Abstract. The present study aimed to explore the application of 640-slice dynamic volume computed tomography (DVCT) to excretory cystography and urethrography. A total of 70 healthy subjects were included in the study. Excretory cystography and urethrography using 640-slice DVCT was conducted to continuously record the motions of the bladder and the proximal female and male urethra. The patients' voiding process was divided into early, early to middle, middle, middle to late, and late voiding phases. The subjects were analyzed using DVCT and conventional CT. The cross-sectional areas of various sections of the male and female urethra were evaluated, and the average urine flow rate was calculated. The 640-slice DVCT technique was used to dynamically observe the urine flow rate and changes in bladder volume at all voiding phases. The urine volume detected by 640-slice DVCT exhibited no significant difference compared with the actual volume, and no significant difference compared with that determined using conventional CT. Furthermore, no significant difference in the volume of the bladder at each phase of the voiding process was detected between 640-slice DVCT and conventional CT. The results indicate that 640-slice DVCT can accurately evaluate the status of the male posterior urethra and female urethra. In conclusion, 640-slice DVCT is able to multi-dimensionally and dynamically present changes in bladder volume and urine flow rate, and could obtain similar results to conventional CT in detecting urine volume, as well as the status of the male posterior urethra and female urethra.

No abstract

Background It is a challenging problem to differentiate obstructive hydronephrosis from noninvasive evaluation of renal pelvis and ureteral motility in patients. The purpose of this study was to explore the value of 640-slice dynamic volume CT (DVCT) in the quantitative measurement of upper urinary tract (UUT) pump function after acute unilateral lower ureteral obstruction in pigs. Methods In this study, a perfusion pig model was constructed by constant pressure perfusion testing of the renal pelvis and left nephrostomy. The perfusion and pressure measuring devices were connected to create a state of no obstruction and acute obstruction of the lower part of the left ureter. After successful modelling, continuous dynamic volume scanning of the bilateral renal excretion phase was performed with 640-slice DVCT, and pump functions of the renal pelvis and part of the upper ureter were calculated and analysed. No obstruction or acute obstruction of the lower part of the left ureter was observed. Pump functions of the renal pelvis and part of the upper ureter were determined. Results The results showed that after LUUT fistulostomy, the time difference between the average UUT volume and positive volume value increased gradually, and the calculated flow velocity decreased, which was significantly different from that of the RUUT. The volume difference of the LUUT increased significantly in mild obstruction. In the bilateral control, the volume change rate of the LUUT increased with mild obstruction and decreased with severe obstruction, and there was a significant difference between the left and right sides. Conclusion The continuous dynamic volume scan and measurement of 640-slice DVCT can obtain five pump function datasets of UUT in pigs with acute lower ureteral obstruction.

To explore the correlation between high-resolution computed tomography (HRCT) phenotype and pulmonary function in patients with chronic obstructive pulmonary disease (COPD). Methods: Fifty-six patients with COPD were retrospectively evaluated using pulmonary function tests (PFTs) and HRCT, and phenotypic pulmonary function parameters were analyzed. Results: Thirty-one patients were classified as having imaging phenotype A, 11 were phenotype E, and 14 were phenotype M. The total lung capacity (TLC)% of phenotype E was significantly higher than that of phenotypes A and M. The residual volume (RV) to TLC ratio (RV/TLC) in phenotype A was significantly lower than that in phenotypes E and M. The forced expiratory volume in one second percentage (FEV1%) and FEV1/forced vital capacity (FVC) of phenotype A was significantly higher than that of phenotypes E and M. Conclusion: FEV1/FVC and FEV1% were higher and RV/TLC was lower, indicating less severe emphysema, in patients with phenotype A compared with patients with phenotypes E and M. TLC% of patients with phenotype E was significantly higher than that of patients with phenotypes A and M. The degree of airflow limitation was most severe in patients with phenotype M.

Background: It is a challenging problem to differentiate obstructive hydronephrosis from non-invasive evaluation of renal pelvis and ureteral motility in patients. The purpose of this study was to explore the value of 640-slice dynamic volume CT (DVCT) in quantitative measurement of upper urinary tract (UUT) pump function after acute unilateral lower ureteral obstruction in pigs. Methods: In this study, perfusion pig model was made by constant pressure perfusion test of renal pelvis and left nephrostomy. The perfusion and pressure measuring devices were connected to create the state of no obstruction, acute obstruction of the lower part of the left ureter. After successful modeling, continuous dynamic volume scanning of bilateral renal excretion phase was performed with 640-slice DVCT, and pump functions of the renal pelvis and part of the upper ureter were calculated and analyzed. No obstruction, acute obstruction of the lower part of the left ureter. Pump functions of the renal pelvis and part of the upper ureter. Results: Results showed after LUUT fistulostomy, the time difference between the average UUTs volume and positive volume value increased gradually, and the calculated flow velocity decreased, which was significantly different from that of the RUUT. The volume difference of the LUUT increased significantly in mild obstruction. In the bilateral control, the volume change rate of the LUUT increased in mild obstruction and decreased in severe obstruction, and there was significant difference between the left and the right side. Conclusion: The continuous dynamic volume scan and measurement of 640-slice DVCT can obtain five pump function data of UUT in pigs with acute lower ureteral obstruction.