Cedars-sinai Medical Center

University of California

California Institute of Technology

Warren S Grundfest

Zachary D Taylor

Vasilis Z Marmarelis

Sandor G Vari

Shijun Sung

Joel W Burdick

Andrew Brett Slatkin

Maie St John

Ramez E N Shehada

Neha Bajwa

Ramez E Shehada

Weiqiang Shi

Theodore Papazoglou

James Garritano

Bryan Nowroozi

Priyamvada Tewari

Oscar Magnus Stafsudd

Jean-Michel I Maarek

Laura Marcu

Martin Culjat

Rahul Singh

Jean L Bourges

Jean P Hubschman

Pei-Chi Jiang

Wendy J Snyder

Asael Papour

Marigo Stavridi

George Saddik

Ashkan Maccabi

Zachary Deis Taylor

A vibro-acoustography imaging system that generates a map of the mechanical response of a target to an acoustic radiation force, usually in low kHz range by a confocal geometry. The system generates two focused sinusoidal beams to produce a stress field at the beat frequency, which is a function of vibration and acoustic emissions field in terms of mechanical properties. A highly sensitive hydrophone is then used for detection of the acoustic emissions field, the amplitude of which may be correlated to the mechanical properties of the target tissue.

Multi-frequency harmonic acoustography for target identification and border detection

Systems, methods and apparatuses for performing wound analysis using THz imaging are provided. Due to the large complex component of water's dielectric constant in the THz regime, and the relative frequency invariance of non-aqueous tissue constituents, this modality is highly sensitive to the water content of tissue. It has been found that using THz imaging turns the presence of edema into a contrast mechanism, and allows for the use of the spatial distributions of edema to assess wound status immediately. Apparatus and methods enable earlier diagnosis of wound status which could result in accelerated treatment and shorter overall hospital stays.

Assessment of wound status and tissue viability via analysis of spatially resolved THz reflectometry maps

Methods and apparatus for corneal imaging and sensing are provided. Apparatus capable of utilizing single or multiple frequency emissions at terahertz (THz) wavelengths to create reflectivity maps of the cornea in either a contact or non-contact modes are also provided. Methods of obtaining data from THz imaging and sensing apparatus about the corneal tissue-aqueous humor system, including information about the corneal tissue water content (CTWC) and/or the central corneal thickness (CCT) are likewise provided. Methodologies may use multiple transfer functions (frequencies) in obtaining simultaneous data about CTWC and CCT. Methods using frequency sweeping to allow for determination of CTWC and CCT may also be utilized. Methods may also be used to assess CTWC using multiple bandwidths at the same frequency, or multiple frequencies at the same bandwidth. Methods may use data from CTWC measurements to aid in the diagnosis of various corneal and brain disorders.

THz sensing of corneal tissue water content

Methods and systems for single beam scanning capable of imaging the surface of a spherical body of arbitrary radius of curvature are provided. The spherical imaging methods and systems utilize one or more off-axis parabolic (OAP) mirror to perform a geometrical transformation of the spherical surface to a flat rectilinear imaging coordinate grid such that the single scanning beam maintains a normal incidence across the curved field of view of the spherical body. The imaging methods and systems project the spherical surface to a Cartesian plane and then the remapped surface is rapidly imaged by raster-scanning an illumination beam in the rectangular coordinate such that the OAP mirror produces a rectilinear image of the target. The imaging of the spherical surface is accomplished while maintaining the target, illumination source, and detector in a stationary position. The imaging systems and methods may utilize a single source and a single detector, and may incorporate a THz illumination source. The beam scanning imaging systems and methods may be applied to corneal tissue imaging.

Scanning method for uniform, normal-incidence imaging of spherical surface with a single beam

A time-resolved fluorescence imaging (TRFI) system that images a target medium without lifetime fitting. Instead of extracting the lifetime precisely, the system images the fluorophore distribution to allow for a simple and accurate method to obtain the fluorescence image without lifetime-extraction for time-resolved fluorescence imaging. An illumination source circuit for TRFI is also disclosed that shapes the excitation pulse. In one embodiment, the illumination source comprises an LED and stub line configured for generating a linear decay profile.

