Emphysema in silica- and asbestos-exposed workers seeking compensation. A CT scan study.

It has been established that coal pneumoconiosis and confluent silicosis are associated with emphysematous changes in the lungs. In the present study, we addressed the concept of emphysema in simple silicosis and asbestosis and in workers exposed to these minerals without the pneumoconiosis. The study was done on 207 consecutive workers evaluated for possible pneumoconiosis at Québec Workman Compensation Board, who had a radiographic reading of pneumoconiosis in the category 0 or 1 of the ILO scale, and in 5 control subjects. Emphysema was detected, typed, and graded on high-resolution CT scans by three independent experienced readers. Age, work experience and industry, smoking habits, and pulmonary function test results were analyzed for possible associations. The subjects were 59 +/- 1 years of age and had mineral dust exposure averaging 26 +/- 1 years; 31 were lifetime nonsmokers and the others were either ex- or current smokers. Ninety-six workers were from primary and 111 from secondary industries and did not differ in any parameter. The CT scan readings for emphysema yielded a 63% complete agreement. In lifetime non-smokers, emphysema was seen in 1 of 20 subjects without pneumoconiosis but in 8 of 11 patients with pneumoconioses. In smokers without pneumoconioses, emphysema was present in 55% of patients with silica exposure, but 29% of patients with asbestos exposure but comparable smoking (p = 0.04). Emphysema type was equally distributed among the groups except for more paracicatricial type in confluent silicosis. Regression analyses documented that age, smoking, exposure type, and presence of pneumoconiosis were significant contribution factors. In the workers without pneumoconiosis, age, smoking, and exposure type (silica) were significant. Emphysema related best with FEV1/FVC ratio, MMEF, and DCO reductions. The prevalence of abnormality of FEV1/FVC ratio was two to five times normal and that of reduced DCO two times normal. We conclude that, in our population, there was a significant excess of CT scan emphysema, associated with lung dysfunction, in those with pneumoconioses and in smokers with silica exposure. In the absence of smoking, it took a patient with pneumoconiosis to have emphysema. These changes contributed to the lung function impairment of these subjects with ILO category 0 or 1 pneumoconioses.

Endoscopic removal of a right lower lobe bronchial lipoma in a high-risk patient: a case report.

Endobronchial lipomas are rare benign tumours that cause bronchial obstruction, leading to extensive distal parenchymal damage. This report describes the endoscopic removal of a right main bronchus lipoma with a rigid endoscope and snare technique in a high-risk patient. The patient was successfully treated without complication. Endoscopic reaction is the preferred therapeutic approach for this subgroup of patients.

Computed tomography in the early detection of asbestosis.

Computed tomography (CT; both conventional (CCT) and high resolution (HRCT)) scans of the thorax were evaluated to detect early asbestosis in 61 subjects exposed to asbestos dust in Québec for an average of 22(3) years and in five controls. The study was limited to consecutive cases with chest radiographs of the International Labour Organisation categories 0 or 1 determined independently. All subjects had a standard high kilovoltage posteroanterior and lateral chest radiograph, a set of 10-15 1 cm collimation CCT scans and a set of three to five 2 mm collimation HRCT scans in the upper, middle, and lower lung fields. Five experienced readers independently read each chest radiograph and sets of CT scans. On the basis of three to five readers agreeing for small opacities of the lung parenchyma, 12/46 (26%) negative chest radiographs were positive on CT scans, but 6/18 (33%) positive chest radiographs were negative on CT scan. On the basis of four to five readers agreeing on a chest radiograph, 36/66 (54%) subjects were normal (group A), 17/66 (26%) were indeterminate (group B), and 13/66 (20%) were abnormal (group C). By the combined readings of CCT and HRCT, 4/31 (13%) asbestos exposed subjects of group A were abnormal (p < 0.001), 6/17 (35%) of group B were abnormal, and in group C, 1/13 (8%) was normal, 2/13 were indeterminate, and 10/13 (77%) were abnormal. Separate readings of CCT and HRCT on distinct films in 14 subjects showed that all cases of asbestosis were abnormal on both CCT and HRCT. Inter-reader analyses by kappa statistics showed significantly better agreement for the readings of CT than the chest radiographs (p < 0.001), and for the reading of CCT than HRCT (p < 0.01). Thus CT scans of the thorax identifies significantly more irregular opacities consistent with the diagnosis of asbestosis than the chest radiograph (20 cases on CT scans v 13 on chest radiographs when four to five readers agreed, 13% of asbestos exposed subjects with normal chest radiographs or 21% of asbestos exposed subjects with normal or near normal chest radiographs. It decreased the number of indeterminate cases significantly from 17 on chest radiographs to 13 on CT scans. All cases of asbestosis detected only on CT scans were similarly seen on CCT and HRCT and did not have significant changes in lung function. The CT scans significantly reduced the inter-reader variability, despite the absence of ILO type reference films for these scans.

MR imaging of superior sulcus carcinoma.

Magnetic resonance (MR) imaging was performed in 10 patients with biopsy proven superior sulcus carcinomas to determine the extent of local tumor invasion. Chest wall invasion or extension into the base of the neck was demonstrated in five patients. This finding was facilitated by the contrast between the bright signal intensity of tumor and the low signal intensity of muscle on T2-weighted images. In three patients, MR clearly depicted direct invasion of the mediastinum. This finding was facilitated on the MR image because of inherent contrast between the mediastinal fat and tumor. Coronal and sagittal images showed the relationship of tumor to the subclavian artery and brachial plexus in all cases. Encasement of the artery was confirmed in two cases and brachial plexus involvement in three. However, MR failed to detect evidence of rib destruction in five patients in whom rib involvement was confirmed by other studies. Magnetic resonance appears to be a useful imaging modality in determining the extent of local disease and, therefore, the selection of patients for surgical resection. Multiplanar imaging and contrast between tumor and muscle and tumor and fat allow assessment of invasion of the mediastinum and base of the neck, subclavian artery, and brachial plexus.

