Shear wave elastography for detecting placental abnormalities in type 1
and type 2 diabetes: a systematic review and meta-analysis.
Abstract
Background: Diabetes prior to conception may cause pregnancy
complications through disruptions of placental function. Objectives/Key
Questions: 1) To describe placental changes in women with pre-existing
diabetes. 2) To determine if elastography can detect in-vivo placental
changes? Search Strategy: PubMed, Embase, Medline, Cochrane database
searches of English language reports published until July 2020.
Selection Criteria: Question 1: Any study describing placental
histopathology in women with known diabetes. Question 2: Any study using
elastography to report in-vivo placental stiffness values. Data
Collection and Analysis: For Key Question 1: we grouped placental
pathologies using Amsterdam International Consensus Group definitions.
For Key Question 2: we conducted a meta-analysis of placental stiffness
scores reported in metres per second (m/s) or kilopascals (kPa). Main
Results: Cumulative data from 14 studies showed no placental
histopathology features pathognomonic for diabetes. Pooled analysis of
14 studies included 478 “high risk pregnancies” and 828
control/healthy pregnancies. Only one study reported stiffness scores
for placentas of women with pre-existing diabetes (N < 10
women). Maternal-derived pathologies resulted in higher placental
stiffness with mean difference 4.5kPa (95% CI 3.16, 5.87) compared to
control / healthy pregnancies. Fetal-derived pathologies resulted in
higher placental stiffness with mean difference of 6.5kPa (95% CI 1.08,
11.86) compared to control / healthy pregnancies. Conclusions: Shear
Wave Elastography may provide in-vivo approximation of placental
histopathology. Further studies in women with pre-existing diabetes may
confirm this. Funding: primary author (AG) receives Western Sydney
University Postgraduate Research Scholarship (Ainsworth Trust) and
Australian Federal Government Research Training Program (RTP) Fees
Offset.