Subject(s)
Adrenal Cortex Hormones/therapeutic use , Asthma/drug therapy , Cholecalciferol/therapeutic use , Vitamin D Deficiency/drug therapy , Asthma/complications , Asthma/immunology , Asthma/metabolism , CD4-Positive T-Lymphocytes/drug effects , CD4-Positive T-Lymphocytes/immunology , Dendritic Cells/drug effects , Dendritic Cells/immunology , Gene Expression , Humans , Interferon-gamma/genetics , Interferon-gamma/immunology , Interleukins/genetics , Interleukins/immunology , Monocytes/drug effects , Monocytes/immunology , Transforming Growth Factor beta/genetics , Transforming Growth Factor beta/immunology , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/immunology , Vitamin D Deficiency/complications , Vitamin D Deficiency/immunology , Vitamin D Deficiency/metabolismABSTRACT
Current treatments for osteoarthritis are pain relief and total joint arthroplasty. There is a clinical need for early osteoarthritis diagnostic methods for potential preventive interventions. The resolution achieved with radiography, magnetic resonance imaging (MRI), and arthroscopy is too limited for the assessment of early disease. The high resolution, small fiber-optic probes, and real-time imaging of optical coherence tomography (OCT) makes this method ideal for assessing articular cartilage. In this article, we describe in vivo human arthroscopic OCT with qualitative baseline comparisons made with MRI and arthroscopy. Two-year MRI follow-ups are under way to quantitatively compare OCT with MRI and to assess the long-term outcomes of changes noted in the OCT images.
Subject(s)
Arthroscopy/methods , Knee Joint/diagnostic imaging , Magnetic Resonance Imaging/methods , Osteoarthritis, Knee/diagnostic imaging , Tomography, Optical Coherence/methods , Adult , Cartilage, Articular/diagnostic imaging , Cartilage, Articular/pathology , Female , Humans , Image Processing, Computer-Assisted , Knee Joint/pathology , Male , Middle Aged , Osteoarthritis, Knee/pathology , Patient Selection , RadiographyABSTRACT
Optical coherence tomography (OCT) has demonstrated considerable potential for a wide range of medical applications. Initial work was done in the time domain OCT (TD-OCT) approach, but recent interest has been generated with spectral domain OCT (SD-OCT) approaches. While SD-OCT offers higher data acquisition rates and no movable parts, we recently pointed out theoretical inferior aspects to its performance relative to TD-OCT. In this paper we focus on specific limitations of swept source OCT (SS-OCT), as this is the more versatile of the two SD-OCT embodiments. We present experimental evidence of reduced imaging penetration, increased low frequency noise, higher multiple scattering (which can be worsened still via aliasing), increased need to control the distance from the sample, and saturation of central bandwidth frequencies. We conclude that for scenarios where the dynamic range is relatively low (e.g., retina), the distance from the sample is relatively constant, or high acquisition rates are needed, SS-OCT has a role. However, when penetration remains important in the setting of a relatively high dynamic range, acquisition rates above video rate are not needed, or the distance to the tissue is not constant, TD-OCT may be the superior approach.