Urinary tract dilatation in utero: classification and clinical applications.

A morphologic classification of in utero urinary tract dilatation is presented. Ninety-two hydronephrotic fetal kidneys diagnosed with ultrasound were graded according to the proposed classification. The findings suggest that grade I dilatation (anteroposterior diameter of the renal pelvis less than 10 mm) should be considered normal. Grades II and III constitute an intermediate hydronephrosis, requiring postnatal urologic surgery in nearly half the cases. Grade IV (moderate dilatation of the calyces, with easily identified residual renal cortex) and grade V (severe dilatation of the calyces with atrophic cortex) are clearly pathologic and require neonatal corrective surgery. It is hoped that use of this simple and practical classification will facilitate communication and comparison of results in the literature.

Ureteropelvic junction stenosis: antenatal ultrasonographic diagnosis, postnatal investigation, and follow-up.

Between January 1981 and October 1984, the diagnosis of ureteropelvic junction (UPJ) stenosis was suspected in 39 fetuses after routine obstetrical ultrasound (US) examination. Postnatal investigation revealed that the initial diagnosis had been accurate in 30 cases (77%). There were 35 UPJ stenoses in 30 patients. The degree of dilatation of the renal pelvis (grades III, IV, or V) observed postnatally with sonography as well as the obstructive excretory pattern noted by renal isotope scanning were used as criteria to determine the need for early postnatal pyeloplasty (performed in 25 patients), which relieved the obstruction and, in the majority of patients, improved renal structure and function.

Renal cell carcinoma presenting as multilocular cystic mass.

We report a case of a multilocular cystic mass that was erroneously labeled multilocular cystic nephroma at ultrasound and computerized tomography, thus leading to a partial nephrectomy; however the final histologic diagnosis was a multilocular cystic renal cell carcinoma. Only 1 similar case has been reported previously. The radiologic and surgical implications are discussed.

[Necrotic enteritis in broiler chickens. III. Study of the factors favoring the multiplication of Clostridium perfringens and the experimental transmission of the disease]. / Entérite nécrotique chez le pollet de gril III. Etude des facteurs favorisant la multiplication de Clostridium perfringens et la transmission expérimentale de la maladie

Necrotic enteritis was reproduced experimentally in two week old broiler chickens by intravenous injection and also by oral administration of a pure culture of Clostridium perfringens. In the first experiment, gross and microscopic intestinal lesions, typical of necrotic enteritis, were observed in all diseased birds and mortality was obtained only in the group of birds that were injected with 0.4 ml or more of the pure culture of the microorganism. In the second experiment, the highest mortality was noted in the group of birds that received orally, in addition to the Clostridium culture, a solution of sodium bicarbonate, to obtain an alkaline intestinal content and opium to decrease the intestinal peristaltism. The gross and microscopie intestinal lesions of the diseased and killed birds were more severe than those observed in the other groups and were similar to those encountered in field outbreaks of necrotic enteritis.

[Necrotic enteritis in broilers. II. Characteristics of the strains of Clostridium perfringens isolated]. / Entérite nécrotique chez le poulet de gril. II. Caractères des souches de Clostridium perfringens isolées

A Gram positive bacillus, strictly anaerobic, was isolated from the viscera of all diseased birds showing lesions of necrotic enteritis. Its morphology and biochemical reactions, the presence of alpha and thêta hemolysins and the production of a lecithinase-C in vitro, all these characteristics indicated a similarity to those belonging to the group of Clostridium perfringens. The two hemolysins were neutralized in vitro only by the antitoxin A. Broiler chickens injected I.V. with a Viande-Foie (VF) broth culture of Clostridium perfringens together with the antitoxin A survived, whereas those receiving antitoxin C died. These results seem to indicate that this organism belongs to the type A. This bacillus was sensitive to a great variety of antibiotics, except neomycin.

[Necrotic enteritis in broilers. I. Clinoco-pathological aspect]. / Entérite nécrotique chez le poulet de gril. I. Aspect clinico-pathologique

This study represents an analysis of the principal clinical factors and pathological lesions of 150 cases of necrotic enteritis encountered during 1968 and 1969 in Quebec. Following multiple investigations no common factor was observed which might have explained the pathogenesis of the condition which was observed during every month of the year, especially from May to November. Birds two to four weeks of age were the most susceptible. The main lesion was a fibrino-necrotic enteritis always localized in the small intestine, either in its entire length or just a segment and characterized by the disappearance of the surface epithelium and necrosis of the villi. The lumen was filled with desquamated epithelial cells and bacteria. Foci of coagulation necrosis were observed in the liver and foci of nephrosis in the kidneys. A Gram+ bacillus, strictly anaerobic, was always isolated from the viscera.

Perception of changes in certain exteroceptive stimuli.

Although cybernetic models of one sort or another have become quite common in behavioral research, and although these models theoretically require a capacity for system detection of changes in error, no general psychophysical description of the individual human being's ability to discriminate different rates of stimulation is available. An initial survey of this type has been attempted and is reported here. For reasons which appear to be related to the biological mechanisms underlying sensory information processing, it is concluded, first, that ancillary cues of rate-related final magnitude are more valuable than cues of stimulus duration; second, that direct attention to on-going change is less precise than attention to final values only; and third, that differences in isochronal stimulus rates occurring in place or extent are more readily perceived than differences in isochronal rate of change in energy content, at least for the stimuli and ranges examined.