scholarly journals CT- and MR Colonography

2002 ◽  
Vol 91 (4) ◽  
pp. 322-327 ◽  
Author(s):  
M. P. Achiam ◽  
S. Bülow ◽  
J. Rosenberg
Keyword(s):  
Colorectal Cancer ◽  
Bowel Preparation ◽  
High Sensitivity ◽  
Diagnostic Methods ◽  
Diagnostic Colonoscopy ◽  
Mr Colonography ◽  
Non Invasive ◽  
Processing Power ◽  
Major Disadvantage ◽  
Incidence And Mortality

Background: Colorectal cancer is the second most frequent cancer and adenomas are widely accepted as precursors to colorectal cancer. Diagnosis and removal of adenomas are recommended to reduce cancer incidence and mortality. The current diagnostic methods include sigmoidoscopy and colonoscopy. Lately, CT- and MR colonography have emerged as non-invasive methods for colon imaging. Methods: At present, CTC and MRC require bowel preparation. However, preliminary studies have been carried out without colon preparation. After the colon has been filled with air or contrast, the patient is scanned in the supine and prone positions. Data are then downloaded to a workstation for post processing and image-analysis. Results: Results have shown a high sensitivity and specificity for polyps ≥ 10 mm, comparable to the sensitivity of conventional colonoscopy and superior to double contrast barium enema. Conclusions: With the exponential development in computer processing power, CT- and MR colonography holds the promise for future colon examination with the advantages of non-invasiveness, no need for sedation, and probably no bowel preparation. major disadvantage, however, is the radiation dose during CT colonography. Future developments with the use of “intelligent” computers, better resolution and faster examinations will make CT and/or MR colonography realistic options to replace conventional diagnostic colonoscopy.

scholarly journals A prospective comparative study of detection of colonic polyposis by magnetic resonance colonography versus conventional colonoscopy

2019 ◽  
Vol 6 (9) ◽  
pp. 3258
Author(s):  
Kada Venkata Ramana ◽  
Tripuraneni Rajesh Kumar
Keyword(s):  
Colorectal Cancer ◽  
Magnetic Resonance ◽  
Positive Predictive Value ◽  
Negative Predictive Value ◽  
Predictive Value ◽  
Precancerous Lesion ◽  
Mr Colonography ◽  
Non Invasive ◽  
Magnetic Resonance Colonography ◽  
Incidence And Mortality

Background: Colorectal cancer mostly arises from adenomatous polyp and the transition time to convert into carcinoma is around ten years. As the progress to adenocarcinoma is a slow process so, early detection and endoscope resection is claimed to be effective in decreasing incidence and mortality by colorectal cancer. MR colonography is a non-invasive method for evaluating entire colon. It can detect precancerous lesion, cancer and staging. It is non-invasive tool for screening. Acceptability of the patient is better for MR colonography.Methods: Present study is a prospective comparative evaluation of magnetic resonance colonography verses colonoscopy conducted in the Department of Radiology, Konaseema Institute of Medical Science, and other establishments from August 2015 to January 2018. The sample size was calculated to be 112. Specificity, sensitivity and predictive value were calculated by medical statistical software.Results: For all size of tumours, sensitivity was 85.71%, specificity was 92.85%, positive predictive value was 92.30%, negative predictive value was 86.66% and accuracy was 94.34%. The positive predictive value was 90.00% negative predictive value was 92.68% and accuracy was 92.16%. For 1 mm to 4 mm size of polyp the sensitive was 28.57%, specificity was 92.31%, positive predictive value was 66.67%, negative predictive value was 70.59% and accuracy was 70%.Conclusions: In present study we have found that there was male predominance in patient and gastrointestinal bleeding was common clinical presentation. We have also observed that all size of poly MR colonography as having sensitivity and specificity around 90% but MR colonography is highly sensitive and specific for polyp size above 8mm but it is less sensitive for size below 4 mm. 

scholarly journals Metal Oxide Nanorods-Based Sensor Array for Selective Detection of Biomarker Gases

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1922
Author(s):  
Gwang Su Kim ◽  
Yumin Park ◽  
Joonchul Shin ◽  
Young Geun Song ◽  
Chong-Yun Kang
Keyword(s):  
Real Time ◽  
Sensor Array ◽  
High Sensitivity ◽  
Gas Analysis ◽  
Diagnostic Methods ◽  
Real Time Monitoring ◽  
Non Invasive ◽  
Sensitivity And Selectivity ◽  
Breath Gas Analysis ◽  
Angle Method

