Abstract:
A wirelessly controlled inflatable medical implant system includes an external control module and an implantable module. The external control module may transmit wireless power and control signals, which are received by circuitry on a flexible printed circuit board in the implantable module. In response to the received signals, circuitry in the flexible printed circuit board may cause a motor and pump combination to transfer fluid from a reservoir in the implantable device, through tubing, and into inflatable medical implant located in the penis. The flexible printed circuit board, motor, and pump may be placed within the fluid reservoir, which provides a heat sink that prevents overheating of the implant.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to U.S. Provisional Application No. 62/220,593 filed on Sep. 18, 2015. The entire disclosure of the prior application is hereby incorporated by reference herein. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention is directed to an apparatus and method for treating erectile dysfunction, urinary and fecal incontinence, and other medical problems treated with inflatable medical implants. In particular, the apparatus includes a software application for setting and monitoring apparatus use parameters; an external controller which includes a power source, electronics for transdermal power transmission, display, control and communications and patient displays and controls. Specifically, the invention provides for transdermally controlled and powered implants including an isotonic fluid reservoir containing transdermal power reception circuitry, a flex circuit board housing integrated circuits and one or more rotary electric pumps that inflate and deflate one or more inflatable medical implants. 
       BACKGROUND OF THE INVENTION 
       [0003]    Existing erectile dysfunction implants typically use manually operated pumps and reversing switches implanted in the scrotum to transfer fluid back and forth between inflatable cylinders implanted in the penis and a fluid reservoir implanted in the abdomen. Some patients, particularly older people with arthritis, find it difficult to operate the pump and switch, and, therefore, may elect not to have the implant. 
         [0004]    Existing artificial urinary and anal sphincters implants use continuous passive pressure from a fluid reservoir implanted in the abdomen to inflate cuffs implanted around the urethra or anus. To operate, the patient depressurizes the cuff by manually depressing a pump, implanted in the scrotum for men and the labia for women, to transfer fluid from the cuff back to the reservoir. The cuff then repressurizes automatically to achieve continence. Like the penile implant, manual pump operation may be difficult, especially for women, where the pump&#39;s location makes operation difficult, may cause chronic discomfort and may limit activities such as bicycle riding. 
         [0005]    Additionally, current artificial sphincter lifespans may be limited by tissue atrophy. This common complication is likely caused by cuff dynamics, where constant pressure is applied to the biological structure over long time periods, and may be worsened by tissue frailty due to aging and cancer radiation treatments. 
         [0006]    More recent implant concepts may replace the manual pump with an electrically driven pump and reversing switches which may be controlled and powered from an external source. In operation, an external unit may send wireless control signals to an internal unit, which then activates the pump. In certain systems, the internal control unit and pump are powered by an internal source, such as batteries. In others, external power may be transmitted transdermally by close-coupled magnetic induction, which forms an air core electrical transformer. 
         [0007]    A recent erectile dysfunction implant concept replaces the manual pump with a transdermal close-coupled magnetic induction powered solenoid driven pump, analogous to a powered hypodermic syringe, to provide inflation and deflation. However, these devices may be limited because the solenoid pump implant is much larger than the manual pump implant&#39;s reservoir, as the solenoid must move out from the reservoir by as much as it moves in. Additionally, these devices may be MRI-unsafe because the solenoid&#39;s iron core may translate and rotate from MRI&#39;s magnetic fields, and may heat from the MRI&#39;s radio frequency (RF) field. 
         [0008]    Another recent implant concept for erectile dysfunction and urinary and fecal incontinence replaces the manual pump with an electric motor and pump or a nonmagnetic piezoelectric motor powered transdermally by close-coupled magnetic induction and external to internal control signals. These devices are limited because under leak conditions, the motor will run continuously until power is exhausted and the piezoelectric motor may produce limited pumping force at single digit efficiency resulting in slow operation and excess heating. Additionally, the coupling of the piezoelectric motor to the pump, complicated motor drive electronics and the use of powered valves may be volume intensive, of lower reliability and MRI-unsafe. 
