Biodegradable wireless in vivo dosimetry system for monitoring radiotherapy

Abstract

A biodegradable wireless dosimetry system (100) for in vivo verification of radiotherapy, wherein the system (100) comprises: a biodegradable wireless in vivo dosimeter unit (1); and an external reading unit (2) wirelessly coupled to the biodegradable wireless in vivo dosimeter unit (1); the biodegradable wireless in vivo dosimeter unit (1) comprises: a power receiving and rectifying unit (PWR) comprising a near-field receiver (3) and a rectifier (4) implemented with at least one biodegradable conductor or biodegradable compound (5), wherein the power receiving and rectifying unit (PWR) is configured to receive electromagnetic energy from the external reading unit (2) and generate a DC power supply; an energy buffer block (ENB) comprising a biodegradable electrochemical energy buffer (6) configured as a Zn-ion hybrid micro-supercapacitor (7), electrically coupled to the rectifier (4) and designed to stabilize the DC power supply during intermittent wireless coupling; a radiation sensor block (RSB) with a radiation transduction module (8) configured to generate a dose-proportional signal in response to absorbed ionizing radiation; an optional physiological sensor block (PSB) with at least one additional physiological sensor (20); a telemetry and control block (TCB) (40) configured to process the dose-proportional signal and all physiological sensor signals and to provide wireless telemetry to the external reading unit (2); and a resorbable encapsulation block (9) enclosing the near-field receiver (3), rectifier (4), energy buffer (6, 7), radiation transduction module (8), physiological auxiliary sensor (20) and telemetry and control block (40), wherein the resorbable encapsulation block (9) is configured to maintain the integrity of the device during a predefined clinical monitoring period and is subsequently biodegraded under physiological conditions; wherein the external reading unit (2) comprises a corresponding block diagram architecture: a coupling and power transfer block (CPB) with a transmit / receive coil (35) configured to couple with the near-field receiver (3) and to power the biodegradable wireless in vivo dosimeter unit (1); a signal processing block (SPB) (36) configured to demodulate and process telemetry data received from the telemetry and control block (40); a memory block (38) configured to store calibration data and measured dose information; and a user interface block (37) configured to display at least one parameter indicating the absorbed dose for verification of a radiotherapy plan, wherein the blocks (PWR, ENB, RSB, PSB, TCB, CPB, SPB, memory block (38) and user interface block (37)) are arranged such that a block diagram of the system (100) is defined by these functional units and their interconnections.

Description

INVENTION AREA

[0001] The present invention relates to the field of radiation dosimetry and medical devices used to monitor the radiation dose delivered during radiotherapy treatments. In particular, the invention relates to a biodegradable wireless in vivo dosimeter system (100) configured for use in body cavities during radiotherapy, wherein the system comprises a biodegradable wireless in vivo dosimeter unit and an external reading unit (2) which together enable real-time monitoring of the absorbed radiation dose using near-field wireless energy transmission and telemetry.

[0002] In particular, the present invention relates to a biodegradable wireless in vivo dosimeter system for monitoring radiotherapy. BACKGROUND OF THE INVENTION

[0003] The subject matter discussed in the "Background" section should not be considered prior art solely because it is mentioned in that section. Likewise, a problem mentioned in the "Background" section or related to the subject matter of the "Background" section should not be considered prior art. The subject matter in the "Background" section merely presents various approaches, which could themselves also be inventions.

[0004] External beam radiation therapy and brachytherapy are frequently used to treat cancer and other diseases. In such treatments, it is essential that the prescribed radiation dose is delivered precisely to the target volume, while keeping the dose to surrounding healthy tissue and vulnerable organs as low as possible.

[0005] Currently, pre-treatment dose verification is often performed using phantoms and external detectors. In vivo dosimetry, which measures the dose during treatment directly in or near the patient's body, is limited by the size, rigidity, lack of wireless capability, and non-biodegradability of existing sensors. Conventional in vivo detectors may require wiring, cause discomfort, or need to be removed after treatment, increasing clinical complexity and patient burden.

