鼻内镜下鼻后神经丛解剖研究

目的 探讨鼻内镜下鼻后神经丛(PNNP)的构成及分布特点,为后续行鼻内镜下高选择性PNNP切断术提供解剖学参考。方法 利用5具(10侧)冰鲜尸头灌注标本,经内镜下中鼻道入路,解剖蝶腭孔周围区域内结构;利用5具人体标本解剖前接受的鼻窦CT扫描结果,经影像学工具测量相应结构间距离。利用内镜系统采集解剖图像,影像测量软件获取影像学数据,并由资深放射科医师盲法测量。在解剖过程中,寻找蝶腭孔周围区域重要解剖标志及各结构间的毗邻关系。去除腭骨蝶突及蝶骨鞘突骨质,开放骨性腭鞘管,暴露PNNP咽支,在腭鞘管前口外侧探查定位翼管神经。结果 PNNP出蝶腭孔后均存在3个主要分支与蝶腭动脉分支血管伴行,前下方有与蝶腭鼻后外侧支伴行的鼻腔外侧壁支,后上方有与上鼻甲动脉伴行的上鼻甲支,后内侧有与鼻后中隔动脉伴行的鼻中隔支,蝶腭神经节在翼腭窝内即发出咽支,未穿出蝶腭孔,通过腭鞘管进入鼻咽部,且翼管前口均位于腭鞘管前口的外侧。腭鞘管前口外侧壁至翼管前口内侧壁间距,内镜下测量值(5.90±1.12)mm,影像学测量值(6.30±1.06)mm。结论 通过解剖定位腭鞘管,开放骨性腭鞘管,暴露其中的PNNP咽支,探讨腭鞘管前口与翼管前口之间的位置关系及术中规避翼管神经及蝶腭神经节的安全操作范围,为变应性鼻炎精准手术治疗提供解剖依据。     

Endoscopic anatomy of the pterygopalatine fossa

BACKGROUND: The pterygopalatine fossa can be involved with a variety of infectious and neoplastic processes. This region can be entered endoscopically, but endoscopic landmarks to localize the neurovascular structures in the pterygopalatine fossa have not yet been reported. OBJECTIVES: The purpose of this study is to describe the location of the neurovascular structures in the pterygopalatine fossa in relation to consistent intranasal landmarks. METHODS: Endoscopic dissections of cadaveric heads were performed. The locations of neurovascular structures in the region were defined. RESULTS: The sphenopalatine foramen (SPF) served as the primary intranasal landmark to the pterygopalatine fossa (PPF). Mean distances from the SPF were measured with the following results: SPF to sphenopalatine ganglion (SPG), 4 mm medially and 6 mm laterally; SPF to foramen rotundum (FR), 7 mm; and SPF to vidian canal (VC), 2 mm. The internal maxillary artery followed an irregular and inconsistent course, making it difficult to define a reliable landmark for its location in the fossa. CONCLUSION: Entering the PPF inferior to the horizontal plane of the SPF along a vertical line drawn inferiorly from the infraorbital canal will avoid injury to the major neural structures in the fossa. Because of the inconsistent course and location of the internal maxillary artery, this structure may be at risk no matter where the fossa is entered. These landmarks will allow the surgeon to enter the PPF with more accuracy and less patient morbidity.     

鼻内镜下颌内动脉翼腭段应用解剖及其意义

目的通过鼻内镜经鼻腔入路对颌内动脉翼腭段及其周围区域的解剖学研究,为临床鼻内镜下颌内动脉翼腭段区域手术提供解剖学基础。方法对10具(20侧)新鲜尸头经鼻内镜下鼻腔外侧壁入路对侧颅底翼腭窝区域进行解剖学观测,正中矢状锯开标本观测内镜下解剖标志及颌内动脉翼腭段分支变异及邻近血管神经结构。结果①颌内动脉翼腭窝段变异较大,颌内动脉翼腭段按顺序发出分支占25%(5/20),眶下动脉和上牙槽后动脉共干发出占50%(10/20),分别由颌内动脉发出占40%(8/20);颌内动脉同时发出眶下动脉、腭降动脉、蝶腭动脉占10%(2/20);眶下动脉和腭降动脉共干发出占10%(2/20);翼管动脉和圆孔动脉分别由颌内动脉发出及共干发出各占50%(10/20);②鼻内镜下能够较好的控制颌内动脉及其分支,对周围结构触动少。结论掌握颌内动脉翼腭段及其周围区域的解剖可降低鼻内镜下该区域手术的并发症,对于翼腭窝手术及治疗顽固性鼻出血有重要意义。     

