CT colonography: can we achieve an adequate bowel preparation without diet restriction?

OBJECTIVE: To evaluate if an adequate bowel preparation for CT colonography, can be achieved without diet restriction, using a reduced amount of cathartic agent and fecal tagging. To investigate the influence of patients' characteristics on bowel preparation and the impact on patients' compliance. METHODS: In total, 1446 outpatients scheduled for elective CT colonography were prospectively enrolled. All patients had the same bowel preparation based on a reduced amount of cathartic agent (120 g of macrogol in 1.5 l of water) the day before the exam and a fecal tagging agent (60 ml of hyperosmolar oral iodinated agent) the day of the exam. No dietary restrictions were imposed before the exam. The bowel preparation was evaluated using a qualitative and quantitative score. Patients were grouped by age, gender, and presence of diverticula in both scores. Patients' compliance has been evaluated with a questionnaire after the end of the exam and with a phone-calling interview the day after the exam. RESULTS: According to the qualitative score, adequate bowel preparation was achieved in 1349 patients (93.29%) and no statistical differences were observed among the subgroups of patients. Quantitative scores demonstrated that colon distension was significantly better in younger patients and without diverticula. A good patients' compliance was observed and most patients (96.5%) were willing to repeat it. CONCLUSIONS: The lack of diet restriction does not affect the quality of CTC preparation and good patient's compliance could potentially increase the participation rate in CRC screening programs. KEY POINTS: • An adequate quality bowel preparation for CT colonography can be achieved without diet restriction, using a reduced amount of cathartic agent (120 g of macrogol in 1.5 l of water) and fecal tagging (60 ml of hyperosmolar oral iodinated agent). • A bowel preparation based on the combination of a reduced amount of cathartic agent and fecal tagging, without diet restriction, allows obtaining good quality in more than 90% of patients. • The bowel preparation scheme proposed reduces the distress and discomfort experienced by the patients improving adherence to CTC.

Comparison of the performance of conventional and spectral-based tagged stool cleansing algorithms at CT colonography.

OBJECTIVES: To compare the performance of conventional versus spectral-based electronic stool cleansing for iodine-tagged CT colonography (CTC) using a dual-layer spectral detector scanner. METHODS: We retrospectively evaluated iodine contrast stool-tagged CTC scans of 30 consecutive patients (mean age: 69 ± 8 years) undergoing colorectal cancer screening obtained on a dual-layer spectral detector CT scanner. One reader identified locations of electronic cleansing artifacts (n = 229) on conventional and spectral cleansed images. Three additional independent readers evaluated these locations using a conventional cleansing algorithm (Intellispace Portal) and two experimental spectral cleansing algorithms (i.e., fully transparent and translucent tagged stool). For each cleansed image set, readers recorded the severity of over- and under-cleansing artifacts on a 5-point Likert scale (0 = none to 4 = severe) and readability compared to uncleansed images. Wilcoxon's signed-rank tests were used to assess artifact severity, type, and readability (worse, unchanged, or better). RESULTS: Compared with conventional cleansing (66% score ≥ 2), the severity of overall cleansing artifacts was lower in transparent (60% score ≥ 2, p = 0.011) and translucent (50% score ≥ 2, p < 0.001) spectral cleansing. Under-cleansing artifact severity was lower in transparent (49% score ≥ 2, p < 0.001) and translucent (39% score ≥ 2, p < 0.001) spectral cleansing compared with conventional cleansing (60% score ≥ 2). Over-cleansing artifact severity was worse in transparent (17% score ≥ 2, p < 0.001) and translucent (14% score ≥ 2, p = 0.023) spectral cleansing compared with conventional cleansing (9% score ≥ 2). Overall readability was significantly improved in transparent (p < 0.001) and translucent (p < 0.001) spectral cleansing compared with conventional cleansing. CONCLUSIONS: Spectral cleansing provided more robust electronic stool cleansing of iodine-tagged stool at CTC than conventional cleansing. KEY POINTS: • Spectral-based electronic cleansing of tagged stool at CT colonography provides higher quality images with less perception of artifacts than does conventional cleansing. • Spectral-based electronic cleansing could potentially advance minimally cathartic approach for CT colonography. Further clinical trials are warranted.

Assessment of isocenter alignment during CT colonography: Implications for clinical practice.

