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Treatment of giant cell arteritis (GCA) aims initially to prevent acute visual loss, and subsequently to optimise long-term quality of life. Initial prevention of acute visual loss in GCA is well-standardised with high-dose glucocorticoid therapy but in the longer term optimising quality of life requires tailoring of treatment to the individual. The licensing of the IL-6 receptor inhibitor tocilizumab combined with advances in vascular imaging have resulted in many changes to diagnostic and therapeutic practice. Firstly, GCA is a systemic disease that may involve multiple vascular territories and present in diverse ways. Broadening of the "spectrum" of what is called GCA has been crystallised in the 2022 GCA classification criteria. Secondly, the vascular inflammation of GCA frequently co-exists with the extracapsular musculoskeletal inflammation of the related disease, polymyalgia rheumatica (PMR). Thirdly, GCA care must often be delivered across multiple specialities and healthcare organisations requiring effective interprofessional communication. Fourthly, both GCA and PMR may follow a chronic or multiphasic disease course; long-term management must be tailored to the individual patient's needs. In this article we focus on some areas of current rheumatology practice that ophthalmologists need to be aware of, including comprehensive assessment of extra-ocular symptoms, physical signs and laboratory markers; advanced imaging techniques; and implications for multi-speciality collaboration., (© 2024. The Author(s).)

Purpose: To critically review the clinical factors, dosimetry, and their correlation with early outcomes in patients with chordomas and chondrosarcomas treated with pencil beam scanning (PBS) proton beam therapy (PBT)., Methods and Materials: Consecutive 64 patients diagnosed with chordoma or chondrosarcoma treated at our center were studied. Patient, tumor, and treatment-related factors including dosimetry were captured. Early and late toxicities and early outcomes were evaluated and correlated with clinical and dosimetric factors using standard statistical tools., Results: The median age of patients was 39 years (range, 4-74 years), and most common site was skull base (47%), followed by sacrum (31%) and mobile spine (22%). The median prescription dose to the high-risk clinical target volumes for chordoma and chondrosarcoma was 70.4 cobalt gray equivalent (CGE) and 66 CGE at 2.2 CGE per fraction, respectively. At presentation, 55% presented after a recurrence/progression of which 17% had received previous radiation and 32% had a significant neural compression. At the time of PBT, 25% of patients had suboptimal neural separation. Three-fourths of patients had at least an acceptable target coverage. Although 11% had a tier 1 compromise (gross tumor volume [GTV] D98 < 90%), 14% had a tier 2 compromise (GTVD98 < 59 CGE). With a median follow-up of 27.5 months, 2-year local control and progression-free survival was 86.7% and 81.8% for chordomas and 87.5% and 77.1% for chondrosarcomas, respectively. Residual GTV of >25 cm 3 and a tier 2 compromise were associated with inferior local control (hazard ratio [HR], 0.19; P = .019; HR, 0.061; P = .022, respectively) and progression-free survival (HR, 0.128; P = 0.014; HR, 0.194; P =.025, respectively) on multivariate analysis. Despite multiple surgeries, a majority presented with recurrent disease and previous radiations and grade 3 acute and late toxicities were limited and comparable with others in the literature., Conclusions: Despite multiple surgeries, adequate neural separation was challenging to achieve. Severe dosimetric compromise (GTV D98 < 59 CGE) led to inferior early outcomes. Adequate neural separation is key to avoiding dosimetric compromise and achieving optimal local control., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 Published by Elsevier Inc. on behalf of American Society for Radiation Oncology.)

Aim: To carry out a comprehensive critical appraisal of image-guided intensity-modulated proton therapy practice for craniospinal irradiation (CSI)., Materials and Methods: An image-guided intensity-modulated proton therapy database of 45 consecutive paediatric patients with central nervous system embryonal malignancies treated between January 2019 and April 2022 were critically appraised for demography, diagnosis, treatment planning strategy and treatment delivery accuracy., Results: Most patients (median age: 7.5 years; male:female ratio: 34:11) had medulloblastoma (56%), followed by recurrent ependymoma (19%), pinealoblastoma (5%), germ cell (5%) and others (15%). The dose to the planning target volume-craniospinal (PTV-CS; length 39.06-79.59 cm) varied from 21 to 35 GyRBE, whereas the combined median dose to craniospinal and boost was 54 GyRBE. In all patients, the 95% isodose line covered the cribriform plate completely and optic nerves mostly, with a median V95% of 100% and 82.96%, keeping Dmax to the lens <3.9 GyRBE. In skeletally immature patients (88.38%), the anterior vertebral body was completely covered in 18.18% and underdosed in 70.15% of the cases, resulting in a median Dmean of 10.11 GyRBE to the oesophagus. Lateral spine coverage was maintained on the edges of the vertebral body in 52.2%, whereas it extended beyond in 48.8%. The median V98% for clinical target volumes and V95% for PTVs of the brain, spine and craniospinal were >97%, with excellent conformity (0.89) and homogeneity (0.07) indices for PTV-CS. All neurological organs at risk received a median Dmax ranging from 36 to 44 GyRBE from the combined CSI and boost regimens. Analysis of patient-specific quality assurance results revealed that 545 (97.67%) planar dosage verification had gamma (3% at 3 mm) values >95%. The online patient set-up verification showed translational and rotational deviation within 2 mm and 0.5° in 88-94% and 97% of the cases. Systematic and random error were within 0.90 mm and 1.71 mm in translation and 0.1° and 0.2° in rotation., Conclusion: A change in practice pattern was observed. The findings from our comprehensive critical appraisal add to the growing library of CSI practice and may serve as a reference for inter-institutional comparison., (Copyright © 2022 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.)

