Incidence and Pattern of Neuro-Ophthalmological Disorders Presenting to Vitreoretinal Clinics in Bhutan: A 3-Year National Study

Abstract

Purpose

To inform national health policy, we quantified the pattern of neuro-ophthalmological disorders (NODs) presenting to the national vitreoretinal clinics in Bhutan.

Study Design

Retrospective cross-sectional study.

Methods

We reviewed all new NODs patients over three years. Demographic data, presenting complaints, treatment history, systemic diseases, diagnostic procedures, and diagnoses were quantified. Logistic regression examined the odds of factors linked to more common NODs.

Results

Of 226 patients, the majority were males (54.0%), farmers (60.2%), and urbanites (55.8%). Loss of vision was the most common presenting complaint (57.9%), followed by head or orbital trauma (19.5%). The best corrected visual acuity (BCVA) of 216 eyes (47.8%) was ≤6/60. Hypertension was the most common systemic disease (16.4%), followed by diabetes (3.5%), and intracranial space-occupying lesions (3.5%). Neuroimaging (37.6%) was the most common diagnostic test performed, followed by visual field testings (VFTs) (22.9%). With a NOD incidence of 7.8% p.a. (226/2913), optic atrophy (OA) was diagnosed in 134 patients (59.3%). Other common NODs were optic neuritis (15.5%), papilloedema (9.3%), and traumatic optic neuropathy (8.4%). Female gender increased the odds for glaucomatous OA by 2.65× (p = 0.044), and age by 1.09× per year (p < 0.001). Being female increased the odds of optic neuritis by 2.57× (p = 0.03).

Conclusion

Over half of the NODs were OA, which could be curable with timely treatment. Improved treatment of glaucoma and non-communicable diseases would reduce the risk of NODs-induced visual loss in Bhutan. The need for improved neuro-ophthalmological assessment and a coordinated multidisciplinary approach to NODs are the highest priorities.

Keywords:

• Bhutan eye diseases
• neuro-ophthalmological disorders
• optic atrophy
• optic neuritis
• papilloedema

Disclosure

BBR reports scholarship provided by the Australian National University that supported the study. JPvK and TM report grants from the MRFF Biotechnology Bridge (BTB) Program – research grant number: BTBR100196, during the conduct of the study; grants from Konan Medical USA, outside the submitted work; In addition, they have a patent application (P0040304AU) on novel analysis methods for mfPOP/OFA pending to Konan Medical USA. TM owns shares from EyeCo Pty Ltd. The authors report no other conflicts of interest in this work.

Additional information

Funding

This is an Australian Government funding agency awarded to the Australian National University. This agency supplied 50% of the funding for this grant. As required by the grant the other 50% was matched funding 25% from our university (the Australian National University) and 25% from a potential commercial partner, which for this grant was Konan Medical USA.