Emergency Department Contrast Practices for Abdominal/Pelvic Computed Tomography—A National Survey and Comparison with the American College of Radiology Appropriateness Criteria®

Acute Colonic Diverticulitis: CT Findings, Classifications, and a Proposal of a Structured Reporting Template

Acute colonic diverticulitis (ACD) is the most common complication of diverticular disease and represents an abdominal emergency. It includes a variety of conditions, extending from localized diverticular inflammation to fecal peritonitis, hence the importance of an accurate diagnosis. Contrast-enhanced computed tomography (CE-CT) plays a pivotal role in the diagnosis due to its high sensitivity, specificity, accuracy, and interobserver agreement. In fact, CE-CT allows alternative diagnoses to be excluded, the inflamed diverticulum to be localized, and complications to be identified. Imaging findings have been reviewed, dividing them into bowel and extra-intestinal wall findings. Moreover, CE-CT allows staging of the disease; the most used classifications of ACD severity are Hinchey's modified and WSES classifications. Differential diagnoses include colon carcinoma, epiploic appendagitis, ischemic colitis, appendicitis, infectious enterocolitis, and inflammatory bowel disease. We propose a structured reporting template to standardize the terminology and improve communication between specialists involved in patient care.

Optimizing Outpatient Oral Contrast Use in Abdominal CT-A Radiology Pandemic Response Initiative to Reduce Patient Time in the Waiting Room and Reduce Costs, While Improving Patient Experience

Purpose: The aim was to reduce outpatient wait time and improve patient experience by optimising oral contrast use. Methods: Our multidisciplinary stakeholder collaboration implemented two simultaneous interventions: (1) Creation of 'oral contrast policy', limiting recommended indications. (2) Creation of a new shorter oral contrast regime (30 vs 60 min). We conducted a retrospective service evaluation of oral contrast use in outpatient (OP) abdominal CT at baseline and post-intervention. Patient wait times were measured and per-patient cost-savings were reported. An image quality review was performed by 2 blinded abdominal radiologists. Patient experience was evaluated with a standard voluntary survey. Statistical analysis was performed comparing baseline and evaluation outcomes using Chi-square or Fisher Exact test for categorical variables and Student's t-test or ANOVA for continuous data. Results: Over 1-month periods, OP CT scans were assessed in baseline (pre-pandemic) n = 575, baseline (pandemic) n = 495 and post-intervention n = 545 groups. Oral contrast use reduced from 420/575, 73.0% at baseline to 178/545, 32.7% post intervention. The turn-around time reduced by 15.8 minutes per patient from 70.3 to 54.5 minutes, P < .001 (Interventions 1 and 2). The diagnostic quality did not differ between the oral contrast regimes (Intervention 2, P = 1.0, P = .08). No repeat CTs were needed due to lack of oral contrast (Intervention 1) or poor opacification (Intervention 2). There was oral contrast cost reductions of 69.1-78.4% (P < .001). Patients reported their overall experience was improved post-intervention (Interventions 1 and 2). Conclusions: Optimising the CT oral contrast service through judicious use and a shorter regime, reduced patient wait times, improved patient experience and preserved diagnostic quality.

Abdominal Pain in the Emergency Department: How to Select the Correct Imaging for Diagnosis

Abdominal pain is a common presenting complaint in the emergency department, and utilization of diagnostic imaging is often a key tool in determining its etiology. Plain radiography has limited utility in this population. Computed tomography (CT) is the imaging modality of choice for undifferentiated abdominal pain. Ultrasound and magnetic resonance imaging may be helpful in specific scenarios, primarily in pediatrics and pregnancy, and offer the benefit of eliminating ionizing radiation risk of CT. Guidance for imaging selection is determined by location of pain, special patient considerations, and specific suspected etiologies. Expert guidance is offered by the American College of Radiology Appropriateness Criteria^® which outlines imaging options based on location of pain.

