Diagnostic and Therapeutic Challenges in Bilateral Carotid - Cavernous Fistula

Introduction This clinical case represents the spontaneous occurrence of a rare bilateral carotid - cavernous fistula (CCF) in an 81-year-old female patient, the symptoms of this pathology, diagnostic features and treatment. Case Presentation In December 2023, the patient was brought to the emergency department due to severe headache, eye redness and diplopia. She was unable to move her right eye laterally - the abducens nerve neuropathy was diagnosed. A computer tomography (CT) and CT angiography (CTA) scan was performed but revealed no abnormalities. During the follow - up in February 2024, the ability to move both eyes laterally became impaired. As the disease progressed, in March 2024 a selective angiography (ANG) was performed. It revealed a bilateral low - flow CCF supplied by an external carotid artery. An endovascular obliteration was performed, the cavernous sinus was partially obliterated and the shunting from the embolized branch ceased. Two days following the procedure, an improvement in ocular motility and eye redness was observed. The condition was stabilized and follow - up visits were scheduled. Discussion A CCF is a rare condition that forms due to damage of the cavernous carotid artery wall [1]. Spontaneous CCFs are more common in postmenopausal women [2][4]. Diagnostic tests and imaging for CCFs depend on the symptoms. Non - invasive imaging techniques like CT or CTA can reveal unspecific signs of CCFs. However, these techniques are limited in revealing low - flow CCFs or small fistulas. A golden standard for diagnosing CCFs is digital subtraction angiography (DSA), which reveals detailed fistula's anatomy [3]. For symptomatic CCFs, endovascular treatment is first line therapy [4]. Endovascular embolization can successfully treat more than 90% of cases [2][4]. Complications rate related to endovascular embolization of CCFs is about 10% and the majority of them are transient. 71% of all complications are cranial nerve palsies, with cranial nerve VI involved in 80% and cranial nerve IV in 20% of the cases [5]. Conclusions This case highlights a rare bilateral CCF that was detected only on selective ANG and successfully controlled by endovascular treatment.