Case Report
A Case of Cavernous Sinus Dural Arteriovenous Fistula with Persistent Left Superior Vena Cava
2025 Volume 19 Issue 1 Article ID: cr.2024-0047
Details
2025 Volume 19 Issue 1 Article ID: cr.2024-0047
Objective: Persistent left superior vena cava (PLSVC) is rare, occurring in approximately 0.3%–0.5% of the population. In endovascular treatment (EVT), the left internal jugular vein (IJV) is approached via the left innominate vein from the superior vena cava; however, the left innominate vein is occasionally absent in patients with PLSVC. Careful consideration is required when performing EVT, particularly transvenous embolization (TVE).
Case Presentation: A 70-year-old female presented with a left cavernous sinus dural arteriovenous fistula. Left external carotid angiography findings showed that multiple feeders from the ascending pharyngeal artery, accessory meningeal artery, middle meningeal artery, and the artery of the foramen rotundum had formed a shunted pouch posterolateral to the left cavernous sinus. We initially planned to perform a TVE via the right femoral vein. However, PLSVC was detected on common carotid artery angiography. Consequently, a TVE via the left IJV and coil embolization were performed, resulting in the disappearance of the shunt. The patient was discharged without neurological deficits. PLSVC is a rarely observed thoracic venous malformation, with few reports concerning its management in cerebrovascular EVT. Contrast-enhanced computed tomography is useful for diagnosis; however, most patients with PLSVC are clinically asymptomatic and this abnormality is typically an incidental finding, remaining challenging to detect during a preoperative examination.
Conclusion: It is essential to consider the possibility of PLSVC and to verify the appropriate access route, including the right atrial level and the venous phase, during preoperative cerebral angiography.
Persistent left superior vena cava (PLSVC) is rare, occurring in approximately 0.3%–0.5% of healthy individuals and 1.3%–4.5% of those with additional cardiac defects. PLSVC may be present during the early embryonic period but usually becomes absorbed and attenuated during development. Persistence of the left anterior cardinal vein, which is normally obliterated during embryogenesis, results in a PLSVC.
In endovascular treatment (EVT), the left internal jugular vein (IJV) is approached via the left innominate vein from the superior vena cava; however, this left innominate vein is occasionally absent in patients with PLSVC. Here, we report the first case of a patient requiring a trans-left IJV approach for a left cavernous sinus dural arteriovenous fistula (dAVF) owing to a PLSVC.
A 70-year-old woman with a history of hypertension and dyslipidemia complained of a 3-month history of worsening diplopia. She presented with sixth nerve palsy. MRI conducted at a nearby clinic revealed findings suggestive of a left cavernous sinus dAVF and she was referred to our hospital for consultation. She was conscious on the first presentation. Her left eye was in an adducted position, with conjunctival congestion in the left bulb, indicating a significant abduction disorder, and she experienced diplopia when looking to the left or down.
Figure 1 shows the initial MRA findings, which identified a high-intensity signal from the left cavernous sinus to the dilated superior ophthalmic vein (SOV) (Fig. 1A–1E), while arterial spin labeling (ASL) exhibited a high-intensity signal (Fig. 1F).
The patient was admitted to the hospital with a diagnosis of symptomatic left cavernous sinus dAVF, and a cerebral angiography was performed. Right internal carotid artery (ICA) angiography revealed a faintly visible left cavernous sinus through the meningeal branch (Fig. 2A), but no right external carotid artery (ECA) or left vertebral artery involvement was observed. Left ICA angiography showed flow from the meningeal branch and recurrent meningeal artery into the cavernous sinus. (Fig. 2B). Left ECA angiography and cone beam CT revealed that diffuse feeders, mainly the accessory meningeal artery, middle meningeal artery, ascending pharyngeal artery, and the artery of foramen rotundum (AFR), had converged to form a shunting pouch posterolateral to the cavernous sinus, with drainage into the SOV (Fig. 2C–2F).
