BACKGROUND In hepatocellular carcinoma(HCC),detection and treatment prior to growth beyond 2 cm are important as a larger tumor size is more frequently associated with microvascular invasion and/or satellites.In the s...BACKGROUND In hepatocellular carcinoma(HCC),detection and treatment prior to growth beyond 2 cm are important as a larger tumor size is more frequently associated with microvascular invasion and/or satellites.In the surveillance of very small HCC nodules(≤2 cm in maximum diameter,Barcelona clinical stage 0),we demonstrated that the tumor markers alpha-fetoprotein and PIVKA-Ⅱare not so useful.Therefore,we must survey with imaging modalities.The superiority of magnetic resonance imaging(MRI)over ultrasound(US)to detect HCC was confirmed in many studies.Although enhanced MRI is now performed to accurately diagnose HCC,in conventional clinical practice for HCC surveillance in liver diseases,unenhanced MRI is widely performed throughout the world.While,MRI has made marked improvements in recent years.AIM To make a comparison of unenhanced MRI and US in detecting very small HCC that was examined in the last ten years in patients in whom MRI and US examinations were performed nearly simultaneously.METHODS In 394 patients with very small HCC nodules,those who underwent MRI and US at nearly the same time(on the same day whenever possible or at least within 14 days of one another)at the first diagnosis of HCC were selected.The detection rate of HCC with unenhanced MRI was investigated and compared with that of unenhanced US.RESULTS The sensitivity of unenhanced MRI for detecting very small HCC was 95.1%(97/102,95%confidence interval:90.9-99.3)and that of unenhanced US was 69.6%(71/102,95%confidence interval:60.7-78.5).The sensitivity of unenhanced MRI for detecting very small HCC was significantly higher than that of unenhanced US(P<0.001).Regarding the location of HCC in the liver in patients in whom detection by US was unsuccessful,S7-8 was identified in 51.7%.CONCLUSION Currently,unenhanced MRI is a very useful tool for the surveillance of very small HCC in conventional clinical follow-up practice.展开更多
This article presents a brief overview of the development of high-resolution SPECT for small-animal im- aging. A pinhole collimator has been used for high-resolution animal SPECT to provide better spatial resolution a...This article presents a brief overview of the development of high-resolution SPECT for small-animal im- aging. A pinhole collimator has been used for high-resolution animal SPECT to provide better spatial resolution and detection efficiency in comparison with a parallel-hole collimator. The theory of imaging characteristics of the pin- hole collimator is presented and the designs of the pinhole aperture are discussed. The detector technologies used for the development of small-animal SPECT and the recent advances are presented. The evolving trend of small-animal SPECT is toward a multi-pinhole and a multi-detector system to obtain a high resolution and also a high detection ef- ficiency.展开更多
Objective： We examined 103 cases over the last five years and discussed diagnosis and treatment of alpha- fetoprotein （AFP）-negative small hepatic lesions. Background： Small hepatic lesions （less than 2 cm in dia...Objective： We examined 103 cases over the last five years and discussed diagnosis and treatment of alpha- fetoprotein （AFP）-negative small hepatic lesions. Background： Small hepatic lesions （less than 2 cm in diameter） usually have no typical imaging characteristics and therefore are difficult to diagnose, especially when AFP tests provide a negative result. Methods： A total of 103 patients with AFP-negative small hepatic lesions from January 2003 to December 2008 were retrospectively reviewed. Differential diagnosis was performed by digital subtraction angiography （DSA）, dynamic contrast-enhanced magnetic resonance imaging （DCE-MRI）, contrast-enhanced ultrasound （CEUS）, or positron emission tomography-computed tomography （PET-CT） based on the multiplicity of lesions. Ninety-four patients with suspected cancers underwent partial hepatectomy. Clinical data were collected from hospital records and follow-up questionnaires. Results： Hepatocellular carcinoma （HCC） diagnostic sensitivity of DSA, DCE-MRI, CEUS and PET-CT was 88.2%, 93.9%, 88.9% and 88.9%, respectively. The surgery-related complication rate was 6.4%. Prognosis was good, with 1- and 3-year survival rates of 98.8% and 76.1%, respectively. Conclusions： DSA, DCE-MRI, CEUS and PET-CT are valuable for diagnosis of small hepatic lesions. Partial hepatectomy is a preferred surgical procedure. Surgery for small liver cancers usually has little risk and good prognosis, therefore it can be actively applied in suspected HCC cases.展开更多
