Browse our broad range of products and solutions in orthopaedics, spinal care, sports medicine
and neuroscience. Click here for our product and program spotlights.
The cranial cavity contains one of the most interesting hydrodynamic systems within the human body, one that has historically engaged the attention of both engineer and neurosurgeon in a search for a better method for treating hydrocephalus. Physicians have traditionally been limited when faced with choosing the right fixed pressure valve prior to implantation. Even if chosen correctly at the time of implantation, surgical revisions may be required as the patient's pathophysiology changes. Basically, the patient is forced to adapt to a fixed pressure valve. With the advent of the CODMAN® HAKIM® Programmable Valve System, neurosurgeons can pre-select one of 18 different pressure settings. HAKIM is a registered trademark of Hakim USA, LLC and is used under license by Codman & Shurtleff, Inc. After implantation, the valve can be adjusted non-invasively to adapt to changes in patient condition. That means surgeons are able to make precise pressure adjustments to help control intracranial pressure and ventricle size at any time.
Unlike classic silicone shunt systems which only give surgeons three pressure ranges to choose from, the CODMAN HAKIM Programmable Valve features 18 pressure ranges.
These ranges provide the surgeon with the ability to make subtle alterations to the opening pressure. Each adjustment can be made quickly and easily through the programmer interface. Its precise mechanical design yields repeatable, linear pressure-flow responses. The micrometer scale (1/1000 mm) programming motions and tightly calibrated spring tensions which give the valve its accuracy are derived from the same microtechnology employed by the Swiss watch industry.
The same miniature manufacturing processes which make the valve accurate also make it reliable. Only superior materials that can stand up to the conditions evident in patients with hydrocephalus are chosen. The parts are also completely biocompatible, with the low profile of both the full housing and micro-housing resulting in an unobtrusive implant.
Once assembled, the valves are tested five separate times prior to release to ensure they meet stringent performance standards.
It is acceptable to prime the valve by filling it with lint-free sterile saline or an appropriate antibiotic solution prior to implantation. If the valve housing includes SIPHONGUARD®, priming the system must be reduced to a rate of approximately .5cc/minute. The valve mechanism should be placed over a bony region and not over an area with an excessive amount of soft tissue. The valve could become embedded in the soft tissue, making it difficult to program postoperatively.
The valve must be oriented with the valve mechanism facing up towards the scalp and in the correct direction for CSF flow. The micro Valve, in-Line, and Right angle housings have a flat bottom that should rest against the skull, insuring that the mechanism is facing up.
POSTOPERATIVE PROGRAMMING (VPV™ SYSTEM #82-3192)
VALVE POSITIONING VERFICATION
Valve Adjustment: Implanted Valve Mode
1. Turn on the VPV™ Programmer Unit. The implanted valve icon illuminates.
2. The program unit beeps and the LED panel displays the following message: IMPLANTED VALVE PLEASE SELECT PRESSURE.
3. Press the appropriate setting selection key. The program unit beeps; the corresponding LEd illuminates. at the same time, the display changes to: IMPLANTED VALVE, POSITION TRANSMITTER HEAD, and PRESS START.
4. Palpate the scalp to locate the shunt and the implanted valve. Gently palpate the valve to locate the hard inlet portion, approximately 10mm long. Place your fingertip on the scalp directly over the inlet portion.
5. Part any hair with fingertips. Apply a pea-sized amount of ultrasound gel, approximately 2mm thick, to the patient's scalp.
Alternate method: apply ultrasound gel to the entire bottom surface of the center rod to a thickness of approximately 2mm.
6. Before placing transmitter on the scalp, ensure that the arrow on the transmitter is in line with the direction of fluid flow through the shunt.
7. Place the transmitter on the scalp so the center rod is directly over the hard inlet portion of the valve and the transmitter's feet contact the patient's scalp. The center rod may recede slightly and the gel will compress. Hold Transmitter in place until adjustment is complete (approximately 3 seconds). Eliminate or minimize ambient noise. Excessive noise can interfere with the acoustic monitoring process.
8. Press the transmitter's blue start button. The program unit beeps once and the LCD display changes to: ADJUSTING VALVE PLEASE WAIT.
9. During the adjustment, the setting selection keys light sequentially and the program unit emits a series of clicks until the selected setting command has been issued to the valve.
10. When the adjustment is complete (approximately 3 seconds), the program unit emits a long beep and the display changes to: ADJUSTMENT COMPLETE PRESS A KEY.
NOTE: If the acoustic monitoring feature did not receive an expected response, the program unit will emit three beeps and one of the two messages will be displayed.
REPEAT ADJUSTMENT or no SIGNAL REPEAT ADJUSTMENT PRESS A KEY.
After the "ADJUSTMENT COMPLETED" message is displayed press any key to clear. The LCD panel will change to the original message: IMPLANTED VALVE PLEASE SELECT PRESSURE.
The VPV Programmer provides confirmation of the valve adjustment without the need for radiographic imaging when the "ADJUSTMENT COMPLETED" message is displayed.
Programming the valve (PROGRAMMER #82-3190)
1. Turn on the programmer unit. The instruction light on the programmer panel will illuminate.
2. Choose the desired pressure on the programmer panel by pressing the corresponding raised button. The instruction light will come on.
3. Place the transmitter head over the valve such that the feet of the transmitter head straddle the valve mechanism and the arrows on the transmitter head align with the direction of CSF flow through the valve.
4. Press and release the start button on the transmitter head while holding the transmitter head in place. The instruction light illuminates and the pressure selector buttons sequentially light until the valve is finished being programmed.
5. Hold the transmitter head in place until the programmer beeps indicating that programming has been completed (approximately 3-5 seconds). The instruction light will briefly illuminate at the end of the programming cycle.
Magnets and an externally applied magnetic field generated by the programmer change the setting. The coded signal minimizes inadvertent programming by external fields. A marker within the valve lets you verify the setting by means of x-ray film or fluoroscopy.