This study evaluated the effect of various head orientations during cone-beam computed tomography (CBCT) image acquisition on linear measurements of potential implant sites.
Six dry human skulls with ...a total of 28 implant sites were evaluated for seven different head orientations. The scans were acquired using a Hitachi CB-MercuRay CBCT machine. The scanned volumes were reconstructed. Horizontal and vertical measurements were made and were compared to measurements made after simulating the head position to corrected head angulations. Data was analyzed using a two-way ANOVA test.
Statistical analysis revealed a significant interaction between the mean errors in vertical measurements with a marked difference observed at the extension head position (P<0.05). Statistical analysis failed to yield any significant interaction between the mean errors in horizontal measurements at various head positions.
Head orientation could significantly affect the vertical measurements in CBCT scans. The main head position influencing the measurements is extension.
Purpose:
To determine the variability of Cone‐Beam CT Dose Index (CB‐CTDI) across multiple on‐board imaging (OBI) systems within a single institution, and compare this to manufacturer provided data.
...Methods:
The CB‐CTDI was measured on three Trilogy and three TrueBeam Varian OBI systems, for six different clinically used scan protocols. Measurements were taken using a 10 cm long CT ionization chamber in either a 16 cm (head‐simulating) or 32 cm (body‐simulating) diameter, acrylic, cylindrical, 15 cm long CTDI phantom. We assessed the variation in CB‐CTDI between the OBI systems and compared our measured values to the data provided by the manufacturer.
Results:
The standard error in the CB‐CTDI measured for all protocols was found to be within ±2% and ±5% of the mean for TrueBeam and Trilogy, respectively. For all head scan protocols, the measured TrueBeam values were lower than the manufacturer's reported values, with a maximum difference of 13.9% and an average difference of 11%. For the body scan protocols, the TrueBeam measured values were 3% and 13% greater than the manufacturer's reported values for two out of three protocols, and 38% lower than reported for the third protocol. In total, 7/18 CB‐CTDI measurements fell within the manufacturers specified range (±10%). Across all scans the Truebeam machines were found to have a lower CB‐CTDI than Trilogy, particularly the head scan protocols, which show decreases of up to 30% .
Conclusion:
The intra‐institutional variation of CB‐CTDI was found to be clinically acceptable at less than 5%. For the TrueBeam OBI system, over half of the measured scans failed to fall with in the manufactured quoted range of 10%, however, all measured values were within 15% of the manufacturer's reported values. For accurate assessment and reporting of imaging dose to radiotherapy patients, our results indicate a need for standardization in CB‐CTDI measurement technique.
Hypersensitivity pneumonitis is an unusual complication of using humidification devices. It is characterized by the acute onset of dyspnea, cough, fever, and chills after exposure to an offending ...antigen. This report describes a 54-year-old female laryngectomee who had repeated hospitalizations for postoperative dyspnea with normal chest roentgenograms and sputum cultures, but findings and history consistent with acute hypersensitivity pneumonitis. This seems to be the first reported case of hypersensitivity pneumonitis in a laryngectomee using a home mist machine. When repeated episodes of dyspnea occur in such patients, hypersensitivity pneumonitis should be considered in the differential diagnosis.
Purpose: This study evaluated the effect of various head orientations during cone-beam computed tomography (CBCT) image acquisition on linear measurements of potential implant sites. Materials and ...Methods: Six dry human skulls with a total of 28 implant sites were evaluated for seven different head orientations. The scans were acquired using a Hitachi CB-MercuRay CBCT machine. The scanned volumes were reconstructed. Horizontal and vertical measurements were made and were compared to measurements made after simulating the head position to corrected head angulations. Data was analyzed using a two-way ANOVA test. Results: Statistical analysis revealed a significant interaction between the mean errors in vertical measurements with a marked difference observed at the extension head position (P<0.05). Statistical analysis failed to yield any significant interaction between the mean errors in horizontal measurements at various head positions. Conclusion: Head orientation could significantly affect the vertical measurements in CBCT scans. The main head position influencing the measurements is extension.
GEOTECHNICAL DRILLING/EXPLORATION DRILLING The Geoprobe® 3230DT is a midsized tracked drill rig combining advanced direct push functionality with traditional geotechnical auger rig and high-speed ...rotary drilling capabilities. Using customer feedback and experience, we combined all of the features that make drilling easy into this machine, creating a platform that performs well in direct push and rotary applications. The patented CB Combo Head is capable of putting high-torque power into hollow stem augers while also having the control and finesse to run high-speed wet rotary and wireline tools.
The report examines the market for microphones, speakers, and end-applications Key Topics Covered: Chapter 1 Introduction 1.1 Technology of Silicon Microphones 1.2 Advantages of Silicon Microphones ...Chapter 2 Microphone Market Chapter 3 Micro Speaker Markets 3.1 Introduction 3.2 Cellular Handset Audio Speakers 3.3 Consumer Audio Speakers Chapter 4 Microphone and Speaker Supplier Profiles Chapter 5 Headset Markets 5.1 The Contact Center/Office Market 5.2 Mobile Market/PC Headset Market 5.3 Bluetooth Headset Market 5.4 Aviation Headset Market 5.5 Headphones Chapter 6 End Application Markets 6.1 Answering Machines 6.2 Audio Conferencing 6.3 Automotive Telematics 6.4 Cellular Phones 6.5 CB Radios 6.6 Corded Phones 6.7 Cordless Phones 6.8 Digital Cameras 6.9 Fax Machines 6.11 Hearing Aids 6.12 Integrated Laser/Radar Detector 6.13 Medical devices 6.14 Mobile computing 6.15 Networked homes 6.16 Paging 6.17 PCs 6.18 PDAs 6.19 Smartphones 6.20 Video Cameras 6.21 Video Conference systems 6.22 Walkie Talkie's / Two Way Radio's For more information visit http://www.researchandmarkets.com/research/33c8pp/silicon Media Contact: Laura Wood, +353-1-481-1716, press@researchandmarkets.net To view the original version on PR Newswire, visit:http://www.prnewswire.com/news-releases/global-silicon-microphones-and-speakers-technology-market-and-end-applications-analysis-2015-300136795.html SOURCE Research and Markets Credit: Research and Markets
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