Internal Jugular Vein Interposition Bypass for an Attigah Type II Extracranial Internal Carotid Artery Aneurysm: A Case Report of an Underused Autologous Conduit

Abstract

Introduction

Extracranial internal carotid artery aneurysms are uncommon and may cause cerebral ischaemia through embolisation or thrombosis. Attigah type II aneurysms require complex exposure, and conventional reconstruction options include saphenous vein grafts, prosthetic conduits, or arterial transposition. The use of the internal jugular vein (IJV) as an autologous conduit for a carotid aneurysm repair is rarely described in the literature. A case of a successful repair using this conduit is reported.

Report

A 69 year old man presented with a progressively enlarging right cervical mass. Computed tomography angiography demonstrated a 22 × 31 mm Attigah II extracranial internal carotid artery aneurysm with mural thrombus. An open repair was performed. After high cervical exposure and control of the carotid vessels, the external carotid artery was ligated, and the aneurysm was resected under shunting. A reversed ipsilateral IJV segment was used as an interposition graft, as bilateral great saphenous vein mapping showed inadequate diameters. Post-operative recovery was uneventful except for transient vocal cord paresis. No venous congestion developed despite IJV ligation. Duplex ultrasound at one and six months and computed tomography angiography at one year confirmed graft patency without stenosis.

Discussion

The IJV provides favourable calibre matching, wall characteristics, and harvest through the same cervical incision. This case demonstrates its feasibility as an autologous conduit when traditional options are unsuitable. IJV interposition may be considered a viable option for reconstructing complex Attigah II aneurysms.

Highlights

• •Attigah II internal carotid aneurysms are uncommon and technically complex.
• •This case introduces internal jugular vein interposition for carotid reconstruction.
• •The internal jugular vein provided a good calibre match and convenient anatomic access.
• •High cervical vascular maxillofacial exposure enabled controlled reconstruction.
• •One year follow up confirmed durable, complication free carotid reconstruction.

INTRODUCTION

Extracranial internal carotid artery aneurysms represent <1% of arterial aneurysms and pose a risk of cerebral ischaemia through embolisation or thrombosis, with rupture a much less frequent risk and typically in the context of infection.^1,2 The Attigah classification has facilitated uniform reporting and treatment planning; type II aneurysms, long, fusiform dilatations from the bulb to Blaisdell’s line, are the rarest, comprising approximately 3% in contemporary series.³ Their high cervical location often necessitates complex exposure, and arterial elongation or redundancy can preclude safe endovascular exclusion.^4,5 Although autologous saphenous vein grafts and prosthetic conduits are standard for reconstruction, the internal jugular vein (IJV) is rarely described for this indication, with only sporadic historical reports available. A successful IJV interposition graft for an Attigah II aneurysm is reported, and its advantages in this setting are discussed.

REPORT

A 69 year old ex-smoker with dyslipidaemia, previous anterior communicating artery aneurysm clipping, right upper lobectomy, and an open surgery popliteal aneurysm repair presented with a gradually enlarging right cervical mass. He remained neurologically asymptomatic. Duplex ultrasound and computed tomography angiography revealed a 22 × 31 mm fusiform Attigah type II aneurysm with mural thrombus. Mild ectasia of the left internal carotid artery was also noted, without haemodynamic significance. Crucially, the assessment of the intracranial circulation confirmed an intact circle of Willis, ensuring adequate collateral supply. The absence of concomitant abdominal aortic aneurysm was confirmed.

Open repair was selected (Figure 1, Figure 2, Figure 3). Pre-operative bilateral great saphenous vein (GSV) mapping showed inadequate diameters (<3 mm), being unsuitable as a conduit. Additionally, after addressing the diameters of the common carotid artery (12 mm), distal internal carotid artery (6 mm), and IJV (between 7 and 10 mm), it was considered that the calibre ratio was well within the acceptable limits for venous to arterial interposition, and the slight mismatch could easily be managed with slight distal spatulation. This prompted early preparation of a 5 cm ipsilateral IJV segment harvested through the same incision, reversed, and prepared for subsequent interposition.

Figure 1.

Pre-operative imaging of the extracranial internal carotid artery aneurysm. (A) Coronal computed tomography angiography demonstrating a fusiform Attigah type II aneurysm of the right internal carotid artery, extending from the carotid bulb towards the high cervical segment, with mural thrombus. (B) Three dimensional volume rendered reconstruction highlighting the aneurysmal dilation (R) and comparatively mild ectasia of the contralateral internal carotid artery (L). (C) Longitudinal multiplanar reconstruction showing the aneurysm’s length, tortuosity, and relationship to distal internal carotid artery segments.

Figure 2.

Operation steps for open reconstruction of an Attigah type II extracranial internal carotid artery aneurysm. (A) Patient positioning with nasotracheal intubation and left neck rotation to facilitate high cervical exposure. (B) Curved Schroeder incision and initial dissection. (C) Proximal and distal carotid control after division of the posterior belly of the digastric muscle and exposure of the aneurysmal segment. (D) T shaped opening of the aneurysm sac after clamping. (E) Shunt placement pre-loaded with the reversed internal jugular vein graft to facilitate the anastomosis. (F) Completed end to end interposition bypass from the common to the distal internal carotid artery using the reversed internal jugular vein graft.

