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H Page McAdams

Publications and source records attributed to H Page McAdams.

At least 19 recordsLinked to original sources
PubMed2006

Recent advances in chest radiography.

There have been many remarkable advances in conventional thoracic imaging over the past decade. Perhaps the most remarkable is the rapid conversion from film-based to digital radiographic systems. Computed radiography is now the preferred imaging modality for bedside chest imaging. Direct radiography is rapidly replacing film-based chest units for in-department posteroanterior and lateral examinations. An exciting aspect of the conversion to digital radiography is the ability to enhance the diagnostic capabilities and influence of chest radiography. Opportunities for direct computer-aided detection of various lesions may enhance the radiologist's accuracy and improve efficiency. Newer techniques such as dual-energy and temporal subtraction radiography show promise for improved detection of subtle and often obscured or overlooked lung lesions. Digital tomosynthesis is a particularly promising technique that allows reconstruction of multisection images from a short acquisition at very low patient dose. Preliminary data suggest that, compared with conventional radiography, tomosynthesis may also improve detection of subtle lung lesions. The ultimate influence of these new technologies will, of course, depend on the outcome of rigorous scientific validation.

Data Display↗
PubMed2005

Clinical and pathologic features of familial interstitial pneumonia.

RATIONALE: Several lines of evidence suggest that genetic factors and environmental exposures play a role in the development of pulmonary fibrosis. OBJECTIVES: We evaluated families with 2 or more cases of idiopathic interstitial pneumonia among first-degree family members (familial interstitial pneumonia, or FIP), and identified 111 families with FIP having 309 affected and 360 unaffected individuals. METHODS: The presence of probable or definite FIP was based on medical record review in 28 cases (9.1%); clinical history, diffusing capacity of carbon monoxide (DL(CO)), and chest X-ray in 16 cases (5.2%); clinical history, DL(CO), and high-resolution computed tomography chest scan in 191 cases (61.8%); clinical history and surgical lung biopsy in 56 cases (18.1%); and clinical history and autopsy in 18 cases (5.8%). RESULTS: Older age (68.3 vs. 53.1; p < 0.0001), male sex (55.7 vs. 37.2%; p < 0.0001), and having ever smoked cigarettes (67.3 vs. 34.1%; p < 0.0001) were associated with the development of FIP. After controlling for age and sex, having ever smoked cigarettes remained strongly associated with the development of FIP (odds ratio(adj), 3.6; 95% confidence interval, 1.3-9.8). Evidence of aggregation of disease was highly significant (p < 0.001) among sibling pairs, and 20 pedigrees demonstrated vertical transmission, consistent with autosomal dominant inheritance. Forty-five percent of pedigrees demonstrated phenotypic heterogeneity, with some pedigrees demonstrating several subtypes of idiopathic interstitial pneumonia occurring within the same families. CONCLUSIONS: These findings suggest that FIP may be caused by an interaction between a specific environmental exposure and a gene (or genes) that predisposes to the development of several subtypes of idiopathic interstitial pneumonia.

Adult↗
PubMed2005

Comparative scatter and dose performance of slot-scan and full-field digital chest radiography systems.

PURPOSE: To evaluate the scatter, dose, and effective detective quantum efficiency (DQE) performance of a slot-scan digital chest radiography system compared with that of a full-field digital radiography system. MATERIALS AND METHODS: Scatter fraction of a slot-scan system was measured for an anthropomorphic and a geometric phantom by using a posterior beam-stop technique at 117 and 140 kVp. Measurements were repeated with a full-field digital radiography system with and without a 13:1 antiscatter grid at 120 and 140 kVp. For both systems, the effective dose was measured on posteroanterior and lateral views for standard clinical techniques by using dosimeters embedded in a female phantom. The effective DQEs of the two systems were assessed by taking into account the scatter performance and the DQE of each system. The statistical significance of all the comparative differences was ascertained by means of t test analysis. RESULTS: The slot-scan system and the full-field system with grid yielded scatter fractions of 0.13-0.14 and 0.42-0.48 in the lungs and 0.30-0.43 and 0.69-0.78 in the mediastinum, respectively. The sum of the effective doses for posteroanterior and lateral views for the slot-scan system (0.057 mSv +/- 0.003 [+/- standard deviation]) was 34% lower than that for the full-field system (0.086 mSv +/- 0.001, P < .05) at their respective clinical peak voltages (140 and 120 kVp, respectively). The effective DQE of the slot-scan system was equivalent to that of the full-field system in the lung region but was 37% higher in the dense regions (P < .05). CONCLUSION: The slot-scan design leads to marked scatter reduction compared with the more conventional full-field geometries with a grid. The improved scatter performance of a slot-scan geometry can effectively compensate for low DQE and lead to improved image quality.