INTRODUCTION: Optimization of image quality and patient radiation dose is achieved in part by positioning the patient at the isocenter of the CT gantry. The aim of this study was to establish whether there was increased isocenter misalignment (IM) in CT colonography (CTC) scans by comparing patient position during the prone part of a CTC to patient position during renal stone protocol CT (CT-KUB) and patient position during the supine part of a CTC to patient position during abdominopelvic CT (CT-AP). METHODS: Two hundred and twenty two consecutive outpatient adult CTC studies performed between January and December 2016 were retrospectively analyzed. Automated dose-tracking software was used to quantify IM in the x and y planes. Renal stone CT-KUB (n = 100) and standard CT-AP (n = 100) were used as comparison studies. RESULTS: IM during CTC was significantly greater in the y-axis compared with the x-axis for both prone (p = 0.002) and supine (p < 0.001) scanning. IM was significantly greater during prone CTC compared with CT-KUB (p = 0.008) and during supine CTC compared with CT-AP (p = 0.0001). IM was shown to be slightly greater in studies performed by more experienced radiographers (p = 0.04). IM was not associated with patient age, gender or size (p > 0.05 for all). CONCLUSION: Isocenter misalignment is greater during CT colonography compared with CT-KUB or CT-AP. Strategies for improving patient positioning could include radiographer education and automated patient centering solutions.

Sub-millisievert CT colonography: effect of knowledge-based iterative reconstruction on the detection of colonic polyps.

OBJECTIVES: To assess the feasibility of ultra-low dose computed tomography colonography (CTC) using knowledge-based iterative reconstruction (IR) and to determine its effect on polyp detection. METHODS: Forty-nine prospectively-enrolled patients underwent ultra-low dose CTC in the supine (100 kVp/20 mAs) and prone positions (80 kVp/20 mAs), followed by same-day colonoscopy. Thereafter, images were reconstructed using filtered back projection (FBP) and knowledge-based IR (IMR; Philips Healthcare, Best, Netherlands) algorithms. Effective radiation dose of CTC was recorded. Pooled per-polyp sensitivity and positive predictive value of three radiologists was analysed and compared between FBP and IMR. Image quality was assessed on a five-point scale and image noise was recorded using standard deviations. RESULTS: Mean effective radiation dose of ultra-low dose CTC was 0.90 ± 0.06 mSv. Eighty-nine polyps were detected on colonoscopy (mean, 8.5 ± 4.7 mm). The pooled per-polyp sensitivity for polyps 6.0-9.9 mm (n = 22) on CTC reconstructed with IMR (36/66, 54.5%) was not significantly different with that using FBP algorithm (34/66, 51.5%) (p = 0.414). For polyps ≥10 mm (n = 35), however, the pooled per-polyp sensitivity on CTC with IMR (73/105, 69.5%) was significantly higher than that with FBP (55/105, 52.4%) (p < 0.001). In particular, the difference of per-polyp sensitivity was statistically significant in intermediate (p = 0.014) and novice (p = 0.003) reviewers. Furthermore, mean image noise of IMR (8.4 ± 6.2 HU) was significantly lower than that of FBP (37.5 ± 13.9 HU) (p < 0.001) and image quality with IMR was significantly better than with FBP in all evaluated segments in all reviewers (all ps < 0.001). CONCLUSIONS: Sub-mSv CTC reconstructed with IMR was feasible for the detection of clinically significant polyps, demonstrating 70% per-polyp sensitivity of polyps ≥10 mm, while allowing significant noise reduction and improvement in image quality compared with FBP reconstruction. KEY POINTS: • Sub-mSv CTC using IMR demonstrated 70% per-polyp sensitivity for polyps ≥10 mm. • CTC using IMR significantly outperformed CTC reconstructed with FBP. • IMR allows significantly more noise reduction and improvement in image quality than FBP.

Double-Balloon Endoscopy after Incomplete Colonoscopy and Its Comparison with Computed Tomography Colonography.

BACKGROUND/AIMS: Because of the national screening program for colorectal carcinoma in The Netherlands, the number of colonoscopies has increased. In case of incomplete colonoscopy, computed tomography colonography (CTC) and double-balloon colonoscopy (DBc) are alternative options. This study evaluated cecal intubation rate and pathology detection rate in the previously unexplored part of the colon, complication rate of DBc, and CTC results after incomplete colonoscopy. METHODS: Retrospective observational study in a tertiary referral hospital regarding DBc and CTC reports from cases with incomplete colonoscopy. RESULTS: Sixty-three DBcs were performed after incomplete colonoscopy. Cecal intubation rate was 95%. Detection rate was 58% (5% carcinoma and 3% high-grade dysplastic adenoma). CTC preceded 54% of DBcs and 62% of CTC findings were confirmed. In 16%, a biopsy was taken, and in 60%, an intervention (mostly polypectomy) was performed. One major complication (1.5%) occurred, i.e., arterial bleeding due to polypectomy necessitating right hemicolectomy. CTC (n=213) showed a possible lesion in 35%, and could be confirmed by follow-up endoscopy or surgery in 65%. CONCLUSIONS: DBc is effective and safe for completion of colon inspection in incomplete colonoscopy. In patients with a high likelihood of pathology, DBc is preferred over CTC.

