Biomedical subjects

G McGuinness

Publications and source records attributed to G McGuinness.

At least 37 records · Page 2Linked to original sources

PubMed1996

The relation of maternal complications to outcomes in very low birthweight infants in an era of changing neonatal care.

We examine the relation of key neonatal outcomes to pregnancy complications and to the use of antenatal steroids and investigate whether there is evidence of recent change in this relation. Complete information on pregnancy and neonatal course was available for 749 out of 949 singleton births without major congenital anomalies below 1501 g admitted to seven regional neonatal intensive care units between August 1, 1988 and June 30, 1991. Mortality was highest in infants born after labor with spontaneous rupture of fetal membranes of less than 24 hours duration (odds ratio [OR] = 1.6, 95% confidence interval [1.0, 2.6]). Spontaneous rupture of membranes of over 24 hours duration was associated with decreased risk of respiratory distress syndrome (OR = 0.42, [0.28, 0.64]) and decreased risk of patent ductus arteriosus (OR = 43, [0.28, 0.66]). Pregnancy induced hypertension was associated with increased risk of respiratory distress syndrome in those born at less than 20 weeks' gestation (OR = 6.0, [2.0, 17]). Labor with or without rupture of membranes of short duration was associated with increased risk of intraventricular hemorrhage (OR = 1.9, [1.2, 2.5]). These associations were not different in early versus late time periods of the study. Antenatal steroids were associated with dramatically reduced risk of mortality (OR = 0.20, [0.09, 0.50] ), respiratory distress syndrome (OR = 0.52, [0.32, 0.85]), and intraventricular hemorrhage (OR = 0.37, [0.21-0.65]).

Adrenal Cortex Hormones↗

PubMed1996

Differentiation of the ILO boundary chest roentgenograph (0/1 to 1/0) in asbestosis by high-resolution computed tomography scan, alveolitis, and respiratory impairment.

High-resolution computed tomography (HRCT) scans have been advocated as providing greater sensitivity in detecting parenchymal opacities in asbestos-exposed individuals, especially in the presence of pleural fibrosis, and having excellent inter- and intraobserver reader interpretation. We compared the 1980 International Labor Organization (ILO) International Classification of the Radiographs of the Pneumoconioses for asbestosis with the high-resolution CT scan using a grid scoring system to better differentiate normal versus abnormal in the ILO boundary 0/1 to 1/0 chest roentgenograph. We studied 37 asbestos-exposed individuals using the ILO classification, HRCT grid scores, respiratory symptom questionnaires, pulmonary function tests, and bronchoalveolar lavage. We used Pearson correlation coefficients to evaluate the linear relationship between outcome variables and each roentgenographic method. The normal HRCT scan proved to be an excellent predictor of "normality," with pulmonary function values close to 100% for forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), total lung capacity (TLC), and carbon monoxide diffusing capacity (DLCO) and no increase in BAL inflammatory cells. Concordant HRCT/ILO abnormalities were associated with reduced FEV1/FVC ratio, reduced diffusing capacity, and alveolitis consistent with a definition of asbestosis. In our study, the ILO classification and HRCT grid scores were both excellent modalities for the assessment of asbestosis and its association with impaired physiology and alveolitis, with their combined use providing statistical associations with alveolitis and reduced diffusing capacity.

Asbestosis↗

PubMed1996

Diffuse lung disease: assessment with helical CT--preliminary observations of the role of maximum and minimum intensity projection images.

