Lamina cribrosa and peripapillary scleral histomorphometry in myopic and non myopic glaucomatous chinese eyes

Purpose To study the glaucomatous optic nerve head in Chinese eyes. Methods The histomorphometric investigation included a Normal group (non-highly myopic eyes) of 40 human globes enucleated due to a malignant choroidal melanoma, a Glaucomatous group (non-highly myopic eyes) of 55 eyes enucleated due to painful secondary angle-closure glaucoma, and a Highly Myopic Glaucomatous group of 26 glaucomatous globes with an axial length >26.5 mm. Anterior-posterior histological sections through the pupil and the optic disc were morphometrically evaluated and compared. Results The lamina cribrosa was significantly (P<0.001) thicker in the Normal group than in the Glaucomatous group, in which it was significantly (P<0.001) thicker than in the Highly Myopic Glaucomatous group. The lamina cribrosa thickness decreased significantly (P<0.001) with increasing axial length and presence of glaucoma (p<0.001). The peripapillary scleral thickness close to the optic nerve scleral canal and just outside of the optic nerve meninges decreased significantly with increasing axial length (P=0.04 and P=0.02, respectively). The peripapillary scleral thickness did not vary significantly between the Glaucomatous group and the Normal Group. The distance between the intraocular space and cerebrospinal fluid space was (p<0.001) shorter in the two glaucomatous groups than in the Normal group. Conclusion Lamina cribrosa thickness and peripapillary sclera thickness decreased significantly with axial length, in addition to a glaucoma-related thinning of the lamina cribrosa. Within non-highly myopic eyes, the peripapillary sclera thickness did not vary significantly between glaucomatous eyes and normal eyes.