Large-scale analysis of structural brain asymmetries during neurodevelopment: Associations with age and sex in 4265 children and adolescents.

Only a small number of studies have assessed structural differences between the two hemispheres during childhood and adolescence. However, the existing findings lack consistency or are restricted to a particular brain region, a specific brain feature, or a relatively narrow age range. Here, we investigated associations between brain asymmetry and age as well as sex in one of the largest pediatric samples to date (n = 4265), aged 1-18 years, scanned at 69 sites participating in the ENIGMA (Enhancing NeuroImaging Genetics through Meta-Analysis) consortium. Our study revealed that significant brain asymmetries already exist in childhood, but their magnitude and direction depend on the brain region examined and the morphometric measurement used (cortical volume or thickness, regional surface area, or subcortical volume). With respect to effects of age, some asymmetries became weaker over time while others became stronger; sometimes they even reversed direction. With respect to sex differences, the total number of regions exhibiting significant asymmetries was larger in females than in males, while the total number of measurements indicating significant asymmetries was larger in males (as we obtained more than one measurement per cortical region). The magnitude of the significant asymmetries was also greater in males. However, effect sizes for both age effects and sex differences were small. Taken together, these findings suggest that cerebral asymmetries are an inherent organizational pattern of the brain that manifests early in life. Overall, brain asymmetry appears to be relatively stable throughout childhood and adolescence, with some differential effects in males and females.

The 40Ar(d,p)41Ar cross section between 3-7 MeV.

To determine the safety of using argon as a deuteron beam stopping material, the  40Ar(d,p)41Ar cross section was measured at average deuteron energies of 3.6 MeV, 5.5 MeV, and 7.0 MeV using an activation method. A 16-MeV deuteron beam produced by Lawrence Berkeley National Laboratory's 88-Inch Cyclotron was degraded to each energy by nickel foils and the front wall of an aluminum gas chamber. The reduced-energy deuterons were used to activate a sample of natAr gas. After each irradiation, the gas chamber's  41Ar activation was measured with a high-purity germanium detector. The cross sections measured were larger than a previous measurement by ∼40%.

Rheumatologic diseases in patients with inborn errors of immunity in the USIDNET registry.

There is a gap in clinical knowledge regarding associations between specific inborn errors of immunity (IEIs) and rheumatologic diseases. This study reports the frequency of rheumatologic conditions in a large cohort of patients with IEI using the USIDNET (United States Immunodeficiency Network) registry. We used the USIDNET registry to conduct the analysis. We included all IEI patients within the registry for whom a diagnosed rheumatologic disease was reported. The total number of patients with IEI in our query was 5058. Among those, 278 (5.49%) patients had a diagnosis of rheumatologic disease. This cohort included 172 (61.8%) female and 106 (38.2%) male patients. Rheumatologic complications were highest in the interferonopathies (66.6%), autoimmune lymphoproliferative syndrome (ALPS) (13.7%), and immunoglobulin G subclass deficiency (IgGSD) (11.11%). Additionally, disease patterns were noted to be different in various IEI disease groups. Inflammatory myopathies were the most common rheumatologic condition in patients with X-linked agammaglobulinemia (1.65%), Sjogren's syndrome was the most common rheumatologic disease reported in ALPS patients (6.85%), and systemic lupus erythematosus was the most common rheumatologic disease in patients with chronic mucocutaneous candidiasis (CMC) (7.41%). Rheumatoid arthritis (RA) report rate was highest in patients with IgGSD (3.70%), specific antibody deficiency (SAD) (3.66%), and ALPS (2.74%). This study reports that rheumatologic diseases are frequently observed in patients with IEI. The frequency of different rheumatologic conditions was variable based on the underlying diagnosis. Clinicians caring for patients with IEI should be vigilant to monitor for rheumatologic complications. Key Points • The rates of reported rheumatologic diseases in the USIDNET registry are different in individual IEIs. • Further studies are needed to guide clinicians for detecting rheumatologic conditions earlier in patients with IEI.