PURPOSE: To evaluate assessment of diffuse lung disease with helical computed tomography (CT) and maximum intensity projection (MIP) and minimum intensity projection images. MATERIALS AND METHODS: Six patients with suspected lung disease (the control group) and 20 patients with documented disease underwent axial helical CT through the upper and lower lung fields. Findings on the MIP and minimum intensity projection images of each helical data set were compared with findings on the thin-section scan obtained at the midplane of the series. RESULTS: Owing to markedly improved visualization of peripheral pulmonary vessels (n = 26) and improved spatial orientation, MIP images were superior to helical scans to help identify pulmonary nodules and characterize them as peribronchovascular (n = 2) or centrilobular (n = 7). Minimum intensity projection images were more accurate than thin-section scans to help identify lumina of central airways (n = 23) and define abnormal low (n = 15) and high (ground-glass) (n = 8) lung attenuation. Conventional thin-section scans depicted fine linear structures more clearly than either MIP or minimum intensity projection images, including the walls of peripheral, dilated airways (n = 3) and interlobular septa (n = 3). MIP and minimum intensity projection images added additional diagnostic findings to those on thin-section scans in 13 (65%) of 20 cases. CONCLUSION: MIP and minimum intensity projection images of helical data sets may help diagnosis of a wide spectrum of diffuse lung diseases.

Adult↗

PubMed1996

Disease progression in usual interstitial pneumonia compared with desquamative interstitial pneumonia. Assessment with serial CT.

OBJECTIVE: To determine the outcome of areas of ground-glass attenuation and assess disease progression on serial high-resolution CT (HRCT) scans of patients with biopsy specimen-proved usual interstitial pneumonia (UIP) and desquamative interstitial pneumonia (DIP). MATERIALS AND METHODS: Twelve patients with biopsy specimen-proved UIP and 11 patients with biopsy specimen-proved DIP who had initial and follow-up HRCT scans (median interval, 10 months) were reviewed. Eleven patients with UIP and 11 with DIP received treatment between the initial and follow-up CT scans. The scans were evaluated for the presence and extent of ground-glass attenuation, irregular linear opacities and honeycombing, and overall extent of parenchymal involvement. RESULTS: On initial CT scans, all 12 patients with UIP had areas of ground-glass attenuation (mean +/- SD extent, 30 +/- 16%) and irregular lines (mean +/- SD extent, 17 +/- 7%) and 10 patients had honeycombing (mean +/- SD extent, 10 +/- 6%). All 11 patients with DIP had areas of ground-glass attenuation on initial HRCT scans (mean +/- SD extent, 51 +/- 26%), 5 patients had irregular linear opacities (mean +/- SD extent, 5 +/- 5%), and 1 patient had honeycombing. Nine of the 12 patients with UIP showed increase in the extent of ground-glass attenuation (n = 6) or progression to irregular lines (n = 2) or honeycombing (n = 4) on follow-up as compared with only 2 patients with DIP who showed progression to irregular lines (n = 1) or honeycombing (n = 1) (p < 0.01 chi 2 test). CONCLUSION: In patients with UIP, areas of ground-glass attenuation usually increase in extent or progress to fibrosis despite treatment. Areas of ground-glass attenuation in most patients with DIP remain stable or improve with treatment.

Adult↗

PubMed1996

Detection and differential diagnosis of pulmonary infections and tumors in patients with AIDS: value of chest radiography versus CT.

OBJECTIVE: The purpose of this study was to compare the sensitivity and specificity of chest radiography with those of CT in the detection of pulmonary infections and tumors in patients with AIDS. MATERIALS AND METHODS: The study was retrospective and included the radiographs and CT scans of 139 patients. Eighty-nine had one proven thoracic complication, 17 had two proven thoracic complications, and 33 had no active intrathoracic disease at the time of the examinations. The radiographs and CT scans were interpreted blindly by two independent observers from different institutions. The observers assessed for the presence or absence of intrathoracic disease and recorded the most likely diagnosis and the degree of confidence in that diagnosis. RESULTS: The patients were more commonly correctly identified as having or not having intrathoracic disease on the basis of CT findings than on the basis of radiographic findings ( p < .01, chi-square test). Of the 106 patients with intrathoracic complications, 90% (191 of 212 interpretations) were correctly identified by the two observers on the radiograph and 96% (204 of 212 interpretations) at CT. Of 33 patients without intrathoracic disease, 73% (48 of 66 interpretations) were correctly identified at radiography and 86% (57 of 66 interpretations) at CT. Of 89 patients with one proved thoracic complication, the observers confident in their first-choice diagnosis in 34% of the cases (61 of 178 interpretations) at chest radiography and in 47% (83 of 178 interpretations) at CT. This diagnosis was correct in 67% (41 of 61) of confident radiographic interpretations as compared with 87% (72 of 83) of interpretations at CT (p < .01, chi-square test). CONCLUSION: CT is superior to chest radiography in allowing identification of patients with and without thoracic disease and in the differential diagnosis of pulmonary complications of patients with AIDS. However, the improvement in differential diagnosis is modest. Because in most cases the radiographs and CT scans were obtained as part of the clinical evaluation, the study is probably biased toward problematic clinical cases. In the majority of patients, the chest radiograph provides adequate information and CT is not warranted.

