Non-contact screening methods for the detection of narrow AC angles
Research type
Research Study
Full title
A methods comparison study of non-contact screening methods for the detection of narrow anterior chamber angles.
IRAS ID
114137
Contact name
Ian Murdoch
Contact email
Sponsor organisation
City University
Research summary
Angle closure glaucoma (ACG) is a major cause of visual morbidity, in which significant and irreversible impairment of visual function can occur within a short period. Reports documenting the nature of ACG presentations have identified the chronic sub-type as the most common condition. With fewer symptoms reported at the point of diagnosis, detection of the disease before significant damage has already occurred remains a significant challenge. However, with timely detection of anatomically narrow angle eyes at risk of angle-closure, and the subsequent administration of preventative therapy, the progression of the disease process can be arrested. Detection of narrow angles is based on the structural evaluation of the anterior chamber angle configuration. Gonioscopy is the current gold standard method of examination. However, in recent years, its status as an ideal reference standard has been brought into question. Community optometrists are responsible for referring the vast majority of suspected glaucoma patients for ophthalmological opinion. However, the majority of community optometrists lack the training to perform gonioscopy, using alternative non-invasive screening methods for angle closure. These include slit-lamp microscope-based techniques, and more recently, optical imaging-based systems. The aim of this study is to determine whether various non-contact screening methods that measure peripheral and central anterior chamber depth can be used to reliably identify individuals at risk of angle closure. The study design proposed requires every participant to undergo a full gonioscopic examination, and non-invasive screening tests performed by experienced examiners who will be masked to the findings of all other investigations. Evidence from the current study on the reliability and validity of alternative non-invasive techniques will be used to inform good practice guidance for optometrists. Further data processing will include combined analysis of diagnostic tests in an effort to increase the accuracy of referrals from community optometrists for further evaluation in secondary care.
REC name
London - Bromley Research Ethics Committee
REC reference
13/LO/1923
Date of REC Opinion
21 Jan 2014
REC opinion
Further Information Favourable Opinion