The trials of neuro-oncology clinical research

Glioblastoma (GBM) remains one of the most challenging and intractable of cancers. Despite being the initial focus of the national effort to identify the molecular driver(s) of solid tumors, these data failed to lead to the anticipated subgroup identification that would guide future clinical trials and therapeutics. Thus, the rationale and design of clinical trials for GBM have not changed that much in more than 50 years. If one examines the initial Brain Tumor Study Group trial (#69-01), which demonstrated the effectiveness of radiotherapy, one can see a sample size (303 patients) and endpoint (overall survival) that look frighteningly similar to modern studies of patients with newly diagnosed GBM.¹ In this issue of Neuro-Oncology, Vanderbeek et al examine our current clinical trial processes and how they are failing to advance only convincingly promising agents forward to phase III studies.² They do not suggest that the failure to identify better therapeutics rests solely with our flawed clinical trial system, and they state at the outset that only further scientific research will open new therapeutic avenues likely to be most helpful. However, they do highlight the wastefulness of our current clinical trial efforts—of time, effort, and patients—that ultimately fail to advance our mission toward improved outcomes.

Water: From Pollution to Purification

Nontuberculous mycobacteria in the environment of Hranice Abyss, the world’s deepest flooded cave (Hranice karst, Czech Republic)

Abstract

Nontuberculous mycobacteria (NTM) are widely distributed in the environment. On one hand, they are opportunistic pathogens for humans and animals, and on the other hand, they are effective in biodegradation of some persistent pollutants. Following the recently recorded large abundance of NTM in extreme geothermal environments, the aim of the study was to ascertain the occurrence of NTM in the extreme environment of the water zone of the Hranice Abyss (HA). The HA mineral water is acidic, with large concentrations of free CO₂, and bacterial slimes creating characteristic mucilaginous formations. Both culture and molecular methods were used to compare the mycobacterial diversity across the linked but distinct ecosystems of HA and the adjacent Zbrašov Aragonite Caves (ZAC) with consideration of their pathogenic relevance. Six slowly growing NTM species (M. arupense, M. avium, M. florentinum, M. gordonae, M. intracellulare) and two rapidly growing NTM species (M. mucogenicum, M. sediminis) were identified in the water and in the dry zones at both sites. Proteobacteria were dominant in all the samples from both the HA and the ZAC. The bacterial microbiomes of the HA mineral water and HA slime were similar, but both differed from the microbiome in the ZAC mineral water. Actinobacteria, a phylum containing mycobacteria, was identified in all the samples at low proportional abundance. The majority of the detected NTM species belong among environmental opportunistic pathogens.

ABCA12 mutations in patients with autosomal recessive congenital ichthyosis: evidence of a founder effect in the Spanish population and phenotype-genotype implications

Mutations in ABCA12 can cause various autosomal recessive congenital ichthyoses (ARCI) phenotypes: harlequin ichthyosis (HI), congenital ichthyosiform erythroderma (CIE), and lamellar ichthyosis (LI). The severity of mutations affecting this gene correlateswith the clinical phenotype developed by the patient. Generally, truncating mutations affecting both alleles or deletions in highly conserved areas of the protein cause HI phenotypes. By contrast, missense mutations that impact protein function less severely result in LI or CIE.

Pain, psychiatric comorbidities, and psychosocial stressors associated with Klippel-Trenaunay Syndrome

Klippel-Trenaunay syndrome affects general and mental health, physical function, and quality of life. Pain, complications, and capillary malformation of the hands are associated with a higher risk of psychiatric illness. Patients with Klippel-Trenuanay syndrome should be screened for potential psychosocial sequelae..

