Artificial intelligence assistance for fetal development: evaluation of an automated software for biometry measurements in the mid-trimester

Abstract

Background: This study presents CUPID, an advanced automated measurement software based on Artificial Intelligence (AI), designed to evaluate nine fetal biometric parameters in the mid-trimester. Our primary objective was to assess and compare the CUPID performance of experienced senior and junior radiologists.

Materials and methods: This prospective cross-sectional study was conducted at Shenzhen University General Hospital between September 2022 and June 2023, and focused on mid-trimester fetuses. All ultrasound images of the six standard planes, that enabled the evaluation of nine biometric measurements, were included to compare the performance of CUPID through subjective and objective assessments.

Results: There were 642 fetuses with a mean (±SD) age of 22 ± 2.82 weeks at enrollment. In the subjective quality assessment, out of 642 images representing nine biometric measurements, 617-635 images (90.65-96.11%) of CUPID caliper placements were determined to be accurately placed and did not require any adjustments. Whereas, for the junior category, 447-691 images (69.63-92.06%) were determined to be accurately placed and did not require any adjustments. In the objective measurement indicators, across all nine biometric parameters and estimated fetal weight (EFW), the intra-class correlation coefficients (ICC) (0.843-0.990) and Pearson correlation coefficients (PCC) (0.765-0.978) between the senior radiologist and CUPID reflected good reliability compared with the ICC (0.306-0.937) and PCC (0.566-0.947) between the senior and junior radiologists. Additionally, the mean absolute error (MAE), percentage error (PE), and average error in days of gestation were lower between the senior and CUPID compared to the difference between the senior and junior radiologists. The specific differences are as follows: MAE (0.36-2.53 mm, 14.67 g) compared to (0.64- 8.13 mm, 38.05 g), PE (0.94-9.38%) compared to (1.58-16.04%), and average error in days (3.99-7.92 days) compared to (4.35-11.06 days). In the time-consuming task, CUPID only takes 0.05-0.07 s to measure nine biometric parameters, while senior and junior radiologists require 4.79-11.68 s and 4.95-13.44 s, respectively.

Conclusions: CUPID has proven to be highly accurate and efficient software for automatically measuring fetal biometry, gestational age, and fetal weight, providing a precise and fast tool for assessing fetal growth and development.

Keywords: Artificial intelligence; Biometry measurement; Fetal growth and development.

Fig. 1

Flowchart summarizing the study design

Fig. 2

Examples of measurement results obtained by Senior, Junior and CUPID for the nine key fetal biometric parameters. BPD, biparietal diameter; HC, head circumference; OFD, occipitofrontal diameter; TCD, transverse cerebellar diameter; PCFW, posterior cranial fossa pool width; LVW, lateral ventricles width; FL, femoral length; HL, humeral length; AC, abdominal circumference (The red arrow indicates the location of the measurement error)

Fig. 3

CUPID’s product interface. BPD, biparietal diameter; HC, head circumference; OFD, occipitofrontal diameter; Th, thalamus; CSP, cavum septum pellucidum; Falx, falx cerebri

Fig. 4

The Pearson correlation coefficient plot shows the agreement between Senior and CUPID, as well as between Senior and Junior, regarding the measurement of nine key fetal biometric parameters and EFW (blue dashed line represents Senior, red line represents CUPID, and blue solid line represents Junior)

Fig. 5

The Bland-Altman plot shows the agreement between Senior and CUPID, as well as between Senior and Junior, regarding the measurement of nine key fetal biometric parameters and EFW (red dots: senior and CUPID, blue dots: Senior and Junior)

Fig. 6

Trend curve of estimated gestational age error in days measured by CUPID, Senior, and Junior