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OBJECTIVE To study the dosimetric characteristics and treatment plan complexity of Intensity-Modulated Radiotherapy (IMRT) and RapidArc (RA) techniques for Flattening Filter (FF) and Flattening Filter-Free (FFF) beams in the treatment of cervical cancer. METHODS A cohort comprising twenty post-operative cervical cancer patients was selected for this study. Four distinct sets of treatment plans were generated utilizing both RA and IMRT techniques employing FFF and FF beams. The dosimetric parameters were subjected to a comprehensive comparison, encompassing considerations such as the coverage of the Planning Target Volume (PTV), Conformity Index, Homogeneity Index, Heterogeneity Index, Gradient Index, Organ at Risk doses, and Peripheral doses. RESULTS The dose-volume parameters exhibited a significant difference in V95 between RA_FF and FFF plans. However, V98 demonstrated a higher percentage of coverage with FF beams for both IMRT and RA planning techniques (p<0.01). IMRT and RA plans resulted in a percentage reduction in V45 for the bladder and rectum with the FFF beam. Furthermore, the FFF beam showed a significant increase in MUs and a significant reduction in V30% for the femoral head for both IMRT and RA plans. No difference was observed in normal tissue sparing with the FFF beam for both techniques. CONCLUSION Dosimetrically, FF and FFF beam plans exhibit comparable target coverage and OAR sparing for postoperative cervical carcinoma using both IMRT and RA techniques. However, in terms of plan quality, RA_FFF plans demonstrate a superior coverage index, conformity, and better sparing of normal tissue compared to IMRT_FFF, except for homogeneity. [ABSTRACT FROM AUTHOR]

Aim: This study aimed to evaluate the Deformable Image Registration (DIR) software of Mirada® and Velocity® using quantitative measures as per the recommendation based on Task Group TG- 132. Materials and Methods: Task Group 132 has provided geometric and anatomic virtual phantoms for quality assurance which were imported and contoured on the reference image, followed by DIR and then the contours were propagated on all the CT/CBCT data sets with different offsets and orientation of geometric and anatomic virtual phantom using Mirada and Velocity. Analysis was performed using the Dice Similarity Coefficient (DSC), Mean Distance to Agreement (MDA), Housdorff (HD) and Target Registration Error (TRE). The results were compared to find the difference in significance using a Paired t-test with a significance level set at 5%. Results: The obtained statistical result is listed below, considering the Geometric phantom, with regards to DSC, Mean and SD values obtained for Mirada and Velocity is 0.955 ± 0.348 and 0.965 ± 0.418 respectively with the p-value coming at 0.013 indicating a significant difference. Considering MDA, a significant difference of p-value of 0.001 was found between Mirada and Velocity with the former having 0.668 ± 0.684 compared to 0.381 ± 0.424 of the latter. For HD, Mirada obtained a mean value of 3.464 ± 2.091 in comparison with 2.202 ± 1.215 of Velocity. As for TRE, three fiducials within the phantom were considered and Mirada had a mean value of 1.037 mm while Velocity had 1.338 mm. While analyzing the Anatomic phantom, DSC values for Mirada and Velocity were 0.946 ± 0.031 and 0.944 ± 0.313 respectively indicating no significance. Likewise, no significance was found considering MDA (Mirada: 0.435 ± 0.235, Velocity: 0.449 ± 0.242). Regarding HD, Mirada obtained 4.216 mm while Velocity had 4.233 mm showing exceptional compliance. The mean value of TRE for three fiducials was found to be less than 1 mm it's also found significant difference. Conclusion: This study highlights the strengths and differences between Mirada and Velocity in DIR for adaptive radiotherapy. While both software applications excel in DSC, MDA and HD, the observed difference in TRE indicates a potential advantage of Mirada in achieving better image registration, especially in landmark-based registration scenarios. [ABSTRACT FROM AUTHOR]

Background: Acute gastroenteritis is one of the common causes for which pediatric patients are admitted. The present study was conducted to assess clinical profile and pattern of water and sodium disturbances in children suffering from diarrhoea with dehydration. Materials & Methods: 110 children of age 6 months to 5 years admitted in Pediatric ward with diarrhoea with dehydration of both genders were selected. Children were managed as per standard WHO protocol, adequately hydrated and serum electrolytes were repeated as and when required. Hyponatremia was defined as serum sodium 145 meq/L. Results: The mean serum sodium level at admission was 135.6mEq/L, duration of diarrhoea was 14.2days, number of loose stools per day was 11.5, duration of vomiting episodes was 2.9 days, number of vomiting episodes per day was 3.4 and duration of hospital stay was 3.8days. Hyponatremia was seen in 14 male and 16 females. Hypernatremia in 16 males and 9 females and isonatremia in 37 males and 18 females. Age group 6 months- 1 year had 10, 10 and 20 and 1 year- 5 years had 20, 15 and 35. Nutritional status was normal seen in 16, 12 and 22, grade I PEM in 6, 4 and 5, grade II PEM in 4, 5 and 4, grade III PEM in 3, 3 and 2 and grade IV PEM in 2, 1 and 2 having hyponatremia, hypernatremia and isonatremia respectively. The difference was significant (P< 0.05). Conclusion: The incidence of hyponatremia and hypernatremia in children is quite high (nearly 40%). Malnourished children and children taking improperly diluted WHO ORS were at a significantly higher risk of developing hyponatremia or hypernatremia. [ABSTRACT FROM AUTHOR]

In this communication, a quad-port MIMO antenna with quad-band is proposed, for X-band (8-12) GHz and Ku-band (12-18) GHz applications; particularly applicable for radar and satellite applications. The proposed antenna has measured |S11|, |S22|, |S33| & |S44| < -10 dB, Isolation (|S21|, |S31|, |S32|, |S41|, |S42| & |S43|) < -20 dB and maximum peak gain of 11.37 dBi at entire port 1- 4. ECC value has obtained between ports 1-2, 1-3 & 1-4 is < 0.031. DG originated between ports 1-2, 1-3 & 1-4 is in the range of 9.994-9.999 (dB), channel capacity loss (CCL) < 0.086 bits/sec/Hz, VSWR < 1.78, TARC < 0 dB and radiation efficiency is more than 62% at entire operating band has obtained. The novelty of radiating elements are placed orthogonally to each other and increased bandwidth, gain and other antenna characteristics by having rectangular and circular slot cuts as compared to the reported published paper. The simulated and measured results of the proposed antenna have been validated and minor deviation between simulated and measured results has been observed. [ABSTRACT FROM AUTHOR]