Article Text

Download PDFPDF
Characterisation of macular superficial vessel density alteration in preclinical ethambutol-induced optic neuropathy using optical coherence tomography angiography

Abstract

Aim To investigate the changes in macular vessel density (mVD) and its relationship to macular ganglion cell–inner plexiform layer (mGCIPL) thickness in patients receiving ethambutol (EMB) therapy for tuberculosis without recognisable clinical symptoms or signs of EMB-induced optic neuropathy (EON).

Methods A total of 23 eyes of 13 patients using EMB therapy for 6 months without EON (preclinical EON) as the EMB group, 40 eyes of 23 healthy individuals as the normal control group and 18 eyes of 10 patients with tuberculosis before receiving EMB therapy as the blank control group were retrospectively analysed. The mean peripapillary retinal nerve fibre layer (pRNFL) and mGCIPL thicknesses and mVD were measured using optical coherence tomography angiography. Patients in the EMB group were compared with individuals in the normal and blank control groups, and changes in macular parameters were evaluated.

Results Central circle mVD (cCVD) was significantly lower in the EMB group than in both control groups (generalised estimating equation (GEE), p=0.003 and 0.029, respectively). The mGCIPL thickness in all regions and the mean pRNFL thickness were not significantly different between the EMB group and both control groups (GEE, p=1.000 for all). There were no significant differences in mVD, mGCIPL thickness and mean pRNFL thickness between the normal control and blank control groups (p>0.05). In the generalised linear model analyses, the minimum and inferonasal mGCIPL thicknesses were positively correlated with cCVD in the EMB group (β=1.285, p=0.003 and β=0.770, p=0.024, respectively).

Conclusions cCVD decreased with no changes in mGCIPL and mean pRNFL thicknesses in patients with preclinical EON. The minimum and inferonasal mGCIPL thicknesses were positively correlated with cCVD. cCVD might be an early indicator for monitoring early-stage EMB toxicity.

  • macula
  • retina

Data availability statement

All data relevant to the study are included in the article or uploaded as supplementary information. The medical records of patients who were diagnosed with tuberculosis in our hospital between July 2019 and June 2020 were retrospectively reviewed.

Statistics from Altmetric.com

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.

Linked Articles

  • At a glance
    Frank Larkin