The NeuroControl VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) is a radiofrequency (RF) powered motor control neuroprosthesis or neurostimulation system that consists of both implanted and external components. The VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) delivers low levels of electrical stimulation to a spinal cord injured patient's intact sacral spinal nerve roots in order to elicit functional contraction of the muscles innervated by them. The VOCARE Bladder System consists of the following subsystems:
-The Implanted Components include the Implantable Receiver-Stimulator and Extradural Electrodes.
-The External Components include the External Controller, External Transmitter, External Cable, Transmitter Tester, Battery Charger and Power Cord.
-The Surgical Components include the Surgical Stimulator, Intradural Surgical Probe, Extradural Surgical Probe, Surgical Test Cable, and Silicone Adhesive.
The VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) is indicated for the treatment of patients who have clinically complete spinal cord lesions (ASIA Classification) with intact parasympathetic innervation of the bladder and are skeletally mature and neurologically stable, to provide urination on demand and to reduce post-void residual volumes of urine. Secondary intended use is to aid in bowel evacuation.
CONTRAINDICATIONS
The NeuroControl VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) is contraindicated for patients with the following characteristics:
-Poor or inadequate bladder reflexes
-Active or recurrent pressure ulcers
-Active sepsis
-Implanted cardiac pacemaker
WARNINGS
The NeuroControl VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) may only be prescribed, implanted, or adjusted by clinicians who have been trained and certified in its implementation and use.
PRECAUTIONS
X-rays, Diagnostic Ultrasound: X-ray imaging, and diagnostic ultrasound have not been reported to affect the function of the Implantable Receiver-Stimulator or Extradural Electrodes. However, the implantable components may obscure the view of other anatomic structures.
MRI: Testing of the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) in a 1.5-Tesla scanner with a maximum spatial gradient of 450 gauss/cm or less, exposed to an average Specific Absorption Rate (SAR) of 1.1 W/kg, for a 30 minute duration resulted in localized temperature rises up to 5.5?C in a gel phantom (without blood flow) and translational force less than that of a 12 gram mass and torque of 0.47 N-cm (less than that produced by the weight of the device).
A patient with a VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) may undergo an MR procedure using a shielded or unshielded MR system with a static magnetic field of 1.5-Tesla only and a maximum spatial gradient of 450 gauss/cm or less.
The implantable components may obscure the view of other nearby anatomic structures. Artifact size is dependent on variety of factors including the type of pulse sequence used for imaging (e.g. larger for gradient echo pulse sequences and smaller for spin echo and fast spin echo pulse sequences), the direction of the frequency encoding, and the size of the field of view used for imaging. The use of non-standard scanning modes to minimize image artifact or improve visibility should be applied with caution and with the Specific Absorption Rate (SAR) not to exceed an average of 1.1 W/kg and gradient magnetic fields no greater than 20 Tesla/sec.
The use of Transmit RF Coils other than the scanner's Body RF Coil or a Head RF Coil is prohibited. Testing of the function of each electrode should be conducted prior to MRI scanning to ensure no leads are broken. Do not expose patients to MRI if any lead is broken or if integrity cannot be established as excessive heating may result in a broken lead. Patients should be advised to empty their bladder or bowel prior to MRI scanning as a precaution.
The external components of the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) must be removed prior to MRI scanning. Patients must be continuously observed during the MRI procedure and instructed to report any unusual sensations (e.g., warming, burning, or neuromuscular stimulation). Scanning must be discontinued immediately if any unusual sensation occurs. Contact NeuroControl Corporation or Finetech-Brindley for additional information.
Therapeutic Ultrasound, Therapeutic Diathermy, and Microwave Therapy: Therapeutic ultrasound, therapeutic diathermy, and microwave therapy should not be performed over the area of the Implantable Receiver-Stimulator or Extradural Electrodes as it may damage the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare).
