Thesis Defense 
Title: Optimized and Integrated Alignment System for Functional Proton Radiosurgery
By: Fadi Easa Shihadeh

Where: ??
When: 2pm Wednsday 23rd of May 2007

Advisor: Dr. Keith Evan Schubert
Committee: Dr. Reinhard Schulte, Dr. Arturo Concepcion, Dr. Ernesto Gomez

Abstract:
Radiosurgery is a non-invasive treatment technique applying focused
radiation beams. It requires high geometric accuracy as misalignment can
cause damage to the surrounding healthy tissues and loss of the therapeutic
effect. One promising technique to ensure sub-millimeter alignment accuracy
of the radiation beam is to optically monitor the position of the beam axis
relative to a frame firmly attached to the patient's skull using an optical
alignment system. The optical alignment method requires an Optical
Localization System (OLS) and a marker system visible to the OLS in order to
derive three-dimensional coordinate transforms needed to align the proton
beam axis to its stereotactic target. Once the target and the proton beam
are defined in the same coordinate system, an alignment control system can
be used to align the beam to the target. In this thesis work, a system for
proton beam alignment was studied and optimized in many of its functional
areas. The resulting system was named Positioning Alignment Control System
(PACS). The PACS system is an integrated and efficient system as a result of
the work done on it in the course of this thesis work.