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11.
Central thrombi in pulmonary arterial hypertension detected by MR imaging   总被引:1,自引:0,他引:1  
Fisher  MR; Higgins  CB 《Radiology》1986,158(1):223-226
Differentiation of thrombi from slow flow in the pulmonary arteries, sometimes observed in the presence of pulmonary arterial hypertension, can be equivocal. Magnetic resonance (MR) imaging was performed in a patient with chronic pulmonary thromboembolism and pulmonary arterial hypertension using an electrocardiographically gated technique that allowed visualization of the pulmonary arteries at the end of diastole and multiple times during systole. These images were compared with those of a patient with primary pulmonary hypertension and those of healthy subjects. Thrombi were discrete structures, seen throughout the cardiac cycle on both the first and second spin-echo images, and decreased in signal intensity on the second image. Slow flow increased in signal intensity and changed in structure during the cardiac cycle and was seen best on the second image. MR may play an important role in excluding large central thrombi as the cause of pulmonary arterial hypertension. It is a noninvasive method for defining pulmonary arterial wall thickness and for direct visualization of chronic pulmonary thrombus.  相似文献   
12.
13.
Colorectal hemangioma: radiologic findings   总被引:1,自引:0,他引:1  
The authors correlated radiographs with the clinical and histologic data of 12 patients with colorectal hemangioma. All patients presented with rectal bleeding, which was chronic in seven. Phleboliths were also visible in seven cases, which correlated with chronic bleeding in five. On barium studies, three masses were soft and three produced rigid narrowing. The atypical features of rigid luminal narrowing, which might mimic a carcinoma, and hypovascularity correlated with chronic bleeding or visible phleboliths, which suggest the correct diagnosis of colorectal hemangioma.  相似文献   
14.
Background: To describe the long‐term outcomes of trabeculectomies performed at Dunedin Hospital and followed in the Otago Glaucoma Surgery Outcome Study. Methods: Prospective non‐comparative case series of 841 eyes of 607 patients who had first trabeculectomies for primary open‐ or closed‐angle glaucoma at Dunedin Hospital between 1976 and 2005 and followed for a mean of 7.5 years (standard deviation 6.0). Results: The probability of a trabeculectomy controlling the intraocular pressure at 21 mmHg or less at 1, 10 and 20 years was 0.96 (95% confidence interval [CI] 0.95, 0.97), 0.86 (95% CI 0.83, 0.89) and 0.79 (95% CI 0.74, 0.83), respectively. Visual acuity was maintained or improved between preoperative assessment and final follow up in 68% of cases. The probability of not being blind following trabeculectomy at 1, 10 and 20 years was 0.98 (95% CI 0.96, 0.98), 0.83 (95% CI 0.80, 0.87) and 0.70 (95% CI 0.64, 0.76), respectively. The proportion of those with glaucomatous field loss increased during follow up from 16% (44/283) at 0–5 years to 50% (10/20) for those with 21 or more years of follow up. A repeat drainage procedure was required in 65 eyes (8%) (56 Molteno implant insertions and 9 repeat trabeculectomies). Conclusions: Intraocular pressure was well controlled by trabeculectomy; however, a steady decline in intraocular pressure control, visual acuity and visual field occurred during follow up.  相似文献   
15.
OBJECTIVE: The aim of this study was to examine quality of care for hospitalized Medicare beneficiaries with peptic ulcer disease. METHODS: Collaborating with five Peer Review Organizations, we used 1995 Medicare claim files to select samples of inpatients with a principal diagnosis of peptic ulcer disease. Quality of care indicators developed by content experts included percentages for ulcer patients tested for Helicobacter pylori (H. pylori); biopsied patients who received tissue tests; H. pylori-positive patients who received appropriate therapy; and ulcer patients screened for preadmission nonsteroidal anti-inflammatory drug (NSAID) use and counseled about risks. RESULTS: Of 2,644 patients eligible for medical record review, 56% were tested for H. pylori, and 73% of those testing positive were treated appropriately; 84% of patients with endoscopic biopsies received a tissue test for H. pylori; 74% of patients were screened for preadmission NSAID use, 24% had documented counseling of NSAID use, and only 2% had documented counseling on the ulcer risk of NSAID use. Statistically significant regional variation occurred in four of six quality indicators. Outpatient records were reviewed for 529 patients to document prior outpatient H. pylori in this population; only 2% (n = 12) were tested for H. pylori in the year before admission. CONCLUSIONS: Opportunities exist to improve quality of care by testing for and treating H. pylori in hospitalized Medicare beneficiaries with peptic ulcer disease and to improve screening for NSAIDs and counseling on ulcer risks.  相似文献   
16.
