bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance of region‐of‐influence approach of frequency analysis of extreme rainfall in monsoon climate conditions
Authors: Das Samiran 
Published: March 2017

ABSTRACTThis study investigates the applicability of the region‐of‐influence (ROI) approach of frequency analysis of extreme rainfall in a monsoon‐dominated country and to find the most appropriate scheme of the method. Seven differentROIpooling schemes are examined which differ in their similarly distance measure containing a range of different site descriptors (also known as pooling variables). The site descriptors also include average annual monsoon rainfall (AAMR) which is introduced to assess its suitability in this climatic condition. TheROIschemes are evaluated against traditional regional as well as at‐site frequency analysis. The performance of the selected scheme in terms of homogeneity and frequency behaviour is also assessed. In order to determine the performance, the study uses annual maximum rainfall data of 1‐day duration at 34 stations in Bangladesh, which has a tropical monsoon climate. It is found that theROImethod of any variants is superior to the traditional geographical approach of regional analysis as well as to the at‐site analysis. TheAAMRbased pooling scheme has provided the best result among the consideredROIschemes. The pooling groups delineated based onAAMRhas also passed the homogeneity test and conveyed a desirable frequency behaviour. All results indicate that theAAMRas a pooling variable, i.e. information about monsoon rainfall, should be accommodated to the estimation of extreme rainfall in a monsoon‐dominated region.
Outcomes of HPV‐related nasal squamous cell carcinoma
Authors: Chowdhury Naweed , Alvi Sameer , Kimura Kyle , Tawfik Ossama , Manna Pradip , Beahm David , Robinson Ann , Kerley Spencer , Hoover Larry 
Published: March 2017

BackgroundHuman papilloma virus (HPV) infection has been shown to play an integral role in the development and prognosis of various head and neck cancers. Generational changes in sexual behavior may have led to an increased incidence of positivity in recent years. HPV positivity in both benign and malignant lesions of the sinonasal cavities has been shown in previous studies (estimates range from 20%–30% for malignancy). We intend to investigate if HPV positivity affected survival outcomes in our patient cohort.Methods/MaterialsTwenty‐six patients diagnosed pathologically for sinonasal squamous cell carcinoma (SCC) with available archived biopsy specimens were retrospectively analyzed to obtain HPV status using a real‐time, multiplex polymerase chain reaction assay that detects and quantifies 15 known high‐risk HPV types. Demographic information was collected, and survival analyses were performed using the Kaplan‐Meier estimation.ResultsSixteen of 26 (62%) SCC tumors in the patient cohort were positive for HPV DNA. HPV types 16 and 18 were the most common (n = 8 and 2, respectively), although a wide range of HPV types across the 15 tested were positive. Survival analyses showed a statistically significant survival advantage (median survival of 12 vs. 54 months) when accounting for HPV positivity using log‐rank testing (P < 0.003).ConclusionHPV positivity appears to be present in a significant proportion of squamous cell carcinoma cases of the nasal cavity. In our limited patient population there does appear to be a survival advantage to HPV positivity. Further prospective, multi‐institutional trials with standardized treatment protocols are needed to elucidate the true impact of HPV positivity in this subset of head and neck cancers.Level of Evidence4. Laryngoscope, 127:1600–1603, 2017
Positron emission tomography/computed tomography after primary transoral robotic surgery for oropharyngeal squamous cell carcinoma
Authors: Hobelmann Kealan , Luginbuhl Adam , Bar‐Ad Voichita , Keane William , Curry Joseph , Cognetti David 
Published: March 2017

