Format

Send to

Choose Destination
Br J Ophthalmol. 2018 Apr 29. pii: bjophthalmol-2017-311392. doi: 10.1136/bjophthalmol-2017-311392. [Epub ahead of print]

Retrospective cohort study exploring whether an association exists between spatial distribution of cystoid spaces in cystoid macular oedema secondary to retinitis pigmentosa and response to treatment with carbonic anhydrase inhibitors.

Author information

1
UCL Institute of Ophthalmology, University College London, London, UK.
2
Moorfields Eye Hospital NHS Foundation Trust, London, UK.
3
UCL Institute of Ophthalmology, University College London, London, UK michel.michaelides@ucl.ac.uk.

Abstract

BACKGROUND:

Carbonic anhydrase inhibitors (CAIs) are frequently used as an initial step to treat retinitis pigmentosa-associated cystoid macular oedema (RP-CMO). Interestingly, it has been postulated that CAIs might reduce outer nuclear layer (ONL) fluid more effectively than inner nuclear layer (INL) fluid due to better access to retinal pigment epithelium basolateral membrane than neurosensory retina. This retrospective cohort study explores if an association between spatial distribution of cystoid spaces in RP-CMO and CAI response exists.

METHODS:

Two independent graders reviewed pretreatment and post-treatment optical coherence tomography (OCT) images of 25 patients (43 eyes) initiated on topical and/or oral CAIs between January 2013 and December 2014. Documentation included the presence/absence of fluid (and layer(s) involved), external limiting membrane, epiretinal membrane (ERM), vitreomacular adhesion/traction, lamellar/full-thickness macular hole and central macular thickness (CMT)/volume.

RESULTS:

INL fluid was found in all study eyes. All 13 'responders' (at least 11% reduction of CMT after treatment) demonstrated pretreatment ONL fluid. In seven patients (four responders and three non-responders), complete clearance of ONL fluid was achieved despite persistence of INL fluid. ERM presence was similar in responders and non-responders.

CONCLUSION:

In this study, INL fluid was found to be the most common spatial distribution of RP-CMO. However, patients who were classed as a 'responder' to CAI treatment all demonstrated coexisting ONL fluid on their pretreatment OCT scans. This may be explained by CAIs having better access to retinal pigment epithelium basolateral membrane than neurosensory retina. Our study also suggests a minimal impact on response to CAIs by ERM.

KEYWORDS:

carbonic anhydrase inhibitor; cystoid macular oedema; imaging; macular oedema; optical coherence tomography; retinal diseases; retinitis pigmentosa

Conflict of interest statement

Competing interests: None declared.

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center