CT of the brain: a comparison of transportable and fixed-platform scanners.

OBJECTIVE: The purpose of this study was to determine whether an in-hospital transportable CT scanner can provide diagnostic brain images and to compare the quality of these images with those from a conventional fixed-platform CT scanner. SUBJECTS AND METHODS: Twenty-seven patients with known or suspected intracranial pathology underwent imaging on a transportable scanner and a fixed-platform scanner within 1 hr of each other. Images from each CT examination were evaluated independently by two neuroradiologists who were unaware of patient history. Conspicuousness of intracranial pathology and normal anatomy were rated on a 5-point scale (1 point, optimal; 5 points, poor or not visualized). Statistical comparisons were made using nonparametric tests. RESULTS: Seven CT scans were interpreted as showing normal findings and 20 scans revealed intracranial pathology on both CT scanners. Image quality was higher on the fixed scanner (average rating, 2.42 points; SE = .12) than on the transportable scanner (average rating, 3.10 points; SE = .12) (p = .001). Depiction of the cerebellum, midbrain, and supratentorial gray-white matter was better on the fixed scanner (p < .05). However, we found no significant differences in detection of intracranial pathology between scanners. Both radiologists found images from both scanners to be diagnostic in all 27 patients. CONCLUSION: Images of the brain on the transportable CT scanner were less clear than those on a fixed scanner. However, images from the transportable CT scanner were diagnostic in 27 consecutive patients. The implications of this finding are important for the provision of CT services for critically ill patients who cannot be transported to the radiology department.

Monte carlo simulation of a single-molecule detection experiment.

The physical and instrumental processes that occur in experiments for the detection of individual fluorescent molecules in solution are described, with emphasis on their incorporation into a quantitative Monte Carlo simulation. The simulation is applied to the conditions of a past experiment [Appl. Opt. 34, 3208 (1995)], which utilizes a sheath flow system for high detection efficiency, and it generates comparable results, while helping to identify experimental limitations. The simulation indicates that the use of low dead-time electronics and appropriate selection of experimental parameters should enable detection at more rapid rates for applications in which large numbers of molecules are to be efficiently counted.

Effects of Medicare's prospective payment system on service use by depressed elderly inpatients.

OBJECTIVE: To determine the effects of Medicare's prospective payment system (PPS) on hospital care, changes in length of stay and intensity of clinical services received by 2,746 depressed elderly patients in 297 acute care general medical hospitals were studied. METHODS: A pre-post design was used, and differences in sickness at admission were controlled for. Data on length of stay and use of specific clinical services were obtained from the medical record using a medical record abstraction form. Care provided on units exempt from PPS was compared with care provided in nonexempt units. RESULTS: After implementation of PPS, the average length of stay fell by up to three days within the different types of acute care settings studied, but this decline was partially offset by proportionately more admissions to psychiatric units, which had longer lengths of stay. Intensity of clinical services increased after PPS implementation, especially in nonexempt psychiatric units. CONCLUSION: Despite financial incentives for hospitals to reduce clinical services under PPS, its implementation was not associated with a marked decline in length of stay, when averaged across all treatment settings, and was associated with an increase in the intensity of many clinical services used by depressed elderly patients in general hospitals.

Quality of care for depressed elderly patients hospitalized in the specialty psychiatric units or general medical wards.

BACKGROUND: Studies to assess quality of care have become increasingly important for research and policy purposes. OBJECTIVE: To evaluate the difference in quality of care between elderly depressed patients hospitalized in specialty psychiatric units and those hospitalized in general medical wards. METHODS: We reviewed retrospectively the medical charts of 2746 patients with depression hospitalized in 297 general medical hospitals in five different states. Quality of care was assessed by clinical review of explicit and implicit information contained in the medical records of patients in specialty psychiatric units (n = 1295) and general medical wards (n = 1451). We also used other secondary data sources to determine postdischarge outcomes. RESULTS: We found that (1) a higher percentage of admissions on the psychiatric units were considered appropriate, (2) overall psychological assessment was better on the psychiatric unit, (3) patients were more likely to receive psychological services on the psychiatric wards but more likely to receive traditional general medical services on medical wards, (4) there were more inpatient general medical complications on the psychiatric wards, and (5) implicit measures of clinical status at discharge were better for those on the psychiatric unit. CONCLUSIONS: Although limited by reliance on medical record abstraction and a retrospective study design, our data indicate that the quality of care for the psychological aspects of the treatment of depression may be better on psychiatric units, while the quality of general medical components of care may be better on general medical wards.

Quality of care for depressed elderly pre-post prospective payment system: differences in response across treatment settings.

We evaluated the quality of care for depressed elderly patients (n = 2,746) hospitalized in general medical hospitals (n = 297) before or after implementation of Medicare's Prospective Payment System, focusing on whether the response to time period differed for hospitals that in the post-PPS period had no psychiatric unit, an exempt psychiatric unit, or a nonexempt unit, and by ward placement within hospitals with psychiatric units. Quality of care increased over time, and for most measures of quality of care the level of improvement did not differ significantly across different types of hospitals or by ward placement. The intensity of use of therapeutic services, such as rehabilitation, occupation, or recreation therapy, increased over time, particularly in nonexempt psychiatric units and hospitals without psychiatric units, such that these locations caught up some over time in the level of use of these services to the level for exempt psychiatric units. Several outcomes of care improved over time, and the degree of improvement in the rate of inpatient medical and psychiatric complications and other outcomes was significantly greater for psychiatric units that were exempt post-PPS than for nonexempt treatment locations.

Quality of care for hospitalized depressed elderly patients before and after implementation of the Medicare Prospective Payment System.

OBJECTIVE: The authors evaluated the impact of Medicare's Prospective Payment System on aspects of quality of care and outcomes for depressed elderly inpatients in acute-care general medical hospitals. METHOD: The depressed elderly inpatients (N = 2,746) were hospitalized in 297 acute-care general medical hospitals. The authors used a retrospective before-and-after design, controlling for differences over time in sickness at admission. Quality of care and outcomes were assessed through clinical review of explicit and implicit information in the medical records; secondary data sources provided information on postdischarge outcomes. RESULTS: After implementation of the prospective payment system 1) a higher percentage of patients had clinically appropriate acute-care admissions; 2) the initial assessment of psychological status by the treating provider was more complete; 3) the quality of psychotropic medication management, as rated by the study psychiatrists, improved; 4) the rates of any inpatient medical or psychiatric complication, of discharge to another hospital or a nursing home, and of inpatient readmission declined; and 5) there was no marked change in the percentage of patients rated by study clinicians as having acceptable overall clinical status at discharge or the rate of mortality 1 year after admission. CONCLUSIONS: After the implementation of the Medicare Prospective Payment System, the quality of care for depressed elderly inpatients improved and there was no marked increase in adverse clinical outcomes. Despite these gains, after implementation the quality of care was moderate at best and over one-third of the patients had unacceptable clinical status at discharge.