Trautmann's triangle anatomy with application to posterior transpetrosal and other related skull base procedures

Trautmann's triangle (TT) faces the cerebellopontine angle and is exposed during posterior transpetrosal approaches. However, reports on the morphometric analysis of this structure are lacking in the literature. The goal was to better understand this important operative corridor. TT was exposed from an external approach (transmastoid) in ten cadavers (20 sides) and from an internal approach on 20 dry adult temporal bones. Measurements included calculation of the area of TT and the distance of the endolymphatic sac from the anterior border of the sigmoid sinus. The area range of TT was 45–210 mm² (mean 151 mm²; SD 37 mm²). Three types of triangles were identified based on area. Type I triangles had areas less than 75 mm², Type II areas were 75–149 mm², and Type III areas were 150 mm² and greater. These types were observed in 37.5%, 35%, and 27.5% of sides, respectively. The distance from the jugular bulb's anterior border to the posterior border of the posterior semicircular canal ranged from 6 to 11 mm (mean 8.5 mm). The endolymphatic sac was located in the inferior portion of TT and traveled anterior to the sigmoid sinus. The horizontal distance from the anterior edge of the sigmoid sinus to the posterior edge of the endolymphatic sac ranged from 0 to 13.5 mm (mean 9 mm). Additional anatomic knowledge regarding TT may improve neurosurgical procedures in this region by avoiding intrusion into the endolymphatic sac and sigmoid sinus. Clin. Anat. 27:994–998, 2014. © 2014 Wiley Periodicals, Inc.     

颅底段展神经的应用解剖

目的 :为颅底外科提供展神经的显微解剖学资料。方法 :观测 15例 ( 3 0侧 )成人头颅湿标本展神经的位置、行径及重要毗邻关系。结果 :①展神经在硬脑膜入口处两侧间距 ( 19.71± 1.79)mm ;②Dorello管顶与底间最大垂直距离 ( 2 .14± 0 .70 )mm ;③展神经在海绵窦内距破裂孔硬膜环 ( 5 .69± 1.45 )mm。结论 :在颞骨岩部、海绵窦及眶上裂区手术 ,展神经必须予以辨认和保护     

侧颅底手术中乙状窦应用解剖学研究

目的　探讨侧颅底手术中乙状窦相关解剖标志的位置，为进一步提高侧颅底手术安全性提供解剖学基础。 方法　选取成人头颅标本40个，采用耳后切口行标准乳突根治术。充分暴露颅中窝及颅后窝硬脑膜、外半规管、面神经膝部、乙状窦、颈静脉球、乳突、茎乳孔、二腹肌嵴、外耳道后壁等重要解剖结构。使用双脚规测径器或电子数显游标卡尺分别测量相关解剖结构之间的距离。 结果　乙状窦前缘至外耳道后壁的距离是(1.41±0.32)cm，乙状窦外侧壁至乳突外侧壁的距离是(1.02±0.38)cm，面神经乳突段的长度是(1.28±0.13)cm，面神经乳突段起点（即面神经膝部）到乙状窦的距离是(0.56±0.20)cm，面神经乳突段终点（即茎乳孔部）到乙状窦的距离是(0.62±0.22)cm，二腹肌嵴至乙状窦的距离是(0.52±0.18)　cm，茎乳孔至乙状窦的距离是(1.02±0.24)cm。 结论　面神经乳突段起点和终点至乙状窦的距离及乙状窦至二腹肌嵴和茎乳孔之间的距离均呈正相关；乙状沟的深浅、宽窄及骨壁的厚薄因乳突气化程度不同而各异。     

颞下经下颌入路显露侧颅底区的应用解剖学研究

目的研究颞下经下颌入路应用解剖,为术中保护重要结构提供解剖学参考。方法选用成人尸头10例(20侧),摹拟手术入路,解剖观察、测量相关结构,探求入路涉及的骨、肌肉和神经血管间的解剖关系。结果影响该入路暴露的主要结构包括面神经、腮腺、颧弓和下颌升支。颞下窝和翼腭窝血管神经丰富,茎突及其筋膜将咽旁间隙分为咽旁前和咽旁后间隙,后者容纳颈内静脉、颈内动脉和Ⅸ、Ⅹ、Ⅺ及Ⅻ对脑神经。结论颞下经下颌入路暴露充分,熟悉其应用解剖对手术治疗侧颅底区沟通性肿瘤具有重要意义。     