         [0009]    Furthermore, these devices transmit power transdermally by close coupled magnetic induction, which forms an air core electrical transformer with its primary winding external to the patient and its secondary winding internal to the patient. Due to the low permeability of air and body tissue, magnetic flux linkages between these primary and secondary windings are not concentrated like they are in an iron core transformer. Therefore the implanted transformer secondary must be implanted in the dermis, a millimeter from the transformer&#39;s external primary placed over the skin, a physically and cosmetically uncomfortable situation. Additionally, the amount of transdermal power that can be safely transferred is limited due to heating caused by the primary winding&#39;s strong electric field, which results from needing to magnetically transmit power through air and tissue. 
         [0010]    Also, physician changing of preset inflatable implant pressures is an invasive procedure; they offer no implant performance monitoring by the patient or physician; they have no means of relieving cylinder or cuff pressure should the implant fail; they address only one dysfunction at a time; and they do not allow for implant performance analysis across many patients. 
         [0011]    What is needed is a compact, easy to operate apparatus that is programmable, MRI-conditional and can treat multiple dysfunctions with one implant. A device is needed that can transmit sufficient power and bidirectional communications signals over longer distances, relieve cylinder and cuff pressure upon implant failure, not invade the labia or scrotum, increase artificial sphincter lifespan, and allow analysis of data across patients. 
       SUMMARY OF THE INVENTION 
       [0012]    The present invention is directed to an apparatus and method for treating erectile dysfunction, urinary and fecal incontinence, and other medical problems treated with inflatable medical implants. The apparatus includes a Physician&#39;s Software Application, an External Controller, an implantable module including a Pump in Reservoir Implant, and an Inflatable Medical Implant. The physician may use the Physician&#39;s Software Application, executed on a computational device, to set, monitor and noninvasively change implant inflation parameters stored in the External Controller. It may also collect controller data from the physician&#39;s patients so trends in performance may be analyzed for determining settings and for scientific papers. Communications between the Physician&#39;s Software Application and the External Controller may be hardwired, such as USB, or wireless, such as Bluetooth, Wi-Fi or NFC. 
         [0013]    Once the External Controller is programmed by the physician, the patient may use pushbuttons and a touch screen to send power, control signals and settings transdermally to the Pump in Reservoir Implant to inflate or deflate one or more Inflatable Medical Implants. The External Controller may also be programmed to alleviate tissue atrophy due to constant cuff pressure by lowering cuff pressure at night when less pressure is needed in supine patients to achieve continence. 
         [0014]    The External Controller may operate with the Pump in Reservoir Implant using resonant wireless power technology transmission and bidirectional data transfer. A battery charging station, included with the External Controller, may provide direct current (DC) power to recharge the External Controller&#39;s rechargeable battery power source. The charging station may run on 110-220V, 50-60 Hz and 12V automobile battery power. 
         [0015]    Upon receiving a control signal and data from the External Controller, a MRI-conditional Pump in Reservoir Implant, located in the abdomen, may inflate or deflate one or more Inflatable Medical Implants. During use, it may send performance data, such as pressure readings, back to the External Controller for patient viewing and for storage for later analysis by the physician using the Physician&#39;s Software Application. 
         [0016]    The Pump in Reservoir Implant may contain isotonic fluid, electronics and multiple electrically driven pumps to inflate and deflate implants, such as penile cylinders or artificial urethra or sphincter cuffs, to treat erectile dysfunction in men, urinary and fecal incontinence in both men and women and other conditions. Upon reception of a control signal and power from the External Controller, the pumps may transfer isotonic fluid to and from the reservoir and one or more Inflatable Medical Implants for inflation and deflation. The amount of fluid transferred may be controlled by powering the pumps for a fixed number of rotations. 
         [0017]    The pumps may be operated by rotary electric motors, such as nonferrous 3-phase squirrel cage or synchronous motors. The motor′ power may be received transdermally from the External Controller via resonant power transfer. A resonant power receiver in the Pump in Reservoir Implant may receive and convert the transmitted power into stable DC power for use by a microprocessor and power amplifiers. The microprocessor may then generate a 3-phase signal and triple power amplifiers may then provide the 3-phase power to drive the motors. No power is stored internally in the Pump in Reservoir Implant. 
