Introduction

Extracranial carotid artery aneurysms (ECAA) are a rare finding, accounting for only 1% of all carotid diseases¹,², although due to its rarity, true incidence is still unknown¹,³. The majority of ECAA are mostly secondary to degenerative diseases (atherosclerosis), post-traumatic causes (such as penetrating traumas and iatrogenic injuries), post-endarterectomy aneurysms, local head-and-neck history of infections, and connective tissue disorder (arterial dysplasia, Ehlers-Danlos syndrome, and between others), most cases being able to associate the cause directly to the prevalence of group age²-⁵. A rising and more popular practice in the western hemisphere, yoga, has appeared and modeled new mechanisms of injuries within those practitioners. The most common and severe injuries involve the neck and shoulders due to repetitive low impact microtrauma and excessive exercise postures⁶.

Within the neck injuries, the relationship between the styloid process and its proximity to the Carotid arteries, might not be as casual as previously thought. The carotid artery and its bifurcation located within the dense fascia, does not make the rotational movement with the skull but rather with the neck, to the opposing movement of the styloid process rotation of the skull, from this mechanism of action, excessive rotating of the neck, might predispose microtraumas from such practices like yoga, resulting in a degenerative process of the anatomic area⁷.

Clinical findings range from pulsatile mass (being the most common symptom) presenting as a painless neck mass². Neurologic symptoms secondary to atheroembolism from the aneurysmal sac or due to direct compression of the ECAA creating a mass effect and stroke rate ranging from% 50 to 70%²,⁴.

The diagnostic pathway ranges from duplex ultrasound as an initial diagnostic tool, to magnetic resonance and computerized tomography angiography (CTA) to provide intracraneal imaging³. Although hemorrhage and rupture are very uncommon ways of manifestations, it is recommended to intervene all aneurysms, even asymptomatic cases, due to high prevalence of neurological events³,⁸,⁹. The treatment of choice should be fitted to every patient and needs. Surgical options embody ligation, extracranial to intracranial bypasses (which has been left as meer anecdotal or in life threatening scenarios)¹⁰,¹¹, resection and reconstruction using autologous or prosthetic grafts for tortuous ECAA aneurysms allow resection and a primary end-to-end anastomosis¹,⁴,⁸,¹². Endovascular therapy may be advantageous for selected cases⁸,⁹, reducing cranial nerve injuries and periprocedural complications, although due to the anatomical features of the aneurysms, open surgery still remains to be the standard procedure¹,³,¹³.

Case report

A 54-year-old female patient, originally from the Caribbean, active smoker and intense yoga practitioner, was referred to vascular surgery due to an acute appearance of a lump in the right side of the neck 3 weeks of evolution. Denying catheterization of intravenous access, trauma, fever, head-and-neck or local infections.

Physical examination revealed a pulsatile mass on the right side of the neck without external signs of compilation, skin suffering, or neurological focality, rest of the examination was anodyne. Laboratory tests with inflammatory reaction parameters came back normal.

To further evaluate the pulsatile mass, the right supra aortic trunk ultrasound duplex was performed, revealing a patent 1.6 cm anteroposterior diameter internal carotid artery (ICA) dependent saccular aneurysm is seen on the proximal third, with no evidence of atherosclerosis dissection or thrombus images, no hemodynamic repercussion and anterograde flow throughout the artery (Figs. 1 and 2). Common carotid artery with a normal diameter of 0.6 cm. No intimal hyperplasia was seen. External carotid artery was 0.45 cm. Patent vertebral artery with anterograde flow was present.

Figure 1 Doppler ultrasound internal carotid artery: a patent saccular aneurysm is seen. 

Figure 2 Doppler ultrasound internal carotid artery (ICA): measurement of 1.6 cm ICA aneurysm 

Based on the imaging study, the diagnosis of a patent saccular aneurysm ICA dependent was made and surgical elective resection and reconstruction of the ICA aneurysm was decided. Under general anesthesia, open surgery was performed, visualizing an ACI dependent aneurysm no signs of local infections nor tissue-related affection (Fig. 3). Resection and a primary end-to-end anastomosis was performed (Fig. 4) with no intraoperative complication. Samples were taken for pathology analysis. Microbiology samples were sterile. Post-operative evaluation showed no neurological events or focality, with a favorable evolution. Patient was discharged asymptomatic 2 days after.

