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901.
evaluation of communication between intracranial arachnoid cysts and cisterns with phase-contrast cine MR imaging 总被引:4,自引:0,他引:4
Yildiz H Erdogan C Yalcin R Yazici Z Hakyemez B Parlak M Tuncel E 《AJNR. American journal of neuroradiology》2005,26(1):145-151
BACKGROUND AND PURPOSE: The demonstration of communication between arachnoid cysts (ACs) and the adjacent subarachnoid space is a prerequisite for their proper management. CT cisternography (CTC) is the conventional method for functional evaluation of ACs. The sensitivity of MR imaging to CSF flow has been demonstrated, but reports of the clinical usefulness of MR CSF flow techniques in this application are limited. The purpose of our study was to prospectively evaluate the accuracy of MR CSF flow study as an alternative to CTC in this setting. METHODS: MR CSF flow study with retrospective ECG-gated 2D, fast low-angle shot, phase-contrast (PC), cine gradient-echo sequence was performed in 39 patients with an intracranial AC. Results were compared with intraoperative and CTC findings. RESULTS: PC cine MR imaging results were compatible with operative or CTC findings in 36 (92.3%) of 39 patients. Twenty-four cysts were noncommunicating, and 15 were communicating. Three cysts were evaluated as being noncommunicating on PC cine MR imaging (false-negative) but demonstrated contrast enhancement on CTC. No false-positive diagnoses occurred. All cysts regarded as being communicating on PC cine MR imaging were also found to be communicating on both confirmation methods. CONCLUSION: MR CSF flow imaging with a PC cine sequence can be incorporated in the imaging work-up of ACs. This is a reliable alternative to invasive CTC for the functional evaluation of ACs. 相似文献
902.
Purpose: Simultaneous coronary artery bypass grafting with a resection of left atrial myxoma has been rarely reported. The ages and
the symptoms of patients who have left atrial myxomas and coronary artery disease are similar. In this report, we present
our cases of left atrial myxoma with concomitant coronary artery disease who were all treated surgically.
Methods: Between September 1998 and January 2001, 11 patients were surgically treated after being diagnosed to have left atrial myxoma.
Routine coronary angiography was performed on all patients preoperatively. In four patients concomitant coronary artery disease
was identified. At surgery we performed coronary artery bypass grafting after a resection of left atrial myxoma in three patients.
Results: All patients were weaned from cardiopulmonary bypass without any difficulty. The postoperative course was uneventful. The
follow-up period was 17 ± 10 months (range 3–32 months). All patients were symptom-free and no recurrence of myxoma was detected.
Conclusion: Based on our experience, cardiovascular surgeons should be aware of the concomitance of these diseases. It is therefore recommended
that coronary angiography should be performed on all patients who present with left atrial myxomas.
Received: November 5, 2001 / Accepted: September 3, 2002
Reprint requests to: N. Erdil
This paper was presented at the World Society of Cardio-thoracic Surgeons 11th World Congress in Sao Paulo, Brazil (August
12–15, 2001) 相似文献
903.
904.
Ozer N Kepez A Kaya B Kiliç H Deniz A Arslan U Atalar E Ovünç K Aksöyek S 《The international journal of cardiovascular imaging》2008,24(2):141-147
Aim The present study was designed to determine the reliability of the analysis of the time difference between onset of mitral
inflow and onset of early diastolic mitral annulus velocity and mean systolic strain index, and comparing them with E/E′ in
the detection of increased left ventricular end-diastolic pressure (LVEDP) in patients with coronary artery disease.
Methods Eighty patients (mean age: 57.2 ± 11.5 years) referred for cardiac catheterization were studied. Patients were divided into
2 groups according to LVEDP (group 1: LVEDP > 20 mmHg, n = 39 patients; group 2: LVEDP ≤20 mmHg, n = 41 patients). From the mitral inflow, peak E velocity was calculated. With tissue Doppler echocardiography, early diastolic
velocity (E′) measured from the septal, lateral, inferior and lateral mitral annulus and mean value of E′ and E/E′ ratio were
calculated. The time difference between onset of mitral inflow and onset of early diastolic mitral annulus velocity (TE′-E) was calculated. From the apical chambers, the peak systolic strain value of 16 left ventricular (LV) segments was measured
and the mean of these 16 segments was calculated and referred to as mean systolic strain index.
Results The patients with increased LVEDP (group 1) had a higher E/E′ ratio (13.8 ± 3.4 vs. 9.9 ± 2.8, P < 0.001) and lower mean systolic strain index (11.8 ± 3.4 % vs. 13.5 ± 3.6 %, P = 0.038) than patients in group 2. The sensitivity of E/E′ > 13.42 for identifying LVEDP > 20 mmHg was 71%, with a specificity
of 89%. The sensitivity of a mean systolic strain index < 10.57% for identifying LVEDP > 20 mmHg was 44%, with a specificity
of 83%. TE′-E was not significantly different between the two groups.
