Ictal eye closure is a reliable indicator for psychogenic nonepileptic seizures

Chung et al [1] have underlined the useful clinical features of "eyes open" versus "eyes closed" seizures. Another simple and rapid bedside technique that I have found helpful is not emphasized in discussions on clinical features of psychogenic events. The oculocephalic reflex has been reviewed by Plum and Posner [2] in the setting of neurologic and psychogenic coma and a similar approach should apply to the patient during an epileptic or psychogenic seizure.

It is essentially impossible for a patient to mimic the eye movements or positions of either the absent oculocephalic reflex or the uninhibited reflex. Roving eye movements cannot be voluntarily generated and are a signature of neurologic not psychiatric conditions. During a psychogenic event, the patient will display random saccadic eye movement with head rotations, indicative of a brain that is "awake."

Alternatively, an uninhibited vestibulo-ocular or oculocephalic reflex, or absence of reflex indicates a neurological event of some type--possibly a pseudoseizure but not a psychogenic seizure.

This evaluation also applies to the nonconvulsive status patient as a "one-way" interpretation--if an uninhibited or absent oculocephalic reflex is documented the event is due to a neurological or medical cause. On the other hand, it is likely that an inhibited response with generation of random saccadic eye movements could occur in patients with fluctuating levels of consciousness and frequent but distinct seizures, as opposed to electrically continuous nonconvulsive status epilepticus. A simple partial seizure would show the features of wakefulness. Recall that medications, inappropriately given for psychogenic seizures, may produce the neurologic pattern of ocular movement.

It is the rare patient that would be so rigid that standard head rotation could not be done. In this case oculovestibular testing would be performed, or a "log-roll" technique could be used with the assistance of medical staff.

Cold calorics should produce nystagmus in the psychogenic seizure patient who displays tonic eye deviation in any direction. Furthermore, if the eyes are deviated, the psychogenic patient would not be able to maintain the tonic position during variable frequency oculocephalic maneuvers or oculovestibular testing. These are also useful tests in the patient with a combination of epileptic and nonepileptic events.

References

1. Chung, S, Gerber P, Kirlin. Ictal eye closure is a reliable indicator for psychogenic nonepileptic seizures. Neurology 2006;66: 1730 -1731.

2. Plum F, Posner J. Stupor and Coma. F.A. Davis, Philadelphia; 1980.

DISCLOSURE: The author reports no conflicts of interest.

We thank Dr. Bounds for his comments and concur that various clinical features can help determine epileptic vs. non-epileptic seizures including oculocephalic maneuver and oculovestibular testing. However, many of these tests have to be performed by physicians during seizures which limit their practical usefulness.

The main goal of our study was to identify a reliable indicator for NES based on simple observation, specifically eye closure or opening. This indicator can be quite useful in an outpatient clinic where one can identify likely NES based on the description of seizure semiology by untrained observers.

Disclosure: The authors report no conflicts of interest.