JPH02193674A - Valve for hydrocephalus - Google Patents

Abstract

PURPOSE: To decrease pressure of the fluid that reaches an excessive level by installing a pressure control valve equipped with a coil spring placed between the control valve body and a ball to control passing of fluid that energizes the ball to a valve seat and passes through the entrance of the control valve. CONSTITUTION: A housing 30 forms an inner chamber that has an entrance and an exit of a fluid each communicating with a ventricle and a drainage catheter. A detention valve 32 is placed at the end of the entrance and the a stainless steel made valve body 34 equipped with an entrance channel 36, which continues to a conical valve seat 38. The valve 32 works as a check valve and does not significantly confine fluid passage to a valve unit 16. However, the valve crushes protein solid brought by cerebrospinal fluid that flows into the valve unit 16. Fluid pressure of the cerebrospinal fluid is restrained by a pressure control valve 50 at the entrance or downstream of the check valve 32.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention This invention relates to cerebral spinal fluid drainage systems for relieving fluid pressures that reach excessive levels within the brain.

■1 [Technique] Hakim's US Patent No. 3,288. ], 42 and 3,
No. 527,226 relates to a catheter system for relieving pressure generated within the brain. These patents disclose systems for continuously controlling the drainage of cerebrospinal fluid from the brain and releasing cough fluid into the body. As seen most clearly in Figures 1 and 3 of the '226 patent to I(akiw),
To evacuate fluid from the brain, the process utilizes a valve unit having respective inlet and outlet valves. This allows the valve unit to be used as a pump to help open clogged drainage catheters.

'The two valves in the 226% valve unit are the same. They use a wave or serpentine spring to bias the captured ball against the fluid inlet seat of the valve. Experience with the valve unit shown in the '226 patent indicates that it is difficult to control the pressure at which fluid exits the brain using such a valve.

Each pressure relief system must be evaluated before being implanted in a patient, as different pressures are selected for different patients depending on their individual needs. If the valve pressure fluctuates from its rated value, fluid pressure can rise or fall to dangerous levels. The valve system for ventricular shunting is published in “C
ordisIntegral 5hunt Syst
em", which publication is hereby incorporated by reference, in which the valve unit discussed in the '226 prior art patent, supra. A second unit, characterized as a pediatric Hakim mechanism, is also disclosed in the Cordts publication. This unit is also designed to control the pressure of fluid flowing from the brain to the drainage site. It includes two valves mounted within the valve housing.The two valves in the pediatric unit provide more uniform regulation of fluid pressure through the cough unit I-.

Both valves in the pediatric liakim mechanism include a coiled spring captured between a valve body and a ball that selectively opens and closes against the valve seat. This pediatric valve mechanism is 3 m ffff adjustable, and experience with this pediatric unit suggests that more positive fluid pressure control is possible. However, there are perceived shortcomings in the functionality of the pediatric unit presented in the Copeys publication. High concentrations of proteins may be suspended in the fluid draining from the brain. This protein can clog passageways within the valve unit, resulting in unstable operation. If the clogged part is on the outlet side of the valve unit,
The pump action can successfully open the valve. However, if a blockage occurs in the inlet valve, the blockage will not be easily opened.

FIELD OF THE INVENTION The present invention relates to a system for relieving pressure generated within a patient's brain through the use of a catheter system that uses a valve unit having a hybrid structure. According to the invention, said valve unit has a housing forming an enclosure in which two valves are mounted, namely one inlet valve and a second outlet valve. The inlet valve is the one shown in the '226 patent.
It is similar in structure to the rakim valve. A wave spring biases a ball within the inlet valve seat. This first valve acts as a check valve allowing fluid to be pumped into the unit by passing pressure to the housing. The ball is pressed against the check valve seat, but is prevented from moving within the housing by the wave spring unit.

The valve unit outlet includes a valve having a valve body and a threaded insert that captures a spring between the body and a ball that seats opposite the body inlet. This is C0rdjs pediatric [
1akim mechanism.

The compression of the spring is adjusted during manufacture of the unit by rotation of the spring insert with respect to the valve body. This construction allows the pressure of the fluid passing through the valve unit to be quite tightly controlled without clogging the unit. Relatively low pressure control at the inlet section of the valve unit tends to break up suspended proteins to avoid clogging of the outlet valve.

These and other objects, benefits, and features of the invention will be better understood from the detailed description of the invention set forth with reference to preferred embodiments.

Figure-@a 10% plate size.

FIG. 1 is a schematic diagram disclosing a drainage system for relieving pressure within a patient's brain.

FIG. 2 is a cross-sectional view of a valve unit having an outlet connected to a catheter for draining fluid from the brain and, in addition, connecting to a catheter for draining fluid from the brain into a drainage site within the patient.

Turning to the drawings of 木田匪曵 - Sai艮 - Q 士嫡 - 憇, Figure 1 shows the four signs of lli; li 1
0 to the previously mentioned “Cordis Integral”
12 ventricular catheters implanted using the procedures described in the booklet titled '5hunt System'
1 illustrates a catheter system for evacuation of fluid. The ventricular catheter engages the anterior chamber 14. Front room 1
The fluid exiting the reservoir 4 or 5 enters a valve unit 16, which is disclosed in more detail in FIG.

Valve unit 16 includes an inlet 18 downstream from vestibule 14 .

Outlet 20 connects the brain to a drainage catheter 24 that drains cerebrospinal fluid into the patient's body. The surgical placement of this unit is C.
ordts Integral 5huntSys L
It can be seen in the em booklet.

