Portable bedside temperature monitoring device based on magnetic resonance and use method

Abstract

The invention discloses a portable bedside temperature monitoring device based on magnetic resonance and a use method, and belongs to the technical field of medical imaging and treatment monitoring. The device consists of an ultrasonic treatment module, a magnetic resonance imaging module, a data acquisition and temperature reconstruction module, an energy feedback and control module and a control host, wherein the ultrasonic treatment module is used for heating or ablating target tissues in a body; the magnetic resonance imaging module collects magnetic resonance signals in real time and carries out temperature distribution imaging. The data acquisition and temperature reconstruction module receives and processes the ultrasonic energy parameter and the magnetic resonance signal to generate a temperature field image; the energy feedback and control module is used for adjusting and controlling; and the control host completes data interaction control among the modules. According to the device, bedside real-time temperature monitoring is achieved through portable magnetic resonance, and risks caused by a patient transfer process in a traditional method are avoided; compared with a traditional method, it is ensured that the target area can be stably maintained in an effective treatment temperature window, and the treatment efficiency is improved.

Description

Technical Field

[0001] This invention relates to a portable bedside temperature monitoring device based on magnetic resonance imaging and its usage method, belonging to the field of medical imaging and treatment monitoring technology. Background Technology

[0002] Currently, hyperthermia therapies such as ultrasound-enhanced drug release and laser heating are widely studied and applied in fields such as oncology, breast diseases, and neuromodulation. However, real-time and quantitative monitoring of the treatment area temperature remains a key bottleneck limiting its safety and controllability. Common temperature monitoring methods include infrared thermography, thermocouple probes, and B-mode ultrasound echo change analysis, but these methods all have the following drawbacks: 1) They cannot accurately reflect changes in deep tissue temperature; 2) They have low spatial resolution and are easily affected by sound attenuation, bubbles, or scattering; 3) Precise temperature control feedback is difficult to achieve. Magnetic resonance thermography can achieve quantitative imaging of tissue temperature through phase drift or T1 change methods, and is currently a better method for accurately monitoring deep tissue temperature rise. However, traditional magnetic resonance systems are bulky, expensive, complex to operate, and have high environmental requirements, limiting them to fixed treatment centers and failing to meet the real-time monitoring needs of bedside, intraoperative, and mobile settings.

[0003] In precision interventional treatments such as laser radiofrequency ablation, ultrasound thermotherapy, and ultrasound-sensitive drug delivery, doctors urgently need a device that can display temperature distribution in real time at the operating table to achieve non-invasive temperature field imaging, immediate feedback and adjustment of treatment energy, and reduction of tissue overheating and damage to adjacent structures. Therefore, there is a pressing need for a miniaturized, low-magnetic-field, portable magnetic resonance temperature monitoring system to work in conjunction with ultrasound or radiofrequency treatment equipment to achieve real-time thermal feedback and closed-loop energy control. Summary of the Invention

[0004] The technical problem that the invention aims to solve

[0005] This invention addresses the problem of inconvenient temperature monitoring in the field of thermotherapy by proposing a portable bedside temperature monitoring device based on magnetic resonance imaging and its usage method.

[0006] Technical solution

[0007] To achieve the above objectives, the technical solution provided by the present invention is as follows:

[0008] A portable bedside temperature monitoring device based on magnetic resonance imaging (MRI) comprises an ultrasound therapy module, an MRI module, a data acquisition and temperature reconstruction module, an energy feedback and control module, and a control host. The ultrasound therapy module generates and focuses ultrasound energy to heat or ablate target tissue within the body. The MRI module acquires MRI signals from the target area in real time during heating and performs temperature distribution imaging. The data acquisition and temperature reconstruction module receives and processes ultrasound energy parameters and MRI signals, calculates tissue temperature based on MRI phase changes or relaxation time changes, and generates a temperature field image. The energy feedback and control module adjusts and controls the transmission power, frequency, and duration of the ultrasound therapy module based on the temperature field reconstructed by the data acquisition and temperature reconstruction module. The control host performs data interaction control between modules, displays the temperature field image, and sends device control commands through an interface.

