Diffusion-weighted imaging of ovarian torsion: usefulness of apparent diffusion coefficient (ADC) values for the detection of hemorrhagic infarction.
OBJECTIVE
We undertook this study to evaluate the need for diffusion-weighted (DW) magnetic resonance (MR) imaging in detecting hemorrhagic infarction following ovarian torsion.


METHODS
The study included 14 consecutive patients aged 12 to 74 years (average age, 36 years) with surgical confirmation of ovarian torsion who underwent 1.5-tesla MR imaging. Pathologically, hemorrhagic infarction was found in 7 patients. We retrospectively reviewed signal intensity on T1-, T2-, and diffusion-weighted images and apparent diffusion coefficients (ADCs) in swollen ovarian stroma.


RESULTS
Fallopian tube thickening was seen in all patients. In patients with ovarian cystic lesion, maximum cyst wall thickness was significantly higher in patients with hemorrhagic infarction (mean, 13.5 ± 4.1 mm) than those without (mean, 5.0 ± 1.0 mm) (P < .05). Signal intensity did not differ significantly on T1-weighted, T2-weighted, and DW images between patients with and without hemorrhagic infarction. ADCs were significantly lower in patients with hemorrhagic infarction (1.20 ± 0.50 [× 10(-3) mm(2)/s]) than those without (2.04 ± 0.26 [× 10(-3) mm(2)/s]) (P < .01). With an ADC threshold of 1.80 [× 10(-3) mm(2)/s], sensitivity for hemorrhagic infarction was 0.88 (7 of 8), and specificity was 1.00 (6 of 6).


CONCLUSIONS
ADC measurements were useful for detecting hemorrhagic infarction in patients with ovarian torsion.
Department of Radiology, Gifu University School of Medicine.
Hiroki
H
Kato
Masayuki
M
Kanematsu
Mariko
M
Uchiyama
Ryuichiro
R
Yano
Tatsuro
T
Furui
Ken-ichirou
K
Morishige
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006470:Hemorrhage / Q000175:diagnosis* / Q000209:etiology; D006801:Humans; D007238:Infarction / Q000175:diagnosis* / Q000209:etiology; D008875:Middle Aged; D010049:Ovarian Diseases / Q000175:diagnosis* / Q000209:etiology; D012189:Retrospective Studies; D014102:Torsion Abnormality / Q000150:complications / Q000175:diagnosis*