Background: Endometrioma is a common manifestation of endometriosis that can be difficult to diagnose with conventional magnetic resonance imaging (MRI). Susceptibility-weighted imaging (SWI) may be more sensitive than conventional MRI in the detection of chronic, local hemorrhagic disease.
Purpose: To investigate whether signal voids in SWI sequences could be used in the preoperative diagnosis of endometrioma.
Material and methods: This retrospective study included consecutive female patients with clinically suspected endometrioma. All patients underwent pelvic 3-T MRI (T1- and T2-weighted) and SWI within two weeks before laparoscopy. Two experienced radiologists blinded to the histopathologic/clinical diagnoses interpreted the images together, and any disagreements were resolved by consensus.
Results: The final analysis included 73 patients: 46 patients (mean age=37 years; age range=22-68 years) with 85 endometrioma lesions and 27 patients (mean age=34 years; age range=15-68 years) with 34 non-endometrioid cystic lesions (18 hemorrhagic corpus luteal cysts, three simple cysts, three mucinous cystadenomas, two mature teratomas, and one endometrioid cyst with corpus luteum rupture/hemorrhage). The presenting symptoms for patients with endometrioma were chronic pelvic pain (44.6%), dysmenorrhea (31.9%), infertility (12.8%), dyspareunia (6.4%), and menstrual irregularity (4.3%). MRI identified all 119 lesions observed laparoscopically. SWI visualized punctate or curvilinear signal voids along the cyst wall or within the lesion in 67 of 85 endometriomas (78.8%) and only 3 of 31 non-endometrioid cysts (8.8%).
Conclusion: The use of SWI to look for signal voids in the cyst wall or within the lesion could facilitate the preoperative diagnosis of endometrioma.
Keywords: Endometrioma; female pelvis; magnetic resonance imaging; susceptibility-weighted imaging.