[0009] Furthermore, the ultrasound therapy module includes an ultrasound transducer, a power amplifier and signal driving unit, a coupling medium, and a positioning device. The ultrasound transducer converts electrical signals into ultrasound signals, which are then applied to the target area to produce a temperature increase effect. The power amplifier and signal driving unit generate high-frequency ultrasound driving signals to drive the ultrasound transducer; the driving signal parameters can be adjusted by the control host. The coupling medium allows the ultrasound transducer to contact the body surface to achieve information acquisition from the target area. The positioning device is connected to the ultrasound transducer to adjust its spatial position.

[0010] Another embodiment of the device of the present invention comprises a laser therapy module, an interventional fiber optic transmission module, a magnetic resonance imaging module, a data acquisition and temperature reconstruction module, an energy feedback and control module, and a control host. The laser therapy module is used to generate controllable light energy as a heating energy source and consists of a laser emitting unit, a power control driver, a cooling device, and a positioning device. The laser emitting unit is used to emit laser light towards the target area, the power control driver is used to control the laser emission power, the cooling device ensures the module temperature is stable and prevents the device temperature from becoming too high, and the positioning device is used for position calibration during the treatment process.

[0011] Furthermore, the laser therapy module consists of a laser emitting unit, a power control driver, a cooling device, and a positioning device. The laser emitting unit is used to emit laser light towards the target area, the power control driver is used to control the laser emission power, the cooling device ensures the module temperature is stable and prevents the device temperature from becoming too high, and the positioning device is used for position calibration during the treatment process.

[0012] Furthermore, the interventional fiber optic transmission module is used to precisely transmit laser energy to the target area. It includes a main transmission fiber, an interventional guide needle, and a terminal diffusion probe. One end of the main transmission fiber is connected to the laser source via a coupler, and the other end is inserted into the lesion area via the interventional guide needle to achieve local irradiation; the terminal diffusion probe is equipped with a diffuser or a spherical microlens to achieve uniform light energy distribution.

[0013] Furthermore, the magnetic resonance imaging module includes a permanent magnet, a gradient coil, a radio frequency (RF) unit, and an imaging sequence control unit. Specifically: the permanent magnet generates and maintains a static main magnetic field for magnetic resonance imaging; the gradient coil generates a linearly varying gradient magnetic field along the three-dimensional coordinate axes, which superimposes on the static main magnetic field generated by the permanent magnet, giving atomic nuclei at different spatial locations in the imaging space differentiated resonance frequencies or phases, providing spatial positioning information for image reconstruction; the RF unit includes an RF transmitting section and an RF receiving section, wherein the RF transmitting section generates RF pulses of a specific frequency, transferring energy to the magnetized atomic nuclei, causing their net magnetization vector to deflect, thereby exciting the nuclear magnetic resonance phenomenon; the RF receiving section detects and receives the magnetic resonance signals radiated by the excited atomic nuclei during relaxation during the RF pulse transmission intervals; the imaging sequence control unit sends timing control commands to the gradient coil within the magnetic resonance imaging module and the RF transmitting unit within the RF unit, synchronously triggering the RF receiving unit to acquire magnetic resonance signals.

[0014] Furthermore, the device is equipped with a portable stand and casters at the bottom, allowing it to be moved to the patient's bedside.

[0015] The method of using a portable bedside temperature monitoring device based on magnetic resonance includes the following steps:

[0016] Step 1, the planning phase, involves acquiring target information using a magnetic resonance imaging module, including the following steps:

[0017] Step 1-1: Adjust the positions of the magnetic resonance module and the ultrasound / laser therapy module so that the focus of the ultrasound transducer / laser emitting unit is aligned with the patient's target area. Then, the ultrasound / laser therapy module positioning device fixes the treatment area.