Surgical anatomy of the sphenopalatine artery in lateral nasal wall

OBJECTIVE: We investigated the surgical anatomy of the sphenopalatine artery. First, the location of the sphenopalatine foramen on the lateral nasal wall and the pattern of the main branches of the sphenopalatine artery from the sphenopalatine artery were studied. Second, the course of the posterior lateral nasal artery with respect to the posterior wall of the maxillary sinus, the perpendicular plate of the palatine bone, and the pattern of distribution of its branches on the fontanelle was determined. Third, the distribution pattern on the inferior turbinate was analyzed. STUDY DESIGN: Fifty midsagittal sections of randomly selected Korean adult cadaver heads with intact sphenoid sinus and surrounding structures were used in the study. METHODS: The mucosa on the sphenopalatine foramen and its surrounding mucosa were removed with a microscissors, a fine forceps, and a pick to expose the sphenopalatine artery under an operating microscope (original magnification x6). RESULTS: The feeding vessels of the superior turbinate were from the septal artery in 36 cases (72%). The feeding vessels to the middle turbinate branch originated from the proximal portion of the posterior lateral nasal artery just after exiting the sphenopalatine foramen in 44 cases (88%). Some portion of the posterior lateral nasal artery ran anterior to the posterior wall of the maxillary sinus in 38%. The major feeding arteries to the fontanelle were from the inferior turbinate branch in 25 cases (50%). In most cases, the inferior turbinate branch was the end artery of the posterior lateral nasal artery (98%). CONCLUSIONS: The study provides detailed information concerning the sphenopalatine artery, which we hope will help explain the arterial bleeding that may occur during ethmoidectomy, middle meatal antrostomy, conchotomy, and endoscopic ligation of the sphenopalatine artery.     

Endoscopic anatomy of the pterygopalatine fossa and the transpterygoid approach: development of a surgical instruction model

INTRODUCTION: The pterygopalatine fossa (PPF) is a narrow space located between the posterior wall of the antrum and the pterygoid plates. Surgical access to the PPF is difficult because of its protected position and its complex neurovascular anatomy. Endonasal approaches using rod lens endoscopes, however, provide better visualization of this area and are associated with less morbidity than external approaches. Our aim was to develop a simple anatomical model using cadaveric specimens injected with intravascular colored silicone to demonstrate the endoscopic anatomy of the PPF. This model could be used for surgical instruction of the transpterygoid approach. METHODS: We dissected six PPF in three cadaveric specimens prepared with intravascular injection of colored material using two different injection techniques. An endoscopic endonasal approach, including a wide nasoantral window and removal of the posterior antrum wall, provided access to the PPF. RESULTS: We produced our best anatomical model injecting colored silicone via the common carotid artery. We found that, using an endoscopic approach, a retrograde dissection of the sphenopalatine artery helped to identify the internal maxillary artery (IMA) and its branches. Neural structures were identified deeper to the vascular elements. Notable anatomical landmarks for the endoscopic surgeon are the vidian nerve and its canal that leads to the petrous portion of the internal carotid artery (ICA), and the foramen rotundum, and V2 that leads to Meckel's cave in the middle cranial fossa. These two nerves, vidian and V2, are separated by a pyramidal shaped bone and its apex marks the ICA. CONCLUSION: Our anatomical model provides the means to learn the endoscopic anatomy of the PPF and may be used for the simulation of surgical techniques. An endoscopic endonasal approach provides adequate exposure to all anatomical structures within the PPF. These structures may be used as landmarks to identify and control deeper neurovascular structures. The significance is that an anatomical model facilitates learning the surgical anatomy and the acquisition of surgical skills. A dissection superficial to the vascular structures preserves the neural elements. These nerves and their bony foramina, such as the vidian nerve and V2, are critical anatomical landmarks to identify and control the ICA at the skull base.     