[0006] There is also a growing need for dosimeter devices that function reliably during radiation gating, gantry movements, and patient movement, and that can safely remain in the body to dissolve after treatment. Existing battery-powered implantable dosimeters are not biodegradable, raise concerns about long-term in-body retention, and can interfere with imaging or subsequent procedures.

[0007] Accordingly, there is a need for a compact, fully or predominantly biodegradable wireless dosimeter that can be temporarily placed in a body cavity, is wirelessly powered, is capable of transmitting dose information in real time, and is designed to be bioresorbed after a controlled functional lifetime. There is also a need for a reader unit that can reliably power such a dosimeter and process the measured signals for clinical decision-making.

[0008] The use of any examples or illustrative phrases (e.g., "as") relating to specific embodiments serves only to better illustrate the invention and does not constitute a limitation of the scope of the invention as claimed elsewhere. No phrase in the description should be interpreted as referring to an unclaimed element that is essential to carrying out the invention.

[0009] The information disclosed above in this "Background" section is provided solely for a better understanding of the background of the invention and may therefore contain information that is not part of the prior art already known to a person skilled in the art in this country. SUMMARY

[0010] Before describing the systems and methods presented here, it should be noted that this application is not limited to the specific systems and methods described, as there may be several possible embodiments not expressly presented in this disclosure. It should also be noted that the terminology used in the description serves only to describe the specific versions or embodiments and is not intended to limit the scope of this application.

[0011] According to one aspect, the invention provides a biodegradable wireless dosimeter system (100) comprising a biodegradable wireless in vivo dosimeter unit (1) and an external reading unit (2). The dosimeter unit (1) comprises, in a block diagram architecture, a power receiving and rectification block (PWR) with a near-field receiver (3) and a rectifier (4), an energy buffer block (ENB) with a biodegradable electrochemical energy buffer (6) in the form of a Zn-ion hybrid micro-supercapacitor (7), a radiation measurement block (RSB) with a radiation transduction module (8), an optional physiological measurement block (PSB) with at least one additional physiological sensor (20), a telemetry and control block (TCB) (40), and a resorbable encapsulation block (9) surrounding these elements.

[0012] The radiation transfer module (8) within the radiation measurement block (RSB) comprises a cintillation nanocomposite or a dosimetric polymer that converts absorbed ionizing radiation into a largely linear, dose-proportional electrical or optical signal over clinically relevant dose and dose rate ranges.

[0013] The optional physiological sensor block (PSB) includes at least one additional physiological sensor (20), for example, a temperature sensor and / or a pH sensor. These sensors monitor the local tissue environment and thus enable compensation for temperature- and pH-dependent fluctuations in the dosimetric response.

[0014] The telemetry and control block (TCB) (40) is powered by the energy buffer block (ENB) and is connected to the radiation sensor block (RSB) and the physiological sensor block (PSB). The TCB (40) performs signal conditioning and modulates the load of the near-field receiver (3) or uses a separate telemetry mechanism to transmit dose and physiological data to the external read unit (2).

[0015] The resorbable encapsulation block (9) encloses the internal blocks of the dosimeter unit (1). It consists of a multilayer polymer stack with materials such as poly(lactic acid-co-glycolic acid) (PLGA), poly(caprolactone) (PCL) and silk fibroin, which together provide mechanical protection and control the functional lifetime prior to bioresorption.

[0016] The external reading unit (2) comprises a coupling and power transfer block (CPB) with a transmit / receive coil (35) and a power driver (41), a signal processing block (SPB) (36), a memory block (38) for storing calibration and historical data, and a user interface block (37). The CPB provides power and receives telemetry data, while the SPB (36) demodulates the telemetry data, applies the calibration data stored in the memory block (38), and calculates corrected values ​​for the absorbed dose. The user interface block (37) displays numerical dose information and can provide a traffic light-style indicator and record time-stamped dose logs (39).

