额鼻锁孔入路的设计与临床实践

A study on the surgical approach of trans-frontonasal keyhole

目的设计适用于颅底鞍上中线区域、突入第三脑室前部甚至达室间孔以上水平肿瘤的手术入路。方法 3例实体颅骨解剖测量明确额鼻缝宽度、两侧眶上切迹间距离、额鼻缝中点至两侧眶上切迹连线中点的距离。MRI测量额窦底部水平线与额窦底部至室间孔连线的夹角,同时测量额窦底部至室间孔距离。3例第三脑室前部肿瘤切除临床验证该入路可行性。结果 (1)额鼻部骨性结构测量:额鼻缝平均宽度2.8 cm,两侧眶上切迹平均间距5.2 cm,额鼻缝中点至两侧眶上切迹连线中点平均距离1.4 cm。(2)MRI显示额窦底部水平线与额窦底部至室间孔连线夹角平均24°,深度平均距离6.5 cm。(3)手术设计为"U"形切口,经该入路锁孔显微手术可全切肿瘤。结论额鼻锁孔手术入路以额鼻缝为骨性标志点,相关局部解剖满足锁孔手术的骨窗要求,经该入路利用自然间隙可直达第三脑室与室间孔区域,实现以最小损伤取得最大疗效的手术目的。

Objective To design the surgical approach for the tumor located in the suprasellar region, anterior area of the third ventricle,even over the interventricular foramen. Methods Three patients received bone anatomical measurement for the width of the frontonasal suture the distances between the bilateral supraorbital notches and the distance from the midpoint of the frontonasal suture to the midpoint of the line between the bilateral supraorbital notches. The angle of the horizontal line at the bottom of the frontal sinus and the line from the bottom of the frontal sinus to the interventricular foramen and the distance between the bottom of the frontal sinus and the interventriculare foramen were measured by MRI. The resection of the tumor in the anterior third ventricle region in the 3 patients validated the feasibility of the approach clinically. Results（1） The width of the frontonasal suture was 2.8 cm in average. The space between the bilateral supraorbital notches was 5.2 cm in average. The distance from the midpoint of the frontonasal suture to the midpoint of the line between the bilateral supraorbital notches was 1.4 cm in average.（2）MRI results showed that the average angle was24° between the horizontal line at the bottom of the frontal sinus and the line from the bottom of the frontal sinus to the interventricular foramen, and the average distance was 6.5 cm.（3） ＂U＂ shaped incision was designed for the surgery. Through the keyhole approach the tumor could be completely removed. Conclusions The frontonasal suture is the bony landmark for trans-frontonasal keyhole. The relevant local anatomy meets the requirements of the keyhole microsurgery. The third ventricle and the interventricular foramen area can be accessed by means of the natural gap. The surgical approach can decrease the risk and surgical damage and achieve optimal surgical outcome.