Application Of CT Perfusion And Correlation Between CT Perfusion Parameters And Microvessel Densities In Renal Cell Carcinomas

Objective1. Acquisition of all CT perfusion imaging parameters of normal renal cortex and medulla, including blood flow (BF), blood volume (BV), mean transit time (MTT) and capillary permeability surface area product (PS). Further acquisition include getting the preliminary range of values of all CT perfusion imaging parameters regarding normal kidney;Testing whether significant differences exist in CT perfusion imaging corresponding parameters, between renal cortex and medulla;Testing whether significant discrepancies exist in CT perfusion imaging corresponding parameters of renal cortex, between the left side and right, similarly, discrepancies within renal medulla.2. Testing whether significant discrepancies exist in CT perfusion imaging corresponding parameters, between renal cell carcinomas (RCCs) and normal renal cortex, between RCCs and normal renal medulla.3. Testing whether significant discrepancies exist in unit renal blood flow of CT perfusion imaging between normal kidney and contra-lateral healthy kidney in RCC patients. Furthermore, to analyze the relationship between renal blood flow of CT perfusion imaging and effect renal plasm flow (ERPF) of radio-nuclide labeled micro-spheres about contra-lateral healthy kidney in RCC patients.4. To analyze the relationship between the CT perfusion parameters andMicrovessel Densities (MVD) in RCCs. Materials and Methods1. CT perfusion was performed on 26 healthy individuals with multi-slice spiral CT(MSCT). All data were sent to Advanced Workstation 4.2 and perfusion parameters (including BF, BV, MTT, and PS)of the normal kidney were obtained with GE Perfusion III software;To test for the significance discrepancies in perfusion parameters between normal renal cortex and medulla, by group /-test for independent samples;To test for the significance of difference in renal cortex perfusion parameters between the left side and right renal as well as renal medulla by paired /-test for dependent samples.2. CT perfusion was performed by MSCT in 35 patients with RCCs which were confirmed by consequently operation and histopathology. For each tumor, the maximum slice were selected as the target slice. All data were sent to Advanced Workstation 4.2 and perfusion parameters (including BF, BV, MTT, and PS) of RCCs were obtained with GE Perfusion III software. To test for the significance discrepancies in perfusion parameters between RCCs and normal renal cortex with group t-test for independent samples, the same as between RCCs and normal renal medulla.3. All data of 24 patients of RCCs, were sent to Advanced Workstation 4.2. The target slice of contra-lateral healthy kidney was chosen nearest to the renal hilum among the 4 slices, and the region of interest (ROI) includes all renal parenchyma of the chosen slice except for renal sinus. The BF of contra-lateral healthy kidney was obtained with GE Perfusion III software as the unit renal blood flow;the unit renal blood flow of 18 normal individuals (total 36 kidneys) were obtained by means of the same method;To test for the significance discrepancies in unit renal blood flow between contra-lateral healthy kidney of RCCs and normal kidney with group /-test for independent samples.CT perfusion of raw data from 13 patients of RCCs contained within above 24 were sent to Advanced Workstation 4.2 and BF parameters of their renal parenchyma (choosing the layer nearest to the renal hilum) were obtained with Perfusion III software;To get the effective renal plasma flow (ERPF) by using radio-nuclide labeled microspheres;The correlation of unit renal blood flow regarding CT perfusion and ERPF of radio-nuclide labeled microspheres were analysed.4. CT perfusion were performed in 30 patients of RCCs by MSCT. All the data were sent to Advanced Workstation 4.2 and perfusion parameters (including of BF, BV, MTT, and PS)of tumorous solid components were obtained with Perfusion III software;MVD was examined immunohistochemically using SP techniques. The correlation of the perfusion parameters and MVD was studied respectively.Results1. Besides MTT (P=0.344>0.05), the same perfusion parameter of the ipsilateral renal cortex and medulla all have significant differences (PO.01). Renal cortex is above medulla;the same perfusion parameter of renal cortex between the left side and right has no significant difference (P>0.05), similarly for renal cortex between the left side and right.2. The same perfusion parameter between renal cortex and solid components of RCCs, have significant differences (PO.01). BF value, BV value and PS value of renal cortex is above RCCs, but MTT value is opposite. The perfusion parameters, BF value, BV value and MTT value, between renal medulla and solid components of RCCs, have significant difference (PO.01) too, but PS value has no significant difference.3. The CT perfusion imaging average unit renal blood flow of 24 contra-lateral healthy kidney of RCCs is SO^SOiee^Sml-min^-lOOg^.The average unit renal blood flow of 18 normal individuals (36 kidneys) is 343.51±91.63ml-min'1-100g"1. Both unit renal blood flow of 24 contra-lateral healthy kidney with RCCs and 18normal individuals has no significant difference;The renal blood flow of CT perfusion imaging has positive correlation to corresponding ERPF of radio-nuclide labeled microspheres about contra-lateral healthy kidney of 13 cases of RCCs (r=0.577, PO.05).4. Mean value of MVD was 47.67±30.92 (strip) in 30 patients. Mean value of BF, BV> MTTandPS were 301.74±250.41ml-min"1-100g'1, 18.17± 11.54ml-100g"1, 6.62±4.91s, and 21.59±12.75ml-min"1-100g'1, respectively. There was positive correlation between BF value> BV value and MVD, corresponding (tbv^OJSS and rev=0.632, PO.Ol). MTT value of CT perfusion imaging has negative correlation to MVD of tumors(r=-0.487, PO.01).Conclusion1. CT perfusion imaging can get many perfusion parameters of renal cortex and medulla, quantitative analysis of the change of renal haemodynamics. Perfusion parameters between normal renal cortex and medulla are different. Among them, besides MTT, BF value, BV value and PS value has significant differences. By Affirming that all CT perfusion parameters of normal kidney provide a new means of functional radiological examination in order to research how haemodynamics affect change in renal disease.2. Perfusion parameters between RCCs and normal renal cortex are different, similarly, between RCCs and medulla, except PS. Among them, BF value, BV value and PS value have significant differences. Affirming perfusion representation of RCC avails for diagnosis s differential diagnosis and evaluating effect after interventional therapy.3. Both contra-lateral healthy kidney in patients with RCCs and normal kidney has no significant difference regarding unit renal blood flow. Furthermore, the unit renal blood flow of CT perfusion imaging has positive correlation with corresponding ERPF of radio-nuclide labeled microspheres. According to the aboveresult, CT perfusion imaging can provide a new technique for measuring contra-laterally healthy renal function in RCC patients.4. CT perfusion parameters(I^ BV> MTT) of RCCs was approved to correlate with MVD significantly. CT perfusion may provide a new method to study the angiogenesis of RCCs in vivo, which will be helpful in optimization of a reasonable treatment protocol.