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Retinal arteriolar changes in malignant arterial hypertension.
S S Hayreh1, G E Servais, P S Virdi
1Department of Ophthalmology University of Iowa, Iowa City.
Summary
This study investigated retinal arteriolar changes in rhesus monkeys with experimental renovascular malignant arterial hypertension. Findings revealed arteriolar sclerosis, tortuosity, narrowing, and occlusion, but no evidence of arteriolar spasm.
Area of Science:
- Ophthalmology
- Cardiovascular Research
- Nephrology
Background:
- Malignant arterial hypertension can cause significant ocular complications.
- Understanding retinal arteriolar changes is crucial for diagnosing and managing hypertensive retinopathy.
Purpose of the Study:
- To detail the retinal arteriolar changes in a primate model of renovascular malignant arterial hypertension.
- To investigate the presence and nature of arteriolar narrowing and 'spasm' in hypertensive retinopathy.
Main Methods:
- Experimental renovascular malignant arterial hypertension induced via modified Goldblatt procedures in 60 rhesus monkeys.
- Serial ophthalmoscopy, stereoscopic color fundus photography, and fluorescein fundus angiography for long-term follow-up.
- Detailed examination of retinal arteriolar morphology and changes.
Main Results:
- Observed arteriolar sclerosis, increased tortuosity, narrowing, and occlusion/sheathing of fine retinal arterioles.
- Identified focal dilatation and leakage of terminal arterioles, leading to transudates and cotton-wool spots in accelerated hypertension.
- Found no evidence of localized or generalized arteriolar 'spasm' in retinal arterioles.
Conclusions:
- Retinal arteriolar changes in malignant hypertension include sclerosis, tortuosity, and occlusion, consistent with microvascular damage.
- Focal arteriolar dilatation and leakage are associated with accelerated hypertension and intraretinal abnormalities.
- The study questions the role of 'spasm' in ophthalmoscopically visible retinal arterioles during malignant hypertension.