Prevalence and Clinical Significance of Incidental Neuroimaging Findings in Neuro-Ophthalmology: A Retrospective Analysis of 5,000 Cases.

Abstract

Background: Patients referred to ophthalmology and neuro-ophthalmology clinics often present with complex neurological and visual symptoms, such as headaches, double vision, and vision loss, requiring thorough history, comprehensive examinations, and neuroimaging to identify the underlying cause. While advances in neuroimaging have improved diagnostic accuracy, they have also introduced challenges with incidental findings and unexpected abnormalities. This study aimed to determine the prevalence, spectrum, and clinical relevance of incidental findings in neuro-ophthalmology patients evaluated at an academic center.

Methods: A retrospective, observational cohort study included 5,000 patients (59% women, 41% men; mean age 53.7 years) who underwent neuroimaging (MRI and CT) for neuro-ophthalmic symptoms at an academic neuro-ophthalmology clinic between July 2008 and June 2024. Details of imaging type, region scanned, and reason for imaging were recorded from electronic medical records. Incidental findings were defined as abnormalities unrelated to the original reason for imaging and categorized into 4 follow-up categories (none, routine, urgent, and emergency). Imaging reports were independently reviewed and categorized by an ophthalmologist and a neuro-ophthalmologist. Descriptive statistics were used to assess the prevalence of incidental findings and their clinical significance. Chi-square tests and analysis of variance were applied to assess associations between imaging modalities, age, and the presence of incidental findings.

Results: Incidental findings were present in 31% (n = 1,532) of patients; 20.6% required no follow-up, 9.6% required routine follow-up, 0.34% required urgent follow-up, and 0.1% required emergency follow-up. The most common incidental findings were microangiopathic changes (14.2%), sinus changes (6.96%), and brain atrophy (3.26%). MRI showed a higher prevalence of incidental findings than CT (31.8% vs 25.1%, P < 0.05). There was no difference in incidental findings between 1.5T vs 3T MRI. Age was significantly associated with certain findings, such as microangiopathy and brain atrophy. The most common findings by follow-up category were microangiopathic changes (no follow-up), meningiomas (routine follow-up), suspected neoplasms (urgent), and suspected metastasis (emergency).

Conclusions: Incidental findings are common in neuro-ophthalmology imaging, with the majority requiring no or routine follow-up. However, a small percentage (0.44%) of cases required urgent or emergency attention, underscoring the need for careful evaluation and management protocols. These findings emphasize the importance of developing guidelines to manage incidentalomas in neuro-ophthalmology, particularly for older patients and those undergoing MRI.