WO2022178041A1

WO2022178041A1 - Apparatus for tumor therapy and monitoring

Info

Publication number: WO2022178041A1
Application number: PCT/US2022/016673
Authority: WO
Inventors: Sergei Kurenov
Original assignee: Health Research, Inc.
Priority date: 2021-02-16
Filing date: 2022-02-16
Publication date: 2022-08-25

Abstract

In some embodiments, an apparatus for implantable therapy includes a power supply and a first implantable component. The power supply includes a transmitter configured to provide a first signal at a first frequency. The power supply also includes a receiver configured to receive a second signal at a harmonic of the first frequency. The first implantable component includes an LC circuit configured to resonate at the first frequency. One or more light-emitting diodes (LEDs) of the first implantable component are configured to be powered by the first signal received at the LC circuit. In this way, powering the one or more LEDs forms a harmonic of the first signal (e.g., a third harmonic of the first signal). In some embodiments, the apparatus include a second implantable component with a sensor, which may be a light sensor.

Description

APPARATUS FOR TUMOR THERAPY AND MONITORING

Cross-Reference to Related Applications

[0001] This application claims priority to U.S. Provisional Application No. 63/150,074, filed on February 16, 2021, now pending, the disclosure of which is incorporated herein by reference.

Field of the Disclosure

[0002] The present disclosure relates to systems and methods for implantable therapy, and more particularly to a wirelessly-powered device and method for photodynamic therapy.

Background of the Disclosure

[0003] Light therapy can be used for treatment of conditions in multiple ways. For example, interstitial light therapies (ILT) involve the delivery of a therapeutic light through one or more optical fibers placed within a target tumor. ILT can be combined with prior administration of light sensitive medicine ( e.g ., photosensitizer) that absorbs the therapeutic light and interacts with surrounding tissue constituents (e.g., oxygen) to generate reactive species that can destroy the target tissue. This form of therapy is known as interstitial photodynamic therapy (I-PDT). I-PDT uses light (such as light provided by a laser) delivered to a target tissue by an optical fiber to activate a photosensitizer. It is associated with mild side effects and can be combined with standard chemotherapy and surgery, and followed with radiation therapy. However, because the optical fiber(s) must traverse through the skin of the individual, the therapy can be uncomfortable and may be somewhat limited in duration.

Brief Summary of the Disclosure

[0004] In a first aspect, the present disclosure may be embodied as an apparatus for implantable therapy. The apparatus includes a power supply and a first implantable component. The power supply includes a transmitter configured to provide a first signal at a first frequency. The transmitter may be an LC circuit configured to resonate at the first frequency. The first frequency may have a value selected from the range of 100 kHz to 500 kHz, inclusive. The power supply also includes a receiver configured to receive a second signal at a harmonic of the first frequency. [0005] The first implantable component includes an LC circuit configured to resonate at the first frequency. One or more light-emitting diodes (LEDs) of the first implantable component are configured to be powered by the first signal received at the LC circuit. In this way, powering the one or more LEDs forms a harmonic of the first signal ( e.g ., a third harmonic of the first signal). The one or more LEDs of the first implantable component may include two LEDs, and wherein each LED is connected to the LC circuit with a polarity which is the opposite of the other LED.

[0006] In some embodiments of the apparatus, the first implantable component further includes a sensor configured to provide a sensor signal based on a measured parameter. The first implantable component may also have a component transmitter to transmit the sensor signal. The component transmitter may be configured to modulate the sensor signal on the second signal.

The first implantable component may also have a microprocessor programmed to receive the sensor signal and provide a processed signal to the component transmitter.

[0007] In some embodiments of the apparatus, the first implantable component further includes a heating element. In some embodiments, the heating element may be in communication with a microprocessor and the microprocessor is further programmed to control the heating element.

[0008] In another aspect, the present disclosure may be embodied as an apparatus for photodynamic therapy. The apparatus includes a power supply, a first implantable component, and a second implantable component. The power supply includes a transmitter configured to provide a first signal at a first frequency, and a receiver configured to receive a second signal.

