Résumé
Objective To explore the optimization of CT urography imaging parameters and the control measures of radiation dose to patients with different body mass index.Methods A total of 133 patients who were required to undergo CT urography were prospectively selected in terms of three different types of CT urography scan;firstly,conventional parameter scan (120 kV,CARE Dose4D);secondly,low kV scan (BMI ≤ 22.9 ∶ 80 kV,22.9 ＜ BMI ＜ 30 ∶ 100 kV,BMI ≥ 30 ∶ 120 kV,CARE Dose4D)and thirdly,low mAs scan (120 kV,40％ reduction in mAs on CARE Dose4D).Noise,signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of all images were measured as objective evaluation indicators of image quality.The subjective evaluation of the images was performed by two radiologists who had been working for more than five years using a double-blind method and a 5-score system evaluation.The effective dose values (CTDIvol,DLP,E) in each group were measured.Results Patients' effective dose was decreased by 77.7％ in 80 kV group and 38.3％ in 100 kV group,with a statistical difference between the two groups (Z =-3.330,-5.559,P＜0.05).There was a statistically significant difference in renal cortex noise,SNR,CNR and ureteral noise between the 80 kV scan and the routine scan (Z =-3.705-2.392,P＜0.05),but no significant difference in ureteral SNR,CNR and renal pelvis noise,SNR,CNR (P＞ 0.05).There was a statistically significant difference in renal cortex noise and SNR between the 100 kV scan group and the routine scan group (Z =-5.096,-3.566,P＜ 0.05),but no statistical difference in renal cortex CNR,renal pelvis and ureteral noise,SNR,CNR (Z =-5.086,-5.912,-2.842,P＞0.05).The effective dose from low mAs scan in the three types of patients was decreased by 38.3％,32.0％,and 34.7％,respectively,with a statistical difference between them (P ＜0.05).There was no significant difference in noise,SNR,and CNR between renal cortex,renal pelvis and ureter (P＞0.05) besides ureteral CNR in the 22.9 ＜ BMI ＜ 30 group (Z =-2.587,P＜0.05).The subjective evaluation scores of all images were greater than 3 points.Conclusions In this study,the scan method for low kV and low mAs used for patients with different body mass index can effectively reduce the radiation dose to patients and meet the requirements of clinical diagnosis.
Résumé
Objective@#To explore the optimization of CT urography imaging parameters and the control measures of radiation dose to patients with different body mass index.@*Methods@#A total of 133 patients who were required to undergo CT urography were prospectively selected in terms of three different types of CT urography scan; firstly, conventional parameter scan (120 kV, CARE Dose4D); secondly, low kV scan (BMI ≤ 22.9∶80 kV, 22.9 < BMI < 30∶100 kV, BMI ≥ 30∶120 kV, CARE Dose4D) and thirdly, low mAs scan (120 kV, 40% reduction in mAs on CARE Dose4D). Noise, signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) of all images were measured as objective evaluation indicators of image quality. The subjective evaluation of the images was performed by two radiologists who had been working for more than five years using a double-blind method and a 5-score system evaluation. The effective dose values (CTDIvol, DLP, E) in each group were measured.@*Results@#Patients′ effective dose was decreased by 77.7% in 80 kV group and 38.3% in 100 kV group, with a statistical difference between the two groups (Z=-3.330, -5.559, P<0.05). There was a statistically significant difference in renal cortex noise, SNR, CNR and ureteral noise between the 80 kV scan and the routine scan (Z=-3.705-2.392, P<0.05), but no significant difference in ureteral SNR, CNR and renal pelvis noise, SNR, CNR (P>0.05). There was a statistically significant difference in renal cortex noise and SNR between the 100 kV scan group and the routine scan group (Z=-5.096, -3.566, P<0.05), but no statistical difference in renal cortex CNR, renal pelvis and ureteral noise, SNR, CNR(Z=-5.086, -5.912, -2.842, P>0.05). The effective dose from low mAs scan in the three types of patients was decreased by 38.3%, 32.0%, and 34.7%, respectively, with a statistical difference between them (P <0.05). There was no significant difference in noise, SNR, and CNR between renal cortex, renal pelvis and ureter (P>0.05) besides ureteral CNR in the 22.9 < BMI < 30 group (Z=-2.587, P<0.05). The subjective evaluation scores of all images were greater than 3 points.@*Conclusions@#In this study, the scan method for low kV and low mAs used for patients with different body mass index can effectively reduce the radiation dose to patients and meet the requirements of clinical diagnosis.
Résumé
Along with the rapid development of interventional radiology, a simultaneous increase of the treatment was carried out for diseases of urinary system, including nephrostomy, balloon dilatation and stenting for uninary tract obstruction, calculus removing techniques, stenting for prostatic hypertrophy; TAE/TACE and ablation therapy for benign/ malignant tumors; angioplasty with balloon or stent for stenosis of renal artery or vein; embolotherapy for hemorrhagic diseases; interventional treatment for complications after renal transplatation, and so on. All the above mentioned techniques for urinary diseases have already provided with good results and futher research will bring a promising future.
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Objective To evaluate the causes,prevention and treatment ot laparoscopic comphca- tions in urologic surgery.Methods From May 2000 to May 2004,135 urologic laparoscopies were per- formed,including 17 transperitoneal laparoscopies and 118 retroperitoneal laparoscopies.Of the135 cases,26 had adrenal adenoma extirpation;31 had roof-removal and decompression of renal cyst;25 had radical ne- phrectomy;6 had pyeloplasty;2 had partial resection of renal capsula and encapsulation of the great omen- tum;2 had partial nephrectomy;4 had pelviureteral resection;13 had ligation of renal pedicle lymphatic ves- sel;2 had ureterolysis;7 had ureterolithotomy;12 had ligation of spermophlebectasis;5 had exploration,re- duction and fixation of undescended testis.The intra-and post-operative complications were retrospectively reviewed and clinically analyzed.Results Overall,14 cases(10.4%)had complications.Intraoperative complications occurred in 10 cases,including 6 cases of peritoneal injuries,which were clamped during oper- ation;4 of vascular injuries,which resulted in conversion to open surgery.Postoperative complications oc- curred in 4 cases,including 2 of subcutaneous emphysema,which was spontaneously absorbed at 5 and 7 d after operation;1 of incision seepage,which was drained for 40 d and then disappeared;and 1 of urine reten- tion,for which urethral catheterization was kept for 3 d and then the patient had voluntary voiding.No death occurred in this series.Conclusions Understanding the characteristics of laparoscopic complications in u- rologic surgery and systematic training of the surgeons can reduce the occurrence of complications.