[Haemoglobin oxygenation of retinal vessels in branch retinal artery occlusions over time and correlation with clinical outcome].
OBJECTIVE
Purpose of these study was the evaluation of a new method for the measurement of haemoglobin oxygenation in retinal vessels. Patients with branch retinal artery occlusion have been measured before and after a rheological therapy.


METHODS
The haemoglobin oxygenation in retinal vessels was measured by the "oxygen module" (Imedos GmbH, Jena, Germany) which uses a special filter (transmission at 548 and 610 nm, band width 10 nm) in the illumination path of a fundus camera. Fundus images were acquired by a colour CCD camera and specific software was used for vessel tracking and calculation of their haemoglobin oxygen saturation. 11 patients with branch retinal artery occlusions, average age 63.4 ± 11.7 years were investigated at time of diagnosis and at the 5th day of a rheological and intraocular pressure reduction therapy.


RESULTS
10 out of 11 patients have shown an increase of haemoglobin oxygenation over time (on average from 73 ± 16 % to 87 ± 11 %). This increase was statistically significant (p < 0.05, Wilcoxon test). Non-affected retinal areas have also shown an increase of haemoglobin oxygenation. The visual acuity improved by one line. This increase in visual acuity was, however, not statistically significant.


CONCLUSIONS
We observed an increase of the arterial haemoglobin oxygenation. One possible reason of the improvement of the haemoglobin oxygenation by the therapy may be an increase of the rheological properties of the blood. All patients showed an increase or at least a stabilisation of their visual acuity. Retinal vessel oximetry might be used as an additional parameter in the follow-up of retinal artery occlusion.
Gehlert
S
S
Klinik für Augenheilkunde, Universitätsklinikum Jena, Jena. simone.gehlert@med.uni-jena.de
Dawczynski
J
J
Hammer
M
M
Strobel
J
J
D015415:Biomarkers / Q000097:blood; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010092:Oximetry / Q000295:instrumentation*; D010108:Oxyhemoglobins / Q000032:analysis*; D011379:Prognosis; D015203:Reproducibility of Results; D012161:Retinal Artery / Q000378:metabolism*; D015356:Retinal Artery Occlusion / Q000097:blood* / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D013223:Statistics as Topic; D016896:Treatment Outcome
D015415:Biomarkers; D010108:Oxyhemoglobins