[0009] The first implantable component has an LC circuit configured to resonate at the first frequency. The first implantable component also includes one or more light sources configured to be powered by the signal received at the LC circuit. The one or more light sources may be light-emitting diodes (LEDs). Powering the one or more light sources may form a harmonic of the first signal (e.g., a third harmonic). The apparatus may include a plurality (i.e., more than one) of the first implantable components.

[0010] The second implantable component includes a sensor configured to provide a sensor signal based on a measured parameter. In some embodiments, the sensor of the second implantable component is a light sensor configured to detect and/or measure light emitted from the first implantable component. The second implantable component may further include an LC circuit configured to resonate at the first frequency. The second implantable component may further include a component transmitter configured to transmit the sensor signal. The apparatus may include a plurality ( i.e more than one) of the second implantable components. In some embodiments, the sensor is a temperature sensor. In some embodiments, the second implantable component includes more than one sensor (which may be the same type of sensor, different types of sensors, or combinations of same and different sensors).

[0011] In another aspect, the present disclosure may be embodied as a method for implantable photodynamic therapy. The method includes receiving, at a first implantable component, a power signal at a first frequency. A light is generated using a light source of the first implantable component such that the light source clamps the power signal thereby generating a third harmonic. The method includes receiving, at an external power supply, the generated third harmonic signal so as to confirm activation of the light source of the implantable component. In some embodiments, the light source is configured to clamp a positive component and a negative component of the power signal.

Description of the Drawings

[0012] For a fuller understanding of the nature and objects of the disclosure, reference should be made to the following detailed description taken in conjunction with the accompanying drawings, in which:

Figure 1 A is a diagram of an apparatus according to an embodiment of the present disclosure;

Figure IB is a diagram of a first implantable component of the apparatus of Figure 1 A;

Figure 1C is a diagram of a second implantable component of the apparatus of Figure IB;

Figure 2 is a diagram of an apparatus according to another embodiment of the present disclosure;

Figure 3 is a diagram of an external component according to an embodiment of the present disclosure;

Figure 4 is a schematic of an implantable component according to an embodiment of the present disclosure;

Figure 5 is experimental data showing received signals when LEDs are not activated (the clamp of sinusoidal signal does not appear); Figure 6 shows the frequency spectrum of the signal of Figure 5;

Figure 7 is experimental data showing received signals when LEDs are activated (the clamp of sinusoidal signal is apparent);

Figure 8 shows the frequency spectrum of the signal of Figure 7 (showing a peak at the third harmonic -342 kHz of the first frequency -114 kHz);

Figure 9 shows a graph of implanting receiver output voltage vs. deviation of implantable component LC circuit resonance from external power supply transmitting frequency (illustrating that with loads such as LEDs, an exact match between the resonance frequencies of external and internal components is not required);

Figure 10 shows another embodiment of an implantable component according to the present disclosure;

Figure 11 shows another embodiment of an implantable component according to the present disclosure;

Figure 12A shows a circuit model of power transmitting between an external component and an implantable component;

Figure 12B shows a graph of the signal in the circuit model of Figure 12A;

Figure 13 shows a photograph of an experimental apparatus where a plurality of first implantable components (some having red LEDs and some having white LEDs) were placed on a 75 mm tall phantom, a wireless transmitter ( e.g antenna) surrounded a base of the phantom, and a light detection probe was placed near the LEDs to provide spectral analysis and light intensity measurements;

Figures 14A and 14B are charts showing measurements of the peak intensity of the red light and white light, respectively, using the experimental apparatus of Figure 13;

Figure 15A shows image acquisition (CT scan), processing, and segmentation of a nodule of a human lung;

Figure 15B shows a 3-dimensional (3D) mesh model created based on the nodule and steps of Figure 15A (Tumor Model: human lung nodule, Tumor Treatment Volume: 416 mm³, Tumor Treatment Size (along longest axis): 9.6 mm (x-axis) x 9.2 mm (y-axis) x 8.9 mm (z-axis));

Figure 16A shows the setup of an exemplary finite element method (FEM) simulation of photodynamic therapy (PDT) using a single conventional laser fiber and showing the laser fiber in orthographic projection with coordinates, orientation, diffuser length, and power (where the laser fiber parameters were: diameter (m): 1.2e ³, length (m) 20.0e ³, input light intensity (power): 400 mW/cm (FDA approved for interstitial PDT with PHOTOFRIN®, light wavelength = 630 nm);

