Higher retinal vessel oxygen saturation: investigating its relationship with macular oedema in retinitis pigmentosa patients

Publication

Higher retinal vessel oxygen saturation: investigating its relationship with macular oedema in retinitis pigmentosa patients

Journal Paper/Review - Mar 6, 2018

Bojinova Rossiana I, Schorderet Daniel F, Valmaggia Christophe, Türksever Cengiz, Schoetzau Andreas, Todorova Margarita

Citation

Bojinova R, Schorderet D, Valmaggia C, Türksever C, Schoetzau A, Todorova M. Higher retinal vessel oxygen saturation: investigating its relationship with macular oedema in retinitis pigmentosa patients. Eye (Lond) 2018

Type

Journal Paper/Review (English)

Journal

Eye (Lond) 2018

Publication Date

Mar 6, 2018

Issn Electronic

1476-5454

Brief description/objective

PURPOSE
Primary objective-to investigate the effect of retinal vessel oxygen saturation (SO) on macular oedema (ME) in retinitis pigmentosa (RP) patients. Secondary objective-to link the presence of ME to metabolic (oxygen saturation of retinal vessels, SO), functional (multifocal electroretinography, mfERG) and structural (Spectral Domain Optical Coherent Tomography, SD-OCT) alterations in RP.

DESIGN
Prospective, cross-sectional, non-interventional study.

SUBJECTS
Patients with typical RP (N = 37) and controls (N = 19), who underwent retinal vessel Oximetry (RO), SD-OCT and mfERG, were included.

METHODS
A computer-based program of the retinal vessel analyser unit (IMEDOS Systems UG, Jena, Germany) was used to measure SO. We evaluated the mean SO, in all major retinal arterioles (oxygen saturation in retinal arterioles, A-SO, %) and venules (oxygen saturation in retinal venules, V-SO, %). MfERG responses were averaged in zones (zone 1 (0-3°), zone 2 (3-8°) and zone 3 (8-15°)) and compared to corresponding areas of the OCT. The effect of ME on SO was evaluated dividing the RP in two subgroups: with clinical appearance of ME (ME-RP) and without it (no-ME-RP).

MAIN OUTCOME MEASURES
Parallel recording and juxtaposition of metabolic (SO) to structural (OCT) and functional-(mfERG) measures. Mean ( ± SD) A-SO and V-SO were higher in no-ME-RP (96.77% (±6.31) and 59.93% (±7.76)) and even higher in the ME-RP (99.82% (±6.21) and 65.63% (±7.63)), compared to controls (93.15% (±3.76) and 53.77% (±3.70), p ≤ 0.006).

RESULTS
The subgroup ME-RP differed significantly from the subgroup no-ME-RP by increased A-SO and V-SO, p ≤ 0.026. The presence of ME confirmed a different relationship between the altered SO and the vessel diameters, against the functional and structural parameters.

CONCLUSION
Based on our results, the presence of macular oedema indicates a tendency toward greater alteration of the metabolic function in RP patients.