Nels C. Knutson, PhD, MS

Modern linear accelerators maintain precise control of delivery parameters during the treatment of dynamic external beam radiotherapy treatment plans; vendors provide snapshots of these parameters using trajectory log files (TLF). This project aims to investi...

To perform comprehensive dosimetric validation of a commercially available independent Monte Carlo (MC)-based secondary dose calculation engine for clinical photon radiotherapy.

To develop and validate a novel isocentricity test using continuous axis motion and imaging during beam delivery to characterize three-dimensional isocenter walkout.

To validate an online adaptive radiotherapy (oART) workflow for a C-arm linear accelerator (LINAC) equipped with HyperSight CBCT using Imaging and Radiation Oncology Core (IROC) anthropomorphic phantoms.

Despite the global transition toward more precise and conformal radiotherapy, many countries currently treat with Co-60 units. This paper describes key steps, challenges and lessons learned from a successful transition from Co-60 to LINAC based radiotherapy i...

In the Phase I clinical trial (NCT05831579), we already performed the palliative spatially fractionated (GRID) proton therapy by using a collimating brass aperture. However, the existence of this brass aperture limits the flexibility of the high dose regions...

A novel, low-cost 3D surface scanning system was developed using a custom modification of the laser-profiling technique. Proof of concept was demonstrated through 3D simulation in Blender 3D software. A real-world prototype was then implemented using a consum...

To develop and validate a continuous two-dimensional output-factor (OF) model and to identify a measurement strategy that achieves accuracy and efficiency.

Stereotactic arrhythmia radiotherapy (STAR) is an emerging treatment for ventricular tachycardia (VT) that uses radiation to modulate cardiac electrophysiology (EP) and reduce VT. Registering radiation planning 3D imaging to cardiac optical maps will enable o...

Large-animal studies of stereotactic arrhythmia radiotherapy (STAR) are faced with financial and logistical difficulties that limit widespread implementation. We developed a single-platform STAR porcine workflow on an O-ring linac utilizing manual end-exhalat...

Gamma Knife radiosurgery (GKRS) has undergone multiple technological transitions over the past two decades. This study evaluates long-term utilization trends at a single academic institution to assess whether GKRS has remained a durable and adaptable treatmen...

Independent verification of IROC phantom credentialing results is valuable for institutional quality assurance and confidence in treatment planning system performance. This work aimed to verify the accuracy of a commercially available Monte Carlo (MC) dose al...

Clinical Trials Specialty Program