Phantoms, Imaging↗
PubMed2005

Pulmonary vein diameter, cross-sectional area, and shape: CT analysis.

PURPOSE: To retrospectively establish normal values for pulmonary vein diameter, cross-sectional area, and shape depicted at computed tomography (CT). MATERIALS AND METHODS: Institutional review board waived patient consent requirement and approved the study. Thin-section contrast material-enhanced spiral chest CT scans in 104 patients, 68 women and 36 men (age range, 19-86 years; mean, 49 years) referred to exclude pulmonary embolism, were retrospectively reviewed. Short-axis diameter and cross-sectional area of the four major pulmonary veins (right inferior and superior, left inferior and superior) were measured at a workstation by using oblique reconstructions. Each vein was measured at six locations, 5 mm apart, starting at atrial ostium. Each measurement was performed three times by an experienced thoracic radiologist, and the mean value was recorded. Roundness was estimated by comparing the ratio of the calculated cross-sectional area to that measured. Mixed effects model was used to compare men and women relative to the distribution of diameters and surface areas and to compare roundness of the right and left veins. RESULTS: Mean pulmonary vein diameters at the ostia were variable: right superior, 11.4-12.4 mm; left superior, 9.6-10.5 mm; right inferior, 12.3-13.1 mm; and left inferior, 9.0-9.9 mm. Diameter and cross-sectional area of the left superior pulmonary vein were significantly larger in men than in women (P < .005). As expected, the caliber of three of the four veins gradually increased as they approached the left atrium. Caliber of the left inferior pulmonary vein decreased as it entered the left atrium. None of the veins were round; all were ovoid. Left-sided veins and venous ostia were less round than right-sided veins (P < .001). CONCLUSION: Pulmonary vein diameter, cross-sectional area, and shape vary. Particular care must be taken when the left inferior pulmonary vein is evaluated for stenosis, as it normally narrows as it enters the left atrium.

Adult↗
PubMed2004

Variations in pulmonary venous drainage to the left atrium: implications for radiofrequency ablation.

PURPOSE: To evaluate and classify the various drainage patterns of the pulmonary veins as depicted with thin-section chest computed tomography (CT). MATERIALS AND METHODS: Thin-section (2.5-mm collimation) contrast material-enhanced CT scans of 201 consecutive patients obtained over a 3-month period for diagnosis of pulmonary embolism (n = 197), pulmonary vein stenosis (n = 2), or aortic injury (n = 2) were routinely reviewed in transverse and (if necessary) coronal and coronal-oblique imaging planes. A classification was formulated based on both the number of venous ostia on each side and the drainage patterns of pulmonary veins. The frequency of each pattern was determined, and association with atrial arrhythmia was assessed with the chi(2) and Fisher exact tests. RESULTS: Most patients (n = 142, 71%) had two ostia on the right side for upper and lower lobe veins. Fifty-six patients (28%) had three to five ostia on the right side, which were due to one or two separate middle lobe vein ostia in 52 (26%) patients. Three patients (2%) had a single venous ostium on the right side. Most patients (n = 173, 86%) had two ostia on the left side for upper and lower lobe veins. The remainder (n = 28, 14%) had a single ostium. There was no significant association between any particular venous drainage pattern and atrial arrhythmia; however, patients with a separate ostia for the right middle lobe pulmonary vein(s) tended to have a higher frequency of atrial arrhythmia than those with other patterns (P =.053). CONCLUSION: A classification system to succinctly describe pulmonary venous drainage patterns was developed. Right-sided venous drainage was more variable than left-sided venous drainage. One-quarter of patients had more than two venous ostia on the right side.

