【作者】 吴云霞；

【导师】 康德智； 许家军； 王玮；

【作者基本信息】 福建医科大学 ， 外科学， 2008， 硕士

【摘要】 【目的】探讨视觉假体微电极芯片植入视神经的相对安全区,为临床视神经手术提供解剖学依据。【方法】30例成人头颅标本,动脉灌注混有红色染料的乳胶,观测视神经周围主要血管、神经的行程和外径等数据;4例新鲜成人头颅标本(动脉灌注墨汁混合液),球后4～8mm视神经连续切片,片厚20μm,显微镜观察和Image Advanced 3.0测量神经横断面中各象限血管断面数和血管的总面积,并进行统计学处理。【结果】在眶外侧可见外直肌上缘(3.83±1.43)mm处有泪腺动脉和神经与其伴行向前至泪腺。将外直肌向下牵引,显露视神经,两者之间的间隙称为外直肌—视神经间隙,其深度为(8.14±0.90)mm,主要有睫状短神经和颞侧睫状后动脉等结构穿行。在眶上方,可见眼动脉多数起始于颈内动脉,视网膜中央动脉由眼动脉发出后主要经下方穿入视神经,穿入处距球后(0.85±0.28)cm,其中距离≤4mm者19.2%,≥8mm者76.9%,球后6.5mm处穿入者3.9%。鞘动脉穿入鞘膜的方位,内侧20%,上方29.3%,外侧6.7%,下方44%。在球后与总腱环中点处,视神经左右径(3.96±0.35)mm,上下径(4.18±0.33)mm。在碳素墨汁混合液灌注的新鲜标本上还观察到,视神经鞘上分布着丰富的血管网,血管在鞘膜上大致呈前后纵向走行。取球后4～8mm段视神经连续切片,显微镜下发现,鞘膜的血管网向神经实质内以近似直角的方式向中心发出许多小支,呈向心性走行。调整、校正后Image Advanced 3.0软件分析视神经实质内各象限血管断面数和血管的总面积,小血管的断面数为( 178.936±8.666 ) ,血管总面积为(0.001280±0.000035)mm2,各象限间无显著差异。【结论】1、经眶外侧壁入路显露视神经的手术中,要注意保护外直肌上缘的泪腺动脉和神经,以免影响泪腺的功能。暴露视神经时需经过外直肌—视神经间隙,手术显露视神经时应注意保护该间隙结构。2、在球后4～8mm间植入微电极芯片或进行视神经手术较为安全。3、经外侧植入视觉假体微电极芯片或进行其它视神经手术可最大限度的减少对视神经血供的影响。4、视神经外径约4mm,视网膜中央动脉在视神经实质中央呈前后纵向走行,微电极芯片最好沿神经纵行植入,且植入深度不宜过深,以免影响视网膜血供。5、因外伤或植入微电极芯片等原因造成视神经缺血所致的神经纤维受损不存在象限的差异。更多还原

【Abstract】 【Objective】To investigate the relatively safe area of implanting vision prosthesis microelectrode to optic nerve,and to provide anatomic data for operations of optic nerve.【Methods】The courses and external diameters of the arteries and nerves were observed and measured on thirty adult cadaver heads, which were formalized and vascular cast by red emulsion. Four cases of freezed adult cadaver heads(intra-arterial infusion mixed liquids of prepared Chinese ink), the optic nerve that 4～8mm posterior to eyeball was cut in serial sections 20μm in thick. The vessel section count(VSC) and vessel section surface area(VSS) in the 4 quadrants of transverse sections of optical nerve were counted and measured by microscope and Image Advanced 3.0,then data were analyzed using SPSS 13.0.【Results】Opened the lateral orbital wall and paries superior orbitae of adult cadaver heads.From the lateral orbital wall lacrimal artery and nerve went forword to lacrimal gland at (3.83±1.43)mm above the superior margin of external rectus muscle. The interspace between the external rectus muscle and the optic nerve was called external rectus muscle-optic nerve inter- space.There were short ciliary nerves and posterior ciliary artery through it , and its depth was (8.14±0.90)mm. Most of the central retinal artery (CRA) entered optic nerve from the bottom of the nerve, where was behind the eyeball(0.85±0.28)cm, the distance≤4mm was 19.2%,≥8mm was76.9%,entered behind the eyeball 6.5mm was 3.9%. The position of the sheathed arterioles penetrating sheath of optic nerve was :medial 20%,superior 29.3%,lateral 6.7%,inferior 44%. The transverse and vertical diameter of optic nerve were (3.96±0.35)mm and (4.18±0.33)mm at the midpoint between the annulus tendineus communis and posterior pole of eyeball.It was observed from adult cadaver heads(infused with mixed liquids of prepared Chinese ink) that there were plenty of microarteries on the optic nerve sheath,which anastomosed each other and run longitudinaly and anterior-posteriorly. By microscope, it was observed that there was vascular network on the sheath, which erupting small branches to the center of the nerve by vertical mode and the segmental microarterial lay centrally to their corresponding arterioles..The number of cross section of microvasculature was (178.936±8.666),the average of cross section of was (0.001280±0.000035) mm2,and there were no significant differences between the varies quadrants.【Conclution】1. To protect the lacrimal artery and nerve above on the superior margin of external rectus muscle when the optic nerve was exposed in the operation. Pay attention to the structures among the interspace between external rectus muscle and optic nerve.2. It would be safer to implant microelectrode or operate on the optic nerve where was 4～8mm behind the eyeball.3. To minimize the damage to the blood supply of optical nerve, the vision prosthesis microelectrode should be implanted through the lateral of optical nerve.4. The outer diameter of optic nerve was about 4mm,and the CRA run lengthways and anterior-posteriorly in the center of optic nerve. To avoid retinal ischemia,the vision prosthesis microelectrode should be implanted lengthways,and too deeply incision was not suitable.5. There were no differences among the blood supply of each quadrant of optic nerve when it was damaged by traumatism or implanting microelectrode.更多还原