Purchase this article with an account.
Evelien Vandewalle, Luis A. Pinto, Olof B. Olafsdottir, Ingeborg Stalmans; Phenylephrine Added to Tropicamide Eye Drops Does Not Influence Oxygen Saturation or Vessel Diameter in Oximetry. Invest. Ophthalmol. Vis. Sci. 2012;53(14):5098.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To test whether adding topical phenylephrine 5% to tropicamide 0.5% eye drops in the protocol for pupil dilatation affects the retinal vessel oxymeter measurements in glaucoma patients. To test whether phenylephrine has an influence as a vasoconstrictor on the retinal vessel width and on the quality of the obtained retinal images in glaucoma patients.
Retinal images of 25 primary open-angle glaucoma (POAG) and 26 normal tension glaucoma (NTG) patients were obtained before and after the administration of phenylephrine 5% eyedrops of patients already dilated with tropicamide 0.5% with the Oxymap Retinal Oximeter (Oxymap ehf. Reykjavik, Iceland). Specialized software, Oxymap Analyzer, analyzed the images and measured the oxygen saturation and vessel diameter. Oxygen saturation was measured in first and second degree vessels. A Mann-Whitney U test was used to compare both groups. Quality of the pictures was assessed and a Fisher exact test was used.
There was no significant difference in arterial and venous oxygen saturation in glaucoma patients whether dilated by tropicamide alone or a combination of tropicamide and phenylephrine (99±5% vs 97±4%, p=0.27 and 95±8% vs 95±5%, p=0,77 for arterial saturation and 65±5% vs 65±7%, p=0.86 and 65±5% vs 65±6%, p=0,73 for venous saturation in POAG and NTG, respectively). There was no significant difference in vessel diameter between both protocols for the different vessels (p=0,98 and p=0,27 for arterial saturation and p=0,68 and p=0,20 for venous saturation in respectively POAG and NTG). The quality of the pictures was significant better in the group who received the combination (p=0,0006 and p=0,0001 in respectively POAG and NTG).
The combination of topical phenylephrine 5% and tropicamide 0.5% improved the quality of retinal oximetry images without influencing the oxygen saturation or vessel diameter.
Clinical Trial: :
This PDF is available to Subscribers Only