[0018] Steps 1-2: The radio frequency unit in the magnetic resonance module of the device emits radio frequency pulses to the imaging area, and the gradient coil generates a gradient magnetic field and applies it to the imaging area.

[0019] Steps 1-3: The data acquisition and temperature reconstruction module acquires and processes the magnetic resonance signal, reconstructing the magnetic resonance signal into a visible temperature image;

[0020] Steps 1-4: Based on the temperature images from Steps 1-3, obtain the three-dimensional position, shape, and volume information of the target point.

[0021] Step 2, the treatment phase, involves pre-setting initial parameters for the ultrasound / laser treatment module based on the target area information obtained in Step 1 (pre-operative planning phase) and controlling the heating process. This mainly includes the following steps:

[0022] Step 2-1: Based on the target area information obtained in Step 1, set the ultrasonic / laser focusing point and target temperature;

[0023] Step 2-2: Start the ultrasound / laser therapy module and the magnetic resonance imaging module to perform thermal therapy. At the same time, the data acquisition and temperature reconstruction module acquires magnetic resonance signals, reconstructs the temperature field of the target area based on the magnetic resonance phase difference, and feeds back the temperature field information to the energy feedback and control module.

[0024] Step 2-3: The energy feedback and control module receives the temperature field information of the target area and automatically adjusts the output of the ultrasound / laser therapy module according to the preset target temperature in step 2-1 to achieve constant temperature or gradual heating control. When the temperature of the target area reaches the preset heat dose, the ultrasound / laser therapy module is controlled to reduce the irradiation power until the energy output is automatically stopped at the end of the treatment.

[0025] Step 3, the evaluation phase, involves performing steps 1-1 to 1-4 using the device to evaluate the extent of tissue damage in the target area using magnetic resonance imaging.

[0026] Beneficial effects

[0027] The device of this invention enables real-time bedside temperature monitoring through portable magnetic resonance imaging, solving the problem that traditional magnetic resonance equipment cannot enter the intensive care unit or operating room for real-time monitoring, and avoiding the risks brought about by the patient transfer process of traditional methods; real-time non-destructive temperature measurement can effectively prevent tissue carbonization or thermal burns caused by excessive local temperature rise during laser or radiofrequency heating, significantly improving the safety of bedside treatment.

[0028] The device and related usage methods of this invention establish an integrated and precise closed-loop control mechanism of "monitoring-feedback-execution". It can dynamically adjust the ultrasound treatment parameters and laser power according to the temperature distribution map of real-time magnetic resonance feedback. Compared with the traditional method of setting the heating power based on experience in hyperthermia, it ensures that the target lesion area can be stably maintained within the effective treatment temperature window, thus improving treatment efficiency. Attached Figure Description

[0029] Figure 1 This is a diagram showing the device composition of Embodiment 1 of the present invention;

[0030] Figure 2 This is a diagram showing the device composition of Embodiment 2 of the present invention;

[0031] Figure 3 This is a flowchart of the application method of the device of the present invention. Detailed Implementation

[0032] To further understand the content of this invention, it will be described in detail with reference to the accompanying drawings and specific embodiments.

[0033] This invention utilizes magnetic resonance thermometry (MRT) technology to achieve non-invasive imaging and quantitative measurement of local temperature rises through temperature-dependent changes in tissue signals. Magnetic resonance temperature measurement is primarily based on the following two principles:

[0034] 1. Phase Shift Method (Proton Resonance Frequency Shift, PRFS)

[0035] The resonance frequency of hydrogen protons (mainly those in water) shifts linearly with increasing temperature. As temperature rises, hydrogen bonds break, and the electron cloud structure around water molecules undergoes slight changes, thus shielding the protons from the local magnetic field and altering the actual magnetic field strength they experience. In a weak magnetic field environment, the proton resonance frequency changes linearly with temperature, and this relationship can be expressed as:

[0036] (1)