AIM:To evaluate the potential use of colonoscopy and endoluminal ultrasonic biomicroscopy(eUBM)to track the progression of mouse colonic lesions.METHODS:Ten mice were treated with a single azoxy-methane intraperitonea...AIM:To evaluate the potential use of colonoscopy and endoluminal ultrasonic biomicroscopy(eUBM)to track the progression of mouse colonic lesions.METHODS:Ten mice were treated with a single azoxy-methane intraperitoneal injection(week 1)followed by seven days of a dextran sulfate sodium treatment in their drinking water(week 2)to induce inflammationassociated colon tumors.eUBM was performed simultaneously with colonoscopy at weeks 13,17-20 and21.A 3.6-F diameter 40 MHz mini-probe catheter was used for eUBM imaging.The ultrasound mini-probe catheter was inserted into the accessory channel of a pediatric flexible bronchofiberscope,allowing simultaneous acquisition of colonoscopic and eUBM images.During image acquisition,the mice were anesthetized with isoflurane and kept in a supine position over a stainless steel heated surgical waterbed at 37℃.Both eUBM and colonoscopic images were captured and stored when a lesion was detected by colonoscopy or when the eUBM image revealed a modified colon wall anatomy.During the procedure,the colon was irrigated with water that was injected through a flush port on the mini-probe catheter and that acted as the ultrasound coupling medium between the transducer and the colon wall.Once the acquisition of the last eUBM/colonoscopy section for each animal was completed,the colons were fixed,paraffin-embedded,and stained with hematoxylin and eosin.Colon images acquired at the first time-point for each mouse were compared with subsequent eUBM/colonoscopic images of the same sites obtained in the following acquisitions to evaluate lesion progression.RESULTS:All 10 mice had eUBM and colonoscopic images acquired at week 13(the first time-point).Two animals died immediately after the first imaging acquisition and,consequently,only 8 mice were subjected to the second eUBM/colonoscopy imaging acquisition(at the second time-point).Due to the advanced stage of colonic tumorigenesis,5 animals died after the second time-point image acquisition,and thus,only three were subjected to the third eUBM/colonoscopy imaging acquisition(the third time-point).eUBM was able to detect the four layers in healthy segments of colon:the mucosa(the first hyperechoic layer moving away from the mini-probe axis),followed by the muscularis mucosae(hypoechoic),the submucosa(the second hyperechoic layer)and the muscularis externa(the second hypoechoic layer).Hypoechoic regions between the mucosa and the muscularis externa layers represented lymphoid infiltrates,as confirmed by the corresponding histological images.Pedunculated tumors were represented by hyperechoic masses in the mucosa layer.Among the lesions that decreased in size between the first and third time-points,one of the lesions changed from a mucosal hyperplasia with ulceration at the top to a mucosal hyperplasia with lymphoid infiltrate and,finally,to small signs of mucosal hyperplasia and lymphoid infiltrate.In this case,while lesion regression and modification were observable in the eUBM images,colonoscopy was only able to detect the lesion at the first and second time-points,without the capacity to demonstrate the presence of lymphoid infiltrate.Regarding the lesions that increased in size,one of them started as a small elevation in the mucosa layer and progressed to a pedunculated tumor.In this case,while eUBM imaging revealed the lesion at the first time-point,colonoscopy was only able to detect it at the second time-point.All colonic lesions(tumors,lymphoid infiltrate and mucosal thickening)were identified by eUBM,while colonoscopy identified just76%of them.Colonoscopy identified all of the colonic tumors but failed to diagnose lymphoid infiltrates and increased mucosal thickness and failed to differentiate lymphoid infiltrates from small adenomas.During the observation period,most of the lesions(approximately67%)increased in size,approximately 14%remained unchanged,and 19%regressed.CONCLUSION:Combining eUBM with colonoscopy improves the diagnosis and the follow-up of mouse colonic lesions,adding transmural assessment of the bowel wall.展开更多
基金The study was reviewed and approved by the Ethics Committee of Yokohama Municipal Citizen's Hospital Institutional Review Board(Approval No.21-02-01).
