Transient perivascular inflammation of the carotid artery superimposed on carotid atherosclerotic plaque, recurring at the mid-common carotid artery: a case report

Transient perivascular inflammation of the carotid artery (TIPIC) syndrome is a rare acute cervical pain syndrome of unclear etiology and pathogenesis. Its main symptom is unilateral neck pain, typically localized to the distal common carotid artery bifurcation, and symptoms usually last for less than two weeks. The syndrome is self-limiting and non-steroidal anti-inflammatory drugs (NSAIDs) are the mainstay of treatment. We report a case of a 37-year-old woman presenting with persistent bilateral neck pain radiating to the parotid region, in whom imaging confirmed a unilateral lesion of the left common carotid artery (bilateral symptoms with unilateral TIPIC). The patient experienced two separate episodes of acute pain at the same site (mid-portion of the left common carotid artery) within six months, in the setting of a pre-existing plaque at that location. Imaging examinations, including ultrasonography, plain magnetic resonance imaging (MRI), and high-resolution vessel wall MRI, clearly demonstrated perivascular inflammation at the mid-portion of the left common carotid artery, rather than thickening of the underlying plaque. Following a 2-week course of NSAID treatment, resolution of the perivascular lesion was observed after both episodes. Based on the clinical features, imaging findings, and established diagnostic criteria, a diagnosis of TIPIC syndrome was confirmed. Because of its transient clinical course and moderate pain intensity, this is often misdiagnosed, even by neurologists. This case is distinguished by two features: the lesion occurred in the mid-portion of the common carotid artery rather than the more common distal bifurcation, and it was superimposed on a pre-existing carotid atherosclerotic plaque. The atypical localization and plaque association broaden the recognized phenotypic spectrum of this rare condition.