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Biomedical subjects

D M Hansell

Publications and source records attributed to D M Hansell.

At least 163 records · Page 9Linked to original sources

The value of negative needle biopsy in suspected operable lung cancer.

The value of needle biopsy (NB) of pulmonary masses in patients unsuitable for surgery is well established. The presence of malignant cells confirms the diagnosis and thus aids management. We have reviewed 196 patients aged over 40 years with a solitary pulmonary mass suspected of being operable lung cancer to assess the effect of a negative NB result on the management. Malignant cells were discovered in 148 patients and diagnoses of infection were made in a further 10. In 38 patients no malignant cells were identified. Nineteen patients proceeded to thoracotomy and 13 of these had malignant disease. Nine others had further needle biopsies and eight of these had malignancy. Ten patients were followed up without any further intervention and four of these eventually proved to have malignancy. Thus of the 38 patients with no malignant cells on NB but no definite benign diagnosis, 25 had malignancy, six had benign disease and seven had presumed benign disease. In this series NB provided a definite benign diagnosis in 5.1% of patients. From this study it may be concluded that if a solitary pulmonary nodule has a high clinical suspicion of malignancy and the patient is a candidate for surgery, NB is of limited value in management.

Adult↗

Digital chest radiology.

With an increasing number of storage phosphor computed radiography units being installed worldwide, the evaluation of digital chest radiology is no longer being confined to experimental determinations of adequate imaging variables. There has been a substantial increase in the number of clinically based studies that have compared computed radiography with conventional film radiography. The applications of computed radiography are widening and further developments in dual-energy imaging and scanning equalization radiography have become possible through the use of phosphor storage computed radiography. Computer-assisted diagnosis applied to chest radiography may shortly be revolutionized by artificial intelligence, which is capable of assimilating both radiographic and clinical data.

Humans↗

Lymphangiomyomatosis: CT, chest radiographic, and functional correlations.

Eight patients with the diagnosis of lymphangiomyomatosis were evaluated with computed tomography (CT), chest radiography, and pulmonary function tests to determine the relationship between the extent of disease seen on imaging studies and functional status. Chest radiographic assessment included the subjective determination of disease extent and measurements of lung length and the arc of the right hemidiaphragm. Disease extent on CT scans was scored as a percentage of lung that was abnormal on the basis of visual assessment of the degree of cystic replacement of the lung parenchyma. Significant correlations were observed between CT scores and percentages of predicted forced expiratory volume in 1 second/forced vital capacity (r = -.92, P less than .002) and diffusing capacity of the lungs for carbon monoxide (r = -.80, P less than .017). No significant correlations were observed between subjective chest radiographic scores and pulmonary function tests, although measurements of lung length and percentage of predicted total lung capacity were correlated (r = .76, P less than .045). CT was more accurate than chest radiography in defining the presence and extent of parenchymal cysts and provided for greater morphologic-physiologic correlation. CT, particularly high-resolution CT, may be useful in the diagnosis and longitudinal evaluation of patients with this disease and may be more sensitive than pulmonary function tests in the early stages of lung damage.

Adult↗

Skeletal abnormalities in Refsum's disease (heredopathia atactica polyneuritiformis).

Refsum's disease is a rare inborn error of phytanic acid metabolism in which skeletal abnormalities are part of the clinical syndrome. The reported incidence of bone changes in patients with Refsum's disease varies widely and reflects the small series published to date. An analysis of the skeletal abnormalities of the largest series of patients in the world is presented.

Adult↗

High-resolution computed tomography in pulmonary cystic fibrosis.

Twenty-one patients with established cystic fibrosis were examined using high-resolution, narrow-section computed tomography. The bronchiectasis of cystic fibrosis is described and is shown to be characteristic in many respects. Computed tomography was found to be more accurate than standard radiography in locating the disease process and demonstrated pleural involvement which was not apparent on chest radiographs.

Adolescent↗

Computed tomography of diffuse lung disease.

The place of computed tomography (CT) scanning in the detection of pulmonary nodules is now well established. Due to the increasing spatial resolution of CT and shorter scan times, patients with diffuse lung disease can now be examined more effectively. Narrow section CT demonstrates the morphological detail of some diffuse lung diseases at an earlier stage than conventional radiography.

Humans↗

The accuracy of mammography alone and in combination with clinical examination and cytology in the detection of breast cancer.

The accuracy of mammography alone and in combination with clinical examination and aspiration cytology was assessed in 402 patients who attended the Early Diagnostic Unit of the Royal Marsden Hospital, London. The sensitivities of mammography, clinical examination and cytology in identifying breast cancer were 76.9%, 81.7% and 63.5% respectively; the specificities of each test were 90.0%, 87.6% and 99.3%. The calculated sensitivity was increased to 96.2% if one positive test out of the three was regarded as an indication to undertake breast biopsy. If this approach was adopted the number of breast cancers missed would be two out of 104 and the yield of positive biopsies would be approximately one in four (27.6%). The implications of proceeding to breast biopsy on the basis of a single positive test are discussed.