Electrocautery: Do not touch the Implantable Components of the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) with electrocautery instruments. Do not use electrocautery within 1 cm of the metal electrode contacts.
Antibiotic Prophylaxis: Standard antibiotic prophylaxis for patients with an implant should be utilized to protect the patient when invasive procedures (e.g., oral surgery) are performed.
Drug Interactions: Anticholinergic medications, or other medications which reduce the contraction of smooth muscle, may reduce the strength of bladder contraction achieved using the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare).
Anticholinergic medications should be discontinued at least three days prior to evaluating patients for the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) and prior to implantation surgery so that bladder reflexes and response to electrical stimulation can be accurately evaluated. In addition, long-acting neuromuscular blocking agents must not be used during surgery.
Prior procedures (such as bladder neck surgery or bladder augmentation) or conditions (such as severe urethral damage, stricture, or erosion) may affect patient suitability for the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) or clinical outcome. Patients with bladder augmentation may not be candidates for this procedure unless they can still achieve appropriate bladder pressures through reflex contractions. Patients should be thoroughly evaluated and counseled regarding the effect of any prior procedures or conditions.
Post-operative incontinence may occur following posterior rhizotomy, which is typically performed in conjunction with implantation of the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare). While rhizotomy generally abolishes reflex incontinence, some patients may still experience stress incontinence. Patients should be evaluated for open bladder neck pre-operatively and counseled regarding the factors that may increase the risk of stress incontinence.
Bowel motility may be affected by the rhizotomy procedure and by use of the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare). Patients should be advised that the rhizotomy may decrease the response to suppositories and digital stimulation of the rectum. Conversely, use of the VOCARE Bladder System may increase bowel motility. Patients may need to adjust the frequency and/or method of their bowel management routine postoperatively.
The rhizotomy procedure typically performed in conjunction with implantation of the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) may cause loss of erectile function and ejaculation in men who had these responses before surgery.
Spinal instability may result from the laminectomies required during implantation and rhizotomy surgery. Patients should be evaluated carefully for added risk factors, such as significant osteoporosis or scoliosis.
Studies have not been conducted on the use of the NeuroControl VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) in pregnant women.
Post-operatively, the patient should be advised to check the condition of his or her skin over the VOCARE Bladder System Receiver-Stimulator and leads daily for signs of redness, swelling, or breakdown. If skin breakdown becomes apparent, patients should contact their clinician immediately. The clinician should treat the infection aggressively, taking into consideration the extra risk presented by the presence of the implanted materials.
Unintended Stimulation: While there have been no reports of VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) activation or malfunction due to electromagnetic interference (such as from retail anti-theft detectors, airport metal detectors, or other electronic devices) testing has not been conducted to rule out the possibility of this occurring. Patients should be advised to notify their clinician if they experience unintended stimulation when the VOCARE Bladder System is not in use. If possible, patients should note when and where the stimulation occurred.
Keep it dry: The user should avoid getting the external components, cables, and attachments of the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) wet.
-The patient and caregiver should be advised to inspect the external cables and connectors daily for fraying or damage and replace components when necessary.
-To avoid possible interference, patients with electric wheelchairs should be advised to turn off their wheelchair controller prior to turning on the VOCARE Bladder System External Controller.
-External Defibrillation: The effect of external defibrillation on the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) is unknown.
-Patients should be advised to turn off the VOCARE Bladder System External Controller when not in use. The External Transmitter can become hot if the VOCARE Bladder System/Finetech-Brindley Bladder System (Vocare) is left on for extended periods of time.
Excerpted with permission from VOCARE Bladder System Implantable Functional Neuromuscular Stimulator, NeuroControl Corporation, Valley View, OH and Finetech-Brindley Bladder System (Vocare)
For this device, MRI healthcare professionals are advised to contact the manufacturer to ensure that the latest safety information is obtained and carefully followed in order to ensure patient safety relative to the use of an MR procedure.
REFERENCE
http://www.finetech-medical.co.uk/ |