The feasibility of deep learning-based synthetic contrast-enhanced CT from nonenhanced CT in emergency department patients with acute abdominal pain

Our objective was to investigate the feasibility of deep learning-based synthetic contrast-enhanced CT (DL-SCE-CT) from nonenhanced CT (NECT) in patients who visited the emergency department (ED) with acute abdominal pain (AAP). We trained an algorithm generating DL-SCE-CT using NECT with paired precontrast/postcontrast images. For clinical application, 353 patients from three institutions who visited the ED with AAP were included. Six reviewers (experienced radiologists, ER1-3; training radiologists, TR1-3) made diagnostic and disposition decisions using NECT alone and then with NECT and DL-SCE-CT together. The radiologists’ confidence in decisions was graded using a 5-point scale. The diagnostic accuracy using DL-SCE-CT improved in three radiologists (50%, P = 0.023, 0.012, < 0.001, especially in 2/3 of TRs). The confidence of diagnosis and disposition improved significantly in five radiologists (83.3%, P < 0.001). Particularly, in subgroups with underlying malignancy and miscellaneous medical conditions (MMCs) and in CT-negative cases, more radiologists reported increased confidence in diagnosis (83.3% [5/6], 100.0% [6/6], and 83.3% [5/6], respectively) and disposition (66.7% [4/6], 83.3% [5/6] and 100% [6/6], respectively). In conclusion, DL-SCE-CT enhances the accuracy and confidence of diagnosis and disposition regarding patients with AAP in the ED, especially for less experienced radiologists, in CT-negative cases, and in certain disease subgroups with underlying malignancy and MMCs.

[Imaging in the acute abdomen-part 2 : Case examples of frequent organ-specific causes: gastrointestinal tract and urogenital system]

The acute abdomen is a potentially life-threatening condition and requires a rapid diagnosis. After clinical inspection and in cases with unclear ultrasound findings or unclear serious symptoms computed tomography (CT) and in pregnant women and children magnetic resonance imaging (MRI) is usually necessary. This second part of "Imaging in the acute abdomen" focuses on frequent organ specific causes of the gastrointestinal tract and the urogenital system.

[Trauma center management]

Every year, more than 20,000 patients with polytrauma are treated in Germany. The term polytrauma refers to simultaneous injury to several body regions that are individually or collectively life-threatening for the patient. However, this assessment is made based on appropriate scoring systems. Adequate treatment of these patients requires not only medical care at the highest level, but also coordination of organizational/logistical processes. The link between preclinical and clinical care is treatment in the shock room, which should be led by a defined, experienced "trauma leader". Treatment algorithms are based on the current S3 guideline Polytrauma/Serious Injury Treatment of the AWMF and the White Paper on Serious Injury Care. Here, recommendations are defined regarding personnel, spatial, logistical and material requirements. Every shock room team should be trained regularly and have theoretical and practical knowledge on the application of shock room algorithms. This can improve the quality of treatment and thus the probability of survival of critically ill patients. In the shock room itself, the focus is on standardized and priority-oriented assessment and stabilization of the patient. Due to the varying quality of care for severely injured patients in Germany, the TraumaNetwork DGU® initiative was implemented by the German Society of Trauma Surgery to improve the treatment of polytrauma patients by defining standards and improving processes and organization in the care of severely injured patients. In Germany, there are currently 615 participating hospitals that are organized in 52 local trauma networks, some of which are cross state borders.

To Fill or Not to Fill? - Value of the Administration of Positive Rectal Contrast for CT Evaluation of Diverticular Disease of the Colon

PURPOSE

 To assess the value of the administration of positive rectal contrast at CT in patients referred for suspected diverticular disease (DD) of the colon.

MATERIALS AND METHODS

 460 patients (253 male, 207 female; median age 62 years; interquartile range 24) with clinical suspicion of DD of the colon were included in this retrospective IRB-approved study. CT was performed with i. v. contrast only (n = 328, group M1), i. v. + positive rectal contrast (n = 82, group M2), neither i. v. nor rectal contrast (n = 32, group S1), or positive rectal contrast only (n = 19, group S2). Two readers in consensus evaluated all CT datasets concerning diagnosis of DD (yes/no) and categorized findings (classification of diverticular disease (CDD)). Sensitivity, specificity, positive (PPV) and negative (NPV) predictive values for the diagnosis of DD were calculated for all groups, using either clinical follow-up (n = 335) or intraoperative findings (n = 125) as the reference standard. In patients undergoing surgery, radiological staging of DD was correlated with the histopathology (weighted Cohen-k).

RESULTS

 224 patients (48.7 %) were diagnosed with DD. The sensitivity, specificity, PPV, and NPV were as follows. Group M1 / M2: 92 %/92 %, 97 %/94 %, 96 %/96 %, 94 %/89 %, respectively; group S1 / S2: 94 %/86 %, 93 %/80 %, 94 %/92 %, 93 %/67 %, respectively. Radiological staging and histopathology correlated substantially in all groups (k = 0.748-0.861).

