CN110170109A - The orthogonal double-deck grating device and its Ziye for radiotherapy apparatus divide control method - Google Patents
The orthogonal double-deck grating device and its Ziye for radiotherapy apparatus divide control method Download PDFInfo
- Publication number
- CN110170109A CN110170109A CN201811577792.3A CN201811577792A CN110170109A CN 110170109 A CN110170109 A CN 110170109A CN 201811577792 A CN201811577792 A CN 201811577792A CN 110170109 A CN110170109 A CN 110170109A
- Authority
- CN
- China
- Prior art keywords
- blade
- matrix
- grating
- segmentation
- intensity
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N5/00—Radiation therapy
- A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
- A61N5/103—Treatment planning systems
- A61N5/1031—Treatment planning systems using a specific method of dose optimization
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N5/00—Radiation therapy
- A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
- A61N5/1042—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy with spatial modulation of the radiation beam within the treatment head
- A61N5/1043—Scanning the radiation beam, e.g. spot scanning or raster scanning
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N5/00—Radiation therapy
- A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
- A61N5/1042—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy with spatial modulation of the radiation beam within the treatment head
- A61N5/1045—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy with spatial modulation of the radiation beam within the treatment head using a multi-leaf collimator, e.g. for intensity modulated radiation therapy or IMRT
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N5/00—Radiation therapy
- A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
- A61N5/1048—Monitoring, verifying, controlling systems and methods
- A61N5/1049—Monitoring, verifying, controlling systems and methods for verifying the position of the patient with respect to the radiation beam
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N5/00—Radiation therapy
- A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
- A61N5/1048—Monitoring, verifying, controlling systems and methods
- A61N5/1071—Monitoring, verifying, controlling systems and methods for verifying the dose delivered by the treatment plan
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N5/00—Radiation therapy
- A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
- A61N5/1048—Monitoring, verifying, controlling systems and methods
- A61N5/1049—Monitoring, verifying, controlling systems and methods for verifying the position of the patient with respect to the radiation beam
- A61N2005/1054—Monitoring, verifying, controlling systems and methods for verifying the position of the patient with respect to the radiation beam using a portal imaging system
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61N—ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY
- A61N5/00—Radiation therapy
- A61N5/10—X-ray therapy; Gamma-ray therapy; Particle-irradiation therapy
- A61N2005/1092—Details
- A61N2005/1094—Shielding, protecting against radiation
Abstract
The present invention provides a kind of orthogonal double-deck grating devices and its Ziye for radiotherapy apparatus to divide control method.The wherein orthogonal double-deck grating device, it is installed under the accelerator head of radiotherapy apparatus, it include: upper layer grating blade and lower layer's grating blade, plane where the upper layer grating blade and lower layer's grating blade is parallel to each other, and perpendicular to the directions of rays that the accelerator head issues, the direction of motion of the upper layer grating blade and lower layer's grating blade is orthogonal；Ziye divides control method and is based on above-mentioned friendship double-layer grating device.Divide control method provided by the present invention for the orthogonal double-deck grating device and its Ziye of radiotherapy apparatus, conformal degree and therapeutic efficiency can be obviously improved, have extremely important meaning for clinic.
Description
Technical field
The present invention relates to radiotherapy equipment fields, and in particular to a kind of orthogonal double-deck grating device for radiotherapy apparatus
And its Ziye divides control method.
Background technique
A kind of local treatment means of the radiotherapy as tumour, always in a basic problem for constantly seeking to solve
It is how preferably to handle the dose relationship of tumor tissues (target area) and normal surrounding tissue, obtain tumour to greatest extent
Partial controll and the radiation insult of normal surrounding tissue and organ is minimum.
Grating is that a kind of essential leafy collimating apparatus of modern radiotherapy apparatus can by the movement of grating blade
To have extraordinary conformal effect to target area, under normal circumstances, the blade of multi-diaphragm collimator is thinner, and quantity is more, leafy standard
The conformal degree of straight device is better, but for conventional single layer grating, since blade can only move in one direction, blade is thick
The conformability for spending direction is limited, for parallel double-layer grating, although its vane thickness direction is suitable compared to single layer grating
Shape ability increases, but is limited to the influence of vane thickness, can not move or be formed the irradiation list of any position
Member；Such as application No. is 201520205602.0 Chinese patents, disclose a kind of grating device for radiotherapy equipment,
End-position controller is set simultaneously and front position controller can verify simultaneously single grating blade end-position and in
Between position, and measure at any time a certain grating blade from end-position reach middle position time and/or motor total revolution,
Since the distance between end-position and middle position are determining constant, and can accurately measure, therefore, precise verification and
It controls a certain grating blade and reaches a certain accurately specified position, the verification one by one due to the realization that can be convenient to grating blade
And control, therefore different grating blade drive system bring driving errors and the unstable bring of performance can effectively be overcome to miss
Difference, by realizing precisely walking for each grating blade, to reach preferable conformal effect, but it does not change it
Grating carries out the conformal essential concept blocked, and illumination efficiency is still low, and there are grating leakages to penetrate, and can not preferably protect danger
And organ, there is an urgent need to be improved.
Static intensity modulating Ziye divides (step-shoot) method, it is important to which the segmentation of Ziye sequence is intended to require strong
Degree is layered, and the movement of single layer grating is then controlled, and each launched field is divided into a series of Ziyes and carries out once irradiating, until
All Ziye irradiations finish the required intensity distribution that realizes a plan comprising following steps:
Firstly, being drawn according to the dose constraint or biological constraints of organ and target area according to optimization by treatment planning systems (TPS)
It holds up, the intensity matrix after calculating each launched field optimization is denoted as P[p×q], wherein p, q are the hits of matrix；
Then, in order to carry out Ziye segmentation, here the matrix after optimization in vane thickness direction resampling.If grating
It is horizontally mounted, then the matrix after resampling is denoted as D[M×N], M is set as the number of intensity map intra vane, and N is set as 256, and matrix is hanging down
Histogram to sampling interval be vane thickness, the sampling interval in the horizontal direction is set as 0.25；Resampling matrix compares original matrix
It is big in the sampling interval of vertical direction, it is meant that this procedural strength matrix has loss, and in a practical situation, i.e., blade is at it for performance
The conformability of thickness direction is poor.
