RECENT research has uncovered significant correlations between the severity of internal carotid artery (ICA) stenosis and retinal parameters in patients with proliferative diabetic retinopathy (PDR), shedding light on potential risk factors.
“Understanding the intricate interplay between PDR and ICA stenosis is essential due to their potential bidirectional influence on each other,” wrote Chae Yoon Lee and colleagues, Department of Ophthalmology, Maryknoll Hospital, Busan, Korea. Conducted as a retrospective analysis, the research involved 68 patients (136 eyes) diagnosed with bilateral PDR between January 1, 2017–December 31, 2021 (mean age: 62.55 years).
Carotid artery stenosis (CAS) was evaluated utilising neck computed tomography angiography and carotid duplex ultrasound, categorising stenosis into normal (<50%; n = 51) and mild or above (50%; n=17), according to the North American Symptomatic Carotid Endarterectomy Trial (NASCET) criteria. Retinal parameters were measured using optical coherence tomography, and optical coherence tomography angiography.
The results of the study unveiled significant differences between the two groups in various retinal parameters. Notably, patients with more severe ICA stenosis exhibited distinct retinal changes, including alterations in total vessel density (VD; 13.73 versus 11.53; P=0.003), foveal avascular zone area (0.53 versus 0.56; P=0.002), total retinal nerve fibre layer (RNFL) thickness (97.87 versus 95.04; P =0 .013), and temporal RNFL thickness (82.46 versus 71.75; P=0.019). Furthermore, parameters such as hyperlipidaemia, total cholesterol levels, and intraocular pressure also displayed significant differences.
However, certain parameters like subfoveal choroidal thickness, central VD, average ganglion cell-inner plexiform layer thickness; and superior, nasal, and inferior RNFL thickness, did not exhibit notable differences between the two groups.
In conclusion, the findings underscore the importance of assessing carotid artery health in patients with PDR. The observed retinal changes, including an enlarged foveal avascular zone area, decreased total VD, and thinner temporal RNFL, emphasise the necessity for carotid artery evaluation as part of clinical management for patients with PDR. These insights have significant implications for clinical practice, highlighting the imperative of comprehensive care for individuals with diabetic retinopathy.
Reference:
Lee CY et al. Risk factors of internal carotid artery stenosis in patients with proliferative diabetic retinopathy: an analysis using optical coherence tomography and optical coherence tomography angiography. BMC Ophthalmol. 2024;24:156.