CONCLUSION

 Abdominal CT had a high sensitivity and specificity for the diagnosis of DD. Disease staging correlated well with the findings at surgery. Additional positive rectal contrast administration did not have a significant advantage and may therefore be omitted in patients with suspected DD.

KEY POINTS

· CT has a high sensitivity and specificity for diagnosis of DD.. · CT staging using the CDD algorithm correlates very well with surgery.. · Positive rectal contrast administration does not improve diagnosis and radiological staging..

CITATION FORMAT

· Meyer S, Schmidbauer M, Wacker FK et al. To Fill or Not to Fill? - Value of the Administration of Positive Rectal Contrast for CT Evaluation of Diverticular Disease of the Colon. Fortschr Röntgenstr 2021; 193: 804 - 812.

Gut wrenching: cases of missed gastrointestinal tumors and their mimics on computed tomography

Computed tomography (CT) of the abdomen and pelvis is one of the most common imaging studies ordered through the emergency department (ED). Because these studies are ordered for the detection of acute abnormalities and due to the relatively low incidence in patients presenting through the ED, gastrointestinal tumors are commonly missed. Moreover, many CT findings of malignant tumors overlap with benign entities, which can present a diagnostic challenge. This review article will describe the common CT findings of gastric, small bowel, colon, and appendiceal cancer as well as some of the common benign gastrointestinal conditions with similar imaging findings.

Diagnostic performance of CT and the use of GI contrast material for detection of hollow viscus injury after penetrating abdominal trauma. Experience from a level 1 Nordic trauma center

BACKGROUND

Use of gastrointestinal (GI) contrast material for computed tomography (CT) diagnosis of hollow viscus injury (HVI) after penetrating abdominal trauma is still controversial.

PURPOSE

To assess the sensitivity of CT and GI contrast material use in detecting HVI after penetrating abdominal trauma.

MATERIAL AND METHODS

Retrospective analysis (2013-2016) of patients with penetrating abdominal trauma. Data from the local trauma registry, medical records, and imaging from PACS were reviewed. CT and surgical findings were compared.

RESULTS

Of 636 patients with penetrating trauma, 177 (163 men, 14 women) had abdominal trauma (mean age 34 years, age range 16-88 years): 155/177 (85%) were imaged with CT on arrival; 128/155 (83%) were stab wounds and 21/155 (14%) were gunshot wounds; 47/155 (30%) had emergent surgery after CT. Two patients were imaged using oral, rectal and i.v. contrast; 23 with rectal and i.v. contrast; and 22 with i.v. contrast only. Surgery revealed HVI in 26 patients. CT had an overall sensitivity 69.2%, specificity 90.5%, PPV 90.0%, and NPV 70.4%. CT with oral and/or rectal contrast (n = 25) had sensitivity 66.7%, specificity 71.4%, PPV 85.7%, and NPV 45.5%. CT with i.v. contrast only (n = 22) had 75% sensitivity, 100% specificity, PPV 100%, and NPV 87.5%. No statistically significant difference was found between sensitivity of CT with GI contrast material and i.v. contrast only (P = 1).

CONCLUSION

Stab wounds were the most common cause of penetrating abdominal trauma. CT had 69.2% sensitivity and 90.5% specificity in detecting HVI. CT with GI contrast had similar sensitivity as CT with i.v. contrast only.

Use of Enteric Contrast Material for Abdominopelvic CT in Penetrating Traumatic Injury in Adults: Comparison of Diagnostic Accuracy Systematic Review and Meta-Analysis