[0037] in Let α be the phase change, γ be the proton gyromagnetic ratio, B0 be the principal magnetic field strength, α be the water proton chemical shift temperature coefficient (approximately −0.01 ppm / °C), TE be the echo time, and T0 be the reference temperature. From the above equation, it can be seen that as the temperature increases (ΔT = T - T0 > 0), the resonant frequency decreases, leading to a phase shift. It is negative, and the phase shift is also negative. The temperature change is proportional to the temperature change ΔT. Therefore, by measuring the phase change, the temperature change of each pixel can be directly and quantitatively calculated. By continuously acquiring phase images at different time points and subtracting them, the pixel-level temperature change distribution can be obtained, thus generating a temperature field image.

[0038] 2. Relaxation Time Method

[0039] The longitudinal relaxation time of human tissue is positively correlated with temperature. As temperature increases, the thermal motion of water molecules intensifies, reducing the efficiency of their interaction with the surrounding crystal lattice. This slows down the rate at which protons recover from a high-energy state to a low-energy state (relaxation), thus prolonging the longitudinal relaxation time T1. T1 can be fitted using multi-point sampling.

[0040] (2)

[0041] Where T1(T) represents the longitudinal relaxation time measured or calculated at temperature T, T1,0 T1 represents the longitudinal relaxation time measured at the reference baseline temperature T0, which is the benchmark for all temperature calculations; T0 represents the reference baseline temperature, which is usually selected as the steady-state temperature in the body before treatment (such as 37°C) or a known room temperature; k is the tissue-specific temperature coefficient, which is an empirical constant. The sign of the value of k determines whether T1 is prolonged or shortened as the temperature increases.

[0042] The relaxation time method is effective for adipose tissue and insensitive to magnetic fields, thus overcoming the shortcomings of the phase drift method. The device of this invention, through the combined use of these two modes, can achieve bedside temperature monitoring with a spatial resolution of 2 mm and a temperature accuracy of ±1℃ in a low magnetic field environment.

[0043] Example 1

[0044] The device of the present invention is composed as follows Figure 1 As shown, it consists of an ultrasound therapy module, a magnetic resonance imaging module, a data acquisition and temperature reconstruction module, an energy feedback and control module, and a control host. Among them:

[0045] The ultrasound therapy module generates and focuses ultrasound energy to heat or ablate target tissues within the body; the magnetic resonance imaging module acquires magnetic resonance signals from the target area in real time during heating and performs temperature distribution imaging; the data acquisition and temperature reconstruction module receives and processes ultrasound energy parameters and magnetic resonance signals, calculates tissue temperature based on magnetic resonance phase changes or T1 relaxation time changes, and generates a temperature field image; the energy feedback and control module adjusts and controls the transmission power, frequency, and duration of the ultrasound therapy module based on the temperature field reconstructed by the data acquisition and temperature reconstruction module; and the control host completes data interaction control between modules, displays temperature field images, and sends device control commands through the interface.

[0046] The ultrasound therapy module includes an ultrasound transducer, a power amplifier and signal drive unit, a coupling medium, and a positioning device. The ultrasound transducer converts electrical signals into ultrasound signals, which are then applied to the target area to produce a temperature increase. The power amplifier and signal drive unit generate high-frequency ultrasound drive signals to drive the ultrasound transducer. The drive signal parameters can be adjusted via a control unit; in this embodiment, the drive signal parameters include frequency, duty cycle, pulse repetition period, treatment time, and acoustic power. The coupling medium allows the ultrasound transducer to contact the body surface for information acquisition from the target area. The positioning device is connected to the ultrasound transducer to adjust its spatial position. The positioning device employs a robotic arm or a three-dimensional sliding rail structure, with a positioning marker at its end for position calibration in magnetic resonance imaging.

[0047] The magnetic resonance imaging (MRI) module includes a permanent magnet, gradient coils, a radio frequency (RF) unit, and an imaging sequence control unit. The module employs a low-field, open-structure design, allowing for bedside placement. The MRI module primarily utilizes phase-shift imaging for temperature-sensitive imaging, and can be further combined with T1 relaxation time imaging to aid in assessing the extent of thermal damage.

