Life-Threatening Massive Epistaxis because of Ruptured Pseudo-aneurysm of Petrous Internal Carotid Artery and its Treatment with High-Flow Bypass

Sir, Aneurysms of the petrous internal carotid artery (ICA) are quite rare. Their exact incidence is not known. They can be congenital, traumatic, mycotic, and inflammatory in origin.[1] Mostly, they are asymptomatic but can present with symptoms such as cranial nerve palsies, epistaxis, otorrhagia, and pulsatile tinnitus.[2–4] Massive epistaxis caused by rupture of such aneurysm is quite rare.[5] Very few cases of petrous ICA aneurysms presenting with massive epistaxis are available in the literature [Table 1].[6–21] We report a case of the left petrous internal carotid artery pseudo-aneurysm presented with life-threatening epistaxis.Table 1: Review of literature of petrous ICA aneurysm presenting with epistaxisA 43-year-male patient was referred from the medical unit for management of left petrous internal carotid artery pseudo-aneurysm following two episodes of massive epistaxis. At the time of admission to neuro-surgical services, he was fully conscious and well awake. His higher functions were normal, and he had mild left facial paresis. His other neurological examination revealed no abnormality. Earlier, he was admitted to the otorhinolaryngology department 3 months back with a foul-smelling left ear discharge for 15 days. His hematological investigation showed uncontrolled blood sugar (with a blood sugar of 400 mg/dl and an HbA1c level of about 10). He was diagnosed with acute suppurative otitis media (ASOM) and underwent a left ear myringotomy. The patient had bloody nasal discharge post-procedure, so a paranasal sinus computed tomography (CT) scan was performed, suggestive of acute invasive fungal sinusitis. He then underwent FESS (functional Endoscopic sinus surgery) with endoscopic debridement of fungal sinusitis. The culture reports were suggestive of mucormycosis (zygomycetes species), so he was treated with oral posiconazole and discharged with anti-diabetic medications. About 2 weeks later, he again presented in EMS (Emergency Medical Services) with massive epistaxis. His nose was packed, and the bleeding stopped. He was managed conservatively with intravenous fluids, anti-fibrinolytic medication, and blood transfusion. The nasal pack was removed after 48 hours, and there was no bleed. Subsequently, he underwent oesophago-gastro-duodeno (OGD) scopy, which was normal. Therefore, he was discharged with anti-diabetic medications and hematinics. One week later, he again presented in EMS with hypovolemic shock because of massive epistaxis. He required multiple blood transfusions, fresh frozen plasma (FFP), intravenous (IV) fluids, and inotropic support. He stabilized over 1 week and underwent CT scan and CT angiography of brain and neck vessels, which revealed irregular lobulated outpouching of about 2.5 × 1.2 × 1.6 cm size arising from the petrous segment of left ICA and protruding beyond the eroded sphenoid bone, suggestive of pseudo-aneurysm. He was then transferred to the neuro-surgical unit. His cerebral DSA (digital subtraction angiography) revealed an irregular giant outpouching arising from the petrous segment of the left internal carotid artery, suggestive of pseudo-aneurysm [Figure 1a-c]. DSA also revealed filling of only the right middle cerebral artery on the right ICA injection and filling of both the anterior cerebral artery and left middle cerebral artery on the left ICA injection. It was a suggestive absence of crossflow across the anterior communicating artery, so balloon occlusion test was not necessary. Three-dimensional rotational angiography was performed to understand better the anatomical configuration of aneurysm and treatment planning [Figure 1c]. Endovascular and surgical treatment options were discussed with the patient and his family members. With due consent, double bypass procedures followed by ligation of the internal carotid artery in the neck were planned. Double bypass includes low-flow superficial temporal artery to middle cerebral artery (STA-MCA) bypass and high-flow external carotid internal carotid (EC-IC) bypass using saphenous venous graft.Figure 1: Cerebral DSA showing irregular giant outpouching arising from the petrous portion of the left internal carotid artery, suggestive of pseudo-aneurysm; anteroposterior view (a) and lateral view (b). Three-dimensional rotational angiography showing the morphology of the aneurysm and pre-aneurysmal narrowing of the artery lateral view (c)Under general anesthesia, the head fixed with Mayfield clamp and left frontotemporal scalp flap was elevated preserving the superficial temporal artery. Left frontotemporal craniotomy was performed. Under a microscope with the high-magnification left angular artery, a branch of the middle cerebral artery was defined. The frontal branch of the superficial temporal artery to the angular artery end to side anastomosis was performed using 10-0 ethilon. After completing prophylactic and protecting STA-MCA low-flow bypass, the left sylvian fissure was opened. A vertical skin incision in the neck and the carotid confluence (the common carotid, external and internal carotid arteries) was dissected. A saphenous vein graft was harvested from the ankle to the knee on the left leg and flushed with heparinized saline. The saphenous venous graft was positioned using a chest tube from carotid confluence to intra-cranial space such that it was deep to the zygoma, temporal muscle, and digastric muscle. The inferior division of the M2 branch of the middle cerebral artery was selected, and the saphenous vein to the middle cerebral artery end to side anastomosis was performed using 9-0 ethilon. The proximal end of the venous graft was anastomosed with a proximal external carotid artery in the neck (end to side manner) using 7-0 prolene. After confirming the adequate flow across the bypass using indocyanine green (ICG) and vascular Doppler, the left internal carotid artery was ligated with 1-0 silk in the neck just above its origin. Hemostasis was assured, and all the wounds closed in layers. The post-procedure recovery of the patient was uneventful. He received 150 mg of aspirin on the first post-operative day and was continued. The patient developed