鼻内镜下经鼻径路解剖翼腭窝区临床观察

目的 研究鼻内镜下经鼻径路观察翼腭窝区的临床解剖特点, 以期为手术提供参考。方法 5例(10侧)成人尸头标本经乳胶灌注后, 在0°鼻内镜下分别经蝶腭孔和上颌窦后壁两种手术径路显露翼腭窝, 再开放蝶窦, 充分暴露视神经、颈内动脉及蝶窦外侧壁相关结构, 观察各解剖结构的三维立体关系。结果 不同手术径路显露翼腭窝的范围不同, 祛除上颌窦内侧壁后能最大程度显露翼腭窝内所有解剖结构, 开放蝶窦后能观察翼腭窝与蝶窦区域相关结构的解剖关系。结论 只要熟悉鼻内镜下翼腭窝及邻近区域的解剖结构及关系, 选择合适的病例, 鼻内镜下经鼻行翼腭窝区手术是安全可行的。     

Transantral sphenopalatine artery ligation

Posterior epistnxis from branches of the sphenopalatine artery can be rapidly and effectively controlled by a new ligation technique. The sphenopalatine artery or its branches arc directly ligated as they exit the sphenopalatine foramen to enter the nose, completely avoiding the pterygomaxillary fossa. The vessels are exposed via a transantral approach, through the posterior portion of the medial antral wall. The mucoperiosteum of the lateral wall of the nose (medial antral wall) is preserved, elevated medially and posteriorly and used to tense the sphenopalatine vessels, bringing them into view and accessible for ligation at the foramen. Advantages of this technique include direct, specific ligation of the end vessels; ease and speed of operation; and avoidance of complications associated with the pterygomaxillary space. The technique was defined in multiple dissections of anatomic specimens and has been successful to date in 14 cases of severe posterior epistaxis.     

The superior petrosal triangle as a constant anatomical landmark for subtemporal middle fossa orientation

OBJECTIVES/HYPOTHESIS; Anatomical landmarks including the arcuate eminence and the superficial petrosal nerve serve as orienting landmarks for middle fossa dissection. However, because of considerable variation among patients, these landmarks are not always readily identifiable. We expand on a previously described method for identifying the head of the malleus as a constant anatomical landmark to optimize exposure when employing a middle fossa approach. METHODS; We completed an anatomical study using 10 preserved human cadaveric temporal bones to define the anatomical relationship among the root of the zygoma, the posterior-lateral lip of the foramen spinosum, and the bony tegmen over the head of the malleus. Subsequently, 5 fresh whole human cadaveric heads (10 temporal bones) were dissected using a surgically oriented anterior petrosectomy-middle fossa approach to evaluate the consistency of localizing the head of the malleus. RESULTS; We defined the superior petrosal triangle as a stable anatomical relationship. Our cadaveric data demonstrated that the distance from the root of the zygoma to the head of the malleus was 18.7 mm (SD = 1.7 mm) and the distance from the foramen spinosum to the head of the malleus was 19.2 mm (SD = 1.0 mm). The intersection of an arc transcribed 19 mm from the root of the zygoma and an arc transcribed 19 mm from the foramen spinosum localized the head of the malleus within 2.5 mm (SD = 2.4 mm). CONCLUSIONS: The landmarks defined by the superior petrosal triangle represent a means to localize the bony tegmen over the head of the malleus. Identification of the head of the malleus as a landmark in middle fossa surgery when other landmarks are not recognizable optimizes patient safety and surgeon confidence during complex surgical procedures.     

内镜下经眶外下壁入路颅底手术应用解剖研究初探

目的通过尸头解剖来探索经眶外下壁入路内镜手术所能达到的解剖通道、解剖标志及解剖方法等。方法对5具尸头（10侧）进行内镜下经眶外下壁入路颅底手术的细分解剖,通过逐步解剖来界定该入路所能达到解剖通道、颅内外重要解剖标志、解剖边界等。结果本研究界定了内镜下经眶外下壁入路颅底手术所能达到的5个通道,它们分别是三叉神经通道、破裂孔通道、海绵窦通道、岩锥及后颅窝通道、中颅窝通道,它们的边界、解剖标志、解剖通道、解剖步骤及方法都得以明确的界定。结论内镜下经眶外下壁入路颅底手术可以到达旁中线颅底、中颅窝,甚至是部分侧颅底及后颅窝,而且对于上颌神经、下颌神经颅内外段的暴露能提供很好的视野。当然,这还需要进一步的解剖研究及临床实践加以完善及检验。     

