ACR Appropriateness Criteria® Left Lower Quadrant Pain-Suspected Diverticulitis

Quality improvement project aiming to reduce inappropriate use of AXRs in the ED

BACKGROUND

There is compelling evidence that AXRs have limited clinical value in the acute setting. Despite this, they are frequently used in many EDs. This quality improvement project (QIP) aimed to reduce unnecessary AXR use in a single-centre ED.

METHOD

All consecutive AXRs conducted on patients aged 16 years and above in a District General Hospital ED in England between 2 August 2021 and 5 June 2022 were included. This period of time was divided into a pre-intervention and intervention period, during which iterative plan-do-study-act cycles were undertaken to implement a wide range of educational and system level interventions.

RESULTS

501 AXRs were performed during the QIP. The average number of AXRs per fortnight fell from 27.5 during the preintervention period to 17.6 during the intervention period and met criteria for special cause variation. No special cause variation in CT usage was observed, with an average number of 70.7 and 74 CT abdomen-pelvis scans during the preintervention and intervention periods, respectively. 119 (23.8%) AXRs showed acute and clinically significant findings, and of this group 118/119 (99.2%) underwent further imaging. In contrast, 382 (76.2%) AXRs had no acute or clinically significant findings, and of this group 344/382 (90.1%) proceeded to further imaging.

CONCLUSION

In this single-centre QIP, coordinated multidisciplinary interventions were effective in reducing unnecessary AXR usage without resulting in excess CTs. The methods and interventions described are easily reproducible at minimal expense and may be of interest to other departments undertaking quality improvement work in this area.

Canadian Association of Radiologists Gastrointestinal Imaging Referral Guideline

The Canadian Association of Radiologists (CAR) Gastrointestinal Expert Panel consists of radiologists, a gastroenterologist, a general surgeon, a family physician, a patient advisor, and an epidemiologist/guideline methodologist. After developing a list of 20 clinical/diagnostic scenarios, a systematic rapid scoping review was undertaken to identify systematically produced referral guidelines that provide recommendations for one or more of these clinical/diagnostic scenarios. Recommendations from 58 guidelines and contextualization criteria in the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) for guidelines framework were used to develop 85 recommendation statements specific to the adult population across the 20 scenarios. This guideline presents the methods of development and the referral recommendations for dysphagia/dyspepsia, acute nonlocalized abdominal pain, chronic abdominal pain, inflammatory bowel disease, acute gastrointestinal bleeding, chronic gastrointestinal bleeding/anemia, abnormal liver biopsy, pancreatitis, anorectal diseases, diarrhea, fecal incontinence, and foreign body ingestion.

Management of Diverticulitis: A Review

Importance

Care of patients with diverticulitis is undergoing a paradigm shift. This narrative review summarizes the current evidence for left-sided uncomplicated and complicated diverticulitis. The latest pathophysiology, advances in diagnosis, and prevention strategies are also reviewed.

Observations

Treatment is moving to the outpatient setting, physicians are forgoing antibiotics for uncomplicated disease, and the decision for elective surgery for diverticulitis has become preference sensitive. Furthermore, the most current data guiding surgical management of diverticulitis include the adoption of new minimally invasive and robot-assisted techniques.

Conclusions and Relevance

This review provides an updated summary of the best practices in the management of diverticulitis to guide colorectal and general surgeons in their treatment of patients with this common disease.

Performance of Ultrasonography in the Diagnosis of Acute Colonic Diverticulitis

OBJECTIVES

Computed tomography is regarded as the reference-standard imaging modality for the assessment of acute left-sided colonic diverticulitis (ALCD). However, its utility may be impaired by cost issues, limited availability, radiation exposure, and contrast-related adverse effects. Ultrasonography is increasingly advocated as an alternative technique for evaluating ALCD, although there is variation regarding its accuracy in disease diagnosis and staging and in determining alternative diagnoses. The aim of this study was to assess the performance of ultrasonography in diagnosing ALCD, differentiating complicated from non-complicated disease and defining alternative diseases related to left lower quadrant pain.

METHODS

Within a 2-year period, all consecutive adult patients with clinically suspected ALCD and available abdominal computed tomography were prospectively evaluated and planned to undergo an abdominal ultrasonographic examination, tailored to the assessment of left lower quadrant. Computed tomography (CT) was regarded as the reference standard.