epidural collection post-procedure day 5, for which epidural tapping was performed. He also had mild speech impairment, which recovered over 3 weeks. The patient was discharged on day 7. Post-operative DSA revealed intact bypass, both high flow and low flow, with complete disappearance of the aneurysm [Figures 2a-b and 3a-b]. After 6 months of clinical follow-up, the patient was completely normal without any neurological deficit.Figure 2: Post-operative cerebral DSA left ECA injection showing intact bypass; antero-posterior view (a) and lateral view (b) with good distal flow and complete disappearance of an aneurysmFigure 3: Three-dimensional rotational angiography arrows showing the high-flow bypass site on lateral view (a) and the low-flow bypass site on the antero-posterior view (b)A pseudo-aneurysm is a blood-filled pseudo-vascular space adjacent to the vessel, and the wall is formed by reactive connective tissues. The aneurysm does not contain any layer of the vessel wall. The cervical ICA is commonly involved. Pseudo-aneurysms of petrous ICA are quite rare.[22] They are usually fusiform in their morphology and congenital in origin.[23] Other causes of pseudo-aneurysms include traumatic, mycotic, neoplasm, iatrogenic, and radiation-induced.[1] Mycotic aneurysms are rare among all documented petrous ICA aneurysms.[21] They result from an infection of the adventitia because of middle ear pathology. Other causes include chronic otomastoiditis, tonsillar and pharyngeal infections, and cholesteatomas. The osseous erosion is because of chronic infection and enlargement of an aneurysm within the bone.[24] Most of the aneurysms of petrous ICA are asymptomatic but can produce a wide range of symptoms, depending on the size and growth within the canal. Incidence of symptoms is usually higher in the third decade of life and has a female predominance.[25] The most common symptoms include headache, dizziness, and hearing loss. Some patients can also present with Horner’s syndrome because of the involvement of the sympathetic plexus in this area.[26] Extension into the middle ear cavity may lead to pulsatile tinnitus, facial nerve palsy, progressive hearing loss, and vertigo. Multiple cranial nerve palsies ranging from the third nerve to the eighth nerve are also reported.[15] When these aneurysms rupture, the patient may present with massive bleeding with symptoms ranging from hemotympanum, otorrhagia, and epistaxis.[11] Very few cases have been reported in the literature, where a petrous ICA aneurysm causes epistaxis, as mentioned in Table 1. In recent years, mortality has been significantly less because of immediate diagnosis and minimum time to intervention. The first case of petrous ICA aneurysm with epistaxis was reported by Busby et al.[6] in 1968, where a patient died in spite of proximal ligation of ICA. In our case, the patient presented with purulent ear discharge and massive epistaxis because of a fungal infection. As most pseudo-aneurysms are asymptomatic, the diagnosis is generally incidental in patients who undergo CT for some other reasons. On CT, these aneurysms occur along the eroded part of the petrous part of the carotid canal.[15] Magnetic resonance imaging (MRI) shows rapid flow in T1- and T2-weighted images in aneurysms with the patent flow and laminated appearance if thrombosis is present. MR angiography can give a clear orientation of the aneurysm. A definitive diagnosis is usually provided by DSA, based on which appropriate treatment can be planned.[27] Treatment of petrous ICA aneurysm includes either endovascular or surgical. Endovascular options include occlusion of the carotid artery using coils and balloons after performing a balloon occlusion test or coiling of the aneurysm along with stents, use of covered stents, and use of flow diverters to preserve the flow of the internal carotid artery. Second, in pseudo-aneurysm, as there is no true wall to the aneurysm and the surrounding osteonecrotic bone does not offer enough support to the coil and pseudo-aneurysm, the use of coils is complicated.[12] In our case, we have thought of two different options, flow diverter and covered stent. The diameter of the internal carotid artery distal to the neck of pseudo-aneurysm (distal landing zone) was about 6 mm size. The largest diameter of the flow diverter available was 5 mm. Also, there was significant narrowing of the artery proximal to the neck. Because of above reasons, the flow diverter was out of question. Covered stent at this location is difficult to navigate in the tortuous internal carotid artery. Also, we were concerned about possible rupture of pseudo-aneurysm following use of endovascular device because of the fragile nature of pseudo-aneurysm. Management of this kind of aneurysm is quite challenging surgically because of the anatomic inaccessibility to this region. Surgical options include proximal ligation of the ICA after performing a balloon occlusion test or bypass methods in the form of high-flow bypass (EC-IC bypass) and low-flow bypass (STA-MCA bypass).[21] In our literature review, most of the case reports have suggested the sacrifice of the internal carotid by endovascular trapping or proximal ligation of the artery (58%).[6–21] However, in our case, as the dominant flow was from the left internal carotid artery and there was no crossflow from the right side, we did not sacrifice the artery; also, to be doubly sure of the flow patency, we did a double bypass, high flow (EC-IC bypass) and low flow (STA-MCA bypass). Finally, the graft supplied blood flow to four major arterial (left middle cerebral, both anterior cerebral and left posterior cerebral) territories. Pseudo-aneurysms of petrous ICA are very uncommon and diagnosed on imaging for other reasons as they are asymptomatic. In cases of severe epistaxis of an unknown cause, diagnostic angiography should be performed to rule out petrous ICA aneurysms. Endovascular treatment is a minimally invasive procedure and should be considered if feasible. Surgical treatment options include proximal ligation or trapping of ICA if the patient sustains balloon occlusion test, or bypass is considered if the patient fails balloon occlusion test. Declaration of patient consent The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.