Hypertensive Retinopathy and Sclerotic Changes
Arterial changes in hypertension are primarily caused by vasospasm; in arterio-sclerosis they are the result of thickening of the wall of the arteriole.
Arterial hypertension in particular figures prominently inclinical settings.
Vascular changes due to arterial hypertension are the most frequent cause of retinal vein occlusion.
High blood pressure can cause breakdown of the blood-retinabarrier or obliteration of capillaries. This results in intraretinal bleeding, cot-ton-wool spots, retinal edema, or swelling of the optic disk.
Patients with high blood pressure frequently suffer from head-ache or eye pain. Impaired vision or loss of visual acuity only occurs in stage III or IV hypertensive vascular changes. Arteriosclerosis does not exhibit any ocular symptoms.
Hypertensive and arteriosclerotic changes in thefundus are diagnosed by ophthalmoscopy, preferably with the pupil dilated (Tables 12.3 and 12.4). Changes in the retinal vasculature are frequent find-ings; choroidal infarctions are rare in acute hypertension (Elschnigâ€™s spots: circumscribed atrophy and proliferation of pigment epithelium in the infarcted area).
Ophthalmoscopy should be performed to excludeother vascular retinal disorders such as diabetic retinopathy. Diabetic reti-nopathy is primarily characterized by parenchymal and vascular changes; a differential diagnosis is made by confirming or excluding the systemic under-lying disorder.
Treating the underlying disorder is crucial where fundus changesdue to arterial retinopathy are present. Blood pressure should be reduced to below 140/90 mm Hg. Fundus changes due to arteriosclerosis are untreat-able.
Regular blood pressure monitoring and ophthalmoscopicexamination of the fundus are required to minimize the risk of complications (see below).
Sequelae of arteriosclerotic and hyper-tensive vascular changes include retinal artery and vein occlusion and the for-mation of macroaneurysms that can lead to vitreous hemorrhage. In the pres-ence of papilledema, the subsequent atrophy of the optic nerve can produce lasting and occasionally severe loss of visual acuity.
In some cases, the complications described above are unavoidable despite well controlled blood pressure.