Artificial intelligence model for segmentation and severity scoring of osteophytes in hand osteoarthritis on ultrasound images

ObjectiveTo develop an artificial intelligence (AI) model able to perform both segmentation of hand joint ultrasound images for osteophytes, bone, and synovium and perform osteophyte severity scoring following the EULAR-OMERACT grading system (EOGS) for hand osteoarthritis (OA).MethodsOne hundred sixty patients with pain or reduced function of the hands were included. Ultrasound images of the metacarpophalangeal (MCP), proximal interphalangeal (PIP), distal interphalangeal (DIP), and first carpometacarpal (CMC1) joints were then manually segmented for bone, synovium and osteophytes and scored from 0 to 3 according to the EOGS for OA. Data was divided into a training, validation, and test set. The AI model was trained on the training data to perform bone, synovium, and osteophyte identification on the images. Based on the manually performed image segmentation, an AI was trained to classify the severity of osteophytes according to EOGS from 0 to 3. Percent Exact Agreement (PEA) and Percent Close Agreement (PCA) were assessed on individual joints and overall. PCA allows a difference of one EOGS grade between doctor assessment and AI.ResultsA total of 4615 ultrasound images were used for AI development and testing. The developed AI model scored on the test set for the MCP joints a PEA of 76% and PCA of 97%; for PIP, a PEA of 70% and PCA of 97%; for DIP, a PEA of 59% and PCA of 94%, and CMC a PEA of 50% and PCA of 82%. Combining all joints, we found a PEA between AI and doctor assessments of 68% and a PCA of 95%.ConclusionThe developed AI model can perform joint ultrasound image segmentation and severity scoring of osteophytes, according to the EOGS. As proof of concept, this first version of the AI model is successful, as the agreement performance is slightly higher than previously found agreements between experts when assessing osteophytes on hand OA ultrasound images. The segmentation of the image makes the AI explainable to the doctor, who can immediately see why the AI applies a given score. Future validation in hand OA cohorts is necessary though

Acute hypoxia increases the cerebral metabolic rate:a magnetic resonance imaging study

The aim of the present study was to examine changes in cerebral metabolism by magnetic resonance imaging of healthy subjects during inhalation of 10% O(2) hypoxic air. Hypoxic exposure elevates cerebral perfusion, but its effect on energy metabolism has been less investigated. Magnetic resonance imaging techniques were used to measure global cerebral blood flow and the venous oxygen saturation in the sagittal sinus. Global cerebral metabolic rate of oxygen was quantified from cerebral blood flow and arteriovenous oxygen saturation difference. Concentrations of lactate, glutamate, N-acetylaspartate, creatine and phosphocreatine were measured in the visual cortex by magnetic resonance spectroscopy. Twenty-three young healthy males were scanned for 60 min during normoxia, followed by 40 min of breathing hypoxic air. Inhalation of hypoxic air resulted in an increase in cerebral blood flow of 15.5% (p = 0.058), and an increase in cerebral metabolic rate of oxygen of 8.5% (p = 0.035). Cerebral lactate concentration increased by 180.3% ([Formula: see text]), glutamate increased by 4.7% ([Formula: see text]) and creatine and phosphocreatine decreased by 15.2% (p [Formula: see text]). The N-acetylaspartate concentration was unchanged (p = 0.36). In conclusion, acute hypoxia in healthy subjects increased perfusion and metabolic rate, which could represent an increase in neuronal activity. We conclude that marked changes in brain homeostasis occur in the healthy human brain during exposure to acute hypoxia

Hepatitis C prevalence in Denmark -an estimate based on multiple national registers

Background: A national survey for chronic hepatitis C has not been performed in Denmark and the prevalence is unknown. Our aim was to estimate the prevalence of chronic hepatitis C from public registers and the proportion of these patients who received specialized healthcare. Methods: Patients with a diagnosis of chronic hepatitis C were identified from four national registers: a laboratory register, the Hospital Discharge Register, a clinical database of chronic viral hepatitis and the Register of Communicable Diseases. The total population diagnosed with hepatitis C was estimated by capture-recapture analysis. The population with undiagnosed hepatitis C was derived from the national register of drug users by comparing diagnosed and tested persons. Results: A total of 6,935 patients diagnosed with chronic hepatitis C were identified in the four registers and the estimated population diagnosed with the disease was 9,166 persons (95% C.I. interval 8,973 – 9,877), corresponding to 0.21% (95% CI 0.21%-0.23%) of the Danish population over 15years of age. The prevalence was highest among persons 40–49years old (0.39%) and males (0.28%). It was estimated that 40% of the diagnosed patients lived in the capital region, and 33.5% had attended specialised healthcare. It was estimated that 46% of hepatitis C patients had not been diagnosed and the total population with chronic hepatitis C in Denmark was 16,888 (95% C.I. 16,474-18,287), corresponding to 0.38% (95% CI 0.37-0.42) of the population over 15years of age. Conclusions: The estimated prevalence of chronic hepatitis C in Denmark was 0.38%. Less than half of the patients with chronic hepatitis C in Denmark have been identified and among these patients, one in three has attended specialised care

