ABSTRACT
Nonlinear microscopy is a non-invasive imaging technique which allows a visualization of biological tissue with high signal contrast due to spectral separation combined with high resolution. In addition to two-photon fluorescence and second harmonic signals also four-wave mixing signals can be used for imaging ocular structures. This review article presents the physical principles of different contrast mechanisms. Exemplary experimental results based on various nonlinear signals are shown, opportunities of this technology are discussed and the prospect of translating this imaging technique into a clinical application is addressed.
Subject(s)
Eye Diseases/pathology , Image Enhancement/instrumentation , Microscopy, Confocal/instrumentation , Microscopy, Fluorescence, Multiphoton/instrumentation , Ophthalmoscopes , Equipment Design , Equipment Failure Analysis , Humans , Image Enhancement/methods , Microscopy, Confocal/methods , Microscopy, Fluorescence, Multiphoton/methods , Nonlinear Dynamics , Technology Assessment, BiomedicalABSTRACT
Osteonecrosis (ON) is a devastating illness that can lead to severe joint disease in young patients. The pathogenesis of ON is largely unknown; however, there have been numerous reports associating risk factors including systemic lupus erythematosus (SLE) with the disease. The risk of ON for SLE patients is believed to be a result of both the SLE disease state itself and the concomitant use of corticosteroids. The objective of osteonecrosis treatment is typically to halt progression or delay the onset of end-stage arthritis that may require a total joint arthroplasty (TJA). Joint-preserving procedures are attempted for pre-collapse and some post-collapse lesions. After severe subchondral collapse has occurred, TJA is often necessary to relieve pain. The purpose of this article is to draw attention to recent evidence regarding several treatment options for the management of SLE-associated ON, including lesion observation, medication, joint-preserving techniques, and TJA.