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Sample records for lung volume calculated

  1. Comparison of distinctive models for calculating an interlobar emphysema heterogeneity index in patients prior to endoscopic lung volume reduction.

    Science.gov (United States)

    Theilig, Dorothea; Doellinger, Felix; Poellinger, Alexander; Schreiter, Vera; Neumann, Konrad; Hubner, Ralf-Harto

    2017-01-01

    The degree of interlobar emphysema heterogeneity is thought to play an important role in the outcome of endoscopic lung volume reduction (ELVR) therapy of patients with advanced COPD. There are multiple ways one could possibly define interlobar emphysema heterogeneity, and there is no standardized definition. The aim of this study was to derive a formula for calculating an interlobar emphysema heterogeneity index (HI) when evaluating a patient for ELVR. Furthermore, an attempt was made to identify a threshold for relevant interlobar emphysema heterogeneity with regard to ELVR. We retrospectively analyzed 50 patients who had undergone technically successful ELVR with placement of one-way valves at our institution and had received lung function tests and computed tomography scans before and after treatment. Predictive accuracy of the different methods for HI calculation was assessed with receiver-operating characteristic curve analysis, assuming a minimum difference in forced expiratory volume in 1 second of 100 mL to indicate a clinically important change. The HI defined as emphysema score of the targeted lobe (TL) minus emphysema score of the ipsilateral nontargeted lobe disregarding the middle lobe yielded the best predicative accuracy (AUC =0.73, P =0.008). The HI defined as emphysema score of the TL minus emphysema score of the lung without the TL showed a similarly good predictive accuracy (AUC =0.72, P =0.009). Subgroup analysis suggests that the impact of interlobar emphysema heterogeneity is of greater importance in patients with upper lobe predominant emphysema than in patients with lower lobe predominant emphysema. This study reveals the most appropriate ways of calculating an interlobar emphysema heterogeneity with regard to ELVR.

  2. Comparison of distinctive models for calculating an interlobar emphysema heterogeneity index in patients prior to endoscopic lung volume reduction

    Directory of Open Access Journals (Sweden)

    Theilig D

    2017-06-01

    Full Text Available Dorothea Theilig,1 Felix Doellinger,1 Alexander Poellinger,1 Vera Schreiter,1 Konrad Neumann,2 Ralf-Harto Hubner31Department of Radiology, Charité Campus Virchow Klinikum, Charité, Universitätsmedizin Berlin, Berlin, Germany; 2Institute of Biometrics and Clinical Epidemiology, Charité Campus Benjamin Franklin, Charité, Universitätsmedizin Berlin, Berlin, Germany; 3Department of Pneumology, Charité Campus Virchow Klinikum, Charité, Universitätsmedizin Berlin, Berlin, GermanyBackground: The degree of interlobar emphysema heterogeneity is thought to play an important role in the outcome of endoscopic lung volume reduction (ELVR therapy of patients with advanced COPD. There are multiple ways one could possibly define interlobar emphysema heterogeneity, and there is no standardized definition.Purpose: The aim of this study was to derive a formula for calculating an interlobar emphysema heterogeneity index (HI when evaluating a patient for ELVR. Furthermore, an attempt was made to identify a threshold for relevant interlobar emphysema heterogeneity with regard to ELVR.Patients and methods: We retrospectively analyzed 50 patients who had undergone technically successful ELVR with placement of one-way valves at our institution and had received lung function tests and computed tomography scans before and after treatment. Predictive accuracy of the different methods for HI calculation was assessed with receiver-operating characteristic curve analysis, assuming a minimum difference in forced expiratory volume in 1 second of 100 mL to indicate a clinically important change.Results: The HI defined as emphysema score of the targeted lobe (TL minus emphysema score of the ipsilateral nontargeted lobe disregarding the middle lobe yielded the best predicative accuracy (AUC =0.73, P=0.008. The HI defined as emphysema score of the TL minus emphysema score of the lung without the TL showed a similarly good predictive accuracy (AUC =0.72, P=0.009. Subgroup

  3. Lung volumes: measurement, clinical use, and coding.

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    Flesch, Judd D; Dine, C Jessica

    2012-08-01

    Measurement of lung volumes is an integral part of complete pulmonary function testing. Some lung volumes can be measured during spirometry; however, measurement of the residual volume (RV), functional residual capacity (FRC), and total lung capacity (TLC) requires special techniques. FRC is typically measured by one of three methods. Body plethysmography uses Boyle's Law to determine lung volumes, whereas inert gas dilution and nitrogen washout use dilution properties of gases. After determination of FRC, expiratory reserve volume and inspiratory vital capacity are measured, which allows the calculation of the RV and TLC. Lung volumes are commonly used for the diagnosis of restriction. In obstructive lung disease, they are used to assess for hyperinflation. Changes in lung volumes can also be seen in a number of other clinical conditions. Reimbursement for measurement of lung volumes requires knowledge of current procedural terminology (CPT) codes, relevant indications, and an appropriate level of physician supervision. Because of recent efforts to eliminate payment inefficiencies, the 10 previous CPT codes for lung volumes, airway resistance, and diffusing capacity have been bundled into four new CPT codes.

  4. Validation study of an interpolation method for calculating whole lung volumes and masses from reduced numbers of CT-images in ponies.

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    Reich, H; Moens, Y; Braun, C; Kneissl, S; Noreikat, K; Reske, A

    2014-12-01

    Quantitative computer tomographic analysis (qCTA) is an accurate but time intensive method used to quantify volume, mass and aeration of the lungs. The aim of this study was to validate a time efficient interpolation technique for application of qCTA in ponies. Forty-one thoracic computer tomographic (CT) scans obtained from eight anaesthetised ponies positioned in dorsal recumbency were included. Total lung volume and mass and their distribution into four compartments (non-aerated, poorly aerated, normally aerated and hyperaerated; defined based on the attenuation in Hounsfield Units) were determined for the entire lung from all 5 mm thick CT-images, 59 (55-66) per animal. An interpolation technique validated for use in humans was then applied to calculate qCTA results for lung volumes and masses from only 10, 12, and 14 selected CT-images per scan. The time required for both procedures was recorded. Results were compared statistically using the Bland-Altman approach. The bias ± 2 SD for total lung volume calculated from interpolation of 10, 12, and 14 CT-images was -1.2 ± 5.8%, 0.1 ± 3.5%, and 0.0 ± 2.5%, respectively. The corresponding results for total lung mass were -1.1 ± 5.9%, 0.0 ± 3.5%, and 0.0 ± 3.0%. The average time for analysis of one thoracic CT-scan using the interpolation method was 1.5-2 h compared to 8 h for analysis of all images of one complete thoracic CT-scan. The calculation of pulmonary qCTA data by interpolation from 12 CT-images was applicable for equine lung CT-scans and reduced the time required for analysis by 75%. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Comparative evaluation of hemodynamic and respiratory parameters during mechanical ventilation with two tidal volumes calculated by demi-span based height and measured height in normal lungs

    Directory of Open Access Journals (Sweden)

    L Mousavi Seresht

    2014-01-01

    Full Text Available Background : Appropriate determination of tidal volume (VT is important for preventing ventilation induced lung injury. We compared hemodynamic and respiratory parameters in two conditions of receiving VTs calculated by using body weight (BW, which was estimated by measured height (HBW or demi-span based body weight (DBW. Materials and Methods : This controlled-trial was conducted in St. Alzahra Hospital in 2009 on American Society of Anesthesiologists (ASA I and II, 18-65-years-old patients. Standing height and weight were measured and then height was calculated using demi-span method. BW and VT were calculated with acute respiratory distress syndrome-net formula. Patients were randomized and then crossed to receive ventilation with both calculated VTs for 20 min. Hemodynamic and respiratory parameters were analyzed with SPSS version 20.0 using univariate and multivariate analyses. Results : Forty nine patients were studied. Demi-span based body weight and thus VT (DTV were lower than Height based body weight and VT (HTV (P = 0.028, in male patients (P = 0.005. Difference was observed in peak airway pressure (PAP and airway resistance (AR changes with higher PAP and AR at 20 min after receiving HTV compared with DTV. Conclusions : Estimated VT based on measured height is higher than that based on demi-span and this difference exists only in females, and this higher VT results higher airway pressures during mechanical ventilation.

  6. Calculation of the capnographic index based on expiratory molar mass-volume-curves--a suitable tool to screen for cystic fibrosis lung disease.

    Science.gov (United States)

    Fuchs, Susanne I; Junge, Sibylle; Ellemunter, Helmut; Ballmann, Manfred; Gappa, Monika

    2013-05-01

    Volumetric capnography reflecting the course of CO2-exhalation is used to assess ventilation inhomogeneity. Calculation of the slope of expiratory phase 3 and the capnographic index (KPIv) from expirograms allows quantification of extent and severity of small airway impairment. However, technical limitations have hampered more widespread use of this technique. Using expiratory molar mass-volume-curves sampled with a handheld ultrasonic flow sensor during tidal breathing is a novel approach to extract similar information from expirograms in a simpler manner possibly qualifying as a screening tool for clinical routine. The aim of the present study was to evaluate calculation of the KPIv based on molar mass-volume-curves sampled with an ultrasonic flow sensor in patients with CF and controls by assessing feasibility, reproducibility and comparability with the Lung Clearance Index (LCI) derived from multiple breath washout (MBW) used as the reference method. Measurements were performed in patients with CF and healthy controls during a single test occasion using the EasyOne Pro, MBW Module (ndd Medical Technologies, Switzerland). Capnography and MBW were performed in 87/96 patients with CF and 38/42 controls, with a success rate of 90.6% for capnography. Mean age (range) was 12.1 (4-25) years. Mean (SD) KPIv was 6.94 (3.08) in CF and 5.10 (2.06) in controls (p=0.001). Mean LCI (SD) was 8.0 (1.4) in CF and 6.2 (0.4) in controls (p=molar mass-volume-curves is feasible. KPIv is significantly different between patients with CF and controls and correlates with the LCI. However, individual data revealed a relevant overlap between patients and controls requiring further evaluation, before this method can be recommended for clinical use. Copyright © 2012 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

  7. Planimetric determination of lung volume

    International Nuclear Information System (INIS)

    Bieber, M.; Maurer, H.J.

    1984-01-01

    The total volume of the lungs was determined by digital planimetry in 102 patients with emphysema and 33 normal controls aged between 30 and 79 years. The results were compared with the findings obtained from spirometric measurements. Mean values showed a significant relationship to age, body size and body surface. Planimetrically determined lung volume did not show a linear relationship with age, but increased after 60 years. Beyong 60 years, spirometric findings were lower because of an increase in the number of patients with emphysema. The results have shown that digital planimetry is a useful addition to spirometry. (orig.) [de

  8. Lung volume reduction for emphysema.

    Science.gov (United States)

    Shah, Pallav L; Herth, Felix J; van Geffen, Wouter H; Deslee, Gaetan; Slebos, Dirk-Jan

    2017-02-01

    Advanced emphysema is a lung disease in which alveolar capillary units are destroyed and supporting tissue is lost. The combined effect of reduced gas exchange and changes in airway dynamics impairs expiratory airflow and leads to progressive air trapping. Pharmacological therapies have limited effects. Surgical resection of the most destroyed sections of the lung can improve pulmonary function and exercise capacity but its benefit is tempered by significant morbidity. This issue stimulated a search for novel approaches to lung volume reduction. Alternative minimally invasive approaches using bronchoscopic techniques including valves, coils, vapour thermal ablation, and sclerosant agents have been at the forefront of these developments. Insertion of endobronchial valves in selected patients could have benefits that are comparable with lung volume reduction surgery. Endobronchial coils might have a role in the treatment of patients with emphysema with severe hyperinflation and less parenchymal destruction. Use of vapour thermal energy or a sclerosant might allow focal treatment but the unpredictability of the inflammatory response limits their current use. In this Review, we aim to summarise clinical trial evidence on lung volume reduction and provide guidance on patient selection for available therapies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Measurement of lung volume by lung perfusion scanning using SPECT and prediction of postoperative respiratory function

    International Nuclear Information System (INIS)

    Andou, Akio; Shimizu, Nobuyosi; Maruyama, Shuichiro

    1992-01-01

    Measurement of lung volume by lung perfusion scanning using single photon emission computed tomography (SPECT) and its usefulness for the prediction of respiratory function after lung resection were investigated. The lung volumes calculated in 5 patients by SPECT (threshold level 20%) using 99m Tc-macroaggregated albumin (MAA), related very closely to the actually measured lung volumes. This results prompted us to calculate the total lung volume and the volume of the lobe to be resected in 18 patients with lung cancer by SPECT. Based on the data obtained, postoperative respiratory function was predicted. The predicted values of forced vital capacity (FVC), forced expiratory volume (FEV 1.0 ), and maximum vital volume (MVV) showed closer correlations with the actually measured postoperative values (FVC, FEV 1.0 , MVV : r=0.944, r=0.917, r=0.795 respectively), than the values predicted by the ordinary lung perfusion scanning. This method facilitates more detailed evaluation of local lung function on a lobe-by-lobe basis, and can be applied clinically to predict postoperative respiratory function. (author)

  10. Pseudo tumors of the lung after lung volume reduction surgery.

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    Oey, Inger F; Jeyapalan, Kanagaratnam; Entwisle, James J; Waller, David A

    2004-03-01

    We describe 2 patients who underwent lung volume reduction surgery, who postoperatively had computed tomographic scans that showed symptomatic mass lesions suggestive of malignancy and an inhaled foreign body. Investigations excluded these conditions with the remaining likely diagnosis of pseudotumor secondary to buttressing material. These potential sequelae of lung volume reduction surgery should be recognized in follow-up investigations.

  11. Estimation of gas and tissue lung volumes by MRI: functional approach of lung imaging.

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    Qanadli, S D; Orvoen-Frija, E; Lacombe, P; Di Paola, R; Bittoun, J; Frija, G

    1999-01-01

    The purpose of this work was to assess the accuracy of MRI for the determination of lung gas and tissue volumes. Fifteen healthy subjects underwent MRI of the thorax and pulmonary function tests [vital capacity (VC) and total lung capacity (TLC)] in the supine position. MR examinations were performed at inspiration and expiration. Lung volumes were measured by a previously validated technique on phantoms. Both individual and total lung volumes and capacities were calculated. MRI total vital capacity (VC(MRI)) was compared with spirometric vital capacity (VC(SP)). Capacities were correlated to lung volumes. Tissue volume (V(T)) was estimated as the difference between the total lung volume at full inspiration and the TLC. No significant difference was seen between VC(MRI) and VC(SP). Individual capacities were well correlated (r = 0.9) to static volume at full inspiration. The V(T) was estimated to be 836+/-393 ml. This preliminary study demonstrates that MRI can accurately estimate lung gas and tissue volumes. The proposed approach appears well suited for functional imaging of the lung.

  12. Spirometry, Static Lung Volumes, and Diffusing Capacity.

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    Vaz Fragoso, Carlos A; Cain, Hilary C; Casaburi, Richard; Lee, Patty J; Iannone, Lynne; Leo-Summers, Linda S; Van Ness, Peter H

    2017-09-01

    Spirometric Z-scores from the Global Lung Initiative (GLI) rigorously account for age-related changes in lung function and are thus age-appropriate when establishing spirometric impairments, including a restrictive pattern and air-flow obstruction. However, GLI-defined spirometric impairments have not yet been evaluated regarding associations with static lung volumes (total lung capacity [TLC], functional residual capacity [FRC], and residual volume [RV]) and gas exchange (diffusing capacity). We performed a retrospective review of pulmonary function tests in subjects ≥40 y old (mean age 64.6 y), including pre-bronchodilator measures for: spirometry ( n = 2,586), static lung volumes by helium dilution with inspiratory capacity maneuver ( n = 2,586), and hemoglobin-adjusted single-breath diffusing capacity ( n = 2,508). Using multivariable linear regression, adjusted least-squares means (adj LS Means) were calculated for TLC, FRC, RV, and hemoglobin-adjusted single-breath diffusing capacity. The adj LS Means were expressed with and without height-cubed standardization and stratified by GLI-defined spirometry, including normal ( n = 1,251), restrictive pattern ( n = 663), and air-flow obstruction (mild, [ n = 128]; moderate, [ n = 150]; and severe, [ n = 394]). Relative to normal spirometry, restrictive-pattern had lower adj LS Means for TLC, FRC, RV, and hemoglobin-adjusted single-breath diffusing capacity ( P ≤ .001). Conversely, relative to normal spirometry, mild, moderate, and severe air-flow obstruction had higher adj LS Means for FRC and RV ( P < .001). However, only mild and moderate air-flow obstruction had higher adj LS Means for TLC ( P < .001), while only moderate and severe air-flow obstruction had higher adj LS Means for RV/TLC ( P < .001) and lower adj LS Means for hemoglobin-adjusted single-breath diffusing capacity ( P < .001). Notably, TLC (calculated as FRC + inspiratory capacity) was not increased in severe air-flow obstruction ( P ≥ .11

  13. Lung volume recruitment in multiple sclerosis.

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    Nadim Srour

    Full Text Available INTRODUCTION: Pulmonary function abnormalities have been described in multiple sclerosis including reductions in forced vital capacity (FVC and cough but the time course of this impairment is unknown. Peak cough flow (PCF is an important parameter for patients with respiratory muscle weakness and a reduced PCF has a direct impact on airway clearance and may therefore increase the risk of respiratory tract infections. Lung volume recruitment is a technique that improves PCF by inflating the lungs to their maximal insufflation capacity. OBJECTIVES: Our goals were to describe the rate of decline of pulmonary function and PCF in patients with multiple sclerosis and describe the use of lung volume recruitment in this population. METHODS: We reviewed all patients with multiple sclerosis referred to a respiratory neuromuscular rehabilitation clinic from February 1999 until December 2010. Lung volume recruitment was attempted in patients with FVC <80% predicted. Regular twice daily lung volume recruitment was prescribed if it resulted in a significant improvement in the laboratory. RESULTS: There were 79 patients included, 35 of whom were seen more than once. A baseline FVC <80% predicted was present in 82% of patients and 80% of patients had a PCF insufficient for airway clearance. There was a significant decline in FVC (122.6 mL/y, 95% CI 54.9-190.3 and PCF (192 mL/s/y, 95% 72-311 over a median follow-up time of 13.4 months. Lung volume recruitment was associated with a slower decline in FVC (p<0.0001 and PCF (p = 0.042. CONCLUSION: Pulmonary function and cough decline significantly over time in selected patients with multiple sclerosis and lung volume recruitment is associated with a slower rate of decline in lung function and peak cough flow. Given design limitations, additional studies are needed to assess the role of lung volume recruitment in patients with multiple sclerosis.

  14. Lung lobar volume in patients with chronic interstitial pneumonia

    International Nuclear Information System (INIS)

    Harada, Hisao; Koba, Hiroyuki; Saitoh, Tsukasa; Abe, Shosaku.

    1997-01-01

    We measured lung lobar volume by using helical computed tomography (HCT) in 23 patients with idiopathic interstitial pneumonia (IIP), 7 patients with chronic interstitial pneumonia associated with collagen vascular disease (CVD-IP), and 5 healthy volunteers HCT scanning was done at the maximal inspiratory level and the resting end-expiratory level. To measure lung lobar volume, we traced the lobar margin on HCT images with a digitizer and calculated the lobar volume with a personal computer. The lower lobar volume and several factors influencing it in chronic interstitial pneumonia were studied. At the maximal inspiratory level, the lower lobar volume as a percent of the whole lung volume was 46.8±4.13% (mean ± SD) in the volunteers, 39.5±6.19% in the patients with IIP, and 27.7±7. 86% in the patients with CVD-IP. The lower lobar volumes in the patients were significantly lower than in the volunteers. Patients with IIP in whom autoantibody tests were positive had lower lobar volumes that were very low and were similar to those of patients with CVD-IP. These data suggest that collagen vascular disease may develop in patients with interstitial pneumonia. The patients with IIP who had emphysematous changes on the CT scans had smaller decreases in total lung capacity and lower ratios of forced expiratory volume in one second to forced vital capacity than did those who had no emphysematous changes, those two groups did not differ in the ratio of lower lobar volume to whole lung volume. This suggests that emphysematous change is not factor influencing lower lobar volume in patients with chronic interstitial pneumonia. We conclude that chronic interstitial pneumonia together with very low values for lower lobar volume may be a pulmonary manifestation of collagen vascular disease. (author)

  15. Lung volume reduction surgery for diffuse emphysema.

    Science.gov (United States)

    van Agteren, Joseph Em; Carson, Kristin V; Tiong, Leong Ung; Smith, Brian J

    2016-10-14

    Lung volume reduction surgery (LVRS) performed to treat patients with severe diffuse emphysema was reintroduced in the nineties. Lung volume reduction surgery aims to resect damaged emphysematous lung tissue, thereby increasing elastic properties of the lung. This treatment is hypothesised to improve long-term daily functioning and quality of life, although it may be costly and may be associated with risks of morbidity and mortality. Ten years have passed since the last version of this review was prepared, prompting us to perform an update. The objective of this review was to gather all available evidence from randomised controlled trials comparing the effectiveness of lung volume reduction surgery (LVRS) versus non-surgical standard therapy in improving health outcomes for patients with severe diffuse emphysema. Secondary objectives included determining which subgroup of patients benefit from LVRS and for which patients LVRS is contraindicated, to establish the postoperative complications of LVRS and its morbidity and mortality, to determine which surgical approaches for LVRS are most effective and to calculate the cost-effectiveness of LVRS. We identified RCTs by using the Cochrane Airways Group Chronic Obstructive Pulmonary Disease (COPD) register, in addition to the online clinical trials registers. Searches are current to April 2016. We included RCTs that studied the safety and efficacy of LVRS in participants with diffuse emphysema. We excluded studies that investigated giant or bullous emphysema. Two independent review authors assessed trials for inclusion and extracted data. When possible, we combined data from more than one study in a meta-analysis using RevMan 5 software. We identified two new studies (89 participants) in this updated review. A total of 11 studies (1760 participants) met the entry criteria of the review, one of which accounted for 68% of recruited participants. The quality of evidence ranged from low to moderate owing to an unclear risk

  16. Lung volume reduction for emphysema

    NARCIS (Netherlands)

    Shah, Pallav L.; Herth, Felix J.; van Geffen, Wouter H.; Deslee, Gaetan; Slebos, Dirk-Jan

    Advanced emphysema is a lung disease in which alveolar capillary units are destroyed and supporting tissue is lost. The combined effect of reduced gas exchange and changes in airway dynamics impairs expiratory airflow and leads to progressive air trapping. Pharmacological therapies have limited

  17. Calculated Atomic Volumes of the Actinide Metals

    DEFF Research Database (Denmark)

    Skriver, H.; Andersen, O. K.; Johansson, B.

    1979-01-01

    The equilibrium atomic volume is calculated for the actinide metals. It is possible to account for the localization of the 5f electrons taking place in americium.......The equilibrium atomic volume is calculated for the actinide metals. It is possible to account for the localization of the 5f electrons taking place in americium....

  18. Monte Carlo dose calculation of microbeam in a lung phantom

    International Nuclear Information System (INIS)

    Company, F.Z.; Mino, C.; Mino, F.

    1998-01-01

    Full text: Recent advances in synchrotron generated X-ray beams with high fluence rate permit investigation of the application of an array of closely spaced, parallel or converging microplanar beams in radiotherapy. The proposed techniques takes advantage of the hypothesised repair mechanism of capillary cells between alternate microbeam zones, which regenerates the lethally irradiated endothelial cells. The lateral and depth doses of 100 keV microplanar beams are investigated for different beam dimensions and spacings in a tissue, lung and tissue/lung/tissue phantom. The EGS4 Monte Carlo code is used to calculate dose profiles at different depth and bundles of beams (up to 20x20cm square cross section). The maximum dose on the beam axis (peak) and the minimum interbeam dose (valley) are compared at different depths, bundles, heights, widths and beam spacings. Relatively high peak to valley ratios are observed in the lung region, suggesting an ideal environment for microbeam radiotherapy. For a single field, the ratio at the tissue/lung interface will set the maximum dose to the target volume. However, in clinical application, several fields would be involved allowing much greater doses to be applied for the elimination of cancer cells. We conclude therefore that multifield microbeam therapy has the potential to achieve useful therapeutic ratios for the treatment of lung cancer

  19. Measurement of lung fluid volumes and albumin exclusion in sheep

    International Nuclear Information System (INIS)

    Pou, N.A.; Roselli, R.J.; Parker, R.E.; Clanton, J.A.; Harris, T.R.

    1989-01-01

    A radioactive tracer technique was used to determine interstitial diethylenetriaminepentaacetic acid (DTPA) and albumin distribution volume in sheep lungs. 125 I- and/or 131 I-labeled albumin were injected intravenously and allowed to equilibrate for 24 h. 99m Tc-labeled DTPA and 51 Cr-labeled erythrocytes were injected and allowed to equilibrate (2 h and 15 min, respectively) before a lethal dose of thiamylal sodium. Two biopsies (1-3 g) were taken from each lung and the remaining tissue was homogenized for wet-to-dry lung weight and volume calculations. Estimates of distribution volumes from whole lung homogenized samples were statistically smaller than biopsy samples for extravascular water, interstitial 99m Tc-DTPA, and interstitial albumin. The mean fraction of the interstitium (Fe), which excludes albumin, was 0.68 +/- 0.04 for whole lung samples compared with 0.62 +/- 0.03 for biopsy samples. Hematocrit may explain the consistent difference. To make the Fe for biopsy samples match that for homogenized samples, a mean hematocrit, which was 82% of large vessel hematocrit, was required. Excluded volume fraction for exogenous sheep albumin was compared with that of exogenous human albumin in two sheep, and no difference was found at 24 h

  20. SU-E-J-249: Correlation of Mean Lung Ventilation Value with Ratio of Total Lung Volumes

    International Nuclear Information System (INIS)

    Yu, N; Qu, H; Xia, P

    2014-01-01

    Purpose: Lung ventilation function measured from 4D-CT and from breathing correlated CT images is a novel concept to incorporate the lung physiologic function into treatment planning of radiotherapy. The calculated ventilation functions may vary from different breathing patterns, affecting evaluation of the treatment plans. The purpose of this study is to correlate the mean lung ventilation value with the ratio of the total lung volumes obtained from the relevant CTs. Methods: A ventilation map was calculated from the variations of voxel-to-voxel CT densities from two breathing phases from either 4D-CT or breathing correlated CTs. An open source image registration tool of Plastimatch was used to deform the inhale phase images to the exhale phase images. To calculate the ventilation map inside lung, the whole lung was delineated and the tissue outside the lung was masked out. With a software tool developed in house, the 3D ventilation map was then converted in the DICOM format associated with the planning CT images. The ventilation map was analyzed on a clinical workstation. To correlate ventilation map thus calculated with lung volume change, the total lung volume change was compared the mean ventilation from our method. Results: Twenty two patients who underwent stereotactic body irradiation for lung cancer was selected for this retrospective study. For this group of patients, the ratio of lung volumes for the inhale (Vin ) and exhale phase (Vex ) was shown to be linearly related to the mean of the local ventilation (Vent), Vin/Vex=1.+0.49*Vent (R2=0.93, p<0.01). Conclusion: The total lung volume change is highly correlated with the mean of local ventilation. The mean of local ventilation may be useful to assess the patient's lung capacity

  1. Measurement of lung volumes : usefulness of spiral CT

    International Nuclear Information System (INIS)

    Kang, Ho Yeong; Kwak, Byung Kook; Lee, Sang Yoon; Kim, Soo Ran; Lee, Shin Hyung; Lee, Chang Joon; Park, In Won

    1996-01-01

    To evaluate the usefulness of spiral CT in the measurement of lung volumes. Fifteen healthy volunteers were studied by both spirometer and spiral CT at full inspiration and expiration in order to correlated their results, including total lung capacity (TLC), vital capacity (VC) and residual volume (RV). 3-D images were reconstructed from spiral CT, and we measured lung volumes at a corresponding CT window range ; their volumes were compared with the pulmonary function test (paired t-test). The window range corresponding to TLC was from -1000HU to -150HU (p=0.279, r=0.986), and for VC from -910HU to -800HU (p=0.366, r=0.954) in full-inspiratory CT. The optimal window range for RV in full-expiratory CT was from -1000HU to -450HU (p=0.757, r=0.777), and TLC-VC in full-inspiratory CT was also calculated (p=0.843, r=0.847). Spiral CT at full inspiration can used to lung volumes such as TLC, VC and RV

  2. Lung volume reduction in chronic obstructive pulmonary disease ...

    African Journals Online (AJOL)

    Lung volume reduction in chronic obstructive pulmonary disease. ... loss to improve pulmonary mechanics and compliance, thereby reducing the work of breathing. ... of obtaining similar functional advantages to surgical lung volume reduction, ...

  3. Lung Volume Reduction After Stereotactic Ablative Radiation Therapy of Lung Tumors: Potential Application to Emphysema

    Energy Technology Data Exchange (ETDEWEB)

    Binkley, Michael S. [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Shrager, Joseph B. [Division of Thoracic Surgery, Department of Cardiothoracic Surgery, Stanford University School of Medicine, Stanford, California (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California (United States); Leung, Ann N. [Department of Radiology, Stanford University School of Medicine, Stanford, California (United States); Popat, Rita [Department of Health Research and Policy, Stanford University School of Medicine, Stanford, California (United States); Trakul, Nicholas [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Department of Radiation Oncology, University of Southern California Keck School of Medicine, Los Angeles, California (United States); Atwood, Todd F.; Chaudhuri, Aadel [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Maxim, Peter G. [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California (United States); Diehn, Maximilian, E-mail: Diehn@Stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California (United States); Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, California (United States); Loo, Billy W., E-mail: BWLoo@Stanford.edu [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, California (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, California (United States)

    2014-09-01

    Purpose: Lung volume reduction surgery (LVRS) improves dyspnea and other outcomes in selected patients with severe emphysema, but many have excessive surgical risk for LVRS. We analyzed the dose-volume relationship for lobar volume reduction after stereotactic ablative radiation therapy (SABR) of lung tumors, hypothesizing that SABR could achieve therapeutic volume reduction if applied in emphysema. Methods and Materials: We retrospectively identified patients treated from 2007 to 2011 who had SABR for 1 lung tumor, pre-SABR pulmonary function testing, and ≥6 months computed tomographic (CT) imaging follow-up. We contoured the treated lobe and untreated adjacent lobe(s) on CT before and after SABR and calculated their volume changes relative to the contoured total (bilateral) lung volume (TLV). We correlated lobar volume reduction with the volume receiving high biologically effective doses (BED, α/β = 3). Results: 27 patients met the inclusion criteria, with a median CT follow-up time of 14 months. There was no grade ≥3 toxicity. The median volume reduction of the treated lobe was 4.4% of TLV (range, −0.4%-10.8%); the median expansion of the untreated adjacent lobe was 2.6% of TLV (range, −3.9%-11.6%). The volume reduction of the treated lobe was positively correlated with the volume receiving BED ≥60 Gy (r{sup 2}=0.45, P=.0001). This persisted in subgroups determined by high versus low pre-SABR forced expiratory volume in 1 second, treated lobe CT emphysema score, number of fractions, follow-up CT time, central versus peripheral location, and upper versus lower lobe location, with no significant differences in effect size between subgroups. Volume expansion of the untreated adjacent lobe(s) was positively correlated with volume reduction of the treated lobe (r{sup 2}=0.47, P<.0001). Conclusions: We identified a dose-volume response for treated lobe volume reduction and adjacent lobe compensatory expansion after lung tumor SABR, consistent across

  4. Comparison of actual tidal volume in neonatal lung model volume control ventilation using three ventilators.

    Science.gov (United States)

    Toyama, H; Endo, Y; Ejima, Y; Matsubara, M; Kurosawa, S

    2011-07-01

    In neonates, small changes in tidal volumes (V(T)) may lead to complications. Previous studies have shown a significant difference between ventilator-measured tidal volume and tidal volume delivered (actual V(T)). We evaluated the accuracy of three different ventilators to deliver small V(T) during volume-controlled ventilation. We tested Servo 300, 840 ventilator and Evita 4 Neoflow ventilators with lung models simulating normal and injured neonatal lung compliance models. Gas volume delivered from the ventilator into the test circuit (V(TV)) and actual V(T) to the test lung were measured using Ventrak respiration monitors at set V(T) (30 ml). The gas volume increase of the breathing circuit was then calculated. Tidal volumes of the SV300 and PB840 in both lung models were similar to the set V(T) and the actual tidal volumes in the injured model (20.7 ml and 19.8 ml, respectively) were significantly less than that in the normal model (27.4 ml and 23.4 ml). PB840 with circuit compliance compensation could not improve the actual V(T). V(TV) of the EV4N in the normal and the injured models (37.8 ml and 46.6 ml) were markedly increased compared with set V(T), and actual V(T) were similar to set V(T) in the normal and injured model (30.2 ml and 31.9 ml, respectively). EV4N measuring V(T) close to the lung could match actual V(T) to almost the same value as the set V(T) however the gas volume of the breathing circuit was increased. If an accurate value for the patient's actual V(T) is needed, this V(T) must be measured by a sensor located between the Y-piece and the tracheal tube.

  5. Lung lesion doubling times: values and variability based on method of volume determination

    International Nuclear Information System (INIS)

    Eisenbud Quint, Leslie; Cheng, Joan; Schipper, Matthew; Chang, Andrew C.; Kalemkerian, Gregory

    2008-01-01

    Purpose: To determine doubling times (DTs) of lung lesions based on volumetric measurements from thin-section CT imaging. Methods: Previously untreated patients with ≥ two thin-section CT scans showing a focal lung lesion were identified. Lesion volumes were derived using direct volume measurements and volume calculations based on lesion area and diameter. Growth rates (GRs) were compared by tissue diagnosis and measurement technique. Results: 54 lesions were evaluated including 8 benign lesions, 10 metastases, 3 lymphomas, 15 adenocarcinomas, 11 squamous carcinomas, and 7 miscellaneous lung cancers. Using direct volume measurements, median DTs were 453, 111, 15, 181, 139 and 137 days, respectively. Lung cancer DTs ranged from 23-2239 days. There were no significant differences in GRs among the different lesion types. There was considerable variability among GRs using different volume determination methods. Conclusions: Lung cancer doubling times showed a substantial range, and different volume determination methods gave considerably different DTs

  6. [Target volume margins for lung cancer: internal target volume/clinical target volume].

    Science.gov (United States)

    Jouin, A; Pourel, N

    2013-10-01

    The aim of this study was to carry out a review of margins that should be used for the delineation of target volumes in lung cancer, with a focus on margins from gross tumour volume (GTV) to clinical target volume (CTV) and internal target volume (ITV) delineation. Our review was based on a PubMed literature search with, as a cornerstone, the 2010 European Organisation for Research and Treatment of Cancer (EORTC) recommandations by De Ruysscher et al. The keywords used for the search were: radiotherapy, lung cancer, clinical target volume, internal target volume. The relevant information was categorized under the following headings: gross tumour volume definition (GTV), CTV-GTV margin (first tumoural CTV then nodal CTV definition), in field versus elective nodal irradiation, metabolic imaging role through the input of the PET scanner for tumour target volume and limitations of PET-CT imaging for nodal target volume definition, postoperative radiotherapy target volume definition, delineation of target volumes after induction chemotherapy; then the internal target volume is specified as well as tumoural mobility for lung cancer and respiratory gating techniques. Finally, a chapter is dedicated to planning target volume definition and another to small cell lung cancer. For each heading, the most relevant and recent clinical trials and publications are mentioned. Copyright © 2013. Published by Elsevier SAS.

  7. The effect of minimally invasive surgical repair on the lung volumes of patients with pectus excavatum.

    Science.gov (United States)

    Sengul, Aysen Taslak; Sahin, Bunyamin; Celenk, Cetin; Basoglu, Ahmet; Sengul, Bilal

    2014-04-01

    To assess the increase in lung volume after Nuss surgery in patients with pectus excavatum (PE) by using stereological methods and to evaluate the correlation between the lung volume and spirometry findings. Twenty patients, treated for PE between 2008 and 2010, were evaluated prospectively. They underwent preoperative chest radiography, computed thorax tomography (CTT), and spirometry. Thereafter, the Haller index was calculated for each patient. In the third postoperative month, CTT and spirometry were repeated.Lung volumes and volume fractions were evaluated using CTT images, applying the Cavalieri principle for stereological methods. Then the correlation between the pre- and postoperative values of the lung volumes with spirometry findings was determined. Volumes of the right and left lungs were calculated stereologically, using CTT images. Postoperative volume increase of ∼417.6 ± 747.6 mL was detected. The maximum volume increase was observed in the left lung. In the postoperative period, the total volume increase and the volume increase detected in the left lung were found to be statistically significant (p volume in 1 second, and forced expiratory flow 25 to 75% were 0.67, 0.68, and 0.61, respectively; the postoperative r figures were 0.43, 0.42, and 0.35, respectively. Although there was a strong correlation between the preoperative lung volume and spirometry findings (p volume and spirometry findings (p > 0.05). Postoperative pulmonary volume increase occurs in patients with PE after Nuss surgery. However, postoperative spirometry findings may not reflect morphological improvement because pain restricts thoracic movements. Therefore, in patients with PE, quantitative evaluation of the results of surgical repair is possible using the CTT images through a combination of stereological methods. Georg Thieme Verlag KG Stuttgart · New York.

  8. Body mass index and dynamic lung volumes in office workers

    International Nuclear Information System (INIS)

    Rasool, S.A.; Shirwany, A.K.

    2012-01-01

    To measure the association of body mass index (BMI) to lung volumes assessed by spirometer. Study Design: Cross-sectional analytical study. Place and Duration of Study: Department of Physiology and Cell Biology, University of Health Sciences, Lahore, from February to August 2009. Methodology: Two hundred and twenty-five apparently healthy adult office workers of either gender aged > 20 years were recruited. Height and weight were measured and BMI was calculated as kg/m2. Subjects were categorized as normal (BMI=18.5 to 24.9 kg/m2); overweight (BMI=25 to 29.9 kg/m2); and obese Class 1 (BMI=30 to 34.9 kg/m2) on the basis of BMI. Lung volumes were measured by digital spirometer and were reported as percentage of predicted values for forced vital capacity (FVC%), forced expiratory volume in first second (FEV1%) and ratio of FEV1 to FVC (FEV1:FVC). Groups were compared using t-test and ANOVA, correlation was assessed by Pearson's 'r'. Results: Significant differences in lung volumes were found in different BMI categories. Obese subjects had significantly lower FVC% (p < 0.0001), as well as significantly lower FEV1% (p = 0.003) as compared to normal subjects. There were significant linear relationships between obesity and PFTs. BMI had significant negative linear association with FVC% in overweight (r = -0.197) and obese (r = - 0.488); and with FEV1% in obese subjects (r = -0.510). Gender and age had no significant effect on mean values of PFTs. Conclusion: Obese individuals in this sample had significant decline in lung volumes. (author)

  9. Lung volume reduction surgery in bronchopulmonary dysplasia.

    Science.gov (United States)

    Siaplaouras, J; Heckmann, M; Reiss, I; Schaible, T; Waag, K L; Gortner, L

    2003-06-01

    We report on a female preterm infant of 29 wk gestational age, who developed acquired lobar emphysema after prolonged artificial ventilation secondary to respiratory disease syndrome and bronchopulmonary dysplasia. The infant underwent atypical segmentectomy at the age of 12 mo because of life-threatening hypoxaemia with pulmonary hypertension and failure of conservative treatment. Lung volume reduction surgery (LVRS) dramatically improved the respiratory function and resulted in adequate weight gain and psychomotor development. In selected cases LVRS can be an option for lobar emphysema in premature infants with severe bronchopulmonary dysplasia.

  10. Update on Nonsurgical Lung Volume Reduction Procedures

    Directory of Open Access Journals (Sweden)

    J. Alberto Neder

    2016-01-01

    Full Text Available There has been a surge of interest in endoscopic lung volume reduction (ELVR strategies for advanced COPD. Valve implants, coil implants, biological LVR (BioLVR, bronchial thermal vapour ablation, and airway stents are used to induce lung deflation with the ultimate goal of improving respiratory mechanics and chronic dyspnea. Patients presenting with severe air trapping (e.g., inspiratory capacity/total lung capacity (TLC 225% predicted and thoracic hyperinflation (TLC > 150% predicted have the greatest potential to derive benefit from ELVR procedures. Pre-LVRS or ELVR assessment should ideally include cardiological evaluation, high resolution CT scan, ventilation and perfusion scintigraphy, full pulmonary function tests, and cardiopulmonary exercise testing. ELVR procedures are currently available in selected Canadian research centers as part of ethically approved clinical trials. If a decision is made to offer an ELVR procedure, one-way valves are the first option in the presence of complete lobar exclusion and no significant collateral ventilation. When the fissure is not complete, when collateral ventilation is evident in heterogeneous emphysema or when emphysema is homogeneous, coil implants or BioLVR (in that order are the next logical alternatives.

  11. Emphysema. Imaging for endoscopic lung volume reduction

    International Nuclear Information System (INIS)

    Storbeck, B.; Oldigs, M.; Rabe, K.F.; Weber, C.; University Medical Center Hamburg-Eppendorf

    2015-01-01

    Chronic obstructive pulmonary disease (COPD) is characterized by two entities, the more airway-predominant type (''bronchitis'') on the one hand, and emphysema-predominant type on the other. Imaging via high-resolution computed tomography plays an important role in phenotyping COPD. For patients with advanced lung emphysema, new endoscopic lung volume reduction therapies (ELVR) have been developed. Proper selection of suitable patients requires thin-section reconstruction of volumetric CT image data sets also in coronal and sagittal orientation are required. In the current manuscript we will describe emphysema subtypes (centrilobular, paraseptal, panlobular), options for quantifying emphysema and this importance of regional distribution (homogeneous or heterogeneous, target area) as this is crucial for patient selection. Analysis of the interlobular fissures is obligatory despite the lack of standardization, as incomplete fissures indicate collateral ventilation (CV) via parenchymal bridges, which is an important criterion in choosing endoscopic methods of LVR. Every radiologist should be familiar with modern LVR therapies such as valves and coils, and furthermore should know what a lung doctor expects from radiologic evaluation (before and after ELVR). Finally we present a checklist as a quick reference for all steps concerning imaging for ELVR.

  12. Lung volume reduction surgery for emphysema.

    Science.gov (United States)

    Flaherty, K R; Martinez, F J

    2000-12-01

    Over the past decades, extensive literature has been published regarding surgical therapies for advanced COPD. Lung-volume reduction surgery would be an option for a significantly larger number of patients than classic bullectomy or lung transplantation. Unfortunately, the initial enthusiasm has been tempered by major questions regarding the optimal surgical approach, safety, firm selection criteria, and confirmation of long-term benefits. In fact, the long-term follow-up reported in patients undergoing classical bullectomy should serve to caution against unbridled enthusiasm for the indiscriminate application of LVRS. Those with the worst long-term outcome despite favourable short-term improvements after bullectomy have consistently been those with the lowest pulmonary function and significant emphysema in the remaining lung who appear remarkably similar to those being evaluated for LVRS. With this in mind, the National Heart, Lung and Blood Institute partnered with the Health Care Finance Administration to establish a multicenter, prospective, randomized study of intensive medical management, including pulmonary rehabilitation versus the same plus bilateral (by MS or VATS), known as the National Emphysema Treatment Trial. The primary objectives are to determine whether LVRS improves survival and exercise capacity. The secondary objectives will examine effects on pulmonary function and HRQL, compare surgical techniques, examine selection criteria for optimal response, identify criteria to determine those who are at prohibitive surgical risk, and examine long-term cost effectiveness. It is hoped that data collected from this novel, multicenter collaboration will place the role of LVRS in a clearer perspective for the physician caring for patients with advanced emphysema.

  13. EARTHWORK VOLUME CALCULATION FROM DIGITAL TERRAIN MODELS

    Directory of Open Access Journals (Sweden)

    JANIĆ Milorad

    2015-06-01

    Full Text Available Accurate calculation of cut and fill volume has an essential importance in many fields. This article shows a new method, which has no approximation, based on Digital Terrain Models. A relatively new mathematical model is developed for that purpose, which is implemented in the software solution. Both of them has been tested and verified in the praxis on several large opencast mines. This application is developed in AutoLISP programming language and works in AutoCAD environment.

  14. Lung volumes and emphysema in smokers with interstitial lung abnormalities.

    Science.gov (United States)

    Washko, George R; Hunninghake, Gary M; Fernandez, Isis E; Nishino, Mizuki; Okajima, Yuka; Yamashiro, Tsuneo; Ross, James C; Estépar, Raúl San José; Lynch, David A; Brehm, John M; Andriole, Katherine P; Diaz, Alejandro A; Khorasani, Ramin; D'Aco, Katherine; Sciurba, Frank C; Silverman, Edwin K; Hatabu, Hiroto; Rosas, Ivan O

    2011-03-10

    Cigarette smoking is associated with emphysema and radiographic interstitial lung abnormalities. The degree to which interstitial lung abnormalities are associated with reduced total lung capacity and the extent of emphysema is not known. We looked for interstitial lung abnormalities in 2416 (96%) of 2508 high-resolution computed tomographic (HRCT) scans of the lung obtained from a cohort of smokers. We used linear and logistic regression to evaluate the associations between interstitial lung abnormalities and HRCT measurements of total lung capacity and emphysema. Interstitial lung abnormalities were present in 194 (8%) of the 2416 HRCT scans evaluated. In statistical models adjusting for relevant covariates, interstitial lung abnormalities were associated with reduced total lung capacity (-0.444 liters; 95% confidence interval [CI], -0.596 to -0.292; Ppulmonary disease (COPD) (odds ratio, 0.53; 95% CI, 0.37 to 0.76; P<0.001). The effect of interstitial lung abnormalities on total lung capacity and emphysema was dependent on COPD status (P<0.02 for the interactions). Interstitial lung abnormalities were positively associated with both greater exposure to tobacco smoke and current smoking. In smokers, interstitial lung abnormalities--which were present on about 1 of every 12 HRCT scans--were associated with reduced total lung capacity and a lesser amount of emphysema. (Funded by the National Institutes of Health and the Parker B. Francis Foundation; ClinicalTrials.gov number, NCT00608764.).

  15. October 2015 Phoenix pulmonary journal club: lung volume reduction

    Directory of Open Access Journals (Sweden)

    Mathew M

    2015-11-01

    Full Text Available No abstract available. Article truncated at 150 words. The October 2015 pulmonary journal club focused on the review of older studies evaluating lung volume reduction surgery and how this has transitioned toward the development of non-surgical modes of lung volume reduction. The physiology behind dyspnea in chronic obstructive pulmonary disease (COPD is a complex process. One of the proposed mechanisms has been hyperinflation associated with air trapping. In the mid 1990s studies by Cooper and Peterson (1 offered a promising approach in which lung volume reduction (LVR could improve ventilatory mechanics and improve dyspnea. As the procedure gained more popularity, additional larger scale trials were performed to support its validity. We reviewed 2 studies looking at lung volume reduction. The first was "The Effect of Lung Volume Reduction Surgery In Patients With Severe Emphysema” (2 . This was a smaller, randomized controlled trial (RCT that looked at 2 groups of 24 patients. Once group received LVR while the ...

  16. Radiological evaluation of lung volume among Koreans with silicosis

    International Nuclear Information System (INIS)

    Rhee, Byung Chull

    1975-01-01

    1. Radiological evaluation of lung volumes was carried out thirty Korean males patients with silicosis, and following results were obtained. 2. The mean radiological lung volume among those patients was 7,587 ml. 3. When compared with the group of normal Korean male adults ranging from 31 to 55 years of age, the mean lung volume was increased by 2,346 ml. 4. The lung volume of these patients was even slightly larger than that of the group of Korean athletes of all ages. 5. On the other hand, the vital capacity in patients with silicosis was markedly diminished, the mean vital capacity being 2,909 ml. 6. The patients with silicosis also revealed emphysematous changes in the lung as well as increased residual volumes. The vital capacity was smallest in the latest stage.

  17. Lung Dose Calculation With SPECT/CT for {sup 90}Yittrium Radioembolization of Liver Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Naichang, E-mail: yun@ccf.org [Department of Radiation Oncology, Cleveland Clinic, Cleveland, OH (United States); Srinivas, Shaym M.; DiFilippo, Frank P.; Shrikanthan, Sankaran [Department of Nuclear Medicine, Cleveland Clinic, Cleveland, OH (United States); Levitin, Abraham; McLennan, Gordon; Spain, James [Department of Interventional Radiology, Cleveland Clinic, Cleveland, OH (United States); Xia, Ping; Wilkinson, Allan [Department of Radiation Oncology, Cleveland Clinic, Cleveland, OH (United States)

    2013-03-01

    Purpose: To propose a new method to estimate lung mean dose (LMD) using technetium-99m labeled macroaggregated albumin ({sup 99m}Tc-MAA) single photon emission CT (SPECT)/CT for {sup 90}Yttrium radioembolization of liver tumors and to compare the LMD estimated using SPECT/CT with clinical estimates of LMD using planar gamma scintigraphy (PS). Methods and Materials: Images of 71 patients who had SPECT/CT and PS images of {sup 99m}Tc-MAA acquired before TheraSphere radioembolization of liver cancer were analyzed retrospectively. LMD was calculated from the PS-based lung shunt assuming a lung mass of 1 kg and 50 Gy per GBq of injected activity shunted to the lung. For the SPECT/CT-based estimate, the LMD was calculated with the activity concentration and lung volume derived from SPECT/CT. The effect of attenuation correction and the patient's breathing on the calculated LMD was studied with the SPECT/CT. With these effects correctly taken into account in a more rigorous fashion, we compared the LMD calculated with SPECT/CT with the LMD calculated with PS. Results: The mean dose to the central region of the lung leads to a more accurate estimate of LMD. Inclusion of the lung region around the diaphragm in the calculation leads to an overestimate of LMD due to the misregistration of the liver activity to the lung from the patient's breathing. LMD calculated based on PS is a poor predictor of the actual LMD. For the subpopulation with large lung shunt, the mean overestimation from the PS method for the lung shunt was 170%. Conclusions: A new method of calculating the LMD for TheraSphere and SIR-Spheres radioembolization of liver cancer based on {sup 99m}Tc-MAA SPECT/CT is presented. The new method provides a more accurate estimate of radiation risk to the lungs. For patients with a large lung shunt calculated from PS, a recalculation of LMD based on SPECT/CT is recommended.

  18. Lung Dose Calculation With SPECT/CT for 90Yittrium Radioembolization of Liver Cancer

    International Nuclear Information System (INIS)

    Yu, Naichang; Srinivas, Shaym M.; DiFilippo, Frank P.; Shrikanthan, Sankaran; Levitin, Abraham; McLennan, Gordon; Spain, James; Xia, Ping; Wilkinson, Allan

    2013-01-01

    Purpose: To propose a new method to estimate lung mean dose (LMD) using technetium-99m labeled macroaggregated albumin ( 99m Tc-MAA) single photon emission CT (SPECT)/CT for 90 Yttrium radioembolization of liver tumors and to compare the LMD estimated using SPECT/CT with clinical estimates of LMD using planar gamma scintigraphy (PS). Methods and Materials: Images of 71 patients who had SPECT/CT and PS images of 99m Tc-MAA acquired before TheraSphere radioembolization of liver cancer were analyzed retrospectively. LMD was calculated from the PS-based lung shunt assuming a lung mass of 1 kg and 50 Gy per GBq of injected activity shunted to the lung. For the SPECT/CT-based estimate, the LMD was calculated with the activity concentration and lung volume derived from SPECT/CT. The effect of attenuation correction and the patient's breathing on the calculated LMD was studied with the SPECT/CT. With these effects correctly taken into account in a more rigorous fashion, we compared the LMD calculated with SPECT/CT with the LMD calculated with PS. Results: The mean dose to the central region of the lung leads to a more accurate estimate of LMD. Inclusion of the lung region around the diaphragm in the calculation leads to an overestimate of LMD due to the misregistration of the liver activity to the lung from the patient's breathing. LMD calculated based on PS is a poor predictor of the actual LMD. For the subpopulation with large lung shunt, the mean overestimation from the PS method for the lung shunt was 170%. Conclusions: A new method of calculating the LMD for TheraSphere and SIR-Spheres radioembolization of liver cancer based on 99m Tc-MAA SPECT/CT is presented. The new method provides a more accurate estimate of radiation risk to the lungs. For patients with a large lung shunt calculated from PS, a recalculation of LMD based on SPECT/CT is recommended

  19. Lung dose calculation with SPECT/CT for ⁹⁰Yittrium radioembolization of liver cancer.

    Science.gov (United States)

    Yu, Naichang; Srinivas, Shaym M; Difilippo, Frank P; Shrikanthan, Sankaran; Levitin, Abraham; McLennan, Gordon; Spain, James; Xia, Ping; Wilkinson, Allan

    2013-03-01

    To propose a new method to estimate lung mean dose (LMD) using technetium-99m labeled macroaggregated albumin ((99m)Tc-MAA) single photon emission CT (SPECT)/CT for (90)Yttrium radioembolization of liver tumors and to compare the LMD estimated using SPECT/CT with clinical estimates of LMD using planar gamma scintigraphy (PS). Images of 71 patients who had SPECT/CT and PS images of (99m)Tc-MAA acquired before TheraSphere radioembolization of liver cancer were analyzed retrospectively. LMD was calculated from the PS-based lung shunt assuming a lung mass of 1 kg and 50 Gy per GBq of injected activity shunted to the lung. For the SPECT/CT-based estimate, the LMD was calculated with the activity concentration and lung volume derived from SPECT/CT. The effect of attenuation correction and the patient's breathing on the calculated LMD was studied with the SPECT/CT. With these effects correctly taken into account in a more rigorous fashion, we compared the LMD calculated with SPECT/CT with the LMD calculated with PS. The mean dose to the central region of the lung leads to a more accurate estimate of LMD. Inclusion of the lung region around the diaphragm in the calculation leads to an overestimate of LMD due to the misregistration of the liver activity to the lung from the patient's breathing. LMD calculated based on PS is a poor predictor of the actual LMD. For the subpopulation with large lung shunt, the mean overestimation from the PS method for the lung shunt was 170%. A new method of calculating the LMD for TheraSphere and SIR-Spheres radioembolization of liver cancer based on (99m)Tc-MAA SPECT/CT is presented. The new method provides a more accurate estimate of radiation risk to the lungs. For patients with a large lung shunt calculated from PS, a recalculation of LMD based on SPECT/CT is recommended. Copyright © 2013 Elsevier Inc. All rights reserved.

  20. Indirect measurement of lung density and air volume from electrical impedance tomography (EIT) data.

    Science.gov (United States)

    Nebuya, Satoru; Mills, Gary H; Milnes, Peter; Brown, Brian H

    2011-12-01

    This paper describes a method for estimating lung density, air volume and changes in fluid content from a non-invasive measurement of the electrical resistivity of the lungs. Resistivity in Ω m was found by fitting measured electrical impedance tomography (EIT) data to a finite difference model of the thorax. Lung density was determined by comparing the resistivity of the lungs, measured at a relatively high frequency, with values predicted from a published model of lung structure. Lung air volume can then be calculated if total lung weight is also known. Temporal changes in lung fluid content will produce proportional changes in lung density. The method was implemented on EIT data, collected using eight electrodes placed in a single plane around the thorax, from 46 adult male subjects and 36 adult female subjects. Mean lung densities (±SD) of 246 ± 67 and 239 ± 64 kg m(-3), respectively, were obtained. In seven adult male subjects estimates of 1.68 ± 0.30, 3.42 ± 0.49 and 4.40 ± 0.53 l in residual volume, functional residual capacity and vital capacity, respectively, were obtained. Sources of error are discussed. It is concluded that absolute differences in lung density of about 30% and changes over time of less than 30% should be detected using the current technology in normal subjects. These changes would result from approximately 300 ml increase in lung fluid. The method proposed could be used for non-invasive monitoring of total lung air and fluid content in normal subjects but needs to be assessed in patients with lung disease.

  1. Effect of increases in lung volume on clearance of aerosolized solute from human lungs

    Energy Technology Data Exchange (ETDEWEB)

    Marks, J.D.; Luce, J.M.; Lazar, N.M.; Wu, J.N.; Lipavsky, A.; Murray, J.F.

    1985-10-01

    To study the effect of increases in lung volume on solute uptake, we measured clearance of /sup 99m/Tc-diethylenetriaminepentaacetic acid (Tc-DTPA) at different lung volumes in 19 healthy humans. Seven subjects inhaled aerosols (1 micron activity median aerodynamic diam) at ambient pressure; clearance and functional residual capacity (FRC) were measured at ambient pressure (control) and at increased lung volume produced by positive pressure (12 cmH2O continuous positive airway pressure (CPAP)) or negative pressure (voluntary breathing). Six different subjects inhaled aerosol at ambient pressure; clearance and FRC were measured at ambient pressure and CPAP of 6, 12, and 18 cmH2O pressure. Six additional subjects inhaled aerosol at ambient pressure or at CPAP of 12 cmH2O; clearance and FRC were determined at CPAP of 12 cmH2O. According to the results, Tc-DTPA clearance from human lungs is accelerated exponentially by increases in lung volume, this effect occurs whether lung volume is increased by positive or negative pressure breathing, and the effect is the same whether lung volume is increased during or after aerosol administration. The effect of lung volume must be recognized when interpreting the results of this method.

  2. Effect of increases in lung volume on clearance of aerosolized solute from human lungs

    International Nuclear Information System (INIS)

    Marks, J.D.; Luce, J.M.; Lazar, N.M.; Wu, J.N.; Lipavsky, A.; Murray, J.F.

    1985-01-01

    To study the effect of increases in lung volume on solute uptake, we measured clearance of /sup 99m/Tc-diethylenetriaminepentaacetic acid (Tc-DTPA) at different lung volumes in 19 healthy humans. Seven subjects inhaled aerosols (1 micron activity median aerodynamic diam) at ambient pressure; clearance and functional residual capacity (FRC) were measured at ambient pressure (control) and at increased lung volume produced by positive pressure [12 cmH 2 O continuous positive airway pressure (CPAP)] or negative pressure (voluntary breathing). Six different subjects inhaled aerosol at ambient pressure; clearance and FRC were measured at ambient pressure and CPAP of 6, 12, and 18 cmH 2 O pressure. Six additional subjects inhaled aerosol at ambient pressure or at CPAP of 12 cmH 2 O; clearance and FRC were determined at CPAP of 12 cmH 2 O. According to the results, Tc-DTPA clearance from human lungs is accelerated exponentially by increases in lung volume, this effect occurs whether lung volume is increased by positive or negative pressure breathing, and the effect is the same whether lung volume is increased during or after aerosol administration. The effect of lung volume must be recognized when interpreting the results of this method

  3. Estimation of lung volume and pulmonary blood volume from radioisotopic images

    International Nuclear Information System (INIS)

    Kanazawa, Minoru

    1989-01-01

    Lung volume and pulmonary blood volume in man were estimated from the radioisotopic image using single photon emission computed tomography (SPECT). Six healthy volunteers were studied in a supine position with normal and altered lung volumes by applying continuous negative body-surface pressure (CNP) and by positive end-expiratory pressure (PEEP). 99m Tc labeled human serum albumin was administered as an aerosol to image the lungs. The CNP caused the diaphragm to be lowered and it increased the mean lung tissue volume obtained by SPECT from 3.09±0.49 l for baseline to 3.67±0.62 l for 10 cmH 2 O (p 2 O (p 2 O), respectively. The PEEP also increased the lung tissue volume to 3.68±0.68 l for 10 cmH 2 O as compared with the baseline (p 2 O PEEP. The lung tissue volume obtained by SPECT showed a positive correlation with functional residual capacity measured by the He dilution method (r=0.91, p 99m Tc-labeled red blood cells. The L/H ratio decreased after either the CNP or PEEP, suggesting a decrease in the blood volume per unit lung volume. However, it was suggested that the total pulmonary blood volume increased slightly either on the CNP (+7.4% for 10 cmH 2 O, p 2 O,p<0.05) when we extrapolated the L/H ratio to the whole lungs by multiplying the lung tissue volume obtained by SPECT. We concluded that SPECT could offer access to the estimation of lung volume and pulmonary blood volume in vivo. (author)

  4. Lung volume reduction in chronic obstructive pulmonary disease

    African Journals Online (AJOL)

    compliance, thereby reducing the work of breathing. ... with the objective of obtaining similar functional advantages to surgical lung volume reduction, .... Any type of antiplatelet or anticoagulant therapy that cannot be discontinued for 7 days.

  5. Volume Adjustment of Lung Density by Computed Tomography Scans in Patients with Emphysema

    International Nuclear Information System (INIS)

    Shaker, S.B.; Dirksen, A.; Laursen, L.C.; Skovgaard, L.T.; Holstein-Rathlou, N.H.

    2004-01-01

    Purpose: To determine how to adjust lung density measurements for the volume of the lung calculated from computed tomography (CT) scans in patients with emphysema. Material and Methods: Fifty patients with emphysema underwent 3 CT scans at 2-week intervals. The scans were analyzed with a software package that detected the lung in contiguous images and subsequently generated a histogram of the pixel attenuation values. The total lung volume (TLV), lung weight, percentile density (PD), and relative area of emphysema (RA) were calculated from this histogram. RA and PD are commonly applied measures of pulmonary emphysema derived from CT scans. These parameters are markedly influenced by changes in the level of inspiration. The variability of lung density due to within-subject variation in TLV was explored by plotting TLV against PD and RA. Results: The coefficients for volume adjustment for PD were relatively stable over a wide range from the 10th to the 80th percentile, whereas for RA the coefficients showed large variability especially in the lower range, which is the most relevant for quantitation of pulmonary emphysema. Conclusion: Volume adjustment is mandatory in repeated CT densitometry and is more robust for PD than for RA. Therefore, PD seems more suitable for monitoring the progression of emphysema

  6. Fetal lung volume measurement by MRI with high-speed imaging systems

    Energy Technology Data Exchange (ETDEWEB)

    Osada, Hisao; Kaku, Kenshi [Chiba Univ. (Japan). Hospital

    2002-08-01

    Although ultrasonography is widely used for fetal morphologic observation, magnetic resonance imaging (MRI) has gained popularity as a new prenatal diagnostic method with recent introduction of high-speed imaging systems. Infants with lung hypoplasia affecting respiratory function require intensive management starting immediately after birth. Therefore, accurate prenatal differential diagnosis and severity evaluation are extremely important for these fetuses. The aim of this study is to measure fetal lung volume using a computer-based, three-dimensional MRI imaging system and to evaluate the possibility of clinical applications of this procedure. A total of 96 fetuses were evaluated, all were morphologically abnormal, and MRI was done for advanced assessment from 24 to 39 weeks gestation. Three-directional views of fetal chest were imaged by Signa Horizon, 1.5 Tesla, version 5.6 (General Electronics) with the following conditions; coil: TORSO coil, sequence: SSFSE (single shot fast spin echo), slice thickness: 5 mm, and imaging speed: 2 seconds/slice. To calculate the lung volume and create three-dimensional image, the lung area in each slice was traced out, then multiplied using computer image processing. Simultaneously, the volumes of all slices were summed to give the volume of each lung. Linear regression analysis and analysis of covariance (ANCOVA) were used for statistical analyses. In all cases, clear images were obtained, and were adequate for three-dimensional evaluation of the fetal lung. Thirty-five fetuses had poor outcomes, such as intrauterine fetal death, neonatal death, and intensive respiratory care. Regression lines of lung volume versus gestational week were calculated for these fetuses with poor outcome and 61 other fetuses with good outcome. ANCOVA, with gestational week as a covariant, revealed a significant intergroup difference in the lung volume (p<0.001). Similarly, regression lines of lung volume versus fetal body weight estimated by

  7. Accurate heterogeneous dose calculation for lung cancer patients without high‐resolution CT densities

    Science.gov (United States)

    Li, Jonathan G.; Liu, Chihray; Olivier, Kenneth R.; Dempsey, James F.

    2009-01-01

    The aim of this study was to investigate the relative accuracy of megavoltage photon‐beam dose calculations employing either five bulk densities or independent voxel densities determined by calibration of the CT Houndsfield number. Full‐resolution CT and bulk density treatment plans were generated for 70 lung or esophageal cancer tumors (66 cases) using a commercial treatment planning system with an adaptive convolution dose calculation algorithm (Pinnacle3, Philips Medicals Systems). Bulk densities were applied to segmented regions. Individual and population average densities were compared to the full‐resolution plan for each case. Monitor units were kept constant and no normalizations were employed. Dose volume histograms (DVH) and dose difference distributions were examined for all cases. The average densities of the segmented air, lung, fat, soft tissue, and bone for the entire set were found to be 0.14, 0.26, 0.89, 1.02, and 1.12 g/cm3, respectively. In all cases, the normal tissue DVH agreed to better than 2% in dose. In 62 of 70 DVHs of the planning target volume (PTV), agreement to better than 3% in dose was observed. Six cases demonstrated emphysema, one with bullous formations and one with a hiatus hernia having a large volume of gas. These required the additional assignment of density to the emphysemic lung and inflammatory changes to the lung, the regions of collapsed lung, the bullous formations, and the hernia gas. Bulk tissue density dose calculation provides an accurate method of heterogeneous dose calculation. However, patients with advanced emphysema may require high‐resolution CT studies for accurate treatment planning. PACS number: 87.53.Tf

  8. Entropy Production and the Pressure-Volume Curve of the Lung

    Directory of Open Access Journals (Sweden)

    Cláudio Lucas Oliveira

    2016-03-01

    Full Text Available We investigate analytically the production of entropy during a breathing cycle in healthy and diseased lungs. First, we calculate entropy production in healthy lungs by applying the laws of thermodynamics to the well-known transpulmonary pressure-volume (P-V curves of the lung under the assumption that lung tissue behaves as an entropy spring-like rubber. The bulk modulus, $B$, of the lung is also derived from these calculations. Second, we extend this approach to elastic recoil disorders of the lung such as occur in pulmonary fibrosis and emphysema. These diseases are characterized by particular alterations in the P-V relationship. For example, in fibrotic lungs B increases monotonically with disease progression, while in emphysema the opposite occurs. These diseases can thus be mimicked simply by making appropriate adjustments to the parameters of the P-V curve. Using Clausius's formalism, we show that entropy production, Delta_S, is related to the hysteresis area, Delta_A, enclosed by the P-V curve during a breathing cycle, namely, Delta_S = Delta_A/T, where T is the body temperature. Although Delta_A is highly dependent on the disease, such formula applies to healthy as well as diseased lungs, regardless of the disease stage. Finally, we use ansatzs to predict analytically the entropy produced by the fibrotic and emphysematous lungs.

  9. High lung volume increases stress failure in pulmonary capillaries

    Science.gov (United States)

    Fu, Z.; Costello, M. L.; Tsukimoto, K.; Prediletto, R.; Elliott, A. R.; Mathieu-Costello, O.; West, J. B.

    1992-01-01

    We previously showed that when pulmonary capillaries in anesthetized rabbits are exposed to a transmural pressure (Ptm) of approximately 40 mmHg, stress failure of the walls occurs with disruption of the capillary endothelium, alveolar epithelium, or sometimes all layers. The present study was designed to test whether stress failure occurred more frequently at high than at low lung volumes for the same Ptm. Lungs of anesthetized rabbits were inflated to a transpulmonary pressure of 20 cmH2O, perfused with autologous blood at 32.5 or 2.5 cmH2O Ptm, and fixed by intravascular perfusion. Samples were examined by both transmission and scanning electron microscopy. The results were compared with those of a previous study in which the lung was inflated to a transpulmonary pressure of 5 cmH2O. There was a large increase in the frequency of stress failure of the capillary walls at the higher lung volume. For example, at 32.5 cmH2O Ptm, the number of endothelial breaks per millimeter cell lining was 7.1 +/- 2.2 at the high lung volume compared with 0.7 +/- 0.4 at the low lung volume. The corresponding values for epithelium were 8.5 +/- 1.6 and 0.9 +/- 0.6. Both differences were significant (P less than 0.05). At 52.5 cmH2O Ptm, the results for endothelium were 20.7 +/- 7.6 (high volume) and 7.1 +/- 2.1 (low volume), and the corresponding results for epithelium were 32.8 +/- 11.9 and 11.4 +/- 3.7. At 32.5 cmH2O Ptm, the thickness of the blood-gas barrier was greater at the higher lung volume, consistent with the development of more interstitial edema. Ballooning of the epithelium caused by accumulation of edema fluid between the epithelial cell and its basement membrane was seen at 32.5 and 52.5 cmH2O Ptm. At high lung volume, the breaks tended to be narrower and fewer were oriented perpendicular to the axis of the pulmonary capillaries than at low lung volumes. Transmission and scanning electron microscopy measurements agreed well. Our findings provide a physiological

  10. Estimation of lung volumes from chest radiographs using shape information

    International Nuclear Information System (INIS)

    Pierce, R.J.; Brown, D.J.; Holmes, M.; Cumming, G.; Denison, D.M.

    1979-01-01

    The cross-sectional shapes of the chest and its contained structures were assessed in post-mortem anatomical sections and from computerised tomographic scans in living subjects. These shapes are described by simple equations that can be used to increase the accuracy of measuring lung volumes from chest radiographs. Radiographic estimates of total lung capacity, using the equations, were compared with plethysmographic and single-breath helium dilution measurements in 35 normal subjects. After correction for posture effects the radiographic estimates of TLC, which measure the displacement volume of the lung, exceeded the plethysmographic estimates of contained gas volume by a mean of 720 ml, which was taken as the volume of tissue, blood, and water in the lungs. The single-breath dilution estimates of TLC fell short of the plethysmographic values by a mean of 480 ml, taken as the volume of contained gas that was inaccessible to helium in 10 seconds. The tomographic studies suggested that the radiographic technique of measuring lung displacement volumes has an accuracy of +- 210 ml. The method is rapid and simple to use and the intra- and inter-observer variabilities of <1% and <5% respectively. (author)

  11. Quantitative assessment of irradiated lung volume and lung mass in breast cancer patients treated with tangential fields in combination with deep inspiration breath hold (DIBH)

    International Nuclear Information System (INIS)

    Kapp, Karin Sigrid; Zurl, Brigitte; Stranzl, Heidi; Winkler, Peter

    2010-01-01

    Purpose: Comparison of the amount of irradiated lung tissue volume and mass in patients with breast cancer treated with an optimized tangential-field technique with and without a deep inspiration breath-hold (DIBH) technique and its impact on the normal-tissue complication probability (NTCP). Material and Methods: Computed tomography datasets of 60 patients in normal breathing (NB) and subsequently in DIBH were compared. With a Real-Time Position Management Respiratory Gating System (RPM), anteroposterior movement of the chest wall was monitored and a lower and upper threshold were defined. Ipsilateral lung and a restricted tangential region of the lung were delineated and the mean and maximum doses calculated. Irradiated lung tissue mass was computed based on density values. NTCP for lung was calculated using a modified Lyman-Kutcher-Burman (LKB) model. Results: Mean dose to the ipsilateral lung in DIBH versus NB was significantly reduced by 15%. Mean lung mass calculation in the restricted area receiving ≤ 20 Gy (M 20 ) was reduced by 17% in DIBH but associated with an increase in volume. NTCP showed an improvement in DIBH of 20%. The correlation of individual breathing amplitude with NTCP proved to be independent. Conclusion: The delineation of a restricted area provides the lung mass calculation in patients treated with tangential fields. DIBH reduces ipsilateral lung dose by inflation so that less tissue remains in the irradiated region and its efficiency is supported by a decrease of NTCP. (orig.)

  12. Low Tidal Volume Reduces Lung Inflammation Induced by Liquid Ventilation in Piglets With Severe Lung Injury.

    Science.gov (United States)

    Jiang, Lijun; Feng, Huizhen; Chen, Xiaofan; Liang, Kaifeng; Ni, Chengyao

    2017-05-01

    Total liquid ventilation (TLV) is an alternative treatment for severe lung injury. High tidal volume is usually required for TLV to maintain adequate CO 2 clearance. However, high tidal volume may cause alveolar barotrauma. We aim to investigate the effect of low tidal volume on pulmonary inflammation in piglets with lung injury and under TLV. After the establishment of acute lung injury model by infusing lipopolysaccharide, 12 piglets were randomly divided into two groups, TLV with high tidal volume (25 mL/kg) or with low tidal volume (6 mL/kg) for 240 min, respectively. Extracorporeal CO 2 removal was applied in low tidal volume group to improve CO 2 clearance and in high tidal volume group as sham control. Gas exchange and hemodynamic status were monitored every 30 min during TLV. At the end of the study, pulmonary mRNA expression and plasmatic concentration of interleukin-6 (IL-6) and interleukin-8 (IL-8) were measured by collecting lung tissue and blood samples from piglets. Arterial blood pressure, PaO 2 , and PaCO 2 showed no remarkable difference between groups during the observation period. Compared with high tidal volume strategy, low tidal volume resulted in 76% reduction of minute volume and over 80% reduction in peak inspiratory pressure during TLV. In addition, low tidal volume significantly diminished pulmonary mRNA expression and plasmatic level of IL-6 and IL-8. We conclude that during TLV, low tidal volume reduces lung inflammation in piglets with acute lung injury without compromising gas exchange. © 2016 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  13. FCT (functional computed tomography) evaluation of the lung volumes at different PEEP (positive-end expiratory pressure) ventilation pattern, in mechanical ventilated patients

    International Nuclear Information System (INIS)

    Papi, M.G.; Di Segni, R.; Mazzetti, G.; Staffa, F.; Conforto, F.; Calimici, R.; Salvi, A.; Matteucci, G.

    2007-01-01

    Purpose To evaluate with FCT (functional computed tomography) total lung volume and fractional lung volumes at different PEEP (positive end expiratory pressure) values in acute mechanically ventilated patients. Methods Nine ICU (intensive care unity) patients (1 lung pneumonia, 2 polytrauma, 2 sepsis, 3 brain surgery, 1 pulmonary embolism); mean age 48 ± 15 years, 6 male, 3 female; GE 16 MDCT scan was performed with acquisition from apex to diaphragma in seven seca at different PEEP values. Raw CT data were analysed by an advantage workstation to obtain volume density masks and histograms of both lungs and each lung and these density ranges were applied: - 1000 - 950 hyper-ventilated lung, -900 - 650 well aerated lung, -950 - 500 all aerated lung, -500 + 200 lung tissue. Total and fractional lung volumes, Hounsfield unit (HU) were calculated and compared at different PEEP values (0, 5, 10, 15 cm H 2 O). In four patients lung volumes were compared between the more and the less involved lung at increased PEEP. Statistic analysis: comparison means-medians tests. Results Data calculated at five PEEP showed unexpected decrease of total lung volume and increase of lung density (HU); proportionally no significant improvement of oxigenation. (orig.)

  14. FCT (functional computed tomography) evaluation of the lung volumes at different PEEP (positive-end expiratory pressure) ventilation pattern, in mechanical ventilated patients

    Energy Technology Data Exchange (ETDEWEB)

    Papi, M.G.; Di Segni, R.; Mazzetti, G.; Staffa, F. [Dept. of Radiology, S. Giovanni HS, Rome (Italy); Conforto, F.; Calimici, R.; Salvi, A. [Dept. of Anesthesiology, S. Giovanni HS, Rome (Italy); Matteucci, G. [Dept. of Pneumology, S. Giovanni HS, Rome (Italy)

    2007-06-15

    Purpose To evaluate with FCT (functional computed tomography) total lung volume and fractional lung volumes at different PEEP (positive end expiratory pressure) values in acute mechanically ventilated patients. Methods Nine ICU (intensive care unity) patients (1 lung pneumonia, 2 polytrauma, 2 sepsis, 3 brain surgery, 1 pulmonary embolism); mean age 48 {+-} 15 years, 6 male, 3 female; GE 16 MDCT scan was performed with acquisition from apex to diaphragma in seven seca at different PEEP values. Raw CT data were analysed by an advantage workstation to obtain volume density masks and histograms of both lungs and each lung and these density ranges were applied: - 1000 - 950 = hyper-ventilated lung, -900 - 650 well aerated lung, -950 - 500 all aerated lung, -500 + 200 lung tissue. Total and fractional lung volumes, Hounsfield unit (HU) were calculated and compared at different PEEP values (0, 5, 10, 15 cm H{sub 2}O). In four patients lung volumes were compared between the more and the less involved lung at increased PEEP. Statistic analysis: comparison means-medians tests. Results Data calculated at five PEEP showed unexpected decrease of total lung volume and increase of lung density (HU); proportionally no significant improvement of oxigenation. (orig.)

