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Page 6 of 9 Abdelhaliem et al. Vessel Plus 2020;4:31 I http://dx.doi.org/10.20517/2574-1209.2020.13

CAROTID ENDARTERECTOMY AN OLD APPROACH IN AN ENDOVASCULAR ERA AND THE
VASCULAR-NEURO-PSYCHIATRIC AXIS
By default, and without any consensus or attributable guidance, it is well-practiced in various
multidisciplinary meetings and known that proximal lesions of carotid artery disease in the neck generally
lend themselves to carotid endarterectomy practicing surgeons, while distal lesions get stratified and treated
by angioplasty and stenting.

For years, intracranial carotid artery stenosis or carotid stenosis in the skull base have been generally
treated using two approaches. One option, an initial balloon occlusion test performed under transcranial
doppler and electroencephalogram monitoring can determine whether indeed the ipsilateral carotid artery
can be sacrificed. If this is the case, one option is to ligate the symptomatic carotid artery and therefore
arrest the turbulent flow. A second further option is to dilate and then stent the intracranial portion of the
[5]
carotid artery, thereby resulting in a loss of arterial pulsatile tinnitus . From these practices and reported
experiences, more than 70% of patients with carotid stenosis-related tinnitus have immediate amelioration
[5]
and relief of tinnitus . Long-term and longitudinal studies correlating survivability and amelioration of
symptoms are lagging.

Moreover, functional status and cognitive impact of these approaches are yet to be verified and studied in
an unbiased format. As such, interventional as well as non-interventional medical procedures including
carotid artery recanalization, appropriate pharmacological therapy and lifestyle modifications that are used
to maintain blood flow in cerebral small vessels, are not well documented in any coherent evidence-based
approach. This adds to the confounding gap in the literature and strictly limits our practice to surgeon-
oriented and not patient-centred care. It is interesting to note that tinnitus attributable to common carotid
[25]
artery stenosis at its bifurcation has been historically treated by ligation or carotid endarterectomy .
However, curing this entity by endovascular stent angioplasty has received very little attention in the
literature. As such, the heterogeneity of reporting and the lack of informal evidence of best medical practice
reliability of results are questioned.

The advent but lack of availability of complex magnetic resonance imaging, in particular a combination
of dynamic contrast-enhanced magnetic resonance imaging (MRI), dynamic susceptibility contrast MRI
and blood oxygen level-dependent imaging MRI should be able to offer wide-ranging information on
the effects of cerebral microcirculation on functional brain status and fluctuations of blood-brain barrier
permeability. However, those modalities amongst others would not be in a position to add to studies with
the concomitant neuropsychological assessment of patients with the carotid disease and post-tinnitus
correction.

Recent advances leading to a new generation of stents has prompted clinicians to consider performing
stent-assisted angioplasty as an alternative approach to angioplasty alone for intracranial stenosis [26,27] .

Cerebral blood flow, which can undergo assessment during computed tomography perfusion (CTP)
examinations, improves after internal carotid artery stenting [28-30] . However, two further important CTP-
derived variables, blood-brain barrier permeability and mean transit time, are far less recognised in both
the research and diagnosis of internal carotid stenosis.

Internal carotid artery stenosis-related brain hypoperfusion is generally associated with neurological,
psychiatric, psychological and somatic deficits which can manifest with different variants of symptoms
and clinical signs, including tinnitus. This can potentiate ill effect on health-related quality of life. To this
effect, various studies have demonstrated that internal carotid stenosis without transient ischemic episodes