Toshida Hiroshi, Nguyen Doan H, Beuerman Roger W, Murakami Akira
Juntendo University School of Medicine, Hongo, Tokyo, Japan.
Invest Ophthalmol Vis Sci. 2007 Oct;48(10):4468-75. doi: 10.1167/iovs.06-1486.
To evaluate ocular surface status after interruption of preganglionic, parasympathetic neural control after surgical removal of the greater superficial petrosal nerve (GSPN).
New Zealand White rabbits underwent unilateral section and removal of a 5-mm portion of the GSPN by a route through the inner ear; no ocular or orbital tissue was involved. Before and 7 days after surgery, all animals underwent preliminary examination, including fluorescein staining, rose bengal instillation, blink rate, tear breakup time (BUT), tear flow, and impression cytology. Total tarsorrhaphy was carried out in four additional rabbits, and another four animals underwent unilateral sham procedures. The GSPN, pterygopalatine ganglion, lacrimal gland, and conjunctiva were evaluated by light and transmission electron microscopy (TEM).
GSPN sectioning resulted in significant changes of the ocular surface after 7 days: intense rose bengal staining of the conjunctiva, fluorescein staining of the cornea, increased blink rate (P < 0.05), decreased BUT (P < 0.005), decreased tear flow by 26% (P < 0.005), and decreased goblet cell density (P < 0.01). TEM revealed massive accumulation of secretory granules in lacrimal acinar cells. The changes were also seen after tarsorrhaphy. Neither the contralateral control nor the sham eyes were affected.
The effects of GSPN nerve section led to the rapid onset of a dry eye condition in the rabbits that continued for at least 1 week. The authors suggest that continuous neural drive of the pterygopalatine ganglion is necessary to maintain adequate tear flow and mucin secretion. It is likely the trigeminal system is the afferent origin of this continuous neural tone.
评估在手术切除岩浅大神经（GSPN）后，节前副交感神经控制中断后的眼表状况。
新西兰白兔通过内耳途径接受单侧切断并切除5毫米长的GSPN；未涉及眼或眼眶组织。在手术前和手术后7天，所有动物均接受初步检查，包括荧光素染色、孟加拉玫瑰红滴眼、眨眼频率、泪膜破裂时间（BUT）、泪液流量和印片细胞学检查。另外四只兔子进行了完全睑裂缝合，另有四只动物接受了单侧假手术。通过光镜和透射电子显微镜（TEM）对GSPN、翼腭神经节、泪腺和结膜进行评估。
切断GSPN后7天，眼表出现显著变化：结膜强烈的孟加拉玫瑰红染色、角膜荧光素染色、眨眼频率增加（P < 0.05）、BUT降低（P < 0.005）、泪液流量减少26%（P < 0.005）以及杯状细胞密度降低（P < 0.01）。TEM显示泪腺腺泡细胞中分泌颗粒大量积聚。睑裂缝合后也出现了这些变化。对侧对照眼和假手术眼均未受影响。
GSPN神经切断的影响导致兔子迅速出现干眼状况，且持续至少1周。作者认为翼腭神经节的持续神经驱动对于维持充足的泪液流量和黏蛋白分泌是必要的。三叉神经系统很可能是这种持续神经张力的传入起源。
