This study aimed to analyze and relate the population interest through information search trends on Nutrition and Healthy Diet (HD) with the Occupational Health (OH). Ecological and correlational study of the Relative Search Volume (RSV) obtained from Google Trends query, segmented in two searched periods concerning antiquity; date of query: 20 April 2021. The RSV trends for the analyzed three Topics were: Nutrition (R2 = 0.02), HD (R2 = 0.07) and OH (R2 = −0.72). There was a good positive correlation between Nutrition and OH (R = 0.56, p < 0.001) and a moderate one between HD and OH (R = 0.32, p < 0.001). According to seasons, differences were verified between RSV means in the Topics HD (p < 0.01) and OH (p < 0.001). Temporal dependence was demonstrated on Nutrition searches (Augmented Dickey–Fuller = −2.35, p > 0.05). There was only a significant relationship between the RSV Topic HD (p < 0.05) for the Developing and Least Developed countries. The data on the analyzed RSV demonstrated diminishing interest in the search information on HD and OH as well as a clearly positive trend change in recent years for Nutrition. A good positive correlation was observed between the RSV of nutrition and OH whereas the correlation between HD and OH was moderate. There were no milestones found that may report a punctual event leading to the improvement of information searches. Temporal dependence was corroborated in the RSV on Nutrition, but not in the other two Topics. Strangely, only an association was found on HD searches between the Developing and Least Developed Countries. The study of information search trends may provide useful information on the population’s interest in the disease data, as well as would gradually allow the analysis of differences in popularity, or interest even between different countries. Thus, this information might be used as a guide for public health approaches regarding nutrition and a healthy diet at work.

Purpose: In the commissioning and QA of surface isotope‐based applicators, source‐indexer distance (SID) has a great influence in the flatness, symmetry and output. To these purposes, methods described in the literature are the use of a special insert at the entrance of dwell chamber or radiochromic films. Here we present the experience with a micro‐chamber array to perform the commissioning and QA of Valencia applicators. Methods: Valencia applicators have been used, the classic and the new extra‐shielded version. A micro‐chamber array has been employed, 1000 SRS (PTW), with 977 liquid filled, 2.3×2.3×0.5 mm3 sized ion chambers covering 11×11 cm2, which spacing is 2.5 mm in the central 5.5×5.5 cm2, dedicated mainly in principle, in conjunction with Octavius 4D (PTW), to IMRT, VMAT, SBRT verifications. Verisoft software that allows for 3D and planar analysis has been used to evaluate the results. Applicators were located on the surface of the array. To verify the SID, measurements corresponding to the reference value, SID ± 1 mm and SID ± 2 mm were acquired (integration time was fixed in order to discard the influence of the source entrance/exit). Once SID was determined, standard protocol treatments corresponding to 3 Gy and 7 Gy were acquired in order to establish typical patient dose distribution. Results: The method is fast and sensitive. The SID obtained was 1321 mm which is the nominal value included in the applicator manual. For example at 1319 mm an asymmetry of ±8% with respect to the central value was measured, along with a central deviation of −4% referred to 1321 mm. Conclusion: A practical method for the commissioning and QA of Valencia applicators has been described. It has been shown that it is an efficient and accurate tool for these purposes as well as for the verification of the absolute output constancy.

Purpose:With the establishment of the IGRT as a standard technique, the extra dose that is given to the patients should be taken into account. Furthermore, it has been a recent decrease of the dose threshold in the lens, reduced to 0.5 Gy (ICRP ref 4825‐3093‐1464 on 21st April, 2011). The purpose of this work was to evaluate the extra dose that the lens is receive due to the Cone‐Beam (CBCT) location systems in Head‐and‐Neck treatments.Methods:The On‐Board Imaging (OBI) v 1.5 of the two Varian accelerators, one Clinac iX and one True Beam, were used to obtain the dose that this OBI version give to the lens in the Head‐and‐Neck location treatments. All CBCT scans were acquired with the Standard Dose Head protocol (100 kVp, 80 mA, 8 ms and 200 degree of rotation). The measurements were taken with thermoluminescence (TLD) EXTRAD (Harshaw) dosimeters placed in an anthropomorphic phantom over the eye and under 3 mm of bolus material to mimic the lens position. The center of the head was placed at the isocenter. To reduce TLD energy dependence, they were calibrated at the used beam quality.Results:The average lens dose at the lens in the OBI v 1.5 systems of the Clinac iX and the True Beam is 0.071 and 0.076 cGy/CBCT, respectively.Conclusions:The extra absorbed doses that receive the eye lenses due to one CBCT acquisition with the studied protocol is far below the new ICRP recommended threshold for the lens. However, the addition effect of several CBCT acquisition during the whole treatment should be taken into account.

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Purpose:To study the performance of Dosimetry Check (DC), an EPID‐based dosimetry software, which allows performing transit dosimetry, in low density medium, by comparing calculations in‐phantom, and analysing results for 15 lung patients.Methods:DC software (v.3.8, pencil beam‐based algorithm) has been tested, for plans (Eclipse v.10.0 TPS) delivered in two Varian Clinac iX equipped with aS1000 EPIDs.In the CIRS lung phantom, comparisons between DC and Eclipse (Acuros) were performed for several plans: (1) four field box; (2) square field delivered in arc mode; (3) RapidArc lung patient plan medially centred; (4) RapidArc lung patient plan centred in one lung. Reference points analysed: P1 (medial point, plans 1–3) and P2 (located inside one lung, plan 4).For fifteen lung patients treated with RapidArc, the isocentre and 9 additional points inside the PTV as well as the gamma passing rate (3%/3mm) for the PTV and at the main planes were studied.Results:In‐phantom:P1: Per‐field differences in plan 1: good agreement for AP‐PA fields; discrepancy of 7% for the lateral fields. Global differences (plans 1–3): about 4%, showing a compensating effect of the individual differences.P2: Global difference (plan 4): 15 %. This represents the worst case situation as it is a point surrounded by lung tissue, where the DC pencil beam algorithm is expected to give the greater difference against Acuros.Lung patients: Mean point difference inside the PTV:(5.4±4.2) %. Gamma passing rate inside the PTV:(45±12) %.Conclusion:The performance of DC in heterogeneous lung medium was studied with a special phantom and the results for 15 patients were analysed. The found deviations show that even though DC is a highly promising in vivo dosimetry tool, there is a need of incorporating a more accurate algorithm mainly for plans with low density regions involved.