Detailed anatomy of the capsulopalpebral fascia.

This study was designed to elucidate the detailed anatomy of the capsulopalpebral fascia (CPF) and capsulopalpebral head (CPH), and their relationships to the inferior rectus muscle (IRM). In this cohort study, 40 eyes from 20 cadavers were observed macroscopically. Dissection was carried out from the CPF origin to its insertion, and the CPF origin pattern was photographed in each specimen. The width, length, and tensile strength of the CPF were measured. The CPF originated 25.07 ± 1.07 mm laterally and 24.86 ± 1.10 mm medially from the origin of the IRM and extended to the lower border of the inferior oblique muscle, and it firmly adhered to the IRM surface and formed into the CPH. The CPH was 4.31 ± 0.86 mm laterally and 6.18 ± 1.94 mm medially in length and 7.47 ± 0.81 mm in width. The CPF originated from the total width or 3/4 temporal part of the IRM in 32 (80%) of 40 faces. There was asymmetry in the pattern of the CPF origin between the left and right eyes in 4 of 20 paired specimens (20%). The tensile strength of the posterior layer was 19.12 ± 11.22 N, which was significantly higher than that of the anterior layer (8.59 ± 3.88 N) (P = 0.001). This study provided a good understanding of the CPF structures conducive to performing IRM surgery.