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Dissociated vertical deviation
Strabismus
Key Points
- •DVD is a bilateral, asymmetric, slow upward drift with abduction and excyclotorsion under cover - it is NOT a true hypertropia because the fellow eye does not show a corresponding hypodeviation (violates Hering's law)
- •Strongly associated with infantile esotropia (>50%), latent nystagmus, and IOOA - all reflect disrupted binocular cortical development in early life
- •The Bielschowsky darkening test is pathognomonic - ND filter over fixating eye causes the elevated dissociated eye to drift downward; this does not occur in true hypertropia
- •Superior rectus recession (6–8 mm, bilateral) with or without a Faden (posterior fixation) suture is the primary surgical approach; IO anteriorization is preferred when IOOA coexists
- •DVD is a lifelong condition that does not spontaneously resolve; surgical correction reduces amplitude but complete elimination is achieved in only 50–60% of cases
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Keep reading Dissociated vertical deviation
12 more sections are included with the Clinical plan.
- Definition
- Epidemiology
- Aetiology and causes
- Pathogenesis
- Classification
- Clinical features