ABSTRACT
The purpose of this study was to visualize both the vessel wall and atherosclerotic plaques in virtual intra-arterial angioscopy (VIA) based on helical CT data sets. To achieve this in vitro, the optimal reconstruction threshold of the vessel wall was determined to be 56.4% of the maximum enhancement. Using this threshold, 20 patients suffering from symptomatic carotid disease were examined in a helical CT scanner. The degree of stenosis was defined using the North American Symptomatic Endarterectomy Trial (NASCET) criteria and compared with results from digital substraction angiography (DSA). Grading of stenoses was only possible by adding the separately computed plaque geometry to the geometry of the vessel wall in a second step. Correlation between VIA and DSA in low grade, medium grade and high grade stenosis was 88%, 93% and 71%, respectively. Complete occlusions were diagnosed correctly in all patients. Sensitivity and specificity for the correct diagnosis of high grade stenosis was 93.7% and 91.3%, respectively. A realistic depiction of intraluminal structures in carotid arteries can only be generated by displaying both the vessel wall and plaque structures simultaneously.
Subject(s)
Carotid Arteries/diagnostic imaging , Tomography, Spiral Computed/methods , Aged , Angioscopy/methods , Computer Simulation , Data Collection , Female , Humans , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Male , Middle Aged , Phantoms, ImagingABSTRACT
In 87 patients with histologically proven bronchogenic carcinoma, computerised tomography (CT) and bronchoscopy were performed to assess the accuracy of CT in detecting bronchial stenosis. Whereas patent airways and mainstem stenosis were recognised in 85% of the cases, the overall accuracy was only 57%. Furthermore, the results of both methods were compared to scintigraphy (ventilation, perfusion) to evaluate the functional impairment due to altered lung morphology and bronchial stenosis. With an increasing number of CT-diagnosed atelectatic or infiltrated segments an almost linear decrease in ventilation and perfusion values was observed. In comparison, bronchoscopy-diagnosed tumour stenosis resulted in decreased ventilation and perfusion data only if the lesion was centrally located.
Subject(s)
Bronchoscopy , Carcinoma, Bronchogenic/diagnosis , Lung Neoplasms/diagnosis , Tomography, X-Ray Computed , Adenocarcinoma/diagnosis , Adenocarcinoma/diagnostic imaging , Adult , Aged , Carcinoma, Bronchogenic/diagnostic imaging , Carcinoma, Small Cell/diagnosis , Carcinoma, Small Cell/diagnostic imaging , Carcinoma, Squamous Cell/diagnosis , Carcinoma, Squamous Cell/diagnostic imaging , Female , Fiber Optic Technology , Humans , Lung Neoplasms/diagnostic imaging , Male , Middle Aged , Radionuclide Imaging , Technetium Tc 99m Aggregated Albumin , Ventilation-Perfusion Ratio , Xenon RadioisotopesABSTRACT
Arteriosclerosis is a constant problem in long-term hemodialysis patients. Computer tomography of the abdominal aorta allows a well-defined and reproducible evaluation of aortosclerosis. In the cross-sectional study, aortosclerosis was significantly accelerated in 84 chronic hemodialysis patients and was comparable to the results found in 20-year older control patients without renal disease. The increase of aortosclerosis correlated significantly with age of the patient, smoking, and duration of dialysis therapy. Furthermore, increased VLDL cholesterol and decreased HDL cholesterol seem to enhance aortosclerosis in our dialysis patients. In the longitudinal study (two CT scans with a time interval of 87 +/- 62.7 months) in 36 dialysis patients, progressed aortosclerosis correlated significantly with the long duration of hypertriglyceridemia, VLDL cholesterol, uric acid, and calcium phosphate products. Progression of aortosclerosis was reduced in parathyroidectomized patients. The study suggests that premature aortosclerosis is found in dialysis patients. In addition to the common risk factor of aortosclerosis disturbed calcium phosphate and parathyroid hormone metabolism seem to enhance aortosclerosis in patients under maintenance hemodialysis.
