99214     Detailed office visit

92541       Nystagmus
Spontaneous nystagmus test, including gaze and fixation nystagmus, with recording.

Spontaneous nystagmus tests document and measure the inability of the eyes to maintain a static position as a result of peripheral, CNS or congenital abnormality. The tests are conducted with the eyes open and closed and in ‘eyes forward’ as well as ‘eyes right’ and ‘eyes left’ positions.

These spontaneous nystagmus tests document and measure the inability of the eyes to maintain a static position when the head is in different positions. These tests are valuable to document and quantify patient complaints of dizziness in certain situations or positions. Moreover, they are sometimes helpful to localize the abnormality as CNS or peripheral.

The caloric tests evaluate the viability of the peripheral end organs by stimulating them with warm and cool water while the patient’s eyes are closed. The resulting dizziness and nystagmus is taken as an index of the viability of the organ. The eyes are then opened to evaluate the ability of the CNS to visually sup

The optokinetic test documents and measures eye movements as the patients watches a series of targets moving simultaneously to the right and then to the left. The optokinetic mechanism is at work when the visual movement in one direction encompasses more than a single point.

This test evaluates the ability of the patient to keep a moving visual target registered on the fovea. The patient watches a light as it moves back and forth in a smooth pendular fashion. The computer computes the gain (target velocity divided by eye velocity) and compares the gain to age matched norms.

This is a computerized test of the Vestibulo-Ocular Reflex (VOR), the neural mechanism that keeps a visual image registered on the fovea during head movement. It evaluates the three functional components of the VOR system: the peripheral end organ, the vestibular nuclei of the brain stem and the higher central vestibular connections. The test is accomplished by having the patient shake his head "no" and "yes" while wearing EOG electrodes that monitor eye position and a small angular velocity sensor that measures head velocity. From this data the computer computes three characteristics of the VOR: gain (ratio of eye velocity to head velocity), phase (the number of degrees by which the eye ‘misses’ the target), and asymmetry (a comparison of gain moving right with gain moving left). This information is useful for evaluating patients with balance disorders.

This is a computerized slow harmonic acceleration rotation test to evaluate the integrity of the vestibular-ocular system. The test lasts for 30-40 minutes and is completely run under computer control. This is an essential part in the evaluation of the dizzy patient as it reflects the relationship between natural head and eye movements involved in the balance mechanism.

92547   Vertical Leads
Use of vertical electrodes in any of all of the above tests counts as 1 additional test

92599 Videonystagmography goggles

92599  DIX-HALLPIKE TEST

Test that measures the presence direction of induced torsional nystagmus in response to repositioning the patient from an upright position into a supine position with the head  situated slightly lower  than the rest of the body. This is done with the head tilted 45 degrees to the right, then again with the head tilted 45 degrees to the left.