Objectives/HypothesisTo assess the first post‐treatment positron emission tomography/computed tomography (PET/CT) in prediction of disease‐free survival after primary transoral robotic surgery (TORS) for oropharyngeal squamous cell carcinoma (OPSCC) with or without adjuvant chemoradiation.Study DesignRetrospective review.MethodsNinety‐five patients with OPSCC treated with primary TORS from 2010 to 2014 at a single tertiary academic center were evaluated with PET/CT. Imaging was performed between 2 and 7 months after completing all treatment. Radiology findings were categorized as 1) negative, noting either complete resolution of foci without evidence of disease or anatomical changes likely attributed to treatment; 2) equivocal, noting equal likelihood of malignancy versus treatment‐related changes; or 3) positive, noting either findings concerning for malignancy or new hyperactivity not attributed to treatment‐related changes. The median follow‐up time was 31 months (range, 23–63 months). Recurrence was defined as biopsy‐proven invasive malignancy or clinical suspicion sufficient to initiate treatment occurring within 3 years of the completion of all treatment.ResultsOf 95 total patients with at least 2 years of follow‐up records, 26 had positive post‐treatment PET/CT results, with five experiencing actual recurrences. Of 69 patients with negative post‐treatment PET/CT results, none experienced recurrences. These results indicate a sensitivity of 100%, specificity of 77%, positive predictive value of 19%, and negative predictive value of 100%.ConclusionsA majority of TORS patients (73%) will have a negative first post‐treatment PET/CT. A single negative post‐treatment PET/CT is strongly correlated with 2‐year disease‐free survival in patients treated with primary TORS and may warrant decreased surveillance imaging.Level of Evidence4 Laryngoscope, 127:2050–2056, 2017
Scoping review of pediatric tonsillectomy quality of life assessment instruments
Authors: Kao Stephen Shih‐Teng , Peters Micah D. J. , Dharmawardana Nuwan , Stew Benjamin , Ooi Eng Hooi 
Published: March 2017

Objectives/HypothesisSleep‐disordered breathing or recurrent tonsillitis have detrimental effects on the child's physical health and quality of life. Tonsillectomy is commonly performed to treat these common conditions and improve the child's quality of life. This scoping review aims to present a comprehensive and descriptive analysis of quality of life questionnaires as a resource for clinicians and researchers when deciding which tool to use when assessing the quality of life effects after tonsillectomy.Study DesignA comprehensive search strategy was undertaken across MEDLINE (PubMed), CINAHL, Embase, and Cochrane CENTRAL.MethodsQuality of life questionnaires utilized in studies investigating pediatric patients undergoing tonsillectomy for chronic tonsillitis or sleep‐disordered breathing were included. Methodological quality and data extraction were conducted as per Joanna Briggs Institute methodology.ResultsTen questionnaires were identified, consisting of six generic and four disease‐specific instruments. The Pediatric Quality of Life Inventory was the most commonly utilized generic questionnaire. The Obstructive Sleep Apnea‐18 was the most commonly utilized disease‐specific questionnaire.ConclusionsThis review identified a range of generic and disease‐specific quality of life questionnaires utilized in pediatric patients who have undergone tonsillectomy with or without adenoidectomy for sleep‐disordered breathing or chronic tonsillitis. Important aspects of each questionnaire have been summarized to aid researchers and clinicians in choosing the appropriate questionnaire when evaluating the quality of life effects of tonsillectomy.Level of EvidenceNA Laryngoscope, 127:2399–2406, 2017
Silent sinus syndrome after facial trauma: A case report and literature review
Authors: Araslanova Rakhna , Allen Larry , Rotenberg Brian W. , Sowerby Leigh J. 
Published: March 2017

ObjectiveThe accepted definition of silent sinus syndrome (SSS) excludes posttraumatic cases. To challenge current exclusion criteria of antecedent facial trauma, we have identified all published cases of posttraumatic SSS in English literature, including a new representative case from our institution.Data SourcesMEDLINE, EMBASE, and Scopus databases.Review MethodsAll case reports and case series published in English literature from 1964 through August 2016 were sequentially identified. Authors of cases with missing information were contacted for completion.ResultsThirteen documented cases of posttraumatic SSS were identified through the literature review. An additional case from our institution was presented, bringing the total reported case count to 14. Time from initial trauma to presentation ranged from 2 months to 32 years, with a median duration of 6 months. Endoscopic sinus surgery (ESS) with either concurrent or staged orbital floor implant repair was used to treat posttraumatic SSS in 64% of reported cases. Three patients had ESS alone, with one case showing postoperative improvement in enophthalmos.ConclusionRecent emergence of case reports of SSS postorbital and facial trauma challenge the current exclusion criteria of precedent facial trauma. Posttraumatic SSS is rare, but the availability of cross‐sectional imaging pre‐ and postdevelopment of SSS makes a strong case for a causal relationship. Laryngoscope, 127:1520–1524, 2017
Definitive chemoradiotherapy with carboplatin for squamous cell carcinoma of the head and neck
Authors: Nagasaka Misako , Zaki Mark , Issa Majd , Kim Harold , Abrams Judith , Sukari Ammar 
Published: March 2017

