The ultrasound (US) features of struma ovarii are nonspeciﬁc, but a heterogeneous, predominantly solid mass may be seen. US demonstrates a complex appearance with multiple cystic and solid areas, ﬁndings that reﬂect the gross pathologic appearance of the tumor.
Magnetic resonance imaging ﬁndings may be more characteristic: The cystic spaces demonstrate both high and low signal intensity on T1- and T2-weighted images. Some of the cystic spaces may demonstrate low signal intensity on both T1- and T2-weighted images due to the thick, gelatinous colloid of the struma. No fat is evident in these lesions.
^Kim D, Cho HC, Park JW et al. (March 2009). "Struma ovarii and peritoneal strumosis with thyrotoxicosis". Thyroid19 (3): 305–8. doi:10.1089/thy.2008.0307. PMID19265502.CS1 maint: Explicit use of et al. (link)