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Sample records for perfusion lung scan

  1. Lung Ventilation/Perfusion Scan

    MedlinePlus

    ... Scan Lung VQ Scan Related Topics Arrhythmia Cough Deep Vein Thrombosis Pulmonary Embolism Send a link to NHLBI to someone by ... this topic. Related reading Chest X Ray Cough Deep Vein Thrombosis Pulmonary Embolism Rate This Content: Updated: December 9, 2016 Twitter ...

  2. Lung Perfusion Scanning in Hepatic Cirrhosis

    PubMed Central

    Stanley, N. N.; Ackrill, P.; Wood, J.

    1972-01-01

    Abnormal lung perfusion scans using radioactive particles were found in five out of six cases of hepatic cirrhosis with arterial hypoxaemia. None had clinical evidence of cardiopulmonary disease or signs of pulmonary embolism on arteriography. The scan defects are probably caused by a disorder of the pulmonary microvasculature, which may show regional variation in severity. ImagesFIG. 1FIG. 2 PMID:4645896

  3. The low specificity of postoperative perfusion lung scan defects.

    PubMed Central

    Walker, I; Aukland, P; Hirsh, J; Coates, G; Cockshott, P; Taylor, R; Hull, R

    1981-01-01

    Ventilation and perfusion lung scans were performed preoperatively and postoperatively in 169 patients and classified blindly according to preset criteria. Perfusion lung scan abnormalities were present in 25 (15%) of the preoperative scans and 42 (25%) of the postoperative scans; 16 (38%) of the 42 abnormal postoperative scans were identical to the preoperative scans. Perfusion defects indicating a "high probability" of pulmonary embolism (lobar or segmental defects) were present in 5 preoperative scans and 10 postoperative scans; the 10 postoperative scans were classified as showing "definite" (5), "possible" (1) or "no" (4) pulmonary embolism on the basis of the preoperative scan and the ventilation scan; none of the 10 patients had clinical evidence of pulmonary embolism. Venous thrombosis was present in 12 patients, including 4 of the patients whose lung scans showed definite pulmonary embolism. Thus, postoperative perfusion lung scan defects are potentially misleading even when large. PMID:7459778

  4. Perfusion lung scanning: differentiation of primary from thromboembolic pulmonary hypertension

    SciTech Connect

    Lisbona, R.; Kreisman, H.; Novales-Diaz, J.; Derbekyan, V.

    1985-01-01

    Of eight patients with pulmonary arterial hypertension, final diagnosis established by autopsy or angiography, four had primary hypertension and four hypertension from thromboembolism. The perfusion lung scan was distinctly different in the two groups. The lung scan in primary pulmonary hypertension was associated with nonsegmental, patchy defects of perfusion, while in thromboembolic hypertensives it was characterized by segmental and/or lobar defects of perfusion with or without subsegmental defects. The perfusion lung scan is a valuable, noninvasive study in the evaluation of the patient with pulmonary hypertension of undetermined cause and in the exclusion of occult large-vessel pulmonary thromboembolism.

  5. Perfusion lung scan: an aid in detection of lymphangitic carcinomatosis

    SciTech Connect

    Bates, S.E.; Tranum, B.L.

    1982-07-15

    Lymphangitic carcinomatosis is usually a late manifestation of metastatic disease. The patient usually presents with cough or dyspnea, and the chest radiograph is often nondiagnostic. Two patients are presented who developed symptoms while on adjuvant chemotherapy. Both had abnormal perfusion lung scans. One had matching ventilation defects; the other a normal ventilation study. Biopsy revealed metastatic carcinoma; in one case tumor was seen in both the pulmonary lymphatics and arterioles; in the other, tumor was identified but the site could not be specified. The radionuclide lung scan is a technique which can speed diagnosis and institution of therapy in lymphangitic carcinomatosis.

  6. Perfusion lung scan: an aid in detection of lymphangitic carcinomatosis

    SciTech Connect

    Bates, S.E.; Tranum, B.L.

    1982-07-15

    Lymphangitic carcinomatosis is usually a late manifestation of metastatic disease. The patient usually presents with cough or dyspnea, and the chest radiograph is often nondiagnostic. Two patients are presented who developed symptoms while on adjuvant chemotherapy. Both had abnormal perfusion lung scans. One had matching ventilation defects; the other a normal ventilation study. Biopsy revealed metastatic carcinoma; in one case tumor was seen in both the pulmonary lymphatics and arterioles; in technique which can speed diagnosis and institution of therapy in lymphangitic carcinomatosis.

  7. Evaluation of Primary Pulmonary Vein Stenosis in Children: Comparison of Radionuclide Perfusion Lung Scan and Angiography.

    PubMed

    Drubach, Laura A; Jenkins, Kathy J; Stamoulis, Catherine; Palmer, Edwin L; Lee, Edward Y

    2015-10-01

    The purpose of this study was to evaluate the utility of radionuclide perfusion lung scanning in the evaluation of primary pulmonary vein stenosis (PVS) in pediatric patients by comparing it with angiography. We retrospectively identified pediatric patients with primary PVS who underwent both lung scanning and angiography. A cohort of 34 patients was evaluated. The presence of PVS in the right upper, right lower, left upper, and left lower pulmonary veins on angiograms was recorded. Two nuclear medicine physicians evaluated the lung scans for perfusion defects. Agreement between lung scan and angiographic findings was assessed with contingency tables. Sensitivity and specificity of lung scanning for accurate detection of PVS with angiographic findings as the reference standard were assessed by ROC analysis. Angiography depicted PVS in 90 of the total 136 pulmonary veins (66%). Lung scans correctly depicted 65 (72%) of the cases of PVS diagnosed with angiography. The sensitivity and specificity of lung scans were 76.0% and 88.9% for the right upper pulmonary vein, 70.6% and 94.1% for the right lower pulmonary vein, 77.3% and 58.3% for the left upper pulmonary vein, and 65.4% and 87.5% for the left lower pulmonary vein. Lung scan findings correlate with angiographic findings in the detection of primary PVS in pediatric patients. Perfusion lung scanning may have a role in angiographically diagnosed PVS by noninvasively showing relative perfusion at the tissue level.

  8. Computerized tomography versus perfusion lung scanning in canine radiation lung injury

    SciTech Connect

    Ahmed, I.H.; Logus, J.W.; El-Khatib, E.; Battista, J.J.; Ferri, H.; Lentle, B.C.; Man, G.C.; Man, S.F. )

    1990-03-01

    Computerized tomographic (CT) measurements of lung density were obtained before and serially after thoracic irradiation in dogs to detect the alterations caused by radiation therapy. Fourteen mongrel dogs were given either 2000 cGy (Group A, 10 dogs, right lower zone irradiation), 1000 cGy (Group B, 2 dogs, right lower zone irradiation), or 500 cGy (Group C, 2 dogs, right lung irradiation) in one fraction. Once before and bi-weekly after irradiation, the anesthetized dogs had thoracic CT scans. CT numbers for the irradiated area were compared to their preirradiation control values. Macro-aggregated albumin (MAA) perfusion lung scans were also obtained before and at weekly intervals after irradiation and were evaluated visually and quantitatively for abnormalities. When both these tests were abnormal, or at the end of the scheduled study, the dogs were sacrificed to confirm radiation lung injury histologically. Our results showed that CT numbers (as a measure of tissue density) were higher with higher doses of radiation. Among all the techniques used, only the quantitative assessment of macro-aggregated albumin perfusion scan detected abnormalities in all the dogs given 2000 cGy. Their abnormalities correlated well with the presence of radiation lung damage histologically, however, the applicability of these methods in the detection of early injury has to be further evaluated.

  9. Ventilation/perfusion lung scan in pulmonary veno-occlusive disease.

    PubMed

    Seferian, Andrei; Helal, Badia; Jaïs, Xavier; Girerd, Barbara; Price, Laura C; Günther, Sven; Savale, Laurent; Dorfmüller, Peter; Parent, Florence; Sitbon, Olivier; Humbert, Marc; Simonneau, Gérald; Montani, David

    2012-07-01

    Pulmonary veno-occlusive disease (PVOD), a rare form of pulmonary arterial hypertension (PAH), requires histological proof for definitive diagnosis; however, lung biopsy is not recommended in PAH. Recent conjoint European Respiratory Society/European Society of Cardiology guidelines suggest that nonmatched perfusion defects on ventilation/perfusion (V'/Q') lung scanning in PAH patients may suggest PVOD. The aim of our study was to evaluate V'/Q' lung scans in a large cohort of PVOD and idiopathic or heritable PAH patients. V'/Q' lung scans from 70 patients with idiopathic or heritable PAH and 56 patients with confirmed or highly probable PVOD were reviewed in a double-blind manner. The vast majority of V'/Q' lung scans were normal or without significant abnormalities in both groups. No differences in ventilation or perfusion lung scans were observed between PAH and PVOD patients (all p>0.05). Furthermore, no differences were observed between confirmed (n=31) or highly probable PVOD (n=25). Nonmatched perfusion defects were found in seven (10%) idiopathic PAH patients and four (7.1%) PVOD patients (p>0.05). Nonmatched perfusion defects were rarely seen in a large cohort of idiopathic or heritable PAH and PVOD patients. Future recommendations should be amended according to these results suggesting that V'/Q' lung scanning is not useful in discriminating PVOD from idiopathic PAH.

  10. Lung scan perfusion defects limited to matching pleural effusions: low probability of pulmonary embolism

    SciTech Connect

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

    1985-12-01

    Patients with a new pleural effusion are often sent for a ventilation-perfusion scan to exclude a pulmonary embolism. This retrospective study assessed the probability of pulmonary embolism when a pleural effusion and a perfusion defect of similar size are the only significant imaging abnormalities. In 451 reports of patients who were scanned for suspected pulmonary embolism, 53 had perfusion defects secondary to pleural effusion without other significant perfusion defects. Using pulmonary angiography, venography, analysis of pleural fluid, clinical course, and other radiographic and laboratory studies to establish the final diagnosis, only two patients had documented venous thrombotic disease: one had pulmonary emboli, the other thrombophlebitis. Lung scans having significant perfusion defects limited to pleural effusions and matching them in size have a low probability for pulmonary embolism.

  11. Correlation between the clinical pretest probability score and the lung ventilation and perfusion scan probability

    PubMed Central

    Bhoobalan, Shanmugasundaram; Chakravartty, Riddhika; Dolbear, Gill; Al-Janabi, Mazin

    2013-01-01

    Purpose: Aim of the study was to determine the accuracy of the clinical pretest probability (PTP) score and its association with lung ventilation and perfusion (VQ) scan. Materials and Methods: A retrospective analysis of 510 patients who had a lung VQ scan between 2008 and 2010 were included in the study. Out of 510 studies, the number of normal, low, and high probability VQ scans were 155 (30%), 289 (57%), and 55 (11%), respectively. Results: A total of 103 patients underwent computed tomography pulmonary angiography (CTPA) scan in which 21 (20%) had a positive scan, 81 (79%) had a negative scan and one (1%) had an equivocal result. The rate of PE in the normal, low-probability, and high-probability scan categories were: 2 (9.5%), 10 (47.5%), and 9 (43%) respectively. A very low correlation (Pearson correlation coefficient r = 0.20) between the clinical PTP score and lung VQ scan. The area under the curve (AUC) of the clinical PTP score was 52% when compared with the CTPA results. However, the accuracy of lung VQ scan was better (AUC = 74%) when compared with CTPA scan. Conclusion: The clinical PTP score is unreliable on its own; however, it may still aid in the interpretation of lung VQ scan. The accuracy of the lung VQ scan was better in the assessment of underlying pulmonary embolism (PE). PMID:24379532

  12. Automated lung outline reconstruction in ventilation-perfusion scans using principal component analysis techniques.

    PubMed

    Serpen, G; Iyer, R; Elsamaloty, H M; Parsai, E I

    2003-03-01

    The present work addresses the development of an automated software-based system utilized in order to create an outline reconstruction of lung images from ventilation-perfusion scans for the purpose of diagnosing pulmonary embolism. The proposed diagnostic software procedure would require a standard set of digitized ventilation-perfusion scans in addition to correlated chest X-rays as key components in the identification of an ideal template match used to approximate and reconstruct the outline of the lungs. These reconstructed lung images would then be used to extract the necessary PIOPED-compliant features which would warrant a pulmonary embolism diagnosis. In order to evaluate this issue, two separate principal component analysis (PCA) algorithms were employed independently, including Eigenlungs, which was adapted from the Eigenfaces method, and an artificial neural network. The results obtained through MATLAB(TM) simulation indicated that lung outline reconstruction through the PCA approach carries significant viability.

  13. Ventilation/perfusion lung scan probability category distributions in university and community hospitals.

    PubMed

    Lowe, V J; Bullard, A G; Coleman, R E

    1995-12-01

    The criteria used in the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study for the interpretation of ventilation/perfusion scans are widely used and the probability of pulmonary embolism is determined from these criteria. The prevalence of pulmonary embolism in the PIOPED study was 33%. To investigate the similarity of patient populations who have ventilation/perfusion scans at one of the medical centers that participated in the PIOPED study and a small community hospital, the authors evaluated the probability category distributions of lung scans at the two institutions. They retrospectively interpreted 54 and 49 ventilation/perfusion lung scans selected from January, 1991, to June, 1992, at Duke University Medical Center and at Central Carolina Hospital, respectively. Studies were interpreted according to the PIOPED criteria. The percentage of studies assigned to each category at Duke University Medical Center and Central Carolina Hospital were 17% and 27% normal or very low probability, 31% and 59% low probability, 39% and 10% intermediate probability, and 13% and 4% high probability, respectively. The different distribution of probability categories between university and community hospitals suggests that the prevalence of disease may also be different. The post-test probability of pulmonary embolism is related to the prevalence of disease and the sensitivity and specificity of the ventilation/perfusion scan. Because these variables may differ in community hospital settings, the post-test probability of pulmonary embolism as determined by data from the PIOPED study should only be used in institutions with similar populations. Clinical management based upon the results of the PIOPED study may not be applicable to patients who have ventilation/perfusion scans performed in a community hospital.

  14. 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.

  15. Pulmonary embolism among patients with a nearly normal ventilation/perfusion lung scan.

    PubMed

    Henry, J W; Stein, P D; Gottschalk, A; Raskob, G E

    1996-08-01

    Among patients with nearly normal ventilation/perfusion (V/Q) lung scans in the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED), pulmonary embolism (PE) was diagnosed more frequently in those who underwent pulmonary angiography than in those in whom PE was diagnosed on the basis of an adverse outcome while receiving no anticoagulant therapy. This may suggest that an adverse outcome is not apparent in patients with PE of such mild severity that the V/Q scan is nearly normal. If this were the case, patients with mild PE might not require treatment. The purpose of this investigation was to evaluate patients in PIOPED with nearly normal-V/Q lung scans. The V/Q scans and clinical characteristics of those in whom PE was diagnosed or excluded by pulmonary angiography (angiography group) were compared with those in whom PE was diagnosed or excluded by the presence or absence of an adverse outcome while not receiving anticoagulant therapy (outcome group). If the characteristics were the same, it would suggest that some patients with mild PE do well without treatment. If the characteristics were different, it would indicate that there is no evidence from these data that mild PE need not be treated. Data from PIOPED were evaluated from patients with suspected acute PE who had V/Q scans interpreted as nearly normal. There were 75 patients in the angiography group and 90 patients in the outcome group. Patients with entirely normal V/Q scans were excluded. PE was more frequent in the angiography group than in the outcome group, 8 of 75 (11%) vs 0 of 90 (0%) (p < 0.01). In patients with nearly normal V/Q scans who were in the outcome group in comparison to the angiography group, the V/Q scan showed fewer mismatched segmental perfusion defects, a lower percentage of low-probability V/Q interpretations by one of the two V/Q readers (compared with very low or normal probability), and a generally lower clinical assessment. The observed lower frequency of PE in the

  16. Distribution of ventilation/perfusion ratios in pulmonary embolism: an adjunct to the interpretation of ventilation/perfusion lung scans.

    PubMed

    Itti, Emmanuel; Nguyen, Séverine; Robin, Fabrice; Desarnaud, Serge; Rosso, Jean; Harf, Alain; Meignan, Michel

    2002-12-01

    Diagnosis of pulmonary embolism (PE) by visual interpretation of ventilation/perfusion (V/Q) scans is limited by the high percentages of patients classified in the intermediate- and low-probability categories. This study proposes a quantitative analysis of the distribution of V/Q ratios to better identify patients with PE. We studied 99 consecutive patients who underwent dual-isotope (81m)Kr/(99m)Tc-macroaggregate V/Q scanning and arterial blood gas analysis within 48 h. The 8-view V/Q scans were visually analyzed by 2 observers according to the revised criteria of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) (normal scan or low, intermediate, or high probability of PE). Quantitative analysis of the posterior-view distribution histogram of V/Q ratios was performed using dedicated software. Briefly, regions of interest were drawn around the lungs on the matched V/Q images, smooth filtering was applied, normalized regional V/Q ratios were calculated within each pixel, and a distribution histogram was built. Patients with normal scans (n = 16) had a predominance of V/Q ratios (63.3% +/- 13.0%) between 0.8 and 1.2. They had only 9.8% +/- 5.8% of ratios > 1.2, and the remaining 26.9% +/- 7.5% of ratios were <0.8. By contrast, patients with PE (n = 34) were characterized by a significant increase (15.5 +/- 10.0%, P = 0.04) in high V/Q ratios (>1.2) and a significant increase (34.5% +/- 8.2%, P = 0.003) in low V/Q ratios (<0.8). Interestingly, a similar pattern was found in patients with a high PIOPED probability of PE, 21.3% +/- 11.0% and 37.5% +/- 9.2%, respectively. Within the nondiagnostic group (intermediate- + low-probability scans, n = 58), 17 patients were finally diagnosed with PE. Analysis of the distribution histogram in this group allowed the identification of 5 patients with PE (specificity, 78%). A quantitative approach to lung scan interpretation, based on the distribution histogram of V/Q ratios, may be helpful for categorizing

  17. 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.

  18. Automatic extraction of PIOPED interpretations from ventilation/perfusion lung scan reports.

    PubMed

    Fiszman, M; Haug, P J; Frederick, P R

    1998-01-01

    Free-text documents are the main type of data produced by a radiology department in a hospital information system. While this type of data is readily accessible for clinical data review it can not be accessed by other applications to perform medical decision support, quality assurance, and outcome studies. In an attempt to solve this problem, natural language processing systems have been developed and tested against chest x-rays reports to extract relevant clinical information and make it accessible to other computer applications. We have used a natural language processing tool called SymText to extract relevant clinical information from a different type of radiology report, the Ventilation/Perfusion lung scan report. Results of this effort can be analyzed in terms of precision and recall. The overall precision was 0.88 and recall was 0.92. In addition, the natural language processing system functions differently in reports with and without an impression section. If this type of information can be successfully extracted from radiology reports, one can develop quality monitors for the diagnostic performance of the radiologist by correlating the impressions with gold standard data present in a hospital information system. Avoiding the manual effort previously necessary to create quality assurance data, can lead to a higher frequency of quality review in a radiology department.

  19. Automatic extraction of PIOPED interpretations from ventilation/perfusion lung scan reports.

    PubMed Central

    Fiszman, M.; Haug, P. J.; Frederick, P. R.

    1998-01-01

    Free-text documents are the main type of data produced by a radiology department in a hospital information system. While this type of data is readily accessible for clinical data review it can not be accessed by other applications to perform medical decision support, quality assurance, and outcome studies. In an attempt to solve this problem, natural language processing systems have been developed and tested against chest x-rays reports to extract relevant clinical information and make it accessible to other computer applications. We have used a natural language processing tool called SymText to extract relevant clinical information from a different type of radiology report, the Ventilation/Perfusion lung scan report. Results of this effort can be analyzed in terms of precision and recall. The overall precision was 0.88 and recall was 0.92. In addition, the natural language processing system functions differently in reports with and without an impression section. If this type of information can be successfully extracted from radiology reports, one can develop quality monitors for the diagnostic performance of the radiologist by correlating the impressions with gold standard data present in a hospital information system. Avoiding the manual effort previously necessary to create quality assurance data, can lead to a higher frequency of quality review in a radiology department. PMID:9929341

  20. 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.

  1. Review of criteria appropriate for a very low probability of pulmonary embolism on ventilation-perfusion lung scans: a position paper.

    PubMed

    Stein, P D; Gottschalk, A

    2000-01-01

    The "low-probability" interpretation of ventilation-perfusion lung scans has been characterized as misleading or even dangerous because of the high prevalence of pulmonary embolism associated with such an interpretation. Since the completion of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study, analyses of the PIOPED database have allowed identification of several abnormalities seen on ventilation-perfusion scans that have a positive predictive value (PPV) for pulmonary embolism of less than 10%. These include nonsegmental perfusion abnormalities (PPV = 8%), perfusion defects smaller than the corresponding areas of increased opacity at chest radiography (PPV = 8%), matched ventilation-perfusion abnormalities in two or three zones of a single lung (PPV = 3%), one to three small segmental perfusion defects (PPV = 1%), triple matched defects in the upper or middle lung zone (PPV = 4%), and the stripe sign (PPV = 7%). Use of these abnormalities as interpretative criteria constitutes "very low probability" interpretation and will reduce the number of low-probability interpretations of ventilation-perfusion lung scans, which may be considered nondiagnostic because of the unacceptably high rate of false-negative results. This will enhance the utility of the ventilation-perfusion lung scan for screening patients with suspected pulmonary embolism.

  2. 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.

  3. Utility of ventilation and perfusion scan in the diagnosis of young military recruits with an incidental finding of hyperlucent lung.

    PubMed

    Arslan, N; Ilgan, S; Ozkan, M; Yuksekol, I; Bulakbasi, N; Pabuscu, Y; Ozguven; Bayhan, H

    2001-05-01

    Swyer-James-MacLeod syndrome (SJMS) is considered to be a relatively uncommon disease presenting with unilateral hyperlucent lung due to hypoplasia of a pulmonary artery and bronchiectasis of the affected lung. In this report, we describe the ventilation-perfusion (V/Q) scan findings of nine male recruits (aged 20-29 years, mean 24.4+/-2.96 years) with SJMS in whom the diagnosis was first established in adulthood. V/Q scan findings of all patients were compared with those on planar radiographs, pulmonary function studies, high resolution computed tomography (HRCT) and digital subtraction angiography (DSA). The ventilation (133Xe) and perfusion (99Tcm-macro-aggregated albumin) scans showed the characteristic pattern of a matched V/Q defect and marked air trapping on the washout phase on 133Xe scintigraphy. HRCT displayed hypodense lung with integrity of main airways, and markedly diminished vasculature on the affected side in all patients. A smaller pulmonary artery on the affected side with poor peripheral vasculature was observed with DSA in all patients. All patients had features of obstructive airway disease in varying degrees on pulmonary function studies. In contrast to other imaging methods, bronchiectasis as an etiological factor was displayed on HRCT. Some pulmonary areas, which were normal on HRCT and planar radiographs, showed air trapping on V/Q scan. Although a V/Q scan was more helpful in determining the extent of the disease and correlates well with conventional imaging methods, HRCT was the most valuable imaging method for the evaluation of aetiology in unilateral hyperlucent lung.

  4. Reversal of diffuse patchy pattern in lung perfusion scan in a case of severe pulmonary arterial hypertension.

    PubMed

    Kodama, Yoshihiko; Abe, Kohtaro; Hosokawa, Kazuya; Ohtani, Kisho; Nagao, Michinobu; Hirooka, Yoshitaka; Sunagawa, Kenji

    2015-01-01

    A diffuse patchy pattern in the perfusion scan of the lung is a hallmark of severe pulmonary arterial hypertension (PAH). However, the mechanisms of this unique pattern remain uncertain. We here present the case of a 19-year-old woman with severe PAH who demonstrated reversal of the diffuse patchy pattern with improvement of pulmonary blood flow within a month after upfront triple combination therapy. Our case is a first report showing reversibility of diffuse patchy pattern by a short-term treatment in severe PAH. These findings suggest the possibility that the mechanisms underlying the diffuse patchy pattern may involve reversible vasoconstriction in addition to remodeling of small pulmonary arteries.

  5. Ga-68 MAA Perfusion 4D-PET/CT Scanning Allows for Functional Lung Avoidance Using Conformal Radiation Therapy Planning.

    PubMed

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

    2016-02-01

    Ga-68-macroaggregated albumin ((68)Ga-perfusion) positron emission tomography/computed tomography (PET/CT) is a novel imaging technique for the assessment of functional lung volumes. The purpose of this study was to use this imaging technique for functional adaptation of definitive radiotherapy plans in patients with non-small cell lung cancer (NSCLC). This was a prospective clinical trial of patients with NSCLC who received definitive 3-dimensional (3D) conformal radiotherapy to 60 Gy in 30 fx and underwent pretreatment respiratory-gated (4-dimensional [4D]) perfusion PET/CT. The "perfused" lung volume was defined as all lung parenchyma taking up radiotracer, and the "well-perfused" lung volume was contoured using a visually adapted threshold of 30% maximum standardized uptake value (SUV max). Alternate 3D conformal plans were subsequently created and optimized to avoid perfused and well-perfused lung volumes. Functional dose volumetrics were compared using mean lung dose (MLD), V5 (volume receiving 5 Gy or more), V10, V20, V30, V40, V50, and V60 parameters. Fourteen consecutive patients had alternate radiotherapy plans created based on functional lung volumes. When considering the original treatment plan, the dose to perfused and well-perfused functional lung volumes was similar to that of the conventional anatomical lung volumes with an average MLD of 12.15, 12.67, and 12.11 Gy, respectively. Plans optimized for well-perfused lung improved functional V30, V40, V50, and V60 metrics (all P values <.05). The functional MLD of well-perfused lung was improved by a median of 0.86 Gy, P < .01. However, plans optimized for perfused lung only showed significant improvement in the functional V60 dose parameter (median 1.00%, P = .04) but at a detriment of a worse functional V5 (median 3.33%, P = .05). This study demonstrates proof of principle that 4D-perfusion PET/CT may enable functional lung avoidance during treatment planning of patients with NSCLC. Radiotherapy plans

  6. 3D ECG- and respiratory-gated non-contrast-enhanced (CE) perfusion MRI for postoperative lung function prediction in non-small-cell lung cancer patients: A comparison with thin-section quantitative computed tomography, dynamic CE-perfusion MRI, and perfusion scan.

    PubMed

    Ohno, Yoshiharu; Seki, Shinichiro; Koyama, Hisanobu; Yoshikawa, Takeshi; Matsumoto, Sumiaki; Takenaka, Daisuke; Kassai, Yoshimori; Yui, Masao; Sugimura, Kazuro

    2015-08-01

    To compare predictive capabilities of non-contrast-enhanced (CE)- and dynamic CE-perfusion MRIs, thin-section multidetector computed tomography (CT) (MDCT), and perfusion scan for postoperative lung function in non-small cell lung cancer (NSCLC) patients. Sixty consecutive pathologically diagnosed NSCLC patients were included and prospectively underwent thin-section MDCT, non-CE-, and dynamic CE-perfusion MRIs and perfusion scan, and had their pre- and postoperative forced expiratory volume in one second (FEV1 ) measured. Postoperative percent FEV1 (po%FEV1 ) was then predicted from the fractional lung volume determined on semiquantitatively assessed non-CE- and dynamic CE-perfusion MRIs, from the functional lung volumes determined on quantitative CT, from the number of segments observed on qualitative CT, and from uptakes detected on perfusion scans within total and resected lungs. Predicted po%FEV1 s were then correlated with actual po%FEV1 s, which were %FEV1 s measured postoperatively. The limits of agreement were also determined. All predicted po%FEV1 s showed significant correlation (0.73 ≤ r ≤ 0.93, P < 0.0001) and limits of agreement with actual po%FEV1 (non-CE-perfusion MRI: 0.3 ± 10.0%, dynamic CE-perfusion MRI: 1.0 ± 10.8%, perfusion scan: 2.2 ± 14.1%, quantitative CT: 1.2 ± 9.0%, qualitative CT: 1.5 ± 10.2%). Non-CE-perfusion MRI may be able to predict postoperative lung function more accurately than qualitatively assessed MDCT and perfusion scan. © 2014 Wiley Periodicals, Inc.

  7. 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

  8. Pulmonary ventilation/perfusion scan

    MedlinePlus

    ... JavaScript. A pulmonary ventilation/perfusion scan involves two nuclear scan tests to measure breathing (ventilation) and circulation ( ... In: Mettler FA, Guiberteau MJ, eds. Essentials of Nuclear Medicine Imaging . 6th ed. Philadelphia, PA: Elsevier Saunders; ...

  9. Quantitative ventilation-perfusion lung scans in infants and children: utility of a submicronic radiolabeled aerosol to assess ventilation

    SciTech Connect

    O'Brodovich, H.M.; Coates, G.

    1984-09-01

    The quantitative assessment of regional pulmonary ventilation and perfusion provides useful information regarding lung function. Its use in infants and young children, however, has been minimal because of practical and technical limitations when the distribution of ventilation is assessed by radioactive gases. In 16 infants and children we used an inexpensive commercially available nebulizer to produce a submicronic aerosol labeled with 99mtechnetium-diethylenetriamine pentacetic acid to assess ventilation quantitatively, and intravenous injections of 99mtechnetium-labeled macroaggregates of albumin to assess pulmonary perfusion quantitatively. Studies were safely completed in both ambulatory and critically ill patients, including two premature infants who had endotracheal tubes in place for ventilatory support. No sedation or patient cooperation is required. This technique enables any department of nuclear medicine to measure regional pulmonary ventilation and perfusion in infants and children.

  10. [Outcome of patients with suspected pulmonary thromboembolism and low probability ventilation/perfusion lung scan who receive no long-term anticoagulation].

    PubMed

    Calvo Romero, J M; Arévalo Lorido, J C; Carretero Gómez, J

    2005-08-01

    To know in our area the security of no long-term anticoagulation in patients with suspected pulmonary thromboembolism (PTE) and a low probability ventilation/perfusion (V/Q) lung scan. Retrospective review of a series of consecutive outpatients with suspected PTE and a low probability V/Q lung scan, according to the modified PIOPED criteria, who receive no long-term anticoagulation. Among 38 patients with a low probability V/Q lung scan, 31 (81.6%) did not receive long-term anticoagulation. The median age was 69.1 years (range 26-88 years), and 19 (61.3%) were female. The clinical probability of PTE was moderate in 27 patients (87.1%). Twenty-two patients (71%) had a venous lower extremities echography-doppler negative for deep vein thrombosis (DVT). The median follow-up was 6.3 months (range 3-12 months). There was one case (3.2%; 95% confidence interval, 0.1-16.7%) with demonstrated PTE and DVT, and there was no death. No long-term anticoagulation in outpatients with a moderate clinical probability of PTE, a low probability V/Q lung scan and a venous lower extremities echography-doppler negative for DVT may be secure in our area.

  11. Prevalence of acute pulmonary embolism in central and subsegmental pulmonary arteries and relation to probability interpretation of ventilation/perfusion lung scans.

    PubMed

    Stein, P D; Henry, J W

    1997-05-01

    The purpose of this investigation is to determine the prevalence of acute pulmonary embolism (PE) limited to subsegmental pulmonary arteries. Contrast-enhanced helical (spiral) and electron-beam CT, in the hands of experienced radiologists who are skillful with this modality, are sensitive for the detection of acute PE in central pulmonary arteries, but have a low sensitivity for the detection of PE limited to subsegmental pulmonary arteries. The potential for CT to diagnose PE, therefore, is partially dependent on the prevalence of PE limited to subsegmental pulmonary arteries. Data are from the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED). The largest pulmonary arteries that showed PE, as interpreted by the PIOPED angiographic readers, were identified in 375 patients in PIOPED with angiographically diagnosed PE. Among all patients with PE, 6% (95% confidence interval [CI], 4 to 9%) had PE limited to subsegmental branches of the pulmonary artery. Patients with high-probability ventilation/ perfusion (V/Q) scans had PE limited to subsegmental branches in only 1% (95% CI, 0 to 4%). Among patients with low-probability V/Q lung scans, 17% (95% CI, 8 to 29%) had PE limited to the subsegmental branches. Patients with low-probability V/Q scans and no prior cardiopulmonary disease had PE limited to the subsegmental pulmonary arteries in 30% (95% CI, 13 to 53%), whereas patients with low-probability V/Q scans who had prior cardiopulmonary disease had PE limited to subsegmental pulmonary arteries in 8% (95% CI, 2 to 22%) (p < 0.05). Based on data from all patients with PE in PIOPED, the prevalence of PE limited to subsegmental pulmonary arteries is low, 6%. PE limited to subsegmental pulmonary arteries was most prevalent among patients with low-probability V/Q scans, particularly if they had no prior cardiopulmonary disease.

  12. Distributions of perfusion and lung water.

    PubMed

    Ekeh, S U; Chu, R Y; Ficken, V J; Allen, E W; Ryals, C J

    1990-01-01

    We investigated the feasibility of using 123I-iodoantipyrine (123I-IAP) and 99mTc-labeled macroaggregated albumin (99mTc-MAA) to describe and compare the distributions of perfusion and water content in lung injuries. These radiopharmaceuticals were administered to 9 rabbits, 5 control and 4 with lung injuries. Isolated lungs were imaged by a scintillation gamma camera. The distribution of 123I-IAP outlined the entire lung mass whereas perfusion defect in the distribution of 99mTc-MAA was seen clearly in the case of severe lung injury.

  13. Can pulmonary angiography be limited to the most suspicious side if the contralateral side appears normal on the ventilation/perfusion lung scan? Data from PIOPED. Prospective Investigation of Pulmonary Embolism Diagnosis.

    PubMed

    Gottschalk, A; Stein, P D; Henry, J W; Relyea, B

    1996-08-01

    The purpose of this investigation was to determine the frequency of pulmonary embolism (PE) in a single lung that showed a normal ventilation/perfusion (V/Q) lung scan when the V/Q scan on the contralateral side was interpreted as non-high-probability for PE. Data are from the national collaborative study Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED). PE was diagnosed or excluded in all lungs by pulmonary angiography. Single lungs with no V/Q abnormalities, when the V/Q scan on the contralateral side was interpreted as non-high-probability for PE, showed PE in 2 of 19 (11%) (95% confidence interval [CI], 1 to 33%). If PE was excluded by angiography on the side of the abnormal V/Q scan, then PE on the side of the normal V/Q scan was shown in only 1 of 19 (5%) (95% CI, 0 to 26%). A normal V/Q scan in a single lung, when the contralateral lung was interpreted as non-high-probability for PE, did not completely exclude PE on the apparently normal side. In such lungs, the probability of PE was in the range of low-probability interpretations. If the pulmonary angiogram showed no PE on the side of the abnormal V/Q scan, the probability of PE on the side of the normal V/Q scan satisfied the definition of very low probability for PE. This observation in patients undergoing pulmonary angiography may assist in determining whether the pulmonary angiogram should be bilateral.

  14. [Evaluation of lung perfusion scintigraphy without ventilation scintigraphy in the diagnosis of pulmonary thromboembolism].

    PubMed

    Jurkiene, Nemira

    2002-01-01

    The role of perfusion lung scintigraphy in the diagnosis of pulmonary embolism (PE) is reviewed. During the study 227 perfusion lung scans were obtained. The scans were grouped according to the PIOPED criteria into 5 groups: normal scans, very low, low, intermediate and high PE probability. The perfusion scans were analyzed according to the original PIOPED criteria, without ventilation scans. Evidence is provided that a normal perfusion scan excludes pulmonary embolism, and that a high probability lung scan, defined as a segmental perfusion defect with locally normal chest X-ray or findings in X-ray are smaller, sufficiently confirms the presence of pulmonary embolism in the majority of these patients (92.2%).

  15. 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.

  16. Lung perfusion studies after transcatheter closure of persistent ductus arteriosus with the Amplatzer duct occluder.

    PubMed

    Polat, Tugcin Bora; Celebi, Ahmet; Hacımahmutoglu, Sevim; Akdeniz, Celal; Erdem, Abdullah; Fırat, Fatih

    2010-09-01

    Reduced left lung perfusion has been described after transcatheter closure of the patent ductus arteriosus (PDA) with several prostheses. Although the Amplatzer ductal occluder (ADO) device is currently the most widely used occluder for closure of large-sized PDAs, the potential consequences of flow distribution to the lungs of this device have not been completely clarified. We evaluated lung perfusion following occlusion of PDA with the ADO device. Forty-seven patients underwent successful transcatheter PDA occlusion using the ADO device were included in this study. Lung perfusion scans were performed 6 months after the procedure. Decreased perfusion to the left lung (defined as < 40% of total lung flow) was observed in 17 patients (36%), 5 of whom were low-weight symptomatic infants. Ductal ampulla length was significantly shorter and minimal ductal diameter to ampulla diameter ratio was significantly higher in patients with decreased left lung perfusion and correlated well with left lung perfusion values (r = 0.516 and r = -0.501, respectively). A cut-off value of ≤ 5.8 mm for the ductal ampulla length and ≥ 1.9 for ampulla diameter to ampulla length ratio showed high sensitivity and specificity for reduced lung perfusion. The incidence of abnormal left lung perfusion is high 6 months after transcatheter closure of PDA with the ADO, more likely in the low weight symptomatic infants and in patients with a short duct or a relatively shallow duct having abrupt narrowing of a large ampulla.

  17. Lung gallium scan

    MedlinePlus

    ... the lungs. This is most often due to sarcoidosis or a certain type of pneumonia. Normal Results ... it may mean any of the following problems: Sarcoidosis (disease in which inflammation occurs in the lungs ...

  18. Dual-energy lung perfusion and ventilation CT in children.

    PubMed

    Goo, Hyun Woo

    2013-03-01

    Dual-energy thoracic CT provides two key insights into lung physiology, i.e. regional perfusion and ventilation, and has been actively investigated to find clinically relevant applications since the introduction of dual-source CT. This functional information provided by dual-energy thoracic CT is supplementary because high-resolution thoracic anatomy is entirely preserved on dual-energy thoracic CT. In addition, virtual non-contrast imaging can omit pre-contrast scanning. In this respect, dual-energy CT imaging technique is at least dose-neutral, which is a critical requirement for paediatric imaging. In this review, imaging protocols, analysis methods, clinical applications and diagnostic pitfalls of dual-energy thoracic CT for evaluating lung perfusion and ventilation in children are described.

  19. TU-G-BRA-01: Assessing Radiation-Induced Reductions in Regional Lung Perfusion Following Stereotactic Radiotherapy for Lung Cancer

    SciTech Connect

    McGurk, R; Green, R; Lawrence, M; Schreiber, E; Das, S; Zagar, T; Marks, L; Sheikh, A; McCartney, W; Rivera, P

    2015-06-15

    Purpose: The dose-dependent nature of radiation therapy (RT)-induced lung injury following hypo-fractionated stereotactic RT is unclear. We herein report preliminary results of a prospective study assessing the magnitude of RT-induced reductions in regional lung perfusion following hypo-fractionated stereotactic RT. Methods: Four patients undergoing hypo-fractionated stereotactic lung RT (SBRT: 12 Gy x 4 fractions or 10 Gy x 5 fractions) had a pre-treatment SPECT (single-photon emission computed tomography) perfusion scan providing a 3D map of regional lung perfusion. Scans were repeated 3–6 months post-treatment. Pre- and post SPECT scans were registered to the planning CT scan (and hence the 3D dose data). Changes in regional perfusion (counts per cc on the pre-post scans) were computed in regions of the lung exposed to different doses of radiation (in 5 Gy intervals), thus defining a dose-response function. SPECT scans were internally normalized to the regions receiving <5 Gy. Results: At 3 months post-RT, the changes in perfusion are highly variable. At 6 months, there is a consistent dose-dependent reduction in regional perfusion. The average percent decline in regional perfusion was 10% at 15–20 Gy, 20% at 20–25 Gy, and 30% at 25–30 Gy representing a relatively linear dose response with an approximate 2% reduction per Gray for doses in excess of 10 Gy. There was a subtle increase in perfusion in the lung receiving <10 Gy. Conclusion: Hypo-fractionated stereotactic RT appears to cause a dose-dependent reduction in regional lung perfusion. There appears to be a threshold effect with no apparent perfusion loss at doses <10 Gy, though this might be in part due to the normalization technique used. Additional data is needed from a larger number of patients to better assess this issue. This sort of data can be used to assist optimizing RT treatment plans that minimize the risk of lung injury. Partly supported by the NIH (CA69579) and the Lance Armstrong

  20. 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

  1. 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.

  2. Radiation injury in rat lung: I. Prostacyclin (PGI/sub 2/) production, arterial perfusion, and ultrastructure

    SciTech Connect

    Ts'ao, C.; Ward, W.F.; Port, C.D.

    1983-11-01

    Pulmonary prostacyclin (PGI/sub 2/) production, arterial perfusion, and ultrastructure were correlated in rats sacrificed from 1 day to 6 months after a single exposure of 25 Gy of gamma rays to the right hemithorax. PGI/sub 2/ production by the irradiated lung decreased to approximately half the normal value 1 day after irradiation (P < 0.05), then increased steadily throughout the study. By 6 months postirradiation, the right lung produced two to three times as much PGI/sub 2/ as did either shielded left lung or sham-irradiated lungs (P < 0.05). Perfusion scans revealed hyperemia of the right lung from 1 to 14 days after irradiation. From its peak at 14 days postirradiation, however, perfusion of the irradiated lung decreased steadily, then reached a plateau from 3 to 6 months at less than half that in the shielded left lung. Electron micrographs of the right lung revealed perivascular edema from 1 to 30 days after irradiation. The right lung then exhibited changes typical of radiation pneumonitis followed by progressive interstitial fibrosis. Platelet aggregates were not observed at any time. Thus, decreased PGI/sub 2/ production is an immediate but transient response of the lung to radiation injury. Then from 2 to 6 months after irradiation, the fibrotic, hypoperfused lung produces increasing amounts of the potent vasodilator and antithrombotic agent, PGI/sub 2/. Pulmonary PGI/sub 2/ production and arterial perfusion are inversely correlated for at least 6 months after hemithoracic irradiation.

  3. Automated quantitative analysis of ventilation-perfusion lung scintigrams

    SciTech Connect

    Burton, G.H.; Vernon, P.; Seed, W.A.

    1984-05-01

    An automated computer analysis of ventilation (Kr-81m) and perfusion (Tc-99m) lung images has been devised that produces a graphical image of the distribution of ventilation and perfusion, and of ventilation-perfusion ratios. The analysis has overcome the following problems: the identification of the midline between two lungs and the lung boundaries, the exclusion of extrapulmonary radioactivity, the superimposition of lung images of different sizes, and the format for presentation of the data. Therefore, lung images of different sizes and shapes may be compared with each other. The analysis has been used to develop normal ranges from 55 volunteers. Comparison of younger and older age groups of men and women show small but significant differences in the distribution of ventilation and perfusion, but no differences in ventilation-perfusion ratios.

  4. Reversible ventilation and perfusion abnormalities in unilateral obstructed lung

    SciTech Connect

    Ward, H.E.; Jones, R.L.; King, E.G.; Sproule, B.J.; Fortune, R.L.

    1982-01-01

    An intraluminal carcinoid tumor obstructing the left mainstem bronchus produced hypoxemia through alteration in ventilation/perfusion matching. Studies of regional lung function using 133-xenon (/sup 133/Xe) and a multiprobe computerized instrumentation system documented a reduction of perfusion to 22 percent and ventilation to 6 percent of the total. There was negligible washout of intravenously injected /sup 133/Xe from the left lung consistent with air trapping. Four days after left mainstem bronchial sleeve resection, perfusion, ventilation and washout of injected xenon had significantly improved and by four months postresection, all measurements were virtually normal, although complete restoration of perfusion in relation to ventilation was delayed. Regional lung function studied with a multiprobe system in this patient provided a clinical model for the study of ventilation and perfusion inter-relationships in large airway obstruction and demonstrated that a prolonged time may be required for return of perfusion to normal.

  5. Radioisotope scanning of the lungs

    PubMed Central

    Bell, T. K.; Ferguson, R.; McIlrath, E. I.; Weaver, J. A.

    1968-01-01

    Lung scanning with macroaggregated albumin 131I was carried out in 128 patients. The technique appears to be without hazard. It is particularly useful in the detection of pulmonary embolism, but the pattern is non-specific and changes occur in other cardio-respiratory diseases. On the basis of these observations pulmonary scanning is regarded as a useful adjunct in the study of pulmonary embolism, but it cannot serve as a specific diagnostic procedure since similar patterns of scan may be found in many conditions. Images PMID:4230042

  6. Ex Vivo Lung Perfusion: Establishment and Operationalization in Iran.

    PubMed

    Shafaghi, Shadi; Abbasi Dezfuli, Azizollah; Ansari Aval, Zahra; Sheikhy, Kambiz; Farzanegan, Behrooz; Mortaz, Esmaeil; Emami, Habib; Aigner, Clemens; Hosseini-Baharanchi, Fatemeh Sadat; Najafizadeh, Katayoun

    2017-02-01

    Although the number of lung transplants is limited because of general shortage of organ donors, ex vivo lung perfusion is a novel method with 2 main benefits, including better evaluation of lung potential and recovery of injured lungs. The main aim of this study was to establish and operationalize ex vivo lung perfusion as the first experience in Iran. This was a prospective operational research study on 5 cases, including 1 pig from Vienna Medical University and 4 patients from Masih Daneshvari Hospital. All organ donations from brain dead donors were evaluated according to lung transplant or ex vivo lung perfusion criteria from May 2013 to July 2015 in Tehran, Iran. If a donor did not have any sign of severe chest trauma or pneumonia but had poor oxygenation due to possible atelectasis or neurogenic pulmonary edema, their lungs were included for ex vivo lung perfusion. A successful trend in the difference between the pulmonary arterial Po2 and the left atrial Po2 was observed, as well as an increasing pattern in other functional parameters, including dynamic lung compliance and a decreasing trend in pulmonary vascular resistance. These initial trials indicate that ex vivo lung perfusion can lead to remarkable progress in lung transplant in Iran. They also provide several important pieces of guidance for successful ex vivo lung perfusion, including the necessity of following standard lung retrieval procedures and monitoring temperature and pressure precisely. The development of novel methods can provide opportunities for further research studies on lungs of deceased donors and lead to undiscovered findings. By keeping this science up to date in Iran and developing such new and creative methods, we can reveal effective strategies to promote the quality of donor lungs to support patients on transplant wait lists.

  7. 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

  8. Perfusion scintigraphy and patient selection for lung volume reduction surgery.

    PubMed

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

    2010-10-01

    It is unclear if lung perfusion can predict response to lung volume reduction surgery (LVRS). To study the role of perfusion scintigraphy in patient selection for LVRS. 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. 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. 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.

  9. Steal phenomenon-induced lung perfusion defects in pulmonary arteriovenous fistulas: assessment with automated perfusion SPECT-CT fusion images.

    PubMed

    Suga, Kazuyoshi; Iwanaga, Hideyuki; Tokuda, Osamu; Okada, Munemasa; Tanaka, Nobuyuki; Matsunaga, Naofumi

    2010-09-01

    Lung perfusion impairment in patients with pulmonary arteriovenous fistula (AVF) was evaluated by automated deep inspiratory breath-hold (DIBrH) perfusion single-photon emission computed tomography (SPECT)-CT fusion images. Participants were 14 patients with a single (N=6) or multiple nodular AVFs (N=8) diagnosed by contrast-enhanced CT scan and/or pulmonary angiography. After the injection of 185MBq Tc-99m-macroaggregated albumin, a whole-body scan was obtained to quantify an intrapulmonary right-to-left shunt. Subsequently, DIBrH SPECT was obtained using the continuous rotating acquisition mode of a dual-headed SPECT system, which was automatically coregistered with DIBrH CT. The anatomic relationship between AVF and perfusion defects was assessed on the fusion images. The whole-body scan depicted systemic organs indicating the presence of an intrapulmonary right-to-left shunt in all the patients. DIBrH SPECT showed 34 perfusion defects in these patients, which were located at the AVF and in the surrounding lungs of the AVF on the fusion images, regardless of the absence of morphologic abnormality on CT in all the patients. These defects were considered to be caused by the 'steal phenomenon' associated with the high and fast pulmonary arterial flow to each AVF, which were more extensive and severe in the multiple AVFs compared with a single AVF (P=0.0012), occasionally extending to the entire lobe with AVF or even to the adjacent lobe. In five patients, the fusion images detected a total of six tiny AVFs with unexpectedly extensive 'steal phenomenon'-induced defects, which had been missed by other radiological imaging techniques. The summed value of the shunt index estimated by the whole-body scan and the lung perfusion defect extent estimated by DIBrH SPECT was significantly correlated with PaO2 in all the patients (P < 0.0001), with a better correlation compared with the shunt index alone. In addition to the right-to-left shunt, 'steal phenomenon

  10. Lung mass appearing as a dilated left ventricle on Tc-99m tetrofosmin myocardial perfusion scintigraphy.

    PubMed

    Gnanasegaran, Gopinath; Williams, Robert; Mclean, Emma; O' Connell, Rachel; Nunan, Thomas O; O'Doherty, Michael J

    2009-09-01

    Tc-99m tetrofosmin is a common tracer used in myocardial perfusion scintigraphy. Several benign and malignant tumors also take up tetrofosmin. We present a case of a 60-year-old woman with a history of a left lung mass awaiting resection. The patient was referred for a myocardial perfusion scan for preoperative risk assessment. The myocardial perfusion scan revealed a large cavitated lesion mimicking a dilated left ventricle and the CT scan revealed a large mass in the left lung with central necrosis displacing the heart and mediastinum. The patient underwent thoracotomy with resection of the mass and the histology confirmed atypical carcinoid. This case highlights noncardiac uptake of Tc-99m tetrofosmin in an atypical carcinoid.

  11. Magnetic Resonance Imaging of Ventilation and Perfusion in the Lung

    NASA Technical Reports Server (NTRS)

    Prisk, Gordon Kim (Inventor); Hopkins, Susan Roberta (Inventor); Buxton, Richard Bruce (Inventor); Pereira De Sa, Rui Carlos (Inventor); Theilmann, Rebecca Jean (Inventor); Cronin, Matthew Vincent (Inventor)

    2017-01-01

    Methods, devices, and systems are disclosed for implementing a fully quantitative non-injectable contrast proton MRI technique to measure spatial ventilation-perfusion (VA/Q) matching and spatial distribution of ventilation and perfusion. In one aspect, a method using MRI to characterize ventilation and perfusion in a lung includes acquiring an MR image of the lung having MR data in a voxel and obtaining a breathing frequency parameter, determining a water density value, a specific ventilation value, and a perfusion value in at least one voxel of the MR image based on the MR data and using the water density value to determine an air content value, and determining a ventilation-perfusion ratio value that is the product of the specific ventilation value, the air content value, the inverse of the perfusion value, and the breathing frequency.

  12. Arterial input function placement effect on computed tomography lung perfusion maps.

    PubMed

    Jimenez-Juan, Laura; Mehrez, Hatem; Dey, Chris; Homampour, Shabnam; Oikonomou, Anastasia; Ursani, Fatima; Paul, Narinder

    2016-02-01

    A critical source of variability in dynamic perfusion computed tomography (DPCT) is the arterial input function (AIF). However, the impact of the AIF location in lung DPCT has not been investigated yet. The purpose of this study is to determine whether the location of the AIF within the central pulmonary arteries influences the accuracy of lung DPCT maps. A total of 54 lung DPCT scans were performed in three pigs using different rates and volumes of iodinated contrast media. Pulmonary blood flow (PBF) perfusion maps were generated using first-pass kinetics in three different AIF locations: the main pulmonary trunk (PT), the right main (RM) and the left main (LM) pulmonary arteries. A total of 162 time density curves (TDCs) and corresponding PBF perfusion maps were generated. Linear regression and Spearman's rank correlation coefficient were used to compare the TDCs. PBF perfusion maps were compared quantitatively by taking twenty six regions of interest throughout the lung parenchyma. Analysis of variance (ANOVA) was used to compare the mean PBF values among the three AIF locations. Two chest radiologists performed qualitative assessment of the perfusion maps using a 3-point scale to determine regions of perfusion mismatch. The linear regression of the TDCs from the RM and LM compared to the PT had a median (range) of 1.01 (0.98-1.03). The Spearman rank correlation between the TDCs was 0.88 (P<0.05). ANOVA analysis of the perfusion maps demonstrated no statistical difference (P>0.05). Qualitative comparison of the perfusion maps resulted in scores of 1 and 2, demonstrating either identical or comparable maps with no significant difference in perfusion defects between the different AIF locations. Accurate PBF perfusion maps can be generated with the AIF located either at the PT, RM or LM pulmonary arteries.

  13. Serial perfusion in native lungs in patients with idiopathic pulmonary fibrosis and other interstitial lung diseases after single lung transplantation.

    PubMed

    Sokai, Akihiko; Handa, Tomohiro; Chen, Fengshi; Tanizawa, Kiminobu; Aoyama, Akihiro; Kubo, Takeshi; Ikezoe, Kohei; Nakatsuka, Yoshinari; Oguma, Tsuyoshi; Hirai, Toyohiro; Nagai, Sonoko; Chin, Kazuo; Date, Hiroshi; Mishima, Michiaki

    2016-04-01

    Lung perfusions after single lung transplantation (SLT) have not been fully clarified in patients with interstitial lung disease (ILD). The present study aimed to investigate temporal changes in native lung perfusion and their associated clinical factors in patients with ILD who have undergone SLT. Eleven patients were enrolled. Perfusion scintigraphy was serially performed up to 12 months after SLT. Correlations between the post-operative perfusion ratio in the native lung and clinical parameters, including pre-operative perfusion ratio and computed tomography (CT) volumetric parameters, were evaluated. On average, the perfusion ratio of the native lung was maintained at approximately 30% until 12 months after SLT. However, the ratio declined more significantly in idiopathic pulmonary fibrosis (IPF) than in other ILDs (p = 0.014). The perfusion ratio before SLT was significantly correlated with that at three months after SLT (ρ = 0.64, p = 0.048). The temporal change of the perfusion ratio in the native lung did not correlate with those of the CT parameters. The pre-operative perfusion ratio may predict the post-operative perfusion ratio of the native lung shortly after SLT in ILD. Perfusion of the native lung may decline faster in IPF compared with other ILDs. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Assessment of lung tumor response by perfusion CT.

    PubMed

    Coche, E

    2013-01-01

    Perfusion CT permits evaluation of lung cancer angiogenesis and response to therapy by demonstrating alterations in lung tumor vascularity. It is advocated that perfusion CT performed shortly after initiating therapy may provide a better evaluation of physiological changes rather than the conventional size assessment obtained with RECIST. The radiation dose,the volume of contrast medium delivered to the patient and the reproducibility of blood flow parameters remain an issue for this type of investigation.

  15. Ventilation/perfusion lung scintigraphy. Multiple applications besides pulmonary embolism.

    PubMed

    Sinzinger, Helmut; Rodrigues, Margarida; Kummer, Friedrich

    2013-01-01

    Ventilation/perfusion scintigraphy is the diagnostic tool of choice for detection and monitoring of pulmonary embolism. However, the knowledge on its value for other or concurrent pathologies is poor. In this review scintigraphic characteristics of the main pathologies, interpretation and artefacts are described. Together with the understanding of pathophysiology of the lung, the potential gain of information derived from ventilation/perfusion scintigraphy is much higher than generally believed. In conclusion, ventilation/perfusion scintigraphy not only in PE but also in other lung diseases is underused, its value and clinical potential underestimated.

  16. [Lung perfusion studies after percutaneous closure of patent ductus arteriosus using the Amplatzer Duct Occluder in children].

    PubMed

    Parra-Bravo, José Rafael; Apolonio-Martínez, Adriana; Estrada-Loza, María de Jesús; Beirana-Palencia, Luisa Gracia; Ramírez-Portillo, César Iván

    2015-01-01

    The closure of patent ductus arteriosus with multiple devices has been associated with a reduction in lung perfusion. We evaluated the pulmonary perfusion after percutaneous closure of patent ductus arteriosus with the Amplatzer Duct Occluder device using perfusion lung scan. Thirty patients underwent successful percutaneous patent ductus arteriosus occlusions using the Amplatzer Duct Occluder device were included in this study. Lung perfusion scans were preformed 6 months after the procedure. Peak flow velocities and protrusion of the device were analyzed by Doppler echocardiography. A left lung perfusion<40% was considered abnormal. The device implantation was successful in all patients. Average perfusion of left lung was 44.7±4.9% (37.8-61.4). Five patients (16.6%) showed decreased perfusion of the left lung. Age, low weight, the length of the ductus arteriosus and the minimum and maximum diameter/length of the ductus arteriosus ratio were statistically significant in patients with abnormalities of lung perfusion. It was observed protrusion the device in 6 patients with a higher maximum flow rate in the left pulmonary artery. The left lung perfusion may be compromised after percutaneous closure of patent ductus arteriosus with the Amplatzer Duct Occluder. The increased flow velocity in the origin of the left pulmonary artery can be a poor indicator of reduction in pulmonary perfusion and can occur in the absence of protrusion of the device. Copyright © 2014 Instituto Nacional de Cardiología Ignacio Chávez. Published by Masson Doyma México S.A. All rights reserved.

