Carotid Cavernous Fistula (Grand Rounds)

From EyeWiki

Is that the ocean?

David Chin Yee

Henry Ford Hospital


Financial Disclosure

  • Dr. Chin Yee states that he has no financial interest, affiliation or other relationship with the manufacture of any commercial project discussed or with the manufacture of any competing commercial project.

Chief Complaint

“Red and puffy Right Eye”


History of Present Illness

  • 56 YO CF redness, swelling and "puffyness" of right eye
  • Worsening of baseline vertical binocular diplopia (>2 yrs)
  • Headache with use of ibuprofen 6-8 tablets a day for the past month
  • Went initially to optometrist one month prior started on abx drops, two weeks later no improvement placed on PF, one more week referred to Ophthalmologist

Medical History

  • Past Ocular History: 2 year hx of diplopia corrected with prism, no trauma or past surgery
  • Past Medical History: Asthma, Arthritis
  • Medications: Zyrtec, Ibuprofen
  • Family History: Non-pertinent
  • Social History: negative for drugs, tobacco or alcohol


  • Visual Acuity (without correction)
    • 20/25 OD
    • 20/25 os
  • Pupils: OD 4mm dark, 2mm light; OS 4 mm dark, 2mm light; No relative afferent pupillary defect (RAPD)
  • IOP: 31 mmHg OD; 20 mmHg OS
  • Confrontation visual fields: Full OD and OS
  • Hertel (marco): 22 mm OD, 17 mm OS base 92.
    • Increased proptosis with Valsalva
  • External Examination: Engorgement of the right upper and lower eyelids; question of orbital bruit present over the right eye, no neck bruit, no skin lesions
  • Palpebral Aperture: OD: 7mm, OS: 9mm
  • Anterior segment exam: Conj injection and chemosis OD. Early Cataracts. Otherwise nml examination OU
  • Dilated funduscopic exam: Normal Macula, vasculature and periphery OU

External Examination

DCY Slide9.JPG DCY Slide10.JPG

Fundus Examination

DCY Slide11.JPG

Imaging Testing

DCY Slide12.JPG DCY Slide13.JPG DCY Slide14.JPG DCY Slide15.JPG

Differential Diagnosis

  • Infections e.g., orbital cellulitis, mucormycosis and tuberculosis etc.
  • Inflammations e.g., sarcoidosis, orbital pseudotumor and Tolosa-Hunt syndrome etc.
  • Orbital vasculitis e.g., polyarteritis nodosa, granulomatosis with polyangiitis, etc.

  • Orbital Hemorrhage
  • Conjunctivitis
  • Orbital Varix
  • Thyroid Eye Disease
  • Myasthenia Gravis
  • CPEO
  • Space Occupying lesion within the cavernous sinus - Cavernous sinus syndrome

Cavernous Sinus Syndrome

  • Cavernous Sinus Tumor
  • Cavernous Sinus Aneurysm / AV Malformation
  • Cavernous Sinus Thrombosis
  • Inflammatory lesions
  • Carotid-Cavernous Fistulas

Final Diagnosis

  • Carotid-Cavernous Fistula
    • Abnormal communication between the venous cavernous sinus and the carotid artery.
    • Commonly masqueraded as Conjunctivitis delaying diagnosis

Cavernous Sinus

  • Trabeculated venous cavern on each side of the sphenoid sinus.
  • Receives blood via the superior and inferior ophthalmic veins, and drains into the jugular vein via the inferior and superior petrosal sinuses

Carotid Cavernous Fistula


  • A traumatic/direct CCF - direct communication between the internal carotid artery and the cavernous sinus.
  • Spontaneous/indirect CCF - occurring most often in middle-aged women, there are multiple dural feeders and numerous microfistulas within the cavernous sinus wall.


  • CCFs classified based on anatomical, etiological and hemodynamic factors.
  • Anatomically CCF divided into fast/ high-flow or slow/low-flow dynamics
  • Barrow's classified CCFs based on their communication into 4 subtypes


Barrow's CCF classification
Type Description
A Fistulous supply from the Internal carotid artery (direct fast-flow)
B Supply from the dural branches of internal carotid artery
C Supply from the dural branches of external carotid artery
D Combined forms
  • Fast flow direct
    • Head trauma or GSW 75%
    • Direct orbital trauma
    • Dissection of ICA
    • Ruptured cavernous aneurysm 25%
    • Iatrogenic complication during thrombectomy
  • Slow flow Indirect
    • Sinus infection
    • Phlebitis
    • Pregnancy and postpartum
    • HTN and Atherosclerotic disease

Mechanism Of Symptoms

  • Compression and Ischemia related to increased venous pressure and reduced arterial pressure
  • Flow reversal leads to engorged ophthalmic veins causing proptosis, conjunctival injection, chemosis and other neuro-ophthalmic symptoms (CN palsies).
  • Patients complain of retro-orbital headache, or a bruit. Facial pain with VI and V2 involvement


  • Ptosis, red, chemotic conjunctiva, increased IOP from increased episcleral venous pressure, anterior segment ischemia, pulsatile proptosis, Bruit and thrill, Muscle palsies, angle-closure glaucoma
  • Retinal findings: IntraRetinal Hemmorhages, Retinal Detachment, Vitreous Hemorrhage, disc edema and choroidal folds and effusions


  • Decreased Vision
  • Pulsatile tinnitus
  • Diploplia
  • Proptosis
  • Headache

Clinical Presentation

  • Depends on Type and size of the fistula as well as its location, blood flow rate and drainage route.
  • Posterior drainage (inferior petrosal sinus) - usually no ocular symptoms
  • Ocular signs and symptoms typically arise as the drainage shifts to an anterior route via the superior and inferior ophthalmic veins.
  • Because of their lower flow rate, dural CCFs usually produce less severe symptoms.
  • Objective and subjective bruits also are less common with dural fistulas.

Main Indicators for Treatment

  • Visual Deterioration
  • Glaucoma
  • Diplopia
  • Intolerable bruit or HA
  • Severe proptosis causing exposure keratopathy



  • Referral to interventional neurologist or neurosurgeon
  • Direct fistulas always require treatment
  • Various Modalities: coils, liquid embolic agents, balloon embolization, and stent placement
  • Success rate of closing fistula with these treatments range from 55-99%
  • Observe dural fistula's spontaneously close 20 - 50%
  • Potential complications: worsening nerve palsy and loss of vision


  • Patient completed embolization of cavernous sinus and fistula via transvenous approach by neurosurgery placing 15 coils.
  • Post-op Day 1: resolved proptosis, full EOM, no diploplia, stable vision, trace dilated conjunctival vessels, and good IOP (18 mmHg OU)

DCY Slide29.JPG DCY Slide30.JPG


Please use the discussion tab for this page to discuss this case.


  • Barrow DL, Spector RH, Braun IF, Landman JA, Tindal SC, Tindal GT. Classification and treatment of spontaneous carotid-cavernous sinus fistulas. J Neurosurg 1985;62:248-56.
  • Carotid-Cavernous Sinus Fistulas and Dural Shunts. Yanoff & Duker: Ophthalmology, 3rd ed.
  • Cavernous Sinus and Associated Syndromes (Multiple Ocular Motor Nerve Palsies). Wills Eye Manual. 5th edition.
  • Doran, Marianne. Carotid-Cavernous Fistulas: Prompt Diagnosis Improves Treatment. Clinical Update: Neuro-Ophthalmology. AAO.