Grading system for retinal hemorrhages in abusive head trauma: clinical description and reliability study

There is currently no universally accepted grading system for describing retinal hemorrhages (RH) in abusive head trauma (AHT). The purpose of this study was to devise and evaluate a novel grading system and descriptive nomenclature for RH in AHT for clinical and research purposes.

A traumatic hemorrhagic retinopathy (THR) grading system was developed for assessing and quantitatively analyzing retinal findings in abusive head trauma. The criteria for the THR grade included the extent, spread, and morphology of RH. Extent was classified as region 1 (posterior pole) or region 2 (peripheral). Spread, based on number of retinal hemorrhages, was classified as mild (10 or fewer RH), moderate (more than 10 RH) and severe (more than half of involved regions covered by RH). Morphology was classified by its intraretinal or extraretinal involvement. Two independent graders calculated the THR grade from RetCam images of 38 eyes of 19 patients <3 years of age with retinal hemorrhages associated with head injury. Grading was performed on two separate occasions. Intra- and interobserver reliability was assessed with Spearman correlation coefficient (r) and intraclass correlation coefficient (ICC).

There was a high level of intraobserver agreement across both assessments (97% agreement [Spearman r = 0.997; P < 0.0001] and 100% agreement [Spearman r = 1.0; P < 0.0000]). Intraclass correlation (ICC, 0.995; 95% CI, 0.991-0.997; P < 0.0001) confirmed a very high level of agreement overall.

The traumatic hemorrhagic retinopathy grading system demonstrated excellent intraobserver and interobserver reliability. The nomenclature is easily understood and may be useful in medical records and medicolegal reports.