This document outlines the causes, categories, diagnostic approach, and management strategies for adult onset strabismus and diplopia. It discusses emergent causes such as pituitary apoplexy and aneurysmal CN III palsy. It categorizes causes as neurological, orbital/muscular, or neuromuscular junction disease. The diagnostic approach involves clinical examination, ancillary testing such as imaging and lab studies. Management options include patching, temporary prisms, or strabismus surgery versus chronic prism use.

1. Adult Onset Strabismus and Diplopia
Prem S Subramanian, MD, PhD
I. Emergent causes of diplopia
A. Pituitary apoplexy
B. Aneurysmal CN III palsy
C. CN VI palsy with papilledema
II. Categories of disease
A. Neurological
1. Supranuclear disorders
2. Nuclear/fascicular
3. Cranial nerve palsy
4. Phoria decompensation
B. Orbital/muscular
1. Thyroid eye disease
2. Orbital tumor
3. Infiltrative disease
4. Orbital pseudotumor
C. Neuromuscular junction disease
1. Myasthenia gravis
2. Eaton-Lambert myasthenia
3. Other
III. Diagnostic Approach
A. Clinical examination
1. Observation of head postures
2. Prism and cover testing
3. Alternative diplopia measurement techniques
B. Ancillary testing
1. Ice and rest testing
2. Forced duction testing
3. Prostigmin vs Tensilon testing
4. Orbital echography
5. Neuroimaging study- what to order, and when?
6. Lab studies
IV. Management
A. Patching vs. tape occlusion
B. Temporary (Fresnel) prism
C. Strabismus surgery vs chronic prism use