Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

The helical tomotherapy thread effect.

M W Kissick1, J Fenwick, J A James

  • 1Departments of Medical Physics and Engineering Physics, University of Wisconsin Medical School, Madison, Wisconsin 53706-1532, USA. mwkissick@wisc.edu

Medical Physics
|June 30, 2005
PubMed
Summary
This summary is machine-generated.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

[Ceasing to do what shouldn't be done].

Anales del sistema sanitario de Navarra·2018
Same author

[Level of knowledge of Quality Commitment Campaign and of "do not do" recommendations amongst general practitioners, pediatricians and nurses Primary Care].

Anales del sistema sanitario de Navarra·2018
Same author

Response to "Comment on 'Monte Carlo evaluation of the convolution∕superposition algorithm of Hi-Art<sup>TM</sup> tomotherapy in heterogeneous phantoms and clinical cases' " [Med. Phys., (2009)].

Medical physics·2017
Same author

WE-E-BRB-05: A Novel Detector Dose Calculation Model for in Vivo Delivery Verification of IMRT Treatments.

Medical physics·2017
Same author

[Proposals for the study of the second victim phenomenon in Spanish Primary Care Centres and Hospitals].

Revista de calidad asistencial : organo de la Sociedad Espanola de Calidad Asistencial·2016
Same author

In Vivo Verification as a Tool to Tailor Daily IGRT and Flag Adaptive Radiotherapy.

Practical radiation oncology·2014
Same journal

Correction to "On the shape of the radiation survival curve in tumor spheroids: The role of oxygen heterogeneity".

Medical physics·2026
Same journal

Multi-view constrained semi-supervised vertebra detection for 3D ultrasound spine volume.

Medical physics·2026
Same journal

Accuracy of quantitative <sup>177</sup>Lu SPECT/CT imaging: A systematic review.

Medical physics·2026
Same journal

Physics-constrained dual-domain network for CBCT reconstruction from orthogonal X-rays in gynecologic radiotherapy.

Medical physics·2026
Same journal

Decomposition-based harmonization for quantitative PET imaging across scanners and radiotracers.

Medical physics·2026
Same journal

Development and evaluation of an in vivo dose-based monitoring system for electron FLASH radiation therapy.

Medical physics·2026
See all related articles

Helical tomotherapy exhibits a unique "ripple" dose variation due to beam junctioning. Minima for this ripple occur near specific pitch values, offering potential for dose reduction in certain radiotherapy cases.

Area of Science:

  • Medical Physics
  • Radiation Oncology

Background:

  • Helical tomotherapy generates a characteristic dose variation pattern known as "ripple."
  • This ripple arises from the unique helical beam junctioning process inherent to this technology.

Purpose of the Study:

  • To investigate the relationship between pitch, beam width, and ripple magnitude in helical tomotherapy.
  • To identify conditions and strategies for minimizing dose variations in helical tomotherapy treatments.

Main Methods:

  • Utilized a convolution-superposition dose calculator to model ripple magnitude.
  • Explored ripple variations with changes in pitch and beam width.
  • Validated findings with benchmark measurements.

Main Results:

Related Experiment Videos

  • Analytical models and simulations predicted ripple minima near pitches of 1/n (where n is an integer).
  • Empirical measurements confirmed sharp ripple minima around p=0.86(1/n), influenced by off-axis profiles and scatter.
  • The ripple effect is generally small for typical helical tomotherapy parameters.

    • Conclusions:

    • Minimizing ripple in helical tomotherapy can be achieved by selecting specific pitch values or employing "double threading" (180-degree out-of-phase delivery).
    • While often clinically insignificant, ripple mitigation may benefit extreme cases, such as large fields or high pitches.