Double-Balloon Endoscopy after Incomplete Colonoscopy and Its Comparison with Computed Tomography Colonography

BACKGROUND/AIMS: Because of the national screening program for colorectal carcinoma in The Netherlands, the number of colonoscopies has increased. In case of incomplete colonoscopy, computed tomography colonography (CTC) and double-balloon colonoscopy (DBc) are alternative options. This study evaluated cecal intubation rate and pathology detection rate in the previously unexplored part of the colon, complication rate of DBc, and CTC results after incomplete colonoscopy. METHODS: Retrospective observational study in a tertiary referral hospital regarding DBc and CTC reports from cases with incomplete colonoscopy. RESULTS: Sixty-three DBcs were performed after incomplete colonoscopy. Cecal intubation rate was 95%. Detection rate was 58% (5% carcinoma and 3% high-grade dysplastic adenoma). CTC preceded 54% of DBcs and 62% of CTC findings were confirmed. In 16%, a biopsy was taken, and in 60%, an intervention (mostly polypectomy) was performed. One major complication (1.5%) occurred, i.e., arterial bleeding due to polypectomy necessitating right hemicolectomy. CTC (n=213) showed a possible lesion in 35%, and could be confirmed by follow-up endoscopy or surgery in 65%. CONCLUSIONS: DBc is effective and safe for completion of colon inspection in incomplete colonoscopy. In patients with a high likelihood of pathology, DBc is preferred over CTC.

Colon Capsule Endoscopy: Where Are We and Where Are We Going.

Colon capsule endoscopy (CCE) is a noninvasive technique for diagnostic imaging of the colon. It does not require air inflation or sedation and allows minimally invasive and painless colonic evaluation. The role of CCE is rapidly evolving; for example, for colorectal screening (colorectal cancer [CRC]) in average-risk patients, in patients with an incomplete colonoscopy, in patients refusing a conventional colonoscopy, and in patients with contraindications for conventional colonoscopy. In this paper, we comprehensively review the technical characteristics and procedure of CCE and compare CCE with conventional methods such as conventional colonoscopy or computed tomographic colonography. Future expansion of CCE in the area of CRC screening for the surveillance of polyps and adenomatous lesions and for assessment of inflammatory bowel disease is also discussed.

Burden of waiting for surveillance CT colonography in patients with screen-detected 6-9 mm polyps.

PURPOSE: We assessed the burden of waiting for surveillance CT colonography (CTC) performed in patients having 6-9 mm colorectal polyps on primary screening CTC. Additionally, we compared the burden of primary and surveillance CTC. MATERIALS AND METHODS: In an invitational population-based CTC screening trial, 101 persons were diagnosed with <3 polyps 6-9 mm, for which surveillance CTC after 3 years was advised. Validated questionnaires regarding expected and perceived burden (5-point Likert scales) were completed before and after index and surveillance CTC, also including items on burden of waiting for surveillance CTC. McNemar's test was used for comparison after dichotomization. RESULTS: Seventy-eight (77 %) of 101 invitees underwent surveillance CTC, of which 66 (85 %) completed the expected and 62 (79 %) the perceived burden questionnaire. The majority of participants (73 %) reported the experience of waiting for surveillance CTC as 'never' or 'only sometimes' burdensome. There was almost no difference in expected and perceived burden between surveillance and index CTC. Waiting for the results after the procedure was significantly more burdensome for surveillance CTC than for index CTC (23 vs. 8 %; p = 0.012). CONCLUSION: Waiting for surveillance CTC after primary CTC screening caused little or no burden for surveillance participants. In general, the burden of surveillance and index CTC were comparable. KEY POINTS: • Waiting for surveillance CTC within a CRC screening caused little burden • The vast majority never or only sometimes thought about their polyp(s) • In general, the burden of index and surveillance CTC were comparable • Awaiting results was more burdensome for surveillance than for index CTC.

Comparison of 64-Detector CT Colonography and Conventional Colonoscopy in the Detection of Colorectal Lesions.

