A rare case of a carotid loop anomaly
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* Kanchana Seneviratne
* Karen Tam
* Ajantha Jayatunga
* Adibe Khanafer

A 70-year-old man with episodes of left sided amaurosis fugax presented with expressive dysphasia. His past medical history included ischaemic heart disease, myocardial infarction, hypercholesterolaemia and a previous right carotid endarterectomy (CEA) for symptomatic disease. Carotid Doppler studies and a computed tomography (CT) angiogram revealed an irregular left sided internal carotid artery (ICA) with 80% stenosis. Despite a multidisciplinary review, the surgeons’ attention was drawn to the fact that this anomaly existed. During the CEA a long redundant loop of ICA was found above the carotid bifurcation (fig 1). The surgery consisted of proximal ICA excision, endarterectomy of the bifurcation, followed by end-to-end anastomosis. Postoperative recovery was uneventful.

![Figure 1](http://casereports.bmj.com/https://casereports.bmj.com/content/casereports/2009/bcr.07.2008.0362/F1.medium.gif)

[Figure 1](http://casereports.bmj.com/content/2009/bcr.07.2008.0362/F1)

Figure 1 Intraoperative photograph.

Incidence of variations in the ICA lie between 10–40%, however the incidence of variations which cause symptomatic cerebrovascular insufficiency lies between 4–16%.1,2 Loss of arterial wall elasticity from atherosclerosis and hypertension leads to the more common presentation in the elderly.3 The ICA is derived from a coiled third aortic arch and the dorsal aortic root.3 Congenital tortuosities arise when failure to uncoil in the embryo occurs.3 It is more common in men (3:2) and 71% occur bilaterally, while 63% occur on the right.1,3

These variations tend to be symptomless, which makes this case interesting as the looping was discovered during surgery of the diseased vessel. It is important to be aware that these anomalies are not always incidental or asymptomatic and that maybe they can lead to symptoms of transient ischaemic attacks and even the possibility of strokes. Lack of awareness of this anomaly as in this case may lead to under-diagnosis and considerable anxiety at surgery.

## Footnotes

*   **Competing interests:** None.

*   **Patient consent:** Patient/guardian consent was obtained for publication

## REFERENCES

1.  Paulsen F, Tillmann B, Christofides C, et al. Curving and looping of the internal carotid artery in relation to the pharynx:frequency, embryology and clinical implications. J Anat 2000; 197: 373–81.
    
    [CrossRef](http://casereports.bmj.com/lookup/external-ref?access_num=10.1046/j.1469-7580.2000.19730373.x&link_type=DOI) 
    
    [PubMed](http://casereports.bmj.com/lookup/external-ref?access_num=11117624&link_type=MED&atom=%2Fcasereports%2F2009%2Fbcr.07.2008.0362.atom) 

2.  La Barbera G, La Marca G, Martino A, et al. Kinking, coiling, and tortuosity of extracranial internal carotid artery: is it the effect of a metaplasia? Surg Radiol Anat 2006; 28: 573–80.
    
    [CrossRef](http://casereports.bmj.com/lookup/external-ref?access_num=10.1007/s00276-006-0149-1&link_type=DOI) 
    
    [PubMed](http://casereports.bmj.com/lookup/external-ref?access_num=17119858&link_type=MED&atom=%2Fcasereports%2F2009%2Fbcr.07.2008.0362.atom) 
    
    [Web of Science](http://casereports.bmj.com/lookup/external-ref?access_num=000242660900007&link_type=ISI) 

3.  Govindarajan R, Lewin J. Case twenty seven – abnormal tortuosity of internal carotid artery. University Hospitals of Cleveland - department of radiology. Neuroradiology imaging teaching files 2008 May.