The breath gas analysis through gas phase chemical analysis draws attention in terms of non-invasive and real time monitoring. The array-type sensors are one of the diagnostic methods with high sensitivity and selectivity towards the target gases. Herein, we presented a 2 × 4 sensor array with a micro-heater and ceramic chip. The device is designed in a small size for portability, including the internal eight-channel sensor array. In2O3 NRs and WO3 NRs manufactured through the E-beam evaporator’s glancing angle method were used as sensing materials. Pt, Pd, and Au metal catalysts were decorated for each channel to enhance functionality. The sensor array was measured for the exhaled gas biomarkers CH3COCH3, NO2, and H2S to confirm the respiratory diagnostic performance. Through this operation, the theoretical detection limit was calculated as 1.48 ppb for CH3COCH3, 1.9 ppt for NO2, and 2.47 ppb for H2S. This excellent detection performance indicates that our sensor array detected the CH3COCH3, NO2, and H2S as biomarkers, applying to the breath gas analysis. Our results showed the high potential of the gas sensor array as a non-invasive diagnostic tool that enables real-time monitoring.

scholarly journals The importance of colonoscopy bowel preparation for the detection of colorectal lesions and colorectal cancer prevention

2020 ◽  
Vol 08 (05) ◽  
pp. E673-E683 ◽  
Author(s):  
Prateek Sharma ◽  
Carol A. Burke ◽  
David A. Johnson ◽  
Brooks D. Cash
Keyword(s):  
Colorectal Cancer ◽  
Bowel Preparation ◽  
Clinical Importance ◽  
High Volume ◽  
High Quality ◽  
Crc Screening ◽  
Incidence And Mortality ◽  
Low Volume ◽  
Split Dosing ◽  
Bowel Preparations

Abstract Background and study aims Colonoscopy for colorectal cancer (CRC) screening has reduced CRC incidence and mortality and improved prognosis. Optimal bowel preparation and high-quality endoscopic technique facilitate early CRC detection.This review provides a narrative on the clinical importance of bowel preparation for colonoscopy and highlights available bowel preparations. Methods A PubMed search was conducted through June 2019 to identify studies evaluating clinical outcomes, efficacy, safety, and tolerability associated with bowel preparation for CRC screening-related colonoscopy. Results Selecting the optimal bowel preparation regimen is based on considerations of efficacy, safety, and tolerability, in conjunction with individual patient characteristics and preferences. Available bowel preparations include high-volume (4 L) and low-volume (2 L and 1 L), polyethylene glycol (PEG) solutions, sodium sulfate, sodium picosulfate/magnesium oxide plus anhydrous citric acid, sodium phosphate tablets, and the over-the-counter preparations magnesium citrate and PEG-3350. These preparations may be administered as a single dose on the same day or evening before, or as two doses administered the same day or evening before/morning of colonoscopy. Ingesting at least half the bowel preparation on the day of colonoscopy (split-dosing) is associated with higher adequate bowel preparation quality versus evening-before dosing (odds ratio [OR], 2.5; 95 % confidence interval [CI], 1.9−3.4). Conclusions High-quality bowel preparation is integral for optimal CRC screening/surveillance by colonoscopy. Over the last 30 years, patients and providers have gained more options for bowel preparation, including low-volume agents with enhanced tolerability and cleansing quality that are equivalent to 4 L preparations. Split-dosing is preferred for achieving a high-quality preparation.

scholarly journals Clinical Validation Results of an Innovative Non-Invasive Device for Colorectal Cancer Preventive Screening through Fecal Exhalation Analysis

Cancers ◽  
2020 ◽  
Vol 12 (6) ◽  
pp. 1471
Author(s):  
Giulia Zonta ◽  
Cesare Malagù ◽  
Sandro Gherardi ◽  
Alessio Giberti ◽  
Alessandro Pezzoli ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Low Cost ◽  
Occult Blood ◽  
Machine Learning Techniques ◽  
Fecal Occult Blood ◽  
Clinical Validation ◽  
Non Invasive ◽  
Fecal Occult ◽  
Incidence And Mortality

Screening is recommended to reduce both incidence and mortality of colorectal cancer. Currently, many countries employ fecal occult blood test (FOBT). In Emilia-Romagna (Italy), since 2005, FOBT immunochemical version (FIT) is performed every two years on people aged between 50 and 69 years. A colonoscopy is then carried out on those who are FIT positive. However, FIT shows approximately 65% false positives (non-tumoral bleedings), leading to many negative colonoscopies. The use of an economic and easy-to-use method to check FOBT-positives will improve screening effectiveness, reducing costs to the national health service. This work illustrates the results of a three-year clinical validation protocol (started in 2016) of a patented device composed of a core of nanostructured gas sensors. This device was designed to identify CRC presence by fecal volatile compounds, with a non-invasive, in vitro and low-cost analysis. Feces are, in fact, affected by tumor-volatile biomarkers, produced by cellular peroxidation and metabolic alterations. The protocol consisted in the analysis of fecal samples of FIT-positive subjects, using colonoscopy as a gold standard. A total of 398 samples were analyzed with machine learning techniques, leading to a sensitivity and specificity of 84.1% and 82.4%, respectively, and a positive predictive value of 72% (25–35% for FIT).

