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Overview Tympanocentesis is a minor surgical procedure that refers to puncture of the tympanic membrane with a small gauge needle in order to aspirate fluid from the middle ear cleft or to provide a route for administration of intratympanic medications. The procedure was described in 1768 and has been used since to treat acute otitis media (AOM). It was particularly popular in the preantibiotic era, but its use has since declined. It is now used mainly for the management of complex cases that have not responded to antibiotic therapy [1] , as well as facilitating the delivery of medication directly to the middle and inner ear. Relevant Anatomy The primary functionality of the middle ear (tympanic cavity) is that of bony conduction of sound via transference of sound waves in the air collected by the auricle to the fluid of the inner ear. The middle ear inhabits the petrous portion of the temporal bone and is filled with air secondary to communication with the nasopharynx via the auditory (eustachian) tube. The tympanic membrane (TM) is an oval, thin, semi-transparent membrane that separates the external and middle ear (tympanic cavity). The TM is divided into 2 parts: the pars flaccida and the pars tensa. The manubrium of the malleus is firmly attached to the medial tympanic membrane; where the manubrium draws the TM medially, a concavity is formed. The apex of this concavity is called the umbo. The area of the TM superior to the umbo is termed the pars flaccida; the remainder of the TM is the pars tensa (see the image below). Tympanic membrane (TM): pars flaccida (superior to insertion manubrium) and pars tensa (remainder of TM). For more information about the relevant anatomy, see Ear Anatomy . Indications Tympanocentesis is a diagnostic and therapeutic procedure used in the treatment of a wide range of otological disorders, including acute otitis media, chronic otitis media with effusion , tympanic membrane retraction, sensorineural hearing loss, and Ménière disease . Indications for tympanocentesis include the following: Severe otalgia in a child with acute otitis media (AOM) - Provides immediate pain relief A toxic child with AOM - Microbiological analysis of the aspirate to isolate pathogens and establish antibiotic sensitivities AOM in neonates, particularly those nursed or discharged from neonatal intensive care units - Microbiological analysis of aspirate to isolate pathogens and establish antibiotic sensitivities AOM in an immunocompromised child or adult - Microbiological analysis of aspirate to isolate pathogens and establish their antibiotic sensitivities AOM persisting after 2 courses of appropriate antibiotics - Microbiological analysis of aspirate to isolate pathogens and establish antibiotic sensitivities [1, 2] AOM complicated by mastoiditis , bacterial meningitis , or any other intracranial complication - Allows drainage and microbiological analysis of aspirate

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OverviewTympanocentesis is a minor surgical procedure that refers to puncture of the tympanic membrane with a small gauge needle in order to aspirate fluid from the middle ear cleft or to provide a route for administration of intratympanic medications. The procedure was described in 1768 and has been used since to treat acute otitis media (AOM). It was particularly popular in the preantibiotic era, but its use has since declined. It is now used mainly for the management of complex cases that have not responded to antibiotic therapy[1] , as well as facilitating the delivery of medication directly to the middle and inner ear.

Relevant Anatomy

The primary functionality of the middle ear (tympanic cavity) is that of bony conduction of sound via transference of sound waves in the air collected by the auricle to the fluid of the inner ear. The middle ear inhabits the petrous portion of the temporal bone and is filled with air secondary to communication with the nasopharynx via the auditory (eustachian) tube.

The tympanic membrane (TM) is an oval, thin, semi-transparent membrane that separates the external and middle ear (tympanic cavity). The TM is divided into 2 parts: the pars flaccida and the pars tensa. The manubrium of the malleus is firmly attached to the medial tympanic membrane; where the manubrium draws the TM medially, a concavity is formed. The apex of this concavity is called the umbo. The area of the TM superior to the umbo is termed the pars flaccida; the remainder of the TM is the pars tensa (see the image below).

Tympanic membrane (TM): pars flaccida (superior to insertion manubrium) and pars tensa (remainder of TM).For more information about the relevant anatomy, see Ear Anatomy.