In the system disclosed in FIG. 1, both catheters are connected together to the valve unit 16.

Ventricular catheter 12 is a radiopaque silicone elastomer ventricular catheter that has been treated with barium sulfate to enhance visualization of the catheter upon implantation. Drainage catheter 24 is also a silicone catheter that is substantially longer than the ventricular catheter for directing fluid drained from the brain through a valve unit and into a suitable drainage site, such as the patient's abdominal cavity or the right atrium of the heart. Consists of an elastomer catheter.

Valve unit 16 is housed within a silicone elastomer housing 30 having a cylindrical outer wall connected to the ventricle and drainage catheter by known techniques. One technique for connecting housing 30 to a catheter is an adhesive that bonds the catheter and housing 30 together.

Housing 30 defines an interior chamber having inlet and outlet ends in fluid communication with the ventricles and the drainage catheter, respectively. A check valve 32 is located at the inlet end of the interior chamber and includes: 1. It includes a stainless steel valve body 34 with an inlet channel 36 leading through to a conical valve seat 38. Valve body 34 is supported within a stainless steel cylinder 39 that engages the interior of the housing and orients valve body 34 at L7. Fluid exiting the front chamber 14 enters the valve inlet 36 and passes through the conical valve seat 38 on the control of a ball held within the valve seat by a serpentine spring 42. The spring is connected to the valve body 34 by a suitable connection at one end of the spring 42 remote from the valve seat 38. At the opposite end, spring 42 has a flat portion that engages ball 40 and holds it in place.

Valve 32 acts as a check valve and does not significantly restrict fluid passage into the housing of valve unit 16. However, it disrupts protein solids carried by the cerebral spinal fluid entering the valve unit 16.

Downstream from the inlet or check valve 32, a pressure control valve 50 regulates the fluid pressure of cerebrospinal fluid leaving the unit 16. Valve 5
0 has a stainless steel tubular valve body member 52 and a stainless steel threaded insert 54 that threadably engages in a manner that defines the pressure of fluid exiting the valve. insert 5
4 has a stepped inner diameter forming a circular ridge. The outer valve body tube 52 extends axially along the valve unit;
and includes a conical valve seat 56 and an inlet 58.

Ball 60 is biased toward valve seat 56 by a coil spring 62 captured between ridge 64 of insert 54 and valve seat 56 formed by outer member 52 . By adjusting the length between the ball 60 and the ridge 64 that engages the spring 62, the coil spring 6
The force applied by 2 can be summarized as follows. Before inserting the valve 50 into the housing 30, the valve body member 52
and insert 54 are rotated relative to each other to adjust the spring compression force to the desired value. Fluid entering the check valve 32 passes through the housing chamber of the valve unit 16 to the valve inlet 5 of the second valve 50. When the pressure reaches a value sufficient to overcome the force exerted by spring 62 and ball 60 on valve seat 56, fluid exits valve unit I6 by drainage catheter 24. The two valve balls 40.60 are made of synthetically produced ruby. Spring 42,6
2 and the valve body 34.52.54 are stainless steel.

The inlet valve essentially acts as a reflux valve so that fluid exiting the brain and anterior chamber (FIG. 1) enters the housing 30 (FIG. 2) through the inlet valve 32 and is controlled by adjustment of the outlet valve 50. It exits the valve unit 16 in the same manner. Passage of fluid through inlet valve 32, however, tends to fracture proteins carried in suspension by the fluid, resulting in reliable trouble-free flow of fluid through second valve 50.

When the valve unit 16 becomes clogged with protein deposited on the outlet valve 50, the unit can be pumped by applying pressure to the flexible housing 30, as is well known in the art.

Such pressure closes the check valve 32 but forces the trapped fluid and protein through the outlet valve 50 at a pressure high enough to open the valve.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic illustration of a drainage system for relieving pressure in the brain of a patient, and FIG. 2 is a cross-sectional view of a valve unit of the invention connected to a catheter. 10 is a brain, 12 is a ventricular catheter, 14 is an anterior chamber, 24 is a drainage catheter, 30 is a housing, 32 is an inlet valve, 5
0 is the outlet valve.

Claims (3)

[Claims] (1) A valve device used to drain cerebrospinal fluid from the brain at controlled pressure, comprising: a) an elongated housing defining an interior chamber having an inlet end and an outlet end, the inlet end comprising: b) the housing is in fluid communication with a catheter for directing fluid from the brain, the outlet end being in fluid communication with a catheter for directing the fluid to a drainage location in the patient; b) an inlet end of the interior chamber; an inlet valve, an inlet valve body forming a valve seat, a ball that moves towards and away from the valve seat in response to fluid passing through the inlet valve, connected to the inlet valve body at one end and at the opposite end; c) an inlet valve having a ball-engaging surface at the inlet valve and an inlet valve spring that tends to retain the ball against the valve seat; c) disposed in the interior chamber downstream from the inlet valve; a pressure control valve body having an inlet with a valve seat, a ball proportionately sized to close the control valve seat, and biasing the ball against the valve seat to permit passage of fluid through the control valve inlet; Valve device characterized in that it comprises a pressure control valve with a coil spring captured between the ball and the control valve body for adjustment. (2) The valve device according to item 1, wherein the inlet valve spring is a serpentine spring. (3) a ventricular catheter capable of being implanted within the brain at one end and connected at an opposite end to an inlet end of the elongate housing, and one end connected to an outlet end of the housing and disposed at a fluid evacuation site; the first or second section further comprising a drainage catheter having an opposite end to obtain a drainage catheter;
Section valve device.