Relationship between concentration of rare earth elements in soil and their distribution in plants growing near a frequented road

Abstract

Rare earth elements (REEs) are a group of elements whose concentration in numerous environmental matrices continues to increase; therefore, the use of biological methods for their removal from soil would seem to be a safe and reasonable approach. The aim of this study was to estimate the phytoextraction efficiency and distribution of light and heavy (LREEs and HREEs) rare earth elements by three herbaceous plant species: Artemisia vulgaris L., Taraxacum officinale F.H. Wigg. and Trifolium repens L., growing at a distance of 1, 10, and 25 m from the edge of a frequented road in Poland. The concentration of REEs in soil and plants was highly correlated (r > 0.9300), which indicates the high potential of the studied plant species to phytoextraction of these elements. The largest proportion of REEs was from the group of LREEs, whereas HREEs comprised only an inconsiderable portion of the REEs group. The dominant elements in the group of LREEs were Nd and Ce, while Er was dominant in the HREEs group. Differences in the amounts of these elements influenced the total concentration of LREEs, HREEs, and finally REEs and their quantities which decreased with distance from the road. According to the Friedman rank sum test, significant differences in REEs concentration, mainly between A. vulgaris L., and T. repens L. were observed for plants growing at all three distances from the road. The same relation between A. vulgaris L. and T. officinale was observed. The efficiency of LREEs and REEs phytoextraction in the whole biomass of plants growing at all distances from the road was A. vulgaris L. > T. officinale L. > T. repens L. For HREEs, the same relationship was recorded only for plants growing at the distance 1 m from the road. Bioconcentration factor (BCF) values for LREEs and HREEs were respectively higher and lower than 1 for all studied plant species regardless of the distance from the road. The studied herbaceous plant species were able to effectively phytoextract LREEs only (BCF > 1); therefore, these plants, which are commonly present near roads, could be a useful tool for removing this group of REEs from contaminated soil.

Effect of salinity stress on phenotypic plasticity, yield stability, and signature of stable isotopes of carbon and nitrogen in safflower

Abstract

Salinity is one of the major factors contributing in land degradation, disturbance of soil biology, a structure that leads to unproductive land with low crop yield potential especially in arid and semiarid regions of the world. Appropriate crops with sufficient stress tolerance capacity and non-conventional water resources should have to be managed in a sustainable way to bring these marginal lands under cultivation for future food security. The goal of the present study was to evaluate salinity tolerant potential (0, 7, and 14 dS m⁻¹) of six safflower genotypes that can be adapted to the hyper arid climate of UAE and its marginal soil. Several agro-morphological and physiological traits such as plant dry biomass (PDM), number of branches (BN), number of capitula (CN), seed yield (SY), stable isotope composition of nitrogen (δ¹⁵N) and carbon (δ¹³C), intercellular CO₂ concentration from inside to ambient air (Ci/Ca), intrinsic water use efficiency (iWUE), carbon (C%) and nitrogen (N %), and harvest index (HI) were evaluated as indicative of the functional performance of safflower genotypes under salt stress. Results indicated that salinity significantly affected the seed yield at all levels and varied significantly among genotypes. The BN, PDM, CN, and δ¹³C attributes showed clear differentiation between tolerant and susceptible genotypes. The δ¹³C results indicate that the tolerant genotypes suffer less from stress, may be due to better rooting. Tolerant genotypes showed lower iWUE values but possess higher yield. Safflower genotypes (PI248836 and PI167390) proved to be salt tolerant, stable, and higher seed and biomass yielder. There was no G × E interaction but the genotypes that produce higher yield under control were still best even under salt stress conditions. Although salinity reduced crop yield, some tolerant genotypes demonstrate adaptation and good yield potential under saline marginal environment.

Septal Chondromucosal Grafts in Paralytic Lagophthalmos

The risk of sight-threatening complications related to facial paralysis makes palpebral fissure management a priority. Surgery must take account of and adapt to the clinical signs of paralytic lagophthalmos. This therefore presupposes that a sufficient therapeutic arsenal is available. In this report, we propose a technique for palpebral lengthening (lower and/or upper), reconstructing the posterior lamella using a chondromucosal graft harvested from the nasal septum, combined with anterior lamellar repositioning.