BACKGROUND: Colon cancer is a leading cause of morbidity and mortality in developed countries. The early detection of colorectal cancer using screening programs is important for managing early-stage colorectal cancers and polyps. Modalities that allow examination of the entire colon are conventional colonoscopy, double contrast barium enema examination and multi-detector computed tomography (MDCT) colonography. OBJECTIVES: To compare CT colonography and conventional colonoscopy results and to evaluate the accuracy of CT colonography for detecting colorectal lesions. PATIENTS AND METHODS: In a prospective study performed at Gastroenterology and Radiology Departments of Medical Faculty of Eskisehir Osmangazi University, CT colonography and colonoscopy results of 31 patients with family history of colorectal carcinoma, personal or family history of colorectal polyps, lower gastrointestinal tract bleeding, change in bowel habits, iron deficiency anemia and abdominal pain were compared. Regardless of the size, CT colonography and conventional colonoscopy findings for all the lesions were cross - tabulated and the sensitivity, specificity, and positive and negative predictive values were calculated. To assess the agreement between CT colonography and conventional colonoscopy examinations, the Kappa coefficient of agreementt was used. Statistical analysis was performed by SPSS ver 15.0. RESULTS: Regardless of the size, MDCT colonography showed 83% sensitivity and 95% specificity, with a positive predictive value of 95% and a negative predictive value of 83% for the detection of colorectal polyps and masses. MDCT colonography displayed 92% sensitivity and 95% specificity, with a positive predictive value of 92% and a negative predictive value of 95% for polyps ≥ 10 mm. For polyps between 6mm and 9 mm, MDCT colonography displayed 75% sensitivity and 100% specificity, with a positive predictive value of 100% and a negative predictive value of 90%. For polyps ≤ 5 mm MDCT colonography displayed 88% sensitivity and 100% specificity with a positive predictive value of 100% and a negative predictive value of 95%. CONCLUSIONS: CT colonography is a safe and minimally invasive technique, a valuable diagnostic tool for examining the entire colon and a good alternative compared to other colorectal cancer screening tests because of its high sensitivity values in colorectal lesions over 1 cm.

Effect of Reducing Abdominal Compression during Prone CT Colonography on Ascending Colonic Rotation during Supine-to-Prone Positional Change.

OBJECTIVE: To determine the effect of reduced abdominal compression in prone position on ascending colonic movement during supine-to-prone positional change during CT colonography (CTC). MATERIALS AND METHODS: Eighteen consecutive patients who had undergone prone CTC scanning with cushion blocks placed under the chest and hip/thigh to reduce abdominal compression and had confirmed sessile polyps ≥ 6 mm in the well-distended, straight, mid-ascending colon, were included. Radial location along the ascending colonic luminal circumference (°) was measured for 24 polyps and 54 colonic teniae on supine and prone CTC images. The supine-to-prone change ranging between -180° and +180° (- and + for internal and external colonic rotations, respectively), was determined. In addition, possible causes of any ascending colonic rotations were explored. RESULTS: Abdominal compression during prone CTC scanning completely disappeared with the use of cushion blocks in 17 of 18 patients. However, some degrees of ascending colonic rotation were still observed, with the radial location changes of -22° to 61° (median, 13.9°) for the polyps and similar degrees for teniae. Fifty-four percent and 56% of polyps and teniae, respectively, showed changes > 10°. The radial location change of the polyps was significantly associated with the degree of anterior shift of the small bowel and mesentery (r = 0.722, p < 0.001) and the degree of posterior displacement of the ascending colon (r = 0.566, p = 0.004) during supine-to-prone positional change. CONCLUSION: Ascending colonic rotation upon supine-to-prone positional change during CTC, mostly in the form of external rotation, is not eliminated by removing abdominal compression in prone position.

Computer tomography colonography participation and yield in patients under surveillance for 6-9 mm polyps in a population-based screening trial.