  15. Lung Volume Reduction in Pulmonary Emphysema from the Radiologist's Perspective.

    Science.gov (United States)

    Doellinger, F; Huebner, R H; Kuhnigk, J M; Poellinger, A

    2015-08-01

    Pulmonary emphysema causes decrease in lung function due to irreversible dilatation of intrapulmonary air spaces, which is linked to high morbidity and mortality. Lung volume reduction (LVR) is an invasive therapeutical option for pulmonary emphysema in order to improve ventilation mechanics. LVR can be carried out by lung resection surgery or different minimally invasive endoscopical procedures. All LVR-options require mandatory preinterventional evaluation to detect hyperinflated dysfunctional lung areas as target structures for treatment. Quantitative computed tomography can determine the volume percentage of emphysematous lung and its topographical distribution based on the lung's radiodensity. Modern techniques allow for lobebased quantification that facilitates treatment planning. Clinical tests still play the most important role in post-interventional therapy monitoring, but CT is crucial in the detection of postoperative complications and foreshadows the method's high potential in sophisticated experimental studies. Within the last ten years, LVR with endobronchial valves has become an extensively researched minimally-invasive treatment option. However, this therapy is considerably complicated by the frequent occurrence of functional interlobar shunts. The presence of "collateral ventilation" has to be ruled out prior to valve implantations, as the presence of these extraanatomical connections between different lobes may jeopardize the success of therapy. Recent experimental studies evaluated the automatic detection of incomplete lobar fissures from CT scans, because they are considered to be a predictor for the existence of shunts. To date, these methods are yet to show acceptable results. Today, surgical and various minimal invasive methods of lung volume reduction are in use. Radiological and nuclear medical examinations are helpful in the evaluation of an appropriate lung area. Imaging can detect periinterventional complications. Reduction of lung

  16. [Lung volume reduction surgery for severe pulmonary emphysema in Iceland].

    Science.gov (United States)

    Gunnarsson, Sverrir I; Johannsson, Kristinn B; Guðjónsdóttir, Marta; Jónsson, Steinn; Beck, Hans J; Magnusson, Bjorn; Gudbjartsson, Tomas

    2011-12-01

    Lung volume reduction surgery (LVRS) can benefit patients with severe emphysema. The aim of this study was to evaluate the outcome of LVRS performed in Iceland. A prospective study of 16 consecutive patients who underwent bilateral LVRS through median sternotomy between January 1996 and December 2008. All patients had disabling dyspnea, lung hyperinflation, and emphysema with upper lobe predominance. Preoperatively all patients underwent pulmonary rehabilitation. Spirometry, lung volumes, arterial blood gases and exercise capacity were measured before and after surgery. Mean follow-up time was 8.7 years. Mean age was 59.2 ± 5.9 years. All patients had a history of heavy smoking. There was no perioperative mortality and survival was 100%, 93%, and 63% at 1, 5, and 10 years, respectively. The forced expiratory volume in 1 second (FEV1) and the forced vital capacity (FVC) improved significantly after surgery by 35% (plung capacity, residual volume and partial pressure of CO2 also showed statistically significant improvements but exercise capacity, O2 consumption and diffusing capacity of the lung for CO did not change. Prolonged air leak (≥ 7 days) was the most common complication (n=7). Five patients required reoperation, most commonly for sternal dehiscence (n=4). In this small prospective study, FEV1 and FVC increased and lung volumes and PaCO2 improved after LVRS. Long term survival was satisfactory although complications such as reoperations for sternal dehiscence were common and hospital stay therefore often prolonged.

  17. The effect of patient position and field configuration on lung volume in the treatment of advanced carcinoma of the breast or lung volumes in breast techniques - a case study

    International Nuclear Information System (INIS)

    Floyd, J.L.

    1989-01-01

    The position of the patient together with the configuration of the treatment fields play an important role in the volume of lung irradiated in breast techniques. These factors are even more important when the staging of the disease is advanced. A comparison of lung volumes is made with the patient in three treatment positions, and the effect of beam angling is demonstrated. A method of calculating the approximated lung volume from port films is proposed, together with a comparative analysis of the data obtained. Clinical decisions affecting technical considerations are examined. 6 refs., 5 figs

  18. Volume adjustment of lung density by computed tomography scans in patients with emphysema

    DEFF Research Database (Denmark)

    Shaker, S B; Dirksen, A; Laursen, Lars Christian

    2004-01-01

    of pulmonary emphysema derived from CT scans. These parameters are markedly influenced by changes in the level of inspiration. The variability of lung density due to within-subject variation in TLV was explored by plotting TLV against PD and RA. RESULTS: The coefficients for volume adjustment for PD were...... relatively stable over a wide range from the 10th to the 80th percentile, whereas for RA the coefficients showed large variability especially in the lower range, which is the most relevant for quantitation of pulmonary emphysema. CONCLUSION: Volume adjustment is mandatory in repeated CT densitometry......PURPOSE: To determine how to adjust lung density measurements for the volume of the lung calculated from computed tomography (CT) scans in patients with emphysema. MATERIAL AND METHODS: Fifty patients with emphysema underwent 3 CT scans at 2-week intervals. The scans were analyzed with a software...

  19. Influence of stapling the intersegmental planes on lung volume and function after segmentectomy.

    Science.gov (United States)

    Tao, Hiroyuki; Tanaka, Toshiki; Hayashi, Tatsuro; Yoshida, Kumiko; Furukawa, Masashi; Yoshiyama, Koichi; Okabe, Kazunori

    2016-10-01

    Dividing the intersegmental planes with a stapler during pulmonary segmentectomy leads to volume loss in the remnant segment. The aim of this study was to assess the influence of segment division methods on preserved lung volume and pulmonary function after segmentectomy. Using image analysis software on computed tomography (CT) images of 41 patients, the ratio of remnant segment and ipsilateral lung volume to their preoperative values (R-seg and R-ips) was calculated. The ratio of postoperative actual forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) per those predicted values based on three-dimensional volumetry (R-FEV1 and R-FVC) was also calculated. Differences in actual/predicted ratios of lung volume and pulmonary function for each of the division methods were analysed. We also investigated the correlations of the actual/predicted ratio of remnant lung volume with that of postoperative pulmonary function. The intersegmental planes were divided by either electrocautery or with a stapler in 22 patients and with a stapler alone in 19 patients. Mean values of R-seg and R-ips were 82.7 (37.9-140.2) and 104.9 (77.5-129.2)%, respectively. The mean values of R-FEV1 and R-FVC were 103.9 (83.7-135.1) and 103.4 (82.2-125.1)%, respectively. There were no correlations between the actual/predicted ratio of remnant lung volume and pulmonary function based on the division method. Both R-FEV1 and R-FVC were correlated not with R-seg, but with R-ips. Stapling does not lead to less preserved volume or function than electrocautery in the division of the intersegmental planes. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  20. [Comparison of dose calculation algorithms in stereotactic radiation therapy in lung].

    Science.gov (United States)

    Tomiyama, Yuki; Araki, Fujio; Kanetake, Nagisa; Shimohigashi, Yoshinobu; Tominaga, Hirofumi; Sakata, Jyunichi; Oono, Takeshi; Kouno, Tomohiro; Hioki, Kazunari

    2013-06-01

    Dose calculation algorithms in radiation treatment planning systems (RTPSs) play a crucial role in stereotactic body radiation therapy (SBRT) in the lung with heterogeneous media. This study investigated the performance and accuracy of dose calculation for three algorithms: analytical anisotropic algorithm (AAA), pencil beam convolution (PBC) and Acuros XB (AXB) in Eclipse (Varian Medical Systems), by comparison against the Voxel Monte Carlo algorithm (VMC) in iPlan (BrainLab). The dose calculations were performed with clinical lung treatments under identical planning conditions, and the dose distributions and the dose volume histogram (DVH) were compared among algorithms. AAA underestimated the dose in the planning target volume (PTV) compared to VMC and AXB in most clinical plans. In contrast, PBC overestimated the PTV dose. AXB tended to slightly overestimate the PTV dose compared to VMC but the discrepancy was within 3%. The discrepancy in the PTV dose between VMC and AXB appears to be due to differences in physical material assignments, material voxelization methods, and an energy cut-off for electron interactions. The dose distributions in lung treatments varied significantly according to the calculation accuracy of the algorithms. VMC and AXB are better algorithms than AAA for SBRT.

  1. A comparison of conventional surfactant treatment and partial liquid ventilation on the lung volume of injured ventilated small lungs

    International Nuclear Information System (INIS)

    Proquitté, Hans; Hartenstein, Sebastian; Wauer, Roland R; Schmalisch, Gerd; Koelsch, Uwe; Rüdiger, Mario

    2013-01-01

    As an alternative to surfactant therapy (ST), partial liquid ventilation (PLV) with perfluorocarbons (PFC) has been considered as a treatment for acute lung injury (ALI) in newborns. The instilled PFC is much heavier than the instilled surfactant and the aim of this study was to investigate whether PLV, compared to ST, increases the end-expiratory volume of the lung (V L ). Fifteen newborn piglets (age <12 h, mean weight 678 g) underwent saline lung lavage to achieve a surfactant depletion. Thereafter animals were randomized to PLV (n = 8), receiving PFC PF5080 (3M, Germany) at 30 mL kg −1 , and ST (n = 7) receiving 120 mg Curosurf®. Blood gases, hemodynamics and static compliance were measured initially (baseline), immediately after ALI, and after 240 min mechanical ventilation with either technique. Subsequently all piglets were killed; the lungs were removed in toto and frozen in liquid N 2 . After freeze-drying the lungs were cut into lung cubes (LCs) with edge lengths of 0.7 cm, to calculate V L . All LCs were weighed and the density of the dried lung tissue was calculated. No statistically significant differences between treatment groups PLV and ST (means ± SD) were noted in body weight (676 ± 16 g versus 679 ± 17 g; P = 0.974) or lung dry weight (1.64 ± 0.29 g versus 1.79 ± 0.48 g; P = 0.48). Oxygenation index and ventilatory efficacy index did not differ significantly between both groups at any time. V L (34.28 ± 6.13 mL versus 26.22 ± 8.1 mL; P < 0.05) and the density of the dried lung tissue (48.07 ± 5.02 mg mL −1 versus 69.07 ± 5.30 mg mL −1 ; P < 0.001), however, differed significantly between the PLV and ST groups. A 4 h PLV treatment of injured ventilated small lungs increased V L by 30% and decreased lung density by 31% compared to ST treatment, indicating greater lung distension after PLV compared to ST. (paper)

  2. A clinical study of lung cancer dose calculation accuracy with Monte Carlo simulation.

    Science.gov (United States)

    Zhao, Yanqun; Qi, Guohai; Yin, Gang; Wang, Xianliang; Wang, Pei; Li, Jian; Xiao, Mingyong; Li, Jie; Kang, Shengwei; Liao, Xiongfei

    2014-12-16

    The accuracy of dose calculation is crucial to the quality of treatment planning and, consequently, to the dose delivered to patients undergoing radiation therapy. Current general calculation algorithms such as Pencil Beam Convolution (PBC) and Collapsed Cone Convolution (CCC) have shortcomings in regard to severe inhomogeneities, particularly in those regions where charged particle equilibrium does not hold. The aim of this study was to evaluate the accuracy of the PBC and CCC algorithms in lung cancer radiotherapy using Monte Carlo (MC) technology. Four treatment plans were designed using Oncentra Masterplan TPS for each patient. Two intensity-modulated radiation therapy (IMRT) plans were developed using the PBC and CCC algorithms, and two three-dimensional conformal therapy (3DCRT) plans were developed using the PBC and CCC algorithms. The DICOM-RT files of the treatment plans were exported to the Monte Carlo system to recalculate. The dose distributions of GTV, PTV and ipsilateral lung calculated by the TPS and MC were compared. For 3DCRT and IMRT plans, the mean dose differences for GTV between the CCC and MC increased with decreasing of the GTV volume. For IMRT, the mean dose differences were found to be higher than that of 3DCRT. The CCC algorithm overestimated the GTV mean dose by approximately 3% for IMRT. For 3DCRT plans, when the volume of the GTV was greater than 100 cm(3), the mean doses calculated by CCC and MC almost have no difference. PBC shows large deviations from the MC algorithm. For the dose to the ipsilateral lung, the CCC algorithm overestimated the dose to the entire lung, and the PBC algorithm overestimated V20 but underestimated V5; the difference in V10 was not statistically significant. PBC substantially overestimates the dose to the tumour, but the CCC is similar to the MC simulation. It is recommended that the treatment plans for lung cancer be developed using an advanced dose calculation algorithm other than PBC. MC can accurately

  3. Quantitative study on lung volume and lung perfusion using SPECT and CT in thoracal tumors

    International Nuclear Information System (INIS)

    Beyer-Enke, S.A.; Goerich, J.; Strauss, L.G.

    1988-01-01

    22 patients with space occupying lesions in the thoracal region were investigated by computer tomography and by perfusion scintigraphy using SPECT. In order to evaluate the CT images quantitatively, the lung volume was determined using approximation method and compared with the perfusion in the SPECT study. For this, anatomically equivalent transaxial SPECT slices had been coordinated to the CT slices. Between the determined lung volumes and the activity in the ocrresponding layers, a statistically significant correlation was found. It could be shown that the stronger perfusion, frequently observed at the right side of the healthy lung, may be explained by an higher volume of the right pulmonary lobe. Whereas in benign displacing processes the relation activity to volume was similar to the one of the healthy lung, a strongly reduced perfusion together with inconspicuous lung volumes became apparent with malignant tumors. In addition to the great morphological evidence of CT and SPECT studies, additional informations regarding the dignity of displacing processes may be derived from the quantitative evaluation of both methods. (orig.) [de

  4. Endoscopic Lung Volume Reduction : An Expert Panel Recommendation - Update 2017

    NARCIS (Netherlands)

    Herth, Felix J. F.; Slebos, Dirk-Jan; Criner, Gerard J.; Shah, Pallav L.

    2017-01-01

    Interest in endoscopic lung volume reduction (ELVR) technologies for emphysema is consistently growing. In the last couple of months, several endoscopic options (e.g., endo-or intrabronchial valves, coil implants, and thermal vapor ablation) that have been evaluated in randomized controlled trials

  5. Minimally invasive non-surgical lung volume reduction

    International Nuclear Information System (INIS)

    Shen Liming; Zhou Dayong; Shen Junkang

    2006-01-01

    Minimally invasive treatment with lung volume reduction is the promising future for severe pulmonary emphysema patients. With emerging and improving of new techniques and instruments, it would become an important choice for managing severe emphysema. A comprehensive review is here documented through the correlative techniques, instruments, new achievements and latest research work. (authors)

  6. Time for the Global Rollout of Endoscopic Lung Volume Reduction

    NARCIS (Netherlands)

    Koegelenberg, Coenraad F. N.; Slebos, Dirk-Jan; Shah, Pallav L.; Theron, Johan; Dheda, Keertan; Allwood, Brian W.; Herth, Felix J. F.

    2015-01-01

    Chronic obstructive pulmonary disease remains one of the most common causes of morbidity and mortality globally. The disease is generally managed with pharmacotherapy, as well as guidance about smoking cessation and pulmonary rehabilitation. Endoscopic lung volume reduction (ELVR) has been proposed

  7. Development of Automatic Visceral Fat Volume Calculation Software for CT Volume Data

    Directory of Open Access Journals (Sweden)

    Mitsutaka Nemoto

    2014-01-01

    Full Text Available Objective. To develop automatic visceral fat volume calculation software for computed tomography (CT volume data and to evaluate its feasibility. Methods. A total of 24 sets of whole-body CT volume data and anthropometric measurements were obtained, with three sets for each of four BMI categories (under 20, 20 to 25, 25 to 30, and over 30 in both sexes. True visceral fat volumes were defined on the basis of manual segmentation of the whole-body CT volume data by an experienced radiologist. Software to automatically calculate visceral fat volumes was developed using a region segmentation technique based on morphological analysis with CT value threshold. Automatically calculated visceral fat volumes were evaluated in terms of the correlation coefficient with the true volumes and the error relative to the true volume. Results. Automatic visceral fat volume calculation results of all 24 data sets were obtained successfully and the average calculation time was 252.7 seconds/case. The correlation coefficients between the true visceral fat volume and the automatically calculated visceral fat volume were over 0.999. Conclusions. The newly developed software is feasible for calculating visceral fat volumes in a reasonable time and was proved to have high accuracy.

  8. Respiratory muscle activity related to flow and lung volume in preterm infants compared with term infants

    NARCIS (Netherlands)

    Hutten, Gerard J.; van Eykern, Leo A.; Latzin, Philipp; Thamrin, Cindy; van Aalderen, Wim M.; Frey, Urs

    2010-01-01

    Infants with chronic lung disease (CLD) have a capacity to maintain functional lung volume despite alterations to their lung mechanics. We hypothesize that they achieve this by altering breathing patterns and dynamic elevation of lung volume, leading to differences in the relationship between

  9. Endobronchial Valves for Endoscopic Lung Volume Reduction : Best Practice Recommendations from Expert Panel on Endoscopic Lung Volume Reduction

    NARCIS (Netherlands)

    Slebos, Dirk-Jan; Shah, Pallav L.; Herth, Felix J. F.; Valipour, Arschang

    Endoscopic lung volume reduction (ELVR) is being adopted as a treatment option for carefully selected patients suffering from severe emphysema. ELVR with the one-way endobronchial Zephyr valves (EBV) has been demonstrated to improve pulmonary function, exercise capacity, and quality of life in

  10. WE-G-BRD-07: Investigation of Distal Lung Atelectasis Following Stereotactic Body Radiation Therapy Using Regional Lung Volume Changes Between Pre- and Post- Treatment CT Scans

    Energy Technology Data Exchange (ETDEWEB)

    Diot, Q; Kavanagh, B; Miften, M [University of Colorado School of Medicine, Aurora, CO (United States)

    2014-06-15

    Purpose: To propose a quantitative method using lung deformations to differentiate between radiation-induced fibrosis and potential airway stenosis with distal atelectasis in patients treated with stereotactic body radiation therapy (SBRT) for lung tumors. Methods: Twenty-four lung patients with large radiation-induced density increases outside the high dose region had their pre- and post-treatment CT scans manually registered. They received SBRT treatments at our institution between 2002 and 2009 in 3 or 5 fractions, to a median total dose of 54Gy (range, 30–60). At least 50 anatomical landmarks inside the lung (airway branches) were paired for the pre- and post-treatment scans to guide the deformable registration of the lung structure, which was then interpolated to the whole lung using splines. Local volume changes between the planning and follow-up scans were calculated using the deformation field Jacobian. Hyperdense regions were classified as atelectatic or fibrotic based on correlations between regional density increases and significant volume contractions compared to the surrounding tissues. Results: Out of 24 patients, only 7 demonstrated a volume contraction that was at least one σ larger than the remaining lung average. Because they did not receive high doses, these shrunk hyperdense regions were likely showing distal atelectasis resulting from radiation-induced airway stenosis rather than conventional fibrosis. On average, the hyperdense regions extended 9.2 cm farther than the GTV contours but not significantly more than 8.6 cm for the other patients (p>0.05), indicating that a large offset between the radiation and hyperdense region centers is not a good surrogate for atelectasis. Conclusion: A method based on the relative comparison of volume changes between different dates was developed to identify potential lung regions experiencing distal atelectasis. Such a tool is essential to study which lung structures need to be avoided to prevent

  11. Pneumothorax as a complication of lung volume recruitment

    Directory of Open Access Journals (Sweden)

    Erik J.A. Westermann

    2013-06-01

    Full Text Available Lung volume recruitment involves deep inflation techniques to achieve maximum insufflation capacity in patients with respiratory muscle weakness, in order to increase peak cough flow, thus helping to maintain airway patency and improve ventilation. One of these techniques is air stacking, in which a manual resuscitator is used in order to inflate the lungs. Although intrathoracic pressures can rise considerably, there have been no reports of respiratory complications due to air stacking. However, reaching maximum insufflation capacity is not recommended in patients with known structural abnormalities of the lungs or chronic obstructive airway disease. We report the case of a 72-year-old woman who had poliomyelitis as a child, developed torsion scoliosis and post-polio syndrome, and had periodic but infrequent asthma attacks. After performing air stacking for 3 years, the patient suddenly developed a pneumothorax, indicating that this technique should be used with caution or not at all in patients with a known pulmonary pathology

  12. Monte Carlo dose calculations for BNCT treatment of diffuse human lung tumours

    International Nuclear Information System (INIS)

    Altieri, S.; Bortolussi, S.; Bruschi, P.

    2006-01-01

    In order to test the possibility to apply BNCT in the core of diffuse lung tumours, dose distribution calculations were made. The simulations were performed with the Monte Carlo code MCNP.4c2, using the male computational phantom Adam, version 07/94. Volumes of interest were voxelized for the tally requests, and results were obtained for tissues with and without Boron. Different collimated neutron sources were tested in order to establish the proper energies, as well as single and multiple beams to maximize neutron flux uniformity inside the target organs. Flux and dose distributions are reported. The use of two opposite epithermal neutron collimated beams insures good levels of dose homogeneity inside the lungs, with a substantially lower radiation dose delivered to surrounding structures. (author)

  13. Predictive equations for lung volumes from computed tomography for size matching in pulmonary transplantation.

    Science.gov (United States)

    Konheim, Jeremy A; Kon, Zachary N; Pasrija, Chetan; Luo, Qingyang; Sanchez, Pablo G; Garcia, Jose P; Griffith, Bartley P; Jeudy, Jean

    2016-04-01

    Size matching for lung transplantation is widely accomplished using height comparisons between donors and recipients. This gross approximation allows for wide variation in lung size and, potentially, size mismatch. Three-dimensional computed tomography (3D-CT) volumetry comparisons could offer more accurate size matching. Although recipient CT scans are universally available, donor CT scans are rarely performed. Therefore, predicted donor lung volumes could be used for comparison to measured recipient lung volumes, but no such predictive equations exist. We aimed to use 3D-CT volumetry measurements from a normal patient population to generate equations for predicted total lung volume (pTLV), predicted right lung volume (pRLV), and predicted left lung volume (pLLV), for size-matching purposes. Chest CT scans of 400 normal patients were retrospectively evaluated. 3D-CT volumetry was performed to measure total lung volume, right lung volume, and left lung volume of each patient, and predictive equations were generated. The fitted model was tested in a separate group of 100 patients. The model was externally validated by comparison of total lung volume with total lung capacity from pulmonary function tests in a subset of those patients. Age, gender, height, and race were independent predictors of lung volume. In the test group, there were strong linear correlations between predicted and actual lung volumes measured by 3D-CT volumetry for pTLV (r = 0.72), pRLV (r = 0.72), and pLLV (r = 0.69). A strong linear correlation was also observed when comparing pTLV and total lung capacity (r = 0.82). We successfully created a predictive model for pTLV, pRLV, and pLLV. These may serve as reference standards and predict donor lung volume for size matching in lung transplantation. Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  14. A Lagrangian Approach for Calculating Microsphere Deposition in a One-Dimensional Lung-Airway Model.

    Science.gov (United States)

    Vaish, Mayank; Kleinstreuer, Clement

    2015-09-01

    Using the open-source software openfoam as the solver, a novel approach to calculate microsphere transport and deposition in a 1D human lung-equivalent trumpet model (TM) is presented. Specifically, for particle deposition in a nonlinear trumpetlike configuration a new radial force has been developed which, along with the regular drag force, generates particle trajectories toward the wall. The new semi-empirical force is a function of any given inlet volumetric flow rate, micron-particle diameter, and lung volume. Particle-deposition fractions (DFs) in the size range from 2 μm to 10 μm are in agreement with experimental datasets for different laminar and turbulent inhalation flow rates as well as total volumes. Typical run times on a single processor workstation to obtain actual total deposition results at comparable accuracy are 200 times less than that for an idealized whole-lung geometry (i.e., a 3D-1D model with airways up to 23rd generation in single-path only).

  15. Low cost biological lung volume reduction therapy for advanced emphysema

    Directory of Open Access Journals (Sweden)

    Bakeer M

    2016-08-01

    Full Text Available Mostafa Bakeer,1 Taha Taha Abdelgawad,1 Raed El-Metwaly,1 Ahmed El-Morsi,1 Mohammad Khairy El-Badrawy,1 Solafa El-Sharawy2 1Chest Medicine Department, 2Clinical Pathology Department, Faculty of Medicine, Mansoura University, Mansoura, Egypt Background: Bronchoscopic lung volume reduction (BLVR, using biological agents, is one of the new alternatives to lung volume reduction surgery.Objectives: To evaluate efficacy and safety of biological BLVR using low cost agents including autologous blood and fibrin glue.Methods: Enrolled patients were divided into two groups: group A (seven patients in which autologous blood was used and group B (eight patients in which fibrin glue was used. The agents were injected through a triple lumen balloon catheter via fiberoptic bronchoscope. Changes in high resolution computerized tomography (HRCT volumetry, pulmonary function tests, symptoms, and exercise capacity were evaluated at 12 weeks postprocedure as well as for complications.Results: In group A, at 12 weeks postprocedure, there was significant improvement in the mean value of HRCT volumetry and residual volume/total lung capacity (% predicted (P-value: <0.001 and 0.038, respectively. In group B, there was significant improvement in the mean value of HRCT volumetry and (residual volume/total lung capacity % predicted (P-value: 0.005 and 0.004, respectively. All patients tolerated the procedure with no mortality.Conclusion: BLVR using autologous blood and locally prepared fibrin glue is a promising method for therapy of advanced emphysema in term of efficacy, safety as well as cost effectiveness. Keywords: BLVR, bronchoscopy, COPD, interventional pulmonology

  16. Lung volumes during sustained microgravity on Spacelab SLS-1

    Science.gov (United States)

    Elliott, Ann R.; Prisk, G. Kim; Guy, Harold J. B.; West, John B.

    1994-01-01

    Gravity is known to influence the mechanical behavior of the lung and chest wall. However, the effect of sustained microgravity (microgravity) on lung volumes has not been reported. Pulmonary function tests were performed by four subjects before, during, and after 9 days of microgravity exposure. Ground measurements were made in standing and supine postures. Tests were performed using a bag-in-box-and-flowmeter system and a respiratory mass spectrometer. Measurements included functional residual capacity (FRC), expiratory reserve volume (ERV), residual volume (RV), inspiratory and expiratory vital capacities (IVC and EVC), and tidal volume (V9sub T)). Total lung capacity (TLC) was derived from the measured EVC and RV values. With preflight standing values as a comparison, FRC was significantly reduced by 15% (approximately 500 ml) in microgravity and 32% in the supine posture. ERV was reduced by 10 - 20% in microgravity and decreased by 64% in the supine posture. RV was significantly reduced by 18% (310 ml) in microgravity but did not significantly change in the supine posture compared with standing. IVC and EVC were slightly reduced during the first 24 h of microgravity but returned to 1-G standing values within 72 h of microgravity exposure. IVC and EVC in the supine posture were significantly reduced by 12% compared with standing. During microgravity, V(sub T) decreased by 15% (approximately 90 ml), but supine V(sub T) was unchanged compared with preflight standing values. TLC decreased by approximately 8% during microgravity and in the supine posture compared with preflight standing. The reductions in FRC, ERV, and RV during microgravity are probably due to the cranial shift of the diaphragm, an increase in intrathoracic blood volume, and more uniform alveolar expansion.

  17. SU-F-T-600: Influence of Acuros XB and AAA Dose Calculation Algorithms On Plan Quality Metrics and Normal Lung Doses in Lung SBRT

    International Nuclear Information System (INIS)

    Yaparpalvi, R; Mynampati, D; Kuo, H; Garg, M; Tome, W; Kalnicki, S

    2016-01-01

    Purpose: To study the influence of superposition-beam model (AAA) and determinant-photon transport-solver (Acuros XB) dose calculation algorithms on the treatment plan quality metrics and on normal lung dose in Lung SBRT. Methods: Treatment plans of 10 Lung SBRT patients were randomly selected. Patients were prescribed to a total dose of 50-54Gy in 3–5 fractions (10?5 or 18?3). Doses were optimized accomplished with 6-MV using 2-arcs (VMAT). Doses were calculated using AAA algorithm with heterogeneity correction. For each plan, plan quality metrics in the categories- coverage, homogeneity, conformity and gradient were quantified. Repeat dosimetry for these AAA treatment plans was performed using AXB algorithm with heterogeneity correction for same beam and MU parameters. Plan quality metrics were again evaluated and compared with AAA plan metrics. For normal lung dose, V_2_0 and V_5 to (Total lung- GTV) were evaluated. Results: The results are summarized in Supplemental Table 1. PTV volume was mean 11.4 (±3.3) cm"3. Comparing RTOG 0813 protocol criteria for conformality, AXB plans yielded on average, similar PITV ratio (individual PITV ratio differences varied from −9 to +15%), reduced target coverage (−1.6%) and increased R50% (+2.6%). Comparing normal lung doses, the lung V_2_0 (+3.1%) and V_5 (+1.5%) were slightly higher for AXB plans compared to AAA plans. High-dose spillage ((V105%PD - PTV)/ PTV) was slightly lower for AXB plans but the % low dose spillage (D2cm) was similar between the two calculation algorithms. Conclusion: AAA algorithm overestimates lung target dose. Routinely adapting to AXB for dose calculations in Lung SBRT planning may improve dose calculation accuracy, as AXB based calculations have been shown to be closer to Monte Carlo based dose predictions in accuracy and with relatively faster computational time. For clinical practice, revisiting dose-fractionation in Lung SBRT to correct for dose overestimates attributable to algorithm

  18. SU-F-T-600: Influence of Acuros XB and AAA Dose Calculation Algorithms On Plan Quality Metrics and Normal Lung Doses in Lung SBRT

    Energy Technology Data Exchange (ETDEWEB)

    Yaparpalvi, R; Mynampati, D; Kuo, H; Garg, M; Tome, W; Kalnicki, S [Montefiore Medical Center, Bronx, NY (United States)

    2016-06-15

    Purpose: To study the influence of superposition-beam model (AAA) and determinant-photon transport-solver (Acuros XB) dose calculation algorithms on the treatment plan quality metrics and on normal lung dose in Lung SBRT. Methods: Treatment plans of 10 Lung SBRT patients were randomly selected. Patients were prescribed to a total dose of 50-54Gy in 3–5 fractions (10?5 or 18?3). Doses were optimized accomplished with 6-MV using 2-arcs (VMAT). Doses were calculated using AAA algorithm with heterogeneity correction. For each plan, plan quality metrics in the categories- coverage, homogeneity, conformity and gradient were quantified. Repeat dosimetry for these AAA treatment plans was performed using AXB algorithm with heterogeneity correction for same beam and MU parameters. Plan quality metrics were again evaluated and compared with AAA plan metrics. For normal lung dose, V{sub 20} and V{sub 5} to (Total lung- GTV) were evaluated. Results: The results are summarized in Supplemental Table 1. PTV volume was mean 11.4 (±3.3) cm{sup 3}. Comparing RTOG 0813 protocol criteria for conformality, AXB plans yielded on average, similar PITV ratio (individual PITV ratio differences varied from −9 to +15%), reduced target coverage (−1.6%) and increased R50% (+2.6%). Comparing normal lung doses, the lung V{sub 20} (+3.1%) and V{sub 5} (+1.5%) were slightly higher for AXB plans compared to AAA plans. High-dose spillage ((V105%PD - PTV)/ PTV) was slightly lower for AXB plans but the % low dose spillage (D2cm) was similar between the two calculation algorithms. Conclusion: AAA algorithm overestimates lung target dose. Routinely adapting to AXB for dose calculations in Lung SBRT planning may improve dose calculation accuracy, as AXB based calculations have been shown to be closer to Monte Carlo based dose predictions in accuracy and with relatively faster computational time. For clinical practice, revisiting dose-fractionation in Lung SBRT to correct for dose overestimates

  19. Effect of Inhomogeneity correction for lung volume model in TPS

    International Nuclear Information System (INIS)

    Chung, Se Young; Lee, Sang Rok; Kim, Young Bum; Kwon, Young Ho

    2004-01-01

    The phantom that includes high density materials such as steel was custom-made to fix lung and bone in order to evaluation inhomogeneity correction at the time of conducting radiation therapy to treat lung cancer. Using this, values resulting from the inhomogeneous correction algorithm are compared on the 2 and 3 dimensional radiation therapy planning systems. Moreover, change in dose calculation was evaluated according to inhomogeneous by comparing with the actual measurement. As for the image acquisition, inhomogeneous correction phantom(Pig's vertebra, steel(8.21 g/cm 3 ), cork(0.23 g/cm 3 )) that was custom-made and the CT(Volume zoom, Siemens, Germany) were used. As for the radiation therapy planning system, Marks Plan(2D) and XiO(CMS, USA, 3D) were used. To compare with the measurement value, linear accelerator(CL/1800, Varian, USA) and ion chamber were used. Image, obtained from the CT was used to obtain point dose and dose distribution from the region of interest (ROI) while on the radiation therapy planning device. After measurement was conducted under the same conditions, value on the treatment planning device and measured value were subjected to comparison and analysis. And difference between the resulting for the evaluation on the use (or non-use) of inhomogeneity correction algorithm, and diverse inhomogeneity correction algorithm that is included in the radiation therapy planning device was compared as well. As result of comparing the results of measurement value on the region of interest within the inhomogeneity correction phantom and the value that resulted from the homogeneous and inhomogeneous correction, gained from the therapy planning device, margin of error of the measurement value and inhomogeneous correction value at the location 1 of the lung showed 0.8% on 2D and 0.5% on 3D. Margin of error of the measurement value and inhomogeneous correction value at the location 1 of the steel showed 12% on 2D and 5% on 3D, however, it is possible to

  20. Automatic delineation of functional lung volumes with 68Ga-ventilation/perfusion PET/CT.

    Science.gov (United States)

    Le Roux, Pierre-Yves; Siva, Shankar; Callahan, Jason; Claudic, Yannis; Bourhis, David; Steinfort, Daniel P; Hicks, Rodney J; Hofman, Michael S

    2017-10-10

    Functional volumes computed from 68 Ga-ventilation/perfusion (V/Q) PET/CT, which we have shown to correlate with pulmonary function test parameters (PFTs), have potential diagnostic utility in a variety of clinical applications, including radiotherapy planning. An automatic segmentation method would facilitate delineation of such volumes. The aim of this study was to develop an automated threshold-based approach to delineate functional volumes that best correlates with manual delineation. Thirty lung cancer patients undergoing both V/Q PET/CT and PFTs were analyzed. Images were acquired following inhalation of Galligas and, subsequently, intravenous administration of 68 Ga-macroaggreted-albumin (MAA). Using visually defined manual contours as the reference standard, various cutoff values, expressed as a percentage of the maximal pixel value, were applied. The average volume difference and Dice similarity coefficient (DSC) were calculated, measuring the similarity of the automatic segmentation and the reference standard. Pearson's correlation was also calculated to compare automated volumes with manual volumes, and automated volumes optimized to PFT indices. For ventilation volumes, mean volume difference was lowest (- 0.4%) using a 15%max threshold with Pearson's coefficient of 0.71. Applying this cutoff, median DSC was 0.93 (0.87-0.95). Nevertheless, limits of agreement in volume differences were large (- 31.0 and 30.2%) with differences ranging from - 40.4 to + 33.0%. For perfusion volumes, mean volume difference was lowest and Pearson's coefficient was highest using a 15%max threshold (3.3% and 0.81, respectively). Applying this cutoff, median DSC was 0.93 (0.88-0.93). Nevertheless, limits of agreement were again large (- 21.1 and 27.8%) with volume differences ranging from - 18.6 to + 35.5%. Using the 15%max threshold, moderate correlation was demonstrated with FEV1/FVC (r = 0.48 and r = 0.46 for ventilation and perfusion images, respectively

  1. Dosimetric impact of Acuros XB deterministic radiation transport algorithm for heterogeneous dose calculation in lung cancer

    International Nuclear Information System (INIS)

    Han Tao; Followill, David; Repchak, Roman; Molineu, Andrea; Howell, Rebecca; Salehpour, Mohammad; Mikell, Justin; Mourtada, Firas

    2013-01-01

    Purpose: The novel deterministic radiation transport algorithm, Acuros XB (AXB), has shown great potential for accurate heterogeneous dose calculation. However, the clinical impact between AXB and other currently used algorithms still needs to be elucidated for translation between these algorithms. The purpose of this study was to investigate the impact of AXB for heterogeneous dose calculation in lung cancer for intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT). Methods: The thorax phantom from the Radiological Physics Center (RPC) was used for this study. IMRT and VMAT plans were created for the phantom in the Eclipse 11.0 treatment planning system. Each plan was delivered to the phantom three times using a Varian Clinac iX linear accelerator to ensure reproducibility. Thermoluminescent dosimeters (TLDs) and Gafchromic EBT2 film were placed inside the phantom to measure delivered doses. The measurements were compared with dose calculations from AXB 11.0.21 and the anisotropic analytical algorithm (AAA) 11.0.21. Two dose reporting modes of AXB, dose-to-medium in medium (D m,m ) and dose-to-water in medium (D w,m ), were studied. Point doses, dose profiles, and gamma analysis were used to quantify the agreement between measurements and calculations from both AXB and AAA. The computation times for AAA and AXB were also evaluated. Results: For the RPC lung phantom, AAA and AXB dose predictions were found in good agreement to TLD and film measurements for both IMRT and VMAT plans. TLD dose predictions were within 0.4%–4.4% to AXB doses (both D m,m and D w,m ); and within 2.5%–6.4% to AAA doses, respectively. For the film comparisons, the gamma indexes (±3%/3 mm criteria) were 94%, 97%, and 98% for AAA, AXB Dm,m , and AXB Dw,m , respectively. The differences between AXB and AAA in dose–volume histogram mean doses were within 2% in the planning target volume, lung, heart, and within 5% in the spinal cord. However

  2. A study of different dose calculation methods and the impact on the dose evaluation protocol in lung stereotactic radiation therapy

    International Nuclear Information System (INIS)

    Takada, Takahiro; Furuya, Tomohisa; Ozawa, Shuichi; Ito, Kana; Kurokawa, Chie; Karasawa, Kumiko; Miura, Kohei

    2008-01-01

    AAA (analytical anisotropic algorithm) dose calculation, which shows a better performance for heterogeneity correction, was tested for lung stereotactic radiation therapy (SBRT) in comparison to conventional PBC (pencil beam convolution method) to evaluate its impact on tumor dose parameters. Eleven lung SBRT patients who were treated with photon 4 MV beams in our department between April 2003 and February 2007 were reviewed. Clinical target volume (CTV) was delineated including the spicula region on planning CT images. Planning target volume (PTV) was defined by adding the internal target volume (ITV) and set-up margin (SM) of 5 mm from CTV, and then an multileaf collimator (MLC) penumbra margin of another 5 mm was also added. Six-port non-coplanar beams were employed, and a total prescribed dose of 48 Gy was defined at the isocenter point with four fractions. The entire treatment for an individual patient was completed within 8 days. Under the same prescribed dose, calculated dose distribution, dose volume histogram (DVH), and tumor dose parameters were compared between two dose calculation methods. In addition, the fractionated prescription dose was repeatedly scaled until the monitor units (MUs) calculated by AAA reached a level of MUs nearly identical to those achieved by PBC. AAA resulted in significantly less D95 (irradiation dose that included 95% volume of PTV) and minimal dose in PTV compared to PBC. After rescaling of each MU for each beam in the AAA plan, there was no revision of the isocenter of the prescribed dose required. However, when the PTV volume was less than 20 cc, a 4% lower prescription resulted in nearly identical MUs between AAA and PBC. The prescribed dose in AAA should be the same as that in PBC, if the dose is administered at the isocenter point. However, planners should compare DVHs and dose distributions between AAA and PBC for a small lung tumor with a PTV volume less than approximately 20 cc. (author)

  3. [Lung volume reduction surgery for emphysema and bullous pulmonary emphysema].

    Science.gov (United States)

    Le Pimpec-Barthes, F; Das Neves-Pereira, J-C; Cazes, A; Arame, A; Grima, R; Hubsch, J-P; Zukerman, C; Hernigou, A; Badia, A; Bagan, P; Delclaux, C; Dusser, D; Riquet, M

    2012-04-01

    The improvement of respiratory symptoms for emphysematous patients by surgery is a concept that has evolved over time. Initially used for giant bullae, this surgery was then applied to patients with diffuse microbullous emphysema. The physiological and pathological concepts underlying these surgical procedures are the same in both cases: improve respiratory performance by reducing the high intrapleural pressure. The functional benefit of lung volume reduction surgery (LVRS) in the severe diffuse emphysema has been validated by the National Emphysema Treatment Trial (NETT) and the later studies which allowed to identify prognostic factors. The quality of the clinical, morphological and functional data made it possible to develop recommendations now widely used in current practice. Surgery for giant bullae occurring on little or moderately emphysematous lung is often a simpler approach but also requires specialised support to optimize its results. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  4. Robust volume calculations for Constructive Solid Geometry (CSG) components in Monte Carlo transport calculations

    Energy Technology Data Exchange (ETDEWEB)

    Millman, D. L. [Dept. of Computer Science, Univ. of North Carolina at Chapel Hill (United States); Griesheimer, D. P.; Nease, B. R. [Bechtel Marine Propulsion Corporation, Bertis Atomic Power Laboratory (United States); Snoeyink, J. [Dept. of Computer Science, Univ. of North Carolina at Chapel Hill (United States)

    2012-07-01

    In this paper we consider a new generalized algorithm for the efficient calculation of component object volumes given their equivalent constructive solid geometry (CSG) definition. The new method relies on domain decomposition to recursively subdivide the original component into smaller pieces with volumes that can be computed analytically or stochastically, if needed. Unlike simpler brute-force approaches, the proposed decomposition scheme is guaranteed to be robust and accurate to within a user-defined tolerance. The new algorithm is also fully general and can handle any valid CSG component definition, without the need for additional input from the user. The new technique has been specifically optimized to calculate volumes of component definitions commonly found in models used for Monte Carlo particle transport simulations for criticality safety and reactor analysis applications. However, the algorithm can be easily extended to any application which uses CSG representations for component objects. The paper provides a complete description of the novel volume calculation algorithm, along with a discussion of the conjectured error bounds on volumes calculated within the method. In addition, numerical results comparing the new algorithm with a standard stochastic volume calculation algorithm are presented for a series of problems spanning a range of representative component sizes and complexities. (authors)

  5. Robust volume calculations for Constructive Solid Geometry (CSG) components in Monte Carlo transport calculations

    International Nuclear Information System (INIS)

    Millman, D. L.; Griesheimer, D. P.; Nease, B. R.; Snoeyink, J.

    2012-01-01

    In this paper we consider a new generalized algorithm for the efficient calculation of component object volumes given their equivalent constructive solid geometry (CSG) definition. The new method relies on domain decomposition to recursively subdivide the original component into smaller pieces with volumes that can be computed analytically or stochastically, if needed. Unlike simpler brute-force approaches, the proposed decomposition scheme is guaranteed to be robust and accurate to within a user-defined tolerance. The new algorithm is also fully general and can handle any valid CSG component definition, without the need for additional input from the user. The new technique has been specifically optimized to calculate volumes of component definitions commonly found in models used for Monte Carlo particle transport simulations for criticality safety and reactor analysis applications. However, the algorithm can be easily extended to any application which uses CSG representations for component objects. The paper provides a complete description of the novel volume calculation algorithm, along with a discussion of the conjectured error bounds on volumes calculated within the method. In addition, numerical results comparing the new algorithm with a standard stochastic volume calculation algorithm are presented for a series of problems spanning a range of representative component sizes and complexities. (authors)

  6. Effect of contrast on treatment planning system dose calculations in the lung

    International Nuclear Information System (INIS)

    Lees, J.; Holloway, L.; Fuller, M.; Forstner, D.

    2004-01-01

    Full text: Contrast-enhanced x-ray computed tomography is utilised in the planning of radiotherapy lung treatments to allow greater accuracy in defining tumour volume and nodal areas. The use of contrast results in increased density in the region of the tumour and may result in an overall increased density in the lung volume. It is possible that this change in density may affect the accuracy of any dose calculations based on this CT data. As yet, the effect of the contrast agent on the calculations performed by the treatment planning computer is unclear. Ideally, a study would be undertaken using pre- and post- contrast patient data, however this may be considered unethical as an extra CT scan would be required. For this reason, the following study was undertaken to assess the possible impact in a simulated environment. The object of this study was to explore the effect of the contrast agent upon the isodose curves and the monitor units calculated by the treatment planning system. Two investigations were made. Initially, pre- and post-contrast images were acquired using an anthropomorphic phantom. Contrast-enhancement was simulated by replacing cylindrical sections of the lung with lengths of drinking straw containing contrast agent. The effect of increased density in the tumour volume was considered in this comparison. Secondly, block density corrections were used in an existing patient dataset to simulate an increase in lung density and compared with the original dataset. In the two investigations, a treatment was generated using both datasets. Fields were placed on the non contrast-enhanced scan, and then transferred onto the contrast-enhanced scan. The numbers of monitor units calculated in each of the plans were compared, as were the resulting isodose curves. In the first investigation, the relative electron density in the contrast-enhanced scan varied between 0.523 and 1.705 within the tumour volume. This resulted from the presence of undiluted contrast agent

  7. Volume calculation from limited number of MR imaging sections

    International Nuclear Information System (INIS)

    Wang, J.; Mezrich, R.; Sebok, D.

    1988-01-01

    Magnetic resonance imaging is an accurate and noninvasive way to obtain cardiac geometrical information. For the quantification of left ventricular dynamic parameters, sections are taken along the long axis of the ventricle. Due to the limited number of sections that can be obtained in a reasonable amount of scanning time, the estimation of longitudinal dimension is usually the cause of error in volume calculation. The starting and ending sections are best estimated by guidance of the short axis cuts. This can only guarantee first-order accuracy. Simpson's rule for summation of areas to calculate volume, which is the commonly used method, assumes an accurate knowledge of the starting and ending points of integration. When this assumption is not perfectly met, Simpson's rule tends to unsystemically over- or underestimate the true volume. Due to this concern, some researchers adopt the images from the short axis cut to aid the volume calculation. This can improve the accuracy, but makes the already long scanning time longer. The authors have derived a method of extrapolation and intrapolation based on no more information than usually available to correct the volume over- or underestimated by the Simpson's rule

  8. New approach to lung cancer screening with helical volume CT

    International Nuclear Information System (INIS)

    Midorikawa, S.; Hashimoto, N.; Katakura, T.; Suzuki, K.

    1990-01-01

    This paper evaluates the relationship between reducing radiation dose to the patient and maintaining the clinical quality of the chest image in lung cancer screening by helical-volume CT (HVCT). The authors evaluated the changing relationship between radiation dose and clinical quality after changing the HVCY scanning conditions (such as stroke of patient transport and section thickness) as well as adding copper filters of various thickness and using high-voltage x-ray examination to complement CT examinations. The authors were able to reduce radiation dose by changing the HVCT scanning conditions (eg, stroke of 20 mm/sec, with a section thickness of 10 mm)

  9. Lung volumes during sustained microgravity on Spacelab SLS-1

    Science.gov (United States)

    Elliott, Ann R.; Prisk, Gordon Kim; Guy, Harold J. B.; West, John B.

    1994-01-01

    Gravity is known to influence the topographical gradients of pulmonary ventilation, perfusion, and pleural pressures. The effect of sustained microgravity on lung volumes has not previously been investigated. Pulmonary function tests were performed by four subjects before, during, and after 9 days of microgravity exposure. Ground measurements were made in standing and supine postures. Tests were performed using a bag-in-box and flowmeter system and a respiratory mass spectrometer. Measurements of tidal volume (V(sub T)), expiratory reserve volume (ERV), inspiratory and expiratory vital capacities (IVC, EVC), functional residual capacity (FRC), and residual volume (RV) were made. During microgravity, V(sub T) decreased by 15%. IVC and EVC were slightly reduced during the first 24 hrs of microgravity and returned to 1 g standing values within 72 hrs after the onset of microgravity. FRC was reduced by 15% and ERV decreased by 10-20%. RV was significantly reduced by 18%. The reductions in FRC, ERV, and V(sub T) during microgravity are probably due to the cranial shift of the diaphragm and an increase in intrathoracic blood volume.

  10. Programmable calculator programs to solve softwood volume and value equations.

    Science.gov (United States)

    Janet K. Ayer. Sachet

    1982-01-01

    This paper presents product value and product volume equations as programs for handheld calculators. These tree equations are for inland Douglas-fir, young-growth Douglas-fir, western white pine, ponderosa pine, and western larch. Operating instructions and an example are included.

  11. Lung deposition of sub-micron aerosols calculated as a function of age and breathing rate

    International Nuclear Information System (INIS)

    James, A.C.

    1978-01-01

    Experimental measurements of lung deposition and especially of regional deposition, of aerosols in the sub-micron size range have been so few that it is worthwhile establishing a method of calculation. A computer routine has therefore been developed to calculate aerosol deposition in successive bronchial and bronchiolar generations of the Weibel 'A' model of human lung for the sub-micron size range where deposition occurs solely by diffusion. This model can be scaled to represent lungs at various ages and vital capacities. Some calculated results are presented here and compared with measurements of lung deposition made under carefully controlled conditions in humans. (author)

  12. [Interpretation and use of routine pulmonary function tests: Spirometry, static lung volumes, lung diffusion, arterial blood gas, methacholine challenge test and 6-minute walk test].

    Science.gov (United States)

    Bokov, P; Delclaux, C

    2016-02-01

    Resting pulmonary function tests (PFT) include the assessment of ventilatory capacity: spirometry (forced expiratory flows and mobilisable volumes) and static volume assessment, notably using body plethysmography. Spirometry allows the potential definition of obstructive defect, while static volume assessment allows the potential definition of restrictive defect (decrease in total lung capacity) and thoracic hyperinflation (increase in static volumes). It must be kept in mind that this evaluation is incomplete and that an assessment of ventilatory demand is often warranted, especially when facing dyspnoea: evaluation of arterial blood gas (searching for respiratory insufficiency) and measurement of the transfer coefficient of the lung, allowing with the measurement of alveolar volume to calculate the diffusing capacity of the lung for CO (DLCO: assessment of alveolar-capillary wall and capillary blood volume). All these pulmonary function tests have been the subject of an Americano-European Task force (standardisation of lung function testing) published in 2005, and translated in French in 2007. Interpretative strategies for lung function tests have been recommended, which define abnormal lung function tests using the 5th and 95th percentiles of predicted values (lower and upper limits of normal values). Thus, these recommendations need to be implemented in all pulmonary function test units. A methacholine challenge test will only be performed in the presence of an intermediate pre-test probability for asthma (diagnostic uncertainty), which is an infrequent setting. The most convenient exertional test is the 6-minute walk test that allows the assessment of walking performance, the search for arterial desaturation and the quantification of dyspnoea complaint. Copyright © 2015 Société nationale française de médecine interne (SNFMI). Published by Elsevier SAS. All rights reserved.

  13. Paradigm shift in LUNG SBRT dose calculation associated with Heterogeneity correction

    International Nuclear Information System (INIS)

    Zucca Aparicio, D.; Perez Moreno, J. M.; Fernandez Leton, P.; Garcia Ruiz-Zorrilla, J.; Pinto Monedero, M.; Marti Asensjo, J.; Alonso Iracheta, L.

    2015-01-01

    Treatment of lung injury SBRT requires great dosimetric accuracy, the increasing clinical importance of dose calculation heterogeneities introducing algorithms that adequately model the transport of particles narrow beams in media of low density, as with Monte Carlo calculation. (Author)

  14. Estimation of lung volume and pressure from electrocardiogram

    KAUST Repository

    Elsayed, Gamal Eldin Fathy Amin

    2011-05-01

    The Electrocardiography (ECG) is a tool measuring the electrical excitation of the heart that is extensively used for diagnosis and monitoring of heart diseases. The ECG signal reflects not only the heart activity but also many other physiological processes. The respiratory activity is a prominent process that affects the ECG signal due to the close proximity of the heart and the lungs and, on the other hand, due to neural regulatory processes. In this paper, several means for the estimation of the respiratory process from the ECG signal are presented. The results show a strong correlation of the voltage difference between the R and S peak of the ECG and the lung\\'s volume and pressure. Correlation was also found for some features of the vector ECG, which is a two dimensional graph of two different ECG signals. The potential benefit of the multiparametric evaluation of the ECG signal is a reduction of the number of sensors connected to patients, which will increase the patients\\' comfort and reduce the costs associated with healthcare. In particular, it is relevant for sleep monitoring, where a reduction of the number of different sensors would facilitate a more natural sleeping environment and hence a higher sensitivity of the diagnosis. © 2011 IEEE.

  15. GTV-based prescription in SBRT for lung lesions using advanced dose calculation algorithms

    International Nuclear Information System (INIS)

    Lacornerie, Thomas; Lisbona, Albert; Mirabel, Xavier; Lartigau, Eric; Reynaert, Nick

    2014-01-01

    The aim of current study was to investigate the way dose is prescribed to lung lesions during SBRT using advanced dose calculation algorithms that take into account electron transport (type B algorithms). As type A algorithms do not take into account secondary electron transport, they overestimate the dose to lung lesions. Type B algorithms are more accurate but still no consensus is reached regarding dose prescription. The positive clinical results obtained using type A algorithms should be used as a starting point. In current work a dose-calculation experiment is performed, presenting different prescription methods. Three cases with three different sizes of peripheral lung lesions were planned using three different treatment platforms. For each individual case 60 Gy to the PTV was prescribed using a type A algorithm and the dose distribution was recalculated using a type B algorithm in order to evaluate the impact of the secondary electron transport. Secondly, for each case a type B algorithm was used to prescribe 48 Gy to the PTV, and the resulting doses to the GTV were analyzed. Finally, prescriptions based on specific GTV dose volumes were evaluated. When using a type A algorithm to prescribe the same dose to the PTV, the differences regarding median GTV doses among platforms and cases were always less than 10% of the prescription dose. The prescription to the PTV based on type B algorithms, leads to a more important variability of the median GTV dose among cases and among platforms, (respectively 24%, and 28%). However, when 54 Gy was prescribed as median GTV dose, using a type B algorithm, the variability observed was minimal. Normalizing the prescription dose to the median GTV dose for lung lesions avoids variability among different cases and treatment platforms of SBRT when type B algorithms are used to calculate the dose. The combination of using a type A algorithm to optimize a homogeneous dose in the PTV and using a type B algorithm to prescribe the

  16. Cross-sectional changes in lung volume measured by electrical impedance tomography are representative for the whole lung in ventilated preterm infants

    NARCIS (Netherlands)

    van der Burg, Pauline S.; Miedema, Martijn; de Jongh, Frans H.; Frerichs, Inez; van Kaam, Anton H.

    2014-01-01

    Electrical impedance tomography measures lung volume in a cross-sectional slice of the lung. Whether these cross-sectional volume changes are representative of the whole lung has only been investigated in adults, showing conflicting results. This study aimed to compare cross-sectional and whole lung

  17. Risk factors for radiation pneumonitis after stereotactic radiation therapy for lung tumours: clinical usefulness of the planning target volume to total lung volume ratio.

    Science.gov (United States)

    Ueyama, Tomoko; Arimura, Takeshi; Takumi, Koji; Nakamura, Fumihiko; Higashi, Ryutaro; Ito, Soichiro; Fukukura, Yoshihiko; Umanodan, Tomokazu; Nakajo, Masanori; Koriyama, Chihaya; Yoshiura, Takashi

    2018-06-01

    To identify risk factors for symptomatic radiation pneumonitis (RP) after stereotactic radiation therapy (SRT) for lung tumours. We retrospectively evaluated 68 lung tumours in 63 patients treated with SRT between 2011 and 2015. RP was graded according to the National Cancer Institute-Common Terminology Criteria for Adverse Events version 4.0. SRT was delivered at 7.0-12.0 Gy per each fraction, once daily, to a total of 48-64 Gy (median, 50 Gy). Univariate analysis was performed to assess patient- and treatment-related factors, including age, sex, smoking index (SI), pulmonary function, tumour location, serum Krebs von den Lungen-6 value (KL-6), dose-volume metrics (V5, V10, V20, V30, V40 and VS5), homogeneity index of the planning target volume (PTV), PTV dose, mean lung dose (MLD), contralateral MLD and V2, PTV volume, lung volume and the PTV/lung volume ratio (PTV/Lung). Performance of PTV/Lung in predicting symptomatic RP was also analysed using receiver operating characteristic (ROC) analysis. The median follow-up period was 21 months. 10 of 63 patients (15.9%) developed symptomatic RP after SRT. On univariate analysis, V10, V20, PTV volume and PTV/Lung were significantly associated with occurrence of RP  ≥Grade 2. ROC curves indicated that symptomatic RP could be predicted using PTV/Lung [area under curve (AUC): 0.88, confidence interval (CI: 0.78-0.95), cut-off value: 1.09, sensitivity: 90.0% and specificity: 72.4%]. PTV/Lung is a good predictor of symptomatic RP after SRT. Advances in knowledge: The cases with high PTV/Lung should be carefully monitored with caution for the occurrence of RP after SRT.

  18. Metallic artifact mitigation and organ-constrained tissue assignment for Monte Carlo calculations of permanent implant lung brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, J. G. H.; Miksys, N.; Thomson, R. M., E-mail: rthomson@physics.carleton.ca [Carleton Laboratory for Radiotherapy Physics, Department of Physics, Carleton University, Ottawa, Ontario K1S 5B6 (Canada); Furutani, K. M. [Department of Radiation Oncology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905 (United States)

    2014-01-15

    Purpose: To investigate methods of generating accurate patient-specific computational phantoms for the Monte Carlo calculation of lung brachytherapy patient dose distributions. Methods: Four metallic artifact mitigation methods are applied to six lung brachytherapy patient computed tomography (CT) images: simple threshold replacement (STR) identifies high CT values in the vicinity of the seeds and replaces them with estimated true values; fan beam virtual sinogram replaces artifact-affected values in a virtual sinogram and performs a filtered back-projection to generate a corrected image; 3D median filter replaces voxel values that differ from the median value in a region of interest surrounding the voxel and then applies a second filter to reduce noise; and a combination of fan beam virtual sinogram and STR. Computational phantoms are generated from artifact-corrected and uncorrected images using several tissue assignment schemes: both lung-contour constrained and unconstrained global schemes are considered. Voxel mass densities are assigned based on voxel CT number or using the nominal tissue mass densities. Dose distributions are calculated using the EGSnrc user-code BrachyDose for{sup 125}I, {sup 103}Pd, and {sup 131}Cs seeds and are compared directly as well as through dose volume histograms and dose metrics for target volumes surrounding surgical sutures. Results: Metallic artifact mitigation techniques vary in ability to reduce artifacts while preserving tissue detail. Notably, images corrected with the fan beam virtual sinogram have reduced artifacts but residual artifacts near sources remain requiring additional use of STR; the 3D median filter removes artifacts but simultaneously removes detail in lung and bone. Doses vary considerably between computational phantoms with the largest differences arising from artifact-affected voxels assigned to bone in the vicinity of the seeds. Consequently, when metallic artifact reduction and constrained tissue

  19. Lobar analysis of collapsibility indices to assess functional lung volumes in COPD patients.

    Science.gov (United States)

    Kitano, Mariko; Iwano, Shingo; Hashimoto, Naozumi; Matsuo, Keiji; Hasegawa, Yoshinori; Naganawa, Shinji

    2014-01-01

    We investigated correlations between lung volume collapsibility indices and pulmonary function test (PFT) results and assessed lobar differences in chronic obstructive pulmonary disease (COPD) patients, using paired inspiratory and expiratory three dimensional (3D) computed tomography (CT) images. We retrospectively assessed 28 COPD patients who underwent paired inspiratory and expiratory CT and PFT exams on the same day. A computer-aided diagnostic system calculated total lobar volume and emphysematous lobar volume (ELV). Normal lobar volume (NLV) was determined by subtracting ELV from total lobar volume, both for inspiratory phase (NLVI) and for expiratory phase (NLVE). We also determined lobar collapsibility indices: NLV collapsibility ratio (NLVCR) (%)=(1-NLVE/NLVI)×100%. Associations between lobar volumes and PFT results, and collapsibility indices and PFT results were determined by Pearson correlation analysis. NLVCR values were significantly correlated with PFT results. Forced expiratory volume in 1 second, measured as percent of predicted results (FEV1%P) was significantly correlated with NLVCR values for the lower lobes (Pvolume, measured as percent of predicted (DLCO/VA%P) results were strongly correlated with ELVI for the upper lobes (Ppulmonary function in COPD patients.

  20. SU-G-BRC-08: Evaluation of Dose Mass Histogram as a More Representative Dose Description Method Than Dose Volume Histogram in Lung Cancer Patients

    Energy Technology Data Exchange (ETDEWEB)

    Liu, J; Eldib, A; Ma, C [Fox Chase Cancer Center, Philadelphia, PA (United States); Lin, M [The University of Texas Southwestern Medical Ctr, Dallas, TX (United States); Li, J [Cyber Medical Inc, Xian, Shaanxi (China); Mora, G [Universidade de Lisboa, Codex, Lisboa (Portugal)

    2016-06-15

    Purpose: Dose-volume-histogram (DVH) is widely used for plan evaluation in radiation treatment. The concept of dose-mass-histogram (DMH) is expected to provide a more representative description as it accounts for heterogeneity in tissue density. This study is intended to assess the difference between DVH and DMH for evaluating treatment planning quality. Methods: 12 lung cancer treatment plans were exported from the treatment planning system. DVHs for the planning target volume (PTV), the normal lung and other structures of interest were calculated. DMHs were calculated in a similar way as DVHs expect that the voxel density converted from the CT number was used in tallying the dose histogram bins. The equivalent uniform dose (EUD) was calculated based on voxel volume and mass, respectively. The normal tissue complication probability (NTCP) in relation to the EUD was calculated for the normal lung to provide quantitative comparison of DVHs and DMHs for evaluating the radiobiological effect. Results: Large differences were observed between DVHs and DMHs for lungs and PTVs. For PTVs with dense tumor cores, DMHs are higher than DVHs due to larger mass weighing in the high dose conformal core regions. For the normal lungs, DMHs can either be higher or lower than DVHs depending on the target location within the lung. When the target is close to the lower lung, DMHs show higher values than DVHs because the lower lung has higher density than the central portion or the upper lung. DMHs are lower than DVHs for targets in the upper lung. The calculated NTCPs showed a large range of difference between DVHs and DMHs. Conclusion: The heterogeneity of lung can be well considered using DMH for evaluating target coverage and normal lung pneumonitis. Further studies are warranted to quantify the benefits of DMH over DVH for plan quality evaluation.

  1. 105-KW Sandfilter Backwash Pit sludge volume calculation

    International Nuclear Information System (INIS)

    Dodd, E.N. Jr.

    1995-01-01

    The volume of sludge contained in the 100-KW Sandfilter Backwash Pit (SFBWP) was calculated from depth measurements of the sludge, pit dimension measurements and analysis of video tape recordings taken by an underwater camera. The term sludge as used in this report is any combination of sand, sediment, or corrosion products visible in the SFBWP area. This work was performed to determine baseline volume for use in determination of quantities of uranium and plutonium deposited in the pit from sandfilter backwashes. The SFBWP has three areas where sludge is deposited: (1) the main pit floor, (2) the transfer channel floor, and (3) the surfaces and structures in the SFBWP. The depths of sludge and the uniformity of deposition varies significantly between these three areas. As a result, each of the areas was evaluated separately. The total volume of sludge determined was 3.75 M 3 (132.2 ft 3 )

  2. Pulmonary vascular volume ratio measured by cardiac computed tomography in children and young adults with congenital heart disease: comparison with lung perfusion scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Goo, Hyun Woo; Park, Sang Hyub [University of Ulsan College of Medicine, Department of Radiology and Research Institute of Radiology, Asan Medical Center, Seoul (Korea, Republic of)

    2017-11-15

    Lung perfusion scintigraphy is regarded as the gold standard for evaluating differential lung perfusion ratio in congenital heart disease. To compare cardiac CT with lung perfusion scintigraphy for estimated pulmonary vascular volume ratio in patients with congenital heart disease. We included 52 children and young adults (median age 4 years, range 2 months to 28 years; 31 males) with congenital heart disease who underwent cardiac CT and lung perfusion scintigraphy without an interim surgical or transcatheter intervention and within 1 year. We calculated the right and left pulmonary vascular volumes using threshold-based CT volumetry. Then we compared right pulmonary vascular volume percentages at cardiac CT with right lung perfusion percentages at lung perfusion scintigraphy by using paired t-test and Bland-Altman analysis. The right pulmonary vascular volume percentages at cardiac CT (66.3 ± 14.0%) were significantly smaller than the right lung perfusion percentages at lung perfusion scintigraphy (69.1 ± 15.0%; P=0.001). Bland-Altman analysis showed a mean difference of -2.8 ± 5.8% and 95% limits of agreement (-14.1%, 8.5%) between these two variables. Cardiac CT, in a single examination, can offer pulmonary vascular volume ratio in addition to pulmonary artery anatomy essential for evaluating peripheral pulmonary artery stenosis in patients with congenital heart disease. However there is a wide range of agreement between cardiac CT and lung perfusion scintigraphy. (orig.)

  3. Pulmonary vascular volume ratio measured by cardiac computed tomography in children and young adults with congenital heart disease: comparison with lung perfusion scintigraphy

    International Nuclear Information System (INIS)

    Goo, Hyun Woo; Park, Sang Hyub

    2017-01-01

    Lung perfusion scintigraphy is regarded as the gold standard for evaluating differential lung perfusion ratio in congenital heart disease. To compare cardiac CT with lung perfusion scintigraphy for estimated pulmonary vascular volume ratio in patients with congenital heart disease. We included 52 children and young adults (median age 4 years, range 2 months to 28 years; 31 males) with congenital heart disease who underwent cardiac CT and lung perfusion scintigraphy without an interim surgical or transcatheter intervention and within 1 year. We calculated the right and left pulmonary vascular volumes using threshold-based CT volumetry. Then we compared right pulmonary vascular volume percentages at cardiac CT with right lung perfusion percentages at lung perfusion scintigraphy by using paired t-test and Bland-Altman analysis. The right pulmonary vascular volume percentages at cardiac CT (66.3 ± 14.0%) were significantly smaller than the right lung perfusion percentages at lung perfusion scintigraphy (69.1 ± 15.0%; P=0.001). Bland-Altman analysis showed a mean difference of -2.8 ± 5.8% and 95% limits of agreement (-14.1%, 8.5%) between these two variables. Cardiac CT, in a single examination, can offer pulmonary vascular volume ratio in addition to pulmonary artery anatomy essential for evaluating peripheral pulmonary artery stenosis in patients with congenital heart disease. However there is a wide range of agreement between cardiac CT and lung perfusion scintigraphy. (orig.)

  4. Utilizing Forced Vital Capacity to Predict Low Lung Compliance and Select Intraoperative Tidal Volume During Thoracic Surgery.

    Science.gov (United States)

    Hoftman, Nir; Eikermann, Eric; Shin, John; Buckley, Jack; Navab, Kaveh; Abtin, Fereidoun; Grogan, Tristan; Cannesson, Maxime; Mahajan, Aman

    2017-12-01

    Tidal volume selection during mechanical ventilation utilizes dogmatic formulas that only consider a patient's predicted body weight (PBW). In this study, we investigate whether forced vital capacity (FVC) (1) correlates better to total lung capacity (TLC) than PBW, (2) predicts low pulmonary compliance, and (3) provides an alternative method for tidal volume selection. One hundred thirty thoracic surgery patients had their preoperative TLC calculated via 2 methods: (1) pulmonary function test (PFT; TLCPFT) and (2) computed tomography 3D reconstruction (TLCCT). We compared the correlation between TLC and PBW with the correlation between TLC and FVC to determine which was stronger. Dynamic pulmonary compliance was then calculated from intraoperative ventilator data and logistic regression models constructed to determine which clinical measure best predicted low compliance. Ratios of tidal volume/FVC plotted against peak inspiratory pressure were utilized to construct a new model for tidal volume selection. Calculated tidal volumes generated by this model were then compared with those generated by the standard lung-protective formula Vt = 7 cc/kg. The correlation between FVC and TLC (0.82 for TLCPFT and 0.76 for TLCCT) was stronger than the correlation between PBW and TLC (0.65 for TLCPFT and 0.58 for TLCCT). Patients with very low compliance had significantly smaller lung volumes (forced expiratory volume at 1 second, FVC, TLC) and lower diffusion capacity of the lungs for carbon monoxide when compared with patients with normal compliance. An FVC cutoff of 3470 cc was 100% sensitive and 51% specific for predicting low compliance. The proposed equation Vt = FVC/8 significantly reduced calculated tidal volume by a mean of 22.5% in patients with low pulmonary compliance without affecting the mean tidal volume in patients with normal compliance (mean difference 0.9%). FVC is more strongly correlated to TLC than PBW and a cutoff of about 3.5 L can be utilized to predict

  5. Can simulation measurements be used to predict the irradiated lung volume in the tangential fields in patients treated for breast cancer

    International Nuclear Information System (INIS)

    Bornstein, B.A.; Cheng, C.W.; Rhodes, L.M.; Rashid, H.; Stomper, P.C.; Siddon, R.L.; Harris, J.R.

    1990-01-01

    A simple method of estimating the amount of lung irradiated in patients with breast cancer would be of use in minimizing lung complications. To determine whether simple measurements taken at the time of simulation can be used to predict the lung volume in the radiation field, we performed CT scans as part of treatment planning in 40 cases undergoing radiotherapy for breast cancer. Parameters measured from simulator films included: (a) the perpendicular distance from the posterior tangential field edge to the posterior part of the anterior chest wall at the center of the field (CLD); (b) the maximum perpendicular distance from the posterior tangential field edge to the posterior part of the anterior chest wall (MLD); and (c) the length of lung (L) as measured at the posterior tangential field edge on the simulator film. CT scans of the chest were performed with the patient in the treatment position with 1 cm slice intervals, covering lung apex to base. The ipsilateral total lung area and the lung area included within the treatment port were calculated for each CT scan slice, multiplied by the slice thickness, and then integrated over all CT scan slices to give the volumes. The best predictor of the percent of ipsilateral lung volume treated by the tangential fields was the CLD. Employing linear regression analysis, a coefficient of determination r2 = 0.799 was calculated between CLD and percent treated ipsilateral lung volume on CT scan. In comparison, the coefficients for the other parameters were r2 = 0.784 for the MLD, r2 = 0.071 for L, and r2 = 0.690 for CLD x L. A CLD of 1.5 cm predicted that about 6% of the ipsilateral lung would be included in the tangential field, a CLD of 2.5 cm about 16%, and a CLD of 3.5 cm about 26% of the ipsilateral lung, with a mean 90% prediction interval of +/- 7.1% of ipsilateral lung volume

  6. Transpulmonary pressures and lung mechanics with glossopharyngeal insufflation and exsufflation beyond normal lung volumes in competitive breath-hold divers.

    Science.gov (United States)

    Loring, Stephen H; O'Donnell, Carl R; Butler, James P; Lindholm, Peter; Jacobson, Francine; Ferrigno, Massimo

    2007-03-01

    Throughout life, most mammals breathe between maximal and minimal lung volumes determined by respiratory mechanics and muscle strength. In contrast, competitive breath-hold divers exceed these limits when they employ glossopharyngeal insufflation (GI) before a dive to increase lung gas volume (providing additional oxygen and intrapulmonary gas to prevent dangerous chest compression at depths recently greater than 100 m) and glossopharyngeal exsufflation (GE) during descent to draw air from compressed lungs into the pharynx for middle ear pressure equalization. To explore the mechanical effects of these maneuvers on the respiratory system, we measured lung volumes by helium dilution with spirometry and computed tomography and estimated transpulmonary pressures using an esophageal balloon after GI and GE in four competitive breath-hold divers. Maximal lung volume was increased after GI by 0.13-2.84 liters, resulting in volumes 1.5-7.9 SD above predicted values. The amount of gas in the lungs after GI increased by 0.59-4.16 liters, largely due to elevated intrapulmonary pressures of 52-109 cmH(2)O. The transpulmonary pressures increased after GI to values ranging from 43 to 80 cmH(2)O, 1.6-2.9 times the expected values at total lung capacity. After GE, lung volumes were reduced by 0.09-0.44 liters, and the corresponding transpulmonary pressures decreased to -15 to -31 cmH(2)O, suggesting closure of intrapulmonary airways. We conclude that the lungs of some healthy individuals are able to withstand repeated inflation to transpulmonary pressures far greater than those to which they would normally be exposed.

  7. Variation of gross tumor volume and clinical target volume definition for lung cancer

    International Nuclear Information System (INIS)

    Liang Jun; Li Minghui; Chen Dongdu

    2011-01-01

    Objective: To study the variation of gross tumor volume (GTV) and clinical target volume (CTV) definition for lung cancer between different doctors. Methods: Ten lung cancer patients with PET-CT simulation were selected from January 2008 to December 2009.GTV and CTV of these patients were defined by four professors or associate professors of radiotherapy independently. Results: The mean ratios of largest to smallest GTV and CTV were 1.66 and 1.65, respectively. The mean coefficients of variation for GTV and CTV were 0.20 and 0.17, respectively. System errors of CTV definition in three dimension were less than 5 mm, which was the largest in inferior and superior (0.48 cm, 0.37 cm, 0.32 cm; F=0.40, 0.60, 0.15, P=0.755, 0.618, 0.928). Conclusions: The variation of GTV and CTV definition for lung cancer between different doctors exist. The mean ratios of largest to smallest GTV and CTV were less than 1.7. The variation was in hilar and mediastinum lymphanode regions. System error of CTV definition was the largest (<5 mm) in cranio-caudal direction. (authors)

  8. The lung volume reduction coil for the treatment of emphysema : a new therapy in development

    NARCIS (Netherlands)

    Klooster, Karin; ten Hacken, Nick H. T.; Slebos, Dirk-Jan

    Lung volume reduction (LVR) coil treatment is a novel therapy for patients with severe emphysema. In this bilateral bronchoscopic treatment, approximately 10 LVR coils per lobe are delivered under fluoroscopic guidance in two sequential procedures. The LVR coil reduces lung volume by compressing the

  9. Bronchoscopic Lung Volume Reduction Coil Treatment of Patients With Severe Heterogeneous Emphysema

    NARCIS (Netherlands)

    Slebos, Dirk-Jan; Klooster, Karin; Ernst, Armin; Herth, Felix J. F.; Kerstjens, Huib A. M.

    Background: The lung volume reduction coil (LVR-coil), a new experimental device to achieve lung volume reduction by bronchoscopy in patients with severe emphysema, works in a manner unaffected by collateral airflow. We investigated the safety and efficacy of LVR-coil treatment in patients with

  10. Dependent lung opacity at thin-section CT: evaluation by spirometrically-gated CT of the influence of lung volume

    International Nuclear Information System (INIS)

    Lee, Ki Nam; Yoon, Seong Kuk; Sohn, Choon Hee; Choi, Pil Jo; Webb, W. Richard

    2002-01-01

    To evaluate the influence of lung volume on dependent lung opacity seen at thin-section CT. In thirteen healthy volunteers, thin-section CT scans were performed at three levels (upper, mid, and lower portion of the lung) and at different lung volumes (10, 30, 50, and 100% vital capacity), using spirometric gated CT. Using a three-point scale, two radiologists determined whether dependent opacity was present, and estimated its degree. Regional lung attenuation at a level 2 cm above the diaphragm was determined using semiautomatic segmentation, and the diameter of a branch of the right lower posterior basal segmental artery was measured at each different vital capacity. At all three anatomic levels, dependent opacity occurred significantly more often at lower vital capacities (10, 30%) than at 100% vital capacity (p = 0.001). Visually estimated dependent opacity was significantly related to regional lung attenuation (p < 0.0001), which in dependent areas progressively increased as vital capacity decreased (p < 0.0001). The presence of dependent opacity and regional lung attenuation of a dependent area correlated significantly with increased diameter of a segmental arterial branch (r = 0.493 and p = 0.0002; r = 0.486 and p 0.0003, respectively). Visual estimation and CT measurements of dependent opacity obtained by semiautomatic segmentation are significantly influenced by lung volume and are related to vascular diameter

  11. Simulation of lung cancer treatment with equivalent dose calculation and analysis of the dose distribution profile

    International Nuclear Information System (INIS)

    Thalhofer, J. L.; Marques L, J.; Da Silva, A. X.; Dos Reis J, J. P.; Da Silva J, W. F. R.; Arruda C, S. C.; Monteiro de S, E.; Santos B, D. V.

