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COMPLICATIONS OF TEMPORAL BONE

INFECTIONS

Chapter 134 

Lee A. Harker   Clough Shelton

GENERAL CONSIDERATIONS

• > in children/ in the first two decades of life.• postauricular abscess, <6 years.• in Turkey, 58%,<20 years.• males \females=2• More that who:• are poor and live in overcrowded surroundings, have poor personal

hygiene, poor health, decreased resistance to infection, inadequate health education, and limited access to medical care

• large series of patients with complications of otitis media have not been reported in patients with HIV infection or AIDS or in those receiving immunosuppressive therapy after organ transplantation, even though such individuals do have suppurative ear disease.

Acute Otitis Media • most common bacterial infection of childhood• Predisposing factors:1- young age 2- male sex, 3-receiving bottle

feedings, 3-exposed to a day care environment, crowded living conditions,4- or smoking within the home.

• Medical conditions such as cleft palate, Down syndrome, and mucous membrane abnormalities such as cystic fibrosis, ciliary dyskinesia, and immunodeficiency states also predispose persons to otitis media.

• Tympanocentesis ----for culture &----------------reduce the bacterial population.

• After treatment,-----document that the AOM has completely resolved---- by tympanometry and otoscopy

• . If the complication was intracranial, ------(CT) scan or a (MRI) should be obtained

Chronic Otitis Media • COM =infectious process persists for longer than the 1 to 3w usually

necessary for resolving AOM• If infection does not resolve-- mucosal edema and

exudation ,mucous glands proliferate. --antrum block between the middle ear and the epitympanum and in the aditus between the epitympanum and mastoid the normal pathways for aeration and decrease both oxygenation and vascularity.

• bacteriology of COM: cultures of 30 cholesteatomas isolated at least one anaerobic :in 67%, at least one aerobic 70%, and both aerobes and anaerobes in 50%. In 57% multiple /in 30% five or more bacteria

• COM in patients with VT different bacterial .treatment with antibiotic drops OR oral antibiotics,^ fungal overgrowth &&resistant organisms developing.

• The resistant bacteria most often found are Pseudomonas aeruginosa, Achromobacter xylosoxidans, and even methicillin-resistant Staphylococcus aureus.

PATHOPHYSIOLOGY

• complication from AOMresult from bacteremia ( hematogenous:like meningitis. Or by access to adjacent or distant structures.

• develop facial paralysis if congenital dehiscence of the bony fallopian canal above the stapes

• If pathways leading to the meninges or the labyrinth, at risk to develop meningitis, subdural effusion, or suppurative labyrinthitis( Developmental labyrinthine abnormalities like enlarged vestibular aqueducts or the Mondini )

• In older children and adults, :pathways left from previous surgery or temporal bone fractures.

PATHOPHYSIOLOGY

• In AOM complications develop by hematogenous dissemination or by direct extension of infection along preformed pathways.

• AOM: medical treatment, and mastoidectomy is not necessary.

• In COM and mastoiditis, complications are always associated with :

• 1-bone destruction, • 2-granulation tissue formation,• 3-or the presence of cholesteatoma

DIAGNOSIS

• HX(when free, last examine the involved ear , past history and treatment of the patient's otitis ,

• symptom of AOM: pain, fever, and fussiness not otorrhea• symptom of COM: painless purulent drainage• The cessation of drainage with the onset of pain

suggests the presence of aditus or epitympanic block with increased pressure within the mastoid.

• imbalance or vertigo possibility of imminent labyrinthitis.

• by chronology of this alteration of sensorium differentiate among brain abscess, meningitis, and subdural empyema.

• A brain abscess takes weeks to develop,• several days for meningitis • subdural empyema to become fulminant and progress to coma.

