Evolution of electroretinography parameters in Birdshot chorioretinopathy by initial presentation

Theme: Uveitis
What: Uveitis
Part of: Uveitis I: Innovative Imaging Techniques in Uveitis: Exploring Beyond the Traditional. / Uvéite I: Techniques d’imagerie innovantes pour l’uvéite : Explorer au-delà des techniques classiques
When: 5/31/2024, 11:15 AM - 12:45 PM
Where: Room | Salle 714 B

Abstract

Purpose: To characterize the evolution of electroretinography (ERG) parameters in Birdshot chorioretinopathy (BSCR) based on initial presentation.

Study design: Retrospective cohort study.

Methods: Patients with BSCR followed by the uveitis service of the Centre universitaire d’ophtalmologie – Hôpital Maisonneuve-Rosemont with ERG were considered for inclusion (n=100). These were categorized based on initial presentation: inflammatory presentation with hot disc, vasculitis, and cystoid macular edema (CME); CME only; and no inflammatory component. Systematic ERG monitoring was started around 2015 and consisted in measurements of cones a-wave response, cones b-wave response, retinal ganglion cell (RGC) PhNR response, rods b-wave response, rods-cones a-wave response, and rods-cones b-wave response. Differences between initial and final ERG parameters were compared using Wilcoxon signed-rank test and subsequently compared between presentation groups. Significance was adjusted for multiple comparisons using Bonferroni correction and significance was set at 0.008.

Results: Median [Q1, Q3] age at presentation was 58 [52, 64] years and 57% were female. Follow-up time was 5.0 [3.1, 6.4] years. Initial and final cones a-wave responses were 20.6 [15.5, 27.1] and 20.2 [14.8, 25.2] (p=0.049), cones b-wave response were 62.6 [41.0, 89.4] and 60.3 [39.0, 81.3] (p=0.002), retinal ganglion cell (RGC) PhNR response were 13.4 [7.8, 20.1] and 13.0 [7.0, 18.1] (p=0.731), rods b-wave response were 84.7 [52.1, 114.1] and 81.3 [47.9, 104.0] (p=0.007), rods-cones a-wave response 102.1 [73.1, 134.5] and 104.9 [80.5, 132.1] (p=0.002), and rods-cones b-wave response were 187.2 [122.6, 234.1] and 189.9 [131.3, 223.1] (p=0.33).

There was data on initial presentation in 78 patients (156 eyes). Of these, 7 (9%) had inflammatory presentations, 13 (17%) had CME only presentations, and 58 (74%) had non-inflammatory presentations. When comparing differences in initial and final ERG measurements by presentation, there were no significant differences between presentations (p>0.05). There was however a possible signal in cones b-wave response with -4.4 [-21.2, 3.6] in inflammatory patients, -7.9 [-15.6, 0.7] in CME only patients, and -0.49 [-10.7, 7.6] in non-inflammatory patients (p=0.031).

Conclusions: There are multiple differences in ERG parameters between initial and final follow-ups in BSCR patients, particularly cones b-wave response, rods b-wave response, and rods-cones a-wave response. This did not however differ based on initial presentation.

Presenter(s)

Presenting Author: Mélanie Hébert

Additional Author(s):

Daniel Chow, McGill University

Anna Polosa, Hôpital Maisonneuve-Rosemont

Marie-Josée Aubin, Université de Montreal

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