Probable lymphocytic hypophysitis diagnosed by short-term serial computed tomography and gallium-67 scintigraphy--case report.
(73/28924)
A 61-year-old female presented with headache, malaise, and left oculomotor nerve paralysis. Computed tomography (CT) demonstrated a diffuse pituitary mass and enlarged pituitary stalk with homogeneous contrast enhancement. Her symptoms gradually resolved without treatment. Gallium-67 scintigraphy showed abnormal uptake in the pituitary lesion. Serial CT every 2 weeks after admission showed homogeneous contrast enhancement and shrinking of the pituitary mass to a normal size 12 weeks after the onset. The final diagnosis was lymphocytic adenohypophysitis without biopsy. Recurrence has not been observed for 8 years after discharge. The patient did not need hormone replacement therapy. Histological examination is not always necessary to diagnose probable lymphocytic adenohypophysitis with the characteristic feature of rapid onset, abnormal gallium-67 uptake in the lesion, and resolution of symptoms in the acute stage with shrinking of the lesion on neuroimaging. (+info)
Airway closure, atelectasis and gas exchange during general anaesthesia.
(74/28924)
Airway closure and the formation of atelectasis have been proposed as important contributors to impairment of gas exchange during general anaesthesia. We have elucidated the relationships between each of these two mechanisms and gas exchange. We studied 35 adults with healthy lungs, undergoing elective surgery. Airway closure was measured using the foreign gas bolus technique, atelectasis was estimated by analysis of computed x-ray tomography, and ventilation-perfusion distribution (VA/Q) was assessed by the multiple inert gas elimination technique. The difference between closing volume and expiratory reserve volume (CV-ERV) increased from the awake to the anaesthetized state. Linear correlations were found between atelectasis and shunt (r = 0.68, P < 0.001), and between CV-ERV and the amount of perfusion to poorly ventilated lung units ("low Va/Q", r = 0.57, P = 0.001). Taken together, the amount of atelectasis and airway closure may explain 75% of the deterioration in PaO2. There was no significant correlation between CV-ERV and atelectasis. We conclude that in anaesthetized adults with healthy lungs, undergoing mechanical ventilation, both airway closure and atelectasis contributed to impairment of gas exchange. Atelectasis and airway closure do not seem to be closely related. (+info)
Spiral computed tomographic scanning and magnetic resonance angiography for the diagnosis of pulmonary embolism.
(75/28924)
PURPOSE: To compare prospectively the accuracy of spiral computed tomography (CT) with that of ventilation-perfusion scintigraphy for diagnosing pulmonary embolism. MATERIALS AND METHODS: Within 48 hours of presentation, 142 patients suspected of having pulmonary embolism underwent spiral CT, scintigraphy, and (when indicated) pulmonary angiography. Pulmonary angiography was attempted if interpretations of spiral CT scans and of scintigrams were discordant or indeterminate and intermediate-probability, respectively. RESULTS: In the 139 patients who completed the study, interpretations of spiral CT scans and of scintigrams were concordant in 103 patients (29 with embolism, 74 without). In 20 patients, intermediate-probability scintigrams were interpreted (six with embolism at angiography, 14 without); diagnosis with spiral CT was correct in 16. Interpretations of spiral CT scans and those of scintigrams were discordant in 12 cases; diagnosis with spiral CT was correct in 11 cases and that with scintigraphy was correct in one. Spiral CT and scintigraphic scans of four patients with embolism did not show embolism. Sensitivities, specificities, and kappa values with spiral CT and scintigraphy were 87%, 95%, and 0.85 and 65%, 94%, and 0.61, respectively. CONCLUSION: In cases of pulmonary embolism, sensitivity of spiral CT is greater than that of scintigraphy. Interobserver agreement is better with spiral CT. (+info)
Flitting radiographic shadows: an unusual presentation of cancer in the lungs.
(76/28924)
Tumour involvement of pulmonary blood vessels occurs frequently in advanced lung cancer and occasionally may cause pulmonary infarction. A case is reported of diffuse obstruction of pulmonary arteries by cancer in which no primary tumour was found, and which presented as flitting radiographic opacities due to pulmonary infarction. (+info)
Atherosclerosis of the ascending aorta is an independent predictor of long-term neurologic events and mortality.
(77/28924)
OBJECTIVES: This study was undertaken to determine whether atherosclerosis of the ascending aorta is a predictor of long-term neurologic events and mortality. BACKGROUND: Atherosclerosis of the thoracic aorta has been recently considered a significant predictor of neurologic events and peripheral embolism, but not of long-term mortality. METHODS: Long-term follow-up (a total of 5,859 person-years) was conducted of 1,957 consecutive patients > or =50 years old who underwent cardiac surgery. Atherosclerosis of the ascending aorta was assessed intraoperatively (epiaortic ultrasound) and patients were divided into four groups according to severity (normal, mild, moderate or severe). Carotid artery disease was evaluated (carotid ultrasound) in 1,467 (75%) patients. Cox proportional-hazards regression analysis was performed to assess the independent effect of predictors on neurologic events and mortality. RESULTS: A total of 491 events occurred in 472 patients (neurologic events 92, all-cause mortality 399). Independent predictors of long-term neurologic events were: hypertension (p = 0.009), ascending aorta atherosclerosis (p = 0.011) and diabetes mellitus (p = 0.015). The independent predictors of mortality were advanced age (p < 0.0001), left ventricular dysfunction (p < 0.0001), ascending aorta atherosclerosis (p < 0.0001), hypertension (p = 0.0001) and diabetes mellitus (p = 0.0002). There was >1.5-fold increase in the incidence of both neurologic events and mortality as the severity of atherosclerosis increased from normal-mild to moderate, and a greater than threefold increase in the incidence of both as the severity of atherosclerosis increased from normal-mild to severe. CONCLUSIONS: Atherosclerosis of the ascending aorta is an independent predictor of long-term neurologic events and mortality. These results provide additional evidence that in addition to being a direct cause of cerebral atheroembolism, an atherosclerotic ascending aorta may be a marker of generalized atherosclerosis and thus of increased morbidity and mortality. (+info)
The presence of infection-related antiphospholipid antibodies in infective endocarditis determines a major risk factor for embolic events.