IndicationsTympanocentesis is a diagnostic and therapeutic procedure used in the treatment of a wide range of otological disorders, including acute otitis media, chronic otitis media with effusion, tympanic membrane retraction, sensorineural hearing loss, and Ménière disease.

Indications for tympanocentesis include the following:

Severe otalgia in a child with acute otitis media (AOM) - Provides immediate pain relief A toxic child with AOM - Microbiological analysis of the aspirate to isolate pathogens and establish

antibiotic sensitivities AOM in neonates, particularly those nursed or discharged from neonatal intensive care units -

Microbiological analysis of aspirate to isolate pathogens and establish antibiotic sensitivities AOM in an immunocompromised child or adult - Microbiological analysis of aspirate to isolate pathogens

and establish their antibiotic sensitivities AOM persisting after 2 courses of appropriate antibiotics - Microbiological analysis of aspirate to isolate

pathogens and establish antibiotic sensitivities[1, 2]

AOM complicated by mastoiditis, bacterial meningitis, or any other intracranial complication - Allows drainage and microbiological analysis of aspirate

Suspected presence of cerebrospinal fluid in the middle ear cleft (spontaneous and secondary to trauma) - Aspirate for biochemical analysis

Access for the administration of intratympanic medications such as corticosteroids (in patients with sudden sensorineural hearing loss) or administration of intratympanic gentamicin (for the treatment of severe Ménière disease)

To establish whether insertion of a ventilation tube would improve the hearing of patients with chronic otitis media with effusion

To establish whether insertion of a ventilation tube would elevate a retracted tympanic membrane

ContraindicationsTympanocentesis is a safe procedure often performed under local anesthetic in the outpatient clinic setting. However, the procedure does have a few contraindications. Contraindications include the following:

The presence of an intratympanic tumor (eg, globus tympanicum, facial neuroma, meningioma) Vascular anomalies (eg, the internal carotid artery passing through the middle ear cavity) Blood dyscrasias or anticoagulation An incompletely or poorly visualized tympanic membrane An uncooperative patient[2]

Anesthesia

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Tympanocentesis can be performed under general or local anesthesia. Some patients, such as those with an acutely infected and painful otitis media, may not need anesthesia.

The use of local anesthesia is favored in a cooperative patient because of its safety, faster recovery, earlier discharge from hospital, reduced costs, reduced bleeding (when combined with a vasoconstrictor), and the ability to perform the procedure in the outpatient clinic.

The tympanic membrane can be effectively anesthetized by either field infiltration or the application of topical anesthetics. Both methods require consent from the patient or caregiver. For more information, see Topical Anesthesia and Infiltrative Administration of Local Anesthetic Agents.

Infiltration typically involves injection of a local anesthetic agent (eg, lidocaine and prilocaine), circumferentially into the subcutaneous layer of the distal external auditory canal.

o It provides effective anesthesia and, if combined with a vasoconstrictor, it can reduce intraoperative bleeding.

o The disadvantages are that the injection into the subcutaneous layer of the external auditory canal skin is rather painful; this technique, therefore, requires good cooperation from patients. It can also lead to bleeding, reducing visibility of the tympanic membrane.[3]

Topical anesthesia is preferred method for minor otological procedures, including tympanocentesis. It refers to the direct application of traditional local anesthetic agents such as lidocaine, cocaine, and phenol as well as newer techniques, such as iontophoresis and eutectic mixture of local anesthetics (EMLA).

o EMLA cream has been shown to be as effective as all other techniques. It takes 30 minutes to work but is easily administered inside the external auditory canal and is painless.[4]

o In all topical applications, the middle ear mucosa may continue to be sensitive; hence, the procedure is not a painless one.

