Anterior scleral thickness in acromegaly: a prospective multimeridional optical coherence tomography analysis

Acromegaly is a chronic endocrine disorder characterized by prolonged exposure to excess growth hormone (GH) and insulin-like growth factor-1 (IGF-1), leading to systemic connective tissue remodeling. Although corneal and choroidal structural changes have been extensively reported, scleral alterations remain poorly understood. This prospective case–control study aimed to quantitatively assess anterior scleral thickness (ST) across multiple meridians in patients with acromegaly compared with healthy controls using anterior segment optical coherence tomography (AS-OCT). Fifty-five eyes were examined 22 from patients with confirmed acromegaly and 33 from age- and sex-matched healthy controls. Baseline ocular characteristics, including axial length (optical biometry) and refractive status (manifest refraction; spherical equivalent = sphere + ½ cylinder), were recorded for all participants.Scleral thickness was measured at eight meridians (inferior, superior, temporal, nasal, inferotemporal, inferonasal, superotemporal, superonasal) using standardized AS-OCT imaging. Between-group differences were analyzed using the Mann–Whitney U test, and effect sizes were expressed as Cohen’s d. Across all meridians, acromegaly patients demonstrated significantly thicker sclera compared with controls: inferior (673.2 ± 51.6 μm vs. 636.9 ± 33.1 μm, p = 0.024, d = 0.87), superior (650.7 ± 31.3 μm vs. 613.0 ± 31.3 μm, p = 5.6 × 10⁻⁵, d = 1.20), temporal (674.2 ± 35.8 μm vs. 620.6 ± 42.4 μm, p = 5.0 × 10⁻⁶, d = 1.34), and nasal (694.1 ± 53.5 μm vs. 637.2 ± 59.5 μm, p = 0.0016, d = 0.99). Oblique meridians showed parallel trends. Axial length was higher in the acromegaly group, while spherical equivalent did not differ significantly between groups. Anterior sclera is significantly thickened in acromegaly, consistent with GH/IGF-1–driven extracellular matrix expansion. These findings extend the ocular phenotype of acromegaly beyond corneal and choroidal changes, highlighting the need to consider scleral biomechanics in ocular and systemic disease evaluation.