Colorectal cancer (CRC) remains a leading cancer killer worldwide. But the disease is both curable and preventable at an early stage. Regular CRC cancer screening has been shown to reduce the risk of dying from CRC. H...Colorectal cancer (CRC) remains a leading cancer killer worldwide. But the disease is both curable and preventable at an early stage. Regular CRC cancer screening has been shown to reduce the risk of dying from CRC. However, the importance of large-scale screening is only now starting to be appreciated. This article reviews a variety of imaging procedures available for detecting ulcerative colitis (UC) and Crohn's disease (CD), polyps and CRC in their early stage and also presents details on various screening options. Detecting, staging and re-staging of patients with CRC also require multimodality, multistep imaging approaches. Staging and re-staging with conventional colonoscopy (CC), computer tomography colonography (CTC), magnetic resonance colonography (MRC) and positron emission tomography/computer tomography colonography (PET/CTC) are of paramount importance in determining the most appropriate therapeutic method and in predicting the risk of tumor recurrence and overall prognosis. The advantages and limitations of these modalities are also discussed.展开更多
AIM:To validate high definition endoscopes with Fujinon intelligent chromoendoscopy(FICE) in colonoscopy.METHODS:The image quality of normal white light endoscopy(WLE),that of the 10 available FICE filters and that of...AIM:To validate high definition endoscopes with Fujinon intelligent chromoendoscopy(FICE) in colonoscopy.METHODS:The image quality of normal white light endoscopy(WLE),that of the 10 available FICE filters and that of a gold standard(0.2% indigo carmine dye) were compared.RESULTS:FICE-filter 4 [red,green,and blue(RGB) wavelengths of 520,500,and 405 nm,respectively] provided the best images for evaluating the vascular pattern compared to white light.The mucosal surface was best assessed using filter 4.However,the views obtained were not rated significantly better than those observed with white light.The "gold standard",indigo carmine(IC) dye,was found to be superior to both white light and filter 4.Filter 6(RGB wavelengths of 580,520,and 460 nm,respectively) allowed for exploration of the IC-stained mucosa.When assessing mucosal polyps,both FICE with magnification,and magnification following dye spraying were superior to the same techniques without magnification and to white light imaging.In the presence of suboptimal bowel preparation,observation with the FICE mode was possible,and endoscopists considered it to be superior to observation with white light.CONCLUSION:FICE-filter 4 with magnification improves the image quality of the colonic vascular patterns obtained with WLE.展开更多
目的:评估低剂量CT仿真结肠镜结合增强扫描对结直肠疾病的诊断价值。方法:对104例受检者进行低剂量CT仿真结肠镜及增强扫描检查,将检查结果与结肠镜活检病理结果进行比较,计算低剂量CT仿真结肠镜诊断病变的敏感度和特异度,并分别记录低...目的:评估低剂量CT仿真结肠镜结合增强扫描对结直肠疾病的诊断价值。方法:对104例受检者进行低剂量CT仿真结肠镜及增强扫描检查,将检查结果与结肠镜活检病理结果进行比较,计算低剂量CT仿真结肠镜诊断病变的敏感度和特异度,并分别记录低剂量和常规剂量扫描的CT容积剂量指数(CT dose index volume,CTDI vol)。结果:104例受检者中,阳性病变者91例,阴性13例。其中低剂量CT仿真结肠镜检出阳性者89例(89/91,97.8%),低剂量CT的CT辐射指数较常规CT平均降低60.59%。与常规剂量CT相比,低剂量CT仿真结肠镜对肠壁浸润程度、病变定性及腹膜后淋巴结的显示均稍差,而增强扫描有助于弥补这些不足。结论:低剂量CT仿真结肠镜检查可以有效地发现结直肠病变,且较常规CT的X线辐射剂量低;增强扫描适用于结直肠癌术前分期,低剂量CT仿真结肠镜结合增强扫描对结直肠疾病的诊断有较高价值。展开更多
Recent advancements in virtual reality graphics and models have allowed virtual reality simulators to be incorporated into a variety of endoscopic training programmes. Use of virtual reality simulators in training pro...Recent advancements in virtual reality graphics and models have allowed virtual reality simulators to be incorporated into a variety of endoscopic training programmes. Use of virtual reality simulators in training programmes is thought to improve skill acquisition amongst trainees which is reflected in improved patient comfort and safety. Several studies have already been carried out to ascertain the impact that usage of virtual reality simulators may have upon trainee learning curves and how this may translate to patient comfort. This article reviews the available literature in this area of medical education which is particularly relevant to all parties involved in endoscopy training and curriculum development. Assessment of the available evidence for an optimal exposure time with virtual reality simula-tors and the long-term benefits of their use are also discussed.展开更多