RESULTS

A total of 132 patients (60 males, 72 females; mean age: 61.3 ± 11 years) were included. The sensitivity, specificity, and area under curve of ultrasonography for diagnosing ALCD were 88.6, 84.9, and 86.8%, with positive and negative predictive values of 89.7 and 83.3%, respectively. The method had sensitivity, specificity, and area under curve of 77.8, 100, and 88.9%, respectively, for defining complicated disease. The area under the curve for the identification of alternative diseases in patients with left lower quadrant pain was 90.9%.

CONCLUSIONS

Ultrasonography has high diagnostic accuracy for diagnosing ALCD, differentiating complicated from non-complicated disease and establishing alternative diagnoses related to left lower quadrant pain. A low threshold to get a CT should be maintained as not to miss cases that may mimic ALCD.

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.

ChatGPT-4 Assistance in Optimizing Emergency Department Radiology Referrals and Imaging Selection

PURPOSE

The quality of radiology referrals influences patient management and imaging interpretation by radiologists. The aim of this study was to evaluate ChatGPT-4 as a decision support tool for selecting imaging examinations and generating radiology referrals in the emergency department (ED).

METHODS

Five consecutive clinical notes from the ED were retrospectively extracted, for each of the following pathologies: pulmonary embolism, obstructing kidney stones, acute appendicitis, diverticulitis, small bowel obstruction, acute cholecystitis, acute hip fracture, and testicular torsion. A total of 40 cases were included. These notes were entered into ChatGPT-4, requesting recommendations on the most appropriate imaging examinations and protocols. The chatbot was also asked to generate radiology referrals. Two independent radiologists graded the referral on a scale ranging from 1 to 5 for clarity, clinical relevance, and differential diagnosis. The chatbot's imaging recommendations were compared with the ACR Appropriateness Criteria (AC) and with the examinations performed in the ED. Agreement between readers was assessed using linear weighted Cohen's κ coefficient.

RESULTS

ChatGPT-4's imaging recommendations aligned with the ACR AC and ED examinations in all cases. Protocol discrepancies between ChatGPT and the ACR AC were observed in two cases (5%). ChatGPT-4-generated referrals received mean scores of 4.6 and 4.8 for clarity, 4.5 and 4.4 for clinical relevance, and 4.9 from both reviewers for differential diagnosis. Agreement between readers was moderate for clinical relevance and clarity and substantial for differential diagnosis grading.

CONCLUSIONS

ChatGPT-4 has shown potential in aiding imaging study selection for select clinical cases. As a complementary tool, large language models may improve radiology referral quality. Radiologists should stay informed about this technology and be mindful of potential challenges and risks.

Acute Diverticulitis in Young Patients: A Review of the Changing Epidemiology and Etiology

Acute diverticulitis is one of the leading gastrointestinal causes for hospitalization. The incidence of acute diverticulitis has been increasing in recent years, especially in patients under 50 years old. Historically, acute diverticulitis in younger patients was felt to represent a separate entity, being more virulent and associated with a higher rate of recurrence. Accordingly, young patients were often managed differently to older counterparts. Our understanding of the natural history of this condition has evolved, and current clinical practice guidelines suggest age should not alter management. The purpose of this review is to evaluate the changing epidemiology of acute diverticulitis, consider potential explanations for the observed increased incidence in younger patients, as well as review the natural history of acute diverticulitis in the younger population.

Magnetic Resonance Imaging for the diagnosis and management of acute colonic diverticulitis: a review of current and future use

Diverticular disease is one of the most common causes of outpatient visits and hospitalisations across Australia, North America and Europe. According to the Gastroenterological Society of Australia (GESA, 2010), approximately 33% of Australians over 45 years of age and 66% over 85 years of age have some form of colonic diverticulosis. Patients with colonic diverticulosis are known to develop subsequent complications such as acute colonic diverticulitis (ACD), and when more than one attack of diverticulitis occurs, there is a 70-90% chance that the individual will experience ongoing problems and recurring infections throughout their lifetime. Medical imaging is fundamental in the diagnosis, treatment and ongoing management of ACD and its complications, with Computed Tomography (CT) identified as the prevailing gold standard in the last few decades. Cross-database searching highlighted a large gap in the literature regarding the effectiveness of Magnetic Resonance Imaging (MRI) as a non-ionising radiation alternative imaging tool for ACD imaging after the mid-2000s, despite ongoing technological advancements in this modality. This narrative review identified 13 key publications (11 primary prospective cohort studies, 1 systematic review and 1 meta-analysis) that evaluate MRI for ACD imaging, of which five were published within the last decade. Several existing MRI protocols are deemed suitable for ACD imaging, and it is recommended they be re-evaluated in larger cohorts. Future studies should consider the rapidly growing technological improvements of MRI, its cost efficiency and its applicability in modern day healthcare settings when addressing ACD management. This is especially important considering the gradual rise in radiation dose among the Australian population attributable to increased CT referrals, alongside increased reporting of ACD cases in younger individuals.

