Rev Bras Oftalmol.2026;85:e0041
Shamrock sign: a novel indicator of myopia in nuclear cataracts
DOI: 10.37039/1982.8551.20260041
ABSTRACT
This case series presents the shamrock sign, a novel aberrometry pattern characterized by trefoil and coma, as a potential diagnostic marker for nuclear cataracts associated with myopic shift. This study highlights its clinical relevance and contribution to early detection and management. The primary diagnosis was nuclear cataracts inducing myopic shift. All patients underwent phacoemulsification with intraocular lens implantation. Postoperatively, all cases showed marked reductions in higher-order aberrations, including spherical aberration and trefoil, with complete resolution of the shamrock sign. Visual acuity improved significantly, achieving 20/20 in all patients, underscoring the efficacy of surgery in addressing both visual impairment and aberrometry patterns associated with nuclear cataracts. The shamrock sign, identified via aberrometry, may be a reliable diagnostic marker for nuclear cataracts associated with myopia. Its post-surgical resolution underscores its value in guiding clinical decisions and improving diagnostic precision in cataract management.