BACKGROUND. Scarce evidence exists on the diagnostic benefit of enteric contrast administration for abdominopelvic CT performed in the setting of penetrating trauma. OBJECTIVE. The purpose of this systematic review and meta-analysis is to compare the diagnostic accuracy of CT using enteric contrast material with that of CT not using enteric contrast material in penetrating traumatic abdominopelvic injury in adults. EVIDENCE ACQUISITION. A protocol was registered a priori (PROSPERO CRD42019139613). MEDLINE and EMBASE databases were searched until June 25, 2019. Studies were included that evaluated the diagnostic accuracy of abdominopelvic CT either with or without enteric (oral and/or rectal) contrast material in patients presenting with penetrating traumatic injury. Relevant study data metrics and risk of bias were assessed. Bivariate random-effects meta-analyses and meta-regression modeling were performed to assess and compare diagnostic accuracies. EVIDENCE SYNTHESIS. From an initial sample of 829 studies, 12 studies were included that reported on 1287 patients with penetrating injury (389 with confirmed bowel, mesenteric, or other abdominopelvic organ injury). The enteric contrast material group (seven studies; 506 patients; 124 patients with confirmed penetrating injury) showed a sensitivity of 83.8% (95% CI, 73.7-90.5%) and specificity of 93.8% (95% CI, 83.6-97.8%). The group without enteric contrast administration (six studies; 781 patients; 265 patients with confirmed penetrating injury) showed a sensitivity of 93.0% (95% CI, 86.8-96.4%) and a specificity of 90.3% (95% CI, 81.4-95.2%). No statistically significant difference was identified for sensitivity (p = .07) or specificity (p = .37) between the groups with and without enteric contrast material according to meta-regression. Nine of 12 studies showed risk of bias in at least one QUADAS-2 domain (most frequently limited reporting of blinding of radiologists or lack of blinding of radiologists, insufficient clinical follow-up for the reference standard, and limited reporting of sampling methods). CONCLUSION. The use of enteric contrast material for CT does not provide a significant diagnostic benefit for penetrating traumatic injury. CLINICAL IMPACT. Eliminating enteric contrast administration for CT in penetrating traumatic injury can prevent delays in imaging and surgery and reduce cost.

ACR Appropriateness Criteria® Left Lower Quadrant Pain-Suspected Diverticulitis

This review summarizes the relevant literature regarding imaging of suspected diverticulitis as an etiology for left lower quadrant pain, and imaging of complications of acute diverticulitis. The most common cause of left lower quadrant pain in adults is acute sigmoid or descending colonic diverticulitis. Appropriate imaging triage for patients with suspected diverticulitis should address the differential diagnostic possibilities and what information is necessary to make a definitive management decision. Patients with diverticulitis may require surgery or interventional radiology procedures because of associated complications, including abscesses, fistulas, obstruction, or perforation. As a result, there has been a trend toward greater use of imaging to confirm the diagnosis of diverticulitis, evaluate the extent of disease, and detect complications before deciding on appropriate treatment. Additionally, in the era of bundled payments and minimizing health care costs, patients with acute diverticulitis are being managed on an outpatient basis and rapid diagnostic imaging at the time of initial symptoms helps to streamline and triage patients to the appropriate treatment pathway. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Adhesive Small Bowel Obstruction: Predictive Radiology to Improve Patient Management

Adhesive small bowel obstruction (SBO) remains one of the leading causes of emergency room visits and is still associated with high morbidity and mortality rates. Because the management of adhesive SBO has shifted from immediate surgery to nonoperative treatment in the absence of ischemia, it is crucial to rapidly detect or predict strangulation, which requires emergent surgery. CT is now established as the best imaging technique for the initial assessment of patients suspected of having adhesive SBO. CT helps confirm the diagnosis of mechanical SBO, locate the site of obstruction, establish the cause, and detect complications. This article is a review of the role of imaging in answering specific questions to help predict the management needs of each individual patient. It includes (a) an update on the best CT signs for predicting ischemia and a need for bowel resection; (b) a discussion of the CT features that help differentiate open-loop from closed-loop obstruction and a single adhesive band from matted adhesions and how these differences can influence the management; and (c) a review of the main CT predictors of the success or failure of nonoperative management in adhesive SBO.

Effect of intravenous contrast for CT abdomen and pelvis on detection of urgent and non-urgent pathology: can repeat CT within 72 hours be avoided?

PURPOSE

To determine if administering IV contrast for CT abdomen and pelvis improves detection of urgent and clinically important non-urgent pathology in patients with urgent clinical symptoms compared to patients not receiving IV contrast, and in turn to determine whether repeat CT exams on the same patient within 72 h were of low diagnostic benefit if the first CT was performed with IV contrast.

METHODS

We evaluated 400 consecutive patients who had CT abdomen and pelvis (CT AP) examinations repeated within 72 h. For each patient, demographic data, reason for examination, examination time stamps, and examination technique were documented. CT AP radiology reports were reviewed and both urgent and non-urgent pathology was extracted.

