38 Complications of Otitis Media Flashcards
Describe the pathophysiology of complications related to acute otitis media (AOM).
Describe the pathophysiology of complications related to acute otitis media (AOM).
The pathophysiology of complicated otitis media (OM) largely depends on whether it arises in the setting of AOM or chronic suppurative otitis media (CSOM). AOM develops in previously healthy ears and is characterized by mucosal edema with exudation of fluid, bacterial proliferation, and the formation of byproducts of inflammation (pus). Infection then spreads contiguously into the mastoid. Given the lack of granulation tissue and bony erosion with AOM, infection spreads either hematogenously or through direct extension via preformed pathways.
Describe the pathophysiology of complications related to chronic suppurative otitis media (CSOM).
Describe the pathophysiology of complications related to chronic suppurative otitis media (CSOM).
CSOM is characterized by persistent mastoid and middle ear inflammation and infection. This can occur with or without cholesteatoma, tympanic membrane perforation, or persistent otorrhea through ventilation tubes. When infection and inflammation persist, mucosal edema blocks off the normal pathways for drainage and aeration between the mastoid and middle ear. Continued inflammation results in bony destruction and granulation tissue formation. Infection subsequently spreads through direct extension via bony erosion from cholesteatoma or osteitis, or possibly through preformed pathways (more commonly associated with AOM).
What are some examples of preformed pathways?
What are some examples of preformed pathways?
Examples of preformed pathways are congenital inner ear anomalies such as Mondini’s malformation or an enlarged vestibular aqueduct, trauma from previous surgery, or prior temporal bone fractures. These pathways increase the risk of direct extension of infection in the middle ear and mastoid.
What are the three pathways that result in complicated OM?
What are the three pathways that result in complicated OM?
The three main pathways that result in OM complications are hematogenous spread, direct extension though bony erosion or preformed pathways, and thrombophlebitis of local perforating (diploic) veins.
What is an example of hematogenous spread of infection with OM?
What is an example of hematogenous spread of infection with OM?
Meningitis is an example of hematogenous spread. Meningitis usually occurs as a result of AOM rather than CSOM, and classic symptoms include headache, nausea, nuchal rigidity, photophobia, altered mental status, and fever. Cerebrospinal fluid examination is critical, and many times computed tomography (CT) is performed to rule out other intracranial complications and mass lesions.
What are examples of direct extension?
What are examples of direct extension?
Direct extension results in a variety of complications depending upon the area of spread. Complications such as postauricular abscess, Bezold’s abscess, sigmoid sinus thrombosis, epidural abscess, and subdural empyema all result from direct extension (see Figure 38-1, demonstrating a postauricular abscess on CT w/ contrast).
What is a Bezold’s abscess?
What is a Bezold’s abscess?
A Bezold abscess is a complication of acute otomastoiditis where the infection erodes through the mastoid cortex medial to the attachment of sternocleidomastoid, at the attachment site of the posterior belly of the digastric muscle, and extends into the infratemporal fossa. Due to it being deep to the cervical fascia that envelops the sternocleidomastoid muscle and trapezius muscle, it is difficult to palpate.
What is the bacteriology of complicated OM?
What is the bacteriology of complicated OM?
Complicated otitis media characteristically has an increase in resistant organisms, and is often polymicrobial. Frequently cultured organisms include P. aeruginosa, S. aureus including methicillin resistant strains, K. pneumoniae, P. acnes, and Bacteroides species.
What is the epidemiology of complications associated with OM?
What is the epidemiology of complications associated with OM?
The majority of complications associated with OM occur in children and young adults. Incidence varies among studies, but 60% to 80% of complications occur in the first two decades of life.
What is the most common complication of OM?
What is the most common complication of OM?
The most common complication of OM is otitis media with effusion (OME). This entity is defined as middle ear effusion without signs of acute infection or inflammation, and may contribute to hearing loss.
What is the classification schema for complications of OM?
What is the classification schema for complications of OM?
Complications can be divided into intracranial or extracranial/intratemporal (Table 38-1).
What are important presenting symptoms for complications of OM?
What are important presenting symptoms for complications of OM?
The signs and symptoms of OM and its associated complications can be quite broad, depending on the structures affected. Symptoms typically will begin with otalgia, irritability, and fever in AOM. CSOM may be initially more subtle, presenting with persistent purulent otorrhea. Patients may have postauricular pain, edema, otorrhea, and erythema with mastoid infection or abscess. Additionally, a patient’s level of consciousness may be altered from intracranial complications. The time period of mental status change is variable based on the specific type of intracranial complication. The patient may exhibit papilledema, cranial nerve palsies, nuchal rigidity, or other neurologic findings.
What is the role of imaging in the diagnosis of complicated OM?
What is the role of imaging in the diagnosis of complicated OM?
A CT should be performed with contrast to assess for soft tissue and intracranial abscesses, inflammation, and flow voids in vessels. CT also allows evaluation of the osteology of the temporal bone specifically related to aeration of the middle ear and mastoid, bony dehiscence or erosions, and evaluation of cholesteatoma. However, it should be noted that imaging for OM is not needed unless there is worry about associated complications. Since the middle ear is connected to the mastoid air cell system, imaging of any acute OM likely will show mastoid opacification and thus may be interpreted as mastoiditis by the radiologist. Although CT offers excellent initial evaluation of suspected complications of OM and is much faster, MRI is more sensitive for diagnosis of intracranial complications. MRI detects subtle cerebral edema, dural enhancement, abscess, and vessel lumen patency more sensitively than CT. Both modalities are complementary to one another in diagnosis, management, and response to treatment. However, CT is a much quicker alternative than magnetic resonance imaging (MRI) in patients who are unstable or with altered mental status.
What are important physical exam findings in complicated OM?
What are important physical exam findings in complicated OM?
A complete head and neck examination as well as a neurologic exam should be completed if there is any suspicion of complications of OM. The otologic exam may reveal signs of acute infection such as an erythematous, bulging, and opaque tympanic membrane, or may show perforation with purulent otorrhea, granulation tissue, or signs of a cholesteatoma. Postauricular or temporal abscesses may exhibit pain with palpation, erythema, and fluctuance. Vestibular symptoms may be present in certain cases with periods of imbalance, dysequilibirum, and vertigo.
Intracranial complications may present with papilledema, abducens nerve palsy, nuchal rigidity, positive Kernig or Brudzinski’s signs, and altered mental status. Posterior superior sagging of the external auditory canal may be indicative of canal erosion from cholesteatoma. Facial nerve paralysis is not an uncommon finding, especially with bony dehiscence within the middle ear and resultant inflammation of the facial nerve. Petrous apicitis may present with abducens nerve palsy. It is therefore important to conduct a thorough cranial nerve examination.
What are some eponyms that your attending might quiz you on?
What are some eponyms that your attending might quiz you on?
- Queckenstedt’s sign is a test to determine whether cerebrospinal fluid (CSF) flow is obstructed in the subarachnoid space of the spinal canal by applying bilateral pressure on the internal jugular veins during lumbar puncture. No rise in pressure during this maneuver indicates obstruction of CSF flow as seen in meningitis or lateral sinus thrombophlebitis.
- Gradenigo syndrome is the triad of symptoms associated with petrous apicitis including retro-orbital pain, abducens nerve palsy, and otorrhea.
- Bezold’s abscess is a cervical infection on the medial side of the mastoid deep to the digastric ridge that develops into an abscess.
- Citelli abscess is a cervical infection extending along the posterior belly of the digastric muscle that develops into an abscess.