Gradenigo syndrome, also known as petrous apicitis or apical petrositis, is a rare complication of suppurative otitis media, with only a few cases reported (mostly in the otolaryngology literature). The syndrome is a triad of sixth nerve palsy, pain in the distribution of the trigeminal nerve, and otitis media. It was first described by Giuseppe Gradenigo in 1904; the incidence has since diminished with the advent of antibiotic use.
In his original description of the disease, only 42% of the cases he described exhibited the classical triad. The neurologic manifestations of Gradenigo syndrome are attributed to the involvement of the fifth and sixth nerves, which are only separated from the inflamed petrous bone apex by the dura matter. The temporal bone not only contains the organs for hearing, balance, and sound conduction, but it also contributes to the cranial vault and zygoma. The temporal bones are situated at the sides and base of the skull and consist of five parts: the squama, mastoid, petrous, tympanic, and styloid process. The petrous portion, called the petrous pyramid, contains the otic and labyrinth. Superiorly, it forms the inferior surface of the middle cranial fossa. Posteriorly, it is bounded by the attachment of the tentorium cerebelli, and together with the mastoid portion it helps to form the anterior face of the posterior cranial fossa. At the petrous apex, there is a hiatus between the tentorium and the petrous that forms a canal for the fifth cranial nerve (Meckel cave). The sixth cranial nerve runs through a notch just below the posterior clinoid process (the medial attachment of the tentorium) and above the articulation of the petrous and sphenoid (Dorello canal).
The inflammatory process spreads from the base (mastoid and middle ear) of the pyramid-shaped os petrosum to the top (petrous apex). This explains why the time interval between the onset of otitis media and the manifestation of cranial nerve dysfunction varies between 1 week and 2-3 months.
Complications of Gradenigo syndrome include the following:
Spread to the skull base and involvement of the ninth, tenth, and eleventh cranial nerves; known as Vernet syndrome
Spread to the sympathetic plexus around the carotid sheath
Venous sinus thrombosis
The differential diagnosis of Gradenigo syndrome includes tumors of the petrous apex, such as meningioma, sarcoma, trigeminal neuralgia, or metastatic disease. Gradenigo syndrome in children usually results from an infectious etiology. The organisms causing Gradenigo syndrome are often difficult to recover, and cultures from the middle ear and mastoid or petrous tissue may be negative; however, common organisms recovered include group A Streptococcus, pneumococcus, Staphylococcus, Pseudomonas aeruginosa, and Mycobacterium tuberculosis.
The evaluation of a patient with suspected Gradenigo syndrome should include neuroimaging. A reasonable initial imaging modality is a CT scan of the head with high resolution to provide detail of the petrous apex, as the test is widely available and can identify abnormalities in bony anatomy. MRI is superior, however, for demonstrating the CNS anatomy and meningeal enhancement, which makes it the ideal test to diagnose Gradenigo syndrome. MRA and/or MRV may be useful in evaluating sigmoid sinus pathology.
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Cite this: Olugbemiga Jegede, Walid Abuhammour. Double Vision and Ear Discharge in a 14-Year-Old Girl - Medscape - Dec 09, 2015.