[0017] The entire biodegradable wireless in vivo dosimeter unit (1) is designed in a conformal geometry such as a capsule, soft insert, band or swallowable form and is configured for placement in the rectum, stomach or nose / nasopharynx depending on the clinical application site. BRIEF DESCRIPTION OF THE DRAWING

[0018] To clarify various aspects of some embodiments of the present invention, a more detailed description of the invention is given with reference to specific embodiments illustrated in the accompanying drawings. It is understood that these drawings represent only illustrated embodiments of the invention and are therefore not to be considered as limiting its scope. The invention is described and explained with additional specificity and detail using the accompanying drawings.

[0019] To make the advantages of the present invention easily understandable, a detailed description of the invention is given below in conjunction with the accompanying drawings, which, however, should not be regarded as limiting the scope of the invention to the accompanying drawings, in which: Fig. Figure 1 shows a schematic view of a biodegradable wireless in vivo dosimeter system (100) for monitoring radiotherapy. DETAILED DESCRIPTION

[0020] The present invention relates to a biodegradable wireless in vivo dosimetry system (100) for monitoring radiotherapy.

[0021] Fig. shows a detailed block diagram representation of a biodegradable wireless in vivo dosimetry system (100) for monitoring radiotherapy.

[0022] Although the present disclosure has been described with the purpose of a biodegradable wireless in vivo dosimeter system for monitoring radiotherapy, it should be noted that this is merely to illustrate the invention by way of example and to highlight other purposes or functions for which the described structures or configurations could be used and which fall within the scope of the present disclosure.

[0023] reference to Fig. 1 The biodegradable wireless dosimeter system (100) comprises the biodegradable wireless in vivo dosimeter unit (1) and the external reading unit (2), which are arranged to communicate via near-field coupling. The dosimeter unit (1) is configured to be temporarily placed in a body cavity at or near an area of ​​interest, such as the rectum, stomach, or nasopharynx, during radiotherapy, while the external reading unit (2) remains outside the patient, typically near the treatment table.

[0024] In the illustrated embodiment, the dosimeter unit (1) and the readout unit (2) are separated into blocks for better understanding and to facilitate the representation of a block diagram. Fig.1 in the form of functional blocks. It is understood that the blocks can be implemented using discrete circuits, integrated circuits or combinations thereof, and that certain blocks can be implemented in software or firmware, which can be implemented on a microcontroller or ASIC within the dosimeter unit (1) or the readout unit (2). Biodegradable wireless in vivo dosimeter unit (1)

[0025] The biodegradable wireless in vivo dosimeter unit (1) is a compact, adaptable device designed for direct exposure to the local radiation field. It is available in adaptable geometries such as a capsule, soft insert, band, or swallowable form. The geometry is selected according to the anatomical location and clinical workflow. The device has smooth, rounded contours to minimize friction and trauma during insertion and placement. Power Receiving and Rectifying Unit (PWR)

[0026] The dosimeter unit (1) comprises a power receiving and rectifying (PWR) block, which includes a near-field receiver (3) and a rectifier (4). The near-field receiver (3) includes a planar coil (10), which may be configured as a spiral or meander, together with an impedance matching network (11). The planar coil (10) and the matching network (11) are tuned to operate at a near-field communication (NFC) frequency of approximately 13.56 MHz or at a selected medical ISM band suitable for the implantation depth and regulatory requirements.

[0027] The planar coil (10) and the associated biodegradable conductors or compounds (5) are made of biodegradable metals such as magnesium, zinc, or their alloys, which are deposited or structured on a resorbable substrate (13) made, for example, of a bioresorbable polymer film. These metals gradually dissolve after the required monitoring period, thus contributing to the biodegradability of the device.

[0028] The rectifier (4) can be implemented using biodegradable or bioresorbable semiconductor structures, diodes, or equivalent circuits encapsulated within the device. The rectifier (4) converts the alternating voltage induced in the planar coil (10) into a direct current supply voltage, which is supplied to the downstream blocks. Energy buffer block (ENB)

[0029] The energy buffer block (ENB) comprises a biodegradable electrochemical energy buffer (6) configured as a Zn-ion hybrid micro-supercapacitor (7). The Zn-ion hybrid micro-supercapacitor (7) includes a zinc anode, a cathode based on a MoS2-containing or similar active material, and a biocompatible gel or polymer electrolyte, which may contain an alginate-based electrolyte or another bioresorbable medium.

