Unexpected Posterior Ischemic Optic Neuropathy After Uneventful Cataract Surgery: First Presentation Of Significant Carotid Stenosis

To report a case of posterior ischemic optic neuropathy (PION) occurring after uncomplicated cataract surgery, which led to the diagnosis of severe bilateral carotid artery stenosis (CAS), and to emphasize the importance of vascular evaluation in cases of unexplained postoperative vision loss.

Tertiary care ophthalmology department.

A 69-year-old male with pseudoexfoliation syndrome and nuclear cataract (BCVA 3/10 OD, 5/10 OS) underwent uncomplicated phacoemulsification in the right eye. Due to zonular instability, a sulcus intraocular lens was implanted. Early postoperative intraocular pressure elevation from retained viscoelastic was managed successfully. During follow-up, progressive visual decline occurred without identifiable anterior or posterior segment pathology. Visual field testing showed complete visual field loss in the operated eye. Suspecting posterior ischemic optic neuropathy, systemic evaluation including laboratory workup and carotid Doppler ultrasonography was performed.

Carotid imaging revealed severe bilateral carotid artery stenosis, with 90% obstruction of the right carotid artery and 80% obstruction of the left carotid artery. These findings confirmed the diagnosis of PION and established it as the first clinical manifestation of previously undiagnosed CAS.

PION after apparently uncomplicated cataract surgery may represent an early warning sign of significant carotid artery stenosis. Unexplained postoperative vision loss warrants prompt neuro-ophthalmic and vascular assessment. Early recognition of underlying carotid disease is crucial, as timely intervention may prevent further visual loss and potentially life-threatening cerebrovascular events.