PURPOSE: Surveillance CT colonography (CTC) is a viable option for 6-9 mm polyps at CTC screening for colorectal cancer. We established participation and diagnostic yield of surveillance and determined overall yield of CTC screening. MATERIAL AND METHODS: In an invitational CTC screening trial 82 of 982 participants harboured 6-9 mm polyps as the largest lesion(s) for which surveillance CTC was advised. Only participants with one or more lesion(s) ≥6 mm at surveillance CTC were offered colonoscopy (OC); 13 had undergone preliminary OC. The surveillance CTC yield was defined as the number of participants with advanced neoplasia in the 82 surveillance participants, and was added to the primary screening yield. RESULTS: Sixty-five of 82 participants were eligible for surveillance CTC of which 56 (86.2 %) participated. Advanced neoplasia was diagnosed in 15/56 participants (26.8 %) and 9/13 (69.2 %) with preliminary OC. Total surveillance yield was 24/82 (29.3 %). No carcinomas were detected. Adding surveillance results to initial screening CTC yield significantly increased the advanced neoplasia yield per 100 CTC participants (6.1 to 8.6; p < 0.001) and per 100 invitees (2.1 to 2.9; p < 0.001). CONCLUSION: Surveillance CTC for 6-9 mm polyps has a substantial yield of advanced adenomas and significantly increased the CTC yield in population screening. KEY POINTS: • The participation rate in surveillance CT colonography (CTC) is 86 %. • Advanced adenoma prevalence in a 6-9 mm CTC surveillance population is high. • Surveillance CTC significantly increases the yield of population screening by CTC. • Surveillance CTC for 6-9 mm polyps is a safe strategy. • Surveillance CTC is unlikely to yield new important extracolonic findings.

Colon Capsule Endoscopy: Where Are We and Where Are We Going

Colon capsule endoscopy (CCE) is a noninvasive technique for diagnostic imaging of the colon. It does not require air inflation or sedation and allows minimally invasive and painless colonic evaluation. The role of CCE is rapidly evolving; for example, for colorectal screening (colorectal cancer [CRC]) in average-risk patients, in patients with an incomplete colonoscopy, in patients refusing a conventional colonoscopy, and in patients with contraindications for conventional colonoscopy. In this paper, we comprehensively review the technical characteristics and procedure of CCE and compare CCE with conventional methods such as conventional colonoscopy or computed tomographic colonography. Future expansion of CCE in the area of CRC screening for the surveillance of polyps and adenomatous lesions and for assessment of inflammatory bowel disease is also discussed.

Effect of Reducing Abdominal Compression during Prone CT Colonography on Ascending Colonic Rotation during Supine-to-Prone Positional Change

OBJECTIVE: To determine the effect of reduced abdominal compression in prone position on ascending colonic movement during supine-to-prone positional change during CT colonography (CTC). MATERIALS AND METHODS: Eighteen consecutive patients who had undergone prone CTC scanning with cushion blocks placed under the chest and hip/thigh to reduce abdominal compression and had confirmed sessile polyps > or = 6 mm in the well-distended, straight, mid-ascending colon, were included. Radial location along the ascending colonic luminal circumference (degrees) was measured for 24 polyps and 54 colonic teniae on supine and prone CTC images. The supine-to-prone change ranging between -180degrees and +180degrees (- and + for internal and external colonic rotations, respectively), was determined. In addition, possible causes of any ascending colonic rotations were explored. RESULTS: Abdominal compression during prone CTC scanning completely disappeared with the use of cushion blocks in 17 of 18 patients. However, some degrees of ascending colonic rotation were still observed, with the radial location changes of -22degrees to 61degrees (median, 13.9degrees) for the polyps and similar degrees for teniae. Fifty-four percent and 56% of polyps and teniae, respectively, showed changes > 10degrees. The radial location change of the polyps was significantly associated with the degree of anterior shift of the small bowel and mesentery (r = 0.722, p < 0.001) and the degree of posterior displacement of the ascending colon (r = 0.566, p = 0.004) during supine-to-prone positional change. CONCLUSION: Ascending colonic rotation upon supine-to-prone positional change during CTC, mostly in the form of external rotation, is not eliminated by removing abdominal compression in prone position.

Diagnóstico de neoplasia colorrectal: descripción de hallazgos en colonoscopia virtual y convencional / Diagnosis of Colorectal Neoplasia: Description of Findings On Virtual Colonoscopy And Conventional Colonoscopy