Adequate screening methods can decrease colorectal cancer(CRC) mortality.The guaiac test for fecal occultblood(FOBT) is part of the German CRC Screening Program since 1970 and has evidence level Ia.In randomized multi...Adequate screening methods can decrease colorectal cancer(CRC) mortality.The guaiac test for fecal occultblood(FOBT) is part of the German CRC Screening Program since 1970 and has evidence level Ia.In randomized multicenter-studies FOBT has an average sensitivity of 24% and decreases CRC mortality up to 30%.Immunological tests for human haemoglobin(iFOBT) show better performance characteristics than guaiac FOBT,with augmented sensitivity and specificity.However,the single tests show wide differences in diagnostic performance and iFOBT is not yet covered by insurance companies although it should replace the guaiac test for CRC screening.Visual colonoscopy,which was introduced to the German National Cancer Screening Program in 2002,is the gold standard for the diagnosis of colorectal neoplasia.From 2003 to 2007 more than 2.8 million examinations have been documented in Germany.The prevalence of adenomas is around 20% and of CRC about 0.7% to 1.0% of the screenings.Seventy percent of the carcinomas detected during screening are in an early stage(UICCⅠand Ⅱ).Furthermore,screening colonoscopy is a cost saving procedure with a low complication rate(0.25% overall).Insurance companies save 216€ for each screening colonoscopy mainly by prevention of neoplasia due to polypectomy.In Germany,virtual colonography by computed tomography(CT) or magnetic resonance imaging still lacks standardization of the hard and software.In experienced centres the sensitivity for CRC and large polyps of CT colonography is comparable to colonoscopy but in meta-analyses the ranking is lower.New technologies like computer-aided colonoscopies with sheath or double balloon techniques are coming up as well as capsule colonoscopy,which sensitivity for large polyps is about 70%.Advised by his physician,the patient can choose his most acceptable examination method from this whole set of screening tools.展开更多
Twenty years after its introduction, computed tomographic colonography (CTC) has reached its maturity, and it can reasonably be considered the best radiological diagnostic test for imaging colorectal cancer (CRC) and ...Twenty years after its introduction, computed tomographic colonography (CTC) has reached its maturity, and it can reasonably be considered the best radiological diagnostic test for imaging colorectal cancer (CRC) and polyps. This examination technique is less invasive than colonoscopy (CS), easy to perform, and standardized. Reduced bowel preparation and colonic distention using carbon dioxide favor patient compliance. Widespread implementation of a new image reconstruction algorithm has minimized radiation exposure, and the use of dedicated software with enhanced views has enabled easier image interpretation. Integration in the routine workflow of a computer-aided detection algorithm reduces perceptual errors, particularly for small polyps. Consolidated evidence from the literature shows that the diagnostic performances for the detection of CRC and large polyps in symptomatic and asymptomatic individuals are similar to CS and are largely superior to barium enema, the latter of which should be strongly discouraged. Favorable data regarding CTC performance open the possibility for many different indications, some of which are already supported by evidence-based data: incomplete, failed, or unfeasible CS; symptomatic, elderly, and frail patients; and investigation of diverticular disease. Other indications are still being debated and, thus, are recommended only if CS is unfeasible: the use of CTC in CRC screening and in surveillance after surgery for CRC or polypectomy. In order for CTC to be used appropriately, contraindications such as acute abdominal conditions (diverticulitis or the acute phase of inflammatory bowel diseases) and surveillance in patients with a long-standing history of ulcerative colitis or Crohn’s disease and in those with hereditary colonic syndromes should not be overlooked. This will maximize the benefits of the technique and minimize potential sources of frustration or disappointment for both referring clinicians and patients.展开更多
