Novel handheld device allows point-of-care retinal assessment in kids

The handheld RETeval electroretinogram (ERG) device can make assessing retinal function in children easier relative to the traditional ERG, according to a recent study.

“It should be stressed that the RETeval cannot replace full visual electrodiagnostic assessment where other tests such as visual evoked potentials, pattern ERGs and electro-oculograms may be necessary to build a clinical picture,” the researchers said.

Forty-four healthy adults (mean age 39 years) and 37 young patients (mean age 5 years) participated in the present study. Retinal assessments were conducted with both the RETeval device and the standard Grass photic stimulator. Reference ranges were determined from adult measurements; paediatric results were deemed normal or abnormal based on the adult references and the overall ERG picture, as judged by two specialists.

After the procedure, participants were also interviewed regarding their views, compliance, general feedback, and preferred mode of retinal assessment.

In the healthy adults, the RETeval device and the standard method of measurement shared poor agreement, showing discrepancies in the interclass coefficients for amplitude and peak time. Bland-Altman plots confirmed these findings such that the one-way t-test revealed significant differences between the two systems across all measurements. [Eye 2021;35:2180-2189]

However, in children, RETeval had a high degree of diagnostic agreement with the standard Grass system. Cohen’s Kappa analysis revealed that both methods had comparable capabilities of detecting normal and abnormal ERGs (k, 0.80). The RETeval device demonstrated relative sensitivity and specificity values of 1.0 and 0.91, respectively.

Notably, the RETeval system was able to correctly identify all patients who had been identified as having abnormal ERG by the standard photic system.

Adult participants preferred the standard system to the RETeval device (67 percent vs 30 percent); 3 percent remained indifferent to the method of measurement. Assessments using the RETeval system took 5–15 minutes, while the standard photic simulator only required 3–10 minutes.

Of the 37 paediatric patients, three dropped out due to poor compliance to the RETeval device process, leading to incomplete readings.

“This study demonstrates the possible use of the RETeval system as a point-of-care triaging tool by healthcare professionals not specialized in electrodiagnostics,” the researchers said. “There are several patient groups that would benefit from this type of testing to identify normal or abnormal retinal function prior to a full visual electrodiagnostic referral.”

In particular, this device would benefit young patients with unexplained myopia, as well as those with rare or possibly genetic conditions, and with corneal opacities or cataract.

“The RETeval system produced five false positives across the normal and patient subjects, which the standard system demonstrated as being normal. However, the RETeval device did not produce any false negatives. This highlights the need for further testing of abnormal patients,” the researchers said.