From: The relationship between carotid disease and retinopathy in diabetes: a systematic review
First author | Diabetic retinopathy variable/s | Diabetic retinopathy assessment | Carotid disease variable/s | Carotid disease assessment |
---|---|---|---|---|
Cardoso [23] | New or worsening DR | DR graded as none, mild NPDR, moderate NPDR, severe NPDR or PDR by ophthalmologist at annual review. Worsening defined as worse by at least two grades (e.g. from mild to severe NPDR) | IMT of ICA, BIF and CCA Plaque score Number of plaques | Mean of 3 IMT measurements used, IMT measured according to Mannheim consensus Extracranial carotid artery plaque score assigned for each segment of ICA, CCA and BIF and highest grade assigned; 0: no plaque, 1: one small plaque, stenosis < 30%, 2: one medium plaque, 30–49% stenosis or multiple small plaques, 3: one large plaque, 50–99% stenosis or multiple plaques with at least one medium plaque, 4: 100% occlusion Single vascular radiologist performed ultrasound, good intra-observer test–retest reliability |
Hjelmgren [32] | Any | Medical records from all eye clinics in the area | Stenosis > 50% | Greater stenosis from left or right artery used |
Ichinohasama [8] | Mild NPDR versus no DR | Right eye assessed by ophthalmologist, according to ETDRS protocol | CCA IMT | Maximum measurement of right CCA IMT |
Carbonell [7] | None, mild or advanced (moderate NPDR or worse) | Examination by ophthalmologist, according to ETDRS protocol | Plaque | Plaque was defined according to the Mannheim consensus Single sonographer at each study site performed ultrasound |
Liu [34] | Any | Retinal images graded by ophthalmologist according to International Clinical Diabetic Retinopathy Disease Severity Scale | CCA IMT > 1 mm Plaque Subclinical atherosclerosis | Maximum CCA IMT value of left or right artery used, IMT was measured 1.5 cm proximal to the bifurcation, elevated CCA IMT defined as > 1 mm Plaque was classified as focal increase in thickness more than 0.5 mm or 50% of surrounding IMT Subclinical atherosclerosis was defined as CCA IMT > 1 mm and/or presence of carotid plaque Single sonographer performed ultrasound |
Alonso [28] | Any and mild NPDR, moderate NPDR or severe NPDR or PDR | Multi-field stereoscopic retinal images and ophthalmologist examination | IMT of ICA, BIF and CCA Plaque | Semiautomatic software provided data for mean and mean-maximum IMT from segments of ICA, BIF and CCA. Values from the left and right arteries were averaged Plaque was defined according to the Mannheim consensus Single sonographer performed ultrasound |
Jung [27] | Any | Examination by ophthalmologist | CCA IMT ≥ 1 mm, Plaques > 2 | CCA IMT measured 1 cm proximal to bulb on left and right, mean of these were used Protrusions > 100% defined as plaque. Plaques were categorised into n ≤ 2 and n > 2 plaques |
Cardoso [29] | Any | Examination by ophthalmologist | IMT of CCA, BIF, ICA Plaque score ≤ 2 or > 2 | Mean of 3 IMT measurements used. IMT measured according to Mannheim consensus Extracranial carotid artery plaque score assigned for each segment of ICA, CCA and BIF and highest grade assigned; 0: no plaque, 1: one small plaque, stenosis < 30%, 2: one medium, plaque 30–49% stenosis or multiple small plaques, 3: one large plaque, 50–99% stenosis or multiple plaques with at least one medium plaque, 4: 100% occlusion Single vascular radiologist performed ultrasound, good intra-observer test–retest reliability |
Yun [10] | Any | Retinal images graded according to ETDRS protocol | CCA IMT Plaque | CCA IMT measured by software at thickest point ~ 1 cm from bulb, analysed in tertiles Plaque defined as protrusions into lumen that were 100% thicker than surrounding area Physicians performed ultrasound |
Son [10] | Any | Two-field retinal images and ophthalmologist examination | CCA IMT ≤ 0.9 mm and no plaque compared to CCA IMT > 0.9 mm ± carotid plaque | IMT measured bilaterally 5–10 mm proximal to bulb, 3 measurements done at site of greatest thickness and 10 mm proximal and distal to this point, highest mean CCA IMT used Plaque was a focal increase of ≥ 0.5 mm or ≥ 50% of surrounding IMT Single sonographer performed ultrasound |
Araszkiewicz [30] | Any | Two-field retinal images and ophthalmologist examination according to American Academy of Ophthalmology | CCA IMT | Right CCA IMT measured and automatically calculated with software program—Carotid Analyzer for Research (CAD 5) |
Lacroix [33] | Any | Examination by ophthalmologist | no atherosclerotic lesion or stenosis < 60% or stenosis ≥ 60% | Stenosis was considered ≥ 60% when the maximal velocity within the lesion was > 2.6 m/s and the end-diastolic velocity > 0.7 m/s Performed by experienced vascular physicians |
Distiller [31] | Any | Retinal images assessed | CCA IMT Plaque IMT risk (low, medium or high) | CCA IMT measured > 1 cm proximal to flow divider, mean of left and right used Plaque defined as localised thickening of wall of ≥ 1.5 mm IMT risk: low < 0.6 mm, medium 0.6–0.8, high > 0.8 and/or plaque Two sonographers, intra-observer & inter-observer variability 3.1% and 3.9% |
Rema [9] | Any | Four-field retinal images graded according to ETDRS protocol by two graders, a third grader made final decision if discrepancy | IMT of CCA, BIF, ICA | Mean of six IMT measurements of right ICA, CCA and BIF All scans were quality controlled by a central laboratory in Canada |