We report a case of a direct carotid–cavernous fistula (CCF) in a patient with Ehlers–Danlos syndrome type IV who presented with progressive chemosis and diplopia. To prevent potential lethal arterial wall injury due to the fragility of the arterial vessel wall, the ipsilateral carotid artery and internal jugular vein were surgically exposed for direct insertion of endovascular sheaths, and transvenous embolization was performed using triple microcatheters with detachable coils. The clinical course was uneventful, and chemosis and diplopia subsequently resolved. By the 6 month follow-up, MRI revealed no recurrence of the CCF. These techniques offer a unique access alternative for endovascular treatment, thereby reducing the risks associated with arterial dissection that often accompanies transfemoral access in this particular condition.
- Vessel Wall
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.
Ehlers–Danlos syndrome (EDS) type IV is a collagen vascular disease with an autosomal dominant inheritance caused by a COL3A1 mutation. EDS type IV, also called the vascular type EDS, is characterized by connective tissue fragility of the arteries, gastrointestinal tract, and viscera, and can present with arterial dissection, ruptured aneurysms, gastrointestinal perforation, and organ rupture. Spontaneous carotid–cavernous fistula (CCF) is the most frequent neurovascular complication associated with EDS type IV. Treatment of CCF in patients with EDS type IV is particularly challenging because of the extreme fragility of the blood vessels. Interventional treatment of CCF in EDS type IV is associated with a 58% morbidity rate and a 33% mortality rate.1 Some of these complications may have been due to arterial wall injury after transfemoral artery access.2 Fatal retroperitoneal bleeding has been reported because of iliac artery perforation after transfemoral artery access for CCF in EDS type IV patients.2 We describe a novel technique of open surgical access via the neck vessels to allow for transvenous embolization (TVE) of a CCF in EDS type IV that circumvents transfemoral catheterization.
A 24-year-old man presented with spontaneous pulsatile tinnitus, progressive headache, right chemosis, and right abducens nerve palsy. His mother had a history of dissection of the thoracic aorta and had been diagnosed with EDS type IV. His grandmother had died from cerebral apoplexy. The patient was diagnosed with EDS type IV based on clinical presentation, physical examination, family history, and confirmation of a mutation in the COL3A1 gene after the onset of CCF.
MR angiography revealed a right CCF, as evidenced by dilatation of the superior ophthalmic vein (SOV), superficial middle cerebral vein (SMCV), and right cavernous sinus (figure 1A, B). MR angiography also showed tortuous change of the right internal carotid artery (ICA) at the prepetrous portion. Susceptibility weighted venogram imaging showed marked venous congestion in the right cerebral hemisphere (figure 1C). Preoperative CT angiography did not show evidence of arterial dissection at the cervical portion of the right common carotid arterial wall.
To avoid transfemoral arteriography, we planned direct carotid artery and jugular vein puncture via direct neck dissection for the purposes of interventional coil embolization. Furthermore, we decided to undertake transvenous coil embolization using triple microcatheters to achieve safe and complete sinus packing without coil extension to the ICA via the fistula.
Written informed consent was obtained from the patient prior to the intervention.
Under general anesthesia, the carotid artery and jugular vein were exposed in the operating room. The common carotid artery was punctured, and an 11 cm 4 F sheath (Terumo, Japan) was introduced and placed just proximal to the tortuous change. The jugular vein was also punctured, and a 25 cm 5 F sheath (Terumo) was introduced to allow passage of the transvenous triple microcatheters to perform complete coil embolization (figure 2). The wound was closed around the sheaths, and the patient was heparinized before transfer from the operating room to the angiography suite.
Angiography confirmed a relatively large fistula between the C4 portion of the right ICA and the cavernous sinus. Venous drainage of this fistula involved the right SOV, right uncal vein, intercavernous sinus, right SMCV, and right inferior petrosal sinus (figure 3A). A guidewire balloon catheter (Hyperform 7×7 mm; Micro Therapeutics, USA) was introduced into the carotid siphon to prevent passage of coils through the fistula and as a marker of fistulous location. Triple microcatheters (Stryker, Michigan, USA) were advanced into the cavernous sinus via the right inferior petrosal sinus (figure 3B, C).
TVE was performed under cavernous sinus pressure monitoring through the microcatheter with uncal vein outflow occlusion to avoid deep venous congestion (figure 3D, black arrow), secondary SMCV outflow occlusion to avoid cerebral venous congestion (figure 3D, white arrow), right SOV outflow occlusion (figure 3E, white arrow), left SOV and intercavernous sinus outflow occlusion, and right cavernous sinus packing (figure 3E, black arrow) using a combination of triple microcatheters to avoid passage of coils into the ICA via the fistula. Finally, the fistula was completely occluded (figure 3E). We initially kept the balloon there but did not inflate it.
After TVE, the neck wound was opened again, and the sheaths were removed under direct vision. A purse string suture (Prolene 6-0; Ethicon Inc, Somerville, New Jersey, USA) was placed at the puncture site.
