Giant Cell Arteritis with Bilateral Intracranial V4 Vertebral Artery Stenosis

A 71-year-old man presented with recurrent episodes of vertigo, dizziness, double vision, and gait disorder, each lasting a few minutes, for 3 weeks prior to admission. The patient had a history of giant cell arteritis (GCA) that had been diagnosed 3 months before this presentation by temporal artery biopsy. At the time he had complained of right-sided temporal headache with jaw claudication, masseter pain, and abnormal fatigue. Laboratory findings revealed an increased erythrocyte sedimentation rate (ESR) (75 mm/h, Westergren) and an elevated C-reactive protein (CRP) of 57 mg/L (normal <5 mg/L). He had been treated with high-dose steroids for 3 weeks. This was subsequently reduced to a daily dose of 7.5 mg prednisolone. He had known vascular risk factors of arterial hypertension and a positive family history of stroke.

On admission, his neurologic examination was normal. He had no complaints suggestive of GCA, in particular any headaches or jaw claudication. The ESR was normal during treatment, but CRP levels were still slightly raised (19 mg/L).

Recurrent transient ischemic attacks (TIAs) in the vertebrobasilar territory due to bilateral VA stenosis at the V3–V4 junction of unknown origin.

• Were there signs of vasculitis or atherosclerosis in the brain-supplying arteries or in the external carotid artery (ECA), superior temporal artery (STeA), or STeA branches?
  
• What was the degree of the bilateral distal VA stenosis?

Extracranial Duplex Sonography

The neurologic symptoms of the patient were evaluated as recurrent vertebrobasilar TIAs probably of hemo dynamic origin and attributed to the bilateral distal VA stenoses. Their etiology was thought to be either of atherosclerotic origin or caused by the known GCA. The location of the stenoses at the level of the dural passage and the symmetric pattern seemed atypical for a classic atherosclerosis. The findings were more suggestive of arteritis with the STeA insonation demonstrating the dark halo sign and with the raised CRP. The dose of prednisolone was therefore increased to 30 mg/day.

Extracranial Duplex Sonography

Recurrent vertebrobasilar TIAs of hemodynamic origin caused by bilateral VA stenosis starting at the V3–V4 junction with extension to the proximal V4 segment and secondary occlusion of the right V4-VA below the PICA origin. GCA seemed to be the most likely etiology.

Clinical Aspects

Here we discuss a patient with recurrent TIAs in the posterior circulation. This evaluation was based on the type and temporal pattern of symptoms lasting for minutes only. The combination of transient vertigo, diplopia, and gait disturbances was rather suggestive of impaired brainstem perfusion of hemodynamic origin. This assumption was confirmed by the radiologic findings of bilateral VA stenoses starting at the level of the V3–V4 junction with extension to the proximal V4 segments.

Three months prior to the reported neurologic symptoms, GCA was diagnosed and histologically confirmed in one temporal artery. GCA is an autoimmune vasculitis of unknown origin that typically occurs in medium and large arteries with well-developed wall layers and adventitial vasa vasorum (Weyand and Goronzy 2003). The disease occurs almost exclusively in individuals older than 50 years, with peak incidence at the age of 70–80 years (Gonzalez-Gay et al 2009). The age-adjusted incidence is 24.2/100,000 for women and 8.2/100,000 for men among white northern European populations (Salvarani et al 1995). The incidence is lower in southern European populations and markedly lower in American populations of Asian or African descent. Based on large autopsy studies, the prevalence of GCA is estimated at ~1% (Östberg 1971). The typical histopathologic picture is an inflammatory infiltrate in all three tunicae of the arterial wall with giant cells forming granulomas in the media. Fragmentation of the internal elastic lamina is characteristic, and medial vascular smooth muscle cells are destroyed. Vasculitis leads to luminal occlusion due to intimal hyperplasia and therefore to ischemic complications such as ischemic optic neuropathy. Giant cells are commonly present, and are consequently detected in 60–70% of samples (Lie 1990, Liozon and Catanzano 1982). In up to 100% of cases the STeA, the VA, the OA, the central and posterior ciliary arteries, or a combination of these vessels are affected (Wilkinson and Russell 1972). Vessel wall changes might also be found in other arteries such as external carotid branches (e.g., occipital and facial), subclavian, axillary, brachial, ulnar, radial, femoral, popliteal, posterior tibial, dorsal pedal arteries, and the thoracic aorta (W.A. Schmidt et al 2002a, Weyand et al 2012). Intracranial involvement may also occur but is rare. A small study reported on nine patients with histologically proven temporal arteritis and intracranial vasculitis shown by angiography and/or histology (Salvarani et al 2006). Involvement of the intracranial ICA with symptomatic stenosis and subsequent ischemic events is more frequent, but the intracranial VAs are seldom affected. These reports of intracranial vessel involvement might, however, be falsely low because the options to confidently diagnose intracranial involvement are currently limited. A recent MRI study, using 3-T imaging for the identification of intramural vessel wall changes, detected intradural ICA affection in 10 out of 20 patients with GCA (Siemonsen et al 2015). The typical predominantly extracranial vascular involvement is in part explained by the inflammation being confined to elastic fibers. As intracranial arteries have less elastic fiber in the media, lack an external membrane, and have a rather small internal membrane, they are less frequently involved. Inflammation of the extracranial VA ceases abruptly no more than a few millimeters after it perforates the dura mater. If present, a symmetric involvement of the VA is common in GCA (Crompton 1959, Wilkinson and Russell 1972).