         [0018]    Pump in Reservoir Implant sensors may then monitor pumping operation for failures such as out of range pump speed, leaks, electrical shorts and high temperatures. Sensor data may include reservoir and Inflatable Medical Device pressure, pump speed, motor current and voltage and reservoir temperature. These data may also be sent back the External Controller for monitoring by the patient and for storage for later analysis by the physician. The physician may then noninvasively change inflation parameters by reprogramming the External Controller. 
         [0019]    The electronic components may be house on a coated, flexible printed circuit board. The flexible printed circuit board, electric motor and pump may be submerged within the fluid reservoir to provide a heat sink that prevents local overheating of the patient during operation and during MRI examination. 
         [0020]    One or more independently controlled pumps may be placed in the reservoir to treat multiple dysfunctions. The Pump in Reservoir Implant may be made from MRI-conditional material, such as a nonferrous electronics, motors and pumps. The implant may also be made with components that contain ferrous materials making it MRI-unsafe. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0021]      FIG. 1  is a diagram illustrating the invention&#39;s components. 
           [0022]      FIG. 2  is a bock diagram of the Physician&#39;s Software Application. 
           [0023]      FIG. 3A  is a block diagram representation of the components of the External Controller, and  FIG. 3B  is an illustration of an example External Controller. 
           [0024]      FIG. 4A  shows a diagram of the MRI-conditional Pump in Reservoir Implant operating a single Inflatable Medical Implant. 
           [0025]      FIG. 4B  shows a diagram the MRI-conditional Pump in Reservoir Implant operating three Inflatable Medical Implants. 
           [0026]      FIG. 5  shows diagrams of a nonferrous squirrel cage motor used in a finite element model. 
           [0027]      FIG. 6  shows the MRI-unsafe Pump in Reservoir Implant operating three Inflatable Medical Implants 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0028]    The present invention is directed to an apparatus and method for treating erectile dysfunction, urinary and fecal incontinence and other conditions treated by inflatable medical implants. As shown in  FIG. 1 , the apparatus includes a Physician&#39;s Software Application  101  which can run on computational devices  102 , and which allows the physician to program an External Controller  103  for use by patients. 
         [0029]    The patient, using the External Controller  103 , may then operate a Pump in Reservoir Implant  104  to inflate and deflate an Inflatable Medical Implant  106 . Sensors in the Pump in Reservoir Implant  104  report performance data for fault detection and back to the External Controller  103  for additional fault detection, viewing by the patient and for storage for later transmission to the Physician&#39;s Software Application  101  for use by the physician to noninvasively change inflation parameters and for statistical analysis across patients. 
         [0030]    The Physician&#39;s Software Application  101 , executed on a computing device  102 , such as a laptop, desktop, smartphone, or tablet, may allow the physician to set, monitor and noninvasively change implant inflation parameters stored in the External Controller  103  and then send them to the Pump in Reservoir Implant  104 . Inflation parameters may include number of pump revolutions, pump speed versus time and safety limits such as pressure and temperature. It may also collect data from multiple patients so trends in usage and performance may be analyzed for determining settings and for scientific papers. 
         [0031]    External Controller&#39;s  103  inflation data may originate from the physician, the apparatus provider and from apparatus performance data it receives from sensors placed in the apparatus, which may be stored in the External Controller  103  during each usage for later transmission to the application. When in range, such as during office visits or hospitalizations, the Physician&#39;s Software Application may transfer computer programs and data to the External Controller  103  using encrypted transmissions via wired and wireless channels such as USB, Bluetooth, Wi-Fi or NFC. These channels may also be used for the performance data stored in the External Controller  103 . All software may be updated from time to time by the apparatus provider over the internet 
         [0032]    A Pump in Reservoir Implant  104  is provided that receives power, control signals and data from the External Controller  103 , on command pumps isotonic fluid to inflate and deflate Inflatable Medical Implants  106 , and returns performance data to the patient and physician via the External Controller  103  and the Physician&#39;s Software Application  101 . The Pump in Reservoir Implant  104  may be inserted into the patient&#39;s abdomen and connected to the Inflatable Medical Implant  106  via Tubing  105  during a single surgery. It may contain more than one pump to treat multiple conditions. 