文摘BACKGROUND In hepatocellular carcinoma(HCC),detection and treatment prior to growth beyond 2 cm are important as a larger tumor size is more frequently associated with microvascular invasion and/or satellites.In the surveillance of very small HCC nodules(≤2 cm in maximum diameter,Barcelona clinical stage 0),we demonstrated that the tumor markers alpha-fetoprotein and PIVKA-Ⅱare not so useful.Therefore,we must survey with imaging modalities.The superiority of magnetic resonance imaging(MRI)over ultrasound(US)to detect HCC was confirmed in many studies.Although enhanced MRI is now performed to accurately diagnose HCC,in conventional clinical practice for HCC surveillance in liver diseases,unenhanced MRI is widely performed throughout the world.While,MRI has made marked improvements in recent years.AIM To make a comparison of unenhanced MRI and US in detecting very small HCC that was examined in the last ten years in patients in whom MRI and US examinations were performed nearly simultaneously.METHODS In 394 patients with very small HCC nodules,those who underwent MRI and US at nearly the same time(on the same day whenever possible or at least within 14 days of one another)at the first diagnosis of HCC were selected.The detection rate of HCC with unenhanced MRI was investigated and compared with that of unenhanced US.RESULTS The sensitivity of unenhanced MRI for detecting very small HCC was 95.1%(97/102,95%confidence interval:90.9-99.3)and that of unenhanced US was 69.6%(71/102,95%confidence interval:60.7-78.5).The sensitivity of unenhanced MRI for detecting very small HCC was significantly higher than that of unenhanced US(P<0.001).Regarding the location of HCC in the liver in patients in whom detection by US was unsuccessful,S7-8 was identified in 51.7%.CONCLUSION Currently,unenhanced MRI is a very useful tool for the surveillance of very small HCC in conventional clinical follow-up practice.
文摘This article presents a brief overview of the development of high-resolution SPECT for small-animal im- aging. A pinhole collimator has been used for high-resolution animal SPECT to provide better spatial resolution and detection efficiency in comparison with a parallel-hole collimator. The theory of imaging characteristics of the pin- hole collimator is presented and the designs of the pinhole aperture are discussed. The detector technologies used for the development of small-animal SPECT and the recent advances are presented. The evolving trend of small-animal SPECT is toward a multi-pinhole and a multi-detector system to obtain a high resolution and also a high detection ef- ficiency.
基金supported by China Medical Board in New York (CMB,11-045)National Natural Science Foundation of China (30970623 and 81201566)+2 种基金International Science and Technology Cooperation Projects (2010DFA31840 and 2010DFB33720)Program for New Century Excellent Talents in University (NCET-11-0288)Beijing Natural Science Foundation (5112030)
文摘Objective： We examined 103 cases over the last five years and discussed diagnosis and treatment of alpha- fetoprotein （AFP）-negative small hepatic lesions. Background： Small hepatic lesions （less than 2 cm in diameter） usually have no typical imaging characteristics and therefore are difficult to diagnose, especially when AFP tests provide a negative result. Methods： A total of 103 patients with AFP-negative small hepatic lesions from January 2003 to December 2008 were retrospectively reviewed. Differential diagnosis was performed by digital subtraction angiography （DSA）, dynamic contrast-enhanced magnetic resonance imaging （DCE-MRI）, contrast-enhanced ultrasound （CEUS）, or positron emission tomography-computed tomography （PET-CT） based on the multiplicity of lesions. Ninety-four patients with suspected cancers underwent partial hepatectomy. Clinical data were collected from hospital records and follow-up questionnaires. Results： Hepatocellular carcinoma （HCC） diagnostic sensitivity of DSA, DCE-MRI, CEUS and PET-CT was 88.2%, 93.9%, 88.9% and 88.9%, respectively. The surgery-related complication rate was 6.4%. Prognosis was good, with 1- and 3-year survival rates of 98.8% and 76.1%, respectively. Conclusions： DSA, DCE-MRI, CEUS and PET-CT are valuable for diagnosis of small hepatic lesions. Partial hepatectomy is a preferred surgical procedure. Surgery for small liver cancers usually has little risk and good prognosis, therefore it can be actively applied in suspected HCC cases.
