Ultrasound versus Magnetic Resonance Imaging for Uterine Fibroid Mapping Before Robotic-Assisted Laparoscopic...

To (1) characterize the prevalence of ultrasound (US) and magnetic resonance imaging (MRI) in advance of robotic assisted-laparoscopic myomectomy, (2) investigate the association between pre-operative imaging (US versus MRI) and intraoperative estimates of fibroid size, number, and number multiplied by size (metric estimating fibroid burden) and (3) correlate pre-operative and intraoperative measurement agreement with clinical outcomes.

A retrospective chart review was conducted for patients who underwent laparoscopic robotic-assisted myomectomy for symptomatic uterine fibroids at a single institution, by a single surgeon, from 2013-2023.

Large southeastern urban academic hospital PATIENTS: 164 patients (Mean age=37.4 ± 4.9, 85.4% non-Hispanic African American) INTERVENTION: ultrasound or magnetic resonance imaging in advance of laparoscopic robotic-assisted myomectomy MEASUREMENTS: Individual fibroid type, size, and number were defined according to radiographic and operative reports. Intraoperative and postoperative outcomes were abstracted. Difference was assessed between pre-operative imaging and operative estimates of fibroid number, size, and burden of all fibroids in the cohort; results were stratified by anatomical type of fibroid.

Combined US/MRI (n=67, 40.9%) and MRI-only (n=69, 42.1%) were utilized for pre-operative fibroid mapping by imaging most frequently. MRI tended to underestimate, and US tended to overestimate the number of submucosal fibroids relative to operative findings (US: M=-0.1, SD=0.5; MRI: M=0.9, SD=1.3; p=0.014). Additionally, MRI underestimated, and US overestimated the size (in cm) of subserosal fibroids relative to operative findings (US: M=-1.4, SD=3.0; MRI: M=0.4, SD=3.0; p=0.008). Of the post-operative complications evaluated, only cell salvage had a statistically significant difference; a greater discrepancy between MRI and operative estimates of subserosal fibroid size was associated with greater volume of perioperative cell salvage (low: M=103.1, SD=169.2; high: M=187.5, SD=224.2; p=0.046).

Among patients undergoing laparoscopic-assisted robotic myomectomy, this pilot study observed that MRI tended to underestimate and US tended to overestimate the number of submucosal and size of subserosal fibroids relative to intraoperative estimates.