RESULTS

Of 400 patients, 63% had their initial CT AP without contrast. Administration of IV contrast for the first CT AP was associated with increased detection of urgent findings compared with non-contrast CT (p = 0.004) and a contrast-enhanced CT AP following an initial non-contrast CT AP examination better characterized both urgent (p = 0.002) and non-urgent findings (p < 0.001). Adherence to ACR appropriateness criteria for IV contrast administration was associated with increased detection of urgent pathology on the first CT (p = 0.02), and the second CT was more likely to be performed with IV contrast if recommended by the radiologist reading the first CT (p = 0.0006).

CONCLUSION

In the absence of contraindications, encouraging urgent care physicians to preferentially order IV contrast-enhanced CT AP examinations in adherence with ACR appropriateness criteria may increase detection of urgent pathology and avoid short-term repeat CT AP.

An international survey to assess use of oral and rectal contrast in CT protocols for penetrating torso trauma

PURPOSE

There is controversy regarding the administration of oral and rectal contrast for CT performed to detect bowel injury in the context of penetrating torso trauma. Given the lack of published societal guidelines, our goal was to survey radiologists from the American Society of Emergency Radiology membership database to determine consensus on CT protocols for penetrating trauma.

METHODS

With ethics board approval, an anonymous ten-question online survey was distributed via email to 589 radiologists in the American Society of Emergency Radiology (ASER) member database. The survey was open for a 4-week period in February 2018. A commercially available website that allows subscribers to create and analyze survey results was used for analysis.

RESULTS

We received 124 responses (21% response rate) with a majority from U.S. institutions (82%). Seventy-four percent of respondents indicated they do not routinely administer oral contrast in penetrating trauma, 68% do not administer rectal contrast, and 90% do not use commercially available software to assess penetrating injury trajectory. Results from U.S. and non-U.S. practices were comparable. The decision to administer intraluminal contrast is made by the referring physician at 52% of institutions. There is in-house attending level radiology coverage at 54% of institutions and when asked if trauma scans are reviewed before removing the patient from the table, 41% of respondents answered "No."

CONCLUSION

Enteric contrast is used in a minority of respondents' centers for penetrating trauma cases, which is likely driven by a perceived lack of added benefit and delays in patient care.

An assessment of repeat computed tomography utilization in the emergency department in the setting of blunt trauma

PURPOSE

Computed tomography (CT) is a standard imaging modality utilized during the evaluation of trauma patients in the emergency department (ED). However, while it is common to utilize intravenous (IV) contrast as an adjunct, the use of multiple CT scans and how it impacts patient flow can lead to changes in patient management. Our objectives are to assess length of stay (LOS) and rates of acute kidney injury (AKI), when two CT scans of the abdomen/pelvis are performed compared to one CT scan.

METHODS

Data of trauma hospital encounters were retrospectively collected during a 5-year period at a large, level 1 trauma center. Encounters were categorized into patients who received one or two CT scans of the abdomen/pelvis, as well as if they had received IV contrast or not. CT scan reads were extracted from chart records, and groups were compared.

RESULTS

Of 5787 patient encounters, 5335 (93.4%) received IV contrast and 75 (1.3%) received two CT scans. Lower rates of AKI were associated with IV contrast (2.5 vs 12.5%). Receiving two CT scans was associated with increased rates of AKI (20.0 vs 3.0%; p < 0.0001), ICU admissions (88.0 vs 25.1%; p < 0.0001), and hospital LOS (21.9 vs 1.4 days; p < 0.0001). Of the repeat CT scans, 59.4% demonstrated no significant difference and did not require blood products or the operating room.

CONCLUSION

Two CT scans performed during blunt trauma encounters demonstrated mixed benefit and were associated with an increased hospital LOS. Additionally, IV contrast was associated with lower rates of AKI.

Clinical impact of computed tomography in the emergency department in nontraumatic chest and abdominal conditions

AIM

To evaluate the clinical impact of CT scan in modifying the clinical management in patients referred to the emergency department.

METHODS

We prospectively evaluated 300 patients (177 males, 63 ± 18 years old) admitted in the emergency department (ED) of a single institution, who underwent a CT examination for thoracic and/or abdominal complains. Demographic and clinical data were collected. Hypothesized outcome prior to CT scan and final management (i.e., discharge, short observation in the ED, hospitalization, and department of admission) were compared.

