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Biomedical subjects

David M Hansell

Publications and source records attributed to David M Hansell.

At least 37 records · Page 2Linked to original sources
PubMed2003

Drug-induced pneumonitis and heart failure simultaneously associated with venlafaxine.

Two cases of interstitial pneumonia with cardiac failure developing in patients treated with the new antidepressant venlafaxine are presented. A strong relationship between the development of the patients' illness and the initiation of venlafaxine treatment was identified. The cytochrome P (CYP) 450 system is involved in the metabolism of venlafaxine, suggesting that alterations in the drug metabolic clearance might be, at least in part, responsible for the development of drug-induced damage in these cases. This might occur either as a consequence of a genetic factor or concomitant drug therapy with an inhibitor of the related CYP system. After identifying the causative agent in the first case, withdrawal of the antidepressant together with corticosteroid treatment led to a favorable outcome. In the other case, the multiorgan failure became fatal. These cases highlight a hitherto undescribed association of an adverse lung reaction and heart failure due to venlafaxine.

Adult↗
PubMed2003

Idiopathic pulmonary fibrosis: a composite physiologic index derived from disease extent observed by computed tomography.

In idiopathic pulmonary fibrosis, the quantitation of disease severity using pulmonary function tests is often confounded by emphysema. We have identified the composite physiologic index (CPI) most closely reflecting the morphologic extent of pulmonary fibrosis. Consecutive patients with a clinical/computed tomography (CT) diagnosis of idiopathic pulmonary fibrosis (n = 212) were divided into group I (n = 106) and group II (n = 106). The CPI was derived in group I (by fitting pulmonary function tests against disease extent on CT) and was tested in Group II. The formula for the CPI was as follows: extent of disease on CT = 91.0 - (0.65 x percent predicted diffusing capacity for carbon monoxide [DLCO]) - (0.53 x percent predicted FVC) + (0.34 x percent predicted FEV1). In group II, the CPI correlated more strongly with disease extent on CT (r2 = 0.51) than the individual pulmonary function test (DLCO the highest value, r2 = 0.38). A subanalysis demonstrated that the better fit of the CPI was ascribable to a correction of the confounding effects of emphysema. Mortality was predicted more accurately by the CPI than by a pulmonary function test in all clinical subgroups, including a separate cohort of 36 patients with histologically proven usual interstitial pneumonia (CPI, p < 0.0005; FVC, p = 0.002; PO2, p = 0.002). In conclusion, a new CPI, derived against CT and validated using split sample testing, is a more accurate prognostic determinant in usual interstitial pneumonia than an individual pulmonary function test.

Aged↗
PubMed2003

Bronchoscopic volume reduction with valve implants in patients with severe emphysema.

Eight patients with severe emphysema entered a pilot study of unilateral volume reduction by endobronchial valve insertion. Five patients had emphysema judged too severe for volume reduction surgery and three refused the operation. After valve insertions, the median forced expiratory volume in 1 s (FEV1) increased from 0.79 L (range 0.61-1.07) to 1.06 L (0.75-1.22) (difference 34%, p=0.028) and the median diffusing capacity (TL(CO)) increased from 3.05 mL/min/mm Hg (2.35-4.71) to 3.92 mL/min/mm Hg (2.89-5.40) (difference 29%, p=0.017). CT scans showed a substantial reduction in regional volume in four of the eight patients. Two patients developed a transient pneumothorax (one requiring drainage) but we recorded no other important adverse effects during follow-up. Lung-volume reduction can be achieved with unilateral bronchoscopically placed valve implants in patients with severe emphysema with acceptable short-term safety and worthwhile functional benefits.

Adult↗
PubMed2003

Extra-thoracic staging of lung cancer.

This article reviews the staging of extra-thoracic metastatic lung cancer. The imaging strategy, including when to screen as well as the different modalities available for different sites of spread of disease are discussed. The emerging role of whole body positron emission tomography in screening for metastases is also explored.

Adrenal Gland Neoplasms↗
PubMed2003

Staging of non-small cell lung cancer: imaging of intrathoracic disease.