Figure 16B shows two simulation plots of the FEM setup of Figure 16A;

Figure 17A shows the setup of an exemplary FEM simulation of PDT using eight LEDs (where the LED parameters used were: diameter (m): l.Oe ³, length (m): 1.8 e ³, maximum input light intensity (power): 2 mW/cm, light wavelength = 630 nm);

Figure 17B shows a simulation plot of the FEM setup of Figure 17A;

Figure 18A shows the setup of an exemplary FEM simulation of PDT using eight LEDs (where the LED parameters used were: diameter (m): l.Oe ³, length (m): 1.8 e ³, maximum input light intensity (power): 2 mW/cm, light wavelength = 630 nm); and

Figure 18B shows a simulation plot of the FEM setup of Figure 18 A.

Detailed Description of the Disclosure

[0013] In a first aspect, an apparatus according to an embodiment of the present disclosure includes a power supply and an implantable component. The implantable component may be implanted adjacent to and/or at least partially within a tissue of an individual. For example, the implantable component may be implanted adjacent to and/or at least partially within a tumor for use in photodynamic therapy (PDT). The power supply includes an LC circuit with a resonant frequency at a first frequency.

[0014] The implantable component includes an LC circuit configured to resonate at the first frequency. In this way, the implantable component may couple with the power supply and receive a power signal from the power supply. The implantable component further comprises a light source configured to be powered by the LC circuit. The light source may be, for example, one or more light-emitting diodes (LEDs). In some embodiments, the light source is made up of two LEDs connected with opposite polarity such that each LED is powered by a respective positive or negative portion of a power signal from the LC circuit. The resonant frequency may be, for example, in a range from 100 kHz to 500 kHz, though devices may be configured with a higher or lower resonant frequency. In a particular exemplary embodiment, wherein a prototype apparatus was constructed, the resonant frequency was 277 kHz. In the exemplary embodiment, the implantable component of the prototype was cylindrical in shape and measured approximately 3x3 mm. Further refinement of the implementing hardware may enable implantable components that are smaller than this prototype. [0015] Where a sinusoidal signal is sent by the power supply LC circuit resonating at the first frequency and received by the LC circuit of the implantable component, the LEDs will clamp the sinusoidal signal due to the voltage drop across each LED. For example, where two LEDs are provided, the first LED will clamp a positive portion of the sinusoidal signal and the second LED will clamp a negative portion of the sinusoidal signal. Clamping the power signal in this way results in a waveform with a large third harmonic component of the first signal. This waveform within the implantable component is transmitted and can be received outside the implantable component.

[0016] The power supply includes a receiver sensitive to the third harmonic of the power signal. For example, in the exemplary embodiment having a first resonance frequency of 277 kHz, the receiver may be configured to be sensitive to a signal at 831 kHz.

[0017] In the exemplary embodiment, power was able to be transmitted from the

(external) power supply to the implantable component at the common resonance frequency (first frequency) at a distance of up to 15 inches (~38 cm). The received third harmonic signal may be used to inform adjustments the position of external power supply near the body and also to provide confirmation that the LED(s) are actually activated.

[0018] With reference to Figures 1A-1C, the present disclosure may be embodied as an apparatus 10 for implantable therapy. The apparatus includes a power supply 20 having a transmitter 22 configured to provide a first signal at a first frequency. The transmitter 22 may be, for example, a so-called LC circuit, having an inductor coil and a capacitor (further described below and with reference to Figure 2). The inductor coil and capacitor may have values selected such that the LC circuit resonates at the first frequency.

[0019] Apparatus 10 further includes an implantable component 30 having an LC circuit 32 configured to resonate at the first frequency — for example, each of an inductor and a capacitor of the LC circuit 32 having values selected such that the LC circuit of the implantable component 30 resonates at a frequency which is the same or substantially the same as the first frequency. By substantially the same, in various embodiments, it is intended that the resonance frequency of the LC circuit 32 is ±5%, ±10%, ±20%, or ±30% of the first frequency, or other values therebetween. [0020] The implantable component 30 further includes one or more LEDs 34. The one or more LEDs 34 are configured to be powered by the first signal received by the LC circuit 32 of the implantable component 30. By powering the one or more LEDs, a harmonic (or harmonics) will be formed from the received first signal thereby generating a second signal at a harmonic of the first signal). For example, the second signal may be a third harmonic of the first signal.

