Diameters and wall-to-lumen ratio of retinal arterioles in patients with retinal vein occlusion before and after treatment with dexamethasone intravitreal implants.
BACKGROUND
To evaluate the diameters and wall-to-lumen ratio (WLR) of retinal arterioles in patients with retinal vein occlusion (RVO) before and after a 0.7 mg dexamethasone (DEX) intravitreal implant and compare it with a matched control group of normal eyes.


METHODS
This was a single-site, multi-investigator, prospective, open-label, observational study in 15 patients with vision loss due to branch or central RVO treated with a single injection of DEX implant. An age-matched control group of 16 normal eyes was recruited. External and internal arteriolar diameters, WLR, and wall thickness were assessed in vivo using scanning-laser Doppler flowmetry. Visual acuity (VA) and central macular thickness (CMT) were evaluated.


RESULTS
Mean internal diameter showed a significant reduction in post-treatment RVO patients compared with pre-treatment RVO patients (56.0±18.0 μm vs. 67.9±16.9 μm, respectively; P=0.02). Mean WLR in pre-treatment RVO patients was 0.47±0.19, showing an increase to 0.63±0.23 3 months after treatment (P=0.037). No significant difference was found in arteriolar external diameter between normotensive, pre-treatment, and post-treatment subjects.


CONCLUSIONS
Treatment with a DEX implant in RVO patients led to significant improvements in both VA and CMT. These changes were accompanied by reductions in arteriolar lumen diameter, which could contribute to decreased capillary leakage and macular swelling.
1 Eye Clinic, Department of Neurological and Vision Sciences, University of Brescia , Brescia, Italy .
Francesco
F
Semeraro
Andrea
A
Russo
Damiano
D
Rizzoni
Paola
P
Danzi
Francesco
F
Morescalchi
Ciro
C
Costagliola
D000368:Aged; D001160:Arterioles / Q000187:drug effects* / Q000473:pathology; D003907:Dexamethasone / Q000008:administration & dosage / Q000627:therapeutic use*; D004343:Drug Implants / Q000008:administration & dosage / Q000627:therapeutic use; D005260:Female; D006801:Humans; D058449:Intravitreal Injections; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012161:Retinal Artery / Q000187:drug effects* / Q000473:pathology; D012170:Retinal Vein Occlusion / Q000188:drug therapy* / Q000473:pathology; D016896:Treatment Outcome
D004343:Drug Implants; D003907:Dexamethasone