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The purpose of this study is to identify the local availability and trends in local availability of imaging technology and interpretation services in rural hospitals in the northwestern United States during the period between 1991 to 1994. Another objective is to describe hospital and community factors associated with the diffusion of image production and interpretation services. The information for this study was gathered through telephone surveys of rural hospital administrators in eight northwestern states in 1991 and 1994. The availability of magnetic resonance imaging (MRI) equipment, computed tomography (CT) scanners, ultrasonography equipment, and dedicated mammography equipment increased between 1991 and 1994. The increases in MRI units were primarily in mobile equipment, while ultrasonography and mammography equipment increases were primarily fixed hospital-based units. In 1994, image interpretation in the rural hospitals was provided by both primary care and radiology physicians. Forty-six (11.5%) of the rural hospitals had no on-site radiology services and only 73 (18%) had daily radiology services. Between 1991 and 1994, 12 hospitals gained at least once-a-week radiology services, but 24 lost all radiology services. Teleradiology availability more than doubled during the three years. Radiology technology has diffused widely into rural communities in this region of the United States at differing rates for large and small hospitals. Radiologists are available to these hospitals only 46 percent of the days each year, with more days of availability in the larger hospitals and fewer days in the smaller hospitals. Teleradiology capability is increasing more rapidly in the larger hospitals that have radiologists more readily available. 相似文献
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Y Leskinen JP Salenius T Lehtim?ki H Huhtala H Saha 《American journal of kidney diseases》2002,40(3):472-479
BACKGROUND: Knowledge of the prevalence of peripheral arterial disease (PAD) in patients with chronic renal failure (CRF) is limited because of a lack of uniformity in disease definition and recognition. Furthermore, little is known of the prevalence of medial arterial calcification (MAC) in patients with CRF. Our goal is to study the prevalence of PAD and MAC defined by ankle brachial index (ABI) or toe brachial index (TBI) measurements in a Finnish population of patients with CRF consisting of predialysis and dialysis patients, as well as renal transplant recipients. METHODS: We examined 136 patients with CRF and 59 control subjects. Fifty-nine of the patients with CRF had moderate to severe predialysis CRF, 36 patients were on dialysis treatment, and 41 were renal transplant recipients. Mean age of patients was 51.9 +/- 11.5 years, and 39 patients (29%) had diabetes. ABI and TBI were measured by means of photoplethysmography. The definition of PAD required an ABI value of 0.90 or less, a TBI value of 0.60 or less, or a previous positive lower-extremity angiogram result. ABI values of 1.3 or greater or incompressible arteries at ankle level indicated MAC. The presence of claudication was determined by an interview. RESULTS: Prevalences of PAD on this study were 22.0% in patients with predialysis CRF, 30.6% in patients on dialysis treatment, 14.6% in renal transplant recipients, and 1.7% in the control group (P = 0.001). Prevalences of MAC were 23.7%, 41.7%, 23.1%, and 3.4% (P < 0.001), respectively. Only 9 patients had claudication, and 6 of those patients had PAD. CONCLUSION: Both asymptomatic PAD and MAC are common in patients with CRF. Therefore, we recommend the use of both ABI and TBI measurements in the evaluation of PAD in patients with CRF. 相似文献
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We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder. 相似文献
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