RESULTS

After CT examination, a major variation in diagnosis occurred in 37% of cases and clinical management changed in 43%, occurring in 51% of patients who underwent abdominal CT, in 40% of chest CT, and in 29% of chest/abdominal CT (P = 0.015). Department of hospitalization changed in 26% of cases (P < 0.001). Clinical impact of CT scan was significantly associated (P = 0.001) with the color code at admission. In particular, the more severe was the clinical condition, the lower was the variation of management after CT examination.

CONCLUSIONS

This work confirms the crucial role of CT examination in the management of nontraumatic patients admitted to the ED, both in terms of better clarifying the diagnosis and in influencing the clinical management.

To what extent do hospitalised patients receive appropriate CT and MRI scans? Results of a cross-sectional study in Southern Italy

OBJECTIVES

The aim of this study was to assess the frequency of appropriateness of inpatient CT and MRI scans performed in Southern Italy.

METHODS

The study was carried out by retrospectively reviewing medical records of adult patients admitted between 1 January and 31 December 2012 in two hospitals. The evaluation of appropriateness was performed according to the American College of Radiology Appropriateness Criteria, which assigns a score between 1 and 9.

RESULTS

Eight hundred and fifty-three medical records were reviewed. Six hundred and thirty-nine patients received CT examinations and 256 received MRI examinations. Four hundred and ninety-six (77.6%) of the patient population had appropriate CT and 202 (78.9%) received appropriate MRI examinations. The appropriateness was associated with: a confirmation of the diagnostic hypothesis, only one examination performed during hospital stay, the anatomical scan region, with musculoskeletal system being the least appropriate anatomical scan region. Moreover, for CT examinations, appropriateness was also associated with no use of contrast agent.

CONCLUSIONS

Our findings highlight the need to reduce inappropriate use of CT and MRI. The study showed that the tool used is reliable to measure the extent of appropriateness of diagnostic imaging for inpatient examinations.

Single-Contrast CT for Detecting Bowel Injuries in Penetrating Abdominopelvic Trauma

OBJECTIVE

Many centers advocate use of triple-contrast (IV, oral, and rectal) CT for assessing hemodynamically stable patients with penetrating abdominopelvic trauma. Enteric contrast material has several disadvantages, leading our practice to pursue use of single-contrast (IV) CT. We conducted a retrospective review of electronic medical records at our institution to assess the accuracy of single-contrast CT for diagnosing bowel injuries in cases of penetrating abdominopelvic trauma.

MATERIALS AND METHODS

We retrospectively reviewed patients who presented to our emergency department between January 1, 2004, and March 1, 2014, with penetrating abdominopelvic trauma, underwent an abdominopelvic CT, and had surgery performed thereafter. We reviewed pertinent emergency department records for details regarding the site of injury, the number of injuries per patient, and the type of weapon used. We correlated CT reports with operative notes for presence and sites of bowel injury.

RESULTS

A total of 274 patients (median age, 27 years old) met our inclusion criteria; 77% had sustained gunshot wounds (GSWs). CT showed bowel injury in 173 cases; surgery revealed bowel injury in 162 cases. CT had 142 true-positive, 31 false-positive, 81 true-negative, and 20 false-negative cases, resulting in sensitivity of 88%, specificity of 72%, positive predictive value of 82%, and negative predictive value of 80% for detecting bowel injuries. CT had the highest sensitivity and specificity in patients with multiple GSWs (94% and 79%, respectively) and those with injuries to the stomach and rectum.

CONCLUSION

Single-contrast CT can show bowel injuries in patients with penetrating abdominopelvic trauma with accuracy comparable with that reported for triple-contrast CT.

CT for Acute Nontraumatic Abdominal Pain-Is Oral Contrast Really Required?

RATIONALE AND OBJECTIVES

This study aims to compare the diagnostic performance of abdominal computed tomography (CT) performed with and without oral contrast in patients presenting to the emergency department (ED) with acute nontraumatic abdominal pain.