ObjectiveDefinitive concurrent chemoradiotherapy (CRT) is considered the standard of care for organ preservation and is the only potentially curative therapy for surgically unresectable patients with stage III to IVb locally advanced squamous cell carcinoma of the head and neck. In patients with high risks for adverse events utilizing cisplatin, carboplatin has been empirically substituted. The objective of this study was to estimate the locoregional control rate, progression‐free survival, overall survival, and adverse events in locally advanced squamous cell carcinoma of the head and neck patients treated with CRT utilizing carboplatin.Study DesignA retrospective single‐arm analysis.MethodsData on consecutive patients who fit the eligibility criteria were collected. Eligible patients were treated with 70 Gy of radiation therapy and at least two cycles of carboplatin (area of curve [AUC] of 5 between January 2007 to December 2013.ResultsFifty‐four patients were identified. Overall locoregional control rate was 50% (95% confidence interval [CI] 37%–63%). Median progression‐free and overall survival were 21 (CI 11–33) and 40 (CI 33–NA) months, respectively. One‐, 3‐, and 5‐year overall survival were 81% (CI 67%–89%), 59% (CI 41%–73%), and 42% (CI 22%–61%), respectively. Stage III/IVa patients (n = 45) had a median survival of 62 (CI 37–NA months) and 3 years of 71% (CI 53%–84%), whereas stage IVb (n = 9) had a median survival of 31 (CI 4–NA) months and none survived to 3 years.ConclusionDefinitive CRT with carboplatin for locally advanced squamous cell carcinoma of the head and neck was well tolerated and demonstrated comparable results to CRT with cisplatin.Level of Evidence4. Laryngoscope, 127:2260–2264, 2017
Expanded transcanal transpromontorial approach to the internal auditory canal: Pilot clinical experience
Authors: Presutti Livio , Alicandri‐Ciufelli Matteo , Bonali Marco , Rubini Alessia , Pavesi Giacomo , Feletti Alberto , Masotto Barbara , Anschuetz Lukas , Marchioni Daniele 
Published: March 2017

Objectives/HypothesisThe aim of this study was to describe and evaluate the feasibility of an expanded transcanal transpromontorial approach, developed from the exclusive endoscopic transcanal transpromontorial approach.Study DesignRetrospective case series.MethodsRetrospective chart review of 10 patients operated by an expanded transcanal transpromontorial approach in two tertiary referral centers (University Hospital of Modena, Italy and University Hospital of Verona, Italy). Data from charts and video documentation were collected and analyzed.ResultsBetween April 2015 and January 2016, 10 patients underwent an expanded transcanal transpromontorial approach for vestibular schwannoma Koos stage I or II and were enrolled in the study. The size of the tumors ranged from 7 to 19 mm in maximum diameter. A gross total resection was achieved in all cases. One subject experienced postoperative cerebrospinal fluid otorhinorrhea and three subjects experienced temporary postoperative facial weakness, all of which completely resolved. The mean follow‐up was 5 months.ConclusionsThe expanded transcanal transpromontorial approach allowed bimanual dissection using a microscopic technique for the treatment of pathologies of the internal auditory canal and cerebellopontine angle. This novel approach resulted in minimal morbidity and comparable facial nerve preservation rates to the traditional approaches to the internal auditory canal. The expanded transpromontorial approach to the internal auditory canal holds promise for addressing pathology in this region of the temporal bone from the external auditory canal.Level of Evidence4. Laryngoscope, 127:2608–2614, 2017
Optical levitation of nanodiamonds by doughnut beams in vacuum
Authors: Zhou Lei‐Ming , Xiao Ke‐Wen , Chen Jun , Zhao Nan 
Published: March 2017

