Gradenigo syndrome

Gradenigo syndrome consists of the triad of:

• suppurative otitis media with persistent otorrheaotorrhoea and ear pain
• abducens nerve palsy, secondary to involvement of the nerve as it passes through Dorello canal
• retro-orbital pain, or pain in the cutaneous distribution of the frontal and maxillary divisions of the trigeminal nerve, due to extension of inflammation into Meckel cave

Additionally patients tend to suffer intractable otorrhoea and pain in the region of the ophthalmic and maxillary branches of the trigeminal nerve.

Epidemiology

The incidence of this condition has significantly diminished since the antibiotic era, however, it is still occasionally observed, and often diagnosed late due to the subtlety of the symptoms ⁴.

Clinical presentation

The classic constellation of symptoms is described above, however, it is important to note that not all patients will present with the complete triad. In addition, other symptoms may include:

• involvement of the facial nerve and vestibulocochlear nerve ⁵
• photophobia
• fever
• excessive lacrimation

Further spread of infection may give rise to complications, including:

• intracranial abscess
• meningitis
• skull base involvement
• parapharyngeal abscess
• prevertebral abscess

Pathology

The syndrome typically arises as a consequence of chronic suppurative otitis media spreading to the petrous apex of the temporal bone, resulting in petrous apicitis. The trigeminal ganglion and abducens nerve lie in close proximity to the petrous apex, within Meckel cave and the Dorello canal respectively. Extradural inflammation due to petrous apicitis may therefore affect these nearby structures and give rise to the classical symptoms of Gradenigo syndrome ⁴. Common pathogens are Pseudomonas and Enterococcus spp. 

Radiographic features

CT

Findings may include bone destruction, opacification of the petromastoid air cells, and intracranial abscess formation ⁴.

MRI

MRI can aid differentiation between neoplasia and infection, as well as being superior to CT in demonstrating the inflammatory changes of petrous apicitis ⁵.  

Treatment and prognosis

The mainstay of treatment is antibiotic therapy ⁴. Rare cases may require surgical intervention.

History and etymology

ItGradenigo syndrome was first described in 1907 by Giuseppe Conte Gradenigo (1859-1926), an Italian otolaryngologist ^2,3.