Influence of surgical approach for decompression on lower eyelid position in thyroid eye disease.

Purpose: Orbital decompression for thyroid eye disease (TED) has been noted to improve lower lid retraction by 0.5-1 mm. We hypothesize that orbital decompression via transconjunctival approach may lead to increased reduction in marginal reflex distance 2 (MRD2) as it involves division of the lower lid retractors. The purpose of this study is to evaluate relative changes in lower lid position for patients undergoing lateral and transconjunctival orbital decompression, respectively.Methods: In this cross-sectional study, all TED patients managed with lateral or transconjunctival orbital decompression for a 3-year period were screened for inclusion. Photographs taken in the primary position preoperatively and three months postoperatively were utilized to evaluate the MRD2 from each patient. Measurements were made utilizing NIH ImageJ software standardized to a corneal diameter. Hertel measurements of proptosis were obtained pre and postoperatively. The primary outcome measure was MRD2 in operative eyes.Results: A total of 131 (86 patients) operative eyes were included in the sample. Mean change MRD2 was not significantly different between the surgical groups (p = 0.07). In multivariate modeling, mean change in MRD2 was significantly associated with change in exophthalmometry, independent of surgical approach.Conclusions: The association between decrease in Hertel measurement and decrease in MRD2 is consistent with the existing literature on the topic. It appears that transconjunctival division of the lower eyelid retractors provides no additional benefit in reducing lower lid retraction relative to change in proptosis.

Relationship between ocular dominance and brow position in patients with blepharoptosis.

PURPOSE: This study aims to determine if ocular dominance plays a role in predicting compensatory eyebrow elevation in cases of ptosis. METHODS: This retrospective observational cohort study screened all individuals presenting to two tertiary oculoplastics practices with complaints of ptosis for entry. Primary position photographs were obtained. Ocular dominance was assessed via a modified Porta test. Ptosis was defined in bilateral cases as marginal reflex distance of <2.5 mm in both eyes and in unilateral cases as either an MRD1 < 2.5 mm or MRD1 of >1 mm lower on one side. Asymmetry in brow height was defined as a difference of >1 mm. Chi square and t-tests were performed. RESULTS: Sixty-eight patients from the both tertiary practices met inclusion criteria (37 male, 31 female). Concordance between the higher brow and the dominant side was 50.0% (n = 22, p > 0.05). Mean brow height on the dominant side (15.5 mm) was not statistically different than brow height on the non-dominant side (15.3 mm, p > 0.05). The concordance between the higher brow and the lower MRD1 eyelid was not significant (45.5%, n = 20, p > 0.05). The difference in mean brow height between the lower and higher MRD1 eyes was not significantly different (-0.11 mm; p > 0.05). This also held true when restricted to unilateral cases (0.28; p > 0.05). CONCLUSIONS: Although asymmetric brow elevation can be noted in patients with ptosis, ocular dominance does not appear to be concordant with this asymmetry. Additionally, brow height does not appear to be concordant with MRD1 in cases of ptosis.