[0048] In the magnetic resonance imaging (MRI) module, a permanent magnet generates and maintains a static main magnetic field for MRI. Gradient coils generate linearly varying gradient magnetic fields along the three-dimensional coordinate axes, which are superimposed on the static main magnetic field generated by the permanent magnet. This results in atomic nuclei at different spatial locations in the imaging space having differentiated resonance frequencies or phases, providing spatial positioning information for image reconstruction. The gradient magnetic field strength, timing, and switching logic of the gradient coils are controlled by the imaging sequence control unit. The radio frequency (RF) unit includes an RF transmitting section and an RF receiving section. The RF transmitting section generates RF pulses of a specific frequency, transferring energy to the magnetized atomic nuclei, causing a deflection of their net magnetization vector and thus exciting nuclear magnetic resonance (NMR). The RF receiving section detects and receives the weak magnetic resonance signals radiated by the excited atomic nuclei during relaxation during the RF pulse transmission intervals. The imaging sequence control unit sends timing control commands to the gradient coils within the MRI module and the RF transmitting unit within the RF unit, synchronously triggering the RF receiving unit to acquire magnetic resonance signals.

[0049] The data acquisition and temperature reconstruction module receives and processes the magnetic resonance signal from the magnetic resonance imaging module, and converts the original magnetic resonance signal into a visible temperature image. The data acquisition unit first acquires and processes the original magnetic resonance signal data, and then the temperature reconstruction unit calculates the difference between the phase maps of adjacent time points to obtain the pixel-level phase change Δφ. The relationship between the pixel phase difference Δφ and the reference temperature T0 is calculated using the aforementioned equation (1) to obtain the temperature change. It generates real-time temperature field images. When the monitored target is tissue such as fat, the device can switch to a temperature measurement mode based on T1 relaxation time. In this mode, the temperature reconstruction module calculates the temperature and generates a temperature field image based on a pre-calibrated linear relationship model between T1 value and temperature.

[0050] The energy feedback and control module enables closed-loop regulation of magnetic resonance temperature imaging and ultrasonic power control. The module acquires the temperature change information ΔT from the temperature reconstruction unit and the set target temperature T. target Compare them. If ΔT < T target If ΔT ≥ T, then increase the ultrasonic power of the ultrasonic therapy module or prolong the ultrasonic treatment time; targetIf the temperature exceeds the safe range or an abnormal physiological signal is detected, the ultrasonic power of the ultrasound therapy module will be reduced or the ultrasound output will be stopped. The control algorithm of the module can be proportional-integral-derivative (PID) control, fuzzy control, or model predictive control (MPC). The module can be set with multiple safety thresholds and will automatically cut off power when the temperature exceeds the safe range or when an abnormal physiological signal is detected.

[0051] The control unit includes a user interface, a main control unit, and a storage unit. Users can load MRI structural images on the graphical interface, select target and protected areas, and set the treatment temperature, heating time, and scan trajectory. The system can display temperature field isotherms, heat dose distribution, and energy output status in real time. Data can be stored in DICOM format and connected to the hospital information system.

[0052] Example 2

[0053] As another embodiment of this device, it can be used for temperature monitoring and control during minimally invasive laser ablation treatment. Under the guidance and monitoring of magnetic resonance imaging, it can achieve precise laser heating treatment of target tissues in the body. It is suitable for minimally invasive thermal ablation and thermoregulation of tumors, fibrosis or lesions.

[0054] Figure 2 The diagram shows the structural composition of the device, which includes a laser therapy module, an interventional fiber optic transmission module, a magnetic resonance imaging module, a data acquisition and temperature reconstruction module, an energy feedback and control module, and a control host. The magnetic resonance imaging module, the data acquisition and temperature reconstruction module, the energy feedback and control module, and the control host have the same composition and function as those in Example 1.

