Optical coherence tomography (OCT) has long been used as a diagnostic tool in the field of ophthalmology. The ability to observe microstructural changes in the tissues of the eye has proved very effective in diagnosing ocular disease. However, this technology has yet to be introduced into the primary care office, where indications of disease are first encountered. We have developed a portable, handheld imaging probe for use in the primary care setting and evaluated its tissue site accessibility, ability to observe diseased tissue, and screening capabilities in in vivo human patients, particularly for pathologies related to the eye, ear and ...

High-resolution real-time tomography of scattering tissues is important for many areas of medicine and biology 1 , 2 , 3 , 4 , 5 , 6 . However, the compromise between transverse resolution and depth-of-field, in addition to low sensitivity deep in tissue, continues to impede progress towards cellular-level volumetric tomography. Computed imaging has the potential to solve these long-standing limitations. Interferometric synthetic aperture microscopy 7 , 8 , 9 is a computed imaging technique enabling high-resolution volumetric tomography with spatially invariant resolution. However, its potential for clinical diagnostics remains largely untapped because full volume reconstructions required lengthy post-processing, and the phase-stability requirements have been difficult to satisfy ...

Magnetomotive optical coherence tomography (MM-OCT) is a functional extension of OCT which utilizes magnetically responsive materials that are modulated by an external magnetic field for contrast enhancement and for elastography to assess the structural and viscoelastic properties of the surrounding tissues. Traditionally, magnetomotive contrast relies on the interaction between the displacement of magnetic particles induced by an external magnetic field and the micro-environmental restoring (elastic) force acting on the particles. When the restoring force from a sample containing magnetic particles is weak or non-existent, the MM-OCT signal-to-noise ratio (SNR) can degrade significantly. We have developed a novel solenoid configuration to ...

Background: Partial mastectomy is the most commonly performed procedure for invasive breast cancer and is associated with a reexcision rate commonly ranging from 20% to 40% in the literature. This high rate of reexcision is associated with significant additional cost (estimated over $4,000 per reexcision) and lower quality outcomes. Optical coherence tomography (OCT) is a high-resolution imaging technology that images tissue structure with micron-scale resolution – on the same scale as histopathology. It is similar to ultrasound except it uses near infra-red light waves instead of sound waves to create detailed images several millimeters deep into tissue. Although widely used ...

We present a method for the numerical correction of optical aberrations based on indirect sensing of the scattered wavefront from point-like scatterers (“guide stars”) within a three-dimensional broadband interferometric tomogram. This method enables the correction of high-order monochromatic and chromatic aberrations utilizing guide stars that are revealed after numerical compensation of defocus and low-order aberrations of the optical system. Guide-star-based aberration correction in a silicone phantom with sparse sub-resolution-sized scatterers demonstrates improvement of resolution and signal-to-noise ratio over a large isotome. Results in highly scattering muscle tissue showed improved resolution of fine structure over an extended volume. Guide-star-based computational adaptive ...

A system and method for microscale measurement and imaging of the group refractive index of a sample. The method utilizes a broadband confocal high-numerical aperture microscope embedded into an interferometer and a spectrometric means, whereby spectral interferograms are analyzed to compute optical path delay of the beam traversing the sample as the sample is translated through the focus of an interrogating light beam. A determination of group refractive index may serve to disambiguate phase ambiguity in a measurement of refractive index at a specified wavelength. Spatial resolution of object characterization in three dimensions is achieved by imaging the object from ...

Otitis media (OM), a middle-ear infection, is the most common childhood illness treated by pediatricians. If inadequately treated, OM can result in long-term chronic problems persisting into adulthood. Children with chronic OM or recurrent OM often have conductive hearing loss and communication difficulties and require surgical treatment. Tympanostomy tube insertion, the placement of a small drainage tube in the tympanic membrane (TM), is the most common surgical procedure performed in children under general anesthesia. Recent clinical studies have shown evidence of a direct correspondence between chronic OM and the presence of a bacterial biofilm within the middle ear. Biofilms are ...