AIM:To investigate the perceived impact of computed tomographic colonography(CTC) on endoscopists' current and future practice.METHODS:A 21-question survey was mailed to 1570 randomly chosen American Society for G...AIM:To investigate the perceived impact of computed tomographic colonography(CTC) on endoscopists' current and future practice.METHODS:A 21-question survey was mailed to 1570 randomly chosen American Society for Gastrointestinal Endoscopy(ASGE) members.Participants reported socio-demographics,colonoscopy volume,percentage of colonoscopies performed for screening,and likelihood of integration of CTC into their practice.RESULTS:A total of 367 ASGE members(23%) returned the questionnaire.Respondents were predominantly male(> 90%) and white(83%) with an average age of 49 years.Most respondents(58%) had no plans to incorporate CTC into daily practice and only 7% had already incorporated CTC into daily practice.Private practice respondents were the least likely to incorporate this modality into their daily practice(P=0.047).Forty-three percent of participants were willing to take courses on CTC reading,particularly those with the highest volume of colonoscopy(P=0.049).Forty percent of participants were unsure of CTC's impact on future colonoscopy volume while 21% and 18% projected a decreased and increased volume,respectively.The estimated impact of CTC volume varied significantly by age(P=0.002).Respondents > 60 years felt that CTC would increase colonoscopy,whereas those < 40 years thought CTC would ultimately decrease colonoscopy.CONCLUSION:Practicing endoscopists are not enthusiastic about the incorporation of CTC into their daily practice and are unsure of its future impact on their practice.展开更多
AIM： To report our experience with computed tomography colonography （CTC） systematically performed in subjects with positive faecal occult blood test （FOBT） and an incomplete colonoscopy in the setting of a popul...AIM： To report our experience with computed tomography colonography （CTC） systematically performed in subjects with positive faecal occult blood test （FOBT） and an incomplete colonoscopy in the setting of a population-based screening for colorectal cancer （CRC）. METHODS： From April 2006 to April 2007, 43 290 individuals （age range 50-70） who adhered to the regional screening program for the prevention of CRC underwent immunochemical FOBT. FOBT was positive in 1882 subjects （4.3%）. 1463 （77.7%） of these subjects underwent colonoscopy, 903 performed in a single center. Of 903 colonoscopies 65 （7.2%） were incomplete. Forty-two of these subjects underwent CTC. CTC was performed with a 16-MDCT scanner after standard bowel prep （polyethyleneglycole） in both supine and prone position. Subjects whose CTC showed polyps or masses were referred to the endoscopist for repeat colonoscopy under sedation or underwent surgery. Perlesion and per-segment positive predictive values （PPV） were calculated. RESULTS： Twenty-one （50%） of 42 CTCs showed polyps or masses. Fifty-five of these subjects underwent a repeat colonoscopy, whereas 2 subjects underwent surgery for colonic masses of indeterminate nature. Four subjects refused further examinations. CTC correctly identified 2 colonic masses and 20 polyps. PPV for masses or polyps greater than 9 mm was of 87.5%. Per-lesion and per-segment PPV were, respectively, 83.3% and 83.3% for polyps greater or equal to 10 mm, and 77.8% and 85.7% for polyps of 6-9 mm. CONCLUSION： In the context of a screening program for CRC based on FOBT, CTC shows high per-segment and per-lesion PPV for colonic masses and polyps greater than 9 mm. Therefore, CTC has the potential to become a useful technique for evaluation of the non visualized part of the colon after incomplete colonoscopy.展开更多
