Award Date


Degree Type

Doctoral Project

Degree Name

Doctor of Medical Physics (DMP)


Health Physics and Diagnostic Sciences

First Committee Member

Steen Madsen

Second Committee Member

Yu Kuang

Third Committee Member

Cephas Mubata

Fourth Committee Member

Ali Soleimani-Meigooni

Fifth Committee Member

Ryan Hecox

Sixth Committee Member

Brach Poston

Number of Pages



HyperArc is a radiation therapy planning technique using stereotactic radiosurgical doses delivered via single isocenter volumetric modulated arcs (VMAT) for multi-lesion brain cancer. Due to the nature of these types of treatments it is imperative that the proper quality assurance is completed to ensure the safety of the patient. Geometric limits were assessed using a dose volume histogram (DVH) and known rotational errors of theoretical lesions of different dimensions and lengths from the isocenter. Dosimetric comparisons were evaluated using an ion chamber and Gafchromic EBT-XD film and portal dosimetry. The conclusions from these investigations were that patient rotation will result in a loss of target coverage, which is emphasized for smaller targets and isocenter placement farther away from the lesion. The use of a six degree of freedom (6DoF) couch for set-up and surface tracking during beam delivery reliably positions patients to avoid positioning errors that would degrade treatment outcomes. HyperArc is a user-friendly clinical tool that can be confidently used in a clinical setting when the limitations are well known to the user.


LINAC-SRS; Radiation Therapy; set-up error; single isocenter multiple target technique; stereotactic radiosurgery (SRS); VMAT


Medicine and Health Sciences

File Format


File Size

1168 KB

Degree Grantor

University of Nevada, Las Vegas




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