Semay Baydar

Introduction

Gradenigo syndrome is a rare but important complication of otitis media. It is classically described as a triad of persistent ear infection, abducens nerve (cranial nerve VI) palsy, and retro-orbital or facial pain along the trigeminal nerve (cranial nerve V) distribution. From an ophthalmologist’s perspective, the lateral rectus weakness and resulting diplopia are often the first symptoms that prompt referral. The syndrome arises when infection spreads to the petrous apex of the temporal bone, leading to osteomyelitis and subsequent cranial nerve dysfunction (1,2).

Ophthalmic Presentation

Patients typically present with horizontal diplopia due to lateral rectus weakness, sometimes accompanied by eye pain or discomfort behind the orbit. Retro-orbital pain or facial pain may also be reported. While the full triad is not always present, recognition of cranial nerve VI involvement in the context of recent or chronic otitis media is crucial. Documenting the degree of ocular motility restriction, associated diplopia, and any compensatory head posture helps guide ongoing management and monitors recovery over time.

Aetiology and Pathophysiology

Gradenigo syndrome most commonly develops following acute or chronic otitis media, though cholesteatoma and previous ear surgery can also predispose to petrous apex involvement. The usual bacterial culprits include Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus species (3). The abducens nerve is particularly susceptible due to its long course along the petrous apex, explaining why diplopia is such a prominent feature.

Investigations

Early imaging is essential. CT of the temporal bone can identify bony destruction, while MRI provides a clearer view of soft tissue, petrous apex osteomyelitis, and cranial nerve involvement. Extraocular movements shold be documented along with assessment of diplopia, and visual function. Blood tests and cultures are supportive, guiding antibiotic choice but rarely providing a definitive diagnosis (2,4).

Management

Management is multidisciplinary. Intravenous broad-spectrum antibiotics targeting common pathogens form the cornerstone of treatment, usually for four to six weeks. Surgery is reserved for cases with abscess formation, cholesteatoma, or poor response to medical therapy and may include mastoidectomy or petrous apex drainage. Ophthalmology’s role here is monitoring cranial nerve recovery and diplopia, as early recognition of persistent deficits can guide rehabilitation and follow-up (2,4).

Prognosis

With prompt treatment, outcomes are generally good. Most patients experience full recovery of eye movement, although delayed diagnosis increases the risk of permanent cranial nerve deficits. Early recognition, multidisciplinary management, and careful ophthalmic monitoring are essential to ensure the best outcome.

References

1. Gradenigo G. Le syndrome apical de la pyramide pétreuse. Rev Neurol (Paris). 1907;15:321–37.
2. Sweeney AD, Garcia J. Gradenigo syndrome: a case report and review of the literature. Int J Pediatr Otorhinolaryngol. 2001;61(3):257–61.
3. Youssef H, El Beltagy H, Aly H. Gradenigo syndrome: clinical features and management strategies. Otol Neurotol. 2017;38(8):1102–7.
4. Ibrahim M, Shah G, Parmar H. Diffusion‑weighted MRI identifies petrous apex abscess in Gradenigo syndrome. J Neuroophthalmol. 2010 Mar;30(1):34–36. doi:10.1097/WNO.0b013e3181c5d0fd. PMID: 20182204.