scholarly journals Reduced dose to small bowel with the prone position and a belly board versus the supine position in neoadjuvant 3D conformal radiotherapy for rectal adenocarcinoma

2016 ◽  
Vol 64 (2) ◽  
pp. 120-124 ◽  
Author(s):  
Rohen White ◽  
Farshad Foroudi ◽  
Joseph Sia ◽  
Mary Ann Marr ◽  
Daryl Lim Joon
Keyword(s):  
Small Bowel ◽  
Prone Position ◽  
Supine Position ◽  
Rectal Adenocarcinoma ◽  
Conformal Radiotherapy ◽  
Reduced Dose ◽  
3D Conformal Radiotherapy ◽  
Belly Board

scholarly journals Conventional 3D conformal radiotherapy and volumetric modulated arc therapy for cervical cancer: Comparison of clinical results with special consideration of the influence of patient- and treatment-related parameters

2021 ◽  
Author(s):  
Leif Hendrik Dröge ◽  
Franziska-Felicitas von Sivers ◽  
Markus Anton Schirmer ◽  
Hendrik Andreas Wolff
Keyword(s):  
Cervical Cancer ◽  
Small Bowel ◽  
Acute Toxicity ◽  
Volumetric Modulated Arc Therapy ◽  
Late Toxicity ◽  
Conformal Radiotherapy ◽  
Clinical Results ◽  
Special Consideration ◽  
3D Conformal Radiotherapy ◽  
Arc Therapy

Abstract Purpose Intensity-modulated radiotherapy (IMRT) for cervical cancer yields favorable results in terms of oncological outcomes, acute toxicity, and late toxicity. Limited data are available on clinical results with volumetric modulated arc therapy (VMAT). This study’s purpose is to compare outcome and toxicity with VMAT to conventional 3D conformal radiotherapy (3DCRT), giving special consideration to the influence of patient- and treatment-related parameters on side effects. Materials and methods Patients with cervical cancer stage I–IVA underwent radiotherapy alone or chemoradiotherapy using 3DCRT (n = 75) or VMAT (n = 30). Survival endpoints were overall survival, progression-free survival, and locoregional control. The National Cancer Institute Common Terminology Criteria for Adverse Events and the Late Effects of Normal Tissues criteria were used for toxicity assessment. Toxicity and patient- and treatment-related parameters were included in a multivariable model. Results There were no differences in survival rates between treatment groups. VMAT significantly reduced late small bowel toxicity (OR = 0.10, p = 0.03). Additionally, VMAT was associated with an increased risk of acute urinary toxicity (OR = 2.94, p = 0.01). A low body mass index (BMI; OR = 2.46, p = 0.03) and overall acute toxicity ≥grade 2 (OR = 4.17, p < 0.01) were associated with increased overall late toxicity. Conclusion We demonstrated significant reduction of late small bowel toxicity with VMAT treatment, an improvement in long-term morbidity is conceivable. VMAT-treated patients experienced acute urinary toxicity more frequently. Further analysis of patient- and treatment-related parameters indicates that the close monitoring of patients with low BMI and of patients who experienced relevant acute toxicity during follow-up care could improve late toxicity profiles.

Preoperative chemoradiotherapy for locally advanced rectal adenocarcinoma: A dosimetric comparison of intensity-modulated radiation therapy (IMRT) with three-dimensional conformal radiotherapy (3D-CRT).

