Abstract Number: Esoc2026ys278 Point-of-Care Ultrasound for the Diagnostic Evaluation of Acute Visual Loss in the Emergency Department: A Protocol Proposal

Background and aims Acute visual loss is a time-critical emergency in which delayed etiologic diagnosis may increase the risk of permanent disability and postpone time-dependent therapies. In the emergency department, comprehensive diagnostic work-up may be limited by access to ophthalmologic assessment, vascular imaging, and advanced neuroimaging. This study aims to evaluate the accuracy and feasibility of a standardized multimodal ultrasound (US) protocol as a bedside screening tool for AVL. Methods This is a prospective, observational diagnostic accuracy study. The proposed protocol integrates: 1) Ocular US for optic nerve diameter (OND) and optic nerve sheath diameter (ONSD); 2) Central Retinal Artery (CRA) Doppler; 3) Temporal artery Doppler (halo sign); 4) Carotid Doppler (velocity screening); and 5) Transcranial Doppler (TCD) of the posterior cerebral artery including neurovascular coupling tests. The study consists of two phases: first, neurology and emergency medicine residents undergo standardized training (target: ten supervised exams). Second, trainees perform the protocol on patients presenting with AVL. Findings will be compared against the "gold standard" clinical and neuroimaging diagnosis. Reliability and inter-observer agreement will be assessed. Results The study is currently in the initial phase; the protocol was finalized. Preliminary assessments suggest the protocol is reproducible and can be completed within 10–15 minutes. Training and ethics submission in progress. We expect the protocol provides a valuable triage tool for the ED. Conflict of interest Nothing to disclose.