Figure 3 Intraoperative image: aneurysm under direct vision. 

Figure 4 Intraoperative image: an end-to-end anastomosis on the internal carotid artery is performed. 

Pathology samples described intense fibrosis and fragmentation of elastic fibers, compatible with a degenerative arterial aneurysm.

Extended study through CTA shows a 9 cm an idiopathic renal angiomyolipoma being studied by the urology department pending embolization, no other signs of arteriomegaly or aneurysm were seen on the study. The genetic team at our center, evaluated the patient concluding no findings of suggestive connective tissue disorders, including fibrodysplasia, vasculitis workshop or any related disease to justify a patient outreach study with no further follow up.

On annual revisions, ultrasound duplex demonstrated no signs of residual or new aneurysms, no intimal hyperplasia, slight elongation of the ICA, with no hemodynamic repercussion. Patient physical examination was normal (Figs. 5 and 6).

Figure 5 Doppler ultrasound internal carotid artery: yearly duplex examination was made, with normal anterograde flow and no sign of aneurysm is seen. 

Figure 6 Doppler ultrasound internal carotid artery (ICA): in the yearly follow-up, a patent ICA is seen with no aneurysmal lesions. 

Discussion

ICA aneurysms although being rare, the risk of transient ischemic attack or amaurosis fugax or less frequent and higher mortality, rupture, debut symptoms result it an important morbidity related pathology, where resection and reconstruction of a normal flow is recommended in nearly all cases¹,⁸. Although correlation to the aneurysm etiology with age and population seems to be the rule in nearly all patients³,¹⁰, mostly seen in older population or those who have gone through carotid endarterectomy, we must not let slip those cases where the clinical assessment or patient's history could be easily overlooked due to the scarcity of information related to a rare cause, in our case, a yoga practitioner. It might not be anecdotical the relationship between yoga poses and the resulting injuries deriving from this new and arising culture. Although the degenerative process of the aneurysm from the repetitive microtraumas of the styloid process would query for further anatomical findings, such as elongated styloid process or findings of indented arteries, it is important to consider our patient's background and conclude that the findings may have not occurred by chance.

Open surgery and endovascular repair are both valid and safe proven techniques, each with their own advantages¹². The anatomic area for surgical exposure will dictate, in most cases, which technique will fit reasonably¹³. Open surgery after exclusion of the aneurysmal sac from the artery can vary from primary closure, a patch, bypass grafts and in some, tortuous enough to perform an end-to-end anastomosis with excellent outcomes¹¹. Open surgery is most fitted to those lesions involving the proximal ICA. Endovascular repair is reversed for those fragile patients and/or where surgical exposure is impaired⁸. Options such as open surgery and endovascular procedure would have to be individualized to the patient's needs depending on size, location, and nature of the aneurysm.

Patient perspective

After the first post-operative year, patient resumed a more relaxed yoga practice. The patient expressed relieve from the favorable post-surgery development, although still concerns from what might have caused the aneurysm, and worried of the future diagnosis of the same nature. Overall she believes to lives a healthy lifestyle, but will do yearly check-ups with corresponding health-care physicians.

Conclusion

Therefore, to prevent any neurological deficits, and eventually low quality of life due to cognitive impairment, it is recommended to perform restoration of a normal anterograde flow. Our patient, with blank medical personal history of interest and a proximal ICA saccular aneurysm, underwent resection of the aneurysmal sac and primary end-to-end anastomosis, with no post-operative complications. During follow-ups, remaining asymptomatic, the genetic team discarded any suggestive finding of connective tissue disorder. Despite the efforts to affiliate any etiology, we remained with an idiopathic ICA dependent saccular aneurysm. As a reflection, we hypothesize whether intense yoga involving neck twisting may have played a role in the pathogenesis of carotid aneurysm, being, possibly, the first ICA aneurysm reported derived from this practice, increasingly common in the western hemisphere.