Although colorectal cancer (CRC) has no longer been the leading cancer killer worldwide for years with the exponential development in computed tomography (CT) or magnetic resonance imaging, and positron emission tomog...Although colorectal cancer (CRC) has no longer been the leading cancer killer worldwide for years with the exponential development in computed tomography (CT) or magnetic resonance imaging, and positron emission tomography/CT as well as virtual colonoscopy for early detection, the CRC related mortality is still high. The objective of CRC screening is to reduce the burden of CRC and thereby the morbidity and mortality rates of the disease. It is believed that this goal can be achieved by regularly screening the average-risk population, enabling the detection of cancer at early, curable stages, and polyps before they become cancerous. Large-scale screening with multimodality imaging approaches plays an important role in reaching that goal to detect polyps, Crohn's disease, ulcerative colitis and CRC in early stage. This article reviews kinds of presentative imaging procedures for various screening options and updates detecting, staging and re-staging of CRC patients for determining the optimal therapeutic method and forecasting the risk of CRC recurrence and the overall prognosis. The combination use of virtual colonoscopy and conventional endoscopy, advantages and limitations of these modalities are also discussed. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.展开更多
Colorectal cancer(CRC) represents one of the most relevant causes of morbidity and mortality in Western societies. CRC screening is actually based on faecal occult blood testing, and optical colonoscopy still remains ...Colorectal cancer(CRC) represents one of the most relevant causes of morbidity and mortality in Western societies. CRC screening is actually based on faecal occult blood testing, and optical colonoscopy still remains the gold standard screening test for cancer detection. However, computed tomography colonography(CT colonography) constitutes a reliable, minimally-invasive method to rapidly and effectively evaluate the entire colon for clinically relevant lesions. Furthermore, even if the benefits of its employment in CRC mass screening have not fully established yet, CT colonography may represent a reasonable alternative screening test in patients who cannot undergo or refuse colonoscopy. Therefore, the purpose of our review is to illustrate the most updated recommendations on methodology and the current clinical indications of CT colonography, according to the data of the existing relevant literature.展开更多
The diagnostic value of virtual colonoscopy versus colonoscopy was compared in detection of colorectal neoplasia. Virtual colonoscopy was performed on 29 patients with suspected colorectal diseases, Results were compa...The diagnostic value of virtual colonoscopy versus colonoscopy was compared in detection of colorectal neoplasia. Virtual colonoscopy was performed on 29 patients with suspected colorectal diseases, Results were compared with colonoscopy for each case. Virtual colonoscopy was successfully performed on each patient. All patients tolerated virtual colonoscopy well, had no complications. All colorectal malignance were identified both by virtual colonoscopy and colonoscopy. Twenty-five polyps were detected with colonoscopy, whereas only 16 polyps were defined by virtual colonoscopy. Detection rates of polyps greater than 1.0 cm,between 0.5-0.9 cm and less than 0.5 cm in size were 90%,62.5% and 28.6% respectively. Virtual colonoscopy is fast, minimally invasive and well tolerated. This technique is a valuable clinical method in diagnosis of colorectal malignance and polyps larger than 0.5 cm in size.展开更多
文摘Colorectal cancer (CRC) remains a leading cancer killer worldwide. But the disease is both curable and preventable at an early stage. Regular CRC cancer screening has been shown to reduce the risk of dying from CRC. However, the importance of large-scale screening is only now starting to be appreciated. This article reviews a variety of imaging procedures available for detecting ulcerative colitis (UC) and Crohn's disease (CD), polyps and CRC in their early stage and also presents details on various screening options. Detecting, staging and re-staging of patients with CRC also require multimodality, multistep imaging approaches. Staging and re-staging with conventional colonoscopy (CC), computer tomography colonography (CTC), magnetic resonance colonography (MRC) and positron emission tomography/computer tomography colonography (PET/CTC) are of paramount importance in determining the most appropriate therapeutic method and in predicting the risk of tumor recurrence and overall prognosis. The advantages and limitations of these modalities are also discussed.
