Publications (18)36.77 Total impact
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Article: Low radiation dose protocol in cardiac CT with 100 kVp: usefulness of display preset optimization.
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ABSTRACT: To evaluate the radiation dose and image quality of 100 kVp cardiac CT, and the effects of display setting optimization. We randomly assigned 100 patients undergoing cardiac CT to one of following two protocols. Fifty patients underwent our conventional protocol with 120 kVp, and the other 50 patients underwent our low radiation dose protocol with 100 kVp. We compared effective dose (ED); CT number, image noise, and contrast noise ratio (CNR) of ascending aorta at 120 and 100 kVp protocol. We also performed quantitative analysis and qualitative analysis for bitmap image of 120, 100 kVp, and display preset optimization for 100 kVp images. The estimated ED was 48 % lower with the 100 kVp protocol than the 120 kVp protocol (2.8 vs. 5.5 mSv, p < 0.01). There is no significant difference in the CNR between 100 and 120 kVp protocol (18.5 ± 3.6 vs. 18.6 ± 3.8, p = 0.84). Display preset optimization significantly improved image quality of 100 kVp cardiac CT, and there is no significant difference in qualitative analysis and quantitative analysis between 100 kVp scan with optimized display preset and 120 kVp scan (p > 0.05). The 100 kVp scanning with optimized display preset offers almost same image quality at cardiac CT of thin adults under 48 % decreased radiation dose.The international journal of cardiovascular imaging 04/2013; · 2.15 Impact Factor -
Article: Novel contrast-injection protocol for coronary computed tomographic angiography: contrast-injection protocol customized according to the patient's time-attenuation response.
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ABSTRACT: We developed a new individually customized contrast-injection protocol for coronary computed tomography (CT) angiography based on the time-attenuation response in a test bolus, and investigated its clinical applicability. We scanned 60 patients with suspected coronary diseases using a 64-detector CT scanner, who were randomly assigned to one of two protocols. In protocol 1 (P1), we estimated the contrast dose to yield a peak aortic attenuation of 400 HU based on the time-attenuation response to a small test-bolus injection (0.3 ml/kg body weight) delivered over 9 s. Then we administered a customized contrast dose over 9 s. In protocol 2 (P2), the dose was tailored to the patient's body weight; this group received 0.7 ml/kg body weight with an injection duration of 9 s. We compared the two protocols for dose of contrast medium, peak attenuation, variations in attenuation values of the ascending aorta, and the success rate of adequate attenuation (250-350 HU) of the coronary arteries. The contrast dose was significantly smaller in P1 than in P2 (36.9 ± 9.2 vs 43.1 ± 7.0 ml, P < 0.01). Peak aortic attenuation was significantly less under P1 than under P2 (384.1 ± 25.0 vs 413.5 ± 45.7, P < 0.01). The mean variation (standard deviation) of the attenuation values was smaller in P1 than in P2 (25.0 vs 45.7, P < 0.01). The success rate of adequate attenuation of the coronary arteries was significantly higher with P1 than with P2 (85.0 vs 65.8 %, P < 0.01). P1 facilitated a reduction in the contrast dose, reduced the individual variations in peak aortic attenuation, and achieved optimal coronary CT attenuation (250-350 HU) more frequently than P2.Heart and Vessels 03/2013; · 2.05 Impact Factor -
Article: Contrast Enhancement During Hepatic Computed Tomography: Effect of Total Body Weight, Height, Body Mass Index, Blood Volume, Lean Body Weight, and Body Surface Area.
