三脑室手术入路的显微解剖研究

目的:通过研究经前额-纵裂至第三脑室入路的显微解剖结构,为临床切除第三脑室肿瘤提供解剖学依据。方法:15具成人尸头,在显微镜下经前额-纵裂至第三脑室进行解剖,熟悉相关解剖结构。结果:冠矢点位置较为恒定,可作为手术入路的切口定位标志。胼胝体参与侧脑室各个壁的构成;透明隔在中线上分开侧脑室的额角和体部;穹窿是侧脑室壁上围绕在丘脑周围的结构;脉络膜裂是三脑室手术的入路部位。脑室内静脉是手术中重要的解剖标志。大脑深部静脉是手术入路的最大障碍。结论:经前额-纵裂至第三脑室入路经生理间隙进入,对周围结构损伤小,是切除第三脑室肿瘤的较佳人路。     

经前额纵裂入路的神经内镜与显微解剖学及临床应用

目的通过对经前额纵裂入路的内镜解剖与显微解剖学研究,为临床提供解剖学参考。方法8例成人尸头,取经前额纵裂入路,在显微镜和内镜下对其内部结构进行全程观察。采用经前额纵裂入路手术22例。结果通过显微镜及不同角度内镜,能够观察到鞍区和第三脑室结构。22例中,动脉瘤5例均成功夹闭,肿瘤全切13例,近全切除3例,大部切除1例,无死亡病例,无严重并发症的发生。结论内镜辅助显微镜经前额纵裂入路对鞍区及第三脑室前部暴露良好,对周围组织损伤小,是切除鞍区和第三脑室前部肿瘤的较佳入路。     

幕上脑室的神经内镜应用解剖学研究

目的　研究脑室的神经内镜应用解剖学特点 ,探讨其临床应用价值。方法　在 16例尸颅标本、2 0例脑积水患者手术中用神经内镜观察侧脑室、三脑室的解剖结构。其中在尸颅标本采用经侧脑室额角、枕角和三脑室后部入路观察脑室 ;在脑积水患者中均采用经额角入路。结果　经额角入路观察侧脑室体部、枕角 ,三脑室底部、后部 ;经枕角观察到从颞角到额角的脉络丛。在侧脑室内观察的重要“路标”是室间孔处的Y形结构。结论　经额角入路观察范围最大 ,是脑室内神经内镜手术的最常用入路 ,经此入路可以同时完成多种手术。经枕角观察到的脉络丛最多 ,是脉络膜电凝术的最佳入路     

第三脑室前半部肿瘤经纵裂终板人路

第三脑室肿瘤的手术入路,自Dandy以来,有各种入路,即Dandy的切除右额叶经Monro孔入路,Poppen的切开右额叶经Monro孔入路、Van Wagenen枕叶切开经侧脑室入路,Dandy的经胼胝体松果体部肿瘤摘除,Jamieson的枕下经小脑幕入路,Steln的幕下小脑上入路等.不论做法如何都要避免损伤脑实质,特别是第三脑室周围重要组织,而且极力避免牺牲动静脉,否则术后将产生严重合并症.为了摘除第三脑室肿瘤,无论如何不应损伤第三脑室壁,终板是第三脑室最薄的部分,即视交叉后视     

联合入路显微手术切除巨大侵袭性垂体腺瘤

目的探讨一种巨大侵袭性垂体腺瘤的联合入路显微手术切除方法。方法1997年至2003年对14例体积巨大、肿瘤由鞍内向鞍上、第三脑室及侧脑室内生长的侵袭性垂体腺瘤，采用经侧脑室及经额下或经纵裂联合入路一期手术治疗。结果4例肿瘤全切除，9例次全切除，1例大部切除。本组病人无死亡结论选择合适病例采用一次性联合入路显微手术切除巨大侵袭性垂体腺瘤，可以提高手术切除率，降低死亡率和致残率。     

内镜和显微镜下经鼻入路鞍区的解剖学对比研究

目的 研究对比神经内镜和手术显微镜经单鼻孔鼻内-蝶窦入路的解剖特点,为临床应用提供解剖学理论依据.方法 福尔马林浸泡固定的尸头10例,彩色乳胶灌注动脉系统.模拟经鼻内入路鞍区手术,先用显微镜,然后更换为内镜观察并测量相关解剖结构.结果 内镜相比显微镜:在蝶鞍水平区域,鞍旁术野同侧和对侧分别增加平均5.0 mm和6.5 mm的显露范围;前颅底区域,矢状位增加4.0 mm,横向同侧、对侧增加3.5 mm、4.0 mm;斜坡后颅底区域,都能显露对侧的斜坡旁颈内动脉隆起,而向两侧观察,内镜的显露范围平均同侧增加4.0 mm,对侧2.5 mm.结论 内镜可以提供一种全景的术野,从而扩展了经鼻入路显微手术的显露范围,尤其适用于简化和扩大经鼻内八路鞍区手术.     