AbstractOptically levitated nanodiamonds with nitrogen‐vacancy centers promise a high‐quality hybrid spin‐optomechanical system. However, the trapped nanodiamond absorbs energy from laser beams and causes thermal damage in vacuum. It is proposed here to solve the problem by trapping a composite particle (a nanodiamond core coated with a less absorptive silica shell) at the center of strongly focused doughnut‐shaped laser beams. Systematical study on the trapping stability, heat absorption, and oscillation frequency concludes that the azimuthally polarized Gaussian beam and the linearly polarized Laguerre‐Gaussian beam LG03 are the optimal choices. With our proposal, particles with strong absorption coefficients can be trapped without obvious heating and, thus, the spin‐optomechanical system based on levitated nanodiamonds are made possible in high vacuum with the present experimental techniques.
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A radiobiological model of reoxygenation and fractionation effects
Authors: Guerrero Mariana , Carlson David J. 
Published: March 2017

PurposeThe purpose of this study was to develop a radiobiological model of reoxygenation that fulfills the following goals: (a) Quantify the reoxygenation effect for different fractionations (b) Model the hypoxic fraction in tumors as a function of the number of radiation treatments. (c) Develop a simple analytical expression for a reoxygenation term in biological effect calculations.MethodThe model considers tumor cells in two compartments: an aerobic (or normoxic) population of cells and a hypoxic population including cells under a range of reduced oxygen concentrations. The surviving fraction is predicted using the linear‐quadratic (LQ) model. A hypoxia reduction factor (HRF) is used to quantify reductions in radiosensitivity parameters αA and βA as cellular oxygen concentration decreases. The HRF is defined as the ratio of the dose at a specific level of hypoxia to the dose under fully aerobic conditions to achieve equal cell killing. The model assumes that a fraction of the hypoxic cells (Δ) moves from the hypoxic to the aerobic compartment after each daily fraction. As an example, we compare the effect of reoxygenation on biological response for a standard dose fractionation for nonsmall cell lung cancer (NSCLC) (d = 2 Gy, n = 33) to typical fractionations for stereotactic body radiotherapy (SBRT) and other nonstandard fractionations.ResultsThe reoxygenation effect is parameterized for biological effect calculations and an analytic expression for the surviving fraction after n daily treatments is derived. The hypoxic fraction either increases or decreases with n depending on the reoxygenation parameter Δ. For certain combinations of parameters, the biological effect of reoxygenation goes as −(n−1) · ln(1−Δ) providing a simple expression that can be introduced in biologically effective dose (BED) calculations. The model is used to compare fractionation schedules and quantitatively interpret results from molecular imaging studies of hypoxia. Based on the comparison of conventional fractionation and hypo‐ and hyper‐fractionation for NSCLC, the value of Δ is estimated to be between 0.1 and 0.2 assuming plausible radiobiological parameters from the literature. This value is consistent with the preliminary analysis of the molecular imaging studies.ConclusionsA novel radiobiological model was developed that can be used to evaluate the effect of reoxygenation in fractionated radiotherapy.
Two‐compartment modeling of tissue microcirculation revisited
Authors: Brix Gunnar , Salehi Ravesh Mona , Griebel Jürgen 
Published: March 2017

PurposeConventional two‐compartment modeling of tissue microcirculation is used for tracer kinetic analysis of dynamic contrast‐enhanced (DCE) computed tomography or magnetic resonance imaging studies although it is well‐known that the underlying assumption of an instantaneous mixing of the administered contrast agent (CA) in capillaries is far from being realistic. It was thus the aim of the present study to provide theoretical and computational evidence in favor of a conceptually alternative modeling approach that makes it possible to characterize the bias inherent to compartment modeling and, moreover, to approximately correct for it.MethodsStarting from a two‐region distributed‐parameter model that accounts for spatial gradients in CA concentrations within blood‐tissue exchange units, a modified lumped two‐compartment exchange model was derived. It has the same analytical structure as the conventional two‐compartment model, but indicates that the apparent blood flow identifiable from measured DCE data is substantially overestimated, whereas the three other model parameters (i.e., the permeability‐surface area product as well as the volume fractions of the plasma and interstitial distribution space) are unbiased. Furthermore, a simple formula was derived to approximately compute a bias‐corrected flow from the estimates of the apparent flow and permeability‐surface area product obtained by model fitting. To evaluate the accuracy of the proposed modeling and bias correction method, representative noise‐free DCE curves were analyzed. They were simulated for 36 microcirculation and four input scenarios by an axially distributed reference model.ResultsAs analytically proven, the considered two‐compartment exchange model is structurally identifiable from tissue residue data. The apparent flow values estimated for the 144 simulated tissue/input scenarios were considerably biased. After bias‐correction, the deviations between estimated and actual parameter values were (11.2 ± 6.4) % (vs. (105 ± 21) % without correction) for the flow, (3.6 ± 6.1) % for the permeability‐surface area product, (5.8 ± 4.9) % for the vascular volume and (2.5 ± 4.1) % for the interstitial volume; with individual deviations of more than 20% being the exception and just marginal. Increasing the duration of CA administration only had a statistically significant but opposite effect on the accuracy of the estimated flow (declined) and intravascular volume (improved).ConclusionsPhysiologically well‐defined tissue parameters are structurally identifiable and accurately estimable from DCE data by the conceptually modified two‐compartment model in combination with the bias correction. The accuracy of the bias‐corrected flow is nearly comparable to that of the three other (theoretically unbiased) model parameters. As compared to conventional two‐compartment modeling, this feature constitutes a major advantage for tracer kinetic analysis of both preclinical and clinical DCE imaging studies.
Translation and validation of the 15‐item Myasthenia Gravis Quality of life scale in Dutch
Authors: Strijbos Ellen , Gärtner Fania R. , Verschuuren Jan J. 
Published: March 2017