  17. Transplantation of initially rejected donor lungs after ex vivo lung perfusion.

    PubMed

    Wallinder, Andreas; Ricksten, Sven-Erik; Hansson, Christoffer; Riise, Gerdt C; Silverborn, Martin; Liden, Hans; Olausson, Michael; Dellgren, Göran

    2012-11-01

    Ex vivo lung perfusion has the potential to increase the number of patients treated with lung transplantation. Our initial clinical experience with ex vivo lung perfusion is reviewed as well as early clinical outcome in patients transplanted with reconditioned lungs. Six pairs of donor lungs deemed unsuitable for transplantation underwent ex vivo lung perfusion with Steen solution mixed with red blood cells to a hematocrit of 10% to 15%. After reconditioning, lung function was evaluated and acceptable lungs were transplanted. Technical experience with ex vivo lung perfusion as well as clinical outcome for patients transplanted with ex vivo lung perfusion-treated lungs were evaluated. Donor lungs initially rejected either as a result of an inferior partial pressure of arterial oxygen/ fraction of inspired oxygen (n = 5; mean, 20.5 kPa; range, 9.1-29.9 kPa) or infiltrate on chest radiograph (n = 1) improved their oxygenation capacity to a mean partial pressure of arterial oxygen/fraction of inspired oxygen of 57 ± 10 kPa during the ex vivo lung perfusion (mean improvement, 33.6 kPa; range, 21-51 kPa; P < .01). During evaluation, hemodynamic (flow, vascular resistance, pressure) and respiratory (peak airway pressure, compliance) parameters were stable. Two single lungs were not used for lung transplantation because of subpleural hematoma or edema. Six recipients from the regular waiting list underwent single (n = 2) or double (n = 4) lung transplantation. One patient had primary graft dysfunction grade 2 at 72 hours. Median time to extubation was 7 hours. All patients survived 30 days and were discharged in good condition from the hospital. The use of ex vivo lung perfusion seems safe and indicates that some lungs otherwise refused for lung transplantation can be recovered and transplanted with acceptable short-term results. Copyright © 2012 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  18. Argon and xenon ventilation during prolonged ex vivo lung perfusion.

    PubMed

    Martens, An; Montoli, Matteo; Faggi, Giulio; Katz, Ira; Pype, Jan; Vanaudenaerde, Bart M; Van Raemdonck, Dirk E M; Neyrinck, Arne P

    2016-03-01

    Evidence supports the use of ex vivo lung perfusion (EVLP) as a platform for active reconditioning before transplantation to increase the potential donor pool and to reduce the incidence of primary graft dysfunction. A promising reconditioning strategy is the administration of inhaled noble gases based on their organoprotective effects. Our aim was to validate a porcine warm ischemic lung injury model and investigate postconditioning with argon (Ar) or xenon (Xe) during prolonged EVLP. Domestic pigs were divided in four groups (n = 5 per group). In the negative control group, lungs were flushed immediately. In the positive control (PC) and treatment (Ar, Xe) groups, lungs were flushed after a warm ischemic interval of 2-h in situ. All grafts were evaluated and treated during normothermic EVLP for 6 h. In the control groups, lungs were ventilated with 70% N2/30% O2 and in the treatment groups with 70% Ar/30% O2 or 70% Xe/30% O2, respectively. Outcome parameters were physiological variables (pulmonary vascular resistance, peak airway pressures, and PaO2/FiO2), histology, wet-to-dry weight ratio, bronchoalveolar lavage, and computed tomography scan. A significant difference between negative control and PC for pulmonary vascular resistance, peak airway pressures, PaO2/FiO2, wet-to-dry weight ratio, histology, and computed tomography-imaging was observed. No significant differences between the injury group (PC) and the treatment groups (Ar, Xe) were found. We validated a reproducible prolonged 6-h EVLP model with 2 h of warm ischemia and described the physiological changes over time. In this model, ventilation during EVLP with Ar or Xe administered postinjury did not improve graft function. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. 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. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

  20. 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.

  1. 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 Central

    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. PMID:27168866

  2. Comparison of lung preservation solutions in human lungs using an ex vivo lung perfusion experimental model.

    PubMed

    Medeiros, Israel L; Pêgo-Fernandes, Paulo M; Mariani, Alessandro W; Fernandes, Flávio G; Unterpertinger, Fernando V; Canzian, Mauro; Jatene, Fabio B

    2012-09-01

    Experimental studies on lung preservation have always been performed using animal models. We present ex vivo lung perfusion as a new model for the study of lung preservation. Using human lungs instead of animal models may bring the results of experimental studies closer to what could be expected in clinical practice. Brain-dead donors whose lungs had been declined by transplantation teams were used. The cases were randomized into two groups. In Group 1, Perfadex®was used for pulmonary preservation, and in Group 2, LPDnac, a solution manufactured in Brazil, was used. An ex vivo lung perfusion system was used, and the lungs were ventilated and perfused after 10 hours of cold ischemia. The extent of ischemic-reperfusion injury was measured using functional and histological parameters. After reperfusion, the mean oxygenation capacity was 405.3 mmHg in Group 1 and 406.0 mmHg in Group 2 (p = 0.98). The mean pulmonary vascular resistance values were 697.6 and 378.3 dyn·s·cm-5, respectively (p =0.035). The mean pulmonary compliance was 46.8 cm H20 in Group 1 and 49.3 ml/cm H20 in Group 2 (p =0.816). The mean wet/dry weight ratios were 2.06 and 2.02, respectively (p=0.87). The mean Lung Injury Scores for the biopsy performed after reperfusion were 4.37 and 4.37 in Groups 1 and 2, respectively (p = 1.0), and the apoptotic cell counts were 118.75/mm² and 137.50/mm², respectively (p=0.71). The locally produced preservation solution proved to be as good as Perfadex®. The clinical use of LPDnac may reduce costs in our centers. Therefore, it is important to develop new models to study lung preservation.

  3. [A complete ventilation-perfusion mismatch following one-sided lung transplantation and postoperative hemothorax].

    PubMed

    Jellinek, H; Klepetko, W; Hiesmayr, M

    1992-03-01

    Eight days after single-lung transplantation for pulmonary hypertension, a patient presented with a hemothorax on the side of the transplanted lung that required acute thoracotomy. Pulmonary artery pressure had decreased from 78/32/58 mmHg prior to the transplant to 42/18/27 mmHg on the 2nd postoperative day. Therefore, a predominance of perfusion to the transplanted lung was expected. During induction of anesthesia, in spite of ventilation with pure oxygen the patient developed a hypoxic cardiac arrest (paO2 26 mmHg, 40% saturation measured by pulse oximetry) requiring external chest compression. Auscultation and chest movements suggested that the transplanted lung was not ventilated. Because blood flow went mainly to the transplanted lung, ventilation of the native lung was almost totally dead-space ventilation. To enable ventilation of the compressed transplanted lung, the patient was intubated using a single-lumen bronchial blocker tube to block the mainstem bronchus of the native lung. The transplanted lung could then be ventilated. Saturation increased and epinephrine re-established a stable circulation; 2500 ml blood were removed from the pleura without further complications. On the 7th postoperative day the patient was discharged from the intensive care unit without neurological deficits. A perfusion scan 28 days post-transplant revealed 89% of the perfusion going to the transplanted lung. Atelectasis of this lung resulted in a large intrapulmonary right-to-left shunt. Hypoxic pulmonary vasoconstriction could not ameliorate the shunt because of the high pulmonary vascular resistance of the native lung.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. The effect of ex vivo lung perfusion on microbial load in human donor lungs.

    PubMed

    Andreasson, Anders; Karamanou, Danai M; Perry, John D; Perry, Audrey; Ӧzalp, Faruk; Butt, Tanveer; Morley, Katie E; Walden, Hannah R; Clark, Stephen C; Prabhu, Mahesh; Corris, Paul A; Gould, Kate; Fisher, Andrew J; Dark, John H

    2014-09-01

    Ex vivo lung perfusion (EVLP) has emerged as a technique to potentially recondition unusable donor lungs for transplantation. Beneficial effects of EVLP on physiologic function have been reported, but little is known about the effect of normothermic perfusion on the infectious burden of the donor lung. In this study, we investigated the effect of EVLP on the microbial load of human donor lungs. Lungs from 18 human donors considered unusable for transplantation underwent EVLP with a perfusate containing high-dose, empirical, broad-spectrum anti-microbial agents. Quantitative cultures of bacteria and fungi were performed on bronchoalveolar lavage fluid from the donor lung before and after 3 to 6 hours of perfusion. The identification of any organisms and changes in number of colony forming units before and after EVLP were assessed and anti-microbial susceptibilities identified. Thirteen out of 18 lungs had positive cultures, with bacterial loads significantly decreasing after EVLP. Yeast loads increased when no anti-fungal treatment was given, but were reduced when prophylactic anti-fungal treatment was added to the circuit. Six lungs were ultimately transplanted into patients, all of whom survived to hospital discharge. There was 1 death at 11 months. Our study shows that EVLP with high-dose, empirical anti-microbial agents in the perfusate is associated with an effective reduction in the microbial burden of the donor lung, a benefit that has not previously been demonstrated. Copyright © 2014 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  5. 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

  6. 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.

  7. 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.

  8. 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. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

  9. First steps in membrane oxygenation and prolonged extracorporeal perfusion in Duesseldorf using the Bramson membrane lung.

    PubMed

    Schulte, Hagen D

    2003-05-01

    After a shortened history of conventional closed and open heart surgery, including hypothermia by surface cooling and extracorporeal circulation, the first application of a new membrane oxygenator developed by ML Bramson with an integrated temperature exchange system and a heart-lung machine (HLM) was reported in 1972. The aim was to have an efficient oxygenating and gas exchange artificial lung that allowed prolonged perfusions in patients with cardiogenic shock or acute respiratory insufficiency. After in vitro closed recirculation studies comparing different bubble, vertical screen, and the new membrane oxygenators, the Bramson HLM was used in dog experiments before starting clinical cardiac surgery with routine interventions (closure of an atrial septal defect). The first clinically prolonged support for more than three hours after a double valve replacement in a NYHA class IV patient failed. A partial venoarterial prolonged perfusion for 42 hours and 43 minutes in a 10-year-old girl after surgical correction of a partial av canal defect and postoperative development of consistent lung edema caused by myocardial failure after an ischemic time of 43 minutes was the first successful long-term perfusion case in Europe. These first experiences with the Bramson membrane lung formed the basis, in our group, for further investigations of different perfusion routes and cannulations in animal experiments. Also, scanning electron microscopy studies could be performed with experimentally and clinically used membranes. The development of disposable membrane lung devices, for instance, Lande-Edwards, Kolobow Scimed, and General Electric Peirce membrane lungs, ameliorated and improved the use of these devices considerably. Also, BRAMSON had developed a disposable membrane lung device that had proved to be very effective in animal experiments by 1972, but, unfortunately, this device did not become commercially available.

  10. Ventilation and perfusion magnetic resonance imaging of the lung

    PubMed Central

    Bauman, Grzegorz; Eichinger, Monika

    2012-01-01

    Summary A close interaction between the respiratory pump, pulmonary parenchyma and blood circulation is essential for a normal lung function. Many pulmonary diseases present, especially in their initial phase, a variable regional impairment of ventilation and perfusion. In the last decades various techniques have been established to measure the lung function. Besides the global pulmonary function tests (PFTs) imaging techniques gained increasing importance to detect local variations in lung function, especially for ventilation and perfusion assessment. Imaging modalities allow for a deeper regional insight into pathophysiological processes and enable improved planning of invasive procedures. In contrast to computed tomography (CT) and the nuclear medicine techniques, magnetic resonance imaging (MRI), as a radiation free imaging modality gained increasing importance since the early 1990 for the assessment of pulmonary function. The major inherent problems of lung tissue, namely the low proton density and the pulmonary and cardiac motion, were overcome in the last years by a constant progress in MR technology. Some MR techniques are still under development, a process which is driven by scientific questions regarding the physiology and pathophysiology of pulmonary diseases, as well as by the need for fast and robust clinically applicable imaging techniques as safe therapy monitoring tools. MRI can be considered a promising ionizing-free alternative to techniques like CT or nuclear medicine techniques for the evaluation of lung function. The goal of this article is to provide an overview on selected MRI techniques for the assessment of pulmonary ventilation and perfusion. PMID:22802864

  11. Protective effect of plasmin in marginal donor lungs in an ex vivo lung perfusion model.

    PubMed

    Motoyama, Hideki; Chen, Fengshi; Ohsumi, Akihiro; Hijiya, Kyoko; Okita, Kenji; Nakajima, Daisuke; Sakamoto, Jin; Yamada, Tetsu; Sato, Masaaki; Aoyama, Akihiro; Bando, Toru; Date, Hiroshi

    2013-05-01

    Donor lung thrombi are considered an important etiology for primary graft dysfunction in lung transplantation. We hypothesized that thrombolysis before lung transplantation could alleviate ischemia-reperfusion injury. This study was designed to evaluate the effect of the fibrinolytic agent plasmin on lungs damaged by thrombi in an ex vivo lung perfusion (EVLP) system. Rats were divided into control, non-plasmin, and plasmin groups (n = 7 each). In the control and plasmin groups, cardiac arrest was induced by withdrawal of mechanical ventilation without heparinization. Ventilation was restarted 150 minutes after cardiac arrest. The lungs were flushed, and the heart and lungs were excised en bloc. The lungs were perfused in the EVLP system for 60 minutes, and plasmin or placebo was administered upon EVLP initiation. Fibrin/fibrinogen degradation products in the perfusate were significantly higher in the plasmin group than in the control and non-control groups (p < 0.001 for both). Plasmin administration significantly decreased pulmonary vascular resistance (plasmin vs non-plasmin, p = 0.011) and inhibited the exacerbation of dynamic compliance (plasmin vs non-plasmin, p = 0.003). Lung weight gain was less in the plasmin group than in the non-plasmin group (p = 0.04). Our results confirmed that plasmin administration in an EVLP model dissolved thrombi in the lungs, resulting in reconditioning of the lungs as assessed by various physiologic parameters. Copyright © 2013 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  12. Cytokine expression profile in human lungs undergoing normothermic ex-vivo lung perfusion.

    PubMed

    Sadaria, Miral R; Smith, Phillip D; Fullerton, David A; Justison, George A; Lee, Joon H; Puskas, Ferenc; Grover, Frederick L; Cleveland, Joseph C; Reece, T Brett; Weyant, Michael J

    2011-08-01

    A donor lung shortage prevents patients from receiving life-saving transplants. Ex-vivo lung perfusion (EVLP) is a viable means of expanding the donor pool by evaluating and potentially improving donor lung function. The metabolic and inflammatory effects of EVLP on human lung tissue are currently unknown. We sought to establish representative cytokine expression in human donor lungs meeting acceptable lung transplant criteria after prolonged normothermic EVLP. Seven single human lungs not meeting traditional transplantation criteria for various reasons underwent normothermic EVLP. Lungs were perfused with deoxygenated colloid, rewarmed, and ventilated per standard protocol. Lung function was evaluated every hour. Biopsies were taken at 1, 6, and 12 hours. Inflammatory cytokines were quantitatively measured using a human cytokine magnetic bead-based multiplex assay. All lungs met traditional transplant criteria after EVLP. The partial pressure of arterial oxygen and physiologic lung function significantly improved (p<0.05). No pulmonary edema was formed, and histology demonstrated no evidence of acute lung injury. Interleukin (IL)-6, IL-8, granulocyte colony-stimulating factor, and monocyte chemotactic protein-1 were upregulated, while granulocyte macrophage colony-stimulating factor was downregulated during EVLP (p<0.05). IL-1β, IL-4, IL-7, IL-12, interferon-γ, macrophage inflammatory protein-1β, and tumor necrosis factor-α were detectable and unchanged. Ex-vivo lung perfusion demonstrates the ability to improve oxygenation and physiologic lung function in donor lungs unacceptable for transplantation without injury to the lung. We establish here a cytokine expression profile in human lungs undergoing normothermic EVLP. These data can be used in the future to explore novel targeted therapies for ischemia-reperfusion injury. Copyright © 2011 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  13. Visual anatomical lung CT scan assessment of lung recruitability.

    PubMed

    Chiumello, Davide; Marino, Antonella; Brioni, Matteo; Menga, Federica; Cigada, Irene; Lazzerini, Marco; Andrisani, Maria C; Biondetti, Pietro; Cesana, Bruno; Gattinoni, Luciano

    2013-01-01

    The computation of lung recruitability in acute respiratory distress syndrome (ARDS) is advocated to set positive end-expiratory pressure (PEEP) for preventing lung collapse. The quantitative lung CT scan, obtained by manual image processing, is the reference method but it is time consuming. The aim of this study was to evaluate the accuracy of a visual anatomical analysis compared with a quantitative lung CT scan analysis in assessing lung recruitability. Fifty sets of two complete lung CT scans of ALI/ARDS patients computing lung recruitment were analyzed. Lung recruitability computed at an airway pressure of 5 and 45 cm H(2)O was defined as the percentage decrease in the collapsed/consolidated lung parenchyma assessed by two expert radiologists using a visual anatomical analysis and as the decrease in not aerated lung regions using a quantitative analysis computed by dedicated software. Lung recruitability was 11.3 % (interquartile range 7.39-16.41) and 15.5 % (interquartile range 8.18-21.43) with the visual anatomical and quantitative analysis, respectively. In the Bland-Altman analysis, the bias and agreement bands between the visual anatomical and quantitative analysis were -2.9 % (-11.8 to +5.9 %). The ROC curve showed that the optimal cutoff values for the visual anatomical analysis in predicting high versus low lung recruitability was 8.9 % (area under the ROC curve 0.9248, 95 % CI 0.8550-0.9946). Considering this cutoff, the sensitivity, specificity, and diagnostic accuracy were 0.96, 0.76, and 0.86, respectively. Visual anatomical analysis can classify patients into those with high and low lung recruitability allowing more intensivists to get access to lung recruitability assessment.

  14. Pretreatment with perfluorohexane vapor attenuates fMLP-induced lung injury in isolated perfused rabbit lungs.

    PubMed

    Bleyl, Jörg U; Heller, Axel R; Fehrenbach, Antonia; Heintz, Manuel; Fehrenbach, Heinz; Klenz, Gesa; Gama de Abreu, Marcelo; Hübler, Matthias; Spieth, Peter M; Koch, Thea

    2010-08-01

    The authors investigated the protective effects and dose dependency of perfluorohexane (PFH) vapor on leukocyte-mediated lung injury in isolated, perfused, and ventilated rabbit lungs. Lungs received either 18 vol.% (n = 7), 9 vol.% (n = 7), or 4.5 vol.% (n = 7) PFH. Fifteen minutes after beginning of PFH application, lung injury was induced with formyl-Met-Leu-Phe (fMLP). Control lungs (n = 7) received fMLP only. In addition 5 lungs (PFH-sham) remained uninjured receiving 18 vol.% PFH only. Pulmonary artery pressure (mPAP), peak inspiratory pressure (P(max)), and lung weight were monitored for 90 minutes. Perfusate samples were taken at regular intervals for analysis and representative lungs were fixed for histological analysis. In the control, fMLP application led to a significant increase of mPAP, P(max), lung weight, and lipid mediators. Pretreatment with PFH attenuated the rise in these parameters. This was accompanied by preservation of the structural integrity of the alveolar architecture and air-blood barrier. In uninjured lungs, mPAP, P(max), lung weight, and lipid mediator formation remained uneffected in the presence of PFH. The authors concluded that pretreatment with PFH vapor leads to an attenuation of leukocyte-mediated lung injury. Vaporization of perfluorocarbons (PFCs) offers new therapeutic options, making use of their protective and anti-inflammatory properties in prophylaxis or in early treatment of acute lung injury.

  15. 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. © The Author(s) 2015.

  16. Ga lung scan has come to stay.

    PubMed

    Gianfranco, R; Franco, S

    1984-09-01

    Present status of Ga lung scan in sarcoidosis is reviewed: accumulation of radionuclide in the lung fields seems better quantified by computer methods; low doses (1.5 mCi) may be enough in the centres using subjective scoring methods; Ga positivity shown on four-view segmental maps of each lung could be useful in guiding BAL or lung biopsy. Ga lung scan appears more sensitive than both Chest X-ray and ACE in evaluating the response to therapy and in foreseeing relapses. The comparison with BAL is difficult due to the difficulty of comparing BAL data from different laboratories. Anyway, Ga, ACE and BAL are markers of different phenomena and all help our understanding of the disease and should guide our interventions. Ga scoring during steroid therapy has a strong clinical meaning only when positive, while negativity could be due to drug-induced uptake suppression.

  17. Bone metastasis on Tc99-m sestamibi myocardial perfusion scan

    PubMed Central

    Hatemi, Lachin; Jabi, Feraas

    2015-01-01

    A 75-year-old woman presented to our department for a stress myocardial perfusion imaging study with Tc99m-sestamibi. Incidental focal uptake, found in the left upper anterior chest, was initially felt to be located in the left breast. After additional single-photon CT imaging was performed the same day, extracardiac foci within the ribs, spine, and left lung (worrisome for active metastases) were shown to be present, with the initial focus located within a left rib rather than a breast. A review of previous radiographic and nuclear imaging studies confirmed metastatic disease from recurrent follicular thyroid cancer. Atypical focal extracardiac activity must be closely scrutinized for the possibility of malignancy, as Tc99m-sestamibi (in addition to being myocardium-avid) is tumor-avid. PMID:27190553

  18. 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

  19. Ex vivo lung perfusion allows successful transplantation of donor lungs from hanging victims.

    PubMed

    Bennett, Daine T; Reece, T Brett; Smith, Phillip D; Grandhi, Miral Sadaria; Rove, Jessica A Yu; Justison, George A; Mitchell, John D; Fullerton, David A; Zamora, Martin R; Weyant, Michael J

    2014-09-01

    Donor lungs acquired from victims of asphyxiation by hanging are not routinely used for lung transplantation because of the associated lung injury. Ex vivo lung perfusion (EVLP) is a technique to evaluate marginal donor lungs before transplantation. We report here our experience with the use of EVLP in donor lungs procured from victims of asphyxia by hanging. Lungs from 5 donors who became brain dead secondary to hanging were evaluated by EVLP. Donor organs were perfused according to trial protocol. Donor lungs were accepted for transplantation if they maintained a PaO2 greater than or equal to 350 mm Hg, had a clear roentgenogram, and had no significant worsening of physiologic metrics. Perfused organs included single and double lung blocs, and all were perfused without technical incident. Three of the 5 donor organs evaluated met criteria for transplantation after 3 hours of EVLP and were transplanted. Donor organs rejected for transplantation showed either signs of worsening PaO2 or deterioration of physiologic metrics. There were no intraoperative complications in the patients who underwent transplantation, and all were alive at 30 days. We report here the successful use of EVLP to assess donor lungs acquired from victims of asphyxiation by hanging. The use of EVLP in this particular group of donors has the potential to expand the available donor pool. We demonstrate that EVLP is a viable option for evaluating the function of lung allografts before transplantation and would recommend that all donor lungs obtained from hanging victims undergo EVLP to assess their suitability for transplantation. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Reconditioning of lungs donated after circulatory death with normothermic ex vivo lung perfusion.

    PubMed

    Nakajima, Daisuke; Chen, Fengshi; Yamada, Tetsu; Sakamoto, Jin; Ohsumi, Akihiro; Bando, Toru; Date, Hiroshi

    2012-02-01

    The use of donation-after-circulatory-death (DCD) donors for lung transplantation has come into practice. In this study we investigated whether DCD lungs can be resuscitated after warm ischemia with normothermic ex vivo lung perfusion (EVLP). Four hours after cardiac arrest, beagle dogs were divided into two groups (n = 6 each): those with static cold storage (SCS group) and those with normothermic EVLP (EVLP group), for 3.5 hours. Physiologic lung functions were evaluated during EVLP. In both groups, the left lungs were then transplanted and reperfused for 4 hours to evaluate post-transplant lung functions. Lung tissue adenosine triphosphate (ATP) levels were measured at given time-points. Lung oxygenation was significantly improved with EVLP (p < 0.01), and lung oxygenation at the end of EVLP significantly reflected post-transplant lung oxygenation (r = 0.99, p < 0.01). Post-transplant lung oxygenation was significantly better in the EVLP group than in the SCS group (p < 0.05). Both dynamic pulmonary compliance and wet-to-dry lung weight ratio 4 hours after transplantation were also significantly better in the EVLP group than in the SCS group (p < 0.05). Microthrombi in the donor lungs before transplantation were microscopically detected more often in the SCS group. The lung tissue ATP levels 4 hours after transplantation were significantly higher in the EVLP group compared with the SCS group (p = 0.03). Normothermic ex vivo lung perfusion could resuscitate DCD lungs injured by warm ischemia, and may ameliorate ischemia-reperfusion injury. Copyright © 2012 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  1. Extravascular Lung Water and Tissue Perfusion Biomarkers After Lung Resection Surgery Under a Normovolemic Fluid Protocol.

    PubMed

    Assaad, Sherif; Kyriakides, Tassos; Tellides, George; Kim, Anthony W; Perkal, Melissa; Perrino, Albert

    2015-08-01

    The optimal fluid management for lung resection surgery remains undefined. Concern related to postoperative pulmonary edema has led to the practice of fluid restriction. This practice risks hypovolemia and tissue hypoperfusion. The authors examined the extravascular lung water accumulation and tissue perfusion biomarkers under protective lung ventilation and normovolemia. A prospective observational study. A single-center study. Forty patients aged 18 years or older undergoing lung resection surgery. Patients were maintained on protective lung ventilation and a normovolemic fluid protocol. Hemodynamic variables, including global end-diastolic volume index, cardiac index, and extravascular lung water index, together with tissue perfusion biomarkers, including serum creatinine, lactic acid, central venous oxygen saturation, and brain natriuretic peptide, were measured perioperatively. Parametric or nonparametric techniques were used to assess changes of these parameters over 72 hours postoperatively. The global end-diastolic volume index was maintained; cardiac index was increased, without a significant change in extravascular lung water index. Acute kidney injury based on AKIN criteria occurred in 3 patients (7.5%), and in 1 patient (2.5 %) based on RIFLE criteria. Lactic acid and central venous oxygen saturation remained within normal limits, and brain natriuretic peptide showed an insignificant increase. In patients undergoing lesser lung resections, a fluid protocol targeting normovolemia together with protective lung ventilation did not increase extravascular lung water. These results suggest further study to identify the optimal fluid regimen to mitigate pulmonic and extrapulmonic complications after lung resection. Published by Elsevier Inc.

  2. First in vivo magnetic particle imaging of lung perfusion in rats.

    PubMed

    Zhou, Xinyi Yedda; Jeffris, Kenneth; Yu, Elaine; Zheng, Bo; Goodwill, Patrick; Nahid, Payam; Conolly, Steven

    2017-02-20

    Pulmonary embolism (PE), along with the closely related condition of deep vein thrombosis, affect an estimated 600,000 patients in the US per year. Untreated, PE carries a mortality rate of 30%. Because many patients experience mild or non-specific symptoms, imaging studies are necessary for definitive diagnosis of PE. Iodinated CT pulmonary angiography (CTPA) is recommended for most patients, while nuclear medicine-based ventilation/perfusion (V/Q) scans are reserved for patients in whom the use of iodine is contraindicated. Magnetic particle imaging (MPI) is an emerging tracer imaging modality with high image contrast (no tissue background signal) and sensitivity (200 nM Fe) to superparamagnetic iron oxide (SPIO) tracer. Importantly, unlike CT or nuclear medicine, MPI uses no ionizing radiation. Further, MPI is not derived from magnetic resonance imaging (MRI); MPI directly images SPIO tracers via their strong electronic magnetization, enabling deep imaging of anatomy including within the lungs, which is very challenging with MRI. Here, the first high-contrast in vivo MPI lung perfusion images of rats are shown using a novel lung perfusion agent, MAA-SPIOs.

  3. First in vivo magnetic particle imaging of lung perfusion in rats

    NASA Astrophysics Data System (ADS)

    Zhou, Xinyi Y.; Jeffris, Kenneth E.; Yu, Elaine Y.; Zheng, Bo; Goodwill, Patrick W.; Nahid, Payam; Conolly, Steven M.

    2017-05-01

    Pulmonary embolism (PE), along with the closely related condition of deep vein thrombosis, affect an estimated 600 000 patients in the US per year. Untreated, PE carries a mortality rate of 30%. Because many patients experience mild or non-specific symptoms, imaging studies are necessary for definitive diagnosis of PE. Iodinated CT pulmonary angiography is recommended for most patients, while nuclear medicine-based ventilation/perfusion (V/Q) scans are reserved for patients in whom the use of iodine is contraindicated. Magnetic particle imaging (MPI) is an emerging tracer imaging modality with high image contrast (no tissue background signal) and sensitivity to superparamagnetic iron oxide (SPIO) tracer. Importantly, unlike CT or nuclear medicine, MPI uses no ionizing radiation. Further, MPI is not derived from magnetic resonance imaging (MRI); MPI directly images SPIO tracers via their strong electronic magnetization, enabling deep imaging of anatomy including within the lungs, which is very challenging with MRI. Here, the first high-contrast in vivo MPI lung perfusion images of rats are shown using a novel lung perfusion agent, MAA-SPIOs.

  4. Ventilation/perfusion mismatch during lung aeration at birth.

    PubMed

    Lang, Justin A R; Pearson, James T; te Pas, Arjan B; Wallace, Megan J; Siew, Melissa L; Kitchen, Marcus J; Fouras, Andreas; Lewis, Robert A; Wheeler, Kevin I; Polglase, Graeme R; Shirai, Mikiyasu; Sonobe, Takashi; Hooper, Stuart B

    2014-09-01

    At birth, the transition to newborn life is triggered by lung aeration, which stimulates a large increase in pulmonary blood flow (PBF). Current theories predict that the increase in PBF is spatially related to ventilated lung regions as they aerate after birth. Using simultaneous phase-contrast X-ray imaging and angiography we investigated the spatial relationships between lung aeration and the increase in PBF after birth. Six near-term (30-day gestation) rabbits were delivered by caesarean section, intubated and an intravenous catheter inserted, before they were positioned for X-ray imaging. During imaging, iodine was injected before ventilation onset, after ventilation of the right lung only, and after ventilation of both lungs. Unilateral ventilation increased iodine levels entering both left and right pulmonary arteries (PAs) and significantly increased heart rate, iodine ejection per beat, diameters of both left and right PAs, and number of visible vessels in both lungs. Within the 6th intercostal space, the mean gray level (relative measure of iodine level) increased from 68.3 ± 11.6 and 70.3 ± 7.5%·s to 136.3 ± 22.6 and 136.3 ± 23.7%·s in the left and right PAs, respectively. No differences were observed between vessels in the left and right lungs, despite the left lung not initially being ventilated. The increase in PBF at birth is not spatially related to lung aeration allowing a large ventilation/perfusion mismatch, or pulmonary shunting, to occur in the partially aerated lung at birth.

  5. Technetium-fibrinogen lung scanning in canine lung contusion

    SciTech Connect

    Geller, E.; Khaw, B.A.; Strauss, H.W.; Carvalho, A.C.; Rajagopalan, B.; Jones, R.; Zapol, W.M.

    1984-07-01

    To detect experimentally induced acute lung contusion in anesthetized dogs, serial radionuclide images of the lung were recorded following intravenous infusion of 99mTc-labelled human fibrinogen (Tc-HF). The accumulation of Tc-HF in canine lungs was serially quantitated for up to 20 hours after lung contusion. A contusion (number1) was produced in one lung, Tc-HF was injected IV after 15 minutes, and 75 minutes later a contralateral lung contusion (number2) was produced in a series of 14 dogs. At autopsy the excised lungs were scanned, sectioned, and counted for radioactivity. Radiolabelled fibrinogen accumulated within 2-4 minutes of contusion number2 and remained stable over the next 20 hours in 14 dogs; contusion number1 was barely visible in four dogs. Lung Tc-HF activity in the central region of contusion number2 remained sixfold higher than in normal lung tissue. These data suggest that following lung contusion, fibrinogen deposition occurs rapidly and remains stable over a 20-hour interval of observation.

  6. Differential pulmonary perfusion scan after percutaneous occlusion of the patent ductus arteriosus: one-decade consecutive longitudinal study from a single institution.

    PubMed

    Kramoh, Euloge Kouadio; Miró, Joaquim; Bigras, Jean-Luc; Turpin, Sophie; Lambert, Raymond; Lapierre, Chantal; Jin, Weidong; Dahdah, Nagib

    2008-09-01

    Reduced left lung perfusion has been described following percutaneous occlusion of the patent ductus arteriosus (PDA). We aimed to identify the incidence of lung perfusion abnormalities and the associated risk factors in our consecutive series. Between November 1994 and December 2003, 150 procedures were performed on 145 patients, age 4.6 +/- 4 years. Gianturco coil was used in 88.2%, Amplatzer duct occluder in 6.7%, and Rashkind Umbrella in 5.5%. Lung perfusion scan was scheduled within 48 h (LPS-1), at 6-12 months (LPS-2) and later (LPS-3) in the case of persistent abnormalities. Left lung perfusion <40% was considered abnormal. LPS-1 was obtained in 95.8% and was abnormal in 31%. LPS-2, available in 48.2%, returned to normal in 65.7% (p < 0.001). LPS-3, required in 6.2%, was normal in 55.6% (p = 0.07). Identifiable risk factors were low age and height (p < 0.01), higher Q(p)/Q(s) ratio (p < 0.05), and larger PDA size indexed for height (p < 0.001) or body surface area (p < 0.01). The number of coils or loops deployed in the pulmonary end of the PDA did not influence lung perfusion. In conclusion, we describe a high incidence of left lung perfusion reduction following percutaneous PDA occlusion, more likely in the young with large PDA. However, spontaneous recovery usually occurs within a few months.

  7. 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

  8. Lung transplantation from donors after circulatory death using portable ex vivo lung perfusion

    PubMed Central

    Bozso, Sabin; Vasanthan, Vishnu; Luc, Jessica GY; Kinaschuk, Katie; Freed, Darren; Nagendran, Jayan

    2015-01-01

    BACKGROUND: Donation after circulatory death is a novel method of increasing the number of donor lungs available for transplantation. Using organs from donors after circulatory death has the potential to increase the number of transplants performed. METHODS: Three bilateral lung transplants from donors after circulatory death were performed over a six-month period. Following organ retrieval, all sets of lungs were placed on a portable ex vivo lung perfusion device for evaluation and preservation. RESULTS: Lung function remained stable during portable ex vivo perfusion, with improvement in partial pressure of oxygen/fraction of inspired oxygen ratios. Mechanical ventilation was discontinued within 48 h for each recipient and no patient stayed in the intensive care unit longer than eight days. There was no postgraft dysfunction at 72 h in two of the three recipients. Ninety-day mortality for all recipients was 0% and all maintain excellent forced expiratory volume in 1 s and forced vital capacity values post-transplantation. CONCLUSION: The authors report excellent results with their initial experience using donors after circulatory death after portable ex vivo lung perfusion. It is hoped this will allow for the most efficient use of available donor lungs, leading to more transplants and fewer deaths for potential recipients on wait lists. PMID:25379654

  9. 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

  10. Histologic and functional evaluation of lungs reconditioned by ex vivo lung perfusion.

    PubMed

    Medeiros, Israel Lopes; Pêgo-Fernandes, Paulo Manuel; Mariani, Alessandro Wasum; Fernandes, Flávio Guimarães; do Vale Unterpertinger, Fernando; Canzian, Mauro; Jatene, Fabio Biscegli

    2012-03-01

    Only about 15% of donor lungs are considered suitable for transplantation (LTx). Ex vivo lung perfusion (EVLP) has been developed as a method to reassess and repair damaged lungs. We report our experience with EVLP in non-acceptable donor lungs and evaluate its ability to recondition these lungs. We studied lungs from 16 brain-dead donors rejected for LTx. After harvesting, the lungs were stored at 4°C for 10 hours and subjected to normothermic EVLP with Steen Solution (Vitrolife, Göteborg, Sweden) for 60 minutes. For functional evaluation, the following variables were assessed: partial pressure of arterial oxygen (Pao(2)), pulmonary vascular resistance (PVR), and lung compliance (LC). For histologic assessment, lung biopsy was done before harvest and after EVLP. Tissue samples were examined under light microscopy. To detect and quantify apoptosis, terminal deoxynucleotide transferase-mediated deoxy uridine triphosphate nick-end labeling assay was used. Thirteen lung donors were refused for having impaired lung function. The mean Pao(2) obtained in the organ donor at the referring hospital was 193.7 mm Hg and rose to 489 mm Hg after EVLP. During EVLP, the mean PVR was 652.5 dynes/sec/cm(5) and the mean LC was 48 ml/cm H(2)O. There was no significant difference between the mean Lung Injury Score before harvest and after EVLP. There was a trend toward a reduction in the median number of apoptotic cells after EVLP. EVLP improved lung function (oxygenation capacity) of organs considered unsuitable for transplantation. Lung tissue structure did not deteriorate even after 1 hour of normothermic perfusion. Copyright © 2012 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.

  11. Ex Vivo Lung Perfusion: A Key Tool for Translational Science in the Lungs.

    PubMed

    Tane, Shinya; Noda, Kentaro; Shigemura, Norihisa

    2017-02-23

    Ex vivo lung perfusion (EVLP) promises to be a comprehensive platform for assessment, re-conditioning, and preservation for donor lungs and has been dramatically changing the face of clinical lung transplantation. Besides its increasing role in lung transplantation, EVLP has also been recognized as a useful tool for translational research involving the lungs. Based on recent remarkable evidence and experience using EVLP in lung transplantation, there is growing interest in and expectations for the use of EVLP beyond the field of lung transplantation. By combining EVLP with advances in regenerative medicine, stem cell biology, and oncology, the evolving technology of EVLP has a tremendous potential to advance pulmonary medicine and science. In this review, we revisit recent advances in EVLP technology and research and discuss the future translation of EVLP applications into life-changing medicine.

  12. Factors determining altered perfusion after acute pulmonary embolism assessed by quantified single-photon emission computed tomography-perfusion scan

    PubMed Central

    Meysman, Marc; Everaert, Hendrik; Vincken, Walter

    2017-01-01

    AIM OF THE STUDY: The aim of the study was to analyze the evolution of perfusion (Q)-defects in patients treated for acute pulmonary embolism (PE), correlation with baseline parameters and evaluation of recurrence risk. METHODS: This is a single-center prospective observational cohort study in symptomatic normotensive PE. Comparison of the ventilation/perfusion single-photon emission computed tomography (V/Q-SPECT) acquired at baseline with a quantified SPECT (Q-SPECT) repeated at 1 week and 6 months. The Q-defect extent (percentage of total lung volume affected) was measured semiquantitatively. Data collected at baseline were age, gender, body mass index (BMI), history of previous venous thromboembolism (HVTE), Charlson's Comorbidity Score (CcS), plasma troponin-T and D-dimer levels, PE Severity Index, and tricuspid regurgitation jet (TRJ) velocity. RESULTS: Forty-six patients (22 men/24 women, mean age 61.7 years (± standard deviation 16.3)) completed the study. At 1 week, 13/46 (28.3 %) and at 6 months 22/46 (47.8%) patients had completely normalized Q-SPECT. Persistence of Q-defects was more frequent in female patients in univariate and multivariate analysis. We found no correlation between the persistence of Q-defects on Q-SPECT and HVTE, BMI, plasma troponin-T, and CcS. However, lower TRJ and younger age were statistically significantly linked to normalization of Q-scans after 6 months of treatment only in univariate analysis. There is no difference in the frequency of recurrent PE in relation to the persistence of Q-defects. CONCLUSION: Acute PE patients of female, older age, and higher TRJ in univariate analysis and patients of female in multivariate analysis seem to have a higher risk of persistent Q-defects after 6 months treatment. The presence of residual Q-abnormalities at 6 months was not associated with an increased risk for recurrent PE. PMID:28197219

  13. 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

  14. Intermediate probability lung scans (IPLS): retrospective review of 82 cases.

    PubMed

    Wong, W Y; Ng, D C; Ang, E S; Goh, A S; Sundram, F X

    2001-10-01

    In the light of a reported 30-40% prevalence of pulmonary embolism (PE) in intermediate probability lung scans (IPLS) based on results of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study, we examined the frequency of documented PE in 82 patients with IPLS, the management strategy employed in these patients with regards to additional imaging (e.g. further evaluation with venous sonography or spiral computed tomographic angiography (CTA)), anticoagulation therapy, and subsequent follow-up outcomes. Retrospective review of the medical records of 82 patients with intermediate probability ventilation-perfusion (V/Q) lung scans from January 1998 to July 1999. 14.1% of V/Q scans were reported as having an intermediate probability of PE. 72% of IPLS were subject to further evaluation with venous Doppler ultrasound and/or CTA, and 39% of these patients had evidence of thrombo-embolic disease. All patients with imaging evidence of thromboembolic disease were started on anticoagulation therapy. In addition, 19 patients were treated based on clinical judgement. Amongst the 35 patients who were not treated, 17 (49%) were based on clinical findings without further imaging. There was no mortality on follow-up of 28 cases of untreated IPLS. The majority of IPLS will have further imaging, out of which over one-third will have thrombo-embolic disease. Approximately half of IPLS cases will receive anticoagulation therapy. No mortality or PE was found on follow-up of patients who were not treated.

  15. 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.

  16. Acute kidney injury after ex vivo lung perfusion (EVLP).

    PubMed

    Hauck, J; Osho, A; Castleberry, A; Hartwig, M; Reddy, L; Phillips-Bute, B; Swaminathan, M; Mathew, J; Stafford-Smith, M

    2014-12-01

    Ex vivo lung perfusion (EVLP) identifies viability for marginal organs but complicates and lengthens lung transplantation surgery. Preliminary evidence supports equivalency for EVLP-assisted versus traditional (non-EVLP) procedures regarding graft function, postoperative course, mortality, and survival. However, acute kidney injury (AKI), a common serious complication of lung transplantation, has not been assessed. We tested the hypothesis that EVLP-assisted and non-EVLP lung transplantations are associated with different AKI rates. Demographic, procedural, and renal data were gathered for 13 EVLP-viable lung transplantations and a non-EVLP group matched 4:1 for single versus double, pulmonary disease, and age. AKI was defined by AKI Network (AKIN) criteria and peak creatinine rise relative to baseline (Δ%Cr) during the 1st 10 postoperative days. Chi-square was performed for AKIN and 2-tailed t test for %ΔCr. Patient and procedural characteristics were similar between the groups. One non-EVLP patient required postoperative dialysis. AKI rates were also similar, as assessed by both AKIN (EVLP 7/13 (54%) vs non-EVLP 32/52 (62%); P = .61) and %ΔCr (EVLP 91 ± 81% vs non-EVLP 72 ± 62%; P = .63). We did not observe different AKI rates between EVLP-assisted and traditional lung transplant procedures. Although 1 non-EVLP patient required dialysis, AKI rates were otherwise similar. These findings further support EVLP as a strategy to expand the organ pool and reduce concerns for high-renal risk recipients. The small sample size and retrospective design are limitations. However, our sample size is similar to other reports, and it is the first to analyze AKI after EVLP-assisted lung transplantation. Larger multicenter prospective studies are needed. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Alternative solution for ex vivo lung perfusion, experimental study on donated human lungs non-accepted for transplantation.

    PubMed

    Fernandes, Lucas Matos; Mariani, Alessandro Wasum; Medeiros, Israel Lopes de; Samano, Marcos Naoyuki; Abdalla, Luís Gustavo; Correia, Aristides Tadeu; Nepomuceno, Natália Aparecida; Canzian, Mauro; Pêgo-Fernandes, Paulo Manuel

    2015-05-01

    To evaluate a new perfusate solution to be used for ex vivo lung perfusion. Randomized experimental study using lungs from rejected brain-dead donors harvested and submitted to 1 hour of ex vivo lung perfusion (EVLP) using mainstream solution or the alternative. From 16 lungs blocs tested, we found no difference on weight after EVLP: Steen group (SG) = 1,097±526g; Alternative Perfusion Solution (APS) = 743±248g, p=0.163. Edema formation, assessed by Wet/dry weigh ratio, was statistically higher on the Alternative Perfusion Solution group (APS = 3.63 ± 1.26; SG = 2.06 ± 0.28; p = 0.009). No difference on PaO2 after EVLP (SG = 498±37.53mmHg; APS = 521±55.43mmHg, p=0.348, nor on histological analyses: pulmonary injury score: SG = 4.38±1.51; APS = 4.50±1.77, p=0.881; apoptotic cells count after perfusion: SG = 2.4 ± 2.0 cells/mm2; APS = 4.8 ± 6.9 cells/mm2; p = 0.361). The ex vivo lung perfusion using the alternative perfusion solution showed no functional or histological differences, except for a higher edema formation, from the EVLP using Steen Solution(r) on lungs from rejected brain-dead donors.

  18. Correlation of iodine uptake and perfusion parameters between dual-energy CT imaging and first-pass dual-input perfusion CT in lung cancer.

    PubMed

    Chen, Xiaoliang; Xu, Yanyan; Duan, Jianghui; Li, Chuandong; Sun, Hongliang; Wang, Wu

    2017-07-01

    To investigate the potential relationship between perfusion parameters from first-pass dual-input perfusion computed tomography (DI-PCT) and iodine uptake levels estimated from dual-energy CT (DE-CT).The pre-experimental part of this study included a dynamic DE-CT protocol in 15 patients to evaluate peak arterial enhancement of lung cancer based on time-attenuation curves, and the scan time of DE-CT was determined. In the prospective part of the study, 28 lung cancer patients underwent whole-volume perfusion CT and single-source DE-CT using 320-row CT. Pulmonary flow (PF, mL/min/100 mL), aortic flow (AF, mL/min/100 mL), and a perfusion index (PI = PF/[PF + AF]) were automatically generated by in-house commercial software using the dual-input maximum slope method for DI-PCT. For the dual-energy CT data, iodine uptake was estimated by the difference (λ) and the slope (λHU). λ was defined as the difference of CT values between 40 and 70 KeV monochromatic images in lung lesions. λHU was calculated by the following equation: λHU = |λ/(70 - 40)|. The DI-PCT and DE-CT parameters were analyzed by Pearson/Spearman correlation analysis, respectively.All subjects were pathologically proved as lung cancer patients (including 16 squamous cell carcinoma, 8 adenocarcinoma, and 4 small cell lung cancer) by surgery or CT-guided biopsy. Interobserver reproducibility in DI-PCT (PF, AF, PI) and DE-CT (λ, λHU) were relatively good to excellent (intraclass correlation coefficient [ICC]Inter = 0.8726-0.9255, ICCInter = 0.8179-0.8842; ICCInter = 0.8881-0.9177, ICCInter = 0.9820-0.9970, ICCInter = 0.9780-0.9971, respectively). Correlation coefficient between λ and AF, and PF were as follows: 0.589 (P < .01) and 0.383 (P < .05). Correlation coefficient between λHU and AF, and PF were as follows: 0.564 (P < .01) and 0.388 (P < .05).Both the single-source DE-CT and dual-input CT perfusion analysis method can be applied to

  19. Effects of Constant Flow vs. Constant Pressure Perfusion on Fluid Filtration in Severe Hypothermic Isolated Blood-Perfused Rat Lungs.

    PubMed

    Halsøy, Kathrine; Kondratiev, Timofey; Tveita, Torkjel; Bjertnaes, Lars J

    2016-01-01

    Victims of severe accidental hypothermia are prone to fluid extravasation but rarely develop lung edema. We hypothesize that combined hypothermia-induced increase in pulmonary vascular resistance (PVR) and a concomitant fall in cardiac output protect the lungs against edema development. Our aim was to explore in hypothermic-isolated blood-perfused rat lungs whether perfusion at constant pressure influences fluid filtration differently from perfusion at constant flow. Isolated blood-perfused rat lungs were hanging freely in a weight transducer for measuring weight changes (ΔW). Fluid filtration coefficient (Kfc), was determined by transiently elevating left atrial pressure (Pla) by 5.8 mmHg two times each during normothermia (37°C) and during hypothermia (15°C). The lung preparations were randomized to two groups. One group was perfused with constant flow (Constant flow group) and the other group with constant pulmonary artery pressure (Constant PPA group). Microvascular pressure (Pmv) was determined before and during elevation of Pla (ΔPmv) by means of the double occlusion technique. Kfc was calculated with the formula Kfc = ΔW/ΔPmv/min. All Kfc values were normalized to predicted lung weight (PLW), which was based on body weight (BW) according to the formula: PLW = 0.0053 BW - 0.48 and presented as KfcPLW in mg/min/mmHg/g. At cessation, bronchoalveolar lavage (BAL) fluid/perfusate protein concentration (B/P) ratio was determined photometrically. Data were analyzed with parametric or non-parametric tests as appropriate. p < 0.05 considered as significant. Perfusate flow remained constant in the Constant flow group, but was more than halved during hypothermia in the Constant PPA group concomitant with a more fold increase in PVR. In the Constant flow group, KfcPLW and B/P ratio increased significantly by more than 10-fold during hypothermia concerted by visible signs of edema in the trachea. Hemoglobin and hematocrit increased within the

  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. Uptake of exogenous spermidine by rat lungs perfused in situ

    SciTech Connect

    Rannels, D.E.; Addison, J.L.

    1987-01-01

    Uptake of the polyamine spermidine (SPD) from the pulmonary circulation was characterized by using ventilated rat lungs perfused in situ with Krebs-Henseleit-bicarbonate buffer containing 4.5% bovine serum albumin, 5.6 mM glucose, and 20 amino acids at plasma levels. (/sup 14/C)SPD was accumulated by the lungs in a time- and concentration-dependent manner. The pathway of SPD uptake exhibited saturation kinetics with an apparent K/sub m/ in the range of 1 ..mu..M and a V/sub max/ of 450-540 pmol/g lung min. SPD uptake was inhibited by the naturally occurring polyamines putrescine and spermine (SPM) and by the inhibitor of polyamine synthesis, methyglyoxal bis(guanylhydrazone) (MGBG). Inhibition of SPD uptake by SPM followed competitive kinetics; although MGBG was also a competitive inhibitor of SPD uptake, MGBG was less effective than SPM. These observations indicate that SPD is taken up from the pulmonary circulation by a carrier-mediated pathway that is inhibited by other natural polyamines and by MGBG and exhibits by other natural polyamines and by MGBG and exhibits substrate affinity in the range of plasma SPD concentrations.

  2. Scintillation Scanning of Lungs in Preoperative Assessment of Carcinoma of Bronchus

    PubMed Central

    Walker, R. H. Secker; Provan, J. L.

    1969-01-01

    Lung scans with the use of macroaggregated human serum albumin labelled with technetium-99m were carried out in 52 patients before thoracotomy. Forty-three patients had carcinoma of the bronchus. Tumours less than 2 cm. in diameter on the chest radiograph were not detected. Larger tumours showed defects in perfusion, ranging in size from the mass seen on the chest radiograph to almost absent perfusion of the entire lung. The extent of the defect in perfusion was closely related to involvement of the pulmonary vessels at the hilum by distortion, compression, or invasion by the tumour. Bronchial obstruction played a less important part in producing the defects. The larger the defect in perfusion the greater was the involvement of the hilar and mediastinal structures and the more extensive was the surgery required. When perfusion of the affected lung was less than one-third of the total the tumour was found to be unresectable. ImagesFig. 1Fig. 2Fig. 3Fig. 4 PMID:5800342

  3. Initial experience of dual-energy lung perfusion CT using a dual-source CT system in children.

    PubMed

    Goo, Hyun Woo

    2010-09-01

    Initial experience of dual-source dual-energy (DE) lung perfusion CT in children is described. In addition to traditional identification of pulmonary emboli, the assessment of lung perfusion is technically feasible with dual-source DE CT in children with acceptable radiation dose. This article describes how to perform dual-source DE lung perfusion CT in children, including the optimization of intravenous injection method and CT dose parameters. How to produce weighted-average CT images for the assessment of pulmonary emboli and colour-coded perfusion maps for the assessment of regional lung perfusion is also detailed. Lung perfusion status can then be evaluated on perfusion maps by means of either qualitative or quantitative analysis. Potential advantages and disadvantages of this emerging CT technique compared to lung perfusion scintigraphy and cardiac MRI are discussed.

  4. Improved diagnostic accuracy of lung perfusion imaging using Tc-99m MAA SPECT

    SciTech Connect

    O'Donnell, J.K.; Golish, J.A.; Go, R.T.; Risius, B.; Graor, R.A.; MacIntyre, W.J.; Feiglin, D.H.

    1984-01-01

    The addition of emission tomography (SPECT) to pulmonary perfusion imaging should improve diagnostic accuracy by detecting perfusion defects otherwise masked by superimposition of normal lung activity and by reducing problems with interpretation of defects that result from overlying soft tissue or pleural effusions. In order to examine the contribution of SPECT in the scintigraphic evaluation for pulmonary embolus (PE), the authors have obtained both planar and SPECT studies in 94 cases of suspected PE. All studies employed 3-4 mCi of Tc-99m MAA and standard six-view planar image acquisition. SPECT raw data of 64 images were then acquired over a 360 degree transaxial rotation with subsequent computer reconstruction. Xe-133 ventilation studies were performed when clinically indicated and tolerated by the patient. For 19 studies angiographic (AN) correlation was obtained within 24 hours. In 16/19 planar and SPECT both gave a high probability of PE but SPECT gave better segmental localization and showed better agreement with the number of defects seen at AN. In 3 indeterminate planar scans, 2 were low probability with SPECT and had negative AN. The third, a patient with Wegener's vasculitis, remained indeterminate with SPECT and had negative AN. Five patients with PE had repeat planar/SPECT/AN studies to evaluate response to treatment. SPECT correlated better with AN findings in each case. The authors conclude that SPECT perfusion imaging provides better anatomic accuracy for defects representing PE and is the non-invasive technique of choice for documenting response to therapy.

  5. 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)

  6. Optimal Computed Tomographic Perfusion Scan Duration for Assessment of Acute Stroke Lesion Volumes.

    PubMed

    Kasasbeh, Aimen S; Christensen, Søren; Straka, Matus; Mishra, Nishant; Mlynash, Michael; Bammer, Roland; Albers, Gregory W; Lansberg, Maarten G

    2016-12-01

    The minimal scan duration needed to obtain reliable lesion volumes with computed tomographic perfusion (CTP) has not been well established in the literature. We retrospectively assessed the impact of gradual truncation of the scan duration on acute ischemic lesion volume measurements. For each scan, we identified its optimal scan time, defined as the shortest scan duration that yields measurements of the ischemic lesion volumes similar to those obtained with longer scanning, and the relative height of the fitted venous output function at its optimal scan time. We analyzed 70 computed tomographic perfusion scans of acute stroke patients. An optimal scan time could not be determined in 11 scans (16%). For the other 59 scans, the median optimal scan time was 32.7 seconds (90th percentile 52.6 seconds; 100th percentile 68.9 seconds), and the median relative height of the fitted venous output function at the optimal scan times was 0.39 (90th percentile 0.02; 100th percentile 0.00). On the basis of a linear model, the optimal scan time was T0 plus 1.6 times the width of the venous output function (P<0.001; R(2)=0.49). This study shows how the optimal duration of a computed tomographic perfusion scan relates to the arrival time and width of the contrast bolus. This knowledge can be used to optimize computed tomographic perfusion scan protocols and to determine whether a scan is of sufficient duration. Provided a baseline (T0) of 10 seconds, a total scan duration of 60 to 70 seconds, which includes the entire downslope of the venous output function in most patients, is recommended. © 2016 American Heart Association, Inc.

  7. 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.

  8. Lung Perfusion and Ventilation During Cardiopulmonary Bypass Reduces Early Structural Damage to Pulmonary Parenchyma.

    PubMed

    Freitas, Claudia Regina da Costa; Malbouisson, Luiz Marcelo Sa; Benicio, Anderson; Negri, Elnara Marcia; Bini, Filipe Minussi; Massoco, Cristina Oliveira; Otsuki, Denise Aya; Melo, Marcos Francisco Vidal; Carmona, Maria Jose Carvalho

    2016-04-01

    It is unclear whether maintaining pulmonary perfusion and ventilation during cardiopulmonary bypass (CPB) reduces pulmonary inflammatory tissue injury compared with standard CPB where the lungs are not ventilated and are minimally perfused. In this study, we tested the hypothesis that maintenance of lung perfusion and ventilation during CPB decreases regional lung inflammation, which may result in less pulmonary structural damage. Twenty-seven pigs were randomly allocated into a control group only submitted to sternotomy (n = 8), a standard CPB group (n = 9), or a lung perfusion group (n = 10), in which lung perfusion and ventilation were maintained during CPB. Hemodynamics, gas exchanges, respiratory mechanics, and systemic interleukins (ILs) were determined at baseline (T0), at the end of 90 minutes of CPB (T90), and 180 minutes after CPB (T180). Bronchoalveolar lavage (BAL) ILs were obtained at T0 and T180. Dorsal and ventral left lung tissue samples were examined for optical and electron microscopy. At T90, there was a transient reduction in PaO2/FIO2 in CPB (126 ± 64 mm Hg) compared with the control and lung perfusion groups (296 ± 46 and 244 ± 57 mm Hg; P < 0.001), returning to baseline at T180. Serum ILs were not different among the groups throughout the study, whereas there were significant increases in BAL IL-6 (P < 0.001), IL-8 (P < 0.001), and IL-10 (P < 0.001) in both CPB and lung perfusion groups compared with the control group. Polymorphonuclear counts within the lung tissue were smaller in the lung perfusion group than in the CPB group (P = 0.006). Electron microscopy demonstrated extrusion of surfactant vesicles into the alveolar spaces and thickening of the alveolar septa in the CPB group, whereas alveolar and capillary histoarchitecture was better preserved in the lung perfusion group. Maintenance of lung perfusion and ventilation during CPB attenuated early histologic signs of pulmonary inflammation and injury compared with standard CPB

  9. Usefulness of lung perfusion scintigraphy before lung cancer resection in patients with ventilatory obstruction.

    PubMed

    Mineo, Tommaso C; Schillaci, Orazio; Pompeo, Eugenio; Mineo, Davide; Simonetti, Giovanni

    2006-11-01

    The study was conducted to evaluate the efficacy of preoperative lung perfusion scintigraphy performed by planar acquisition and single-photon emission computed tomography (SPECT) in predicting postoperative pulmonary function of patients with resectable lung cancer and obstructive ventilatory defect. The study enrolled 39 patients (mean age, 67 +/- 2.1 years). All patients underwent preoperative and postoperative pulmonary function tests. Cut-off values for postoperative forced expiratory volume in 1 second (FEV1) were 65% of the predicted value for pneumonectomy and 45% for lobectomy. A semiquantitative analysis of planar and SPECT lung perfusion scintigraphy images was performed preoperatively to estimate postoperative predicted FEV1 (FEV1ppo). Relationships between FEV1ppo and measured postoperative FEV1 were tested by the Pearson correlation and Bland Altman agreement tests. Twenty-eight lobectomies and 11 pneumonectomies were performed. The FEV1ppo estimated by mean planar lung scintigraphy was 1.85 +/- 0.38 L, with a Pearson correlation coefficient to the measured FEV1 of 0.8632 (p < 0.001). The mean FEV1ppo estimated by SPECT was 1.78 +/- 0.31 L, with a Pearson coefficient to the measured FEV1 of 0.8527 (p < 0.001). Both values showed a more significant correlation with postoperative measured FEV1 after lobectomy (p < 0.001) than after pneumonectomy (p = 0.045). The Bland Altman test confirmed satisfactory agreement of FEV1ppo estimated by both planar lung scintigraphy and SPECT with FEV1 measured by spirometry. Both planar lung scintigraphy and SPECT can accurately predict postoperative FEV1 and can therefore be considered reliable tools in establishing operability of patients with lung cancer and ventilatory obstruction.

