Technical and Administrative Advances to Promote Sustainable Radiology.

Climate change mandates that we take steps to understand and mitigate the negative environmental consequences of the practice of health care, so that health care advances sustainably. In this article, the authors review and discuss a sample of technical and administrative advances required to align the practice of radiology with principles of environmental sustainability.

The Environmental, Social, Governance Movement and Radiology: Opportunities and Strategy.

The environmental, social, governance (ESG) movement has come to health care organizations, in part through the Biden administration's challenge to them to reduce greenhouse gas emissions by 50% by 2030 and achieve net zero emissions by 2050, in support of more robust environmental sustainability. Radiology practices should become knowledgeable about ESG concepts and look for opportunities that are meaningful and achievable to support their host organizations' ESG efforts. Examples of initiatives to support improved environmental sustainability include selecting the least energy intensive imaging method for a given diagnosis, shutting down equipment in standby mode, sourcing energy from renewable sources, and reducing waste through recycling.

Diagnostic accuracy of laxative-free computed tomographic colonography for detection of adenomatous polyps in asymptomatic adults: a prospective evaluation.

Background: Colon screening by optical colonoscopy (OC) or computed tomographic colonography (CTC) requires a laxative bowel preparation, which inhibits screening participation.

Objective: To assess the performance of detecting adenomas 6 mm or larger and patient experience of laxative-free, computer-aided CTC.

Design: Prospective test comparison of laxative-free CTC and OC.

Mosaic decomposition: an electronic cleansing method for inhomogeneously tagged regions in noncathartic CT colonography.

Electronic cleansing (EC) is a method that segments fecal material tagged by an X-ray-opaque oral contrast agent in computed tomographic colonography (CTC) images, and effectively removes the material for digitally cleansing the colon. In this study, we developed a novel EC method, called mosaic decomposition (MD), for reduction of the artifacts due to incomplete cleansing of inhomogeneously tagged fecal material in CTC images, especially in noncathartic CTC images. In our approach, the entire colonic region, including the residual fecal regions, was first decomposed into a set of local homogeneous regions, called tiles, after application of a 3-D watershed transform to the CTC images.

Debate: diminutive polyps noted at CT colonography need not be reported.

Colorectal polyps less than 6 mm in size pose a negligible risk to the development of colorectal carcinoma. The sensitivity and specificity for detection of diminutive lesions on all available examinations including CT colonography (CTC) and optical colonoscopy (OC) is relatively low. In the context of regular screening, the low clinical significance and slow to negligible growth of diminutive polyps, as well as the low detection performance of CTC and OC for these lesions, would contribute to wasted health care resource and excess morbidity if each diminutive polyp were referred for potential resection.

Informatics in radiology: Electronic cleansing for noncathartic CT colonography: a structure-analysis scheme.

Computed tomographic (CT) colonography performed after tagging of fecal matter but without a cathartic agent, or noncathartic CT colonography (also known as laxative-free CT colonography), is regarded as a promising next-generation technique for reducing or eliminating the discomfort associated with cathartic bowel preparation, which is the major barrier to undergoing colon cancer screening. Electronic cleansing is an emerging technique for the removal of tagged fecal materials from CT colonographic images. Three major electronic cleansing artifacts--soft-tissue degradation, pseudo-soft-tissue structures, and incomplete cleansing--severely impair the quality of electronically cleansed noncathartic CT colonographic images and limit the diagnostic utility of this modality.

A case tracking system with electronic medical record integration to automate outcome tracking for radiologists.

Radiologists make many diagnoses, but only sporadically get feedback on the subsequent clinical courses of their patients. We have created a web-based application that empowers radiologists to create and maintain personal databases of cases of interest. This tool integrates with existing information systems to minimize manual input such that radiologists can quickly flag cases for further follow-up without interrupting their clinical work.

Comparative evaluation of the fecal-tagging quality in CT colonography: barium vs. iodinated oral contrast agent.

Rationale And Objectives: The purpose of this evaluation was to compare the tagging quality of a barium-based regimen with that of iodine-based regimens for computed tomographic (CT) colonography.

Materials And Methods: Tagging quality was assessed retrospectively in three different types of fecal-tagging CT colonographic cases: 24 barium-based cases, 22 nonionic iodine-based cases, and 24 ionic iodine-based cases. For the purpose of evaluation, the large intestine was divided into six segments, and the tagging homogeneity of a total of 420 segments (70 patients) was graded by three blinded readers from 0 (heterogeneous) to 4 (homogeneous).

