Bowel cleansing before CT colonography: comparison between two minimal-preparation regimens

Reporting of Participant Demographics in Clinical Trials Published in General Radiology Journals

OBJECTIVES

The reporting of research participant demographics provides insights into study generalizability. Our study aimed to determine the frequency at which participant age, sex/gender, race/ethnicity, and socioeconomic status (SES) are reported and used for subgroup analyses in radiology randomized controlled trials (RCTs) and their secondary analyses; as well as the study characteristics associated with, and the classification systems used for demographics reporting.

METHODS

RCTs and their secondary analyses published in 8 leading radiology journals between 2013 and 2021 were included. Associations between study characteristics and demographic reporting were tested with the chi-square goodness of fit test for categorical variables, Wilcoxon-Mann-Whitney test for impact factor, and logistic regression for publication year.

RESULTS

Among 432 included articles, 89.4% (386) reported age, 90.3% (390) sex/gender, 5.6% (24) race/ethnicity, and 3.0% (13) SES. Among articles that reported these demographics and were not specific to a subgroup, results were analyzed by age in 14.2% (55/386), sex/gender in 19.4% (66/340), race/ethnicity in 13.6% (3/22), and SES in 46.2% (6/13). Journal, impact factor, and last author continent were predictors of race/ethnicity and SES reporting. Funding was associated with race/ethnicity reporting. No study reported sex and gender separately, or documented transgender, nonbinary gender spectrum or intersex participants. A single category for race/ethnicity was used in 37.5% (9/24) of studies, consisting of either "White" or "Caucasian."

CONCLUSION

The reporting of participant demographics in radiology trials is variable and not always representative of the population diversity. Editorial guidelines on the reporting and analysis of participant demographics could help standardize practices.

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.

Effect of dose splitting of a low-volume bowel preparation macrogol-based solution on CT colonography tagging quality

Purpose

To compare examination quality and acceptability of three different low-volume bowel preparation regimens differing in scheduling of the oral administration of a Macrogol-based solution, in patients undergoing computed tomographic colonography (CTC). The secondary aim was to compare CTC quality according to anatomical and patient variables (dolichocolon, colonic diverticulosis, functional and secondary constipation).

Methods

One-hundred-eighty patients were randomized into one of three regimens where PEG was administered, respectively: in a single dose the day prior to (A), or in a fractionated dose 2 (B) and 3 days (C) before the examination. Two experienced radiologists evaluated fecal tagging (FT) density and homogeneity both qualitatively and quantitatively by assessing mean segment density (MSD) and relative standard deviation (RSD). Tolerance to the regimens and patient variables were also recorded.

Results

Compared to B and C, regimen A showed a lower percentage of segments with inadequate FT and a significantly higher median FT density and/or homogeneity scores as well as significantly higher MSD values in some colonic segments. No statistically significant differences were found in tolerance of the preparations. A higher number of inadequate segments were observed in patients with dolichocolon (p < 0.01) and secondary constipation (p < 0.01). Interobserver agreement was high for the assessment of both FT density (k = 0.887) and homogeneity (k = 0.852).

Conclusion

The best examination quality was obtained when PEG was administered the day before CTC in a single session. The presence of dolichocolon and secondary constipation represent a risk factor for the presence of inadequately tagged colonic segments.

A novel volume-reduced CT colonography regimen using hypertonic laxative (polyethylene glycol with ascorbic acid): randomized controlled trial

OBJECTIVES

The aim of this study is to investigate the feasibility of bowel preparation using a hypertonic laxative (polyethylene glycol with ascorbic acid, PEG + Asc) for CT colonography (CTC) and to examine the volume limit of laxative.

METHODS

In one institution, patients who met the indications for CTC were enrolled and randomly assigned to CTC with regimen A (800 ml PEG + Asc), B (600 ml PEG + Asc), or C (400 ml PEG + Asc). Sodium diatrizoate was given orally for fecal tagging. On the previous day, patients ate low-residue meals and took the assigned lavage solution after dinner. A reader blinded to the preparation graded residual stool/fluid and fecal tagging quality in six segments of the colorectum. The primary outcome was a proportion of colon segments without stool. One hundred twenty segments in 20 patients with each regimen were needed to show a non-inferiority margin of 15%, assuming 85% of no stool.

RESULTS

A total of 360 segments in 60 patients were analyzed. There were 83% of segments with no stool in regimen A, 89% in regimen B, and 88% in regimen C. Using the delta method, the 95% confidence interval of the risk difference (6.7%) between regimens A and B was - 2.2% to 15.6%, and the risk difference (5.0%) between regimens A and C was - 4.1% to 14%, both within the non-inferiority margin. Residual fluid and fecal tagging quality were also within the non-inferiority margin. No adverse events occurred.

CONCLUSIONS

A novel CTC regimen using hypertonic laxative demonstrated optimal colon cleansing effectiveness even with the lowest volume of laxative (UMIN000022851).

KEY POINTS

• A novel CTC regimen using a hypertonic laxative is feasible. • The lowest volume of laxative provides excellent colon imaging. • However, the lowest volume of laxative did not improve patient acceptance.

Computed tomographic colonography with a reduced dose of laxative using a novel barium sulfate contrast agent in Japan

PURPOSE

To test the tagging efficacy, patient acceptability, and accuracy of computed tomographic colonography (CTC) with a reduced dose of laxative using a novel barium sulfate (BaSO₄) contrast agent.

MATERIALS AND METHODS

CTC followed by optical colonoscopy (OC) was performed on 73 patients with positive results in fecal occult blood tests. They were administrated a BaSO₄ suspension and a magnesium citrate solution for bowel preparation. Patients completed a questionnaire about the acceptability of bowel preparation. Tagging efficacy was estimated using a novel categorization system, which classified all segments into 8 categories. The accuracy of detecting protruded lesions ≥ 6 mm was calculated from the comparison of CTC and OC results, using the latter as a reference standard.

RESULTS

Tagging efficacy was good in 77.3% of colonic segments where residue was observed. The acceptability of bowel preparation for CTC was significantly higher than that for OC. The sensitivity, specificity, and positive and negative predictive values were 0.778, 0.945, 0.824, and 0.929, respectively. All lesions ≥ 7 mm were successfully detected by CTC.

CONCLUSION

CTC with a reduced dose of laxative using a novel BaSO₄ contrast agent has a favorable tagging efficacy, patient acceptability, and accuracy.