MATERIALS AND METHODS

Between December 2013 and December 2014, 348 adult patients presenting to the ED of a large tertiary medical center with nontraumatic abdominal pain were evaluated. Exclusion criteria for the study were history of inflammatory bowel disease, recent abdominal operation and suspected renal colic, abdominal aortic aneurysm rupture, or intestinal obstruction. All patients underwent intravenous contrast-enhanced abdominal CT on a Philips Brilliance 64-slice scanner using a routine abdomen protocol. The study group included 174 patients who underwent abdominal CT scanning without oral contrast, recruited using convenience sampling. A control group of 174 patients was matched to the cohort groups' gender and age and underwent abdominal CT with oral contrast material during the same time period. The patients' medical records were reviewed for various clinical findings and for the final clinical diagnosis. The CT exams were initially reviewed by a senior attending radiologist to determine the exams' technical adequacy and to decide whether an additional scan with oral contrast was required. Two senior radiologists, blinded to the clinical diagnosis, later performed consensus reading to determine the contribution of oral contrast administration to the radiologists' diagnostic confidence and its influence on diagnosing various radiological findings.

RESULTS

Each group consisted of 82 men and 92 women. The average age of the two groups was 48 years. The main clinical diagnoses of the pathological examinations were appendicitis (17.5%), diverticulitis (10.9%), and colitis (5.2%). A normal CT examination was found in 34.8% of the patients. There was no significant difference between the groups regarding most of the clinical parameters that were examined. None of the examinations of all of the 174 study group patients was found to be technically inadequate, and therefore no patient had to undergo additional scanning to establish a diagnosis. The consensus reading of the senior radiologists determined that the lack of oral contrast was insignificant in 96.6% of the cases and that contrast material might have been useful in only 6 of 174 study group patients (3.4%). The radiologists found oral contrast to be helpful only in 8 of 174 control group patients (4.6%). There was no significant difference between the clinical and radiological diagnoses in both groups (study group, P = 0.261; control group, P = 0.075).

CONCLUSIONS

Our study shows that oral contrast is noncontributory to radiological diagnosis in most patients presenting to the ED with acute nontraumatic abdominal pain. These patients can therefore undergo abdominal CT scanning without oral contrast, with no effect on radiological diagnostic performance.

Research Priorities in the Utilization and Interpretation of Diagnostic Imaging: Education, Assessment, and Competency

The appropriate selection and accurate interpretation of diagnostic imaging is a crucial skill for emergency practitioners. To date, the majority of the published literature and research on competency assessment comes from the subspecialty of point-of-care ultrasound. A group of radiologists, physicists, and emergency physicians convened at the 2015 Academic Emergency Medicine consensus conference to discuss and prioritize a research agenda related to education, assessment, and competency in ordering and interpreting diagnostic imaging. A set of questions for the continued development of an educational curriculum on diagnostic imaging for trainees and competency assessment using specific assessment methods based on current best practices was delineated. The research priorities were developed through an iterative consensus-driven process using a modified nominal group technique that culminated in an in-person breakout session. The four recommendations are: 1) develop a diagnostic imaging curriculum for emergency medicine (EM) residency training; 2) develop, study, and validate tools to assess competency in diagnostic imaging interpretation; 3) evaluate the role of simulation in education, assessment, and competency measures for diagnostic imaging; 4) study is needed regarding the American College of Radiology Appropriateness Criteria, an evidence-based peer-reviewed resource in determining the use of diagnostic imaging, to maximize its value in EM. In this article, the authors review the supporting reliability and validity evidence and make specific recommendations for future research on the education, competency, and assessment of learning diagnostic imaging.

Is Oral Contrast Necessary for Multidetector Computed Tomography Imaging of Patients with Acute Abdominal Pain?

Purpose

The purpose of our study was to validate the hypothesis that eliminating the use of oral contrast for multidetector computed tomography (MDCT) would not affect the detection of acute abdominal abnormalities in emergency room patients.

Methods

We conducted a retrospective study to assess the effect of discontinuing oral contrast use for MDCT scans of the abdomen and pelvis for patients presenting with acute abdominal pain and body mass index (BMI) >25. Patients with BMI <25 continued to receive oral contrast. The medical records were reviewed to determine the rate of repeat imaging within 7 days from the initial CT scan, as well as delayed or missed diagnoses related to the absence of oral contrast. The study was approved by the research ethics board at our institution.

Results

A total of 1378 patients had an MDCT examination of the abdomen and pelvis between November 1, 2012, and October 31, 2013. 375 patients met the inclusion criteria (174 males and 201 females; mean age 57 years; range 18-97 years). Seven of 375 (1.9%) patients had a repeat CT examination with oral contrast within 7 days. Of these 7 patients, none had a change in the course of their management due to the utilization of oral contrast. No delayed or missed diagnoses related to the absence of oral contrast were identified.

