OC10.02: Inter‐observer variation in diagnosing adenomyosis using two‐ and three‐dimensional transvaginal ultrasound

To investigate inter-observer variation in identification of adenomyosis by two- and three-dimensional (2D and 3D) transvaginal ultrasonography (TVS). Moreover, to evaluate improvement in agreement between experienced and inexperienced sonographers during the time of learning. 103 premenopausal women scheduled for hysterectomy or transcervical resection of the endometrium (TCRE) were enrolled and divided into three groups of patients: A (first 34), B (next 34) and C (last 35). An experienced and an inexperienced sonographer independently performed 2D and 3D TVS examinations. Pattern criteria for adenomyosis were systematically evaluated during 2D TVS. Six months after examination, adenomyosis was again evaluated using stored 3D TVS including junctional zone thickness (JZt:) ≥12mm and irregularity (JZdif: maximum-minimum thickness >5mm) in the first 70 patients. 2D TVS diagnosis of adenomyosis showed substantial agreement (kappa%(CI): 65(50–79)) in 103 patients. Presence of anechoic lacunae and/or myometrial cysts had substantial agreement (kappa%(CI): 63(48–78)), while criteria of heterogeneity, asymmetric corpus myometrium and linear striations had fair agreement. However, there was a steady increase in agreement for presence of the different criteria and the diagnosis of adenomyosis in group A, B and C: ((Kappa%(CI): 47(18–76), 63(37–89) and 82(62–100)). 3D TVS only reached moderate agreement (kappa%(CI): 46(23–68)) in the first 70 patients. Presence of anechoic lacunae and/or myometrial cysts had moderate agreement (kappa%(CI): 38(17–59)), while heterogeneity, asymmetric corpus myometrium and linear striations had slight to fair agreement. There was fair agreement in evaluation of JZt (kappa%(CI): 37(16–59)) and JZdif (kappa%(CI): 33.3(12–55)). In a standardized diagnostic set-up inter-observer variation in diagnosis of adenomyosis was improved to substantial levels after 68 examinations. There was not higher agreement in evaluation of stored 3D TVS, even by addition of JZ measurements.