Aged↗

A quantitative analysis of the spatial relationships of grouped microcalcifications demonstrated on xeromammography in benign and malignant breast disease.

The mammograms of 444 patients who had a breast biopsy leading to a definitive histological diagnosis were reviewed. In 21 cases (4.7%) grouped microcalcifications were identified as the only mammographic abnormality. These groups of microcalcifications were analysed to determine whether there was any quantitative difference between benign and malignant lesions with respect to a shape parameter of the group, the spatial frequency of the particles and neighbour-to-neighbour relationships of the particles. This analysis did not reveal any significant difference between the spatial relationships of the grouped microcalcifications found in benign and malignant breast disease.

Biopsy↗

Capsular distension and intracapsular pressure in subcapital fractures of the femur.

It has been shown that raised intracapsular pressure causes avascular necrosis of the femoral head in experimental animals, but the relevance of this to clinical fractures of the femoral neck is controversial. We have studied 19 patients with intracapsular fractures of the femoral neck by pressure measurement and by ultrasonography to demonstrate capsular distension. The intra-articular pressure in Garden Grade I and II fractures averaged 66.4 mmHg with a maximum of 145 mmHg. In 10 Garden Grade III and IV fractures the average pressure was 28 mmHg with a maximum of 65 mmHg. Most of the recorded intracapsular pressures were high enough to have caused possible vascular embarrassment, and it is suggested that early decompression of the haemarthrosis should be considered.

Aged↗

A comparison of methods for enhancing the detection of areas of decreased attenuation on CT caused by airways disease.

PURPOSE: The purpose of this work was to investigate thin section CT image enhancement of subtle areas of decreased attenuation of the lung parenchyma in suspected airways disease. METHOD: Forty-seven consecutive patients with chronic sputum production underwent pulmonary function tests and high resolution CT (HRCT). Single section inspiratory (INSP), expiratory (EXP), and minimum intensity projection (MINIP) images through the lower lobes were acquired. A histogram stretch was applied to the INSP and MINIP images, generating two further image formats. The five image types were compared for the extent of decreased attenuation, observer confidence, and correlations with pulmonary function tests. RESULTS: Interobserver variation was lowest with MINIP images (mean weighted K: MINIP 0.70, INSP sections 0.65, other image formats < or =0.48). Observers were most confident with EXP and MINIP images. EXP sections identified more disease than MINIP images (p<0.001). Correlations with pulmonary function tests were similar for each image format. CONCLUSION: The HRCT changes of small airways disease are enhanced with image postprocessing. MINIP images are associated with increased observer confidence and agreement as compared with HRCT alone.

Adult↗

Nitrofurantoin-induced lung disease: two cases demonstrating resolution of apparently irreversible CT abnormalities.

A reticular pattern on high resolution CT (HRCT) invariably represents significant lung pathology and is the dominant feature of irreversible fibrosis. We present two cases of nitrofurantoin-induced pulmonary toxicity in which the initial HRCT showed a widespread reticular pattern and associated distortion of the lung parenchyma, thought to represent established fibrosis. Follow-up HRCT scans after withdrawal of the drug showed resolution of this supposedly irreversible pattern.

Aged↗

Gradient correction and classification of CT lung images for the automated quantification of mosaic attenuation pattern.

PURPOSE: The detection of density differences, or "mosaic attenuation pattern," on CT images may be difficult when the regional inhomogeneity of the density of the lung parenchyma is subtle. The purpose of this work was to develop a fully automated method for the reproducible quantification of the underattenuated areas of the lung parenchyma. This technique may be useful in increasing the precision of investigation of structure/function relationships. METHOD: Anatomical segmentation was achieved by a structure-filtering operator based on mathematical morphology. To compensate for the density gradient visible on lung CT scans, a model-based iterative deconvolution filter and an adaptive clustering algorithm were developed. Validation was performed with CT images from a lung phantom, 15 patients with constrictive obliterative bronchiolitis, and 8 normal subjects. RESULTS: The accuracy of the estimate of the density gradient on phantom studies was 93.3%. The automated quantification of the areas of decreased attenuation on scans of constrictive obliterative bronchiolitis was within 8.2% from the average scoring of two experienced observers. CONCLUSION: The proposed technique is fully automated and can accurately correct for density gradient and classify areas of decreased attenuation on lung CT images.

Bronchiolitis Obliterans↗