Neuro-Ophthalmic
Decompensated Phoria
Also known as: decompensated phoria, decompensated heterophoria, intermittent diplopia, fatigue diplopia, exophoria, esophoria, vergence insufficiency, convergence insufficiency
Filed as: Routine
Source-cited from the record's own evidence list. Clinical content programme led by Dr Ankit Mathur, PhD, Grad Cert Ocu Thera, B.S. Optom. How the clinical content is governed
Clinical decision support only
Overview
A latent deviation that intermittently breaks down, giving double vision after sustained reading or screen work and toward the end of the day rather than on waking. Cover testing reveals the phoria and vergence testing shows reserves too small to hold it, with a full range of eye movement throughout. The absence of any motility limitation is what separates it from an acquired palsy.
Recognition
Symptoms: what patients report
- Intermittent horizontal diplopia — particularly after prolonged reading, screen use, or when fatigued.
- Symptoms worsen toward the end of the day or after sustained near work.
- Diplopia resolves with rest, closing one eye, or brief monocular occlusion.
- Headache associated with eye strain or near work.
- Occasionally, reduced reading fluency or difficulty maintaining single binocular vision.
- No pain on eye movement.
Signs: what the examination shows
- Heterophoria on cover test — exophoria (outward deviation) or esophoria (inward deviation) revealed when fusion is disrupted.
- Poor fusional reserves on near or distance vergence testing — the phoria exceeds the ability to compensate.
- No limitation of ocular movement — full range of movement in all directions.
- Normal pupils.
- Normal optic discs.
- Symptoms reproduced by dissociation (prism bar cover test, Worth 4-dot, or prolonged cover).
What OptoGuide™ covers for decompensated phoria
- Pattern reasoning: what this combination of findings points to, and its differentiators
- Don't-miss risks and escalation triggers
- Management tiers with linked Australian therapeutics
- Referral urgency, specialty, and letter drafting
Sources
Standard texts: Kanski's Clinical Ophthalmology: A Systematic Approach, Oxford Handbook of Ophthalmology, Oxford American Handbook of Ophthalmology, Signs in Ophthalmology: Causes & Differential Diagnosis.