Restricted field of view magnetic resonance imaging of a dynamic time series.

A restricted field of view (rFOV) approach for imaging a dynamic time series of volumes of limited spatial extent within a larger subject is described. The shorter readout with rFOV-MRI can be exploited to either limit image artifacts or increase spatial resolution. To accomplish rFOV imaging of a multislice volume for a dynamic series, an outer volume suppression (OVS) preparation that saturates signal external to a cylinder through the subject is followed by slice-selective excitation and a spiral readout. The pass- and stopband efficiencies of the OVS in an agar gel phantom were 97% (+/-1.5%) and 3% (+/-1%), respectively. Profiles of the temporal signal-to-noise ratio (SNR) were measured in a phantom and an adult brain. The rFOV sequence reduced distortions from off-resonance signal and T2*-induced blurring compared to a conventional sequence. Sequence utility is demonstrated for high-resolution rFOV functional MRI (fMRI) in the visual cortex. The rFOV sequence may prove to be useful for other multislice dynamic and high-resolution imaging applications.     

Patients' Expectations of Asthma Treatment

A multicomponent model has been developed to explain patients' unmet expectations of medical care. The model proposes that expectations are related to patients' personal experiences with illness, perceived vulnerability to disease, transmitted knowledge, and perceived severity of disease. The objective of this cross-sectional study was to determine whether this model can be applied to patients' unrealistic expectations of treatment outcomes, specifically expecting to be cured of asthma. In total, 230 patients observed in a primary care practice in New York City were interviewed in person with open-ended questions about their expectations of asthma treatment. Responses were analyzed with qualitative techniques to generate categories of expectations. Patients had a mean age of 41 ± 11 years, 21% were white, 30% African American, 42% Latino, and 7% other groups. Major categories of expectations were generated from patients' responses and included symptom relief (expected by 52%), cure (36%), improved physical function (21%), and improved psychological well-being (15%). The category of expecting a cure was assessed with patients' responses to the following items representing components of the model: 1) resource utilization and medication requirements for asthma (representing severity of disease); 2) perceived quality of asthma care and satisfaction with care (representing past asthma experiences); 3) the Asthma Self-Efficacy Scale (representing perceived vulnerability to exacerbations); and 4) experiences of social network contacts with asthma and the Check Your Asthma IQ survey (representing transmitted knowledge). In bivariate analysis, patients who expected a cure were more likely to be Latino or Native American or Asian (p = 0.02), to have never required oral corticosteroids (p = 0.004), to be dissatisfied with the status of their asthma (p = 0.008), to know others who were limited by asthma (p = 0.03), to have worse Asthma Self-Efficacy Scale scores (p = 0.002), to have worse Check Your Asthma IQ scores (p = 0.04), and to currently be taking inhaled corticosteroids (p = 0.03). In multivariate analysis, worse asthma self-efficacy (p = 0.008), never having required oral corticosteroids (p = 0.005), and currently taking inhaled corticosteroids (p = 0.05) remained associated with expecting a cure. As a result of this study, we found that patients have multiple expectations of asthma treatment, including realistic expectations such as symptom relief and improved function, as well as unrealistic expectations, specifically to be cured of asthma. A multicomponent model of patient and disease characteristics was associated with this unrealistic expectation. These findings indicate that clinicians can intervene in diverse areas to foster realistic expectations of treatment outcomes among asthma patients.     

Assessing impairment in patients with panic disorder: the Sheehan Disability Scale

Summary The DSM-III-R incorporates both distress (symptoms) and disability (impairment) in the definition of a psychiatric disorder. In psychiatric research there is a wide array of instruments used to measure symptom severity, but a limited selection for the assessment of impairment. The psychometric properties of one such instrument, The Sheehan Disability Scale (Sheehan 1983), are evaluated in this paper. The data analyzed come from two studies of patients with panic disorder, the Cross National Collaborative Panic Study-Phase I and the Panic Depression Study. In this report both the alpha coefficients and factor analyses indicate that the reliability of the scale is acceptable. The factor structure of the items and the sensitivity to change of their composite demonstrate satisfactory construct validity. The criterion-related validity is substantiated by the significant relationship between symptomatology and impairment. These analyses were limited to patients with panic disorder. Further work is needed to evaluate the instrument in assessing patients with other disorders.