Dosimetric comparison between coplanar and non coplanar field radiotherapy for ethmoid sinus cancer

<p>Abstract</p> <p>Background</p> <p>To compare non coplanar field (NCF) with coplanar field (CF) -intensity-modulated radiotherapy (IMRT) planning for ethmoid cancer.</p> <p>Methods</p> <p>Seven patients treated with NCF IMRT for ethmoid cancer were studied. A CF IMRT optimization was prepared with the same constraints as for the NCF treatment. The maximum point doses (D max) obtained for the different optic pathway structures (OPS) should differ no more than 3% from those achieved with the NCF IMRT plan. The distribution of the dose in the target volume and in the critical structures was compared between the two techniques, as well as the Conformity (CI) and the Homogeneity Indexes (HI) in the target volume.</p> <p>Results</p> <p>We noted no difference between the two techniques in the OPS for the D1, D2, and D5%, in the inner ear and controlateral lens for the average Dmax, in the temporo-mandibular joints for the average mean dose, in the cord and brainstem for the average D1%. The dose-volume histograms were slightly better with the NCF treatment plan for the planning target volume (PTV) with a marginally better HI but no impact on CI. We found a great improvement in the PTV coverage with the CF treatment plan for two patients with T4 tumors.</p> <p>Conclusion</p> <p>IMRT is one of the treatment options for ethmoid cancer. The PTV coverage is optimal without compromising the protection of the OPS. The impact of non coplanar versus coplanar set up is very slight.</p

Ten golden rules for optimal antibiotic use in hospital settings: the WARNING call to action

Antibiotics are recognized widely for their benefits when used appropriately. However, they are often used inappropriately despite the importance of responsible use within good clinical practice. Effective antibiotic treatment is an essential component of universal healthcare, and it is a global responsibility to ensure appropriate use. Currently, pharmaceutical companies have little incentive to develop new antibiotics due to scientific, regulatory, and financial barriers, further emphasizing the importance of appropriate antibiotic use. To address this issue, the Global Alliance for Infections in Surgery established an international multidisciplinary task force of 295 experts from 115 countries with different backgrounds. The task force developed a position statement called WARNING (Worldwide Antimicrobial Resistance National/International Network Group) aimed at raising awareness of antimicrobial resistance and improving antibiotic prescribing practices worldwide. The statement outlined is 10 axioms, or “golden rules,” for the appropriate use of antibiotics that all healthcare workers should consistently adhere in clinical practice

GIS-Based mapping of Areas Sensitive to Desertification in a Semi-Arid Region in Lebanon

Desertification is a land degradation problem of major importance in the arid and semi-arid regions of the world. Land degradation and global climate change are closely related. Although climate-change mitigation requires global solutions, individuals and communities can successfully reduce land degradation at the local level. Plans has emerged to combat desertification, which included constructing solar power plants, establishing alternative crops in the sand, wastewater management, afforestation, etc. While in Lebanon areas prone to desertification are already investigated by UNCCD (United Nations Convention to Combat Desertification), Bekaa area shows the most critical land degradation situation. This study aims to identify and map the vulnerability to desertification in a semi-arid area in Lebanon, namely Baalbeck and Hermel, using modified MEDALUS (Mediterranean Desertification and Land Use) approach. Thematic layers of soils, vegetation, climate and management quality indices are the main inputs for estimating the Environmentally Sensitive Area (ESA). These layers were extracted and manipulated from soil map (1/50000), geological map (1/20000), DEM (10m), MOD16 - MODIS monthly Evapotranspiration datasets (1 km), Land Cover/Use map (1/20000) of the region in 2005, and calibrated climatic satellite imageries (TRMM data). The study area was classified into 8 classes same as in the standard MEDALUS. Results show that 92% of the study region is characterized by a critical sensitivity to desertification, whereas, less than 0.1 km2 are a non-affected areas. The proposed methodology has proven to be easy to apply and shall be portable to other semi-arid regions in the Mediterranean area. The outputs shall be used in several MEDALUS advanced hydrological models (e.g. MERDUSH, SHETRAN)

Assessment of the level of maxillary sinus floor in dentulous, edentulous and free end cases on a sample of Malay population using orthopantomogram

Introduction: Knowledge about the relation between the floor of the maxillary sinus and the teeth\area considered an important and essential for dental practitioners for the planning of many surgical procedures in this area. Objective: The purpose of this study was to assess the level of maxillary sinus floor in dentulous, edentulous and free end cases among Malay population based on gender, and age by using panoramic radiographs. Methods: Sample size was 364 cases including 118 dentulous, 192 edentulous, and 54 free ends. Measuring the distance between maxillary sinus floor and either root apices of upper posterior teeth or residual ridge in dentulous cases, edentulous and free end cases, and study the relation of this distance with gender and age. Results: The distance in dentulous have no relation to the age and gender and vice versa in edentulous and free end cases. Conclusion: The distance not affected by age and gender in dentulous cases, while it is effective in edentulous and free end case

Maximum doses in optic pathways, respectively optic chiasma (a), ipsilateral optic nerve (b) and controlateral optic nerve (c)

<p><b>Copyright information:</b></p><p>Taken from "Dosimetric comparison between coplanar and non coplanar field radiotherapy for ethmoid sinus cancer"</p><p>http://www.ro-journal.com/content/2/1/35</p><p>Radiation Oncology (London, England) 2007;2():35-35.</p><p>Published online 18 Sep 2007</p><p>PMCID:PMC2072954.</p><p></p> For each patient (Px), the maximum dose for coplanar field CF (grey) and for non coplanar field NCF (black) is represented

Mean dose volume histogram in the planning target volume for the coplanar field CF (grey) and non coplanar field technique NCF (black)

<p><b>Copyright information:</b></p><p>Taken from "Dosimetric comparison between coplanar and non coplanar field radiotherapy for ethmoid sinus cancer"</p><p>http://www.ro-journal.com/content/2/1/35</p><p>Radiation Oncology (London, England) 2007;2():35-35.</p><p>Published online 18 Sep 2007</p><p>PMCID:PMC2072954.</p><p></p> Minimum and maximum doses of the study group are represented by dotted lines

Homogeneity index (HI) for each patient in the coplanar field CF (grey) and non coplanar field NCF (black) technique

<p><b>Copyright information:</b></p><p>Taken from "Dosimetric comparison between coplanar and non coplanar field radiotherapy for ethmoid sinus cancer"</p><p>http://www.ro-journal.com/content/2/1/35</p><p>Radiation Oncology (London, England) 2007;2():35-35.</p><p>Published online 18 Sep 2007</p><p>PMCID:PMC2072954.</p><p></p> HI is defined as the difference between D1 and D99% divided by the prescribed dose. A perfect homogeneity would be reached with a zero index