Matches in SemOpenAlex for { <https://semopenalex.org/work/W3015123724> ?p ?o ?g. }
- W3015123724 endingPage "287" @default.
- W3015123724 startingPage "275" @default.
- W3015123724 abstract "Besides conventional single fraction stereotactic radiosurgery (SRS), the newer Gamma Knife® (Elekta Instruments, AB, Sweden) (GK) models, Perfexion™ and Icon™, also allow the option of hypofractionated SRS, to widen the treatment range, reduce toxicity and provide flexibility. With fractionation, set-up uncertainties are introduced to the treatment. The question of what margin is required to cover set-up uncertainties arises. In this work, the characteristics of positional uncertainties and margins required to ensure coverage are evaluated. An alternative strategy on how to deal with set-up errors is suggested.Five large single metastases have been considered to simulate the dosimetric effects of set-up uncertainties. Since random error would not create a representative average for three or five fractions a worst case scenario with maximal displacement in different directions has been evaluated. Displacements of 0.5, 1.0, 2.0, 3.0 and 4.0 mm have been considered. Three fraction treatments were simulated with displacements in X, Y and Z directions (3FXYZ) and in ±X and Z directions (3F±XZ). For five fractions, the displacements were ±X, ±Y and Z (5F±X±YZ) resulting in the largest possible spread of the dose distribution. Plans were evaluated by considering the volumes of the reference dose and the 50% isodose, as well as the Paddick conformity index (PCI), the gradient index (GI) and coverage. Based on the change in coverage a margin was evaluated that would have prevented underdosage of the target.Two fractions displaced up to ±2 mm in opposing directions almost cancel each other out. Minimum dose was reduced by 10% (3FXYZ), 4% (3F±XZ) and 1% (5F±X±YZ). The main contribution to the underdosage was due to the small systematic error (shift) included in the simulated displacements.The margin required to keep the coverage of the target comparable with the original plan would be 0.5 mm for the 3FXYZ plan, 0.2 mm for the 3F±XZ plan and 0.0 mm for the 5F±X±YZ for a set-up error of 2 mm.For fractionated GK treatment of large brain metastases prescribing to the 50% isodose minimizes the effect of random error.For conventional single fraction SRS, the effect of positional uncertainty is always systematic. However, for fractionated treatments, positional uncertainty can be separated into random and systematic components, where random displacements in opposing directions at least partially cancel each other out and thus reduce the overall systematic effect (i.e. from the residual systematic uncertainty). Therefore fractionated schemes with more fractions are preferable from the point of view of accounting for positional uncertainties. If the random and systematic uncertainties can be assessed and determined separately by imaging, then the residual systematic value can be corrected for the remaining fractions." @default.
- W3015123724 created "2020-04-10" @default.
- W3015123724 creator A5011571875 @default.
- W3015123724 creator A5046598190 @default.
- W3015123724 creator A5064434962 @default.
- W3015123724 creator A5083421034 @default.
- W3015123724 date "2017-01-01" @default.
- W3015123724 modified "2023-09-23" @default.
- W3015123724 title "Quantifying the effects of positional uncertainties and estimating margins for Gamma-Knife® fractionated radiosurgery of large brain metastases." @default.
- W3015123724 cites W1481445941 @default.
- W3015123724 cites W1702197803 @default.
- W3015123724 cites W1963648830 @default.
- W3015123724 cites W1965780473 @default.
- W3015123724 cites W1981034230 @default.
- W3015123724 cites W1989416923 @default.
- W3015123724 cites W1994374489 @default.
- W3015123724 cites W2002911053 @default.
- W3015123724 cites W2026709105 @default.
- W3015123724 cites W2032700496 @default.
- W3015123724 cites W2035239932 @default.
- W3015123724 cites W2043650924 @default.
- W3015123724 cites W2046701188 @default.
- W3015123724 cites W2056775578 @default.
- W3015123724 cites W2064292478 @default.
- W3015123724 cites W2071098381 @default.
- W3015123724 cites W2074010027 @default.
- W3015123724 cites W2078206402 @default.
- W3015123724 cites W2083128109 @default.
- W3015123724 cites W2089685650 @default.
- W3015123724 cites W2096973175 @default.