Precision measurement of relative γ-ray intensities from the decay of 61Cu.

A discrepancy, well outside reported uncertainties, has been observed between the accepted and measured values of the intensity ratio of the two strongest γ rays following 61Cu ß+ decay. This discrepancy has significant impact since the natNi(d,x)61Cu reaction has historically been one of only a few IAEA recommendations for use as a deuteron flux monitor and a considerable number of published cross sections measured in ratio to that beam monitor cross section may depend on the choice of either the first or second strongest γ ray in those calculations. To determine the magnitude of this error most precisely, over a hundred separate measurements of the 283 keV to 656 keV γ-ray emission ratio were collected from seven experiments and a variety of detectors and detection geometries. A weighted average of all these measurements indicates an error in the value listed in the Nuclear Data Sheets of 11% in either the primary or second-highest intensity γ ray of 61Cu, potentially introducing an 11% error in 61Cu production cross section measurements, cross sections using nickel activation as a deuteron beam current monitor, or in dose rates when 61Cu is used in nuclear medicine. General agreement with the Data Sheets with ten other intensity ratios suggests the most probable error is in the secondary (656 keV) emission, which accordingly should be updated from 10.8% to 9.69%.

A guide to architecture for the public health workforce.

BACKGROUND: Public health and environmental challenges facing the world in the 21st century, including the ageing population, increasing urbanisation, rise of non-communicable diseases and climate instability, require an interdisciplinary response. A significant proportion of the population's time is spent indoors, be it at home, school, work or in leisure time; the work of an architect can cover all of these sectors, but their role in health and well-being remains an under explored area. OBJECTIVE: This article examines the architecture profession's potential to contribute to improved health and well-being of the population through healthier buildings and places. METHODOLOGY: This short communication adopts a descriptive approach. First, it maps the remit, skills and influence of the architecture profession and applies this to a well-accepted public health model, the prevention pyramid. Second, it uses themes identified by the Royal Society for Public Health to discuss ways to improve engagement with the architecture profession as part of the wider public health workforce. RESULTS: This article finds that the remit, skills and potential influence of architects places them in a key position to improve the health and well-being of the population. Despite this, there has been relatively little engagement between public health and this profession. Much more attention to date has been on integrating the planning sector with public health. CONCLUSION: Opportunities for improved engagement exist through partnership working, incorporating health into both undergraduate and postgraduate education and continuing professional development training, building the evidence base and developing architecture and health-related policy and legislation.

Seasonal intensification and trends of rogue wave events on the US western seaboard.

Studies of changes in wave climate typically consider trends in sea state statistics, such as the significant wave height. However, the temporal variability of individual rogue waves, which pose a hazard to users of the sea and coastal environment has not been investigated. We use time series of continuous surface elevation over 124-270 months (spanning 1994-2016), from 15 wave buoys along the US western seaboard, to investigate regional trends in significant wave height and individual rogue waves. We find high spatial variability in trends in significant wave height and rogue waves across the region. Rogue wave occurrence displays a mostly decreasing trend, but the relative height - or severity - of the waves is increasing. We also identify seasonal intensification in rogue waves with increased rogue wave occurrence, of higher severity, in the winter than in the summer. Therefore, the common practice of stating a single occurrence likelihood for an ocean basin is not valid. In addition, the buoy data show that the magnitude and significance of trends in significant wave height increases towards higher percentiles, supporting previous findings.

The Interaction of Compliance and Activation on the Force-Length Operating Range and Force Generating Capacity of Skeletal Muscle: A Computational Study using a Guinea Fowl Musculoskeletal Model.

