Improving reference standards for validation of AI-based radiography

Objective:Demonstrate the importance of combining multiple readers'' opinions, in a context-aware manner, when establishing the reference standard for validation of artificial intelligence (AI) applications for, e.g. chest radiographs. By comparing individual readers, majority vote of a panel, and panel-based discussion, we identify methods which maximize interobserver agreement and label reproducibility.Methods:1100 frontal chest radiographs were evaluated for 6 findings: airspace opacity, cardiomegaly, pulmonary edema, fracture, nodules, and pneumothorax. Each image was reviewed by six radiologists, first individually and then via asynchronous adjudication (web-based discussion) in two panels of three readers to resolve disagreements within each panel. We quantified the reproducibility of each method by measuring interreader agreement.Results:Panel-based majority vote improved agreement relative to individual readers for all findings. Most disagreements were resolved with two rounds of adjudication, which further improved reproducibility for some findings, particularly reducing misses. Improvements varied across finding categories, with adjudication improving agreement for cardiomegaly, fractures, and pneumothorax.Conclusion:The likelihood of interreader agreement, even within panels of US board-certified radiologists, must be considered before reads can be used as a reference standard for validation of proposed AI tools. Agreement and, by extension, reproducibility can be improved by applying majority vote, maximum sensitivity, or asynchronous adjudication for different findings, which supports the development of higher quality clinical research.Advances in knowledge:A panel of three experts is a common technique for establishing reference standards when ground truth is not available for use in AI validation. The manner in which differing opinions are resolved is shown to be important, and has not been previously explored.     

Acute liver injury induced by weight-loss herbal supplements

We report three cases of patients with acute liver injury induced by weight-loss herbal supplements. One patient took Hydroxycut while the other two took Herbalife supplements. Liver biopsies for all patients demonstrated findings consistent with drug-induced acute liver injury. To our knowledge, we are the first institute to report acute liver injury from both of these two types of weight-loss herbal supplements together as a case series. The series emphasizes the importance of taking a cautious approach when consuming herbal supplements for the purpose of weight loss.     

Film-free efficiency systems: a new cost-effective approach

Pressure is on healthcare providers to make their services more affordable. Streamlining operations to improve efficiency is one means of achieving that goal. PACS has been touted as the technology to improve radiologic services. Sold as a way to eliminate lost records and lower operations costs, in reality, PACS has raised costs and slowed work flow in many cases. Perhaps PACS that raise operations costs are more properly named digital overhead generating systems (DOGS). There is an alternative solution--film-free efficiency systems (FFES), defined as the technological tools required to lower radiologic costs and improve services. A new type of image and information management technology and distinct from traditional PACS in a number of ways, film-free efficiency systems are immediately cost effective. They improve personnel efficiency, reduce costs per RVU, provide an alternative to film and exclude the use of any technology that is not cost effective. Implementation of these systems must begin with a clearly stated mission, a leadership statement and financial accountability. To guarantee an immediate financial gain in your department, you'll want to finance the system through material cost savings. Implementation should start with the digital modalities. The next step is to retrain staff and reengineer the workplace, followed by creating the necessary infrastructure of PCs in referring physicians' offices. Lastly, implement CR or digital radiography as prices drop and technologies improve in speed.     

MR imaging of the knee. Part II. Chronic disorders

Sixty patients with symptoms of chronic disease of the knee joint were evaluated with high-resolution, thin-section magnetic resonance (MR) imaging. MR imaging depicted a wide variety of knee joint abnormalities including osteochondritis dissecans, medullary infarcts, epiphyseal osteonecrosis, intraarticular osteochondral fragments, synovial cysts, joint effusions, intraarticular soft-tissue tumors, synovial disease, leukemic infiltration of bone marrow, Osgood-Schlatter disease, and nonossifying fibroma. In two cases MR imaging depicted bone infarcts not seen on both radionuclide bone scans and standard radiographs. The highly detailed depiction of the articular cartilage was of particular importance in predicting arthroscopic findings in cases of osteochondritis dissecans. In two cases, a soft-tissue mass (pigmented villonodular synovitis) and a large osteochondral fragment undetected at arthroscopy were accurately localized with MR imaging. The results indicate that MR imaging is capable of providing information that might otherwise require multiple, sometimes invasive diagnostic procedures.     

The use of MRI to assist in diagnosis of pigmented villonodular synovitis of the knee joint

Pigmented villonodular synovitis (PVNS) of the knee joint remains a difficult and elusive entity to define and characterize. This entity most often appears in the young adult knee with nonspecific clinical features, including a painful range of motion and perhaps a sensation of locking. Detection and diagnosis of this localized soft-tissue mass are difficult because plain roentgenograms may be totally within normal limits. The case of a 21-year-old woman illustrates the use of magnetic resonance imaging (MRI) as an effective technique to define and characterize PVNS. Advantages of MRI include high-resolution/high-contrast multiplanar sections that depict bone, marrow, ligaments and tendons, fat, menisci, and articular cartilage in one image. In addition, MRI is noninvasive and requires no ionized radiation. MRI is an excellent clinical tool for the evaluation of intraarticular tumors of the knee joint.     

Anatomic correlations of magnetic resonance images with cadaver cryosections

The authors present here a correlation of the normal anatomy of the pelvis, as depicted by MRI in multiple planes, with corresponding cadaveric specimens.     

Partially thrombosed giant aneurysm simulating an arteriovenous malformation on MR imaging

A case of a partially thrombosed giant intracranial aneurysm with a magnetic resonance appearance simulating an arteriovenous malformation is presented. Causes for the similarity in signal pattern are discussed.