SAN DIEGO — Almost half of endometrial polyps seen on sonohysterography were missed on transvaginal ultrasound, results from a large single-center study showed.
The factors associated with lack of detection on ultrasound included smaller polyp size, multiplicity, submucosal fibroids, location of polyps, and blood flow to the polyps, Dr. Alex Hartman said at the meeting.
Between January and May of 2009, Dr. Hartman and his associates performed a blinded retrospective case study of 800 consecutive patients (mean age, 48 years) diagnosed with endometrial polyps on sonohysterography who also had preliminary transvaginal ultrasound within 48 hours of the sonohysterography.
The researchers assessed multiple factors, including patient age, size of the polyp, number of polyps, submucosal fibroids, intramural fibroids, adenomyosis, location of the polyp, blood flow, abnormal bleeding, endometrial thickness, polycystic ovaries, and fertility status. Pearson's chi-square tests and t-tests were used to compare the two samples.
Dr. Hartman, medical director of True North Imaging in Thornhill, Ont., went on to report that 433 patients (54%) with polyps diagnosed on ultrasound had their polyps seen on transvaginal ultrasound. The factors significantly associated with detection of a polyp on preliminary transvaginal ultrasound included larger polyp size (in general, the larger, the more likely seen); the presence of multiple polyps; the absence of submucosal fibroids; fundal location of the polyp; and the presence of blood flow to the polyp.
“Over the years, we found that polyps that were located in the fundus were much easier to see,” Dr. Hartman commented. “The ones that were confined to the lower uterine segment and midbody were much harder to detect.”
He also noted that 39 of the 800 patients (5%) also had submucosal fibroids. “Interestingly, only one-third of the polyps in these patients were diagnosed in the preliminary ultrasound study,” Dr. Hartman said. “So the presence of submucosal fibroids made it very difficult to see polyps on regular ultrasound.”
A large polyp is shown on sonohysterography. The blue and red represent blood flow.
Source Courtesy Dr. Alex Hartman