By the intensity distribution in previous step, it is divided into step-like strength grade, strength grade at equal intervals according to intensity
Size determines the precision of segmentation and the complexity of Ziye；Under normal conditions, 10 grades are divided, the matrix after division is denoted as A[M×N]；
Finally, starting Ziye segmentation, intensity matrix A[M×N]It can be analyzed to multiple Ziyes:
Wherein, ukFor MU value, SkFor Ziye matrix；Total MU value and total Ziye number determine illumination efficiency, and total MU value is lower,
Total Ziye number is fewer, and irradiation time is shorter, and efficiency is higher.At this point, selecting the one third of current maximum intensity strong as segmentation
Angle value is selected the matrix (Ziye matrix) of this segmentation under conditions of dividing intensity value, is subtracted from current intensity matrix point
Cutting torch battle array:
A=A-uksk (2)
Selection segmentation intensity value is repeated, subdivision matrix is selected, until A[M×N]It is reduced to 0.
When Ziye matrix selects, it is noted that Ziye SkIt is to be made of multipair blade (MLC) opening, defines intensity map here
For interior shared m to blade, the position of the lobus sinister piece and lobus dexter piece (by taking the single layer grating that 0 ° is installed as an example) of each pair of blade is respectively l,
R, then spacing with blades I are as follows:
I={ x ∈ [n]: l≤x≤r } (3)
Ziye may be expressed as:
For each pair of blade, maximum one section of spacing with blades is taken as opening, i.e. spacing with blades I length is maximum.As (1,
1,1,0,1,0), single layer grating will take (1,1,1,0,0,0) as its opening shape for the first time, divide in two times.
In the case where blade can not overlap, there is also constraint, the referred to as not overlapping constraints of blade between blade pair
(interleaf collision constraint-ICC), i.e. there are crossover region α by Fig. 1, therefore two kinds of situations can not be sent out in Fig. 1
Raw, for single layer grating (parallel single layer grating), to meet the not overlapping constraint of blade, above situation can only be divided in two times
It completes.Therefore, multisection type intensity distribution and blade can not overlap constraint and all limit the illumination efficiency of single layer grating.
Specifically, (its by taking the segmentation of the Ziye of 5 × 8 matrixes containing more connected regions of following sphere of movements for the elephants shape intensity maps as an example
In middle matrix 1 or 2 for target area and its dose intensity, then representing normal tissue with 0), in order to reach multisection type intensity point
Butut and blade can not overlap constraint condition, and intensity matrix is divided into following four segmentations by the single layer grating segmentation of 0 ° of installation:
According to above-mentioned dividing method, the single layer grating of 0 ° of installation to the segmentation result of sphere of movements for the elephants shape intensity map as shown in fig. 6,
Grating leaf position in Fig. 6 correspond respectively to above-mentioned matrix four times segmentation, be corresponding in turn in；The similarly single layer light of 90 ° of installations
Grid are as shown in Figure 7 to the segmentation result of sphere of movements for the elephants shape intensity map.
Optimize intensity matrix (P according to the acquisition after the optimization of above-mentioned launched field[p×q]) method and above-mentioned Ziye segmentation side
Method, the segmentation result such as Fig. 9 of 0 ° of single layer grating installed to triangle disposition intensity map；The similarly single layer grating pair of 90 ° of installations
The segmentation result of triangle disposition intensity map is as shown in Figure 10, is not repeating herein.
To sum up, either single layer grating or parallel double-layer grating, can all face following problem；
1, the conformal degree in vane thickness direction is inadequate；
2, it can not overlap constraint in order to meet multisection type intensity distribution and blade and all limit the irradiation effect of single layer grating
Rate, a complicated launched field, needs multiple Ziyes that can be formed, illumination efficiency is low.
Summary of the invention
To solve the above problems, the present invention provides a kind of orthogonal double-deck grating devices and its Ziye for radiotherapy apparatus
Divide control method.Divide control method provided by the present invention for the orthogonal double-deck grating device and its Ziye of radiotherapy apparatus,
It can be obviously improved conformal degree and therapeutic efficiency, have extremely important meaning for clinic.
The technical purpose is realized, the technical scheme is that a kind of orthogonal double-layer grating for radiotherapy apparatus fills
It sets, is installed under the accelerator head of radiotherapy apparatus, comprising:
Plane where upper layer grating blade and lower layer's grating blade, the upper layer grating blade and lower layer's grating blade is mutual
In parallel, and perpendicular to the directions of rays that the accelerator head issues, the fortune of the upper layer grating blade and lower layer's grating blade
Dynamic direction is orthogonal；
The upper layer grating blade includes left side blade and the right blade, for moving to search at left and right sides of target area；
Lower layer's grating blade includes top blade and following blade, for mobile to two-sided search above and below target area；
Controller, for driving every blades list in left side blade and the right blade, top blade and following blade
Solely movement, it is conformal with target area to achieve the purpose that.
A kind of Ziye segmentation control method (step-shoot), has used the above-mentioned orthogonal double-layer grating for radiotherapy apparatus
Device, comprising the following steps:
S1: the optimization matrix that dose intensity is determined by treatment planning systems (TPS) is determined；
S2: by the optimization matrix resampling in the step S1, the dimension of adjusting and optimizing matrix；
S3: by the matrix after resampling in the step S2, it is divided into stairstepping strength grade at equal intervals according to intensity；
S4: it according to the maximum intensity in the step S3, determines segmentation intensity value, divides solve this under intensity value herein
The matrix of secondary segmentation；
S5: calculating the maximum rectangular extent of this subdivision matrix profile, and according to maximum rectangular extent, it is suitable to calculate needs
The intensity matrix range of the grating blade of shape, left side blade and the right blade, top blade and following blade move conformal to this
Intensity matrix volume edges.