This article reviews the contribution of diagnostic imaging to the intrathoracic staging of non-small cell lung cancer. The principle features of the current staging system are discussed along with the relative roles of the various imaging modalities in the evaluation of the primary tumour and metastatic disease. The emerging role of positron emission tomography with fluorodeoxyglucose (FDG-PET) as a clinically useful, potentially cost effective, complementary imaging technique is also reviewed.

Carcinoma, Non-Small-Cell Lung↗
PubMed2003

Smoking-related diffuse parenchymal lung disease: HRCT-pathologic correlation.

Response by the lung to inhaled cigarette smoke varies widely between individuals and ranges from subclinical respiratory bronchiolitis to end-stage Langerhans' cell histiocytosis. The variety of interstitial lung diseases associated with cigarette smoking is wider than generally appreciated, and these often coexist. An understanding of the pathological basis of smoking-related lung disease helps to explain the sometimes complex patterns encountered on high-resolution computed tomography (HRCT). The recent refinement of the classification of the idiopathic interstitial pneumonias and the longitudinal study of cigarette smokers with HRCT has furthered understanding of what should be regarded as an overlapping group of entities. In this article the individual interstitial diseases ascribable to cigarette smoking are discussed in terms of their pathology and corresponding HRCT signs. Emphasis is placed on the frequent coexistence of various forms of smoking-related interstitial lung disease.

Journal Article↗
PubMed2003

Respiratory bronchiolitis-associated interstitial lung disease.

Respiratory bronchiolitis-associated interstitial lung disease (RBILD) can be viewed as an exaggerated respiratory bronchiolitic response to cigarette smoke. The histologic, high-resolution computed tomographic (HRCT) and bronchoalveolar lavage (BAL) features of RBILD overlap substantially with those of respiratory bronchiolitis, with the diagnosis of RBILD being based upon the severity of disease, as judged by symptoms, clinical signs, the severity of lung function impairment, and the extent of abnormalities on HRCT. Typical histologic appearances consist of an accumulation of pigmented macrophages within respiratory bronchioles, associated with peribronchial chronic inflammatory cell infiltration and, variably, peribronchial fibrotic alveolar septal thickening. Characteristic HRCT findings include poorly defined centrilobular micronodules, patchy limited ground-glass attenuation, bronchial wall thickening, and areas of regional hypoattenuation. The ventilatory defect is often mixed but is usually predominantly restrictive. The diagnosis of RBILD is often made on clinical and HRCT criteria, with BAL findings providing useful diagnostic support, but a thoracoscopic biopsy continues to be required when other features are atypical. RBILD may regress with discontinuation of smoking but often persists with no functional improvement despite smoking cessation and treatment. Nonetheless, the course tends to be benign, without inexorable deterioration. This article outlines the rationale for viewing RBILD and desquamative interstitial pneumonia as separate entities, rather than two ends of the same disease spectrum (based upon overlapping histologic and HRCT features).

Journal Article↗
PubMed2003

Terminal diffuse alveolar damage in relation to interstitial pneumonias. An autopsy study.

Acute exacerbations of idiopathic pulmonary fibrosis/cryptogenic fibrosing alveolitis (IPF/CFA) are rare and typically terminal events, but their relationship to underlying patterns of idiopathic interstitial pneumonias is unknown. We reviewed autopsy material from patients who died of diffuse alveolar damage in the clinical setting of pulmonary fibrosis, both idiopathic and with background fibrosing alveolitis with connective tissue disorders (FA-CTDs), and compared them with cases of acute interstitial pneumonia. Of 15 patients with acute exacerbations of IPF/CFA (n = 12) or FA-CTD (n = 3), 12 had a background pattern of usual interstitial pneumonia and 3 had fibrotic nonspecific interstitial pneumonia. All cases of fibrotic nonspecific interstitial pneumonia were seen in association with FA-CTD. The cause of acute exacerbations is unknown, but our data suggest that toxic effects of oxygen and triggering infection are unlikely causes. In patients with CTDs, it remains uncertain whether the acute exacerbation is related to the fibrosis, the associated CTD, or a combination of these factors. Acute exacerbations of IPF/CFA may be a more common terminal event than previously thought.