Adult↗
PubMed2004

Positron emission tomography with fluoro-2-deoxy-D-glucose (FDG-PET) in the staging of post transplant lymphoproliferative disorder in lung transplant recipients.

Posttransplantation lymphoproliferative disorder (PTLD) is a histologic heterogeneous disease that complicates 4 to 8% of lung transplant recipients. Disease extent is an important prognostic factor and may affect therapy. Positron emission tomography with fluoro-2-deoxy-D-glucose (FDG-PET) has proven useful for staging high-grade lymphomas but is less accurate for staging low-grade and extranodal lymphoma. This study examined our initial experience using FDG-PET imaging to stage lung transplant recipients with posttransplantation lymphoproliferative disorder. FDG can show foci of uptake, particularly in extrathoracic sites, not seen by conventional imaging, which allows more accurate staging of disease thereby yielding useful prognostic information and guiding therapy.

Fluorodeoxyglucose F18↗
PubMed2003

Multiplanar and three-dimensional imaging of the thorax.

Although axial images are sufficient for diagnosis in most instances, knowledge of multiplanar imaging techniques is essential to apply them in appropriate circumstances. In particular, appropriately applied multiplanar imaging adds confidence to interpretations and assists surgeons and bronchoscopists in planning procedures. The need for multiplanar imaging must be assessed before performing any study so that the image acquisition parameters allow for suitable reformations.

Humans↗
PubMed2003

Pulmonary vasculitis: CT features.

The pulmonary vasculitides are a heterogeneous group of inflammatory disorders that may be primarily localized to the pulmonary vasculature or be systemic in nature. The primary pulmonary vasculitides usually affect small vessels, whereas the systemic vasculitides can involve any size pulmonary vessels. For all types of vasculitis, there is a high degree of overlap within groups in regard to their appearance at computed tomography (CT). The most common CT findings are the result of either diffuse or focal pulmonary hemorrhage, are nonspecific, and include ground-glass opacity, consolidation, and small centrilobular nodules. Therefore, the CT findings must be considered in concert with the history, physical examination, and laboratory examination when a specific diagnosis is sought. This review will discuss the typical CT features of both the systemic and the primary pulmonary vasculitides, drawing a distinction where CT is helpful in differentiating among the various causes.

Journal Article↗
PubMed2003

Bronchiolitis obliterans syndrome in lung transplant recipients: correlation of computed tomography findings with bronchiolitis obliterans syndrome stage.

The purpose of this study was to correlate the extent of computed tomographic (CT) findings with the severity of respiratory dysfunction in lung transplant recipients with bronchiolitis obliterans syndrome (BOS). Eighty-nine conventional and 61 thin-section CT scans performed in 44 transplant recipients (17 bilateral, 27 single) with BOS were reviewed for mosaic attenuation, degree of bronchial dilation, bronchial thickening, central and peripheral bronchiectasis, mucus plugging, and air trapping. Findings on conventional and thin-section CT scans were correlated with BOS stage for bilateral and single-lung transplant recipients. In bilateral-lung recipients, a significant correlation existed, although weak, between BOS stage and findings of degree of bronchial dilation (P < 0.01), bronchial wall thickening (P = 0.01), peripheral bronchiectasis (P = 0.01), and mosaic attenuation (P = 0.01) on conventional CT; and bronchial wall thickening (P = 0.01) and mosaic attenuation (P = 0.03) on thin-section CT. In single-lung recipients, BOS stage correlated only with the finding of central bronchiectasis (P = 0.02) on conventional CT scans. No correlation was found between the extent of air trapping and BOS stage in either single- or bilateral-lung transplant recipients. CT findings are relatively poor indices of airflow obstruction in lung transplant recipients with BOS, particularly in those with single-lung transplants for emphysema.

Adolescent↗
PubMed2003

Pleural effusions in lung transplant recipients: image-guided small-bore catheter drainage.

