Abstract
Background:
Vestibular and ocular motor deficits have been recognized as a key marker of the pathophysiology consistent with the diagnosis of concussion (Grady, 2010). Previous studies have been performed detailing the validity and clinical benefit of vestibular and ocular motor assessments (Corwin et al., 2015; Mucha et al., 2014). Recent guidelines and position statements have started recommending the use of vestibular and ocular motor assessment for pediatric patients (Matuszak et al., 2016), the most recent consensus statement recommending vestibular and ocular motor assessment by all practitioners within acute concussion settings (McCrory et al., 2017). Unfortunately, very little data exists with respect to vestibular and ocular motor performance in concussion patients between 8-12 years of age. The current study included a standardized administration of the Vestibular Ocular Motor Screening (VOMS) and the King-Devick Test (KD) in a sample of patients diagnosed with concussion and evaluated in an outpatient concussion clinic within 7 days of their initial date of injury. This study intended to evaluate performance on the VOMS and KD in an injured sample of patients 8-12 years of age.
Methods:
Pediatric patients diagnosed with concussion (n = 45) presenting to an outpatient concussion clinic within 7 days from their initial date of injury were administered a standardized version of the VOMS and KD. Patients were administered the VOMS and KD by certified athletic trainers educated and trained on administration. The VOMS consists of nine measures and was validated by the University of Pittsburgh (Mucha et al., 2014) as a symptom provocation measure with a symptom rating of 0-10 with convergence measured in centimeters, and scores of 6 cm or greater being indicative of abnormal. The KD is an ocular motor performance measure and has previously demonstrated reliability, sensitivity and specificity with respect to concussion diagnosis (Hecimovich et al., 2018). Demographic, acute injury, and baseline values were summarized using descriptive statistics. Point estimates and 95% confidence intervals were calculated for all end points. Pearson correlations were calculated based numerical values from the VOMS and KD data.
Results:
The total sample consisted of 14 females and 31 males, with a mean age of 10.6 + 1.4 years. 20% of the subjects (n = 9) reported a prior history of concussion with a total of 17 previous concussions reported. 13.3% of the sample (n = 6) reported a history of migraine and 4.4% (n = 2) reported a history of psychiatric diagnosis. Acute self-reported injury data based on signs and symptom markers were calculated including; dizziness (66.6%, n = 30), headache (82.2%, n = 37), vision problems (42.2%, n = 19), amnesia (35.5%, n = 16), and loss of consciousness (22.2%, n = 10). Descriptive statistics for baseline VOMS symptoms were recorded; headache (mean = 3.2 + 2.7, CI = 2.8-3.6), dizziness (mean = 1.3 + 1.7, CI = 1.1 -1.5) nausea (mean = 0.7 + 1.6, CI = 0.5-0.9), and fogginess (mean = 1.1 + 2.0, CI = 0.8 -1.4). VOMS convergence in centimeters across trials; T1 (mean = 5.1 + 5.2, CI = 4.6-5.9), T2 (mean = 6.2 + 5.8, CI = 5.3-7.1), and T3 (mean = 7.1 + 6.9, CI = 6.1-8.1). KD time in seconds; card 1 (mean = 22.4 + 9.5, CI = 21-23.8), card 2 (mean = 23.1 + 9.5, CI = 21.7-24.5), card 3 (mean = 27.2 + 9.3, CI = 25.8-28.6), and total (mean = 72.8 + 27.3, CI = 68.7-76.9). Pearson correlations revealed strong correlations across VOMS symptoms; headache (r = 0.89-0.99), dizziness (r = 0.78-0.98), nausea (r = 0.88-0.98), and fogginess (r = 0.89-0.98). Moderate correlations between KD time and convergence distance were observed; KD card 1 (convergence T1, r = 0.61, convergence T2, r = 0.58, convergence T3, r = 0.49), KD card 2 (convergence T1, r = 0.62, convergence T2, r = 0.58, convergence T3, r = 0.48), and KD total time (convergence T1, r = 0.59, convergence T2, r = 0.54, convergence T3, r = 0.46).
Conclusion:
To the best knowledge of the authors involved, this study is the first of its kind to explore the performance on the VOMS and KD in a sample of acutely injured (< 7 days) 8-12-year-old patients diagnosed with concussion. Several notable findings were observed. Headache was the most predominant symptom reported during VOMS administration and remained significantly higher than the other symptoms of dizziness, nausea, and fogginess. This finding may be the byproduct of increased difficulty in symptom description between the ages of 8-12. Further, correlations within symptoms were strong suggesting throughout VOMS administration symptoms remain relatively stable. Lastly, moderate relationships were noted between convergence on the VOMS and KD time scores. This is likely a result of both measures addressing ocular motor functioning but differing based on data medium (centimeters versus seconds). The current study was limited based on sample size and further data is necessary to draw larger conclusions based on 8-12-year-old injured VOMS and KD performance.