[Diagnostic value of magnetic resonance imaging in special-site ectopic pregnancy]

To explore the magnetic resonance imaging (MRI) features and diagnostic value of special-site ectopic pregnancy.

The MRI features of special-site ectopic pregnancy on 39 pathologically confirmed cases were retrospectively analyzed. All cases received ultrasonic inspection, MRI plain scan and 11 cases underwent enhanced scan.

In 39 cases, there were 3 cases of interstitial tubal pregnancy (n = 3), cornual pregnancy (n = 8) and uterine scar pregnancy (n = 28). The accuracy rates of location and diagnosis were 94.9% and 82.1% respectively. And they were both higher than the rates of ultrasound. They were classified into two groups by clinical outcomes:pregnancy and miscarriage. In 22 cases of pregnancy, there were sac in sac (n = 9) and complete fertilized egg (n = 13). In 17 cases of miscarriage, there were irregular honeycomb (n = 7), ring (n = 6) and mass (n = 4). Among 11 enhanced cases, there were significant enhancement (n = 4), flake or cord-like enhancement (n = 5), a little strengthen on edge (n = 1) and no enhancement (n = 1). The group had intrauterine decidual tissue hyperplasia (n = 22), ovarian cyst (n = 8), pelvic fluid (n = 6), adenomyosis (n = 3), fibroid (n = 2), endometriosis in pelvic and abdominal wall scar area (n = 1) and mild hydrops in right kidney and ureter (n = 1).

The MRI features of special-site ectopic pregnancy are characteristic and important for clinical treatment.