While both recording technologies are available in our lab, we use video on about 75 percent of our patients. Before testing we decide which technique will be utilized by looking at the patient's face and eyes. If eyelashes interfere with our view of the pupil, an eyelash curler is employed. We occasionally switch from one technique to the other mid-test, most commonly switching to electrodes if patients cannot keep their eyes open during video recordings. The core balance test battery also adds a screening test of postural control.
Patients pass the test if they have ankle sway without fall reactions on all conditions.
They fail if there is a fall reaction or switch to hip strategy on any condition. This brief screening test should be performed with every ENG battery to investigate the motor output of the balance system. It is important to keep in mind that the majority of ENG tests are normal. Stockwell recently reported results from a series of 2,584 ENGs performed at a wide range of private and hospital-based laboratories. Normal results were obtained in 61 percent, and another 10 percent had only non-localizing findings.