Five of the six families with the Berardinelli Seip syndrome in Norway cluster in six adjacent rural municipalities of south-western Norway. The six patients from this area were born between 1951 and 1973, none between 1974 and 1995. The absence of new cases may be explained by a decrease in the intraregion marriage rate and inbreeding. Genealogical investigations show that the mutation must have occurred at least 400 years ago. The sixth family was clinically different and geographically sporadic from a Finnish-descent rural East Norwegian population. A genetic linkage study of all six families revealed fresh crossovers versus the disease allele in nine DNA marker systems and the absence of recombination in three (maximum lod score + 1.3). None of the last showed allelic association. These families are included in an international effort to map the CLBS locus. The patients have been included in the homozygosity testing of totally 28 patients in an international collaborative study. The three patients, assumed identical in descent from both parents, were jointly homozygous in none of the 250 dinucleotide markers tested. A heterochromatic 9qh + segregated from one parent in two families.  相似文献   
17.
Childhood tuberculosis is perceived by many as a disease of the past. Experience in a children's hospital serving a deprived population suggested that tuberculosis and other mycobacterial infections were not declining in clinical practice. Fifty three tuberculous and 11 atypical mycobacterial infections were identified between 1978 and 1992. There was no decline in tuberculosis and nine of the 11 atypical infections occurred in the last five years. Altogether 40% of cases of tuberculosis were in non-Asian children; 32% had arrived in the UK or visited family overseas in the previous year; and 38% had a history of tuberculosis contact, usually a close adult relative. Nationally, the previous decline in tuberculosis in all ages has reversed. In the local health districts in London's east end, childhood tuberculosis has also stopped declining and seems to be increasing. It is regrettable that BCG vaccination has been abolished by some districts in the UK, against current recommendations. Childhood tuberculosis is still common in the practice described here, including among children who do not fall into conventionally recognised high risk groups. Inner city dwellers and junior doctors are both highly mobile populations, adding to the risk that paediatricians, particularly those in training, may encounter tuberculosis with little or no previous experience of the condition.  相似文献   
18.
BACKGROUND: A multidisciplinary panel representing various stakeholders in the health care delivery and oncology services marketplace was convened to develop specific criteria for healthcare purchasers to consider when evaluating the structures and processes of health plans. These rank ordered criteria also can be used by oncologic service providers and health plan designers as a yardstick for the services they offer. METHODS: A multidisciplinary 31-member Task Force was assembled by the Kerr L. White Institute and the American Cancer Society in March 1997. Task Force members were selected for their ability to offer expert insight as purchasers, suppliers, policymakers, consumers, or stakeholders in the health care marketplace. A preference-weighted majority voting rule was used to identify the three most important recommendations of the 10 that were generated through a modified Delphi technique. To test the practicality of the top three recommendations, leaders of large managed care organizations (MCOs) were surveyed; the results of this survey then were compared with the results of the Task Force survey. RESULTS: The three most important recommendations from the Task Force were that health plans provide access to: 1) comprehensive cancer care, 2) preventive and screening services, and 3) second opinions and treatment options supported by scientific evidence. The difference between the responses of the Task Force and the MCOs was that MCOs placed the highest importance on evidence-based decision-making, with their next three rankings coinciding with those identified by the Task Force. CONCLUSIONS: The value of these summary recommendations will be realized through their use by both purchasers and suppliers to influence the structure and content of the delivery of oncologic services.  相似文献   
19.
Cardiac imaging with a high-speed Cine-CT Scanner: preliminary results   总被引:2,自引:0,他引:2  
Lipton  MJ; Higgins  CB; Farmer  D; Boyd  DP 《Radiology》1984,152(3):579
  相似文献   
20.
Both ultrasonography (US) and cholescintigraphy are used to study gallbladder dynamics. The present study was undertaken to determine whether the two methods provide the same or different information relating to gallbladder emptying. Emptying was simultaneously studied with both methods during infusion of graded physiologic doses of cholecystokinin (CCK) in six healthy subjects. Infusion of stepwise increasing doses of CCK, ranging from 0.03 to 0.5 Ivy dog units per kilogram of body weight per hour (IDU/kg.h), induced significant dose-related increases in plasma CCK, decreases in gallbladder volume assessed with US, and gallbladder emptying assessed with cholescintigraphy. The threshold dose for inducing significant gallbladder emptying was 0.13 IDU/kg.h, as determined with both techniques, indicating similar detection limits. There was a highly significant correlation between decreases in gallbladder volume and decreases in radioactive counts over the gallbladder region, with a tendency toward greater gallbladder responses at sonography during the early phase of gallbladder contraction and toward greater responses at cholescintigraphy during the later phase of gallbladder contraction. It is concluded that these methods can be used interchangeably for the quantitation of gallbladder emptying.  相似文献   
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