When 30-year-old Terence Chan looked in the mirror one day, he noticed that part of his left ear was strangely swollen. He did not remember injuring it during his regular karate sessions or on any other occasion.
Despite the swelling, the ear did not look injured, as there was no bruise, redness or pain.
Although he was not much bothered by the swelling, Chan (real name withheld for patient confidentiality reasons) decided to smear some antibacterial ointment on it, thinking it might be an infection of some sort.
Over the next two to three weeks, the size of the swelling continued to increase until half his ear appeared to be encased in a skin bubble. He finally decided to see a doctor.
The general practitioner he consulted used a fine needle to pierce the bubble and drained some blood from it. The swelling deflated, and the doctor sent him away with oral antibiotics.
But a few days later, the swelling returned and continued to grow. As there was still no pain or redness, Chan tried to ignore it.
After another two or three weeks of continued swelling, however, he decided to go back to see the doctor, who then referred him to an ear, nose and throat specialist, Dr Paul Lam Kin-yip. When Lam saw the condition of Chan's ear, he knew straight away that the internal structure of the ear had been damaged.
The external part of the ear that protrudes from the head is called the pinna. It is made of soft cartilage, which gives it form. A dense membrane of fibrous connective tissue called perichondrium wraps around the cartilage, nourishing it with oxygen and nutrients via a web of tiny blood capillaries. Skin sits on top of the perichondrium.
Chan's perichondrium had become detached from the cartilage. This can happen as a result of an injury where a shearing or glancing blow was applied to the ear, or if the ear was subjected to repeated friction, such as when a wrestler's ear is repeatedly pressed and dragged on a mat. It could even have happened because of excessive scratching, as was the case with one of Lam's other patients.
When the perichondrium tears away from the cartilage, it creates a cavity between the two layers where blood and fluid collects in a condition called haematoma.
With no place for the fluid to go, the elastic skin encasing the ear starts to balloon, creating the mysterious swelling that Chan experienced.
Lam noted that Chan's ear had the classic presentation of an auricular haematoma - the swollen area had a slight blue tinge, and Chan felt no pain when Lam pressed on the swelling. In fact, Lam could feel the fluid under the skin moving as he pressed on the distended area.
Untreated auricular haematoma can result in an irreversible ear deformity known as cauliflower ear or boxer's ear. If Chan had allowed his condition to drag on, the cartilage in his ear would have collapsed.
Thankfully, once diagnosed, auricular haematoma is not difficult to treat.
Lam used a simple outpatient procedure called incision and buttoning to repair the damage to Chan's ear.
First, he made a small incision in the folds of Chan's ear. He then drained the blood and other liquid from the cavity and washed the area out with saline.
Lam found that part of the perichondrium had already formed scar tissue called fibrosis, which needed to be trimmed away, as it could not reattach to the cartilage.
The cartilage had also thickened slightly from the trauma, but it remained healthy. Lam then closed the incision.
To ensure that the ear retained its normal shape, Lam took dental rolls - cigarette-shaped packed cotton - and wedged them against the natural curves of the pinna.
Lam says that in the past, actual buttons were used, giving rise to the procedure's moniker, but dental rolls are now used because they are more flexible.
He then used sutures to attach the rolls to the ear. Over that, he added more protective packing.
Chan was put on antibiotics and given strict orders not to wet his left ear for two weeks while it healed.
After two weeks, he returned to have the sutures removed, and his ear looked as good as new.
Lam advised Chan to use protective headgear that covers his ears when participating in contact sports such as karate.