The aim of this article is to clarify diagnostic pitfalls of pancreatic serous cystic neoplasm(SCN) that may result in erroneous characterization. Usual and unusual imaging findings of SCN as well as potential SCN mim...The aim of this article is to clarify diagnostic pitfalls of pancreatic serous cystic neoplasm(SCN) that may result in erroneous characterization. Usual and unusual imaging findings of SCN as well as potential SCN mimickers are presented. The diagnostic key of SCN is to look for a cluster of microcysts(honeycomb pattern), which may not be always found in the center. Fibrosis in SCN may be mistaken for a mural nodule of intraductal papillary mucinous neoplasm(IPMN). The absence of cyst wall enhancement may be helpful to distinguish SCN from mucinous cystic neoplasm. However, oligocystic SCN and branch duct type IPMN may morphologically overlap. In addition, solid serous adenoma, an extremely rare variant of SCN, is difficult to distinguish from neuroendocrine tumor.展开更多
AIM: To evaluate the complications and clinical outcomes of transcatheter arterial embolization (TAE) for symptoms related to severe arterioportal fistulas (APFs). METHODS: Six patients (3 males, 3 females; mean age, ...AIM: To evaluate the complications and clinical outcomes of transcatheter arterial embolization (TAE) for symptoms related to severe arterioportal fistulas (APFs). METHODS: Six patients (3 males, 3 females; mean age, 63.8 years; age range, 60-71 years) with chronic liver disease and severe APFs due to percutaneous intrahepatic treatment (n=5) and portal vein (PV) tumor thrombosis of hepatocellular carcinoma (n=1) underwent TAE for symptoms related to severe APFs [refractory ascites (n=4), hemorrhoidal hemorrhage (n=1), and hepatic encephalopathy (n=1)]. Control of symptoms related to APFs and complications were evaluated during the follow-up period (range, 4-57 mo). RESULTS: In all patients, celiac angiography revealed immediate retrograde visualization of the main PV before TAE, indicating severe APF. Selective TAE for the hepatic arteries was performed using metallic coils (MC, n=4) and both MCs and n-butyl cyanoacrylate (n=2). Three patients underwent repeated TAEs for residual APFs and ascites. Four patients developed PV thrombosis after TAE. During the follow-up period after TAE, APF obliteration and symptomatic improvement were obtained in all patients. CONCLUSION: Although TAE for severe APFs may sometimes be complicated by PV thrombosis, TAE can be an effective treatment to improve clinical symptoms related to severe APFs.展开更多
To retrospectively evaluate the diagnostic performance of free-breathing diffusion-weighted imaging (FB-DWI) with modified imaging parameter settings for detecting hepatocellular carcinomas (HCCs). METHODSFifty-one pa...To retrospectively evaluate the diagnostic performance of free-breathing diffusion-weighted imaging (FB-DWI) with modified imaging parameter settings for detecting hepatocellular carcinomas (HCCs). METHODSFifty-one patients at risk for HCC were scanned with both FB-DWI and respiratory-triggered DWI with the navigator echo respiratory-triggering technique (RT-DWI). Qualitatively, the sharpness of the liver contour, the image noise and the chemical shift artifacts on each DWI with b-values of 1000 s/mm<sup>2</sup> were independently evaluated by three radiologists using 4-point scoring. We compared the image quality scores of each observer between the two DWI methods, using the Wilcoxon signed-rank test. Quantitatively, we compared the signal-to-noise ratios (SNRs) of the liver parenchyma and lesion-to-nonlesion contrast-to-noise ratios (CNRs) after measuring the signal intensity on each DWI with a b-factor of 1000 s/mm<sup>2</sup>. The average SNRs and CNRs between the two DWI methods were compared by the paired t-test. The detectability of HCC on each DWI was also analyzed by three radiologists. The detectability provided by the two DWI methods was compared using McNemar’s test. RESULTSFor all observers, the averaged image quality scores of FB-DWI were: Sharpness of the liver contour [observer (Obs)-1, 3.08 ± 0.81; Obs-2, 2.98 ± 0.73; Obs-3, 3.54 ± 0.75], those of the