Anatomical landmarks for transnasal endoscopic skull base surgery

Resection of midline skull base lesions involve approaches needing extensive neurovascular manipulation. Transnasal endoscopic approach (TEA) is minimally invasive and ideal for certain selected lesions of the anterior skull base. A thorough knowledge of endonasal endoscopic anatomy is essential to be well versed with its surgical applications and this is possible only by dedicated cadaveric dissections. The goal in this study was to understand endoscopic anatomy of the orbital apex, petrous apex and the pterygopalatine fossa. Six cadaveric heads (3 injected and 3 non injected) and 12 sides, were dissected using a TEA outlining systematically, the steps of surgical dissection and the landmarks encountered. Dissection done by the “2 nostril, 4 hands” technique, allows better transnasal instrumentation with two surgeons working in unison with each other. The main surgical landmarks for the orbital apex are the carotid artery protuberance in the lateral sphenoid wall, optic nerve canal, lateral optico-carotid recess, optic strut and the V2 nerve. Orbital apex includes structures passing through the superior and inferior orbital fissure and the optic nerve canal. Vidian nerve canal and the V2 are important landmarks for the petrous apex. Identification of the sphenopalatine artery, V2 and foramen rotundum are important during dissection of the pterygopalatine fossa. In conclusion, the major potential advantage of TEA to the skull base is that it provides a direct anatomical route to the lesion without traversing any major neurovascular structures, as against the open transcranial approaches which involve more neurovascular manipulation and brain retraction. Obviously, these approaches require close cooperation and collaboration between otorhinolaryngologists and neurosurgeons.     

经鼻内镜翼腭窝和颞下窝应用解剖学研究

目的探索经鼻内镜翼腭窝、颞下窝恒定的解剖标志,为手术处理该区域病变奠定基础。方法对11例尸头行鼻内镜侧颅底解剖学研究。经鼻内镜经中鼻道、蝶腭孔、上颌窦后壁入路,暴露翼腭窝及颞下窝的重要血管、神经及骨性解剖标志,并测量各解剖标志间的距离。结果经鼻内镜可恒定暴露蝶腭孔、翼管、圆孔、蝶腭神经节、眶下神经、卵圆孔、棘孔等重要侧颅底标志。鼻小柱基底到蝶腭孔、翼管、圆孔、卵圆孔、棘孔、破裂孔的距离分别为（69±3）、（73±3）、（75±3）、（90±5）、（96±4）、（88±3）mm。结论经鼻内镜可显露翼腭窝及颞下窝重要解剖结构,且各解剖结构可通过相互之间的距离及位置在鼻内镜二维平面上互相定位,以更直观、安全的处理该区域的病变。     

蝶腭孔的显微解剖学研究

目的 :通过对尸颅蝶腭孔的测量和观察 ,为经鼻内镜蝶腭孔相关手术提供解剖学依据。方法 :应用显微解剖学方法对 4 0侧正中线切开的尸颅蝶腭孔进行了位置、形状、大小及毗邻关系的观察与有关数据的测量。结果 :将蝶腭孔分成 3类 ,Ⅰ类 :孔位于上鼻甲、上鼻道的后方 ,Ⅱ类 :孔位于中鼻甲或中鼻道的后端 ,Ⅲ类 :Ⅰ类加Ⅱ类。各类分别占 35 %、5 %、6 0 %。孔上缘与蝶窦底间距离男 (1.75± 1.10 )mm ,女 (1.13± 0 .5 5 )mm ,与蝶窦口距离男 (9.80± 3.2 7)mm ,女 (8.30± 3.4 5 )mm ,孔的后缘与鼻咽部距离男 (11.12± 3.30 )mm ,女 (10 .85± 3.12 )mm ,孔的前缘与上颌窦口距离男 (18.5 0± 6 .‘80 )mm ,女 (14 .5 7± 5 .0 7)mm ,与鼻尖距离男 (6 9.5 4± 6 .98)mm ,女(6 6 .5 7± 5 .0 7)mm ,与前鼻棘距离男 (5 6 .6 9± 5 .70 )mm ,女 (5 3.2 5± 8.80 )mm ,以蝶腭孔中心点为准前后径女(4 .6 1± 1.80 )mm ,男 (5 .12± 2 .0 5 )mm ,上下径男 (5 .37± 2 .6 7)mm ,女 (4 .74± 2 .74 )mm ,与硬腭水平板的夹角男(2 2 .83± 4 .71)°,女 (2 2 .73± 3.81)°。蝶腭动脉外径男 (2 .12± 0 .6 6 )mm ,女 (1.6 1± 0 .70 )mm ,蝶腭神经外径男(0 .6 5± 0 .4 9)mm ,女 (0 .35± 0 .0 7)mm。鼻腔外侧壁的血供及     