[0021] The power supply 20 includes a receiver 24 configured to receive the second signal. In this way, the receiver 24 of the power supply 20 may be used to confirm that the one or more LEDs 34 of the implantable component 30 are operating. The power supply may include, or may be connected to, an indicator circuit so as to indicate when a third harmonic signal has been detected. The indicator circuit may be, or may include, a processor, a controller, a computer, etc.

[0022] In another embodiment, an apparatus 10 for photodynamic therapy is provided.

The apparatus has a power supply 20 having a transmitter 22 configured to provide a first signal at a first frequency. The power supply 20 also includes a transmitter 24 configured to receive a second signal.

[0023] A first implantable component 30 is used to provide therapeutic light for use in

PDT. The first implantable component 30 includes an LC circuit configured to resonate at or substantially at the first frequency. The one or more light sources may be LEDs. One or more light sources 34 are configured to be powered by the first signal received at the LC circuit 32. In some embodiments, the apparatus includes a plurality ( e.g ., more than one) first implantable components 30 (see, e.g., Figure 1 A).

[0024] A second implantable component 40 has a sensor 44 configured to provide a sensor signal based on a measured parameter. For example, the sensor may be a light sensor configured to detect and/or measure light. In this way, the second implantable component 40 may be used for dosimetry to determine the light dose provided during PDT. The second implantable component 40 may include an LC circuit 42 configured to resonate at the first frequency. In some embodiments, the second implantable component is powered by the received first signal. In some embodiments, the apparatus includes a plurality (e.g, more than one) second implantable components 40 (see, e.g, Figure 1A). [0025] Figure 2 shows a general diagram of an exemplary embodiment of an apparatus according to another embodiment of the present disclosure, Figure 3 is a diagram of the external power supply 100 shown in Figure 2, and Figure 4 is a diagram of a first implantable component 200 shown in Figure 2. External power supply 100 includes an LC circuit having an inductor coil 106 (the ‘L’ component) and a capacitor 107 (the ‘C’ component) where the inductor coil 106 and capacitor 107 have values selected such that the LC circuit resonates at the first frequency — for example, a pre-determined first frequency. The LC circuit may receive power from a power source 101 by way of a power amplifier 104. A wave generator 102 may be configured to provide a signal at a generated frequency to a frequency divider 103 which is configured to divide the generated frequency by 3. In this way, the power amplifier 104 may modulate the power from the power source 101 at the frequency divided signal from the frequency divider 103 — resulting in a power signal at the first frequency. The wave generator 102 may also provide a signal to a receiver 108 configured to be sensitive at the third harmonic of the first frequency (i.e., the frequency of the signal from the wave generator 102). The receiver 108 may have an antenna 109 tuned to the third harmonic of the first frequency. An indicator circuit 110, such as, for example, a computer, may be in communication with the receiver 108 to indicate when a third harmonic signal is received.

[0026] The first implantable component 200 of the apparatus is configured to be implanted near or (partially or fully) inside the tumor. An exemplary embodiment of the implantable component 200 includes an LC circuit having an inductor coil 201 and a capacitor 202, each having values selected such that the LC circuit of the first implantable component 200 resonates at a frequency which is substantially the same as the first frequency. The implantable component has two LEDs 203, 204 configured to provide illumination light at a wavelength corresponding with a particular drug for treatment of a tumor. In some embodiments, the first implantable component may have more than two LEDs. For example, the first implantable component may have four LEDs wherein two pairs of LEDs are connected with opposite polarities from each other.