基金Supported by Consejería de Educación,Cultura y Deportes,Gobierno de Canarias PI2002/138,the Instituto de Salud Carlos III C03/02
文摘AIM:To validate high definition endoscopes with Fujinon intelligent chromoendoscopy(FICE) in colonoscopy.METHODS:The image quality of normal white light endoscopy(WLE),that of the 10 available FICE filters and that of a gold standard(0.2% indigo carmine dye) were compared.RESULTS:FICE-filter 4 [red,green,and blue(RGB) wavelengths of 520,500,and 405 nm,respectively] provided the best images for evaluating the vascular pattern compared to white light.The mucosal surface was best assessed using filter 4.However,the views obtained were not rated significantly better than those observed with white light.The "gold standard",indigo carmine(IC) dye,was found to be superior to both white light and filter 4.Filter 6(RGB wavelengths of 580,520,and 460 nm,respectively) allowed for exploration of the IC-stained mucosa.When assessing mucosal polyps,both FICE with magnification,and magnification following dye spraying were superior to the same techniques without magnification and to white light imaging.In the presence of suboptimal bowel preparation,observation with the FICE mode was possible,and endoscopists considered it to be superior to observation with white light.CONCLUSION:FICE-filter 4 with magnification improves the image quality of the colonic vascular patterns obtained with WLE.
文摘目的:评估低剂量CT仿真结肠镜结合增强扫描对结直肠疾病的诊断价值。方法:对104例受检者进行低剂量CT仿真结肠镜及增强扫描检查,将检查结果与结肠镜活检病理结果进行比较,计算低剂量CT仿真结肠镜诊断病变的敏感度和特异度,并分别记录低剂量和常规剂量扫描的CT容积剂量指数(CT dose index volume,CTDI vol)。结果:104例受检者中,阳性病变者91例,阴性13例。其中低剂量CT仿真结肠镜检出阳性者89例(89/91,97.8%),低剂量CT的CT辐射指数较常规CT平均降低60.59%。与常规剂量CT相比,低剂量CT仿真结肠镜对肠壁浸润程度、病变定性及腹膜后淋巴结的显示均稍差,而增强扫描有助于弥补这些不足。结论:低剂量CT仿真结肠镜检查可以有效地发现结直肠病变,且较常规CT的X线辐射剂量低;增强扫描适用于结直肠癌术前分期,低剂量CT仿真结肠镜结合增强扫描对结直肠疾病的诊断有较高价值。
文摘Recent advancements in virtual reality graphics and models have allowed virtual reality simulators to be incorporated into a variety of endoscopic training programmes. Use of virtual reality simulators in training programmes is thought to improve skill acquisition amongst trainees which is reflected in improved patient comfort and safety. Several studies have already been carried out to ascertain the impact that usage of virtual reality simulators may have upon trainee learning curves and how this may translate to patient comfort. This article reviews the available literature in this area of medical education which is particularly relevant to all parties involved in endoscopy training and curriculum development. Assessment of the available evidence for an optimal exposure time with virtual reality simula-tors and the long-term benefits of their use are also discussed.
文摘Adequate screening methods can decrease colorectal cancer(CRC) mortality.The guaiac test for fecal occultblood(FOBT) is part of the German CRC Screening Program since 1970 and has evidence level Ia.In randomized multicenter-studies FOBT has an average sensitivity of 24% and decreases CRC mortality up to 30%.Immunological tests for human haemoglobin(iFOBT) show better performance characteristics than guaiac FOBT,with augmented sensitivity and specificity.However,the single tests show wide differences in diagnostic performance and iFOBT is not yet covered by insurance companies although it should replace the guaiac test for CRC screening.Visual colonoscopy,which was introduced to the German National Cancer Screening Program in 2002,is the gold standard for the diagnosis of colorectal neoplasia.From 2003 to 2007 more than 2.8 million examinations have been documented in Germany.The prevalence of adenomas is around 20% and of CRC about 0.7% to 1.0% of the screenings.Seventy percent of the carcinomas detected during screening are in an early stage(UICCⅠand Ⅱ).Furthermore,screening colonoscopy is a cost saving procedure with a low complication rate(0.25% overall).Insurance companies save 216€ for each screening colonoscopy mainly by prevention of neoplasia due to polypectomy.In Germany,virtual colonography by computed tomography(CT) or magnetic resonance imaging still lacks standardization of the hard and software.In experienced centres the sensitivity for CRC and large polyps of CT colonography is comparable to colonoscopy but in meta-analyses the ranking is lower.New technologies like computer-aided colonoscopies with sheath or double balloon techniques are coming up as well as capsule colonoscopy,which sensitivity for large polyps is about 70%.Advised by his physician,the patient can choose his most acceptable examination method from this whole set of screening tools.