Introducción: La colonoscopia virtual surge como método diagnóstico en las diferentes patologías del colon. Objetivos: Describir y comparar los hallazgos de la colonoscopia convencional y la virtual relacionados con la presencia de neoplasias y sus características morfológicas de tamaño y localización, en pacientes con sospecha de patología de colon. Métodos: Estudio descriptivo de registro de casos clínicos. Se incluyeron 23 pacientes remitidos al servicio de gastroenterología para realización de colonoscopia, durante septiembre de 2007 y mayo de 2008. Los pacientes fueron llevados a colonoscopia virtual y, posteriormente, a colonoscopia óptica; los hallazgos fueron clasificados por un radiólogo y un gastroenterólogo, respectivamente, según su localización en los diferentes segmentos del colon, así como el tamaño, el tipo de lesión en mucosa, submucosa, carcinomas y lesiones extrínsecas. Resultados: El grado de concordancia de los dos procedimientos para el diagnóstico de pólipos fue de 76 %. Se encontró que la colonoscopia virtual tiene una sensibilidad para el diagnóstico de pólipos de 85,7 % IC (52,6-100) y un valor predictivo negativo de 92,9 % IC (75,8-100), valores considerados importantes, pero con amplios intervalos de confianza atribuidos a la poca cantidad de pacientes. Conclusiones: En el presente estudio se encontró un alto valor predictivo negativo, lo que hace que la colonoscopia virtual pueda ser el método diagnóstico inicial de elección en el tamizaje de las patologías colorrectales. En caso de ser negativa, se descarta patología; si es positiva, el método diagnóstico a seguir para confirmar los hallazgos sería la colonoscopia directa.

Introduction: Virtual colonoscopy emerges as a new diagnostic method to study the pathology that affects the colon. Objectives: To describe and compare the findings of conventional colonoscopy and virtual colonoscopy related to the presence of a neoplasia according to its morphology, size and location in patients suspected of having colonic pathology. Material and Methods: Descriptive study of the review of clinical cases. 23 patients submitted to the gastroenterology service between September 2007 and May 2008 for a conventional colonoscopy were included. The patients were taken to virtual colonoscopy and, subsequently, to optical colonoscopy; the findings were classified by a radiologist and a gastroenterologist, respectively, according to its location in the different segments of the colon, as well as size, the type of lesion in the mucous and submucous membrane, carcinomas and extrinsic lesions. Results: The degree of concordance between the two procedures on the diagnosis of polyps was 76%. Virtual colonoscopy had 85.7% sensibility (IC 52.6-100) and a negative predictive value of 92.9% (IC 75.8-100) for the diagnosis of polyps. These are considered important findings, but with wide intervals of confidence due to the small quantity of patients. Conclusion: In this study we found a high negative predictive value, which means that virtual colonoscopy could be the initial diagnostic method of choice in the screening of colorectal pathologies. In case it is negative, pathology is ruled out. If it is positive, the diagnosis method to follow in order to confirm the findings would be direct colonoscopy.

Value of CT virtual colonoscopy in the diagnosis of colorectal diseases / 中国医师进修杂志

ObjectiveTo estimate the value of CT virtual colonoscopy (CTVC) and its image postprocessing techniques in the diagnosis of colorectal diseases.MethodsCTVC images of 84 patients with suspected colorectal diseases were retrospectively analyzed combined with multiple planar reconstruction (MPR),shaded surface display(SSD) and transparent image reconstruction.The location,size,shape and type of the lesions were analyzed and the images were compared with electronic colonoscopy and pathologic specimen finding.ResulltsFify-nine of 84 patients were diagnosed as coloretal cancer (23 cases with cancer in sigmoid colon,22 cases in rectum,11 cases in ascending colon and 3 cases in appendix),8 cases were porctopolypus,3 cases were multiple colonic diverticula,1 case was hemorrhoids,13 cases were normal.All the diagnosis was confirmed correct by operation pathology or clinic.ConclusionCTVC can show the shape and other features of colorectal diseases,and has important significance for clinical staging and surgical planning of colorectal cancer.

Korean Guidelines for Colorectal Cancer Screening and Polyp Detection

Colorectal cancer is the second most common cancer in males and the fourth most common in females in Korea. Since the most of colorectal cancer occur through the prolonged transformation of adenomas into carcinomas, early detection and removal of colorectal adenomas are one of the most effective methods to prevent colorectal cancer. Considering the increasing incidence of colorectal cancer and polyps in Korea, it is very important to establish Korean guideline for colorectal cancer screening and polyp detection. Korean Multi-Society Take Force developed the guidelines with evidence-based methods. Parts of the statements drawn by systematic reviews and meta-analyses. Herein we discussed the epidemiology of colorectal cancers and adenomas in Korea, optimal screening methods for colorectal cancer, and detection for adenomas including fecal occult blood tests, radiologic tests, and endoscopic examinations.

Korean Guidelines for Colorectal Cancer Screening and Polyp Detection

Colorectal cancer is the second most common cancer in males and the fourth most common in females in Korea. Since the most of colorectal cancer occur through the prolonged transformation of adenomas into carcinomas, early detection and removal of colorectal adenomas are one of the most effective methods to prevent colorectal cancer. Considering the increasing incidence of colorectal cancer and polyps in Korea, it is very important to establish Korean guideline for colorectal cancer screening and polyp detection. Korean Multi-Society Take Force developed the guidelines with evidence-based methods. Parts of the statements drawn by systematic reviews and meta-analyses. Herein we discussed the epidemiology of colorectal cancers and adenomas in Korea, optimal screening methods for colorectal cancer, and detection for adenomas including fecal occult blood tests, radiologic tests, and endoscopic examinations.

