title: MRI of the female pelvis: a possible pitfall in the differentiation of haemorrhagic vs. fatty lesions using fat saturated sequences with inversion recovery.
abstract: The use of fat-saturated techniques should be an integral part of the work-up of any T1-hyperintense structure in the female pelvis for tissue characterization and for differentiation of a fat-containing ovarian mature teratoma from a haemorrhagic lesion. Two cases with haematocolpos and haematometra are presented, respectively. The haemorrhagic content showed high signal both on T1- and T2-weighted images, whereas an unexpected signal decrease in the fat-saturated T2-weighted inversion-recovery sequence was encountered. This unspecific suppression of signal in tissues with similar T1 relaxation times as fat can lead to a diagnostic pitfall both in T1- and T2-weighted STIR pulse sequences. Furthermore, a loss of signal on T2-weighting may also be due to the phenomenon of "T2-shading" in T1-bright ovarian endometrioma. Therefore, the fat-specific spectral fat-saturation of T1-weighted images is strongly recommended for tissue characterization in gynaecological disease.
authors.affiliation: Department of Radiology, Kantonsspital Baden, Baden, Switzerland.
authors.forename: Johannes M
authors.initials: JM
authors.lastname: Froehlich
authors.forename: Thierry
authors.initials: T
authors.lastname: Metens
authors.forename: Bianka
authors.initials: B
authors.lastname: Chilla
authors.forename: Nik
authors.initials: N
authors.lastname: Hauser
authors.forename: Michael K
authors.initials: MK
authors.lastname: Hohl
authors.forename: Rahel A
authors.initials: RA
authors.lastname: Kubik-Huch
mesh_terms: D000293:Adolescent; D000328:Adult; D003937:Diagnosis, Differential; D005260:Female; D006399:Hematocolpos / Q000175:diagnosis* / Q000601:surgery; D006409:Hematometra / Q000175:diagnosis*; D006801:Humans; D007044:Hysterectomy; D008279:Magnetic Resonance Imaging / Q000379:methods*; D013724:Teratoma / Q000175:diagnosis; D014594:Uterine Neoplasms / Q000175:diagnosis