Analysis of Long-Term Damage Progression in Glaucoma: Comparison between Heidelberg Retina Tomograph II (HRT II) and Visual Field Indices

Abstract

 

Purpose:

 

to evaluate the relationship between Heidelberg Retina Tomograph II (HRT II) and perimetry in determining the progression in glaucoma.

 

Methods:

 

data were obtained from the Glaucoma Management System 3 database of our Glaucoma clinic. We included patients with a diagnosis of open angle glaucoma and reliable HRT II and automated perimetry examinations (Humphrey SITA or full threshold strategy). The following parameters were examined: for HRT rim area (RA) and cup shape measure (CSM), for visual field (VF) the stage of the disease following Brusini’s Glaucoma Staging System 2 (GSS2), mean deviation (MD) and pattern standard deviation (PSD). Patients were included if they had GSS2 ≥ 0.5 at baseline, at least 4 years of follow-up and a minimum of 3 exams for both HRT and VF.

 

Results:

 

58 eyes were eligible for analysis. The mean follow-up was 5.14 years, the mean number of VF was 6.31 and the mean number of HRT was 4.52. Results are summarized in Table 1.

 

Conclusions:

 

a significative reduction over time of global HRT indices (RA and CSM) was paralleled by a significative increase of GSS2 and PSD; MD didn’t show a significative variation at the end of the follow-up, possibly related to these reasons: 1) small sample size, 2) low sensitivity of HRT in evaluating the optic nerve head changes in advanced glaucoma and 3) low sensitivity of MD as a worsening index in the first phases of the disease. Further studies on a larger population are needed to confirm these findings.  

 

Keywords: optic nerve • visual fields