- Email: [email protected]
PD36-02 DIAGNOSTIC PERFORMANCE OF LOW-DOSE NON ENHANCE CT WITH ITERATIVE RECONSTRUCTION IN DIAGNOSIS OF UROLITHIASIS
THE JOURNAL OF UROLOGYâ
e902
135kV and 80kV was calculated. The result showed a definite corre0 HU(135kV)0 ¼0.6700 HU(80kV)0 lation as demonstrated by (R2¼0.970) for calcium oxalate monohydrate and 0 HU(135kV)0 ¼ 1.0490 HU(80kV)0 (R2¼0.989) for uric acid. CONCLUSIONS: DE imaging can make a material decomposition by applying two different energy sources. Based on the results, it is possible to know the stone composition, such as uric acid and calcium containing stones, by DE-CT before intervention. If we could make a definitive diagnosis of uric acid stone for the patient with severe complication, such as cardiovascular disease, the patient would receive stone dissolution therapy by urine alkalization. DE-CT will be useful for not only estimation of stone fragility and stone skin distance but also prediction of stone composition.
Vol. 191, No. 4S, Supplement, Tuesday, May 20, 2014
agreement of LDCT-IR between the two reviewers was high with kappa values ranging from 0.901 to 1.000 in all groups. Objective image noise was higher on LDCT-IR (p<0.01), but no significant differences of subjective noise was found. CONCLUSIONS: LDCT-IR showed significant radiation reduction while maintaining image quality as an attractive option in urologic perspective to diagnosis of urinary stones. Source of Funding: none
PD36-03 WITHDRAWN EFFICACY OF LOW DOSE NONENHANCED ABDOMINOPELVIC COMPUTED TOMOGRAPHY WITH ITERATIVE RECONSTRUCTION IN DIAGNOSIS OF UROLITHIASIS Jung Won Choe, Kyung Do Kim, Young Tae Moon, Jong Kyou Kwon, In Ho Chang, Jung Hoon Kim, Jae Duck Choi, Seung Hyun Ahn, Min Su Kim, Seoul, Korea, Republic of; So Yeon Lee, Goyang-si, Gyeonggi-do, Korea, Republic of; Jae Hyung Ryu, Sang Ho Park*, Seoul, Korea, Republic of
PD36-04 RENAL PERCUTANEOUS ACCESS WITH THE URO DYNA-CT Fabio Torricelli, Khaled Fareed, Gordon McLennan, Shubha De*, Manoj Monga, Cleveland, OH Source of Funding: none
PD36-02 DIAGNOSTIC PERFORMANCE OF LOW-DOSE NON ENHANCE CT WITH ITERATIVE RECONSTRUCTION IN DIAGNOSIS OF UROLITHIASIS Jung Won Choe, Kyung Do Kim, Young Tae Moon, Jong Kyou Kwon*, In Ho Chang, Jung Hoon Kim, Jae Duck Choi, Seung Hyun Ahn, Min Su Kim, Seoul, Korea, Republic of; So Yeon Lee, Goyang-si, Gyeonggi-do, Korea, Republic of; Jae Hyung Ryu, Sang Ho Park, Seoul, Korea, Republic of INTRODUCTION AND OBJECTIVES: Low-dose CT(LDCT) is a promising option for diagnosing urinary stones, but it can substantially increase image noise. We evaluated the efficacy of iterative reconstruction(IR) technique for reducing image noises on LDCT and the diagnostic performances especially in urologic perspective. METHODS: 197 stones from 119 patients who performed nonenhanced CT with both standard dose and LDCT with IR(LDCT-IR) were enrolled. Interpretations were performed in the two scans for stone characteristics(size, volume, location, house field unit(HU), skin-tostone distance(SSD)), radiation(dose-length product(DLP), effective dose(ED)), image noise(objective, subjective). Inter-observer agreements were assessed between urologist and radiologist with kappa analysis. All comparisons were performed after dividing all stones into 3 groups; all size, larger than 3mm and less than 3mm. RESULTS: No statistical differences were found in stone characteristics between the two scans except HU in all size group. The average DLP and ED were 394.94mGy and 5.92mSv in CCT, and 92.88mGy and 1.39mSv in LDCT-IR, respectively. The average dose reduction was 76.6%(p<0.001). In the LDCT-IR, the sensitivity, specificity, positive predictive value, negative predictive value, accuracy for the urologist and radiologist reviewer have no significant differences for diagnosing stones of larger than 3 mm (p >0.05). Inter-observer
INTRODUCTION AND OBJECTIVES: Percutaneous nephrolitothomy (PCNL) is the gold standard for surgical management of renal stones >2cm. Renal access may be challenging in cases of complex renal anatomy or large stone burden (i.e. complete staghorn calculi). Herein, we present percutaneous renal access using an Uro Dyna-CT (Siemens Healthcare Solutions, Germany), for high-quality 3-dimensional real-time imaging. METHODS: Review of an index patient: 50y/o male presenting with a right partial staghorn and proximal ureteric stone. RESULTS: Electing to undergo PCNL, he was referred to radiology for pre-op percutaneous renal access. Two attempts for upper/middle pole NT placement were made (to simultaneously treat lower pole and ureteric stones), however due to the plural reflection and overlying liver a safe puncture tract could not be established. A Uro Dyna-CT was performed by correlating real time fluoroscopic imaging to a simultaneous on-table axial CT scan (Figures 2-3). Delineating a safe window, right middle pole access allowed subsequent PCNL to be performed successfully. CONCLUSIONS: In select patients, the Uro Dyna-CT adds simultaneous detailed anatomic imaging to fluoroscopic renal access to improve successful puncture, and reduce potential morbidities.
