Method and system for monitoring intracranial pressure

Abstract

Embodiments of the present invention relate to a system and method for monitoring intracranial pressure. Embodiments of the present invention include emitting an electromagnetic wavelength into forehead tissue of a patient and detecting characteristics of the electromagnetic wavelength after the electromagnetic wavelength has been scattered by the tissue. The characteristics may include variations in the electromagnetic wavelength corresponding to a pulse. Further, embodiments of the present invention include analyzing the variations to identify venous pulsations, and determining whether intracranial pressure is elevated in the patient based on a correlation between the venous pulsations and levels of intracranial pressure.

What is claimed is: 
     
         1 . A system for monitoring intracranial pressure, comprising:
 a sensor comprising:
 an emitter configured to emit at least one electromagnetic wavelength into tissue of a patient; and 
 a detector configured to detect the at least one electromagnetic wavelength after scattering by the tissue; 
   a monitor configured to be in electronic communication with the sensor, the monitor configured to analyze characteristics of the at least one detected electromagnetic wavelength to identify venous pulsations and to determine whether intracranial pressure is elevated in the patient based on correlation only between the venous pulsations and levels of intracranial pressure.   
     
     
         2 . The system of  claim 1 , comprising an adjustment measurement device configured to measure a level of adjustment corresponding to abolishment of identified venous pulsations. 
     
     
         3 . The system of  claim 1 , comprising:
 an inflatable headband; and   a pump configured to inflate the headband to increase pressure between the sensor and the tissue.   
     
     
         4 . The system of  claim 1 , comprising an adjustable head elevator configured to elevate the tissue with respect to the heart of the patient. 
     
     
         5 . The system of  claim 1 , wherein the monitor comprises a pressure mapping system. 
     
     
         6 . The system of  claim 1 , wherein the monitor comprises a pulse oximeter. 
     
     
         7 . A monitor for monitoring intracranial pressure, comprising:
 a processing device configured to:
 receive, via a sensor, a signal representative of at least one detected electromagnetic wavelength scattered by a forehead tissue of a patient; and 
 analyze characteristics of the signal to identify venous pulsations and to determine whether intracranial pressure is elevated in the patient based on a correlation only between the venous pulsations and levels of intracranial pressure. 
   
     
     
         8 . The monitor of  claim 7 , wherein the processing device is configured to receive an input representative of an amount of pressure applied to the forehead tissue of the patient that abolishes venous pulsations and to quantify the intracranial pressure based on the amount of pressure applied to the tissue. 
     
     
         9 . The monitor of  claim 8 , wherein the processing device is configured to cause an inflatable headband to adjust an amount of pressure applied to the forehead tissue of the patient. 
     
     
         10 . The monitor of  claim 7 , wherein the processing device is configured to receive an input representative of an angle or level of elevation of the forehead tissue relative to the heart of the patient that abolishes venous pulsations and to quantify the intracranial pressure based on the angle or level of elevation. 
     
     
         11 . The monitor of  claim 10 , wherein the processing device is configured to cause an adjustable head elevator to adjust the angle or level of elevation. 
     
     
         12 . The monitor of  claim 7 , wherein the characteristics include variations in the signal corresponding to a pulse. 
     
     
         13 . The monitor of  claim 12 , wherein the processing device is configured to analyze a shape of the variations to identify the venous pulsations based on a correlation between the shape and the venous pulsations. 
     
     
         14 . The monitor of  claim 7 , wherein the processing device is configured to analyze a phase difference between variations in at least two signals representative of detected electromagnetic wavelengths scattered by the forehead tissue of the patient to identify the venous pulsations based on a correlation between the phase difference and the venous pulsations. 
     
     
         15 . The monitor of  claim 14 , wherein each signal of the at least two signals is obtained from a different portion of the forehead tissue of the patient. 
     
     
         16 . The monitor of  claim 15 , wherein the processing device is configured to compare a ratio of the variations in a first signal of the at least two signals and the variations in a second signal of the at least two signals to identify the venous pulsations based on a correlation between the ratio and the venous pulsations. 
     
     
         17 . The monitor of  claim 7 , wherein the processing device is configured to receive at least two signals representative of detected electromagnetic wavelengths scattered by the forehead tissue of the patient, each signal of the at least two signals is obtained from a different portion of the forehead tissue of the patient, and the processing device is configured to identify the venous pulsations by comparing a first oxygen saturation estimate obtained from a first signal of the at least two signals and a second oxygen saturation estimate obtained from a second signal of the at least two signals. 
     
     
         18 . The monitor of  claim 7 , wherein the processing device is configured to receive an electrocardiogram (ECG) signal of the patient and to compare a phase difference between a pulse of the signal representative of at least one detected electromagnetic wavelength and the ECG signal to identify the venous pulsations. 
     
     
         19 . A monitor for monitoring intracranial pressure, comprising:
 a processing device configured to:
 receive, via a sensor, a signal representative of at least one detected electromagnetic wavelength scattered by a tissue of a patient; and 
 determine whether venous pulsations are present in the tissue based on the received signal; 
 if venous pulsations are present, cause adjustment of an adjustment measurement device until venous pulsations cease; and 
 determine whether intracranial pressure is elevated in the patient based on a correlation only between a level at which venous pulsations cease and a level of intracranial pressure. 
   
     
     
         20 . The monitor of  claim 19 , wherein the adjustment measurement device comprises a pressure sheet.