A modulated physiological sensor is a noninvasive device responsive to a physiological reaction of a living being to an internal or external perturbation that propagates to a skin surface area. The modulated physiological sensor has a detector configured to generate a signal responsive to the physiological reaction. A modulator varies the coupling of the detector to the skin so as to at least intermittently maximize the detector signal. A monitor controls the modulator and receives an effectively amplified detector signal, which is processed to calculate a physiological parameter indicative of the physiological reaction.

Systems and methods are provided for performing OCT vibrography based on the synchronization of components of the OCT vibrography system. An A-scan trigger is employed to synchronize the operation of the scanning subsystem that scans the sample beam and an acoustic stimulus source that generates an acoustic stimulus for vibrographic measurements. The acoustic stimulus source is controlled such that when the scanning subsystem dwells on an imaging line selected for vibrography measurements, the acoustic stimulus is generated over a plurality of A-scans and the phase of the acoustic stimulus is locked to the A-scan trigger, such that the phase of the acoustic stimulus is incrementally modified with each A-scan. The accumulation of the acoustic phase is therefore synchronized to the A-scan trigger. The synchronization, providing synchronized acoustic phase evolution during each acoustic phase waveform cycle, permits the use of the OCT vibrography system for simultaneous anatomical and functional imaging.

An excitation force (internal or external) and phase-sensitive optical coherence elastography (OCE) system, used in conjunction with a data analyzing algorithm, is capable of measuring and quantifying biomechanical parameters of tissues in situ and in vivo. The method was approbated and demonstrated on an example of the system that combines a pulsed ultrasound system capable of producing an acoustic radiation force on the crystalline lens surface and a phase-sensitive optical coherence tomography (OCT) system for measuring the lens displacement caused by the acoustic radiation force. The method allows noninvasive and nondestructive quantification of tissue mechanical properties. The noninvasive measurement method also utilizes phase-stabilized swept source optical coherence elastography (PhS-SSOCE) to distinguish between tissue stiffness, such as that attributable to disease, and effects on measured stiffness that result from external factors, such as pressure applied to the tissue. Preferably, the method is used to detect tissue stiffness and to evaluate the presence of its stiffness even if it is affected by other factors such as intraocular pressure (TOP) in the case of cornea, sclera, or the lens. This noninvasive method can evaluate the biomechanical properties of the tissues in vivo for detecting the onset and progression of degenerative or other diseases (such as keratoconus).

Among the various aspects of the present disclosure is the provision of systems and methods of velocity-matched ultrasonic tagging in photoacoustic flowgraphy.

A vibration generating system (100) for elastography equipment and a control method thereof, elastography equipment, a method for controlling the vibration generating system (100) for elastography equipment, a method for operating the elastography equipment, and a corresponding computer-readable medium. The vibration generating system (100) for elastography equipment comprises: a control unit (1), a pressure source (2), a pressure regulating unit (3), and a vibration transmitting unit (4). The pressure regulating unit (3) is in fluidic communication with the pressure source (2) and the vibration transmitting unit (4), respectively. The vibration transmitting unit (4) is used to transmit vibration according to a pressure acting thereon. The control unit (1) is coupled with the pressure regulating unit (3). The control unit (1) is configured to obtain a control parameter by using a look-up table module (12) according to inputted elastography conditions, so as to control the pressure regulating unit (3).

A mechanical vibration source for a shear wave elastography system has a contact surface shaped to provide a point source of mechanical energy when striking a target surface of a medium. This point source usefully mitigates high frequency components and other artifacts in an induced shear wave. Other techniques may be used in combination with this mechanical energy source to improve shear wave elastography and facilitate miniaturization for deployment, e.g., within a handheld imaging device.

Systems and methods for accurate determination of the position of an anatomic part of a subject in robotic assisted image-based surgery, using an inertial measurement unit (IMU) to determine the position and orientation of the anatomical part of the subject. The intrinsic drift of the IMU, which would make the IMU position measurements inaccurate, can be reset to zero regularly, at points of time when the subject's body is stationary. This can be achieved when motion from the subject's breathing and from the heartbeat are essentially zero. Such positions occur respectively when the respiratory signal shows the position of the breathing cycle to be at the end of the expiration phase, and the heartbeat signal represents a time in the diastole period of the subject's electrocardiographic cycle. When these two signal moments coincide, the IMU is essentially stationary, and its drift reset to zero.

The present disclosure relates to a system and method for non-invasively determining NAFLD activity scores (NAS) in patients using mechanical properties determined through magnetic resonance elastography (MRE) imaging. The non-invasively determined NAS score is then used to diagnose NFALD and NASH patients.

A portable quantification apparatus for assessing joint accessory movement is disclosed in the present invention. The apparatus includes a reference unit, a movement unit, a sliding unit and a displacement sensor. The reference unit has a first probe and a first force sensor. The movement unit has a second probe and a second force sensor. The sliding unit is disposed between the reference unit and the movement unit which allows the movement unit to slide alongside with the reference unit. When a patient is under a test, the first probe is against one of two adjacent bones of a joint, while the second probe is against the other adjacent bone. The first force sensor and the second force sensor sense a first force and a second force applying to the reference unit and the movement unit respectively. The displacement sensor measures a relative movement of the movement unit over the reference unit.

Systems and methods are described for performing diagnostic procedures, such as vibrometric diagnostic procedures. An example system includes a handheld vibrometric device, a handheld controller, and a control and processing console. The handheld controller includes an input receiving mechanism for controlling the handheld vibrometric device and/or controlling a user interface generated by the console. The handheld controller is configured such that when the handheld vibrometric diagnostic device is supported by a first hand of an operator and the handheld controller is supported by a second hand of the operator, the input receiving mechanism is capable of being actuated by a digit of the second hand while maintaining support of the handheld controller by the second hand, in the absence of contact with the control and processing console and the handheld vibrometric diagnostic device, thereby facilitating control of the handheld vibrometric diagnostic device without mechanically perturbing the handheld vibrometric diagnostic device.