         [0033]    A block diagram of the software modules contained in the Physician&#39;s Software Application is shown in  FIG. 2 . The Implant Parameter module  201  may provide the physician with the capability to update External Controller  103  software, set inflation parameters and monitor operation of the implant. The physician may set the amount of fluid that the pump transfers at what speed for each operation during each time of day. For example, to increase artificial sphincters life, the physician may want to find the minimum amount of fluid to transfer, day and night, to achieve continence. Pump operating time and output pressure data may then be used to assist the physician in finding this minimum, and noninvasively adjust it over time, as tissue atrophies. 
         [0034]    Data from the Implant Parameter module  201  may be stored in an encrypted Patient Data Base module  202 . The Patient Data Base module  202  may store all the physician&#39;s implant patient data. An Analytics module  203  may provide the physician with the capability to study trends in patient data contained in the Patient Data Base  202 . Analysis may include looking at atrophy rates of artificial sphincter patients with specific devices, determining when a particular patient&#39;s cuff is about to fail, and warning of pumps and motors that are about to fail. An Executive module  204  may control and oversee the use of other modules by providing services such as such a logon, logoff and module selection. A Graphic User Interface, GUI, module  205  may provide the displays and controls for the physician to interface with the application&#39;s modules. A Communications module  206  may provide data transfer between the Implant Parameter module  201  and the External Controller  103 . A Security module  207  may provide data encryption and physician authentication. And, a Multi-Platform Interface  208  may provide application operation across different physician platforms with different screen sizes. 
         [0035]    An External Controller  103  is provided that interacts with and controls the Pump in Reservoir Implant  104 . The External Controller  103  may send power to the Pump in Reservoir Implant  104 , and may send data to and receive data from the Pump in Reservoir Implant  104 , thus allowing a patient to transdermally activate, control and power the Pump in Reservoir Implant  104 . 
         [0036]    On command from the patient, the External Controller  103  may wirelessly send control signals, power and inflation parameters to the Pump in Reservoir Implant  104  for its operation. It may receive reservoir and pump pressure data, pump speed, motor current and voltage, reservoir temperature, or usage data from the Pump in Reservoir Implant  104 . Power transmission may be by AirFuel” or “Qi” compliant standards and communication may be by “AirFuel” or “Qi” compliant, Bluetooth or Wi-Fi standards. 
         [0037]      FIG. 3A  is a block diagram representation of the components of the External Controller, and  FIG. 3B  shows an illustration of an example External Controller. When not in use, the External Controller  301  may sit in a Battery Charging Station  302 . The station may provide DC power to charge the External Controller&#39;s rechargeable batteries  304 . Overcurrent, short circuit and over temperature protection may be provided. The Battery Charging Station  302  may be powered from 110-220 V, 50-60 Hz or 12 VDC car battery sources. When a Power Button  303  is pressed, the Rechargeable Battery Power Source  304  may supply power to the External Controller to wake up its functions and await commands from the patient via patient controls  305  or from the physician via a Communications Port  306 . The External Controller&#39;s Rechargeable Battery Power Source  304  may include a rechargeable battery such as Lithium Ion or NiMH. 
         [0038]    Patient controls  305  may be provided via push buttons, a touch screen or both. They may include “On, Off, Inflate and Deflate.” Multiple controls may be provided for implants operating more than one Inflatable Medical Device  106 . Upon activating any control, an interrupt may be sent to a Microprocessor  307  which contains a nonvolatile memory storing an executable computer program, physician&#39;s settings, such as number of urinary cuff motor rotations for day and for night use, and implant usage data. A software interrupt service routine then determines which control was activated and what action to take. Should the action require operation of the Pump in Reservoir Implant  104 , control signals and the appropriate data, such as pump rotations, are sent to the Power transmitting Unit  308  over a data bus, such as an I 2 C serial interface. 
         [0039]    The Microprocessor  307  may be programmed through the Physician&#39;s Software Application  101  located on the physician&#39;s computational device  102 . The Microprocessor  307  may be programmed to stop operation if the signal is lost or preset safety parameters, such as pressure, pump speed range, motor current and voltage and temperature are exceeded. The Microprocessor  307  may turn off power if no activation signals are received after a preset time interval. Upon reception of a control signal and data from the Microprocessor  307 , a Power Transmitting Unit, PTU,  308  may generate and transmit power and data transdermally via a Transmitting Resonator  309  to the Pump in Reservoir Implant  104 , and may operate at the 6.78 MHz “AirFuel Alliance” resonance specified frequency, a decade below the 63.87 MHz RF transmitter frequency of 1.5-tesla MRI machines. 
