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Now rare postinfectious syndrome caused by the
extension of a middle ear infection to the petrous apex with abducens palsy.
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Gradenigo Petrosum Syndrome; Gradenigo Triad;
Gradenigo-Lannois Syndrome; Abducens Nerve Palsy-Petrous Osteomyelitis
Syndrome; Petrous Osteomyelitis-Abducens Nerve Palsy Syndrome.
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Guiseppe Conte Gradenigo, an Italian Otolaryngologist
(1859-1926), described this syndrome in 1904.
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Incidence has widely decreased since the development of
antibiotics.
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Caused by extension of an infection of the middle ear,
mastoid sinus, or both to the petrous apex that occurs because of extensive
pneumatization and the presence of bone marrow. The proximity of
the venous sinuses to the petrous apex is the reason for the historically
high incidence of venous sinus thrombosis associated with petrous apicitis.
Petrous apicitis is believed to result when organisms, typically
pseudomonas, become trapped within the complex air cell system of the
petrous apex. Blockage of this air cell system may result from acute or
chronic inflammation or from mechanical blockage by an obstructing lesion. The
inflammation may extend into the Dorello canal, which contains cranial
nerve (CN) VI and the Gasserian ganglion (CN V). Inflammation of the canal
produces the triad of symptoms recognized by Gradenigo: lateral rectus (CN
VI) palsy, retroorbital pain, and otorrhea.
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Based on the clinical findings of a coexisting
ear infection and ipsilateral paralysis of the abducens nerve and otorrhea.
Severe pain in the area supplied by the ophthalmic branch of the trigeminal
nerve is generally associated. The MRI can show focal enhancement of the
meninges over the petrous apex and extension of the infection into Meckel
cave (the cavity that harbors the trigeminal ganglion).
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Pain is typically severe, centered within the
ear, burning or throbbing, worse at night, aggravated by jaw movement, pressure over the
tragus, and traction upon the auricle. Pain can be observed simultaneously
in the frontal and parietal regions. In the largest series of patients with
petrous apicitis, the most common presenting symptoms were hearing loss in
60% of patients, deep pain (50%), CN VIII involvement (50%), CN VI
involvement and meningitis (25%), facial paralysis (25%), CN IX palsy
(15%), and CN X palsy (15%). Other features include excessive
lacrimation, fever, and reduced corneal sensitivity. Extension of the
inflammatory process can involve palsy of CN II through X, Horner syndrome.
Thrombosis of the venous sinuses, hemorrhage of the carotid artery, and
meningoencephalitis are the most serious complications. Before the introduction
of antibiotics, mortality rate was greater than 50%.
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Evaluate neurologic function and
review history (clinical, history, CT, MRI).
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Avoid all intranasal probes because of
infection. Since jaw movement may exacerbate pain, mouth opening may be limited
in the awake state, but is expected to normalize once anesthesia has been
induced.
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Avoid nitrous oxide
because of its effect on pneumatized spaces that may result in increased pain.