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Introduction: Globally, intensity-modulated radiation therapy (IMRT) is considered as highly precise and accurate method of radiotherapy planning. This technique amplifies spatial dose distribution conformity by modulating the intensity of radiation beams in each sub-volume. Additionally, it can reduces the dose to surrounding critical organs and deliver the planned dose to targets with the nominal risk of side effects. Material and Methods: In this study, 13 patients with head and neck cancer were randomly taken for analysis. The IMRT and Rapid Arc plans were generated for each case in the Eclipse treatment planning system, version 11.0. There were seven to nine beams deployed in IMRT plan, while Rapid Arc plans were performed using two arcs with opposite direction of rotation. Portal dosimetry plans were created and analyzed before executing the plan on the patient. Results: The mean of V95%(Target’s volume covered by 95% isodose line)was 97.89% and 97.47% for Rapid Arc and IMRT plans, respectively. Moreover, mean standard deviations were found 1.93 and 1.70 in Rapid Arc and IMRT plans, respectively. The mean gamma index was97.55% and 98.43% in Rapid Arc and IMRT, respectively. Conclusion: IMRT technique was slightly better in the treatment of head and neck cancer compared to the Rapid Arc method. The only advantage of Rapid Arc was saving the treatment time by two to three times on an average compared with IMRT. It is prudent to use IMRT technique in head and neck cancer treatment.

BackgroundAcross the history of radiotherapy, with gradual technological progress and various methods of irradiation, the purpose has always been to deliver homogeneously 100% of the prescribed dose to 100% of the target volume containing the identifiable tumour and/or tumour cells potentially present while limiting the dose to adjacent normal tissues.Material and methodsThe formula for triple point conformity scale is: CS3=(V95+V100+V105)/3VT. (a) Lower limit determination: CS3=(VT+0·93 VT+0·0)/3VT=0·643; (b) Upper limit determination: in order to find out an empirical relation in between V105 and VT, we studied over 593 cancer patients of various sites by taking planning target volume as target, and an empirical relation is derived out as: V105/VT=0·0007. Hence, CS3=(VT+VT+0·0007 VT)/3VT=0·6667~0·667.ResultUpper and lower limits of CS3 have been calculated at 0·643 and 0·667, respectively. Maximum value of CS3 index is recorded 0·656 while minimum value is 0·478.DiscussionThe CS3 scale constitutes an attractive tool because it could facilitate decisions during analysis of various treatment plans proposed for conformal radiotherapy. Its major advantages are its simplicity and integration of multiple parameters.ConclusionThe triple point conformity scale (CS3) provides better qualitative information about radiotherapy plans as compared to other conformity indices. This study advises the users to use the CS3 scale to evaluate a conformal radiotherapy plan which encompasses a wide range of relevant clinical volumes, and is able to extract qualitative dosimetric information.

Introduction: Single isocentre half-beam block (HBB) technique permits the avoidance of hot and cold spots. This technique is very useful in sparing the underlying ipsilateral lung and heart, if the left breast is treated. The major advantage of this technique is that it facilitates the complete sparing of both contralateral breast and lung. Regarding this, the present study aimed to analyse the dosimetric results obtained from the HBB technique in the treatment of breast cancer using three different algorithms. Materials and Methods: For the purpose of the study, a total dose of 5000 cGy was prescribed to the planning target volume (PTV) in 25 fractions per fraction daily, five days a week. The PTV was derived by using 4-7 mm isotropic expansion of the clinical target volume (CTV) clipping 1-3 mm from the patient’s surface in the breast-conserving cases. Three plans were created for each patient using three different algorithms, including convolution, fast superposition, and superposition with the same parameters. Results: The mean doses of PTV-breast and CTV-supraclavicular fossa (SCF) were tabulated and analysed. In the PTV-breast, the maximum and minimum mean doses were 5428.8 and 4930.2 cGy, which were observed in the fast superposition and convolution algorithms, respectively. In the CTV-SCF, the maximum and minimum mean doses were 5428.8 and 5126.8 cGy, respectively, detected in only fast superposition algorithm. Conclusion: As the findings of the present study indicated, the convolution algorithm gives slightly better dosimetric results in breast cancer treatment, compared to the fast superposition and superposition algorithms. Therefore, it is prudent to apply the HBB technique with convolution algorithm using the Elekta XiO planning system in the treatment of breast cancer including supraclavicular lymph node metastasis.

Background: Across the history of radiotherapy, wedges are generally used to modify the shape of isodose lines to achieve desired clinical dose coverage to the target and to reduce the hot spot as well. Aim: The main aim of this study was to analyse and compare the dosimetric properties of Varian’s physical and enhanced dynamic wedges, and their dosimetric impact on radiotherapy plan (3D-Conformal). Materials and Methods: All plans were generated and evaluated in Varian’s eclipse planning system. For comparing the isodose line alteration, the plans were prepared in water phantom with field of size 10 cmx 10 cm. Wedges of angle 15°, 30°, 45° and 60° were used for generating isodose lines in the current study. All wedge factors were measured in water phantom using FC65 farmer type chamber. Discussion: In the current study, the dosimetric characteristics of EDW and PW were analyzed and compared. For analyzing the impact of EDW and PW, 22 patients were taken into consideration, and 50 Gy dose was prescribed to PTV in 25 fractions. Conclusion: The analysis of EDW and PW shows slightly different dosimetric features. EDW gives better target’s coverage, less hyper dose and comparatively less MUs as compare to PW. Hence the use EDW in 3D-conformal radiotherapy plan is a prudent practice.

An indoor and outdoor experiment was conducted at Shyamsunderpur, Mayurbhanj, Odhisa to test the efficacy of the artificial diet, Tasar Amrit on the young aged Antheraea mylitta silkworm larvae. The results of the experiment reveal that survival and effective rate of rearing (ERR) was higher when larvae were brushed on Tasar Amrit (75 and 42.45%) in contrast to complete outdoor rearing (44 and 33.56 %). Uniform moulting was also observed in the larvae fed with Tasar Amrit.

An experiment of outdoor rearing was conducted with the available Sukinda (TV) stock of BSM&TC, Sundargarh (SG), CTSSS, Lakha (CTS) and CTR&TI, Ranchi. The objective of this activity is to utilize economic wild life, conserving the associated environment for sustainable rural and tribal development (Raffi and Ramanujam, 2001; Gill and Lal, 2002; Mahapatra, 2009).The crop performance of SG showed highest cocoon yield i.e., 83 cocoons / dfl in 1st crop followed by 80 cocoons / dfl in 3rd crop and 42 cocoons / dfl during 2nd crop. Yellow coloured cocoons dominated (94-96%) the population in all the three crops. The cocoon weight, Shell weight and Silk Ratio were (9.72g, 1.07g&11 %) in 1st crop,(9.77g,1.05g & 10.75%) in 2nd crop and (11.11g,1.79g & 16.11%) in commercial third crop season. The ERR were 41.64 %, 50.00 % and 74.51% in 1st, 2nd and 3rd crop respectively. This approach for semi-domesticated and commercially exploited Sukinda ecoraces can further enhances their potential because of better inherent performance levels under in situ (Suryanarayana and Srivastava, 2005) over the current basic and commercial stocks maintained ex situ.