Reticular fiber distribution in sclera: Key to understanding pathologic myopia and posterior staphylomas

To characterize the distribution of reticular fibers in the human sclera and explore their potential role in the pathogenesis of pathologic myopia and posterior staphyloma.

Central sagittal sections of 13 globes (6 right eyes and 7 left eyes) were obtained from 12 East Asian cadavers aged 38-94 years (mean age: 74.9 years). Three scleral regions were examined: the pars plana, 3:00-3:30 clock-hour position, and 5:00-5:30 clock-hour position. Specimens were fixed in 10% formalin and stained with silver nitrate. ImageJ software was used for image processing and quantification of fiber density.

Reticular fiber density exhibited considerable inter- and intraindividual variability. The average densities at the pars plana, 3:00-3:30, and 5:00-5:30 were 31.07%, 26.10%, and 22.70%, respectively. Density ranges were 23.46%-58.51% (pars plana), 19.18%-43.07% (3:00-3:30), and 13.48%-50.95% (5:00-5:30). In 10 eyes, the pars plana showed the highest density, followed by 3:00-3:30 and then 5:00-5:30. Two eyes had the lowest density at 3:00-3:30, while one eye exhibited the highest density in this region.

Reticular fiber density in the sclera exhibits considerable interindividual variability. Our findings suggest that regions of structural vulnerability within the sclera may extend beyond the posterior pole, potentially offering new insights into the pathogenesis of posterior staphyloma. A reduction in reticular fiber density may be implicated in the progression of pathologic myopia and the development of posterior staphylomas, although further investigation is warranted to substantiate this association.