A muscle's performance is influenced by where it operates on its force-length (F-L) curve. Here we explore how activation and tendon compliance interact to influence muscle operating lengths and force-generating capacity. To study this, we built a musculoskeletal model of the lower limb of the guinea fowl and simulated the F-L operating range during fixed-end fixed-posture contractions for 39 actuators under thousands of combinations of activation and posture using three different muscle models: Muscles with non-compliant tendons, muscles with compliant tendons but no activation-dependent shift in optimal fiber length (L0), and muscles with both compliant tendons and activation-dependent shifts in L0. We found that activation-dependent effects altered muscle fiber lengths up to 40% and increased or decreased force capacity by up to 50% during fixed-end contractions. Typically, activation-compliance effects reduce muscle force and are dominated by the effects of tendon compliance at high activations. At low activation, however, activation-dependent shifts in L0 are equally important and can result in relative force changes for low compliance muscles of up to 60%. There are regions of the F-L curve in which muscles are most sensitive to compliance and there are troughs of influence where these factors have little effect. These regions are hard to predict, though, because the magnitude and location of these areas of high and low sensitivity shift with compliance level. In this study we provide a map for when these effects will meaningfully influence force capacity and an example of their contributions to force production during a static task, namely standing.

A Interação de Conformidade e Ativação na Faixa de Operação Força-Comprimento e Capacidade de Geração de Força do Músculo Esquelético: Um Estudo Computacional Usando um Modelo Musculoesquelético de Galinhas-D'angola O desempenho muscular é influenciado por onde ele opera na sua curva de força-comprimento. Aqui, exploramos como a ativação e a conformidade do tendão interagem para influenciar os comprimentos musculares e a capacidade de geração de força. Para estudar isso, construímos um modelo musculoesquelético do membro inferior da galinha-d'angola e simulamos a faixa de operação força-comprimento durante contrações fixas de postura e extremidade para 39 atuadores sob milhares de combinações de ativação e postura usando três modelos musculares diferentes: músculos com tendões não-complacentes, músculos com tendões complacentes, mas sem desvio dependente de ativação no comprimento ideal de fibra (L0), e músculos com tendões complacentes e desvios dependentes de ativação em L0. Descobrimos que os efeitos dependentes da ativação alteraram os comprimentos da fibra muscular em até 40% e aumentaram ou diminuíram a capacidade de força em até 50% durante as contrações de extremidade fixas. Normalmente, os efeitos de ativação e conformidade reduzem a força muscular e são dominados pelos efeitos de complacência do tendão em altas ativações. Em baixa ativação, no entanto, desvios dependentes de ativação em L0 são igualmente importantes e podem resultar em mudanças de força relativas de até 60% para músculos de baixa complacência. Existem regiões da curva de força-comprimento em que os músculos são mais sensíveis à complacência e há baixas de influência onde esses fatores têm pouco efeito. Essas regiões são difíceis de prever porque a magnitude e a localização dessas áreas de alta e baixa sensibilidade mudam com o nível de conformidade. Neste estudo, fornecemos um mapa para quando esses efeitos influenciarão significativamente a capacidade de força e um exemplo de suas contribuições para a produção de forças durante uma tarefa estática, ou seja, em pé. Translated to Portuguese by G. Sobral (gabisobral@gmail.com).

Time-resolved stimulated emission depletion and energy transfer dynamics in two-photon excited EGFP.

Time and polarization-resolved stimulated emission depletion (STED) measurements are used to investigate excited state evolution following the two-photon excitation of enhanced green fluorescent protein (EGFP). We employ a new approach for the accurate STED measurement of the hitherto unmeasured degree of hexadecapolar transition dipole moment alignment α40 present at a given excitation-depletion (pump-dump) pulse separation. Time-resolved polarized fluorescence measurements as a function of pump-dump delay reveal the time evolution of α40 to be considerably more rapid than predicted for isotropic rotational diffusion in EGFP. Additional depolarization by homo-Förster resonance energy transfer is investigated for both α20 (quadrupolar) and α40 transition dipole alignments. These results point to the utility of higher order dipole correlation measurements in the investigation of resonance energy transfer processes.

Polarized two-photon photoselection in EGFP: Theory and experiment.

