Behnke and his wife knew he needed to go to the ER, where doctors used a new technology — a transcranial doppler (TCD) — to perform an ultrasound on Behnke's brain. "In Troy's case ...

Intervention Transcranial Doppler ultrasound indexed PCA-CBV during a series of visual tasks. Participants closed their eyes (20-seconds) and, when prompted, opened their eyes to complete a visual ...