Objective:To compare the effect of F7.5 ureteroscope and other types of ureteroscope (F8.5, F9.0, F9.2, F9.6) in the control of intrapelvic pressure during operation.Methods:F7.5 super thin flexible ureteroscope and other 4 kinds of disposable flexible ureteroscopes (F8.5, F9.0, F9.2, F9.6) were combined with 3 kinds of ureteral guidance sheaths to form 15 endoscope-sheath combinations. The real outer diameter of each flexible ureteroscope was measured and the effective ratio of endoscope-sheath diameter was calculated. The real outer diameter of each soft mirror was measured and the effective sheath ratio was calculated. The irrigation during lithotripsy was simulated in a 3D printed kidney model, the irrigation pressure of 50-500 cmH 2O was set, and the stable intrapelvic pressure and flow rate were measured. The line chart was drawn and the relationship between intrapelvic pressure and irrigation pressure was analyzed by linear regression. The intrapelvic pressure between different endoscope-sheath combinations and different endoscope groups were compared respectively. Results:The ratio of endoscope-sheath diameter for all combinations ranges from 0.62 to 0.92, with 0.75, 0.68 and 0.62 for the F7.5 flexible ureteroscopes and F10/12, F11/13 and F12/14 sheath combinations respectively. Intrapelvic pressure and flow rate showed an approximately linear relationship with irrigation pressure in all groups. The F7.5 flexible scope with the F10/12, F11/13 and F12/14 sheaths all provided intrapelvic pressures below 40 cmH 2O. The F12/14 sheath-F7.5 scope combination produced the lowest intrapelvic pressure of 1.47 cmH 2O at 50 cmH 2O irrigation pressure and the highest flow rate of 74.24 ml/min at 500 cmH 2O irrigation pressure. When combined with the F10/12 sheath, only the F7.5 flexible scope was able to maintain a safe intrapelvic pressure of only 25.90 cmH 2O throughout. Analysis of the variability of intrapelvic pressure using the combination of instruments as the grouping variable suggested a significant overall difference( P<0.05). Analysis of the variability between groups using the different flexible scope as the grouping variable showed that the F7.5 scope group had significantly lower intrapelvic pressure compared to the other four groups( P<0.05). Conclusions:The F7.5 super thin flexible scope has the best intrapelvic pressure control of the five flexible scopes due to the significantly reduced ratio of endoscope-sheath diameter for the instrument combination and the ability to fit a thinner guide sheath while maintaining safe pelvic pressure.

Objective:To investigate the feasibility and safety of ultrasound-guided percutaneous submandibular region puncture and drainage(PSPD) for treating parapharyngeal space abscess (PPSA).Methods:The clinical data of 26 patients with PPSA receiving PSPD from January 2015 to December 2019 in the Third Central Hospital of Tianjin were retrospectively analyzed.Results:All 26 patients successfully underwent puncture and catheterization with a primary success rate of 100%. After catherization, pain relieved within 12-24 hours, body temperature returned to normal within 24-48 hours, white blood cell(WBC) and C-reactive protein(CRP) returned to normal within 48-96 hours. The catheterization duration ranged from 5 to 14 days and the average time was 7 days. There were statistically significant differences in the body temperature, maximum abscess diameter, WBC and CRP between pre-operation and 7 days after operation(all P<0.001). None of the 26 patients experienced any serious complications such as major vessels, nerve or glands injury. Bacterial cultures were positive in 18 patients and the most common bacteria was hemolytic streptococcus. Conclusions:PSPD is an effective, safe and minimally invasive method for the treatment of PPSA as an alternative to operative incision and drainage.

Hepatocellular carcinoma (HCC) is a malignant tumor with high incidence in China and the whole world, and early diagnosis and treatment are the key to improving the prognosis of patients. To facilitate the communication and cooperation between doctors of different centers and specialties, American College of Radiology issued the first edition of contrast-enhanced ultrasound (CEUS) Liver Imaging Reporting and Data System (LI-RADS) in 2016 to standardize the technical terms, techniques, interpretation, reporting, and data collection for liver imaging and perform HCC risk stratification for different focal liver lesions. This article reviews the development and clinical application of CEUS LI-RADS and believes that the application of CEUS LI-RADS has a great potential value in the clinical management of focal liver lesions in the population at a high risk of HCC, and the applicable population and indications for CEUS LI-RADS will continue to expand in the near future, so as to provide better service to clinical practice.