[0055] The laser therapy module in the device generates controllable light energy as a heating energy source. It consists of a laser emitting unit, a power control driver, a cooling device, and a positioning device. The laser emitting unit emits laser light towards the target area, the power control driver controls the laser emission power, the cooling device ensures stable module temperature and prevents overheating, and the positioning device is used for position calibration during treatment. In this embodiment, the laser emitting unit uses a semiconductor laser array in the 980–1064 nm wavelength band, which matches the absorption peaks of water and hemoglobin in human soft tissue, enabling efficient local photothermal conversion. The laser source output power is adjustable and supports both continuous and pulsed modes. The power control driver uses a constant current drive mode, and the cooling device uses a water-cooling + TEC dual-mode. The entire laser therapy module is encapsulated in non-magnetic aluminum alloy and polymer materials, meeting the requirements for use in a magnetic resonance environment.

[0056] The interventional fiber optic transmission module is used to precisely transmit laser energy to the target area. It includes a main transmission fiber, an interventional guide needle, and a terminal diffusion probe. The main fiber is made of low-loss silica fiber with a polyimide sheath, and its length is customized according to the target area. The fiber is connected to the laser source via a coupler, and the other end is inserted into the lesion area via the interventional guide needle to achieve local irradiation. The terminal diffusion probe is equipped with a diffuser or a spherical microlens to achieve uniform light energy distribution. The outer layer of the guide needle has magnetic resonance imaging (MRI) marker lines for real-time MRI tracking of the position.

[0057] The main principle behind the dynamic adaptive adjustment of therapeutic energy by the energy feedback and control module is as follows: After each magnetic resonance data acquisition, the data acquisition and temperature reconstruction module generates a three-dimensional temperature distribution matrix T(x,y,z,t) at time t, and compares it with the target temperature field T established during the planning phase. target Compare (x, y, z) and calculate the deviation value:

[0058] (3)

[0059] When the local temperature deviation exceeds the set threshold, feedback control is triggered.

[0060] Real-time calculation of energy adjustment based on PID (proportional-integral-derivative) or model predictive control (MPC) algorithms:

[0061] (4)

[0062] Where P old P represents the energy output power before adjustment. new K represents the adjusted energy output power. p K i K d The corresponding control signals, which are used to control parameters, are fed back to the power amplifier (Example 1) or the power control driver (Example 2) in real time.

[0063] like Figure 3 As shown, the method of using the portable bedside temperature monitoring device based on magnetic resonance of the present invention includes the following steps:

[0064] Step 1, the planning phase, involves acquiring target information using a magnetic resonance imaging module, including the following steps:

[0065] Step 1-1: Adjust the positions of the magnetic resonance module and the ultrasound / laser therapy module so that the focus of the ultrasound transducer / laser emitting unit is aligned with the patient's target area. Then, the ultrasound / laser therapy module positioning device fixes the treatment area.

[0066] Steps 1-2: The radio frequency unit in the magnetic resonance module of the device emits radio frequency pulses to the imaging area, and the gradient coil generates a gradient magnetic field and applies it to the imaging area.

[0067] Steps 1-3: The data acquisition and temperature reconstruction module acquires and processes the magnetic resonance signal, reconstructing the magnetic resonance signal into a visible temperature image;

[0068] Steps 1-4: Based on the temperature images from Steps 1-3, obtain the three-dimensional position, shape, and volume information of the target point.

[0069] Step 2, the treatment phase, involves pre-setting initial parameters for the ultrasound / laser treatment module based on the target area information obtained in Step 1 (pre-operative planning phase) and controlling the heating process. This mainly includes the following steps:

[0070] Step 2-1: Based on the target area information obtained in Step 1, set the ultrasonic / laser focusing point and target temperature;

[0071] Step 2-2: Start the ultrasound / laser therapy module and the magnetic resonance imaging module to perform thermal therapy. At the same time, the data acquisition and temperature reconstruction module acquires magnetic resonance signals, reconstructs the temperature field of the target area based on the magnetic resonance phase difference, and feeds back the temperature field information to the energy feedback and control module.

