Multigate transcranial Doppler ultrasound system with real-time embolic signal identification and archival.
An integrated system for acquisition and processing of intracranial and extracranial Doppler signals and automatic embolic signal detection has been developed. The hardware basis of the system is a purpose-built acquisition/processing board that includes a multigate Doppler unit controlled through a computer. The signal-processing engine of the system contains a fast Fourier transform (FFT)-based, spectral-analysis unit and an embolic signal-detection unit using expert system reasoning theory. The system is designed so that up to four receive gates from a single transducer can be used to provide useful reasoning information to the embolic signal-detection unit. Alternatively, two transducers can be used simultaneously, either for bilateral transcranial Doppler (TCD) investigations or for simultaneous intra- and extracranial investigation of different arteries. The structure of the software will allow the future implementation of embolus detection algorithms that use the information from all four channels when a single transducer is used, or of independent embolus detection in two sets of two channels when two transducers are used. The user-friendly system has been tested in-vitro, and it has demonstrated a 93.6% sensitivity for micro-embolic signal (MES) identification. Preliminary in-vivo results also are encouraging.
Fan
Lingke
L
Medical Physics Group, Department of Cardiovascular Sciences, University of Leicester, Leicester, UK. lingke.fan@le.ac.uk
Boni
Enrico
E
Tortoli
Piero
P
Evans
David H
DH
D000328:Adult; D000465:Algorithms; D001185:Artificial Intelligence; D003199:Computer Systems; D004453:Echoencephalography / Q000295:instrumentation / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation*; D007090:Image Interpretation, Computer-Assisted / Q000295:instrumentation*; D016247:Information Storage and Retrieval / Q000379:methods*; D020766:Intracranial Embolism / Q000000981:diagnostic imaging*; D010363:Pattern Recognition, Automated / Q000379:methods*; D010865:Pilot Projects; D011873:Radiology Information Systems; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D018608:Ultrasonography, Doppler / Q000295:instrumentation* / Q000379:methods