A Research On Influencing Factors Of Contrast Agent Intravasation In Hysterosalpingo-Contrast Sonography And The Related Clinical Application Based On Physical Model

Objectives To analyze the risk factors of the operators and patients on contrast agent intravasation during hysterosalpingo-contrast sonography,and explore safer and more controllable operational processes.Methods We analyzed the influencing factors of the patients who had undergone HyCoSy and constructed a physical model to analyze fluid dynamics.Then the related clinical application and in vitro experiments were conducted to validate some of the inferences of the physics model and its implications for the operators.Results Intravasation during HyCoSy had a significant impact on the image quality,especially 3D/4D image quality.Secondary infertility,the history of intrauterine surgery,endometrial thickness <6.5mm,and tubal obstruction were all risk factors of the occurrence of intravasation.In the clinical application,the intravasation rates of the two groups with different cross-sectional areas of the syringe outflow tract were 26.4% and 17.1%,P<0.05,which was mainly shown that the intravasation rate of group B with smaller cross-sectional area of the outflow tract of the syringe was lower when both fallopian tubes were unobstructed.In the in vitro bolus injection test,6 subjects used three connection methods with different outflow tract cross-sectional areas to inject contrast agents,and observed that the smaller the outflow tract cross-sectional area,the longer the average bolus injection time.And groups with syringe needles(B and C)demonstrated better performance in the difficulty of syringe connection and the score of disconnection at the connection point than group with no syringe needle(A),whose bolus injection speed could be improved.The control score of group C with the smallest syringe needle was lower than that of groups A and B,P<0.001.Conclusions The factors of both the operators and the patients could lead to intravasation in HyCoSy,and the influence of different operators on the reverse flow rate cannot be ignored.The assistants should inject the contrast agent at a slow and constant rate.To use needle as a flow restrictor and passive control of the flow rate of the contrast bolus was a simple and easy way to improve the procedure.PartⅠ A Research on Influence of Contrast Agent Intravasation on Image Quality and the Influencing Factors of Contrast Agent Intravasation in Hysterosalpingo-Contrast SonographyObjectives To analyze the influence of contrast agent intravasation on image quality and the influencing factors of contrast agent intravasation during hysterosalpingo-contrast sonography.Methods We analyzed the medical records and examination results of 299 patients undergone HyCoSy examination,and explored the influencing factors of contrast agent intravasation.Results When contrast agent intravasation occurred,the proportion of Alevel images in the 3D/4D group(12.8%)and the proportion of A-level images in the 2D group(45.7%)were significantly reduced compared with those without intravasation,P<0.001.Secondary infertility,history of intrauterine surgery,endometrial thickness <6.5mm,and tubal obstruction were all risk factors of the occurrence of intravasation.Conclusions Intravasation during HyCoSy had a significant impact on the image quality,especially 3D/4D image quality.Secondary infertility,the history of intrauterine surgery,thin endometrial thickness,poor tubal patency and other factors might lead to the occurrence of intravasation.Sonographers and gynecologists should be familiar with the influencing factors of intravasation,and choose the appropriate timing of HyCoSy to reduce the occurrence of intravasation and other complications after thoroughly explanation and communication with patients.Part Ⅱ A Research on the Operator’s Influencing Factors of Contrast Agent Intravasation in Hysterosalpingo-Contrast Sonography Base on a Physical ModelObjective To analyze the risk factors of the operators on contrast agent intravasation during hysterosalpingo-contrast sonography.Methods We constructed a physical model to analyze fluid dynamics,and the examination results of 399 HyCoSy patients were collected to verify s the inferences of operator-related influencing factors.Results The intravasation rates of the two groups with different crosssectional areas of the syringe outflow tract were 26.4% and 17.1%,P<0.05,which was mainly shown that the intravasation rate of group B with smaller crosssectional area of the outflow tract of the syringe was lower when both fallopian tubes were unobstructed.Conclusions The influence of different operators on the contrast agent intravasation rate of HyCoSy cannot be ignored.The assistants of HyCoSy examination should inject the contrast agent slowly and steady,control the flow into the uterine cavity per unit time,slow down the rising speed of intrauterine pressure,and avoid the accumulation of contrast agent in the uterine cavity,so as to reduce the intravasation caused by operator factors.Part Ⅲ In Vitro Validation Study of Research of HysterosalpingoContrast Sonography Based on Physical ModelObjective To analyze the impact of different connection methods on the operator during hysterosalpingo-contrast sonography.Methods Six subjects were applied three different ways to connect the syringe to the uterine catheter,and compared the average duration of their bolus injection of the same 20-m L contrast medium and the scores from both operators and subjects on the three connection methods.Results Six subjects used three connection methods with different outflow tract cross-sectional areas to inject contrast agents,and observed that the smaller the outflow tract cross-sectional area,the longer the average bolus injection time.And groups with syringe needles(B and C)demonstrated better performance in the difficulty of syringe connection and the score of disconnection at the connection point than group with no syringe needle(A),whose bolus injection speed could be improved.The control score of group C with the smallest syringe needle was lower than that of groups A and B,P<0.001.Conclusions After the syringe was covered with the needle,it could be better connected with the uterine catheter,and it was not easy to slip off.The use of a small needle could make it easier for novices to control the injection speed and maintain the same amount of contrast agent for a longer operation time,which was a simple and easy ways to improve the procedure.