[0030] The Zn-ion hybrid micro-supercapacitor (7) is electrically coupled to the rectifier (4) and smooths the rectified direct current, thus providing essentially ripple-free energy to the other blocks even during beam gating, gantry movement, or small displacements of the reading unit (2) relative to the dosimeter unit (1). This buffering enables stable operation of the sensor and telemetry circuits without the need for permanent batteries. Radiation measurement block (RSB)

[0031] The radiation measurement block (RSB) contains the radiation transduction module (8). The radiation transduction module (8) comprises either a scintillating nanocomposite material or a dosimetric polymer or a combination thereof, the response of which is essentially proportional to the absorbed dose over the clinically relevant dose and dose rate range.

[0032] The scintillating nanocomposite can generate optical photons in response to absorbed ionizing radiation, which are then converted into an electrical signal by a photodiode or other transducer. Alternatively, the dosimetric polymer can undergo changes in its electrical properties, which are measured directly. In both cases, the dose-proportional signal generated by the radiation transduction module (8) is fed to the telemetry and control block (TCB) (40) for further processing and telemetry. Physiological sensory block (PSB)

[0033] In certain embodiments, the dosimeter unit (1) includes an optional physiological sensor block (PSB). The PSB includes at least one additional physiological sensor (20), for example, a temperature sensor and a pH sensor. These sensors each measure the local tissue temperature and pH value.

[0034] Since the reaction of scintillation materials and dosimetric polymers can depend on temperature and local chemistry, the display of the physiological sensor block (PSB) can be used to apply compensation factors to the dose-proportional signal. The signals from the physiological sensors are sent together with the signal from the RSB to the telemetry and control block (TCB) (40). Telemetry and Control Block (TCB) (40)

[0035] The telemetry and control block (TCB) (40) is powered by the energy buffer block (ENB). The TCB (40) receives the dose-proportional signal from the radiation measurement block (RSB) and all sensor outputs from the physiological measurement block (PSB). It may contain amplification, filtering, analog-to-digital conversion, and modulation circuits.

[0036] In one embodiment, telemetry is achieved by load modulation of the near-field receiver (3), wherein the TCB (40) varies the load on the planar coil (10) to encode data in the current supplied by the external reading unit (2). Alternatively, the TCB (40) can use a backscatter modulation scheme or a separate low-power transmitter. The encoded telemetry transmits the measured radiation dose (via the signal) and optionally temperature and pH data to the external reading unit (2). Resorbable encapsulation block (9)

[0037] The internal blocks of the dosimeter unit (1) – including PWR, ENB, RSB, PSB and TCB (40) – are enclosed in a resorbable encapsulation block (9). The encapsulation block (9) comprises a multilayer polymer stack containing at least one layer of PLGA, PCL and silk fibroin or other combinations of biocompatible, biodegradable polymers.

[0038] The multi-layered architecture allows for adjustment of the device's functional lifespan. For example, the outermost layer can possess moisture barrier properties to stabilize the device in vivo for two to six weeks, after which water penetration gradually increases and the encapsulation begins to degrade. This controlled degradation time ensures that the device remains calibrated throughout the treatment period and that no surgical explantation is required.

[0039] Furthermore, the material stack and the geometry of the dosimeter unit (1) are designed to provide a stepwise resolution profile. After completion of the clinical monitoring phase, the temporary metallic conductors and connections (5) of the near-field receiver (3) begin to dissolve, thus interrupting energy transmission. Subsequently, the electrodes of the Zn-ion hybrid micro-supercapacitor (7) lose their conductivity, and finally, the polymer stack itself is degraded and resorbed. This stepwise process preserves the calibration during the monitoring period and ensures that no permanent metallic or rigid components remain. External reading unit (2)

[0040] The external reading unit (2) is configured to power the dosimeter unit (1), receive telemetry data, process the collected data and present dose information to clinical staff. Clutch and power transmission block (CPB)

[0041] The reading unit (2) comprises a coupling and power transfer block (CPB). The CPB contains a transmit / receive coil (35) and a power driver (41). The power driver (41) generates an RF or AC signal at the selected operating frequency (e.g., 13.56 MHz) that powers the transmit / receive coil (35). The coil (35) is positioned close to the patient such that its near field is efficiently coupled to the planar coil (10) of the dosimeter unit (1).