Purpose: To compare the late gastrointestinal (GI) and genitourinary toxicities (GU) estimated using multivariable normal tissue complication probability (NTCP) models, between pencil-beam scanning proton beam therapy (PBT) and helical tomotherapy (HT) in patients of high-risk prostate cancers requiring pelvic nodal irradiation (PNI) using moderately hypofractionated regimen., Materials and Methods: Twelve consecutive patients treated with PBT at our center were replanned with HT using the same planning goals. Six late GI and GU toxicity domains (stool frequency, rectal bleeding, fecal incontinence, dysuria, urinary incontinence, and hematuria) were estimated based on the published multivariable NTCP models. The ΔNTCP (difference in absolute NTCP between HT and PBT plans) for each of the toxicity domains was calculated. A one-sample Kolmogorov-Smirnov test was used to analyze distribution of data, and either a paired t test or a Wilcoxon matched-pair signed rank test was used to test statistical significance., Results: Proton beam therapy and HT plans achieved adequate target coverage. Proton beam therapy plans led to significantly better sparing of bladder, rectum, and bowel bag especially in the intermediate range of 15 to 40 Gy, whereas doses to penile bulb and femoral heads were higher with PBT plans. The average ΔNTCP for grade (G)2 rectal bleeding, fecal incontinence, stool frequency, dysuria, urinary incontinence, and G1 hematuria was 12.17%, 1.67%, 2%, 5.83%, 2.42%, and 3.91%, respectively, favoring PBT plans. The average cumulative ΔNTCP for GI and GU toxicities (ΣΔNTCP) was 16.58% and 11.41%, respectively, favoring PBT. Using a model-based selection threshold of any G2 ΔNTCP >10%, 67% (8 patients) would be eligible for PBT., Conclusion: Proton beam therapy plans led to superior sparing of organs at risk compared with HT, which translated to lower NTCP for late moderate GI and GU toxicities in patients of prostate cancer treated with PNI. For two-thirds of our patients, the difference in estimated absolute NTCP values between PBT and HT crossed the accepted threshold for minimal clinically important difference., Competing Interests: Conflicts of Interest: Srinivas Chilukuri, MD, has received a speaker honorarium from Astra Zeneca, maintains a leadership role in Optimus Oncology, and owns stock in Optimus Oncology. The authors have no other conflicts of interest to disclose., (©Copyright 2022 The Author(s).)

We investigated the influence of random spot positioning errors (SPEs) on dosimetric outcomes of robustly optimized intensity-modulated proton therapy (RB-IMPT) plans in craniospinal irradiation (CSI). Six patients with CSI treated using the RB-IMPT technique were selected. An in-house MATLAB code was used to simulate a random SPE of 1 mm in positive, negative, and both directions for 25%, 50%, and 75% of the total spot positions in the nominal plan. The percentage dose variation (ΔD % ) in the six nominal and 54 error-introduced plans was evaluated using standard dose-volume indices, line dose difference, and 3D gamma analysis method. The introduction of a random SPE of 1 mm resulted in a reduction in D 99% , D 98% , and D 95% of both CTVs and PTVs by < 2% compared with the corresponding nominal plans. However, this leads to an increase in D 1% of the lens by up to 16.9%. The line dose in the junction region showed ΔD %  < 2% for the brain and upper spine and < 4% for the upper and lower spine. The 3D gamma values for 3% at 3 mm and 2% at 2 mm were above 99% and 95%, respectively, in all 54 error-introduced plans. The worst decrease in gamma values was observed for 1% at 1 mm, with values ranging from 64 to 78% for all types of SPE. The RB-IMPT plan for CSI investigated in this study is robust enough for target coverage, even if there are random SPEs of 1 mm. However, this leads to an increase in the dose to the critical organ located close to the target., (© 2021. Japanese Society of Radiological Technology and Japan Society of Medical Physics.)

