Evaluating the extent of change in near point of convergence in traumatic brain injury: a systematic review and meta-analysis.

OBJECTIVE: Traumatic brain injury (TBI) causes significant impact on visual system. This study reports the impact of TBI on the near point of convergence (NPC) measure in individuals with mild TBI. METHODS: A systematic review and meta-analysis were conducted for studies that quantified NPC changes in mild TBI. The relevant studies were searched using search engines such as PubMed, EMBASE, Medline and Google Scholar. Thirty studies fulfilled the criteria for systematic review while twelve studies were included in the meta-analysis from 444 patients with mild TBI and 881 controls. RESULTS: This study showed a large and significant impact of head injury on the clinical measure of NPC in patients with mild TBI with a combined effect size of 0.98(95% CI: 0.67-1.29) and significantly moderate heterogeneity (Q(18) = 60.84,P = .001,I2 = 72.06%). Moderator analysis and subgroup analysis showed no difference in effect size with age and post-injury period. CONCLUSIONS: This study demonstrated that NPC is largely affected by the impact of TBI. Given the ease with which it can be measured and without the need of specialists and dedicated equipment, NPC measure might provide a supplementary measure of oculomotor function in addition to less sensitive and more subjective questionnaires and personal reports.