Document Detail

A new method of lower extremity immobilization in radiotherapy.
Jump to Full Text
MedLine Citation:
PMID:  22376892     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
We developed a new method for immobilization of the fix lower extremities by using a thermoplastic mask, a carbon fiber base plate, a customized headrest, and an adjustable angle holder. The lower extremities of 11 patients with lower extremity tumors were immobilized by this method. CT simulation was performed for each patient. For all 11 patients, the device fit was suitable and comfortable and had good reproducibility, which was proven in daily radiotherapy.
Authors:
Xuhai Zheng; Tangzhi Dai; Xiaochuan Shu; Yuanxue Pu; Gang Feng; Xuesong Li; Dongbiao Liao; Xiaobo Du
Publication Detail:
Type:  Journal Article     Date:  2012-02-29
Journal Detail:
Title:  Radiation oncology (London, England)     Volume:  7     ISSN:  1748-717X     ISO Abbreviation:  Radiat Oncol     Publication Date:  2012  
Date Detail:
Created Date:  2012-03-14     Completed Date:  2012-06-01     Revised Date:  2013-06-26    
Medline Journal Info:
Nlm Unique ID:  101265111     Medline TA:  Radiat Oncol     Country:  England    
Other Details:
Languages:  eng     Pagination:  27     Citation Subset:  IM    
Affiliation:
Department of Oncology, Mian Yang Central Hospital, Sichuan, People's Republic of China.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Equipment Design
Humans
Immobilization / methods*
Lower Extremity / pathology*,  radiation effects*
Neoplasms / radiotherapy*
Prognosis
Radiotherapy, Intensity-Modulated*
Comments/Corrections

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Full Text
Journal Information
Journal ID (nlm-ta): Radiat Oncol
ISSN: 1748-717X
Publisher: BioMed Central
Article Information
Download PDF
Copyright ©2012 Zheng et al; licensee BioMed Central Ltd.
open-access:
Received Day: 24 Month: 10 Year: 2011
Accepted Day: 29 Month: 2 Year: 2012
collection publication date: Year: 2012
Electronic publication date: Day: 29 Month: 2 Year: 2012
Volume: 7First Page: 27 Last Page: 27
ID: 3305509
Publisher Id: 1748-717X-7-27
PubMed Id: 22376892
DOI: 10.1186/1748-717X-7-27

A new method of lower extremity immobilization in radiotherapy
Xuhai Zheng1 Email: haixuzheng@163.com
Tangzhi Dai1 Email: daitangzhi@tom.com
Xiaochuan Shu1 Email: daitangzhi@tom.com
Yuanxue Pu1 Email: daitangzhi@tom.com
Gang Feng1 Email: fenggangmych@yahoo.com.cn
Xuesong Li1 Email: liao_db2007@sina.com
Dongbiao Liao1 Email: liao_db2007@sina.com
Xiaobo Du12 Email: duxiaobo2005@126.com
1Department of Oncology, Mian Yang Central Hospital, Sichuan, People's Republic of China
2Department of Oncology, MianYang Central Hospital, Sichuan 621000, People's Republic of China

Background

Many tumors occur in the lower extremities, such as soft tissue sarcomas, bone sarcomas, and benign diseases [1-3]. Most patients with lower extremity tumors opt for radiotherapy because, compared to radical surgery, because multimodal treatments combining conservative surgery and radiation therapy achieves maximize long-term extremity function with excellent local control rates and minimal morbidity [4-7]. With the development of conformal radiotherapy, particularly the application of intensity-modulated radiotherapy, practitioners require new lower extremity immobilization methods that provide good reproducibility. No standard method has been established for lower extremity immobilization; most methods involve the use of alpha cradles, ankle casts, customized immobilization devices, or negative pressure vacuum air cushions [8,9]. We have developed a new method for immobilizing lower extremities with improved reproducibility and patient comfort.


Methods

The Hospital Medical Research Ethics Committee approved our research in accordance with the laws and regulations in China and all the patients gave oral and written informed consent before the start of the study.

Our device includes a thermoplastic mask (Shanghai gray prescribed medical technology Co., LTD, China), a carbon fiber base plate (MedTec,USA), a customized headrest (MedTec,USA), and an adjustable angle holder (MedTec,USA). The thermoplastic mask and adjustable angle holder were remolded before use.

We cut the U-shaped thermoplastic mask (Figure 1A and 1B), removed the rigid plastic on the top, and used the remainder of the mask. We reconstructed the adjustable angle holder by detaching the carbon fiber base plate at the bottom of the holder after removing the 4 screws at the bottom, reversing the position of the plate; and fixing it again (Figure 2A, B, C and 2D). Two screws present on each side of the mask could be manipulated to change the angle for adaptation to the varying leg-bend angles. We fixed the reassembled holder to the carbon fiber base plate and placed a suitable customized headrest on the holder. Finally, we immobilized one lower extremity with the remolded thermoplastic It is important to note that only 1 leg was immobilized while the other leg was bent (Figure 3A, B and 3C).

The lower extremities of 11 patients with lower extremity tumors were immobilized by this system. CT (General Electric Company, USA) simulation was performed for each patient. For each patient, we created a plan with the Pinnacle plan system (Philips, Holland) and performed X-ray in the anterior-posterior (AP) and lateral views every weekly (Figure 3D).


