The myometrial-cervical ratio: Can a simple sonographic measurement improve diagnosis of adenomyosis in a regional setting?

Abstract

Adenomyosis is histologically defined by the presence of endometrial glands and stroma in the myometrium. Ultrasound findings of adenomyosis are being redefined to better diagnose adenomyosis pre-operatively. A single-centre retrospective study was performed at a regional hospital. The myometrial-cervical ratio was calculated on pre-operative ultrasounds, and histopathology reviewed for each case. Logistic regression was used to estimate the association between the myometrial-cervical ratio and adenomyosis confirmed on histopathology, and the area under the receiver operating characteristic curve was calculated. Comparisons were performed based on the presence of fibroids on ultrasound. Complete data were available for 136 benign hysterectomies between 1 January 2015 and 31 December 2020. When the myometrial-cervical ratio was treated as a continuous variable in a logistic regression of adenomyosis on histopathology, there was no statistical evidence (χ2(1) < 0.01, p = 0.98) of an association. When cases including fibroids in the myometrial-cervical ratio were excluded, there was a non-significant association between myometrial-cervical ratio and adenomyosis on histopathology (odds ratio = 3.435, 95% confidence interval = 0.964, 12.235; χ2(1) = 3.62, p = 0.057); area under the receiver operating characteristic = 0.637 (95% confidence interval = 0.504, 0.770). The optimal myometrial-cervical ratio cutpoint was 1.875 (95% confidence interval = 1.698, 2.051), which achieved 71.43% sensitivity and 60.00% specificity. There was strong statistical evidence (χ2(1) = 9.02, p = 0.003) that the myometrial-cervical ratio outperformed standard pre-operative ultrasound identification of adenomyosis. While accuracy remains suboptimal, the myometrial-cervical ratio outperformed standard ultrasound diagnostic features of adenomyosis in a regional setting. The myometrial-cervical ratio may offer a simple imaging measurement for adenomyosis in inexperienced hands when fibroids are absent.