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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.
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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.
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Objective To evaluate the clinical value of CT urography (CTU) in quantitative analysis of single?kidney renal glomerular filtration rate (GFR) in patients with renal tumor and hydronephrosis.Methods A total of 49 patients with renal tumor or hydronephrosis from January 2018 to September 2018 in the Second Hospital of Tianjin Medical University were prospectively collected. In all cases, the CT urography and 99mTc?DTPA renal dynamic imaging data and related clinical data were collected. All patients were divided into two groups: the experimental group (39 patients with a total of 78 kidneys) and the validation group (10 patients with a total of 20 kidneys). According to the presence or absence of renal diseases, the kidneys of the experimental group and the validation group were further divided into four groups, namely, the single kidney group, the tumor group, the stagnant water group and the healthy group. The CT urography protocol consisted of noncontrast, arterial phase, nephrographic, and excretory phase imaging. The total renal GFR was determined by CT measurement of renal clearance of contrast media (CM), and the total CT?GFR was then split into single?kidney CT?GFR by a left and right kidney proportionality factor. Differences between CT?GFR and SPECT?GFR measurements in each group of the experimental group was compared by paired?sample t test. Correlations between CT?GFR and SPECT?GFR in the experimental group and their correlations with RPV was analyzed by Pearson method. The Bland?Altman mapping method was used to evaluate the consistency between CT?GFR and SPECT?GFR in the experimental group. Results Paired difference between single?kidney CT?GFR (48.76 ± 18.50) ml·min-1·1.73 m-2 and single?kidney SPECT?GFR (45.68±17.95) ml·min-1·1.73 m-2 in the experimental group, P<0.05, demonstrating 6.8% systemic overestimation. A good correlation(r=0.80, P<0.01) and consistency (± 22.50 ml·min-1·1.73 m-2, ± 49.2% measurement deviations) was revealed between both measurements. There were positive correlations between CT?GFR and SPECT?GFR in the renal tumor group, hydronephrosis group, and healthy kidney group (r=0.67, 0.92, 0.80; P<0.01) respectively, and with good agreement (95% CI measurement deviation<30 ml·min-1·1.73 m-2). In all validation groups, there was no statistical difference between the estimated and true values of the Gates?GFR (all P>0.05). Pearson Correlation analysis showed that the correlations between CT?GFR and RPV in all experimental groups were better than the correlation between Gates?GFR and RPV (P<0.05). Conclusions This study demonstrated the feasibility of using CT urography to measure single?kidney GFR, verifying its application value in diseases such as kidney tumors and obstructive hydronephrosis, and proved that the proposed single?kidney CT?GFR correlates better than the SPECT?GFR with RPV.
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Background: CT has evolved from single–detector row scanners into multi–detector row helical volumetric acquisition techniques, and these advances have had a significant impact on imaging of the urinary tract. Aim and objectives: To evaluate the CTU compare to other imaging modalities for urinary tract abnormalities in light of present knowledge, To study the role of CTU in evaluation of various abnormalities those are not detected by conventional IVP, Benefits of CTU over IVP, To provide information about the extent of the lesions involving kidneys and its relation to surrounding structure and Characterizing the lesions whether they are benign or malignant and helping the surgeons for the further management, Grading the renal injuries. Materials and methods: Data was collected from patients who attended the surgical O.P.D. or emergency of S.S.G.H., Baroda with clinically suspected renal abnormalities. A study was conducted over a period of two years on 50 patients with clinically suspected renal abnormalities. Informed consent was taken from every patient. Patients were evaluated with Multidetector Computed Tomography (G.E. Bright Speed). Results: Our Study included 10 patients of renal stones, 8 patients of renal masses, 3 patients of pyelonephritis, 7 patients of renal injury, 5 patients of PUJ obstruction, 7 patients of ureteric stricture, 5 patients of anomalies, and 5 patients of bladder mass. Among all pathology CT urography is more helpful and gives better imaging findings as compare to conventional urography that helps in better management of patients. Conclusion: CTU gives reliable information not about the extent of lesion but also the characteristics of lesions which makes surgeons to take proper decision aboutthe further management of patients, it also avoids unnecessary laparotomy surgery in case of blunt abdominal trauma patients by giving the precious extent of renal injuries. For all these gold standard benefits of MDCTU over conventiona Rathva AM, Singla H. MDCT urography as a one stop shop for urinary tract abnormalities at present era. IAIM, 2016; 3(3): 52-64. Page 53 IVP makes MDCTU as “one stop shop” for urinary tract abnormalities and nearly completely replacing the IVP in recent era.