[0027] A power signal 111 is provided by the external power supply 100 at a first frequency selected in the range of, for example, 100 kHz to 500 kHz. A power signal received at an exemplary first implantable component without activated LEDS is shown in Figures 5 (time domain) and 6 (frequency domain). The power signal 111 is received by the first implantable component 200 thereby powering on the LEDs. When powered on, the activated LEDs 203, 204 clamp the sinusoidal signal across the LC circuit in the first implantable component 200 resulting in transmission of a signal 205 at a third harmonic of the first frequency, for example, in the range of 300 kHz to 1.5 MHz. A clamped (third harmonic) signal from the exemplary first implantable component is shown in Figures 7 (time domain) and 8 (frequency domain) The third harmonic signal 205 is received by antenna 109 of the external power supply 100. In this way, the received third harmonic signal 205 provides assurance that the LEDs 203,204 are active within the first implantable component 200 and thereby providing confirmation that the tumor is receiving treatment light for activation of the photodynamic therapy drug. Further, the relative strength of the received third harmonic signal 205 may be measured to allow an operator to reposition the external power supply 100 so as to improve the power received by the first implantable component 200.

[0028] Figure 9 shows a plot of the output voltage from the receiver (LC circuit) of an exemplary implantable component versus a percentage deviation between the implantable component LC circuit resonance from the power supply transmitting frequency. The graph shows that with LED loads in the implantable component, an exact match between the resonance frequencies of the power supply (i.e., first signal) and the implantable component (on which the second signal is generated) is not necessary, and the apparatus will function even with a difference in resonance frequencies.

[0029] Figure 10 shows another embodiment of an implantable component 300 further comprising a sensor. The sensor 301 may be configured to sense a parameter of the implantable component 300 itself and/or a parameter of the environment in which the implantable component is placed. For example, the sensor may sense interstitial fluid pressure, temperature, etc. which are indicative of tumor therapy progress. A signal from the sensor 301 may be modulated by modulator 303 across the LC circuit of the internal component 300 so as to be transmitted 306 to the external power supply. The sensor signal may be an input into a microprocessor 304 which may be programmed to provide a signal to the modulator 303. For example, the microprocessor 304 may be programmed to provide periodical sensor data transmission, for instance once per hour.

[0030] Figure 11 shows another embodiment of an implantable component 400 further comprising a heating element 401. Such a heating element 401 may further accelerate the tumor terminating process. In some embodiments, the heating element 401 is controlled by a microprocessor 404. In some embodiments, the heating element may be configured such that when the heating element is activated, the voltage across the LC circuit will drop below the LED activated limit (typically below 4 Volts peak-to-peak), which will deactivate the LEDs such that more of the power received by the LC circuit of the implantable component can be used by the heating element 401 (for example, for a duration defined by microprocessor 404.

[0031] Figure 12A shows a model to simulate power transmission between an external power supply and implantable component according to an embodiment of the present disclosure. The equation which describes the power transmission is:

where

and

and where V_out and V_gen are the output voltages on the receiver Rx and the generator Tx, respectively; Z_x is the transmitter impedance; Z₂ is the receiver impedance; j is the imaginary unit; w is the frequency;

the self-resistance of the transmitting coil; R₂ is the self-resi stance of the microchip; R₃ is the self-resistance of the receiving coil; R₄ is the parasitic resistance coupled by the mutual inductance L₂ ; and L₁ and L₂ are the self-inductances of the transmitter coil and receiver coil, respectively.

[0032] Figure 12B shows a plot of the voltage amplitude cross the LC circuit of the implantable component versus the power transmitting frequency without LEDs but with a load taking approximately 10 mA RMS of current presented by passive resistor R₃ shown in the schematic of the model in Figure 12A. Test Embodiment and Simulations

[0033] An experimental embodiment was used to simulate treatment using the wirelessly-powered LED versus a conventional laser fiber therapy based on a reconstructed 3D model of a lung nodule. An objective of the test was to determine the feasibility of wirelessly- powered photodynamic therapy (PDT) for tumors in locations inaccessible using conventional laser-based PDT. Additionally, the efficiency of wirelessly-powered LEDs was compared with conventional PDT.

[0034] A plastic phantom with a height of 75 mm was placed within a wireless transmitter as shown in Figure 13. Wirelessly-powered LEDs were placed on the phantom as shown in the figure. A light detector probe was placed near the LEDs to provide spectral analysis and light intensity measurements (see Figures 14A and 14B).