AIDS-Related Opportunistic Infections↗

PubMed1996

Subjective pitfalls in HRCT interpretation.

High-resolution computed tomography (HRCT) allows a detailed assessment of the anatomy and pathology of the pulmonary parenchyma. However, numerous potential pitfalls exist that can hinder or preclude accurate interpretation of HRCT images. These sources of potential diagnostic error can be systematically evaluated with respect to the major categories of HRCT abnormalities: (1) increased parenchymal attenuation, (2) linear opacities and interstitial disease, (3) nodular lung disease, and (4) holes in the lung. Accurate HRCT interpretation depends on the correct recognition and characterization of imaging abnormalities. Technical factors that enhance or limit scan interpretation, HRCT features of subtle disease, and imaging mimics of commonly observed pathology are addressed in detail with regard to each of the above categories of disease. Common pitfalls are illustrated and explained in an effort to increase general awareness of these sources of real and potential diagnostic confusion.

Humans↗

PubMed1995

Bronchiectasis: CT/clinical correlations.

The association between bronchiectasis and human immunodeficiency virus infection, the resurgence of tuberculosis, especially in urban and immunocompromised patients, and the recognition of bronchiectasis as a manifestation of rejection in the transplant population are emerging clinical settings in which establishing the diagnosis of bronchiectasis is becoming increasingly important. High-resolution CT, by virtue of its well-established accuracy, is currently accepted as the optimal noninvasive means of diagnosing bronchiectasis. However, reliable diagnosis requires meticulous attention to technique and a thorough knowledge of potential pitfalls. These include, among others, respiratory and cardiac motion artifacts as well as effects of collimation and electronic windowing. It also is important to recognize diseases that may mimic the appearance of bronchiectasis as well as unusual manifestations of bronchiectasis that may obscure the diagnosis.

Acquired Immunodeficiency Syndrome↗

PubMed1995

Unusual lymphoproliferative disorders in nine adults with HIV or AIDS: CT and pathologic findings.

PURPOSE: To identify characteristic computed tomographic (CT) findings in unusual pulmonary lymphoproliferative disorders seen in adults with the human immunodeficiency virus (HIV) or acquired immunodeficiency syndrome (AIDS). MATERIALS AND METHODS: The authors retrospectively reviewed the CT scans and pathologic specimens from nine patients with pulmonary lymphoproliferative disorders. CT scans were evaluated for nodules, reticulation, areas of ground-glass attenuation, consolidation, and bronchial disease. Changes seen in pathologic specimens were classified as consistent with classic lymphocytic interstitial pneumonitis (LIP), mucosa-associated lymphoid tissue lymphoma (MALTOMA), or atypical lymphoproliferative disorder (ALD). Immunopathologic results were reviewed when available. RESULTS: Eight patients had AIDS. Five patients had classic LIP. One patient had MALTOMA, and three patients had ALD. Altogether, 2-4-mm-diameter nodules were the predominant CT finding in eight patients; these were peribronchovascular in four patients. The presence of interstitial nodules correlated with the pathologic finding of nodular disease in seven patients. CONCLUSION: Familiarity with these AIDS-related disorders and their CT appearance should assist in the differential diagnosis.

Acquired Immunodeficiency Syndrome↗

PubMed1995

Bacillary angiomatosis in patients with AIDS: multiorgan imaging findings.

