摘要:
An apparatus and method for simulating human ophthalmic artery for testing of ultrasound devices is disclosed, whereby two chambers are provided and are capable of being independently pressurized, one representing the intra-cranial space and the other representing extra-cranial space, and whereby a tube running through both chambers is provided, simulating the course of the ophthalmic artery and capable of being pressurized to stimulate arterial pressure. The apparatus is operated by pressuring both chambers, and pumping a blood-imitating fluid through the vessel in a pulsatile manner.
摘要:
An apparatus and method for simulating human ophthalmic artery for testing of ultrasound devices is disclosed, whereby two chambers are provided and are capable of being independently pressurized, one representing the intra-cranial space and the other representing extra-cranial space, and whereby a tube running through both chambers is provided, simulating the course of the ophthalmic artery and capable of being pressurized to stimulate arterial pressure. The apparatus is operated by pressuring both chambers, and pumping a blood-imitating fluid through the vessel in a pulsatile manner.
摘要:
A method and apparatus for obtaining the absolute value of intracranial pressure in a non-invasive manner is described by using an ultrasonic Doppler measuring device which detects the intracranial and extracranial blood flow velocities of the intracranial and extracranial segments of the ophthalmic artery. The eye in which the blood flow is monitored is subjected to an external pressure, sufficient to equalize the intracranial and extracranial angle-independent blood flow factors calculated from the intracranial velocity signal and extracranial velocity signal. The absolute value of the intracranial pressure is identified as that external pressure at which such equalization occur
摘要:
A method and apparatus for obtaining the absolute value of intracranial pressure in a non-invasive manner is described by using an ultrasonic Doppler measuring device which detects the intracranial and extracranial blood flow velocities of the intracranial and extracranial segments of the ophthalmic artery. The eye in which the blood flow is monitored is subjected to an external pressure, sufficient to equalize the intracranial and extracranial angle-independent blood flow factors calculated from the intracranial velocity signal and extracranial velocity signal. The absolute value of the intracranial pressure is identified as that external pressure at which such equalization occurs.
摘要:
A non-invasive method for continuous real-time monitoring of cerebrovascular blood flow autoregulation state includes simultaneous non-invasive monitoring of intracranial blood volume respiratory waves and lung volume respiratory waves, real-time decomposition of intracranial blood volume respiratory waves and lung volume respiratory waves into narrowband sinewave first harmonic components, determination therefrom of the phase shift between intracranial blood volume respiratory wave and lung volume respiratory wave first harmonics' and derivation of cerebrovascular autoregulation state from that phase shift value.
摘要:
A non-invasive method for monitoring of cerebrovascular blood flow autoregulation state includes sensing intracranial blood volume waves, filtering a slow wave, respiratory wave, and pulse wave informative components from said intracranial blood volume waves, filtering slow wave and respiratory wave reference components from the pulse wave envelope, calculating a first phase shift between said slow wave informative component and said slow wave reference component, calculating a second phase shift between said respiratory wave informative component and said respiratory wave reference component, and calculating the index of evaluation of the status of cerebral autoregulation state (ICAS) from said first phase shift and said second phase shift.
摘要:
A method and apparatus for continuously measuring the absolute intracranial pressure in a non-invasive manner is described by using an ultrasonic Doppler device which detects the pulsatility indexes of the blood flow inside the eye artery for both intracranial and extracranial eye artery portions. The eye in which the blood flow is monitored is subjected to a small pressure, sufficient to equalize the pulsatility index measurements of the internal and external portions of the eye artery. The pressure at which such equalization occurs is used as a reference for autocalibration of the apparatus so that continuous absolute intracranial pressure measurements may be taken over a particular sampling period.
摘要:
A non-invasive method for continuous real-time monitoring of cerebrovascular blood flow autoregulation state includes simultaneous non-invasive monitoring of intracranial blood volume respiratory waves and lung volume respiratory waves, real-time decomposition of intracranial blood volume respiratory waves and lung volume respiratory waves into narrowband sinewave first harmonic components, determination therefrom of the phase shift between intracranial blood volume respiratory wave and lung volume respiratory wave first harmonics' and derivation of cerebrovascular autoregulation state from that phase shift value.
摘要:
A method and apparatus for continuously measuring the absolute intracranial pressure in a non-invasive manner is described by using an ultrasonic Doppler device which detects the pulsatility indexes of the blood flow inside the eye artery for both intracranial and extracranial eye artery portions. The eye in which the blood flow is monitored is subjected to a small pressure, sufficient to equalize the pulsatility index measurements of the internal and external portions of the eye artery. The pressure at which such equalization occurs is used as a reference for autocalibration of the apparatus so that continuous absolute intracranial pressure measurements may be taken over a particular sampling period.
摘要:
A method and apparatus for continuously measuring the absolute intracranial pressure in a non-invasive manner is described by using an ultrasonic Doppler device which detects the pulsatility indexes of the blood flow inside the eye artery for both intracranial and extracranial eye artery portions. The eye in which the blood flow is monitored is subjected to a small pressure, sufficient to equalize the pulsatility index measurements of the internal and external portions of the eye artery. The pressure at which such equalization occurs is used as a reference for autocalibration of the apparatus so that continuous absolute intracranial pressure measurements may be taken over a particular sampling period.