Glaucoma filtration surgery and retinal oxygen saturation.
OBJECTIVE
Glaucoma may involve disturbances in retinal oxygenation and blood flow. The purpose of this study was to measure the effect of glaucoma filtration surgery on retinal vessel oxygen saturation.


METHODS
A noninvasive spectrophotometric retinal oximeter was used to measure hemoglobin oxygen saturation in retinal arterioles and venules before and after glaucoma filtration surgery. Twenty-five consecutive patients were recruited, and 19 had adequate image quality. Fourteen underwent trabeculectomy and five glaucoma tube surgery. Twelve had primary open-angle glaucoma and seven had exfoliative glaucoma. IOP decreased from 23 +/- 7 to 10 +/- 4 mm Hg (mean +/- SD, P = 0.0001).


RESULTS
Oxygen saturation increased in retinal arterioles from 97% +/- 4% to 99% +/- 6% (n = 19; P = 0.046) after surgery and was unchanged in venules (63% +/- 5% before surgery and 64% +/- 6% after, P = 0.76). There were no significant changes in saturation in the fellow eyes (P > 0.60). The arteriovenous difference was 34% before and 36% after surgery (P = 0.35).


CONCLUSIONS
Glaucoma filtration surgery had almost no effect on retinal vessel oxygen saturation.
Hardarson
Sveinn Hakon
SH
Department of Ophthalmology, University of Iceland/Landspítali-University Hospital, Reykjavik, Iceland.
Gottfredsdottir
Maria Soffia
MS
Halldorsson
Gisli Hreinn
GH
Karlsson
Robert Arnar
RA
Benediktsson
Jon Atli
JA
Eysteinsson
Thor
T
Beach
James M
JM
Harris
Alon
A
Stefansson
Einar
E
D000368:Aged; D005260:Female; D020327:Glaucoma Drainage Implants; D005902:Glaucoma, Open-Angle / Q000097:blood* / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D010092:Oximetry / Q000379:methods; D010100:Oxygen / Q000097:blood*; D010108:Oxyhemoglobins / Q000032:analysis; D012039:Regional Blood Flow / Q000502:physiology; D012171:Retinal Vessels / Q000378:metabolism*; D014130:Trabeculectomy
D010108:Oxyhemoglobins; D010100:Oxygen