Aged↗
PubMed2002

Traction bronchiectasis in cryptogenic fibrosing alveolitis: associated computed tomographic features and physiological significance.

Our objective was to evaluate the associated CT features and physiological consequences of traction bronchiectasis in patients with cryptogenic fibrosing alveolitis (CFA). The CT scans of 212 patients with CFA (158 men, 54 women; mean age 62.2+/-10.6 years) were evaluated independently by two observers. The extent of fibrosis, the proportions of a reticular pattern and ground-glass opacification and the extent of emphysema were scored at five levels. The predominant CT pattern, coarseness of a reticular pattern and severity of traction bronchiectasis were graded semiquantitatively. Physiological indices were correlated with CT features. There was traction bronchiectasis on CT in 202 of 212 (95%) patients. Increasingly severe traction bronchiectasis was independently associated with increasingly extensive CFA ( p<0.0005), a coarser reticular pattern ( p<0.001), a lower proportion of ground-glass opacification ( p<0.005) and less extensive emphysema ( p<0.0005). Increasingly severe traction bronchiectasis was independently related to depression of DL(CO) ( p<0.005), FVC ( p=0.02) and pO(2) ( p<0.0005), but not indices of air-flow obstruction. In CFA, traction bronchiectasis increases with more extensive disease, a lower proportion of ground-glass opacification and a coarser reticular pattern, but it decreases with concurrent emphysema. Increasingly severe traction bronchiectasis is associated with additional physiological impairment for a given extent of pulmonary fibrosis and emphysema.

Bronchiectasis↗
PubMed2002

The relationship between individual histologic features and disease progression in idiopathic pulmonary fibrosis.

We have retrospectively studied 53 patients with idiopathic pulmonary fibrosis and a histologic diagnosis of usual interstitial pneumonia and evaluated the prognostic significance of four individual histologic features (fibroblastic foci [FF], interstitial mononuclear cell infiltrate, established fibrosis, and intra-alveolar macrophages) using a semiquantitative scale of 0-6. An objective count of FF was also undertaken. Using weighted kappa coefficients, interobserver agreement between pathologists was moderate to good (0.56-0.76). Subjective and objective FF scores were strongly associated (R(S) = 0.88, < 0.00005). Mortality was independently linked to a high FF score, p = 0.006, and a low percent predicted carbon monoxide diffusing capacity (DL(CO)), p = 0.01. For pulmonary function, on univariate analysis, the strongest correlations were observed between increasing interstitial mononuclear cell infiltrate or FF scores and greater declines in forced vital capacity (FVC) or DL(CO) at 6 months. Multivariate models revealed that increasing FF scores were independently associated with greater declines in FVC and DL(CO) at both 6 and 12 months. Increasing interstitial mononuclear cell infiltrate scores were also independently linked to functional decline, but only at 6 months. These data suggest a reproducible method on biopsy for predicting rate of disease progression in patients with idiopathic pulmonary fibrosis.

Biopsy↗
PubMed2002

Loss of FEV1 in cystic fibrosis: correlation with HRCT features.

