# Validation of iCare IC200 tonometry during natural sleep in children under 3 years with glaucoma: reducing anesthesia dependence in clinical monitoring

## TL;DR

The study shows that measuring eye pressure in sleeping children with glaucoma can reduce the need for anesthesia.

## Contribution

Demonstrates the validity of non-anesthetic IOP measurements in young glaucoma patients.

## Key findings

- Natural sleep IOP measurements were consistently higher than those under anesthesia.
- A strong correlation (r = 0.95) was found between sleep and anesthesia IOP measurements.
- Anesthesia use decreased by 40% with the new monitoring approach.

## Abstract

To assess the agreement between intraocular pressure (IOP) measurements obtained with the iCare IC200 rebound tonometer during natural sleep and under general anesthesia (EUA) in children under 3 years of age with glaucoma, and to evaluate the impact of this approach on clinical follow-up frequency and anesthesia exposure.

This prospective study included 74 eye-session pairs from 74 eyes of 27 patients aged 0–36 months diagnosed with pediatric glaucoma. IOP was measured during natural sleep within ≤ 2 h prior to EUA under end-tidal sevoflurane 2–3%. Measurements were performed by the same examiner under both conditions. Office and EUA frequencies were compared to a historical cohort (2009–2012) to evaluate changes in clinical monitoring trends.

Mean age was 18.07 ± 13.97 months; 78% had primary congenital glaucoma. Natural sleep IOP (21.01 ± 11.77 mmHg) was consistently higher than EUA IOP (17.69 ± 9.85 mmHg), with mean difference of 3.32 ± 3.83 mmHg (14.96 ± 16.60%) (p < 0.05). A very strong correlation was observed between the two measurement conditions (r = 0.95, R² = 0.91). Current surveillance demonstrated 4.45 ± 2.70 EUA procedures versus 3.18 ± 2.44 office visits per patient, compared to pre-iCare era ratio of 7.39 ± 2.65 EUA versus 0.80 ± 0.70 office visits, representing a 40% reduction in anesthesia dependence.

Natural-sleep rebound tonometry supports bias-aware, clinic-based trend monitoring and can reduce anesthesia exposure in children under 3 years.

The online version contains supplementary material available at 10.1186/s12886-025-04549-z.