Purchase this article with an account.
Jonathan Jan-Ming Tsang, Rupal Morjaria, Hina Khan, Robert Carmichael, Philip Ian Murray, Pearse Andrew Keane, Alastair K Denniston; Evaluating the utility of different non-invasive imaging modalities for the diagnosis and monitoring of Birdshot Chorioretinopathy. Invest. Ophthalmol. Vis. Sci. 2018;59(9):4202.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Monitoring Birdshot Chorioretinopathy (BCR) is difficult due to its insidious nature and variable peripheral and central manifestations of disease. Multimodal imaging can support diagnosis and monitoring of BCR, but the relative value of different modalities is not established. The purpose of this study was to evaluate the feasibility and utility of a range of scanning protocols in a well-characterised cohort of BCR patients.
Design: Prospective observational (imaging) study. Setting: Dedicated BCR Clinic at the Centre for Rare Diseases, Birmingham, UK. Inclusion: All BCR patients. Imaging protocol: Heidelberg Spectralis+30° lens - OCT (macula, RNFL), IR, autofluorescence (AF), multicolor (MC); 55° lens – OCT, IR, AF, MC; Optos (200° Colour, AF). Analysis: Qualitative for feasibility and utility; quantitative for central macula thickness (CMT), minimum and maximum macula thickness (MiMT, MaMT), RNFL thickness, retinal volume (RV), outer retina volume (ORV) and inner retina volume (IRV).
Analysis was undertaken of 140 imaging sets (each comprising up to 11 scan-types/eye) from 48 eyes of 24 patients with BCR. Cohort: mean age 58.3 years (range: 45-81 years); 63% female. Visual function: 50% reduced colour vision; 17% VA<20/40. Features: 79% birdshot spots, 29% vitritis, 8% CME, 17% retinal vasculitis, 4% disc swelling. Complications: 88% epi-retinal membrane. Active disease was present in 33% of patients. Imaging: Feasibility analysis, all modalities were possible in 100%. Utility analysis, most helpful modalities for diagnosis was Optos, for monitoring disease activity was 30° macular OCT (CMO, vitritis) and RNFL (swelling), for detecting disease complications (eg. ERM) was 30° macular OCT; 55° OCT and BAF modalities were of value in detecting/monitoring extramacular involvement. Patients with active disease tended to have fluctuating values for retinal thickness, volume, and RNFL; even when apparently 'inactive', progressive retinal loss occured at 4.6μm/year (CMT), 9.7μm/year (MaMT), 0.05mm3/year (IRV), 0.02mm3/year (ORV).
Multimodal imaging can support diagnosis and monitoring of BCR. The Birmingham protocol combines macular and wide-field modalities to improve detection of central and peripheral signs of activity and damage. Quantitative imaging will improve titration of treatment and should be developed across all modalities.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.
This PDF is available to Subscribers Only