钛网片在前颅底手术颅底重建中的美容作用

目的 探讨钛网片和带蒂颅骨膜在伴有较大颅底缺损的前颅底手术颅底重建术中的美容作用。方法 将钛网片放在折叠的具有良好血供的带蒂颅骨膜两层之间，对23例具有较大颅底缺损的患者进行颅底重建。结果 23例手术后无感染出现，无脑膜脑膨出，及局部塌陷，颅眶畸形得以矫正，容貌恢复满意，6例术后出现短时间脑脊液鼻漏，经腰穿和静脉预防性应用抗生素痊愈。结论 应用钛网片和血供良好的带蒂颅骨膜重建前颅底有很好的美容作用。     

颅底外面部分骨性标志三维坐标值及其意义

目的 :探讨测量颅底外面解剖结构三维空间坐标的方法并为临床应用提供相关数据。方法 :建立与颅底内面相统一的三维空间坐标系 ,在特制颅器上以 3 2个成年国人水平锯开颅骨标本为测量对象。结果 :测出了颅底外面骨性标志 2 1项共 3 4个测点的三维空间坐标值 ;可准确地测算出各测点在颅表各个方位的投影点和深度 ;根据坐标值和解析几何公式 ,还可推算出所有测点间连线 (线段 )的距离 (测距 )及其与三个基准坐标面的角度 (测角 )。结论 :明确了颅底外面各测点的空间位置和颅底内外两面任何测点间的位置关系 ,为颅底手术定位或放疗照射野等定位设计 ,提供了更为简便可靠的新方法。     

内窥镜下与颅底相关的鼻腔鼻窦解剖标志的研究

目的：研究内窥镜下鼻颅底相关的解剖标志及其在手术中的意义。方法：观测4例尸体标本和术时179个病例与颅底相关的鼻腔鼻窦解削结构。结果：(1)筛前动脉位于额隐窝后隆突或其后2～3mm范围;筛前动脉骨管可呈管状或管状悬空占58．2％,呈嵴状或半管状占41．8％。(2)纸样板与筛顶的连接方式有直角为3％,钝角44％,锐角53％．(3)蝶窦前壁位于后鼻孔上缘上,鼻中隔和中鼻甲后缘之间。(4)蝶窦外侧壁视神经管隆起呈管型或半管型为15．4％,压迹型35.3％。颈内动脉隆起60％。(5)蝶骨嵴延长线为鞍底中线。结论：(1)作为判断筛顶或蝶窦侧壁重要标志的额隐窝、筛前动脉或视神经管隆起、颈内动脉隆起是有一定的解剖变异．(2)中鼻甲前后附着缘、上颌窦口、后鼻孔上缘和纸样板是可供参照的相对恒定标志。(3)蝶骨嵴可作为判断鞍底中线的标志。     

基于薄层标本断面建立可视性三维颅底模型*

目的：为了帮助临床医生学习颅底解剖,创建一个颅底三维模型。方法：应用冷冻铣切技术,获得横断和 冠状薄层断面照片,对于系列照片进行分割、标志、提取颅底结构信号,然后通过Amira 3D 软件,重建了1 个颅 底三维模型。结果：共获得了780 张冠状断面和430 张横断面图片,在这些断面上,颅底的一些精细解剖结构可 以被追踪。成功重建的颅底3D模型可以在任何模式旋转和缩放。但是,因为该模型是在2 个头部标本的基础上 建立的,颅底解剖的变异不能被该模型显示。结论：重建的3D模型可以准确展示颅底解剖结构,它有利于外科 解剖培训,可用来完成术前的手术模拟。     

