Initial Imaging Strategy Research Articles

Cost-Effectiveness of Weight-Bearing Computed Tomography in Diagnosing Syndesmotic Instability

Category:Ankle; Sports; OtherIntroduction/Purpose:To optimize clinical outcomes, accurate diagnosis and treatment of syndesmotic instability is critical, but subtle instability can be challenging to identify. Weightbearing computed tomography (WBCT) has proved to be a reliable tool for diagnosing syndesmotic instability under physiologic load. We aimed to examine the cost-effectiveness of WBCT with radiographs and/or conventional CT for the diagnosis of syndesmotic instability from a patient perspective.Methods:A decision tree model was constructed to examine the cost-effectiveness of WBCT versus conventional CT (NWB CT) versus weightbearing (WB) radiographs versus non-weightbearing (NWB) radiographs (base case) as initial imaging with additional possible imaging for1268 patients with suspected syndesmotic instability. Patient's clinical and radiological notes were evaluated until the diagnosis of syndesmotic instability was established. The decision tree's probabilities, durations, and image counts were based on patient data. The main outcomes were 1) total imaging costs needed before syndesmotic instability was diagnosed, 2) quality-adjusted life-years (QALYs), 3) incremental cost-effectiveness ratios (ICERs), and 4) overall radiation dose prior to diagnosis. Imaging costs and radiation dose were derived from National Medicare reimbursement rates and the American College of Radiology, respectively. An incremental cost-effectiveness ratio threshold of $50,000 per quality-adjusted life years was used to evaluate cost-effectiveness. In addition, one-way and two-way sensitivity analyses were performed to determine the robustness of our findings.Results:WBCT resulted in 0.057 additional QALY gained per week compared with NWB radiographs, indicating WBCT to be more effective than NWB radiographs. Costs for WBCT imaging were $38.71 higher than NWB radiographs for an ICER of $38,563.96/QALY. Applying a commonly used threshold of $50,000 per QALY, the patient's willingness-to-pay for the amount of quality-adjusted life-year gained from using WBCT as an initial imaging modality was $54.41, suggesting WBCT first imaging strategy was a cost-effective intervention. In our study, the cost of WBCT imaging was $157.35. Sensitivity analyses demonstrated that WBCT was more cost effective than NWB radiographs up to a cost of $173.05. Additionally, initial WBCT resulted in lower overall radiation dosage (6.4 uSv) compared to the use of the other three imaging modalities as initial imaging strategy (initial NWB radiographs - 12.41 uSv; initial WB radiographs - 8.30 uSv, NWB CT first - 25 uSv).Conclusion:WBCT leads to higher QALYs compared to other diagnostic imaging modalities, resulting in improved outcomes for patients by eliminating redundant imaging.

Ultrasound for the Diagnosis of Biliary Atresia: From Conventional Ultrasound to Artificial Intelligence.

Biliary atresia is an aggressive liver disease of infancy and can cause death without timely surgical intervention. Early diagnosis of biliary atresia is critical to the recovery of bile drainage and long-term transplant-free survival. Ultrasound is recommended as the initial imaging strategy for the diagnosis of biliary atresia. Numerous ultrasound features have been proved helpful for the diagnosis of biliary atresia. In recent years, with the help of new technologies such as elastography ultrasound, contrast-enhanced ultrasound and artificial intelligence, the diagnostic performance of ultrasound has been significantly improved. In this review, various ultrasound features in the diagnosis of biliary atresia are summarized. A diagnostic decision flow chart for biliary atresia is proposed on the basis of the hybrid technologies, combining conventional ultrasound, elastography and contrast-enhanced ultrasound. In addition, the application of artificial intelligence in the diagnosis of biliary atresia with ultrasound images is also introduced.

Cost-Effectiveness Study of Initial Imaging Selection in Acute Ischemic Stroke Care.

National guidelines recommend prompt identification of candidates for acute ischemic stroke (AIS) treatment, requiring timely neuroimaging with CT and/or MRI. CT is often preferred because of its widespread availability and rapid acquisition. Despite higher diagnostic accuracy of MRI, it commonly involves complex workflows that could potentially cause treatment time delays. The purpose of this study was to analyze the impact on outcomes of imaging utilization before treatment decisions at comprehensive stroke centers for patients presenting with suspected AIS in the anterior circulation with last-known-well-to-arrival time 0 to 24 hours. A decision simulation model based on the American Heart Association's recommendations for AIS care pathways was developed from a health care perspective to compare initial imaging strategies: (1) stepwise-CT: noncontrast CT (NCCT) at the time of presentation, with CT angiography (CTA) ± CT perfusion (CTP) only in select patients (initial imaging to exclude hemorrhage and extensive ischemia) for mechanical thrombectomy (MT) evaluation; (2) stepwise-hybrid: NCCT at the time of presentation, with MR angiography (MRA) ± MR perfusion (MRP) only for MT evaluation; (3) stepwise-advanced: NCCT+ CTA at presentation, with MR diffusion-weighted imaging(MR DWI) + MRP only for MT evaluation; (4) comprehensive-CT: NCCT+ CTA+ CTP at the time of presentation; and (5) comprehensive-MR: MR DWI+ MRA+ MRP at the time of presentation. Model parameters were defined using evidence-based data. Cost-effectiveness and sensitivity analyses were performed. The cost-effectiveness analyses revealed that comprehensive-CT and comprehensive-MR yield the highest lifetime quality-adjusted life-years (QALYs) (4.81 and 4.82, respectively). However, the incremental cost-effectiveness ratio of comprehensive-MR is $233,000/QALY compared with comprehensive-CT. Stepwise-CT, stepwise-hybrid, and stepwise-advanced strategies are dominated, yielding lower QALYs and higher costs compared with comprehensive-CT. Performing comprehensive-CT at presentation is the most cost-effective initial imaging strategy at comprehensive stroke centers.