[0042] The same coil (35) or a separate receiving coil is used to detect the load modulation or backscatter from the dosimeter unit (1). The modulated signal transmits the telemetry data from the TCB (40), including the dose-proportional signal and all physiological sensor data. Signal Processing Block (SPB) (36)

[0043] The modulated signal from the CPB is forwarded to a signal processing block (SPB) (36). The SPB (36) demodulates and decodes the telemetry data to reconstruct numerical representations of the radiation dose and, if available, the temperature and pH.

[0044] The SPB (36) can contain digital filters, correction algorithms, and compensation lookup tables. The SPB (36) is also connected to the memory block (38), which stores device-specific calibration data, such as signal-to-absorbed dose relationships at different beam energies, field sizes, temperatures, and pH values. Memory block (38)

[0045] The memory block (38) can comprise non-volatile memory such as flash or EEPROM, or another suitable storage device. During device characterization in phantoms, calibration curves are generated and stored in the memory block (38). The SPB (36) accesses this data to convert the raw telemetry data into corrected values ​​for the absorbed dose.

[0046] The memory block (38) can also store historical, time-stamped dose logs (39) recorded over the duration of treatment sessions. These logs can be exported to external systems for documentation and analysis. User interface block (37)

[0047] A user interface block (37) is used to display the processed results to physicians. The user interface block (37) may include a screen, indicator lights, and user controls. The interface displays numerical dose values, dose-time graphs, and optionally a traffic light indicator that shows whether the device's measured dose is within, above, or below predefined tolerance ranges with respect to the treatment plan.

[0048] Additional user interface features may include alarms for missing telemetry data (indicating possible movement or dissolution of the device), notifications about the end of the monitoring period, and menus for selecting the anatomical placement type (rectal, gastric, nasal / nasopharyngeal) to apply site-specific calibration. Exemplary use in clinical workflow

[0049] During operation, the biodegradable wireless in vivo dosimeter unit (1) is prepared in the desired geometry – for example, as a rectal soft insert for radiotherapy of the prostate. Prior to treatment, the physician inserts the device into the body cavity and verifies its position using imaging or anatomical landmarks.

[0050] During treatment, the external reader (2) is placed near the patient so that the transmit / receive coil (35) is coupled to the planar coil (10) of the dosimeter unit (1). The power driver (41) supplies energy to the coil (35), and the PWR block of the dosimeter unit (1) receives and rectifies this energy, charging the Zn-ion hybrid micro supercapacitor (7) in the ENB block.

[0051] During irradiation, the radiation transduction module (8) in the RSB block generates the dose-proportional signal. This signal, along with all temperature and pH signals from the PSB block, is forwarded to the TCB (40), which encodes and transmits the telemetry data by modulating the load of the near-field receiver (3).

[0052] The CPB block of the external reading unit (2) detects these modulations and sends the received signal to the SPB (36). Using the calibration data stored in the memory block (38), the SPB (36) calculates corrected values ​​for the absorbed dose, which are then displayed by the Ul block (37) along with indications of whether the measured dose is within an acceptable range.

[0053] After completion of radiotherapy, the dosimeter unit (1) can either be naturally excreted from the body (in the case of gastrointestinal excretion) or remain in place to degrade. Over a period of several weeks, the temporarily present metals, the Zn-ion hybrid micro-supercapacitor (7), and the encapsulation block (9) are biologically resorbed, leaving only minimal residue. ADVANTAGES OF THE INVENTION

[0054] The present invention offers several advantages over existing dosimetry solutions, including, but not limited to: • The dosimeter unit (1) is biodegradable, so no surgical removal is required. • The system (100) is wireless, thus avoiding disruptive wiring and simplifying clinical workflows. • The Zn-ion hybrid micro-supercapacitor (7) provides a stable power supply without long-life batteries under dynamic treatment conditions. • The device can optionally measure temperature and pH to provide environment-compensated dose measurements. • The block diagram architecture simplifies integration and adaptation to different anatomical locations and treatment modalities. • The system enables real-time in-vivo verification of the delivered dose, thereby improving patient safety and treatment quality.