An orthotopic skull base model of malignant meningioma

Meningioma tumor growth involves the subarachnoid space that contains the cerebrospinal fluid. Modeling tumor growth in this microenvironment has been associated with widespread leptomeningeal dissemination, which is uncharacteristic of human meningiomas. Consequently, survival times and tumor properties are varied, limiting their utility in testing experimental therapies. We report the development and characterization of a reproducible orthotopic skull-base meningioma model in athymic mice using the IOMM-Lee cell line. Localized tumor growth was obtained by using optimal cell densities and matrigel as the implantation medium. Survival times were within a narrow range of 17-21 days. The xenografts grew locally compressing surrounding brain tissue. These tumors had histopathologic characteristics of anaplastic meningiomas including high cellularity, nuclear pleomorphism, cellular pattern loss, necrosis and conspicuous mitosis. Similar to human meningiomas, considerable invasion of the dura and skull and some invasion of adjacent brain along perivascular tracts were observed. The pattern of hypoxia was also similar to human malignant meningiomas. We use bioluminescent imaging to non-invasively monitor the growth of the xenografts and determine the survival benefit from temozolomide treatment. Thus, we describe a malignant meningioma model system that will be useful for investigating the biology of meningiomas and for preclinical assessment of therapeutic agents.     

Transnasal endoscopic skull base surgery in the COVID-19 era: Recommendations for increasing the safety of the method

Transnasal endoscopic skull base surgery (eSBS) has been adopted in recent years, in great part to replace the extended procedures required by external approaches. Though sometimes perceived as “minimally invasive”, eSBS still necessitates extensive manipulations within the nose/paranasal sinuses. Furthermore, exposure of susceptible cerebral structures to light and heat emanated by the telescope should be considered to comprehensively evaluate the safety of the method. While the number of studies specifically targeting eSBS safety still remains scarce, the problem has recently expanded with the SARS-CoV-2 pandemic, which also has implications for the safety of the surgical personnel.It must be stressed that eSBS may directly expose the surgeon to potentially high volumes of virus-contaminated aerosol. Thus, the anxiety of both the patient and the surgeon must be taken into account. Consequently, safety requirements must follow the highest standards. This paper summarizes current knowledge on SARS-CoV-2 biology and the peculiarities of human immunology in respect of the host-virus relationship, taking into account the latest information concerning the SARS-CoV-2 worrisome affinity for the nervous system. Based on this information, a workflow proposal is offered for consideration. This could be useful not only for the duration of the pandemic, but also during the unpredictable timeline involving our coexistence with the virus. Recommendations include technical modifications to the operating theatre, personal protective equipment, standards of testing for SARS-CoV-2 infection, prophylactic pretreatment with interferon, anti-IL6 treatment and, last but not least, psychological support for the patient.     

面部组织移位入颅底手术的临床解剖学研究

目的：为面部移位颅底手术入路提供解剖学基础。方法：在３６侧成人头面部标本上，对面神经、腮腺管的位置和层次进行了观察与定位。结果：①面动脉在眶下缘水平至鼻旁间距为９．９±５．０ｍｍ，至骨膜的深距为２．１±０．８ｍｍ；②面神经由茎乳孔出颅后，经腮腺、咬肌和颊区三段分布于面肌。在咬肌段，面神经紧贴咬肌表面行走，面神经颧支行于颧骨表面，至骨面的最小深距为１ｍｍ。结论：①旁正中切口不会影响面动脉；②掀翻面肌皮瓣时，颧骨表面和咬肌表面的面神经分支是易损伤区     

颞下窝的CT影像与断层标本对照研究及临床意义

目的:为颞下窝病变的影像诊断及手术入路提供解剖学资料.方法:选取志愿者40名,在螺旋CT机上以眦耳线(CML)为基线对颞下窝结构进行层厚1mm连续扫描.选取成人尸体头颈部标本20例,以CML为基线制成层厚5mm连续断层标本.在经冠突和茎突末端层面的CT影像及断层标本上,观察颞下窝及其邻近结构的解剖学关系,测量其长径、宽径和面积.结果:颞下窝的形态呈不规则状,在CT影像和断层标本上经冠突、茎突末端层面的面积分别为(1055.6 +2.05)mm2和(1034.5±3.32) mm2、(356.6±1.78) rm2和(345.8±1.89) mm2.两侧颞下窝及其结构呈对称性,长径、横径和面积侧别间比较差异均无统计学意义(P＞0.05).自茎突至翼突外侧板前缘或翼突内侧板后缘的连线可区分颞下窝与咽旁间隙,茎突、冠突、翼外肌、翼突外侧板和翼突内侧板是CT影像诊断的重要解剖学标志.结论:颞下窝的CT影像与断层标本的解剖对照研究,对颞下窝肿瘤等疾病的影像诊断及指导手术入路具有重要临床意义.     