PURPOSE: To assess the efficacy of treating pleural effusions in lung transplant recipients with small-bore catheter drainage. MATERIALS AND METHODS: Chest radiographs and computed tomographic (CT) scans obtained in 31 lung transplant recipients who had pleural effusions treated with catheter drainage were retrospectively reviewed. Duration of drainage and volume of fluid drained were recorded. Results were evaluated 1 and 3 months after chest tube removal. There was complete response (CR) when no pleural fluid remained, partial response (PR) when fluid remaining was less than the pretreatment level, and no response (NR) when fluid recurred to a level at or above the pretreatment level. Associations between cause of effusion (empyema, parapneumonic effusion, rejection, other), response (CR, PR, NR), and type of transplantation (unilateral, bilateral) were examined by using chi2 tests. RESULTS: Of 31 patients, 25 had bilateral effusions; eight of these 25 patients had small-bore catheters inserted bilaterally. Nine patients had multiple sequential catheter insertions. Duration of drainage ranged from 2 to 44 days (median, 6 days). Fluid output was 110-9,726 mL (median, 1,350 mL). One-month follow-up data were available for 31 of 39 treated pleural effusions: 11 (35%) had CR, 18 (58%) had PR, and two (6%) had NR (percentages do not add up to 100% due to rounding). Three-month follow-up data were available for 28 of 39 treated effusions: 22 (79%) had CR, five (18%) had PR, and one (4%) had NR (percentages do not add up to 100% due to rounding). One- and 3-month response rates, respectively, were not related to cause of effusion (P =.82 and.535) or type of transplantation (P =.568 and >.999). CONCLUSION: Small-bore catheter drainage of persistent pleural effusions in lung transplant recipients is usually successful, but drainage is often prolonged and may require multiple catheter placements.

Adolescent↗
PubMed2003

Posttransplant lymphoproliferative disorder: incidence, presentation, and response to treatment in lung transplant recipients.

INTRODUCTION: Posttransplant lymphoproliferative disorder (PTLD) is a relatively infrequent but devastating complication that occurs after solid-organ transplantation. Although the optimal treatment for this condition is unknown, rituximab, a murine/human chimeric monoclonal antibody, has shown promise in the treatment of PTLD. In this report, we define the incidence, clinical features at presentation, and response to treatment of all cases of PTLD observed at our institution over a 10-year period, including four patients who received treatment with rituximab. METHODS: A review of all patients who underwent lung or heart-lung transplant at Duke University from 1992 to 2002 was performed (n = 400), and demographic and clinical outcome data were extracted. RESULTS: PTLD was observed in 10 of 400 patients (2.5%). Patients who acquired PTLD were predominantly > 55 years old (8 of 10 patients) and with a native disease of COPD (7 of 10 patients). Diagnosis of PTLD was made a median of 343 days after transplant. The type of transplant and Epstein-Barr virus (EBV) status prior to transplant did not appear to influence the risk for PTLD. Patients presented with thoracic organ involvement (7 of 10 patients), extrapulmonary disease (2 of 10 patients), or both (1 of 10 patients). Histologic subtypes included polymorphic B cell (n = 4), monomorphic B cell (n = 3), B cell without further classification (n = 2), and anaplastic T cell (n = 1). Only one patient responded to reduced immunosuppression alone. Patients treated with surgery or radiation (n = 2) or rituximab (n = 4) had favorable responses to therapy. Both patients treated with chemotherapy died related to complications of treatment and PTLD. CONCLUSIONS: Presentation and histologic appearance of PTLD varies considerably among lung transplant recipients. PTLD was more frequent among older patients with COPD, regardless of pretransplant EBV serology. Rituximab appears effective as a first-line therapy for PTLD, but additional studies are needed in order to define its efficacy and side effect profile in this population of patients.

Adolescent↗
PubMed2002

High-resolution CT of drug-induced lung disease.

Drug-induced pulmonary toxicity is increasing and early diagnosis is important because of the associated morbidity and mortality. Diagnosis is often difficult and is usually based on a history of drug therapy and exclusion of infection, radiation pneumonitis, and recurrence of the underlying disease. Although HRCT findings are frequently nonspecific, diagnosis can be facilitated by an understanding of the most common histopathologic and radiologic manifestations of drug-induced lung injury and knowledge of the drugs usually involved.

Adult↗
PubMed2002

Drug-induced lung injury.