[0055] The figure and the preceding description provide examples of embodiments. Those skilled in the art will recognize that one or more of the described elements can be combined to form a single functional element. Alternatively, certain elements can be divided into several functional elements. Elements from one embodiment can be added to another embodiment ( ). For example, the sequence of the processes described here can be changed and is not limited to the manner described here. Furthermore, the actions of a block diagram need not be implemented in the sequence shown, nor does it necessarily have to be executed all actions. In addition, those actions that are not dependent on other actions can be executed in parallel with the other actions. The scope of embodiments is by no means limited by these specific examples.

[0056] Although the embodiments of the invention have been described in language relating to structural features and / or methods, it should be noted that the appended claims are not necessarily limited to the specific features or methods described. Rather, the specific features and methods are disclosed as examples of embodiments of the invention.

Claims

[1] A biodegradable wireless dosimetry system (100) for in vivo verification of radiotherapy, the system (100) comprising: a biodegradable wireless in vivo dosimeter unit (1); and an external reading unit (2) wirelessly coupled to the biodegradable wireless in vivo dosimeter unit (1); the biodegradable wireless in vivo dosimeter unit (1) comprises: a power receiving and rectifying unit (PWR) comprising a near-field receiver (3) and a rectifier (4) implemented with at least one biodegradable conductor or biodegradable compound (5), wherein the power receiving and rectifying unit (PWR) is configured to receive electromagnetic energy from the external reading unit (2) and generate a DC power supply; an energy buffer block (ENB) comprising a biodegradable electrochemical energy buffer (6) configured as a Zn-ion hybrid micro-supercapacitor (7), electrically coupled to the rectifier (4) and designed to stabilize the DC power supply during intermittent wireless coupling; a radiation sensor block (RSB) with a radiation transduction module (8) configured to generate a dose-proportional signal in response to absorbed ionizing radiation; an optional physiological sensor block (PSB) with at least one additional physiological sensor (20); a telemetry and control block (TCB) (40) configured to process the dose-proportional signal and all physiological sensor signals and to provide wireless telemetry to the external reading unit (2); and a resorbable encapsulation block (9) enclosing the near-field receiver (3), rectifier (4), energy buffer (6, 7), radiation transduction module (8), physiological auxiliary sensor (20) and telemetry and control block (40), wherein the resorbable encapsulation block (9) is configured to maintain the integrity of the device during a predefined clinical monitoring period and is subsequently biodegraded under physiological conditions; wherein the external reading unit (2) comprises a corresponding block diagram architecture: a coupling and power transfer block (CPB) with a transmit / receive coil (35) configured to couple with the near-field receiver (3) and to power the biodegradable wireless in vivo dosimeter unit (1); a signal processing block (SPB) (36) configured to demodulate and process telemetry data received from the telemetry and control block (40); a memory block (38) configured to store calibration data and measured dose information; and a user interface block (37) configured to display at least one parameter indicating the absorbed dose for verification of a radiotherapy plan, wherein the blocks (PWR, ENB, RSB, PSB, TCB, CPB, SPB, memory block (38) and user interface block (37)) are arranged such that a block diagram of the system (100) is defined by these functional units and their interconnections. [2] System (100) according to claim 1, wherein the near field receiver (3) of the power receiving and rectifying block (PWR) comprises a planar coil (10) and an impedance matching network (11) configured for operation at a near field communication frequency (NFC) around 13.56 MHz or at a medical industrial scientific medical (ISM) band selected according to an implantation depth of the biodegradable wireless in vivo dosimeter unit (1). [3] System (100) according to one of the preceding claims, wherein the energy buffer block (ENB) comprises the Zn-ion hybrid micro-supercapacitor (7) of the biodegradable electrochemical energy buffer (6), wherein the Zn-ion hybrid micro-supercapacitor (7) comprises: (i) a zinc anode; (ii) a cathode comprising a MoS2-based active material; and (iii) a biocompatible gel or polymer electrolyte comprising an alginate-based electrolyte; wherein the Zn-ion hybrid