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ABSTRACT: OBJECTIVE: The objective of this study was to evaluate the effect of total body weight, height, body mass index, blood volume, lean body weight, and body surface area (BSA) on aortic and hepatic contrast enhancement during hepatic computed tomography (CT). METHODS: We calculated the changes in the CT number per gram of iodine ((Δ Hounsfield units/g [ΔHU/g])) for the aorta and the liver during portal venous phase. We performed linear regression analyses between ΔHU/g and each of the body parameters. RESULTS: ΔHU/g and BSA showed the strongest inverse correlation. The correlation coefficients for the aorta and liver were 0.70 and 0.68 for ΔHU/g and total body weight, 0.41 and 0.37 for height, 0.54 and 0.55 for body mass index, 0.68 and 0.59 for blood volume, 0.70 and 0.62 for lean body weight, and 0.71 and 0.68 for BSA, respectively (P < 0.001 for all). CONCLUSION: Our study supports the use of a protocol with iodine dose adjusted for the patient BSA.Journal of computer assisted tomography 03/2013; 37(2):159-164. · 1.38 Impact Factor -
Article: Low-Contrast Dose Protection Protocol for Diagnostic Computed Tomography in Patients at High-Risk for Contrast-Induced Nephropathy.
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ABSTRACT: OBJECTIVE: To evaluate the safety of a low-contrast dose computed tomography (CT) protocol for patients with renal insufficiency for contrast-induced nephropathy. METHODS: One hundred forty-three patients with renal insufficiency who underwent low-contrast dose-enhanced abdominal CT were reviewed. Another group of 327 patients who received unenhanced CT was reviewed as a control group. Baseline serum creatinine and estimated glomerular filtration rate (eGFR) levels were obtained for all patients to determine the contrast dosing (1.6 and 1.0 mL/kg for patients with eGFR levels 30-59 and 15-29). We compared the incidence of acute kidney injury between the groups. RESULTS: There were no significant differences in the incidence of acute kidney injury between the low-contrast dose and unenhanced CT protocols (9.1% vs 8.3%, P = 0.77). None of the patients with renal dysfunction required postprocedure dialysis. CONCLUSION: The low-contrast dose CT protocol might enable us to perform a contrast-enhanced study without any major safety concerns.Journal of computer assisted tomography 03/2013; 37(2):289-296. · 1.38 Impact Factor -
Article: Radiofrequency ablation combined with transarterial chemoembolization for intermediate hepatocellular carcinoma.
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ABSTRACT: AIM: Radiofrequency ablation therapy (RFA) combined with transarterial chemoembolization (TACE) (combination therapy) is effective for early-stage hepatocellular carcinoma (HCC). The aim of this study was to compare the long-term effects of combination therapy with supportive care alone for intermediate HCC. METHODS: The study included 58 patients with intermediate HCC who received combination therapy (n = 34) or supportive care alone (n = 24). The inclusion criteria were a single nodule of more than 50 mm in diameter or two to three nodules, each measuring more than 30 mm in diameter, or more than three nodules, no vascular invasion and no extrahepatic metastasis. RESULTS: The overall survival rates at 1, 2, 3 and 5 years of the combination therapy group (91%, 65%, 53% and 27%, respectively) were significantly better (P < 0.0001) than those of the supportive care group (42%, 8%, 8% and 0%, respectively). Multivariate analysis identified treatment modality (combination therapy vs supportive care alone: P < 0.0001, risk ratio [RR] = 4.290 [95% confidence interval [CI] = 2.157-8.529]) and serum α-fetoprotein (P = 0.017, RR = 2.318 [95% CI = 1.166-4.610]) as independent and significant factors of overall survival. CONCLUSION: The combination of TACE and RFA is a safe and effective therapy in patients with intermediate HCC.Hepatology Research 02/2013; · 2.20 Impact Factor -
Article: MR diagnosis of vertebral artery dissection: value of 3D time-of-flight and true fast imaging with steady-state precession fusion imaging.