distortion (Obs-1, 2.94 ± 0.50; Obs-2, 2.71 ± 0.70; Obs-3, 3.27 ± 0.53), and the chemical shift artifacts (Obs-1, 3.38 ± 0.60; Obs-2, 3.15 ± 1.07; Obs-3, 3.21 ± 0.85). The averaged image quality scores of RT-DWI were: Sharpness of the liver contour (Obs-1, 2.33 ± 0.65; Obs-2, 2.37 ± 0.74; Obs-3, 2.75 ± 0.81), distortion (Obs-1, 2.81 ± 0.56; Obs-2, 2.25 ± 0.74; Obs-3, 2.96 ± 0.71), and the chemical shift artifacts (Obs-1, 2.92 ± 0.59; Obs-2, 2.21 ± 0.85; Obs-3, 2.77 ± 1.08). All image quality scores of FB-DWI were significantly higher than those of RT-DWI (P < 0.05). The average SNR of the normal liver parenchyma by FB-DWI (11.0 ± 4.8) was not significantly different from that shown by RT-DWI (11.0 ± 5.0); nor were the lesion-to-nonlesion CNRs significantly different (FB-DWI, 21.4 ± 17.7; RT-DWI, 20.1 ± 15.1). For all three observers, the detectability of FB-DWI (Obs-1, 43.6%; Obs-2, 53.6%; and Obs-3, 45.0%) was significantly higher than that of RT-DWI (Obs-1, 29.1%; Obs-2, 43.6%; and Obs-3, 34.5%) (P < 0.05). CONCLUSIONFB-DWI showed better image quality and higher detectability of HCC compared to RT-DWI, without significantly reducing the SNRs of the liver parenchyma and lesion-to-nonlesion CNRs.展开更多
AIM To evaluate the diagnostic performance of computed tomography(CT) volumetry for discriminating the fibrosis stage in patients with nonalcoholic fatty liver disease(NAFLD).METHODS A total of 38 NAFLD patients were ...AIM To evaluate the diagnostic performance of computed tomography(CT) volumetry for discriminating the fibrosis stage in patients with nonalcoholic fatty liver disease(NAFLD).METHODS A total of 38 NAFLD patients were enrolled. On the basis of CT imaging, the volumes of total, left lateral segment(LLS), left medial segment, caudate lobe, and right lobe(RL) of the liver were calculated with a dedicated liver application. The relationship between the volume percentage of each area and fibrosis stage was analyzed using Spearman's rank correlation coefficient. A receiver operating characteristic(ROC) curve analysis was performed to determine the accuracy of CT volumetry for discriminating fibrosis stage.RESULTS The volume percentages of the caudate lobe and the LLS significantly increased with the fibrosis stage(r = 0.815, P < 0.001; and r = 0.465, P = 0.003, respectively). Contrarily, the volume percentage of the RL significantly decreased with fibrosis stage(r =-0.563, P < 0.001). The volume percentage of the caudate lobe had the best diagnostic accuracy for staging fibrosis, and the area under the ROC curve values for discriminating fibrosis stage were as follows: ≥ F1, 0.896; ≥ F2, 0.929; ≥ F3, 0.955; and ≥ F4, 0.923. The best cut-off for advanced fibrosis(F3-F4) was 4.789%, 85.7% sensitivity and 94.1% specificity.CONCLUSION The volume percentage of the caudate lobe calculated by CT volumetry is a useful diagnostic parameter for staging fibrosis in NAFLD patients.展开更多
AIM:To present our initial experience with computed tomography guided radiofrequency ablation(RFA) of osteoid osteoma(OO) in our institution.METHODS:RFA was performed on eight patients(5 males and 3 females) with clin...AIM:To present our initial experience with computed tomography guided radiofrequency ablation(RFA) of osteoid osteoma(OO) in our institution.METHODS:RFA was performed on eight patients(5 males and 3 females) with clinically and radiologically diagnosed OO(femoral neck,n = 4;femoral diaphysis,n = 2;tibial diaphysis,n = 1;fibular diaphysis,n = 1).Ablation was performed using an electrode with a 10-mm exposed tip for a total of 4-6 min at a targeted temperature of 90 degrees Celsius.No cooling system was used.The intervention was accepted as technically successful if the tip of the electrode could be placed within the center of the nidus.We defined clinical success as a disappearance within 2 wk after treatment of symptoms that had manifested at presentation.RESULTS:All procedures were technically successful.No major or immediate complications were observed.Clinical success was achieved in six of eight patients in the first procedure.A second procedure was performed for two patients who had recurrent or continued pain,and one of these cases was successfully treated.The overall rate of success was 87.5%(7/8).No complication was observed.CONCLUSION:Our preliminary results indicate a favorable success rate and no complications and are compatible with the previous reports of RFA of OO.展开更多