As a kind of preferred embodiment of the invention, it is based on above content, the optimization matrix note in the step S1
For P[p×q], P is adjusted in the step S2[p×q]The value of middle p, q, and it is denoted as D[M×N], M is set as 256, N and is set as 256, and matrix is hanging down
Histogram is set as 0.25 to the sampling interval with horizontal direction；
The stairstepping strength grade divided at equal intervals in the step S3 according to intensity is 10 grades, is divided in the step S4
Intensity value is the one third of current maximum intensity.
Further, in the step S5, left side blade and the right blade, top blade and following blade it is mobile it is conformal extremely
Method are as follows: to left side blade, search for from left to right, until hitting target area, corresponding the right blade is turned left search from the right side, until
Hit target area；If left side blade cannot hit target area, this group of blade is closed in edge；To top blade, search from top to bottom
Rope, until hitting target area, corresponding following blade is searched for from the bottom up, until hitting target area；If top blade cannot hit target
Area, then this group of blade is closed in edge.
Further, further include the steps that blocking leakage exit point:
S6: it in the step S5 after top blade, following blade, left side blade, the conformal movement of the right blade, calculates real
The optimization matrix of the dose intensity determined in border subdivision matrix, practical subdivision matrix and the step S1, i.e. expected matrix；
If practical subdivision matrix is greater than desired subdivision matrix, leaf position is adjusted, practical subdivision matrix is blocked and is greater than expectation segmentation square
Pixel at battle array position, i.e. leakage exit point, allow it to be less than or equal to desired subdivision matrix.
Further, blocked in the step S6 leakage exit point method the following steps are included:
T1: finding the pixel that practical subdivision matrix is greater than desired subdivision matrix, creates the matrix of a storage abnormal point；
T2: all the points of matrix abnormal in step T1 are progressively scanned, calculate current abnormal point apart from upper and lower, left and right four
A direction corresponds to the effective distance of blade, which is expressed as, and blade blocks the normal point for needing to cover to current abnormal point
Points, top blade, following blade, left side blade, the right blade four direction blade correspond to effective distance it is the smallest just choosing
To block blade, current vane position is updated；
T3: after all the points end of scan of abnormal matrix, with the current vane position and desired subdivision matrix in step T2
Comparison, update abnormal matrix judge whether that there are also abnormal points, if so, then repeating step T1-T2.
Further, in the step T1, the method for finding abnormal point are as follows: to the grating being horizontally mounted, if matrix is a certain
The center of pixel is fallen between the lower edges of some blade of grating, it is considered that the pixel is subordinated to this leaf
Piece；To vertically arranged grating, if the center of a certain pixel of matrix falls within the left and right edges of some blade of grating
Between, it is considered that the pixel is subordinated to this blade；If state (open or close) and expected matrix of this blade at pixel
State (0 or 1) be consistent, then it is assumed that this pixel is normal, on the contrary then think abnormal.
As a kind of preferred embodiment of the invention, it is based on above content, unlike, it further include Optimized Segmentation
The step of:
S7: from practical subdivision matrix adjusted in the step S6 is subtracted in total subdivision matrix, new segmentation square is obtained
Battle array repeats step S4-S5, until new subdivision matrix is 0；
S8: to all Ziyes of above-mentioned steps, its weight is optimized using least square method, guarantees final segmentation
As a result minimum with expected matrix in step 1, complete segmentation.
As another preferred embodiment of the invention, it is based on above content, unlike, it further include further including
The step of intensity value is divided in adjustment, reduces total MU:
S7: calculating the area of practical subdivision matrix in the step S6, and the product with this area and segmentation intensity value is to comment
Price card is quasi-；If the product value after current segmentation is greater than the product value of last segmentation, then by point in the step S4
It cuts intensity value and subtracts one, solve the matrix of this segmentation, repeat step S5-S6；Conversely, then carrying out step S8；
S8: from practical subdivision matrix in the step S6 is subtracted in total subdivision matrix, obtaining new subdivision matrix, repeats to walk
Rapid S4-S7, until new subdivision matrix is 0；
S9: to all Ziyes of above-mentioned steps, its weight is optimized using least square method, guarantees final segmentation
As a result minimum with expected matrix in step 1, complete segmentation.
The beneficial effects of the present invention are:
1) it is conformal to target location (intensity matrix edge) that the invention firstly uses orthogonal double-layer grating surrounding blade synchronizations,
Then detect inside the one or more regions surrounded whether there is or not leakage exit point.Which overcome conventional monolayers tube shutters in order to meet multistage
The shortcomings that formula intensity distribution and blade can not overlap constraint and limit illumination efficiency.
2) orthogonal double-layer grating of the invention takes advantage on conformal degree, and double-layer grating can effectively reduce grating leakage and penetrate,
It can preferably protect and jeopardize organ.
3) Ziye based on the orthogonal double-deck grating device of the present invention altogether divides control method, solve one it is complicated
Launched field needs multiple Ziyes that can be formed, the low problem of illumination efficiency.
To sum up, divide control method provided by the present invention for the orthogonal double-deck grating device and its Ziye of radiotherapy apparatus,
It can be obviously improved conformal degree and therapeutic efficiency, have extremely important meaning for clinic.