         [0040]    Additionally, encrypted control signals and data may be sent to the Pump in Reservoir Implant  104  wirelessly via Bluetooth, Wi-Fi or NFC. Also, the wireless communications, along with the Communications Port  306 , may be used to communicate with the Physician&#39;s Software Application  101 . 
         [0041]    The Transmitter Resonator  309  may include a coiled wire inductor and a series capacitor whose combination may resonate at 6.78 MHz. A wire coil may be located in both the External Controller Case  301  and in the Transmitter Resonator Pad  310 , which may be provided to make it easy for the patient hold the wire coil on the skin over the implant. The pad and the case are connected via a plugin Cable  305 . Plugging the Cable  305  into the case  301  may disconnect the case&#39;s coil. For operation, the patient may place the case  301  or the pad  310  on the skin over the Pump in Reservoir Implant  104 , and then operate the desired control  305 . Resonant technology may be used to transmit power because it produces an evanescent electromagnetic field, as opposed to a close-coupled magnetic field, for longer distance, higher power operation. The Transmitter Resonator  309  may transmit power to the implant with up to 1-inch separation between the resonator&#39;s wire coil and the implant. Other resonant power technologies, such as Wireless Power Consortium “Qi” compliant devices, may also be used. 
         [0042]    Performance and safety data from the Pump in Reservoir Implant  104  may be sent back to a Display  311  via the Transmitter Resonator  309 , the Power Transmitting Unit  308  and the Microprocessor  307  for viewing by the patient and physician. It may also be recorded in the Microprocessor  307  for later use by the physician. In particular, time-varying reservoir and Inflatable Medical Device  106  pressure, pump speed, motor current and voltage and reservoir temperature may be received. 
         [0043]      FIG. 3B  provides an illustration of an Example External Controller. As shown, the External Controller may include a case  301  with a touch screen and control buttons. The buttons are set to provide On and Off control of three pumps in one implant. The center button  303  is a Power On and Off button. For an implant with only one motor, three buttons may be provided. The External Controller may also have a lanyard  312  which may allow patients to hang the controller from the neck while in use, such as between starting and stopping urination or defecation. 
         [0044]    Details of the Pump in Reservoir Implant  104  operating a single Inflatable Medical Implant  106  are shown in  FIG. 4A .  FIG. 4B  shows a Pump in Reservoir Implant  104  operating three Inflatable Medical Implants  417 ,  418 , and  419 . The Pump in Reservoir Implant may be MRI-conditional, with components that would not cause problems when introduced into an MRI machine. The implant may also be implemented with components,  FIG. 6 , which may contain MRI-unsafe materials. 
         [0045]    As shown in  FIGS. 4A, 4B and 6 , both implementations may power any combination of penile cylinders, urinary and anal cuffs, and other inflatable medical implants. Since cuffs require less than 1/10 th  the amount of fluid transfer than the cylinders, smaller combinations of pumps and reservoirs may be used for cuff only applications. In the MRI-conditional implementation,  FIGS. 4A and 4B , the electronics, motors and pumps may be made from materials that do not contain ferrous materials (magnetic field pull and torque) or long electrical conductors (RF field heating). 
         [0046]    In  FIG. 4A , a Reservoir Case  401  may contain a transdermal power Receiver Resonator  403 , nonferrous integrated circuits mounted on a flex circuit board, a nonferrous 3-Phase Squirrel Cage Motor  409 , a Planetary Reduction Gear  410  and a Reversible Pump  411  all submerged in an Isotonic Fluid  402 , such as normal saline solution. The isotonic fluid may be the operating fluid, provide a heat sink for the electronics, motor and pump, and not change the patient&#39;s local electrolytic balance should leakage occur. The Reservoir Case  401  may also have a biologically inert outer wall with an insulating material, such as Nomex, molded into the wall to reduce heat transfer rate from the isotonic fluid to the patient in this low duty cycle application. The empty reservoir may be folded into a cylindrical shape to ease insertion by the surgeon. The surgeon may then fill the Reservoir Case  401  with the Isotonic Fluid  402  through a Fill Port  416  after inserting it into the patient&#39;s abdomen. The Receive Resonator  403  may receive RF energy transdermally from the Transmitting Resonator  309 . Additionally, it may be used as the antenna for bidirectional communication with the External Controller  103 . 