- W3015123724 cites W2111653524 @default.
- W3015123724 cites W2126680055 @default.
- W3015123724 cites W2139792111 @default.
- W3015123724 cites W2142064307 @default.
- W3015123724 cites W2143843774 @default.
- W3015123724 cites W2147563445 @default.
- W3015123724 cites W2149710876 @default.
- W3015123724 cites W2976889717 @default.
- W3015123724 cites W4236513775 @default.
- W3015123724 cites W1927575959 @default.
- W3015123724 hasPubMedCentralId "https://www.ncbi.nlm.nih.gov/pmc/articles/5658823" @default.
- W3015123724 hasPubMedId "https://pubmed.ncbi.nlm.nih.gov/29296452" @default.
- W3015123724 hasPublicationYear "2017" @default.
- W3015123724 type Work @default.
- W3015123724 sameAs 3015123724 @default.
- W3015123724 citedByCount "5" @default.
- W3015123724 countsByYear W30151237242018 @default.
- W3015123724 countsByYear W30151237242019 @default.
- W3015123724 countsByYear W30151237242022 @default.
- W3015123724 crossrefType "journal-article" @default.
- W3015123724 hasAuthorship W3015123724A5011571875 @default.
- W3015123724 hasAuthorship W3015123724A5046598190 @default.
- W3015123724 hasAuthorship W3015123724A5064434962 @default.
- W3015123724 hasAuthorship W3015123724A5083421034 @default.
- W3015123724 hasConcept C119857082 @default.
- W3015123724 hasConcept C126838900 @default.
- W3015123724 hasConcept C149629883 @default.
- W3015123724 hasConcept C159985019 @default.
- W3015123724 hasConcept C178790620 @default.
- W3015123724 hasConcept C185592680 @default.
- W3015123724 hasConcept C192562407 @default.
- W3015123724 hasConcept C204323151 @default.
- W3015123724 hasConcept C2780387249 @default.
- W3015123724 hasConcept C2989005 @default.
- W3015123724 hasConcept C2994042627 @default.
- W3015123724 hasConcept C33923547 @default.
- W3015123724 hasConcept C41008148 @default.
- W3015123724 hasConcept C509974204 @default.
- W3015123724 hasConcept C71924100 @default.
- W3015123724 hasConcept C774472 @default.
- W3015123724 hasConceptScore W3015123724C119857082 @default.
- W3015123724 hasConceptScore W3015123724C126838900 @default.
- W3015123724 hasConceptScore W3015123724C149629883 @default.
- W3015123724 hasConceptScore W3015123724C159985019 @default.
- W3015123724 hasConceptScore W3015123724C178790620 @default.
- W3015123724 hasConceptScore W3015123724C185592680 @default.
- W3015123724 hasConceptScore W3015123724C192562407 @default.
- W3015123724 hasConceptScore W3015123724C204323151 @default.
- W3015123724 hasConceptScore W3015123724C2780387249 @default.
- W3015123724 hasConceptScore W3015123724C2989005 @default.
- W3015123724 hasConceptScore W3015123724C2994042627 @default.
- W3015123724 hasConceptScore W3015123724C33923547 @default.
- W3015123724 hasConceptScore W3015123724C41008148 @default.
- W3015123724 hasConceptScore W3015123724C509974204 @default.
- W3015123724 hasConceptScore W3015123724C71924100 @default.
- W3015123724 hasConceptScore W3015123724C774472 @default.
- W3015123724 hasIssue "4" @default.
- W3015123724 hasLocation W30151237241 @default.
- W3015123724 hasOpenAccess W3015123724 @default.
- W3015123724 hasPrimaryLocation W30151237241 @default.
- W3015123724 hasRelatedWork W1149154872 @default.
- W3015123724 hasRelatedWork W1168725967 @default.
- W3015123724 hasRelatedWork W1975398742 @default.
- W3015123724 hasRelatedWork W1976550197 @default.
- W3015123724 hasRelatedWork W1992111185 @default.
- W3015123724 hasRelatedWork W2003852277 @default.
- W3015123724 hasRelatedWork W2016452354 @default.
- W3015123724 hasRelatedWork W2035729249 @default.