A clinical pathway to minimize computed tomography for suspected nephrolithiasis in children

Ultrasound (US) imaging is preferred in the initial evaluation for children with suspected nephrolithiasis; however, computed tomography (CT) continues to be used in this setting with resultant unnecessary ionizing radiation exposure. The study institution implemented a standardized clinical pathway to reduce rates of CT utilization for children with nephrolithiasis. The aim of this study was to evaluate the impact of this pathway on initial imaging strategies for children with suspected nephrolithiasis. A standardized pathway was designed and implemented using a systematic quality improvement process. A suspected cohort was created using 'reason for study'search terms consistent with a nephrolithiasis diagnosis. A confirmed cohort of children with a final diagnosis of nephrolithiasis was derived from this suspected cohort. The primary outcome was CT use as the initial imaging study in children with suspected or confirmed nephrolithiasis presenting to the emergency department (ED) between October 2013 and February 2018. Comparisons were made before and after pathway implementation (October 2015). Secondary outcomes included rates of CT scan within 30 days, while balancing measures included rates of admission, ED length of stay, and return visits. A total of 534 children with suspected (220 prepathway; 314 postpathway) and 90 children with confirmed (37 prepathway; 53 postpathway) nephrolithiasis were included. For the suspected cohort, CT scans performed as the initial imaging evaluation (9.2% vs 2.5%, P=0.001) and at any time during the index visit (15.7% vs 5.7%, P=0.001) decreased after pathway implementation. Within the confirmed cohort, a non-significant decrease in initial CT rates was observed after implementation. No differences were observed in admission rates or ED length of stay after implementation. A trend towardlower return visits to the ED was seen after pathway implementation (5.5% vs 2.2%, P=0.058). Within a tertiary care pediatric ED associated with a strong institutional experience with clinical pathways, initial CT rates were decreased after pathway implementation for children with suspected nephrolithiasis. While retrospective assessment of suspected disease is limited, this is one of the first studies to address imaging patterns for nephrolithiasis beyond the final discharge diagnosis, thus capturing a broader cohort of children. Children with suspected nephrolithiasis can be safely managed with an US-first approach, and postvisit CT scans are rarely necessary for management. A standardized clinical pathway for suspected nephrolithiasis can reduce rates of initial and overall CT utilization without adversely impacting downstream care.

To image or not in noncyclic breast pain? A systematic review.

Investigation of noncyclic mastalgia in women without signs or risk factors for cancer is controversial. An initial imaging strategy can diagnose breast cancer early, potentially leading to better treatment and survival. However, cancer diagnosis is very uncommon in these cases, and this approach can be harmful, as false positives or suspicion results will lead to unneeded interventions and follow-up. The purpose of this review is to analyse the trade-offs between desirable and undesirable consequences of initial imaging tests against clinical follow-up. We found seven relevant studies, all observational, with some methodological limitations and very low-quality evidence. They showed low breast cancer prevalence (around 1-2%, increasing with age), high sensitivity to rule out disease but moderate specificity to rule it in using mammography and echography, and lacked evidence on follow-up and final outcomes. There is a low prevalence of breast cancer in patients with painful breast with negative physical examination, and very little research to inform about the effect of performing or avoiding initial imaging test on outcomes of interest. With such limited evidence, only a weak recommendation to reinforce shared decision making about what should be done in the primary care setting can be made, with the backup of a specialized breast unit.

Abstract W MP15: Use of Multimodal Imaging for Thrombolysis-Eligible Stroke Patients Presenting to Hospitals in a Large Urban Region

