8 results about "Tissue phantom" patented technology

The present invention belongs to the technical field of radiotherapy quality control using an electronic portal imaging device, and discloses a quality control method based on an electronic portal imaging device and the maximum tissue phantom ratio. The digital reconstructed radiograph (DRR) image is improved by combining the maximum tissue phantom ratio (TMR) of the radiotherapy device to obtain a TMR-weighted DRR image; the TMR-weighted DRR image and the fluence map generated by the radiotherapy plan are used as data inputs to train an improved U-net network, and then a predicted EPID map is obtained; the predicted EPID map and the EPID map actually generated by the radiotherapy device are analyzed based on the gamma index, and the quality control of the radiotherapy device is carried out according to the gamma index. The present invention uses the maximum tissue phantom ratio data collected during the operation test of the device to convert the three-dimensional CT data into two-dimensional data, and the data needs to be collected additionally. Using an improved U-net network, a relatively high precision can be found after gamma analysis, and the positioning error during verification can be easily found and discriminated.

An optical tissue phantom (OTP) is provided, comprising: a matrix comprising a hot melt adhesive; and a light scattering agent and a light absorbing agent dispersed in the matrix. A method of forming the OTP is also provided.

Provided herein is technology relating to use of radiation for medical purposes and particularly, but not exclusively, to devices, systems, and methods for monitoring, testing, and maintenance of medical radiology equipment as part of a quality assurance program. For example, the technology provides, in part, systems and methods for calculating a tissue phantom ratio (TPR) used to characterize a beam.

The invention belongs to an evaluation method, and provides a method for simulating the influence of skin melanin distribution on PPG detection and a related device aiming at the technical problems that an existing skin melanin distribution simulation method cannot dynamically simulate melanin space distribution and does not have personalized distribution adjustment ability. The incident light interacting with the epidermal tissue phantom irradiates a melanin distribution simulation module, and transmission, reflection and scattered light interacting with gray level liquid crystal of simulated melanin are obtained; sequentially irradiating the obtained transmission light to a dermal tissue phantom and a subcutaneous tissue phantom to obtain transmission light generated after interaction with the subcutaneous tissue phantom and reflected light which sequentially and reversely penetrates through the dermal tissue phantom, the melanin simulation module and the epidermal tissue phantom and is reflected back to the incident end; the detection influence on the photoelectric volume pulse wave under the corresponding incident light signal is obtained and eliminated by detecting the light intensity ratio of the transmission light, the reflected light and the incident light.

Disclosed is a tissue phantom system, comprising: a tissue phantom material having known optical properties and an input surface for receiving incident source light from the optical measurement instrument; and one or more light guides having a first and second end, wherein the first end of the or each light guide is embedded within the phantom material at a respective location beneath the input surface to transmit light to and / or from the respective location for simulating an optical property variation within the tissue phantom material. Also disclosed is a method of calibrating or testing an optical measurement instrument configured to measure a target's response to illumination, by: illuminating the input surface of the tissue phantom material with source light, simulating an optical property variation within the tissue phantom material according to a known response pattern by transmitting light to and / or from the respective location beneath the input surface via the one or more light guides; and detecting scattered light emitted from the tissue phantom material.

Disclosed in the present application are a tissue-mimicking phantom material for needle insertion and a preparation method therefor. The tissue-mimicking phantom material is an aqueous gel, and comprises the following raw materials in percentages by mass: 0.2%-0.8% of sodium carboxymethyl cellulose, 0.05%-0.5% of xanthan gum, 0.2%-1.5% of carrageenans, 7%-12% of agar, and 0.2%-1% of a preservative, with the balance being purified water. The preparation method comprises: (1) uniformly mixing the raw materials; (2) heating the resulting mixture and maintaining same at 90-100°C for 30-60 min; and (3) cooling the mixture to obtain a tissue-mimicking phantom material for needle insertion. Further disclosed is a tissue-mimicking phantom for needle insertion, the phantom comprising an outer frame, simulated skin, a tissue-mimicking phantom material, a simulated lesion and a sound-absorbing material. The tissue-mimicking phantom for needle insertion has the advantages of being capable of simulating a lesion in a human body, providing clear imaging and having a sound velocity consistent with that of the human body; capable of allowing multiple needle insertions and realizing real-time observation of insertion paths and results; effectively improving the insertion proficiency of physicians, and shortening the learning path; etc.

A method for calibrating detectors of a self-contained, tissue oximetry device includes emitting light from a light source into a tissue phantom, detecting in a plurality of detectors the light emitted from the light source, subsequent to reflection from the tissue phantom, and generating a set of detector responses by the plurality of detectors based on detecting the light emitted from the light source. The method further includes determining a set of differences between the set of detector responses and a reflectance curve for the tissue phantom, and generating a set of calibration functions based on the set of differences. Each calibration function in the set of calibration functions is associated with a unique, light source-detector pair. The method further includes storing the set of calibration function in a memory of the self-contained, tissue oximetry device.