Macular circulation in patients with diabetes mellitus with and without arterial hypertension

Abstract

Background-Previous fluorescein angiographic studies have shown alterations in the macular microcirculation in patients with diabetes mellitus and arterial hypertension. In both diseases capillary blood velocity was reduced and capillary density decreased. These changes were more pronounced in diabetic patients. We have examined the influence of arterial hypertension in combination with diabetes mellitus. Methods-62 patients with diabetes mellitus and arterial hypertension (group 1) were matched with patients with diabetes mellitus but without arterial hypertension (group 2, match criteria: ETDRS stage of retinopathy). In all subjects fluorescein angiograms were performed with a scanning laser ophthalmoscope. Macular capillary blood velocity (CBV), perifoveal intercapillary area (PIA), the coeYcient of variation of both parameters, the area of the foveal avascular zone (FAZ), and the arteriovenous passage time (AVP) were assessed by digital image analysis. 2 (group 2)) were significantly diVerent between the two groups of diabetic patients. Conclusion-Arterial hypertension did not result in more severe macular capillary dropout than diabetes without hypertension. This might be explained by the fact that most of the patients were being treated with antihypertensive drugs. (Br J Ophthalmol 2000;84:1392-1396 Retinal changes associated with arterial hypertension and diabetes mellitus have been well documented. Considering the frequent coincidence of both diseases, it is important for both the prognosis and treatment to determine whether arterial hypertension aggravates diabetic retinopathy. A number of studies have shown an additive eVect which varies with the type of diabetes and the systolic or diastolic blood pressure (BP). Results-Systolic

Circulatory parameters in the retrobulbar central retinal artery and vein of patients with diabetes and medically treated systemic hypertension

“…There were no significant differences between the groups with and without hypertension, although diabetic patients without hypertension had lower pulsatile ocular blood flow than controls. Arend et al investigated macular circulation in diabetic subjects, and did not detect any significant differences in the circulatory parameters and in the morphology in the macula between the groups with and without systemic hypertension [5]. The authors explained their results partly as a consequence of the antihypertensive therapy of the studied patients.…”

“…A study that investigated pulsatile blood flow in diabetes did not detect any significant differences among hypertensive and normotensive patients [4]. Macular circulation was also non-significantly different between hypertensive and normotensive diabetic patients [5].…”

Do angiographic data support a detailed classification of hypertensive fundus changes?

“…17 Meanwhile, fluorescein angiography has become a widespread diagnostic method for studying retinal microcirculation in vivo. 6,18,19 Quantification of morphologic and haemodynamic parameters has become possible because of improved digital image acquisition and analysis. 20 In patients with mild to moderate hypertensive fundus changes, a significant reduction of PIA and CBV has already been demonstrated, 7 whereby the amount of reduction was found to be independent from the applied antihypertensive drugs.…”

“…3,4 Fluorescein angio-graphy is an established method not only to assess, but also to quantify microvascular changes in a variety of retinal diseases. 5,6 In patients with mild to moderate hypertension, an enlargement of the perifoveal intercapillary areas (PIA) and a reduced capillary blood velocity (CBV) was found. 7 However, for the severe stages of hypertensive retinopathy, the perifoveal microcirculation has not yet been quantified.…”

In vivo dynamic human retinal blood flow imaging using ultra-high-speed spectral domain optical Doppler tomography

“…Accurate knowledge of retinal blood flow dynamics is important in not only the treatment but also understanding the pathophysiology of many diseases, including diabetic retinopathy [1,2] and glaucoma [3]. However, current ocular blood flow measurement techniques such as fluorescein angiography and laser Doppler flowmetry (LDF) have been limited by low resolution and poor depth of penetration [4].…”