Detailed description of the invention
Fig. 1 is that the blade of single layer grating Ziye segmentation overlaps schematic diagram；
Fig. 2 is that orthogonal double-layer grating solves the overlapping schematic diagram of blade；
Fig. 3 is the overall flow figure of the orthogonal double-layer grating Ziye segmentation of the present invention；
Fig. 4 is that the orthogonal double-layer grating blade of the present invention blocks flow chart；
Fig. 5 is the method flow diagram that the orthogonal double-layer grating of the present invention reduces total MU；
Fig. 6 is segmentation result of the single layer grating to sphere of movements for the elephants shape intensity map of 0 ° of installation；
Fig. 7 is segmentation result of the single layer grating to sphere of movements for the elephants shape intensity map of 90 ° of installations；
Fig. 8 is segmentation result of the orthogonal double-layer grating of the present invention to sphere of movements for the elephants shape intensity map；
Fig. 9 is segmentation result of the single layer grating to triangle disposition intensity map of 0 ° of installation；
Figure 10 is segmentation result of the single layer grating to triangle disposition intensity map of 90 ° of installations；
Figure 11 is segmentation result of the orthogonal double-layer grating of the present invention to triangle disposition intensity map；
Figure 12 is the DVH figure of prostate 1 (band * is orthogonal double-layer grating result)；
Figure 13 is the DVH figure of the more target areas of brain metastes (band * is orthogonal double-layer grating result)；
Figure 14 is the DVH figure of prostate 2 (band * is orthogonal double-layer grating result)；
Figure 15 is the DVH figure of the carcinoma of the rectum (band * is orthogonal double-layer grating result)；
Figure 16 is the DVH figure of liver cancer (band * is orthogonal double-layer grating result)；
Figure 17 is the DVH figure of the lower end cancer of the esophagus (band * is orthogonal double-layer grating result)；
Figure 18 is the DVH figure of cancer of pancreas (band * is orthogonal double-layer grating result)；
Figure 19 is the DVH figure of cervical carcinoma (band * is orthogonal double-layer grating result)；
Figure 20 is the DVH figure of gastric cancer (band * is orthogonal double-layer grating result)；
Figure 21 is the DVH figure of peripheral type carcinoma of lung (band * is orthogonal double-layer grating result)；
Figure 22 is the DVH figure of Coeliac lymphadenectomy (band * is orthogonal double-layer grating result)；
Figure 23 is the DVH figure of breast cancer (band * is orthogonal double-layer grating result)；
Figure 24 is the Ziye segmentation statistics pair of double-layer grating and 12 cases of the single layer grating in Figure 12-Figure 23 of the invention
According to chart；
Figure 25 is the segmentation statistics parallel tables of double-layer grating and single layer grating before improved double-layer grating, improvement.
Specific embodiment
Technical solution of the present invention will be clearly and completely described below.
A kind of orthogonal double-deck grating device for radiotherapy apparatus, is installed under the accelerator head of radiotherapy apparatus, such as Fig. 2
It is shown, comprising:
Plane where upper layer grating blade and lower layer's grating blade, the upper layer grating blade and lower layer's grating blade is mutual
In parallel, and perpendicular to the directions of rays that the accelerator head issues, the fortune of the upper layer grating blade and lower layer's grating blade
Dynamic direction is orthogonal；It should be noted that the upper and lower are for the vertical height of the orthogonal double-deck grating device.
The upper layer grating blade includes left side blade and the right blade, for moving to search at left and right sides of target area；
Lower layer's grating blade includes top blade and following blade, for mobile to two-sided search above and below target area；It needs
It is noted that top blade and following blade are for the front-rear position of lower layer's grating blade or target area plane.
Above-mentioned orientation is used to be for illustrating the position of grating blade of the present invention and the relationship that walks, and can not be interpreted as to the present invention
Restriction.
Controller, for driving every blades list in left side blade and the right blade, top blade and following blade
Solely movement, it is conformal with target area to achieve the purpose that.Using above-mentioned dual-layer Parallel and the grating blade that walks orthogonal, target area can be made
Conformal degree is higher, and both direction can be less than the precision that walks of 1mm.
A kind of Ziye segmentation control method has used the above-mentioned orthogonal double-deck grating device for radiotherapy apparatus, such as Fig. 3 institute
Show, comprising the following steps:
S1: the optimization matrix that dose intensity is determined by treatment planning systems (TPS) is determined；Optimizing matrix is by TPS system
According to target area and jeopardize the dose constraint of organ and other constrained optimizations calculate and go out, optimization matrix determine final target area with
Jeopardize organ dose distribution, Ziye segmentation after actual matrix closer to optimization matrix, actual dose distribution also closer to
Dosage distribution after optimization, resulting treatment plan quality are higher；
S2: by the optimization matrix resampling in the step S1, the dimension of adjusting and optimizing matrix；Conventional monolayers grating exists
When resampling, the sampling interval of the blade direction of motion is related to the precision that walks of practical blade, typically small；Vane thickness direction
Sampling interval then directly by vane thickness divide, this process is down-sampled process, and intensity matrix has loss.Orthogonal bilayer
Grating is in resampling, it is contemplated that both direction blade has movement, therefore intensity matrix is between the sampling of two orthogonal directions
It is related to the precision that walks of practical blade every being consistent, it is generally smaller than vane thickness.Orthogonal grating intensity matrix resampling
When, the loss for comparing original matrix is smaller.
S3: by the matrix after resampling in the step S2, it is divided into stairstepping strength grade at equal intervals according to intensity；
Strength grade size determines the precision of segmentation and the complexity of Ziye.Strength grade is higher, matrix and original matrix after segmentation
Error with regard to smaller, but simultaneously, Ziye number increases, irradiation time is elongated.
S4: it according to the maximum intensity in the step S3, determines segmentation intensity value, divides solve this under intensity value herein
The matrix of secondary segmentation；
S5: calculating the maximum rectangular extent of this subdivision matrix profile, and according to maximum rectangular extent, it is suitable to calculate needs
The intensity matrix range of the grating blade of shape, left side blade and the right blade, top blade and following blade move conformal to this
Intensity matrix volume edges.
As a kind of preferred embodiment of the invention, it is based on above content, the optimization matrix note in the step S1
For P[p×q], P is adjusted in the step S2[p×q]The value of middle p, q, and it is denoted as D[M×N], M is set as 256, N and is set as 256, and matrix is hanging down
Histogram is set as 0.25 to the sampling interval with horizontal direction；
The stairstepping strength grade divided at equal intervals in the step S3 according to intensity is 10 grades, is divided in the step S4
Intensity value is the one third of current maximum intensity.It is practical to be suitable for this orthogonal double-layer grating using above-mentioned technical parameter.
