Bulbar Compression by an Ectatic Vertebral Artery: A Novel Neurovascular Construct Relieved by Microsurgical Decompression

Abstract

Brainstem dysfunction caused by a tortuous ectatic vertebral artery might be less uncommon than expected. It should be considered a new distinct clinical entity, the real incidence of which needs to be carefully evaluated by an appropriate diagnostic protocol, which includes primarily magnetic resonance imaging with specific three-dimensional sequences. Awareness of this condition is necessary to ensure the appropriate treatment. Surgical microvascular decompression seems very effective.

Vertebrobasilar dolichoectasia as a cause of trigeminal neuralgia: the role of microvascular decompression. Case report

“…When cranial nerve dysfunction, especially trigeminal neuralgia, is caused by anomalies of cali b e r, length, and tortuosity of the vert e b ro b a s i l a r a rteries, alternative techniques, such as re p o s i t i o ning of the tortuous vert e b robasilar art e ry by pulling it toward the nearby dura mater 2 0 and encirc l i n g method of trigeminal nerve decompre s s i o n 1 4 h a v e been re p o rted re c e n t l y. In the present case case, the authors thought that these techniques would not bring advantages over the microvascular decompre ssion 20 .…”

Brainstem compression syndrome caused by vertebrobasilar dolichoectasia: microvascular repositioning technique

“…Some authors suggest that VBD may be a congenital vasculopathy of the elastic layer of the arterial wall, and may be cause of posterior circulation dysfunction independent of atherosclerosis disease affecting the intimal layer 1,3,10 . Others suggest a hypothesis that try to explain the posterior circulation ischaemia by the induced atherosclerosis in dolichoectatic arteries at the regions of maximum angulation [10][11][12] .…”

“…Janneta et al, in experimental studies in 1985, induced hypertension values with a balloon model and found out the relationship between pulsatile brain stem compression as a possible cause of essential neurogenic hypertension 20 . In some rare circumstances, compression of the medulla oblongata by an aberrant vessel may also cause sleep disordered breathing such as central or obstructive apnea 3 .…”

“…In the surgical strategy of this condition, it is not sufficient to achieve decompression only by insertion of prosthesis between the vessel and the brainstem, because the size and stiffness of the dilated artery makes standard microsurgery dificult. Moreover, the overall size of the ectatic vessel and its increased pulsatility do not allow an effective separating action by the prosthesis 3 . Besides that, an increased neural compression may be expected with the placement of prosthesis in the conflict area in such condition.…”

“…It accounts for approximately 3 to 5% of all cerebellopontine mass lesions. A variety of clinical syndromes have been related due to pulsatile compression by the aberrant vessel: cerebellar dysfunction, hydrocephalus, ischemic stroke, transient or permanent motor deficits, central sleep apnea, trigeminal neuralgia, as well as brain stem compression syndrome 1,3,4 . Microvascular decompression surgery was introduced in the 1960s and was initially used to treat trigeminal neuralgia, hemifacial spasm and glossopharyngeal neuralgia 5 .…”