Table 1.
Treatment plan parameters–Vestibular Schwannoma.
Fig 1.
Calculation matrix, number of the isocenters and dose distribution.
(A) For each target volume defined, a calculation matrix is created, which automatically encloses the volume to adjust the position and the grid size to enclose the selected target volume. (B) multiples isocenters are used, especially when the shape of target volume is irregular. (C) dose distribution of plan (yellow line is prescription isodose line = 12 Gy).
Fig 2.
Sphericity degree of target volume.
Target volume dimensions to calculate the sphericity (φ). Mathematics equation is defined by Wadell [13].
Fig 3.
Diagram to illustrate coverage, selectivity, gradient index and PIVradius and equations.
Fig 4.
Plan with equivalent spherical volume.
(A) Contribution parameters to define using algorithm TMR 10. (B) Calculation of equivalent spherical volume for target. (C) equivalent spherical target and phantom.
Fig 5.
(A) Dose-volume histogram for Tumor. (B) Dose-volume histogram for Matrix (absolute dose). (C) Dose-volume histogram (relative dose). (D) Table volume analysis. Tools on LGP to obtain the Paddick conformity index (CIPaddick).
Fig 6.
Quantitative analysis of ratio IV/TV.
(A) Graph presenting the dose distribution against the ratio between isodose volume (IV) and target volume (TV) considering (φ) = 0,66 for different shot densities (SD). (B) Graph presenting the dose distribution against the ratio between isodose volume (IV) and target volume (TV) considering (φ) = 0,77 for different shot densities (SD).
Fig 7.
Quantitative analysis of targets and their respective sphericity degree.
Fig 8.
Selectivity (S) versus sphericity degree (φ).
Fig 9.
Gradient index (GI) versus sphericity degree (φ).
Fig 10.
Conformity index (CI) versus sphericity degree (φ).
Fig 11.
Mean dose (MD) versus sphericity degree (φ).
Fig 12.
Dose distribution of a reference plan.
The target volume is spherical (Yellow Line = Prescription Isodose) with a diameter of 8 mm: (a) Axial plane, (b) Coronal plane and e (c) Sagittal plane.
Fig 13.
Quantitative analysis of relative isodoses volumes for different spherical target volume.
Fig 14.
Dose distribution considering range of sphereicity degree.
(A) Sphericity degree (φ: 0,50–0,58). (B) Sphericity degree (φ: 0,61–0,66). (C) Sphericity degree (φ: 0,67–0,69). (D) Sphericity degree (φ: 0,70–0,74). (E) Sphericity degree (φ: 0,75–0,77). (F) Sphericity degree (φ: 0,78–0,91).