    2017-10-01

    Actually, lung cancer is one of the most lethal types, due to the disease in the majority of the cases asymptomatic in the early stages, being the detection of the pathology in advanced stage, with tumor considerable volume. Dosimetry analysis of healthy organs under real conditions is not feasible. Therefore, computational simulations are used to auxiliary in dose verification in organs of patients submitted to radiotherapy. The goal of this study is to calculate the equivalent dose, due to photons, in surrounding in healthy organs of a patient submitted to radiotherapy for lung cancer, through computational modeling. The simulation was performed using the MCNPX code (Version, 2006], Rex and Regina phantom [ICRP 110, 2008], radiotherapy room, Siemens Oncor Expression accelerator operating at 6 MV and treatment protocol adopted at the Inca (National Cancer Institute, Brazil). The results obtained, considering the dose due to photons for both phantom indicate that organs located inside the thoracic cavity received higher dose, being the bronchi, heart and esophagus more affected, due to the anatomical positioning. Clinical data describe the development of bronchiolitis, esophagitis, and cardiomyopathies with decreased cardiopulmonary function as one of the major effects of lung cancer treatment. In the Regina phantom, the second largest dose was in the region of the breasts with 615,73 mSv / Gy, while in the Rex 514,06 mSv / Gy, event related to the difference of anatomical structure of the organ. Through the t mesh command, a qualitative analysis was performed between the dose deposition profile of the planning system and the simulated treatment, with a similar profile of the dose distribution being verified along the patients body. (Author)

  12. Finite volume thermal-hydraulics and neutronics coupled calculations - 15300

    International Nuclear Information System (INIS)

    Araujo Silva, V.; Campagnole dos Santos, A.A.; Mesquit, A.Z.; Bernal, A.; Miro, R.; Verdu, G.; Pereira, C.

    2015-01-01

    The computational power available nowadays allows the coupling of neutronics and thermal-hydraulics codes for reactor studies. The present methodology foresees at least one constraint to the separated codes in order to perform coupled calculations: both codes must use the same geometry, however, meshes can be different for each code as long as the internal surfaces stays the same. Using the finite volume technique, a 3D diffusion nodal code was implemented to deal with neutron transport. This code can handle non-structured meshes which allows for complicated geometries calculations and therefore more flexibility. A computational fluid dynamics (CFD) code was used in order to obtain the same level of details for the thermal hydraulics calculations. The chosen code is OpenFOAM, an open-source CFD tool. Changes in OpenFOAM allow simple coupled calculations of a PWR fuel rod with neutron transport code. OpenFOAM sends coolant density information and fuel temperature to the neutron transport code that sends back power information. A mapping function is used to average values when one node in one side corresponds to many nodes in the other side. Data is exchanged between codes by library calls. As the results of a fuel rod calculations progress, more complicated and processing demanding geometries will be simulated, aiming to the simulation of a real scale PWR fuel assembly

  13. Radionuclide-determined changes in pulmonary blood volume and thallium lung uptake in patients with coronary artery disease

    International Nuclear Information System (INIS)

    Wilson, R.A.; Okada, R.D.; Boucher, C.A.; Strauss, H.W.; Pohost, G.M.

    1983-01-01

    Exercise-induced increases in radionuclide-determined pulmonary blood volume (PBV) and thallium lung uptake have been described in patients with coronary artery disease (CAD) and have been shown to correlate with transient exercise-induced left ventricular dysfunction. To compare these 2 techniques in the same patients, 74 patients (59 with and 15 without significant CAD) underwent supine bicycle exercise twice on the same day--first for thallium myocardial and lung imaging and then for technetium-99m gated blood pool imaging for the PBV ratio determination. Thallium activity of lung and myocardium was determined to calculate thallium lung/heart ratio. Relative changes in PBV from rest to exercise were expressed as a ratio of pulmonary counts (exercise/rest). Previously reported normal ranges for thallium lung/heart ratio and PBV ratio were used. The PBV ratio and thallium lung/heart ratio were abnormal in 71 and 36%, respectively, of patients with CAD (p less than 0.01). Both ratios were normal in all patients without CAD. Although the resting ejection fractions did not differ significantly in patients with normal versus those with abnormal PBV ratios or thallium lung/heart ratios, abnormal PBV ratios and thallium lung/heart ratios were associated with an exercise-induced decrease in ejection fraction. Propranolol use was significantly higher in patients with abnormal than in those with normal thallium lung/heart ratios (p less than 0.01). No significant difference in propranolol use was present in patients with abnormal or normal PBV ratios. In conclusion: (1) the prevalence of an abnormal thallium lung/heart ratio is less than that of the PBV ratio in patients with CAD; (2) both tests are normal in normal control subjects; (3) propranolol does not cause abnormal results in normal control subjects; however, propranolol may influence lung thallium uptake in patients with CAD; and (4) when both tests are abnormal, there is a high likelihood of multivessel disease

  14. Calculation of Steam Volume Fraction in Subcooled Boiling

    Energy Technology Data Exchange (ETDEWEB)

    Rouhani, S Z

    1967-06-15

    An analysis of subcooled boiling is presented. It is assumed that heat is removed by vapor generation, heating of the liquid that replaces the detached bubbles, and to some extent by single phase heat transfer. Two regions of subcooled boiling are considered and a criterion is provided for obtaining the limiting value of subcooling between the two regions. Condensation of vapor in the subcooled liquid is analysed and the relative velocity of vapor with respect to the liquid is neglected in these regions. The theoretical arguments result in some equations for the calculation of steam volume fraction and true liquid subcooling.

  15. Fetal lung volume in congenital diaphragmatic hernia: association of prenatal MR imaging findings with postnatal chronic lung disease.

    Science.gov (United States)

    Debus, Angelika; Hagelstein, Claudia; Kilian, A Kristina; Weiss, Christel; Schönberg, Stefan O; Schaible, Thomas; Neff, K Wolfgang; Büsing, Karen A

    2013-03-01

    To assess whether chronic lung disease (CLD) in surviving infants with congenital diaphragmatic hernia (CDH) is associated with lung hypoplasia on the basis of the results of antenatal observed-to-expected fetal lung volume (FLV) ratio measurement at magnetic resonance (MR) imaging. The study received approval from the institutional review board, with waiver of informed consent for this retrospective review from patients who had previously given informed consent for prospective studies. The ratio of observed to expected FLV at MR imaging was calculated in 172 fetuses with CDH. At postpartum day 28, the need for supplemental oxygen implicated the diagnosis of CLD. At day 56, patients with CLD were assigned to one of three groups-those with mild, moderate, or severe CLD-according to their demand for oxygen. Logistic regression analysis was used to assess the prognostic value of the individual observed-to-expected FLV ratio for association with postnatal development of CLD. Children with CLD were found to have significantly smaller observed-to-expected FLV ratios at MR imaging than infants without CLD (P CLD revealed significant differences in observed-to-expected FLV ratio between patients with mild CLD and those with moderate (P = .012) or severe (P = .007) CLD. For an observed-to-expected FLV ratio of 5%, 99% of patients with CDH developed CLD, compared with less than 5% of fetuses with an observed-to-expected FLV ratio of 50%. Perinatally, development and grade of CLD were further influenced by the need for extracorporeal membrane oxygenation (ECMO) (P CLD in surviving infants with CDH is associated with the prenatally determined observed-to-expected FLV ratio. Early neonatal therapeutic decisions can additionally be based on this ratio. Perinatally, ECMO requirement and gestational age at delivery are useful in further improving the estimated probability of CLD.

  16. Incidental lung volume reduction following fulminant pulmonary hemorrhage in a patient with severe emphysema.

    Science.gov (United States)

    Hetzel, Juergen; Spengler, Werner; Horger, Marius; Boeckeler, Michael

    2015-06-01

    Endoscopic lung volume reduction is an emerging technique meant to improve lung function parameters, quality of life, and exercise tolerance in patients with severe lung emphysema. This is the first report of lung volume reduction by autologous blood in a patient with non-bullous lung emphysema. A 74-year-old woman with heterogeneous lung emphysema developed accidentally diffuse lobar bleeding immediately after valve placement. Due to persistent hemorrhage, the valves had to be removed shortly thereafter. Despite extraction of the valves, respiratory function of the patient improved rapidly indicated also by a drop in the COPD assessment test questionnaire, 3 months later. This was consistent with both improvement of lung function tests and six-minute walking test.

  17. Volume Oscillations Delivered to a Lung Model Using 4 Different Bubble CPAP Systems.

    Science.gov (United States)

    Poli, Jonathan A; Richardson, C Peter; DiBlasi, Robert M

    2015-03-01

    High-frequency pressure oscillations created by gas bubbling through an underwater seal during bubble CPAP may enhance ventilation and aid in lung recruitment in premature infants. We hypothesized that there are no differences in the magnitude of oscillations in lung volume (ΔV) in a preterm neonatal lung model when different bubble CPAP systems are used. An anatomically realistic replica of an infant nasal airway model was attached to a Silastic test lung sealed within a calibrated plethysmograph. Nasal prongs were affixed to the simulated neonate and supported using bubble CPAP systems set at 6 cm H2O. ΔV was calculated using pressure measurements obtained from the plethysmograph. The Fisher & Paykel Healthcare bubble CPAP system provided greater ΔV than any of the other devices at all of the respective bias flows (P CPAP systems. The magnitude of ΔV increased at bias flows of > 4 L/min in the Fisher & Paykel Healthcare, Airways Development, and homemade systems, but appeared to decrease as bias flow increased with the Babi.Plus system. The major finding of this study is that bubble CPAP can provide measureable ventilation effects in an infant lung model. We speculate that the differences noted in ΔV between the different devices are a combination of the circuit/nasal prong configuration, bubbler configuration, and frequency of oscillations. Additional testing is needed in spontaneously breathing infants to determine whether a physiologic benefit exists when using the different bubble CPAP systems. Copyright © 2015 by Daedalus Enterprises.

  18. Cross-sectional changes in lung volume measured by electrical impedance tomography are representative for the whole lung in ventilated preterm infants

    NARCIS (Netherlands)

    van der Burg, Pauline S.; Miedema, Martijn; de Jongh, Franciscus H.C.; Frerichs, Inez; van Kaam, Anton H.

    2014-01-01

    Objective: Electrical impedance tomography measures lung volume in a cross-sectional slice of the lung. Whether these cross-sectional volume changes are representative of the whole lung has only been investigated in adults, showing conflicting results. This study aimed to compare cross-sectional and

  19. Ethical and equity issues in lung transplantation and lung volume reduction surgery.

    Science.gov (United States)

    Glanville, A R

    2006-01-01

    New medical and scientific disciplines are often developed in haste with rampant enthusiasm and scant regard for the balance between action and thoughtful deliberation. Driven by the desire to prolong life and provide a better quality of life for desperately sick individuals, the twin modalities of lung transplantation and lung volume reduction therapy have only just reached their majority. Both are invested with the capacity to help and to harm so it is right to consider carefully their ethical and equitable distribution. Much has been learned in the last 20 years to assist in these deliberations. First, how can we ensure equity of access to transplant services and equality of outcomes? How do we balance resource allocation of a precious and scarce resource with individual recipient needs? Does the concept of distributive justice prevail in our daily work in this field? How do we honour the donor and their family? How do we as practitioners avoid ethical dilemmas related to personal bias and justifiable reward for services rendered? Finally, how do we learn to incorporate ethical forethought and planning guided by experts in the area into everyday behaviour?

  20. Lung volume reduction surgery: an overview Cirurgia redutora de volume pulmonar: uma revisão

    Directory of Open Access Journals (Sweden)

    Rodrigo Afonso da Silva Sardenberg

    2010-01-01

    Full Text Available This study intends to review the literature on the efficacy, safety and feasibility of lung volume reduction surgery (LVRS in patients with advanced emphysema. Studies on LVRS from January 1995 to December 2009 were included by using Pubmed (MEDLINE and Cochrane Library literature in English. Search words such as lung volume reduction surgery or lung reduction surgery, pneumoplasty or reduction pneumoplasty, COPD or chronic obstructive pulmonary disease and surgery, were used. We also compared medical therapy and surgical technique. Studies consisting of randomized controlled trials, controlled clinical trials (randomized and nonrandomized, reviews and case series were analyzed. Questions regarding validity of the early clinical reports, incomplete follow-up bias, selection criteria and survival, confounded the interpretation of clinical data on LVRS. Patients with upper, lower and diffuse distribution of emphysema were included; we also analyzed as key points perioperative morbidity and mortality and lung function measurement as FEV1. Bullous emphysema was excluded from this review. Surgical approach included median sternotomy, unilateral or bilateral thoracotomy, and videothoracoscopy with stapled or laser ablation. Results of prospective randomized trials between medical management and LVRS are essential before final assessment can be established.O objetivo deste estudo é revisar a literatura acerca da eficácia, segurança e viabilidade da cirurgia redutora de volume pulmonar (CRVP em pacientes com enfisema pulmonar avançado. Estudos de CRVP de janeiro de 1995 a dezembro de 2009 foram incluídos através de pesquisa na Pubmed (MEDLINE e Cochrane Library, na literatura inglesa. Palavras de busca tais como lung volume reduction surgery ou lung reduction surgery, pneumoplasty ou reduction pneumoplasty, COPD ou chronic obstructive pulmonary disease e surgery foram utilizadas. Também realizamos comparação entre terapia médica e cir

  1. Evaluation of Neonatal Lung Volume Growth by Pulmonary Magnetic Resonance Imaging in Patients with Congenital Diaphragmatic Hernia.

    Science.gov (United States)

    Schopper, Melissa A; Walkup, Laura L; Tkach, Jean A; Higano, Nara S; Lim, Foong Yen; Haberman, Beth; Woods, Jason C; Kingma, Paul S

    2017-09-01

    To evaluate postnatal lung volume in infants with congenital diaphragmatic hernia (CDH) and determine if a compensatory increase in lung volume occurs during the postnatal period. Using a novel pulmonary magnetic resonance imaging method for imaging neonatal lungs, the postnatal lung volumes in infants with CDH were determined and compared with prenatal lung volumes obtained via late gestation magnetic resonance imaging. Infants with left-sided CDH (2 mild, 9 moderate, and 1 severe) were evaluated. The total lung volume increased in all infants, with the contralateral lung increasing faster than the ipsilateral lung (mean ± SD: 4.9 ± 3.0 mL/week vs 3.4 ± 2.1 mL/week, P = .005). In contrast to prenatal studies, the volume of lungs of infants with more severe CDH grew faster than the lungs of infants with more mild CDH (Spearman's ρ=-0.086, P = .01). Although the contralateral lung volume grew faster in both mild and moderate groups, the majority of total lung volume growth in moderate CDH came from increased volume of the ipsilateral lung (42% of total lung volume increase in the moderate group vs 32% of total lung volume increase in the mild group, P = .09). Analysis of multiple clinical variables suggests that increased weight gain was associated with increased compensatory ipsilateral lung volume growth (ρ = 0.57, P = .05). These results suggest a potential for postnatal catch-up growth in infants with pulmonary hypoplasia and suggest that weight gain may increase the volume growth of the more severely affected lung. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. SU-F-T-150: Comparing Normal Tissue Irradiated Volumes for Proton Vs. Photon Treatment Plans On Lung Patients

    Energy Technology Data Exchange (ETDEWEB)

    Liu, A; Mohan, R; Liao, Z [UT MD Anderson Cancer Center, Houston, TX (United States)

    2016-06-15

    Purpose: The aim of this work is to compare the “irradiated volume” (IRV) of normal tissues receiving 5, 20, 50, 80 and 90% or higher of the prescription dose with passively scattered proton therapy (PSPT) vs. IMRT of lung cancer patients. The overall goal of this research is to understand the factors affecting outcomes of a randomized PSPT vs. IMRT lung trial. Methods: Thirteen lung cancer patients, selected randomly, were analyzed. Each patient had PSPT and IMRT 74 Gy (RBE) plans meeting the same normal tissue constraints generated. IRVs were created for pairs of IMRT and PSPT plans on each patient. The volume of iGTV, (respiratory motion-incorporated GTV) was subtracted from each IRV to create normal tissue irradiated volume IRVNT. The average of IRVNT DVHs over all patients was also calculated for both modalities and inter-compared as were the selected dose-volume indices. Probability (p value) curves were calculated based on the Wilcoxon matched-paired signed-rank test to determine the dose regions where the statistically significant differences existed. Results: As expected, the average 5, 20 and 50% IRVNT’s for PSPT was found to be significantly smaller than for IMRT (p < 0.001, 0.01, and 0.001 respectively). However, the average 90% IRVNT for PSPT was greater than for IMRT (p = 0.003) presumably due to larger penumbra of protons and the long range of protons in lower density media. The 80% IRVNT for PSPT was also larger but not statistically distinguishable (p = .224). Conclusion: PSPT modality has smaller irradiated volume at lower doses, but larger volume at high doses. A larger cohort of lung patients will be analyzed in the future and IRVNT of patients treated with PSPT and IMRT will be compared to determine if the irradiated volumes (the magnitude of “dose bath”) correlate with outcomes.

  3. Lung volume reduction of pulmonary emphysema: the radiologist task.

    Science.gov (United States)

    Milanese, Gianluca; Silva, Mario; Sverzellati, Nicola

    2016-03-01

    Several lung volume reduction (LVR) techniques have been increasingly evaluated in patients with advanced pulmonary emphysema, especially in the last decade. Radiologist plays a pivotal role in the characterization of parenchymal damage and, thus, assessment of eligibility criteria. This review aims to discuss the most common LVR techniques, namely LVR surgery, endobronchial valves, and coils LVR, with emphasis on the role of computed tomography (CT). Several trials have recently highlighted the importance of regional quantification of emphysema by computerized CT-based segmentation of hyperlucent parenchyma, which is strongly recommended for candidates to any LVR treatment. In particular, emphysema distribution pattern and fissures integrity are evaluated to tailor the choice of the most appropriate LVR technique. Furthermore, a number of CT measures have been tested for the personalization of treatment, according to imaging detected heterogeneity of parenchymal disease. CT characterization of heterogeneous parenchymal abnormalities provides criteria for selection of the preferable treatment in each patient and improves outcome of LVR as reflected by better quality of life, higher exercise tolerance, and lower mortality.

  4. The Effect of Compartmental Asymmetry on the Monitoring of Pulmonary Mechanics and Lung Volumes.

    Science.gov (United States)

    Keenan, Joseph C; Cortes-Puentes, Gustavo A; Adams, Alexander B; Dries, David J; Marini, John J

    2016-11-01

    Esophageal pressure measurement for computation of transpulmonary pressure (P tp ) has begun to be incorporated into clinical use for evaluating forces across the lungs. Gaps exist in our understanding of how esophageal pressure (and therefore P tp ), a value measured at a single site, responds when respiratory system compartments are asymmetrically affected by whole-lung atelectasis or unilateral injury as well as changes in chest wall compliance. We reasoned that P tp would track with aerated volume changes as estimated by functional residual capacity (FRC) and tidal volume. We examined this hypothesis in the setting of asymmetric lungs and changes in intra-abdominal pressure. This study was conducted in the animal laboratory of a university-affiliated hospital. Models of unilateral atelectasis and unilateral and bilateral lung injury exposed to intra-abdominal hypertension (IAH) in 10 deeply sedated mechanically ventilated swine. Atelectasis was created by balloon occlusion of the left main bronchus. Unilateral lung injury was induced by saline lavage of isolated right lung. Diffuse lung injury was induced by saline lavage of both lungs. The peritoneum was insufflated with air to create a model of pressure-regulated IAH. We measured esophageal pressures, airway pressures, FRC by gas dilution, and oxygenation. FRC was reduced by IAH in normal lungs (P volume in the setting of thoracic asymmetry and changes in intra-abdominal pressure. However, used alone, it cannot distinguish the relative contributions of air-space distention and recruitment of lung units. Copyright © 2016 by Daedalus Enterprises.

  5. [Normal lung volumes in patients with idiopathic pulmonary fibrosis and emphysema].

    Science.gov (United States)

    Casas, Juan Pablo; Abbona, Horacio; Robles, Adriana; López, Ana María

    2008-01-01

    Pulmonary function tests in idiopathic pulmonary fibrosis characteristically show a restrictive pattern, resulting from reduction of pulmonary compliance due to diffuse fibrosis. Conversely, an obstructive pattern with hyperinflation results in emphysema by loss of elastic recoil, expiratory collapse of the peripheral airways and air trapping. Previous reports suggest that when both diseases coexist, pulmonary volumes are compensated and a smaller than expected reduction or even normal lung volumes can be found. We report 4 male patients of 64, 60, 73 and 70 years, all with heavy cigarette smoking history and progressive breathlessness. Three of them had severe limitation in their quality of life. All four showed advanced lung interstitial involvement, at high resolution CT scan, fibrotic changes predominantly in the subpleural areas of lower lung fields and concomitant emphysema in the upper lobes. Emphysema and pulmonary fibrosis was confirmed by open lung biopsy in one patient. The four patients showed normal spirometry and lung volumes with severe compromise of gas exchange and poor exercise tolerance evaluated by 6 minute walk test. Severe pulmonary arterial hypertension was also confirmed in three patients. Normal lung volumes does not exclude diagnosis of idiopathic pulmonary fibrosis in patients with concomitant emphysema. The relatively preserved lung volumes may underestimate the severity of idiopathic pulmonary fibrosis and attenuate its effects on lung function parameters.

  6. Density overwrites of internal tumor volumes in intensity modulated proton therapy plans for mobile lung tumors

    Science.gov (United States)

    Botas, Pablo; Grassberger, Clemens; Sharp, Gregory; Paganetti, Harald

    2018-02-01

    The purpose of this study was to investigate internal tumor volume density overwrite strategies to minimize intensity modulated proton therapy (IMPT) plan degradation of mobile lung tumors. Four planning paradigms were compared for nine lung cancer patients. Internal gross tumor volume (IGTV) and internal clinical target volume (ICTV) structures were defined encompassing their respective volumes in every 4DCT phase. The paradigms use different planning CT (pCT) created from the average intensity projection (AIP) of the 4DCT, overwriting the density within the IGTV to account for movement. The density overwrites were: (a) constant filling with 100 HU (C100) or (b) 50 HU (C50), (c) maximum intensity projection (MIP) across phases, and (d) water equivalent path length (WEPL) consideration from beam’s-eye-view. Plans were created optimizing dose-influence matrices calculated with fast GPU Monte Carlo (MC) simulations in each pCT. Plans were evaluated with MC on the 4DCTs using a model of the beam delivery time structure. Dose accumulation was performed using deformable image registration. Interplay effect was addressed applying 10 times rescanning. Significantly less DVH metrics degradation occurred when using MIP and WEPL approaches. Target coverage (D99≥slant 70 Gy(RBE)) was fulfilled in most cases with MIP and WEPL (D{{99}WEPL}=69.2+/- 4.0 Gy (RBE)), keeping dose heterogeneity low (D5-D{{95}WEPL}=3.9+/- 2.0 Gy(RBE)). The mean lung dose was kept lowest by the WEPL strategy, as well as the maximum dose to organs at risk (OARs). The impact on dose levels in the heart, spinal cord and esophagus were patient specific. Overall, the WEPL strategy gives the best performance and should be preferred when using a 3D static geometry for lung cancer IMPT treatment planning. Newly available fast MC methods make it possible to handle long simulations based on 4D data sets to perform studies with high accuracy and efficiency, even prior to individual treatment planning.

  7. Is a reduction in radiation lung volume and dose necessary with paclitaxel chemotherapy for node-positive breast cancer?

    Science.gov (United States)

    Taghian, Alphonse G; Assaad, Sherif I; Niemierko, Andrzej; Floyd, Scott R; Powell, Simon N

    2005-06-01

    of RP was paclitaxel treatment. The use of paclitaxel chemotherapy and RT in the primary treatment of node-positive breast cancer is likely to increase the incidence of RP. In patients treated with paclitaxel, reducing the percentage of lung irradiated by 24% should reduce the risk of RP to 1%, according to our calculations of lung tolerance. Future clinical trials using combination CHT that includes paclitaxel and RT should carefully evaluate the incidence and severity of RP and should also accurately monitor the extent of lung included within the RT volume to develop safe guidelines for the delivery of what is becoming standard therapy for node-positive breast cancer.

  8. Radiobiological impact of dose calculation algorithms on biologically optimized IMRT lung stereotactic body radiation therapy plans

    International Nuclear Information System (INIS)

    Liang, X.; Penagaricano, J.; Zheng, D.; Morrill, S.; Zhang, X.; Corry, P.; Griffin, R. J.; Han, E. Y.; Hardee, M.; Ratanatharathom, V.

    2016-01-01

    The aim of this study is to evaluate the radiobiological impact of Acuros XB (AXB) vs. Anisotropic Analytic Algorithm (AAA) dose calculation algorithms in combined dose-volume and biological optimized IMRT plans of SBRT treatments for non-small-cell lung cancer (NSCLC) patients. Twenty eight patients with NSCLC previously treated SBRT were re-planned using Varian Eclipse (V11) with combined dose-volume and biological optimization IMRT sliding window technique. The total dose prescribed to the PTV was 60 Gy with 12 Gy per fraction. The plans were initially optimized using AAA algorithm, and then were recomputed using AXB using the same MUs and MLC files to compare with the dose distribution of the original plans and assess the radiobiological as well as dosimetric impact of the two different dose algorithms. The Poisson Linear-Quadatric (PLQ) and Lyman-Kutcher-Burman (LKB) models were used for estimating the tumor control probability (TCP) and normal tissue complication probability (NTCP), respectively. The influence of the model parameter uncertainties on the TCP differences and the NTCP differences between AAA and AXB plans were studied by applying different sets of published model parameters. Patients were grouped into peripheral and centrally-located tumors to evaluate the impact of tumor location. PTV dose was lower in the re-calculated AXB plans, as compared to AAA plans. The median differences of PTV(D 95% ) were 1.7 Gy (range: 0.3, 6.5 Gy) and 1.0 Gy (range: 0.6, 4.4 Gy) for peripheral tumors and centrally-located tumors, respectively. The median differences of PTV(mean) were 0.4 Gy (range: 0.0, 1.9 Gy) and 0.9 Gy (range: 0.0, 4.3 Gy) for peripheral tumors and centrally-located tumors, respectively. TCP was also found lower in AXB-recalculated plans compared with the AAA plans. The median (range) of the TCP differences for 30 month local control were 1.6 % (0.3 %, 5.8 %) for peripheral tumors and 1.3 % (0.5 %, 3.4 %) for centrally located tumors. The lower

  9. Absorbed dose calculation of the energy deposition close to bone, lung and soft tissue interfaces in molecular radiotherapy

    International Nuclear Information System (INIS)

    Fernandez, M.; Lassman, M.

    2015-01-01

    Full text of publication follows. Aim: for voxel-based dosimetry in molecular radiotherapy (MRT) based on tabulated voxel S-values these values are usually obtained only for soft tissue. In order to study the changes in the dose deposition patterns at interfaces between different materials we have performed Monte Carlo simulations. Methods: the deposited energy patterns were obtained using the Monte-Carlo radiation code MCNPX v2.7 for Lu 177 (medium-energy) and Y 90 (high-energy). The following interfaces were studied: soft tissue-bone and soft tissue-lungs. For this purpose a volume of soft tissue homogeneously filled with Lu 177 or Y 90 was simulated at the interface to 3 different volumes containing no activity: soft tissue, lungs and bone. The emission was considered to be isotropic. The dimensions were chosen to ensure that the energy deposited by all generated particles was scored. The materials were defined as recommended by ICPR46; the decay schemes of Eckerman and Endo were used. With these data the absorbed dose patterns normalized to the maximum absorbed dose in the source region (soft tissue) were calculated. Results: the absorbed dose fractions in the boundary with soft tissue, bone and lungs are 50%, 47% and 57%, respectively, for Lu 177 and 50%, 47% and 51% for Y 90 . The distances to the interface at which the absorbed fractions are at 0.1% are 1.0, 0.6 and 3.0 mm for Lu 177 and 7.0, 4.0 and 24 mm for Y 90 , for soft tissue, bone and lungs respectively. Conclusions: in MRT, the changes in the absorbed doses at interfaces between soft tissue and bone/lungs need to be considered for isotopes emitting high energy particles. (authors)

  10. Lung volumes related to physical activity, physical fitness, aerobic capacity and body mass index in students

    Directory of Open Access Journals (Sweden)

    Mihailova A.

    2016-01-01

    Reduced lung volumes were associated with lower aerobic fitness, lower physical fitness and lower amount of weekly physical activity. Healthier body mass index was associated with higher aerobic fitness (relative VO2max in both female and male.

  11. High procedure volume is strongly associated with improved survival after lung cancer surgery

    DEFF Research Database (Denmark)

    Lüchtenborg, Margreet; Riaz, Sharma P; Coupland, Victoria H

    2013-01-01

    Studies have reported an association between hospital volume and survival for non-small-cell lung cancer (NSCLC). We explored this association in England, accounting for case mix and propensity to resect....

  12. Changes in lung volume and ventilation during surfactant treatment in ventilated preterm infants

    NARCIS (Netherlands)

    Miedema, Martijn; de Jongh, Frans H.; Frerichs, Inez; van Veenendaal, Mariëtte B.; van Kaam, Anton H.

    2011-01-01

    The immediate and regional effects of exogenous surfactant in open lung high-frequency oscillatory ventilated (HFOV) preterm infants are unknown. To assess regional changes in lung volume, mechanics, and ventilation during and after surfactant administration in HFOV preterm infants with respiratory

  13. Transfer factor, lung volumes, resistance and ventilation distribution in healthy adults.

    Science.gov (United States)

    Verbanck, Sylvia; Van Muylem, Alain; Schuermans, Daniel; Bautmans, Ivan; Thompson, Bruce; Vincken, Walter

    2016-01-01

    Monitoring of chronic lung disease requires reference values of lung function indices, including putative markers of small airway function, spanning a wide age range.We measured spirometry, transfer factor of the lung for carbon monoxide (TLCO), static lung volume, resistance and ventilation distribution in a healthy population, studying at least 20 subjects per sex and per decade between the ages of 20 and 80 years.With respect to the Global Lung Function Initiative reference data, our subjects had average z-scores for forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC of -0.12, 0.04 and -0.32, respectively. Reference equations were obtained which could account for a potential dependence of index variability on age and height. This was done for (but not limited to) indices that are pertinent to asthma and chronic obstructive pulmonary disease studies: forced expired volume in 6 s, forced expiratory flow, TLCO, specific airway conductance, residual volume (RV)/total lung capacity (TLC), and ventilation heterogeneity in acinar and conductive lung zones.Deterioration in acinar ventilation heterogeneity and lung clearance index with age were more marked beyond 60 years, and conductive ventilation heterogeneity showed the greatest increase in variability with age. The most clinically relevant deviation from published reference values concerned RV/TLC values, which were considerably smaller than American Thoracic Society/European Respiratory Society-endorsed reference values. Copyright ©ERS 2016.

  14. Definition of gross tumor volume in lung cancer: inter-observer variability

    NARCIS (Netherlands)

    van de Steene, Jan; Linthout, Nadine; de Mey, Johan; Vinh-Hung, Vincent; Claassens, Cornelia; Noppen, Marc; Bel, Arjan; Storme, Guy

    2002-01-01

    BACKGROUND AND PURPOSE: To determine the inter-observer variation in gross tumor volume (GTV) definition in lung cancer, and its clinical relevance. MATERIALS AND METHODS: Five clinicians involved in lung cancer were asked to define GTV on the planning CT scan of eight patients. Resulting GTVs were

  15. Audiovisual biofeedback guided breath-hold improves lung tumor position reproducibility and volume consistency

    Directory of Open Access Journals (Sweden)

    Danny Lee, PhD

    2017-07-01

    Conclusions: This study demonstrated that audiovisual biofeedback can be used to improve the reproducibility and consistency of breath-hold lung tumor position and volume, respectively. These results may provide a pathway to achieve more accurate lung cancer radiation treatment in addition to improving various medical imaging and treatments by using breath-hold procedures.

  16. Numerical simulation of volume-controlled mechanical ventilated respiratory system with 2 different lungs.

    Science.gov (United States)

    Shi, Yan; Zhang, Bolun; Cai, Maolin; Zhang, Xiaohua Douglas

    2017-09-01

    Mechanical ventilation is a key therapy for patients who cannot breathe adequately by themselves, and dynamics of mechanical ventilation system is of great significance for life support of patients. Recently, models of mechanical ventilated respiratory system with 1 lung are used to simulate the respiratory system of patients. However, humans have 2 lungs. When the respiratory characteristics of 2 lungs are different, a single-lung model cannot reflect real respiratory system. In this paper, to illustrate dynamic characteristics of mechanical ventilated respiratory system with 2 different lungs, we propose a mathematical model of mechanical ventilated respiratory system with 2 different lungs and conduct experiments to verify the model. Furthermore, we study the dynamics of mechanical ventilated respiratory system with 2 different lungs. This research study can be used for improving the efficiency and safety of volume-controlled mechanical ventilation system. Copyright © 2016 John Wiley & Sons, Ltd.

  17. The irradiation lung volume in tangential fields for the treatment of a breast

    International Nuclear Information System (INIS)

    Oh, Y. T.; Kim, J. R.; Kang, H. J.; Sohn, J. H.; Kang, S. H.; Chun, M. S.

    1997-01-01

    Radiation pneumonitis is one of the complications caused by radiation therapy that includes a portion of the lung tissue. The severity of radiation induced pulmonary dysfunction depends on the irradiated lung volume, total dose, dose rate and underlying pulmonary function. The lung volume was measured for 25 patients with breast cancer irradiated with tangential field from Jan. 1995 to Aug. 1996. Parameters that can predict the irradiated lung volume included; (1) the perpendicular distance from the posterior tangential edge to the posterior part of the anterior chest wall at the center of the field (CLD); (2) the maximum perpendicular distance from the posterior tangential field edge to the posterior part of the anterior chest wall (MLD); (3) the greatest perpendicular distance from the posterior tangential edge to the posterior part of anterior chest wall on CT image at the center of the longitudinal field (GPD); (4) the length of the longitudinal field (L). The irradiated lung volume(RV), the entire both lung volume(EV) and the ipsilateral lung volume(IV) were measured using dose volume histogram. The RV is 61-279cc, the RV/EV is 2.9-13.0% and the RV/EN is 4.9-29.6%. The CLD, the MLD and the GPD are 1.9-3.3cm and 1.4-3.1cm respectively. The significant relations between the irradiated lung volume such as RV, RV/EV, RV/IV and parameters such as CLD, MLD, GPD, L, CLD x L, MLD x L and GPD x L are not found with little variances in parameters. The RV/IV of the left breast irradiation is significances. The significant relationship between the irradiated lung volume and predictors is not found with little variation on parameters. The irradiated lung volume in the tangential field is less than 10% of entire lung volume when CLD is less than 3cm. The RV/IV of the left tangential field is larger than that of the right but there was no significant differences in RV/EVs. Symptomatic radiation pneumonitis has not occurred during minimum 6 months follow up. (author)

  18. Volume doubling time of lung cancer detected in idiopathic interstitial pneumonia. Comparison with that in chronic obstructive pulmonary disease

    International Nuclear Information System (INIS)

    Kim, Cherry; Lee, Sang Min; Choe, Jooae; Chae, Eun Jin; Do, Kyung-Hyun; Seo, Joon Beom

    2018-01-01

    To assess the volume doubling time (VDT) of lung cancers in IIP compared with COPD. A total of 61 patients (32 with IIP and 29 with COPD) were identified. A radiologist performed three-dimensional manual segmentation for lung cancers. VDTs were calculated and compared between two groups. Logistic regression was performed to identify factors associated with rapid tumour growth (VDT < 90 days). The median VDT of lung cancers in IIP (78.2 days) was significantly shorter than that in COPD (126.1 days; p=0.004). Squamous cell carcinoma (SqCC) was the most frequent subtype, followed by small cell lung cancer (SCLC) in IIP. In COPD, SqCC was the most frequent subtype, followed by adenocarcinoma. Rapid tumour growth was observed in 20 cancers from IIP, and in nine cancers from COPD (p=0.021). SCLC was significantly correlated with rapid tumour growth (p=0.038). Multivariate analysis revealed that the presence of IIP was the single independent predictor of rapid tumour growth (p = 0.016; odds ratio, 3.7). Lung cancers in IIP showed more rapid growth, with median VDT < 90 days. Therefore, a shorter follow-up interval (<90 days) may be necessary when CT surveillance is considered in IIP patients with suspected lung cancer. (orig.)

  19. Effects of vertical positioning on gas exchange and lung volumes in acute respiratory distress syndrome.

    Science.gov (United States)

    Richard, Jean-Christophe M; Maggiore, Salvatore Maurizio; Mancebo, Jordi; Lemaire, François; Jonson, Bjorn; Brochard, Laurent

    2006-10-01

    Supine position may contribute to the loss of aerated lung volume in patients with acute respiratory distress syndrome (ARDS). We hypothesized that verticalization increases lung volume and improves gas exchange by reducing the pressure surrounding lung bases. Prospective observational physiological study in a medical ICU. In 16 patients with ARDS we measured arterial blood gases, pressure-volume curves of the respiratory system recorded from positive-end expiratory pressure (PEEP), and changes in lung volume in supine and vertical positions (trunk elevated at 45 degrees and legs down at 45 degrees ). Vertical positioning increased PaO(2) significantly from 94+/-33 to 142+/-49 mmHg, with an increase higher than 40% in 11 responders. The volume at 20 cmH(2)O measured on the PV curve from PEEP increased using the vertical position only in responders (233+/-146 vs. -8+/-9 1ml in nonresponders); this change was correlated to oxygenation change (rho=0.55). End-expiratory lung volume variation from supine to vertical and 1 h later back to supine, measured in 12 patients showed a significant increase during the 1-h upright period in responders (n=7) but not in nonresponders (n=5; 215+/-220 vs. 10+/-22 ml), suggesting a time-dependent recruitment. Vertical positioning is a simple technique that may improve oxygenation and lung recruitment in ARDS patients.

  20. Automatic segmentation of tumor-laden lung volumes from the LIDC database

    Science.gov (United States)

    O'Dell, Walter G.

    2012-03-01

    The segmentation of the lung parenchyma is often a critical pre-processing step prior to application of computer-aided detection of lung nodules. Segmentation of the lung volume can dramatically decrease computation time and reduce the number of false positive detections by excluding from consideration extra-pulmonary tissue. However, while many algorithms are capable of adequately segmenting the healthy lung, none have been demonstrated to work reliably well on tumor-laden lungs. Of particular challenge is to preserve tumorous masses attached to the chest wall, mediastinum or major vessels. In this role, lung volume segmentation comprises an important computational step that can adversely affect the performance of the overall CAD algorithm. An automated lung volume segmentation algorithm has been developed with the goals to maximally exclude extra-pulmonary tissue while retaining all true nodules. The algorithm comprises a series of tasks including intensity thresholding, 2-D and 3-D morphological operations, 2-D and 3-D floodfilling, and snake-based clipping of nodules attached to the chest wall. It features the ability to (1) exclude trachea and bowels, (2) snip large attached nodules using snakes, (3) snip small attached nodules using dilation, (4) preserve large masses fully internal to lung volume, (5) account for basal aspects of the lung where in a 2-D slice the lower sections appear to be disconnected from main lung, and (6) achieve separation of the right and left hemi-lungs. The algorithm was developed and trained to on the first 100 datasets of the LIDC image database.

  1. Lung and heart dose volume analyses with CT simulator in radiation treatment of breast cancer

    International Nuclear Information System (INIS)

    Das, Indra J.; Cheng, Elizabeth C.; Freedman, Gary; Fowble, Barbara

    1998-01-01

    Purpose: Radiation pneumonitis and cardiac effects are directly related to the irradiated lung and heart volumes in the treatment fields. The central lung distance (CLD) from a tangential breast radiograph is shown to be a significant indicator of ipsilateral irradiated lung volume. Retrospective analysis of the pattern of dose volume of lung and heart with actual volume data from a CT simulator in the treatment of breast cancer is presented with respect to CLD. Methods and Materials: The heart and lung volumes in the tangential treatment fields were analyzed in 108 consecutive cases (52 left and 56 right breast) referred for CT simulation. All patients in this study were immobilized and placed on an inclined breast board in actual treatment setup. Both arms were stretched over head to avoid collision with the scanner aperture. Radiopaque marks were placed on the medial and lateral borders of the tangential fields. All patients were scanned in spiral mode with slice width and thickness of 3 mm each, respectively. The lung and heart structures as well as irradiated areas were delineated on each slice and respective volumes were accurately measured. The treatment beam parameters were recorded and the digitally reconstructed radiographs (DRRs) were generated for the measurement of the CLD and analysis. Results: Using CT data the mean volume and standard deviation of left and right lungs were 1307.7 ± 297.7 cm 3 and 1529.6 ± 298.5 cm 3 , respectively. The magnitude of irradiated volume in left and right lung is nearly equal for the same CLD that produces different percent irradiated volumes (PIV). The left and right PIV lungs are 8.3 ± 4.7% and 6.6 ± 3.7%, respectively. The PIV data have shown to correlate with CLD with second- and third-degree polynomials; however, in this study a simple straight line regression is used to provide better confidence than the higher order polynomials. The regression lines for the left and right breasts are very different based on

  2. An evaluation of the feasibility of assessment of volume perfusion for the whole lung by 128-slice spiral CT

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Haitao [Imaging Center of Taian Central Hospital, Taian, Shandong (China); Gao, Fei; Li, Ning; Liu, Cheng [Shandong Univ., Shandong Medical Imaging Research Inst., CT Room, Shandong (China)], e-mail: liucheng491025@sina.com

    2013-10-15

    Background: Lung perfusion based on dynamic scanning cannot provide a quantitative assessment of the whole lung because of the limited coverage of the current computed tomography (CT) detector designs. Purpose: To evaluate the feasibility of dynamic volume perfusion CT (VPCT) of the whole lung using a 128-slice CT for the quantitative assessment and visualization of pulmonary perfusion. Material and Methods: Imaging was performed in a control group of 17 subjects who had no signs of disturbance of pulmonary function or diffuse lung disease, and 15 patients (five patients with acute pulmonary embolism and 10 with emphysema) who constituted the abnormal lung group. Dynamic VPCT was performed in all subjects, and pulmonary blood flow (PBF), pulmonary blood volume (PBV), and mean transit time (MTT) were calculated from dynamic contrast images with a coverage of 20.7 cm. Regional and volumetric PBF, PBV, and MTT were statistically evaluated and comparisons were made between the normal and abnormal lung groups. Results: Regional PBF (94.2{+-}36.5, 161.8 {+-}29.6, 185.7 {+-}38.1 and 125.5 {+-}46.1, 161.9 {+-}31.4, 169.3 {+-}51.7), PBV (6.7 {+-}2.8, 10.9 {+-}3.0, 12.9 {+-}4.5 and 9.9 {+-}4.6, 10.3 {+-}2.9, 11.9 {+-}4.5), and MTT (5.8 {+-}2.4, 4.5 {+-}1.3, 4.7 {+-}2.1 and 5.6 {+-}2.3, 4.3 {+-}1.5, 4.9 {+-}1.5) demonstrated significant differences in the gravitational and isogravitational directions in the normal lung group (P < 0.05). The PBF (154.2 {+-}30.6 vs. 94.9 {+-}15.9) and PBV (11.1 {+-}4.0 vs. 6.6 {+-}1.7) by dynamic VPCT showed significant differences between normal and abnormal lungs (P < 0.05), notwithstanding the four large lungs that had coverage > 20.7 cm. Conclusion: Dynamic VPCT of the whole lung is feasible for the quantitative assessment of pulmonary perfusion by 128-slice CT, and may in future permit the evaluation of both morphological and functional features of the whole lung in a single examination.

  3. Emphysema lung lobe volume reduction: effects on the ipsilateral and contralateral lobes

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Matthew S.; Kim, Hyun J.; Abtin, Fereidoun G.; Galperin-Aizenberg, Maya; Pais, Richard; Da Costa, Irene G.; Ordookhani, Arash; Chong, Daniel; Ni, Chiayi; McNitt-Gray, Michael F.; Goldin, Jonathan G. [David Geffen School of Medicine at UCLA, Center for Computer Vision and Imaging Biomarkers, Department of Radiological Sciences, Los Angeles, CA (United States); Strange, Charlie [Medical University of South Carolina, Department of Pulmonary and Critical Care Medicine, Columbia, SC (United States); Tashkin, Donald P. [David Geffen School of Medicine at UCLA, Division of Pulmonary and Critical Care Medicine, Los Angeles, CA (United States)

    2012-07-15

    To investigate volumetric and density changes in the ipsilateral and contralateral lobes following volume reduction of an emphysematous target lobe. The study included 289 subjects with heterogeneous emphysema, who underwent bronchoscopic volume reduction of the most diseased lobe with endobronchial valves and 132 untreated controls. Lobar volume and low-attenuation relative area (RA) changes post-procedure were measured from computed tomography images. Regression analysis (Spearman's rho) was performed to test the association between change in the target lobe volume and changes in volume and density variables in the other lobes. The target lobe volume at full inspiration in the treatment group had a mean reduction of -0.45 L (SE = 0.034, P < 0.0001), and was associated with volume increases in the ipsilateral lobe (rho = -0.68, P < 0.0001) and contralateral lung (rho = -0.16, P = 0.006), and overall reductions in expiratory RA (rho = 0.31, P < 0.0001) and residual volume (RV)/total lung capacity (TLC) (rho = 0.13, P = 0.03). When the volume of an emphysematous target lobe is reduced, the volume is redistributed primarily to the ipsilateral lobe, with an overall reduction. Image-based changes in lobar volumes and densities indicate that target lobe volume reduction is associated with statistically significant overall reductions in air trapping, consistent with expansion of the healthier lung. (orig.)

  4. Emphysema lung lobe volume reduction: effects on the ipsilateral and contralateral lobes

    International Nuclear Information System (INIS)

    Brown, Matthew S.; Kim, Hyun J.; Abtin, Fereidoun G.; Galperin-Aizenberg, Maya; Pais, Richard; Da Costa, Irene G.; Ordookhani, Arash; Chong, Daniel; Ni, Chiayi; McNitt-Gray, Michael F.; Goldin, Jonathan G.; Strange, Charlie; Tashkin, Donald P.

    2012-01-01

    To investigate volumetric and density changes in the ipsilateral and contralateral lobes following volume reduction of an emphysematous target lobe. The study included 289 subjects with heterogeneous emphysema, who underwent bronchoscopic volume reduction of the most diseased lobe with endobronchial valves and 132 untreated controls. Lobar volume and low-attenuation relative area (RA) changes post-procedure were measured from computed tomography images. Regression analysis (Spearman's rho) was performed to test the association between change in the target lobe volume and changes in volume and density variables in the other lobes. The target lobe volume at full inspiration in the treatment group had a mean reduction of -0.45 L (SE = 0.034, P < 0.0001), and was associated with volume increases in the ipsilateral lobe (rho = -0.68, P < 0.0001) and contralateral lung (rho = -0.16, P = 0.006), and overall reductions in expiratory RA (rho = 0.31, P < 0.0001) and residual volume (RV)/total lung capacity (TLC) (rho = 0.13, P = 0.03). When the volume of an emphysematous target lobe is reduced, the volume is redistributed primarily to the ipsilateral lobe, with an overall reduction. Image-based changes in lobar volumes and densities indicate that target lobe volume reduction is associated with statistically significant overall reductions in air trapping, consistent with expansion of the healthier lung. (orig.)

  5. Effects of different tidal volumes in pulmonary and extrapulmonary lung injury with or without intraabdominal hypertension.

    Science.gov (United States)

    Santos, Cíntia L; Moraes, Lillian; Santos, Raquel S; Oliveira, Mariana G; Silva, Johnatas D; Maron-Gutierrez, Tatiana; Ornellas, Débora S; Morales, Marcelo M; Capelozzi, Vera L; Jamel, Nelson; Pelosi, Paolo; Rocco, Patricia R M; Garcia, Cristiane S N B

    2012-03-01

    We hypothesized that: (1) intraabdominal hypertension increases pulmonary inflammatory and fibrogenic responses in acute lung injury (ALI); (2) in the presence of intraabdominal hypertension, higher tidal volume reduces lung damage in extrapulmonary ALI, but not in pulmonary ALI. Wistar rats were randomly allocated to receive Escherichia coli lipopolysaccharide intratracheally (pulmonary ALI) or intraperitoneally (extrapulmonary ALI). After 24 h, animals were randomized into subgroups without or with intraabdominal hypertension (15 mmHg) and ventilated with positive end expiratory pressure = 5 cmH(2)O and tidal volume of 6 or 10 ml/kg during 1 h. Lung and chest wall mechanics, arterial blood gases, lung and distal organ histology, and interleukin (IL)-1β, IL-6, caspase-3 and type III procollagen (PCIII) mRNA expressions in lung tissue were analyzed. With intraabdominal hypertension, (1) chest-wall static elastance increased, and PCIII, IL-1β, IL-6, and caspase-3 expressions were more pronounced than in animals with normal intraabdominal pressure in both ALI groups; (2) in extrapulmonary ALI, higher tidal volume was associated with decreased atelectasis, and lower IL-6 and caspase-3 expressions; (3) in pulmonary ALI, higher tidal volume led to higher IL-6 expression; and (4) in pulmonary ALI, liver, kidney, and villi cell apoptosis was increased, but not affected by tidal volume. Intraabdominal hypertension increased inflammation and fibrogenesis in the lung independent of ALI etiology. In extrapulmonary ALI associated with intraabdominal hypertension, higher tidal volume improved lung morphometry with lower inflammation in lung tissue. Conversely, in pulmonary ALI associated with intraabdominal hypertension, higher tidal volume increased IL-6 expression.

  6. Lung and heart dose volume analyses with CT simulator in tangential field irradiation of breast cancer

    International Nuclear Information System (INIS)

    Das, Indra J.; Cheng, Elizabeth C.; Fowble, Barbara

    1997-01-01

    Objective: Radiation pneumonitis and cardiac effects are directly related to the irradiated lung and heart volumes in the treatment fields. The central lung distance (CLD) from a tangential breast radiograph is shown to be a significant indicator of ipsilateral irradiated lung volume based on empirically derived functions which accuracy depends on the actual measured volume in treatment position. A simple and accurate linear relationship with CLD and retrospective analysis of the pattern of dose volume of lung and heart is presented with actual volume data from a CT simulator in the treatment of breast cancer. Materials and Methods: The heart and lung volumes in the tangential treatment fields were analyzed in 45 consecutive (22 left and 23 right breast) patients referred for CT simulation of the cone down treatment. All patients in this study were immobilized and placed on an inclined breast board in actual treatment setup. Both arms were stretched over head uniformly to avoid collision with the scanner aperture. Radiopaque marks were placed on the medial and lateral borders of the tangential fields. All patients were scanned in spiral mode with slice width and thickness of 3 mm each, respectively. The lung and heart structures as well as irradiated areas were delineated on each slice and respective volumes were accurately measured. The treatment beam parameters were recorded and the digitally reconstructed radiographs (DRRs) were generated for the CLD and analysis. Results: Table 1 shows the volume statistics of patients in this study. There is a large variation in the lung and heart volumes among patients. Due to differences in the shape of right and left lungs the percent irradiated volume (PIV) are different. The PIV data have shown to correlate with CLD with 2nd and 3rd degree polynomials; however, in this study a simple straight line regression is used to provide better confidence than the higher order polynomial. The regression lines for the left and right

  7. Converging stereotactic radiotherapy using kilovoltage X-rays: experimental irradiation of normal rabbit lung and dose-volume analysis with Monte Carlo simulation.

    Science.gov (United States)

    Kawase, Takatsugu; Kunieda, Etsuo; Deloar, Hossain M; Tsunoo, Takanori; Seki, Satoshi; Oku, Yohei; Saitoh, Hidetoshi; Saito, Kimiaki; Ogawa, Eileen N; Ishizaka, Akitoshi; Kameyama, Kaori; Kubo, Atsushi

    2009-10-01

    To validate the feasibility of developing a radiotherapy unit with kilovoltage X-rays through actual irradiation of live rabbit lungs, and to explore the practical issues anticipated in future clinical application to humans through Monte Carlo dose simulation. A converging stereotactic irradiation unit was developed, consisting of a modified diagnostic computed tomography (CT) scanner. A tiny cylindrical volume in 13 normal rabbit lungs was individually irradiated with single fractional absorbed doses of 15, 30, 45, and 60 Gy. Observational CT scanning of the whole lung was performed every 2 weeks for 30 weeks after irradiation. After 30 weeks, histopathologic specimens of the lungs were examined. Dose distribution was simulated using the Monte Carlo method, and dose-volume histograms were calculated according to the data. A trial estimation of the effect of respiratory movement on dose distribution was made. A localized hypodense change and subsequent reticular opacity around the planning target volume (PTV) were observed in CT images of rabbit lungs. Dose-volume histograms of the PTVs and organs at risk showed a focused dose distribution to the target and sufficient dose lowering in the organs at risk. Our estimate of the dose distribution, taking respiratory movement into account, revealed dose reduction in the PTV. A converging stereotactic irradiation unit using kilovoltage X-rays was able to generate a focused radiobiologic reaction in rabbit lungs. Dose-volume histogram analysis and estimated sagittal dose distribution, considering respiratory movement, clarified the characteristics of the irradiation received from this type of unit.

  8. Tracking Regional Tissue Volume and Function Change in Lung Using Image Registration

    Directory of Open Access Journals (Sweden)

    Kunlin Cao

    2012-01-01

    Full Text Available We have previously demonstrated the 24-hour redistribution and reabsorption of bronchoalveolar lavage (BAL fluid delivered to the lung during a bronchoscopic procedure in normal volunteers. In this work we utilize image-matching procedures to correlate fluid redistribution and reabsorption to changes in regional lung function. Lung CT datasets from six human subjects were used in this study. Each subject was scanned at four time points before and after BAL procedure. Image registration was performed to align images at different time points and different inflation levels. The resulting dense displacement fields were utilized to track tissue volume changes and reveal deformation patterns of local parenchymal tissue quantitatively. The registration accuracy was assessed by measuring landmark matching errors, which were on the order of 1 mm. The results show that quantitative-assessed fluid volume agreed well with bronchoscopist-reported unretrieved BAL volume in the whole lungs (squared linear correlation coefficient was 0.81. The average difference of lung tissue volume at baseline and after 24 hours was around 2%, which indicates that BAL fluid in the lungs was almost absorbed after 24 hours. Regional lung-function changes correlated with the presence of BAL fluid, and regional function returned to baseline as the fluid was reabsorbed.

  9. Volume-based geometric modeling for radiation transport calculations

    International Nuclear Information System (INIS)

    Li, Z.; Williamson, J.F.

    1992-01-01

    Accurate theoretical characterization of radiation fields is a valuable tool in the design of complex systems, such as linac heads and intracavitary applicators, and for generation of basic dose calculation data that is inaccessible to experimental measurement. Both Monte Carlo and deterministic solutions to such problems require a system for accurately modeling complex 3-D geometries that supports ray tracing, point and segment classification, and 2-D graphical representation. Previous combinatorial approaches to solid modeling, which involve describing complex structures as set-theoretic combinations of simple objects, are limited in their ease of use and place unrealistic constraints on the geometric relations between objects such as excluding common boundaries. A new approach to volume-based solid modeling has been developed which is based upon topologically consistent definitions of boundary, interior, and exterior of a region. From these definitions, FORTRAN union, intersection, and difference routines have been developed that allow involuted and deeply nested structures to be described as set-theoretic combinations of ellipsoids, elliptic cylinders, prisms, cones, and planes that accommodate shared boundaries. Line segments between adjacent intersections on a trajectory are assigned to the appropriate region by a novel sorting algorithm that generalizes upon Siddon's approach. Two 2-D graphic display tools are developed to help the debugging of a given geometric model. In this paper, the mathematical basis of our system is described, it is contrasted to other approaches, and examples are discussed

  10. FOREST STEM VOLUME CALCULATION USING AIRBORNE LIDAR DATA

    Directory of Open Access Journals (Sweden)

    I. Büyüksalih

    2017-05-01

    Full Text Available Airborne LiDAR data have been collected for the city of Istanbul using Riegl laser scanner Q680i with 400 kHz and an average flight height of 600 m. The flight campaign was performed by a helicopter and covers an area of 5400 km2. According to a flight speed of 80 knot a point density of more than 16 points/m2 and a laser footprint size of 30 cm could be achieved. As a result of bundle adjustment, in total, approximately 17,000 LAS files with the file size of 500 m by 700 m have been generated for the whole city. The main object classes Ground, Building, Vegetation (medium, high were derived from these LAS files using the macros in Terrasolid software. The forest area under investigation is located northwest of the city of Istanbul, main tree species occurring in the test site are pine (pinus pinaster, oak (quercus and beech (fagus. In total, 120 LAS tiles covering the investigation area have been analysed using the software IMPACT of Joanneum Research Forschungsgesellschaft, Graz, Austria. First of all, the digital terrain model (DTM and the digital surface models (DSM were imported and converted into a raster file from the original laser point clouds with a spatial resolution of 50 cm. Then, a normalized digital surface model (nDSM was derived as the difference between DSM and the DTM. Tree top detection was performed by multi – resolution filter operations and tree crowns were segmented by a region growing algorithms develop specifically for this purpose. Breast Height Diameter (BHD was calculated on the base of tree height and crown areas derived from image segmentation applying allometric functions found in literature. The assessment of stem volume was then calculated as a function of tree height and BHD. A comparison of timber volume estimated from the LiDAR data and field plots measured by the Forest Department of Istanbul showed R2 of 0.46. The low correlation might arise either from the low quality of the field plots or

  11. Examinations on Applications of Manual Calculation Programs on Lung Cancer Radiation Therapy Using Analytical Anisotropic Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung Min; Kim, Dae Sup; Hong, Dong Ki; Back, Geum Mun; Kwak, Jung Won [Dept. of Radiation Oncology, , Seoul (Korea, Republic of)

    2012-03-15

    There was a problem with using MU verification programs for the reasons that there were errors of MU when using MU verification programs based on Pencil Beam Convolution (PBC) Algorithm with radiation treatment plans around lung using Analytical Anisotropic Algorithm (AAA). On this study, we studied the methods that can verify the calculated treatment plans using AAA. Using Eclipse treatment planning system (Version 8.9, Varian, USA), for each 57 fields of 7 cases of Lung Stereotactic Body Radiation Therapy (SBRT), we have calculated using PBC and AAA with dose calculation algorithm. By developing MU of established plans, we compared and analyzed with MU of manual calculation programs. We have analyzed relationship between errors and 4 variables such as field size, lung path distance of radiation, Tumor path distance of radiation, effective depth that can affect on errors created from PBC algorithm and AAA using commonly used programs. Errors of PBC algorithm have showned 0.2{+-}1.0% and errors of AAA have showned 3.5{+-}2.8%. Moreover, as a result of analyzing 4 variables that can affect on errors, relationship in errors between lung path distance and MU, connection coefficient 0.648 (P=0.000) has been increased and we could calculate MU correction factor that is A.E=L.P 0.00903+0.02048 and as a result of replying for manual calculation program, errors of 3.5{+-}2.8% before the application has been decreased within 0.4{+-}2.0%. On this study, we have learned that errors from manual calculation program have been increased as lung path distance of radiation increases and we could verified MU of AAA with a simple method that is called MU correction factor.

  12. Examinations on Applications of Manual Calculation Programs on Lung Cancer Radiation Therapy Using Analytical Anisotropic Algorithm

    International Nuclear Information System (INIS)

    Kim, Jung Min; Kim, Dae Sup; Hong, Dong Ki; Back, Geum Mun; Kwak, Jung Won

    2012-01-01

    There was a problem with using MU verification programs for the reasons that there were errors of MU when using MU verification programs based on Pencil Beam Convolution (PBC) Algorithm with radiation treatment plans around lung using Analytical Anisotropic Algorithm (AAA). On this study, we studied the methods that can verify the calculated treatment plans using AAA. Using Eclipse treatment planning system (Version 8.9, Varian, USA), for each 57 fields of 7 cases of Lung Stereotactic Body Radiation Therapy (SBRT), we have calculated using PBC and AAA with dose calculation algorithm. By developing MU of established plans, we compared and analyzed with MU of manual calculation programs. We have analyzed relationship between errors and 4 variables such as field size, lung path distance of radiation, Tumor path distance of radiation, effective depth that can affect on errors created from PBC algorithm and AAA using commonly used programs. Errors of PBC algorithm have showned 0.2±1.0% and errors of AAA have showned 3.5±2.8%. Moreover, as a result of analyzing 4 variables that can affect on errors, relationship in errors between lung path distance and MU, connection coefficient 0.648 (P=0.000) has been increased and we could calculate MU correction factor that is A.E=L.P 0.00903+0.02048 and as a result of replying for manual calculation program, errors of 3.5±2.8% before the application has been decreased within 0.4±2.0%. On this study, we have learned that errors from manual calculation program have been increased as lung path distance of radiation increases and we could verified MU of AAA with a simple method that is called MU correction factor.

  13. Pulmonary vascular volume ratio measured by cardiac computed tomography in children and young adults with congenital heart disease: comparison with lung perfusion scintigraphy.

    Science.gov (United States)

    Goo, Hyun Woo; Park, Sang Hyub

    2017-11-01

    Lung perfusion scintigraphy is regarded as the gold standard for evaluating differential lung perfusion ratio in congenital heart disease. To compare cardiac CT with lung perfusion scintigraphy for estimated pulmonary vascular volume ratio in patients with congenital heart disease. We included 52 children and young adults (median age 4 years, range 2 months to 28 years; 31 males) with congenital heart disease who underwent cardiac CT and lung perfusion scintigraphy without an interim surgical or transcatheter intervention and within 1 year. We calculated the right and left pulmonary vascular volumes using threshold-based CT volumetry. Then we compared right pulmonary vascular volume percentages at cardiac CT with right lung perfusion percentages at lung perfusion scintigraphy by using paired t-test and Bland-Altman analysis. The right pulmonary vascular volume percentages at cardiac CT (66.3 ± 14.0%) were significantly smaller than the right lung perfusion percentages at lung perfusion scintigraphy (69.1 ± 15.0%; P=0.001). Bland-Altman analysis showed a mean difference of -2.8 ± 5.8% and 95% limits of agreement (-14.1%, 8.5%) between these two variables. Cardiac CT, in a single examination, can offer pulmonary vascular volume ratio in addition to pulmonary artery anatomy essential for evaluating peripheral pulmonary artery stenosis in patients with congenital heart disease. However there is a wide range of agreement between cardiac CT and lung perfusion scintigraphy.

  14. Characterizing functional lung heterogeneity in COPD using reference equations for CT scan-measured lobar volumes.

    Science.gov (United States)

    Come, Carolyn E; Diaz, Alejandro A; Curran-Everett, Douglas; Muralidhar, Nivedita; Hersh, Craig P; Zach, Jordan A; Schroeder, Joyce; Lynch, David A; Celli, Bartolome; Washko, George R

    2013-06-01

    CT scanning is increasingly used to characterize COPD. Although it is possible to obtain CT scan-measured lung lobe volumes, normal ranges remain unknown. Using COPDGene data, we developed reference equations for lobar volumes at maximal inflation (total lung capacity [TLC]) and relaxed exhalation (approximating functional residual capacity [FRC]). Linear regression was used to develop race-specific (non-Hispanic white [NHW], African American) reference equations for lobar volumes. Covariates included height and sex. Models were developed in a derivation cohort of 469 subjects with normal pulmonary function and validated in 546 similar subjects. These cohorts were combined to produce final prediction equations, which were applied to 2,191 subjects with old GOLD (Global Initiative for Chronic Obstructive Lung Disease) stage II to IV COPD. In the derivation cohort, women had smaller lobar volumes than men. Height positively correlated with lobar volumes. Adjusting for height, NHWs had larger total lung and lobar volumes at TLC than African Americans; at FRC, NHWs only had larger lower lobes. Age and weight had no effect on lobar volumes at TLC but had small effects at FRC. In subjects with COPD at TLC, upper lobes exceeded 100% of predicted values in GOLD II disease; lower lobes were only inflated to this degree in subjects with GOLD IV disease. At FRC, gas trapping was severe irrespective of disease severity and appeared uniform across the lobes. Reference equations for lobar volumes may be useful in assessing regional lung dysfunction and how it changes in response to pharmacologic therapies and surgical or endoscopic lung volume reduction.

  15. Effect of nasal continuous and biphasic positive airway pressure on lung volume in preterm infants

    NARCIS (Netherlands)

    Miedema, Martijn; van der Burg, Pauline S.; Beuger, Sabine; de Jongh, Frans H.; Frerichs, Inez; van Kaam, Anton H.

    2013-01-01

    To monitor regional changes in end-expiratory lung volume (EELV), tidal volumes, and their ventilation distribution during different levels of nasal continuous positive airway pressure (nCPAP) and nasal biphasic positive airway pressure (BiPAP) in stable preterm infants. By using electrical

  16. Visual grading of emphysema severity in candidates for lung volume reduction surgery

    International Nuclear Information System (INIS)

    Cederlund, K.; Bergstrand, L.; Hoegberg, S.; Rasmussen, E.; Svane, B.; Aspelin, P.

    2002-01-01

    Purpose: To investigate which of three types of CT imaging yielded the best results in estimating the degree of emphysema in patients undergoing evaluation for lung volume reduction surgery (LVRS), whether there was any difference in this regard between the cranial and caudal part of the lung, and whether the degree of emphysema had an impact on the estimation. Material and Methods: Four radiologists visually classified different degrees of emphysema on three different types of CT images into four groups. The degree of emphysema was calculated by a computer. The three types of images were as follows: HRCT images (2-mm slice thickness); spiral CT images (10-mm slice thickness); and density-masked images (spiral CT images printed with pixels below 960 HU, depicted in white). Results: The conventionally presented images from HRCT and spiral CT yielded the same results (60% respective 62% correct classifications) in assessing the degree of emphysema irrespective of localisation. Significantly improved results were obtained when the spiral CT images were presented as density-masked images (74%). Conclusion: There was no difference between HRCT and spiral CT in assessing the degree of emphysema in candidates for LVRS. Improvement can be achieved by the use of density-masked images

  17. Monte Carlo calculations of lung dose in ORNL phantom for boron neutron capture therapy

    International Nuclear Information System (INIS)

    Krstic, D.; Markovic, V.M.; Jovanovic, Z.; Milenkovic, B.; Nikezic, D.; Atanackovic, J.

    2014-01-01

    Monte Carlo simulations were performed to evaluate dose for possible treatment of cancers by boron neutron capture therapy (BNCT). The computational model of male Oak Ridge National Laboratory (ORNL) phantom was used to simulate tumours in the lung. Calculations have been performed by means of the MCNP5/X code. In this simulation, two opposite neutron beams were considered, in order to obtain uniform neutron flux distribution inside the lung. The obtained results indicate that the lung cancer could be treated by BNCT under the assumptions of calculations. The difference in evaluated dose in cancer and normal lung tissue suggests that BNCT could be applied for the treatment of cancers. The difference in exposure of cancer and healthy tissue can be observed, so the healthy tissue can be spared from damage. An absorbed dose ratio of metastatic tissue-to-the healthy tissue was ∼5. Absorbed dose to all other organs was low when compared with the lung dose. Absorbed dose depth distribution shows that BNC therapy can be very useful in the treatments for tumour. The ratio of the tumour absorbed dose and irradiated healthy tissue absorbed dose was also ∼5. It was seen that an elliptical neutron field was better irradiation choice. (authors)

  18. Variable tidal volumes improve lung protective ventilation strategies in experimental lung injury.

    Science.gov (United States)

    Spieth, Peter M; Carvalho, Alysson R; Pelosi, Paolo; Hoehn, Catharina; Meissner, Christoph; Kasper, Michael; Hübler, Matthias; von Neindorff, Matthias; Dassow, Constanze; Barrenschee, Martina; Uhlig, Stefan; Koch, Thea; de Abreu, Marcelo Gama

    2009-04-15

    Noisy ventilation with variable Vt may improve respiratory function in acute lung injury. To determine the impact of noisy ventilation on respiratory function and its biological effects on lung parenchyma compared with conventional protective mechanical ventilation strategies. In a porcine surfactant depletion model of lung injury, we randomly combined noisy ventilation with the ARDS Network protocol or the open lung approach (n = 9 per group). Respiratory mechanics, gas exchange, and distribution of pulmonary blood flow were measured at intervals over a 6-hour period. Postmortem, lung tissue was analyzed to determine histological damage, mechanical stress, and inflammation. We found that, at comparable minute ventilation, noisy ventilation (1) improved arterial oxygenation and reduced mean inspiratory peak airway pressure and elastance of the respiratory system compared with the ARDS Network protocol and the open lung approach, (2) redistributed pulmonary blood flow to caudal zones compared with the ARDS Network protocol and to peripheral ones compared with the open lung approach, (3) reduced histological damage in comparison to both protective ventilation strategies, and (4) did not increase lung inflammation or mechanical stress. Noisy ventilation with variable Vt and fixed respiratory frequency improves respiratory function and reduces histological damage compared with standard protective ventilation strategies.

  19. Physiological Modeling of Responses to Upper vs Lower Lobe Lung Volume Reduction in Homogeneous Emphysema

    Directory of Open Access Journals (Sweden)

    Arschang eValipour

    2012-10-01

    Full Text Available Rationale: In clinical trials, homogeneous emphysema patients have responded well to upper lobe volume reduction but not lower lobe volume reduction. Materials/Methods: To understand the physiological basis for this observation, a computer model was developed to simulate the effects of upper and lower lobe lung volume reduction on RV/TLC and lung recoil in homogeneous emphysema.Results: Patients with homogeneous emphysema received either upper or lower lobe volume reduction therapy based on findings of radionucleotide scintigraphy scanning. CT analysis of lobar volumes showed that patients undergoing upper (n=18; -265 mL/site and lower lobe treatment (n=11; -217 mL/site experienced similar reductions in lung volume. However, only upper lobe treatment improved FEV1 (+11.1±14.7% vs -4.4±15.8% and RV/TLC (-5.4± 8.1% vs -2.4±8.6%. Model simulations provided an unexpected explanation for this response. Increases in transpulmonary pressure subsequent to volume reduction increased RV/TLC in upper lobe alveoli, while caudal shifts in airway closure decreased RV/TLC in lower lobe alveoli. Upper lobe treatment, which eliminates apical alveoli with high RV/TLC values, lowers the average RV/TLC of the lung. Conversely, lower lobe treatment, which eliminates caudal alveoli with low RV/TLC values, has less effect. Conclusions: Lower lobe treatment in homogeneous emphysema is uniformly less effective than upper lobe treatment.

  20. Development and proof-of-concept of three-dimensional lung histology volumes

    Science.gov (United States)

    Mathew, Lindsay; Alabousi, Mostafa; Wheatley, Andrew; Aladl, Usaf; Slipetz, Deborah; Hogg, James C.; Fenster, Aaron; Parraga, Grace

    2012-03-01

    Most medical imaging is inherently three-dimensional (3D) but for validation of pathological findings, histopathology is commonly used and typically histopathology images are acquired as twodimensional slices with quantitative analysis performed in a single dimension. Histopathology is invasive, labour-intensive, and the analysis cannot be performed in real time, yet it remains the gold standard for the pathological diagnosis and validation of clinical or radiological diagnoses of disease. A major goal worldwide is to improve medical imaging resolution, sensitivity and specificity to better guide therapy and biopsy and to one day delay or replace biopsy. A key limitation however is the lack of tools to directly compare 3D macroscopic imaging acquired in patients with histopathology findings, typically provided in a single dimension (1D) or in two dimensions (2D). To directly address this, we developed methods for 2D histology slice visualization/registration to generate 3D volumes and quantified tissue components in the 3D volume for direct comparison to volumetric micro-CT and clinical CT. We used the elastase-instilled mouse emphysema lung model to evaluate our methods with murine lungs sectioned (5 μm thickness/10 μm gap) and digitized with 2μm in-plane resolution. 3D volumes were generated for wildtype and elastase mouse lung sections after semi-automated registration of all tissue slices. The 1D mean linear intercept (Lm) for wildtype (WT) (47.1 μm +/- 9.8 μm) and elastase mouse lung (64.5 μm +/- 14.0 μm) was significantly different (p<.001). We also generated 3D measurements based on tissue and airspace morphometry from the 3D volumes and all of these were significantly different (p<.0001) when comparing elastase and WT mouse lung. The ratio of the airspace-to-lung volume for the entire lung volume was also significantly and strongly correlated with Lm.

  1. Target dose study of effects of changes in the AAA calculation resolution on lung SABR plan

    International Nuclear Information System (INIS)

    Kim, Dae Il; Son, Sang Jun; Ahn, Bum Seok; Jung, Chi Hoon; Yoo, Suk Hyun

    2014-01-01

    Changing the calculation grid of AAA in Lung SABR plan and to analyze the changes in target dose, and investigated the effects associated with it, and considered a suitable method of application. 4D CT image that was used to plan all been taken with Brilliance Big Bore CT (Philips, Netherlands) and in Lung SABR plan(Eclipse TM ver10.0.42, Varian, the USA), use anisotropic analytic algorithm(AAA, ver.10, Varian Medical Systems, Palo Alto, CA, USA) and, was calculated by the calculation grid 1.0, 3.0, 5.0 mm in each Lung SABR plan. Lung SABR plan of 10 cases are using each of 1.0 mm, 3.0 mm, 5.0 mm calculation grid, and in case of use a 1.0 mm calculation grid V98 of the prescribed dose is about 99.5%±1.5%, Dmin of the prescribed dose is about 92.5±1.5% and Homogeneity Index(HI) is 1.0489±0.0025. In the case of use a 3.0 mm calculation grid V98 dose of the prescribed dose is about 90±4.5% , Dmin of the prescribed dose is about 87.5±3% and HI is about 1.07±1. In the case of use a 5.0 mm calculation grid V98 dose of the prescribed dose is about 63±15%, Dmin of the prescribed dose is about 83±4% and HI is about 1.13±0.2, respectively. The calculation grid of 1.0 mm is better improves the accuracy of dose calculation than using 3.0 mm and 5.mm, although calculation times increase in the case of smaller PTV relatively. As lung, spread relatively large and low density and small PTV, it is considered and good to use a calculation grid of 1.0 mm

  2. Experimental estimation of regional lung water volume by histogram of pulmonary CT numbers

    International Nuclear Information System (INIS)

    Kato, Shiro; Momoki, Shigeru; Asai, Toshihiko; Shimada, Takeshi; Tamano, Masahiro; Nakamoto, Takaaki; Yoshimura, Masaharu

    1989-01-01

    Both in vitro and in vivo experiments were made to assess the ability of pulmonary CT numbers to quantitatively determine regional water volume in cases of pulmonary congestion or edema associated with left heart failure. In vitro experiment revealed a good linear correlation between the volume of injected water and the determined CT number of polyethylene tube packed with sponge. In the subsequent in vivo experiment with 10 adult mongrel dogs, lung water volumes obtained by pulmonary CT numbers were found to be consistent with the actual volumes. Pulmonary CT numbers for water volume proved to become parameters to quantitatively evaluate pulmonary congestion or edema. (Namekawa, K)

  3. Optimization of extracranial stereotactic radiation therapy of small lung lesions using accurate dose calculation algorithms

    International Nuclear Information System (INIS)

    Dobler, Barbara; Walter, Cornelia; Knopf, Antje; Fabri, Daniella; Loeschel, Rainer; Polednik, Martin; Schneider, Frank; Wenz, Frederik; Lohr, Frank

    2006-01-01

    The aim of this study was to compare and to validate different dose calculation algorithms for the use in radiation therapy of small lung lesions and to optimize the treatment planning using accurate dose calculation algorithms. A 9-field conformal treatment plan was generated on an inhomogeneous phantom with lung mimics and a soft tissue equivalent insert, mimicking a lung tumor. The dose distribution was calculated with the Pencil Beam and Collapsed Cone algorithms implemented in Masterplan (Nucletron) and the Monte Carlo system XVMC and validated using Gafchromic EBT films. Differences in dose distribution were evaluated. The plans were then optimized by adding segments to the outer shell of the target in order to increase the dose near the interface to the lung. The Pencil Beam algorithm overestimated the dose by up to 15% compared to the measurements. Collapsed Cone and Monte Carlo predicted the dose more accurately with a maximum difference of -8% and -3% respectively compared to the film. Plan optimization by adding small segments to the peripheral parts of the target, creating a 2-step fluence modulation, allowed to increase target coverage and homogeneity as compared to the uncorrected 9 field plan. The use of forward 2-step fluence modulation in radiotherapy of small lung lesions allows the improvement of tumor coverage and dose homogeneity as compared to non-modulated treatment plans and may thus help to increase the local tumor control probability. While the Collapsed Cone algorithm is closer to measurements than the Pencil Beam algorithm, both algorithms are limited at tissue/lung interfaces, leaving Monte-Carlo the most accurate algorithm for dose prediction

  4. Mediastinal staging for lung cancer: the influence of biopsy volume

    DEFF Research Database (Denmark)

    Nelson, Elof; Pape, Christian; Jørgensen, Ole Dan

    2010-01-01

    OBJECTIVE: Mediastinal staging is of paramount importance prior to surgery for non-small-cell lung cancer (NSCLC) to identify patients with N2-disease. Mediastinoscopy remains the gold standard, and sampling from at least three lymph node stations is generally recommended. It is unknown whether...