Figure 3.

Post-operative follow up imaging after internal jugular vein interposition bypass. (A) Duplex ultrasound at six months demonstrating a widely patent graft with normal peak systolic velocities and preserved waveform morphology, without evidence of stenosis. (B) One year computed tomography angiography with three dimensional reconstruction showing patency of the reversed internal jugular vein interposition graft from the common to the distal internal carotid artery.

Nasotracheal intubation facilitated high cervical exposure. A curved Schroeder incision was made. Although maxillofacial surgical assistance was involved in the incision for potential mandibular subluxation, adequate exposure was ultimately achieved by dividing the posterior belly of the digastric muscle. The thyrolinguofacial trunk and external jugular vein were divided to expose the common, external, and internal carotid arteries, as well as superior thyroid artery. The hypoglossal nerve was preserved. The external carotid artery, incorporated into the aneurysmal wall, was ligated. After systemic weight based heparinisation, the carotid vessels were clamped in a standard sequence. The aneurysm sac was opened in a T shaped fashion. An Integra Sundt External Carotid Endarterectomy Shunt (Integra LifeSciences, Princeton, NJ, USA) was used. Pre-loaded with the reversed IJV graft, the shunt was introduced through the common carotid and into the distal internal carotid to facilitate subsequent anastomosis and maintain antegrade cerebral flow. An end to end bypass from the common carotid artery to the distal internal carotid artery was then constructed, and end to end anastomoses were performed with 5-0 and 6-0 polypropylene sutures. Clamp time was seventeen minutes. Heparin was not reversed. Robust pulsatile flow and a normal Doppler signal were confirmed before layered closure from the aneurysm sac to the skin and placement of a 16 Ch Redon drain. Peri-operative prophylaxis consisted of cefazolin 2 g and tobramycin 240 mg administered intravenously.

After surgery, the patient developed transient right vocal cord paresis treated with a short course of intravenous corticosteroids administered empirically. No venous congestion occurred despite ipsilateral jugular ligation. He was discharged on post-operative day three with aspirin 100 mg/d and atorvastatin 40 mg/d. Duplex ultrasound at one and six months and computed tomography angiography at one year confirmed graft patency without stenosis or thrombus. The patient remained neurologically intact.

Written informed consent for publication of this case and images was obtained. This report was prepared in accordance with the PROCESS 2020 guidelines.

DISCUSSION

Extracranial internal carotid artery aneurysms warrant intervention primarily to mitigate the risk of thromboembolic stroke. Although rupture is rare and typically associated with infection, the natural history of these lesions justifies surgical or endovascular management tailored to the individual anatomy. Attigah type II aneurysms represent the least prevalent subtype (∼3%) and pose a significant surgical challenge owing to their high extension towards the skull base.2, 3, 4, 5 Achieving adequate distal control often requires advanced exposure, such as the division of the posterior belly of the digastric muscle or mandibular subluxation, as considered in this case.

The choice between open repair and endovascular exclusion remains patient specific because both options have shown adequate results.6, 7, 8, 9 Open surgery was prioritised owing to its proven long term durability and the patient's low peri-operative risk profile. Although arterial elongation was present, the longitudinal extent of the aneurysm resulted in a significant gap after resection, precluding a tension free primary anastomosis. In the absence of a suitable GSV, the ipsilateral IJV emerged as an ideal autologous alternative.

The use of the IJV as an arterial conduit, originally reported by Mishaly et al.¹⁰ in 1992, remains an under used but robust concept. Compared with prosthetic grafts (polytetrafluoroethylene, Dacron), which carry risks of infection and compliance mismatch, the IJV offers superior biological integration. Its high elastin content provides structural resilience and a physiological compliance match that mimics the arterial wall better than the more collagenous GSV. Furthermore, its anatomic calibre (7–10 mm) ensures a seamless transition to the carotid system, and its harvest within the same surgical field avoids donor site morbidity. Although segmental IJV sacrifice is required, the redundancy of the cervical venous network typically prevents venous congestion, provided that the contralateral IJV is patent.

Technical nuances, such as the choice of anaesthesia and shunting, are critical in high level reconstructions. Although local anaesthesia allows for continuous neurological monitoring, general anaesthesia was selected to maintain a controlled environment during the complex distal dissection. To compensate for the lack of real time assessment, a double protection strategy was used: confirming an intact circle of Willis on pre-operative computed tomography angiography and using a prophylactic carotid shunt to ensure continuous cerebral perfusion during the prolonged clamping time necessitated by the Attigah II reconstruction.

Regarding post-operative complications, the transient vocal cord paresis observed was managed with an empirical short course of corticosteroids. Although high level evidence for this practice is lacking, it was implemented following multidisciplinary consultation to mitigate potential perineural oedema.

CONCLUSION

An IJV interposition graft is a feasible autologous reconstruction option for challenging Attigah type II aneurysms, when open repair is preferred, and GSV is unavailable. It is an anatomically convenient conduit, making it a valuable addition to the reconstructive armamentarium. Long term durability remains to be established, and strict lifelong surveillance is mandatory to monitor for potential graft occlusion or degeneration.

CONFLICT OF INTEREST

The authors declare no conflicts of interest.