Comparison of the iCare rebound tonometer and the Perkins applanation tonometer in children under general anesthesia.

INTRODUCTION: The goal of the study was to compare Perkins applanation tonometry and iCare rebound tonometry, evaluating their correlation and agreement in a diverse pediatric population under general anaesthesia (GA). MATERIALS AND METHODS: Children undergoing an eye examination under GA between November 2019 and March 2020 were included. Intraocular pressure (IOP) was measured successively using the Perkins applanation tonometer and the iCare IC200 rebound tonometer. Ultrasonic central pachymetry and axial length were measured. RESULTS: One hundred and thirty-eight eyes of 72 children were included. The mean age was 2.87years. IOP measurements obtained with the two tonometers were statistically and significantly highly correlated (r=0.8, P<0.001), although the iCare overestimated IOP by an average of 3.37mmHg (SD±4.48). The agreement between the two methods was moderate; the 95% agreement limits ranged from -5.41 to +12.15mmHg (r=0.5, P<0.001). The IOP difference between the two tonometers was weakly but significantly correlated with mean IOP (r=0.52; P=0.006). No correlation was found with axial length and pachymetry. CONCLUSION: In this study, the IOP values obtained using the Perkins applanation tonometer and the iCare IC200 rebound tonometer were well correlated. The iCare tended to overestimate the IOP, especially for high IOP values. However, no underestimation of IOP was found with this device, hence its potential for glaucoma screening in children.

[High-irradiance accelerated corneal collagen crosslinking for the treatment of keratoconus: A retrospective study]. / Étude rétrospective concernant le crosslinking cornéen accéléré avec haute irradiance dans le cadre du traitement du kératocône.

PURPOSE: To evaluate the safety and efficacy of accelerated corneal collagen crosslinking on stabilization of progressive keratoconus. MATERIALS AND METHODS: This was a retrospective study from March 2013 to March 2015. Patients with progressive keratoconus who underwent accelerated corneal collagen crosslinking were included. Visual acuity with and without correction, biomicroscopy, corneal elevation topography (maximum and mean keratometry values, minimum pachymetry, densitometry) and side effects were recorded at baseline and at 1, 3 and 6 months (M). RESULTS: One hundred and ten eyes of 84 patients were included. At month 6, we found an improvement in corrected distance visual acuity (CDVA) with a small improvment of 0.069±0.15 logMAR (P=0.009). Uncorrected distance visual acuity remained unchanged. The mean minimum corneal pachymetry was 455µm at baseline and 449µm at m6 (P<0.001). There was no statistically significant difference between pre- and postoperative mean keratometry values (M1, M3, M6). We likewise found no difference in maximum keratometry between pre- and postoperative values at M1, M3 and M6 (P>0.1). With regard to safety, we report 1 case of postoperative infectious keratitis and 1 case of anterior non-granulomatous uveitis after treatment in patients without any known past ocular history. DISCUSSION: The results we found in this study after accelerated corneal crosslinking are similar to those with conventional crosslinking protocols published in the literature. CONCLUSIONS: High irradiance accelerated corneal collagen crosslinking appears to be a reliable and effective therapeutic alternative for progressive keratoconus, allowing for a more brief procedure.