Knosp分级和海绵窦分区在侵袭性垂体瘤经鼻内镜手术中的临床意义

The significance of Knosp classification and cavernous sinus division in endoscopic transnasal surgery for invasive pituitary adenomas

目的探讨Knosp分级和海绵窦分区对评价垂体瘤侵袭性和指导经鼻内镜手术的临床意义。方法 75例患者(Knosp分级3级44例、4级31例)均源自2015年7月至2017年6月住院行经鼻内镜手术的垂体瘤病例。术前通过鞍区冠状位MRI计算颈内动脉海绵窦段至前床突上段血管中点连线距离与肿瘤向鞍旁侵袭最远点至该连线垂直距离的比值(比值R)以判断Knosp分级3级垂体瘤的侵袭程度,然后根据内镜下海绵窦分区和海绵窦内侧壁是否受累将侵入不同海绵窦间隙的Knosp分级3级垂体瘤进一步分为3A级(侵袭性和非侵袭性)和3B级,从而制定手术方案。结果 Knosp分级3A级垂体瘤患者共36例,肿瘤呈侵袭性生长12例(主要侵入海绵窦后上间隙,影响动眼神经)、非侵袭生长24例(肿瘤推挤海绵窦内侧壁但未侵入,呈假侵袭),侵袭组比值R小于非侵袭组(1.28±0.18对1.74±0.27;t=5.275,P=0.000)。Knosp分级3A级患者中比值R≤1.59(中位值)者17例、>1.59者19例,前者肿瘤侵袭性高于后者(12/17对0/19;Fisher确切概率法:P=0.000)。75例患者中肿瘤全切除率72%(54/75),Knosp分级3级达84.09%(37/44)、4级为54.84%(17/31)。术后平均随访(14.84±5.66)个月,无一例复发。结论术前通过鞍区冠状位MRI计算比值R,有助于评价Knosp分级3A级垂体瘤侵袭程度,结合术中内镜下海绵窦分区,对经鼻内镜垂体瘤切除术具有重要指导意义。

Objective To evaluate the value of Knosp classification and cavernous sinus zoning in the diagnosis of pituitary adenoma invasiveness and the significance of endoscopic transnasal surgery for pituitary adenomas.Methods There were 75 cases with pituitary adenomas of Knosp grade 3-4(44 cases of Knosp grade 3 and 31 cases of Knosp grade 4)who were performed endoscopic transnasal surgery from July 2015 to June 2017 in our hospital.Based on coronal MRI of sellar region in patients with Knosp 3 pituitary adenomas,the ratio R of distance from the middle point of internal carotid artery(ICA)cavernous sinus segment to the upper part of anterior clinoid process segment and vertical distance from the furthest point of tumor invasion to the line was calculated and analyzed statistically.According to cavernous sinus zoning under endoscope and involvement of medial wall of cavernous sinus,patients with Knosp grade 3 pituitary adenomas were further divided into Knosp grade 3 A(invasive and non-invasive)and 3 B by invading different cavernous spaces.The total removal rate of tumor was reviewed by MRI in sellar region after operation.Results Among 75 cases,36 were classified as Knosp grade 3 A in 44 cases of Knosp grade 3 pituitary adenomas,including 12 cases of invasive pituitary adenomas(mainly involving posterior superior space of cavernous sinus and affecting oculomotor nerve)and 24 cases of non-invasive pituitary adenomas(the tumor pushed against the medial wall of cavernous sinus,presenting"pseudoinvasion").The ratio R of invasive pituitary adenomas was significantly smaller than non-invasive pituitary adenomas(1.28±0.18 vs.1.74±0.27;t=5.275,P=0.000).The Knosp grade 3 A was divided into 2 groups according to the median value of ratio R:≤1.59 group(17 cases)and>1.59 group(19 cases).The invasion rate of ratio R≤1.59 group was higher than that of>1.59 group(12/17 vs.0/19;Fisher’s exact probability,P=0.000).The total resection rate of 75 cases was 72%(54/75),among which the total resection rate of Knosp grade 3 was 84.09%(37/44),and rate of Knosp grade 4 was 54.84%(17/31).The average follow-up period was(14.84±5.66)months,and no one case relapsed.Conclusions The calculation of ratio R in preoperative coronal MRI helps to evaluate the invasion degree of Knosp grade 3 A pituitary adenomas.Combined with artificial division of cavernous sinus,it has guiding significance in endoscopic transnasal surgery for pituitary adenoma removal.