  5. The effect of different lung densities on the accuracy of various radiotherapy dose calculation methods: implications for tumour coverage

    DEFF Research Database (Denmark)

    Aarup, Lasse Rye; Nahum, Alan E; Zacharatou, Christina

    2009-01-01

    PURPOSE: To evaluate against Monte-Carlo the performance of various dose calculations algorithms regarding lung tumour coverage in stereotactic body radiotherapy (SBRT) conditions. MATERIALS AND METHODS: Dose distributions in virtual lung phantoms have been calculated using four commercial Treatm...... target dose, the AAA(Ecl) and CCC(OMP) algorithms appear to be adequate alternatives to MC....

  6. Effectiveness and efficacy of minimally invasive lung volume reduction surgery for emphysema.

    Science.gov (United States)

    Pertl, Daniela; Eisenmann, Alexander; Holzer, Ulrike; Renner, Anna-Theresa; Valipour, A

    2014-01-01

    Lung emphysema is a chronic, progressive and irreversible destruction of the lung tissue. Besides non-medical therapies and the well established medical treatment there are surgical and minimally invasive methods for lung volume reduction (LVR) to treat severe emphysema. This report deals with the effectiveness and cost-effectiveness of minimally invasive methods compared to other treatments for LVR in patients with lung emphysema. Furthermore, legal and ethical aspects are discussed. No clear benefit of minimally invasive methods compared to surgical methods can be demonstrated based on the identified and included evidence. In order to assess the different methods for LVR regarding their relative effectiveness and safety in patients with lung emphysema direct comparative studies are necessary.

  7. Effectiveness and efficacy of minimally invasive lung volume reduction surgery for emphysema

    Directory of Open Access Journals (Sweden)

    Pertl, Daniela

    2014-10-01

    Full Text Available [english] Lung emphysema is a chronic, progressive and irreversible destruction of the lung tissue. Besides non-medical therapies and the well established medical treatment there are surgical and minimally invasive methods for lung volume reduction (LVR to treat severe emphysema. This report deals with the effectiveness and cost-effectiveness of minimally invasive methods compared to other treatments for LVR in patients with lung emphysema. Furthermore, legal and ethical aspects are discussed. No clear benefit of minimally invasive methods compared to surgical methods can be demonstrated based on the identified and included evidence. In order to assess the different methods for LVR regarding their relative effectiveness and safety in patients with lung emphysema direct comparative studies are necessary.

  8. Whole-lung volume and density in spirometrically-gated inspiratory and expiratory CT in systemic sclerosis: correlation with static volumes at pulmonary function tests.

    Science.gov (United States)

    Camiciottoli, G; Diciotti, S; Bartolucci, M; Orlandi, I; Bigazzi, F; Matucci-Cerinic, M; Pistolesi, M; Mascalchi, M

    2013-03-01

    Spiral low-dose computed tomography (LDCT) permits to measure whole-lung volume and density in a single breath-hold. To evaluate the agreement between static lung volumes measured with LDCT and pulmonary function test (PFT) and the correlation between the LDCT volumes and lung density in restrictive lung disease. Patients with Systemic Sclerosis (SSc) with (n = 24) and without (n = 16) pulmonary involvement on sequential thin-section CT and patients with chronic obstructive pulmonary disease (COPD)(n = 29) underwent spirometrically-gated LDCT at 90% and 10% of vital capacity to measure inspiratory and expiratory lung volumes and mean lung attenuation (MLA). Total lung capacity and residual volume were measured the same day of CT. Inspiratory [95% limits of agreement (95% LoA)--43.8% and 39.2%] and expiratory (95% LoA -45.8% and 37.1%) lung volumes measured on LDCT and PFT showed poor agreement in SSc patients with pulmonary involvement, whereas they were in substantial agreement (inspiratory 95% LoA -14.1% and 16.1%; expiratory 95% LoA -13.5% and 23%) in SSc patients without pulmonary involvement and in inspiratory scans only (95% LoA -23.1% and 20.9%) of COPD patients. Inspiratory and expiratory LDCT volumes, MLA and their deltas differentiated both SSc patients with or without pulmonary involvement from COPD patients. LDCT lung volumes and density were not correlated in SSc patients with pulmonary involvement, whereas they did correlate in SSc without pulmonary involvement and in COPD patients. In restrictive lung disease due to SSc there is poor agreement between static lung volumes measured using LDCT and PFT and the relationship between volume and density values on CT is altered.

  9. Decreasing Irradiated Rat Lung Volume Changes Dose-Limiting Toxicity From Early to Late Effects

    Energy Technology Data Exchange (ETDEWEB)

    Veen, Sonja J. van der; Faber, Hette; Ghobadi, Ghazaleh [Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Brandenburg, Sytze [KVI Center for Advanced Radiation Research, University of Groningen, Groningen (Netherlands); Langendijk, Johannes A. [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Coppes, Robert P. [Department of Cell Biology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands); Luijk, Peter van, E-mail: p.van.luijk@umcg.nl [Department of Radiation Oncology, University of Groningen, University Medical Center Groningen, Groningen (Netherlands)

    2016-01-01

    Purpose: Technological developments in radiation therapy result in smaller irradiated volumes of normal tissue. Because the risk of radiation therapy-induced toxicity generally depends on irradiated volume, changing volume could change the dose-limiting toxicity of a treatment. Recently, in our rat model, we found that early radiation-induced lung dysfunction (RILD) was closely related to irradiated volume dependent vascular remodeling besides inflammation. The exact relationship between early and late RILD is still unknown. Therefore, in this preclinical study we investigated the dose-volume relationship of late RILD, assessed its dependence on early and late pathologies and studied if decreasing irradiated volume changed the dose-limiting toxicity. Methods and Materials: A volume of 25%, 32%, 50%, 63%, 88%, or 100% of the rat lung was irradiated using protons. Until 26 weeks after irradiation, respiratory rates were measured. Macrovascular remodeling, pulmonary inflammation, and fibrosis were assessed at 26 weeks after irradiation. For all endpoints dose-volume response curves were made. These results were compared to our previously published early lung effects. Results: Early vascular remodeling and inflammation correlated significantly with early RILD. Late RILD correlated with inflammation and fibrosis, but not with vascular remodeling. In contrast to the early effects, late vascular remodeling, inflammation and fibrosis showed a primarily dose but not volume dependence. Comparison of respiratory rate increases early and late after irradiation for the different dose-distributions indicated that with decreasing irradiated volumes, the dose-limiting toxicity changed from early to late RILD. Conclusions: In our rat model, different pathologies underlie early and late RILD with different dose-volume dependencies. Consequently, the dose-limiting toxicity changed from early to late dysfunction when the irradiated volume was reduced. In patients, early and late

  10. The role of three dimensional functional lung imaging in radiation treatment planning: the functional dose-volume histogram

    International Nuclear Information System (INIS)

    Marks, Lawrence B.; Spencer, David P.; Sherouse, George W.; Bentel, Gunilla; Clough, Robert; Vann, Karen; Jaszczak, Ronald; Coleman, R. Edward; Prosnitz, Leonard R.

    1995-01-01

    Purpose: During thoracic irradiation (XRT), treatment fields are usually designed to minimize the volume of nontumor-containing lung included. Generally, functional heterogeneities within the lung are not considered. The three dimensional (3D) functional information provided by single photon emission computed tomography (SPECT) lung perfusion scans might be useful in designing beams that minimize incidental irradiation of functioning lung tissue. We herein review the pretreatment SPECT scans in 86 patients (56 with lung cancer) to determine which are likely to benefit from this technology. Methods and Materials: Prior to thoracic XRT, SPECT lung perfusion scans were obtained following the intravenous injection of ∼4 mCi of 99m Tc-labeled macro-aggregated albumin. The presence of areas of decreased perfusion, their location relative to the tumor, and the potential clinical usefulness of their recognition, were scored. Patients were grouped and compared (two-tailed chi-square) based on clinical factors. Conventional dose-volume histograms (DVHs) and functional DVHs (DV F Hs) are calculated based on the dose distribution throughout the computed tomography (CT)-defined lung and SPECT-defined perfused lung, respectively. Results: Among 56 lung cancer patients, decreases in perfusion were observed at the tumor, adjacent to the tumor, and separate from the tumor in 94%, 74%, and 42% of patients, respectively. Perfusion defects adjacent to the tumor were often large with centrally placed tumors. Hypoperfusion in regions separate from the tumor were statistically most common in patients with relatively poor pulmonary function and chronic obstructive pulmonary disease (COPD). Considering all SPECT defects adjacent to and separate from the tumor, corresponding CT abnormalities were seen in only ∼50% and 20% of patients, respectively, and were generally not as impressive. Following XRT, hypoperfusion at and separate from the tumor persisted, while defects adjacent to the

  11. Does the IMRT technique allow improvement of treatment plans (e.g. lung sparing) for lung cancer patients with small lung volume: a planning study

    International Nuclear Information System (INIS)

    Komosinska, K.; Kepka, L.; Gizynska, M.; Zawadzka, A.

    2008-01-01

    Aim: We evaluated whether intensity-modulated radiation therapy (IMRT) may offer any advantages in comparison with three-dimensional conformal radiotherapy (3D-CRT) for patients with small lung volume (SLV). Methods: Treatment planning was performed for 10 NSCLC patients with the smallest lung volume (mean: 2241 cc) among 200 patients from our database. For each patient 3D-CRT and IMRT plans were prepared. The goal was to deliver 66 Gy/33 fractions, with dose constraints: mean lung dose (MLD) < 20 Gy, V20 < 35%; spinal cord - Dmax < 45 Gy. When the plan could not meet these criteria, total dose was reduced. The 3D-CRT and IMRT plans were compared. We investigated: prescribed dose, coverage and conformity indices, MLD, V5-V65 in the lung. Results: In 4 out of 10 plans, 3D-CRT did not allow 66 Gy to be delivered, because of predicted pulmonary toxicity. These 4 cases included 3 for which we did not reach 66 Gy with IMRT; still, for these 3 plans the total dose was increased by an average of 9 Gy with IMRT in comparison with 3D-CRT. Coverage indices were similar for both techniques. Conformity indices were better for IMRT plans. MLD was lower in five IMRT and two 3D-CRT plans if equal doses were delivered. The decrease in MLD was seen for cases with large PTV and high PTV/lung volume ratio. Lung V5 was lower for all 3D-CRT plans, 47% vs. 57% for IMRT; V15 and above were larger for 3D-CRT Conclusion: In the planning study, IMRT seems to be a promising technique for cases with SLV, especially when associated with large PT V. (authors)

  12. Lung density

    DEFF Research Database (Denmark)

    Garnett, E S; Webber, C E; Coates, G

    1977-01-01

    The density of a defined volume of the human lung can be measured in vivo by a new noninvasive technique. A beam of gamma-rays is directed at the lung and, by measuring the scattered gamma-rays, lung density is calculated. The density in the lower lobe of the right lung in normal man during quiet...... breathing in the sitting position ranged from 0.25 to 0.37 g.cm-3. Subnormal values were found in patients with emphsema. In patients with pulmonary congestion and edema, lung density values ranged from 0.33 to 0.93 g.cm-3. The lung density measurement correlated well with the findings in chest radiographs...... but the lung density values were more sensitive indices. This was particularly evident in serial observations of individual patients....

  13. Combining "open-lung" ventilation and arteriovenous extracorporeal lung assist: influence of different tidal volumes on gas exchange in experimental lung failure.

    Science.gov (United States)

    Muellenbach, Ralf M; Kredel, Markus; Kuestermann, Julian; Klingelhoefer, Michael; Schuster, Frank; Wunder, Christian; Kranke, Peter; Roewer, Norbert; Brederlau, Jörg

    2009-08-01

    Although low-tidal ventilation may reduce mortality in acute respiratory distress syndrome (ARDS), it can also result in severe respiratory acidosis and lung derecruitment. This study tested the hypothesis that combining "open-lung" ventilation and arteriovenous extracorporeal lung assist (av-ECLA) allows for maximal tidal volume (VT) reduction without the development of decompensated respiratory acidosis and impairment of oxygenation. After induction of ARDS in eight female pigs (56.1+/-3.2 kg), lung recruitment was performed and positive end-expiratory pressure was set 3 cmH2O above the lower inflection point of the pressure-volume curve. All animals were ventilated in the pressure-controlled ventilation mode (PCV) with VTs ranging from 0-8 ml/kg. At each VT, gas exchange and hemodynamic measurements were obtained with the av-ECLA circuit clamped and declamped. With each declamping, the gas flow through the membrane lung was set to 10 l of oxygen/min. The respiratory rate was adjusted to maintain normocapnia, but limited to 40/min. After lung recruitment, oxygenation remained significantly improved although VTs were minimized to 0 ml/kg (p<0.05). PaO2 was significantly improved during PCV and av-ECLA compared with PCV alone at VTs <4 ml/kg (p<0.05). With VT <6 ml/kg, severe acidosis could only be avoided if PCV was combined with av-ECLA. Due to sufficient CO2 elimination during av-ECLA, the VTs could be reduced to 0-2 ml/kg without the risk of decompensated respiratory acidosis. It was also shown that the "open-lung" strategy chosen was associated with sustained improvements in oxygenation, even though VTs were minimized.

  14. Relationship between dose-volume parameters and pulmonary complications after neoadjuvant chemoradiotherapy followed by surgery for lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Shigeo; Shibata, Toru [Kagawa University Hospital, Department of Radiation Oncology, Kagawa (Japan); Go, Tetsuhiko; Kasai, Yoshitaka; Yokomise, Hiroyasu [Kagawa University, Department of General Thoracic, Breast and Endocrine Surgery, Faculty of Medicine, Kagawa (Japan)

    2016-09-15

    This study evaluated the relationship between dose-volume histogram (DVH) parameters and pulmonary complications after neoadjuvant chemoradiotherapy (NACRT) followed by surgery for lung cancer. We also examined a new DVH parameter, because the unresected lung should be more spared than the later resected lung. Data from 43 non-small cell lung cancer patients were retrospectively analyzed. The DVH parameters of the lung were calculated from the total bilateral lung volume minus (1) the gross tumor volume (DVHg) or (2) the later resected lung volume (DVHr). Radiation pneumonitis (RP) and fistula, including bronchopleural and pulmonary fistula, were graded as the pulmonary complications. Factors affecting the incidences of grade 2 or higher RP (≥G2 RP) and fistula were analyzed. Sixteen patients (37 %) experienced ≥G2 RP and a V20 value of the total lung minus the later resected lung (V20r) ≥ 12 % was a significant factor affecting the incidence of ≥G2 RP (p = 0.032). Six patients (14 %) developed a fistula and a V35 value of the total lung minus the gross tumor (V35g) ≥ 19 % and a V40g ≥ 16 % were significant factors affecting the incidence of fistula (p = 0.002 and 0.009, respectively). These DVH parameters may be related to the incidences of ≥G2 RP and fistula. (orig.) [German] In dieser Studie wurde die Beziehung zwischen Dosis-Volumen-Histogramm-(DVH-)Parametern und pulmonalen Komplikationen nach neoadjuvanter Radiochemotherapie (NARCT) und nachfolgender Operation beim Lungenkarzinom untersucht. Zudem wurde ein neuer DVH-Parameter untersucht, da das nichtresezierte Lungengewebe mehr geschont werden sollte als reseziertes Gewebe. Daten von 43 Patienten mit nicht-kleinzelligem Bronchialkarzinom wurden retrospektiv analysiert. Die DVH-Parameter der Lunge wurden aus dem gesamten beidseitigen Lungenvolumen minus (1) das makroskopische Tumorvolumen (DVHg) oder (2) das resezierte Lungenvolumen (DVHr) ermittelt. Strahlenpneumonitis (RP) und Fisteln

  15. The Effects of Hemodynamic Alterations on Lung Volumes in Fetuses with Tetralogy of Fallot: An MRI Study.

    Science.gov (United States)

    Berger-Kulemann, Vanessa; Berger, Rudolf; Mlczoch, Elisabeth; Sternal, Daniel; Mailath-Pokorny, Mariella; Hachemian, Nilouparak; Prayer, Daniela; Weber, Michael; Salzer-Muhar, Ulrike

    2015-08-01

    This study assessed whether the presence of tetralogy of Fallot (TOF) affects fetal lung development and whether these fetuses are at risk of pulmonary hypoplasia (PH). Furthermore, we investigated whether the degree of the concomitant pulmonary valve (PV) stenosis or a stenosis in the branch pulmonary arteries correlates with the fetal lung volume. Lung volumetry was performed in 16 fetuses with TOF who underwent MRI between gestational weeks 21 and 35 and in 22 controls. Fetal biometric data and the diameters of the PVs were evaluated by ultrasound. PV and branch pulmonary artery diameters were standardized (z-scores), and fetal lung volume/fetal body weight (FLV/FBW) ratios (ml/g) were calculated. The mean FLV/FBW ratio (0.031 ± 0.009 ml/g) in the TOF group was statistically significantly lower than in the control group (0.041 ± 0.009 ml/g; P = 0.003). None of the fetuses with TOF met the criterion for PH. FLV did not correlate with the degree of PV stenosis, but rather with the presence of a significant stenosis in at least one branch pulmonary artery. The presence of TOF moderately affects fetal lung growth, which is apparently not dependent on the degree of the PV stenosis. However, only an additional stenosis in at least one branch pulmonary artery was associated with a small FLV, but not with PH. Thus, reduced pulmonary blood flow may be offset by additional factors, such as the ability to establish a sufficient collateral system and to alter structural vascular size and, thus, pulmonary vascular resistance.

  16. Target volume determination in radiotherapy for non-small-cell lung cancer-facts and questions

    International Nuclear Information System (INIS)

    Kepka, L.; Bujko, K.

    2003-01-01

    Although the precise target volume definition in conformal radiotherapy is required by ICRU Report 50 and 62, this task in radiotherapy for non-small-cell lung cancer (NSCLC) is often controversial and strict accordance with ICRU requirements is hard to achieve. The Gross Tumour Volume (GTV) definition depends mainly on the imaging method used. We discuss the use of new imaging modalities, like PET, in GTV definition. The Clinical Target Volume (CTV) definition remains a separate, and still unresolved problem, especially in the part concerning the Elective Nodal Irradiation (ENI). Nowadays, there is no unified attitude among radiation oncologists regarding the necessity and extent of ENI. The common use of combined treatment modalities and the tendency to dose escalation, both increasing the potential toxicity, result in the more frequent use of involved-fields techniques. Problems relating to margins during Planning Target Volume (PTV) of lung cancer irradiation are also discussed. Another issue is the Interclinician variability in target volumes definition, especially when there is data indicating that the GTV, as defined by 3 D-treatment planning in NSCLC radiotherapy, may be highly prognostic for survival. We postulate that special attention should be paid to detailed precision of target volume determination in departmental and trial protocols. Careful analysis of patterns of failures from ongoing protocols will enable us to formulate the guidelines for target volume definition in radiotherapy for lung cancer. (author)

  17. The relationships between tracheal index and lung volume parameters in mild-to-moderate COPD

    Energy Technology Data Exchange (ETDEWEB)

    Eom, Jung Seop, E-mail: ejs00@hanmail.net [Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710 (Korea, Republic of); Lee, Geewon, E-mail: rabkingdom@naver.com [Department of Radiology, Pusan National University Hospital, 179 Gudeok-ro, Seo-gu, Busan 602-739 (Korea, Republic of); Lee, Ho Yun, E-mail: hoyunlee96@gmail.com [Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710 (Korea, Republic of); Oh, Jin Young, E-mail: indr71@hanmail.net [Division of Pulmonology, Department of Internal Medicine, Dongguk University Ilsan Medical Center, 814 Siksa-dong, Ilsandong-gu, Goyang-si, Gyeonggi-do 410-773 (Korea, Republic of); Woo, Sook-young, E-mail: sookyoung12.woo@samsung.com [Biostatistics Team, Samsung Biomedical Research Institute, 81 Irwon-ro, Gangnam-gu, Seoul 135-710 (Korea, Republic of); Jeon, Kyeongman, E-mail: kjeon@skku.edu [Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710 (Korea, Republic of); Um, Sang-Won, E-mail: sangwonum@skku.edu [Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710 (Korea, Republic of); Koh, Won-Jung, E-mail: wjkoh@skku.edu [Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710 (Korea, Republic of); Suh, Gee Young, E-mail: suhgy@skku.edu [Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710 (Korea, Republic of); and others

    2013-12-01

    Background: Although elongated morphological changes in the trachea are known to be related to lung function in chronic obstructive pulmonary disease (COPD), whether the tracheal morphological changes are associated with airflow limitations or overinflation of the lung in the early stages of COPD has not yet been determined. Thus, our aim was to investigate the association of tracheal index (TI) with lung function parameters, including lung volume parameters, in COPD patients with mild-to-moderate airflow limitations. Materials and methods: A retrospective study was conducted in 193 COPD patients with GOLD grades 1–2 (post-bronchodilator forced expiratory volume in 1 s [FEV{sub 1}] ≥ 50% predicted with FEV{sub 1}/forced vital capacity ratio ≤ 70%; age range, 40–81) and 193 age- and gender-matched subjects with normal lung function as a control group (age range, 40–82). Two independent observers measured TI at three anatomical levels on chest radiographs and CT scans. Results: Compared with the control group, TI was reduced significantly and “saber-sheath trachea” was observed more frequently in COPD patients. Patients with GOLD grade 2 disease had a lower TI than those with GOLD grade 1. TI had apparent inverse correlations with total lung capacity, functional residual capacity, and residual volume, regardless of the anatomical level of the trachea. Even after adjustments for covariates, this association persisted. Conclusions: TI is reduced even in mild-to-moderate COPD patients, and TI measured on chest CT shows significant inverse relationships with all lung volume parameters assessed, suggesting that tracheal morphology may change during the early stages of COPD.

  18. The relationships between tracheal index and lung volume parameters in mild-to-moderate COPD

    International Nuclear Information System (INIS)

    Eom, Jung Seop; Lee, Geewon; Lee, Ho Yun; Oh, Jin Young; Woo, Sook-young; Jeon, Kyeongman; Um, Sang-Won; Koh, Won-Jung; Suh, Gee Young

    2013-01-01

    Background: Although elongated morphological changes in the trachea are known to be related to lung function in chronic obstructive pulmonary disease (COPD), whether the tracheal morphological changes are associated with airflow limitations or overinflation of the lung in the early stages of COPD has not yet been determined. Thus, our aim was to investigate the association of tracheal index (TI) with lung function parameters, including lung volume parameters, in COPD patients with mild-to-moderate airflow limitations. Materials and methods: A retrospective study was conducted in 193 COPD patients with GOLD grades 1–2 (post-bronchodilator forced expiratory volume in 1 s [FEV 1 ] ≥ 50% predicted with FEV 1 /forced vital capacity ratio ≤ 70%; age range, 40–81) and 193 age- and gender-matched subjects with normal lung function as a control group (age range, 40–82). Two independent observers measured TI at three anatomical levels on chest radiographs and CT scans. Results: Compared with the control group, TI was reduced significantly and “saber-sheath trachea” was observed more frequently in COPD patients. Patients with GOLD grade 2 disease had a lower TI than those with GOLD grade 1. TI had apparent inverse correlations with total lung capacity, functional residual capacity, and residual volume, regardless of the anatomical level of the trachea. Even after adjustments for covariates, this association persisted. Conclusions: TI is reduced even in mild-to-moderate COPD patients, and TI measured on chest CT shows significant inverse relationships with all lung volume parameters assessed, suggesting that tracheal morphology may change during the early stages of COPD

  19. Mechanical ventilation with lower tidal volumes and positive end-expiratory pressure prevents alveolar coagulation in patients without lung injury

    NARCIS (Netherlands)

    Choi, Goda; Wolthuis, Esther K.; Bresser, Paul; Levi, Marcel; van der Poll, Tom; Dzoljic, Misa; Vroom, Margreeth B.; Schultz, Marcus J.

    2006-01-01

    BACKGROUND: Alveolar fibrin deposition is a hallmark of acute lung injury, resulting from activation of coagulation and inhibition of fibrinolysis. Previous studies have shown that mechanical ventilation with high tidal volumes may aggravate lung injury in patients with sepsis and acute lung injury.

  20. Co-registered perfusion SPECT/CT: Utility for prediction of improved postoperative outcome in lung volume reduction surgery candidates

    International Nuclear Information System (INIS)

    Takenaka, Daisuke; Ohno, Yoshiharu; Koyama, Hisanobu; Nogami, Munenobu; Onishi, Yumiko; Matsumoto, Keiko; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Sugimura, Kazuro

    2010-01-01

    Purpose: To directly compare the capabilities of perfusion scan, SPECT, co-registered SPECT/CT, and quantitatively and qualitatively assessed MDCT (i.e. quantitative CT and qualitative CT) for predicting postoperative clinical outcome for lung volume reduction surgery (LVRS) candidates. Materials and methods: Twenty-five consecutive candidates (19 men and six women, age range: 42-72 years) for LVRS underwent preoperative CT and perfusion scan with SPECT. Clinical outcome of LVRS for all subjects was also assessed by determining the difference between pre- and postoperative forced expiratory volume in 1 s (FEV 1 ) and 6-min walking distance (6MWD). All SPECT examinations were performed on a SPECT scanner, and co-registered to thin-section CT by using commercially available software. On planar imaging, SPECT and SPECT/CT, upper versus lower zone or lobe ratios (U/Ls) were calculated from regional uptakes between upper and lower lung fields in the operated lung. On quantitatively assessed CT, U/L for all subjects was assessed from regional functional lung volumes. On qualitatively assessed CT, planar imaging, SPECT and co-registered SPECT/CT, U/Ls were assessed with a 4-point visual scoring system. To compare capabilities of predicting clinical outcome, each U/L was statistically correlated with the corresponding clinical outcome. Results: Significantly fair or moderate correlations were observed between quantitatively and qualitatively assessed U/Ls obtained with all four methods and clinical outcomes (-0.60 ≤ r ≤ -0.42, p < 0.05). Conclusion: Co-registered perfusion SPECT/CT has better correlation with clinical outcome in LVRS candidates than do planar imaging, SPECT or qualitatively assessed CT, and is at least as valid as quantitatively assessed CT.

  1. Co-registered perfusion SPECT/CT: Utility for prediction of improved postoperative outcome in lung volume reduction surgery candidates

    Energy Technology Data Exchange (ETDEWEB)

    Takenaka, Daisuke [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan); Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.j [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan); Koyama, Hisanobu [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan); Nogami, Munenobu [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan); Division of Image-Based Medicine, Institute of Biomedical Research and Innovation, 2-2, Minatojima Minamimachi Chuo-ku, Kobe, Hyogo, 650-0047 (Japan); Onishi, Yumiko [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan); Matsumoto, Keiko [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan); Department of Radiology, University of Yamanashi, 1110 Shimogato, Chuo, Yamanashi, 409-3898 (Japan); Yoshikawa, Takeshi; Matsumoto, Sumiaki; Sugimura, Kazuro [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017 (Japan)

    2010-06-15

    Purpose: To directly compare the capabilities of perfusion scan, SPECT, co-registered SPECT/CT, and quantitatively and qualitatively assessed MDCT (i.e. quantitative CT and qualitative CT) for predicting postoperative clinical outcome for lung volume reduction surgery (LVRS) candidates. Materials and methods: Twenty-five consecutive candidates (19 men and six women, age range: 42-72 years) for LVRS underwent preoperative CT and perfusion scan with SPECT. Clinical outcome of LVRS for all subjects was also assessed by determining the difference between pre- and postoperative forced expiratory volume in 1 s (FEV{sub 1}) and 6-min walking distance (6MWD). All SPECT examinations were performed on a SPECT scanner, and co-registered to thin-section CT by using commercially available software. On planar imaging, SPECT and SPECT/CT, upper versus lower zone or lobe ratios (U/Ls) were calculated from regional uptakes between upper and lower lung fields in the operated lung. On quantitatively assessed CT, U/L for all subjects was assessed from regional functional lung volumes. On qualitatively assessed CT, planar imaging, SPECT and co-registered SPECT/CT, U/Ls were assessed with a 4-point visual scoring system. To compare capabilities of predicting clinical outcome, each U/L was statistically correlated with the corresponding clinical outcome. Results: Significantly fair or moderate correlations were observed between quantitatively and qualitatively assessed U/Ls obtained with all four methods and clinical outcomes (-0.60 {<=} r {<=} -0.42, p < 0.05). Conclusion: Co-registered perfusion SPECT/CT has better correlation with clinical outcome in LVRS candidates than do planar imaging, SPECT or qualitatively assessed CT, and is at least as valid as quantitatively assessed CT.

  2. Lung volumes and maximal respiratory pressures in collegiate swimmers and runners.

    Science.gov (United States)

    Cordain, L; Tucker, A; Moon, D; Stager, J M

    1990-03-01

    To determine whether respiratory muscle strength is related to pulmonary volume differences in athletes and nonathletes, 11 intercollegiate female swimmers, 11 female cross-country runners, and two nonathletic control groups, matched to the athletes in height and age, were evaluated for pulmonary parameters including maximal inspiratory pressure (PImax) and maximal expiratory pressure (PEmax). Swimmers exhibited larger (p less than .05) vital capacities (VC), residual lung volumes (RV), inspiratory capacities (IC), and functional residual capacities (FRC) than both the runners or the controls but no difference (p greater than .05) in either PImax or inspiratory flow (FIV 25%-75%). Timed expiratory volumes (FEV 0.5 and FEV 1.0) were significantly (p less than .05) lower in the swimmers than in the controls. These data suggest that an adaptational growth may be responsible, in part, for the augmented static lung volumes demonstrated in swimmers.

  3. SU-E-J-75: Importance of 4DCT for Target Volume Definition in Stereotactic Lung Radiotherapy

    International Nuclear Information System (INIS)

    Goksel, E; Cone, D; Kucucuk, H; Senkesen, O; Yilmaz, M; Aslay, I; Tezcanli, E; Garipagaoglu, M; Sengoz, M

    2014-01-01

    Purpose: We aimed to investigate the importance of 4DCT for lung tumors treated with SBRT and whether maximum intensity projection (MIP) and free breathing (FB) images can compansate for tumor movement. Methods: Six patients with primary lung cancer and 2 patients with lung metastasis with a median age of 69.5 (42–86) were included. Patients were positioned supine on a vacuum bag. In addition to FB planning CT images, 4DCT images were obtained at 3 mm intervals using Varian RPM system with (Siemens Somatom Sensetion 64). MIP series were reconstructed using 4DCT images. PTV-FB and PTV-MIP (GTV+5mm) volumes were contoured using FB and MIP series, respectively. GTVs were defined on each of eight different breathing phase images and were merged to create the ITV. PTV-4D was generated with a 5 mm margin to ITV. PTV-MIP and PTV-4D contours were copied to FB CT series and treatment plans for PTV-MIP and PTV-FB were generated using RapidArc (2 partial arc) technique in Eclipse (version 11, AAA algorithm). The prescription dose was 5600cGy in 7 fractions. ITV volumes receiving prescription dose (%) and V95 for ITV were calculated for each treatment plan. Results: The mean PTV-4B, PTV-MIP and PTV-FB volumes were 23.2 cc, 15.4cc ve 11cc respectively. Median volume of ITV receiving the prescription dose was 34.6% (16.4–70 %) and median V95 dose for ITV was 1699cGy (232cGy-5117cGy) in the plan optimized for PTV-FB as the reference. When the plan was optimized for PTV-MIP, median ITV volume receiving the prescription dose was 67.15% (26–86%) and median V95 dose for ITV was 4231cGy (1735cGy-5290cGy). Conclusion: Images used in lung SBRT are critical for treatment quality; FB and MIP images did not compensate target movement, therefore 4DCT images should be obtained for all patients undergoing lung SBRT or the safety margins should be adjusted

  4. Calculation of lung-heart ratios for single-photon emission computed tomography

    International Nuclear Information System (INIS)

    Soares, E.J.; King, M.A.; Glick, S.J.; Villegas, B.J.

    1996-01-01

    The authors investigate the effectiveness of simple iterative reconstruction techniques in calculating lung-heart activity ratios (LHRs). The LHR has been shown to be an effective indicator of the severity of coronary artery disease in cardiac SPECT. A study was conducted with a mathematical cardiac torso phantom that modelled uptake of 201 Tl in the heart and lung regions. The projection data included only the effects of nonuniform photon attenuation. The data were first reconstructed with zeroth-order Chang and a variant of the Bellini method, both of which utilize information from the nonuniform attenuation map. This nonuniform (NU) Bellini method compensates exactly for attenuation in the heart region, but is incorrect for other regions in the medium. These reconstructions were then used as the initial estimates in the iterative Chang, variable step-size (VSS) Chang, and Morozumi methods,m for one and five iterations. The average heart count (AHC) and average lung count (ALC) were calculated using region-of-interest (ROI) templates derived from the true activity map. The population mean LHR was tabulated as the ratio of the ALC to AHC. Using the same reconstruction procedure, the authors also calculated the sample mean LHR and standard deviation from 21 noisy 3D reconstructions

  5. 40 CFR 80.596 - How is a refinery motor vehicle diesel fuel volume baseline calculated?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false How is a refinery motor vehicle diesel... Requirements § 80.596 How is a refinery motor vehicle diesel fuel volume baseline calculated? (a) For purposes of this subpart, a refinery's motor vehicle diesel fuel volume baseline is calculated using the...

  6. Predicting Structure-Function Relations and Survival following Surgical and Bronchoscopic Lung Volume Reduction Treatment of Emphysema.

    Science.gov (United States)

    Mondoñedo, Jarred R; Suki, Béla

    2017-02-01

    Lung volume reduction surgery (LVRS) and bronchoscopic lung volume reduction (bLVR) are palliative treatments aimed at reducing hyperinflation in advanced emphysema. Previous work has evaluated functional improvements and survival advantage for these techniques, although their effects on the micromechanical environment in the lung have yet to be determined. Here, we introduce a computational model to simulate a force-based destruction of elastic networks representing emphysema progression, which we use to track the response to lung volume reduction via LVRS and bLVR. We find that (1) LVRS efficacy can be predicted based on pre-surgical network structure; (2) macroscopic functional improvements following bLVR are related to microscopic changes in mechanical force heterogeneity; and (3) both techniques improve aspects of survival and quality of life influenced by lung compliance, albeit while accelerating disease progression. Our model predictions yield unique insights into the microscopic origins underlying emphysema progression before and after lung volume reduction.

  7. Dynamic volume perfusion CT in patients with lung cancer: Baseline perfusion characteristics of different histological subtypes

    International Nuclear Information System (INIS)

    Shi, Jingyun; Schmid-Bindert, Gerald; Fink, Christian; Sudarski, Sonja; Apfaltrer, Paul; Pilz, Lothar R.; Liu, Bo; Haberland, Ulrike; Klotz, Ernst

    2013-01-01

    Objective: To evaluate dynamic volume perfusion CT (dVPCT) tumor baseline characteristics of three different subtypes of lung cancer in untreated patients. Materials and methods: 173 consecutive patients (131 men, 42 women; mean age 61 ± 10 years) with newly diagnosed lung cancer underwent dVPCT prior to biopsy. Tumor permeability, blood flow (BF), blood volume (BV) and mean transit time (MTT) were quantitatively assessed as well as tumor diameter and volume. Tumor subtypes were histologically determined and compared concerning their dVPCT results. dVPCT results were correlated to tumor diameter and volume. Results: Histology revealed adenocarcinoma in 88, squamous cell carcinoma in 54 and small cell lung cancer (SCLC) in 31 patients. Tumor permeability was significantly differing between adenocarcinoma, squamous cell carcinoma and SCLC (all p < 0.05). Tumor BF and BV were higher in adenocarcinomathan in SCLC (p = 0.001 and p = 0.0002 respectively). BV was also higher in squamous cell carcinoma compared to SCLC (p = 0.01). MTT was not differing between tumor subtypes. Regarding all tumors, tumor diameter did not correlate with any of the dVPCT parameters, whereas tumor volume was negatively associated with permeability, BF and BV (r = −0.22, −0.24, −0.24, all p < 0.05). In squamous cell carcinoma, tumor diameter und volume correlated with BV (r = 0.53 and r = −0.40, all p < 0.05). In SCLC, tumor diameter und volume correlated with MTT (r = 0.46 and r = 0.39, all p < 0.05). In adenocarcinoma, no association between morphological and functional tumor characteristics was observed. Conclusions: dVPCT parameters are only partially related to tumor diameter and volume and are significantly differing between lung cancer subtypes

  8. Inspiratory and expiratory computed tomographic volumetry for lung volume reduction surgery.

    Science.gov (United States)

    Morimura, Yuki; Chen, Fengshi; Sonobe, Makoto; Date, Hiroshi

    2013-06-01

    Three-dimensional (3D) computed tomographic (CT) volumetry has been introduced into the field of thoracic surgery, and a combination of inspiratory and expiratory 3D-CT volumetry provides useful data on regional pulmonary function as well as the volume of individual lung lobes. We report herein a case of a 62-year-old man with severe emphysema who had undergone lung volume reduction surgery (LVRS) to assess this technique as a tool for the evaluation of regional lung function and volume before and after LVRS. His postoperative pulmonary function was maintained in good condition despite a gradual slight decrease 2 years after LVRS. This trend was also confirmed by a combination of inspiratory and expiratory 3D-CT volumetry. We confirm that a combination of inspiratory and expiratory 3D-CT volumetry might be effective for the preoperative assessment of LVRS in order to determine the amount of lung tissue to be resected as well as for postoperative evaluation. This novel technique could, therefore, be used more widely to assess local lung function.

  9. Lung volume and expiratory flow rates from pre- to post-puberty.

    Science.gov (United States)

    Smith, Joshua R; Emerson, Sam R; Kurti, Stephanie P; Gandhi, Kirti; Harms, Craig A

    2015-08-01

    The purpose was to determine if the airways and lungs grow disproportionately from pre- to post-puberty in boys and girls. We hypothesized that the airways grow at a slower rate than lung volume (i.e. dysanapsis growth) during puberty and boys would exhibit more dysanaptic growth compared to girls. Twenty-one pre-pubescent children [11 boys (pre 10.1 ± 0.5 years, post 15.3 ± 0.5 years); 10 girls (pre 9.4 ± 1.0 years, post 14.1 ± 1.0 years)] performed pulmonary function tests (PFTs) ~5 years ago from an original cohort of 40 children. These 21 children performed PFTs, which included forced vital capacity (FVC) and forced expiratory flow at 50 % FVC (FEF50). Static pressure at 50 % of FVC [Pst(L)50 %] was estimated based on age. Dysanapsis ratio (DR) was calculated [FEF50 × FVC(-1) × Pst(L) 50 % (-1) ]. Maturation status was determined via Tanner stages. Stage of maturation was not different (p > 0.05) between boys and girls (4.2 ± 0.6 stage vs. 3.7 ± 0.7 stage, respectively). FVC and FEF50 increased (p 0.05) from pre- to post-puberty. FEF50 and FVC significantly increased and DR decreased (p puberty for both sexes. Post-puberty, boys had a significantly larger FVC, but FEF50, DR, and FEF50/FVC were not different (p > 0.05) compared to girls. These data suggest that dysanaptic growth occurs during puberty and that it is not different between boys and girls.

  10. Tumor Volume-Adapted Dosing in Stereotactic Ablative Radiotherapy of Lung Tumors

    Energy Technology Data Exchange (ETDEWEB)

    Trakul, Nicholas; Chang, Christine N.; Harris, Jeremy [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA (United States); Chapman, Christopher [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA (United States); University of Michigan School of Medicine, Ann Arbor, MI (United States); Rao, Aarti [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA (United States); University of California, Davis, School of Medicine, Davis, CA (United States); Shen, John [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA (United States); University of California, Irvine, School of Medicine, Irvine, CA (United States); Quinlan-Davidson, Sean [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA (United States); Department of Radiation Oncology, McMaster University, Juravinski Cancer Centre, Hamilton, Ontario (Canada); Filion, Edith J. [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA (United States); Departement de Medecine, Service de Radio-Oncologie, Centre Hospitalier de l' Universite de Montreal, Montreal, Quebec (Canada); Wakelee, Heather A.; Colevas, A. Dimitrios [Department of Medicine, Division of Oncology, Stanford University School of Medicine, Stanford, CA (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA (United States); Whyte, Richard I. [Department of Cardiothoracic Surgery, Division of General Thoracic Surgery, Stanford University School of Medicine, Stanford, CA (United States); Stanford Cancer Institute, Stanford University School of Medicine, Stanford, CA (United States); and others

    2012-09-01

    Purpose: Current stereotactic ablative radiotherapy (SABR) protocols for lung tumors prescribe a uniform dose regimen irrespective of tumor size. We report the outcomes of a lung tumor volume-adapted SABR dosing strategy. Methods and Materials: We retrospectively reviewed the outcomes in 111 patients with a total of 138 primary or metastatic lung tumors treated by SABR, including local control, regional control, distant metastasis, overall survival, and treatment toxicity. We also performed subset analysis on 83 patients with 97 tumors treated with a volume-adapted dosing strategy in which small tumors (gross tumor volume <12 mL) received single-fraction regimens with biologically effective doses (BED) <100 Gy (total dose, 18-25 Gy) (Group 1), and larger tumors (gross tumor volume {>=}12 mL) received multifraction regimens with BED {>=}100 Gy (total dose, 50-60 Gy in three to four fractions) (Group 2). Results: The median follow-up time was 13.5 months. Local control for Groups 1 and 2 was 91.4% and 92.5%, respectively (p = 0.24) at 12 months. For primary lung tumors only (excluding metastases), local control was 92.6% and 91.7%, respectively (p = 0.58). Regional control, freedom from distant metastasis, and overall survival did not differ significantly between Groups 1 and 2. Rates of radiation pneumonitis, chest wall toxicity, and esophagitis were low in both groups, but all Grade 3 toxicities developed in Group 2 (p = 0.02). Conclusion: A volume-adapted dosing approach for SABR of lung tumors seems to provide excellent local control for both small- and large-volume tumors and may reduce toxicity.

  11. Tumor Volume-Adapted Dosing in Stereotactic Ablative Radiotherapy of Lung Tumors

    International Nuclear Information System (INIS)

    Trakul, Nicholas; Chang, Christine N.; Harris, Jeremy; Chapman, Christopher; Rao, Aarti; Shen, John; Quinlan-Davidson, Sean; Filion, Edith J.; Wakelee, Heather A.; Colevas, A. Dimitrios; Whyte, Richard I.

    2012-01-01

    Purpose: Current stereotactic ablative radiotherapy (SABR) protocols for lung tumors prescribe a uniform dose regimen irrespective of tumor size. We report the outcomes of a lung tumor volume-adapted SABR dosing strategy. Methods and Materials: We retrospectively reviewed the outcomes in 111 patients with a total of 138 primary or metastatic lung tumors treated by SABR, including local control, regional control, distant metastasis, overall survival, and treatment toxicity. We also performed subset analysis on 83 patients with 97 tumors treated with a volume-adapted dosing strategy in which small tumors (gross tumor volume <12 mL) received single-fraction regimens with biologically effective doses (BED) <100 Gy (total dose, 18–25 Gy) (Group 1), and larger tumors (gross tumor volume ≥12 mL) received multifraction regimens with BED ≥100 Gy (total dose, 50–60 Gy in three to four fractions) (Group 2). Results: The median follow-up time was 13.5 months. Local control for Groups 1 and 2 was 91.4% and 92.5%, respectively (p = 0.24) at 12 months. For primary lung tumors only (excluding metastases), local control was 92.6% and 91.7%, respectively (p = 0.58). Regional control, freedom from distant metastasis, and overall survival did not differ significantly between Groups 1 and 2. Rates of radiation pneumonitis, chest wall toxicity, and esophagitis were low in both groups, but all Grade 3 toxicities developed in Group 2 (p = 0.02). Conclusion: A volume-adapted dosing approach for SABR of lung tumors seems to provide excellent local control for both small- and large-volume tumors and may reduce toxicity.

  12. Normal expiratory flow rate and lung volumes in patients with combined emphysema and interstitial lung disease: a case series and literature review.

    Science.gov (United States)

    Heathcote, Karen L; Cockcroft, Donald W; Fladeland, Derek A; Fenton, Mark E

    2011-01-01

    Pulmonary function tests in patients with idiopathic pulmonary fibrosis characteristically show a restrictive pattern including small lung volumes and increased expiratory flow rates resulting from a reduction in pulmonary compliance due to diffuse fibrosis. Conversely, an obstructive pattern with hyperinflation results in emphysema by loss of elastic recoil, expiratory collapse of the peripheral airways and air trapping. When the diseases coexist, pulmonary volumes are compensated, and a smaller than expected reduction or even normal lung volumes can be found. The present report describes 10 patients with progressive breathlessness, three of whom experienced severe limitation in their quality of life. All patients showed lung interstitial involvement and emphysema on computed tomography scan of the chest. The 10 patients showed normal spirometry and lung volumes with severe compromise of gas exchange. Normal lung volumes do not exclude diagnosis of idiopathic pulmonary fibrosis in patients with concomitant emphysema. The relatively preserved lung volumes may underestimate the severity of idiopathic pulmonary fibrosis and attenuate its effects on lung function parameters.

  13. Normal Expiratory Flow Rate and Lung Volumes in Patients with Combined Emphysema and Interstitial Lung Disease: A Case Series and Literature Review

    Directory of Open Access Journals (Sweden)

    Karen L Heathcote

    2011-01-01

    Full Text Available Pulmonary function tests in patients with idiopathic pulmonary fibrosis characteristically show a restrictive pattern including small lung volumes and increased expiratory flow rates resulting from a reduction in pulmonary compliance due to diffuse fibrosis. Conversely, an obstructive pattern with hyperinflation results in emphysema by loss of elastic recoil, expiratory collapse of the peripheral airways and air trapping. When the diseases coexist, pulmonary volumes are compensated, and a smaller than expected reduction or even normal lung volumes can be found. The present report describes 10 patients with progressive breathlessness, three of whom experienced severe limitation in their quality of life. All patients showed lung interstitial involvement and emphysema on computed tomography scan of the chest. The 10 patients showed normal spirometry and lung volumes with severe compromise of gas exchange. Normal lung volumes do not exclude diagnosis of idiopathic pulmonary fibrosis in patients with concomitant emphysema. The relatively preserved lung volumes may underestimate the severity of idiopathic pulmonary fibrosis and attenuate its effects on lung function parameters.

  14. Assessment of early bronchiectasis in young children with cystic fibrosis is dependent on lung volume

    NARCIS (Netherlands)

    M.P.L. Bard (Martin); K. Graniel (Karla); J. Park (Judy); N.H. de Klerk (Nicholas); P.D. Sly; C.P. Murray (Conor); H.A.W.M. Tiddens (Harm); S. Stick

    2013-01-01

    textabstractObjective: The aim of this study was to determine whether assessment of early CT scan-detected bronchiectasis in young children with cystic fibrosis (CF) depends on lung volume. Methods: This study, approved by the hospital ethics committee, included 40 young children with CF from a

  15. Lung volume reduction coil treatment for patients with severe emphysema : a European multicentre trial

    NARCIS (Netherlands)

    Deslee, Gaetan; Klooster, Karin; Hetzel, Martin; Stanzel, Franz; Kessler, Romain; Marquette, Charles-Hugo; Witt, Christian; Blaas, Stefan; Gesierich, Wolfgang; Herth, Felix J. F.; Hetzel, Juergen; van Rikxoort, Eva M.; Slebos, Dirk-Jan

    2014-01-01

    Background The lung volume reduction (LVR) coil is a minimally invasive bronchoscopic nitinol device designed to reduce hyperinflation and improve elastic recoil in severe emphysema. We investigated the feasibility, safety and efficacy of LVR coil treatment in a prospective multicentre cohort trial

  16. Mechanisms controlling the volume of pleural fluid and extravascular lung water

    Directory of Open Access Journals (Sweden)

    G. Miserocchi

    2009-12-01

    Full Text Available Pleural and interstitial lung fluid volumes are strictly controlled and maintained at the minimum thanks to the ability of lymphatics to match the increase in filtration rate. In the pleural cavity, fluid accumulation is easily accommodated by retraction of lung and chest wall (high compliance of the pleural space; the increase of lymph flow per unit increase in pleural fluid volume is high due to the great extension of the parietal lymphatic. However, for the lung interstitium, the increase in lymph flow to match increased filtration does not need to be so great. In fact, increased filtration only causes a minor increase in extravascular water volume (<10% due to a marked increase in interstitial pulmonary pressure (low compliance of the extracellular matrix which, in turn, buffers further filtration. Accordingly, a less extended lymphatic network is needed. The efficiency of lymphatic control is achieved through a high lymphatic conductance in the pleural fluid and through a low interstitial compliance for the lung interstitium. Fluid volume in both compartments is so strictly controlled that it is difficult to detect initial deviations from the physiological state; thus, a great physiological advantage turns to be a disadvantage on a clinical basis as it prevents an early diagnosis of developing disease.

  17. Treatment of emphysema using bronchoscopic lung volume reduction coil technology : an update on efficacy and safety

    NARCIS (Netherlands)

    Hartman, Jorine E.; Klooster, Karin; ten Hacken, Nick H. T.; Slebos, Dirk-Jan

    2015-01-01

    In the last decade several promising bronchoscopic lung volume reduction (BLVR) treatments were developed and investigated. One of these treatments is BLVR treatment with coils. The advantage of this specific treatment is that it works independently of collateral flow, and also shows promise for

  18. Adaptive Support Ventilation May Deliver Unwanted Respiratory Rate-Tidal Volume Combinations in Patients with Acute Lung Injury Ventilated According to an Open Lung Concept

    NARCIS (Netherlands)

    Dongelmans, Dave A.; Paulus, Frederique; Veelo, Denise P.; Binnekade, Jan M.; Vroom, Margreeth B.; Schultz, Marcus J.

    2011-01-01

    Background: With adaptive support ventilation, respiratory rate and tidal volume (V(T)) are a function of the Otis least work of breathing formula. We hypothesized that adaptive support ventilation in an open lung ventilator strategy would deliver higher V(T)s to patients with acute lung injury.

  19. Lung Deposition Calculations for Radioactive Aerosol Particles Originating from Caves and Uranium Mines

    International Nuclear Information System (INIS)

    Alfoldy, B.; Torok, Sz.; Winkler, R.

    2001-01-01

    Full text: The present study simulates lung deposition of radioactive aerosol particles originating from the atmosphere of a therapeutic cave (Szemlohegyi cave, Budapest) and several uranium mines. Particle deposition patterns and surface densities have been calculated by the stochastic lung model of Koblinger and Hofmann. In the model, deposition can be caused by the simultaneous effects of Brownian motion, inertial impaction and gravitational settling. The calculations were carried out by considering the aerosol particle size distribution and radon concentration of the atmosphere of the cave and mines. The deposition was computed in the whole lung, in characteristic parts of the respiratory system such as extrathoracic, tracheobronchial, acinar and alveolar regions and in the singe airway generations at different flow rates for adults. The adverse health effects of inhaled radionuclides strongly depend from the local deposition density values in cellular dimensions. Thus we will built in the results to a cellular effects model of Balashazy and Hofmann for the simulation of the pathological effects of inhaled radionuclides for risk assessment. (author)

  20. Pulmonary blood volume and transit time in cirrhosis: relation to lung function

    DEFF Research Database (Denmark)

    Møller, Søren; Burchardt, H; Øgard, CG

    2006-01-01

    BACKGROUND/AIMS: In cirrhosis a systemic vasodilatation leads to an abnormal distribution of the blood volume with a contracted central blood volume. In addition, the patients have a ventilation/perfusion imbalance with a low diffusing capacity. As the size of the pulmonary blood volume (PBV) has...... not been determined separately we assessed PBV and pulmonary transit time (PTT) in relation to lung function in patients with cirrhosis and in controls. METHODS: Pulmonary and cardiac haemodynamics and transit times were determined by radionuclide techniques in 22 patients with alcoholic cirrhosis......, in the controls, Pvolume...

  1. Effect of tidal volume on extravascular lung water content during one-lung ventilation for video-assisted thoracoscopic surgery: a randomised, controlled trial.

    Science.gov (United States)

    Qutub, Hatem; El-Tahan, Mohamed R; Mowafi, Hany A; El Ghoneimy, Yasser F; Regal, Mohamed A; Al Saflan, AbdulHadi A

    2014-09-01

    The use of low tidal volume during one-lung ventilation (OLV) has been shown to attenuate the incidence of acute lung injury after thoracic surgery. To test the effect of tidal volume during OLV for video-assisted thoracoscopic surgery on the extravascular lung water content index (EVLWI). A randomised, double-blind, controlled study. Single university hospital. Thirty-nine patients scheduled for elective video-assisted thoracoscopic surgery. Patients were randomly assigned to one of three groups (n = 13 per group) to ventilate the dependent lung with a tidal volume of 4, 6 or 8 ml  kg(-1) predicted body weight with I:E ratio of 1:2.5 and PEEP of 5 cm H2O. The primary outcomes were perioperative changes in EVLWI and EVLWI to intrathoracic blood volume index (ITBVI) ratio. Secondary outcomes included haemodynamics, oxygenation indices, incidences of postoperative acute lung injury, atelectasis, pneumonia, morbidity and 30-day mortality. A tidal volume of 4 compared with 6 and 8 ml  kg(-1) after 45 min of OLV resulted in an EVLWI of 4.1 [95% confidence interval (CI) 3.5 to 4.7] compared with 7.7 (95% CI 6.7 to 8.6) and 8.6 (95% CI 7.5 to 9.7) ml  kg(-1), respectively (P tidal volume of 4 ml kg during OLV was associated with less lung water content than with larger tidal volumes of 6 to 8 ml kg(-1), although no patient developed acute lung injury. Further studies are required to address the usefulness of EVLWI as a marker for the development of postoperative acute lung injury after the use of a low tidal volume during OLV in patients undergoing pulmonary resection. Clinicaltrials.gov identifier: NCT01762709.

  2. Calculation of microplanar beam dose profiles in a tissue/lung/tissue phantom

    International Nuclear Information System (INIS)

    Company, F.Z.; Allen, B.J.

    1998-01-01

    Recent advances in synchrotron generated x-ray beams with a high fluence rate permit investigation of the application of an array of closely spaced, parallel or converging microplanar beams in radiotherapy. The proposed technique takes advantage of the hypothesized repair mechanism of capillary cells between alternate microbeam zones, which regenerates the lethally irradiated endothelial cells. The lateral and depth doses of 100 keV microplanar beams are investigated for different beam dimensions and spacings in a tissue, lung and tissue/lung/tissue phantom. The EGS4 Monte Carlo code is used to calculate dose profiles at different depths and bundles of beams (up to 20x20cm square cross section). The maximum dose on the beam axis (peak) and the minimum interbeam dose (valley) are compared at different depths, bundles, heights, widths and beam spacings. (author)

  3. Pulmonary blood volume and transit time in cirrhosis: relation to lung function

    DEFF Research Database (Denmark)

    Møller, Søren; Burchardt, H; Øgard, CG

    2006-01-01

    BACKGROUND/AIMS: In cirrhosis a systemic vasodilatation leads to an abnormal distribution of the blood volume with a contracted central blood volume. In addition, the patients have a ventilation/perfusion imbalance with a low diffusing capacity. As the size of the pulmonary blood volume (PBV) has...... in cirrhosis. The relation between PBV and PTT and the low diffusing capacity suggests the pulmonary vascular compartment as an important element in the pathophysiology of the lung dysfunction in cirrhosis....... not been determined separately we assessed PBV and pulmonary transit time (PTT) in relation to lung function in patients with cirrhosis and in controls. METHODS: Pulmonary and cardiac haemodynamics and transit times were determined by radionuclide techniques in 22 patients with alcoholic cirrhosis...

  4. Converging Stereotactic Radiotherapy Using Kilovoltage X-Rays: Experimental Irradiation of Normal Rabbit Lung and Dose-Volume Analysis With Monte Carlo Simulation

    International Nuclear Information System (INIS)

    Kawase, Takatsugu; Kunieda, Etsuo; Deloar, Hossain M.; Tsunoo, Takanori; Seki, Satoshi; Oku, Yohei; Saitoh, Hidetoshi; Saito, Kimiaki; Ogawa, Eileen N.; Ishizaka, Akitoshi; Kameyama, Kaori; Kubo, Atsushi

    2009-01-01

    Purpose: To validate the feasibility of developing a radiotherapy unit with kilovoltage X-rays through actual irradiation of live rabbit lungs, and to explore the practical issues anticipated in future clinical application to humans through Monte Carlo dose simulation. Methods and Materials: A converging stereotactic irradiation unit was developed, consisting of a modified diagnostic computed tomography (CT) scanner. A tiny cylindrical volume in 13 normal rabbit lungs was individually irradiated with single fractional absorbed doses of 15, 30, 45, and 60 Gy. Observational CT scanning of the whole lung was performed every 2 weeks for 30 weeks after irradiation. After 30 weeks, histopathologic specimens of the lungs were examined. Dose distribution was simulated using the Monte Carlo method, and dose-volume histograms were calculated according to the data. A trial estimation of the effect of respiratory movement on dose distribution was made. Results: A localized hypodense change and subsequent reticular opacity around the planning target volume (PTV) were observed in CT images of rabbit lungs. Dose-volume histograms of the PTVs and organs at risk showed a focused dose distribution to the target and sufficient dose lowering in the organs at risk. Our estimate of the dose distribution, taking respiratory movement into account, revealed dose reduction in the PTV. Conclusions: A converging stereotactic irradiation unit using kilovoltage X-rays was able to generate a focused radiobiologic reaction in rabbit lungs. Dose-volume histogram analysis and estimated sagittal dose distribution, considering respiratory movement, clarified the characteristics of the irradiation received from this type of unit.

  5. Static inflation and deflation pressure–volume curves from excised lungs of marine mammals

    Science.gov (United States)

    Fahlman, Andreas; Loring, Stephen H.; Ferrigno, Massimo; Moore, Colby; Early, Greg; Niemeyer, Misty; Lentell, Betty; Wenzel, Frederic; Joy, Ruth; Moore, Michael J.

    2011-01-01

    SUMMARY Excised lungs from eight marine mammal species [harp seal (Pagophilus groenlandicus), harbor seal (Phoca vitulina), gray seal (Halichoerus grypush), Atlantic white-sided dolphin (Lagenorhynchus acutus), common dolphin (Delphinus delphis), Risso's dolphin (Grampus griseus), long-finned pilot whale (Globicephala melas) and harbor porpoise (Phocoena phocoena)] were used to determine the minimum air volume of the relaxed lung (MAV, N=15), the elastic properties (pressure–volume curves, N=24) of the respiratory system and the total lung capacity (TLC). Our data indicate that mass-specific TLC (sTLC, l kg–1) does not differ between species or groups (odontocete vs phocid) and agree with that estimated (TLCest) from body mass (Mb) by applying the equation: TLCest=0.135 Mb0.92. Measured MAV was on average 7% of TLC, with a range from 0 to 16%. The pressure–volume curves were similar among species on inflation but diverged during deflation in phocids in comparison with odontocetes. These differences provide a structural basis for observed species differences in the depth at which lungs collapse and gas exchange ceases. PMID:22031747

  6. The method of estimating the irradiated lung volume in primary breast irradiation

    International Nuclear Information System (INIS)

    Leite, Miguel Torres Teixeira; Marques, Iara Silva; Geraldo, Jony Marques

    1999-01-01

    Tangential breast fields irradiation usually includes some volume of lung and it is occasionally associated with pneumonitis. The estimation of the amount of lung irradiated can be determined measuring the central lung distance (CLD) by the port films, and it must be inferior to 2.5 cm. The purpose of this study was to determine through a linear regression analysis the relationship between CLD and the geometrical parameters of the treatment, and to develop an equation to predict this volume. The studied population consisted of 100 patients who received definitive radiation for clinical stage I and II breast cancer between January, 1996 and June, 1997. According to the contour of the breast and thorax was determined the angle of the tangential fields. In 71% of the patients the CLD measured by the portal films were superior to 2.5 cm, requiring a new beam arrangement. We develop a simple and convenient quantitative model to predict the irradiated lung volume based on portal films. We need further analysis in order to include variables and antomical variations. (author)

  7. Volume calculations of coarse woody debris; evaluation of coarse woody debris volume calculations and consequences for coarse woody debris volume estimates in forest reserves

    NARCIS (Netherlands)

    Wijdeven, S.M.J.; Vaessen, O.H.B.; Hees, van A.F.M.; Olsthoorn, A.F.M.

    2005-01-01

    Dead wood is recognized as one of the key indicators for sustainable forest management and biodiversity. Accurate assessments of dead wood volume are thus necessary. In this study New volume models were designed based on actual volume measurements of coarse woody debris. The New generic model

  8. CT-based dose calculations and in vivo dosimetry for lung cancer treatment

    International Nuclear Information System (INIS)

    Essers, M.; Lanson, J.H.; Leunens, G.; Schnabel, T.; Mijnheer, B.J.

    1995-01-01

    Reliable CT-based dose calculations and dosimetric quality control are essential for the introduction of new conformal techniques for the treatment of lung cancer. The first aim of this study was therefore to check the accuracy of dose calculations based on CT-densities, using a simple inhomogeneity correction model, for lung cancer patients irradiated with an AP-PA treatment technique. Second, the use of diodes for absolute exit dose measurements and an Electronic Portal Imaging Device (EPID) for relative transmission dose verification was investigated for 22 and 12 patients, respectively. The measured dose values were compared with calculations performed using our 3-dimensional treatment planning system, using CT-densities or assuming the patient to be water-equivalent. Using water-equivalent calculations, the actual exit dose value under lung was, on average, underestimated by 30%, with an overall spread of 10% (1 SD). Using inhomogeneity corrections, the exit dose was, on average, overestimated by 4%, with an overall spread of 6% (1 SD). Only 2% of the average deviation was due to the inhomogeneity correction model. An uncertainty in exit dose calculation of 2.5% (1 SD) could be explained by organ motion, resulting from the ventilatory or cardiac cycle. The most important reason for the large overall spread was, however, the uncertainty involved in performing point measurements: about 4% (1 SD). This difference resulted from the systematic and random deviation in patient set-up and therefore in diode position with respect to patient anatomy. Transmission and exit dose values agreed with an average difference of 1.1%. Transmission dose profiles also showed good agreement with calculated exit dose profiles. Our study shows that, for this treatment technique, the dose in the thorax region is quite accurately predicted using CT-based dose calculations, even if a simple inhomogeneity correction model is used. Point detectors such as diodes are not suitable for exit

  9. Influence on dose calculation by difference of dose calculation algorithms in stereotactic lung irradiation. Comparison of pencil beam convolution (inhomogeneity correction: batho power law) and analytical anisotropic algorithm

    International Nuclear Information System (INIS)

    Tachibana, Masayuki; Noguchi, Yoshitaka; Fukunaga, Jyunichi; Hirano, Naomi; Yoshidome, Satoshi; Hirose, Takaaki

    2009-01-01

    The monitor unit (MU) was calculated by pencil beam convolution (inhomogeneity correction algorithm: batho power law) [PBC (BPL)] which is the dose calculation algorithm based on measurement in the past in the stereotactic lung irradiation study. The recalculation was done by analytical anisotropic algorithm (AAA), which is the dose calculation algorithm based on theory data. The MU calculated by PBC (BPL) and AAA was compared for each field. In the result of the comparison of 1031 fields in 136 cases, the MU calculated by PBC (BPL) was about 2% smaller than that calculated by AAA. This depends on whether one does the calculation concerning the extension of the second electrons. In particular, the difference in the MU is influenced by the X-ray energy. With the same X-ray energy, when the irradiation field size is small, the lung pass length is long, the lung pass length percentage is large, and the CT value of the lung is low, and the difference of MU is increased. (author)

  10. Tricuspid valve dysplasia with severe tricuspid regurgitation: fetal pulmonary artery size predicts lung viability in the presence of small lung volumes.

    Science.gov (United States)

    Nathan, A T; Marino, B S; Dominguez, T; Tabbutt, S; Nicolson, S; Donaghue, D D; Spray, T L; Rychik, J

    2010-01-01

    Congenital tricuspid valve disease (Ebstein's anomaly, tricuspid valve dysplasia) with severe tricuspid regurgitation and cardiomegaly is associated with poor prognosis. Fetal echocardiography can accurately measure right atrial enlargement, which is associated with a poor prognosis in the fetus with tricuspid valve disease. Fetal lung volumetric assessments have been used in an attempt to predict viability of fetuses using ultrasonogram and prenatal MRI. We describe a fetus with tricuspid dysplasia, severe tricuspid regurgitation, right atrial enlargement and markedly reduced lung volumes. The early gestational onset of cardiomegaly with bilateral lung compression raised the possibility of severe lung hypoplasia with decreased broncho-alveolar development. Use of fetal echocardiography with measurement of pulmonary artery size combined with prenatal MRI scanning of lung volumes resulted in an improved understanding of this anomaly and directed the management strategy towards a successful Fontan circulation. 2010 S. Karger AG, Basel.

  11. Radiotherapy for non-small cell lung cancer: volume definition and patient selection. Annecy 1998 international Association for the study of lung cancer (IASLC) Workshop recommendations

    International Nuclear Information System (INIS)

    Mornex, F.; Loubeyre, P.; Van houtte, P.; Scalliet, P.

    1998-01-01

    Chemo-radiation is the standard treatment of unresectable, locally advanced non-small cell lung cancer, with a mean dose of 60-66 Gy, excluding escalation dose schemes. The standard treated volume includes primary tumor, ipsilateral hilar and mediastinal nodes, supraclavicular and contralateral nodes as well, regardless of the node status. This work tries to answer the question of the optimal volume to be treated. Drainage routes analysis is in favor of large volumes, while toxicity analysis favors small volumes. Combined modality treatment may increase the observed toxicity. The optimal volume definition is difficult, and requires available conformal therapy tools. Patients selection is another important issue. A volume definition is then attempted, based on the IASLC (International Association for the Study of Lung Cancer) Annecy workshop experience, highlighting the inter-observers discrepancies, and suggests basic recommendations to harmonize volume definition. (author)

  12. Expiratory flow limitation and operating lung volumes during exercise in older and younger adults.

    Science.gov (United States)

    Smith, Joshua R; Kurti, Stephanie P; Meskimen, Kayla; Harms, Craig A

    2017-06-01

    We determined the effect of aging on expiratory flow limitation (EFL) and operating lung volumes when matched for lung size. We hypothesized that older adults will exhibit greater EFL and increases in EELV during exercise compared to younger controls. Ten older (5M/5W; >60years old) and nineteen height-matched young adults (10M/9W) were recruited. Young adults were matched for%predicted forced vital capacity (FVC) (Y-matched%Pred FVC; n=10) and absolute FVC (Y-matched FVC; n=10). Tidal flow-volume loops were recorded during the incremental exercise test with maximal flow-volume loops measured pre- and post-exercise. Compared to younger controls, older adults exhibited more EFL at ventilations of 26, 35, 51, and 80L/min. The older group had higher end-inspiratory lung volume compared to Y-matched%Pred FVC group during submaximal ventilations. The older group increased EELV during exercise, while EELV stayed below resting in the Y-matched%Pred FVC group. These data suggest older adults exhibit more EFL and increase EELV earlier during exercise compared to younger adults. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Diameter structure modeling and the calculation of plantation volume of black poplar clones

    Directory of Open Access Journals (Sweden)

    Andrašev Siniša

    2004-01-01

    Full Text Available A method of diameter structure modeling was applied in the calculation of plantation (stand volume of two black poplar clones in the section Aigeiros (Duby: 618 (Lux and S1-8. Diameter structure modeling by Weibull function makes it possible to calculate the plantation volume by volume line. Based on the comparison of the proposed method with the existing methods, the obtained error of plantation volume was less than 2%. Diameter structure modeling and the calculation of plantation volume by diameter structure model, by the regularity of diameter distribution, enables a better analysis of the production level and assortment structure and it can be used in the construction of yield and increment tables.

  14. Analysis of the static pressure volume curve of the lung in experimentally induced pulmonary damage by CT-densitometry

    International Nuclear Information System (INIS)

    David, M.; Karmrodt, J.; Herwelling, A.; Bletz, C.; David, S.; Heussel, C.P.; Markstaller, K.

    2005-01-01

    Purpose: To study quantitative changes of lung density distributions when recording in- and expiratory static pressure-volume curves by single slice computed tomography (CT). Materials and Methods: Static in- and expiratory pressure volume curves (0 to 1000 ml, increments of 100 ml) were obtained in random order in 10 pigs after induction of lung damage by saline lavage. Simultaneously, CT acquisitions (slice thickness 1 mm, temporal increment 2 s) were performed in a single slice (3 cm below the carina). In each CT image lung segmentation and planimetry of defined density ranges were achieved. The lung density ranges were defined as: hyperinflated (-1024 to -910 HU), normal aerated (-910 to -600 HU), poorly aerated (-600 to -300 HU), and non aerated (-300 to 200 HU) lung. Fractional areas of defined density ranges in percentage of total lung area were compared to recorded volume increments and airway pressures (atmospheric pressure, lower inflection point (LIP), LIP*0.5, LIP*1.5, peak airway pressure) of in- and expiratory pressure-volume curves. Results: Quantitative analysis of defined density ranges showed no differences between in- and expiratory pressure-volume curves. The amount of poorly aerated lung decreased and normal aerated lung increased constantly when airway pressure and volume were increased during inspiratory pressure-volume curves and vice versa during expiratory pressure-volume loops. Conclusion: Recruitment and derecruitment of lung atelectasis during registration of static in- and expiratory pressure-volume loops occurred constantly, but not in a stepwise manner. CT was shown to be an appropriate method to analyse these recruitment process. (orig.)

  15. Evaluation of dose according to the volume and respiratory range during SBRT in lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Deuk Hee [Dept. of Radiation Oncology, Busan Paik Hospital, Inje University, Busan (Korea, Republic of); Park, Eun Tae; Kim, Jung Hoon; Kang, Se Seik [Dept. of Radiological Science, College of Health Sciences, Catholic University of Pusan, Busan (Korea, Republic of)

    2016-09-15

    Stereotactic body radiotherapy is effective technic in radiotherapy for low stage lung cancer. But lung cancer is affected by respiratory so accurately concentrate high dose to the target is very difficult. In this study, evaluated the target volume according to how to take the image. And evaluated the dose by photoluminescence glass dosimeter according to how to contour the volume and respiratory range. As a result, evaluated the 4D CT volume was 10.4 cm{sup 3} which was closest value of real size target. And in dose case is internal target volume dose was 10.82, 16.88, 21.90 Gy when prescribed dose was 10, 15, 20 Gy and it was the highest dose. Respiratory gated radiotherapy dose was more higher than internal target volume. But it made little difference by respiratory range. Therefore, when moving cancer treatment, acquiring image by 4D CT, contouring internal target volume and respiratory gated radiotherapy technic would be the best way.

  16. Evaluation of dose according to the volume and respiratory range during SBRT in lung cancer

    International Nuclear Information System (INIS)

    Lee, Deuk Hee; Park, Eun Tae; Kim, Jung Hoon; Kang, Se Seik

    2016-01-01

    Stereotactic body radiotherapy is effective technic in radiotherapy for low stage lung cancer. But lung cancer is affected by respiratory so accurately concentrate high dose to the target is very difficult. In this study, evaluated the target volume according to how to take the image. And evaluated the dose by photoluminescence glass dosimeter according to how to contour the volume and respiratory range. As a result, evaluated the 4D CT volume was 10.4 cm 3 which was closest value of real size target. And in dose case is internal target volume dose was 10.82, 16.88, 21.90 Gy when prescribed dose was 10, 15, 20 Gy and it was the highest dose. Respiratory gated radiotherapy dose was more higher than internal target volume. But it made little difference by respiratory range. Therefore, when moving cancer treatment, acquiring image by 4D CT, contouring internal target volume and respiratory gated radiotherapy technic would be the best way

  17. Functional evaluation of lung by Xe-133 lung ventilation scintigraphy before and after lung volume reduction surgery (LVRS) in patients with pulmonary emphysema

    International Nuclear Information System (INIS)

    Kurose, Taichi; Okumura, Yoshihiro; Sato, Shuhei

    2004-01-01

    We evaluated the respiratory functions of patients with pulmonary emphysema who underwent lung volume reduction surgery (LVRS) by the mean transit time (MTT) with Xe-133 lung ventilation scintigraphy, forced expiration volume in 1 sec (FEV1.0), residual volume (RV), distance walked in 6 min (6-min walk), and the Hugh-Jones classification (H-J classification) before and after LVRS. In 69 patients with pulmonary emphysema (62 men, 7 women; age range, 47-75 years; mean age, 65.4 years±6.1, preoperative H-J classification, III (two were II)-V) who underwent LVRS, all preoperative and postoperative parameters (MTT 3 weeks after LVRS and the others 3 months after LVRS) were judged statistically by the Wilcoxon signed-ranks test and Odds ratio. Every postoperative parameter was improved with a significant difference (P<0.05) compared to preoperative parameters. MTT at 3 weeks after LVRS was not associated with %FEV1.0 and the H-J classification at 3 months after LVRS, but was associated with RV and a 6-min walk at 3 months after LVRS. MTT was useful for the clinical evaluation of aerobic capability after LVRS. (author)

  18. Efficacy of lung volume optimization maneuver monitored by optoelectronic pletismography in the management of congenital diaphragmatic hernia

    Directory of Open Access Journals (Sweden)

    G. Lista

    2017-01-01

    We report a case of left CDH with severe lung hypoplasia, managed applying open lung strategy in HFOV (pre-surgery period and in Assist-Control with Volume Guarantee (post-surgery period, guided by SpO2 changes, TcPO2 and TcPCO2 monitoring. Opto-electronic plethysmography was used to measure end-expiratory chest wall volume changes (ΔEEcw related to lung volume variations occurring during pressure changes. OEP confirmed the efficacy of using SpO2 and transcutaneous gas monitoring during this recruitment maneuver.

  19. 40 CFR 80.599 - How do I calculate volume balances for designation purposes?

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Motor Vehicle Diesel Fuel... June 30, 2013. July 1, 2013 May 31, 2014. (2) [Reserved] (b) Volume balance for motor vehicle diesel fuel. (1) A facility's motor vehicle diesel fuel volume balance is calculated as follows: MVB = MVI−MVO...

  20. Clinicopathologic Analysis of Microscopic Extension in Lung Adenocarcinoma: Defining Clinical Target Volume for Radiotherapy

    International Nuclear Information System (INIS)

    Grills, Inga S.; Fitch, Dwight L.; Goldstein, Neal S.; Yan Di; Chmielewski, Gary W.; Welsh, Robert J.; Kestin, Larry L.

