Beam’s-eye-view dosimetrics (BEVD) guided rotational station parameter optimized radiation therapy (SPORT) planning based on reweighted total-variation minimization

Conventional VMAT optimizes aperture shapes and weights at uniformly sampled stations, which is a generalization of the concept of a control point. Recently, rotational station parameter optimized radiation therapy (SPORT) has been proposed to improve the plan quality by inserting beams to the regions that demand additional intensity modulations, thus formulating nonuniform beam sampling. This work presents a new rotational SPORT planning strategy based on reweighted total-variation (TV) minimization (min.), using beam’s-eye-view dosimetrics (BEVD) guided beam selection. The convex programming based reweighted TV min. assures the simplified fluence-map, which facilitates single-aperture selection at each station for single-arc delivery. For the rotational arc treatment planning and non-uniform beam angle setting, the mathematical model needs to be modified by additional penalty term describing the fluence-map similarity and by determination of appropriate angular weighting factors. The proposed algorithm with additional penalty term is capable of achieving more efficient and deliverable plans adaptive to the conventional VMAT and SPORT planning schemes by reducing the dose delivery time about 5 to 10 s in three clinical cases (one prostate and two head-and-neck (HN) cases with a single and multiple targets). The BEVD guided beam selection provides effective and yet easy calculating methodology to select angles for denser, non-uniform angular sampling in SPORT planning. Our BEVD guided SPORT treatment schemes improve the dose sparing to femoral heads in the prostate and brainstem, parotid glands and oral cavity in the two HN cases, where the mean dose reduction of those organs ranges from 0.5 to 2.5 Gy. Also, it increases the conformation number assessing the dose conformity to the target from 0.84, 0.75 and 0.74 to 0.86, 0.79 and 0.80 in the prostate and two HN cases, while preserving the delivery efficiency, relative to conventional single-arc VMAT plans.

[1]  A Pugachev,et al.  Computer-assisted selection of coplanar beam orientations in intensity-modulated radiation therapy. , 2001, Physics in medicine and biology.

[2]  Uwe Oelfke,et al.  Acceleration of intensity-modulated radiotherapy dose calculation by importance sampling of the calculation matrices. , 2002, Medical physics.

[3]  Steve B. Jiang,et al.  A new column-generation-based algorithm for VMAT treatment plan optimization , 2012, Physics in medicine and biology.

[4]  Radhe Mohan,et al.  Algorithm and performance of a clinical IMRT beam-angle optimization system. , 2003, Physics in medicine and biology.

[5]  I. Kawrakow Improved modeling of multiple scattering in the Voxel Monte Carlo model. , 1997, Medical physics.

[6]  M Earl,et al.  Inverse planning for intensity-modulated arc therapy using direct aperture optimization , 2003, Physics in medicine and biology.

[7]  D M Shepard,et al.  Direct aperture optimization: a turnkey solution for step-and-shoot IMRT. , 2002, Medical physics.

[8]  Lei Xing,et al.  Using total-variation regularization for intensity modulated radiation therapy inverse planning with field-specific numbers of segments , 2008, Physics in medicine and biology.

[9]  Benedick A Fraass,et al.  FusionArc optimization: a hybrid volumetric modulated arc therapy (VMAT) and intensity modulated radiation therapy (IMRT) planning strategy. , 2013, Medical physics.

[10]  A. Tarakanova,et al.  Molecular modeling of protein materials: case study of elastin , 2013 .

[11]  Tae-Suk Suh,et al.  Inverse planning for IMRT with nonuniform beam profiles using total-variation regularization (TVR). , 2011, Medical physics.

[12]  Karl Otto,et al.  Volumetric modulated arc therapy: IMRT in a single gantry arc. , 2007, Medical physics.

[13]  Lei Xing,et al.  An adaptive planning strategy for station parameter optimized radiation therapy (SPORT): Segmentally boosted VMAT. , 2013, Medical physics.

[14]  Tae-Suk Suh,et al.  Beam's-eye-view Dosimetrics-guided inverse planning for aperture-modulated arc therapy. , 2009, International journal of radiation oncology, biology, physics.

[15]  R. Garcia,et al.  Evaluation dosimétrique d'une radiothérapie conformationnelle: le facteur de conformation , 2000 .

[16]  Emmanuel J. Candès,et al.  Templates for convex cone problems with applications to sparse signal recovery , 2010, Math. Program. Comput..

[17]  Lei Xing,et al.  Point/counterpoint. DASSIM-RT is likely to become the method of choice over conventional IMRT and VMAT for delivery of highly conformal radiotherapy. , 2013, Medical physics.

[18]  Joseph O Deasy,et al.  CERR: a computational environment for radiotherapy research. , 2003, Medical physics.

[19]  T. Bortfeld,et al.  Optimization of beam orientations in radiation therapy: some theoretical considerations. , 1993, Physics in medicine and biology.

[20]  Y. Li,et al.  Automatic beam angle selection in IMRT planning using genetic algorithm. , 2004, Physics in medicine and biology.

[21]  M. Goitein,et al.  Multi-dimensional treatment planning: II. Beam's eye-view, back projection, and projection through CT sections. , 1983, International journal of radiation oncology, biology, physics.

[22]  Stephen P. Boyd,et al.  Enhancing Sparsity by Reweighted ℓ1 Minimization , 2007, 0711.1612.

[23]  James L Robar,et al.  HybridArc: a novel radiation therapy technique combining optimized dynamic arcs and intensity modulation. , 2012, Medical dosimetry : official journal of the American Association of Medical Dosimetrists.

[24]  L. Xing,et al.  Pseudo beam's-eye-view as applied to beam orientation selection in intensity-modulated radiation therapy. , 2001, International journal of radiation oncology, biology, physics.

[25]  M. Moerland,et al.  A conformation number to quantify the degree of conformality in brachytherapy and external beam irradiation: application to the prostate. , 1997, International journal of radiation oncology, biology, physics.

[26]  C G Rowbottom,et al.  Constrained customization of non-coplanar beam orientations in radiotherapy of brain tumours. , 1999, Physics in medicine and biology.

[27]  Andrew Jackson,et al.  Volumetric modulated arc therapy: planning and evaluation for prostate cancer cases. , 2010, International journal of radiation oncology, biology, physics.

[28]  L. Xing,et al.  Incorporating prior knowledge into beam orientation optimization in IMRT. , 2002, International journal of radiation oncology, biology, physics.

[29]  Lei Xing,et al.  Improving IMRT delivery efficiency with reweighted L1-minimization for inverse planning. , 2013, Medical physics.

[30]  G A Ezzell,et al.  Genetic and geometric optimization of three-dimensional radiation therapy treatment planning. , 1996, Medical physics.

[31]  K. Burnham,et al.  Optimization of beam orientation in radiotherapy using planar geometry. , 1998, Physics in medicine and biology.

[32]  Tae-Suk Suh,et al.  Efficient IMRT inverse planning with a new L1-solver: template for first-order conic solver. , 2012, Physics in medicine and biology.

[33]  Steve B. Jiang,et al.  Beam orientation optimization for intensity modulated radiation therapy using adaptive l2,1-minimization , 2011, Physics in medicine and biology.

[34]  Lei Xing,et al.  Inverse planning in the age of digital LINACs: station parameter optimized radiation therapy (SPORT) , 2014 .