TH‐C‐T‐6C‐06: Feasibility of Dynamic Feathering for Field Junctions

H. Hesami, M. Bastasch, L. ku, F. Hager, G. Zhang, S. Shaddock, D. Rosenthal, K. Forster

Research output: Contribution to journalArticle

Abstract

Purpose: Patients are not perfectly immobilized and there is always some movement during treatments. Field junctions are typically shifted several times during the course of treatment to ensure that the effects of imperfect junctions and patient motion are minimized. We have evaluated a dynamic feathering scheme that reduces daily hot and cold spots at field junctions, and may eliminate the need for junction shifting in the future. Method and Materials: Five craniospinal patients were planned using both conventional and dynamic feathering techniques. Using conventional feathering, the inferior border of the cranial fields were moved after each set of 5 fractions by increasing the inferior borders by 1 cm and closing the spine field by 1 cm. In the second plan we simulated an automated feathering technique in which the cranial fields opened dynamically and the spine field closed at the same rate, thus using one set of beams for the entire treatment. Patient motion of up to 5 mm was simulated and the dose distributions were analyzed. Film verification was performed to verify dose distributions. Results: Comparison between the conventional and dynamic feathering plans show a slight advantage to automatic feathering. However, in conventional cases where 5 mm overlap is simulated, hotspots of 51%–63% were observed, but these were reduced to 33% using dynamic plans. Besides, only 44% of the prescribed dose covered the spinal cord at the junction for the conventional plan while 89% for the dynamic plan if 5 mm of gap was simulated. Conclusion: Dynamic feathering yields better dose homogeneity and reduces the effects of overlapping or over‐gapping field matches on a daily basis. This technique requires only a single plan, which reduces the workload on the physicists, dosimetrists, and therapists. In our continuation of this work we are investigating automated dynamic feathering on our linac.

Original languageEnglish (US)
Pages (from-to)2163
Number of pages1
JournalMedical Physics
Volume32
Issue number6
DOIs
StatePublished - 2005

Fingerprint

Spine
Workload
Spinal Cord
Therapeutics

ASJC Scopus subject areas

  • Biophysics
  • Radiology Nuclear Medicine and imaging

Cite this

Hesami, H., Bastasch, M., ku, L., Hager, F., Zhang, G., Shaddock, S., ... Forster, K. (2005). TH‐C‐T‐6C‐06: Feasibility of Dynamic Feathering for Field Junctions. Medical Physics, 32(6), 2163. https://doi.org/10.1118/1.1998662

TH‐C‐T‐6C‐06 : Feasibility of Dynamic Feathering for Field Junctions. / Hesami, H.; Bastasch, M.; ku, L.; Hager, F.; Zhang, G.; Shaddock, S.; Rosenthal, D.; Forster, K.

In: Medical Physics, Vol. 32, No. 6, 2005, p. 2163.

Research output: Contribution to journalArticle

Hesami, H, Bastasch, M, ku, L, Hager, F, Zhang, G, Shaddock, S, Rosenthal, D & Forster, K 2005, 'TH‐C‐T‐6C‐06: Feasibility of Dynamic Feathering for Field Junctions', Medical Physics, vol. 32, no. 6, pp. 2163. https://doi.org/10.1118/1.1998662
Hesami H, Bastasch M, ku L, Hager F, Zhang G, Shaddock S et al. TH‐C‐T‐6C‐06: Feasibility of Dynamic Feathering for Field Junctions. Medical Physics. 2005;32(6):2163. https://doi.org/10.1118/1.1998662
Hesami, H. ; Bastasch, M. ; ku, L. ; Hager, F. ; Zhang, G. ; Shaddock, S. ; Rosenthal, D. ; Forster, K. / TH‐C‐T‐6C‐06 : Feasibility of Dynamic Feathering for Field Junctions. In: Medical Physics. 2005 ; Vol. 32, No. 6. pp. 2163.
@article{683c197a534d494f8f79536d3ebab787,
title = "TH‐C‐T‐6C‐06: Feasibility of Dynamic Feathering for Field Junctions",
abstract = "Purpose: Patients are not perfectly immobilized and there is always some movement during treatments. Field junctions are typically shifted several times during the course of treatment to ensure that the effects of imperfect junctions and patient motion are minimized. We have evaluated a dynamic feathering scheme that reduces daily hot and cold spots at field junctions, and may eliminate the need for junction shifting in the future. Method and Materials: Five craniospinal patients were planned using both conventional and dynamic feathering techniques. Using conventional feathering, the inferior border of the cranial fields were moved after each set of 5 fractions by increasing the inferior borders by 1 cm and closing the spine field by 1 cm. In the second plan we simulated an automated feathering technique in which the cranial fields opened dynamically and the spine field closed at the same rate, thus using one set of beams for the entire treatment. Patient motion of up to 5 mm was simulated and the dose distributions were analyzed. Film verification was performed to verify dose distributions. Results: Comparison between the conventional and dynamic feathering plans show a slight advantage to automatic feathering. However, in conventional cases where 5 mm overlap is simulated, hotspots of 51{\%}–63{\%} were observed, but these were reduced to 33{\%} using dynamic plans. Besides, only 44{\%} of the prescribed dose covered the spinal cord at the junction for the conventional plan while 89{\%} for the dynamic plan if 5 mm of gap was simulated. Conclusion: Dynamic feathering yields better dose homogeneity and reduces the effects of overlapping or over‐gapping field matches on a daily basis. This technique requires only a single plan, which reduces the workload on the physicists, dosimetrists, and therapists. In our continuation of this work we are investigating automated dynamic feathering on our linac.",
author = "H. Hesami and M. Bastasch and L. ku and F. Hager and G. Zhang and S. Shaddock and D. Rosenthal and K. Forster",
year = "2005",
doi = "10.1118/1.1998662",
language = "English (US)",
volume = "32",
pages = "2163",
journal = "Medical Physics",
issn = "0094-2405",
publisher = "AAPM - American Association of Physicists in Medicine",
number = "6",

