Accuracy of Hystro-Salpingo-Foam-Sonography (HYFOSY) as Tubal Patency Test in Comparison to Laparoscopy in Infertile Patients

Tubal patency testing is an essential part of female subfertility evaluation . Tubal abnormalities are seen in 30-40% of female subfertility patients . Laparoscopy with chromopertubation is considered to be the gold standard diagnostic procedure . Laparoscopy is an invasive test, with a risk of intra-abdominal bleeding, visceral damage, and risks related to general anaesthesia. Traditionally, Hysterosalpingography(HSG) is a less invasive less expensive first-step alternative, which has been used for decades with disadvantages such as radiation exposure, discomfort, or even abdominal pain. Hysterosalpingo-Contrast Sonography (HyCoSy) was introduced as an alternative using either contrast media or saline. The accuracy of HyCoSy is comparable to that of HSG and LSC being reference standards for tubal patency testing.However, hyperechogenic contrast media such as Echovist\_ (Schering AG, Berlin) and SonoVue\_ (Bracco, Milan)are either no longer available or not licensed for tubal patency testing. Hysterosalpingo-Foam Sonography (HyFoSy) was developed as an alternative for contrast HyCoSy and was introduced in 2010 as a first-line office tubal patency test.Foam is used in the HyFoSy technique to visualize the fallopian tubes and is created by rigorously mixing 5mlExEm\_-gel (containing hydroxyethyl cellulose and glycerol,IQMedical Ventures BV, Rotterdam, TheNetherlands) with 5ml purified ExEm\_-water. The ExEm\_-foam is sufficiently fluid to pass the fallopian tubes and in the mean time sufficiently stable to show echogenicity for at least five minutes, which is an advantage over saline. In a review on safety aspects and side effects of ExEm-gel it was considered to be appropriate and safe for tubal patency testing. In 2017, HyLiFoSy combined with power Doppler (PD)(HyLiFoSy-PD) technique was described as a possibly less painful and easier to detect on ultrasound alternativeto HyFoSy and HyCoSy, which can be used whenever the contrast media used with both are eithe