Aim:To evaluate the effectiveness of using cone-beam computed tomography(CBCT)in transcatheter arterial chemoembolization(TACE)to detect hapatocellular carcinoma(HCC)nodules and their feeding arteries.Methods:Twenty-f...Aim:To evaluate the effectiveness of using cone-beam computed tomography(CBCT)in transcatheter arterial chemoembolization(TACE)to detect hapatocellular carcinoma(HCC)nodules and their feeding arteries.Methods:Twenty-four patients with HCCs who underwent TACE using CBCT in addition to conventional digital subtraction angiography(DSA)were enrolled.After both conventional DSA and CBCT through the hepatic artery were acquired,TACE were performed.The nodules were defined as an HCC when dense accumulation of iodized oil was found within the nodule on CT obtained 2 weeks after the TACE.The number of detected nodules and identified feeding arteries,and their correlations with anatomical locations were assessed.Results:A total of 39 HCC nodules(tumor diameter,7-40 mm;mean,17.4±7.9 mm)were detected.Thirty-one nodules were detected by DSA alone but 8 nodules were additionally detected by adding CBCT to DSA.There were 53 feeding arteries associated with the 39 HCC nodules.Among these arteries,21 were identified by DSA alone;however,47 were identified by combining CBCT with DSA.Additional feeding arteries,especially for the nodules located at the right and caudate lobes,were identified by CBCT.On the other hand,there was no difference in detection of nodules between the anatomical locations by CBCT.Conclusion:The use of CBCT in addition to DSA offers potential for increasing the number of detected nodules,and the number of their feeding arteries at the right and caudate lobes.CBCT might improve the quality of TACE procedure for HCC than DSA alone.展开更多
文摘The aim of this article is to clarify diagnostic pitfalls of pancreatic serous cystic neoplasm(SCN) that may result in erroneous characterization. Usual and unusual imaging findings of SCN as well as potential SCN mimickers are presented. The diagnostic key of SCN is to look for a cluster of microcysts(honeycomb pattern), which may not be always found in the center. Fibrosis in SCN may be mistaken for a mural nodule of intraductal papillary mucinous neoplasm(IPMN). The absence of cyst wall enhancement may be helpful to distinguish SCN from mucinous cystic neoplasm. However, oligocystic SCN and branch duct type IPMN may morphologically overlap. In addition, solid serous adenoma, an extremely rare variant of SCN, is difficult to distinguish from neuroendocrine tumor.
文摘AIM: To evaluate the complications and clinical outcomes of transcatheter arterial embolization (TAE) for symptoms related to severe arterioportal fistulas (APFs). METHODS: Six patients (3 males, 3 females; mean age, 63.8 years; age range, 60-71 years) with chronic liver disease and severe APFs due to percutaneous intrahepatic treatment (n=5) and portal vein (PV) tumor thrombosis of hepatocellular carcinoma (n=1) underwent TAE for symptoms related to severe APFs [refractory ascites (n=4), hemorrhoidal hemorrhage (n=1), and hepatic encephalopathy (n=1)]. Control of symptoms related to APFs and complications were evaluated during the follow-up period (range, 4-57 mo). RESULTS: In all patients, celiac angiography revealed immediate retrograde visualization of the main PV before TAE, indicating severe APF. Selective TAE for the hepatic arteries was performed using metallic coils (MC, n=4) and both MCs and n-butyl cyanoacrylate (n=2). Three patients underwent repeated TAEs for residual APFs and ascites. Four patients developed PV thrombosis after TAE. During the follow-up period after TAE, APF obliteration and symptomatic improvement were obtained in all patients. CONCLUSION: Although TAE for severe APFs may sometimes be complicated by PV thrombosis, TAE can be an effective treatment to improve clinical symptoms related to severe APFs.