ABSTRACTIntroduction: The 15‐item Myasthenia Gravis Quality of Life (MG‐QOL15) scale has been developed to assess the health‐related quality of life of patients with myasthenia gravis (MG). The aim of this study was to translate the original English version into Dutch and to test the test–retest reliability and construct validity. Methods: Fifty patients with MG were included. Test–retest reliability and internal consistency were assessed using the intraclass correlation coefficient (ICC) and the Cronbach α. Construct validity was assessed by testing 5 predefined hypotheses. Results: A good test–retest reliability was confirmed with an ICC of 0.866. The Cronbach α was 0.93. The predefined hypotheses were confirmed in 80% of cases, which points to good construct validity. Discussion: The Dutch MG‐QOL15 has good test–retest reliability and good construct validity. It can be used for research in a Dutch‐speaking population. It is also suitable for monitoring individual patients in clinical practice. Muscle Nerve 57: 206–211, 2018
Accuracy in the quantification of chemical exchange saturation transfer (CEST) and relayed nuclear Overhauser enhancement (rNOE) saturation transfer effects
Authors: Zhang Xiao‐Yong , Wang Feng , Li Hua , Xu Junzhong , Gochberg Daniel F. , Gore John C. , Zu Zhongliang 
Published: March 2017

Accurate quantification of chemical exchange saturation transfer (CEST) effects, including dipole–dipole mediated relayed nuclear Overhauser enhancement (rNOE) saturation transfer, is important for applications and studies of molecular concentration and transfer rate (and thereby pH or temperature). Although several quantification methods, such as Lorentzian difference (LD) analysis, multiple‐pool Lorentzian fits, and the three‐point method, have been extensively used in several preclinical and clinical applications, the accuracy of these methods has not been evaluated. Here we simulated multiple‐pool Z spectra containing the pools that contribute to the main CEST and rNOE saturation transfer signals in the brain, numerically fit them using the different methods, and then compared their derived CEST metrics with the known solute concentrations and exchange rates. Our results show that the LD analysis overestimates contributions from amide proton transfer (APT) and intermediate exchanging amine protons; the three‐point method significantly underestimates both APT and rNOE saturation transfer at −3.5 ppm (NOE(−3.5)). The multiple‐pool Lorentzian fit is more accurate than the other two methods, but only at lower irradiation powers (≤1 μT at 9.4 T) within the range of our simulations. At higher irradiation powers, this method is also inaccurate because of the presence of a fast exchanging CEST signal that has a non‐Lorentzian lineshape. Quantitative parameters derived from in vivo images of rodent brain tumor obtained using an irradiation power of 1 μT were also compared. Our results demonstrate that all three quantification methods show similar contrasts between tumor and contralateral normal tissue for both APT and the NOE(−3.5). However, the quantified values of the three methods are significantly different. Our work provides insight into the fitting accuracy obtainable in a complex tissue model and provides guidelines for evaluating other newly developed quantification methods.