Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
  • A61B6/54—Control of apparatus or devices for radiation diagnosis
  • A61B6/541—Control of apparatus or devices for radiation diagnosis involving acquisition triggered by a physiological signal
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B5/00—Measuring for diagnostic purposes; Identification of persons
  • A61B5/08—Measuring devices for evaluating the respiratory organs
  • A61B5/0816—Measuring devices for examining respiratory frequency
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
  • A61B6/02—Arrangements for diagnosis sequentially in different planes; Stereoscopic radiation diagnosis
  • A61B6/03—Computed tomography [CT]
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
  • A61B6/02—Arrangements for diagnosis sequentially in different planes; Stereoscopic radiation diagnosis
  • A61B6/03—Computed tomography [CT]
  • A61B6/032—Transmission computed tomography [CT]
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
  • A61B6/00—Apparatus or devices for radiation diagnosis; Apparatus or devices for radiation diagnosis combined with radiation therapy equipment
  • A61B6/04—Positioning of patients; Tiltable beds or the like
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
  • G06T12/00—Tomographic reconstruction from projections
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
  • G06T12/00—Tomographic reconstruction from projections
  • G06T12/10—Image preprocessing, e.g. calibration, positioning of sources or scatter correction
• • G—PHYSICS
  • G06—COMPUTING OR CALCULATING; COUNTING
  • G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
  • G06T2211/00—Image generation
  • G06T2211/40—Computed tomography
  • G06T2211/412—Dynamic

Definitions

• the present invention relates to scanning by computed tomography (CT).
• CT computed tomography
• CT scanning is a process for imaging the internal structure of a patient.
• a beam of x-rays is projected through the patient and its attenuation is measured.
• the apparatus is rotated about an axis passing longitudinally through the patient.
• data is acquired as to the attenuation of the beam in each direction in the plane in which rotation takes place.
• the internal structure of the patient on that plane can be computed.
• the patient or apparatus is then indexed along the axis and a further plane (known as a 'slice') is then investigated.
• a three dimensional image of the patient can then be constructed from the various slices.
• Breath control systems are available, intended for use in conventional CT scanning, and which could be used to monitor the patient's breathing.
• a feature in the projection image(s) to determine the breathing phase.
• a suitable feature is the position of the patient's diaphragm. This can then be used to select the relevant images to be used in the projection process.
• this feature in the projection images can be used to control delivery of therapeutic radiation dependent on the patient's breathing cycle, to ensure that the tumour is in the correct position when the radiation is delivered. This will provide a direct measure of the patient's breathing phase, a significant improvement as compared to current methods that use external markers affixed to the patient.
• the use of a 3D volume data set generated using the same patient position and contemporaneous with the treatment will remove significant uncertainties.
• the present invention further provides a radiotherapy device comprising a respiration correlated cone beam CT scanner and a source of therapeutic radiation, in which therapeutic radiation is delivered during the scan at times correlated with the patient's breathing cycle.
• Figure 1 is a view of a cone beam CT scanner according to the present invention, viewed along the axis of rotation thereof;
• Figure 2 is a schematic view of the system incorporating such a scanner.
• Figure 3 shows a treatment apparatus including the scanner of the present invention.
• Figure 1 shows a cone beam CT scanner.
• a patient 10 is supported on a couch 12 which may be of any suitable design.
• Couches typically allow the elevation and longitudinal position of the patient to be adjusted and this may be provided for as desired.
• An x-ray source 14 is arranged to project a wide beam 16 of radiation generally directed towards the isocentre 18 of the patient.
• the source 14 is rotatable around the isocentre 18 on a rotational support 20.
• the support can, for example, be in the form of a ring or annulus around the patient 10 and couch 12 in which the source is mounted, or it can be a C-arm, or any suitable support allowing the source to rotate, or any combination thereof.
• a two-dimensional flat-panel detector 22 is also mounted on the support 20, opposite the source 14 and arranged to rotate in synchronism therewith. If the support includes a C-arm then this can be achieved by mounting the detector on the opposite arm.
• the source 14 is partially absorbed by the patient and the attenuated signal is detected by the flat panel detector 22.
• the source 14 and detector 22 are then indexed rotationally and a fresh image obtained. This is repeated until sufficient images are acquired to reconstruct the volume data, typically one complete rotation.
• Figure 2 shows the system as a whole.
• the scanner of figure 1 is shown, together with cables linking the source 14, detector 22 and rotational support 20 to a plurality of computing means 24, 26 which process the data generated including the images, source intensity (etc), and rotational support position.
• Data is output via any suitable means, depicted generally as a monitor 28 but not limited thereto, and the system is controlled by any suitable input means, again depicted generally as a keyboard 30 but likewise not especially limited thereto.
• a breath control system is provided at 32 to monitor the phase of the patients breathing while the projection images are acquired.
• projection images that have comparable breathing phases can be selected from the complete set, and these are used to reconstruct the volume data using cone beam CT techniques.
• any phase or range of phases can be selected and therefore the effect of breathing can be studied if desired.
• breath control system it is possible to use a feature in the projection image(s) to determine the breathing phase, such as the position of the patient's diaphragm. This can then be used to select the relevant images to be used in the projection process.
• An alert system including a light 34 and a buzzer 36 is provided, to prompt the patient visually and audibly in order to ensure a regular amplitude and pattern of breathing.
• Other alerts could of course be employed, such as other forms of visible prompts including (for example) movable devices, and other forms of audible prompts including (for example) speakers, percussive devices or any other form of controllable sound generation apparatus.
• Figure 3 shows a system including a therapeutic source of radiation 38 arranged to emit a suitably collimated beam of therapeutic radiation 40. This allows simultaneous scanning and treatment. If the radiation from source 14 continues during the treatment the selected feature (above) in the projection images can be used to control delivery of therapeutic radiation from the source 38, dependent on the patient's breathing cycle. This ensures that the tumour is in the correct position when the radiation is delivered. This will provide a direct measure of the patient's breathing phase, a significant improvement as compared to current methods that use external markers affixed to the patient. The use of the same direct measure of the patient's breathing phase and patient position to generate the 3D volume data set and control the treatment delivery will remove significant uncertainties.

