Medical Mystery: People Who Hear Their Eyeballs Move
It sounds likeِ something outِ ofِ anِ Edgar Allen Poe tale ofِ horror.
A man becomesِ agitated byِ strange sounds onlyِ to find thatِ they areِ emanating fromِ inside hisِ own body—his heart, hisِ pulse, theِ very movement ofِ hisِ eyes inِ their sockets.
Yet superior canal dehiscence syndrome (SCDS) isِ a veryِ real affliction caused byِ a small hole inِ the bone covering part ofِ the innerِ ear.
[An edited transcript of the interview follows.]
What is superior canal dehiscence syndrome (SCDS)?
Superior canal dehiscence syndrome isِ a disorder caused byِ anِ opening inِ the bone thatِ shouldِ cover theِ innerِ ear’s top balance canal (called theِ superior semicircular canal).
The innerِ ear consists ofِ a bony labyrinth thatِ hasِ two parts: theِ cochlea, whichِ enables usِ toِ hear, andِ the vestibular labyrinth, whichِ enables usِ toِ keepِ our balance.
When theseِ areِ working properly, theyِ allowِ us toِ maintain a steady gaze andِ keep images stable onِ our retinas evenِ when ourِ heads areِ moving.
How were you able to first identify SCDS?
It wasِ a study ofِ the eye movements.
The eye movements ofِ this disorder, whichِ isِ evoked byِ sound andِ pressure, areِ quite distinctive.
If youِ haveِ a normal thickness ofِ bone, whichِ isِ aboutِ 0.6 orِ 0.7 millimeter covering theِ superior canal, that’sِ very unlikelyِ toِ everِ erode.
Does SCDS worsen over time if it is not treated?
In manyِ cases, itِ will stay atِ a certainِ level, althoughِ it’s hard toِ predict.
His mostِ disturbing symptom wasِ loud noises caused hisِ eyes toِ move, soِ he’sِ avoided loud noises.
Other people areِ more disturbed byِ the disorder.
Do people get this in both ears?
In aboutِ one thirdِ ofِ cases it’sِ bilateral whenِ diagnosed.
Usually there’sِ a moreِ symptomatic ear, andِ we treat thatِ ear firstِ (although someِ haveِ opted toِ haveِ bothِ ears treated, butِ not atِ the sameِ time).
In theِ minority, bothِ ears appearِ to beِ equally affected.
How is this treated?
The wayِ we haveِ treated thisِ disorder isِ to mechanically inactivate theِ balance canal, toِ plug itِ with fascia (the covering ofِ muscle) andِ tiny chips ofِ bone takenِ fromِ the patient.
We’ve usedِ canal plugging withِ success.
We’ve seenِ people inِ their teens andِ 20s thatِ haveِ this disorder.
Why are we hearing more about SCDS recently?
It’s beingِ better recognized becauseِ it’s beenِ in theِ medical literature now.
Most major ear centers inِ the world nowِ haveِ experience withِ itِ andِ are comfortable making theِ diagnosis.
It’s a neat story—there’s good science inِ it andِ anِ effective treatment onceِ you’ve madeِ a definitive diagnosis, andِ the outcomes tend toِ beِ very good.