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The present investigation was carried out to study the response of physiological seedling vigour parameters of wheat as influenced by different seed invigoration techniques. Seeds of wheat variety UP 2565 were treated with electro- magnetic radiation (EMR) of 100 and 200 mT for one hour, hydropriming for 12 hours and plasma treatment for 6 minutes which were tested along the untreated seeds. The results revealed that all the seed invigoration treatments improved germination and seedling vigour parameters of wheat seed. The water absorption of plasma treated seeds increased by 42.2% and 23.9% after 6 and 12 hours of imbibitions period respectively over untreated seeds. The highest germination percentage was recorded in plasma treated seeds which was at par with electro- magnetic radiation (EMR) for 200 mT. The plasma treated seeds also emerged earlier than control and also took less time to emerge than rest of the treatment including untreated seeds.

BackgroundThis is a prospective study to evaluate the dosimetric benefits of treatment plan adaptation for patients who had undergone repeat computed tomography (ReCT)and re-planning due to treatment-induced anatomical changes during radiotherapy.Materials and MethodsThis study involved five head and neck cancer patients who had their treatment plan modified, based on weekly thrice imaging protocol. Impact of mid-course imaging was assessed in patients using ReCT and cone beam computed tomography (CBCT)-based dose verification. Patients were imaged, apart from their initial CT, during the course of their radiation therapy with a ReCT and on board imager CBCT (Varian Medical Systems Inc., Palo Alto, CA, USA). Each CBCT/CT series was rigidly registered to the initial CT in the treatment planning system Eclipse (Varian Medical Systems Inc.) using bony landmarks. The structures were copied to the current CBCT/CT series and, where needed, manually edited slicewise. The dose distribution from the treatment plan was viewed as of the current anatomy by applying the treatment plan the CBCT/CT series, and studying the corresponding dose–volume histograms for organs at risk doses.ResultsThe reduction of parotid volumes due to weight loss was observed in all patients, which means an increase in predicted mean doses of parotid when initial CT plan was re-calculated on ReCT and CBCT (Table 1). This explains the necessity of adaptive planning. The predicted mean dose of parotid glands was increased and constraints to spinal cord and skin were exceeded, so re-planning was performed.ConclusionsThe CBCT is a useful tool to view anatomic changes in patients and get an estimate of their impact on dose distribution. Re-planning based on imaging in head and neck patients during the course of radiotherapy is mandatory to reduce side effects.

The study of opinion offers answers to what the most critical problems are. Since sentiment analysis can be automated, judgements can be taken based on a significant amount of data rather than plain intuition, which is not always accurate. This paper focuses on the feature generation using Bag-of-Words and TF-IDF and the build model using the machine learning approach for sentiment analysis. The dataset used contains review of trip advisor on various hotels. This dataset consists of 20k reviews. Word cloud had been formed using sentiment ratings. Data was cleaned and pre-processed, and then applied Bow and TF-IDF for feature extraction. After implementation of classifiers, training and evaluation was performed. Evaluation metrics is used for measuring the accuracy of classifier. MultinomialNB obtained the highest accuracy in the realm of Bag of Word features and random forest outperformed in the case of TF-IDF out of three classifiers used to determine accuracy. We got 82% of the classification rate of MultinomialNB in Bag of Word and 78% accuracy in TF-IDF Random Forest.

Purpose: The aim of this study was to compare the delineation and treatment planning of 2 Phase based (end-expiration and end-inspiration) internal gross tumor volume (IGTV) with 10-phase based (four-dimensional [4D]) IGTV. Materials and Methods: Patients with lung tumors at different sites were selected for the study. The location of the tumor in Groups A, B, C were at the upper lobe (attached to the chest wall), middle lobe, and lower lobe, respectively. We contoured the GTV on each of the 10 respiratory phases of the 4D computed tomography (4DCT) data set. The combination of these GTVs produced the IGTV “All Phases.” GTV was also generated on the extreme respiratory phases. The combination of these two GTVs produced IGTV “2 Phases.” Treatment planning was done, and dose to organs at risks (OARs) were compared in both cases. Results: The average volume of IGTV “2 Phases” and IGTV “All Phases” for Group A were nearly same. However, for Group B and Group C, IGTV “2 Phases” were smaller than the IGTV “All Phases.” Lung-GTV doses were less in “exp-insp” phases than in “4DCT” for Groups B, C, whereas it was same for “expiration-inspiration” and “4DCT” in Patient A. Conclusion: Patients with tumor upper lobe tumor have no difference in tumor coverage and OARs sparing in the 2 Phase and all phases but middle lobe and lower lobe have a greater excursion during respiration and hence greater all phases IGTV.