PURPOSE: To describe the varied clinical manifestations and imaging findings encountered in bacillary angiomatosis, an infectious complication of the acquired immunodeficiency syndrome (AIDS). MATERIALS AND METHODS: Clinical, imaging, and histopathologic findings in nine men (aged 26-50 years) with AIDS and bacillary angiomatosis were described. This condition often manifests as vascular skin lesions that resemble those of Kaposi sarcoma, fever, and anemia and is due to infection with Bartonella (Rochalimaea) henselae. RESULTS: Common imaging findings included lung nodules, mediastinal adenopathy, peripheral adenopathy, pleural effusions, ascites, abdominal adenopathy, soft-tissue masses, and low-attenuation lesions in the liver and/or spleen. Most notably, nodes and soft-tissue lesions were dramatically enhanced with injection of contrast material, which is presumably because the lesions are composed to a large extent of well-formed capillaries. CONCLUSION: Bacillary angiomatosis, a treatable infection, should be considered in patients with AIDS, particularly when Kaposi sarcoma is suspected clinically.

Acquired Immunodeficiency Syndrome↗

PubMed1995

Perinatal transmission and maternal risks of human papillomavirus infection.

We conducted a prospective study to investigate whether human papillomavirus (HPV) could be vertically transmitted to neonates. Pregnant women (N = 203) were tested for HPV DNA infection during the third trimester and again during labor prior to delivery. Their newborns (N = 203) were tested 1 to 3 days after delivery. Among the mothers, 12.3% (N = 25/203) typed HPV positive at either or both maternal specimen collection periods, whereas only 1.0% of the neonates (N = 2/203) typed positive. This low transmission rate may be due in part to the fact that 65% of mothers who were HPV positive during the third trimester tested HPV negative by labor/delivery. The higher frequency of risks associated with maternal HPV infection were similar to those found in studies of cervical dysplasia and cancer: younger age at first intercourse and first pregnancy, number of sexual partners, and longer duration in use of oral contraceptives. In addition, those who were past smokers and had a shorter recency and latency period in smoking were more likely to be detected with HPV.

Adolescent↗

PubMed1994

A population study. Mortality and morbidity after availability of surfactant therapy. Newborn Lung Project.

OBJECTIVE: To assess the impact of recent changes in neonatal intensive care on the mortality and morbidity of very-low-birth-weight neonates (< 1501 g). DESIGN: Prospective cohort study. SETTING: Six neonatal intensive care units in Wisconsin and Iowa. PARTICIPANTS: All very-low-birth-weight neonates who were admitted to the neonatal intensive care units the year before the availability of exogenous surfactant (n = 333), during the investigational new drug protocol for synthetic surfactant (Exosurf) (n = 347), and after the release of synthetic surfactant (n = 356) (designated as periods 1, 2, and 3, respectively). INTERVENTIONS: None. MAIN RESULTS: The percentage of neonates receiving exogenous surfactant in the three periods was 3%, 37%, and 56%, and the percentage receiving antenatal steroids was 12%, 17%, and 27% (P = .0001 for increase in both modalities). The percentage of neonates dying in the three periods was 23%, 14%, and 19% (P = .05 for downward trend). The percentage of neonates with intraventricular hemorrhage decreased in the subgroup weighing between 700 and 1350 g (35%, 28%, and 24%) (P = .04) and increased in the subgroup weighing below 700 g (8%, 41%, and 45%) (P = .03). The percentage of neonates with bronchopulmonary dysplasia increased from 21% to 36% between periods 1 and 2 (P = .003) and decreased to 27% (P = .04) in period 3. Antenatal steroid use was strongly associated with the decrease in intraventricular hemorrhage (odds ratio, 0.35) and mortality risk (odds ratio, 0.20). CONCLUSIONS: Several developments in care have contributed to changes in mortality risk, incidence of intraventricular hemorrhage, and the severity of respiratory disease in very-low-birth-weight infants.

Hospital Mortality↗

PubMed1994

Keratinocyte growth factor and fibroblast growth factor action on DNA synthesis in rat and human hepatocytes: modulation by heparin.

