Vergence and accommodation deficits subacutely and chronically in concussion recovery

Abstract

Purpose : Deficits in vergence and accommodation are commonly reported following concussion. We explored if the frequency and subtypes of vergence deficits (VD) and accommodation deficits (AD) vary between subacute (>15 days to 12 weeks) and chronic (> 12 weeks to < 1 year) phases of concussion recovery along with sex-based differences.

Methods : Retrospective cross-sectional study. Chart review of patients with concussion evaluated at Boston Children’s Hospital between August 2012 and March 2020. Inclusion criteria: 7-18 years; 20/30 vision or better in each eye; complete assessment of vergence and accommodation; no strabismus, amblyopia, or other ocular pathology. Results were compared to a non-concussed control group (n= 30; median age: 9.2, IQR: 8.1 -10.6 years) recruited and evaluated from April to October 2016. VD and AD were characterized based on clinical findings falling outside of the 95^th percentile of the control group. Chi-square and Fischer’s exact test (FET) were used to assess diagnosis and subtype differences.

Results : A total of 256/423 (61%) patients fit inclusion criteria with 115 evaluated in the subacute (median age: 15 IQR: 13.6 - 16 years; 60% females) and 141 in the chronic (median age: 15.4; IQR: 13.7 -16.8 years; 67% female) phases of concussion recovery. Frequency and subtype of VD and AD were not significantly different between subacute and chronic cohorts (45% vs 52% and 84% vs 83%, respectively). In the subacute phase, the frequency of AD was lower in females compared to males (65.3% vs 82.6%, χ2 = 4.15, p=0.04). In the chronic phase, frequency of AD was similar in both sexes (67% vs 75%), but there was a difference in subtype of AD (FET, p<0.001) with accommodative insufficiency in 56% vs. 23% (χ2 = 14.48, p<0.001), accommodative excess in 7.4% vs 15% (χ2 = 2.1, p=0.15) and accommodative dysfunction in 10.5% vs. 26.1% (χ2 = 5.69, p=0.017) females vs males, respectively. This difference is likely due to a trend towards higher failure rate with accommodation amplitude in females (64% vs 50%, FET p=0.07) and higher failure rate of accommodative facility in males (52% vs 25%; FET, p=0.002).

Conclusions : We found no difference in the frequency of VD or AD in the subacute and chronic phases of concussion recovery. In the chronic phase sex-based differences were noted in subtype of AD. Low accommodative amplitude drove AD in females but poor accommodative facility drove AD in males.

This is a 2021 ARVO Annual Meeting abstract.