Korean Guidelines for Colorectal Cancer Screening and Polyp Detection / 대한소화기학회지

Colorectal cancer is the second most common cancer in males and the fourth most common in females in Korea. Since the most of colorectal cancer occur through the prolonged transformation of adenomas into carcinomas, early detection and removal of colorectal adenomas are one of the most effective methods to prevent colorectal cancer. Considering the increasing incidence of colorectal cancer and polyps in Korea, it is very important to establish Korean guideline for colorectal cancer screening and polyp detection. Korean Multi-Society Take Force developed the guidelines with evidence-based methods. Parts of the statements drawn by systematic reviews and meta-analyses. Herein we discussed the epidemiology of colorectal cancers and adenomas in Korea, optimal screening methods for colorectal cancer, and detection for adenomas including fecal occult blood tests, radiologic tests, and endoscopic examinations.

Performance of computed tomographic colonography for the screening of colorectal polyp in acromegalic patients: a prospective study / Desempenho da colonografia tomográfica computadorizada para o rastreamento de pólipo colorretal em pacientes acromegálicos: um estudo prospectivo

CONTEXT: Acromegalic patients have better chances to develop colorectal polyps and cancer and, considered a high-risk group, need to undergo frequent screening examinations. Moreover, in acromegalia, the increased bowel length and the intestinal loop complexity can lead to higher levels of technical difficulties and increase the risks of complications at conventional colonoscopy. Computed tomographic colonography, also known as virtual colonoscopy, is an innovative and secure technology which is revolutionizing the diagnosis of colon and rectum neoplasias. OBJECTIVE: To analyze computed tomographic colonography performance for the screening of colorectal polyps in acromegalic patients. METHODS: A prospective study of 21 asymptomatic acromegalic patients, 12 male and 9 female, average age 49, who underwent computed tomographic colonography and conventional colonoscopy. Computed tomographic colonography was performed with a GE Helical Multislice Computed Tomography Apparatus. Conventional colonoscopy was performed in the same day, without previous knowledge of the computed tomographic colonography diagnostics. The study evaluated the capacity of computed tomographic colonography to detect patients with colorectal polyps and identify each colorectal lesion described by the colonoscopy. RESULTS: In two patients (2/21), conventional colonoscopy was incomplete. However, in all patients computed tomographic colonography was complete. In Phase I ("per patient"), computed tomographic colonography diagnosed eight of the nine patients with colorectal polyps and showed 88 percent sensitivity, 75 percent specificity and 81 percent accuracy. In Phase II ("per polyp"), out of the 21 acromegalic patients included in this study, 12 presented normal findings at conventional colonoscopy. A total of 19 polyps were identified in 9 patients. Ten of the 19 polyps were smaller than 10 mm, and 9 were equal to or larger than 10 mm. Computed tomographic colonography...

CONTEXTO: Pacientes com acromegalia apresentam maiores chances de desenvolver pólipo e câncer colorretal e, sendo considerados integrantes do grupo de risco, necessitam serem submetidos aos exames de rastreamento. Por sua vez, na acromegalia, o maior comprimento do cólon e a formação de alças intestinais complexas podem prever maiores dificuldades técnicas e aumentar o risco em potencial de complicações durante o exame de colonoscopia convencional. A colonografia tomográfica computadorizada, também denominada colonoscopia virtual, é uma tecnologia inovadora e segura, que está revolucionando o diagnóstico das neoplasias do cólon e do reto. OBJETIVO: Analisar o desempenho da colonografia tomográfica computadorizada no rastreamento de pólipos colorretais em pacientes com acromegalia. Métodos - Estudo prospectivo com 21 pacientes acromegálicos, 12 do sexo masculino e 9 do sexo feminino, idade média de 49 anos, assintomáticos, submetidos a colonografia tomográfica computadorizada e colonoscopia convencional. A colonografia tomográfica computadorizada foi realizada com aparelho de tomografia computadorizada helicoidal multislice da marca GE. A colonoscopia convencional foi realizada, no mesmo dia, sem prévio conhecimento do diagnóstico da colonografia tomográfica computadorizada. O estudo avaliou a capacidade da colonografia tomográfica computadorizada para detectar pacientes acromegálicos com pólipos colorretais e a identificação de cada lesão colorretal descrita pela colonoscopia. RESULTADOS: Em dois pacientes (2/21) a colonoscopia convencional foi incompleta. Entretanto, em todos os pacientes a colonografia tomográfica computadorizada foi completa na avaliação colorretal. Na primeira fase ("por paciente"), a colonografia tomográfica computadorizada diagnosticou oito de nove pacientes com pólipos colorretais e mostrou 88 por cento de sensibilidade, 75 por cento de especificidade e 81 por cento de precisão. Na segunda fase ("por pólipo")...

