A 43-year-old Caucasian man was admitted to the emergency department of our hospital for headache associated with weakness of the left limbs. He had no medical history, he denied even slight trauma of the neck, and his only cardiovascular risk factor was tobacco smoking for 10 years. Neurological examination revealed verbal aphasia and left hemiparesis.\nDuring CT angiography (TK–64-row MDCT scanner, LightSpeed VCT, GE, Waukesha, WI) of the neck and head, segmental dissections of the right internal carotid artery (ICA) at the level of the cranial basis were discovered (Fig. a). The lumen of the ICA was decreased to 4 × 2.5 mm (60 % of normal flow). Cerebral CT showed a recent infarction involving the medial part of the right temporal lobe and deep structures of the right hemisphere including the thalamus, the genu and the posterior limb of the internal capsule (Fig. b).\nCT angiography of the neck and head also showed a duplication of the left vertebral artery (LVA) with two origins, both from the left subclavian artery (Figs. , ). The duplicated segments were fused at level of the C5–6 vertebrae into a single vertebral artery, which then entered the transverse foramen of C5 (Fig. ). All measurements were taken on an Advantage Workstation (GE).\nThe first LVA originated from the left subclavian artery at a distance of 7 mm from the aortic arch. It measured 2.9 and 2.8 mm in diameter at the points of origin and just before fusion, respectively (Fig. ). The course of the artery was 101 mm. The second LVA arose from the left subclavian artery 37 mm distal to the first (44 mm from the aortic arch). It measured 2.4 and 2.2 mm in diameter at the points of origin and just before fusion, respectively (Fig. ), and its course was 89 mm. Both vertebral arteries possessed a regular lumen. The diameter of the LVA after fusion was 3.3 mm (at level C5–6) (Fig. ).\nThe right VA arose as the first branch from the left subclavian artery, 43 mm from the aortic arch. Its course was normal. The diameters of the right VA were 4 mm at the points of origin and 3.8 mm at the C5–C6 vertebrae (Fig. ). Both thyrocervical trunks were seen to originate separately from the subclavian arteries.\nAdditionally, complementary but independent to CT angiography Doppler Sonography B-flow mode (Vivid 7 Pro, GE) of the vertebral arteries also revealed a duplicated LVA (Fig. ).\nAfter all procedures were completed, Ehlers–Danlos syndrome type IV was diagnosed.
A 36 year-old male with a history of dizziness and suspected cerebrovascular pathology was referred to our center for angiographic evaluation of carotid and vertebral arteries. He underwent multidetector 64-row computed tomography (MDCT) angiography. (GE: Optima660,2011, Tokyo, Japan60). Eighty-five milliliter of nonionic iohexolcontrast (Omnipaque, 350 mg I/ml, GE Healthcare, Shanghai, China) was injected at a rate of 5 ml/s by a power injector through the antecubital vein. The acquired images (slice thickness 0.625 mm) were further analyzed in a work station (GE: AW Volume Share 4) to generate volume-rendered (VR) and maximum intensity projection (MIP) images.\nThe left vertebral artery (LVA) had two separate limbs of origin []. The medial limb (2.2 mm in diameter at its origin) originated directly from the aortic arch in between the origins of left common carotid (LCCA) and left subclavian arteries (LSA) []. The lateral limb (2.4 mm in diameter at its origin) emanated from the LSA in its orthodox position and entered the foramen transversarium of C6 vertebra. Both the limbs united to form a single trunk at C5-C6 interval and the single trunk (3.2 mm in diameter) then entered C5 transverse foramen [Figures and ]. Both the limbs of the right vertebral artery (RVA) originated from the right subclavian artery (RSA) []. The medial limb (3.9 mm in diameter at its origin) originated from its orthodox position, whereas the lateral limb (2.4 mm in diameter at its origin) arose more posteriorly close to the origin of thyrocervical trunk. The lateral limb entered the C6 transverse foramen, but the medial limb entered the carotid space lying posteromedial to right common carotid artery (CCA) []. At the interval between the C4 and C5 vertebrae, both the limbs fused to form a single trunk (4.4 mm in diameter) which entered the C4 transverse foramen [Figures and ]. Further distal course of both vertebral arteries was normal and no cerebrovascular pathology could be detected.