Integrated Registration Software

– Clinical interest in Radiosurgery

of brain AVMusing cyberknife

ANXIONNAT R, DERELLE AL, PICARD L, BRACARD SDiagnostic and interventional neuroradiology, Nancy France

BUCCHEIT I, BERNIER VAnticancerous center, Nancy France

CHONDROU C, WIMILLE B, TROUSSET YGE Healthcare, Buc france

Cyberknife • Robotic arm• X-ray verification system• Frameless nonisocentric

linac-based system• 3D imaging only

• Anticancerous center since January 2007

• Radiosurgery of brain AVMs since july 2010

Delineation of the nidus

• Linac (before 2010)• Brainlab• Stereotactic frame

• Registration sofware brainscan

• 3DCT,3DMR, 2DSA

• Delineation on 2DSA and refinement on MRI (brain parenchyma)

• Cyberknife (since 2010)• Accuray • Frameless

• Integrated registration software (GE Healthcare)

• 3DCT, 3DMR, 3DXA

• Delineation on 3DXA and refinement on MRI (brain parenchyma)

3D X-ray angiography• Innova 3131 – 40°/sec

– 3D volume– high spatial resolution 200

microns

• Shape of the nidus and analysis of the angioarchitecture on AW workstation– Oblique views– Multiplanar reformations

3DXA in brain AVMs• Better understanding of the angioarchitecture

– Anxionnat R et al. 3D angiography. Clinical interest. First applications in interventional neuroradiology. J Neuroradiol 1998

– Kakizawa et al. Compartments in arteriovenous malformation nidi demonstrated with rotational three-dimensional digital subtraction angiography by using selective microcatheterization. Report of three cases. J Neurosurg 2002

– Prestigiacomo et al. Three-dimensional rotational spinal angiography in the evaluation and treatment of vascular malformations. AJNR 2003

• Delineation of the nidus prior to radiosurgery– Berger, Anxionnat, Kerrien, Picard and Sodermann. A

methodology for validating a 3D imaging modality for brain AVM delineation : application to 3DRA. Computerized Medical Imaging and Graphics 2008; 32,544-53

– Colombo et al. Three dimensional angiography for radiosurgical treatment planning for arteriovenous malformations. J Neurosurg 2003;98, 536-43

3DXA analysis of the nidus on AW workstation

3DXA analysis of the nidus

Global shape Shunting zones inside the nidus

Segmentation of the nidus using 3D scalpel on multiple oblique reformated views

Progressive refinement of the segmentation on oblique views (including axial one)

20% decrease of nidus volume

Initial volume (Frontal +sagittal)

Final volume (+oblique views)

Integrated registration software• Multimodality frameless registration and

fusion software– 3DXA, 3DMRI Gd+, 3DCT– 3D nidus segmentation, … (organs at risk …)

• Automatic registration– Manual refinement if necessary

• Post processing tools – Visualisation– Drawing tools– Volume measurement …

Registration accuracy• Visualisation tools : transparency,

checkglass ….• Common points on anatomic landmarks

– Bone structures for CT-XA registration– Vessels for XA-MR registration

XA-MR Registration

Refinement of nidus segmentation

using integrated registration • 3DXA, 3DMRI, 3DCT,

nidus volume segmented from 3DXA are co-registered

• Refinement of the nidus segmentation by delineation slice by slice

Refinement of the delineation slice by slice on coregistered 3DXA and 3DMR

Clinical interest of this new method of target delineation

• 9 brain AVMs treated by radiosurgery using LINAC and brainlab (2009) : delineation of the target on 2DSA and MRI (volume 1)

• New method of the target in these 9 AVMs using 3DXA and integrated registration (volume 2)

• Comparaison of the volume size between the 2 methods of delineation: decrease of the target volume

Conclusion• Use of 3DXA in the delineation of the

nidus and integrated registration software– Accuracy and speed of the registration +++– Better visualization of the nidus– Better delineation of the nidus

• 3D segmentation on multiple oblique views (global shape)

• Refined slice by slice

• Better conformity to the nidus in a reduced target volume

Work in progress• Improvement in drawing tools :

– Semi-automatic (snakes …)– 3D tools

• Integration of functional imaging (activation MR, tractography)

• Improvement of 3DXA– Subtraction– Faster rotation