Diplopia in the Younger Adult (≤65 Years Old) Compared With Older Adult (>65 Years Old) Population-Presentation, Progression, and Outcome

Background: Despite the impact of new-onset diplopia on the quality of life, there are few studies concerning new-onset diplopia in seniors. This study aimed to describe the epidemiology, etiology, prognosis, and outcome of different treatments in the older adults compared with younger adult patients presenting with new-onset binocular diplopia. Methods: A retrospective chart review of patients ≥18 YO with new-onset binocular diplopia presenting between 2010 and 2021. Data collected included age at presentation, gender, duration of time since diplopia onset, imaging results, known trigger, etiology, treatment, and follow-up. Results: Two hundred ten patients were included. Of them, 75 patients were ≤65 YO (35.7%, the "younger adult group") and 135 > 65 YO (64.3%, the "older adults group"). The common etiology in both groups was neurogenic (54.7% ≤ 65 vs 62.2% >65, P = 0.29). Cranial nerve palsies were more commonly microvascular in the older adults (96.0% vs 74.1%, P = 0.005), whereas tumor-related cranial nerve palsies were more frequent in younger adults (14.81% vs 2.04%, P = 0.03). A restrictive etiology was observed in 20% of younger adult compared with 11.1% of older adults group ( P = 0.08). Sagging eye syndrome (SES) was the second most common etiology in the older adults group at 11.9%, compared with 1.3% in the younger adult group ( P = 0.01). Decompensated phoria/tropia appeared in 16% of younger adult group compared with 11.9% of older adults ( P = 0.4), with an obvious trigger (mostly cataract surgery) in the latter (80% older adults vs 20% younger adults, P = 0.019). Positive imaging findings were found in 46.7% of patients ≤65 compared with 25.3% of >65 ( P = 0.01) and complete spontaneous resolution of diplopia was noted in 32.1% of the older adults compared with 11.8% of younger adults ( P = 0.003). Conclusions: Neurogenic diplopia was the most common etiology for both groups, but is more prominent in the older adults. Noticeable findings in the older adults were SES diagnosis, identification of triggers for impaired fusion/diplopia, and a paucity of positive findings in imaging results. It is important to know these differences not only for managing seniors better, but also to minimize symptoms of binocular diplopia after lens-related procedures.