文摘Twenty years after its introduction, computed tomographic colonography (CTC) has reached its maturity, and it can reasonably be considered the best radiological diagnostic test for imaging colorectal cancer (CRC) and polyps. This examination technique is less invasive than colonoscopy (CS), easy to perform, and standardized. Reduced bowel preparation and colonic distention using carbon dioxide favor patient compliance. Widespread implementation of a new image reconstruction algorithm has minimized radiation exposure, and the use of dedicated software with enhanced views has enabled easier image interpretation. Integration in the routine workflow of a computer-aided detection algorithm reduces perceptual errors, particularly for small polyps. Consolidated evidence from the literature shows that the diagnostic performances for the detection of CRC and large polyps in symptomatic and asymptomatic individuals are similar to CS and are largely superior to barium enema, the latter of which should be strongly discouraged. Favorable data regarding CTC performance open the possibility for many different indications, some of which are already supported by evidence-based data: incomplete, failed, or unfeasible CS; symptomatic, elderly, and frail patients; and investigation of diverticular disease. Other indications are still being debated and, thus, are recommended only if CS is unfeasible: the use of CTC in CRC screening and in surveillance after surgery for CRC or polypectomy. In order for CTC to be used appropriately, contraindications such as acute abdominal conditions (diverticulitis or the acute phase of inflammatory bowel diseases) and surveillance in patients with a long-standing history of ulcerative colitis or Crohn’s disease and in those with hereditary colonic syndromes should not be overlooked. This will maximize the benefits of the technique and minimize potential sources of frustration or disappointment for both referring clinicians and patients.
文摘AIM:To investigate the perceived impact of computed tomographic colonography(CTC) on endoscopists' current and future practice.METHODS:A 21-question survey was mailed to 1570 randomly chosen American Society for Gastrointestinal Endoscopy(ASGE) members.Participants reported socio-demographics,colonoscopy volume,percentage of colonoscopies performed for screening,and likelihood of integration of CTC into their practice.RESULTS:A total of 367 ASGE members(23%) returned the questionnaire.Respondents were predominantly male(> 90%) and white(83%) with an average age of 49 years.Most respondents(58%) had no plans to incorporate CTC into daily practice and only 7% had already incorporated CTC into daily practice.Private practice respondents were the least likely to incorporate this modality into their daily practice(P=0.047).Forty-three percent of participants were willing to take courses on CTC reading,particularly those with the highest volume of colonoscopy(P=0.049).Forty percent of participants were unsure of CTC's impact on future colonoscopy volume while 21% and 18% projected a decreased and increased volume,respectively.The estimated impact of CTC volume varied significantly by age(P=0.002).Respondents > 60 years felt that CTC would increase colonoscopy,whereas those < 40 years thought CTC would ultimately decrease colonoscopy.CONCLUSION:Practicing endoscopists are not enthusiastic about the incorporation of CTC into their daily practice and are unsure of its future impact on their practice.