Feasibility and Potential of MR-Colonography for Evaluating Colorectal Cancer

Swiss Surgery ◽  
2002 ◽  
Vol 8 (1) ◽  
pp. 21-24 ◽  
Author(s):  
Meier ◽  
Wildermuth
Keyword(s):  
Colorectal Cancer ◽  
Bowel Preparation ◽  
Virtual Colonoscopy ◽  
Colorectal Polyps ◽  
Data Sets ◽  
Diagnostic Modality ◽  
Technical Problems ◽  
Mr Colonography ◽  
Synchronous Carcinoma ◽  
3D Data

Background: MR-Colonography (MRC) based on MR-imaging is a relatively new diagnostic modality for diagnosing colorectal polyps. The aim of this experimental study was to evaluate its performance in detecting and staging colorectal cancer..Method: 23 patients with proven colorectal cancer underwent MR-Colonography one day prior to operation after standard bowel preparation. The colon was filled with a diluted gadolinium enema. Coronal sections were acquired in prone and supine. Virtual colonoscopy (VC) was processed from the acquired 3D data sets and MRC was interactively analysed together with VC. The findings were correlated with colonoscopic and pathology results..Results: A complete MRC was achieved in 21 patients (92%), two patients (8%) could not be conclusively evaluated due to insufficient bowel preparation or technical problems. No complications were observed. Compared to colonoscopy all 23 carcinomas were detected. No lesion >= 8mm was missed. In one patient a synchronous carcinoma was newly diagnosed. This lesion was missed by colonoscopy since the distal tumour was endoscopically unpassable. In total eight (33%) colonoscopies were incomplete..Conclusion: MRC offers a new and promising diagnostic tool for colorectal cancer. It is particularly valuable when colonoscopy is incomplete. It improves preoperative planning and it holds the potential as an all-in-one investigation including local and liver staging in combination with conventional MRI.

scholarly journals DNA methylation markers detected in blood, stool, urine, and tissue in colorectal cancer: a systematic review of paired samples

2020 ◽  
Author(s):  
Eivor Alette Laugsand ◽  
Siv Sellæg Brenne ◽  
Frank Skorpen
Keyword(s):  
Colorectal Cancer ◽  
Dna Methylation ◽  
Data Extraction ◽  
Meta Analysis ◽  
Methylation Status ◽  
High Sensitivity ◽  
Liquid Biopsies ◽  
Non Invasive ◽  
Paired Samples

Abstract Purpose Methylated cell-free DNA in liquid biopsies are promising non-invasive biomarkers for colorectal cancer (CRC). Optimal markers would have high sensitivity and specificity for early detection of CRC and could be detected in more than one type of material from the patient. We systematically reviewed the literature on DNA methylation markers of colorectal cancer, detected in more than one type of material, regarding their potential as contributors to a panel for screening and follow-up of CRC. Methods The databases MEDLINE, Web of Science, and Embase were systematically searched. Data extraction and review was performed by two authors independently. Agreement between methylation status in tissue and other materials (blood/stool/urine) was analyzed using the McNemar test and Cohen’s kappa. Results From the 51 included studies, we identified seven single markers with sensitivity ≥ 75% and specificity ≥ 90% for CRC. We also identified one promising plasma panel and two stool panels. The correspondence of methylation status was evaluated as very good for four markers, but only marginal for most of the other markers investigated (12 of 21). Conclusion The included studies reported only some of the variables and markers of interest and included few patients. Hence, a meta-analysis was not possible at this point. Larger, prospective studies must be designed to study the discordant detection of markers in tissue and liquid biopsies. When reporting their findings, such studies should use a standardized format.

scholarly journals A comparative study between placental alpha microglobulin-1 rapid immunoassay and standard diagnostic methods for detection of rupture of membranes

2018 ◽  
Vol 7 (5) ◽  
pp. 1813
Author(s):  
Hemant Deshpande ◽  
Umesh Sabale ◽  
C. S. Madkar ◽  
Anuja Bobe
Keyword(s):  
False Negative ◽  
High Sensitivity ◽  
Diagnostic Methods ◽  
Step Test ◽  
Non Invasive ◽  
Emergency Cesarean ◽  
One Step ◽  
Conventional Methods ◽  
Sensitivity Specificity ◽  
Very High