         [0047]    The Receive Resonator  403  may include a resonant circuit made up of a wire coil inductor and series capacitor, which may resonate at 6.78 MHz, and an electromagnetic interference, EMI, filtered bridge rectifier to convert the transdermally received RF power to DC. The wire coil may be molded into the Reservoir Case  401 . The Receive Resonator  403  may also receive transdermal communication from the External Controller  103  and send it to a Power Receiving Unit, PRU,  405  for processing. 
         [0048]    Implant electronics may be housed on a military-grade coated Flex Circuit Board  404  for protection and waterproofing. Flexible circuit board packaging may facilitate Reservoir Case  401  implantation by the surgeon. The circuit board may be molded into the Reservoir Case  401  wall along with the Receive Resonator Filter  403  or wrapped around the motor and pump and coated with waterproof plastic. This package may be suspended in the center of the Reservoir Case  401 . The board and its components may be MRI-conditional. 
         [0049]    The PRU,  405  may convert the widely varying DC output of the Receiver Resonator  403  to a constant voltage DC output. Receiver Resonator&#39;s wide voltage variance may be caused by differences in separation over time and patients between the Transmitting Resonator  309  and the Receiving Resonator  403 . 
         [0050]    The PRU  405  may provide power to a Microprocessor  406  and Triple Power Amplifiers  408 . It may also process bidirectional communications from Receive Resonator  403 . Signals sent from the External Controller  103  are fed to the Microprocessor  406  and data from the Microprocessor  406  are sent to the Receiver Resonator  403  for transmission to the External Controller  103 . 
         [0051]    Upon reception of a start signal, the Microprocessor  406 , such as a MSP430 series or ADuCM320, may generate and digital-to-analog convert three sinusoids set 120° apart. The sinusoidal frequency and the number of sinusoidal cycles to be generated may be set from the Physician&#39;s Software Application  101 . The physician may select the number of cycles generated to set the number of rotary pump revolutions, and, for a fixed displacement pump, the amount of fluid transferred to inflate and deflate the cylinders and cuffs. Pump operation may also be set by using pressure data from the Pump Pressure and revolutions per minute, RPM, sensor  412 ; however, counting pump revolutions may be safer as it limits the amount of fluid transferred under leakage conditions. 
         [0052]    Switching between inflation and deflation may be achieved by switching two phases of the three 3-phase signals, which reverses motor direction. The Microprocessor  406  may also receive, process, and format implant performance and safety data for transmission to the External Controller  103 . In some implementations, additional analog-to-digital and digital-to-analog integrated circuit chips may be included. 
         [0053]    The 3-phase signals generated by the Microprocessor  406  may then feed Triple Power Amplifiers  408 , which then generate the power to operate the 3-Phase Squirrel Cage Motors  409  or synchronous motors. Current and voltage at the Triple Power Amplifiers  408  may be monitored by the Microprocessor  406  to detect faults for safe operation. 
         [0054]    This apparatus may include a nonferrous, 3-phase, 4-pole squirrel cage motors  409  or a synchronous motor to drive a Reduction Gear  410  and a Reversible Pump  411 . A 3-phase squirrel cage or synchronous motor has the advantages of small size, self-starting, high frequency operation. Squirrel cage motors do not use brushes or slip rings, wear items which may reduce motor life. 
         [0055]    The starting basis for the apparatus, and therefore motor and pump selection, is size, the amount of fluid that must be pumped to inflate the Inflatable Medical Implant  106  and patient convenience including the time it takes to inflate and deflate the implant. These parameters are physician set at the beginning of the apparatus design process. Water pumping equations are then used to determine how much power is required at the pump output, and, accounting for pump efficiency, how much power is required at the pump input. MRI-unsafe ferrous DC motor and pump combinations are widely available to meet these parameters. 