Further, in the step S5, left side blade and the right blade, top blade and following blade it is mobile it is conformal extremely
Method are as follows: to left side blade, search for from left to right, until hitting target area, corresponding the right blade is turned left search from the right side, until
Hit target area；If left side blade cannot hit target area, this group of blade is closed in edge；To top blade, search from top to bottom
Rope, until hitting target area, corresponding following blade is searched for from the bottom up, until hitting target area；If top blade cannot hit target
Area, then this group of blade is closed in edge.
Further, further include the steps that blocking leakage exit point:
S6: it in the step S5 after top blade, following blade, left side blade, the conformal movement of the right blade, calculates real
The optimization matrix of the dose intensity determined in border subdivision matrix, practical subdivision matrix and the step S1, i.e. expected matrix；
If practical subdivision matrix is greater than desired subdivision matrix, leaf position is adjusted, practical subdivision matrix is blocked and is greater than expectation segmentation square
Pixel at battle array position, i.e. leakage exit point, allow it to be less than or equal to desired subdivision matrix.
Further, as shown in figure 4, blocked in the step S6 leakage exit point method the following steps are included:
T1: the pixel that practical subdivision matrix is greater than desired subdivision matrix, i.e. leakage exit point or abnormal point are found, creates one
Store the matrix of abnormal point；
T2: all the points of matrix abnormal in step T1 are progressively scanned, calculate current abnormal point apart from upper and lower, left and right four
A direction corresponds to the effective distance of blade, which is expressed as, and blade blocks the normal point for needing to cover to current abnormal point
Points, top blade, following blade, left side blade, the right blade four direction blade correspond to effective distance it is the smallest just choosing
To block blade, current vane position is updated；
T3: after all the points end of scan of abnormal matrix, with the current vane position and desired subdivision matrix in step T2
Comparison, update abnormal matrix judge whether that there are also abnormal points, if so, then repeating step T1-T2.
Further, in the step T1, the method for finding abnormal point are as follows: to the grating being horizontally mounted, if matrix is a certain
The center of pixel is fallen between the lower edges of some blade of grating, it is considered that the pixel is subordinated to this leaf
Piece；To vertically arranged grating, if the center of a certain pixel of matrix falls within the left and right edges of some blade of grating
Between, it is considered that the pixel is subordinated to this blade；If state (open or close) and expected matrix of this blade at pixel
State (0 or 1) be consistent, then it is assumed that this pixel is normal, on the contrary then think abnormal.
As a kind of preferred embodiment of the invention, it is based on above content, unlike, as shown in figure 3, also wrapping
It includes, (claims double-layer grating before improving) the step of Optimized Segmentation:
S7: from practical subdivision matrix adjusted in the step S6 is subtracted in total subdivision matrix, new segmentation square is obtained
Battle array repeats step S4-S5, until new subdivision matrix is 0；
S8: to all Ziyes of above-mentioned steps, its weight is optimized using least square method, guarantees final segmentation
As a result minimum with expected matrix in step 1, complete segmentation.
Divide control method based on the above-mentioned orthogonal double-deck grating device and its Ziye for radiotherapy apparatus, with following " fields "
For the Ziye segmentation of 5 × 8 matrixes (C) containing more connected regions of font intensity map, intensity matrix is divided in two times: first
The secondary one third for taking maximum intensity value is segmentation intensity value, and this example 1, with 1 for intensity partition value, surrounding blade is closed to by force
Figure edge is spent, checks internal whether there is or not abnormal point, point without exception in this example, therefore does not need to execute blade and blocks program, completes one
Secondary segmentation obtains residual intensity matrix；It takes residual intensity matrix to do same dividing processing for the second time, completes second and divide,
It is second of residual matrix that residual intensity matrix, which subtracts second of subdivision matrix, matrix is divided into C1+C2, in matrix at this time
Portion's value is all 0, and segmentation is completed.Segmentation result is as follows:
In this case, parallel single layer grating needs to divide in two times, but as it appears from the above, orthogonal double-layer grating can be primary
Segmentation is completed.The intensity matrix of multiple isolated areas is especially included, orthogonal double-layer grating often can once divide completion, pendulum
The not overlapping constraint (interleaf collision constraint-ICC) of single layer grating has been taken off, thus has been greatly improved
Illumination efficiency.
Program operation result of this example on TPS is as shown in Figure 8, it is seen that in this example, compares single layer grating, orthogonal bilayer
The Ziye of grating divides total MU and Ziye number all decreases.Continue by taking triangle disposition intensity matrix as an example, single layer grating and double
Layer grating comparison diagram such as Fig. 9-Figure 11, it is seen then that for it is some comprising the intensity map of more connected regions for, orthogonal double-layer grating
Segmentation Ziye number is few, and total MU is low, and illumination efficiency is high.Meanwhile single layer grating is because there is impeller clearance to limit the (left and right of a pair of of blade
Minimum clearance between blade), therefore each pair of blade outside intensity matrix can have a narrow slit, and the leakage of ray is caused to penetrate.
And two layers of grating of double-layer grating can play a complementary effect, vertically arranged grating can hide the narrow slit of horizontal grating
Gear, horizontal grating can also block the narrow slit of vertically arranged grating, cause the leakage of double-layer grating to be penetrated less.In addition, comparing list
Layer grating, ray also decrease by the transmissivity of double-layer grating.To sum up, double-layer grating can reduce the transmission of ray, leakage
It penetrates, preferably protection jeopardizes organ.