[0072] Step 2-3: The energy feedback and control module receives the temperature field information of the target area and automatically adjusts the output of the ultrasound / laser therapy module according to the preset target temperature in step 2-1 to achieve constant temperature or gradual heating control. When the temperature of the target area reaches the preset heat dose, the ultrasound / laser therapy module is controlled to reduce the irradiation power until the energy output is automatically stopped at the end of the treatment.

[0073] Step 3, the evaluation phase, involves performing steps 1-1 to 1-4 using the device to evaluate the extent of tissue damage in the target area using magnetic resonance imaging.

[0074] The present invention and its embodiments have been described above illustratively. This description is not restrictive, and the figures shown are only one embodiment of the present invention; the actual structure is not limited thereto. Therefore, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the present invention, such designs should fall within the protection scope of the present invention.

Claims

1. A magnetic resonance based portable bedside temperature monitoring device, characterized in that, The device comprises an ultrasound therapy module, a magnetic resonance imaging module, a data acquisition and temperature reconstruction module, an energy feedback and control module, and a control host. The ultrasound therapy module generates and focuses ultrasound energy to heat or ablate target tissues within the body. The magnetic resonance imaging module acquires magnetic resonance signals from the target area in real time during the heating process and performs temperature distribution imaging. The data acquisition and temperature reconstruction module receives and processes ultrasound energy parameters and magnetic resonance signals, calculates tissue temperature based on magnetic resonance phase changes or relaxation time changes, and generates a temperature field image. The energy feedback and control module adjusts and controls the transmission power, frequency, and action time of the ultrasound therapy module based on the temperature field reconstructed by the data acquisition and temperature reconstruction module. The control host performs data interaction control between the modules, displays the temperature field image, and sends device control commands through the interface.

2. A portable, bedside, magnetic resonance-based temperature monitoring device as defined in claim 1, wherein, The ultrasound therapy module includes an ultrasound transducer, a power amplifier and signal driving unit, a coupling medium, and a positioning device. The ultrasound transducer converts electrical signals into ultrasound signals and applies them to the target area, producing a temperature increase effect. The power amplifier and signal driving unit generate high-frequency ultrasound driving signals to drive the ultrasound transducer, and the driving signal parameters can be adjusted by the control host. The coupling medium is used for the ultrasound transducer to contact the body surface to achieve information acquisition of the target area. The positioning device is connected to the ultrasound transducer to adjust the spatial position of the transducer.

3. A magnetic resonance based portable bedside temperature monitoring device, characterized in that, The system comprises a laser therapy module, an interventional fiber optic transmission module, a magnetic resonance imaging module, a data acquisition and temperature reconstruction module, an energy feedback and control module, and a control host. The laser therapy module generates controllable light energy as a heating energy source. The interventional fiber optic transmission module precisely transmits laser energy to the target area. The data acquisition and temperature reconstruction module receives and processes ultrasound energy parameters and magnetic resonance signals, calculates tissue temperature based on magnetic resonance phase changes or relaxation time changes, and generates a temperature field image. The energy feedback and control module adjusts and controls the emission power, frequency, and action time of the ultrasound therapy module based on the temperature field reconstructed by the data acquisition and temperature reconstruction module. The control host performs data interaction control between the modules, displays the temperature field image, and sends device control commands through the interface.

4. A portable bedside temperature monitoring device based on magnetic resonance as described in claim 3, characterized in that, The laser treatment module consists of a laser emitting unit, a power control driver, a cooling device, and a positioning device. The laser emitting unit is used to emit laser light towards the target area. The power control driver is used to control the laser emission power. The cooling device ensures the module temperature is stable and prevents the device temperature from becoming too high. The positioning device is used for position calibration during the treatment process.