The Narrow-Lumen Jones Tube: A Novel Approach to Dry Eye Following Conjunctivodacryocystorhinostomy

Conjunctivodacryocystorhinostomy with placement of a Jones tube (JT) is the gold standard for upper lacrimal system dysfunction. However, traditional JT have been associated with various complications. In their practice, the authors have encountered challenges with postoperative dry eye in a select group of patients, with recurrence of epiphora following tube occlusion, suggesting a need for decreasing the rate of tear drainage while maintaining a patent JT. To address this issue, the senior author (J.D.N.) introduced a modified JT with a narrow lumen (reduced-flow JT) for patients who experience significant dry eye symptoms after placement of a JT. The authors describe 3 patients who experienced improvement in dry eye symptoms after the placement of reduced-flow JT. Accepted for publication March 28, 2018. Previously presented at American Society of Ophthalmic Plastic and Reconstructive Surgery 2017 Fall Meeting. Supported by NIH P30 EY010572 and an unrestricted grant from Research to Prevent Blindness. John Ng is a consultant and shareholder for Bio-Logic Aqua Research, Inc. All other authors have nothing to disclose. Address correspondence and reprint requests to John D. Ng, M.D., M.S., F.A.C.S., Casey Eye Institute, Oregon Health and Science University, 3375 SW Terwilliger Blvd, Portland, OR 97239. E-mail: ngj@ohsu.edu © 2018 by The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc., All rights reserved.

Choroidal Neovascularization Secondary to Intense Pulsed Light Injury

The authors report a 26-year-old medical device saleswoman developing choroidal neovascularization after injury by intense pulsed light with detection and monitoring by optical coherence tomography angiography and treatment with intravitreal injection of ranibizumab. This is the first intense pulsed light–related choroidal neovascularization case, which reminds the importance of using appropriate eye protection throughout the course of treatment for all individuals present in the therapy room. Accepted for publication April 4, 2018. Consent was obtained from the patient to publish clinical photos. The authors have no financial or conflicts of interest to disclose. Address correspondence and reprint requests to Shwu-Jiuan Sheu, M.D., Department of Ophthalmology, Kaohsiung Veterans General Hospital, No. 386, Dazhong 1st Road, Zuoying District, 813 Kaohsiung City, Taiwan. E-mail: sjsheu@vghks.gov.tw © 2018 by The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc., All rights reserved.

Anatomic Considerations in Thyroid Eye Disease

Purpose: To review and summarize the clinical findings in thyroid eye disease (TED) related to the unique anatomical structures of the eyelids and orbit. Methods: A PubMed search was performed searching for anatomical relationships between eyelid and orbital anatomy and the clinical findings of TED. Results: The major clinical findings associated with TED are varied. They typically involve both the eyelid and the orbit. In the eyelid, usual findings include upper eyelid retraction, contour abnormalities, eyelid edema, prolapsed orbital fat, conjunctival injection and chemosis, caruncular edema, and meibomian gland dysfunction. The exact causes of these changes remain a matter of controversy, but numerous hypotheses have been proposed, most with limited experimental support. In the orbit, inflammation and congestion characterize the acute active phase, with tissue expansion and fibrosis persisting into the chronic inactive phase. All of these findings result, at least in part, from the unique anatomy of the eyelids and orbit and their interaction with the immunologic processes underlying TED. Here we review these major characteristics of TED, with special reference to their anatomic relationships. Conclusions: The major findings characterizing TED are related to unique anatomic features in the eyelid, including Müller muscle, the levator palpebrae superioris muscle, and suspensory ligaments of the conjunctiva. In the orbit, Graves-related remolding results from the special physiologic features of the extraocular muscles, the structure of the orbital walls and their relations to adjacent paranasal sinuses, and the reaction of orbital fat to immunologic challenges. Accepted for publication March 5, 2018. The author has no financial or conflicts of interest to disclose. Diane Rothrock served as guest editor for this submission. Address correspondence and reprint requests to Jonathan J. Dutton, M.D., Ph.D., Department of Ophthalmology, University of North Carolina, Chapel Hill, NC 27707. E-mail: Jonathan_dutton@med.unc.edu © 2018 by The American Society of Ophthalmic Plastic and Reconstructive Surgery, Inc., All rights reserved.

