Clinicians’ Agreement in Establishing Glaucomatous Progression Using the HRT Topographic Change Analysis (TCA), Trend Analysis (TA) and Moorfields Regression Analysis (MRA)

Abstract

Purpose: : To assess the degree of concordance among clinicians reviewing three HRT printouts to detect progression, the TCA, the TA and the MRA, and to compare the results with progression by stereophotographs.

Methods: : Three experienced observers (GV, JMC and LA) judged the presence of progression using the HRT follow-up printouts available for each HRT method of analysis (TCA, TA, MRA). The overall assessment was based on majority rule, with at least two graders agreeing on the classification. Agreement for progression or no progression between the HRT methods of analysis and the reference standard represented by stereophotographs was also evaluated. The kappa test was used to assess the interobserver agreement.

Results: : 136 eyes of 112 patients (53 glaucomatous eyes, 83 glaucoma suspects) from the Diagnostic Innovations in Glaucoma Study (DIGS) were followed up longitudinally for 50.8 (S.D.= 11.1) months, with a minimum of 4 HRT images (range 4-7). 16 of 136 (11.8%) eyes were found to progress during follow-up based on stereophotographs assessment. Agreement among clinicians for subjective assessment of progression was fair to moderate, with better agreement for TCA and TA than for the MRA analysis (kappas ranging from 0.28 to 0.5 for MRA, 0.36 to 0.53 for TCA and 0.26 to 0.61 for TA). Agreement for progression/no progression between the HRT methods and stereophotography was similar for TCA, (75%, agreement on 6 progressing eyes and 96 non progressing eyes, kappa= 0.13), TA (74%, agreement on 4 progressing eyes and 97 non progressing eyes, kappa= 0.04) and MRA (76%, agreement on 2 progressing eyes and 102 non progressing eyes, kappa= -0.02).

Conclusions: : Clinicians’ agreement in establishing glaucomatous progression using different HRT methods of analysis was only fair to moderate and was better for the methods originally designed to detect progression (TCA and TA) than MRA, which is not designed to detect progression but is likely used for this purpose. Agreement between TCA and stereophotographs was similar to previous reports. Further studies are needed to establish predefined objective criteria for detecting change over time that can be used to assess progression with HRT in clinical practice.

Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • optic disc • imaging/image analysis: clinical