Conclusion

Omitting oral contrast for imaging patients with BMI >25 presenting with acute abdominal pain resulted in no delayed or missed diagnoses, in our retrospective study. The benefits of prompt imaging diagnosis outweigh the unlikely need for repeat imaging.

Evaluation of Posttreatment Follow-Up of Patients With Prostate Cancer Relative to the American College of Radiology's Appropriateness Criteria

OBJECTIVE

The American College of Radiology (ACR) Appropriateness Criteria panel has recommended that patients with prostate cancer who have received treatment undergo imaging only after suspected cancer recurrence. We examined whether local physicians followed this recommendation and what types of imaging examinations were ordered in a cohort of patients with local prostate cancer.

MATERIALS AND METHODS

The Rochester Epidemiology Project, a research consortium that collects, links, and stores medical record information of Olmsted County, Minnesota, residents, was used to capture the complete medical history of treated patients with prostate cancer from 2000 through 2011. Clinical information and imaging examinations performed were retrieved by chart review. Suspected recurrence was defined as treatment-specific prostate-specific antigen level elevations, bone pain, or abnormal digital rectal examination findings.

RESULTS

Of the 670 treated patients with prostate cancer who were included in the final analysis, 129 (19%) underwent posttreatment imaging. After excluding imaging related to retreatment or another cancer, 13 patients (i.e., 2% of the entire cohort and 10% of imaged patients) underwent imaging in the absence of suspected recurrence. A total of 90 patients (70% of imaged patients) underwent imaging after suspected recurrence. Of these 90 patients, 62 (69%) underwent a bone scan as their first imaging modality either alone or in combination with other imaging modalities. Of the providers who ordered a bone scan first, 27% were urologists, 23% were radiation oncologists, and 24% were primary care physicians.

CONCLUSION

Most patients in this study did not undergo imaging in the absence of suspected recurrence. Various types of imaging examinations were ordered for patients with suspected recurrence.

Laparoscopic peritoneal lavage or sigmoidectomy for perforated diverticulitis with purulent peritonitis: a multicentre, parallel-group, randomised, open-label trial

BACKGROUND

Case series suggest that laparoscopic peritoneal lavage might be a promising alternative to sigmoidectomy in patients with perforated diverticulitis. We aimed to assess the superiority of laparoscopic lavage compared with sigmoidectomy in patients with purulent perforated diverticulitis, with respect to overall long-term morbidity and mortality.

METHODS

We did a multicentre, parallel-group, randomised, open-label trial in 34 teaching hospitals and eight academic hospitals in Belgium, Italy, and the Netherlands (the Ladies trial). The Ladies trial is split into two groups: the LOLA group comparing laparoscopic lavage with sigmoidectomy and the DIVA group comparing Hartmann's procedure with sigmoidectomy plus primary anastomosis. The DIVA section of this trial is still underway but here we report the results of the LOLA section. Patients with purulent perforated diverticulitis were enrolled for LOLA, excluding patients with faecal peritonitis, aged older than 85 years, with high-dose steroid use (≥20 mg daily), and haemodynamic instability. Patients were randomly assigned (2:1:1; stratified by age [<60 years vs ≥60 years]) using secure online computer randomisation to laparoscopic lavage, Hartmann's procedure, or primary anastomosis in a parallel design after diagnostic laparoscopy. Patients were analysed according to a modified intention-to-treat principle and were followed up after the index operation at least once in the outpatient setting and after sigmoidoscopy and stoma reversal, according to local protocols. The primary endpoint was a composite endpoint of major morbidity and mortality within 12 months. This trial is registered with ClinicalTrials.gov, number NCT01317485.

FINDINGS

Between July 1, 2010, and Feb 22, 2013, 90 patients were randomly assigned in the LOLA section of the Ladies trial when the study was terminated by the data and safety monitoring board because of an increased event rate in the lavage group. Two patients were excluded for protocol violations. The primary endpoint occurred in 30 (67%) of 45 patients in the lavage group and 25 (60%) of 42 patients in the sigmoidectomy group (odds ratio 1·28, 95% CI 0·54-3·03, p=0·58). By 12 months, four patients had died after lavage and six patients had died after sigmoidectomy (p=0·43).

INTERPRETATION

Laparoscopic lavage is not superior to sigmoidectomy for the treatment of purulent perforated diverticulitis.

FUNDING

Netherlands Organisation for Health Research and Development.