36 results about "Reference dose" patented technology

A computer-based method for generating an improved radiation therapy treatment plan for a treatment volume having a target and an organ-at-risk. The method includes a step of accessing an existing radiation therapy treatment plan from a memory of a computer, a dose distribution of the existing radiation therapy treatment plan serving as a reference dose distribution; and performing machine parameter optimization on the existing radiation therapy treatment plan with the computer by pursuing an optimization goal to minimize doses to the organ-at-risk, thereby generating the improved radiation therapy treatment plan.

An X-ray imaging apparatus includes an estimation unit (208) that estimates a cumulative exposure dose of X-rays irradiated onto an object, a remaining exposure tolerance dose calculation unit (213) that calculates a remaining exposure tolerance dose using a difference between a tolerated maximum exposure dose and the cumulative exposure dose, an X-ray irradiation tolerance period calculation unit (206) that calculates an X-ray irradiation tolerance period using a difference between a predetermined scheduled X-ray irradiation period and an actual irradiation period of X-rays irradiated onto the object, an X-ray irradiation reference dose calculation unit (212) that calculates an X-ray irradiation reference dose per unit time that will form a basis of X-ray irradiation based on the remaining exposure tolerance dose and the X-ray irradiation tolerance period, and a control unit (211) that controls X-ray irradiation onto the object by setting an X-ray irradiation dose per unit time within the X-ray irradiation tolerance period based on the X-ray irradiation reference dose.

An X-ray CT apparatus that transmits X-rays toward a subject on the basis of a set scan condition and reconstructs images from detected X-rays that passes through the subject, including a scan plan setting unit configured to set the scan condition, a reference dose storage unit configured to store reference dose information, including an relation between an attribute information about a plurality of kinds of subjects and reference doses to be referenced for an exposure dose, and an exposure dose calculation unit configured to calculate the exposure dose corresponding to the set scan condition in accordance with the timing of setting of the scan condition.

The invention discloses a cloud-computing based dose verification system and method of tumor radiotherapy. The system comprises a user terminal equipment, a cloud computing server, a local therapy planning system, a computer, an HDFS data storage server and a medical linear accelerator. According to the system and method, EPID information collection is separated from dose analysis and comparison, and part which needs computing and analyzing is transferred to the server based on cloud computer; the equipment at the user end only makes therapy plans, collects, pre-processes and transmits EPID images and receives and display analysis results; and Gamma analysis between to-be-compared dose distribution and reference dose distribution is accelerated. The parallel operation mechanism of cloud computing is used, so that planning dose verification of tumor radiotherapy can be greatly accelerated, time of clinical dosimeter verification is reduced, and the efficiency of radiotherapy is improved.

A charged-particle beam exposure apparatus for exposing a member to be exposed to a charged particle beam with a pattern includes memories (902-905) for storing a plurality of control data for controlling reference dose data of the charged particle beam in accordance with the incident position of the charged particle beam on the member to be exposed, a selector (907) for selecting any one of the plurality of control data stored in the memories, and an exposure unit for controlling the reference dose data of the charged particle beam for each irradiation position on the basis of the control data selected by the selector, thereby exposing the member to be exposed with the pattern. The charged-particle beam exposure apparatus rapidly performs proper proximity effect correction to expose the member to be exposed with the pattern.

A charged particle beam writing method includes acquiring a pair of a reference dose and a backscatter coefficient for proximity effect correction using a first settling time, acquiring a first relation between a temperature rise amount and a critical dimension variation amount using a second settling time shorter than the first settling time, the backscatter coefficient and the reference dose acquired, calculating a temperature correction parameter depending on a temperature rise amount, for correcting a dose, by using the first relation, and a second relation on a dose and a pattern critical dimension in a case of using the first settling time, calculating a beam irradiation dose by the reference dose and a dose coefficient obtained from the backscatter coefficient of the pair acquired, and the temperature correction parameter, and writing a pattern with a beam based on the dose calculated using the second settling time.

The invention provides a weight adjustment method and a weight adjustment device of intensity-modulated radiation therapy. The method comprises the following steps of: a, setting a reference dose-volume histogram (DVH) curve to be an optimization target; b, solving a fluence map optimization problem to obtain a current dose-volume histogram; c, comparing the reference DVH curve with the current DVH curve to obtain a DVH evaluation index; d, judging whether to stop weight adjustment, if so, stopping weight adjustment, otherwise, executing a step e; e, adjusting a weight coefficient of an organ, thereby enabling the organ with lower DVH evaluation index to obtain higher weight coefficient, and retuning back to the step b.