内镜和显微镜下经鼻入路鞍区的解剖学对比研究

目的 研究对比神经内镜和手术显微镜经单鼻孔鼻内-蝶窦入路的解剖特点,为临床应用提供解剖学理论依据.方法 福尔马林浸泡固定的尸头10例,彩色乳胶灌注动脉系统.模拟经鼻内入路鞍区手术,先用显微镜,然后更换为内镜观察并测量相关解剖结构.结果 内镜相比显微镜:在蝶鞍水平区域,鞍旁术野同侧和对侧分别增加平均5.0 mm和6.5 mm的显露范围;前颅底区域,矢状位增加4.0 mm,横向同侧、对侧增加3.5 mm、4.0 mm;斜坡后颅底区域,都能显露对侧的斜坡旁颈内动脉隆起,而向两侧观察,内镜的显露范围平均同侧增加4.0 mm,对侧2.5 mm.结论 内镜可以提供一种全景的术野,从而扩展了经鼻入路显微手术的显露范围,尤其适用于简化和扩大经鼻内八路鞍区手术.     

内镜和显微镜下经鼻入路鞍区的解剖学对比研究

目的 研究对比神经内镜和手术显微镜经单鼻孔鼻内-蝶窦入路的解剖特点,为临床应用提供解剖学理论依据.方法 福尔马林浸泡固定的尸头10例,彩色乳胶灌注动脉系统.模拟经鼻内入路鞍区手术,先用显微镜,然后更换为内镜观察并测量相关解剖结构.结果 内镜相比显微镜:在蝶鞍水平区域,鞍旁术野同侧和对侧分别增加平均5.0 mm和6.5 mm的显露范围;前颅底区域,矢状位增加4.0 mm,横向同侧、对侧增加3.5 mm、4.0 mm;斜坡后颅底区域,都能显露对侧的斜坡旁颈内动脉隆起,而向两侧观察,内镜的显露范围平均同侧增加4.0 mm,对侧2.5 mm.结论 内镜可以提供一种全景的术野,从而扩展了经鼻入路显微手术的显露范围,尤其适用于简化和扩大经鼻内八路鞍区手术.     

额外侧锁孔入路的显微与神经内镜解剖

目的对比研究前颅底的显微解剖与神经内镜解剖，为额外侧锁孔手术入路处理前颅底、鞍区病变提供解剖基础。方法经额外侧锁孔手术入路对15具成人尸头进行显微解剖和神经内镜下解剖，比较两种解剖所暴露的范围。结果显微解剖在嗅沟、鞍区和外侧裂存在一定范围的视野盲区；内镜有充足的照明，可将手术视野放大，无视野盲区，清楚地显示周围的解剖结构，而且看得更远。但内镜的图像为二维图像，缺乏景深。神经内镜辅助显微手术可以互补各自不足。结论额外侧锁孔入路在神经内镜的辅助下显微手术切除前颅底和鞍区的病变安全、微创。     

第三脑室肿瘤手术治疗的体会

目的:探讨第三脑室肿瘤手术治疗的方法。方法:分析总结手术治疗27例第三脑室肿瘤的临床资料。结果:全切肿瘤9例,次全切13例,部分切除5,死亡1例。结论:第三脑室前部、中部、后部肿瘤分别取胼胝体前部入路,侧脑室脉络体下入路,胼胝体后部入路为宜。     