Ultrasound can differentiate complicated and noncomplicated acute colonic diverticulitis: a prospective comparative study with computed tomography

OBJECTIVE

To prospectively assess the diagnostic value of intestinal ultrasound (US) compared to computerized tomography (CT) in differentiating uncomplicated and complicated acute colonic diverticulitis (ACD).

MATERIALS AND METHODS

During a period of 14 months patients referred to the department of Radiology with clinical suspicion of ACD underwent an US examination. All confirmed US ACD diagnosis were included and subsequently underwent an emergency abdominal CT, used as gold standard. The WSES (World Society for Emergent Surgery) classification of diverticulitis was used. Diverticulitis was prospectively classified as either uncomplicated or complicated. Sensitivity, specificity, positive predictive value, and negative predictive values of US were evaluated. Before CT scan, the radiologist indicated whether they would have required or not a complementary CT scan, based on US findings.

RESULTS

Of the 240 patients included in our study, 71 (29.6%) were Stage 0, 127 (53%) Stage 1A, and 42 (17.5%) were moderate-severe ACD (stages 1B, 2A, 2B, 3 and 4). The sensitivity of US for diagnosing complicated ACD was 84% and specificity of 95.8%. Most patients (24 of 27) misclassified by US as uncomplicated diverticulitis were classified on CT as stage 1A. From the 148 cases in which the radiologist considered CT unnecessary, only 3 of these revealed signs of complicated ACD on CT; none of them required emergency surgery.

CONCLUSION

US is an effective technique to differentiate complicated from uncomplicated ACD. Our results suggest that US, may be a valuable alternative to CT for the initial radiologic evaluation in patients with clinical suspicion of ACD.

[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.

Accuracy of preoperative CT staging of acute colonic diverticulitis using the classification of diverticular disease (CDD) - Is there a beneficial impact of water enema and visceral obesity?

PURPOSE

We evaluated the accuracy of preoperative CT in staging colonic diverticulitis (ACD) by using the classification of diverticular disease (CDD) and investigated the diagnostic impact of water enema (WE) and visceral obesity.

METHODS

In this retrospective study, the radiological and hospital information system was searched for patients who underwent CT for clinically suspected ACD prior to surgery between 2009 and 2019. From the initial population (n = 164), we included 155 patients (94.5 %) (85 women; mean age: 58 ± 13 years) matching the following inclusion criteria: i.) clinically suspected ACD, ii.) i.v. contrast-enhanced CT, iii.) surgery for ACD within 1 week after CT, iv.) histopathological report that proved ACD. The remaining 9 patients (5.5 %) were excluded because histopathological reports were lacking (n = 3) or CT was performed without intravenous contrast agent (n = 6). WE (+ butylscopolamine i.v.) was performed in 93 patients (group A, 60 %). 62 patients (group B, 40 %) had no WE. Visceral-to-subcutaneous fat ratio (V/S) was determined for each patient. Two radiologists blinded for final diagnosis independently staged ACD according to CDD and assessed prevalence and confidence ratings of ACD-related CT-findings: pericolonic fat stranding, covered- and free-perforation, local and generalized peritonitis, abscess. Interobserver-agreement of CT-findings were assessed and effects of WE and V/S ratio on the diagnostic accuracy of CT with surgical and histopathological findings as reference were determined by calculating a logistic regression model.

RESULTS

CT-staging showed high accuracy (94 %) and excellent interrater-correlation (ICC 0.96) for staging ACD. WE had no positive impact neither on diagnostic accuracy of staging, nor on confidence ratings of ACD-related CT-findings (all p > 0.5). Confidence ratings were significantly higher in examinations without WE for perforation, peritonitis as well as abscesses (all p < 0.5). Confidence ratings for the assessment of local peritonitis improved significantly with higher V/S (p = 0.049). The increase of V/S significantly correlated with the probability for correct CDD staging of ACD in CT (p = 0.023).