文摘AIM： To report our experience with computed tomography colonography （CTC） systematically performed in subjects with positive faecal occult blood test （FOBT） and an incomplete colonoscopy in the setting of a population-based screening for colorectal cancer （CRC）. METHODS： From April 2006 to April 2007, 43 290 individuals （age range 50-70） who adhered to the regional screening program for the prevention of CRC underwent immunochemical FOBT. FOBT was positive in 1882 subjects （4.3%）. 1463 （77.7%） of these subjects underwent colonoscopy, 903 performed in a single center. Of 903 colonoscopies 65 （7.2%） were incomplete. Forty-two of these subjects underwent CTC. CTC was performed with a 16-MDCT scanner after standard bowel prep （polyethyleneglycole） in both supine and prone position. Subjects whose CTC showed polyps or masses were referred to the endoscopist for repeat colonoscopy under sedation or underwent surgery. Perlesion and per-segment positive predictive values （PPV） were calculated. RESULTS： Twenty-one （50%） of 42 CTCs showed polyps or masses. Fifty-five of these subjects underwent a repeat colonoscopy, whereas 2 subjects underwent surgery for colonic masses of indeterminate nature. Four subjects refused further examinations. CTC correctly identified 2 colonic masses and 20 polyps. PPV for masses or polyps greater than 9 mm was of 87.5%. Per-lesion and per-segment PPV were, respectively, 83.3% and 83.3% for polyps greater or equal to 10 mm, and 77.8% and 85.7% for polyps of 6-9 mm. CONCLUSION： In the context of a screening program for CRC based on FOBT, CTC shows high per-segment and per-lesion PPV for colonic masses and polyps greater than 9 mm. Therefore, CTC has the potential to become a useful technique for evaluation of the non visualized part of the colon after incomplete colonoscopy.
文摘Although colorectal cancer (CRC) has no longer been the leading cancer killer worldwide for years with the exponential development in computed tomography (CT) or magnetic resonance imaging, and positron emission tomography/CT as well as virtual colonoscopy for early detection, the CRC related mortality is still high. The objective of CRC screening is to reduce the burden of CRC and thereby the morbidity and mortality rates of the disease. It is believed that this goal can be achieved by regularly screening the average-risk population, enabling the detection of cancer at early, curable stages, and polyps before they become cancerous. Large-scale screening with multimodality imaging approaches plays an important role in reaching that goal to detect polyps, Crohn's disease, ulcerative colitis and CRC in early stage. This article reviews kinds of presentative imaging procedures for various screening options and updates detecting, staging and re-staging of CRC patients for determining the optimal therapeutic method and forecasting the risk of CRC recurrence and the overall prognosis. The combination use of virtual colonoscopy and conventional endoscopy, advantages and limitations of these modalities are also discussed. (C) 2014 Baishideng Publishing Group Inc. All rights reserved.
文摘Colorectal cancer(CRC) represents one of the most relevant causes of morbidity and mortality in Western societies. CRC screening is actually based on faecal occult blood testing, and optical colonoscopy still remains the gold standard screening test for cancer detection. However, computed tomography colonography(CT colonography) constitutes a reliable, minimally-invasive method to rapidly and effectively evaluate the entire colon for clinically relevant lesions. Furthermore, even if the benefits of its employment in CRC mass screening have not fully established yet, CT colonography may represent a reasonable alternative screening test in patients who cannot undergo or refuse colonoscopy. Therefore, the purpose of our review is to illustrate the most updated recommendations on methodology and the current clinical indications of CT colonography, according to the data of the existing relevant literature.
文摘The diagnostic value of virtual colonoscopy versus colonoscopy was compared in detection of colorectal neoplasia. Virtual colonoscopy was performed on 29 patients with suspected colorectal diseases, Results were compared with colonoscopy for each case. Virtual colonoscopy was successfully performed on each patient. All patients tolerated virtual colonoscopy well, had no complications. All colorectal malignance were identified both by virtual colonoscopy and colonoscopy. Twenty-five polyps were detected with colonoscopy, whereas only 16 polyps were defined by virtual colonoscopy. Detection rates of polyps greater than 1.0 cm,between 0.5-0.9 cm and less than 0.5 cm in size were 90%,62.5% and 28.6% respectively. Virtual colonoscopy is fast, minimally invasive and well tolerated. This technique is a valuable clinical method in diagnosis of colorectal malignance and polyps larger than 0.5 cm in size.
