TABLE 3.
Dosimetric comparison for organs at risk for VMAT and IMRT plans
| Study (reference) | Parotid glands average D mean (Gy) | Spinal cord (Gy) | Brainstem (Gy) | |||
|---|---|---|---|---|---|---|
| VMAT | IMRT | VMAT | IMRT | VMAT | IMRT | |
| VMAT vs IMRT for oropharynx, larynx hypopharynx, 29 patients, (Vanetti, 2009) 19 | 31.3 | 35.35 | D 2% = 39.0 | D 2% = 42.8 | D 2% = 38.2 | D 2% = 24.8 |
| Single arc volumetric modulated arc therapy of head and neck cancer 25 patients (Bertelsen, 2010) 27 | 27.85 | 28.2 | D max = 44.2 | D max = 44.8 | — | — |
| VMAT and step‐and‐shoot IMRT in HNC 15 patients (Wiehle, 2011) 4 | 20.7 | 22.2 | D 2% = 36.7 | D 2% = 37.4 | — | — |
| VMAT vs TomoTherapy vs step‐and‐shoot IMRT 20 patietnts (Lu, 2011) 10 | 26.3 | 31.3 | D max = 30.5 | D max = 36.1 | D max = 48.8 | D max = 53.1 |
| VMAT vs IMRT SiB of nasopharynx 20 patients (Lee, 2011) 9 | Dose reduction of D mean by 1.22 ± 1.38 Gy from IMRT to VMAT | Dose reduction of D max by 1.34 ± 2.29 Gy from IMRT to VMAT | Dose reduction of D max by 1.58 ± 1.75 Gy from IMRT to VMAT | |||
| Smartarc‐based VMAT vs IMRT vs tomotherapy 8 patients (Clemente, 2011) 11 | 30.85 | 31.1 | D 0.1cc = 35.9 | D 0.1cc 35.8 | D 0.1cc = 44.3 | D 0.1cc = 44.5 |
| A comparison of several modulated RT techniques 10 patients (Stieler, 2011) 12 | 14.9 | 14 | D max = 42.6 | D max = 41.2 | D max = 47.8 | D max = 44.85 |
| Clinical experience transitioning from IMRT to VMAT in HNC 20 patients (Studenski, 2012) 15 | 26.6 | 29.3 | D max = 44 | D max = 43 | D max = 48 | D max = 51 |
| VMAT vs conventional IMRT 20 patients (Fung‐Kee‐Fung, 2012) 2 | 46.6 | 47.05 | D mean = 20.9 | D mean = 20.4 | D mean = 14.3 | D mean = 15.3 |
| Static and rotational IMRT for HNC 18 patients (Broggi, 2014) 13 | 34.8 (Electa)/36.6 (Varian) | 32 Gy | D max = 40.8(Electa) D max = 38 (Varian) | D max = 40.4 | D max = 47.5 (Electa) D max = 46 (Varian) | D max = 48 |
| Equally spaced beam, beam angle optimization, and VMAT in HNC 119 patients (Leung, 2019) 17 | 28.22 | 27.75 | D 2% = 41.65 | D 2% = 41.3 | D 2% = 45.81 | D 2% = 46.05 |
| VMAT, IMRT and helical tomotherapy for the ESCALOX‐trial pre‐study 6 patients (Pigorsch, 2020) 7 | 29.55 | 29.65 | D max = 50.5 | D max = 51.9 | D max = 27.4 | D max = 29.07 |
Abbreviations: HNC, head and neck cancer; IMRT, intensity modulated radiation therapy; RT, radiotherapy; VMAT, volumetric modulated arc therapy.