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ABSTRACT: OBJECTIVES: We hypothesized that 3D time-of-flight (TOF) and true fast imaging with steady-state precession (true-FISP) fusion imaging could provide more information regarding the arterial vessel wall. The purpose of this study was to compare the accuracy of lesion detection and the diagnostic confidence of VAD between TOF images alone and fused TOF and true-FISP images. METHODS: Fifty patients were studied: 17 had VAD and 33 had vertebral artery hypoplasia. Fusion images of the vertebral artery were reconstructed using a workstation. A receiver-operating characteristic (ROC) analysis was conducted with a continuous rating scale from 1 to 100 to compare observer performance in VAD detection. Five radiologists participated in the observer performance test, and their performances with TOF images were compared with those using fused images. RESULT: The observers found that the mean areas under the best-fit ROC curve for TOF images alone and fused TOF images were 0.66 ± 0.05 and 0.93 ± 0.04, which were significantly different (P < 0.01). CONCLUSION: The fusion images provided more information regarding the arterial vessel wall. Fused images aided distinction between vertebral artery dissection versus vertebral artery hypoplasia. KEY POINTS : • New MR techniques can help to differentiate flowing blood from static blood products. • Fused TOF and true-FISP images differentiate the lumen and the arterial wall, improving diagnostic performance. • Fused images may be superior to time-of-flight MR angiography alone.Insights into imaging. 12/2012; -
Article: Compact-bolus dynamic CT protocol with a test bolus technique in 64-MDCT coronary angiography: comparison of fixed injection rate and duration protocol.
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ABSTRACT: PURPOSE: We compared the fixed injection rate protocol (P2) with the fixed injection duration protocol (P1) for coronary CT angiography using the test bolus technique. MATERIALS AND METHODS: We randomly assigned 100 patients to one of two protocols. In P1, they received 0.7 mL/kg Iohexol-350 in an injection duration of 9 s, and we selected a delay of 3 s after peak enhancement of test bolus scan. In P2, they received 0.7 mL/kg Iohexol-350 at an injection rate of 5 mL/s, and we selected a delay after peak enhancement of test bolus scan using the following formula: TID/2-2 s, where TID is the injection duration of full bolus. We compared attenuation values in the ascending aorta and coronary arteries and patient-to-patient enhancement variability at each segment. RESULTS: At all segments, CT attenuations of P2 were significantly greater than those of P1 (ascending aorta 400 ± 64 vs. 368 ± 60, P = 0.01; left main trunk 399 ± 67 vs. 369 ± 55, P = 0.02; proximal-RCA 393 ± 66 vs. 363 ± 56, P = 0.01). There was no significant difference in patient-to-patient enhancement variability at all segments between the two groups (P > 0.05). CONCLUSION: P2 yielded superior vessel enhancement and comparable patient-to-patient enhancement variability compared with P1 in thin patients.Japanese journal of radiology 11/2012; · 0.65 Impact Factor -
Article: Low contrast- and low radiation dose protocol for cardiac CT of thin adults at 256-row CT: usefulness of low tube voltage scans and the hybrid iterative reconstruction algorithm.
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ABSTRACT: To evaluate the effect on image quality of a low contrast and radiation dose protocol for cardiac computed tomography (CT) using a low tube voltage, the hybrid-iterative reconstruction algorithm, and a 256-row CT scanner. Before clinical study, we performed phantom experiments to evaluate the hybrid iterative reconstruction technique. We randomly assigned 68 patients undergoing cardiac CT to one of two protocols; 33 were scanned with our conventional 120 kVp protocol, the contrast material (370 mgI/kg body weight) was delivered over 15 s. The other 35 patients underwent scanning at a tube voltage of 80 kVp; the contrast dose, reduced by 50 % (185 mgI/kg), was delivered at the same fractional dose (24.7 mgI/kg/s). The 80 kVp images were post-processed with the 60 % hybrid-iterative reconstruction technique. We evaluated the effective dose (ED), image noise, mean attenuation, and contrast-to-noise ratio (CNR) of each protocol. The hybrid-iterative reconstruction technique offers almost same spatial resolution and noise-power-spectrum curve as compared with filtered back projection reconstruction. There were no decrease in spatial resolution and no shift of spatial frequency in noise power spectrum. The average ED was 74 % lower with the 80- than the 120 kVp protocol (1.4 vs 5.4 mSv). Dunnett's test showed that there were no significant differences in the image noise, mean attenuation, and CNR between hybrid-iterative-reconstructed 80 kVp scans and 120 kVp scans (28.6 ± 6.5 vs 25.3 ± 4.5, p = 0.18; 475.0 HU ± 87.0 vs 445.3 HU ± 67.7, p = 0.20; 17.1 HU ± 3.5 vs 17.8 HU ± 3.1, p = 0.53). The low kVp scan and hybrid-iterative reconstruction algorithm can dramatically decrease the radiation dose and contrast dose with adequate image quality at cardiac CT of thin adults using a 256-row CT scanner.The international journal of cardiovascular imaging 11/2012; · 2.15 Impact Factor -
Article: Successful conservative treatment of pneumatosis intestinalis associated with intraperitoneal free air: report of a case.
