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Characteristics of two subtypes of nonacute acquired comitant esotropia with distance diplopia
Kathleen Eng1, Yoon-Hee Chang1, David Zurakowski2
1Department of Ophthalmology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts.
Purpose:
To determine demographic and sensorimotor characteristics of patients with nonacute acquired comitant esotropia with distance diplopia (NACEDD).
Methods:
History, demographic, and sensorimotor characteristics of all patients ≥10 years of age presenting with esotropia and gradual-onset distance diplopia at Boston Children's Hospital (2017-2022) were collected. Definition of NACEDD required absence of inflammatory, autoimmune, mechanical, or neurologic causes of strabismus. Those with NACEDD were subdivided into patients with divergence insufficiency esotropia, defined as esotropia at near at least 25% less than that at distance (type 1), and all others (type 2).
Results:
A total of 249 patients met criteria for NACEDD: 171 type 1 and 78 type 2. Type 1 patients were older (60.3 ± 19.3 years vs 44.5 ± 20.7 years [P < 0.001]) and had a higher rate of sagging eye syndrome (42.1% vs 15.4% [P < 0.001]). Both subtypes were predominantly female (67.7% and 75.6% [P = 0.154]) and myopic (-3.4 ± 4.3 D vs -4.0 ± 3.1 D [P = 0.301]). Mean esotropia at distance was similar for type 1 and type 2 (16.2Δ ± 8.9Δ vs 17.7Δ ± 11.2Δ [P = 0.262]) but smaller at near for type 1 compared with type 2 (8.1Δ ± 7.9Δ vs 19.4Δ ± 12.8Δ [P < 0.001]).
Conclusions:
Patients with both subtypes of NACEDD were predominantly female and myopic and in spite of distinctive sensorimotor characteristics, were rarely diplopic at near. The prevalence of divergence insufficiency esotropia (type 1 NACEDD) has risen over prior decades. The increase in the disease burden of myopia may result in an increase in type 2 NACEDD as well.
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