Infliximab biosimilar-to-biosimilar switching in patients with inflammatory rheumatic disease:clinical outcomes in real-world patients from the DANBIO registry

OBJECTIVE: Successful uptake of biosimilars in rheumatology is limited by lack of real-world evidence regarding effectiveness of biosimilar-to-biosimilar switching. We investigated infliximab biosimilars CT-P13-to-GP1111 switching among patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA). METHODS: Observational cohort study from the DANBIO registry. Patients were classified as originator-naïve or originator-experienced. Retention rates of 1-year GP1111 treatment were explored (Kaplan-Meier). We identified baseline factors (at the time of switch) associated with withdrawal of GP1111 (multivariable Cox-regression analyses with HRs including originator treatment history). Changes in subjective and objective measures of disease activity 4 months before and after the switch were assessed in individual patients. RESULTS: Of 1605 patients (685 RA, 314 PsA and 606 AxSpA, median disease duration was 9 years, 37% in Clinical Disease Activity Index/Ankylosing Spondylitis Disease Activity Score remission), 1171 were originator-naïve. Retention rates at 1-year were 83% (95% CI: 81% to 85%) and 92% (95% CI: 90% to 95%) for the originator-naïve and originator-experienced, respectively. GP1111 retention rates were higher in originator-experienced compared to originator-naïve with RA (HR=0.4 (95% CI: 0.2 to 0.7)) and PsA (HR=0.2 (95% CI: 0.1 to 0.8)), but not significantly for AxSpA: HR=0.6 (95% CI: 0.3 to 1.2). Lower disease activity was associated with higher retention. Changes in disease activity preswitch and postswitch were close to zero. CONCLUSION: This real-world observational study of more than 1600 patients with inflammatory arthritis showed high 1-year retention following a nationwide infliximab biosimilar-to-biosimilar switch. Retention was higher in originator-experienced and in patients with low disease activity, suggesting outcomes to be affected by patient-related rather than drug-related factors

Data from: Neuromuscular adverse events associated with Anti-PD-1 monoclonal antibodies: systematic review

Neuromuscular adverse events following cancer treatment with anti–programmed cell death protein 1 (PD-1) monoclonal antibodies are relatively rare, yet potentially fatal. We performed a systematic review to characterize the clinical presentation, diagnostic workup, and management of neuromuscular disorders (NMDs) in patients treated with nivolumab or pembrolizumab monotherapy or concurrent with other immunologic agents, such as ipilimumab. Sixty-one publications on 85 patients (mean age 66.9 years [range 34–86]; male/female 2.6:1; 59% metastatic melanoma) were identified from selected indexing databases until June 2018. Forty-eight patients had received nivolumab and 39 pembrolizumab. The mean number of PD-1 inhibitor treatment cycles prior to onset of symptoms was 3.6 (range 1–28). Symptoms included oculomotor (47%), respiratory (43%), bulbar (35%), and proximal weakness (35%), as well as muscle pain (28%). Diagnoses were categorized as myasthenia gravis (27%), neuropathy (23%), myopathy (34%), or a combination of these (16%). After a critical review of the data, however, evidence did not support the stated NMD diagnosis in 13% of cases, while up to 25% of patients had signs of additional NMDs. Cardiac complications occurred in more than 30% of patients diagnosed with myasthenia gravis or myositis. Mortality was high in these patients, despite adequate treatment strategies including corticosteroid, IV immunoglobulins, and plasma exchange. The clinical presentation of NMDs associated with PD-1 inhibitors is often atypical, with considerable overlap between myasthenia gravis and myopathy, and cardiac/respiratory complications are common