Then, we illustrate the algorithm that blade blocks in shown step S6 by taking 4 × 4 intensity matrix as an example.Here
It is first considered that consistent with the intensity matrix sampling interval (i.e. a pair of of blade can for the grating being horizontally mounted and vertically arranged installation thickness
Block a row or column data).So for following initial optimization matrix A, surrounding blade is conformal at matrix edge first,
The practical subdivision matrix formed is A1, it is seen that practical subdivision matrix is bigger than initial optimization matrix, and internal there are an abnormal points
“0”。
To implement blade below and blocks algorithm, " 0 " present position is subordinated to second pair of horizontal blade (remembering from top to bottom), and second
It (turns left note from the right side) to vertical vane, lobus sinister piece needs to block 2 virtual values, effective distance is 2, similarly to block " 0 "
Lobus dexter piece effective distance is 1, and blade effective distance is 1, and lower blade effective distance is 2, therefore, can choose blade or lobus dexter
Piece is used as and blocks blade.If selecting blade to block blade, then the practical subdivision matrix formed is A2, once segment
At second of segmentation can be continued to execute.Ultimately form segmentation result as shown in Figure 8.And the above method is utilized, orthogonal bilayer light
Grid are finally as shown in figure 11 to the segmentation result of triangle disposition intensity map, and this will not be repeated here.
The premise of an example is that the thickness of horizontal and vertical blade is consistent with matrix sampling interval above, it is assumed here that different
It causes, horizontal blade thickness is twice of matrix sampling interval, and vertical vane thickness is still equal to the sampling interval, then surrounding blade
It is conformal to matrix edge, the practical subdivision matrix of formation is B1, it is seen that there is leakage exit point at two.It is tertial that the second row is analyzed first
Exit point is leaked, it is subordinated to first pair of horizontal blade and second pair of vertical vane, and to block the point, lobus sinister piece, which will block 5, to be had
Point, effective distance 5 are imitated, lobus dexter piece effective distance is 2, and blade effective distance is 1, and lower blade effective distance is 2, therefore is selected
Blade is blocked.Then the leakage exit point of the third line secondary series is analyzed, it is subordinated to second pair of horizontal blade, and third is to vertical
Blade, lobus sinister piece effective distance are 1, and lobus dexter piece is 3, blade 2, and lower blade is 1, and selecting lower blade is to block blade.Finally
The subdivision matrix of formation is B2, this segmentation completion, continuation segmentation next time.
As another preferred embodiment of the invention, it is based on above content, unlike, as shown in figure 5, also wrapping
The step of including, adjustment segmentation intensity value, reducing total MU (improved double-layer grating):
S7: calculating the area of practical subdivision matrix in the step S6, and the product with this area and segmentation intensity value is to comment
Price card standard (referred to as income)；If the product value that the product value (income) after current segmentation is greater than last segmentation (is received
Benefit), then subtracting one for the segmentation intensity value in the step S4, the matrix of this segmentation is solved, repeats step S5-S6, into
Row is divided again；Conversely, then carrying out step S8；
S8: from practical subdivision matrix in the step S6 is subtracted in total subdivision matrix, obtaining new subdivision matrix, repeats to walk
Rapid S4-S7, until new subdivision matrix is 0；
S9: to all Ziyes of above-mentioned steps, its weight is optimized using least square method, guarantees final segmentation
As a result minimum with expected matrix in step 1, complete segmentation.
Using in the present embodiment adjustment segmentation intensity value, the method for reducing total MU, with divide after Ziye area and
The product for dividing intensity value is evaluation criterion, adjusts the segmentation intensity value divided every time.It overcomes and divides the later period in Ziye, because strong
It spends internal matrix point to be distributed irregular (there are a large amount of concave polygons), double-layer grating blade has blocked mass efficient point, segmentation time
Number increases, total higher disadvantage of MU value.
Divide control method based on the above-mentioned orthogonal double-deck grating device and its Ziye for radiotherapy apparatus, is applied to as schemed
In actual case shown in 12-23,12 different cases are selected to be tested here, their Ziye number and MU statistical result is such as
Figure 24 and Figure 25, it is seen that having total MU value of 8 cases in 12 cases has different degrees of reduction, as the more target areas of brain metastes
More target area cases are the most significant, and Ziye number increases except an example case, and an example case is fair outer, remaining case has different degrees of
Decline.Dose volume histogram-DVH the figure (Figure 12-Figure 23) of 12 cases is compared it is found that orthogonal double-layer grating can be preferably
Protection jeopardizes organ (band * is double-layer grating, and DVH curve location is on the lower).To sum up, orthogonal double-layer grating can not only reduce always
MU, total Ziye number improve illumination efficiency, can also preferably protect and jeopardize organ.
For those of ordinary skill in the art, without departing from the concept of the premise of the invention, it can also do
Several modifications and improvements out, these are all within the scope of protection of the present invention.
Claims (9)
1. a kind of orthogonal double-deck grating device for radiotherapy apparatus, is installed under the accelerator head of radiotherapy apparatus, feature
It is, comprising:
Upper layer grating blade and lower layer's grating blade, the upper layer grating blade and plane where lower layer's grating blade are mutually equal
Row, and perpendicular to the directions of rays that the accelerator head issues, the movement of the upper layer grating blade and lower layer's grating blade
Direction is orthogonal；
The upper layer grating blade includes left side blade and the right blade, for moving to search at left and right sides of target area；
Lower layer's grating blade includes top blade and following blade, for mobile to two-sided search above and below target area；
Controller, for driving every blades in left side blade and the right blade, top blade and following blade individually to transport
It is dynamic, it is conformal with target area to achieve the purpose that.
2. a kind of Ziye divides control method, the orthogonal double-layer grating as described in claim 1 for being used for radiotherapy apparatus has been used
Device, which comprises the following steps:
S1: the optimization matrix that dose intensity is determined by treatment planning systems (TPS) is determined；
S2: by the optimization matrix resampling in the step S1, the dimension of adjusting and optimizing matrix；
S3: by the matrix after resampling in the step S2, it is divided into stairstepping strength grade at equal intervals according to intensity；
S4: it according to the maximum intensity in the step S3, determines segmentation intensity value, divides solve this point under intensity value herein
The matrix cut；
S5: calculating the maximum rectangular extent of this subdivision matrix profile, and according to maximum rectangular extent, it is conformal to calculate needs
The intensity matrix range of grating blade, left side blade and the right blade, top blade and the movement of following blade are conformal to the intensity
Matrix volume edges.