micro-supercapacitor (7) is dimensioned to provide a substantially wave-free supply voltage to the radiation measurement block (RSB), physiological measurement block (PSB) and telemetry and control block (TCB) during beam steering and movement of the gantry or couch. [4] System (100) according to one of the preceding claims, wherein the radiation measurement block (RSB) comprises the radiation transduction module (8) which contains a scintillation nanocomposite or a dosimetric polymer configured to convert absorbed ionizing radiation into an optical or electrical signal which is substantially linear to the dose over a clinical dose rate range relevant for external beam radiotherapy or brachytherapy. [5] System (100) according to one of the preceding claims, wherein the physiological sensor block (PSB) comprises at least one additional physiological sensor (20) selected from: - a temperature sensor configured to measure local tissue temperature; and - a pH sensor configured to measure the local tissue pH; and wherein the telemetry and control block (TCB) (40) is configured to combine the dose-proportional signal from the radiation measurement block (RSB) with the output signals of the physiological measurement block (PSB) to form telemetry data for the external reading unit (2). [6] System (100) according to any one of the preceding claims, wherein the resorbable encapsulation block (9) comprises a multilayer polymer stack containing at least one layer selected from poly(lactic acid-co-glycolic acid) (PLGA), poly(caprolactone) (PCL) and silk fibroin, wherein the multilayer polymer stack is designed to provide a functional lifetime in vivo of between 2 weeks and 6 weeks before substantial degradation, wherein the resorbable encapsulation block (9) is represented as an outer block surrounding the inner blocks of the biodegradable wireless in vivo dosimeter unit (1). [7] System (100) according to claim 1, wherein a material stack and the geometry of the biodegradable wireless in vivo dosimeter unit (1) are configured to provide a stepwise resolution profile, wherein: - the transient metal conductors of the near-field receiver (3) and the biodegradable conductor or biodegradable compound (5) dissolve after the predefined clinical monitoring window, - the electrodes of the Zn-ion hybrid micro-supercapacitor (7) subsequently lose their conductivity and - the resorbable encapsulation block (9) is subsequently degraded, thereby maintaining the calibration stability of the radiation measurement block (RSB) during the predefined clinical monitoring period, and wherein the stepwise resolution profile can be schematically represented as a sequence affecting the internal blocks of the dosimeter unit (1). [8] System (100) according to any one of the preceding claims, wherein the biodegradable wireless in vivo dosimeter unit (1) is formed in a compliant geometry selected from a capsule, a soft insert, a band or a swallowable shape with rounded edges and smooth surfaces, and is configured for anatomical placement selected from the following options: - rectal placement for external beam radiation therapy or brachytherapy of the prostate, - Placement in the stomach for radiation therapy of the upper gastrointestinal tract and - nasal or nasopharyngeal placement for radiotherapy of the head and neck region; and wherein the adaptable geometry is represented as a single block containing the internal functional blocks of the dosimeter unit (1). [9] System (100) according to any one of the preceding claims, wherein the external reading unit (2) is represented as comprising: the coupling and power transfer block (CPB) with the transmit / receive coil (35) and a power driver (41) configured to power the biodegradable wireless in vivo dosimeter unit (1) and receive telemetry data from the telemetry and control block (TCB) (40); the signal processing block (SPB) (36), which is configured to demodulate telemetry data from the biodegradable wireless in vivo dosimeter unit (1), apply device-specific calibration data stored in the memory block (38) and obtained from phantom measurements over a range of beam energies, field sizes, temperatures, and pH values, and calculate corrected values ​​for the absorbed dose; and the user interface block (37) which is configured to display numerical information on the absorbed dose and a traffic light warning indicating whether the measured dose values ​​are within, above or below predefined tolerance bands with respect to the radiotherapy plan, and optionally stores time-stamped dose logs (39), wherein the coupling and power transfer block (CPB), the signal processing block (SPB), the memory block (38) and the user interface block (37) are connected to form a clear block diagram representation of the external reading unit (2).

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