Subject(s)
Aorta, Abdominal/parasitology , Arteriosclerosis/etiology , Renal Dialysis/adverse effects , Adult , Aged , Apolipoproteins A/blood , Apolipoproteins B/blood , Arteriosclerosis/physiopathology , Calcium Phosphates/metabolism , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Cholesterol, VLDL/blood , Cross-Sectional Studies , Female , Humans , Life Style , Longitudinal Studies , Male , Middle Aged , Parathyroid Hormone/metabolism , Parathyroidectomy , Tomography, X-Ray Computed , Triglycerides/bloodSubject(s)
Aortic Aneurysm, Abdominal/surgery , Blood Vessel Prosthesis Implantation , Computer Simulation , Finite Element Analysis , Hemodynamics/physiology , Imaging, Three-Dimensional , Stents , Tomography, X-Ray Computed , User-Computer Interface , Aortic Aneurysm, Abdominal/diagnosis , Aortic Aneurysm, Abdominal/physiopathology , Aortic Rupture/diagnosis , Aortic Rupture/physiopathology , Aortic Rupture/surgery , Computer Graphics , Female , Humans , Image Processing, Computer-Assisted , Male , PrognosisABSTRACT
Case reports of two patients with an unusual cause for a rapid increase in transaminases following liver transplantation are described. In the postoperative course, angiography revealed an arterial hypoperfusion of the liver due to a steal phenomenon with blood shunting from the hepatic to the splenic artery. In one case, the underlying pathophysiology was a pre-existing filiform stenosis of the celiac trunk with insufficient recruitment of arterial blood from the superior mesenteric artery via the pancreatic arcade. Adequate liver perfusion was restored by simple ligation of the common hepatic artery. In the other case, angiography showed an arteriovenous fistula formation of the splenic vessels and minimal blood flow through the hepatic vessels. This was successfully corrected by angiographic embolization of the splenic artery with metal coils. After therapeutic intervention, both patients rapidly recovered with excellent liver function.
Subject(s)
Arterial Occlusive Diseases/etiology , Hepatic Artery , Ischemia/etiology , Liver Transplantation/adverse effects , Liver/blood supply , Adult , Arterial Occlusive Diseases/complications , Celiac Artery , Humans , Liver Circulation , MaleABSTRACT
The aim of this study was to compare the outcome of consecutive patients with abdominal aortic aneurysms treated by open operation and endoluminal procedure. Between October 1996 and April 1998 consecutive patients with abdominal aortic aneurysms underwent surgical repair. Of these, 50 patients had conventional open repair, and 48 patients were treated endoluminally. Follow-up was made by clinical examination in the operation group; the stent group was controlled by spiral CT and angiography 1, 3, 6, and 12 months after operation. No significant difference was found in the perioperative mortality rate between the open repair group and the stent group. This study suggests that the endovascular procedure is safe and results in a shorter length of hospital stay and a shorter length of intensive care unit stay. As there are no long-term results, the endoluminal method requires a careful follow-up.
Subject(s)
Angioplasty, Balloon/instrumentation , Aortic Aneurysm, Abdominal/surgery , Blood Vessel Prosthesis Implantation , Stents , Aortic Aneurysm, Abdominal/diagnostic imaging , Aortography , Follow-Up Studies , Humans , Postoperative Complications/diagnostic imaging , Prosthesis Design , Tomography, X-Ray Computed , Treatment OutcomeABSTRACT
PURPOSE: We reviewed the literature of the last 40 years and report our experience with treating high flow priapism with fistula embolization in prepubertal boys. MATERIALS AND METHODS: Two boys had blunt perineal trauma and 1 had penile trauma (ages 6, 6 and 10 years). Painless priapism developed within 24 hours and lasted for 4 to 7 days before the patients presented to the hospital. Primary diagnosis was made on color Doppler ultrasound. When high flow priapism was diagnosed angiography of the internal iliac artery and embolization of the arteriocavernosal fistula were performed. Mean followup was 26 months. RESULTS: Color Doppler ultrasound revealed bilateral arteriocavernosal fistulas in 2 boys and a unilateral fistula in 1. Angiography showed fistulas of the branches of the internal pudendal artery in 2 patients and fistulas of the bulbourethral artery in 1. Microcoils were used in the bulbourethral artery and a gelatin sponge was used in other penile arteries. Complete detumescence with restored erectile function was achieved in all cases. CONCLUSIONS: High flow priapism in children can be diagnosed easily by typical clinical features combined with color Doppler ultrasound. In children with posttraumatic priapism embolization of the arteriocavernosal fistula is superior to surgical or medical procedures and should be the first line therapy. Embolization using microcoils for bulbourethral arteries and a gelatin sponge for other penile arteries has proved to be safe and successful therapy.
Subject(s)
Priapism/physiopathology , Age Factors , Child , Humans , Incidence , Male , Priapism/diagnosis , Priapism/epidemiology , Priapism/therapy , Regional Blood FlowABSTRACT
OBJECTIVE: Our purpose was to describe the morphologic appearance of musculoskeletal lesions in patients with cystic echinococcosis shown by CT and MR imaging. CONCLUSION: Patients with musculoskeletal lesions of cystic echinococcosis typically have cystic structures in adjacent soft tissues. These cysts morphologically resemble abscesses, with peripheral uptake of contrast medium and variable signal intensities on T1-weighted MR images. The absence of calcifications or endovesicular daughter cysts does not exclude the diagnosis of cystic echinococcosis.