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ABSTRACT: While pneumatosis intestinalis (PI) is a rare condition associated with a wide variety of underlying diseases, PI with intraperitoneal free air and ascites is extremely uncommon and is difficult to distinguish from diffuse peritonitis. We herein describe the case of an 87-year-old male who was admitted to our hospital with abdominal pain, distension and nausea. Abdominal plain radiography and computed tomography revealed intramural air collection in the entire intestine, intraperitoneal free air and ascites. Although we first suspected bowel necrosis and perforation, his physical findings and the properties of the diagnostic abdominal paracentesis did not support this diagnosis. Therefore, we selected conservative management, and the intramural air, intraperitoneal free air and ascites disappeared 1 week later. Recognition of the possible presence of non-surgical PI and intraperitoneal free air, although it is extremely rare, is important to avoid a misdiagnosis and the associated unnecessary surgical intervention.Surgery Today 06/2012; 42(10):992-6. · 1.22 Impact Factor -
Article: Low contrast agent and radiation dose protocol for hepatic dynamic CT of thin adults at 256-detector row CT: effect of low tube voltage and hybrid iterative reconstruction algorithm on image quality.
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ABSTRACT: To evaluate the effect on image quality of a low contrast agent dose and radiation dose protocol at abdominal dynamic computed tomography (CT) with a low tube voltage, hybrid iterative reconstruction algorithm, and a 256- detector row scanner. This prospective study received institutional review board approval, and prior informed written consent was obtained from all patients. Seventy-four patients undergoing hepatic dynamic CT were randomly assigned to one of two protocols: Thirty-nine patients underwent scanning with the conventional 120-kVp protocol and the other 35 patients underwent scanning with an 80-kVp tube voltage and a 40% reduction in contrast agent dose. The 80-kVp images were also postprocessed with a hybrid iterative reconstruction algorithm. The estimated effective radiation dose of each protocol was compared and the image noise and contrast-to-noise-ratio (CNR) of the 120-kVp, 80-kVp, and hybrid iterative reconstructed 80-kVp images were evaluated by using the Student t test. The effective radiation dose was 51% lower during the hepatic arterial phase (HAP) and 48% lower during the portal venous phase (PVP) with the 80-kVp protocol than with the 120-kVp protocol (HAP: 5.6 mSv ± 1.0 [standard deviation] vs 11.6 mSv ± 3.3; PVP: 5.8 mSv ± 0.7 vs 11.2 mSv ± 3.2, respectively). The hybrid iterative reconstruction decreased image noise by 23% during the HAP (9.2 ± 1.9 vs 12.0 ± 2.6) and by 24% during the PVP (9.4 ± 1.8 vs 12.3 ± 2.6). There were no significant differences in the CNR of any of the regions of interest between 80-kVp with iterative reconstruction and 120-kVp protocols (P = .46-.85). A low tube voltage and the hybrid iterative reconstruction algorithm can dramatically decrease radiation and contrast agent doses with adequate image quality at hepatic dynamic CT of thin adults with use of a 256-detector row scanner.Radiology 05/2012; 264(2):445-54. · 5.73 Impact Factor -
Article: Resectable gallbladder cancer presenting with acute pancreatitis caused by hemobilia
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ABSTRACT: A 79-year-old female was transferred to our hospital because of suspicion that her acute pancreatitis was caused by stone impaction in the common bile duct (CBD). Laboratory examination showed aspartate aminotransferase, 1645U/l; alanine aminotransferase, 476U/l; amylase, 1365U/l; and white blood cells, 10700/μl. Computed tomography (CT) showed an enhanced tumor in the neck of the gallbladder, an abnormal CBD filled with a high-density area, and localized swelling in the head of the pancreas. Magnetic resonance cholangiopancreatography also showed a low-intensity area in the CBD. Endoscopic retrograde cholangiopancreatography showed coagulated blood discharged from the papilla of Vater. The diagnosis was acute pancreatitis caused by impaction of coagulated blood from a gallbladder tumor. A curative operation was performed 10days after endoscopic bile duct drainage. Gallbladder cancer (GBCa) has no special symptoms and is usually diagnosed at an advanced stage; however, hemobilia and acute pancreatitis are unusual as an initial presentation of GBCa. KeywordsGallbladder cancer–Hemobilia–Acute pancreatitisClinical Journal of Gastroenterology 04/2012; 4(5):336-339. -
Article: Abdominal dynamic CT in patients with renal dysfunction: contrast agent dose reduction with low tube voltage and high tube current-time product settings at 256-detector row CT.