In this work, we present a complete theoretical description of the excited state order created by two-photon photoselection from an isotropic ground state; this encompasses both the conventionally measured quadrupolar (K = 2) and the "hidden" degree of hexadecapolar (K = 4) transition dipole alignment, their dependence on the two-photon transition tensor and emission transition dipole moment orientation. Linearly and circularly polarized two-photon absorption (TPA) and time-resolved single- and two-photon fluorescence anisotropy measurements are used to determine the structure of the transition tensor in the deprotonated form of enhanced green fluorescent protein. For excitation wavelengths between 800 nm and 900 nm, TPA is best described by a single element, almost completely diagonal, two-dimensional (planar) transition tensor whose principal axis is collinear to that of the single-photon S0 → S1 transition moment. These observations are in accordance with assignments of the near-infrared two-photon absorption band in fluorescent proteins to a vibronically enhanced S0 → S1 transition.

Changing prevalence and treatment outcomes of patients with p16 human papillomavirus related oropharyngeal squamous cell carcinoma in New Zealand.

There has, to our knowledge, been no previous report of changes in the prevalence and outcomes of treatment of HPV-positive (+) oropharyngeal squamous cell carcinoma (SCC) in New Zealand. We identified all affected patients in the greater Wellington region between 1 January 1994 and 30 November 2014 from the New Zealand Cancer Registry. Their personal details, characteristics of their tumours, treatment, complications, and outcomes were collected retrospectively from their casenotes and the New Zealand Death Registry, followed by p16 immunohistochemical staining. Of the 161 patients included, 131 (81%) were men. p16 immunohistochemical staining was done routinely in 13 patients during investigations, and retrospectively for 135 patients. The proportion of p16+ oropharyngeal SCC increased from 24% during 1994-1999, to 76% during 2009-2014 (p<0.001). Oropharyngeal SCC among Europeans was more likely to be p16+ than in non-Europeans (67% compared with 44%, p=0.036). Patients with p16+ disease were younger (mean (SD) 56 (10) compared with 66 (9) years, p<0.01) with fewer coexisting conditions (mean (SD) Charlson Comorbidity Index: 2.45 (0.82) compared with 2.92 (1.16), p=0.01), and less likely to have smoked (57/81(70%) compared with 38/42 (91%) p=0.035), or misused alcohol (12/81 (15%) compared with 14/42 (31%), p=0.042), or both. They were also more likely to have poorly differentiated tumours (30/52 (58%) compared with 9/34 (26%), p=0.019) with nodal metastases (74/85 (87%) compared with 17/30 (57%), p=0.001). Overall 5-year all-cause survival was more favourable for patients with p16+ disease (65/86 (76%) compared with 15/49 (31%), p=0.000). Interestingly, all-cause age at death was younger in p16+ patients (62 (11.1) compared with 71 (11.2) years, p=0.001). The prevalence of p16+ oropharyngeal SCC had tripled in this population between 1994 and 2014, and affected patients have distinct characteristics and outcomes of treatment.

The microbiota in bronchoalveolar lavage from young children with chronic lung disease includes taxa present in both the oropharynx and nasopharynx.