Structure-analysis method for electronic cleansing in cathartic and noncathartic CT colonography.

Electronic cleansing (EC) is an emerging method for segmentation of fecal material in CT colonography (CTC) that is used for reducing or eliminating the requirement for cathartic bowel preparation and hence for improving patients' adherence to recommendations for colon cancer screening. In EC, feces tagged by an x-ray-opaque oral contrast agent are removed from the CTC images, effectively cleansing the colon after image acquisition. Existing EC approaches tend to suffer from the following cleansing artifacts: degradation of soft-tissue structures because of pseudo-enhancement caused by the surrounding tagged fecal materials, and pseudo soft-tissue structures and false fistulas caused by partial volume effects at the boundary between the air lumen and the tagged regions, called the air-tagging boundary (AT boundary).

CT colonography: influence of 3D viewing and polyp candidate features on interpretation with computer-aided detection.

Purpose: To retrospectively determine if three-dimensional (3D) viewing improves radiologists' accuracy in classifying true-positive (TP) and false-positive (FP) polyp candidates identified with computer-aided detection (CAD) and to determine candidate polyp features that are associated with classification accuracy, with known polyps serving as the reference standard.

Materials And Methods: Institutional review board approval and informed consent were obtained; this study was HIPAA compliant. Forty-seven computed tomographic (CT) colonography data sets were obtained in 26 men and 10 women (age range, 42-76 years).

Tagging-based, electronically cleansed CT colonography: evaluation of patient comfort and image readability.

Purpose: To prospectively compare the homogeneity, adequacy, and patient acceptance of nonionic iodine-based regimens with those of a barium-based regimen for computed tomographic (CT) colonography with electronic subtraction cleansing.

Materials And Methods: After institutional review board approval and informed consent were obtained, 68 subjects (41 men (60%) men, 27 (40%) women; mean age, 60 years +/- 6 [standard deviation]) with average or moderate risk factors for development of colorectal carcinoma were recruited and placed into three study groups. Group 1 (n = 25) ingested 150-mL aliquots of 2% barium sulfate suspension with meals and snacks for 48 hours prior to imaging, without other diet modification or a cathartic.

Polyp size at CT colonography after electronic subtraction cleansing in an anthropomorphic colon phantom.

Purpose: To evaluate the effect of various bowel contrast material concentrations and subtraction software on size measurements of well-defined polyp lesions in a colon phantom at CT colonography.

Materials And Methods: Repeated scanning and a precise reference standard required the use of a colon phantom in which 21 polyps were randomly distributed. Two readers who had each reviewed computed tomographic (CT) colonographic images from more than 100 cases evaluated polyp size on images obtained when the phantom was partially filled with varying concentrations of contrast material, scanned by using CT colonography, and subjected to electronic subtraction cleansing.

Low-dose CT colonography in children: initial experience, technical feasibility, and utility.

Background: CT colonography (CTC) is utilized as a diagnostic tool in the detection of colon polyps and early colorectal cancer in adults. Large studies in the literature, although focused on adult populations, have shown CTC to be a safe, accurate, non-invasive technique.

Objective: We evaluated the technical feasibility of CTC in children using a low-dose technique.

Digital subtraction bowel cleansing for CT colonography using morphological and linear filtration methods.

We describe a method to perform postacquisition processing of computed tomography colonography (virtual colonoscopy) datasets that results in electronic removal of opacified, ingested bowel contents while reconstructing natural appearing boundaries of colon lumen and thereby permitting three-dimensional visual analyses of the resulting colon models.

An analysis of the potential impact of computed tomographic colonography (virtual colonoscopy) on colonoscopy demand.

Background And Aims: There has been much speculation about the potential impact on the use of conventional colonoscopy if "virtual" computed tomographic colonography (CTC) became a widely accepted modality for colorectal cancer (CRC) screening. However, no formal analysis of the impact of CTC on colonoscopy demand has been reported.

Methods: A mathematical model to predict colonoscopy demand based on several relevant input parameters was constructed.

CT colonography: digital subtraction bowel cleansing with mucosal reconstruction initial observations.

The authors evaluated a computed tomography (CT) colonographic technique with a combination of preexamination orally ingested positive contrast material and postacquisition image processing to subtract out the ingested opacified bowel contents. With this technique, rigorous physical purging of the bowel was not necessary before structural examination of the colon. With images obtained in 20 patients, two readers were able to correctly identify the majority of polyps confirmed at colonoscopy.