High-resolution imaging diagnosis of human fetal membrane by three-dimensional optical coherence tomography

Microscopic chorionic pseudocyst (MCP) arising in the chorion leave of the human fetal membrane (FM) is a clinical precursor for preeclampsia which may progress to fatal medical conditions (e.g., abortion) if left untreated. To examine the utility of three-dimensional (3D) optical coherence tomography (OCT) for noninvasive delineation of the morphology of human fetal membranes and early clinical detection of MCP, 60 human FM specimens were acquired from 10 different subjects undergoing term cesarean delivery for an ex vivo feasibility study. Our results showed that OCT was able to identify the four-layer architectures of human FMs consisting of high-scattering decidua vera (DV, average thickness d(DV) ≈ 92±38 μm), low-scattering chorion and trophoblast (CT, d(CT) ≈ 150±67 μm), high-scattering subepithelial amnion (A, d(A) ≈ 95±36 μm), and low-scattering epithelium (E, d(E) ≈ 29±8 μm). Importantly, 3D OCT was able to instantaneously detect MCPs (low scattering due to edema, fluid buildup, vasodilatation) and track (staging) their thicknesses d(MCP) ranging from 24 to 615 μm. It was also shown that high-frequency ultrasound was able to compliment OCT for detecting more advanced thicker MCPs (e.g., d(MCP)>615 μm) because of its increased imaging depth.