Lung injury is an increasing cause of morbidity and mortality in patients treated with cytotoxic and noncytotoxic drugs. Prompt diagnosis is important because early drug-induced lung injury will often regress with the cessation of therapy. Diagnosis requires a high index of suspicion because infection, radiation pneumonitis, and recurrence of the underlying disease can manifest clinically and radiologically in a similar manner. Because the lungs have only a limited number of histopathologic responses to injury, including pulmonary edema/diffuse alveolar damage, NSIP, BOOP, EP, and pulmonary hemorrhage, knowledge of these manifestations and the corresponding radiologic manifestations can often be useful in suggesting a diagnosis of drug-induced lung injury. An understanding of the drugs most commonly associated with lung injury can also facilitate diagnosis.

Anti-Infective Agents↗
PubMed2002

Computed tomography diagnosis of macroscopic pulmonary fat embolism.

Pulmonary fat embolism probably occurs commonly after major orthopedic injuries and after orthopedic surgery. Furthermore, tiny fat emboli can often be shown by transesophageal echocardiography during orthopedic surgery. However, large macroscopic are rarely identified radiologically. Macroscopic fat emboli have been previously described in the common femoral vein and inferior vena cava on abdominal imaging. To the authors' knowledge, a macroscopic fat embolus in the pulmonary arteries has not been previously described. The authors report a case of a woman who, on computed tomography, had a large fat embolus after intramedullary rod placement for an isolated left femur fracture.

Adult↗
PubMed2002

Bronchogenic carcinoma after lung transplantation: frequency, clinical characteristics, and imaging findings.

PURPOSE: To determine the frequency, clinical characteristics, and radiologic findings of bronchogenic carcinoma in patients surviving more than 1 month after lung transplantation. MATERIALS AND METHODS: The study population was composed of 2,168 consecutive patients at seven lung transplantation centers who survived longer than 1 month after lung transplantation. Medical records, chest radiographs, and computed tomographic (CT) scans obtained at the time of diagnosis and prior images when available were reviewed for various items of information and imaging features. RESULTS: Twenty-four (1%) of the 2,168 patients, all with single-lung transplants, developed cancer in the native lung. Eighteen patients had emphysema, and six had pulmonary fibrosis. The frequencies of cancer in patients with emphysema and fibrosis were 2% (18 of 859 patients) and 4% (six of 147 patients), respectively. Twelve (50%) of their 24 cancers were detected at chest radiography. Fourteen (58%) patients had clinical symptoms. Twenty-one (88%) of the 24 patients had one (n = 11) or more (n = 10) nodules, and nine (38%) had one (n = 8) or more (n = 1) masses visible on CT scans. Nodules and masses were visible on 12 (50%) and seven (29%) of 24 chest radiographs, respectively. Eleven (48%) of 23 cancers for which prior chest radiographs were available were seen retrospectively on prior chest radiographs. CONCLUSION: Bronchogenic carcinoma develops in the native lung of transplant recipients with emphysema and pulmonary fibrosis with frequencies of 2% and 4%, respectively. The carcinomas most commonly manifest as a pulmonary nodule or mass on chest radiographs, with more nodules seen on CT scans.

Aged↗
PubMed2002

Progression of idiopathic pulmonary fibrosis in native lungs after single lung transplantation.

This retrospective, single-center study was conducted to assess the response of native idiopathic pulmonary fibrosis (IPF) lungs to a potent cyclosporine-based immunosuppressive regimen in single-lung transplantation recipients. The study included IPF patients who had undergone single-lung transplantation and had chest CT scans before and after transplantation. Five patients underwent single-lung transplantation for IPF between April 1992 and January 2001, and met entry criteria. All patients were placed on an immunosuppressive regimen consisting of prednisone, azathioprine, and cyclosporine. In two of the five patients, ground glass attenuation in the native IPF lung improved post-transplantation. However, fibrotic changes progressed in all five patients. In patients with advanced IPF, a potent cyclosporine-based immunosuppressive regimen is not likely to have an effect on the progression of the disease.

Disease Progression↗
PubMed2002

Relapsing polychondritis affecting the lower respiratory tract.

OBJECTIVE: The purpose of this study was to describe the CT findings of lower respiratory tract involvement by relapsing polychondritis. CONCLUSION: The most common CT manifestations were increased attenuation and smooth thickening of airway walls. Tracheal or bronchial stenosis was less common. Airway collapse and lobar air trapping were seen in half of patients examined with expiratory CT.

Adult↗