Clinical Publications

TRITON

Sub-clinical thickening of the fovea in diabetes and its relationship to glycaemic control: a study using swept-source optical coherence

AUTHORS:

Aitchison RT, Kennedy GJ, Shu X, Mansfield DC, Shahani U.

PUBLICATION:

Graefe’s Archive for Clinical and Experimental Ophthalmology (2021) 259: 633-641. DOI: 10.1007/s00417-020-04914-2

Study Purpose

This study aimed to use swept-source optical coherence tomography (SS-OCT) to measure foveal thickness and macular volume in diabetic individuals without cystoid macular oedema, and in non-diabetic individuals, and relate these measures to participants’ glycaemic control.

Overview

Study Design

Cross-sectional study

# of Eyes/
Patients

• Fifty-four Caucasian participants • Diabetic n=27( type 1 n=7, type 2 n=20), non-diabetic n=27

Study Device

DRI Triton SS-OCT (Topcon, Tokyo, Japan)

Outcome Measures

• Center Point Thickness (CPT) which was the distance between the inner limiting membrane and the outer segment retinal pigment epithelium interface. Measured at the foveola: the locus of the intersection of the six radial scans comprising the 3D macula scan • Total macular volume (TMV) in mm3 calculated using the mean thickness in microns of each of the 9 sub fields of the EDTRS grid. • HbA1c levels

Results

Diabetic individuals had a statistically significantly greater CPT compared with their non-diabetic counterparts (p=0.0005).
HbA1c level significantly predicted the CPT in the diabetic group (p=0.0005), with a 19µm increase in CPT for every 1% increase in HbA1c level.
Individuals with type 1 diabetes had greater CPT than those with type 2, the difference was not statistically significant.
There was no significant difference between the diabetic and non-diabetic groups for TMV.
HbA1c level did not predict TMV in either group

IMOvifa reduced measurement time by

39%

Conclusions

• The authors stated that the use of SS-OCT is the only way to quantifiably measure foveolar thickness in vivo. • Diabetic individuals had significantly greater foveolar thickness compared with their age- and sex-matched non-diabetic counterparts. • The authors suggest that the more severe abnormality of DCMO might be preceded by a pre-clinical phase of non-cystoid thickening.