Avaliação do desempenho da colonografia tomográfica computadorizada (colonoscopia virtual) no diagnóstico de pólipos colorretais / Evaluation of computed tomographic colonography for detection of colorectal polyps

RACIONAL: A colonografia tomográfica computadorizada tem sido proposta como teste substituto da colonoscopia para o diagnóstico de pólipos colorretais em programas de rastreamento de câncer de intestino grosso. OBJETIVO: Avaliar o desempenho da colonografia tomográfica computadorizada na detecção de pólipos colorretais, considerando a colonoscopia como padrão-ouro. MÉTODOS: Foram estudados 20 pacientes com alto risco para neoplasia colorretal (14 homens e 6 mulheres com idades médias de 55 e 59 anos, respectivamente). A colonografia tomográfica computadorizada foi realizada até 3 horas antes da colonoscopia. Um cateter com balão foi introduzido no reto com insuflação dos cólons e do reto com ar ambiente até que fosse obtida distensão satisfatória dos mesmos. Para otimizar a distensão colônica, minimizar artefatos decorrentes da peristalse e diminuir o espasmo, foram administrados 20 mg de hioscina intravenosa imediatamente antes do exame radiológico. RESULTADOS: A imagem radiológica do cólon foi considerada de qualidade satisfatória em todos os casos. A colonoscopia detectou o total de 85 pólipos em 19 dos 20 pacientes (95 por cento). Todos os pólipos observados foram removidos e encaminhados para exame anatomopatológico. A colonografia tomográfica computadorizada identificou 8 dos 10 pólipos com diâmetros > 10 mm (80 por cento), 2 dos 19 com diâmetro entre 5 e 9 mm (18,2 por cento), e apenas 1 dos 53 <5 mm (9,1 por cento). Dos 43 pólipos adenomatosos, 17 eram > 5 mm. Destes, 8 (47 por cento) foram corretamente identificados pela colonografia tomográfica computadorizada. Nenhuma das neoplasias com diâmetros <5mm foi observada no exame radiológico. Dezenove dos 20 pacientes (95 por cento) submetidos a ambos os testes prefeririam submeter-se a nova colonoscopia, ao invés de uma colonografia tomográfica computadorizada, na eventualidade hipotética de ser necessário repetir um dos dois testes. CONCLUSÃO: Para pacientes com risco aumentado...

BACKGROUND: Computed tomographic colonography has been proposed for detection of colorectal polyps instead of colonoscopy in colorectal cancer screening programs. AIM: To evaluate the performance of computed tomographic colonography in the detection of colorectal polyps with colonoscopy used as the gold standard. METHODS: We prospectively studied 20 patients at high risk for colorectal neoplasia (14 men and 6 women; mean age, 55 years and 59 years). Computed tomographic colonography was performed immediately before colonoscopy. We inserted a rectal balloon catheter and insufflated the colon with room air to the level that a good distension was observed. Twenty milligrams of hioscin was given immediately before computed tomographic imaging of the abdomen and pelvis in order to minimize the degree of smooth-muscle spasm and peristalsis and to reduce the patient's discomfort. RESULTS: Computed tomographic colonography images were considered satisfactory in all cases. Colonoscopy detected 85 polyps in 19 of 20 patients (95 percent). All the observed polyps were successfully removed and examined histologically. The radiological examination correctly identified 8 of 10 polyps 10 mm or more in diameter, 2 of 19 (18,2 percent) with 5-9 mm, and just 1 of 53 <5mm (9,1 percent). Seventeen of the 43 adenomatous polyps were > 5 mm. Eight (47 percent) were correctly identified on computed tomographic colonography. None of the neoplasias <5 mm were identified on colonography. Nineteen patients preferred colonoscopy in the event of having to repeat on of the two examinations. CONCLUSION: For the detection of colorectal polyps, computed tomographic colonography seems to be useful only when the result is positive, as the negative results of this examination cannot eliminate the presence of these lesions.