Objective: To study dosimetric impact of random spot positioning errors on the clinical pencil beam scanning proton therapy plans., Methods and Materials: IMPT plans of 10 patients who underwent proton therapy for tumors in brain or pelvic regions representing small and large volumes, respectively, were included in the study. Spot positioning errors of 1 mm, -1 mm or ±1 mm were introduced in these clinical plans by modifying the geometrical co-ordinates of proton spots using a script in the MATLAB programming environment. Positioning errors were simulated to certain numbers of (20%, 40%, 60%, 80%) randomly chosen spots in each layer of these treatment plans. Treatment plans with simulated errors were then imported back to the Raystation (Version 7) treatment planning system and the resultant dose distribution was calculated using Monte-Carlo dose calculation algorithm.Dosimetric plan evaluation parameters for target and critical organs of nominal treatment plans delivered for clinical treatments were compared with that of positioning error simulated treatment plans. For targets, D95% and D2% were used for the analysis. Dose received by optic nerve, chiasm, brainstem, rectum, sigmoid, and bowel were analyzed using relevant plan evaluation parameters depending on the critical structure. In case of intracranial lesions, the dose received by 0.03 cm 3 volume (D 0.03 cm3 ) was analyzed for optic nerve, chiasm and brainstem. In rectum, the volume of it receiving a dose of 65 Gy(RBE) (V65) and 40 Gy(RBE) (V40) were compared between the nominal and error introduced plans. Similarly, V65 and V63 were analyzed for Sigmoid and V50 and V15 were analyzed for bowel., Results: The maximum dose variation in PTV D 95% (1.88 %) was observed in a brain plan in which the target volume was the smallest (2.7 cm 3 ) among all 10 plans included in the study. This variation in D 95% drops down to 0.3% for a sacral chordoma plan in which the PTV volume is significantly higher at 672 cm 3 . The maximum difference in OARs in terms of absolute dose (D 0.03 cm3 ) was found in left optic nerve (9.81%) and the minimum difference was observed in brainstem (2.48%). Overall, the magnitude of dose errors in chordoma plans were less significant in comparison to brain plans., Conclusion: The dosimetric impact of different error scenarios in spot positioning becomes more prominent for treatment plans involving smaller target volume compared to plans involving larger target volumes., Advances in Knowledge: Provides information on the dosimetric impact of various possible spot positioning errors and its dependence on the tumor volume in intensity modulated proton therapy.

Aim: A novel hybrid three-dimensional (3D) dose reconstruction method, based on planar dose measured at a single shallower depth, was developed for use as patient-specific quality assurance (PSQA) of intensity modulated proton therapy (IMPT) plans. The accuracy, robustness and sensitivity of the presented method were validated for multiple IMPT plans of varying complexities., Methods and Materials: An in-house MATLAB program was developed to reconstruct 3D dose distribution from the planar dose (GyRBE) measured at 3 g cm -2 depth in water or solid phantom using a MatriXX PT ion chamber array. The presented method was validated extensively for 11 single-field optimization (SFO) and multi-field optimization (MFO) plans on Proteus Plus. A total of 47 reconstructed planar doses at different depths were compared against the corresponding RayStation treatment planning system (TPS) and MatriXX PT measurement using a gamma passing rate (γ%) evaluated for 3%/3 mm. The robustness of the reconstruction method with respect to depth, energy layers, field dimensions and complexities in the spot intensity map (SIM) were analysed and compared against the standard PSQA. The sensitivity of the reconstruction method was tested for plans with intentional errors., Results: The presented reconstruction method showed excellent agreement (mean γ% > 98%) and robustness with both TPS-calculated and measured dose planes at all depths (2.97-30 g cm -2 ), energy layers (82.1-225.5 MeV), field dimensions, target volume (17.7-1000 cm 3 ) and SIMs from both SFO and MFO plans. In comparison to the overall mean ± SD γ% from standard PSQA, the reconstruction method showed reductions in mean γ% within 1% for both standard cubes and clinical plans. The reconstruction method was sensitive enough to detect intentional spot positional errors in a selected energy layer of a plan., Conclusion: The presented hybrid reconstruction method is sufficiently accurate, robust and sensitive to estimate planar dose at any user-defined depth. It simplifies the measurement setup and eliminates multiple depth measurements.