A computer Chinese medicine prognosis disease inferring and prescription derivation system based on mathematics of Yin-yang and five elements comprises an existing disease symptom input module, a prognosis disease deducing-judging module, a medicament selecting module and a medicament database, wherein the medicament database stores the name, nature and taste, functions, mainly-treated symptoms, reference doses of each medicament as well as application-treatment correlation of each medicament with each visceral organ and symptom; the existing disease symptom input module provides an existing disease selection menu, so that a user can input a corresponding diseased visceral organ and the symptom by clicking the options of the existing disease selection menu according to the existing diagnostic result; the prognosis disease deducing-judging module transforms the diseased visceral organ and the symptom into existing disease semantic logic operators and conducts derivation operation thereon to obtain the un-diseased visceral organ and symptom expressed by prognosis disease semantic logic operators; and the medicament selection module obtains the diseased and un-diseased visceral organs and symptoms and selects medicaments according to the application-treatment correlation of each medicament with each visceral organ and symptom. The system realizes the standardization and automation of prognosis disease inferring and prescription derivation.

The invention discloses a public dose evaluation method based on a probability theory in radiation environment evaluation. The method comprises the following steps of analyzing and determining an irradiation path, the irradiation path comprising inhaled air internal irradiation, air immersion external irradiation, surface sediment external irradiation, internal irradiation of food-in animal and plant products and dose evaluation, and selecting a representative personal annual effective dose according to the result of the dose evaluation. According to the method, in the public dose estimation process, all the public within the illuminated range are considered, a reasonable personal annual effective dose is selected as a reference dose value, the value serves as an evaluation index in radiation environment evaluation, the conservative property of the evaluation index is further enhanced, and therefore the safety of the public and the environment is guaranteed.

A method is provided for evaluating a procedure for determining an aggregate radiotherapy dose received in the course of a radiotherapy treatment. The method includes: defining a deformable model of at least one organ to be treated and of at least one neighboring organ, generating a series of simulated images, interpretable by the procedure to be evaluated, with aid of the model; comparing the aggregate dose calculated by the procedure to be evaluated, applied to at least one of the simulated images, with a reference aggregate dose, so as to deliver at least one item of information representative of the quality of the procedure, the reference aggregate dose being obtained by taking into account anatomical deformations applied to the organs, so as to determine a reference dose actually received at each treatment session by the organs, as a function of their actual shape and / or actual position during this session.

A patterning method is provided in which a light-sensitive layer is formed, and a target resolution is defined for a pattern to be formed in a target layer. Based on a reference dose and reference LWR that results from a single patterning exposure at an EUV wavelength, the target resolution and reference dose, the light-sensitive layer is subjected to at least two radiation exposures including an EUV patterning exposure at a dose selected to be less than the reference dose and within 15 mJ / cm2-200 mJ / cm2, and a flood exposure at a wavelength of 200 nm-420 nm and a dose of 0.5 J / cm2-20 J / cm2. The light-sensitive layer is then developed to form a mask pattern, which is used to etch the pattern into the target layer with the target resolution and a LWR less than or approximately equal to the reference LWR and ≤5 nm.

In a X-ray imaging apparatus an estimation unit estimates a cumulative exposure dose of X-rays irradiated onto an object, and a remaining exposure tolerance dose calculation unit calculates a remaining exposure tolerance dose using a difference between a tolerated maximum exposure dose and the cumulative exposure dose. A X-ray irradiation tolerance period calculation unit calculates an X-ray irradiation tolerance period using a difference between a predetermined scheduled X-ray irradiation period and an actual irradiation period of X-rays irradiated onto the object, an X-ray irradiation reference dose calculation unit calculates reference dose per unit time that will form a basis for irradiation based on the remaining exposure tolerance dose and the X-ray irradiation tolerance period, and a control unit that controls X-ray irradiation of the object by setting dose per unit time within the X-ray irradiation tolerance period based on the reference dose.

