Prediction of inflicted brain injury in infants and children using retinal imaging.

BACKGROUND: Retinal hemorrhages (RHs) occur in inflicted traumatic brain injury (ITBI), accidental traumatic brain injury (ATBI), and some medical conditions, although the reported number, distribution, type, and frequency vary greatly between these different etiologies. We hypothesize that these RH characteristics reliably help to distinguish ITBI from ATBI and nontraumatic etiologies. METHODS: A 6-year prospective observational study using wide-field retinal imaging (RetCam) was conducted within 24 hours of admission to PICU, on serially recruited children with traumatic and nontraumatic encephalopathies. "Definite" and "probable" ITBI cases were confirmed by multiagency child protection case conferences. Image analysis used digital color and grayscale images for retinal "zoning" and "layering" of hemorrhages. RESULTS: Significant differences were found between the mean numbers of hemorrhages in ATBI/ITBI, and ITBI/nontraumatic etiologies for the 3 retinal zones (range, P = .003-.009) and for the dot-blot hemorrhages (range P = .001-.002). The mean numbers of RHs per ITBI patient in the peripapillary, macula, and peripheral zones were 14, 28, and 31 respectively. RHs in ATBI were near the optic disc and more superficial than in ITBI, where hemorrhages involved deeper layers (range, P = .003-.039) and were more peripheral (P = .03). The positive predictive value for ITBI in children <3 years with >25 dot-blot (intraretinal) hemorrhages was 93%. CONCLUSIONS: This prospective study, which included all potential causes of RHs, with objective retinal methodology, has confirmed that a young age and a high dot-blot count are strong predictors of ITBI. This high predictive value may support medicolegal deliberations.