Compared to the inferior petrosal sinus (IPS), the facial vein to the angular vein was relatively less tortuous (Fig. 2G and 2H); therefore, we planned a transvenous embolization (TVE) via this approach route and performed the TVE under general anesthesia 1 week later. A 4 Fr sheath was inserted into the right femoral artery and a 6 Fr guiding sheath was inserted into the right femoral vein. Angiography of the common carotid artery, including a venous phase at the right atrial level to confirm the approach route, revealed the PLSVC (Fig. 3A). Therefore, the left IJV was punctured and a TVE was undertaken via an IPS approach. After the shunt pouch was tightly packed with a coil, blood flow decreased but continued slightly, so additional coil embolization was performed above and below the coil mass of the shunt pouch, and the shunt disappeared (Fig. 3B and 3C). The patient was discharged without any neurological deficits.
Contrast-enhanced CT was performed at a later date, confirming that the PLSVC had opened into the right atrium via the coronary sinus, thereby establishing a definitive diagnosis (Fig. 4A–4E).
Informed consent was obtained from the patient for the publication of this case report and accompanying images.
PLSVC is observed in 0.3%–0.5% of the total population and 2%–4% of patients with congenital heart disease. During the embryonic period, venous blood from the head is returned to the heart via the anterior cardinal veins bilaterally, which merge with the posterior cardinal vein ascending from the caudal side to form the common cardinal vein. The caudal side of the right anterior cardinal vein and the right common cardinal vein later become the superior vena cava, while the caudal side of the left anterior superior vein from the innominate vein and the left common cardinal vein degenerate to become the ligament of Marshall. If this degeneration does not occur, a PLSVC develops (Fig. 5A and 5B), which is typically asymptomatic.1,2)
Along with cases lacking the left innominate vein (Fig. 5C), there are various other morphologies, such as those lacking the right superior vena cava, those lacking the coronary sinus, and those with malformations of the inferior vena cava, with 8% of cases involving flow into the left atrium.2–5)
Most cases are clinically asymptomatic,1,2) and many are incidentally discovered during procedures such as at the time of cardiac pacemaker insertion or central venous catheter insertion through the left subclavian vein.6)
Only 1 case of TVE performed on an intracranial dAVF with PLSVC has previously been reported.7)
In this case report, given it was not possible to access the left innominate vein from the superior vena cava, a route to the left side was explored at a lower cardiac level, and the left IJV was approached via the PLSVC.
When approaching the left IJV, the left innominate vein is typically accessed from the superior vena cava. However, it has been reported that in 65% of patients with PLSVC, the left innominate vein is absent or hypoplastic.7) In such cases, it is necessary to approach the left jugular vein via the PLSVC or through direct puncture. However, when approaching via the PLSVC, it is necessary to find a route to the left side considering the heart’s position, as mentioned in the previous case report.7)
However, in certain reported cases, blood flows into the left atrium, and other vascular/cardiac malformations are also present.2–4) Given the complexity of such cases and the potential time required to identify the approach route, an approach using an IJV puncture might be more effective. This approach was not attempted in this case; however, it might be possible to guide the microcatheter from the right IJV via the right IPS and then approach the shunt cavity of the left cavernous sinus via the basilar plexus or internal cavernous sinus. Contrast-enhanced CT is valuable for diagnosis and was used to confirm the diagnosis in our patient. However, identifying PLSVC through standard examinations upon admission is challenging as most patients with PLSVC are asymptomatic. Therefore, in clinical practice, when performing preoperative cerebral angiography, the possibility of PLSVC should be considered and treated after confirmation of the appropriate approach route, including the right atrial level and venous phase.
PLSVC is rare; however, its possibility should be considered during TVE, especially when preoperative cerebral angiography is performed, and confirming the approach route is extremely important. In such cases, an approach involving an IJV puncture may prove effective.
H.N.: Conceptualization, methodology, software, writing—original draft preparation, visualization, investigation, software, validation. Y.M.: Review, editing, and supervision. K.O.: Reviewing and editing. T.H.: Review, editing, and supervision. T.M.: review, editing, and supervision.
This research did not receive any specific grants from funding agencies in the public, commercial, or not-for-profit sectors.
The authors declare that they have no conflicts of interest.