Physical Examination • The vital signs, especially T&temperature curve • A complete neurologic examination (mental assessment , gait

and perform the Romberg and sharpened Romberg tests. motor and sensory function ,complete cranial nerve evaluation, nystagmus , nuchal rigidity ,Kernig's and Brudzinski's tests , optic discs )

• The otologic examination (pinna , The external auditory cana and tympanic membrane By using a microscope and fine suction, Pneumatic otoscopy for conjugate deviation of the eyes - presence of a labyrinthine fistula )

• The TM :can normal or near normal even complication • With TX in ME&Mastoid : middle ear may revert to normal

while the mastoid may not.( Especially in aditus block)• . with any infectious condition that could be caused by acute

or chronic otitis, CT to R/O COM as the cause, even TM be normal

PARACLINIC• LAB (CBC,Hb--for GA)• Imaging (CT scan : • status of the middle ear and the mastoid air cell system,• bony details of the middle ear, epitympanic, and mastoid structures,• erosion of the bony plates covering the sigmoid sinus, cerebellum,

or tegmen of the middle ear and mastoid,• establish the specific primary otologic diagnosis (e.g., AOM, COM,

cholesteatoma) • assessing the results of therapy and provide a baseline

posttreatment study • MRI is a far more sensitive imaging technique than CT scanning for

diagnosing intracranial complications• T2W-->intraparenchymal edema from subtle brain infection much

earlier than can a CT scan • CT&MRI: complimentary

TREATMENT

• AOM: antibiotic therapy+tympanocentesis or myringotomy. NO surgery

• complications resulte from COM and mastoiditis, broad-spectrum antibiotics (against anaerobic And aerobic )+ mastoidectomy

• in intracranial complications, the neurosurgeon operates first, immediately followed by the otologist

• Postoperative follow-up :. Even when the patient responded perfectly, follow-up CT scan to objectively confirm the status of the mastoid because there is a risk of recurrence or emergence of new intracranial complications

• In lateral sinus thrombosis, epidural abscess, subdural empyema, or brain abscess, follow-up evaluation with enhanced MRI 2 to 4 weeks after treatment

Extracranial (Intratemporal) Complications

• 1-Acute Mastoiditis • 2-Coalescent Mastoiditis • 3-Chronic Mastoiditis • 4-Masked Mastoiditis • 5-Postauricular Abscess • 6-Bezold Abscess • 7-Temporal Root Abscess • 8-Petrous Apicitis • 9-Labyrinthine Fistula • 10-Facial Nerve Paralysis • 11-Acute Suppurative Labyrinthitis • 12-Encephalocele and CSF Leakage

Acute Mastoiditis

• when AOM fails to resolve • signs of AOM and local inflammatory findings over the

mastoid proc • 28% < 1 year, 38% 1 - 4 years, 21% 4 -8,M:16m• TM perforation: in <1/4; TM bulging or erythematous in

two-thirds • 22% : complications on admission, the most common

of which was subperiosteal abscess • average duration from the onset of disease (AOM) until

admission for acute mastoiditis was 9 days. • Only 1/3 :asymptomatic interval between their AOM

symptoms and the mastoiditis.

Coalescent Mastoiditis • AOM and mastoiditis that persist unabated for 2 to 4

weeks, coalescent mastoiditis develops.• disease of the young, especially of boys.<4y• Bacterial virulence and decreased host resistance are

important in its etiology, but mastoid development also plays a role

• changes in the bone and mucoperiosteum of the mastoid air cell system.(decalcifies the bony partitions, causing the small air cells to coalesce into a larger cavity .

• intense inflammation and infectionphlebitis and periphlebitis Extend to adjacent meninges, sigmoid sinus, cerebellum, and the temporal

• The most common pathway for infection to extend beyond the mastoid is through the lateral cortex behind the ear.

Coalescent Mastoiditis• SYM:purulent otorrhea, fever, toxicity, and

ear pain.same AOM but more tox&T• hX :chronology :purulent drainage or

significant otalgia persists >2W• SIGN:mastoid tenderness, erythema, and

sagging of the posterior superior EAC IMAG:CT/intracranial complication :MRITx:can be either medical or surgical ( without

surgery AB3-6W(SUR+-? high risk)=complete

mastoidectomy with VT end of medTX, IMAG (for doc)

Chronic Mastoiditis

• 1)with a longstanding TM perforation, 2)with cholesteatoma,3) or as a complication from an infection after placement of a middle ear VT

• central perforation infected mastoid(chronically drain). Even though uninfected cholesteatoma for long periods of time, it tends to suppurate, form granulation tissue, and erode bone.