 The aim of the study is to use Planned Dose Perturbation (PDP™) measurement-guided reconstruction method to estimate dynamic 4D dose and evaluate both 3D dose and DVH changes caused by target motion resulting from respiration. Five patients of Ca lung were selected for the study. Target and Organ at risks were (OARs) delineated on 4DCT data set of each patient. Dose of moving target vs. stationary target were simulated and compared for OARs and target by analyzing 3D dose and DVH(Dose Volume Histogram).There was almost 3.5% higher target maximum doses measured with moving target after applying the target motion trajectory data as compared to the stationary target whereas OARs doses were comparable. The results, clinically signifies the importance of motion management in lung tumors.

We proposed a method to reduce the volume of normal tissues irradiated by low doses in patients receiving CSI with RapidArc (RA) using Avoidance-Sector technique (RA+AS) and to compare its dosimetric implications with RA using full-arc (RA+FA) and 3D conformal technique (3DCRT). Four patients of CSI were retrospectively planned with 3DCRT, RA+FA, and RA+AS. Conformity-Index (CI), Homogeneity-Index (HI), and Paddick Gradient-Index (GI) were calculated. Quantitative evaluation was done using DVH analysis for PTVs and OARs. When compared with 3DCRT, GI, CI, and HI were favorable to RA based techniques. In comparison with 3DCRT the doses to OARs were lower with RA+AS with the difference being statistically significant in most instances. RA+AS significantly decreases the dose to OARs and their volumes receiving low doses in comparison with RA+FA and 3DCRT.

A robust method for voxel by voxel enhancement of Cone-beam CT (CBCT) images using a priori knowledge from the planning Computed Tomography (pCT) scan has been developed and used to evaluate the dosimetric accuracy of pCT based CBCT correction method for SBRT dose verification in lung metastasis. This is a retrospective study under which SBRT is carried out in 10 patients presented with lung metastasis. pCT images of patients were acquired and treatment planning was carried out on Varian Eclipse (V11) for 30 Gy in 5 fractions. Daily imaging using CBCT has been done for each patient with an On-Board Imaging system. CBCT is corrected using Matlab function considering CT as fixed and CBCT as moving, the images are registered. Planning target volume (PTV), lung, heart and spine were recontoured on uncorrected CBCT and corrected CBCT separately and the calculated plan on CT is recalculated on both the CBCTs. The dose distribution between the pCT and both the CBCT images were compared. A paired sample test was performed to test the variations. The distribution of pixel intensity of corrected CBCT is closer to the pCT than the uncorrected CBCT. The maximum percentage difference between the corrected CBCT and pCT is 1% in PTV evaluation, which is 3.5% between uncorrected CBCT and pCT. The method increases the accuracy of CBCT density values and enabling the use of CBCT images for dose calculation in radiotherapy.

Introduction: While planning radiation therapy (RT) for a carcinoma of the urinary bladder (CaUB), the intra-fractional variation of the urinary bladder (UB) volume due to filling-up needs to be accounted for. This internal target volume (ITV) is obtained by adding internal margins (IM) to the contoured bladder. This study was planned to propose a method of acquiring individualized ITVs for each patient and to verify their reproducibility. Methods: One patient with CaUB underwent simulation with the proposed ‘bladder protocol’. After immobilization, a planning CT scan on empty bladder was done. He was then given 300 ml of water to drink and the time (T) was noted. Planning CT scans were performed after 20 min (T+20), 30 min (T+30) and 40 min (T+40). The CT scan at T+20 was co-registered with the T+30 and T+40 scans. The bladder volumes at 20, 30 and 40 min were then contoured as CTV20, CTV30 and CTV40 to obtain an individualized ITV for our patient. For daily treatment, he was instructed to drink water as above, and the time was noted; treatment was started after 20 min. Daily pre- and post-treatment cone beam CT (CBCT) scans were done. The bladder visualized on the pre-treatment CBCT scan was compared with CTV20 and on the post-treatment CBCT scan with CTV30. Results: In total, there were 65 CBCT scans (36 pre- and 29 post-treatment). Individualized ITVs were found to be reproducible in 93.85% of all instances and fell outside in 4 instances. Conclusions: The proposed bladder protocol can yield a reproducible estimation of the ITV during treatment; this can obviate the need for taking standard IMs.

