The OSCAR-IB Consensus Criteria for Retinal OCT Quality Assessment

TLDR

Retinal optical coherence tomography (OCT) is an imaging biomarker for neurodegeneration in multiple sclerosis (MS). Reliable quality control criteria with high inter‑rater agreement are required for OCT to be validated as an outcome measure in multicentre MS studies. The authors developed new consensus QC criteria—OSCAR‑IB—by reviewing literature, applying existing criteria to 101 scans, analysing inter‑rater agreement, identifying disagreement causes, and refining criteria based on seven factors (obvious problems, signal strength, centration, algorithm failure, non‑MS retinal pathology, illumination, beam placement). Applying the OSCAR‑IB criteria raised inter‑rater agreement from moderate (kappa 0.45) to substantial (kappa 0.61) in both training and prospective validation sets, supporting its use in multicentre MS studies.

Abstract

Background Retinal optical coherence tomography (OCT) is an imaging biomarker for neurodegeneration in multiple sclerosis (MS). In order to become validated as an outcome measure in multicenter studies, reliable quality control (QC) criteria with high inter-rater agreement are required. Methods/Principal Findings A prospective multicentre study on developing consensus QC criteria for retinal OCT in MS: (1) a literature review on OCT QC criteria; (2) application of these QC criteria to a training set of 101 retinal OCT scans from patients with MS; (3) kappa statistics for inter-rater agreement; (4) identification reasons for inter-rater disagreement; (5) development of new consensus QC criteria; (6) testing of the new QC criteria on the training set and (7) prospective validation on a new set of 159 OCT scans from patients with MS. The inter-rater agreement for acceptable scans among OCT readers (n = 3) was moderate (kappa 0·45) based on the non-validated QC criteria which were entirely based on the ophthalmological literature. A new set of QC criteria was developed based on recognition of: (O) obvious problems, (S) poor signal strength, (C) centration of scan, (A) algorithm failure, (R) retinal pathology other than MS related, (I) illumination and (B) beam placement. Adhering to these OSCAR-IB QC criteria increased the inter-rater agreement to kappa from moderate to substantial (0.61 training set and 0.61 prospective validation). Conclusions This study presents the first validated consensus QC criteria for retinal OCT reading in MS. The high inter-rater agreement suggests the OSCAR-IB QC criteria to be considered in the context of multicentre studies and trials in MS.