ABSTRACT
Objective:To compare the detective effect between color Doppler twinkling artifact and B-mode ultrasonography for kidney stones in order to develop an ultrasonic model that can more easily and more accurately detect kidney stone.Methods: 9 patients with kidney stone who were confirmed by CT scan in recently were selected to accepted two methods (color Doppler twinkling artifact and B-mode ultrasonography) to detect kidney stone. The video fragments of upper pole, interpolar and lower pole were created by three radiologists and the results were diagnosed by them.Results: In dual kidneys of the nine patients, 32 stones with average size of (8.9±7.5) mm were found. The sensitivity, specificity, positive predictive value and negative predictive value of the B-mode ultrasonography were 71%, 48%, 52% and 68%, respectively, while those of color Doppler twinkling artifact were 56%, 74%, 62% and 68%, respectively.Conclusions: In the detection of kidney stones, B-mode ultrasonography is more sensitive when is used alone, but color Doppler twinkling artifact has more high specificity. The color Doppler twinkling artifact should be applied in more clinical practices, and a new commercial ultrasonography mode that used basic acoustic difference and is special for detection of kidney stone should be researched and developed so as to improve the detection of kidney stone.
ABSTRACT
Objective To quantitatively analyze the value of color Doppler twinkling artifact and CT in distinguishing urinary stone composition of uric acid from that of cystine,and to assess the ability of color Doppler twinkling artifact and CT to diagnose urinary stone composition of uric acid.Methods Artificial stones made of uric acid and cystihe were inserted in porcine kidneys respectively.Color Doppler ultrasound and CT scanning were performed in vitro and twinkling artifact videos were recorded.The CT attenuation value,the width and length of twinkling artifact (TAW,TAL) were measured.The color pixels representing twinkling artifact intensity (TAI) were calculated.The differences between artificial cystine and artificial uric acid stones in TAW,TAL,TAI and CT attenuation value were compared.The receiver operating characteristic (ROC) curve was used to assess the ability of TAW,TAL,TAI and CT attenuation value to diagnose urinary stone composition of uric acid.Results The TAW [(4.16 ± 1.54)mm vs (4.97 ± 1.93)mm],TAL[(3.75 ± 1.05)mm vs (5.12 ± 2.51)mm] and TAI [(3 005.50 ± 812.33) vs (5 433.86±2 505.81)] of artificial cystine stones were less than those of artificial uric acid stones while the CT attenuation value of artificial cystine stones [(573.75 ± 110.10)HU vs (364.09 ± 67.28)HU] were greater (P ＜0.05).The ROC curve was displayed to diagnose urinary stone composition of uric acid,and the area under curve of CT attenuation value was bigger than that of TAI (0.936 vs 0.817,Z =2.308,P =0.021).Combination of color Doppler twinkling artifact and CT value would dramatically increase the diagnostic accuracy to 98％.Conclusions Both color Doppler ultrasound and CT were reliable examinations for distinguishing urinary stone composition of cystine from that of uric acid.Combination of color Doppler ultrasound and CT would be good references to diagnose urinary stone composition of uric acid.
ABSTRACT
Objective To investigate the diagnostic value of twinkling artifact in urinary calcium stones.Methods Calcium oxalate monohydrate,hydroxyapatite and whitlockite stone phantoms were prepared and embedded in porcine kidneys for ultrasound scanning.The length and width of twinkling artifact were measured.The intensity of twinkling artifact and the contrast-to-noise ratio (C/N ratio) of acoustic shadowing were recorded and all the data was analyzed statistically.Results All the stone phantoms generated twinkling artifact and acoustic shadowing.The difference of the intensity,length and width of twinkling artifact and the C/N ratio of acoustic shadowing had statistically significant each composition (P ＜0.01).There was no overlap between 95％ confidence interval of the intensity of twinkling artifact for any two compositions,and any two compositions of stones could be differentiated by the intensity of twinkling artifact (P ＜0.05).The C/N ratio of acoustic shadowing of calcium oxalate monohydrate and whitlockite stone phantoms were higher than those of hydroxyapatite ones (P ＜0.05).The receiver operating characteristic (ROC) curve displayed that the cutoff value of 1 127 of the intensity of twinkling artifact could be used to diagnose hydroxyapatite stones.The sensitivity,specificity,positive predictive value (PPV),negative predictive value (NPV) and area under the curve (AUC) were 74 ％,68 ％,69.8％,72.3％ and 0.743 respectively.Conclusions Twinkling artifact could be used to differentiate the calcium stones,which will be helpful for clinical treatment.