Objectives: To measure leakage ambient dose equivalent H*(10) from stray secondary neutron and photon radiation around proton therapy (PT) facility and evaluate adequacy of shielding design., Methods and Materials: H*(10) measurement were carried out at 149 locations around cyclotron vault (CV), beam transport system (BTS) and first treatment room (GTR3) of a multiroom PT facility using WENDI-II and SmartIon survey meter. Measurement were performed under extreme case scenarios wherein maximum secondary neutrons and photons were produced around CV, BTS and GTR3 by stopping 230MeV proton of 300nA on beam degrader, end of BTS and isocenter of GTR3. Weekly time average dose rate (TADR) were calculated from H*(10) value measured at selective hot spots by irradiating actual treatment plans of mix clinical sites., Results: The maximum total H*(10) were within 2 µSv/hr around CV, 5 µSv/hr around outer wall of BTS which increases up to 62 µSv/hr at the end of inside BTS corridor. Maximum H*(10) of 20.8 µSv/hr in treatment control console (P125), 23.4 µSv/hr behind the common wall between GTR3 and GTR2 (P132) and 25.7 µSv/hr above isocenter (P99) were observed around GTR3. Reduction of beam current from 6 to 3 nA and 1 nA at nozzle exit lead to decrease in total H*(10) at P125 from 20.8 to 11.35 and 4.62 µSv/hr. In comparison to extreme case scenario, H*(10) value at P125, P132 and P99 from clinically relevant irradiation parameters were reduce by a factor ranging from 8.6 for high range cube to 46.4 for brain clinical plan. The maximum weekly TADR per fraction was highest for large volume, sacral chordoma patient at 8.5 µSv/hr compare to 0.3 µSv/hr for brain patient. The calculated weekly TADR for 30 mix clinical cases and 15 fractions of 1 L cube resulted total weekly TADR of 83-84 µSv/hr at P125, P132 and P99. The maximum annual dose level at these hot spots were estimated at 4.37 mSv/Yr., Conclusion: We have carried out an extensive measurement of H*(10) under different conditions. The shielding thickness of our PT facility is adequate to limit the dose to occupational worker and general public within the permissible stipulated limit. The data reported here can bridge the knowledge gap in ambient dose around PT facility and can also be used as a reference for any new and existing proton facility for intercomparison and validation., Advances in Knowledge: First extensive investigation of neutron and photon H*(10) around PT facility and can bridge the knowledge gap on ambient dose.

Purpose: Trauma is an important cause of visual loss in children and may affect their quality of life. Prevention and legislation can reduce the incidence of trauma, and appropriate and timely treatment can improve prognosis. We aimed to describe incidence of eye injuries in children and the adherence to national and local management guidelines., Methods: Retrospective service evaluation at a tertiary hospital (Moorfields Eye Hospital, London, UK) which operates a dedicated children's eye casualty. The electronic patient administration system and electronic patient record system (Openeyes) were used to identify children who presented with eye injuries between January 2015 and December 2015., Results: Of 2397 first-time attendances to our children's casualty, 508 were for injuries (estimated incidence 21.1%, 95% confidence interval: 19.5%-22.7%). Mean age at presentation was 7.51 (standard deviation: 7.97) years; boys were more commonly affected than girls (69%). The most common injury was corneal abrasion, followed by blunt and chemical injury; severe injuries such as penetrating trauma were rare. Injuries were sustained mostly during play or sports. Two children sustained permanent loss of vision in the affected eye., Conclusion: Our findings are comparable to other published reports. Adherence to management guidelines is high, but documentation of advice given to families can be improved. Regular training of staff and collaboration with organisations outside the hospital can increase awareness of eye injuries in children.

Aim: This study aimed at evaluating the efficacy of treatment planning system (TPS)-based heterogeneity correction for two- and three-dimensional (2D and 3D) electronic portal imaging device (EPID)-based pretreatment dose verification. An experiment was conducted on the EPID back-projection technique and intensity-modulated radiotherapy (IMRT)., Materials and Methods: Treatment plans were delivered in EPID without a patient to obtain the fluence pattern (F EPID ). A heterogeneity correction plane (F het ) for an open beam of 30 cm × 30 cm was extracted from the TPS. The heterogeneity-corrected measured fluence is developed by matrix element multiplication (F Resultant = F EPID × F het ). Further planes were summed to develop a 3D dose distribution and exported to the TPS. Dose verifications for 2D and 3D were carried out with the corresponding TPS values using 2D gamma analysis (ɣ) and dose volume histogram (DVH) comparison, respectively. Totally, 33 patients (17 head-neck and 16 thorax cases) were evaluated in this study., Results: The head-neck and thorax plans show a 3-mm-distance to agreement (DTA) 3% DD gamma passing of 96.3% ± 2.0% and 95.4% ± 1.8% points, respectively, between F TPS and F Resultant . The comparison of the uncorrected measured fluence (F EPID ) with F TPS reveals a gamma passing of 82.2% ± 7.3% and 80.4% ± 8.6% for head-neck and thorax cases, respectively. A total of 87 out of the 102 head-neck and thorax beams exhibit a planner gamma passing of 97.6% ± 2.1%. In the 3D-DVH comparison of thorax and head-neck cases, D5% for planning target volume were -0.5% ± 2.2% and -2.1% ± 3.5%, respectively; D95% varies as 1.0% ± 2.7% and 1.4% ± 1.1% between TPS calculated and heterogeneity-corrected-EPID-based dose reconstruction., Conclusion: The novel TPS-based heterogeneity correction can improve the 2D and 3D EPID-based back projection technique. Structures with large heterogeneities can also be handled using the proposed technique., Competing Interests: There are no conflicts of interest., (Copyright: © 2019 Journal of Medical Physics.)

