MRI - large, regular, asymmetric uterus without leiomyomas, abnormal myometrial SI, thickening of junctional zone (focal or diffuse) and high SI myometrial foci on T1w (haemorrhage) and T2w (endometrial tissue, cystic dilatation, haemorrhage). Diagnosis based on ratio of JZ to M wall thickness of 40%. Cystic adenomyosis shows well-circumscribed cystic lesions w low SI rim on T2w. Also seen - striations from endo into myo.