Background: To determine the efficacy of an immunoassay to measure levels of placental alpha-microglobulin-1 in cervico-vaginal secretions.Methods: 100 ANC cases admitted in Dr D. Y. Patil Hospital with symptoms of rupture of membranes during study period. Inclusion criteria-Pregnant women who presented with symptoms of ROM either in labour or not in labour, gestational age from 28 weeks onwards and who have given consent.Results: In 9 cases, the immunoassay test was negative, in 91 cases, it was positive and in one case, the liquor had a lot of meconium, the woman had to undergo an emergency cesarean section. This patient was deemed to have a false negative result by the test. Pooling was positive in 87 cases, nitrazine test in 86 cases and ferning in 88 cases. Hence, in comparison to immunoassay test which had 100% specificity and 98.91% sensitivity due to incomplete evaluation, nitrazine test had 95.58% sensitivity and 100% specificity, Pooling has 97.79% sensitivity and 100% specificity, whereas ferning has 98.34% sensitivity and 100% specificity.Conclusions: The PAMG1 is a non-invasive, rapid, one step test with very high sensitivity, specificity and accuracy as compared to the conventional methods together and also individually. Preforming this test instead of conventional methods can aid the early detection of rupture of membranes and largely affect the outcome of maternal and fetal health as timely decision can be taken once diagnosis is confirmed.

scholarly journals Highly-specific early detection of colorectal cancer by novel non-invasive serum methylation biomarkers

2021 ◽  
Author(s):  
Maria Gallardo-Gomez ◽  
Mar Rodriguez-Girondo ◽  
Nuria Planell ◽  
Sebastian Moran ◽  
Luis Bujanda ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Early Detection ◽  
Blood Test ◽  
Serum Samples ◽  
Screening Programs ◽  
Non Invasive ◽  
Incidence And Mortality ◽  
Sample Pooling ◽  
Immunochemical Test ◽  
Advanced Adenomas

Early detection has proven to be the most effective strategy to reduce the incidence and mortality of colorectal cancer (CRC). Nevertheless, most current screening programs suffer from low participation rates. A blood test may improve both the adherence to screening and the selection to colonoscopy. In this study, we conducted a serum-based discovery and validation of cfDNA methylation biomarkers for CRC screening in a multicentre cohort of 453 serum samples including healthy controls, benign pathologies, advanced adenomas (AA), and CRC. First, we performed an epigenome-wide methylation analysis with the MethylationEPIC array using a sample pooling approach, followed by a robust prioritization of candidate biomarkers for the detection of advanced neoplasia (AN: AA and CRC). Then, candidate biomarkers were validated by pyrosequencing in independent individual cfDNA samples. We report GALNT9, UPF3A, WARS, and LDB2 as new non-invasive biomarkers for the early detection of AN. The combination of GALNT9/UPF3A by logistic regression discriminated AN with 78.8% sensitivity and 100% specificity, outperforming the commonly used fecal immunochemical test and the methylated SEPT9 blood test. Overall, our results suggest that the combination methylated GALNT9/UPF3A has the potential to serve as a highly specific and sensitive blood-based test for screening and early detection of CRC.

scholarly journals Medical needs related to the endoscopic technology and colonoscopy for colorectal cancer diagnosis

BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Juan Francisco Ortega-Morán ◽  
Águeda Azpeitia ◽  
Luisa F. Sánchez-Peralta ◽  
Luis Bote-Curiel ◽  
Blas Pagador ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Cancer Diagnosis ◽  
Bowel Preparation ◽  
Visual Information ◽  
New Technologies ◽  
Optical Systems ◽  
Polyp Detection ◽  
Cad System ◽  
Medical Needs ◽  
Incidence And Mortality

Abstract Background The high incidence and mortality rate of colorectal cancer require new technologies to improve its early diagnosis. This study aims at extracting the medical needs related to the endoscopic technology and the colonoscopy procedure currently used for colorectal cancer diagnosis, essential for designing these demanded technologies. Methods Semi-structured interviews and an online survey were used. Results Six endoscopists were interviewed and 103 were surveyed, obtaining the demanded needs that can be divided into: a) clinical needs, for better polyp detection and classification (especially flat polyps), location, size, margins and penetration depth; b) computer-aided diagnosis (CAD) system needs, for additional visual information supporting polyp characterization and diagnosis; and c) operational/physical needs, related to limitations of image quality, colon lighting, flexibility of the endoscope tip, and even poor bowel preparation. Conclusions This study shows some undertaken initiatives to meet the detected medical needs and challenges to be solved. The great potential of advanced optical technologies suggests their use for a better polyp detection and classification since they provide additional functional and structural information than the currently used image enhancement technologies. The inspection of remaining tissue of diminutive polyps (< 5 mm) should be addressed to reduce recurrence rates. Few progresses have been made in estimating the infiltration depth. Detection and classification methods should be combined into one CAD system, providing visual aids over polyps for detection and displaying a Kudo-based diagnosis suggestion to assist the endoscopist on real-time decision making. Estimated size and location of polyps should also be provided. Endoscopes with 360° vision are still a challenge not met by the mechanical and optical systems developed to improve the colon inspection. Patients and healthcare providers should be trained to improve the patient’s bowel preparation.

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