         [0056]    But these motors use ferrous materials to greatly increase torque by concentrating magnetic flux linkages between the motor&#39;s stator and rotor. For a constant speed motor, removing ferrous materials for MRI safety reduces flux linkages thereby greatly reducing torque, and, therefore power output, which is proportional to shaft speed multiplied by torque. The apparatus shown in  FIGS. 4A and 4B  makes up for lost nonferrous motor torque by increasing motor speed as much as possible, thereby buying back some of the lost motor power. But pumps are not efficient at high speeds, so a Reduction Gear  410  is introduced to match the high speed, low torque motor to the lower speed, higher torque pump, thereby optimizing the combination&#39;s efficiency and size. 
         [0057]      FIGS. 5A and 5B  illustrate an example of a 20 mm diameter by 25 mm long, 3-phase 4-pole squirrel cage motor, supplied with 14.9 Vrms 2300 Hz power, and operating at 50,000-rpm.  FIG. 5A  shows the motor&#39;s 4-pole stator windings and interconnections  501  and the squirrel cage bars with short circuiting endplates  502 . In  FIG. 5B , the stator  503  and the rotor  504  have be encapsulated in molded plastic to reduce windage losses and to stabilize the Rotor  504  under centrifugal force. The nonferrous motor may drive a nonferrous 25:1 reduction gear and pump to adequately inflate the penile cylinders in good time. Cuffs require much less fluid transfer; therefore a much smaller motor without reduction gear may be used. 
         [0058]    Therefore, as shown in  FIG. 4A , the apparatus may include a nonferrous Squirrel Cage Motor  409  or a 3-phase synchronous motor, planetary Reduction Gear  410  and positive displacement Reversible Pump  411  to pump Isotonic Fluid  402  from the reservoir to the Inflatable Medical Implant  106 . 
         [0059]    Pump Pressure and RPM sensors  412  may be provided along with a reservoir Pressure Sensor  414 . Pressure and RPM data may be sent to the Microprocessor  406 . The pressure and RPM data may be used for automatic cutoff should the pump run over or under speed limits, leakage, over inflation or a fluid blockage occur and to help the physician set the amount of fluid to be transferred that is best for the patient. 
         [0060]    A Thermistor  415  may be included on the Flexible Circuits Board  404  to send temperature data to the Microprocessor  406  for high temperature cutoff should the Isotonic Fluid  402  overheat. Additionally, integrated circuit chips used in the Power Receiving Unit  405 , Microprocessor  406  and Triple Power Amplifiers  408  may have internal temperatures sensors that turn off the chip in over temperature situations. 
         [0061]    Should the apparatus fail with the Inflatable Medical Implant  106  inflated, a Pressure Relief Tube  413  may be provided to allow physicians to manually deflate the Inflatable Medical Implant  106  by inserting a small bore hypodermic needle into the tube and drawing out the inflating fluid. One end of the tube may be located at the output of the Reversible Pump  412  and the other end just below the skin. 
         [0062]    The Reversible Pump  413  may be connected to the Inflatable Medical Implant  106  through Tubing  105  which the surgeon threads from the Reservoir Case  401  to the Inflatable Medical Implant  106 . At this time, the surgeon may fill the Implant Case  401  with Isotonic Fluid  402  through the Fill Port  416 . Filling may be accomplished by inserting a hypodermic needle through the self-sealing Fill Port  416 . 
         [0063]      FIG. 4B  shows the MRI-conditional apparatus operating three implants. The Figure shows a dual Penile Cylinder Implant  417 , a Urethra Cuff Implant  418  and an Anal Cuff Implant  419  example. 
         [0064]      FIG. 6  shows a diagram of the MRI-unsafe Pump in Reservoir Implant implementation. The implementation of  FIG. 6  includes many of the same components already described in  FIGS. 4A and 4B . However, in  FIG. 6 , the nonferrous pump and motor  409 ,  410 ,  411  from  FIGS. 4A and 4B  may be replaced by a reversible DC motor  609  and pump  611  combination. Reduction Gear  410  may not be needed. The coupling between the motor  609  and pump  611  may be magnetic allowing the pump to be in contact with the Isotonic Fluid  402  without the need for seals in the motor, thereby increasing efficiency and reliability. Also, the Triple Power Amplifier  408  may be replaced by connecting to the PRU&#39;s  405  DC output voltage through a Microprocessor  406  controlled solid state DC Forward-Reverse-Off Switch  608  to turn the motor on and off and to reverse its direction.