Quantitative evaluation of extraocular muscles dimensions, orbital fat, and eyelid position in anophthalmic sockets following evisceration and primary orbital implant.

PURPOSE: To evaluate the dimensions of the extraocular recti muscles (EORM), orbital fat (OF), and eyelid position in anophthalmic sockets (AS).

METHODS

Twenty-nine individuals with unilateral acquired AS repaired with conical implants and external ocular prosthesis (G1) underwent orbital assessment by computed tomography (CT), and photo documentation of eyelid position. AS were compared to the contralateral normal side (G2) at baseline (before surgery - M1) and 180 days after surgery (M2). Measurements included the thickness and area of the EORM: levator complex (LC), inferior rectus (IR), medial rectus (MR), and lateral rectus (LR) - as well as the volume of EORM and OF. Statistical analyses were used to evaluate differences between groups and across time points (M1 and M2).

RESULTS

LC, MR, and IR thickness, MR area, and OF volume were significantly higher in G1, especially at M2. Upper and lower margin reflex distances, as well as both vertical and horizontal palpebral fissures, were reduced in G1M1 but improved after surgery (G1M2). Eyebrow - ciliary margin distance and the superior palpebral sulcus depth remained higher in G1 at both moments.

CONCLUSIONS

Structural changes and redistribution of EORM and OF in AS contribute to characteristic alterations in orbital contour and eyelid position, influencing both aesthetic and functional outcomes. Some modifications appear to precede surgery, reflecting the underlying pathology of blind eyes. Although reconstruction with implants and a customized external prosthesis improves overall symmetry, residual differences may persist. Longer longitudinal studies are warranted to clarify these mechanisms and optimize rehabilitation strategies to improve long-term outcomes.