Optic neuropathy diagnosis in the emergency room - retrospective observational study of the last 18 years.

Introduction: Optic neuropathies (ON), a broad spectrum of disorders of the optic nerve, are a frequent cause of visual loss, presenting either in isolation or associated to neurological or systemic disorders. They are often first evaluated in the Emergency Room (ER) and a rapid determination of the etiology is imperative for implementing timely and appropriate treatment. We aim to describe ER demographic data and clinical characteristics, as well as the performed imaging exams, of patients subsequently hospitalized and diagnosed with ON. Furthermore, we seek to explore the accuracy of ER discharge diagnosis and evaluate possible predictive factors that may influence it.

Methods: We retrospectively reviewed the medical records of 192 patients admitted to the ward of the Neurology Department of Centro Hospitalar Universitário São João (CHUSJ), with a discharge diagnosis of ON. Subsequently, we selected those admitted from the ER, with clinical, laboratory and imaging data, between January 2004 and December 2021.

Results: We included 171 patients. All participants were discharged from the ER and admitted in the ward with a main diagnostic suspicion of ON. Patients were stratified according to suspected etiology at the time of discharge: 99 inflammatory (57.9%), 38 ischemic (22.2%), 27 unspecified (15.8%) and 7 other (4.1%). By comparing with current follow-up diagnosis, 125 patients had an accurate ER diagnosis category (73.1%), 27 had an ON diagnosis of unspecified etiology that was defined only during follow-up (15.8%) and 19 had an inaccurate diagnosis category (11.1%). Diagnostic change was more common with ER ischemic diagnosis (21.1%) compared to inflammatory diagnosis (8.1%) (p = 0.034).

Conclusions: Our study reveals that most patients with ON can be accurately diagnosed in the ER through clinical history neurological and ophthalmological evaluation.