摘要:
An ultrasonic method for indicating a characteristic of intracranial components' volume changes includes the transmission of broadband ultrasound from a transmitting transducer positioned on one side of a human head to a receiving transducer located on another side of the human head with decomposition of the received signal into narrowband components and determination therefrom of group delay, phase angle and attenuation as a basis for derivation of the characteristic of the intracranial media.
摘要:
An ultrasonic method for indicating a characteristic of intraparenchymal brain tissue includes the transmission of broadband ultrasound from a transmitting transducer positioned on one side of a patient's cranium to a receiving transducer located on another side of the cranium with decomposition of the received signal into narrowband components and determination therefrom of group delay, phase angle and attenuation as a basis for derivation of the characteristic of the intraparenchymal tissue within the cranium.
摘要:
An apparatus for measuring the intracranial pressure in a non-invasive manner is described by using an ultrasonic Doppler device which detects the velocities of the blood flow inside the optic artery for both intracranial and extracranium optic artery portions. The eye in which the blood flow is monitored is subjected to a small pressure, sufficient to equalize the blood flow measurements of the internal and external portions of the optic artery. The pressure at which such equalization occurs is found to be an acceptable indication of the intracranial pressure. Various devices are illustrated and used to enable either an automatic or manual intracranial pressure measurement.
摘要:
An ultrasonic method for indicating a characteristic of intracranial components' volume changes includes the transmission of broadband ultrasound from a transmitting transducer positioned on one side of a human head to a receiving transducer located on another side of the human head with decomposition of the received signal into narrowband components and determination therefrom of group delay, phase angle and attenuation as a basis for derivation of the characteristic of the intracranial media.
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 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:
An ultrasonic non-invasive technique is descried for deriving the time dependencies of characteristics of certain regions in the intracranium medium. Precise measurements of the transit travel times of acoustic pulses are made and processed to extract variable portions indicative of, for example, the pulsatility due to cardiac pulses of a basal artery or a cerebroventricle or the variation in the pressure of brain tissue, as well as changes in the cross-sectional dimension of the basal artery and ventricle. In one technique, the transit time variations attributable to cardiac pulses are extracted by processing higher harmonics in the frequency domain. Frequency and phase detection techniques are described.
摘要:
An apparatus and method for noninvasively measuring intracranial pressure of a subject using an ultrasound transducer. The transducer is used to measure arterial wall movement of an intracranial segment and an extracranial segment of the subject's ophthalmic artery as different external pressure forces are applied to the orbital area of the subject. When the waveforms of arterial wall movement between the intracranial segment and the extracranial segment are similar the intracranial pressure can be determined.
摘要:
A head frame for use in non-invasively determining the absolute value of intracranial pressure of a living body having a hard, flexible shield for covering the eye area of a patient. The shield has an inner surface and an outer transducer surface. An elastic film is sealed along its outer edge to the inner surface of the shield forming an expandable chamber. First and second connectors are located on the shield, permitting an inflow and outflow of pressurized liquid to the chamber. The elastic film expands inward toward the patient with an inflow of pressurized liquid, imparting a pressure against the patient's eye. An adjustable strap is attached to the shield for securing the head frame to the head of the patient.
摘要:
A device for obtaining an indication of the intracranial pressure of a living body includes a positional sensor which determines an initial position of an elastic biological object when the intracranial pressure within the living body is zero and which determines a subsequent position of the elastic biological object when the intracranial pressure within the living body is unknown but greater than zero. A pressure generator applies an external pressure to the elastic biological object, and a comparator compares the initial position with the subsequent position so as to identify the unknown intracranial pressure of the living body as that external pressure which causes the subsequent position to be equal to the initial position.