Hysterosalpingo‐lidocaine‐foam sonography combined with power Doppler imaging (HyLiFoSy‐PD) in tubal patency assessment: ‘flaming tube’ sign

Two- (2D) and three-dimensional (3D) ultrasound imaging is used frequently for tubal patency testing with relatively high accuracy, particularly when performed by experts and using foam as contrast medium1. However, there are still some drawbacks related to the technique that preclude its worldwide use, including the cost and availability of contrast media, the procedure-related pain and the need for appropriate training to obtain competence in the performance of tubal patency testing1. In this article, we describe a novel technique, hysterosalpingo-lidocaine-foam sonography combined with power Doppler imaging (HyLiFoSy-PD), which allows assessment of the ‘flaming tube’ sign as an indicator of tubal patency. We believe that this technique offers advantages related to cost, availability and ease of image recognition; additionally, the use of lidocaine in the contrast agent could potentially reduce the pain associated with the procedure. During offline assessment of the 3D volumes, the standard multiplanar mode, after correcting the uterine position4, provides sufficient imaging quality (Figure 1). However, the image quality can be improved by assessing only the coronal plane of the multiplanar mode and combining this view with volume contrast imaging, using the following settings: glass body, surface mode for both grayscale and power Doppler ultrasound, slice thickness of 5 mm, transparency gray = 250, threshold low gray = 50, transparency color = 100 and threshold low color = 100 (Figure 2). The ‘flaming tube’ sign can be combined with other modern ultrasound techniques5 to facilitate identification of tubal occlusion and its causes, and guide specific treatment (Figure S1). We are encouraged by the initial images and potential advantages of HyLiFoSy-PD. We believe that the ‘flaming tube’ sign has the potential to improve the diagnostic accuracy and reliability of tubal patency testing, as it can be identified easily, even by patients. Additionally, the use of lidocaine gel in the contrast medium provides images of good quality, reduces the cost of the technique and may have a benefit with respect to pain relief. However, further studies are needed to assess the quality of images obtained with this foam medium in comparison with other contrast media, as well as evaluate whether the use of lidocaine gel in the contrast medium is able to reduce pain during or, especially, after the procedure. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.