Endoscopic approaches for third ventricular tumors

Endoscopic approaches for third ventricular tumors, both transcortical and transcallosal approaches, are described. A 4-mm diameter, 0-degree rod-lens endoscope is used in both procedures, and angled rod-lens endoscopes are used for angled views. The transcortical transventricular approach is made via a burr hole placed at the nondominant frontal area, 1-inch lateral to the midline along the coronal suture. A folded vinyl tube, which can be expandable to a 1-cm tube by unfolding, is placed into the lateral ventricle toward the tumor under an image-guidance system. The transcallosal approach is made via a burr hole placed along the lateral margin of the superior sagittal sinus at the nondominant frontal area. The surgical corridor is made along the interhemispheric fissure. A rolled, cigarette-shaped, cotton patty is placed anteriorly and posteriorly along the surgical trajectory to keep the corridor open. The corpus callosum is opened, and the tumor is removed with surgical instruments inserted through the supported corridor parallel with the endoscope, which is mounted to an endoscope holder. Endoscopic transcortical and transcallosal approaches for the removal of third ventricular tumors are described. Compared with endoscopy performed through fixed working-channels, these techniques increase flexibility for surgeons to maneuver surgical instruments for delicate microdissection and tumor removal.     

Surgical anatomy and surgical approaches of the third ventricle

Careful analysis of MRI images is mandatory before any surgical procedure in the third ventricle. This analysis should take in account the relationship of the tumor itself, but also the grade of hydrocephalus and the main anatomical landmarks along the surgical approach. The first step is the access to the lateral ventricle, which may be achieved via transcortical or anterior transcallosal routes : these two operative procedures are detailed. The transforaminal entry to the third ventricle may be easy if hydrocephalus has widened the foramen of Monro. In other cases, a subchoroidal (or interthalamo-trigonal) approach is necessary, and the division of the thalamostriate vein is sometimes required. In this series, the transcortical route has been favoured by neurosurgeons. The advantages and drawbacks of both transcortical and anterior transcallosal routes are discussed. The anterior interhemispheric and pterional approaches are briefly evoked, as they were used in very few cases of this series. The management of hydrocephalus is discussed.     

Epidermoid of the third ventricle--report of a case

A rare case of epidermoid of the third ventricle was experienced. The patient was a fifteen years old boy, who had been hospitalized four years earlier due to acute hydrocephalus. The ventriculography at that time revealed a large cystic tumor containing heterogeneous mass filling the entire third ventricle, which seemed to be a dermoid or epidermoid. Ventricular drainage and ventriculo-peritoneal shunt were performed and he was discharged one month later without any complaint. On February 10th 1983, he was re-admitted with severe headache, nausea and showing markedly increased intracranial pressure and right hemianopsia. Computerized tomography scans demonstrated a large round low density mass in the entire third ventricle extending into the prepontine cistern. Radical operation was performed by the anterior transcallosal approach. After dissecting the interhemispheric fissure, a longitudinal incision about 15 mm long was made in the anterior part of the corpus callosum and the tumor was removed. Mild diabetes insipidus and subdural effusion appeared postoperatively. The patient was discharged on April 7th with right hemianopsia and returned to school. The anterior transcallosal approach seemed to be a good operative procedure in such large third ventricle tumor cases since it allowed excellent exposure of the third ventricle and minimized postoperative neurological deficits.     

The Transcallosal Anterior Interfoniceal Approach: A Microsurgical Anatomy Study

Objectives A plethora of surgical strategies have been described to reach deep-seated lesions situated within the third ventricle including the Rosenfeld, or transcallosal anterior interfoniceal (TAIF), approach. First introduced in 2001, it consists of a small callosotomy followed by the midline transseptal dissection of fornices to enter the roof of the third ventricle. The aim of this microsurgical anatomy study is to describe and show each stage of the surgical procedure, focusing on the possible trajectories to anatomical landmarks. Participants A total of 20 adult cadaveric specimens were used in this study. Using ×3 to ×40 magnifications, the surgical dissection was performed in a stepwise fashion, and the transcallosal anterior interforniceal approach was performed, analyzed, and described. Results In 5 specimens of 10, a cavum septum pellucidum was depicted. In 5 cases of 20 after the callosotomy ,the lateral ventricular cavities were reached. Different orientation of the microscope allowed us to define three surgical trajectories to visualize the region of interest without exposing important functional areas. Conclusion The TAIF represents a minimally invasive approach to the third ventricle; its tricky surgical steps make appropriate anatomical dissection training essential to become confident and skilled in performing this approach.     

