Tolosa-Hunt syndrome is an idiopathic inflammatory condition that involves the cavernous sinus and orbital apex and is essentially a clinical diagnosis of exclusion.

Epidemiology

The estimated incidence of Tolosa-Hunt syndrome is 1 per 1,000,000 person-years with an average age of onset at 41 years ¹⁴.

Associations

• inflammatory myofibroblastic tumour (IMT) ⁶

• idiopathic hypertrophic pachymeningitis (IHP) ⁶

Clinical presentation

Clinically it refers to the presence of a painful ophthalmoplegia secondary to surrounding cavernous sinus inflammation. Tolosa-Hunt syndrome is essentially a clinical diagnosis of exclusion.

Pathology

The constant pain that characterises the disorder is believed to be due to compression resulting from fibroblast proliferation and infiltration of lymphocytes and plasma cells, along with thickening of dura mater within the cavernous sinus ¹⁵. Occasional granulomas and giant cells have been reported ¹⁵.

Radiographic features

CT

May show asymmetrical enlargement in the region of the cavernous sinus on the affected side +/- contrast enhancement ¹.

The secondary criteria are internal carotid artery narrowing, extension towards the superior orbital fissure and orbital apex.

MRI

May show evidence of inflammatory changes in the region of the anterior cavernous sinus, superior orbital fissure +/- orbital apex. Signal characteristics are non-specific ¹⁰ (clinical scenario essential to diagnosis) but may include:

• T1: involved region is isointense ² to hyperintense ⁸ compared with muscle 

• T2: involved area is hyperintense

• T1 C+ (Gd): may show contrast enhancement during active phase with resolution of enhancement following treatment ^5,9

Treatment and prognosis

The condition is often successfully amenable to steroid treatment and does not usually require biopsy unless there is concern that it represents malignancy ¹⁵.

History and etymology

It was initially described by Eduardo Tolosa Colomer (1900-1981) ¹², a Spanish neurosurgeon, in 1954 ³ (note his son is a pioneering neurologist with a similar name: Eduardo Tolosa Sarró (fl. 2019)) and then by the American neurosurgeon William Edward Hunt (1921-1999) et al. in 1961 ^4,12. The disease is also known as painful opthalmoplegia.

Differential diagnosis

Consider other pathological processes presenting with similar clinical features such as meningioma, sarcoidosis, pituitary tumours, tuberculous meningitis, lymphoma, cavernous sinus thrombosis ¹³.