Basilar artery ectasia. (An unusual cause of a cerebello-pontine lesion and hemifacial spasm)

Non-atherosclerotic fusiform cerebral aneurysms

BACKGROUND

Fusiform cerebral aneurysms are dilatations of the entire circumference of a segment of cerebral artery, usually considered due to atherosclerosis in adults. They are relatively thick-walled and elongated, causing neural compression or ischemia when discovered. We have noted a subset of fusiform cerebral aneurysms that vary from this common description.

PATIENTS

Out of a series of 472 intracranial aneurysms treated over 11 years, 11 patients between the ages 16 and 67 years (mean age 37) were identified who had discrete fusiform aneurysms unassociated with generalized cerebral atherosclerosis, connective tissue disorder or inflammation. Three presented with hemorrhage, six with neural compression by the aneurysm and two were discovered incidentally.

RESULTS

Nine aneurysms were located in the posterior circulation, the other two in the intracranial carotid artery. Their mean length and width were 16.3 and 11 mm, respectively. Three aneurysms contained thrombus. The eight aneurysms that were exposed surgically were partly or substantially thin-walled with normal appearing parent arteries. Eight were treated with proximal occlusion and three were circumferentially "wrapped". Parent artery occlusion caused one death and one mild disability and the remaining patients made good recoveries (follow-up 0.5 - 10 years).

CONCLUSIONS

There is a subset of cerebral aneurysms with discrete fusiform morphology, apparently unrelated to cerebral atherosclerosis or systemic connective tissue disease, thin-walled in part or whole, more common in the vertebrobasilar system, and possessing a risk of rupture. Treatments currently available include proximal occlusion or aneurysm wrapping", different approaches than neck-clipping or endovascular coiling of side-wall saccular cerebral aneurysms that leave the parent artery intact.

Anchoring method for hemifacial spasm associated with vertebral artery: technical note

OBJECTIVE

We describe an easy and useful method for treating hemifacial spasm related to the vertebral artery.

METHODS

The technique entails the manufacture of a dural belt harvested from the cerebellar convexity dura and a dural bridge made at the petrous dura combined with the use of an aneurysm clip. The dural belt holds the vertebral artery and is anchored to the dural bridge by fixation with an aneurysm clip after the vertebral artery is transposed to an appropriate position.

RESULTS

The technique proved to be safe and effective in a series of six patients with hemifacial spasm who were followed up for a period of 2 months to more than 10 years after surgery. All patients were affected on the left side. Multiple offending arteries were present in three cases. Hemifacial spasm completely disappeared in all patients.

CONCLUSION

This method represents a feasible option for the treatment of hemifacial spasm caused by a tortuous, elongated, or enlarged vertebral artery.

Giant fusiform aneurysm presenting as fatal basilar artery occlusion

Fusiform aneurysms are often asymptomatic, and therefore their actual incidence is unknown. Ischemic stroke has been linked to dislodgment of small thrombi formed inside the aneurysm but is uncommon. This article describes two patients with rapidly fatal infarction in the entire pons, both cerebellar hemispheres, thalamus, and occipital lobes, findings consistent with occlusion of the vertebrobasilar artery complex. In both patients, autopsies revealed a giant fusiform aneurysm of the basilar artery.

Characteristics and surgical treatment of dolichoectatic and fusiform aneurysms

Dolichoectatic and fusiform aneurysms represent a small subset of cerebral aneurysms and are often among the most difficult to treat. A consecutive series of 40 patients with 41 of these two types of aneurysms is presented, including their clinical characteristics and surgical treatments. Common to all aneurysms was the pathological involvement of a length of blood vessel with separate inflow and outflow sites (nonsaccular). However, dolichoectatic aneurysms have markedly different symptoms and surgical treatments depending on their location in either the anterior or posterior circulation. Anterior circulation aneurysms involved the petrous internal carotid artery (ICA) in one, the supraclinoid ICA in three, the middle cerebral artery in 13, and the anterior cerebral artery in four patients. Posterior circulation aneurysms involved the basilar artery in 13, the vertebral artery in six, and the posterior inferior cerebellar artery in one patient. Various surgical procedures were performed, including direct clipping, trapping with bypass, proximal occlusion, resection with reanastomosis, transposition, aneurysmorrhaphy with thrombectomy, and wrapping. There was no surgical mortality in the patient series, and treatment was effective in many patients. Overall, outcome at late follow up was good (Glasgow Outcome Scale scores 1-2) in 78% of patients. Patients with anterior circulation aneurysms had better outcomes than patients with posterior circulation aneurysms, with good outcomes in 90% and 65% of the cases, respectively. Dolichoectatic and giant serpentine aneurysms may develop from smaller fusiform aneurysms and represent a spectrum of the same pathological entity. Arterial dissection may also play a role in the initial development of these aneurysms.