Iontophoresis is a noninvasive method that uses direct current to propel a high concentration of charged anesthetic molecules across the tympanic membrane.

o Anesthetic solution, such as 4% lidocaine, is inserted in the external auditory canal and current of 0.5 nA is administered for 10 minutes via a negative electrode.

o This technique allows good anesthesia of tympanic membrane but not of the external auditory canal.[4]

Oral medication for pain relief during tympanocentesis was studied and it was suggested that acetaminophen alone was not as effective as acetaminophen plus codeine or ibuprofen plus midazolam.[5]

Equipment Microscope Appropriate chair and treatment couch Ear specula of various sizes Jobson Horne probe Wax hook Suction system/tubing with aural sucker attachment Topical anesthetic agent Spinal needle, 21 gauge (ga) Aspirating syringe, 3 mL Culture swabs and media Aural syringe, dental syringe and needle, pledgets, iontophoresis devices, and electrodes may be required.

Positioning Position the patient supine, with the head rotated away from the operator, to allow visualization of the

tympanic membrane using an appropriately sized aural speculum. Prior to the start of the procedure, remove any wax that may obscure the view.[2]

Technique Obtain informed consent. Position the patient as described above. Clear the external ear canal of any wax that might obscure the view. Administer a local anesthetic agent in one of the methods described above in Anesthesia. Connect the spinal needle to the 3-mL syringe, and bend the needle close to the attachment by about 45

degrees to allow easier visualization past the needle when it is in the external ear canal. Ensure that the syringe plunger is mobile and aspirate 1 mL of air. Optimal visualization is of prime importance. Take care to use the largest aural speculum that fits the

external ear canal, and do not proceed beyond the hair-bearing skin. Use a low magnification on the operating microscope to ensure orientation, and clearly identify the handle of the malleus and the inferior half of the tympanic membrane. Then increase the magnification of the microscope to allow precise placement of the needle.

Carefully advance the needle to the tympanic membrane, taking care not to damage the ear canal skin.

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Once on the tympanic membrane, advance the needle through it and aspirate the syringe (see image below). In children with acute otitis media, the perforation of the tympanic membrane is done quickly; in those with topical or no analgesia, the advance is often best done slowly to minimize the pain of passing

through the sensitive middle ear mucosa.[1] Illustration showing tympanocentesis with a needle in the lower half of the tympanic membrane.

In cases where injection into the middle ear space is the aim, create another perforation to help relieve pressure by letting air escape while fluid is injected (the so-called "blow-hole").

In laser tympanocentesis, a special adapter on the CO2 laser holds a mirror that is spun to create a small circular pattern. When fired, the laser instantaneously creates a small perforation, alleviating pressure from acute otitis media. Standard laser precautions must be observed.

Pearls Asking a patient to do a modified Valsalva maneuver (pinch nose and blow up cheeks) elevates some

tympanic membranes off the medial wall of the middle ear. This alleviates the need for a tympanocentesis to see if the tympanic membrane is fixed to the medial wall.

Some patients may well tolerate the procedure without anesthesia, if a small sharp needle is gently used in a rotary fashion to create a small opening.

Creating a so-called blow-hole (a second opening on the tympanic membrane) allows air to escape during injection of medication and prevents pressure building up in the middle ear cleft.

Complications Even with topical anesthesia, the medial surface of the tympanic membrane may still be sensitive, and

some amount of pain is likely during the procedure. A small amount of bleeding may occur, but it should stop spontaneously and should not be a reason for

concern. The tympanic membrane should heal spontaneously over the following few days to weeks, but a small risk

of a permanent perforation does exist.[6] In the short term, this may well be beneficial, as it may alleviate pain during future episodes of acute otitis media. In the long term, recurring infections due to water entering the middle ear space may necessitate a myringoplasty to close the perforation.

Although damage to middle ear structures, including the ossicles and facial nerve, is possible, it should not occur with a carefully performed procedure.

Diagnostic AccuracyPichichero and Poole studied the diagnostic accuracy of pediatricians and otolaryngologists as well as their tympanocentesis skills at a conference.[7] Overall, 50% of pediatricians and 73% of otolaryngologists correctly diagnosed the condition (acute otitis media vs otitis media with effusion), while 83% of pediatricians and 89% of otolaryngologists optimally performed tympanocentesis. This highlights the fact that acute otitis media and otitis media with effusion may often be misdiagnosed. Tympanocentesis is a useful adjunct in these conditions, helping with both diagnosis and treatment.