Conclusion The decreased longitudinal function of the left ventricle is related to increased LVEDP. The E/E’ ratio, which in recent years
has been used for the prediction of LV filling pressures, was a better predictor for increased LVEDP than the mean systolic
strain score index and the time difference between onset of mitral inflow and onset of early diastolic mitral annulus velocity
in patients with coronary artery disease. 相似文献
905.
Harun U?uz 《Journal of medical systems》2012,36(1):61-72
Listening via stethoscope is a primary method, being used by physicians for distinguishing normally and abnormal cardiac systems. Listening to the voices, coming from the cardiac valves via stethoscope, upon the flow of the blood running in the heart, physicians examine whether there is any abnormality with regard to the heart. However, listening via stethoscope has got a number of limitations, for interpreting different heart sounds depends on hearing ability, experience, and respective skill of the physician. Such limitations may be reduced by developing biomedical based decision support systems. In this study, a biomedical-based decision support system was developed for the classification of heart sound signals, obtained from 120 subjects with normal, pulmonary and mitral stenosis heart valve diseases via stethoscope. Developed system was mainly comprised of three stages, namely as being feature extraction, dimension reduction, and classification. At feature extraction stage, applying Discrete Fourier Transform (DFT) and Burg autoregressive (AR) spectrum analysis method, features, representing heart sounds in frequency domain, were obtained. Obtained features were reduced in lower dimensions via Principal Component Analysis (PCA), being used as a dimension reduction technique. Heart sounds were classified by having the features applied as input to Artificial Neural Network (ANN). Classification results have shown that, dimension reduction, being conducted via PCA, has got positive effects on the classification of the heart sounds. 相似文献
906.
Tatjana Dill Gerhard Dobler Elmar Saathoff Petra Clowes Inge Kroidl Elias Ntinginya Harun Machibya Leonard Maboko Thomas L?scher Michael Hoelscher Norbert Heinrich 《Emerging infectious diseases》2013,19(2):317-320
Rickettsioses caused by typhus group rickettsiae have been reported in various African regions. We conducted a cross-sectional survey of 1,227 participants from 9 different sites in the Mbeya region, Tanzania; overall seroprevalence of typhus group rickettsiae was 9.3%. Risk factors identified in multivariable analysis included low vegetation density and highway proximity. 相似文献
907.
Ramazan Akdemir ?zlem Karakurt Salih Orcan Nihat Karakoyunlu Mustafa Mucahit Balci Levent Sa?nak Hamit Ersoy Mehmet Bulent Vatan Harun Kilic Ekrem Yeter 《Asian journal of andrology》2012,14(5):784-787
Acute ST elevation myocardial infarction has high mortality and morbidity rates. The majority of patients with this condition face erectile dysfunction in addition to other health problems. In this study, we aimed to investigate the effects of two different reperfusion strategies, primary angioplasty and thrombolytic therapy, on the prevalence of erectile dysfunction after acute myocardial infarction. Of the 71 patients matching the selection criteria, 45 were treated with primary coronary angioplasty with stenting, and 26 were treated with thrombolytic agents. Erectile function was evaluated using the International Index of Erectile Function in the hospital to characterize each patient''s sexual function before the acute myocardial infarction and 6 months after the event. The time required to restore blood flow to the artery affected by the infarct was found to be associated with the occurrence of erectile dysfunction after acute myocardial infarction. The increase in the prevalence of erectile dysfunction after acute myocardial infarction was 44.4% in the angioplasty group and 76.9% in the thrombolytic therapy group (P=0.008). In conclusion, this study has shown that reducing the time of reperfusion decreases the erectile dysfunction prevalence, and primary angioplasty is superior to thrombolytic therapy for decreasing the prevalence of erectile dysfunction after acute myocardial infarction. 相似文献
908.
Ekaterina Laukhtina Marco Moschini Wojciech Krajewski Jeremy Yuen-Chun Teoh Guillaume Ploussard Francesco Soria Florian Roghmann Mara Anna Muenker Mathieu Roumiguie Mario Alvarez-Maestro Vincent Misrai Alessandro Antonelli Alessandro Tafuri Giuseppe Simone Riccardo Mastroianni Hongda Zhao Razvan-George Rahota David D'Andrea Keiichiro Mori Simone Albisinni Pierre I. Karakiewicz Harun Fajkovic Dmitry Enikeev Francesco Montorsi Shahrokh F. Shariat Benjamin Pradere the European Association of Urology - Young Academic Urologists : Urothelial Carcinoma Working Group 《BJU international》2023,131(5):571-580