Polycystic ovary syndrome: Pelvic MRI as alternative to pelvic ultrasound for the diagnosis in overweight and obese adolescent girls

Abstract Background Polycystic ovary syndrome (PCOS) is a common reproductive endocrinopathy in women of childbearing age, affecting 5–15% women in this age group. Suggestive cardinal features comprise hyperandrogenism, ovulatory dysfunction and/or polycystic ovary appearance. The gold standard radiological tool is the pelvic ultrasound (PUS) whose yield may be limited in overweight and obese adolescent girls. Objective and hypotheses To evaluate the contribution of pelvic MRI to the diagnosis of PCOS in a specific group of virginal overweight and obese adolescent girls. Method Eight adolescent girls seen for menstrual irregularitiesor amenorrhea, with features of hyperandrogenismwere biochemically screened (LH, FSH, testosterone, S-DHEA, delta- 4 androstenedione, 17 (OH) P, SHBG, TSH, free T4, prolactin and lipid profile, fasting blood sugarand HOMA-IR and HOMA-B). Each had PUS and/or pelvic MRI (PMRI) performed. Other causes of hyperandrogenismwere excluded. Imaging PUS with the trans-abdominal transducer was attempted in only one patient Acuson © scanner, using 3.5–7.5 MHz transducer; PMRI was performed in all patients with phased array coil of 1.5 T Siemens MRI scanner, with T1 and T2-weighted axial and coronal images. PCOS was defined according to the Rotterdam PCOS consensus Workshop. Results Eight girls (mean age 14,6 ± 1.47 years) are reported, one was overweight (BMI Z-score > 1 SDS), seven others were obese (BMI Z-score > 2 SDS). Mean age at menarchewas 11.58 ± 1.11 years, except for one who had not yet entered menarche. All had menstrual irregularities, acanthosis nigricans, acne, hirsutism, and biochemical characteristics of PCOS (high plasma androgens, insulin resistance, glucose/insulin ratio PUS was not contributive to the diagnosis of PCOS, whereas PMRI showed typical aspect (well delineated peripheral ovarian cysts), with increased ovarian volume and stroma. Conclusion Although PUS remains the gold standard for the diagnosis of PCOS in most cases, its limitations in overweight and obese girls are real and must be considered. If utilization of endovaginal transducer not being feasible in young virginal girls, PMRI could be a useful alternative, allowing greater delineation of structural components of the ovary and better appreciation of both its volume and structural alterations.