A 21-year-old man went to the doctor after noticing that his left eye was increasingly protruding from his skull, only to find out that he had a cyst behind his eye, which had been caused by his chewing.
The rare situation, described in last week, occurred due to a skull defect that allowed the movement of the jaw to put undue pressure on the structures around the eye, disrupting his vision.
The patient first visited an ocuplasty clinic -- a clinic which performs cosmetic surgery on eyes -- complaining that his left eye had been slowly bulging more and more from his face over the last 18 months.
He was also experiencing oscillopsia, unstable vision in which the world around a person appears to be moving when it is actually stationary.
There was no pain associated with the eye鈥檚 new forward position, and when doctors investigated, they found there was no difference between the vision in his eyes, and was able to move all his eye muscles. .
When doctors dilated his eyes to inspect the back of the eyeball, they saw no glaring issues, but there was visible bulging of the left eye of around three millimetres.
Eventually, doctors discovered the issue stemmed from a mass in the intraconal space, a region in the muscles directly behind the eyeball itself, but at weren鈥檛 sure what it was. They believed that it was either made up of a tangle of bleeding capillaries, a tumour within the nervous system itself, or a dermoid cyst containing fluid.
The third option turned out to be the culprit: CT scans revealed a cystic lesion in the patient鈥檚 left eye measuring two centimetres long and two centimetres wide.
Doctors realized that a pre-existing bone defect in the patient鈥檚 eye socket was allowing this cyst to extend into a skull structure called the infratemporal fossa, which nerves pass through, thus displacing the optic nerve itself.
Once the problem was isolated, the question turned to how the cyst had gotten there.
Further examination of the patient showed that the bulging of his eye, which persisted even when he was at rest, got worse when he was chewing.
鈥淥n repeated chewing movements, the eyeball was seen wobbling in anteroposterior direction,鈥� the case report stated.
They were able to surgically remove the cyst, after which the patient reported that the oscillopsia had ceased and the bulging was gone.
Dermoid cysts are the most common type of orbital tumours seen in infants and children, according to the case report, and dumbbell dermoid cysts make up around six per cent of all dermoid cysts.
In order for a person鈥檚 chewing to cause oscillopsia, they must also have a defect in the bones around the eye itself, the case study clarified.
If a patient has this bone defect, then the movement of the jaw can push soft tissue into the eye or the muscles and nerves behind it.
In three years of follow-up after the patient鈥檚 surgery, there has been no recurrence in either oscillopsia or the eyes protruding.
鈥淚 am happy that I don鈥檛 any more have the visual problem and facial disfigurement,鈥� the patient said in the case report. 鈥淚 am grateful to the entire team of doctors for their care.鈥�
The case report鈥檚 authors stated that this highlights the importance of asking patients about their history of chewing and whether their vision changes during chewing.
