Type of System

Name of System

Name of Author

Name of Study

Name of Exhibition


Radiotherapy &
Radiosurgery -
(press reports)


Accuknife


FDA


"FDA Clears Direx Accusoft For Intensity Modulated Radiation Therapy (IMRT)"





INTENSITY MODULATED RADIOTHERAPY ON
TREATMENT OF BRAIN TUMORS –
DYNAMIC ARC TECHNIQUE WITH MICROMULTILEAF (IMAT)



The use of intensity modulated radiotherapy with dynamic arc technique and micromultileaf (IMAT) allow excellent modulation of target volume and great security on radiation delivery on brain tumors as demonstrated below.

 

Delineation and isodose curves on recurrent meningioma.

 

Dose Volume Histogram of target and normal surrounding tissues.

 

Three dimensional reconstruction of target and normal surrounding tissues.

 

Beam Eye View of target with micromultileaves.

Acknowledgment:
Instituto do Radium de Campinas
Carlos Roberto Monti, PhD.
Ricardo Akiyoshi Nakamura, MD.
Leandro Federiche Borges, Physicist.

 

 

 

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RADIOSURGERY ASSOCIATED WITH INTENSITY MODULATED RADIOTHERAPY ON CEREBRAL METASTASIS –
DYNAMIC ARC TECHNIQUE WITH MICROMULTILEAF (IMAT)



Radiosurgery with dynamic arc technique associated with micromultileaf and intensity modulated radiotherapy (IMAT) use the same patterns of imobilization and normal tissues and target delineation as radiosurgery with cone. However, IMAT permit irradiation with a single isocenter and not require the necessity of several positions of table and gantry of linear accelerator during the treatment, minimizing time and risk of wrong setup.

 

Delineation and isodose curves on breast cancer cerebral metastasis.

 

Dose Volume Histogram of target and normal surrounding tissues.

 

Three dimensional recontruction of target and normal surrounding tissues.

 

Beam Eye View of target with micromultileaves.

Acknowledgment:
Instituto do Radium de Campinas
Carlos Roberto Monti, PhD.
Ricardo Akiyoshi Nakamura, MD.
Leandro Federiche Borges, Physicist.

 

 

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COMPARISON BETWEEN INTENSITY,br>MODULATED RADIOTHERAPY WITH DYNAMIC ARC TECHNIQUE (IMAT) AND CONVENTIONAL THREE DIMENSIONAL RADIOTHERAPY
(3DCRT) ON TREATMENT OF PROSTATE CANCER.



On IMAT technique, the delineation of structures on tomographic slices is performed as on conventional three dimensional radiotherapy (3DCRT) (Figures 1 and 2). However, dynamic arcs are defined with conformation of target volume with micromultileaves (Figure 3), and different priorities on target and on normal surrounding tissues are performed. Dose Volume Histograms (DVH) are generated to evaluate doses on rectum, bladder and target volume, and a comparison between 5 static fields of 3DCRT and four dynamic arcs of IMAT are done (Figure 4 to 6).

 

Figure 1.
Delineation of structures and isodose curves on target volume.

 

Figure 2.
Three dimensional reconstruction of target volume and normal surrounding tissues.

 

Figure 3.
Beam Eye View with micromultileaves.

 

Figure 4.
DVH Target: IMAT demonstrated more heterogeneity than 3DCRT.



Figure 5.
DVH Rectum: IMAT better than 3DCRT.

 

Figure 6.
DVH Bladder: IMAT better than 3DCRT


IMAT demonstrated more heterogeneity than 3DCRT on target volume, however, this is not an inacceptable characteristic and doses of radiation on rectum and bladder were substantially reduced becoming IMAT a treatment option more interesting on prostate cancer than 3DCRT.

Acknowledgment:
Instituto do Radium de Campinas
Carlos Roberto Monti, PhD.
Ricardo Akiyoshi Nakamura, MD.
Felipe Amstalden Trevisan, MD.

 

 

fda



Natick, MA, July 13, 2004


FDA clears Direx Accusoft for
Intensity Modulated Radiation Therapy (IMRT)


Direx Systems Corporation announced that it has received FDA clearance for an expanded application of the AccuSoft to include Intensity Modulated Radiation Therapy (IMRT). AccuSoft is the treatment planning system of AccuKnife, a family of advanced products for the radiation treatment of cancer.

AccuKnife upgrades medical linear accelerators, currently operating in hospitals and cancer clinics, to stereotactic radiosurgery (SRS), conformal 3D radiation therapy, and intensity modulated radiation therapy (IMRT). In addition to AccuSoft, AccuKnife includes AccuLeaf, a unique 4-bank multi-leaf collimation system, providing the highest resolution field definition in clinical radiation therapy.

AccuSoft is a PC-based system featuring image-based planning with proprietary convolution calculation algorithms resulting in fast dose calculation together with accurate representation of the radiation dose distribution. AccuSoft includes both forward and inverse treatment planning, full 3D imaging and dose display, stream-lined commissioning protocol, and DICOM network compatibility. In addition, the AccuLeaf supports the unique 4-bank collimator geometry of the AccuLeaf multi-leaf collimator.

Direx will exhibit the AccuSoft treatment planning system and other radiotherapy products at the AAPM 2004 meeting in Pittsburgh, PA (booth number 132), the ASTRO 2004 meeting in Atlanta, GA and the ESTRO 2004 meeting in Amsterdam and JASTRO 2004 in Chiba, Japan.