Quantification of articular cartilage in the knee with three-dimensional MR imaging.

RATIONALE AND OBJECTIVES: To determine the volume of articular cartilage in cadavers, patients, and healthy volunteers by using a volumetric, fat-suppressed spoiled gradient-recalled signal acquisition in the steady state (SPGR) magnetic resonance (MR) sequence. METHODS: Sagittal MR images were obtained with a fat-suppressed SPGR sequence (repetition time, 52 msec; echo time, 10 msec; 60 degrees flip angle; 3.0-3.5-mm partitions, 256 x 192 matrix, two signals acquired). The cartilaginous surfaces of the tibia, femur, and patella were planimetrically defined with a three-dimensional workstation. A three-dimensional model volume was created by threshold segmenting the cartilage from the adjacent tissues. The volume as calculated by using MR imaging was compared with the actual volume of the cartilage specimens. RESULTS: Observed measurements correlated with actual weight and volume displacement measurements with an accuracy of 82%-99% and linear correlation coefficients of 0.99 (P = 2.5e-15) and 0.99 (P = 4.4e-15). Precision of segmentation in healthy volunteers yielded a coefficient of variation of 0.4% for interobserver variability and 0.3% for intraobserver variability. CONCLUSION: This pilot study suggests that accurate volumetric calculations of knee articular cartilage are possible with currently available MR imaging pulse sequences and a commercially available work station.

Computed tomography-guided needle localization of nonpalpable breast lesions: review of 24 cases.

RATIONALE AND OBJECTIVES: We examined the role of computed tomography (CT) in breast imaging, especially in guiding needle localization procedures. METHODS: We reviewed our institution's breast imaging database, from 1978 to 1994, for procedures in which CT scanning was used. Twenty-four CT-guided needle localizations were identified. Medical records, mammograms, CT scans, and pathology reports were reviewed for all patients. RESULTS: Twenty-four needle localizations were performed on 22 female patients. The average size of the lesions localized was 12 mm. The most common reason for CT scanning was the inability to image a suspicious density by conventional mammography on two orthogonal views. Nine malignant and 15 benign lesions were localized under CT guidance. One patient developed a postoperative hematoma. No other complications occurred. CONCLUSION: CT-guided breast localization is a reliable technique that may be used to define selected breast lesions that are difficult to triangulate or localize by conventional two-view mammography.

Radiographic aspects of pneumothorax.

Pneumothorax is a common medical problem of varied etiology. Because pneumothorax has potentially severe acute consequences, it is important that all physicians know its radiographic appearance. Patient complaints are nonspecific, and physical examination findings are often subtle. The chest radiograph is the principal means of detecting and following a pneumothorax. Radiographic diagnosis on an upright film requires the detection of the visceral pleural line. For radiographs obtained with the patient in the supine position, pneumothorax may be manifested by increased lucency over the upper quadrant of the abdomen, an unusually sharp definition of the anterior diaphragmatic surface or a very wide and deep costophrenic angle.

High-resolution CT of the lungs.

High-resolution computed tomography (CT) of the lung provides detailed visualization of the lung parenchyma. The technique involves the use of thin-section axial tomography. High-resolution CT can facilitate the diagnosis of certain pulmonary processes. It is useful in differentiating similar patterns of abnormalities seen on chest radiographs, such as those seen in lymphangitic carcinomatosis and sarcoidosis, and in delineating the extent of co-morbid lung diseases, such as emphysema and asbestosis. In some chronic processes such as idiopathic pulmonary fibrosis, high-resolution CT can be used for biopsy of areas of active inflammation, thus increasing the diagnostic yield. As clinicians and radiologists become more familiar with high-resolution CT, it is likely that its role in the diagnosis and assessment of lung disease will increase.

Occupational health, stress, and work organization in Australia.