BACKGROUND: Invasive methods requiring general anaesthesia are needed to sample the lung microbiota in young children who do not expectorate. This poses substantial challenges to longitudinal study of paediatric airway microbiota. Non-invasive upper airway sampling is an alternative method for monitoring airway microbiota; however, there are limited data describing the relationship of such results with lung microbiota in young children. In this study, we compared the upper and lower airway microbiota in young children to determine whether non-invasive upper airway sampling procedures provide a reliable measure of either lung microbiota or clinically defined differences. RESULTS: The microbiota in oropharyngeal (OP) swabs, nasopharyngeal (NP) swabs and bronchoalveolar lavage (BAL) from 78 children (median age 2.2 years) with and without lung disease were characterised using 16S rRNA gene sequencing. Permutational multivariate analysis of variance (PERMANOVA) detected significant differences between the microbiota in BAL and those in both OP swabs (p = 0.0001, Pseudo-F = 12.2, df = 1) and NP swabs (p = 0.0001; Pseudo-F = 21.9, df = 1) with the NP and BAL microbiota more different than the OP and BAL, as indicated by a higher Pseudo-F value. The microbiota in combined OP and NP data (upper airways) provided a more comprehensive representation of BAL microbiota, but significant differences between the upper airway and BAL microbiota remained, albeit with a considerably smaller Pseudo-F (PERMANOVA p = 0.0001; Pseudo-F = 4.9, df = 1). Despite this overall difference, paired BAL and upper airway (OP and NP) microbiota were >50 % similar among 69 % of children. Furthermore, canonical analysis of principal coordinates (CAP analysis) detected significant differences between the microbiota from clinically defined groups when analysing either BAL (eigenvalues >0.8; misclassification rate 26.5 %) or the combined OP and NP data (eigenvalues >0.8; misclassification rate 12.2 %). CONCLUSIONS: Upper airway sampling provided an imperfect, but reliable, representation of the BAL microbiota for most children in this study. We recommend inclusion of both OP and NP specimens when non-invasive upper airway sampling is needed to assess airway microbiota in young children who do not expectorate. The results of the CAP analysis suggest lower and upper airway microbiota profiles may differentiate children with chronic suppurative lung disease from those with persistent bacterial bronchitis; however, further research is needed to confirm this observation.

Adherence to guidelines regarding total hip replacement for fractured neck of femur.

Introduction In 2011 the National Institute for Health and Care Excellence (NICE) published guidelines suggesting that clinicians offer total hip replacement (THR) to patients with displaced intracapsular hip fractures who could walk independently outside with no aids or one stick, who are not cognitively impaired and are ASA (American Society of Anesthesiologists) grade ≤2. They also stated that best practice is operating within 36 hours of presentation. This audit aimed to determine whether Scarborough Hospital was following these guidelines and compared the results with the national average. Methods Two years of data (January 2012 - December 2013) were collected retrospectively from Scarborough Hospital's hip fracture database on all patients presenting with an intracapsular hip fracture. Data were analysed to determine whether patients who had a THR fulfilled NICE criteria. Furthermore, patients with hemiarthroplasties who were eligible for THRs were identified. Finally, the time to surgery was calculated to examine whether patients receiving THRs waited longer than patients receiving hemiarthroplasties. Results In 2012, 48.6% of all eligible patients received a THR while in 2013 the figure was 55.9%. These percentages are much higher than the national average. However, 36 (53.7%) of the 67 patients who received a THR did not fulfil all the NICE criteria, mainly owing to high ASA grade. The mean time from presentation to theatre for THR was 8 hours and 37 minutes longer for THR patients than for hemiarthroplasty in 2012. This difference was reduced to 2 hours and 12 minutes in 2013. Conclusions Small general hospitals can meet and even exceed the standards regarding treatment strategies for hip factures. However, there is still room for improvement. Departmental training may be useful in achieving this aim. The anaesthetic team should be involved at the earliest opportunity, to help optimise patients preoperatively and determine whether patients listed for THR with higher ASA grades are suitable for this surgery.

Serum levels of renin, angiotensin-converting enzyme and angiotensin II in patients treated by surgical excision, propranolol and captopril for problematic proliferating infantile haemangioma.

