# US 9,437,339 B2 · Leaf assembly for a multi-leaf collimator and multi-leaf collimator

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 9,437,339 B2
- Document ID: US9437339B2
- Status: Granted
- Kind: B2
- Application number: 14/415,086
- Filed: 2013-07-18
- Published: 2015-07-23
- Granted: 2016-09-06
- Earliest claimed: 2012-07-19
- Assignees: Deutsches Krebsforschungszentrum; Precisis AG
- Applicants: Deutsches Krebsforschungszentrum; Precisis AG
- Inventors: Gernot Echner
- Web page: https://patentgrep.com/patent/US9437339B2

## CPC

- G21K 1/046: {varying the contour of the field, e.g. multileaf collimators}
- A61N 5/1045: {using a multi-leaf collimator, e.g. for intensity modulated radiation therapy or IMRT}
- G21K: HANDLING OF PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR; IRRADIATION DEVICES; GAMMA RAY OR X-RAY MICROSCOPES
- A61N: ELECTROTHERAPY; MAGNETOTHERAPY; RADIATION THERAPY; ULTRASOUND THERAPY (measurement of bioelectric currents A61B; surgical instruments, devices or methods for transferring non-mechanical forms of energy to or from the body A61B18/00; anaesthetic apparatus in general A61M; incandescent lamps H01K; infrared radiators for heating H05B)

## Abstract

The invention relates to a leaf assembly (102) for a multi-leaf collimator, comprising a leaf frame (104) and a plurality of leaves (106) for shielding beams (108) from a selected area, wherein the leaves (106) are arranged sideways and adjacently in the leaf frame (104) for shielding beams (108) being emitted from a radiation source (110) located above the assembly (102), wherein each leaf (106) is mounted in the leaf frame (104) displaceably in an adjusting direction (112) being oriented perpendicularly related to said beams (108), and wherein the leaf frame (104) provides a linear guidance (114) for each leaf (106) within the adjusting direction (112), being designed in a such a way that the leaf frame (104) is adapted to allow for lateral movement of the leaves (106) superposing said linear guidance (114), thus allowing mutual abutting of the leaves (106). Furthermore, the invention relates to a multi-leaf collimator comprising two leaf assemblies (102) according to the invention, wherein the assemblies (102) are arranged to face each other within the adjusting direction (112). The invention is based on the objective of designing a leaf assembly (102) for a multi-leaf collimator and a multi-leaf collimator in such a way that the occurrence of leak-age radiation may be diminished.

## Claims

### Claim 1

A leaf assembly for a multi-leaf collimator, comprising a leaf frame and a plurality of leaves for shielding beams from a selected area,
wherein the leaves are arranged sideways and adjacently in the leaf frame for shielding beams being emitted from a radiation source located above the assembly,
wherein each leaf is mounted in the leaf frame displaceably in an adjusting direction being oriented perpendicularly related to the beams,
wherein the leaf frame provides a linear guidance for each leaf within the adjusting direction, and
wherein the leaf frame is configured to allow for lateral movement of the leaves superposing the linear guidance, thereby allowing mutual abutting of the leaves.

### Claim 2 (depends on 1)

The leaf assembly according to claim 1, wherein the leaves have a conical cross-sectional area.

### Claim 3 (depends on 1)

The leaf assembly according to claim 1, wherein the lateral movement allowed for by the leaf frame comprises an increment of an inclined upward movement of the leaves.

### Claim 4 (depends on 1)

The leaf assembly according to claim 1, wherein the linear guidance is provided by grooves in the leaf frame which extend longitudinally in the adjusting direction.

### Claim 5 (depends on 4)

The leaf assembly according to claim 4, wherein a depth of the grooves allows for an upward movement of the leaves.

### Claim 6 (depends on 4)

The leaf assembly according to claim 4, wherein the grooves are tilted with respect to the beams emitted from the radiation source located above the assembly.

### Claim 7 (depends on 1)

The leaf assembly according to claim 1, further comprising laterally flexible elements arranged between the leaf frame and the leaves.

### Claim 8 (depends on 7)

The leaf assembly according to claim 7, wherein the laterally flexible elements comprise spring steel elements.

### Claim 9 (depends on 1)

The leaf assembly according to claim 1, wherein the linear guidance provided by the leaf frame is configured to interact with one side of the leaves, whereas the opposite side of the leaves is tiltable, allowing mutual abutting of the leaves.

### Claim 10 (depends on 9)

The leaf assembly according to claim 9, wherein the linear guidance comprises rounded grooves in the leaf frame which extend longitudinally in the adjusting direction.

### Claim 11 (depends on 1)

A multi-leaf collimator, comprising two leaf assemblies according to claim 1, wherein the two leaf assemblies are arranged to face each other within the adjusting direction.