• purulent drainage> 8 W, the likelihood of a complete resolution with antibiotics

• Chronic mastoiditis requires surgical intervention to heal, and an infected cholesteatoma requires surgical ablation, regardless of duration

Masked Mastoiditis

• granulation tissue formation and bone erosion can occur without otorrhea

• received numerous courses of antibiotics • normal or near normal TM • Age:M:13Y• chronic but not severe auricular and

postauricular pain, tenderness to mastoid • CT : localized opacification• Tx:surgical (regardless of the appearance of the

TM)

Postauricular Abscess

• most common complication of mastoiditis • accompanying acute or coalescent mastoiditis in

young children • mastoid near the spine of Henle exist in newborns as

a series of open channels between the interior of the mastoid and the cortex

• direct extension subsequent to bone destruction • process in that upper portion and the tissue edema

and the abscess drive the auricle downward and laterally

• TX:excision and drainage + mastoidectomy

Bezold Abscess

• perforation in the bony platePus burrows downward in the neck beneath the sternomastoid, or may be confined between layers of the deep cervical fascia

• >in older children in( pneumatization has extended into the mastoid tip)

• Dx:deep, tender, upper cervical massesmiss• Tx:1 -excision of the mastoid pathology• 2-drainage of the abscess, • 3-removal of granulation tissue

Temporal Root Abscess

• infection of soft tissues sup. and ant. auricle can abscess involves the cells of the zygomatic root of the mastoid (temporal root of the zygoma )

• 1)direct extension via bone erosion through the epitympanic temporal root cells 2)or phlebitis and periphlebitis.

• The clinical picture is very confusing because abscesses in that location are rare.

• CT :to R/o mastoiditis as the source. • TX:SURGERY

Petrous Apicitis

• . Pneumatization in only 30% of PETROS.Rare/• pathology :mirror of coalescent mastoiditis, or

granulation tissue with chronic mastoiditis. Cholesteatoma Rarely,

• Dx:CT(bone)&MRI(BM)• SYM 1- retroorbital pain (irritation of the Vganglion

in Meckel's cave)• , 2- paralysis of the VI ( passes through Dorello's

canal )• 3-or dysfunction CNs VII and VIII• (Gradenigo's syndrome ):retroorbital pain, sixth

nerve paralysis, and otorrhea• TX:prolonged AB+-Surgery(if obvious necrotic bone )

Labyrinthine Fistula

• erosive loss of the endochondral bone overlying the semicircular canals without loss of perilymph( without loss of perilymph)

• majority :involve only the lateral semicircular canal./secondary to cholesteatoma, in 7% of the cholesteatomas

• The mechanisms:demineralization of the dense endochondral bone(at surgery as a "blue line" parallel to the underlying semicircular canal)

• coexisting complications:. 1- facial nerve dysfunction in 60%/ 2-dehiscences of the tegmen occurred in 39%

Labyrinthine Fistula • Symptoms : vestibular. imbalance, dysequilibrium, or vertigo

but have normal equilibrium most of the time• momentary imbalance by pushing on their external ear canal&

(Tullio's phenomenon).• Sign :fistula test =positive pressure conjugate deviation of

the eyes away from the side of compression(only 55% to 70% of patients)

• Tx:surgical for underlying cholesteatoma:mastoidectomy /in a canal-wall-up technique is made on the basis of the surgeon's ability+

• Repair:1)microsuction elevates the cholesteatoma 2) the endosteum is torn3)a small piece of tissue or a shaped cap of bone is placed over the site and secured in place with fibrin glue or packing

• large fistulas, :canal-wall-down procedure and leave the fistula covered by matrix, which later forms the mastoid cavity lining.

•

• Fistula of the right lateral semicircular canal (arrow) seen on axial temporal bone CT.  

Facial Nerve Paralysis

• result from AOM, COM without cholesteatoma, or cholesteatoma.

• edema pressure and inflammation avascular necrosis & suppurative neuritis destroys the neural elements.