Source of Funding: none
e902
135kV and 80kV was calculated. The result showed a definite corre0 HU(135kV)0 ¼0.6700 HU(80kV)0 lation as demonstrated by (R2¼0.970) for calcium oxalate monohydrate and 0 HU(135kV)0 ¼ 1.0490 HU(80kV)0 (R2¼0.989) for uric acid. CONCLUSIONS: DE imaging can make a material decomposition by applying two different energy sources. Based on the results, it is possible to know the stone composition, such as uric acid and calcium containing stones, by DE-CT before intervention. If we could make a definitive diagnosis of uric acid stone for the patient with severe complication, such as cardiovascular disease, the patient would receive stone dissolution therapy by urine alkalization. DE-CT will be useful for not only estimation of stone fragility and stone skin distance but also prediction of stone composition.
Vol. 191, No. 4S, Supplement, Tuesday, May 20, 2014
agreement of LDCT-IR between the two reviewers was high with kappa values ranging from 0.901 to 1.000 in all groups. Objective image noise was higher on LDCT-IR (p<0.01), but no significant differences of subjective noise was found. CONCLUSIONS: LDCT-IR showed significant radiation reduction while maintaining image quality as an attractive option in urologic perspective to diagnosis of urinary stones. Source of Funding: none
PD36-03 WITHDRAWN EFFICACY OF LOW DOSE NONENHANCED ABDOMINOPELVIC COMPUTED TOMOGRAPHY WITH ITERATIVE RECONSTRUCTION IN DIAGNOSIS OF UROLITHIASIS Jung Won Choe, Kyung Do Kim, Young Tae Moon, Jong Kyou Kwon, In Ho Chang, Jung Hoon Kim, Jae Duck Choi, Seung Hyun Ahn, Min Su Kim, Seoul, Korea, Republic of; So Yeon Lee, Goyang-si, Gyeonggi-do, Korea, Republic of; Jae Hyung Ryu, Sang Ho Park*, Seoul, Korea, Republic of
PD36-04 RENAL PERCUTANEOUS ACCESS WITH THE URO DYNA-CT Fabio Torricelli, Khaled Fareed, Gordon McLennan, Shubha De*, Manoj Monga, Cleveland, OH Source of Funding: none
PD36-02 DIAGNOSTIC PERFORMANCE OF LOW-DOSE NON ENHANCE CT WITH ITERATIVE RECONSTRUCTION IN DIAGNOSIS OF UROLITHIASIS Jung Won Choe, Kyung Do Kim, Young Tae Moon, Jong Kyou Kwon*, In Ho Chang, Jung Hoon Kim, Jae Duck Choi, Seung Hyun Ahn, Min Su Kim, Seoul, Korea, Republic of; So Yeon Lee, Goyang-si, Gyeonggi-do, Korea, Republic of; Jae Hyung Ryu, Sang Ho Park, Seoul, Korea, Republic of INTRODUCTION AND OBJECTIVES: Low-dose CT(LDCT) is a promising option for diagnosing urinary stones, but it can substantially increase image noise. We evaluated the efficacy of iterative reconstruction(IR) technique for reducing image noises on LDCT and the diagnostic performances especially in urologic perspective. METHODS: 197 stones from 119 patients who performed nonenhanced CT with both standard dose and LDCT with IR(LDCT-IR) were enrolled. Interpretations were performed in the two scans for stone characteristics(size, volume, location, house field unit(HU), skin-tostone distance(SSD)), radiation(dose-length product(DLP), effective dose(ED)), image noise(objective, subjective). Inter-observer agreements were assessed between urologist and radiologist with kappa analysis. All comparisons were performed after dividing all stones into 3 groups; all size, larger than 3mm and less than 3mm. RESULTS: No statistical differences were found in stone characteristics between the two scans except HU in all size group. The average DLP and ED were 394.94mGy and 5.92mSv in CCT, and 92.88mGy and 1.39mSv in LDCT-IR, respectively. The average dose reduction was 76.6%(p<0.001). In the LDCT-IR, the sensitivity, specificity, positive predictive value, negative predictive value, accuracy for the urologist and radiologist reviewer have no significant differences for diagnosing stones of larger than 3 mm (p >0.05). Inter-observer
INTRODUCTION AND OBJECTIVES: Percutaneous nephrolitothomy (PCNL) is the gold standard for surgical management of renal stones >2cm. Renal access may be challenging in cases of complex renal anatomy or large stone burden (i.e. complete staghorn calculi). Herein, we present percutaneous renal access using an Uro Dyna-CT (Siemens Healthcare Solutions, Germany), for high-quality 3-dimensional real-time imaging. METHODS: Review of an index patient: 50y/o male presenting with a right partial staghorn and proximal ureteric stone. RESULTS: Electing to undergo PCNL, he was referred to radiology for pre-op percutaneous renal access. Two attempts for upper/middle pole NT placement were made (to simultaneously treat lower pole and ureteric stones), however due to the plural reflection and overlying liver a safe puncture tract could not be established. A Uro Dyna-CT was performed by correlating real time fluoroscopic imaging to a simultaneous on-table axial CT scan (Figures 2-3). Delineating a safe window, right middle pole access allowed subsequent PCNL to be performed successfully. CONCLUSIONS: In select patients, the Uro Dyna-CT adds simultaneous detailed anatomic imaging to fluoroscopic renal access to improve successful puncture, and reduce potential morbidities.
Source of Funding: none