CONCLUSION

Increase of visceral obesity significantly improves accuracy of CT in preoperative staging acute colonic diverticulitis. However, independently of the degree of visceral obesity, water enema has no diagnostic benefit and may therefore be omitted. Overall, CT proves high accuracy in preoperative staging ACD using the classification of diverticular disease.

LEVEL OF EVIDENCE

Retrospective study, observational study.

Influence of clinical suspicion on CT accuracy of acute mesenteric ischemia: Retrospective study of 362 patients

PURPOSE

Acute mesenteric ischemia (AMI) may be underdiagnosed when not clinically suspected before CT is performed. We assessed the influence of a clinical suspicion of AMI on the CT accuracy.

METHOD

This retrospective single-centre study included patients who underwent CT in 2014-2019 and had clinically suspected AMI and/or confirmed AMI. CT protocols were adapted based on each patient's presentation and on findings from unenhanced images. The CT protocol was considered optimal for AMI when it included arterial and portal venous phases. CT protocols, accuracy of reports, and outcomes were compared between the groups with and without suspected AMI before CT.

RESULTS

Of the 375 events, 337 (90 %) were suspected AMI and 66 (18 %) were AMI, including 28 (42 %) with and 38 without suspected AMI. These two groups did not differ significantly regarding the medical history, clinical presentation, or laboratory tests. The CT protocol was more often optimal for AMI in the group with suspected AMI (26/28 [93 %] vs. 28/38 [74 %], p = 0.046). Diagnostic accuracy was not different between groups with and without suspected AMI (26/28 [93 %] vs. 34/38 [90 %], p = 1.00). However, it was lower in the group without suspicion of AMI when the CT protocol was not optimal for AMI (27/28 [96 %] vs 7/10 [70 %], p = 0.048).

CONCLUSIONS

The negative influence of not clinically suspecting AMI can be mitigated by using a tailored CT protocol.

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.

Impact of the COVID-19 pandemic on emergency department CT for suspected diverticulitis

PURPOSE

This study examined the impact of the COVID-19 pandemic on emergency department CT use for acute nontraumatic abdominal pain, to better understand why imaging volume so drastically decreased during the COVID-19 pandemic.

METHODS

This was a retrospective review of emergency imaging volumes from January 5 to May 30, 2020. Weekly volume data were collected for total imaging studies, abdominopelvic CT, and abdominopelvic CTs positive for common causes of acute nontraumatic abdominal pain. Two emergency radiology attendings scored all diverticulitis cases independently, and weekly volume data for uncomplicated and complicated diverticulitis cases was also collected. Volume data prior to and during the COVID-19 pandemic was compared, using 2019 volumes as a control.

RESULTS

During the COVID-19 pandemic, overall emergency imaging volume decreased 30% compared to 2019 (p = 0.002). While the number of emergency abdominopelvic CTs positive for appendicitis and small bowel obstruction did not significantly change during the COVID-19 pandemic, the number of cases of diverticulitis decreased significantly compared to 2019 (p = 0.001). This reduction can be specifically attributed to decreased uncomplicated diverticulitis cases, as the number of uncomplicated diverticulitis cases dropped significantly (p = 0.002) while there was no significant difference in the number of complicated diverticulitis cases (p = 0.09).

CONCLUSIONS

Reduced emergency abdominopelvic CT volume during the COVID-19 pandemic can partially be explained by decreased imaging of lower acuity patients. This data may help formulate future strategies for imaging resource utilization with an improved understanding of the relationship between perceived imaging risk and symptom acuity.

