US4147161A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Intracranial pressure monitoring method and system
Assignee: CLINICAL ENGR LABS Ltd
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Filing: 1977-08-25
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Granted: 1979-04-03
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Expires: 1997-08-25
Abstract
Abstract System for measuring or monitoring the intracranial pressure which comprises a non-elastic detecting pouch to be inserted into the space between the skull and the cerebrum, a flexible tube connected to the pouch, a device for supplying a liquid into the pouch through the flexible tube and a device for measuring the pressure of the liquid in the pouch. When the pressure of the liquid reaches the intracranial pressure, the curve showing relation between liquid pressure vs. pouch volume flattens. Thus, by measuring the pressure of the flattened region, intracranial pressure may be determined.
Inventors
- 👤 Jun Ikebe
- 👤 Yoriaki Kumagai
- 👤 Kintomo Takakura
- 👤 Michio Ohta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 19:38
CPC Classifications
A; A61; A61B; A61B5/00; A61B5/03; A61B5/031
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
83 words
System for measuring intracranial pressure comprising a pouch consisting of a soft material which is non-elastic within the range of intracranial pressure, said pouch being of a size so as to allow its insertion between the skull and the cerebrum, said pouch being filled with a liquid for detecting the intracranial pressure, means for insuring no inflow and outflow displacement of the liquid in the pouch, and means for measuring the pressure of the liquid in said pouch, thereby detecting the intracranial pressure.
Claim 2
Dependent Claim
83 words
System for measuring intracranial pressure comprising a pouch consisting of a soft material which is non-elastic within the range of intracranial pressure, said pouch being of a size so as to allow its insertion between the skull and the cerebrum, said pouch being filled with a liquid for detecting the intracranial pressure, means for insuring no inflow and outflow displacement of the liquid in the pouch, and means for measuring the pressure of the liquid in said pouch, thereby detecting the intracranial pressure.
Claim 3
Dependent Claim
47 words
System for measuring intracranial pressure in accordance with claim 1 wherein said pouch has a flat surface constituting means for flatly contacting the dura mater when said pouch is in the space between the skull and dura mater with a sufficient volume of liquid in the pouch.
Claim 4
Dependent Claim
47 words
System for measuring intracranial pressure as set forth in claim 2, wherein the volume of the liquid in the pouch is in a flat region of the curve of detected pressure of the liquid vs. volume in the pouch, said detected pressure substantially equaling the intracranial pressure.
Claim 5
Dependent Claim
124 words
System for measuring intracranial pressure comprising a pouch consisting of a material which is non-elastic within the range of intracranial pressure for detecting the intracranial pressure, said pouch being of a size so as to allow its insertion between the skull and the cerebrum, a flexible tube connected to said pouch, means for supplying or discharging a liquid into or form said pouch through said tube, respectively, valve means for insuring no inflow and outflow displacement of the liquid in the pouch after supplying and during a measurement of the pressure thereof, and means connected to said tube for measuring the pressure of the liquid in said pouch and thereby detecting the intracranial pressure, said liquid having density equal to the mean cerebral density.
Claim 6
Dependent Claim
124 words
System for measuring intracranial pressure comprising a pouch consisting of a material which is non-elastic within the range of intracranial pressure for detecting the intracranial pressure, said pouch being of a size so as to allow its insertion between the skull and the cerebrum, a flexible tube connected to said pouch, means for supplying or discharging a liquid into or form said pouch through said tube, respectively, valve means for insuring no inflow and outflow displacement of the liquid in the pouch after supplying and during a measurement of the pressure thereof, and means connected to said tube for measuring the pressure of the liquid in said pouch and thereby detecting the intracranial pressure, said liquid having density equal to the mean cerebral density.
Claim 7
Dependent Claim
103 words
System for measuring intracranial pressure comprising a non-elastic pouch for detecting the intracranial pressure, means for supplying or discharging a liquid into or from said pouch, means for measuring the pressure of the liquid in said pouch, means for transforming said pressure of the liquid into an electrical signal, means for delaying said electrical signal for a predetermined period, means for comparing said electrical signal with said delayed electrical signal for emanating an output signal when difference between both electrical signals reaches to a predetermined small value, and means for stopping the supply or discharge of the liquid according to said output signal.
Claim 8
Dependent Claim
103 words
System for measuring intracranial pressure comprising a non-elastic pouch for detecting the intracranial pressure, means for supplying or discharging a liquid into or from said pouch, means for measuring the pressure of the liquid in said pouch, means for transforming said pressure of the liquid into an electrical signal, means for delaying said electrical signal for a predetermined period, means for comparing said electrical signal with said delayed electrical signal for emanating an output signal when difference between both electrical signals reaches to a predetermined small value, and means for stopping the supply or discharge of the liquid according to said output signal.
Claim 9
Independent Claim
100 words
A method for measuring intracranial pressure comprising inserting a flat pouch consisting of a non-elastic material into the space between the skull and the cerebrum through a cut portion of the skull, with a flexible tube communicating with the pouch extending through the cut portion in the skull, supplying a liquid into the pouch through the flexible tube until a volume of liquid in the pouch is in a region where the detected pressure of the liquid in the pouch substantially equals the intracranial pressure, and detecting the pressure of the liquid in the pouch, thereby determining the intracranial pressure.
Claim 10
Independent Claim
100 words
A method for measuring intracranial pressure comprising inserting a flat pouch consisting of a non-elastic material into the space between the skull and the cerebrum through a cut portion of the skull, with a flexible tube communicating with the pouch extending through the cut portion in the skull, supplying a liquid into the pouch through the flexible tube until a volume of liquid in the pouch is in a region where the detected pressure of the liquid in the pouch substantially equals the intracranial pressure, and detecting the pressure of the liquid in the pouch, thereby determining the intracranial pressure.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-04-02 | 1982-10-02 | 1983-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-04-02 | 1986-10-02 | 1987-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-04-02 | 1990-10-02 | 1991-04-03 | $7700.00 | Window Closed / Lapsed |