文摘To retrospectively evaluate the diagnostic performance of free-breathing diffusion-weighted imaging (FB-DWI) with modified imaging parameter settings for detecting hepatocellular carcinomas (HCCs). METHODSFifty-one patients at risk for HCC were scanned with both FB-DWI and respiratory-triggered DWI with the navigator echo respiratory-triggering technique (RT-DWI). Qualitatively, the sharpness of the liver contour, the image noise and the chemical shift artifacts on each DWI with b-values of 1000 s/mm<sup>2</sup> were independently evaluated by three radiologists using 4-point scoring. We compared the image quality scores of each observer between the two DWI methods, using the Wilcoxon signed-rank test. Quantitatively, we compared the signal-to-noise ratios (SNRs) of the liver parenchyma and lesion-to-nonlesion contrast-to-noise ratios (CNRs) after measuring the signal intensity on each DWI with a b-factor of 1000 s/mm<sup>2</sup>. The average SNRs and CNRs between the two DWI methods were compared by the paired t-test. The detectability of HCC on each DWI was also analyzed by three radiologists. The detectability provided by the two DWI methods was compared using McNemar’s test. RESULTSFor all observers, the averaged image quality scores of FB-DWI were: Sharpness of the liver contour [observer (Obs)-1, 3.08 ± 0.81; Obs-2, 2.98 ± 0.73; Obs-3, 3.54 ± 0.75], those of the distortion (Obs-1, 2.94 ± 0.50; Obs-2, 2.71 ± 0.70; Obs-3, 3.27 ± 0.53), and the chemical shift artifacts (Obs-1, 3.38 ± 0.60; Obs-2, 3.15 ± 1.07; Obs-3, 3.21 ± 0.85). The averaged image quality scores of RT-DWI were: Sharpness of the liver contour (Obs-1, 2.33 ± 0.65; Obs-2, 2.37 ± 0.74; Obs-3, 2.75 ± 0.81), distortion (Obs-1, 2.81 ± 0.56; Obs-2, 2.25 ± 0.74; Obs-3, 2.96 ± 0.71), and the chemical shift artifacts (Obs-1, 2.92 ± 0.59; Obs-2, 2.21 ± 0.85; Obs-3, 2.77 ± 1.08). All image quality scores of FB-DWI were significantly higher than those of RT-DWI (P < 0.05). The average SNR of the normal liver parenchyma by FB-DWI (11.0 ± 4.8) was not significantly different from that shown by RT-DWI (11.0 ± 5.0); nor were the lesion-to-nonlesion CNRs significantly different (FB-DWI, 21.4 ± 17.7; RT-DWI, 20.1 ± 15.1). For all three observers, the detectability of FB-DWI (Obs-1, 43.6%; Obs-2, 53.6%; and Obs-3, 45.0%) was significantly higher than that of RT-DWI (Obs-1, 29.1%; Obs-2, 43.6%; and Obs-3, 34.5%) (P < 0.05). CONCLUSIONFB-DWI showed better image quality and higher detectability of HCC compared to RT-DWI, without significantly reducing the SNRs of the liver parenchyma and lesion-to-nonlesion CNRs.
