Unilateral Aplasia versus Bilateral Aplasia of the Vertebral Artery: A Review of Associated Abnormalities

Table 4

Sixteen (16/46) literature cases of total aplasia of the left vertebral artery (VA) and hypoplasia of the right VA.

Number	Gender/age; reference	Initial symptoms or reasons of research	Left VA aplasia
			Associated vascular aplasia	Associated persistent CVBA and/or other vascular abnormalities
			Other arteries and/or veins	Type of persistent CVBA; (vascular source)	Other variants and/or abnormalities	Diagnosed pathology
(1)	F/0; [77]	Stillborn		Left PPHA; (ICA)	Hypoplastics right VA/left A1 and PCoA
(2)	M/14; [47]	Headache/nausea/slight neck stiffness	Left PCoA	Left PPIA (ICA)	Hypoplastic right VA terminated as the PICA; Low left CCA bifurcation; Accessory right MCA	SAH
(3)	M/28; [55]	Cavernous hemangioma in the skin of the forehead		Left PPHA; (ICA)	Hypoplastic right VA; Dilatation of Galen’s vein
(4)	F/43; [45]	Headache		Left PPIA (ICA)	Hypoplastic right VA	Aneurysm of the left PICA; SAH/IVH
(5)	M/51; [76]	Loss of consciousness		Left PPHA; (ICA)	Hypoplastic right VA
(6)	M/52; [75]	Right hemiparesis/aphasia	Left AICA and PCoA	Left PPHA (ICA)	Hypoplastic right VA; Left PICA and ASA of PPHA origin; Ectatic left CCA; Dolicho-left ICA; BT-left CCA common trunk
(7)	F/54; [52]	Headache/weakness of the right lower limb	Bilateral PCoAs	Left PPHA; (ICA)	Hypoplastic right VA	Aneurysms of the right ACA and PPHA–BA junction
(8)	F/55; [68]	Coma		Left PPIA (ICA)	Hypoplastic right VA	Calcified atheromatous plaques in both carotid systems; Lesions from the level of the mesencephalon to the both thalami
(9)	F/55; [78]	Self-audible left; neck bruit		Left PPHA (CCA)	Hypoplastic right VA	Stenosis of the left CCA, ICA, and PPHA
(10)	M/61; [65]	Speech disorder/left supranuclear; facial palsy	Right ACA	Left PPIA (ICA)	Hypoplastic right VA	Calcified atheromatous plaques in both carotid systems and PPIA. Stenosis of bilateral SAs; Aneurysm of the right SA. Lacunar ischemic changes in basal ganglia
(11)	F/62; [60]	Intermittent diplopia	Left PCoA	Left PPHA; (ICA)	Hypoplastic right VA. BT and left CCA common origin	Irregular lesion of; the left CCA bifurcation and a moderate stenosis; with ulceration of the proximal ICA
(12)	F/63; [70]	Transient right hand weakness/left amaurosis fugax		Left PPIA; (ECA)	Hypoplastic right VA terminated as the PICA	Severe ICA stenosis
(13)	F/65; [79]	Left carotid bruit	Both PCoAs	Left PPHA (ICA)	Hypoplastic right VA terminated as the PICA	Stenosis of; the left PPHA origin
(14)	F/73; [74]	Acute paresis in the left arm	Left PCoA	Left PPHA; (ICA)	Hypoplastic right VA	Bleeding in; the right parietooccipital lobe
(15)	F/78; [66]	Transischemic attacks with right-sided paresis		Left PPIA (ICA)	Hypoplastic right VA did not form the BA	Stenosis of the left CCA bifurcation; Ulcerated plaque extended into the ECA, ICA, and PPIA origin
(16)	M/83; [63]	Cerebral infarction	Bilateral PCoAs	Left PPIA; (ECA); Lateral type of the left PPTA (ICA–C3 part)	Hypoplastic right VA supplied only ipsilateral PICA; Distal branch of the left OA of PPIA origin

Cases according to age are listed; number “0” for stillborn status is used; other Arabian numbers indicate age in years; CVBA, carotid-vertebrobasilar anastomosis; F, female; PPHA, persistent primitive hypoglossal artery; ICA, internal carotid artery; A1, precommunicating part of the anterior cerebral artery; PCoA, posterior communicating artery; M, male; PPIA, persistent proatlantal intersegmental artery (independently of its subtype); PICA, posterior inferior cerebellar artery; CCA, common carotid artery; MCA, middle cerebral artery; SAH, subarachnoid hemorrhage; IVH, intraventricular hemorrhage; AICA, anterior inferior cerebellar artery; ASA, anterior spinal artery; BT, brachiocephalic trunk; ACA, anterior cerebral artery; BA, basilar artery; SA, subclavian artery; ECA, external carotid artery; PPTA, persistent primitive trigeminal artery; C3, cavernous part of the internal carotid artery; OA, occipital artery.