Applications Of Transcranial Color Doppler Sonography And Contrast Agents In The Diagnosis Of Cerebral Aneurysms

Background and Purpose: The mobidity of aneurysms and mortality of aneurysmal subarachnoid hemorrhage are still very high. It suggested that correct diagnosis and treatment before rupture will avoid the sequalae. Transcranial color Doppler sonography(TCCS)is a new dia~tiiostic method allo~vi ng the non-invasive imaging of intracranial circulation. The purpose of this study was to evaluate its diagnostic potential in cerebral aneurysms All these studies aimed at:( 1) characterizing the TCCS sono~raphic appearance of cerebral aneurysms, (2)assessing the diagnostic potential of duple x color flow imaging in the evaluation of cerebral aneurysrns~ (3)evaluating the application of ultrasound contrast agents Levovist in cerebral aneurysms. Methods: TCCS examination was performed in 5 1 consecutive patients(male 29 and female 22,rnean age45 ?15 ). As the normal contrast, 40 healthy volunteers took part in without cardiac, cerebral and renal disease(male 20 and female ~0 mean age36?). Using Acusonl28XP/l0 equipped with a 2.0MHz sector scan transducer, the circle of Willis?and all the detachable branches were examined respectively through the temporal, ophthalmatical . occipital or frontal window. Relevant parameters such as systolic peak (Vmax), end-diastolic maximurn(Vrnin ), resistive index(RI) etc. were detected. 1 7 of 5 1 patients with insufficient temporal window were examined with contrast aQent Levovist. The intravenous injection ~vas continuous (approx 1 2ml/sec). and concentration was 2OO梸4O0mg/ml. The sonographer was blinded to the results of DSA and all the cases were confirmed by angiography . ~0 patients were followed up afier endovascular therapy with Guglielmi detachable ci ols(GDC). Results: I in 40 volunteers, only 3 were not feasible due to bone thickness by TCCS, and the normal values(X盨) were provided. 2.Cornp.ared with DSA~ TCCS showed sensitivity 75%, specificity 81%, accuracy 780o, mistake diagnostic rate 19%, omission diagnostic rate 25%. positive predictive value 6800, negative predictive value 860o, positive likelihood ratio 3.9, negative likelihood ratio 0.31, and Youden抯 index 0.56. 3. l7eases underwent UCAs Enhancement lasted 3.5~9min afier iv. The showin~t rate of aneurysms increased to 90~ o. AVM, AVE and tumor cases were clearly demonstrated even the minute structures. 4.Follow-up TCCS studies performed in 10 patients. The GDCs were identified and in the patients as hyperechoic structures of the size and shape. 6 TCCS showed no flow signal in 7 of 10 cases. In 3 cases weak flow signal still could be found in the hyperechoic structures. Conclusion: 1. TCCS had higher value in diagnosis of cerebral aneurysm and can be chosen as a method of screening diagnosis. 2. Ultrasound contrast agents Levovist improves diagnostic accuracy for intracranial aneurysms and other cerebrovascular disease. 3.TCCS is a reliable, noninvasive means to detect signs of aneurisrnal recanalization and assess parent artely afier endovascular therapy.