    2007-01-01

    Purpose: To determine the gross tumor volume (GTV) to clinical target volume margin for non-small-cell lung cancer treatment planning. Methods: A total of 35 patients with Stage T1N0 adenocarcinoma underwent wedge resection plus immediate lobectomy. The gross tumor size and microscopic extension distance beyond the gross tumor were measured. The nuclear grade and percentage of bronchoalveolar features were analyzed for association with microscopic extension. The gross tumor dimensions were measured on a computed tomography (CT) scan (lung and mediastinal windows) and compared with the pathologic dimensions. The potential coverage of microscopic extension for two different lung stereotactic radiotherapy regimens was evaluated. Results: The mean microscopic extension distance beyond the gross tumor was 7.2 mm and varied according to grade (10.1, 7.0, and 3.5 mm for Grade 1 to 3, respectively, p < 0.01). The 90th percentile for microscopic extension was 12.0 mm (13.0, 9.7, and 4.4 mm for Grade 1 to 3, respectively). The CT lung windows correlated better with the pathologic size than did the mediastinal windows (gross pathologic size overestimated by a mean of 5.8 mm; composite size [gross plus microscopic extension] underestimated by a mean of 1.2 mm). For a GTV contoured on the CT lung windows, the margin required to cover microscopic extension for 90% of the cases would be 9 mm (9, 7, and 4 mm for Grade 1 to 3, respectively). The potential microscopic extension dosimetric coverage (55 Gy) varied substantially between the stereotactic radiotherapy schedules. Conclusion: For lung adenocarcinomas, the GTV should be contoured using CT lung windows. Although a GTV based on the CT lung windows would underestimate the gross tumor size plus microscopic extension by only 1.2 mm for the average case, the clinical target volume expansion required to cover the microscopic extension in 90% of cases could be as large as 9 mm, although considerably smaller for high-grade tumors

  1. Survival in pediatric lung transplantation: The effect of center volume and expertise.

    Science.gov (United States)

    Khan, Muhammad S; Zhang, Wei; Taylor, Rachel A; Dean McKenzie, E; Mallory, George B; Schecter, Marc G; Morales, David L S; Heinle, Jeffrey S; Adachi, Iki

    2015-08-01

    Institutional operative volume has been shown to impact outcomes of various procedures including lung transplantation (LTx). We sought to determine whether this holds true with pediatric LTx by comparing outcomes of adult centers (with larger overall volume) to those of pediatric centers (with smaller volume but more pediatric-specific experience). A retrospective analysis of the Organ Procurement and Transplant Network data was performed. Centers were categorized as either adult (LTx volume predominantly in adult patients), high-volume pediatric (HVP, ≥4 LTxs/year), or low-volume pediatric (LVP, HVP 3 [5%], LVP 8 [13%]). Although adult centers had larger overall LTx volume, their pediatric experiences were severely limited (median 1/year). In younger children, HVP centers were significantly better than LVP centers for patient survival (half-life: 7.3 vs 2.9 years, p = 0.002). Similarly, in older children and adolescents, HVP centers were significantly better than adult centers for patient survival (half-life: 4.6 vs 2.5 years, p = 0.001). Of note, even LVP centers tended to have longer patient survival than adult centers (p = 0.064). Multivariable analysis identified adult centers as an independent risk factor for graft failure (hazard ratio: 1.5, p < 0.001) as with LVP (hazard ratio: 1.3, p = 0.0078). Despite larger overall clinical volume, outcomes among pediatric LTx recipients in adult centers are not superior to those of pediatric centers. Not only center volume but pediatric-specific experience has an impact on outcomes in pediatric LTx. Copyright © 2015 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  2. Ultrasound automated volume calculation in reproduction and in pregnancy.

    Science.gov (United States)

    Ata, Baris; Tulandi, Togas

    2011-06-01

    To review studies assessing the application of ultrasound automated volume calculation in reproductive medicine. We performed a literature search using the keywords "SonoAVC, sonography-based automated volume calculation, automated ultrasound, 3D ultrasound, antral follicle, follicle volume, follicle monitoring, follicle tracking, in vitro fertilization, controlled ovarian hyperstimulation, embryo volume, embryonic volume, gestational sac, and fetal volume" and conducted the search in PubMed, Medline, EMBASE, and the Cochrane Database of Systematic Reviews. Reference lists of identified reports were manually searched for other relevant publications. Automated volume measurements are in very good agreement with actual volumes of the assessed structures or with other validated measurement methods. The technique seems to provide reliable and highly reproducible results under a variety of conditions. Automated measurements take less time than manual measurements. Ultrasound automated volume calculation is a promising new technology which is already used in daily practice especially for assisted reproduction. Improvements to the technology will undoubtedly render it more effective and increase its use. Copyright © 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  3. [Prediction of the efficiency of endoscopic lung volume reduction by valves in severe emphysema].

    Science.gov (United States)

    Bocquillon, V; Briault, A; Reymond, E; Arbib, F; Jankowski, A; Ferretti, G; Pison, C

    2016-11-01

    In severe emphysema, endoscopic lung volume reduction with valves is an alternative to surgery with less morbidity and mortality. In 2015, selection of patients who will respond to this technique is based on emphysema heterogeneity, a complete fissure visible on the CT-scan and absence of collateral ventilation between lobes. Our case report highlights that individualized prediction is possible. A 58-year-old woman had severe, disabling pulmonary emphysema. A high resolution thoracic computed tomography scan showed that the emphysema was heterogeneous, predominantly in the upper lobes, integrity of the left greater fissure and no collateral ventilation with the left lower lobe. A valve was inserted in the left upper lobe bronchus. At one year, clinical and functional benefits were significant with complete atelectasis of the treated lobe. The success of endoscopic lung volume reduction with a valve can be predicted, an example of personalized medicine. Copyright © 2016 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  4. Determination of peripheral underdosage at the lung-tumor interface using Monte Carlo radiation transport calculations

    International Nuclear Information System (INIS)

    Taylor, Michael; Dunn, Leon; Kron, Tomas; Height, Felicity; Franich, Rick

    2012-01-01

    Prediction of dose distributions in close proximity to interfaces is difficult. In the context of radiotherapy of lung tumors, this may affect the minimum dose received by lesions and is particularly important when prescribing dose to covering isodoses. The objective of this work is to quantify underdosage in key regions around a hypothetical target using Monte Carlo dose calculation methods, and to develop a factor for clinical estimation of such underdosage. A systematic set of calculations are undertaken using 2 Monte Carlo radiation transport codes (EGSnrc and GEANT4). Discrepancies in dose are determined for a number of parameters, including beam energy, tumor size, field size, and distance from chest wall. Calculations were performed for 1-mm 3 regions at proximal, distal, and lateral aspects of a spherical tumor, determined for a 6-MV and a 15-MV photon beam. The simulations indicate regions of tumor underdose at the tumor-lung interface. Results are presented as ratios of the dose at key peripheral regions to the dose at the center of the tumor, a point at which the treatment planning system (TPS) predicts the dose more reliably. Comparison with TPS data (pencil-beam convolution) indicates such underdosage would not have been predicted accurately in the clinic. We define a dose reduction factor (DRF) as the average of the dose in the periphery in the 6 cardinal directions divided by the central dose in the target, the mean of which is 0.97 and 0.95 for a 6-MV and 15-MV beam, respectively. The DRF can assist clinicians in the estimation of the magnitude of potential discrepancies between prescribed and delivered dose distributions as a function of tumor size and location. Calculation for a systematic set of “generic” tumors allows application to many classes of patient case, and is particularly useful for interpreting clinical trial data.

  5. Determination of peripheral underdosage at the lung-tumor interface using Monte Carlo radiation transport calculations

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Michael, E-mail: michael.taylor@rmit.edu.au [School of Applied Sciences, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria (Australia); Physical Sciences, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia); Dunn, Leon; Kron, Tomas; Height, Felicity; Franich, Rick [School of Applied Sciences, College of Science, Engineering and Health, RMIT University, Melbourne, Victoria (Australia); Physical Sciences, Peter MacCallum Cancer Centre, East Melbourne, Victoria (Australia)

    2012-04-01

    Prediction of dose distributions in close proximity to interfaces is difficult. In the context of radiotherapy of lung tumors, this may affect the minimum dose received by lesions and is particularly important when prescribing dose to covering isodoses. The objective of this work is to quantify underdosage in key regions around a hypothetical target using Monte Carlo dose calculation methods, and to develop a factor for clinical estimation of such underdosage. A systematic set of calculations are undertaken using 2 Monte Carlo radiation transport codes (EGSnrc and GEANT4). Discrepancies in dose are determined for a number of parameters, including beam energy, tumor size, field size, and distance from chest wall. Calculations were performed for 1-mm{sup 3} regions at proximal, distal, and lateral aspects of a spherical tumor, determined for a 6-MV and a 15-MV photon beam. The simulations indicate regions of tumor underdose at the tumor-lung interface. Results are presented as ratios of the dose at key peripheral regions to the dose at the center of the tumor, a point at which the treatment planning system (TPS) predicts the dose more reliably. Comparison with TPS data (pencil-beam convolution) indicates such underdosage would not have been predicted accurately in the clinic. We define a dose reduction factor (DRF) as the average of the dose in the periphery in the 6 cardinal directions divided by the central dose in the target, the mean of which is 0.97 and 0.95 for a 6-MV and 15-MV beam, respectively. The DRF can assist clinicians in the estimation of the magnitude of potential discrepancies between prescribed and delivered dose distributions as a function of tumor size and location. Calculation for a systematic set of 'generic' tumors allows application to many classes of patient case, and is particularly useful for interpreting clinical trial data.

  6. Effect of different seated positions on lung volume and oxygenation in acute respiratory distress syndrome.

    Science.gov (United States)

    Dellamonica, J; Lerolle, N; Sargentini, C; Hubert, S; Beduneau, G; Di Marco, F; Mercat, A; Diehl, J L; Richard, J C M; Bernardin, G; Brochard, L

    2013-06-01

    Lung volume available for ventilation is markedly decreased during acute respiratory distress syndrome. Body positioning may contribute to increase lung volume and partial verticalization is simple to perform. This study evaluated whether verticalization had parallel effects on oxygenation and end expiratory lung volume (EELV). Prospective multicenter study in 40 mechanically ventilated patients with ALI/ARDS in five university hospital MICUs. We evaluated four 45-min successive trunk position epochs (supine slightly elevated at 15°; semi recumbent with trunk elevated at 45°; seated with trunk elevated at 60° and legs down at 45°; back to supine). Arterial blood gases, EELV measured using the nitrogen washin/washout, and static compliance were measured. Responders were defined by a PaO₂/FiO₂ increase >20 % between supine and seated position. Results are median [25th-75th percentiles]. With median PEEP = 10 cmH₂O, verticalization increased lung volume but only responders (13 patients, 32 %) had a significant increase in EELV/PBW (predicted body weight) compared to baseline. This increase persisted at least partially when patients were positioned back to supine. Responders had a lower EELV/PBW supine [14 mL/kg (13-15) vs. 18 mL/kg (15-27) (p = 0.005)] and a lower compliance [30 mL/cmH₂O (22-38) vs. 42 (30-46) (p = 0.01)] than non-responders. Strain decreased with verticalization for responders. EELV/PBW increase and PaO₂/FiO₂ increase were not correlated. Verticalization is easily achieved and improves oxygenation in approximately 32 % of the patients together with an increase in EELV. Nonetheless, effect of verticalization on EELV/PBW is not predictable by PaO₂/FiO₂ increase, its monitoring may be helpful for strain optimization.

  7. Evaluation of patients undergoing lung volume reduction surgery: Ancillary information available from computed tomography

    International Nuclear Information System (INIS)

    Cleverley, Joanne R.; Desai, Sujal R.; Wells, Athol U.; Koyama, Hiroshi; Eastick, Sian; Schmidt, Maria A.; Charrier, Clare L.; Gatehouse, Peter D.; Goldstraw, Peter; Pepper, John R.; Geddes, Duncan M.; Hansell, David M.

    2000-01-01

    AIM: A number of imaging techniques have been used for the pre-operative assessment of patients for lung volume reduction surgery (LVRS). We evaluated whether data currently acquired from perfusion scintigrams and cine MR of the diaphragm are obtainable from high resolution CT (HRCT) of the thorax. MATERIALS AND METHODS: Thirty patients taking part in a randomized controlled trial of LVRS against maximal medical therapy were evaluated. HRCT examinations (n= 30) were scored for (i) the extent and distribution of emphysema; (ii) the extent of normal pulmonary vasculature; and (iii) diaphragmatic contour, apparent defects and herniation. On scintigraphy, (n28), perfusion of the lower thirds of both lungs, as a proportion of total lung perfusion (LZ/T PERF ), was expressed as a percentage of predicted values (derived from 10 normal control subjects). On cine MR (n= 25) hemidiaphragmatic excursion and coordination were recorded. RESULTS: Extensive emphysema was present on HRCT (60% ± 13.2%). There was strong correlation between the extent of normal pulmonary vasculature on HRCT and on perfusion scanning (r s = 0.85, P< 0.00005). Hemidiaphragmatic incoordination on MR was weakly associated with hemidiaphragmatic eventration on HRCT (P0.04). CONCLUSION: The strong correlation between lung perfusion assessed by HRCT and lung perfusion on scintigraphy suggests that perfusion scintigraphy is superfluous in the pre-operative evaluation of patients with emphysema for LVRS. Cleverley, J.R. (2000)

  8. [Treatment of acute respiratory distress syndrome using pressure and volume controlled ventilation with lung protective strategy].

    Science.gov (United States)

    Ge, Ying; Wan, Yong; Wang, Da-qing; Su, Xiao-lin; Li, Jun-ying; Chen, Jing

    2004-07-01

    To investigate the significance and effect of pressure controlled ventilation (PCV) as well as volume controlled ventilation (VCV) by lung protective strategy on respiratory mechanics, blood gas analysis and hemodynamics in patients with acute respiratory distress syndrome (ARDS). Fifty patients with ARDS were randomly divided into PCV and VCV groups with permissive hypercapnia and open lung strategy. Changes in respiratory mechanics, blood gas analysis and hemodynamics were compared between two groups. Peak inspiration pressure (PIP) in PCV group was significantly lower than that in VCV group, while mean pressure of airway (MPaw) was significantly higher than that in VCV after 24 hours mechanical ventilation. After 24 hours mechanical ventilation, there were higher central venous pressure (CVP) and slower heart rate (HR) in two groups, CVP was significantly higher in VCV compared with PCV, and PCV group had slower HR than VCV group, the two groups had no differences in mean blood pressure (MBP) at various intervals. All patients showed no ventilator-induced lung injury. Arterial blood oxygenations were obviously improved in two groups after 24 hours mechanical ventilation, PCV group had better partial pressure of oxygen in artery (PaO2) than VCV group. Both PCV and VCV can improve arterial blood oxygenations, prevent ventilator-induced lung injury, and have less disturbance in hemodynamic parameters. PCV with lung protective ventilatory strategy should be early use for patients with ARDS.

  9. Volume-Targeted Ventilation in the Neonate: Benchmarking Ventilators on an Active Lung Model.

    Science.gov (United States)

    Krieger, Tobias J; Wald, Martin

    2017-03-01

    Mechanically ventilated neonates have been observed to receive substantially different ventilation after switching ventilator models, despite identical ventilator settings. This study aims at establishing the range of output variability among 10 neonatal ventilators under various breathing conditions. Relative benchmarking test of 10 neonatal ventilators on an active neonatal lung model. Neonatal ICU. Ten current neonatal ventilators. Ventilators were set identically to flow-triggered, synchronized, volume-targeted, pressure-controlled, continuous mandatory ventilation and connected to a neonatal lung model. The latter was configured to simulate three patients (500, 1,500, and 3,500 g) in three breathing modes each (passive breathing, constant active breathing, and variable active breathing). Averaged across all weight conditions, the included ventilators delivered between 86% and 110% of the target tidal volume in the passive mode, between 88% and 126% during constant active breathing, and between 86% and 120% under variable active breathing. The largest relative deviation occurred during the 500 g constant active condition, where the highest output machine produced 147% of the tidal volume of the lowest output machine. All machines deviate significantly in volume output and ventilation regulation. These differences depend on ventilation type, respiratory force, and patient behavior, preventing the creation of a simple conversion table between ventilator models. Universal neonatal tidal volume targets for mechanical ventilation cannot be transferred from one ventilator to another without considering necessary adjustments.

  10. Clinical and radiological outcome following pneumothorax after endoscopic lung volume reduction with valves.

    Science.gov (United States)

    Gompelmann, D; Benjamin, N; Kontogianni, K; Herth, Fjf; Heussel, C P; Hoffmann, H; Eberhardt, R

    2016-01-01

    Valve implantation has evolved as a therapy for patients with advanced emphysema. Although it is a minimally invasive treatment, it is associated with complications, the most common being pneumothorax. Pneumothorax occurs due to the rapid target lobe volume reduction and may be a predictor of clinical benefit despite this complication. The objective of this study was to conduct an exploratory data analysis of patients who developed a pneumothorax following endoscopic valve therapy for emphysema. This study performed a retrospective evaluation of pneumothorax management and the impact of pneumothorax on clinical outcomes in 70 patients following valve therapy in 381 consecutive patients. Pneumothorax rate following valve therapy was 18%. Pneumothorax management consisted of chest tube insertion, valve removal, and surgical intervention in 87% (61/70), 44% (31/70), and 19% (13/70) of the patients, respectively. Despite pneumothorax, patients experienced modest but significant improvements in lung function parameters (forced expiratory volume in 1 second: 55±148 mL, residual volume: -390±964 mL, total lung capacity: -348±876; all P pneumothorax, which was associated with relevant clinical improvement, was observed in only 21% (15/70) of the patients. Pneumothorax is a frequent severe complication following valve therapy that requires further intervention. Nevertheless, the pneumothorax does not impair the clinical status in the majority of patients. Patients with lobar atelectasis benefit after recovering from pneumothorax in terms of lung function parameters.

  11. Dosimetric accuracy and clinical quality of Acuros XB and AAA dose calculation algorithm for stereotactic and conventional lung volumetric modulated arc therapy plans

    International Nuclear Information System (INIS)

    Kroon, Petra S; Hol, Sandra; Essers, Marion

    2013-01-01

    The main aim of the current study was to assess the dosimetric accuracy and clinical quality of volumetric modulated arc therapy (VMAT) plans for stereotactic (stage I) and conventional (stage III) lung cancer treatments planned with Eclipse version 10.0 Anisotropic Analytical Algorithm (AAA) and Acuros XB (AXB) algorithm. The dosimetric impact of using AAA instead of AXB, and grid size 2.5 mm instead of 1.0 mm for VMAT treatment plans was evaluated. The clinical plan quality of AXB VMAT was assessed using 45 stage I and 73 stage III patients, and was compared with published results, planned with VMAT and hybrid-VMAT techniques. The dosimetric impact on near-minimum PTV dose (D 98% ) using AAA instead of AXB was large (underdose up to 12.3%) for stage I and very small (underdose up to 0.8%) for stage III lung treatments. There were no significant differences for dose volume histogram (DVH) values between grid sizes. The calculation time was significantly higher for AXB grid size 1.0 than 2.5 mm (p < 0.01). The clinical quality of the VMAT plans was at least comparable with clinical qualities given in literature of lung treatment plans with VMAT and hybrid-VMAT techniques. The average mean lung dose (MLD), lung V 20Gy and V 5Gy in this study were respectively 3.6 Gy, 4.1% and 15.7% for 45 stage I patients and 12.4 Gy, 19.3% and 46.6% for 73 stage III lung patients. The average contra-lateral lung dose V 5Gy-cont was 35.6% for stage III patients. For stereotactic and conventional lung treatments, VMAT calculated with AXB grid size 2.5 mm resulted in accurate dose calculations. No hybrid technique was needed to obtain the dose constraints. AXB is recommended instead of AAA for avoiding serious overestimation of the minimum target doses compared to the actual delivered dose

  12. Lung Volume Reduction Coil Treatment in Chronic Obstructive Pulmonary Disease Patients with Homogeneous Emphysema : A Prospective Feasibility Trial

    NARCIS (Netherlands)

    Klooster, Karin; ten Hacken, Nick H. T.; Franz, Ina; Kerstjens, Huib A. M.; van Rikxoort, Eva M.; Slebos, Dirk-Jan

    2014-01-01

    Background: In patients with heterogeneous emphysema, surgical and bronchoscopic lung volume reduction (LVR) treatments are available. However, for patients with homogeneous emphysema these treatments are hardly investigated and seem less effective. Bronchoscopic LVR coil treatment has been shown to

  13. Bronchoscopic lung-volume reduction with Exhale airway stents for emphysema (EASE trial) : randomised, sham-controlled, multicentre trial

    NARCIS (Netherlands)

    Shah, P. L.; Slebos, D-J; Cardoso, P. F. G.; Cetti, E.; Voelker, K.; Levine, B.; Russell, M. E.; Goldin, J.; Brown, M.; Cooper, J. D.; Sybrecht, G. W.

    2011-01-01

    Background Airway bypass is a bronchoscopic lung-volume reduction procedure for emphysema whereby transbronchial passages into the lung are created to release trapped air, supported with paclitaxel-coated stents to ease the mechanics of breathing. The aim of the EASE (Exhale airway stents for

  14. Slope excavation quality assessment and excavated volume calculation in hydraulic projects based on laser scanning technology

    Directory of Open Access Journals (Sweden)

    Chao Hu

    2015-04-01

    Full Text Available Slope excavation is one of the most crucial steps in the construction of a hydraulic project. Excavation project quality assessment and excavated volume calculation are critical in construction management. The positioning of excavation projects using traditional instruments is inefficient and may cause error. To improve the efficiency and precision of calculation and assessment, three-dimensional laser scanning technology was used for slope excavation quality assessment. An efficient data acquisition, processing, and management workflow was presented in this study. Based on the quality control indices, including the average gradient, slope toe elevation, and overbreak and underbreak, cross-sectional quality assessment and holistic quality assessment methods were proposed to assess the slope excavation quality with laser-scanned data. An algorithm was also presented to calculate the excavated volume with laser-scanned data. A field application and a laboratory experiment were carried out to verify the feasibility of these methods for excavation quality assessment and excavated volume calculation. The results show that the quality assessment indices can be obtained rapidly and accurately with design parameters and scanned data, and the results of holistic quality assessment are consistent with those of cross-sectional quality assessment. In addition, the time consumption in excavation quality assessment with the laser scanning technology can be reduced by 70%–90%, as compared with the traditional method. The excavated volume calculated with the scanned data only slightly differs from measured data, demonstrating the applicability of the excavated volume calculation method presented in this study.

  15. Does early tetralogy of Fallot total correction give better final lung volumes?

    Science.gov (United States)

    Sadeghi, Hasan Allah; Miri, Seyed Reza; Bakhshandeh, Hooman; Mirmesdagh, Yalda; Paziraee, Nazita

    2013-06-01

    Pulmonary blood flow may affect lung development in adulthood. Early total correction of tetralogy of Fallot may affect development of final lung volumes. We evaluated the effect of age at total correction on lung volumes years after the operation. In a retrospective cohort study on patients with totally corrected tetralogy of Fallot (mean age, 13.40 years at the time of follow-up), forced vital capacity, slow vital capacity, forced expiratory volume in 1 s, and other parameters were measured 154.8 ± 46.25 months after the operation. Comparison were made of 3 groups: ≤2-, 2-8-, and >8-years old at the time of total correction surgery. Among 322 enrolled patients, the mean values of the follow-up spirometry results in ≤2-, 2-8-, >8-year-olds and the percentage of predicted values were respectively: vital capacity: 4.46 ± 0.57 L (107% ± 10.96%), 3.89 ± 0.58 L (91.10% ± 12.25%), 3.25 ± 0.48 L (82.35% ± 10.62%), p volume in 1 s: 4.22 ± 0.63 L (104.84% ± 13.64%), 3.66 ± 0.58 L (90.61% ± 12.59%), 3.02 ± 0.48 L (84.31% ± 12%), p volumes and capacities. It is better to consider total correction for all tetralogy of Fallot patients below 2-years old, or at least below 8-years old, if it is technically possible.

  16. Quantification of Tumor Volume Changes During Radiotherapy for Non-Small-Cell Lung Cancer

    International Nuclear Information System (INIS)

    Fox, Jana; Ford, Eric; Redmond, Kristin; Zhou, Jessica; Wong, John; Song, Danny Y.

    2009-01-01

    Purpose: Dose escalation for lung cancer is limited by normal tissue toxicity. We evaluated sequential computed tomography (CT) scans to assess the possibility of adaptively reducing treatment volumes by quantifying the tumor volume reduction occurring during a course of radiotherapy (RT). Methods and Materials: A total of 22 patients underwent RT for Stage I-III non-small-cell lung cancer with conventional fractionation; 15 received concurrent chemotherapy. Two repeat CT scans were performed at a nominal dose of 30 Gy and 50 Gy. Respiration-correlated four-dimensional CT scans were used for evaluation of respiratory effects in 17 patients. The gross tumor volume (GTV) was delineated on simulation and all individual phases of the repeat CT scans. Parenchymal tumor was evaluated unless the nodal volume was larger or was the primary. Subsequent image sets were spatially co-registered with the simulation data for evaluation. Results: The median GTV reduction was 24.7% (range, -0.3% to 61.7%; p 100 cm 3 vs. 3 , and hilar and/or mediastinal involvement vs. purely parenchymal or pleural lesions. A tendency toward a greater volume reduction with increasing dose was seen, although this did not reach statistical significance. Conclusion: The results of this study have demonstrated significant alterations in the GTV seen on repeat CT scans during RT. These observations raise the possibility of using an adaptive approach toward RT of non-small-cell lung cancer to minimize the dose to normal structures and more safely increase the dose directed at the target tissues.

  17. Calculating the tumor volume of acoustic neuromas: comparison of ABC/2 formula with planimetry method.

    Science.gov (United States)

    Yu, Yi-Lin; Lee, Meei-Shyuan; Juan, Chun-Jung; Hueng, Dueng-Yuan

    2013-08-01

    The ABC/2 equation is commonly applied to measure the volume of intracranial hematoma. However, the precision of ABC/2 equation in estimating the tumor volume of acoustic neuromas is less addressed. The study is to evaluate the accuracy of the ABC/2 formula by comparing with planimetry method for estimating the tumor volumes. Thirty-two patients diagnosed with acoustic neuroma received contrast-enhanced magnetic resonance imaging of brain were recruited. The volume was calculated by the ABC/2 equation and planimetry method (defined as exact volume) at the same time. The 32 patients were divided into three groups by tumor volume to avoid volume-dependent overestimation (6 ml). The tumor volume by ABC/2 method was highly correlated to that calculated by planimetry method using linear regression analysis (R2=0.985). Pearson correlation coefficient (r=0.993, pABC/2 formula is an easy method in estimating the tumor volume of acoustic neuromas that is not inferior to planimetry method. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Growth Patterns of Fetal Lung Volumes in Healthy Fetuses and Fetuses With Isolated Left-Sided Congenital Diaphragmatic Hernia.

    Science.gov (United States)

    Ruano, Rodrigo; Britto, Ingrid Schwach Werneck; Sananes, Nicolas; Lee, Wesley; Sangi-Haghpeykar, Haleh; Deter, Russell L

    2016-06-01

    To evaluate fetal lung growth using 3-dimensional sonography in healthy fetuses and those with congenital diaphragmatic hernia (CDH). Right and total lung volumes were serially evaluated by 3-dimensional sonography in 66 healthy fetuses and 52 fetuses with left-sided CDH between 20 and 37 weeks' menstrual age. Functions fitted to these parameters were compared for 2 groups: (1) healthy versus those with CDH; and (2) fetuses with CHD who survived versus those who died. Fetal right and total lung volumes as well as fetal observed-to-expected right and total lung volume ratios were significantly lower in fetuses with CDH than healthy fetuses (Pvolume ratios did not vary with menstrual age in healthy fetuses or in those with CDH (independent of outcome). Lung volume rates were lower in fetuses with left-sided CDH compared to healthy fetuses, as well as in fetuses with CDH who died compared to those who survived. The observed-to-expected right and total lung volume ratios were relatively constant throughout menstrual age in fetuses with left-sided CDH, suggesting that the origin of their lung growth abnormalities occurred before 20 weeks and did not progress. The observed-to-expected ratios may be useful in predicting the outcome in fetuses with CDH independent of menstrual age. © 2016 by the American Institute of Ultrasound in Medicine.

  19. Relation of exercise capacity with lung volumes before and after 6-minute walk test in subjects with COPD.

    Science.gov (United States)

    Wibmer, Thomas; Rüdiger, Stefan; Kropf-Sanchen, Cornelia; Stoiber, Kathrin M; Rottbauer, Wolfgang; Schumann, Christian

    2014-11-01

    There is growing evidence that exercise-induced variation in lung volumes is an important source of ventilatory limitation and is linked to exercise intolerance in COPD. The aim of this study was to compare the correlations of walk distance and lung volumes measured before and after a 6-min walk test (6MWT) in subjects with COPD. Forty-five subjects with stable COPD (mean pre-bronchodilator FEV1: 47 ± 18% predicted) underwent a 6MWT. Body plethysmography was performed immediately pre- and post-6MWT. Correlations were generally stronger between 6-min walk distance and post-6MWT lung volumes than between 6-min walk distance and pre-6MWT lung volumes, except for FEV1. These differences in Pearson correlation coefficients were significant for residual volume expressed as percent of total lung capacity (-0.67 vs -0.58, P = .043), percent of predicted residual volume expressed as percent of total lung capacity (-0.68 vs -0.59, P = .026), inspiratory vital capacity (0.65 vs 0.54, P = .019), percent of predicted inspiratory vital capacity (0.49 vs 0.38, P = .037), and percent of predicted functional residual capacity (-0.62 vs -0.47, P = .023). In subjects with stable COPD, lung volumes measured immediately after 6MWT are more closely related to exercise limitation than baseline lung volumes measured before 6MWT, except for FEV1. Therefore, pulmonary function testing immediately after exercise should be included in future studies on COPD for the assessment of exercise-induced ventilatory constraints to physical performance that cannot be adequately assessed from baseline pulmonary function testing at rest. Copyright © 2014 by Daedalus Enterprises.

  20. Combined use of positron emission tomography and volume doubling time in lung cancer screening with low-dose CT scanning

    DEFF Research Database (Denmark)

    Ashraf, H; Dirksen, A; Jakobsen, Annika Loft

    2011-01-01

    In lung cancer screening the ability to distinguish malignant from benign nodules is a key issue. This study evaluates the ability of positron emission tomography (PET) and volume doubling time (VDT) to discriminate between benign and malignant nodules.......In lung cancer screening the ability to distinguish malignant from benign nodules is a key issue. This study evaluates the ability of positron emission tomography (PET) and volume doubling time (VDT) to discriminate between benign and malignant nodules....

  1. The Impact of Heart Irradiation on Dose-Volume Effects in the Rat Lung

    International Nuclear Information System (INIS)

    Luijk, Peter van; Faber, Hette; Meertens, Harm; Schippers, Jacobus M.; Langendijk, Johannes A.; Brandenburg, Sytze; Kampinga, Harm H.; Coppes, Robert P. Ph.D.

    2007-01-01

    Purpose: To test the hypothesis that heart irradiation increases the risk of a symptomatic radiation-induced loss of lung function (SRILF) and that this can be well-described as a modulation of the functional reserve of the lung. Methods and Materials: Rats were irradiated with 150-MeV protons. Dose-response curves were obtained for a significant increase in breathing frequency after irradiation of 100%, 75%, 50%, or 25% of the total lung volume, either including or excluding the heart from the irradiation field. A significant increase in the mean respiratory rate after 6-12 weeks compared with 0-4 weeks was defined as SRILF, based on biweekly measurements of the respiratory rate. The critical volume (CV) model was used to describe the risk of SRILF. Fits were done using a maximum likelihood method. Consistency between model and data was tested using a previously developed goodness-of-fit test. Results: The CV model could be fitted consistently to the data for lung irradiation only. However, this fitted model failed to predict the data that also included heart irradiation. Even refitting the model to all data resulted in a significant difference between model and data. These results imply that, although the CV model describes the risk of SRILF when the heart is spared, the model needs to be modified to account for the impact of dose to the heart on the risk of SRILF. Finally, a modified CV model is described that is consistent to all data. Conclusions: The detrimental effect of dose to the heart on the incidence of SRILF can be described by a dose dependent decrease in functional reserve of the lung

  2. Effects of tidal volume on work of breathing during lung-protective ventilation in patients with acute lung injury and acute respiratory distress syndrome.

    Science.gov (United States)

    Kallet, Richard H; Campbell, Andre R; Dicker, Rochelle A; Katz, Jeffrey A; Mackersie, Robert C

    2006-01-01

    To assess the effects of step-changes in tidal volume on work of breathing during lung-protective ventilation in patients with acute lung injury (ALI) or the acute respiratory distress syndrome (ARDS). Prospective, nonconsecutive patients with ALI/ARDS. Adult surgical, trauma, and medical intensive care units at a major inner-city, university-affiliated hospital. Ten patients with ALI/ARDS managed clinically with lung-protective ventilation. Five patients were ventilated at a progressively smaller tidal volume in 1 mL/kg steps between 8 and 5 mL/kg; five other patients were ventilated at a progressively larger tidal volume from 5 to 8 mL/kg. The volume mode was used with a flow rate of 75 L/min. Minute ventilation was maintained constant at each tidal volume setting. Afterward, patients were placed on continuous positive airway pressure for 1-2 mins to measure their spontaneous tidal volume. Work of breathing and other variables were measured with a pulmonary mechanics monitor (Bicore CP-100). Work of breathing progressively increased (0.86 +/- 0.32, 1.05 +/- 0.40, 1.22 +/- 0.36, and 1.57 +/- 0.43 J/L) at a tidal volume of 8, 7, 6, and 5 mL/kg, respectively. In nine of ten patients there was a strong negative correlation between work of breathing and the ventilator-to-patient tidal volume difference (R = -.75 to -.998). : The ventilator-delivered tidal volume exerts an independent influence on work of breathing during lung-protective ventilation in patients with ALI/ARDS. Patient work of breathing is inversely related to the difference between the ventilator-delivered tidal volume and patient-generated tidal volume during a brief trial of unassisted breathing.

  3. Comparison of the accuracy of three angiographic methods for calculating left ventricular volume measurement

    International Nuclear Information System (INIS)

    Hu Lin; Cui Wei; Shi Hanwen; Tian Yingping; Wang Weigang; Feng Yanguang; Huang Xueyan; Liu Zhisheng

    2003-01-01

    Objective: To compare the relative accuracy of three methods measuring left ventricular volume by X-ray ventriculography: single plane area-length method, biplane area-length method, and single-plane Simpson's method. Methods: Left ventricular casts were obtained within 24 hours after death from 12 persons who died from non-cardiac causes. The true left ventricular cast volume was measured by water displacement. The calculated volume of the casts was obtained with 3 angiographic methods, i.e., single-plane area-length method, biplane area-length method, and single-plane Simpson's method. Results: The actual average volume of left ventricular casts was (61.17±26.49) ml. The left ventricular volume was averagely (97.50±35.56) ml with single plane area-length method, (90.51±36.33) ml with biplane area-length method, and (65.00± 23.63) ml with single-plane Simpson's method. The left ventricular volumes calculated with single-plane and biplane area-length method were significantly larger than that the actual volumes (P 0.05). The left ventricular volumes calculated with single-plane and biplane area-length method were significantly larger than those calculated with single-plane Simpson's method (P 0.05). The over-estimation of left ventricular volume by single plane area-length method (36.34±17.98) ml and biplane area-length method (29.34±15.59) ml was more obvious than that calculated by single-plane Simpson's method (3.83±8.48) ml. Linear regression analysis showed that there was close correlations between left ventricular volumes calculated with single plane area-length method, biplane area-length method, Simpson's method and the true volume (all r>0.98). Conclusion: Single-plane Simpson's method is more accurate than single plane area-length method and biplane area-length method for left ventricular volume measurement; however, both the single-plane and biplane area-length methods could be used in clinical practice, especially in those imaging modality

  4. Lung and chest wall impedances in the dog: effects of frequency and tidal volume.

    Science.gov (United States)

    Barnas, G M; Stamenović, D; Lutchen, K R; Mackenzie, C F

    1992-01-01

    Dependences of the mechanical properties of the respiratory system on frequency (f) and tidal volume (VT) in the normal ranges of breathing are not clear. We measured, simultaneously and in vivo, resistance and elastance of the total respiratory system (Rrs and Ers), lungs (RL and EL), and chest wall (Rcw and Ecw) of five healthy anesthetized paralyzed dogs during sinusoidal volume oscillations at the trachea (50-300 ml, 0.2-2 Hz) delivered at a constant mean lung volume. Each dog showed the same f and VT dependences. The Ers and Ecw increased with increasing f to 1 Hz and decreased with increasing VT up to 200 ml. Although EL increased slightly with increasing f, it was independent of VT. The Rcw decreased from 0.2 to 2 Hz at all VT and decreased with increasing VT. Although the RL decreased from 0.2 to 0.6 Hz and was independent of VT, at higher f RL tended to increase with increasing f and VT (i.e., as peak flow increased). Finally, the f and VT dependences of Rrs were similar to those of Rcw below 0.6 Hz but mirrored RL at higher f. These data capture the competing influences of airflow nonlinearities vs. tissue nonlinearities on f and VT dependence of the lung, chest wall, and total respiratory system. More specifically, we conclude that 1) VT dependences in Ers and Rrs below 0.6 Hz are due to nonlinearities in chest wall properties, 2) above 0.6 Hz, the flow dependence of airways resistance dominates RL and Rrs, and 3) lung tissue behavior is linear in the normal range of breathing.

  5. Clinical utility of computed tomographic lung volumes in patients with chronic obstructive pulmonary disease.

    Science.gov (United States)

    Lee, Jae Seung; Lee, Sang-Min; Seo, Joon Beom; Lee, Sei Won; Huh, Jin Won; Oh, Yeon-Mok; Lee, Sang-Do

    2014-01-01

    Published data concerning the utility of computed tomography (CT)-based lung volumes are limited to correlation with lung function. The aim of this study was to evaluate the clinical utility of the CT expiratory-to-inspiratory lung volume ratio (CT Vratio) by assessing the relationship with clinically relevant outcomes. A total of 75 stable chronic obstructive pulmonary disease (COPD) patients having pulmonary function testing and volumetric CT at full inspiration and expiration were retrospectively evaluated. Inspiratory and expiratory CT lung volumes were measured using in-house software. Correlation of the CT Vratio with patient-centered outcomes, including the modified Medical Research Council (MMRC) dyspnea score, the 6-min walk distance (6MWD), the St. George's Respiratory Questionnaire (SGRQ) score, and multidimensional COPD severity indices, such as the BMI, airflow obstruction, dyspnea, and exercise capacity index (BODE) and age, dyspnea, and airflow obstruction (ADO), were analyzed. The CT Vratio correlated significantly with BMI (r = -0.528, p < 0.001). The CT Vratio was also significantly associated with MMRC dyspnea (r = 0.387, p = 0.001), 6MWD (r = -0.459, p < 0.001), and SGRQ (r = 0.369, p = 0.001) scores. Finally, the CT Vratio had significant correlations with the BODE and ADO multidimensional COPD severity indices (r = 0.605, p < 0.001; r = 0.411, p < 0.001). The CT Vratio had significant correlations with patient-centered outcomes and multidimensional COPD severity indices. © 2013 S. Karger AG, Basel.

  6. Static lung volume should be used to confirm restrictive lung disease

    Directory of Open Access Journals (Sweden)

    Rasam SA

    2016-09-01

    Full Text Available Shweta A Rasam, Nitin V Vanjare Department of Pulmonary Function Laboratory, Chest Research Foundation, Pune, Maharashtra, IndiaWe read the study by Hee Jin Park et al1 with great interest. The authors have investigated the prevalence of comorbidities in Korean chronic obstructive pulmonary disease (COPD population. We raise our concern regarding the definition of COPD in this study. The study defines COPD as airflow limitation (only pre-spirometry forced expiratory volume in 1 second/forced vital capacity [FEV1/FVC] <70% in subjects aged ≥40 years. To differentiate, between asthma and COPD, it is essential to do a post bronchodilator spirometry. It would have been wise to report the findings as prevalence of comorbidities in obstructive airway diseases rather than specifically calling it as COPD.View original paper by Park and colleagues.

  7. Cone-Beam CT Localization of Internal Target Volumes for Stereotactic Body Radiotherapy of Lung Lesions

    International Nuclear Information System (INIS)

    Wang Zhiheng; Wu, Q. Jackie; Marks, Lawrence B.; Larrier, Nicole; Yin Fangfang

    2007-01-01

    Purpose: In this study, we investigate a technique of matching internal target volumes (ITVs) in four-dimensional (4D) simulation computed tomography (CT) to the composite target volume in free-breathing on-board cone-beam (CB) CT. The technique is illustrated by using both phantom and patient cases. Methods and Materials: A dynamic phantom with a target ball simulating respiratory motion with various amplitude and cycle times was used to verify localization accuracy. The dynamic phantom was scanned using simulation CT with a phase-based retrospective sorting technique. The ITV was then determined based on 10 sets of sorted images. The size and epicenter of the ITV identified from 4D simulation CT images and the composite target volume identified from on-board CBCT images were compared to assess localization accuracy. Similarly, for two clinical cases of patients with lung cancer, ITVs defined from 4D simulation CT images and CBCT images were compared. Results: For the phantom, localization accuracy between the ITV in 4D simulation CT and the composite target volume in CBCT was within 1 mm, and ITV was within 8.7%. For patient cases, ITVs on simulation CT and CBCT were within 8.0%. Conclusion: This study shows that CBCT is a useful tool to localize ITV for targets affected by respiratory motion. Verification of the ITV from 4D simulation CT using on-board free-breathing CBCT is feasible for the target localization of lung tumors

  8. Evaluation of a new software tool for the automatic volume calculation of hepatic tumors. First results

    International Nuclear Information System (INIS)

    Meier, S.; Mildenberger, P.; Pitton, M.; Thelen, M.; Schenk, A.; Bourquain, H.

    2004-01-01

    Purpose: computed tomography has become the preferred method in detecting liver carcinomas. The introduction of spiral CT added volumetric assessment of intrahepatic tumors, which was unattainable in the clinical routine with incremental CT due to complex planimetric revisions and excessive computing time. In an ongoing clinical study, a new software tool was tested for the automatic detection of tumor volume and the time needed for this procedure. Materials and methods: we analyzed patients suffering from hepatocellular carcinoma (HCC). All patients underwent treatment with repeated transcatheter chemoembolization of the hepatic arteria. The volumes of the HCC lesions detected in CT were measured with the new software tool in HepaVison (MeVis, Germany). The results were compared with manual planimetric calculation of the volume performed by three independent radiologists. Results: our first results in 16 patients show a correlation between the automatically and the manually calculated volumes (up to a difference of 2 ml) of 96.8%. While the manual method of analyzing the volume of a lesion requires 2.5 minutes on average, the automatic method merely requires about 30 seconds of user interaction time. Conclusion: These preliminary results show a good correlation between automatic and manual calculations of the tumor volume. The new software tool requires less time for accurate determination of the tumor volume and can be applied in the daily clinical routine. (orig.) [de

  9. Calculating regional tissue volume for hyperthermic isolated limb perfusion: Four methods compared.

    Science.gov (United States)

    Cecchin, D; Negri, A; Frigo, A C; Bui, F; Zucchetta, P; Bodanza, V; Gregianin, M; Campana, L G; Rossi, C R; Rastrelli, M

    2016-12-01

    Hyperthermic isolated limb perfusion (HILP) can be performed as an alternative to amputation for soft tissue sarcomas and melanomas of the extremities. Melphalan and tumor necrosis factor-alpha are used at a dosage that depends on the volume of the limb. Regional tissue volume is traditionally measured for the purposes of HILP using water displacement volumetry (WDV). Although this technique is considered the gold standard, it is time-consuming and complicated to implement, especially in obese and elderly patients. The aim of the present study was to compare the different methods described in the literature for calculating regional tissue volume in the HILP setting, and to validate an open source software. We reviewed the charts of 22 patients (11 males and 11 females) who had non-disseminated melanoma with in-transit metastases or sarcoma of the lower limb. We calculated the volume of the limb using four different methods: WDV, tape measurements and segmentation of computed tomography images using Osirix and Oncentra Masterplan softwares. The overall comparison provided a concordance correlation coefficient (CCC) of 0.92 for the calculations of whole limb volume. In particular, when Osirix was compared with Oncentra (validated for volume measures and used in radiotherapy), the concordance was near-perfect for the calculation of the whole limb volume (CCC = 0.99). With methods based on CT the user can choose a reliable plane for segmentation purposes. CT-based methods also provides the opportunity to separate the whole limb volume into defined tissue volumes (cortical bone, fat and water). Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Microstructural Consequences of Blast Lung Injury Characterized with Digital Volume Correlation

    Directory of Open Access Journals (Sweden)

    Hari Arora

    2017-12-01

    Full Text Available This study focuses on microstructural changes that occur within the mammalian lung when subject to blast and how these changes influence strain distributions within the tissue. Shock tube experiments were performed to generate the blast injured specimens (cadaveric Sprague-Dawley rats. Blast overpressures of 100 and 180 kPa were studied. Synchrotron tomography imaging was used to capture volumetric image data of lungs. Specimens were ventilated using a custom-built system to study multiple inflation pressures during each tomography scan. These data enabled the first digital volume correlation (DVC measurements in lung tissue to be performed. Quantitative analysis was performed to describe the damaged architecture of the lung. No clear changes in the microstructure of the tissue morphology were observed due to controlled low- to moderate-level blast exposure. However, significant focal sites of injury were observed using DVC, which allowed the detection of bias and concentration in the patterns of strain level. Morphological analysis corroborated the findings, illustrating that the focal damage caused by a blast can give rise to diffuse influence across the tissue. It is important to characterize the non-instantly fatal doses of blast, given the transient nature of blast lung in the clinical setting. This research has highlighted the need for better understanding of focal injury and its zone of influence (alveolar interdependency and neighboring tissue burden as a result of focal injury. DVC techniques show great promise as a tool to advance this endeavor, providing a new perspective on lung mechanics after blast.

  11. Planimetric determination of lung volume and its significance in the radiological diagnosis of pulmonary emphysema

    International Nuclear Information System (INIS)

    Maurer, H.J.; Bieber, M.

    1983-01-01

    The volume of the lungs of 102 patients with emphysema and of 33 normal individuals, aged between 30 and 79 years, was determined with the use of a digital planimeter from routine chest X-rays in two planes. Contrary to the values obtained by a helium dilution method, the volumes, as determined by planimetry, did not show a linear relationship with age, but showed an increase after the age of 60. This agrees with the results of total body plethysmography, carried out by Amrein et al. The planimetric method of Harris, Pratt and Kilburn is a simple and rapid method for demonstrating, even in the presence of regional ventilatory abnormalities, total volume with sufficient accuracy, which complements and quantifies the radiological diagnosis of emphysema. (orig.) [de

  12. Lung volumes and airway resistance in patients with a possible restrictive pattern on spirometry.

    Science.gov (United States)

    Schultz, Kenia; D'Aquino, Luiz Carlos; Soares, Maria Raquel; Gimenez, Andrea; Pereira, Carlos Alberto de Castro

    2016-01-01

    Many patients with proportional reductions in FVC and FEV1 on spirometry show no reduction in TLC. The aim of this study was to evaluate the role that measuring lung volumes and airway resistance plays in the correct classification of patients with a possible restrictive pattern on spirometry. This was a prospective study involving adults with reduced FVC and FEV1, as well as an FEV1/FV(C) ratio within the predicted range. Restrictive lung disease (RLD) was characterized by TLC below the 5th percentile, as determined by plethysmography. Obstructive lung disease (OLD) was characterized by high specific airway resistance, significant changes in post-bronchodilator FEV1, or an FEF25-75% espirometria não têm CPT reduzida. O objetivo deste estudo foi avaliar o papel da medida dos volumes pulmonares e da resistência das vias aéreas para a classificação correta de pacientes com possível restrição à espirometria. Estudo prospectivo de adultos com CVF e VEF1 reduzidos e relação VEF1/CV(F) na faixa prevista. Distúrbio ventilatório restritivo (DVR) foi definido por CPT espirometria. A obstrução ao fluxo aéreo é comum nesses casos.

  13. Poster - 36: Effect of Planning Target Volume Coverage on the Dose Delivered in Lung Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Dekker, Chris; Wierzbicki, Marcin [McMaster University, Juravinski Cancer Centre (Canada)

    2016-08-15

    Purpose: In lung radiotherapy, breathing motion may be encompassed by contouring the internal target volume (ITV). Remaining uncertainties are included in a geometrical expansion to the planning target volume (PTV). In IMRT, the treatment is then optimized until a desired PTV fraction is covered by the appropriate dose. The resulting beams often carry high fluence in the PTV margin to overcome low lung density and to generate steep dose gradients. During treatment, the high density tumour can enter the PTV margin, potentially increasing target dose. Thus, planning lung IMRT with a reduced PTV dose may still achieve the desired ITV dose during treatment. Methods: A retrospective analysis was carried out with 25 IMRT plans prescribed to 63 Gy in 30 fractions. The plans were re-normalized to cover various fractions of the PTV by different isodose lines. For each case, the isocentre was moved using 125 shifts derived from all 3D combinations of 0 mm, (PTV margin - 1 mm), and PTV margin. After each shift, the dose was recomputed to approximate the delivered dose. Results and Conclusion: Our plans typically cover 95% of the PTV by 95% of the dose. Reducing the PTV covered to 94% did not significantly reduce the delivered ITV doses for (PTV margin - 1 mm) shifts. Target doses were reduced significantly for all other shifts and planning goals studied. Thus, a reduced planning goal will likely deliver the desired target dose as long as the ITV rarely enters the last mm of the PTV margin.

  14. Lung Volume Reduction Surgery for Respiratory Failure in Infants With Bronchopulmonary Dysplasia.

    Science.gov (United States)

    Sohn, Bongyeon; Park, Samina; Park, In Kyu; Kim, Young Tae; Park, June Dong; Park, Sung-Hye; Kang, Chang Hyun

    2018-04-01

    Lung volume reduction surgery (LVRS) can be performed in patients with severe emphysematous disease. However, LVRS in pediatric patients has not yet been reported. Here, we report our experience with 2 cases of pediatric LVRS. The first patient was a preterm infant girl with severe bronchopulmonary dysplasia, pulmonary hypertension, and hypothyroidism. The emphysematous portion of the right lung was removed via sternotomy and right hemiclamshell incision. The patient was discharged on full-time home ventilator support for 3 months after the surgery. Since then, her respiratory function has improved continuously. She no longer needs oxygen supplementation or ventilator care. Her T-cannula was removed recently. The second patient was also a preterm infant girl with bronchopulmonary dysplasia. She was born with pulmonary hypertension and multiple congenital anomalies, including an atrial septal defect. Despite receiving the best supportive care, she could not be taken off the mechanical ventilator because of severe hypercapnia. We performed LVRS on the right lung via thoracotomy. She was successfully weaned off the mechanical ventilator 1 month after the surgery. She was discharged without severe complications at 3 months after the operation. At present, she is growing well with the help of intermittent home ventilator support. She can now tolerate an oral diet. Our experience shows that LVRS can be considered as a treatment option for pediatric patients with severe emphysematous lung. It is especially helpful for discontinuing prolonged mechanical ventilator care for patients with respiratory failure. Copyright © 2018 by the American Academy of Pediatrics.

  15. Obesity disproportionately impacts lung volumes, airflow and exhaled nitric oxide in children.

    Science.gov (United States)

    Yao, Tsung-Chieh; Tsai, Hui-Ju; Chang, Su-Wei; Chung, Ren-Hua; Hsu, Jing-Ya; Tsai, Ming-Han; Liao, Sui-Ling; Hua, Man-Chin; Lai, Shen-Hao; Chen, Li-Chen; Yeh, Kuo-Wei; Tseng, Yu-Lun; Lin, Wan-Chen; Chang, Su-Ching; Huang, Jing-Long

    2017-01-01

    The current literature focusing on the effect of obesity and overweight on lung function and fraction of exhaled nitric oxide (FeNO) in children, particularly among healthy children of non-European descent, remains controversial. Furthermore, whether the relationship of obesity and overweight with lung function and FeNO in children is modified by atopy is unclear. The objective of this study was to examine the effect of excess weight on lung function parameters and FeNO among Asian children, with a particular focus on exploring the potential effect modification by atopy. We investigated the effect of excess weight on lung function and FeNO in a population sample of 1,717 children aged 5 to 18 years and explored the potential modifying effect of atopy. There were positive associations of body mass index (BMI) z-score with forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), peak expiratory flow (PEF), and forced expiratory flow at 25-75% (FEF25-75) (all Pchildren from the general population, independent of atopic status. Excess weight inversely affects FeNO in atopic but not in non-atopic children.

  16. Influence of heart failure on resting lung volumes in patients with COPD

    Science.gov (United States)

    de Souza, Aline Soares; Sperandio, Priscila Abreu; Mazzuco, Adriana; Alencar, Maria Clara; Arbex, Flávio Ferlin; de Oliveira, Mayron Faria; O'Donnell, Denis Eunan; Neder, José Alberto

    2016-01-01

    ABSTRACT Objective: To evaluate the influence of chronic heart failure (CHF) on resting lung volumes in patients with COPD, i.e., inspiratory fraction-inspiratory capacity (IC)/TLC-and relative inspiratory reserve-[1 − (end-inspiratory lung volume/TLC)]. Methods: This was a prospective study involving 56 patients with COPD-24 (23 males/1 female) with COPD+CHF and 32 (28 males/4 females) with COPD only-who, after careful clinical stabilization, underwent spirometry (with forced and slow maneuvers) and whole-body plethysmography. Results: Although FEV1, as well as the FEV1/FVC and FEV1/slow vital capacity ratios, were higher in the COPD+CHF group than in the COPD group, all major "static" volumes-RV, functional residual capacity (FRC), and TLC-were lower in the former group (p < 0.05). There was a greater reduction in FRC than in RV, resulting in the expiratory reserve volume being lower in the COPD+CHF group than in the COPD group. There were relatively proportional reductions in FRC and TLC in the two groups; therefore, IC was also comparable. Consequently, the inspiratory fraction was higher in the COPD+CHF group than in the COPD group (0.42 ± 0.10 vs. 0.36 ± 0.10; p < 0.05). Although the tidal volume/IC ratio was higher in the COPD+CHF group, the relative inspiratory reserve was remarkably similar between the two groups (0.35 ± 0.09 vs. 0.44 ± 0.14; p < 0.05). Conclusions: Despite the restrictive effects of CHF, patients with COPD+CHF have relatively higher inspiratory limits (a greater inspiratory fraction). However, those patients use only a part of those limits, probably in order to avoid critical reductions in inspiratory reserve and increases in elastic recoil. PMID:27832235

  17. Lung protection: an intervention for tidal volume reduction in a teaching intensive care unit

    Science.gov (United States)

    Briva, Arturo; Gaiero, Cristina

    2016-01-01

    Objective To determine the effect of feedback and education regarding the use of predicted body weight to adjust tidal volume in a lung-protective mechanical ventilation strategy. Methods The study was performed from October 2014 to November 2015 (12 months) in a single university polyvalent intensive care unit. We developed a combined intervention (education and feedback), placing particular attention on the importance of adjusting tidal volumes to predicted body weight bedside. In parallel, predicted body weight was estimated from knee height and included in clinical charts. Results One hundred fifty-nine patients were included. Predicted body weight assessed by knee height instead of visual evaluation revealed that the delivered tidal volume was significantly higher than predicted. After the inclusion of predicted body weight, we observed a sustained reduction in delivered tidal volume from a mean (standard error) of 8.97 ± 0.32 to 7.49 ± 0.19mL/kg (p < 0.002). Furthermore, the protocol adherence was subsequently sustained for 12 months (delivered tidal volume 7.49 ± 0.54 versus 7.62 ± 0.20mL/kg; p = 0.103). Conclusion The lack of a reliable method to estimate the predicted body weight is a significant impairment for the application of a worldwide standard of care during mechanical ventilation. A combined intervention based on education and repeated feedbacks promoted sustained tidal volume education during the study period (12 months). PMID:27925055

  18. Importance of scatter compensation algorithm in heterogeneous tissue for the radiation dose calculation of small lung nodules. A clinical study

    International Nuclear Information System (INIS)

    Baba, Yuji; Murakami, Ryuji; Mizukami, Naohisa; Morishita, Shoji; Yamashita, Yasuyuki; Araki, Fujio; Moribe, Nobuyuki; Hirata, Yukinori

    2004-01-01

    The purpose of this study was to compare radiation doses of small lung nodules calculated with beam scattering compensation and those without compensation in heterogeneous tissues. Computed tomography (CT) data of 34 small (1-2 cm: 12 nodules, 2-3 cm 11 nodules, 3-4 cm 11 nodules) lung nodules were used in the radiation dose measurements. Radiation planning for lung nodule was performed with a commercially available unit using two different radiation dose calculation methods: the superposition method (with scatter compensation in heterogeneous tissues), and the Clarkson method (without scatter compensation in heterogeneous tissues). The energy of the linac photon used in this study was 10 MV and 4 MV. Monitor unit (MU) to deliver 10 Gy at the center of the radiation field (center of the nodule) calculated with the two methods were compared. In 1-2 cm nodules, MU calculated by Clarkson method (MUc) was 90.0±1.1% (4 MV photon) and 80.5±2.7% (10 MV photon) compared to MU calculated by superposion method (MUs), in 2-3 cm nodules, MUc was 92.9±1.1% (4 MV photon) and 86.6±2.8% (10 MV photon) compared to MUs, and in 3-4 cm nodules, MUc was 90.5±2.0% (4 MV photon) and 90.1±1.7% (10 MV photon) compared to MUs. In 1-2 cm nodules, MU calculated without lung compensation (MUn) was 120.6±8.3% (4 MV photon) and 95.1±4.1% (10 MV photon) compared to MU calculated by superposion method (MUs), in 2-3 cm nodules, MUc was 120.3±11.5% (4 MV photon) and 100.5±4.6% (10 MV photon) compared to MUs, and in 3-4 cm nodules, MUc was 105.3±9.0% (4 MV photon) and 103.4±4.9% (10 MV photon) compared to MUs. The MU calculated without lung compensation was not significantly different from the MU calculated by superposition method in 2-3 cm nodules. We found that the conventional dose calculation algorithm without scatter compensation in heterogeneous tissues substantially overestimated the radiation dose of small nodules in the lung field. In the calculation of dose distribution of small

  19. Assessment of volume and leak measurements during CPAP using a neonatal lung model

    International Nuclear Information System (INIS)

    Fischer, H S; Roehr, C C; Proquitté, H; Wauer, R R; Schmalisch, G

    2008-01-01

    Although several commercial devices are available which allow tidal volume and air leak monitoring during continuous positive airway pressure (CPAP) in neonates, little is known about their measurement accuracy and about the influence of air leaks on volume measurement. The aim of this in vitro study was the validation of volume and leak measurement under CPAP using a commercial ventilatory device, taking into consideration the clinical conditions in neonatology. The measurement accuracy of the Leoni ventilator (Heinen and Löwenstein, Germany) was investigated both in a leak-free system and with leaks simulated using calibration syringes (2–10 ml, 20–100 ml) and a mechanical lung model. Open tubes of variable lengths were connected for leak simulation. Leak flow was measured with the flow-through technique. In a leak-free system the mean relative volume error ±SD was 3.5 ± 2.6% (2–10 ml) and 5.9 ± 0.7% (20–60 ml), respectively. The influence of CPAP level, driving flow, respiratory rate and humidification of the breathing gas on the volume error was negligible. However, an increasing F i O 2 caused the measured tidal volume to increase by up to 25% (F i O 2 = 1.0). The relative error ±SD of the leak measurements was −0.2 ± 11.9%. For leaks >19%, measured tidal volume was underestimated by more than 10%. In conclusion, the present in vitro study showed that the Leoni allowed accurate volume monitoring under CPAP conditions similar to neonates. Air leaks of up to 90% of patient flow were reliably detected. For an F i O 2 >0.4 and for leaks >19%, a numerical correction of the displayed volume should be performed

  20. Assessment of volume and leak measurements during CPAP using a neonatal lung model.

    Science.gov (United States)

    Fischer, H S; Roehr, C C; Proquitté, H; Wauer, R R; Schmalisch, G

    2008-01-01

    Although several commercial devices are available which allow tidal volume and air leak monitoring during continuous positive airway pressure (CPAP) in neonates, little is known about their measurement accuracy and about the influence of air leaks on volume measurement. The aim of this in vitro study was the validation of volume and leak measurement under CPAP using a commercial ventilatory device, taking into consideration the clinical conditions in neonatology. The measurement accuracy of the Leoni ventilator (Heinen & Löwenstein, Germany) was investigated both in a leak-free system and with leaks simulated using calibration syringes (2-10 ml, 20-100 ml) and a mechanical lung model. Open tubes of variable lengths were connected for leak simulation. Leak flow was measured with the flow-through technique. In a leak-free system the mean relative volume error +/-SD was 3.5 +/- 2.6% (2-10 ml) and 5.9 +/- 0.7% (20-60 ml), respectively. The influence of CPAP level, driving flow, respiratory rate and humidification of the breathing gas on the volume error was negligible. However, an increasing F(i)O(2) caused the measured tidal volume to increase by up to 25% (F(i)O(2) = 1.0). The relative error +/- SD of the leak measurements was -0.2 +/- 11.9%. For leaks > 19%, measured tidal volume was underestimated by more than 10%. In conclusion, the present in vitro study showed that the Leoni allowed accurate volume monitoring under CPAP conditions similar to neonates. Air leaks of up to 90% of patient flow were reliably detected. For an F(i)O(2) > 0.4 and for leaks > 19%, a numerical correction of the displayed volume should be performed.

  1. Waste retrieval sluicing system campaign number 1 solids volume transferred calculation

    International Nuclear Information System (INIS)

    BAILEY, J.W.

    1999-01-01

    This calculation has been prepared to document the volume of sludge removed from tank 241-C-106 during Waste Retrieval Sluicing System (WRSS) Sluicing Campaign No.1. This calculation will be updated, if necessary, to incorporate new data. This calculation supports the declaration of completion of WRSS Campaign No.1 and, as such, is also the documentation for completion of Performance Agreement TWR 1.2.1 , C-106 Sluicing Performance Expectations. It documents the performance of all the appropriate tank 241-C-106 mass transfer verifications, evaluations, and appropriate adjustments discussed in HNF-SD-WM-PROC-021, Chapter 23, ''Process Engineering Calculations for Tank 241-C-106 Sluicing and Retrieval''

  2. Waste retrieval sluicing system campaign number 1 solids volume transferred calculation

    International Nuclear Information System (INIS)

    BAILEY, J.W.

    1999-01-01

    This calculation has been prepared to document the volume of sludge removed from tank 241-C-106 during Waste Retrieval Sluicing System (WRSS) Sluicing Campaign No.1. This calculation will be updated, if necessary, to incorporate new data. This calculation supports the declaration of completion of WRSS Campaign No.1 and, as such, is also the documentation for completion of Performance Agreement TWR 1.2.1 C-106 Sluicing Performance Expectations. It documents the performance of all the appropriate tank 241-C-106 mass transfer verifications, evaluations, and appropriate adjustments discussed in HNF-SD-WM-PROC-021, Chapter 23, ''Process Engineering Calculations for Tank 241-C-106 Sluicing and Retrieval''

  3. Lung function in North American Indian children: reference standards for spirometry, maximal expiratory flow volume curves, and peak expiratory flow.

    Science.gov (United States)

    Wall, M A; Olson, D; Bonn, B A; Creelman, T; Buist, A S

    1982-02-01

    Reference standards of lung function was determined in 176 healthy North American Indian children (94 girls, 82 boys) 7 to 18 yr of age. Spirometry, maximal expiratory flow volume curves, and peak expiratory flow rate were measured using techniques and equipment recommended by the American Thoracic Society. Standing height was found to be an accurate predictor of lung function, and prediction equations for each lung function variable are presented using standing height as the independent variable. Lung volumes and expiratory flow rates in North American Indian children were similar to those previously reported for white and Mexican-American children but were greater than those in black children. In both boys and girls, lung function increased in a curvilinear fashion. Volume-adjusted maximal expiratory flow rates after expiring 50 or 75% of FVC tended to decrease in both sexes as age and height increased. Our maximal expiratory flow volume curve data suggest that as North American Indian children grow, lung volume increases at a slightly faster rate than airway size does.

  4. 3D CT modeling of hepatic vessel architecture and volume calculation in living donated liver transplantation

    International Nuclear Information System (INIS)

    Frericks, Bernd B.; Caldarone, Franco C.; Savellano, Dagmar Hoegemann; Stamm, Georg; Kirchhoff, Timm D.; Shin, Hoen-Oh; Galanski, Michael; Nashan, Bjoern; Klempnauer, Juergen; Schenk, Andrea; Selle, Dirk; Spindler, Wolf; Peitgen, Heinz-Otto

    2004-01-01

    The aim of this study was to evaluate a software tool for non-invasive preoperative volumetric assessment of potential donors in living donated liver transplantation (LDLT). Biphasic helical CT was performed in 56 potential donors. Data sets were post-processed using a non-commercial software tool for segmentation, volumetric analysis and visualisation of liver segments. Semi-automatic definition of liver margins allowed the segmentation of parenchyma. Hepatic vessels were delineated using a region-growing algorithm with automatically determined thresholds. Volumes and shapes of liver segments were calculated automatically based on individual portal-venous branches. Results were visualised three-dimensionally and statistically compared with conventional volumetry and the intraoperative findings in 27 transplanted cases. Image processing was easy to perform within 23 min. Of the 56 potential donors, 27 were excluded from LDLT because of inappropriate liver parenchyma or vascular architecture. Two recipients were not transplanted due to poor clinical conditions. In the 27 transplanted cases, preoperatively visualised vessels were confirmed, and only one undetected accessory hepatic vein was revealed. Calculated graft volumes were 1110±180 ml for right lobes, 820 ml for the left lobe and 270±30 ml for segments II+III. The calculated volumes and intraoperatively measured graft volumes correlated significantly. No significant differences between the presented automatic volumetry and the conventional volumetry were observed. A novel image processing technique was evaluated which allows a semi-automatic volume calculation and 3D visualisation of the different liver segments. (orig.)

  5. Nuclear criticality safety experiments, calculations, and analyses: 1958 to 1982. Volume 1. Lookup tables

    International Nuclear Information System (INIS)

    Koponen, B.L.; Hampel, V.E.

    1982-01-01

    This compilation contains 688 complete summaries of papers on nuclear criticality safety as presented at meetings of the American Nuclear Society (ANS). The selected papers contain criticality parameters for fissile materials derived from experiments and calculations, as well as criticality safety analyses for fissile material processing, transport, and storage. The compilation was developed as a component of the Nuclear Criticality Information System (NCIS) now under development at the Lawrence Livermore National Laboratory. The compilation is presented in two volumes: Volume 1 contains a directory to the ANS Transaction volume and page number where each summary was originally published, the author concordance, and the subject concordance derived from the keyphrases in titles. Volume 2 contains - in chronological order - the full-text summaries, reproduced here by permission of the American Nuclear Society from their Transactions, volumes 1-41

  6. Fast Near-Field Calculation for Volume Integral Equations for Layered Media

    DEFF Research Database (Denmark)

    Kim, Oleksiy S.; Meincke, Peter; Breinbjerg, Olav

    2005-01-01

    . Afterwards, the scattered electric field can be easily computed at a regular rectangular grid on any horizontal plane us-ing a 2-dimensional FFT. This approach provides significant speedup in the near-field calculation in comparison to a straightforward numerical evaluation of the ra-diation integral since......An efficient technique based on the Fast Fourier Transform (FFT) for calculating near-field scattering by dielectric objects in layered media is presented. A higher or-der method of moments technique is employed to solve the volume integral equation for the unknown induced volume current density...

  7. Development of computerized stocktaking system in mine surveying for ore mineral volume calculation in covered storehouses

    Science.gov (United States)

    Valdman, V. V.; Gridnev, S. O.

    2017-10-01

    The article examines into the vital issues of measuring and calculating the raw stock volumes in covered storehouses at mining and processing plants. The authors bring out two state-of-the-art high-technology solutions: 1 - to use the ground-based laser scanning system (the method is reasonably accurate and dependable, but costly and time consuming; it also requires the stoppage of works in the storehouse); 2 - to use the fundamentally new computerized stocktaking system in mine surveying for the ore mineral volume calculation, based on the profile digital images. These images are obtained via vertical projection of the laser plane onto the surface of the stored raw materials.

  8. Pulmonary Perfusion Changes as Assessed by Contrast-Enhanced Dual-Energy Computed Tomography after Endoscopic Lung Volume Reduction by Coils.

    Science.gov (United States)

    Lador, Frédéric; Hachulla, Anne-Lise; Hohn, Olivia; Plojoux, Jérôme; Ronot, Maxime; Montet, Xavier; Soccal, Paola M

    2016-01-01

    Endoscopic lung volume reduction by coils (LVRC) is a recent treatment approach for severe emphysema. Furthermore, dual-energy computed tomography (DECT) now offers a combined assessment of lung morphology and pulmonary perfusion. The aim of our study was to assess the impact of LVRC on pulmonary perfusion with DECT. Seventeen patients (64.8 ± 6.7 years) underwent LVRC. DECT was performed prior to and after LVRC. For each patient, lung volumes and emphysema quantification were automatically calculated. Then, 6 regions of interest (ROIs) on the iodine perfusion map were drawn in the anterior, mid, and posterior right and left lungs at 4 defined levels. The ROI values were averaged to obtain lung perfusion as assessed by the lung's iodine concentration (CLung, μg·cm-3). The CLung values were normalized using the left atrial iodine concentration (CLA) to take into account differences between successive DECT scans. The 6-min walk distance (6MWD) improved significantly after the procedure (p = 0.0002). No lung volume changes were observed between successive DECT scans for any of the patients (p = 0.32), attesting the same suspended inspiration. After LVRC, the emphysema index was significantly reduced in the treated lung (p = 0.0014). Lung perfusion increased significantly adjacent to the treated areas (CLung/CLA from 3.4 ± 1.7 to 5.6 ± 2.2, p < 0.001) and in the ipsilateral untreated areas (from 4.1 ± 1.4 to 6.6 ± 1.7, p < 0.001), corresponding to a mean 65 and 61% increase in perfusion, respectively. No significant difference was observed in the contralateral upper and lower areas (from 4.4 ± 1.9 to 4.8 ± 2.1, p = 0.273, and from 4.9 ± 2.0 to 5.2 ± 1.7, p = 0.412, respectively). A significant correlation between increased 6MWD and increased perfusion was found (p = 0.0027, R2 = 0.3850). Quantitative analysis based on DECT acquisition revealed that LVRC results in a significant increase in perfusion in the coil-free areas adjacent to the treated ones, as

  9. A Pilot Study on the Feasibility of Interventional Lung Volume Reduction

    International Nuclear Information System (INIS)

    Wang Wansheng; Dong Yonghua; Liu Bin; Zhu Chi; Yu Yongqiang

    2008-01-01

    The objective of this study was to evaluate the feasibility and safety of lung volume reduction by transbronchial alcohol and lipiodol suspension infusion with the aid of balloon-tipped catheter occlusion. Twenty-six healthy adult rabbits were divided into four treatment groups: alcohol and lipiodol suspension infusion (n = 8), lipiodol infusion (n = 8), alcohol infusion (n = 5), or bronchial lumen occlusion (n = 5). After selective lobar or segmental bronchial catheterization using a balloon-tipped occlusion catheter, the corresponding drug infusion was performed. Bone cement was used to occlude the bronchial lumen in the occlusion group. The animals were followed up for 10 weeks by chest X-ray and computed tomography (CT), and then the whole lungs were harvested for histological examination. Alcohol and lipiodol suspension or lipiodol could be stably retained in alveoli in the first two groups based on chest X-ray and CT, but obvious collapse only occurred in the group receiving alcohol and lipiodol suspension or the bronchial lumen occlusion group. Histological examination revealed damage and disruption of the alveolar epithelium and fibrosis in related lung tissue in the group receiving alcohol and lipiodol suspension. Similar changes were seen in the bronchial lumen occlusion group, apart from obvious marginal emphysema of the target areas in two animals. Interstitial pneumonia and dilated alveoli existed in some tissue in target areas in the lipiodol group, in which pulmonary fibrosis obliterating alveoli also occurred. Chronic alveolitis and pleural adhesion in target areas occurred in the group infused with alcohol alone, whereas visceral pleura of the other three groups was regular and no pleural effusion or adhesion was found. Alcohol and lipiodol suspension that is stably retained in alveoli can result in significant lung volume reduction. Through alcohol and lipiodol suspension infusion, obstructive emphysema or pneumonia arising from bronchial lumen

  10. On the Potential Role of MRI Biomarkers of COPD to Guide Bronchoscopic Lung Volume Reduction.

    Science.gov (United States)

    Adams, Colin J; Capaldi, Dante P I; Di Cesare, Robert; McCormack, David G; Parraga, Grace

    2018-02-01

    In patients with severe emphysema and poor quality of life, bronchoscopic lung volume reduction (BLVR) may be considered and guided based on lobar emphysema severity. In particular, x-ray computed tomography (CT) emphysema measurements are used to identify the most diseased and the second-most diseased lobes as BLVR targets. Inhaled gas magnetic resonance imaging (MRI) also provides chronic obstructive pulmonary disease (COPD) biomarkers of lobar emphysema and ventilation abnormalities. Our objective was to retrospectively evaluate CT and MRI biomarkers of lobar emphysema and ventilation in patients with COPD eligible for BLVR. We hypothesized that MRI would provide complementary biomarkers of emphysema and ventilation that help determine the most appropriate lung lobar targets for BLVR in patients with COPD. We retrospectively evaluated 22 BLVR-eligible patients from the Thoracic Imaging Network of Canada cohort (diffusing capacity of the lung for carbon monoxide = 37 ± 12% predicted , forced expiratory volume in 1 second = 34 ± 7% predicted , total lung capacity = 131 ± 17% predicted , and residual volume = 216 ± 36% predicted ). Lobar CT emphysema, measured using a relative area of concept retrospective analysis, quantitative MRI ventilation and CT emphysema measurements provided different BLVR targets in over 30% of the patients. The presence of large MRI ventilation defects in lobes next to CT-targeted lobes might also change the decision to proceed or to guide BLVR to a different lobar target. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

  11. Overweight Is an Independent Risk Factor for Reduced Lung Volumes in Myotonic Dystrophy Type 1.

    Directory of Open Access Journals (Sweden)

    Charlotte G W Seijger

    Full Text Available In this large observational study population of 105 myotonic dystrophy type 1 (DM1 patients, we investigate whether bodyweight is a contributor of total lung capacity (TLC independent of the impaired inspiratory muscle strength.Body composition was assessed using the combination of body mass index (BMI and fat-free mass index. Pulmonary function tests and respiratory muscle strength measurements were performed on the same day. Patients were stratified into normal (BMI < 25 kg/m(2 and overweight (BMI ≥ 25 kg/m(2 groups. Multiple linear regression was used to find significant contributors for TLC.Overweight was present in 59% of patients, and body composition was abnormal in almost all patients. In overweight patients, TLC was significantly (p = 2.40×10(-3 decreased, compared with normal-weight patients, while inspiratory muscle strength was similar in both groups. The decrease in TLC in overweight patients was mainly due to a decrease in expiratory reserve volume (ERV further illustrated by a highly significant (p = 1.33×10(-10 correlation between BMI and ERV. Multiple linear regression showed that TLC can be predicted using only BMI and the forced inspiratory volume in 1 second, as these were the only significant contributors.This study shows that, in DM1 patients, overweight further reduces lung volumes, as does impaired inspiratory muscle strength. Additionally, body composition is abnormal in almost all DM1 patients.

  12. Differences in absorbed doses at risk organs and target tumoral of planning(PTV) in lung treatments using two algorithms of different calculations

    International Nuclear Information System (INIS)

    Uruena Llinares, A.; Santos Rubio, A.; Luis Simon, F. J.; Sanchez Carmona, G.; Herrador Cordoba, M.

    2006-01-01

    The objective of this paper is to compare, in thirty treatments for lung cancer,the absorbed doses at risk organs and target volumes obtained between the two used algorithms of calculation of our treatment planning system Oncentra Masterplan, that is, Pencil Beams vs Collapsed Cone. For it we use a set of measured indicators (D1 and D99 of tumor volume, V20 of lung, homogeneity index defined as (D5-D95)/D prescribed, and others). Analysing the dta, making a descriptor analysis of the results, and applying the non parametric test of the ranks with sign of Wilcoxon we find that the use of Pencil Beam algorithm underestimates the dose in the zone of the PTV including regions of low density as well as the values of maximum dose in spine cord. So, we conclude that in those treatments in which the spine dose is near the maximum permissible limit or those in which the PTV it includes a zone with pulmonary tissue must be used the Collapse Cone algorithm systematically and in any case an analysis must become to choose between time and precision in the calculation for both algorithms. (Authors)

  13. Visual classification of emphysema heterogeneity compared with objective measurements: HRCT vs spiral CT in candidates for lung volume reduction surgery

    International Nuclear Information System (INIS)

    Cederlund, K.; Hoegberg, S.; Rasmussen, E.; Svane, B.; Bergstrand, L.; Tylen, U.; Aspelin, P.

    2002-01-01

    The aim of this study was to investigate whether spiral CT is superior to high-resolution computed tomography (HRCT) in evaluating the radiological morphology of emphysema, and whether the combination of both CT techniques improves the evaluation in patients undergoing lung volume reduction surgery (LVRS). The material consisted of HRCT (with 2-mm slice thickness) and spiral CT (with 10-mm slice thickness) of 94 candidates for LVRS. Selected image pairs from these examinations were evaluated. Each image pair consisted of one image from the cranial part of the lung and one image from the caudal part. The degree of emphysema in the two images was calculated by computer. The difference between the images determined the degree of heterogeneity. Five classes of heterogeneity were defined. The study was performed by visual classification of 95 image pairs (spiral CT) and 95 image pairs (HRCT) into one of five different classes of emphysema heterogeneity. This visual classification was compared with the computer-based classification. Spiral CT was superior to HRCT with 47% correct classifications of emphysema heterogeneity compared with 40% for HRCT-based classification (p<0.05). The combination of the techniques did not improve the evaluation (42%). Spiral CT is superior to HRCT in determining heterogeneity of emphysema visually, and should be included in the pre-operative CT evaluation of LVRS candidates. (orig.)

  14. Visual classification of emphysema heterogeneity compared with objective measurements: HRCT vs spiral CT in candidates for lung volume reduction surgery

    Energy Technology Data Exchange (ETDEWEB)

    Cederlund, K.; Hoegberg, S.; Rasmussen, E.; Svane, B. [Department of Thoracic Radiology, Karolinska Hospital, Stockholm (Sweden); Bergstrand, L. [Department of Radiology, Danderyds Hospital, Danderyd (Sweden); Tylen, U. [Deparment of Radiology, Sahlgrenska University Hospital, Gothenberg (Sweden); Aspelin, P. [Department of Radiology, Huddinge University Hospital, Huddinge (Sweden)

    2002-05-01

    The aim of this study was to investigate whether spiral CT is superior to high-resolution computed tomography (HRCT) in evaluating the radiological morphology of emphysema, and whether the combination of both CT techniques improves the evaluation in patients undergoing lung volume reduction surgery (LVRS). The material consisted of HRCT (with 2-mm slice thickness) and spiral CT (with 10-mm slice thickness) of 94 candidates for LVRS. Selected image pairs from these examinations were evaluated. Each image pair consisted of one image from the cranial part of the lung and one image from the caudal part. The degree of emphysema in the two images was calculated by computer. The difference between the images determined the degree of heterogeneity. Five classes of heterogeneity were defined. The study was performed by visual classification of 95 image pairs (spiral CT) and 95 image pairs (HRCT) into one of five different classes of emphysema heterogeneity. This visual classification was compared with the computer-based classification. Spiral CT was superior to HRCT with 47% correct classifications of emphysema heterogeneity compared with 40% for HRCT-based classification (p<0.05). The combination of the techniques did not improve the evaluation (42%). Spiral CT is superior to HRCT in determining heterogeneity of emphysema visually, and should be included in the pre-operative CT evaluation of LVRS candidates. (orig.)

  15. Action of the isolated canine diaphragm on the lower ribs at high lung volumes.

    Science.gov (United States)

    De Troyer, André; Wilson, Theodore A

    2014-10-15

    The normal diaphragm has an inspiratory action on the lower ribs, but subjects with chronic obstructive pulmonary disease commonly have an inward displacement of the lateral portions of the lower rib cage during inspiration. This paradoxical displacement, conventionally called 'Hoover's sign', has traditionally been attributed to the direct action of radially oriented diaphragmatic muscle fibres. In the present study, the inspiratory intercostal muscles in all interspaces in anaesthetized dogs were severed so that the diaphragm was the only muscle active during inspiration. The displacements of the lower ribs along the craniocaudal and laterolateral axes and the changes in pleural pressure (∆Ppl) and transdiaphragmatic pressure were measured during occluded breaths and mechanical ventilation at different lung volumes between functional residual capacity (FRC) and total lung capacity. From these data, the separate effects on rib displacement of ∆Ppl and of the force exerted by the diaphragm on the ribs were determined. Isolated spontaneous diaphragm contraction at FRC displaced the lower ribs cranially and outward, but this motion was progressively reversed into a caudal and inward motion as lung volume increased. However, although the force exerted by the diaphragm on the ribs decreased with increasing volume, it continued to displace the ribs cranially and outward. These observations suggest that Hoover's sign is usually caused by the decrease in the zone of apposition and, thus, by the dominant effect of ∆Ppl on the lower ribs, rather than an inward pull from the diaphragm. © 2014 The Authors. The Journal of Physiology © 2014 The Physiological Society.

  16. Minimally invasive lung volume reduction treated with bronchi occlusion emphysema model

    International Nuclear Information System (INIS)

    Zhou Dayong; Shen Liming; Shen Junkang; Jin Yiqi; Chen Lei; Huang Xianchen

    2007-01-01

    Objective: To evaluate the efficacy and feasibility of the coil-and-glue method for the reduction of lung volume in rabbit emphysema model. Methods: Sixteen rabbits of emphysema model were divided into the occlusion group(n=10), in which both anterior bronchi were occluded using the coil-and- glue method, and the control group (n=6). The maximal static pressure of airway (P max ), peak expiratory flow (PEF), end-expiratory volume (EEV) and pressure of oxygen (PO 2 ) were measured at ante- emphysema, post-emphysema, 1 week and 4 week after occlusion respectively. The expectoration (or migration) of coil and collapse of lung were also investigated. Results: P max was (20.0±1.3) and (17.1± 1.4) cm H 2 O (1 cm H 2 O=0.098 kPa) in the occlusion group at ante-emphysema and post-emphysema respectively. P max was (19.2±1.4) cm H 2 O in the occlusion group in the 1 week after the occlusion, while (17.1±1.5)cm H 2 O in the control group (F=6.68, P max was (19.2±1.4) cm H 2 O in the occlusion group, while (16.6±1.2) cm H 2 O in the control group (F=12.10, P max , in the 1 week and 4 week after occlusion were higher than those at post-emphysema (P<0.01, respectively); EEV at post-emphysema was higher than that at ante-emphysema (P<0.01). Conclusion: Coil-and-glue occlusion method for lung volume reduction in rabbit emphysema model can improve the pulmonary function, which can be relatively long lasting. (authors)

  17. Comparison of image features calculated in different dimensions for computer-aided diagnosis of lung nodules

    Science.gov (United States)

    Xu, Ye; Lee, Michael C.; Boroczky, Lilla; Cann, Aaron D.; Borczuk, Alain C.; Kawut, Steven M.; Powell, Charles A.

    2009-02-01

    Features calculated from different dimensions of images capture quantitative information of the lung nodules through one or multiple image slices. Previously published computer-aided diagnosis (CADx) systems have used either twodimensional (2D) or three-dimensional (3D) features, though there has been little systematic analysis of the relevance of the different dimensions and of the impact of combining different dimensions. The aim of this study is to determine the importance of combining features calculated in different dimensions. We have performed CADx experiments on 125 pulmonary nodules imaged using multi-detector row CT (MDCT). The CADx system computed 192 2D, 2.5D, and 3D image features of the lesions. Leave-one-out experiments were performed using five different combinations of features from different dimensions: 2D, 3D, 2.5D, 2D+3D, and 2D+3D+2.5D. The experiments were performed ten times for each group. Accuracy, sensitivity and specificity were used to evaluate the performance. Wilcoxon signed-rank tests were applied to compare the classification results from these five different combinations of features. Our results showed that 3D image features generate the best result compared with other combinations of features. This suggests one approach to potentially reducing the dimensionality of the CADx data space and the computational complexity of the system while maintaining diagnostic accuracy.

  18. High spatiotemporal resolution measurement of regional lung air volumes from 2D phase contrast x-ray images.

    Science.gov (United States)

    Leong, Andrew F T; Fouras, Andreas; Islam, M Sirajul; Wallace, Megan J; Hooper, Stuart B; Kitchen, Marcus J

    2013-04-01

    Described herein is a new technique for measuring regional lung air volumes from two-dimensional propagation-based phase contrast x-ray (PBI) images at very high spatial and temporal resolution. Phase contrast dramatically increases lung visibility and the outlined volumetric reconstruction technique quantifies dynamic changes in respiratory function. These methods can be used for assessing pulmonary disease and injury and for optimizing mechanical ventilation techniques for preterm infants using animal models. The volumetric reconstruction combines the algorithms of temporal subtraction and single image phase retrieval (SIPR) to isolate the image of the lungs from the thoracic cage in order to measure regional lung air volumes. The SIPR algorithm was used to recover the change in projected thickness of the lungs on a pixel-by-pixel basis (pixel dimensions ≈ 16.2 μm). The technique has been validated using numerical simulation and compared results of measuring regional lung air volumes with and without the use of temporal subtraction for removing the thoracic cage. To test this approach, a series of PBI images of newborn rabbit pups mechanically ventilated at different frequencies was employed. Regional lung air volumes measured from PBI images of newborn rabbit pups showed on average an improvement of at least 20% in 16% of pixels within the lungs in comparison to that measured without the use of temporal subtraction. The majority of pixels that showed an improvement was found to be in regions occupied by bone. Applying the volumetric technique to sequences of PBI images of newborn rabbit pups, it is shown that lung aeration at birth can be highly heterogeneous. This paper presents an image segmentation technique based on temporal subtraction that has successfully been used to isolate the lungs from PBI chest images, allowing the change in lung air volume to be measured over regions as small as the pixel size. Using this technique, it is possible to measure

  19. Analysis of decrease in lung perfusion blood volume with occlusive and non-occlusive pulmonary embolisms

    International Nuclear Information System (INIS)

    Ikeda, Yohei; Yoshimura, Norihiko; Hori, Yoshiro; Horii, Yosuke; Ishikawa, Hiroyuki; Yamazaki, Motohiko; Noto, Yoshiyuki; Aoyama, Hidefumi

    2014-01-01

    Highlights: • The proportion of preserved PE lesions in the non-occlusive group was 76.7% (33/43). • HUs of the iodine map were significantly higher in the non-occlusive group than in the occlusive group. • There was no significant difference in HUs between the non-occlusive and corresponding normal group. - Abstract: Purpose: The aim of this study was to determine if lung perfusion blood volume (lung PBV) with non-occlusive pulmonary embolism (PE) differs quantitatively and visually from that with occlusive PE and to investigate if lung PBV with non-occlusive PE remains the same as that without PE. Materials and methods: Totally, 108 patients suspected of having acute PE underwent pulmonary dual-energy computed tomography angiography (DECTA) between April 2011 and January 2012. Presence of PE on DECTA was evaluated by one radiologist. Two radiologists visually evaluated the PE distribution (segmental or subsegmental) and its nature (occlusive or non-occlusive) on DECTA and classified perfusion in lung PBV as “decreased,” “slightly decreased,” and “preserved”. Two radiologists used a lung PBV application to set a region of interest (ROI) in the center of the lesion and measured HU values of an iodine map. In the same slice as the ROI of the lesion and close to the lesion, another ROI was set in the normal perfusion area without PE, and HUs were measured. The proportion of lesions was compared between the occlusive and non-occlusive groups. HUs were compared among the occlusive, non-occlusive, and corresponding normal groups. Results: Twenty-five patients had 80 segmental or subsegmental lesions. There were 37 and 43 lesions in the occlusive and non-occlusive groups, respectively. The proportion of decreased lesions was 73.0% (27/37) in the occlusive group, while that of preserved lesions in the non-occlusive group was 76.7% (33/43). There was a significant difference in the proportion of lesions (P < 0.001) between the two groups. HUs of the

  20. New reference charts for testicular volume in Dutch children and adolescents allow the calculation of standard deviation scores

    NARCIS (Netherlands)

    Joustra, S.D.; Plas, E.M. van der; Goede, J.; Oostdijk, W.; Delemarre-van de Waal, H.A.; Hack, W.W.M.; Buuren, S. van; Wit, J.M.

    2015-01-01

    Aim Accurate calculations of testicular volume standard deviation (SD) scores are not currently available. We constructed LMS-smoothed age-reference charts for testicular volume in healthy boys. Methods The LMS method was used to calculate reference data, based on testicular volumes from

  1. Dose-volume histogram analysis as predictor of radiation pneumonitis in primary lung cancer patients treated with radiotherapy

    International Nuclear Information System (INIS)

    Fay, Michael; Tan, Alex; Fisher, Richard; Mac Manus, Michael; Wirth, Andrew; Ball, David

    2005-01-01

    Purpose: To determine the relationship between various parameters derived from lung dose-volume histogram analysis and the risk of symptomatic radiation pneumonitis (RP) in patients undergoing radical radiotherapy for primary lung cancer. Methods and Materials: The records of 156 patients with lung cancer who had been treated with radical radiotherapy (≥45 Gy) and for whom dose-volume histogram data were available were reviewed. The incidence of symptomatic RP was correlated with a variety of parameters derived from the dose-volume histogram data, including the volume of lung receiving 10 Gy (V 10 ) through 50 Gy (V 50 ) and the mean lung dose (MLD). Results: The rate of RP at 6 months was 15% (95% confidence interval 9-22%). On univariate analysis, only V 30 (p = 0.036) and MLD (p = 0.043) were statistically significantly related to RP. V 30 correlated highly positively with MLD (r = 0.96, p 30 and MLD can be used to predict the risk of RP in lung cancer patients undergoing radical radiotherapy

  2. A correlation study on position and volume variation of primary lung cancer during respiration by four-dimensional CT

    International Nuclear Information System (INIS)

    Zhang Yingjie; Li Jianbin; Tian Shiyu; Li Fengxiang; Fan Tingyong; Shao Qian; Xu Min; Lu Jie

    2011-01-01

    Objective: To investigate the correlation of position movement of primary tumor with interested organs and skin markers, and to investigate the correlation of volume variation of primary tumors and lungs during different respiration phases for patients with lung cancer at free breath condition scanned by four-dimensional CT (4DCT) simulation. Methods: 16 patients with lung cancer were scanned at free breath condition by simulation 4DCT which connected to a respiration-monitoring system. A coordinate system was created based on image of T 5 phase,gross tumor volume (GTV) and normal tissue structures of 10 phases were contoured. The three dimensional position variation of them were measured and their correlation were analyzed, and the same for the volume variation of GTV and lungs of 10 respiratory phases. Results: Movement range of lung cancer in different lobe differed extinct: 0.8 - 5.0 mm in upper lobe, 5.7 -5.9 mm in middle lobe and 10.2 - 13.7 mm in lower lobe, respectively. Movement range of lung cancer in three dimensional direction was different: z-axis 4.3 mm ± 4.3 mm > y-axis 2.2 mm ± 1.0 mm > x-axis 1.7 mm ± 1.5 mm (χ 2 =16.22, P =0.000), respectively. There was no statistical significant correlation for movement vector of GTV and interested structures (r =-0.50 - -0.01, P =0.058 - -0.961), nor for volume variation of tumor and lung (r =0.23, P =0.520). Conclusions: Based on 4DCT, statistically significant differences of GTV centroid movement are observed at different pulmonary lobes and in three dimensional directions. So individual 4DCT measurement is necessary for definition of internal target volume margin for lung cancer. (authors)

  3. 40 CFR 80.1407 - How are the Renewable Volume Obligations calculated?

    Science.gov (United States)

    2010-07-01

    ... is calculated as follows: ER26MR10.430 Where: x = Individual batch of gasoline produced or imported in calendar year i. n = Total number of batches of gasoline produced or imported in calendar year i. GX = Volume of batch x of gasoline produced or imported, as defined in paragraph (c) of this section...

  4. 40 CFR 80.1107 - How is the Renewable Volume Obligation calculated?

    Science.gov (United States)

    2010-07-01

    ... this section is calculated as follows: ER01MY07.061 Where: x = Individual batch of gasoline produced or imported in calendar year i. n = Total number of batches of gasoline produced or imported in calendar year i. GX = Volume of batch x of gasoline produced or imported, in gallons. y = Individual batch of...

  5. ALBEMO, a program for the calculation of the radiation transport in void volumes with reflecting walls

    International Nuclear Information System (INIS)

    Mueller, K.; Vossebrecker, H.

    The Monte Carlo Program ALBEMO calculates the distribution of neutrons and gamma rays in void volumes which are bounded by reflecting walls with x, y, z coordinates. The program is based on the albedo method. The effect of significant simplifying assumptions is investigated. Comparisons with experiments show satisfying agreement

  6. Quantification and Minimization of Uncertainties of Internal Target Volume for Stereotactic Body Radiation Therapy of Lung Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Ge Hong [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Department of Radiation Oncology, Henan Cancer Hospital, the Affiliated Cancer Hospital of Zhengzhou University, Henan (China); Cai Jing; Kelsey, Chris R. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States); Yin Fangfang, E-mail: fangfang.yin@duke.edu [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina (United States)

    2013-02-01

    Purpose: To quantify uncertainties in delineating an internal target volume (ITV) and to understand how these uncertainties may be individually minimized for stereotactic body radiation therapy (SBRT) of early stage non-small cell lung cancer (NSCLC). Methods and Materials: Twenty patients with NSCLC who were undergoing SBRT were imaged with free-breathing 3-dimensional computed tomography (3DCT) and 10-phase 4-dimensional CT (4DCT) for delineating gross tumor volume (GTV){sub 3D} and ITV{sub 10Phase} (ITV3). The maximum intensity projection (MIP) CT was also calculated from 10-phase 4DCT for contouring ITV{sub MIP} (ITV1). Then, ITV{sub COMB} (ITV2), ITV{sub 10Phase+GTV3D} (ITV4), and ITV{sub 10Phase+ITVCOMB} (ITV5) were generated by combining ITV{sub MIP} and GTV{sub 3D}, ITV{sub 10phase} and GTV{sub 3D}, and ITV{sub 10phase} and ITV{sub COMB}, respectively. All 6 volumes (GTV{sub 3D} and ITV1 to ITV5) were delineated in the same lung window by the same radiation oncologist. The percentage of volume difference (PVD) between any 2 different volumes was determined and was correlated to effective tumor diameter (ETD), tumor motion ranges, R{sub 3D}, and the amplitude variability of the recorded breathing signal (v) to assess their volume variations. Results: The mean (range) tumor motion (R{sub SI}, R{sub AP}, R{sub ML}, and R{sub 3D}) and breathing variability (v) were 7.6 mm (2-18 mm), 4.0 mm (2-8 mm), 3.3 mm (0-7.5 mm), 9.9 mm (4.1-18.7 mm), and 0.17 (0.07-0.37), respectively. The trend of volume variation was GTV{sub 3D} volumes were 11.1 {+-} 9.3 cc, 13.2 {+-} 10.5 cc, 14.9 {+-} 11.0 cc, 14.7 {+-} 11.4 cc, 15.9 {+-} 11.7 cc, and 16.4 {+-} 11.8 cc, respectively. All comparisons between the target volumes showed statistical significance (P{<=}.001), except for ITV2 and ITV3 (P=.594). The PVDs for all volume pairs correlated negatively with ETD (r{<=}-0.658, P{<=}.006) and positively with

  7. Relationship of end-expiratory pressure, lung volume, and /sup 99m/Tc-DTPA clearance

    International Nuclear Information System (INIS)

    Cooper, J.A.; van der Zee, H.; Line, B.R.; Malik, A.B.

    1987-01-01

    We investigated the dose-response effect of positive end-expiratory pressure (PEEP) and increased lung volume on the pulmonary clearance rate of aerosolized technetium-99m-labeled diethylenetriaminepentaacetic acid (99mTc-DTPA). Clearance of lung radioactivity was expressed as percent decrease per minute. Base-line clearance was measured while anesthetized sheep (n = 20) were ventilated with 0 cmH 2 O end-expiratory pressure. Clearance was remeasured during ventilation at 2.5, 5, 10, 15, or 20 cmH 2 O PEEP. Further studies showed stepwise increases in functional residual capacity (FRC) (P less than 0.05) measured at 0, 2.5, 5, 10, 15, and 20 cmH 2 O PEEP. At 2.5 cmH 2 O PEEP, the clearance rate was not different from that at base line (P less than 0.05), although FRC was increased from base line. Clearance rate increased progressively with increasing PEEP at 5, 10, and 15 cmH 2 O (P less than 0.05). Between 15 and 20 cmH 2 O PEEP, clearance rate was again unchanged, despite an increase in FRC. The pulmonary clearance of aerosolized /sup 99m/Tc-DTPA shows a sigmoidal response to increasing FRC and PEEP, having both threshold and maximal effects. This relationship is most consistent with the hypothesis that alveolar epithelial permeability is increased by lung inflation

  8. Emphysema. Imaging for endoscopic lung volume reduction; Lungenemphysem. Bildgebung bei endoskopischer Lungenvolumenreduktion

    Energy Technology Data Exchange (ETDEWEB)

    Storbeck, B. [LungenClinic Grosshansdorf (Germany). Dept. of Radiology; Schroeder, T.H. [Amalie Sieveking-Hospital, Diagnostic and Interventional Radiology, Hamburg (Germany); Oldigs, M.; Rabe, K.F. [LungenClinic Grosshansdorf (Germany). Dept. of Pulmonology; Weber, C. [Amalie Sieveking-Hospital, Diagnostic and Interventional Radiology, Hamburg (Germany); University Medical Center Hamburg-Eppendorf (Germany). Diagnostic and Interventional Radiology

    2015-07-15

    Chronic obstructive pulmonary disease (COPD) is characterized by two entities, the more airway-predominant type (''bronchitis'') on the one hand, and emphysema-predominant type on the other. Imaging via high-resolution computed tomography plays an important role in phenotyping COPD. For patients with advanced lung emphysema, new endoscopic lung volume reduction therapies (ELVR) have been developed. Proper selection of suitable patients requires thin-section reconstruction of volumetric CT image data sets also in coronal and sagittal orientation are required. In the current manuscript we will describe emphysema subtypes (centrilobular, paraseptal, panlobular), options for quantifying emphysema and this importance of regional distribution (homogeneous or heterogeneous, target area) as this is crucial for patient selection. Analysis of the interlobular fissures is obligatory despite the lack of standardization, as incomplete fissures indicate collateral ventilation (CV) via parenchymal bridges, which is an important criterion in choosing endoscopic methods of LVR. Every radiologist should be familiar with modern LVR therapies such as valves and coils, and furthermore should know what a lung doctor expects from radiologic evaluation (before and after ELVR). Finally we present a checklist as a quick reference for all steps concerning imaging for ELVR.

  9. Automated lung tumor segmentation for whole body PET volume based on novel downhill region growing

    Science.gov (United States)

    Ballangan, Cherry; Wang, Xiuying; Eberl, Stefan; Fulham, Michael; Feng, Dagan

    2010-03-01

    We propose an automated lung tumor segmentation method for whole body PET images based on a novel downhill region growing (DRG) technique, which regards homogeneous tumor hotspots as 3D monotonically decreasing functions. The method has three major steps: thoracic slice extraction with K-means clustering of the slice features; hotspot segmentation with DRG; and decision tree analysis based hotspot classification. To overcome the common problem of leakage into adjacent hotspots in automated lung tumor segmentation, DRG employs the tumors' SUV monotonicity features. DRG also uses gradient magnitude of tumors' SUV to improve tumor boundary definition. We used 14 PET volumes from patients with primary NSCLC for validation. The thoracic region extraction step achieved good and consistent results for all patients despite marked differences in size and shape of the lungs and the presence of large tumors. The DRG technique was able to avoid the problem of leakage into adjacent hotspots and produced a volumetric overlap fraction of 0.61 +/- 0.13 which outperformed four other methods where the overlap fraction varied from 0.40 +/- 0.24 to 0.59 +/- 0.14. Of the 18 tumors in 14 NSCLC studies, 15 lesions were classified correctly, 2 were false negative and 15 were false positive.

  10. Soil map, area and volume calculations in Orrmyrberget catchment basin at Gideaa, Northern Sweden

    International Nuclear Information System (INIS)

    Ittner, T.; Tammela, P.T.; Gustafsson, E.

    1991-06-01

    Fallout studies in the Gideaa study site after the Chernobyl fallout in 1986, has come to the point that a more exact surface mapping of the studied catchment basin is needed. This surface mapping is mainly made for area calculations of different soil types within the study site. The mapping focus on the surface, as the study concerns fallout redistribution and it is extended to also include materials down to a depth of 0.5 meter. Volume calculations are made for the various soil materials within the top 0.5 m. These volume and area calculations will then be used in the modelling of the migration and redistribution of the fallout radionuclides within the studied catchment basin. (au)

  11. Volume-monitored chest CT: a simplified method for obtaining motion-free images near full inspiratory and end expiratory lung volumes

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Kathryn S. [The Ohio State University College of Medicine, Columbus, OH (United States); Long, Frederick R. [Nationwide Children' s Hospital, The Children' s Radiological Institute, Columbus, OH (United States); Flucke, Robert L. [Nationwide Children' s Hospital, Department of Pulmonary Medicine, Columbus, OH (United States); Castile, Robert G. [The Research Institute at Nationwide Children' s Hospital, Center for Perinatal Research, Columbus, OH (United States)

    2010-10-15

    Lung inflation and respiratory motion during chest CT affect diagnostic accuracy and reproducibility. To describe a simple volume-monitored (VM) method for performing reproducible, motion-free full inspiratory and end expiratory chest CT examinations in children. Fifty-two children with cystic fibrosis (mean age 8.8 {+-} 2.2 years) underwent pulmonary function tests and inspiratory and expiratory VM-CT scans (1.25-mm slices, 80-120 kVp, 16-40 mAs) according to an IRB-approved protocol. The VM-CT technique utilizes instruction from a respiratory therapist, a portable spirometer and real-time documentation of lung volume on a computer. CT image quality was evaluated for achievement of targeted lung-volume levels and for respiratory motion. Children achieved 95% of vital capacity during full inspiratory imaging. For end expiratory scans, 92% were at or below the child's end expiratory level. Two expiratory exams were judged to be at suboptimal volumes. Two inspiratory (4%) and three expiratory (6%) exams showed respiratory motion. Overall, 94% of scans were performed at optimal volumes without respiratory motion. The VM-CT technique is a simple, feasible method in children as young as 4 years to achieve reproducible high-quality full inspiratory and end expiratory lung CT images. (orig.)

  12. Clinical and radiological outcome following pneumothorax after endoscopic lung volume reduction with valves

    Directory of Open Access Journals (Sweden)

    Gompelmann D

    2016-12-01

    Full Text Available D Gompelmann,1,2 N Benjamin,1 K Kontogianni,1 FJF Herth,1,2 CP Heussel,2–4 H Hoffmann,2,5 R Eberhardt1,2 1Pneumology and Critical Care Medicine, Thoraxklinik at University of Heidelberg, 2German Center for Lung Research, 3Diagnostic and Interventional Radiology, Thoraxklinik at University of Heidelberg, 4Diagnostic and Interventional Radiology, University Hospital Heidelberg, 5Thoracic Surgery, Thoraxklinik at University of Heidelberg, Heidelberg, Germany Introduction: Valve implantation has evolved as a therapy for patients with advanced emphysema. Although it is a minimally invasive treatment, it is associated with complications, the most common being pneumothorax. Pneumothorax occurs due to the rapid target lobe volume reduction and may be a predictor of clinical benefit despite this complication. Objective: The objective of this study was to conduct an exploratory data analysis of patients who developed a pneumothorax following endoscopic valve therapy for emphysema. Materials and methods: This study performed a retrospective evaluation of pneumothorax management and the impact of pneumothorax on clinical outcomes in 70 patients following valve therapy in 381 consecutive patients. Results: Pneumothorax rate following valve therapy was 18%. Pneumothorax management consisted of chest tube insertion, valve removal, and surgical intervention in 87% (61/70, 44% (31/70, and 19% (13/70 of the patients, respectively. Despite pneumothorax, patients experienced modest but significant improvements in lung function parameters (forced expiratory volume in 1 second: 55±148 mL, residual volume: -390±964 mL, total lung capacity: -348±876; all P<0.05. Persistent lobar atelectasis 3 months after recovering from pneumothorax, which was associated with relevant clinical improvement, was observed in only 21% (15/70 of the patients. Conclusion: Pneumothorax is a frequent severe complication following valve therapy that requires further intervention

  13. Relationship of airway dimensions with airflow limitation or lung volumes in chronic obstructive pulmonary disease (COPD

    Directory of Open Access Journals (Sweden)

    Masaru Hasegawa

    2006-12-01

    Full Text Available We have recently developed new software to obtain longitudinal images and accurate short axis images of airways with an inner diameter > 2 mm located anywhere in the lung, using curved multiplanar reconstruction. Using this software, we demonstrated in patients with COPD that FEV1 (%predicted was highly correlated with airway dimensions and the correlation coefficients improved as the airway became smaller in size (3. In this study, our aims are to further confirm the significant relationship between airway dimensions and airflow limitation in larger number of subjects, and to examine the relationship of airway dimensions with lung volumes in 95 patients with COPD (stage 0, 10; stage I, 23; stage II, 35; stage III, 24; stage IV, 3. We analyzed the airway dimensions from the 3rd to the 6th generations of the apical bronchus (B1 of the right upper lobe and the anterior basal bronchus (B8 of the right lower lobe. Lung volumes were measured by the helium closed circuit method. Both airway luminal area (Ai and wall area percent (WA% of all the generations, except a few, from the two bronchi were significantly correlated with RV and RV/TLC, but not with TLC or FRC. More importantly, the correlation coefficients (r between airway dimensions and RV/TLC improved as the airways became smaller in size from the 3rd to 6th generations in both bronchi (r = –0.483, –0482, –0.553, –0.624 for Ai of B8; r = 0.316, 0.380, 0.499, 0.551 for WA% of B8. These findings provide further evidence that distal (small airways rather than proximal (large airways are the determinants for airflow limitation in COPD.

  14. Evaluation of pulmonary disease using static lung volumes in primary ciliary dyskinesia.

    Science.gov (United States)

    Pifferi, Massimo; Bush, Andrew; Pioggia, Giovanni; Caramella, Davide; Tartarisco, Gennaro; Di Cicco, Maria; Zangani, Marta; Chinellato, Iolanda; Maggi, Fabrizio; Tezza, Giovanna; Macchia, Pierantonio; Boner, Attilio

    2012-11-01

    In primary ciliary dyskinesia (PCD) lung damage is usually evaluated by high-resolution CT (HRCT). To evaluate whether HRCT abnormalities and Pseudomonas aeruginosa infection were better predicted by spirometry or plethysmography. A cross-sectional study performed in consecutive patients with PCD who underwent sputum culture, spirometry, plethysmography and HRCT within 48 h. Principal component analysis and soft computing were used for data evaluation. Fifty patients (26 children) were studied. P aeruginosa infection was found in 40% of the patients and bronchiectasis in 88%. There was a correlation between infection with P aeruginosa and extent of bronchiectasis (p=0.009; r =0.367) and air-trapping (p=0.03; r =0.315). Moreover, there was an association between infection with P aeruginosa and residual volume (RV) values >150% (p=0.04) and RV/total lung capacity (TLC) ratio >140% (p=0.001), but not between infection with P aeruginosa and forced expiratory volume in 1 s (FEV(1))<80%, or forced expiratory flow between 25% and 75% of forced vital capacity (FVC) (FEF(25-75%))<70% or FEV(1)/FVC<70% (<80% in children). Severity of the total lung impairment on chest HRCT directly correlated with RV when expressed as per cent predicted (p=0.003; r =0.423), and RV/TLC (p<0.001; r =0.513) or when expressed as z scores (p=0.002, r =0.451 and p<0.001, r =0.536 respectively). Principal component analysis on plethysmographic but not on spirometry data allowed recognition of different severities of focal air trapping, atelectasis and extent of bronchiectasis. Plethysmography better predicts HRCT abnormalities than spirometry. Whether it might be a useful test to define populations of patients with PCD who should or should not have HRCT scans requires further longitudinal studies.

  15. Definition of gross tumor volume in lung cancer: inter-observer variability

    International Nuclear Information System (INIS)

    Van de Steene, Jan; Linthout, Nadine; Mey, Johan de; Vinh-Hung, Vincent; Claassens, Cornelia; Noppen, Marc; Bel, Arjan; Storme, Guy

    2002-01-01

    Background and purpose: To determine the inter-observer variation in gross tumor volume (GTV) definition in lung cancer, and its clinical relevance. Material and methods: Five clinicians involved in lung cancer were asked to define GTV on the planning CT scan of eight patients. Resulting GTVs were compared on the base of geometric volume, dimensions and extensions. Judgement of invasion of lymph node (LN) regions was evaluated using the ATS/LCSG classification of LN. Clinical relevance of the variation was studied through 3D-dosimetry of standard conformal plans: volume of critical organs (heart, lungs, esophagus, spinal cord) irradiated at toxic doses, 95% isodose volumes of GTVs, normal tissue complication probabilities (NTCP) and tumor control probabilities (TCP) were compared for evaluation of observer variability. Results: Before evaluation of observer variability, critical review of planning CT scan led to up- (two cases) and downstaging (one case) of patients as compared to the respective diagnostic scans. The defined GTVs showed an inter-observer variation with a ratio up to more than 7 between maximum and minimum geometric content. The dimensions of the primary tumor had inter-observer ranges of 4.2 (transversal), 7.9 (cranio-caudal) and 5.4 (antero-posterior) cm. Extreme extensions of the GTVs (left, right, cranial, caudal, anterior and posterior) varied with ranges of 2.8-7.3 cm due to inter-observer variation. After common review, only 63% of involved lymph node regions were delineated by the clinicians (i.e. 37% are false negative). Twenty-two percent of drawn in lymph node regions were accepted to be false positive after review. In the conformal plans, inter-observer ranges of irradiated normal tissue volume were on average 12%, with a maximum of 66%. The probability (in the population of all conformal plans) of irradiating at least 95% of the GTV with at least 95% of the nominal treatment dose decreased from 96 to 88% when swapping the matched GTV

  16. BED-Volume histograms calculation for routine clinical dosimetry in brachytherapy

    International Nuclear Information System (INIS)

    Galelli, M.; Feroldi, P.

    1995-01-01

    The consideration of volumes is essential in Brachytherapy clinical dosimetry (I.C.R.U). Indeed, several indices, all based on dose-volume histograms (DVHs), have been designed in order to evaluate: before the therapy the volumetric quality of different possible implant geometries; during the therapy the consistency of the real and the previsional implants. Radiobiological evaluations, considering the dose deposition temporal pattern of treatment, can be usefully added to dosimetric calculations, to compare different treatment schedules. The Linear-Quadratic model is the most used: radiobiological modelisation and Biologically Effective Dose (BED) is principal related dosimetric quantity. Therefore, the consideration of BED-volume histogram (BED-VHs) is a straightforward extension of DVHs. In practice, BED-VHs can help relative comparisons and optimisations in treatment planning when combined to dose-volume histograms. Since 1994 the dosimetric calculations for all the gynecological brachytherapy treatments are performed considering also DVHs and BED-VHs. In this presentation we show the methods of BEDVHs calculation, together with some typical results

  17. Investigations on the necessity of dose calculations for several planes of the target volume

    International Nuclear Information System (INIS)

    Richter, E.

    1987-01-01

    In radiotherapy planning, the shape of a target volume can at present be exactly delimited by means of computed tomography. A method often applied is to project the largest target volume scan on the plane of the central ray and to calculate the dose in this plane. This method does not allow to take into account any change of the target volume scan which will be mainly due to the body contours of the patient. The results of dose calculations made in several planes for pharyngeal and laryngeal tumors are presented. With this procedure, 33 out of 60 irradiation techniques for nine tumor sites meet the requirements with regard to the central ray plane. If several planes are regarded, this is only true for ten irradiation plans. If is therefore absolutely necessary to calculate the doses of several planes if the target volume has an irregular shape or if the body contours vary considerably. This is the only way to prevent a false treatment caused by possibly severe dose excesses or dose insufficiencies in radiotherapy. (orig.) [de

  18. A method for bubble volume calculating in vertical two-phase flow

    International Nuclear Information System (INIS)

    Wang, H Y; Dong, F

    2009-01-01

    The movement of bubble is a basic subject in gas-liquid two-phase flow research. A method for calculating bubble volume which is one of the most important characters in bubble motion research was proposed. A suit of visualized experimental device was designed and set up. Single bubble rising in stagnant liquid in a rectangular tank was studied using the high-speed video system. Bubbles generated by four orifice with different diameter (1mm, 2mm, 3mm, 4mm) were recorded respectively. Sequences of recorded high-speed images were processed by digital image processing method, such as image noise remove, binary image transform, bubble filling, and so on. then, Several parameters could be obtained from the processed image. Bubble area, equivalent diameter, bubble velocity, bubble acceleration are all indispensable in bubble volume calculating. In order to get the force balance equation, forces that work on bubble along vertical direction, including drag force, virtual mass force, buoyancy, gravity and liquid thrust, were analyzed. Finally, the bubble volume formula could be derived from the force balance equation and bubble parameters. Examples were given to shown the computing process and results. Comparison of the bubble volume calculated by geomettic method and the present method have shown the superiority of the proposed method in this paper.

  19. Influence of the choice of parameters of the TAC in the calculation of volumes for different planners

    International Nuclear Information System (INIS)

    Sanchez Mazon, J.; Raba Diez, J. L.; Vazquez Rodriguez, J. A.; Pacheco Baldor, M. T.; Mendiguren Santiago, M. A.

    2011-01-01

    In the Protocol for the control treatment planning systems with ionizing radiation of the proposed SEFM tests to verify proper operation of the calculation in the evaluation of DVH (Dose Volume Histogram). The calculation of the volume that makes a planner may have important implications because it can trigger an overestimation of the dose or otherwise. We present a comparison of the calculation of volumes estimated with 4 different planners.

  20. Impact of endobronchial coiling on segmental bronchial lumen in treated and untreated lung lobes: Correlation with changes in lung volume, clinical and pulmonary function tests.

    Science.gov (United States)

    Kloth, C; Thaiss, W M; Hetzel, J; Ditt, H; Grosse, U; Nikolaou, K; Horger, M

    2016-07-01

    To assess the impact of endobronchial coiling on the segment bronchus cross-sectional area and volumes in patients with lung emphysema using quantitative chest-CT measurements. Thirty patients (female = 15; median age = 65.36 years) received chest-CT before and after endobronchial coiling for lung volume reduction (LVR) between January 2010 and December 2014. Thin-slice (0.6 mm) non-enhanced image data sets were acquired both at end-inspiration and end-expiration using helical technique and 120 kV/100-150 mAs. Clinical response was defined as an increase in the walking distance (Six-minute walk test; 6MWT) after LVR-therapy. Additionally, pulmonary function test (PFT) measurements were used for clinical correlation. In the treated segmental bronchia, the cross-sectional lumen area showed significant reduction (p  0.05). In the ipsilateral lobes, the lumina showed no significant changes. In the contralateral lung, we found tendency towards increased cross-sectional area in inspiration (p = 0.06). Volumes of the treated segments correlated with the treated segmental bronchial lumina in expiration (r = 0.80, p volume of the treated lobe in responders only. Endobronchial coiling causes significant decrease in the cross-sectional area of treated segment bronchi in inspiration and a slight increase in expiration accompanied by a volume reduction. • Endobronchial coiling has indirect impact on cross-sectional area of treated segment bronchi • Volume changes of treated lobes correlate with changes in bronchial cross-sectional area • Coil-induced effects reflect their stabilizing and stiffening impact on lung parenchyma • Endobronchial coiling reduces bronchial collapsing compensating the loss of elasticity.

  1. Biologic lung volume reduction in advanced upper lobe emphysema: phase 2 results.

    Science.gov (United States)

    Criner, Gerard J; Pinto-Plata, Victor; Strange, Charlie; Dransfield, Mark; Gotfried, Mark; Leeds, William; McLennan, Geoffrey; Refaely, Yael; Tewari, Sanjiv; Krasna, Mark; Celli, Bartolome

    2009-05-01

    Biologic lung volume reduction (BioLVR) is a new endobronchial treatment for advanced emphysema that reduces lung volume through tissue remodeling. Assess the safety and therapeutic dose of BioLVR hydrogel in upper lobe predominant emphysema. Open-labeled, multicenter phase 2 dose-ranging studies were performed with BioLVR hydrogel administered to eight subsegmental sites (four in each upper lobe) involving: (1) low-dose treatment (n = 28) with 10 ml per site (LD); and (2) high-dose treatment (n = 22) with 20 ml per site (HD). Safety was assessed by the incidence of serious medical complications. Efficacy was assessed by change from baseline in pulmonary function tests, dyspnea score, 6-minute walk distance, and health-related quality of life. After treatment there were no deaths and four serious treatment-related complications. A reduction in residual volume to TLC ratio at 12 weeks (primary efficacy outcome) was achieved with both LD (-6.4 +/- 9.3%; P = 0.002) and HD (-5.5 +/- 9.4%; P = 0.028) treatments. Improvements in pulmonary function in HD (6 mo: DeltaFEV(1) = +15.6%; P = 0.002; DeltaFVC = +9.1%; P = 0.034) were greater than in LD patients (6 mo: DeltaFEV(1) = +6.7%; P = 0.021; DeltaFVC = +5.1%; P = 0.139). LD- and HD-treated groups both demonstrated improved symptom scores and health-related quality of life. BioLVR improves physiology and functional outcomes up to 6 months with an acceptable safety profile in upper lobe predominant emphysema. Overall improvement was greater and responses more durable with 20 ml per site than 10 ml per site dosing. Clinical trial registered with www.clinicaltrials.gov (NCT 00435253 and NCT 00515164).

  2. Paradigm shift in LUNG SBRT dose calculation associated with Heterogeneity correction; Cambio de paradigma en SBRT pulmonar asociada al calculo de dosis con correccion de heterogeneidad

    Energy Technology Data Exchange (ETDEWEB)

    Zucca Aparicio, D.; Perez Moreno, J. M.; Fernandez Leton, P.; Garcia Ruiz-Zorrilla, J.; Pinto Monedero, M.; Marti Asensjo, J.; Alonso Iracheta, L.

    2015-07-01

    Treatment of lung injury SBRT requires great dosimetric accuracy, the increasing clinical importance of dose calculation heterogeneities introducing algorithms that adequately model the transport of particles narrow beams in media of low density, as with Monte Carlo calculation. (Author)

  3. Factors affecting volume calculation with single photon emission tomography (SPECT) method

    International Nuclear Information System (INIS)

    Liu, T.H.; Lee, K.H.; Chen, D.C.P.; Ballard, S.; Siegel, M.E.

    1985-01-01

    Several factors may influence the calculation of absolute volumes (VL) from SPECT images. The effect of these factors must be established to optimize the technique. The authors investigated the following on the VL calculations: % of background (BG) subtraction, reconstruction filters, sample activity, angular sampling and edge detection methods. Transaxial images of a liver-trunk phantom filled with Tc-99m from 1 to 3 μCi/cc were obtained in 64x64 matrix with a Siemens Rota Camera and MDS computer. Different reconstruction filters including Hanning 20,32, 64 and Butterworth 20, 32 were used. Angular samplings were performed in 3 and 6 degree increments. ROI's were drawn manually and with an automatic edge detection program around the image after BG subtraction. VL's were calculated by multiplying the number of pixels within the ROI by the slice thickness and the x- and y- calibrations of each pixel. One or 2 pixel per slice thickness was applied in the calculation. An inverse correlation was found between the calculated VL and the % of BG subtraction (r=0.99 for 1,2,3 μCi/cc activity). Based on the authors' linear regression analysis, the correct liver VL was measured with about 53% BG subtraction. The reconstruction filters, slice thickness and angular sampling had only minor effects on the calculated phantom volumes. Detection of the ROI automatically by the computer was not as accurate as the manual method. The authors conclude that the % of BG subtraction appears to be the most important factor affecting the VL calculation. With good quality control and appropriate reconstruction factors, correct VL calculations can be achieved with SPECT

  4. New conformity indices based on the calculation of distances between the target volume and the volume of reference isodose

    Science.gov (United States)

    Park, J M; Park, S-Y; Ye, S-J; Kim, J H; Carlson, J

    2014-01-01

    Objective: To present conformity indices (CIs) based on the distance differences between the target volume (TV) and the volume of reference isodose (VRI). Methods: The points on the three-dimensional surfaces of the TV and the VRI were generated. Then, the averaged distances between the points on the TV and the VRI were calculated (CIdistance). The performance of the presented CIs were evaluated by analysing six situations, which were a perfect match, an expansion and a reduction of the distance from the centroid to the VRI compared with the distance from the centroid to the TV by 10%, a lateral shift of the VRI by 3 cm, a rotation of the VRI by 45° and a spherical-shaped VRI having the same volume as the TV. The presented CIs were applied to the clinical prostate and head and neck (H&N) plans. Results: For the perfect match, CIdistance was 0 with 0 as the standard deviation (SD). When expanding and reducing, CIdistance was 10 and −10 with SDs 11. The average value of the CIdistance in the prostate and H&N plans was 0.13 ± 7.44 and 6.04 ± 23.27, respectively. Conclusion: The performance of the CIdistance was equal or better than those of the conventional CIs. Advances in knowledge: The evaluation of target conformity by the distances between the surface of the TV and the VRI could be more accurate than evaluation with volume information. PMID:25225915

  5. Expanding the calculation of activation volumes: Self-diffusion in liquid water

    Science.gov (United States)

    Piskulich, Zeke A.; Mesele, Oluwaseun O.; Thompson, Ward H.

    2018-04-01

    A general method for calculating the dependence of dynamical time scales on macroscopic thermodynamic variables from a single set of simulations is presented. The approach is applied to the pressure dependence of the self-diffusion coefficient of liquid water as a particularly useful illustration. It is shown how the activation volume associated with diffusion can be obtained directly from simulations at a single pressure, avoiding approximations that are typically invoked.

  6. The (water + acetonitrile) mixture revisited: A new approach for calculating partial molar volumes

    International Nuclear Information System (INIS)

    Carmen Grande, Maria del; Julia, Jorge Alvarez; Barrero, Carmen R.; Marschoff, Carlos M.; Bianchi, Hugo L.

    2006-01-01

    Density and viscosity of (water + acetonitrile) mixtures were measured over the whole composition range at the temperatures: (298.15, 303.15, 308.15, 313.15, and 318.15) K. A new mathematical approach was developed which allows the calculation of the derivatives of density with respect to composition avoiding the appearance of local discontinuities. Thus, reliable partial molar volumes and thermal expansion coefficients were obtained

  7. Quantitative gated SPECT: the effect of reconstruction filter on calculated left ventricular ejection fractions and volumes

    International Nuclear Information System (INIS)

    Wright, Graham A.; McDade, Mark; Martin, William; Hutton, William

    2002-01-01

    Gated SPECT (GSPECT) offers the possibility of obtaining additional functional information from perfusion studies, including calculation of left ventricular ejection fraction (LVEF). The calculation of LVEF relies upon the identification of the endocardial surface, which will be affected by the spatial resolution and statistical noise in the reconstructed images. The aim of this study was to compare LVEFs and ventricular volumes calculated from GSPECT using six reconstruction filters. GSPECT and radionuclide ventriculography (RNVG) were performed on 40 patients; filtered back projection was used to reconstruct the datasets with each filter. LVEFs and volumes were calculated using the Cedars-Sinai QGS package. The correlation coefficient between RNVG and GSPECT ranged from 0.81 to 0.86 with higher correlations for smoother filters. The narrowest prediction interval was 11±2%. There was a trend towards higher LVEF values with smoother filters, the ramp filter yielding LVEFs 2.55±3.10% (p<0.001) lower than the Hann filter. There was an overall fall in ventricular volumes with smoother filters with a mean difference of 13.98±10.15 ml (p<0.001) in EDV between the Butterworth-0.5 and Butterworth-0.3 filters. In conclusion, smoother reconstruction filters lead to lower volumes and higher ejection fractions with the QGS algorithm, with the Butterworth-0.4 filter giving the highest correlation with LVEFs from RNVG. Even if the optimal filter is chosen the uncertainty in the measured ejection fractions is still too great to be clinically acceptable. (author)

  8. Waste Retrieval Sluicing System Campaign Number 3 Solids Volume Transferred Calculation

    International Nuclear Information System (INIS)

    CAROTHERS, K.G.

    1999-01-01

    Waste Retrieval Sluicing System (WRSS) operations at tank 241-C-106 began on Wednesday, November 18, 1998. The purpose of this system is to retrieve and transfer the high-heat sludge from the tank for storage in double-shell tank 241-AY-102, thereby resolving the high-heat safety issue for the tank, and to demonstrate modernized past-practice retrieval technology for single-shell tank waste. Performance Agreement (PA) TWR 1.2.2, C-106 Sluicing, was established by the Department of Energy, Office of River Protection (ORP) for achieving completion of sluicing retrieval of waste from tank 241-C-106 by September 30, 1999. This level of sludge removal is defined in the PA as either removal of approximately 72 inches of sludge or removal of 172,000 gallons of sludge (approximately 62 inches) and less than 6,000 gallons (approximately 2 inches) of sludge removal per 12 hour sluice batch for three consecutive batches. Preliminary calculations of the volume of tank 241-C-106 sludge removed as of September 29, 1999 were provided to ORP documenting completion of PA TWR 1.2.2 (Allen 1999a). The purpose of this calculation is to document the final sludge volume removed from tank 241-C-106 up through September 30, 1999. Additionally, the results of an extra batch completed October 6, 1999 is included to show the total volume of sludge removed through the end of WRSS operations. The calculation of the sludge volume transferred from the tank is guided by engineering procedure HNF-SD-WM-PROC-021, Section 15.0,Rev. 3, sub-section 4.4, ''Calculation of Sludge Transferred.''

  9. W-320 waste retrieval sluicing system transfer line flushing volume and frequency calculation

    International Nuclear Information System (INIS)

    Bailey, J.W.

    1997-01-01

    The calculations contained in this analysis document establish the technical basis for the volume, frequency, and flushing fluid to be utilized for routine Waste Retrieval Sluicing System (WRSS) process line flushes. The WRSS was installed by Project W-320, Tank 241-C-106 Sluicing. The double contained pipelines being flushed have 4 inch stainless steel primary pipes. The flushes are intended to prevent hydrogen buildup in the transfer lines and to provide ALARA conditions for maintenance personnel

  10. Waste Retrieval Sluicing System Campaign Number 3 Solids Volume Transferred Calculation

    International Nuclear Information System (INIS)

    CAROTHERS, K.G.

    1999-01-01

    Waste Retrieval Sluicing System (WRSS) operations at tank 241-C-106 began on Wednesday, November 18,1998. The purpose of this system is to retrieve and transfer the high-heat sludge from the tank for storage in double-shell tank 241-AY-102, thereby resolving the high-heat safety issue for the tank, and to demonstrate modernized past-practice retrieval technology for single-shell tank waste. Performance Agreement (PA) TWR 1.2.2, C-106 Sluicing, was established by the Department of Energy, Office of River Protection (ORP) for achieving completion of sluicing retrieval of waste from tank 241-C-106 by September 30,1999. This level of sludge removal is defined in the PA as either removal of approximately 72 inches of sludge or removal of 172,000 gallons of sludge (approximately 62 inches) and less than 6,000 gallons (approximately 2 inches) of sludge removal per 12 hour sluice batch for three consecutive batches. Preliminary calculations of the volume of tank 241-C-106 sludge removed as of September 29, 1999 were provided to ORP documenting completion of PA TWR 1.2.2 (Allen 1999a). The purpose of this calculation is to document the final sludge volume removed from tank 241-C-106 up through September 30, 1999. Additionally, the results of an extra batch completed October 6, 1999 is included to show the total volume of sludge removed through the end of WRSS operations. The calculation of the sludge volume transferred from the tank is guided by engineering procedure HNF-SD-WM-PROC-021, Section 15.0,Rev. 3, sub-section 4.4, ''Calculation of Sludge Transferred.''

  11. IMRT: Improvement in treatment planning efficiency using NTCP calculation independent of the dose-volume-histogram

    International Nuclear Information System (INIS)

    Grigorov, Grigor N.; Chow, James C.L.; Grigorov, Lenko; Jiang, Runqing; Barnett, Rob B.

    2006-01-01

    The normal tissue complication probability (NTCP) is a predictor of radiobiological effect for organs at risk (OAR). The calculation of the NTCP is based on the dose-volume-histogram (DVH) which is generated by the treatment planning system after calculation of the 3D dose distribution. Including the NTCP in the objective function for intensity modulated radiation therapy (IMRT) plan optimization would make the planning more effective in reducing the postradiation effects. However, doing so would lengthen the total planning time. The purpose of this work is to establish a method for NTCP determination, independent of a DVH calculation, as a quality assurance check and also as a mean of improving the treatment planning efficiency. In the study, the CTs of ten randomly selected prostate patients were used. IMRT optimization was performed with a PINNACLE3 V 6.2b planning system, using planning target volume (PTV) with margins in the range of 2 to 10 mm. The DVH control points of the PTV and OAR were adapted from the prescriptions of Radiation Therapy Oncology Group protocol P-0126 for an escalated prescribed dose of 82 Gy. This paper presents a new model for the determination of the rectal NTCP ( R NTCP). The method uses a special function, named GVN (from Gy, Volume, NTCP), which describes the R NTCP if 1 cm 3 of the volume of intersection of the PTV and rectum (R int ) is irradiated uniformly by a dose of 1 Gy. The function was 'geometrically' normalized using a prostate-prostate ratio (PPR) of the patients' prostates. A correction of the R NTCP for different prescribed doses, ranging from 70 to 82 Gy, was employed in our model. The argument of the normalized function is the R int , and parameters are the prescribed dose, prostate volume, PTV margin, and PPR. The R NTCPs of another group of patients were calculated by the new method and the resulting difference was <±5% in comparison to the NTCP calculated by the PINNACLE3 software where Kutcher's dose

  12. Calculated volumes of individual shield volcanoes at the young end of the Hawaiian Ridge

    Science.gov (United States)

    Robinson, Joel E.; Eakins, Barry W.

    2006-03-01

    High-resolution multibeam bathymetry and a digital elevation model of the Hawaiian Islands are used to calculate the volumes of individual shield volcanoes and island complexes (Niihau, Kauai, Oahu, the Maui Nui complex, and Hawaii), taking into account subsidence of the Pacific plate under the load of the Hawaiian Ridge. Our calculated volume for the Island of Hawaii and its submarine extent (213 × 10 3 km 3) is nearly twice the previous estimate (113 × 10 3 km 3), due primarily to crustal subsidence that had not been accounted for in the earlier work. The volcanoes that make up the Island of Hawaii (Mahukona, Kohala, Mauna Kea, Hualalai, Mauna Loa, Kilauea and Loihi) are generally considered to have been formed within the past million years, and our revised volume for the island indicates that magma supply rates are greater than previously estimated, 0.21 km 3/yr as opposed to ˜ 0.1 km 3/yr. This result also shows that compared with rates calculated for the Hawaiian Islands (0-6 Ma, 0.095 km 3/yr), the Hawaiian Ridge (0-45 Ma, 0.017 km 3/yr), and the Emperor Seamounts (45-80 Ma, 0.010 km 3/yr), magma supply rates have increased dramatically to build the Island of Hawaii.

  13. Uncertainty modelling and analysis of volume calculations based on a regular grid digital elevation model (DEM)

    Science.gov (United States)

    Li, Chang; Wang, Qing; Shi, Wenzhong; Zhao, Sisi

    2018-05-01

    The accuracy of earthwork calculations that compute terrain volume is critical to digital terrain analysis (DTA). The uncertainties in volume calculations (VCs) based on a DEM are primarily related to three factors: 1) model error (ME), which is caused by an adopted algorithm for a VC model, 2) discrete error (DE), which is usually caused by DEM resolution and terrain complexity, and 3) propagation error (PE), which is caused by the variables' error. Based on these factors, the uncertainty modelling and analysis of VCs based on a regular grid DEM are investigated in this paper. Especially, how to quantify the uncertainty of VCs is proposed by a confidence interval based on truncation error (TE). In the experiments, the trapezoidal double rule (TDR) and Simpson's double rule (SDR) were used to calculate volume, where the TE is the major ME, and six simulated regular grid DEMs with different terrain complexity and resolution (i.e. DE) were generated by a Gauss synthetic surface to easily obtain the theoretical true value and eliminate the interference of data errors. For PE, Monte-Carlo simulation techniques and spatial autocorrelation were used to represent DEM uncertainty. This study can enrich uncertainty modelling and analysis-related theories of geographic information science.

  14. Is the Ellipsoid Formula the New Standard for 3-Tesla MRI Prostate Volume Calculation without Endorectal Coil?

    Science.gov (United States)

    Haas, Matthias; Günzel, Karsten; Miller, Kurt; Hamm, Bernd; Cash, Hannes; Asbach, Patrick

    2017-01-01

    Prostate volume in multiparametric MRI (mpMRI) is of clinical importance. For 3-Tesla mpMRI without endorectal coil, there is no distinctive standard for volume calculation. We tested the accuracy of the ellipsoid formula with planimetric volume measurements as reference and investigated the correlation of gland volume and cancer detection rate on MRI/ultrasound (MRI/US) fusion-guided biopsy. One hundred forty-three patients with findings on 3-Tesla mpMRI suspicious of cancer and subsequent MRI/US fusion-guided targeted biopsy and additional systematic biopsy were analyzed. T2-weighted images were used for measuring the prostate diameters and for planimetric volume measurement by a segmentation software. Planimetric and calculated prostate volumes were compared with clinical data. The median prostate volume was 48.1 ml (interquartile range (IQR) 36.9-62.1 ml). Volume calculated by the ellipsoid formula showed a strong concordance with planimetric volume, with a tendency to underestimate prostate volume (median volume 43.1 ml (IQR 31.2-58.8 ml); r = 0.903, p Tesla mpMRI without endorectal coil. It allows a fast, valid volume calculation in prostate MRI datasets. © 2016 S. Karger AG, Basel.

  15. Pulmonary compliance and lung volume varies with ecomorphology in anuran amphibians: implications for ventilatory-assisted lymph flux.

    Science.gov (United States)

    Hedrick, Michael S; Hillman, Stanley S; Drewes, Robert C; Withers, Philip C

    2011-10-01

    Vertical movement of lymph from ventral regions to the dorsally located lymph hearts in anurans is accomplished by specialized skeletal muscles working in concert with lung ventilation. We hypothesize that more terrestrial species with greater lymph mobilization capacities and higher lymph flux rates will have larger lung volumes and higher pulmonary compliance than more semi-aquatic or aquatic species. We measured in situ mean and maximal compliance (Δvolume/Δpressure), distensibility (%Δvolume/Δpressure) and lung volume over a range of physiological pressures (1.0 to 4.0 cmH(2)O) for nine species of anurans representing three families (Bufonide, Ranidae and Pipidae) that span a range of body masses and habitats from terrestrial to aquatic. We further examined the relationship between these pulmonary variables and lymph flux for a semi-terrestrial bufonid (Rhinella marina), a semi-aquatic ranid (Lithobates catesbeianus) and an aquatic pipid (Xenopus laevis). Allometric scaling of pulmonary compliance and lung volume with body mass showed significant differences at the family level, with scaling exponents ranging from ∼0.75 in Bufonidae to ∼1.3 in Pipidae. Consistent with our hypothesis, the terrestrial Bufonidae species had significantly greater pulmonary compliance and greater lung volumes compared with semi-aquatic Ranidae and aquatic Pipidae species. Pulmonary distensibility ranged from ∼20 to 35% cmH(2)O(-1) for the three families but did not correlate with ecomorphology. For the three species for which lymph flux data are available, R. marina had a significantly higher (Pvolume (242.1±5.5 ml kg(-1)) compared with L. catesbeianus (54.5±0.12 ml cmH(2)O(-1) kg(-1) and 139.3±0.5 ml kg(-1)) and X. laevis (30.8±0.7 ml cmH(2)O(-1) kg(-1) and 61.3±2.5 ml kg(-1)). Lymph flux rates were also highest for R. marina, lowest for X. laevis and intermediate in L. catesbeianus. Thus, there is a strong correlation between pulmonary compliance, lung volume and

  16. Accuracy of near-patient vs. inbuilt spirometry for monitoring tidal volumes in an in-vitro paediatric lung model.

    Science.gov (United States)

    Morgenroth, S; Thomas, J; Cannizzaro, V; Weiss, M; Schmidt, A R

    2018-03-01

    Spirometric monitoring provides precise measurement and delivery of tidal volumes within a narrow range, which is essential for lung-protective strategies that aim to reduce morbidity and mortality in mechanically-ventilated patients. Conventional anaesthesia ventilators include inbuilt spirometry to monitor inspiratory and expiratory tidal volumes. The GE Aisys CS 2 anaesthesia ventilator allows additional near-patient spirometry via a sensor interposed between the proximal end of the tracheal tube and the respiratory tubing. Near-patient and inbuilt spirometry of two different GE Aisys CS 2 anaesthesia ventilators were compared in an in-vitro study. Assessments were made of accuracy and variability in inspiratory and expiratory tidal volume measurements during ventilation of six simulated paediatric lung models using the ASL 5000 test lung. A total of 9240 breaths were recorded and analysed. Differences between inspiratory tidal volumes measured with near-patient and inbuilt spirometry were most significant in the newborn setting (p tidal volume measurements with near-patient spirometry were consistently more accurate than with inbuilt spirometry for all lung models (p tidal volumes decreased with increasing tidal volumes, and was smaller with near-patient than with inbuilt spirometry. The variability in measured tidal volumes was higher during expiration, especially with inbuilt spirometry. In conclusion, the present in-vitro study shows that measurements with near-patient spirometry are more accurate and less variable than with inbuilt spirometry. Differences between measurement methods were most significant in the smallest patients. We therefore recommend near-patient spirometry, especially for neonatal and paediatric patients. © 2018 The Association of Anaesthetists of Great Britain and Ireland.

  17. Adjusting tidal volume to stress index in an open lung condition optimizes ventilation and prevents overdistension in an experimental model of lung injury and reduced chest wall compliance.

    Science.gov (United States)

    Ferrando, Carlos; Suárez-Sipmann, Fernando; Gutierrez, Andrea; Tusman, Gerardo; Carbonell, Jose; García, Marisa; Piqueras, Laura; Compañ, Desamparados; Flores, Susanie; Soro, Marina; Llombart, Alicia; Belda, Francisco Javier

    2015-01-13

    The stress index (SI), a parameter derived from the shape of the pressure-time curve, can identify injurious mechanical ventilation. We tested the hypothesis that adjusting tidal volume (VT) to a non-injurious SI in an open lung condition avoids hypoventilation while preventing overdistension in an experimental model of combined lung injury and low chest-wall compliance (Ccw). Lung injury was induced by repeated lung lavages using warm saline solution, and Ccw was reduced by controlled intra-abdominal air-insufflation in 22 anesthetized, paralyzed and mechanically ventilated pigs. After injury animals were recruited and submitted to a positive end-expiratory pressure (PEEP) titration trial to find the PEEP level resulting in maximum compliance. During a subsequent four hours of mechanical ventilation, VT was adjusted to keep a plateau pressure (Pplat) of 30 cmH2O (Pplat-group, n = 11) or to a SI between 0.95 and 1.05 (SI-group, n = 11). Respiratory rate was adjusted to maintain a 'normal' PaCO2 (35 to 65 mmHg). SI, lung mechanics, arterial-blood gases haemodynamics pro-inflammatory cytokines and histopathology were analyzed. In addition Computed Tomography (CT) data were acquired at end expiration and end inspiration in six animals. PaCO2 was significantly higher in the Pplat-group (82 versus 53 mmHg, P = 0.01), with a resulting lower pH (7.19 versus 7.34, P = 0.01). We observed significant differences in VT (7.3 versus 5.4 mlKg(-1), P = 0.002) and Pplat values (30 versus 35 cmH2O, P = 0.001) between the Pplat-group and SI-group respectively. SI (1.03 versus 0.99, P = 0.42) and end-inspiratory transpulmonary pressure (PTP) (17 versus 18 cmH2O, P = 0.42) were similar in the Pplat- and SI-groups respectively, without differences in overinflated lung areas at end- inspiration in both groups. Cytokines and histopathology showed no differences. Setting tidal volume to a non-injurious stress index in an open lung condition improves

  18. Lung volume recruitment acutely increases respiratory system compliance in individuals with severe respiratory muscle weakness

    Directory of Open Access Journals (Sweden)

    Yannick Molgat-Seon

    2017-03-01

    Full Text Available The aim of the present study was to determine whether lung volume recruitment (LVR acutely increases respiratory system compliance (Crs in individuals with severe respiratory muscle weakness (RMW. Individuals with RMW resulting from neuromuscular disease or quadriplegia (n=12 and healthy controls (n=12 underwent pulmonary function testing and the measurement of Crs at baseline, immediately after, 1 h after and 2 h after a single standardised session of LVR. The LVR session involved 10 consecutive supramaximal lung inflations with a manual resuscitation bag to the highest tolerable mouth pressure or a maximum of 50 cmH2O. Each LVR inflation was followed by brief breath-hold and a maximal expiration to residual volume. At baseline, individuals with RMW had lower Crs than controls (37±5 cmH2O versus 109±10 mL·cmH2O−1, p0.05. LVR had no significant effect on measures of pulmonary function at any time point in either group (all p>0.05. During inflations, mean arterial pressure decreased significantly relative to baseline by 10.4±2.8 mmHg and 17.3±3.0 mmHg in individuals with RMW and controls, respectively (both p<0.05. LVR acutely increases Crs in individuals with RMW. However, the high airway pressures during inflations cause reductions in mean arterial pressure that should be considered when applying this technique.

  19. Influence of heart failure on resting lung volumes in patients with COPD.

    Science.gov (United States)

    Souza, Aline Soares de; Sperandio, Priscila Abreu; Mazzuco, Adriana; Alencar, Maria Clara; Arbex, Flávio Ferlin; Oliveira, Mayron Faria de; O'Donnell, Denis Eunan; Neder, José Alberto

    2016-01-01

    To evaluate the influence of chronic heart failure (CHF) on resting lung volumes in patients with COPD, i.e., inspiratory fraction-inspiratory capacity (IC)/TLC-and relative inspiratory reserve-[1 - (end-inspiratory lung volume/TLC)]. This was a prospective study involving 56 patients with COPD-24 (23 males/1 female) with COPD+CHF and 32 (28 males/4 females) with COPD only-who, after careful clinical stabilization, underwent spirometry (with forced and slow maneuvers) and whole-body plethysmography. Although FEV1, as well as the FEV1/FVC and FEV1/slow vital capacity ratios, were higher in the COPD+CHF group than in the COPD group, all major "static" volumes-RV, functional residual capacity (FRC), and TLC-were lower in the former group (p grupo DPOC+ICC; 23 homens/1 mulher) e 32 (28 homens/4 mulheres) com DPOC isolada foram submetidos à espirometria forçada e lenta e pletismografia de corpo inteiro. Os pacientes do grupo DPOC+ICC apresentaram maior VEF1, VEF1/CVF e VEF1/capacidade vital lenta; porém, todos os principais volumes "estáticos" - VR, capacidade residual funcional (CRF) e CPT - foram menores que aqueles do grupo DPOC (p grupo DPOC+ICC que no grupo DPOC. Houve redução relativamente proporcional da CRF e da CPT nos dois grupos; logo, a CI também foi similar. Consequentemente, a fração inspiratória no grupo DPOC+ICC foi maior que no grupo DPOC (0,42 ± 0,10 vs. 0,36 ± 0,10; p grupo DPOC+ICC, a reserva inspiratória relativa foi notadamente similar entre os grupos (0,35 ± 0,09 vs. 0,44 ± 0,14; p < 0,05). Apesar dos efeitos restritivos da ICC, pacientes com DPOC+ICC apresentam elevações relativas dos limites inspiratórios (maior fração inspiratória). Entretanto, esses pacientes utilizam apenas parte desses limites, com o provável intuito de evitar reduções críticas da reserva inspiratória e maior trabalho elástico.

  20. Performance of Leak Compensation in All-Age ICU Ventilators During Volume-Targeted Neonatal Ventilation: A Lung Model Study.

    Science.gov (United States)

    Itagaki, Taiga; Bennett, Desmond J; Chenelle, Christopher T; Fisher, Daniel F; Kacmarek, Robert M

    2017-01-01

    Volume-targeted ventilation is increasingly used in low birthweight infants because of the potential for reducing volutrauma and avoiding hypocapnea. However, it is not known what level of air leak is acceptable during neonatal volume-targeted ventilation when leak compensation is activated concurrently. Four ICU ventilators (Servo-i, PB980, V500, and Avea) were compared in available invasive volume-targeted ventilation modes (pressure control continuous spontaneous ventilation [PC-CSV] and pressure control continuous mandatory ventilation [PC-CMV]). The Servo-i and PB980 were tested with (+) and without (-) their proximal flow sensor. The V500 and Avea were tested with their proximal flow sensor as indicated by their manufacturers. An ASL 5000 lung model was used to simulate 4 neonatal scenarios (body weight 0.5, 1, 2, and 4 kg). The ASL 5000 was ventilated via an endotracheal tube with 3 different leaks. Two minutes of data were collected after each change in leak level, and the asynchrony index was calculated. Tidal volume (V T ) before and after the change in leak was assessed. The differences in delivered V T between before and after the change in leak were within ±5% in all scenarios with the PB980 (-/+) and V500. With the Servo-i (-/+), baseline V T was ≥10% greater than set V T during PC-CSV, and delivered V T markedly changed with leak. The Avea demonstrated persistent high V T in all leak scenarios. Across all ventilators, the median asynchrony index was 1% (interquartile range 0-27%) in PC-CSV and 1.8% (0-45%) in PC-CMV. The median asynchrony index was significantly higher in the Servo-i (-/+) than in the PB980 (-/+) and V500 in 1 and 2 kg scenarios during PC-CSV and PC-CMV. The PB980 and V500 were the only ventilators to acclimate to all leak scenarios and achieve targeted V T . Further clinical investigation is needed to validate the use of leak compensation during neonatal volume-targeted ventilation. Copyright © 2017 by Daedalus Enterprises.

  1. Low tidal volume ventilation ameliorates left ventricular dysfunction in mechanically ventilated rats following LPS-induced lung injury.

    Science.gov (United States)

    Cherpanath, Thomas G V; Smeding, Lonneke; Hirsch, Alexander; Lagrand, Wim K; Schultz, Marcus J; Groeneveld, A B Johan

    2015-10-07

    High tidal volume ventilation has shown to cause ventilator-induced lung injury (VILI), possibly contributing to concomitant extrapulmonary organ dysfunction. The present study examined whether left ventricular (LV) function is dependent on tidal volume size and whether this effect is augmented during lipopolysaccharide(LPS)-induced lung injury. Twenty male Wistar rats were sedated, paralyzed and then randomized in four groups receiving mechanical ventilation with tidal volumes of 6 ml/kg or 19 ml/kg with or without intrapulmonary administration of LPS. A conductance catheter was placed in the left ventricle to generate pressure-volume loops, which were also obtained within a few seconds of vena cava occlusion to obtain relatively load-independent LV systolic and diastolic function parameters. The end-systolic elastance / effective arterial elastance (Ees/Ea) ratio was used as the primary parameter of LV systolic function with the end-diastolic elastance (Eed) as primary LV diastolic function. Ees/Ea decreased over time in rats receiving LPS (p = 0.045) and high tidal volume ventilation (p = 0.007), with a lower Ees/Ea in the rats with high tidal volume ventilation plus LPS compared to the other groups (p tidal volume ventilation without LPS (p = 0.223). A significant interaction (p tidal ventilation and LPS for Ees/Ea and Eed, and all rats receiving high tidal volume ventilation plus LPS died before the end of the experiment. Low tidal volume ventilation ameliorated LV systolic and diastolic dysfunction while preventing death following LPS-induced lung injury in mechanically ventilated rats. Our data advocates the use of low tidal volumes, not only to avoid VILI, but to avert ventilator-induced myocardial dysfunction as well.

  2. Impact of obstructive sleep apnea on lung volumes and mechanical properties of the respiratory system in overweight and obese individuals.

    Science.gov (United States)

    Abdeyrim, Arikin; Zhang, Yongping; Li, Nanfang; Zhao, Minghua; Wang, Yinchun; Yao, Xiaoguang; Keyoumu, Youledusi; Yin, Ting

    2015-07-25

    Even through narrowing of the upper-airway plays an important role in the generation of obstructive sleep apnea (OSA), the peripheral airways is implicated in pre-obese and obese OSA patients, as a result of decreased lung volume and increased lung elastic recoil pressure, which, in turn, may aggravate upper-airway collapsibility. A total of 263 male (n = 193) and female (n = 70) subjects who were obese to various degrees without a history of lung diseases and an expiratory flow limitation, but troubled with snoring or suspicion of OSA were included in this cross-sectional study. According to nocturnal-polysomnography the subjects were distributed into OSA and non-OSA groups, and were further sub-grouped by gender because of differences between males and females, in term of, lung volume size, airway resistance, and the prevalence of OSA among genders. Lung volume and respiratory mechanical properties at different-frequencies were evaluated by plethysmograph and an impulse oscillation system, respectively. Functional residual capacity (FRC) and expiratory reserve volume were significantly decreased in the OSA group compared to the non-OSA group among males and females. As weight and BMI in males in the OSA group were greater than in the non-OSA group (90 ± 14.8 kg vs. 82 ± 10.4 kg, p volumes decreases were independent from BMI and associated with the severity of OSA. This result was further confirmed by the female cohort. Significant increases in total respiratory resistance and decreases in respiratory conductance (Grs) were observed with increasing severity of OSA, as defined by the apnea-hypopnea index (AHI) in both genders. The specific Grs (sGrs) stayed relatively constant between the two groups in woman, and there was only a weak association between AHI and sGrs among man. Multiple-stepwise-regression showed that reactance at 5 Hz was highly correlated with AHI in males and females or hypopnea index in females, independently

  3. Effects of a Multidisciplinary Approach to Improve Volume of Diagnostic Material in CT-Guided Lung Biopsies.

    Science.gov (United States)

    Ferguson, Philip E; Sales, Catherine M; Hodges, Dalton C; Sales, Elizabeth W

    2015-01-01

    Recent publications have emphasized the importance of a multidisciplinary strategy for maximum conservation and utilization of lung biopsy material for advanced testing, which may determine therapy. This paper quantifies the effect of a multidisciplinary strategy implemented to optimize and increase tissue volume in CT-guided transthoracic needle core lung biopsies. The strategy was three-pronged: (1) once there was confidence diagnostic tissue had been obtained and if safe for the patient, additional biopsy passes were performed to further increase volume of biopsy material, (2) biopsy material was placed in multiple cassettes for processing, and (3) all tissue ribbons were conserved when cutting blocks in the histology laboratory. This study quantifies the effects of strategies #1 and #2. This retrospective analysis comparing CT-guided lung biopsies from 2007 and 2012 (before and after multidisciplinary approach implementation) was performed at a single institution. Patient medical records were reviewed and main variables analyzed include biopsy sample size, radiologist, number of blocks submitted, diagnosis, and complications. The biopsy sample size measured was considered to be directly proportional to tissue volume in the block. Biopsy sample size increased 2.5 fold with the average total biopsy sample size increasing from 1.0 cm (0.9-1.1 cm) in 2007 to 2.5 cm (2.3-2.8 cm) in 2012 (Pstrategy to CT-guided lung biopsies was effective in significantly increasing tissue volume and number of blocks available for advanced diagnostic testing.

  4. SU-F-T-415: Differences in Lung Sparing in Deep Inspiration Breath-Hold and Free Breathing Breast Plans Calculated in Pinnacle and Monaco

    Energy Technology Data Exchange (ETDEWEB)

    Saenz, D; Stathakis, S [University of Texas Health Science Center San Antonio, San Antonio, TX (United States)

    2016-06-15

    Purpose: Deep inspiration breath-hold (DIBH) is used for left-sided breast radiotherapy to spare the heart and lung. The magnitude of sparing has been shown to be significant. Monte Carlo, furthermore, has the potential to calculate most accurately the dose in the heterogeneous lung medium at the interface with the lung wall. The lung dose was investigated in Monaco to determine the level of sparing relative to that calculated in Pinnacle{sup 3}. Methods: Five patients undergoing DIBH radiotherapy on an Elekta Versa HD linear accelerator in conjunction with the Catalyst C-RAD surface imaging system were planned using Phillips Pinnacle{sup 3}. Free breathing plans were also created to clinically assure a benefit. Both plans were re-calculated in Monaco to determine if there were any significant differences. The mean heart dose, mean left lung, and mean total lung dose were compared in addition to the V20 for left and both lungs. Dose was calculated as dose to medium as well as dose to water with a statistical precision of 0.7%. Results: Mean lung dose was significantly different (p < 0.003) between the two calculations for both DIBH (11.6% higher in Monaco) and free breathing (14.2% higher in Monaco). V20 was also higher in Monaco (p < 0.05) for DIBH (5.7% higher) and free breathing (4.9% higher). The mean heart dose was not significantly different between the dose calculations for either DIBH or free breathing. Results were no more than 0.1% different when calculated as dose to water. Conclusion: The use of Monte Carlo can provide insight on the lung dose for both free breathing and DIBH techniques for whole breast irradiation. While the sparing (dose reductions with DIBH as compared to free breathing) is equivalent for either planning system, the lung doses themselves are higher when calculated with Monaco.

  5. Calculation of partial molar volume of components in supercritical ammonia synthesis system

    Institute of Scientific and Technical Information of China (English)

    Cunwen WANG; Chuanbo YU; Wen CHEN; Weiguo WANG; Yuanxin WU; Junfeng ZHANG

    2008-01-01

    The partial molar volumes of components in supercritical ammonia synthesis system are calculated in detail by the calculation formula of partial molar volume derived from the R-K equation of state under different conditions. The objectives are to comprehend phase beha-vior of components and to provide the theoretic explana-tion and guidance for probing novel processes of ammonia synthesis under supercritical conditions. The conditions of calculation are H2/N2= 3, at a concentra-tion of NH3 in synthesis gas ranging from 2% to 15%, Concentration of medium in supercritical ammonia syn-thesis system ranging from 20% to 50%, temperature ran-ging from 243 K to 699 K and pressure ranging from 0.1 MPa to 187 MPa. The results show that the ammonia synthesis system can reach supercritical state by adding a suitable supercritical medium and then controlling the reaction conditions. It is helpful for the supercritical ammonia synthesis that medium reaches supercritical state under the conditions of the corresponding total pres-sure and components near the normal temperature or near the critical temperature of medium or in the range of tem-perature of industrialized ammonia synthesis.

  6. Usage of Geoprocessing Services in Precision Forestry for Wood Volume Calculation and Wind Risk Assessment

    Directory of Open Access Journals (Sweden)

    Tomáš Mikita

    2015-01-01

    Full Text Available This paper outlines the idea of a precision forestry tool for optimizing clearcut size and shape within the process of forest recovery and its publishing in the form of a web processing service for forest owners on the Internet. The designed tool titled COWRAS (Clearcut Optimization and Wind Risk Assessment is developed for optimization of clearcuts (their location, shape, size, and orientation with subsequent wind risk assessment. The tool primarily works with airborne LiDAR data previously processed to the form of a digital surface model (DSM and a digital elevation model (DEM. In the first step, the growing stock on the planned clearcut determined by its location and area in feature class is calculated (by the method of individual tree detection. Subsequently tree heights from canopy height model (CHM are extracted and then diameters at breast height (DBH and wood volume using the regressions are calculated. Information about wood volume of each tree in the clearcut is exported and summarized in a table. In the next step, all trees in the clearcut are removed and a new DSM without trees in the clearcut is generated. This canopy model subsequently serves as an input for evaluation of wind risk damage by the MAXTOPEX tool (Mikita et al., 2012. In the final raster, predisposition of uncovered forest stand edges (around the clearcut to wind risk is calculated based on this analysis. The entire tool works in the background of ArcGIS server as a spatial decision support system for foresters.

  7. Intravenous superoxide dismutase as a protective agent to prevent impairment of lung function induced by high tidal volume ventilation.

    Science.gov (United States)

    Wu, Nan-Chun; Liao, Fan-Ting; Cheng, Hao-Min; Sung, Shih-Hsien; Yang, Yu-Chun; Wang, Jiun-Jr

    2017-07-26

    Positive-pressure mechanical ventilation is essential in assisting patients with respiratory failure in the intensive care unit and facilitating oxygenation in the operating room. However, it was also recognized as a primary factor leading to hospital-acquired pulmonary dysfunction, in which pulmonary oxidative stress and lung inflammation had been known to play important roles. Cu/Zn superoxide dismutase (SOD) is an important antioxidant, and possesses anti-inflammatory capacity. In this study, we aimed to study the efficacy of Cu/Zn SOD, administered intravenously during high tidal volume (HTV) ventilation, to prevent impairment of lung function. Thirty-eight male Sprague-Dawley rats were divided into 3 groups: 5 h ventilation with (A) low tidal volume (LTV; 8 mL/kg; n = 10), (B) high tidal volume (HTV; 18 mL/kg; n = 14), or (C) HTV and intravenous treatment of Cu/Zn SOD at a dose of 1000 U/kg/h (HTV + SOD; n = 14). Lung function was evaluated both at baseline and after 5-h ventilation. Lung injury was assessed by histological examination, lung water and protein contents in the bronchoalveolar lavage fluid (BALF). Pulmonary oxidative stress was examined by concentrations of methylguanidine (MG) and malondialdehyde (MDA) in BALF, and antioxidative activity by protein expression of glutathione peroxidase-1 (GPx-1) in the lung. Severity of lung inflammation was evaluated by white blood cell and differential count in BALF, and protein expression of inducible nitric oxide synthase (iNOS), intercellular adhesion molecule-1 (ICAM-1), tumor necrosis factor-α (TNF-α), matrix metalloproteinase-9 (MMP-9), and mRNA expression of nuclear factor-κB (NF-κB) in the lung. We also examined protein expression of surfactant protein (SP)-A and D and we measured hourly changes in serum nitric oxide (NO) level. Five hours of LTV ventilation did not induce a major change in lung function, whereas 5 h of HTV ventilation induced apparent combined restrictive and

  8. The Implementation of Cumulative Learning Theory in Calculating Triangular Prism and Tube Volumes

    Science.gov (United States)

    Muklis, M.; Abidin, C.; Pamungkas, M. D.; Masriyah

    2018-01-01

    This study aims at describing the application of cumulative learning theory in calculating the volume of a triangular prism and a tube as well as revealing the students’ responses toward the learning. The research method used was descriptive qualitative with elementary school students as the subjects of the research. Data obtained through observation, field notes, questionnaire, tests, and interviews. The results from the application of cumulative learning theory obtained positive students’ responses in following the learning and students’ learning outcomes was dominantly above the average. This showed that cumulative learning could be used as a reference to be implemented in learning, so as to improve the students’ achievement.

  9. Dose-volume histograms based on serial intravascular ultrasound: a calculation model for radioactive stents

    International Nuclear Information System (INIS)

    Kirisits, Christian; Wexberg, Paul; Gottsauner-Wolf, Michael; Pokrajac, Boris; Ortmann, Elisabeth; Aiginger, Hannes; Glogar, Dietmar; Poetter, Richard

    2001-01-01

    Background and purpose: Radioactive stents are under investigation for reduction of coronary restenosis. However, the actual dose delivered to specific parts of the coronary artery wall based on the individual vessel anatomy has not been determined so far. Dose-volume histograms (DVHs) permit an estimation of the actual dose absorbed by the target volume. We present a method to calculate DVHs based on intravascular ultrasound (IVUS) measurements to determine the dose distribution within the vessel wall. Materials and methods: Ten patients were studied by intravascular ultrasound after radioactive stenting (BX Stent, P-32, 15-mm length) to obtain tomographic cross-sections of the treated segments. We developed a computer algorithm using the actual dose distribution of the stent to calculate differential and cumulative DVHs. The minimal target dose, the mean target dose, the minimal doses delivered to 10 and 90% of the adventitia (DV10, DV90), and the percentage of volume receiving a reference dose at 0.5 mm from the stent surface cumulated over 28 days were derived from the DVH plots. Results were expressed as mean±SD. Results: The mean activity of the stents was 438±140 kBq at implantation. The mean reference dose was 111±35 Gy, whereas the calculated mean target dose within the adventitia along the stent was 68±20 Gy. On average, DV90 and DV10 were 33±9 Gy and 117±41 Gy, respectively. Expanding the target volume to include 2.5-mm-long segments at the proximal and distal ends of the stent, the calculated mean target dose decreased to 55±17 Gy, and DV 90 and DV 10 were 6.4±2.4 Gy and 107±36 Gy, respectively. Conclusions: The assessment of DVHs seems in principle to be a valuable tool for both prospective and retrospective analysis of dose-distribution of radioactive stents. It may provide the basis to adapt treatment planning in coronary brachytherapy to the common standards of radiotherapy

  10. The influence of homogenization on the calculation of the sensitivity volume of a BWR incore detector

    International Nuclear Information System (INIS)

    Haghighat, A.; Kosaly, G.

    1985-01-01

    By performing two-group, X-Y, S 4 transport theory calculations with the albedo boundary condition, the effect of heterogeneities on the BWR incore detector has been investigated. The albedo distribution along the boundary of the control volume is obtained using a two-group, homogenous, X-Y diffusion model. Different degrees of homogenization have been examined. Investigation shows that a cell-homogeneous model, with separated bypass region and inner water gap, is a viable alternative to the heterogeneous approach. This finding contradicts earlier predictions of a need for a heterogeneous model. (author)

  11. A Gaussian mixture model for definition of lung tumor volumes in positron emission tomography

    International Nuclear Information System (INIS)

    Aristophanous, Michalis; Penney, Bill C.; Martel, Mary K.; Pelizzari, Charles A.

    2007-01-01

    The increased interest in 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in radiation treatment planning in the past five years necessitated the independent and accurate segmentation of gross tumor volume (GTV) from FDG-PET scans. In some studies the radiation oncologist contours the GTV based on a computed tomography scan, while incorporating pertinent data from the PET images. Alternatively, a simple threshold, typically 40% of the maximum intensity, has been employed to differentiate tumor from normal tissue, while other researchers have developed algorithms to aid the PET based GTV definition. None of these methods, however, results in reliable PET tumor segmentation that can be used for more sophisticated treatment plans. For this reason, we developed a Gaussian mixture model (GMM) based segmentation technique on selected PET tumor regions from non-small cell lung cancer patients. The purpose of this study was to investigate the feasibility of using a GMM-based tumor volume definition in a robust, reliable and reproducible way. A GMM relies on the idea that any distribution, in our case a distribution of image intensities, can be expressed as a mixture of Gaussian densities representing different classes. According to our implementation, each class belongs to one of three regions in the image; the background (B), the uncertain (U) and the target (T), and from these regions we can obtain the tumor volume. User interaction in the implementation is required, but is limited to the initialization of the model parameters and the selection of an ''analysis region'' to which the modeling is restricted. The segmentation was developed on three and tested on another four clinical cases to ensure robustness against differences observed in the clinic. It also compared favorably with thresholding at 40% of the maximum intensity and a threshold determination function based on tumor to background image intensities proposed in a recent paper. The parts of the

  12. High frequency oscillatory ventilation with lung volume optimization in very low birth weight newborns – a nine-year experience

    Directory of Open Access Journals (Sweden)

    José Nona

    2009-09-01

    Full Text Available Objective: To evaluate the clinical outcome of very low birth weight newborns, submitted to high frequency oscillatory ventilation with a strategy of early lung volume optimization. Methods: Descriptive prospective study in a nine-year period, between 1999 January 1st to 2008 January 1st. All the very low birth weight newborns were born in Dr. Alfredo da Costa Maternity, Lisbon, Portugal, were admitted to the Neonatal Intensive Care Unit and submitted to high frequency oscillatory ventilation with early lung volume optimization; these newborns were followed-up since birth and their charts were analyzed periodically until hospital discharge. Rresults: From a total population of 730 very low birth weight inborns, 117 babies died (16% and 613 survived (84%. The median of birth weight was 975 g and the gestational age median was 28 weeks. For the survivors, the median ventilation and oxygenation times were 3 and 18 days, respectively. The incidence of chronic lung disease was 9.5%, with nine newborns discharged on oxygen therapy. The incidence of intraventricular hemorrhage III – IV (total population group was 11.5% and the incidence of retinopathy of prematurity grade 3 or higher was 8.0%. Cconclusions: High frequency oscillatory ventilation with early lung volume optimization strategy reduced the need of respiratory support, and improved pulmonary and global outcomes in very low birth weight infants with respiratory distress syndrome.

  13. [The importance of lung volumes in the investigation of heavy smokers].

    Science.gov (United States)

    Ben Saad, H; Ben Amor, L; Ben Mdalla, S; Ghannouchi, I; Ben Essghair, M; Sfaxi, R; Garrouche, A; Rouatbi, N; Rouatbi, S

    2014-01-01

    Lung hyperinflation (LH) has become a major concern in the management of chronic obstructive pulmonary disease (COPD). To evaluate the role of lung volumes in the positive diagnosis of COPD and in the assessment of airway obstruction reversibility. Three hundred and sixty-six male smokers over the age of 35 with more than 40 pack-years exposure were included in the study. Plethysmographic data were determined before/after taking a bronchodilator (BBD, ABD). Applied definitions: airflow obstruction: BBD FEV1/FVCvolume (RV)>upper limit of normal. Expressions of reversibility: Δvariable=(ABD-BBD) values; Δinit%=Δvariable/BBD value and Δref%=Δvariable/reference value. A 12%init and a 0.2L increase in either FEV1 or FVC or a 10%ref or - 300 mL decrease in RV were considered as clinically significant. Over the 85 smokers without airflow obstruction, 68% had LH. In the hyperinflated group (n=314), and compared to changes in FEV1 and FVC, these RV changes detected more respondents (54% for FEV1 and FVC vs. 65% for RV, P=0.002). This was not the case for the group free from LH (n=52) (23% for FEV1 and FVC vs. 35% for RV, P=0.09). In the 58 hyperinflated groups free from airflow obstruction, and compared to changes in FEV1 and FVC, changes in RV detected more respondents (24% for FEV1 and FVC vs. 71% for RV, P=0.0001). In heavy smokers, it seems essential to include LH as a criterion for a positive diagnosis of COPD and of reversibility evaluation. Copyright © 2013 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  14. Tidal Volume Single Breath Washout of Two Tracer Gases - A Practical and Promising Lung Function Test

    Science.gov (United States)

    Singer, Florian; Stern, Georgette; Thamrin, Cindy; Fuchs, Oliver; Riedel, Thomas; Gustafsson, Per; Frey, Urs; Latzin, Philipp

    2011-01-01

    Background Small airway disease frequently occurs in chronic lung diseases and may cause ventilation inhomogeneity (VI), which can be assessed by washout tests of inert tracer gas. Using two tracer gases with unequal molar mass (MM) and diffusivity increases specificity for VI in different lung zones. Currently washout tests are underutilised due to the time and effort required for measurements. The aim of this study was to develop and validate a simple technique for a new tidal single breath washout test (SBW) of sulfur hexafluoride (SF6) and helium (He) using an ultrasonic flowmeter (USFM). Methods The tracer gas mixture contained 5% SF6 and 26.3% He, had similar total MM as air, and was applied for a single tidal breath in 13 healthy adults. The USFM measured MM, which was then plotted against expired volume. USFM and mass spectrometer signals were compared in six subjects performing three SBW. Repeatability and reproducibility of SBW, i.e., area under the MM curve (AUC), were determined in seven subjects performing three SBW 24 hours apart. Results USFM reliably measured MM during all SBW tests (n = 60). MM from USFM reflected SF6 and He washout patterns measured by mass spectrometer. USFM signals were highly associated with mass spectrometer signals, e.g., for MM, linear regression r-squared was 0.98. Intra-subject coefficient of variation of AUC was 6.8%, and coefficient of repeatability was 11.8%. Conclusion The USFM accurately measured relative changes in SF6 and He washout. SBW tests were repeatable and reproducible in healthy adults. We have developed a fast, reliable, and straightforward USFM based SBW method, which provides valid information on SF6 and He washout patterns during tidal breathing. PMID:21423739

  15. Microbiological airway colonization in COPD patients with severe emphysema undergoing endoscopic lung volume reduction

    Directory of Open Access Journals (Sweden)

    Trudzinski FC

    2017-12-01

    Full Text Available Franziska C Trudzinski,1 Frederik Seiler,1 Heinrike Wilkens,1 Carlos Metz,1 Annegret Kamp,1 Robert Bals,1 Barbara Gärtner,2 Philipp M Lepper,1 Sören L Becker2–4 1Department of Internal Medicine V – Pneumology, Allergology and Critical Care Medicine, ECLS Center Saar, University Medical Center Saarland and Saarland University, 2Institute of Medical Microbiology and Hygiene, Saarland University, Homburg/Saar, Germany; 3Swiss Tropical and Public Health Institute, 4University of Basel, Basel, Switzerland Background: Endoscopic lung volume reduction (eLVR is a therapeutic option for selected patients with COPD and severe emphysema. Infectious exacerbations are serious events in these vulnerable patients; hence, prophylactic antibiotics are often prescribed postinterventionally. However, data on the microbiological airway colonization at the time of eLVR are scarce, and there are no evidence-based recommendations regarding a rational antibiotic regimen.Objective: The aim of this study was to perform a clinical and microbiological analysis of COPD patients with advanced emphysema undergoing eLVR with endobronchial valves at a single German University hospital, 2012–2017.Patients and methods: Bronchial aspirates were obtained prior to eLVR and sent for microbiological analysis. Antimicrobial susceptibility testing of bacterial isolates was performed, and pathogen colonization was retrospectively compared with clinical parameters.Results: At least one potential pathogen was found in 47% (30/64 of patients. Overall, Gram-negative bacteria constituted the most frequently detected pathogens. The single most prevalent species were Haemophilus influenzae (9%, Streptococcus pneumoniae (6%, and Staphylococcus aureus (6%. No multidrug resistance was observed, and Pseudomonas aeruginosa occurred in <5% of samples. Patients without microbiological airway colonization showed more severe airflow limitation, hyperinflation, and chronic hypercapnia compared

  16. Postoperative radiotherapy for glioma: improved delineation of the clinical target volume using the geodesic distance calculation.

    Directory of Open Access Journals (Sweden)

    DanFang Yan

    Full Text Available OBJECTS: To introduce a new method for generating the clinical target volume (CTV from gross tumor volume (GTV using the geodesic distance calculation for glioma. METHODS: One glioblastoma patient was enrolled. The GTV and natural barriers were contoured on each slice of the computer tomography (CT simulation images. Then, a graphic processing unit based on a parallel Euclidean distance transform was used to generate the CTV considering natural barriers. Three-dimensional (3D visualization technique was applied to show the delineation results. Speed of operation and precision were compared between this new delineation method and the traditional method. RESULTS: In considering spatial barriers, the shortest distance from the point sheltered from these barriers equals the sum of the distance along the shortest path between the two points; this consists of several segments and evades the spatial barriers, rather than being the direct Euclidean distance between two points. The CTV was generated irregularly rather than as a spherical shape. The time required to generate the CTV was greatly reduced. Moreover, this new method improved inter- and intra-observer variability in defining the CTV. CONCLUSIONS: Compared with the traditional CTV delineation, this new method using geodesic distance calculation not only greatly shortens the time to modify the CTV, but also has better reproducibility.

  17. Dosimetric comparison of lung stereotactic body radiotherapy treatment plans using averaged computed tomography and end-exhalation computed tomography images: Evaluation of the effect of different dose-calculation algorithms and prescription methods

    Energy Technology Data Exchange (ETDEWEB)

    Mitsuyoshi, Takamasa; Nakamura, Mitsuhiro, E-mail: m_nkmr@kuhp.kyoto-u.ac.jp; Matsuo, Yukinori; Ueki, Nami; Nakamura, Akira; Iizuka, Yusuke; Mampuya, Wambaka Ange; Mizowaki, Takashi; Hiraoka, Masahiro

    2016-01-01

    The purpose of this article is to quantitatively evaluate differences in dose distributions calculated using various computed tomography (CT) datasets, dose-calculation algorithms, and prescription methods in stereotactic body radiotherapy (SBRT) for patients with early-stage lung cancer. Data on 29 patients with early-stage lung cancer treated with SBRT were retrospectively analyzed. Averaged CT (Ave-CT) and expiratory CT (Ex-CT) images were reconstructed for each patient using 4-dimensional CT data. Dose distributions were initially calculated using the Ave-CT images and recalculated (in the same monitor units [MUs]) by employing Ex-CT images with the same beam arrangements. The dose-volume parameters, including D{sub 95}, D{sub 90}, D{sub 50}, and D{sub 2} of the planning target volume (PTV), were compared between the 2 image sets. To explore the influence of dose-calculation algorithms and prescription methods on the differences in dose distributions evident between Ave-CT and Ex-CT images, we calculated dose distributions using the following 3 different algorithms: x-ray Voxel Monte Carlo (XVMC), Acuros XB (AXB), and the anisotropic analytical algorithm (AAA). We also used 2 different dose-prescription methods; the isocenter prescription and the PTV periphery prescription methods. All differences in PTV dose-volume parameters calculated using Ave-CT and Ex-CT data were within 3 percentage points (%pts) employing the isocenter prescription method, and within 1.5%pts using the PTV periphery prescription method, irrespective of which of the 3 algorithms (XVMC, AXB, and AAA) was employed. The frequencies of dose-volume parameters differing by >1%pt when the XVMC and AXB were used were greater than those associated with the use of the AAA, regardless of the dose-prescription method employed. All differences in PTV dose-volume parameters calculated using Ave-CT and Ex-CT data on patients who underwent lung SBRT were within 3%pts, regardless of the dose-calculation

  18. Dosimetric comparison of lung stereotactic body radiotherapy treatment plans using averaged computed tomography and end-exhalation computed tomography images: Evaluation of the effect of different dose-calculation algorithms and prescription methods

    International Nuclear Information System (INIS)

    Mitsuyoshi, Takamasa; Nakamura, Mitsuhiro; Matsuo, Yukinori; Ueki, Nami; Nakamura, Akira; Iizuka, Yusuke; Mampuya, Wambaka Ange; Mizowaki, Takashi; Hiraoka, Masahiro

    2016-01-01

    The purpose of this article is to quantitatively evaluate differences in dose distributions calculated using various computed tomography (CT) datasets, dose-calculation algorithms, and prescription methods in stereotactic body radiotherapy (SBRT) for patients with early-stage lung cancer. Data on 29 patients with early-stage lung cancer treated with SBRT were retrospectively analyzed. Averaged CT (Ave-CT) and expiratory CT (Ex-CT) images were reconstructed for each patient using 4-dimensional CT data. Dose distributions were initially calculated using the Ave-CT images and recalculated (in the same monitor units [MUs]) by employing Ex-CT images with the same beam arrangements. The dose-volume parameters, including D 95 , D 90 , D 50 , and D 2 of the planning target volume (PTV), were compared between the 2 image sets. To explore the influence of dose-calculation algorithms and prescription methods on the differences in dose distributions evident between Ave-CT and Ex-CT images, we calculated dose distributions using the following 3 different algorithms: x-ray Voxel Monte Carlo (XVMC), Acuros XB (AXB), and the anisotropic analytical algorithm (AAA). We also used 2 different dose-prescription methods; the isocenter prescription and the PTV periphery prescription methods. All differences in PTV dose-volume parameters calculated using Ave-CT and Ex-CT data were within 3 percentage points (%pts) employing the isocenter prescription method, and within 1.5%pts using the PTV periphery prescription method, irrespective of which of the 3 algorithms (XVMC, AXB, and AAA) was employed. The frequencies of dose-volume parameters differing by >1%pt when the XVMC and AXB were used were greater than those associated with the use of the AAA, regardless of the dose-prescription method employed. All differences in PTV dose-volume parameters calculated using Ave-CT and Ex-CT data on patients who underwent lung SBRT were within 3%pts, regardless of the dose-calculation algorithm or the

  19. Calculation of spatial distribution of absorbed energy in human lung by Monte Carlo method

    International Nuclear Information System (INIS)

    Stefanovic, B.; Ciraj, O.; Ilic, R.; Stankovic, S.

    1999-01-01

    A good performed assessment of the irradiation for any exposed group serves as the base for the radiation protection measures (emergency radiation preparedness, radiation protection optimisation etc.). In this paper results of the numerical experiment for radiation transmission in man lungs, during LAT projection exposure is carried out. The difference between result of numerical experiment in reference to values given in other papers is maximum 12%. (author)

  20. Uranium Mill Tailings Remedial Action Project (UMTRAP), Slick Rock, Colorado, Revision 1. Volume 1, Calculations, Final design for construction

    International Nuclear Information System (INIS)

    1995-09-01

    Volume one contains calculations for: embankment design--embankment material properties; Union Carbide site--bedrock contours; vicinity properties--origin of contamination; North Continent and Union Carbide sites contaminated materials--excavation quantities; and demolition debris--quantity estimate

  1. Volume Transport Stream Function Calculated from World Ocean Atlas 2013 (WOA13-VTSF) and Climatological Wind (NCEI Accession 0138646)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The dataset consists of calculated annual and monthly mean ocean volume transport stream function on 1 degree resolution using the WOA13 (T, S) and corresponding...

  2. Feasibility of repetitive lung function measurements by raised volume rapid thoracoabdominal compression during methacholine challenge in young infants

    DEFF Research Database (Denmark)

    Loland, L.; Bisgaard, H.

    2008-01-01

    BACKGROUND: The aim of the study was to evaluate the feasibility of lung function measurements by the raised volume rapid thoracoabdominal compression (RVRTC) technique during bronchial methacholine challenge in young infants. METHOD: Four hundred two healthy infants were tested at 1 month of age....... The mean acceptability rating among parents was 8 on a scale from 1 to 10, with 13% rating test, with the actual lung function testing accounting for half the time. CONCLUSION: This very comprehensive experience with standardized measurements of lung...... was successfully measured in 87% by transcutaneous oxygen pressure. No serious adverse events were observed during testing or after discharge from the clinic. The methacholine dose range was appropriate as PD could be determined in the majority of infants. FEV(0.5) values in 21% of infants dropped > 40% during...

  3. Assessment of interpatient heterogeneity in tumor radiosensitivity for nonsmall cell lung cancer using tumor-volume variation data

    Energy Technology Data Exchange (ETDEWEB)

    Chvetsov, Alexei V., E-mail: chvetsov2@gmail.com; Schwartz, Jeffrey L.; Mayr, Nina [Department of Radiation Oncology, University of Washington, 1959 NE Pacific Street, Seattle, Washington 98195-6043 (United States); Yartsev, Slav [London Regional Cancer Program, London Health Sciences Centre, 790 Commissioners Road East, London, Ontario 46A 4L6 (Canada)

    2014-06-15

    Purpose: In our previous work, the authors showed that a distribution of cell surviving fractionsS{sub 2} in a heterogeneous group of patients could be derived from tumor-volume variation curves during radiotherapy for head and neck cancer. In this research study, the authors show that this algorithm can be applied to other tumors, specifically in nonsmall cell lung cancer. This new application includes larger patient volumes and includes comparison of data sets obtained at independent institutions. Methods: Our analysis was based on two data sets of tumor-volume variation curves for heterogeneous groups of 17 patients treated for nonsmall cell lung cancer with conventional dose fractionation. The data sets were obtained previously at two independent institutions by using megavoltage computed tomography. Statistical distributions of cell surviving fractionsS{sub 2} and clearance half-lives of lethally damaged cells T{sub 1/2} have been reconstructed in each patient group by using a version of the two-level cell population model of tumor response and a simulated annealing algorithm. The reconstructed statistical distributions of the cell surviving fractions have been compared to the distributions measured using predictive assays in vitro. Results: Nonsmall cell lung cancer presents certain difficulties for modeling surviving fractions using tumor-volume variation curves because of relatively large fractional hypoxic volume, low gradient of tumor-volume response, and possible uncertainties due to breathing motion. Despite these difficulties, cell surviving fractionsS{sub 2} for nonsmall cell lung cancer derived from tumor-volume variation measured at different institutions have similar probability density functions (PDFs) with mean values of 0.30 and 0.43 and standard deviations of 0.13 and 0.18, respectively. The PDFs for cell surviving fractions S{sub 2} reconstructed from tumor volume variation agree with the PDF measured in vitro. Conclusions: The data obtained

  4. Scintigraphic and MR perfusion imaging in preoperative evaluation for lung volume reduction surgery. Pilot study results

    International Nuclear Information System (INIS)

    Johkoh, Takeshi; Mueller, N.L.; Kavanagh, P.V

    2000-01-01

    To compare MR perfusion imaging with perfusion scintigraphy in the evaluation of patients with pulmonary emphysema being considered for lung volume reduction surgery. Six patients with pulmonary emphysema and two normal individuals were evaluated by MR perfusion imaging, perfusion scintigraphy, and selective bilateral pulmonary angiography. MR images were obtained with an enhanced fast gradient recalled echo with three-dimensional Fourier transformation technique (efgre 3D) (6.3/1.3; flip angle, 30 deg C; field of view, 45-48 cm; matrix, 256 x 160). The presence or absence of perfusion defects in each segment was evaluated by two independent observers. Using angiography as the gold standard, the sensitivity, specificity, and accuracy of MR perfusion imaging in detecting focal perfusion abnormalities were 90%, 87%, and 89%, respectively, while those of perfusion scintigraphy were 71%, 76%, and 71%, respectively. The diagnostic accuracy of MR perfusion imaging was significantly higher than that of scintigraphy (p<0.001, McNemar test). There was good agreement between two observers for MR perfusion imaging (kappa statistic, 0.66) and only moderate agreement for perfusion scintigraphy (kappa statistic, 0.51). MR perfusion imaging is superior to perfusion scintigraphy in the evaluation of pulmonary parenchymal perfusion in patients with pulmonary emphysema. (author)

  5. The safety of dipyridamole in patients undergoing myocardial perfusion scintigraphy prior to lung volume reduction surgery

    International Nuclear Information System (INIS)

    Roman, M.R.; Angelides, S.; Parker, M.K.; Silva, I. da; Freeman, A.P.

    2001-01-01

    Patients with end-stage chronic obstructive pulmonary disease (COPD) undergoing lung volume reduction surgery (LVRS) are at high risk of peri-operative cardiac complications, and myocardial perfusion scintigraphy (MPS) is commonly used for risk stratification. This study prospectively assessed the safety of dipyridamole in these patients and compared the incidence of side-effects (particularly dyspnoea) with that in patients undergoing dipyridamole MPS prior to elective non-cardiothoracic surgery. Fifty patients were enrolled: 25 in the LVRS cohort (13 males, 12 females), with a mean age of 65 years and a mean FEV 1 of 0.79 l, and 25 (with no history of asthma or COPD) in the control cohort (14 males, 11 females), with a mean age of 66 years. Fourteen patients (56%) in each group developed side-effects. Dyspnoea was reported by five patients (20%) in the LVRS and two patients (8%) in the control cohort (P=NS). One patient in each cohort developed severe hypotension and bradycardia. Eight (32%) other patients developed minor side-effects in the LVRS cohort compared with 11 (44%) in the control group. All side-effects responded promptly to intravenous aminophylline. In summary, there was a statistically non-significant increase in the incidence of dyspnoea in patients with end-stage COPD and all side-effects responded to aminophylline. Thus, dipyridamole can be used safely in these patients. (orig.)

  6. Revised Calculated Volumes Of Individual Shield Volcanoes At The Young End Of The Hawaiian Ridge

    Science.gov (United States)

    Robinson, J. E.; Eakins, B. W.

    2003-12-01

    Recent, high-resolution multibeam bathymetry and a digital elevation model of the Hawaiian Islands allow us to recalculate Bargar and Jackson's [1974] volumes of coalesced volcanic edifices (Hawaii, Maui-Nui, Oahu, Kauai, and Niihau) and individual shield volcanoes at the young end of the Hawaiian Ridge, taking into account subsidence of the Pacific plate under the load of the volcanoes as modeled by Watts and ten Brink [1989]. Our volume for the Island of Hawaii (2.48 x105 km3) is twice the previous estimate (1.13 x105 km3), due primarily to crustal subsidence, which had not been accounted for in the earlier work. The volcanoes that make up the Hawaii edifice (Mahukona, Kohala, Mauna Kea, Hualalai, Mauna Loa, Kilauea, and Loihi) are generally considered to have formed within the past million years and our revised volume for Hawaii indicates that either magma-supply rates are greater than previously estimated (0.25 km3/yr as opposed to 0.1 km3/yr) or that Hawaii's volcanoes have erupted over a longer period of time (>1 million years). Our results also indicate that magma supply rates have increased dramatically to build the Hawaiian edifices: the average rate of the past 5 million years (0.096 km3/yr) is substantially greater than the overall average of the Hawaiian Ridge (0.018km3/yr) or Emperor Seamounts (0.012 km3/yr) as calculated by Bargar and Jackson, and that rates within the past million years are greater still (0.25 km3/yr). References: Bargar, K. E., and Jackson, E. D., 1974, Calculated volumes of individual shield volcanoes along the Hawaiian-Emperor Chain, Jour. Research U.S. Geol. Survey, Vol. 2, No. 5, p. 545-550. Watts, A. B., and ten Brink, U. S., 1989, Crustal structure, flexure, and subsidence history of the Hawaiian Islands, Jour. Geophys. Res., Vol. 94, No. B8, p. 10,473-10,500.

  7. A prospective study of whether radiation pneumonitis is influenced by low-dose irradiated lung volume in primary lung cancer with chronic pulmonary disease

    International Nuclear Information System (INIS)

    Niibe, Yuzuru; Hayakawa, Kazushige; Masuda, Noriyuki; Yoshimura, Hirokuni

    2007-01-01

    The current study prospectively investigated the optimal dose-volume condition in cases of lung cancer with chronic pulmonary disease compared to those without chronic pulmonary disease. Cases of primary lung cancer treated with intended curative radiation therapy were registered in the current study. Their fraction size was limited to 2-3 Gy, so-called standard fractionation. They were prescribed a total dose of 60 Gy for non-small cell lung cancer (NSCLC; n=17) and a total dose of 54 Gy for small cell lung cancer (SCLC; n=4). Of the 21 patients enrolled in this study, 4 had chronic pulmonary disease (study arm), and the others had no chronic pulmonary disease (control arm). Seven received chemotherapy. Symptomatic radiation pneumonitis occurred in 5. Of the four patients in the study arm, two (50%) experienced symptomatic radiation pneumonitis; only 3 of the 17 patients in the control arm (17.6%) experienced symptomatic radiation pneumonitis. Furthermore, the median V 20 of patients who experienced symptomatic radiation pneumonitis in the study arm was 14%, which was higher than that of patients with no symptomatic radiation pneumonitis in the study arm, 5.8%. On the other hand, in the control arm, the median V 20 of patients with symptomatic radiation pneumonitis was 14.2%, about the same as that of patients with no symptomatic radiation pneumonitis in the control arm, 15.1%. The current study suggested that, as much as 15% of V 20 , might play an important role in cases of lung cancer with chronic pulmonary disease. (author)

  8. Impact of Different Tidal Volume Levels at Low Mechanical Power on Ventilator-Induced Lung Injury in Rats

    Directory of Open Access Journals (Sweden)

    Lillian Moraes

    2018-04-01

    Full Text Available Tidal volume (VT has been considered the main determinant of ventilator-induced lung injury (VILI. Recently, experimental studies have suggested that mechanical power transferred from the ventilator to the lungs is the promoter of VILI. We hypothesized that, as long as mechanical power is kept below a safe threshold, high VT should not be injurious. The present study aimed to investigate the impact of different VT levels and respiratory rates (RR on lung function, diffuse alveolar damage (DAD, alveolar ultrastructure, and expression of genes related to inflammation [interleukin (IL-6], alveolar stretch (amphiregulin, epithelial [club cell secretory protein (CC16] and endothelial [intercellular adhesion molecule (ICAM-1] cell injury, and extracellular matrix damage [syndecan-1, decorin, and metalloproteinase (MMP-9] in experimental acute respiratory distress syndrome (ARDS under low-power mechanical ventilation. Twenty-eight Wistar rats received Escherichia coli lipopolysaccharide intratracheally. After 24 h, 21 animals were randomly assigned to ventilation (2 h with low mechanical power at three different VT levels (n = 7/group: (1 VT = 6 mL/kg and RR adjusted to normocapnia; (2 VT = 13 mL/kg; and 3 VT = 22 mL/kg. In the second and third groups, RR was adjusted to yield low mechanical power comparable to that of the first group. Mechanical power was calculated as [(ΔP,L2/Est,L/2]× RR (ΔP,L = transpulmonary driving pressure, Est,L = static lung elastance. Seven rats were not mechanically ventilated (NV and were used for molecular biology analysis. Mechanical power was comparable among groups, while VT gradually increased. ΔP,L and mechanical energy were higher in VT = 22 mL/kg than VT = 6 mL/kg and VT = 13 mL/kg (p < 0.001 for both. Accordingly, DAD score increased in VT = 22 mL/kg compared to VT = 6 mL/kg and VT = 13 mL/kg [23(18.5–24.75 vs. 16(12–17.75 and 16(13.25–18, p < 0.05, respectively]. VT = 22 mL/kg was associated with higher

  9. Increased expression of AQP 1 and AQP 5 in rat lungs ventilated with low tidal volume is time dependent.

    Directory of Open Access Journals (Sweden)

    Gustavo Fabregat

    Full Text Available BACKGROUND AND GOALS: Mechanical ventilation (MV can induce or worsen pulmonary oedema. Aquaporins (AQPs facilitate the selective and rapid bi-directional movement of water. Their role in the development and resolution of pulmonary oedema is controversial. Our objectives are to determine if prolonged MV causes lung oedema and changes in the expression of AQP 1 and AQP 5 in rats. METHODS: 25 male Wistar rats were subjected to MV with a tidal volume of 10 ml/kg, during 2 hours (n = 12 and 4 hours (n = 13. Degree of oedema was compared with a group of non-ventilated rats (n = 5. The expression of AQP 1 and AQP 5 were determined by western immunoblotting, measuring the amount of mRNA (previously amplified by RT-PCR and immunohistochemical staining of AQPs 1 and 5 in lung samples from all groups. RESULTS: Lung oedema and alveolar-capillary membrane permeability did not change during MV. AQP-5 steady state levels in the western blot were increased (p<0.01 at 2 h and 4 h of MV. But in AQP-1 expression these differences were not found. However, the amount of mRNA for AQP-1 was increased at 2 h and 4 h of MV; and for AQP 5 at 4 h of MV. These findings were corroborated by representative immunohistochemical lung samples. CONCLUSION: In lungs from rats ventilated with a low tidal volume the expression of AQP 5 increases gradually with MV duration, but does not cause pulmonary oedema or changes in lung permeability. AQPs may have a protective effect against the oedema induced by MV.

  10. Effects of body position and extension of the neck and extremities on lung volume measured via computed tomography in red-eared slider turtles (Trachemys scripta elegans).

    Science.gov (United States)

    Mans, Christoph; Drees, Randi; Sladky, Kurt K; Hatt, Jean-Michel; Kircher, Patrick R

    2013-10-15

    To determine the effects of body position and extension of the neck and extremities on CT measurements of ventilated lung volume in red-eared slider turtles (Trachemys scripta elegans). Prospective crossover-design study. 14 adult red-eared slider turtles. CT was performed on turtles in horizontal ventral recumbent and vertical left lateral recumbent, right lateral recumbent, and caudal recumbent body positions. In sedated turtles, evaluations were performed in horizontal ventral recumbent body position with and without extension of the neck and extremities. Lung volumes were estimated from helical CT images with commercial software. Effects of body position, extremity and neck extension, sedation, body weight, and sex on lung volume were analyzed. Mean ± SD volume of dependent lung tissue was significantly decreased in vertical left lateral (18.97 ± 14.65 mL), right lateral (24.59 ± 19.16 mL), and caudal (9.23 ± 12.13 mL) recumbent positions, compared with the same region for turtles in horizontal ventral recumbency (48.52 ± 20.08 mL, 50.66 ± 18.08 mL, and 31.95 ± 15.69 mL, respectively). Total lung volume did not differ among positions because of compensatory increases in nondependent lung tissue. Extension of the extremities and neck significantly increased total lung volume (127.94 ± 35.53 mL), compared with that in turtles with the head, neck, and extremities withdrawn into the shell (103.24 ± 40.13 mL). Vertical positioning of red-eared sliders significantly affected lung volumes and could potentially affect interpretation of radiographs obtained in these positions. Extension of the extremities and neck resulted in the greatest total lung volume.

  11. Calculators

    Science.gov (United States)

    ... ounces of regular beer, 5 ounces of table wine, or 1.5 ounces of 80-proof distilled spirits. Distilled spirits include vodka, whiskey, gin, rum, and ... is 5% alcohol by volume (alc/vol), table wine is about 12% alc/vol, and straight 80-proof distilled spirits is 40% alc/vol. The percent alcohol by ...

  12. Interfractional changes in tumour volume and position during entire radiotherapy courses for lung cancer with respiratory gating and image guidance

    DEFF Research Database (Denmark)

    Juhler-Nøttrup, Trine; Korreman, Stine Sofia; Pedersen, Anders N

    2008-01-01

    were contoured on each CT scan to evaluate the variations in volumes and position. The lung tumours and the mediastinal tumours were contoured separately. The positional variations were measured as 3D mobility vectors and correlated to matching of the scans using the two different strategies. RESULTS......-87% when matched using bony landmarks and 70-76% when matched using skin tattoos. The overlap of the mediastinal tumours were 60-65% and 41-47%, respectively. CONCLUSIONS: Despite the use of gating the tumours varied considerably, regarding both position and volume. The variations in position were...

  13. Non Machinable Volume Calculation Method for 5-Axis Roughing Based on Faceted Models through Closed Bounded Area Evaluation

    Directory of Open Access Journals (Sweden)

    Kiswanto Gandjar

    2017-01-01

    Full Text Available The increase in the volume of rough machining on the CBV area is one of the indicators of increased efficiencyof machining process. Normally, this area is not subject to the rough machining process, so that the volume of the rest of the material is still big. With the addition of CC point and tool orientation to CBV area on a complex surface, the finishing will be faster because the volume of the excess material on this process will be reduced. This paper presents a method for volume calculation of the parts which do not allow further occurrence of the machining process, particulary for rough machining on a complex object. By comparing the total volume of raw materials and machining area volume, the volume of residual material,on which machining process cannot be done,can be determined. The volume of the total machining area has been taken into account for machiningof the CBV and non CBV areas. By using delaunay triangulation for the triangle which includes the machining and CBV areas. The volume will be calculated using Divergence(Gaussian theorem by focusing on the direction of the normal vector on each triangle. This method can be used as an alternative to selecting tothe rough machining methods which select minimum value of nonmachinable volume so that effectiveness can be achieved in the machining process.

  14. 3D thoracoscopic ultrasound volume measurement validation in an ex vivo and in vivo porcine model of lung tumours

    International Nuclear Information System (INIS)

    Hornblower, V D M; Yu, E; Fenster, A; Battista, J J; Malthaner, R A

    2007-01-01

    The purpose of this study was to validate the accuracy and reliability of volume measurements obtained using three-dimensional (3D) thoracoscopic ultrasound (US) imaging. Artificial 'tumours' were created by injecting a liquid agar mixture into spherical moulds of known volume. Once solidified, the 'tumours' were implanted into the lung tissue in both a porcine lung sample ex vivo and a surgical porcine model in vivo. 3D US images were created by mechanically rotating the thoracoscopic ultrasound probe about its long axis while the transducer was maintained in close contact with the tissue. Volume measurements were made by one observer using the ultrasound images and a manual-radial segmentation technique and these were compared with the known volumes of the agar. In vitro measurements had average accuracy and precision of 4.76% and 1.77%, respectively; in vivo measurements had average accuracy and precision of 8.18% and 1.75%, respectively. The 3D thoracoscopic ultrasound can be used to accurately and reproducibly measure 'tumour' volumes both in vivo and ex vivo

  15. 3D thoracoscopic ultrasound volume measurement validation in an ex vivo and in vivo porcine model of lung tumours

    Energy Technology Data Exchange (ETDEWEB)

    Hornblower, V D M [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada); Yu, E [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada); Fenster, A [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada); Battista, J J [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada); Malthaner, R A [Canadian Surgical Technologies and Advanced Robotics, London, Ontario (Canada)

    2007-01-07

    The purpose of this study was to validate the accuracy and reliability of volume measurements obtained using three-dimensional (3D) thoracoscopic ultrasound (US) imaging. Artificial 'tumours' were created by injecting a liquid agar mixture into spherical moulds of known volume. Once solidified, the 'tumours' were implanted into the lung tissue in both a porcine lung sample ex vivo and a surgical porcine model in vivo. 3D US images were created by mechanically rotating the thoracoscopic ultrasound probe about its long axis while the transducer was maintained in close contact with the tissue. Volume measurements were made by one observer using the ultrasound images and a manual-radial segmentation technique and these were compared with the known volumes of the agar. In vitro measurements had average accuracy and precision of 4.76% and 1.77%, respectively; in vivo measurements had average accuracy and precision of 8.18% and 1.75%, respectively. The 3D thoracoscopic ultrasound can be used to accurately and reproducibly measure 'tumour' volumes both in vivo and ex vivo.

  16. Assessment of bronchodilator response through changes in lung volumes in chronic airflow obstruction

    Directory of Open Access Journals (Sweden)

    J.B. Figueroa-Casas

    2003-10-01

    Full Text Available Although FEV1 improvement is routinely used to define bronchodilator (BD response, it correlates poorly with clinical effects. Changes in lung volumes (LV have shown better correlation with exercise tolerance and might be more sensitive to detect BD effects. We assessed the additional contribution of measuring LV before and after BD to detect acute improvement in lung function not demonstrated by FEV1, and the influence of the response criteria selected on this contribution. We analyzed 98 spirometries and plethismographies performed pre and post BD in patients with airflow obstruction (FEV1/FVC 10% of baseline (D>5 anD>15% were also analyzed. FEV1 identified as responders 32% of patients. Greater proportions were uncovered by slow vital capacity (51%, p5 anD>15%. Mean change and proportions of responders for each LV varied significantly (pSi bien el aumento del VEF1 es habitualmente utilizado para definir respuesta a broncodilatadores (BD, su correlación con efectos clínicos es pobre. Los cambios en volúmenes pulmonares (VP han demostrado mejor correlación con tolerancia al ejercicio y podrían ser más sensibles para detectar efectos de los BD. Nosotros evaluamos la contribución adicional de medir VP antes y después de BD para detectar mejoría funcional aguda no demostrada por cambios del VEF1, y la influencia del criterio de respuesta seleccionado en esta contribución. Se analizaron 98 espirometrías y pletismografías realizadas pre y post BD en pacientes con obstrucción al flujo aéreo (VEF1/CVF 10% del basal (D>5 y 15% fueron también analizados. El VEF1 identificó como respondedores a 32% de los pacientes. Proporciones mayores fueron identificadas por capacidad vital lenta (51%, p5 y 15%. El cambio promedio y las proporciones de respondedores para cada VP variaron significativamente (p<0.05 según que el cambio fuese expresado como porcentaje del basal o del valor predicho. Una proporción considerable de pacientes con obstrucci

  17. Test of Effective Solid Angle code for the efficiency calculation of volume source

    Energy Technology Data Exchange (ETDEWEB)

    Kang, M. Y.; Kim, J. H.; Choi, H. D. [Seoul National Univ., Seoul (Korea, Republic of); Sun, G. M. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    It is hard to determine a full energy (FE) absorption peak efficiency curve for an arbitrary volume source by experiment. That's why the simulation and semi-empirical methods have been preferred so far, and many works have progressed in various ways. Moens et al. determined the concept of effective solid angle by considering an attenuation effect of γ-rays in source, media and detector. This concept is based on a semi-empirical method. An Effective Solid Angle code (ESA code) has been developed for years by the Applied Nuclear Physics Group in Seoul National University. ESA code converts an experimental FE efficiency curve determined by using a standard point source to that for a volume source. To test the performance of ESA Code, we measured the point standard sources and voluminous certified reference material (CRM) sources of γ-ray, and compared with efficiency curves obtained in this study. 200∼1500 KeV energy region is fitted well. NIST X-ray mass attenuation coefficient data is used currently to check for the effect of linear attenuation only. We will use the interaction cross-section data obtained from XCOM code to check the each contributing factor like photoelectric effect, incoherent scattering and coherent scattering in the future. In order to minimize the calculation time and code simplification, optimization of algorithm is needed.

  18. A new approach for calculation of volume confined by ECR surface and its area in ECR ion source

    International Nuclear Information System (INIS)

    Filippov, A.V.

    2007-01-01

    The volume confined by the resonance surface and its area are important parameters of the balance equations model for calculation of ion charge-state distribution (CSD) in the electron-cyclotron resonance (ECR) ion source. A new approach for calculation of these parameters is given. This approach allows one to reduce the number of parameters in the balance equations model

  19. Ventilatory protective strategies during thoracic surgery: effects of alveolar recruitment maneuver and low-tidal volume ventilation on lung density distribution.

    Science.gov (United States)

    Kozian, Alf; Schilling, Thomas; Schütze, Hartmut; Senturk, Mert; Hachenberg, Thomas; Hedenstierna, Göran

    2011-05-01

    The increased tidal volume (V(T)) applied to the ventilated lung during one-lung ventilation (OLV) enhances cyclic alveolar recruitment and mechanical stress. It is unknown whether alveolar recruitment maneuvers (ARMs) and reduced V(T) may influence tidal recruitment and lung density. Therefore, the effects of ARM and OLV with different V(T) on pulmonary gas/tissue distribution are examined. Eight anesthetized piglets were mechanically ventilated (V(T) = 10 ml/kg). A defined ARM was applied to the whole lung (40 cm H(2)O for 10 s). Spiral computed tomographic lung scans were acquired before and after ARM. Thereafter, the lungs were separated with an endobronchial blocker. The pigs were randomized to receive OLV in the dependent lung with a V(T) of either 5 or 10 ml/kg. Computed tomography was repeated during and after OLV. The voxels were categorized by density intervals (i.e., atelectasis, poorly aerated, normally aerated, or overaerated). Tidal recruitment was defined as the addition of gas to collapsed lung regions. The dependent lung contained atelectatic (56 ± 10 ml), poorly aerated (183 ± 10 ml), and normally aerated (187 ± 29 ml) regions before ARM. After ARM, lung volume and aeration increased (426 ± 35 vs. 526 ± 69 ml). Respiratory compliance enhanced, and tidal recruitment decreased (95% vs. 79% of the whole end-expiratory lung volume). OLV with 10 ml/kg further increased aeration (atelectasis, 15 ± 2 ml; poorly aerated, 94 ± 24 ml; normally aerated, 580 ± 98 ml) and tidal recruitment (81% of the dependent lung). OLV with 5 ml/kg did not affect tidal recruitment or lung density distribution. (Data are given as mean ± SD.) The ARM improves aeration and respiratory mechanics. In contrast to OLV with high V(T), OLV with reduced V(T) does not reinforce tidal recruitment, indicating decreased mechanical stress.

  20. Poor man medical pneumoplasty: Bronchoscopic lung volume reduction with hot saline versus dissolved doxycycline as a neoteric remedy of pulmonary emphysema

    Directory of Open Access Journals (Sweden)

    A.M. Abumossalam

    2016-01-01

    Conclusion: Bronchoscopic lung volume reduction by hot saline and dissolved doxycycline comes into sight to be a safe and feasible profile with an acceptable outcome that presents an attractive substitute to COPD patients who are physiologically friable.

  1. Volume-Dependent Expression of In-Field and Out-of-Field Effects in the Proton-Irradiated Rat Lung

    NARCIS (Netherlands)

    Coppes, Robert P.; Muijs, Christina T.; Faber, Hette; Gross, Sascha; Schippers, Jacobus M.; Brandenburg, Sytze; Langendijk, Johannes A.; van Luijk, Peter

    2011-01-01

    Purpose: To investigate whether occurance of early radiation effects in lung tissue depends on local close only. Methods and Materials: Twenty-five percent. 50%, 66%, 88%, or 100% of the rat lung was irradiated using single fractions of 150-MeV protons. For all volumes, in-field and out-of-field

  2. Mechanical ventilation with lower tidal volumes and positive end-expiratory pressure prevents pulmonary inflammation in patients without preexisting lung injury

    NARCIS (Netherlands)

    Wolthuis, Esther K.; Choi, Goda; Dessing, Mark C.; Bresser, Paul; Lutter, Rene; Dzoljic, Misa; van der Poll, Tom; Vroom, Margreeth B.; Hollmann, Markus; Schultz, Marcus J.

    2008-01-01

    Background: Mechanical ventilation with high tidal volumes aggravates lung injury in patients with acute lung injury or acute respiratory distress syndrome. The authors sought to determine the effects of short-term mechanical ventilation on local inflammatory responses in patients without

  3. Calculation of Smith-Purcell radiation from a volume strip grating

    International Nuclear Information System (INIS)

    Kube, G.

    2005-01-01

    Smith-Purcell radiation is generated by a charged particle beam passing close to the surface of a diffraction grating. Experimental investigations show a strong dependency of the emitted radiation intensity on the form of the grating profile. This influence is expressed by the radiation factor which is a measure of the grating efficiency, in close analogy to reflection coefficients of optical grating theories. The radiation factor depends on beam energy and observation geometry. Up to now calculations for radiation factors exist for lamellar, sinusoidal and echelette-type grating profiles. In this paper, calculations of Smith-Purcell radiation factors for volume strip gratings which are separated by vacuum gaps are presented. They are based on the modal expansion method and restricted to perfectly conducting grating surfaces and to electron trajectories perpendicular to the grating grooves. An infinite system of coupled linear algebraic equations for the scattered and the transmitted wave amplitudes is derived by imposing the continuity condition at the open end of the grooves, and by the boundary conditions at the remaining part of the interface. Numerical results are presented and discussed in view of using Smith-Purcell radiation for particle beam diagnostic purposes

  4. Optimal dose and volume for postoperative radiotherapy in brain oligometastases from lung cancer: a retrospective study

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Seung Yeun; Kim, Hye Ryun; Cho, Byoung Chul; Lee, Chang Geol; Suh, Chang Ok [Yonsei Cancer Center, Yonsei University College of Medicine, Seoul (Korea, Republic of); Chang, Jong Hee [Dept. of Neurosurgery, Severance Hospital, Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2017-06-15

    To evaluate intracranial control after surgical resection according to the adjuvant treatment received in order to assess the optimal radiotherapy (RT) dose and volume. Between 2003 and 2015, a total of 53 patients with brain oligometastases from non-small cell lung cancer (NSCLC) underwent metastasectomy. The patients were divided into three groups according to the adjuvant treatment received: whole brain radiotherapy (WBRT) ± boost (WBRT ± boost group, n = 26), local RT/Gamma Knife surgery (local RT group, n = 14), and the observation group (n = 13). The most commonly used dose schedule was WBRT (25 Gy in 10 fractions, equivalent dose in 2 Gy fractions [EQD2] 26.04 Gy) with tumor bed boost (15 Gy in 5 fractions, EQD2 16.25 Gy). The WBRT ± boost group showed the lowest 1-year intracranial recurrence rate of 30.4%, followed by the local RT and observation groups, at 66.7%, and 76.9%, respectively (p = 0.006). In the WBRT ± boost group, there was no significant increase in the 1-year new site recurrence rate of patients receiving a lower dose of WBRT (EQD2) <27 Gy compared to that in patients receiving a higher WBRT dose (p = 0.553). The 1-year initial tumor site recurrence rate was lower in patients receiving tumor bed dose (EQD2) of ≥42.3 Gy compared to those receiving <42.3 Gy, although the difference was not significant (p = 0.347). Adding WBRT after resection of brain oligometastases from NSCLC seems to enhance intracranial control. Furthermore, combining lower-dose WBRT with a tumor bed boost may be an attractive option.

  5. Effects of Dexmedetomidine Infusion on Inflammatory Responses and Injury of Lung Tidal Volume Changes during One-Lung Ventilation in Thoracoscopic Surgery: A Randomized Controlled Trial

    Directory of Open Access Journals (Sweden)

    Chun-Yu Wu

    2018-01-01

    Full Text Available One-lung ventilation in thoracic surgery provokes profound systemic inflammatory responses and injury related to lung tidal volume changes. We hypothesized that the highly selective a2-adrenergic agonist dexmedetomidine attenuates these injurious responses. Sixty patients were randomly assigned to receive dexmedetomidine or saline during thoracoscopic surgery. There is a trend of less postoperative medical complication including that no patients in the dexmedetomidine group developed postoperative medical complications, whereas four patients in the saline group did (0% versus 13.3%, p=0.1124. Plasma inflammatory and injurious biomarkers between the baseline and after resumption of two-lung ventilation were particularly notable. The plasma high-mobility group box 1 level decreased significantly from 51.7 (58.1 to 33.9 (45.0 ng.ml−1 (p<0.05 in the dexmedetomidine group, which was not observed in the saline group. Plasma monocyte chemoattractant protein 1 [151.8 (115.1 to 235.2 (186.9 pg.ml−1, p<0.05] and neutrophil elastase [350.8 (154.5 to 421.9 (106.1 ng.ml−1, p<0.05] increased significantly only in the saline group. In addition, plasma interleukin-6 was higher in the saline group than in the dexmedetomidine group at postoperative day 1 [118.8 (68.8 versus 78.5 (58.8 pg.ml−1, p=0.0271]. We conclude that dexmedetomidine attenuates one-lung ventilation-associated inflammatory and injurious responses by inhibiting alveolar neutrophil recruitment in thoracoscopic surgery.

  6. Low tidal volume and high positive end-expiratory pressure mechanical ventilation results in increased inflammation and ventilator-associated lung injury in normal lungs.

    Science.gov (United States)

    Hong, Caron M; Xu, Da-Zhong; Lu, Qi; Cheng, Yunhui; Pisarenko, Vadim; Doucet, Danielle; Brown, Margaret; Aisner, Seena; Zhang, Chunxiang; Deitch, Edwin A; Delphin, Ellise

    2010-06-01

    Protective mechanical ventilation with low tidal volume (Vt) and low plateau pressure reduces mortality and decreases the length of mechanical ventilation in patients with acute respiratory distress syndrome. Mechanical ventilation that will protect normal lungs during major surgical procedures of long duration may improve postoperative outcomes. We performed an animal study comparing 3 ventilation strategies used in the operating room in normal lungs. We compared the effects on pulmonary mechanics, inflammatory mediators, and lung tissue injury. Female pigs were randomized into 3 groups. Group H-Vt/3 (n = 6) was ventilated with a Vt of 15 mL/kg predicted body weight (PBW)/positive end-expiratory pressure (PEEP) of 3 cm H(2)O, group L-Vt/3 (n = 6) with a Vt of 6 mL/kg PBW/PEEP of 3 cm H(2)O, and group L-Vt/10 (n = 6) with a Vt of 6 mL/kg PBW/PEEP of 10 cm H(2)O, for 8 hours. Hemodynamics, airway mechanics, arterial blood gases, and inflammatory markers were monitored. Bronchoalveolar lavage (BAL) was analyzed for inflammatory markers and protein concentration. The right lower lobe was assayed for mRNA of specific cytokines. The right lower lobe and right upper lobe were evaluated histologically. In contrast to groups H-Vt/3 and L-Vt/3, group L-Vt/10 exhibited a 6-fold increase in inflammatory mediators in BAL (P ventilation with high PEEP resulted in increased production of inflammatory markers. Low PEEP resulted in lower levels of inflammatory markers. High Vt/low PEEP resulted in less histologic lung injury.

  7. Adaptive support ventilation may deliver unwanted respiratory rate-tidal volume combinations in patients with acute lung injury ventilated according to an open lung concept.

    Science.gov (United States)

    Dongelmans, Dave A; Paulus, Frederique; Veelo, Denise P; Binnekade, Jan M; Vroom, Margreeth B; Schultz, Marcus J

    2011-05-01

    With adaptive support ventilation, respiratory rate and tidal volume (V(T)) are a function of the Otis least work of breathing formula. We hypothesized that adaptive support ventilation in an open lung ventilator strategy would deliver higher V(T)s to patients with acute lung injury. Patients with acute lung injury were ventilated according to a local guideline advising the use of lower V(T) (6-8 ml/kg predicted body weight), high concentrations of positive end-expiratory pressure, and recruitment maneuvers. Ventilation parameters were recorded when the ventilator was switched to adaptive support ventilation, and after recruitment maneuvers. If V(T) increased more than 8 ml/kg predicted body weight, airway pressure was limited to correct for the rise of V(T). Ten patients with a mean (±SD) Pao(2)/Fio(2) of 171 ± 86 mmHg were included. After a switch from pressure-controlled ventilation to adaptive support ventilation, respiratory rate declined (from 31 ± 5 to 21 ± 6 breaths/min; difference = 10 breaths/min, 95% CI 3-17 breaths/min, P = 0.008) and V(T) increased (from 6.5 ± 0.8 to 9.0 ± 1.6 ml/kg predicted body weight; difference = 2.5 ml, 95% CI 0.4-4.6 ml/kg predicted body weight, P = 0.02). Pressure limitation corrected for the rise of V(T), but minute ventilation declined, forcing the user to switch back to pressure-controlled ventilation. Adaptive support ventilation, compared with pressure-controlled ventilation in an open lung strategy setting, delivers a lower respiratory rate-higher V(T) combination. Pressure limitation does correct for the rise of V(T), but leads to a decline in minute ventilation.

  8. Lung volumes, pulmonary ventilation, and hypoxia following rapid decompression to 60,000 ft (18,288 m).

    Science.gov (United States)

    Connolly, Desmond M; D'Oyly, Timothy J; McGown, Amanda S; Lee, Vivienne M

    2013-06-01

    Rapid decompressions (RD) to 60,000 ft (18,288 m) were undertaken by six subjects to provide evidence of satisfactory performance of a contemporary, partial pressure assembly life support system for the purposes of flight clearance. A total of 12 3-s RDs were conducted with subjects breathing 56% oxygen (balance nitrogen) at the base (simulated cabin) altitude of 22,500 ft (6858 m), switching to 100% oxygen under 72 mmHg (9.6 kPa) of positive pressure at the final (simulated aircraft) altitude. Respiratory pressures, flows, and gas compositions were monitored continuously throughout. All RDs were completed safely, but one subject experienced significant hypoxia during the minute at final altitude, associated with severe hemoglobin desaturation to a low of 53%. Accurate data on subjects' lung volumes were obtained and individual responses post-RD were reviewed in relation to patterns of pulmonary ventilation. The occurrence of severe hypoxia is explained by hypoventilation in conjunction with unusually large lung volumes (total lung capacity 10.18 L). Subjects' lung volumes and patterns of pulmonary ventilation are critical, but idiosyncratic, determinants of alveolar oxygenation and severity of hypoxia following RD to 60,000 ft (18,288 m). At such extreme altitudes even vaporization of water condensate in the oxygen mask may compromise oxygen delivery. An altitude ceiling of 60,000 ft (18,288 m) is the likely threshold for reliable protection using partial pressure assemblies and aircrew should be instructed to take two deep 'clearing' breaths immediately following RD at such extreme pressure breathing altitudes.

  9. Design of the Endobronchial Valve for Emphysema Palliation Trial (VENT: a non-surgical method of lung volume reduction

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    Noppen Marc

    2007-07-01

    Full Text Available Abstract Background Lung volume reduction surgery is effective at improving lung function, quality of life, and mortality in carefully selected individuals with advanced emphysema. Recently, less invasive bronchoscopic approaches have been designed to utilize these principles while avoiding the associated perioperative risks. The Endobronchial Valve for Emphysema PalliatioN Trial (VENT posits that occlusion of a single pulmonary lobe through bronchoscopically placed Zephyr® endobronchial valves will effect significant improvements in lung function and exercise tolerance with an acceptable risk profile in advanced emphysema. Methods The trial design posted on Clinical trials.gov, on August 10, 2005 proposed an enrollment of 270 subjects. Inclusion criteria included: diagnosis of emphysema with forced expiratory volume in one second (FEV1 100%; residual volume > 150% predicted, and heterogeneous emphysema defined using a quantitative chest computed tomography algorithm. Following standardized pulmonary rehabilitation, patients were randomized 2:1 to receive unilateral lobar placement of endobronchial valves plus optimal medical management or optimal medical management alone. The co-primary endpoint was the mean percent change in FEV1 and six minute walk distance at 180 days. Secondary end-points included mean percent change in St. George's Respiratory Questionnaire score and the mean absolute changes in the maximal work load measured by cycle ergometry, dyspnea (mMRC score, and total oxygen use per day. Per patient response rates in clinically significant improvement/maintenance of FEV1 and six minute walk distance and technical success rates of valve placement were recorded. Apriori response predictors based on quantitative CT and lung physiology were defined. Conclusion If endobronchial valves improve FEV1 and health status with an acceptable safety profile in advanced emphysema, they would offer a novel intervention for this progressive and

  10. Lung Volume Reduction in Chronic Obstructive Pulmonary Disease (COPD AND#8211; An Updated Review of Surgical and Endoscopic Procedures

    Directory of Open Access Journals (Sweden)

    Ramakant Dixit

    2012-08-01

    Full Text Available The conventional medical management of emphysema using bronchodilators and anti-inflammatory agents has a limited benefit in patients having advanced hyperinflation of lungs due to destruction of elastic tissue. The natural course of Chronic Obstructive Pulmonary Disease (COPD has been shown to be altered by only smoking cessation and oxygen therapy so far. The lung volume reduction surgery is viewed as another modality to change the natural history of emphysema in recent years. For patients with more generalized emphysema, resection of lung parenchyma improves elastic recoil and chest wall mechanics. An extensive literature search has demonstrated that carefully selected patients of emphysema (i.e. upper lobe predominant disease, low exercise capacity and Forced Expiratory Volume in First Second (FEV1 and DLco and #8804; 20% of predicted receive benefits in terms of symptomatic improvement and physiologic response following Lung Volume Reduction Surgery (LVRS. The resurgent interest in LVRS and National Emphysema Treatment Trial findings for emphysema have stimulated a range of innovative methods, to improve the outcome and reduce complications associated with current LVRS techniques. These novel approaches include surgical resection with compression/banding devices, endobronchial blockers, sealants, obstructing devices and valves and endobronchial bronchial bypass approaches. Experimental data and preliminary results are becoming available for some of these approaches. Most of the published studies so far have been uncontrolled and unblinded. Overall, extensive research in the near future will help to determine the potential clinical applicability of these new approaches to the treatment of emphysema symptoms. [Arch Clin Exp Surg 2012; 1(4.000: 249-257

  11. Regional pressure volume curves by electrical impedance tomography in a model of acute lung injury

    NARCIS (Netherlands)

    Kunst, P. W.; Böhm, S. H.; Vazquez de Anda, G.; Amato, M. B.; Lachmann, B.; Postmus, P. E.; de Vries, P. M.

    2000-01-01

    OBJECTIVE: A new noninvasive method, electrical impedance tomography (EIT), was used to make pressure-impedance (PI) curves in a lung lavage model of acute lung injury in pigs. The lower inflection point (LIP) and the upper deflection point (UDP) were determined from these curves and from the

  12. Comparison of dose calculation algorithms in phantoms with lung equivalent heterogeneities under conditions of lateral electronic disequilibrium

    International Nuclear Information System (INIS)

    Carrasco, P.; Jornet, N.; Duch, M.A.; Weber, L.; Ginjaume, M.; Eudaldo, T.; Jurado, D.; Ruiz, A.; Ribas, M.

    2004-01-01

    An extensive set of benchmark measurement of PDDs and beam profiles was performed in a heterogeneous layer phantom, including a lung equivalent heterogeneity, by means of several detectors and compared against the predicted dose values by different calculation algorithms in two treatment planning systems. PDDs were measured with TLDs, plane parallel and cylindrical ionization chambers and beam profiles with films. Additionally, Monte Carlo simulations by meansof the PENELOPE code were performed. Four different field sizes (10x10, 5x5, 2x2, and1x1 cm 2 ) and two lung equivalent materials (CIRS, ρ e w =0.195 and St. Bartholomew Hospital, London, ρ e w =0.244-0.322) were studied. The performance of four correction-based algorithms and one based on convolution-superposition was analyzed. The correction-based algorithms were the Batho, the Modified Batho, and the Equivalent TAR implemented in the Cadplan (Varian) treatment planning system and the TMS Pencil Beam from the Helax-TMS (Nucletron) treatment planning system. The convolution-superposition algorithm was the Collapsed Cone implemented in the Helax-TMS. The only studied calculation methods that correlated successfully with the measured values with a 2% average inside all media were the Collapsed Cone and the Monte Carlo simulation. The biggest difference between the predicted and the delivered dose in the beam axis was found for the EqTAR algorithm inside the CIRS lung equivalent material in a 2x2 cm 2 18 MV x-ray beam. In these conditions, average and maximum difference against the TLD measurements were 32% and 39%, respectively. In the water equivalent part of the phantom every algorithm correctly predicted the dose (within 2%) everywhere except very close to the interfaces where differences up to 24% were found for 2x2 cm 2 18 MV photon beams. Consistent values were found between the reference detector (ionization chamber in water and TLD in lung) and Monte Carlo simulations, yielding minimal differences (0

  13. Right ventricular function during one-lung ventilation: effects of pressure-controlled and volume-controlled ventilation.

    Science.gov (United States)

    Al Shehri, Abdullah M; El-Tahan, Mohamed R; Al Metwally, Roshdi; Qutub, Hatem; El Ghoneimy, Yasser F; Regal, Mohamed A; Zien, Haytham

    2014-08-01

    To test the effects of pressure-controlled (PCV) and volume-controlled (VCV) ventilation during one-lung ventilation (OLV) for thoracic surgery on right ventricular (RV) function. A prospective, randomized, double-blind, controlled, crossover study. A single university hospital. Fourteen pairs of consecutive patients scheduled for elective thoracotomy. Patients were assigned randomly to ventilate the dependent lung with PCV or VCV mode, each in a randomized crossover order using tidal volume of 6 mL/kg, I: E ratio 1: 2.5, positive end-expiratory pressure (PEEP) of 5 cm H2O and respiratory rate adjusted to maintain normocapnia. Intraoperative changes in RV function (systolic and early diastolic tricuspid annular velocity (TAV), end-systolic volume (ESV), end-diastolic volume (EDV) and fractional area changes (FAC)), airway pressures, compliance and oxygenation index were recorded. The use of PCV during OLV resulted in faster systolic (10.1±2.39 vs. 5.8±1.67 cm/s, respectively), diastolic TAV (9.2±1.99 vs. 4.6±1.42 cm/s, respectively) (prights reserved.

  14. Volumes, capacidades pulmonares e força muscular respiratória no pós-operatório de gastroplastia Lung volumes, lung capacities and respiratory muscle strength following gastroplasty

    Directory of Open Access Journals (Sweden)

    Denise de Moraes Paisani

    2005-04-01

    Full Text Available INTRODUÇÃO: A gastroplastia tem sido cada vez mais indicada no tratamento de obesos mórbidos, pacientes nos quais podemos identificar alteração pronunciada de volumes e capacidades pulmonares. OBJETIVO: Avaliar o comportamento dos volumes e capacidades pulmonares, força muscular respiratória, padrão respiratório e as possíveis complicações pulmonares pós-operatórias. MÉTODO: Vinte e um pacientes (três homens com média de idade de 39 ± 9,7 anos, média de índice de massa corpórea de 50,4 Kg/m², candidatos à gastroplastia, foram avaliados no pré-operatório, primeiro, terceiro e quinto dias de pós-operatório e submetidos a mensuração de volume corrente, capacidade vital, volume minuto, pressões máximas expiratória e inspiratória, e circunferências abdominal e torácica. Observou-se a ocorrência de complicações pulmonares pós-operatórias e mortalidade. RESULTADOS: No primeiro e terceiro dias de pós-operatório houve queda de 47% e 30,5% na capacidade vital, 18% e 12,5% no volume minuto, 28% e 21% no volume corrente, 47% e 32% no índice diafragmático, 51% e 26% na pressão inspiratória máxima, e 39,5% e 26% na pressão expiratória máxima, respectivamente (p BACKGROUND: Gastroplasty has been increasingly used in the treatment of morbidly obese patients, who typically present pronounced alterations in lung volume and capacity. OBJECTIVE: To evaluate post-gastroplasty lung volume, lung capacity, respiratory muscle strength and respiratory pattern, as well as any postoperative pulmonary complications. METHOD: 21 patients (3 of them men, with an average age of 39 ± 9.7 years and an average body mass index of 50.4 kg/m², all candidates for gastroplasty, were evaluated during the preoperative period and again on the first, third and fifth postoperative days. Tidal volume, vital capacity, minute volume, maximal expiratory pressure and maximal inspiratory pressure, as well as chest and waist circumferences, were

  15. SU-F-T-560: Measurement of Dose Blurring Effect Due to Respiratory Motion for Lung Stereotactic Body Radiation Therapy (SBRT) Using Monte Carlo Based Calculation Algorithm

    International Nuclear Information System (INIS)

    Badkul, R; Pokhrel, D; Jiang, H; Lominska, C; Wang, F; Ramanjappa, T

    2016-01-01

    Purpose: Intra-fractional tumor motion due to respiration may potentially compromise dose delivery for SBRT of lung tumors. Even sufficient margins are used to ensure there is no geometric miss of target volume, there is potential dose blurring effect may present due to motion and could impact the tumor coverage if motions are larger. In this study we investigated dose blurring effect of open fields as well as Lung SBRT patients planned using 2 non-coplanar dynamic conformal arcs(NCDCA) and few conformal beams(CB) calculated with Monte Carlo (MC) based algorithm utilizing phantom with 2D-diode array(MapCheck) and ion-chamber. Methods: SBRT lung patients were planned on Brainlab-iPlan system using 4D-CT scan and ITV were contoured on MIP image set and verified on all breathing phase image sets to account for breathing motion and then 5mm margin was applied to generate PTV. Plans were created using two NCDCA and 4-5 CB 6MV photon calculated using XVMC MC-algorithm. 3 SBRT patients plans were transferred to phantom with MapCheck and 0.125cc ion-chamber inserted in the middle of phantom to calculate dose. Also open field 3×3, 5×5 and 10×10 were calculated on this phantom. Phantom was placed on motion platform with varying motion from 5, 10, 20 and 30 mm with duty cycle of 4 second. Measurements were carried out for open fields as well 3 patients plans at static and various degree of motions. MapCheck planar dose and ion-chamber reading were collected and compared with static measurements and computed values to evaluate the dosimetric effect on tumor coverage due to motion. Results: To eliminate complexity of patients plan 3 simple open fields were also measured to see the dose blurring effect with the introduction of motion. All motion measured ionchamber values were normalized to corresponding static value. For open fields 5×5 and 10×10 normalized central axis ion-chamber values were 1.00 for all motions but for 3×3 they were 1 up to 10mm motion and 0.97 and 0

  16. Volume-controlled histographic analysis of pulmonary parenchyma in normal and diffuse parenchymal lung disease: a pilot study

    International Nuclear Information System (INIS)

    Park, Hyo Yong; Lee, Jongmin; Kim, Jong Seob; Won, Chyl Ho; Kang, Duk Sik; Kim, Myoung Nam

    2000-01-01

    To evaluate the clinical usefulness of a home-made histographic analysis system using a lung volume controller. Our study involved ten healthy volunteers, ten emphysema patients, and two idiopathic pulmonary fibrosis (IPF) patients. Using a home-made lung volume controller, images were obtained in the upper, middle, and lower lung zones at 70%, 50%, and 20% of vital capacity. Electron beam tomography was used and scanning parameters were single slice mode, 10-mm slice thickness, 0.4-second scan time, and 35-cm field of view. Usinga home-made semi-automated program, pulmonary parenchyma was isolated and a histogrm then obtained. Seven histographic parameters, namely mean density (MD), density at maximal frequency (DMF), maximal ascending gradient (MAG),maximal ascending gradient density (MAGD), maximal sescending gradient (MDG), maximal descending gradient density (MDGD), and full width at half maximum (FWHM) were derived from the histogram. We compared normal controls with abnormal groups including emphysema and IPF patients at the same respiration levels. A normal histographic zone with ± 1 standard deviation was obtained. Histographic curves of normal controls shifted toward the high density level, and the width of the normal zone increased as the level of inspiration decreased. In ten normal controls, MD, DMF, MAG, MAGD, MDG, MDGD, and FWHM readings at a 70% inspiration level were lower than those at 20% (p less than0.05). At the same level of inspiration, histograms of emphysema patients were locatedat a lower density area than those of normal controls. As inspiration status decreased, histograms of emphysema patients showed diminished shift compared with those of normal controls. At 50% and 20% inspiration levels, the MD, DMF, and MAGD readings of emphysema patients were significantly lower than those of normal controls (p less than 0.05). Compared with those of normal controls, histogrms of the two IPF patients obtained at three inspiration levels were

  17. Impact of PET - CT motion correction in minimising the gross tumour volume in non-small cell lung cancer

    Directory of Open Access Journals (Sweden)

    Michael Masoomi

    2013-10-01

    Full Text Available AbstractObjective: To investigate the impact of respiratory motion on localization, and quantification lung lesions for the Gross Tumour Volume utilizing an in-house developed Auto3Dreg programme and dynamic NURBS-based cardiac-torso digitised phantom (NCAT. Methods: Respiratory motion may result in more than 30% underestimation of the SUV values of lung, liver and kidney tumour lesions. The motion correction technique adopted in this study was an image-based motion correction approach using, an in-house developed voxel-intensity-based and a multi-resolution multi-optimisation (MRMO algorithm. All the generated frames were co-registered to a reference frame using a time efficient scheme. The NCAT phantom was used to generate CT attenuation maps and activity distribution volumes for the lung regions. Quantitative assessment including Region of Interest (ROI, image fidelity and image correlation techniques, as well as semi-quantitative line profile analysis and qualitatively overlaying non-motion and motion corrected image frames were performed. Results: the largest transformation was observed in the Z-direction. The greatest translation was for the frame 3, end inspiration, and the smallest for the frame 5 which was closet frame to the reference frame at 67% expiration. Visual assessment of the lesion sizes, 20-60mm at 3 different locations, apex, mid and base of lung showed noticeable improvement for all the foci and their locations. The maximum improvements for the image fidelity were from 0.395 to 0.930 within the lesion volume of interest. The greatest improvement in activity concentration underestimation, post motion correction, was 7% below the true activity for the 20 mm lesion. The discrepancies in activity underestimation were reduced with increasing the lesion sizes. Overlay activity distribution on the attenuation map showed improved localization of the PET metabolic information to the anatomical CT images. Conclusion: The respiratory

  18. Volume-controlled histographic analysis of pulmonary parenchyma in normal and diffuse parenchymal lung disease: a pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Park, Hyo Yong; Lee, Jongmin; Kim, Jong Seob; Won, Chyl Ho; Kang, Duk Sik [School of Medicine, Kyungpook National University, Taegu (Korea, Republic of); Kim, Myoung Nam [The University of Iowa (United States)

    2000-06-01

    To evaluate the clinical usefulness of a home-made histographic analysis system using a lung volume controller. Our study involved ten healthy volunteers, ten emphysema patients, and two idiopathic pulmonary fibrosis (IPF) patients. Using a home-made lung volume controller, images were obtained in the upper, middle, and lower lung zones at 70%, 50%, and 20% of vital capacity. Electron beam tomography was used and scanning parameters were single slice mode, 10-mm slice thickness, 0.4-second scan time, and 35-cm field of view. Usinga home-made semi-automated program, pulmonary parenchyma was isolated and a histogrm then obtained. Seven histographic parameters, namely mean density (MD), density at maximal frequency (DMF), maximal ascending gradient (MAG),maximal ascending gradient density (MAGD), maximal sescending gradient (MDG), maximal descending gradient density (MDGD), and full width at half maximum (FWHM) were derived from the histogram. We compared normal controls with abnormal groups including emphysema and IPF patients at the same respiration levels. A normal histographic zone with {+-} 1 standard deviation was obtained. Histographic curves of normal controls shifted toward the high density level, and the width of the normal zone increased as the level of inspiration decreased. In ten normal controls, MD, DMF, MAG, MAGD, MDG, MDGD, and FWHM readings at a 70% inspiration level were lower than those at 20% (p less than0.05). At the same level of inspiration, histograms of emphysema patients were locatedat a lower density area than those of normal controls. As inspiration status decreased, histograms of emphysema patients showed diminished shift compared with those of normal controls. At 50% and 20% inspiration levels, the MD, DMF, and MAGD readings of emphysema patients were significantly lower than those of normal controls (p less than 0.05). Compared with those of normal controls, histogrms of the two IPF patients obtained at three inspiration levels were

  19. Factors affecting the lung perfused blood volume in patients with intrapulmonary clots after anti-coagulation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Okada, Munemasa, E-mail: radokada@yamaguchi-u.ac.jp [Department of Radiology, Yamaguchi University Graduate School of Medicine 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Masuda, Yu [4th Grade of 6-year Medicine Doctor Program, Department of Medicine, Yamaguchi University Faculty of Medicine and Health Sciences 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Nakashima, Yoshiteru [Department of Radiology, Yamaguchi Grand Medical Center, Oosaki 77, Hofu, Yamaguchi 747-8511 (Japan); Nomura, Takafumi; Nakao, Sei [Department of Radiology, Yamaguchi University Graduate School of Medicine 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan); Suga, Kazuyoshi [Department of Radiology, St Hills Hospital, Imamurakita 3-7-18, Ube, Yamaguchi 755-0155 (Japan); Kido, Shoji [Computer-aided Diagnosis and Biomedical Imaging Research Biomedical Engineering, Applied Medical Engineering Science Graduate School of Medicine, Yamaguchi University, Tokiwadai 2-16-1, Ube, Yamaguchi 755-8611 (Japan); Matsunaga, Naofumi [Department of Radiology, Yamaguchi University Graduate School of Medicine 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505 (Japan)

    2015-08-15

    Highlights: • Dual-energy CT can provide morphological and functional lung images in the same examination. • The subsequent dual-energy CT demonstrates the increased whole lung perfused blood volume (V{sub 120}) despite the residual intrapulmonary clots after treatment in one examination. • The increased whole lung perfusion (V{sub 120}) and a decreased low perfusion volume (V{sub 5}) result in the improvement in the low perfusion rate (%V{sub 5}) in the patients with acute pulmonary embolism after treatment. - Abstract: Objectives: Factors affecting the improvement in the lung perfused blood volume (LPBV) were evaluated based on the presence of intrapulmonary clots (IPCs) after anti-coagulation therapy using 64-slice dual-energy CT. Materials and methods: 96 patients exhibiting venous thromboembolism underwent initial and repeated LPBV examinations between December 2008 and July 2014. Fifteen patients were excluded due to pulmonary comorbidities, and a total of 81 patients were included in this study. Acute pulmonary embolism (PE) was diagnosed in 46 of the patients (56.7%). LPBV images were three-dimensionally reconstructed with two threshold ranges: 1–120 HU (V{sub 120}) and 1–5 HU (V{sub 5}), and the relative value of V{sub 5} per V{sub 120} expressed as %V{sub 5}. These values were subsequently compared with indicators of the severity of PE, such as the D-dimer level, heart rate and CT measurements. This study was approved by the local ethics committee. Results: In patients with IPCs, the D-dimer, V{sub 5} and %V{sub 5}values were significantly larger (p ≤ 0.01) in the initial LPBV, although these differences disappeared in subsequent LPBV after treatment. The right ventricular (RV) diameter, RV/left ventricular (RV/LV) diameter ratio and %V{sub 5} values were also significantly reduced, whereas the V{sub 5} value did not significantly decrease (p = 0.07), but V{sub 120} value significantly increased (p < 0.001) after treatment. However, in

  20. Mechanical ventilation with lower tidal volumes and positive end-expiratory pressure prevents pulmonary inflammation in patients without preexisting lung injury.

    Science.gov (United States)

    Wolthuis, Esther K; Choi, Goda; Dessing, Mark C; Bresser, Paul; Lutter, Rene; Dzoljic, Misa; van der Poll, Tom; Vroom, Margreeth B; Hollmann, Markus; Schultz, Marcus J

    2008-01-01

    Mechanical ventilation with high tidal volumes aggravates lung injury in patients with acute lung injury or acute respiratory distress syndrome. The authors sought to determine the effects of short-term mechanical ventilation on local inflammatory responses in patients without preexisting lung injury. Patients scheduled to undergo an elective surgical procedure (lasting > or = 5 h) were randomly assigned to mechanical ventilation with either higher tidal volumes of 12 ml/kg ideal body weight and no positive end-expiratory pressure (PEEP) or lower tidal volumes of 6 ml/kg and 10 cm H2O PEEP. After induction of anesthesia and 5 h thereafter, bronchoalveolar lavage fluid and/or blood was investigated for polymorphonuclear cell influx, changes in levels of inflammatory markers, and nucleosomes. Mechanical ventilation with lower tidal volumes and PEEP (n = 21) attenuated the increase of pulmonary levels of interleukin (IL)-8, myeloperoxidase, and elastase as seen with higher tidal volumes and no PEEP (n = 19). Only for myeloperoxidase, a difference was found between the two ventilation strategies after 5 h of mechanical ventilation (P volumes and PEEP may limit pulmonary inflammation in mechanically ventilated patients without preexisting lung injury. The specific contribution of both lower tidal volumes and PEEP on the protective effects of the lung should be further investigated.

  1. A proposed framework for consensus-based lung tumour volume auto-segmentation in 4D computed tomography imaging

    Science.gov (United States)

    Martin, Spencer; Brophy, Mark; Palma, David; Louie, Alexander V.; Yu, Edward; Yaremko, Brian; Ahmad, Belal; Barron, John L.; Beauchemin, Steven S.; Rodrigues, George; Gaede, Stewart

    2015-02-01

    This work aims to propose and validate a framework for tumour volume auto-segmentation based on ground-truth estimates derived from multi-physician input contours to expedite 4D-CT based lung tumour volume delineation. 4D-CT datasets of ten non-small cell lung cancer (NSCLC) patients were manually segmented by 6 physicians. Multi-expert ground truth (GT) estimates were constructed using the STAPLE algorithm for the gross tumour volume (GTV) on all respiratory phases. Next, using a deformable model-based method, multi-expert GT on each individual phase of the 4D-CT dataset was propagated to all other phases providing auto-segmented GTVs and motion encompassing internal gross target volumes (IGTVs) based on GT estimates (STAPLE) from each respiratory phase of the 4D-CT dataset. Accuracy assessment of auto-segmentation employed graph cuts for 3D-shape reconstruction and point-set registration-based analysis yielding volumetric and distance-based measures. STAPLE-based auto-segmented GTV accuracy ranged from (81.51  ±  1.92) to (97.27  ±  0.28)% volumetric overlap of the estimated ground truth. IGTV auto-segmentation showed significantly improved accuracies with reduced variance for all patients ranging from 90.87 to 98.57% volumetric overlap of the ground truth volume. Additional metrics supported these observations with statistical significance. Accuracy of auto-segmentation was shown to be largely independent of selection of the initial propagation phase. IGTV construction based on auto-segmented GTVs within the 4D-CT dataset provided accurate and reliable target volumes compared to manual segmentation-based GT estimates. While inter-/intra-observer effects were largely mitigated, the proposed segmentation workflow is more complex than that of current clinical practice and requires further development.

  2. A proposed framework for consensus-based lung tumour volume auto-segmentation in 4D computed tomography imaging

    International Nuclear Information System (INIS)

    Martin, Spencer; Rodrigues, George; Gaede, Stewart; Brophy, Mark; Barron, John L; Beauchemin, Steven S; Palma, David; Louie, Alexander V; Yu, Edward; Yaremko, Brian; Ahmad, Belal

    2015-01-01

    This work aims to propose and validate a framework for tumour volume auto-segmentation based on ground-truth estimates derived from multi-physician input contours to expedite 4D-CT based lung tumour volume delineation. 4D-CT datasets of ten non-small cell lung cancer (NSCLC) patients were manually segmented by 6 physicians. Multi-expert ground truth (GT) estimates were constructed using the STAPLE algorithm for the gross tumour volume (GTV) on all respiratory phases. Next, using a deformable model-based method, multi-expert GT on each individual phase of the 4D-CT dataset was propagated to all other phases providing auto-segmented GTVs and motion encompassing internal gross target volumes (IGTVs) based on GT estimates (STAPLE) from each respiratory phase of the 4D-CT dataset. Accuracy assessment of auto-segmentation employed graph cuts for 3D-shape reconstruction and point-set registration-based analysis yielding volumetric and distance-based measures. STAPLE-based auto-segmented GTV accuracy ranged from (81.51  ±  1.92) to (97.27  ±  0.28)% volumetric overlap of the estimated ground truth. IGTV auto-segmentation showed significantly improved accuracies with reduced variance for all patients ranging from 90.87 to 98.57% volumetric overlap of the ground truth volume. Additional metrics supported these observations with statistical significance. Accuracy of auto-segmentation was shown to be largely independent of selection of the initial propagation phase. IGTV construction based on auto-segmented GTVs within the 4D-CT dataset provided accurate and reliable target volumes compared to manual segmentation-based GT estimates. While inter-/intra-observer effects were largely mitigated, the proposed segmentation workflow is more complex than that of current clinical practice and requires further development. (paper)

  3. Quantification of lung surface area using computed tomography

    Directory of Open Access Journals (Sweden)

    Xing Li

    2010-10-01

    Full Text Available Abstract Objective To refine the CT prediction of emphysema by comparing histology and CT for specific regions of lung. To incorporate both regional lung density measured by CT and cluster analysis of low attenuation areas for comparison with histological measurement of surface area per unit lung volume. Methods The histological surface area per unit lung volume was estimated for 140 samples taken from resected lung specimens of fourteen subjects. The region of the lung sampled for histology was located on the pre-operative CT scan; the regional CT median lung density and emphysematous lesion size were calculated using the X-ray attenuation values and a low attenuation cluster analysis. Linear mixed models were used to examine the relationships between histological surface area per unit lung volume and CT measures. Results The median CT lung density, low attenuation cluster analysis, and the combination of both were important predictors of surface area per unit lung volume measured by histology (p Conclusion Combining CT measures of lung density and emphysematous lesion size provides a more accurate estimate of lung surface area per unit lung volume than either measure alone.

  4. The use of phase sequence image sets to reconstruct the total volume occupied by a mobile lung tumor

    International Nuclear Information System (INIS)

    Gagne, Isabelle M.; Robinson, Don M.; Halperin, Ross; Roa, Wilson

    2005-01-01

    The use of phase sequence image (PSI) sets to reveal the total volume occupied by a mobile target is presented. Isocontrast composite clinical target volumes (CCTVs) may be constructed from PSI sets in order to reveal the total volume occupied by a mobile target during the course of its travel. The ability of the CCTV technique to properly account for target motion is demonstrated by comparison to contours of the true total volume occupied (TVO) for a number of experimental phantom geometries. Finally, using real patient data, the clinical utility of the CCTV technique to properly account for internal tumor motion while minimizing the volume of healthy lung tissue irradiated is assessed by comparison to the standard approach of applying safety margins. Results of the phantom study reveal that CCTV cross sections constructed at the 20% isocontrast level yield good agreement with the total cross sections (TXO) of mobile targets. These CCTVs conform well to the TVOs of the moving targets examined whereby the addition of small uniform margins ensures complete circumscription of the TVO with the inclusion of minimal amounts of surrounding external volumes. The CCTV technique is seen to be clearly superior to the common practice of the addition of safety margins to individual CTV contours in order to account for internal target motion. Margins required with the CCTV technique are eight to ten times smaller than those required with individual CTVs

  5. Very low tidal volume ventilation with associated hypercapnia--effects on lung injury in a model for acute respiratory distress syndrome.

    Directory of Open Access Journals (Sweden)

    Hans Fuchs

    Full Text Available BACKGROUND: Ventilation using low tidal volumes with permission of hypercapnia is recommended to protect the lung in acute respiratory distress syndrome. However, the most lung protective tidal volume in association with hypercapnia is unknown. The aim of this study was to assess the effects of different tidal volumes with associated hypercapnia on lung injury and gas exchange in a model for acute respiratory distress syndrome. METHODOLOGY/PRINCIPAL FINDINGS: In this randomized controlled experiment sixty-four surfactant-depleted rabbits were exposed to 6 hours of mechanical ventilation with the following targets: Group 1: tidal volume = 8-10 ml/kg/PaCO(2 = 40 mm Hg; Group 2: tidal volume = 4-5 ml/kg/PaCO(2 = 80 mm Hg; Group 3: tidal volume = 3-4 ml/kg/PaCO(2 = 120 mm Hg; Group 4: tidal volume = 2-3 ml/kg/PaCO(2 = 160 mm Hg. Decreased wet-dry weight ratios of the lungs, lower histological lung injury scores and higher PaO(2 were found in all low tidal volume/hypercapnia groups (group 2, 3, 4 as compared to the group with conventional tidal volume/normocapnia (group 1. The reduction of the tidal volume below 4-5 ml/kg did not enhance lung protection. However, oxygenation and lung protection were maintained at extremely low tidal volumes in association with very severe hypercapnia and no adverse hemodynamic effects were observed with this strategy. CONCLUSION: Ventilation with low tidal volumes and associated hypercapnia was lung protective. A tidal volume below 4-5 ml/kg/PaCO(2 80 mm Hg with concomitant more severe hypercapnic acidosis did not increase lung protection in this surfactant deficiency model. However, even at extremely low tidal volumes in association with severe hypercapnia lung protection and oxygenation were maintained.

  6. SU-E-J-79: Internal Tumor Volume Motion and Volume Size Assessment Using 4D CT Lung Data

    Energy Technology Data Exchange (ETDEWEB)

    Jurkovic, I [University of Texas Health Science Center at San Antonio, San Antonio, TX (United States); Stathakis, S; Li, Y; Patel, A; Vincent, J; Papanikolaou, N; Mavroidis, P [Cancer Therapy and Research Center University of Texas Health Sciences Center at San Antonio, San Antonio, TX (United States)

    2014-06-01

    Purpose: To assess internal tumor volume change through breathing cycle and associated tumor motion using the 4DCT data. Methods: Respiration induced volume change through breathing cycle and associated motion was analyzed for nine patients that were scanned during the different respiratory phases. The examined datasets were the maximum and average intensity projections (MIP and AIP) and the 10 phases of the respiratory cycle. The internal target volume (ITV) was delineated on each of the phases and the planning target volume (PTV) was then created by adding setup margins to the ITV. Tumor motion through the phases was assessed using the acquired 4DCT dataset, which was then used to determine if the margins used for the ITV creation successfully encompassed the tumor in three dimensions. Results: Results showed that GTV motion along the superior inferior axes was the largest in all the cases independent of the tumor location and/or size or the use of abdomen compression. The extent of the tumor motion was found to be connected with the size of the GTV. The smallest GTVs exhibited largest motion vector independent of the tumor location. The motion vector size varied through the phases depending on the tumor size and location and it was smallest for phases 20 and 30. The smaller the volume of the delineated GTV, the greater its volume difference through the different respiratory phases was. The average GTV volume change was largest for the phases 60 and 70. Conclusion: Even if GTV is delineated using both AIP and MIP datasets, its motion extent will exceed the used margins especially for the very small GTV volumes. When the GTV size is less than 10 cc it is recommended to use fusion of the GTVs through all the phases to create the planning ITV.

  7. Gross tumor volume dependency on phase sorting methods of four-dimensional computed tomography images for lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Soo Yong; Lim, Sang Wook; Ma, Sun Young; Yu, Je Sang [Dept. of Radiation Oncology, Kosin University Gospel Hospital, Kosin University College of Medicine, Busan (Korea, Republic of)

    2017-09-15

    To see the gross tumor volume (GTV) dependency according to the phase selection and reconstruction methods, we measured and analyzed the changes of tumor volume and motion at each phase in 20 cases with lung cancer patients who underwent image-guided radiotherapy. We retrospectively analyzed four-dimensional computed tomography (4D-CT) images in 20 cases of 19 patients who underwent image-guided radiotherapy. The 4D-CT images were reconstructed by the maximum intensity projection (MIP) and the minimum intensity projection (Min-IP) method after sorting phase as 40%–60%, 30%–70%, and 0%–90%. We analyzed the relationship between the range of motion and the change of GTV according to the reconstruction method. The motion ranges of GTVs are statistically significant only for the tumor motion in craniocaudal direction. The discrepancies of GTV volume and motion between MIP and Min-IP increased rapidly as the wider ranges of duty cycles are selected. As narrow as possible duty cycle such as 40%–60% and MIP reconstruction was suitable for lung cancer if the respiration was stable. Selecting the reconstruction methods and duty cycle is important for small size and for large motion range tumors.

  8. Impact of spinal anaesthesia on peri-operative lung volumes in obese and morbidly obese female patients.

    Science.gov (United States)

    Regli, A; von Ungern-Sternberg, B S; Reber, A; Schneider, M C

    2006-03-01

    Although obesity predisposes to postoperative pulmonary complications, data on the relationship between body mass index (BMI) and peri-operative respiratory performance are limited. We prospectively studied the impact of spinal anaesthesia, obesity and vaginal surgery on lung volumes measured by spirometry in 28 patients with BMI 30-40 kg.m(-2) and in 13 patients with BMI > or = 40 kg.m(-2). Vital capacity, forced vital capacity, forced expiratory volume in 1 s, mid-expiratory and peak expiratory flows were measured during the pre-operative visit (baseline), after effective spinal anaesthesia with premedication, and after the operation at 20 min, 1 h, 2 h, and 3 h (after mobilisation). Spinal anaesthesia and premedication were associated with a significant decrease in spirometric parameters. Spinal anaesthesia and premedication were associated with a significant decrease in spirometric parameters; mean (SD) vital capacities were - 19% (6.4) in patients with BMI 30-40 kg.m(-2) and - 33% (9.0) in patients with BMI > 40 kg.m(-2). The decrease of lung volumes remained constant for 2 h, whereas 3 h after the operation and after mobilisation, spirometric parameters significantly improved in all patients. This study showed that both spinal anaesthesia and obesity significantly impaired peri-operative respiratory function.

  9. Automated lung volumetry from routine thoracic CT scans: how reliable is the result?

    Science.gov (United States)

    Haas, Matthias; Hamm, Bernd; Niehues, Stefan M

    2014-05-01

    Today, lung volumes can be easily calculated from chest computed tomography (CT) scans. Modern postprocessing workstations allow automated volume measurement of data sets acquired. However, there are challenges in the use of lung volume as an indicator of pulmonary disease when it is obtained from routine CT. Intra-individual variation and methodologic aspects have to be considered. Our goal was to assess the reliability of volumetric measurements in routine CT lung scans. Forty adult cancer patients whose lungs were unaffected by the disease underwent routine chest CT scans in 3-month intervals, resulting in a total number of 302 chest CT scans. Lung volume was calculated by automatic volumetry software. On average of 7.2 CT scans were successfully evaluable per patient (range 2-15). Intra-individual changes were assessed. In the set of patients investigated, lung volume was approximately normally distributed, with a mean of 5283 cm(3) (standard deviation = 947 cm(3), skewness = -0.34, and curtosis = 0.16). Between different scans in one and the same patient the median intra-individual standard deviation in lung volume was 853 cm(3) (16% of the mean lung volume). Automatic lung segmentation of routine chest CT scans allows a technically stable estimation of lung volume. However, substantial intra-individual variations have to be considered. A median intra-individual deviation of 16% in lung volume between different routine scans was found. Copyright © 2014 AUR. Published by Elsevier Inc. All rights reserved.

  10. Association Between Use of Lung-Protective Ventilation With Lower Tidal Volumes and Clinical Outcomes Among Patients Without Acute Respiratory Distress Syndrome A Meta-analysis

    NARCIS (Netherlands)

    Serpa Neto, Ary; Cardoso, Sérgio Oliveira; Manetta, José Antônio; Pereira, Victor Galvão Moura; Espósito, Daniel Crepaldi; Pasqualucci, Manoela de Oliveira Prado; Damasceno, Maria Cecília Toledo; Schultz, Marcus J.

    2012-01-01

    Context Lung-protective mechanical ventilation with the use of lower tidal volumes has been found to improve outcomes of patients with acute respiratory distress syndrome (ARDS). It has been suggested that use of lower tidal volumes also benefits patients who do not have ARDS. Objective To determine

  11. Analysis of Lung Tumor Motion in a Large Sample: Patterns and Factors Influencing Precise Delineation of Internal Target Volume

    Energy Technology Data Exchange (ETDEWEB)

    Knybel, Lukas [Department of Oncology, University Hospital Ostrava, Ostrava (Czech Republic); VŠB-Technical University of Ostrava, Ostrava (Czech Republic); Cvek, Jakub, E-mail: Jakub.cvek@fno.cz [Department of Oncology, University Hospital Ostrava, Ostrava (Czech Republic); Molenda, Lukas; Stieberova, Natalie; Feltl, David [Department of Oncology, University Hospital Ostrava, Ostrava (Czech Republic)

    2016-11-15

    Purpose/Objective: To evaluate lung tumor motion during respiration and to describe factors affecting the range and variability of motion in patients treated with stereotactic ablative radiation therapy. Methods and Materials: Log file analysis from online respiratory tumor tracking was performed in 145 patients. Geometric tumor location in the lungs, tumor volume and origin (primary or metastatic), sex, and tumor motion amplitudes in the superior-inferior (SI), latero-lateral (LL), and anterior-posterior (AP) directions were recorded. Tumor motion variability during treatment was described using intrafraction/interfraction amplitude variability and tumor motion baseline changes. Tumor movement dependent on the tumor volume, position and origin, and sex were evaluated using statistical regression and correlation analysis. Results: After analysis of >500 hours of data, the highest rates of motion amplitudes, intrafraction/interfraction variation, and tumor baseline changes were in the SI direction (6.0 ± 2.2 mm, 2.2 ± 1.8 mm, 1.1 ± 0.9 mm, and −0.1 ± 2.6 mm). The mean motion amplitudes in the lower/upper geometric halves of the lungs were significantly different (P<.001). Motion amplitudes >15 mm were observed only in the lower geometric quarter of the lungs. Higher tumor motion amplitudes generated higher intrafraction variations (R=.86, P<.001). Interfraction variations and baseline changes >3 mm indicated tumors contacting mediastinal structures or parietal pleura. On univariate analysis, neither sex nor tumor origin (primary vs metastatic) was an independent predictive factor of different movement patterns. Metastatic lesions in women, but not men, showed significantly higher mean amplitudes (P=.03) and variability (primary, 2.7 mm; metastatic, 4.9 mm; P=.002) than primary tumors. Conclusion: Online tracking showed significant irregularities in lung tumor movement during respiration. Motion amplitude was significantly lower in upper lobe

  12. Analysis of Lung Tumor Motion in a Large Sample: Patterns and Factors Influencing Precise Delineation of Internal Target Volume

    International Nuclear Information System (INIS)

    Knybel, Lukas; Cvek, Jakub; Molenda, Lukas; Stieberova, Natalie; Feltl, David

    2016-01-01

    Purpose/Objective: To evaluate lung tumor motion during respiration and to describe factors affecting the range and variability of motion in patients treated with stereotactic ablative radiation therapy. Methods and Materials: Log file analysis from online respiratory tumor tracking was performed in 145 patients. Geometric tumor location in the lungs, tumor volume and origin (primary or metastatic), sex, and tumor motion amplitudes in the superior-inferior (SI), latero-lateral (LL), and anterior-posterior (AP) directions were recorded. Tumor motion variability during treatment was described using intrafraction/interfraction amplitude variability and tumor motion baseline changes. Tumor movement dependent on the tumor volume, position and origin, and sex were evaluated using statistical regression and correlation analysis. Results: After analysis of >500 hours of data, the highest rates of motion amplitudes, intrafraction/interfraction variation, and tumor baseline changes were in the SI direction (6.0 ± 2.2 mm, 2.2 ± 1.8 mm, 1.1 ± 0.9 mm, and −0.1 ± 2.6 mm). The mean motion amplitudes in the lower/upper geometric halves of the lungs were significantly different (P 15 mm were observed only in the lower geometric quarter of the lungs. Higher tumor motion amplitudes generated higher intrafraction variations (R=.86, P 3 mm indicated tumors contacting mediastinal structures or parietal pleura. On univariate analysis, neither sex nor tumor origin (primary vs metastatic) was an independent predictive factor of different movement patterns. Metastatic lesions in women, but not men, showed significantly higher mean amplitudes (P=.03) and variability (primary, 2.7 mm; metastatic, 4.9 mm; P=.002) than primary tumors. Conclusion: Online tracking showed significant irregularities in lung tumor movement during respiration. Motion amplitude was significantly lower in upper lobe tumors; higher interfraction amplitude variability indicated tumors in contact

  13. Interfractional changes in tumour volume and position during entire radiotherapy courses for lung cancer with respiratory gating and image guidance

    Energy Technology Data Exchange (ETDEWEB)

    Juhler-Noettrup, Trine; Korreman, Stine S.; Pedersen, Anders N.; Persson, Gitte F.; Aarup, Lasse R.; Nystroem, Haakan; Olsen, Mikael; Tarnavski, Nikolai; Specht, Lena (Dept. of Radiation Oncology, The Finsen Centre, Copenhagen (Denmark))

    2008-08-15

    Introduction. With the purpose of implementing gated radiotherapy for lung cancer patients, this study investigated the interfraction variations in tumour size and internal displacement over entire treatment courses. To explore the potential of image guided radiotherapy (IGRT) the variations were measured using a set-up strategy based on imaging of bony landmarks and compared to a strategy using in room lasers, skin tattoos and cupper landmarks. Materials and methods. During their six week treatment course of 60Gy in 2Gy fractions, ten patients underwent 3 respiratory gated CT scans. The tumours were contoured on each CT scan to evaluate the variations in volumes and position. The lung tumours and the mediastinal tumours were contoured separately. The positional variations were measured as 3D mobility vectors and correlated to matching of the scans using the two different strategies. Results. The tumour size was significantly reduced from the first to the last CT scan. For the lung tumours the reduction was 19%, p=0.03, and for the mediastinal tumours the reduction was 34%, p=0.0007. The mean 3D mobility vector and the SD for the lung tumours was 0.51cm (+-0.21) for matching using bony landmarks and 0.85cm (+-0.54) for matching using skin tattoos. For the mediastinal tumours the corresponding vectors and SD's were 0.55cm (+-0.19) and 0.72cm (+-0.43). The differences between the vectors were significant for the lung tumours p=0.004. The interfractional overlap of lung tumours was 80-87% when matched using bony landmarks and 70-76% when matched using skin tattoos. The overlap of the mediastinal tumours were 60-65% and 41-47%, respectively. Conclusions. Despite the use of gating the tumours varied considerably, regarding both position and volume. The variations in position were dependent on the set-up strategy. Set-up using IGRT was superior to set-up using skin tattoos.

  14. Interfractional changes in tumour volume and position during entire radiotherapy courses for lung cancer with respiratory gating and image guidance

    International Nuclear Information System (INIS)

    Juhler-Noettrup, Trine; Korreman, Stine S.; Pedersen, Anders N.; Persson, Gi tte F.; Aarup, Lasse R.; Nystroem, Haakan; Olsen, Mikael; Tarnavski, Nikolai; Sp echt, Lena

    2008-01-01

    Introduction. With the purpose of implementing gated radiotherapy for lung cancer patients, this study investigated the interfraction variations in tumour size and internal displacement over entire treatment courses. To explore the potential of image guided radiotherapy (IGRT) the variations were measured using a set-up strategy based on imaging of bony landmarks and compared to a strategy using in room lasers, skin tattoos and cupper landmarks. Materials and methods. During their six week treatment course of 60Gy in 2Gy fractions, ten patients underwent 3 respiratory gated CT scans. The tumours were contoured on each CT scan to evaluate the variations in volumes and position. The lung tumours and the mediastinal tumours were contoured separately. The positional variations were measured as 3D mobility vectors and correlated to matching of the scans using the two different strategies. Results. The tumour size was significantly reduced from the first to the last CT scan. For the lung tumours the reduction was 19%, p=0.03, and for the mediastinal tumours the reduction was 34%, p=0.0007. The mean 3D mobility vector and the SD for the lung tumours was 0.51cm (±0.21) for matching using bony landmarks and 0.85cm (±0.54) for matching using skin tattoos. For the mediastinal tumours the corresponding vectors and SD's were 0.55cm (±0.19) and 0.72cm (±0.43). The differences between the vectors were significant for the lung tumours p=0.004. The interfractional overlap of lung tumours was 80-87% when matched using bony landmarks and 70-76% when matched using skin tattoos. The overlap of the mediastinal tumours were 60-65% and 41-47%, respectively. Conclusions. Despite the use of gating the tumours varied considerably, regarding both position and volume. The variations in position were dependent on the set-up strategy. Set-up using IGRT was superior to set-up using skin tattoos

  15. WE-AB-207B-12: Prospective Study of the Relationship Between Dose-Volume Clinical Toxicity and Patient Reported Outcomes in Lung Cancer Patients Treated with SBRT

    Energy Technology Data Exchange (ETDEWEB)

    Mayyas, E; Vance, S; Brown, S; Liu, J; Kim, J; Zhen, S; Devpura, S; Ajlouni, M; Salim, S; Chetty, I; Movsas, B [Henry Ford Health System, Detroit, MI (United States)

    2016-06-15

    Purpose: To determine in a prospective study, the correlation between radiation dose/volume, clinical toxicities and patient-reported, quality of life (QOL) resulting from lung SBRT. Methods: For 106 non-small cell lung cancer (NSCLC) patients receiving SBRT (12 Gy × 4), symptoms including cough, dyspnea, fatigue and pneumonitis were measured at baseline (before treatment), after treatment and 3, 6, and 12 months post-treatment. Toxicity was graded from zero to five. Dosimetric parameters such as the MLD, D10%, D20%, and lung subvolumes (V10 and V20) were obtained from the treatment plan. Dosimetric parameters and number of patients demonstrating toxicity ≥ grade 2 were tabulated. Linear regression analysis was used to calculate correlations between MLD and D10, D20, V10 and V20. Results: The percentages of patients with > grade 2 pneumonitis, fatigue, cough, and dyspnea over 3 to 12 months increased from 0.0% to 3.5%, 3.2% to 10.5%, 4.3% to 8.3%, and 10.8% to 18.8%, respectively. Computed dose indices D10%, D20% were 7.9±4.8 Gy and 3.0±2.3 Gy, respectively. MLD ranged from 0.34 Gy up to 9.9 Gy with overall average 3.0±1.7 Gy. The averages of the subvolumes V10 and V20 were respectively 8.9±5.3% and 3.0±2.4%. The linear regression analysis showed that V10 and D10 demonstrated the strongest correlation to MLD; R2= 0.92 and 0.87, respectively. V20, and D20 were also strongly correlated with MLD; R2 = 0.81 and 0.84 respectively. A correlation was also found to exist between MLD > 2 Gy and ≥ grade 2 cough and dyspnea. Subvolume values for 2Gy MLD were 5.3% for V10 and 2% for V20. Conclusion: Dosimetric indices: MLD ≥ 2Gy, D10 ≥ 5Gy and V10 ≥ 5% of the total lung volume were predictive of > grade 2 cough and dyspnea QOL data. The QOL results are a novel component of this work. acknowledgement of the Varian grant support.

  16. Large volume unresectable locally advanced non-small cell lung cancer: acute toxicity and initial outcome results with rapid arc

    Directory of Open Access Journals (Sweden)

    Fogliata Antonella

    2010-10-01

    Full Text Available Abstract Background To report acute toxicity, initial outcome results and planning therapeutic parameters in radiation treatment of advanced lung cancer (stage III with volumetric modulated arcs using RapidArc (RA. Methods Twenty-four consecutive patients were treated with RA. All showed locally advanced non-small cell lung cancer with stage IIIA-IIIB and with large volumes (GTV:299 ± 175 cm3, PTV:818 ± 206 cm3. Dose prescription was 66Gy in 33 fractions to mean PTV. Delivery was performed with two partial arcs with a 6 MV photon beam. Results From a dosimetric point of view, RA allowed us to respect most planning objectives on target volumes and organs at risk. In particular: for GTV D1% = 105.6 ± 1.7%, D99% = 96.7 ± 1.8%, D5%-D95% = 6.3 ± 1.4%; contra-lateral lung mean dose resulted in 13.7 ± 3.9Gy, for spinal cord D1% = 39.5 ± 4.0Gy, for heart V45Gy = 9.0 ± 7.0Gy, for esophagus D1% = 67.4 ± 2.2Gy. Delivery time was 133 ± 7s. At three months partial remission > 50% was observed in 56% of patients. Acute toxicities at 3 months showed 91% with grade 1 and 9% with grade 2 esophageal toxicity; 18% presented grade 1 and 9% with grade 2 pneumonia; no grade 3 acute toxicity was observed. The short follow-up does not allow assessment of local control and progression free survival. Conclusions RA proved to be a safe and advantageous treatment modality for NSCLC with large volumes. Long term observation of patients is needed to assess outcome and late toxicity.

  17. Relationship between CT visual score and lung volume which is measured by helium dilution method and body plethysmographic method in patients with pulmonary emphysema

    International Nuclear Information System (INIS)

    Toyoshima, Hideo; Ishibashi, Masayoshi; Senju, Syoji; Tanaka, Hideki; Aritomi, Takamichi; Watanabe, Kentaro; Yoshida, Minoru

    1997-01-01

    We examined the relationship between CT visual score and pulmonary function studies in patients with pulmonary emphysema. Lung volume was measured using helium dilution method and body plethysmographic method. Although airflow obstruction and overinflation measured by helium dilution method did not correlate with CT visual score, CO diffusing capacity per alveolar volume (DL CO /V A ) showed significant negative correlation with CT visual score (r=-0.49, p CO /V A reflect pathologic change in pulmonary emphysema. Further, both helium dilution method and body plethysmographic method are required to evaluate lung volume of pulmonary emphysema because of its ventilatory unevenness. (author)

  18. Limits of dose escalation in lung cancer: a dose-volume histogram analysis comparing coplanar and non-coplanar techniques

    Energy Technology Data Exchange (ETDEWEB)

    Derycke, S; Van Duyse, B; Schelfhout, J; De Neve, W

    1995-12-01

    To evaluate the feasibility of dose escalation in radiotherapy of inoperable lung cancer, a dose-volume histogram analysis was performed comparing standard coplanar (2D) with non-coplanar (3D) beam arrangements on a non-selected group of 20 patients planned by Sherouse`s GRATISTM 3D-planning system. Serial CT-scanning was performed and 2 Target Volumes (Tvs) were defined. Gross Tumor Volume (GTV) defined a high-dose Target Volume (TV-1). GTV plus location of node stations with > 10% probability of invasion (Minet et al.) defined an intermediate-dose Target Volume (TV-2). However, nodal regions which are incompatible with cure were excluded from TV-2. These are ATS-regions 1, 8, 9 and 14 all left and right as well as heterolateral regions. For 3D-planning, Beam`s Eye View selected (by an experienced planner) beam arrangements were optimised using Superdot, a method of target dose-gradient annihilation developed by Sherouse. A second 3D-planning was performed using 4 beam incidences with maximal angular separation. The linac`s isocenter for the optimal arrangement was located at the geometrical center of gravity of a tetraheder, the tetraheder`s comers being the consecutive positions of the virtual source. This ideal beam arrangement was approximated as close as possible, taking into account technical limitations (patient-couch-gantry collisions). Criteria for tolerance were met if no points inside the spinal cord exceeded 50 Gy and if at least 50% of the lung volume received less than 20Gy. If dose regions below 50 Gy were judged acceptable at TV-2, 2D- as well as 3D-plans allow safe escalation to 80 Gy at TV-1. When TV-2 needed to be encompassed by isodose surfaces exceeding 50Gy, 3D-plans were necessary to limit dose at the spinal cord below tolerance. For large TVs dose is limited by lung tolerance for 3D-plans. An analysis (including NTCP-TCP as cost functions) of rival 3D-plans is being performed.

  19. Lung

    International Nuclear Information System (INIS)

    DeNardo, G.L.; Blankenship, W.J.; Burdine, J.A. Jr.; DeNardo, S.J.

    1975-01-01

    At present no simple statement can be made relative to the role of radionuclidic lung studies in the pediatric population. It is safe to assume that they will be used with increasing frequency for research and clinical applications because of their sensitivity and ready applicability to the pediatric patient. Methods comparable to those used in adults can be used in children older than 4 years. In younger children, however, a single injection of 133 Xe in solution provides an index of both regional perfusion and ventilation which is easier to accomplish. This method is particularly valuable in infants and neonates because it is rapid, requires no patient cooperation, results in a very low radiation dose, and can be repeated in serial studies. Radionuclidic studies of ventilation and perfusion can be performed in almost all children if the pediatrician and the nuclear medicine specialist have motivation and ingenuity. S []ontaneous pulmonary vascular occlusive disease which occurs in infants and pulmonary emboli in children are easily detected using radionuclides. The pathophysiologic defects of pulmonary agenesis, bronchopulmonary sequestration, and foreign body aspiration may be demonstrated by these techniques. These techniques also appear to be useful in following patients with bronchial asthma, cystic fibrosis, congenital emphysema, and postinfection pulmonary abnormalities. (auth)

  20. High-Frequency Jet Ventilation for Complete Target Immobilization and Reduction of Planning Target Volume in Stereotactic High Single-Dose Irradiation of Stage I Non-Small Cell Lung Cancer and Lung Metastases

    International Nuclear Information System (INIS)

    Fritz, Peter; Kraus, Hans-Joerg; Muehlnickel, Werner; Sassmann, Volker; Hering, Werner; Strauch, Konstantin

    2010-01-01

    Purpose: To demonstrate the feasibility of complete target immobilization by means of high-frequency jet ventilation (HFJV); and to show that the saving of planning target volume (PTV) on the stereotactic body radiation therapy (SBRT) under HFJV, compared with SBRT with respiratory motion, can be predicted with reliable accuracy by computed tomography (CT) scans at peak inspiration phase. Methods and Materials: A comparison regarding different methods for defining the PTV was carried out in 22 patients with tumors that clearly moved with respiration. A movement span of the gross tumor volume (GTV) was defined by fusing respiration-correlated CT scans. The PTV enclosed the GTV positions with a safety margin throughout the breathing cycle. To create a PTV from CT scans acquired under HFJV, the same margins were drawn around the immobilized target. In addition, peak inspiration phase CT images (PIP-CTs) were used to approximate a target immobilized by HFJV. Results: The resulting HFJV-PTVs were between 11.6% and 45.4% smaller than the baseline values calculated as respiration-correlated CT-PTVs (median volume reduction, 25.4%). Tentative planning by means of PIP-CT PTVs predicted that in 19 of 22 patients, use of HFJV would lead to a reduction in volume of ≥20%. Using this threshold yielded a positive predictive value of 0.89, as well as a sensitivity of 0.94 and a specificity of 0.5. Conclusions: In all patients, SBRT under HFJV provided a reliable immobilization of the GTVs and achieved a reduction in PTVs, regardless of patient compliance. Tentative planning facilitated the selection of patients who could better undergo radiation in respiratory standstill, both with greater accuracy and lung protection.

  1. Study of 201 Non-Small Cell Lung Cancer Patients Given Stereotactic Ablative Radiation Therapy Shows Local Control Dependence on Dose Calculation Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Latifi, Kujtim, E-mail: Kujtim.Latifi@Moffitt.org [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida (United States); Oliver, Jasmine [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida (United States); Department of Physics, University of South Florida, Tampa, Florida (United States); Baker, Ryan [University of South Florida School of Medicine, Tampa, Florida (United States); Dilling, Thomas J.; Stevens, Craig W. [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida (United States); Kim, Jongphil; Yue, Binglin [Department of Biostatics and Bioinformatics, Moffitt Cancer Center, Tampa, Florida (United States); DeMarco, MaryLou; Zhang, Geoffrey G.; Moros, Eduardo G.; Feygelman, Vladimir [Department of Radiation Oncology, Moffitt Cancer Center, Tampa, Florida (United States)

    2014-04-01

    Purpose: Pencil beam (PB) and collapsed cone convolution (CCC) dose calculation algorithms differ significantly when used in the thorax. However, such differences have seldom been previously directly correlated with outcomes of lung stereotactic ablative body radiation (SABR). Methods and Materials: Data for 201 non-small cell lung cancer patients treated with SABR were analyzed retrospectively. All patients were treated with 50 Gy in 5 fractions of 10 Gy each. The radiation prescription mandated that 95% of the planning target volume (PTV) receive the prescribed dose. One hundred sixteen patients were planned with BrainLab treatment planning software (TPS) with the PB algorithm and treated on a Novalis unit. The other 85 were planned on the Pinnacle TPS with the CCC algorithm and treated on a Varian linac. Treatment planning objectives were numerically identical for both groups. The median follow-up times were 24 and 17 months for the PB and CCC groups, respectively. The primary endpoint was local/marginal control of the irradiated lesion. Gray's competing risk method was used to determine the statistical differences in local/marginal control rates between the PB and CCC groups. Results: Twenty-five patients planned with PB and 4 patients planned with the CCC algorithms to the same nominal doses experienced local recurrence. There was a statistically significant difference in recurrence rates between the PB and CCC groups (hazard ratio 3.4 [95% confidence interval: 1.18-9.83], Gray's test P=.019). The differences (Δ) between the 2 algorithms for target coverage were as follows: ΔD99{sub GITV} = 7.4 Gy, ΔD99{sub PTV} = 10.4 Gy, ΔV90{sub GITV} = 13.7%, ΔV90{sub PTV} = 37.6%, ΔD95{sub PTV} = 9.8 Gy, and ΔD{sub ISO} = 3.4 Gy. GITV = gross internal tumor volume. Conclusions: Local control in patients receiving who were planned to the same nominal dose with PB and CCC algorithms were statistically significantly different. Possible

  2. Considerations on the calculation of volumes in two planning systems; Consideraciones sobre el calculo de volumenes en dos sistemas de planificacion

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Tenedor Alonso, S.; Rincon Perez, M.; Penedo Cobos, J. M.; Garcia Castejon, M. A.

    2011-07-01

    The discrepancies in the calculation of the same volume between different planning systems impact on dose-volume histograms and therefore clinical assessment of dosimetry for patients. The transfer, by a local network, tomographic study (CT) and contours of critical organs of patients, between our two planning systems allows us to evaluate the calculation of identical volumes.

  3. Infusion volume control and calculation using metronome and drop counter based intravenous infusion therapy helper.

    Science.gov (United States)

    Park, Kyungnam; Lee, Jangyoung; Kim, Soo-Young; Kim, Jinwoo; Kim, Insoo; Choi, Seung Pill; Jeong, Sikyung; Hong, Sungyoup

    2013-06-01

    This study assessed the method of fluid infusion control using an IntraVenous Infusion Controller (IVIC). Four methods of infusion control (dial flow controller, IV set without correction, IV set with correction and IVIC correction) were used to measure the volume of each technique at two infusion rates. The infused fluid volume with a dial flow controller was significantly larger than other methods. The infused fluid volume was significantly smaller with an IV set without correction over time. Regarding the concordance correlation coefficient (CCC) of infused fluid volume in relation to a target volume, IVIC correction was shown to have the highest level of agreement. The flow rate measured in check mode showed a good agreement with the volume of collected fluid after passing through the IV system. Thus, an IVIC could assist in providing an accurate infusion control. © 2013 Wiley Publishing Asia Pty Ltd.

  4. A stable algorithm for calculating phase equilibria with capillarity at specified moles, volume and temperature using a dynamic model

    KAUST Repository

    Kou, Jisheng

    2017-09-30

    Capillary pressure can significantly affect the phase properties and flow of liquid-gas fluids in porous media, and thus, the phase equilibrium calculation incorporating capillary pressure is crucial to simulate such problems accurately. Recently, the phase equilibrium calculation at specified moles, volume and temperature (NVT-flash) becomes an attractive issue. In this paper, capillarity is incorporated into the phase equilibrium calculation at specified moles, volume and temperature. A dynamical model for such problem is developed for the first time by using the laws of thermodynamics and Onsager\\'s reciprocal principle. This model consists of the evolutionary equations for moles and volume, and it can characterize the evolutionary process from a non-equilibrium state to an equilibrium state in the presence of capillarity effect at specified moles, volume and temperature. The phase equilibrium equations are naturally derived. To simulate the proposed dynamical model efficiently, we adopt the convex-concave splitting of the total Helmholtz energy, and propose a thermodynamically stable numerical algorithm, which is proved to preserve the second law of thermodynamics at the discrete level. Using the thermodynamical relations, we derive a phase stability condition with capillarity effect at specified moles, volume and temperature. Moreover, we propose a stable numerical algorithm for the phase stability testing, which can provide the feasible initial conditions. The performance of the proposed methods in predicting phase properties under capillarity effect is demonstrated on various cases of pure substance and mixture systems.

  5. Abnormalities in lung volumes and airflow in children with newly diagnosed connective tissue disease.

    Science.gov (United States)

    Peradzyńska, Joanna; Krenke, Katarzyna; Szylling, Anna; Kołodziejczyk, Beata; Gazda, Agnieszka; Rutkowska-Sak, Lidia; Kulus, Marek

    2016-01-01

    Connective tissue diseases (CTDs) of childhood are rare inflammatory disorders, involving various organs and tissues including respiratory system. Pulmonary involvement in patients with CTDs is uncommon but may cause functional impairment. Data on prevalence and type of lung function abnormalities in children with CTDs are scarce. Thus, the aim of this study was to asses pulmonary functional status in children with newly diagnosed CTD and follow the results after two years of the disease course. There were 98 children (mean age: 13 ± 3; 76 girls), treated in Department of Pediatric Rheumatology, Institute of Rheumatology, Warsaw and 80 aged-matched, healthy controls (mean age 12.7 ± 2.4; 50 girls) included into the study. Study procedures included medical history, physical examination, chest radiograph and PFT (spirometry and whole body-plethysmography). Then, the assessment of PFT was performed after 24 months. FEV₁, FEV₁/FVC and MEF50 were significantly lower in CTD as compared to control group, there was no difference in FVC and TLC. The proportion of patients with abnormal lung function was significantly higher in the study group, 41 (42%) vs 9 (11%). 24-months observation didn't reveal progression in lung function impairment. Lung function impairment is relatively common in children with CTDs. Although restrictive ventilatory pattern is considered typical feature of lung involvement in CTDs, airflow limitation could also be an initial abnormality.

  6. Inflation and deflation pressure-volume loops in anesthetized pinnipeds confirms compliant chest and lungs.

    Science.gov (United States)

    Fahlman, Andreas; Loring, Stephen H; Johnson, Shawn P; Haulena, Martin; Trites, Andrew W; Fravel, Vanessa A; Van Bonn, William G

    2014-01-01

    We examined structural properties of the marine mammal respiratory system, and tested Scholander's hypothesis that the chest is highly compliant by measuring the mechanical properties of the respiratory system in five species of pinniped under anesthesia (Pacific harbor seal, Phoca vitulina; northern elephant seal, Mirounga angustirostris; northern fur seal Callorhinus ursinus; California sea lion, Zalophus californianus; and Steller sea lion, Eumetopias jubatus). We found that the chest wall compliance (CCW) of all five species was greater than lung compliance (airways and alveoli, CL) as predicted by Scholander, which suggests that the chest provides little protection against alveolar collapse or lung squeeze. We also found that specific respiratory compliance was significantly greater in wild animals than in animals raised in an aquatic facility. While differences in ages between the two groups may affect this incidental finding, it is also possible that lung conditioning in free-living animals may increase pulmonary compliance and reduce the risk of lung squeeze during diving. Overall, our data indicate that compliance of excised pinniped lungs provide a good estimate of total respiratory compliance.

  7. Inflation and deflation pressure-volume loops in anesthetized pinnipeds confirms compliant chest and lungs

    Directory of Open Access Journals (Sweden)

    Andreas eFahlman

    2014-11-01

    Full Text Available We examined structural properties of the marine mammal respiratory system, and tested Scholander’s hypothesis that the chest is highly compliant by measuring the mechanical properties of the respiratory system in five species of pinniped under anesthesia (Pacific harbor seal, Phoca vitulina; northern elephant seal, Mirounga angustirostris; northern fur seal Callorhinus ursinus; California sea lion, Zalophus californianus; and Steller sea lion, Eumetopias jubatus. We found that the chest wall compliance (CCW of all five species was greater than lung compliance (airways and alveoli, CL as predicted by Scholander, which suggests that the chest provides little protection against alveolar collapse or lung squeeze. We also found that specific respiratory compliance was significantly greater in wild animals than in animals raised under human care. While differences in ages between the two groups may affect this incidental finding, it is also possible that lung conditioning in free-living animals may increase pulmonary compliance and reduce the risk of lung squeeze during diving. Overall, our data indicate that compliance of excised pinniped lungs provide a good estimate of total respiratory compliance.

  8. Craniocaudal Safety Margin Calculation Based on Interfractional Changes in Tumor Motion in Lung SBRT Assessed With an EPID in Cine Mode

    International Nuclear Information System (INIS)

    Ueda, Yoshihiro; Miyazaki, Masayoshi; Nishiyama, Kinji; Suzuki, Osamu; Tsujii, Katsutomo; Miyagi, Ken

    2012-01-01

    Purpose: To evaluate setup error and interfractional changes in tumor motion magnitude using an electric portal imaging device in cine mode (EPID cine) during the course of stereotactic body radiation therapy (SBRT) for non–small-cell lung cancer (NSCLC) and to calculate margins to compensate for these variations. Materials and Methods: Subjects were 28 patients with Stage I NSCLC who underwent SBRT. Respiratory-correlated four-dimensional computed tomography (4D-CT) at simulation was binned into 10 respiratory phases, which provided average intensity projection CT data sets (AIP). On 4D-CT, peak-to-peak motion of the tumor (M-4DCT) in the craniocaudal direction was assessed and the tumor center (mean tumor position [MTP]) of the AIP (MTP-4DCT) was determined. At treatment, the tumor on cone beam CT was registered to that on AIP for patient setup. During three sessions of irradiation, peak-to-peak motion of the tumor (M-cine) and the mean tumor position (MTP-cine) were obtained using EPID cine and in-house software. Based on changes in tumor motion magnitude (∆M) and patient setup error (∆MTP), defined as differences between M-4DCT and M-cine and between MTP-4DCT and MTP-cine, a margin to compensate for these variations was calculated with Stroom’s formula. Results: The means (±standard deviation: SD) of M-4DCT and M-cine were 3.1 (±3.4) and 4.0 (±3.6) mm, respectively. The means (±SD) of ∆M and ∆MTP were 0.9 (±1.3) and 0.2 (±2.4) mm, respectively. Internal target volume-planning target volume (ITV-PTV) margins to compensate for ∆M, ∆MTP, and both combined were 3.7, 5.2, and 6.4 mm, respectively. Conclusion: EPID cine is a useful modality for assessing interfractional variations of tumor motion. The ITV-PTV margins to compensate for these variations can be calculated.

  9. New reference charts for testicular volume in Dutch children and adolescents allow the calculation of standard deviation scores.

    Science.gov (United States)

    Joustra, Sjoerd D; van der Plas, Evelyn M; Goede, Joery; Oostdijk, Wilma; Delemarre-van de Waal, Henriette A; Hack, Wilfried W M; van Buuren, Stef; Wit, Jan M

    2015-06-01

    Accurate calculations of testicular volume standard deviation (SD) scores are not currently available. We constructed LMS-smoothed age-reference charts for testicular volume in healthy boys. The LMS method was used to calculate reference data, based on testicular volumes from ultrasonography and Prader orchidometer of 769 healthy Dutch boys aged 6 months to 19 years. We also explored the association between testicular growth and pubic hair development, and data were compared to orchidometric testicular volumes from the 1997 Dutch nationwide growth study. The LMS-smoothed reference charts showed that no revision of the definition of normal onset of male puberty - from nine to 14 years of age - was warranted. In healthy boys, the pubic hair stage SD scores corresponded with testicular volume SD scores (r = 0.394). However, testes were relatively small for pubic hair stage in Klinefelter's syndrome and relatively large in immunoglobulin superfamily member 1 deficiency syndrome. The age-corrected SD scores for testicular volume will aid in the diagnosis and follow-up of abnormalities in the timing and progression of male puberty and in research evaluations. The SD scores can be compared with pubic hair SD scores to identify discrepancies between cell functions that result in relative microorchidism or macroorchidism. ©2015 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  10. Uranium Mill Tailings Remedial Action Project (UMTRAP), Slick Rock, Colorado, Revision 1. Volume 2, Calculations, Final design for construction

    International Nuclear Information System (INIS)

    1995-09-01

    Volume two contains calculations for: embankment design--slope stability analysis; embankment design--excavation stability; embankment design--settlement and cover cracking analysis; radon barrier design--statistical analysis of ra-226 concentrations for North Continent and Union Carbide sites; radon barrier design--RAECOM input data; radon barrier design--design thickness; and cover design--frost penetration depth

  11. Uranium Mill Tailings Remedial Action Project (UMTRAP), Slick Rock, Colorado, Revision 1, Volume 4. Calculations, Final design for construction

    International Nuclear Information System (INIS)

    1995-09-01

    Volume four contains calculations for: Borrow areas--site evaluation; temporary facilities--material quantities; embankment quantities--excavation and cover materials; Burro Canyon site excavation quantities--rippable and unrippable materials; site restoration--earthwork quantities and seeding; and bid schedule quantities and material balance

  12. Nonlinear effects at volume charge polarization and calculation of the structure radiation changes in the crystals with hydrogen bonds

    International Nuclear Information System (INIS)

    Tonkonogov, M.P.; Medvedev, V.Ya.

    2003-01-01

    The formulas for volume charge distribution, complex permittivity, static dielectric constant for the crystals with hydrogen bonds are proposed. With help of the formulas the structure defect concentration, relaxation energy of relaxators were calculated for important electronic and optoelectronic materials as mica, KDP and DKDP crystals, gypsum, talk

  13. Positron emission tomography of the lung

    International Nuclear Information System (INIS)

    Wollmer, P.

    1984-01-01

    Positron emission tomography enables the distribution of positron emitting isotopes to be imaged in a transverse plane through the body and the regional concentration of the isotope to be measured quantitatively. This thesis reports some applications of positron emission tomography to studies of pulmonary pathophysiology. Measurements in lung phantoms showed that regional lung density could be measured from a transmission tomogram obtained with an external source of positron emitting isotope. The regional, fractional blood volume was measured after labelling the blood with carbon-11-monoxide. Regional extravascular lung density (lung tissue and interstitial water per unit thoracic volume) was obtained by subtracting fractional blood volume from lung density. Measurements in normal subjects revealed large regional variations in lung density and fractional blood volume in the supine posture. Extravascular lung density showed a more uniform distribution. The technique has been used to study patients with chronic interstitial pulmonary oedema, pulmonary sarcoidosis and fibrosis, pulmonary arterial hypertension and patients with intracardiac, left-to-right shunt. Tomographic measurements of pulmonary tissue concentration of radionuclides are difficult, since corrections for the blood content and the inflation of the lung must be applied. A simultaneous measurement of lung density and fractional blood volume allows such corrections to be made and the extravascular tracer concentration to be calculated. This has been applied to measurements of the tissue penetration of carbon-11-labelled erythromycin in patients with lobar pneumonia. (author)

  14. SU-E-J-30: Benchmark Image-Based TCP Calculation for Evaluation of PTV Margins for Lung SBRT Patients

    Energy Technology Data Exchange (ETDEWEB)

    Li, M [Wayne State Univeristy, Detroit, MI (United States); Chetty, I [Henry Ford Health System, Detroit, MI (United States); Zhong, H [Henry Ford Hospital System, Detroit, MI (United States)

    2014-06-01

    Purpose: Tumor control probability (TCP) calculated with accumulated radiation doses may help design appropriate treatment margins. Image registration errors, however, may compromise the calculated TCP. The purpose of this study is to develop benchmark CT images to quantify registration-induced errors in the accumulated doses and their corresponding TCP. Methods: 4DCT images were registered from end-inhale (EI) to end-exhale (EE) using a “demons” algorithm. The demons DVFs were corrected by an FEM model to get realistic deformation fields. The FEM DVFs were used to warp the EI images to create the FEM-simulated images. The two images combined with the FEM DVF formed a benchmark model. Maximum intensity projection (MIP) images, created from the EI and simulated images, were used to develop IMRT plans. Two plans with 3 and 5 mm margins were developed for each patient. With these plans, radiation doses were recalculated on the simulated images and warped back to the EI images using the FEM DVFs to get the accumulated doses. The Elastix software was used to register the FEM-simulated images to the EI images. TCPs calculated with the Elastix-accumulated doses were compared with those generated by the FEM to get the TCP error of the Elastix registrations. Results: For six lung patients, the mean Elastix registration error ranged from 0.93 to 1.98 mm. Their relative dose errors in PTV were between 0.28% and 6.8% for 3mm margin plans, and between 0.29% and 6.3% for 5mm-margin plans. As the PTV margin reduced from 5 to 3 mm, the mean TCP error of the Elastix-reconstructed doses increased from 2.0% to 2.9%, and the mean NTCP errors decreased from 1.2% to 1.1%. Conclusion: Patient-specific benchmark images can be used to evaluate the impact of registration errors on the computed TCPs, and may help select appropriate PTV margins for lung SBRT patients.

  15. SU-E-J-30: Benchmark Image-Based TCP Calculation for Evaluation of PTV Margins for Lung SBRT Patients

    International Nuclear Information System (INIS)

    Li, M; Chetty, I; Zhong, H

    2014-01-01

    Purpose: Tumor control probability (TCP) calculated with accumulated radiation doses may help design appropriate treatment margins. Image registration errors, however, may compromise the calculated TCP. The purpose of this study is to develop benchmark CT images to quantify registration-induced errors in the accumulated doses and their corresponding TCP. Methods: 4DCT images were registered from end-inhale (EI) to end-exhale (EE) using a “demons” algorithm. The demons DVFs were corrected by an FEM model to get realistic deformation fields. The FEM DVFs were used to warp the EI images to create the FEM-simulated images. The two images combined with the FEM DVF formed a benchmark model. Maximum intensity projection (MIP) images, created from the EI and simulated images, were used to develop IMRT plans. Two plans with 3 and 5 mm margins were developed for each patient. With these plans, radiation doses were recalculated on the simulated images and warped back to the EI images using the FEM DVFs to get the accumulated doses. The Elastix software was used to register the FEM-simulated images to the EI images. TCPs calculated with the Elastix-accumulated doses were compared with those generated by the FEM to get the TCP error of the Elastix registrations. Results: For six lung patients, the mean Elastix registration error ranged from 0.93 to 1.98 mm. Their relative dose errors in PTV were between 0.28% and 6.8% for 3mm margin plans, and between 0.29% and 6.3% for 5mm-margin plans. As the PTV margin reduced from 5 to 3 mm, the mean TCP error of the Elastix-reconstructed doses increased from 2.0% to 2.9%, and the mean NTCP errors decreased from 1.2% to 1.1%. Conclusion: Patient-specific benchmark images can be used to evaluate the impact of registration errors on the computed TCPs, and may help select appropriate PTV margins for lung SBRT patients

  16. An evaluation of an automated 4D-CT contour propagation tool to define an internal gross tumour volume for lung cancer radiotherapy

    International Nuclear Information System (INIS)

    Gaede, Stewart; Olsthoorn, Jason; Louie, Alexander V.; Palma, David; Yu, Edward; Yaremko, Brian; Ahmad, Belal; Chen, Jeff; Bzdusek, Karl; Rodrigues, George

    2011-01-01

    Background and purpose: To evaluate an automated 4D-CT contouring propagation tool by its impact on the inter- and intra-physician variability in lung tumour delineation. Materials and methods: In a previous study, six radiation oncologists contoured the gross tumour volume (GTV) and nodes on 10 phases of the 4D-CT dataset of 10 lung cancer patients to examine the intra- and inter-physician variability. In this study, a model-based deformable image registration algorithm was used to propagate the GTV and nodes on each phase of the same 4D-CT datasets. A blind review of the contours was performed by each physician and edited. Inter- and intra-physician variability for both the manual and automated methods was assessed by calculating the centroid motion of the GTV using the Pearson correlation coefficient and the variability in the internal gross tumour volume (IGTV) overlap using the Dice similarity coefficient (DSC). Results: The time for manual delineation was (42.7 ± 18.6) min versus (17.7 ± 5.4) min when the propagation tool was used. A significant improvement in the mean Pearson correlation coefficient was also observed. There was a significant decrease in mean DSC in only 1 out of 10 primary IGTVs and 2 out of 10 nodal IGTVs. Intra-physician variability was not significantly impacted (DSC > 0.742). Conclusions: Automated 4D-CT propagation tools can significantly decrease the IGTV delineation time without significantly decreasing the inter- and intra-physician variability.

  17. Heliox allows for lower minute volume ventilation in an animal model of ventilator-induced lung injury.

    Directory of Open Access Journals (Sweden)

    Charlotte J Beurskens

    Full Text Available BACKGROUND: Helium is a noble gas with a low density, allowing for lower driving pressures and increased carbon dioxide (CO2 diffusion. Since application of protective ventilation can be limited by the development of hypoxemia or acidosis, we hypothesized that therefore heliox facilitates ventilation in an animal model of ventilator-induced lung injury. METHODS: Sprague-Dawley rats (N=8 per group were mechanically ventilated with heliox (50% oxygen; 50% helium. Controls received a standard gas mixture (50% oxygen; 50% air. VILI was induced by application of tidal volumes of 15 mL kg(-1; lung protective ventilated animals were ventilated with 6 mL kg(-1. Respiratory parameters were monitored with a pneumotach system. Respiratory rate was adjusted to maintain arterial pCO2 within 4.5-5.5 kPa, according to hourly drawn arterial blood gases. After 4 hours, bronchoalveolar lavage fluid (BALF was obtained. Data are mean (SD. RESULTS: VILI resulted in an increase in BALF protein compared to low tidal ventilation (629 (324 vs. 290 (181 μg mL(-1; p<0.05 and IL-6 levels (640 (8.7 vs. 206 (8.7 pg mL(-1; p<0.05, whereas cell counts did not differ between groups after this short course of mechanical ventilation. Ventilation with heliox resulted in a decrease in mean respiratory minute volume ventilation compared to control (123 ± 0.6 vs. 146 ± 8.9 mL min(-1, P<0.001, due to a decrease in respiratory rate (22 (0.4 vs. 25 (2.1 breaths per minute; p<0.05, while pCO2 levels and tidal volumes remained unchanged, according to protocol. There was no effect of heliox on inspiratory pressure, while compliance was reduced. In this mild lung injury model, heliox did not exert anti-inflammatory effects. CONCLUSIONS: Heliox allowed for a reduction in respiratory rate and respiratory minute volume during VILI, while maintaining normal acid-base balance. Use of heliox may be a useful approach when protective tidal volume ventilation is limited by the development of

  18. Estimation of Lung Ventilation

    Science.gov (United States)

    Ding, Kai; Cao, Kunlin; Du, Kaifang; Amelon, Ryan; Christensen, Gary E.; Raghavan, Madhavan; Reinhardt, Joseph M.

    Since the primary function of the lung is gas exchange, ventilation can be interpreted as an index of lung function in addition to perfusion. Injury and disease processes can alter lung function on a global and/or a local level. MDCT can be used to acquire multiple static breath-hold CT images of the lung taken at different lung volumes, or with proper respiratory control, 4DCT images of the lung reconstructed at different respiratory phases. Image registration can be applied to this data to estimate a deformation field that transforms the lung from one volume configuration to the other. This deformation field can be analyzed to estimate local lung tissue expansion, calculate voxel-by-voxel intensity change, and make biomechanical measurements. The physiologic significance of the registration-based measures of respiratory function can be established by comparing to more conventional measurements, such as nuclear medicine or contrast wash-in/wash-out studies with CT or MR. An important emerging application of these methods is the detection of pulmonary function change in subjects undergoing radiation therapy (RT) for lung cancer. During RT, treatment is commonly limited to sub-therapeutic doses due to unintended toxicity to normal lung tissue. Measurement of pulmonary function may be useful as a planning tool during RT planning, may be useful for tracking the progression of toxicity to nearby normal tissue during RT, and can be used to evaluate the effectiveness of a treatment post-therapy. This chapter reviews the basic measures to estimate regional ventilation from image registration of CT images, the comparison of them to the existing golden standard and the application in radiation therapy.

  19. Observer variation in target volume delineation of lung cancer related to radiation oncologist-computer interaction: A 'Big Brother' evaluation

    International Nuclear Information System (INIS)

    Steenbakkers, Roel J.H.M.; Duppen, Joop C.; Fitton, Isabelle; Deurloo, Kirsten E.I.; Zijp, Lambert; Uitterhoeve, Apollonia L.J.; Rodrigus, Patrick T.R.; Kramer, Gijsbert W.P.; Bussink, Johan; Jaeger, Katrien De; Belderbos, Jose S.A.; Hart, Augustinus A.M.; Nowak, Peter J.C.M.; Herk, Marcel van; Rasch, Coen R.N.

    2005-01-01

    Background and purpose: To evaluate the process of target volume delineation in lung cancer for optimization of imaging, delineation protocol and delineation software. Patients and methods: Eleven radiation oncologists (observers) from five different institutions delineated the Gross Tumor Volume (GTV) including positive lymph nodes of 22 lung cancer patients (stages I-IIIB) on CT only. All radiation oncologist-computer interactions were recorded with a tool called 'Big Brother'. For each radiation oncologist and patient the following issues were analyzed: delineation time, number of delineated points and corrections, zoom levels, level and window (L/W) settings, CT slice changes, use of side windows (coronal and sagittal) and software button use. Results: The mean delineation time per GTV was 16 min (SD 10 min). The mean delineation time for lymph node positive patients was on average 3 min larger (P=0.02) than for lymph node negative patients. Many corrections (55%) were due to L/W change (e.g. delineating in mediastinum L/W and then correcting in lung L/W). For the lymph node region, a relatively large number of corrections was found (3.7 corr/cm 2 ), indicating that it was difficult to delineate lymph nodes. For the tumor-atelectasis region, a relative small number of corrections was found (1.0 corr/cm 2 ), indicating that including or excluding atelectasis into the GTV was a clinical decision. Inappropriate use of L/W settings was frequently found (e.g. 46% of all delineated points in the tumor-lung region were delineated in mediastinum L/W settings). Despite a large observer variation in cranial and caudal direction of 0.72 cm (1 SD), the coronal and sagittal side windows were not used in 45 and 60% of the cases, respectively. For the more difficult cases, observer variation was smaller when the coronal and sagittal side windows were used. Conclusions: With the 'Big Brother' tool a method was developed to trace the delineation process. The differences between

  20. Calculating excess volumes of binary solutions with allowance for structural differences between mixed components

    Science.gov (United States)

    Balankina, E. S.

    2016-06-01

    Analytical dependences of a volume's properties on the differences between the geometric structures of initial monosystems are obtained for binary systems simulated by a grain medium. The effect of microstructural parameter k (the ratio of volumes of molecules of mixed components) on the concentration behavior of the relative excess molar volume of different types of real binary solutions is analyzed. It is established that the contribution due to differences between the volumes of molecules and coefficients of the packing density of mixed components is ~80-100% for mutual solutions of n-alkanes and ~55-80% of the experimental value of the relative excess molar volume for water solutions of n-alcohols.

  1. 3-D volume rendering visualization for calculated distributions of diesel spray; Diesel funmu kyodo suchi keisan kekka no sanjigen volume rendering hyoji

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizaki, T; Imanishi, H; Nishida, K; Yamashita, H; Hiroyasu, H; Kaneda, K [Hiroshima University, Hiroshima (Japan)

    1997-10-01

    Three dimensional visualization technique based on volume rendering method has been developed in order to translate calculated results of diesel combustion simulation into realistically spray and flame images. This paper presents an overview of diesel combustion model which has been developed at Hiroshima University, a description of the three dimensional visualization technique, and some examples of spray and flame image generated by this visualization technique. 8 refs., 8 figs., 1 tab.

  2. Geographic miss of lung tumours due to respiratory motion: a comparison of 3D vs 4D PET/CT defined target volumes

    International Nuclear Information System (INIS)

    Callahan, Jason; Kron, Tomas; Siva, Shankar; Simoens, Nathalie; Edgar, Amanda; Everitt, Sarah; Schneider, Michal E; Hicks, Rodney J

    2014-01-01

    PET/CT scans acquired in the radiotherapy treatment position are typically performed without compensating for respiratory motion. The purpose of this study was to investigate geographic miss of lung tumours due to respiratory motion for target volumes defined on a standard 3D-PET/CT. 29 patients staged for pulmonary malignancy who completed both a 3D-PET/CT and 4D-PET/CT were included. A 3D-Gross Tumour Volume (GTV) was defined on the standard whole body PET/CT scan. Subsequently a 4D-GTV was defined on a 4D-PET/CT MIP. A 5 mm, 10 mm, 15 mm symmetrical and 15×10 mm asymmetrical Planning Target Volume (PTV) was created by expanding the 3D-GTV and 4D-GTV’s. A 3D conformal plan was generated and calculated to cover the 3D-PTV. The 3D plan was transferred to the 4D-PTV and analysed for geographic miss. Three types of miss were measured. Type 1: any part of the 4D-GTV outside the 3D-PTV. Type 2: any part of the 4D-PTV outside the 3D-PTV. Type 3: any part of the 4D-PTV receiving less than 95% of the prescribed dose. The lesion motion was measured to look at the association between lesion motion and geographic miss. When a standard 15 mm or asymmetrical PTV margin was used there were 1/29 (3%) Type 1 misses. This increased 7/29 (24%) for the 10 mm margin and 23/29 (79%) for a 5 mm margin. All patients for all margins had a Type 2 geographic miss. There was a Type 3 miss in 25 out of 29 cases in the 5, 10, and 15 mm PTV margin groups. The asymmetrical margin had one additional Type 3 miss. Pearson analysis showed a correlation (p < 0.01) between lesion motion and the severity of the different types of geographic miss. Without any form of motion suppression, the current standard of a 3D- PET/CT and 15 mm PTV margin employed for lung lesions has an increasing risk of significant geographic miss when tumour motion increases. Use of smaller asymmetric margins in the cranio-caudal direction does not comprise tumour coverage. Reducing PTV margins for volumes defined on 3D

  3. SACALCCYL, Calculates the average solid angle subtended by a volume; SACALC2B, Calculates the average solid angle for source-detector geometries

    International Nuclear Information System (INIS)

    Whitcher, Ralph

    2007-01-01

    1 - Description of program or function: SACALC2B calculates the average solid angle subtended by a rectangular or circular detector window to a coaxial or non-coaxial rectangular, circular or point source, including where the source and detector planes are not parallel. SACALC C YL calculates the average solid angle subtended by a cylinder to a rectangular or circular source, plane or thick, at any location and orientation. This is needed, for example, in calculating the intrinsic gamma efficiency of a detector such as a GM tube. The program also calculates the number of hits on the cylinder side and on each end, and the average path length through the detector volume (assuming no scattering or absorption). Point sources can be modelled by using a circular source of zero radius. NEA-1688/03: Documentation has been updated (January 2006). 2 - Methods: The program uses a Monte Carlo method to calculate average solid angle for