA: exposure of the t

12、ympanic cavity (A); removal of the ossicles, leaving the stapes above the oval window (B); removal of the stapes and drilling of the promontory to expose the medial and basal turn of the cochlea (C); exposure of the schwannoma and the facial nerve (D). removed;,In ETA, after incision of the ear skin

13、, a self-retaining retractor is positioned (A). The figure shows also the tympanic cavity exposure (B), the opening of the cochlea (C), and removal of the tumor (D),co 打开的耳蜗，显露中间和基底转。fn, facial nerve;面神经 p, promontory鼓岬; r, self-retaining retractor; s, skin of the external ear外耳道皮肤; t, vestibular Sc

14、hwannoma, being removed from the IAC前庭神经鞘瘤;tc, tympanic cavity鼓室.,Results: The age of the patients (34 females and 15 males) ranged from 27 to 77 years (mean age: 54.9 yr). Preoperative diagnosis was vestibular schwannoma in all patients. At the last follow-up (range 160 mo, mean 13.9 mo), 42 of 49

15、showed grade I HB FN function, 5 of 49 grade II HB, and 2of 49 grade III HB. Overall, in 95.9%, FN function was preserved (grade III HB) with stable results at follow-up; in 4.1% of cases, FN function was reduced, but not worse than grade III.FN function was assessed according to the HouseBrackmann

16、(HB) grading system.,Audiological results were evaluated with preoperative and postoperative air conduction (AC), bone conduction (BC), airbone gaps (ABGs), and PTA, according to the AAO-HNS (9). FN function was assessed according to the HouseBrack mann (HB) grading system.也就是说面神经功能保留较好。,Preoperativ

17、e: Severe/profound hearing loss was present in 40 of 49 patients; while 9 of 49 had moderate/moderatesevere hearing loss.Postoperative: No residual hearing preservation was possible in any case because surgery used the transcochlear corridor.也就是说此手术不可能保留听力。,Other Complications,No intraoperative comp

18、lications were recorded. Postoperative complications showed four cases of cerebrospinal fluid (CSF) leakage (7.4%), 1 after TTEA and 3 after ETA. Two required revision surgery with fat repositioning and suture after 10 days and 4 months, one was treated only with the placement of lumbar drainage, an

19、d one was maintained in observation recovery until spontaneous resolution. 脑脊液漏Three cases of dehiscence of the suture of the EAC were also noted, requiring a postoperative office-based suture.外耳道缝线裂开 No trigeminal, abducens, or lower cranial nerve damage was observed. Finally, there were no cases o

20、f hydrocephalus or acute bleeding (due todamage to vascular structures), and no cases of meningitis (0%) were observed.无三叉神经、展神经、后组颅神经损伤；无脑积水、无脑出血,其他资料图片解读：,iac =internal auditory canal 内听道,小结,1，常规的乙状窦后入路2，中颅窝入路3，经迷路入路4，经小脑裂入路，解剖复习5，内镜下经耳道鼓岬入路，TTEA和ETA,预告,听神经瘤诊治在神经影像和电生理方面的进展。二型神经纤维瘤病的几个难点分析。,Thanks for your attention！,