基金Supported by National Council for Scientific and Technological Development(CNPq)Brazilian Federal Agency for Support and Evaluation of Higher Education(CAPES) and Carlos Chagas Filho Foundation for Research Support of the State of Rio de Janeiro(FAPERJ)
文摘AIM:To evaluate the potential use of colonoscopy and endoluminal ultrasonic biomicroscopy(eUBM)to track the progression of mouse colonic lesions.METHODS:Ten mice were treated with a single azoxy-methane intraperitoneal injection(week 1)followed by seven days of a dextran sulfate sodium treatment in their drinking water(week 2)to induce inflammationassociated colon tumors.eUBM was performed simultaneously with colonoscopy at weeks 13,17-20 and21.A 3.6-F diameter 40 MHz mini-probe catheter was used for eUBM imaging.The ultrasound mini-probe catheter was inserted into the accessory channel of a pediatric flexible bronchofiberscope,allowing simultaneous acquisition of colonoscopic and eUBM images.During image acquisition,the mice were anesthetized with isoflurane and kept in a supine position over a stainless steel heated surgical waterbed at 37℃.Both eUBM and colonoscopic images were captured and stored when a lesion was detected by colonoscopy or when the eUBM image revealed a modified colon wall anatomy.During the procedure,the colon was irrigated with water that was injected through a flush port on the mini-probe catheter and that acted as the ultrasound coupling medium between the transducer and the colon wall.Once the acquisition of the last eUBM/colonoscopy section for each animal was completed,the colons were fixed,paraffin-embedded,and stained with hematoxylin and eosin.Colon images acquired at the first time-point for each mouse were compared with subsequent eUBM/colonoscopic images of the same sites obtained in the following acquisitions to evaluate lesion progression.RESULTS:All 10 mice had eUBM and colonoscopic images acquired at week 13(the first time-point).Two animals died immediately after the first imaging acquisition and,consequently,only 8 mice were subjected to the second eUBM/colonoscopy imaging acquisition(at the second time-point).Due to the advanced stage of colonic tumorigenesis,5 animals died after the second time-point image acquisition,and thus,only three were subjected to the third eUBM/colonoscopy imaging acquisition(the third time-point).eUBM was able to detect the four layers in healthy segments of colon:the mucosa(the first hyperechoic layer moving away from the mini-probe axis),followed by the muscularis mucosae(hypoechoic),the submucosa(the second hyperechoic layer)and the muscularis externa(the second hypoechoic layer).Hypoechoic regions between the mucosa and the muscularis externa layers represented lymphoid infiltrates,as confirmed by the corresponding histological images.Pedunculated tumors were represented by hyperechoic masses in the mucosa layer.Among the lesions that decreased in size between the first and third time-points,one of the lesions changed from a mucosal hyperplasia with ulceration at the top to a mucosal hyperplasia with lymphoid infiltrate and,finally,to small signs of mucosal hyperplasia and lymphoid infiltrate.In this case,while lesion regression and modification were observable in the eUBM images,colonoscopy was only able to detect the lesion at the first and second time-points,without the capacity to demonstrate the presence of lymphoid infiltrate.Regarding the lesions that increased in size,one of them started as a small elevation in the mucosa layer and progressed to a pedunculated tumor.In this case,while eUBM imaging revealed the lesion at the first time-point,colonoscopy was only able to detect it at the second time-point.All colonic lesions(tumors,lymphoid infiltrate and mucosal thickening)were identified by eUBM,while colonoscopy identified just76%of them.Colonoscopy identified all of the colonic tumors but failed to diagnose lymphoid infiltrates and increased mucosal thickness and failed to differentiate lymphoid infiltrates from small adenomas.During the observation period,most of the lesions(approximately67%)increased in size,approximately 14%remained unchanged,and 19%regressed.CONCLUSION:Combining eUBM with colonoscopy improves the diagnosis and the follow-up of mouse colonic lesions,adding transmural assessment of the bowel wall.
