External Ear Conditions (Diffuse External Otitis)

What is Diffuse External Otitis?

An infection of the external ear canal is a very common condition. The most common causes include trauma, such as from digging and scratching; swimming (also known as Swimmer's ear); and overuse of antibiotic eardrops. Patients suffering from eczema of the external ear canal are predisposed to infection, usually as a result of hypersensitivity and trauma. The pathogens involved include bacteria such as Pseudomonas aeruginosa and Staphylococcus aureus and fungi such as Aspergillus niger and Candida albicans.

Clinical Features

The patient's main complaints include otalgia (pain), otorrhoea (discharge) and deafness. Acute infections that do not settle within three weeks are then considered to be chronic. When examining the ear, the canal is swollen and filled with debris and discharge (greenish suggests Pseudomonas, creamy suggsts fungal). The tympanic membrane may not be visible but is usually intact although it may be swollen with granulations (granular myringitis).

Investigation

Generally, investigations are not warrented in a simple acute infection. If the condition becomes protracted with little improvement, the discharge should be cultured and sensitivities determined. Rarely is it necessary to biopsy granulation tissue to exclude more sinister conditions.

Management

The key to sucess in managing external ear conditions is regular and meticulous aural toilet. The best method for this is microsuction. If the canal is very swollen, a pope wick is inserted to hasten recovery. Once the ear canal is cleaned, antibacterial or antifungal ear drops should be prescribed, ideally with the addition of a steroid (e.g. Sofradex 5 drops tds for 10 days, or Canesten 5 drops tds for 10 days). Patients should be advised not to swim during the treatment period and to avoid water entering the ear canal during bath time. I recommend using some cotton wool mixed with hand lotion as an earplug during baths. Patients should be reviewed at two-week intervals, and more often for severe infections. Education is also important in preventing future episodes.

External Ear Conditions (Wax)

Introduction

A famous otologist in the mid-nineteenth century classified all cases of deafness into two categories: that due to wax, which could be cured; and all the others which were incurable. Happily, we have come a long way since then, but removal of occluding wax from the ear canal can still be a very rewarding procedure.

What is Wax?

Wax is produced only in the outer half of the meatus and normally it migrates out of the ear along with the desquamating cells of the canal skin. However those who 'dig at' their ears tend to push it back in again until either the build up occludes the canal, or almost occluded canal becomes completely occluded when water, or ear drops, complete the closure. It is only when the canal is completely occluded that wax causes significant hearing loss, which can be very disturbing.

Management

The treatment is removal of the wax and usually this can be done by simple syringing, so long as there are no contraindications such as a known pre-existing perforation. This is best carried out by using water at body temperature, directing the flow along the posterior canal wall, not directly at the ear drum, and ensuring that the water pressure is not dangerously high. This procedure usually produces an immediately grateful patient.
If syringing is unsuccessful or if there is a pre-existing perforation, manual removal is requried. This is best done by visualization under a microscope and extration of the wax either with a hook or, if the wax is soft, a sucker.
It has to be acknowledged that many doctors use ear drops to soften wax or partially dissolve it before either syringing or manually removing it. In actual fact, this is almost never necessary.

Complications

Careless syringing or inexperienced probing of the ear canal can cause innumerable problems, ranging from a simple perforation to a dead ear. Most of these can be avoided. It is important to be aware of the dangers from the patient moving the head at an inappropriate time.

External Ear Conditions (Keloid)

What is Keloid?

Keloids are overgrowth of fibrous or scar tissue resulting from trauma. They are raised and reddish and are the result of excessive activity of fibroblasts after injury. In general, the darker skinned races are genetically predisposed to the development of keloids.


Symptoms and Signs

Patients will present with painless raised nodules over an injury site, usually a pierced ear hole. The keloid can be itchy and bleed and may become pigmented.


Management

The effective treatment is a topic of controversy. Many modalities have been employed and include excision, steriod injection, cryosurgery, laser surgery and radiation therapy. I have found it most effective to excise the keloid with a cold knife and inject the wound with steriods every few weeks for up to six months post-excision.

External Ear Conditions (Pinna Haematoma)

What is Pinna Haematoma?

Pinna haematoma is a collection of blood between the cartilage and the covering perichondrium. Trauma is the usual cause. Contact sports such as boxing, rugby and soccer are commonly associated with this condition.


Symptoms and Signs

There is swelling of the ventral aspect of the pinna, generally located at the superior part although any portion can be involved. Unless very tense, the swelling is not very tender or warm to the touch.


Management

The principle in the treatment is to remove blood collection. This can be done either by aspiration or incision and drainage. The latter is more commonly employed as it gives better results although the former is easily performed in a clinic setting. Once teh blood has been evacuated, firm dressing or sutures are used to keep the skin and perichondrium in contact with the cartilage. This is important to prevent re-accumulation of blood. Unless infected, antibiotics need not be prescribed.


Complications

"Cauliflower ear" results from secondary organization of a residual blood clot or devascularization of cartilage and can be cosmetically deforming.

External Ear Conditions (Perichondritis)

What is Perichondritis?

Perichondritis is an infection involving the lining (perichondrium) of the cartilage of the pinna. Common causes include injury, insect bites, pierced ears and burns. These infections are more common in patients with diabetes mellitus and weakened immune systems. The most common organism is Pseudomonas aeruginosa although Staphylococcus aureus sometimes can be found. The condition results in inflammation and swelling of the perichondrium.

Symptoms and Signs

Pain, warmth and swelling are the usual complaints. The swelling and erythema are generally limited to the cartilaginous portion of the pinna, leaving the lobule untouched. The pinna is tense, warm and tender to touch. Generally, there is no fluctuation. The cause can sometimes be seen in the form of a puncture wound or burn.

Management

In the early stages, oral antibiotics may suffice. Ciprofloxacin 250 mg bd for 10 days can be prescribed in addition to medication for pain relief. For more severe infections, itravenous antibiotics may be required. Occasionally, the infection is complicated by a collection of pus between the cartilage and the perichondrium (subperichondrial abscess) which requires surgical drainage.

Complications

The cartilage of the pinna derives its nutrients from its perichondrium. When the perichondrium is infected or, worse, separated from the cartilage by pus, the cartilage begins to degenerate. If this process is allowed to progress, the cartilage may shrivel and die, resulting in a "cauliflower ear".