Radiation Physics

PV QA 3 - Poster Viewing Q&A 3

TU_19_3300 - To Evaluate the Use of a Homemade Self-Held Respiration Monitoring Device (SHRMD) for Deep Inspiration Breath Hold (DIBH) Radiation Therapy to Left Breast Cancer Patients

Tuesday, October 23
1:00 PM - 2:30 PM
Location: Innovation Hub, Exhibit Hall 3

To Evaluate the Use of a Homemade Self-Held Respiration Monitoring Device (SHRMD) for Deep Inspiration Breath Hold (DIBH) Radiation Therapy to Left Breast Cancer Patients
K. M. Ku1, Y. P. Ng2, S. K. Yu3, C. W. Kong IV4, W. M. Kwok2, W. L. Mui5, C. M. C. Wong1, and G. Chiu6; 1Department of Radiotherapy, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong, 2Hong Kong Sanatorium and Hospital, Hong Kong, Hong Kong, 3Medical Physics & Research Department, Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong, 4Hong Kong Sanatorium & Hospital, Happy Valley, Hong Kong, 5Hong Kong Sanatorium and Hospital, Happy Valley, Hong Kong, 6Department of Radiotherapy, Hong Kong Sanatorium & Hospital, Hong Kong, Hong Kong

Purpose/Objective(s): This prospective observational study is to quantify: 1) the inter-fraction reproducibility; 2) the intra-fraction variability; and 3) the intra-beam variability of patient’s breath-holding ability by using the Self-Held Respiration Monitoring Device (SHRMD).

Materials/Methods: Fifteen patients with left breast cancer underwent breast conservative surgery and plan for tangential opposing chest wall radiotherapy using Deep Inspiration Breath Hold (DIBH) technique were selected. The SHRMD consists of two parts: 1) Mechanical sensor, which was placed between the xiphoid process and umbilicus, connecting with a controller to detect and reflect patient’s chest wall motion and provide mechanical motion data to the computer software. The controller also gave a green light signal together with alarm sound to guide the patient during respiration monitoring by indicating the optimum level of breathing threshold. 2) Computer software, which recorded the patients breathing pattern by transferring the sensor mechanical movement into digital readings. By using this device, patient’s actual breathing motion were detected and monitored. The treatments were delivered in a linear accelerator with 6MV photon for 40Gy to 43.2Gy at 100% isodose level in 15 to 16 daily fractions. Megavoltage cine images were acquired in Beam’s Eye View (BEV) during treatment. The average fractional lung depths were used to evaluate the inter-fraction setup reproducibility; the average lung depths variability between medial and lateral fields were used to evaluate the intra-fraction variability; and range of lung depths within each beam were used to evaluate the intra-beam variability.

Results: The median age of the 15 patients was 47.5 (range = 39-63). The inter-fraction overall mean error (M), SD of the systematic error (∑) and SD of the random error (σ) were 0.01cm, 0.06cm and 0.2cm respectively. The intra-fraction overall mean error (M), SD of the systematic error (∑) and SD of the random error (σ) were 0.04cm, 0.07cm and 0.2cm respectively. And the intra-beam SD variability was 0.07cm.

Conclusion: Results showed that patients undergoing radiotherapy to left breast cancer are able to perform a stable and reproducible DIBH by using the SHRMD.

Author Disclosure: K. Ku: None. C. Kong: None. W. Mui: None.

Send Email for Chi Wah Kong


Assets

TU_19_3300 - To Evaluate the Use of a Homemade Self-Held Respiration Monitoring Device (SHRMD) for Deep Inspiration Breath Hold (DIBH) Radiation Therapy to Left Breast Cancer Patients



Attendees who have favorited this

Please enter your access key

The asset you are trying to access is locked. Please enter your access key to unlock.

Send Email for To Evaluate the Use of a Homemade Self-Held Respiration Monitoring Device (SHRMD) for Deep Inspiration Breath Hold (DIBH) Radiation Therapy to Left Breast Cancer Patients