• AOM:In young children, incomplete :only in infants with congenital dehiscence of the fallopian canal ,<3w

• Facial nerve paralysis :by cholesteatomainvolve the nerve in the middle

• COM without cholesteatoma:horizontal portion of the facial nerve near the stapes

• TX:IN AOM:AB+-myringotomy • IN COM: surgical decompression of the facial nerve

» Coronal CT scan showing epitympanic mass (arrowheads) involving facial nerve geniculate ganglion area (arrow) causing facial paralysis in a case of chronic otitis media.  

Acute Suppurative Labyrinthitis• Bacterial invasion of the labyrinth total loss of both auditory and

vestibular function

• ETIOLOGY:1)congenital labyrinthine deformities such as Mondini deformity and enlarged vestibular aqueducts2) through a cholesteatomatous lateral semicircular canal fistula is another

• DX:Clinical: tinnitus and vertigo, pallor, diaphoresis, nausea, and vomiting. The vestibular symptoms :max for 8 to 12 h, even if s totally immobile and IV AB

• Brisk labyrinthine nystagmus directed toward the opposite ear

• next 2or3W CNS adaptationnormal or near normal balance

• No specific diagnostic studies are necessary when the typical clinical picture develops

• IV AB for 10D to prevent propagation to the meninges(NO REVERS CLIN.COURSE

• labyrinthectomy is not necessary in labyrinthitis secondary to AOM.

Encephalocele and CSF Leakage

• CSF leakage due to :defects in the tegmen tympani or, less commonly, the tegmen mastoideum./80% > 45 y

• Etiology:1)cholesteatoma and granulation tissue(80%): erode bony plates between mastoid and temporal lobe, the cerebellum, and the dura 2)truma or previuse surgery

• Symp:1) hearing loss ( reduced ossicular motion from the middle ear fluid or the encephalocele )2) signs and symptoms of meningitis,

• TX:surgical repair. Depend to size • The middle fossa approach provides excellent exposure

of the tegmen defect and access to repair the dural defect • temporalis fascia graft dura.& calvarial bone graft

taken from the inner table of the craniotomy flap- The bony defect

Intracranial Complications Meningitis

• immunizations H. influenzaemeningitis dramatically decreased/<2y/AOM:hematogen

• RF:1) longitudinal temporal bone fractures. 2)Congenital defects of the tegmen 3)unrecognized injury to the dura of the posterior or middle cranial fossae during mastoid surgery.4) Patients with syndromic or nonsyndromic congenital stapes fixation, Mondini dysplasia, and enlarged vestibular aqueducts

• Sym:1)generalized severe headache. /2)tends to lie quietly, /3)photophobia 4) general hyperesthesia,5) vomits. Chang level of consciousness from normal, to coma 6)Fever

• Sign:Nuchal rigidity 2) pain with attempted flexion of the neck 3)abnormal abdominal reflexes. 4) Brudzinski's sign, 5) Kernig's sign,

Meningitis• Paraclinic:meningitis is suspectedCT scanR/O

abscess&safe LP• CSF from the LP :for pressure, cells, bacteria, glucose,

protein, chloride, and other factors • TX:IN AOM:AB+Myringotomy (no surgery)• from COM and mastoiditis: AB+mastoidectomy • In profound ipsilateral SNHL route of infection : the

labyrinth.If the sensorineural function in the affected ear remains at the patient's premeningitis baseline, the route was extralabyrinthine

• enhanced MRI should be obtained to rule out the presence of any additional intracranial complications

• mastoidectomy should be performed as soon as the patient is stable

Brain Abscess • 3th etiology after CHD&truma • Abscesses from AOM and COM were almost always found on

the same side as the otitis / in the temporal lobe and cerebellum.• 3/4 secondary to cholesteatoma, 50% occurred in the second

decade of life, 2/3M• arrival of bacteria into the cortex migration of polymorphs

into local capillaries focal cerebritis( managed by IV AB) hemorrhagic, and necrotic, and the abscess is formed.

