<p>Preeclampsia is associated with systemic endothelial dysfunction and microvascular injury, but direct noninvasive evidence of retinal wall-to-lumen structural alterations remains limited. In this cross-sectional study, 88 women were enrolled, including 28 with preeclampsia, 30 healthy pregnant controls, and 30 healthy non-pregnant controls. Retinal vascular cross-sectional images obtained by optical coherence tomography were analyzed using an automated PKSEA-Net-based workflow to quantify arterial and venous outer diameters, lumen diameters, and derived wall metrics. Compared with controls, preeclampsia was characterized mainly by a narrower retinal arterial lumen diameter and a higher arterial wall-to-lumen ratio. After adjustment for age and axial length, preeclampsia remained associated with lower retinal arterial lumen diameter and higher arterial wall-to-lumen ratio than healthy non-pregnant controls. Among pregnant participants, further adjustment for gestational age showed that preeclampsia was associated with lower arterial lumen diameter, higher arterial wall-to-lumen ratio, and lower venous lumen diameter than healthy pregnant controls. Higher mean arterial pressure and greater proteinuria burden were independently associated with less favorable retinal arteriolar structural parameters. These findings suggest arteriole-dominant retinal wall-to-lumen structural abnormalities in women with preeclampsia. Automated optical coherence tomography-based quantification may provide a noninvasive approach for characterizing hypertensive microcirculatory injury in pregnancy.</p><p></p>