Evaluation of the UV/H 2 O 2 system for treating natural water with a mixture of anthracene and benzo[a]pyrene at ultra-trace levels

Abstract

The presence of polycyclic aromatic hydrocarbons, such as anthracene (AN) and benzo[a]pyrene (BaP), in water has become a problem of great concern due to the detrimental health effects caused to humans and living beings. In this work, the efficiency of the UV/H₂O₂ system for degrading the target compounds at ultra-trace levels in surface water has been evaluated. For this purpose, a previous optimization step using a face-centered central composite experimental design has been conducted, considering the effect of the UV-C irradiance and the initial concentration of H₂O₂. It was evidenced that under optimal operating conditions (11 mg L⁻¹ H₂O₂ and 0.63 mW cm⁻² irradiance), AN and BaP removal percentages were higher than 99.8%. Additionally, 69.3% of the organic matter, in terms of total organic carbon, was mineralized without the production of transformation by-products more harmful than the parent compounds. These findings demonstrate the oxidation capacity of the examined system in a natural matrix for degrading micropollutants that cannot be converted through conventional treatment processes. Consequently, new horizons are opened for the effective use of the UV/H₂O₂ system for drinking water production, providing the accomplishment of other regulated parameters related to water quality.

Pesticides in indoor and outdoor residential dust: a pilot study in a rural county of Taiwan

Abstract

We conducted a pilot study to examine pesticides in dust of homes in a rural county of Taiwan. A total of 56 homes of pregnant women were included in the study. Indoor and outdoor dust was collected by a vacuum sampler and a dustpan/brush set, respectively. Nine pesticides were selected for analysis on gas chromatography-mass spectrometry with the detection limits being 0.088 ng/g or lower. The most detected pesticides were cypermethrin and chlorpyrifos, which appeared in 82.7 and 78.8% of indoor samples and 48.2 and 39.3% of outdoor samples, respectively. The detection of pesticides from indoor and outdoor dust, however, was not consistent, indicating different sources of pesticides. In addition to those two most detected, permethrin, prallethrin, and tetramethrin, which were common ingredients of insecticide products for indoor use, were also frequently found in indoor dust, suggesting that indoor use of such pesticide products may have been a major source. Fewer pesticides were found in outdoor dust, but the outdoor detection of chlorpyrifos was significantly associated with farms present inside the circles with radii of 50 and 100 m surrounding the homes (P = 0.021, 0.016). It is suggested that pesticide drift from agricultural areas to residential environments may have occurred. No seasonal effect on distribution of pesticides in dust was found, indicating that pesticides could be routinely used in Taiwan regardless of season. Compared with other international studies, this study shows relatively high levels of chlorpyrifos but low levels of pyrethroids (i.e., cypermethrin), reflecting a different pattern of pesticide use in Taiwan. Further studies need to be warranted for a better understanding of exposure to pesticides and the associated health effects.

Selecting an appropriate method to remove cyanide from the wastewater of Moteh gold mine using a mathematical approach

Abstract

The presence of cyanide ions in wastewater is dangerous to the health and life of living creatures, especially humans. Cyanide concentration should not exceed the acceptable limit in wastewaters to avoid their adverse effects to the environment. In this paper, in order to select the most appropriate method to remove cyanide from the wastewater of the Moteh gold mine, based on the experts' opinions, the use of calcium hypochlorite, sodium hypochlorite, and hydrogen peroxide was chosen as forerunning alternative in the form of a multi-stage model. Then, seven criteria including the amount of material consumed, ease of implementation, safety, ability to remove cyanide, pH, time, and cost of the process to assess the considered methods were determined. Afterwards, seven experts conducted numerous experiments to examine the conditions of each of these criteria. Then, by employing a mathematical method called "numerical taxonomy," the use of sodium hypochlorite was suggested as the best method to remove cyanide from the wastewater of the Moteh gold mine. Finally, the TOPSIS model was used to validate the proposed model, which led to the same results of the suggested method. Also, the results of employing taxonomic analysis and TOPSIS method suggested the use of sodium hypochlorite as the best method for cyanide removal from wastewater. In addition, according to the analysis of various experiments, conditions for complete removal of cyanide using sodium hypochlorite included concentration (8.64 g/L), pH (12.3), and temperature (12 °C).