Results and discussion

The device fit for all 11 patients was suitable and comfortable, which was proven in daily radiotherapy. The mean displacement of the isocenter was 3.3 mm (from 0.4 to 6 mm) in the superior-inferior direction 2.1 mm (from 0.5 to 4 mm) in the AP direction and 1.6 mm (from 0.4 to 3 mm) in the left-right direction. The leg rotation around the isocenter was also determined and found to be negligible.

Radiotherapy plays an essential role in the treatment of lower extremity tumors [4-7,10]. In radiation methods for lower extremity tumors, Intensity-modulated radiotherapy is reported to have better target coverage than other radiation methods used for lower extremity tumors and it significantly decrease the dose to the organs-at-risk [9,11]. Intensity-modulated radiotherapy requires better reproducibility, but the lower extremities of patients with lower extremity tumors are difficult to immobilize, because of the tumor or surgical effects. In radiotherapy, immobilization of the lower extremity is achieved using alpha-cradle, ankle casts, customized immobilization devices, or negative pressure vacuum air cushions [8-10]. We developed a new method for immobilizing the lower leg by using existing materials and devices. With this method, the patients were comfortable and the reproducibility was high. First, the immobilized lower extremity could not move or turn easily, which yielded higher reproducibility. Second, some patients who were surgically treated prior to radiotherapy could not easily straighten their legs, and therefore, they found the adjustable fixation more comfortable. Third, only 1 leg was immobilized while the other leg was bent, making it easier to design treatment plans.

In conclusion, we have developed a new method for immobilizing the lower extremities for radiotherapy.


Competing interests

The authors declare that they have no competing interests.


Authors' contributions

XB Du undertook the conception and revision of the manuscript. XH Zheng and TZ Dai designed this study and drafted the manuscript. XC Shu and YX Pu carried out the immobilization procedure on the patients and collected the data. G Feng, XS Li and DB Liao performed data analysis. All authors read and approved the final manuscript.


References
Cormier JN,Pollock RE,Soft tissue sarcomasCA Cancer J ClinYear: 2004549410910.3322/canjclin.54.2.9415061599
Cotterill SJ,Ahrens S,Paulussen M,et al. Prognostic factors in Ewing's tumor of bone: analysis of 975 patients from the European Intergroup Cooperative Ewing's Sarcoma Study groupJ Clin OncolYear: 2000183108311410963639
Gurney JG,Swensen AR,Bulterys M,SEER Pediatric Monograph Available at: http://seer.cancer. gov/publications/childhood/bone.pdf. Accessed.
O'Sullivan B,Davis A,Turcotte R,et al. Five-year results of a randomized phase III trial of pre-operative vs post-operative radiotherapy in extremity soft tissue sarcomaJ Clin Oncol (Meeting Abstracts)Year: 2004229007
Yang JC,Chang AE,Baker AR,et al. Randomized prospective study of the benefit of adjuvant radiation therapy in the treatment of soft tissue sarcomas of the extremityJ Clin OncolYear: 1998161972039440743
Wilson AN,Davis A,Bell RS,et al. Local control of soft tissue sarcoma of the extremity: the experience of a multidisciplinary sarcoma group with definitive surgery and radiotherapyEur J CancerYear: 199430A746751
Dunst J,Jurgens H,Sauer R,et al. Radiation therapy in Ewing's sarcoma: an update of the CESS 86 trialInt J Radiat Oncol Biol PhysYear: 19953291993010.1016/0360-3016(95)00016-R7607966
Halperin Edward C,Perez Carlos A,Brady Luther W,Perez and Brady's Principles and Practice of Radiation OncologyYear: 20085Lippincott Williams & Wilkins181622018631
Stewart AJ,Lee YK,Saran FH,Comparison of conventional radiotherapy and intensity-modulated radiotherapy for post-operative radiotherapy for primary extremity soft tissue sarcomaRadiother OncolYear: 20099312513010.1016/j.radonc.2009.06.01019604591
Davis A,O'Sullivan B,Bell R,et al. Function and health status outcomes in a randomized trial comparing preoperative and postoperative radiotherapy in extremity soft tissue sarcomaJ Clin OncolYear: 2002204472447710.1200/JCO.2002.03.08412431971
Hong L,Alektiar KM,Hunt M,Venkatraman E,Leibel SA,Intensity-modulated radiotherapy for soft tissue sarcoma of the thighInt J Radiat Oncol Biol PhysYear: 20045975275910.1016/j.ijrobp.2003.11.03715183478

Figures

[Figure ID: F1]
Figure 1 

Ready thermoplastic mask. (A) The original thermoplastic mask for the head. (B) The mask with the rigid plastic on the top cut by us.



[Figure ID: F2]
Figure 2 

Ready adjustable angle holder reconstructed by us. (A) The adjustable angle holder. (B) The carbon fiber base plate at the bottom of the holder was detached by removing the 4 screws on the bottom. (C) The carbon fiber base plate was reversed. (D) The adjustable angle holder was reassembled.



[Figure ID: F3]
Figure 3 

Immobilized lower extremity. (A) The device displayed here is a combination of the following 3 parts: the carbon base plate at the bottom, the reconstructed adjustable angle holder in the middle, and a customized headrest at the top. (B) An example of thigh fixation. (C) An example of crus fixation. (D) An image of a part of our plan system.



Article Categories:
  • Methodology

Keywords: Lower extremity, Immobilization, Radiotherapy.

Previous Document:  Rest versus exercise as treatment for patients with low back pain and Modic changes. A randomized co...
Next Document:  Evaluation of a combined triple method to detect causative HPV in oral and oropharyngeal squamous ce...