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Updated: Sep 12, 2026

Measurement of the Hepatic Venous Pressure Gradient and Transjugular Liver Biopsy
Published on: June 18, 2020
Abstract:
Model experiments were conducted to simulate the conditions of injection rate and pressure during retrograde pyelography. Pressures at the upper and lower end of a Ch. 5 and Ch 6. ureteral catheter were determined with 30% and 45% sodium meglumine diatrizoate and water and with different needles allowing leakage of the injected medium from a reservoir at the upper end of the catheter. It is concluded that the pressure at the upper end of the catheter may be kept within physiologic range if (1) the contrast medium is injected slowly, (2) the contrast medium leaks back around the ureteral catheter into the bladder and (3) a contrast medium with a low viscosity is used. It is advisable to use a Ch. 5 ureteral catheter instead of a Ch. 6 for retrograde pyelography.
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