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ABSTRACT: To evaluate the feasibility of a low-contrast agent dose protocol at abdominal dynamic computed tomography (CT) with a low tube voltage high tube current-time product technique and a 256-detector row CT unit. This prospective study received institutional review board approval; written informed consent to participate was obtained from all patients. The study included 151 patients; 117 had an estimated glomerular filtration rate (eGFR) greater than or equal to 60 mL/min/1.73 m(2). These patients were examined with the conventional 120-kVp protocol. The other 34 patients underwent scanning with an 80-kVp tube voltage, a high tube current-time product, and a 40% reduction in contrast agent dose. Effective dose (ED), image noise, attenuation, contrast-to-noise ratio (CNR), and figure of merit of the aorta in the arterial phase and of the portal vein and hepatic parenchyma in the portal venous phase in the two groups were compared with the Student t test. Estimated ED was about 20% lower with the 80-kVp protocol than with the 120-kVp protocol. There were no significant differences in CNR in any region of interest between the 80-kVp protocol and the 120-kVp protocol (abdominal aorta: 36.9 ± 9.7 [standard deviation] vs 36.1 ± 8.1, P = .63; portal vein: 13.4 ± 3.2 vs 13.1 ± 3.2, P = .65; hepatic parenchyma: 6.4 ± 2.6 vs 6.7 ± 2.3, P = .51). Contrast dose at hepatic dynamic 256-detector row CT in patients with renal dysfunction can be decreased by 40% with this protocol by using the 80-kVp setting and a high tube current-time product.Radiology 08/2011; 261(2):467-76. · 5.73 Impact Factor -
Article: Low-kilovoltage, high-tube-current MDCT of liver in thin adults: pilot study evaluating radiation dose, image quality, and display settings.
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ABSTRACT: The purpose of our study was to evaluate the effect of a low tube voltage-high tube current-time product technique for portal phase abdominal CT of thin adults. This study included 25 patients who had undergone portal phase abdominal CT at 120 kVp in the preceding 6 months. All were scanned using 80 kVp and high tube-current time products. We assessed the estimated effective dose (ED), image noise, attenuation, contrast-to-noise ratio (CNR), and figure of merit of the liver and portal vein. Two radiologists evaluated the quality of scans for image contrast and streak artifacts at 80 kVp, 120 kVp, and 80 kVp with wide window width display presets (W-80). The estimated ED was 33% lower at 80 than at 120 kVp. CNR of the portal vein was 36.8% higher at 80 than 120 kVp, and for the liver it was 17.7% higher at 80 than 120 kVp. The visual score of image contrast was significantly higher for W-80 than for 120 kVp; however, there was no significant difference in the visual score of streak artifacts. At portal phase abdominal CT, 80 kVp and a high tube current-time product setting significantly improved image quality and reduced the radiation dose compared with 120 kVp.American Journal of Roentgenology 06/2011; 196(6):1332-8. · 2.78 Impact Factor -
Article: Clinical trial: comparison of alendronate and alfacalcidol in glucocorticoid-associated osteoporosis in patients with ulcerative colitis.