}

TY - JOUR

T1 - TH‐C‐T‐6C‐06

T2 - Feasibility of Dynamic Feathering for Field Junctions

AU - Hesami, H.

AU - Bastasch, M.

AU - ku, L.

AU - Hager, F.

AU - Zhang, G.

AU - Shaddock, S.

AU - Rosenthal, D.

AU - Forster, K.

PY - 2005

Y1 - 2005

N2 - Purpose: Patients are not perfectly immobilized and there is always some movement during treatments. Field junctions are typically shifted several times during the course of treatment to ensure that the effects of imperfect junctions and patient motion are minimized. We have evaluated a dynamic feathering scheme that reduces daily hot and cold spots at field junctions, and may eliminate the need for junction shifting in the future. Method and Materials: Five craniospinal patients were planned using both conventional and dynamic feathering techniques. Using conventional feathering, the inferior border of the cranial fields were moved after each set of 5 fractions by increasing the inferior borders by 1 cm and closing the spine field by 1 cm. In the second plan we simulated an automated feathering technique in which the cranial fields opened dynamically and the spine field closed at the same rate, thus using one set of beams for the entire treatment. Patient motion of up to 5 mm was simulated and the dose distributions were analyzed. Film verification was performed to verify dose distributions. Results: Comparison between the conventional and dynamic feathering plans show a slight advantage to automatic feathering. However, in conventional cases where 5 mm overlap is simulated, hotspots of 51%–63% were observed, but these were reduced to 33% using dynamic plans. Besides, only 44% of the prescribed dose covered the spinal cord at the junction for the conventional plan while 89% for the dynamic plan if 5 mm of gap was simulated. Conclusion: Dynamic feathering yields better dose homogeneity and reduces the effects of overlapping or over‐gapping field matches on a daily basis. This technique requires only a single plan, which reduces the workload on the physicists, dosimetrists, and therapists. In our continuation of this work we are investigating automated dynamic feathering on our linac.

AB - Purpose: Patients are not perfectly immobilized and there is always some movement during treatments. Field junctions are typically shifted several times during the course of treatment to ensure that the effects of imperfect junctions and patient motion are minimized. We have evaluated a dynamic feathering scheme that reduces daily hot and cold spots at field junctions, and may eliminate the need for junction shifting in the future. Method and Materials: Five craniospinal patients were planned using both conventional and dynamic feathering techniques. Using conventional feathering, the inferior border of the cranial fields were moved after each set of 5 fractions by increasing the inferior borders by 1 cm and closing the spine field by 1 cm. In the second plan we simulated an automated feathering technique in which the cranial fields opened dynamically and the spine field closed at the same rate, thus using one set of beams for the entire treatment. Patient motion of up to 5 mm was simulated and the dose distributions were analyzed. Film verification was performed to verify dose distributions. Results: Comparison between the conventional and dynamic feathering plans show a slight advantage to automatic feathering. However, in conventional cases where 5 mm overlap is simulated, hotspots of 51%–63% were observed, but these were reduced to 33% using dynamic plans. Besides, only 44% of the prescribed dose covered the spinal cord at the junction for the conventional plan while 89% for the dynamic plan if 5 mm of gap was simulated. Conclusion: Dynamic feathering yields better dose homogeneity and reduces the effects of overlapping or over‐gapping field matches on a daily basis. This technique requires only a single plan, which reduces the workload on the physicists, dosimetrists, and therapists. In our continuation of this work we are investigating automated dynamic feathering on our linac.

UR - http://www.scopus.com/inward/record.url?scp=85024814798&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85024814798&partnerID=8YFLogxK

U2 - 10.1118/1.1998662

DO - 10.1118/1.1998662

M3 - Article

AN - SCOPUS:85024814798

VL - 32

SP - 2163

JO - Medical Physics

JF - Medical Physics

SN - 0094-2405

IS - 6

ER -