• SYM:sepsis, cerebellar abscess : coarse horizontal nystagmus, dysmetria, dysdiadokokinesia, or action tremor. Temporal lobe abscess : homonymous visual field defects, contralateral hemiparesis

• DX:MRI• TX:broad-spectrum IV AB( directed at aerobic and anaerobic ).

patient's condition is stable, neurosurgical drainage or abscess excision is performed within the first 24 hours of admission and is followed immediately by mastoidectomy,

Subdural Empyema • fulminating purulent infection that develops between the dura

and the pia arachnoid • otologic etiology is uncommon • 2/3 M, in the second decade of life.• infection enters the subdural space, pus forms rapidly.

thrombophlebitis of cortical veins raised ICP, focal signs, and seizures

• SYM:severe headache?( earliest & persistent) T rises dramatically /General malaise, chills, and nuchal rigidity. Change level of consciousness focal signs

• left-sided collectionsaphasia & contralateral hemiparesis • Sign:Paralysis of conjugate gaze , Jacksonian seizures

papilledema • In posterior fossa collections, localizing signs are often absent,

but marked neck stiffness and papilledema are always present • DX:contrast CT(In early NLMRI)• TX:Emergency neurosurgical drainage & AB therapy

Epidural Abscess • cholesteatoma, G.Tbone erosion inflammatory

responseabscess between the temporal bone and the underlying dura mater pachymeningitis

• sym:deep mastoid pain, but some without sym. only at surgery • DX:CT –contrast/MRI• TX:Surgery(I&D)+Mastoidectomy • exenterate the air cells, proceeding from lateral to medial and from

regions of less disease to those with more disease. • posterior aspect of the bony EAC; the tip cells should be removed.

This will maximize exposure and hemostasis • dura is thickened by the infection, blunt flat instruments such as a

Freer elevator or large curettes can safely scrape the granulation tissue from the abscess cavity and identify the most centripetal extent of the abscess.

• using diamond burrs, rongeurs, or curettes until healthy dura without granulation tissue is evident on all margins of the abscess

Lateral Sinus Thrombosis • cholesteatoma, GT bone erosion perisinus abscess

pressure on the dural outer wall of the sinus necrosismural thrombusinfected, enlarges thrombus extend in a retrograde direction to the transverse sinus &the torcular Herophili, and even to the superior sagittal sinus

IVG(to neck)&cavernous.• Infection of.septicemia and the possibility of metastatic

abscesses (most commonly to the lungs.• most common in adults or older children with cholesteatoma • Mix complication (meningitis, epidural abscess, subdural empyema,

cerebritis, or cerebellar abscess)obscure the clinical picture • signs and symptoms: septicemia or blockage of blood flow through

the sinus\The picket-fence fever pattern /neck pain &stiffnesspain and tenderness along the anterior border of the SCM\tenderness of the mastoid tip

• sudden intracranial hypertension resulting from decreased venous drainage

• Most prominent is the occurrence or sudden worsening of a severe headache.

Lateral Sinus Thrombosis• DX:imaging:both CT(contrast)&MRI• delta sign seen on the CT scan(enhancement of the wall of the

sigmoid sinus )• TX:all mastoidectomy+management of the infected clot and sinus

wall (time:controversy)if abscess:I&D befor mastoidectomy / in+meningitis if stable

• Management of the clot : anticoagulation(not routin BUT IN extension of the clot to the transverse sinus or cavernous sinus )+ligation of the jugular vein in the neck(if extension to neck)+ and opening the sinus and evacuating the infected clot +neurosurgical decompression and steroids

• Intravenous thrombolytics are not routinely used in the presence of the infected vessel wall.

• The sinus: only after the mastoidectomy • a reported from mastoidectomy without opening and evacuating

the lateral sinus clot. All patients survived, but long hospitalization

Otitic Hydrocephalus

• Block venous drainage after sudden interruption of a portion of the venous drainage system near one ear acute hydrocephalusICP rises brain edema

• a diffuse severe headache with (or occasionally without) medical management, the continuous headache gradually ameliorates and dissipates over 3 to 7 days

• If no adequate collateraldulling of the sensorium or decreased visual acuity from retinal vein occlusion appearcoma and death

• DX:CT scanning• MANAG: immediate neurologic and neurosurgical

consultation