Advanced Fusion Imaging and Contrast-Enhanced Imaging (CT/MRI-CEUS) in Oncology

Fusion imaging depicts an innovative technique that facilitates combining assets and reducing restrictions of advanced ultrasound and cross-sectional imaging. The purpose of the present retrospective study was to evaluate the role of fusion imaging for assessing hepatic and renal lesions. Between 02/2011-08/2020, 92 patients in total were included in the study, of which 32 patients had hepatic lesions, 60 patients had renal lesions. Fusion imaging was technically successful in all patients. No adverse side effects upon intravenous (i.v.) application of SonoVue® (Bracco, Milan, Italy) were registered. Fusion imaging could clarify all 11 (100%) initially as indeterminate described hepatic lesions by computed tomography/magnetic resonance imaging (CT/MRI). Moreover, 5/14 (36%) initially suspicious hepatic lesions could be validated by fusion imaging, whereas in 8/14 (57%), malignant morphology was disproved. Moreover, fusion imaging allowed for the clarification of 29/30 (97%) renal lesions initially characterized as suspicious by CT/MRI, of which 19/30 (63%) underwent renal surgery, histopathology revealed malignancy in 16/19 (84%), and benignity in 3/19 (16%). Indeterminate findings could be elucidated by fusion imaging in 20/20 (100%) renal lesions. Its accessibility and repeatability, even during pregnancy and in childhood, its cost-effectiveness, and its excellent safety profile, make fusion imaging a promising instrument for the thorough evaluation of hepatic and renal lesions in the future.

A Prospective Evaluation of Point-of-Care Ultrasonographic Diagnosis of Diverticulitis in the Emergency Department

STUDY OBJECTIVE

We evaluate the sensitivity and specificity of point-of-care ultrasonography, performed by ultrasonographic fellowship-trained emergency physicians and physician assistants, compared with computed tomography (CT) scan in diagnosing acute diverticulitis in the emergency department (ED).

METHODS

This was a prospective observational study of a convenience sample of patients with suspected diverticulitis who were treated at an academic ED between 2017 and 2020. Sonographers were blinded to clinical data, laboratory results, and CT scan findings. A total of 19 ultrasonographic fellowship-trained emergency physicians and physician assistants performed the ultrasonographic examinations. Point-of-care ultrasonographic diagnosis of acute diverticulitis was defined as the presence of bowel wall thickening, greater than 5 mm, surrounding a diverticulum, enhancement of the surrounding pericolonic fat, and sonographic tenderness to palpation. The primary outcome measures were sensitivity, specificity, positive predictive value, and negative predictive value of point-of-care ultrasonography in the diagnosis of diverticulitis compared with CT, which was considered the criterion standard.

RESULTS

Data from 452 patients were analyzed. Median age was 60 years, 54% were women, and 36% had a diagnosis of diverticulitis based on CT scan. Of the 452 patients, there were 13 false-positive (3%) and 10 false-negative (2%) point-of-care ultrasonographic examinations. Overall, compared with CT, point-of-care ultrasonography had a sensitivity of 92% (95% confidence interval 88% to 96%), specificity of 97% (95% confidence interval 94% to 99%), positive predictive value of 94% (95% confidence interval 90% to 97%), and negative predictive value of 96% (93% to 98%) in the diagnosis of diverticulitis.

CONCLUSION

In a convenience sample of ED patients with suspected diverticulitis, point-of-care ultrasonography performed by ultrasonographic fellowship-trained emergency physicians and physician assistants could be used as an imaging modality for diagnosing acute diverticulitis, with high sensitivity and specificity compared with CT scan.

[Sudden chest pain and lower abdominal pain : The usual suspects]

CLINICAL PROBLEM

Sudden chest pain and sudden abdominal pain are among the most common reasons that lead patients to the emergency room. The heterogeneous field of possible, sometimes serious diagnoses requires a structured and rapid interdisciplinary clarification in order to be able to promptly provide patients with an adequate therapy.

STANDARD RADIOLOGICAL PROCEDURES

Knowing the "usual suspects" of sudden chest and abdominal pain enables the radiologist to quickly select the appropriate imaging method that allows a diagnosis to be made without delay. In addition to pain localization and character, age, gender, any previous illnesses and laboratory results are taken into account in the differential diagnosis.

METHODICAL INNOVATION AND EVALUATION

The technical state of computer tomography (CT) now ensures that most diagnoses can be clarified due to its excellent spatial and temporal resolution. In the abdomen, however, ultrasound should continue to be used at least for primary evaluation. Only if there is a further need for abdominal imaging afterwards is CT indicated for clarification. Magnetic resonance imaging is rarely used in the emergency setting of abdominal pain except to avoid radiation exposure in children or pregnant women.

RECOMMENDATION FOR THE PRACTICE

Knowledge of the usual diagnoses that cause sudden chest or abdominal pain, as well as knowledge of the appropriate examination procedures and classic radiological signs are essential to avoid errors and delays in the emergency diagnosis of sudden chest and abdominal pain.