Contemporary issues and changes in occupational health are reviewed in this article, with particular reference to salient historical and ideological influences on industrial relations in Australia. Comprehensive occupational health and safety legislation has been introduced recently, and the views of employers and unions are analyzed. Research into occupational stress has continued to provide guidelines for work reform, but the controversy generated by the Australian phenomenon known as Repetition Strain Injury (RSI) has raised important issues for the work reform movement.

The physiological measurement of acute stress (public speaking) in bank employees.

An evaluation of a number of non-invasive physiological measures of stress was conducted, using bank employees attending a two-week residential course. The stressor involved was the preparation and delivery of a 15-min public lecture. The physiological parameters measured were urinary excretion rates of noradrenaline (NA), adrenaline (A), dopamine and cortisol, the ratio of NA/A, salivary cortisol levels, heart rate and blood pressure. Measurements were taken at 08.30, 10.30, 12.30, 15.30 and 17.30 h on the day of the public lecture and on the following (control) day. The public lectures were given between 10.30 and 12.30 h. The urinary excretion rates of adrenaline and cortisol were significantly elevated immediately following, but not before, the public lectures. The ratio NA/A was significantly decreased and the salivary cortisol levels were significantly increased both immediately before and after the public lecture. Urinary excretion rates of noradrenaline and dopamine, blood pressure and heart rate were unchanged by the stressor. Measurement of salivary cortisol levels, as well as providing a simple, stress free, non-invasive collection procedure, more closely reflects in time the changes in plasma levels of the hormone, not suffering from the large lag-time involved with urinary hormone measurements. Salivary cortisol measurement would appear to be the measurement of choice in human stress studies where individual stress factors are to be identified and studied. The significance of the stress-induced elevation in cortisol and catecholamine levels in the link between illness and occupational stress is discussed.

Rhetoric as remedy: some philosophical antecedents of psychotherapeutic ethics.

Earliest forms of psychotherapy were based on noble rhetoric and a model of the human encounter regulated by values of virtue and courage (responsible autonomy). In this paper the relationship between noble and base rhetoric and values is considered and applied to the psychotherapeutic setting. Bühler's and Popper's hierarchy of language and values is extended so that the language of expression, communication, description, advice, argument, and promises may be related to noble and base values which, it is argued, therapists and clients invoke to define and condition the therapeutic relationship. An ethical hierarchy of language and values, based on the principle of responsible autonomy, is suggested for psychotherapeutic practice.

Urinary cortisol excretion and mood ratings in aircraft cabin crew during a tour of duty involving a disruption in circadian rhythm.

A psychophysiological study was carried out on 28 cabin crew, comprising two teams, who were to travel from Sydney to Los Angeles and return, with stopovers in Los Angeles of 58 and 82 hr respectively. Every urine sample for a period of nine days, commencing 2 days before the flight, was collected. The volume and time the sample was passed were recorded so that urinary cortisol secretion rates could be calculated. Mood was also rated on a scale scored 0-9 at the same time the urine sample was collected. A control group matched for age, sex ratio, and degree of manual labour involved in their occupation, but not involved with the flights, was included in the study for comparison. On the basis of urinary cortisol excretion rates, the crews in Sydney before the flight and in Los Angeles were more highly stressed than the control group. The urinary cortisol excretion rates were significantly greater than those of the control group in Sydney before the flight, in Los Angeles, and during the return flight, but not on the flight out. The high excretion rates before the flight were attributed to an apprehension factor, whereas the elevated values in Los Angeles and during the flight back were attributed to a disruption in circadian rhythm. A factor analysis of mood ratings showed three major factors assessing vitality, distress, and relaxation. Analysis of variance of the mood ratings showed significant changes over the tour of duty for 13 of the 14 moods.

Stress at work: a review of Australian research.

This paper reviews Australian research into occupational stress. The context of organizational life in Australia is outlined, including the attitudes and values that have conditioned stress research. Empirical studies of occupational stress and health are reviewed, and new psychobiological studies which index stress by urinary hormonal analysis (catecholamines, cortisol) are detailed. The use of stress management programs at the workplace is discussed within the context of Australian industrial relations and workers' compensation developments.