Quasi-IMAT Study with Conventional Equipment to Show High Plan Quality with a Single Gantry Arc

Overview

Journal Strahlenther Onkol

Specialties Oncology
Radiology

Date 2009 Feb 19

PMID 19224146

Citations 9

Authors

Judith Alvarez Moret

Oliver Kolbl

Ludwig Bogner

Affiliations

Soon will be listed here.

Abstract

Background And Purpose: : Nowadays, intensity-modulated arc therapy (IMAT) for clinical use is mostly based on forward planning. The aim of this work is to investigate the potential of a step-and-shoot quasi-IMAT (qIMAT) technique to improve plan quality.

Material And Method: : qIMAT plans with 18 and 36 beams were generated with a total number of 36 segments. Additionally, the number of segments was increased to 72, in order to investigate if the quality of the plans improves with the number of beams and segments. A conventional six-field intensity-modulated radiation therapy (IMRT) plan was used as a reference. The beam setup was applied to the CarPet phantom and to five prostate cancer patients.

Results: : In the phantom case, the dose received by the organ at risk (OAR) decreased considerably by using qIMAT. At the same time, coverage and homogeneity of planning target volume (PTV) remained unaffected. For the prostate cases, a good dose coverage was accomplished inside the PTV. Rectum and bladder were better spared with qIMAT. When increasing the number of segments, only a slight improvement of the plan quality was observed.

Conclusion: : The study showed that qIMAT improves the sparing of OARs while keeping the uniformity within the PTV, when compared with conventional IMRT. The more concave the PTV, the more noticeable is this behavior. The qIMAT technique has the advantage that it can be realized with a conventional equipment. The plan quality is high even with a single gantry arc and one segment per beam direction.

Citing Articles

Erratum to: Evolution of educational inequalities in mortality among young adults in an urban setting.

De Grande H, Deboosere P, Vandenheede H Int J Public Health. 2015; 60(3):399-400.

PMID: 25675940 DOI: 10.1007/s00038-015-0662-2.

Commissioning and first clinical application of mARC treatment.

Dzierma Y, Nuesken F, Kremp S, Palm J, Licht N, Rube C Strahlenther Onkol. 2014; 190(11):1046-52.

PMID: 24777584 DOI: 10.1007/s00066-014-0662-9.

Quasi-VMAT in high-grade glioma radiation therapy.

Fadda G, Massazza G, Zucca S, Durzu S, Meleddu G, Possanzini M Strahlenther Onkol. 2013; 189(5):367-71.

PMID: 23549780 DOI: 10.1007/s00066-012-0296-8.

Fast IMRT by increasing the beam number and reducing the number of segments.

Bratengeier K, Gainey M, Flentje M Radiat Oncol. 2011; 6:170.

PMID: 22152490 PMC: 3377925. DOI: 10.1186/1748-717X-6-170.

Impact of gantry rotation time on plan quality and dosimetric verification--volumetric modulated arc therapy (VMAT) vs. intensity modulated radiotherapy (IMRT).

Pasler M, Wirtz H, Lutterbach J Strahlenther Onkol. 2011; 187(12):812-9.

PMID: 22127360 DOI: 10.1007/s00066-011-2263-1.

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