Cavernous sinus hemangioma

Cavernous sinus hemangioma is an uncommon cause of a cavernous sinus mass. Preoperative diagnosis is important to avoid unexpected surgical blood loss. 

Epidemiology

Cavernous hemangiomas of the cavernous sinus account for less than 1% of all parasellar masses ¹. They have a predilection for middle-aged women ¹. 

Clinical presentation

The presentation is usually due to mass effect on adjacent structures (especially cranial nerves within the sinus or the optic pathway). Presenting symptoms include diplopia due to extraocular muscle dysfunction (CN III, CN IV and CN VI) and visual loss (CN II) and facial numbness (CN V) ¹. When large the mass can also result in symptoms from mass effect, such as a headache ¹. 

Radiographic features

MRI

The key features that are helpful in making the diagnosis are a 'soft' appearing mass centered on the cavernous sinus, with pronounced T2 hyperintensity and contrast enhancement ^1-2. 

• T1: hypointense to brain
• T2: markedly high signal intensity
• T1 C+
  • vivid homogeneous enhancement
  • gradual filling in on dynamic sequences (similar to cavernous hemangiomas elsewhere) 

Nuclear Medicine

Accumulation of ^99mTc pertechnetate–labeled red blood cells within the cavernous sinus with scintigraphic imaging techniques is specific for cavernous hemangiomas ³.

Treatment and prognosis

Surgical resection can be challenging due to blood loss, especially if the diagnosis is not suspected pre-operatively, resulting in high intraoperative mortality, up to 12.5% in the literature ² (although this is probably in large part due to reporting bias). 

Differential diagnosis

The differential is essentially that of other cavernous sinus masses, with the main entities to be considered including: 

• trigeminal schwannoma
  • often 'firmer' in contour and mass effect
  • not as bright on T2 WI
  • cystic change common
  • dumbbell shape extending posteriorly along the trigeminal nerve
• meningioma
  • usually isointense to grey matter on both T1 and T2 weighted images
  • microcystic variant can have similar imaging features but are uncommon
  • meningiomas encasing the cavernous ICA usually result in luminal narrowing of the vessel, a feature that is not commonly seen with cavernous hemangiomas ³
• chondrosarcoma
  • arises from bone rather than the sinus
  • 'firmer' in contour and mass effect
  • chondroid calcification
• chordoma
  • enhancement minor
  • bony involvement
  • midline posterior extension often prominent
• pituitary macroadenoma
  • centered on pituitary fossa and no normal pituitary visible
  • usually not as bright on T2
  • less vivid enhancement