  10. The stripe sign: correlation of radionuclide ventilation and perfusion with He-3 magnetic resonance lung imaging

    PubMed

    Teates; Brookeman; Daniel; Truwit; Parekh; Mugler; de Lange EE

    1999-10-01

    PURPOSE: The aim of this study was to correlate regional ventilation and perfusion images and perfusion SPECT with images made using a newly developed magnetic resonance ventilation (MRV) method. MATERIALS AND METHODS: The investigation included a single patient with chronic obstructive pulmonary disease and a healthy control participant. Ventilation and perfusion images using Xe-133 and Tc-99m MAA, including perfusion SPECT, were compared with single-breath MRV with hyperpolarized He-3. RESULTS: Ventilation and perfusion defects correspond to areas of poor ventilation on MRV. High-resolution MRV images show preservation of bronchi and acinus units in areas of the "stripe sign" on the V/Q study. CONCLUSIONS: MRV imaging confirms that the stripe sign seen on nuclear perfusion imaging correlates with subsegmental preserved lung. MRV imaging has the potential for high-resolution innovative studies of subsegmental lung function, using either He-3 or Xe-129 hyperpolarized gases.

  11. Quantification of lung injury using ventilation and perfusion distributions obtained from gamma scintigraphy.

    PubMed

    Brook, B S; Murphy, C M; Breen, D; Miles, A W; Tilley, D G; Wilson, A J

    2007-12-01

    This paper explores the potential of isotope V/Q lung scans to quantify lung disease. Areas of restricted perfusion in subjects with a pulmonary embolus (PE) were identified in 3D reconstructions of V/Q images achieved using anatomical data from the Visible Human Project. From these, the extent of lung damage was quantified. Significant differences in the values of both LogSD V and LogSD Q (p > 0.05) obtained from plots of V and Q against Log(V/Q) were found between normal subjects and subjects with a PE, but no correlation was found between either of these parameters and the degree of lung damage in subjects with a PE (p > 0.05). Whilst V/Q values were log normally distributed, the V/Q distributions from the subjects with a PE failed to show the bimodal distribution predicted from theoretical considerations and MIGET measurements previously reported. There was a statistically significant difference in the mean and standard deviation values of the V/Q distributions between normal subject and subjects with a PE (p < 0.05) but not in the median values (p > 0.05). There was no correlation between the mean, median and standard deviation of the distributions from the subjects with a PE and the percentage of damage present (p > 0.05).

  12. First Danish experience with ex vivo lung perfusion of donor lungs before transplantation.

    PubMed

    Henriksen, Ian Sune Iversen; Møller-Sørensen, Hasse; Møller, Christian Holdfold; Zemtsovski, Mikhail; Nilsson, Jens Christian; Seidelin, Casper Tobias; Perch, Michael; Iversen, Martin; Steinbrüchel, Daniel

    2014-03-01

    The number of lung transplantations is limited by a general lack of donor organs. Ex vivo lung perfusion (EVLP) is a novel method to optimise and evaluate marginal donor lungs prior to transplantation. We describe our experiences with EVLP in Denmark during the first year after its introduction. The study was conducted by prospective registration of donor offers and lung transplantations in Denmark from 1 May 2012 to 30 April 2013. Donor lungs without any contraindications were transplanted in the traditional manner. Taken for EVLP were donor lungs that were otherwise considered transplantable, but failed to meet the usual criteria due to possible contusions or because they were from donors with sepsis or unable to pass the oxygenation test. In the study period, seven of 33 Danish lung transplantations were made possible due to EVLP. One patient died of non-EVLP-related causes, but all other recipients were alive with normal graft function at the end of our registration period. All lungs showed an improved PaO2/FiO2 ratio from a median 23.1 kPa (8.8-38.9) within the donor to 58.8 kPa (34.9-76.5) (FiO2 = 1.0) after EVLP, which corresponds to a 155% improved oxygenation. The median time to extubation, time in intensive care unit and the admission period were 1, 7 and 39 days, respectively. In the first year after the introduction of EVLP in Denmark, seven pairs of donor lungs that previously would have been rejected have been transplanted as a result of their improved function. EVLP seems to be a safe way to increase the use of marginal donor lungs. no funding was granted for the present paper. not relevant.

  13. Doppler flow evaluation can anticipate abnormal left lung perfusion after transcatheter closure of patent ductus arteriosus.

    PubMed

    Soares, Andressa M; Aiello, Vera D; Andrade, José L; Kajita, Luis J; Soares, José; Morhy, Samira S; Mathias, Wilson; Lopes, Antonio A B; Ramires, José A F

    2004-11-01

    Coil protrusion into the left pulmonary artery (LPA) has been described after transcatheter closure of the patent ductus arteriosus (PDA). The possible impact of such a finding in lung perfusion has not been completely clarified. We evaluated Doppler flow velocities and lung perfusion in patients submitted to that procedure. After transcatheter closure of PDA with coils, 70 patients (mean age 8.6+/-3.4 years) were followed for a period of 3.6+/-0.9 years (range 2.1-5.9) and compared to 22 controls. Peak flow velocities and coil protrusion were assessed by Doppler echocardiography. A Doppler velocity index (DVI) was calculated by the difference between the LPA and right pulmonary artery (RPA) peak flow velocities relative to the pulmonary trunk (PT) expressed in percentage, as follows: DVI=(LPA velocity - RPA velocity)/PT velocity x 100. Lung scintigraphy was performed using (99m)Tc-labelled macro-aggregated albumin. Device protrusion was observed in 94% of the patients, 10% of whom presented abnormal left lung perfusion. Peak LPA velocity and DVI were significantly greater in patients (p=0.001) and correlated negatively with left lung perfusion values (R(2)=0.21 and R(2)=0.65, respectively). A cut-off value of 50% for the DVI showed high sensitivity and specificity for reduced lung perfusion. Impaired left lung perfusion may appear following transcatheter closure of PDA with coils and the determination of DVI may anticipate such alteration.

  14. Propofol attenuates oxidant-induced acute lung injury in an isolated perfused rabbit-lung model.

    PubMed

    Yumoto, Masato; Nishida, Osamu; Nakamura, Fujio; Katsuya, Hirotada

    2005-01-01

    Reactive oxygen species have been strongly implicated in the pathogenesis of acute lung injury (ALI). Some animal studies suggest that free radical scavengers inhibit the onset of oxidant-induced ALI. Propofol (2,6-diisopropylphenol) is chemically similar to phenol-based free radical scavengers such as the endogenous antioxidant vitamin E. Both in vivo and in vitro studies have suggested that propofol has antioxidant potential. We hypothesized that propofol may attenuate ALI by acting as a free-radical scavenger. We investigated the effects of propofol on oxidant-induced ALI induced by purine and xanthine oxidase (XO), in isolated perfused rabbit lung, in two series of experiments. In series 1, we examined the relationship between the severity of ALI and the presence of hydrogen peroxide (H2O2). In series 2, we evaluated the effects of propofol on attenuating ALI and the dose dependence of these effects. The lungs were perfused for 90 min, and we evaluated the effects on the severity of ALI by monitoring the pulmonary capillary filtration coefficient (Kfc), pulmonary arterial pressure (Ppa), and the pulmonary capillary hydrostatic pressure (Ppc). In series 1, treatment with catalase (an H2O2 scavenger) prior to the addition of purine and XO resulted in complete prevention of ALI, suggesting that H2O2 may be involved closely in the pathogenesis of ALI. In series 2, pretreatment with propofol at concentrations in excess of 0.5 mM significantly inhibited the increases in the Kfc values, and that in excess of 0.75 mM significantly inhibited the increase in the Ppa values. Propofol attenuates oxidant-induced ALI in an isolated perfused rabbit lung model, probably due to its antioxidant action.

  15. 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.

  16. Identification of pulmonary emboli in the dog: comparison of angioscopy and perfusion scanning

    SciTech Connect

    Shure, D.; Moser, K.M.; Harrell, J.H.; Hartman, M.T.

    1981-09-01

    Fifteen dogs were studied by perfusion scan, angioscopy and autopsy. In 10, emboli were formed in leg veins and released before study; five dogs were not embolized and served as controls. In controls, angioscopy disclosed no emboli, perfusion scans were normal after angioscopy and autopsy disclosed no emboli. Among the embolized dogs, 23 emboli were identified at autopsy. Perfusion scans disclosed 23 defects, but in three dogs there was a disparity between scan and autopsy localization. Angioscopy identified 21 of the 23 autopsy-defined emboli and localized them correctly; two emboli in vessels less than 1 mm in diameter were not visualized. Angioscopy may provide a useful new approach in animal investigations of pulmonary embolism and perhaps, after additional study, in selected patients.

  17. Usefulness of dipyridamole-thallium-201 perfusion scanning for distinguishing ischemic from nonischemic cardiomyopathy

    SciTech Connect

    Eichhorn, E.J.; Kosinski, E.J.; Lewis, S.M.; Hill, T.C.; Emond, L.H.; Leland, O.S.

    1988-11-01

    To determine noninvasively the etiology of left ventricular (LV) dysfunction, 22 patients with a diagnosis of cardiomyopathy determined via cardiac catheterization and 5 normal control subjects underwent radionuclide ventriculography and intravenous dipyridamole-thallium-201 perfusion scanning. Both ischemically and nonischemically induced LV dysfunction had comparable global LV ejection fractions (24 +/- 6 vs 23 +/- 8%, respectively) and extent of segmental wall motion abnormalities. Right ventricular ejection fraction was significantly better in the group with an ischemic etiology of LV dysfunction (41 +/- 26 vs 13 +/- 10%, p less than 0.005) but significant group overlap was present. However, computer-assisted analysis of dipyridamole-thallium-201 myocardial perfusion scanning demonstrated more homogeneous myocardial perfusion in idiopathic cardiomyopathy (mean perfusion defect 25 +/- 11 vs 6 +/- 6%, p less than 0.001) and successfully predicted the correct etiology of LV dysfunction in 20 of 22 (91%) patients.

  18. Betamethasone treatment and fetal lung perfusion evaluated with color Doppler energy imaging.

    PubMed

    Dubiel, M; Gudmundsson, S; Pirhonen, J; Breborowicz, G H; Marsal, K

    1997-10-01

    The aim of this study was semiquantitative evaluation of tissue blood flow in the fetal lung before and after administration of betamethasone. This was carried out by means of computer analysis of ultrasound Doppler signals obtained by the color Doppler energy (CDE) technique. CDE signals were recorded in 20 singleton pregnancies with appropriate growth and imminent preterm delivery between 26 and 33 weeks of gestation. The CDE signal recordings were made before and after intramuscular administration of betamethasone 8 mg/day for 3 days. Fixed preset CDE system control settings for the fetal right lung were used during the examinations. Images from CDE scans were recorded on S-VHS videotape and transmitted for computer analysis of 8-bit images at 256 gray-scale levels. The mean flow signal intensity was recorded for the fetal lung before and after betamethasone administration. Additionally, blood velocity waveforms were measured in the intrapulmonary arteries and veins in the peripheral part of the lung. CDE signals from the fetal lung indicated increased energy values after corticosteroid treatment in 16 cases. In three cases there was no change in CDE signal values, and in one case a fall of the signal value was noted. Blood velocity waveforms from the intrapulmonary arteries showed decreased resistance to flow in 15 cases, increased resistance to flow in four cases and no change in one case. No significant differences in venous blood flow velocities were found. In conclusion, the results suggest that there is an increase in fetal lung blood perfusion after maternal corticosteroid administration.

  19. Indium 111 autologous leucocyte scanning in lobar pneumonia and lung abscesses.

    PubMed Central

    Saverymuttu, S H; Phillips, G; Peters, A M; Lavender, J P

    1985-01-01

    Indium 111 leucocyte scanning was used to examine the kinetics of granulocyte localisation in five patients with lobar pneumonia and four patients with lung abscess. Lung abscesses showed dense accumulation of labelled granulocytes within four hours of injection. In contrast, in all cases of lobar pneumonia granulocytes failed to accumulate over a period of up to 24 hours despite evidence of adequate perfusion and of uptake in inflammation elsewhere. These results suggest that the recruitment of granulocytes to lobar pneumonia may be terminated early in its clinical course. Images PMID:4095674

  20. Altered Immunogenicity of Donor Lungs via Removal of Passenger Leukocytes Using Ex Vivo Lung Perfusion.

    PubMed

    Stone, J P; Critchley, W R; Major, T; Rajan, G; Risnes, I; Scott, H; Liao, Q; Wohlfart, B; Sjöberg, T; Yonan, N; Steen, S; Fildes, J E

    2016-01-01

    Passenger leukocyte transfer from the donor lung to the recipient is intrinsically involved in acute rejection. Direct presentation of alloantigen expressed on donor leukocytes is recognized by recipient T cells, promoting acute cellular rejection. We utilized ex vivo lung perfusion (EVLP) to study passenger leukocyte migration from donor lungs into the recipient and to evaluate the effects of donor leukocyte depletion prior to transplantation. For this purpose, female pigs received male left lungs either following 3 h of EVLP or retrieved using standard protocols. Recipients were monitored for 24 h and sequential samples were collected. EVLP-reduced donor leukocyte transfer into the recipient and migration to recipient lymph nodes was markedly reduced. Recipient T cell infiltration of the donor lung was significantly diminished via EVLP. Donor leukocyte removal during EVLP reduces direct allorecognition and T cell priming, diminishing recipient T cell infiltration, the hallmark of acute rejection. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

  1. (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. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Surface Fluorescence Studies of Tissue Mitochondrial Redox State in Isolated Perfused Rat Lungs

    PubMed Central

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

    2012-01-01

    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 of 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’s health in real-time. PMID:23238793

  3. A Leukocyte Filter Does Not Provide Further Benefit During Ex Vivo Lung Perfusion.

    PubMed

    Luc, Jessica G Y; Aboelnazar, Nader S; Himmat, Sayed; Hatami, Sanaz; Haromy, Alois; Matsumura, Nobutoshi; Vasanthan, Vishnu; White, Christopher W; Mengel, Michael; Freed, Darren H; Nagendran, Jayan

    2017-02-20

    Normothermic ex vivo lung perfusion (EVLP) allows for assessment and reconditioning of donor lungs. Though a leukocyte filter (LF) is routinely incorporated into the EVLP circuit, its efficacy remains to be determined. Twelve pig lungs were perfused and ventilated ex vivo in a normothermic state for 12 hours. Lungs (n=3) were allocated to 4 groups according to perfusate composition and the presence or absence of a LF in the circuit (acellular ± LF, cellular ± LF). Acceptable physiologic lung parameters were achieved during EVLP; however, increased amounts of pro-inflammatory cytokines (TNF-α, IL-6) and leukocytes in the perfusate were observed despite the presence or absence of a LF. Analysis of cells washed off the LF demonstrates that it trapped leukocytes though was ineffective throughout perfusion as it became saturated over 12 hours. We conclude that there is no objective evidence to support the routine incorporation of a LF during EVLP as it does not provide further benefit and its removal does not appear to cause harm. The lack of hypothesized benefit to a LF may be due to the saturation of the LF with donor leukocytes, leading to similar amounts of circulating leukocytes still present in the perfusate with and without a LF.

  4. Comparison of scanning beam and whole field laser Doppler perfusion imaging

    NASA Astrophysics Data System (ADS)

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

    2010-02-01

    Currently, laser perfusion imaging (LDPI) is undergoing a technology shift from scanning beam perfusion imagers to whole field systems. The latter can be subdivided in laser Doppler methods systems based on high speed CMOS cameras, and laser speckle contrast analysis (LASCA) technologies using slow imaging arrays, mostly CCD-based. In scanning beam systems, a collimated laser beam scans the tissue with diffusely back reflected light being captured with a single detector. In whole field systems a large tissue area is illuminated, and the reflected light is imaged onto an array and captured at once. Unlike scanning beam systems, both whole field methods enable perfusion imaging at video rate. In this study we experimentally compare the scanning beam LDPI principle with whole field LDPI, using Intralipid phantoms. For the tissue phantoms, the Monte Carlo simulation technique will be used as a reference. From measurements on Intralipid phantoms compared to Monte Carlo, we conclude that in whole field LDPI the flux image, representing the first order moment of the power spectrum of photocurrent fluctuations is much closer related to real perfusion than for scanning beam systems. This difference can be explained in terms of the different behaviour of dynamic speckle patterns generated in both methods, in response to varying tissue optical properties.

  5. Clinical Outcome of Patients Transplanted with Marginal Donor Lungs via Ex Vivo Lung Perfusion Compared to Standard Lung Transplantation.

    PubMed

    Fildes, James E; Archer, Louise D; Blaikley, John; Ball, Alexandra L; Stone, John P; Sjöberg, Trygve; Steen, Stig; Yonan, Nizar

    2015-05-01

    Lung transplantation is limited by a scarcity of suitable donors resulting in high waiting list mortality. Ex vivo lung perfusion (EVLP) allows the evaluation and reconditioning of marginal donor lungs for use in transplantation. This study aimed to compare clinical outcome of patients transplanted with marginal organs by means of EVLP with a standard lung transplant cohort through a multicenter open trial. Group 1 (n = 9) included patients transplanted using EVLP reconditioned marginal lungs. Group 2 (n = 46) consisted of date-matched patients transplanted using standard transplantation of acceptable lungs. The primary composite endpoint included acute rejection and infection at 12 months after transplantation. There was no significant difference in the overall incidence of acute rejection (P = 0.754) and the number of treated infection episodes (proven/probable pneumonia; P = 0.857/0.368 and proven/probable tracheobronchitis; P = 0.226/0.529) up to 12 months after transplantation, between group 1 and group 2. Additionally, there was no significant difference in early clinical outcome, including intensive care unit stay, hospital stay, and 1 year mortality between the two groups (P = 0.338, P = 0.112 and P = 0.372, respectively). This multicenter study demonstrates that EVLP is associated with no adverse effect on clinical outcome, including the incidence of acute rejection and infection after lung transplantation.

  6. Value of the ventilation/perfusion scan in acute pulmonary embolism. Results of the prospective investigation of pulmonary embolism diagnosis (PIOPED).

    PubMed

    To determine the sensitivities and specificities of ventilation/perfusion lung scans for acute pulmonary embolism, a random sample of 933 of 1493 patients was studied prospectively. Nine hundred thirty-one underwent scintigraphy and 755 underwent pulmonary angiography; 251 (33%) of 755 demonstrated pulmonary embolism. Almost all patients with pulmonary embolism had abnormal scans of high, intermediate, or low probability, but so did most without pulmonary embolism (sensitivity, 98%; specificity, 10%). Of 116 patients with high-probability scans and definitive angiograms, 102 (88%) had pulmonary embolism, but only a minority with pulmonary embolism had high-probability scans (sensitivity, 41%; specificity, 97%). Of 322 with intermediate-probability scans and definitive angiograms, 105 (33%) had pulmonary embolism. Follow-up and angiography together suggest pulmonary embolism occurred among 12% of patients with low-probability scans. Clinical assessment combined with the ventilation/perfusion scan established the diagnosis or exclusion of pulmonary embolism only for a minority of patients--those with clear and concordant clinical and ventilation/perfusion scan findings.

  7. 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.

  8. 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.

  9. An observational study of Donor Ex Vivo Lung Perfusion in UK lung transplantation: DEVELOP-UK.

    PubMed Central

    Fisher, Andrew; Andreasson, Anders; Chrysos, Alexandros; Lally, Joanne; Mamasoula, Chrysovalanto; Exley, Catherine; Wilkinson, Jennifer; Qian, Jessica; Watson, Gillian; Lewington, Oli; Chadwick, Thomas; McColl, Elaine; Pearce, Mark; Mann, Kay; McMeekin, Nicola; Vale, Luke; Tsui, Steven; Yonan, Nizar; Simon, Andre; Marczin, Nandor; Mascaro, Jorge; Dark, John

    2016-01-01

    BACKGROUND Many patients awaiting lung transplantation die before a donor organ becomes available. Ex vivo lung perfusion (EVLP) allows initially unusable donor lungs to be assessed and reconditioned for clinical use. OBJECTIVE The objective of the Donor Ex Vivo Lung Perfusion in UK lung transplantation study was to evaluate the clinical effectiveness and cost-effectiveness of EVLP in increasing UK lung transplant activity. DESIGN A multicentre, unblinded, non-randomised, non-inferiority observational study to compare transplant outcomes between EVLP-assessed and standard donor lungs. SETTING Multicentre study involving all five UK officially designated NHS adult lung transplant centres. PARTICIPANTS Patients aged ≥ 18 years with advanced lung disease accepted onto the lung transplant waiting list. INTERVENTION The study intervention was EVLP assessment of donor lungs before determining suitability for transplantation. MAIN OUTCOME MEASURES The primary outcome measure was survival during the first 12 months following lung transplantation. Secondary outcome measures were patient-centred outcomes that are influenced by the effectiveness of lung transplantation and that contribute to the health-care costs. RESULTS Lungs from 53 donors unsuitable for standard transplant were assessed with EVLP, of which 18 (34%) were subsequently transplanted. A total of 184 participants received standard donor lungs. Owing to the early closure of the study, a non-inferiority analysis was not conducted. The Kaplan-Meier estimate of survival at 12 months was 0.67 [95% confidence interval (CI) 0.40 to 0.83] for the EVLP arm and 0.80 (95% CI 0.74 to 0.85) for the standard arm. The hazard ratio for overall 12-month survival in the EVLP arm relative to the standard arm was 1.96 (95% CI 0.83 to 4.67). Patients in the EVLP arm required ventilation for a longer period and stayed longer in an intensive therapy unit (ITU) than patients in the standard arm, but duration of overall hospital

  10. The evolving potential for pediatric ex vivo lung perfusion.

    PubMed

    Luc, Jessica G Y; Nagendran, Jayan

    2016-02-01

    Despite the rise in the number of adult lung transplantations performed, rates of pediatric lung transplantation remain low. Lung transplantation is an accepted therapy for pediatric end-stage lung disease; however, it is limited by a shortage of donor organs. EVLP has emerged as a platform for assessment and preservation of donor lung function. EVLP has been adopted in adult lung transplantation and has successfully led to increased adult lung transplantations and donor lung utilization. We discuss the future implications of EVLP utilization, specifically, its potential evolving role in overcoming donor shortages in smaller children and adolescents to improve the quality and outcomes of lung transplantation in pediatric patients.

  11. Ex vivo lung perfusion: a comprehensive review of the development and exploration of future trends.

    PubMed

    Roman, Marius A; Nair, Sukumaran; Tsui, Steven; Dunning, John; Parmar, Jasvir S

    2013-09-01

    There is a critical mismatch between the number of donor lungs available and the demand for lungs for transplantation. This has created unacceptably high waiting-list mortality for lung transplant recipients. Currently (2012) in the United Kingdom, there are 216 patients on the lung transplant waiting list and 17 on heart and lung transplant list. The waiting times for suitable lungs average 412 days, with an increasing mortality and morbidity among the patients on the lung transplant list. Ex vivo lung perfusion (EVLP) has emerged as a technique for the assessment, resuscitation, and potential repair of suboptimal donor lungs. This is a rapidly developing field with significant clinical implications. In this review article, we critically appraise the background developments that have led to our current clinical practice. In particular, we focus on the human and animal experience, the different perfusion-ventilation strategies, and the impact of different perfusates and leukocyte filters. Finally, we examine EVLP as a potential research tool. This will provide insight into EVLP and its future development in the field of clinical lung transplantation.

  12. Automated lung segmentation of low resolution CT scans of rats

    NASA Astrophysics Data System (ADS)

    Rizzo, Benjamin M.; Haworth, Steven T.; Clough, Anne V.

    2014-03-01

    Dual modality micro-CT and SPECT imaging can play an important role in preclinical studies designed to investigate mechanisms, progression, and therapies for acute lung injury in rats. SPECT imaging involves examining the uptake of radiopharmaceuticals within the lung, with the hypothesis that uptake is sensitive to the health or disease status of the lung tissue. Methods of quantifying lung uptake and comparison of right and left lung uptake generally begin with identifying and segmenting the lung region within the 3D reconstructed SPECT volume. However, identification of the lung boundaries and the fissure between the left and right lung is not always possible from the SPECT images directly since the radiopharmaceutical may be taken up by other surrounding tissues. Thus, our SPECT protocol begins with a fast CT scan, the lung boundaries are identified from the CT volume, and the CT region is coregistered with the SPECT volume to obtain the SPECT lung region. Segmenting rat lungs within the CT volume is particularly challenging due to the relatively low resolution of the images and the rat's unique anatomy. Thus, we have developed an automated segmentation algorithm for low resolution micro-CT scans that utilizes depth maps to detect fissures on the surface of the lung volume. The fissure's surface location is in turn used to interpolate the fissure throughout the lung volume. Results indicate that the segmentation method results in left and right lung regions consistent with rat lung anatomy.

  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. Markers of left ventricular dysfunction induced by exercise, dipyridamole or combined stress on ECG-gated myocardial perfusion scans.

    PubMed

    Hurwitz, G A; O'Donoghue, J P; MacDonald, A C; Laurin, N R; Powe, J E

    1993-04-01

    An index of left ventricular contraction can be extracted from the cavitary time-activity curve of electrocardiographic (ECG)-gated myocardial perfusion scans. To assess the induction of stress-induced myocardial depression, we compared contraction indexes derived from immediate poststress and delayed 201Tl images with indexes of ventricular dilation and lung uptake in the prediction of severe coronary artery disease (defined as two or more 90% stenoses). Stress procedures were performed in 93 patients with symptom-limited supine bicycle exercise alone, and in 227 with intravenous dipyridamole, combined where possible with exercise. The immediate and delayed contraction indexes reflected left ventricular dysfunction on ventriculography (P < 0.0001), but additionally the immediate index was reduced (P < 0.0001) in severe coronary disease. Stress-induced hypokinesis was seen frequently after each of the test modes. The relationship with angiographic findings was better defined for indexes of contraction than for lung uptake or ventricular dilation (P < 0.01). The prediction of severe coronary disease was optimized by combining the poststress contraction index and lung uptake. These data support the use of ECG-gated myocardial scans in evaluating the functional consequences of stress/imaging procedures.

  16. 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.

  17. Differential role of actin in lung endothelial and epithelial barrier properties in perfused rabbit lungs.

    PubMed

    Ermert, L; Rössig, R; Hansen, T; Schütte, H; Aktories, K; Seeger, W

    1996-01-01

    Lung fluid balance is critically dependent on capillary endothelial and alveolar epithelial barrier properties, and cytoskeletal components have been implicated in these barrier functions. In an earlier study, we perfused Clostridium botulinum C2 toxin, which effects selective loss of non-muscle F-actin, through isolated rabbit lungs: a severalfold increase in the capillary filtration coefficient (Kfc) was noted, together with attenuations and disruptions of endothelial cells upon electron microscopic examination. In this model we have investigated the influence of the C2 toxin on alveolar epithelial barrier properties. Epithelial permeability was assessed by continuous monitoring of the transepithelial passage of technetium-labelled diethylenetriamine penta-acetic acid (99mTc-DTPA), offered to the alveolar surface by aerosol technique. Intravascular administration of hydrogen peroxide, used as control agent, was shown to provoke a four- to fivefold increase in the clearance rate of 99mTc-DTPA under conditions of severe fluid leakage into the lung interstitial and alveolar space. Intravascular administration of C2 toxin caused a dose- and time-dependent increase in Kfc values (8-15 fold), but the Tc-DTPA clearance rate was entirely unaffected. Moreover, transbronchial application of C2 toxin again reproduced the manifold increase in Kfc data (about six fold), but the rate of transepithelial passage of the hydrophilic Tc-DTPA complex remained unchanged. We conclude that the barrier properties of the lung microvascular endothelial and epithelial layer are differentially regulated. It is suggested that the actin microfilament system plays a decisive role in the structural and functional integrity of the endothelial but not the epithelial barrier.

  18. Evaluation of postoperative lung volume and perfusion changes by dual-energy computed tomography in patients with lung cancer.

    PubMed

    Choe, Jooae; Lee, Sang Min; Chae, Eun Jin; Lee, Sang Min; Kim, Yong-Hee; Kim, Namkug; Seo, Joon Beom

    2017-05-01

    The aim of our study was to retrospectively evaluate postoperative physiologic changes in lung cancer patients using dual-energy CT (DECT), and develop modified methods reflecting postoperative change for predicting pulmonary function. 88 patients (M:F=64:24; mean age, 63.5 years) with lung cancer who underwent DECT and pulmonary function tests before and after operation were included. Volume and iodine values for perfusion of each lobe were quantified. The predicted postoperative FEV1 using the current method was calculated by multiplying the preoperative FEV1 by the fractional contribution of perfusion of the remaining lung. The modified method reflecting postoperative volume change was compared to the current method. Postoperative lung volume showed compensatory increases in the contralateral and remaining ipsilateral lobes, with a significantly greater increase in the ipsilateral lobe than contralateral lobe (21.8%±46.2% vs. 10.0%±20.8%, P=0.031). Perfusion analysis showed blood volume increases in both ipsilateral and contralateral lobes without statistical differences (blood volume ratio difference, 29.2%±26.7 vs. 24.6%±16.5, P=0.368). The performance of the modified method considering postoperative lung volume change was comparable to that of the current method in the development and validation datasets (95% CI, -24.5% to 37.1% vs. -33.3% to 22.2% and -23.6% to 32.0% vs. -31.9% to 16.0%, respectively). Postoperative compensatory increases in lung volume and perfusion occur in different ways. Our modified method incorporating postoperative lung volume changes can be considered a comparable method for prediction of postoperative lung function. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. The natural history of venous thromboembolism: impact on ventilation/perfusion scan reporting.

    PubMed

    Gray, Henry W

    2002-07-01

    Deep vein thrombosis (DVT) and pulmonary embolism (PE) are separate but related aspects of the same dynamic disease process known as venous thromboembolism (VTE). Recent community studies have shown that VTE is a major health issue for the developed world, with at least 201,000 new cases each year in the United States, comprising 107,000 with DVT and 94,000 with PE. A quarter of PE cases die within 7 days, some so rapidly that treatment or intervention is impossible. Despite the availability of heparin prophylaxis, the annual incidence of VTE has remained constant at 1 event per 1,000 person-years since 1979 but reaches 1 event per 100 person-years for the over-85-year-olds. The most important risk factors for VTE are hemostatic and environmental. The recent discoveries of factor V Leiden, prothrombin 20210A, and high concentrations of factor VIII have highlighted the increasing importance of a genetic predisposition to thrombophilia. Acquired hemostatic factors include pregnancy and the puerperium, oral contraception, hormone-replacement therapy, malignant tumors, and antiphospholipid syndromes. Important environmental risk factors include hospitalization with previous surgery or trauma, confinement in a care facility, neurologic disease or paraplegia after stroke, current or recent central venous catheter or transvenous pacemaker, and long airplane flights. Internists may be confused about the risk of PE after ventilation/perfusion (VQ) imaging. This may well arise from their use of the relative risk of PE after a low-probability category scan rather than the absolute risk obtained by incorporating the PE prevalence for their particular patient in the risk analysis. Ideally, personal communication with an experienced referring physician provides this clinical information for nuclear medicine. Diagnostic tools or checklists can be used as an alternative. A general knowledge of the natural history of VTE will encourage the nuclear medicine physician to provide an

  20. 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.

  1. Natural course of treated pulmonary embolism. Evaluation by perfusion lung scintigraphy, gas exchange, and chest roentgenogram.

    PubMed

    Prediletto, R; Paoletti, P; Fornai, E; Perissinotto, A; Petruzzelli, S; Formichi, B; Ruschi, S; Palla, A; Giannella-Neto, A; Giuntini, C

    1990-03-01

    Perfusion lung scintigrams, pulmonary gas exchange data, and chest roentgenograms were obtained in 33 patients during acute embolism and over the following six months in order to assess their clinical usefulness in monitoring the effect of therapy. To this purpose, the measurement of pulmonary gas exchange and the presence of chest x-ray findings were compared with perfusion lung scintigraphic abnormalities both at diagnosis and after 7, 30, and 180 days during treatment. More than 50 percent of the pulmonary arterial tree was obstructed at diagnosis, and a large part of perfusion recovery was complete within the first month. All of the gas exchange parameters were abnormal at diagnosis, and the rate of their improvement was related to that of perfusion recovery. Interestingly, PaO2st (ie, PaO2 corrected for hyperventilation) and VE tended to return to normal during the first month as a consequence of the progressive recovery of perfusion, whereas oxygen and carbon dioxide gradients and physiologic dead space showed the persistence of some abnormalities six months after diagnosis. Significant correlations were observed between the number of ULSs evaluated on the perfusion lung scintigram (and considered an index of the severity of pulmonary embolization) and all of the gas exchange parameters at diagnosis (correlation coefficients averaged from 0.41 to 0.73) and after 7 and 30 days. The enlargement of the right descending pulmonary artery and particularly the "sausage" sign and the Westermark sign were significantly associated with a higher degree of gas exchange impairment and with a more severe embolization. In conclusion, this study demonstrates that perfusion lung scintigraphy has a primary role in monitoring the recovery of patients with pulmonary embolism under treatment. Moreover, the chest roentgenogram may help in this purpose. A second major result is that the simple measurement of some gas exchange parameters may allow the assessment of functional

  2. Comparison of Celsior and Perfadex lung preservation solutions in rat lungs subjected to 6 and 12 hours of ischemia using an ex-vivo lung perfusion system.

    PubMed

    Menezes, Arteiro Queiroz; Pêgo-Fernandes, Paulo Manuel; Cardoso, Paulo Francisco Guerreiro; Braga, Karina Andrighetti de Oliveira; Nepomuceno, Natalia Aparecida; Pazetti, Rogerio; Correia, Aristides Tadeu; Canzian, Mauro; Santim, Jacqueline Klarosk; Jatene, Fabio Biscegli

    2012-11-01

    This study evaluated the performance of lungs that were preserved with different solutions (Celsior, Perfadex or saline) in an ex vivo rat lung perfusion system. Sixty Wistar rats were anesthetized, anticoagulated and randomized into three groups (n = 20). The rats were subjected to antegrade perfusion via the pulmonary artery with Perfadex, Celsior, or saline, followed by 6 or 12 hours of ischemia (4ºC, n = 10 in each group). Respiratory mechanics, gas exchange and hemodynamics were measured at 10-minute intervals during the reperfusion of heart-lung blocks in an ex vivo system (IL2-Isolated Perfused Rat or Guinea Pig Lung System, Harvard Apparatus, Holliston, Massachusetts, USA; Hugo Sachs Elektronik, Germany) for 60 minutes. The lungs were prepared for histopathology and evaluated for edema following reperfusion. Group comparisons were performed using ANOVA and the Kruskal-Wallis test with a 5% level of significance. Gas exchange was not significantly different between lungs perfused with either Perfadex or Celsior at the same ischemic times, but it was very low in lungs that were preserved with saline. Airway resistance was greater in the lungs that were preserved for 12 hours. Celsior lungs that were preserved for 6 and 12 hours exhibited lower airway resistance (p = 0.01) compared to Perfadex lungs. Pulmonary artery pressure was not different between the groups, and no significant differences in histopathology and apoptosis were observed between the groups. Lungs that were preserved with Celsior or Perfadex exhibited similar gas exchange and histopathological findings. Airway resistance was slightly lower in the Celsior-preserved lungs compared with the Perfadex-preserved lungs.

  3. 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.

  4. Effect of Fenoterol on PAF-induced lung edema in isolated and perfused rabbit lungs.

    PubMed

    Pesce, L; Tristano, S; Friedman, E; Comellas, A; Marcano, H; Sanchez de León, R

    1998-11-01

    We have studied the effects of fenoterol on PAF-induced response in pulmonary circulation. We used 28 isolated and perfused rabbit lungs preparations: eight control preparations (CP), four vehicles preparations (VP), eight PAF preparations (PP) with two doses of PAF, one called low dose (LD = 0.5 microg/kg of weight) and the other high dose (HD = 1 microg/kg of weight) and eight Fenoterol preparations (FP) which we administered 0.05 mg of Fenoterol for 15 min, followed by a LD and HD of PAF. FP prevented elevation of pulmonary artery pressure (Ppa) as compared to PP, at LD of PAF: 12.615 (CI 95%: 8.57-20.885) versus 83.705 (CI 95%: 50.55-114.3) cm of water; and at HD of PAF: 19.38 (CI 95%: 11.235-28.94) versus 205.1 (CI 95%: 141.3-271) cm of water respectively. FP prevented the increase in fluid filtration rate (FFR) observed in PP at both doses of PAF LD: 0.765 (CI 95%: 0.07-3.385) versus 0.01 (CI 95%: -0.05-0.005) g/min; HD: 5.515 (CI 95%: 2.425-8.865) versus 0.03 (CI 95%: 0-0.33) g/min. Our results suggest that PAF has a vasoconstrictor effect that produces lung edema and this effect is inhibited by fenoterol.

  5. Clinical application of dual-source CT in the evaluation of patients with lung cancer: correlation with perfusion scintigraphy and pulmonary function tests.

    PubMed

    Fraioli, F; Serra, G; Liberali, S; Fiorelli, A; Liparulo, V; Zaccagna, F; Ciccariello, G; Catalano, C; Passariello, R

    2011-09-01

    This study was done to assess the diagnostic potential of dual-source computed tomography (DSCT) in the functional evaluation of lung cancer patients undergoing surgical resection. The CT data were compared with pulmonary perfusion scintigraphy and pulmonary function tests (PFTs). All patients were evaluated with DSCT, scintigraphy and PFTs. The DSCT scan protocol was as follows: two tubes (80 and 140 kV; Care Dose protocol); 70 cc of contrast material (5 cc/s); 5- to 6-s scan time; 0.6 mm collimation. After the automatic calculation of lung perfusion with DSCT and quantification of air volumes and emphysema with dedicated software applications, the perfusional CT studies were compared with scintigraphy using a visual score for perfusion defects; CT air volumes and emphysema were compared with PFTs. The values of accuracy, sensitivity, specificity and positive (PPV) and negative (NPV) predictive values of DSCT compared with perfusion scintigraphy as the reference standard were: 0.88, 0.84, 0.90, 0.93 and 0.88, respectively. The McNemar test did not identify significant differences either between the two imaging techniques (p=0.07) or between CT and PFTs (p=0.09). DSCT is a robust and promising technique that provides important and accurate information on lung function.

  6. 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.

  7. 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

  8. Lung ventilation- and perfusion-weighted Fourier decomposition magnetic resonance imaging: in vivo validation with hyperpolarized 3He and dynamic contrast-enhanced MRI.

    PubMed

    Bauman, Grzegorz; Scholz, Alexander; Rivoire, Julien; Terekhov, Maxim; Friedrich, Janet; de Oliveira, Andre; Semmler, Wolfhard; Schreiber, Laura Maria; Puderbach, Michael

    2013-01-01

    The purpose of this work was to validate ventilation-weighted (VW) and perfusion-weighted (QW) Fourier decomposition (FD) magnetic resonance imaging (MRI) with hyperpolarized (3)He MRI and dynamic contrast-enhanced perfusion (DCE) MRI in a controlled animal experiment. Three healthy pigs were studied on 1.5-T MR scanner. For FD MRI, the VW and QW images were obtained by postprocessing of time-resolved lung image sets. DCE acquisitions were performed immediately after contrast agent injection. (3)He MRI data were acquired following the administration of hyperpolarized helium and nitrogen mixture. After baseline MR scans, pulmonary embolism was artificially produced. FD MRI and DCE MRI perfusion measurements were repeated. Subsequently, atelectasis and air trapping were induced, which followed with FD MRI and (3)He MRI ventilation measurements. Distributions of signal intensities in healthy and pathologic lung tissue were compared by statistical analysis. Images acquired using FD, (3)He, and DCE MRI in all animals before the interventional procedure showed homogeneous ventilation and perfusion. Functional defects were detected by all MRI techniques at identical anatomical locations. Signal intensity in VW and QW images was significantly lower in pathological than in healthy lung parenchyma. The study has shown usefulness of FD MRI as an alternative, noninvasive, and easily implementable technique for the assessment of acute changes in lung function. Copyright © 2012 Wiley Periodicals, Inc.

  9. 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…

  10. 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…

  11. Accuracy and feasibility of dynamic contrast-enhanced 3D MR imaging in the assessment of lung perfusion: comparison with Tc-99 MAA perfusion scintigraphy.

    PubMed

    Yilmaz, E; Akkoclu, A; Degirmenci, B; Cooper, R A; Sengun, B; Gulcu, A; Osma, E; Ucan, E S

    2005-08-01

    The aim of this study was to correlate findings of perfusion magnetic resonance imaging (MRI) and perfusion scintigraphy in cases where there was a suspicion of abnormal pulmonary vasculature, and to evaluate the usefulness of MRI in the detection of perfusion deficits of the lung. In all, 17 patients with suspected abnormality of the pulmonary vasculature underwent dynamic contrast-enhanced MRI. T1-weighted 3D fast-field echo pulse sequences were obtained (TR/TE 3.3/1.58 ms; flip angle 30 degrees; slice thickness 12 to 15 mm). The dynamic study was acquired in the coronal plane following administration of 0.1 mmol/kg gadopentetate dimeglumine. A total of 8 to 10 sections repeated 20 to 25 times at intervals of 1s were performed. Perfusion lung scintigraphy was carried out a maximum of 48 h before the MR examination in all cases. Two radiologists, who were blinded to the clinical data and results of other imaging methods, reviewed all coronal sections. MR perfusion images were independently assessed in terms of segmental or lobar perfusion defects in the 85 lobes of the 17 individuals, and the findings were compared with the results of scintigraphy. Of the 17 patients, 8 were found to have pulmonary emboli, 2 chronic obstructive pulmonary disease with emphysema, 2 bullous emphysema, 2 Takayasu arteritis and 1 had a hypoplastic pulmonary artery. Pulmonary perfusion was completely normal in 2 cases. In 35 lobes, perfusion defects were detected using both methods, in 4 with MR alone and in 9 only with scintigraphy. There was good agreement between MRI and scintigraphy findings (kappa=0.695). Pulmonary perfusion MRI is a new alternative to scintigraphy in the evaluation of pulmonary perfusion for various lung disorders. In addition, this technique allows measurement and quantification of pulmonary perfusion abnormalities.

  12. Repeat perfusion imaging may differentiate airways obstruction from pulomonary embolic disease: report of two cases

    SciTech Connect

    Greenspon, L.W.; LaManna, M.M.; Dhand, S.

    1987-06-01

    Two cases are presented in which patients with obstructive lung disease were considered to have a pulmonary embolism (PE). Emergency lung perfusion scans supported the diagnosis of PE in both cases. However, rapid resolution of the symptoms and perfusion defects by repeat ventilation-perfusion scanning at 24 hr suggested that PE was unlikely. In selected cases of wheezing patients, repeat perfusion scans may obviate the need for pulmonary angiography. The authors report two cases in which repeat perfusion scans almost normalized by 24 hr. Review of the literature indicates that the rate of resolution of perfusion defects would have been much slower had pulmonary embolism occurred.

  13. Advances in machine perfusion graft viability assessment in kidney, liver, pancreas, lung, and heart transplant.

    PubMed

    Balfoussia, Danai; Yerrakalva, Dharani; Hamaoui, Karim; Papalois, Vassilios

    2012-04-01

    Solid organ transplant constitutes the definitive treatment for end-stage organ failure. Better organ preservation methods have enabled use of marginal grafts, thereby expanding the donor pool to meet the growing demand for organs. Static cold storage as a preservation method has been superseded largely by machine perfusion in kidney transplant, with work regarding its use in other organ transplants ongoing. We hope that machine perfusion will allow better graft preservation, and pretransplant assessment, and optimization. The most extensive laboratory, preclinical, and clinical research into machine perfusion organ preservation has focused on kidneys. Successful outcomes in its use in renal transplant have sparked interest for its development and application to the liver, pancreas, heart, and lungs. This article reviews the current state of machine perfusion in abdominal and thoracic organ transplant, focusing on the recent developments in assessing graft viability.

  14. 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)

  15. Thromboxane release from irradiated perfused rat lungs: role of oncotic agents

    SciTech Connect

    Heinz, T.R.; Kot, P.A.; Ramwell, P.W.; Schneidkraut, M.J.

    1987-07-27

    Isolated lungs from 20 Gray (Gy) whole body irradiated rats were perfused with Krebs-Ringer bicarbonate plus 3% bovine serum albumin (KRB-BSA). The pulmonary effluent showed a 99% (p < .05) increase in immunoassayable thromboxane B2 (iTXB2) release compared with non-irradiated lungs. Since both arachidonic acid and cyclooxygenase products bind to albumin, studies were performed to determine if omission or substitution of this protein oncotic agent would alter the radiation-induced increase in pulmonary iTXB2 release. Irradiated, isolated lungs perfused with media from which the BSA was omitted (KRB) did not demonstrate the radiation-induced increase in pulmonary iTXB2 release. Similarly, irradiated lungs perfused with media in which Dextran 70 (KRB plus 3% Dextran 70, KRB-Dextran 70) was substituted for BSA also did not show the radiation-induced increase in pulmonary effluent iTXB2 levels. These studies demonstrate the importance of including albumin as the oncotic agent in perfused organ systems when studying cyclooxygenase product release. 23 references, 2 tables.

  16. 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)

  17. A physiologic and biochemical profile of clinically rejected lungs on a normothermic ex vivo lung perfusion platform.

    PubMed

    George, Timothy J; Arnaoutakis, George J; Beaty, Claude A; Jandu, Simran K; Santhanam, Lakshmi; Berkowitz, Dan E; Shah, Ashish S

    2013-07-01

    Although ex vivo lung perfusion (EVLP) is increasingly being used to evaluate and manipulate potential donor lungs before lung transplantation (LTx), data on the biochemistry of lungs during EVLP are limited. In this study, we examined the physiology and biochemistry of human lungs on an EVLP circuit. We recovered unallocated double lungs in standard fashion and split them into single lungs. All lungs received a nebulized arginase inhibitor, 2-S-amino-6-boronohexanoic acid (ABH), at either the onset (n = 6) or after 3 h (n = 8) of EVLP. Serial biochemical analysis included levels of arginase, endogenous nitric oxide synthase (eNOS), cyclic guanosine monophosphate, and reactive oxygen species. We considered lungs transplantable if they sustained a PaO2:FiO2 ≥ 350 in addition to stable pulmonary function during EVLP. We recovered a total of 14 single lungs. We deemed three single lungs from different donors to be transplantable after EVLP. These lungs had superior oxygenation, lower carbon dioxide, and more stable pulmonary artery pressures. Transplantable lungs had higher baseline levels of eNOS and higher final levels of cyclic guanosine monophosphate than non-transplantable lungs. Early ABH administration was associated with a transient increase in dynamic compliance. In this biochemical characterization of lungs deemed unsuitable for LTx, early levels of eNOS and late levels of cyclic guanosine monophosphate appear to be associated with improved allograft function during EVLP. In addition, nebulized ABH is associated with a significant increase in dynamic compliance. These data suggest that biochemical markers during EVLP may predict acceptable allograft function, and that this platform can be used to biochemically manipulate donor lungs before LTx. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Modeling of the lung nodules for detection in LDCT scans.

    PubMed

    Farag, Amal; Elhabian, Shireen; Graham, James; Farag, Aly; Elshazly, Salwa; Falk, Robert; Mahdi, Hani; Abdelmunim, Hossam; Al-Ghaafary, Sahar

    2010-01-01

    A novel approach is proposed for generating data driven models of the lung nodules appearing in low dose CT (LDCT) scans of the human chest. Four types of common lung nodules are analyzed using Active Appearance Model methods to create descriptive lung nodule models. The proposed approach is also applicable for automatic classification of nodules into pathologies given a descriptive database. This approach is a major step forward for early diagnosis of lung cancer. We show the performance of the new nodule models on clinical datasets which illustrates significant improvements in both sensitivity and specificity.

  19. 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

  20. Quantifying Single Microvessel Permeability in Isolated Blood-perfused Rat Lung Preparation

    PubMed Central

    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. PMID:25045895

  1. Significance of single ventilation/perfusion mismatches in krypton-81m/technetium-99m lung scintigraphy

    SciTech Connect

    Rosen, J.M.; Palestro, C.J.; Markowitz, D.; Alderson, P.O.

    1986-03-01

    The significance of a single area of ventilation/perfusion (V/P) mismatch in lung scans performed on patients suspected of pulmonary embolism (PE) was evaluated. Ten of 20 patients with this scan finding were found to have PE. An intermediate probability of PE was found with segmental (71%) or subsegmental (45%) single V/P mismatches. Seven of 16 patients with a single V/P mismatch and without a matching radiographic opacity had PE. Three of the four patients who had a V/P mismatch and a matching radiographic opacity were found to have PE. Multiview ventilation imaging with 81mKr was found to have advantages for the evaluation of single V/P mismatches. Based on the data available at this time, a single V/P mismatch suggests an intermediate probability of PE.

  2. Perfusion lung scintigraphy for the prediction of postoperative residual pulmonary function in patients with lung cancer.

    PubMed

    Kovacević-Kuśmierek, Katarzyna; Kozak, Józef; Pryt, Łukasz; Bieńkiewicz, Małgorzata; Cichocki, Paweł; Kuśmierek, Jacek; Płachcińska, Anna

    2015-01-01

    Accurate prediction of postoperative pulmonary function in patients with non-small cell lung cancer is crucial for proper qualification for surgery, the only effective therapeutic method. The aim of the study was to select the most accurate method for acquisition and processing of lung perfusion scintigraphy (LPS) combined with spirometry for prediction of postoperative pulmonary function in patients qualified for surgery. LPS was performed in 70 patients (40 males, 30 females), with preoperative spirometry (mean FEV1preop = 2.26 ± 0.72 L), after administration of 185 MBq of 99mTc-microalbumin/macroaggregate, using planar (appa) and SPECT/CT methods. Predicted postoperative lung function (FEV1pred) was calculated as a part of active lung parenchyma to remain after surgery. A non-imaging segment counting method was also applied. FEV1pred(appa, SPECT, SPECT/CT, segm.) were further compared with actual FEV1postop values obtained from postoperative spirometry. In the whole studied group (47 lobectomies, 23 pneumonectomies) mean value of FEV1postop was equal to 1.76 (± 0.56) L. FEV1pred(appa, SPECT, SPECT/CT, segm.) were equal to 1.75 (± 0.58) L, 1.71 (± 0.57) L, 1.72 (± 0.57) L and 1.57 (± 0.58) L, respectively. A segment counting method systematically lowered predicted FEV1 values (p < 10-5). Moreover, in 31 patients with FEV1preop < 2 L error of predicted values was assessed with Bland-Altman method. Mean absolute differences FEV1postop - FEV1pred amounted to: appa - (0.04 ± 0.13) L, SPECT - (0.07 ± 0.14) L, SPECT/CT - (0.06 ± 0.14) L and segm. - (0.21 ± 0.19) L, respectively. Lower limit of 95% confidence interval calculated for planar - optimal method, was equal to -220 mL (also determined separately in subgroups after lobectomy and pneumonectomy). This study shows that planar LPS may be applied for prediction of postoperative pulmonary function in patients qualified for pneumonectomy and lobectomy. If actual FEV1postop value is to be ≥ 800 m

  3. 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.

  4. Hybrid detection of lung nodules on CT scan images

    SciTech Connect

    Lu, Lin; Tan, Yongqiang; Schwartz, Lawrence H.; Zhao, Binsheng

    2015-09-15

    Purpose: The diversity of lung nodules poses difficulty for the current computer-aided diagnostic (CAD) schemes for lung nodule detection on computed tomography (CT) scan images, especially in large-scale CT screening studies. We proposed a novel CAD scheme based on a hybrid method to address the challenges of detection in diverse lung nodules. Methods: The hybrid method proposed in this paper integrates several existing and widely used algorithms in the field of nodule detection, including morphological operation, dot-enhancement based on Hessian matrix, fuzzy connectedness segmentation, local density maximum algorithm, geodesic distance map, and regression tree classification. All of the adopted algorithms were organized into tree structures with multi-nodes. Each node in the tree structure aimed to deal with one type of lung nodule. Results: The method has been evaluated on 294 CT scans from the Lung Image Database Consortium (LIDC) dataset. The CT scans were randomly divided into two independent subsets: a training set (196 scans) and a test set (98 scans). In total, the 294 CT scans contained 631 lung nodules, which were annotated by at least two radiologists participating in the LIDC project. The sensitivity and false positive per scan for the training set were 87% and 2.61%. The sensitivity and false positive per scan for the testing set were 85.2% and 3.13%. Conclusions: The proposed hybrid method yielded high performance on the evaluation dataset and exhibits advantages over existing CAD schemes. We believe that the present method would be useful for a wide variety of CT imaging protocols used in both routine diagnosis and screening studies.

  5. 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

  6. Improvement in Ventilation-Perfusion Mismatch after Bronchoscopic Lung Volume Reduction: Quantitative Image Analysis.

    PubMed

    Lee, Sei Won; Lee, Sang Min; Shin, So Youn; Park, Tai Sun; Oh, Sang Young; Kim, Namkug; Hong, Yoonki; Lee, Jae Seung; Oh, Yeon-Mok; Lee, Sang-Do; Seo, Joon Beom

    2017-10-01

    Purpose To evaluate whether bronchoscopic lung volume reduction (BLVR) increases ventilation and therefore improves ventilation-perfusion (V/Q) mismatch. Materials and Methods All patients provided written informed consent to be included in this study, which was approved by the Institutional Review Board (2013-0368) of Asan Medical Center. The physiologic changes that occurred after BLVR were measured by using xenon-enhanced ventilation and iodine-enhanced perfusion dual-energy computed tomography (CT). Patients with severe emphysema plus hyperinflation who did not respond to usual treatments were eligible. Pulmonary function tests, the 6-minute walking distance (6MWD) test, quality of life assessment, and dual-energy CT were performed at baseline and 3 months after BLVR. The effect of BLVR was assessed with repeated-measures analysis of variance. Results Twenty-one patients were enrolled in this study (median age, 68 years; mean forced expiratory volume in 1 second [FEV1], 0.75 L ± 0.29). After BLVR, FEV1 (P < .001) and 6MWD (P = .002) improved significantly. Despite the reduction in lung volume (-0.39 L ± 0.44), both ventilation per voxel (P < .001) and total ventilation (P = .01) improved after BLVR. However, neither perfusion per voxel (P = .16) nor total perfusion changed significantly (P = .49). Patients with lung volume reduction of 50% or greater had significantly better improvement in FEV1 (P = .02) and ventilation per voxel (P = .03) than patients with lung volume reduction of less than 50%. V/Q mismatch also improved after BLVR (P = .005), mainly owing to the improvement in ventilation. Conclusion The dual-energy CT analyses showed that BLVR improved ventilation and V/Q mismatch. This increased lung efficiency may be the primary mechanism of improvement after BLVR, despite the reduction in lung volume. (©) RSNA, 2017 Online supplemental material is available for this article.

  7. Does perfusion CT play a role in the evaluation of percutaneous microwave-ablated lung tumours?

    PubMed

    Parvizi, N; Chung, D; Little, M W; Gleeson, F V; Anderson, E M

    2016-11-01

    To assess the clinical utility of perfusion computed tomography (pCT) parameters in microwave ablation (MWA) of lung tumours. Patients were included who had primary or metastatic lung tumours and underwent pCT studies immediately pre- and post-MWA. Perfusion maps of the tumours were constructed using CT perfusion software (GE, Milwaukee, WI, USA). Regions of interest were drawn on sequential axial sections to extract the pCT parameters, blood volume (BV), average blood flow (BF), and mean transit time (MTT) from the entire tumour volume. Direct visualisation of perfusion maps were performed by two experienced readers blinded to outcome. Data were analysed using the Mann-Whitney test. Thirty-one patients with 34 lung tumours had follow-up data at 12 months. The median tumour diameter was 19 mm (10-52 mm). Seven patients developed local tumour progression (LTP) at 12 months. There was no statistical difference between patients with LTP and complete treatment based on quantitative pCT parameters. Using radiologist visualisation of perfusion maps, there was moderate agreement between the two readers (kappa coefficient 0.53) with a combined 96% sensitivity, 62% specificity, 91% positive predictive value, and 80% negative predictive value. Quantitative pCT parameters do not help differentiate between LTP and complete treatment, but subjective analysis of perfusion maps may be a useful assessment tool for identifying treatment adequacy potentially enabling identification of areas requiring further treatment at the time of the procedure. Copyright © 2016 The Royal College of Radiologists. All rights reserved.

  8. Ex vivo lung perfusion with adenosine A2A receptor agonist allows prolonged cold preservation of lungs donated after cardiac death.