Consistently Very Poorly Controlled Asthma is Associated with Greater Activity and School Impairment in Children with Severe or Difficult-to-Treat Asthma

Publication date: Available online 5 June 2018
Source:The Journal of Allergy and Clinical Immunology: In Practice
Author(s): Leonard B. Bacharier, Ronina A. Covar, Tmirah Haselkorn, Ahmar Iqbal, Cynthia Alvarez, David R. Mink, Hubert Chen, Robert S. Zeiger

A Retrospective Critical Analysis and Risk Stratification of Penicillin Allergy De-labelling in a UK Specialist Regional Allergy Service

Publication date: Available online 5 June 2018
Source:The Journal of Allergy and Clinical Immunology: In Practice
Author(s): Omar E. Mohamed, Sarah Beck, Aarnoud Huissoon, Cathryn Melchior, Jane Heslegrave, Richard Baretto, Anjali Ekbote, Mamidipudi Thirumala Krishna
BackgroundA spurious label of penicillin allergy (Pen-A) negatively impacts on antibiotic stewardship and healthcare costs. Recent studies have proposed a guideline-steered direct penicillin challenge without undertaking allergy tests when 'true allergy' is unlikely.ObjectiveCritically analyse Pen-A clinical presentation, perform risk stratification and determine clinical predictors for 'true allergy'.MethodRetrospective data extraction from clinical and electronic patient records.Results231 patients (M= 82; F=149; mean age 51.22 (SD ± 18.07 years) were analysed. Based on clinical history, patients were categorised as likely type I hypersensitivity [HSR] (n=27), likely type IV HSR (n=65), indeterminate (n=111) and HSR unlikely (n=28). Based on index reaction and co-morbidities, patients were classified into 'low risk' (n=143) and 'high risk' (n=78). Pen-A was excluded in 74% of patients assessed having likely type I HSR, 91% with likely type IV HSR, 93% of indeterminate and 100% of HSR unlikely patients. Negative predictive value for successful de-labelling in the 'low risk' group was 94% (odds ratio [OR] - 2.9; p= 0.02). Predictors for 'true Pen-A' were history of anaphylaxis (OR - 30.6; p < 0.001), hospitalization (OR - 7; p<0.001), ≤5 years since index reaction (OR - 3; p= 0.04).ConclusionSystematic clinical characterisation and risk stratification has an important role in Pen-A de-labelling. These data provide proof of concept for a guideline-based selection of patients labelled with Pen-A for a direct penicillin challenge. Patients in the 'low risk' group seem suitable for this intervention, although a rigorous prospective evaluation is needed in a multi-centre study.

Ara h 2 is detectable on surfaces of commercial airplanes

Publication date: Available online 5 June 2018
Source:The Journal of Allergy and Clinical Immunology: In Practice
Author(s): Jay J. Jin, Joshua M. Dorn, John Yunginger, Nancy L. Ott
Peanuts are frequently served on commercial airplanes and have been the source of numerous self-reported allergic reactions. Small amounts of Ara h 2 were consistently detected on surfaces of commercial airplanes but not in air samples. Avoidance recommendations, such as wiping surfaces, will reduce inadvertent contact exposure to peanut in peanut allergic travelers.

Contribution of particulate matter in storm runoff to organic phosphorus loads in urban rivers

Abstract

To help us control pollution caused by urban runoff, we need to understand how particulate matter in storm runoff contributes to the total pollutant load. In this study, we collected samples from ten sites along on the banks of an urban river during five rainfall events. We determined the grain size and phosphorus (P) forms in the particulate matter to assess how much P there was in storm runoff. The results showed that the particles were mostly medium-sized, and particles with a diameter of less than 850 μm but greater than 150 μm accounted for 50% of the total particulate matter. The average particulate P concentration, at 298.7 mg/kg, was high and was mostly organic P (Po), which had an average concentration of 134.64 mg/kg. The concentrations of the different P forms varied with particle size. The main fraction in the large-sized grains was acid-extractable inorganic P (Pi), while Po and alkalinity-extractable Pi dominated in medium- and small-sized particles. Overall, our results illustrate that, by enhancing the control of particulate matter in storm runoff, P, and in particular Po, inputs to urban rivers can be reduced.

