Impaired retinal autoregulation in small retinal arterioles before and after focal laser treatment for diabetic maculopathy
- 1Department of Ophthalmology, Århus University Hospital, Denmark
- 2Department of Ophthalmology, Århus University Hospital, Nørrebrogade 44, 8000 Århus C, Denmark
- Correspondence to: P Jeppesen Department of Ophthalmology, Århus University Hospital, Denmark; pj{at}dadlnet.dk
- Accepted 2 October 2005
Abstract
Aims: To study the effect of an acute increase in the arterial blood pressure on the diameter response of retinal arterioles supplying areas with focal diabetic macular oedema before and after laser photocoagulation, and control arterioles supplying areas without oedema.
Methods: In 17 diabetic patients the diameter response of arterioles after an increase in the arterial blood pressure induced by isometric exercise was studied using the retinal vessel analyser (RVA). In each patient a study arteriole supplying a focal area of macular oedema as well as a control arteriole supplying a retinal area without retinopathy lesions was selected, and the diameter response of these vessels was performed immediately before, and 1 hour and 3 months after focal laser photocoagulation of the focal oedema area.
Results: The diameter response was impaired in both study arterioles and control arterioles before focal laser photocoagulation. The treatment induced regression of the focal retinal oedema, but did not affect the diameter response in the arteriole supplying this area (p = 0.85).
Conclusion: Impairment of the diameter response in small arterioles from diabetic patients does not parallel the regional distribution of retinopathy lesions. Other factors than disturbed autoregulation are probably involved in generating flow disturbances and oedema in diabetic maculopathy.
- AU, arbitrary units
- HE, hard exudates
- MAP, arterial pressure
- ROI, region of interest
- RVA, retinal vessel analyser
- TP, transmural pressure
- VA, visual acuity
- retinal vessels
- autoregulation
- myogenic response
- retinal vessel analyser
- diabetic maculopathy
- AU, arbitrary units
- HE, hard exudates
- MAP, arterial pressure
- ROI, region of interest
- RVA, retinal vessel analyser
- TP, transmural pressure
- VA, visual acuity
- retinal vessels
- autoregulation
- myogenic response
- retinal vessel analyser
- diabetic maculopathy
Footnotes
-
Grant support: Danish Diabetes Association, The Association “Værn om Synet,” The VELUX Foundation, The Danish Medical Research Council.
-
Competing interests: none declared
-
Ethics approval: All examinations were approved by the local committee for scientific ethics, Den videnskabsetiske Komité for Århus Amt, Lyseng Allé 1, 8270 Højbjerg, Denmark.