    PubMed

    Wagner, Cynthia E; Pope, Nicolas H; Charles, Eric J; Huerter, Mary E; Sharma, Ashish K; Salmon, Morgan D; Carter, Benjamin T; Stoler, Mark H; Lau, Christine L; Laubach, Victor E; Kron, Irving L

    2016-02-01

    Ex vivo lung perfusion has been successful in the assessment of marginal donor lungs, including donation after cardiac death (DCD) donor lungs. Ex vivo lung perfusion also represents a unique platform for targeted drug delivery. We sought to determine whether ischemia-reperfusion injury would be decreased after transplantation of DCD donor lungs subjected to prolonged cold preservation and treated with an adenosine A2A receptor agonist during ex vivo lung perfusion. Porcine DCD donor lungs were preserved at 4°C for 12 hours and underwent ex vivo lung perfusion for 4 hours. Left lungs were then transplanted and reperfused for 4 hours. Three groups (n = 4/group) were randomized according to treatment with the adenosine A2A receptor agonist ATL-1223 or the dimethyl sulfoxide vehicle: Infusion of dimethyl sulfoxide during ex vivo lung perfusion and reperfusion (DMSO), infusion of ATL-1223 during ex vivo lung perfusion and dimethyl sulfoxide during reperfusion (ATL-E), and infusion of ATL-1223 during ex vivo lung perfusion and reperfusion (ATL-E/R). Final Pao2/Fio2 ratios (arterial oxygen partial pressure/fraction of inspired oxygen) were determined from samples obtained from the left superior and inferior pulmonary veins. Final Pao2/Fio2 ratios in the ATL-E/R group (430.1 ± 26.4 mm Hg) were similar to final Pao2/Fio2 ratios in the ATL-E group (413.6 ± 18.8 mm Hg), but both treated groups had significantly higher final Pao2/Fio2 ratios compared with the dimethyl sulfoxide group (84.8 ± 17.7 mm Hg). Low oxygenation gradients during ex vivo lung perfusion did not preclude superior oxygenation capacity during reperfusion. After prolonged cold preservation, treatment of DCD donor lungs with an adenosine A2A receptor agonist during ex vivo lung perfusion enabled Pao2/Fio2 ratios greater than 400 mm Hg after transplantation in a preclinical porcine model. Pulmonary function during ex vivo lung perfusion was not predictive of outcomes after transplantation. Copyright

  9. Quantification of lung perfusion blood volume (lung PBV) by dual-energy CT in pulmonary embolism before and after treatment: preliminary results.

    PubMed

    Nagayama, Hiroki; Sueyoshi, Eijun; Hayashida, Takeshi; Ashizawa, Kazuto; Sakamoto, Ichiro; Uetani, Masataka

    2013-01-01

    The purpose was to investigate the quantification of lung perfusion blood volume (PBV) by dual-energy computed tomography (CT) in patients with pulmonary embolism (PE) before and after treatment. Twenty-five patients with PE underwent dual-energy CT angiography before and after treatment. In all 25 patients, pulmonary CT confirmed that there was no PE after treatment. This preliminary study demonstrated the possibility that quantification of lung PBV may reflect parenchymal arterial perfusion before and after treatment, including the compensatory increase of lung perfusion.

  10. Visualization of retinal vascular structure and perfusion with a nonconfocal adaptive optics scanning light ophthalmoscope

    PubMed Central

    Sulai, Yusufu N.; Scoles, Drew; Harvey, Zachary; Dubra, Alfredo

    2015-01-01

    Imaging of the retinal vascular structure and perfusion was explored by confocal illumination and nonconfocal detection in an adaptive optics scanning light ophthalmoscope (AOSLO), as an extension of the work by Chui et al. [Biomed. Opt. Express 3, 2537 (2012)]. Five different detection schemes were evaluated at multiple retinal locations: circular mask, annular mask, circular mask with filament, knife-edge, and split-detector. Given the superior image contrast in the reflectance and perfusion maps, the split-detection method was further tested using pupil apodization, polarized detection, and four different wavelengths. None of these variations provided noticeable contrast improvement. The noninvasive visualization of capillary flow and structure provided by AOSLO split-detection shows great promise for studying ocular and systemic conditions that affect the retinal vasculature. PMID:24690655

  11. 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.

  12. Marked differences between prone and supine sheep in effect of PEEP on perfusion distribution in zone II lung.

    PubMed

    Walther, Sten M; Johansson, Mats J; Flatebø, Torun; Nicolaysen, Anne; Nicolaysen, Gunnar

    2005-09-01

    The classic four-zone model of lung blood flow distribution has been questioned. We asked whether the effect of positive end-expiratory pressure (PEEP) is different between the prone and supine position for lung tissue in the same zonal condition. Anesthetized and mechanically ventilated prone (n = 6) and supine (n = 5) sheep were studied at 0, 10, and 20 cm H2O PEEP. Perfusion was measured with intravenous infusion of radiolabeled 15-microm microspheres. The right lung was dried at total lung capacity and diced into pieces (approximately 1.5 cm3), keeping track of the spatial location of each piece. Radioactivity per unit weight was determined and normalized to the mean value for each condition and animal. In the supine posture, perfusion to nondependent lung regions decreased with little relative perfusion in nondependent horizontal lung planes at 10 and 20 cm H2O PEEP. In the prone position, the effect of PEEP was markedly different with substantial perfusion remaining in nondependent lung regions and even increasing in these regions with 20 cm H2O PEEP. Vertical blood flow gradients in zone II lung were large in supine, but surprisingly absent in prone, animals. Isogravitational perfusion heterogeneity was smaller in prone than in supine animals at all PEEP levels. Redistribution of pulmonary perfusion by PEEP ventilation in supine was largely as predicted by the zonal model in marked contrast to the findings in prone. The differences between postures in blood flow distribution within zone II strongly indicate that factors in addition to pulmonary arterial, venous, and alveolar pressure play important roles in determining perfusion distribution in the in situ lung. We suggest that regional variation in lung volume through the effect on vascular resistance is one such factor and that chest wall conformation and thoracic contents determine regional lung volume.

  13. Very low probability interpretation of V/Q lung scans in combination with low probability objective clinical assessment reliably excludes pulmonary embolism: data from PIOPED II.

    PubMed

    Gottschalk, Alexander; Stein, Paul D; Sostman, H Dirk; Matta, Fadi; Beemath, Afzal

    2007-09-01

    Use of a very low probability interpretation of ventilation/perfusion (V/Q) lung scans, if verified by prospective evaluation to have a low positive predictive value (PPV), will reduce the number of nondiagnostic interpretations of V/Q scans and may be particularly useful in patients with a relative contraindication to CT. The purpose of this investigation was to test the hypothesis that a very low probability interpretation of the V/Q scan has a PPV of <10%. Data are from PIOPED II (Prospective Investigation of Pulmonary Embolism Diagnosis II). Very low probability criteria are (a) nonsegmental perfusion abnormalities, (b) perfusion defect smaller than corresponding radiographic lesion, (c) > or =2 matched V/Q defects with regionally normal chest radiograph, (d) 1-3 small segmental perfusion defects (<25% of a segment), (e) solitary triple matched defect in middle or upper lung zones, (f) stripe sign around the perfusion defect(s), and (g) perfusion defect from pleural effusion equal to one third or more of the pleural cavity with no other perfusion defect. A very low probability consensus interpretation of the V/Q scan was made in 56% of patients. The PPV of a very low probability interpretation of the V/Q scans was 36 of 440 patients (8.2%). Among patients with suspected pulmonary embolism who had a low clinical probability objective clinical assessment and a very low probability V/Q scan, the PPV was 8 of 259 patients (3.1%). Among women < or =40 y, the PPV of the very low probability V/Q with a low objective clinical assessment was 1 of 50 (2%). The very low probability V/Q scan together with a low probability clinical assessment reliably excludes pulmonary embolism.

  14. Generation of parametric images during routine Tc-99m PYP inhalation/Tc-99m MAA perfusion lung scintigraphy. Technical note.

    PubMed

    Miron, S D; Wiesen, E J; Feiglin, D H; Cohen, A M; Bellon, E M

    1991-07-01

    A simple technique is described for generating ventilation/perfusion ratio and perfusion/ventilation ratio images from the posterior Tc-99m PYP aerosol inhalation and Tc-99m MAA perfusion images obtained during routine lung scintigraphy. These images highlight areas of ventilation/perfusion incongruence--mismatch or reverse mismatch--that may sometimes be difficult to detect on conventional images.

  15. Isolated total lung perfusion as a means to deliver organ-specific chemotherapy: long-term studies in animals

    SciTech Connect

    Johnston, M.R.; Christensen, C.W.; Minchin, R.F.; Rickaby, D.A.; Linehan, J.H.; Schuller, H.M.; Boyd, M.R.; Dawson, C.A.

    1985-07-01

    The objectives of this study were to develop a surgical procedure that would allow for bilateral isolated lung perfusion in vivo as a means of delivering organ-specific chemotherapy and to evaluate the influence of the procedure on certain pulmonary physiologic parameters. The sterile surgical procedure that was carried out in dogs involved the setting up of two separate perfusion circuits. Once standard systemic cardiopulmonary bypass was established, a second circuit was devised to perfuse the lungs by placing an inflow cannula into the main pulmonary artery and collecting venous effluent in the left atrium. Cross-contamination between perfusion circuits was determined in acute studies with labeled plasma protein or red blood cells and was found to be in an acceptable range if the aorta was cross-clamped and the heart arrested. Only about 0.4 ml/min of pulmonary perfusate leaked into the systemic circulation, indicating that systemic toxicity should not be a major concern when chemotherapy agents are added to the pulmonary perfusate. Chronic studies demonstrated that hemodynamic parameters, lung water, pulmonary endothelial serotonin extraction, and histologic findings all showed minimal changes after 50 minutes of isolated lung perfusion. Five days after perfusion, lung dynamic compliance and peak serotonin extraction showed significant decreases. However, all of the measured parameters had returned toward baseline levels by the end of the 8-week postoperative study period. The procedure offers significant advantages over the previously described single lung perfusion and may provide a method of delivering immediate high-concentration adjuvant chemotherapy to coincide with resection of primary or metastatic lung tumors.

  16. Radioisotope scanning of brain, liver, lung and bone with a note on tumour localizing agents

    PubMed Central

    Lavender, J. P.

    1973-01-01

    Radioisotopic scanning of brain, liver, lungs and the skeleton is briefly reviewed with a survey of recent developments of clinical significance. In brain scanning neoplasm detection rates of greater than 90% are claimed. The true figure is probably 70-80%. Autopsy data shows a number of false negatives, particularly with vascular lesions. Attempts to make scanning more specific in differentiating neoplasm from vascular lesions by rapid sequence blood flow studies are reviewed. In liver scanning by means of colloids again high success rate is claimed but small metastases are frequently missed and the false negative scan rate is probably quite high. Lung scanning still has its main place in investigating pulmonary embolic disease. Ventilation studies using Xenon 133 are useful, particularly combined with perfusion studies. The various radiopharmaceuticals for use in bone scanning are reviewed. The appearance of technetium labelled phosphate compounds will probably allow much wider use of total skeletal scanning. Research into tumour localizing agents continues, the most recent and interesting being Gallium citrate and labelled bleomycin. Neither agent is predictable however although Gallium may have a place in Hodgkins disease and bronchogenic neoplasm and both may have a place in the detection of cerebral tumours. ImagesFig. 1Fig. 2Fig. 3p452-bFig. 3bFig. 4Fig. 5Fig. 5bFig. 6Fig. 7Fig. 8Fig. 9Fig. 10Fig. 11Fig. 12Fig. 12c & 12dFig. 13Fig. 13 b,c,dFig. 14Fig. 14bFig. 15Fig. 15bFig. 16Fig. 17Fig. 18 PMID:4602127

  17. 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.

  18. 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.

  19. 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.

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

    PubMed

    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. Bayesian SPECT lung imaging for visualization and quantification of pulmonary perfusion

    SciTech Connect

    Scarfone, C.; Jaszczak, R.J.; Gilland, D.R.; Greer, K.L.; Munley, M.T.; Marks, L.B.; Coleman, R.E.

    1998-12-01

    In this paper, the authors quantitatively and qualitatively examine the use of a Gibbs prior in maximum a posteriori (MAP) reconstruction of SPECT images of pulmonary perfusion using the expectation-maximization (EM) algorithm. This Bayesian approach is applied to SPECT projection data acquired from a realistic torso phantom with spherical defects in the lungs simulating perfusion deficits. Both the scatter subtraction constant (k) and the smoothing parameter beta ({beta}) characterizing the prior are varied to study their effect on image quality and quantification. Region of interest (ROI) analysis is used to compare MAP-EM radionuclide concentration estimates with those derived from a ``clinical`` implementation of filtered backprojection (CFBP), and a quantitative implementation of FBP (QFBP) utilizing nonuniform attenuation and scatter compensation. Qualitatively, the MAP-EM images contain reduced artifacts near the lung boundaries relative to the FBP implementations. Generally, the MAP-EM image`s visual quality and the ability to discern the areas of reduced radionuclide concentration in the lungs depend on the value of {beta} and the total number of iterations. For certain choices of {beta} and total iterations, MAP-EM lung images are visually comparable to FBP. Based on profile and ROI analysis, SPECT QFBP and MAP-EM images have the potential to provide quantitatively accurate reconstructions when compared to CFBP. The computational burden, however, is greater for the MAP-EM approach. To demonstrate the clinical efficacy of the methods, the authors present pulmonary images of a patient with lung cancer.

  2. 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.

  3. Role of inhaled nitric oxide in ischaemia-reperfusion injury in the perfused rabbit lung.

    PubMed

    Ishibe, Y; Liu, R; Ueda, M; Mori, K; Miura, N

    1999-09-01

    We have tested if inhaled nitric oxide (NO) is beneficial in ischaemia-reperfusion (IR) lung injury using an isolated perfused rabbit lung model. Ischaemia for 60 min was followed by reperfusion and ventilation with nitric oxide 40 ppm (n = 6) or without nitric oxide ventilation (n = 6) for 60 min. In the control group (n = 6), the lungs were perfused continuously for 120 min. Permeability coefficient (Kfc) and vascular resistance (PVR) were measured serially for 60 min after reperfusion. We also determined the left lung W/D ratio and measured nitric oxide metabolites (NOx) and cGMP concentrations in bronchoalveolar lavage (BAL) fluid from the right lung. IR increased Kfc, PVR and W/D followed by decreased cGMP. Ventilation with nitric oxide restored these changes by preventing the decrease in cGMP. Differences in NOx concentrations in BAL fluid between the control and IR groups were not statistically significant. Our results indicate that IR impaired pulmonary vascular function and resulted in microvascular constriction and leakage. Ventilation with nitric oxide from the beginning of the reperfusion period improved pulmonary dysfunction such as vasoconstriction and capillary leak by restoring cGMP concentrations.

  4. Automated Lung Segmentation from HRCT Scans with Diffuse Parenchymal Lung Diseases.

    PubMed

    Pulagam, Ammi Reddy; Kande, Giri Babu; Ede, Venkata Krishna Rao; Inampudi, Ramesh Babu

    2016-08-01

    Performing accurate and fully automated lung segmentation of high-resolution computed tomography (HRCT) images affected by dense abnormalities is a challenging problem. This paper presents a novel algorithm for automated segmentation of lungs based on modified convex hull algorithm and mathematical morphology techniques. Sixty randomly selected lung HRCT scans with different abnormalities are used to test the proposed algorithm, and experimental results show that the proposed approach can accurately segment the lungs even in the presence of disease patterns, with some limitations in the apices and bases of lungs. The algorithm demonstrates a high segmentation accuracy (dice similarity coefficient = 98.62 and shape differentiation metrics dmean = 1.39 mm, and drms = 2.76 mm). Therefore, the developed automated lung segmentation algorithm is a good candidate for the first stage of a computer-aided diagnosis system for diffuse lung diseases.

  5. Protease inhibitor nafamostat mesilate attenuates complement activation and improves function of xenografts in a discordant lung perfusion model.

    PubMed

    Tagawa, Tsutomu

    2011-01-01

    Anti-complement activity of nafamostat mesilate (FUT-175) is strong including its variety of pharmacological effects. The effect of FUT-175 for xenografts in an ex vivo guinea pig-to-rat lung perfusion model was evaluated. Heparinized Lewis rat blood was used to perfuse the lungs in three groups (n = 6 each). Group I used Lewis rat left lung for donor, Group X used guinea pig left lung for donor, and Group XF used guinea pig left lung for donor, which was perfused with Lewis rat blood with 0.2 mg/ml of FUT-175. Complement activity causing 50% hemolysis (CH50) in the perfusion blood and pulmonary function either before or during perfusion were serially measured. Pathological assessments of the lungs were also carried out after perfusion. The duration of satisfactory pulmonary function was significantly increased in Group XF. Complement activity causing 50% hemolysis in Group XF decreased more significantly compared to Group X. FUT-175 suppressed both the increase in pulmonary arterial pressure and airway resistance, and the decrease in dynamic lung compliance. In Group X, pathology showed intra-alveolar hemorrhage, perivascular edema, and medial thickening with endothelial swelling of the pulmonary arteries. In Group XF, less changes were observed compared to Group X. Group X showed deposition of IgM, IgG, and C3 at the endothelium of arteries, which was fewer in Group XF, and even fewer in Group I. This study suggests that FUT-175 inhibited complement activation and improved lung xenograft function. FUT-175 ameliorates hyperacute rejection in a guinea pig-to-rat ex vivo xenogeneic lung perfusion model. © 2011 John Wiley & Sons A/S.

  6. Contemporary review of the organ care system in lung transplantation: potential advantages of a portable ex-vivo lung perfusion system.

    PubMed

    Schmack, Bastian; Weymann, Alexander; Mohite, Prashant; Garcia Saez, Diana; Zych, Bartlomiej; Sabashnikov, Anton; Zeriouh, Mohamed; Schamroth, Joel; Koch, Achim; Soresi, Simona; Ananiadou, Olga; De Robertis, Fabio; Karck, Matthias; Simon, Andre Ruediger; Popov, Aron Frederik

    2016-11-01

    Lung transplantation remains the definite treatment for various end-stage lung diseases. Cold flush perfusion, the standard method for organ procurement has severe limitations. Organ Care System (OCS; TransMedics, Inc., Andover, USA) is an approved method to preserve hearts for transplantation that allows for greatly reduced cold ischemic time. Consequently, the use of an adapted OCS lung as a portable full ex-vivo lung perfusion system in lung transplantation is currently under close evaluation. Areas covered: The aim of this article is to review the advantages and the role of the OCS in the field of lung transplantation by reviewing the latest literature and evaluating this novel procurement technique in the context of conventional methods like cold flush and regular ex-vivo lung perfusion. Expert commentary: The use of OCS in the field of lung transplantation has great potential for improved patients outcomes and is justified in cases with (i) marginal donor lungs, (ii) foreseeable long time of transportation (iii) high-risk recipient or donor /recipient profiles, particularly in the setting of an overall increasing need for suitable donor organs. Results from two major multi-centre prospective studies are pending to objectively assess the possible advantages of this portable ex-vivo lung perfusion system.

  7. Comparison of observer variability and accuracy of different criteria for lung scan interpretation.

    PubMed

    Hagen, Petronella J; Hartmann, Ieneke J C; Hoekstra, Otto S; Stokkel, Marcel P M; Postmus, Pieter E; Prins, Martin H

    2003-05-01

    Different criteria have been advocated for the interpretation of ventilation/perfusion (V/Q) lung scans in patients with suspected pulmonary embolism (PE). Besides these predefined criteria, many physicians use an integration of the different sets of criteria and their own experience-the so-called Gestalt interpretation. The purpose of this study was to evaluate interobserver variability and accuracy of 3 sets of criteria: the Hull and PIOPED (Prospective Investigation of Pulmonary Embolism Diagnosis) criteria and the Gestalt interpretation. Two experienced observers interpreted V/Q scans of all 328 patients according to the 3 different schemes. The diagnostic classification obtained for the different sets of criteria was analyzed against the presence or absence of PE. The interobserver variabilities as assessed by the kappa statistics of the PIOPED and Hull criteria and for the Gestalt interpretation were 0.70 (95% confidence interval [CI], 0.64-0.76), 0.79 (95% CI, 0.73-0.85), and 0.65 (95% CI, 0.58-0.72), respectively. The differences in kappa values between the Hull and PIOPED criteria and between the Hull criteria and Gestalt interpretation were statistically significant (P < 0.05 and P < 0.001, respectively). For 16 patients (14 without PE) with a normal lung scan result according to the Hull criteria, the result according to the PIOPED criteria was low probability. For 21 patients (12 with PE), the scans were intermediate probability according to the PIOPED criteria, whereas the result with the Hull criteria was high probability. Analysis of receiver-operating-characteristic curves yielded a comparable area under the curve for all sets of criteria (0.87-0.90). The Hull, PIOPED, and Gestalt interpretation of V/Q lung scans all have a good accuracy and interobserver variability. However, the reproducibility of the Hull criteria is superior in comparison with that of the other sets of criteria.

  8. 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

  9. 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.

  10. Early results in transplantation of initially rejected donor lungs after ex vivo lung perfusion: a case-control study.

    PubMed

    Wallinder, Andreas; Ricksten, Sven-Erik; Silverborn, Martin; Hansson, Christoffer; Riise, Gerdt C; Liden, Hans; Jeppsson, Anders; Dellgren, Göran

    2014-01-01

    An increasing number of studies have shown that ex vivo lung perfusion (EVLP) is safe and that rejected donor lungs can be resuscitated and used for lung transplantation (LTx). Early clinical outcomes in patients transplanted with reconditioned lungs at our centre were reviewed and compared with those of contemporary non-EVLP controls. During 18 months starting January 2011, 11 pairs of donor lungs initially deemed unsuitable for transplantation underwent EVLP. Haemodynamic (pulmonary flow, vascular resistance and artery pressure) and respiratory (peak airway pressure and compliance) parameters were analysed during evaluation. Lungs that improved (n = 11) to meet International Society of Heart and Lung Transplantation criteria were transplanted and compared with patients transplanted with non-EVLP lungs (n = 47) during the same time period. Donor lungs were initially rejected due to either inferior PaO2/FiO2 ratio (n = 9), bilateral infiltrate on chest X-ray (n = 1) or ongoing extra corporeal membrane oxygenation (n = 1). The donor lungs improved from a mean PaO2/FiO2 ratio of 27.9 kPa in the donor to a mean of 59.6 kPa at the end of the EVLP (median improvement 28.4 kPa, range 21.0-50.7 kPa). Two single lungs were deemed unsuitable and not used for LTx. Eleven recipients from the regular waiting list underwent either single (n = 3) LTx or double (n = 8) LTx with EVLP-treated lungs. The median time to extubation (12 (range, 3-912) vs 6 (range, 2-1296) h) and median intensive care unit (ICU) stay (152 (range, 40-625) vs 48 (range, 22-1632) h) were longer in the EVLP group (P = 0.05 and P = 0.01, respectively). There were no differences in length of hospital stay (median 28 (range 25-93) vs 28 (18-209), P = 0.21). Two patients in the EVLP group and 6 in the control group had primary graft dysfunction >Grade 1 at 72 h postoperatively. Three patients in the control group died before discharge. All recipients of EVLP lungs were discharged alive from hospital. The use of

  11. Ex Vivo Lung Perfusion in the Rat: Detailed Procedure and Videos

    PubMed Central

    Lonati, Caterina; Brambilla, Daniela; Rapido, Francesca; Valenza, Franco; Gatti, Stefano

    2016-01-01

    Ex vivo lung perfusion (EVLP) is a promising procedure for evaluation, reconditioning, and treatment of marginal lungs before transplantation. Small animal models can contribute to improve clinical development of this technique and represent a substantial platform for bio-molecular investigations. However, to accomplish this purpose, EVLP models must sustain a prolonged reperfusion without pharmacological interventions. Currently available protocols only partly satisfy this need. The aim of the present research was accomplishment and optimization of a reproducible model for a protracted rat EVLP in the absence of anti-inflammatory treatment. A 180 min, uninjured and untreated perfusion was achieved through a stepwise implementation of the protocol. Flow rate, temperature, and tidal volume were gradually increased during the initial reperfusion phase to reduce hemodynamic and oxidative stress. Low flow rate combined with open atrium and protective ventilation strategy were applied to prevent lung damage. The videos enclosed show management of the most critical technical steps. The stability and reproducibility of the present procedure were confirmed by lung function evaluation and edema assessment. The meticulous description of the protocol provided in this paper can enable other laboratories to reproduce it effortlessly, supporting research in the EVLP field. PMID:27936178

  12. Increasing the accuracy of lung perfusion scintigraphy in children with bidirectional Glenn circulation.

    PubMed

    Fukuda, Yutaka; Momoi, Nobuo; Mitomo, Masaki; Aoyagi, Yoshimichi; Endo, Kisei; Matsumoto, Ayumi; Hosoya, Mitsuaki

    2010-12-01

    In children who have undergone a bidirectional Glenn procedure without antegrade or additional pulmonary blood flow, we have often noted a discrepancy between apparent lung perfusion on scintigraphy and superior vena cava angiography when evaluating right and left pulmonary blood flow. We found a tendency for radionuclide, tracer 99mTc-MAA, when administered through a single upper extremity vein, to preferentially accumulate in the ipsilateral lung. In the present study, we examined whether the ratio of right-to-left pulmonary flow varied when 99mTc-MAA was administered via either the right upper or the left upper extremity vein. We studied six children (median age 1.3 ± 0.23 years) who underwent a bidirectional Glenn before total cavopulmonary connection. Five children who underwent biventricular repair served as a control. Perfusion scintigraphy using 99mTc-labeled macroaggregated albumin (99mTc-MAA) was performed in all children. First, we injected radionuclide via the right upper extremity and calculated the pulmonary accumulation in both lungs (R-image). Second, we injected the same dose of radionuclide via the left upper extremity and calculated the pulmonary accumulation (B-image), which represented the resulting administration via both upper extremities. The lung accumulation that resulted from radionuclide administration via the left upper extremity (L-image) was determined by subtracting the R-image from the B-image. We evaluated the right-to-total pulmonary blood flow ratio (radionuclide accumulation in right lung / radionuclide accumulation in both lungs) in the R-, L- and B-images. The right-to-total pulmonary blood flow ratios in the R-, L- and B-images were 815 ± 15.3%, 39.8 ± 11.7% and 61.3 ± 11.8%, respectively, and there were significant differences among the three images (P < 0.01). On the other hand, in the control group, the right-to-total pulmonary blood flow ratios in the R-, L- and B-images were 59.3 ± 22.4%, 57.8 ± 26.4% and 58.8

  13. 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.

  14. Activation of rho is involved in the mechanism of hydrogen-peroxide-induced lung edema in isolated perfused rabbit lung.

    PubMed

    Chiba, Y; Ishii, Y; Kitamura, S; Sugiyama, Y

    2001-09-01

    Acute lung injury is attributed primarily to increased vascular permeability caused by reactive oxygen species derived from neutrophils, such as hydrogen peroxide (H2O2). Increased permeability is accompanied by the contraction and cytoskeleton reorganization of endothelial cells, resulting in intercellular gap formation. The Rho family of Ras-like GTPases is implicated in the regulation of the cytoskeleton and cell contraction. We examined the role of Rho in H2O2-induced pulmonary edema with the use of isolated perfused rabbit lungs. To our knowledge, this is the first study to examine the role of Rho in increased vascular permeability induced by H2O2 in perfused lungs. Vascular permeability was evaluated on the basis of the capillary filtration coefficient (Kfc, ml/min/cm H2O/100 g). We found that H2O2 (300 microM) increased lung weight, Kfc, and pulmonary capillary pressure. These effects of H2O2 were abolished by treatment with Y-27632 (50 microM), an inhibitor of the Rho effector p160 ROCK. In contrast, the muscular relaxant papaverine inhibited the H2O2-induced rise in pulmonary capillary pressure, but did not suppress the increases in lung weight and Kfc. These findings indicate that H2O2 causes pulmonary edema by elevating hydrostatic pressure and increasing vascular permeability. Y-27632 inhibited the formation of pulmonary edema by blocking both of these H2O2-induced effects. Our results suggest that Rho-related pathways have a part in the mechanism of H2O2-induced pulmonary edema. Copyright 2001 Academic Press.

  15. Vibration-response imaging versus quantitative perfusion scintigraphy in the selection of patients for lung-resection surgery.

    PubMed

    Comce, Fatma; Bingol, Zuleyha; Kiyan, Esen; Tanju, Serhan; Toker, Alper; Cagatay, Pembe; Ece, Turhan

    2011-12-01

    In patients being considered for lung-resection surgery, quantitative perfusion scintigraphy is used to predict postoperative lung function and guide the determination of lung-resection candidacy. Vibration-response imaging has been proposed as a noninvasive, radiation-free, and simpler method to predict postoperative lung function. We compared vibration-response imaging to quantitative perfusion scintigraphy for predicting postoperative FEV(1) and diffusing capacity of the lung for carbon monoxide (D(LCO)). We enrolled 35 candidates for lung resection. Twenty-five patients had preoperative FEV(1) and D(LCO) MEASUREMENTS: The vibration-response-imaging measurements showed strong correlation with the quantitative-perfusion-scintigraphy measurements of predicted postoperative FEV(1)% (r = 0.87, P < .001), predicted postoperative FEV(1) (r = 0.90, P < .001), and predicted postoperative D(LCO)% (r = 0.90, P < .001). There was a correlation between predicted postoperative FEV(1) (% and L) measured via quantitative perfusion scintigraphy and the actual postoperative FEV(1) (% and L) (r = 0.47, P = .048, r = 0.73, P < .001). There was no difference between the vibration-response-imaging measurements and the actual postoperative measurements of predicted postoperative FEV(1) (% and L). There was a correlation between predicted postoperative FEV(1) (% and L) measured via vibration-response imaging and actual postoperative FEV(1) (% and L) (r = 0.52, P = .044, r = 0.79, P < .001). The mean differences between the predicted and actual postoperative FEV(1) values were 49 mL with vibration-response imaging, versus 230 mL with quantitative perfusion scintigraphy. Neither the vibration-response imaging nor the quantitative perfusion scintigraphy predicted postoperative D(LCO)% values agreed with the actual postoperative D(LCO)% values. Vibration-response imaging may be a good alternative to quantitative perfusion scintigraphy in evaluating lung-resection candidacy.

  16. 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

  17. Detection of reactive oxygen species in isolated, perfused lungs by electron spin resonance spectroscopy

    PubMed Central

    Weissmann, Norbert; Kuzkaya, Nermin; Fuchs, Beate; Tiyerili, Vedat; Schäfer, Rolf U; Schütte, Hartwig; Ghofrani, Hossein A; Schermuly, Ralph T; Schudt, Christian; Sydykov, Akylbek; Egemnazarow, Bakytbek; Seeger, Werner; Grimminger, Friedrich

    2005-01-01

    Background The sources and measurement of reactive oxygen species (ROS) in intact organs are largely unresolved. This may be related to methodological problems associated with the techniques currently employed for ROS detection. Electron spin resonance (ESR) with spin trapping is a specific method for ROS detection, and may address some these technical problems. Methods We have established a protocol for the measurement of intravascular ROS release from isolated buffer-perfused and ventilated rabbit and mouse lungs, combining lung perfusion with the spin probe l-hydroxy-3-carboxy-2,2,5,5-tetramethylpyrrolidine (CPH) and ESR spectroscopy. We then employed this technique to characterize hypoxia-dependent ROS release, with specific attention paid to NADPH oxidase-dependent superoxide formation as a possible vasoconstrictor pathway. Results While perfusing lungs with CPH over a range of inspired oxygen concentrations (1–21 %), the rate of CP• formation exhibited an oxygen-dependence, with a minimum at 2.5 % O2. Addition of superoxide dismutase (SOD) to the buffer fluid illustrated that a minor proportion of this intravascular ROS leak was attributable to superoxide. Stimulation of the lungs by injection of phorbol-12-myristate-13-acetate (PMA) into the pulmonary artery caused a rapid increase in CP• formation, concomitant with pulmonary vasoconstriction. Both the PMA-induced CPH oxidation and the vasoconstrictor response were largely suppressed by SOD. When the PMA challenge was performed at different oxygen concentrations, maximum superoxide liberation and pulmonary vasoconstriction occurred at 5 % O2. Using a NADPH oxidase inhibitor and NADPH-oxidase deficient mice, we illustrated that the PMA-induced superoxide release was attributable to the stimulation of NADPH oxidases. Conclusion The perfusion of isolated lungs with CPH is suitable for detection of intravascular ROS release by ESR spectroscopy. We employed this technique to demonstrate that 1) PMA

  18. [Value of the 'non-diagnostic' lung scan--further classification as to the risk of pulmonary embolism not reliable].

    PubMed

    Broekhuizen-de Gast, H S; Tiel-van Buul, M M; Ubbink, M; van Eck-Smit, B L; Büller, H R; van Beek, E J

    2000-08-05

    To determine to what extent the 'non-diagnostic' lung scans made because of a clinical suspicion of pulmonary embolism enable further determination of the risk of pulmonary embolism. Retrospective. All non-diagnostic lung perfusion ventilation scans made in the Academic Medical Centre of Amsterdam in 1997 of 114 patients in succession (55 males and 59 females aged 27-85 years) were subjected to blind and independent re-evaluation by three observers (an experienced nuclear medicine expert, an experienced and an inexperienced intern) who, using a lung segment chart, estimated the risk of embolism as < 25%, 25-50%, 50-75% and > 75%. They did this first without and then with the chest X-ray. The findings were grouped on the basis of accordance or non-accordance with the pulmonary angiogram. The interobserver agreement was calculated by means of kappa statistics. Of 58 patients the lung scan could be compared with a chest X-ray and a pulmonary angiogram. In 43 patients with a normal angiogram the observers in an average of 50% of the scans estimated the risk of pulmonary embolism as < 25%, as against 25-50% in 27%, 50-75% in 9% and > 75% in 5%. In 15 patients with a deviant pulmonary angiogram, these figures were 22%, 38%, 20%, and 12%, respectively. The interobserver kappa for evaluation without chest X-ray was < or = 0.16, as against < or = 0.41% with the chest X-ray. A reliable classification of the risk of pulmonary embolism was not possible on the basis of non-diagnostic lung scans, regardless of whether the patient did or did not have pulmonary embolism. The interobserver variability was less when the lung scan was evaluated together with the chest X-ray, but even so it was unacceptably high.

  19. Effect of perfusate hematocrit on urea permeability-surface area in isolated dog lung

    SciTech Connect

    Parker, R.E.; Roselli, R.J.; Haselton, F.R.; Harris, T.R.

    1986-10-01

    Seven dog lower left lung lobes were statically inflated and perfused at a constant rate for each lobe with a perfusate in which the hematocrit was altered over a wide range. The permeability-surface area of urea was calculated from multiple indicator dilution curves using two separate injectates for each hematocrit level. One injectate contained only /sup 125/I-albumin as the vascular reference tracer and the other contained both /sup 51/Cr-erythrocytes and /sup 125/I-albumin as the vascular reference tracers; both contained (/sup 14/C)urea as the permeating tracer. The results strongly indicate that the phenomenon of erythrocyte trapping of urea does not affect the calculation of urea permeability-surface area product provided the appropriate albumin-erythrocyte composite reference tracer is utilized in its calculation.

  20. Pulmonary hypertension leads to a loss of gravity dependent redistribution of regional lung perfusion: a SPECT/CT study.

    PubMed

    Lau, Edmund Mt; Bailey, Dale L; Bailey, Elizabeth A; Torzillo, Paul J; Roach, Paul J; Schembri, Geoffrey P; Corte, Tamera J; Celermajer, David S

    2014-01-01

    Pre-capillary pulmonary hypertension (PHT) is characterised by progressive pulmonary vascular obliteration and loss of vascular reserves. In health, regional lung perfusion redistributes under the influence of gravity due to the presence of recruitable vessels. We investigated a combined single photon emission computed tomography/CT (SPECT/CT) method for assessing the pulmonary circulation by quantifying the gravity dependent redistribution of lung perfusion. Characterisation of patients versus healthy controls. 15 patients with pre-capillary PHT and 11 healthy controls. University hospital clinic. Regional lung perfusion was measured using SPECT/CT in two different postures (supine vs upright). A perfusion redistribution index (PRI) was used to quantify the cranial-caudal shift in regional lung perfusion resulting from gravitational (postural) change. PRI was compared between cases and controls, and correlated with markers of disease severity in cases. Patients with pre-capillary PHT had notably reduced PRI compared to controls (0.02±0.06 vs. 0.28±0.15 normalised perfusion/cm, p<0.0001). PRI was significantly associated with prognostic parameters such as 6 min walk distance (r=0.60, p=0.018), functional class (p=0.008), and tricuspid annular plane systolic excursion (r=0.58, p=0.022). The receiver operating characteristic curve showed that PRI differentiated patients with pre-capillary PHT from controls with AUC=0.94 (p<0.001). With SPECT/CT, gravity dependent redistribution of lung perfusion can be quantified using the PRI derived from supine and upright perfusion analysis. The potential utility of PRI for the non-invasive detection of PHT and assessment of disease severity warrants further study.

  1. Bronchodilator Inhalation During Ex Vivo Lung Perfusion Improves Posttransplant Graft Function After Warm Ischemia.

    PubMed

    Hijiya, Kyoko; Chen-Yoshikawa, Toyofumi F; Kondo, Takeshi; Motoyama, Hideki; Ohsumi, Akihiro; Nakajima, Daisuke; Sakamoto, Jin; Ohata, Keiji; Takahashi, Mamoru; Tanaka, Satona; Miyamoto, Ei; Aoyama, Akihiro; Date, Hiroshi

    2017-02-01

    We hypothesized that an injured lung graft from donation after cardiac death donors could be reconditioned before transplantation using an ex vivo lung perfusion (EVLP) system and ventilation with high-dose short-acting β2-adrenergic receptor agonists. Cardiac arrest was induced in a canine model by intravenous potassium chloride injection. Lungs were randomly assigned to two groups after 150 minutes of warm ischemia: inhalation of 1,400 μg of procaterol (BETA group, n = 5) or control group receiving solvent (CON group, n = 5) during EVLP. Left lungs were transplanted after 120 minutes of EVLP. Functional variables, tissue adenosine 5'-triphosphate levels, and tissue cyclic adenosine monophosphate levels were measured 240 minutes after transplantation. Physiologic pulmonary function was similar at the end of EVLP in both groups. However, significantly better graft oxygenation, dynamic pulmonary compliance, and reduced pulmonary vascular resistance were observed in the BETA group than in the CON group 240 minutes after transplantation. No severe adverse effects were observed after lung transplantation in the BETA group. Lung tissue adenosine 5'-triphosphate levels and cyclic adenosine monophosphate levels were significantly higher in the BETA group than in the CON group at the end of EVLP and at 240 minutes after transplantation. High-dose nebulized procaterol during EVLP ameliorated lung graft dysfunction at the early posttransplantation period without severe adverse effects. These data suggest that lung reconditioning with procaterol ventilation during EVLP improves lung graft function after transplantation. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  2. Influence of pulmonary regurgitation inequality on differential perfusion of the lungs in tetralogy of Fallot after repair: a phase-contrast magnetic resonance imaging and perfusion scintigraphy study.

    PubMed

    Wu, Ming-Ting; Huang, Yi-Luan; Hsieh, Kai-Sheng; Huang, Ju-Tung; Peng, Nan-Jing; Pan, Jun-Yen; Huang, Jer-Shyung; Yang, Tsung-Lung

    2007-05-08

    The purpose of this study was to evaluate the influence of pulmonary regurgitation inequality on differential perfusion of the lungs in tetralogy of Fallot (TOF) after repair. Asymmetry of lung perfusion is one of the best predictors of outcome in TOF after repair. A recent phase-contrast magnetic resonance imaging (PC-MRI) study found prominent regurgitation inequality between the bilateral pulmonary arteries in TOF after repair. Forty-three TOF post-repair patients (median age = 51 months, 31 men) received PC-MRI and 99mTc-labeled macroaggregates of albumin perfusion scintigraphy (PS) in the same day. We took PC-MRI measurements of forward flow volume (FFV), backward flow volume (BFV), and net flow volume (NFV) (NFV = FFV - BFV) and regurgitation fraction (RF) (RF = BFV/FFV) at the left and right pulmonary arteries (LPA and RPA). The differential perfusion of the left lung (L%) (L% = left lung/left + right lung) as calculated by NFV ratio, by FFV ratio of PC-MRI, and by PS were compared. The discrepancy between L% by NFV versus L% by PS was affected by the severity of RF of LPA (r = -0.51, p = 0.001); agreement between L% by NFV versus L% by PS was good (intraclass correlation coefficient [Ri] = 0.87) if RF of LPA <0.4 (n = 23) but downgraded (Ri = 0.51) and underestimated the L% (median of error = -14%, range = -25.3% to 5.5%) if RF of LPA > or =0.4 (n = 20). In contrast, agreement between L% by FFV versus L% by PS was high and unaffected by RF of LPA (Ri = 0.94, 0.92, respectively). While integrating PC-MRI of pulmonary artery as a comprehensive MRI evaluation of TOF after repair, conventional NFV ratio method tended to underestimate the left lung perfusion and may lead to unnecessary intervention. The FFV ratio method should be used for precise assessment of differential lung perfusion.

  3. Effect of halothane on metabolism of 5-hydroxytryptamine by rat lungs perfused in situ.

    PubMed Central

    Watkins, C A; Wartell, S A; Rannels, D E

    1983-01-01

    The effect of halothane (2-bromo-2-chloro-1,1,1-trifluoroethane) on the uptake of 14C-labelled 5-hydroxytryptamine (5-HT) and its metabolism to 5-hydroxyindol-3-ylacetic acid (5-HIAA) was investigated in rat lungs perfused in situ. The rate of accumulation of 14C-labelled 5-HIAA in the tissue, monitored as an index of 5-HT metabolism, was linear with time, displayed saturation kinetics and remained stable for at least 180 min of perfusion. Exposure of the lungs to halothane (4%) for 60 min reversibly reduced production of 5-HIAA through an increase in the apparent Km for metabolism of the amine from 1.45 to 3.52 microM (P less than 0.001); the anaesthetic had no effect on the Vmax. of the process. The magnitude of the inhibition increased with time of exposure to the anaesthetic. Halothane exposure did not alter the distribution of [3H]sorbitol or [14C]5-HT, pulmonary vascular resistance, levels of ATP or the kinetics of amino acid transport in the tissue. Inhibition of protein synthesis by cycloheximide did not mimic the effect of the anaesthetic. These observations, together with those made in lungs exposed to inhibitors of 5-HT uptake and metabolism, were consistent with a halothane-mediated inhibition of 5-HT uptake, which did not appear to involve non-specific changes in membrane permeability. PMID:6847641

  4. [Examination of R-L shunt ratio mensuration using dynamic images in lung perfusion scintigraphy].

    PubMed

    Ichikawa, Hajime; Yamada, Sayaka; Yoshioka, Chiho; Tamaoki, Toyoshi; Miura, Syunichi; Suzuki, Motoki; Makino, Tetsuzou

    2008-05-20

    We examined a method of quantitative analysis that used dynamic and static images to measure the Right-left (R-L) shunt ratio in lung perfusion scintigraphy. A total of 18 patients suspected of having R-L shunt brought on by congenital heart disease were referred for lung perfusion scintigraphy from November 2005 to February 2007 at our hospital. We acquired anterior dynamic images, set ROIs in all fields of view, and measured the highest count. We acquired anterior and posterior static images of the chest and measured lung counts. We considered the highest count on dynamic images to be the total injection dose per one second, normalized the acquisition time of static images, and calculated the R-L shunt ratio. We weighed the measurement results of the R-L shunt ratio obtained by the dynamic method against that of the whole-body method by t-test and the least-squares method. When we used a posterior static image in the dynamic method, we found that the coefficient of correlation (r) was 0.9831. The result of the t-test was that there was no significant difference at a level of significance of 1%. We think the use of the dynamic method is possible in R-L shunt ratio measurement and can shorten the examination time.

  5. The effects of hydrogen gas inhalation during ex vivo lung perfusion on donor lungs obtained after cardiac death.

    PubMed

    Haam, Seokjin; Lee, Sungsoo; Paik, Hyo Chae; Park, Moo Suk; Song, Joo Han; Lim, Beom Jin; Nakao, Atsunori

    2015-10-01

    Lung transplantation is a well-established treatment of end-stage lung disease; however, it is limited by a shortage of donor lungs. To overcome this problem, donation after cardiac death (DCD) and ex vivo lung perfusion (EVLP) are being widely investigated. In this study, the effect of hydrogen gas, a known antioxidant, was investigated on a DCD lung model during EVLP. Ten pigs were randomized into either a control (n = 5) or a hydrogen group (n = 5). After fibrillation by electric shock, no further treatment was administered in order to induce warm ischaemic injury for 1 h. The lungs were then procured, followed by 4 h of EVLP. During EVLP, the lungs were ventilated with room air in the control group, and with 2% hydrogen gas in the hydrogen group. Oxygen capacity (OC), pulmonary vascular resistance (PVR) and peak airway pressure (PAP) were measured every hour, and the expressions of interleukin-1 beta (IL-1β), IL-6 (IL-6), IL-8 (IL-8) and tumour necrosis factor-alpha (TNF-α) were evaluated in lung tissue after EVLP. Pathological evaluations were performed using lung injury severity (LIS) scores and the wet/dry ratio was also measured. The OC in the hydrogen group was higher than in the control group, but the difference was not statistically significant (P = 0.0862). PVR (P = 0.0111) and PAP (P = 0.0189) were statistically significantly lower in the hydrogen group. Compared with the control group, the hydrogen group had a statistically significantly lower expression of IL-1β (P = 0.0317), IL-6 (P = 0.0159), IL-8 (P = 0.0195) and TNF-α (P = 0.0159). The LIS scores (P = 0.0358) and wet/dry ratios (P = 0.040) were also significantly lower in the hydrogen group. Hydrogen gas inhalation during EVLP improved the function of DCD lungs, which may increase the utilization of DCD lungs. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  6. Donation After Circulatory Death Lungs Transplantable Up to Six Hours After Ex Vivo Lung Perfusion.

    PubMed

    Charles, Eric J; Huerter, Mary E; Wagner, Cynthia E; Sharma, Ashish K; Zhao, Yunge; Stoler, Mark H; Mehaffey, J Hunter; Isbell, James M; Lau, Christine L; Tribble, Curtis G; Laubach, Victor E; Kron, Irving L

    2016-12-01

    Despite the critical need for donor lungs, logistic and geographic barriers hinder lung utilization. We hypothesized that lungs donated after circulatory death subjected to 6 hours of cold preservation after ex vivo lung perfusion (EVLP) would have similar outcomes after transplantation as lungs transplanted immediately after EVLP, and that both would perform superiorly compared with lungs transplanted immediately after procurement. Donor porcine lungs were procured after circulatory death and 15 minutes of warm ischemia. Three groups (n = 5 per group) were randomized: immediate left lung transplantation (Immediate group), EVLP for 4 hours followed by transplantation (EVLP group), or EVLP for 4 hours followed by 6 hours of cold preservation followed by transplantation (EVLP+Cold group). Lungs were reperfused for 2 hours before obtaining pulmonary vein samples for partial pressure of oxygen/fraction of inspired oxygen ratio calculations, airway pressures for compliance measurements, and wet/dry weight ratios. The partial pressure of oxygen/fraction of inspired oxygen ratios in the EVLP and EVLP+Cold groups were significantly improved compared with those in the Immediate group (429.7 ± 51.8 and 436.7 ± 48.2 versus 117.4 ± 22.9 mm Hg, respectively). In addition, dynamic compliance was significantly improved in the EVLP and EVLP+Cold groups compared with immediate group (26.2 ± 4.2 and 27.9 ± 3.5 versus 11.1 ± 2.4 mL/cmH2O, respectively). There were no differences in oxygenation capacity or dynamic compliance between the EVLP and EVLP+Cold groups. Inflammatory cytokine levels were significantly lower in the EVLP and EVLP+Cold groups. Lungs donated after circulatory death can be successfully transplanted as much as 6 hours after EVLP. Cold preservation of lungs after ex vivo assessment and rehabilitation may improve organ allocation, even to distant recipients, without compromising allograft function. Copyright © 2016 The Society of Thoracic Surgeons

  7. 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.

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

    PubMed

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

    2007-03-07

    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.

  9. Liquid flow across the epithelium of the artificially perfused lung of fetal and postnatal sheep.

    PubMed Central

    Ramsden, C A; Markiewicz, M; Walters, D V; Gabella, G; Parker, K A; Barker, P M; Neil, H L

    1992-01-01

    1. The lungs of five fetal (133-140 days gestation) and thirty-four postnatal (2-240 days) sheep were artificially perfused in situ with warmed and oxygenated sheep blood. In postnatal animals the airspace of the lung was filled with liquid similar in composition to fetal lung liquid. In fetal and postnatal animals luminal liquid volume was measured by the impermeant tracer technique. 2. Under resting conditions the pulmonary epithelium of fetal animals secreted liquid at a mean (+/- S.E.M.) rate of 2.0 (+/- 0.4) ml (kg body weight)-1 h-1, those of postnantal animals absorbed liquid at -1.8 (+/- 0.2) ml (kg body weight)-1 h-1. 3. Addition of 2,4-dinitrophenol to achieve a concentration of 1.5 x 10(-3) M in the perfusing blood in postnatal animals caused complete cessation of liquid absorption. 4. Light and electron microscopic examination of the lung after periods of up to 6 h of artificial perfusion showed no evidence of epithelial damage. From 3 h onwards, liquid accumulation was evident in the perivascular spaces. 5. Addition of adrenaline to the perfusate in fetal animals caused absorption of liquid to occur at a mean rate of -2.9 (+/- 1.3) ml (kg body weight)-1 h-1. In postnatal animals adrenaline caused the rate of liquid absorption to increase from a mean rate of -1.4 (+/- 0.2) to -2.2 (+/- 0.3) ml (kg body weight)-1 h-1. 6. In the fetus addition of amiloride (0.8 x 10(-4) M) to the luminal fluid blocked adrenaline-induced liquid absorption and caused secretion to occur at 1.3 (+/- 0.3) ml (kg body weight)-1 h-1. 7. In postnatal animals the response to amiloride was age dependent. In newborn lambs (2-14 days) amiloride blocked liquid absorption and caused secretion of liquid to occur in seven out of eight animals at a mean rate of 0.9 (+/- 0.3) ml (kg body weight)-1 h-1 (n = 8). In older animals (15-240 days) the characteristic response to amiloride was slowing of the rate of liquid absorption (mean rate of absorption,-0.2 (+/- 0.09) ml (kg body weight)-1 h

  10. Real-time in-vivo imaging of pulmonary capillary perfusion using probe-based confocal laser scanning endomicroscopy in pigs: An interventional laboratory study.

    PubMed

    Gruber, Sybille; Spielauer, Isabella; Böhme, Stefan; Baron, David; Markstaller, Klaus; Ullrich, Roman; Klein, Klaus Ulrich

    2015-06-01

    Little is known about real-time in-vivo microscopy of pulmonary capillary perfusion because current microscopy requires direct access to lung tissue with surgical intervention such as the thoracic-window technique and open-lung model. To evaluate if probe-based confocal laser scanning endomicroscopy (pCLE) via the trachea allows for real-time in-vivo visualisation of pulmonary capillary density and red blood cell (RBC) velocity in pigs. An interventional animal study. European University Hospital. Nine female domestic pigs (50 to 60 kg) were used. A pCLE probe was positioned in non-dependent, central and dependent lung zones in nine anaesthetised pigs (Alveoflex, Cellvizio, Maunakea, France). After intravenous administration of fluorescein isothiocyanate dextran as contrast agent repetitive pCLE videos were recorded during pressure-controlled ventilation (PCV) or continuous positive airway pressure for 3 min each. Using fluorescein isothiocyanate-labelled RBC erythrocyte velocities in pulmonary capillaries were quantified. Data are expressed as mean ± SD or median with interquartile range (IQR). Capillary density was greater in dependent and central as compared with non-dependent lung zones [[32 (29 to 34) %] and 32 (30 to 34) % vs. 28 (26 to 28) %, respectively, P < 0.05]. During PCV, RBC velocities were higher in larger lung capillaries [diameter >20 μm, 309 μm s(-1) (209 to 397)] than intermediate [diameter 10.1 to 20 μm, 146 μm s(-1) (118 to 235)] and small [diameter <10 μm, 153 μm s(-1) (117 to 236), P <  .05]. During continuous positive airway pressure of 1.5 kPa, RBC velocities in dependent lung areas decreased to 47 μm s(-1) (30 to 82) compared with 198 μm s(-1) (148 to 290) during PCV (P < 0.05). pCLE allows endoscopic real-time in-vivo imaging of pulmonary capillary morphology and perfusion. Alterations in pulmonary capillary blood flow induced by different ventilator regimens can be detected. This minimally invasive approach via the

  11. 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

  12. Comparative imaging of differential pulmonary blood flow in patients with congenital heart disease: magnetic resonance imaging versus lung perfusion scintigraphy.

    PubMed

    Roman, Kevin S; Kellenberger, Christian J; Farooq, Saqba; MacGowan, Christopher K; Gilday, David L; Yoo, Shi-Joon

    2005-03-01

    Lung perfusion scintigraphy is considered the gold standard to assess differential pulmonary blood flow while magnetic resonance (MR) has been shown to be an accurate alternative in some studies. The purpose of the study was to assess the accuracy of phase contrast magnetic resonance (PC-MR) in measuring pulmonary blood flow ratio compared with lung perfusion scintigraphy in patients with complex pulmonary artery anatomy or pulmonary hypertension and to document reasons for discrepant results. We identified 25 cases of congenital heart disease between January 2000 and 2003, in whom both techniques of assessing pulmonary blood flow were performed within a 6-month period without an interim surgical or transcatheter intervention. The study group included cases with branch pulmonary artery stenosis, intracardiac shunts, single ventricle circulation, pulmonary venous anomalies and conotruncal defects. The mean age at study was 5.7 years (range 0.33-12) with a mean weight of 20.3 kg (range 6.5-53.6). The two methods were compared using a Bland-Altman analysis, and the Pearson correlation coefficient was calculated using the lung scan as the gold standard. Discrepant results were examined by reviewing the source images to elucidate reasons for error by MR. Bland-Altman analysis comparing right pulmonary artery (RPA) blood flow percentage, as measured by each modality, showed a mean difference of 1.43+/-9.8 (95% limits of agreement: -17.8, 20.6) with a correlation coefficient of r=0.84, P<0.0001. In six (24%) cases a large difference (>10%) was found with a mean difference between techniques of 17.9%. The reasons for discrepant results included MR artifacts, dephasing owing to turbulent flow, site of data acquisition and lobar lung collapse. When using PC-MR to assess pulmonary blood flow ratio, important technical errors occur in a significant proportion of patients who have abnormal pulmonary artery anatomy or pulmonary hypertension. If these technical errors are avoided

  13. 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).

  14. 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

  15. Normothermic Ex Vivo Lung Perfusion in Brain-dead Donors Reduces Inflammatory Cytokines and Toll-like Receptor Expression.

    PubMed

    Shafaghi, Shadi; Mortaz, Esmaeil; Abbasi Dezfuli, Azizollah; Godarzi, Hoda; Sheikhy, Kambiz; Ansari Aval, Zahra; Farzanegan, Behrooz; Emami, Habib; Hosseini-Baharanchi, Fatemeh Sadat; Najafizadeh, Katayoun

    2016-10-01

    Inflammatory responses and innate immunologic reactions play an important role in the respiratory system. Ex vivo lung perfusion (EVLP) is considered a novel method in the evaluation and reconditioning of donor lungs prior to transplantation. However, EVLP's effect on inflammatory and metabolic markers of human lung tissue is unknown.  This study investigated how the performance of EVLP on brain-dead (BD) donor lungs affects the production and release of inflammatory cytokines (IL-6, IL-8, and TNF-a), inflammatory cells and toll-like receptors (TLR) -2, 4. This study was conducted with an animal subject for qualification of EVLP team and then EVLP was performed on 4 human cases referred to Masih Daneshvari Hospital (Tehran,Iran), from May 2013 to July 2015. Two of these cases, who had acceptable lung function parameters, were enrolled in this study for immunologic investigations. Bronchoalveolar lavages (BAL) were taken before and after EVLP. Cytokines were quantitatively measured before lung retrieval, at the end of the lung removal, at the start of EVLP, and at the end of the each hour of EVLP. TLR expression was measured on the cells obtained by flow cytometry. TNF-a, IL-6 and IL-8 decreased in each stage of washing perfusate in both cases, and the level of cytokines in serum was in the normal range. Flow cytometry analysis revealed a decreasing expression of CD3, CD4/8, CD19, and CD16+56, as well as TLR-2 and TLR-4 in both cases. Intra-capillary pools of pro-inflammatory cytokines (IL-6, IL-8, and TNF-a) were determined to contribute to the lung injury during prolonged lung perfusion. This raises the possibility that EVLP donor lungs could be less immunogenic than standard lungs. However, to assess EVLP's effects on lung grafts and optimize recipient outcomes, further studies with a sufficient number of lungs are required.

  16. Measurement of ventilation- and perfusion-mediated cooling during laser ablation in ex vivo human lung tumors.

    PubMed

    Vietze, Andrea; Koch, Franziska; Laskowski, Ulrich; Linder, Albert; Hosten, Norbert

    2011-11-01

    Perfusion-mediated tissue cooling has often been described in the literature for thermal ablation therapies of liver tumors. The objective of this study was to investigate the cooling effects of both perfusion and ventilation during laser ablation of lung malignancies. An ex vivo lung model was used to maintain near physiological conditions for the specimens. Fourteen human lung lobes containing only primary lung tumors (non-small cell lung cancer) were used. Laser ablation was carried out using a Nd:YAG laser with a wavelength of 1064 nm and laser fibers with 30 mm diffusing tips. Continuous invasive temperature measurement in 10 mm distance from the laser fiber was performed. Laser power was increased at 2 W increments starting at 10 W up to a maximum power of 12-20 W until a temperature plateau around 60 °C was reached at one sensor. Ventilation and perfusion were discontinued for 6 min each to assess their effects on temperature development. The experiments lead to 25 usable temperature profiles. A significant temperature increase was observed for both discontinued ventilation and perfusion. In 6 min without perfusion, the temperature rose about 5.5 °C (mean value, P<0.05); without ventilation it increased about 7.0 °C (mean value, P<0.05). Ventilation- and perfusion-mediated tissue cooling are significant influencing factors on temperature development during thermal ablation. They should be taken into account during the planning and preparation of minimally invasive lung tumor treatment in order to achieve complete ablation. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  17. Ex Vivo Perfusion With Adenosine A2A Receptor Agonist Enhances Rehabilitation of Murine Donor Lungs After Circulatory Death.

