Spontaneous Acute Proptosis During Phacoemulsification: Immediate Management Of A Rare Intraoperative Complication

This study aims to report and analyze a rare and unprecedented case of spontaneous acute proptosis occurring during phacoemulsification surgery in a patient without a confirmed diagnosis of Graves' disease. While intraoperative proptosis is most commonly associated with retrobulbar hemorrhage, this case highlights an alternative mechanism that remains poorly documented in the literature. By detailing the clinical presentation, intraoperative findings, and immediate management strategies, this report provides valuable insights into the potential anatomical and physiological contributors to this rare complication.Understanding intraoperative ocular emergencies and unexpected cataract surgery complications is imperative.

This case was conducted at IPEPO, a philanthropic organization established in 1990. IPEPO features advanced facilities and a specialized surgical center. The surgical intervention was carried out at IPEPO's surgical center in São Paulo. The surgical team included an anesthesiologist, an attending ophthalmologist, and an ophthalmology resident. Phacoemulsification was executed utilizing the Centurion Silver system.

A male patient with hypertension, diabetes, heart disease, high myopia, and an undiagnosed thyroid disorder under investigation was referred for cataract surgery.  Preoperative examination revealed visual acuity of counting fingers at 1 meter in the affected eye, mild binocular proptosis, unremarkable eyelids, a nuclear cataract graded as 4+, a posterior subcapsular cataract graded as 4+, and an anterior cortical cataract graded as 3+ (LOCS III). The Van Herick angle was classified as grade 4, intraocular pressure (IOP) was measured at 14 mmHg, and fundoscopy findings were consistent with a myopic fundus. 

During the first nucleus fracture, a sudden and rapid extrusion of the eye from the orbit occurred and was promptly documented by the anesthesiology team. The patient reported sudden pain, along with a sharp rise in intraocular pressure. Despite the proptosis, the anterior chamber remained deep and well-formed. As intraocular pressure continued to increase, the chamber deepened excessively, yet the integrity of the capsular bag remained intact. Given the imminent risk of optic nerve damage or expulsive complications, the surgical team promptly removed the lid speculum, facilitating spontaneous globe repositioning, accompanied by an audible click. Notably, neither mannitol administration nor pars plana vitrectomy was required. The procedure was subsequently completed without the use of the lid speculum, with ocular stability maintained and no further symptoms noted. 

This case illustrates an uncommon instance of intraoperative proptosis during phacoemulsification without a confirmed diagnosis of Graves' disease. While proptosis is typically associated with thyroid eye disease or retrobulbar hemorrhage, this case suggests the involvement of other, yet unexplained, anatomical or physiological factors. Prompt and effective management of this complication prevented vision-threatening outcomes, highlighting the importance of timely surgical intervention. Given the scarcity of similar reports in the literature, this case provides important contributions to ophthalmic surgery, emphasizing the need for heightened awareness of unusual intraoperative events and their potential systemic links.