2011 ◽  
Vol 29 (4_suppl) ◽  
pp. 615-615
Author(s):  
C. T. Tao ◽  
L. M. Scala ◽  
H. Gee ◽  
D. Lim ◽  
B. Padilla ◽  
...  
Keyword(s):  
Small Bowel ◽  
Organs At Risk ◽  
Locally Advanced ◽  
Rectal Adenocarcinoma ◽  
Conformal Radiotherapy ◽  
Preoperative Chemoradiotherapy ◽  
Dosimetric Comparison ◽  
Pelvic Malignancies ◽  
Femoral Heads ◽  
3D Crt

615 Background: Small bowel and bladder toxicities (bleeding, obstruction, perforation, and stricture) are rare but serious late complications of pelvic radiotherapy (RT) related to dose received by these organs. IMRT has been used effectively in other pelvic malignancies (prostate and gynecologic) to decrease the dose to normal tissues when compared to 3D-CRT. Few studies have examined the use of IMRT in rectal cancer to assess whether a similar dose reduction is feasible. Methods: Eight consecutively treated patients with T2/T3 and N0/N1 rectal adenocarcinoma underwent 5-FU based neoadjuvant chemo-RT using 7-field sliding-window IMRT between 2008 and 2010. Retrospectively, conventional 4-field 3D-CRT plans were generated for dosimetric comparison with IMRT treatment plans. Planning target volumes included the gross tumor, rectum, peri-rectal tissues, pre-sacral space, and common and internal iliac lymphatics. Organs at risk included small bowel (contoured as all small bowel identified on the planning CT plus a 1 cm symmetrical expansion), bladder, and femoral heads. Small bowel, bladder, and femoral head mean doses and volumes receiving 45 Gy (V45) were compared between conventional and IMRT plans, respectively. Paired Student's t-test was used for statistical analysis. Results: Mean prescription dose was 52.9 ± 3.3 Gy. Compared to 3D-CRT, IMRT plans had an 11% lower mean dose delivered to the bladder (38.2 ± 4.5 Gy vs 43.1 ± 1.9 Gy, p = 0.028) and 24% lower mean dose to the small bowel (24.0 ± 2.9 Gy vs 31.7 ± 7.7 Gy, p = 0.014). IMRT plans also had a 55% lower bladder V45 (27 ± 19% vs 61 ± 22%, p = 0.0077) and a 96% lower small bowel V45 (1 ± 0% vs 21± 20%, p = 0.021). The femoral heads received a nonsignificant higher mean dose (19.2 ± 3.9 Gy vs 16.6 ± 3.0 Gy, p = 0.069). Conclusions: Small bowel and bladder volume receiving 45 Gy and mean dose were significantly lower using IMRT compared with 3D-CRT planning. More stringent volumetric planning constraints may be necessary to further reduce the dose to the femoral heads. Further study is warranted to examine the clinical benefit of these dosimetric findings. No significant financial relationships to disclose.

Influence of submaximal isometric contractions of the hamstrings on electromyography activity and force while functioning as hip extensors

2020 ◽  
pp. 1-8
Author(s):  
Dasom Oh ◽  
Wootaek Lim
Keyword(s):  
Prone Position ◽  
Supine Position ◽  
Isometric Contraction ◽  
Muscle Length ◽  
Biceps Femoris ◽  
Emg Activity ◽  
Isometric Contractions ◽  
Significant Difference ◽  
Extension Force ◽  
Long Head

BACKGROUND: Although the medial and lateral hamstrings are clearly distinct anatomically and have different functions in the transverse plane, they are often considered as one muscle during rehabilitation. OBJECTIVE: The purpose of the study was to compare the electromyographic (EMG) activity between the prone position and the supine position during maximal isometric contraction and to additionally confirm the effect of submaximal isometric contractions on EMG activity of medial and lateral hamstrings, and force. METHODS: In the prone position, EMG activities of the long head of biceps femoris (BFLH) and semitendinosus (ST) were measured during the maximal isometric contraction. In the supine position, hip extension force with EMG activity were measured during the maximal and the submaximal isometric contractions. RESULTS: EMG activity in the prone position was significantly decreased in the supine position. In the supine position, there was a significant difference between the BFLH and ST during the maximal isometric contraction, but not during the submaximal isometric contractions. CONCLUSIONS: The dependence on the hamstrings could be relatively lower during hip extensions. When the medial and lateral hamstrings are considered separately, the lateral hamstrings may show a more active response, with increased muscle length, in clinical practice.

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