Easee Shows Promise for Post-Cataract Surgery

An online visual acuity test enables the measurement of postoperative visual acuity in cataract patients with an accuracy akin to those achieved with Snellen and ETDRS charts performed in a clinical setting, according to the results of a study presented by Joukje Wanten MD. Called Easee, the web-based tool uses smartphone and computer screens to take measurements.

The single-centre prospective hospital-based validation study, conducted in the University Eye Clinic Maastricht, the Netherlands, involved 75 eyes of 46 patients who had undergone cataract surgery. The participants included 22 women and 24 men with a mean age of 62.8 years. All had undergone uncorrected (UDVA) and corrected distance visual acuity (CDVA) assessments at their fourweek postoperative check-up using Snellen charts.

After providing informed consent, the participants performed UDVA and CDVA testing using the web-based tool and underwent conventional ETDRS visual acuity chart tests supervised at the outpatient clinic under the most ideal circumstances. When performing the test with the web-based tool, patients used a smartphone as a remote control, submitting input from a distance of three metres to a computer screen displaying a sequence of optotypes the user must correctly identify.

The mean difference between the measurements of the webbased tool and the ETDRS chart for the UDVA and CDVA was a value of -0.05±0.10 logMAR and -0.04±0.08 logMAR, respectively. The Pearson correlation coefficients between these tests were 0.94 and 0.89 for the uncorrected and corrected visual acuity measurements, respectively. In total, 82.9% to 88.2% of the visual acuity measurement differences were within the clinically acceptable range of 0.15 logMAR.

The web-based tool was developed by Easee BV in collaboration with the University Medical Centre Utrecht, the Netherlands, and is CE-marked. It is designed for use at home and provides patients with instructions—which are currently available in Dutch, English, and German—to guide them through the test. Dr Wanten noted the web-based tool has shown similar success compared to conventional visual acuity testing in previous studies involving healthy volunteers, keratoconus patients, and uveitis patients.

“The Easee web-based tool has been validated for the assessment of visual acuities in patients who undergo cataract surgery when considering a difference of 0.15 logMAR as clinically acceptable. Future studies need to be conducted to assess the applicability of this tool in regular cataract care,” Dr Wanten concluded.

Dr Wanten presented at the ESCRS Virtual Winter Meeting 2022.

Joukje Wanten MD is a full-time PhD student at the Department of Ophthalmology, University Eye Clinic Maastricht, the Netherlands. joukje.wanten@mumc.nl

The patient uses the web-based tool with a computer at three metres’ distance and a smartphone used as a remote controller. Bland Altman Plot of UDVA determined by the web-based and ETDRS chart. The blue line represents the mean value, and the red dashed lines represent the ±1.96 Standard Deviation (95% limits of agreement).