PMID- 35504799
OWN - NLM
STAT- MEDLINE
DCOM- 20221003
LR  - 20230225
IS  - 1876-4436 (Electronic)
IS  - 0939-3889 (Print)
IS  - 0939-3889 (Linking)
VI  - 32
IP  - 3
DP  - 2022 Aug
TI  - Single-isocenter stereotactic radiosurgery for multiple brain metastases: Impact 
      of patient misalignments on target coverage in non-coplanar treatments.
PG  - 296-311
LID - S0939-3889(22)00033-2 [pii]
LID - 10.1016/j.zemedi.2022.02.005 [doi]
AB  - Frameless single-isocenter non-coplanar stereotactic radiosurgery (SRS) for 
      patients with multiple brain metastases is a treatment at high geometrical 
      complexity. The goal of this study is to analyze the dosimetric impact of 
      non-coplanar image guidance with stereoscopic X-ray imaging. Such an analysis is 
      meant to provide insights on the adequacy of safety margins, and to evaluate the 
      benefit of imaging at non-coplanar configurations. The ExacTrac(R) (ET) system 
      (Brainlab AG, Munich, Germany) was used for stereoscopic X-ray imaging in 
      frameless single-isocenter non-coplanar SRS for multiple brain metastases. 
      Sub-millimeter precision was found for the ET-based pre-treatment setup, whereas 
      a degradation was noted for non-coplanar treatment angles. Misalignments without 
      intra-fractional positioning corrections were reconstructed in 6 degrees of 
      freedom (DoF) to resemble the situation without non-coplanar image guidance. Dose 
      recalculation in 20 SRS patients with applied positioning corrections did not 
      reveal any significant differences in D(98%) for 75 planning target volumes 
      (PTVs) and gross tumor volumes (GTVs). For recalculation without applied 
      positioning corrections, significant differences (p<0.05) were reported in D(98%) 
      for both PTVs and GTVs, with stronger effects for small PTV volumes. A worst-case 
      analysis at increasing translational and rotational misalignment revealed that 
      dosimetric changes are a complex function of the combination thereof. This study 
      highlighted the important role of positioning correction with ET at non-coplanar 
      configurations in frameless single-isocenter non-coplanar SRS for patients with 
      multiple brain metastases. Uncorrected patient misalignments at non-coplanar 
      couch angles were linked to a significant loss of PTV coverage, with effects 
      varying according to the combination of single DoF and PTV geometrical 
      properties.
CI  - Copyright (c) 2022. Published by Elsevier GmbH.
FAU - Eder, Michael Martin
AU  - Eder MM
AD  - Department of Radiation Oncology, University Hospital, LMU Munich, Munich, 
      Germany; Department of Medical Physics, Ludwig-Maximilians University, Garching, 
      Germany. Electronic address: mi.eder@protonmail.com.
FAU - Reiner, Michael
AU  - Reiner M
AD  - Department of Radiation Oncology, University Hospital, LMU Munich, Munich, 
      Germany. Electronic address: michael.reiner@med.uni-muenchen.de.
FAU - Heinz, Christian
AU  - Heinz C
AD  - Department of Radiation Oncology, University Hospital, LMU Munich, Munich, 
      Germany. Electronic address: christian.heinz@med.uni-muenchen.de.
FAU - Garny, Sylvia
AU  - Garny S
AD  - Department of Radiation Oncology, University Hospital, LMU Munich, Munich, 
      Germany. Electronic address: sylvia.garny@med.uni-muenchen.de.
FAU - Freislederer, Philipp
AU  - Freislederer P
AD  - Department of Radiation Oncology, University Hospital, LMU Munich, Munich, 
      Germany. Electronic address: philipp.freislederer@med.uni-muenchen.de.
FAU - Landry, Guillaume
AU  - Landry G
AD  - Department of Radiation Oncology, University Hospital, LMU Munich, Munich, 
      Germany; Department of Medical Physics, Ludwig-Maximilians University, Garching, 
      Germany. Electronic address: guillaume.landry@med.uni-muenchen.de.
FAU - Niyazi, Maximilian
AU  - Niyazi M
AD  - Department of Radiation Oncology, University Hospital, LMU Munich, Munich, 
      Germany; German Cancer Consortium (DKTK), Partner Site Munich, Munich, Germany. 
      Electronic address: maximilian.niyazi@med.uni-muenchen.de.
FAU - Belka, Claus
AU  - Belka C
AD  - Department of Radiation Oncology, University Hospital, LMU Munich, Munich, 
      Germany; German Cancer Consortium (DKTK), Partner Site Munich, Munich, Germany. 
      Electronic address: claus.belka@med.uni-muenchen.de.
FAU - Riboldi, Marco
AU  - Riboldi M
AD  - Department of Radiation Oncology, University Hospital, LMU Munich, Munich, 
      Germany. Electronic address: marco.riboldi@physik.uni-muenchen.de.
LA  - eng
PT  - Journal Article
DEP - 20220430
PL  - Germany
TA  - Z Med Phys
JT  - Zeitschrift fur medizinische Physik
JID - 100886455
SB  - IM
MH  - *Brain Neoplasms/diagnostic imaging/radiotherapy/secondary
MH  - Germany
MH  - Humans
MH  - Radiometry
MH  - *Radiosurgery/methods
MH  - Radiotherapy Dosage
MH  - Radiotherapy Planning, Computer-Assisted/methods
PMC - PMC9948862
OTO - NOTNLM
OT  - Multiple brain metastases
OT  - Non-coplanar
OT  - Patient positioning
OT  - Single-isocenter
OT  - Stereoscopic X-ray imaging
OT  - Stereotactic radiosurgery
COIS- The Department of Radiation Oncology of the University Hospital of LMU Munich 
      holds research agreements with Brainlab, Elekta and ViewRay.
EDAT- 2022/05/04 06:00
MHDA- 2022/10/04 06:00
PMCR- 2022/04/30
CRDT- 2022/05/03 22:05
PHST- 2021/09/06 00:00 [received]
PHST- 2022/02/10 00:00 [revised]
PHST- 2022/02/14 00:00 [accepted]
PHST- 2022/05/04 06:00 [pubmed]
PHST- 2022/10/04 06:00 [medline]
PHST- 2022/05/03 22:05 [entrez]
PHST- 2022/04/30 00:00 [pmc-release]
AID - S0939-3889(22)00033-2 [pii]
AID - 10.1016/j.zemedi.2022.02.005 [doi]
PST - ppublish
SO  - Z Med Phys. 2022 Aug;32(3):296-311. doi: 10.1016/j.zemedi.2022.02.005. Epub 2022 
      Apr 30.