The role of the renin-angiotensin system (RAS) in the biology of infantile haemangioma (IH) and its accelerated involution induced by ß-blockers was first proposed in 2010. This led to the first clinical trial in 2012 using low-dose captopril, an angiotensin-converting enzyme (ACE) inhibitor, demonstrating a similar response in these tumours. This study aimed to compare serial serum levels of the components of the RAS in patients before and after surgical excision, propranolol or captopril treatment for problematic proliferating IH. Patients with problematic proliferating IH underwent measurements of serum levels of plasma renin activity (PRA), ACE and angiotensin II (ATII) before, and 1-2 and 6 months following surgical excision, propranolol or captopril treatment. This study included 27 patients undergoing surgical excision (n = 8), propranolol (n = 11) and captopril (n = 8) treatment. Treatment with either surgical excision or propranolol resulted in significant decrease in the mean levels of PRA. Surgical excision or captopril treatment led to significant decline in the mean levels of ATII. All three treatment modalities had no significant effect on the mean levels of ACE. This study demonstrates the effect of surgical excision, propranolol and captopril treatment in lowering the levels of PRA and ATII, but not ACE, supporting a mechanistic role for the RAS in the biology of IH.

Does the continuation of warfarin change management outcomes in epistaxis patients?

OBJECTIVE: This study aimed to compare management, readmission rates and length of in-patient stay amongst warfarinised and non-warfarinised patients to ascertain future treatment protocols. METHODS: A 12-month retrospective review was conducted of ENT epistaxis admissions. Admission details such as length of in-patient stay, clotting profile and management plan were recorded. Comparisons of management and outcome for warfarinised and non-warfarinised patients were made using the Fisher's exact paired t-test. RESULTS: Of 176 epistaxis patients admitted, 31 per cent were warfarinised, 18 per cent were on another form of anticoagulation or antiplatelet therapy, and 51 per cent were not on any medication that might impose a bleeding risk. The international normalised ratio at admission was high in 13 per cent of warfarinised patients; the remaining patients had therapeutic or sub-therapeutic international normalised ratios and so warfarin was continued. The mean in-patient stay was similar for all cohorts; however, warfarinised patients had a higher readmission rate. CONCLUSION: Warfarinised epistaxis patients may be safely managed without stopping their anticoagulation therapy, provided their international normalised ratio is at therapeutic or sub-therapeutic levels. By continuing regular anticoagulation therapy, warfarinised patients may be discharged without delay.

Respiratory bacterial culture from two sequential bronchoalveolar lavages of the same lobe in children with chronic cough.

Identification of bacteria causing lower-airway infections is important to determine appropriate antimicrobial therapy. Flexible bronchoscopy with bronchoalveolar lavage (BAL) is used to obtain lower-airway specimens in young children. The first lavage (lavage-1) is typically used for bacterial culture. However, no studies in children have compared the detection of cultivable bacteria from sequential lavages of the same lobe. BAL fluid was collected from two sequential lavages of the same lobe in 79 children enrolled in our prospective studies of chronic cough. The respiratory bacteria Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus and Haemophilus parainfluenzae were isolated and identified using standard published methods. H. influenzae was differentiated from Haemophilus haemolyticus using PCR assays. Lower-airway infection was defined as ≥ 104 c.f.u. ml- 1 BAL fluid. We compared cultivable bacteria from lavage-1 with those from the second lavage (lavage-2) using the κ statistic. Lower-airway infections by any pathogen were detected in 46% of first lavages and 39% of second lavages. Detection was similar in both lavages for all pathogens; the κ statistic was 0.7-0.8 for all bacteria except H. parainfluenzae. Of all infections detected in either lavage, 90% were detected in lavage-1 and 78 in lavage-2. However, culture of lavage-2 identified infections that would have been missed in 8% of children, including infections by additional Streptococcus pneumoniae serotypes. Our findings support the continued use of lavage-1 for bacterial culture; however, culture of lavage-2 may yield additional identifications of bacterial pathogens in lower-airway infections.

Lilac and honeysuckle phenology data 1956-2014.

The dataset is comprised of leafing and flowering data collected across the continental United States from 1956 to 2014 for purple common lilac (Syringa vulgaris), a cloned lilac cultivar (S. x chinensis 'Red Rothomagensis') and two cloned honeysuckle cultivars (Lonicera tatarica 'Arnold Red' and L. korolkowii 'Zabeli'). Applications of this observational dataset range from detecting regional weather patterns to understanding the impacts of global climate change on the onset of spring at the national scale. While minor changes in methods have occurred over time, and some documentation is lacking, outlier analyses identified fewer than 3% of records as unusually early or late. Lilac and honeysuckle phenology data have proven robust in both model development and climatic research.