The purpose of this study was to determine which high-resolution computed tomography (HRCT) features in patients with cystic fibrosis are most strongly associated with functional impairment as expressed by forced expiratory volume in one second (FEV1). Forty-seven patients with cystic fibrosis underwent chest HRCT and had pulmonary function tests. The HRCT examinations were evaluated for 11 features scored using a modification of Bhalla system and FEV1 was recorded as percentage of the predicted value. Univariate and multivariate correlations between HRCT scores and FEV1 were performed. The most common HRCT feature was bronchiectasis (98%) followed by atelectasis-consolidation (81%), bronchial wall thickening (77%), tree-in-bud sign (74%), mucous plugging (72%) and mosaic perfusion pattern (47%). On univariate analysis the following features correlated strongly with FEV1: bronchial wall thickening ( p<0.0000001), tree-in-bud sign ( p<0.0000001), mucous plugging ( p<0.0000001), atelectasis-consolidation (p<0.0000001), thickening of interlobular septa ( p<0.0002), severity ( p<0.0002) and extent of bronchiectasis ( p<0.0002). On multivariate analysis bronchial wall thickening and atelectasis-consolidation were the strongest independent determinants of the FEV1. We found a regression equation between FEV1 and the two HRCT features: FEV1=constant variable+a multiplied by bronchial wall thickening+b multiplied by atelectasis-consolidation (a and b=regression coefficients, R(2)=0.48). The major morphological determinants of functional abnormality in cystic fibrosis, as expressed by the loss of FEV1, are bronchial wall thickening and atelectasis-consolidation.

Adolescent↗
PubMed2002

Successful treatment of endogenous lipoid pneumonia due to Niemann-Pick Type B disease with whole-lung lavage.

In Type B Niemann-Pick disease, progressive pulmonary infiltration is a major cause of morbidity and mortality, although the disease is usually diagnosed before adulthood in other organ systems. To date, no successful treatment of pulmonary involvement by Niemann-Pick disease has been documented. We describe the case of a patient with Niemann-Pick Type B disease who presented with extensive endogenous lipoid pneumonia and life-threatening hypoxia following bypass grafting for severe coronary artery disease. A surgical lung biopsy at the time of grafting revealed characteristic histology and ultrastructural features of Niemann-Pick disease, with confirmatory findings in biochemical studies. Because of the severity of the patient's symptoms, bilateral whole-lung lavage was undertaken, leading to symptomatic improvement, lessening of parenchymal opacification on high-resolution computed tomographic scanning, and a marked improvement in resting arterial oxygen tension while breathing air to 10.3 kPa from 8.4 kPa. Whole-lung lavage may be a potentially useful modality of treatment for patients with pulmonary involvement by Niemann-Pick Type B disease.

Anti-Inflammatory Agents↗
PubMed2002

The use of visual search for knowledge gathering in image decision support.

This paper presents a new method of knowledge gathering for decision support in image understanding based on information extracted from the dynamics of saccadic eye movements. The framework involves the construction of a generic image feature extraction library, from which the feature extractors that are most relevant to the visual assessment by domain experts are determined automatically through factor analysis. The dynamics of the visual search are analyzed by using the Markov model for providing training information to novices on how and where to look for image features. The validity of the framework has been evaluated in a clinical scenario whereby the pulmonary vascular distribution on Computed Tomography images was assessed by experienced radiologists as a potential indicator of heart failure. The performance of the system has been demonstrated by training four novices to follow the visual assessment behavior of two experienced observers. In all cases, the accuracy of the students improved from near random decision making (33%) to accuracies ranging from 50% to 68%.

Algorithms↗
PubMed2002

Asymmetric ARDS following pulmonary resection: CT findings initial observations.

PURPOSE: To investigate whether asymmetric distribution of acute respiratory distress syndrome (ARDS) following lobectomy is due to compensatory hyperexpansion of the residual lung within the hemithorax operated on and to discern if this distribution reflects true asymmetry of the disease process. MATERIALS AND METHODS: Retrospective review of the intensive care unit database was performed over a period of 6 years to identify all cases of lung injury following lung surgery that satisfied the American-European consensus criteria for ARDS. Time to onset following surgery, time of subsequent computed tomographic (CT) examination, patient age and sex, and nature of surgery were recorded, as well as eventual patient status (ie, death or discharge). Availability of both preoperative and postoperative CT scans was required for inclusion for further analysis. These images were analyzed on a commercial CT workstation for the volume of lung resected and the pre- and postoperative volume and density of each lung. Expected postoperative densities (preoperative density adjusted for volume) were compared with observed postoperative densities. RESULTS: Review disclosed 583 patients who underwent lobectomy or segmentectomy. Seventeen patients (2.9%) developed postoperative ARDS. Nine of these patients had pre- and postoperative CT scans available for analysis. In eight of nine cases, density increased more in the nonoperated lung than in the operated lung (P =.01). The degree of density increase in the nonoperated lung was significantly greater (305 mg/mL; range, 48-449 mg/mL) than that in the operated lung (13 mg/mL; range, -198 to 231 mg/mL; P <.001). CONCLUSION: Following lobectomy, there appears to be a truly asymmetric form of ARDS rather than compensatory hyperexpansion of the residual lung on the operated side.