Characterization of Staphylococcus aureus strains and evidence for the involvement of non-classical enterotoxin genes in food poisoning outbreaks

Abstract

To an increasing extent, molecular and genetic characterization is now used to investigate foodborne outbreaks. The aim of this study was to seek molecular links among coagulase-positive staphylococci (CPS) isolated from three recent food poisoning outbreaks in Romania using polymerase chain reaction and pulsed-field gel electrophoresis (PFGE) techniques. Nineteen CPS isolates were identified as Staphylococcus aureus by detection of the 23S rDNA gene. Among them, 15 carried at least one staphylococcal enterotoxin-encoding gene (se). The Calarași outbreak strains grouped in pulsotype 2 and were sed/sej/ser-positive, whereas the Arad outbreak strains clustered in pulsotype 17 and were either sed/seg/sei/sej/ser- or seg/sei-positive. The Pitești outbreak strains clustered in pulsotype 1 and, surprisingly, possessed only one enterotoxin gene, i.e. seh. Similar to other European countries, the seh gene has been identified with increasing frequency in Romanian outbreaks; this highlights the importance of considering the application of methods recommended for staphylococcal enterotoxin regulation in Europe.

Si quieres ir rápido ve solo, si quieres llegar lejos ve acompañado

Publication date: June 2018
Source:Actas Dermo-Sifiliográficas, Volume 109, Issue 5
Author(s): Yolanda Gilaberte

Objetivo DIADERM: el diagnóstico en la consulta externa de dermatología

Publication date: June 2018
Source:Actas Dermo-Sifiliográficas, Volume 109, Issue 5
Author(s): R.M. Díaz Díaz

Conversion of Eragrostis plana Nees leaves to activated carbon by microwave-assisted pyrolysis for the removal of organic emerging contaminants from aqueous solutions

Abstract

Eragrostis plana Nees leaves, abundant lignocellulosic biomass, was used as carbon source for preparation of activated carbon, by using microwave-assisted pyrolysis and chemical activation. The novel activated carbon (MWEPN) was characterised by FTIR, CHN elemental analysis, Boehm's titration method, TGA, SEM, N₂ adsorption/desorption curves and pH of the point of zero charge (pH_pzc). Afterwards, the adsorbent was successfully employed for adsorption of the two emerging contaminants (caffeine and 2-nitrophenol). The results indicated that MWEPN had a predominantly mesoporous structure with a high surface area of 1250 m² g⁻¹. FTIR analysis indicated the presence of carbonyl, hydroxyl and carboxylic groups on the surface of MWEPN. The Boehm analysis showed the existence of the high amount of acid moieties on the surface of activated carbon. Adsorption kinetic indicated that the system followed the Avrami fractional order at the optimal pH of 7. The equilibrium time was attained at 30 min. The Liu isotherm model better described the isothermal data. Based on the Liu isotherm, the maximum sorption capacities (Q_max) of caffeine and 2-nitrophenol adsorbed onto activated carbon at 25 °C were 235.5 and 255.8 mg g⁻¹, respectively.

Evaluation of Fe-containing Li 2 CuO 2 on CO 2 capture performed at different physicochemical conditions

Abstract

Li₂CuO₂ and different iron-containing Li₂CuO₂ samples were synthesized by solid state reaction. On iron-containing samples, atomic sites of copper are substituted by iron ions in the lattice (XRD and Rietveld analyses). Iron addition induces copper release from Li₂CuO₂, which produce cationic vacancies and CuO, due to copper (Cu²⁺) and iron (Fe³⁺) valence differences. Two different physicochemical conditions were used for analyzing CO₂ capture on these samples; (i) high temperature and (ii) low temperature in presence of water vapor. At high temperatures, iron addition increased CO₂ chemisorption, due to structural and chemical variations on Li₂CuO₂. Kinetic analysis performed by first order reaction and Eyring models evidenced that iron addition on Li₂CuO₂ induced a faster CO₂ chemisorption but a higher thermal dependence. Conversely, CO₂ chemisorption at low temperature in water vapor presence practically did not vary by iron addition, although hydration and hydroxylation processes were enhanced. Moreover, under these physicochemical conditions the whole sorption process became slower on iron-containing samples, due to metal oxides presence.

