Evaluation of an objective method of image assessment for first‐trimester nasal bone

Abstract

Objective To evaluate the degree of agreement in firsttrimester nasal bone assessment in a group of sonographers before and after training, using a semi-quantitative scoring system. (ICC, 0.929). Methods ConclusionThe proposed scoring system can be used to improve consistency and reliability in first-trimester nasalbone assessment.

Image-scoring system for crown-rump length measurement

“…Similar findings have been demonstrated in second‐trimester fetal biometry. Studies on NT and nasal bone measurements have also found objective assessment to be more reproducible than is subjective judgment.…”

“…All images were evaluated both subjectively and objectively by two independent reviewers (A and B). This was done using similar methodology to that used for studies assessing second‐trimester biometry and first‐trimester NT and nasal bone measurements. For subjective evaluation, the reviewers were required to rate an image as either acceptable or unacceptable when the image was presented to them.…”

“…The use of image scoring for fetal biometry in the second trimester has been evaluated and found to be both feasible and reproducible. Other studies have also evaluated quality control and image‐scoring systems for NT and nasal bone measurements in the first trimester as part of trisomy 21 screening. The reliability of these image‐scoring systems has seen their validation and use in research, quality control and clinical audits.…”

Quality control of ultrasound for fetal biometry: results from the INTERGROWTH‐21st Project

“…For one sonographer (a), 3% of 365 triplicate measurements were above 97.5 th centile; for the other (b), 17% of 186 measurements were above accepted threshold, set at 10%, and retraining was undertaken. quality 7,10,23,24 , and secondly, visual assessment of ultrasound images was based on an objective criterion-based scoring system, which has been shown to be significantly more reproducible than subjective methods 8,25,26 . In Salomon et al's 8 original description of this process, high reproducibility levels for the image scoring method were demonstrated (kappa between 0.60 and 0.98); despite undertaking QC in a blinded fashion, the results from our study were even better.…”

Validation of First Trimester Screening for Trisomy 21 in Singapore with Reference to Performance of Nasal Bone

“…This shows that nasal bone is an essential marker for improved screening efficacy. We have recently demonstrated good consistency in its assessment amongst our sonographers and that further improvement can be achieved with appropriate training [15]. …”