System and method for time-resolved fluorescence imaging and pulse shaping

A corneal hydration sensing system includes an illumination system configured to provide an illumination beam of terahertz radiation, an optical system arranged in an optical path of the illumination system to relay and direct at least a portion of the illumination beam of terahertz radiation onto a cornea of a subject and to receive at least a portion of terahertz radiation reflected from the cornea to provide a return beam of terahertz radiation, and a detection system arranged in an optical path of the return beam of terahertz radiation. The detection system is configured to provide a detection signal from detecting at least a portion of the return beam of terahertz radiation. The corneal hydration sensing system also includes a signal processing system configured to communicate with the detection system to receive the detection signal. The signal processing system processes the detection signal to provide a measure of an amount of hydration sensed in the cornea of the subject.

Corneal hydration sensing system

The Laser Induced Fluorescence Attenuation Spectroscopy (LIFAS) method and apparatus preferably include a source adapted to emit radiation that is directed at a sample volume in a sample to produce return light from the sample, such return light including modulated return light resulting from modulation by the sample, a first sensor, displaced by a first distance from the sample volume for monitoring the return light and generating a first signal indicative of the intensity of return light, a second sensor, displaced by a second distance from the sample volume, for monitoring the return light and generating a second signal indicative of the intensity of return light, and a processor associated with the first sensor and the second sensor and adapted to process the first and second signals so as to determine the modulation of the sample. The methods and devices of the inventions are particularly well-suited for determining the wavelength-dependent attenuation of a sample and using the attenuation to restore the intrinsic laser induced fluorescence of the sample. In turn, the attenuation and intrinsic laser induced fluorescence can be used to determined a characteristic of interest, such as the ischemic or hypoxic condition of biological tissue.

Method and devices for laser induced fluorescence attenuation spectroscopy

Methods and devices for Laser Induced Fluorescence Attenuation Laser Induced Fluorescence Attenuation Spectroscopy (LIFAS) Spectrocopy, including, in particular, methods and devices for the detection of ischemia and hypoxia in biological tissue. The LIFAS method and apparatus preferably include a source adapted to emit radiation that is directed at a sample volume in a sample to produce return light from the sample, such return light including modulated return light resulting from modulation by the sample, a first sensor, displaced by a first distance from the sample volume for monitoring the return light and generating a first signal indicative of the intensity of return light, a second sensor, displaced by a second distance from the sample volume for monitoring the return light and generating a second signal indicative of the intensity of return light, and a processor associated with the first sensor and the second sensor and adapted to process the first and second signals so as to determine the modulation of the sample. The methods and devices of the inventions are particularly well-suited for determining the wavelength-dependent attenuation of a sample and using the attenuation to restore the intrinsic laser induced fluorescence of the sample. In turn, the attenuation and intrinsic laser induced fluorescence can be used to determined a characteristic of interest, such as the ischemic or hypoxic condition of biological tissue.

Method and devices for laser induced fluorescence attenuation spectroscopy (LIFAS)

A method of analysis of organic matter, called Time-Resolved, Laser-Induced Fluorescence Spectroscopy (TR-LIFS), characterizes and discriminates certain matter, such as tissue, by investigating the fluoresence response of the protein and lipid fluorophore components in both the spectral domain and time domain. This method is more robust than prior methods as (1) can investigate the matter at muplitple wavelengths and even across an entire spectrum and (2) is more sensitive to picking up weaker fluorescence signals such as that from lipids. A detailed study of the use of TR-LIFs for the charaterization of arterial wall tisse is described. A system and instrumentation for practicing the novel method is also disclosed.

Time-resolved, laser-induced fluorescence for the characterization of organic material

A glucose monitor, and related method, determines the concentration of glucose in a sample with water, using a predictive regression model. The glucose monitor illuminates the sample with ultraviolet excitation light that induces the water and any glucose present in the sample to emit return light that includes raman scattered light and glucose emission or fluorescence light. The return light is monitored and processed using a predictive regression model to determine the concentration of glucose in the sample. The predictive regression model accounts for nonlinearities between the glucose concentration and intensity of return light within different wavelength bands at a predetermined excitation light energy or the intensity of return light within a predetermined wavelength band at different excitation energy levels. A fiber-optic waveguide is used to guide the excitation light from a laser excitation source to the sample and the return light from the sample to a sensor.