The invention discloses a radiotherapy dose comparing and displaying method and system. According to the method, by obtaining reference dose values corresponding to different dose data of all kinds of coordinates, at the CT image position, of a cursor, reference isodose lines most approximate to the corresponding reference dose values among isodose lines corresponding to the different dose data of all the kinds are recognized respectively, the distance between the reference isodose line of each kind and the coordinates, at the CT image position, of the cursor is calculated, the reference isodose line with the shortest distance is used as a comparison isodose line, and other isodose lines except the isodose lines with the dose values the same as the dose value of the comparison isodose line among the isodose lines, on a CT image, of the cursor are hidden or / and the isodose lines with the dose values the same as the dose value of the comparison isodose line among the isodose lines are highlighted. Accordingly, a doctor can observe the isodose lines with the dose values the same as the dose value of the comparison isodose line among the corresponding isodose lines at the CT image position at a glance and compare the isodose lines, and the optimal radiotherapy scheme can be obtained more accurately.

The invention discloses a radiotherapy dose optimization method and device. The method comprises the following steps: acquiring a first reference dose of a target voxel set and an irradiation dose of the target voxel set; optimizing the irradiation dose of the target voxel set according to the first reference dose and a preset target function; wherein the value of the target function is in positive correlation with the difference between the irradiation dose of the target voxel set and the first reference dose; and determining that the irradiation dose of the target voxel set reaches the optimized target dose under the condition that the target function reaches a set condition. The technical problem of low radiation dose optimization efficiency caused by excessive dependence on manual debugging is solved.

The invention provides an individual dose equivalent meter calibration new method. When deep personal dose equivalent Hp(10), superficial individual dose equivalent Hp(0.07) and eye crystal dose equivalent Hp(3) individual dose equivalent meter calibration is carried out, a reference dose point (RDP) of a calibrated dosimeter is selected as Hp(d) in a die body, that is, the calibration reference point is in the die body and is at a distance of d mm from the surface in a ray vertical incident direction; and irradiation distance between a standard radiation source center (or an X-ray tube focus) and the d place of the corresponding die body calibration reference points is determined. The new method, on one hand, accords with Hp(d) individual dose equivalent definitions regulated by related international standard (ISO 4037) and national standard (GB 12162) in China, and on the other hand, improves accuracy of individual dose equivalent monitoring and scientificity of occupational hazard evaluation of massive radiation workers.

The invention provides a radiosensitive gene marker and application thereof in X-ray radiation dose monitoring. The radiosensitive gene marker comprises three up-regulation gene markers and two down-regulation gene markers; the up-regulation gene markers include Phlda3, Fgg and Kng1; the down-regulation gene markers include Ptprb and Kti. A dose-effect curve constructed based on the expression level of the radiosensitive gene marker helps determine the range of radiation dose effectively, so that the level of X-ray radiation dose can be monitored effectively to accurately prompt a reference dose of X-ray radiation based on biological effect in order to estimate nuclear radiation damage.

A simple metric, the mean absolute dose deviation (“MADD”), for characterizing dose-volume histograms (“DVH”) is disclosed. The MADD facilitates the use and the comparison of DVHs. The MADD is defined as the average of absolute differences between all points of a DVH and a dose point of a specified reference dose range. The MADD is a generalized metric free from distribution assumptions, and it is directly applicable to all types of structures.

Better Pareto dose distributions for multi-criteria optimization of treatment plans can be obtained by: - obtaining at least one reference dose function designed to result in an acceptable reference dose distribution, - defining a multi-criteria optimization problem including the at least one reference dose function as at least one optimization function, - performing at least two optimization procedures based on the multi-criteria optimization problem to generate a set of at least two possible treatment plans, - obtaining a treatment plan to be used for treating the patient, based on the set of possible treatment plans, by selecting one plan or by combining plans.

In a method, a water equivalent diameter (abbreviated to WED) of a slice plane of an examination volume is received via an interface. In an embodiment, a noise level based on the water equivalent diameter is determined via a computer unit, the noise level being an upper threshold value for the noise of a CT image dataset. Furthermore a reference dose parameter is determined based on the noise level and the water equivalent diameter via the computer unit, the reference dose parameter corresponding to a first x-ray dose, which would be absorbed in the slice plane during a recording of a first CTimage dataset of the examination volume upon the noise of the first CT image dataset corresponding to the noise level. Finally, the reference dose parameter is indirectly proportional to a power of the noise level.

A simple metric, the mean absolute dose deviation (“MADD”), for characterizing dose-volume histograms (“DVH”) is disclosed. The MADD facilitates the use and the comparison of DVHs. The MADD is defined as the average of absolute differences between all points of a DVH and a dose point of a specified reference dose range. The MADD is a generalized metric free from distribution assumptions, and it is directly applicable to all types of structures.