[0035] In other testing, finite-element method (FEM) simulations were conducted to determine performance of a laser-based PDT embodiment compared to an LED-based PDT embodiment. Table I below shows the optical properties used for the FEM simulations.

Figure 15A shows image acquisition, processing, and segmentation of a human lung to create a tumor model for FEM simulation. Figure 15B shows the resulting tumor model used (the optical properties are shown in Table I below).

Table I: Tumor optical properties

[0036] Figures 16-18 show the results of the FEM simulations — where Figures 16A and 16B show simulation of a single standard PDT laser fiber, Figures 17A and 17B show simulation of a single LED for wireless PDT, and Figures 18A and 18B show simulation of eight LEDs for wireless PDT. Results, including simulated treatment time, minimum irradiance to 100% of the tumor volume, and minimum fluence to 100% of the tumor volume, are shown in Table II below. Table II: Results of FEM simulation of treatment.

[0037] In another aspect, the present disclosure may be embodied as a method for implantable photodynamic therapy. The method includes receiving, at a first implantable component, a power signal at a first frequency. A light is generated using a light source of the first implantable component such that the light source clamps the power signal thereby generating a third harmonic. The method includes receiving, at an external power supply, the generated third harmonic signal so as to confirm activation of the light source of the implantable component. In some embodiments, the light source is configured to clamp a positive component and a negative component of the power signal.

[0038] Further examples:

[0039] Example 1. An apparatus for implantable therapy, having a power supply, the power supply having a transmitter configured to provide a first signal at a first frequency and a receiver configured to receive a second signal at a harmonic of the first frequency; a first implantable component, the first implantable component having an LC circuit configured to resonate at the first frequency and one or more LEDs configured to be powered by the first signal received at the LC circuit such that powering the one or more LEDs forms a harmonic of the first signal.

[0040] Example 2. The apparatus of example 1, wherein the transmitter is an LC circuit configured to resonate at the first frequency. [0041] Example 3. The apparatus of any one of examples 1 or 2, wherein the receiver is configured to receive the second signal at a third harmonic of the first frequency.

[0042] Example 4. The apparatus of any one of examples 1-3, wherein the first implantable component includes two LEDs, and wherein each LED is connected to the LC circuit with a polarity which is the opposite of the other LED. [0043] Example 5. The apparatus of any one of examples 1-4, wherein the first frequency has a value selected from the range of 100 kHz to 500 kHz, inclusive.

[0044] Example 6. The apparatus of any one of examples 1-5, wherein the first implantable component further includes a sensor configured to provide a sensor signal based on a measured parameter, and a component transmitter configured to transmit the sensor signal. [0045] Example 7. The apparatus of example 6, wherein the component transmitter is configured to modulate the sensor signal on the second signal.

[0046] Example 8. The apparatus of example 6, wherein the first implantable component further includes a microprocessor programmed to receive the sensor signal and provide a processed signal to the component transmitter. [0047] Example 10. The apparatus of example 8, wherein the first implantable component further includes a heating element in communication with the microprocessor and the microprocessor is further programmed to control the heating element.

[0048] Example 11. The apparatus of any one of examples 1-10, wherein the first implantable component further includes a heating element. [0049] Example 12. An apparatus for photodynamic therapy, having: a power supply, the power supply having a transmitter configured to provide a first signal at a first frequency and a receiver configured to receive a second signal; a first implantable component, the first implantable component having an LC circuit configured to resonate at the first frequency and one or more light sources configured to be powered by the signal received at the LC circuit; and a second implantable component, the second implantable component having a sensor configured to provide a sensor signal based on a measured parameter and a component transmitter configured to transmit the sensor signal.

[0050] Example 13. The apparatus of example 12, wherein the second implantable component further includes an LC circuit configured to resonate at the first frequency.

[0051] Example 14. The apparatus of any one of examples 12-13, wherein the sensor of the second implantable component is a light sensor configured to detect and/or measure light emitted from the first implantable component.

[0052] Example 15. The apparatus of any one of examples 12-14, wherein the one or more light sources are light-emitting diodes (LEDs).

[0053] Example 16. The apparatus of any one of examples 12-15, wherein powering the one or more light sources forms a harmonic of the first signal. [0054] Example 17. The apparatus of any one of examples 12-16, further having a plurality of first implantable components.