3. Ziye according to claim 2 divides control method, which is characterized in that
Optimization matrix in the step S1 is denoted as P[p×q], P is adjusted in the step S2[p×q]The value of middle p, q, and be denoted as
D[M×N], M is set as 256, N and is set as 256, and the sampling interval of matrix in the vertical direction and the horizontal direction is set as 0.25；
The stairstepping strength grade divided at equal intervals in the step S3 according to intensity is 10 grades, divides intensity in the step S4
Value is the one third of current maximum intensity.
4. Ziye according to claim 3 divides control method, which is characterized in that in the step S5, left side blade and
The mobile conformal method extremely of the right blade, top blade and following blade are as follows: to left side blade, search for from left to right, Zhi Daoming
Middle target area, corresponding the right blade are turned left search from the right side, until hitting target area；If left side blade cannot hit target area, the group
Blade is closed in edge；To top blade, search for from top to bottom, until hit target area, corresponding following blade, from the bottom up
Search, until hitting target area；If top blade cannot hit target area, this group of blade is closed in edge.
5. Ziye according to claim 4 divides control method, which is characterized in that further include the steps that blocking leakage exit point:
S6: in the step S5 after top blade, following blade, left side blade, the conformal movement of the right blade, practical point is calculated
The optimization matrix of the dose intensity determined in cutting torch battle array, practical subdivision matrix and the step S1, i.e. expected matrix；If real
Border subdivision matrix is greater than desired subdivision matrix, then adjusts leaf position, blocks practical subdivision matrix greater than desired subdivision matrix position
The pixel at place is set, i.e. leakage exit point, it is allowed to be less than or equal to desired subdivision matrix.
6. Ziye according to claim 5 divides control method, which is characterized in that block leakage exit point in the step S6
Method the following steps are included:
T1: finding the pixel that practical subdivision matrix is greater than desired subdivision matrix, creates the matrix of a storage abnormal point；
T2: all the points of matrix abnormal in step T1 are progressively scanned, calculate current abnormal point apart from four, upper and lower, left and right side
To the effective distance of corresponding blade, which is expressed as, and blade blocks the point for the normal point for needing to cover to current abnormal point
Number, top blade, following blade, left side blade, the right blade four direction blade correspond to that effective distance is the smallest to be just selected as
Blade is blocked, current vane position is updated；
T3: after all the points end of scan of abnormal matrix, being compared with the current vane position in step T2 with desired subdivision matrix,
Update abnormal matrix judges whether that there are also abnormal points, if so, then repeating step T1-T2.
7. Ziye according to claim 6 divides control method, which is characterized in that in the step T1, find abnormal point
Method are as follows: to the grating being horizontally mounted, if the center of a certain pixel of matrix falls within the upper of some blade of grating
Between lower edge, it is considered that the pixel is subordinated to this blade；To vertically arranged grating, if a certain pixel of matrix
Center is fallen between the left and right edges of some blade of grating, it is considered that the pixel is subordinated to this blade；If this leaf
State (open or close) of the piece at pixel is consistent with the state (0 or 1) of expected matrix, then it is assumed that this pixel is normal, on the contrary
Then think abnormal.
8. Ziye according to claim 5 divides control method, which is characterized in that the step of Optimized Segmentation:
S7: from practical subdivision matrix adjusted in the step S6 is subtracted in total subdivision matrix, obtaining new subdivision matrix, weight
Multiple step S4-S5, until new subdivision matrix is 0；
S8: to all Ziyes of above-mentioned steps, its weight is optimized using least square method, guarantees final segmentation result
It is minimum with expected matrix in step 1, complete segmentation.
9. Ziye according to claim 5 divides control method, which is characterized in that further include adjustment segmentation intensity value, subtract
The step of few total MU:
S7: calculating the area of practical subdivision matrix in the step S6, and the product with this area and segmentation intensity value is evaluation mark
It is quasi-；If the product value after current segmentation is greater than the product value of last segmentation, then the segmentation in the step S4 is strong
Angle value subtracts one, solves the matrix of this segmentation, repeats step S5-S6；Conversely, then carrying out step S8；
S8: from practical subdivision matrix in the step S6 is subtracted in total subdivision matrix, new subdivision matrix is obtained, repeats step
S4-S7, until new subdivision matrix is 0；
S9: to all Ziyes of above-mentioned steps, its weight is optimized using least square method, guarantees final segmentation result
It is minimum with expected matrix in step 1, complete segmentation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811577792.3A CN110170109B (en) | 2018-12-21 | 2018-12-21 | Orthogonal double-layer grating device for radiotherapy equipment and subfield segmentation control method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201811577792.3A CN110170109B (en) | 2018-12-21 | 2018-12-21 | Orthogonal double-layer grating device for radiotherapy equipment and subfield segmentation control method thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110170109A true CN110170109A (en) | 2019-08-27 |
| CN110170109B CN110170109B (en) | 2020-12-18 |
Family
ID=67689346
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201811577792.3A Active CN110170109B (en) | 2018-12-21 | 2018-12-21 | Orthogonal double-layer grating device for radiotherapy equipment and subfield segmentation control method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110170109B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111053977A (en) * | 2019-12-20 | 2020-04-24 | 上海联影医疗科技有限公司 | Multi-leaf collimator and radiotherapy device |