    PubMed

    Stone, Matthew L; Sharma, Ashish K; Mas, Valeria R; Gehrau, Ricardo C; Mulloy, Daniel P; Zhao, Yunge; Lau, Christine L; Kron, Irving L; Huerter, Mary E; Laubach, Victor E

    2015-12-01

    Ex vivo lung perfusion (EVLP) enables assessment and rehabilitation of marginal donor lungs before transplantation. We previously demonstrated that adenosine A2A receptor (A2AR) agonism attenuates lung ischemia-reperfusion injury. The current study utilizes a novel murine EVLP model to test the hypothesis that A2AR agonist enhances EVLP-mediated rehabilitation of donation after circulatory death (DCD) lungs. Mice underwent euthanasia and 60 minutes warm ischemia, and lungs were flushed with Perfadex and underwent cold static preservation (CSP, 60 minutes). Three groups were studied: no EVLP (CSP), EVLP with Steen solution for 60 minutes (EVLP), and EVLP with Steen solution supplemented with ATL1223, a selective A2AR agonist (EVLP + ATL1223). Lung function, wet/dry weight, cytokines and neutrophil numbers were measured. Microarrays were performed using the Affymetrix GeneChip Mouse Genome 430A 2.0 Array. Ex vivo lung perfusion significantly improved lung function versus CSP, which was further, significantly improved by EVLP + ATL1223. Lung edema, cytokines, and neutrophil counts were reduced after EVLP and further, significantly reduced after EVLP + ATL1223. Gene array analysis revealed differential expression of 1594 genes after EVLP, which comprise canonical pathways involved in inflammation and innate immunity including IL-1, IL-8, IL-6, and IL-17 signaling. Several pathways were uniquely regulated by EVLP + ATL1223 including the downregulation of genes involved in IL-1 signaling, such as ADCY9, ECSIT, IRAK1, MAPK12, and TOLLIP. Ex vivo lung perfusion modulates proinflammatory genes and reduces pulmonary dysfunction, edema, and inflammation in DCD lungs, which are further reduced by A2AR agonism. This murine EVLP model provides a novel platform to study rehabilitative mechanisms of DCD lungs.

  18. 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.

  19. /sup 67/Gallium lung scans in progressive systemic sclerosis

    SciTech Connect

    Baron, M.; Feiglin, D.; Hyland, R.; Urowitz, M.B.; Shiff, B.

    1983-08-01

    /sup 67/Gallium lung scans were performed in 19 patients with progressive systemic sclerosis (scleroderma). Results were expressed quantitatively as the /sup 67/Gallium Uptake Index. The mean total pulmonary /sup 67/Gallium Uptake Index in patients was significantly higher than that in controls (41 versus 25), and 4 patients (21%) fell outside the normal range. There were no clinical or laboratory variables that correlated with the /sup 56/Gallium uptake. Increased pulmonary /sup 67/Gallium uptake in scleroderma may prove useful as an index of pulmonary disease activity.

  20. 67Gallium lung scans in progressive systemic sclerosis.

    PubMed

    Baron, M; Feiglin, D; Hyland, R; Urowitz, M B; Shiff, B

    1983-08-01

    67Gallium lung scans were performed in 19 patients with progressive systemic sclerosis (scleroderma). Results were expressed quantitatively as the 67Gallium Uptake Index. The mean total pulmonary 67Gallium Uptake Index in patients was significantly higher than that in controls (41 versus 25), and 4 patients (21%) fell outside the normal range. There were no clinical or laboratory variables that correlated with the 56gallium uptake. Increased pulmonary 67gallium uptake in scleroderma may prove useful as an index of pulmonary disease activity.

  1. Diagnosis of pulmonary embolus using ventilation/perfusion lung scintigraphy: more than 0.5 segment of ventilation/perfusion mismatch is sufficient.

    PubMed

    Howarth, D M; Booker, J A; Voutnis, D D

    2006-05-01

    To determine the optimal diagnostic cut-off point using a simplified criterion for the detection of pulmonary embolus (PE) and to evaluate the criterion's utility and reporter reproducibility. Lung scintigraphy was carried out in 924 patients for the diagnosis of PE. This group consisted of 316 men and 608 women with median age of 63 years (range 18-94 years). Ventilation imaging was carried out with Tc-99m Technegas followed by perfusion imaging using 190 MBq Tc-99m macroaggregated albumin. Studies were classified using a 6-category probability criterion of incremental ventilation/perfusion (V/Q) mismatch: A, normal; B, low (minor matched V/Q defects or segmental matched V/Q defects without opacity on chest X-ray); C, low-moderate (a partial segment of V/Q mismatch); D, moderate (1 segment of mismatch); E, moderate-high (1-2 segments of V/Q mismatch) and F, high probability (=2 segments of V/Q mismatch). Clinical end-points at 3 and 6 months were death by PE or PE treated with anticoagulation therapy. Three-reporter reproducibility was determined by kappa statistic on a subgroup of patients (53/924). A total of 122 patients (13%) had a confirmed diagnosis of PE at 3 months and no additional cases were registered at 6 months. The lung scintigraphy probability classification showed: normal 152 (16%), low 620 (67%), low-moderate 20 (2%), moderate 28 (3%), moderate-high 24 (3%) and high 80 (9%). The respective sensitivities and specificities, where the diagnostic cut-offs were established at F, high; E, moderate-high; D, moderate and C, low-moderate probability, were F, 64 and 100%; E, 82 and 99%; D, 95 and 98% and C, 98 and 96%. The respective false-negative cases for F, E, D and C cut-offs were 44, 22, 7 and 3. Using the revised Prospective Investigation of Pulmonary Embolism Diagnosis reporting classification reporter agreement showed kappa values of 0.31-0.48. Using a simplified 2-category (>0.5 segment of V/Q mismatch positive, all others negative) criterion

  2. 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

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

    PubMed

    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

    2011-07-07

    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

  4. Multispectral single-scan lung imaging system: initial feasibility

    NASA Astrophysics Data System (ADS)

    Besson, Guy M.; Crocker, Kenneth E.

    2006-03-01

    This paper describes a system for multi-spectral single-scan lung imaging. The proposed approach relies on a low noise detector sampled at a high rate. The proposed method overcomes limitations of CCD time-and-delay integration slot-scanning systems. The system design and preliminary specifications are described. The results of initial spectral and system simulations in support of system feasibility per the outlined specifications are described. Initial investigations support the potential of the proposed approach to alleviate four shortcomings of the current digital flat-panel approach to chest radiography: (i) by enabling dynamic multi-spectral imaging in a single scan, the approach reduces the time delay between exposures, thus reducing sensitivity to motion; (ii) the approach enables dynamic technique feedback and technique adaptation, eliminating the need for a pre-exposures and reducing the likelihood of poor x-ray techniques in local image areas; (iii) by enabling direct measurement of the scatter field, the proposed method allows further scatter correction resulting in image quality improvements; (iv) finally, full-frame sampling of a digital detector allows imaging of the beam penumbra, thereby reclaiming the detection quantum efficiency loss due to over-collimation in current TDI slot-scanning approach; the resulting DQE potentially exceeds that of flat-panel detectors by a factor up to two.

  5. Scanning electron microscopy of lung following alpha irradiation

    SciTech Connect

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

    1989-09-01

    Pulmonary aggregation of inhaled {sup 239}PuO{sub 2} particles leads to a cellular evolution of focal inflammation, fibrosis, epithelial dysplasia and lung tumor formation. Female Wistar rats were exposed to an aerosol of high-fired {sup 239}PuO{sub 2} (initial lung burden, 3.9 kBq) and the lungs examined at intervals from 1 day to 700 days after exposure by light and scanning electron microscopy and autoradiography. Peribronchiolar Pu particle aggregation increased with time, resulting in well-defined focal inflammatory lesions after 120 days and fibrotic lesions after 180 days. A generalized hypertrophy and hyperplasia of nonciliated bronchiolar cells was seen at 15 days and type II cell hyperplasia by 30 days after exposure. Focal dysplastic changes in type II alveolar epithelium and terminal nonciliated bronchiolar epithelium preceded carcinoma formation. Alveolar bronchiolarization was first noted at 120 days, squamous metaplasia at 210 days, squamous carcinoma at 270 days and adenocarcinoma at 600 days after exposure.

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

    PubMed

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

    2017-10-10

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

  7. Pharmacological Reconditioning of Marginal Donor Rat Lungs Using Inhibitors of Peroxynitrite and Poly (ADP-ribose) Polymerase During Ex Vivo Lung Perfusion.

    PubMed

    Wang, Xingyu; Wang, Yabo; Parapanov, Roumen; Abdelnour, Etienne; Gronchi, Fabrizio; Perentes, Jean Yannis; Piquilloud, Lise; Ris, Hans-Beat; Letovanec, Igor; Liaudet, Lucas; Krueger, Thorsten

    2016-07-01

    Donor lungs obtained after prolonged warm ischemia (WI) may be unsuitable for transplantation due to the risk of reperfusion injury, but could be reconditioned using ex-vivo lung perfusion (EVLP). Key processes of reperfusion injury include the formation of reactive oxygen species (ROS)/nitrogen species (RNS) and the activation of poly(adenosine diphosphate-ribose) polymerase (PARP). We explored whether rat lungs obtained after WI could be reconditioned during EVLP using the ROS/RNS scavenger Mn(III)-tetrakis (4-benzoic acid) porphyrin chloride (MnTBAP) or the PARP inhibitor 3-aminobenzamide (3-AB). Rat lungs obtained after 3 hours cold ischemia (CI group, control), or 1 hour WI plus 2 hours CI (WI group) were placed in an EVLP circuit for normothermic perfusion for 3 hours. Lungs retrieved after WI were treated or not with 3-AB (1 mg/mL) or MnTBAP (0.3 mg/mL), added to the perfusate. Measurements included physiological variables (lung compliance, vascular resistance, oxygenation capacity), lung weight gain, levels of proteins, lactate dehydrogenase, protein carbonyl (marker of ROS), 3-nitrotyrosine (marker of RNS), poly(adenosine diphosphate-ribose) (PAR, marker of PARP activation) and IL-6, in the bronchoalveolar lavage or the lung tissue, and histology. In comparison to the CI group, the lungs from the WI group displayed higher protein carbonyls, 3-nitrotyrosine, PAR, lactate dehydrogenase and proteins in bronchoalveolar lavage, lung weight gain, perivascular edema, as well as reduced static compliance, but similar oxygenation. All these alterations were markedly attenuated by 3-AB and MnTBAP. After EVLP, lungs obtained after WI exhibit oxidative stress, PARP activation, and tissue injury, which are suppressed by pharmacological inhibitors of ROS/RNS and PARP.

  8. Lung [(18)F]fluorodeoxyglucose uptake and ventilation-perfusion mismatch in the early stage of experimental acute smoke inhalation.

    PubMed

    Musch, Guido; Winkler, Tilo; Harris, R Scott; Vidal Melo, Marcos F; Wellman, Tyler J; de Prost, Nicolas; Kradin, Richard L; Venegas, Jose G

    2014-03-01

    Acute lung injury occurs in a third of patients with smoke inhalation injury. Its clinical manifestations usually do not appear until 48-72 h after inhalation. Identifying inflammatory changes that occur in pulmonary parenchyma earlier than that could provide insight into the pathogenesis of smoke-induced acute lung injury. Furthermore, noninvasive measurement of such changes might lead to earlier diagnosis and treatment. Because glucose is the main source of energy for pulmonary inflammatory cells, the authors hypothesized that its pulmonary metabolism is increased shortly after smoke inhalation, when classic manifestations of acute lung injury are not yet expected. In five sheep, the authors induced unilateral injury with 48 breaths of cotton smoke while the contralateral lung served as control. The authors used positron emission tomography with: (1) [F]fluorodeoxyglucose to measure metabolic activity of pulmonary inflammatory cells; and (2) [N]nitrogen in saline to measure shunt and ventilation-perfusion distributions separately in the smoke-exposed and control lungs. The pulmonary [F]fluorodeoxyglucose uptake rate was increased at 4 h after smoke inhalation (mean ± SD: 0.0031 ± 0.0013 vs. 0.0026 ± 0.0010 min; P < 0.05) mainly as a result of increased glucose phosphorylation. At this stage, there was no worsening in lung aeration or shunt. However, there was a shift of perfusion toward units with lower ventilation-to-perfusion ratio (mean ratio ± SD: 0.82 ± 0.10 vs. 1.12 ± 0.02; P < 0.05) and increased heterogeneity of the ventilation-perfusion distribution (mean ± SD: 0.21 ± 0.07 vs. 0.13 ± 0.01; P < 0 .05). Using noninvasive imaging, the authors demonstrated that increased pulmonary [F]fluorodeoxyglucose uptake and ventilation-perfusion mismatch occur early after smoke inhalation.

  9. Isolated Lung Perfusion as an Adjuvant Treatment of Colorectal Cancer Lung Metastases: A Preclinical Study in a Pig Model

    PubMed Central

    Pagès, Pierre-Benoit; Facy, Olivier; Mordant, Pierre; Ladoire, Sylvain; Magnin, Guy; Lokiec, Francois; Ghiringhelli, Francois; Bernard, Alain

    2013-01-01

    Background The lung is a frequent site of colorectal cancer (CRC) metastases. After surgical resection, lung metastases recurrences have been related to the presence of micrometastases, potentially accessible to a high dose chemotherapy administered via adjuvant isolated lung perfusion (ILP). We sought to determine in vitro the most efficient drug when administered to CRC cell lines during a short exposure and in vivo its immediate and delayed tolerance when administered via ILP. Methods First, efficacy of various cytotoxic molecules against a panel of human CRC cell lines was tested in vitro using cytotoxic assay after a 30-minute exposure. Then, early (operative) and delayed (1 month) tolerance of two concentrations of the molecule administered via ILP was tested on 19 adult pigs using hemodynamic, biological and histological criteria. Results In vitro, gemcitabine (GEM) was the most efficient drug against selected CRC cell lines. In vivo, GEM was administered via ILP at regular (20 µg/ml) or high (100 µg/ml) concentrations. GEM administration was associated with transient and dose-dependant pulmonary vasoconstriction, leading to a voluntary decrease in pump inflow in order to maintain a stable pulmonary artery pressure. After this modulation, ILP using GEM was not associated with any systemic leak, systemic damage, and acute or delayed histological pulmonary toxicity. Pharmacokinetics studies revealed dose-dependant uptake associated with heterogenous distribution of the molecule into the lung parenchyma, and persistent cytotoxicity of venous effluent. Conclusions GEM is effective against CRC cells even after a short exposure. ILP with GEM is a safe and reproducible technique. PMID:23527205

  10. Relationships between perfusion defects and static brain scan positivity in patients with ischaemic completed stroke: considerations about the origin of the increased uptake

    PubMed Central

    Bartolini, Alfredo

    1982-01-01

    The relation between perfusion defects shown by radionuclide angiography and static brain scan positivity was evaluated in patients with ischaemic completed stroke at various intervals from the onset of symptoms. An inverse relation between radionuclide angiography and static scan positivity was found for the period within 15 days of the onset of symptoms. The possible relation between changes in perfusion and static brain scan positivity is discussed. PMID:6279782

  11. The matching of ventilation and perfusion in the lung of the Tegu lizard, Tupinambis nigropunctatus.

    PubMed

    Hlastala, M P; Standaert, T A; Pierson, D J; Luchtel, D L

    1985-06-01

    Ventilation-perfusion (VA/Q) distribution was evaluated in the Tegu lizard, Tupinambis nigropunctatus, using the multiple inert gas elimination technique (MIGET) in order to define the limitations to gas exchange in the large chambered unicameral lung. The lizards (0.52-1.1 kg) were anesthetized with halothane and ventilated. Body temperature was maintained at 35 degrees C. Arterial and sinus venosus PO2 averaged 79.4 +/- 5.9 and 47.3 +/- 6.4 torr while breathing air and 232.1 +/- 31 and 64.8 +/- 11.5 torr while breathing oxygen. VA/Q distributions were broad and right-to-left shunt averaged 21% while breathing air and 27% while breathing oxygen. Gas exchange was significantly impaired due to the presence of both shunt and VA/Q heterogeneity. The walls of the lung enclose a large axial air chamber. Microscopic examination revealed approximately three generations of septa which subdivided the wall into tubular-shaped gas-exchange chambers. Wall thickness averages 2.8 mm at the anterior end of the lung, 2.1 mm in the middle portion of the lung and 1.4 mm at the posterior end. The thickness of the blood-air barrier (epithelial-basal lamina-endothelial cell layer) ranged from 0.35 to 0.90 micron. Although this barrier is slightly thicker than in the mammalian lung (0.1-0.5 micron), it is unlikely to be a source of diffusion limitation in gas exchange at rest.

  12. Automated lung volumetry from routine thoracic CT scans: how reliable is the result?

    PubMed

    Haas, Matthias; Hamm, Bernd; Niehues, Stefan M

    2014-05-01

    Today, lung volumes can be easily calculated from chest computed tomography (CT) scans. Modern postprocessing workstations allow automated volume measurement of data sets acquired. However, there are challenges in the use of lung volume as an indicator of pulmonary disease when it is obtained from routine CT. Intra-individual variation and methodologic aspects have to be considered. Our goal was to assess the reliability of volumetric measurements in routine CT lung scans. Forty adult cancer patients whose lungs were unaffected by the disease underwent routine chest CT scans in 3-month intervals, resulting in a total number of 302 chest CT scans. Lung volume was calculated by automatic volumetry software. On average of 7.2 CT scans were successfully evaluable per patient (range 2-15). Intra-individual changes were assessed. In the set of patients investigated, lung volume was approximately normally distributed, with a mean of 5283 cm(3) (standard deviation = 947 cm(3), skewness = -0.34, and curtosis = 0.16). Between different scans in one and the same patient the median intra-individual standard deviation in lung volume was 853 cm(3) (16% of the mean lung volume). Automatic lung segmentation of routine chest CT scans allows a technically stable estimation of lung volume. However, substantial intra-individual variations have to be considered. A median intra-individual deviation of 16% in lung volume between different routine scans was found. Copyright © 2014 AUR. Published by Elsevier Inc. All rights reserved.

  13. Incidence of a single subsegmental mismatched perfusion defect in single-photon emission computed tomography and planar ventilation/perfusion scans.

    PubMed

    Stubbs, Matthew; Chan, Kenneth; McMeekin, Helena; Navalkissoor, Shaunak; Wagner, Thomas

    2017-02-01

    This study aims to compare the incidence of ventilation/perfusion (V/Q) scans interpreted as indeterminate for the diagnosis of pulmonary embolism (PE) using single-photon emission computed tomography (SPECT) versus planar scintigraphy and to consider the effect of variable interpretation of single subsegmental V/Q mismatch (SSM). A total of 1300 consecutive V/Q scans were retrospectively reviewed. After exclusion and matching for age and sex, 542 SPECT and 589 planar scans were included in the analysis. European Association of Nuclear Medicine guidelines were used to interpret the V/Q scans, initially interpreting SSM as negative scans. Patients with SSM were followed up for 3 months and further imaging for PE was collected. Indeterminate scans were significantly fewer in the SPECT than the planar group on the basis of the initial report (7.7 vs. 12.2%, P<0.05). This is irrespective of classification of SSM as a negative scan (4.6 vs. 12.1%, P<0.0001) or an indeterminate scan (8.3 vs. 12.2%, P<0.05). Of the 21 patients who had SSM, 19 underwent computer tomography pulmonary angiogram and embolism was found in one patient. None of these patients died at the 3-month follow-up. V/Q SPECT has greater diagnostic certainty of PE, with a 41% reduction in an indeterminate scan compared with planar scintigraphy. This is irrespective of the clinician's interpretation of SSM as negative or intermediate probability. Patients with SSM would not require further computer tomography pulmonary angiogram imaging.

  14. Pulmonary effects and disposition of luteolin and Artemisia afra extracts in isolated perfused lungs.

    PubMed

    Joel Mjiqiza, Sizwe; Abraham Syce, James; Chibuzo Obikeze, Kenechukwu

    2013-10-07

    Artemisia afra (Asteraceae) is a traditional medicinal plant frequently used in steam inhalation form to treat respiratory conditions. Quantify luteolin content in Artemisia afra dried crude and aqueous extract. Evaluate the pulmonary effects of Artemisia afra steam inhalation, nebulized Artemisia afra extract and luteolin in isolated perfused lungs (IPL). Evaluate the pulmonary disposition of intravenously administered luteolin. HPLC was used to quantify luteolin in Artemisia afra extracts. A modified version of the IPL was used to determine the effects of Artemisia afra steam inhalation, nebulized luteolin, and nebulized aqueous leaf extract on lung function, as well as the pulmonary disposition of IV luteolin. Artemisia afra extract contained significantly higher luteolin levels than the crude dried leaves. Inhaled Artemisia afra steam, and nebulized luteolin, and Artemisia afra extract and IV luteolin produced significant dose-dependent improvements in lung function, with nebulized Artemisia afra producing the greatest improvements. Nebulisation with Artemisia afra extract yielded higher quantities of luteolin than luteolin nebulisation. Results verify the traditional use of inhalation of Artemisia afra steam, although nebulized luteolin and aqueous extract are better alternatives. Luteolin significantly contributes to the bronchodilatory effects of Artemisia afra. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  15. Utility of CT perfusion scanning in patient selection for acute stroke intervention: experience at University at Buffalo Neurosurgery-Millard Fillmore Gates Circle Hospital.

    PubMed

    Kan, Peter T; Snyder, Kenneth V; Yashar, Parham; Siddiqui, Adnan H; Hopkins, L Nelson; Levy, Elad I

    2011-06-01

    Computed tomography perfusion scanning generates physiological flow parameters of the brain parenchyma, allowing differentiation of ischemic penumbra and core infarct. Perfusion maps, along with the National Institutes of Health Stroke Scale score, are used as the bases for endovascular stroke intervention at the authors' institute, regardless of the time interval from stroke onset. With case examples, the authors illustrate their perfusion-based imaging guidelines in patient selection for endovascular treatment in the setting of acute stroke.

  16. Multislice Analysis of Blood Flow Values in CT Perfusion Studies of Lung Cancer

    PubMed Central

    Malavasi, Silvia; Barone, Domenico; Gavelli, Giampaolo

    2017-01-01

    Objectives. Tumour heterogeneity represents a key issue in CT perfusion (CTp), where all studies are usually based on global mean or median values of perfusion maps, often computed on whole tumour. We sought to determine whether, and to what extent, such global values can be representative of tumour heterogeneity, with respect to single slices, and could be used for therapy assessment. Materials and Methods. Twelve patients with one primary non-small cell lung cancer lesion were enrolled in this study, for a total amount of 26 CTp examinations and 118 slices. Mean and median blood flow (BF) values, calculated voxel-based, were computed on each slice and the whole tumour. To measure functional heterogeneity, entropy was calculated on BF values as well. Results. Most of the slices were not represented by the global BF values computed on the whole tumour. In addition, there are a number of lesions having equivalent global BF values, but they are composed of slices having very different heterogeneity distributions, that is, entropy values. Conclusions. Global mean/median BF values of the single slices separately should be considered for clinical assessment, only if interpreted through entropy computed on BF values. The numerical equivalence between global BF values of different lesions may correspond to different clinical status, thus inducing possible errors in choice of therapy when considering global values only. PMID:28164118

  17. 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.

  18. 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.

  19. [Radionuclide evaluation of lung perfusion after transcatheter closure of patent ductus arteriosus: analysis of frequently used two different types of coils].

    PubMed

    Polat, Tuğçin Bora; Celebi, Ahmet; Hacımahmutoğlu, Sevim; Akdeniz, Celal; Erdem, Abdullah; Fırat, Fatih

    2011-05-01

    Impaired left lung perfusion (LLP) has been described after transcatheter closure of the patent ductus arteriosus (PDA). In this study, we aimed to evaluate lung perfusion scans (LPSs) following occlusion of PDA with two frequently used coils: Cook detachable coil and Gianturco coil. A prospective study of 89 patients who underwent PDA occlusion using the Cook coils in 49 and the Gianturco coils in 40, was conducted. LPSs were performed after a median period of 18 months. The relationships between the LPSs and continuous variables were assessed by Pearson correlation analysis and the cut-off value of the best correlated parameters to predict abnormal LPSs obtained by the Receiver Operating Characteristic (ROC) analysis. Decreased left lung perfusion (LLP) was found in 13 patients including 10 after using Cook coils and 3 after using Gianturco coils (p=0.077). LLP values were significantly correlated with the loops deployed at the pulmonary side, coil/ductal diameter ratio and number of coils deployed (p=0.002, p=0.006 and p=0.009, respectively). Number of loops deployed at the pulmonary side >1.4 (specificity 77%, sensitivity 85%, area under the ROC curve 0.804, 95%CI 0.661-0.947, p<0.001) and first coil/ductal diameter ratio >1.85 (specificity 70%, sensitivity 77%, area under the ROC curve 0.747, 95%CI 0.423-0.790, p<0.005) were the best discriminative cut-off values of decreased LLP. Impaired LLP may appear following transcatheter closure of PDA with either Cook detachable coils or Gianturco coils. This situation may be complicated with loops deployed at the pulmonary side, the use of relatively large size of coil with respect to the ductal diameter and the use of multiple coils.

  20. Mechanical factors and the regulation of perfusion through atelectatic lung in pigs.

    PubMed

    Enjeti, S; Terry, P B; Menkes, H A; Traystman, R J

    1982-03-01

    The role of mechanical interdependence in the perfusion of atelectatic lung was studied in two ways: a) regional hemodynamics were compared before (control) and after the development of lobar and sublobar atelectasis, and b) the effect of thoracotomy on regional hemodynamics was assessed. With lobar atelectasis mean lobar blood flow and vascular conductance decreased to 60% of control. Sublobar atelectasis caused mean sublobar blood flow and vascular conductance to decrease to 6% of control. Opening the chest after production of lobar atelectasis caused blood flow to fall to 50% of control. When sublobar atelectasis was produced in the open chest, sublobar blood flow decreased to 25% of control measurements made prior to thoracotomy. We conclude that with a closed chest, sublobar vascular distortion mediated by mechanical interdependence may be an important mechanism responsible for the differences in hemodynamic responses to atelectasis between lobes and sublobar regions.

  1. 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

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

    PubMed

    Goo, Hyun Woo; Park, Sang Hyub

    2017-06-23

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

  3. Evaluation of mosaic pattern areas in HRCT with Min-IP reconstructions in patients with pulmonary hypertension: could this evaluation replace lung perfusion scintigraphy?

    PubMed

    Rossi, A; Attinà, D; Borgonovi, A; Buia, F; De Luca, F; Guidalotti, P L; Fughelli, P; Galiè, N; Zompatori, M

    2012-01-01

    defects) and homogeneous in LPS, in 5 cases inhomogeneous (1 with non-segmental patchy defects, 4 with segmental defects) in LPS images and homogeneous in Min-IP. In a general view, Min-IP reconstruction without contrast-medium showed a sensitivity of 100% and specificity of 96.1%, positive predictive value (PPV) of 92.3% and negative predictive value (NPV) of 100%, to recognize a pattern of lung attenuation inhomogeneous with segmental defects correspondent to a chronic thromboembolic condition, no false negative cases and three false positive cases; on the other hand LPS, on its own, showed a sensitivity of 91.67% and specificity of 93.51%, positive predictive value (PPV) of 86.84% and negative predictive value (NPV) of 96%, 3 false negative cases and 5 false positive cases. Min-IP obtained in HRCT without contrast-medium and in CTPA were equivalent. Min-IP images generally showed a higher sensitivity and specificity than LPS in the evaluation of lung perfusion regarding patients with pulmonary hypertension caused by different etiology, particularly in CTEPH patients. These results can be completed with the evaluation of HRCT and CTPA basal scans, providing more informations than ventilation/perfusion lung scintigraphy. HRCT images integrated by Min-IP reconstruction can represent the first step in the diagnostic algorithm of patients affected by dyspnoea and pulmonary hypertension of unknown causes, reserving the use of contrast-medium only in selected patients and reducing the patients' X-ray-exposition. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  4. 99mTc technegas ventilation and perfusion lung scintigraphy for the diagnosis of pulmonary embolus.

    PubMed

    Howarth, D M; Lan, L; Thomas, P A; Allen, L W

    1999-04-01

    Lung scintigraphy is used widely for diagnosis of pulmonary embolus (PE). Technegas ventilation imaging has many advantages over other methods, but little outcome data exists on this technique. The aims of this study were to better define the role of lung scintigraphy in the management of patients with suspected PE and to evaluate technegas ventilation imaging by following patient outcomes. A group of 717 out of 834 consecutive patients, referred to a university teaching hospital for lung scintigraphy to confirm or refute the diagnosis of PE, was followed for 18-30 mo to determine clinical outcome. The follow-up endpoints were death as a result of PE, death as a result of hemorrhage after treatment for PE, uncomplicated survival, survival with subsequent PE, nonfatal hemorrhage after treatment for PE and recurrence of PE in treated patients. Ventilation imaging was performed using technegas, and perfusion imaging was performed using intravenous 99mTc macroaggregated albumin. The modified PIOPED (Prospective Investigation of Pulmonary Embolism Diagnosis) diagnostic criterion was used for interpretation of lung scintigraphy. Diagnostic results included 3.5% normal studies, 67.4% assessed as low probability for PE, 10% as moderate probability for PE and 19.1% as high probability for PE. A total of 231 patents received therapy with heparin, followed by warfarin, including those receiving anticoagulation therapy for other conditions. Ninety-six percent of patients with normal and low probability studies (n = 508) had good outcomes, 6 patients died as a result of PE and 12 subsequently developed PE. The odds ratio for death by PE in this group was 0.2. Of the 72 moderate probability studies, 39 patients were untreated. In this group there was 1 death due to PE, and PE subsequently developed in 2 patients. None of the remaining 33 treated patients died, but 4 patients experienced bleeding complications. The odds ratio for death by PE in the moderate probability group was

  5. Lung [18F]fluorodeoxyglucose uptake and ventilation-perfusion mismatch in the early stage of experimental acute smoke inhalation

    PubMed Central

    Musch, Guido; Winkler, Tilo; Harris, R. Scott; Vidal Melo, Marcos F.; Wellman, Tyler J.; de Prost, Nicolas; Kradin, Richard L.; Venegas, Jose G.

    2014-01-01

    Background Acute lung injury (ALI) occurs in a third of patients with smoke inhalation injury. Its clinical manifestations usually do not appear until 48 to 72 h after inhalation. Identifying inflammatory changes that occur in pulmonary parenchyma earlier than that could provide insight into the pathogenesis of smoke-induced ALI. Furthermore, noninvasive measurement of such changes might lead to earlier diagnosis and treatment. Because glucose is the main source of energy for pulmonary inflammatory cells, we hypothesized that its pulmonary metabolism is increased shortly after smoke inhalation, when classic manifestations of ALI are not yet expected. Methods In five sheep we induced unilateral injury with 48 breaths of cotton smoke while the contralateral lung served as control. We used positron emission tomography with: 1) [18F]fluorodeoxyglucose to measure pulmonary inflammatory cell metabolic activity; and 2) [13N]nitrogen in saline to measure shunt and ventilation-perfusion distributions separately in the smoke-exposed and control lungs. Results The pulmonary [18F]fluorodeoxyglucose uptake rate was increased at 4 h after smoke inhalation (mean ± SD: 0.0031 ± 0.0013 vs. 0.0026 ± 0.0010 min−1, P < 0.05) mainly as a result of increased glucose phosphorylation. At this stage there was no worsening in lung aeration or shunt. However, there was a shift of perfusion toward units with lower ventilation-to-perfusion ratio (mean ratio ± SD: 0.82 ± 0.10 vs. 1.12 ± 0.02, P < 0.05) and increased heterogeneity of the ventilation-perfusion distribution (mean ± SD: 0.21 ± 0.07 vs. 0.13 ± 0.01, P < 0.05). Conclusion Using noninvasive imaging we demonstrated that increased pulmonary [18F]fluorodeoxyglucose uptake and ventilation-perfusion mismatch occur early after smoke inhalation. PMID:24051392

  6. Risk of recurrence in patients with pulmonary embolism: predictive role of D-dimer and of residual perfusion defects on lung scintigraphy.

    PubMed

    Poli, Daniela; Cenci, Caterina; Antonucci, Emilia; Grifoni, Elisa; Arcangeli, Chiara; Prisco, Domenico; Abbate, Rosanna; Miniati, Massimo

    2013-02-01

    The stratification of recurrence risk after a first episode of venous thromboembolism (VTE) is an important topic of research, especially in patients with pulmonary embolism (PE). Elevated D-dimer levels and residual vein obstruction (RVO) at compression ultrasonography have been studied as predictors of recurrence after withdrawing oral anticoagulant treatment (OAT). It is still unknown if residual perfusion defects (PD) on lung scintigraphy are related to recurrent PE. In the present study, we evaluated the association of PD with PE recurrence. The relationship between PD, elevated D-dimer levels, and RVO was also investigated. We prospectively followed 236 consecutive patients who survived a first episode of objectively confirmed PE, with or without deep-vein thrombosis. After at least three months of OAT, treatment was withdrawn in 139 patients. D-dimer levels were evaluated at one month of OAT withdrawal, RVO was measured, and perfusion lung scan (P-scan) was performed to evaluate PD. During follow-up, 20 patients experienced a recurrent episode of VTE. Elevated D-dimer levels were significantly associated with VTE recurrence, (p=0.003). RVO was present in 22% of the patients with recurrence and in 7.5% of those without (p=0.07). No significant association was found between PD >10% and VTE recurrence, D-dimer, or RVO. In conclusion, we confirmed the positive predictive value of elevated D-dimer levels for recurrent VTE. Residual PD on lung scintigraphy are neither predictive of recurrence nor related to D-dimer levels or RVO.

  7. Multipotent adult progenitor cells decrease cold ischemic injury in ex vivo perfused human lungs: an initial pilot and feasibility study.

    PubMed

    La Francesca, Saverio; Ting, Anthony E; Sakamoto, Jason; Rhudy, Jessica; Bonenfant, Nicholas R; Borg, Zachary D; Cruz, Fernanda F; Goodwin, Meagan; Lehman, Nicholas A; Taggart, Jennifer M; Deans, Robert; Weiss, Daniel J

    2014-01-01

    Primary graft dysfunction (PGD) is a significant cause of early morbidity and mortality following lung transplantation. Improved organ preservation techniques will decrease ischemia-reperfusion injury (IRI) contributing to PGD. Adult bone marrow-derived adherent stem cells, including mesenchymal stromal (stem) cells (MSCs) and multipotent adult progenitor cells (MAPCs), have potent anti-inflammatory actions, and we thus postulated that intratracheal MAPC administration during donor lung processing would decrease IRI. The goal of the study was therefore to determine if intratracheal MAPC instillation would decrease lung injury and inflammation in an ex vivo human lung explant model of prolonged cold storage and subsequent reperfusion. Four donor lungs not utilized for transplant underwent 8 h of cold storage (4°C). Following rewarming for approximately 30 min, non-HLA-matched allogeneic MAPCs (1 × 10(7) MAPCs/lung) were bronchoscopically instilled into the left lower lobe (LLL) and vehicle comparably instilled into the right lower lobe (RLL). The lungs were then perfused and mechanically ventilated for 4 h and subsequently assessed for histologic injury and for inflammatory markers in bronchoalveolar lavage fluid (BALF) and lung tissue. All LLLs consistently demonstrated a significant decrease in histologic and BALF inflammation compared to vehicle-treated RLLs. These initial pilot studies suggest that use of non-HLA-matched allogeneic MAPCs during donor lung processing can decrease markers of cold ischemia-induced lung injury.

  8. 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

  9. 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.

  10. Feasibility of quantitative parameters of dynamically enhanced patterns of spiral computed tomography scanning integrated into tumour progression before targeted treatment of non-small cell lung cancer.

    PubMed

    Qiao, Peng-Gang; Huang, Qiong; Zhou, Juan; Wang, Xiang-Chao; Li, Ming; Ma, Jin-Lin; Tian, Ning; Li, Gong-Jie

    2015-04-01

    The relationship between quantitative parameters of contrast-enhanced computed tomography (CT) and non-small cell lung cancer (NSCLC) progression remains controversial. We aimed to explore the usefulness of contrast-enhanced spiral CT scanning for confirming the time of tumour progression before targeted treatment of NSCLC. Contrast-enhanced spiral CT scanning was performed on 33 NSCLC patients with a biopsy-proven diagnosis of NSCLC. All the patients were divided into three groups according to times of tumour progression (<6 weeks, 6-20 weeks, and >20 weeks). The perfusion CT data were used to calculate quantitative parameters, including enhanced peak values, peak time of tumour enhancement, ratio of tumour mass and enhanced aorta peak value and perfusion value of blood flow. Variance analysis was used for statistical analysis among the three groups using SAS 9.13 statistical software. Tumour perfusion values among the three group with different stage of TTP were significantly different from each other with P = 0.0129 (<6 weeks, perfusion value = 0.35 ± 0.15 mL/(min × mL); 6-20 weeks, perfusion value = 0.41 ± 0.086 mL/(min × mL); > 20 weeks, perfusion value = 0.47 ± 0.087 mL/(min × mL)). However, no significant differences were found in other parameters (enhanced peak values, peak time of tumour enhancement, ratios of tumour mass, and enhanced aorta peak value) among three groups (P > 0.05). The NSCLC patients with high perfusion value before targeted therapy are more sensitive to targeted therapy, and further experiments with larger sample size are needed. © 2015 The Royal Australian and New Zealand College of Radiologists.

  11. Non-contrast-enhanced perfusion and ventilation assessment of the human lung by means of fourier decomposition in proton MRI.

    PubMed

    Bauman, Grzegorz; Puderbach, Michael; Deimling, Michael; Jellus, Vladimir; Chefd'hotel, Christophe; Dinkel, Julien; Hintze, Christian; Kauczor, Hans-Ulrich; Schad, Lothar R

    2009-09-01

    Assessment of regional lung perfusion and ventilation has significant clinical value for the diagnosis and follow-up of pulmonary diseases. In this work a new method of non-contrast-enhanced functional lung MRI (not dependent on intravenous or inhalative contrast agents) is proposed. A two-dimensional (2D) true fast imaging with steady precession (TrueFISP) pulse sequence (TR/TE = 1.9 ms/0.8 ms, acquisition time [TA] = 112 ms/image) was implemented on a 1.5T whole-body MR scanner. The imaging protocol comprised sets of 198 lung images acquired with an imaging rate of 3.33 images/s in coronal and sagittal view. No electrocardiogram (ECG) or respiratory triggering was used. A nonrigid image registration algorithm was applied to compensate for respiratory motion. Rapid data acquisition allowed observing intensity changes in corresponding lung areas with respect to the cardiac and respiratory frequencies. After a Fourier analysis along the time domain, two spectral lines corresponding to both frequencies were used to calculate the perfusion- and ventilation-weighted images. The described method was applied in preliminary studies on volunteers and patients showing clinical relevance to obtain non-contrast-enhanced perfusion and ventilation data.

  12. The significance of single V-P mismatches found in Kr-81m/Tc-99m lung scans

    SciTech Connect

    Rosen, J.M.; Palestro, C.J.; Markowitz, D.; Alderson, P.O.

    1985-05-01

    Ventilation-perfusion lung scans demonstrating two or more areas of V-P mismatch (MM) are considered by most nuclear medicine physicians to indicate a high probability of pulmonary embolism (PE). Considerable disagreement exists, however, with regard to the significance of a single area of segmental (S) or subsegmental (SS) MM. The authors reviewed the studies of 22 patients suspected of having PE reviewed the studies of 22 patients suspected of having PE whose lung scans demonstrated a single area of V-P MM and whose diagnosis was confirmed by pulmonary angiography. All V scans were multi-view studies performed with Kr-81m. P scans were performed either with Tc-99m macroaggregated albumin or human albumin microspheres. P defects greater than 75% of the size of a brochopulmonary segment (BPS) were reported as S; defects between 25% and 75% of a BPS were reported as SS. The area of V-P MM was found in the lower lobes in 13 patients, the middle lobe or lingula in 6, and the upper lobes in 3. Of 17 patients with a VP MM and a clear chest x-ray, 4 of 10 patients with a SS MM had PE, as did 4 of 6 patients with a S MM; one patient with a single regional (R) area of V-P MM did not have PE. An additional 5 cases demonstrated a single area of V-P MM and an x-ray opacity of comparable size in the same location; three of these 5 patients had PE. Thus, 11 of the total 22 patients had PE (S:6/9, R:0/2, SS:5/11. The data demonstrate an intermediate level of probability of PE in all subgroups with a single V-P MM, and suggest that V-P lung scans showing a single area of V-P MM should be reported as indeterminate for PE.

  13. An experimental study of the recovery of injured porcine lungs with prolonged normothermic cellular ex vivo lung perfusion following donation after circulatory death.

    PubMed

    Spratt, John R; Mattison, Lars M; Iaizzo, Paul A; Brown, Roland Z; Helms, Haylie; Iles, Tinen L; Howard, Brian; Panoskaltsis-Mortari, Angela; Loor, Gabriel

    2017-09-01

    Donation after circulatory death (DCD) is an underused source of donor lungs. Normothermic cellular ex vivo lung perfusion (EVLP) is effective in preserving standard donor lungs but may also be useful in the preservation and assessment of DCD lungs. Using a model of DCD and prolonged EVLP, the effects of donor warm ischemia and postmortem ventilation on graft recovery were evaluated. Adult male swine underwent general anesthesia and heparinization. In the control group (n = 4), cardioplegic arrest was induced and the lungs were procured immediately. In the four treatment groups, a period of agonal hypoxia was followed by either 1 h of warm ischemia with (n = 4) or without (n = 4) ventilation or 2 h of warm ischemia with (n = 4) or without (n = 4) ventilation. All lungs were studied on an EVLP platform for 24 h. Hemodynamic measures, compliance, and oxygenation on EVLP were worse in all DCD lungs compared with controls. Hemodynamics and compliance normalized in all lungs after 24 h of EVLP, but DCD lungs demonstrated impaired oxygenation. Normothermic cellular EVLP is effective in preserving and monitoring of DCD lungs. Early donor postmortem ventilation and timely procurement lead to improved graft function. © 2017 Steunstichting ESOT.

  14. Phase II multicenter clinical trial of pulmonary metastasectomy and isolated lung perfusion with melphalan in patients with resectable lung metastases.

    PubMed

    den Hengst, Willem A; Hendriks, Jeroen M H; Balduyck, Bram; Rodrigus, Inez; Vermorken, Jan B; Lardon, Filip; Versteegh, Michel I M; Braun, Jerry; Gelderblom, Hans; Schramel, Franz M N H; Van Boven, Wim-Jan; Van Putte, Bart P; Birim, Özcan; Maat, Alexander P W M; Van Schil, Paul E Y

    2014-10-01

    The 5-year overall survival rate of patients undergoing complete surgical resection of pulmonary metastases (PM) from colorectal cancer (CRC) and sarcoma remains low (20-50%). Local recurrence rate is high (48-66%). Isolated lung perfusion (ILuP) allows the delivery of high-dose locoregional chemotherapy with minimal systemic leakage to improve local control. From 2006 to 2011, 50 patients, 28 male, median age 57 years (15-76), with PM from CRC (n = 30) or sarcoma (n = 20) were included in a phase II clinical trial conducted in four cardiothoracic surgical centers. In total, 62 ILuP procedures were performed, 12 bilaterally, with 45 mg of melphalan at 37°C, followed by resection of all palpable PM. Survival was calculated according to the Kaplan-Meier method. Operative mortality was 0%, and 90-day morbidity was mainly respiratory (grade 3: 42%, grade 4: 2%). After a median follow-up of 24 months (3-63 mo), 18 patients died, two without recurrence. Thirty patients had recurrent disease. Median time to local pulmonary progression was not reached. The 3-year overall survival and disease-free survival were 57% ± 9% and 36% ± 8%, respectively. Lung function data showed a decrease in forced expiratory volume in 1 second and diffusing capacity of the alveolocapillary membrane of 21.6% and 25.8% after 1 month, and 10.4% and 11.3% after 12 months, compared with preoperative values. Compared with historical series of PM resection without ILuP, favorable results are obtained in terms of local control without long-term adverse effects. These data support the further investigation of ILuP as additional treatment in patients with resectable PM from CRC or sarcoma.

  15. Pulmonary ventilation and perfusion abnormalities and ventilation perfusion imbalance in children with pulmonary atresia or extreme tetralogy of Fallot

    SciTech Connect

    Dowdle, S.C.; Human, D.G.; Mann, M.D. )

    1990-08-01

    Xenon-133 lung ventilation and perfusion scans were done preoperatively after cardiac catheterization and cineangiocardiography in 19 children; 6 had pulmonary atresia with an intact ventricular septum and hypoplastic right ventricle, 4 pulmonary atresia with associated complex univentricular heart, and 9 extreme Tetralogy of Fallot. The four patients with discrepancies in the sizes of the left and right pulmonary arteries on angiography had marked asymmetry of pulmonary perfusion and ventilation-perfusion imbalance on scintigraphy. Similar degrees of asymmetry and imbalance were present in 6 of the 15 children with equal-size pulmonary vessels. Asymmetry of pulmonary perfusion and ventilation-perfusion imbalance were associated with a poor prognosis.

  16. Why is high resolution computerized tomography scanning used in evaluating the lungs?

    PubMed Central

    Graves, W. A.; Collins, J. D.; Miller, T. Q.

    1989-01-01

    High resolution computerized tomography scans have been used for medical and legal purposes to evaluate patients with a history of exposure to asbestos. Some investigators argue that high resolution scanning provides a better image of the lungs than routine computerized tomography. A review of the literature shows that although high resolution scanning displays the lymphatics in the lung, it offers no new useful diagnostic information. The authors conclude that no real advantage is attained with high resolution scanning of the lung and that pathology of disease can be determined decisively only by histology. Images Figure 1 Figure 2A Figure 2B Figure 3 Figure 4 PMID:2681799

  17. Standardized perfusion value: universal CT contrast enhancement scale that correlates with FDG PET in lung nodules.

    PubMed

    Miles, K A; Griffiths, M R; Fuentes, M A

    2001-08-01

    The standardized enhancement value and standardized perfusion value allow comparison between different methods for quantification of contrast enhancement during computed tomography (CT). Standard perfusion values calculated from CT measurements of perfusion within pulmonary nodules compared favorably with those derived from previously reported enhancement data and correlated with standardized uptake values obtained from positron emission tomographic images (r = 0.8, P <.01).

  18. Pyrrolidine dithiocarbamate administered during ex-vivo lung perfusion promotes rehabilitation of injured donor rat lungs obtained after prolonged warm ischemia

    PubMed Central

    Francioli, Cyril; Wang, Xingyu; Parapanov, Roumen; Abdelnour, Etienne; Lugrin, Jérôme; Gronchi, Fabrizio; Perentes, Jean; Eckert, Philippe; Ris, Hans-Beat; Piquilloud, Lise

    2017-01-01

    Damaged lung grafts obtained after circulatory death (DCD lungs) and warm ischemia may be at high risk of reperfusion injury after transplantation. Such lungs could be pharmacologically reconditioned using ex-vivo lung perfusion (EVLP). Since acute inflammation related to the activation of nuclear factor kappaB (NF-κB) is instrumental in lung reperfusion injury, we hypothesized that DCD lungs might be treated during EVLP by pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-κB. Rat lungs exposed to 1h warm ischemia and 2 h cold ischemia were subjected to EVLP during 4h, in absence (CTRL group, N = 6) or in presence of PDTC (2.5g/L, PDTC group, N = 6). Static pulmonary compliance (SPC), peak airway pressure (PAWP), pulmonary vascular resistance (PVR), and oxygenation capacity were determined during EVLP. After EVLP, we measured the weight gain of the heart-lung block (edema), and the concentration of LDH (cell damage), proteins (permeability edema) and of the cytokines IL-6, TNF-α and CINC-1 in bronchoalveolar lavage (BAL), and we evaluated NF-κB activation by the degree of phosphorylation and degradation of its inhibitor IκBα in lung tissue. In CTRL, we found significant NF-κB activation, lung edema, and a massive release of LDH, proteins and cytokines. SPC significantly decreased, PAWP and PVR increased, while oxygenation tended to decrease. Treatment with PDTC during EVLP inhibited NF-κB activation, did not influence LDH release, but markedly reduced lung edema and protein concentration in BAL, suppressed TNFα and IL-6 release, and abrogated the changes in SPC, PAWP and PVR, with unchanged oxygenation. In conclusion, suppression of innate immune activation during EVLP using the NF-κB inhibitor PDTC promotes significant improvement of damaged rat DCD lungs. Future studies will determine if such rehabilitated lungs are suitable for in vivo transplantation. PMID:28323904

  19. Pyrrolidine dithiocarbamate administered during ex-vivo lung perfusion promotes rehabilitation of injured donor rat lungs obtained after prolonged warm ischemia.

    PubMed

    Francioli, Cyril; Wang, Xingyu; Parapanov, Roumen; Abdelnour, Etienne; Lugrin, Jérôme; Gronchi, Fabrizio; Perentes, Jean; Eckert, Philippe; Ris, Hans-Beat; Piquilloud, Lise; Krueger, Thorsten; Liaudet, Lucas

    2017-01-01

    Damaged lung grafts obtained after circulatory death (DCD lungs) and warm ischemia may be at high risk of reperfusion injury after transplantation. Such lungs could be pharmacologically reconditioned using ex-vivo lung perfusion (EVLP). Since acute inflammation related to the activation of nuclear factor kappaB (NF-κB) is instrumental in lung reperfusion injury, we hypothesized that DCD lungs might be treated during EVLP by pyrrolidine dithiocarbamate (PDTC), an inhibitor of NF-κB. Rat lungs exposed to 1h warm ischemia and 2 h cold ischemia were subjected to EVLP during 4h, in absence (CTRL group, N = 6) or in presence of PDTC (2.5g/L, PDTC group, N = 6). Static pulmonary compliance (SPC), peak airway pressure (PAWP), pulmonary vascular resistance (PVR), and oxygenation capacity were determined during EVLP. After EVLP, we measured the weight gain of the heart-lung block (edema), and the concentration of LDH (cell damage), proteins (permeability edema) and of the cytokines IL-6, TNF-α and CINC-1 in bronchoalveolar lavage (BAL), and we evaluated NF-κB activation by the degree of phosphorylation and degradation of its inhibitor IκBα in lung tissue. In CTRL, we found significant NF-κB activation, lung edema, and a massive release of LDH, proteins and cytokines. SPC significantly decreased, PAWP and PVR increased, while oxygenation tended to decrease. Treatment with PDTC during EVLP inhibited NF-κB activation, did not influence LDH release, but markedly reduced lung edema and protein concentration in BAL, suppressed TNFα and IL-6 release, and abrogated the changes in SPC, PAWP and PVR, with unchanged oxygenation. In conclusion, suppression of innate immune activation during EVLP using the NF-κB inhibitor PDTC promotes significant improvement of damaged rat DCD lungs. Future studies will determine if such rehabilitated lungs are suitable for in vivo transplantation.

  20. [Quantitatively evaluating the evolution of the tumor perfusion in A549 lung adenocarcinoma transplantation model induced by antiangiogenic treatment].

    PubMed

    Xiong, Zeng; Deng, Pengbo; Hu, Chengping; Liu, Jinkang; Yang, Huaping; Zhou, Jianhua; Wang, Ying; Zhou, Hui; Zhu, Zhiming

    2016-01-26

    To quantitatively evaluate the evolution of the tumor perfusion in A549 lung adenocarcinoma transplantation model induced by antiangiogenic treatment. To establish the preclinical transplantation model of lung adenocarcinoma, 60 BALB/c nu/nu mice was inoculated with A549 cell lines via axilla. Sixty mice were randomly divided into 2 groups. The treatment group was treated with intravenous Bevacizumab (10 mg/kg weight, in a single injection), and the control group received saline only in the same dose. Five times of volume perfusion CT (VPCT) scan was performed before treatment, and on the second, forth, sixth and tenth days of treatment, respectively. The values of blood flow (BF) in the A549 tumors were measured after scanning. The microvessel density (MVD), vessel maturity index (VMI) in the tumors were determined using multiplexed QDs-based immunohistochemical staining. Comparing the values of BF, VMI and MVD between the two groups on the same day before treatment, the values of BF, VMI and MVD of the treatment group were (13.5±1.5) ml·(100 ml)(-1)·min(-1,) 0.14±0.04, (45.7±16.5)/HPF, respectively, and those in the control group were (13.4±1.6) ml·(100 ml)(-1)·min(-1) , 0.14±0.05, (48.0±7.0) /HPF , respectively. There was no significant difference between the two groups (all P>0.05). And on the second, forth, sixth, tenth days of treatment, the values of BF of the treatment group were (17.9±7.3), (32.2±6.9), (18.5±2.4) and (13.8±1.8) ml·(100 ml)(-1)·min(-1,) respectively, and those in the control group were (10.5±0.6), (9.6±0.8), (5.7±1.2) and (1.9±1.0) ml·(100 ml)(-1)·min(-1,) respectively. The values of VMI of the treatment group were 1.17±0.22, 3.25±0.23, 2.94±0.31 and 1.07±0.18, respectively, and those in the control group were 0.12±0.03, 0.13±0.03, 0.15±0.03, and 0.13±0.03, respectively. The values of MVD of the treatment group were (38.0±6.3), (24.3±5.4), (15.2±3.4) and (13.5±4.7)/HPF, respectively, and those in the

  1. Preoperative cardiac evaluation by dipyridamole thallium-201 myocardial perfusion scan provides no benefit in patients with abdominal aortic aneurysm.

    PubMed

    Shin, Sung; Kwon, Tae-Won; Cho, Yong-Pil; Lee, Jong-Young; Park, Hojong; Han, Youngjin

    2013-12-01

    The purpose of the present study was to evaluate the benefits of a preoperative dipyridamole thallium-201 myocardial perfusion scan in patients undergoing abdominal aortic aneurysm (AAA) repair. We retrospectively reviewed findings in a prospectively collected database of patients undergoing open or endovascular repair of AAA at the Asan Medical Center, Seoul, Korea, from January 2001 to May 2011. Of 373 patients, 11 (2.9 %) had postoperative myocardial infarction (MI), whereas 24 (6.4 %), 17 (4.6 %), 24 (6.4 %), and 8 (2.1 %) were diagnosed with myocardial ischemia, atrial fibrillation, ventricular arrhythmia, and congestive heart failure, respectively. The incidence of 30-day cardiac-related mortality was 1.6 % (6 of 373 patients). The preoperative variables significantly associated with postoperative cardiac events in multivariate analysis were preoperative congestive heart failure (odds ratio [OR] 8.8, 95 % confidence interval [CI] 1.36-56.73, p = 0.022), long-acting nitrates (OR 8.1, 95 % CI 1.22-54.26, p = 0.03), and body mass index (BMI) higher than 26 (OR 3.6, 95 % CI 1.49-8.48, p = 0.004). The variables obtained from dipyridamole thallium-201 myocardial perfusion scan were not correlates of postoperative cardiac events. The sensitivity of reversible defects for postoperative cardiac events was 14 % and the specificity was 90 %. Subgroup analyses revealed that thallium defects were not significant variables in predicting postoperative cardiac events in patients with coronary artery disease (CAD) or in no-CAD patients. Preoperative dipyridamole thallium-201 myocardial perfusion scans were ineffective in predicting postoperative cardiac complications in AAA patients. These results suggest that the routine use of these tests for preoperative screening of patients undergoing AAA repair may not be warranted.

  2. Pulmonary vasomotor nerve responses in isolated perfused lungs of Macaca mulatta and Papio species.

    PubMed Central

    de Burgh Daly, I; Ramsay, D J; Waaler, B A

    1975-01-01

    1. Lung lobes of Macaca mulatta and Papio species were isolated from the body and perfused by a pump delivering a constant volume inflow. The left atrial pressure was kept constant and therefore any recorded change in pulmonary arterial pressure reflected a change in pulmonary vascular resistance. 2. In five Macaca mulatta preparations stimulation of the upper thoracic sympathetic chain, the stellate ganglion, the middle cervical ganglion and the thoracic vagosympathetic nerve caused a small increase in calculated pulmonary vascular resistance usually followed by a larger decrease. Evidence is produced which suggests that the depressor response is mediated by adrenergic beta-receptors. In three preparations no change in pulmonary vascular resistance occurred. 3. In four Papio preparations stimulation of similar nerves invariably caused an increase in calculated pulmonary vascular resistance. In one animal no change in vascular resistance occurred. 4. A regression analysis of the results showed an inverse relationship between the magnitude of the pulmonary vascular response to nerve stimulation and the degree of excitement of the animals during capture, restraint and anaesthesia (P less than 0.01). Images Fig. 2 PMID:809575

  3. Preparation of Tc-99m-macroaggregated albumin from recombinant human albumin for lung perfusion imaging.

    PubMed

    Hunt, A P; Frier, M; Johnson, R A; Berezenko, S; Perkins, A C

    2006-01-01

    Human serum albumin (HSA) extracted from pooled blood taken from human donors is used in the production of (99m)Tc-labelled macroaggregated albumin (MAA) for lung perfusion imaging. However, concerns for the safety of blood-derived products due to potential contamination by infective agents (e.g. new variant CJD), make alternative production methods necessary. Recombinant DNA technology is a promising method of albumin production avoiding problems associated with human-derived HSA. This paper presents results comparing MAA prepared from recombinant human albumin (rHA, Recombumin) (rMAA) with in-house produced HSA MAA (hMAA) and commercially available MAA (cMAA). (99m)Tc-MAA was prepared using previously published production methods by heating a mixture of albumin and stannous chloride in acetate buffer (pH 5.4) at 70 degrees C for 20 min. Parameters investigated include aggregate size, radiolabelling efficiency, radiochemical and aggregate stability at 4 degrees C and in vitro (in whole human blood) at 37 degrees C and biodistribution studies. Results showed that rMAA could be produced with similar morphology, labelling efficiency and stability to hMAA and cMAA. Our findings confirm that rHA shows significant potential as a direct replacement for HSA in commercially available MAA.