翼腭窝和颞下窝三维影像学与经鼻内镜解剖学对照研究

目的 探讨多层螺旋CT(multislice spiral computed tomography,MSCT)测量翼腭窝和颞下窝解剖相关标志的方法及可行性.方法 对11具尸头行MSCT扫描,利用工作站确立解剖标志空间坐标,并计算解剖学数据.同时对11具尸头经鼻内镜解剖翼腭窝和颞下窝,并测量相关解剖学数据,对照影像学与鼻内镜下的共同解剖标志的形态,比较影像学和鼻内镜下解剖测量数据结果.结果 影像学方法和解剖学方法测量得到鼻小柱根部到蝶腭孔、翼管、圆孔、卵圆孔、棘孔、颈动脉管外口、破裂孔的距离((-x)±s,下同)分别为:(68.83±3.00)、(72.49±2.88)、(75.26±3.14)、(88.55±5.00)、(95.19±4.31)、(106.76±3.77)、(88.16±2.87)mm和(68.90±3.04)、(72.73±3.08)、(75.44±3.07)、(89.75±4.13)、(96.22±3.37)、(106.68±3.75)、(88.47±2.64)mm,两组数据差异无统计学意义(t值分别为-0.856、-1.134、-0.920、-1.923、-1.903、2.820、1.209,P值均>0.05).蝶腭孔、翼管、圆孔、卵圆孔、颈动脉管外口、破裂孔是鼻内镜解剖和影像学共同的解剖标志,可作为判断翼腭窝和颞下窝内神经、血管以及重要毗邻结构空间关系的解剖标志.结论 MSCT扫描三维重建测量翼腭窝和颞下窝相关标志解剖学数据可靠,可为临床个体化手术提供依据.     

High-resolution computed tomography analysis of the greater palatine canal

BACKGROUND: The greater palatine foramen injection is effective for minimizing bleeding during sinus surgery. The correct depth is important to minimize risk of orbital penetration. This study analyzed the length of the greater palatine canal using high-resolution computed tomography (HRCT). METHODS: HRCT sinus scans from 100 adults were analyzed. One thousand two hundred measurements were performed by three observers. RESULTS: The mean distance of the greater palatine foramen to the orbital floor was 40+/-3 mm in men and 37+/-3 mm in women (range, 32-46 mm). The mean distance of the greater palatine foramen to the sphenopalatine foramen was 28+/-2 mm in men and 27+/-2 mm in women (range, 23-33 mm). CONCLUSION: The greater palatine foramen injection is an appropriate method to minimize bleeding during endoscopic sinus surgery. The authors recommend an injection depth of 25 mm in adults to minimize the risk of intraorbital complications.     

鼻内镜手术颌内动脉翼腭段的应用解剖

目的：研究颌内动脉翼腭段的走行及分支规律,为经鼻内镜手术过程中合理处理颌内动脉提供解剖学依据。方法：10具去脑颅底骨正中裂开,显微镜下解剖蝶腭动脉,经鼻内镜上颌窦入路开放翼腭窝,暴露颌内动脉翼腭段所有分支,将上颌窦后、内壁交界的凹陷定义为A点,通过眶下孔的水平线与上颌窦前壁、后外侧壁交线相交于B点,上颌窦前壁、后外侧壁和底壁的交点为D点,BD连线的中点为C点,颌内动脉翼腭段发出的第一分支点为C′点,观察其分支及走行规律。结果：蝶窦口下缘到鼻后中隔上动脉的距离为（5．88±2．21）mm;C′点位于AC上13侧,占65%（13／20）;位于AB上5侧,占25％（5／20）;位于AD上1侧,占5％（1／20）;高于AB1侧,占5％（1／20）。结论：熟悉颌内动脉的分支及走行对于治疗顽固性鼻出血和翼腭窝手术有重要意义;本实验中利用A、B、C、D点为参照点确定颌内动脉走行的方法,有助于内镜经鼻（上颌窦）手术中颌内动脉的定位及结扎处理。     

