Ear otoscopy: what is it?

In otorhinolaryngology, a special diagnostic procedure, otoscopy, is performed to examine the external auditory canal and examine the tympanic membrane.

Indications for the procedure

Otoscopy is performed during routine medical examinations, as well as for patients with complaints of  ear pain , ringing or tinnitus, discomfort or itching in the external ear canal, otorrhea (discharge from one or both ears) and hearing loss.

In addition, with the help of otoscopy, appropriate medical procedures are carried out as directed: foreign bodies are removed from the ear canal and accumulated exudate or pus is removed from the middle ear cavity (located behind the eardrum) - making a puncture of the tympanic membrane (paracentesis) or opening it (tympanotomy or myringotomy) ).

Otoscopy of the ear and tympanic membrane (membrana tympani), which separates the external auditory canal from the middle ear (auris media), allows to assess the state of visible anatomical structures and diagnose inflammation of the ear canal and  diseases of the middle ear , including  acute otitis media  and its complications; purulent otitis media, including chronic.

With the help of visualization, perforation of the tympanic membrane of  any etiology is detected , as well as  otomycosis (fungal infection of the ear, fungal otitis media) .

Preparation

Accumulation of earwax - a  sulfur plug  during otoscopy prevents it from being carried out, therefore preparation for the procedure consists in the doctor removing sulfur and cleaning the external auditory canal from skin scales (keratin debris), crusts, etc.

If the procedure is scheduled in advance, it is recommended to postpone washing your ears or using ear drops.

Technique of the otoscopy

The technique of examining the external auditory canal and tympanic membrane has long been developed, but the types of otoscopy may determine some of its options.

The classic type of otoscopy is with the help of an ear funnel (ear mirror), a head reflector (a round mirror with a hole in the center) and an electric lamp, the light of which reflects a reflector. Medical headlights with batteries or rechargeable batteries are now used. [1]

A more modern examination of the ear is a special monocular otoscope (consisting of a handle and a head), at the front end of which there is a nozzle for disposable plastic ear funnels, and in the head there is an autonomous light source and a lens with three times magnification.

Video otoscopy or endoscopic otoscopy - using a digital optical otoscope (with a light source and a miniature video camera) inserted into the external auditory canal - allows the doctor to receive a clear image on a color monitor.

Pneumatic otoscopy is used to determine the mobility of an intact tympanic membrane during an induced change in pressure, which is provided by a pneumatic balloon connected to the otoscope. The immobility of the tympanic membrane in response to pressure can be caused by fluid in the middle ear, and this type of otoscopy is considered the main one in the diagnosis of  exudative otitis media . A pneumatic otoscope can also be helpful in differentiating the degree of perforation of the tympanic membrane. [2]

Visualizing the ear canal and tympanic membrane with a binocular microscope (with the patient lying on their back with their head tilted) is called microscopic otoscopy or otomicroscopy. It provides a wider field of view and 40x magnification of anatomical structures.

Before starting an otoscopic examination, an experienced physician will check the condition of the facial (VII cranial) nerve passing through the middle ear: the patient is asked to smile, frown, puff out his cheeks, and raise his eyebrows with closed eyes. Then a physical examination of the auricle (with its palpation) and behind the ear is performed.

The sequence of actions - otoscopy algorithm - includes:

• choosing an ear funnel that is the right size for a particular patient's ear canal;
• the introduction of the funnel with the straightening of the external auditory canal, for which in adult patients the auricle is pulled backward and upward, and in children - backward and downward. Only after this is the ear speculum carefully inserted into the ear canal, and the doctor examines it;
• Slowly advance the funnel of the otoscope into the canal until the tympanic membrane becomes visible and is assessed for color, bulge, and perforation. Also, the doctor observes the so-called landmarks of the tympanic membrane: a three-layer stretched part (pars tensa), a two-layer loose part (pars flaccida) and a malleus handle (malleus) - the largest auditory bone in the middle ear, adjacent to the tympanic membrane;
• slow extraction of the funnel from the ear canal.

Otoscopic signs of otitis media and other diseases

What can a doctor see with an otoscopy? If there is no otitis media and other ear diseases, otoscopy is normal means visualization at the end of the external auditory canal of a normal tympanic membrane - a translucent pale gray (whitish) oval membrane (in childhood it is round).

In acute otitis externa, the skin of the ear canal is painful and swollen, and visualization of the eardrum may not be possible.

In the early stages of acute otitis media, the eardrum changes depending on the stage of the disease. At first it is pink, retracted, with expansion of peripheral vessels. As the inflammatory process progresses, the tympanic membrane swells up, becomes bright red; its perforation is possible with the outpouring of pus into the external auditory canal. [3]

With exudative otitis media, the tympanic membrane is retracted and immobile, and due to serous effusion, it becomes yellowish.

Read also -  Diagnosis of acute otitis media

Otoscopy for  chronic purulent otitis media  is able to reveal both its forms: mesotympanitis and epitympanitis. The main otoscopic signs of mesotympanitis are through perforation of various shapes and sizes of the stretched part of the tympanic membrane with its redness and swelling and / or granulation along the edges of the opening. And epitympanitis is characterized by a violation of the integrity of the tympanic membrane from the edges of its unstretched part.

Otoscopy for otomycosis reveals fluffy-looking particles of white or cream color. If the infection is caused by Aspergillus niger, tiny grayish-black outgrowths of mycelium can be identified.

The growth of new cancellous bone tissue around the base plate of the stapes of the middle ear in the area of the oval window - otosclerosis - is difficult to diagnose during otoscopic examination, since the pathological process develops in the tympanic cavity. And the otiatrist can observe a change in the color of the tympanic membrane and its thinning, as well as redness of the mucous membrane covering the tympanic cavity (which is visible through the tympanic membrane).

Mastoiditis is an inflammation of the mastoid process (processus mastoideus) of the temporal bone of the skull located behind the ear, the tympanic and scaly parts of which limit the auditory opening and the external auditory meatus on three sides - during otoscopy, it visualizes the deformation of a part of the wall of the external auditory canal formed by the tympanic and squamous bones. The main method of instrumental diagnosis of this disease is MRI. [4]

Contraindications to the procedure

Otoscopy is performed in children of any age and adults. In addition to the technical complexity in case of anatomical anomalies of the ears and stenosis of the external auditory canal, severe swelling of the ear canal and the presence of strong bloody, sacral or purulent discharge from the ear canal are considered contraindications for its implementation. [5]

Complications after the procedure

Inserting the speculum into the ear canal can cause reflex dilation of the blood vessels supplying the eardrum, resulting in temporary redness in the ear.

Due to the frequent use of ear specula and otoscopes, they represent a potential source of pathogens. And the consequence after the procedure - without proper disinfection of the instruments - may be the development of an infection.

When the otoscope is inserted too deeply into the ear canal, or the patient has a very thin eardrum, there is little risk of damage.

Patients with membrane perforation or rupture of one of the membranes separating the middle and inner ear (perilymphal fistula) may have complications after pneumatic otoscopy in the form of dizziness, imbalance, nystagmus, nausea and vomiting.

Care after the procedure

Diagnostic otoscopy does not require post-procedure care or rehabilitation.

Reviews

Feedback from ENT doctors confirms the value of information about a possible disease of the middle ear, obtained by direct observation of the tympanic membrane and external auditory canal through the otoscope, which allows you to accurately determine the cause of the patient's complaints.