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Objective To establish a dual contrast-enhanced ultrasonography (DCEUS) method for diagnosing the upper urinary tract obstructive diseases, and to discuss the diagnosis criterion and value. Methods A total of 147 patients with upper urinary tract obstructive diseases underwent dual contrast-enhanced ultrasound examination. A dose of SonoVue solution was directly injected into the renal pelvis via the puncture tube, and the antegrade contrast agent movement within the upper urinary tract was continuously monitored under CPS mode. Meanwhile, intravenous contrast-enhanced ultrasound was performed to observe the capillary filling of the urinary tract and surrounding structures, that is what we called DCEUS. And all the patient received magnetic resonance urography (MRU) and urinary contrast-enhanced CT within one week. With the operative findings and/or postoperative pathology taken as the golden standard, the accuracies of DCEUS and MRU in diagnosing the obstructive levels and severity of upper urinary tract obstruction were compared, and the accuracies of DCEUS and contrast-enhanced CT in diagnosing causes of the obstruction were compared. Results (1)The accuracy of DCEUS in revealing the obstructive levels were 100%, showing no significant difference with MRU(98. 6%)(P>0. 05). (2)The accuracy of DCEUS in evaluating the severity of upper urinary tract obstruction was 98. 6%, which was significantly better than that of MRU(89. 8%, P0. 05). (4) No complications were found during renal pelvis puncture or administration of SonoVue in the 147 patients,and no late complications were noticed during 1-6 months ultrasound follow-up in the 143 patients whowere followed up. Conclusion DCEUS is a safe, effective method; it can accurately locate the upper urinary tract obstruction and help to make qualitative diagnosis, and combination with percutaneous nephrostomy can yield even better clinical values.
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Objective To discuss the application value of multislice CT (MSCT) in diagnosis of ureteral biology variation and diseases.Methods The MSCT data of 51 patients with suspected ureteral biology variation and diseases were retrospectively analyzed.The data of MSCT images included plain scan,renal cortical phase,renal parenchyma phase and excretion phase.The MSCT images of renal cortical phase,renal parenchyma phase and excretion phase were reconstructed respectively to gain the 3D images of renal arteries,veins and urinary passage.Results Among the 51 patients,1 patient with traumatic ureteral rupture,10 patients with ureteral biology variation diseases,14 patients with stone of ureter,2 patients with polyp of ureter,3 patients with non-specificity ureteritis,3 patients with tuberculosis of ureter,1 patient with endometriosis,17 patients with carcinoma of ureter.Satisfied 3D images of renal arteries,veins and urinary passage could be reconstructed.And the imaging diagnosis of 51 patients were all in accord with their clinical diagnosis or pathologic diagnosis.Conclusion MSCT can obtain high qualified images,and this technique should become the preferred inspection item of ureteral biology variation and diseases.
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Objective To detail the utility of CT scan in detection of urinary stones induced by melamine tainted formula. Material and Methods A total of 1062 children fed with melamine-contaminated infant formula were screened for urinary stones in our institute from September through December 2008. Ultrasonography of the urinary tract system was performed in all these children. If the children with suspected stones or severe obstruction were presented after ultrasound examination, themulti-detector row CTurographic examination was advocated subsequently. Results Ultrasound examination in combination with multidetector row CT urography could increase the diagnostic rate from 3.4% (36/1062) by ultrasound examination alone to 4.6% (49/1062). Conclusions The specificity and sensitivity of the multidetector row CT urographic examination is higher than ultrasonography.