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ABSTRACT: Bone loss is often observed in patients with ulcerative colitis, particularly if they require glucocorticoids. To determine whether the bisphosphonate, alendronate, is safe and effective in preserving bone mass compared to the active vitamin D3, alfacalcidol, in ulcerative colitis patients receiving glucocorticoids. Thirty-nine patients with ulcerative colitis and treated with glucocorticoids were randomized to receive alendronate (5 mg/day) or alfacalcidol (1 microg/day) daily for 12 months. Loss of bone mass was evaluated by bone mineral density, bone resorption by urinary N-telopeptide for type I collagen, and bone formation by serum bone alkaline phosphatase. Alendronate, but not alfacalcidol, significantly increased bone mineral density in the lumbar spine. Alendronate decreased serum bone alkaline phosphatase levels, but alfacalcidol did not. Urinary N-telopeptide for type I collagen levels decreased in both groups, but were significantly lower in the alendronate group. There were no significant differences in the adverse events in the two groups. Our study indicates that alendronate is a safe, well-tolerated and more effective therapy than alfacalcidol for preventing glucocorticoid-associated bone loss in patients with ulcerative colitis.Alimentary Pharmacology & Therapeutics 12/2008; 29(4):424-30. · 3.77 Impact Factor -
Article: A decrease in AFP level related to administration of interferon in patients with chronic hepatitis C and a high level of AFP.
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ABSTRACT: It is known that there is a very high incidence of hepatocellular carcinoma (HCC) among patients with type C chronic hepatitis and cirrhosis, and alpha -fetoprotein (AFP) has been widely used as a diagnostic marker for HCC. However, there are some patients showing continuous high AFP values but no evidence of HCC, and some studies have defined such patients as a high-risk group for HCC. In vitro study has shown that interferon (IFN) inhibits cell proliferation and enhances apoptosis as well as specific cytotoxic T lymphocytes against HCC, resulting in direct anticancer actions. In this study, we investigated the effect of IFN on AFP changes in chronic hepatitis C patients. Of 40 patients with chronic hepatitis C in whom diagnostic imaging confirmed the absence of HCC, 24 patients showed high pretreatment AFP values (high AFP group: AFP level > 10 ng/dl; mean +/- SD, 46.3 +/- 41.5 ng/dl) and 16 showed low pretreatment AFP values (low AFP group: pretreatment AFP level < or = 10 ng/dl; mean +/- SD, 5.3 +/- 2.2 ng/dl). Pretreatment clinical parameters were statistically evaluated in relation to the AFP value. In the high AFP group, the platelet count, albumin level, and prothrombin (%) were significantly lower (P = 0.047, P = 0.0002, and P = 0.044, respectively), suggesting that AFP value increases with advancing liver disease. Subsequently 27 patients were administered IFN (IFN group), and the remaining 13 patients were administered Stronger Neo-minophagen C (SNMC), a glycyrrhizin preparation (SNMC group), as a control group receiving liver-protective therapy. Alanine aminotransferase was reduced in both the IFN and the SNMC group (mean, 132.56 to 60.07 mg/ml [P < 0001] and 147.85 to 56.23 mg/ml [P = 0.0240], respectively). AFP was significantly reduced in the IFN group (mean, 30.03 to 12.65 ng/ml; P = 0.0034), but there was no significant change in AFP in the SNMC group (mean, 29.70 to 39.17 ng/ml). AFP is useful for diagnosing HCC; however, some patients show a persistently high AFP level in the absence of HCC, and these patients have been described as a high-risk group for HCC. In this study, we found that IFN therapy but not SNMC universally reduced the AFP baseline. Since AFP is a significant predictor for HCC, therapeutic strategies for hepatitis C, e.g., long-term low-dose IFN treatment, may reduce hepatocarcinogenesis.Digestive Diseases and Sciences 05/2006; 51(4):808-12. · 2.12 Impact Factor -
Article: [A case of respiratory failure caused by pulmonary alveolar hemorrhage in Crohn's disease].
