Structured Illumination Imaging for in-vitro Microscopy and in-vivo Retinal Imaging

Brief Description:
In structured illumination microscopy, an object is illuminated by sinusoidally patterned light, rather than conventional uniform illumination, and digital image processing is done to obtain axial sectioning (3D imaging) and super-resolution (imaging at frequencies beyond the normal diffraction cutoff of the optical system).

The technique can be used in microscopes for imaging both fluorescent and non-fluorescent objects, such as tissues, cells and micro-structures such as semiconductor chips, in both in vitro and in vivo applications.
A key in vivo application is retinal imaging of the human eye.  Retinal imaging is used to diagnose retinal disease, such as diabetic macular edema, retinitis pigmentosa, age-related macular degeneration (AMD) and glaucoma.
Structured illumination imaging has been used before in in vitro fluorescent microscopy to obtain super resolution but this is the first time this is being done in vivo on a constantly moving subject, such as a living human eye, and for non-fluorescent objects.

Applied to the human eye, this technology enables the imaging of individual cells and retinal structures smaller than 2 microns, such as rods, foveal cones, fine blood capillaries and ganglion cell axions, which are difficult to resolve in vivo because the patient’s pupil, which is the limiting aperture in the optical system, cannot typically be dilated beyond 6 to 8 mm.   Our technology includes image processing for image registration to address the motion of the eye and the reduction of the speckle defect related to coherent laser illumination.   It does not require that the cells be made fluorescent.  The technique is compatible with adaptive optics used to correct for the aberrations of the eye.  Current ophthalmoscopes and fundus cameras used by doctors for examining the retina have low resolution and can only detect disease when it is at an advanced stage.  This technology takes the resolution to the cellular level below 2 microns and is expected to enable diagnosis at an early stage for more effective treatment.  Current confocal imaging techniques also provide axial sectioning (3D imaging) through the different layers of the retina, but these confocal systems are complex and expensive compared to this structured illumination / digital signal processing technique.
Applied to in vitro microscopy, the technique will provide axial sectioning, and super-resolution for both fluorescent and non-fluorescent objects.   Current microscopes with structured illumination require fluorescent objects and only perform axial sectioning, and do not provide lateral super-resolution.
URV Reference Number: 1-11030-07033
Patent Information:
Title Country Patent No. Issued Date
Structured Illumination for Imaging or Stationary and Non-Stationary, Fluorescent and Non-Fluorescent Objects United States 8,279,329 10/2/2012
For Information, Contact:
John Fahnervihtelic
Senior Licensing Manager
University of Rochester
David Williams
Sapna Shroff
James Fienup