Water shortage risk assessment considering large-scale regional transfers: a copula-based uncertainty case study in Lunan, China

Abstract

The risk of water shortage caused by uncertainties, such as frequent drought, varied precipitation, multiple water resources, and different water demands, brings new challenges to the water transfer projects. Uncertainties exist for transferring water and local surface water; therefore, the relationship between them should be thoroughly studied to prevent water shortage. For more effective water management, an uncertainty-based water shortage risk assessment model (UWSRAM) is developed to study the combined effect of multiple water resources and analyze the shortage degree under uncertainty. The UWSRAM combines copula-based Monte Carlo stochastic simulation and the chance-constrained programming-stochastic multiobjective optimization model, using the Lunan water-receiving area in China as an example. Statistical copula functions are employed to estimate the joint probability of available transferring water and local surface water and sampling from the multivariate probability distribution, which are used as inputs for the optimization model. The approach reveals the distribution of water shortage and is able to emphasize the importance of improving and updating transferring water and local surface water management, and examine their combined influence on water shortage risk assessment. The possible available water and shortages can be calculated applying the UWSRAM, also with the corresponding allocation measures under different water availability levels and violating probabilities. The UWSRAM is valuable for mastering the overall multi-water resource and water shortage degree, adapting to the uncertainty surrounding water resources, establishing effective water resource planning policies for managers and achieving sustainable development.

Probe versus microscope: a comparison of different methods for image-to-patient registration

Abstract

Purpose

Computer-aided navigation is widely used in ENT surgery. The position of a surgical instrument is shown in the CT/MR images of the patient and can thus be a good support for the surgeon. The accuracy is highly dependent on the registration done prior to surgery. A microscope and a probe can both be used for registration and navigation, depending on the surgical intervention. A navigation system typically only reports the fiducial registration error after paired-point registration. However, the target registration error (TRE)—a measurement for the accuracy in the surgical area—is much more relevant. The aim of this work was to compare the performance of a microscope relative to a conventional probe-based approach with different registration methods.

Methods

In this study, optical tracking was used to register a plastic skull to its preoperative CT images with paired-point registration. Anatomical landmarks and skin-affixed markers were used as fiducials and targets. With both microscope and probe, four different registration methods were evaluated based on their TREs at 10 targets. For half of the experiments, a surface registration and/or external fiducials were used additionally to paired-point registration to study their influence to accuracy.

Results

Overall, probe registration leads to a smaller TRE ( \(1.69 \pm 0.74\,\hbox {mm}\) ) than registration with a microscope ( \(2.19 \pm 0.94\,\hbox {mm}\) ). Additional surface registration does not result in better accuracy of navigation for microscope and probe. The lowest mean TRE for both pointers can be achieved with paired-point registration only and radiolucent markers.

Conclusion

Our experiments showed that a probe used for registration and navigation achieves lower TREs compared using a microscope. Neither additional surface registration nor additional fiducials on an external reference element are necessary for improved accuracy of navigated ENT surgery on a plastic skull.

Ultrasound-based liver tracking utilizing a hybrid template/optical flow approach

Abstract

Purpose

With the ongoing shift toward reduced invasiveness in many surgical procedures, methods for tracking moving targets within the body become vital. Non-invasive treatment methods such as stereotactic radiation therapy and high intensity focused ultrasound, in particular, rely on the accurate localization of targets throughout treatment to ensure optimal treatment provision. This work aims at developing a robust, accurate and fast method for target tracking based on ultrasound images.

Methods

A method for tracking of targets in real-time ultrasound image data was developed, based on the combination of template matching, dense optical flow and image intensity information. A weighting map is generated from each of these approaches which are then normalized, weighted and combined, with the weighted mean position then calculated to predict the current position. The approach was evaluated on the Challenge for Liver Ultrasound Tracking 2015 dataset, consisting of a total of 24 training and 39 test datasets with a total of 53 and 85 annotated targets throughout the liver, respectively.

Results

The proposed method was implemented in MATLAB and achieved an accuracy of \(0.80\pm 0.80\) (95%: 1.91) mm and \(0.74\pm 1.03\) (95%: 1.85) mm on the training and test data, respectively. Tracking frequencies of between 8 and 36 fps (mean of 22 fps) were observed, largely dependent on the size of the region of interest. The achieved results represent an improvement in mean accuracy of approximately 0.3 mm over the reported methods in existing literature.

Conclusions

This work describes an accurate and robust method for the tracking of points of interest within 2D ultrasound data, based on a combination of multi-template matching, dense optical flow and relative image intensity information.