Adult↗
PubMed2002

Thin-section CT in obstructive pulmonary disease: discriminatory value.

PURPOSE: To use thin-section computed tomography (CT) to distinguish between causes of obstructive pulmonary disease, to determine which distinctions give rise to diagnostic imprecision, and to identify the most useful CT features. MATERIALS AND METHODS: Thin-section CT scans of 105 patients with obstructive pulmonary disease (asthma, n = 35; centrilobular emphysema, n = 30; panlobular emphysema, n = 21; and obliterative bronchiolitis, n = 19) and 33 healthy subjects were assessed independently by two observers. The most likely diagnosis and a confidence rating were assigned. Individual thin-section CT features were recorded. Accuracy, sensitivity, specificity, negative predictive value, and positive predictive value for first-choice diagnoses were calculated. The prevalence of CT features between pairs of conditions was compared with the chi(2) or Fisher exact test as appropriate. RESULTS: A correct first-choice diagnosis was made in 199 of 276 (72%) observations. A correct first-choice diagnosis was made in 35 of 38 (92%) observations in patients with obliterative bronchiolitis, in 53 of 60 (88%) observations in patients with centrilobular emphysema, in 53 of 66 (80%) observations in healthy subjects, in 37 of 70 (53%) observations in patients with asthma, and in 20 of 42 (48%) observations in patients with panlobular emphysema. The major sources of diagnostic inaccuracy were differentiation between panlobular and centrilobular emphysema, asthma and normality, and asthma and obliterative bronchiolitis. There were significant increases in prevalence of (a) bronchial wall thickening and vascular attenuation in patients with asthma when compared with healthy subjects and (b) vascular attenuation and decreased attenuation in patients with obliterative bronchiolitis when compared with patients with asthma (P <.001). CONCLUSION: CT helps to distinguish diseases that cause airflow obstruction. Thin-section CT is particularly accurate in the identification of obliterative bronchiolitis.

Adolescent↗
PubMed2002

Small-vessel diseases of the lung: CT-pathologic correlates.

Diseases that primarily affect the small vessels of the lung are difficult to diagnose. Many conditions are characterized by involvement of small pulmonary vessels, and pathologically they can be conveniently divided into occluding and inflammatory types. The former, typified by chronic pulmonary thromboembolism and primary pulmonary hypertension, are relatively cryptic in terms of imaging. In contrast, inflammatory vasculitides, which often cause pulmonary hemorrhage and infarction, result in florid but nonspecific radiographic abnormalities. The spectrum of thin-section computed tomographic abnormalities encountered in the inflammatory vasculitides is wide: For example, in Wegener granulomatosis the pattern ranges from cavitating nodules to lobar consolidation to ground-glass opacity. This review highlights some of the less obvious imaging manifestations of occlusive and inflammatory diseases of the small pulmonary vessels.

Adult↗
PubMed2001

Idiopathic interstitial pneumonias: imaging-pathology correlation.

The terminology related to idiopathic interstitial pneumonia (IIP) remains confusing and in some cases wholly inaccurate. In addition, a greater understanding of the correlation between high-resolution computed tomography (HRCT) appearances and the corresponding histopathological changes found in the interstitial pneumonias has resulted in a crucial role for HRCT in the investigation of IIPs. The role of the radiologist is becoming increasingly important with a strong emphasis on establishing a diagnosis without resorting to lung biopsy. We aim to clarify the current classification of the IIPs highlighting their clinical, pathological and imaging characteristics in order to assist the radiologist in performing their increasingly important diagnostic role.

Bronchiolitis↗