Keratinocyte growth factor (KGF/FGF-7) is a member of the fibroblast growth factor (FGF) superfamily. Unlike other members of the family, the biological activity of KGF appears to be restricted to epithelial cells. Here we have tested the activity of KGF, acidic fibroblast growth factor (aFGF), and basic fibroblast growth factor (bFGF) on normal adult rat and human hepatocytes and their modulation by heparin. Although more modest than the growth response to epidermal growth factor (EGF) and hepatocyte growth factor (HGF), recombinant KGF enhanced DNA synthesis in rat hepatocytes by two- to threefold. This stimulation occurred in the absence of serum and of other exogenous growth factors. Addition of heparin inhibited the KGF response. Although basic FGF showed little activity on rat hepatocytes, acidic FGF stimulated DNA synthesis by approximately twofold and was substantially enhanced by heparin. In contrast to rat cells, human hepatocytes consistently failed to respond to KGF, aFGF, or bFGF with or without heparin, under conditions where EGF and HGF stimulated DNA synthesis up to sixfold. These results indicate that KGF is capable of acting as a complete mitogen for rat hepatocytes in culture and that the activity is consistent with expression by these cells of a type II FGF receptor subtype, the KGF receptor. These observations suggest that KGF/aFGF together with proteoglycans may help regulate rat but not human liver growth.

Adult↗

PubMed1994

Cytomegalovirus pneumonitis: spectrum of parenchymal CT findings with pathologic correlation in 21 AIDS patients.

PURPOSE: To identify characteristic features of cytomegalovirus (CMV) pneumonitis at computed tomography (CT), particularly markers that may help differentiate CMV from Pneumocystis carinii pneumonia. MATERIALS AND METHODS: Bronchoalveolar lavage (BAL) and biopsy results in 21 patients with acquired immunodeficiency syndrome, cytopathologic evidence of CMV infection without other infections, and available CT scans were retrospectively evaluated. CT findings were correlated with radiographic and pathologic findings when available. RESULTS: BAL findings were positive for CMV in only six cases, 13 patients had extrathoracic CMV infection, and 10 had Kaposi sarcoma. CT findings included ground-glass attenuation, dense consolidation, bronchial wall thickening or bronchiectasis, and interstitial reticulation without air-space disease (12 patients had discrete pulmonary nodules or masses). Biopsy revealed air-space disease as the dominant process in eight cases. Histopathologic findings correlated well with CT appearances. CONCLUSION: CMV pneumonitis should be suspected in patients with either extrathoracic CMV or documented Kaposi sarcoma, especially when radiographic or CT evidence of pulmonary nodules or masses exists.

AIDS-Related Opportunistic Infections↗

PubMed1994

Hemoptysis: prospective high-resolution CT/bronchoscopic correlation.

The precise roles of fiberoptic bronchoscopy (FOB) and computed tomography (CT) of the chest in the evaluation of patients presenting with hemoptysis have not been clearly defined. On the assumption that both procedures would likely provide unique and complementary information, a prospective study with blinded interpreters using a modified high-resolution CT technique (HRCT) and FOB was designed to evaluate 57 consecutive patients admitted to Bellevue Hospital with hemoptysis. Etiologies included bronchiectasis (25 percent), tuberculosis (16 percent), lung cancer (12 percent), aspergilloma (12 percent), and bronchitis (5 percent): in an additional 5 percent of cases, hemoptysis proved to be due miscellaneous causes, while in 19 percent hemoptysis proved to be cryptogenic. Patients with lung cancer all were at least 50 years old, smoked an average of 78 pack-years, and had less severe hemoptysis but of longer duration. All had conditions diagnosed both by HRCT and FOB. High-resolution CT proved of particular value in diagnosing bronchiectasis and aspergillomas, while FOB was diagnostic of bronchitis and mucosal lesions such as Kaposi's sarcoma. Fiberoptic bronchoscopy localized bleeding in only 51 percent of cases. The high sensitivity of CT in identifying both the intraluminal and extraluminal extent of central lung cancers in conjunction with its value in diagnosing bronchiectasis suggest that CT should be obtained prior to bronchoscopy in all patients presenting with hemoptysis.