Microvascular sling decompression for trigeminal neuralgia secondary to ectatic vertebrobasilar compression. Case report

A patient with trigeminal neuralgia caused by a tortuous and ectatic vertebrobasilar artery is presented. He was treated with microvascular decompression using a fine silicone sling sutured to the dura over the petrous pyramid. The technical details are described.

Transcallosal, transventricular approach to a basilar apex aneurysm

A new approach to the basilar apex in a patient with a megadolichobasilar anomaly and an abnormally rostral basilar apex aneurysm is described. The details of the surgical approach and the advantages and limitations of this transcallosal, interseptal approach are described.

Hemifacial spasm: a review

Hemifacial spasm can be diagnosed by observation and clinical history. It is thought to arise primarily from compression of the facial nerve at the pons, usually by an adjacent artery. Although many approaches to treatment have been tried, the most effective is microvascular decompression of the facial nerve at the pons. That operation has well-recognized risks, including ipsilateral deafness. The latter complication ordinarily can be avoided by the use of intraoperative monitoring of auditory evoked potentials.

Multiple neurological lesions due to vertebrobasilar dolichoectasia

Four cases which presented with multiple neurological signs caused by vertebrobasilar dolichoectasia are reported. The pathology was revealed by CT, MRI and angiograms. In one case, hemifacial spasm and other neurological deficits were cured by microvascular facial nerve decompression. The literature on the subject is reviewed.

Fusiform basilar aneurysm as a cause of embolic stroke

Giant fusiform basilar aneurysms (dolicho-ectatic basilar anomalies) are rare and have not previously been reported to cause embolic infarction in territory distal to the aneurysm. They most commonly present as posterior fossa mass lesions with brainstem compression and cranial neuropathies. Originally considered atherosclerotic in etiology, recent authors feel that they may represent a unique arteriopathy characterized by loss of elastin in the vessel wall. We report a case which presented solely as an occipital lobe infarction. To our knowledge, this is the first case in which a fusiform basilar aneurysm presented with an embolic infarction as its only manifestation.

Fusiform basilar aneurysm simulating carotid transient ischemic attacks

Fusiform aneurysms of the basilar artery are extremely unusual. Most show signs of a posterior fossa mass. One case is reported which presented with recurrent transient ischemic attacks suggesting carotid vascular disease. Failure of an appropriate endarterectomy to relieve the symptoms, and later brain stem infarction, led to the correct diagnosis. Whenever recurrent or new symptoms appear following carotid vascular surgery, other diagnoses must be considered.

[Megadolichobasilar anomaly: apropos of 5 cases diagnosed angiographically]

After brief considerations on the symptomatology and ethiopathogeny of megadolichobasilar, five cases of this vascular anomaly are presented. Agreeing with the majority of the papers on the subject, the age of the patients was between the fourth and the sixth decades, all of them presenting arterial hypertension of long duration and advanced atherosclerosis; the neurological findings were varied, having in common the fact of an abrupt (ictal) beggining. The angiographic study of the vertebrobasilar system was basic in the diagnosis in every case.

Facial spasm

There are many varieties of abnormal facial movement. This paper discusses hemifacial spasm and blepharospasm in particular. A technique found useful for the symptomatic relief of idiopathic hemifacial spasm is described, and experience with its use on 15 patients also described. Experiences in the operative treatment of 6 patients with essential blepharospasm are recounted.