NEW YORK (Reuters Health) – Sonography performed to investigate endometrial pathology in women with abnormal bleeding is easier to perform with gel instillation to distend the uterine cavity rather than saline instillation, a Belgian group report. Furthermore, results are just as accurate.

Dr. Thierry Van den Bosch, of University Hospitals Leuven, and colleagues explain in an online publication from Fertility and Sterility that adequate distension can be difficult to maintain with saline instillation, and it’s possible that transtubal flow might lead to seeding of malignant cells in the abdominal cavity. Gel instillation could overcome these problems.

To look into this, the team fist evaluated 402 women with abnormal bleeding using saline instillation sonography, and then the next 402 women using gel instillation sonography.

Technically, the gel procedure was more successful. The procedural failure rate was 5.0% for saline instillation versus 1.8% for gel instillation, and corresponding failure rates due to inadequate distension were 1.5% versus 0.3%.

Pathology, defined as endometrial hyperplasia, polyp, cancer, or intracavitary myomas, was diagnosed in 49% of the saline instillation group versus 40.2% of patients in the gel instillation group; the difference was not statistically significant. “The sensitivity was 77.8% and 85.0%, respectively (NS). The negative predictive value was 79.1% for saline instillation sonography and 88.6% for gel instillation sonography,” the investigators report.

Dr. Van den Bosch and his associates note that a drawback of using gel is the potential to misdiagnose blood clots as polyps, because saline can be used to flush away clots.

Overall, they conclude, both techniques are feasible and accurate. However, “Gel has some advantages over saline: stable filling of the uterine cavity, no need for balloon catheters, improved patient comfort, and, theoretically, a lower risk for intraperitoneal dissemination of malignant cells. Therefore, we recommend the use (of) gel instillation sonography instead of saline instillation sonography.”

Reference:

Detection of endometrial pathology using saline infusion sonography versus gel instillation sonography: a prospective cohort study

Fertil Steril 2010.