| CN112043974A (en) * | 2020-09-08 | 2020-12-08 | 苏州雷泰医疗科技有限公司 | Dynamic intensity modulation method and device based on orthogonal double-layer grating rotary sweep |
| WO2021248837A1 (en) * | 2020-06-08 | 2021-12-16 | 苏州雷泰医疗科技有限公司 | Quadrant division-based dynamic intensity-modulated segmentation method for double-layer orthogonal grating |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2445754Y (en) * | 2000-09-07 | 2001-09-05 | 大连现代高技术发展有限公司 | Multi-vane grating diaphragm for tumor radiotherapy |
| CN1635423A (en) * | 2003-12-29 | 2005-07-06 | Ge医疗系统环球技术有限公司 | Collimator, X-ray irradiation device and X-ray photography device |
| CN101499326A (en) * | 2009-01-22 | 2009-08-05 | 中国科学技术大学 | Static intensity modulating blade sequence algorithm of multi-diaphragm collimator |
| CN104436450A (en) * | 2013-09-25 | 2015-03-25 | 苏州雷泰医疗科技有限公司 | Light limiting device for radiotherapy device and radiotherapy device |
| WO2016058838A1 (en) * | 2014-10-13 | 2016-04-21 | Koninklijke Philips N.V. | Grating device for phase contrast and/or dark-field imaging of a movable object |
| CN108175953A (en) * | 2017-12-29 | 2018-06-19 | 苏州雷泰医疗科技有限公司 | A kind of strong optimization method of rotation tune and radiotherapy equipment based on dynamic raster |
-
2018
- 2018-12-21 CN CN201811577792.3A patent/CN110170109B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2445754Y (en) * | 2000-09-07 | 2001-09-05 | 大连现代高技术发展有限公司 | Multi-vane grating diaphragm for tumor radiotherapy |
| CN1635423A (en) * | 2003-12-29 | 2005-07-06 | Ge医疗系统环球技术有限公司 | Collimator, X-ray irradiation device and X-ray photography device |
| CN101499326A (en) * | 2009-01-22 | 2009-08-05 | 中国科学技术大学 | Static intensity modulating blade sequence algorithm of multi-diaphragm collimator |
| CN104436450A (en) * | 2013-09-25 | 2015-03-25 | 苏州雷泰医疗科技有限公司 | Light limiting device for radiotherapy device and radiotherapy device |
| WO2016058838A1 (en) * | 2014-10-13 | 2016-04-21 | Koninklijke Philips N.V. | Grating device for phase contrast and/or dark-field imaging of a movable object |
| CN108175953A (en) * | 2017-12-29 | 2018-06-19 | 苏州雷泰医疗科技有限公司 | A kind of strong optimization method of rotation tune and radiotherapy equipment based on dynamic raster |
Non-Patent Citations (1)
| Title |
|---|
| 齐东洲: "调强适形反射治疗计划（IMRT）中若干优化问题的研究", 《中国优秀硕士学位论文全文数据库医药卫生科技辑》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111053977A (en) * | 2019-12-20 | 2020-04-24 | 上海联影医疗科技有限公司 | Multi-leaf collimator and radiotherapy device |
| CN111053977B (en) * | 2019-12-20 | 2022-08-16 | 上海联影医疗科技股份有限公司 | Multi-leaf collimator and radiotherapy device |
| WO2021248837A1 (en) * | 2020-06-08 | 2021-12-16 | 苏州雷泰医疗科技有限公司 | Quadrant division-based dynamic intensity-modulated segmentation method for double-layer orthogonal grating |
| CN112043974A (en) * | 2020-09-08 | 2020-12-08 | 苏州雷泰医疗科技有限公司 | Dynamic intensity modulation method and device based on orthogonal double-layer grating rotary sweep |
| CN112043974B (en) * | 2020-09-08 | 2021-07-06 | 苏州雷泰医疗科技有限公司 | Dynamic intensity modulation method and device based on orthogonal double-layer grating rotary sweep |
| WO2022052324A1 (en) * | 2020-09-08 | 2022-03-17 | 苏州雷泰医疗科技有限公司 | Dynamic intensity modulation method and apparatus based on orthogonal double-layer grating rotary sweeping |
Also Published As
| Publication number | Publication date |
|---|---|
| CN110170109B (en) | 2020-12-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110170109A (en) | The orthogonal double-deck grating device and its Ziye for radiotherapy apparatus divide control method | |
| CN109310880B (en) | Trajectory optimization using slices in radiation therapy | |
| US11964170B2 (en) | Standardized artificial intelligence automatic radiation therapy planning method and system | |
| US9511241B2 (en) | Irradiation planning for particle therapy | |
| US11291856B2 (en) | Method, a computer program product and a computer system for radiotherapy | |
| CN105031819A (en) | Dosage optimization method and system | |
| CN111028914A (en) | Artificial intelligence guided dose prediction method and system | |
| CN110237439B (en) | Static intensity modulated subfield optimization method for orthogonal double-layer grating device | |
| US20220047893A1 (en) | Dynamic intensity-modulated segmentation method for orthogonal double-layer grating device | |
| US11833370B2 (en) | Methods and systems for irradiation based on a fluence map | |
| CN106682409B (en) | Sampling method, radiotherapy plan optimization method and dose calculation method | |
| CN110404185A (en) | A kind of strong dividing method of rotation tune and device of orthogonal double-layer grating | |
| US20180111005A1 (en) | Method of selecting beam geometries | |
| CN110215623A (en) | The orthogonal double-deck grating rotating tune based on Ziye optimization strong implementation method and device | |
| CN110248701A (en) | Thermal starting initialization to external beam radiation therapy planning optimization | |
| CN103706044A (en) | Design method for radiotherapeutic plan | |
| CN102024097A (en) | Target spot layout optimization method in treatment plan and treatment plan system | |
| CN108109678B (en) | Method, apparatus and computer-readable storage medium for determining an irradiation distribution for arc radiotherapy | |
| CN107961447B (en) | Method and device for obtaining radiotherapy plan | |
| CN110582325B (en) | System for ion-based radiotherapy treatment planning | |
| CN106503429B (en) | Sampling method and radiotherapy plan optimization method | |
| Song et al. | Dosimetric effects of gantry angular acceleration and deceleration in volumetric modulated radiation therapy | |
| US20240082602A1 (en) | A method of ion pbs treatment optimization, computer program product and computer system for performing the method | |
| Nguyen et al. | The optimization of intensity modulated radiotherapy in cases where the planning target volume extends into the build-up region | |
| CN118022201A (en) | VMAT-based blocking method and equipment for organ-at-risk illumination |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |