Science.gov

Sample records for perfusion lung scan

  1. Lung Ventilation/Perfusion Scan

    MedlinePlus

    ... from the NHLBI on Twitter. What Is a Lung Ventilation/Perfusion Scan? A lung ventilation/perfusion scan, or VQ scan, is a ... that measures air and blood flow in your lungs. A VQ scan most often is used to ...

  2. Pulmonary ventilation/perfusion scan

    MedlinePlus

    V/Q scan; Ventilation/perfusion scan; Lung ventilation/perfusion scan ... A pulmonary ventilation/perfusion scan is actually two tests. They may be done separately or together. During the perfusion scan, a health care ...

  3. Prediction of postoperative loss of lung function in patients with malignant lung mass. Quantitative regional ventilation-perfusion scanning

    SciTech Connect

    Ryo, U.Y. )

    1990-05-01

    The quantitative measurement of regional ventilation and perfusion distribution is simply and reliably accomplished by using routinely available radioactive gas and perfusion lung scanning agents, and a large field-of-view gamma camera with an on-line computer. The preoperative prediction of postsurgical loss in lung function can be made accurately by using the quantitative ventilation-perfusion lung scan technique. Either a regional ventilation study or perfusion study may be used for the prediction, but analysis of regional ventilation distribution appears to be a better parameter than that of perfusion distribution for the prediction of postoperative loss of FEV1. In the rare case of a patient with a marked ventilation-perfusion deficit, quantitative distribution of both ventilation and perfusion may be needed for an accurate assessment of postsurgical lung function. 18 references.

  4. Clinical validity of a normal perfusion lung scan in patients with suspected pulmonary embolism.

    PubMed

    Hull, R D; Raskob, G E; Coates, G; Panju, A A

    1990-01-01

    The objective of this study was to test the safety of withholding anticoagulant therapy in patients with clinically suspected pulmonary embolism who have normal perfusion lung scans, regardless of the clinical manifestations. Anticoagulant therapy was withheld or withdrawn in 515 consecutive patients except in patients in whom deep-vein thrombosis was detected. Only three of the 515 patients had symptomatic venous thromboembolism on follow-up. The frequency of symptomatic pulmonary embolism on follow-up was one of 515 patients. With knowledge of the normal findings by perfusion scanning, an alternative diagnosis was established in 367 of the 515 patients. Cause of symptoms remained uncertain in 148 patients. It is safe to withhold anticoagulant therapy in patients with suspected pulmonary embolism and normal perfusion scans, regardless of the clinical manifestations. The finding of a normal perfusion scan excludes the presence of clinically important pulmonary embolism and makes pulmonary angiography unnecessary.

  5. Reversibility of intrapulmonary arteriovenous shunts in liver cirrhosis documented by serial radionuclide perfusion lung scans

    SciTech Connect

    Chen, N.S.; Barnett, C.A.; Farrer, P.A.

    1984-05-01

    Using serial perfusion lung scans, the opening up and closure of right-to-left intrapulmonary arteriovenous shunts has been documented over a period of several weeks in a patient with chronic alcoholic liver disease. The presence of the shunts correlates well with the severity of hypoxemia and the presence of nodular mottling on chest radiographs. The time course of these changes with clinical status suggests lability and the functional nature of these shunts.

  6. Lung scans with significant perfusion defects limited to matching pleural effusions have a low probability of pulmonary embolism

    SciTech Connect

    Datz, F.L.; Bedont, R.A.; Taylor, A.

    1985-05-01

    Patients with a pleural effusion on chest x-ray often undergo a lung scan to exclude pulmonary embolism (PE). According to other studies, when the scan shows a perfusion defect equal in size to a radiographic abnormality on chest x-ray, the scan should be classified as indeterminate or intermediate probability for PE. However, since those studies dealt primarily with alveolar infiltrates rather than pleural effusions, the authors undertook a retrospective study to determine the probability of PE in patients with pleural effusion and a matching perfusion defect. The authors reviewed 451 scans and x-rays of patients studied for suspected PE. Of those, 53 had moderate or large perfusion defects secondary to pleural effusion without other significant (>25% of a segment) effusion without other significant (>25% of a segment) defects on the scan. Final diagnosis was confirmed by pulmonary angiography (16), thoracentesis (40), venography (11), other radiographic and laboratory studies, and clinical course. Of the 53 patients, only 2 patients had venous thrombotic disease. One patient had PE on pulmonary angiography, the other patient had thrombophlebitis on venography. The remainder of the patients had effusions due to congestive heart failure (12), malignancy (12), infection (7), trauma (7), collegen vascular disease (7), sympathetic effusion (3) and unknown etiology (3). The authors conclude that lung scans with significant perfusion defects limited to matching pleural effusions on chest x-ray have a low probability for PE.

  7. Ex vivo lung perfusion.

    PubMed

    Reeb, Jeremie; Cypel, Marcelo

    2016-03-01

    Lung transplantation is an established life-saving therapy for patients with end-stage lung disease. Unfortunately, greater success in lung transplantation is hindered by a shortage of lung donors and the relatively poor early-, mid-, and long-term outcomes associated with severe primary graft dysfunction. Ex vivo lung perfusion has emerged as a modern preservation technique that allows for a more accurate lung assessment and improvement in lung quality. This review outlines the: (i) rationale behind the method; (ii) techniques and protocols; (iii) Toronto ex vivo lung perfusion method; (iv) devices available; and (v) clinical experience worldwide. We also highlight the potential of ex vivo lung perfusion in leading a new era of lung preservation. PMID:26700566

  8. Isolated lung perfusion.

    PubMed

    Cypel, Marcelo; Keshavjee, Shaf

    2012-01-01

    Isolated lung perfusion (ILP) has been historically used as a method to study basic lung physiologic concepts using animal models. More recently, ILP has been applied in lung transplantation and thoracic oncology. In lung transplantation, ILP has been used to assess physiological integrity of donor lungs after the organ is removed from the donor. This procedure is called Ex vivo Lung Perfusion (EVLP), and it has also been proposed as a method for active treatment and repair of injured unsuitable donor organs ex vivo. In oncology, ILP is an attractive method to deliver high dose chemotherapy to treat pulmonary metastatic disease. Since the lung vasculature is isolated in vivo, this technique is called in vivo lung perfusion (IVLP). This review will focus on the rationale, technical aspects, experimental and clinical experience of EVLP and IVLP. A perspective on the future use of these techniques is described. PMID:22202033

  9. Feasibility of quantitative lung perfusion by 4D CT imaging by a new dynamic-scanning protocol in an animal model

    NASA Astrophysics Data System (ADS)

    Wang, Yang; Goldin, Jonathan G.; Abtin, Fereidoun G.; Brown, Matt; McNitt-Gray, Mike

    2008-03-01

    The purpose of this study is to test a new dynamic Perfusion-CT imaging protocol in an animal model and investigate the feasibility of quantifying perfusion of lung parenchyma to perform functional analysis from 4D CT image data. A novel perfusion-CT protocol was designed with 25 scanning time points: the first at baseline and 24 scans after a bolus injection of contrast material. Post-contrast CT scanning images were acquired with a high sampling rate before the first blood recirculation and then a relatively low sampling rate until 10 minutes after administrating contrast agent. Lower radiation techniques were used to keep the radiation dose to an acceptable level. 2 Yorkshire swine with pulmonary emboli underwent this perfusion- CT protocol at suspended end inspiration. The software tools were designed to measure the quantitative perfusion parameters (perfusion, permeability, relative blood volume, blood flow, wash-in & wash-out enhancement) of voxel or interesting area of lung. The perfusion values were calculated for further lung functional analysis and presented visually as contrast enhancement maps for the volume being examined. The results show increased CT temporal sampling rate provides the feasibility of quantifying lung function and evaluating the pulmonary emboli. Differences between areas with known perfusion defects and those without perfusion defects were observed. In conclusion, the techniques to calculate the lung perfusion on animal model have potential application in human lung functional analysis such as evaluation of functional effects of pulmonary embolism. With further study, these techniques might be applicable in human lung parenchyma characterization and possibly for lung nodule characterization.

  10. Ex vivo lung perfusion.

    PubMed

    Machuca, Tiago N; Cypel, Marcelo

    2014-08-01

    Lung transplantation (LTx) is an established treatment option for eligible patients with end-stage lung disease. Nevertheless, the imbalance between suitable donor lungs available and the increasing number of patients considered for LTx reflects in considerable waitlist mortality. Among potential alternatives to address this issue, ex vivo lung perfusion (EVLP) has emerged as a modern preservation technique that allows for more accurate lung assessment and also improvement of lung function. Its application in high-risk donor lungs has been successful and resulted in safe expansion of the donor pool. This article will: (I) review the technical details of EVLP; (II) the rationale behind the method; (III) report the worldwide clinical experience with the EVLP, including the Toronto technique and others; (IV) finally, discuss the growing literature on EVLP application for donation after cardiac death (DCD) lungs. PMID:25132972

  11. Ex vivo lung perfusion

    PubMed Central

    Machuca, Tiago N.

    2014-01-01

    Lung transplantation (LTx) is an established treatment option for eligible patients with end-stage lung disease. Nevertheless, the imbalance between suitable donor lungs available and the increasing number of patients considered for LTx reflects in considerable waitlist mortality. Among potential alternatives to address this issue, ex vivo lung perfusion (EVLP) has emerged as a modern preservation technique that allows for more accurate lung assessment and also improvement of lung function. Its application in high-risk donor lungs has been successful and resulted in safe expansion of the donor pool. This article will: (I) review the technical details of EVLP; (II) the rationale behind the method; (III) report the worldwide clinical experience with the EVLP, including the Toronto technique and others; (IV) finally, discuss the growing literature on EVLP application for donation after cardiac death (DCD) lungs. PMID:25132972

  12. Quantitative study of lung perfusion SPECT scanning and pulmonary function testing for early radiation-induced lung injury in patients with locally advanced non-small cell lung cancer

    PubMed Central

    ZHANG, WEI; WANG, JIEZHONG; TANG, MINGDENG; PAN, JIANJI; BAI, PENGGANG; LIN, DUANYU; QIAN, FEIYU; LIN, FENGJIE; YANG, XUEQIN; ZHANG, SHENGLI

    2012-01-01

    Radiation lung injury is a common side-effect of pulmonary radiotherapy. The aim of this study was to quantitatively assess early changes in lung perfusion single photon emission computed tomography (SPECT) scanning and pulmonary function testing (PFT) prior to and after intensity modulated radiotherapy (IMRT) for patients suffering from locally advanced non-small cell lung cancer (LANSCLC). Twenty patients with LANSCLC received lung perfusion SPECT scanning and PFT prior to IMRT and immediately after IMRT. Lung perfusion index (LPI) was calculated after the quantification of perfusion SPECT images. The LPI of the two groups was analyzed by matched t-test. The radioactive count of each layer of single lung was added to obtain the sum of the irradiated area. The percentage of the irradiated area of single lung was calculated. Linear correlation analysis was carried out between the percentage of the irradiated area and LPI in order to verify the validity of LPI. In this study, LPI and the percentage of the irradiated area of single lung exhibited an excellent correlation either prior to or after IMRT (r=0.820 and r=0.823, respectively; p<0.001). There was no statistically significant difference between pre-IMRT LPI and post-IMRT LPI (p=0.135). LPI in the group receiving a radical dose had no statistically significant difference (p=0.993), however, it showed a statistically significant difference in the group receiving a non-radical dose (p=0.025). In the non-radical dose group, the post-IMRT LPI was larger compared to pre-IMRT. None of the parameters of PFT exhibited a statistically significant difference prior to and after IMRT (p>0.05). The quantitative method of lung perfusion SPECT scanning can be used to evaluate changes in perfusion early in patients receiving a non-radical dose (BED ≤126,500 cGy) IMRT. Evaluating early changes in global lung function using the current method of PFT is difficult, since time can be a contributing factor for radiation

  13. Ex-vivo lung perfusion.

    PubMed

    Van Raemdonck, Dirk; Neyrinck, Arne; Cypel, Marcelo; Keshavjee, Shaf

    2015-06-01

    This review outlines the new and promising technique of ex vivo lung perfusion and its clinical potential to increase the number of transplantable lungs and to improve the early and late outcome after transplantation. The rationale, the experimental background, the technique and protocols, and available devices for ex vivo lung perfusion are discussed. The current clinical experience worldwide and ongoing clinical trials are reviewed.

  14. Ex-vivo lung perfusion.

    PubMed

    Van Raemdonck, Dirk; Neyrinck, Arne; Cypel, Marcelo; Keshavjee, Shaf

    2015-06-01

    This review outlines the new and promising technique of ex vivo lung perfusion and its clinical potential to increase the number of transplantable lungs and to improve the early and late outcome after transplantation. The rationale, the experimental background, the technique and protocols, and available devices for ex vivo lung perfusion are discussed. The current clinical experience worldwide and ongoing clinical trials are reviewed. PMID:24629039

  15. A novel application of microsphere perfusion and scanning electron microscopy to the identification of pulmonary arterioles in guinea-pig and rabbit lungs.

    PubMed

    Walker, D C; Hosford, S; Mackenzie, A

    1994-05-01

    In arterioles of the lung the intravascular blood pressures are lower than in comparable vessels in the systemic circulation and the arteriole walls are thinner. Therefore, it is very difficult to distinguish between arterioles and venules of the same size using scanning electron microscopy. This study describes a novel application of latex microsphere perfusion and scanning electron microscopy which distinguishes between pulmonary arterioles and venules on the basis of endothelial cell morphology. Microspheres, 90 and 45 microns in diameter, were perfused into the arterial side of the pulmonary circulation of guinea-pig and rabbit lungs. Scanning electron microscopy of the arterioles on both sides of the lodged microspheres indicated that the endothelial cells are spindle shaped. In contrast, the endothelial cells of equal diameter venules are polygonal. Furthermore, the nuclei of the arteriolar endothelial cells were significantly (P = 0.019) narrower than those of endothelial cells in venules of equal diameter. Finally, it was observed that the differences between arteriole and venule endothelial cells persisted distally to the capillaries.

  16. Ex vivo lung perfusion and reconditioning.

    PubMed

    Yeung, Jonathan C; Cypel, Marcelo; Massad, Ehab; Keshavjee, Shaf

    2011-01-01

    Normothermic ex vivo lung perfusion can act as a platform for the evaluation and repair of donor lungs. An acellular hyperosmolar solution is perfused anterograde through the donor lungs at 40% of the estimated cardiac output. Following oxygenation of the perfusate by the lung, it passes through a hollow fiber oxygenator supplied with a hypoxic gas mixture to remove oxygen and to maintain physiological carbon dioxide levels. Flow through a heat exchanger to maintain normothermia and a leukocyte filter to remove demarginated leukocytes completes the circuit. Lung function can be measured by the difference in PO2 between the perfusate postlung and postmembrane and by physiological parameters. Utilization of this method of ex vivo donor lung evaluation should reduce concerns of primary graft dysfunction and increase utilization rates of donor lungs. PMID:24412979

  17. Novel Technologies for Isolated Lung Perfusion: Beyond Lung Transplant.

    PubMed

    Cypel, Marcelo; Keshavjee, Shaf

    2016-05-01

    Isolated lung perfusion (ILP) has been examined and developed in lung transplantation and thoracic oncology research. In lung transplantation, ILP has been used to assess physiologic integrity of donor lungs after removal from the donor, and it has also been proposed as a method for active treatment and repair of injured unsuitable donor organs ex vivo. ILP is attractive as a concept to deliver high-dose chemotherapy to treat pulmonary metastatic disease, referred to as in vivo lung perfusion. This article focuses on the rationale, technical aspects, and experimental and clinical experience of in vivo lung perfusion. A perspective on the future application of these techniques is described. PMID:27112253

  18. Novel method of lung area extraction in chest perfusion computed tomography.

    PubMed

    Kalicka, Renata; Lipiński, Seweryn; Browarczyk, Maciej

    2013-02-01

    Chest perfusion computed tomography (pCT) is a useful technique in the medical diagnosis of how organs function. Perfusion CT scans are used to calculate perfusion parameters. In the case of automated methods of lung perfusion parameters calculation, the prior extraction of the lung area is desired to avoid unnecessary calculation in an area outside the lung cross-section and to avoid wasting time on processing signals of no diagnostic importance. Our new method is designed to extract a lung cross-section from a whole series of chest pCT images. It uses a complete sequence of pCT scans to extract the rough lung contour. Next each scan is processed individually, within the rough contour, to obtain a detailed, individual outline of the lungs. The proposed method and obtained results are presented and compared with methods known in literature.

  19. Regional pulmonary perfusion following human heart-lung transplantation

    SciTech Connect

    Lisbona, R.; Hakim, T.S.; Dean, G.W.; Langleben, D.; Guerraty, A.; Levy, R.D. )

    1989-08-01

    Ventilation and perfusion scans were obtained in six subjects who had undergone heart-lung transplantation with consequent denervation of the cardiopulmonary axis. Two of the subjects had developed obliterative bronchiolitis, which is believed to be a form of chronic rejection. Their pulmonary function tests demonstrated airflow obstruction and their scintigraphic studies were abnormal. In the remaining four subjects without obstructive airways disease, ventilation and planar perfusion scans were normal. Single photon emission computed tomography imaging of pulmonary perfusion in these patients revealed a layered distribution of blood flow indistinguishable from that of normal individuals. It is concluded that neurogenic mechanisms have little influence on the pattern of local pulmonary blood flow at rest.

  20. Ex vivo lung perfusion in Brazil

    PubMed Central

    Abdalla, Luis Gustavo; Braga, Karina Andrighetti de Oliveira; Nepomuceno, Natalia Aparecida; Fernandes, Lucas Matos; Samano, Marcos Naoyuki; Pêgo-Fernandes, Paulo Manuel

    2016-01-01

    Objective: To evaluate the use of ex vivo lung perfusion (EVLP) clinically to prepare donor lungs for transplantation. Methods: A prospective study involving EVLP for the reconditioning of extended-criteria donor lungs, the criteria for which include aspects such as a PaO2/FiO2 ratio < 300 mmHg. Between February of 2013 and February of 2014, the lungs of five donors were submitted to EVLP for up to 4 h each. During EVLP, respiratory mechanics were continuously evaluated. Once every hour during the procedure, samples of the perfusate were collected and the function of the lungs was evaluated. Results: The mean PaO2 of the recovered lungs was 262.9 ± 119.7 mmHg at baseline, compared with 357.0 ± 108.5 mmHg after 3 h of EVLP. The mean oxygenation capacity of the lungs improved slightly over the first 3 h of EVLP-246.1 ± 35.1, 257.9 ± 48.9, and 288.8 ± 120.5 mmHg after 1, 2, and 3 h, respectively-without significant differences among the time points (p = 0.508). The mean static compliance was 63.0 ± 18.7 mmHg, 75.6 ± 25.4 mmHg, and 70.4 ± 28.0 mmHg after 1, 2, and 3 h, respectively, with a significant improvement from hour 1 to hour 2 (p = 0.029) but not from hour 2 to hour 3 (p = 0.059). Pulmonary vascular resistance remained stable during EVLP, with no differences among time points (p = 0.284). Conclusions: Although the lungs evaluated remained under physiological conditions, the EVLP protocol did not effectively improve lung function, thus precluding transplantation. PMID:27167429

  1. Lung gallium scan

    MedlinePlus

    ... inflammation in the lungs, most often due to sarcoidosis or a certain type of pneumonia. Normal Results ... up very little gallium. What Abnormal Results Mean Sarcoidosis Other respiratory infections, most often pneumocystis jirovecii pneumonia ...

  2. Positron emission tomography to assess hypoxia and perfusion in lung cancer

    PubMed Central

    Verwer, Eline E; Boellaard, Ronald; van der Veldt, Astrid AM

    2014-01-01

    In lung cancer, tumor hypoxia is a characteristic feature, which is associated with a poor prognosis and resistance to both radiation therapy and chemotherapy. As the development of tumor hypoxia is associated with decreased perfusion, perfusion measurements provide more insight into the relation between hypoxia and perfusion in malignant tumors. Positron emission tomography (PET) is a highly sensitive nuclear imaging technique that is suited for non-invasive in vivo monitoring of dynamic processes including hypoxia and its associated parameter perfusion. The PET technique enables quantitative assessment of hypoxia and perfusion in tumors. To this end, consecutive PET scans can be performed in one scan session. Using different hypoxia tracers, PET imaging may provide insight into the prognostic significance of hypoxia and perfusion in lung cancer. In addition, PET studies may play an important role in various stages of personalized medicine, as these may help to select patients for specific treatments including radiation therapy, hypoxia modifying therapies, and antiangiogenic strategies. In addition, specific PET tracers can be applied for monitoring therapy. The present review provides an overview of the clinical applications of PET to measure hypoxia and perfusion in lung cancer. Available PET tracers and their characteristics as well as the applications of combined hypoxia and perfusion PET imaging are discussed. PMID:25493221

  3. Scintigraphic perfusion patterns in patients with diffuse lung disease

    SciTech Connect

    Newman, G.E.; Sullivan, D.C.; Gottschalk, A.; Putman, C.E.

    1982-04-01

    Perfusion scintigrams of 55 patients with radiographic evidence of diffuse lung disease were reviewed. Thirty-nine had acute and/or chronic changes caused by congestive heart failure, and 16 had diffuse reticulonodular disease. A normal or near-normal perfusion pattern was seen in 40/55 (73%), and this finding was equally common in the two groups. The authors conclude that perfusion scintigraphy is useful in excluding pulmonary embolism in patients with radiographic evidence of diffuse, symmetrical lung disease.

  4. Prediction of postoperative pulmonary function following thoracic operations. Value of ventilation-perfusion scanning

    SciTech Connect

    Bria, W.F.; Kanarek, D.J.; Kazemi, H.

    1983-08-01

    Surgical resection of lung cancer is frequently required in patients with severely impaired lung function resulting from chronic obstructive pulmonary disease. Twenty patients with obstructive lung disease and cancer (mean preoperative forced expiratory volume in 1 second (FEV1) . 1.73 L) were studied preoperatively and postoperatively by spirometry and radionuclide perfusion, single-breath ventilation, and washout techniques to test the ability of these methods to predict preoperatively the partial loss of lung function by the resection. Postoperative FEV1 and forced vital capacity (FVC) were accurately predicted by the formula: postoperative FEV1 (or FVC) . preoperative FEV1 X percent function of regions of lung not to be resected (r . 0.88 and 0.95, respectively). Ventilation and perfusion scans are equally effective in prediction. Washout data add to the sophistication of the method by permitting the qualitative evaluation of ventilation during tidal breathing. Criteria for patients requiring the study are suggested.

  5. Tc-99m MAA lung perfusion scintigraphy performed before and after pulmonary embolectomy for saddle-type pulmonary embolism.

    PubMed

    Shih, W J; Robinson, M C; Huber, C; Pulmano, C

    1995-02-01

    A 58-year-old man had shortness of breath, hypotension, and decreased partial pressure of oxygen (PO2) on the eighteenth day after undergoing craniotomy for a meningioma. Tc-99m MAA pulmonary perfusion scintigraphy showed little perfusion to the right lung and left lower lung and multiple perfusion defects in the left upper lung. Although the results of concurrent chest radiography were negative for pulmonary infiltrates, pulmonary angiography demonstrated a saddle-type embolism. The patient underwent emergency pulmonary artery embolectomy to remove blood clots and organized thromboemboli from the main pulmonary artery and the right and left pulmonary arteries. The patient's postoperative course was uneventful, and a second Tc-99m MAA lung perfusion scan demonstrated marked improvement in lung perfusion.

  6. Perfusion Scintigraphy and Patient Selection for Lung Volume Reduction Surgery

    PubMed Central

    Chandra, Divay; Lipson, David A.; Hoffman, Eric A.; Hansen-Flaschen, John; Sciurba, Frank C.; DeCamp, Malcolm M.; Reilly, John J.; Washko, George R.

    2010-01-01

    Rationale: It is unclear if lung perfusion can predict response to lung volume reduction surgery (LVRS). Objectives: To study the role of perfusion scintigraphy in patient selection for LVRS. Methods: We performed an intention-to-treat analysis of 1,045 of 1,218 patients enrolled in the National Emphysema Treatment Trial who were non–high risk for LVRS and had complete perfusion scintigraphy results at baseline. The median follow-up was 6.0 years. Patients were classified as having upper or non–upper lobe–predominant emphysema on visual examination of the chest computed tomography and high or low exercise capacity on cardiopulmonary exercise testing at baseline. Low upper zone perfusion was defined as less than 20% of total lung perfusion distributed to the upper third of both lungs as measured on perfusion scintigraphy. Measurements and Main Results: Among 284 of 1,045 patients with upper lobe–predominant emphysema and low exercise capacity at baseline, the 202 with low upper zone perfusion had lower mortality with LVRS versus medical management (risk ratio [RR], 0.56; P = 0.008) unlike the remaining 82 with high perfusion where mortality was unchanged (RR, 0.97; P = 0.62). Similarly, among 404 of 1,045 patients with upper lobe–predominant emphysema and high exercise capacity, the 278 with low upper zone perfusion had lower mortality with LVRS (RR, 0.70; P = 0.02) unlike the remaining 126 with high perfusion (RR, 1.05; P = 1.00). Among the 357 patients with non–upper lobe–predominant emphysema (75 with low and 282 with high exercise capacity) there was no improvement in survival with LVRS and measurement of upper zone perfusion did not contribute new prognostic information. Conclusions: Compared with optimal medical management, LVRS reduces mortality in patients with upper lobe–predominant emphysema when there is low rather than high perfusion to the upper lung. PMID:20538961

  7. Perfusion of nonventilated lung: failure of hypoxic vasoconstriction

    SciTech Connect

    Sostman, H.D.; Neumann, R.D.; Gottschalk, A.; Greenspan, R.H.

    1983-07-01

    Alveolar hypoxia is a well established cause of regional vasoconstriction such that nonventilated segments are not perfused. The paradoxical situation of retained perfusion of nonventilated lung has seldom been discussed. Three clinical examples are illustrated. In each case coexistent chronic obstructive lung disease may have contributed to this unexpected finding by reducing pulmonary vascular capacity such that blood flow diversion from hypoxic segments was not possible.

  8. Logistic ex Vivo Lung Perfusion for Hyperimmunized Patients.

    PubMed

    De Wolf, Julien; Puyo, Philippe; Bonnette, Pierre; Roux, Antoine; Le Guen, Morgan; Parquin, François; Chapelier, Alain; Sage, Edouard

    2016-09-01

    Hyperimmunized patients have restricted access to lung transplantation because of the low rate of donor lung availability. Sensitization to human leukocyte antigen is associated with acute rejection, allograft dysfunction, and decreased survival. Prospective crossmatching could allow matching a lung graft with the recipient; however, such a strategy would increase graft ischemia, with a worse impact on the long-term results of lung transplantation. We used logistic ex vivo lung perfusion for 3 patients at the Foch Hospital while waiting for a negative result of the prospective crossmatching and then moved forward to lung transplantation. All patients are alive 3 years after bilateral lung transplantation.

  9. Logistic ex Vivo Lung Perfusion for Hyperimmunized Patients.

    PubMed

    De Wolf, Julien; Puyo, Philippe; Bonnette, Pierre; Roux, Antoine; Le Guen, Morgan; Parquin, François; Chapelier, Alain; Sage, Edouard

    2016-09-01

    Hyperimmunized patients have restricted access to lung transplantation because of the low rate of donor lung availability. Sensitization to human leukocyte antigen is associated with acute rejection, allograft dysfunction, and decreased survival. Prospective crossmatching could allow matching a lung graft with the recipient; however, such a strategy would increase graft ischemia, with a worse impact on the long-term results of lung transplantation. We used logistic ex vivo lung perfusion for 3 patients at the Foch Hospital while waiting for a negative result of the prospective crossmatching and then moved forward to lung transplantation. All patients are alive 3 years after bilateral lung transplantation. PMID:27549543

  10. Perfusion-related stimuli for compensatory lung growth following pneumonectomy.

    PubMed

    Dane, D Merrill; Yilmaz, Cuneyt; Gyawali, Dipendra; Iyer, Roshni; Ravikumar, Priya; Estrera, Aaron S; Hsia, Connie C W

    2016-07-01

    Following pneumonectomy (PNX), two separate mechanical forces act on the remaining lung: parenchymal stress caused by lung expansion, and microvascular distension and shear caused by increased perfusion. We previously showed that parenchymal stress and strain explain approximately one-half of overall compensation; the remainder was presumptively attributed to perfusion-related factors. In this study, we directly tested the hypothesis that perturbation of regional pulmonary perfusion modulates post-PNX lung growth. Adult canines underwent banding of the pulmonary artery (PAB) to the left caudal (LCa) lobe, which caused a reduction in basal perfusion to LCa lobe without preventing the subsequent increase in its perfusion following right PNX while simultaneously exaggerating the post-PNX increase in perfusion to the unbanded lobes, thereby creating differential perfusion changes between banded and unbanded lobes. Control animals underwent sham pulmonary artery banding followed by right PNX. Pulmonary function, regional pulmonary perfusion, and high-resolution computed tomography of the chest were analyzed pre-PNX and 3-mo post-PNX. Terminally, the remaining lobes were fixed for detailed morphometric analysis. Results were compared with corresponding lobes in two control (Sham banding and normal unoperated) groups. PAB impaired the indices of post-PNX extravascular alveolar tissue growth by up to 50% in all remaining lobes. PAB enhanced the expected post-PNX increase in alveolar capillary formation, measured by the prevalence of double-capillary profiles, in both unbanded and banded lobes. We conclude that perfusion distribution provides major stimuli for post-PNX compensatory lung growth independent of the stimuli provided by lung expansion and parenchymal stress and strain.

  11. Ex Vivo Perfusion Treatment of Infection in Human Donor Lungs.

    PubMed

    Nakajima, D; Cypel, M; Bonato, R; Machuca, T N; Iskender, I; Hashimoto, K; Linacre, V; Chen, M; Coutinho, R; Azad, S; Martinu, T; Waddell, T K; Hwang, D M; Husain, S; Liu, M; Keshavjee, S

    2016-04-01

    Ex vivo lung perfusion (EVLP) is a platform to treat infected donor lungs with antibiotic therapy before lung transplantation. Human donor lungs that were rejected for transplantation because of clinical concern regarding infection were randomly assigned to two groups. In the antibiotic group (n = 8), lungs underwent EVLP for 12 h with high-dose antibiotics (ciprofloxacin 400 mg or azithromycin 500 mg, vancomycin 15 mg/kg, and meropenem 2 g). In the control group (n = 7), lungs underwent EVLP for 12 h without antibiotics. A quantitative decrease in bacterial counts in bronchoalveolar lavage (BAL) was found in all antibiotic-treated cases but in only two control cases. Perfusate endotoxin levels at 12 h were significantly lower in the antibiotic group compared with the control group. EVLP with broad-spectrum antibiotic therapy significantly improved pulmonary oxygenation and compliance and reduced pulmonary vascular resistance. Perfusate endotoxin levels at 12 h were strongly correlated with levels of perfusates tumor necrosis factor α, IL-1β and macrophage inflammatory proteins 1α and 1β at 12 h. In conclusion, EVLP treatment of infected donor lungs with broad-spectrum antibiotics significantly reduced BAL bacterial counts and endotoxin levels and improved donor lung function. PMID:26730551

  12. Evaluation of pulmonary perfusion in lung regions showing isolated xenon-133 ventilation washout defects

    SciTech Connect

    Bushnell, D.L.; Sood, K.B.; Shirazi, P.; Pal, I. )

    1990-08-01

    Xenon-133 washout phase imaging is often used to help determine whether the etiology of a perfusion defect is embolic or due to pulmonary parenchymal pathology, such as chronic obstructive pulmonary disease. This study was designed to evaluate the pulmonary blood flow patterns associated with isolated defects on xenon washout images. Scintigraphic lung studies were reviewed until 100 cases with abnormal ventilation results were obtained. Ventilation abnormalities were compared with the corresponding perfusion scan results at the same anatomic site. Of the 208 individual lung regions with xenon abnormalities, 111 showed isolated washout defects (that is, with normal washin). Ninety-four of these 111 sites showed either normal perfusion or a small, nonsegmental corresponding perfusion defect. Three segmental perfusion defects were noted in association with isolated xenon retention. In each of these cases, however, the patient was felt actually to have pulmonary embolism. Thus, it is recommended that, for interpretation of scintigraphic images in the assessment of pulmonary embolism, lung pathology associated with isolated xenon retention not be considered a potential cause for large or segmental perfusion defects.

  13. Review of diagnostic uses of shunt fraction quantification with technetium-99m macroaggregated albumin perfusion scan as illustrated by a case of Osler-Weber-Rendu syndrome.

    PubMed

    Chokkappan, Kabilan; Kannivelu, Anbalagan; Srinivasan, Sivasubramanian; Babut, Suresh Balasubramanian

    2016-01-01

    Bilateral pulmonary arteriovenous malformations (AVMs) are rare and are often associated with the hereditary hemorrhagic telangiectasia (HHT/Osler-Weber-Rendu) syndrome. We present a woman who presented with neurological symptoms due to a cerebral abscess. On further evaluation, bilateral pulmonary AVMs were identified. The patient was diagnosed with HHT, based on positive family history and multiple cerebral AVMs recognized on subsequent catheter angiogram, in addition to the presence of bilateral pulmonary AVMs. Craniotomy with drainage of the brain abscess and endovascular embolization of the pulmonary AVMs was offered to the patient. As a preembolization work-up, the patient underwent nuclear lung perfusion scan with technetium-99m macroaggregated albumin (Tc-99m MAA) to assess the right-to-left shunt secondary to the pulmonary AVMs. Postembolization follow-up perfusion scan was also obtained to estimate the hemodynamic response. The case is presented to describe the role of Tc-99m MAA perfusion lung scan in preoperatively evaluating patients with pulmonary AVMs and to emphasize on the scan's utility in posttreatment follow-up. Various present day usages of the Tc-99m MAA lung perfusion scan, other than diagnosing pulmonary thromboembolism, are discussed. Providing background knowledge on the physiological and hemodynamic aspects of the Tc-99m MAA lung perfusion scan is also attempted. Various imaging pitfalls and necessary precautions while performing Tc-99m MAA lung perfusion scan are highlighted.

  14. Human Lung Cancer Cells Grown on Acellular Rat Lung Matrix Create Perfusable Tumor Nodules

    PubMed Central

    Mishra, Dhruva K.; Thrall, Michael J.; Baird, Brandi N.; Ott, Harald C.; Blackmon, Shanda H.; Kurie, Jonathan M.; Kim, Min P.

    2015-01-01

    Background Extracellular matrix allows lung cancer to form its shape and grow. Recent studies on organ reengineering for orthotopic transplantation have provided a new avenue for isolating purified native matrix to use for growing cells. Whether human lung cancer cells grown in a decellularized rat lung matrix would create perfusable human lung cancer nodules was tested. Methods Rat lungs were harvested and native cells were removed using sodium dodecyl sulfate and Triton X-100 in a decellularization chamber to create a decellularized rat lung matrix. Human A549, H460, or H1299 lung cancer cells were placed into the decellularized rat lung matrix and grown in a customized bioreactor with perfusion of oxygenated media for 7 to 14 days. Results Decellularized rat lung matrix showed preservation of matrix architecture devoid of all rat cells. All three human lung cancer cell lines grown in the bioreactor developed tumor nodules with intact vasculature. Moreover, the lung cancer cells developed a pattern of growth similar to the original human lung cancer. Conclusions Overall, this study shows that human lung cancer cells form perfusable tumor nodules in a customized bioreactor on a decellularized rat lung matrix created by a customized decellularization chamber. The lung cancer cells grown in the matrix had features similar to the original human lung cancer. This ex vivo model can be used potentially to gain a deeper understanding of the biologic processes involved in human lung cancer. PMID:22385822

  15. Prilocaine elimination by isolated perfused rat lung and liver.

    PubMed

    Geng, W P; Ebke, M; Foth, H

    1995-01-01

    Prilocaine is assumed to undergo significant elimination by extrahepatic organs and to differ in this respect from other commonly used local anaesthetics. In order to clarify whether the lung may play an important role as a site of elimination of prilocaine, the kinetic parameters were studied in isolated perfused rat lungs and were compared to those of isolated livers. Furthermore, the structurally related compounds bupivacaine and mepivacaine were also investigated in this system. Prilocaine was dispersed into a relatively large apparent distribution volume in perfused rat lung (139 ml versus 97 ml in controls). In single-pass perfused lungs the observed maximum of concentration was decreased by about 60% compared to controls. The mean residence time was prolonged by about 40%. These observations suggest that prilocaine is substantially retained by rat lung and that this effect occurs particularly during first-pass. However, the ability of rat lung to degrade prilocaine was relatively low. The clearance values were about 0.3 ml/min equal to about 20% of the hepatic capacity calculated per g of tissue. Thus it must be assumed that prilocaine is only transiently retained by the lung and will gain systemic availability later on. In rat lungs the kinetics of prilocaine elimination were not substantially different from those of bupivacaine and mepivacaine (16 and 12%). These observations do not support the assumption that especially prilocaine undergoes extrahepatic elimination.

  16. Regional lung perfusion estimated by electrical impedance tomography in a piglet model of lung collapse.

    PubMed

    Borges, João Batista; Suarez-Sipmann, Fernando; Bohm, Stephan H; Tusman, Gerardo; Melo, Alexandre; Maripuu, Enn; Sandström, Mattias; Park, Marcelo; Costa, Eduardo L V; Hedenstierna, Göran; Amato, Marcelo

    2012-01-01

    The assessment of the regional match between alveolar ventilation and perfusion in critically ill patients requires simultaneous measurements of both parameters. Ideally, assessment of lung perfusion should be performed in real-time with an imaging technology that provides, through fast acquisition of sequential images, information about the regional dynamics or regional kinetics of an appropriate tracer. We present a novel electrical impedance tomography (EIT)-based method that quantitatively estimates regional lung perfusion based on first-pass kinetics of a bolus of hypertonic saline contrast. Pulmonary blood flow was measured in six piglets during control and unilateral or bilateral lung collapse conditions. The first-pass kinetics method showed good agreement with the estimates obtained by single-photon-emission computerized tomography (SPECT). The mean difference (SPECT minus EIT) between fractional blood flow to lung areas suffering atelectasis was -0.6%, with a SD of 2.9%. This method outperformed the estimates of lung perfusion based on impedance pulsatility. In conclusion, we describe a novel method based on EIT for estimating regional lung perfusion at the bedside. In both healthy and injured lung conditions, the distribution of pulmonary blood flow as assessed by EIT agreed well with the one obtained by SPECT. The method proposed in this study has the potential to contribute to a better understanding of the behavior of regional perfusion under different lung and therapeutic conditions.

  17. Ventilation/perfusion scan and dead space in pulmonary embolism: are they useful for the diagnosis?

    PubMed

    Giuntini, C

    2001-12-01

    The diagnostic strategy for pulmonary embolism, based on the mismatch of the ventilation/perfusion scan, was developed some 30 years ago on the following assumption: since the disorder involves the pulmonary vessels, it was surmised that in the embolized regions lung alveoli are unperfused or poorly perfused but well ventilated. Hence, it was inferred that this disorder was characterized, unlike parenchymal disease, by ventilation/perfusion mismatch in the affected lung zones and by an obvious increase of wasted ventilation, i.e., dead space. As matter of fact, experimental evidence on the redistribution of ventilation away from the vascular occluded lung had been already obtained in the early 60s of the last century. More recently, the behavior of regional pulmonary ventilation (V(A)) and blood flow (Q) in patients with acute pulmonary embolism (APE) has been studied by applying the multiple inert gas elimination technique (MIGET). It has been shown that the development of lung units with high V(A)/Q ratio (those with relative prevalence of perfusion obstruction) is accompanied by substantial redistribution of ventilation away from these units. Furthermore, radioisotopic techniques, used to visualize the topographic distributions of V(A) and Q in the same patients studied by MIGET, have shown reduced or absent V(A) in the embolized regions. This may occur by different mechanisms in the various stages of APE: bronchoconstriction mediated by local hypocapnia, atelectasis (occasionally hemorrhagic) related to alteration of surfactant production, bronchiolar obstruction and pulmonary infarction ascribed to degenerative and/or necrotic changes secondary to insufficient blood flow. In dogs and humans alike, the dead space measured by MIGET does not increase and that obtained from CO2 increases far less than the amount of unperfused lung in APE thus confirming a substantial redistribution of ventilation away from the embolized lung zones. Taken together, all these

  18. Radiation-Induced Reductions in Regional Lung Perfusion: 0.1-12 Year Data From a Prospective Clinical Study

    SciTech Connect

    Zhang Junan; Ma Jinli; Zhou Sumin; Hubbs, Jessica L.; Wong, Terence Z.; Folz, Rodney J.; Evans, Elizabeth S.; Jaszczak, Ronald J.; Clough, Robert; Marks, Lawrence B.

    2010-02-01

    Purpose: To assess the time and regional dependence of radiation therapy (RT)-induced reductions in regional lung perfusion 0.1-12 years post-RT, as measured by single photon emission computed tomography (SPECT) lung perfusion. Materials/Methods: Between 1991 and 2005, 123 evaluable patients receiving RT for tumors in/around the thorax underwent SPECT lung perfusion scans before and serially post-RT (0.1-12 years). Registration of pre- and post-RT SPECT images with the treatment planning computed tomography, and hence the three-dimensional RT dose distribution, allowed changes in regional SPECT-defined perfusion to be related to regional RT dose. Post-RT follow-up scans were evaluated at multiple time points to determine the time course of RT-induced regional perfusion changes. Population dose response curves (DRC) for all patients at different time points, different regions, and subvolumes (e.g., whole lungs, cranial/caudal, ipsilateral/contralateral) were generated by combining data from multiple patients at similar follow-up times. Each DRC was fit to a linear model, and differences statistically analyzed. Results: In the overall groups, dose-dependent reductions in perfusion were seen at each time post-RT. The slope of the DRC increased over time up to 18 months post-RT, and plateaued thereafter. Regional differences in DRCs were only observed between the ipsilateral and contralateral lungs, and appeared due to tumor-associated changes in regional perfusion. Conclusions: Thoracic RT causes dose-dependent reductions in regional lung perfusion that progress up to {approx}18 months post-RT and persists thereafter. Tumor shrinkage appears to confound the observed dose-response relations. There appears to be similar dose response for healthy parts of the lungs at different locations.

  19. The clinical potential of ex vivo lung perfusion.

    PubMed

    Cypel, Marcelo; Keshavjee, Shaf

    2012-02-01

    The number of patients listed for lung transplantation largely exceeds the number of available transplantable organs because of both a shortage of organ donors and a low utilization rate of donor lungs. Normothermic ex vivo lung perfusion (EVLP) is a method that maintains the organ in physiologically protective conditions outside the body during preservation, and shows great promise to increase utilization of donor lungs by allowing more accurate evaluation, as well as treatment and repair, of damaged donor lungs prior to transplantation. This article will cover the rationale, technical details and results of experimental and clinical studies with EVLP. The significant potential applications of EVLP in lung transplantation, lung regeneration and oncology are discussed. PMID:22283576

  20. Patterns of pulmonary perfusion scans in normal subjects

    SciTech Connect

    Wallace, J.M.; Moser, K.M.; Hartman, M.T.; Ashburn, W.L.

    1981-01-01

    A vital factor conditioning the usage of the pulmonary perfusion (Q) scan in the evaluation of patients suspected of pulmonary embolism is the prevalence of abnormal Q scans in subjects free of cardiopulmonary disease. Because this prevalence has not been well defined, we performed Q scans in 80 nonsmoking subjects 18 to 29 yr of age having no known active cardiopulmonary disease. Each subject underwent a history, physical examination, electrocardiogram, spirometry, and PA chest roentgenogram, followed by a 6-view Q scan. Two subjects in whom a Q defect was suspected underwent a /sup 133/Xe equilibrium-washout ventilation (V) scan. All Q scans were interpreted blindly and independently by 2 experienced readers. Seventy-nine of the 80 Q scans were read as normal. No subject demonstrated a lobar or segmental defect. One of the 80 subjects, who had a mild pectus excavatum, had a left upper lobe subsegmental defect, which was not seen on the V scan. Based on the statistical analysis of these data, no more than 3.68% of normal nonsmoking persons in this age group may have a lobar or segmental Q scan defect and no more than 6.77% may have a subsegmental defect (with 95% confidence). Therefore, our study indicated that Q scan defects, particularly lobar or segmental, are rarely present among normal nonsmokers in this age group.

  1. Degradation of bradykinin by isolated perfused rat lung

    SciTech Connect

    Churchill, M.; Orawski, A.T.; AchutaMurthy, P.N.; Simmons, W.H.

    1986-03-01

    Several studies have suggested that the essentially complete degradation of circulating bradykinin (BK) in lung is mediated in part by peptidase(s) other than the well-characterized angiotensin converting enzyme (ACE). The authors report here that the isolated perfused rat lung can inactivate BK by sequential N-terminal cleavage. (/sup 3/H-2, 3-Pro) BK was perfused through the lung and the products in the perfusate identified by HPLC. In the absence of inhibitors, BK was 89-100% degraded with /sup 3/H-Pro/sup 2/-Pro/sup 3/ and /sup 3/H-Pro as the major products. The dipeptidylaminopeptidase IV (DAP IV) inhibitor, diprotein A (Ile-Pro-Ile), greatly reduced the Pro-Pro and Pro peaks and produced a prominent BK/sub 2-7/ peak (or BK/sub 2-9/ peak if the ACE inhibitor, captopril, was also present). 2-Mercapto-ethanol, a rather specific inhibitor of aminopeptidase P (AP-P), prevented the release of Arg/sup 1/, producing major BK and/or BK/sub 1-7/ peaks. The neutral metalloendopeptidase inhibitor, phosphoramidon, had no effect on the pattern of degradation of BK by the perfused rat lung by the release of Arg/sup 1/ by AP-P followed by release of Pro/sup 2/-Pro/sup 3/ by DAP IV.

  2. A novel dual ex vivo lung perfusion technique improves immediate outcomes in an experimental model of lung transplantation.

    PubMed

    Tanaka, Y; Noda, K; Isse, K; Tobita, K; Maniwa, Y; Bhama, J K; D'Cunha, J; Bermudez, C A; Luketich, J D; Shigemura, N

    2015-05-01

    The lungs are dually perfused by the pulmonary artery and the bronchial arteries. This study aimed to test the feasibility of dual-perfusion techniques with the bronchial artery circulation and pulmonary artery circulation synchronously perfused using ex vivo lung perfusion (EVLP) and evaluate the effects of dual-perfusion on posttransplant lung graft function. Using rat heart-lung blocks, we developed a dual-perfusion EVLP circuit (dual-EVLP), and compared cellular metabolism, expression of inflammatory mediators, and posttransplant graft function in lung allografts maintained with dual-EVLP, standard-EVLP, or cold static preservation. The microvasculature in lung grafts after transplant was objectively evaluated using microcomputed tomography angiography. Lung grafts subjected to dual-EVLP exhibited significantly better lung graft function with reduced proinflammatory profiles and more mitochondrial biogenesis, leading to better posttransplant function and compliance, as compared with standard-EVLP or static cold preservation. Interestingly, lung grafts maintained on dual-EVLP exhibited remarkably increased microvasculature and perfusion as compared with lungs maintained on standard-EVLP. Our results suggest that lung grafts can be perfused and preserved using dual-perfusion EVLP techniques that contribute to better graft function by reducing proinflammatory profiles and activating mitochondrial respiration. Dual-EVLP also yields better posttransplant graft function through increased microvasculature and better perfusion of the lung grafts after transplantation.

  3. Isolated perfused lung preparation for studying altered gaseous environments.

    PubMed Central

    Rhoades, R A

    1984-01-01

    The isolated perfused lung (IPL) preparation is ideally suited to investigate lung dynamics and cellular function, and is easily adapted to investigating biochemical and physiological responses to environmental insults. The IPL offers several advantages which permit one to study endothelial/epithelial interactions that are often disrupted with other model systems (e.g., isolated cells, minces, slices, homogenates, etc.). The IPL developed in our laboratory was devised for the rat lung and allows four lungs to be perfused simultaneously in which control over ventilation, flow, pressure, pH, PO2 and PCO2 can be maintained. Isolated lungs perfused for 1 to 2 hr at a flow rate of 10 mL/min exhibit less that 2% weight gain, maintain normal ATP levels, and exhibit linear substrate uptake. Mechanisms leading to changes in vascular and airway resistance, lipid metabolism, vasoactive hormones, blood gases and changes in vascular permeability mediated by environmental insults can be quantified in the IPL preparation. PMID:6383801

  4. Effective avoidance of a functional spect-perfused lung using intensity modulated radiotherapy (IMRT) for non-small cell lung cancer (NSCLC): an update of a planning study.

    PubMed

    Lavrenkov, Konstantin; Singh, Shalini; Christian, Judith A; Partridge, Mike; Nioutsikou, Elena; Cook, Gary; Bedford, James L; Brada, Michael

    2009-06-01

    IMRT and 3-dimensional conformal radiotherapy (3-DCRT) plans of 25 patients with non-small cell lung (NSCLC) were compared in terms of planning target volume (PTV) coverage and sparing of functional lung (FL) defined by a SPECT perfusion scan. IMRT resulted in significant reduction of functional V(20) and mean lung dose in stage III patients with inhomogeneous hypoperfusion. If the dose to FL is shown to be the determinant of lung toxicity, IMRT would allow for effective dose escalation by specific avoidance of functional lung. PMID:18995919

  5. Ex Vivo Lung Perfusion – State of the Art in Lung Donor Pool Expansion

    PubMed Central

    Popov, Aron-Frederik; Sabashnikov, Anton; Patil, Nikhil P.; Zeriouh, Mohamed; Mohite, Prashant N.; Zych, Bartlomiej; Saez, Diana Garcia; Schmack, Bastian; Ruhparwar, Arjang; Dohmen, Pascal M.; Karck, Matthias; Simon, Andre R.; Weymann, Alexander

    2015-01-01

    Lung transplantation remains the gold standard for patients with end-stage lung disease. Nevertheless, the number of suitable donor lungs for the increasing number of patients on the waiting list necessitates alternative tools to expand the lung donor pool. Modern preservation and lung assessment techniques could contribute to improved function in previously rejected lungs. Ex vivo lung perfusion (EVLP) already demonstrated its value in identification of transplantable grafts from the higher risk donor pool. Moreover, lungs from EVLP did not show significantly different postoperative results compared to standard criteria lungs. This could be explained by the reduction of the ischemia-reperfusion injury through EVLP application. The aim of this article is to review technical characteristics and the growing clinical EVLP experience with special attention to EVLP application for donation after cardiac death (DCD) lungs. PMID:25644463

  6. Utilization of the organ care system as ex-vivo lung perfusion after cold storage transportation.

    PubMed

    Mohite, P N; Maunz, O; Popov, A-F; Zych, B; Patil, N P; Simon, A R

    2015-11-01

    The Organ Care System (OCS) allows perfusion and ventilation of the donor lungs under physiological conditions. Ongoing trials to compare preservation with OCS Lung with standard cold storage do not include donor lungs with suboptimal gas exchange and donor lungs treated with OCS following cold storage transportation. We present a case of a 48-yr-old man who received such lungs after cold storage transportation treated with ex-vivo lung perfusion utilizing OCS.

  7. Lung perfusion and emphysema distribution affect the outcome of endobronchial valve therapy

    PubMed Central

    Thomsen, Christian; Theilig, Dorothea; Herzog, Dominik; Poellinger, Alexander; Doellinger, Felix; Schreiter, Nils; Schreiter, Vera; Schürmann, Dirk; Temmesfeld-Wollbrueck, Bettina; Hippenstiel, Stefan; Suttorp, Norbert; Hubner, Ralf-Harto

    2016-01-01

    The exclusion of collateral ventilation (CV) and other factors affect the clinical success of endoscopic lung volume reduction (ELVR). However, despite its benefits, the outcome of ELVR remains difficult to predict. We investigated whether clinical success could be predicted by emphysema distribution assessed by computed tomography scan and baseline perfusion assessed by perfusion scintigraphy. Data from 57 patients with no CV in the target lobe (TL) were retrospectively analyzed after ELVR with valves. Pulmonary function tests (PFT), St George’s Respiratory Questionnaire (SGRQ), and 6-minute walk tests (6MWT) were performed on patients at baseline. The sample was grouped into high and low levels at the median of TL perfusion, ipsilateral nontarget lobe (INL) perfusion, and heterogeneity index (HI). These groups were analyzed for association with changes in outcome parameters from baseline to 3 months follow-up. Compared to baseline, patients showed significant improvements in PFT, SGRQ, and 6MWT (all P≤0.001). TL perfusion was not associated with changes in the outcome. High INL perfusion was significantly associated with increases in 6MWT (P=0.014), and high HI was associated with increases in forced expiratory volume in 1 second (FEV1), (P=0.012). Likewise, there were significant correlations for INL perfusion and improvement of 6MWT (r=0.35, P=0.03) and for HI and improvement in FEV1 (r=0.45, P=0.001). This study reveals new attributes that associate with positive outcomes for patient selection prior to ELVR. Patients with high perfusions in INL demonstrated greater improvements in 6MWT, while patients with high HI were more likely to respond in FEV1. PMID:27354783

  8. Tomographic digital subtraction angiography for lung perfusion estimation in rodents

    SciTech Connect

    Badea, Cristian T.; Hedlund, Laurence W.; De Lin, Ming; Boslego Mackel, Julie S.; Samei, Ehsan; Allan Johnson, G.

    2007-05-15

    In vivo measurements of perfusion present a challenge to existing small animal imaging techniques such as magnetic resonance microscopy, micro computed tomography, micro positron emission tomography, and microSPECT, due to combined requirements for high spatial and temporal resolution. We demonstrate the use of tomographic digital subtraction angiography (TDSA) for estimation of perfusion in small animals. TDSA augments conventional digital subtraction angiography (DSA) by providing three-dimensional spatial information using tomosynthesis algorithms. TDSA is based on the novel paradigm that the same time density curves can be reproduced in a number of consecutive injections of {mu}L volumes of contrast at a series of different angles of rotation. The capabilities of TDSA are established in studies on lung perfusion in rats. Using an imaging system developed in-house, we acquired data for four-dimensional (4D) imaging with temporal resolution of 140 ms, in-plane spatial resolution of 100 {mu}m, and slice thickness on the order of millimeters. Based on a structured experimental approach, we optimized TDSA imaging providing a good trade-off between slice thickness, the number of injections, contrast to noise, and immunity to artifacts. Both DSA and TDSA images were used to create parametric maps of perfusion. TDSA imaging has potential application in a number of areas where functional perfusion measurements in 4D can provide valuable insight into animal models of disease and response to therapeutics.

  9. Perfusion measures from dynamic ICG scanning laser ophthalmoscopy

    NASA Astrophysics Data System (ADS)

    Larkin, Sean; Invernizzi, Alessandro; Beecher, David; Staurenghi, Giovanni; Holmes, Tim

    2010-02-01

    Movies acquired from fundus imaging using Indocyanine Green (ICG) and a scanning laser ophthalmoscope provide information for identifying vascular and other retinal abnormalities. Today, the main limitation of this modality is that it requires esoteric training for interpretation. A straightforward interpretation of these movies by objective measurements would aid in eliminating this training barrier. A software program has been developed and tested that produces and visualizes 2D maps of perfusion measures. The program corrects for frame-to-frame misalignment caused by eye motion, including rigid misalignment and warp. The alignment method uses a cross-correlation operation that automatically detects the distance due to motion between adjacent frames. The d-ICG movie is further corrected by removing flicker and vignetting artifacts. Each pixel in the corrected movie sequence is fit with a least-squares spline to yield a smooth intensity temporal profile. From the dynamics of these intensity curves, several perfusion measures are calculated. The most effective of these measures include a metric that represents the amount of time required for a vessel to fill with dye, a metric that represents the diffusion of dye, and a metric that is affected by local blood volume. These metrics are calculated from movies acquired before and after treatment for a neovascular condition. A comparison of these before and after measures may someday provide information to the clinician that helps them to evaluate disease progression and response to treatment.

  10. Adenosine A2A Agonist Improves Lung Function During Ex-vivo Lung Perfusion

    PubMed Central

    Emaminia, Abbas; LaPar, Damien J.; Zhao, Yunge; Steidle, John F.; Harris, David A.; Linden, Joel; Kron, Irving L.; Lau, Christine L.

    2012-01-01

    Background Ex-vivo lung perfusion (EVLP) is a novel technique to assess, and potentially repair marginal lungs that may otherwise be rejected for transplantation. Adenosine has been shown to protect against lung ischemia-reperfusion injury through its A2A receptor. We hypothesized that combining EVLP with adenosine A2A receptor agonist treatment would enhance lung functional quality and increase donor lung usage. Methods Eight bilateral pig lungs were harvested and flushed with cold Perfadex. After 14 hours storage at 4°C, EVLP was performed for 5 hours on two explanted lung groups: 1) Control group lungs (n=4), were perfused with Steen Solution and Dimethyl sulfoxide (DMSO), and 2) treated group lungs (n=4) received 10μM CGS21680, a selective A2A receptor agonist, in a Steen Solution-primed circuit. Lung histology, tissue cytokines, gas analysis and pulmonary function were compared between groups. Results Treated lungs demonstrated significantly less edema as reflected by wet-dry weight ratio (6.6 vs. 5.2, p<0.03) and confirmed by histology. In addition, treated lung demonstrated significantly lower levels of interferon gamma (45.1 vs. 88.5, p<0.05). Other measured tissue cytokines (interleukin (IL) 1 beta, IL-6, and IL-8) were lower in treatment group, but values failed to reach statistical significance. Oxygenation index was improved in the treated group (1.5 vs. 2.3, p<0.01) as well as mean airway pressure (10.3 vs. 13 p<0.009). Conclusions EVLP is a novel and efficient way to assess and optimize lung function and oxygen exchange within donor lungs, and the use of adenosine A2A agonist potentiates its potential. EVLP with the concomitant administration of A2A agonist may enhance donor lung quality and could increase the donor lung pool for transplantation. PMID:22051279

  11. Retinyl ester synthesis by the isolated perfused-ventilated neonatal rabbit lung.

    PubMed

    Zachman, R D

    1985-01-01

    Retinyl ester is present in lung but it is unknown if retinyl ester synthesis occurs in that organ. In this study, [3H]-Retinol was perfused into the pulmonary artery of isolated-perfused-ventilated neonatal rabbit lungs. Alumina chromatography was used to separate retinol from retinyl ester in hexane extracts of lung tissue. [3H]-Retinyl ester synthesis did occur and was perfusion time and perfusate [3H]-retinol concentration dependent. Documentation of [3H] retinyl ester synthesis was also made by HPLC analysis of the retinyl ester fraction before and after methanolic KOH hydrolysis. Isolated lung clearly can synthesize retinyl ester. PMID:4086204

  12. PREOPERATIVE PREDICTION OF LUNG FUNCTION IN PNEUMONECTOMY BY SPIROMETRY AND LUNG PERFUSION SCINTIGRAPHY

    PubMed Central

    Cukic, Vesna

    2012-01-01

    Introduction: Nowadays an increasing number of lung resections are being done because of the rising prevalence of lung cancer that occurs mainly in patients with limited lung function, what is caused by common etiologic factor - smoking cigarettes. Loss of lung tissue in such patients can worsen much the postoperative pulmonary function. So it is necessary to asses the postoperative pulmonary function especially after maximal resection, i.e. pneumonectomy. Objective: To check over the accuracy of preoperative prognosis of postoperative lung function after pneumonectomy using spirometry and lung perfusion scinigraphy. Material and methods: The study was done on 17 patients operated at the Clinic for thoracic surgery, who were treated previously at the Clinic for Pulmonary Diseases “Podhrastovi” in the period from 01. 12. 2008. to 01. 06. 2011. Postoperative pulmonary function expressed as ppoFEV1 (predicted postoperative forced expiratory volume in one second) was prognosticated preoperatively using spirometry, i.e.. simple calculation according to the number of the pulmonary segments to be removed and perfusion lung scintigraphy. Results: There is no significant deviation of postoperative achieved values of FEV1 from predicted ones obtained by both methods, and there is no significant differences between predicted values (ppoFEV1) obtained by spirometry and perfusion scintigraphy. Conclusion: It is necessary to asses the postoperative pulmonary function before lung resection to avoid postoperative respiratory failure and other cardiopulmonary complications. It is absolutely necessary for pneumonectomy, i.e.. maximal pulmonary resection. It can be done with great possibility using spirometry or perfusion lung scintigraphy. PMID:23378687

  13. Ventilation/Perfusion Positron Emission Tomography—Based Assessment of Radiation Injury to Lung

    SciTech Connect

    Siva, Shankar; Hardcastle, Nicholas; Kron, Tomas; Bressel, Mathias; Callahan, Jason; MacManus, Michael P.; Shaw, Mark; Plumridge, Nikki; Hicks, Rodney J.; Steinfort, Daniel; Ball, David L.; Hofman, Michael S.

    2015-10-01

    Purpose: To investigate {sup 68}Ga-ventilation/perfusion (V/Q) positron emission tomography (PET)/computed tomography (CT) as a novel imaging modality for assessment of perfusion, ventilation, and lung density changes in the context of radiation therapy (RT). Methods and Materials: In a prospective clinical trial, 20 patients underwent 4-dimensional (4D)-V/Q PET/CT before, midway through, and 3 months after definitive lung RT. Eligible patients were prescribed 60 Gy in 30 fractions with or without concurrent chemotherapy. Functional images were registered to the RT planning 4D-CT, and isodose volumes were averaged into 10-Gy bins. Within each dose bin, relative loss in standardized uptake value (SUV) was recorded for ventilation and perfusion, and loss in air-filled fraction was recorded to assess RT-induced lung fibrosis. A dose-effect relationship was described using both linear and 2-parameter logistic fit models, and goodness of fit was assessed with Akaike Information Criterion (AIC). Results: A total of 179 imaging datasets were available for analysis (1 scan was unrecoverable). An almost perfectly linear negative dose-response relationship was observed for perfusion and air-filled fraction (r{sup 2}=0.99, P<.01), with ventilation strongly negatively linear (r{sup 2}=0.95, P<.01). Logistic models did not provide a better fit as evaluated by AIC. Perfusion, ventilation, and the air-filled fraction decreased 0.75 ± 0.03%, 0.71 ± 0.06%, and 0.49 ± 0.02%/Gy, respectively. Within high-dose regions, higher baseline perfusion SUV was associated with greater rate of loss. At 50 Gy and 60 Gy, the rate of loss was 1.35% (P=.07) and 1.73% (P=.05) per SUV, respectively. Of 8/20 patients with peritumoral reperfusion/reventilation during treatment, 7/8 did not sustain this effect after treatment. Conclusions: Radiation-induced regional lung functional deficits occur in a dose-dependent manner and can be estimated by simple linear models with 4D-V/Q PET

  14. Distribution of lung blood on modified bilateral Glenn shunt evaluated by Tc-99m-MAA lung perfusion scintigraphy

    PubMed Central

    Si, Biao; Luan, Zhao-sheng; Wang, Tong-jian; Ning, Yan-song; Li, Na; Zhu, Meng; Liu, Zhong-min; Ding, Guang-hong; Qiao, Bin

    2016-01-01

    Abstract The aim of the present study was to determine the distribution of lung blood in a modified bilateral Glenn procedure designed in our institute with lung perfusion scintigraphy. Sixteen consecutive patients who underwent modified bilateral Glenn operation from 2011 to 2014 were enrolled in the study. The control group consisted of 7 patients who underwent bidirectional Glenn shunt. Radionuclide lung perfusion scintigraphy was performed using Tc-99m-macro aggregated albumin (MAA) in all patients. For the patients in modified bilateral Glenn group, the time at which the radioactivity accumulation peaked did not differ significantly between the right and left lung field (t = 0.608, P = 0.554). The incidence of perfusion abnormality in each lung lobe also did not differ significantly (P = 0.426 by Fisher exact test). The radioactive counts were higher in the right lung than in the left lung, but the difference was not statistically significant (t = 1.502, P = 0.157). Radioactive perfusion in the lower lung field was significantly greater than that in the upper field (t = 4.368, P < 0.001). Compared with that in the bidirectional Glenn group, the ratio of radioactivity in the right lung to that in left lung was significantly lower in the modified bilateral Glenn group (t = 3.686, P = 0.002). Lung perfusion scintigraphy confirmed the benefit of the modified bilateral Glenn shunt with regard to more balanced blood perfusion in both lungs. PMID:27661042

  15. Vascular effects of acetylcholine in the perfused rabbit lung

    SciTech Connect

    Cherry, P.D.; Gillis, C.N.

    1986-03-05

    Acetylcholine (ACh) relaxes large, isolated arteries by releasing an endothelium-derived relaxing factor (EDRF). The authors decided to determine if ACh releases EDRF in rabbit lungs (RL) perfused in situ and if chemical injury with tetradecanoyl phorbol myristate acetate (TPA) could modify EDRF release in RL and in rabbit pulmonary arteries (RPA) in vitro. RL were perfused at 15 ml/min with Krebs-dextran solution. 1 ..mu..M ACh infusion raised perfusion pressure (P) in RL that was blocked by 30 ..mu..M indomethacin (IND) in the perfusate. However, when IND-treated RL were perfused with the stable endoperoxide analog, U46619 (2-6nM) to increase P, ACh infusion (0.01-1.0 ..mu..M) consistently decreased elevated P. The vasodilator response to infusion of 1 ..mu..M ACh was acutely antagonized by infusion of either 20 ..mu..M quinacrine (Q) or 10 ..mu..M Fe/sup + +/-hemoglobin (Hb). ACh did not decrease P in IND-treated RL pre-equilibrated with Q or Hb. TPA (10 nM) antagonized ACh-reduction of P and the ACh-induced relaxation of isolated RPA. The TPA antagonism of ACh-relaxation of RPA was prevented by catalase (300 U/ml). From these results they conclude that: 1) ACh-induced vasoconstriction in RL depends on cyclooxygenase product(s). 2) IND unmasks ACh-induced vasodilatation in RL that is inhibited by Q and by Hb suggesting that the effect is mediated by EDRF. 3) TPA inhibits ACh-induced vasodilatation and relaxation of RPA via the release of H/sub 2/O/sub 2/ or a related oxidant that injures the endothelium.

  16. Successful emergent lung transplantation after remote ex vivo perfusion optimization and transportation of donor lungs.

    PubMed

    Wigfield, C H; Cypel, M; Yeung, J; Waddell, T; Alex, C; Johnson, C; Keshavjee, S; Love, R B

    2012-10-01

    A recent clinical trial provided evidence that ex vivo lung perfusion (EVLP) results in optimized human donor lungs for transplantation. Excellent recipient outcomes were documented after 4 h of normothermic perfusion. We report a clinical case utilizing remote EVLP to assess and improve function of initially otherwise unacceptable injured donor lungs followed by transportation and subsequent bilateral lung transplantation in a patient with virally induced refractory respiratory failure supported with extracorporeal membrane oxygenation. This is the first lung transplantation with the application of remote EVLP, wherein the donor lungs were transported from the donor hospital to a center for EVLP and then transported to another hospital for transplantation. It is also the first case of lung transplantation in the United States utilizing EVLP for functional optimization leading to successful transplantation. Organ procurement data, EVLP assessment, and the pre- and postoperative course of the recipient are presented. The available evidence supporting EVLP, the humanitarian and cooperative utilization of lungs otherwise discarded, are discussed. PMID:23009140

  17. Evaluating acellular versus cellular perfusate composition during prolonged ex vivo lung perfusion after initial cold ischaemia for 24 hours.

    PubMed

    Becker, Simon; Steinmeyer, Jasmin; Avsar, Murat; Höffler, Klaus; Salman, Jawad; Haverich, Axel; Warnecke, Gregor; Ochs, Matthias; Schnapper, Anke

    2016-01-01

    Normothermic ex vivo lung perfusion (EVLP) has developed as a powerful technique to evaluate particularly marginal donor lungs prior to transplantation. In this study, acellular and cellular perfusate compositions were compared in an identical experimental setting as no consensus has been reached on a preferred technique yet. Porcine lungs underwent EVLP for 12 h on the basis of an acellular or a cellular perfusate composition after 24 h of cold ischaemia as defined organ stress. During perfusion, haemodynamic and respiratory parameters were monitored. After EVLP, the lung condition was assessed by light and transmission electron microscopy. Aerodynamic parameters did not show significant differences between groups and remained within the in vivo range during EVLP. Mean oxygenation indices were 491 ± 39 in the acellular group and 513 ± 53 in the cellular group. Groups only differed significantly in terms of higher pulmonary artery pressure and vascular resistance in the cellular group. Lung histology and ultrastructure were largely well preserved after prolonged EVLP and showed only minor structural alterations which were similarly present in both groups. Prolonged acellular and cellular EVLP for 12 h are both feasible with lungs prechallenged by ischaemic organ stress. Physiological and ultrastructural analysis showed no superiority of either acellular or cellular perfusate composition.

  18. Scanning electron microscopic autoradiography of lung

    SciTech Connect

    Lauhala, K.E.; Sanders, C.L.; McDonald, K.E.

    1988-09-01

    Scanning electron microscopic (SEM) autoradiography of the lung is being used to determine the distribution of inhaled, alpha particle-emitting, plutonium dioxide particles. SEM autoradiography provides high visual impact views of alpha activity. Particles irradiating the bronchiolar epithelium were detected both on the bronchiolar surface and in peribronchiolar alveoli. The technique is being used to obtain quantitative data on the clearance rates of plutonium particles from bronchi and bronchioles.

  19. Ex vivo lung perfusion in clinical lung transplantation--state of the art.

    PubMed

    Andreasson, Anders S I; Dark, John H; Fisher, Andrew J

    2014-11-01

    Ex vivo lung perfusion (EVLP) has emerged as a new technique for assessing and potentially reconditioning human donor lungs previously unacceptable for clinical transplantation with the potential to dramatically push the limits of organ acceptability. With the recent introduction of portable EVLP, a new era in lung preservation may be upon us with the opportunity to also limit organ ischaemic times and potentially improve the outcome of donor lungs already deemed acceptable for transplantation. It took over half a century for the technique to evolve from basic theory to semi-automated circuits fit for clinical use that are now rapidly being adopted in transplant centres across the globe. With this field in constant evolution and many unanswered questions remaining, our review serves as an update on the state of the art of EVLP in clinical lung transplantation.

  20. Lung Radiofrequency Ablation: In Vivo Experimental Study with Low-Perfusion-Rate Multitined Electrodes

    SciTech Connect

    Crocetti, Laura Lencioni, Riccardo; Bozzi, Elena; Sbrana, Alberto; Bartolozzi, Carlo

    2008-05-15

    The purpose of this study was to investigate the feasibility and safety of lung radiofrequency (RF) ablation by using low-perfusion-rate, expandable, multitined electrodes in an in vivo animal model. Ten New Zealand White rabbits underwent RF ablation using low-perfusion-rate, expandable, multitined electrodes (Starburst Talon; RITA Medical Systems, Mountain View, CA) and a 200-W RF generator. The electrode was positioned under fluoroscopy guidance and a single percutaneous RF ablation was performed. Saline perfusate was doped with nonionic iodinated contrast agent to render it visible on computed tomography (CT). The pump infused the saline doped with contrast agent into the lateral tines at a rate of 0.1ml/min. The planned ablation was of 3 min, with the hooks deployed to 2 cm at a target temperature of 105{sup o}C. An immediate posttreatment CT scan documented the distribution of the doped saline and the presence of immediate complications. The animals were monitored for delayed complications and sacrificed within 72 h (n = 4), 2 weeks (n = 3), or 4 weeks (n = 3). Assessment of ablation zone and adjacent structures was done at autopsy. Major complications consisted of pneumothorax requiring drainage (n = 2) and skin burn (n = 1). Immediately after the procedure the area of ablation was depicted at CT as a round, well-demarcated area, homogeneously opacified by iodinated contrast medium (mean size, 2.3 {+-} 0.8 cm). The presence of a sharply demarcated area of coagulation necrosis (mean size, 2.1 {+-} 0.4 cm) without severe damage to adjacent structures was confirmed at autopsy. In one case, euthanized at 4 weeks, in whom pneumothorax and pleural effusion were depicted, pleural fibrinous adhesions were demonstrated at autopsy. In conclusion, lung RF ablation performed in an in vivo animal model using low-perfusion-rate, expandable, multitined electrodes is feasible and safe. No severe damage to adjacent structures was demonstrated.

  1. Role of Extracranial Carotid Duplex and Computed Tomography Perfusion Scanning in Evaluating Perfusion Status of Pericarotid Stenting

    PubMed Central

    Lin, Chih-Ming; Chang, Yu-Jun; Liu, Chi-Kuang; Yu, Cheng-Sheng

    2016-01-01

    Carotid stenting is an effective treatment of choice in terms of treating ischemic stroke patients with concomitant carotid stenosis. Though computed tomography perfusion scan has been recognized as a standard tool to monitor/follow up this group of patients, not everyone could endure due to underlying medical illness. In contrast, carotid duplex is a noninvasive assessment tool and could track patient clinical condition in real time. In this study we found that “resistance index” of the carotid ultrasound could detect flow changes before and after the stenting procedure, thus having great capacity to replace the role of computed tomography perfusion exam. PMID:27051669

  2. Kinetics of reversible-sequestration of leukocytes by the isolated perfused rat lung

    SciTech Connect

    Goliaei, B.

    1980-08-01

    The kinetics and morphology of sequestration and margination of rat leukocytes were studied using an isolated perfused and ventilated rat lung preparation. Whole rat blood, bone marrow suspension, or leukocyte suspensions, were used to perfuse the isolated rat lung. The lung was also perfused with latex particle suspensions and the passage of particles through the lung capillaries was studied. When a leukocyte suspension was perfused through the lung in the single-pass mode, the rate of sequestration decreased as more cells were perfused. In contrast, latex particles of a size comparable to that of leukocytes were totally stopped by the lung. When the leukocyte suspension was recirculated through the lung, cells were rapidly removed from circulation until a steady state was reached, after which no net removal of cells by the lung occurred. These results indicate that leukocytes are reversibly sequestered from circulation. The sequestered cells marginated and attached to the luminal surface of the endothelium of post-capillary venules and veins. A mathematical model was developed based on the assumption that the attachment and detachment of leukocytes to blood vessel walls follows first-order kinetics. The model correctly predicts the following characteristics of the system: (a) the kinetics of the sequestration of leukocytes by the lung; (b) the existence of a steady state when a suspension of leukocytes is recirculated through the lung; and (c) the independence of the fraction of cells remaining in circulation from the starting concentration for all values of starting concentration. (ERB)

  3. Pancreas tumor model in rabbit imaged by perfusion CT scans

    NASA Astrophysics Data System (ADS)

    Gunn, Jason; Tichauer, Kenneth; Moodie, Karen; Kane, Susan; Hoopes, Jack; Stewart, Errol E.; Hadway, Jennifer; Lee, Ting-Yim; Pereira, Stephen P.; Pogue, Brian W.

    2013-03-01

    The goal of this work was to develop and validate a pancreas tumor animal model to investigate the relationship between photodynamic therapy (PDT) effectiveness and photosensitizer drug delivery. More specifically, this work lays the foundation for investigating the utility of dynamic contrast enhanced blood perfusion imaging to be used to inform subsequent PDT. A VX2 carcinoma rabbit cell line was grown in the tail of the pancreas of three New Zealand White rabbits and approximately 3-4 weeks after implantation the rabbits were imaged on a CT scanner using a contrast enhanced perfusion protocol, providing parametric maps of blood flow, blood volume, mean transit time, and vascular permeability surface area product.

  4. Graft downsizing during ex vivo lung perfusion: case report and technical notes.

    PubMed

    Nosotti, M; Rosso, L; Mendogni, P; Tosi, D; Palleschi, A; Righi, I; Froio, S; Valenza, F; Santambrogio, L

    2014-09-01

    Among patients with respiratory insufficiency awaiting lung transplantation, small adult patients have a lower opportunity of receiving size-matched pulmonary grafts, because of the shortage of donors, particularly those of small size. Reducing the size of an oversized graft is one of the methods to increase the donor pool; similarly, ex vivo lung perfusion is an emerging technique aimed toward the same purpose. We describe how we combined the 2 techniques (lobar transplantation plus contralateral nonanatomic graft reduction during ex vivo lung perfusion) to overcome graft shortage in a clinical case. For the 1st time, this case report demonstrates that surgical manipulation during ex vivo lung perfusion does not affect the functional improvement in a lung previously judged to be not suitable for transplantation. The 6-month follow-up results are similar to those of standard bilateral lung transplantation.

  5. Simulation model for contrast agent dynamics in brain perfusion scans.

    PubMed

    Bredno, Jörg; Olszewski, Mark E; Wintermark, Max

    2010-07-01

    Standardization efforts are currently under way to reduce the heterogeneity of quantitative brain perfusion methods. A brain perfusion simulation model is proposed to generate test data for an unbiased comparison of these methods. This model provides realistic simulated patient data and is independent of and different from any computational method. The flow of contrast agent solute and blood through cerebral vasculature with disease-specific configurations is simulated. Blood and contrast agent dynamics are modeled as a combination of convection and diffusion in tubular networks. A combination of a cerebral arterial model and a microvascular model provides arterial-input and time-concentration curves for a wide range of flow and perfusion statuses. The model is configured to represent an embolic stroke in one middle cerebral artery territory and provides physiologically plausible vascular dispersion operators for major arteries and tissue contrast agent retention functions. These curves are fit to simpler template curves to allow the use of the simulation results in multiple validation studies. A gamma-variate function with fit parameters is proposed as the vascular dispersion operator, and a combination of a boxcar and exponential decay function is proposed as the retention function. Such physiologically plausible operators should be used to create test data that better assess the strengths and the weaknesses of various analysis methods.

  6. Ex Vivo Lung Perfusion and Transplant: State of the Art and View to the Future.

    PubMed

    Mohamed, Mohamed S A

    2015-12-01

    After the first clinical application of ex vivo lung perfusion in 2001, the technique has been used in many lung transplant centers worldwide. In addition, many modifications have been tested, leading to the development of various ex vivo lung perfusion systems and application protocols. Currently, the Lund protocol, the Toronto protocol, and Organ Care System Lung protocol are the clinically applied ex vivo lung perfusion protocols, based on the favorable results of the safety studies. Accordingly, the comparison among these EVLP systems and protocols should be an important research target, in order to provide the evidence based medical data that would recommend one protocol over the others. In this manuscript, the current experience with EVLP is reviewed and some molecular and clinical targets, that could be used to compare the various protocols of the technique, are introduced.

  7. (68)Ga PET Ventilation and Perfusion Lung Imaging-Current Status and Future Challenges.

    PubMed

    Bailey, Dale L; Eslick, Enid M; Schembri, Geoffrey P; Roach, Paul J

    2016-09-01

    Gallium-68 ((68)Ga) is a positron-emitting radionuclide suitable for positron emission tomography (PET) imaging that has a number of convenient features-it has a physical half life of 68 minutes, it is generator produced at the PET facility and needs no local cyclotron, and being a radiometal is able to be chelated to a number of useful molecules for diagnostic imaging with PET. (68)Ga has recently been investigated as a radiotracer for ventilation and perfusion (V/Q) lung imaging. It is relatively easy to produce both V/Q radiopharmaceuticals labeled with (68)Ga for PET studies, it offers higher spatial resolution than equivalent SPECT studies, the short half life allows for multiple (repeated) scans on the same day, and low amounts of radiotracer can be used thus limiting the radiation dose to the subject. In the usual clinical setting requiring a V/Q scan, that of suspected pulmonary embolism, the role of (68)Ga V/Q PET may be limited from a logistical perspective, however, in nonacute applications such as lung function evaluation, radiotherapy treatment planning, and respiratory physiology investigations it would appear to be an ideal modality to employ. PMID:27553468

  8. Surface fluorescence studies of tissue mitochondrial redox state in isolated perfused rat lungs.

    PubMed

    Staniszewski, Kevin; Audi, Said H; Sepehr, Reyhaneh; Jacobs, Elizabeth R; Ranji, Mahsa

    2013-04-01

    We designed a fiber-optic-based optoelectronic fluorometer to measure emitted fluorescence from the auto-fluorescent electron carriers NADH and FAD of the mitochondrial electron transport chain (ETC). The ratio of NADH to FAD is called the redox ratio (RR = NADH/FAD) and is an indicator of the oxidoreductive state of tissue. We evaluated the fluorometer by measuring the fluorescence intensities of NADH and FAD at the surface of isolated, perfused rat lungs. Alterations of lung mitochondrial metabolic state were achieved by the addition of rotenone (complex I inhibitor), potassium cyanide (KCN, complex IV inhibitor) and/or pentachlorophenol (PCP, uncoupler) into the perfusate recirculating through the lung. Rotenone- or KCN-containing perfusate increased RR by 21 and 30%, respectively. In contrast, PCP-containing perfusate decreased RR by 27%. These changes are consistent with the established effects of rotenone, KCN, and PCP on the redox status of the ETC. Addition of blood to perfusate quenched NADH and FAD signal, but had no effect on RR. This study demonstrates the capacity of fluorometry to detect a change in mitochondrial redox state in isolated perfused lungs, and suggests the potential of fluorometry for use in in vivo experiments to extract a sensitive measure of lung tissue health in real-time.

  9. Perfusion and ventilation filters for Fourier-decomposition MR lung imaging.

    PubMed

    Wujcicki, Artur; Corteville, Dominique; Materka, Andrzej; Schad, Lothar R

    2015-03-01

    MR imaging without the use of contrast agents has recently been used for creating perfusion and ventilation functional lung images. The technique incorporates frequency- or wavelet-domain filters to separate the MR signal components. This paper presents a new, subject-adaptive algorithm for perfusion and ventilation filters design. The proposed algorithm uses a lung signal model for separation of the signal components in the frequency domain. Non-stationary lung signals are handled by a short time Fourier transform. This method was applied to sets of 192 and 90 co-registered non-contrast MR lung images measured for five healthy subjects at the rate of 3,33 images per second, using different slice thicknesses. In each case, the resulted perfusion and ventilation images showed a smaller amount of mutual information, when compared to those obtained using the known lowpass/highpass filter approach.

  10. Qualitative evaluation of coronary flow during anesthetic induction using thallium-201 perfusion scans

    SciTech Connect

    Kleinman, B.; Henkin, R.E.; Glisson, S.N.; el-Etr, A.A.; Bakhos, M.; Sullivan, H.J.; Montoya, A.; Pifarre, R.

    1986-02-01

    Qualitative distribution of coronary flow using thallium-201 perfusion scans immediately postintubation was studied in 22 patients scheduled for elective coronary artery bypass surgery. Ten patients received a thiopental (4 mg/kg) and halothane induction. Twelve patients received a fentanyl (100 micrograms/kg) induction. Baseline thallium-201 perfusion scans were performed 24 h prior to surgery. These scans were compared with the scans performed postintubation. A thallium-positive scan was accepted as evidence of relative hypoperfusion. Baseline hemodynamic and ECG data were obtained prior to induction of anesthesia. These data were compared with the data obtained postintubation. Ten patients developed postintubation thallium-perfusion scan defects (thallium-positive scan), even though there was no statistical difference between their baseline hemodynamics and hemodynamics at the time of intubation. There was no difference in the incidence of thallium-positive scans between those patients anesthetized by fentanyl and those patients anesthetized with thiopental-halothane. The authors conclude that relative hypoperfusion, and possibly ischemia, occurred in 45% of patients studied, despite stable hemodynamics, and that the incidence of these events was the same with two different anesthetic techniques.

  11. Investigation of the potential causes of partial scan artifacts in dynamic CT myocardial perfusion imaging

    NASA Astrophysics Data System (ADS)

    Tao, Yinghua; Speidel, Michael; Szczykutowicz, Timothy; Chen, Guang-Hong

    2014-03-01

    In recent years, there have been several findings regarding CT number variations (partial scan artifact or PSA) across time in dynamic myocardial perfusion studies with short scan gated reconstruction. These variations are correlated with the view angle range corresponding to the short scan acquisition for a given cardiac phase, which can vary from one cardiac cycle to another due to the asynchrony between heart rate and gantry rotation speed. In this study, we investigate several potential causes of PSA, including noise, beam hardening and scatter, using numerical simulations. In addition, we investigate partial scan artifact in a single source 64-slice diagnostic CT scanner in vivo data sets, and report its effect on perfusion analysis. Results indicated that among all three factors investigated, scatter can cause obvious partial scan artifact in dynamic myocardial perfusion imaging. Further, scatter is a low frequency phenomenon and is not heavily dependent on the changing contrasts, as both the frequency method and the virtual scan method are effective in reducing partial scan artifact. However, PSA does not necessarily lead to different blood volume maps compared to the full scan, because these maps are usually generated with a curve fitting procedure.

  12. Conversion of choline to phosphatidylcholine in the isolated-ventilated-perfused neonatal rabbit lung.

    PubMed

    Zachman, R D; Cotter, P W; Tsao, F H

    1983-01-01

    The isolated-ventilated-perfused neonatal rabbit lung model was used to study pulse dosed 14C-choline incorporation into 14C-phosphatidylcholine (PC) and 14C-disaturated phosphatidylcholine (DSPC). 14C-PC and 14C-DSPC synthesis were linearly dependent upon perfusion time to 30 min and upon the pulse dose of 14C-choline of 20-250 nmol at both 10 and 30 min of perfusion. 2-3% of the pulse-dosed choline was taken up by the lung. The water-soluble metabolites of choline found in lung after 10-30 min of perfusion were: choline, 50-60%; betaine 2.4-3.0%; phosphorylcholine, 26-41%, and CDP-choline, trace-10%. 1-day-old perfused lungs incorporated pulse-dosed 14C-choline into 14C-PC and 14C-DSPC at slightly higher rates than at 10 days old. Newborn rabbits receiving an intraperitoneal injection of 0.1 mg dexamethasone/100 g body weight 16 and 22 h prior to perfusion incorporated significantly more 14C-choline into 14C-PC and 14C-DSPC than saline-injected controls. PMID:6626622

  13. Quantification of nonuniform distribution of hemi-lung perfusion in chronic obstructive pulmonary disease.

    PubMed

    Mitomo, Osamu

    2016-01-01

    Nonuniform distribution (NUD) of perfusion on single photon emission computed tomography (SPECT) is caused by impaired perfusion-related fluctuations of the functional volume (FFV). It was determined if digital analysis of NUD in each hemi-lung damaged by chronic obstructive pulmonary disease (COPD) could improve the whole lung impairment assessment. We examined 665 subjects and 8 controls by SPECT. The basic whole lung SPECT volume was defined at 10% of maximum whole lung count cutoff threshold (T h). For the whole lung and each hemi-lung, the 10% T h width volume, FFV rate, and misfit from the control were calculated at every T h width number (n) from 1 to 9 for every additional 10% T h from 10 to 100%. The misfit value integrated from 1 to 9 of n was defined by 3 NUD indices: D, whole lung NUD index; D rl , the index for the sum of each hemi-lung NUD; and D (I) , the NUD index with every interpolating pattern in which FFV rates of hemi-lungs comprised negative and positive value at the same n. D rl index was the sum of D and D (I) indices in all patients. D rl and D indices significantly increased in pulmonary disease subjects relative to those of the normal group and non-pulmonary disease subjects. D rl and D indices increased in COPD subjects. Progressive COPD subjects had larger D rl index values and "diffuse and even" hemi-lung impairment. The three indices quantizing FFV itself leading to NUD helped to digitally evaluate the degree of lung impairment of perfusion. Clinically, it is expected that the NUD indices and images obtained by SPECT, which visually and digitally show the pathological fluctuations in perfusion caused by lung impairment, will be able to provide specific and useful information for improving treatment and/or care of subjects with COPD.

  14. Changes in distribution of lung perfusion and ventilation at rest and during maximal exercise

    SciTech Connect

    Mohsenifar, Z.; Ross, M.D.; Waxman, A.; Goldbach, P.; Koerner, S.K.

    1985-03-01

    A new method for evaluation of changes in the distribution of pulmonary perfusion and ventilation during exercise was applied to normal male volunteers. Ventilation and perfusion scans were done with the subjects seated on a bicycle ergometer. The resting studies utilized krypton 81 (/sup 81m/Kr) for ventilation and technetium /sup 99m/ (/sup 99m/Tc) macroaggregate albumin intravenously for perfusion. Exercise studies were done when 80 percent of maximum predicted heart rate was maintained for five minutes and utilized /sup 81m/Kr for ventilation and a tenfold dose of /sup 99m/Tc for perfusion. Higher dose of /sup 99m/Tc would minimize the effect of radioactivity left over from the resting study. This method allowed us to assess changes in ventilation and perfusion in normal subjects induced by exercise, but may also be applicable in a variety of cardiopulmonary conditions that affect pulmonary ventilation and perfusion or both.

  15. Effects of lung ventilation–perfusion and muscle metabolism–perfusion heterogeneities on maximal O2 transport and utilization

    PubMed Central

    Cano, I; Roca, J; Wagner, P D

    2015-01-01

    Previous models of O2 transport and utilization in health considered diffusive exchange of O2 in lung and muscle, but, reasonably, neglected functional heterogeneities in these tissues. However, in disease, disregarding such heterogeneities would not be justified. Here, pulmonary ventilation–perfusion and skeletal muscle metabolism–perfusion mismatching were added to a prior model of only diffusive exchange. Previously ignored O2 exchange in non-exercising tissues was also included. We simulated maximal exercise in (a) healthy subjects at sea level and altitude, and (b) COPD patients at sea level, to assess the separate and combined effects of pulmonary and peripheral functional heterogeneities on overall muscle O2 uptake ( and on mitochondrial (). In healthy subjects at maximal exercise, the combined effects of pulmonary and peripheral heterogeneities reduced arterial () at sea level by 32 mmHg, but muscle by only 122 ml min−1 (–3.5%). At the altitude of Mt Everest, lung and tissue heterogeneity together reduced by less than 1 mmHg and by 32 ml min−1 (–2.4%). Skeletal muscle heterogeneity led to a wide range of potential among muscle regions, a range that becomes narrower as increases, and in regions with a low ratio of metabolic capacity to blood flow, can exceed that of mixed muscle venous blood. For patients with severe COPD, peak was insensitive to substantial changes in the mitochondrial characteristics for O2 consumption or the extent of muscle heterogeneity. This integrative computational model of O2 transport and utilization offers the potential for estimating profiles of both in health and in diseases such as COPD if the extent for both lung ventilation–perfusion and tissue metabolism–perfusion heterogeneity is known. PMID:25640017

  16. [Role of membrane protectors and antioxidants in the process of perfusion and preservation of donor lungs].

    PubMed

    Khodzhimatov, G M; Movsesov, R V; Zhidkov, I L; Zhavoronkov, N A; Ivanova, A G; Dement'eva, I I; Perel'man, M I

    1997-01-01

    Comparative study of the effect of four perfusion and preservation solutions on lung function, conducted in experiments on 69 inbred dogs, revealed the following regular features. Euro-Collins and electrolyte solutions cause a marked increase of the capillary-hydrostatic pressure, a significant decrease of colloido-osmotic pressure of the plasma, and, as a result, reduction of the ient between them. This is manifested by edema of the lungs. The use of LPD solution is attended by moderate edema of the lungs in moderately increased capillary hydrostatic pressure and mildly reduced colloido-osmotic pressure of the plasma. Perfusion and preservation of the lungs with the LPD solution, containing membrane protectors and antioxidants, for 12 hours is marked by practically unchanged indices of capillary-hydrostatic pressure, plasma coloido-osmotic pressure, and the gradient between them. Edema of the lungs does not develop in this case.

  17. Effect of carbon monoxide on xenobiotic metabolism in the isolated perfused rabbit lung

    SciTech Connect

    Trela, B.A.

    1988-01-01

    It was the aim of this study to determine the level and duration of CO exposure necessary to alter mixed function oxidase-mediated activity in the intact lung and to determine the magnitude of this effect. The effect of CO on the mixed function oxidase-mediated activities of aminopyrine, aniline, 4-ipomeanol and p-nitroanisole in isolated perfused rabbit lungs (IPRL) was investigated. Several concentrations of CO were evaluated for their effect on cytochrome P-450-mediated activity in the lung. Both artificial medium and whole blood were utilized as recirculating perfusates. Monomethyl-4-aminoantipyrine was the major metabolite of aminopyrine produced by in vitro hepatic and pulmonary preparations and by the intact lung. Ventilation of isolated rabbit lungs with 7.5% CO for 2.5 hours caused a 40% decrease in the rates of metabolism of both aminopyrine and p-nitroanisole. This level of CO exposure did not alter the cytochrome P-450-mediated metabolism of aniline nor 4-ipomeanol in the intact lung. Aminopyrine metabolism in isolated rabbit lungs perfused with whole blood was also decreased following the administration of 7.5% CO suggesting that the hemoglobin in whole blood affords no protection against CO-induced inhibition of mixed function oxidase activity in the intact lung. The isozyme of cytochrome P-450 which preferentially metabolizes aminopyrine and p-nitroanisole may be more sensitive to CO-induced inhibition than the form(s) which metabolize aniline and 4-ipomeanol.

  18. Distribution of lung blood on modified bilateral Glenn shunt evaluated by Tc-99m-MAA lung perfusion scintigraphy: A retrospective study.

    PubMed

    Si, Biao; Luan, Zhao-Sheng; Wang, Tong-Jian; Ning, Yan-Song; Li, Na; Zhu, Meng; Liu, Zhong-Min; Ding, Guang-Hong; Qiao, Bin

    2016-09-01

    The aim of the present study was to determine the distribution of lung blood in a modified bilateral Glenn procedure designed in our institute with lung perfusion scintigraphy. Sixteen consecutive patients who underwent modified bilateral Glenn operation from 2011 to 2014 were enrolled in the study. The control group consisted of 7 patients who underwent bidirectional Glenn shunt. Radionuclide lung perfusion scintigraphy was performed using Tc-99m-macro aggregated albumin (MAA) in all patients. For the patients in modified bilateral Glenn group, the time at which the radioactivity accumulation peaked did not differ significantly between the right and left lung field (t = 0.608, P = 0.554). The incidence of perfusion abnormality in each lung lobe also did not differ significantly (P = 0.426 by Fisher exact test). The radioactive counts were higher in the right lung than in the left lung, but the difference was not statistically significant (t = 1.502, P = 0.157). Radioactive perfusion in the lower lung field was significantly greater than that in the upper field (t = 4.368, P < 0.001). Compared with that in the bidirectional Glenn group, the ratio of radioactivity in the right lung to that in left lung was significantly lower in the modified bilateral Glenn group (t = 3.686, P = 0.002). Lung perfusion scintigraphy confirmed the benefit of the modified bilateral Glenn shunt with regard to more balanced blood perfusion in both lungs. PMID:27661042

  19. Distribution of lung blood on modified bilateral Glenn shunt evaluated by Tc-99m-MAA lung perfusion scintigraphy: A retrospective study.

    PubMed

    Si, Biao; Luan, Zhao-Sheng; Wang, Tong-Jian; Ning, Yan-Song; Li, Na; Zhu, Meng; Liu, Zhong-Min; Ding, Guang-Hong; Qiao, Bin

    2016-09-01

    The aim of the present study was to determine the distribution of lung blood in a modified bilateral Glenn procedure designed in our institute with lung perfusion scintigraphy. Sixteen consecutive patients who underwent modified bilateral Glenn operation from 2011 to 2014 were enrolled in the study. The control group consisted of 7 patients who underwent bidirectional Glenn shunt. Radionuclide lung perfusion scintigraphy was performed using Tc-99m-macro aggregated albumin (MAA) in all patients. For the patients in modified bilateral Glenn group, the time at which the radioactivity accumulation peaked did not differ significantly between the right and left lung field (t = 0.608, P = 0.554). The incidence of perfusion abnormality in each lung lobe also did not differ significantly (P = 0.426 by Fisher exact test). The radioactive counts were higher in the right lung than in the left lung, but the difference was not statistically significant (t = 1.502, P = 0.157). Radioactive perfusion in the lower lung field was significantly greater than that in the upper field (t = 4.368, P < 0.001). Compared with that in the bidirectional Glenn group, the ratio of radioactivity in the right lung to that in left lung was significantly lower in the modified bilateral Glenn group (t = 3.686, P = 0.002). Lung perfusion scintigraphy confirmed the benefit of the modified bilateral Glenn shunt with regard to more balanced blood perfusion in both lungs.

  20. Behavior of vascular resistance undergoing various pressure insufflation and perfusion on decellularized lungs.

    PubMed

    da Palma, Renata Kelly; Nonaka, Paula Naomi; Campillo, Noelia; Uriarte, Juan J; Urbano, Jessica Julioti; Navajas, Daniel; Farré, Ramon; Oliveira, Luis V F

    2016-05-01

    Bioengineering of functional lung tissue by using whole lung scaffolds has been proposed as a potential alternative for patients awaiting lung transplant. Previous studies have demonstrated that vascular resistance (Rv) could be altered to optimize the process of obtaining suitable lung scaffolds. Therefore, this work was aimed at determining how lung inflation (tracheal pressure) and perfusion (pulmonary arterial pressure) affect vascular resistance. This study was carried out using the lungs excised from 5 healthy male Sprague-Dawley rats. The trachea was cannulated and connected to a continuous positive airway pressure (CPAP) device to provide a tracheal pressure ranging from 0 to 15cmH2O. The pulmonary artery was cannulated and connected to a controlled perfusion system with continuous pressure (gravimetric level) ranging from 5 to 30cmH2O. Effective Rv was calculated by ratio of pulmonary artery pressure (PPA) by pulmonary artery flow (V'PA). Rv in the decellularized lungs scaffolds decreased at increasing V'PA, stabilizing at a pulmonary arterial pressure greater than 20cmH2O. On the other hand, CPAP had no influence on vascular resistance in the lung scaffolds after being subjected to pulmonary artery pressure of 5cmH2O. In conclusion, compared to positive airway pressure, arterial lung pressure markedly influences the mechanics of vascular resistance in decellularized lungs.

  1. Ventilation-perfusion scintigraphy in an adult with congenital unilateral hyperlucent lung

    SciTech Connect

    Wegener, W.A.; Velchik, M.G. )

    1990-10-01

    A variety of congenital and acquired etiologies can give rise to the radiographic finding of a unilateral hyperlucent lung. An unusual case of congenital lobar emphysema diagnosed in a young adult following the initial discovery of a hyperexpanded, hyperlucent lung is reported. Although subsequent bronchoscopy and radiologic studies detailed extensive anatomic abnormalities, functional imaging also played an important role in arriving at this rare diagnosis. In particular, ventilation-perfusion scintigraphy identified the small contralateral lung as the functional lung and helped narrow the differential diagnosis to etiologies involving obstructive airway disorders.

  2. Accuracy and Utility of Deformable Image Registration in {sup 68}Ga 4D PET/CT Assessment of Pulmonary Perfusion Changes During and After Lung Radiation Therapy

    SciTech Connect

    Hardcastle, Nicholas; Hofman, Michael S.; Hicks, Rodney J.; Callahan, Jason; Kron, Tomas; MacManus, Michael P.; Ball, David L.; Jackson, Price; Siva, Shankar

    2015-09-01

    Purpose: Measuring changes in lung perfusion resulting from radiation therapy dose requires registration of the functional imaging to the radiation therapy treatment planning scan. This study investigates registration accuracy and utility for positron emission tomography (PET)/computed tomography (CT) perfusion imaging in radiation therapy for non–small cell lung cancer. Methods: {sup 68}Ga 4-dimensional PET/CT ventilation-perfusion imaging was performed before, during, and after radiation therapy for 5 patients. Rigid registration and deformable image registration (DIR) using B-splines and Demons algorithms was performed with the CT data to obtain a deformation map between the functional images and planning CT. Contour propagation accuracy and correspondence of anatomic features were used to assess registration accuracy. Wilcoxon signed-rank test was used to determine statistical significance. Changes in lung perfusion resulting from radiation therapy dose were calculated for each registration method for each patient and averaged over all patients. Results: With B-splines/Demons DIR, median distance to agreement between lung contours reduced modestly by 0.9/1.1 mm, 1.3/1.6 mm, and 1.3/1.6 mm for pretreatment, midtreatment, and posttreatment (P<.01 for all), and median Dice score between lung contours improved by 0.04/0.04, 0.05/0.05, and 0.05/0.05 for pretreatment, midtreatment, and posttreatment (P<.001 for all). Distance between anatomic features reduced with DIR by median 2.5 mm and 2.8 for pretreatment and midtreatment time points, respectively (P=.001) and 1.4 mm for posttreatment (P>.2). Poorer posttreatment results were likely caused by posttreatment pneumonitis and tumor regression. Up to 80% standardized uptake value loss in perfusion scans was observed. There was limited change in the loss in lung perfusion between registration methods; however, Demons resulted in larger interpatient variation compared with rigid and B-splines registration

  3. Exclusion of pneumothorax by radionuclide lung scan

    SciTech Connect

    Weiss, P.E.

    1986-05-01

    A case is reported in which ventilation lung imaging was useful in excluding a large pneumothorax. This technique may be helpful in patients with emphysema in whom exclusion of pneumothorax by radiographic criteria might be difficult.

  4. Investigation of tomosynthetic perfusion measurements using the scanning-beam digital x-ray (SBDX) system

    NASA Astrophysics Data System (ADS)

    Nett, Brian E.; Chen, Guang-Hong; Van Lysel, Michael S.; Betts, Timothy; Speidel, Michael; Rowley, Howard A.; Aagaard Kienitz, Beverly D.; Mistretta, Charles A.

    2004-10-01

    The feasibility of making regional perfusion measurements using a tomosynthetic digital subtraction angiography (TDSA) acquisition has been demonstrated. The study of tomosynthetic perfusion measurements was motivated by the clinical desire for perfusion measurements in an interventional angiography suite. These pilot studies were performed using the scanning-beam digital x-ray (SBDX) system which is an inverse-geometry imaging device which utilizes an electromagnetically-scanned x-ray source, and a small CdTe direct conversion photon counting detector. The scanning electron source was used to acquire planar-tomographic images of a 12.5 x 12.5 cm field of view at a frame rate of 15 frames/sec during dynamic contrast injection. A beagle animal model was used to evaluate the tomosynthetic perfusion measurements. A manual bolus injection of iodinated contrast solution was used in order to resolve the parameters of the contrast pass curve. The acquired planar tomosynthetic dataset was reconstructed with a simple back-projection algorithm. Digital subtraction techniques were used to visualize the change in contrast agent intensity in each reconstructed plane. Given the TDSA images, region of interest based analysis was used in the selection of the image pixels corresponding to the artery and tissue bed. The mean transit time (MTT), regional cerebral blood volume (rCBV) and regional cerebral blood flow (rCBF) were extracted from the tomosynthetic data for selected regions in each of the desired reconstructed planes. For the purpose of this study, the arterial contrast enhancement curve was fit with a combination of gamma variate terms, and the MTT was calculated using a deconvolution based on the singular value decomposition (SVD). The results of the contrast pass curves derived with TDSA were consistent with the results from perfusion measurements as implemented with CT acquisition.

  5. Composite pseudocolor images: a technique to enhance the visual correlation between ventilation-perfusion lung images

    NASA Astrophysics Data System (ADS)

    Vaz de Carvalho, Carlos; Costa, Antonio A.; Seixas, M.; Ferreira, F. N.; Guedes, M. A.; Amaral, I.

    1993-07-01

    Lung ventilation and perfusion raw nuclear medicine images obtained from a gamma camera can be difficult to analyze on a per si basis. A method to optimize the visual correlation between these images was established through the use of new combination images: Composite Pseudo-Color (CPC) images. The major topic of this study is the assessment of the usefulness of this method in the detection of lung malfunction.

  6. Teaching Ventilation/Perfusion Relationships in the Lung

    ERIC Educational Resources Information Center

    Glenny, Robb W.

    2008-01-01

    This brief review is meant to serve as a refresher for faculty teaching respiratory physiology to medical students. The concepts of ventilation and perfusion matching are some of the most challenging ideas to learn and teach. Some strategies to consider in teaching these concepts are, first, to build from simple to more complex by starting with a…

  7. A General Approach to the Evaluation of Ventilation-Perfusion Ratios in Normal and Abnormal Lungs

    ERIC Educational Resources Information Center

    Wagner, Peter D.

    1977-01-01

    Outlines methods for manipulating multiple gas data so as to gain the greatest amount of insight into the properties of ventilation-perfusion distributions. Refers to data corresponding to normal and abnormal lungs. Uses a two-dimensional framework with the respiratory gases of oxygen and carbon dioxide. (CS)

  8. Active Oxygen Metabolites and Thromboxane in Phorbol Myristate Acetate Toxicity to the Isolated, Perfused Rat Lung.

    NASA Astrophysics Data System (ADS)

    Carpenter, Laurie Jean

    When administered intravenously or intratracheally to rats, rabbits and sheep, phorbol myristate acetate (PMA) produces changes in lung morphology and function are similar to those seen in humans with the adult respiratory distress syndrome (ARDS). Therefore, it is thought that information about the mechanism of ARDS development can be gained from experiments using PMA-treated animals. Currently, the mechanisms by which PMA causes pneumotoxicity are unknown. Results from other studies in rabbits and in isolated, perfused rabbit lungs suggest that PMA-induced lung injury is mediated by active oxygen species from neutrophils (PMN), whereas studies in sheep and rats suggest that PMN are not required for the toxic response. The role of PMN, active oxygen metabolites and thromboxane (TxA_2) in PMA-induced injury to isolated, perfused rat lungs (IPLs) was examined in this thesis. To determine whether PMN were required for PMA to produce toxicity to the IPL, lungs were perfused for 30 min with buffer containing various concentrations of PMA (in the presence or absence of PMN). When concentrations >=q57 ng/ml were added to medium devoid of added PMN, perfusion pressure and lung weight increased. When a concentration of PMA (14-28 ng/ml) that did not by itself cause lungs to accumulate fluid was added to the perfusion medium containing PMN (1 x 10 ^8), perfusion pressure increased, and lungs accumulated fluid. These results indicate that high concentrations of PMA produce lung injury which is independent of PMN, whereas injury induced by lower concentrations is PMN-dependent. To examine whether active oxygen species were involved in mediating lung injury induced by PMA and PMN, lungs were coperfused with the oxygen radical scavengers SOD and/or catalase. Coperfusion with either or both of these enzymes totally protected lungs against injury caused by PMN and PMA. These results suggest that active oxygen species (the hydroxyl radical in particular), mediate lung injury in

  9. Normothermic ex vivo perfusion prevents lung injury compared to extended cold preservation for transplantation.

    PubMed

    Cypel, M; Rubacha, M; Yeung, J; Hirayama, S; Torbicki, K; Madonik, M; Fischer, S; Hwang, D; Pierre, A; Waddell, T K; de Perrot, M; Liu, M; Keshavjee, S

    2009-10-01

    Treatment of injured donor lungs ex vivo to accelerate organ recovery and ameliorate reperfusion injury could have a major impact in lung transplantation. We have recently demonstrated a feasible technique for prolonged (12 h) normothermic ex vivo lung perfusion (EVLP). This study was performed to examine the impact of prolonged EVLP on ischemic injury. Pig donor lungs were cold preserved in Perfadex for 12 h and subsequently divided into two groups: cold static preservation (CSP) or EVLP at 37 degrees C with Steen solution for a further 12 h (total 24 h preservation). Lungs were then transplanted and reperfused for 4 h. EVLP preservation resulted in significantly better lung oxygenation (PaO(2) 531 +/- 43 vs. 244 +/- 49 mmHg, p < 0.01) and lower edema formation rates after transplantation. Alveolar epithelial cell tight junction integrity, evaluated by zona occludens-1 protein staining, was disrupted in the cell membranes after prolonged CSP but not after EVLP. The maintenance of integrity of barrier function during EVLP translates into significant attenuation of reperfusion injury and improved graft performance after transplantation. Integrity of functional metabolic pathways during normothermic perfusion was confirmed by effective gene transfer and GFP protein synthesis by lung alveolar cells. In conclusion, EVLP prevents ongoing injury associated with prolonged ischemia and accelerates lung recovery. PMID:19663886

  10. Quantifying single microvessel permeability in isolated blood-perfused rat lung preparation.

    PubMed

    Kandasamy, Kathirvel; Parthasarathi, Kaushik

    2014-01-01

    The isolated blood-perfused lung preparation is widely used to visualize and define signaling in single microvessels. By coupling this preparation with real time imaging, it becomes feasible to determine permeability changes in individual pulmonary microvessels. Herein we describe steps to isolate rat lungs and perfuse them with autologous blood. Then, we outline steps to infuse fluorophores or agents via a microcatheter into a small lung region. Using these procedures described, we determined permeability increases in rat lung microvessels in response to infusions of bacterial lipopolysaccharide. The data revealed that lipopolysaccharide increased fluid leak across both venular and capillary microvessel segments. Thus, this method makes it possible to compare permeability responses among vascular segments and thus, define any heterogeneity in the response. While commonly used methods to define lung permeability require postprocessing of lung tissue samples, the use of real time imaging obviates this requirement as evident from the present method. Thus, the isolated lung preparation combined with real time imaging offers several advantages over traditional methods to determine lung microvascular permeability, yet is a straightforward method to develop and implement.

  11. Pressure- and flow-controlled media perfusion differently modify vascular mechanics in lung decellularization.

    PubMed

    da Palma, Renata K; Campillo, Noelia; Uriarte, Juan J; Oliveira, Luis V F; Navajas, Daniel; Farré, Ramon

    2015-09-01

    Organ biofabrication is a potential future alternative for obtaining viable organs for transplantation. Achieving intact scaffolds to be recellularized is a key step in lung bioengineering. Perfusion of decellularizing media through the pulmonary artery has shown to be effective. How vascular perfusion pressure and flow vary throughout lung decellularization, which is not well known, is important for optimizing the process (minimizing time) while ensuring scaffold integrity (no barotrauma). This work was aimed at characterizing the pressure/flow relationship at the pulmonary vasculature and at how effective vascular resistance depends on pressure- and flow-controlled variables when applying different methods of media perfusion for lung decellularization. Lungs from 43 healthy mice (C57BL/6; 7-8 weeks old) were investigated. After excision and tracheal cannulation, lungs were inflated at 10 cmH2O airway pressure and subjected to conventional decellularization with a solution of 1% sodium dodecyl sulfate (SDS). Pressure (PPA) and flow (V'PA) at the pulmonary artery were continuously measured. Decellularization media was perfused through the pulmonary artery: (a) at constant PPA=20 cmH2O or (b) at constant V'PA=0.5 and 0.2 ml/min. Effective vascular resistance was computed as Rv=PPA/V'PA. Rv (in cmH2O/(ml/min)); mean±SE) considerably varied throughout lung decellularization, particularly for pressure-controlled perfusion (from 29.1±3.0 in baseline to a maximum of 664.1±164.3 (p<0.05), as compared with flow-controlled perfusion (from 49.9±3.3 and 79.5±5.1 in baseline to a maximum of 114.4±13.9 and 211.7±70.5 (p<0.05, both), for V'PA of 0.5 and 0.2 ml/min respectively. Most of the media infused to the pulmonary artery throughout decellularization circulated to the airways compartment across the alveolar-capillary membrane. This study shows that monitoring perfusion mechanics throughout decellularization provides information relevant for optimizing the process

  12. Do thallium myocardial perfusion scan abnormalities predict survival in sarcoid patients without cardiac symptoms

    SciTech Connect

    Kinney, E.L.; Caldwell, J.W. )

    1990-07-01

    Whereas the total mortality rate for sarcoidosis is 0.2 per 100,000, the prognosis, when the heart is involved, is very much worse. The authors used the difference in mortality rate to infer whether thallium 201 myocardial perfusion scan abnormalities correspond to myocardial sarcoid by making the simplifying assumption that if they do, then patients with abnormal scans will be found to have a death rate similar to patients with sarcoid heart disease. The authors therefore analyzed complete survival data on 52 sarcoid patients without cardiac symptoms an average of eighty-nine months after they had been scanned as part of a protocol. By use of survival analysis (the Cox proportional hazards model), the only variable that was significantly associated with survival was age. The patients' scan pattern, treatment status, gender, and race were not significantly related to survival. The authors conclude that thallium myocardial perfusion scans cannot reliably be used to diagnose sarcoid heart disease in sarcoid patients without cardiac symptoms.

  13. Noise filtering in thin-slice 4D cerebral CT perfusion scans

    NASA Astrophysics Data System (ADS)

    Mendrik, Adri"nne; Vonken, Evert-jan; Dankbaar, Jan-Willem; Prokop, Mathias; van Ginneken, Bram

    2010-03-01

    Patients suffering from cerebral ischemia or subarachnoid hemorrhage, undergo a 4D (3D+time) CT Perfusion (CTP) scan to assess the cerebral perfusion and a CT Angiography (CTA) scan to assess the vasculature. The aim of our research is to extract the vascular information from the CTP scan. This requires thin-slice CTP scans that suffer from a substantial amount of noise. Therefore noise reduction is an important prerequisite for further analysis. So far, the few noise filtering methods for 4D datasets proposed in literature deal with the temporal dimension as a 4th dimension similar to the 3 spatial dimensions, mixing temporal and spatial intensity information. We propose a bilateral noise reduction method based on time-intensity profile similarity (TIPS), which reduces noise while preserving temporal intensity information. TIPS was compared to 4D bilateral filtering on 10 patient CTP scans and, even though TIPS bilateral filtering is much faster, it results in better vessel visibility and higher image quality ranking (observer study) than 4D bilateral filtering.

  14. Microvascular perfusion during focal vasogenic brain edema: a scanning laser fluorescence microscopy study.

    PubMed

    Lindsberg, P J; Sirén, A L; Hallenbeck, J M

    1997-01-01

    Controversy exists about the effect of tissue edema on cerebral microcirculation. High spatial resolution is required for observation of extravasation and microcirculation during focal vasogenic edema formation. To study the relationship between tissue edema and perfusion, we developed a technique for simultaneous visualization of extravasation and microvessel perfusion in rats. Focal intracortical microvascular injury was generated with a 1-sec Nd-YAG laser pulse. Evans blue albumin (EBA) was infused 30 min before decapitation to study extravasation and FITC-dextran was injected 30 sec prior to decapitation to examine microvessel perfusion. Computerized scanning laser-excited fluorescence microscopy followed by high resolution image analysis permitted quantitative assessment of both parameters on single fresh-frozen brain sections. Studied at 30 min (3.66 +/- 0.15 mm), 2 hr (4.14 +/- 0.08 mm, P < .05), and 8 hr (4.69 +/- 0.18 mm, P < .01) after injury, the diameter of the circular, sharply demarcated zone of EBA-extravasation increased progressively. At 30 min, microvessels at a zone surrounding the area of EBA-extravasation contained 69 +/- 14% (P < .05) more fluorescent FITC-filling than in the control hemisphere, but the density of perfused microvessels was unchanged. At 2 hr, secondary tissue changes had already occurred in a zone surrounding the initial laser lesion. While severe reduction in the density (-76 +/- 13%, P < .05) of perfused microvessels was observed within 400 to 240 microm inside the border of EBA extravasation, perfusion indexes were normal despite the presence of extravasated plasma constituents within 0-80 microm from the border. In a narrow zone (80 microm) outside the border of extravasation, individual microvessels contained 34 +/- 9% (P < .01) less FITC-fluorescence than those in a homologous area of the uninjured contralateral hemisphere. This report demonstrates the feasibility of simultaneous measurement and high-resolution mapping

  15. Patterns of pulmonary perfusion scans in normal subjects. IV. The prevalence of abnormal scans in smokers 30 to 49 years of age

    SciTech Connect

    Fedullo, P.F.; Kapitan, K.S.; Brewer, N.S.; Ashburn, W.L.; Hartman, M.T.; Moser, K.M.

    1989-05-01

    The usefulness of ventilation-perfusion scans in the diagnosis of pulmonary embolism is limited by the wide range of pulmonary diseases that are associated with abnormal scans, and by the largely undetermined prevalence of abnormal scans in persons without cardiopulmonary disease. In prior studies, we found perfusion defects to be rarely present in young persons and in older nonsmokers. To determine if normal older smokers have a higher prevalence of abnormal ventilation and perfusion scans, we performed six-view /sup 99m/Tc perfusion (Q) scans and /sup 133/Xe ventilation (V) scans in 40 subjects 30 to 49 yr of age who had no known cardiopulmonary disease. Each subject had undergone a history, physical examination, electrocardiogram, spirometry, and posteroanterior chest roentgenogram prior to scanning. All V and Q scans were interpreted blindly and independently by two experienced readers. No subject demonstrated a lobar or segmental defect on two views. One subject had a matched subsegmental defect, and one subject had delayed washout from a subsegmental area of the right upper lobe during V scanning, with a normal Q scan. We conclude that abnormal V and Q scans are uncommon among normal smokers 30 to 49 yr of age.

  16. Ventilation-perfusion imaging in evaluating regional lung function in nonpenetrating injury to the chest.

    PubMed

    Van Eeden, S F; Klopper, J F; Alheit, B; Bardin, P G

    1989-03-01

    The extent of chest wall and lung injury after nonpenetrating injury to the chest (NIC) determine how aggressive and invasive management modalities should be. We investigated the value of ventilation (133Xe) and perfusion (99mTc) studies as indicators of extent of lung injury in 28 patients with moderate to severe unilateral NIC. The ventilation-perfusion (V/Q) abnormalities were compared with parameters conventionally used to evaluate NIC. All studies were carried out within 24 h of NIC and repeated 24 h later. Ventilation (p less than 0.001) and perfusion (p less than 0.01) abnormalities were more extensive soon after NIC than suggested by chest roentgenograms. Chest x-ray film changes lagged behind V/Q changes on admission and also after 24 h. The extent of ventilation, perfusion, and chest x-ray film abnormalities on admission were all predictors of increased morbidity. V/Q studies may be useful to define the extent as well as the changes in regional lung function following NIC.

  17. Comparison Between Postprocessing Software and Repeated Scanning to Eliminate Subdiaphragmatic Activity in Myocardial Perfusion Scintigraphy

    PubMed Central

    Theerakulpisut, Daris; Chotipanich, Chanisa

    2016-01-01

    Myocardial perfusion single photon emission computed tomography (SPECT) is a powerful test of evaluation for coronary artery disease, but subdiaphragmatic radiotracer activity often interferes with the interpretation of inferior wall findings. This study aims to evaluate the effectiveness of using software elimination of the subdiaphragmatic activity for the assessment of its efficacy in the correctness of image interpretation and the overall image quality of myocardial perfusion scintigraphy (MPS). MPS studies from January 2010 to October 2012 at our institution were reviewed. Thirty-two SPECT studies were included, all of which had significant subdiaphragmatic activity in the first scan and needed to be delayed to let the activity clear. Each scan was interpreted by using semiquantitative scoring in 17 segments according to the degree of radiotracer uptake. The first scan, which had interfering activity, was manipulated by masking out the unwanted activity with software native to our image processing software suite. The manipulated images were then compared with delayed images of the same patient, of which the subdiaphragmatic activity was spontaneously cleared with time. The first scan masked by software correlated with the delayed scan for myocardial regions supplied by the left circumflex (LCx) and right coronary artery (RCA), but not the left anterior descending (LAD). However, the quality of the masked scans was perceived by the observer to be better in terms of quality and ease of interpretation. Using software to mask out unwanted subdiaphragmatic activity has no detrimental effect on the interpretation of MPS images when compared with delayed scanning, but it can improve subjective scan quality and ease of interpretation. PMID:27134559

  18. Automated scoring of regional lung perfusion in children from contrast enhanced 3D MRI

    NASA Astrophysics Data System (ADS)

    Heimann, Tobias; Eichinger, Monika; Bauman, Grzegorz; Bischoff, Arved; Puderbach, Michael; Meinzer, Hans-Peter

    2012-03-01

    MRI perfusion images give information about regional lung function and can be used to detect pulmonary pathologies in cystic fibrosis (CF) children. However, manual assessment of the percentage of pathologic tissue in defined lung subvolumes features large inter- and intra-observer variation, making it difficult to determine disease progression consistently. We present an automated method to calculate a regional score for this purpose. First, lungs are located based on thresholding and morphological operations. Second, statistical shape models of left and right children's lungs are initialized at the determined locations and used to precisely segment morphological images. Segmentation results are transferred to perfusion maps and employed as masks to calculate perfusion statistics. An automated threshold to determine pathologic tissue is calculated and used to determine accurate regional scores. We evaluated the method on 10 MRI images and achieved an average surface distance of less than 1.5 mm compared to manual reference segmentations. Pathologic tissue was detected correctly in 9 cases. The approach seems suitable for detecting early signs of CF and monitoring response to therapy.

  19. Vasomotor tone does not affect perfusion heterogeneity and gas exchange in normal primate lungs during normoxia

    NASA Technical Reports Server (NTRS)

    Glenny, R. W.; Robertson, H. T.; Hlastala, M. P.

    2000-01-01

    To determine whether vasoregulation is an important cause of pulmonary perfusion heterogeneity, we measured regional blood flow and gas exchange before and after giving prostacyclin (PGI(2)) to baboons. Four animals were anesthetized with ketamine and mechanically ventilated. Fluorescent microspheres were used to mark regional perfusion before and after PGI(2) infusion. The lungs were subsequently excised, dried inflated, and diced into approximately 2-cm(3) pieces (n = 1,208-1,629 per animal) with the spatial coordinates recorded for each piece. Blood flow to each piece was determined for each condition from the fluorescent signals. Blood flow heterogeneity did not change with PGI(2) infusion. Two other measures of spatial blood flow distribution, the fractal dimension and the spatial correlation, did not change with PGI(2) infusion. Alveolar-arterial O(2) differences did not change with PGI(2) infusion. We conclude that, in normal primate lungs during normoxia, vasomotor tone is not a significant cause of perfusion heterogeneity. Despite the heterogeneous distribution of blood flow, active regulation of regional perfusion is not required for efficient gas exchange.

  20. Spectral imaging technique for retinal perfusion detection using confocal scanning laser ophthalmoscopy

    NASA Astrophysics Data System (ADS)

    Rasta, Seyed Hossein; Manivannan, Ayyakkannu; Sharp, Peter F.

    2012-11-01

    To evaluate retinal perfusion in the human eye, a dual-wavelength confocal scanning laser ophthalmoscope (cSLO) was developed that provides spectral imaging of the fundus using a combination of red (670 nm) and near-infrared (810 nm) wavelengths. The image of the ocular fundus was analyzed to find out if quantitative measurements of the reflectivity of tissue permit assessment of the oxygen perfusion of tissue. We explored problems that affect the reproducibility of patient measurements such as non-uniformity errors on the image. For the first time, an image processing technique was designed and used to minimize the errors of oxygen saturation measurements by illumination correction in retina wide field by increasing SNR. Retinal images were taken from healthy and diabetic retinopathy eyes using the cSLO with a confocal aperture of 100 μm. The ratio image (RI) of red/IR, as oxygen saturation (SO2) index, was calculated for normal eyes. The image correction technique improved the reproducibility of the measurements. Average RI intensity variation of healthy retina tissue was determined within a range of about 5.5%. The capability of the new technique to discriminate oxygenation levels of retinal artery and vein was successfully demonstrated and showed good promise in the diagnosis of the perfused retina.

  1. Optical studies of tissue mitochondrial redox in isolated perfused rat lungs

    NASA Astrophysics Data System (ADS)

    Sepehr, R.; Staniszewski, K.; Jacobs, E. R.; Audi, S.; Ranji, M.

    2012-02-01

    Through the monitoring of the auto-fluorescent mitochondrial metabolic coenzymes, NADH (Nicotinamide Adenine Dinucleotide) and FAD (Flavoprotein Adenine Dinucleotide), the redox state of metabolism can be probed in real time in many intact organs, but its use has not been fully developed in lungs. The ratio of these fluorophores, (NADH/FAD), referred to as the mitochondrial redox ratio (RR), can be used as a quantitative metabolic marker of tissue. We have designed a fluorometer that can be used to monitor lung surface NADH and FAD fluorescence in isolated perfused lungs. Surface fluorescence NADH and FAD signals were acquired in the absence (control) and presence of pentachlorophenol (PCP), rotenone, and potassium cyanide (KCN). Rotenone, an inhibitor of complex I, increased RR by 18%, predominantly due to an increase in NADH signal. KCN, an inhibitor of complex IV reduced the chain and resulted in an increase of 33% in RR, as a result of 23% increase in NADH and 8% in FAD . PCP, an uncoupler which oxidizes the respiratory chain, decreased RR by 18% as a result of 14% decrease in NADH signal and 4% increase in FAD signal. These results demonstrate the ability of surface fluorometry to detect changes in lung tissue mitochondrial redox state in isolated perfused lungs.

  2. Perfusion-Decellularization of Porcine Lung and Trachea for Respiratory Bioengineering.

    PubMed

    Weymann, Alexander; Patil, Nikhil Prakash; Sabashnikov, Anton; Korkmaz, Sevil; Li, Shiliang; Soos, Pal; Ishtok, Roland; Chaimow, Nicole; Pätzold, Ines; Czerny, Natalie; Schmack, Bastian; Popov, Aron-Frederik; Simon, Andre Rüdiger; Karck, Matthias; Szabo, Gabor

    2015-12-01

    Decellularization of native organs may provide an acellular tissue platform for organ regeneration. However, decellularization involves a trade-off between removal of immunogenic cellular elements and preservation of biomechanical integrity. We sought to develop a bioartificial scaffold for respiratory tissue engineering by decellularization of porcine lungs and trachea while preserving organ architecture and vasculature. Lung-trachea preparations from 25 German Landrace pigs were perfused in a modified Langendorff circuit and decellularized by an SDC (sodium deoxycholate)-based perfusion protocol. Decellularization was evaluated by histology and fluorescence microscopy, and residual DNA quantified spectrophotometrically and compared with controls. Airway compliance was evaluated by endotracheal intubation and mechanical ventilation to simulate physiological breathing-induced stretch. Structural integrity was evaluated by bronchoscopy and biomechanical stress/strain analysis by measuring passive tensile strength, all compared with controls. Decellularized lungs and trachea lacked intracellular components but retained specific collagen fibers and elastin. Quantitative DNA analysis demonstrated a significant reduction of DNA compared with controls (32.8 ± 12.4 μg DNA/mg tissue vs. 179.7 ± 35.8 μg DNA/mg tissue, P < 0.05). Lungs and trachea decellularized by our perfusion protocol demonstrated increased airway compliance but preserved biomechanical integrity as compared with native tissue. Whole porcine lungs-tracheae can be successfully decellularized to create an acellular scaffold that preserves extracellular matrix and retains structral integrity and three-dimensional architecture to provide a bioartifical platform for respiratory tissue engineering.

  3. Angiogenesis in tissue-engineered nerves evaluated objectively using MICROFIL perfusion and micro-CT scanning

    PubMed Central

    Wang, Hong-kui; Wang, Ya-xian; Xue, Cheng-bin; Li, Zhen-mei-yu; Huang, Jing; Zhao, Ya-hong; Yang, Yu-min; Gu, Xiao-song

    2016-01-01

    Angiogenesis is a key process in regenerative medicine generally, as well as in the specific field of nerve regeneration. However, no convenient and objective method for evaluating the angiogenesis of tissue-engineered nerves has been reported. In this study, tissue-engineered nerves were constructed in vitro using Schwann cells differentiated from rat skin-derived precursors as supporting cells and chitosan nerve conduits combined with silk fibroin fibers as scaffolds to bridge 10-mm sciatic nerve defects in rats. Four weeks after surgery, three-dimensional blood vessel reconstructions were made through MICROFIL perfusion and micro-CT scanning, and parameter analysis of the tissue-engineered nerves was performed. New blood vessels grew into the tissue-engineered nerves from three main directions: the proximal end, the distal end, and the middle. The parameter analysis of the three-dimensional blood vessel images yielded several parameters, including the number, diameter, connection, and spatial distribution of blood vessels. The new blood vessels were mainly capillaries and microvessels, with diameters ranging from 9 to 301 μm. The blood vessels with diameters from 27 to 155 μm accounted for 82.84% of the new vessels. The microvessels in the tissue-engineered nerves implanted in vivo were relatively well-identified using the MICROFIL perfusion and micro-CT scanning method, which allows the evaluation and comparison of differences and changes of angiogenesis in tissue-engineered nerves implanted in vivo. PMID:26981108

  4. Renal perfusion scintiscan

    MedlinePlus

    Renal perfusion scintigraphy; Radionuclide renal perfusion scan; Perfusion scintiscan - renal; Scintiscan - renal perfusion ... supply the kidneys. This is a condition called renal artery stenosis. Significant renal artery stenosis may be ...

  5. Localization of coronary artery disease with exercise electrocardiography: correlation with thallium-201 myocardial perfusion scanning

    SciTech Connect

    Dunn, R.F.; Freedman, B.; Bailey, I.K.; Uren, R.F.; Kelly, D.T.

    1981-11-01

    In 61 patients with single vessel coronary artery disease (70 percent or greater obstruction of luminal diameter in only one vessel) and no previous myocardial infarction, the sites of ischemic changes on 12 lead exercise electrocardiography and on thallium-201 myocardial perfusion scanning were related to the obstructed coronary artery. The site of exercise-induced S-T segment depression did not identify which coronary artery was obstructed. In the 37 patients with left anterior descending coronary artery disease S-T depression was most often seen in the inferior leads and leads V4 to V6, and in the 18 patients with right coronary artery disease and in the 6 patients with left circumflex artery disease S-T depression was most often seen in leads V5 and V6. Although S-T segment elevation was uncommon in most leads, it occurred in lead V1 or a VL, or both, in 51 percent of the patients with left anterior descending coronary artery disease. A reversible anterior defect on exercise thallium scanning correlated with left anterior descending coronary artery disease (probability (p) less than 0.0001) and a reversible inferior thallium defect correlated with right coronary or left circumflex artery disease (p less than 0.0001). In patients with single vessel disease, the site of S-T segment depression does not identify the obstructed coronary artery; S-T segment elevation in lead V1 or aVL, or both, identifies left anterior descending coronary artery disease; and the site of reversible perfusion defect on thallium scanning identifies the site of myocardial ischemia and the obstructed coronary artery.

  6. Effects of carbonic anhydrase inhibition on ventilation-perfusion matching in the dog lung.

    PubMed Central

    Swenson, E R; Robertson, H T; Hlastala, M P

    1993-01-01

    Lung carbonic anhydrase (CA) permits rapid pH responses when changes in regional ventilation or perfusion alter airway and alveolar PCO2. These pH changes affect airway and vascular resistances and lung compliance to optimize the balance of regional ventilation (VA) and perfusion (Q) in the lung. To test the hypothesis that these or other CA-dependent mechanisms contribute to VA/Q matching, we administered acetazolamide (25 mg/kg intravenously) to six anesthetized and paralyzed dogs and measured VA/Q relationships before and after CA inhibition by the multiple inert gas elimination technique. Four other groups of dogs were studied to control for possible confounding effects of time under anesthesia and nonselective CA inhibition by acetazolamide: (a) saline placebo as a control for duration of anesthesia, (b) 4% CO2 inhalation to mimic systemic CO2 retention, (c) 1 mg/kg benzolamide (a selective renal CA inhibitor) or 0.5 meq/kg HCl to mimic systemic metabolic acidosis, and (d) 500 mg/kg 4,4'-dinitrostilbene-2,2'-disulfonate (an inhibitor of red cell band 3 protein) to mimic the respiratory acidosis arising from an intracapillary block to rapid mobilization of plasma HCO3- in CO2 exchange. Acetazolamide increased VA/Q mismatch and reduced arterial PO2 measured at equilibrium but these did not occur in the control group. There was no deterioration in VA/Q matching when systemic respiratory acidosis produced either by CO2 inhalation or 4,4'-dinitrostilbene-2,2'-disulfonate or metabolic acidosis (benzolamide or HCl) were imposed to mimic the effects of acetazolamide apart from its inhibition of lung CA. These results support the concept that lung CA subserves VA/Q matching in the normal lung. Images PMID:8349809

  7. Lung transplantation with donation after circulatory determination of death donors and the impact of ex vivo lung perfusion.

    PubMed

    Machuca, T N; Mercier, O; Collaud, S; Tikkanen, J; Krueger, T; Yeung, J C; Chen, M; Azad, S; Singer, L; Yasufuku, K; de Perrot, M; Pierre, A; Waddell, T K; Keshavjee, S; Cypel, M

    2015-04-01

    The growing demand for suitable lungs for transplantation drives the quest for alternative strategies to expand the donor pool. The aim of this study is to evaluate the outcomes of lung transplantation (LTx) with donation after circulatory determination of death (DCDD) and the impact of selective ex vivo lung perfusion (EVLP). From 2007 to 2013, 673 LTx were performed, with 62 (9.2%) of them using DCDDs (seven bridged cases). Cases bridged with mechanical ventilation/extracorporeal life support were excluded. From 55 DCDDs, 28 (51%) underwent EVLP. Outcomes for LTx using DCDDs and donation after neurological determination of death (DNDD) donors were similar, with 1 and 5-year survivals of 85% and 54% versus 86% and 62%, respectively (p = 0.43). Although comparison of survival curves between DCDD + EVLP versus DCDD-no EVLP showed no significant difference, DCDD + EVLP cases presented shorter hospital stay (median 18 vs. 23 days, p = 0.047) and a trend toward shorter length of mechanical ventilation (2 vs. 3 days, p = 0.059). DCDDs represent a valuable source of lungs for transplantation, providing similar results to DNDDs. EVLP seems an important technique in the armamentarium to safely increase lung utilization from DCDDs; however, further studies are necessary to better define the role of EVLP in this context. PMID:25772069

  8. 12-tetradecanoyl-phorbol-13-acetate (PMA) produces injury to isolated rat lungs in the presence and absence of perfused neutrophils

    SciTech Connect

    Carpenter, L.J.; Roth, R.A.

    1986-03-01

    PMA produced injury to isolated, perfused rat lungs when eutrophils were added to or omitted from the buffer/albumin perfusion medium. When a high dose of PMA (57 ng/ml) was added to medium devoid of added neutrophils, perfusion pressure and lung weight increased. Together, superoxide dismutase (500 U/ml) and catalase (400 U/ml) had no effect on the increases in lung weight or perfusion pressure. However, papaverine (0.5 mM) prevented both the increase in perfusion pressure and fluid accumulation. When a concentration of PMA (14 ng/ml) that did not by itself cause lungs to accumulate fluid was added to perfusion medium containing neutrophils (1 x 10/sup 8/), perfusion pressures increased and lungs accumulated fluid. This concentration of PMA stimulated neutrophils (1 x 10/sup 8/) to release superoxide. Addition of superoxide dismutase (500 U/ml) and catalase (400 U/ml) to this medium prevented the increase in lung weight, but not the increase in perfusion pressure. Papaverine (0.5 mM) attenuated the increase in perfusion pressure and prevented fluid accumulation in these lungs. In summary, high concentrations of PMA produce lung injury which is independent of oxygen radicals; at lower concentrations it produces injury which is neutrophil-dependent and mediated by oxygen radicals.

  9. Automatic detection of the myocardial boundaries of the right and left ventricles in MR cardio perfusion scans

    NASA Astrophysics Data System (ADS)

    Spreeuwers, Luuk J.; Breeuwer, Marcel M.

    2001-07-01

    Recent advances in Magnetic Resonance Imaging allow fast recording of contrast enhanced myocardial perfusion scans. MR perfusion scans are made by recording, during a period of 20-40 seconds a number of short-axis slices through the myocardium. The scanning is triggered by the patient's ECG typically resulting in one set of slices per heart beat. For the perfusion analysis, the myocardial boundaries must be traced in all images Currently this is done manually, a tedious procedure, prone to inter- and intra-observer variability. In this paper a method for automatic detection of myocardial boundaries is proposed. This results in a considerable time reduction of the analysis and is an important step towards automatic analysis of cardiac MR perfusion scans. The most important consideration in the proposed approach is the use of not only spatial-intensity information, but also intensity-time and shape information to realize a robust segmentation. The procedure was tested on a total of 30 image sequences from 14 different scans. From 26 out of 30 sequences the myocardial boundaries were correctly found. The remaining 4 sequences were of very low quality and would most likely not be used for analysis.

  10. Perfusion of isolated organs and the first heart-lung machine.

    PubMed

    Zimmer, H G

    2001-09-01

    In 1885, Max von Frey (1852-1932), while working in Carl Ludwig's Physiological Institute in Leipzig, Germany, designed an apparatus that had criteria characteristic of a heart-lung machine. With this device, he perfused the entire lower extremity of dogs, and took measurements of oxygen consumption, and carbon dioxide and lactate production. In 1935, another type of perfusion apparatus was constructed by Charles A Lindbergh (1902-1973). This device was the result of cooperation with Alexis Carrel (1873-1944) who was a pioneer of experimental organ transplantation. Using Lindbergh's pulsating device, organs such as thyroid, ovary, suprarenal gland, spleen, heart and kidney from fowls and cats were perfused with an oxygenated medium, and were maintained under sterile conditions. Beginning in 1934, John H Gibbon (1903-1973) developed and tested a heart-lung machine to institute cardiopulmonary bypass in cats during experimental occlusion of the pulmonary artery. In 1953, he performed the first successful open-heart operation in a patient using a heart-lung machine. This included elements that were similar to those used by von Frey - ie, the oxygenator and the pumps for continuous circulation of blood. A comparison of the three experimental devices revealed the following: the application for experimental purposes preceded clinical use; the development shifted from Europe to the United States, and was achieved by people who were not specialists; and the intention to build such a device was first purely scientific interest, but later shifted to the care for and treatment of patients with heart and circulatory defects by open-heart surgery. PMID:11586387

  11. Implementation and evaluation of a new workflow for registration and segmentation of pulmonary MRI data for regional lung perfusion assessment

    NASA Astrophysics Data System (ADS)

    Böttger, T.; Grunewald, K.; Schöbinger, M.; Fink, C.; Risse, F.; Kauczor, H. U.; Meinzer, H. P.; Wolf, Ivo

    2007-03-01

    Recently it has been shown that regional lung perfusion can be assessed using time-resolved contrast-enhanced magnetic resonance (MR) imaging. Quantification of the perfusion images has been attempted, based on definition of small regions of interest (ROIs). Use of complete lung segmentations instead of ROIs could possibly increase quantification accuracy. Due to the low signal-to-noise ratio, automatic segmentation algorithms cannot be applied. On the other hand, manual segmentation of the lung tissue is very time consuming and can become inaccurate, as the borders of the lung to adjacent tissues are not always clearly visible. We propose a new workflow for semi-automatic segmentation of the lung from additionally acquired morphological HASTE MR images. First the lung is delineated semi-automatically in the HASTE image. Next the HASTE image is automatically registered with the perfusion images. Finally, the transformation resulting from the registration is used to align the lung segmentation from the morphological dataset with the perfusion images. We evaluated rigid, affine and locally elastic transformations, suitable optimizers and different implementations of mutual information (MI) metrics to determine the best possible registration algorithm. We located the shortcomings of the registration procedure and under which conditions automatic registration will succeed or fail. Segmentation results were evaluated using overlap and distance measures. Integration of the new workflow reduces the time needed for post-processing of the data, simplifies the perfusion quantification and reduces interobserver variability in the segmentation process. In addition, the matched morphological data set can be used to identify morphologic changes as the source for the perfusion abnormalities.

  12. Multislice CT perfusion imaging of the lung in detection of pulmonary embolism

    NASA Astrophysics Data System (ADS)

    Hong, Helen; Lee, Jeongjin

    2006-03-01

    We propose a new subtraction technique for accurately imaging lung perfusion and efficiently detecting pulmonary embolism in chest MDCT angiography. Our method is composed of five stages. First, optimal segmentation technique is performed for extracting same volume of the lungs, major airway and vascular structures from pre- and post-contrast images with different lung density. Second, initial registration based on apex, hilar point and center of inertia (COI) of each unilateral lung is proposed to correct the gross translational mismatch. Third, initial alignment is refined by iterative surface registration. For fast and robust convergence of the distance measure to the optimal value, a 3D distance map is generated by the narrow-band distance propagation. Fourth, 3D nonlinear filter is applied to the lung parenchyma to compensate for residual spiral artifacts and artifacts caused by heart motion. Fifth, enhanced vessels are visualized by subtracting registered pre-contrast images from post-contrast images. To facilitate visualization of parenchyma enhancement, color-coded mapping and image fusion is used. Our method has been successfully applied to ten patients of pre- and post-contrast images in chest MDCT angiography. Experimental results show that the performance of our method is very promising compared with conventional methods with the aspects of its visual inspection, accuracy and processing time.

  13. A database for estimating organ dose for coronary angiography and brain perfusion CT scans for arbitrary spectra and angular tube current modulation

    SciTech Connect

    Rupcich, Franco; Badal, Andreu; Kyprianou, Iacovos; Schmidt, Taly Gilat

    2012-09-15

    Purpose: The purpose of this study was to develop a database for estimating organ dose in a voxelized patient model for coronary angiography and brain perfusion CT acquisitions with any spectra and angular tube current modulation setting. The database enables organ dose estimation for existing and novel acquisition techniques without requiring Monte Carlo simulations. Methods: The study simulated transport of monoenergetic photons between 5 and 150 keV for 1000 projections over 360 Degree-Sign through anthropomorphic voxelized female chest and head (0 Degree-Sign and 30 Degree-Sign tilt) phantoms and standard head and body CTDI dosimetry cylinders. The simulations resulted in tables of normalized dose deposition for several radiosensitive organs quantifying the organ dose per emitted photon for each incident photon energy and projection angle for coronary angiography and brain perfusion acquisitions. The values in a table can be multiplied by an incident spectrum and number of photons at each projection angle and then summed across all energies and angles to estimate total organ dose. Scanner-specific organ dose may be approximated by normalizing the database-estimated organ dose by the database-estimated CTDI{sub vol} and multiplying by a physical CTDI{sub vol} measurement. Two examples are provided demonstrating how to use the tables to estimate relative organ dose. In the first, the change in breast and lung dose during coronary angiography CT scans is calculated for reduced kVp, angular tube current modulation, and partial angle scanning protocols relative to a reference protocol. In the second example, the change in dose to the eye lens is calculated for a brain perfusion CT acquisition in which the gantry is tilted 30 Degree-Sign relative to a nontilted scan. Results: Our database provides tables of normalized dose deposition for several radiosensitive organs irradiated during coronary angiography and brain perfusion CT scans. Validation results indicate

  14. Ex vivo lung perfusion to improve donor lung function and increase the number of organs available for transplantation.

    PubMed

    Valenza, Franco; Rosso, Lorenzo; Coppola, Silvia; Froio, Sara; Palleschi, Alessandro; Tosi, Davide; Mendogni, Paolo; Salice, Valentina; Ruggeri, Giulia M; Fumagalli, Jacopo; Villa, Alessandro; Nosotti, Mario; Santambrogio, Luigi; Gattinoni, Luciano

    2014-06-01

    This paper describes the initial clinical experience of ex vivo lung perfusion (EVLP) at the Fondazione Ca' Granda in Milan between January 2011 and May 2013. EVLP was considered if donor PaO2 /FiO2 was below 300 mmHg or if lung function was doubtful. Donors with massive lung contusion, aspiration, purulent secretions, pneumonia, or sepsis were excluded. EVLP was run with a low-flow, open atrium and low hematocrit technique. Thirty-five lung transplants from brain death donors were performed, seven of which after EVLP. EVLP donors were older (54 ± 9 years vs. 40 ± 15 years, EVLP versus Standard, P < 0.05), had lower PaO2 /FiO2 (264 ± 78 mmHg vs. 453 ± 119 mmHg, P < 0.05), and more chest X-ray abnormalities (P < 0.05). EVLP recipients were more often admitted to intensive care unit as urgent cases (57% vs. 18%, P = 0.05); lung allocation score at transplantation was higher (79 [40-84] vs. 39 [36-46], P < 0.05). After transplantation, primary graft dysfunction (PGD72 grade 3, 32% vs. 28%, EVLP versus Standard, P = 1), mortality at 30 days (0% vs. 0%, P = 1), and overall survival (71% vs. 86%, EVLP versus Standard P = 0.27) were not different between groups. EVLP enabled a 20% increase in available donor organs and resulted in successful transplants with lungs that would have otherwise been rejected (ClinicalTrials.gov number: NCT01967953).

  15. Ex vivo lung perfusion to improve donor lung function and increase the number of organs available for transplantation

    PubMed Central

    Valenza, Franco; Rosso, Lorenzo; Coppola, Silvia; Froio, Sara; Palleschi, Alessandro; Tosi, Davide; Mendogni, Paolo; Salice, Valentina; Ruggeri, Giulia M; Fumagalli, Jacopo; Villa, Alessandro; Nosotti, Mario; Santambrogio, Luigi; Gattinoni, Luciano

    2014-01-01

    This paper describes the initial clinical experience of ex vivo lung perfusion (EVLP) at the Fondazione Ca’ Granda in Milan between January 2011 and May 2013. EVLP was considered if donor PaO2/FiO2 was below 300 mmHg or if lung function was doubtful. Donors with massive lung contusion, aspiration, purulent secretions, pneumonia, or sepsis were excluded. EVLP was run with a low-flow, open atrium and low hematocrit technique. Thirty-five lung transplants from brain death donors were performed, seven of which after EVLP. EVLP donors were older (54 ± 9 years vs. 40 ± 15 years, EVLP versus Standard, P < 0.05), had lower PaO2/FiO2 (264 ± 78 mmHg vs. 453 ± 119 mmHg, P < 0.05), and more chest X-ray abnormalities (P < 0.05). EVLP recipients were more often admitted to intensive care unit as urgent cases (57% vs. 18%, P = 0.05); lung allocation score at transplantation was higher (79 [40–84] vs. 39 [36–46], P < 0.05). After transplantation, primary graft dysfunction (PGD72 grade 3, 32% vs. 28%, EVLP versus Standard, P = 1), mortality at 30 days (0% vs. 0%, P = 1), and overall survival (71% vs. 86%, EVLP versus Standard P = 0.27) were not different between groups. EVLP enabled a 20% increase in available donor organs and resulted in successful transplants with lungs that would have otherwise been rejected (ClinicalTrials.gov number: NCT01967953). PMID:24628890

  16. Oxygen toxicity in the perfused rat liver and lung under hyperbaric conditions.

    PubMed Central

    Nishiki, K; Jamieson, D; Oshino, N; Chance, B

    1976-01-01

    1. In the lung and liver of tocopherol-deficient rats, the activities of glutathione peroxidase and glucose 6-phosphate dehydrogenase were increased substantially, suggesting an important role for both enzymes in protecting the organ against the deleterious effects of lipid peroxides. 2. Facilitation of the glutathione peroxidase reaction by infusing t-butyl hydroperoxide caused the oxidation of nicotinamide nucleotides and glutathione, resulting in a concomitant increase in the rate of release of oxidized glutathione into the perfusate. Thus the rate of production of lipid peroxide and H2O2 in the perfused organ could be compared by simultaneous measurement of the rate of glutathione release and the turnover number of the catalase reaction. 3. On hyperbaric oxygenation at 4 X 10(5)Pa, H2O2 production, estimated from the turnover of the catalase reaction, was increased slightly in the liver, and glutathione release was increased slightly, in both lung and liver. 4. Tocopherol deficiency caused a marked increase in lipid-peroxide formation as indicated by a corresponding increase in glutathione release under hyperbaric oxygenation, with a further enhancement when the tocopherol-deficient rats were also starved. 5. The study demonstrates that the primary response to hyperbaric oxygenation is an elevation of the rate of lipid peroxidation rather than of the rate of formation of H2O2 or superoxide. PMID:12754

  17. Clinical usefulness of combined radionuclide venography (RNV) and pulmonary perfusion scanning in thromboembolic disease

    SciTech Connect

    Dibos, P.E.; Park, B.J.; Luger, R.C.

    1985-05-01

    Radionuclide venography of the lower extremities and the pelvis (RNV) was performed in 1,089 patients with suspected deep venous thrombosis (INT) during the period February 1978 to December 1984. Sequential images of the calves, knees, thighs and pelvis were obtained immediately after injection of 2 mCi of Tc-99m MAA into a vein of the dorsum of each foot while tourniquets were applied above the ankles. Views of the same regions were obtained after releasing of the tourniquets. Six view pulmonary perfusion scanning (PPS) was performed routinely upon completion of RNV. Xe-133 pulmonary ventilation scans (PVS) were done just prior to RNV in patients suspected of having pulmonary embolism. Conventional radiographic venography (XRV) was obtained in 57 of the 1,089 patients; in most of these cases, XRV was carried out within 48 hours of RVV. Results of RNV and XRV were in agreement in 88% of the cases and conflicted in 12% of the 57 cases. DVT was diagnosed by RNV and XRV in 21 of the 57 patients who had both studies. RNV and XRV were normal in 29 of the 57 patients and conflicting results were obtained in 7 patients. There were 5 false-positive RNV (8.7%) and 2 false-negative RNV (3.5%) considering the XRV as the definitive study. Out of 260 patients scanned during 1984, 26 (10%) patients had RNV/PPS findings positive for DVT and pulmonary embolism (PE); in most of these cases (22) PE was clinically unsuspected. The authors conclude that RNV is a simple, safe, clinically useful technique in the evaluation of patients with suspected DVT. PPS should follow RNV routinely. The incidence of unsuspected PE in patients with DVT is high.

  18. Prospective prediction of post-radiation therapy lung function using quantitative lung scans and pulmonary function testing

    SciTech Connect

    Rubenstein, J.H.; Richter, M.P.; Moldofsky, P.J.; Solin, L.J.

    1988-07-01

    Surgeons have made use of quantitative perfusion lung scanning (QS) and forced expiratory volume in one second (FEV1) to predict a patient's ability to tolerate lung resection. In this study QS and FEV1 were used to predict prospectively pulmonary function following lung irradiation (XRT). Twenty-two patients have had QS and FEV1 determined before XRT and at planned intervals post-XRT. Serial determination of lung function post-XRT allows comment on the temporal nature of the XRT effect on lung function. Seventeen patients had QS and FEV1 determined at an interval of 2-6 months post-irradiation with a drop in the groups mean FEV1 from 1.91 to 1.87L. or 2% during that interval. In the interval from 6-12 months post-XRT, 13 patients had studies with the groups mean FEV1 dropping from 1.79 to 1.58L or 12% of the original. In the interval from 12-18 months, 6 patients had a decline in mean FEV1 from 1.73 to 1.56L. or 10% of the original. In 22 patients a predicted final FEV1 was compared with a measured value at an interval from XRT. Fourteen of these determinations were at intervals greater than 6 months from the start of XRT and 6 at intervals of greater than 1 year. FEV1 was seen to drop during the follow-up intervals toward the predicted value. In only 2 patients did the final FEV1 drop below the predicted FEV1 and never by more than 0.12L. (6%). In summary, a method for predicting post-XRT pulmonary function using QS and FEV1 is described. Serial follow-up revealed a latent period followed by a late phase where FEV1 fell toward, but not significantly below, the predicted value. Such a determination can be of value in formulating a treatment plan for patients with significantly diminished pulmonary function.

  19. TIPS bilateral noise reduction in 4D CT perfusion scans produces high-quality cerebral blood flow maps

    NASA Astrophysics Data System (ADS)

    Mendrik, Adriënne M.; Vonken, Evert-jan; van Ginneken, Bram; de Jong, Hugo W.; Riordan, Alan; van Seeters, Tom; Smit, Ewoud J.; Viergever, Max A.; Prokop, Mathias

    2011-07-01

    Cerebral computed tomography perfusion (CTP) scans are acquired to detect areas of abnormal perfusion in patients with cerebrovascular diseases. These 4D CTP scans consist of multiple sequential 3D CT scans over time. Therefore, to reduce radiation exposure to the patient, the amount of x-ray radiation that can be used per sequential scan is limited, which results in a high level of noise. To detect areas of abnormal perfusion, perfusion parameters are derived from the CTP data, such as the cerebral blood flow (CBF). Algorithms to determine perfusion parameters, especially singular value decomposition, are very sensitive to noise. Therefore, noise reduction is an important preprocessing step for CTP analysis. In this paper, we propose a time-intensity profile similarity (TIPS) bilateral filter to reduce noise in 4D CTP scans, while preserving the time-intensity profiles (fourth dimension) that are essential for determining the perfusion parameters. The proposed TIPS bilateral filter is compared to standard Gaussian filtering, and 4D and 3D (applied separately to each sequential scan) bilateral filtering on both phantom and patient data. Results on the phantom data show that the TIPS bilateral filter is best able to approach the ground truth (noise-free phantom), compared to the other filtering methods (lowest root mean square error). An observer study is performed using CBF maps derived from fifteen CTP scans of acute stroke patients filtered with standard Gaussian, 3D, 4D and TIPS bilateral filtering. These CBF maps were blindly presented to two observers that indicated which map they preferred for (1) gray/white matter differentiation, (2) detectability of infarcted area and (3) overall image quality. Based on these results, the TIPS bilateral filter ranked best and its CBF maps were scored to have the best overall image quality in 100% of the cases by both observers. Furthermore, quantitative CBF and cerebral blood volume values in both the phantom and the

  20. Acid rain: effects on arachidonic acid metabolism in perfused and ventilated guinea-pig lung.

    PubMed

    Preziosi, P; Ciabattoni, G

    1987-11-01

    Isolated, perfused and ventilated guinea-pig lungs were exposed for 10 min to acid (sulphuric + nitric acid) aerosol mimicking acid rain at pH 4.5 or 2.5, as well as to a control distilled water aerosol (pH 6.0-6.5). Lung perfusing solution was recovered and thromboxane (TX) B2 and leukotriene (LT) B4 were measured by radioimmunoassay (RIA) techniques. In a series of experiments TXB2 release averaged 0.43 +/- 0.18 (+/- SD) ng/min during exposure to distilled water aerosol and increased to 0.70 +/- 0.30 ng/min during exposure to acid aerosol at pH 4.5 (P less than 0.05). In a second series of experiments TXB2 release was 0.46 +/- 0.18 ng/min and increased to 1.07 +/- 0.51 ng/min (P less than 0.01) after acid aerosol at pH 2.5. In both cases LTB4 release, reflecting lipoxygenase activity, was unchanged. LTC4 levels were not measurable under basal conditions as well as after exposure to acid aerosol. A pneumoconstriction was also observed, being more pronounced after acid aerosol at pH 2.5. Individual sulphuric and nitric acid aerosol component solutions at pH 2.5 evoked TXB2 and airway resistance changes corresponding to those observed with the mixed acid aerosol. LTB4 was not modified. Acid rain inhalation may directly stimulate pathways leading to the bronchoconstrictor and pro-aggregating TXA2 synthesis in isolated guinea-pig lung, without affecting the lipoxygenase pathway of arachidonic acid metabolism.

  1. Changes in cortical microvasculature during misery perfusion measured by two-photon laser scanning microscopy.

    PubMed

    Tajima, Yosuke; Takuwa, Hiroyuki; Kokuryo, Daisuke; Kawaguchi, Hiroshi; Seki, Chie; Masamoto, Kazuto; Ikoma, Yoko; Taniguchi, Junko; Aoki, Ichio; Tomita, Yutaka; Suzuki, Norihiro; Kanno, Iwao; Saeki, Naokatsu; Ito, Hiroshi

    2014-08-01

    This study aimed to examine the cortical microvessel diameter response to hypercapnia in misery perfusion using two-photon laser scanning microscopy (TPLSM). We evaluated whether the vascular response to hypercapnia could represent the cerebrovascular reserve. Cerebral blood flow (CBF) during normocapnia and hypercapnia was measured by laser-Doppler flowmetry through cranial windows in awake C57/BL6 mice before and at 1, 7, 14, and 28 days after unilateral common carotid artery occlusion (UCCAO). Diameters of the cortical microvessels during normocapnia and hypercapnia were also measured by TPLSM. Cerebral blood flow and the vascular response to hypercapnia were decreased after UCCAO. Before UCCAO, vasodilation during hypercapnia was found primarily in arterioles (22.9%±3.5%). At 14 days after UCCAO, arterioles, capillaries, and venules were autoregulatorily dilated by 79.5%±19.7%, 57.2%±32.3%, and 32.0%±10.8%, respectively. At the same time, the diameter response to hypercapnia in arterioles was significantly decreased to 1.9%±1.5%. A significant negative correlation was observed between autoregulatory vasodilation and the diameter response to hypercapnia in arterioles. Our findings indicate that arterioles play main roles in both autoregulatory vasodilation and hypercapnic vasodilation, and that the vascular response to hypercapnia can be used to estimate the cerebrovascular reserve.

  2. Validation of measurements of ventilation-to-perfusion ratio inequality in the lung from expired gas

    NASA Technical Reports Server (NTRS)

    Prisk, G. Kim; Guy, Harold J B.; West, John B.; Reed, James W.

    2003-01-01

    The analysis of the gas in a single expirate has long been used to estimate the degree of ventilation-perfusion (Va/Q) inequality in the lung. To further validate this estimate, we examined three measures of Va/Q inhomogeneity calculated from a single full exhalation in nine anesthetized mongrel dogs under control conditions and after exposure to aerosolized methacholine. These measurements were then compared with arterial blood gases and with measurements of Va/Q inhomogeneity obtained using the multiple inert gas elimination technique. The slope of the instantaneous respiratory exchange ratio (R slope) vs. expired volume was poorly correlated with independent measures, probably because of the curvilinear nature of the relationship due to continuing gas exchange. When R was converted to the intrabreath Va/Q (iV/Q), the best index was the slope of iV/Q vs. volume over phase III (iV/Q slope). This was strongly correlated with independent measures, especially those relating to inhomogeneity of perfusion. The correlations for iV/Q slope and R slope considerably improved when only the first half of phase III was considered. We conclude that a useful noninvasive measurement of Va/Q inhomogeneity can be derived from the intrabreath respiratory exchange ratio.

  3. Novel Flurometric Tool to Assess Mitochondrial Redox State of Isolated Perfused Rat Lungs After Exposure to Hyperoxia

    PubMed Central

    Audi, Said H.; Staniszewski, Kevin S.; Haworth, Steven T.; Jacobs, Elizabeth R.; Ranji, Mahsa; Zablocki, Clement J.

    2013-01-01

    Recently, we demonstrated the utility of optical fluorometry to detect a change in the redox status of mitochondrial autofluorescent coenzymes nicotinamide adenine dinucleotide (NADH) and oxidized form of flavin adenine dinucleotide \\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}$({\\rm FADH}_{2})$\\end{document} (FAD), as a measure of mitochondrial function in isolated perfused rat lungs (IPL). The objective of this paper was to utilize optical fluorometry to evaluate the effect of rat exposure to hyperoxia (\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{upgreek} \\usepackage{mathrsfs} \\setlength{\\oddsidemargin}{-69pt} \\begin{document} }{}${>}{95\\%}~{\\rm O}_{2}$\\end{document} for 48 h) on lung tissue mitochondrial redox status of NADH and FAD in a nondestructive manner in IPL. Surface NADH and FAD signals were measured before and after lung perfusion with perfusate containing rotenone (ROT, complex I inhibitor), potassium cyanide (KCN, complex IV inhibitor), and/or pentachlorophenol (PCP, uncoupler). ROT- or KCN-induced increase in NADH signal is considered a measure of complex I activity, and KCN-induced decrease in FAD signal is considered a measure of complex II activity. The results show that hyperoxia decreased complex I and II activities by 63% and 55%, respectively, when compared to lungs of rats exposed to room air (normoxic rats). Mitochondrial complex I and II activities in lung homogenates were also lower (77% and 63%, respectively) for hyperoxic than for normoxic lungs. These results suggest that the mitochondrial matrix is more reduced in hyperoxic lungs than in normoxic lungs, and demonstrate the ability of optical fluorometry to detect a change

  4. Effects of carbon monoxide-releasing molecules on pulmonary vasoreactivity in isolated perfused lungs.

    PubMed

    Pak, Oleg; Bakr, Adel G; Gierhardt, Mareike; Albus, Julia; Strielkov, Ievgen; Kroschel, Florian; Hoeres, Timm; Hecker, Matthias; Ghofrani, Hossein A; Seeger, Werner; Weissmann, Norbert; Sommer, Natascha

    2016-01-15

    In addition to its renowned poisonous effects, carbon monoxide (CO) is being recognized for its beneficial actions on inflammatory and vasoregulatory pathways, particularly when applied at low concentrations via CO-releasing molecules (CO-RMs). In the lung, CO gas and CO-RMs are suggested to decrease pulmonary vascular tone and hypoxic pulmonary vasoconstriction (HPV). However, the direct effect of CO-RMs on the pulmonary vasoreactivity in isolated lungs has not yet been investigated. We assessed the effect of CORM-2 and CORM-3 on the pulmonary vasculature during normoxia and acute hypoxia (1% oxygen for 10 min) in isolated ventilated and perfused mouse lungs. The effects were compared with those of inhaled CO gas (10%). The interaction of CORM-2 or CO with cytochrome P-450 (CYP) was measured simultaneously by tissue spectrophotometry. Inhaled CO decreased HPV and vasoconstriction induced by the thromboxane mimetic U-46619 but did not alter KCl-induced vasoconstriction. In contrast, concentrations of CORM-2 and CORM-3 used to elicit beneficial effects on the systemic circulation did not affect pulmonary vascular tone. High concentration of CO-RMs or long-term application induced a continuous increase in normoxic pressure. Inhaled CO showed spectral alterations correlating with the inhibition of CYP. In contrast, during application of CORM-2 spectrophotometric signs of interaction with CYP could not be detected. Application of CO-RMs in therapeutic doses in isolated lungs neither decreases pulmonary vascular tone and HPV nor does it induce spectral alterations that are characteristic of CO-inhibited CYP. High doses, however, may cause pulmonary vasoconstriction. PMID:26586910

  5. Effects of carbon monoxide-releasing molecules on pulmonary vasoreactivity in isolated perfused lungs.

    PubMed

    Pak, Oleg; Bakr, Adel G; Gierhardt, Mareike; Albus, Julia; Strielkov, Ievgen; Kroschel, Florian; Hoeres, Timm; Hecker, Matthias; Ghofrani, Hossein A; Seeger, Werner; Weissmann, Norbert; Sommer, Natascha

    2016-01-15

    In addition to its renowned poisonous effects, carbon monoxide (CO) is being recognized for its beneficial actions on inflammatory and vasoregulatory pathways, particularly when applied at low concentrations via CO-releasing molecules (CO-RMs). In the lung, CO gas and CO-RMs are suggested to decrease pulmonary vascular tone and hypoxic pulmonary vasoconstriction (HPV). However, the direct effect of CO-RMs on the pulmonary vasoreactivity in isolated lungs has not yet been investigated. We assessed the effect of CORM-2 and CORM-3 on the pulmonary vasculature during normoxia and acute hypoxia (1% oxygen for 10 min) in isolated ventilated and perfused mouse lungs. The effects were compared with those of inhaled CO gas (10%). The interaction of CORM-2 or CO with cytochrome P-450 (CYP) was measured simultaneously by tissue spectrophotometry. Inhaled CO decreased HPV and vasoconstriction induced by the thromboxane mimetic U-46619 but did not alter KCl-induced vasoconstriction. In contrast, concentrations of CORM-2 and CORM-3 used to elicit beneficial effects on the systemic circulation did not affect pulmonary vascular tone. High concentration of CO-RMs or long-term application induced a continuous increase in normoxic pressure. Inhaled CO showed spectral alterations correlating with the inhibition of CYP. In contrast, during application of CORM-2 spectrophotometric signs of interaction with CYP could not be detected. Application of CO-RMs in therapeutic doses in isolated lungs neither decreases pulmonary vascular tone and HPV nor does it induce spectral alterations that are characteristic of CO-inhibited CYP. High doses, however, may cause pulmonary vasoconstriction.

  6. Morphological changes in the isolated rat liver perfused in a non-recirculating system: scanning and transmission electron microscopy.

    PubMed

    al-Ali, S Y; Hassan, I M; al-Zuhair, A G

    1987-07-01

    Isolated perfused rat livers have been used for various studies, but detailed investigation into the structural integrity of hepatocytes of this system is lacking. In this study, isolated rat livers were perfused in vitro with oxygenated Krebs-Ringer bicarbonate buffer solution, for 2 minutes and 1, 2, 3, and 4 hour(s) at 37 degrees C, using a non-recirculating perfusion system. The perfused livers were processed for semithin section light microscopy, transmission electron microscopy, and scanning electron microscopy. Sectional areas of cell deaths were measured by a camera-tracing assembly from 1.5 microns thick Araldite sections stained with toluidine blue. Progressive nuclear and cytoplasmic changes, leading to cell death, occurred in the hepatocytes of the centrilobular zone, during the 2nd, 3rd, and 4th hour of the perfusion at a rate of 9.03% +/- 1.5%, 38.7% +/- 2.7%, and 55.1% +/- 5.9% (mean +/- standard deviation) of the total sectional areas respectively. Midzonal hepatocytes showed normal basophilic staining but exhibited loss of glycogen granules, loss of microvilli, development of aqueous vacuoles and formation of blebs. The fine structures of cell organelles, glycogen granules, microvilli and plasma membrane of the cells in the periportal zone were well preserved throughout the experimental period. For further quantitative, metabolic and functional studies using isolated rat liver perfused with Krebs-Ringer solution, it is evident from the present investigation that the periportal zone represents the functional region of the hepatic lobule. Whilst progressive changes, leading to cell death, occurred in the centrilobular zone.

  7. Immunohistochemical quantitation of three collagen isotypes in perfused areas and nonperfused foci of the lungs of irradiated mice

    SciTech Connect

    Miller, G.G.; Sharplin, J.; Franko, A.J. )

    1989-07-01

    Collagen isotypes I, III, and IV were quantitated by video image analysis of fluorescent-antibody-stained lung tissue sections from control and irradiated C57L/J and BALB/c mice. The perfusion status of lungs was determined by injecting colloidal carbon into the hepatic vein immediately prior to sacrificing the animals. Well-perfused parenchymal regions turned black, whereas nonperfused areas remained pale. Previous histological studies indicated substantial differences in the types of lesions found in the lungs of these two strains. C57L/J mice develop extensive and persistent contracted fibrosis. In lung sections of C57L/J mice examined 28 weeks after a dose of 11 Gy X rays, all three collagen isotypes were significantly elevated to levels 37-51% higher than age-matched control values in perfused regions of lung. In nonperfused areas, which had the histological appearance of contracted scar tissue, the three collagen isotype levels were further elevated to values 83-90% greater than controls. This finding suggests that in C57L/J mice, an elevation of each or all of the three collagen isotypes to levels approximately 45% greater than controls is consistent with continued pulmonary function during the intermediate phase of lung damage, whereas areas of parenchyma containing isotype levels in excess of 185% of control values coincide with functionally deficient regions. BALB/cCr Alt. mice examined 28 weeks subsequent to 14.5 Gy X rays had a variety of visible lesion, most of which were nonperfused. In addition, one-quarter of nonperfused acini had no visible lesion. In perfused areas, the three isotypes were increased to 119-132% of control levels, with a further, significant (P less than 0.05) increase to 128-144% of control values in nonperfused parenchyma.

  8. Solubilized xenon 133 lung scintigraphy

    SciTech Connect

    Oates, E.; Sarno, R.C.

    1988-11-01

    Lung scanning using solubilized xenon 133 can provide important information concerning both pulmonary perfusion and ventilation. This technique proved valuable in establishing the diagnosis of congenital lobar emphysema in a 7-month-old baby.

  9. Method of Isolated Ex Vivo Lung Perfusion in a Rat Model: Lessons Learned from Developing a Rat EVLP Program

    PubMed Central

    Nelson, Kevin; Bobba, Christopher; Eren, Emre; Spata, Tyler; Tadres, Malak; Hayes,, Don; Black, Sylvester M.

    2015-01-01

    The number of acceptable donor lungs available for lung transplantation is severely limited due to poor quality. Ex-Vivo Lung Perfusion (EVLP) has allowed lung transplantation in humans to become more readily available by enabling the ability to assess organs and expand the donor pool. As this technology expands and improves, the ability to potentially evaluate and improve the quality of substandard lungs prior to transplant is a critical need. In order to more rigorously evaluate these approaches, a reproducible animal model needs to be established that would allow for testing of improved techniques and management of the donated lungs as well as to the lung-transplant recipient. In addition, an EVLP animal model of associated pathologies, e.g., ventilation induced lung injury (VILI), would provide a novel method to evaluate treatments for these pathologies. Here, we describe the development of a rat EVLP lung program and refinements to this method that allow for a reproducible model for future expansion. We also describe the application of this EVLP system to model VILI in rat lungs. The goal is to provide the research community with key information and “pearls of wisdom”/techniques that arose from trial and error and are critical to establishing an EVLP system that is robust and reproducible. PMID:25741794

  10. Ex Vivo Rehabilitation of Non-Heart-Beating Donor Lungs in a Preclinical Porcine Model: Delayed Perfusion Results in Superior Lung Function

    PubMed Central

    Mulloy, Daniel P.; Stone, Matthew L.; Crosby, Ivan K.; LaPar, Damien J.; Sharma, Ashish K.; Webb, David V.; Lau, Christine L.; Laubach, Victor E.; Kron, Irving L.

    2012-01-01

    Objectives Ex vivo lung perfusion (EVLP) is a promising modality for the evaluation and treatment of marginal donor lungs. The optimal timing of EVLP initiation and potential for rehabilitation of donor lungs with extended warm-ischemic times is unknown. This study compares the efficacy of different treatment strategies for uncontrolled non-heart-beating donor lungs. Methods Mature swine underwent hypoxic arrest followed by 60 minutes of no-touch warm-ischemia. Lungs were harvested and flushed with 4°C Perfadex®. Three groups (n=5/group) were stratified according to preservation method: cold-static preservation (CSP: 4 hrs 4°C storage), immediate EVLP (I-EVLP: 4 hrs EVLP at 37°C), and delayed EVLP (D-EVLP: 4 hrs cold storage followed by 4 hrs EVLP). EVLP groups were perfused with Steen solution™ supplemented with heparin, methylprednisolone, cefazolin, and an adenosine 2A receptor agonist. Lungs then underwent allotransplantation and four hours of recipient reperfusion prior to allograft assessment for resultant ischemia-reperfusion injury. Results Donor blood oxygenation (PO2:FiO2) prior to euthanasia was not different between groups. Oxygenation after transplantation was significantly higher in the D-EVLP group compared to the I-EVLP or CSP groups. Mean airway pressure, pulmonary artery pressure, and expression of IL-8, IL-1β, and TNF-α were all significantly reduced in the D-EVLP group. Importantly, post-transplant oxygenation exceeded acceptable clinical levels only in D-EVLP lungs. Conclusions Uncontrolled non-heart-beating donor lungs with extended warm-ischemia can be reconditioned for successful transplantation. The combination of CSP and EVLP present in the D-EVLP group was necessary to obtain optimal post-transplant function. This finding, if confirmed clinically, will allow expanded use of non-heart-beating donor lungs. PMID:22944084

  11. Quantitative gallium 67 lung scan to assess the inflammatory activity in the pneumoconioses

    SciTech Connect

    Bisson, G.; Lamoureux, G.; Begin, R.

    1987-01-01

    Gallium 67 lung scan has recently become increasingly used to evaluate the biological activity of alveolitis of interstitial lung diseases and to stage the disease process. In order to have a more precise and objective indicator of the inflammatory activity in the lung, we and others have developed computer-based quantitative techniques to process the /sup 67/Ga scan. In this report, we compare the results of three such computer-based methods of analysis of the scans of 38 normal humans and 60 patients suspected to have pneumoconiosis. Results of previous investigations on the mechanisms of /sup 67/Ga uptake in interstitial lung disease are reviewed. These data strengthen the view that quantitative /sup 67/Ga lung scan has become a standard technique to assess inflammatory activity in the interstitial lung diseases and that computer-based method of analysis of the scan provides an index of inflammatory activity of the lung disease that correlates with lung lavage and biopsy indices of inflammation in the lung tissue. 51 references.

  12. Strip sign: a new sign for diagnosis of nonembolic defects on pulmonary perfusion scintigraphy

    SciTech Connect

    Sostman, H.D.; Gottschalk, A.

    1982-03-01

    A total of 47 patients who underwent both lung ventilation-perfusion scintigraphy and pulmonary arteriography were evaluated for presence on the scintigram of perfusion defects that did not extend to the lung edge, leaving a peripheral parenchymal stripe (PPS) of perfused lung between the defect and the adjacent pleural surface. Scans were scored both with and without regard for the PPS according to probability of pulmonary embolism; these predictions were then compared with the official lung scan report given initially to the referring physician. Predictions were then verified by pulmonary arteriography. Of the 13 patients who showed one or more PPSs, four reports would have been more accurate using the revised criteria that included the stripe sign. In this study, visualization of a PPS in an area of defect on a perfusion lung scan was extremely accurate for predicting absence of pulmonary emboli in the specific area of the stripe. Further studies that would be needed to confirm this finding are discussed.

  13. EGFR kinase domain mutation positive lung cancers are sensitive to intrapleural perfusion with hyperthermic chemotherapy (IPHC) complete treatment

    PubMed Central

    Zhang, Hongjuan; Zhan, Cheng; Ke, Ji; Xue, Zhiqiang; Zhang, Aiqun; Xu, Kaifeng; Shen, Zhirong; Yu, Lei; Chen, Liang

    2016-01-01

    Lung cancer is the global leading cause of cancer-related deaths. A significant portion of lung cancer patients harbor kinase domain mutations in the epidermal growth factor receptor (EGFR). While EGFR tyrosine kinase inhibitors (TKI) effectively shrink tumors harboring mutant EGFR, clinical efficacy is limited by the development of TKI resistance. Effective alternatives are desperately needed in clinic for treating EGFR kinase domain mutation positive lung cancer. In our clinic in treating M1a lung cancer patients through intrapleural perfusion with hyperthermic chemotherapy (IPHC) followed by cycles of systemic chemotherapy (we termed this procedure IPHC complete treatment, IPHC-CT), we found dramatic tumor shrinkage in mutant EGFR-positive patients. We further confirmed the sensitivity of EGFR mutation-positive lung cancer cell lines derived from patients to HC (hyperthermic chemotherapy) treatment. We found that hyperthermia promoted accumulation of cisplatin in lung cancer cells. Hyperthermia and cisplatin synergistically downregulated the EGFR protein level, leading to quenching of signal from EGFR and induction of apoptosis. Our work therefore showed IPHC-CT is an effective treatment for EGFR kinase domain mutation positive lung cancer patients. PMID:26654941

  14. Effects of a cocarcinogen, ferric oxide, on the metabolism of benzo(a)pyrene in the isolated perfused lung

    SciTech Connect

    Warshawsky, D.; Bingham, E.

    1984-01-01

    An isolated perfused New Zealand rabbit lung preparation was used to investigate the effects of a cocarcinogen, ferric oxide (Fe/sub 2/O/sub 3/), on the metabolism of benzo(a)pyrene (BaP), a ubiquitous potent carcinogen that has been associated with the increased incidence of human bronchiogenic carcinoma in occupational and urban settings. (/sup 14/C)-BaP was administered intratracheally to an isolated perfused lung (IPL) preparation with and without Fe/sub 2/O/sub 3/ after intraperitoneal pretreatment of the whole animal with BaP or intratracheal pretreatment of the whole animal with Fe/sub 2/O/sub 3/ and/or BaP. BaP and its metabolites were isolated from serial blood samples up to 180 min after administration of (/sup 14/C)BaP to the IPL. BaP and its metabolites were also isolated from lung tissue, washout fluid, macrophage, and trachea bronchi at the end of the perfusion at 180 min. Patterns of BaP metabolites were determined by chromatographic techniques and liquid scintillation counting. Fe/sub 2/O/sub 3/ pretreatment to the whole animal or administration of Fe/sub 2/O/sub 3/ to the IPL altered BaP metabolism by the perfused lung. Fe/sub 2/O/sub 3/ pretreatment to the whole animal resulted in an increase in the total rate of appearance of metabolites of BaP in the blood, while Fe/sub 2/O/sub 3/ administration to the IPL resulted in a decrease in the total rate of appearance of BaP metabolites in the blood and inhibited the effect of pretreatment. These data suggest that pulmonary exposure to a known cocarcinogen, Fe/sub 2/O/sub 3/, in the presence of BaP results in increased production of dihydrodiols of BaP, which may be further metabolized to the ultimate carcinogenic form(s) of BaP. Therefore, Fe/sub 2/O/sub 3/ can enhance the metabolic activation of BaP by the lung, as well as act as a carrier for penetration and retention of BaP in the lung. 49 references, 6 tables.

  15. SU-F-BRF-11: Dose Rearrangement in High Dose Locally Advanced Lung Patients Based On Perfusion Imaging

    SciTech Connect

    Matrosic, C; Jarema, D; Kong, F; McShan, D; Stenmark, M; Owen, D; Ten Haken, R; Matuszak, M

    2014-06-15

    Purpose: The use of mean lung dose (MLD) limits allows individualization of lung patient tumor doses at safe levels. However, MLD does not account for local lung function differences between patients, leading to toxicity variability at the same MLD. We investigated dose rearrangement to minimize dose to functional lung, as measured by perfusion SPECT, while maintaining target coverage and conventional MLD limits. Methods: Retrospective plans were optimized for 15 locally advanced NSCLC patients enrolled in a prospective imaging trial. A priority-based optimization system was used. The baseline priorities were (1) meet OAR dose constraints, (2) maximize target gEUD, and (3) minimize physical MLD. As a final step, normal tissue doses were minimized. To determine the benefit of rearranging dose using perfusion SPECT, plans were reoptimized to minimize functional lung gEUD as the 4th priority. Results: When only minimizing physical MLD, the functional lung gEUD was 10.8+/−5.0 Gy (4.3–19.8 Gy). Only 3/15 cases showed a decrease in functional lung gEUD of ≥4% when rearranging dose to minimize functional gEUD in the cost function (10.5+/−5.0 Gy range 4.3−19.7). Although OAR constraints were respected, the dose rearrangement resulted in ≥10% increases in gEUD to an OAR in 4/15 cases. Only slight reductions in functional lung gEUD were noted when omitting the minimization of physical MLD, suggesting that constraining the target gEUD minimizes the potential to redistribute dose. Conclusion: Prioritydriven optimization permits the generation of plans that respect traditional OAR limits and target coverage, but with the ability to rearrange dose based on functional imaging. The latter appears to be limited due to the decreased solution space when constraining target coverage. Since dose rearrangement may increase dose to other OARs, it is also worthwhile to investigate global biomarkers of lung toxicity to further individualize treatment in this population

  16. What to do when a smoker's CT scan is "normal"?: Implications for lung cancer screening.

    PubMed

    Zurawska, Joanna H; Jen, Rachel; Lam, Stephen; Coxson, Harvey O; Leipsic, Jonathon; Sin, Don D

    2012-05-01

    Lung cancer is the leading cause of cancer-related mortality in the United States and around the world. There are > 90 million current and ex-smokers in the United States who are at increased risk of lung cancer. The published data from the National Lung Screening Trial (NLST) suggest that yearly screening with low-dose thoracic CT scan in heavy smokers can reduce lung cancer mortality by 20% and all-cause mortality by 7%. However, to implement this program nationwide using the NLST inclusion and exclusion criteria would be extremely expensive, with CT scan costs alone > $2 billion per annum. In this article, we offer a possible low-cost strategy to risk-stratify smokers on the basis of spirometry measurements and emphysema scoring by radiologists on CT scans. PMID:22553261

  17. Interactive lung segmentation in abnormal human and animal chest CT scans

    SciTech Connect

    Kockelkorn, Thessa T. J. P. Viergever, Max A.; Schaefer-Prokop, Cornelia M.; Bozovic, Gracijela; Muñoz-Barrutia, Arrate; Rikxoort, Eva M. van; Brown, Matthew S.; Jong, Pim A. de; Ginneken, Bram van

    2014-08-15

    Purpose: Many medical image analysis systems require segmentation of the structures of interest as a first step. For scans with gross pathology, automatic segmentation methods may fail. The authors’ aim is to develop a versatile, fast, and reliable interactive system to segment anatomical structures. In this study, this system was used for segmenting lungs in challenging thoracic computed tomography (CT) scans. Methods: In volumetric thoracic CT scans, the chest is segmented and divided into 3D volumes of interest (VOIs), containing voxels with similar densities. These VOIs are automatically labeled as either lung tissue or nonlung tissue. The automatic labeling results can be corrected using an interactive or a supervised interactive approach. When using the supervised interactive system, the user is shown the classification results per slice, whereupon he/she can adjust incorrect labels. The system is retrained continuously, taking the corrections and approvals of the user into account. In this way, the system learns to make a better distinction between lung tissue and nonlung tissue. When using the interactive framework without supervised learning, the user corrects all incorrectly labeled VOIs manually. Both interactive segmentation tools were tested on 32 volumetric CT scans of pigs, mice and humans, containing pulmonary abnormalities. Results: On average, supervised interactive lung segmentation took under 9 min of user interaction. Algorithm computing time was 2 min on average, but can easily be reduced. On average, 2.0% of all VOIs in a scan had to be relabeled. Lung segmentation using the interactive segmentation method took on average 13 min and involved relabeling 3.0% of all VOIs on average. The resulting segmentations correspond well to manual delineations of eight axial slices per scan, with an average Dice similarity coefficient of 0.933. Conclusions: The authors have developed two fast and reliable methods for interactive lung segmentation in

  18. Deep Vein Thrombosis Presenting on Pulmonary Ventilation and Perfusion Scintigraphy.

    PubMed

    Itani, Malak; Fair, Joanna; Hillman, Zachary; Behnia, Fatemeh; Elojeimy, Saeed

    2016-10-01

    A 52-year-old woman presenting with dyspnea was referred for a ventilation and perfusion scan (VQ). VQ images (with Tc-DTPA [diethylene triamine pentaacetic acid aerosol] and Tc-MAA [macroaggregated albumin]) initially appeared normal; however, count rates on perfusion images were similar to ventilation images, implying little Tc-MAA had reached the lungs. Spot images of the injected extremity demonstrated focal Tc-MAA accumulation worrisome for a venous thrombus, subsequently confirmed by Doppler ultrasound. Careful attention to relative radiotracer count rates on VQ scans is crucial to ensure diagnostic utility. In addition, abnormal low perfusion radiotracer counts may unveil other pathology with important clinical implications. PMID:27556796

  19. Immune complexes, gallium lung scans, and bronchoalveolar lavage in idiopathic interstitial pneumonitis-fibrosis

    SciTech Connect

    Gelb, A.F.; Dreisen, R.B.; Epstein, J.D.; Silverthorne, J.D.; Bickel, Y.; Fields, M.; Border, W.A.; Taylor, C.R.

    1983-08-01

    We obtained results of lung immune complexes (LIC), circulating immune complexes (CIC), 48-hour gallium lung scans (scans), bronchoalveolar lavage (BAL), and pulmonary function tests in 20 patients with idiopathic interstitial pneumonitis-fibrosis. Sixteen patients had predominantly interstitial (13 cases UIP) and/or intraalveolar (3 cases DIP) cellular disease (group 1). Prior to corticosteroid therapy in group 1, scans were positive in 75 percent, CIC were elevated in 86 percent, LIC were present in 64 percent, and BAL was abnormal in 90 percent. Duration of follow-up after treatment was 3.5 +/- 1.0 year. In group 1 after treatment with corticosteroids in 13 patients and corticosteroids and penicillamine (three patients) and plasmapheresis (one patient), only four patients remain stable or improved. After corticosteroid therapy, elevated CIC returned to normal values despite progressive patient deterioration. In three patients, lung immune complexes were still detected after circulating immune complexes had returned to normal after corticosteroid therapy. In group 2 were four patients with fibrotic disease; scans and CIC were uniformly negative, LIC were weakly present in only one patient, and BAL was abnormal in all. Despite corticosteroid therapy, all have died or deteriorated. These results suggest that positive gallium lung scans, BAL, circulating immune complexes, and to a lesser extent, lung immune complexes are associated with the cellular phase of interstitial pneumonia, but do not reliably identify a corticosteroid-responsive group.

  20. ROI for outlining an entire tumor is a reliable approach for quantification of lung cancer tumor vascular parameters using CT perfusion

    PubMed Central

    Ma, Ensen; Ren, An; Gao, Baoxiang; Yang, Minxing; Zhao, Qichao; Wang, Wu; Li, Kefeng

    2016-01-01

    Objective To investigate the effect of position and size of tumor region of interest (ROI) on the estimation of lung cancer vascular parameters using 256-slice computed tomography (CT) perfusion. Methods After institutional review board approval and written informed consent, 16 men and 11 women with lung cancer were enrolled in this CT perfusion study. Perfusion, blood volume, and peak enhancement were determined for 60 or 120 mm2 circular ROIs placed at the edge, center, and around (outlining) the visible tumor. Average values were obtained by performing ROI analysis twice by the same observers without any procedural changes. Results Perfusion, blood volume, and peak enhancement measurements were substantially higher at the edge than at the center for both 60 and 120 mm2 ROIs (all P<0.05). Measurements varied substantially depending on the ROI size. Perfusion, blood volume, and peak enhancement for the ROIs outlining tumor were intermediate between those at the tumor edge and center. There were significant correlations between median values and interquartile ranges as follows; perfusion (12.51 [7.91–28.10] mL⋅min−1⋅100 mL−1), blood volume (29.31 [21.82–37.65] mL⋅100 g−1), peak enhancement (12.93 [2.42–22.50]) for the ROIs outlining the tumor, and microvascular density ([19.43±8.78] vessels/0.74 mm2), respectively (r values were 0.732, 0.590, and 0.544 respectively, all P<0.05). Conclusion Spatial and size selection of ROI significantly affects CT perfusion analysis. ROI outlining of entire tumor provides efficient and reliable measurements for clinical assessment of lung cancer using CT perfusion. PMID:27175083

  1. Ascorbic acid prolongs the viability and stability of isolated perfused lungs: A mechanistic study using 31P and hyperpolarized 13C nuclear magnetic resonance.

    PubMed

    Shaghaghi, Hoora; Kadlecek, Stephen; Siddiqui, Sarmad; Pourfathi, Mehrdad; Hamedani, Hooman; Clapp, Justin; Profka, Harrilla; Rizi, Rahim

    2015-12-01

    Ex vivo lung perfusion (EVLP) has recently shown promise as a means of more accurately gauging the health of lung grafts and improving graft performance post-transplant. However, reperfusion of ischemic lung promotes the depletion of high-energy compounds and a progressive loss of normal mitochondrial function, and it remains unclear how and to what extent the EVLP approach contributes to this metabolic decline. Although ascorbate has been used to mitigate the effects of ischemia-reperfusion injury, the nature of its effects during EVLP are also not clear. To address these uncertainties, this study monitored the energy status of lungs during EVLP and after the administration of ascorbate using (31)P and hyperpolarized (13)C NMR (nuclear magnetic resonance). Our experiments demonstrated that the oxidative phosphorylation capacity and pyruvate dehydrogenase flux of lungs decline during ex vivo perfusion. The addition of ascorbate to the perfusate prolonged lung viability by 80% and increased the hyperpolarized (13)C bicarbonate signal by a factor of 2.7. The effect of ascorbate is apparently due not to its antioxidant quality but rather to its ability to energize cellular respiration given that it increased the lung's energy charge significantly, whereas other antioxidants (glutathione and α-lipoic acid) did not alter energy metabolism. During ascorbate administration, inhibition of mitochondrial complex I with rotenone depressed energy charge and shifted the metabolic state of the lung toward glycolysis; reenergizing the electron transport chain with TMPD (N,N,N',N'-tetramethyl-p-phenylenediamine) recovered metabolic activity. This indicates that ascorbate slows the decline of the ex vivo perfused lung's mitochondrial activity through an independent interaction with the electron transport chain complexes.

  2. Abnormal ventilation scans in middle-aged smokers. Comparison with tests of overall lung function

    SciTech Connect

    Barter, S.J.; Cunningham, D.A.; Lavender, J.P.; Gibellino, F.; Connellan, S.J.; Pride, N.B.

    1985-07-01

    The uniformity of regional ventilation during tidal breathing has been assessed using continuous inhalation of krypton-81m in 43 male, lifelong nonsmokers and 46 male, current cigarette smokers (mean daily consumption 24.1 cigarettes/day) between 44 and 61 yr of age and with mild or no respiratory symptoms. All subjects had normal chest radiographs. The results of the ventilation scans were compared with tests of overall lung function (spirometry, maximal expiratory flow-volume curves, and single-breath N2 test). Diffuse abnormalities of the ventilation scan were found in 19 (41%) of the 46 smokers but in none of the nonsmokers. Focal abnormalities were found in 7 smokers and 3 nonsmokers. Smokers showed the expected abnormalities in overall lung function (reduced FEV1 and VC, increased single-breath N2 slope, and closing volume), but in individual smokers there was only a weak relation between the severity of abnormality of overall lung function and an abnormal ventilation scan. Abnormal scans could be found when overall lung function was normal and were not invariably found when significant abnormalities in FEV1/VC or N2 slope were present. There was no relation between the presence of chronic expectoration and an abnormal scan. The prognostic significance of an abnormal ventilation scan in such smokers remains to be established.

  3. Iterative image reconstruction for cerebral perfusion CT using a pre-contrast scan induced edge-preserving prior

    NASA Astrophysics Data System (ADS)

    Ma, Jianhua; Zhang, Hua; Gao, Yang; Huang, Jing; Liang, Zhengrong; Feng, Qianjing; Chen, Wufan

    2012-11-01

    Cerebral perfusion x-ray computed tomography (PCT) imaging, which detects and characterizes the ischemic penumbra, and assesses blood-brain barrier permeability with acute stroke or chronic cerebrovascular diseases, has been developed extensively over the past decades. However, due to its sequential scan protocol, the associated radiation dose has raised significant concerns to patients. Therefore, in this study we developed an iterative image reconstruction algorithm based on the maximum a posterior (MAP) principle to yield a clinically acceptable cerebral PCT image with lower milliampere-seconds (mA s). To preserve the edges of the reconstructed image, an edge-preserving prior was designed using a normal-dose pre-contrast unenhanced scan. For simplicity, the present algorithm was termed as ‘MAP-ndiNLM’. Evaluations with the digital phantom and the simulated low-dose clinical brain PCT datasets clearly demonstrate that the MAP-ndiNLM method can achieve more significant gains than the existing FBP and MAP-Huber algorithms with better image noise reduction, low-contrast object detection and resolution preservation. More importantly, the MAP-ndiNLM method can yield more accurate kinetic enhanced details and diagnostic hemodynamic parameter maps than the MAP-Huber method.

  4. Iterative image reconstruction for cerebral perfusion CT using pre-contrast scan induced edge-preserving prior

    PubMed Central

    Ma, Jianhua; Zhang, Hua; Gao, Yang; Huang, Jing; Liang, Zhengrong; Feng, Qianjing; Chen, Wufan

    2012-01-01

    Cerebral perfusion X-ray computed tomography (PCT) imaging, which detects and characterizes the ischemic penumbra, and assesses blood-brain barrier permeability with acute stroke or chronic cerebrovascular diseases, has been developed extensively over the past decades. However, due to its sequential scan protocol, the associated radiation dose has raised significant concerns to patients. Therefore, in this study we developed an iterative image reconstruction algorithm based on the maximum a posterior (MAP) principle to yield a clinically acceptable cerebral PCT image with lower milliampere seconds (mAs). To preserve the edges of the reconstructed image, an edge-preserving prior was designed using a normal-dose pre-contrast unenhanced scan. For simplicity, the present algorithm was termed as “MAP-ndiNLM”. Evaluations with the digital phantom and the simulated low-dose clinical brain PCT datasets clearly demonstrate that the MAP-ndiNLM method can achieve more significant gains than the existing FBP and MAP-Huber algorithms with better image noise reduction, low-contrast object detection and resolution preservation. More importantly, the MAP-ndiNLM method can yield more accurate kinetic enhanced details and diagnostic hemodynamic parameter maps than the MAP-Huber method. PMID:23104003

  5. WE-G-18C-02: Estimation of Optimal B-Value Set for Obtaining Apparent Diffusion Coefficient Free From Perfusion in Non-Small Cell Lung Cancer

    SciTech Connect

    Karki, K; Hugo, G; Ford, J; Saraiya, S; Weiss, E; Olsen, K; Groves, R

    2014-06-15

    Purpose: Diffusion-weighted MRI (DW-MRI) is increasingly being investigated for radiotherapy planning and response assessment. Selection of a limited number of b-values in DW-MRI is important to keep geometrical variations low and imaging time short. We investigated various b-value sets to determine an optimal set for obtaining monoexponential apparent diffusion coefficient (ADC) close to perfusion-insensitive intravoxel incoherent motion (IVIM) model ADC (ADCIVIM) in nonsmall cell lung cancer. Methods: Seven patients had 27 DW-MRI scans before and during radiotherapy in a 1.5T scanner. Respiratory triggering was applied to the echo-planar DW-MRI with TR=4500ms approximately, TE=74ms, pixel size=1.98X1.98mm{sub 2}, slice thickness=4–6mm and 7 axial slices. Diffusion gradients were applied to all three axes producing traceweighted images with eight b-values of 0–1000μs/μm{sup 2}. Monoexponential model ADC values using various b-value sets were compared to ADCIVIM using all b-values. To compare the relative noise in ADC maps, intra-scan coefficient of variation (CV) of active tumor volumes was computed. Results: ADCIVIM, perfusion coefficient and perfusion fraction for tumor volumes were in the range of 880-1622 μm{sup 2}/s, 8119-33834 μm{sup 2}/s and 0.104–0.349, respectively. ADC values using sets of 250, 800 and 1000; 250, 650 and 1000; and 250–1000μs/μm{sup 2} only were not significantly different from ADCIVIM(p>0.05, paired t-test). Error in ADC values for 0–1000, 50–1000, 100–1000, 250–1000, 500–1000, and three b-value sets- 250, 500 and 1000; 250, 650 and 1000; and 250, 800 and 1000μs/μm{sup 2} were 15.0, 9.4, 5.6, 1.4, 11.7, 3.7, 2.0 and 0.2% relative to the reference-standard ADCIVIM, respectively. Mean intrascan CV was 20.2, 20.9, 21.9, 24.9, 32.6, 25.8, 25.4 and 24.8%, respectively, whereas that for ADCIVIM was 23.3%. Conclusion: ADC values of two 3 b-value sets

  6. Effect of vasodilators on pulmonary perfusion defects in asthma using sequential Kr-81m perfusion imaging

    SciTech Connect

    Ertle, A.R.; Tashkin, D.P.; Webber, M.M.; Soffer, M.J.; Frank, G.W.

    1984-01-01

    The investigation was undertaken to determine if vasodilator agents may enhance the diagnostic utility of perfusion lung imaging (Q) by normalizing regional perfusion abnormalities in bronchospastic patients. The effect of oxygen (02), nitroglycerine (NTG), hydralazine (H), and nifedipine (N) on regional lung perfusion defects was studied in 6 mild to severe asthmatics (ages defects was studied in 6 mild to severe asthmatics (ages 31-72yrs) using sequential Kr-81m imaging which permits repetitive imaging due to very low radiation dose and 13 sec T-1/2. Each patient was studied once weekly for 3 wks. Baseline Q scans were obtained using 10mCi of I.V. Kr-81m. the best view showing perfusion defects was used for subsequent images. At each visits, 30% 02 by ventimask was given for 20 min followed by a repeat Q scan. Subsequently, on separate visits, subjects were given either 1 dose of sublingual (sl)N 20 mg or 2 doses (1 hr between) of s1 NTG 1/150gr or po H 25mg according to a random-order crossover design. Q scans were obtained 2 min after NTG, 60 min after H, and 30 and 60 min after N. 30% 02 was given again for 20 min, and a final scan was obtained. Scan were reviewed by 2 observers and showed relatively fixed defects in 4 pts improvement in defects in 3 pts with NTG, 1 with N, 1 with H, and 2 with 02 alone. Additive effects of 02 and N or NTG were seen in 2 pts. These preliminary results suggest that vasodilators and 02 may improve regional perfusion in patients with bronchospastic disease and that this effect may be additive. These medications may thus improve the specificity of perfusion lung scanning in the diagnostic evaluation of pulmonary embolism.

  7. Quantitative assessment of emphysema from whole lung CT scans: comparison with visual grading

    NASA Astrophysics Data System (ADS)

    Keller, Brad M.; Reeves, Anthony P.; Apanosovich, Tatiyana V.; Wang, Jianwei; Yankelevitz, David F.; Henschke, Claudia I.

    2009-02-01

    Emphysema is a disease of the lungs that destroys the alveolar air sacs and induces long-term respiratory dysfunction. CT scans allow for imaging of the anatomical basis of emphysema and for visual assessment by radiologists of the extent present in the lungs. Several measures have been introduced for the quantification of the extent of disease directly from CT data in order to add to the qualitative assessments made by radiologists. In this paper we compare emphysema index, mean lung density, histogram percentiles, and the fractal dimension to visual grade in order to evaluate the predictability of radiologist visual scoring of emphysema from low-dose CT scans through quantitative scores, in order to determine which measures can be useful as surrogates for visual assessment. All measures were computed over nine divisions of the lung field (whole lung, individual lungs, and upper/middle/lower thirds of each lung) for each of 148 low-dose, whole lung scans. In addition, a visual grade of each section was also given by an expert radiologist. One-way ANOVA and multinomial logistic regression were used to determine the ability of the measures to predict visual grade from quantitative score. We found that all measures were able to distinguish between normal and severe grades (p<0.01), and between mild/moderate and all other grades (p<0.05). However, no measure was able to distinguish between mild and moderate cases. Approximately 65% prediction accuracy was achieved from using quantitative score to predict visual grade, with 73% if mild and moderate cases are considered as a single class.

  8. [Use of SPECT-scanning of the heart in estimating of influence of drugs of the background therapy of ischemic heart disease on myocardial perfusion].

    PubMed

    Svistov, A S; Sukhov, V Iu; Makiev, R G; Alanichev, A E

    2012-10-01

    Some new facts about the influence of different groups of drugs on myocardial perfusion were educed during the research. Educed facts conduce representation extension by matching the optimal therapy of ischemic heart disease. With the help of SPECT-scanning were educed myocardial blood flow, areas of maximal hypoperfusion and its influence on time pattern and redistribution of myocardial blood flow in patients receiving disease-modifying agents and statins. Some regularities of change of myocardial blood flow depending on applied group of drugs and peculiarities of influence of myocardial perfusion in certain time interval were revealed. Criteria with prognostic significance in prospective individual effectiveness of anti-ischemic drugs were pointed out. New approach, based on choice of anti-ischemic therapy depending on extent of influence on myocardial perfusion and also individual clinical and functional traits of patients, was applied. PMID:23213770

  9. Lung function in silica-exposed workers. A relationship to disease severity assessed by CT scan.

    PubMed

    Bégin, R; Ostiguy, G; Cantin, A; Bergeron, D

    1988-09-01

    To investigate the relationship of lung function, airflow limitation, and lung injury in silica-exposed workers, we analyzed the clinical, functional, and radiologic data of 94 long-term workers exposed in the granite industry or in foundries. The subjects were divided into four subsets based on chest roentgenogram and CT scan of the thorax: group 1 consisted of 21 subjects with category 0 chest roentgenogram and category 0 CT scan; group 2, 28 subjects with category E 1 on both chest roentgenogram and CT scan; group 3, 18 subjects with category E 1 on chest roentgenogram but with coalescence or conglomeration or both seen only on CT scan; and group 4, 27 subjects with category E 1 and coalescence or conglomeration or both on roentgenogram and CT scan. The groups did not differ in terms of age, height, cigarette smoking, or years of exposure. Lung volumes were significantly reduced only in group 4 (p less than 0.05). Lung compliance, diffusion capacity, and the rest-exercise P(A-a)O2 gradient were reduced in groups 3 and 4 (p less than 0.05). Expiratory flow rates were significantly reduced in groups 2, 3, and 4, with the lowest values in group 4. The expiratory flow rates in group 3 were significantly lower in group 3 than in group 2. These results support the concept that airflow in silica-exposed workers is significantly reduced when the disease is detectable on simple chest roentgenogram; coalescence or conglomeration or both on chest roentgenogram or CT scan is associated with significant loss of lung volumes, gas exchange function, and increased airflow obstruction.

  10. Effect of CAD on radiologists' detection of lung nodules on thoracic CT scans: observer performance study

    NASA Astrophysics Data System (ADS)

    Sahiner, Berkman; Hadjiiski, Lubomir M.; Chan, Heang-Ping; Shi, Jiazheng; Cascade, Philip N.; Kazerooni, Ella A.; Zhou, Chuan; Wei, Jun; Chughtai, Aamer R.; Poopat, Chad; Song, Thomas; Nojkova, Jadranka S.; Frank, Luba; Attili, Anil

    2007-03-01

    The purpose of this study was to evaluate the effect of computer-aided diagnosis (CAD) on radiologists' performance for the detection of lung nodules on thoracic CT scans. Our computer system was designed using an independent training set of 94 CT scans in our laboratory. The data set for the observer performance study consisted of 48 CT scans. Twenty scans were collected from patient files at the University of Michigan, and 28 scans by the Lung Imaging Database Consortium (LIDC). All scans were read by multiple experienced thoracic radiologists to determine the true nodule locations, defined as any region identified by one or more expert radiologists as containing a nodule larger than 3 mm in diameter. Eighteen CT examinations were nodule-free, while the remaining 30 CT examinations contained a total of 73 nodules having a median size of 5.5 mm (range 3.0-36.4 mm). Four other study radiologists read the CT scans first without and then with CAD, and provided likelihood of nodule ratings for suspicious regions. Two of the study radiologists were fellowship trained in cardiothoracic radiology, and two were cardiothoracic radiology fellows. Freeresponse receiver-operating characteristic (FROC) curves were used to compare the two reading conditions. The computer system had a sensitivity of 79% (58/73) with an average of 4.9 marks per normal scan (88/18). Jackknife alternative FROC (JAFROC) analysis indicated that the improvement with CAD was statistically significant (p=0.03).

  11. CIDI-lung-seg: a single-click annotation tool for automatic delineation of lungs from CT scans.

    PubMed

    Mansoor, Awais; Bagci, Ulas; Foster, Brent; Xu, Ziyue; Douglas, Deborah; Solomon, Jeffrey M; Udupa, Jayaram K; Mollura, Daniel J

    2014-01-01

    Accurate and fast extraction of lung volumes from computed tomography (CT) scans remains in a great demand in the clinical environment because the available methods fail to provide a generic solution due to wide anatomical variations of lungs and existence of pathologies. Manual annotation, current gold standard, is time consuming and often subject to human bias. On the other hand, current state-of-the-art fully automated lung segmentation methods fail to make their way into the clinical practice due to their inability to efficiently incorporate human input for handling misclassifications and praxis. This paper presents a lung annotation tool for CT images that is interactive, efficient, and robust. The proposed annotation tool produces an "as accurate as possible" initial annotation based on the fuzzy-connectedness image segmentation, followed by efficient manual fixation of the initial extraction if deemed necessary by the practitioner. To provide maximum flexibility to the users, our annotation tool is supported in three major operating systems (Windows, Linux, and the Mac OS X). The quantitative results comparing our free software with commercially available lung segmentation tools show higher degree of consistency and precision of our software with a considerable potential to enhance the performance of routine clinical tasks. PMID:25570151

  12. Influence of sulfur dioxide on metabolism and distribution of benzo(a)pyrene in isolated perfused rabbit lung

    SciTech Connect

    Warshawsky, D.; Niemeier, R.; Bingham, E.

    1981-06-01

    An isolated perfused lung (IPL) preparation was used to investigate the effects of SO/sub 2/ (1 to 2 ppM) on the metabolism of benzo(a)pyrene (BaP), a ubiquitous potent carcinogen that has been associated with the increased incidence of human brochiogenic carcinoma in occupational and urban populations. (/sup 14/C)BaP, with and without crude air particulate (CAP), was administered intracheally to the IPL in conjunction with SO/sub 2/ or after pretreatment of the whole animal with SO/sub 2/. Metabolites were isolated from serial blood samples up to 3 h after the administration of (/sup 14/C)BaP to the IPL. Metabolites were also isolated from lung tissue, washout fluid, macrophage, and trachea and bronchi at the end of the perfusion at 180 min. Patterns of BaP metabolites were determined by thin-layer and high-performance liquid chromatography and liquid scintillation counting. SO/sub 2/ given in conjunction with BaP on the IPL or given to the whole animal followed by BaP on the IPL, in comparison with BaP only on the IPL, resulted in a twofold increase in the total rate of appearance of metabolites of BaP in the blood with changes in the metabolic pattern. SO/sub 2/ given in conjunction with BaP and CAP on the IPL, in comparison with BaP plus SO/sub 2/ on the IPL, resulted in a threefold decrease in the total rate of appearance of metabolites of BaP in the blood with changes in the metabolic pattern.

  13. Scanning and transmission electron microscopic study of the lung of the newt, Triturus alpestris Laur.

    PubMed

    Goniakowska-Witalińska, L

    1980-01-01

    The lungs of Triturus alpestris Laur. were investigated with the scanning and transmission electron microscopes. Dimensions of the cell bodies of pneumocytes and ciliated cells, as well as the thickness of the air-blood barrier, were determined. The lungs of the newt form two simple sacs without septa. A ciliated epithelium containing goblet cells lines the pulmonary vein and partially the pulmonary artery. The remainder of the lung surface is covered internally by respiratory epithelium consisting of one type of cell and only occasionally showing the presence of single ciliated cells. All cells, ciliated, goblet and pneumocytes, contain in their cytoplasm lamellar bodies. Multivesicular bodies and numerous vesicles of variable electron density also occur in the cytoplasm of pneumocytes. Atypical mitochondria can be found in all cell types of the lung. Fixation with addition of tannic acid reveals the surface lining film. Tubular myelin figures were not observed.

  14. The effect of exogenous substrate concentrations on true and apparent metabolism of hyperpolarized pyruvate in the isolated perfused lung.

    PubMed

    Kadlecek, Stephen; Shaghaghi, Hoora; Siddiqui, Sarmad; Profka, Harrilla; Pourfathi, Mehrdad; Rizi, Rahim

    2014-12-01

    Although relatively metabolically inactive, the lung has an important role in maintaining systemic glycolytic intermediate and cytosolic redox balance. Failure to perform this function appropriately may lead to lung disease progression, including systemic aspects of these disorders. In this study, we experimentally probe the response of the isolated, perfused organ to varying glycolytic intermediate (pyruvate and lactate) concentrations, and the effect on the apparent metabolism of hyperpolarized 1-(13)C pyruvate. Twenty-four separate conditions were studied, from sub-physiological to super-physiological concentrations of each metabolite. A three-compartment model is developed, which accurately matches the full range of experiments and includes a full account of evolution of agent concentration and polarization. The model is then refined using a series of approximations which are shown to be applicable to cases of physiological relevance, and which facilitate an intuitive understanding of the saturation and scaling behavior. Perturbations of the model assumptions are used to determine the sensitivity to input parameter estimates, and finally the model is used to examine the relationship between measurements accessible by NMR and the underlying physiological parameters of interest. Based on the observed scaling of lactate labeling with lactate and pyruvate concentrations, we conclude that the level of hyperpolarized lactate signal in the lung is primarily determined by the rate at which NAD(+) is reduced to NADH. Further, although weak dependences on other factors are predicted, the modeled NAD(+) reduction rate is largely governed by the intracellular lactate pool size. Conditions affecting the lactate pool can therefore be expected to display the highest contrast in hyperpolarized (13)C-pyruvate imaging. The work is intended to serve as a basis both to interpret the signal dynamics of hyperpolarized measurements in the normal lung and to understand the cause of

  15. Meta-analysis of the independent and cumulative effects of multiple genetic modifications on pig lung xenograft performance during ex vivo perfusion with human blood

    PubMed Central

    Harris, Donald G.; Quinn, Kevin J.; French, Beth M.; Schwartz, Evan; Kang, Elizabeth; Dahi, Siamak; Phelps, Carol J.; Ayares, David L.; Burdorf, Lars; Azimzadeh, Agnes M.; Pierson, Richard N.

    2014-01-01

    Background Genetically modified pigs are a promising potential source of lung xenografts. Ex-vivo xenoperfusion is an effective platform for testing the effect of new modifications, but typical experiments are limited by testing of a single genetic intervention and small sample sizes. The purpose of this study was to analyze the individual and aggregate effects of donor genetic modifications on porcine lung xenograft survival and injury in an extensive pig lung xenoperfusion series. Methods Data from 157 porcine lung xenoperfusion experiments using otherwise unmodified heparinized human blood were aggregated as either continuous or dichotomous variables. Lungs were wild type in 17 perfusions (11% of the study group), while 31 lungs (20% of the study group) had 1 genetic modification, 40 lungs (39%) had 2, and 47 lungs (30%) had 3 or more modifications. The primary endpoint was functional lung survival to 4 hours of perfusion. Secondary analyses evaluated previously identified markers associated with known lung xenograft injury mechanisms. In addition to comparison among all xenografts grouped by survival status, a subgroup analysis was performed of lungs incorporating the GalTKO.hCD46 genotype. Results Each increase in the number of genetic modifications was associated with additional prolongation of lung xenograft survival. Lungs that exhibited survival to 4 hours generally had reduced platelet activation and thrombin generation. GalTKO and the expression of hCD46, HO-1, hCD55 or hEPCR were associated with improved survival. hTBM, HLA-E, and hCD39 were associated with no significant effect on the primary outcome. Conclusion This meta-analysis of an extensive lung xenotransplantation series demonstrates that increasing the number of genetic modifications targeting known xenogeneic lung injury mechanisms is associated with incremental improvements in lung survival. While more detailed mechanistic studies are needed to explore the relationship between gene expression

  16. Electrical impedance tomography for assessing ventilation/perfusion mismatch for pulmonary embolism detection without interruptions in respiration.

    PubMed

    Nguyen, Doan Trang; Thiagalingam, Aravinda; Bhaskaran, Abhishek; Barry, Michael A; Pouliopoulos, Jim; Jin, Craig; McEwan, Alistair L

    2014-01-01

    Recent studies have shown high correlation between pulmonary perfusion mapping with impedance contrast enhanced Electrical Impedance Tomography (EIT) and standard perfusion imaging methods such as Computed Tomography (CT) and Single Photon Emission Computerized Tomography (SPECT). EIT has many advantages over standard imaging methods as it is highly portable and non-invasive. Contrast enhanced EIT uses hypertonic saline bolus instead of nephrotoxic contrast medium that are utilized by CT and nuclear Ventilation/Perfusion (V/Q) scans. However, current implementation of contrast enhanced EIT requires induction of an apnea period for perfusion measurement, rendering it disadvantageous compared with current gold standard imaging modalities. In the present paper, we propose the use of a wavelet denoising algorithm to separate perfusion signal from ventilation signal such that no interruption in patient's ventilation would be required. Furthermore, right lung to left lung perfusion ratio and ventilation ratio are proposed to assess the mismatch between ventilation and perfusion for detection of Pulmonary Embolism (PE). The proposed methodology was validated on an ovine model (n=3, 83.7±7.7 kg) with artificially induced PE in the right lung. The results showed a difference in right lung to left lung perfusion ratio between baseline and diseased states in all cases with all paired t-tests between baseline and PE yielding p <; 0.01, while the right lung to left lung ventilation ratio remained unchanged in two out of three experiments. Statistics were pooled from multiple repetitions of measurements per experiment.

  17. Estimation of optimal b-value sets for obtaining apparent diffusion coefficient free from perfusion in non-small cell lung cancer.

    PubMed

    Karki, Kishor; Hugo, Geoffrey D; Ford, John C; Olsen, Kathryn M; Saraiya, Siddharth; Groves, Robert; Weiss, Elisabeth

    2015-10-21

    The purpose of this study was to determine optimal sets of b-values in diffusion-weighted MRI (DW-MRI) for obtaining monoexponential apparent diffusion coefficient (ADC) close to perfusion-insensitive intravoxel incoherent motion (IVIM) model ADC (ADCIVIM) in non-small cell lung cancer. Ten subjects had 40 DW-MRI scans before and during radiotherapy in a 1.5 T MRI scanner. Respiratory triggering was applied to the echo-planar DW-MRI with TR ≈ 4500 ms, TE  =  74 ms, eight b-values of 0-1000 μs μm(-2), pixel size  =  1.98 × 1.98 mm(2), slice thickness  =  6 mm, interslice gap  =  1.2 mm, 7 axial slices and total acquisition time ≈6 min. One or more DW-MRI scans together covered the whole tumour volume. Monoexponential model ADC values using various b-value sets were compared to reference-standard ADCIVIM values using all eight b-values. Intra-scan coefficient of variation (CV) of active tumour volumes was computed to compare the relative noise in ADC maps. ADC values for one pre-treatment DW-MRI scan of each of the 10 subjects were computed using b-value pairs from DW-MRI images synthesized for b-values of 0-2000 μs μm(-2) from the estimated IVIM parametric maps and corrupted by various Rician noise levels. The square root of mean of squared error percentage (RMSE) of the ADC value relative to the corresponding ADCIVIM for the tumour volume of the scan was computed. Monoexponential ADC values for the b-value sets of 250 and 1000; 250, 500 and 1000; 250, 650 and 1000; 250, 800 and 1000; and 250-1000 μs μm(-2) were not significantly different from ADCIVIM values (p > 0.05, paired t-test). Mean error in ADC values for these sets relative to ADCIVIM were within 3.5%. Intra-scan CVs for these sets were comparable to that for ADCIVIM. The monoexponential ADC values for other sets-0-1000; 50-1000; 100-1000; 500-1000; and 250 and 800 μs μm(-2) were significantly different from the ADCIVIM values. From Rician noise

  18. Estimation of optimal b-value sets for obtaining apparent diffusion coefficient free from perfusion in non-small cell lung cancer

    NASA Astrophysics Data System (ADS)

    Karki, Kishor; Hugo, Geoffrey D.; Ford, John C.; Olsen, Kathryn M.; Saraiya, Siddharth; Groves, Robert; Weiss, Elisabeth

    2015-10-01

    The purpose of this study was to determine optimal sets of b-values in diffusion-weighted MRI (DW-MRI) for obtaining monoexponential apparent diffusion coefficient (ADC) close to perfusion-insensitive intravoxel incoherent motion (IVIM) model ADC (ADCIVIM) in non-small cell lung cancer. Ten subjects had 40 DW-MRI scans before and during radiotherapy in a 1.5 T MRI scanner. Respiratory triggering was applied to the echo-planar DW-MRI with \\text{TR}≈ 4500 ms, TE  =  74 ms, eight b-values of 0-1000 μs μm-2, pixel size  =  1.98× 1.98 mm2, slice thickness  =  6 mm, interslice gap  =  1.2 mm, 7 axial slices and total acquisition time ≈6 min. One or more DW-MRI scans together covered the whole tumour volume. Monoexponential model ADC values using various b-value sets were compared to reference-standard ADCIVIM values using all eight b-values. Intra-scan coefficient of variation (CV) of active tumour volumes was computed to compare the relative noise in ADC maps. ADC values for one pre-treatment DW-MRI scan of each of the 10 subjects were computed using b-value pairs from DW-MRI images synthesized for b-values of 0-2000 μs μm-2 from the estimated IVIM parametric maps and corrupted by various Rician noise levels. The square root of mean of squared error percentage (RMSE) of the ADC value relative to the corresponding ADCIVIM for the tumour volume of the scan was computed. Monoexponential ADC values for the b-value sets of 250 and 1000; 250, 500 and 1000; 250, 650 and 1000; 250, 800 and 1000; and 250-1000 μs μm-2 were not significantly different from ADCIVIM values (p>0.05 , paired t-test). Mean error in ADC values for these sets relative to ADCIVIM were within 3.5%. Intra-scan CVs for these sets were comparable to that for ADCIVIM. The monoexponential ADC values for other sets—0-1000 50-1000 100-1000 500-1000 and 250 and 800 μs μm-2 were significantly different from the ADCIVIM values. From Rician noise simulation

  19. Estimation of optimal b-value sets for obtaining apparent diffusion coefficient free from perfusion in non-small cell lung cancer

    PubMed Central

    Karki, Kishor; Hugo, Geoffrey D.; Ford, John C.; Olsen, Kathryn M.; Saraiya, Siddharth; Groves, Robert; Weiss, Elisabeth

    2015-01-01

    The purpose of this study was to determine optimal sets of b-values in diffusion-weighted MRI (DW-MRI) for obtaining monoexponential apparent diffusion coefficient (ADC) close to perfusion-insensitive intravoxel incoherent motion (IVIM) model ADC (ADCIVIM) in non-small cell lung cancer. Ten subjects had 40 DW-MRI scans before and during radiotherapy in a 1.5T MRI scanner. Respiratory triggering was applied to the echo-planar DW-MRI with TR ≈ 4500 ms, TE = 74 ms, eight b-values of 0–1000 µs/µm2, pixel size = 1.98×1.98 mm2, slice thickness = 6 mm, interslice gap = 1.2 mm, 7 axial slices and total acquisition time ≈ 6 min. One or more DW-MRI scans together covered the whole tumour volume. Monoexponential model ADC values using various b-value sets were compared to reference-standard ADCIVIM values using all eight b-values. Intra-scan coefficient of variation (CV) of active tumour volumes was computed to compare the relative noise in ADC maps. ADC values for one pre-treatment DW-MRI scan of each of the 10 subjects were computed using b-value pairs from DW-MRI images synthesized for b-values of 0–2000 µs/µm2 from the estimated IVIM parametric maps and corrupted by various Rician noise levels. The square root of mean of squared error percentage (RMSE) of the ADC value relative to the corresponding ADCIVIM for the tumour volume of the scan was computed. Monoexponential ADC values for the b-value sets of 250 and 1000; 250, 500 and 1000; 250, 650 and 1000; 250, 800 and 1000; and 250–1000 µs/µm2 were not significantly different from ADCIVIM values (p > 0.05, paired t-test). Mean error in ADC values for these sets relative to ADCIVIM were within 3.5%. Intra-scan CVs for these sets were comparable to that for ADCIVIM. The monoexponential ADC values for other sets- 0–1000; 50–1000; 100–1000; 500–1000; and 250 and 800 µs/µm2 were significantly different from the ADCIVIM values. From Rician noise simulation using b-value pairs, there was a wide range of

  20. A comparative analysis of the dependences of the hemodynamic parameters on changes in ROI's position in perfusion CT scans

    NASA Astrophysics Data System (ADS)

    Choi, Yong-Seok; Cho, Jae-Hwan; Namgung, Jang-Sun; Kim, Hyo-Jin; Yoon, Dae-Young; Lee, Han-Joo

    2013-05-01

    This study performed a comparative analysis of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and mean time-to-peak (TTP) obtained by changing the region of interest's (ROI) anatomical positions, during CT brain perfusion. We acquired axial source images of perfusion CT from 20 patients undergoing CT perfusion exams due to brain trauma. Subsequently, the CBV, CBF, MTT, and TTP values were calculated through data-processing of the perfusion CT images. The color scales for the CBV, CBF, MTT, and TTP maps were obtained using the image data. Anterior cerebral artery (ACA) was taken as the standard ROI for the calculations of the perfusion values. Differences in the hemodynamic average values were compared in a quantitative analysis by placing ROI and the dividing axial images into proximal, middle, and distal segments anatomically. By performing the qualitative analysis using a blind test, we observed changes in the sensory characteristics by using the color scales of the CBV, CBF, and MTT maps in the proximal, middle, and distal segments. According to the qualitative analysis, no differences were found in CBV, CBF, MTT, and TTP values of the proximal, middle, and distal segments and no changes were detected in the color scales of the the CBV, CBF, MTT, and TTP maps in the proximal, middle, and distal segments. We anticipate that the results of the study will useful in assessing brain trauma patients using by perfusion imaging.

  1. Limited value of CT brain scans in the staging of small cell lung cancer

    SciTech Connect

    Johnson, D.H.; Windham, W.W.; Allen, J.H.; Greco, F.A.

    1983-01-01

    Computed tomography of the brain was performed as part of the initial staging evaluation of 84 patients with small cell lung cancer. Brain scans indicative of metastatic disease were obtained in 12 (14%) patients, two of whom had no neurologic signs or symptoms. One of these had no other extrathoracic disease. Brainscans without evidence of metastatic disease were obtained in 72 patients, 58 (80.5%) of whom had no signs or symptoms suggestive of metastatic intracranial disease. In the 14 patients with neurologic symptoms but negative computed tomographic scans, other explanations than brain metastases were found. It was concluded that head scanning is a sensitive and accurate method of detecting central nervous system metastases in patients with small cell lung cancer. However, head computed tomography should not be included as part of the initial staging evaluation of the neurologically asymptomatic patients. In only one of 60 such patients did the brain scan change the initial clinical staging, which included chest films, liver and bone scans, and bone marrow biopsy.

  2. Ventilation-perfusion relationships in the lung during head-out water immersion

    NASA Technical Reports Server (NTRS)

    Derion, Toniann; Guy, Harold J. B.; Tsukimoto, Koichi; Schaffartzik, Walter; Prediletto, Renato; Poole, David C.; Knight, Douglas R.; Wagner, Peter D.

    1992-01-01

    Mechanisms of altered pulmonary gas exchange during water immersion were studied in 12 normal males: 6 young (aged 20-29) and 6 older (aged 40-45). It is concluded that, in young subjects with closing volume (CV) less than expiratory reserve volume (ERV), gas exchange was enhanced during immersion, because normal ventilation-perfusion relations were preserved, and by mass balance, the ventilation/O2 uptake changes elevated arterial P(O2). In older males with CV greater than ERV and 52 percent of tidal volume below CV, immersion-induced airways closure during tidal breathing was associated with minimally increased shunt that did not significantly impair gas exchange. It is suggested that airways closure of this degree is of little importance to gas exchange.

  3. Characterizing Functional Lung Heterogeneity in COPD Using Reference Equations for CT Scan-Measured Lobar Volumes

    PubMed Central

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

    2013-01-01

    Background: 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]). Methods: 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. Results: 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. Conclusions: 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. PMID:23699785

  4. Short inhalation exposures of the isolated and perfused rat lung to respirable dry particle aerosols; the detailed pharmacokinetics of budesonide, formoterol, and terbutaline.

    PubMed

    Ewing, Per; Eirefelt, Stefan J; Andersson, Paul; Blomgren, Anders; Ryrfeldt, Ake; Gerde, Per

    2008-06-01

    There is an increasing interest in using the lung as a route of entry for both local and systemic administration of drugs. However, because adequate technologies have been missing in the preclinical setting, few investigators have addressed the detailed disposition of drugs in the lung following short inhalation exposures to highly concentrated dry powder aerosols. New methods are needed to explore the disposition of drugs after short inhalation exposures, thus mimicking a future clinical use. Our aim was to study the pulmonary disposition of budesonide, formoterol, and terbutaline, which are clinically used for the treatment of bronchial asthma. Using the recently developed DustGun aerosol technology, we exposed by inhalation for approximately 1 min the isolated and perfused rat lung (IPL) to respirable dry particle aerosols of the three drugs at high concentrations. The typical aerosol concentration was 1 mug/mL, and the particle size distribution of the tested substances varied with a MMAD ranging from 2.3 to 5.3 mum. The IPL was perfused in single pass mode and repeated samples of the perfusate were taken for up to 80 min postexposure. The concentration of drug in perfusate and in lung extracts was measured using LC-MS/MS. The deposited dose was determined by adding the amounts of drug collected in perfusate to the amount extracted from the tissues at 80 min. Deposited amounts of budesonide, formoterol fumarate, and terbutaline sulphate were 23 +/- 17, 36 +/- 8, and 60 +/- 3.2 mug (mean +/- SD, n = 3), respectively. Retention in lung tissues at the end of the perfusion period expressed as fraction of deposited dose was 0.19 +/- 0.05, 0.19 +/- 0.06, and 0.04 +/- 0.01 (mean +/- SD, n = 3) for budesonide, formoterol, and terbutaline, respectively. Each short inhalation exposure to the highly concentrated aerosols consumed 1-3 mg powder. Hence, this system can be particularly useful for obtaining a detailed pharmacokinetic characterization of inhaled compounds in

  5. Abolished ventilation and perfusion of lung caused by blood clot in the left main bronchus: auto-downregulation of pulmonary arterial blood supply.

    PubMed

    Afzelius, P; Bergmann, A; Henriksen, J H

    2015-01-01

    It is generally assumed that the lungs possess arterial autoregulation associated with bronchial obstruction. A patient with pneumonia and congestive heart failure unexpectedly developed frequent haemoptysis. High-resolution CT and diagnostic CT were performed as well as ventilation/perfusion (V/Q) scintigraphy with single-photon emission CT (SPECT)/CT. V/Q SPECT/CT demonstrated abolished ventilation due to obstruction of the left main bronchus and markedly reduced perfusion of the entire left lung, a condition that was completely reversed after removal of a blood clot. We present the first pictorially documented case of hypoxia-induced pulmonary vasoconstriction and flow shift in a main pulmonary artery due to a complete intrinsic obstruction of the ipsilateral main bronchus. The condition is reversible, contingent on being relieved within a few days. PMID:26374773

  6. Depleted energy charge and increased pulmonary endothelial permeability induced by mitochondrial complex I inhibition are mitigated by coenzyme Q1 in the isolated perfused rat lung.

    PubMed

    Bongard, Robert D; Yan, Ke; Hoffmann, Raymond G; Audi, Said H; Zhang, Xiao; Lindemer, Brian J; Townsley, Mary I; Merker, Marilyn P

    2013-12-01

    Mitochondrial dysfunction is associated with various forms of lung injury and disease that also involve alterations in pulmonary endothelial permeability, but the relationship, if any, between the two is not well understood. This question was addressed by perfusing isolated intact rat lung with a buffered physiological saline solution in the absence or presence of the mitochondrial complex I inhibitor rotenone (20 μM). Compared to control, rotenone depressed whole lung tissue ATP from 5.66 ± 0.46 (SEM) to 2.34 ± 0.15 µmol · g(-1) dry lung, with concomitant increases in the ADP:ATP and AMP:ATP ratios. Rotenone also increased lung perfusate lactate (from 12.36 ± 1.64 to 38.62 ± 3.14 µmol · 15 min(-1) perfusion · g(-1) dry lung) and the lactate:pyruvate ratio, but had no detectable impact on lung tissue GSH:GSSG redox status. The amphipathic quinone coenzyme Q1 (CoQ1; 50 μM) mitigated the impact of rotenone on the adenine nucleotide balance, wherein mitigation was blocked by NAD(P)H-quinone oxidoreductase 1 or mitochondrial complex III inhibitors. In separate studies, rotenone increased the pulmonary vascular endothelial filtration coefficient (Kf) from 0.043 ± 0.010 to 0.156 ± 0.037 ml · min(-1) · cm H2O(-1) · g(-1) dry lung, and CoQ1 protected against the effect of rotenone on Kf. A second complex I inhibitor, piericidin A, qualitatively reproduced the impact of rotenone on Kf and the lactate:pyruvate ratio. Taken together, the observations imply that pulmonary endothelial barrier integrity depends on mitochondrial bioenergetics as reflected in lung tissue ATP levels and that compensatory activation of whole lung glycolysis cannot protect against pulmonary endothelial hyperpermeability in response to mitochondrial blockade. The study further suggests that low-molecular-weight amphipathic quinones may have therapeutic utility in protecting lung barrier function in mitochondrial insufficiency.

  7. Depleted energy charge and increased pulmonary endothelial permeability induced by mitochondrial complex I inhibition are mitigated by coenzyme Q1 in the isolated perfused rat lung

    PubMed Central

    Bongard, Robert D.; Yan, Ke; Hoffmann, Raymond G.; Audi, Said H.; Zhang, Xiao; Lindemer, Brian J.; Townsley, Mary I.; Merker, Marilyn P.

    2013-01-01

    Mitochondrial dysfunction is associated with various forms of lung injury and disease that also involve alterations in pulmonary endothelial permeability, but the relationship, if any, between the two is not well understood. This question was addressed by perfusing the isolated intact rat lung with a buffered physiological saline solution in the absence or presence of the mitochondrial complex I inhibitor rotenone (20 uM). As compared to control, rotenone depressed whole lung tissue ATP from 5.66 ± 0.46 (SEM) to 2.34 ± 0.15 (SEM) μmol·gram−1 dry lung, with concomitant increases in the ADP:ATP and AMP:ATP ratios. Rotenone also increased lung perfusate lactate (from 12.36 ± 1.64 (SEM) to 38.62 ± 3.14 μmol·15 min−1 perfusion·gm−1 dry lung) and the lactate:pyruvate ratio, but had no detectable impact on lung tissue GSH:GSSG redox status. The amphipathic quinone, coenzyme Q1 (CoQ1; 50 μM) mitigated the impact of rotenone on the adenine nucleotide balance, wherein mitigation was blocked by NAD(P)H:quinone oxidoreductase 1 (NQO1) or mitochondrial complex III inhibitors. In separate studies, rotenone increased the pulmonary vascular endothelial filtration coefficient (Kf) from 0.043 ± 0.010 (SEM) to 0.156 ± 0.037 (SEM) ml·min−1·cm H2O−1·gm−1 dry lung weight, and CoQ1 protected against the effect of rotenone on Kf. A second complex I inhibitor, piericidin A, qualitatively reproduced the impact of rotenone on Kf and the lactate/pyruvate ratio. Taken together, the observations imply that pulmonary endothelial barrier integrity depends on mitochondrial bioenergetics as reflected in lung tissue ATP levels and that compensatory activation of whole lung glycolysis cannot protect against pulmonary endothelial hyperpermeability in response to mitochondrial blockade. The study further suggests that low molecular weight amphipathic quinones may have therapeutic utility in protecting lung barrier function in mitochondrial insufficiency. PMID:23912160

  8. Bilateral basal Xe-133 retention and ventilation/perfusion patterns in mild and subclinical congestive heart failure

    SciTech Connect

    Lee, H.K.; Skarzynski, J.J.; Spadaro, A. )

    1989-12-01

    The Xe-133 ventilation pattern in congestive heart failure (CHF) was assessed using 24 inpatient ventilation/perfusion studies performed to rule out pulmonary embolism. Patients with histories of CHF, myocardial infarction (MI), and cardiomyopathy were included in the study. Frank pulmonary edema, pulmonary embolism, and other known lung diseases such as chronic obstructive lung disease, tumor, and pneumonia were excluded. Fifteen of the 24 patients had abnormal ventilation scans. Twelve of the 15 showed bilateral basal Xe-133 retention on washout; the remaining 3 showed diffuse, posterior regional retention. On perfusion scans, 14 of the 15 abnormal ventilation patients showed evidence of CHF such as inverted perfusion gradient, enlarged cardiac silhouette, or patchy perfusion, and all of them had a history of CHF or cardiac disease. Nine of the 24 patients had normal ventilation scans, including normal washout patterns. Seven of the nine had normal perfusion (p less than 0.01). Four of the nine normal ventilation patients had a history of cardiac disease or CHF but no recent acute MI. Bilateral basal regional Xe-133 retention, coupled with perfusion scan evidence of CHF such as inverted perfusion gradient, enlarged cardiac silhouette, and patchy perfusion pattern, appears to be a sensitive and characteristic ventilation/perfusion finding in mild or subclinical CHF.

  9. Ventilation-perfusion inequality in the human lung is not increased following no-decompression-stop hyperbaric exposure.

    PubMed

    Moore, Gaea Schwaebe; Wong, Stewart C; Darquenne, Chantal; Neuman, Tom S; West, John B; Kim Prisk, G

    2009-11-01

    Venous gas bubbles occur in recreational SCUBA divers in the absence of decompression sickness, forming venous gas emboli (VGE) which are trapped within pulmonary circulation and cleared by the lung without overt pathology. We hypothesized that asymptomatic VGE would transiently increase ventilation-perfusion mismatch due to their occlusive effects within the pulmonary circulation. Two sets of healthy volunteers (n = 11, n = 12) were recruited to test this hypothesis with a single recreational ocean dive or a baro-equivalent dry hyperbaric dive. Pulmonary studies (intrabreath V (A)/Q (iV/Q), alveolar dead space, and FVC) were conducted at baseline and repeat 1- and 24-h after the exposure. Contrary to our hypothesis V (A)/Q mismatch was decreased 1-h post-SCUBA dive (iV/Q slope 0.023 +/- 0.008 ml(-1) at baseline vs. 0.010 +/- 0.005 NS), and was significantly reduced 24-h post-SCUBA dive (0.000 +/- 0.005, p < 0.05), with improved V (A)/Q homogeneity inversely correlated to dive severity. No changes in V (A)/Q mismatch were observed after the chamber dive. Alveolar dead space decreased 24-h post-SCUBA dive (78 +/- 10 ml at baseline vs. 56 +/- 5, p < 0.05), but not 1-h post dive. FVC rose 1-h post-SCUBA dive (5.01 +/- 0.18 l vs. 5.21 +/- 0.26, p < 0.05), remained elevated 24-h post SCUBA dive (5.06 +/- 0.2, p < 0.05), but was decreased 1-hr after the chamber dive (4.96 +/- 0.31 L to 4.87 +/- 0.32, p < 0.05). The degree of V (A)/Q mismatch in the lung was decreased following recreational ocean dives, and was unchanged following an equivalent air chamber dive, arguing against an impact of VGE on the pulmonary circulation.

  10. Variation compensation and analysis on diaphragm curvature analysis for emphysema quantification on whole lung CT scans

    NASA Astrophysics Data System (ADS)

    Keller, Brad M.; Reeves, Anthony P.; Barr, R. Graham; Yankelevitz, David F.; Henschke, Claudia I.

    2010-03-01

    CT scans allow for the quantitative evaluation of the anatomical bases of emphysema. Recently, a non-density based geometric measurement of lung diagphragm curvature has been proposed as a method for the quantification of emphysema from CT. This work analyzes variability of diaphragm curvature and evaluates the effectiveness of a compensation methodology for the reduction of this variability as compared to emphysema index. Using a dataset of 43 scan-pairs with less than a 100 day time-interval between scans, we find that the diaphragm curvature had a trend towards lower overall variability over emphysema index (95% CI:-9.7 to + 14.7 vs. -15.8 to +12.0), and that the variation of both measures was reduced after compensation. We conclude that the variation of the new measure can be considered comparable to the established measure and the compensation can reduce the apparent variation of quantitative measures successfully.

  11. Lung uptake on Tc-99m albumin colloid liver spleen scan and on Ga-67 scan in angiotropic lymphoma

    SciTech Connect

    Kacki, M.H.; Joyce, J.M.; Coupal, J.J.; Ryo, U.Y. )

    1990-03-01

    Lung uptake of Tc-99m sulfur colloid has been reported in various hepatic and extrahepatic diseases, and lung uptake of gallium-67 may occur in patients with various interstitial lung disease without radiographic abnormality. This may be the first case of Tc-99m albumin colloid and Ga-67 lung uptake in a patient with angiotropic lymphoma of the liver, spleen, and uterus.

  12. Dosimetric impact of number of treatment fields in uniform scanning proton therapy planning of lung cancer.

    PubMed

    Rana, Suresh; Simpson, Hilarie; Larson, Gary; Zheng, Yuanshui

    2014-10-01

    The main purpose of this study was to perform a treatment planning study for lung cancer comparing 2-field (2F) versus 3-field (3F) techniques in uniform scanning proton therapy (USPT). Ten clinically approved lung cancer treatment plans delivered using USPT at our proton center were included in this retrospective study. All 10 lung cases included 4D computed tomography (CT) simulation. The delineation of target volumes was done based on the maximum intensity projection (MIP) images. Both the 3F and 2F treatment plans were generated for the total dose of 74 cobalt-gray-equivalent (CGE) with a daily dose of 2 CGE. 3F plan was generated by adding an extra beam in the 2F plan. Various dosimetric parameters between 2F and 3F plans were evaluated. 3F plans produced better target coverage and conformality as well as lower mean dose to the lung, with absolute difference between 3F and 2F plans within 2%. In contrast, the addition of third beam led to increase of low-dose regions (V20 and V5) in the lung in 3F plans compared to the ones in 2F plans with absolute difference within 2%. Maximum dose to the spinal cord was lower in 2F plans. Mean dose to the heart and esophagus were comparable in both 3F and 2F plans. In conclusion, the 3F technique in USPT produced better target coverage and conformality, but increased the low-dose regions in the lung when compared to 2F technique.

  13. Dosimetric impact of number of treatment fields in uniform scanning proton therapy planning of lung cancer

    PubMed Central

    Rana, Suresh; Simpson, Hilarie; Larson, Gary; Zheng, Yuanshui

    2014-01-01

    The main purpose of this study was to perform a treatment planning study for lung cancer comparing 2-field (2F) versus 3-field (3F) techniques in uniform scanning proton therapy (USPT). Ten clinically approved lung cancer treatment plans delivered using USPT at our proton center were included in this retrospective study. All 10 lung cases included 4D computed tomography (CT) simulation. The delineation of target volumes was done based on the maximum intensity projection (MIP) images. Both the 3F and 2F treatment plans were generated for the total dose of 74 cobalt-gray-equivalent (CGE) with a daily dose of 2 CGE. 3F plan was generated by adding an extra beam in the 2F plan. Various dosimetric parameters between 2F and 3F plans were evaluated. 3F plans produced better target coverage and conformality as well as lower mean dose to the lung, with absolute difference between 3F and 2F plans within 2%. In contrast, the addition of third beam led to increase of low-dose regions (V20 and V5) in the lung in 3F plans compared to the ones in 2F plans with absolute difference within 2%. Maximum dose to the spinal cord was lower in 2F plans. Mean dose to the heart and esophagus were comparable in both 3F and 2F plans. In conclusion, the 3F technique in USPT produced better target coverage and conformality, but increased the low-dose regions in the lung when compared to 2F technique. PMID:25525308

  14. The gravitational distribution of ventilation-perfusion ratio is more uniform in prone than supine posture in the normal human lung.

    PubMed

    Henderson, A Cortney; Sá, Rui Carlos; Theilmann, Rebecca J; Buxton, Richard B; Prisk, G Kim; Hopkins, Susan R

    2013-08-01

    The gravitational gradient of intrapleural pressure is suggested to be less in prone posture than supine. Thus the gravitational distribution of ventilation is expected to be more uniform prone, potentially affecting regional ventilation-perfusion (Va/Q) ratio. Using a novel functional lung magnetic resonance imaging technique to measure regional Va/Q ratio, the gravitational gradients in proton density, ventilation, perfusion, and Va/Q ratio were measured in prone and supine posture. Data were acquired in seven healthy subjects in a single sagittal slice of the right lung at functional residual capacity. Regional specific ventilation images quantified using specific ventilation imaging and proton density images obtained using a fast gradient-echo sequence were registered and smoothed to calculate regional alveolar ventilation. Perfusion was measured using arterial spin labeling. Ventilation (ml·min(-1)·ml(-1)) images were combined on a voxel-by-voxel basis with smoothed perfusion (ml·min(-1)·ml(-1)) images to obtain regional Va/Q ratio. Data were averaged for voxels within 1-cm gravitational planes, starting from the most gravitationally dependent lung. The slope of the relationship between alveolar ventilation and vertical height was less prone than supine (-0.17 ± 0.10 ml·min(-1)·ml(-1)·cm(-1) supine, -0.040 ± 0.03 prone ml·min(-1)·ml(-1)·cm(-1), P = 0.02) as was the slope of the perfusion-height relationship (-0.14 ± 0.05 ml·min(-1)·ml(-1)·cm(-1) supine, -0.08 ± 0.09 prone ml·min(-1)·ml(-1)·cm(-1), P = 0.02). There was a significant gravitational gradient in Va/Q ratio in both postures (P < 0.05) that was less in prone (0.09 ± 0.08 cm(-1) supine, 0.04 ± 0.03 cm(-1) prone, P = 0.04). The gravitational gradients in ventilation, perfusion, and regional Va/Q ratio were greater supine than prone, suggesting an interplay between thoracic cavity configuration, airway and vascular tree anatomy, and the effects of gravity on Va/Q matching.

  15. The gravitational distribution of ventilation-perfusion ratio is more uniform in prone than supine posture in the normal human lung

    PubMed Central

    Sá, Rui Carlos; Theilmann, Rebecca J.; Buxton, Richard B.; Prisk, G. Kim; Hopkins, Susan R.

    2013-01-01

    The gravitational gradient of intrapleural pressure is suggested to be less in prone posture than supine. Thus the gravitational distribution of ventilation is expected to be more uniform prone, potentially affecting regional ventilation-perfusion (V̇a/Q̇) ratio. Using a novel functional lung magnetic resonance imaging technique to measure regional V̇a/Q̇ ratio, the gravitational gradients in proton density, ventilation, perfusion, and V̇a/Q̇ ratio were measured in prone and supine posture. Data were acquired in seven healthy subjects in a single sagittal slice of the right lung at functional residual capacity. Regional specific ventilation images quantified using specific ventilation imaging and proton density images obtained using a fast gradient-echo sequence were registered and smoothed to calculate regional alveolar ventilation. Perfusion was measured using arterial spin labeling. Ventilation (ml·min−1·ml−1) images were combined on a voxel-by-voxel basis with smoothed perfusion (ml·min−1·ml−1) images to obtain regional V̇a/Q̇ ratio. Data were averaged for voxels within 1-cm gravitational planes, starting from the most gravitationally dependent lung. The slope of the relationship between alveolar ventilation and vertical height was less prone than supine (−0.17 ± 0.10 ml·min−1·ml−1·cm−1 supine, −0.040 ± 0.03 prone ml·min−1·ml−1·cm−1, P = 0.02) as was the slope of the perfusion-height relationship (−0.14 ± 0.05 ml·min−1·ml−1·cm−1 supine, −0.08 ± 0.09 prone ml·min−1·ml−1·cm−1, P = 0.02). There was a significant gravitational gradient in V̇a/Q̇ ratio in both postures (P < 0.05) that was less in prone (0.09 ± 0.08 cm−1 supine, 0.04 ± 0.03 cm−1 prone, P = 0.04). The gravitational gradients in ventilation, perfusion, and regional V̇a/Q̇ ratio were greater supine than prone, suggesting an interplay between thoracic cavity configuration, airway and vascular tree anatomy, and the effects of

  16. 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

    SciTech Connect

    Diot, Q; Kavanagh, B; Miften, M

    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

  17. Motion mitigation for lung cancer patients treated with active scanning proton therapy

    SciTech Connect

    Grassberger, Clemens; Dowdell, Stephen; Sharp, Greg; Paganetti, Harald

    2015-05-15

    Purpose: Motion interplay can affect the tumor dose in scanned proton beam therapy. This study assesses the ability of rescanning and gating to mitigate interplay effects during lung treatments. Methods: The treatments of five lung cancer patients [48 Gy(RBE)/4fx] with varying tumor size (21.1–82.3 cm{sup 3}) and motion amplitude (2.9–30.6 mm) were simulated employing 4D Monte Carlo. The authors investigated two spot sizes (σ ∼ 12 and ∼3 mm), three rescanning techniques (layered, volumetric, breath-sampled volumetric) and respiratory gating with a 30% duty cycle. Results: For 4/5 patients, layered rescanning 6/2 times (for the small/large spot size) maintains equivalent uniform dose within the target >98% for a single fraction. Breath sampling the timing of rescanning is ∼2 times more effective than the same number of continuous rescans. Volumetric rescanning is sensitive to synchronization effects, which was observed in 3/5 patients, though not for layered rescanning. For the large spot size, rescanning compared favorably with gating in terms of time requirements, i.e., 2x-rescanning is on average a factor ∼2.6 faster than gating for this scenario. For the small spot size however, 6x-rescanning takes on average 65% longer compared to gating. Rescanning has no effect on normal lung V{sub 20} and mean lung dose (MLD), though it reduces the maximum lung dose by on average 6.9 ± 2.4/16.7 ± 12.2 Gy(RBE) for the large and small spot sizes, respectively. Gating leads to a similar reduction in maximum dose and additionally reduces V{sub 20} and MLD. Breath-sampled rescanning is most successful in reducing the maximum dose to the normal lung. Conclusions: Both rescanning (2–6 times, depending on the beam size) as well as gating was able to mitigate interplay effects in the target for 4/5 patients studied. Layered rescanning is superior to volumetric rescanning, as the latter suffers from synchronization effects in 3/5 patients studied. Gating minimizes the

  18. Motion mitigation for lung cancer patients treated with active scanning proton therapy

    PubMed Central

    Grassberger, Clemens; Dowdell, Stephen; Sharp, Greg; Paganetti, Harald

    2015-01-01

    Purpose: Motion interplay can affect the tumor dose in scanned proton beam therapy. This study assesses the ability of rescanning and gating to mitigate interplay effects during lung treatments. Methods: The treatments of five lung cancer patients [48 Gy(RBE)/4fx] with varying tumor size (21.1–82.3 cm3) and motion amplitude (2.9–30.6 mm) were simulated employing 4D Monte Carlo. The authors investigated two spot sizes (σ ∼ 12 and ∼3 mm), three rescanning techniques (layered, volumetric, breath-sampled volumetric) and respiratory gating with a 30% duty cycle. Results: For 4/5 patients, layered rescanning 6/2 times (for the small/large spot size) maintains equivalent uniform dose within the target >98% for a single fraction. Breath sampling the timing of rescanning is ∼2 times more effective than the same number of continuous rescans. Volumetric rescanning is sensitive to synchronization effects, which was observed in 3/5 patients, though not for layered rescanning. For the large spot size, rescanning compared favorably with gating in terms of time requirements, i.e., 2x-rescanning is on average a factor ∼2.6 faster than gating for this scenario. For the small spot size however, 6x-rescanning takes on average 65% longer compared to gating. Rescanning has no effect on normal lung V20 and mean lung dose (MLD), though it reduces the maximum lung dose by on average 6.9 ± 2.4/16.7 ± 12.2 Gy(RBE) for the large and small spot sizes, respectively. Gating leads to a similar reduction in maximum dose and additionally reduces V20 and MLD. Breath-sampled rescanning is most successful in reducing the maximum dose to the normal lung. Conclusions: Both rescanning (2–6 times, depending on the beam size) as well as gating was able to mitigate interplay effects in the target for 4/5 patients studied. Layered rescanning is superior to volumetric rescanning, as the latter suffers from synchronization effects in 3/5 patients studied. Gating minimizes the irradiated volume

  19. Thallium myocardial perfusion scans for the assessment of right ventricular hypertrophy in patients with cystic fibrosis. A comparison with other noninvasive techniques

    SciTech Connect

    Newth, C.J.; Corey, M.L.; Fowler, R.S.; Gilday, D.L.; Gross, D.; Mitchell, I.

    1981-01-01

    The incidence of right ventricular hypertrophy in 32 patients with cystic fibrosis was studied using thallium 201 (TI-201) myocardial perfusion scans, and compared with other noninvasive techniques including electrocardiography, vectorcardiography, and M-mode echocardiography. The patients (mean age, 17.3 yr; range, 7 to 33) had a wide range of clinical and pulmonary abnormalities (mean Shwachman-Kulczycki score, 66.6). In the total study group, TI-201 scans, like the vectorcardiograms and the M-mode echocardiograms, gave a surprisingly high proportion of positive predictions for right ventricular hypertrophy (RVH) (44%). The correlations with all other noninvasive methods were uniformly poor, so caution must be exercised in using this technique to predict early RVH in order to follow the natural history of cor pulmonale in cystic fibrosis. At the time of the study, 6 patients had clinical evidence of right ventricular failure, and in this disease setting must have had RVH. In 3 patients, RVH was confirmed at autopsy, and it was successfully predicted by TI-201 scans in 5 of the 6 patients. The false negative scan may have been due to regional myocardial ischemia secondary to severe right ventricular failure. In contrast, the vectorcardiogram, using Fowler's new criteria, made a successful prediction of RVH in all 6 patients, and the electro cardiogram in only 3. Although the M-mode echocardiogram was abnormal in all patients, it would have predicted RVH (with increased right ventricular anterior wall thickness) in only 1 patient. We concluded that TI-201 myocardial perfusion cans are good at confirming RVH in cases with established right ventricular failure, but have no advantage over vectorcardiographic assessments, which are logistically easier to perform and carry no radiation risks.

  20. SCAN+

    SciTech Connect

    Kenneth Krebs, John Svoboda

    2009-11-01

    SCAN+ is a software application specifically designed to control the positioning of a gamma spectrometer by a two dimensional translation system above spent fuel bundles located in a sealed spent fuel cask. The gamma spectrometer collects gamma spectrum information for the purpose of spent fuel cask fuel loading verification. SCAN+ performs manual and automatic gamma spectrometer positioning functions as-well-as exercising control of the gamma spectrometer data acquisitioning functions. Cask configuration files are used to determine the positions of spent fuel bundles. Cask scanning files are used to determine the desired scan paths for scanning a spent fuel cask allowing for automatic unattended cask scanning that may take several hours.

  1. Improvement of the embalming perfusion method: the innovation and the results by light and scanning electron microscopy.

    PubMed

    Goyri-O'Neill, João; Pais, Diogo; Freire de Andrade, Francisco; Ribeiro, Paulo; Belo, Ana; O'Neill, Assunção; Ramos, Samuel; Neves Marques, Cláudia

    2013-01-01

    Embalming is a chemical process that aims the preservation and sanitization of the human body indefinitely. The technique of embalming is an important tool in teaching and research in anatomy enabling the preservation of cadaveric material in good conditions (lessening any significant structural changes and maintaining the natural appearance). This article presents the results of embalmed cadavers in the course of arterial perfusion, through the use of a perfusion machine, particularly designed to this objective, and which allows the control of the embalming fluid injection process. The influence of this technique and the optimization of its parameters on the final quality of embalming were evaluated by sequential histological analysis of the cadaveric tissues using an original method of classification of samples collected from 17 deceased corpses of the Corpses Donation Office of the Department of Anatomy of Faculdade de Ciências Médicas from Universidade Nova de Lisboa, subject to the embalming technique developed in the Department. We concluded that, with this method, there is a decrease of the decomposition process at the time of embalming, which is effective at long term (over a year), requiring merely the maintenance of the body at low temperatures (4° C) and it is possible to observe that the tissue best preserved over time is muscle, showing a conservation considered optimal.

  2. Systematic evaluation of four-dimensional hybrid depth scanning for carbon-ion lung therapy

    SciTech Connect

    Mori, Shinichiro; Furukawa, Takuji; Inaniwa, Taku; Zenklusen, Silvan; Nakao, Minoru; Shirai, Toshiyuki; Noda, Koji

    2013-03-15

    Purpose: Irradiation of a moving target with a scanning beam requires a comprehensive understanding of organ motion as well as a robust dose error mitigation technique. The authors studied the effects of intrafractional respiratory motion for carbon-ion pencil beam scanning with phase-controlled rescanning on dose distributions for lung tumors. To address density variations, they used 4DCT data. Methods: Dose distributions for various rescanning methods, such as simple layer rescanning (LR), volumetric rescanning, and phase-controlled rescanning (PCR), were calculated for a lung phantom and a lung patient studies. To ensure realism, they set the scanning parameters such as scanning velocity and energy variation time to be similar to those used at our institution. Evaluation metrics were determined with regard to clinical relevance, and consisted of (i) phase-controlled rescanning, (ii) sweep direction, (iii) target motion (direction and amplitude), (iv) respiratory cycle, and (v) prescribed dose. Spot weight maps were calculated by using a beam field-specific target volume, which takes account of range variations for respective respiratory phases. To emphasize the impact of intrafractional motion on the dose distribution, respiratory gating was not used. The accumulated dose was calculated by applying a B-spline-based deformable image registration, and the results for phase-controlled layered rescanning (PCR{sub L}) and phase-controlled volumetric rescanning (PCR{sub V}) were compared. Results: For the phantom study, simple LR was unable to improve the dose distributions for an increased number of rescannings. The phase-controlled technique without rescanning (1 Multiplication-Sign PCR{sub L} and 1 Multiplication-Sign PCR{sub V}) degraded dose conformity significantly due to a reduced scan velocity. In contrast, 4 Multiplication-Sign PCR{sub L} or more significantly and consistently improved dose distribution. PCR{sub V} showed interference effects, but in general

  3. [Peripheral lung adenocarcinoma versus squamous cell carcinoma: evaluation with first-pass perfusion imaging using 64-detector row CT].

    PubMed

    Li, Yuan; Yang, Zhigang; Chen, Tianwu; Yu, Jianqun; Deng, Yuping; Li, Zhenlin

    2009-04-01

    The aim of this study was to elucidate the characteristics of time attenuation curve and CT perfusion parameters for pulmonary adenocarcinomas and squamous cell carcinomas. 58 cases of pulmonary adenocarcinomas and 27 cases of squamous cell carcinomas underwent first pass CT perfusion imaging with 64-row MDCT. Data were analyzed using commercial software to generate time attenuation curve (TAC) and CT perfusion parameters, including perfusion, peak enhanced (PE), time to peak (TTP), and blood volume (BV). For TAC, there were 36.2% of type I and 63.8% of type II in adenocarcinomas, while there were 22.2% of type I and 77.8% of type II in squamous cell carcinomas. There was not significant difference (P>0.05). Perfusion, PE, TTP and BV of adenocarcinomas were 63.2 +/- 45.4 ml x min(-1) x ml(-1), 60.2 +/- 46.6 Hu, 34.8 +/- 10.2 s and 34.3 +/- 23.6 ml x 100 g(-1), respectively, while 54.3 +/- 50.2 ml x min(-1) x ml(-1), 48.5 +/- 34.9 Hu, 36.1 +/- 11.2 s and 27.6 +/- 21.7 ml x 100 g(-1), for squamous cell carcinoma, respectively. No significant differences were found between groups (P>0.05). No significant differences in TAC and CT perfusion parameters were found between adenocarcinomas and squamous cell carcinomas.

  4. SCAN+

    2009-11-01

    SCAN+ is a software application specifically designed to control the positioning of a gamma spectrometer by a two dimensional translation system above spent fuel bundles located in a sealed spent fuel cask. The gamma spectrometer collects gamma spectrum information for the purpose of spent fuel cask fuel loading verification. SCAN+ performs manual and automatic gamma spectrometer positioning functions as-well-as exercising control of the gamma spectrometer data acquisitioning functions. Cask configuration files are used to determinemore » the positions of spent fuel bundles. Cask scanning files are used to determine the desired scan paths for scanning a spent fuel cask allowing for automatic unattended cask scanning that may take several hours.« less

  5. TU-F-BRF-03: Effect of Radiation Therapy Planning Scan Registration On the Dose in Lung Cancer Patient CT Scans

    SciTech Connect

    Cunliffe, A; Contee, C; White, B; Justusson, J; Armato, S; Malik, R; Al-Hallaq, H

    2014-06-15

    Purpose: To characterize the effect of deformable registration of serial computed tomography (CT) scans on the radiation dose calculated from a treatment planning scan. Methods: Eighteen patients who received curative doses (≥60Gy, 2Gy/fraction) of photon radiation therapy for lung cancer treatment were retrospectively identified. For each patient, a diagnostic-quality pre-therapy (4–75 days) CT scan and a treatment planning scan with an associated dose map calculated in Pinnacle were collected. To establish baseline correspondence between scan pairs, a researcher manually identified anatomically corresponding landmark point pairs between the two scans. Pre-therapy scans were co-registered with planning scans (and associated dose maps) using the Plastimatch demons and Fraunhofer MEVIS deformable registration algorithms. Landmark points in each pretherapy scan were automatically mapped to the planning scan using the displacement vector field output from both registration algorithms. The absolute difference in planned dose (|ΔD|) between manually and automatically mapped landmark points was calculated. Using regression modeling, |ΔD| was modeled as a function of the distance between manually and automatically matched points (registration error, E), the dose standard deviation (SD-dose) in the eight-pixel neighborhood, and the registration algorithm used. Results: 52–92 landmark point pairs (median: 82) were identified in each patient's scans. Average |ΔD| across patients was 3.66Gy (range: 1.2–7.2Gy). |ΔD| was significantly reduced by 0.53Gy using Plastimatch demons compared with Fraunhofer MEVIS. |ΔD| increased significantly as a function of E (0.39Gy/mm) and SD-dose (2.23Gy/Gy). Conclusion: An average error of <4Gy in radiation dose was introduced when points were mapped between CT scan pairs using deformable registration. Dose differences following registration were significantly increased when the Fraunhofer MEVIS registration algorithm was used

  6. Correlation of spicule sign on computed tomography scans with peripheral lung cancers associated with interstitial lung disease and chronic obstructive pulmonary disease.

    PubMed

    Chen, L; Gao, L; Wu, W L

    2015-03-27

    The objective of this study was to investigate the correlation between spicular signs on computed tomography (CT) scans and peripheral lung cancer (PLC) that is associated with interstitial lung disease (ILD) and chronic obstructive pulmonary disease (COPD). We analyzed clinical data from 96 PLC cases and grouped patients based on whether they had interstitial pneumonia into either ILD/COPD group or non-ILD/COPD group. The occurrence rate of spicule sign was 90.3% in the ILD/COPD group and 61.8% in the non-ILD/COPD group, respectively. There was a significant difference between these groups (P < 0.05). There were no significant differences in the occurrence rate of spicular signs among patients with different pathological types of PLC. The severity of ILD affected the spicular morphology on CT scans directly. There was a significant correlation between the appearance of spicule sign on CT scans and PLC that was associated with ILD/COPD.

  7. Comparison of Two Deformable Registration Algorithms in the Presence of Radiologic Change Between Serial Lung CT Scans.

    PubMed

    Cunliffe, Alexandra R; White, Bradley; Justusson, Julia; Straus, Christopher; Malik, Renuka; Al-Hallaq, Hania A; Armato, Samuel G

    2015-12-01

    We evaluated the image registration accuracy achieved using two deformable registration algorithms when radiation-induced normal tissue changes were present between serial computed tomography (CT) scans. Two thoracic CT scans were collected for each of 24 patients who underwent radiation therapy (RT) treatment for lung cancer, eight of whom experienced radiologically evident normal tissue damage between pre- and post-RT scan acquisition. For each patient, 100 landmark point pairs were manually placed in anatomically corresponding locations between each pre- and post-RT scan. Each post-RT scan was then registered to the pre-RT scan using (1) the Plastimatch demons algorithm and (2) the Fraunhofer MEVIS algorithm. The registration accuracy for each scan pair was evaluated by comparing the distance between landmark points that were manually placed in the post-RT scans and points that were automatically mapped from pre- to post-RT scans using the displacement vector fields output by the two registration algorithms. For both algorithms, the registration accuracy was significantly decreased when normal tissue damage was present in the post-RT scan. Using the Plastimatch algorithm, registration accuracy was 2.4 mm, on average, in the absence of radiation-induced damage and 4.6 mm, on average, in the presence of damage. When the Fraunhofer MEVIS algorithm was instead used, registration errors decreased to 1.3 mm, on average, in the absence of damage and 2.5 mm, on average, when damage was present. This work demonstrated that the presence of lung tissue changes introduced following RT treatment for lung cancer can significantly decrease the registration accuracy achieved using deformable registration.

  8. Comparison of Two Deformable Registration Algorithms in the Presence of Radiologic Change Between Serial Lung CT Scans.

    PubMed

    Cunliffe, Alexandra R; White, Bradley; Justusson, Julia; Straus, Christopher; Malik, Renuka; Al-Hallaq, Hania A; Armato, Samuel G

    2015-12-01

    We evaluated the image registration accuracy achieved using two deformable registration algorithms when radiation-induced normal tissue changes were present between serial computed tomography (CT) scans. Two thoracic CT scans were collected for each of 24 patients who underwent radiation therapy (RT) treatment for lung cancer, eight of whom experienced radiologically evident normal tissue damage between pre- and post-RT scan acquisition. For each patient, 100 landmark point pairs were manually placed in anatomically corresponding locations between each pre- and post-RT scan. Each post-RT scan was then registered to the pre-RT scan using (1) the Plastimatch demons algorithm and (2) the Fraunhofer MEVIS algorithm. The registration accuracy for each scan pair was evaluated by comparing the distance between landmark points that were manually placed in the post-RT scans and points that were automatically mapped from pre- to post-RT scans using the displacement vector fields output by the two registration algorithms. For both algorithms, the registration accuracy was significantly decreased when normal tissue damage was present in the post-RT scan. Using the Plastimatch algorithm, registration accuracy was 2.4 mm, on average, in the absence of radiation-induced damage and 4.6 mm, on average, in the presence of damage. When the Fraunhofer MEVIS algorithm was instead used, registration errors decreased to 1.3 mm, on average, in the absence of damage and 2.5 mm, on average, when damage was present. This work demonstrated that the presence of lung tissue changes introduced following RT treatment for lung cancer can significantly decrease the registration accuracy achieved using deformable registration. PMID:25822396

  9. On the interplay effects with proton scanning beams in stage III lung cancer

    SciTech Connect

    Li, Yupeng; Kardar, Laleh; Liao, Li; Lim, Gino; Li, Xiaoqiang; Li, Heng; Zhu, Ronald X.; Sahoo, Narayan; Gillin, Michael; Zhang, Xiaodong; Cao, Wenhua; Chang, Joe Y.; Liao, Zhongxing; Komaki, Ritsuko; Cox, James D.

    2014-02-15

    Purpose: To assess the dosimetric impact of interplay between spot-scanning proton beam and respiratory motion in intensity-modulated proton therapy (IMPT) for stage III lung cancer. Methods: Eleven patients were sampled from 112 patients with stage III nonsmall cell lung cancer to well represent the distribution of 112 patients in terms of target size and motion. Clinical target volumes (CTVs) and planning target volumes (PTVs) were defined according to the authors' clinical protocol. Uniform and realistic breathing patterns were considered along with regular- and hypofractionation scenarios. The dose contributed by a spot was fully calculated on the computed tomography (CT) images corresponding to the respiratory phase that the spot is delivered, and then accumulated to the reference phase of the 4DCT to generate the dynamic dose that provides an estimation of what might be delivered under the influence of interplay effect. The dynamic dose distributions at different numbers of fractions were compared with the corresponding 4D composite dose which is the equally weighted average of the doses, respectively, computed on respiratory phases of a 4DCT image set. Results: Under regular fractionation, the average and maximum differences in CTV coverage between the 4D composite and dynamic doses after delivery of all 35 fractions were no more than 0.2% and 0.9%, respectively. The maximum differences between the two dose distributions for the maximum dose to the spinal cord, heart V40, esophagus V55, and lung V20 were 1.2 Gy, 0.1%, 0.8%, and 0.4%, respectively. Although relatively large differences in single fraction, correlated with small CTVs relative to motions, were observed, the authors' biological response calculations suggested that this interfractional dose variation may have limited biological impact. Assuming a hypofractionation scenario, the differences between the 4D composite and dynamic doses were well confined even for single fraction. Conclusions: Despite

  10. Comparison of Hemodynamic Effects and Negative Predictive Value of Normal Adenosine Gated Myocardial Perfusion Scan With or Without Caffeine Abstinence

    PubMed Central

    uz Zaman, Maseeh; Fatima, Nosheen; Zaman, Areeba; Zaman, Unaiza; Tahseen, Rabia

    2016-01-01

    For vasodilator stress, myocardial perfusion imaging (MPI) with at least 12-h caffeine abstinence is recommended, as it attenuates cardiovascular hyperemic response of adenosine and dipyridamole. However, many published conflicting results have shown no significant effect upon perfusion abnormalities in MPI performed without caffeine abstinence. The aim of this study was to compare the hemodynamic changes and negative predictive value (NPV) of normal MPIs with adenosine stress performed with or without caffeine abstinence. This was a prospective study that accrued 50 patients from May 2013 till September 2013 and followed till November 2014. These patients had a normal adenosine-gated MPI (GMPI) with technetium-99m methoxy isobutyl isonitrile (99mTc-MIBI) after 12-h caffeine abstinence (no-caffeine). Next day, all patients had a repeat adenosine stress within 60 min after ingestion of a cup of coffee (about 80 mg of caffeine) followed by no MPI in 30 patients due to concern about radiation dose (prior-caffeine adenosine—no MPI; group A). Twenty patients opted for a repeat MPI (prior-caffeine adenosine—MPI; group B). Adenosine-induced hemodynamic response and NPV of the normal MPI with no-caffeine and prior-caffeine protocols were compared. The mean age of the study cohort was 57 ± 9 years with a male-to-female ratio of 76:24% and mean body mass index (BMI) of 26.915 ± 4.121 kg/m2. Prevalence of hypertension, diabetes, dyslipidemia, and positive family history were 76%, 20%, 22%, and 17%, respectively. Comparison of group A with group B revealed no significant difference in demographic parameters, hemodynamic or electrocardiography (ECG) parameters, or left ventricular (LV) function parameters during adenosine intervention with prior-caffeine and no-caffeine protocols. During the follow-up, no fatal myocardial infarction (MI) was reported but 6 nonfatal MIs were reported based upon the history of short hospitalization for chest pain but without biochemical or

  11. Comparison of Hemodynamic Effects and Negative Predictive Value of Normal Adenosine Gated Myocardial Perfusion Scan With or Without Caffeine Abstinence

    PubMed Central

    uz Zaman, Maseeh; Fatima, Nosheen; Zaman, Areeba; Zaman, Unaiza; Tahseen, Rabia

    2016-01-01

    For vasodilator stress, myocardial perfusion imaging (MPI) with at least 12-h caffeine abstinence is recommended, as it attenuates cardiovascular hyperemic response of adenosine and dipyridamole. However, many published conflicting results have shown no significant effect upon perfusion abnormalities in MPI performed without caffeine abstinence. The aim of this study was to compare the hemodynamic changes and negative predictive value (NPV) of normal MPIs with adenosine stress performed with or without caffeine abstinence. This was a prospective study that accrued 50 patients from May 2013 till September 2013 and followed till November 2014. These patients had a normal adenosine-gated MPI (GMPI) with technetium-99m methoxy isobutyl isonitrile (99mTc-MIBI) after 12-h caffeine abstinence (no-caffeine). Next day, all patients had a repeat adenosine stress within 60 min after ingestion of a cup of coffee (about 80 mg of caffeine) followed by no MPI in 30 patients due to concern about radiation dose (prior-caffeine adenosine—no MPI; group A). Twenty patients opted for a repeat MPI (prior-caffeine adenosine—MPI; group B). Adenosine-induced hemodynamic response and NPV of the normal MPI with no-caffeine and prior-caffeine protocols were compared. The mean age of the study cohort was 57 ± 9 years with a male-to-female ratio of 76:24% and mean body mass index (BMI) of 26.915 ± 4.121 kg/m2. Prevalence of hypertension, diabetes, dyslipidemia, and positive family history were 76%, 20%, 22%, and 17%, respectively. Comparison of group A with group B revealed no significant difference in demographic parameters, hemodynamic or electrocardiography (ECG) parameters, or left ventricular (LV) function parameters during adenosine intervention with prior-caffeine and no-caffeine protocols. During the follow-up, no fatal myocardial infarction (MI) was reported but 6 nonfatal MIs were reported based upon the history of short hospitalization for chest pain but without biochemical or

  12. Comparison of Hemodynamic Effects and Negative Predictive Value of Normal Adenosine Gated Myocardial Perfusion Scan With or Without Caffeine Abstinence.

    PubMed

    Uz Zaman, Maseeh; Fatima, Nosheen; Zaman, Areeba; Zaman, Unaiza; Tahseen, Rabia

    2016-09-01

    For vasodilator stress, myocardial perfusion imaging (MPI) with at least 12-h caffeine abstinence is recommended, as it attenuates cardiovascular hyperemic response of adenosine and dipyridamole. However, many published conflicting results have shown no significant effect upon perfusion abnormalities in MPI performed without caffeine abstinence. The aim of this study was to compare the hemodynamic changes and negative predictive value (NPV) of normal MPIs with adenosine stress performed with or without caffeine abstinence. This was a prospective study that accrued 50 patients from May 2013 till September 2013 and followed till November 2014. These patients had a normal adenosine-gated MPI (GMPI) with technetium-99m methoxy isobutyl isonitrile ((99m)Tc-MIBI) after 12-h caffeine abstinence (no-caffeine). Next day, all patients had a repeat adenosine stress within 60 min after ingestion of a cup of coffee (about 80 mg of caffeine) followed by no MPI in 30 patients due to concern about radiation dose (prior-caffeine adenosine-no MPI; group A). Twenty patients opted for a repeat MPI (prior-caffeine adenosine-MPI; group B). Adenosine-induced hemodynamic response and NPV of the normal MPI with no-caffeine and prior-caffeine protocols were compared. The mean age of the study cohort was 57 ± 9 years with a male-to-female ratio of 76:24% and mean body mass index (BMI) of 26.915 ± 4.121 kg/m(2). Prevalence of hypertension, diabetes, dyslipidemia, and positive family history were 76%, 20%, 22%, and 17%, respectively. Comparison of group A with group B revealed no significant difference in demographic parameters, hemodynamic or electrocardiography (ECG) parameters, or left ventricular (LV) function parameters during adenosine intervention with prior-caffeine and no-caffeine protocols. During the follow-up, no fatal myocardial infarction (MI) was reported but 6 nonfatal MIs were reported based upon the history of short hospitalization for chest pain but without biochemical or

  13. [Unilateral hyperlucent lung induced by a carcinoid tumor: comments on the differential diagnosis and mechanisms of hypoperfusion].

    PubMed

    Schmitz, N; Bugnet, A-S; Demian, M; Massard, G; De Blay, F; Pauli, G

    2005-04-01

    We report the case of a 35-year-old woman in whom a systematic thoracic x-ray led to the diagnosis of unilateral hyperlucent lung due to a carcinoid tumor obstructing the main left bronchus almost completely. Injected computed tomography permitted diagnosis of left lung hypoperfusion and visualization of the tumor. After enlarged inferior left lobar resection, normal perfusion was observed six months later on the isotopic lung perfusion scan. Other reported causes of unilateral hyperlucent lung are discussed as well as pathophysiological mechanisms of lung hypoperfusion and hypoxic vasoconstriction.

  14. [Unilateral hyperlucent lung induced by a carcinoid tumor: comments on the differential diagnosis and mechanisms of hypoperfusion].

    PubMed

    Schmitz, N; Bugnet, A-S; Demian, M; Massard, G; De Blay, F; Pauli, G

    2005-04-01

    We report the case of a 35-year-old woman in whom a systematic thoracic x-ray led to the diagnosis of unilateral hyperlucent lung due to a carcinoid tumor obstructing the main left bronchus almost completely. Injected computed tomography permitted diagnosis of left lung hypoperfusion and visualization of the tumor. After enlarged inferior left lobar resection, normal perfusion was observed six months later on the isotopic lung perfusion scan. Other reported causes of unilateral hyperlucent lung are discussed as well as pathophysiological mechanisms of lung hypoperfusion and hypoxic vasoconstriction. PMID:16012363

  15. Update on donor assessment, resuscitation, and acceptance criteria, including novel techniques--non-heart-beating donor lung retrieval and ex vivo donor lung perfusion.

    PubMed

    Yeung, Jonathan C; Cypel, Marcelo; Waddell, Thomas K; van Raemdonck, Dirk; Keshavjee, Shaf

    2009-05-01

    The shortage of adequate organ donors remains a great challenge in clinical lung transplantation. With increasing experience in the medical management and surgical technique of lung transplantation, gradual expansion of the criteria for lung donor selection has occurred with beneficial effects on the donor pool. Interest in donation after cardiac death also is increasing as the gap increases between donors and the needs of listed patients. Successful use of these new sources of lungs depends on the accurate assessment and prediction of transplanted lung function. Promising techniques for lung assessment and diagnostics include investigating key genes associated with graft failure or good graft performance using molecular approaches, and ex vivo evaluation. Further studies are needed to answer remaining questions about the best technique and solution to reperfuse human lungs for several hours without edema formation. As the predictive ability to discern good from injured donor lungs improves, strategies to repair donor lungs become increasingly important. Prolonged normothermic EVLP seems to be a platform on which many reparative strategies can be realized. With these new methods for assessing and resuscitating lungs accurately, it is hoped that inroads will be made toward providing every listed patient a chance for successful lung transplantation. PMID:19662970

  16. Patient dose simulations for scanning-beam digital x-ray tomosynthesis of the lungs

    SciTech Connect

    Nelson, Geoff; Fahrig, Rebecca; Yoon, Sungwon; Krishna, Ganesh; Wilfley, Brian

    2013-11-15

    Purpose: An improved method of image guidance for lung tumor biopsies could help reduce the high rate of false negatives. The aim of this work is to optimize the geometry of the scanning-beam digital tomography system (SBDX) for providing real-time 3D tomographic reconstructions for target verification. The unique geometry of the system requires trade-offs between patient dose, imaging field of view (FOV), and tomographic angle.Methods: Tomosynthetic angle as a function of tumor-to-detector distance was calculated. Monte Carlo Software (PCXMC) was used to calculate organ doses and effective dose for source-to-detector distances (SDDs) from 90 to 150 cm, patient locations with the tumor at 20 cm from the source to 20 cm from the detector, and FOVs centered on left lung and right lung as well as medial and distal peripheries of the lungs. These calculations were done for two systems, a SBDX system and a GE OEC-9800 C-arm fluoroscopic unit. To evaluate the dose effect of the system geometry, results from PCXMC were calculated using a scan of 300 mAs for both SBDX and fluoroscopy. The Rose Criterion was used to find the fluence required for a tumor SNR of 5, factoring in scatter, air-gap, system geometry, and patient position for all models generated with PCXMC. Using the calculated fluence for constant tumor SNR, the results from PCXMC were used to compare the patient dose for a given SNR between SBDX and fluoroscopy.Results: Tomographic angle changes with SDD only in the region near the detector. Due to their geometry, the source array and detector have a peak tomographic angle for any given SDD at a source to tumor distance that is 69.7% of the SDD assuming constant source and detector size. Changing the patient location in order to increase tomographic angle has a significant effect on organ dose distribution due to geometrical considerations. With SBDX and fluoroscopy geometries, the dose to organs typically changes in an opposing manner with changing patient

  17. Patient dose simulations for scanning-beam digital x-ray tomosynthesis of the lungs

    PubMed Central

    Nelson, Geoff; Yoon, Sungwon; Krishna, Ganesh; Wilfley, Brian; Fahrig, Rebecca

    2013-01-01

    Purpose: An improved method of image guidance for lung tumor biopsies could help reduce the high rate of false negatives. The aim of this work is to optimize the geometry of the scanning-beam digital tomography system (SBDX) for providing real-time 3D tomographic reconstructions for target verification. The unique geometry of the system requires trade-offs between patient dose, imaging field of view (FOV), and tomographic angle. Methods: Tomosynthetic angle as a function of tumor-to-detector distance was calculated. Monte Carlo Software (PCXMC) was used to calculate organ doses and effective dose for source-to-detector distances (SDDs) from 90 to 150 cm, patient locations with the tumor at 20 cm from the source to 20 cm from the detector, and FOVs centered on left lung and right lung as well as medial and distal peripheries of the lungs. These calculations were done for two systems, a SBDX system and a GE OEC-9800 C-arm fluoroscopic unit. To evaluate the dose effect of the system geometry, results from PCXMC were calculated using a scan of 300 mAs for both SBDX and fluoroscopy. The Rose Criterion was used to find the fluence required for a tumor SNR of 5, factoring in scatter, air-gap, system geometry, and patient position for all models generated with PCXMC. Using the calculated fluence for constant tumor SNR, the results from PCXMC were used to compare the patient dose for a given SNR between SBDX and fluoroscopy. Results: Tomographic angle changes with SDD only in the region near the detector. Due to their geometry, the source array and detector have a peak tomographic angle for any given SDD at a source to tumor distance that is 69.7% of the SDD assuming constant source and detector size. Changing the patient location in order to increase tomographic angle has a significant effect on organ dose distribution due to geometrical considerations. With SBDX and fluoroscopy geometries, the dose to organs typically changes in an opposing manner with changing patient

  18. Endobronchial mucosal blanching due to a post-lung transplantation pulmonary artery stenosis.

    PubMed

    Slebos, Dirk-Jan; Wolff, Rienhart F E; van der Bij, Wim

    2011-03-01

    A 45-year-old woman underwent a bronchoscopy shortly after lung transplantation. The airway mucosal appearance significantly differed between both lungs, with a pale aspect of the left bronchial tree. Computed tomography (CT) and perfusion scan confirmed a left pulmonary artery stenosis, improving with conservative treatment.

  19. Mid-ventilation CT scan construction from four-dimensional respiration-correlated CT scans for radiotherapy planning of lung cancer patients

    SciTech Connect

    Wolthaus, Jochem; Schneider, Christoph; Sonke, Jan-Jakob; Herk, Marcel van; Belderbos, Jose; Rossi, Maddalena; Lebesque, Joos V.; Damen, Eugene M.F. . E-mail: e.damen@nki.nl

    2006-08-01

    Purpose: Four-dimensional (4D) respiration-correlated imaging techniques can be used to obtain (respiration) artifact-free computed tomography (CT) images of the thorax. Current radiotherapy planning systems, however, do not accommodate 4D-CT data. The purpose of this study was to develop a simple, new concept to incorporate patient-specific motion information, using 4D-CT scans, in the radiotherapy planning process of lung cancer patients to enable smaller error margins. Methods and Materials: A single CT scan was selected from the 4D-CT data set. This scan represented the tumor in its time-averaged position over the respiratory cycle (the mid-ventilation CT scan). To select the appropriate CT scan, two methods were used. First, the three-dimensional tumor motion was analyzed semiautomatically to calculate the mean tumor position and the corresponding respiration phase. An alternative automated method was developed to select the correct CT scan using the diaphragm motion. Results: Owing to hysteresis, mid-ventilation selection using the three-dimensional tumor motion had a tumor position accuracy (with respect to the mean tumor position) better than 1.1 {+-} 1.1 mm for all three directions (inhalation and exhalation). The accuracy in the diaphragm motion method was better than 1.1 {+-} 1.1 mm. Conventional free-breathing CT scanning had an accuracy better than 0 {+-} 3.9 mm. The mid-ventilation concept can result in an average irradiated volume reduction of 20% for tumors with a diameter of 40 mm. Conclusion: Tumor motion and the diaphragm motion method can be used to select the (artifact-free) mid-ventilation CT scan, enabling a significant reduction of the irradiated volume.

  20. Lung texture in serial thoracic CT scans: correlation with radiologist-defined severity of acute changes following radiation therapy

    NASA Astrophysics Data System (ADS)

    Cunliffe, Alexandra R.; Armato, Samuel G., III; Straus, Christopher; Malik, Renuka; Al-Hallaq, Hania A.

    2014-09-01

    This study examines the correlation between the radiologist-defined severity of normal tissue damage following radiation therapy (RT) for lung cancer treatment and a set of mathematical descriptors of computed tomography (CT) scan texture (‘texture features’). A pre-therapy CT scan and a post-therapy CT scan were retrospectively collected under IRB approval for each of the 25 patients who underwent definitive RT (median dose: 66 Gy). Sixty regions of interest (ROIs) were automatically identified in the non-cancerous lung tissue of each post-therapy scan. A radiologist compared post-therapy scan ROIs with pre-therapy scans and categorized each as containing no abnormality, mild abnormality, moderate abnormality, or severe abnormality. Twenty texture features that characterize gray-level intensity, region morphology, and gray-level distribution were calculated in post-therapy scan ROIs and compared with anatomically matched ROIs in the pre-therapy scan. Linear regression and receiver operating characteristic (ROC) analysis were used to compare the percent feature value change (ΔFV) between ROIs at each category of visible radiation damage. Most ROIs contained no (65%) or mild abnormality (30%). ROIs with moderate (3%) or severe (2%) abnormalities were observed in 9 patients. For 19 of 20 features, ΔFV was significantly different among severity levels. For 12 features, significant differences were observed at every level. Compared with regions with no abnormalities, ΔFV for these 12 features increased, on average, by 1.5%, 12%, and 30%, respectively, for mild, moderate, and severe abnormalitites. Area under the ROC curve was largest when comparing ΔFV in the highest severity level with the remaining three categories (mean AUC across features: 0.84). In conclusion, 19 features that characterized the severity of radiologic changes from pre-therapy scans were identified. These features may be used in future studies to quantify acute normal lung tissue damage

  1. Comparison of computed tomography and radionuclide scanning for detection of brain metastases in small cell lung cancer

    SciTech Connect

    Crane, J.M.; Nelson, M.J.; Ihde, D.C.; Makuch, R.W.; Glatstein, E.; Zabell, A.; Johnston-Early, A.; Bates, H.R.; Saini, N.; Cohen, M.H.

    1984-09-01

    Neurologic history and examination, radionuclide brain scans (RN), and computed tomographic brain scans (CT) were performed at diagnosis and sequentially in 153 consecutive patients with small cell lung cancer (SCLC) to assess the sensitivity and accuracy of these screening methods and to determine whether the early detection of brain metastases influences survival. CT scans (sensitivity, 98%; positive predictive accuracy, 98%) were superior to RN scans (sensitivity, 71%; positive predictive accuracy, 86%) in patients with or without neurologic signs or symptoms. However, CT scans were positive in only 6% of asymptomatic patients at diagnosis and 13% of asymptomatic patients after systemic therapy. Brain metastases detected by CT scan were the sole site of extensive-stage disease in 6% of patients at diagnosis. Despite the enhanced ability of CT scans to detect asymptomatic lesions, survival after therapeutic cranial irradiation was similar for asymptomatic and symptomatic patients. The results suggest that CT brain scans should be used routinely in SCLC patients with neurologic signs or symptoms, at diagnosis (when treatment decisions are based on stage), and at six-month intervals in patients with prior brain metastases and in whom erratic follow-up is likely.

  2. CT Perfusion Characteristics Identify Metastatic Sites in Liver.

    PubMed

    Wang, Yuan; Hobbs, Brian P; Ng, Chaan S

    2015-01-01

    Tissue perfusion plays a critical role in oncology because growth and migration of cancerous cells require proliferation of new blood vessels through the process of tumor angiogenesis. Computed tomography (CT) perfusion is an emerging functional imaging modality that measures tissue perfusion through dynamic CT scanning following intravenous administration of contrast medium. This noninvasive technique provides a quantitative basis for assessing tumor angiogenesis. CT perfusion has been utilized on a variety of organs including lung, prostate, liver, and brain, with promising results in cancer diagnosis, disease prognostication, prediction, and treatment monitoring. In this paper, we focus on assessing the extent to which CT perfusion characteristics can be used to discriminate liver metastases from neuroendocrine tumors from normal liver tissues. The neuroendocrine liver metastases were analyzed by distributed parameter modeling to yield tissue blood flow (BF), blood volume (BV), mean transit time (MTT), permeability (PS), and hepatic arterial fraction (HAF), for tumor and normal liver. The result reveals the potential of CT perfusion as a tool for constructing biomarkers from features of the hepatic vasculature for guiding cancer detection, prognostication, and treatment selection.

  3. A solitary large radioiodine accumulative lung lesion in high-dose 131i therapeutic scan: bronchial atresia with mucocele.

    PubMed

    Lee, Won Hyoung; Park, Jung Mi; Kwak, Jeong Ja

    2015-02-01

    We reported a large radioiodine accumulative lung lesion on I therapeutic whole-body scan performed in a 50-year-old woman for thyroid cancer ablation therapy. Previously, her chest radiography and contrast-enhanced chest CT images showed bronchial atresia in the left upper lobar bronchus and mucus-filled dilated distal bronchus. Bronchial mucocele was confirmed by CT-guided percutaneous transthoracic needle aspiration. Bronchial atresia is a rare congenital abnormality associated with the mucocele.

  4. Association of non-traumatic complex regional pain syndrome with adenocarcinoma lung on 99mTc-MDP bone scan

    PubMed Central

    Damle, Nishikant A; Tripathi, Madhavi; Singhal, Abhinav; Bal, Chandrasekhar; Kumar, Praveen; Kandasamy, Devasenathipathi; Jana, Manisha

    2012-01-01

    Complex regional pain syndrome (CRPS) is usually associated with trauma. Rarely, it may be seen in association with malignancies. We present here the bone scan and X-ray findings in the case of a 56-year-male-patient with adenocarcinoma lung who also had non-traumatic CRPS without involvement of the stellate ganglion. The case highlights the fact that spontaneous development of reflex sympathetic dystrophy may be associated with a neoplastic etiology. PMID:24019656

  5. Reconstruction of a time-averaged midposition CT scan for radiotherapy planning of lung cancer patients using deformable registration

    SciTech Connect

    Wolthaus, J. W. H.; Sonke, J.-J.; Herk, M. van; Damen, E. M. F.

    2008-09-15

    Purpose: lower lobe lung tumors move with amplitudes of up to 2 cm due to respiration. To reduce respiration imaging artifacts in planning CT scans, 4D imaging techniques are used. Currently, we use a single (midventilation) frame of the 4D data set for clinical delineation of structures and radiotherapy planning. A single frame, however, often contains artifacts due to breathing irregularities, and is noisier than a conventional CT scan since the exposure per frame is lower. Moreover, the tumor may be displaced from the mean tumor position due to hysteresis. The aim of this work is to develop a framework for the acquisition of a good quality scan representing all scanned anatomy in the mean position by averaging transformed (deformed) CT frames, i.e., canceling out motion. A nonrigid registration method is necessary since motion varies over the lung. Methods and Materials: 4D and inspiration breath-hold (BH) CT scans were acquired for 13 patients. An iterative multiscale motion estimation technique was applied to the 4D CT scan, similar to optical flow but using image phase (gray-value transitions from bright to dark and vice versa) instead. From the (4D) deformation vector field (DVF) derived, the local mean position in the respiratory cycle was computed and the 4D DVF was modified to deform all structures of the original 4D CT scan to this mean position. A 3D midposition (MidP) CT scan was then obtained by (arithmetic or median) averaging of the deformed 4D CT scan. Image registration accuracy, tumor shape deviation with respect to the BH CT scan, and noise were determined to evaluate the image fidelity of the MidP CT scan and the performance of the technique. Results: Accuracy of the used deformable image registration method was comparable to established automated locally rigid registration and to manual landmark registration (average difference to both methods <0.5 mm for all directions) for the tumor region. From visual assessment, the registration was good

  6. Use of maximum intensity projections (MIP) for target volume generation in 4DCT scans for lung cancer

    SciTech Connect

    Underberg, Rene W.M.; Lagerwaard, Frank J. . E-mail: fj.lagerwaard@vumc.nl; Slotman, Ben J.; Cuijpers, Johan P.; Senan, Suresh

    2005-09-01

    Purpose: Single four-dimensional CT (4DCT) scans reliably capture intrafractional tumor mobility for radiotherapy planning, but generating internal target volumes (ITVs) requires the contouring of gross tumor volumes (GTVs) in up to 10 phases of a 4DCT scan, as is routinely performed in our department. We investigated the use of maximum intensity projection (MIP) protocols for rapid generation of ITVs. Methods and Materials: 4DCT data from a mobile phantom and from 12 patients with Stage I lung cancer were analyzed. A single clinician contoured GTVs in all respiratory phases of a 4DCT, as well as in three consecutive phases selected for respiratory gating. MIP images were generated from both phantom and patient data, and ITVs were derived from encompassing volumes of the respective GTVs. Results: In the phantom study, the ratio between ITVs generated from all 10 phases and those from MIP scans was 1.04. The corresponding center of mass of both ITVs differed by less than 1 mm. In scans from patients, good agreement was observed between ITVs derived from 10 and 3 (gating) phases and corresponding MIPs, with ratios of 1.07 {+-} 0.05 and 0.98 {+-} 0.05, respectively. In addition, the center of mass of the respective ITVs differed by only 0.4 and 0.5 mm. Conclusion: MIPs are a reliable clinical tool for generating ITVs from 4DCT data sets, thereby permitting rapid assessment of mobility for both gated and nongated 4D radiotherapy in lung cancer.

  7. Infusion of freshly isolated autologous bone marrow derived mononuclear cells prevents endotoxin-induced lung injury in an ex-vivo perfused swine model

    PubMed Central

    2013-01-01

    Introduction The acute respiratory distress syndrome (ARDS), affects up to 150,000 patients per year in the United States. We and other groups have demonstrated that bone marrow derived mesenchymal stromal stem cells prevent ARDS induced by systemic and local administration of endotoxin (lipopolysaccharide (LPS)) in mice. Methods A study was undertaken to determine the effects of the diverse populations of bone marrow derived cells on the pathophysiology of ARDS, using a unique ex-vivo swine preparation, in which only the ventilated lung and the liver are perfused with autologous blood. Six experimental groups were designated as: 1) endotoxin alone, 2) endotoxin + total fresh whole bone marrow nuclear cells (BMC), 3) endotoxin + non-hematopoietic bone marrow cells (CD45 neg), 4) endotoxin + hematopoietic bone marrow cells (CD45 positive), 5) endotoxin + buffy coat and 6) endotoxin + in vitro expanded swine CD45 negative adherent allogeneic bone marrow cells (cultured CD45neg). We measured at different levels the biological consequences of the infusion of the different subsets of cells. The measured parameters were: pulmonary vascular resistance (PVR), gas exchange (PO2), lung edema (lung wet/dry weight), gene expression and serum concentrations of the pro-inflammatory cytokines IL-1β, TNF-α and IL-6. Results Infusion of freshly purified autologous total BMCs, as well as non-hematopoietic CD45(-) bone marrow cells significantly reduced endotoxin-induced pulmonary hypertension and hypoxemia and reduced the lung edema. Also, in the groups that received BMCs and cultured CD45neg we observed a decrease in the levels of IL-1β and TNF-α in plasma. Infusion of hematopoietic CD45(+) bone marrow cells or peripheral blood buffy coat cells did not protect against LPS-induced lung injury. Conclusions We conclude that infusion of freshly isolated autologous whole bone marrow cells and the subset of non-hematopoietic cells can suppress the acute humoral and physiologic

  8. 99mTc-DTPA aerosol for same-day post-perfusion ventilation imaging: results of a multicentre study.

    PubMed

    Köhn, H; Mostbeck, A; Bachmayr, S; Eber, O; Galvan, G; Holm, C; König, B; Lind, P; Markt, B; Ogris, E

    1993-01-01

    A multicentre study was performed in an attempt to evaluate a submicronic technetium-99m diethylene triamine penta-acetic acid aerosol generated by a newly developed delivery system, the aerosol production equipment (APE nebulizer), for same-day post-perfusion ventilation imaging in patients with clinically suspected pulmonary embolism. Quantitative comparison between the DTPA aerosol and krypton gas demonstrated a close correlation with respect to regional pulmonary distribution of activity and peripheral lung penetration (n = 14, r = 0.94, P < 0.001 and r = 0.75, P < 0.0025, respectively). In 169 consecutive patients, DTPA aerosol images performed immediately following perfusion (inhalation scan I) were compared to those carried out on the next day (inhalation scan II) with respect to image quality and assessment of perfusion-ventilation matches or mismatches. Agreement between inhalation scans I and II with respect to perfusion defects matched or mismatched to ventilation was found in 166/169 (98%) studies. The image quality of inhalation scan I was equal to that of scan II in 72%; inhalation scan I was superior in 11% of cases, while scan II was superior in 17%. This submicronic 99mTc-labelled DTPA aerosol is well suited for fast same-day post-perfusion ventilation imaging in patients with clinical suspicion of pulmonary embolism.

  9. Biological effects of passive versus active scanning proton beams on human lung epithelial cells.

    PubMed

    Gridley, Daila S; Pecaut, Michael J; Mao, Xiao W; Wroe, Andrew J; Luo-Owen, Xian

    2015-02-01

    The goal was to characterize differences in cell response after exposure to active beam scanning (ABS) protons compared to a passive delivery system. Human lung epithelial (HLE) cells were evaluated at various locations along the proton depth dose profile. The dose delivered at the Bragg peak position was essentially identical (∼4 Gy) with the two techniques, but depth dose data showed that ABS resulted in lower doses at entry and more rapid drop-off after the peak. Average dose rates for the passive and ABS beams were 1.1 Gy/min and 5.1 Gy/min, respectively; instantaneous dose rates were 19.2 Gy/min and 2,300 Gy/min (to a 0.5 × 0.5 mm(2) voxel). Analysis of DNA synthesis was based on (3)H-TdR incorporation. Quantitative real-time polymerase chain reaction (RT-PCR) was done to determine expression of genes related to p53 signaling and DNA damage; a total of 152 genes were assessed. Spectral karyotyping and analyses of the Golgi apparatus and cytokines produced by the HLE cells were also performed. At or near the Bragg peak position, ABS protons resulted in a greater decrease in DNA synthesis compared to passively delivered protons. Genes with >2-fold change (P < 0.05 vs. 0 Gy) after passive proton irradiation at one or more locations within the Bragg curve were BTG2, CDKN1A, IFNB1 and SIAH1. In contrast, many more genes had >2-fold difference with ABS protons: BRCA1, BRCA2, CDC25A, CDC25C, CCNB2, CDK1, DMC1, DNMT1, E2F1, EXO1, FEN1, GADD45A, GTSE1, IL-6, JUN, KRAS, MDM4, PRC1, PTTG1, RAD51, RPA1, TNF, WT1, XRCC2, XRCC3 and XRCC6BP1. Spectral karyotyping revealed numerous differences in chromosomal abnormalities between the two delivery systems, especially at or near the Bragg peak. Percentage of cells staining for the Golgi apparatus was low after exposure to passive and active proton beams. Studies such as this are needed to ensure patient safety and make modifications in ABS delivery, if necessary.

  10. Panel Reviews Benefits and Harms of CT Scans for Lung Cancer Screening | Division of Cancer Prevention

    Cancer.gov

    A panel of experts has reviewed the evidence regarding the benefits and harms of screening for lung cancer with low-dose computed tomography (CT) and concluded that the technology may benefit some individuals at high risk for lung cancer. But the panel cautioned that many questions remain about the potential harms of screening and how to translate screening into clinical practice. |

  11. Facility-Level Analysis of PET Scanning for Staging Among US Veterans With Non-small Cell Lung Cancer

    PubMed Central

    Wagner, Todd H.; Schultz, Ellen M.; Xu, Xiangyan; Ghaus, Sharfun J.; Provenzale, Dawn; Au, David H.

    2014-01-01

    Background: PET scanning has been shown in randomized trials to reduce the frequency of surgery without cure among patients with potentially resectable non-small cell lung cancer (NSCLC). We examined whether more frequent use of PET scanning at the facility level improves survival among patients with NSCLC in real-world practice. Methods: In this prospective cohort study of 622 US veterans with newly diagnosed NSCLC, we compared groups defined by the frequency of PET scan use measured at the facility level and categorized as low (< 25%), medium (25%-60%), or high (> 60%). Results: The median age of the sample was 69 years. Ninety-eight percent were men, 36% were Hispanic or nonwhite, and 54% had moderate or severe comorbidities. At low-, medium-, and high-use facilities, PET scan was performed in 13%, 40%, and 72% of patients, respectively (P < .0001). Baseline characteristics were similar across groups, including clinical stage based on CT scanning. More frequent use of PET scanning was associated with more frequent invasive staging (P < .001) and nonsignificant improvements in downstaging (P = .13) and surgery without cure (P = .12). After a median of 352 days of follow-up, 22% of the sample was still alive, including 22% at low- and medium-use facilities and 20% at high-use facilities. After adjustment and compared with patients at low-use facilities, the hazard of death was greater for patients at high-use facilities (adjusted hazard ratio [HR], 1.35; 95% CI, 1.05-1.74) but not different for patients at medium-use facilities (adjusted HR, 1.14; 95% CI, 0.88-1.46). Conclusions: In this study of veterans with NSCLC, markedly greater use of PET scanning at the facility level was associated with more frequent use of invasive staging and possible improvements in downstaging and surgery without cure, but greater use of PET scanning was not associated with better survival. PMID:24306819

  12. Novel automatic detection of pleura and B-lines (comet-tail artifacts) on in vivo lung ultrasound scans

    NASA Astrophysics Data System (ADS)

    Moshavegh, Ramin; Hansen, Kristoffer Lindskov; Møller Sørensen, Hasse; Hemmsen, Martin Christian; Ewertsen, Caroline; Nielsen, Michael Bachmann; Jensen, Jørgen Arendt

    2016-04-01

    This paper presents a novel automatic method for detection of B-lines (comet-tail artifacts) in lung ultrasound scans. B-lines are the most commonly used artifacts for analyzing the pulmonary edema. They appear as laser-like vertical beams, which arise from the pleural line and spread down without fading to the edge of the screen. An increase in their number is associated with presence of edema. All the scans used in this study were acquired using a BK3000 ultrasound scanner (BK Ultrasound, Denmark) driving a 192-element 5:5 MHz wide linear transducer (10L2W, BK Ultrasound). The dynamic received focus technique was employed to generate the sequences. Six subjects, among those three patients after major surgery and three normal subjects, were scanned once and Six ultrasound sequences each containing 50 frames were acquired. The proposed algorithm was applied to all 300 in-vivo lung ultrasound images. The pleural line is first segmented on each image and then the B-line artifacts spreading down from the pleural line are detected and overlayed on the image. The resulting 300 images showed that the mean lateral distance between B-lines detected on images acquired from patients decreased by 20% in compare with that of normal subjects. Therefore, the method can be used as the basis of a method of automatically and qualitatively characterizing the distribution of B-lines.

  13. Effect of deformable registration on the dose calculated in radiation therapy planning CT scans of lung cancer patients

    SciTech Connect

    Cunliffe, Alexandra R.; Armato, Samuel G.; White, Bradley; Justusson, Julia; Contee, Clay; Malik, Renuka; Al-Hallaq, Hania A.

    2015-01-15

    Purpose: To characterize the effects of deformable image registration of serial computed tomography (CT) scans on the radiation dose calculated from a treatment planning scan. Methods: Eighteen patients who received curative doses (≥60 Gy, 2 Gy/fraction) of photon radiation therapy for lung cancer treatment were retrospectively identified. For each patient, a diagnostic-quality pretherapy (4–75 days) CT scan and a treatment planning scan with an associated dose map were collected. To establish correspondence between scan pairs, a researcher manually identified anatomically corresponding landmark point pairs between the two scans. Pretherapy scans then were coregistered with planning scans (and associated dose maps) using the demons deformable registration algorithm and two variants of the Fraunhofer MEVIS algorithm (“Fast” and “EMPIRE10”). Landmark points in each pretherapy scan were automatically mapped to the planning scan using the displacement vector field output from each of the three algorithms. The Euclidean distance between manually and automatically mapped landmark points (d{sub E}) and the absolute difference in planned dose (|ΔD|) were calculated. Using regression modeling, |ΔD| was modeled as a function of d{sub E}, dose (D), dose standard deviation (SD{sub dose}) in an eight-pixel neighborhood, and the registration algorithm used. Results: Over 1400 landmark point pairs were identified, with 58–93 (median: 84) points identified per patient. Average |ΔD| across patients was 3.5 Gy (range: 0.9–10.6 Gy). Registration accuracy was highest using the Fraunhofer MEVIS EMPIRE10 algorithm, with an average d{sub E} across patients of 5.2 mm (compared with >7 mm for the other two algorithms). Consequently, average |ΔD| was also lowest using the Fraunhofer MEVIS EMPIRE10 algorithm. |ΔD| increased significantly as a function of d{sub E} (0.42 Gy/mm), D (0.05 Gy/Gy), SD{sub dose} (1.4 Gy/Gy), and the algorithm used (≤1 Gy). Conclusions: An

  14. Diagnostic Performances of 99mTc-Methoxy Isobutyl Isonitrile Scan in Predicting the Malignancy of Lung Lesions

    PubMed Central

    Zhang, Shuxin; Liu, Yang

    2016-01-01

    Abstract We performed a meta-analysis to evaluate the value of technetium-99m methoxy isobutyl isonitrile (99mTc-MIBI) single photon emission computed tomography (SPECT) in differentiating malignant from benign lung lesions. The PubMed and Embase databases were comprehensively searched for relevant articles that evaluated lung lesions suspicious for malignancy. Two reviewers independently extracted the data on study characteristics and examination results, and assessed the quality of each selected study. The data extracted from the eligible studies were assessed by heterogeneity and threshold effect tests. Pooled sensitivity, specificity, diagnostic odds ratio (DOR), and areas under the summary receiver-operating characteristic curves (SROC) were also calculated. Fourteen studies were included in this meta-analysis. The pooled sensitivity, specificity, positive and negative likelihood ratio, and DOR of 99mTc-MIBI scan in detecting malignant lung lesions were 0.84 (95% confidence interval [CI]: 0.81, 0.87), 0.83 (95% CI: 0.77, 0.88), 4.22 (95% CI: 2.53, 7.04), 0.20 (95% CI: 0.12, 0.31), and 25.71 (95% CI: 10.67, 61.96), respectively. The area under the SROC was 0.9062. Meta-regression analysis showed that the accuracy estimates were significantly influenced by ethnic groups (P < 0.01), but not by image analysis methods, mean lesion size, or year of publication. Deek funnel plot asymmetry test for the overall analysis did not raise suspicion of publication bias (P = 0.50). Our results indicated that 99mTc-MIBI scan is a promising diagnostic modality in predicting the malignancy of lung lesions. PMID:27149482

  15. The Lung Image Database Consortium (LIDC) and Image Database Resource Initiative (IDRI): A Completed Reference Database of Lung Nodules on CT Scans

    SciTech Connect

    2011-02-15

    Purpose: The development of computer-aided diagnostic (CAD) methods for lung nodule detection, classification, and quantitative assessment can be facilitated through a well-characterized repository of computed tomography (CT) scans. The Lung Image Database Consortium (LIDC) and Image Database Resource Initiative (IDRI) completed such a database, establishing a publicly available reference for the medical imaging research community. Initiated by the National Cancer Institute (NCI), further advanced by the Foundation for the National Institutes of Health (FNIH), and accompanied by the Food and Drug Administration (FDA) through active participation, this public-private partnership demonstrates the success of a consortium founded on a consensus-based process. Methods: Seven academic centers and eight medical imaging companies collaborated to identify, address, and resolve challenging organizational, technical, and clinical issues to provide a solid foundation for a robust database. The LIDC/IDRI Database contains 1018 cases, each of which includes images from a clinical thoracic CT scan and an associated XML file that records the results of a two-phase image annotation process performed by four experienced thoracic radiologists. In the initial blinded-read phase, each radiologist independently reviewed each CT scan and marked lesions belonging to one of three categories (''nodule{>=}3 mm,''''nodule<3 mm,'' and ''non-nodule{>=}3 mm''). In the subsequent unblinded-read phase, each radiologist independently reviewed their own marks along with the anonymized marks of the three other radiologists to render a final opinion. The goal of this process was to identify as completely as possible all lung nodules in each CT scan without requiring forced consensus. Results: The Database contains 7371 lesions marked ''nodule'' by at least one radiologist. 2669 of these lesions were marked ''nodule{>=}3 mm'' by at least one radiologist, of which 928 (34.7%) received such marks from

  16. Changes in 99mTechnegas ventilation lung scan in a newborn with absent pulmonary valve syndrome.

    PubMed

    Takahashi, K; Kuwahara, T; Nagatsu, M

    2001-11-01

    A newborn infant with tetralogy of Fallot and absent pulmonary valve was successfully corrected in two stages. Absent pulmonary valve syndrome presenting in early infancy manifests severe respiratory symptoms that still make challenging both management and surgical treatment. This is ascribed to tracheobronchial compression by the extremely dilated pulmonary arteries, and to the resultant pulmonary obstructive lesions. We report herein the first findings of 99mTechnegas ventilation lung scanning in an infant with the syndrome to assess the pulmonary obstructive lesions. PMID:11813924

  17. Comparing algorithms for automated vessel segmentation in computed tomography scans of the lung: the VESSEL12 study.

    PubMed

    Rudyanto, Rina D; Kerkstra, Sjoerd; van Rikxoort, Eva M; Fetita, Catalin; Brillet, Pierre-Yves; Lefevre, Christophe; Xue, Wenzhe; Zhu, Xiangjun; Liang, Jianming; Öksüz, Ilkay; Ünay, Devrim; Kadipaşaoğlu, Kamuran; Estépar, Raúl San José; Ross, James C; Washko, George R; Prieto, Juan-Carlos; Hoyos, Marcela Hernández; Orkisz, Maciej; Meine, Hans; Hüllebrand, Markus; Stöcker, Christina; Mir, Fernando Lopez; Naranjo, Valery; Villanueva, Eliseo; Staring, Marius; Xiao, Changyan; Stoel, Berend C; Fabijanska, Anna; Smistad, Erik; Elster, Anne C; Lindseth, Frank; Foruzan, Amir Hossein; Kiros, Ryan; Popuri, Karteek; Cobzas, Dana; Jimenez-Carretero, Daniel; Santos, Andres; Ledesma-Carbayo, Maria J; Helmberger, Michael; Urschler, Martin; Pienn, Michael; Bosboom, Dennis G H; Campo, Arantza; Prokop, Mathias; de Jong, Pim A; Ortiz-de-Solorzano, Carlos; Muñoz-Barrutia, Arrate; van Ginneken, Bram

    2014-10-01

    The VESSEL12 (VESsel SEgmentation in the Lung) challenge objectively compares the performance of different algorithms to identify vessels in thoracic computed tomography (CT) scans. Vessel segmentation is fundamental in computer aided processing of data generated by 3D imaging modalities. As manual vessel segmentation is prohibitively time consuming, any real world application requires some form of automation. Several approaches exist for automated vessel segmentation, but judging their relative merits is difficult due to a lack of standardized evaluation. We present an annotated reference dataset containing 20 CT scans and propose nine categories to perform a comprehensive evaluation of vessel segmentation algorithms from both academia and industry. Twenty algorithms participated in the VESSEL12 challenge, held at International Symposium on Biomedical Imaging (ISBI) 2012. All results have been published at the VESSEL12 website http://vessel12.grand-challenge.org. The challenge remains ongoing and open to new participants. Our three contributions are: (1) an annotated reference dataset available online for evaluation of new algorithms; (2) a quantitative scoring system for objective comparison of algorithms; and (3) performance analysis of the strengths and weaknesses of the various vessel segmentation methods in the presence of various lung diseases.

  18. Neurologic, neuropsychologic, and computed cranial tomography scan abnormalities in 2- to 10-year survivors of small-cell lung cancer.

    PubMed

    Johnson, B E; Becker, B; Goff, W B; Petronas, N; Krehbiel, M A; Makuch, R W; McKenna, G; Glatstein, E; Ihde, D C

    1985-12-01

    In order to evaluate the relationship between neurologic function and cranial irradiation, 20 patients treated on National Cancer Institute (NCI) small-cell lung cancer (SCLC) trials who were alive and free of cancer 2.4 to 10.6 years (median, 6.2) from the start of therapy were studied. All were tested with a neurologic history and examination, mental status examination, neuropsychologic testing, and review of serial computed cranial tomography (CCT) scans. Fifteen patients had been treated with prophylactic cranial irradiation (PCI), two patients with therapeutic cranial irradiation, and three received no cranial irradiation. All patients but one were ambulatory and none were institutionalized. Fifteen patients (75%) had neurologic complaints, 13 (65%) had abnormal neurologic examinations, 12 (60%) had abnormal mental status examinations, 13 (65%) had abnormal neuropsychologic testing, and 15 (75%) had abnormal CCT scans. Compared with those given low-dose maintenance chemotherapy during PCI using 200 to 300 rad per fraction, patients who were given high-dose induction chemotherapy during the time of cranial irradiation or large radiotherapy fractions (400 rad) were more likely to have abnormal mental status examinations (6/6 v 4/9) and abnormal neuropsychologic tests (6/6 v 4/9), but no major difference in CCT findings was present. CCT scans in the majority of cases (11/18) showed progressive ventricular dilatation or cerebral atrophy up to 8 years after stopping therapy. We conclude neurologic abnormalities are common in long-term survivors of SCLC, and may be more prominent in patients given high-dose chemotherapy during cranial irradiation or treated with large radiotherapy fractions. The CCT scan abnormalities are common and progressive years after prophylactic cranial irradiation and chemotherapy are stopped.

  19. Solitary pulmonary amyloidoma mimicking lung cancer on 18F-FDG PET-CT scan in systemic lupus erythematosus patient.

    PubMed

    Barešić, M; Sreter, K B; Brčić, L; Hećimović, A; Janevski, Z; Anić, B

    2015-12-01

    Localized amyloid deposits (tumoral amyloidosis or amyloidoma) are uncommon form of amyloidosis and nodular pulmonary amyloidomas are rarely found. This incidental finding can mimic a bronchopulmonary neoplasm and may occur secondarily to an infectious, inflammatory or lymphoproliferative disease. We report a case of a 62-year-old female with long-standing systemic lupus erythematosus (SLE) with low compliance who presented with radiologically-verified solitary pulmonary nodule. Work-up included positron emission tomography-computed tomography (PET-CT) scan, which revealed hypermetabolic uptake of (18)F-fluorodeoxyglucose, and lobectomy was performed. Staining of the tissue was positive for Congo red and was green birefringent under polarized light. Immunohistochemical methods excluded lymphoproliferative disease and confirmed amyloidoma. SLE was controlled with antimalarials and glucocorticoids. Pulmonary amyloidoma should be considered in the differential diagnosis of solitary lung nodules.

  20. Lung scintigraphy in differential diagnosis of peripheral lung cancer and community-acquired pneumonia

    NASA Astrophysics Data System (ADS)

    Krivonogov, Nikolay G.; Efimova, Nataliya Y.; Zavadovsky, Konstantin W.; Lishmanov, Yuri B.

    2016-08-01

    Ventilation/perfusion lung scintigraphy was performed in 39 patients with verified diagnosis of community-acquired pneumonia (CAP) and in 14 patients with peripheral lung cancer. Ventilation/perfusion ratio, apical-basal gradients of ventilation (U/L(V)) and lung perfusion (U/L(P)), and alveolar capillary permeability of radionuclide aerosol were determined based on scintigraphy data. The study demonstrated that main signs of CAP were increases in ventilation/perfusion ratio, perfusion and ventilation gradient on a side of the diseased lung, and two-side increase in alveolar capillary permeability rate for radionuclide aerosol. Unlike this, scintigraphic signs of peripheral lung cancer comprise an increase in ventilation/perfusion ratio over 1.0 on a side of the diseased lung with its simultaneous decrease on a contralateral side, normal values of perfusion and ventilation gradients of both lungs, and delayed alveolar capillary clearance in the diseased lung compared with the intact lung.

  1. European survey on the usefulness of /sup 67/Ga lung scans in assessing sarcoidosis. Experience in 14 research centers in seven different countries

    SciTech Connect

    Rizzato, G.; Blasi, A.

    1986-01-01

    Fifty-eight contributors from 12 European and 2 American sarcoidosis centers have collaborated in a survey to define many questions concerning the use of /sup 67/Ga lung scan in sarcoidosis. The new quantitative scoring methods based on digital evaluation seem better in detecting lung activity. In 20.1% of untreated patients, the /sup 67/Ga lung scan appeared to be the only noninvasive method with which clinical activity could be detected. /sup 67/Ga scans may be useful in guiding lung biopsy and in choosing pulmonary segments for BAL. Of 382 patients studied during follow-up (154 patients with three to nine scans at intervals of 2 to 12 months), the /sup 67/Ga scan was far more sensitive than chest radiography, both in detecting improvement and in foreseeing relapses. Steroid therapy appears to suppress ACE levels more than /sup 67/Ga uptake, and /sup 67/Ga uptake more than the alveolitis detectable by BAL. Gallium-67 uptake rebounds to positivity occur in about 40% of patients after steroid discontinuation and in about 20% of patients after steroid reduction to daily doses of 10 mg or less of prednisone. The /sup 67/Ga dose of 1.5 mCi seems appropriate for clinical purposes and is recommended for the subjective scoring method in order to reduce the cost and the radiation burden.

  2. Motion Interplay as a Function of Patient Parameters and Spot Size in Spot Scanning Proton Therapy for Lung Cancer

    SciTech Connect

    Grassberger, Clemens; Dowdell, Stephen; Lomax, Antony; Sharp, Greg; Shackleford, James; Choi, Noah; Willers, Henning; Paganetti, Harald

    2013-06-01

    Purpose: To quantify the impact of respiratory motion on the treatment of lung tumors with spot scanning proton therapy. Methods and Materials: Four-dimensional Monte Carlo simulations were used to assess the interplay effect, which results from relative motion of the tumor and the proton beam, on the dose distribution in the patient. Ten patients with varying tumor sizes (2.6-82.3 cc) and motion amplitudes (3-30 mm) were included in the study. We investigated the impact of the spot size, which varies between proton facilities, and studied single fractions and conventionally fractionated treatments. The following metrics were used in the analysis: minimum/maximum/mean dose, target dose homogeneity, and 2-year local control rate (2y-LC). Results: Respiratory motion reduces the target dose homogeneity, with the largest effects observed for the highest motion amplitudes. Smaller spot sizes (σ ≈ 3 mm) are inherently more sensitive to motion, decreasing target dose homogeneity on average by a factor 2.8 compared with a larger spot size (σ ≈ 13 mm). Using a smaller spot size to treat a tumor with 30-mm motion amplitude reduces the minimum dose to 44.7% of the prescribed dose, decreasing modeled 2y-LC from 87.0% to 2.7%, assuming a single fraction. Conventional fractionation partly mitigates this reduction, yielding a 2y-LC of 71.6%. For the large spot size, conventional fractionation increases target dose homogeneity and prevents a deterioration of 2y-LC for all patients. No correlation with tumor volume is observed. The effect on the normal lung dose distribution is minimal: observed changes in mean lung dose and lung V{sub 20} are <0.6 Gy(RBE) and <1.7%, respectively. Conclusions: For the patients in this study, 2y-LC could be preserved in the presence of interplay using a large spot size and conventional fractionation. For treatments using smaller spot sizes and/or in the delivery of single fractions, interplay effects can lead to significant deterioration of

  3. Motion artifacts occurring at the lung/diaphragm interface using 4D CT attenuation correction of 4D PET scans.

    PubMed

    Killoran, Joseph H; Gerbaudo, Victor H; Mamede, Marcelo; Ionascu, Dan; Park, Sang-June; Berbeco, Ross

    2011-11-15

    For PET/CT, fast CT acquisition time can lead to errors in attenuation correction, particularly at the lung/diaphragm interface. Gated 4D PET can reduce motion artifacts, though residual artifacts may persist depending on the CT dataset used for attenuation correction. We performed phantom studies to evaluate 4D PET images of targets near a density interface using three different methods for attenuation correction: a single 3D CT (3D CTAC), an averaged 4D CT (CINE CTAC), and a fully phase matched 4D CT (4D CTAC). A phantom was designed with two density regions corresponding to diaphragm and lung. An 8 mL sphere phantom loaded with 18F-FDG was used to represent a lung tumor and background FDG included at an 8:1 ratio. Motion patterns of sin(x) and sin4(x) were used for dynamic studies. Image data was acquired using a GE Discovery DVCT-PET/CT scanner. Attenuation correction methods were compared based on normalized recovery coefficient (NRC), as well as a novel quantity "fixed activity volume" (FAV) introduced in our report. Image metrics were compared to those determined from a 3D PET scan with no motion present (3D STATIC). Values of FAV and NRC showed significant variation over the motion cycle when corrected by 3D CTAC images. 4D CTAC- and CINE CTAC-corrected PET images reduced these motion artifacts. The amount of artifact reduction is greater when the target is surrounded by lower density material and when motion was based on sin4(x). 4D CTAC reduced artifacts more than CINE CTAC for most scenarios. For a target surrounded by water equivalent material, there was no advantage to 4D CTAC over CINE CTAC when using the sin(x) motion pattern. Attenuation correction using both 4D CTAC or CINE CTAC can reduce motion artifacts in regions that include a tissue interface such as the lung/diaphragm border. 4D CTAC is more effective than CINE CTAC at reducing artifacts in some, but not all, scenarios.

  4. Telocytes and putative stem cells in the lungs: electron microscopy, electron tomography and laser scanning microscopy.

    PubMed

    Popescu, Laurentiu M; Gherghiceanu, Mihaela; Suciu, Laura C; Manole, Catalin G; Hinescu, Mihail E

    2011-09-01

    This study describes a novel type of interstitial (stromal) cell - telocytes (TCs) - in the human and mouse respiratory tree (terminal and respiratory bronchioles, as well as alveolar ducts). TCs have recently been described in pleura, epicardium, myocardium, endocardium, intestine, uterus, pancreas, mammary gland, etc. (see www.telocytes.com ). TCs are cells with specific prolongations called telopodes (Tp), frequently two to three per cell. Tp are very long prolongations (tens up to hundreds of μm) built of alternating thin segments known as podomers (≤ 200 nm, below the resolving power of light microscope) and dilated segments called podoms, which accommodate mitochondria, rough endoplasmic reticulum and caveolae. Tp ramify dichotomously, making a 3-dimensional network with complex homo- and heterocellular junctions. Confocal microscopy reveals that TCs are c-kit- and CD34-positive. Tp release shed vesicles or exosomes, sending macromolecular signals to neighboring cells and eventually modifying their transcriptional activity. At bronchoalveolar junctions, TCs have been observed in close association with putative stem cells (SCs) in the subepithelial stroma. SCs are recognized by their ultrastructure and Sca-1 positivity. Tp surround SCs, forming complex TC-SC niches (TC-SCNs). Electron tomography allows the identification of bridging nanostructures, which connect Tp with SCs. In conclusion, this study shows the presence of TCs in lungs and identifies a TC-SC tandem in subepithelial niches of the bronchiolar tree. In TC-SCNs, the synergy of TCs and SCs may be based on nanocontacts and shed vesicles.

  5. Leg scanning with radioisotope-labeled fibrinogen in patients undergoing hip surgery

    SciTech Connect

    LeMoine, J.R.; Moser, K.M.

    1980-05-01

    To establish whether radioisotope-labeled fibrinogen leg scanning is of value in the context of hip surgery, we propsectively studied 21 consectuvie patients undergoing either total hip replacement (14) or open repair of a hip fracture (seven) with leg scans, contrast phlebography, and ventilation and perfusion lung scans. We found that in eight patients (38%), venous thromboembolism developed postoperatively. Agreement between phlebographic and leg scanning results was excellent. In no patient as venous thrombosis limited to the thigh on the operated-on side, a vital consideration in application of fibrinogen leg scanning to this patient population. Two patients had lung scan changes indicative of embolism; both had thrombi extending into thigh veins. Leg scanning with radioisotope-labeled fibrinogen appears to be a useful method for monitoring patients undergoing hip surgery, if the upper three counting points on the operated-on side are excluded.

  6. Perfusion visualization and analysis for pulmonary embolism

    NASA Astrophysics Data System (ADS)

    Vaz, Michael S.; Kiraly, Atilla P.; Naidich, David P.; Novak, Carol L.

    2005-04-01

    Given the nature of pulmonary embolism (PE), timely and accurate diagnosis is critical. Contrast enhanced high-resolution CT images allow physicians to accurately identify segmental and sub-segmental emboli. However, it is also important to assess the effect of such emboli on the blood flow in the lungs. Expanding upon previous research, we propose a method for 3D visualization of lung perfusion. The proposed method allows users to examine perfusion throughout the entire lung volume at a single glance, with areas of diminished perfusion highlighted so that they are visible independent of the viewing location. This may be particularly valuable for better accuracy in assessing the extent of hemodynamic alterations resulting from pulmonary emboli. The method also facilitates user interaction and may help identify small peripheral sub-segmental emboli otherwise overlooked. 19 patients referred for possible PE were evaluated by CT following the administration of IV contrast media. An experienced thoracic radiologist assessed the 19 datasets with 17 diagnosed as being positive for PE with multiple emboli. Since anomalies in lung perfusion due to PE can alter the distribution of parenchymal densities, we analyzed features collected from histograms of the computed perfusion maps and demonstrate their potential usefulness as a preliminary test to suggest the presence of PE. These histogram features also offer the possibility of distinguishing distinct patterns associated with chronic PE and may even be useful for further characterization of changes in perfusion or overall density resulting from associated conditions such as pneumonia or diffuse lung disease.

  7. The added value of hybrid ventilation/perfusion SPECT/CT in patients with stable COPD or apparently healthy smokers. Cancer-suspected CT findings in the lungs are common when hybrid imaging is used.

    PubMed

    Jögi, Jonas; Markstad, Hanna; Tufvesson, Ellen; Bjermer, Leif; Bajc, Marika

    2015-01-01

    Ventilation/perfusion (V/P) single-photon emission computed tomography (SPECT) is recognized as a diagnostic method with potential beyond the diagnosis of pulmonary embolism. V/P SPECT identifies functional impairment in diseases such as heart failure (HF), pneumonia, and chronic obstructive pulmonary disease (COPD). The development of hybrid SPECT/computed tomography (CT) systems, combining functional with morphological imaging through the addition of low-dose CT (LDCT), may be useful in COPD, as these patients are prone to lung cancer and other comorbidities. The aim of this study was to investigate the added value of LDCT among healthy smokers and patients with stable COPD, when examined with V/P SPECT/CT hybrid imaging. Sixty-nine subjects, 55 with COPD (GOLD I-IV) and 14 apparently healthy smokers, were examined with V/P SPECT and LDCT hybrid imaging. Spirometry was used to verify COPD grade. Only one apparently healthy smoker and three COPD patients had a normal or nearly normal V/P SPECT. All other patients showed various degrees of airway obstruction, even when spirometry was normal. The same interpretation was reached on both modalities in 39% of the patients. LDCT made V/P SPECT interpretation more certain in 9% of the patients and, in 52%, LDCT provided additional diagnoses. LDCT better characterized the type of emphysema in 12 patients. In 19 cases, tumor-suspected changes were reported. Three of these 19 patients (ie, 4.3% of all subjects) were in the end confirmed to have lung cancer. The majority of LDCT findings were not regarded as clinically significant. V/P SPECT identified perfusion patterns consistent with decompensated left ventricular HF in 14 COPD patients. In 16 patients (23%), perfusion defects were observed. HF and perfusion defects were not recognized with LDCT. In COPD patients and long-time smokers, hybrid imaging had added value compared to V/P SPECT alone, by identifying patients with lung malignancy and more clearly identifying

  8. The added value of hybrid ventilation/perfusion SPECT/CT in patients with stable COPD or apparently healthy smokers. Cancer-suspected CT findings in the lungs are common when hybrid imaging is used.

    PubMed

    Jögi, Jonas; Markstad, Hanna; Tufvesson, Ellen; Bjermer, Leif; Bajc, Marika

    2015-01-01

    Ventilation/perfusion (V/P) single-photon emission computed tomography (SPECT) is recognized as a diagnostic method with potential beyond the diagnosis of pulmonary embolism. V/P SPECT identifies functional impairment in diseases such as heart failure (HF), pneumonia, and chronic obstructive pulmonary disease (COPD). The development of hybrid SPECT/computed tomography (CT) systems, combining functional with morphological imaging through the addition of low-dose CT (LDCT), may be useful in COPD, as these patients are prone to lung cancer and other comorbidities. The aim of this study was to investigate the added value of LDCT among healthy smokers and patients with stable COPD, when examined with V/P SPECT/CT hybrid imaging. Sixty-nine subjects, 55 with COPD (GOLD I-IV) and 14 apparently healthy smokers, were examined with V/P SPECT and LDCT hybrid imaging. Spirometry was used to verify COPD grade. Only one apparently healthy smoker and three COPD patients had a normal or nearly normal V/P SPECT. All other patients showed various degrees of airway obstruction, even when spirometry was normal. The same interpretation was reached on both modalities in 39% of the patients. LDCT made V/P SPECT interpretation more certain in 9% of the patients and, in 52%, LDCT provided additional diagnoses. LDCT better characterized the type of emphysema in 12 patients. In 19 cases, tumor-suspected changes were reported. Three of these 19 patients (ie, 4.3% of all subjects) were in the end confirmed to have lung cancer. The majority of LDCT findings were not regarded as clinically significant. V/P SPECT identified perfusion patterns consistent with decompensated left ventricular HF in 14 COPD patients. In 16 patients (23%), perfusion defects were observed. HF and perfusion defects were not recognized with LDCT. In COPD patients and long-time smokers, hybrid imaging had added value compared to V/P SPECT alone, by identifying patients with lung malignancy and more clearly identifying

  9. Open lung biopsy

    MedlinePlus

    Biopsy - open lung ... An open lung biopsy is done in the hospital using general anesthesia , which means you are asleep and pain- ... The open lung biopsy is done to evaluate lung problems seen on x-ray or CT scan .

  10. A risk assessment of multiple use of an aerosol system compared with single use for lung ventilation scans.

    PubMed

    Belton, I P; Burford, D; Early, M Y

    1997-07-01

    Over 300 99Tc(m)-DTPA aerosol lung ventilation scans are performed at Leicester Royal Infirmary each year. Current practice is to re-use the nebulizer circuits up to five times over a maximum of 1 week. Following a visit from the hospital infection control team, this practice was questioned and, therefore, a risk assessment was carried out. This compared the risks of multiple use of ventilation circuits with single use. A survey was also carried out to try and establish current practice in other departments. The risk assesment showed that both single and multiple use of nebulizer circuits can have a high risk. The risks associated with the former were radiation safety and/or financial, and the risk with the latter was cross-infection. The survey showed that multiple use is certainly common practice within the UK. Therefore, in coming to a decision on which practice to adopt, these risks must be considered most carefully in the context of the local environment.

  11. Low local blood perfusion, high white blood cell and high platelet count are associated with primary tumor growth and lung metastasis in a 4T1 mouse breast cancer metastasis model

    PubMed Central

    WANG, CHUAN; CHEN, YING-GE; GAO, JIAN-LI; LYU, GUI-YUAN; SU, JIE; ZHANG, QI; JI, XIN; YAN, JI-ZHONG; QIU, QIAO-LI; ZHANG, YUE-LI; LI, LIN-ZI; XU, HAN-TING; CHEN, SU-HONG

    2015-01-01

    It was originally thought that no single routine blood test result would be able to indicate whether or not a patient had cancer; however, several novel studies have indicated that the median survival and prognosis of cancer patients were markedly associated with the systemic circulation features of cancer patients. In addition, certain parameters, such as white blood cell (WBC) count, were largely altered in malignant tumors. In the present study, routine blood tests were performed in order to observe the change of blood cells in tumor-bearing mice following the implantation of 4T1 breast cancer cells into the mammary fat pad; in addition, blood flow in breast tumor sites was measured indirectly using laser Doppler perfusion imaging (LDPI), in an attempt to explain the relevance between the blood circulation features and the growth or metastasis of breast cancer in mice model. The LDPI and blood test results indicated that the implantation of 4T1 breast cancer cells into BALB/c mice led to thrombosis as well as high WBC count, high platelet count, high plateletcrit and low blood perfusion. Following implantation of the 4T1 cells for four weeks, the lung metastatic number was determined and the Pearson correlation coefficient revealed that the number of visceral lung metastatic sites had a marked negative association with the ratio of basophils (BASO%; r=-0.512; P<0.01) and the mean corpuscular hemoglobin was significantly correlated with primary tumor weight (r=0.425; P<0.05). In conclusion, the results of the present study demonstrated that tumor growth led to thrombosis and acute anemia in mice; in addition, when blood BASO% was low, an increased number of lung metastases were observed in tumor-bearing mice. PMID:26622565

  12. Indeterminate lung imaging. Can the number be reduced

    SciTech Connect

    Davis, R.B.; Schauwecker, D.S.; Siddiqui, A.R.; Becker, G.J.; Holden, R.W.; Richmond, B.D.; Wellman, H.N.

    1986-08-01

    During a 2 1/2-year period, 1131 patients with suspected pulmonary embolism had ventilation-perfusion lung scans; 150 of these patients also underwent pulmonary angiography. In a retrospective study, these 150 patients were re-evaluated using the reference criteria of Biello and Alderson, with 62% read as indeterminate. Twenty patients who had chronic obstructive pulmonary disease with retention of Xe-133 in greater than 50% of the lung fields without corresponding radiographic abnormality were included. Ventilation/perfusion matches and mismatches could be correctly determined in 15 of these patients. These 15 of 20 studies could be correctly reclassified as low-probability, while the other five remained indeterminate. With increasing intervals between ventilation/perfusion lung imaging and the onset of symptoms, the percentage of patients with proven pulmonary emboli correctly diagnosed as high probability continuously decreased, and the percentage of studies read as indeterminate constantly increased. Serial chest radiographs suggested that the development of infiltrates in the region of the embolus convert high-probability ventilation/perfusion scans to indeterminate.

  13. A case of hut lung: scanning electron microscopy with energy dispersive x-ray spectroscopy analysis of a domestically acquired form of pneumoconiosis.

    PubMed

    Mukhopadhyay, Sanjay; Gujral, Manmeet; Abraham, Jerrold L; Scalzetti, Ernest M; Iannuzzi, Michael C

    2013-07-01

    Hut lung is a pneumoconiosis caused by exposure to smoke derived from biomass fuels used for cooking in poorly ventilated huts. We report, to our knowledge, the first analysis of the dust deposited in the lungs in hut lung by scanning electron microscopy with energy dispersive x-ray spectroscopy (SEM/EDS). A Bhutanese woman presented with shortness of breath and an abnormal chest radiograph. Chest CT scan showed innumerable tiny bilateral upper lobe centrilobular nodules. Transbronchial biopsy revealed mild interstitial fibrosis with heavy interstitial deposition of black dust. SEM/EDS showed that the dust was carbonaceous, with smaller yet substantial numbers of silica and silicate particles. Additional history revealed use of a wood/coal-fueled stove in a small, poorly ventilated hut for 45 years. The possibility of hut lung should be considered in women from countries where use of biomass-fueled stoves for cooking is common. Our findings support the classification of this condition as a mixed-dust pneumoconiosis.

  14. Lung uptake of thallium-201: a marker of defect reversibility?

    NASA Astrophysics Data System (ADS)

    Sanderson, R.; Woldman, S.; McCurrach, G.; Martin, W.; Hutton, I.

    1998-06-01

    High lung uptake of thallium-201 at stress is reported to be associated with a large number of perfusion defects and poor prognosis. This study was performed to assess whether the reversibility of stress perfusion defects was related to lung uptake. Gated planar thallium scans at stress and at redistribution from 102 consecutive patients with essentially normal left ventricular ejection fraction (using gated blood pool ventriculography) were graded in terms of defect size. Lung and myocardial uptake of thallium were quantitated by region of interest methods relative to the given activity in a previously validated method. There was no significant correlation (non-parametric) between lung uptake and degree of redistribution (). There was a weak but positive correlation between lung uptake and defect size (). Both exercise time and double product showed a negative correlation with lung uptake (e.g. for double product, ). In conclusion, contrary to our expectation, lung uptake is not related to the degree of redistribution. High lung uptake seems to reflect poor cardiovascular reserve.

  15. Angina Relief by Ranolazine Identifies False-Negative SPECT Myocardial Perfusion Scans in Patients with Coronary Disease Demonstrated by Coronary Angiography

    PubMed Central

    Murray, Gary L.

    2014-01-01

    Normal myocardial perfusion imaging (MPI) reduces intermediate- or high-risk pretest probability patients to low- or intermediate-risk posttest probability, respectively, for coronary disease (CD). Since ranolazine (RAN) relieves only angina, anginal patients with normal MPI whose angina is relieved by RAN present a significant dilemma. The purpose of this retrospective chart review was to confirm the impression that coronary angiography (CA) is indicated in patients whose class 3 to 4 angina is relieved by RAN, but have normal myocardial single-photon emission computed tomography (SPECT) MPIs. Charts of patients with stable class 3 to 4 angina (typical and atypical) and normal MPIs (left ventricular ejection fraction [LVEF] ≥50% and segmental score = 0) were reviewed. CA was done on all the patients with complete angina relief taking RAN, as well as nonresponders whose anginal etiology could not be explained. Stenoses were considered flow-restrictive when more than 70% diameter stenosis is observed by quantitative CA, or, when 50 to 70%, fractional flow reserve (FFR) measured ≤0.80. RAN relieved angina in 36 of 54 (67%) patients. Of the known cases, 25 of these 36 (69%) had 43 stenoses ≥50% (mean = 66%): 15 (60%) had 1 vessel disease; 9 (36%) had multivessel disease; 18 (72%) had left anterior descending (LAD) disease; 1 (4%) had left main disease. Twenty one of 43 (49%) stenosis were > 70%; 22 (51%) stenoses were 50 to 70% and required FFR measurement. Twenty nine of 43 stenoses (67%) were considered flow-restrictive in 18 of these 25 (72%) patients. Eight RAN nonresponders with no explanation for angina had no CD at CA. RAN angina relief is invaluable in identifying falsely negative SPECT MPI, and 50% of these patients have flow-restrictive stenoses. PMID:25317027

  16. The Role of Routine Whole Volume SPECT Reconstruction in Comparison to Cine Raw Data in the Detection of Extracardiac Uptake on Myocardial Perfusion Scans.

    PubMed

    Maharaj, M; Korowlay, N A

    2011-01-01

    The objective of this study was to determine the role of routine whole volume reconstructed single-photon emission tomography (rSPECT) compared to cine raw data to detect extracardiac uptake of Sestamibi (MIBI). In a retrospective study, the myocardial perfusion studies of 426 patients were inspected separately for extracardiac uptake on cine raw data and rSPECT. The acquisition parameters for all the images were done according to departmental protocol. The whole volume SPECT data was selected and processed by HOSEM iterative reconstruction using the HERMES computer software system. The images were assessed by two observers, a student in training and a senior consultant nuclear medicine physician. The overall mean age and standard deviation of the 426 patients at the time of the study was 60 ± 12 years. Statistical analysis was performed using the Kappa and McNemars tests. The clinical significance of the extracardiac uptake was evaluated using hospital folders and /or laboratory results after viewing images. rSPECT detected 25 patients (5.9%) and cine raw data identified 18 patients (4.2%) with extracardiac uptake. All the areas of extracardiac uptake noted on cine raw data were seen on the rSPECT images. Only 21 of the 25 patients had complete 5-year clinical follow-up. The value of the clinical significance of the extracardiac uptake was limited due to the study being retrospective. The proportion of positives identified by rSPECT was significantly larger than those identified by cine raw data (P = 0.0082). Although our study demonstrates that rSPECT is more sensitive than cine raw data in detecting extracardiac uptake, it also shows that there is no benefit in routine whole volume rSPECT in daily clinical practice.

  17. Predicting language improvement in acute stroke patients presenting with aphasia: a multivariate logistic model using location-weighted atlas-based analysis of admission CT perfusion scans

    PubMed Central

    Payabvash, Seyedmehdi; Kamalian, Shahmir; Fung, Steve; Wang, Yifei; Passanese, John; Kamalian, Shervin; Souza, Leticia CS; Kemmling, Andre; Harris, Gordon J.; Halpern, Elkan F.; Gonzalez, R. Gilberto; Furie, Karen L.; Lev, Michael H.

    2013-01-01

    Purpose To construct a multivariate model for prediction of early aphasia improvement in stroke patients using admission CT perfusion (CTP) and CT angiography (CTA). Methods Fifty-eight consecutive patients with aphasia due to first-time ischemic stroke of the left hemisphere were included. Language function was assessed based on patients’ admission and discharge NIHSS and clinical records. All patients had brain CTP and CTA within 9 hours of symptom onset. For image analysis, all CTPs were automatically coregistered to MNI-152 brain space and parcellated into mirrored cortical and subcortical regions. Multiple logistic regression analysis was used to find independent imaging and clinical predictors of language recovery. Results By the time of discharge, 21 (36%) patients demonstrated improvement of language. Independent factors predicting improvement in language included relative cerebral blood flow of angular gyrus gray matter (Brodmann’s area 39) and lower third of insular ribbon, proximal cerebral artery occlusion on admission CTA, and aphasia score on admission NIHSS exam. Using these 4 variables, we developed a multivariate logistic regression model that could estimate the probability of early improvement in stroke patients presenting with aphasia and predict functional outcome with 91% accuracy. Conclusion An imaging-based location weighted multivariate model is developed to predict early language improvement of aphasic patients using admission data collected within 9-hours of stroke onset. This pilot model should be validated in a larger, prospective study; however, the semi-automated atlas-based analysis of brain CTP, along with the statistical approach, could be generalized for prediction of other outcome measures in stroke patients. PMID:20488905

  18. Krypton 81m ventilation/perfusion ratios (V/Q) measured in lateral decubitus in pulmonary embolism (P. E. )

    SciTech Connect

    Meignan, M.; Cinotti, L.; Harf, A.; Oliveira, L.; Simonneau, G.

    1984-01-01

    In normal subjects lateral decubitis induces in both independent (lower) and nondependent lung (upper), major changes in perfusion, ventilation and V/Q ratios which can be studied with the short life radioisotope Krypton 81m. Regional V/Q are computed from ventilation and perfusion scans, successively obtained with a gamma camera linked to a computer by continuous inhalation or infusion of this gas during tidal breathing. They were displayed as a color coded functional image. To assess the effect of posture on V/Q in P.E. and other diseases which decrease the regional perfusion, 32 patients with unilateral lung diseases were studied in supine posture and both lateral decubitis: 8 with proved P.E., (3 out of them having radiological opacity matching the perfusion defect), 9 with bullous emphysema, 6 with bronchogenic carcinoma, 9 with acute bacterial pneumonia. V/Q were computed in the region of the perfusion defect. In P.E. the mean V/Q was high (1.92 +- 0.6 SD), and did not change whatever the posture. Conversely major changes of V/Q were induced with postural changes in bullous emphysema and lung carcinoma whatever the V/Q in patient supine. In pneumonia low V/Q were observed in supine posture (.73 +- .2). They decreased significantly when the pneumonia was dependent (.53 +- .2 p < 0.02) and increased in the controlateral decubitis (1.07 +- .3, p < 0.001). Since posture has no or little effect on regional V/Q in P.E., it can be used to discriminate P.E., even in the case of radiological opacity, from other unilateral disease inducing perfusion defect.

  19. SU-E-J-113: Effects of Deformable Registration On First-Order Texture Maps Calculated From Thoracic Lung CT Scans

    SciTech Connect

    Smith, C; Cunliffe, A; Al-Hallaq, H; Armato, S

    2015-06-15

    Purpose: To determine the stability of eight first-order texture features following the deformable registration of serial computed tomography (CT) scans. Methods: CT scans at two different time points from 10 patients deemed to have no lung abnormalities by a radiologist were collected. Following lung segmentation using an in-house program, texture maps were calculated from 32×32-pixel regions of interest centered at every pixel in the lungs. The texture feature value of the ROI was assigned to the center pixel of the ROI in the corresponding location of the texture map. Pixels in the square ROI not contained within the segmented lung were not included in the calculation. To quantify the agreement between ROI texture features in corresponding pixels of the baseline and follow-up texture maps, the Fraunhofer MEVIS EMPIRE10 deformable registration algorithm was used to register the baseline and follow-up scans. Bland-Altman analysis was used to compare registered scan pairs by computing normalized bias (nBias), defined as the feature value change normalized to the mean feature value, and normalized range of agreement (nRoA), defined as the range spanned by the 95% limits of agreement normalized to the mean feature value. Results: Each patient’s scans contained between 6.8–15.4 million ROIs. All of the first-order features investigated were found to have an nBias value less than 0.04% and an nRoA less than 19%, indicating that the variability introduced by deformable registration was low. Conclusion: The eight first-order features investigated were found to be registration stable. Changes in CT texture maps could allow for temporal-spatial evaluation of the evolution of lung abnormalities relating to a variety of diseases on a patient-by-patient basis. SGA and HA receives royalties and licensing fees through the University of Chicago for computer-aided diagnosis technology. Research reported in this publication was supported by the National Institute Of General

  20. Changes in Functional Lung Regions During the Course of Radiation Therapy and Their Potential Impact on Lung Dosimetry for Non-Small Cell Lung Cancer

    SciTech Connect

    Meng, Xue; Frey, Kirk; Matuszak, Martha; Paul, Stanton; Ten Haken, Randall; Yu, Jinming; Kong, Feng-Ming

    2014-05-01

    Purpose: To study changes in functional activity on ventilation (V)/perfusion (Q) single-photon emission computed tomography (SPECT) during radiation therapy (RT) and explore the impact of such changes on lung dosimetry in patients with non-small cell lung cancer (NSCLC). Methods and Materials: Fifteen NSCLC patients with centrally located tumors were enrolled. All patients were treated with definitive RT dose of ≥60 Gy. V/Q SPECT-CT scans were performed prior to and after delivery of 45 Gy of fractionated RT. SPECT images were used to define temporarily dysfunctional regions of lung caused by tumor or other potentially reversible conditions as B3. The functional lung (FL) was defined on SPECT by 2 separate approaches: FL1, a threshold of 30% of the maximum uptake of the patient's lung; and FL2, FL1 plus B3 region. The impact of changes in FL between initiation of RT and delivery of 45 Gy on lung dosimetry were analyzed. Results: Fourteen patients (93%) had larger FL2 volumes than FL1 pre-RT (P<.001). Dysfunctional lung became functional in 11 patients (73%) on V SPECT and in 10 patients (67%) on Q SPECT. The dosimetric parameters generated from CT-based anatomical lung had significantly lower values in FL1 than FL2, with a median reduction in the volume of lung receiving a dose of at least 20 Gy (V{sub 20}) of 3%, 5.6%, and mean lung dose of 0.95 and 1.55 on V and Q SPECT respectively. Conclusions: Regional ventilation and perfusion function improve significantly during RT in centrally located NSCLC. Lung dosimetry values vary notably between different definitions of functional lung.

  1. Usefulness of target delineation based on the two extreme phases of a four-dimensional computed tomography scan in stereotactic body radiation therapy for lung cancer

    PubMed Central

    Jang, Seong Soon; Huh, Gil Ja; Park, Suk Young; Yang, Po Song; Cho, EunYoun

    2015-01-01

    Background An evaluation of the usefulness of target delineation based only on the two extreme phases of a four-dimensional computed tomography (4D CT) scan in lung stereotactic body radiation therapy (SBRT). Methods Seventeen patients treated with SBRT via 4D CT scans for lung cancer were retrospectively enrolled. Volumetric and geometric analyses were performed for the internal target volumes (ITVs) and planning target volumes (PTVs) generated using different respiratory phases (all phases and 2 extreme phases) and setup margins (3 mm and 5 mm). Results As the setup margins were added to the ITVs, the overlap percentage between the PTVs based on all phases and the two extreme phases increased (85.1% for ITVs, 89.8% for PTVs_3 mm, and 91.3% for PTVs_5 mm), and there were no differences according to the tumor parameters, such as the gross tumor volume and 3D mobility. The missing-volume differences for ITVs derived from cone-beam CT images also decreased, with values of 5.3% between ITVs, 0.5% between PTVs_3 mm, and 0.2% between PTVs_5 mm. Compared with the plan based on all phases and a 3 mm margin, the average lung-dose differences found for the PTV based on the two extreme phases and a 5 mm margin were 0.41 Gy for the mean lung dose and 0.93% for V20. Conclusions Regardless of tumor characteristics, PTV construction based only on the two extreme phases and a 5 mm setup margin may be a useful tool for reducing the clinical workload involved in target delineation in SBRT for lung cancer. PMID:26273368

  2. Advances in functional and structural imaging of the human lung using proton MRI.

    PubMed

    Miller, G Wilson; Mugler, John P; Sá, Rui C; Altes, Talissa A; Prisk, G Kim; Hopkins, Susan R

    2014-12-01

    The field of proton lung MRI is advancing on a variety of fronts. In the realm of functional imaging, it is now possible to use arterial spin labeling (ASL) and oxygen-enhanced imaging techniques to quantify regional perfusion and ventilation, respectively, in standard units of measurement. By combining these techniques into a single scan, it is also possible to quantify the local ventilation-perfusion ratio, which is the most important determinant of gas-exchange efficiency in the lung. To demonstrate potential for accurate and meaningful measurements of lung function, this technique was used to study gravitational gradients of ventilation, perfusion, and ventilation-perfusion ratio in healthy subjects, yielding quantitative results consistent with expected regional variations. Such techniques can also be applied in the time domain, providing new tools for studying temporal dynamics of lung function. Temporal ASL measurements showed increased spatial-temporal heterogeneity of pulmonary blood flow in healthy subjects exposed to hypoxia, suggesting sensitivity to active control mechanisms such as hypoxic pulmonary vasoconstriction, and illustrating that to fully examine the factors that govern lung function it is necessary to consider temporal as well as spatial variability. Further development to increase spatial coverage and improve robustness would enhance the clinical applicability of these new functional imaging tools. In the realm of structural imaging, pulse sequence techniques such as ultrashort echo-time radial k-space acquisition, ultrafast steady-state free precession, and imaging-based diaphragm triggering can be combined to overcome the significant challenges associated with proton MRI in the lung, enabling high-quality three-dimensional imaging of the whole lung in a clinically reasonable scan time. Images of healthy and cystic fibrosis subjects using these techniques demonstrate substantial promise for non-contrast pulmonary angiography and detailed

  3. Prediction of multivessel coronary artery disease and prognosis early after acute myocardial infarction by exercise electrocardiography and thallium-201 myocardial perfusion scanning

    SciTech Connect

    Abraham, R.D.; Freedman, S.B.; Dunn, R.F.; Newman, H.; Roubin, G.S.; Harris, P.J.; Kelly, D.T.

    1986-09-01

    Exercise electrocardiography and thallium scanning were performed a mean of 24 days after uncomplicated acute myocardial infarction in 103 patients, aged 36 to 60 years, who also underwent coronary angiography. The purpose of the study was to determine the ability of the noninvasive tests to predict multivessel coronary artery disease (CAD) and prognosis. Patients were followed up to document medical complications (incidence 12%: 3 deaths, 1 resuscitated cardiac arrest, 4 recurrent infarctions, 4 admissions with unstable angina) and combined events (medical events or bypass surgery, incidence 23%). The sensitivity, specificity and predictive accuracy for predicting multivessel CAD were 64%, 77% and 64% for a positive exercise electrocardiographic (ECG) response, 64%, 88% and 80% for a remote thallium defect, and 42%, 96% and 88% for a combination of the 2 tests. With 2 tests yielding negative findings the probability of multivessel CAD was 13%. No variable (positive exercise ECG response, remote thallium defect and presence of multivessel CAD) predicted medical events, although there were nonsignificant trends to more events in patients with any of those findings. The relative risk of combined events was 2.5 (p less than 0.05) for a positive exercise ECG response; 1.8 (NS) for a remote thallium defect; 2.6 (p less than 0.05) for multivessel CAD; and 3.1 (p less than 0.025) for both positive ECG response and remote defect. A combination of exercise electrocardiography and thallium scanning early after acute myocardial infarction helps to identify subsets of patients with high and low probabilities of multivessel CAD and combined medical or surgical events.

  4. Kr-81m for both ventilation and perfusion from one generator

    SciTech Connect

    Webber, M.M.; Gong, H.; Ertle, A.R.

    1984-01-01

    This paper describes a new technique which utilizes a single generator to provide both gaseous Kr-81m for ventilation and Kr-81m dissolved in water for perfusion lung images. Commercially available Krypton 81m gas generators provide Kr-81m in the gas form only, by air elution. Also available on an experimental basis is a small generator which by water elution provides Kr-81m in a soluble form suitable for perfusion lung scans. The small generator used for soluble form of Krypton is only approximately 1/8 inch in diameter by about 1 inch in length. A patient could not breath through it easily and quickly enough to achieve a deep single breath necessary for imaging. In order to overcome this problem the authors designed a system in which the patient breathes through a large spirometry tube, 1 1/2 in diameter by 2 feet long. The small generator is prepared for use by flushing out the water, 5 ml of sterile air is drawn into a syringe using an 18 gauge needle. The patient then places the end of the large tube in his mouth, and is asked to take a deep breath and to hold it. As the patient takes the breath an injection of the sterile air is made into the lumen of the large tube, passing through the small generator en route. The injection of air continues as the patient takes his breath. The method, although only requiring the small generator which can be used for perfusion lung scans as well as ventilation scans, consistently provides good results.

  5. The morphology of the lung of the African lungfish, Protopterus aethiopicus : A scanning electron-microscopic study.

    PubMed

    Maina, J N

    1987-10-01

    The lung of the African lungfish (Protopterus aethiopicus) is paired, long and cylindrical. It is situated on the dorsal aspect of the coelomic cavity ventral to the ribs. Much of the gas exchange tissue is found in the proximal aspect of the lung with the caudal part largely taken up by a centrally situated air-duct with a few large peripherally located alveoli. Interalveolar septa, arranged at differing hierarchical levels from the air-duct, subdivide the lung into alveoli, the gas exchange compartments. The alveolar surface is covered by some cells characterized by microvilli on their free surface, while others are devoid of such structures. The general organization of the lung of Protopterus aethiopicus is similar to that of the other genera of Dipnoi, Neoceratodus and Lepidosiren, with the interalveolar septa increasing the surface area for gas exchange through pulmonary compartmentation. The abundant septal smooth muscle fibres and elastic tissue may contribute to the physiomechanical compliance of the lung. The undifferentiated alveolar pneumocytes and the double capillary system, observed in Protopterus, in general appear to characterize the very primitive lungs of the lower air-breathing vertebrates. PMID:21253769

  6. Microfluidic perfusion culture.

    PubMed

    Hattori, Koji; Sugiura, Shinji; Kanamori, Toshiyuki

    2014-01-01

    Microfluidic perfusion culture is a novel technique to culture animal cells in a small-scale microchamber with medium perfusion. Polydimethylsiloxane (PDMS) is the most popular material to fabricate a microfluidic perfusion culture chip. Photolithography and replica molding techniques are generally used for fabrication of a microfluidic perfusion culture chip. Pressure-driven perfusion culture system is convenient technique to carry out the perfusion culture of animal cells in a microfluidic device. Here, we describe a general theory on microfluid network design, microfabrication technique, and experimental technique for pressure-driven perfusion culture in an 8 × 8 microchamber array on a glass slide-sized microchip made out of PDMS. PMID:24297421

  7. The morphology of the lung of the black mamba Dendroaspis polylepis (Reptilia: Ophidia: Elapidae). A scanning and transmission electron microscopic study.

    PubMed Central

    Maina, J N

    1989-01-01

    The lung of a snake, the black mamba (Dendroaspis polylepis), has been investigated by scanning and transmission electron microscopy. This species has only one lung, the right, which is long and occupies most of the pleuro-peritoneal cavity. Grossly, the lung could be divided into two discrete anatomical regions: an anterior respiratory area made up of a honeycomb network of capillary-bearing partitions, and a posterior membranous saccular region. The exchange region consisted of a central air duct, the bronchus, which was delineated both dorsally and laterally by morphologically and spatially distinct hierarchically arranged septa. The primary septa gave rise to the secondary septa from which the much deeper peripherally situated tertiary septa that formed the immediate openings to the faveoli arose. The faveoli were rather parallel elongated pockets separated by partitions, the interfaveolar septa, and terminated peripherally on the pleura. A double capillary disposition of the blood capillaries was observed on the relatively thick primary and secondary septa. These septa were lined by a heterogenous epithelium made up of ciliated cells, secretory cells, and smooth squamous cells. This epithelium was continued from the trachea and the bronchus. At the faveolar level the blood capillaries exhibited a single system where they formed a matrix on both sides of the partitions. The surface of the faveoli was covered by two types of cells: Type I cells were squamous and their remarkably attenuated cytoplasmic arborisations were notably extensive while the Type II cells were rather cuboidal, bore stubby microvilli and contained the characteristic osmiophilic lamellated bodies. On the basis of the clearly evident complete differentiation of the pneumocytes and the presence of both the double and single capillary systems, it was observed that this lung, and apparently the reptilian lung in general, manifests a transitional developmental and structural stage in the

  8. TU-A-12A-04: Quantitative Texture Features Calculated in Lung Tissue From CT Scans Demonstrate Consistency Between Two Databases From Different Institutions

    SciTech Connect

    Cunliffe, A; Armato, S; Castillo, R; Pham, N; Guerrero, T; Al-Hallaq, H

    2014-06-15

    Purpose: To evaluate the consistency of computed tomography (CT) scan texture features, previously identified as stable in a healthy patient cohort, in esophageal cancer patient CT scans. Methods: 116 patients receiving radiation therapy (median dose: 50.4Gy) for esophageal cancer were retrospectively identified. For each patient, diagnostic-quality pre-therapy (0-183 days) and post-therapy (5-120 days) scans (mean voxel size: 0.8mm×0.8mm×2.5mm) and a treatment planning scan and associated dose map were collected. An average of 501 32x32-pixel ROIs were placed randomly in the lungs of each pre-therapy scan. ROI centers were mapped to corresponding locations in post-therapy and planning scans using the displacement vector field output by demons deformable registration. Only ROIs with mean dose <5Gy were analyzed, as these were expected to contain minimal post-treatment damage. 140 texture features were calculated in pre-therapy and post-therapy scan ROIs and compared using Bland-Altman analysis. For each feature, the mean feature value change and the distance spanned by the 95% limits of agreement were normalized to the mean feature value, yielding normalized range of agreement (nRoA) and normalized bias (nBias). Using Wilcoxon signed rank tests, nRoA and nBias were compared with values computed previously in 27 healthy patient scans (mean voxel size: 0.67mm×0.67mm×1mm) acquired at a different institution. Results: nRoA was significantly (p<0.001) larger in cancer patients than healthy patients. Differences in nBias were not significant (p=0.23). The 20 features identified previously as having nRoA<20% for healthy patients had the lowest nRoA values in the current database, with an average increase of 5.6%. Conclusion: Despite differences in CT scanner type, scan resolution, and patient health status, the same 20 features remained stable (i.e., low variability and bias) in the absence of disease changes for databases from two institutions. Identification of

  9. The assessment of the role of baseline low-dose CT scan in patients at high risk of lung cancer

    PubMed Central

    Kołaczyk, Katarzyna; Walecka, Anna; Grodzki, Tomasz; Alchimowicz, Jacek; Smereczyński, Andrzej; Kiedrowicz, Radosław

    2014-01-01

    Summary Background Despite the progress in contemporary medicine comprising diagnostic and therapeutic methods, lung cancer is still one of the biggest health concerns in many countries of the world. The main purpose of the study was to evaluate the detection rate of pulmonary nodules and lung cancer in the initial, helical low-dose CT of the chest as well as the analysis of the relationship between the size and the histopathological character of the detected nodules. Material/Methods We retrospectively evaluated 1999 initial, consecutive results of the CT examinations performed within the framework of early lung cancer detection program initiated in Szczecin. The project enrolled persons of both sexes, aged 55–65 years, with at least 20 pack-years of cigarette smoking or current smokers. The analysis included assessment of the number of positive results and the evaluation of the detected nodules in relationship to their size. All of the nodules were classified into I of VI groups and subsequently compared with histopathological type of the neoplastic and nonneoplastic pulmonary lesions. Results Pulmonary nodules were detected in 921 (46%) subjects. What is more, malignant lesions as well as lung cancer were significantly, more frequently discovered in the group of asymptomatic nodules of the largest dimension exceeding 15 mm. Conclusions The initial, low-dose helical CT of the lungs performed in high risk individuals enables detection of appreciable number of indeterminate pulmonary nodules. In most of the asymptomatic patients with histopathologically proven pulmonary nodules greater than 15 mm, the mentioned lesions are malignant, what warrants further, intensified diagnostics. PMID:25057333

  10. Prediction of therapeutic response in steroid-treated pulmonary sarcoidosis. Evaluation of clinical parameters, bronchoalveolar lavage, gallium-67 lung scanning, and serum angiotensin-converting enzyme levels

    SciTech Connect

    Hollinger, W.M.; Staton, G.W. Jr.; Fajman, W.A.; Gilman, M.J.; Pine, J.R.; Check, I.J.

    1985-07-01

    To find a pretreatment predictor of steroid responsiveness in pulmonary sarcoidosis the authors studied 21 patients before and after steroid treatment by clinical evaluation, pulmonary function tests, bronchoalveolar lavage (BAL), gallium-67 lung scan, and serum angiotensin-converting enzyme (SACE) level. Although clinical score, forced vital capacity (FVC), BAL percent lymphocytes (% lymphs), quantitated gallium-67 lung uptake, and SACE levels all improved with therapy, only the pretreatment BAL % lymphs correlated with the improvement in FVC (r = 0.47, p less than 0.05). Pretreatment BAL % lymphs of greater than or equal to 35% predicted improvement in FVC of 10/11 patients, whereas among 10 patients with BAL % lymphs less than 35%, 5 patients improved and 5 deteriorated. Clinical score, pulmonary function parameters, quantitated gallium-67 lung uptake, and SACE level used alone, in combination with BAL % lymphs or in combination with each other, did not improve this predictive value. The authors conclude that steroid therapy improves a number of clinical and laboratory parameters in sarcoidosis, but only the pretreatment BAL % lymphs are useful in predicting therapeutic responsiveness.

  11. Role of (18)F-FDG PET Scan in Rheumatoid Lung Nodule: Case Report and Review of the Literature.

    PubMed

    Chhakchhuak, Christine L; Khosravi, Mehdi; Lohr, Kristine M

    2013-01-01

    Flourine-18 fluoro-2-deoxy-glucose ((18)F-FDG) positron emission tomography combined with computed tomography (PET/CT) is a useful test for the management of malignant conditions. Inflammatory and infectious processes, however, can cause increased uptake on PET scanning, often causing diagnostic dilemmas. This knowledge is important to the rheumatologist not only because of the inflammatory conditions we treat but also because certain rheumatic diseases impose an increased risk of malignancy either due to the disease itself or as a consequence of medications used to treat the rheumatic diseases. There is an increasing body of evidence investigating the role of PET scans in inflammatory conditions. This paper describes a patient with rheumatoid arthritis who developed pulmonary nodules that showed increased uptake on PET/CT scan and reviews the use of PET scanning in the diagnosis and management of rheumatoid arthritis. PMID:23984160

  12. Role of 18F-FDG PET Scan in Rheumatoid Lung Nodule: Case Report and Review of the Literature

    PubMed Central

    Chhakchhuak, Christine L.; Khosravi, Mehdi; Lohr, Kristine M.

    2013-01-01

    Flourine-18 fluoro-2-deoxy-glucose (18F-FDG) positron emission tomography combined with computed tomography (PET/CT) is a useful test for the management of malignant conditions. Inflammatory and infectious processes, however, can cause increased uptake on PET scanning, often causing diagnostic dilemmas. This knowledge is important to the rheumatologist not only because of the inflammatory conditions we treat but also because certain rheumatic diseases impose an increased risk of malignancy either due to the disease itself or as a consequence of medications used to treat the rheumatic diseases. There is an increasing body of evidence investigating the role of PET scans in inflammatory conditions. This paper describes a patient with rheumatoid arthritis who developed pulmonary nodules that showed increased uptake on PET/CT scan and reviews the use of PET scanning in the diagnosis and management of rheumatoid arthritis. PMID:23984160

  13. Lung Texture in Serial Thoracic Computed Tomography Scans: Correlation of Radiomics-based Features With Radiation Therapy Dose and Radiation Pneumonitis Development

    SciTech Connect

    Cunliffe, Alexandra; Armato, Samuel G.; Castillo, Richard; Pham, Ngoc; Guerrero, Thomas; Al-Hallaq, Hania A.

    2015-04-01

    Purpose: To assess the relationship between radiation dose and change in a set of mathematical intensity- and texture-based features and to determine the ability of texture analysis to identify patients who develop radiation pneumonitis (RP). Methods and Materials: A total of 106 patients who received radiation therapy (RT) for esophageal cancer were retrospectively identified under institutional review board approval. For each patient, diagnostic computed tomography (CT) scans were acquired before (0-168 days) and after (5-120 days) RT, and a treatment planning CT scan with an associated dose map was obtained. 32- × 32-pixel regions of interest (ROIs) were randomly identified in the lungs of each pre-RT scan. ROIs were subsequently mapped to the post-RT scan and the planning scan dose map by using deformable image registration. The changes in 20 feature values (ΔFV) between pre- and post-RT scan ROIs were calculated. Regression modeling and analysis of variance were used to test the relationships between ΔFV, mean ROI dose, and development of grade ≥2 RP. Area under the receiver operating characteristic curve (AUC) was calculated to determine each feature's ability to distinguish between patients with and those without RP. A classifier was constructed to determine whether 2- or 3-feature combinations could improve RP distinction. Results: For all 20 features, a significant ΔFV was observed with increasing radiation dose. Twelve features changed significantly for patients with RP. Individual texture features could discriminate between patients with and those without RP with moderate performance (AUCs from 0.49 to 0.78). Using multiple features in a classifier, AUC increased significantly (0.59-0.84). Conclusions: A relationship between dose and change in a set of image-based features was observed. For 12 features, ΔFV was significantly related to RP development. This study demonstrated the ability of radiomics to provide a quantitative, individualized

  14. Selective Nodal Irradiation on Basis of {sup 18}FDG-PET Scans in Limited-Disease Small-Cell Lung Cancer: A Prospective Study

    SciTech Connect

    Loon, Judith van; De Ruysscher, Dirk; Wanders, Rinus; Boersma, Liesbeth; Simons, Jean; Oellers, Michel; Dingemans, Anne-Marie C.; Hochstenbag, Monique; Bootsma, Gerben; Geraedts, Wiel; Pitz, Cordula; Teule, Jaap; Rhami, Ali; Thimister, Willy; Snoep, Gabriel; Dehing-Oberije, Cary; Lambin, Philippe

    2010-06-01

    Purpose: To evaluate the results of selective nodal irradiation on basis of {sup 18}F-deoxyglucose positron emission tomography (PET) scans in patients with limited-disease small-cell lung cancer (LD-SCLC) on isolated nodal failure. Methods and Materials: A prospective study was performed of 60 patients with LD-SCLC. Radiotherapy was given to a dose of 45 Gy in twice-daily fractions of 1.5 Gy, concurrent with carboplatin and etoposide chemotherapy. Only the primary tumor and the mediastinal lymph nodes involved on the pretreatment PET scan were irradiated. A chest computed tomography (CT) scan was performed 3 months after radiotherapy completion and every 6 months thereafter. Results: A difference was seen in the involved nodal stations between the pretreatment {sup 18}F-deoxyglucose PET scans and computed tomography scans in 30% of patients (95% confidence interval, 20-43%). Of the 60 patients, 39 (65%; 95% confidence interval [CI], 52-76%) developed a recurrence; 2 patients (3%, 95% CI, 1-11%) experienced isolated regional failure. The median actuarial overall survival was 19 months (95% CI, 17-21). The median actuarial progression-free survival was 14 months (95% CI, 12-16). 12% (95% CI, 6-22%) of patients experienced acute Grade 3 (Common Terminology Criteria for Adverse Events, version 3.0) esophagitis. Conclusion: PET-based selective nodal irradiation for LD-SCLC resulted in a low rate of isolated nodal failures (3%), with a low percentage of acute esophagitis. These findings are in contrast to those from our prospective study of CT-based selective nodal irradiation, which resulted in an unexpectedly high percentage of isolated nodal failures (11%). Because of the low rate of isolated nodal failures and toxicity, we believe that our data support the use of PET-based SNI for LD-SCLC.

  15. Lung ischaemia–reperfusion injury in a canine model: dual-energy CT findings with pathophysiological correlation

    PubMed Central

    Xu, K; Zhang, L J; Morelli, J; Krazinski, A W; Silverman, J R; Schoepf, U J; Lu, G M

    2014-01-01

    Objective: To evaluate dual-energy CT (DECT) findings of pulmonary ischaemic–reperfusion injury (PIRI) and its pathophysiological correlation in the canine model. Methods: A PIRI model was established in 11 canines, utilizing closed pectoral balloon occlusion. Two control canines were also included. For the PIRI model, the left pulmonary artery was occluded with a balloon, which was deflated and removed after 2 h. DECT was performed before, during occlusion and at 2, 3 and 4 h thereafter and was utilized to construct pulmonary perfusion maps. Immediately after the CT scan at the fourth hour post reperfusion, the canines were sacrificed, and lung specimens were harvested for pathological analysis. CT findings, pulmonary artery pressure and blood gas results were then analysed. Results: Data at every time point were available for 10 animals (experimental group, n = 8; control group, n = 2). Quantitative measurements from DECT pulmonary perfusion maps found iodine attenuation values of the left lung to be the lowest at 2 h post embolization and the highest at 1 h post reperfusion. In the contralateral lung, perfusion values also peaked at 1 h post reperfusion. Continuous hypoxia and acid–based disorders were observed during PIRI, and comprehensive analysis showed physiological changes to be worst at 3 h post reperfusion. Conclusion: DECT pulmonary perfusion mapping demonstrated pulmonary perfusion of the bilateral lungs to be the greatest at 1 h post reperfusion. These CT findings corresponded with pathophysiological changes. Advances in knowledge: DECT pulmonary perfusion mapping can be used to evaluate lung ischaemia–reperfusion injury. PMID:24611753

  16. Transient reductions in leukocyte/endothelium interaction occur early in hyperoxic lung injury, as seen using scanning electron microscopy (SEM)

    SciTech Connect

    Allen, C.B.; Tucker, A. Colorado State Univ., Ft. Collins )

    1990-02-26

    Exposure of rats to 100% O{sub 2} results in an increased number of neutrophils seen adjacent to pulmonary capillary endothelium. Preliminary studies suggested that serotonin depletion using parachlorophenyalanine (PCPA) accelerated the progression of hyperoxic lung injury. The authors chose to study leukocyte margination in hyperoxic lung injury using SEM to survey pulmonary vessels >20 um diameter in serotonin-intact rats and serotonin-depleted rats exposed to 100% O{sub 2} for 12, 24, 36, 48, 56, and 60 hours. In control rats, the average density of marginated leukocytes was 1,703/mm{sup 2}. At 12, 24 and 36 hours of exposure to 100% O{sub 2}, this density had been reduced to 599/mm{sup 2}, 683/mm{sup 2} and 733/mm{sup 2}, respectively (p{le}0.05). At 48 hours, the leukocyte density, 2,009/mm{sup 2}, was greater than the control value. At 60 hours of exposure, leukocyte densities were not different from control values. Serotonin-depletion did not significantly change this pattern. These findings suggest that hyperoxia causes an earlier change in endothelium/leukocyte interaction than previously thought, and that after early reductions in leukocyte margination, leukocyte densities rebound toward control levels by 48 hours of exposure.

  17. Advances in lung preservation.

    PubMed

    Machuca, Tiago N; Cypel, Marcelo; Keshavjee, Shaf

    2013-12-01

    After a brief review of conventional lung preservation, this article discusses the rationale behind ex vivo lung perfusion and how it has shifted the paradigm of organ preservation from conventional static cold ischemia to the utilization of functional normothermia, restoring the lung's own metabolism and its reparative processes. Technical aspects and previous clinical experience as well as opportunities to address specific donor organ injuries in a personalized medicine approach are also reviewed. PMID:24206857

  18. Use of A-scan for penetration control during dual-frequency ultrasound thermal therapy of superficial tissues overlaying bone and lung

    NASA Astrophysics Data System (ADS)

    Moros, Eduardo G.; Straube, William L.; Fan, Xiaobing

    1999-05-01

    An ultrasonic system capable of Lateral Power Conformability, Penetration Depth Control (PDC), and the ability to deliver hyperthermia concomitantly with external beam radiation is being developed. PDC is achieved by simultaneously insonating with beams of low (1 MHz) and high (5 MHz) frequency. This paper presents a sono-thermal numerical evaluation of the impact of PDC on thermal dose in the treatment of chest wall volumes. The main goal is to assess the potential advantages of impedance-mismatched interface depth-mapping, using therapy transducers in A-scan mode, to select optimal relative output intensities of the beams as a function of bone and lung depths. Simulation results for a representative chest wall anatomy showed that there exists a strong relationship between optimal relative output intensities and bone/lung depth for maximum thermal dose and minimum muscle-bone interface temperature. Consequently, interface depth-mapping prior to a dual- frequency ultrasound hyperthermia treatment would provide patient-specific data useful for selecting PDC parameters that maximize thermal dose and minimize bone heating.

  19. Development and validation of a segmentation-free polyenergetic algorithm for dynamic perfusion computed tomography.

    PubMed

    Lin, Yuan; Samei, Ehsan

    2016-07-01

    Dynamic perfusion imaging can provide the morphologic details of the scanned organs as well as the dynamic information of blood perfusion. However, due to the polyenergetic property of the x-ray spectra, beam hardening effect results in undesirable artifacts and inaccurate CT values. To address this problem, this study proposes a segmentation-free polyenergetic dynamic perfusion imaging algorithm (pDP) to provide superior perfusion imaging. Dynamic perfusion usually is composed of two phases, i.e., a precontrast phase and a postcontrast phase. In the precontrast phase, the attenuation properties of diverse base materials (e.g., in a thorax perfusion exam, base materials can include lung, fat, breast, soft tissue, bone, and metal implants) can be incorporated to reconstruct artifact-free precontrast images. If patient motions are negligible or can be corrected by registration, the precontrast images can then be employed as a priori information to derive linearized iodine projections from the postcontrast images. With the linearized iodine projections, iodine perfusion maps can be reconstructed directly without the influence of various influential factors, such as iodine location, patient size, x-ray spectrum, and background tissue type. A series of simulations were conducted on a dynamic iodine calibration phantom and a dynamic anthropomorphic thorax phantom to validate the proposed algorithm. The simulations with the dynamic iodine calibration phantom showed that the proposed algorithm could effectively eliminate the beam hardening effect and enable quantitative iodine map reconstruction across various influential factors. The error range of the iodine concentration factors ([Formula: see text]) was reduced from [Formula: see text] for filtered back-projection (FBP) to [Formula: see text] for pDP. The quantitative results of the simulations with the dynamic anthropomorphic thorax phantom indicated that the maximum error of iodine concentrations can be reduced from

  20. Three-dimensional reconstruction and display of the heart, lungs and circulation by multiplanar X-ray scanning videodensitometry

    NASA Technical Reports Server (NTRS)

    Robb, R. A.; Ritman, E. L.; Wood, E. H.

    1975-01-01

    A device was developed which makes possible the dynamic reconstruction of the heart and lungs within the intact thorax of a living dog or human and which can record approximately 30 multiplanar X-ray images of the thorax practically instantaneously, and at frequent enough intervals of time and with sufficient density and spatial resolution to capture and resolve the most rapid changes in cardiac structural detail throughout each cardiac cycle. It can be installed in a clinical diagnostic setting as well as in a research environment and its construction and application for determination and display in real-time modes of cross sections of the functioning thorax and its contents of living animals and man is technologically feasible.

  1. Interplay effects in proton scanning for lung: a 4D Monte Carlo study assessing the impact of tumor and beam delivery parameters

    NASA Astrophysics Data System (ADS)

    Dowdell, S.; Grassberger, C.; Sharp, G. C.; Paganetti, H.

    2013-06-01

    Relative motion between a tumor and a scanning proton beam results in a degradation of the dose distribution (interplay effect). This study investigates the relationship between beam scanning parameters and the interplay effect, with the goal of finding parameters that minimize interplay. 4D Monte Carlo simulations of pencil beam scanning proton therapy treatments were performed using the 4DCT geometry of five lung cancer patients of varying tumor size (50.4-167.1 cc) and motion amplitude (2.9-30.1 mm). Treatments were planned assuming delivery in 35 × 2.5 Gy(RBE) fractions. The spot size, time to change the beam energy (τes), time required for magnet settling (τss), initial breathing phase, spot spacing, scanning direction, scanning speed, beam current and patient breathing period were varied for each of the five patients. Simulations were performed for a single fraction and an approximation of conventional fractionation. For the patients considered, the interplay effect could not be predicted using the superior-inferior motion amplitude alone. Larger spot sizes (σ ˜ 9-16 mm) were less susceptible to interplay, giving an equivalent uniform dose (EUD) of 99.0 ± 4.4% (1 standard deviation) in a single fraction compared to 86.1 ± 13.1% for smaller spots (σ ˜ 2-4 mm). The smaller spot sizes gave EUD values as low as 65.3% of the prescription dose in a single fraction. Reducing the spot spacing improved the target dose homogeneity. The initial breathing phase can have a significant effect on the interplay, particularly for shorter delivery times. No clear benefit was evident when scanning either parallel or perpendicular to the predominant axis of motion. Longer breathing periods decreased the EUD. In general, longer delivery times led to lower interplay effects. Conventional fractionation showed significant improvement in terms of interplay, giving a EUD of at least 84.7% and 100.0% of the prescription dose for the small and larger spot sizes respectively

  2. Interplay effects in proton scanning for lung: a 4D Monte Carlo study assessing the impact of tumor and beam delivery parameters.

    PubMed

    Dowdell, S; Grassberger, C; Sharp, G C; Paganetti, H

    2013-06-21

    Relative motion between a tumor and a scanning proton beam results in a degradation of the dose distribution (interplay effect). This study investigates the relationship between beam scanning parameters and the interplay effect, with the goal of finding parameters that minimize interplay. 4D Monte Carlo simulations of pencil beam scanning proton therapy treatments were performed using the 4DCT geometry of five lung cancer patients of varying tumor size (50.4-167.1 cc) and motion amplitude (2.9-30.1 mm). Treatments were planned assuming delivery in 35 × 2.5 Gy(RBE) fractions. The spot size, time to change the beam energy (τes), time required for magnet settling (τss), initial breathing phase, spot spacing, scanning direction, scanning speed, beam current and patient breathing period were varied for each of the five patients. Simulations were performed for a single fraction and an approximation of conventional fractionation. For the patients considered, the interplay effect could not be predicted using the superior-inferior motion amplitude alone. Larger spot sizes (σ ~ 9-16 mm) were less susceptible to interplay, giving an equivalent uniform dose (EUD) of 99.0 ± 4.4% (1 standard deviation) in a single fraction compared to 86.1 ± 13.1% for smaller spots (σ ~ 2-4 mm). The smaller spot sizes gave EUD values as low as 65.3% of the prescription dose in a single fraction. Reducing the spot spacing improved the target dose homogeneity. The initial breathing phase can have a significant effect on the interplay, particularly for shorter delivery times. No clear benefit was evident when scanning either parallel or perpendicular to the predominant axis of motion. Longer breathing periods decreased the EUD. In general, longer delivery times led to lower interplay effects. Conventional fractionation showed significant improvement in terms of interplay, giving a EUD of at least 84.7% and 100.0% of the prescription dose for the small and larger spot sizes respectively. The

  3. The lung in space

    NASA Technical Reports Server (NTRS)

    Prisk, G. Kim

    2005-01-01

    The lung is exquisitely sensitive to gravity, which induces gradients in ventilation, blood flow, and gas exchange. Studies of lungs in microgravity provide a means of elucidating the effects of gravity. They suggest a mechanism by which gravity serves to match ventilation to perfusion, making for a more efficient lung than anticipated. Despite predictions, lungs do not become edematous, and there is no disruption to, gas exchange in microgravity. Sleep disturbances in microgravity are not a result of respiratory-related events; obstructive sleep apnea is caused principally by the gravitational effects on the upper airways. In microgravity, lungs may be at greater risk to the effects of inhaled aerosols.

  4. Xenogeneic lung transplantation models

    PubMed Central

    Burdorf, Lars; Azimzadeh, Agnes M.; Pierson, Richard N.

    2014-01-01

    Summary Study of lung xenografts has proven useful to understand the remaining barriers to successful transplantation of other organ xenografts. In this chapter, the history and current status of lung xenotransplantation will be briefly reviewed and two different experimental models, the ex vivo porcine-to-human lung perfusion and the in vivo xenogeneic lung transplantation, will be presented. We will focus on the technical details of these lung xenograft models in sufficient detail, list the needed materials and mention analysis techniques to allow others to adopt them with minimal learning curve. PMID:22565996

  5. Fasudil and SOD Packaged in Peptide-studded-liposomes: Properties, Pharmacokinetics and Ex-vivo Targeting to Isolated Perfused Rat Lungs

    PubMed Central

    Gupta, Nilesh; Al-Saikhan, Fahad I; Patel, Brijeshkumar; Rashid, Jahidur; Ahsan, Fakhrul

    2015-01-01

    The present study investigated the feasibility of encapsulating two drugs, fasudil and superoxide dismutase (SOD), into liposomes for targeted and inhalational delivery to the pulmonary vasculature to treat pulmonary arterial hypertension (PAH). Nanosized liposomes were prepared by a thin-film formation and extrusion method, and the drugs were encapsulated by a modified freeze-thaw technique. The peptide CARSKNKDC (CAR), a pulmonary-specific targeting sequence, was conjugated on the surface of liposomes. Formulations were optimized for various physicochemical properties, tested for their ex-vivo and in-vivo drug absorption after intratracheal administration, and evaluated for short-term safety in healthy rats. The homogenous nanosized liposomes contained both SOD (~55% entrapment) and fasudil (~40% entrapment), and were stable at 4°C and after nebulization. Liposomes released the drugs in a controlled-release fashion. Compared with plain liposomes, CAR-liposomes increased the uptake by pulmonary endothelial and smooth muscle cells by ~2-fold. CAR-liposomes extended the biological half-lives of SOD and fasudil by ~3-fold. Ex-vivo studies demonstrated that CAR-liposomes were better retained in the lungs than plain liposomes. Bronchoalveolar lavage studies indicated the safety of peptide-equipped liposomes as pulmonary delivery carriers. Overall, this study demonstrates that CAR-liposomes may be used as inhalational carriers for SOD plus fasudil-based combination therapy for PAH. PMID:25888802

  6. Fasudil and SOD packaged in peptide-studded-liposomes: Properties, pharmacokinetics and ex-vivo targeting to isolated perfused rat lungs.

    PubMed

    Gupta, Nilesh; Al-Saikhan, Fahad I; Patel, Brijeshkumar; Rashid, Jahidur; Ahsan, Fakhrul

    2015-07-01

    The present study investigated the feasibility of encapsulating two drugs, fasudil and superoxide dismutase (SOD), into liposomes for targeted and inhalational delivery to the pulmonary vasculature to treat pulmonary arterial hypertension (PAH). Nanosized liposomes were prepared by a thin-film formation and extrusion method, and the drugs were encapsulated by a modified freeze-thaw technique. The peptide CARSKNKDC (CAR), a pulmonary-specific targeting sequence, was conjugated on the surface of liposomes. Formulations were optimized for various physicochemical properties, tested for their ex-vivo and in-vivo drug absorption after intratracheal administration, and evaluated for short-term safety in healthy rats. The homogenous nanosized liposomes contained both SOD (~55% entrapment) and fasudil (~40% entrapment), and were stable at 4°C and after nebulization. Liposomes released the drugs in a controlled-release fashion. Compared with plain liposomes, CAR-liposomes increased the uptake by pulmonary endothelial and smooth muscle cells by ~2-fold. CAR-liposomes extended the biological half-lives of SOD and fasudil by ~3-fold. Ex-vivo studies demonstrated that CAR-liposomes were better retained in the lungs than plain liposomes. Bronchoalveolar lavage studies indicated the safety of peptide-equipped liposomes as pulmonary delivery carriers. Overall, this study demonstrates that CAR-liposomes may be used as inhalational carriers for SOD plus fasudil-based combination therapy for PAH. PMID:25888802

  7. Administration of hydrogen sulfide via extracorporeal membrane lung ventilation in sheep with partial cardiopulmonary bypass perfusion: a proof of concept study on metabolic and vasomotor effects

    PubMed Central

    2011-01-01

    Introduction Although inhalation of 80 parts per million (ppm) of hydrogen sulfide (H2S) reduces metabolism in mice, doses higher than 200 ppm of H2S were required to depress metabolism in rats. We therefore hypothesized that higher concentrations of H2S are required to reduce metabolism in larger mammals and humans. To avoid the potential pulmonary toxicity of H2S inhalation at high concentrations, we investigated whether administering H2S via ventilation of an extracorporeal membrane lung (ECML) would provide means to manipulate the metabolic rate in sheep. Methods A partial venoarterial cardiopulmonary bypass was established in anesthetized, ventilated (fraction of inspired oxygen = 0.5) sheep. The ECML was alternately ventilated with air or air containing 100, 200, or 300 ppm H2S for intervals of 1 hour. Metabolic rate was estimated on the basis of total CO2 production (V˙CO2) and O2 consumption (V˙O2). Continuous hemodynamic monitoring was performed via indwelling femoral and pulmonary artery catheters. Results V˙CO2, V˙O2, and cardiac output ranged within normal physiological limits when the ECML was ventilated with air and did not change after administration of up to 300 ppm H2S. Administration of 100, 200 and 300 ppm H2S increased pulmonary vascular resistance by 46, 52 and 141 dyn·s/cm5, respectively (all P ≤ 0.05 for air vs. 100, 200 and 300 ppm H2S, respectively), and mean pulmonary artery pressure by 4 mmHg (P ≤ 0.05), 3 mmHg (n.s.) and 11 mmHg (P ≤ 0.05), respectively, without changing pulmonary capillary wedge pressure or cardiac output. Exposure to 300 ppm H2S decreased systemic vascular resistance from 1,561 ± 553 to 870 ± 138 dyn·s/cm5 (P ≤ 0.05) and mean arterial pressure from 121 ± 15 mmHg to 66 ± 11 mmHg (P ≤ 0.05). In addition, exposure to 300 ppm H2S impaired arterial oxygenation (PaO2 114 ± 36 mmHg with air vs. 83 ± 23 mmHg with H2S; P ≤ 0.05). Conclusions Administration of up to 300 ppm H2S via ventilation of an

  8. Determination of Internal Target Volume From a Single Positron Emission Tomography/Computed Tomography Scan in Lung Cancer

    SciTech Connect

    Chang Guoping; Chang Tingting; Pan Tinsu; Clark, John W.; Mawlawi, Osama R.

    2012-05-01

    Purpose: The use of four-dimensional computed tomography (4D-CT) to determine the tumor internal target volume (ITV) is usually characterized by high patient radiation exposure. The objective of this study was to propose and evaluate an approach that relies on a single static positron emission tomography (PET)/CT scan to determine the ITV, thereby eliminating the need for 4D-CT and thus reduce patient radiation dose. Methods and Materials: The proposed approach is based on the concept that the observed PET image is the result of a joint convolution of an ideal PET image (free from motion and partial volume effect) with a motion-blurring kernel (MBK) and partial volume effect. In this regard, the MBK and tumor ITV are then estimated from the deconvolution of this joint model. To test this technique, phantom and patient studies were performed using different sphere/tumor sizes and motion trajectories. In all studies, a 4D-CT and a PET/CT image of the sphere/tumor were acquired. The ITV from the proposed technique was then compared to the maximum intensity projection (MIP) volume of the 4D-CT images. A Dice coefficient of the two volumes was calculated to represent the similarity between the two ITVs. Results: The average ITVs of the proposed technique were 97.2% {+-} 0.3% and 81.0% {+-} 16.7% similar to the MIP volume in the phantom and patient studies, respectively. The average dice coefficients were 0.87 {+-} 0.05 and 0.73 {+-} 0.16, respectively, for the two studies. Conclusion: Using the proposed approach, a single static PET/CT scan has the potential to replace a 4D-CT to determine the tumor ITV. This approach has the added advantage of reducing patient radiation exposure and determining the tumor MBK compared to 4D-CT/MIP-CT.

  9. Early radionuclide scans for risk assessment in suspected acute myocardial infarction.

    PubMed Central

    Norris, S. L.; Haywood, L. J.; Sobel, E.; Hung, G. L.; deGuzman, M.; Siegel, M.

    1997-01-01

    First-day thallium-201 myocardial perfusion scans and technetium-99m RBC gated scintiangiography were performed during the initial clinical and prognostic evaluation of 69 patients with suspected acute myocardial infarction. Patients were monitored for clinical course, diagnosis confirmation, and use of specialty services (cardiac catheterization, percutaneous balloon angioplasty, and cardiac surgery) during hospitalization. Myocardial infarction, confirmed in 20 patients, was associated with significantly more left ventricular dilatation, lower ejection fractions, lower peak left ventricular filling rates, wall motion abnormalities, and thallium-201 perfusion defects than nonmyocardial infarction patients. Among all patients, left ventricular dilatation carried a relative risk of myocardial infarction of 5.8; low ejection fraction and right ventricular dilatation were strongly associated with myocardial infarction. A logistic model for congestive heart failure included: left ventricular dilation, lower mean left ventricular filling rates and time to peak filling rates, and abnormal thallium-201 lung:heart uptakes. Among nonmyocardial infarction patients, subsequent cardiac catheterization was predicted by the presence of anterior thallium-201 perfusion defects, Killip functional class II-III, and ischemia on ECG. These findings suggest that early detection of myocardial perfusion defects and cardiac dysfunction by radionuclide scans enhances initial evaluation of suspected acute myocardial infarction patients. Additional studies are needed to confirm these findings. PMID:9433058

  10. Hepatic Perfusion Therapy.

    PubMed

    Rajeev, Rahul; Gamblin, T Clark; Turaga, Kiran K

    2016-04-01

    Isolated hepatic perfusion uses the unique vascular supply of hepatic malignancies to deliver cytotoxic chemotherapy. The procedure involves vascular isolation of the liver and delivery of chemotherapy via the hepatic artery and extraction from retrohepatic vena cava. Benefits of hepatic perfusion have been observed in hepatic metastases of ocular melanoma and colorectal cancer and primary hepatocellular carcinoma. Percutaneous and prophylactic perfusions are avenues of ongoing research.

  11. Effect of shed blood retransfusion on pulmonary perfusion after total knee arthroplasty: a prospective controlled study

    PubMed Central

    Kaya, Eser; Kose, Kamil Cagri; Fidan, Fatma; Ergan, Volkan; Fidan, Hüseyin

    2006-01-01

    Postoperative shed blood retransfusion (autotransfusion) is a commonly used salvage method following major surgical operations, such as total knee arthroplasty (TKA). The systemic effects of shed blood are still unclear. We studied the effect of residual substances in the retransfused shed blood, on lung perfusion after TKA. Fifteen unilateral and one bilateral TKAs were performed with autotransfusion (the study group) and 15 unilateral and three bilateral TKAs were performed in a control group. Lung X-rays, arterial blood gases (ABG), D-dimer values, and lung perfusion scintigraphies were performed preoperatively and postoperatively. A mean of 300.0 ± 335.6 ml of bank blood was needed in the autotransfusion group and a mean of 685.7 ± 365.5 ml of bank blood was needed in the control group (p=0.001). There was a postoperative segmental perfusion defect at the lateral segment of the superior lobe of the left lung in one patient of the control group and he also had risk factors for thrombosis. Although both groups had a decrease in lung perfusion postoperatively, there were no significant differences among the groups regarding the lung perfusion scintigraphy, chest X-rays, ABG, and D-dimer values. In conclusion, although pulmonary perfusion diminishes following TKA, shed blood retransfusion does not add any risk to pulmonary perfusion. PMID:17115155

  12. Hepatic perfusion abnormalities during CT angiography: Detection and interpretation

    SciTech Connect

    Freeny, P.C.; Marks, W.M.

    1986-06-01

    Twenty-seven perfusion abnormalities were detected in 17 of 50 patients who underwent computed tomographic angiography (CTA) of the liver. All but one of the perfusion abnormalities occurred in patients with primary or metastatic liver tumors. Perfusion abnormalities were lobar in nine cases, segmental in 11, and subsegmental in seven; 14 were hypoperfusion and 13 were hyperperfusion abnormalities. The causes for the abnormalities included nonperfusion of a replaced hepatic artery (n = 11), cirrhosis and nodular regeneration (n = 3), altered hepatic hemodynamics (e.g., siphoning, laminar flow) caused by tumor (n = 7), contrast media washout from a nonperfused vessel (n = 1), compression of adjacent hepatic parenchyma (n = 1), and unknown (n = 4). Differentiation of perfusion abnormalities from tumor usually can be made by comparing the morphology of the known tumor with the suspected perfusion abnormality, changes of each on delayed CTA scans, and review of initial angiograms and other imaging studies.

  13. High lung volume increases stress failure in pulmonary capillaries

    NASA Technical Reports Server (NTRS)

    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

  14. Comparison between target margins derived from 4DCT scans and real-time tumor motion tracking: Insights from lung tumor patients treated with robotic radiosurgery

    SciTech Connect

    Descovich, Martina McGuinness, Christopher; Kannarunimit, Danita; Chen, Josephine; Pinnaduwage, Dilini; Pouliot, Jean; Kased, Norbert; Gottschalk, Alexander R.; Yom, Sue S.

    2015-03-15

    Purpose: A unique capability of the CyberKnife system is dynamic target tracking. However, not all patients are eligible for this approach. Rather, their tumors are tracked statically using the vertebral column for alignment. When using static tracking, the internal target volume (ITV) is delineated on the four-dimensional (4D) CT scan and an additional margin is added to account for setup uncertainty [planning target volume (PTV)]. Treatment margins are difficult to estimate due to unpredictable variations in tumor motion and respiratory pattern during the course of treatment. The inability to track the target and detect changes in respiratory characteristics might result in geographic misses and local tumor recurrences. The purpose of this study is to develop a method to evaluate the adequacy of ITV-to-PTV margins for patients treated in this manner. Methods: Data from 24 patients with lesions in the upper lobe (n = 12), middle lobe (n = 3), and lower lobe (n = 9) were included in this study. Each patient was treated with dynamic tracking and underwent 4DCT scanning at the time of simulation. Data including the 3D coordinates of the target over the course of treatment were extracted from the treatment log files and used to determine actual target motion in the superior–inferior (S–I), anterior–posterior (A–P), and left–right (L–R) directions. Different approaches were used to calculate anisotropic and isotropic margins, assuming that the tumor moves as a rigid body. Anisotropic margins were calculated by separating target motion in the three anatomical directions, and a uniform margin was calculated by shifting the gross tumor volume contours in the 3D space and by computing the percentage of overlap with the PTV. The analysis was validated by means of a theoretical formulation. Results: The three methods provided consistent results. A uniform margin of 4.5 mm around the ITV was necessary to assure 95% target coverage for 95% of the fractions included

  15. Topographic distribution of pulmonary ventilation and perfusion in the horse

    SciTech Connect

    Amis, T.C.; Pascoe, J.R.; Hornof, W.

    1984-08-01

    The regional distribution of ventilation to perfusion ratios (VA/Q) in the lungs of 8 healthy standing Thoroughbred geldings (4.4 +/- 1.5 years, 465.7 +/- 46.6 kg) was studied, using steady-state inhalation and IV infusion of the radioactive gas krypton-81m. The VA/Q was uniformly distributed within a vertical lung strip centered over the 9th rib on the right side. Ventilation per unit of alveolar volume (V/VA) assessed from the clearance of inhaled radioactive gas in 5 horses increased from 0.49 +/- 0.13 (arbitrary units) in nondependent lung zones to 1.45 +/- 0.16 in dependent lung zones. Seemingly, a vertical gradient of pulmonary ventilation exists in the horse that is matched by a similar gradient of perfusion.

  16. Respiratory Motion Changes of Lung Tumors Over the Course of Radiation Therapy Based on Respiration-Correlated Four-Dimensional Computed Tomography Scans

    SciTech Connect

    Redmond, Kristin J.; Song, Danny Y.; Fox, Jana L.; Zhou, Jessica; Rosenzweig, C. Nicole; Ford, Eric

    2009-12-01

    Purpose: To determine whether lung tumor respiratory excursion at simulation is predictive of excursion during radiation and whether phase offsets between tumor and surrogate markers are constant throughout treatment. Methods and Materials: Respiration-correlated CT scans and two rescans (using a Brilliance Big Bore spiral CT simulator; Philips, Inc.) were obtained from 20 patients at simulation. Gross tumor volume (GTV) was contoured on 10 phases of the respiratory cycle, and excursions were calculated. Diaphragm and xyphoid motion were quantified. Phase offsets, DELTAPHI, were calculated for patients with a GTV motion of >3 mm. Interfraction differences in excursions between simulation and rescans and magnitudes of variation in phase offset between fractions were evaluated. Results: Mean GTV excursions at simulation in superior-inferior, anterior-posterior, and medial-lateral directions were 0.67, 0.29, and 0.21 cm, respectively. The magnitude of superior-inferior GTV excursion correlated with tumor location (upper vs. lower lobe, p = 0.011). GTV excursions between simulation and rescan 1 (p = 0.115) and between simulation and rescan 2 (p = 0.071) were stable. Fourteen patients were analyzed for variations in phase offsets. GTV-xyphoid phase offset changed significantly between simulation and rescan 1 (p = 0.007) and simulation and rescan 2 (p = 0.008), with mean DELTAPHI values of 13.2% (rescan 1) and 14.3% (rescan 2). Xyphoid-diaphragm offset changed between simulation and rescan 1 (p = 0.004) and between simulation and rescan 2 (p = 0.012), with mean DELTAPHI values of 14.5% (rescan 1) and 7.6% (rescan 2). Conclusions: Interfraction consistency in tumor excursion suggests tumor excursion at simulation may direct therapy. Significant variations in phase lag between GTV and other anatomic structures throughout treatment have important implications for techniques that rely on surrogate structures to predict tumor motion

  17. Low power laser protects human erythrocytes In an In vitro model of artificial heart-lung machines.

    PubMed

    Itoh, T; Murakami, H; Orihashi, K; Sueda, T; Kusumoto, Y; Kakehashi, M; Matsuura, Y

    2000-11-01

    The protective effect of the low power helium-neon (He-Ne) laser against the damage of human erythrocytes in whole blood was examined in a perfusion model using an artificial heart-lung machine. Preserved human whole blood was diluted and perfused in 2 closed circuits with a double roller pump. The laser irradiated one of the circuits (laser group), and none the other (control group). In the laser group, erythrocyte deformability and erythrocyte adenosine triphosphate (ATP) levels were significantly higher, and free hemoglobin levels were significantly lower than those in the control group. Subsequent morphological findings by means of scanning electron microscope were consistent with these results. Low power He-Ne laser protected human erythrocytes in the preserved diluted whole blood from the damage caused by experimental artificial heart-lung machines. The clinical application of low power laser treatment for extracorporeal circulation is suggested.

  18. Live Imaging of the Lung

    PubMed Central

    Looney, Mark R.; Bhattacharya, Jahar

    2015-01-01

    Live lung imaging has spanned the discovery of capillaries in the frog lung by Malpighi to the current use of single and multiphoton imaging of intravital and isolated perfused lung preparations incorporating fluorescent molecular probes and transgenic reporter mice. Along the way, much has been learned about the unique microcirculation of the lung, including immune cell migration and the mechanisms by which cells at the alveolar-capillary interface communicate with each other. In this review, we highlight live lung imaging techniques as applied to the role of mitochondria in lung immunity, mechanisms of signal transduction in lung compartments, studies on the composition of alveolar wall liquid, and neutrophil and platelet trafficking in the lung under homeostatic and inflammatory conditions. New applications of live lung imaging and the limitations of current techniques are discussed. PMID:24245941

  19. Fast nonlinear regression method for CT brain perfusion analysis.

    PubMed

    Bennink, Edwin; Oosterbroek, Jaap; Kudo, Kohsuke; Viergever, Max A; Velthuis, Birgitta K; de Jong, Hugo W A M

    2016-04-01

    Although computed tomography (CT) perfusion (CTP) imaging enables rapid diagnosis and prognosis of ischemic stroke, current CTP analysis methods have several shortcomings. We propose a fast nonlinear regression method with a box-shaped model (boxNLR) that has important advantages over the current state-of-the-art method, block-circulant singular value decomposition (bSVD). These advantages include improved robustness to attenuation curve truncation, extensibility, and unified estimation of perfusion parameters. The method is compared with bSVD and with a commercial SVD-based method. The three methods were quantitatively evaluated by means of a digital perfusion phantom, described by Kudo et al. and qualitatively with the aid of 50 clinical CTP scans. All three methods yielded high Pearson correlation coefficients ([Formula: see text]) with the ground truth in the phantom. The boxNLR perfusion maps of the clinical scans showed higher correlation with bSVD than the perfusion maps from the commercial method. Furthermore, it was shown that boxNLR estimates are robust to noise, truncation, and tracer delay. The proposed method provides a fast and reliable way of estimating perfusion parameters from CTP scans. This suggests it could be a viable alternative to current commercial and academic methods. PMID:27413770

  20. Advances in physiologic lung assessment via electron beam computed tomography (EBCT)

    NASA Astrophysics Data System (ADS)

    Hoffman, Eric A.

    1999-09-01

    Lung function has been evaluated in both health and disease states by techniques, such as pulmonary function tests, which generally study aggregate function. These decades old modalities have yielded a valuable understanding of global physiologic and pathophysiologic structure-to-function relationships. However, such approaches have reached their limits. They cannot meet the current and anticipated needs of new surgical and pharmaceutical treatments. 4-D CT can provide insights into regional lung function (ventilation and blood flow) and thus can provide information at an early stage of disease when intervention will have the greatest impact. Lung CT over the last decade has helped with further defining anatomic features in disease, but has lagged behind advances on the cellular and molecular front largely because of the failure to account for functional correlates to structural pathology. Commercially available CT scanners are now capable of volumetric data acquisition in a breath-hold and capable of multi-level slice acquisitions of the heart and lungs with a per slice scan aperture of 50 - 300 msec, allowing for regional blood flow measurements. Static, volumetric imaging of the lung is inadequate in that much of lung pathology is a dynamic phenomenon and, thus, is only detectable if the lung is imaged as air and blood are flowing. This paper review the methodologies and early physiologic findings associated with our measures of lung tissue properties coupled with regional ventilation and perfusion.

  1. Nifedipine and thallium-201 myocardial perfusion in progressive systemic sclerosis

    SciTech Connect

    Kahan, A.; Devaux, J.Y.; Amor, B.; Menkes, C.J.; Weber, S.; Nitenberg, A.; Venot, A.; Guerin, F.; Degeorges, M.; Roucayrol, J.C.

    1986-05-29

    Heart disease in patients with progressive systemic sclerosis may be due in part to myocardial ischemia caused by a disturbance of the coronary microcirculation. To determine whether abnormalities of myocardial perfusion in this disorder are potentially reversible, we evaluated the effect of the coronary vasodilator nifedipine on myocardial perfusion assessed by thallium-201 scanning in 20 patients. Thallium-201 single-photon-emission computerized tomography was performed under control conditions and 90 minutes after 20 mg of oral nifedipine. The mean (+/- SD) number of left ventricular segments with perfusion defects decreased from 5.3 +/- 2.0 to 3.3 +/- 2.2 after nifedipine (P = 0.0003). Perfusion abnormalities were quantified by a perfusion score (0 to 2.0) assigned to each left ventricular segment and by a global perfusion score (0 to 18) for the entire left ventricle. The mean perfusion score in segments with resting defects increased from 0.97 +/- 0.24 to 1.26 +/- 0.44 after nifedipine (P less than 0.00001). The mean global perfusion score increased from 11.2 +/- 1.7 to 12.8 +/- 2.4 after nifedipine (P = 0.003). The global perfusion score increased by at least 2.0 in 10 patients and decreased by at least 2.0 in only 1. These observations reveal short-term improvement in thallium-201 myocardial perfusion with nifedipine in patients with progressive systemic sclerosis. The results are consistent with a potentially reversible abnormality of coronary vasomotion in this disorder, but the long-term therapeutic effects of nifedipine remain to be determined.

  2. Donor management and lung preservation for lung transplantation.

    PubMed

    Munshi, Laveena; Keshavjee, Shaf; Cypel, Marcelo

    2013-06-01

    Although lung transplantation has become a life-saving option for patients with end-stage lung disease, this intervention is hampered by a shortage of lungs in view of the growing number of people on the waiting list. Lungs are retrieved from only a small percentage of multiorgan donors, and the transplantation and intensive-care communities have recognised the need to develop innovative methods to expand the donor pool. Advancements in lung-preservation techniques in the preretrieval and postretrieval periods have increased the pool of available donors, and novel research and discoveries in this area have steadily improved post-transplantation adverse events. This Review summarises current best practice and the latest research on intensive-care management of a potential lung donor. We also discuss lung-preservation techniques, including advancements in normothermic ex-vivo lung perfusion, and the potential for a personalised medicine approach to the organ. PMID:24429157

  3. Dynamic chest image analysis: model-based pulmonary perfusion analysis with pyramid images

    NASA Astrophysics Data System (ADS)

    Liang, Jianming; Haapanen, Arto; Jaervi, Timo; Kiuru, Aaro J.; Kormano, Martti; Svedstrom, Erkki; Virkki, Raimo

    1998-07-01

    The aim of the study 'Dynamic Chest Image Analysis' is to develop computer analysis and visualization methods for showing focal and general abnormalities of lung ventilation and perfusion based on a sequence of digital chest fluoroscopy frames collected at different phases of the respiratory/cardiac cycles in a short period of time. We have proposed a framework for ventilation study with an explicit ventilation model based on pyramid images. In this paper, we extend the framework to pulmonary perfusion study. A perfusion model and the truncated pyramid are introduced. The perfusion model aims at extracting accurate, geographic perfusion parameters, and the truncated pyramid helps in understanding perfusion at multiple resolutions and speeding up the convergence process in optimization. Three cases are included to illustrate the experimental results.

  4. National Lung Screening Trial (NLST)

    Cancer.gov

    The National Lung Screening Trial (NLST), a research study sponsored by the National Cancer Institute that used low-dose helical CT scans or chest X-ray to screen men and women at risk for lung cancer.

  5. CT perfusion: principles, applications, and problems

    NASA Astrophysics Data System (ADS)

    Lee, Ting-Yim

    2004-10-01

    The fast scanning speed of current slip-ring CT scanners has enabled the development of perfusion imaging techniques with intravenous injection of contrast medium. In a typical CT perfusion study, contrast medium is injected and rapid scanning at a frequency of 1-2 Hz is used to monitor the first circulation of the injected contrast medium through a 1-2 cm thick slab of tissue. From the acquired time-series of CT images, arteries can be identified within the tissue slab to derive the arterial contrast concentration curve, Ca(t) while each individual voxel produces a tissue residue curve, Q(t) for the corresponding tissue region. Deconvolution between the measured Ca(t) and Q(t) leads to the determination of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in brain studies. In this presentation, an important application of CT perfusion in acute stroke studies - the identification of the ischemic penumbra via the CBF/CBV mismatch and factors affecting the quantitative accuracy of deconvolution, including partial volume averaging, arterial delay and dispersion are discussed.

  6. Pulmonary Perfusion MRI using Interleaved Variable Density Sampling and HighlY Constrained Cartesian Reconstruction (HYCR)

    PubMed Central

    Wang, Kang; Schiebler, Mark L.; Francois, Christopher J.; Del Rio, A. Munoz; Cornejo, Ma. Daniela; Bell, Laura C.; Korosec, Frank R.; Brittain, Jean H.; Holmes, James H.; Nagle, Scott K.

    2012-01-01

    Purpose To demonstrate the feasibility of performing single breath-hold, non-cardiac gated, ultrafast, high spatial-temporal resolution whole chest MR pulmonary perfusion imaging in humans. Materials and Methods Eight (8) subjects (5 male, 3 female) were scanned with the proposed method on a 3T clinical scanner using a 32-channel phased-array coil. Seven (88%) were healthy volunteers, and one was a patient volunteer with sarcoidosis. The peak lung enhancement phase for each subject was scored for gravitational effect, peak parenchymal enhancement and severity of artifacts by 3 cardiothoracic radiologists independently. Results All studies were successfully performed by MR technologists without any additional training. Mean parenchymal signal was very good, measuring 0.78 ± 0.13 (continuous scale, 0 = “none” → 1 = “excellent”). Mean level of motion artifacts was low, measuring 0.13 ± 0.08 (continuous scale, 0 = “none” → 1 = “severe”). Conclusion It is feasible to perform single breath-hold, non-cardiac gated, ultrafast, high spatial-temporal resolution whole chest MR pulmonary perfusion imaging in humans. PMID:23349079

  7. Update on Nonsurgical Lung Volume Reduction Procedures.

    PubMed

    Neder, J Alberto; O'Donnell, Denis E

    2016-01-01

    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) < 25%, residual volume > 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. PMID:27445557

  8. Update on Nonsurgical Lung Volume Reduction Procedures

    PubMed Central

    Neder, J. Alberto; O'Donnell, Denis E.

    2016-01-01

    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) < 25%, residual volume > 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. PMID:27445557

  9. Inhomogeneity of pulmonary perfusion during sustained microgravity

    NASA Technical Reports Server (NTRS)

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

    1994-01-01

    The effects of gravity on the inhomogeneity of pulmonary perfusion in man were studied by performing hyperventilation-breathhold single-breath measurements before, during and after 9 days of continuous exposure to microgravity. In microgravity the indicators of inhomogeneity of perfusion, especially the size of cardiogenic oscillations in expired CO2 and the height of phase 4, were both markedly reduced. Cardiogenic oscillations were reduced to approximately 60 of their preflight standing size, while the height of phase 4 was between 0 and -8% (a terminal fall became a small terminal rise) of preflights standing. The terminal change in CO2 was nearly abolished in microgravity indicating more uniformity of blood flow between lung units that close at the end of expiration and units that remain open. This may result from the disappearance of gravity-dependent topographical inequality of blood flow. The residual cardiographic oscillations in expired CO2 imply a persisting inhomogeneity of perfusion in the absence of gravity at a level larger than acinar.

  10. REDUCTION IN INSPIRATORY FLOW ATTENUATES IL-8 RELEASE AND MAPK ACTIVATION OF LUNG OVERSTRETCH

    EPA Science Inventory

    Lung overstretch involves mechanical factors, including large tidal volumes (VT), which induce inflammatory responses. The current authors hypothesised that inspiratory flow contributes to ventilator-induced inflammation. Buffer-perfused rabbit lungs were ventilated for 2 h with ...

  11. Comparison of 4-Dimensional Computed Tomography Ventilation With Nuclear Medicine Ventilation-Perfusion Imaging: A Clinical Validation Study

    SciTech Connect

    Vinogradskiy, Yevgeniy; Koo, Phillip J.; Castillo, Richard; Castillo, Edward; Guerrero, Thomas; Gaspar, Laurie E.; Miften, Moyed; Kavanagh, Brian D.

    2014-05-01

    Purpose: Four-dimensional computed tomography (4DCT) ventilation imaging provides lung function information for lung cancer patients undergoing radiation therapy. Before 4DCT-ventilation can be implemented clinically it needs to be validated against an established imaging modality. The purpose of this work was to compare 4DCT-ventilation to nuclear medicine ventilation, using clinically relevant global metrics and radiologist observations. Methods and Materials: Fifteen lung cancer patients with 16 sets of 4DCT and nuclear medicine ventilation-perfusion (VQ) images were used for the study. The VQ-ventilation images were acquired in planar mode using Tc-99m-labeled diethylenetriamine-pentaacetic acid aerosol inhalation. 4DCT data, spatial registration, and a density-change-based model were used to compute a 4DCT-based ventilation map for each patient. The percent ventilation was calculated in each lung and each lung third for both the 4DCT and VQ-ventilation scans. A nuclear medicine radiologist assessed the VQ and 4DCT scans for the presence of ventilation defects. The VQ and 4DCT-based images were compared using regional percent ventilation and radiologist clinical observations. Results: Individual patient examples demonstrate good qualitative agreement between the 4DCT and VQ-ventilation scans. The correlation coefficients were 0.68 and 0.45, using the percent ventilation in each individual lung and lung third, respectively. Using radiologist-noted presence of ventilation defects and receiver operating characteristic analysis, the sensitivity, specificity, and accuracy of the 4DCT-ventilation were 90%, 64%, and 81%, respectively. Conclusions: The current work compared 4DCT with VQ-based ventilation using clinically relevant global metrics and radiologist observations. We found good agreement between the radiologist's assessment of the 4DCT and VQ-ventilation images as well as the percent ventilation in each lung. The agreement lessened when the data were analyzed

  12. Imaging findings and cerebral perfusion in arterial ischemic stroke due to transient cerebral arteriopathy in children.

    PubMed

    Barbosa Junior, Alcino Alves; Ellovitch, Saada Resende de Souza; Pincerato, Rita de Cassia Maciel

    2012-01-01

    We report the case of a 4-year-old female child who developed an arterial ischemic stroke in the left middle cerebral artery territory, due to a proximal stenosis of the supraclinoid internal carotid artery, most probably related to transient cerebral arteriopathy of childhood. Computed tomography scan, magnetic resonance imaging, perfusion magnetic resonance and magnetic resonance angiography are presented, as well as follow-up by magnetic resonance and magnetic resonance angiography exams. Changes in cerebral perfusion and diffusion-perfusion mismatch call attention. As far as we know, this is the first report of magnetic resonance perfusion findings in transient cerebral arteriopathy.

  13. Development of an Ex Vivo, Beating Heart Model for CT Myocardial Perfusion

    PubMed Central

    Pelgrim, Gert Jan; Das, Marco; Haberland, Ulrike; Slump, Cees; Handayani, Astri; van Tuijl, Sjoerd; Stijnen, Marco; Klotz, Ernst; Oudkerk, Matthijs; Wildberger, Joachim E.; Vliegenthart, Rozemarijn

    2015-01-01

    Objective. To test the feasibility of a CT-compatible, ex vivo, perfused porcine heart model for myocardial perfusion CT imaging. Methods. One porcine heart was perfused according to Langendorff. Dynamic perfusion scanning was performed with a second-generation dual source CT scanner. Circulatory parameters like blood flow, aortic pressure, and heart rate were monitored throughout the experiment. Stenosis was induced in the circumflex artery, controlled by a fractional flow reserve (FFR) pressure wire. CT-derived myocardial perfusion parameters were analysed at FFR of 1 to 0.10/0.0. Results. CT images did not show major artefacts due to interference of the model setup. The pacemaker-induced heart rhythm was generally stable at 70 beats per minute. During most of the experiment, blood flow was 0.9–1.0 L/min, and arterial pressure varied between 80 and 95 mm/Hg. Blood flow decreased and arterial pressure increased by approximately 10% after inducing a stenosis with FFR ≤ 0.50. Dynamic perfusion scanning was possible across the range of stenosis grades. Perfusion parameters of circumflex-perfused myocardial segments were affected at increasing stenosis grades. Conclusion. An adapted Langendorff porcine heart model is feasible in a CT environment. This model provides control over physiological parameters and may allow in-depth validation of quantitative CT perfusion techniques. PMID:26185756

  14. Laser Doppler Perfusion Imaging with a high-speed CMOS-camera

    NASA Astrophysics Data System (ADS)

    Draijer, Matthijs J.; Hondebrink, Erwin; Steenbergen, Wiendelt; van Leeuwen, Ton G.

    2007-07-01

    The technique of Laser Doppler Perfusion Imaging (LDPI) is widely used for determining cerebral blood flow or skin perfusion in the case of burns. The commonly used Laser Doppler Perfusion Imagers are scanning systems which point by point scan the area under investigation and use a single photo detector to capture the photoelectric current to obtain a perfusion map. In that case the imaging time for a perfusion map of 64 x 64 pixels is around 5 minutes. Disadvantages of a long imaging time for in-vivo imaging are the bigger chance of movement artifacts, reduced comfort for the patient and the inability to follow fast changing perfusion conditions. We present a Laser Doppler Perfusion Imager which makes use of a high speed CMOS-camera. By illuminating the area under investigation and simultaneously taking images at high speed with the camera, it is possible to obtain a perfusion map of the area under investigation in a shorter period of time than with the commonly used Laser Doppler Perfusion Imagers.

  15. High-frequency Electrocardiogram Analysis in the Ability to Predict Reversible Perfusion Defects during Adenosine Myocardial Perfusion Imaging

    NASA Technical Reports Server (NTRS)

    Tragardh, Elin; Schlegel, Todd T.; Carlsson, Marcus; Pettersson, Jonas; Nilsson, Klas; Pahlm, Olle

    2007-01-01

    Background: A previous study has shown that analysis of high-frequency QRS components (HF-QRS) is highly sensitive and reasonably specific for detecting reversible perfusion defects on myocardial perfusion imaging (MPI) scans during adenosine. The purpose of the present study was to try to reproduce those findings. Methods: 12-lead high-resolution electrocardiogram recordings were obtained from 100 patients before (baseline) and during adenosine Tc-99m-tetrofosmin MPI tests. HF-QRS were analyzed regarding morphology and changes in root mean square (RMS) voltages from before the adenosine infusion to peak infusion. Results: The best area under the curve (AUC) was found in supine patients (AUC=0.736) in a combination of morphology and RMS changes. None of the measurements, however, were statistically better than tossing a coin (AUC=0.5). Conclusion: Analysis of HF-QRS was not significantly better than tossing a coin for determining reversible perfusion defects on MPI scans.

  16. Clinical Application and Research Advances of CT Myocardial Perfusion Imaging.

    PubMed

    2016-06-10

    Computed tomography (CT)-based myocardial perfusion imaging (CTP)has been widely recognized as a one-station solution for the imaging of myocardial ischemia-related diseases. This article reviews the clinical scanning protocols,analytical methods,and research advances of CTP in recent years and briefly discusses its limitations and future development. PMID:27469926

  17. Fluorescence spectroscopy and cryoimaging of rat lung tissue mitochondrial redox state

    NASA Astrophysics Data System (ADS)

    Sepehr, R.; Audi, S.; Staniszewski, K.; Maleki, S.; Ranji, M.

    2011-07-01

    The objective of this study was to demonstrate the utility of optical cryoimaging and fluorometry to evaluate tissue redox state of the mitochondrial metabolic coenzymes NADH (Nicotinamide Adenine Dinucleotide) and FAD (Flavin Adenine Dinucleotide) in intact rat lungs. The ratio (NADH/FAD), referred to as mitochondrial redox ratio (RR), is a measure of the lung tissue mitochondrial redox state. Isolated rat lungs were connected to a ventilation-perfused system. Surface NADH and FAD fluorescence signals were acquired before and after lung perfusion in the absence (control perfusate) or presence of potassium cyanide (KCN, complex IV inhibitor) to reduce the mitochondrial respiratory chain (state 5 respiration). Another group of lungs were perfused with control perfusate or KCN-containing perfusate as above, after which the lungs were deflated and frozen rapidly for subsequent 3D cryoimaging. Results demonstrate that lung treatment with KCN increased lung surface NADH signal by 22%, decreased FAD signal by 8%, and as result increased RR by 31% as compared to control perfusate (baseline) values. Cryoimaging results also show that KCN increased mean lung tissue NADH signal by 37%, decreased mean FAD signal by 4%, and increased mean RR by 47%. These results demonstrate the utility of these optical techniques to evaluate the effect of pulmonary oxidative stress on tissue mitochondrial redox state in intact lungs.

  18. Cardiac Magnetic Resonance Myocardial Perfusion Reserve Index Is Reduced in Women With Coronary Microvascular Dysfunction: A National Heart, Lung and Blood Institute-Sponsored Study From the Women's Ischemia Syndrome Evaluation (WISE)

    PubMed Central

    Thomson, Louise E.J.; Wei, Janet; Agarwal, Megha; Haft-Baradaran, Afsaneh; Shufelt, Chrisandra; Mehta, Puja K.; Gill, Edward; Johnson, B. Delia; Kenkre, Tanya; Handberg, Eileen; Li, Debiao; Sharif, Behzad; Berman, Daniel S.; Petersen, John; Pepine, Carl J.; Bairey Merz, C. Noel

    2015-01-01

    Background Women with signs and symptoms of ischemia and no obstructive coronary artery disease often have coronary microvascular dysfunction (CMD), diagnosed by invasive coronary reactivity testing (CRT). While traditional noninvasive stress imaging is often normal in CMD, cardiac magnetic resonance imaging (CMRI) may be able to detect CMD in this population. Methods and Results Vasodilator stress CMRI was performed in 118 women with suspected CMD who had undergone CRT and 21 asymptomatic reference subjects. Semi quantitative evaluation of the first-pass perfusion images was completed to determine myocardial perfusion reserve index (MPRI). The relationship between CRT findings and MPRI was examined by Pearson correlations, logistic regression and sensitivity/specificity. Symptomatic women had lower mean pharmacologic stress MPRI compared to reference subjects (1.71±0.43 vs. 2.23±0.37, p<0.0001). Lower MPRI was predictive of one or more abnormal CRT variables (OR = 0.78 [0.70, 0.88], p<0.0001, c-statistic 0.78 [0.68, 0.88]). An MPRI threshold of 1.84 predicted CRT abnormality with sensitivity 73% and specificity 74%. Conclusions Noninvasive CMRI MPRI can detect CMD defined by invasive CRT. Further work is aimed to optimize the non-invasive identification and management of CMD patients. PMID:25801710

  19. Common-path Fourier domain optical coherence tomography of irradiated human skin and ventilated isolated rabbit lungs

    NASA Astrophysics Data System (ADS)

    Popp, A.; Wendel, M.; Knels, L.; Knuschke, P.; Mehner, M.; Koch, T.; Boller, D.; Koch, P.; Koch, E.

    2005-08-01

    A compact common path Fourier domain optical coherence tomography (FD-OCT) system based on a broadband superluminescence diode is used for biomedical imaging. The epidermal thickening of human skin after exposure to ultraviolet radiation is measured to proof the feasibility of FD-OCT for future substitution of invasive biopsies in a long term study on natural UV skin protection. The FD-OCT system is also used for imaging lung parenchyma. FD-OCT images of a formalin fixated lung show the same alveolar structure as scanning electron microscopy images. In the ventilated and blood-free perfused isolated rabbit lung FD-OCT is used for real-time cross-sectional image capture of alveolar mechanics throughout tidal ventilation. The alveolar mechanics changing from alternating recruitment-derecruitment at zero positive end-expiratory pressure (PEEP) to persistent recruitment after applying a PEEP of 5 cm H2O is observed in the OCT images.

  20. Can arterial spin labeling detect white matter perfusion signal?

    PubMed

    van Osch, Matthias J P; Teeuwisse, Wouter M; van Walderveen, Marianne A A; Hendrikse, Jeroen; Kies, Dennis A; van Buchem, Mark A

    2009-07-01

    Since the invention of arterial spin labeling (ASL) it has been acknowledged that ASL does not allow reliable detection of a white matter (WM) perfusion signal. However, recent developments such as pseudo-continuous labeling and background suppression have improved the quality. The goal of this research was to study the ability of these newer ASL sequences to detect WM perfusion signal. Background suppressed pseudo-continuous ASL was implemented at 3T with multislice 2D readout after 1525 ms. In five volunteers it was shown that 10 min scanning resulted in significant perfusion signal in 70% of WM voxels. Increasing the labeling and delay time did not lead to a higher percentage. In 27 normal volunteers it was found that 35 averages are necessary to detect significant WM signal, but 150 averages are needed to detect signal in the deep WM. Finally, it was shown in a patient with a cerebral arteriovenous malformation that pseudo-continuous ASL enabled the depiction of hypointense WM perfusion signal, although dynamic susceptibility contrast MRI showed that this region was merely showing delayed arrival of contrast agent than hypoperfusion. It can be concluded that, except within the deep WM, ASL is sensitive enough to detect WM perfusion signal and perfusion deficits. PMID:19365865

  1. Laser Doppler perfusion monitoring and imaging of blood microcirculation

    NASA Astrophysics Data System (ADS)

    Nilsson, Gert E.; Wardell, Karin

    1994-07-01

    Laser Doppler perfusion monitoring is a method of assessing tissue perfusion based on measurements performed using Doppler broadening of monochromatic light scattered in moving blood cells. Ever since laser Doppler perfusion monitors became available about 15 years ago they have been used in numerous applications in both clinical and laboratory settings. The high spatial resolution has in practice manifested itself as one of the main limitations of the method. The reason for this is the difficulty in attaining reproducible values at successive measurement sites because most skin tissue possesses a substantial variation in blood flow even at adjacent measurement sites. In order to overcome this difficulty the laser Doppler perfusion imager was developed. In this camera-like device, the laser beam successively scans the tissue and the Doppler components of the backscattered light are detected by a remote photodiode. After a scanning procedure is complete, a color-coded perfusion map showing the spatial variation of skin blood flow is displayed on a monitor. The operating principle and early applications of this emerging technology are addressed in further detail.

  2. Noncontact blood perfusion mapping in clinical applications

    NASA Astrophysics Data System (ADS)

    Iakovlev, Dmitry; Dwyer, Vincent; Hu, Sijung; Silberschmidt, Vadim

    2016-04-01

    Non-contact imaging photoplethysmography (iPPG) to detect pulsatile blood microcirculation in tissue has been selected as a successor to low spatial resolution and slow scanning blood perfusion techniques currently employed by clinicians. The proposed iPPG system employs a novel illumination source constructed of multiple high power LEDs with narrow spectral emission, which are temporally modulated and synchronised with a high performance sCMOS sensor. To ensure spectrum stability and prevent thermal wavelength drift due to junction temperature variations, each LED features a custom-designed thermal management system to effectively dissipate generated heat and auto-adjust current flow. The use of a multi-wavelength approach has resulted in simultaneous microvascular perfusion monitoring at various tissue depths, which is an added benefit for specific clinical applications. A synchronous detection algorithm to extract weak photoplethysmographic pulse-waveforms demonstrated robustness and high efficiency when applied to even small regions of 5 mm2. The experimental results showed evidences that the proposed system could achieve noticeable accuracy in blood perfusion monitoring by creating complex amplitude and phase maps for the tissue under examination.

  3. Bioreactor Development for Lung Tissue Engineering

    PubMed Central

    Panoskaltsis-Mortari, Angela

    2015-01-01

    Rationale Much recent interest in lung bioengineering by pulmonary investigators, industry and the organ transplant field has seen a rapid growth of bioreactor development ranging from the microfluidic scale to the human-sized whole lung systems. A comprehension of the findings from these models is needed to provide the basis for further bioreactor development. Objective The goal was to comprehensively review the current state of bioreactor development for the lung. Methods A search using PubMed was done for published, peer-reviewed papers using the keywords “lung” AND “bioreactor” or “bioengineering” or “tissue engineering” or “ex vivo perfusion”. Main Results Many new bioreactors ranging from the microfluidic scale to the human-sized whole lung systems have been developed by both academic and commercial entities. Microfluidic, lung-mimic and lung slice cultures have the advantages of cost-efficiency and high throughput analyses ideal for pharmaceutical and toxicity studies. Perfused/ventilated rodent whole lung systems can be adapted for mid-throughput studies of lung stem/progenitor cell development, cell behavior, understanding and treating lung injury and for preliminary work that can be translated to human lung bioengineering. Human-sized ex vivo whole lung bioreactors incorporating perfusion and ventilation are amenable to automation and have been used for whole lung decellularization and recellularization. Clinical scale ex vivo lung perfusion systems have been developed for lung preservation and reconditioning and are currently being evaluated in clinical trials. Conclusions Significant advances in bioreactors for lung engineering have been made at both the microfluidic and the macro scale. The most advanced are closed systems that incorporate pressure-controlled perfusion and ventilation and are amenable to automation. Ex vivo lung perfusion systems have advanced to clinical trials for lung preservation and reconditioning. The biggest

  4. Aortic arch surgery with a single centrifugal pump for selective cerebral perfusion and systemic circulation.

    PubMed

    Iwata, Keiji; Shimazaki, Yasuhisa; Sakamoto, Tomohiko; Ueda, Hideki; Nakagawa, Masashi; Yamada, Hideto; Doi, Teruo; Ooue, Takuya

    2010-01-01

    In aortic arch surgery, two pumps are required for systemic perfusion and selective cerebral perfusion (SCP). A new technique with a single centrifugal pump for systemic perfusion and SCP was developed and its efficacy and safety evaluated. This technique was adopted for total arch replacement in 22 consecutive patients with true aneurysms (13) and aortic dissection (nine) from January 2005 to January 2008. Cerebral perfusion lines branched from the main perfusion line. During SCP, right radial arterial pressure was maintained at 50 mm Hg and left common carotid arterial pressure at 60 mm Hg, and the regional cerebral oxygen saturation (rSO(2)) values were maintained at approximately >80% of the baseline value. Two operative deaths (9%) occurred due to pneumonia and hemorrhage in the left lung, respectively. Stroke occurred in one patient (5%). This simple circuit system can thus be easily and safely applied for aortic arch surgery.

  5. Prediction of Liver Function by Using Magnetic Resonance-based Portal Venous Perfusion Imaging

    PubMed Central

    Cao, Yue; Wang, Hesheng; Johnson, Timothy D.; Pan, Charlie; Hussain, Hero; Balter, James M.; Normolle, Daniel; Ben-Josef, Edgar; Ten Haken, Randall K.; Lawrence, Theodore S.; Feng, Mary

    2013-01-01

    Purpose To evaluate whether liver function can be assessed globally and spatially by using volumetric dynamic contrast-enhanced magnetic resonance imaging MRI (DCE-MRI) to potentially aid in adaptive treatment planning. Methods and Materials Seventeen patients with intrahepatic cancer undergoing focal radiation therapy (RT) were enrolled in institution review board-approved prospective studies to obtain DCE-MRI (to measure regional perfusion) and indocyanine green (ICG) clearance rates (to measure overall liver function) prior to, during, and at 1 and 2 months after treatment. The volumetric distribution of portal venous perfusion in the whole liver was estimated for each scan. We assessed the correlation between mean portal venous perfusion in the nontumor volume of the liver and overall liver function measured by ICG before, during, and after RT. The dose response for regional portal venous perfusion to RT was determined using a linear mixed effects model. Results There was a significant correlation between the ICG clearance rate and mean portal venous perfusion in the functioning liver parenchyma, suggesting that portal venous perfusion could be used as a surrogate for function. Reduction in regional venous perfusion 1 month after RT was predicted by the locally accumulated biologically corrected dose at the end of RT (P<.0007). Regional portal venous perfusion measured during RT was a significant predictor for regional venous perfusion assessed 1 month after RT (P<.00001). Global hypovenous perfusion pre-RT was observed in 4 patients (3 patients with hepatocellular carcinoma and cirrhosis), 3 of whom had recovered from hypoperfusion, except in the highest dose regions, post-RT. In addition, 3 patients who had normal perfusion pre-RT had marked hypervenous perfusion or reperfusion in low-dose regions post-RT. Conclusions This study suggests that MR-based volumetric hepatic perfusion imaging may be a biomarker for spatial distribution of liver function, which

  6. Prediction of Liver Function by Using Magnetic Resonance-based Portal Venous Perfusion Imaging

    SciTech Connect

    Cao Yue; Wang Hesheng; Johnson, Timothy D.; Pan, Charlie; Hussain, Hero; Balter, James M.; Normolle, Daniel; Ben-Josef, Edgar; Ten Haken, Randall K.; Lawrence, Theodore S.; Feng, Mary

    2013-01-01

    Purpose: To evaluate whether liver function can be assessed globally and spatially by using volumetric dynamic contrast-enhanced magnetic resonance imaging MRI (DCE-MRI) to potentially aid in adaptive treatment planning. Methods and Materials: Seventeen patients with intrahepatic cancer undergoing focal radiation therapy (RT) were enrolled in institution review board-approved prospective studies to obtain DCE-MRI (to measure regional perfusion) and indocyanine green (ICG) clearance rates (to measure overall liver function) prior to, during, and at 1 and 2 months after treatment. The volumetric distribution of portal venous perfusion in the whole liver was estimated for each scan. We assessed the correlation between mean portal venous perfusion in the nontumor volume of the liver and overall liver function measured by ICG before, during, and after RT. The dose response for regional portal venous perfusion to RT was determined using a linear mixed effects model. Results: There was a significant correlation between the ICG clearance rate and mean portal venous perfusion in the functioning liver parenchyma, suggesting that portal venous perfusion could be used as a surrogate for function. Reduction in regional venous perfusion 1 month after RT was predicted by the locally accumulated biologically corrected dose at the end of RT (P<.0007). Regional portal venous perfusion measured during RT was a significant predictor for regional venous perfusion assessed 1 month after RT (P<.00001). Global hypovenous perfusion pre-RT was observed in 4 patients (3 patients with hepatocellular carcinoma and cirrhosis), 3 of whom had recovered from hypoperfusion, except in the highest dose regions, post-RT. In addition, 3 patients who had normal perfusion pre-RT had marked hypervenous perfusion or reperfusion in low-dose regions post-RT. Conclusions: This study suggests that MR-based volumetric hepatic perfusion imaging may be a biomarker for spatial distribution of liver function, which

  7. Effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies

    NASA Astrophysics Data System (ADS)

    Murase, Kenya; Nanjo, Takafumi; Satoshi, Ii; Miyazaki, Shohei; Hirata, Masaaki; Sugawara, Yoshifumi; Kudo, Masayuki; Sasaki, Kousuke; Mochizuki, Teruhito

    2005-11-01

    The purpose of this study was to investigate the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using multi-detector row CT (MDCT). Following the standard CT perfusion study protocol, continuous (cine) scans (1 s/rotation × 60 s) consisting of four 5 mm thick contiguous slices were performed using an MDCT scanner with a tube voltage of 80 kVp and a tube current of 200 mA. We generated the simulated images with tube currents of 50 mA, 100 mA and 150 mA by adding the corresponding noise to the raw scan data of the original image acquired above using a noise simulation tool. From the original and simulated images, we generated the functional images of cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in seven patients with cerebrovascular disease, and compared the correlation coefficients (CCs) between the perfusion parameter values obtained from the original and simulated images. The coefficients of variation (CVs) in the white matter were also compared. The CC values deteriorated with decreasing tube current. There was a significant difference between 50 mA and 100 mA for all perfusion parameters. The CV values increased with decreasing tube current. There were significant differences between 50 mA and 100 mA and between 100 mA and 150 mA for CBF. For CBV and MTT, there was also a significant difference between 150 mA and 200 mA. This study will be useful for understanding the effect of x-ray tube current on the accuracy of cerebral perfusion parameters obtained by CT perfusion studies using MDCT, and for selecting the tube current.

  8. Idiopathic pulmonary fibrosis. A rare cause of scintigraphic ventilation-perfusion mismatch

    SciTech Connect

    Pochis, W.T.; Krasnow, A.Z.; Collier, B.D.; Mewissen, M.W.; Almagro, U.A.; Hellman, R.S.; Isitman, A.T. )

    1990-05-01

    A case of idiopathic pulmonary fibrosis with multiple areas of mismatch on ventilation-perfusion lung imaging in the absence of pulmonary embolism is presented. Idiopathic pulmonary fibrosis is one of the few nonembolic diseases producing a pulmonary ventilation-perfusion mismatch. In this condition, chest radiographs may not detect the full extent of disease, and xenon-133 ventilation imaging may be relatively insensitive to morbid changes in small airways. Thus, when examining patients with idiopathic pulmonary fibrosis, one should be aware that abnormal perfusion imaging patterns without matching ventilation abnormalities are not always due to embolism. In this setting, contrast pulmonary angiography is often needed for accurate differential diagnosis.

  9. Thyroid scan

    MedlinePlus

    ... thyroid; Radioactive iodine uptake and scan test - thyroid; Nuclear scan - thyroid ... the test. Ask your provider or the radiology/nuclear medicine team performing the scan about taking precautions.

  10. Nuclear Scans

    MedlinePlus

    Nuclear scans use radioactive substances to see structures and functions inside your body. They use a special ... images. Most scans take 20 to 45 minutes. Nuclear scans can help doctors diagnose many conditions, including ...

  11. Perfusion Bioreactor Module

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R.

    1990-01-01

    Perfusion bioreactor module, self-contained, closed-loop cell-culture system that operates in microgravity or on Earth. Equipment supports growth or long-term maintenance of cultures of human or other fragile cells for experiments in basic cell biology or process technology. Designed to support proliferation (initially at exponential rates of growth) of cells in complex growth medium and to maintain confluent cells in defined medium under conditions optimized to permit or encourage selected functions of cells, including secretion of products of cells into medium.

  12. Validation of nonrigid registration in pretreatment and follow-up PET/CT scans for quantification of tumor residue in lung cancer patients.

    PubMed

    Spijkerman, Jolanda; Fontanarosa, Davide; Das, Marco; Van Elmpt, Wouter

    2014-01-01

    Nonrigid registrations of pre- and postradiotherapy (RT) PET/CT scans of NSCLC patients were performed with different algorithms and validated tracking internal landmarks. Dice overlap ratios (DR) of high FDG-uptake areas in registered PET/CT scans were then calculated to study patterns of relapse. For 22 patients, pre- and post-RT PET/CT scans were registered first rigidly and then nonrigidly. For three patients, two types (based on Demons or Morphons) of nonrigid registration algorithms each with four different parameter settings were applied and assessed using landmark validation. The two best performing methods were tested on all patients, who were then classified into three groups: large (Group 1), minor (Group2) or insufficient improvement (Group 3) of registration accuracy. For Group 1 and 2, DRs between high FDG-uptake areas in pre- and post-RT PET scans were determined. Distances between corresponding landmarks on deformed pre-RT and post-RT scans decreased for all registration methods. Differences between Demons and Morphons methods were smaller than 1 mm. For Group 1, landmark distance decreased from 9.5 ± 2.1 mm to 3.8 ± 1.2 mm (mean ± 1 SD, p < 0.001), and for Group 3 from 13.6 ± 3.2 mm to 8.0 ± 2.2 mm (p = 0.025). No significant change was observed for Group 2 where distances decreased from 5.6± 1.3 mm to 4.5 ± 1.1 mm (p = 0.093). DRs of high FDG-uptake areas improved significantly after nonrigid registration for most patients in Group 1. Landmark validation of nonrigid registration methods for follow-up CT imaging in NSCLC is necessary. Nonrigid registration significantly improves matching between pre- and post-RT CT scans for a subset of patients, although not in all patients. Hence, the quality of the registration needs to be assessed for each patient individually. Successful nonrigid registration increased the overlap between pre- and post-RT high FDG-uptake regions. PMID:25207414

  13. Comparison of IGRT Registration Strategies for Optimal Coverage of Primary Lung Tumors and Involved Nodes Based on Multiple Four-Dimensional CT Scans Obtained Throughout the Radiotherapy Course

    SciTech Connect

    Mohammed, Nasiruddin; Kestin, Larry; Grills, Inga; Shah, Chirag; Glide-Hurst, Carri; Yan, Di; Ionascu, Dan

    2012-03-15

    Purpose: To investigate the impact of primary tumor and involved lymph node (LN) geometry (centroid, shape, volume) on internal target volume (ITV) throughout treatment for locally advanced non-small cell lung cancer using weekly four-dimensional computed tomography (4DCT). Methods and Materials: Eleven patients with advanced non-small cell lung cancer were treated using image-guided radiotherapy with acquisition of weekly 10-Phase 4DCTs (n = 51). Initial ITV was based on planning 4DCT. Master-ITV incorporated target geometry across the entire treatment (all 4DCTs). Geographic miss was defined as the % Master-ITV positioned outside of the initial planning ITV after registration is complete. Registration strategies considered were bony (B), primary tumor soft tissue alone (T), and registration based on primary tumor and involved LNs (T{sub L}N). Results: The % geographic miss for the primary tumor, mediastinal, and hilar lymph nodes based on each registration strategy were (1) B: 30%, 30%, 30%; (2) T: 21%, 40%, 36%; and (3) T{sub L}N: 26%, 26%, 27%. Mean geographic expansions to encompass 100% of the primary tumor and involved LNs were 1.2 {+-} 0.7 cm and 0.8 {+-} 0.3 cm, respectively, for B and T{sub L}N. Primary and involved LN expansions were 0.7 {+-} 0.5 cm and 1.1 {+-} 0.5 cm for T. Conclusion: T is best for solitary targets. When treatments include primary tumor and LNs, B and T{sub L}N provide more comprehensive geographic coverage. We have identified high % geographic miss when considering multiple registration strategies. The dosimetric implications are the subject of future study.

  14. Estimation of Lung Ventilation

    NASA Astrophysics Data System (ADS)

    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.

  15. Radiogallium scan in P. carinii pneumonia

    SciTech Connect

    Parthasarathy, K.L.; Bakshi, S.P.; Bender, M.A.

    1982-02-01

    A gallium scan performed on a patient with fever of unknown origin (FUO) revealed an abnormal uptake of radiotracer in the lungs despite negative chest roentgenographic examination and other routine diagnostic studies. Subsequent lung biopsy results confirmed the presence of Pneumocystis (P.) carinii infection. A repeat gallium scan obtained following appropriate antibiotic therapy was essentially normal. The importance of radiogallium scanning in an immunosuppressed patient with FUO is emphasized.

  16. Assessing Tumor Response to Treatment in Patients with Lung Cancer Using Dynamic Contrast-Enhanced CT

    PubMed Central

    Strauch, Louise S.; Eriksen, Rie Ø.; Sandgaard, Michael; Kristensen, Thomas S.; Nielsen, Michael B.; Lauridsen, Carsten A.

    2016-01-01

    The aim of this study was to provide an overview of the literature available on dynamic contrast-enhanced computed tomography (DCE-CT) as a tool to evaluate treatment response in patients with lung cancer. This systematic review was compiled according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Only original research articles concerning treatment response in patients with lung cancer assessed with DCE-CT were included. To assess the validity of each study we implemented Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2). The initial search yielded 651 publications, and 16 articles were included in this study. The articles were divided into groups of treatment. In studies where patients were treated with systemic chemotherapy with or without anti-angiogenic drugs, four out of the seven studies found a significant decrease in permeability after treatment. Four out of five studies that measured blood flow post anti-angiogenic treatments found that blood flow was significantly decreased. DCE-CT may be a useful tool in assessing treatment response in patients with lung cancer. It seems that particularly permeability and blood flow are important perfusion values for predicting treatment outcome. However, the heterogeneity in scan protocols, scan parameters, and time between scans makes it difficult to compare the included studies. PMID:27455330

  17. Do Diametric Measurements Provide Sufficient and Reliable Tumor Assessment? An Evaluation of Diametric, Areametric, and Volumetric Variability of Lung Lesion Measurements on Computerized Tomography Scans

    PubMed Central

    Fogarty, Edward; Beal, James; Chaudhary, Vijay

    2015-01-01

    Diametric analysis is the standard approach utilized for tumor measurement on medical imaging. However, the availability of newer more sophisticated techniques may prove advantageous. An evaluation of diameter, area, and volume was performed on 64 different lung lesions by three trained users. These calculations were obtained using a free DICOM viewer and standardized measuring procedures. Measurement variability was then studied using relative standard deviation (RSD) and intraclass correlation. Volumetric measurements were shown to be more precise than diametric. With minimal RSD and variance between different users, volumetric analysis was demonstrated as a reliable measurement technique. Additionally, the diameters were used to calculate an estimated area and volume; thereafter the estimated area and volume were compared against the actual measured values. The results in this study showed independence of the estimated and actual values. Estimated area deviated an average of 43.5% from the actual measured, and volume deviated 88.03%. The range of this variance was widely scattered and without trend. These results suggest that diametric measurements cannot be reliably correlated to actual tumor size. Access to appropriate software capable of producing volume measurements has improved drastically and shows great potential in the clinical assessment of tumors. Its applicability merits further consideration. PMID:26064117

  18. Susceptibility-Based Analysis Of Dynamic Gadolinium Bolus Perfusion MRI

    PubMed Central

    Bonekamp, David; Barker, Peter B.; Leigh, Richard; van Zijl, Peter C.M.; Li, Xu

    2014-01-01

    Purpose An algorithm is developed for the reconstruction of dynamic, gadolinium (Gd) bolus MR perfusion images of the human brain, based on quantitative susceptibility mapping (QSM). Methods The method is evaluated in 5 perfusion scans obtained from 4 different patients scanned at 3T, and compared to the conventional analysis based on changes in the transverse relaxation rate ΔR2* and to theoretical predictions. QSM images were referenced to ventricular CSF for each dynamic of the perfusion sequence. Results Images of cerebral blood flow and blood volume were successfully reconstructed from the QSM-analysis, and were comparable to those reconstructed using ΔR2*. The magnitudes of the Gd-associated susceptibility effects in gray and white matter were consistent with theoretical predictions. Conclusion QSM-based analysis may have some theoretical advantages compared to ΔR2*, including a simpler relationship between signal change and Gd concentration. However, disadvantages are its much lower contrast-to-noise ratio, artifacts due to respiration and other effects, and more complicated reconstruction methods. More work is required to optimize data acquisition protocols for QSM-based perfusion imaging. PMID:24604343

  19. [Extracorporeal perfusion of the sheep rumen].

    PubMed

    Leng, L; Bajo, M; Várady, J; Szányiová, M

    1977-06-01

    We constructed a modified perfusion apparatus and elaborated a method of extracorporal perfusion of the rumen of sheep. As perfusates we used the bovine plasma diluted in a ratio of 1:1 of an isotonic sodium chloride (NaCl) solution and the whole autologous blood. Transaminases GOT and GPT, ammonia and pH were determined in the perfusate. The different perfusions were evaluated according to previously determined perfusion conditions and criteria. A subject for discussion is the question of suitability of the parameters under examination for judging the state of the perfused organ. The described method is suitable for the study of metabolical processes in the rumen wal.

  20. A study on cerebral hemodynamic analysis of moyamoya disease by using perfusion MRI

    NASA Astrophysics Data System (ADS)

    Dong, Kyung-Rae; Goo, Eun-Hoe; Lee, Jae-Seung; Chung, Woon-Kwan

    2013-10-01

    This study examined the clinical applications of perfusion magnetic resonance imaging (MRI) in patients with moyamoya disease (MMD). Twenty-two patients with moyamoya disease (9 men and 13 women) with a mean age of 9.3 years (range: 4-22 years) were enrolled in this study. Perfusion MRI was performed by scanning the patients7.5 cm upward from the base of the cerebellum before their being process for post-treatment. The scan led to the acquisition of the following four map images: the cerebral blood volume (CBV), the cerebral blood flow (CBF), the mean transit time (MTT) for the contrast medium, and the time to peak (TTP) for the contrast medium. The lesions were assessed using the CBV, the CBF, the MTT and the TTP maps of perfusion MRI; the MTT and the TTP were measured in the lesion areas, as well as in the normal and the symmetric areas. Perfusion defects were recognizable in all four perfusion MRI maps, and the MTT and the TTP showed a conspicuous delay in the parts where perfusion defects were recognized. The MTT and the TTP images of perfusion MRI reflected a significant correlation between the degrees of stenosis and occlusion in the posterior cerebral artery (PCA), as well as the development of collateral vessels. The four perfusion MRI maps could be used to predict the degrees of stenosis and occlusion in the posterior circulation, as well as the development of the collateral vessels, which enabled a hemodynamic evaluation of the parts with perfusion defects. Overall, perfusion MRI is useful for the diagnosis and the treatment of moyamoya disease and can be applied to clinical practice.

  1. Distributed perfusion educational model: a shift in perfusion economic realities.

    PubMed

    Austin, Jon W; Evans, Edward L; Hoerr, Harry R

    2005-12-01

    In recent years, a steady decline in the number of perfusion education programs in the United States has been noted. At the same time, there has been a parallel decline in the number of students graduated from perfusion educational programs in the United States. Also, as noted by several authors, there has been an increase in demand for perfusion graduates. The decline in programs and graduates has also been noted in anesthesia and surgical residency programs. The shift is caused by a combination of economic and clinical factors. First, decreased reimbursement has led to reallocation of hospital resources. Second, the original enthusiasm for beating heart coronary artery bypass surgery was grossly overestimated and has led to further reallocation of hospital resources and denigration of cardiopulmonary bypass. This paper describes two models of perfusion education programs: serial perfusion education model (SPEM) and the distributed perfusion education model (DPEM). Arguments are presented that the SPEM has some serious limitations and challenges for long-term economic survival. The authors feel the DPEM along with dependence on tuition funding can survive the current clinical and economic conditions and allow the profession to adapt to changes in scope of practice. PMID:16524152

  2. Gallium scan

    MedlinePlus

    Liver gallium scan; Bony gallium scan ... You will get a radioactive material called gallium injected into your vein. The gallium travels through the bloodstream and collects in the bones and certain organs. Your health care provider will ...

  3. Measuring blood delivery to solitary pulmonary nodules using perfusion magnetic resonance imaging

    NASA Astrophysics Data System (ADS)

    Zheng, Wei; Wang, Zhifeng; Shen, Li; Gao, Ling; Ford, James C.; Makedon, Fillia S.; Pearlman, Justin D.

    2006-03-01

    With perfusion magnetic resonance imaging (pMRI), perfusion describes the amount of blood passing through a block of tissue in a certain period of time. In pMRI, the tissue having more blood passing through will show higher intensity value as more contrast-labeled blood arrives. Perfusion reflects the delivery of essential nutrients to a block of tissue, and is an important parameter for the tissue status. Considering solitary pulmonary nodules (SPN), perfusion differences between malignant and benign nodules have been studied by different techniques. Much effort has been put into its characterization. In this paper, we proposed and implemented extraction of the SPN time intensity profile to measure blood delivery to solitary pulmonary nodules, describing their perfusion effects. In this method, a SPN time intensity profile is created based on intensity values of the solitary pulmonary nodule in lung pMRI images over time. This method has two steps: nodule tracking and profile clustering. Nodule tracking aligns the solitary pulmonary nodule in pMRI images taken at different time points, dealing with nodule movement resulted from breathing and body movement. Profile clustering implements segmentation of the nodule region and extraction of the time intensity profile of a solitary pulmonary nodule. SPN time intensity profiles reflect patterns of blood delivery to solitary pulmonary nodules, giving us a description of perfusion effect and indirect evidence of tumor angiogenesis. Analysis on SPN time intensity profiles will help the diagnosis of malignant nodules for early lung cancer detection.

  4. Asymptomatic Unilateral Hyperlucent Lung in a Prospective Kidney Donor.

    PubMed

    Lunia, Prajay; Karkhanis, Vinaya; Joshi, J M

    2015-09-01

    A 50 year old lady, prospective kidney donor was referred to our department for opinion in view of abnormal clinical findings during preoperative evaluation. She was asymptomatic from respiratory point of view. Her vital parameters were normal and on auscultation found to have decreased breath sounds and fine crackles throughout left hemithorax. Chest x-ray (CXR) showed left sided hyperlucency with small hilum (Figure 1). High resolution computed tomography (HRCT) showed scattered areas of bronchiectasis with associated air trapping throughout left lung with small left pulmonary artery (Figure 2). Sputum for acid fast bacilli (AFB) was negative. Spirometry showed moderate obstructive abnormality with forced expiratory volume in one second (FEV1) - 51% predicted, forced vital capacity (FVC) - 60% and FEV1/FVC - 76% with no bronchodilator reversibility. On post bronchodilator study there was paradoxical fall in FEV1/FVC to 72% consistent with small airway disease. Arterial blood gas analysis was normal. Technetium (Tc) 99m MAA lung perfusion scan (Figure3) showed normal perfusion of right lung contributing 75.4% of relative function and left lung contributing only 24.6%. Diagnosis of Swyer-James-MacLeod syndrome (SJMS) probably due to a childhood viral infection was made. Operative complications in such cases like difficult weaning and extubation, post-operative respiratory infections, collapse and respiratory failure are likely. However, our patient had an uneventful operative and post-operative course. SJMS is characterized by unilateral hyperlucency of a part of or the entire lung which was first described in 1953 by Swyer and James and later in 1954 by Macleod.1,2 It is considered to be an acquired disease as a result of post-infectious obliterative bronchiolitis. Productive cough, shortness of breath and sometimes hemoptysis are presenting symptoms. Some patients are asymptomatic and not diagnosed until they are adults.3 Radiologically it presents as predominant

  5. Bone scanning.

    PubMed

    Greenfield, L D; Bennett, L R

    1975-03-01

    Scanning is based on the uptake of a nuclide by the crystal lattice of bone and is related to bone blood flow. Cancer cells do not take up the tracer. Normally, the scan visualizes the highly vascular bones. Scans are useful and are indicated in metastatic bone disease, primary bone tumors, hematologic malignancies and some non-neoplastic diseases. The scan is more sensitive than x-ray in the detection of malignant diseases of the skeleton. PMID:1054210

  6. 4D micro-CT-based perfusion imaging in small animals

    NASA Astrophysics Data System (ADS)

    Badea, C. T.; Johnston, S. M.; Lin, M.; Hedlund, L. W.; Johnson, G. A.

    2009-02-01

    Quantitative in-vivo imaging of lung perfusion in rodents can provide critical information for preclinical studies. However, the combined challenges of high temporal and spatial resolution have made routine quantitative perfusion imaging difficult in rodents. We have recently developed a dual tube/detector micro-CT scanner that is well suited to capture first-pass kinetics of a bolus of contrast agent used to compute perfusion information. Our approach is based on the paradigm that the same time density curves can be reproduced in a number of consecutive, small (i.e. 50μL) injections of iodinated contrast agent at a series of different angles. This reproducibility is ensured by the high-level integration of the imaging components of our system, with a micro-injector, a mechanical ventilator, and monitoring applications. Sampling is controlled through a biological pulse sequence implemented in LabVIEW. Image reconstruction is based on a simultaneous algebraic reconstruction technique implemented on a GPU. The capabilities of 4D micro-CT imaging are demonstrated in studies on lung perfusion in rats. We report 4D micro-CT imaging in the rat lung with a heartbeat temporal resolution of 140 ms and reconstructed voxels of 88 μm. The approach can be readily extended to a wide range of important preclinical models, such as tumor perfusion and angiogenesis, and renal function.

  7. Inhomogeneity of pulmonary perfusion during sustained microgravity on SLS-1

    NASA Technical Reports Server (NTRS)

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

    1994-01-01

    We studied the effects of gravity on the inhomogeneity of pulmonary perfusion in humans by performing hyperventilation-breath-hold single-breath measurements before, during, and after 9 days of continuous exposure to microgravity during the Spacelab Life Sciences-1 (SLS-1) mission. In microgravity the indicators of inhomogeneity of perfusion, especially the size of cardiogenic oscillations in expired CO2 and the height of phase IV, were markedly reduced. Cardiogenic oscillations were reduced to approximately 60% of their preflight standing size, and the height of phase IV was between 0 and -8% (a terminal fall became a small terminal rise) of the preflight standing value. The terminal change in expired CO2 was nearly abolished in microgravity, indicating more uniformity of blood flow between lung units that close and those that remain open at the end of expiration. A possible explanation of this observation is the disappearance of gravity-dependent topographic inequality of blood flow. The residual cardiogenic oscillations in expired CO2 imply a persisting inhomogeneity of perfusion in the absence of gravity, probably in lung regions that are not within the same acinus.

  8. Cerebral perfusion in children with Alice in Wonderland syndrome.

    PubMed

    Kuo, Y T; Chiu, N C; Shen, E Y; Ho, C S; Wu, M C

    1998-08-01

    Alice in Wonderland syndrome (AIWS) is characterized by visual hallucinations and bizarre perceptual distortions. Technetium-99m hexamethylpropyleneamine tomography (SPECT) brain scans were performed in four patients during the acute stage of AIWS. Two patients were demonstrated to have Epstein-Barr virus infections. One had abnormal (EEG) findings. The visual-evoked potential, cranial CT, and MRI findings were negative. The decreased cerebral perfusion areas in all patients were near the visual tract and visual cortex. All involved some regions of the temporal lobe. In most patients with AIWS, the EEG, CT, and MRI are unable to determine the precise pathologic areas. However, a SPECT brain scan may demonstrate abnormal perfusion areas and explain the clinical presentations. PMID:9744628

  9. Hydrostatic determinants of cerebral perfusion

    SciTech Connect

    Wagner, E.M.; Traystman, R.J.

    1986-05-01

    We examined the cerebral blood flow response to alterations in perfusion pressure mediated through decreases in mean arterial pressure, increases in cerebrospinal fluid (CSF) pressure, and increases in jugular venous (JV) pressure in 42 pentobarbital anesthetized dogs. Each of these three pressures was independently controlled. Cerebral perfusion pressure was defined as mean arterial pressure minus JV or CSF pressure, depending on which was greater. Mean hemispheric blood flow was measured with the radiolabeled microsphere technique. Despite 30-mm Hg reductions in mean arterial pressure or increases in CSF or JV pressure, CBF did not change as long as the perfusion pressure remained greater than approximately 60 mm Hg. However, whenever perfusion pressure was reduced to an average of 48 mm Hg, cerebral blood flow decreased 27% to 33%. These results demonstrate the capacity of the cerebral vascular bed to respond similarly to changes in the perfusion pressure gradient obtained by decreasing mean arterial pressure, increasing JV pressure or increasing CSF pressure, and thereby support the above definition of cerebral perfusion pressure.

  10. Irreversible Electroporation in a Swine Lung Model

    SciTech Connect

    Dupuy, Damian E.; Aswad, Bassam; Ng, Thomas

    2011-04-15

    Purpose: This study was designed to evaluate the safety and tissue effects of IRE in a swine lung model. Methods: This study was approved by the institutional animal care committee. Nine anesthetized domestic swine underwent 15 percutaneous irreversible electroporation (IRE) lesion creations (6 with bipolar and 3 with 3-4 monopolar electrodes) under fluoroscopic guidance and with pancuronium neuromuscular blockade and EKG gating. IRE electrodes were placed into the central and middle third of the right mid and lower lobes in all animals. Postprocedure PA and lateral chest radiographs were obtained to evaluate for pneumothorax. Three animals were sacrificed at 2 weeks and six at 4 weeks. Animals underwent high-resolution CT scanning and PA and lateral radiographs 1 h before sacrifice. The treated lungs were removed en bloc, perfused with formalin, and sectioned. Gross pathologic and microscopic changes after standard hematoxylin and eosin staining were analyzed within the areas of IRE lesion creation. Results: No significant adverse events were identified. CT showed focal areas of spiculated high density ranging in greatest diameter from 1.1-2.2 cm. On gross inspection of the sectioned lung, focal areas of tan discoloration and increased density were palpated in the areas of IRE. Histological analysis revealed focal areas of diffuse alveolar damage with fibrosis and inflammatory infiltration that respected the boundaries of the interlobular septae. No pathological difference could be discerned between the 2- and 4-week time points. The bronchioles and blood vessels within the areas of IRE were intact and did not show signs of tissue injury. Conclusion: IRE creates focal areas of diffuse alveolar damage without creating damage to the bronchioles or blood vessels. Short-term safety in a swine model appears to be satisfactory.

  11. Quality Assurance of 4D-CT Scan Techniques in Multicenter Phase III Trial of Surgery Versus Stereotactic Radiotherapy (Radiosurgery or Surgery for Operable Early Stage (Stage 1A) Non-Small-Cell Lung Cancer [ROSEL] Study)

    SciTech Connect

    Hurkmans, Coen W.; Lieshout, Maarten van; Schuring, Danny; Heumen, Marielle J.T. van; Cuijpers, Johan P.; Lagerwaard, Frank J.; Widder, Joachim; Heide, Uulke A. van der; Senan, Suresh

    2011-07-01

    Purpose: To determine the accuracy of four-dimensional computed tomography (4D-CT) scanning techniques in institutions participating in a Phase III trial of surgery vs. stereotactic radiotherapy (SBRT) for lung cancer. Methods and Materials: All 9 centers performed a 4D-CT scan of a motion phantom (Quasar, Modus Medical Devices) in accordance with their in-house imaging protocol for SBRT. A cylindrical cedar wood insert with plastic spheres of 15 mm (o15) and 30 mm (o30) diameter was moved in a cosine-based pattern, with an extended period in the exhale position to mimic the actual breathing motion. A range of motion of R = 15 and R = 25 mm and breathing period of T = 3 and T = 6 s were used. Positional and volumetric imaging accuracy was analyzed using Pinnacle version 8.1x at various breathing phases, including the mid-ventilation phase and maximal intensity projections of the spheres. Results: Imaging using eight CT scanners (Philips, Siemens, GE) and one positron emission tomography-CT scanner (Institution 3, Siemens) was investigated. The imaging protocols varied widely among the institutions. No strong correlation was found between the specific scan protocol parameters and the observed results. Deviations in the maximal intensity projection volumes averaged 1.9% (starting phase of the breathing cycle [o]15, R = 15), 12.3% (o15, R = 25), and -0.9% (o30, R = 15). The end-expiration volume deviations (13.4%, o15 and 2.5%, o30), were, on average, smaller than the end-inspiration deviations (20.7%, o15 and 4.5%, o30), which, in turn, were smaller than the mid-ventilation deviations (32.6%, o15 and 8.0%, o30). A slightly larger variation in the mid-ventilation origin position was observed (mean, -0.2 mm; range, -3.6-4.2) than in the maximal intensity projection origin position (mean, -0.1 mm; range, -2.5-2.5). The range of motion was generally underestimated (mean, -1.5 mm; range, -5.5-1). Conclusions: Notable differences were seen in the 4D-CT imaging protocols

  12. PET scan

    MedlinePlus

    ... to check how well you are responding to treatment for cancer or another illness. ... Ettinger DS. Lung cancer and other pulmonary neoplasms. In: Goldman L, ... Radiology: A Textbook of Medical Imaging . 6th ed. New ...

  13. Lung Emergencies

    MedlinePlus

    ... Emergencies Cardiac Emergencies Eye Emergencies Lung Emergencies Surgeries Lung Emergencies People with Marfan syndrome can be at ... should be considered an emergency. Symptoms of sudden lung collapse (pneumothorax) Symptoms of a sudden lung collapse ...

  14. Lung Cancer

    MedlinePlus

    ... version of this page please turn Javascript on. Lung Cancer What is Lung Cancer? How Tumors Form The body is made ... button on your keyboard.) Two Major Types of Lung Cancer There are two major types of lung ...

  15. Lung metastases

    MedlinePlus

    Metastases to the lung; Metastatic cancer to the lung ... Metastatic tumors in the lungs are cancers that developed at other places in the body (or other parts of the lungs) and spread through the ...

  16. Association Between Pulmonary Uptake of Fluorodeoxyglucose Detected by Positron Emission Tomography Scanning After Radiation Therapy for Non-Small-Cell Lung Cancer and Radiation Pneumonitis

    SciTech Connect

    Mac Manus, Michael P.; Ding Zhe; Hogg, Annette; Herschtal, Alan; Binns, David; Ball, David L.; Hicks, Rodney J.

    2011-08-01

    Purpose: To study the relationship between fluorodeoxyglucose (FDG) uptake in pulmonary tissue after radical radiation therapy (RT) and the presence and severity of radiation pneumonitis. Methods and Materials: In 88 consecutive patients, {sup 18}F-FDG-positron emission tomography was performed at a median of 70 days after completion of RT. Patients received 60 Gy in 30 fractions, and all but 15 had concurrent platinum-based chemotherapy. RT-induced pulmonary inflammatory changes occurring within the radiation treatment volume were scored, using a visual (0 to 3) radiotoxicity grading scale, by an observer blinded to the presence or absence of clinical radiation pneumonitis. Radiation pneumonitis was retrospectively graded using the Radiation Therapy Oncology Group (RTOG) scale by an observer blinded to the PET radiotoxicity score. Results: There was a significant association between the worst RTOG pneumonitis grade occurring at any time after RT and the positron emission tomograph (PET) radiotoxicity grade (one-sided p = 0.033). The worst RTOG pneumonitis grade occurring after the PET scan was also associated with the PET radiotoxicity grade (one-sided p = 0.035). For every one-level increase in the PET toxicity scale, the risk of a higher RTOG radiation pneumonitis score increased by approximately 40%. The PET radiotoxicity score showed no significant correlation with the duration of radiation pneumonitis. Conclusions: The intensity of FDG uptake in pulmonary tissue after RT determined using a simple visual scoring system showed significant correlation with the presence and severity of radiation pneumonitis. {sup 18}F-FDG-PET may be useful in the prediction, diagnosis and therapeutic monitoring of radiation pneumonitis.

  17. Prone positioning improves distribution of pulmonary perfusion: noninvasive magnetic resonance imaging study in healthy humans.

    PubMed

    Suzuki, Hisashi; Sato, Yukio; Shindo, Masashi; Yoshioka, Hiroshi; Mizutani, Taro; Onizuka, Masataka; Sakakibara, Yuzuru

    2008-03-01

    The purpose of this study was to evaluate the effects of prone positioning on pulmonary perfusion using flow-sensitive alternating inversion recovery (FAIR), a noninvasive magnetic resonance imaging technique that requires no contrast medium. Seven healthy volunteers were studied in the supine and prone positions under three respiratory conditions: normal breathing of room air, unassisted breathing of 45% O2, and controlled mechanical ventilation (CMV) with positive end-expiratory pressure. Signal intensities (SIs) were obtained from ventral, middle, and dorsal regions on sagittal lung images and dependent/nondependent SI ratios were calculated to evaluate pulmonary perfusion distribution. In the supine position, SIs increased significantly from the ventral to dorsal region under all three respiratory conditions and prone positioning inverted the perfusion distribution under all conditions. Right lung SI ratios were 2.34 +/- 0.29, 2.74 +/- 0.66, and 2.42 +/- 0.73 in the supine position and 1.68 +/- 0.48, 1.78 +/- 0.36, and 1.92 +/- 0.21 in prone for room air, 45% O2, and CMV, respectively. The difference between supine and prone positions was statistically significant. The left lung showed a similar pattern and the difference was significant only under CMV. No difference was observed between the different respiratory conditions in both lungs. This study demonstrated that the distribution of pulmonary perfusion was more uniform in prone than in the supine position.

  18. Evaluation of CT Perfusion Biomarkers of Tumor Hypoxia

    PubMed Central

    Qi, Qi; Yeung, Timothy Pok Chi; Lee, Ting-Yim; Bauman, Glenn; Crukley, Cathie; Morrison, Laura; Hoffman, Lisa; Yartsev, Slav

    2016-01-01

    Background Tumor hypoxia is associated with treatment resistance to cancer therapies. Hypoxia can be investigated by immunohistopathologic methods but such procedure is invasive. A non-invasive method to interrogate tumor hypoxia is an attractive option as such method can provide information before, during, and after treatment for personalized therapies. Our study evaluated the correlations between computed tomography (CT) perfusion parameters and immunohistopathologic measurement of tumor hypoxia. Methods Wistar rats, 18 controls and 19 treated with stereotactic radiosurgery (SRS), implanted with the C6 glioma tumor were imaged using CT perfusion on average every five days to monitor tumor growth. A final CT perfusion scan and the brain were obtained on average 14 days (8–22 days) after tumor implantation. Tumor hypoxia was detected immunohistopathologically with pimonidazole. The tumor, necrotic, and pimonidazole-positive areas on histology samples were measured. Percent necrotic area and percent hypoxic areas were calculated. Tumor volume (TV), blood flow (BF), blood volume (BV), and permeability-surface area product (PS) were obtained from the CT perfusion studies. Correlations between CT perfusion parameters and histological parameters were assessed by Spearman’s ρ correlation. A Bonferroni-corrected P value < 0.05 was considered significant. Results BF and BV showed significant correlations with percent hypoxic area ρ = -0.88, P < 0.001 and ρ = -0.81, P < 0.001, respectively, for control animals and ρ = -0.7, P < 0.001 and ρ = -0.6, P = 0.003, respectively, for all animals, while TV and BV were correlated (ρ = -0.64, P = 0.01 and ρ = -0.43, P = 0.043, respectively) with percent necrotic area. PS was not correlated with either percent necrotic or percent hypoxic areas. Conclusions Percent hypoxic area provided significant correlations with BF and BV, suggesting that CT perfusion parameters are potential non-invasive imaging biomarkers of tumor

  19. Optical investigation of functional structures in isolated perfused pig heart

    NASA Astrophysics Data System (ADS)

    Rauh, Robert; Boehnert, Markus; Mahlke, Christine; Kessler, Manfred D.

    2000-11-01

    Light scattering in tissue of mammals and humans is affected by subcellular structures. Since these structures correlate well with the status of cells and tissue, light scattering seems to be ideal for monitoring of functional tissue state. By use of EMPHO SSK Oxyscan we investigated functional parameters in a novel kind of isolated perfused pig heart model. In this perfusion model we use organs obtained by the local slaughterhouse that are reanimated at our institute by application of a heart-lung machine. By creating 3D-images of tissue scattering we found an interesting relation between anatomical structures of myocardium and the 3D-images. Additionally, we detected coherence between backscattered light intensity and functional tissue status. Furthermore, we got a sight into the redox state of cytochrome aa3, b and c by creating difference spectra. We believe that this new kind of tissue imaging method will give us the opportunity to get new insights into myocardial function.

  20. Pulmonary nuclear medicine: Techniques in diagnosis of lung disease

    SciTech Connect

    Atkins, H.L.

    1984-01-01

    This book presents papers on the application of nuclear medicine to the diagnosis of lung diseases. Topics considered include lung physiology and anatomy, radiopharmaceuticals in pulmonary medicine, pulmonary embolism, obstructive pulmonary disease, diffuse infiltrative lung disease, pneumoconioses, tumor localization scans in primary lung tumors, the interactions of heart diseases and lung diseases on radionuclide tests of lung anatomy and function, radionuclide imaging in pediatric lung diseases, and future possibilities in pulmonary nuclear medicine.

  1. Lung cancer

    SciTech Connect

    Aisner, J.

    1985-01-01

    This book contains 13 chapters. Some of the chapter titles are: The Pathology of Lung Cancer; Radiotherapy for Non-Small-Cell Cancer of the Lung; Chemotherapy for Non-Small-Cell Lung Cancer; Immunotherapy in the Management of Lung Cancer; Preoperative Staging and Surgery for Non-Small-Cell Lung Cancer; and Prognostic Factors in Lung Cancer.

  2. Moving Back to the Future: Use of Organ Care System Lung for Lobectomy Before Lobar Lung Transplantation.

    PubMed

    Sabashnikov, Anton; Zeriouh, Mohamed; Mohite, Prashant N; Patil, Nikhil P; García-Sáez, Diana; Schmack, Bastian; Soresi, Simona; Dohmen, Pascal M; Popov, Aron-Frederik; Weymann, Alexander; Simon, André R; De Robertis, Fabio

    2016-01-01

    BACKGROUND Lung transplantation remains the gold standard treatment for patients with end-stage lung disease. Lobar lung transplantation allows for transplantation of size-mismatch donor lungs in small recipients; however, donor lung volume reduction represents a challenging surgical technique. In this paper we present our initial experience with bilateral lobectomy in donor lungs before lobar lung transplantation using normothermic perfusion on the Organ Care System (OCS) Lung. MATERIAL AND METHODS Specifics of the surgical technique for donor lung instrumentation on the OCS, lobar dissection on the OCS, and right and left donor lobectomies are presented in detail. RESULTS Potential advantages of the use of the OCS for lobectomy for lobar lung transplantation are described in this section. Donor lung volume reduction utilizing OCS appeared to be easier and safer compared to the conventional cold storage technique, due to continuous perfusion of the lungs with blood and well-distended vessels that offer the feel of live lobectomy. Moreover, the OCS represents a platform for donor organ assessment and optimization of its function before transplantation. CONCLUSIONS Donor lung volume reduction was safe and feasible utilizing the OCS, which could be a useful tool for volume reduction in cases of size mismatch. Further research is needed to evaluate early and long-term results after lobar lung transplantation using the OCS in clinical studies. PMID:27425199

  3. Moving Back to the Future: Use of Organ Care System Lung for Lobectomy Before Lobar Lung Transplantation

    PubMed Central

    Sabashnikov, Anton; Zeriouh, Mohamed; Mohite, Prashant N.; Patil, Nikhil P.; García-Sáez, Diana; Schmack, Bastian; Soresi, Simona; Dohmen, Pascal M.; Popov, Aron-Frederik; Weymann, Alexander; Simon, André R.; De Robertis, Fabio

    2016-01-01

    Background Lung transplantation remains the gold standard treatment for patients with end-stage lung disease. Lobar lung transplantation allows for transplantation of size-mismatch donor lungs in small recipients; however, donor lung volume reduction represents a challenging surgical technique. In this paper we present our initial experience with bilateral lobectomy in donor lungs before lobar lung transplantation using normothermic perfusion on the Organ Care System (OCS) Lung. Material/Methods Specifics of the surgical technique for donor lung instrumentation on the OCS, lobar dissection on the OCS, and right and left donor lobectomies are presented in detail. Results Potential advantages of the use of the OCS for lobectomy for lobar lung transplantation are described in this section. Donor lung volume reduction utilizing OCS appeared to be easier and safer compared to the conventional cold storage technique, due to continuous perfusion of the lungs with blood and well-distended vessels that offer the feel of live lobectomy. Moreover, the OCS represents a platform for donor organ assessment and optimization of its function before transplantation. Conclusions Donor lung volume reduction was safe and feasible utilizing the OCS, which could be a useful tool for volume reduction in cases of size mismatch. Further research is needed to evaluate early and long-term results after lobar lung transplantation using the OCS in clinical studies. PMID:27425199

  4. SU-E-J-120: Comparing 4D CT Computed Ventilation to Lung Function Measured with Hyperpolarized Xenon-129 MRI

    SciTech Connect

    Neal, B; Chen, Q

    2015-06-15

    Purpose: To correlate ventilation parameters computed from 4D CT to ventilation, profusion, and gas exchange measured with hyperpolarized Xenon-129 MRI for a set of lung cancer patients. Methods: Hyperpolarized Xe-129 MRI lung scans were acquired for lung cancer patients, before and after radiation therapy, measuring ventilation, perfusion, and gas exchange. In the standard clinical workflow, these patients also received 4D CT scans before treatment. Ventilation was computed from 4D CT using deformable image registration (DIR). All phases of the 4D CT scan were registered using a B-spline deformable registration. Ventilation at the voxel level was then computed for each phase based on a Jacobian volume expansion metric, yielding phase sorted ventilation images. Ventilation based upon 4D CT and Xe-129 MRI were co-registered, allowing qualitative visual comparison and qualitative comparison via the Pearson correlation coefficient. Results: Analysis shows a weak correlation between hyperpolarized Xe-129 MRI and 4D CT DIR ventilation, with a Pearson correlation coefficient of 0.17 to 0.22. Further work will refine the DIR parameters to optimize the correlation. The weak correlation could be due to the limitations of 4D CT, registration algorithms, or the Xe-129 MRI imaging. Continued development will refine parameters to optimize correlation. Conclusion: Current analysis yields a minimal correlation between 4D CT DIR and Xe-129 MRI ventilation. Funding provided by the 2014 George Amorino Pilot Grant in Radiation Oncology at the University of Virginia.

  5. [Respiratory and extracorporeal lung support].

    PubMed

    Lotz, Christopher; Roewer, Norbert; Muellenbach, Ralf M

    2016-09-01

    Mechanical ventilation is the most commonly used form of respiratory support to restore or maintain adequate gas exchange. However, mechanical ventilation does not provide a physiological form of breathing. Neither does it provide an optimal ventilation / perfusion ratio due to passive movement of the diagphragm favoring the non-dependent parts of the lung. Furthermore, patients are in danger of ventilator-associated/induced lung injury (VALI/VILI). Hence, lung protective ventilation is mandatory in patients with an acute respiratory distress syndrome (ARDS) and should likewise be used in the operating room. Extracorporeal pulmonary support is required in case mechanical ventilation is unable to secure sufficient gas exchange or VILI is imminent. Venovenous extracorporeal membrane oxygenation (vvECMO) acts as lung replacement therapy and may improve survival along with treatment in an ARDS-center. PMID:27631452

  6. Perfusion from angiogram and a priori (PAP) with temporal regularization

    NASA Astrophysics Data System (ADS)

    Taguchi, Katsuyuki; Geschwind, Jean-Francois H.

    2009-02-01

    Perfusion imaging is often used for diagnosis and for assessment of the response to the treatment. If perfusion can be measured during interventional procedures, it could lead to quantitative, more efficient and accurate treatment; however, imaging modalities that allow continuous dynamic scanning are not available in most of procedure rooms. Thus, we developed a method to measure the perfusion-time attenuation curves (TACs)-of regions-of-interest (ROIs) using xray C-arm angiography system with no gantry rotation but with a priori. The previous study revealed a problem of large oscillations in the estimated TACs and the lack of comparison with CT-based approaches. Thus the purposes of this study were (1) to reduce the variance of TDCs; and (2) to compare the performance of the improved PAP with that of the CT-based perfusion method. Our computer simulation study showed that the standard deviation of PAP method was decreased by 10.7-59.0% and that it outperformed (20× or 200× times) higher dose CT methods in terms of the accuracy, variance, and the temporal resolution.

  7. Modelling Brain Temperature and Perfusion for Cerebral Cooling

    NASA Astrophysics Data System (ADS)

    Blowers, Stephen; Valluri, Prashant; Marshall, Ian; Andrews, Peter; Harris, Bridget; Thrippleton, Michael

    2015-11-01

    Brain temperature relies heavily on two aspects: i) blood perfusion and porous heat transport through tissue and ii) blood flow and heat transfer through embedded arterial and venous vasculature. Moreover brain temperature cannot be measured directly unless highly invasive surgical procedures are used. A 3D two-phase fluid-porous model for mapping flow and temperature in brain is presented with arterial and venous vessels extracted from MRI scans. Heat generation through metabolism is also included. The model is robust and reveals flow and temperature maps in unprecedented 3D detail. However, the Karmen-Kozeny parameters of the porous (tissue) phase need to be optimised for expected perfusion profiles. In order to optimise the K-K parameters a reduced order two-phase model is developed where 1D vessels are created with a tree generation algorithm embedded inside a 3D porous domain. Results reveal that blood perfusion is a strong function of the porosity distribution in the tissue. We present a qualitative comparison between the simulated perfusion maps and those obtained clinically. We also present results studying the effect of scalp cooling on core brain temperature and preliminary results agree with those observed clinically.

  8. Impact of pretreatment whole-tumor perfusion computed tomography and 18F-fluorodeoxyglucose positron emission tomography/computed tomography measurements on local control of non–small cell lung cancer treated with stereotactic body radiotherapy

    PubMed Central

    Aoki, Masahiko; Akimoto, Hiroyoshi; Sato, Mariko; Hirose, Katsumi; Kawaguchi, Hideo; Hatayama, Yoshiomi; Seino, Hiroko; Kakehata, Shinya; Tsushima, Fumiyasu; Fujita, Hiromasa; Fujita, Tamaki; Fujioka, Ichitaro; Tanaka, Mitsuki; Miura, Hiroyuki; Ono, Shuichi; Takai, Yoshihiro

    2016-01-01

    This study aimed to investigate the correlation between the average iodine density (AID) detected by dual-energy computed tomography (DE-CT) and the maximum standardized uptake value (SUVmax) yielded by [18F] fluorodeoxyglucose positron emission tomography (18F-FDG PET) for non–small cell lung cancer (NSCLC) treated with stereotactic body radiotherapy (SBRT). Seventy-four patients with medically inoperable NSCLC who underwent both DE-CT and 18F-FDG PET/CT before SBRT (50‒60 Gy in 5‒6 fractions) were followed up after a median interval of 24.5 months. Kaplan–Meier analysis was used to determine associations between local control (LC) and variables, including AID, SUVmax, tumor size, histology, and prescribed dose. The median AID and SUVmax were 18.64 (range, 1.18–45.31) (100 µg/cm3) and 3.2 (range, 0.7–17.6), respectively. No correlation was observed between AID and SUVmax. Two-year LC rates were 96.2% vs 75.0% (P = 0.039) and 72.0% vs 96.2% (P = 0.002) for patients classified according to high vs low AID or SUVmax, respectively. Two-year LC rates for patients with adenocarcinoma vs squamous cell carcinoma vs unknown cancer were 96.4% vs 67.1% vs 92.9% (P = 0.008), respectively. Multivariate analysis identified SUVmax as a significant predictor of LC. The 2-year LC rate was only 48.5% in the subgroup of lower AID and higher SUVmax vs >90% (range, 94.4–100%) in other subgroups (P = 0.000). Despite the short follow-up period, a reduction in AID and subsequent increase in SUVmax correlated significantly with local failure in SBRT-treated NSCLC patients. Further studies involving larger populations and longer follow-up periods are needed to confirm these results. PMID:27296251

  9. Disposition of 14C-mescaline by rabbit lung.

    PubMed

    Roth, R A; Roth, J A; Gillis, C N

    1977-02-01

    Metabolism of mescaline by several rabbit tissues was examined in vitro. Mescaline-oxidizing activity (micromoles per milligram of protein/15 min) of lung homogenates was 4 times greater than that of either liver or kidney. Brain and plasma each had comparatively little capacity to metabolize mescaline. Mescaline metabolism in vitro was sensitive to inhibition by semicarbazide. Removal of mescaline from the medium perfusing the isolated rabbit lung was explained by intrapulmonary metabolism. Semicarbazide (10(-3) M pargyline. Semicarbazide-treated lungs accumulated more mescaline than did untreated lungs. Mescaline efflux from lung was slower than that of its metabolite. These results indicate that the intact lung removes perfused mescaline and may be important in the disposition of circulating mescaline in vivo.

  10. Semi-automatic lung segmentation of DCE-MRI data sets of 2-year old children after congenital diaphragmatic hernia repair: Initial results.

    PubMed

    Zöllner, Frank G; Daab, Markus; Weidner, Meike; Sommer, Verena; Zahn, Katrin; Schaible, Thomas; Weisser, Gerald; Schoenberg, Stefan O; Neff, K Wolfgang; Schad, Lothar R

    2015-12-01

    In congenital diaphragmatic hernia (CDH), lung hypoplasia and secondary pulmonary hypertension are the major causes of death and severe disability. Based on new therapeutic strategies survival rates could be improved to up to 80%. However, after surgical repair of CDH, long-term follow-up of these pediatric patients is necessary. In this, dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) provides insights into the pulmonary microcirculation and might become a tool within the routine follow-up program of CDH patients. However, whole lung segmentation from DCE-MRI scans is tedious and automated procedures are warranted. Therefore, in this study, an approach to semi-automated lung segmentation is presented. Segmentation of the lung is obtained by calculating the cross correlation and the area under curve between all voxels in the data set and a reference region-of-interest (ROI), here the arterial input function (AIF). By applying an upper and lower threshold to the obtained maps and intersecting these, a final segmentation is reached. This approach was tested on twelve DCE-MRI data sets of 2-year old children after CDH repair. Segmentation accuracy was evaluated by comparing obtained automatic segmentations to manual delineations using the Dice overlap measure. Optimal thresholds for the cross correlation were 0.5/0.95 and 0.1/0.5 for the area under curve, respectively. The ipsilateral (left) lung showed reduced segmentation accuracy compared to the contralateral (right) lung. Average processing time was about 1.4s per data set. Average Dice score was 0.7±0.1 for the whole lung. In conclusion, initial results are promising. By our approach, whole lung segmentation is possible and a rapid evaluation of whole lung perfusion becomes possible. This might allow for a more detailed analysis of lung hypoplasia of children after CDH. PMID:26277730

  11. Semi-automatic lung segmentation of DCE-MRI data sets of 2-year old children after congenital diaphragmatic hernia repair: Initial results.

    PubMed

    Zöllner, Frank G; Daab, Markus; Weidner, Meike; Sommer, Verena; Zahn, Katrin; Schaible, Thomas; Weisser, Gerald; Schoenberg, Stefan O; Neff, K Wolfgang; Schad, Lothar R

    2015-12-01

    In congenital diaphragmatic hernia (CDH), lung hypoplasia and secondary pulmonary hypertension are the major causes of death and severe disability. Based on new therapeutic strategies survival rates could be improved to up to 80%. However, after surgical repair of CDH, long-term follow-up of these pediatric patients is necessary. In this, dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) provides insights into the pulmonary microcirculation and might become a tool within the routine follow-up program of CDH patients. However, whole lung segmentation from DCE-MRI scans is tedious and automated procedures are warranted. Therefore, in this study, an approach to semi-automated lung segmentation is presented. Segmentation of the lung is obtained by calculating the cross correlation and the area under curve between all voxels in the data set and a reference region-of-interest (ROI), here the arterial input function (AIF). By applying an upper and lower threshold to the obtained maps and intersecting these, a final segmentation is reached. This approach was tested on twelve DCE-MRI data sets of 2-year old children after CDH repair. Segmentation accuracy was evaluated by comparing obtained automatic segmentations to manual delineations using the Dice overlap measure. Optimal thresholds for the cross correlation were 0.5/0.95 and 0.1/0.5 for the area under curve, respectively. The ipsilateral (left) lung showed reduced segmentation accuracy compared to the contralateral (right) lung. Average processing time was about 1.4s per data set. Average Dice score was 0.7±0.1 for the whole lung. In conclusion, initial results are promising. By our approach, whole lung segmentation is possible and a rapid evaluation of whole lung perfusion becomes possible. This might allow for a more detailed analysis of lung hypoplasia of children after CDH.

  12. Pattern of brain blood perfusion in tinnitus patients using technetium-99m SPECT imaging

    PubMed Central

    Mahmoudian, Saeid; Farhadi, Mohammad; Gholami, Saeid; Saddadi, Fariba; Karimian, Ali Reza; Mirzaei, Mohammad; Ghoreyshi, Esmaeel; Ahmadizadeh, Majid; Lenarz, Thomas

    2012-01-01

    Background and Purpose: Tinnitus is associated with an increased activity in central auditory system as demonstrated by neuroimaging studies. Brain perfusion scanning using single photon emission computed tomography (SPECT) was done to understand the pattern of brain blood perfusion of tinnitus subjects and find the areas which are mostly abnormal in these patients. Materials and Methods: A number of 122 patients with tinnitus were enrolled to this cross-sectional study. They underwent SPECT and magnetic resonance imaging (MRI) of brain, and the images were fused to find the regions with abnormal perfusion. Results: SPECT scan results were abnormal in 101 patients (83%). Most patients had bilateral abnormal perfusion (N = 65, 53.3%), and most subjects had abnormality in middle-temporal gyrus (N = 83, 68%) and temporoparietal cortex (N = 46, 37.7%). Patients with multifocal involvement had the least mean age than other 2 groups (patients with no abnormality and unifocal abnormality) (P value = 0.045). Conclusions: Brain blood perfusion pattern differs in patient with tinnitus than others. These patients have brain perfusion abnormality, mostly in auditory gyrus (middle temporal) and associative cortex (temporoparietal cortex). Multifocal abnormalities might be due to more cognitive and emotional brain centers involvement due to tinnitus or more stress and anxiety of tinnitus in the young patients. PMID:23267375

  13. Accessory fissures of the lung

    SciTech Connect

    Godwin, D.; Tarver, R.D.

    1985-01-01

    Accessory fissures of the lung are commonly observed in lung specimens, but are often unappreciated or misinterpreted in radiographs and computer tomographic (CT) scans. They usually occur at the boundaries between bronchopulmonary segments. Most common are the inferior accessory fissure, which demarcates the medial basal segment; the superior accessory fissure, which demarcates the superior segment; and the left minor fissure, which demarcates the lingula. This essay will illustrate the findings of the common accessory fissures both on plain radiographs and on CT scans.

  14. Liver Function After Irradiation Based on Computed Tomographic Portal Vein Perfusion Imaging

    SciTech Connect

    Cao Yue Pan, Charlie; Balter, James M.; Platt, Joel F.; Francis, Isaac R.; Knol, James A.; Normolle, Daniel; Ben-Josef, Edgar; Haken, Randall K. ten; Lawrence, Theodore S.

    2008-01-01

    Purpose: To determine whether individual and regional liver sensitivity to radiation could be assessed by measuring liver perfusion during a course of treatment using dynamic contrast-enhanced computed tomography scanning. Methods and Materials: Patients with intrahepatic cancer undergoing conformal radiotherapy underwent dynamic contrast-enhanced computed tomography (to measure perfusion distribution) and an indocyanine extraction study (to measure liver function) before, during, and 1 month after treatment. We hoped to determine whether the residual functioning liver (i.e., those regions showing portal vein perfusion) could be used to predict overall liver function after irradiation. Results: Radiation doses from 45 to 84 Gy resulted in undetectable regional portal vein perfusion 1 month after treatment. The volume of each liver with undetectable portal vein perfusion ranged from 0 to 39% and depended both on the patient's sensitivity and on dose distribution. There was a significant correlation between indocyanine green clearance and the mean of the estimated portal vein perfusion in the functional liver parenchyma (p < 0.001). Conclusion: This study reveals substantial individual variability in the sensitivity of the liver to irradiation. In addition, these findings suggest that hepatic perfusion imaging may be a marker for liver function and has the potential to be a tool for individualizing therapy.

  15. LIVER FUNCTION AFTER IRRADIATION BASED UPON CT PORTAL VEIN PERFUSION IMAGING

    PubMed Central

    Cao, Yue; Pan, Charlie; Balter, James M.; Platt, Joel F.; Francis, Isaac R.; Knol, James A.; Normolle, Daniel; Ben-Josef, Edgar; Ten Haken, Randall K.; Lawrence, Theodore S.

    2009-01-01

    Purpose The role of radiation in the treatment of intrahepatic cancer is limited by the development of radiation-induced liver disease (RILD), which occurs weeks after the course of radiation is completed. We hypothesized that, as the pathophysiology of RILD is veno-occlusive disease, we could assess individual and regional liver sensitivity to radiation by measuring liver perfusion during a course of treatment using dynamic contrast enhanced CT (DCE-CT) scanning. Materials and Methods Patients with intrahepatic cancer undergoing conformal radiotherapy underwent DCE-CT (to measure perfusion distribution) and an indocyanine extraction study (to measure liver function) prior to, during, and one month after treatment. We wished to determine if the residual functioning liver (i.e. those regions showing portal vein perfusion) could be used to predict overall liver function after irradiation. Results Radiation doses from 45 to 84 Gy resulted in undectable regional portal vein perfusion one month after treatment. The volume of each liver with undectable portal vein perfusion ranged from 0% to 39% and depended both on the patient’s sensitivity and dose distribution. There was a significant correlation between indocyanine green clearance and the mean of the estimated portal vein perfusion in the functional liver parenchyma (P < .001). Conclusion This study reveals substantial individual variability in the sensitivity of the liver to irradiation. In addition, these findings suggest that hepatic perfusion imaging may be a marker for liver function, and has the potential to be a tool for individualizing therapy. PMID:17855011

  16. Strategies for Whole Lung Tissue Engineering

    PubMed Central

    Calle, Elizabeth A.; Ghaedi, Mahboobe; Sundaram, Sumati; Sivarapatna, Amogh; Tseng, Michelle K.

    2014-01-01

    Recent work has demonstrated the feasibility of using decellularized lung extracellular matrix scaffolds to support the engineering of functional lung tissue in vitro. Rendered acellular through the use of detergents and other reagents, the scaffolds are mounted in organ-specific bioreactors where cells in the scaffold are provided with nutrients and appropriate mechanical stimuli such as ventilation and perfusion. Though initial studies are encouraging, a great deal remains to be done to advance the field and transition from rodent lungs to whole human tissue engineered lungs. To do so, a variety of hurdles must be overcome. In particular, a reliable source of human-sized scaffolds, as well as a method of terminal sterilization of scaffolds, must be identified. Continued research in lung cell and developmental biology will hopefully help identify the number and types of cells that will be required to regenerate functional lung tissue. Finally, bioreactor designs must be improved in order to provide more precise ventilation stimuli and vascular perfusion in order to avoid injury to or death of the cells cultivated within the scaffold. Ultimately, the success of efforts to engineer a functional lung in vitro will critically depend on the ability to create a fully endothelialized vascular network that provides sufficient barrier function and alveolar-capillary surface area to exchange gas at rates compatible with healthy lung function. PMID:24691527

  17. Contrast-enhanced CT- and MRI-based perfusion assessment for pulmonary diseases: basics and clinical applications

    PubMed Central

    Ohno, Yoshiharu; Koyama, Hisanobu; Lee, Ho Yun; Miura, Sachiko; Yoshikawa, Takeshi; Sugimura, Kazuro

    2016-01-01

    Assessment of regional pulmonary perfusion as well as nodule and tumor perfusions in various pulmonary diseases are currently performed by means of nuclear medicine studies requiring radioactive macroaggregates, dual-energy computed tomography (CT), and dynamic first-pass contrast-enhanced perfusion CT techniques and unenhanced and dynamic first-pass contrast enhanced perfusion magnetic resonance imaging (MRI), as well as time-resolved three-dimensional or four-dimensional contrast-enhanced magnetic resonance angiography (MRA). Perfusion scintigraphy, single-photon emission tomography (SPECT) and SPECT fused with CT have been established as clinically available scintigraphic methods; however, they are limited by perfusion information with poor spatial resolution and other shortcomings. Although positron emission tomography with 15O water can measure absolute pulmonary perfusion, it requires a cyclotron for generation of a tracer with an extremely short half-life (2 min), and can only be performed for academic purposes. Therefore, clinicians are concentrating their efforts on the application of CT-based and MRI-based quantitative and qualitative perfusion assessment to various pulmonary diseases. This review article covers 1) the basics of dual-energy CT and dynamic first-pass contrast-enhanced perfusion CT techniques, 2) the basics of time-resolved contrast-enhanced MRA and dynamic first-pass contrast-enhanced perfusion MRI, and 3) clinical applications of contrast-enhanced CT- and MRI-based perfusion assessment for patients with pulmonary nodule, lung cancer, and pulmonary vascular diseases. We believe that these new techniques can be useful in routine clinical practice for not only thoracic oncology patients, but also patients with different pulmonary vascular diseases. PMID:27523813

  18. Contrast-enhanced CT- and MRI-based perfusion assessment for pulmonary diseases: basics and clinical applications.

    PubMed

    Ohno, Yoshiharu; Koyama, Hisanobu; Lee, Ho Yun; Miura, Sachiko; Yoshikawa, Takeshi; Sugimura, Kazuro

    2016-01-01

    Assessment of regional pulmonary perfusion as well as nodule and tumor perfusions in various pulmonary diseases are currently performed by means of nuclear medicine studies requiring radioactive macroaggregates, dual-energy computed tomography (CT), and dynamic first-pass contrast-enhanced perfusion CT techniques and unenhanced and dynamic first-pass contrast enhanced perfusion magnetic resonance imaging (MRI), as well as time-resolved three-dimensional or four-dimensional contrast-enhanced magnetic resonance angiography (MRA). Perfusion scintigraphy, single-photon emission tomography (SPECT) and SPECT fused with CT have been established as clinically available scintigraphic methods; however, they are limited by perfusion information with poor spatial resolution and other shortcomings. Although positron emission tomography with 15O water can measure absolute pulmonary perfusion, it requires a cyclotron for generation of a tracer with an extremely short half-life (2 min), and can only be performed for academic purposes. Therefore, clinicians are concentrating their efforts on the application of CT-based and MRI-based quantitative and qualitative perfusion assessment to various pulmonary diseases. This review article covers 1) the basics of dual-energy CT and dynamic first-pass contrast-enhanced perfusion CT techniques, 2) the basics of time-resolved contrast-enhanced MRA and dynamic first-pass contrast-enhanced perfusion MRI, and 3) clinical applications of contrast-enhanced CT- and MRI-based perfusion assessment for patients with pulmonary nodule, lung cancer, and pulmonary vascular diseases. We believe that these new techniques can be useful in routine clinical practice for not only thoracic oncology patients, but also patients with different pulmonary vascular diseases.

  19. Contrast-enhanced CT- and MRI-based perfusion assessment for pulmonary diseases: basics and clinical applications.

    PubMed

    Ohno, Yoshiharu; Koyama, Hisanobu; Lee, Ho Yun; Miura, Sachiko; Yoshikawa, Takeshi; Sugimura, Kazuro

    2016-01-01

    Assessment of regional pulmonary perfusion as well as nodule and tumor perfusions in various pulmonary diseases are currently performed by means of nuclear medicine studies requiring radioactive macroaggregates, dual-energy computed tomography (CT), and dynamic first-pass contrast-enhanced perfusion CT techniques and unenhanced and dynamic first-pass contrast enhanced perfusion magnetic resonance imaging (MRI), as well as time-resolved three-dimensional or four-dimensional contrast-enhanced magnetic resonance angiography (MRA). Perfusion scintigraphy, single-photon emission tomography (SPECT) and SPECT fused with CT have been established as clinically available scintigraphic methods; however, they are limited by perfusion information with poor spatial resolution and other shortcomings. Although positron emission tomography with 15O water can measure absolute pulmonary perfusion, it requires a cyclotron for generation of a tracer with an extremely short half-life (2 min), and can only be performed for academic purposes. Therefore, clinicians are concentrating their efforts on the application of CT-based and MRI-based quantitative and qualitative perfusion assessment to various pulmonary diseases. This review article covers 1) the basics of dual-energy CT and dynamic first-pass contrast-enhanced perfusion CT techniques, 2) the basics of time-resolved contrast-enhanced MRA and dynamic first-pass contrast-enhanced perfusion MRI, and 3) clinical applications of contrast-enhanced CT- and MRI-based perfusion assessment for patients with pulmonary nodule, lung cancer, and pulmonary vascular diseases. We believe that these new techniques can be useful in routine clinical practice for not only thoracic oncology patients, but also patients with different pulmonary vascular diseases. PMID:27523813

  20. Quantitative assessment of angiogenesis, perfused blood vessels and endothelial tip cells in the postnatal mouse brain.

    PubMed

    Wälchli, Thomas; Mateos, José María; Weinman, Oliver; Babic, Daniela; Regli, Luca; Hoerstrup, Simon P; Gerhardt, Holger; Schwab, Martin E; Vogel, Johannes

    2015-01-01

    During development and in various diseases of the CNS, new blood vessel formation starts with endothelial tip cell selection and vascular sprout migration, followed by the establishment of functional, perfused blood vessels. Here we describe a method that allows the assessment of these distinct angiogenic steps together with antibody-based protein detection in the postnatal mouse brain. Intravascular and perivascular markers such as Evans blue (EB), isolectin B4 (IB4) or laminin (LN) are used alongside simultaneous immunofluorescence on the same sections. By using confocal laser-scanning microscopy and stereological methods for analysis, detailed quantification of the 3D postnatal brain vasculature for perfused and nonperfused vessels (e.g., vascular volume fraction, vessel length and number, number of branch points and perfusion status of the newly formed vessels) and characterization of sprouting activity (e.g., endothelial tip cell density, filopodia number) can be obtained. The entire protocol, from mouse perfusion to vessel analysis, takes ∼10 d.

  1. Impaired microcirculatory perfusion in a rat model of cardiopulmonary bypass: the role of hemodilution.

    PubMed

    Koning, Nick J; de Lange, Fellery; Vonk, Alexander B A; Ahmed, Yunus; van den Brom, Charissa E; Bogaards, Sylvia; van Meurs, Matijs; Jongman, Rianne M; Schalkwijk, Casper G; Begieneman, Mark P V; Niessen, Hans W; Baufreton, Christophe; Boer, Christa

    2016-03-01

    Although hemodilution is attributed as the main cause of microcirculatory impairment during cardiopulmonary bypass (CPB), this relationship has never been investigated. We investigated the distinct effects of hemodilution with or without CPB on microvascular perfusion and subsequent renal tissue injury in a rat model. Male Wistar rats (375-425 g) were anesthetized, prepared for cremaster muscle intravital microscopy, and subjected to CPB (n = 9), hemodilution alone (n = 9), or a sham procedure (n = 6). Microcirculatory recordings were performed at multiple time points and analyzed for perfusion characteristics. Kidney and lung tissue were investigated for mRNA expression for genes regulating inflammation and endothelial adhesion molecule expression. Renal injury was assessed with immunohistochemistry. Hematocrit levels dropped to 0.24 ± 0.03 l/l and 0.22 ± 0.02 l/l after onset of hemodilution with or without CPB. Microcirculatory perfusion remained unaltered in sham rats. Hemodilution alone induced a 13% decrease in perfused capillaries, after which recovery was observed. Onset of CPB reduced the perfused capillaries by 40% (9.2 ± 0.9 to 5.5 ± 1.5 perfused capillaries per microscope field; P < 0.001), and this reduction persisted throughout the experiment. Endothelial and inflammatory activation and renal histological injury were increased after CPB compared with hemodilution or sham procedure. Hemodilution leads to minor and transient disturbances in microcirculatory perfusion, which cannot fully explain impaired microcirculation following cardiopulmonary bypass. CPB led to increased renal injury and endothelial adhesion molecule expression in the kidney and lung compared with hemodilution. Our findings suggest that microcirculatory impairment during CPB may play a role in the development of kidney injury.

  2. MRI Scans

    MedlinePlus

    Magnetic resonance imaging (MRI) uses a large magnet and radio waves to look at organs and structures inside your body. Health care professionals use MRI scans to diagnose a variety of conditions, from torn ...

  3. WBC scan

    MedlinePlus

    Leukocyte scan ... will be taken from one of your veins. White blood cells are separated from the rest of the blood ... 111. These cells are considered tagged. The tagged white blood cells are injected back into your body through a ...

  4. Quantification of myocardial perfusion based on signal intensity of flow sensitized MRI

    NASA Astrophysics Data System (ADS)

    Abeykoon, Sumeda B.

    The quantitative assessment of perfusion is important for early recognition of a variety of heart diseases, determination of disease severity and their cure. In conventional approach of measuring cardiac perfusion by arterial spin labeling, the relative difference in the apparent T1 relaxation times in response to selective and non-selective inversion of blood entering the region of interest is related to perfusion via a two-compartment tissue model. But accurate determination of T1 in small animal hearts is difficult and prone to errors due to long scan times. The purpose of this study is to develop a fast, robust and simple method to quantitatively assess myocardial perfusion using arterial spin labeling. The proposed method is based on signal intensities (SI) of inversion recovery slice-select, non-select and steady-state images. Especially in this method data are acquired at a single inversion time and at short repetition times. This study began by investigating the accuracy of assessment of perfusion using a two compartment system. First, determination of perfusion by T1 and SI were implemented to a simple, two-compartment phantom model. Mathematical model developed for full spin exchange models (in-vivo experiments) by solving a modified Bloch equation was modified to develop mathematical models (T1 and SI) for a phantom (zero spin exchange). The phantom result at different flow rates shows remarkable evidence of accuracy of the two-compartment model and SI, T1 methods: the SI method has less propagation error and less scan time. Next, twelve healthy C57BL/6 mice were scanned for quantitative perfusion assessment and three of them were repeatedly scanned at three different time points for a reproducibility test. The myocardial perfusion of healthy mice obtained by the SI-method, 5.7+/-1.6 ml/g/min, was similar (p=0.38) to that obtained by the conventional T1 method, 5.6+/- 2.3 ml/g/min. The reproducibility of the SI method shows acceptable results: the

  5. Artificial tissues in perfusion culture.

    PubMed

    Sittinger, M; Schultz, O; Keyszer, G; Minuth, W W; Burmester, G R

    1997-01-01

    In the stagnant environment of traditional culture dishes it is difficult to generate long term experiments or artificial tissues from human cells. For this reason a perfusion culture system with a stable supply of nutrients was developed. Human chondrocytes were seeded three-dimensionally in resorbable polymer fleeces. The cell-polymer tissues were then mounted in newly developed containers (W.W. Minuth et al, Biotechniques, 1996) and continuously perfused by fresh medium for 40 days. Samples from the effluate were analyzed daily, and the pH of the medium and glucose concentration remained stable during this period. The lactid acid concentration increased from 0.17 mg/ml to 0.35 mg/ml, which was influenced by the degradation of the resorbable polymer fibers used as three dimensional support material for the cells. This perfusion system proved to be reliable especially in long term cultures. Any components in the culture medium of the cells could be monitored without disturbances as caused by manual medium replacement. These results suggest the described perfusion culture system to be a valuable and convenient tool for many applications in tissue engineering, especially in the generation of artificial connective tissue.

  6. Developing a tissue perfusion sensor.

    PubMed

    Harvey, S L R; Parker, K H; O'Hare, D

    2007-01-01

    The development of a electrochemical tissue perfusion sensor is presented. The sensor is a platinum/platinum ring-disc microelectrode that relies on the principle of collector-generator to monitor mass transport within its vicinity. Tissue perfusion is a mass transport mechanism that describes the movement of respiratory gases, nutrients and metabolites in tissue. The sensor's capability of detecting perfusion at the cellular level in a continuous fashion is unique. This sensor will provide insight into the way nutrients and metabolites are transported in tissue especially in cases were perfusion is low such as in wounds or ischemic tissue. We present experimental work for the development and testing of the sensors in vitro. Experimental flow recordings in free steam solutions as well as the flow through tissue-like media are shown. Tests on post operative human tissue are also presented. The sensor's feature such as the continuous recoding capacities, spatial resolution and the measurement range from ml/min to microl/min are highlighted. PMID:18002549

  7. Detectability of perfusion defect in five-dimensional gated-dynamic cardiac SPECT images

    PubMed Central

    Niu, Xiaofeng; Yang, Yongyi; King, Michael A.; Wernick, Miles N.

    2010-01-01

    Purpose: In previous work, the authors developed and demonstrated the concept of an image reconstruction procedure aimed to unify gated and dynamic nuclear cardiac imaging, which the authors have termed five-dimensional (5D) SPECT. Gated imaging permits the clinician to evaluate wall motion and, through the use of stress and rest scans, allows perfusion defects to be observed. Dynamic imaging depicts kinetics in the myocardium, which can be used to evaluate perfusion, but traditional dynamic images are motionless and do not depict wall motion. In this article, the authors investigate the degree to which perfusion defects can be detected from the dynamic information conveyed by 5D images, a problem that is particularly challenging in the absence of multiple fast camera rotations. Methods: The authors first demonstrate the usefulness of dynamic reconstructed images for perfusion detection by using linear discriminant analyses (Fisher linear discriminant analysis and principal component analysis) and a numerical channelized Hotelling observer. The authors then derive three types of discriminant metrics for characterizing the temporal kinetic information in reconstructed dynamic images for differentiating perfusion defects from normal cardiac perfusion, which are the Fisher linear discriminant map, temporal derivative map, and kinetic parametric images. Results: Results are based on the NURBS-based cardiac-torso phantom with simulation of Tc99m-teboroxime as the imaging agent. The derived metric maps and quantitative contrast-to-noise ratio results demonstrate that the reconstructed dynamic images could yield higher detectability of the perfusion defect than conventional gated reconstruction while providing wall motion information simultaneously. Conclusions: The proposed metrics can be used to produce new types of visualizations, showing wall motion and perfusion information, that may potentially be useful for clinical evaluation. Since 5D imaging permits wall motion

  8. Mesenteric and splenic contributions to portal venous CT perfusion in hepatic diffuse disease

    PubMed Central

    Sun, Hongzan; Lu, Zaiming; Liang, Hongyuan; Xin, Jun; Gao, Yuying; Guo, Qiyong

    2014-01-01

    Aim: To investigate the changes and contributions of superior mesenteric venous perfusion (SMVP) and splenic venous perfusion (SpVP) to portal venous CT perfusion in canine model of hepatic diffuse disease. Materials and methods: By selective catheterization in superior mesenteric and splenic arteries respectively after CT perfusion scanning, SMVP and SpVP became available. Sixteen dogs were adopted and induced by carbon tetrachloride after data under normal conditions were collected. After 3, 6, 9 and 12 months from carbon tetrachloride intervention, liver biopsies by puncture or operation were performed after CT perfusion scanning. SMVP and SpVP under different pathologic conditions were compared and analyzed. Results: Three stages of hepatic diffuse lesions were defined according to pathologic changes, namely hepatitis, hepatic fibrosis, and cirrhosis. The number of dogs which survived from each stage was: 16 from normal, 12 from hepatitis, 10 from hepatic fibrosis and 4 from cirrhosis. During this progressive period, SpVP ml/(min·100 ml) declined slightly, but there were no significant differences between different stages (P > 0.05). SMVP ml/(min·100 ml) in stage of normal (64.1 ± 8.1) and hepatic fibrosis (44.4 ± 4.5), normal and cirrhosis (42.6 ± 5.4), hepatitis (61.3 ± 6.4) and hepatic fibrosis, hepatitis and cirrhosis was significantly different, but there was no significant difference of SMVP between normal and hepatitis (P = 0.326) or hepatic fibrosis and cirrhosis (P = 0.668). Conclusions: With our evidence of interventional CT perfusion, it is mesenteric, not splenic, perfusion that might coincide with hepatic portal venous perfusion during the progressive period of hepatic diffuse disease. PMID:25550855

  9. Lung disease

    MedlinePlus

    ... the lungs to take in oxygen and release carbon dioxide. People with this type of lung disorder often ... the lungs to take up oxygen and release carbon dioxide. These diseases may also affect heart function. An ...

  10. Collapsed Lung

    MedlinePlus

    A collapsed lung happens when air enters the pleural space, the area between the lung and the chest wall. If it is a ... is called pneumothorax. If only part of the lung is affected, it is called atelectasis. Causes of ...

  11. Optical Coherence Tomography Angiography of Optic Disc Perfusion in Glaucoma

    PubMed Central

    Jia, Yali; Wei, Eric; Wang, Xiaogang; Zhang, Xinbo; Morrison, John C.; Parikh, Mansi; Lombardi, Lori H.; Gattey, Devin M.; Armour, Rebecca L.; Edmunds, Beth; Kraus, Martin F.; Fujimoto, James G.; Huang, David

    2014-01-01

    Purpose To compare optic disc perfusion between normal and glaucoma subjects using optical coherence tomography (OCT) angiography and detect optic disc perfusion changes in glaucoma. Design Observational, cross-sectional study. Participants Twenty-four normal subjects and 11 glaucoma patients were included. Methods One eye of each subject was scanned by a high-speed 1050 nm wavelength swept-source OCT instrument. The split-spectrum amplitude-decorrelation angiography algorithm (SSADA) was used to compute three-dimensional optic disc angiography. A disc flow index was computed from four registered scans. Confocal scanning laser ophthalmoscopy (cSLO) was used to measure disc rim area, and stereo photography was used to evaluate cup/disc ratios. Wide field OCT scans over the discs were used to measure retinal nerve fiber layer (NFL) thickness. Main Outcome Measurements Variability was assessed by coefficient of variation (CV). Diagnostic accuracy was assessed by sensitivity and specificity. Comparisons between glaucoma and normal groups were analyzed by Wilcoxon rank-sum test. Correlations between disc flow index, structural assessments, and visual field (VF) parameters were assessed by linear regression. Results In normal discs, a dense microvascular network was visible on OCT angiography. This network was visibly attenuated in glaucoma subjects. The intra-visit repeatability, inter-visit reproducibility, and normal population variability of the optic disc flow index were 1.2%, 4.2%, and 5.0% CV respectively. The disc flow index was reduced by 25% in the glaucoma group (p = 0.003). Sensitivity and specificity were both 100% using an optimized cutoff. The flow index was highly correlated with VF pattern standard deviation (R2 = 0.752, p = 0.001). These correlations were significant even after accounting for age, cup/disc area ratio, NFL, and rim area. Conclusions OCT angiography, generated by the new SSADA algorithm, repeatably measures optic disc perfusion. OCT

  12. Does machine perfusion decrease ischemia reperfusion injury?

    PubMed

    Bon, D; Delpech, P-O; Chatauret, N; Hauet, T; Badet, L; Barrou, B

    2014-06-01

    In 1990's, use of machine perfusion for organ preservation has been abandoned because of improvement of preservation solutions, efficient without perfusion, easy to use and cheaper. Since the last 15 years, a renewed interest for machine perfusion emerged based on studies performed on preclinical model and seems to make consensus in case of expanded criteria donors or deceased after cardiac death donations. We present relevant studies highlighted the efficiency of preservation with hypothermic machine perfusion compared to static cold storage. Machines for organ preservation being in constant evolution, we also summarized recent developments included direct oxygenation of the perfusat. Machine perfusion technology also enables organ reconditioning during the last hours of preservation through a short period of perfusion on hypothermia, subnormothermia or normothermia. We present significant or low advantages for machine perfusion against ischemia reperfusion injuries regarding at least one primary parameter: risk of DFG, organ function or graft survival.

  13. Sodium efflux from perfused giant algal cells.

    PubMed

    Clint, G M; Macrobbie, E A

    1987-06-01

    Internodal cells of the giant alga Chara corallina were perfused internally to replace the native cytoplasm, tonoplast and vacuole with artificial cytoplasm. Sodium efflux from perfused cells, measured by including (22)Na in the perfusion media, was increased by increasing the internal sodium concentration and by decreasing the external pH, and was inhibited by external application of the renal diuretic amiloride. The sodium efflux was markedly ATP-dependent, with a 50-fold decrease in efflux observed after perfusion with media lacking ATP. Efflux in the presence of ATP was reduced by 33% by inclusion of 10 μM N,N'-dicyclohexylcarbodiimide in the perfusion medium. The membrane potential of the perfused cells approximated that of intact cells from the same culture. It is suggested that sodium efflux in perfused Chara cells proceeds via a secondary antiporter with protons, regulated by ATP in a catalytic role and with the proton motive force acting as the energy source.

  14. Cerebral abnormalities in cocaine abusers: Demonstration by SPECT perfusion brain scintigraphy. Work in progress

    SciTech Connect

    Tumeh, S.S.; Nagel, J.S.; English, R.J.; Moore, M.; Holman, B.L. )

    1990-09-01

    Single photon emission computed tomography (SPECT) perfusion brain scans with iodine-123 isopropyl iodoamphetamine (IMP) were obtained in 12 subjects who acknowledged using cocaine on a sporadic to a daily basis. The route of cocaine administration varied from nasal to intravenous. Concurrent abuse of other drugs was also reported. None of the patients were positive for human immunodeficiency virus. Brain scans demonstrated focal defects in 11 subjects, including seven who were asymptomatic, and no abnormality in one. Among the findings were scattered focal cortical deficits, which were seen in several patients and which ranged in severity from small and few to multiple and large, with a special predilection for the frontal and temporal lobes. No perfusion deficits were seen on I-123 SPECT images in five healthy volunteers. Focal alterations in cerebral perfusion are seen commonly in asymptomatic drug users, and these focal deficits are readily depicted by I-123 IMP SPECT.

  15. Pulmonary and bronchial circulations: contributions to heat and water exchange in isolated lungs.

    PubMed

    Serikov, V B; Fleming, N W

    2001-11-01

    The relative contribution of the pulmonary and bronchial circulatory systems to heat and water exchange in normal lungs was evaluated in 20 isolated, in situ perfused dog lungs and in four patients undergoing elective cardiopulmonary bypass. In isolated dog lungs, if the pulmonary artery was perfused at a nominal flow rate (0.5 l/min), bronchial artery perfusion (up to 70 ml/min) did not significantly affect the expired gas temperature. When the lungs were not perfused through either system, 8 min of ventilation with cool, dry gas decreased the temperature of the expired gas by 6.2 +/- 1.4 degrees C. Selective perfusion of bronchial arteries at 68 +/- 10 mmHg resulted in a mean flow rate of 28 +/- 16 ml/min and increased the average temperature of the expired gas by 0.6 degrees C. An increase in the rate of bronchial arterial perfusion to 55 +/- 14 ml/min increased the average temperature of the expired gas by 1.3 degrees C. The time constant for equilibration of tritiated water between the perfusate and the lung parenchyma was 130 +/- 33 min for pulmonary arterial perfusion and 35 +/- 13 min for combined bronchial and pulmonary perfusion, which indicated that filtration of water from high-pressure bronchial vessels facilitated water exchange in the lung interstitium. The rate of tracer equilibration was similar between the perfusate and gas in both variants of perfusion, but the ratios of tracer gas to perfusate were different (0.42 +/- 0.06 for pulmonary, 0.98 +/- 0.07 for combined), which indicates that bronchial vessels contribute mainly to the hydration of the bronchial mucosa. In humans, the bronchial blood flow was capable of maintaining heat supply after the initiation of cardiopulmonary bypass. Before bypass, when both pulmonary and bronchial blood flow were present, the mean time constant of the temperature decay after a switch to ventilation with cool, dry gas was 35 +/- 12 s. The average temperature difference between the blood and expired gas was 2

  16. Organ perfusion during voluntary pulmonary hyperinflation; a magnetic resonance imaging study.

    PubMed

    Kyhl, Kasper; Drvis, Ivan; Barak, Otto; Mijacika, Tanja; Engstrøm, Thomas; Secher, Niels H; Dujic, Zeljko; Buca, Ante; Madsen, Per Lav

    2016-02-01

    Pulmonary hyperinflation is used by competitive breath-hold divers and is accomplished by glossopharyngeal insufflation (GPI), which is known to compress the heart and pulmonary vessels, increasing sympathetic activity and lowering cardiac output (CO) without known consequence for organ perfusion. Myocardial, pulmonary, skeletal muscle, kidney, and liver perfusion were evaluated by magnetic resonance imaging in 10 elite breath-hold divers at rest and during moderate GPI. Cardiac chamber volumes, stroke volume, and thus CO were determined from cardiac short-axis cine images. Organ volumes were assessed from gradient echo sequences, and organ perfusion was evaluated from first-pass images after gadolinium injection. During GPI, lung volume increased by 5.2 ± 1.5 liters (mean ± SD; P < 0.001), while spleen and liver volume decreased by 46 ± 39 and 210 ± 160 ml, respectively (P < 0.05), and inferior caval vein diameter by 4 ± 3 mm (P < 0.05). Heart rate tended to increase (67 ± 10 to 86 ± 20 beats/min; P = 0.052) as right and left ventricular volumes were reduced (P < 0.05). Stroke volume (107 ± 21 to 53 ± 15 ml) and CO (7.2 ± 1.6 to 4.2 ± 0.8 l/min) decreased as assessed after 1 min of GPI (P < 0.01). Left ventricular myocardial perfusion maximum upslope and its perfusion index decreased by 1.52 ± 0.15 s(-1) (P < 0.001) and 0.02 ± 0.01 s(-1) (P < 0.05), respectively, without transmural differences. Pulmonary tissue, spleen, kidney, and pectoral-muscle perfusion also decreased (P < 0.05), and yet liver perfusion was maintained. Thus, during pulmonary hyperinflation by GPI, CO and organ perfusion, including the myocardium, as well as perfusion of skeletal muscles, are reduced, and yet perfusion of the liver is maintained. Liver perfusion seems to be prioritized when CO decreases during GPI. PMID:26589331

  17. Using the inherent chemistry of the endothelin-1 peptide to develop a rapid assay for pre-transplant donor lung assessment.

    PubMed

    Sage, Andrew T; Bai, Xiaohui; Cypel, Marcelo; Liu, Mingyao; Keshavjee, Shaf; Kelley, Shana O

    2015-12-21

    Endothelin-1 is a potent vasoconstrictive peptide that plays an important role in ex vivo lung perfusion. ET-1 expression levels are predictive of lung transplant outcomes and represent a valuable monitoring tool for surgeons; however, traditional techniques that measure [ET-1] are not suitable for the transplant setting. Herein, we demonstrate a new assay that rapidly measures ET-1 peptide levels in lung perfusate. PMID:26548776

  18. Using the inherent chemistry of the endothelin-1 peptide to develop a rapid assay for pre-transplant donor lung assessment.

    PubMed

    Sage, Andrew T; Bai, Xiaohui; Cypel, Marcelo; Liu, Mingyao; Keshavjee, Shaf; Kelley, Shana O

    2015-12-21

    Endothelin-1 is a potent vasoconstrictive peptide that plays an important role in ex vivo lung perfusion. ET-1 expression levels are predictive of lung transplant outcomes and represent a valuable monitoring tool for surgeons; however, traditional techniques that measure [ET-1] are not suitable for the transplant setting. Herein, we demonstrate a new assay that rapidly measures ET-1 peptide levels in lung perfusate.

  19. [Vasoconstriction is required for edema of contralateral lung after reperfusion injury of one lung].

    PubMed

    Pezzulo, Alejandro; Castro, Ignacio; Trejo, Humberto; Urich, Daniela; Caraballo, Juan; Gutiérrez, Jeydith; Cano, Camilo; Sánchez de León, Roberto

    2010-03-01

    Ischemia-reperfusion (IR) lung injury is a significant cause of morbidity and mortality in certain clinical scenarios that include transplantation, thromboendarterectomy and reexpansion injury of the lung. Edema of the contralateral lung after IR injury of one lung has been reported and this study was aimed to clarify the pathophysiology of this phenomenon. One-lung ischemia/hypoxia followed by reperfusion with either blood or an acellular plasma substitute was achieved in an isolated rabbit lung model by hilum clamping. After reperfusion, we studied the isolated effects of vasoconstriction and inflammation on contralateral lung injury by using papaverine or hydrocortisone as vasodilator and anti-inflammatory, respectively. We observed that IR of one lung induces edema of the contralateral lung. Absence of leukocytes and platelets in the perfusate or use of hydrocortisone completely inhibits IR injury. Moreover, papaverine suppresses edema of the contralateral, but not that of the reperfused lung. We concluded that IR of one lung produces edema in the contralateral lung that requires vasoconstriction of the latter. PMID:20815156

  20. Intestinal perfusion monitoring using photoplethysmography

    NASA Astrophysics Data System (ADS)

    Akl, Tony J.; Wilson, Mark A.; Ericson, M. Nance; Coté, Gerard L.

    2013-08-01

    In abdominal trauma patients, monitoring intestinal perfusion and oxygen consumption is essential during the resuscitation period. Photoplethysmography is an optical technique potentially capable of monitoring these changes in real time to provide the medical staff with a timely and quantitative measure of the adequacy of resuscitation. The challenges for using optical techniques in monitoring hemodynamics in intestinal tissue are discussed, and the solutions to these challenges are presented using a combination of Monte Carlo modeling and theoretical analysis of light propagation in tissue. In particular, it is shown that by using visible wavelengths (i.e., 470 and 525 nm), the perfusion signal is enhanced and the background contribution is decreased compared with using traditional near-infrared wavelengths leading to an order of magnitude enhancement in the signal-to-background ratio. It was further shown that, using the visible wavelengths, similar sensitivity to oxygenation changes could be obtained (over 50% compared with that of near-infrared wavelengths). This is mainly due to the increased contrast between tissue and blood in that spectral region and the confinement of the photons to the thickness of the small intestine. Moreover, the modeling results show that the source to detector separation should be limited to roughly 6 mm while using traditional near-infrared light, with a few centimeters source to detector separation leads to poor signal-to-background ratio. Finally, a visible wavelength system is tested in an in vivo porcine study, and the possibility of monitoring intestinal perfusion changes is showed.

  1. Reducing CT dose in myocardial perfusion SPECT/CT.

    PubMed

    O'Shaughnessy, Emma; Dixon, Kat L

    2015-11-01

    The aim of this study was to reduce the radiation dose arising from computed tomography (CT) attenuation correction to single photon emission computed tomography myocardial perfusion imaging studies without adversely affecting its accuracy. Using the Perspex CTDI phantom with the Xi detector to measure dose, CT scans were acquired using the Siemens Symbia T over the full range of CT settings available. Using the default setting 'AECmean', the measured dose at the centre of the phantom was 1.68 mGy and the breast dose from the scout view was 0.30 mGy. The lowest dose was achieved using the dose modulation setting in which the doses were reduced to 1.21 mGy and undetectable (<0.01 mGy), respectively. To observe the effect of changing these settings, 30 patients received a stress scan with default CT settings and a rest scan utilizing single photon emission computed tomography-guided CT and the dose modulation CT settings. Results showed a mean effective dose reduction of 23.6%. The dose reduction was greatest for larger patients, with the largest dose reduction for one patient being 72%. There was no apparent difference in attenuation correction between the two sets of resultant images. These new lower-dose settings are now applied to all clinical myocardial perfusion imaging studies. PMID:26302461

  2. ASFNR recommendations for clinical performance of MR dynamic susceptibility contrast perfusion imaging of the brain.

    PubMed

    Welker, K; Boxerman, J; Kalnin, A; Kaufmann, T; Shiroishi, M; Wintermark, M

    2015-06-01

    MR perfusion imaging is becoming an increasingly common means of evaluating a variety of cerebral pathologies, including tumors and ischemia. In particular, there has been great interest in the use of MR perfusion imaging for both assessing brain tumor grade and for monitoring for tumor recurrence in previously treated patients. Of the various techniques devised for evaluating cerebral perfusion imaging, the dynamic susceptibility contrast method has been employed most widely among clinical MR imaging practitioners. However, when implementing DSC MR perfusion imaging in a contemporary radiology practice, a neuroradiologist is confronted with a large number of decisions. These include choices surrounding appropriate patient selection, scan-acquisition parameters, data-postprocessing methods, image interpretation, and reporting. Throughout the imaging literature, there is conflicting advice on these issues. In an effort to provide guidance to neuroradiologists struggling to implement DSC perfusion imaging in their MR imaging practice, the Clinical Practice Committee of the American Society of Functional Neuroradiology has provided the following recommendations. This guidance is based on review of the literature coupled with the practice experience of the authors. While the ASFNR acknowledges that alternate means of carrying out DSC perfusion imaging may yield clinically acceptable results, the following recommendations should provide a framework for achieving routine success in this complicated-but-rewarding aspect of neuroradiology MR imaging practice.

  3. Retrospective Analysis of Lung Transplant Recipients Found to Have Unexpected Lung Cancer in Explanted Lungs.

    PubMed

    Nakajima, Takahiro; Cypel, Marcelo; de Perrot, Marc; Pierre, Andrew; Waddell, Tom; Singer, Lianne; Roberts, Heidi; Keshavjee, Shaf; Yasufuku, Kazuhiro

    2015-01-01

    Unexpected lung cancer is sometimes found in explanted lungs. The objective of this study was to review these patients and their outcomes to better understand and optimize management protocols for lung transplant candidates with pulmonary nodules. Retrospective analysis of pretransplant imaging and clinicopathologic characteristics of patients who were found to have lung cancer in their explanted lungs was performed. From January 2003 to December 2012, 13 of 853 lung transplant recipients were found to have unexpected lung cancer in their explanted lung (1.52%). Of them, 9 cases were for interstitial lung disease (2.8%; 9/321 recipients) and 4 cases were for chronic obstructive pulmonary disease (1.57%; 4/255 recipients). The median period between computed tomographic scan and lung transplantation was 2.40 months (range: 0.5-19.2). On computed tomographic scan, only 3 cases were shown to possibly have a neoplasm by the radiologist. The staging of these lung cancers was as follows: 3 cases of IA, 1 case of IB, 5 cases of IIA, 1 case of IIIA, and 3 cases of IV. Of 13 cases, 9 died owing to cancer progression. On the contrary, only 1 stage I case with small cell lung cancer showed cancer recurrence. The median survival time was 339 days, and the 3-year survival rate was 11.0%. In conclusion, most of the patients with unexpected lung cancer showed poor prognosis except for the early-stage disease. The establishment of proper protocol for management of such nodules is important to improve the management of candidates who are found to have pulmonary nodules on imaging. PMID:26074103

  4. Ultrasound perfusion signal processing for tumor detection

    NASA Astrophysics Data System (ADS)

    Kim, MinWoo; Abbey, Craig K.; Insana, Michael F.

    2016-04-01

    Enhanced blood perfusion in a tissue mass is an indication of neo-vascularity and a sign of a potential malignancy. Ultrasonic pulsed-Doppler imaging is a preferred modality for noninvasive monitoring of blood flow. However, the weak blood echoes and disorganized slow flow make it difficult to detect perfusion using standard methods without the expense and risk of contrast enhancement. Our research measures the efficiency of conventional power-Doppler (PD) methods at discriminating flow states by comparing measurement performance to that of an ideal discriminator. ROC analysis applied to the experimental results shows that power Doppler methods are just 30-50 % efficient at perfusion flows less than 1ml/min, suggesting an opportunity to improve perfusion assessment through signal processing. A new perfusion estimator is proposed by extending the statistical discriminator approach. We show that 2-D perfusion color imaging may be enhanced using this approach.

  5. Repeatability and reproducibility of optic nerve head perfusion measurements using optical coherence tomography angiography

    NASA Astrophysics Data System (ADS)

    Chen, Chieh-Li; Bojikian, Karine D.; Xin, Chen; Wen, Joanne C.; Gupta, Divakar; Zhang, Qinqin; Mudumbai, Raghu C.; Johnstone, Murray A.; Chen, Philip P.; Wang, Ruikang K.

    2016-06-01

    Optical coherence tomography angiography (OCTA) has increasingly become a clinically useful technique in ophthalmic imaging. We evaluate the repeatability and reproducibility of blood perfusion in the optic nerve head (ONH) measured using optical microangiography (OMAG)-based OCTA. Ten eyes from 10 healthy volunteers are recruited and scanned three times with a 68-kHz Cirrus HD-OCT 5000-based OMAG prototype system (Carl Zeiss Meditec Inc., Dublin, California) centered at the ONH involving two separate visits within six weeks. Vascular images are generated with OMAG processing by detecting the differences in OCT signals between consecutive B-scans acquired at the same retina location. ONH perfusion is quantified as flux, vessel area density, and normalized flux within the ONH for the prelaminar, lamina cribrosa, and the full ONH. Coefficient of variation (CV) and intraclass correlation coefficient (ICC) are used to evaluate intravisit and intervisit repeatability, and interobserver reproducibility. ONH perfusion measurements show high repeatability [CV≤3.7% (intravisit) and ≤5.2% (intervisit)] and interobserver reproducibility (ICC≤0.966) in all three layers by three metrics. OCTA provides a noninvasive method to visualize and quantify ONH perfusion in human eyes with excellent repeatability and reproducibility, which may add additional insight into ONH perfusion in clinical practice.

  6. Perineal scanning.

    PubMed

    Jeanty, P; d'Alton, M; Romero, R; Hobbins, J C

    1986-10-01

    Although various techniques have been described to aid in the ultrasound diagnosis of placenta previa and incompetent cervix, these maneuvers depend on the precise identification of the internal cervical os, a feat which is notoriously difficult to accomplish consistently. In an attempt to get a closer view of the cervix we tried another approach. This simple technique of perineal scanning has the potential to help considerably with these problems. PMID:3530265

  7. QUANTITATIVE CT ANALYSIS, AIRFLOW OBSTRUCTION AND LUNG CANCER IN THE PITTSBURGH LUNG SCREENING STUDY

    PubMed Central

    Wilson, David O; Leader, Joseph K; Fuhrman, Carl R; Reilly, John J; Sciurba, Frank C.; Weissfeld, Joel L

    2011-01-01

    Background To study the relationship between emphysema, airflow obstruction and lung cancer in a high risk population we performed quantitative analysis of screening computed tomography (CT) scans. Methods Subjects completed questionnaires, spirometry and low-dose helical chest CT. Analyses compared cases and controls according to automated quantitative analysis of lung parenchyma and airways measures. Results Our case-control study of 117 matched pairs of lung cancer cases and controls did not reveal any airway or lung parenchymal findings on quantitative analysis of screening CT scans that were associated with increased lung cancer risk. Airway measures including wall area %, lumen perimeter, lumen area and average wall HU, and parenchymal measures including lung fraction < −910 Hounsfield Units (HU), were not statistically different between cases and controls. Conclusions The relationship between visual assessment of emphysema and increased lung cancer risk could not be verified by quantitative analysis of low-dose screening CT scans in a high risk tobacco exposed population. PMID:21610523

  8. Optical imaging of tissue mitochondrial redox state in intact rat lungs in two models of pulmonary oxidative stress.

    PubMed

    Sepehr, Reyhaneh; Staniszewski, Kevin; Maleki, Sepideh; Jacobs, Elizabeth R; Audi, Said; Ranji, Mahsa

    2012-04-01

    Ventilation with enhanced fractions of O(2) (hyperoxia) is a common and necessary treatment for hypoxemia in patients with lung failure, but prolonged exposure to hyperoxia causes lung injury. Ischemia-reperfusion (IR) injury of lung tissue is common in lung transplant or crush injury to the chest. These conditions are associated with apoptosis and decreased survival of lung tissue. The objective of this work is to use cryoimaging to evaluate the effect of exposure to hyperoxia and IR injury on lung tissue mitochondrial redox state in rats. The autofluorescent mitochondrial metabolic coenzymes nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) are electron carriers in ATP generation. These intrinsic fluorophores were imaged for rat lungs using low-temperature fluorescence imaging (cryoimaging). Perfused lungs from four groups of rats were studied: normoxia (control), control perfused with an mitochondrial complex IV inhibitor (potassium cyanide, KCN), rats exposed to hyperoxia (85% O(2)) for seven days, and from rats subjected to lung IR in vivo 24 hours prior to study. Each lung was sectioned sequentially in the transverse direction, and the images were used to reconstruct a three-dimensional (3-D) rendering. In KCN perfused lungs the respiratory chain was more reduced, whereas hyperoxic and IR lung tissue have a more oxidized respiratory chain than control lung tissue, consistent with previously measured mitochondrial dysfunction in both hyperoxic and IR lungs.

  9. Optical imaging of tissue mitochondrial redox state in intact rat lungs in two models of pulmonary oxidative stress

    NASA Astrophysics Data System (ADS)

    Sepehr, Reyhaneh; Staniszewski, Kevin; Maleki, Sepideh; Jacobs, Elizabeth R.; Audi, Said; Ranji, Mahsa

    2012-04-01

    Ventilation with enhanced fractions of O2 (hyperoxia) is a common and necessary treatment for hypoxemia in patients with lung failure, but prolonged exposure to hyperoxia causes lung injury. Ischemia-reperfusion (IR) injury of lung tissue is common in lung transplant or crush injury to the chest. These conditions are associated with apoptosis and decreased survival of lung tissue. The objective of this work is to use cryoimaging to evaluate the effect of exposure to hyperoxia and IR injury on lung tissue mitochondrial redox state in rats. The autofluorescent mitochondrial metabolic coenzymes nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) are electron carriers in ATP generation. These intrinsic fluorophores were imaged for rat lungs using low-temperature fluorescence imaging (cryoimaging). Perfused lungs from four groups of rats were studied: normoxia (control), control perfused with an mitochondrial complex IV inhibitor (potassium cyanide, KCN), rats exposed to hyperoxia (85% O2) for seven days, and from rats subjected to lung IR in vivo 24 hours prior to study. Each lung was sectioned sequentially in the transverse direction, and the images were used to reconstruct a three-dimensional (3-D) rendering. In KCN perfused lungs the respiratory chain was more reduced, whereas hyperoxic and IR lung tissue have a more oxidized respiratory chain than control lung tissue, consistent with previously measured mitochondrial dysfunction in both hyperoxic and IR lungs.

  10. Perfusion patterns of ischemic stroke on computed tomography perfusion.

    PubMed

    Lin, Longting; Bivard, Andrew; Parsons, Mark W

    2013-09-01

    CT perfusion (CTP) has been applied increasingly in research of ischemic stroke. However, in clinical practice, it is still a relatively new technology. For neurologists and radiologists, the challenge is to interpret CTP results properly in the context of the clinical presentation. In this article, we will illustrate common CTP patterns in acute ischemic stroke using a case-based approach. The aim is to get clinicians more familiar with the information provided by CTP with a view towards inspiring them to incorporate CTP in their routine imaging workup of acute stroke patients.

  11. Myocardial perfusion assessment with contrast echocardiography

    NASA Astrophysics Data System (ADS)

    Desco, Manuel; Ledesma-Carbayo, Maria J.; Santos, Andres; Garcia-Fernandez, Miguel A.; Marcos-Alberca, Pedro; Malpica, Norberto; Antoranz, Jose C.; Garcia-Barreno, Pedro

    2001-05-01

    Assessment of intramyocardial perfusion by contrast echocardiography is a promising new technique that allows to obtain quantitative parameters for the assessment of ischemic disease. In this work, a new methodology and a software prototype developed for this task are presented. It has been validated with Coherent Contrast Imaging (CCI) images acquired with an Acuson Sequoia scanner. Contrast (Optison microbubbles) is injected continuously during the scan. 150 images are acquired using low mechanical index U/S pulses. A burst of high mechanical index pulses is used to destroy bubbles, thus allowing to detect the contrast wash-in. The stud is performed in two conditions: rest and pharmacologically induced stress. The software developed allows to visualized the study (cine) and to select several ROIs within the heart wall. The position of these ROIs along the cardiac cycle is automatically corrected on the basis of the gradient field, and they can also be manually corrected in case the automatic procedure fails. Time curves are analyzed according to a parametric model that incorporates both contrast inflow rate and cyclic variations. Preliminary clinical results on 80 patients have allowed us to identify normal and pathological patterns and to establish the correlation of quantitative parameters with the real diagnosis.

  12. Optic Disc Perfusion in Primary Open Angle and Normal Tension Glaucoma Eyes Using Optical Coherence Tomography-Based Microangiography

    PubMed Central

    Wen, Joanne C.; Zhang, Qinqin; Xin, Chen; Gupta, Divakar; Mudumbai, Raghu C.; Johnstone, Murray A.; Wang, Ruikang K.; Chen, Philip P.

    2016-01-01

    Purpose To investigate optic disc perfusion differences in normal, primary open-angle glaucoma (POAG), and normal tension glaucoma (NTG) eyes using optical microangiography (OMAG) based optical coherence tomography (OCT) angiography technique. Design Cross-sectional, observational study. Subjects Twenty-eight normal, 30 POAG, and 31 NTG subjects. Methods One eye from each subject was scanned with a 68 kHz Cirrus HD-OCT 5,000-based OMAG prototype system centered at the optic nerve head (ONH) (Carl Zeiss Meditec Inc, Dublin, CA). Microvascular images were generated from the OMAG dataset by detecting the differences in OCT signal between consecutive B-scans. The pre-laminar layer (preLC) was isolated by a semi-automatic segmentation program. Main Outcome Measures Optic disc perfusion, quantified as flux, vessel area density, and normalized flux (flux normalized by the vessel area) within the ONH. Results Glaucomatous eyes had significantly lower optic disc perfusion in preLC in all three perfusion metrics (p<0.0001) compared to normal eyes. The visual field (VF) mean deviation (MD) and pattern standard deviation (PSD) were similar between the POAG and NTG groups, and no differences in optic disc perfusion were observed between POAG and NTG. Univariate analysis revealed significant correlation between optic disc perfusion and VF MD, VF PSD, and rim area in both POAG and NTG groups (p≤0.0288). However, normalized optic disc perfusion was correlated with some structural measures (retinal nerve fiber layer thickness and ONH cup/disc ratio) only in POAG eyes. Conclusions Optic disc perfusion detected with OMAG was significantly reduced in POAG and NTG groups compared to normal controls, but no difference was seen between POAG and NTG groups with similar levels of VF damage. Disc perfusion was significantly correlated with VF MD, VF PSD, and rim area in glaucomatous eyes. Vascular changes at the optic disc as measured using OMAG may provide useful information for

  13. Optic nerve head perfusion in normal eyes and eyes with glaucoma using optical coherence tomography-based microangiography

    PubMed Central

    Chen, Chieh-Li; Bojikian, Karine D.; Gupta, Divakar; Wen, Joanne C.; Zhang, Qinqin; Xin, Chen; Kono, Rei; Mudumbai, Raghu C.; Johnstone, Murray A.; Chen, Philip P.

    2016-01-01

    Background To investigate the differences of perfusion in the optic nerve head (ONH) between normal and glaucomatous eyes using optical microangiography (OMAG) based optical coherence tomography (OCT) angiography technique. Methods One eye from each subject was scanned with a 68 kHz Cirrus 5000 HD-OCT-based OMAG prototype system centered at the ONH (Carl Zeiss Meditec Inc, Dublin, CA, USA). Microvascular images were generated from the OMAG dataset by detecting the differences in OCT signal between consecutive B-scans. The pre-laminar layer (preLC) was isolated by a semi-automatic segmentation program. En face OMAG images for preLC were generated using signals with highest blood flow signal intensity. ONH perfusion was quantified as flux, vessel area density, and normalized flux within the ONH. Standard t-tests were performed to analyze the ONH perfusion differences between normal and glaucomatous eyes. Linear regression models were constructed to analyze the correlation between ONH perfusion and other clinical measurements. Results Twenty normal and 21 glaucoma subjects were enrolled. Glaucomatous eyes had significantly lower ONH perfusion in preLC in all three perfusion metrics compared to normal eyes (P≤0.0003). Significant correlations between ONH perfusion and disease severity as well as structural changes were detected in glaucomatous eyes (P≤0.012). Conclusions ONH perfusion detected by OMAG showed significant differences between glaucoma and normal controls and was significantly correlated with disease severity and structural defects in glaucomatous eyes. ONH perfusion measurement using OMAG may provide useful information for detection and monitoring of glaucoma. PMID:27190764

  14. Computation of ventilation-perfusion ratio with Kr-81m in pulmonary embolism

    SciTech Connect

    Meignan, M.; Simonneau, G.; Oliveira, L.; Harf, A.; Cinotti, L.; Cavellier, J.F.; Duroux, P.; Ansquer, J.C.; Galle, P.

    1984-02-01

    Diagnostic difficulties occur in pulmonary embolism (PE) during visual analysis of ventilation-perfusion images in matched defects or in chronic obstructive lung disease (COPD). In 44 patients with angiographically confirmed PE and in 40 patients with COPD, the regional ventilation-perfusion ratios (V/Q) were therefore computed using krypton-81m for each perfusion defect, and were displayed in a functional image. In patients with PE and mismatched defects, a high V/Q (1.96) was observed. A V/Q > 1.25 was also found in nine of 11 patients having PE and indeterminate studies (studies with perfusion abnormalities matched by radiographic abnormalities). COPD was characterized by matched defects and low V/Q. The percentage of patients correctly classified as having PE or COPD increased from 56% when considering the match or mismatched character to 88% when based on a V/Q of 1.25 in the region of the perfusion defect. This quantitative analysis, therefore, seems useful in classifying patients with scintigraphic suspicion of PE.

  15. Intestinal perfusion monitoring using photoplethysmography

    PubMed Central

    Wilson, Mark A.; Ericson, M. Nance; Coté, Gerard L.

    2013-01-01

    Abstract. In abdominal trauma patients, monitoring intestinal perfusion and oxygen consumption is essential during the resuscitation period. Photoplethysmography is an optical technique potentially capable of monitoring these changes in real time to provide the medical staff with a timely and quantitative measure of the adequacy of resuscitation. The challenges for using optical techniques in monitoring hemodynamics in intestinal tissue are discussed, and the solutions to these challenges are presented using a combination of Monte Carlo modeling and theoretical analysis of light propagation in tissue. In particular, it is shown that by using visible wavelengths (i.e., 470 and 525 nm), the perfusion signal is enhanced and the background contribution is decreased compared with using traditional near-infrared wavelengths leading to an order of magnitude enhancement in the signal-to-background ratio. It was further shown that, using the visible wavelengths, similar sensitivity to oxygenation changes could be obtained (over 50% compared with that of near-infrared wavelengths). This is mainly due to the increased contrast between tissue and blood in that spectral region and the confinement of the photons to the thickness of the small intestine. Moreover, the modeling results show that the source to detector separation should be limited to roughly 6 mm while using traditional near-infrared light, with a few centimeters source to detector separation leads to poor signal-to-background ratio. Finally, a visible wavelength system is tested in an in vivo porcine study, and the possibility of monitoring intestinal perfusion changes is showed. PMID:23942635

  16. Respiratory tract exacerbations revisited: ventilation, inflammation, perfusion, and structure (VIPS) monitoring to redefine treatment.

    PubMed

    Tiddens, Harm A W M; Stick, Stephen M; Wild, Jim M; Ciet, Pierluigi; Parker, Geoffrey J M; Koch, Armin; Vogel-Claussen, Jens

    2015-10-01

    For cystic fibrosis (CF) patients older than 6 years there are convincing data that suggest respiratory tract exacerbations (RTE) play an important role in the progressive loss of functional lung tissue. There is a poor understanding of the pathobiology of RTE and whether specific treatment of RTE reduces lung damage in the long term. In addition, there are limited tools available to measure the various components of CF lung disease and responses to therapy. Therefore, in order to better understand the impact of RTE on CF lung disease we need to develop sensitive measures to characterize RTE and responses to treatment; and improve our understanding of structure-function changes during treatment of RTE. In this paper we review our current knowledge of the impact of RTE on the progression of lung disease and identify strategies to improve our understanding of the pathobiology of RTE. By improving our knowledge regarding RTE in CF we will be better positioned to develop approaches to treatment that are individualized and that can prevent permanent structural damage. We suggest the development of a ventilation, perfusion, inflammation and structure (VIPS)-MRI suite that supplies the clinician with data on ventilation, inflammation, perfusion, and structure in one MRI session. VIPS-MRI could be an important step to better understand the factors that contribute to and limit treatment efficacy of RTE. PMID:26335955

  17. Respiratory tract exacerbations revisited: ventilation, inflammation, perfusion, and structure (VIPS) monitoring to redefine treatment.

    PubMed

    Tiddens, Harm A W M; Stick, Stephen M; Wild, Jim M; Ciet, Pierluigi; Parker, Geoffrey J M; Koch, Armin; Vogel-Claussen, Jens

    2015-10-01

    For cystic fibrosis (CF) patients older than 6 years there are convincing data that suggest respiratory tract exacerbations (RTE) play an important role in the progressive loss of functional lung tissue. There is a poor understanding of the pathobiology of RTE and whether specific treatment of RTE reduces lung damage in the long term. In addition, there are limited tools available to measure the various components of CF lung disease and responses to therapy. Therefore, in order to better understand the impact of RTE on CF lung disease we need to develop sensitive measures to characterize RTE and responses to treatment; and improve our understanding of structure-function changes during treatment of RTE. In this paper we review our current knowledge of the impact of RTE on the progression of lung disease and identify strategies to improve our understanding of the pathobiology of RTE. By improving our knowledge regarding RTE in CF we will be better positioned to develop approaches to treatment that are individualized and that can prevent permanent structural damage. We suggest the development of a ventilation, perfusion, inflammation and structure (VIPS)-MRI suite that supplies the clinician with data on ventilation, inflammation, perfusion, and structure in one MRI session. VIPS-MRI could be an important step to better understand the factors that contribute to and limit treatment efficacy of RTE.

  18. Ventilation-perfusion matching during exercise

    NASA Technical Reports Server (NTRS)

    Wagner, P. D.

    1992-01-01

    In normal subjects, exercise widens the alveolar-arterial PO2 difference (P[A-a]O2) despite a more uniform topographic distribution of ventilation-perfusion (VA/Q) ratios. While part of the increase in P(A-a)O2 (especially during heavy exercise) is due to diffusion limitation, a considerable amount is caused by an increase in VA/Q mismatch as detected by the multiple inert gas elimination technique. Why this occurs is unknown, but circumstantial evidence suggests it may be related to interstitial pulmonary edema rather than to factors dependent on ventilation, airway gas mixing, airway muscle tone, or pulmonary vascular tone. In patients with lung disease, the gas exchange consequences of exercise are variable. Thus, arterial PO2 may increase, remain the same, or fall. In general, patients with advanced chronic obstructive pulmonary disease (COPD) or interstitial fibrosis who exercise show a fall in PO2. This is usually not due to worsening VA/Q relationships but mostly to the well-known fall in mixed venous PO2, which itself results from a relatively smaller increase in cardiac output than VO2. However, in interstitial fibrosis (but not COPD), there is good evidence that a part of the fall in PO2 on exercise is caused by alveolar-capillary diffusion limitation of O2 transport; in COPD (but not interstitial fibrosis), a frequent additional contributing factor to the hypoxemia of exercise is an inadequate ventilatory response, such that minute ventilation does not rise as much as does CO2 production or O2 uptake, causing arterial PCO2 to increase and PO2 to fall.

  19. Lung transplant

    MedlinePlus

    Solid organ transplant - lung ... the new lung Have severe disease of other organs Cannot reliably take their medicines Are unable to ... medicines Damage to your kidneys, liver, or other organs from anti-rejection medicines Future risk of certain ...

  20. Lung surgery

    MedlinePlus

    ... Pneumonectomy; Lobectomy; Lung biopsy; Thoracoscopy; Video-assisted thoracoscopic surgery; VATS ... You will have general anesthesia before surgery. You will be asleep and unable to feel pain. Two common ways to do surgery on your lungs are thoracotomy and video- ...

  1. Long term perfusion system supporting adipogenesis.

    PubMed

    Abbott, Rosalyn D; Raja, Waseem K; Wang, Rebecca Y; Stinson, Jordan A; Glettig, Dean L; Burke, Kelly A; Kaplan, David L

    2015-08-01

    Adipose tissue engineered models are needed to enhance our understanding of disease mechanisms and for soft tissue regenerative strategies. Perfusion systems generate more physiologically relevant and sustainable adipose tissue models, however adipocytes have unique properties that make culturing them in a perfusion environment challenging. In this paper we describe the methods involved in the development of two perfusion culture systems (2D and 3D) to test their applicability for long term in vitro adipogenic cultures. It was hypothesized that a silk protein biomaterial scaffold would provide a 3D framework, in combination with perfusion flow, to generate a more physiologically relevant sustainable adipose tissue engineered model than 2D cell culture. Consistent with other studies evaluating 2D and 3D culture systems for adipogenesis we found that both systems successfully model adipogenesis, however 3D culture systems were more robust, providing the mechanical structure required to contain the large, fragile adipocytes that were lost in 2D perfused culture systems. 3D perfusion also stimulated greater lipogenesis and lipolysis and resulted in decreased secretion of LDH compared to 2D perfusion. Regardless of culture configuration (2D or 3D) greater glycerol was secreted with the increased nutritional supply provided by perfusion of fresh media. These results are promising for adipose tissue engineering applications including long term cultures for studying disease mechanisms and regenerative approaches, where both acute (days to weeks) and chronic (weeks to months) cultivation are critical for useful insight. PMID:25843606

  2. Sumatriptan and cerebral perfusion in healthy volunteers.

    PubMed

    Scott, A K; Grimes, S; Ng, K; Critchley, M; Breckenridge, A M; Thomson, C; Pilgrim, A J

    1992-04-01

    1. The effect of sumatriptan on regional cerebral perfusion was studied in healthy volunteers. 2. Intravenous sumatriptan (2 mg) had no detectable effect on regional cerebral perfusion as measured using a SPECT system with 99technetiumm labelled hexemethylpropyleneamineoxime. 3. Sumatriptan had no effect on pulse, blood pressure or ECG indices. 4. All six volunteers experienced minor adverse effects during the intravenous infusion.

  3. Personality factors correlate with regional cerebral perfusion.

    PubMed

    O'Gorman, R L; Kumari, V; Williams, S C R; Zelaya, F O; Connor, S E J; Alsop, D C; Gray, J A

    2006-06-01

    There is an increasing body of evidence pointing to a neurobiological basis of personality. The purpose of this study was to investigate the biological bases of the major dimensions of Eysenck's and Cloninger's models of personality using a noninvasive magnetic resonance perfusion imaging technique in 30 young, healthy subjects. An unbiased voxel-based analysis was used to identify regions where the regional perfusion demonstrated significant correlation with any of the personality dimensions. Highly significant positive correlations emerged between extraversion and perfusion in the basal ganglia, thalamus, inferior frontal gyrus and cerebellum and between novelty seeking and perfusion in the cerebellum, cuneus and thalamus. Strong negative correlations emerged between psychoticism and perfusion in the basal ganglia and thalamus and between harm avoidance and perfusion in the cerebellar vermis, cuneus and inferior frontal gyrus. These observations suggest that personality traits are strongly associated with resting cerebral perfusion in a variety of cortical and subcortical regions and provide further evidence for the hypothesized neurobiological basis of personality. These results may also have important implications for functional neuroimaging studies, which typically rely on the modulation of cerebral hemodynamics for detection of task-induced activation since personality effects may influence the intersubject variability for both task-related activity and resting cerebral perfusion. This technique also offers a novel approach for the exploration of the neurobiological correlates of human personality.

  4. Long term perfusion system supporting adipogenesis

    PubMed Central

    Abbott, Rosalyn D.; Raja, Waseem K.; Wang, Rebecca Y.; Stinson, Jordan A.; Glettig, Dean L.; Burke, Kelly A.; Kaplan, David L.

    2015-01-01

    Adipose tissue engineered models are needed to enhance our understanding of disease mechanisms and for soft tissue regenerative strategies. Perfusion systems generate more physiologically relevant and sustainable adipose tissue models, however adipocytes have unique properties that make culturing them in a perfusion environment challenging. In this paper we describe the methods involved in the development of two perfusion culture systems (2D and 3D) to test their applicability for long term in vitro adipogenic cultures. It was hypothesized that a silk protein biomaterial scaffold would provide a 3D framework, in combination with perfusion flow, to generate a more physiologically relevant sustainable adipose tissue engineered model than 2D cell culture. Consistent with other studies evaluating 2D and 3D culture systems for adipogenesis we found that both systems successfully model adipogensis, however 3D culture systems were more robust, providing the mechanical structure required to contain the large, fragile adipocytes that were lost in 2D perfused culture systems. 3D perfusion also stimulated greater lipogenesis and lipolysis and resulted in decreased secretion of LDH compared to 2D perfusion. Regardless of culture configuration (2D or 3D) greater glycerol was secreted with the increased nutritional supply provided by perfusion of fresh media. These results are promising for adipose tissue engineering applications including long term cultures for studying disease mechanisms and regenerative approaches, where both acute (days to weeks) and chronic (weeks to months) cultivation are critical for useful insight. PMID:25843606

  5. Long term perfusion system supporting adipogenesis.

    PubMed

    Abbott, Rosalyn D; Raja, Waseem K; Wang, Rebecca Y; Stinson, Jordan A; Glettig, Dean L; Burke, Kelly A; Kaplan, David L

    2015-08-01

    Adipose tissue engineered models are needed to enhance our understanding of disease mechanisms and for soft tissue regenerative strategies. Perfusion systems generate more physiologically relevant and sustainable adipose tissue models, however adipocytes have unique properties that make culturing them in a perfusion environment challenging. In this paper we describe the methods involved in the development of two perfusion culture systems (2D and 3D) to test their applicability for long term in vitro adipogenic cultures. It was hypothesized that a silk protein biomaterial scaffold would provide a 3D framework, in combination with perfusion flow, to generate a more physiologically relevant sustainable adipose tissue engineered model than 2D cell culture. Consistent with other studies evaluating 2D and 3D culture systems for adipogenesis we found that both systems successfully model adipogenesis, however 3D culture systems were more robust, providing the mechanical structure required to contain the large, fragile adipocytes that were lost in 2D perfused culture systems. 3D perfusion also stimulated greater lipogenesis and lipolysis and resulted in decreased secretion of LDH compared to 2D perfusion. Regardless of culture configuration (2D or 3D) greater glycerol was secreted with the increased nutritional supply provided by perfusion of fresh media. These results are promising for adipose tissue engineering applications including long term cultures for studying disease mechanisms and regenerative approaches, where both acute (days to weeks) and chronic (weeks to months) cultivation are critical for useful insight.

  6. Visualization of an Incidental Ectopic Gallbladder Location on 99mTc-MIBI Myocardial Perfusion Imaging With SPECT/CT.

    PubMed

    Hou, Po-Nien; Huang, Cheng-Kai; Wu, Jay

    2016-03-01

    An ectopically located gallbladder is rare and unusual. In this study, we described a case of a 52-year-old woman who underwent SPECT-myocardial perfusion imaging because of exertional dyspnea and chest tightness. The rest sinograms reveal 2 substantially increased tracer uptakes in the right chest. Subsequently, a SPECT/CT scan was performed to clarify the indeterminate findings on the SPECT-myocardial perfusion imaging. The coregistered SPECT/CT images depict intense focal activity in the right chest, which corresponds to the gallbladder on the CT scan, thus explaining the peculiar ectopic gallbladder finding.

  7. [Assessing myocardial perfusion with positron emission tomography].

    PubMed

    vom Dahl, J

    2001-11-01

    Positron emission tomography (PET) of the heart has gained widespread scientific and clinical acceptance with regard to two indications: 1) The detection of perfusion abnormalities by qualitative and semiquantitative analyses of perfusion images at rest and during physical or pharmacological stress using well-validated perfusion tracers, such as N-13 ammonia, Rb-82 rubidium chloride, or O-15 labeled water. 2) Viability imaging of myocardial regions with reduced contractility by combining perfusion measurements with substrate metabolism as assessed from F-18 deoxyglucose utilization. This overview summarizes the use of PET as a perfusion imaging method. With a sensitivity > 90% in combination with high specificity, PET is today the best-validated available nuclear imaging technique for the diagnosis of coronary artery disease (CAD). The short half-life of the perfusion tracers in combination with highly sophisticated hard- and software enables rapid PET studies with high patient throughput. The high diagnostic accuracy and the methological advantages as compared to conventional scintigraphy allows one to use PET perfusion imaging to detect subtle changes in the perfusion reserve for the detection of CAD in high risk but asymptomatic patients as well as in patients with proven CAD undergoing various treatment forms such as risk factor reduction or coronary revascularization. In patients following orthotopic heart transplantation, evolving transplant vasculopathy can be detected at an early stage. Quantitative PET imaging at rest allows for detection of myocardial viability since cellular survival is based on maintenance of a minimal perfusion and structural changes correlate to the degree of perfusion reduction. Furthermore, quantitative assessment of the myocardial perfusion reserve detects the magnitude and competence of collaterals in regions with occluded epicardial collaterals and, thus, imaging of several coronary distribution territories in one noninvasive

  8. Head CT scan

    MedlinePlus

    Brain CT; Cranial CT; CT scan - skull; CT scan - head; CT scan - orbits; CT scan - sinuses; Computed tomography - cranial; CAT scan - brain ... conditions: Birth (congenital) defect of the head or brain Brain infection Brain tumor Buildup of fluid inside ...

  9. [Examination of Visual Effect in Low-dose Cerebral CT Perfusion Phantom Image Using Iterative Reconstruction].

    PubMed

    Ohmura, Tomomi; Lee, Yongbum; Takahashi, Noriyuki; Sato, Yuichiro; Ishida, Takato; Toyoshima, Hideto

    2015-11-01

    CT perfusion (CTP) is obtained cerebrovascular circulation image for assessment of stroke patients; however, at the expense of increased radiation dose by dynamic scan. Iterative reconstruction (IR) method is possible to decrease image noise, it has the potential to reduce radiation dose. The purpose of this study is to assess the visual effect of IR method by using a digital perfusion phantom. The digital perfusion phantom was created by reconstructed filtered back projection (FBP) method and IR method CT images that had five exposure doses. Various exposure dose cerebral blood flow (CBF) images were derived from deconvolution algorithm. Contrast-to-noise ratio (CNR) and visual assessment were compared among the various exposure dose and each reconstructions. Result of low exposure dose with IR method showed, compared with FBP method, high CNR in severe ischemic area, and visual assessment was significantly improvement. IR method is useful for improving image quality of low-dose CTP. PMID:26596197

  10. Perfusion and thallium single photon emission computed tomography in herpes simplex encephalitis.

    PubMed

    De Deyn, P P; Van den Broucke, P W; Pickut, B A; Appel, B; Crols, R; Cras, P; Martin, J J

    1998-04-15

    This is the first report on 201thallium-single photon emission computed tomography (201Tl-SPECT) brain scan of a patient with herpes simplex encephalitis (HSE). The presented 201Tl-SPECT observations are correlated with 99mtechnetium hexamethylpropylene amine oxime (99mTc-HMPAO) perfusion SPECT and magnetic resonance imaging (MRI) findings. Brain 99mTc-HMPAO perfusion SPECT reveals a hyperperfusion in the right temporal lobe with extension to the parietal lobe and a hypoperfusion in the ipsilateral occipital lobe. 201Tl-SPECT shows a fixation in the right temporal lobe coinciding with the gadolinium enhancement on MRI. The right occipital lesion shown by gadolinium captation on MRI and hypoperfusion on 99mTc-HMPAO perfusion SPECT was not evident on the 201Tl SPECT. These findings could illustrate that the lesions might be different pathophysiologically.

  11. Dopamine transporter SPECT/CT and perfusion brain SPECT imaging in idiopathic basal ganglia calcinosis.

    PubMed

    Paschali, Anna; Lakiotis, Velissarios; Messinis, Lambros; Markaki, Elli; Constantoyannis, Constantine; Ellul, John; Vassilakos, Pavlos

    2009-07-01

    A case of idiopathic basal ganglia calcification in a 56-year-old woman with parkinsonism and cognitive impairment is described. The nigrostriatal dopaminergic pathway and regional cerebral blood flow were evaluated using dopamine transporter (DAT) brain single photon emission tomography combined with a low-dose x-ray computerized tomography transmission (hybrid SPECT/CT) and Tc-99m HMPAO brain perfusion SPECT study, respectively. DAT SPECT/CT imaging revealed a reduction in DAT binding in both striatum regions coinciding with bilateral calcifications in the basal ganglia. Brain perfusion scan showed hypoperfusion in basal ganglia regions, posterior parietal cortex bilaterally, left frontopolar and dorsolateral prefrontal cortex, and left temporal lobe. These findings correlated well with the clinical condition of the patient. Mineralization may play a critical role in the pathogenesis of neuronal degeneration. Cortical perfusion changes in patients may better explain the patient's altered cognitive and motor functions.

  12. Redistribution of pulmonary blood flow impacts thermodilution-based extravascular lung water measurements in a model of acute lung injury

    PubMed Central

    Easley, R. Blaine; Mulreany, Daniel G.; Lancaster, Christopher T.; Custer, Jason W.; Fernandez-Bustamante, Ana; Colantuoni, Elizabeth; Simon, Brett A.

    2009-01-01

    Background Studies using transthoracic thermodilution have demonstrated increased extravascular lung water (EVLW) measurements attributed to progression of edema and flooding during sepsis and acute lung injury. We hypothesize that redistribution of pulmonary blood flow can cause increased apparent EVLW secondary to increased perfusion of thermally silent tissue, not increased lung edema. Methods Anesthetized, mechanically ventilated canines were instrumented with PiCCO® (Pulsion Medical, Munich, Germany) catheters and underwent lung injury by repetitive saline lavage. Hemodynamic and respiratory physiologic data were recorded. After stabilized lung injury, endotoxin was administered to inactivate hypoxic pulmonary vasoconstriction. Computerized tomographic imaging was performed to quantify in vivo lung volume, total tissue (fluid) and air content, and regional distribution of blood flow. Results Lavage injury caused an increase in airway pressures and decreased arterial oxygen content with minimal hemodynamic effects. EVLW and shunt fraction increased after injury and then markedly following endotoxin administration. Computerized tomographic measurements quantified an endotoxin-induced increase in pulmonary blood flow to poorly aerated regions with no change in total lung tissue volume. Conclusions The abrupt increase in EVLW and shunt fraction after endotoxin administration is consistent with inactivation of hypoxic pulmonary vasoconstriction and increased perfusion to already flooded lung regions that were previously thermally silent. Computerized tomographic studies further demonstrate in vivo alterations in regional blood flow (but not lung water) and account for these alterations in shunt fraction and EVLW. PMID:19809280

  13. Lung Organogenesis

    PubMed Central

    Warburton, David; El-Hashash, Ahmed; Carraro, Gianni; Tiozzo, Caterina; Sala, Frederic; Rogers, Orquidea; De Langhe, Stijn; Kemp, Paul J.; Riccardi, Daniela; Torday, John; Bellusci, Saverio; Shi, Wei; Lubkin, Sharon R; Jesudason, Edwin

    2011-01-01

    Developmental lung biology is a field that has the potential for significant human impact: lung disease at the extremes of age continues to cause major morbidity and mortality worldwide. Understanding how the lung develops holds the promise that investigators can use this knowledge to aid lung repair and regeneration. In the decade since the “molecular embryology” of the lung was first comprehensively reviewed, new challenges have emerged—and it is on these that we focus the current review. Firstly, there is a critical need to understand the progenitor cell biology of the lung in order to exploit the potential of stem cells for the treatment of lung disease. Secondly, the current familiar descriptions of lung morphogenesis governed by growth and transcription factors need to be elaborated upon with the reinclusion and reconsideration of other factors, such as mechanics, in lung growth. Thirdly, efforts to parse the finer detail of lung bud signaling may need to be combined with broader consideration of overarching mechanisms that may be therapeutically easier to target: in this arena, we advance the proposal that looking at the lung in general (and branching in particular) in terms of clocks may yield unexpected benefits. PMID:20691848

  14. The influence of hydralazine on the vasculature, blood perfusion and chemosensitivity of MAC tumours.

    PubMed

    Quinn, P K; Bibby, M C; Cox, J A; Crawford, S M

    1992-08-01

    We have studied the influence of the peripheral vasodilator hydralazine (HDZ) on the vasculature and blood perfusion of two members of a series of subcutaneous murine adenocarcinomata of the colon (MAC tumours), and the influence of HDZ on the efficacy and/or toxicity of TCNU and melphalan. The fluorescent DNA stain Hoechst 33342, showed that HDZ caused a shutdown of tumour vasculature, related in magnitude to both dose and tumour differentiation state; 10 mg kg-1 caused an 80% vascular shutdown of well differentiated MAC 26 tumours, but only a 50% shutdown of the poorly differentiated MAC 15A tumours. 2.5 mg kg-1 was ineffective. The blood perfusion marker 99mTc-HMPAO showed that the normal perfusion of MAC tumours was consistently markedly less than that of lung, liver or kidneys (4-5% of lung perfusion). HDZ (10 mg kg-1) decreased MAC 26 perfusion by 63%, and that of MAC 15A by 20%. Again, 2.5 mg kg-1) was ineffective. Use of in vivo to in vitro clonogenic assays showed that HDZ (10 mg kg-1) potentiated the efficacy of melphalan (1-10 mg kg-1 i.p.) by a factor of 2.1, and increased the efficacy of TCNU (1-10 mg kg-1 i.v., factor = 1.7) when given 10 or 15 min respectively after dosing. However, the addition of HDZ increased the acute bone marrow toxicity of melphalan, but not that of TCNU. The clinical relevance of these results is discussed.

  15. Current status of pig lung xenotransplantation.

    PubMed

    Kubicki, Natalia; Laird, Christopher; Burdorf, Lars; Pierson, Richard N; Azimzadeh, Agnes M

    2015-11-01

    Human organ transplantation has improved duration and quality of life for many people, but its full potential is critically limited by short supply of available organs. One solution is xenotransplantation, although this comes with its own set of challenges. Lungs in particular are highly sensitive to injury, during the transplantation process generally, and to multiple immune rejection mechanisms. Using pig lung donors, our lab has been working on lung transplants into baboons as a surrogate for a human recipient. Several ex vivo human blood perfusion models have also proven useful. The combination of these experiments allows us to test large animal models as well as whole organ or isolated endothelial reactions to perfusion with human blood. We have found that a multi-modality therapeutic approach to prevent various pathogenic cascades - such as antibody-driven complement activation, other immune pathway activation, thrombosis, and tissue ischemia-reperfusion injury - has met with progressively greater success to protect the xeno lung from injury. Pig gene knockout and human gene transfer has been perhaps the greatest contributor. This review will discuss mechanisms of xeno lung injury, relevant experimental models, as well as recent results and future targets for research.

  16. Lung ultrasound: Present and future.

    PubMed

    Saraogi, Ashish

    2015-01-01

    The scope of lung ultrasound (LUS) in emergency and critical care settings has been studied extensively. LUS is easily available at bedside, free of radiation hazard and real time. All these features make it useful in reducing need of bedside X-rays and CT scan of chest. LUS has been proven to be superior to the bedside chest X-ray and equal to chest CT in diagnosing many pleural and lung pathologies. The first International Consensus Conference on Lung Ultrasound (ICC-LUS) has given recommendations for unified approach and language in major six areas of LUS. The LUS diagnosis is to be given after integration of findings of both lungs. The BLUE protocol is first LUS-based systematic approach in diagnosing pleural and lung pathologies. The protocol suggested in this article includes history and conventional clinical assessment along with LUS features. PMID:25983411

  17. Brain perfusion correlates of visuoperceptual deficits in Mild Cognitive Impairment and mild Alzheimer’s disease

    PubMed Central

    Alegret, Montserrat; Vinyes-Junqué, Georgina; Boada, Mercè; Martínez-Lage, Pablo; Cuberas, Gemma; Espinosa, Ana; Roca, Isabel; Hernández, Isabel; Valero, Sergi; Rosende-Roca, Maitée; Mauleón, Ana; Becker, James T.; Tárraga, Lluís

    2012-01-01

    Background Visuoperceptual processing is impaired early in the clinical course of Alzheimer’s disease (AD). The 15-Objects Test (15-OT) detects such subtle performance deficits in Mild Cognitive Impairment (MCI) and mild AD. Reduced brain perfusion in the temporal, parietal and prefrontal regions have been found in early AD and MCI patients. Objectives To confirm the role of the 15-OT in the diagnosis of MCI and AD, and to investigate the brain perfusion correlates of visuoperceptual dysfunction (15-OT) in subjects with MCI, AD and normal aging. Methods Forty-two AD, 42 MCI and 42 healthy elderly control (EC) subjects underwent a brain Single Photon Emission Tomography (SPECT) and separately completed the 15-OT. An analysis of variance compared 15-OT scores between groups. SPM5 was used to analyse the SPECT data. Results 15-OT performace was impaired in the MCI and AD patients. In terms of the SPECT scans, AD patients showed reduced perfusion in temporal-parietal regions, while the MCI subjects had decreased perfusion in the middle and posterior cingulate. When MCI and AD groups were compared, a significant brain perfusion reduction was found in temporo-parietal regions. In the whole sample, 15-OT performance was significantly correlated with the clinical dementia rating scores, and with the perfusion in the bilateral posterior cingulate and the right temporal pole, with no significant correlation in each separate group. Conclusion Our findings suggest that the 15-OT performance provides a useful gradation of impairment from normal aging to AD, and it seems to be related to perfusion in the bilateral posterior cingulate and the right temporal pole. PMID:20555146

  18. Permissive hypotension does not reduce regional organ perfusion compared to normotensive resuscitation: animal study with fluorescent microspheres

    PubMed Central

    2012-01-01

    Introduction The objective of this study was to investigate regional organ perfusion acutely following uncontrolled hemorrhage in an animal model that simulates a penetrating vascular injury and accounts for prehospital times in urban trauma. We set forth to determine if hypotensive resuscitation (permissive hypotension) would result in equivalent organ perfusion compared to normotensive resuscitation. Methods Twenty four (n=24) male rats randomized to 4 groups: Sham, No Fluid (NF), Permissive Hypotension (PH) (60% of baseline mean arterial pressure - MAP), Normotensive Resuscitation (NBP). Uncontrolled hemorrhage caused by a standardised injury to the abdominal aorta; MAP was monitored continuously and lactated Ringer’s was infused. Fluorimeter readings of regional blood flow of the brain, heart, lung, kidney, liver, and bowel were obtained at baseline and 85 minutes after hemorrhage, as well as, cardiac output, lactic acid, and laboratory tests; intra-abdominal blood loss was assessed. Analysis of variance was used for comparison. Results Intra-abdominal blood loss was higher in NBP group, as well as, lower hematocrit and hemoglobin levels. No statistical differences in perfusion of any organ between PH and NBP groups. No statistical difference in cardiac output between PH and NBP groups, as well as, in lactic acid levels between PH and NBP. NF group had significantly higher lactic acidosis and had significantly lower organ perfusion. Conclusions Hypotensive resuscitation causes less intra-abdominal bleeding than normotensive resuscitation and concurrently maintains equivalent organ perfusion. No fluid resuscitation reduces intra-abdominal bleeding but also significantly reduces organ perfusion. PMID:23531188

  19. SU-E-I-36: A KWIC and Dirty Look at Dose Savings and Perfusion Metrics in Simulated CT Neuro Perfusion Exams

    SciTech Connect

    Hoffman, J; Martin, T; Young, S; McNitt-Gray, M; Wang, D

    2015-06-15

    Purpose: CT neuro perfusion scans are one of the highest dose exams. Methods to reduce dose include decreasing the number of projections acquired per gantry rotation, however conventional reconstruction of such scans leads to sampling artifacts. In this study we investigated a projection view-sharing reconstruction algorithm used in dynamic MRI – “K-space Weighted Image Contrast” (KWIC) – applied to simulated perfusion exams and evaluated dose savings and impacts on perfusion metrics. Methods: A FORBILD head phantom containing simulated time-varying objects was developed and a set of parallel-beam CT projection data was created. The simulated scans were 60 seconds long, 1152 projections per turn, with a rotation time of one second. No noise was simulated. 5mm, 10mm, and 50mm objects were modeled in the brain. A baseline, “full dose” simulation used all projections and reduced dose cases were simulated by downsampling the number of projections per turn from 1152 to 576 (50% dose), 288 (25% dose), and 144 (12.5% dose). KWIC was further evaluated at 72 projections per rotation (6.25%). One image per second was reconstructed using filtered backprojection (FBP) and KWIC. KWIC reconstructions utilized view cores of 36, 72, 144, and 288 views and 16, 8, 4, and 2 subapertures respectively. From the reconstructed images, time-to-peak (TTP), cerebral blood flow (CBF) and the FWHM of the perfusion curve were calculated and compared against reference values from the full-dose FBP data. Results: TTP, CBF, and the FWHM were unaffected by dose reduction (to 12.5%) and reconstruction method, however image quality was improved when using KWIC. Conclusion: This pilot study suggests that KWIC preserves image quality and perfusion metrics when under-sampling projections and that the unique contrast weighting of KWIC could provided substantial dose-savings for perfusion CT scans. Evaluation of KWIC in clinical CT data will be performed in the near future. R01 EB014922, NCI

  20. Human T-cell Lymphotropic Virus Type-1 (HTLV-1)-associated Bronchioloalveolar Disorder Presenting with Mosaic Perfusion.

    PubMed

    Yamakawa, Hideaki; Yoshida, Masahiro; Yabe, Masami; Ishikawa, Takeo; Takagi, Masamichi; Tanoue, Susumu; Sano, Koji; Nishiwaki, Kaichi; Sato, Shun; Shimizu, Yoshihiko; Kuwano, Kazuyoshi

    2015-01-01

    Human T-cell lymphotropic virus type-1 (HTLV-1)-associated bronchioloalveolar disorder (HABA) is a specific state with chronic and progressive respiratory symptoms caused by bronchiolar or alveolar disorder characterized by smoldering adult T-cell leukemia or the HTLV-I carrier state. We herein report a rare case of HABA with an initial presentation of mosaic perfusion in the lung. The diagnosis was made according to the results of a flow cytometry analysis of the bronchoalveolar lavage fluid and pathological findings. Clinicians must be careful to recognize that mosaic perfusion may be a radiological finding of HABA. PMID:26631889

  1. Comparative study of two perfusion routes with different flow in decellularization to harvest an optimal pulmonary scaffold for recellularization.

    PubMed

    Wang, Zhiyi; Wang, Zhibin; Yu, Qing; Xi, Haitao; Weng, Jie; Du, Xiaohong; Chen, Daqing; Ma, Jianshe; Mei, Jin; Chen, Chan

    2016-10-01

    Decellularization processes may variably distort or degrade extracellular matrix (ECM) structure. In this study, two perfusion routes (PR) were tested on SD rat lung samples. One decellularization protocol, PR1, was perfused through the pulmonary artery. The other decellularization protocol, PR2, was perfused through the trachea. Both decellularization protocols were used by the same detergent-based (sodium dodecyl sulphate and Triton X-100) with different flow continuous perfusion. There was no visible difference in vessel architecture between PR1- and PR2-decellularized scaffold. However, the airway structure and alveoli architecture of pulmonary decellularized scaffolds generated through PR2 at a flow rate of 8 mL/min were destroyed partly when compared to that in native lung and PR1-decellularized scaffold. Ultramicroscopic assessment of scaffolds was similar in both protocols and showed filamentous ECM with preserved fiber disposition and structure. Histological analysis and immunostaining showed no detectable cells remaining in the pulmonary scaffolds compare with native lung. The DNA concentration was significantly reduced in the decellularized scaffolds compared to the native lungs. A549 cells reseeded onto decellularized pulmonary scaffolds were no significant difference between PR1 and PR2 in cell viability, p > 0.05. We conclude that under the same high flow velocity status, perfusion decellularization through the pulmonary artery may be an optimal pathway to obtain decellularized scaffolds for pulmonary regeneration. This article is protected by copyright. All rights reserved. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 2567-2575, 2016. PMID:27227902

  2. Radiation dose reduction in computed tomography perfusion using spatial-temporal Bayesian methods

    NASA Astrophysics Data System (ADS)

    Fang, Ruogu; Raj, Ashish; Chen, Tsuhan; Sanelli, Pina C.

    2012-03-01

    In current computed tomography (CT) examinations, the associated X-ray radiation dose is of significant concern to patients and operators, especially CT perfusion (CTP) imaging that has higher radiation dose due to its cine scanning technique. A simple and cost-effective means to perform the examinations is to lower the milliampere-seconds (mAs) parameter as low as reasonably achievable in data acquisition. However, lowering the mAs parameter will unavoidably increase data noise and degrade CT perfusion maps greatly if no adequate noise control is applied during image reconstruction. To capture the essential dynamics of CT perfusion, a simple spatial-temporal Bayesian method that uses a piecewise parametric model of the residual function is used, and then the model parameters are estimated from a Bayesian formulation of prior smoothness constraints on perfusion parameters. From the fitted residual function, reliable CTP parameter maps are obtained from low dose CT data. The merit of this scheme exists in the combination of analytical piecewise residual function with Bayesian framework using a simpler prior spatial constrain for CT perfusion application. On a dataset of 22 patients, this dynamic spatial-temporal Bayesian model yielded an increase in signal-tonoise-ratio (SNR) of 78% and a decrease in mean-square-error (MSE) of 40% at low dose radiation of 43mA.

  3. Nearly total absence of pulmonary perfusion with corresponding technetium-99m MDP and gallium-67 uptake in a patient with mediastinal neuroblastoma

    SciTech Connect

    Garty, I.; Koren, A.; Moguilner, G.; Dharan, M.; Siplovitch, L.

    1985-08-01

    A case of unilateral nearly total hypoperfusion of the left lung in a 13-month-old girl is presented. The combination of the lung hypoperfusion and accumulation of the Tc-99m MDP and Ga-67 citrate in the same area suggested the preoperative diagnosis of mediastinal neuroblastoma. Explorative thoracotomy revealed the presence of a neuroblastoma compressing the left lung pedicle. The described scintigraphic appearance in the pediatric age group is suggested as typical of mediastinal neuroblastoma. This pathology should be included in the following gamuts in nuclear medicine: unilateral decrease or absent lung perfusion, unilateral diffuse chest uptake of Ga-67 citrate, and unilateral pulmonary uptake in bone scintigraphy.

  4. The mesenterially perfused rat small intestine: A versatile approach for pharmacological testings.

    PubMed

    Schreiber, Dominik; Klotz, Markus; Laures, Kerstin; Clasohm, Jasmin; Bischof, Michael; Schäfer, Karl-Herbert

    2014-05-01

    Pharmaceutical compounds enter the body via several major natural gateways; i.e. the lung, the skin and the gastrointestinal tract. Drug application during surgical operations can lead to severe impairment of gastrointestinal motility, which can contribute to a paralytic ileus. Here we investigated an ex vivo perfused small intestine model that allows us to ascertain the influence of pharmaceuticals upon the gut. Corresponding segments from the proximal jejunum of adult rats were used. Their mesenteric arteries and veins were cannulated and the jejunal segment excised. The individual segments were placed in a custom designed perfusion chamber and perfusion performed through the intestinal lumen as well as the mesenteric superior artery. Three test drugs, which are commonly used in anesthesiology; i.e. pentobarbital, propofol and ketamine were administered via the blood vessels. Their effects upon gastrointestinal motility patterns were evaluated by optical measurements. Longitudinal and pendular movements were distinguishable and separately analyzed. Pharmacological effects of the individual substances could be investigated. Propofol (50-200 μg/ml) was found to decrease intestinal motility, especially longitudinal movements in a dose dependent manner. Pentobarbital decreased intestinal motility only at high concentrations, above 2.5 mg/ml. A dose of 2.5 mg/ml lead to an increase in longitudinal- and pendular movements in comparison to control, while ketamine (2.5-10 mg/ml) did not alter intestinal motility at all. Histological examination of the perfused segments revealed only minor changes in tissue morphology after perfusion. The perfusion approach shown here allows for the identification of compounds which interfere with gut motility in a highly sophisticated way. It is suitable for characterization of drug and dose specific changes in motility patterns and can be used in drug development and preclinical studies.

  5. CT Perfusion of the Head

    MedlinePlus

    ... scanning combines special x-ray equipment with sophisticated computers to produce multiple images or pictures of the ... being studied can then be examined on a computer monitor, printed or transferred to a CD. CT ...

  6. Cochlear perfusion with a viscous fluid.

    PubMed

    Wang, Yi; Olson, Elizabeth S

    2016-07-01

    The flow of viscous fluid in the cochlea induces shear forces, which could provide benefit in clinical practice, for example to guide cochlear implant insertion or produce static pressure to the cochlear partition or wall. From a research standpoint, studying the effects of a viscous fluid in the cochlea provides data for better understanding cochlear fluid mechanics. However, cochlear perfusion with a viscous fluid may damage the cochlea. In this work we studied the physiological and anatomical effects of perfusing the cochlea with a viscous fluid. Gerbil cochleae were perfused at a rate of 2.4 μL/min with artificial perilymph (AP) and sodium hyaluronate (Healon, HA) in four different concentrations (0.0625%, 0.125%, 0.25%, 0.5%). The different HA concentrations were applied either sequentially in the same cochlea or individually in different cochleae. The perfusion fluid entered from the round window and was withdrawn from basal scala vestibuli, in order to perfuse the entire perilymphatic space. Compound action potentials (CAP) were measured after each perfusion. After perfusion with increasing concentrations of HA in the order of increasing viscosity, the CAP thresholds generally increased. The threshold elevation after AP and 0.0625% HA perfusion was small or almost zero, and the 0.125% HA was a borderline case, while the higher concentrations significantly elevated CAP thresholds. Histology of the cochleae perfused with the 0.0625% HA showed an intact Reissner's membrane (RM), while in cochleae perfused with 0.125% and 0.25% HA RM was torn. Thus, the CAP threshold elevation was likely due to the broken RM, likely caused by the shear stress produced by the flow of the viscous fluid. Our results and analysis indicate that the cochlea can sustain, without a significant CAP threshold shift, up to a 1.5 Pa shear stress. Beside these finding, in the 0.125% and 0.25% HA perfusion cases, a temporary CAP threshold shift was observed, perhaps due to the presence and

  7. Cochlear perfusion with a viscous fluid.

    PubMed

    Wang, Yi; Olson, Elizabeth S

    2016-07-01

    The flow of viscous fluid in the cochlea induces shear forces, which could provide benefit in clinical practice, for example to guide cochlear implant insertion or produce static pressure to the cochlear partition or wall. From a research standpoint, studying the effects of a viscous fluid in the cochlea provides data for better understanding cochlear fluid mechanics. However, cochlear perfusion with a viscous fluid may damage the cochlea. In this work we studied the physiological and anatomical effects of perfusing the cochlea with a viscous fluid. Gerbil cochleae were perfused at a rate of 2.4 μL/min with artificial perilymph (AP) and sodium hyaluronate (Healon, HA) in four different concentrations (0.0625%, 0.125%, 0.25%, 0.5%). The different HA concentrations were applied either sequentially in the same cochlea or individually in different cochleae. The perfusion fluid entered from the round window and was withdrawn from basal scala vestibuli, in order to perfuse the entire perilymphatic space. Compound action potentials (CAP) were measured after each perfusion. After perfusion with increasing concentrations of HA in the order of increasing viscosity, the CAP thresholds generally increased. The threshold elevation after AP and 0.0625% HA perfusion was small or almost zero, and the 0.125% HA was a borderline case, while the higher concentrations significantly elevated CAP thresholds. Histology of the cochleae perfused with the 0.0625% HA showed an intact Reissner's membrane (RM), while in cochleae perfused with 0.125% and 0.25% HA RM was torn. Thus, the CAP threshold elevation was likely due to the broken RM, likely caused by the shear stress produced by the flow of the viscous fluid. Our results and analysis indicate that the cochlea can sustain, without a significant CAP threshold shift, up to a 1.5 Pa shear stress. Beside these finding, in the 0.125% and 0.25% HA perfusion cases, a temporary CAP threshold shift was observed, perhaps due to the presence and

  8. Temperature controlled machine perfusion system for liver.

    PubMed

    Obara, H; Matsuno, N; Shigeta, T; Hirano, T; Enosawa, S; Mizunuma, H

    2013-06-01

    Organ preservation using machine perfusion is an effective method compared with conventional preservation techniques using static cold storage. A newly developed MP preservation system to control perfusate temperatures from hypothermic to subnormothermic conditions is introduced. This system is useful not only for liver preservation, but also for evaluation of graft viability for recovery. This novel method has been proposed for preservation of porcine liver grafts. An innovative preservation system is especially important to obtain viable organs from extended criteria or donation after cardiac death donors. In this study, we introduce a new machine perfusion preservation system (NES-01) to evaluate graft viability for recovery of liver functions, using porcine grafts.

  9. Correlation of CT perfusion and CT volumetry in patients with Alzheimer’s disease

    PubMed Central

    Czarnecka, Anna; Zimny, Anna; Sąsiadek, Marek

    2010-01-01

    Summary Background: Both brain atrophy and decrease of perfusion are observed in dementive diseases. The aim of the study was to correlate the results of brain perfusion CT (pCT) and CT volumetry in patients with Alzheimer’s disease (AD). Material/Methods: Forty-eight patients with AD (mean age of 71.3 years) underwent brain pCT and CT volumetry. The pCT was performed at the level of basal ganglia after the injection of contrast medium (50 ml, 4 ml/sec.) with serial scanning (delay 7 sec, 50 scans, 1 scan/sec). Volumetric measurements were carried out on the basis of source images, with the use of a dedicated CT software combined with manual outlining of the regions of interest in extracerebral and intraventricular CSF spaces. Perfusion parameters of the cerebral blood flow (CBF) and cerebral blood volume (CBV) from the grey matter of frontal and temporal as well as basal ganglia were compared statistically with the volumetric measurements of frontal and temporal cortical atrophy as well as subcortical atrophy. Results: A statistically significant positive correlation was found between the values of CBF and CBV in the basal ganglia and the volumes of the lateral and third ventricles. The comparison of CBF and CBV results with the volumetric measurements in the areas of the frontal and temporal lobes showed mostly negative correlations, but none of them was of statistical significance. Conclusions: In patients with AD, the degree of cortical atrophy is not correlated with the decrease of perfusion in the grey matter and subcortical atrophy is not correlated with the decrease of perfusion in the basal ganglia region. It suggests that functional and structural changes in AD are not related to each other. PMID:22802771

  10. Pulmonary Perfused Blood Volume with Dual-Energy CT as Surrogate for Pulmonary Perfusion Assessed with Dynamic Multidetector CT

    PubMed Central

    Fuld, Matthew K.; Halaweish, Ahmed F.; Haynes, Susan E.; Divekar, Abhay A.; Guo, Junfeng

    2013-01-01

    Purpose: To compare measurements of regional pulmonary perfused blood volume (PBV) and pulmonary blood flow (PBF) obtained with computed tomography (CT) in two pig models. Materials and Methods: The institutional animal care and use committee approved all animal studies. CT-derived PBF and PBV were determined in four anesthetized, mechanically ventilated, supine swine by using two methods for creating pulmonary parenchymal perfusion heterogeneity. Two animals were examined after sequentially moving a pulmonary arterial balloon catheter from a distal to a central location, and two others were examined over a range of static airway pressures, which varied the extents of regional PBF. Lung sections were divided into blocks and Pearson correlation coefficients calculated to compare matching regions between the two methods. Results: CT-derived PBF, CT-derived PBV, and their associated coefficients of variation (CV) were closely correlated on a region-by-region basis in both the balloon occlusion (Pearson R = 0.91 and 0.73 for animals 1 and 2, respectively; Pearson R = 0.98 and 0.87 for comparison of normalized mean and CV for animals 1 and 2, respectively) and lung inflation studies (Pearson R = 0.94 and 0.74 for animals 3 and 4, respectively; Pearson R = 0.94 and 0.69 for normalized mean and CV for animals 3 and 4, respectively). When accounting for region-based effects, correlations remained highly significant at the P < .001 level. Conclusion: CT-derived PBV heterogeneity is a suitable surrogate for CT-derived PBF heterogeneity. ©RSNA, 2012 Supplemental material: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12112789/-/DC1 PMID:23192773

  11. Cardiovascular magnetic resonance imaging of isolated perfused pig hearts in a 3T clinical MR scanner

    PubMed Central

    Chiribiri, Amedeo; Ishida, Masaki; Morton, Geraint; Paul, Matthias; Hussain, Shazia T.; Bigalke, Boris; Perera, Divaka; Schaeffter, Tobias; Nagel, Eike

    2012-01-01

    Purpose An isolated perfused pig heart model has recently been proposed for the development of novel methods in standard clinical magnetic resonance (MR) scanners. The original set-up required the electrical system to be within the safe part of the MR-room, which introduced significant background noise. The purpose of the current work was to refine the system to overcome this limitation so that all electrical parts are completely outside the scanner room. Methods Four pig hearts were explanted under terminal anaesthesia from large white cross landrace pigs. All hearts underwent cardiovascular magnetic resonance (CMR) scanning in the MR part of a novel combined 3T MR and x-ray fluoroscopy (XMR) suite. CMR scanning included real-time k-t SENSE functional imaging, k-t SENSE accelerated perfusion imaging and late gadolinium enhancement imaging. Interference with image quality was assessed by spurious echo imaging and compared to noise levels acquired while operating the electrical parts within the scanner room. Results Imaging was performed successfully in all hearts. The system proved suitable for isolated heart perfusion in a novel 3T XMR suite. No significant additional noise was introduced into the scanner room by our set-up. Conclusions We have substantially improved a previous version of an isolated perfused pig heart model and made it applicable for MR imaging in a state of the art clinical 3T XMR imaging suite. The use of this system should aid novel CMR sequence development and translation into clinical practice. PMID:24265875

  12. Effects of ammonium nitrate aerosol exposure on lung structure of normal and elastase-impaired rats and guinea pigs

    SciTech Connect

    Busch, R.H.; Buschbom, R.L.; Cannon, W.C.; Lauhala, K.E.; Miller, F.J.; Graham, J.A.; Smith, L.G.

    1986-04-01

    Groups of rats and guinea pigs with normal lungs and others with elastase-induced emphysema were exposed to NH/sub 4/NO/sub 3/ aerosols of 0.60 mass median aerodynamic diameter at 1 mg/m/sup 3/ for 6 hr/day, 5 days/week, for 4 weeks. Morphologic and morphometric studies were performed on lungs perfused with cacodylate-buffered 2% glutaraldehyde under 20 cm H/sub 2/O pressure at necropsy. The tissues were studied for pathologic change by light and electron microscopy; emphysema was evaluated by subgross and microscopic methods, including changes in mean alveolar chord length using scanning electron microscopy techniques. Elastase produced emphysema to a degree quantifiable by all criteria studied; however, it apparently obscured the effects of nitrate inhalation. The NH/sub 4/NO/sub 3/ exposure (compared to air alone) tended to increase values for pulmonary parameters in normal animals of both species and to decrease them in elastase-treated animals. The NH/sub 4/NO/sub 3/ exposure increased values for lung volume in rats, percentage area affected in elastase-treated rats, and chord length ..beta.. in normal animals of both species. The responses to NH/sub 4/NO/sub 3/ were slight and were not accompanied by any detectable changes in alveolar structure. Therefore, the effects of NH/sub 4/NO/sub 3/ at this exposure level and duration, are regarded as biologically insignificant for rats and guinea pigs.

  13. In-vivo regional myocardial perfusion measurements in a porcine model by ECG-gated multislice computed tomography

    NASA Astrophysics Data System (ADS)

    Stantz, Keith M.; Liang, Yun; Meyer, Cristopher A.; Teague, Shawn; Stecker, Michael; Hutchins, Gary; McLennan, Gordon; Persohn, Scott

    2003-05-01

    Purpose: To evaluate whether functional multi-slice computed tomography (MSCT) can identify regional areas of normally perfused and ischemic myocardium in a porcine model. Material and Methods: Three out bred pigs, two of which had ameroids surgically implanted to constrict flow within the LAD and LCx coronary arteries, were injected with 25 mL of iopromide (Isovue) at a rate of 5 mL/second via the femoral or jugular vein. Sixty axial scans along the short axis of the heart was acquired on a 16-slice CT scanner (Philips MX8000-IDT) triggered at end-diastole of the cardiac cycle and acquiring an image within 270 msec. A second series of scans were taken after an intravenous injection of a vasodilator, 150 μg/kg/min of adenosine. ROIs were drawn around the myocardial tissue and the resulting time-density curves were used to extract perfusion values. Results: Determination of the myocardial perfusion and fractional blood volume implementing three different perfusion models. A 5-point averaging or 'smoothing' algorithm was employed to effectively filter the data due to its noisy nature. The (preliminary) average perfusion and fractional blood volume values over selected axial slices for the pig without an artificially induced stenosis were measured to be 84 +/- 22 mL/min/100g-tissue and 0.17 +/- 0.04 mL/g-tissue, the former is consistent with PET scan and EBCT results. The pig with a stenosis in the left LAD coronary artery showed a reduced global perfusion value -- 45 mL/min/100g-tissue. Correlations in regional perfusion values relative to the stenosis were weak. During the infusion of adenosine, averaged perfusion values for the three subjects increased by 46 (+/-45) percent, comparable to increases measured with PET. Conclusion: Quantifying global perfusion values using MDCT appear encouraging. Future work will focus resolving the systematic effects from noise due to signal fluctuation from the porcine tachyardia (80-93 BPM) and provide a more robust measurement

  14. Microcirculation Perfusion Monitor on the Back of the Health Volunteers

    PubMed Central

    Li, Yanqi; Li, Xiaomei; Zhou, Dan; Wang, Kang; Liu, Yangyang; Guo, Yi; Qiu, Shuang; Zhai, Tianchen; Liu, Shuang; Liu, Jingjing; Ming, Dong

    2013-01-01

    Objective. To observe the dermal microcirculation blood perfusion characterization of meridians channels (acupoints). Methods. 20 healthy human subjects were monitored using Pericam Perfusion Speckle Imager (PSI) for the changes in dermal microcirculation blood perfusion on governor meridian and other respective dermal regions as a control. Result. The microcirculation blood perfusion on Governor Meridian is higher than its control area. Conclusion. The dermal microcirculation blood perfusion on certain parts of Governor Meridian of healthy human subjects showed specifics. PMID:24371463

  15. Luminal distension as a possible consequence of experimental intestinal perfusion

    PubMed Central

    Wingate, David; Hyams, Ashley; Phillips, Sidney

    1974-01-01

    In an experimental jejunal perfusion study, distress in healthy subjects occurred during eight out of 16 perfusions in which intestinal secretion was provoked. Calculation demonstrates the volumetric consequences of inadequate recovery of secretory perfusates, and analysis of the perfusion studies shows that distress was significantly associated with poor recovery of the perfusate. These observations are pertinent to increasing interest in the phenomenon of intestinal fluid secretion. PMID:4435588

  16. Pelvic CT scan

    MedlinePlus

    CAT scan - pelvis; Computed axial tomography scan - pelvis; Computed tomography scan - pelvis; CT scan - pelvis ... creates detailed pictures of the body, including the pelvis and areas near the pelvis. The test may ...

  17. Leg CT scan

    MedlinePlus

    CAT scan - leg; Computed axial tomography scan - leg; Computed tomography scan - leg; CT scan - leg ... on film. Three-dimensional (3D) models of the leg can be created by adding the slices together. ...

  18. Abscess scan - radioactive

    MedlinePlus

    Radioactive abscess scan; Abscess scan; Indium Scan; Indium-labelled white blood cell scan ... the white blood cells are tagged with a radioactive substance called indium. The cells are then injected ...

  19. Nonrespiratory metabolic function and morphology of lung following exposure to polybrominated biphenyls in rats

    SciTech Connect

    McCormack, K.M.; Roth, R.A.; Wallace, K.B.; Ross, L.M.; Hook, J.B.

    1982-01-01

    Exposure to polybrominated biphenyls (PBBs) resulted in increased activity of microsomal arylhydrocarbon hydroxylase and ethoxyresorufin-O-deethylase in rat lung. Clearance of 5-hydroxytryptamine (5-HT) and angiotensin I by perfused lungs was decreased by PBBs. However, PBBs had no effect on the activity of epoxide hydrolase, monoamine oxidase, or angiotensin-converting enzyme in lung. The only hisotpathlogic change detected in lungs from PBB-treated rats was an increase in alveolar type II cell lamellar bodies. Selective accumulation of certain PBB congeners by lung was not observed in this investigation.

  20. Novel approaches to expanding the lung donor pool: donation after cardiac death and ex vivo conditioning.

    PubMed

    Cypel, Marcelo; Yeung, Jonathan C; Keshavjee, Shaf

    2011-06-01

    Two novel approaches have been developed to potentially increase the availability of donor lungs for lung transplantation. In the first approach, lungs from donation after cardiac death (DCD) donors are used to increase the quantity of organ donors. In the second approach, a newly developed normothermic ex vivo lung perfusion (EVLP) technique is used as a means of reassessing the adequacy of lung function from DCD and from high-risk brain death donors prior to transplantation. This EVLP technique can also act as a platform for the delivery of novel therapies to repair injured organs ex vivo. PMID:21511086

  1. Noninvasive methods of measuring bone blood perfusion

    PubMed Central

    Dyke, J.P.; Aaron, R.K.

    2010-01-01

    Measurement of bone blood flow and perfusion characteristics in a noninvasive and serial manner would be advantageous in assessing revascularization after trauma and the possible risk of avascular necrosis. Many disease states, including osteoporosis, osteoarthritis, and bone neoplasms, result in disturbed bone perfusion. A causal link between bone perfusion and remodeling has shown its importance in sustained healing and regrowth following injury. Measurement of perfusion and permeability within the bone was performed with small and macromolecular contrast media, using dynamic contrast-enhanced magnetic resonance imaging in models of osteoarthritis and the femoral head. Bone blood flow and remodeling was estimated using 18F-Fluoride positron emission tomography in fracture healing and osteoarthritis. Multimodality assessment of bone blood flow, permeability, and remodeling by using noninvasive imaging techniques may provide information essential in monitoring subsequent rates of healing and response to treatment as well as identifying candidates for additional therapeutic or surgical interventions. PMID:20392223

  2. Bubble dynamics in perfused tissue undergoing decompression.

    PubMed

    Meisel, S; Nir, A; Kerem, D

    1981-02-01

    A mathematical model describing bubble dynamics in a perfused tissue undergoing decompression is presented, taking into account physical expansion and inward diffusion from surrounding supersaturated tissue as growth promoting factors and tissue gas elimination by perfusion, tissue elasticity, surface tension and inherent unsaturation as resolving driving forces. The expected behavior after a step reduction of pressure of a bubble initially existing in the tissue, displaying both growth and resolution has been demonstrated. A strong perfusion-dependence of bubble resolution time at low perfusion rates is apparent. The model can account for various exposure pressures and saturation fractions of any inert gas-tissue combination for which a set of physical and physiological parameters is available.

  3. Selected contribution: redistribution of pulmonary perfusion during weightlessness and increased gravity

    NASA Technical Reports Server (NTRS)

    Glenny, R. W.; Lamm, W. J.; Bernard, S. L.; An, D.; Chornuk, M.; Pool, S. L.; Wagner, W. W. Jr; Hlastala, M. P.; Robertson, H. T.

    2000-01-01

    To compare the relative contributions of gravity and vascular structure to the distribution of pulmonary blood flow, we flew with pigs on the National Aeronautics and Space Administration KC-135 aircraft. A series of parabolas created alternating weightlessness and 1.8-G conditions. Fluorescent microspheres of varying colors were injected into the pulmonary circulation to mark regional blood flow during different postural and gravitational conditions. The lungs were subsequently removed, air dried, and sectioned into approximately 2 cm(3) pieces. Flow to each piece was determined for the different conditions. Perfusion heterogeneity did not change significantly during weightlessness compared with normal and increased gravitational forces. Regional blood flow to each lung piece changed little despite alterations in posture and gravitational forces. With the use of multiple stepwise linear regression, the contributions of gravity and vascular structure to regional perfusion were separated. We conclude that both gravity and the geometry of the pulmonary vascular tree influence regional pulmonary blood flow. However, the structure of the vascular tree is the primary determinant of regional perfusion in these animals.

  4. Assessment of prognostic value of semiquantitative parameters on gated single photon emission computed tomography myocardial perfusion scintigraphy in a large middle eastern population

    PubMed Central

    Chavoshi, Maryam; Fard-Esfahani, Armaghan; Fallahi, Babak; Emami-Ardekani, Alireza; Beiki, Davood; Hassanzadeh-Rad, Arman; Eftekhari, Mohammad

    2015-01-01

    Objectives: Coronary artery disease is the leading cause of mortality worldwide. The goal of this study is to determine the prognostic value of semiquantitative parameters of electrocardiogram-gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) in a large Middle Eastern (Iranian) population. Materials and Methods: This study was a prospective study including all patients referred to our center for myocardial perfusion scan. The patients were followed annually up to 24 months and their survival information was collected. Results: From 1148 patients, 473 (41.2%) men and 675 (58.8%) women, 40.6% had normal MPI, 13.3% near normal and 46.1% abnormal MPI. After follow-up of 929 patients, 97.4% of patients were alive, and 2.6% succumbed to cardiac deaths. Abnormal ejection fraction was related with cardiac events (P = 0.001), but neither transient ischemic dilation (TID) (P = 0.09) nor lung/heart ratio (P = 0.92) showed such relationship. Association between summed difference score (SDS) and soft cardiac events (P < 0.001) was significant. Summed motion score (SMS) and summed thickening score (STS) showed a significant relation with hard cardiac events, including myocardial infarction and cardiac death (P < 0.001 and P = 0.001, respectively). Totally, risk of all cardiac events was significantly higher in abnormal MPI group than normal group (P < 0.001, 0.02, and 0.025, respectively). No significant relationship was found between TID and total cardiac events (P = 0.478). Conclusion: Semiquantitative variables derived from gated SPECT MPI have independent prognostic value. Rate of total cardiac events is higher in patients with higher summed stress score and SDS. Total and hard cardiac events are higher in upper scores of functional parameters (SMS and STS). Total cardiac events are higher in patients with lower left ventricular ejection fraction. PMID:26170566

  5. Vicarious Audiovisual Learning in Perfusion Education

    PubMed Central

    Rath, Thomas E.; Holt, David W.

    2010-01-01

    Abstract: Perfusion technology is a mechanical and visual science traditionally taught with didactic instruction combined with clinical experience. It is difficult to provide perfusion students the opportunity to experience difficult clinical situations, set up complex perfusion equipment, or observe corrective measures taken during catastrophic events because of patient safety concerns. Although high fidelity simulators offer exciting opportunities for future perfusion training, we explore the use of a less costly low fidelity form of simulation instruction, vicarious audiovisual learning. Two low fidelity modes of instruction; description with text and a vicarious, first person audiovisual production depicting the same content were compared. Students (n = 37) sampled from five North American perfusion schools were prospectively randomized to one of two online learning modules, text or video. These modules described the setup and operation of the MAQUET ROTAFLOW standalone centrifugal console and pump. Using a 10 question multiple-choice test, students were assessed immediately after viewing the module (test #1) and then again 2 weeks later (test #2) to determine cognition and recall of the module content. In addition, students completed a questionnaire assessing the learning preferences of today’s perfusion student. Mean test scores from test #1 for video learners (n = 18) were significantly higher (88.89%) than for text learners (n = 19) (74.74%), (p < .05). The same was true for test #2 where video learners (n = 10) had an average score of 77% while text learners (n = 9) scored 60% (p < .05). Survey results indicated video learners were more satisfied with their learning module than text learners. Vicarious audiovisual learning modules may be an efficacious, low cost means of delivering perfusion training on subjects such as equipment setup and operation. Video learning appears to improve cognition and retention of learned content and may play an important

  6. Pancreas transplants: Evaluation using perfusion scintigraphy

    SciTech Connect

    Kuni, C.C.; du Cret, R.P.; Boudreau, R.J.

    1989-07-01

    To determine the value of scintigraphic perfusion studies in evaluating pancreas transplant patients, we reviewed 56 of these studies in 22 patients who had 27 transplants. Seventeen patients underwent two or more studies. The perfusion studies were performed with 20 mCi (740 MBq) of 99mTc-DTPA injected as a bolus followed by eight to 16 serial 2-sec images and a 500,000-count immediate static image. Images were evaluated for (1) the time and intensity of pancreatic peak radioactivity relative to the time and intensity of the iliac arterial peak; (2) relative pancreatic to iliac arterial intensity on the static image; and (3) size, homogeneity, and definition of the pancreas. Clinical diagnoses at the time of scintigraphy of normal function (n = 36), rejection (n = 13), pancreatitis (n = 6), or arterial thrombosis (n = 1) were based on insulin requirement, urine amylase, serum glucose, serum amylase, response to therapy, cultures, CT, MR, sonography, scintigraphy with 67Ga or 111In-WBCs, percutaneous drainage results, angiography, surgery, and pathologic examination of resected transplants. Three 99mTc-DTPA perfusion studies showed no pancreatic perfusion, four showed decreasing perfusion on serial studies, and five showed progressive loss of definition of the pancreas on serial studies. Of the three patients with no detectable perfusion, one had a normally functioning transplant, one had arterial thrombosis with transplant infarction, and one had severe rejection with minimal function. Decreasing perfusion was associated with rejection in three patients and pancreatitis in one. Decreasing definition was seen in four patients with rejection and one with pancreatitis. We conclude that perfusion scintigraphy is useful, primarily when performed serially, although nonspecific for evaluating pancreas transplants.

  7. Improved exercise myocardial perfusion during lidoflazine therapy

    SciTech Connect

    Shapiro, W.; Narahara, K.A.; Park, J.

    1983-11-01

    Lidoflazine is a synthetic drug with calcium-channel blocking effects. In a study of 6 patients with severe classic angina pectoris, single-blind administration of lidoflazine was associated with improved myocardial perfusion during exercise as determined by thallium-201 stress scintigraphy. These studies demonstrate that lidoflazine therapy is associated with relief of angina, an increased physical work capacity, and improved regional myocardial perfusion during exercise.

  8. Effects of pulmonary ischemia on lung morphology.

    PubMed

    Fields, Michael J; Bishai, John M; Mitzner, Wayne; Wagner, Elizabeth M

    2007-07-01

    Pulmonary ischemia resulting from chronic pulmonary embolism leads to proliferation of the systemic circulation within and surrounding the lung. However, it is not clear how well alveolar tissue is sustained during the time of complete pulmonary ischemia. In the present study, we investigated how pulmonary ischemia after left pulmonary artery ligation (LPAL) would alter lung mechanical properties and morphology. In this established mouse model of lung angiogenesis after chronic LPAL (10), we evaluated lung function and structure before (3 days) and after (14 days) a functional systemic circulation to the left lung is established. Age-matched naïve and sham-operated C57Bl/6 mice and mice undergoing chronic LPAL were studied. Left and right lung pressure-volume relationships were determined. Next, lungs were inflated in situ with warmed agarose (25-30 cmH(2)O) and fixed, and mean chord lengths (MCL) of histological sections were quantified. MCL of naïve mice averaged 43.9 +/- 1.8 mum. No significant changes in MCL were observed at either time point after LPAL. Left lung volumes and specific compliances were significantly reduced 3 days after LPAL. However, by 14 days after LPAL, lung pressure-volume relationships were not different from controls. These results suggest that severe pulmonary ischemia causes changes in lung mechanics early after LPAL that are reversed by the time a new systemic vasculature is known to perfuse pulmonary capillaries. The LPAL model thus affords a unique opportunity to study lung functional responses to tissue ischemia and subsequent recovery. PMID:17449796

  9. Lung physiology and aerosol deposition imaged with positron emission tomography.

    PubMed

    Venegas, Jose; Winkler, Tilo; Harris, R Scott

    2013-02-01

    Physiological conditions and pathophysiological changes in the lungs may affect many applications in aerosol medicine and pulmonary drug delivery. In the diseased lung, spatial heterogeneity in function and structure may cause substantial changes in aerosol transport and local deposition among different lung regions. Non-uniform aerosol deposition affects airway or tissue pharmacological dosing, which could reduce the therapeutic effectiveness of inhalation therapy. This review article presents examples of pulmonary imaging using PET and PET-CT in lung physiology with an emphasis on their implications for aerosol medicine. Measurements of regional ventilation, perfusion, and ventilation/perfusion ratio, by imaging local kinetics of intravenously injected Nitrogen-13 in saline solution, and of pulmonary inflammation, by assessing the regional uptake of the radiotracer (18)F-FDG, are presented. These examples demonstrate that it is possible to access both preexisting conditions, such as heterogeneity of ventilation, perfusion, and/or inflammatory stimuli, which may affect inhalation therapy, and the functional effects of inhaled medications or inflammatory agents on lung regional function. The imaging techniques described could be efficient tools to evaluate quantitatively and noninvasively these processes in vivo. Furthermore, it can be expected that imaging of respiratory structure and function will yield sensitive biomarkers of disease, which will help and speed drug discovery, and the evaluation of novel inhalation therapies.

  10. C5-derived activity is required for complement neutrophil-mediated lung injury

    SciTech Connect

    Morganroth, M.L.; Till, G.O.; Ward, P.A.

    1986-03-05

    Cobra venom factor (CVF) derived from the cobra species Naja naja (NN) is a complement activator (cleaves C3, C5 and terminal components) which causes neutrophil dependent acute lung injury and pulmonary hypertension in rats. CVF, derived from the cobra species Naja haje (NH), differs from NN-CVF in that only C3 is cleaved. The authors investigated in isolated blood perfused rat lungs if NH-CVF (n=5), a complement activator which does not generate C5 derived peptides, causes pulmonary hypertension and acute lung injury. NN-CVF (n=5) caused a transient increase in mean pulmonary artery pressure (PA) which returned toward baseline by 30 min (Peak ..delta.. PA = 17 +/- 6 mmHg). Lung injury occurred and was quantitated by the leak of /sup 125/I bovine serum albumin (/sup 125/I-BSA added 30 min post CVF) into lung parenchyma (lung/perfusate /sup 125/I-BSA counts: control = .09 +/- .01, NN-CVF = .48 +/- .11, p < .05). NH-CVF, in an amount which caused equipotent in vitro hemolysis of nonsensitized rabbit erythrocytes, did not cause a PA pressor response (3.5 +/- 1.1 mm Hg, p=NS) or acute lung injury (lung/perfusate /sup 125/I-BSA counts .11 +/- .01, p=NS). Similarly, NH-CVF did not appear to cause lung injury in intact rats (lung perfusate /sup 125/I-BSA counts: control .20 +/- .01, n=3; NH-CVF .25 +/- .05, n=3; NN-CVF .83 +/- .27, n=2). Thus, C3 cleavage alone without the generation of C5 derived peptides is an inadequate stimulus to elicit neutrophil-mediated acute lung injury.

  11. Lung transplantation

    PubMed Central

    Afonso, José Eduardo; Werebe, Eduardo de Campos; Carraro, Rafael Medeiros; Teixeira, Ricardo Henrique de Oliveira Braga; Fernandes, Lucas Matos; Abdalla, Luis Gustavo; Samano, Marcos Naoyuki; Pêgo-Fernandes, Paulo Manuel

    2015-01-01

    ABSTRACT Lung transplantation is a globally accepted treatment for some advanced lung diseases, giving the recipients longer survival and better quality of life. Since the first transplant successfully performed in 1983, more than 40 thousand transplants have been performed worldwide. Of these, about seven hundred were in Brazil. However, survival of the transplant is less than desired, with a high mortality rate related to primary graft dysfunction, infection, and chronic graft dysfunction, particularly in the form of bronchiolitis obliterans syndrome. New technologies have been developed to improve the various stages of lung transplant. To increase the supply of lungs, ex vivo lung reconditioning has been used in some countries, including Brazil. For advanced life support in the perioperative period, extracorporeal membrane oxygenation and hemodynamic support equipment have been used as a bridge to transplant in critically ill patients on the waiting list, and to keep patients alive until resolution of the primary dysfunction after graft transplant. There are patients requiring lung transplant in Brazil who do not even come to the point of being referred to a transplant center because there are only seven such centers active in the country. It is urgent to create new centers capable of performing lung transplantation to provide patients with some advanced forms of lung disease a chance to live longer and with better quality of life. PMID:26154550

  12. Lung Diseases

    MedlinePlus

    When you breathe, your lungs take in oxygen from the air and deliver it to the bloodstream. The cells in your body need oxygen to ... you breathe nearly 25,000 times. People with lung disease have difficulty breathing. Millions of people in ...

  13. Lung Cancer

    MedlinePlus

    Lung cancer is one of the most common cancers in the world. It is a leading cause of cancer death in men and women in the United States. Cigarette smoking causes most lung cancers. The more cigarettes you smoke per day and ...

  14. Technical aspects of MR perfusion.

    PubMed

    Sourbron, Steven

    2010-12-01

    The most common methods for measuring perfusion with MRI are arterial spin labelling (ASL), dynamic susceptibility contrast (DSC-MRI), and T(1)-weighted dynamic contrast enhancement (DCE-MRI). This review focuses on the latter approach, which is by far the most common in the body and produces measures of capillary permeability as well. The aim is to present a concise but complete overview of the technical issues involved in DCE-MRI data acquisition and analysis. For details the reader is referred to the references. The presentation of the topic is essentially generic and focuses on technical aspects that are common to all DCE-MRI measurements. For organ-specific problems and illustrations, we refer to the other papers in this issue. In Section 1 "Theory" the basic quantities are defined, and the physical mechanisms are presented that provide a relation between the hemodynamic parameters and the DCE-MRI signal. Section 2 "Data acquisition" discusses the issues involved in the design of an optimal measurement protocol. Section 3 "Data analysis" summarizes the steps that need to be taken to determine the hemodynamic parameters from the measured data. PMID:20363574

  15. Simultaneous Myocardial Strain and Dark-Blood Perfusion Imaging Using a Displacement-Encoded MRI Pulse Sequence

    PubMed Central

    Le, Yuan; Stein, Ashley; Berry, Colin; Kellman, Peter; Bennett, Eric E.; Taylor, Joni; Lucas, Katherine; Kopace, Rael; Chefd’Hotel, Christophe; Lorenz, Christine H.; Croisille, Pierre; Wen, Han

    2010-01-01

    The purpose of this study is to develop and evaluate a displacement-encoded pulse sequence for simultaneous perfusion and strain imaging. Displacement-encoded images in 2–3 myocardial slices were repeatedly acquired using a single shot pulse sequence for 3 to 4 minutes, which covers a bolus infusion of Gd. The magnitudes of the images were T1 weighted and provided quantitative measures of perfusion, while the phase maps yielded strain measurements. In an acute coronary occlusion swine protocol (n=9), segmental perfusion measurements were validated against microsphere reference standard with a linear regression (slope 0.986, R2 = 0.765, Bland-Altman standard deviation = 0.15 ml/min/g). In a group of ST-elevation myocardial infarction(STEMI) patients (n=11), the scan success rate was 76%. Short-term contrast washout rate and perfusion are highly correlated (R2=0.72), and the pixel-wise relationship between circumferential strain and perfusion was better described with a sigmoidal Hill curve than linear functions. This study demonstrates the feasibility of measuring strain and perfusion from a single set of images. PMID:20544714

  16. Simultaneous myocardial strain and dark-blood perfusion imaging using a displacement-encoded MRI pulse sequence.

    PubMed

    Le, Yuan; Stein, Ashley; Berry, Colin; Kellman, Peter; Bennett, Eric E; Taylor, Joni; Lucas, Katherine; Kopace, Rael; Chefd'Hotel, Christophe; Lorenz, Christine H; Croisille, Pierre; Wen, Han

    2010-09-01

    The purpose of this study is to develop and evaluate a displacement-encoded pulse sequence for simultaneous perfusion and strain imaging. Displacement-encoded images in two to three myocardial slices were repeatedly acquired using a single-shot pulse sequence for 3 to 4 min, which covers a bolus infusion of Gadolinium contrast. The magnitudes of the images were T(1) weighted and provided quantitative measures of perfusion, while the phase maps yielded strain measurements. In an acute coronary occlusion swine protocol (n = 9), segmental perfusion measurements were validated against microsphere reference standard with a linear regression (slope 0.986, R(2) = 0.765, Bland-Altman standard deviation = 0.15 mL/min/g). In a group of ST-elevation myocardial infarction patients (n = 11), the scan success rate was 76%. Short-term contrast washout rate and perfusion are highly correlated (R(2) = 0.72), and the pixelwise relationship between circumferential strain and perfusion was better described with a sigmoidal Hill curve than linear functions. This study demonstrates the feasibility of measuring strain and perfusion from a single set of images. PMID:20544714

  17. Lung diffusion testing

    MedlinePlus

    Lung diffusion testing measures how well the lungs exchange gases. This is an important part of lung testing , because ... gases do not move normally across the lung tissues into the blood vessels of the lung. This ...

  18. Collapsed lung (pneumothorax)

    MedlinePlus

    Air around the lung; Air outside the lung; Pneumothorax dropped lung; Spontaneous pneumothorax ... Collapsed lung can be caused by an injury to the lung. Injuries can include a gunshot or knife wound ...

  19. Lung disease - resources

    MedlinePlus

    Resources - lung disease ... The following organizations are good resources for information on lung disease : American Lung Association -- www.lung.org National Heart, Lung, and Blood Institute -- www.nhlbi.nih.gov ...

  20. SU-E-J-266: Cone Beam Computed Tomography (CBCT) Inter-Scan and Inter-Observer Tumor Volume Variability Assessment in Patients Treated with Stereotactic Body Radiation Therapy (SBRT) for Early Stage Non-Small Cell Lung Cancer (NSCLC)

    SciTech Connect

    Hou, Y; Aileen, C; Kozono, D; Killoran, J; Wagar, M; Lee, S; Hacker, F; Aerts, H; Lewis, J; Mak, R

    2015-06-15

    Purpose: Quantification of volume changes on CBCT during SBRT for NSCLC may provide a useful radiological marker for radiation response and adaptive treatment planning, but the reproducibility of CBCT volume delineation is a concern. This study is to quantify inter-scan/inter-observer variability in tumor volume delineation on CBCT. Methods: Twenty earlystage (stage I and II) NSCLC patients were included in this analysis. All patients were treated with SBRT with a median dose of 54 Gy in 3 to 5 fractions. Two physicians independently manually contoured the primary gross tumor volume on CBCTs taken immediately before SBRT treatment (Pre) and after the same SBRT treatment (Post). Absolute volume differences (AVD) were calculated between the Pre and Post CBCTs for a given treatment to quantify inter-scan variability, and then between the two observers for a given CBCT to quantify inter-observer variability. AVD was also normalized with respect to average volume to obtain relative volume differences (RVD). Bland-Altman approach was used to evaluate variability. All statistics were calculated with SAS version 9.4. Results: The 95% limit of agreement (mean ± 2SD) on AVD and RVD measurements between Pre and Post scans were −0.32cc to 0.32cc and −0.5% to 0.5% versus −1.9 cc to 1.8 cc and −15.9% to 15.3% for the two observers respectively. The 95% limit of agreement of AVD and RVD between the two observers were −3.3 cc to 2.3 cc and −42.4% to 28.2% respectively. The greatest variability in inter-scan RVD was observed with very small tumors (< 5 cc). Conclusion: Inter-scan variability in RVD is greatest with small tumors. Inter-observer variability was larger than inter-scan variability. The 95% limit of agreement for inter-observer and inter-scan variability (∼15–30%) helps define a threshold for clinically meaningful change in tumor volume to assess SBRT response, with larger thresholds needed for very small tumors. Part of the work was funded by a Kaye

  1. Scintigraphic determination of ventricular function and coronary perfusion in long-distance runners

    SciTech Connect

    Osbakken, M.; Locko, R.

    1984-08-01

    Left ventricular function and coronary perfusion were evaluated with rest-exercise gated blood pool and stress-redistribution thallium scans in a group of long-distance runners and compared to a group of catheterization-proved normal subjects. Exercise duration, work load, and oxygen consumption were significantly greater for long-distance runners. Rest end-diastolic volume (EDV), end-systolic volume (ESV), and stroke volumes (SV) were significantly larger in long-distance runners than in control subjects, while ejection fraction (EF), cardiac index (CI), and ejection rate were similar in both groups. Exercise EDV increased and ESV decreased, producing an increase in SV and EF in long-distance runners. Exercise EDV did not change and ESV decreased less, producing lesser increase in SV and EF in the control group. Qualitative evaluation of thallium scans showed apparent perfusion defects with normal redistribution in six myocardial segments in five long-distance runners. Quantitative evaluation demonstrated initial defects, which persisted on delay scans, but were associated with normal relative redistribution in three ventricular walls in three long-distance runners. In conclusion, left ventricular reserve function was greater in long-distance runners than in control subjects. Endurance exercise can be associated with apparent myocardial perfusion defects, which may be due to uneven ventricular hypertrophy resulting from the pressure and volume loads imposed by exercise.

  2. Perfusion Neuroimaging Abnormalities Alone Distinguish National Football League Players from a Healthy Population

    PubMed Central

    Amen, Daniel G.; Willeumier, Kristen; Omalu, Bennet; Newberg, Andrew; Raghavendra, Cauligi; Raji, Cyrus A.

    2016-01-01

    Background: National Football League (NFL) players are exposed to multiple head collisions during their careers. Increasing awareness of the adverse long-term effects of repetitive head trauma has raised substantial concern among players, medical professionals, and the general public. Objective: To determine whether low perfusion in specific brain regions on neuroimaging can accurately separate professional football players from healthy controls. Method: A cohort of retired and current NFL players (n = 161) were recruited in a longitudinal study starting in 2009 with ongoing interval follow up. A healthy control group (n = 124) was separately recruited for comparison. Assessments included medical examinations, neuropsychological tests, and perfusion neuroimaging with single photon emission computed tomography (SPECT). Perfusion estimates of each scan were quantified using a standard atlas. We hypothesized that hypoperfusion particularly in the orbital frontal, anterior cingulate, anterior temporal, hippocampal, amygdala, insular, caudate, superior/mid occipital, and cerebellar sub-regions alone would reliably separate controls from NFL players. Cerebral perfusion differences were calculated using a one-way ANOVA and diagnostic separation was determined with discriminant and automatic linear regression predictive models. Results: NFL players showed lower cerebral perfusion on average (p < 0.01) in 36 brain regions. The discriminant analysis subsequently distinguished NFL players from controls with 90% sensitivity, 86% specificity, and 94% accuracy (95% CI 95-99). Automatic linear modeling achieved similar results. Inclusion of age and clinical co-morbidities did not improve diagnostic classification. Conclusion: Specific brain regions commonly damaged in traumatic brain injury show abnormally low perfusion on SPECT in professional NFL players. These same regions alone can distinguish this group from healthy subjects with high diagnostic accuracy. This

  3. Effects of Steroid Hormones on Sex Differences in Cerebral Perfusion.

    PubMed

    Ghisleni, Carmen; Bollmann, Steffen; Biason-Lauber, Anna; Poil, Simon-Shlomo; Brandeis, Daniel; Martin, Ernst; Michels, Lars; Hersberger, Martin; Suckling, John; Klaver, Peter; O'Gorman, Ruth L

    2015-01-01

    Sex differences in the brain appear to play an important role in the prevalence and progression of various neuropsychiatric disorders, but to date little is known about the cerebral mechanisms underlying these differences. One widely reported finding is that women demonstrate higher cerebral perfusion than men, but the underlying cause of this difference in perfusion is not known. This study investigated the putative role of steroid hormones such as oestradiol, testosterone, and dehydroepiandrosterone sulphate (DHEAS) as underlying factors influencing cerebral perfusion. We acquired arterial spin labelling perfusion images of 36 healthy adult subjects (16 men, 20 women). Analyses on average whole brain perfusion levels included a multiple regression analysis to test for the relative impact of each hormone on the global perfusion. Additionally, voxel-based analyses were performed to investigate the sex difference in regional perfusion as well as the correlations between local perfusion and serum oestradiol, testosterone, and DHEAS concentrations. Our results replicated the known sex difference in perfusion, with women showing significantly higher global and regional perfusion. For the global perfusion, DHEAS was the only significant predictor amongst the steroid hormones, showing a strong negative correlation with cerebral perfusion. The voxel-based analyses revealed modest sex-dependent correlations between local perfusion and testosterone, in addition to a strong modulatory effect of DHEAS in cortical, subcortical, and cerebellar regions. We conclude that DHEAS in particular may play an important role as an underlying factor driving the difference in cerebral perfusion between men and women.

  4. Subclinical Interstitial Lung Disease

    PubMed Central

    Doyle, Tracy J.; Hunninghake, Gary M.

    2012-01-01

    The widespread use of high-resolution computed tomography in clinical and research settings has increased the detection of interstitial lung abnormalities (ILA) in asymptomatic and undiagnosed individuals. We reported that in smokers, ILA were present in about 1 of every 12 high-resolution computed tomographic scans; however, the long-term significance of these subclinical changes remains unclear. Studies in families affected with pulmonary fibrosis, smokers with chronic obstructive pulmonary disease, and patients with inflammatory lung disease have shown that asymptomatic and undiagnosed individuals with ILA have reductions in lung volume, functional limitations, increased pulmonary symptoms, histopathologic changes, and molecular profiles similar to those observed in patients with clinically significant interstitial lung disease (ILD). These findings suggest that, in select at-risk populations, ILA may represent early stages of pulmonary fibrosis or subclinical ILD. The growing interest surrounding this topic is motivated by our poor understanding of the inciting events and natural history of ILD, coupled with a lack of effective therapies. In this perspective, we outline past and current research focused on validating radiologic, physiological, and molecular methods to detect subclinical ILD. We discuss the limitations of the available cross-sectional studies and the need for future longitudinal studies to determine the prognostic and therapeutic implications of subclinical ILD in populations at risk of developing clinically significant ILD. PMID:22366047

  5. Excitation-scanning hyperspectral imaging microscope.

    PubMed

    Favreau, Peter F; Hernandez, Clarissa; Heaster, Tiffany; Alvarez, Diego F; Rich, Thomas C; Prabhat, Prashant; Leavesley, Silas J

    2014-04-01

    Hyperspectral imaging is a versatile tool that has recently been applied to a variety of biomedical applications, notably live-cell and whole-tissue signaling. Traditional hyperspectral imaging approaches filter the fluorescence emission over a broad wavelength range while exciting at a single band. However, these emission-scanning approaches have shown reduced sensitivity due to light attenuation from spectral filtering. Consequently, emission scanning has limited applicability for time-sensitive studies and photosensitive applications. In this work, we have developed an excitation-scanning hyperspectral imaging microscope that overcomes these limitations by providing high transmission with short acquisition times. This is achieved by filtering the fluorescence excitation rather than the emission. We tested the efficacy of the excitation-scanning microscope in a side-by-side comparison with emission scanning for detection of green fluorescent protein (GFP)-expressing endothelial cells in highly autofluorescent lung tissue. Excitation scanning provided higher signal-to-noise characteristics, as well as shorter acquisition times (300  ms/wavelength band with excitation scanning versus 3  s/wavelength band with emission scanning). Excitation scanning also provided higher delineation of nuclear and cell borders, and increased identification of GFP regions in highly autofluorescent tissue. These results demonstrate excitation scanning has utility in a wide range of time-dependent and photosensitive applications. PMID:24727909

  6. Excitation-scanning hyperspectral imaging microscope

    PubMed Central

    Favreau, Peter F.; Hernandez, Clarissa; Heaster, Tiffany; Alvarez, Diego F.; Rich, Thomas C.; Prabhat, Prashant; Leavesley, Silas J.

    2014-01-01

    Abstract. Hyperspectral imaging is a versatile tool that has recently been applied to a variety of biomedical applications, notably live-cell and whole-tissue signaling. Traditional hyperspectral imaging approaches filter the fluorescence emission over a broad wavelength range while exciting at a single band. However, these emission-scanning approaches have shown reduced sensitivity due to light attenuation from spectral filtering. Consequently, emission scanning has limited applicability for time-sensitive studies and photosensitive applications. In this work, we have developed an excitation-scanning hyperspectral imaging microscope that overcomes these limitations by providing high transmission with short acquisition times. This is achieved by filtering the fluorescence excitation rather than the emission. We tested the efficacy of the excitation-scanning microscope in a side-by-side comparison with emission scanning for detection of green fluorescent protein (GFP)-expressing endothelial cells in highly autofluorescent lung tissue. Excitation scanning provided higher signal-to-noise characteristics, as well as shorter acquisition times (300  ms/wavelength band with excitation scanning versus 3  s/wavelength band with emission scanning). Excitation scanning also provided higher delineation of nuclear and cell borders, and increased identification of GFP regions in highly autofluorescent tissue. These results demonstrate excitation scanning has utility in a wide range of time-dependent and photosensitive applications. PMID:24727909

  7. Early detection of lung cancer

    PubMed Central

    Midthun, David E.

    2016-01-01

    Most patients with lung cancer are diagnosed when they present with symptoms, they have advanced stage disease, and curative treatment is no longer an option. An effective screening test has long been desired for early detection with the goal of reducing mortality from lung cancer. Sputum cytology, chest radiography, and computed tomography (CT) scan have been studied as potential screening tests. The National Lung Screening Trial (NLST) demonstrated a 20% reduction in mortality with low-dose CT (LDCT) screening, and guidelines now endorse annual LDCT for those at high risk. Implementation of screening is underway with the desire that the benefits be seen in clinical practice outside of a research study format. Concerns include management of false positives, cost, incidental findings, radiation exposure, and overdiagnosis. Studies continue to evaluate LDCT screening and use of biomarkers in risk assessment and diagnosis in attempt to further improve outcomes for patients with lung cancer. PMID:27158468

  8. Medical imaging in lung cancer

    SciTech Connect

    Heelan, R.T.; Bains, M.S.; Yeh, S.

    1987-10-01

    The routine imaging work-up of suspected lung cancer should include posteroanterior and lateral chest radiographs and, in most cases, a computed tomographic (CT) scan of the entire thorax and adrenal glands. In asymptomatic patients with adenocarcinoma of the lung, there is justification for doing routine contrast-enhanced CT examination of the brain. Further imaging workup will be suggested by the patient's history, physical findings, and laboratory findings. Magnetic resonance imaging of the chest in patients with lung cancer is being investigated, but current studies comparing it with CT demonstrate no definite advantage at this time, with the possible exception of the lung apex in which T1 weighted thin-section coronal views are useful.

  9. Partial volume correction of brain perfusion estimates using the inherent signal data of time-resolved arterial spin labeling.

    PubMed

    Ahlgren, André; Wirestam, Ronnie;