title: Usefulness of T2 star-weighted imaging in ovarian cysts and tumors.
abstract: OBJECTIVE
  The aim of this study was to investigate the prevalence of hypointensity on T2 star-weighted imaging (T2*WI), which is useful for detecting hemosiderin, in endometriomas and other ovarian tumors. The efficacy of detecting adhesions around ovarian tumors was also investigated.
  
  
  METHODS
  Pelvic magnetic resonance (MR) examinations, including T2*WI, were carried out. The inclusion criteria were female patients with ovarian surgical treatments. One hundred seventeen patients with a total of 147 lesions were enrolled. Two radiologists retrospectively evaluated MR imaging (MRI) to predict ovarian pathology and the presence of adhesions. T2*WI hypointensity of the inside and outside along ovarian cysts/tumors was utilized to predict pathological diagnoses and the presence of adhesions, respectively. The kappa scores were calculated to measure interobserver agreement on MRI findings. The MRI interpretations were compared with the results of pathological investigation and surgical observations.
  
  
  RESULTS
  Hypointensity inside along the cyst walls on T2*WI was observed in 100 out of 106 lesions of endometriomas (94.3%), and three out of 41 non-endometrial ovarian cysts/tumors (7.3%). Four different patterns of T2*WI were observed in ovarian cysts/tumors. The kappa score regarding T2*WI hypointensity inside along the cyst walls was 0.633. Using conventional routine pelvic MRI, the sensitivity for detecting adhesions around ovarian cysts was 84.5%. By adding T2*WI, the sensitivity improved to 91.4% (P < 0.01). With conventional methods to predict adhesions, the kappa score was 0.660. After adding T2*WI to the conventional methods, the kappa score was 0.767.
  
  
  CONCLUSIONS
  Hypointensity on T2*WI was observed frequently in endometrioma. T2*WI also improved the sensitivity for detecting adhesions around ovarian cysts/tumors.
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokyo, Tokyo, Japan.
authors.forename: Nozomi
authors.initials: N
authors.lastname: Takahashi
authors.affiliation: Department of Obstetrics and Gynecology, The University of Toyama, Toyama, Japan. oyoshino624@hotmail.co.jp.
authors.forename: Osamu
authors.initials: O
authors.lastname: Yoshino
authors.affiliation: Department of Radiology, The University of Tokyo, Tokyo, Japan.
authors.forename: Eriko
authors.initials: E
authors.lastname: Maeda
authors.affiliation: Department of Radiology, The University of Tokyo, Tokyo, Japan.
authors.forename: Shotaro
authors.initials: S
authors.lastname: Naganawa
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokyo, Tokyo, Japan.
authors.forename: Miyuki
authors.initials: M
authors.lastname: Harada
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokyo, Tokyo, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Koga
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokyo, Tokyo, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Hiraike
authors.affiliation: Medical Satellite Yaesu Clinic, Tokyo, Japan.
authors.forename: Masanobu
authors.initials: M
authors.lastname: Nakamura
authors.affiliation: Medical Satellite Yaesu Clinic, Tokyo, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Tabuchi
authors.affiliation: Department of Radiology, The University of Juntendo, Tokyo, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Hori
authors.affiliation: Department of Obstetrics and Gynecology, The University of Toyama, Toyama, Japan.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Saito
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokyo, Tokyo, Japan.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Fujii
authors.affiliation: Department of Obstetrics and Gynecology, The University of Tokyo, Tokyo, Japan.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Osuga
mesh_terms: D000328:Adult; D000368:Aged; D004715:Endometriosis / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006485:Hemosiderin / Q000032:analysis*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D010388:Pelvis / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D006485:Hemosiderin
keywords: T2 star-weighted magnetic resonance imaging; adhesion; endometrioma; endometriosis; mucinous cystadenoma