Osteoarthritis (OA) affects over30 million peopleand is the most common cause of disability in adults in the U.S. The Arthritis Foundation has set the goal ofadvancing OA treatmentsas one of its highest priorities, making it one of the Foundation’s four scientific initiatives. To do this, we have created the OA Center of Excellence (COE), where researchers from around the county can join the Clinical Trial Network to work together to accelerate the development of new OA therapies.
OA COE目前正在资助三项临床试验网络示范研究，可能导致更好的诊断和早期治疗。来自六个不同机构的研究人员将在这些前沿研究的各个方面进行合作。我们将在一系列博客中逐一介绍这些研究。
Dr. Xiaojuan Li is the principal investigator of the study “Multi-site Multi-Vendor Cross-validation of Cartilage T1rho and T2 imaging”. The team, made up investigators from four sites (the Cleveland Clinic Foundation [CCF] in Ohio, the University of California San Francisco, the University of Kentucky, and the University Hospital for Albert Einstein College of Medicine in New York) are working to quantify biomarker assessments in cartilage images obtained throughmagnetic resonance imaging (MRI). The study will take about six months to complete.
与其他成像方法相比，MRI的优势在于能够看到软骨，以及肌肉、肌腱和骨骼。关节软骨非常薄，由细胞(软骨细胞)、蛋白质、水和其他分子组成，帮助它保持水分和维持其结构。保持水分对软骨至关重要，以维持关节健康和保护骨骼。
The most common MRI images are collected from two types of scans: T1-weighted and T2-weighted scans. Generally, T1-weighted images look at only fat tissue, while T2-weighted images look at fat and water in the tissue (cartilage). These currently used techniques are limited to evaluate structural changes of cartilage (like cartilage thinning and fissuring).
Dr. Li and the investigative team are evaluating new techniques with T1rho and T2 imaging which can detect biochemical changes within the cartilage matrix before structural changes can be seen. These biochemical changes represent promising biomarkers that are more sensitive for detecting thevery early stages of OA, and for evaluating cartilage changes after treatment (treatment response).
T1rho and T2 measures and test result interpretation can vary based on many factors. Things like the positioning of the patient, the temperature of the room where the images are taken, and many other factors can affect results. Test results can also vary from radiologist to radiologist, partially due to the differences in the equipment made by different manufacturers for these tests. The team will standardize procedures (like patient positioning, room temperature, etc.) and will compare the imaging results obtained from three different imaging manufacturers commonly used around the U.S. (Siemens, Philips, and GE). The team is interested in seeing how much difference there may be between test results obtained.
The team will use T1rho and T2 measures as imaging biomarkers. They plan to do scans of 5 subjects at each site. There will also be 2 or 3 traveling subjects who will be imaged at all four sites (to compare sites). The first human subject was recently enrolled and scanned at CCF. The team expects to complete scans of all human subjects by May 2018.
Each site will also have man-made “phantom” joints made from material similar to human cartilage. This will allow them to calibrate and standardize the imaging machines across sites. The phantoms also allow each site to take multiple images with a joint with known parameters, as often as needed.
Dr. Li and her team will attempt to quantify these imaging biomarkers to create algorithms to standardize the measures. Once this is done, the standard measures can become automated, making test result interpretations consistent.
Dr. Li works in the biomedical engineering department, and directs the program of advanced musculoskeletal imaging (PAMI) of the CCF in Ohio.
Related Resources:
- Arthritis Foundation: Advancing Osteoarthritis Treatments
- Researchers on the Path to a Cure – Spotlight on Dr. Caroline Jefferies
- Researchers on the Path to a Cure – Spotlight on Dr. Edward Doherty