Adult↗

PubMed1993

Variables affecting pulmonary nodule detection with computed tomography: evaluation with three-dimensional computer simulation.

To meaningfully evaluate factors determining the overall accuracy of computed tomography (CT) for identifying pulmonary nodules, computer-generated nodules were superimposed on normal CT scans and interpreted independently by three experienced chest radiologists. Variables evaluated included nodule size, shape, number, density, location, edge characteristics, and relationship to adjacent vessels, as well as technical factors, including slice thickness and electronic windowing. The overall sensitivity in identifying nodules was 62% and the specificity was 80%. On average, the observers identified 56, 67, and 63% of nodules on 1.5-, 5-, and 10-mm-thick sections, respectively (p = 0.037). Nodules were more difficult to identify on 1.5-mm-thick sections. On average, observers identified 1, 48, 82, and 91% of nodules < 1.5, < 3, < 4.5, and < 7 mm in diameter, respectively (p < 0.001). Other factors that made a significant contribution (p < 0.01) in identifying nodules, as determined by linear discriminant function analysis, included nodule location, angiocentricity, and density. We concluded that computer-generated nodules can be used to assess a large number of imaging variables. We anticipate that this approach will be of considerable utility in assessing the accuracy of interpretation of a wide range of pathologic entities as well as in optimizing three-dimensional scan protocols within the thorax.

Humans↗

PubMed1993

Desquamative interstitial pneumonia: thin-section CT findings in 22 patients.

To evaluate the findings on thin-section computed tomographic (CT) scans in desquamative interstitial pneumonia (DIP), the CT scans from 22 patients aged 22-71 years (mean age, 43 years) were reviewed. In all patients, DIP was proved with open-lung biopsy performed 1 day to 17 months before or after examination with CT (median interval, 1.5 months). The lungs were divided into three zones (upper, middle, and lower); each zone was evaluated separately. The predominant finding was the presence of areas of ground-glass attenuation that involved the middle and lower lung zones in all patients and the upper lung zones in 18 patients (82%). Such areas had a lower lung zone predominance in 16 patients (73%) and a predominantly peripheral distribution in 13 patients (59%). Irregular lines of attenuation suggestive of fibrosis were seen in 11 patients (50%) and cystic changes, in seven patients (32%). The distribution of abnormalities in DIP is similar to that seen in usual interstitial pneumonia (UIP), but the greater extent of ground-glass attenuation and the paucity of cystic changes in DIP should enable distinction from UIP in most patients.

Adult↗

PubMed1993

Accessory cardiac bronchus: CT features and clinical significance.

PURPOSE: The accessory cardiac bronchus is a rare congenital anomaly of the tracheobronchial tree that arises from the medial wall of the bronchus intermedius. This report documents the computed tomographic (CT) appearance of this anomaly. MATERIALS AND METHODS: Six patients with this anomaly were identified. All six underwent CT; three underwent correlative bronchoscopy, and one had both bronchoscopic and surgical confirmation. RESULTS: In all six cases, a distinct airway could be identified originating from the medial wall of the bronchus intermedius. Associated lung parenchymal tissue was identified in four cases, while in three cases a discrete soft-tissue mass was seen, presumably representing vascularized bronchial or vestigial parenchymal tissue. In two cases, the lumen of the airway was filled with debris. CONCLUSION: Recognition of this anomaly is important, as associated clinical complications, including recurrent episodes of both infection and hemoptysis, may be anticipated in a small percentage of patients.

Adult↗

PubMed1993

Bronchiectasis: CT evaluation.

CT is the imaging method of choice after standard chest radiography for examining patients with suspected bronchiectasis. In most institutions throughout the world, CT has largely eliminated the need for bronchography in the diagnosis of bronchiectasis. Nonetheless, controversy persists concerning the overall accuracy of CT. In an effort to improve overall diagnostic accuracy, we review the wide range of CT appearances of this protean disorder, and emphasize potential problems and technical pitfalls that may arise in routine clinical imaging.

Bronchiectasis↗