Controlled mold geometry for surgical deficit treatment planning. Academic Article uri icon

Overview

abstract

  • The relatively precise placement of brachytherapy sources afforded by stereotactic frames for brain implants is not generally achievable for other sites, which lack the fixed geometry of the cranium and its contents. An exception is a source-containing rigid mold that delivers brachytherapy when inserted securely in a surgical defect. A technique has been developed in which an acrylic mold of the region to be treated is suspended in a demountable aluminum box, which is then filled to a suitable level with dental stone to form a casting that supports the mold and that can be removed intact. First, the box is aligned on a mill table and a ball mill is used to drill three parallel holes in the acrylic mold, with precisely known locations and depths and as widely separated as possible. The spherical air cavities that result from plugging these holes with ball-milled acrylic rods become reference markers in subsequent computed tomography (CT) scans. After optimum CT-coordinate locations have been planned for 125I seeds in catheters, they are transformed to mill coordinates using a matrix developed from the known marker coordinates in the two systems. Catheter holes are then drilled with the mold in the reassembled casting and box. The method has been used to treat both recurrent maxillary cancer and recurrent orbital rhabdomyosarcoma.

publication date

  • March 1, 1995

Research

keywords

  • Brachytherapy
  • Radiotherapy Planning, Computer-Assisted

Identity

Scopus Document Identifier

  • 0028964480

Digital Object Identifier (DOI)

  • 10.1118/1.597454

PubMed ID

  • 7596320

Additional Document Info

volume

  • 22

issue

  • 3