Introduction: Advances in diagnostic imaging of stroke include the use of multimodal techniques, including noninvasive angiography to evaluate the intracranial and cervical vasculature as well as perfusion imaging. Despite increased adoption of these imaging techniques in academic medical centers, the current practice of multimodal imaging utilization among stroke patients in the community has remained largely uncharacterized. Methods: We quantified neuroimaging utilization in the ED among 1700 hyperacute stroke patients participating in the NIH Field Administration of Stroke Therapy Magnesium (FAST-MAG) study throughout Los Angeles and Orange Counties. Subjects were enrolled in the field <2 hours from symptom onset and transported to their usual care hospital, one of 58 centers throughout a single urban region. There was no recommendation as to what type of imaging should be utilized. Results: Of 1700 cases 1699 were imaged a median (IQR) of 92 (74-120) minutes after last known well time and 28 (19-40.75) minutes after ED arrival. The mean age was 71 (SD13) years old and the final diagnosis was cerebral ischemia in 73%, intracerebral hemorrhage in 23%, and mimic in 4%. Initial imaging scanner used in the ED was CT in a preponderance of cases (N=1612, 95%), with MRI in 88 cases (5%). Parenchymal CT scan was almost always performed without contrast and most commonly as the only study. However, CT angiography was obtained in 192 (11%) and perfusion CT in 91 (5.4%) cases in the first 24 hours. MRI imaging was universally obtained using diffusion-weighted images, 60% with MR angiography and 33% included perfusion imaging. Rates of multimodal (CTA and/or CTP) CT imaging utilization increased in the later years of the study from 4% in 2005-2006, 2% in 2007-2008, 8% in 2009-2010 and 26% in 2011-2012 (p for trend <0.001). There was no change in rates of multimodal MRI imaging as one academic medical center accounted for >80% of all studies. Conclusions: Among acute stroke patients presenting in the time window for TPA use, noncontrast CT was the most common initial imaging strategy in clinical practice in the 2005-2012 time period, though use of concomitant CTA grew to one-quarter of cases.

Cost-effectiveness of initial stress cardiovascular MR, stress SPECT or stress echocardiography as a gate-keeper test, compared with upfront invasive coronary angiography in the investigation and management of patients with stable chest pain: mid-term outcomes from the CECaT randomised controlled trial

ObjectivesTo compare outcomes and cost-effectiveness of various initial imaging strategies in the management of stable chest pain in a long-term prospective randomised trial.SettingRegional cardiothoracic referral centre in the east of...

Standard strategies for acute ischemic stroke within the rtPA therapeutic window: Australia.

The standard approach to the assessment and implementation of therapeutic strategies for acute stroke within 4.5 hours is to adhere to a local protocol developed jointly by staff from the prehospital emergency service, hospital emergency department (ED), neuroradiology service, and acute stroke team. The protocol includes systems to receive early notification by paramedical staff, high-priority transportation and triage, rapid referral from ED staff to the stroke team, and immediate access to brain imaging.1 Plain CT brain scan remains the standard initial imaging strategy, but some specialist centers adopt advanced brain imaging (e.g., CT perfusion, MRI diffusion and perfusion) in a quest to improve selection for thrombolytic therapy.

Intussusception in children: cost-effectiveness of ultrasound vs diagnostic contrast enema

Purpose The aim of the study was to compare the cost-effectiveness of different imaging strategies for the diagnosis of pediatric intussusception using a decision analytic model. Methods A Markov decision model was constructed to model effects of radiation exposure at the time of intussusception in a hypothetical cohort of 2-year-old children. The 2 strategies compared were ultrasound followed conditionally by contrast enema (US/CE) vs contrast enema (CE) alone. The model simulated short-term and long-term outcomes of the patients, calculating the average quality-adjusted life years (QALYs) and health care costs associated with each arm. Results The use of ultrasound as a first-line diagnostic modality would result in a decrease of 79.3 and 59.7 cases of radiation-induced malignancy per 100,000 male and female children evaluated, respectively. For male and female children with intussusception, US/CE was both the most costly initial imaging strategy and the most effective compared with CE. The incremental cost-effectiveness ratios of US/CE to CE was $70,100 (boy) and $92,227 (girl) per quality-adjusted life years gained. Conclusions In a Markov decision model of pediatric acute intussusception, initial US/CE was both the most costly and the most effective strategy.

21-Year-Old Man With Chest Pain, Respiratory Distress, and Altered Mental Status

21-Year-Old Man With Chest Pain, Respiratory Distress, and Altered Mental Status

Optimal management strategy for use of compression US for deep venous thrombosis in symptomatic patients: A cost-effectiveness analysis

The authors' purpose was to identify the optimal strategy for using compression ultrasonography (US) in patients suspected of having deep venous thrombosis (DVT). The authors developed a decision-analytic model representing the natural history of DVT and the benefits and risks of anticoagulation therapy. They evaluated six initial imaging strategies: (a) unilateral examination of the common femoral and popliteal veins; (b) unilateral examination of the common femoral, popliteal, and femoral veins; (c) bilateral examination of the common femoral and popliteal veins; (d) bilateral examination of the common femoral, popliteal, and femoral veins; (e) complete unilateral examination of the symptomatic leg (including calf veins); and (f) complete bilateral examination of both legs. For 65-year-old men with unilateral symptoms of DVT, the most effective strategy was bilateral examination of the common femoral and popliteal veins with anticoagulation therapy in patients with proximal DVT and follow-up bilateral examination of the common femoral and popliteal veins in patients without an initial diagnosis of DVT with an incremental cost-effectiveness ratio of $39,000 per quality-adjusted life year gained. These results suggest that bilateral examination limited to the common femoral and popliteal veins, with follow-up bilateral examination limited to the common femoral and popliteal veins, was as cost-effective as other well-accepted medical interventions. The results were sensitive to the distribution of clot, diagnostic accuracy of compression US, and probability of bleeding with long-term morbidity.