Carcinoma of temporal bone, base of the skull: diagnosis by needle aspiration cytology

We report on a 68-yr-old male with a destructive bone lesion involving the temporal bone at the skull base extending to surrounding osseous structures and the infratemporal fossa, defined by needle aspiration cytology as carcinoma in association with inflammatory reaction, bacterial type, and bone destruction. The technique of the aspiration, which was performed by a cytopathologist directing a spinal needle into the region of the destroyed temporal bone as outlined in the radiographs of prior magnetic resonance imaging (MRI), is discussed. The application of this technique in the cytologic sampling of deeper lesions usually of soft or osseous tissues not accessible to ordinary fine-needle aspiration is presented. There is also a brief discussion of neoplastic lesions involving the temporal bone at the skull base and the anatomic concerns in sampling lesions in this difficult-to-approach region of the body.     

颞肌瓣鼻颅底区转位的解剖

目的 探讨颞肌瓣的显微和内镜解剖，为使用颞肌瓣（TMF）进行内镜下颅底重建提供解剖学资料。方法 在6例共12侧新鲜灌注的头颅标本上进行颞肌瓣的解剖，测量颞肌瓣的长度和宽度，显露颞肌瓣的血供；将获取的颞肌瓣经颞下窝、上颌窦路径转位至鼻颅底区进行颅底重建，分析其所能覆盖的颅底区域。结果 获取的颞肌瓣平均长度为（11.7±0.7）cm，宽度为（9.2±0.8）cm。颞肌瓣经颞下窝、上颌窦路径可有效地转位至鼻颅底区，覆盖前颅底、鞍区和斜坡区。结论 将颞肌瓣经颞下窝、上颌窦径路转位至鼻颅底区进行有效的颅底重建，在内镜颅底手术后的颅底重建方面具有较好的应用前景。     

侧颅底冠状位组织学与CT断层的对照

目的 制作颞骨火棉胶冠状位断层连续薄层切片,获取数字化图片库。方法 用2例尸头标本进行螺旋CT扫描后制作断层标本火棉胶包埋后,用大型轮式切片机沿冠状位切片,厚度100μm,每片均摄影并保存于计算机。选取代表性层面的胶片进行HE染色。将断层照片与HE染色照
片和CT片进行对照观察,对代表性层面结构特点进行描述。结果 共获取侧颅底数字化连续冠状位薄层断面标本数据集 2套。断层图像分辨率1920×2560像素,结构毗邻关系显示清晰。与HE照片和CT片进行对照观察,可以更清楚地定位断层结构。结论 火棉胶包埋技术是制作颞骨大切
片,获取高分辨率的数字化图片数据集的理想方法。冠状位对听小骨、Prussak‘s间隙、颈静脉窝、耳蜗与中颅窝的关系,颈内动脉升段及膝部、面神经垂直段、内听道与中颅窝的关系等显示较佳。     

侧颅底神经血管的应用解剖学——颞下窝径路的外科解剖学研究

目的：通过对侧颅底区神经血管的临床应用解剖学观察,为术中保全脑神经和重要血管提供解剖学基础。方法：对２１侧成人尸头按ＦｉｓｃｈＡ、Ｂ型颞下窝手术进路进行解剖,观察颈静脉球区域神经血管解剖关系;观察颈内动脉及毗邻的解剖关系。结果：颈静脉球可分为隆起型（占６６．７％）和低平型（占３３．３％）。岩下窦开口部位有三种类型。Ⅸ脑神经多位于颈静脉球的前内侧,Ⅹ、Ⅺ脑神经多位于其内侧。Ⅺ脑神经与岩下窦末端关系密切,可分三种类型。颈内动脉水平段距鼓膜张肌平均为２．２ｍｍ,距脑膜中动脉和下颌神经分别平均为６．８ｍｍ和６．９ｍｍ。结论：避免手术损伤后脑神经的关键是充分暴露,辨认清楚后明视下操作。鼓膜张肌、脑膜中动脉、下颌神经是预测和辨认颈内动脉水平的良好标志。     

