A review of the diagnosis and management of vertebral basilar (posterior) circulation disease

Abstract

We have reviewed the English literature published in the last 70 years on Diseases of the Vertebral Basilar Circulation, or Posterior Circulation Disease (PCD). We have found that errors have been made in the conduct and interpretation of these studies that have led to incorrect approaches to the management of PCD. Because of the difficulty in evaluating the PC, the management of PCD has been incorrectly applied from anterior circulation disease (ACD) experience to PCD. PCD is a common form of stroke affecting 20-40% patients with stroke. Yet, the evidence is strong that the Anterior Circulation (AC) and Posterior Circulations (PC) differ in their pathology, in their clinical presentations, in the rapidity of development of symptoms, in optimal imaging methods, and in available treatments.There appears to be two categories of patients who present with PCD. The first, acute basilar artery occlusion has a more rapid onset. The diagnosis must be made quickly and if imaging proves a diagnosis of Basilar Artery Occlusion (BAO), the treatment of choice is Interventional removal of the basilar artery thrombosis or embolus. The second category of PCD and the most commonly seen PCD disease process presents with non-specific symptoms and early warnings of PCD that now can be related to ischemic events in the entire PC vessels. These warning symptoms and signs occur much earlier than those in the AC.IA angiography is still the gold standard of diagnosis and is superior in definition to MR and CT angiography which are commonly used as a convenient screening imaging tool to evaluate PCD but are both inferior to IA angiography in definition for lesions below 3-4 mm. In at least two reported studies 7T MR angiography appears superior to other imaging modalities and will become the gold standard of imaging of PCD in the future. Medical treatments applied to the ACD have not been proven of value in specific forms of PCD. Interventional therapy was promising but of unproven value in Randomized Controlled Trials (RCT) except for the treatment of Basilar Artery Occlusion (BAO).Surgical revascularization has been proved to be highly successful in patients, who are refractory to medical therapy. These studies have been ignored by the scientific community basically because of an incorrect interpretation of the flawed EC-IC Bypass Trial in 1985 as applying to all stroke patients. Moreover, the EC-IC Bypass Study did not include PCD patients in their study population, but the study results were extrapolated to patients with PCD without any scientific basis. This experience led clinicians to an incorrect bias that surgical treatments are of no value in PCD. Thus, incorrectly, surgical treatments of PCD have not been considered among the therapeutic possibilities for PCD.QMRA is a new quantitative MR technique that measures specific blood flow in extra and intracranial vessels. QMRA has been used to select those patients who may benefit from medical, or interventional, or surgical treatment for PCD based on flow determinations with a high ...

Unusual presentation of basilar artery thrombosis

“…The overall good outcome with no or mild deficit is 20-25%. 2) Unenhanced CT is relatively insensitive in detecting early signs of posterior circulation ischemia, as seen in our patient with normal initial CT of the brain. This is due to imaging artifacts that limit its usefulness.…”

“…Although better, the mortality rate has remained high because of recurrent thrombosis, hemorrhagic complications, and irreversibility of the stroke itself. The overall good outcome with no or mild deficit is 20-25% [ 2 ].…”

A Rare Case of Type II Odontoid Fracture With Bilateral Vertebral Arteries Occlusion Without Neurological Deficits

“…Despite the superiority of IA angiography in detecting PCDs, MR and CT angiography are convenient screening imaging tool to evaluate PCDs. 17 Bilateral vertebral artery occlusion is common with neurological symptoms, though neurological symptoms did not exist in this case of study. In this case, the importance of clarifying acute vascular events due to spine trauma is the key to diagnosing this occlusion in an emergency department.…”

Combined native magnetic resonance angiography, flow-quantifying, and perfusion-imaging for impending second-stroke assessment

“…Those with low flows was amenable to aggressive medical, interventional or surgical treatment to regain flow and then resumed a post-treatment stroke-free course that paralleled those who had normal posterior circulation blood flows (15,19). These studies represent a major advance in the diagnosis and treatment of atherosclerotic vertebrobasilar disease, as patients with flow deficits are separated into categories in which various therapies can be studied (20). Moreover, in Figure 1 Phase contrast and flow rate.…”