Abstract:
:Previous treatment of cerebrospinal fluid (CSF) malignancies by intrathecal administration of (131)I-radiolabelled monoclonal antibodies has led to the assumption that more healthy tissue will be spared when a pure beta-emitter such as (90)Y replaces (131)I. The purpose of this study is to compare and quantitatively evaluate the dose distribution from (90)Y to the CSF space and its surrounding spinal structures to (131)I. A 3D digital phantom of a section of the T-spine was constructed from the visible human project series of images which included the spinal cord, central canal, subarachnoid space, pia mater, arachnoid, dura mater, vertebral bone marrow and intervertebral disc. Monte Carlo N-particle (MCNP4C) was used to model the (90)Y and (131)I radiation distribution. Images of the CSF compartment were convolved with the radiation distribution to determine the dose within the subarachnoid space and surrounding tissues. (90)Y appears to be a suitable radionuclide in the treatment of central nervous system (CNS) malignancies when attached to mAb's and the dose distribution would be confined largely within the vertebral foramen. This choice may offer favourable dose improvement to the subarachnoid and surface of spinal cord over (131)I in such an application.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Mardirossian G,Hall M,Montebello J,Stevens Pdoi
10.1088/0031-9155/51/1/014subject
Has Abstractpub_date
2006-01-07 00:00:00pages
185-96issue
1eissn
0031-9155issn
1361-6560pii
S0031-9155(06)04538-6journal_volume
51pub_type
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