基金Supported by a Grant-in-in-Aid for Scientific Research(C)(No26461796) from the Japanese Ministry of Education,Culture,Sports,Science,and Technology
文摘AIM To evaluate the diagnostic performance of computed tomography(CT) volumetry for discriminating the fibrosis stage in patients with nonalcoholic fatty liver disease(NAFLD).METHODS A total of 38 NAFLD patients were enrolled. On the basis of CT imaging, the volumes of total, left lateral segment(LLS), left medial segment, caudate lobe, and right lobe(RL) of the liver were calculated with a dedicated liver application. The relationship between the volume percentage of each area and fibrosis stage was analyzed using Spearman's rank correlation coefficient. A receiver operating characteristic(ROC) curve analysis was performed to determine the accuracy of CT volumetry for discriminating fibrosis stage.RESULTS The volume percentages of the caudate lobe and the LLS significantly increased with the fibrosis stage(r = 0.815, P < 0.001; and r = 0.465, P = 0.003, respectively). Contrarily, the volume percentage of the RL significantly decreased with fibrosis stage(r =-0.563, P < 0.001). The volume percentage of the caudate lobe had the best diagnostic accuracy for staging fibrosis, and the area under the ROC curve values for discriminating fibrosis stage were as follows: ≥ F1, 0.896; ≥ F2, 0.929; ≥ F3, 0.955; and ≥ F4, 0.923. The best cut-off for advanced fibrosis(F3-F4) was 4.789%, 85.7% sensitivity and 94.1% specificity.CONCLUSION The volume percentage of the caudate lobe calculated by CT volumetry is a useful diagnostic parameter for staging fibrosis in NAFLD patients.
文摘AIM:To present our initial experience with computed tomography guided radiofrequency ablation(RFA) of osteoid osteoma(OO) in our institution.METHODS:RFA was performed on eight patients(5 males and 3 females) with clinically and radiologically diagnosed OO(femoral neck,n = 4;femoral diaphysis,n = 2;tibial diaphysis,n = 1;fibular diaphysis,n = 1).Ablation was performed using an electrode with a 10-mm exposed tip for a total of 4-6 min at a targeted temperature of 90 degrees Celsius.No cooling system was used.The intervention was accepted as technically successful if the tip of the electrode could be placed within the center of the nidus.We defined clinical success as a disappearance within 2 wk after treatment of symptoms that had manifested at presentation.RESULTS:All procedures were technically successful.No major or immediate complications were observed.Clinical success was achieved in six of eight patients in the first procedure.A second procedure was performed for two patients who had recurrent or continued pain,and one of these cases was successfully treated.The overall rate of success was 87.5%(7/8).No complication was observed.CONCLUSION:Our preliminary results indicate a favorable success rate and no complications and are compatible with the previous reports of RFA of OO.
文摘Aim:To evaluate the effectiveness of using cone-beam computed tomography(CBCT)in transcatheter arterial chemoembolization(TACE)to detect hapatocellular carcinoma(HCC)nodules and their feeding arteries.Methods:Twenty-four patients with HCCs who underwent TACE using CBCT in addition to conventional digital subtraction angiography(DSA)were enrolled.After both conventional DSA and CBCT through the hepatic artery were acquired,TACE were performed.The nodules were defined as an HCC when dense accumulation of iodized oil was found within the nodule on CT obtained 2 weeks after the TACE.The number of detected nodules and identified feeding arteries,and their correlations with anatomical locations were assessed.Results:A total of 39 HCC nodules(tumor diameter,7-40 mm;mean,17.4±7.9 mm)were detected.Thirty-one nodules were detected by DSA alone but 8 nodules were additionally detected by adding CBCT to DSA.There were 53 feeding arteries associated with the 39 HCC nodules.Among these arteries,21 were identified by DSA alone;however,47 were identified by combining CBCT with DSA.Additional feeding arteries,especially for the nodules located at the right and caudate lobes,were identified by CBCT.On the other hand,there was no difference in detection of nodules between the anatomical locations by CBCT.Conclusion:The use of CBCT in addition to DSA offers potential for increasing the number of detected nodules,and the number of their feeding arteries at the right and caudate lobes.CBCT might improve the quality of TACE procedure for HCC than DSA alone.