(78/28924)
OBJECTIVES: The impact of infection-associated antiphospholipid antibodies (APA) on endothelial cell activation, blood coagulation and fibrinolysis was evaluated in patients with infective endocarditis with and without major embolic events. BACKGROUND: An embolic event is a common and severe complication of infective endocarditis. Despite the fact that APAs are known to be associated with infectious diseases, their pathogenic role in infective endocarditis has not been clearly defined. METHODS: The relationship among the occurrence of major embolic events, echocardiographic vegetation size, endothelial cell activation, thrombin generation, fibrinolysis and APA was examined in 91 patients with definite infective endocarditis, including 26 patients with embolic events and 65 control subjects without embolic events. RESULTS: Overall, 14.3% of patients exhibited elevated APA levels. Embolic events occurred more frequently in patients with elevated levels of APA than in patients without (61.5% vs. 23.1%; p = 0.008). Patients with elevated levels of APA showed higher levels of prothrombin-fragment F1 +2 (p = 0.005), plasminogen-activator inhibitor 1 (p = 0.0002), von Willebrand factor (p = 0.002) and lower levels of activated protein C (p = 0.001) than patients with normal levels of APA. Thrombin generation and endothelial cell activation were both positively correlated with levels of APA. The occurrence of elevated APA levels was frequently associated with structural valve abnormalities (p = 0.01) and vegetations >1.3 cm (p = 0.002). CONCLUSIONS: Infection-associated elevated APA levels in patients with infective endocarditis are related to endothelial cell activation, thrombin generation and impairment of fibrinolysis. This may contribute to the increased risk for major embolic events in these patients. (+info)
Tomographical description of tennis-loaded radius: reciprocal relation between bone size and volumetric BMD.
(79/28924)
Effects of long-term tennis loading on volumetric bone mineral density (vBMD) and geometric properties of playing-arm radius were examined. Paired forearms of 16 tennis players (10 women) and 12 healthy controls (7 women), aged 18-24 yr, were scanned at mid and distal site by using peripheral quantitative computerized tomography. Tomographic data at midradius showed that tennis playing led to a slight decrease in cortical vBMD (-0.8% vs. nonplaying arm, P < 0. 05) and increase both in periosteal and endocoritcal bone area (+15. 2% for periosteal bone, P < 0.001; and +18.8% for endocortical bone, P < 0.001). These data suggest that, together with an increase in cortical thickness (+6.4%, P < 0.01), cortical drift toward periosteal direction resulted in improvement of mechanical characteristics of the playing-arm midradius. Enlargement of periosteal bone area was also observed at distal radius (+6.8%, P < 0.01), and the relative side-to-side difference in periosteal bone area was inversely related to that in trabecular vBMD (r = -0.53, P < 0.05). We conclude that an improvement of mechanical properties of young adult bone in response to long-term exercise is related to geometric adaptation but less to changes in vBMD. (+info)
Accurate assessment of abdominal aortic aneurysm with intravascular ultrasound scanning: validation with computed tomographic angiography.
(80/28924)
PURPOSE: The purpose of this study was to assess the accuracy of intravascular ultrasound (IVUS) parameters of abdominal aortic aneurysm, used for endovascular grafting, in comparison with computed tomographic angiography (CTA). METHODS: This study was designed as a descriptive study. Between March 1997 and March 1998, 16 patients with abdominal aortic aneurysms were studied with angiography, IVUS (12.5 MHz), and CTA. The length of the aneurysm and the length and lumen diameter of the proximal and distal neck obtained with IVUS were compared with the data obtained with CTA. The measurements with IVUS were repeated by a second observer to assess the reproducibility. Tomographic IVUS images were reconstructed into a longitudinal format. RESULTS: IVUS results identified 31 of 32 renal arteries and four of five accessory renal arteries. A comparison of the length measurements of the aneurysm and the proximal and distal neck obtained with IVUS and CTA revealed a correlation of 0.99 (P <.001), with a coefficient of variation of 9%. IVUS results tended to underestimate the length as compared with the CTA results (0.48 +/- 0.52 cm; P <.001). A comparison of the lumen diameter measurements of the proximal and distal neck derived from IVUS and CTA showed a correlation of 0.93 (P <.001), with a coefficient of variation of 9%. IVUS results tended to underestimate aneurysm neck diameter as compared with CTA results (0.68 +/- 1.76 mm; P =.006). Interobserver agreement of IVUS length and diameter measurements showed a good correlation (r = 1.0; P <.001), with coefficients of variation of 3% and 2%, respectively, and no significant differences (0.0 +/- 0.16 cm and 0.06 +/- 0.36 mm, respectively). The longitudinal IVUS images displayed the important vascular structures and improved the spatial insight in aneurysmal anatomy. CONCLUSION: Intravascular ultrasound scanning results provided accurate and reproducible measurements of abdominal aortic aneurysm. The longitudinal reconstruction of IVUS images provided additional knowledge on the anatomy of the aneurysm and its proximal and distal neck. (+info)