Enhanced transcranial Doppler procedure for the Third World

Transcranial Doppler Ultrasound (TCD) measures cerebral blood flow velocities, and is commonly used to examine the arteries of the Circle of Willis in patients suspected of suffering from severe blood flow disruption to the brain. Diagnostic tools such as Computed Tomography (CT) or Magnetic Resonance Imaging (MRI) are readily accessible in developed countries but in developing countries the cost is well beyond the means of many. Likewise the expense of in-patient care is excessive in developing countries: hence some trained professionals run clinics from their homes. Due to its low costs and portability, ultrasound is the most common imaging modality for clinical diagnosis and monitoring of symptoms. TCD is therefore critical for neurological healthcare in developing countries. However, finding a suitable site (an acoustic window) to perform TCD can be very difficult or even impossible, often resulting in a time-consuming procedure to first locate an adequate site. The aim of this research is to reliably detect the optimum transtemporal acoustic window for TCD from a preliminary B-Mode (image) ultrasound scan. Once the optimized location has been established a TCD can commence at the predefined location. Three sheep heads were examined (left and right) with a Sonix RP (Ultrasonix, Canada) and raw radio frequency data was collected. The quantitative Broadband Spectral Difference (BSD) technique for attenuation-velocity was used to identify the temporal bone. The quantitative temporal bone detection methods give an alternative to blindly searching for the transtemporal acoustic window with a TCD scan by trial and error