Outcome and follow-up
The patient was kept sedated and ventilated, and strict blood pressure control was instituted by monitoring with near infrared spectroscopy for 4 days in the intensive care unit to prevent intracerebral hematoma due to hyperperfusion syndrome. His symptoms completely resolved, and he was discharged from the hospital without neurological deficits. At the 6 month follow-up, MRI revealed no recurrence of the CCF (figure 4A, B) and decreased venous congestion in the right hemisphere.
EDS is a group of autosomal dominant diseases of the connective tissue characterized by abnormal collagen synthesis. EDS affects 1/5000 to 1/500 000 individuals.3 EDS type IV, known as vascular-type EDS, comprises 4% of EDS cases and is the most severe form of EDS.2 EDS type IV is characterized by fragile blood vessels and visceral walls, blood vessel rupture, aneurysms, dissections, and fistulas, as well as pneumothoraces and visceral rupture. The cumulative risk of vascular or visceral rupture is 80% by age 40 years.3 The most common non-lethal vascular complication is direct CCF, which is rupture of an intracavernous ICA aneurysm induced by the weakness of the arterial wall.
Despite recent advances in endovascular techniques, the treatment of CCF in patients with EDS type IV is very hazardous (due to the fragility of the vessels) and frequently results in poor outcomes. A review by Schievink et al4 reported a 58% mortality rate, with 23% attributed to complications of treatment for CCF with EDS type IV. Horowitz et al2 reported remote vascular catastrophes after transarterial balloon embolization for CCF in EDS type IV patients and recommended avoiding arterial puncture for diagnostic procedures. Most of these complications can be attributed to femoral arterial access, even during TVE of CCF. To prevent potential lethal arterial wall injury, Van Overmeire et al1 used pure TVE of CCF in EDS patients without arterial puncture for diagnostic and monitoring purposes during the procedure; however, the patient died of intraperitoneal hemorrhage 10 days after treatment, probably due to large caliber vein rupture.
In the present case, the ipsilateral carotid artery and internal jugular vein were surgically exposed by direct neck dissection for direct insertion of endovascular sheaths, thereby avoiding the risks of the usual transfemoral approach. TVE was performed using a combination of triple microcatheters introduced into the cavernous sinus, to facilitate complete cavernous sinus occlusion and recurrence, especially in a case of CCF with a relative large fistula, like in the present case. Furthermore, it is useful to measure intracavernous sinus pressure and access to dangerous drainage route during outflow occlusion. Balloon placement across the fistula is also helpful not only for preventing coil passage into the ICA via the fistula but also for identifying the precise fistulous location by its marker throughout the procedure. This information enables complete coil embolization without coil migration to the ICA. After TVE, the sheaths were removed under direct vision, and a purse string suture was placed at the puncture site, as an open procedure would minimize the risk of carotid dissection compared with blind carotid artery manual compression.
Recently, Khan et al5 reported successful embolization of CCF in patients with EDS type IV via direct puncture of the ICA. However, this strategy is associated with a persistent risk of ICA dissection; indeed, blind ICA puncture and manual compression of the puncture site is difficult because of the mandible overlying the artery, and hematoma could possibly cause airway compression. The direct percutaneous puncture approach is an effective and feasible approach6 but the risk of postoperative hemorrhage remains significant. Even in a patient with vascular fragility, such as patients with EDS, percutaneous puncture and repair of the vessel under direct vision is strongly recommended.7 Hollands et al8 described a case of initial surgical exposure of the ipsilateral carotid artery and the internal jugular vein with placement of endovascular sheaths instead of transfemoral access. However, two separate transvenous procedures were required to occlude high flow CCF using a single microcatheter. Furthermore, they achieved hemostasis by manual carotid artery compression after treatment, which increases the risk of carotid artery dissection.9
Desal et al10 described postoperative intracerebral hemorrhage after endovascular treatment for CCF with EDS and speculated that the complication was secondary to the reperfusion phenomena and dysautoregulation of cerebral flow. In the present case, the patient was kept sedated with strict blood pressure control by monitoring with near infrared spectroscopy for 4 days in the intensive care unit after treatment to minimize the stress to the fragile arterial wall and to prevent intracerebral hematoma due to hyperperfusion syndrome.
The limitations of the present technique are that there is a possibility of distal carotid dissection after placement of a 4 F sheath in the common carotid artery, and this technique allows only contralateral venous and arterial access.
In conclusion, this report describes a novel technique of open surgical access to neck vessels and an endovascular technique that minimizes the risk and sequelae of arterial dissection of a CCF in EDS type IV.
Treatment of carotid–cavernous fistula in patients with Ehlers–Danlos syndrome type IV is particularly challenging because of the extreme fragility of the blood vessels.
We describe the novel technique of surgical access to neck vessels, endovascular transvenous embolization using triple microcatheters, and postoperative management.
This technique offers a good access alternative for endovascular treatment, thereby preventing the high mortality rate otherwise associated with the transfemoral approach.
Contributors Data collection: IN and HSP. Writing the article: IN. Critical revision of the article: IN, HSP, TW, KT, HN, KK, and HN. Overall responsibility: IN, KK, and HN.
Competing interests None.
Patient consent Obtained.
Provenance and peer review Not commissioned; externally peer reviewed.