  4. Can CT pulmonary angiography replace ventilation-perfusion scans as a first line investigation for pulmonary emboli?

    PubMed

    McEwan, L; Gandhi, M; Andersen, J; Manthey, K

    1999-08-01

    A prospective study was performed to determine efficacy of diagnosis of pulmonary emboli by computed tomographic pulmonary angiography (CTPA) in patients who underwent both CTPA and ventilation-perfusion (V/Q) scanning. The results were compared with the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study in which conventional pulmonary angiography had been performed instead of CTPA. Forty-two of 161 (26%) patients had a positive CTPA compared with a 27% prevalence in the PIOPED population. Fourteen of 16 patients (87.5%) with high-probability V/Q scans also had a positive CTPA compared with 87% in PIOPED. Twelve of 40 patients (30%) with intermediate probability V/Q scans also had a positive CTPA compared with 34.7% in PIOPED, while 12 of 80 patients (15%) who had low-probability V/Q scans had positive CTPA compared with 14.5% in PIOPED. Four of 25 patients (16%) with normal V/Q scans had positive CTPA compared with 0% in PIOPED. While the present study size was relatively small, the results compared favourably with PIOPED, suggesting that equivalent prevalence of clot was being detected using CTPA. This result, together with the cost considerations, has led us to replace V/Q scanning with CTPA for investigation of the majority of cases of suspected, acute pulmonary emboli.

  5. The First Experience of Ex-Vivo Lung Perfusion (EVLP) in Iran: An Effective Method to Increase Suitable Lung for Transplantation

    PubMed Central

    Shafaghi, S.; Najafizadeh, K.; Sheikhy, K.; Ansari Aval, Z.; Farzanegan, B.; Mafhoomi, Y.; Faghih Abdollahi, Z.; Emami, H.; Mortaz, E.; Porabdollah, M.; Jahangiri Fard, A.; Nikobayan Safaei, M.; Slama, A.; Aigner, C.; Hosseini-Baharanchi, F. S.; Abbasi Dezfuli, A.

    2016-01-01

    Background: Although lung transplantation is a well-accepted treatment for end-stage lung diseases patients, only 15%–20% of the brain-dead donors’ lungs are usable for transplantation. This results in high mortality of candidates on waiting lists. Ex-vivo lung perfusion (EVLP) is a novel method for better evaluation of a potential lung for transplantation. Objective: To report the first experience of EVLP in Iran. Methods: The study included a pig in Vienna Medical University, Vienna, Austria, and 4 humans in Masih Daneshvari Hospital, Tehran, Iran. All brain-dead donors from 2013 to 2015 in Tehran were evaluated for EVLP. Donors without signs of severe chest trauma or pneumonia, with poor oxygenation were included. Results: An increasing trend in difference between the pulmonary arterial pO2 and left atrial pO2, an increasing pattern in dynamic lung compliance, and a decreasing trend in the pulmonary vascular resistance, were observed. Conclusion: The initial experience of EVLP in Iran was successful in terms of important/critical parameters. The results emphasize on some important considerations such as precisely following standard lung harvesting and monitoring temperature and pressure. EVLP technique may not be a cost-effective option for low-income countries at first glance. However, because this is the only therapeutic treatment for end-stage lung disease, it is advisable to continue working on this method to find alternatives with lesser costs. PMID:28078061

  6. Whole-tumor perfusion CT in patients with advanced lung adenocarcinoma treated with conventional and antiangiogenetic chemotherapy: initial experience.

    PubMed

    Fraioli, Francesco; Anzidei, Michele; Zaccagna, Fulvio; Mennini, Maria Luisa; Serra, Goffredo; Gori, Bruno; Longo, Flavia; Catalano, Carlo; Passariello, Roberto

    2011-05-01

    To determine whether wide-volume perfusion computed tomography (CT) performed with a new generation scanner can allow evaluation of the effects of chemotherapy combined with antiangiogenetic treatment on the whole tumor mass in patients with locally advanced lung adenocarcinoma and to determine if changes in CT numbers correlate with the response to therapy as assessed by conventional response evaluation criteria in solid tumors (RECIST). Forty-five patients with unresectable lung adenocarcinoma underwent perfusion CT before and 40 and 90 days after chemotherapy and antiangiogenetic treatment. RECIST measurements and calculations of blood flow, blood volume, time to peak, and permeability were performed by two independent blinded radiologists. Pearson correlation coefficient was used to assess the correlation between baseline CT numbers. Baseline and follow-up perfusion parameters of the neoplastic lesions were tested overall for statistically significant differences by using the repeated-measures analysis of variance and then were also compared on the basis of the therapy response assessed according to the RECIST criteria. Pearson correlation coefficient showed a significant correlation between baseline values of blood flow and blood volume (ρ = 0.48; P = .001), time to peak and permeability (ρ = 0.31; P = .04), time to peak and blood flow (ρ = -0.66; P < .001), and time to peak and blood volume (ρ = -0.39; P = .007). Blood flow, blood volume, and permeability values were higher in responding patients than in the other patients, with a significant difference at second follow-up for blood flow (P = .0001), blood volume (P = .02), and permeability (P = .0001); time to peak was higher in nonresponding patients (P = .012). Perfusion CT imaging may allow evaluation of lung cancer angiogenesis demonstrating alterations in vascularity following treatment. RSNA, 2011

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

    PubMed

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

    2016-01-19

    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.

  8. Is it possible to further improve the function of pulmonary grafts by extending the duration of lung reconditioning using ex vivo lung perfusion?

    PubMed

    Pierre, L; Lindstedt, S; Hlebowicz, J; Ingemansson, R

    2013-07-01

    The method of ex vivo lung perfusion (EVLP) has been suggested as a reliable means of differentiating between "good" and "poor" pulmonary grafts in marginal donors as, when grafts identified as good by this method are transplanted, the results do not differ from those using lungs fulfilling standard criteria. The EVLP method is also thought to improve pulmonary grafts by reducing lung edema and eliminating lung atelectasis. In the present study, we investigated whether the pulmonary graft could be further improved by extending the duration of EVLP. Six Landrace pigs were used. The lungs were reconditioned and evaluated, using the EVLP method, as double lungs. After the initial evaluation, EVLP was continued for a further 90 minutes. The arterial oxygen level (pO2) was 60.8 ± 4.8 kPa after the standard 60 minutes of EVLP and 67.1 ± 2.2 kPa after 150 minutes (p = 0.48). The pulmonary vascular resistance was 453 ± 78 dyne*s/cm(5) after 60, 90, 120 and 150 minutes of EVLP (p = 1.0). The pulmonary artery pressure was 17.8 ± 1.0 mmHg after 60, 90, 120, and 150 minutes of EVLP (p = 1.0) and the pulmonary artery flow was 3.5 ± 0.4 l/min after 60, 90, 120, and 150 minutes of EVLP (p = 1.0). The mean weight of the pulmonary grafts after harvesting was 574 ± 20 g at the beginning of EVLP 541 ± 24 g and, after 150 min of EVLP, 668 ± 33 (p = 0.011). The blood gases and hemodynamic parameters in the pulmonary grafts did not improve as a result of the extra 90 minutes of EVLP. However, the weight of the pulmonary graft increased significantly with increasing duration of EVLP, indicating lung perfusion injury.

  9. Acute Pyelonephritis Focusing on Perfusion Defects on Contrast Enhansed Computerized Tomography(CT) Scans and Its Clinical Outcome

    PubMed Central

    Ha, Sung-Kyu; Seo, Jung-Kun; Kim, Seung-Jung; Park, Seung-Ho; Park, Chong-Hoon; Lee, Ho-Yung; Han, Dae-Suk; Kim, Ki-Whang

    1997-01-01

    subgroups of group 1 in the duration of defeverscence. Conclusion Those patients who had perfusion defects on CT showed relatively severe clinical courses but responses to early antibiotics were very good. Contrast enhanced CT scans may be very sensitive for the detection of acute renal parenchymal inflammatory disease and for defining the extent of disease, but it is clinically not essential to perform in the early uncomplicated acute pyelonephritis because CT diagnosis does not change management. Clinical use of contrast enhanced CT scan may be appropriate in case of persistence of fever and leukocytosis for more than seven days despite antibiotic treatment. PMID:9439146

  10. Successful Transplantation of Lungs From an Uncontrolled Donor After Circulatory Death Preserved In Situ by Alveolar Recruitment Maneuvers and Assessed by Ex Vivo Lung Perfusion.

    PubMed

    Valenza, F; Citerio, G; Palleschi, A; Vargiolu, A; Fakhr, B Safaee; Confalonieri, A; Nosotti, M; Gatti, S; Ravasi, S; Vesconi, S; Pesenti, A; Blasi, F; Santambrogio, L; Gattinoni, L

    2016-04-01

    We developed a protocol to procure lungs from uncontrolled donors after circulatory determination of death (NCT02061462). Subjects with cardiovascular collapse, treated on scene by a resuscitation team and transferred to the emergency room, are considered potential donors once declared dead. Exclusion criteria include unwitnessed collapse, no-flow period of >15 min and low flow >60 min. After death, lung preservation with recruitment maneuvers, continuous positive airway pressure, and protective mechanical ventilation is applied to the donor. After procurement, ex vivo lung perfusion (EVLP) is performed. From November 2014, 10 subjects were considered potential donors; one of these underwent the full process of procurement, EVLP, and transplantation. The donor was a 46-year-old male who died because of thoracic aortic dissection. Lungs were procured 4 h and 48 min after death, and deemed suitable for transplantation after EVLP. Lungs were then offered to a rapidly deteriorating recipient with cystic fibrosis (lung allocation score [LAS] 46) who consented to the transplant in this experimental setting. Six months after transplantation, the recipient is in good condition (forced expiratory volume in 1 s 85%) with no signs of rejection. This protocol allowed procurement of lungs from an uncontrolled donor after circulatory determination of death following an extended period of warm ischemia. © 2015 The Authors. American Journal of Transplantation published by Wiley Periodicals, Inc. on behalf of American Society of Transplant Surgeons.

  11. Ex vivo Perfusion with Adenosine A2A Receptor Agonist Enhances Rehabilitation of Murine Donor Lungs after Circulatory Death

    PubMed Central

    Stone, Mathew L.; Sharma, Ashish K.; Mas, Valeria. R.; Gehrau, Ricardo C.; Mulloy, Daniel P.; Zhao, Yunge; Lau, Christine L.; Kron, Irving L.; Laubach, Victor E.

    2015-01-01

    Background Ex vivo lung perfusion (EVLP) enables assessment and rehabilitation of marginal donor lungs prior to transplantation. We previously demonstrated that adenosine A2A receptor (A2AR) agonism attenuates lung ischemia-reperfusion injury. The current study utilizes a novel murine EVLP model to test the hypothesis that A2AR agonist enhances EVLP-mediated rehabilitation of donation after circulatory death (DCD) lungs. Methods Mice underwent euthanasia and 60 min warm ischemia, and lungs were flushed with Perfadex and underwent cold static preservation (CSP, 60 min). Three groups were studied: no EVLP (CSP), EVLP with Steen solution for 60 min (EVLP), and EVLP with Steen solution supplemented with ATL1223, a selective A2AR agonist (EVLP+ATL1223). Lung function, wet/dry weight, cytokines and neutrophil numbers were measured. Microarrays were performed using the Affymetrix GeneChip Mouse Genome 430A 2.0 Array. Results EVLP significantly improved lung function versus CSP, which was further, significantly improved by EVLP+ATL1223. Lung edema, cytokines and neutrophil counts were reduced after EVLP and further, significantly reduced after EVLP+ATL1223. Gene array analysis revealed differential expression of 1,594 genes after EVLP, which comprise canonical pathways involved in inflammation and innate immunity including IL-1, IL-8, IL-6 and IL-17 signaling. Several pathways were uniquely regulated by EVLP+ATL1223 including the downregulation of genes involved in IL-1 signaling such as ADCY9, ECSIT, IRAK1, MAPK12 and TOLLIP. Conclusion EVLP modulates pro-inflammatory genes and reduces pulmonary dysfunction, edema and inflammation in DCD lungs, which are further reduced by A2AR agonism. This murine EVLP model provides a novel platform to study rehabilitative mechanisms of DCD lungs. PMID:26262504

  12. Determination of clinical efficacy: nuclear medicine as applied to lung scanning

    SciTech Connect

    Saenger, E.L.; Buncher, C.R.; Specker, B.L.; McDevitt, R.A.

    1985-07-01

    This paper describes a Society of Nuclear Medicine sponsored study of 2023 patients which compares two methods, logistic regression (LR) and entropy minimax pattern detection (EMPD), to evaluate efficacy. Lung scans, used in determining or excluding a diagnosis of pulmonary embolism (PE), were utilized to create the data set. The LR analysis, presented here, shows that lung scan findings have significant influence on the referring physician's diagnostic thinking. Models were developed for the probability of a signout diagnosis of PE, and equal patient groups tested the validity of these regression equations. A comparison of the sensitivity, specificity, and predictive values of EMPD and LR was done. EMPD predicts a signout diagnosis on only 41% of cases before lung scan and 71% after lung scan; LR provides a prediction of the signout diagnosis on 100% of cases. An advantage of EMPD is that it does not require poor probability estimates.

  13. Dynamic contrast-enhanced MRI perfusion for differentiating between melanoma and lung cancer brain metastases.

    PubMed

    Hatzoglou, Vaios; Tisnado, Jamie; Mehta, Alpesh; Peck, Kyung K; Daras, Mariza; Omuro, Antonio M; Beal, Kathryn; Holodny, Andrei I

    2017-04-01

    Brain metastases originating from different primary sites overlap in appearance and are difficult to differentiate with conventional MRI. Dynamic contrast-enhanced (DCE)-MRI can assess tumor microvasculature and has demonstrated utility in characterizing primary brain tumors. Our aim was to evaluate the performance of plasma volume (Vp) and volume transfer coefficient (K(trans) ) derived from DCE-MRI in distinguishing between melanoma and nonsmall cell lung cancer (NSCLC) brain metastases. Forty-seven NSCLC and 23 melanoma brain metastases were retrospectively assessed with DCE-MRI. Regions of interest were manually drawn around the metastases to calculate Vpmean and Kmeantrans. The Mann-Whitney U test and receiver operating characteristic analysis (ROC) were performed to compare perfusion parameters between the two groups. The Vpmean of melanoma brain metastases (4.35, standard deviation [SD] = 1.31) was significantly higher (P = 0.03) than Vpmean of NSCLC brain metastases (2.27, SD = 0.96). The Kmeantrans values were higher in melanoma brain metastases, but the difference between the two groups was not significant (P = 0.12). Based on ROC analysis, a cut-off value of 3.02 for Vpmean (area under curve = 0.659 with SD = 0.074) distinguished between melanoma brain metastases and NSCLC brain metastases (P < 0.01) with 72% specificity. Our data show the DCE-MRI parameter Vpmean can differentiate between melanoma and NSCLC brain metastases. The ability to noninvasively predict tumor histology of brain metastases in patients with multiple malignancies can have important clinical implications.

  14. Changes in Global Function and Regional Ventilation and Perfusion on SPECT During the Course of Radiotherapy in Patients With Non-Small-Cell Lung Cancer

    SciTech Connect

    Yuan Shuanghu; Frey, Kirk A.; Gross, Milton D.; Hayman, James A.; Arenberg, Doug; Cai Xuwei; Ramnath, Nithya; Hassan, Khaled; Moran, Jean; Eisbruch, Avraham; Ten Haken, Randall K.; Kong Fengming

    2012-03-15

    Purpose: This study aimed to (1) examine changes in dyspnea, global pulmonary function test (PFT) results, and functional activity on ventilation (V)/perfusion (Q) single-photon emission computerized tomography (SPECT) scans during the course of radiation (RT), and (2) factors associated with the changes in patients with non-small-cell lung cancer (NSCLC). Methods and Materials: Fifty-six stage I to III NSCLC patients treated with definitive RT with or without chemotherapy were enrolled prospectively. Dyspnea was graded according to Common Terminology Criteria for Adverse Events version 3.0 prior to and weekly during RT. V/Q SPECT-computed tomography (CT) and PFTs were performed prior to and during RT at approximately 45 Gy. Functions of V and Q activities were assessed using a semiquantitative scoring of SPECT images. Results: Breathing improved significantly at the third week (mean dyspnea grade, 0.8 vs. 0.6; paired t-test p = 0.011) and worsened during the later course of RT (p > 0.05). Global PFT results did not change significantly, while regional lung function on V/Q SPECT improved significantly after {approx}45 Gy. The V defect score (DS) was 4.9 pre-RT versus 4.3 during RT (p = 0.01); Q DS was 4.3 pre-RT versus 4.0 during RT (p < 0.01). Improvements in V and Q functions were seen primarily in the ipsilateral lung (V DS, 1.9 pre-RT versus 1.4 during RT, p < 0.01; Q DS, 1.7 pre-RT versus 1.5 during RT, p < 0.01). Baseline primary tumor volume was significantly correlated with pre-RT V/Q DS (p < 0.01). Patients with central lung tumors had greater interval changes in V and Q than those with more peripheral tumors (p <0.05 for both V and Q DS). Conclusions: Regional ventilation and perfusion improved during RT at 45 Gy. This suggests that adaptive planning based on V/Q SPECT during RT may allow sparing of functionally recoverable lung tissue.

  15. [Effect of using several levels of positive end-expiratory pressure over barotrauma's induced lung injury in a model of isolated and perfused rabbit lungs].

    PubMed

    Trejo, Humberto; Urich, Daniela; Pezzulo, Alejandro; Novoa, Eva; Marcano, Héctor; Crespo, Astrid; Sánchez de León, Roberto

    2006-03-01

    The use of Positive end-expiratory pressure (PEEP) as a strategy of mechanical ventilation offers its advantages, such as improved oxygenation, without causing alveolar overstretching and barotrauma. We aim to investigate the effect of several levels of PEEP on barotrauma and, whether an optimal level of PEEP exists. Forty-eight New Zealand rabbits (2.5-3.5 kg) were divided into four groups with PEEP settings of 0, 4, 8 and 12 cmH2O, at increasing levels of inspiratory volume (IV). This was done in blood perfused rabbit lungs and in lungs perfused with a Buffer-Albumin Solution. We observed that lungs ventilated with PEEP 0 cmH2O suffered pulmonary rupture at high IV (300cc), with significant increases of Pap (Pulmonary artery pressure) and FFR (Fluid filtration rate). Lungs ventilated with PEEP 8 and 12 suffered pulmonary rupture at lower IV (200cc and 150cc vs. 300cc respectively) On the other hand, lungs ventilated with PEEP 4 cmH2O reached the highest IV (400cc), in addition, they showed the lowest elevations of Pap and FFR. The acellular lungs ventilated with PEEP 4, 8 and 12 showed pulmonary rupture at lower IV when compared with cellular ones (300cc vs. 400cc: 100cc vs. 200cc and 100cc vs. 150cc respectively). We concluded that an optimal PEEP exists, which protects against barotrauma, however, excess of PEEP could enhance its development. The blood could contain some mediators which attenuate the damage induced by barotrauma.

  16. The effect of blood perfusion rate on the temperature distributions induced by multiple, scanned and focused ultrasonic beams in dogs' kidneys in vivo.

    PubMed

    Hynynen, K; DeYoung, D; Kundrat, M; Moros, E

    1989-01-01

    The effect of blood perfusion rate on the temperature distribution during scanned, focused ultrasound hyperthermia was investigated using an in vivo dog kidney model. The results showed that the ultrasound beams could penetrate through the body wall without severe distortion, and that they could be used to induce controlled temperature elevations in the target volume. The blood perfusion rate of the heated tissue significantly modified the temperature distribution and the temperatures achieved in the kidney with no flow were about five times higher than in the case with full flow for the same applied acoustic power. It was also demonstrated that the power deposition pattern produced by scanned focused ultrasonic fields could be modified to give an acceptable temperature distribution in different perfusion situations. Similar trends were also obtained by using the bioheat transfer equation to simulate the experiment. Both the magnitude of the temperature elevations and the effect of perfusion on the temperature distributions obtained in the experiments were in agreement with the simulations. The main difference occurred at high perfusion rates where the experiments showed significant temperature elevation outside of the scanned volume and the simulation results predicted hardly any temperature increase 5 mm outside the scan. These observations indicate that both the theoretical power calculation programme and the temperature simulations will have value in the design of optimal heating systems, treatment planning and in the retrospective of the achieved temperature distributions.

  17. Lung injury after simulated cardiopulmonary bypass in an isolated perfused rat lung preparation: Role of mitogen-activated protein kinase/Akt signaling and the effects of theophylline

    PubMed Central

    Markou, Thomais; Chambers, David J.

    2014-01-01

    Objectives Lung deflation and inflation during cardiac surgery with cardiopulmonary bypass contributes to pulmonary dysfunction postoperatively. Theophylline treatment for lung diseases has traditionally been thought to act by phosphodiesterase inhibition; however, increasing evidence has suggested other plausible mechanisms. We investigated the effects of deflation and reinflation on signaling pathways (p38-mitogen-activated protein kinase [MAPK], extracellular signal-regulated kinase 1 and 2 [ERK1/2], and Akt) and whether theophylline influences the deflation-induced lung injury and associated signaling. Methods Isolated rat lungs were perfused (15 mL/min) with deoxygenated rat blood in bicarbonate buffer and ventilated. After 20 minutes' equilibration, the lungs were deflated (60 minutes, aerobic perfusion 1.5 mL/min), followed by reinflation (60 minutes, anaerobic reperfusion 15 mL/min). Compliance, vascular resistance, and kinase phosphorylation were assessed during deflation and reinflation. The effects of SB203580 (50 μM), a p38-MAPK inhibitor, and theophylline (0.083 mM [therapeutic] or 3 mM [supratherapeutic]) on physiology and signaling were studied. Results Deflation reduced compliance by 44% compared with continuously ventilated lungs. p38-MAPK and Akt phosphorylation increased (three to fivefold) during deflation and reinflation, and ERK1/2 phosphorylation increased (approximately twofold) during reinflation. SB203580 had no effect on lung physiology or ERK1/2 and Akt activation. Both theophylline doses increased cyclic adenosine monophosphate, but only 3 mM theophylline improved compliance. p38-MAPK phosphorylation was not affected by theophylline; 0.083 mM theophylline inhibited reinflation-induced ERK1/2 phosphorylation (72% ± 3%); and 3 mM theophylline inhibited Akt phosphorylation during deflation (75% ± 5%) and reinflation (87% ± 4%). Conclusions Lung deflation and reinflation stimulates differential p38-MAPK, ERK1/2, and Akt activation

  18. Lung injury after simulated cardiopulmonary bypass in an isolated perfused rat lung preparation: Role of mitogen-activated protein kinase/Akt signaling and the effects of theophylline.

    PubMed

    Markou, Thomais; Chambers, David J

    2014-11-01

    Lung deflation and inflation during cardiac surgery with cardiopulmonary bypass contributes to pulmonary dysfunction postoperatively. Theophylline treatment for lung diseases has traditionally been thought to act by phosphodiesterase inhibition; however, increasing evidence has suggested other plausible mechanisms. We investigated the effects of deflation and reinflation on signaling pathways (p38-mitogen-activated protein kinase [MAPK], extracellular signal-regulated kinase 1 and 2 [ERK1/2], and Akt) and whether theophylline influences the deflation-induced lung injury and associated signaling. Isolated rat lungs were perfused (15 mL/min) with deoxygenated rat blood in bicarbonate buffer and ventilated. After 20 minutes' equilibration, the lungs were deflated (60 minutes, aerobic perfusion 1.5 mL/min), followed by reinflation (60 minutes, anaerobic reperfusion 15 mL/min). Compliance, vascular resistance, and kinase phosphorylation were assessed during deflation and reinflation. The effects of SB203580 (50 μM), a p38-MAPK inhibitor, and theophylline (0.083 mM [therapeutic] or 3 mM [supratherapeutic]) on physiology and signaling were studied. Deflation reduced compliance by 44% compared with continuously ventilated lungs. p38-MAPK and Akt phosphorylation increased (three to fivefold) during deflation and reinflation, and ERK1/2 phosphorylation increased (approximately twofold) during reinflation. SB203580 had no effect on lung physiology or ERK1/2 and Akt activation. Both theophylline doses increased cyclic adenosine monophosphate, but only 3 mM theophylline improved compliance. p38-MAPK phosphorylation was not affected by theophylline; 0.083 mM theophylline inhibited reinflation-induced ERK1/2 phosphorylation (72%±3%); and 3 mM theophylline inhibited Akt phosphorylation during deflation (75%±5%) and reinflation (87%±4%). Lung deflation and reinflation stimulates differential p38-MAPK, ERK1/2, and Akt activation, suggesting a role in lung injury during

  19. 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

  20. Acute tumor vascular effects following fractionated radiotherapy in human lung cancer: In vivo whole tumor assessment using volumetric perfusion computed tomography

    SciTech Connect

    Ng, Q.-S.; Goh, Vicky; Milner, Jessica; Padhani, Anwar R.; Saunders, Michele I.; Hoskin, Peter J. . E-mail: peterhoskin@nhs.net

    2007-02-01

    Purpose: To quantitatively assess the in vivo acute vascular effects of fractionated radiotherapy for human non-small-cell lung cancer using volumetric perfusion computed tomography (CT). Methods and Materials: Sixteen patients with advanced non-small-cell lung cancer, undergoing palliative radiotherapy delivering 27 Gy in 6 fractions over 3 weeks, were scanned before treatment, and after the second (9 Gy), fourth (18 Gy), and sixth (27 Gy) radiation fraction. Using 16-detector CT, multiple sequential volumetric acquisitions were acquired after intravenous contrast agent injection. Measurements of vascular blood volume and permeability for the whole tumor volume were obtained. Vascular changes at the tumor periphery and center were also measured. Results: At baseline, lung tumor vascularity was spatially heterogeneous with the tumor rim showing a higher vascular blood volume and permeability than the center. After the second, fourth, and sixth fractions of radiotherapy, vascular blood volume increased by 31.6% (paired t test, p = 0.10), 49.3% (p = 0.034), and 44.6% (p = 0.0012) respectively at the tumor rim, and 16.4% (p = 0.29), 19.9% (p = 0.029), and 4.0% (p = 0.0050) respectively at the center of the tumor. After the second, fourth, and sixth fractions of radiotherapy, vessel permeability increased by 18.4% (p = 0.022), 44.8% (p = 0.0048), and 20.5% (p = 0.25) at the tumor rim. The increase in permeability at the tumor center was not significant after radiotherapy. Conclusion: Fractionated radiotherapy increases tumor vascular blood volume and permeability in human non-small-cell lung cancer. We have established the spatial distribution of vascular changes after radiotherapy; greater vascular changes were demonstrated at the tumor rim compared with the center.

  1. Lungs donated after circulatory death and prolonged warm ischemia are transplanted successfully after enhanced ex vivo lung perfusion using adenosine A2B receptor antagonism.

    PubMed

    Charles, Eric J; Mehaffey, J Hunter; Sharma, Ashish K; Zhao, Yunge; Stoler, Mark H; Isbell, James M; Lau, Christine L; Tribble, Curtis G; Laubach, Victor E; Kron, Irving L

    2017-04-12

    The current supply of acceptable donor lungs is not sufficient for the number of patients awaiting transplantation. We hypothesized that ex vivo lung perfusion (EVLP) with targeted drug therapy would allow successful rehabilitation and transplantation of donation after circulatory death lungs exposed to 2 hours of warm ischemia. Donor porcine lungs were procured after 2 hours of warm ischemia postcardiac arrest and subjected to 4 hours of cold preservation or EVLP. ATL802, an adenosine A2B receptor antagonist, was administered to select groups. Four groups (n = 4/group) were randomized: cold preservation (Cold), cold preservation with ATL802 during reperfusion (Cold + ATL802), EVLP (EVLP), and EVLP with ATL802 during ex vivo perfusion (EVLP + ATL802). Lungs subsequently were transplanted, reperfused, and assessed by measuring dynamic lung compliance and oxygenation capacity. EVLP + ATL802 significantly improved dynamic lung compliance compared with EVLP (25.0 ± 1.8 vs 17.0 ± 2.4 mL/cmH2O, P = .04), and compared with cold preservation (Cold: 12.2 ± 1.3, P = .004; Cold + ATL802: 10.6 ± 2.0 mL/cmH2O, P = .002). Oxygenation capacity was highest in EVLP (440.4 ± 37.0 vs Cold: 174.0 ± 61.3 mm Hg, P = .037). No differences in oxygenation or pulmonary edema were observed between EVLP and EVLP + ATL802. A significant decrease in interleukin-12 expression in tissue and bronchoalveolar lavage was identified between groups EVLP and EVLP + ATL802, along with less neutrophil infiltration. Severely injured donation after circulatory death lungs subjected to 2 hours of warm ischemia are transplanted successfully after enhanced EVLP with targeted drug therapy. Increased use of lungs after uncontrolled donor cardiac death and prolonged warm ischemia may be possible and may improve transplant wait list times and mortality. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  2. Automatic lung segmentation from thoracic computed tomography scans using a hybrid approach with error detection

    SciTech Connect

    Rikxoort, Eva M. van; Hoop, Bartjan de; Viergever, Max A.; Prokop, Mathias; Ginneken, Bram van

    2009-07-15

    Lung segmentation is a prerequisite for automated analysis of chest CT scans. Conventional lung segmentation methods rely on large attenuation differences between lung parenchyma and surrounding tissue. These methods fail in scans where dense abnormalities are present, which often occurs in clinical data. Some methods to handle these situations have been proposed, but they are too time consuming or too specialized to be used in clinical practice. In this article, a new hybrid lung segmentation method is presented that automatically detects failures of a conventional algorithm and, when needed, resorts to a more complex algorithm, which is expected to produce better results in abnormal cases. In a large quantitative evaluation on a database of 150 scans from different sources, the hybrid method is shown to perform substantially better than a conventional approach at a relatively low increase in computational cost.

  3. In situ lung perfusion is a valuable tool to assess lungs from donation after circulatory death donors category I-II.

    PubMed

    Van De Wauwer, Caroline; Munneke, Anita J; Engels, Gerwin E; Berga, Foke M; Rakhorst, Gerhard; Nijsten, Maarten W; Mariani, Massimo A; Erasmus, Michiel E

    2013-05-01

    Donations after circulatory death (DCD) lung grafts are an alternative to extend the donor pool in lung transplantation. This study investigates the use of an in situ lung perfusion system (ISLP) in the donor to evaluate category I-II lungs. Pigs were sacrificed by ventricular fibrillation. All animals underwent 20 min of cardiopulmonary resuscitation and 5 min hands-off period after which heparin was administered. In group [WI-1], this was followed by 1 h of warm ischemia (WI) and 2 h of topical cooling (TC). In group [WI-2], 2 h of WI was followed by 1 h of TC. In group [WI-0], there was a minimal period of WI and no TC. In all three groups, the lungs were then evaluated during 60 min with ISLP. [WI-0] lungs showed a significantly higher compliance and Δ PO2 /FiO2 compared with [WI-1] and [WI-2]. PaCO2 and lactate production were higher in [WI-2] versus [WI-0]. Wet/Dry weight ratio was significantly higher in [WI-2] compared with [WI-0] in two lung biopsy locations. A high W/D weight ratio was correlated with a lower compliance, higher lactate production, and a higher PaCO2 . ISLP is an effective way to assess the quality of lungs from category I-II DCD donors. © 2013 The Authors Transplant International © 2013 European Society for Organ Transplantation. Published by Blackwell Publishing Ltd.

  4. Ex vivo rehabilitation of non-heart-beating donor lungs in preclinical porcine model: delayed perfusion results in superior lung function.

    PubMed

    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

    2012-11-01

    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 the potential for rehabilitation of donor lungs with extended warm ischemic times is unknown. The present study compared the efficacy of different treatment strategies for uncontrolled non-heart-beating donor lungs. Mature swine underwent hypoxic arrest, followed by 60 minutes of no-touch warm ischemia. The lungs were harvested and flushed with 4°C Perfadex. Three groups (n = 5/group) were stratified according to the preservation method: cold static preservation (CSP; 4 hours of 4°C storage), immediate EVLP (I-EVLP: 4 hours EVLP at 37°C), and delayed EVLP (D-EVLP; 4 hours of CSP followed by 4 hours of EVLP). The EVLP groups were perfused with Steen solution supplemented with heparin, methylprednisolone, cefazolin, and an adenosine 2A receptor agonist. The lungs then underwent allotransplantation and 4 hours of recipient reperfusion before allograft assessment for resultant ischemia-reperfusion injury. The donor blood oxygenation (partial pressure of oxygen/fraction of inspired oxygen ratio) before death was not different between the groups. The oxygenation after transplantation was significantly greater in the D-EVLP group than in the I-EVLP or CSP groups. The mean airway pressure, pulmonary artery pressure, and expression of interleukin-8, interleukin-1β, and tumor necrosis factor-α were all significantly reduced in the D-EVLP group. Post-transplant oxygenation exceeded the acceptable clinical levels only in the D-EVLP group. Uncontrolled non-heart-beating donor lungs with extended warm ischemia can be reconditioned for successful transplantation. The combination of CSP and EVLP in the D-EVLP group was necessary to obtain optimal post-transplant function. This finding, if confirmed clinically, will allow expanded use of nonheart-beating donor lungs. Copyright © 2012 The American Association for Thoracic

  5. 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

  6. A large substernal goiter as a cause of a pulmonary perfusion defect

    SciTech Connect

    Balon, H.R.; Meier, D.A. )

    1990-11-01

    A pulmonary perfusion defect was caused by an extremely large anterior mediastinal mass subsequently proved by I-131 imaging to be an intrathoracic extension of a cervical goiter. Substernal goiter is not known to be reported previously as one of the causes of a perfusion defect in lung scanning.

  7. Attenuated predictive power of a normal myocardial perfusion scan in young smokers.

    PubMed

    Wolak, Arik; Rafaeli, Einat; Toledano, Ronen; Novack, Victor; Gilutz, Harel; Henkin, Yaakov

    2014-06-01

    The negative predictive value of a normal myocardial perfusion image (MPI) for myocardial infarction or cardiac death is very high. However, it is unclear whether a normal MPI, reflecting non-compromised blood flow in the stable state, would have the same prognostic implications in smokers as in patients who do not smoke. The incidence of total mortality, cardiovascular mortality, and myocardial infarction was evaluated in 11,812 subjects (14.6% of whom were current smokers at the time of the study) with a normal MPI study and no past history of coronary artery disease during the period 1997 to 2008. During an average follow-up of 72.4 ± 32.4 months the risk for an acute myocardial infarction in current smokers was approximately 50% higher than the corresponding risk in non-smokers, despite a younger average age. Cox proportional regression models show that current smoking was associated with an increased hazard rate for the composite endpoint below age 60 (HR=2.09, 95%CI 1.43-3.07, p<0.001), but not at older ages (HR=1.16, 95% CI 0.81-1.66, p=0.4). In individuals below age 60, but not at older ages, current smoking is associated with increased short- and long-term risk of cardiac death and acute myocardial infarction even in subjects with a normal MPI. Copyright © 2014 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  8. Persisting perfusion defects after bronchoscopic removal or spontaneous expulsion of aspirated foreign objects.

    PubMed

    Kassner, E G; Solomon, N A; Steiner, P; Rao, M; Klotz, D H

    1976-10-01

    Follow-up lung scans were obtained in 9 children to determine whether perfusion lung scanning could be used to verify completeness of foreign-body removal. In 4 patients, extensive perfusion defects were present 4-19 days after removal of the object. In 1 patient, the area of hypoperfusion was larger than the territory served by a persistently obstructed lobar bronchus. Follow-up lung scans are of limited value for verifying completeness of foreign-body removal and localization of retained fragments.

  9. 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.

  10. Comparison of Biello, McNeil, and PIOPED criteria for the diagnosis of pulmonary emboli on lung scans.

    PubMed

    Webber, M M; Gomes, A S; Roe, D; La Fontaine, R L; Hawkins, R A

    1990-05-01

    The McNeil, Biello, and newly proposed PIOPED (from the National Institutes of Health-sponsored study, Prospective Investigation of Pulmonary Embolism Detection) interpretive methods for detection of pulmonary embolism on lung scans were compared in 96 patients who also underwent pulmonary angiography. Segmental findings on 99mTc perfusion and aerosol ventilation scans, chest radiographs, and pulmonary angiograms obtained within 48 hr of each other were encoded along with other information into a data base to facilitate analysis. The McNeil, Biello, and PIOPED criteria were applied to the encoded data. Although the PIOPED set of criteria yielded the most favorable likelihood ratio for predicting an angiogram showing pulmonary emboli and a favorable likelihood ratio for predicting an angiogram not showing pulmonary emboli, it had the highest number of indeterminate studies. The McNeil criteria demonstrated the least favorable likelihood for predicting pulmonary emboli on an angiogram. The Biello and McNeil criteria showed the most favorable likelihood ratio for predicting an angiogram not showing pulmonary emboli. Analysis of receiver-operating-characteristic (ROC) curves yielded the greatest area under the ROC curve for the Biello criteria, but there were no statistically significant differences among the three sets of criteria. This study suggests that the Biello scheme represents the best compromise of the sets of criteria studied.

  11. 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.

  12. Higher event rate in patients with known CAD despite a normal myocardial perfusion scan

    PubMed Central

    Fatima, Nosheen; Zaman, Unaiza; Zaman, Areeba; Balcoh, Dad J.; Rasheed, S Zahed

    2014-01-01

    Objective The negative predictive value of a normal single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is very high. However, prognostic implication of a normal SPECT MPI in patients with known coronary artery disease (CAD) is not clear. Objective of this study was to evaluate the cardiac event rate in patients with known CAD who had a normal stress SPECT MPI. Methods This prospective study accrued 428 consecutive patients with a history of CAD [revascularization or previous myocardial infarction (MI)] who had a normal stress (dynamic exercise or dipyridamole intervention) and rest Tc-99m-MIBI SPECT MPI. These patients were followed for 2-5 years (median: 3.1 years) for all-cause and cardiac mortality and non-fatal MI. Univariate and multivariate analyses were performed to identify predictors of outcome. Results During a follow-up period, all-cause mortality was found in 60 patients (14%) and 41 (10%) died of cardiac reasons. Non-fatal MI was found in 77 (18%) patients. Annualized cardiac mortality and non-fatal MI rates were 2% and 3.6% respectively. Smoking, congestive heart failure (CHF) and failure to achieve 85% age predicted heart rate were found to be predictors for all-cause and cardiac mortality. Diabetes, dyslipidemia, smoking and limited functional capacity (<7 METS) were found to be predictors for non-fatal MI. Conclusions Patients with known CAD had higher cardiac event rates despite a normal stress SPECT MPI. Diabetes, dyslipidemia, smoking and limited functional capacity were the predictors for fatal and non-fatal cardiac events. A cost effective but comprehensive surveillance strategy is warranted. PMID:25009792

  13. 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.

  14. 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

  15. Relative preservation of peripheral lung function in smoking-related pulmonary emphysema: assessment with 99mTc-MAA perfusion and dynamic 133Xe SPET.

    PubMed

    Suga, K; Kume, N; Matsunaga, N; Ogasawara, N; Motoyama, K; Hara, A; Matsumoto, T

    2000-07-01

    In this study the cross-sectional functional differences between the central and peripheral lung in smokers with pulmonary emphysema were evaluated by lung perfusion and dynamic xenon-133 single-photon emission tomography (SPET). The subjects were 81 patients with a long-term smoking history and relatively advanced emphysema, 17 non-smoker patients with non-obstructive lung diseases and six healthy non-smokers. Regional lung functional difference between the peripheral and central lung was assessed in the upper, middle and lower lung zones by technetium-99m macroaggregated albumin SPET and dynamic 133Xe SPET. The distribution of emphysematous changes was assessed by density-mask computed tomography (CT) images which depicted abnormally low attenuation areas (LAAs) of less than -960 Hounsfield units. Two hundred and eighty-eight (59.2%) lung zones of 63 (77.7%) patients with pulmonary emphysema showed relative preservation of lung function in the peripheral lung, with a curvilinear band of normal perfusion (a stripe sign) and a significantly faster 133Xe half-clearance time (T(1/2)) than in central lung (P<0.0001). Of these lung zones, 256 (88.8%) showed central-dominant LAA distributions on density-mask CT images, but the remaining 32 zones did not show any regional preference in LAA distribution. Conversely, 117 (24.0%) lung zones of 19 (23.4%) patients showed periphery-dominant perfusion defects and LAA distributions, with significantly prolonged T(1/2) in the peripheral lung area (P<0.0001). The remaining 81 lung zones of the patients with pulmonary emphysema and all the lung zones of the healthy subjects and patients with non-obstructive lung diseases did not show a stripe sign, and no differences were observed in T(1/2) values and LAA distributions between the central and peripheral lung. Relative preservation of peripheral lung function seems to be a characteristic feature in smoking-related pulmonary emphysema, and may indicate a lower susceptibility of

  16. The effect of pumpless extracorporeal CO2 removal on regional perfusion of the brain in experimental acute lung injury.

    PubMed

    Kreyer, Stefan; Muders, Thomas; Luepschen, Henning; Kricklies, Corinna; Linden, Katharina; Soehle, Martin; Zinserling, Joerg; Putensen, Christian; Wrigge, Hermann

    2013-07-01

    Lung-protective mechanical ventilation with low tidal volumes (V(T)) is often associated with hypercapnia (HC), which may be unacceptable in patients with brain injury. CO2 removal using a percutaneous extracorporeal lung assist (pECLA) enables normocapnia despite low V(T), but its effects on regional cerebral blood flow (rCBF) remain ambiguous. We hypothesized that reversal of HC by pECLA impairs rCBF in a porcine lung injury model. Lung injury was induced in 9 anesthetized pigs by hydrochloric acid aspiration. rCBF and systemic hemodynamics were measured by colored microsphere technique and transpulmonary-thermodilution during a randomized sequence of 4 experimental situations: pECLA shunt-on (1) with HC and (2) without HC, pECLA shunt-off (3) with HC and (4) without HC. HC increased rCBF (P<0.05). CO2 removal with pECLA resulting in normocapnia, decreased rCBF to levels comparable to those without pECLA and normocapnia. HC resulted in increased cardiac output (+25.5%). Cardiac output was highest during HC with pECLA shunt (+44.9%). During pECLA with CO2 removal, cardiac output (+38.1%) decreased compared with pECLA without CO2 removal, but stayed higher than during normocapnia/no pECLA shunt (P<0.05). In this animal model, mechanical ventilation with low V(T) was associated with HC and increased rCBF. CO2 removal by pECLA restored normocapnia, reduced rCBF to levels of normocapnia, but required a higher systemic blood flow for the perfusion of the pECLA device. If these results could be transferred to patients, extracorporeal CO2 removal might be an option for treatment of combined lung and brain injury in condition of a sufficient cardiac flow reserve.

  17. [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.

  18. Ventilation/perfusion SPECT or SPECT/CT for lung function imaging in patients with pulmonary emphysema?

    PubMed

    Froeling, Vera; Heimann, Uwe; Huebner, Ralf-Harto; Kroencke, Thomas J; Maurer, Martin H; Doellinger, Felix; Geisel, Dominik; Hamm, Bernd; Brenner, Winfried; Schreiter, Nils F

    2015-07-01

    To evaluate the utility of attenuation correction (AC) of V/P SPECT images for patients with pulmonary emphysema. Twenty-one patients (mean age 67.6 years) with pulmonary emphysema who underwent V/P SPECT/CT were included. AC/non-AC V/P SPECT images were compared visually and semiquantitatively. Visual comparison of AC/non-AC images was based on a 5-point likert scale. Semiquantitative comparison assessed absolute counts per lung (aCpLu) and lung lobe (aCpLo) for AC/non-AC images using software-based analysis; percentage counts (PC = (aCpLo/aCpLu) × 100) were calculated. Correlation between AC/non-AC V/P SPECT images was analyzed using Spearman's rho correlation coefficient; differences were tested for significance with the Wilcoxon rank sum test. Visual analysis revealed high conformity for AC and non-AC V/P SPECT images. Semiquantitative analysis of PC in AC/non-AC images had an excellent correlation and showed no significant differences in perfusion (ρ = 0.986) or ventilation (ρ = 0.979, p = 0.809) SPECT/CT images. AC of V/P SPECT images for lung lobe-based function imaging in patients with pulmonary emphysema do not improve visual or semiquantitative image analysis.

  19. (68) Ga-Ca-phytate particles: A potential lung perfusion agent of synthetic origin prepared in a cold kit format.

    PubMed

    Hsieh, William; Ali, Masood; Praehofer, Renee; Tsopelas, Chris

    2016-10-01

    The objective of this study was to investigate the radiosynthesis of (68) Ga-Ca-phytate particles and then characterize the formulation for radiochemical purity, radioactive particle size distribution, and biodistribution in normal rats. This radiotracer was prepared using a commercial phytate cold kit after reconstitution with saline, (68) Ga-chloride generator eluent, calcium chloride, and air, then heating at 100°C for 30 minutes to achieve 99% radiochemical purity of (68) Ga-particles that were 21% 3-5 μm, 8% 5-15 μm, and 71% >15 μm in diameter. This optimal formulation was stable for 2 hours at room temperature. Intravenous administration of (68) Ga-particles in rats resulted in an uptake of 93% in the lungs, 4% in the liver plus spleen, and 3% in the carcass after 20 minutes. Two-thirds of the carcass activity was radioactive blood, likely to be (68) Ga-transferrin. The positron emission tomography image was superior than the (99m) Tc-MAA image because it displayed high lung uptake against a low background. Low uptake by the liver, spleen did not interfere with the diagnostic quality, and faint activity in the submandibular (salivary) glands was due to (68) Ga-transferrin. The preclinical data so far indicate that (68) Ga-Ca-phytate particles have good potential as a lung perfusion imaging agent. Copyright © 2016 John Wiley & Sons, Ltd.

  20. More accurate quantification of pulmonary blood flow by magnetic resonance imaging than by lung perfusion scintigraphy in patients with fontan circulation.

    PubMed

    Fratz, Sohrab; Hess, John; Schwaiger, Markus; Martinoff, Stefan; Stern, Heiko C

    2002-09-17

    Quantitative evaluation of pulmonary perfusion using lung perfusion scintigraphy in patients with atriopulmonary anastomosis (APA) or total cavopulmonary connection (TCPC) or partial cavopulmonary connection (PCPC) is difficult because of preferential draining of the venae cavae to one lung. Scintigraphy is the gold standard. Phase-velocity MRI (PV-MRI) is a new technique for determining pulmonary perfusion. The aim of this study was therefore to determine whether PV-MRI is more accurate than scintigraphy for quantitative evaluation of pulmonary perfusion ratios in patients with APA, TCPC, or PCPC. We studied 15 patients with APA, TCPC, or PCPC (16+/-7 years old, 4 female). Twelve patients (15+/-8 years old, 3 female) with a single pulmonary blood source supplied by a subpulmonary ventricle, ensuring complete mixing of the radioactive tracer before entering the pulmonary circulation, served as controls. Pulmonary scintigraphy and PV-MRI were performed in all patients. Bland-Altman analysis showed a clinically unacceptable difference of 7.1% right pulmonary blood flow (27.2% upper and -13.0% lower limit of agreement) between the two methods in the study group. The two methods agreed excellently in the control group (difference, 1.6%; 4.0% upper and -7.2% lower limit of agreement), showing that the bad agreement in the study group was caused by the problems encountered using pulmonary scintigraphy in patients with APA, TCPC, or PCPC. Because of preferential caval flow into either lung, PV-MRI is more accurate for evaluating pulmonary perfusion ratios than lung perfusion scintigraphy in patients with Fontan-like circulation.

  1. Dual-energy snap-shot perfusion CT in suspect pulmonary nodules and masses and for lung cancer staging.

    PubMed

    Sudarski, Sonja; Hagelstein, Claudia; Weis, Meike; Schoenberg, Stefan O; Apfaltrer, Paul

    2015-12-01

    Dual energy computed tomography (DECT) has proven its clinical usefulness for improved tissue characterization within the past years. In thoracic oncology, DECT can be used to differentiate between benign and malignant pulmonary nodules and masses. In patients with known lung cancer, DECT can add incremental functional information to staging scans, therapeutic response evaluation, as well as to the assessment of lung function. This review aims to give an overview on the current clinical utilities of DECT of the chest, its multiple post-processing applications and dose saving options. Furthermore, this review highlights promising applications of DECT that merit implementation in future clinical routine.

  2. 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.

  3. Simulation-based validation and arrival-time correction for Patlak analyses of Perfusion-CT scans

    NASA Astrophysics Data System (ADS)

    Bredno, Jörg; Hom, Jason; Schneider, Thomas; Wintermark, Max

    2009-02-01

    Blood-brain-barrier (BBB) breakdown is a hypothesized mechanism for hemorrhagic transformation in acute stroke. The Patlak analysis of a Perfusion Computed Tomography (PCT) scan measures the BBB permeability, but the method yields higher estimates when applied to the first pass of the contrast bolus compared to a delayed phase. We present a numerical phantom that simulates vascular and parenchymal time-attenuation curves to determine the validity of permeability measurements obtained with different acquisition protocols. A network of tubes represents the major cerebral arteries ipsi- and contralateral to an ischemic event. These tubes branch off into smaller segments that represent capillary beds. Blood flow in the phantom is freely defined and simulated as non-Newtonian tubular flow. Diffusion of contrast in the vessels and permeation through vessel walls is part of the simulation. The phantom allows us to compare the results of a permeability measurement to the simulated vessel wall status. A Patlak analysis reliably detects areas with BBB breakdown for acquisitions of 240s duration, whereas results obtained from the first pass are biased in areas of reduced blood flow. Compensating for differences in contrast arrival times reduces this bias and gives good estimates of BBB permeability for PCT acquisitions of 90-150s duration.

  4. Guidelines for lung scintigraphy in children.

    PubMed

    Ciofetta, Gianclaudio; Piepsz, Amy; Roca, Isabel; Fisher, Sybille; Hahn, Klaus; Sixt, Rune; Biassoni, Lorenzo; De Palma, Diego; Zucchetta, Pietro

    2007-09-01

    The purpose of this set of guidelines is to help the nuclear medicine practitioner perform a good quality lung isotope scan. The indications for the test are summarised. The different radiopharmaceuticals used for the ventilation and the perfusion studies, the technique for their administration, the dosimetry, the acquisition of the images, the processing and the display of the images are discussed in detail. The issue of whether a perfusion-only lung scan is sufficient or whether a full ventilation-perfusion study is necessary is also addressed. The document contains a comprehensive list of references and some web site addresses which may be of further assistance.

  5. Noncontrast perfusion single-photon emission CT/CT scanning: a new test for the expedited, high-accuracy diagnosis of acute pulmonary embolism.

    PubMed

    Lu, Yang; Lorenzoni, Alice; Fox, Josef J; Rademaker, Jürgen; Vander Els, Nicholas; Grewal, Ravinder K; Strauss, H William; Schöder, Heiko

    2014-05-01

    Standard ventilation and perfusion (V˙/Q˙) scintigraphy uses planar images for the diagnosis of pulmonary embolism (PE). To evaluate whether tomographic imaging improves the diagnostic accuracy of the procedure, we compared noncontrast perfusion single-photon emission CT (Q˙-SPECT)/CT scans with planar V˙/Q˙scans in patients at high risk for PE. Between 2006 and 2010, most patients referred for diagnosis of PE underwent both Q˙-SPECT/CT scan and planar V˙/Q˙scintigraphy. All scans were reviewed retrospectively by four observers; planar scans were read with modified Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II and Prospective Investigative Study of Pulmonary Embolism Diagnosis (PISA-PED) criteria. On Q˙-SPECT/CT scan, any wedge-shaped peripheral perfusion defect occupying > 50% of a segment without corresponding pulmonary parenchymal or pleural disease was considered to show PE. The final diagnosis was established with a composite reference standard that included ECG, ultrasound of lower-extremity veins, D-dimer levels, CT pulmonary angiography (when available), and clinical follow-up for at least 3 months. One hundred six patients with cancer and mean Wells score of 4.4 had sufficient follow-up; 22 patients were given a final diagnosis of PE, and 84 patients were given a final diagnosis of no PE. According to PIOPED II, 13 studies were graded as intermediate probability. Sensitivity and specificity for PE were 50% and 98%, respectively, based on PIOPED II criteria; 86% and 93%, respectively, based on PISA-PED criteria; and 91% and 94%, respectively, based on Q˙-SPECT/CT scan. Seventy-six patients had additional relevant findings on the CT image of the Q˙-SPECT/CT scan. Noncontrast Q˙-SPECT/CT imaging has a higher accuracy than planar V˙/Q˙imaging based on PIOPED II criteria in patients with cancer and a high risk for PE.

  6. Lung hypoplasia in newborn rabbits with a diaphragmatic hernia affects pulmonary ventilation but not perfusion.

    PubMed

    Flemmer, Andreas W; Thio, Marta; Wallace, Megan J; Lee, Katie; Kitchen, Marcus J; Kerr, Lauren; Roehr, Charles C; Fouras, Andreas; Carnibella, Richard; Jani, Jaccques C; DeKoninck, Philip; Te Pas, Arjan B; Pearson, James T; Hooper, Stuart B

    2017-09-01

    BackgroundA congenital diaphragmatic hernia (DH) can result in severe lung hypoplasia that increases the risk of morbidity and mortality after birth; however, little is known about the cardiorespiratory transition at birth.MethodsUsing phase-contrast X-ray imaging and angiography, we examined the cardiorespiratory transition at birth in rabbit kittens with DHs. Surgery was performed on pregnant New Zealand white rabbits (n=18) at 25 days' gestation to induce a left-sided DH. Kittens were delivered at 30 days' gestation, intubated, and ventilated to achieve a tidal volume (Vt) of 8 ml/kg in control and 4 ml/kg in DH kittens while they were imaged.ResultsFunctional residual capacity (FRC) recruitment and Vt in the hypoplastic left lung were markedly reduced, resulting in a disproportionate distribution of FRC into the right lung. Following lung aeration, relative pulmonary blood flow (PBF) increased equally in both lungs, and the increase in pulmonary venous return was similar in both control and DH kittens.ConclusionThese findings indicate that nonuniform lung hypoplasia caused by DH alters the distribution of ventilation away from hypoplastic and into normally grown lung regions. During transition, the increase in PBF and pulmonary venous return, which is vital for maintaining cardiac output, is not affected by lung hypoplasia.

  7. Observation of Microvascular Perfusion in the Hegu (LI4) Acupoint Area after Deqi Acupuncture at Quchi (LI11) Acupoint Using Speckle Laser Blood Flow Scanning Technology.

    PubMed

    Huang, Tao; Yang, Li-Jian; Zhang, Wei-Bo; Jia, Shu-Yong; Tian, Yu-Ying; Wang, Guan-Jun; Mu, Xiang; Wang, Lu; Litscher, Gerhard

    2012-01-01

    The aim of this study was to investigate the traditional meridian theory using speckle laser blood flow scanning technology to observe microcirculation of the Hegu acupoint area after acupuncture stimulation on distant points. An observational study was conducted to observe the microvascular perfusion of Hegu (LI4) and control points after acupuncturing Quchi (LI11). Thirty healthy volunteers (mean age 31.6 ± 8.7 years) received deqi acupuncture on Quchi (LI11, right side), and simultaneously changes in microvascular perfusion of Sanjian (LI3), Hegu (LI4), Yangxi (LI5), and two control points were observed before, during, and after needling using a MOOR speckle laser. The results showed that the changes in microvascular perfusion of the observed points are not regular. After correction, the experiment showed that the blood perfusion on 3 meridian acupoints was increased while the perfusion on 2 control points was decreased following acupuncture stimulation, the changes at Hegu (LI4) being the statistically most significant ones. Deqi acupuncture can help in regulating the body's blood flow, with a certain degree of meridian specificity.

  8. Observation of Microvascular Perfusion in the Hegu (LI4) Acupoint Area after Deqi Acupuncture at Quchi (LI11) Acupoint Using Speckle Laser Blood Flow Scanning Technology

    PubMed Central

    Huang, Tao; Yang, Li-Jian; Zhang, Wei-Bo; Jia, Shu-Yong; Tian, Yu-Ying; Wang, Guan-Jun; Mu, Xiang; Wang, Lu; Litscher, Gerhard

    2012-01-01

    The aim of this study was to investigate the traditional meridian theory using speckle laser blood flow scanning technology to observe microcirculation of the Hegu acupoint area after acupuncture stimulation on distant points. An observational study was conducted to observe the microvascular perfusion of Hegu (LI4) and control points after acupuncturing Quchi (LI11). Thirty healthy volunteers (mean age 31.6 ± 8.7 years) received deqi acupuncture on Quchi (LI11, right side), and simultaneously changes in microvascular perfusion of Sanjian (LI3), Hegu (LI4), Yangxi (LI5), and two control points were observed before, during, and after needling using a MOOR speckle laser. The results showed that the changes in microvascular perfusion of the observed points are not regular. After correction, the experiment showed that the blood perfusion on 3 meridian acupoints was increased while the perfusion on 2 control points was decreased following acupuncture stimulation, the changes at Hegu (LI4) being the statistically most significant ones. Deqi acupuncture can help in regulating the body's blood flow, with a certain degree of meridian specificity. PMID:23258991

  9. Hepatocellular nodules in liver cirrhosis: state of the art CT evaluation (perfusion CT/volume helical shuttle scan/dual-energy CT, etc.).

    PubMed

    Okada, Masahiro; Kim, Tonsok; Murakami, Takamichi

    2011-06-01

    The purpose of this article is to explain the role of advanced liver CT imaging, including perfusion CT, dual-energy CT, and volume helical shuttle (VHS) scanning, with regard to its clinical applications. Perfusion CT is a promising method for calculating hepatic blood flow and portal blood flow, including microcirculation, using a color-encoded display of parameters obtained from the liver time-density curve, with iodine contrast agent. Tumor angiogenesis and assessment of the response to antiangiogenesis treatment (e.g., Sorafenib) can be analyzed by perfusion CT of the liver. VHS scan has very high temporal resolution due to the reciprocating movement employed during scanning, enabling the acquisition of 24 scans of the whole liver in the arterial dominant phase during a 40-s breath hold, and a reduction in radiation dose. Dual-energy CT enables differentiation of materials and tissues based on their CT density values, using two different energy spectra. This method includes a low tube voltage CT technique that increases the contrast enhancement of vascular structures while simultaneously reducing radiation dose. Images obtained at the preferred settings of low tube voltage and high tube current, with dose reduction in the hepatic arterial phase, are useful for detecting hypervascular hepatocellular carcinoma.