Glucose monitoring apparatus and method using laser-induced emission spectroscopy

Method and devices for laser induced fluorescence attenuation

An ultrasonic transducer orientation sensing and display apparatus, and related method, for use in providing an accurate representation of the orientation of an ultrasonic transducer's imaging plane. The orientation sensing and display apparatus includes an ultrasonic transducer having an integral orientation sensor, a processor, and a display. The representation of the imaging plane as indicated on the display is based on electrical signals generated by the orientation sensor. The ultrasonic transducer, in accordance with one embodiment of the present invention, is integrated near the distal end or tip of an elongated tube of a laparoscopic instrument used for ultrasonic imaging. The orientation sensor is a biaxial gravitational sensor, composed of two orthogonal sensing toroids to sense rotation about any axis lying in a horizontal plane. Each sensing toroid has a hollow tubular shape that contains a gravity indicator that is free to move within the respective sensing toroid for measuring rotation about an axis through the toroid's center. Gravity causes each gravity indicator to migrate to the lowest portion of the respective toroid. The orientation also can include a permanent magnet thus providing a tri-axial sensor.

Ultrasonic transducer orientation sensing and display apparatus and

A robot for performing endoscopic procedures in flexible and curved human or animal lumens. A plurality of segments are attached to each other. Traction segments embrace the lumen walls. Other segments include actuators that cause the endoscope to locally deform its shape via bending, extending, or some combination of bending and extension. A method is provided to sequence the action of the segments to cause inchworm-like or snake-like locomotion, or a combination of them through a curved and flexible lumen. The method of movement can be adapted to the lumen characteristics, or to obviate a component failure. A compressed gas line attached to the back segment provides compressed gas for insufflation of the lumen, and can optionally be used to drive the actuators that control the operation of the endoscope segments. The lead segment may include television cameras, ultrasound transducers, biopsy arms, drug delivery systems, or other sensors, diagnostic aids, therapeutic devices, and surgical tools. Medical instruments and sensors can also be placed in the rear or middle segments.

Robotic endoscopy

A compact solid state source of coherent laser light in the range of about 298 nm through about 355 nm utilizes a Nd:YAG or Nd:YLF laser to pump a tunable Ti:Al.sub.2 O.sub.3 laser. The beam from the Nd:YAG/Nd:YLF laser is then combined in a nonlinear optical crystal with the tunable beam from the Ti:Al.sub.2 O.sub.3 laser to provide a continuously tunable laser beam in the range of about 298 nm through about 355 nm.

Continuously tunable solid state ultraviolet coherent light source

A medical monitor, and related method, determines a pre-existing physiological property of an organ of a patient by monitoring fluorescent light produced by constituents associated with the metabolic and structural condition of the organ. The monitor illuminates the organ with ultraviolet excitation light that induces some constituents of the organ to fluoresce, with the fluorescent light being monitored and processed to determine pre-existing physiological properties of the organ. A sensor monitors the return light, which includes fluorescent light produced by the fluorescent constituents of the organ, and generates first and second electrical signals indicative of the intensity of light at two wavelength. One wavelength is associated with the fluorescence of collagen, a constituent associated with organ's structural properties, and the other wavelength is a associated with the fluorescence of NADH, a constituent associated with the organ's metabolism. A processor then processes the first and second electrical signals to determine the localized pH of the organ. A fiber-optic waveguide is used to guide the excitation light from the laser light source to the organ and the return light from the organ to the sensor. In another aspect of the invention, the sensor generates a third electrical signal associated with the fluorescence of elastin, a constituent associated with the organ's structural properties. The processor processes the first, second and third electrical signals to determine the perfusion or oxygenation of the organ.

Growing community of inventors

Los Angeles, CA, United States of America

Warren S Grundfest