Abstract
Purpose: :
To assess the agreement between the Moorfields MDT perimetry test (Screening Program - ESTA), the HRT-3 (Heidelberg Engineering), the GDx VCC (Zeiss-Meditec), and Goldmann applanation tonometry Intraocular Pressure (IOP) in detecting glaucoma suspects in a randomdly selected sample.
Methods: :
Cross-sectional study with prospective sampling from the Barcelona sanitary register. Over four hundred subjects over the age of 40 yrs were recruited and tested at the primary care center. Two hundred and twenty four subjects whom had images of sufficient quality (GDX images Q≥6; HRT mphsd<25, disk area<2.43 and at least acceptable quality) and reliable MDT results were included in this initial analysis (Age mean= 65yrs range= [40, 87] years). Suspects had abnormal result on Moorfields Regression Analysis (borderline or outside normal limits) on HRT, NFI ≥ 31 on GDx, PTD≥3.5 on the Moorfields MDT or IOP≥21mmHg. Suspect case detection rates for each instrument and agreement between instruments were examined.
Results: :
The difference in the number of suspect cases flagged with the GDx (21.8%) and the MDT (19.2%) was small, the HRT identified slightly more suspect cases (31.7%) and IOP considerably less (8.9%). The agreement between suspect cases for HRT/MDT, GDx/MDT and HRT/GDX was 28.1% (25 subjects), 22.1% (17 subjects) and 28.4% (27 subjects), respectively. Due to the considerably fewer number of cases detected with high IOP, there was much less agreement with IOP/GDx (7.6%), IOP/HRT (7.1%) and IOP/MDT (3.3%). The MDT, GDx and HRT only simultaneously flagged 14 subjects.
Conclusions: :
In this sample the MDT and imaging instruments detected similar numbers of suspects but they tended to be different individuals.
Keywords: clinical (human) or epidemiologic studies: systems/equipment/techniques • imaging/image analysis: clinical • perimetry