Pre-coronal, paramedian minicraniotomy: a minimal access approach for microsurgical, transcallosal, transforaminal removal of colloid cysts of the third ventricle

OBJECTIVE: Microsurgical excision of colloid cysts of the third ventricle is accomplished along the transcallosal or the transfrontal routes. In the transcallosal approach, venous tributaries of the superior sagittal sinus can often act as an impediment to entry into the interhemispheric fissure for accessing the corpus callosum. We propose a paramedian minicraniotomy anterior to the coronal suture for removing colloid cysts via the transcallosal approach as veins are relatively rare in this area. METHODS: A triangular minicraniotomy was designed with each side measuring 3 cm based on the midline in the pre-coronal area of the frontal bone on the right side. Nineteen cases of symptomatic colloid cysts of the third ventricle whose diagnoses were proven by CT and/or MRI were subjected to microsurgery in the period from June 2004 to May 2007. Following the minicraniotomy the cysts were removed utilizing the transcallosal transforaminal route. RESULTS: Venous tributaries crossing the interhemispheric fissure were seen in 2 patients and these could be avoided to access the corpus callosum. Complete excision could be achieved in all cases. All patients had a good outcome although one patient had transient left lower limb weakness. The mean operating time was 163 minutes, while the mean duration of stay in the intensive care unit and hospitalization were 1.35 days and 3.73 days, respectively. CONCLUSION: The pre-coronal, paramedian minicraniotomy is safe and effective for the total excision of colloid cysts of the third ventricle. As a minimal access approach, it needs only a short duration of postoperative hospitalized care.     

Interactive image-guided transcallosal microsurgery for anterior third ventricular cysts.

Although the treatment of colloid cysts remains controversial, high viscosity and small volume are poor prognostic indicators for successful burr hole aspiration and cortical incision via craniotomy may be associated with postoperative epilepsy. The anterior transcallosal approach provides a direct and adequate pathway to the lateral ventricles, where the foramen of Monro serves as a natural entrance into the anterior third ventricle, especially when the foramen is dilated by a lesion. When the midsuperior portion of the IIIrd ventricle cannot be reached, the interforniceal or the subchoroidal exposures have been advocated. Stereotactic techniques contribute to a minimal invasive approach and reduce morbidity. Nine patients harbouring anterior third ventricular cysts (seven colloids and two intrinsic craniopharyngiomas) underwent anterior transcallosal microsurgical excision assisted by an interactive infrared-based image guided system (EasyGuide, Neuro, Philips). There were 4 men and 5 women ranging in age from 15 to 42 years (mean 28.5). Transcallosal transforaminal (5 cases) or interforniceal (4 cases) approaches allowed total excision in eight patients and subtotal in one. Postoperative morbidity included a case of transient hemiparesis and a case of transient short-term memory disturbances; both resolved in the first months. Mortality was zero. Particular advantages of the method were accurate trajectory and position of callosotomy incision determination, visualisation and avoidance of superior saggital sinus, retraction of bridging veins and the often variable pericallosal arteries, spatial orientation within the ventricular system, and identification of the periventricular anatomical structures.     

Microsurgical anatomy of the choroidal fissure

The microsurgical anatomy of the choroidal fissure was examined in 25 cadaveric heads. The choroidal fissure, the site of attachment of the choroid plexus in the lateral ventricle, is located between the fornix and thalamus in the medial part of the lateral ventricle. The choroidal fissure is divided into three parts: (a) a body portion situated in the body of the lateral ventricle between the body of the fornix and the thalamus, (b) an atrial part located in the atrium of the lateral ventricle between the crus of the fornix and the pulvinar, and (c) a temporal part situated in the temporal horn between the fimbria of the fornix and the lower surface of the thalamus. The three parts of the fissure are the thinnest sites in the wall of the lateral ventricle bordering the basal cisterns and the roof of the third ventricle. Opening through the body portion of the choroidal fissure from the lateral ventricle exposes the velum interpositum and third ventricle. Opening through the temporal portion of the choroidal fissure from the temporal horn exposes the structures in the ambient and crural cisterns. Opening through the atrial portion of the fissure from the atrium exposes the quadrigeminal cistern, the pineal region, and the posterior portion of the ambient cistern. The neural, arterial, and venous relationships of each part of the fissure are reviewed. The operative approaches directed through each part of the fissure are also reviewed.