Plagiocephaly: morphometry of skull base asymmetry

The aim of this study was to perform a morphometric analysis of the skull base to understand the mechanism of asymmetry between malformational and deformational plagiocephaly. Since 1988, we have carried out 102 CT scans with three-dimensional reconstruction of the endocranial side of the skull base. There were 20 cases of malformational plagiocephaly, consisting of 18 unicoronal synostoses (UCS) and two unilambdoid synostoses (ULS), and 82 cases of plagiocephaly without synostosis, made up of 60 cases of frontal plagiocephaly (FP) and 22 of occipital plagiocephaly (OP). The skull base asymmetry was analyzed in three ways: (1) the hemibases and the cranial fossa angles were compared with each other; (2) the structural asymmetry of the chondrocranium was calculated; and (3) the architectural asymmetry was measured in relation to the medio-labyrinthine plane. The skull base asymmetry of malformational plagiocephaly was located in the anterior and middle cranial fossae for UCS and in the posterior and middle cranial fossae for ULS. The asymmetry was the result of a localized structural anomaly of the chondrocranium. The asymmetry of deformational plagiocephaly corresponded to a distortion in relation to the medio-labyrinthine plane while the chondrocranium remained symmetric. The skull base asymmetry of malformational plagiocephaly is secondary to a localized malformation of the chondrocranium, and that of the deformational plagiocephaly is secondary to an architectural deformation.

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Electronic Supplementary Material The french version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer Link server located at .

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Les plagiocéphalies: morphométrie de l'asymétrie de la base du crâne

Résumé Le but de cette étude était de réaliser une analyse morphométrique de la base du crâne pour comprendre les mécanismes de l'asymétrie entre les plagiocéphalies malformatives et déformatives. Depuis 1988, 102 reconstructions 3D de la surface endocrânienne de la base et al. âne ont été réalisées. Il s'agissait de 20 plagiocéphalies malformatives, 18 synostoses unicoronales (SUC) et 2 synostoses unilambdoïdes (SUL), et de 82 plagiocéphalies sans synostose, 60 plagiocéphalies frontales (PF) et 22 occipitales (PO). L'asymétrie de la base du crâne était analysée de trois manières: (1) les hémi-bases et les fosses crâniennes étaient comparées les unes aux autres, (2) l'asymétrie structurale du chondrocrâne était calculée, et (3) l'asymétrie architecturale était mesurée par rapport au plan médio-labyrinthique. L'asymétrie de la base du crâne des plagiocéphalies synostotiques était localisée aux fosses crâniennes antérieure et moyenne pour les SUC et aux fosses crâniennes postérieure et moyenne pour les SUL. L'asymétrie était secondaire à une anomalie de structure localisée du chondrocrâne. L'asymétrie des plagiocéphalies sans synostose correspondait à une distorsion autour du plan médio-labyrinthique alors que le chondrocrâne restait symétrique. L'asymétrie de la base du crâne des plagiocéphalies malformatives est secondaire à une malformation localisée du chondrocrâne, et celle des plagiocéphalies déformatives est secondaire à une déformation architecturale.

     

Bony eminence on the middle cranial fossa corresponding to the temporomandibular joint

We report a nameless bony eminence over the temporomandibular joint (TMJ) and its possible clinical significance. Forty-two half heads of 21 UK Caucasian cadavers (61-95 years old, mean 84.3 +/- 8.2 years, male:female = 11:10) were used to investigate the surface of the middle cranial fossa (MCF) over the TMJ. The thickness of the bony roof of the glenoid fossa was also measured. A bony eminence over the glenoid fossa was observed in half of the specimens. Some showed a complete oval bulge, which completely reflected the contour of the glenoid fossa. The others showed a bony bulge, which partially reflected that contour. The mean (+/-SD) thickness of the bone in the roof of glenoid fossa was 1.5 +/- 1.2 mm. The mean bony thickness of specimens showing the eminence was 0.8 +/- 0.5 mm, whereas it was 2.3 +/- 1.2 mm in specimens without an eminence. These differences were statistically significant (P < 0.01). The osteological features we describe may be relevant to certain clinical problems. Traumatic dislocation of mandibular condyle, for example, might relate to a weakness of the glenoid fossa.