Transvenous approach for the treatment of direct carotid cavernous fistula following flow diverter embolization of cavernous carotid aneurysm

Patient presentation

• A 54-year-old female patient presented with acute diplopia.
• MRA showed 18.0 × 10.3 mm intracranial aneurysm located in the cavernous segment of the right internal carotid artery.
• Derivo (6.0 × 20 mm) deployed across the neck of the aneurysm. The postoperative course was uneventful, and the patient was discharged 3 days post-procedure.
• On post-procedure day 30, her right oculomotor nerve palsy had worsened and she had developed right abducens nerve palsy, right exophthalmos, and right chemosis.
• Angiography demonstrated right direct CCF because of rupture of the aneurysm that had been treated with FD.

CASE

Figure 1

• Right cavernous carotid artery aneurysm
• (A) Lateral 3D angiogram right internal carotid artery (ICA) C4 aneurysm, non-thrombosed.
• (B) Right internal carotid digital subtraction angiography (DSA)
• (B: A: lateral view) demonstrating 10 mm wide-necked aneurysm along the horizontal segment of the right cavernous carotid artery.
• (C) Lateral native fluoroscopy image during surgery / partially deploying FD/Derivo/.
• (D) ICA DSA (lateral view) after implantation of the Flow diverter with pronounced contrast stasis(asterisk) within the aneurysm consistent with flow remodeling.

Figure 2

• Anterior-posterior projection of a right common carotid angiogram showing a complex Barrow Type D indirect CCF.

Questions:

• Endovascular treatment;
  • Telescopic FD, Trapping, Trans-venous embolization
• Surgical treatment;
  • Clipping, bypass
  • DAFT or SAFT?

Figure 2

• Anterior-posterior projection of a right common carotid angiogram showing a complex Barrow Type D indirect CCF.

After 6-month follow-up

Carotid-cavernous fistula after flow diverter deployment

• Placement of a flow-diversion device can increase in the intra-aneurysmal pressure, which can potentially cause the rupture of the aneurysm, especially giant aneurysms that may have very weak walls.
• A rare complication following FD placement is delayed aneurysm rupture. 
• Analysis of the International Retrospective Study of Pipeline Embolization Device (IntrePED) registry of 580 aneurysms treated worldwide with PED revealed only three spontaneous aneurysm ruptures after PED implantation, an incidence of 0.6%
• The European Society of Minimally Invasive Neurological Therapies (ESMINT) Retrospective Analysis of Delayed Aneurysm Ruptures (RADAR) study found 14 delayed aneurysm ruptures among 1421 aneurysms treated with flow diverters, an incidence of 1%.
• CCF cannot be treated via a trans-arterial approach in patients treated with FD due to the low porosity FD device preventing access into the aneurysm.