  10. Assessment of branch pulmonary artery stenosis in children after repair of tetralogy of Fallot using lung perfusion scintigraphy comparison with echocardiography.

    PubMed

    Chien, Kuang-Jen; Huang, Hurng-Wern; Huang, Ta-Cheng; Lee, Cheng-Liang; Weng, Ken-Pen; Lin, Chu-Chuan; Shieh, Po-Chuen; Wu, Ming-Ting; Hsieh, Kai-Sheng

    2016-01-01

    The aim of this study was to compare the usefulness of lung perfusion scintigraphy and echocardiogram in the evaluation of the branch pulmonary arteries stenosis in children with tetralogy of Fallot (TOF). From February 2006 to November 2008, 74 children (mean age 7.8 years, range 1–18 years) who underwent repair of TOF at ages from 10 months to 13 years were suspected to have unilateral or bilateral branch pulmonary artery stenosis. In all patients, cardiac angiography was performed to confirm the diagnosis of branch pulmonary artery stenosis. Lung perfusion scintigraphy and two-dimensional transthoracic echocardiography were performed in all patients to compare their abilities to diagnose branch pulmonary artery stenosis. Of the 74 patients, 51 cases were found to have branch pulmonary artery stenosis by cardiac angiography. There was agreement between the scintigraphic and angiographic findings in 44 (86%) patients and there were discrepancies in 11 (15%) patients. The positive predictive value of our lung perfusion scintigraphy in detecting the branch pulmonary artery stenosis was 92 %. The positive and negative likelihood ratios of lung perfusion scintigraphy were 4.96 and 0.17, respectively. There was conformity between the echocardiographic and angiographic findings in 40 (78%) patients with discrepancies in 16 (21%) patients. The positive predictive value of our echocardiography in detecting the branch pulmonary artery stenosis was 89%. The positive and negative likelihood ratios of echocardiography were 3.61 and 0.28, respectively. Lung perfusion scintigraphy is a valuable, non-invasive screening tool in the assessment of branch pulmonary artery stenosis in children after TOF.

  11. Axial segmentation of lungs CT scan images using canny method and morphological operation

    NASA Astrophysics Data System (ADS)

    Noviana, Rina; Febriani, Rasal, Isram; Lubis, Eva Utari Cintamurni

    2017-08-01

    Segmentation is a very important topic in digital image process. It is found simply in varied fields of image analysis, particularly within the medical imaging field. Axial segmentation of lungs CT scan is beneficial in designation of abnormalities and surgery planning. It will do to ascertain every section within the lungs. The results of the segmentation are accustomed discover the presence of nodules. The method which utilized in this analysis are image cropping, image binarization, Canny edge detection and morphological operation. Image cropping is done so as to separate the lungs areas, that is the region of interest. Binarization method generates a binary image that has 2 values with grey level, that is black and white (ROI), from another space of lungs CT scan image. Canny method used for the edge detection. Morphological operation is applied to smoothing the lungs edge. The segmentation methodology shows an honest result. It obtains an awfully smooth edge. Moreover, the image background can also be removed in order to get the main focus, the lungs.

  12. High-resolution CT scan findings in patients with symptomatic scleroderma-related interstitial lung disease.

    PubMed

    Goldin, Jonathan G; Lynch, David A; Strollo, Diane C; Suh, Robert D; Schraufnagel, Dean E; Clements, Philip J; Elashoff, Robert M; Furst, Daniel E; Vasunilashorn, Sarinnapha; McNitt-Gray, Michael F; Brown, Mathew S; Roth, Michael D; Tashkin, Donald P

    2008-08-01

    Lung disease has become the leading cause of mortality and morbidity in scleroderma (SSc) patients. The frequency, nature, and progression of interstitial lung disease seen on high-resolution CT (HRCT) scans in patients with diffuse SSc (dcSSc) compared with those with limited SSc (lcSSc) has not been well characterized. Baseline HRCT scan images of 162 participants randomized into a National Institutes of Health-funded clinical trial were compared to clinical features, pulmonary function test measures, and BAL fluid cellularity. The extent and distribution of interstitial lung disease HRCT findings, including pure ground-glass opacity (pGGO), pulmonary fibrosis (PF), and honeycomb cysts (HCs), were recorded in the upper, middle, and lower lung zones on baseline and follow-up CT scan studies. HRCT scan findings included 92.9% PF, 49.4% pGGO, and 37.2% HCs. There was a significantly higher incidence of HCs in the three zones in lcSSc patients compared to dcSSc patients (p = 0.034, p = 0.048, and p = 0.0007, respectively). The extent of PF seen on HRCT scans was significantly negatively correlated with FVC (r = - 0.22), diffusing capacity of the lung for carbon monoxide (r = - 0.44), and total lung capacity (r = - 0.36). A positive correlation was found between pGGO and the increased number of acute inflammatory cells found in BAL fluid (r = 0.28). In the placebo group, disease progression was assessed as 30% in the upper and middle lung zones, and 45% in the lower lung zones. No difference in the progression rate was seen between lcSSc and dcSSc patients. PF and GGO were the most common HRCT scan findings in symptomatic SSc patients. HCs were seen in more than one third of cases, being more common in lcSSc vs dcSSc. There was no relationship between progression and baseline PF extent or lcSSc vs dcSSc. Clinicaltrials.gov Identifier: NCT00004563.

  13. Ventilation-perfusion-chest radiography match is less likely to represent pulmonary embolism if perfusion is decreased rather than absent.

    PubMed

    Kim, C K; Worsley, D F; Alavi, A

    2000-09-01

    The authors' goal was to determine whether the prevalence of pulmonary embolism in patients with matching ventilation-perfusion (V-Q) defects and chest radiographic opacities differs depending on the degree of perfusion deficit (absent versus decreased). The authors performed a retrospective analysis of the data obtained from the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study. In 233 patients, angiograms were of diagnostic quality for 275 lung zones that showed matching V-Q defects and chest radiographic opacities (triple matches). Of these, V-Q scans and chest radiographs from 217 patients with triple matches in 255 lung zones were retrieved and reviewed. Areas corresponding to chest radiographic opacities were scored as having either decreased perfusion or absent perfusion by consensus. Information regarding the presence or absence of pulmonary embolism in corresponding lung zones was obtained from the PIOPED database. The overall prevalence of pulmonary embolism in all lung zones with triple matches was 27% (69 of 255). Of the 255 areas of triple matches, the perfusion was decreased in 153 (60%) and absent in 102 (40%). The prevalence of pulmonary embolism in areas of triple matches with decreased perfusion and triple matches with absent perfusion was 13% (20 of 153) and 48% (49 of 102), respectively (P = 0.0001 by the chi-square test). When these were divided further by lung zones, triple matches with decreased perfusion and triple matches with absent perfusion in the upper-middle lung zone were associated with a prevalence of 0% (O of 44), and 25% (9 of 36), respectively. The prevalence of pulmonary embolism in areas of triple matches with decreased perfusion and triple matches with absent perfusion in the lower lung zone was 18% (20 of 109), and 61% (40 of 66), respectively. A V-Q/chest radiographic match is less likely to represent pulmonary embolism if perfusion is decreased rather than absent. The overall prevalence of pulmonary

  14. Adaptive 4D volume perfusion CT of lung cancer: effects of computerized motion correction and the range of volume coverage on measurement reproducibility.

    PubMed

    Lee, Sang Min; Lee, Hyun-Ju; Kim, Jung Im; Kang, Mi-Jin; Goo, Jin Mo; Park, Chang Min; Im, Jung-Gi

    2013-06-01

    The purpose of this study was to determine whether measurement reproducibility can be improved using computerized motion correction and whole-tumor coverage in adaptive 4D perfusion CT of lung cancer. Perfusion CT covering the entire z-axis of a mass was performed of 40 patients with lung cancer. Each perfusion CT study was performed in 93.5 seconds and included 17 repeated dynamic CT scans obtained using the Adaptive 4D Spiral mode. Tumor blood flow (BF), blood volume (BV), and permeability were measured in four different manners: in the entire tumor (whole-tumor coverage) without the use of motion correction; in the entire tumor with motion correction; in a small volume of interest (VOI) of tumor without motion correction; and in a small VOI with motion correction. Intra- and interobserver reproducibility were assessed through Bland-Altman analyses. The 95% limits of intraobserver reproducibility for BF, BV, and permeability were as follows: -52.1% to 48.0%, -22.4% to 27.8%, and -33.2% to 38.5%, respectively, in the whole tumor without motion correction; -53.3% to 45.6%, -17.7% to 20.6%, and -31.5% to 37.0% in the whole tumor with motion correction; -107.8% to 97.4%, -98.3% to 93.7%, and -132.3% to 100.7% in a small VOI of tumor without motion correction; and -74.9% to 98.6%, -74.5% to 88.1%, and -109.8% to 114.1% in a small VOI with motion correction. The 95% limits of interobserver reproducibility for BF, BV, and permeability were as follows: -57.0% to 62.5%, -36.8% to 52.6%, and -47.7% to 66.0%, respectively, in the whole tumor without motion correction; -55.7% to 55.8%, -25.8% to 42.0%, and -35.3% to 46.7% in the whole tumor with motion correction; -146.6% to 165.1%, -117.1% to 137.7%, and -143.2% to 149.8% in a small VOI of tumor without motion correction; and -106.2% to 133.6%, -99.5% to 122.4%, and -108.6% to 170.0% in a small VOI of tumor with motion correction. Overall, the best reproducibility was obtained when measurements were obtained in the entire

  15. 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.

  16. Clinical outcomes of cytoreductive surgery combined with intrapleural perfusion of hyperthermic chemotherapy in advanced lung adenocarcinoma with pleural dissemination

    PubMed Central

    Yi, Eunjue; Kim, Daejoong; Cho, Sukki; Kim, Kwhanmien

    2016-01-01

    Background This study aimed to investigate the safety and feasibility of intrapleural perfusion hyperthermic chemotherapy (IPHC) followed by cytoreductive surgery as a part of multimodal strategy for the treatment of advanced lung adenocarcinoma. Methods Medical records of advanced lung cancer patients with pleural dissemination who underwent surgical treatment between 2003 and 2013 were reviewed retrospectively. Enrolled patients were divided into a surgery group comprising patients who underwent surgery only and an IPHC group, which consisted of patients who underwent surgery combined with IPHC. Results A total of 33 patients were enrolled in this study. Twenty-three patients underwent IPHC after surgical resection, and 10 patients underwent surgical resection only. The complication rate of the IPHC group was estimated to be 34.8% (8 cases), none of which included postoperative mortality. The complication rate of the surgery group was 40.0% (4 cases), which included one postoperative mortality. The 6-month, 1-year, and 3-year overall survival rates for the IPHC group were 95.7%, 91.3% and 38.6%, respectively, while those of the surgery group were 80.0%, 80.0% and 37.5%. The 6-month, 1-year and 3-year progression-free survival rates for the IPHC group were 87.0%, 47.8% and 24.3%, while those of surgery group were 44.4%, 33.3% and 0.0%, respectively. There were significant differences in overall survival rates between two groups (P=0.045); however, progression-free survival was not different between the two groups. Conclusions IPHC combined with cytoreductive surgery for advanced lung adenocarcinoma associated with pleural seeding could be performed safely and feasible. It would be part of multimodality therapy for certain category of advanced lung adenocarcinoma. However, the long-term benefits for survival is uncertain. More extensive and precisely designed studies are warranted to further evaluate the effectiveness of IPHC. PMID:27499943

  17. Insulin self-association: effects on lung disposition kinetics in the airways of the isolated perfused rat lung (IPRL).

    PubMed

    Pang, Yinuo; Sakagami, Masahiro; Byron, Peter R

    2007-09-01

    To characterize the kinetic dependence of pulmonary absorption and metabolism of insulin and lispro on the magnitude of their hexameric association. Hexamer content by weight percent (%Hex) in various insulin-zinc and lispro-zinc solutions were determined by quantitative centrifugal ultrafiltration and zinc titration with terpyridine (QCUF-ZTT). Each of the solutions (0.1 ml) was then administered into the airways of the IPRL of normal and experimental diabetic animals. Rate constants were determined for lung absorption (k (a)) and non-absorptive loss (k (nal); comprising mucociliary clearance and metabolism). %Hex in administered solutions ranged from 3.3 to 94.4%. Data analysis showed excellent correlations between the values for k (a) or k (nal) and %Hex, irrespective of insulin type, concentration, solution pH or ionic strength. The values for k (a) decreased (0.22 --> 0.05 h(-1)) with increasing %Hex, as did values for k (nal). At %Hex in administered solutions >/=50%, values for k (nal) approached estimates for the rate constant for mucociliary clearance, implying that lung metabolism occurred primarily with monomeric insulin. There were no differences in insulin disposition kinetics between lungs taken from experimental diabetic and sham-control animals. The kinetics of pulmonary insulin disposition depended on the magnitude of molecular self-association. Dissociated forms of insulin (dimers or monomers) in the dosing solution showed higher rates than hexamers for both lung absorption and metabolism.

  18. 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

    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

    2015-01-01

    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. 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 one 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 h 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. Each increase in the number of genetic modifications was associated with additional prolongation of lung xenograft survival. Lungs that exhibited survival to 4 h 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. 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 and pathway-specific injury and explore

  19. 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.

  20. Lung and leg scanning with 99mTc-labelled albumin macroaggregates

    PubMed Central

    Driedger, Albert A.; Reid, Brian D.; Heagy, Fred C.

    1974-01-01

    The routine injection of 99mTc-macroaggregated albumin into dorsal foot veins for lung scanning allows en passant assessment to be made regarding the presence of deep venous phlebitis. The radiopharmaceutical adhered to fibrin deposits in veins of calves and thighs in 103 of 386 examinations. In the 103 patients with a presumptive diagnosis of thrombophlebitis, microembolization from labelled thrombi, producing “hot spots” in the lungs, occurred in 25 cases. It is inferred that pulmonary microembolization is a very common event in patients with phlebitis. ImagesFIG. 1FIG. 2 PMID:4414524

  1. Automatic lung nodule matching for the follow-up in temporal chest CT scans

    NASA Astrophysics Data System (ADS)

    Hong, Helen; Lee, Jeongjin; Shin, Yeong Gil

    2006-03-01

    We propose a fast and robust registration method for matching lung nodules of temporal chest CT scans. Our method is composed of four stages. First, the lungs are extracted from chest CT scans by the automatic segmentation method. Second, the gross translational mismatch is corrected by the optimal cube registration. This initial registration does not require extracting any anatomical landmarks. Third, initial alignment is step by step refined by the iterative surface registration. To evaluate the distance measure between surface boundary points, a 3D distance map is generated by the narrow-band distance propagation, which drives fast and robust convergence to the optimal location. Fourth, nodule correspondences are established by the pairs with the smallest Euclidean distances. The results of pulmonary nodule alignment of twenty patients are reported on a per-center-of mass point basis using the average Euclidean distance (AED) error between corresponding nodules of initial and follow-up scans. The average AED error of twenty patients is significantly reduced to 4.7mm from 30.0mm by our registration. Experimental results show that our registration method aligns the lung nodules much faster than the conventional ones using a distance measure. Accurate and fast result of our method would be more useful for the radiologist's evaluation of pulmonary nodules on chest CT scans.

  2. 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

  3. 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

  4. Fluorescent human lung macrophages analyzed by spectral confocal laser scanning microscopy and multispectral cytometry.

    PubMed

    Pauly, John L; Allison, Erin M; Hurley, Edward L; Nwogu, Chukwumere E; Wallace, Paul K; Paszkiewicz, Geraldine M

    2005-06-01

    Numerous highly fluorescent macrophages (MPhi), designated "smoker cells," exist in the lungs of smokers and subjects who have quit smoking within 5 years. The brightly fluorescent MPhi, however, are not present in the lungs of never smokers. Some investigators have speculated that the intense fluorescence of the MPhi is due to smoke-induced changes in the autofluorescence of naturally occurring (i.e., endogenous) compounds (e.g., NADP). In contrast, other researchers have theorized that the fluorescence is due to the uptake of tobacco smoke particulates (i.e., "tar"). Studies reported herein were undertaken to test the hypothesis that the origin of the MPhi fluorescence could be profiled with the novel technologies afforded by spectral confocal laser scanning microscopy (sCLSM) and multispectral cytometry (MSC). To this end, spectral emissions were obtained by sCLSM of optical sections of live MPhi isolated from fresh surgically excised human lung tissue and in air-dried lung tissue imprints. Confirmation of spectral profiles of these single cell observations was obtained in population studies with the use of high-throughput MSC in which multispectral analyses were performed with three different lasers. Proof of concept experiments demonstrated that relatively nonfluorescent MPhi from the lungs of nonsmokers became fluorescent upon short-term ex vivo exposure to tobacco smoke tar. Summarily, the studies reported herein document that the fluorescence of human lung MPhi is due to tobacco tar. Copyright (c) 2005 Wiley-Liss, Inc.

  5. Assessment of differential pulmonary blood flow using perfusion magnetic resonance imaging: comparison with radionuclide perfusion scintigraphy.

    PubMed

    Molinari, Francesco; Fink, Christian; Risse, Frank; Tuengerthal, Siegfried; Bonomo, Lorenzo; Kauczor, Hans-Ulrich

    2006-08-01

    We sought to assess the agreement between lung perfusion ratios calculated from pulmonary perfusion magnetic resonance imaging (MRI) and those calculated from radionuclide (RN) perfusion scintigraphy. A retrospective analysis of MR and RN perfusion scans was conducted in 23 patients (mean age, 60 +/- 14 years) with different lung diseases (lung cancer = 15, chronic obstructive pulmonary disease = 4, cystic fibrosis = 2, and mesothelioma = 2). Pulmonary perfusion was assessed by a time-resolved contrast-enhanced 3D gradient-echo pulse sequence using parallel imaging and view sharing (TR = 1.9 milliseconds; TE = 0.8 milliseconds; parallel imaging acceleration factor = 2; partition thickness = 4 mm; matrix = 256 x 96; in-plane spatial resolution = 1.87 x 3.75 mm; scan time for each 3D dataset = 1.5 seconds), using gadolinium-based contrast agents (injection flow rate = 5 mL/s, dose = 0.1 mmol/kg of body weight). The peak concentration (PC) of the contrast agent bolus, the pulmonary blood flow (PBF), and blood volume (PBV) were computed from the signal-time curves of the lung. Left-to-right ratios of pulmonary perfusion were calculated from the MR parameters and RN counts. The agreement between these ratios was assessed for side prevalence (sign test) and quantitatively (Deming-regression). MR and RN ratios agreed on side prevalence in 21 patients (91%) with PC, in 20 (87%) with PBF, and in 17 (74%) with PBV. The MR estimations of left-to-right perfusion ratios correlated significantly with those of RN perfusion scans (P < 0.01). The correlation was higher using PC (r = 0.67) and PBF (r = 0.66) than using PBV (r = 0.50). The MR ratios computed from PBF showed the highest accuracy, followed by those from PC and PBV. Independently from the MR parameter used, in some patients the quantitative difference between the MR and RN ratios was not negligible. Pulmonary perfusion MRI can be used to assess the differential blood flow of the lung. Further studies in a larger group

  6. 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.

  7. 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.

  8. 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.

  9. Radiation-induced pulmonary arterial perfusion defects: modification by D-penicillamine. [Rats; /sup 60/Co

    SciTech Connect

    Ward, W.F.

    1981-04-01

    D-penicillamine, previously shown to have a beneficial effect on radiation-induced pulmonary histopathology, was tested to determine its effect on function in the irradiated lung. Male rats were irradiated with /sup 60/Co gamma rays; half then received 10 mg D-penicillamine per day, and half received no further treatment. One to nine months after irradiation, animals were subjected to lung perfusion scans. Untreated irradiated rats exhibited hyperemia, hypoperfusion, and perfusion defects of the irradiated lung. In penicillamine-treated rats, the appearance of perfusion defects was delayed, the peak incidence and severity of the defects was reduced, and recovery from pulmonary hypoperfusion was accelerated. Thus, using functional criteria, penicillamine appears to improve arterial perfusion and to ameliorate radiation injury in the rat lung.

  10. Determining the lymphadenopathy characteristics of the mediastinum in lung CT scan of children with tuberculosis.

    PubMed

    Mehrian, Payam; Moghaddam, Amin Momeni; Tavakkol, Elham; Amini, Afshin; Moghimi, Mehrdad; Kabir, Ali; Velayati, Aliakbar

    2016-09-01

    Most tuberculosis cases in children are primary infection, with difficult and imprecise diagnosis mainly based on the existence of mediastinal lymphadenopathy. Here, we investigated the characteristics of mediastinal lymphadenopathy in lung computed tomography (CT) scans of children with tuberculosis. This cross-sectional study was performed on 75 children with tuberculosis referred to Masih Daneshvari Hospital in Tehran, Iran, from 2009 to 2013. Their medical records were investigated, and CT-scan characteristics were extracted by a radiologist. Mean±standard deviation age of cases was 11.2±4.6years. CT-scan results indicated 94.7% of cases had lymphadenopathy, with lower paratracheal, upper paratracheal, hilar, and subcarinal forms observed in 81.7%, 69.1%, 53.5%, and 47.9% of cases as the most involved stations in lymph nodes, respectively. In 74.6% of patients with mediastinal lymphadenopathy, perilymph node fat inflammation (matting) was observed, with 52.11% exhibiting conglomeration. Bronchial pressure was observed in 4.23% of children with tuberculosis, and bilateral-, right-, and left-parenchymal involvement was observed in 42.7%, 25.3%, and 8% of these cases, respectively. Left- and right-pleural effusion and calcification was reported in 6.7%, 12%, and 5.6% of patients, respectively. Additionally, nearly 80% of patients exhibited mediastinal lymphadenopathy and lung-parenchyma involvement simultaneously. Lung-parenchyma involvement was significantly correlated with subcarinal (p<.001), hilar (p<.001), subaortic (p=.030), lower paratracheal (p=.037), and axillary (p=.006) stations. Situation of mediastinal lymphadenopathy and its synchronicity with lung-parenchyma involvement can help in differential diagnosis of pulmonary tuberculosis from other lung diseases. Copyright © 2016 Asian-African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.

  11. Analysis of Contrast-Enhanced Ultrasound Perfusion Patterns and Time-Intensity Curves for Metastatic Lymph Nodes From Lung Cancer: Preliminary Results.

    PubMed

    Yin, Shanshan; Cui, Qiuli; Wang, Song; Fan, Zhihui; Yan, Kun

    2017-09-06

    To retrospectively summarize the similarities and differences in contrast-enhanced ultrasound (US) findings for lymph node metastasis from adenocarcinoma, squamous carcinoma, and small cell lung cancer. Patients who had received contrast-enhanced US examinations and had a histologic diagnosis of supraclavicular lymph node metastasis from lung cancer were included. The perfusion patterns on contrast-enhanced US images and time-intensity curve parameters were analyzed for the different pathologic types. The microvascular density and microvascular diameter were evaluated. Totally, 61 patients were enrolled in this study, including 26 cases with lung squamous carcinoma, 26 with lung adenocarcinoma, and 9 with small cell lung cancer. Contrast-enhanced US perfusion showed no significant differences in enhancement uniformity during the arterial phase and in the presence of unenhanced areas of metastatic lymph nodes with the 3 different pathologic origins (P > .05), but fewer unenhanced areas could be seen in metastatic lymph nodes from adenocarcinoma. The analysis of the time-intensity curve parameters showed that there were significant differences in the peak intensity between metastatic lymph nodes from lung squamous carcinoma and lung adenocarcinoma (P < .05). The microvascular density of metastatic lymph nodes from adenocarcinoma was significantly higher than that of metastatic lymph nodes from squamous carcinoma and small cell lung cancer (P < .001; P = .0444), whereas the microvascular diameter of metastatic lymph nodes from adenocarcinoma was significantly smaller than that from squamous carcinoma and small cell lung cancer (P = .0277; P < .001). Effects of the pathologic diagnosis should be considered when analyzing quantitative parameters of metastatic lymph nodes during contrast-enhanced US examinations, even in the same organ. © 2017 by the American Institute of Ultrasound in Medicine.

  12. Regional ventilation/perfusion mismatch pattern in patient with Swyer James (MacLeod's) syndrome.

    PubMed

    Sager, Sait; Asa, Sertac; Akyel, Reşit; Atahan, Ersan; Kanmaz, Bedii

    2014-09-01

    Swyer James (McLeod's) syndrome (SJMS) is an uncommon disease, which occurs as a result of childhood bronchiolitis obliterans. Patients may not be diagnosed until later in their life. A 46-year-old man underwent ventilation/perfusion scintigraphy for acute onset of dyspnea. The scan showed markedly diminished ventilation and perfusion unilaterally on the right middle and inferior lobes. However, mismatched ventilation-perfusion pattern was shown on the upper right lobe, which was consistent with pulmonary embolism. Unilaterally matched ventilation/perfusion defect can see in SJMS in lung scintigraphy; however, when pulmoner embolism may accompany, scintigraphy should be carefully examined.

  13. Regional ventilation/perfusion mismatch pattern in patient with Swyer James (MacLeod's) syndrome

    PubMed Central

    Sager, Sait; Asa, Sertac; Akyel, Reşit; Atahan, Ersan; Kanmaz, Bedii

    2014-01-01

    Swyer James (McLeod's) syndrome (SJMS) is an uncommon disease, which occurs as a result of childhood bronchiolitis obliterans. Patients may not be diagnosed until later in their life. A 46-year-old man underwent ventilation/perfusion scintigraphy for acute onset of dyspnea. The scan showed markedly diminished ventilation and perfusion unilaterally on the right middle and inferior lobes. However, mismatched ventilation-perfusion pattern was shown on the upper right lobe, which was consistent with pulmonary embolism. Unilaterally matched ventilation/perfusion defect can see in SJMS in lung scintigraphy; however, when pulmoner embolism may accompany, scintigraphy should be carefully examined. PMID:25535507

  14. Location registration and recognition (LRR) for serial analysis of nodules in lung CT scans.

    PubMed

    Sofka, Michal; Stewart, Charles V

    2010-06-01

    In the clinical workflow for lung cancer management, the comparison of nodules between CT scans from subsequent visits by a patient is necessary for timely classification of pulmonary nodules into benign and malignant and for analyzing nodule growth and response to therapy. The algorithm described in this paper takes (a) two temporally-separated CT scans, I(1) and I(2), and (b) a series of nodule locations in I(1), and for each location it produces an affine transformation that maps the locations and their immediate neighborhoods from I(1) to I(2). It does this without deformable registration and without initialization by global affine registration. Requiring the nodule locations to be specified in only one volume provides the clinician more flexibility in investigating the condition of the lung. The algorithm uses a combination of feature extraction, indexing, refinement, and decision processes. Together, these processes essentially "recognize" the neighborhoods. We show on lung CT scans that our technique works at near interactive speed and that the median alignment error of 134 nodules is 1.70mm compared to the error 2.14mm of the Diffeomorphic Demons algorithm, and to the error 3.57mm of the global nodule registration with local refinement. We demonstrate on the alignment of 250 nodules, that the algorithm is robust to changes caused by cancer progression and differences in breathing states, scanning procedures, and patient positioning. Our algorithm may be used both for diagnosis and treatment monitoring of lung cancer. Because of the generic design of the algorithm, it might also be used in other applications that require fast and accurate mapping of regions.

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

    PubMed

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

    2013-06-01

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

  16. 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

  17. 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

  18. 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. Published by Elsevier Inc.

  19. Evaluation of residual functional lung volume on Tc-99m DTPA aerosol ventilation and Tc-99m MAA perfusion scintigraphy in primary ciliary dyskinesia (Kartagener syndrome).

    PubMed

    Chen, Yu-Wen; Chang, Chin-Chuan; Lai, Yung-Chuang; Lu, Chia-Ying; Dai, Zen-Kong

    2008-12-01

    Kartagener syndrome is diagnosed as sinusitis, bronchitis (bronchiectasis), and situs inversus by the clinical features. It is a subclass of primary ciliary dyskinesia (PCD) disease. A 12-year-old girl who had frequent upper and lower airway infections since birth, which was confirmed as Kartagener syndrome by HRCT imaging. We present the residual functional lung volume and mucociliary clearance findings seen on Tc-99m DTPA aerosol ventilation and Tc-99m MAA perfusion scintigraphy.

  20. The Impact of Sources of Variability on Parametric Response Mapping of Lung CT Scans.

    PubMed

    Boes, Jennifer L; Bule, Maria; Hoff, Benjamin A; Chamberlain, Ryan; Lynch, David A; Stojanovska, Jadranka; Martinez, Fernando J; Han, Meilan K; Kazerooni, Ella A; Ross, Brian D; Galbán, Craig J

    2015-09-01

    Parametric response mapping (PRM) of inspiration and expiration computed tomography (CT) images improves the radiological phenotyping of chronic obstructive pulmonary disease (COPD). PRM classifies individual voxels of lung parenchyma as normal, emphysematous, or nonemphysematous air trapping. In this study, bias and noise characteristics of the PRM methodology to CT and clinical procedures were evaluated to determine best practices for this quantitative technique. Twenty patients of varying COPD status with paired volumetric inspiration and expiration CT scans of the lungs were identified from the baseline COPD-Gene cohort. The impact of CT scanner manufacturer and reconstruction kernels were evaluated as potential sources of variability in PRM measurements along with simulations to quantify the impact of inspiration/expiration lung volume levels, misregistration, and image spacing on PRM measurements. Negligible variation in PRM metrics was observed when CT scanner type and reconstruction were consistent and inspiration/expiration lung volume levels were near target volumes. CT scanner Hounsfield unit drift occurred but remained difficult to ameliorate. Increasing levels of image misregistration and CT slice spacing were found to have a minor effect on PRM measurements. PRM-derived values were found to be most sensitive to lung volume levels and mismatched reconstruction kernels. As with other quantitative imaging techniques, reliable PRM measurements are attainable when consistent clinical and CT protocols are implemented.

  1. The Impact of Sources of Variability on Parametric Response Mapping of Lung CT Scans

    PubMed Central

    Boes, Jennifer L.; Bule, Maria; Hoff, Benjamin A.; Chamberlain, Ryan; Lynch, David A.; Stojanovska, Jadranka; Martinez, Fernando J.; Han, Meilan K.; Kazerooni, Ella A.; Ross, Brian D.; Galbán, Craig J.

    2015-01-01

    Parametric response mapping (PRM) of inspiration and expiration computed tomography (CT) images improves the radiological phenotyping of chronic obstructive pulmonary disease (COPD). PRM classifies individual voxels of lung parenchyma as normal, emphysematous, or nonemphysematous air trapping. In this study, bias and noise characteristics of the PRM methodology to CT and clinical procedures were evaluated to determine best practices for this quantitative technique. Twenty patients of varying COPD status with paired volumetric inspiration and expiration CT scans of the lungs were identified from the baseline COPD-Gene cohort. The impact of CT scanner manufacturer and reconstruction kernels were evaluated as potential sources of variability in PRM measurements along with simulations to quantify the impact of inspiration/expiration lung volume levels, misregistration, and image spacing on PRM measurements. Negligible variation in PRM metrics was observed when CT scanner type and reconstruction were consistent and inspiration/expiration lung volume levels were near target volumes. CT scanner Hounsfield unit drift occurred but remained difficult to ameliorate. Increasing levels of image misregistration and CT slice spacing were found to have a minor effect on PRM measurements. PRM-derived values were found to be most sensitive to lung volume levels and mismatched reconstruction kernels. As with other quantitative imaging techniques, reliable PRM measurements are attainable when consistent clinical and CT protocols are implemented. PMID:26568983

  2. 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.

  3. Segmentation of lung lesions on CT scans using watershed, active contours, and Markov random field

    PubMed Central

    Tan, Yongqiang; Schwartz, Lawrence H.; Zhao, Binsheng

    2013-01-01

    Purpose: Lung lesions vary considerably in size, density, and shape, and can attach to surrounding anatomic structures such as chest wall or mediastinum. Automatic segmentation of the lesions poses a challenge. This work communicates a new three-dimensional algorithm for the segmentation of a wide variety of lesions, ranging from tumors found in patients with advanced lung cancer to small nodules detected in lung cancer screening programs. Methods: The authors’ algorithm uniquely combines the image processing techniques of marker-controlled watershed, geometric active contours as well as Markov random field (MRF). The user of the algorithm manually selects a region of interest encompassing the lesion on a single slice and then the watershed method generates an initial surface of the lesion in three dimensions, which is refined by the active geometric contours. MRF improves the segmentation of ground glass opacity portions of part-solid lesions. The algorithm was tested on an anthropomorphic thorax phantom dataset and two publicly accessible clinical lung datasets. These clinical studies included a same-day repeat CT (prewalk and postwalk scans were performed within 15 min) dataset containing 32 lung lesions with one radiologist's delineated contours, and the first release of the Lung Image Database Consortium (LIDC) dataset containing 23 lung nodules with 6 radiologists’ delineated contours. The phantom dataset contained 22 phantom nodules of known volumes that were inserted in a phantom thorax. Results: For the prewalk scans of the same-day repeat CT dataset and the LIDC dataset, the mean overlap ratios of lesion volumes generated by the computer algorithm and the radiologist(s) were 69% and 65%, respectively. For the two repeat CT scans, the intra-class correlation coefficient (ICC) was 0.998, indicating high reliability of the algorithm. The mean relative difference was −3% for the phantom dataset. Conclusions: The performance of this new segmentation

  4. Lung texture in serial thoracic CT scans: Assessment of change introduced by image registration1

    PubMed Central

    Cunliffe, Alexandra R.; Al-Hallaq, Hania A.; Labby, Zacariah E.; Pelizzari, Charles A.; Straus, Christopher; Sensakovic, William F.; Ludwig, Michelle; Armato, Samuel G.

    2012-01-01

    Purpose: The aim of this study was to quantify the effect of four image registration methods on lung texture features extracted from serial computed tomography (CT) scans obtained from healthy human subjects. Methods: Two chest CT scans acquired at different time points were collected retrospectively for each of 27 patients. Following automated lung segmentation, each follow-up CT scan was registered to the baseline scan using four algorithms: (1) rigid, (2) affine, (3) B-splines deformable, and (4) demons deformable. The registration accuracy for each scan pair was evaluated by measuring the Euclidean distance between 150 identified landmarks. On average, 1432 spatially matched 32 × 32-pixel region-of-interest (ROI) pairs were automatically extracted from each scan pair. First-order, fractal, Fourier, Laws’ filter, and gray-level co-occurrence matrix texture features were calculated in each ROI, for a total of 140 features. Agreement between baseline and follow-up scan ROI feature values was assessed by Bland–Altman analysis for each feature; the range spanned by the 95% limits of agreement of feature value differences was calculated and normalized by the average feature value to obtain the normalized range of agreement (nRoA). Features with small nRoA were considered “registration-stable.” The normalized bias for each feature was calculated from the feature value differences between baseline and follow-up scans averaged across all ROIs in every patient. Because patients had “normal” chest CT scans, minimal change in texture feature values between scan pairs was anticipated, with the expectation of small bias and narrow limits of agreement. Results: Registration with demons reduced the Euclidean distance between landmarks such that only 9% of landmarks were separated by ≥1 mm, compared with rigid (98%), affine (95%), and B-splines (90%). Ninety-nine of the 140 (71%) features analyzed yielded nRoA > 50% for all registration methods, indicating that

  5. [Effect of hypocapnia/alkalosis on the fluid filtration rate in isolated and perfused rabbit lungs].

    PubMed

    Urich, Daniela; Trejo, Humberto; Pezzulo, Alejandro; Caraballo, Juan Carlos; Gutiérrez, Jeydith; Castro, Ignacio; Sánchez-de León, Roberto

    2008-06-01

    Hypocapnia/alkalosis is a consequence of several lung and metabolic pathologies. The aim of this study was to determine whether the increase of fluid filtration rate (FFR) that occurs during Hypocapnia/alkalosis circumstances is determined by hypocapnia, alkalosis or both. 7 groups were formed (N=36) using isolated rabbit lungs. Group 1: Control (PCO2 6%, pH: 7.35-7.45); Group 2 (n=6): Hypocapnia/Alkalosis (CO2 1%, pH: 7.9); Group 3 (n=6): Hypocapnia/Normo-pH (CO2 1% pH 7.35-7.45), Group 4 (n=6) Normocapnia/Alcalosis (CO2 6%, pH: 7.9). Fenoterol, papaverine and hydrocortisone were added to Groups 5, 6 and 7 (n=4) respectively, all under Normocapnia/Alkalosis. FFR and Pulmonary Arterial Pressure (Pap) were considerably higher in group 2 than in control (FFR: 1.92g/min +/- 0.6 vs 0.0 g/min +/- 0.006). A strong influence exerted by pH was observed when Group 3 and group 4 were compared (FFR: 0.02 g/min +/- 0.009 vs 2.3 g/min +/- 0.9) and (Pap: 13.5 cmH2O +/- 1.4 vs 90 cmH2O +/- 15). A reduced effect was observed in groups 5 and 6 (papaverine and hydrocorisone) and a totally abolished effect was observed in group 7 (fenoterol) (FFR: 0.001 +/- 0.0003 mL/min and Pap: 14 +/- 0.8 cmH2O). Pulmonary edema induced by Hypocapnia/alkalosis is a consequence of alkalosis and not of hypocapnia. This effect could be due to inflammatory damage in the lung parenchyma and alkalosis-mediated vasoconstriction.

  6. Whole-tumour CT-perfusion of unresectable lung cancer for the monitoring of anti-angiogenetic chemotherapy effects.

    PubMed

    Fraioli, F; Anzidei, M; Serra, G; Liberali, S; Fiorelli, A; Zaccagna, F; Longo, F; Anile, M; Catalano, C

    2013-09-01

    To determine whether CT-perfusion (CT-p) can be used to evaluate the effects of chemotherapy and anti-angiogenic treatment in patients with non-small-cell lung carcinoma (NSCLC) and whether CT-p and standard therapeutic response assessment (RECIST) data obtained before and after therapy correlate. 55 patients with unresectable NSCLC underwent CT-p before the beginning of therapy and 50 of them repeated CT-p 90 days after it. Therapeutic protocol included platinum-based doublets plus bevacizumab for non-squamous carcinoma and platinum-based doublets for squamous carcinoma. RECIST measurements and calculations of blood flow (BF), blood volume (BV), time to peak (TTP) and permeability surface (PS) were performed, and baseline and post-treatment measurements were tested for statistically significant differences. Baseline and follow-up perfusion parameters were also compared based on histopathological subclassification (2004 World Health Organization Classification of Tumours) and therapy response assessed by RECIST. Tumour histology was consistent with large cell carcinoma in 14/50 (28%) cases, adenocarcinoma in 22/50 (44%) cases and squamous cell carcinoma in the remaining 14/50 (28%) cases. BF and PS differences for all tumours between baseline and post-therapy measurements were significant (p=0.001); no significant changes were found for BV (p=0.3) and TTP (p=0.1). The highest increase of BV was demonstrated in adenocarcinoma (5.2±34.1%), whereas the highest increase of TTP was shown in large cell carcinoma (6.9±22.4%), and the highest decrease of PS was shown in squamous cell carcinoma (-21.5±18.5%). A significant difference between the three histological subtypes was demonstrated only for BV (p<0.007). On the basis of RECIST criteria, 8 (16%) patients were classified as partial response (PR), 2 (4%) as progressive disease (PD) and the remaining 40 (80%) as stable disease (SD). Among PR, a decrease of both BF (18±9.6%) and BV (12.6±9.2%) were observed; TTP

  7. Whole-tumour CT-perfusion of unresectable lung cancer for the monitoring of anti-angiogenetic chemotherapy effects

    PubMed Central

    Anzidei, M; Serra, G; Liberali, S; Fiorelli, A; Zaccagna, F; Longo, F; Anile, M; Catalano, C

    2013-01-01

    Objective: To determine whether CT-perfusion (CT-p) can be used to evaluate the effects of chemotherapy and anti-angiogenic treatment in patients with non-small-cell lung carcinoma (NSCLC) and whether CT-p and standard therapeutic response assessment (RECIST) data obtained before and after therapy correlate. Methods: 55 patients with unresectable NSCLC underwent CT-p before the beginning of therapy and 50 of them repeated CT-p 90 days after it. Therapeutic protocol included platinum-based doublets plus bevacizumab for non-squamous carcinoma and platinum-based doublets for squamous carcinoma. RECIST measurements and calculations of blood flow (BF), blood volume (BV), time to peak (TTP) and permeability surface (PS) were performed, and baseline and post-treatment measurements were tested for statistically significant differences. Baseline and follow-up perfusion parameters were also compared based on histopathological subclassification (2004 World Health Organization Classification of Tumours) and therapy response assessed by RECIST. Results: Tumour histology was consistent with large cell carcinoma in 14/50 (28%) cases, adenocarcinoma in 22/50 (44%) cases and squamous cell carcinoma in the remaining 14/50 (28%) cases. BF and PS differences for all tumours between baseline and post-therapy measurements were significant (p=0.001); no significant changes were found for BV (p=0.3) and TTP (p=0.1). The highest increase of BV was demonstrated in adenocarcinoma (5.2±34.1%), whereas the highest increase of TTP was shown in large cell carcinoma (6.9±22.4%), and the highest decrease of PS was shown in squamous cell carcinoma (−21.5±18.5%). A significant difference between the three histological subtypes was demonstrated only for BV (p<0.007). On the basis of RECIST criteria, 8 (16%) patients were classified as partial response (PR), 2 (4%) as progressive disease (PD) and the remaining 40 (80%) as stable disease (SD). Among PR, a decrease of both BF (18±9.6%) and BV (12

  8. 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.

  9. Evaluation of the preventive effect of dexpanthenol in radiation injury by lung perfusion scintigraphy: a preclinical experimental model of radiation injury.

    PubMed

    Koç, Zehra P; İn, Erdal; Karslioğlu, İhsan; Üçer, Özlem; Canpolat, Sinan

    2015-12-01

    The aim of this study was to show the preventative effects of dexpanthenol in radiation injuries caused by radiotherapy (RT) through the use of lung perfusion scintigraphy in the pre-RT and post-RT periods. Six male New Zealand rabbits (5-6 months of age and ∼2.5-3 kg in weight) were the used in this study. The animals were subjected to Tc-macroaggregated albumin lung perfusion scintigraphy in the pre-RT and post-RT (i.e. 2 weeks after treatment) periods. The scintigraphies were performed with the same dose by the same staff and the methodology used the same acquisition parameters. The rabbits were divided into two groups: group I (administered RT only) and group II (also administered intramuscular 500 mg dexpanthenol injections for 14 consecutive days after RT). Quantification was performed to compare the groups and the quantification variables were compared using a paired samples t-test, with P value less than 0.05 considered to be statistically significant. Histopathological analysis was also carried out. The post-RT scintigraphies indicated a decrease in the counts in both lungs, suggesting early post-RT injury. The difference between the counts obtained from both lungs in groups I and II was significantly different and favoured group II. Histopathological results confirmed the scintigraphy results. It is possible to estimate post-RT changes in the early period (in contrast to previous data) by lung perfusion scintigraphy. Dexpanthenol may also reduce the effects of RT to a degree. Although this is the first study to report the preventive effects of dexpanthenol on RT injuries, further studies are warranted in this area.

  10. Krypton-81m ventilation scanning: acute respiratory disease

    SciTech Connect

    Lavender, J.P.; Irving, H.; Armstrong, J.D. II

    1981-02-01

    From experience with 700 patients undergoing ventilation and perfusion lung scanning with krypton-81m/technetium-99m technique, 34 patients suffering from nonembolic acute respiratory disease were selected for review. In 16 patients with pneumonia, all had defects of ventilation corresponding to, or larger than, the radiologic consolidation. In 13 patients there was some preservation of perfusion in the consolidated region. In two of the three patients with matched defects, the pneumonia was of long standing. In seven patients with collapse or atelectasis and in 11 patients with acute reversible bronchial obstruction and normal volume lungs, a similar pattern or ventillation and perfusion was observed.

  11. [Lung cancer screening with low-dose thoracic CT-scan in the Somme area].

    PubMed

    Leleu, O; Auquier, M; Carre, O; Chauffert, B; Dubreuil, A; Petigny, V; Trancart, B; Berna, P; Jounieaux, V

    2017-03-01

    This feasibility trial proposes to set up in the department of the Somme an annual screening for lung cancer with low-dose thoracic CT. It responds to the first objective of the third cancer plan and follows the publication of the results of the National Lung Screening Trial in 2011. The method of this study is to use the existing networks among and between healthcare professionals and the departmental cancer screening structure. The inclusion criteria will be those of the National Lung Screening Trial. Screening will be proposed by treating physicians and chest physicians. The CT-scan will be performed in radiological centers that adhere to the good practice charter for low radiation scanning. A copy of CT results will be sent to the departmental structure of cancer screening (ADEMA80) which will ensure traceability and will perform statistical analysis. The study received funding from the Agence régionale de santé de la Picardie and la ligue contre le cancer. The primary endpoints of this screening will be the number of cancers diagnosed and the survival of the patients. The follow-up of positive examinations, delays in management and the level of participation will also be assessed. Copyright © 2016 SPLF. Published by Elsevier Masson SAS. All rights reserved.

  12. Computerized lung nodule detection on screening CT scans: performance on juxta-pleural and internal nodules

    NASA Astrophysics Data System (ADS)

    Sahiner, Berkman; Hadjiiski, Lubomir M.; Chan, Heang-Ping; Zhou, Chuan; Wei, Jun

    2006-03-01

    We are developing a computer-aided detection (CAD) system for lung nodules in thoracic CT volumes. Our CAD system includes an adaptive 3D pre-screening algorithm to segment suspicious objects, and a false-positive (FP) reduction stage to classify the segmented objects as true nodules or normal lung structures. We found that the effectiveness of the FP reduction stage was limited by the different characteristics of the objects in the internal and the juxta-pleural (JP) regions. The purpose of this study was to evaluate object characteristics in the internal and JP regions of a lung CT scan, and to develop different FP reduction classifiers for JP and internal objects. Our FP reduction technique utilized shape, grayscale, and gradient features, as well as the scores of a newly-developed neural network trained on the eigenvalues of the Hessian matrix in a volume of interest containing the suspicious object. We designed an algorithm to automatically label the objects as internal or JP. Based on a training set of 75 CT scans containing internal and JP nodules, two FP classifiers were trained separately for objects in the two types of lung regions. The system performance was evaluated on an independent test set of 27 low dose screening scans. An experienced chest radiologist identified 64 solid nodules (mean diameter: 5.3 mm, range: 3.0-12.9 mm) on the test cases, of which 33 were internal and 31 were JP. Our adaptive 3D prescreening algorithm detected 28 internal and 29 JP nodules. At 80% sensitivity, the average number of FPs was 3.9 and 9.7 in the internal and JP regions per scan, respectively. In comparison, a classifier designed to work on both types of nodules had an average of 29.4 FPs per scan at the same sensitivity. Our results indicate that it is more effective to use two different classifiers for JP and internal nodules because of their different characteristics. FPs in the JP region were more difficult to distinguish from true nodules. Further investigation

  13. Evaluation of optimized magnetic resonance perfusion imaging scanning time window after contrast agent injection for differentiating benign and malignant breast lesions.

    PubMed

    Dong, Jie; Wang, Dawei; Ma, Zhenshen; Deng, Guodong; Wang, Lanhua; Zhang, Jiandong

    2017-03-01

    The aim of the study was evaluate the 3.0 T magnetic resonance (MR) perfusion imaging scanning time window following contrast injection for differentiating benign and malignant breast lesions and to determine the optimum scanning time window for increased scanner usage efficiency and reduced diagnostic adverse risk factors. A total of 52 women with breast abnormalities were selected for conventional MR imaging and T1 dynamic-enhanced imaging. Quantitative parameters [volume transfer constant (Ktrans), rate constant (Kep) and extravascular extracellular volume fraction (Ve)] were calculated at phases 10, 20, 30, 40 and 50, which represented time windows at 5, 10, 15, 20 and 25 min, respectively, following injection of contrast agent. The association of the parameters at different phases with benign and malignant tumor diagnosis was analyzed. MR perfusion imaging was verified as an effective modality in the diagnosis of breast malignancies and the best scanning time window was identified: i) Values of Ktrans and Kep at all phases were statistically significant in differentiating benign and malignant tumors (P<0.05), while the value of Ve had statistical significance only at stage 10, but not at any other stages (P>0.05); ii) values of Ve in benign tumors increased with phase number, but achieved no obvious changes at different phases in malignant tumors; iii) the optimum scanning time window of breast perfusion imaging with 3.0 T MR was between phases 10 and 30 (i.e., between 5 and 15 min after contrast agent injection). The variation trend of Ve values at different phases may serve as a diagnostic reference for differentiating benign and malignant breast abnormalities. The most efficient scanning time window was indicated to be 5 min after contrast injection, based on the observation that the Ve value only had statistical significance in diagnosis at stage 10. However, the optimal scanning time window is from 5 to 15 min following the injection of contrast agent

  14. Comparison of lung scintigraphy with multi-slice spiral computed tomography in the diagnosis of pulmonary embolism.

    PubMed

    Wang, Feng; Fang, Wei; Lv, Bin; Lu, Jin-Guo; Xiong, Chang-Ming; Ni, Xin-Hai; He, Zuo-Xiang

    2009-07-01

    To compare the diagnostic efficacy of lung perfusion scans combined with ventilation (V/Q) scans and/or chest radiography (CR) with contrast-enhanced multislice spiral CT pulmonary angiography (CTPA) in diagnosing pulmonary embolism (PE). Eighty-two consecutive patients with suspected PE underwent CTPA, lung perfusion scan, and CR. Of them, 28 patients underwent V/Q scans. The final diagnosis was made using a composite reference test. The overall sensitivity and specificity were 89.2% and 92.1% for V/Q scan or perfusion scan combined with CR, and 97.3% and 97.4% for CTPA. For the 28 patients with V/Q scan, the sensitivity and specificity were 91.7% and 92.9% for V/Q scan, and 91.7% and 100.0% for CTPA. The segmental agreement rate between perfusion scan and CTPA was 69.5% (kappa = 0.30, P < 0.05). The perfusion scan revealed significantly more subsegmental abnormalities than CTPA (59 vs. 10, chi2 test, P < 0.05). V/Q scan, perfusion scan combined with CR and CTPA all show high efficacy in diagnosing PE. V/Q scan or perfusion scan combined with CR is as accurate as CTPA.

  15. Placental-site trophoblastic tumor with PET scan-detected surgically treated lung metastasis.

    PubMed

    Nieves, Lucybeth; Hoffman, James; Allen, Gretchen; Currie, John; Sorosky, Joel I

    2008-06-01

    Metastatic placental-site trophoblastic tumor (PSTT) continues to be a diagnostic and management dilemma due to its relative resistance to chemotherapy and the difficulties in diagnosing such a rare tumor. We describe a 35-year-old woman with PSTT presenting with irregular bleeding and a mass in the lung. Dilation and curettage provided the diagnosis of PSTT by frozen section of the specimen. Subsequently, a total abdominal hysterectomy was performed and the patient received three cycles of EMA-CO (etoposide, methotrexate, actinomycin D, cyclophosphamide, and vincristine) Positron emission tomography (PET) scan confirmed a persistent lung nodule that was treated with wedge resection. She is currently in clinical remission. Surgery may have a role in salvaging a patient with persistent PET-positive disease after chemotherapy.

  16. 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

  17. 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.

  18. Evaluation of (iodine-125)N,N,N'-trimethyl-N'-(2-hydroxy-3-methyl-5-iodobenzyl)-1,3- propanediamine lung uptake using an isolated-perfused lung model

    SciTech Connect

    Slosman, D.O.; Brill, A.B.; Polla, B.S.; Alderson, P.O.

    1987-02-01

    Lung uptake of N,N,N'-trimethyl-N'-(2-Hydroxy-3-methyl-5-iodobenzyl)-1,3- propanediamine (HIPDM) has been reported, but the mechanism of this process has not yet been established. Thus, single-pass (/sup 125/I)HIPDM accumulation was studied in rat lungs perfused with a Krebs-Ringer bicarbonate buffer containing 4.5% bovine albumin. Iodine-125 HIPDM lung accumulation was monitored by the percent of extraction per gram of lung tissue. Iodine-125 HIPDM lung uptake did not appear to occur by simple diffusion. As the time of perfusion was increased from 2 to 15 min, the rate of uptake of 2 microM (/sup 125/I)HIPDM decreased by 40%. During a 2-min perfusion, 98.6% +/- 6.7 (n = 8) extraction was observed with 2 microM (/sup 125/I)HIPDM, but only 38% +/- 2.0 (n = 3) was extracted when the (/sup 125/I)HIPDM concentration was 1 mM. The addition of 1 mM chlorpromazine, propranolol or imipramine also decreased (/sup 125/I)HIPDM lung uptake to 43.0% +/- 1.5, 51.4% +/- 2.2, and 49.8% +/- 0.8, respectively, (each n = 4 - 6, p less than 0.001). Cold (4 degrees C) had little effect on pulmonary accumulation (77.7% +/- 7.4, n = 5, p less than 0.01), and the addition of ouabain or the use of sodium-free medium had no effect. Thus, pulmonary (/sup 125/I)HIPDM accumulation does not appear to occur by sodium-dependent active transport. Rather, its uptake appears to be similar to the uptake of other basic amines, such as propranolol and imipramine, which are known to bind by physico-chemical interactions to pulmonary endothelial cell membranes and reflect pulmonary vascular surface area.

  19. Quality Improvement of Dual-Energy Lung Perfusion Image by Reduction of Low-Energy X-Ray Spectrum: An Evaluation on Clinical Images

    PubMed Central

    Kawai, Tatsuya; Ozawa, Yoshiyuki; Ogawa, Masaki; Ohashi, Kazuya; Suzuki, Kazushi; Shibamoto, Yuta

    2016-01-01

    Summary Background The effects of the reduction of low-energy X-ray spectrum on lung perfusion images created by dual-energy CT have not been well evaluated. The aim of this study is to investigate the reliability of lung perfusion blood volume (PBV) images created by dual-energy CT (DECT) equipped with or without a tin filter, focusing on its accuracy adjacent to high-attenuation areas. Material/Methods Among 176 patients who underwent DECT for suspicion of pulmonary embolism, 38 patients (mean age, 64; range, 16 to 83 years) without apparent evidence of pulmonary embolism were evaluated in this study. They underwent DECT at 100/140 kVp with a tin filter on 140 kVp tube (Group A; n=18) or at 80/140 kVp without the filter (Group B; n=20). On the lung PBV images, the degrees of artifacts – pulmonary enhancement defect (PED) and pseudo-enhancement in the trachea (PTE) adjacent to the vena cava were evaluated using a four-point scale (0=minimal to 3=prominent). Results The mean degrees of artifact in Group A were significantly lower than those in Group B (0.8 vs. 1.9; P<0.0001 for PED, respectively, and 1.1 vs. 2.2; P<0.0001 for TPE, respectively). The mean CTDIvols were 4.90±1.14 and 12.98±3.15 mGy (P<0.0001) for Group A and Group B, respectively. Conclusions The quality and accuracy of dual-energy lung perfusion image will be improved by using the tin filter technique. PMID:27994698

  20. Low-dose dynamic myocardial perfusion CT image reconstruction using pre-contrast normal-dose CT scan induced structure tensor total variation regularization

    NASA Astrophysics Data System (ADS)

    Gong, Changfei; Han, Ce; Gan, Guanghui; Deng, Zhenxiang; Zhou, Yongqiang; Yi, Jinling; Zheng, Xiaomin; Xie, Congying; Jin, Xiance

    2017-04-01

    Dynamic myocardial perfusion CT (DMP-CT) imaging provides quantitative functional information for diagnosis and risk stratification of coronary artery disease by calculating myocardial perfusion hemodynamic parameter (MPHP) maps. However, the level of radiation delivered by dynamic sequential scan protocol can be potentially high. The purpose of this work is to develop a pre-contrast normal-dose scan induced structure tensor total variation regularization based on the penalized weighted least-squares (PWLS) criteria to improve the image quality of DMP-CT with a low-mAs CT acquisition. For simplicity, the present approach was termed as ‘PWLS-ndiSTV’. Specifically, the ndiSTV regularization takes into account the spatial-temporal structure information of DMP-CT data and further exploits the higher order derivatives of the objective images to enhance denoising performance. Subsequently, an effective optimization algorithm based on the split-Bregman approach was adopted to minimize the associative objective function. Evaluations with modified dynamic XCAT phantom and preclinical porcine datasets have demonstrated that the proposed PWLS-ndiSTV approach can achieve promising gains over other existing approaches in terms of noise-induced artifacts mitigation, edge details preservation, and accurate MPHP maps calculation.

  1. 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.

  2. 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

  3. Assessment of Pre- and Post-Operative Cerebral Perfusion in Anterior Circulation Intracranial Aneurysm Clipping Patients at Hospital Sungai Buloh Using CT Perfusion Scan and Correlations to Fisher, Navarro and WFNS Scores.

