An observational study in Diabetic Retinopathy (DR), Cardiopulmonary Bypass and Retinal Vascular Diseases, sponsored by Samsun University. Completed at 1 site in Turkey (Türkiye). Open to participants aged 30 Years to 70 Years. Per ClinicalTrials.gov, last updated 2025-06-27.
Sponsored by Samsun University · Observational
This prospective observational study investigates the impact of pulsatile versus non-pulsatile cardiopulmonary bypass (CPB) flow on choroidal circulation in diabetic and non-diabetic patients undergoing elective coronary artery bypass grafting (CABG). A total of 104 patients aged 30 to 70 years will be included, with balanced distribution between diabetic and non-diabetic groups. Optical coherence tomography angiography (OCTA) will be performed preoperatively and at 1 month postoperatively to assess changes in choroidal vascularity. The primary objective is to determine whether the type of CPB flow affects choroidal microcirculation, particularly in diabetic patients. The findings may support more individualized perfusion strategies in patients at risk of ocular microvascular impairment.
This prospective observational study aims to investigate the effects of pulsatile and non-pulsatile cardiopulmonary bypass (CPB) flow types on choroidal and retinal microcirculation in diabetic and non-diabetic patients undergoing elective coronary artery bypass graft (CABG) surgery. Previous literature suggests that pulsatile perfusion may enhance end-organ perfusion, but data on ocular microvascular circulation remain scarce, especially in diabetic patients.
A total of 104 patients between the ages of 30 and 70 will be enrolled and divided into four groups based on diabetes status and CPB flow type. Optical coherence tomography angiography (OCTA) will be performed preoperatively and at 1 month postoperatively to measure the choroidal vascularity index (CVI) and other retinal microvascular parameters.The primary outcome is the change in CVI between baseline and 1-month follow-up. Secondary outcomes include retinal microvascular changes and comparative analyses between diabetic and non-diabetic groups.By evaluating the relationship between CPB flow type and ocular perfusion, particularly in patients with longstanding diabetes, this study may provide evidence to support individualized CPB strategies to minimize ocular microvascular compromise in cardiac surgery.
772 studies on the registry are indexed under Diabetic Retinopathy; 138 are open to participants now.
This study's enrollment of 102 is below the median of 154 across 264 observational studies indexed under Diabetic Retinopathy.
Browse Diabetic Retinopathy studies →Samsun University is the lead sponsor of 81 studies on the registry; 21 are open to participants now.
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Patients scheduled for elective coronary artery bypass grafting, including diabetic and non-diabetic individuals, recruited at a single center (Samsun Training and Research Hospital).
Exclusion Criteria:
Diabetic patients undergoing elective coronary artery bypass grafting (CABG) with pulsatile cardiopulmonary bypass (CPB) flow. Preoperative and postoperative 1st month OCTA measurements will be taken.
Diabetic patients undergoing elective CABG with non-pulsatile CPB flow. OCTA measurements preoperatively and at 1 month postoperatively.
Non-diabetic patients undergoing elective CABG with pulsatile CPB flow. OCTA measurements preoperatively and at 1 month postoperatively.
Non-diabetic patients undergoing elective CABG with non-pulsatile CPB flow. OCTA measurements preoperatively and at 1 month postoperatively.
Change in Choroidal Vascularity Index (CVI) from Baseline to 1-Month Postoperative
CVI will be calculated from OCTA images preoperatively and 1 month postoperatively. Mean change in CVI will be compared between pulsatile and non-pulsatile CPB groups.
Time frame: 1 month after surgery
Change in Retinal Vascular Density (RVD)
RVD will be assessed by OCTA and measured as vessel density (%) at baseline and 1-month post-op, compared between study groups.
Time frame: 1 month after surgery
Change in Foveal Avascular Zone (FAZ) Area
FAZ area will be measured preoperatively and 1 month postoperatively using OCTA, and compared across study groups.
Time frame: 1 month after surgery
Comparison of CVI Change Between Diabetic and Non-Diabetic Patients
Subgroup analysis of CVI change will be performed to assess whether diabetes status affects choroidal perfusion response to CPB flow type.
Time frame: 1 month after surgery
This study is completed, as verified in Jun 2025. You cannot join it, but the record below documents what was studied.
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Samsun University