What is cholesteatoma and the causes of Cholesteatoma?
Cholesteatoma is an ear problem that has a slow and progressive growth, destroying the bone around it and other structures of the ear, even leading to deafness.
The cholesteatoma, sometimes called keratome, is a type of cyst or nodule coated squamous epithelium similar to the scales (tissue formed by layers of cells joined together) in the middle ear and mastoid (bone mastoid of the skull behind the external auditory canal). This type of cyst can progressively spread and affect other regions of the ear, such as the ossicle chain, giving rise to the appearance of conduction deafness (this type of deafness appears when the transmission of sound in the outer ear or the ear means, medium).
The hearing loss can also occur if the cholesteatoma obstructs the fallopian tube’s ostium, leading to the accumulation of secretions in the middle ear.
Cholesteatoma can affect both ears in 4% of cases. It is a recurrent and potentially dangerous disease for the patient due to the consequences it can have. Therefore the early diagnosis is essential for a good evolution.
The actual incidence of cholesteatoma is unknown. Studies have suggested that the annual average number of cases is 5 to 15 per 100,000 children and nine issues per year per 100,000 adults. It is more common in men, especially those under 50 years of age.
In any suspicion, the person must be evaluated by the ENT specialist, who will decide the steps to follow. Regarding its treatment, most cholesteatomas require surgery, the effectiveness of which will depend on the size of the cholesteatoma. It is essential to carry out revisions after surgery since it can reappear, being a recurrent disease.
To better understand what a cholesteatoma is, it is helpful to briefly review the ear’s anatomy. According to an anatomical point of view, the ear can be divided into three parts:
External ear: made up of the pinna and external auditory canal, which amplifies sound.
Middle ear: formed by the eardrum, the chain of ossicles (hammer, incus, and stapes), the Eustachian tube, and the mastoid process.
Inner ear or labyrinth: divided into a bony labyrinth and membranous labyrinth (the latter housed within the former). Its function is to convert mechanical stimuli into electrical ones to perceive sounds.
Cholesteatoma causes and types
The cholesteatomas can be classified into congenital, acquired, and postsurgical, being the most frequently acquired (98% of cases).
Congenital cholesteatoma: It is rare and typically arises in children. It is the one that appears behind an intact eardrum in children who have not previously had diseases of the middle ear ( otitis ). The origin of the squamous epithelium in congenital cholesteatoma is a controversial issue. The most accepted theory is an alteration of embryonic development (since it is not infectious, there is some alteration in the ear’s fetal development that gives rise to the keratoma).
Acquired cholesteatoma: appear after birth, often as a result of chronic diseases of the middle ear. It can be primary or secondary.
Primary ( retraction pockets ): the most frequent. In those who have a chronic alteration in the Eustachian tube’s functioning, negative pressures are generated in the middle ear, giving rise to the formation of a retraction pocket. This progressively occupies pocket-shaped space in the middle ear, where scaly cells that form the cholesteatoma are trapped. Squamous epithelium can erode bone, affecting first the delicate chain of ossicles and then the temporal bone. Also, keratin deposits can become infected by moisture or after middle ear infections, thus causing purulent discharge in the ear.
Secondary: desquamated cells from the outer ear epithelium pass through perforations in the eardrum into the middle ear, accumulating and forming the cholesteatoma.
The factors predisposing to a cholesteatoma acquired include: a history personal of recurrent otitis media or maintained secretion in the middle ear, craniofacial malformations, family history of chronic disease of the middle ear or cholesteatoma, placement of tympanostomy tubes, different syndromes ( syndrome Turner, Down syndrome) or the existence of cleft palate.