Nippon Shokakibyo Gakkai zasshi The Japanese journal of gastro-enterology 05/2004; 101(4):397-402. -
Article: Shock index correlates with extravasation on angiographs of gastrointestinal hemorrhage: a logistics regression analysis.
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ABSTRACT: We applied multivariate analysis to the clinical findings in patients with acute gastrointestinal (GI) hemorrhage and compared the relationship between these findings and angiographic evidence of extravasation. Our study population consisted of 46 patients with acute GI bleeding. They were divided into two groups. In group 1 we retrospectively analyzed 41 angiograms obtained in 29 patients (age range, 25-91 years; average, 71 years). Their clinical findings including the shock index (SI), diastolic blood pressure, hemoglobin, platelet counts, and age, which were quantitatively analyzed. In group 2, consisting of 17 patients (age range, 21-78 years; average, 60 years), we prospectively applied statistical analysis by a logistics regression model to their clinical findings and then assessed 21 angiograms obtained in these patients to determine whether our model was useful for predicting the presence of angiographic evidence of extravasation. On 18 of 41 (43.9%) angiograms in group 1 there was evidence of extravasation; in 3 patients it was demonstrated only by selective angiography. Factors significantly associated with angiographic visualization of extravasation were the SI and patient age. For differentiation between cases with and cases without angiographic evidence of extravasation, the maximum cutoff point was between 0.51 and 0.0.53. Of the 21 angiograms obtained in group 2, 13 (61.9%) showed evidence of extravasation; in 1 patient it was demonstrated only on selective angiograms. We found that in 90% of the cases, the prospective application of our model correctly predicted the angiographically confirmed presence or absence of extravasation. We conclude that in patients with GI hemorrhage, angiographic visualization of extravasation is associated with the pre-embolization SI. Patients with a high SI value should undergo study to facilitate optimal treatment planning.CardioVascular and Interventional Radiology 30(5):861-5. · 2.09 Impact Factor -
Article: A low-kilovolt (peak) high-tube current technique improves venous enhancement and reduces the radiation dose at indirect multidetector-row CT venography: initial experience.
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ABSTRACT: The purpose was to evaluate the image noise, contrast-to-noise ratio, and radiation dose at indirect multidetector-row computed tomographic venography (CTV) using a low-kilovolt (peak) (kV[p]) high-tube current technique. Thirty patients underwent indirect CTV of the lower extremity at 120 kV(p) with 170 mA and at 80 kV(p) with 426 mA (CT dose index volumes 11.8 and 9.0 mGy, respectively) on a 64-detector CT scanner. We assessed CT numbers, image noise, and contrast-to-noise ratio of deep (femoral and popliteal) veins. The mean (SD) CT numbers of the femoral and popliteal veins were significantly greater at 80 kV(p) than at 120 kV(p) (142.8 [24.5] and 147.0 [19.4] Hounsfield units [HU], respectively, vs 93.1 [15.5] and 105.0 [14.9] HU, respectively; P < 0.01). The mean (SD) image noise was significantly higher at 80 kV(p) than at 120 kV(p) (11.6 [2.6] and 7.4 [1.4] HU, respectively, vs 8.9 [1.6] and 6.2 [1.5] HU, respectively; P < 0.01). Contrast-to-noise ratios at the femoral and popliteal veins were significantly higher at 80 kV(p) than at 120 kV(p) (6.0 [2.2] and 9.7 [2.4], respectively vs 3.3 [1.8] and 6.9 [2.5], respectively; P < 0.01). At indirect CTV, 80 kV(p) and a high tube current setting yielded significantly improved image quality at a reduced radiation dose compared with 120 kV(p).Journal of computer assisted tomography 35(1):141-7. · 1.38 Impact Factor
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2013
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Kumamoto University
Kumamoto-shi, Kumamoto Prefecture, Japan
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2004
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Kurume University
- Department of Gastroenterology
Kurume, Fukuoka-ken, Japan
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