Characterization and implementation of OSL dosimeters for use in evaluating the efficacy of organ-based tube current modulation for CT scans of the face and orbits.

PURPOSE: The purpose of this work was to characterize commercially available optically stimulated luminescent (OSL) dosimeters for general clinical applications and apply the results to the development of a method to evaluate the efficacy of a vendor-specific organ-based tube current modulation application for both phantom and clinical computed tomography (CT) scans of the face and orbits. METHODS: This study consisted of three components: (1) thorough characterization of the dosimeters for CT scans in phantom, including evaluations of depletion, fading, angular dependence, and conversion from counts to absorbed dose; (2) evaluation of the efficacy of using plastic glasses to position the dosimeters over the eyes in both phantom and clinical studies; and (3) preliminary dosimetry measurements made using organ-based tube current modulation in computed tomography dose index (CTDI) and anthropomorphic phantom studies. RESULTS: (1) Depletion effects were found to have a linear relationship with the output of the OSL dosimeters (R(2) = 0.96). Fading was found to affect dosimeter readings during the first two hours following exposure but had no effect during the remaining 60-h period observed. No significant angular dependence was observed for the exposure conditions used in this study (with p-values ranging from 0.9 to 0.26 for all t-tests). Dosimeter counts varied linearly with absorbed dose when measured in the center and 12 o'clock positions of the CTDI phantoms. These linear models of counts versus absorbed dose had overlapping 95% confidence intervals for the intercepts but not for the slopes. (2) When dosimeters were positioned using safety glasses, there was no adverse effect on image quality, and there was no statistically significant difference between this placement and placement of the dosimeters directly on the eyes of the phantom (p = 0.24). (3) When using organ-based tube current modulation, the dose to the lens of the eye was reduced between 19% and 43%, depending on the scan protocol used and the positioning of the phantom. Furthermore, the amount of dose reduction was significantly affected by the vertical position of the phantom, with the largest reduction in dose seen when the phantom was centered in the gantry. CONCLUSIONS: (1) An appropriate correction factor, specific to CT scanning, was developed to account for depletion and fading characteristics of the dosimeters. Additionally, an equation to convert dosimeter counts to absorbed dose was established. (2) The use of plastic safety glasses was validated as an appropriate positioning device when measuring dose to the lens of the eye. (3) The use of organ-based tube current modulation can reduce dose to the lens of the eye during CT scanning. The amount of dose reduction, however, is largely influenced by the positioning of the anatomy in the gantry.

Mouth opening and trismus in patients undergoing curative treatment for head and neck cancer.

This study documents mouth opening and the incidence of and factors contributing to trismus (<35 mm mouth opening), as well as the associated impact on quality of life, following curative treatment for head and neck cancer. Patient demographics, cancer type and location, and treatments were documented. Mouth opening was measured at >6 months after treatment completion. Patients rated the impact of mouth opening on quality of life from 0 (no effect) to 10 (greatest effect). The mean mouth opening in 120 patients was 40.1mm (range 11-65 mm), with trismus occurring in 34 (28.3%) patients. Surgery and radiotherapy, surgery and chemoradiotherapy, and resection and reconstruction were associated with reduced mouth opening. The mean effect of mouth opening on quality of life for those with and without trismus was 3.8 and 1.5, respectively. There was a significant difference between the mean effect on quality of life for patients with and without trismus for those patients who underwent chemoradiotherapy or combined surgery and radiotherapy (4.0 vs. 1.0, and 3.6 vs. 1.6 respectively). Trismus impacts negatively on patient quality of life. Multi-modality treatment is associated with decreased mouth opening, an increased incidence of trismus, and reduced quality of life.