Infographic. Keep an eye on vision after concussion—screening tool and procedure for the two most common concussion-related vision disorders: convergence insufficiency and accommodative insufficiency

Visual dysfunction is common after a concussion. A prospective study reported that 79/113 (70%) of adolescents had concussion-related vision problems. 1 Accommodative and convergence insufficiency were the most common.1 Both can be easily screened for, as recommended by best practices in national and international concussion guidelines.2 3 Convergence insufficiency is screened for by measuring the near point of convergence (NPC), with a result of >6 cm considered abnormal.4 Accommodative insufficiency can be detected by measuring the amplitude of accommodation (AA), for which age-dependent norms are available; see figure 1.5 The American Academy of Pediatrics has suggested that a randomised clinical trial (RCT) is needed to assess the effectiveness of therapeutic interventions for concussion-related vision dysfunction.2 The CONCUSS RCT addresses this need by answering (1) the effectiveness of therapy, (2) dosing differences and (3) impact of treatment delay.6 The accompanying video and Figure 1 demonstrate how to measure and interpret the NPC and AA. The following are the best practices when measuring NPC and AA.