Assessment of Cesarean hysterotomy scar in non-pregnant women: reliability of transvaginal sonography with and without contrast enhancement

Abstract

Objectives: To determine intra- and interobserver reliability of evaluating the appearance and measurement of Cesarean hysterotomy scars using transvaginal ultrasound (TVS), with and without saline contrast sonohysterography (SCSH), in non-pregnant women.

Methods: Fifty-six women with one previous Cesarean delivery were examined by TVS, with and without contrast enhancement, 6-9 months after the Cesarean delivery. Two observers, blinded to their own and each other's measurements, evaluated the appearance of the hysterotomy scar and measured the myometrial thickness adjacent to the scar or scar defect (MTS). If a scar defect was noted, the remaining myometrial thickness over the defect (RMT) was measured. A scar defect was defined as large if RMT was ≤ 2.2 mm on conventional TVS and ≤ 2.5 mm when SCSH was performed. Intra- and interobserver reliability of conventional TVS and SCSH were assessed.

Results: Intraobserver reliability was good, with intraclass correlation coefficients (ICCs) of ≥ 0.97 for measurements of MTS and RMT on conventional TVS and SCSH. Interobserver ICCs for measurements obtained on SCSH were 0.85 (95% CI, 0.76-0.91) for MTS and 0.96 (95% CI, 0.93-0.98) for RMT, compared with 0.82 (95% CI, 0.72-0.89) for MTS and 0.87 (95% CI, 0.68-0.95) for RMT measured on conventional TVS. The kappa coefficient for measurements obtained on SCSH was 0.92, compared with 0.85 for conventional TVS. Intermethod ICC was 0.86 (95% CI, 0.78-0.92) for measurement of MTS and 0.89 (95% CI, 0.78-0.95) for measurement of RMT, with a kappa coefficient of 0.57.

Conclusions: Measurement of RMT using SCSH is a reliable method for assessing Cesarean hysterotomy scars in non-pregnant women and can be used in clinical practice. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Keywords: Cesarean scar defect; intermethod agreement; interobserver agreement; intraobserver agreement; reliability; saline contrast sonohysterography; ultrasonography.