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AIM: To identify the most reproducible technique of patient positioning and immobilization during pelvic radiotherapy. BACKGROUND: Radiotherapy plays an important role in the treatment of pelvic malignancies. Errors in positioning of patient are an integral component of treatment. The present study compares two methods of immobilization with no immobilization with an aim of identifying the most reproducible method. MATERIALS AND METHODS: 65 consecutive patients receiving pelvic external beam radiotherapy were retrospectively analyzed. 30, 21 and 14 patients were treated with no-immobilization with a leg separator, whole body vacuum bag cushion (VBC) and six point aquaplast immobilization system, respectively. The systematic error, random error and the planning target volume (PTV) margins were calculated for all the three techniques and statistically analyzed. RESULTS: The systematic errors were the highest in the VBC and random errors were the highest in the aquaplast group. Both systematic and random errors were the lowest in patients treated with no-immobilization. 3D Systematic error (mm, mean ± 1SD) was 4.31 ± 3.84, 3.39 ± 1.71 and 2.42 ± 0.97 for VBC, aquaplast and no-immobilization, respectively. 3D random error (mm, 1SD) was 2.96, 3.59 and 1.39 for VBC, aquaplast and no-immobilization, respectively. The differences were statistically significant between all the three groups. The calculated PTV margins were the smallest for the no-immobilization technique with 4.56, 4.69 and 4.59 mm, respectively, in x, y and z axes, respectively. CONCLUSIONS: Among the three techniques, no-immobilization technique with leg separator was the most reproducible technique with the smallest PTV margins. For obvious reasons, this technique is the least time consuming and most economically viable in developing countries.
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INTRODCTION: Optimal time management is of utmost importance in the radiotherapy department. Inappropriate allocation of time slots leads to prolonged waiting times and decreased patient satisfaction during external beam radiotherapy. The present study tests a logical model to improve the waiting time for the patients. MATERIALS AND METHODS: The treatment time, waiting time, and causes of delay were studied from November 4, 2014, to July 24, 2015. New rules were framed for treatment slot allocation from December 26, 2014. The treatment slots were classified based on the treatment technology (three-dimensional conformal radiotherapy and intensity-modulated radiotherapy) with inclusion of "buffer slots" and patient education. The results were compared before and after rules. RESULTS: A total of 1032 time slots were analyzed, of which 225 "before rules" and 807 "after rules," respectively. There was a significant reduction in the average waiting time for treatment in on-time patients (median [interquartile range (IQR)] of 25.2 min [31.75] vs. 3 min [3.5]; P< 0.00001) as well as in late-coming patients (median [IQR] of 38.2 min [13.795] vs. 21.11 min [12.75]; P= 0.00006). 59.7% (71 patients) of the treatment was delayed "before rules" as opposed to 32.2% (137 patients) "after rules" in on-time patients. Due to better patient education, there was a significant improvement in the patient punctuality toward the allotted time. CONCLUSION: The treatment slots classified based on the teletherapy technique with buffer slots, and patient education helps in better time management on linear accelerator. This methodology significantly reduces waiting time and thereby the number of patients having delay in the treatment.