Water is treated as radiological equivalent to human tissue. While this seems justified, there is neither mathematical proof nor sufficient experimental evidence that a water phantom can be treated as equivalent to human tissue. The aim of this work is to simulate and validate a water phantom that is tissue equivalent in terms of the dosimetric characteristics of both water and human tissue Dynamic, intensity-modulated radiotherapy plans for two head and neck, one brain, one pelvis, and three lung/mediastinum cases were chosen for this study. Using a treatment planning system (TPS) (Eclipse, Varian Medical System, Polo Alto, CA, USA) and Anisotropic Analytic Algorithm in a grid resolution of 5 mm × 5 mm, a patient-equivalent water phantom was calculated from all rays in the isocentric plane as an array of water equivalent depths (d WE ). These rays were plotted versus isocentric separation and ray-tracing direction. Planar doses were compared between the isocentric plane in the patient computed tomography and the water equivalent phantom using gamma criteria of 2%-2 mm and 3%-3 mm. Except in one lung case, >95% gamma agreement was seen when using 3%-3 mm and >90% pass rate was seen when using 2%-2 mm. For head and neck cases, gamma-fail was restricted to the periphery. For mediastinum cases, gamma-fail was restricted to the lungs. This study demonstrates that a heterogeneous patient can be converted to a water phantom with comparable dosimetric characteristics and disagreements restricted to the lung area for both modulated and open beams. Potential sources of error include the d WE calculation and TPS dose computation., Competing Interests: There are no conflicts of interest.

A six-year-old boy with high-grade fever and abdominal pain in the epigastric region was examined with ultrasonogram of the abdomen. Hematology-cell analysis, serology (Widal test), urine analysis, and blood cultures were also performed. The ultrasonogram was helpful for the identification of multiple organ involvement with Salmonella typhi. The results revealed mild hepatosplenomegaly, minimal ascitis, and mesenteric lympoadenopathy. Hematological analysis showed a white blood count of 6,300 cells mL-1; a red blood cell count of 4.54 million/cu mm. The erythrocyte sedimentation rate (ESR) was 24 mm/1 hr; hemoglobin level of 11.5 g/dl; and a platelet count of 206,000 cells/mL. The patient's serum was agglutinated with lipopolysaccharide (TO), the titre value was 1:320 dilution, and flagellar antigen (TH) titre was 1:640. The patient was diagnosed with typhoid fever. Ceftriaxone was given intravenously for five days and the patient fully recovered.

We evaluated the conservation attitudes of the local villagers living adjacent to the Kalakad-Mundanthurai Tiger Reserve in southern India 6 years after implementation of a World Bank funded eco-development project. We assessed attitudes towards three facets of conservation: the tiger, an emblematic species signifying India's commitment to wildlife conservation; the forest, a principle source of fuel-wood and other products; and the Forest Department, which manages the forest. More specifically we predicted that (i) attitudes would be an effective predictor of resource use interest in the forest and (ii) benefits obtained from the EDP would create more favorable attitudes towards conservation and the protected area employees. Twelve villages located within 3 km from the reserve boundary were chosen and 2-3% of the households interviewed with regard to their attitudes towards these three facets of conservation, their household resource use patterns, wealth, sex, age and length of residency. We found significant associations between wealth, sex, age and both tiger and forest conservation. Providing benefits has not changed the underlying attitudes of the communities. The poorer sections of society, whether receiving benefits or not, tended to support tiger conservation because conserving wildlife did not affect their livelihood in any way, whereas both the rich and poor had misgivings about forest conservation due to dependency on forest products. We conclude that the eco-development project has not effectively addressed the most important of the local concerns.