    PubMed

    Ghani, Ailani Ab; Nayan, Saiful Azli Mat; Kandasamy, Regunath; Ghani, Abdul Rahman Izani; Rosman, Azmin Kass

    2017-02-01

    Intracranial aneurysms may rupture and are typically associated with high morbidity and mortality, commonly due to vasospasm after rupture. Once the aneurysm ruptures, the patient's cerebral blood flow may be disturbed during the acute phase, affecting cerebral circulation and thus cerebral perfusion prior to the onset of vasospasm. Fisher and Navarro scores are used to predict vasospasm, while World Federation of Neurosurgical Societies (WFNS) scores are used to predict patient outcomes. Several score modifications are available to obtain higher sensitivity and specificity for the prediction of vasospasm development, but these scores are still unsuccessful. Alternatively, cerebral CT perfusion scan (CTP) is a non-invasive method for measuring cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in regions of interests (ROI) to obtain the cerebral perfusion status as well as detecting vasospasm. A total of 30 patients' data with clipped anterior circulation intracranial aneurysms admitted to the hospital between 1 January 2013 and 30 June 2014, were collected from the hospital's electronic database. The data collected included patients' admissions demographic profiles, Fisher, Navarro and WFNS scores; and their immediate pre- and post-operative CTP parameters. This study found a significant increase in post-operative MTT (pre- and post-operative MTT) were 9.75 (SD = 1.31) and 10.44 (SD = 1.56) respectively, (P < 0.001)) as well as a significant reduction in post-operative CBF (pre- and post-operative mean CBF were 195.29 (SD = 24.92) and 179.49 (SD = 31.17) respectively (P < 0.001)). There were no significant differences in CBV. There were no significant correlations between the pre- and post-operative CTP parameters and Fisher, Navarro or WFNS scores. Despite the interest in using Fisher, Navarro and WFNS scores to predict vasospasm and patient outcomes for ruptured intracranial aneurysms, this study found no significant correlations

  4. Quantitative Computerized Two-Point Correlation Analysis of Lung CT Scans Correlates With Pulmonary Function in Pulmonary Sarcoidosis

    PubMed Central

    Erdal, Barbaros Selnur; Yildiz, Vedat; King, Mark A.; Patterson, Andrew T.; Knopp, Michael V.; Clymer, Bradley D.

    2012-01-01

    Background: Chest CT scans are commonly used to clinically assess disease severity in patients presenting with pulmonary sarcoidosis. Despite their ability to reliably detect subtle changes in lung disease, the utility of chest CT scans for guiding therapy is limited by the fact that image interpretation by radiologists is qualitative and highly variable. We sought to create a computerized CT image analysis tool that would provide quantitative and clinically relevant information. Methods: We established that a two-point correlation analysis approach reduced the background signal attendant to normal lung structures, such as blood vessels, airways, and lymphatics while highlighting diseased tissue. This approach was applied to multiple lung fields to generate an overall lung texture score (LTS) representing the quantity of diseased lung parenchyma. Using deidentified lung CT scan and pulmonary function test (PFT) data from The Ohio State University Medical Center’s Information Warehouse, we analyzed 71 consecutive CT scans from patients with sarcoidosis for whom simultaneous matching PFTs were available to determine whether the LTS correlated with standard PFT results. Results: We found a high correlation between LTS and FVC, total lung capacity, and diffusing capacity of the lung for carbon monoxide (P < .0001 for all comparisons). Moreover, LTS was equivalent to PFTs for the detection of active lung disease. The image analysis protocol was conducted quickly (< 1 min per study) on a standard laptop computer connected to a publicly available National Institutes of Health ImageJ toolkit. Conclusions: The two-point image analysis tool is highly practical and appears to reliably assess lung disease severity. We predict that this tool will be useful for clinical and research applications. PMID:22628487

  5. 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

  6. 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.

  7. Computerized lung nodule detection: comparison of performance for low-dose and standard-dose helical CT scans

    NASA Astrophysics Data System (ADS)

    Armato, Samuel G., III; Giger, Maryellen L.; Doi, Kunio; Bick, Ulrich; MacMahon, Heber

    2001-07-01

    The vast amount of image data acquired during a computed tomography (CT) scan makes lung nodule detection a burdensome task. Moreover, the growing acceptance of low-dose CT for lung cancer screening promises to further impact radiologists' workloads. Therefore, we have developed a computerized method to automatically analyze structures within a CT scan and identify those structures that represent lung nodules. Gray-level thresholding is performed to segment the lungs in each section to produce a segmented lung volume, which is then iteratively thresholded. At each iteration, remaining voxels are grouped into contiguous three-dimensional structures. Structures that satisfy a volume criterion then become nodule candidates. The set of nodule candidates is subjected to feature analysis. To distinguish candidates representing nodule and non-nodule structures, a rule-based approach is combined with an automated classifier. This method was applied to 43 standard-dose (diagnostic) CT scans and 13 low-dose CT scans. The method achieved an overall detection sensitivity of 71% with 1.5 false-positive detections per section on the standard-dose database and 71% sensitivity with 1.2 false-positive detections per section on the low-dose database. This automated method demonstrates promising performance in its ability to accurately detect lung nodules in standard-dose and low-dose CT images.

  8. (68)Ga-NOTA-CHSg and (99m)Tc-CHSg Labeled Microspheres for Lung Perfusion and Liver Radiomicrospheres Therapy Planning.

    PubMed

    Amor-Coarasa, Alejandro; Milera, Andrew; Carvajal, Denny; Gulec, Seza; Leichner, Jared; McGoron, Anthony J

    2013-01-01

    Fast biodegradable (12 h < half-life < 48 h) radioactive labeled microspheres are needed for PET and SPECT lung perfusion and radiomicrosphere therapy planning. An emulsion method was used to create 30.1 ±4.8  μ m size range microspheres with biodegradable Chitosan glycol (CHSg). Microspheres were characterized and labeled with (99m)Tc or (68)Ga as an alternative to MAA in perfusion PET and SPECT studies. Surface decoration of CHSg microspheres with p-SCN-Bn-NOTA was performed to increase (68)Ga  in vivo stability. (99m)Tc was labeled directly to the CHSg microspheres. Labeling yield and in vitro radiochemical stability were evaluated. In vitro CHSg microsphere degradation half-life was ~24 hours in porcine blood. Labeled microspheres were injected into Sprague Dawley rats and biodistribution was determined after 2 and 4 hours. Both (99m)Tc-CHSg and (68)Ga-NOTA-CHSg were quickly allocated in the lungs after injection. (99m)Tc-CHSg showed 91.6 ± 6.5% and 83.2 ± 4.1% of the decay corrected injected activity remaining in the lungs after 2 and 4 hours, respectively. For the obtained (68)Ga-NOTA-CHSg microspheres, lung allocation was very high with 98.9 ± 0.2% and 95.6 ± 0.9% after 2 and 4 hours, respectively. The addition of p-SCN-Bn-NOTA acts as a radioprotectant eliminating the released (68)Ga activity from the lungs to the bladder protecting the other organs.

  9. Effect of a patient-specific minimum activity in stress myocardial perfusion imaging using CZT-SPECT: Prognostic value, radiation dose, and scan outcome.

    PubMed

    van Dijk, J D; Borren, N M; Mouden, M; van Dalen, J A; Ottervanger, J P; Jager, P L

    2017-08-18

    SPECT Myocardial perfusion imaging (MPI) is associated with a relatively high radiation burden and decreasing image quality in heavy patients. Patient-specific low-activity protocols (PLAPs) are suggested but follow-up data is lacking. Our aim was to compare the use of a standard fixed-activity protocol (FAP) with a PLAP in cadmium zinc telluride (CZT)-SPECT MPI. We retrospectively included 1255 consecutive patients who underwent CZT-SPECT stress-optional rest MPI. 668 Patients were scanned using FAP (370 MBq) and 587 patients using PLAP (2.25 MBq·kg(-1)). Percentage of scans interpreted as normal, radiation dose, and 1-year follow-up including hard event rates (all-cause death or non-fatal myocardial infarction) were collected and compared. The percentage of scans interpreted as normal was 67% in FAP and 70% in PLAP groups (P = .29). The annualized hard event rates in these patients were 1.0% in the FAP and 0.9% in the PLAP group (P = .86). However, the mean radiation dose decreased by 23% for stress-only and by 15% to 2.6 mSv for stress-optional rest MPI after introduction of the PLAP (p<0.001). Introduction of a patient-specific low-activity protocol does not affect the percentage of scans interpreted as normal or prognosis but significantly lowers the radiation dose for CZT-SPECT MPI.

  10. Enhanced lung scan diagnosis of pulmonary embolism with the use of ancillary scintigraphic findings and clinical correlation.

    PubMed

    Freeman, L M; Krynyckyi, B; Zuckier, L S

    2001-04-01

    Analysis of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) and modified PIOPED studies has suggested that an experienced observer is capable of more accurate lung scan interpretation than the less experienced individual. This has been attributed to the use of unique Gestalt factors not contained in published diagnostic algorithms, which are acquired through extensive experience in reviewing and interpreting lung scans. How fully these factors can be codified and transmitted to less experienced observers is uncertain; however, there is a large body of published data that attempts to convey fine points of lung scan interpretation, including a large body of ancillary scintigraphic findings and a number of refinements in the application of diagnostic algorithms. Review of these factors will accelerate the training of less experienced readers. Finally, an understanding of lung scan language and an appreciation of clinically relevant factors, particularly pretest probability, will maximize the reader's ability to use the lung scan in managing patients who are suspected of having pulmonary embolic disease.

  11. Suspected pulmonary embolism and lung scan interpretation: Trial of a Bayesian reporting method

    SciTech Connect

    Becker, D.M.; Philbrick, J.T.; Schoonover, F.W.; Teates, C.D. )

    1990-07-01

    The objective of this research is to determine whether a Bayesian method of lung scan (LS) reporting could influence the management of patients with suspected pulmonary embolism (PE). The study is performed by the following: (1) A descriptive study of the diagnostic process for suspected PE using the new reporting method; (2) a non-experimental evaluation of the reporting method comparing prospective patients and historical controls; and (3) a survey of physicians' reactions to the reporting innovation. Of 148 consecutive patients enrolled at the time of LS, 129 were completely evaluated; 75 patients scanned the previous year served as controls. The LS results of patients with suspected PE were reported as posttest probabilities of PE calculated from physician-provided pretest probabilities and the likelihood ratios for PE of LS interpretations. Despite the Bayesian intervention, the confirmation or exclusion of PE was often based on inconclusive evidence. PE was considered by the clinician to be ruled out in 98% of patients with posttest probabilities less than 25% and ruled in for 95% of patients with posttest probabilities greater than 75%. Prospective patients and historical controls were similar in terms of tests ordered after the LS (e.g., pulmonary angiography). Patients with intermediate or indeterminate lung scan results had the highest proportion of subsequent testing. Most physicians (80%) found the reporting innovation to be helpful, either because it confirmed clinical judgement (94 cases) or because it led to additional testing (7 cases). Despite the probabilistic guidance provided by the study, the diagnosis of PE was often neither clearly established nor excluded. While physicians appreciated the innovation and were not confused by the terminology, their clinical decision making was not clearly enhanced.

  12. Suspected pulmonary embolism and lung scan interpretation: trial of a Bayesian reporting method.

    PubMed

    Becker, D M; Philbrick, J T; Schoonover, F W; Teates, C D

    1990-01-01

    To determine whether a Bayesian method of lung scan (LS) reporting could influence the management of patients with suspected pulmonary embolism (PE). 1) A descriptive study of the diagnostic process for suspected PE using the new reporting method; 2) a non-experimental evaluation of the reporting method comparing prospective patients and historical controls; and 3) a survey of physicians' reactions to the reporting innovation. University of Virginia Hospital. Of 148 consecutive patients enrolled at the time of LS, 129 were completely evaluated; 75 patients scanned the previous year served as controls. The LS results of patients with suspected PE were reported as posttest probabilities of PE calculated from physician-provided pretest probabilities and the likelihood ratios for PE of LS interpretations. Despite the Bayesian intervention, the confirmation or exclusion of PE was often based on inconclusive evidence. PE was considered by the clinician to be ruled out in 98% of patients with posttest probabilities less than 25% and ruled in for 95% of patients with posttest probabilities greater than 75%. Prospective patients and historical controls were similar in terms of tests ordered after the LS (e.g., pulmonary angiography). Patients with intermediate or indeterminate lung scan results had the highest proportion of subsequent testing. Most physicians (80%) found the reporting innovation to be helpful, either because it confirmed clinical judgement (94 cases) or because it led to additional testing (7 cases). Despite the probabilistic guidance provided by the study, the diagnosis of PE was often neither clearly established nor excluded. While physicians appreciated the innovation and were not confused by the terminology, their clinical decision making was not clearly enhanced.

  13. 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.

  14. Effects of thermal degradation products from polyurethane foams based on toluene diisocyanate and diphenylmethane diisocyanate on isolated, perfused lung of guinea pig.

    PubMed

    Låstbom, Lena; Colmsjö, Anders; Johansson, Rolf; Karlsson, Daniel; Melin, Jens; Nordqvist, Yvonne; Skarping, Gunnar

    2003-04-01

    The composition of thermal degradation products from two types of polyurethane foams, one based on toluene diisocyanate (TDI) and the other on diphenylmethane diisocyanate (MDI), was analyzed and their toxic lung effects were compared. Isolated perfused lungs of guinea pig were subjected to thermal decomposition products of polyurethane foams from an aerosol generator with compartments for diluting, mixing, and sampling. Thermal degradation of MDI-based polyurethane foams released MDI, phenyl isocyanate, and methyl isocyanate. The emitted particulate fraction was 75% for MDI, whereas that for TDI from TDI-based polyurethane foam was 3%. Thermal degradation products from MDI-based foam caused a pronounced dose-dependent decrease in the measured lung function parameters (conductance and compliance). In contrast, the thermal degradation products from TDI-based foam did not cause any decrease in lung function. Thermal degradation products generated from MDI-based polyurethane foam were more toxic to the lung than those generated from TDI-based polyurethane foam. This difference was probable due to MDI in the particle phase.

  15. Assessment of the intrapulmonary ventilation-perfusion distribution after the Fontan procedure for complex cardiac anomalies: Relation to pulmonary hemodynamics

    SciTech Connect

    Matsushita, T.; Matsuda, H.; Ogawa, M.; Ohno, K.; Sano, T.; Nakano, S.; Shimazaki, Y.; Nakahara, K.; Arisawa, J.; Kozuka, T. )

    1990-03-15

    In 12 patients who underwent the Fontan procedure for complex cardiac anomalies, lung scanning with xenon-133 was performed to assess the intrapulmonary ventilation-perfusion distribution, and comparison was made with a control group. All data were then analyzed in relation to either pre- or postoperative pulmonary hemodynamic data. In ventilation scans, the intrapulmonary distribution in the right lung was almost normal. In perfusion scans, an abnormal increased upper to lower lobe perfusion ratio greater than the normal value found in the control group was noted in seven patients (58.3%). There was a significant correlation (p less than 0.02) between the upper to lower lobe perfusion ratio and postoperative pulmonary vascular resistance. Furthermore, this perfusion ratio correlated inversely with the preoperative (p less than 0.005) and postoperative (p less than 0.02) right pulmonary artery area index, defined as the ratio of cross-sectional area to the normal value. Of five patients with less than 90% arterial oxygen saturation, four showed an abnormal distribution of pulmonary blood flow greater than the normal perfusion ratio. No patient had evidence of a pulmonary arteriovenous fistula by the echocardiographic contrast study. These results suggest that abnormal distribution of pulmonary blood flow to the upper lung segment may develop in patients after the Fontan procedure, and that insufficient size of the pulmonary artery before operation and the consequent postoperative elevation of pulmonary vascular resistance may be responsible for this perfusion abnormality.

  16. Ventilation/Perfusion SPECT lung scintigraphy and computed tomography pulmonary angiography in patients with clinical suspicion of pulmonary embolism.

    PubMed

    Ibáñez-Bravo, S; Banzo, I; Quirce, R; Martínez-Rodríguez, I; Jiménez-Bonilla, J; Martínez-Amador, N; Parra, J A; González-Macías, J; Carril, J M

    2016-01-01

    The aim was to compare ventilation/perfusion SPECT lung scintigraphy (V/Q-SPECT) and computed tomography pulmonary angiography (CTPA) in patients with suspicion of pulmonary embolism (PE). This prospectively designed study included 53 patients with intermediate or high clinical probability of PE. A V/Q-SPECT and CTPA was performed on all patients. The V/Q-SPECT was interpreted according to the European Association of Nuclear Medicine and Molecular Imaging (EANMMI) guidelines. CTPA was reported as positive, negative, or indeterminate. CTPA was positive in 22 cases, negative in 28, and indeterminate in 3. V/Q-SPECT was positive in 27 cases, negative in 24, and non-diagnostic in 2. In the 22 with positive CTPA, V/Q-SPECT was positive in 18, negative in 3, and non-diagnostic in 1. In the 28 with negative CTPA, V/Q-SPECT was positive in 8, negative in 19, and non-diagnostic in 1. In the 3 with indeterminate CTPA, V/Q-SPECT was positive in 1 and negative in 2. In the 2 non-diagnostic cases V/Q-SPECT, CTPA was positive in 1 and negative in one. In the 10 high clinical probabilities, CTPA and V/Q-SPECT were positive in 7, negative in 2, and in 1, CTPA was positive and V/Q-SPECT negative. In the 38 intermediate probability group, CTPA and V/Q-SPECT were positive in 11, negative in 17, with CTPA negative and V/Q-SPECT positive in 8, and in 2 CTPA was positive and V/Q-SPECT negative. The results show that V/Q-SPECT detected PE in 5 patients more than CTPA. Our results show a 77% concordance of both techniques. Overall V/Q-SPECT detected PE in 18% more patients than CTPA in the intermediate group. Both techniques have a complementary role when a diagnosis cannot be made with one of them. Copyright © 2016 Elsevier España, S.L.U. and SEMNIM. All rights reserved.

  17. 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

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

    PubMed

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

    2013-03-01

    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. 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 (PCRL) and phase-controlled volumetric rescanning (PCRV) were compared. 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×PCRL and 1×PCRV) degraded dose conformity significantly due to a reduced scan velocity. In contrast, 4×PCRL or more significantly and consistently improved dose distribution. PCRV showed interference effects, but in general also improved dose homogeneity with higher numbers of rescannings. Dose distributions with single PCRL∕PCRV with a

  19. Gallium lung scanning and bronchoalveolar lavage in crocidolite-exposed workers

    SciTech Connect

    Hayes, A.A.; Mullan, B.; Lovegrove, F.T.; Rose, A.H.; Musk, A.W.; Robinson, B.W.

    1989-07-01

    Gallium lung scanning is widely used to evaluate pulmonary inflammation in patients with interstitial lung disease but has not previously been reported in crocidolite-exposed workers. In order to characterize the pulmonary inflammation caused by crocidolite inhalation, GLS and BAL findings were related to chest x-ray film changes graded according to the ILO classification of roentgenograms of pneumoconioses. In individuals with roentgenographic evidence of asbestosis (CXR greater than or equal to 1/0, n = 15), 13 had a positive GLS and 13 had an abnormal BAL. In asbestos-exposed individuals with equivocal chest x-ray film changes (CXR 0/1, n = 12), six had a positive GLS and six had BAL changes (both GLS and BAL abnormal in three). In individuals with a normal chest x-ray film (CXR 0/0 n = 8), two had a positive GLS and two BAL changes (both abnormal in 1). These data demonstrate that most subjects with crocidolite-induced asbestosis have an abnormal GLS and BAL. In addition, many individuals with asbestos exposure and equivocal or no chest x-ray film changes have an abnormal GLS and/or BAL, suggesting the presence of active subclinical pulmonary inflammation in these individuals.

  20. 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

  1. Association Between Airway Caliber Changes With Lung Inflation and Emphysema Assessed by Volumetric CT Scan in Subjects With COPD

    PubMed Central

    Come, Carolyn E.; Ross, James C.; San José Estépar, Raúl; Han, MeiLan K.; Loring, Stephen H.; Silverman, Edwin K.; Washko, George R.

    2012-01-01

    Background: An increase in airway caliber (airway distensibility) with lung inflation is attenuated in COPD. Furthermore, some subjects have a decrease in airway caliber with lung inflation. We aimed to test the hypothesis that airway caliber increases are lower in subjects with emphysema-predominant (EP) compared with airway-predominant (AP) CT scan subtypes. Additionally, we compared clinical and CT scan features of subjects with (airway constrictors) and without a decrease in airway caliber. Methods: Based on GOLD (Global Initiative for Chronic Obstructive Lung Disease) stages and CT scan subtypes, we created a control group (n = 46) and the following matched COPD groups (n = 23 each): GOLD-2-AP, GOLD-2-EP, GOLD-4-AP, and GOLD-4-EP. From the CT scans of all 138 subjects, we measured emphysema, lung volumes, and caliber changes in the third and fourth airway generations of two bronchi. We expressed airway distensibility (ratio of airway lumen diameter change to lung volume change from end tidal breathing to full inspiration) as a global or lobar measure based on normalization by whole-lung or lobar volume changes. Results: Global distensibility in the third and fourth airway generations was significantly lower in the GOLD-2-EP and GOLD-4-EP groups than in control subjects. In GOLD-2 subjects, lobar distensibility of the right-upper-lobe fourth airway generation was significantly lower in those with EP than in those with AP. In multivariate analysis, emphysema was an independent determinant of global and lobar airway distensibility. Compared with nonconstrictors, airway constrictors experienced more dyspnea, were more hyperinflated, and had a higher percentage of emphysema. Conclusions: Distensibility of large- to medium-sized airways is reduced in subjects with an EP CT scan subtype. Emphysema seems to alter airway-parenchyma interdependence. Trial registry: ClinicalTrials.gov; No.: NCT00608764; URL: www.clinicaltrials.gov PMID:21940776

  2. 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

  3. 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.

  4. 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.

  5. 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

  6. [Effect of changes in airway pressure and the inspiratory volume on the fluid filtration rate and pulmonary artery pressure in isolated rabbit lungs perfused with blood and acellular solution].

    PubMed

    Crespo, Astrid; Novoa, Eva; Urich, Daniela; Trejo, Humberto; Pezzulo, Alejandro; Sznajder, Jacob I; Livia, Fernández; Sánchez-de León, Roberto

    2006-12-01

    It has been reported that ventilation with large tidal volumes causes pulmonary edema in rats by the stimulation and release of proinflammatory mediators. Our objective was to determine the level at which volutrauma induced by changes in Airway Pressure (PAW) and Inspiratory Volume (VI) produce significant changes on the Fluid Filtration Rate (FFR) and Pulmonary Artery Pressure (PAP) in lungs perfused with blood (cellular groups) or with a buffer-albumin solution (acellular groups), with a Positive End Expiratory Pressure (PEEP) 0 or 2 cmH2O and to study the effect of a vasodilator with antiinflammatory properties (fenoterol) in blood-perfused groups. Three experimental groups were used: the cellular groups studied the effect of increased PAW and IV in isolated lungs perfused with blood and PEEP 0 and 2; the acellular groups studied the increased PAW and IV in isolated lungs perfused with a buffer-albumin solution and PEEP 0 and 2; The fenoterol group studied the effect of increased PAW and IV in isolated lungs perfused with blood + fenoterol and PEEP 2. The results show that an increase of FFR is produced earlier in acellular groups than in cellular ones and that the damage in cellular groups is microscopically and macroscopically inferior when compared to acellular groups. Fenoterol did not inhibit edema formation, and that PEEP 2, both in the cellular and the acellular groups, has a protective effect. We propose the possible existence of mediators with protective effects against the formation of pulmonary edema in the blood. These data suggest that volutrauma induced pulmonary edema has a predominantly traumatic origin when the lungs are perfused with blood.

  7. Comparison of 133 xenon ventilation equilibrium scan (XV) and 99m technetium transmission (TT) scan for use in regional lung analysis by 2D gamma scintigraphy in healthy and cystic fibrosis lungs.

    PubMed

    Zeman, Kirby L; Wu, Jihong; Donaldson, Scott H; Bennett, William D

    2013-04-01

    Quantification of particle deposition in the lung by gamma scintigraphy requires a reference image for location of regions of interest (ROIs) and normalization to lung thickness. In various laboratories, the reference image is made by a transmission scan ((57)Co or (99m)Tc) or gas ventilation scan ((133)Xe or (81)Kr). There has not been a direct comparison of measures from the two methods. We compared (99m)Tc transmission scans to (133)Xe equilibrium ventilation scans as reference images for 38 healthy subjects and 14 cystic fibrosis (CF) patients for their effects on measures of regional particle deposition: the central-to-peripheral ratio of lung counts (C/P); and ROI area versus forced vital capacity. Whole right lung ROI was based on either an isocontour threshold of three times the soft tissue transmission (TT) or a threshold of 20% of peak xenon ventilation counts (XV). We used a central ROI drawn to 50% of height and of width of the whole right lung ROI and placed along the left lung margin and centered vertically. In general, the correlation of normalized C/P (nC/P) between the two methods was strong. However, the value of nC/P was significantly smaller for the XV method than the TT method. Regression equations for the relationship of nC/P between the two methods were, for healthy subjects, y=0.75x+0.61, R(2)=0.64 using rectangular ROIs and y=0.76x+0.45, R(2)=0.66 using isocontour ROIs; and for CF patients, y=0.94x+0.46, R(2)=0.43 and y=0.85x+0.42, R(2)=0.41, respectively. (1) A transmission scan with an isocontour outline in combination with a rectangular central region to define the lung borders may be more useful than a ventilation scan. (2) Close correlation of nC/Ps measured by transmission or gas ventilation should allow confident comparison of values determined by the two methods.

  8. 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

  9. 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

  10. Correction to BrainSCAN central axis dose calculations for 6-MV photon beams to lung with lateral electron disequilibrium

    SciTech Connect

    Geyer, Peter . E-mail: peter.geyer@mailbox.tu-dresden.de; Blank, Hilbert; Zips, Daniel; Alheit, Horst

    2006-11-15

    Purpose: To develop and evaluate a correction method for lateral electron disequilibrium and tissue inhomogeneities in lung tissues applicable to the BrainSCAN treatment planning system. Methods and Materials: Four noncoplanar 6-MV photon beams with different beam diameters were applied to the right lung of a thorax phantom. The measured/calculated dose value ratio was evaluated as a function of a parameter that describes the degree of the lateral electron disequilibrium based on the primary dose. Results: The dose ratio showed a clearcut linear dependency on the disequilibrium parameter. Applying the proposed correction method, only minor differences between the measured and calculated doses were found for lesions >1 cm. However, for lesions <1 cm surrounded by lung tissue the difference was {<=}15%. Conclusion: The data have indicated a relevant magnitude of the correction factor only for lung lesions <1 cm.

  11. Comparison of a basic lung scanning protocol against formally reported chest x‐ray in the diagnosis of pulmonary oedema

    PubMed Central

    Mitchell, Geoffrey; Thompson, Angus G; Stieler, Geoffrey

    2015-01-01

    Abstract Introduction: Brief lung scan protocols have been recommended as a useful adjunct to identify pulmonary oedema in the breathless elderly patient. Some papers quote diagnostic accuracies above that of chest x‐ray. Method: We recruited a prospective convenience sample of patients over sixty years of age reporting any breathlessness on presentation to the emergency department. Those who received both bedside lung scan and chest x‐ray later had their case notes audited by an expert cardiologist for the cause of their breathlessness at presentation. Admission diagnosis was also extracted. Results: 204 comparative data sets were collected. Compared with cardiologist chart review, delayed expert radiology report had a diagnostic accuracy of 92.2% (95%CI 87.6 to 95.1). Bedside interpretation of lung scan protocol had a diagnostic accuracy of 85.3% (95%CI 79.8 to 89.5). The difference of 6.9% between the two accuracy measures was significant (95%CI 0.69 to 13.1). Admission diagnosis accuracy, which encompasses inexpert x‐ray interpretation was 70.2%(95%CI 62.9 to 76.6), significantly less than either lung scan or expert chest x‐ray report. Conclusion: For identifying heart failure in breathless patients, urgent chest x‐ray with delayed formal report has not been shown to be redundant. Basic lung scan protocols should not yet replace chest x‐ray, but may be more reliable in the interim than inexpert clinician interpretation of chest x‐rays. PMID:28191195

  12. Distribution of perfusion.

    PubMed

    Glenny, Robb; Robertson, H Thomas

    2011-01-01

    Local driving pressures and resistances within the pulmonary vascular tree determine the distribution of perfusion in the lung. Unlike other organs, these local determinants are significantly influenced by regional hydrostatic and alveolar pressures. Those effects on blood flow distribution are further magnified by the large vertical height of the human lung and the relatively low intravascular pressures in the pulmonary circulation. While the distribution of perfusion is largely due to passive determinants such as vascular geometry and hydrostatic pressures, active mechanisms such as vasoconstriction induced by local hypoxia can also redistribute blood flow. This chapter reviews the determinants of regional lung perfusion with a focus on vascular tree geometry, vertical gradients induced by gravity, the interactions between vascular and surrounding alveolar pressures, and hypoxic pulmonary vasoconstriction. While each of these determinants of perfusion distribution can be examined in isolation, the distribution of blood flow is dynamically determined and each component interacts with the others so that a change in one region of the lung influences the distribution of blood flow in other lung regions. © 2011 American Physiological Society.

  13. Chronic hypoxia decreases arterial and venous compliance in isolated perfused rat lungs: an effect that is reversed by exogenous l-arginine

    PubMed Central

    Jin, Yi; Chen, Bernadette; Calvert, Thomas J.; Chicoine, Louis G.; Liu, Yusen

    2013-01-01

    Chronic hypoxia (CH)-induced pulmonary hypertension is characterized by vasoconstriction and vascular remodeling, leading to right ventricular dysfunction. Given the role of arterial compliance (Ca) in right ventricular work, a decrease in Ca would add to right ventricular work. Nitric oxide (NO) is a potent vasodilator made by NO synthases from l-arginine (l-Arg). However, little is known of the effect of l-Arg on vascular compliance (Cv) in the lung. We hypothesized that exposure to CH would decrease Ca and that this effect would be reversed by exogenous l-Arg. Sprague-Dawley rats were exposed to either normoxia or CH for 14 days; the lungs were then isolated and perfused. Vascular occlusions were performed and modeled using a three-compliance, two-resistor model. Pressure-flow curves were generated, and a distensible vessel model was used to estimate distensibility and a vascular resistance parameter (R0). Hypoxia resulted in the expected increase in arterial resistance (Ra) as well as a decrease in both Ca and Cv. l-Arg had little effect on Ra, Ca, or Cv in isolated lungs from normoxic animals. l-Arg decreased Ra in lungs from CH rats and redistributed compliance to approximately that found in normoxic lungs. CH increased R0, and l-Arg reversed this increase in R0. l-Arg increased exhaled NO, and inhibition of l-Arg uptake attenuated the l-Arg-induced increase in exhaled NO. These data demonstrate that the CH-induced decrease in Ca was reversed by l-Arg, suggesting that l-Arg may improve CH-induced right ventricular dysfunction. PMID:23103497

  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.

  15. Ventilation/perfusion SPECT in chronic obstructive pulmonary disease: an evaluation by reference to symptoms, spirometric lung function and emphysema, as assessed with HRCT.

    PubMed

    Jögi, Jonas; Ekberg, Marie; Jonson, Björn; Bozovic, Gracijela; Bajc, Marika

    2011-07-01

    Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation which is not fully reversible. Despite the heterogeneity of COPD, its diagnosis and staging is currently based solely on forced expiratory volume in 1 s (FEV(1)). FEV(1) does not explain the underlying pathophysiology of airflow limitation. The relationship between FEV(1), symptoms and emphysema extent is weak. Better diagnostic tools are needed to define COPD. Tomographic lung scintigraphy [ventilation/perfusion single photon emission tomography (V/P SPECT)] visualizes regional V and P. In COPD, relations between V/P SPECT, spirometry, high-resolution computed tomography (HRCT) and symptoms have been insufficiently studied. The aim of this study was to investigate how lung function imaging and obstructive disease grading undertaken using V/P SPECT correlate with symptoms, spirometric lung function and degree of emphysema assessed with HRCT in patients with COPD. Thirty patients with stable COPD were evaluated with the Medical Research Council dyspnoea questionnaire (MRC) and the clinical COPD questionnaire (CCQ). Spirometry was performed. The extent of emphysema was assessed using HRCT. V/P SPECT was used to assess V/P patterns, total reduction in lung function and degree of obstructive disease. The total reduction in lung function and degree of obstructive disease, assessed with V/P SPECT, significantly correlated with emphysema extent (r = 0.66-0.69, p < 0.0001) and spirometric lung function (r = 0.62-0.74, p < 0.0005). The correlation between emphysema extent and spirometric lung function was weaker. No correlation between MRC, CCQ and objective measurements was found. V/P SPECT is sensitive to early changes in COPD. V/P SPECT also has the possibility to identify comorbid disease. V/P SPECT findings show a significant correlation with emphysema extent and spirometric lung function. We therefore recommend that scintigraphic signs of COPD, whenever found, should be reported. V

  16. Is the predicted postoperative FEV1 estimated by planar lung perfusion scintigraphy accurate in patients undergoing pulmonary resection? Comparison of two processing methods.

    PubMed

    Caglar, Meltem; Kara, Murat; Aksoy, Tamer; Kiratli, Pinar Ozgen; Karabulut, Erdem; Dogan, Riza

    2010-07-01

    Estimation of postoperative forced expiratory volume in 1 s (FEV1) with radionuclide lung scintigraphy is frequently used to define functional operability in patients undergoing lung resection. We conducted a study to outline the reliability of planar quantitative lung perfusion scintigraphy (QLPS) with two different processing methods to estimate the postoperative lung function in patients with resectable lung disease. Forty-one patients with a mean age of 57 +/- 12 years who underwent either a pneumonectomy (n = 14) or a lobectomy (n = 27) were included in the study. QLPS with Tc-99m macroaggregated albumin was performed. Both three equal zones were generated for each lung [zone method (ZM)] and more precise regions of interest were drawn according to their anatomical shape in the anterior and posterior projections [lobe mapping method (LMM)] for each patient. The predicted postoperative (ppo) FEV1 values were compared with actual FEV1 values measured on postoperative day 1 (pod1 FEV1) and day 7 (pod 7 FEV1). The mean of preoperative FEV1 and ppoFEV1 values was 2.10 +/- 0.57 and 1.57 +/- 0.44 L, respectively. The mean of Pod1FEV1 (1.04 +/- 0.30 L) was lower than ppoFEV1 (p < 0.0001) but increased on day 7 (1.31 +/- 0.32 L) (p < 0.0001); however, it never reached the predicted values. Zone and LMMs estimated mean ppoFEV1 as 1.56 +/- 0.45 and 1.57 +/- 0.44 L, respectively. Both methods overestimated the actual value by 50% (ZM), 51% (LMM) and 19% (ZM), 20% (LMM) for pod 1 and pod 7, respectively. This overestimation was more pronounced in patients with chronic lung disease and hilar tumors. No significant differences were observed between ppoFEV1 values estimated by ZM or by LMM (p > 0.05). PpoFEV1 values predicted by both the zone and LMMs overestimated the actual measured lung volumes in patients undergoing pulmonary resection in the early postoperative period. LMM is not superior to ZM.

  17. Making sense of large data sets without annotations: analyzing age-related correlations from lung CT scans

    NASA Astrophysics Data System (ADS)

    Dicente Cid, Yashin; Mamonov, Artem; Beers, Andrew; Thomas, Armin; Kovalev, Vassili; Kalpathy-Cramer, Jayashree; Müller, Henning

    2017-03-01

    The analysis of large data sets can help to gain knowledge about specific organs or on specific diseases, just as big data analysis does in many non-medical areas. This article aims to gain information from 3D volumes, so the visual content of lung CT scans of a large number of patients. In the case of the described data set, only little annotation is available on the patients that were all part of an ongoing screening program and besides age and gender no information on the patient and the findings was available for this work. This is a scenario that can happen regularly as image data sets are produced and become available in increasingly large quantities but manual annotations are often not available and also clinical data such as text reports are often harder to share. We extracted a set of visual features from 12,414 CT scans of 9,348 patients that had CT scans of the lung taken in the context of a national lung screening program in Belarus. Lung fields were segmented by two segmentation algorithms and only cases where both algorithms were able to find left and right lung and had a Dice coefficient above 0.95 were analyzed. This assures that only segmentations of good quality were used to extract features of the lung. Patients ranged in age from 0 to 106 years. Data analysis shows that age can be predicted with a fairly high accuracy for persons under 15 years. Relatively good results were also obtained between 30 and 65 years where a steady trend is seen. For young adults and older people the results are not as good as variability is very high in these groups. Several visualizations of the data show the evolution patters of the lung texture, size and density with age. The experiments allow learning the evolution of the lung and the gained results show that even with limited metadata we can extract interesting information from large-scale visual data. These age-related changes (for example of the lung volume, the density histogram of the tissue) can also be

  18. Ventilation-perfusion scintigraphy in the PIOPED study. Part I. Data collection and tabulation.

    PubMed

    Gottschalk, A; Juni, J E; Sostman, H D; Coleman, R E; Thrall, J; McKusick, K A; Froelich, J W; Alavi, A

    1993-07-01

    The Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study of more than 700 patients is the largest existing study of the accuracy of lung scintigraphy in the diagnosis of acute pulmonary embolism. Perfusion scans were obtained in all patients and ventilation scans in almost all, using standardized techniques. Chest radiographs were obtained in all patients within 12 hr of the lung scan. Most patients underwent pulmonary arteriography. The images were interpreted according to a set of interpretive criteria which remained constant throughout the trial. A standardized, detailed description of each image set was derived by consensus of teams of two readers blinded to clinical and arteriographic findings. This communication reports the methods used to describe and categorize the ventilation-perfusion scintigrams obtained in patients who were enrolled in the PIOPED study. Scintigraphic technique is reviewed briefly, probability assessment is described and the scan description is reviewed in detail. The form used to describe the findings on ventilation-perfusion scans is reproduced. Use of this standardized description permits retrospective evaluation of the PIOPED interpretive criteria. In addition, it represents a rigorous approach to scan analysis which could facilitate application of formal interpretive schemes and enhance the reproducibility of lung scan interpretations in the clinical setting.

  19. Tomographic ventilation/perfusion lung scintigraphy in the monitoring of the effect of treatment in pulmonary embolism: serial follow-up over a 6-month period.

    PubMed

    Begic, Amela; Jögi, Jonas; Hadziredzepovic, Amra; Kucukalic-Selimović, Elma; Begovic-Hadzimuratovic, Sadzida; Bajc, Marika

    2011-06-01

    Pulmonary embolism (PE) is a severe condition with nonspecific symptoms. Diagnosis relies on medical imaging but follow-up is currently based on clinical symptoms and general risk factors. The duration of anticoagulant treatment after an acute episode of PE is still subject to debate and the best method of identifying the risk of recurrence in individual patients is undefined. Tomographic lung scintigraphy [ventilation/perfusion single photon emission computed tomography (V/P SPECT)] has improved the diagnostic accuracy with regard to PE but has not been evaluated for PE follow-up. The aim of this prospective study was to quantitatively follow the natural history of treated PE using V/P SPECT, which could prove helpful in defining an anticoagulant treatment regime for individual patients. Of 83 consecutive patients with clinically suspected PE examined with V/P SPECT, 23 patients with confirmed PE were followed by serial V/P SPECT examinations over a 6-month period. All patients were also followed clinically. The mean relative decrease in PE extent compared with the time of diagnosis was 54±26% at 2 weeks, 79±30% at 3 months, and 82±30% at 6 months. Significant resolution of mismatched perfusion defects occurred between V/P SPECT controls within the first 3 months of anticoagulation (P<0.001) but not thereafter. V/P SPECT identified four patients with chronic PE, even though all patients were free from symptoms at 3-month follow-up. Follow-up of PE with V/P SPECT is feasible to evaluate treatment effectiveness in individual patients and to identify patients that develop chronic PE. This study also confirms that resolution of perfusion defects after PE occurs within the first 3 months of treatment. It is therefore recommended that V/P SPECT follow-up should be considered at 3 months after diagnosis.

  20. Correlation between plasma brain natriuretic peptide concentration and lung thallium-201 uptake on exercise thallium perfusion images.

    PubMed

    Inoue, Noriko; Takahashi, Nobukazu; Kimura, Kazuo; Ishikawa, Toshiyuki; Toyama, Shinichi; Yoshii, Yuzuru; Uchino, Kazuaki; Yamakawa, Yohei; Matsumoto, Katsumi; Inoue, Tomio; Umemura, Satoshi

    2006-03-01

    The plasma brain natriuretic peptide (BNP) concentration at rest correlates with left ventricular end-diastolic pressure (LVEDP), left ventricular ejection fraction (LVEF), and pulmonary capillary wedge pressure (PCWP). High lung thallium-201 uptake has been reported to be associated with hemodynamic variables such as LVEDP, LVEF, and PCWP. However, there is no study that has investigated the correlation of plasma BNP concentration with lung thallium-201 uptake. We examined whether the plasma BNP concentration was related to lung thallium-201 uptake. Before exercise, venous blood samples were obtained from 39 patients with old myocardial infarction. We investigated the correlations between plasma BNP concentration and lung thallium-201 uptake, and whether they were related to LVEF, extent of nonviable myocardium, and ischemic myocardium, respectively, with thallium-201 exercise stress testing. The plasma BNP concentration significantly correlated with lung thallium-201 uptake (P < 0.05), nonviable segments (P < 0.01), and LVEF (P < 0.01). Lung thallium-201 uptake correlated with nonviable segments (P < 0.01). Our results suggest that increased secretion of BNP is related to increased lung thallium-201 uptake, and they are related to the extent of nonviable myocardium and decreased left ventricular function. Plasma BNP concentration and lung thalium-201 uptake may reflect the extent of myocardial fibrosis causing myocyte stretch.

  1. Modeling the bifurcating flow in a CT-scanned human lung airway.

    PubMed

    Luo, H Y; Liu, Y

    2008-08-28

    The inspiratory flow characteristics in a CT-scanned human lung model were numerically investigated using low Reynolds number (LRN) kappa-omega turbulent model. The five-generation airway is extracted from the trachea to segmental bronchi of a 60-year-old Chinese male patient. Computations were carried out in the Reynolds number range of 900-2100, corresponding to mouth-air breathing rates of 190-440 ml/s. Flow patterns on the Re=2100 and flow rate distribution were presented. In this model, the flow pattern is very complex. To count the effect of laryngeal jet on trachea inlet, the trachea was extended and modified to simulate the larynx, consequently the inlet velocity profile is biased towards the rear wall. In the inferior lobar bronchi, there are two stems in which the axial velocity is stronger but secondary velocity is weaker. Secondary flow in the lateral bronchi is stronger than the medial ones. With increasing Re, the air flow increases in the middle, inferior lobes and left main bronchus, i.e., flow biases to left and downward.

  2. Optimal scan parameters for CT fluoroscopy in lung interventional radiologic procedures: relationship between radiation dose and image quality.

    PubMed

    Yamao, Yoshikazu; Yamakado, Koichiro; Takaki, Haruyuki; Yamada, Tomomi; Murashima, Shuichi; Uraki, Junji; Kodama, Hiroshi; Nagasawa, Naoki; Takeda, Kan

    2010-04-01

    To evaluate the relationship between radiation doses and lung computed tomographic (CT) fluoroscopic scan parameters and to determine optimal scan parameters for performance of lung interventional radiologic (IR) procedures. The institutional review board approved this prospective study, which included 32 patients with a single lung tumor; written informed consent was obtained. CT fluoroscopic images were obtained with three tube voltages (80,120,135 kV) and three tube currents (10, 20, 30 mA) in each patient. The signal-to-noise ratios (SNRs) and the contrast-to-noise ratios (CNRs) were measured quantitatively. To evaluate the feasibility of performing lung IR procedures, four readers visually scored the image quality. Acceptable CT fluoroscopic images were determined by using agreement of at least three of the four readers. The weighted CT dose index for each CT scan parameter was measured. A piecewise linear regression equation was obtained from the relationship between radiation doses and visual image scores. Both the SNR and the CNR improved as the radiation dose increased, leading to improvement in the image quality. Acceptable image quality was achieved in 94% (30 of 32) of patients when the radiation dose was 1.18 mGy/sec (120 kV, 10 mA) and in all patients when it was greater than 1.48 mGy/sec (135 kV, 10 mA). The piecewise linear curve showed rapid improvement in image quality until the radiation dose increased to 1.48 mGy/sec (135 kV, 10 mA). When the radiation dose was increased greater than 1.48 mGy/sec, improvement in the image quality became more gradual. Results of this study can be used to guide the determination of optimal scan parameters in lung CT fluoroscopy. RSNA, 2010

  3. Dynamic contrast-enhanced perfusion area detector CT for non-small cell lung cancer patients: Influence of mathematical models on early prediction capabilities for treatment response and recurrence after chemoradiotherapy.

    PubMed

    Ohno, Yoshiharu; Koyama, Hisanobu; Fujisawa, Yasuko; Yoshikawa, Takeshi; Seki, Shinichiro; Sugihara, Naoki; Sugimura, Kazuro

    2016-01-01

    To determine the capability and influence of the mathematical method on dynamic contrast-enhanced (CE-) perfusion area detector CT (ADCT) for early prediction of treatment response as well as progression free and overall survival (PFS and OS) of non-small cell lung cancer (NSCLC) patients treated with chemoradiotherapy. Sixty-six consecutive stage III NSCLC patients underwent dynamic CE-perfusion ADCT examinations, chemoradiotherapy and follow-up examinations. Response Evaluation Criteria in Solid Tumors (RECIST) criteria were used to divide all patients into responders and non-responders. Differences in each of the indices for all targeted lesions between measurements obtained 2 weeks prior to the first and the third course of chemotherapy were determined for all patients. ROC analyses were employed to determine the capability of perfusion indices as markers for distinguishing RECIST responders from non-responders. To evaluate their capability for early prediction of therapeutic effect, OS of perfusion index-based responders and non-responders were compared by using the Kaplan-Meier method followed by log-rank test. Area under the curve (Az) for total perfusion by means of the dual-input maximum slope method was significantly larger than that of pulmonary arterial perfusion using the same method (p=0.007) and of perfusion with the single-input maximum slope method (p=0.007). Mean OS demonstrated significantly difference between responder- and non-responder groups for total perfusion (p=0.02). Mathematical models have significant influence on assessment for early prediction of treatment response, disease progression and overall survival using dynamic CE-perfusion ADCT for NSCLC patients treated with chemoradiotherapy. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. Ventilation/perfusion lung scintigraphy: what is still needed? A review considering technetium-99m-labeled macro-aggregates of albumin.

    PubMed

    Zöphel, Klaus; Bacher-Stier, Claudia; Pinkert, Jörg; Kropp, Joachim

    2009-01-01

    Lung perfusion scintigraphy (LPS) with technetium-99m-labeled macro-aggregates of albumin (Tc-99m-MAA) is well established in the diagnostic of pulmonary embolism (PE). In the last decade, it was shown that single-photon emission computer tomography (SPECT) acquisition of LPS overcame static scintigraphy. Furthermore, there are rare indications for LPS, such as preoperative quantification of regional lung function prior to lung resection or transplantation, optimization of lung cancer radiation therapy, quantification of right-left shunt, planning of intra-arterial chemotherapy, and several rare indications in pediatrics. Moreover, LPS with Tc-99m-MAA is a safe method with low radiation exposure. PE can also be diagnosed by spiral computer tomography (CT), ultrasound, magnetic resonance angiography, or pulmonary angiography (PA, former gold standard). The present review considers all these methods, especially spiral CT, and compares them with LPS with respect to sensitivity and specificity and gives an overview of established and newer publications. It shows that LPS with Tc-99m-MAA represents a diagnostic method of continuing value for PE. In comparison with spiral CT and/or PA, LPS is not to be defeated as mentioned also by the most actual Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) II reports. This applies in particular to chronic or recurring embolisms, whereas currently spiral CT may be of greater value for major or life-threatening embolisms. At present, LPS cannot be replaced by other methods in some applications, such as pediatrics or in the quantification of regional pulmonary function in a preoperative context or prior to radiation therapy. LPS still has a place in the diagnostics of PE and is irreplaceable in several rare indications as described earlier.

  5. Development of pulmonary blood flow evaluation method with a dynamic flat-panel detector: quantitative correlation analysis with findings on perfusion scan.

    PubMed

    Tanaka, Rie; Sanada, Shigeru; Fujimura, Masaki; Yasui, Masahide; Hayashi, Norio; Tsuji, Shiro; Okamoto, Hiroyuki; Nanbu, Yuko; Matsui, Osamu

    2010-01-01

    Pulmonary blood flow is reflected in dynamic chest radiographs as changes in X-ray translucency, i.e., pixel values. Thus, decreased blood flow should be observed as a reduction of the variation of X-ray translucency. We performed the present study to investigate the feasibility of pulmonary blood flow evaluation with a dynamic flat-panel detector (FPD). Sequential chest radiographs of 14 subjects were obtained with a dynamic FPD system. The changes in pixel value in each local area were measured and mapped on the original image by use of a gray scale in which small and large changes were shown in white and black, respectively. The resulting images were compared to the findings in perfusion scans. The cross-correlation coefficients of the changes in pixel value and radioactivity counts in each local area were also computed. In all patients, pulmonary blood flow disorder was indicated as a reduction of changes in pixel values on the mapping image, and a correlation was observed between the distribution of changes in pixel value and those in radioactivity counts (0.7

  6. Rheumatoid arthritis-associated interstitial lung disease: lung inflammation evaluated with high resolution computed tomography scan is correlated to rheumatoid arthritis disease activity.

    PubMed

    Pérez-Dórame, Renzo; Mejía, Mayra; Mateos-Toledo, Heidegger; Rojas-Serrano, Jorge

    2015-01-01

    To describe the association between rheumatoid arthritis disease activity (RA) and interstitial lung damage (inflammation and fibrosis), in a group of patients with rheumatoid arthritis-associated interstitial lung disease (RA-ILD). A retrospective study of RA patients with interstitial lung disease (restrictive pattern in lung function tests and evidence of interstitial lung disease in high resolution computed tomography (HRCT)). Patients were evaluated to exclude other causes of pulmonary disease. RA disease activity was measured with the CDAI index. Interstitial lung inflammation and fibrosis were determined by Kazerooni scale. We compared Kazerooni ground-glass score with the nearest CDAI score to HRCT date scan of the first medical evaluation at our institution. In nine patients, we compared the first ground-glass score with a second one after treatment with DMARDs and corticosteroids. Spearman's rank correlation coefficient was used to evaluate association between RA disease activity and the Kazerooni ground-glass and fibrosis scores. Thirty-four patients were included. A positive correlation between CDAI and ground-glass scores was found (rs=0.3767, P<0.028). Fibrosis and CDAI scores were not associated (rs=-0.0747, P<0.6745). After treatment, a downward tendency in the ground-glass score was observed (median [IQR]): (2.33 [2,3] vs. 2 [1.33-2.16]), P<0.056, along with a lesser CDAI score (27 [8-43] vs. 9 [5-12]), P<0.063. There is a correlation between RA disease activity and ground-glass appearance in the HRCT of RA-ILD patients. These results suggest a positive association between RA disease activity and lung inflammation in RA-ILD. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.

  7. Deformable lung registration between exhale and inhale CT scans using active cells in a combined gradient force approach.

    PubMed

    Yim, Yeny; Hong, Helen; Shin, Yeong Gil

    2010-08-01

    This article proposes an accurate and fast deformable registration method between end-exhale and end-inhale CT scans that can handle large lung deformations and accelerate the registration process. The density correction method is applied to reduce the density difference between two CT scans due to respiration and gravity. The lungs are globally aligned by affine registration and nonlinearly deformed by a demons algorithm using a combined gradient force and active cells. The use of combined gradient force allows a fast convergence in the lung regions with a weak gradient of the target image by taking into account the gradient of the source image. The use of active cells helps to accelerate the registration process and reduce the degree of deformation folding because it avoids unnecessary computation of the displacement for well-matched lung regions. The proposed method was tested with end-exhale and end-inhale CT scans acquired from eight normal subjects. The performance of the proposed method was evaluated through comparisons of methods that use a target gradient force or a combined gradient force, as well as methods with and without active cells. The proposed method with combined gradient force led to significantly higher accuracy compared to the method with target gradient force. For the entire lung, the proposed method provided a mean landmark error of 2.8 +/- 1.5 mm. For the lower 30% part of the lungs, the Dice similarity coefficient and normalized cross correlation of the proposed method were higher than the original demon algorithm by 2.3% (p=0.0172) and 2.2% (p=0.0028), respectively. The proposed method with an active cell led to fewer voxels with negative Jacobian values and a 55% decrease of processing time compared to the method without an active cell. The results show that the proposed method can accurately register lungs with large deformations and can considerably reduce the processing time. The proposed deformable registration technique can be used

  8. Reversible bronchial dilatation in children: comparison of serial high-resolution computer tomography scans of the lungs.

    PubMed

    Gaillard, E A; Carty, H; Heaf, D; Smyth, R L

    2003-09-01

    Bronchiectasis is generally considered irreversible in the adult population, largely based on studies employing bronchography in cases with a significant clinical history. It is assumed, that the same is true for children. Few studies have examined the natural history of bronchiectasis in children and diagnostic criteria on high-resolution computer tomography of the lungs are derived from studies on adults. Frequently, bronchiectasis is reported in children in cases where localised bronchial dilatation is present, incorrectly labelling these children with an irreversible life-long condition. to evaluate changes in appearance of bronchial dilatation, unrelated to cystic fibrosis in children, as assessed by sequential high-resolution computer tomography (HRCT) of the lungs. The scans of 22 children with a radiological diagnosis of bronchiectasis, seen at Alder Hey Children's Hospital between 1994 and 2000, who had at least two CT scans of the lungs were reviewed by a single radiologist, who was blinded to the original report. Following a median scan interval of 21 months (range 2-43), bronchial dilatation resolved completely in six children and there was improvement in appearances in a further eight, with medical treatment alone. A radiological diagnosis of bronchiectasis should be considered with caution in children as diagnostic criteria derived from studies in adults have not been validated in children and the condition is generally considered irreversible.

  9. Automated segmentation refinement of small lung nodules in CT scans by local shape analysis.

    PubMed

    Diciotti, Stefano; Lombardo, Simone; Falchini, Massimo; Picozzi, Giulia; Mascalchi, Mario

    2011-12-01

    One of the most important problems in the segmentation of lung nodules in CT imaging arises from possible attachments occurring between nodules and other lung structures, such as vessels or pleura. In this report, we address the problem of vessels attachments by proposing an automated correction method applied to an initial rough segmentation of the lung nodule. The method is based on a local shape analysis of the initial segmentation making use of 3-D geodesic distance map representations. The correction method has the advantage that it locally refines the nodule segmentation along recognized vessel attachments only, without modifying the nodule boundary elsewhere. The method was tested using a simple initial rough segmentation, obtained by a fixed image thresholding. The validation of the complete segmentation algorithm was carried out on small lung nodules, identified in the ITALUNG screening trial and on small nodules of the lung image database consortium (LIDC) dataset. In fully automated mode, 217/256 (84.8%) lung nodules of ITALUNG and 139/157 (88.5%) individual marks of lung nodules of LIDC were correctly outlined and an excellent reproducibility was also observed. By using an additional interactive mode, based on a controlled manual interaction, 233/256 (91.0%) lung nodules of ITALUNG and 144/157 (91.7%) individual marks of lung nodules of LIDC were overall correctly segmented. The proposed correction method could also be usefully applied to any existent nodule segmentation algorithm for improving the segmentation quality of juxta-vascular nodules.

  10. Are minimized perfusion circuits the better heart lung machines? Final results of a prospective randomized multicentre study.

    PubMed

    El-Essawi, A; Hajek, T; Skorpil, J; Böning, A; Sabol, F; Ostrovsky, Y; Hausmann, H; Harringer, W

    2011-11-01

    Minimized perfusion circuits (MPCs), although aiming at minimizing the adverse effects of cardiopulmonary bypass, have not yet gained popularity. This can be attributed to concerns regarding their safety, as well as lack of sufficient evidence of their benefit. Described is a randomized, multicentre study comparing the MPC - ROCsafeRX to standard cardiopulmonary bypass in patients undergoing elective coronary artery bypass grafting and/ or aortic valve replacement. Five hundred patients were included in the study (252 randomized to the ROCsafeRX group and 248 to standard cardiopulmonary bypass). Both groups were well matched for demographic characteristics and type of surgery. No operative mortality and no device-related complications were encountered. Transfusion requirement (333 ± 603 vs. 587 ± 1010 ml; p=0.001), incidence of atrial fibrillation (16.3% vs. 24.2%; p=0.03) and the incidence of major adverse events (9.1% vs. 16.5%; p=0.02) were all in favour of the MPC group. These results confirm both the safety and efficacy of the ROCsafeRX MPC for a large variety of cardiac patients. Minimized perfusion circuits should, therefore, play a greater role in daily practice so that as many patients as possible can benefit from their advantages.

  11. Robust Initialization of Active Shape Models for Lung Segmentation in CT Scans: A Feature-Based Atlas Approach

    PubMed Central

    Beichel, Reinhard R.

    2014-01-01

    Model-based segmentation methods have the advantage of incorporating a priori shape information into the segmentation process but suffer from the drawback that the model must be initialized sufficiently close to the target. We propose a novel approach for initializing an active shape model (ASM) and apply it to 3D lung segmentation in CT scans. Our method constructs an atlas consisting of a set of representative lung features and an average lung shape. The ASM pose parameters are found by transforming the average lung shape based on an affine transform computed from matching features between the new image and representative lung features. Our evaluation on a diverse set of 190 images showed an average dice coefficient of 0.746 ± 0.068 for initialization and 0.974 ± 0.017 for subsequent segmentation, based on an independent reference standard. The mean absolute surface distance error was 0.948 ± 1.537 mm. The initialization as well as segmentation results showed a statistically significant improvement compared to four other approaches. The proposed initialization method can be generalized to other applications employing ASM-based segmentation. PMID:25400660

  12. Correlation between lung scintigraphy and long-term outcome in survivors of congenital diaphragmatic hernia.

    PubMed

    Okuyama, Hiroomi; Kubota, Akio; Kawahara, Hisayoshi; Oue, Takaharu; Kitayama, Yasuhiro; Yagi, Makoto

    2006-09-01

    Lung scintigraphy has been used to evaluate the degree of pulmonary hypoplasia in infants with congenital diaphragmatic hernia (CDH). However, the relationship between lung scintigraphy and long-term outcome of CDH remains unclear. The aim of this study is to determine whether lung scintigraphy correlates with long-term pulmonary morbidity and nutritional status in survivors of CDH. Consecutive 31 survivors of CDH were enrolled in this study. The initial scan was per