Landscapes

• Health & Medical Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Medical Informatics (AREA)
• Physics & Mathematics (AREA)
• General Health & Medical Sciences (AREA)
• Surgery (AREA)
• Veterinary Medicine (AREA)
• Public Health (AREA)
• Animal Behavior & Ethology (AREA)
• Biophysics (AREA)
• Pathology (AREA)
• Molecular Biology (AREA)
• Biomedical Technology (AREA)
• Heart & Thoracic Surgery (AREA)
• Radiology & Medical Imaging (AREA)
• Optics & Photonics (AREA)
• Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
• High Energy & Nuclear Physics (AREA)
• Pulmonology (AREA)
• Theoretical Computer Science (AREA)
• Physiology (AREA)
• General Physics & Mathematics (AREA)
• Apparatus For Radiation Diagnosis (AREA)
• Radiation-Therapy Devices (AREA)
• Analysing Materials By The Use Of Radiation (AREA)
• Image Processing (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (2)

Family

ID=9951464

Family Applications (1)

Country Status (6)

Cited By (4)

Families Citing this family (12)

Citations (7)

Family Cites Families (32)

• 2003
  • 2003-01-21 GB GB0301278A patent/GB2397738B/en not_active Expired - Lifetime
• 2004
  • 2004-01-20 EP EP04703444.2A patent/EP1589876B2/en not_active Expired - Lifetime
  • 2004-01-20 JP JP2006500227A patent/JP4499087B2/ja not_active Expired - Lifetime
  • 2004-01-20 WO PCT/GB2004/000220 patent/WO2004064641A1/en not_active Ceased
  • 2004-01-20 AT AT04703444T patent/ATE529044T1/de not_active IP Right Cessation
  • 2004-01-20 CN CNB2004800017740A patent/CN100484475C/zh not_active Expired - Lifetime
  • 2004-01-20 CN CNB2004800070367A patent/CN100410970C/zh not_active Expired - Fee Related

Patent Citations (7)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events