The authors thank Dr. Gagan Saini and coworkers [1] for their astute comments on cranio-spinal irradiation (CSI) treatment using Volumetric Modulated Arc Therapy (VMAT). Indeed no data related to V5Gy for lungs were reported in our paper on CSI [2], this metric being a reported predictor for radiation induction pneumonitis. To complete the lack of information, the rV5Gy (volume of lungs spared from doses > 5 Gy) values a rising from the CSI plans in our study are in average 850 cm (range 610–1590 cm), or 51% if the common V5Gy parameter is analysed. We are cognizant that several other dose-metrics, other than the one proposed by Saini et al. [1] might also be of value when assessing the pneumonitis probability. In the two other articles, where the end point is the radiation induction pneumonitis, V5Gy remains highly correlated with other parameters as rV65Gy [3] or V10Gy–V20Gy and MLD [4]. We have also to stress that the dose prescriptions of the lung and oesophageal cancers series [3–5] cited by the authors are indisputably higher than what are used in CSI treatments (from 12 Gy to 36 Gy). This fact inevitably changes the global lung irradiation: if no high doses are delivered to the lungs, it is not clear, at least from literature, if the V5Gy remains as significant for radiation induction pneumonitis, or it plays mainly a role for damage recover from high dose irradiation. Moreover, other non-radiation related factors, such as those proposed by Wang et al. [3] may consequentially increase the risk of lung toxicity in non-CSI series. Some additional difficulties could derive from the lung volumes described in the two Wang papers [3,4] (average of 3649 and 3349 cm of both lungs together, with maximum volumes of 6459 and 7871 cm), strongly higher with respect to our patients (average of 2495 cm, excluding the child, with a maximum value of 3030 cm). The second important point mentioned by Dr. Saini [1] was related to the dose calculation accuracy in the low dose regions, 322 Letters to the Editor / Radiotherapy and Oncology 102 (2012) 321–323

To study the effect of respiration (end expiration [EE] and end inspiration [EI]) on tumor and normal structure doses and volumes in carcinoma lung. Five patients with squamous cell carcinoma of the lung were selected for this retrospective study. Computerized tomography (CT) data set was subsequently obtained for all patients in EE and EI phases of the respiratory cycle. Gross tumor volume, clinical target volume, planning target volume (PTV) and organs at risk were delineated in both EE and EI on CT data sets. Prescribed dose was 60 Gy in 30 fractions for all patients. The PTV coverage and organs at risks (OARs) were evaluated using radiation therapy oncology group conformity indices (CI) and homogeneity indices (HI) and volume doses respectively. The CI and HI were comparable for both phases. Volumes of all OARs were comparable except the lung. OAR doses were almost same in both phases. Significantly higher normal lung volume was found in the EI phase. Based on our dosimetric data and statistical analysis we conclude that both EE and EI are dosimetrically comparable.

Purpose: The aim of this study was to compare the delineation and treatment planning of two phase‐based (the end‐expiration and the endinspiration phases) IGTV (Internal Gross Tumor Volume) with ten‐phase based (4D) IGTV. Methods: Two patients with lung tumors at different sites were selected for the study.The location of the tumor in Patient A was at the upper lobe(attached to the chest wall) of the left lung.In patient B the location was the middle lobe of right lung.We contoured the GTV on each of the ten respiratory phases of the 4D‐CT data set.The combination of these GTVs produced the IGTV .GTV was also generated on the extreme respiratory phases 0% phase = peak inhalation, 50% phase = peak exhalation).The combination of these two GTVs produced IGTV .Treatment planning was done and dose to OARs were compared in both end expiration inspiration(EEI) and 4DCT study set. Results: IGTV (175cc)and IGTV (180 cc) for Patient A were nearly same. But for Patient B, IGTV (80cc) was smaller than the IGTV (181 cc).C.I.(Conformity Index) was found better in EEI and 4DCT in Patient A than in Patient B due to the limitation of the AAA algorithm in the low density region.Lung‐GTV doses were less in EEI scan than in 4DCT for Patient B whereas it was the same for EEI and 4DCT in Patient A. Conclusion: The study shows the patients with tumor in upper lobe have no difference in tumor coverage and OARs sparing in the EEI and 4DCT. However,tumors in middle lobe have a greater excursion during respiration and hence greater all phase IGTV.We suggest performing a 4D scan and EEI scan both,for these categories of patients in order to include the tumor excursion due to breathing. Conflict of Interest: Nil; Funding Support: Required if possible