5. A portable bedside temperature monitoring device based on magnetic resonance as described in claim 3, characterized in that, The interventional fiber optic transmission module includes a main transmission fiber, an interventional guide needle, and an end diffusion probe. One end of the main transmission fiber is connected to a laser source via a coupler, and the other end is inserted into the lesion area via the interventional guide needle to achieve local irradiation. The end diffusion probe is equipped with a diffuse probe or a spherical microlens to achieve uniform light energy distribution.

6. A portable bedside temperature monitoring device based on magnetic resonance as described in any one of claims 1 or 3, characterized in that, The magnetic resonance imaging module includes a permanent magnet, gradient coils, a radio frequency (RF) unit, and an imaging sequence control unit. The permanent magnet generates and maintains a static main magnetic field for magnetic resonance imaging. The gradient coils generate a linearly varying gradient magnetic field on the three-dimensional coordinate axes, which is superimposed on the static main magnetic field generated by the permanent magnet, so that atomic nuclei at different spatial locations in the imaging space have differentiated resonance frequencies or phases, providing spatial positioning information for image reconstruction. The RF unit includes an RF transmitting section and an RF receiving section. The RF transmitting section generates RF pulses of a specific frequency, which transfer energy to the magnetized atomic nuclei, causing their net magnetization vector to deflect, thereby exciting the nuclear magnetic resonance phenomenon. The RF receiving section detects and receives the magnetic resonance signals radiated by the excited atomic nuclei during the relaxation process during the intervals between RF pulse transmissions. The imaging sequence control unit sends timing control commands to the gradient coil in the magnetic resonance imaging module and the radio frequency transmitting unit in the radio frequency unit, synchronously triggering the radio frequency receiving unit to acquire magnetic resonance signals.

7. A portable bedside temperature monitoring device based on magnetic resonance as described in claim 6, characterized in that, The device is equipped with a portable stand and casters at the bottom, allowing it to be moved to the patient's bedside.

8. A method of using the portable bedside temperature monitoring device based on magnetic resonance as described in claim 7, characterized in that, Includes the following steps: Step S1, the planning phase, involves acquiring target information through a magnetic resonance imaging module, including the following steps: Step S1-1: Adjust the positions of the magnetic resonance module and the ultrasound / laser therapy module so that the focal point of the ultrasound transducer / laser emitting unit is aligned with the patient's target area, and then fix the treatment area with the ultrasound / laser therapy module positioning device. In steps S1-2, the radio frequency unit in the magnetic resonance module of the device transmits radio frequency pulses to the imaging area, and the gradient coil generates a gradient magnetic field and applies it to the imaging area. Steps S1-3: The data acquisition and temperature reconstruction module acquires and processes the magnetic resonance signal, and reconstructs the magnetic resonance signal into a visible temperature image. Step S1-4: Based on the temperature image from step S1-3, obtain the three-dimensional position, shape, and volume information of the target point; Step 2, the treatment phase, involves pre-setting initial parameters for the ultrasound / laser treatment module based on the target area information obtained in the preoperative planning phase of step S1, and controlling the heating process. This mainly includes the following steps: Step S2-1: Based on the target area information obtained in step S1, set the ultrasonic / laser focusing point and the target temperature; Step S2-2: The ultrasound / laser therapy module and the magnetic resonance imaging module are activated to perform thermal therapy. At the same time, the data acquisition and temperature reconstruction module acquires magnetic resonance signals, reconstructs the temperature field of the target area based on the magnetic resonance phase difference, and feeds back the temperature field information to the energy feedback and control module. In step S2-3, the energy feedback and control module receives the temperature field information of the target area and automatically adjusts the output of the ultrasound / laser therapy module according to the preset target temperature in step S2-1 to achieve constant temperature or gradual heating control. When the temperature of the target area reaches the preset heat dose, the ultrasound / laser therapy module is controlled to reduce the irradiation power until the energy output is automatically stopped after the treatment ends. Step S3, the evaluation stage, involves performing steps S1-1 to S1-4 using the device to evaluate the extent of tissue damage in the target area using magnetic resonance imaging.

Images