[0055] Example 18. The apparatus of any one of examples 12-17, further having a plurality of second implantable components.

[0056] Example 19. The apparatus of any one of examples 12-18, wherein the sensor is a temperature sensor.

[0057] Example 20. The apparatus of any one of examples 12-19, wherein the second implantable component comprises a second sensor.

[0058] Example 21. A method for implantable photodynamic therapy, the method including: receiving, at a first implantable component, a power signal at a first frequency; generating light at a light source of the first implantable component such that the light source clamps the power signal so as to generate a third harmonic; receiving, at an external power supply, a third harmonic signal so as to confirm activation of the light source of the implantable component. [0059] Example 22. The method of example 21, wherein the light source is configured to clamp a positive component and a negative component of the power signal.

[0060] Although the present disclosure has been described with respect to one or more particular embodiments, it will be understood that other embodiments of the present disclosure may be made without departing from the spirit and scope of the present disclosure.

Claims

What is claimed is:

1. An apparatus for implantable therapy, comprising: a power supply, comprising: a transmitter configured to provide a first signal at a first frequency; and a receiver configured to receive a second signal at a harmonic of the first frequency; and a first implantable component, comprising: an LC circuit configured to resonate at the first frequency; and one or more LEDs configured to be powered by the first signal received at the LC circuit such that powering the one or more LEDs forms a harmonic of the first signal.

2. The apparatus of claim 1, wherein the transmitter is an LC circuit configured to resonate at the first frequency.

3. The apparatus of claim 1, wherein the receiver is configured to receive the second signal at a third harmonic of the first frequency.

4. The apparatus of claim 1, wherein the first implantable component comprises two LEDs, and wherein each LED is connected to the LC circuit with a polarity which is the opposite of the other LED.

5. The apparatus of claim 1, wherein the first frequency has a value selected from the range of 100 kHz to 500 kHz, inclusive.

6. The apparatus of claim 1, wherein the first implantable component further comprises a sensor configured to provide a sensor signal based on a measured parameter, and a component transmitter configured to transmit the sensor signal.

7. The apparatus of claim 6, wherein the component transmitter is configured to modulate the sensor signal on the second signal.

8. The apparatus of claim 6, wherein the first implantable component further comprises a microprocessor programmed to receive the sensor signal and provide a processed signal to the component transmitter.

10. The apparatus of claim 8, wherein the first implantable component further comprises a heating element in communication with the microprocessor and the microprocessor is further programmed to control the heating element.

11. The apparatus of claim 1, wherein the first implantable component further comprises a heating element.

12. An apparatus for photodynamic therapy, comprising: a power supply, comprising: a transmitter configured to provide a first signal at a first frequency; and a receiver configured to receive a second signal; a first implantable component, comprising: an LC circuit configured to resonate at the first frequency; and one or more light sources configured to be powered by the signal received at the LC circuit; and a second implantable component, comprising: a sensor configured to provide a sensor signal based on a measured parameter; and a component transmitter configured to transmit the sensor signal.

13. The apparatus of claim 12, wherein the second implantable component further comprises an LC circuit configured to resonate at the first frequency.

14. The apparatus of claim 12, wherein the sensor of the second implantable component is a light sensor configured to detect and/or measure light emitted from the first implantable component.

15. The apparatus of claim 12, wherein the one or more light sources are light-emitting diodes (LEDs).

16. The apparatus of claim 12, wherein powering the one or more light sources forms a harmonic of the first signal.

17. The apparatus of claim 12, further comprising a plurality of first implantable components.

18. The apparatus of claim 12, further comprising a plurality of second implantable components.

19. The apparatus of claim 12, wherein the sensor is a temperature sensor.

20. The apparatus of claim 12, wherein the second implantable component comprises a second sensor.

21. A method for implantable photodynamic therapy, comprising: receiving, at a first implantable component, a power signal at a first frequency; generating light at a light source of the first implantable component such that the light source clamps the power signal so as to generate a third harmonic; receiving, at an external power supply, a third harmonic signal so as to confirm activation of the light source of the implantable component.

22. The method of claim 21, wherein the light source is configured to clamp a positive component and a negative component of the power signal.