Abstract
BACKGROUND: Intrauterine adhesions (IUA), a common complication following repeated uterine procedures, lead to reduced endometrial perfusion due to vascular injury in the endometrial basal layer, contributing significantly to infertility. Accurate assessment of endometrial perfusion is therefore crucial for improving fertility outcomes. Contrast-enhanced ultrasonography (CEUS) is a well-established imaging technique for dynamic and quantitative perfusion assessment. Arrival time parametric imaging (ATPI) is a CEUS-based technique that generates color-coded maps from microbubble perfusion data, providing a visual and quantitative display of perfusion intensity and temporal distribution. This study aimed to investigate the value of CEUS-based ATPI for the evaluation of endometrial perfusion in patients with IUA. METHODS: This retrospective study included cases showing normal uterine morphology (normal uterine group) and patients with IUA who underwent hysteroscopy examinations at The Third Affiliated Hospital of Guangzhou Medical University between December 2020 and October 2023. Qualitative indicators of ATPI performed before hysteroscopy, including muscle layer color classification (Type A and B) and endometrial color classification (Type 1 and 2), quantitative indicators comprising average arrival time (AAT), earliest arrival time (EAT), latest arrival time (LAT), and the overall arrival time difference (△T) of the endometrium were compared. Correlation analysis between ATPI quantitative indicators and American Fertility Society (AFS) score in hysteroscopy was also performed. RESULTS: A total of 92 subjects were enrolled in this study, including 74 in the IUA group and 18 in the normal uterine group. IUA patients were divided into mild adhesion (n=3), moderate adhesion (n=57), and severe adhesion (n=14) subgroups according to AFS score. The proportions of Type B muscle layer and Type 2 endometrium accounted for a significantly higher proportion in the IUA group compared to the normal uterine group [70.3% (52/74) vs. 33.3% (6/18) and 68.9% (51/74) vs. 38.9% (7/18), respectively; P=0.004, P=0.018]. LAT and △T were both higher in the IUA group compared to the normal uterine group (18.39±4.97 vs. 16.49±2.67, P=0.031; 15.60±4.75 vs. 13.90±2.43, P=0.037). AAT and EAT were higher in the severe subgroup than in the moderate subgroup (9.20±1.39 vs. 7.80±1.96, P=0.047; 3.31±0.62 vs. 2.66±0.85, P=0.035). A positive correlation between EAT and AFS scores was also observed (r=0.230, P<0.05). CONCLUSIONS: ATPI might visually display the perfusion status of endometrium adhesions. AAT and EAT can serve as quantitative indicators of uterine adhesion progression. In addition, EAT was positively correlated with AFS score grouping, indicating that it could effectively detect severe IUA and provide more comprehensive diagnostic information for clinical diagnosis and treatment.