Cholesteatoma: A serious ear condition



What is a cholesteatoma

A cholesteatoma is a skin growth that occurs in an abnormal location, the middle ear behind the ear-drum. It is usually due to repeated infection which causes an ingrowth of the skin of the eardrum. Cholesteatomas often take the form of a cyst or pouch which sheds layers of old skin that builds up inside the ear. Over time, the cholesteatoma can increase in size and destroy the surrounding deli-cate bones of the middle ear. Hearing loss, dizzi-ness, and facial muscle paralysis are rare but can result from continued cholesteatoma growth.

How does it occur

A cholesteatoma usually occurs because of poor eustachian tube function as well as infection in the middle ear. The eustachian tube conveys air from the back of the nose into the middle ear to equalize ear pressure (clear the ears). When the eustach-ian tubes work poorly, perhaps due to allergy, a cold or sinusitis, the air in the middle ear is absorbed by the body, and a partial vacuum results in the ear. The vacuum pressure sucks in a pouch or sac by stretching the eardrum, especially areas weakened by previous infections. This sac often becomes a cholesteatoma. A rare congenital form of cholestea-toma (one present at birth) can occur in the middle ear and elsewhere, such as in the nearby skull bones. However, the type of cholesteatoma asso-ciated with ear infections is most common.

what are the symptoms

Initially, the ear may drain, sometimes with a foul odor. As the cholesteatoma pouch or sac enlarges, it can cause a full feeling or pressure in the ear, along with hearing loss. (An ache behind or in the ear, especially at night, may cause significant discom-fort.) Dizziness, or muscle weakness on one side of the face (the side of the infected ear) can also occur. Any, or all, of these symptoms are good reasons to seek medical evaluation.

Is it dangerous

Ear cholesteatomas can be dangerous and should never be ignored. Bone erosion can cause the infec-tion to spread into the surrounding areas, including the inner ear and brain. If untreated, deafness, brain abscess, meningitis, and rarely death can occur.

What Treatment can be provided ?

An examination by an otolaryngologist-head and neck surgeon can confirm the presence of a cho-lesteatoma. Initial treatment may consist of a care-ful cleaning of the ear, antibiotics, and ear drops. Therapy aims to stop drainage in the ear by con-trolling the infection. The extent or growth characteristics of a cholesteatoma must also be evaluated. Large or complicated cholesteatomas usually re-quire surgical treatment to protect the patient from serious complications. Hearing and balance tests, x-rays of the mastoid (the skull bone next to the ear), and CAT scans (3-D x-rays) of the mas-toid may be necessary. These tests are performed to determine the hearing level remaining in the ear and the extent of destruction the cholestea-toma has caused. Surgery is performed under general anesthesia in most cases. The primary purpose of the surgery is to remove the cholesteatoma and infection and achieve an infection-free, dry ear. Hearing preser-vation or restoration is the second goal of surgery. In cases of severe ear destruction, reconstruction may not be possible. Facial nerve repair or proce-dures to control dizziness are rarely required. Reconstruction of the middle ear is not always possible in one operation and therefore, a second operation may be performed six to twelve months later. The second operation will attempt to res-tore hearing and, at the same time, inspect the middle ear space and mastoid for residual cholesteatoma.

When Can the Ear Be Termed Disease(Cholesteatoma) Free?

If cholesteatoma is found and the canal wall is still preserved at a second stage, does this necessitate a third look to determine if cholesteatoma has not reformed? This question is large­ly unanswered by current available literature. Some sur­geons feel reformation is directly proportional to time. That is to say, the longer the ear is followed-up, the more likely it is for a cholesteatoma to be present (Arriagal, 1994). Lau and Tos (1987) use an arbitrary figure of 10 years from initial surgery to term an ear free from cho­lesteatoma if the ear was disease-free during that time. As this is a gray area, the criteria used to determine if an ear is free from disease are ill defined. As the second-stage surgery is done up to 12 months following initial surgery, another 9 years must pass before terming the ear free from cholesteatoma. To properly claim that the ear is indeed free from cholesteatoma, another surgical inspection should be done. however, most of the sur­geons who do canal wall up techniques do not do this. Advocates of the canal wall downAdvocates of the canal wall down technique point to this failing as another reason why they advocate canal wall down techniques.

Are Cholesteatomas More Aggressive in Children?

Pediatric cholesteatomas are thought to be more aggressive than adult cholesteatomas. Thus, aggressive­ness is determined by the higher rates of reformation and the rapidity with which it reforms. Reformation of cholesteatoma following canal wall up surgery is also more likely to occur in a shorter span of time in children as compared to adults

Are Cholesteatomas in Children Different From Those Found in Adults?

Histologically, they appear the same, but they dif­fer in behavior. Most available literature demonstrates that cholesteatomas are more extensive in children than in adults because children's mastoids are more cellular and this permits the cholesteatoma to be more extensive. (Edelstein & Parisier, 1989; Jansen, 1978). However, the destructive nature of cholesteatomas is directly related to the duration of time the cholesteatoma is present. The longer a cholesteatoma is allowed to reside, the more destruc­tive it becomes.

Reformation of Cholesteatoma

Reformation of cholesteatoma is higher in children than in adults. Glasscock, Dickens, and Wiet (1981) quote a figure of 23% who had reformation of cholesteatoma. Of these 10 patients, 7 were suspected to have disease, while 3 had disease that was unsuspect­ed. Although recurrent disease was also found in 23% of their patient, 7 (16%) of the patients developed recur­rence after 6 to 12 months and 3 (7%) patients developed recurrence at 12 months.

Recurrent Cholesteatoma

Recurrent cholesteatoma means that the original cholesteatoma has been removed and a new choles­teatoma has occurred all over again, independent of the previous cholesteatoma. It becomes difficult at times to be completely sure that the new cholesteatoma is actu­ally a fresh one. Vartianen and Nuutinen (1992) had a mean follow-up of 7.1 years; 17% of their patients had canal wall down surgeries. They had a reformation of cholesteatoma in 11% of these patients. Jansen (1978) reports a reformation of 7.75%, Smyth (1976) reports 24%, Charachon and Gratacap (1985) report 50%, and Jahnke and Falk (1976) report a rate of 40%. Lau and Tos (1987) operated on 122 children between 1965 and 1978. They had a 98% foilow-up. The median observation period was 11 years. In the years 1980/1981, they noted residual cholesteatoma to be in 10% of these patients while recurrence was 2%. By 1985/1986 the residual cholesteatoma was 12.2% and recurrent cholesteatoma was 4.8%. Palva, Karma, & Karja (1977) found residual cholesteatoma to be 5% in their series, with a follow-up ranging from 18 months to 10 years. One-stage intact canal wall techniques have been reported by Tos (1983). He observed his patients for a period of 2 to 16 years and had a 97% follow-up. Four­teen percent of his canal wall up patients went on to develop reformation of cholesteatoma, while 13% of the patients on whom he had performed canal wall down surgery went on to reform their cholesteatomas. Austin (1989) and Hirsch, Kamerer, and Doshi (1992) recom­mend single stage procedures. They state that 80% of patients can be controlled with single stage surgery. The remaining patients can be operated as and when the cholesteatoma reforms. They have not encountered any life-threatening complications of cholesteatoma in their series of patients.