泪囊鼻腔吻合术中泪骨的定位测量

目的:探讨泪骨在泪囊鼻腔吻合术中的重要意义。方法:测量10具(男5具,女5具)成人尸头鼻腔外侧壁上泪骨的长、宽、厚,观察钩突、上颌线和M点(上颌线的中点)的解剖位置。结果:泪骨在鼻腔外侧壁位于钩突的前方,骨质菲薄,所测量的长、宽、厚的平均值分别为9.23、3.63和0.06 mm。结论:使用咬钳可以咬除泪骨,进一步开放泪囊内壁骨质,同时避免使用电钻,减小创伤。钩突、上颌线及M点可作为术中可靠的定位标志。     

Endoscopic anatomy of the sphenopalatine and posterior nasal arteries: implications for the endoscopic management of epistaxis

BACKGROUND: Refractory posterior epistaxis is a challenge for otolaryngologists. Most algorithms for managing this condition ultimately call for interrupting the arterial blood supply to the nasal mucosa. Traditionally, this was accomplished either by transantral arterial ligation or by arteriographic-guided embolization. More recently, the endonasal endoscopic approach has also been described. Because the primary blood supply to the posterior nasal cavity is derived from the terminal branches of the sphenopalatine and the posterior nasal arteries, we conducted this anatomic study to examine and describe the anatomic relationship of these two arteries as they exit the pterygopalatine fossa and enter the nasal cavity. METHODS: We performed endoscopic dissections of this anatomic region in nine fresh and one formalin-preserved cadaver specimens. A total of 19 sides were examined. RESULTS: In 3 of 19 specimens (16%), the sphenopalatine artery branched from the sphenopalatine artery within the sphenopalatine canal, allowing the two arteries to exit together. In 8 of the 19 specimens (42%), the sphenopalatine artery exited much more posteriorly, yet from within a shared posteriorly elongated sphenopalatine foramen. In the remaining eight specimens (42%), the sphenopalatine artery exited through a distinct foramen directly posterior to the larger sphenopalatine foramen. CONCLUSION: Understanding this anatomic relationship is important in performing endoscopic arterial ligation. If the sphenopalatine artery is not specifically identified and ligated, an important component of the posterior nasal circulation will not be addressed adequately by this surgical approach.     

鼻内镜下经鼻腔入路翼腭窝解剖学研究

目的：通过鼻内镜下鼻腔外侧壁入路对翼腭窝的解剖学研究,为临床内镜下翼腭窝手术入路提供解剖学基础。方法：10具新鲜尸头采用内镜下鼻腔外侧壁入路对翼腭窝进行解剖,观测手术径路中重要标志及穿经血管神经结构,并观测翼腭窝内结构及其与周围结构的关系。结果：①翼腭窝及其周围结构解剖关系复杂,颌内动脉及其分支变异较大;②蝶腭孔、眶下管、圆孔和翼管是翼腭窝重要骨性标志,同时翼腭窝可作为进入颞下窝和蝶窦的通路。结论：①熟知翼腭窝及其周围恒定的解剖标志可保持方向感,提高手术安全性;②鼻内镜下经鼻腔外侧壁入路可充分暴露翼腭窝,视野清晰,术中对重要神经血管控制较好,可根据病变范围变通手术径路;③经鼻内镜下鼻腔外侧壁入路可进入翼腭窝临近区域,处理临近区域病变。     

Endoscopic endonasal study of the maxillary nerve: a new orientation

BACKGROUND: Endoscopic endonasal procedures for advanced lesions involving the pterygopalatine fossa (PPF) and its various communications are increasingly performed. The maxillary division of the trigeminal nerve (V2) passes through the foramen rotundum and crosses the upper part of the PPF, with a risk of partial or complete injury during surgery in this complex region. Despite the available knowledge of the sinonasal anatomy, the endoscopic orientation of the V2 remains unclear and requires further analysis from this unique view. METHODS: Using an extended endoscopic approach, the PPF was dissected in 20 sides of 10 adult cadaver heads. The V2 also was followed anteriorly from the trigeminal ganglion, toward the infraorbital canal. The course and the neurovascular relationships of the V2 were studied. High-quality endoscopic images have been produced by coupling the video camera to a digital video recording system. RESULTS: The endoscopic course and relations of the V2 were carefully described. Important landmarks to identify and avoid injury of the nerve were discussed in relation to this unique view. CONCLUSION: This study updates our understanding of the V2 anatomy from an endoscopic perspective. The medial to lateral inclination and drooping of the V2, as well as different relationships of the V2 with the vascular structures are important findings to be taken into consideration while endoscopically addressing related lesions.