Abstract
Purpose:
To compare agreement between ophthalmologists and non-ophthalmologists (nurses and ophthalmic technicians) when measuring the intraocular pressure (IOP) using applanation tonometry (Tonosafe disposable prism) and Pascal dynamic contour tonometry (DCT).
Methods:
Patients attending for their routine glaucoma outpatient appointment at Moorfields Eye Hospital, London, were invited to participate. IOP was measured in one eye by either 2 ophthalmologists (observer Group 1), one ophthalmologist and one non-ophthalmologist (observer Group 2), or 2 non-ophthalmologists (observer Group 3). All had experience in using applanation tonometry, but less experienced using the DCT. The order of tonometer and staff was randomised. Agreement was calculated by Bland Altman analysis, with the mean difference and 95% limits of agreement (LoA) of measurements calculated for each observer group.
Results:
The results for 100 eyes within observer groups 1 & 2 and 88 eyes for observer group 3 (total n = 288 eyes) are presented. The mean difference [95% LoA] in IOP measurements were: Tonosafe : Group 1 = -0.25 [4.81] mmHg, Group 2 = 0.04 [3.74] mmHg, Group 3 = 0.46 [4.94] mmHg; DCT: Group 1 = 0.68 [7.14] mmHg, Group 2 = 0.05 [5.20], Group 3 = 0.22 [3.61] mmHg.
Conclusions:
Ophthalmologists show good levels of agreement with each other when using applanation tonometry, whilst technicians/nurses show better agreement when measuring IOP with the DCT. Ophthalmologists and technicians/nurses show best agreement when using applanation tonometry, and thus this measurement may be delegated to non-ophthalmologist support staff. The study is ongoing and aims to collect 100 eyes for each observer group (total n = 300).
Keywords: 568 intraocular pressure