[The role of duplex scanning in diagnosing extravasal compression of vertebral arteries in degenerative diseases of the cervical part of the spine]

The method of duplex scanning was used in examination of 210 patients with degenerative-dystrophic diseases of the cervical part of the spine. It allows quantitative and qualitative assessment of the local and systemic hemodynamic value of extravasal compression of vertebral arteries. Local hemodynamic shifts in the area of extravasal influences on the artery were detected in 72.9% of the patients: decreased indices of blood flow and increased indices of peripheral resistance proximal to the compression zone, growing blood velocity in the area of the artery course deformity, in the place of its lumen constriction, decreased blood flow indices and indices of peripheral resistance distally to the compression zone. The assessment of blood flow in the vertebral arteries allows determination of the strategy of treatment of patients with degenerative-dystrophic diseases of the cervical part of the spine.

Trigemino-autonomic headache related to Gasperini syndrome

We report the association of ipsilateral trigemino-autonomic headache to a case of right-sided nuclear facial and abducens palsy (Gasperini syndrome), ipsilateral hypacusis and right hemiataxia, caused by the occlusion of the right anterior inferior cerebellar artery. Short-lasting attacks of mild to moderate ipsilateral fronto-periorbital head pain, accompanied by lacrimation and mild conjunctival injection during more severe attacks, were present from the onset of symptoms, with a gradual worsening over the next few months and remitting during naproxen therapy. Magnetic resonance imaging showed an infarct in the right cerebellar peduncle, extending toward the pontine tegmentum, also involving the ipsilateral spinal trigeminal nucleus and tract and the trigeminal entry zone. Gasperini syndrome may be accompanied by ipsilateral trigemino-autonomic head pain.

The effect of the sildenafil citrate on cerebral vasospasm and apoptosis following experimental subarachnoid hemorrhage in rats

AIM

The therapeutic effect of sildenafil citrate on cerebral vasospasm after experimental subarachnoid hemorrhage (SAH) was studied in a rat model.

METHODS

We used four groups of seven rats were as follows: no SAH, no treatment; SAH only; SAH plus 2 days of peroral sildenafil citrate 5mg/kg treatment and SAH plus 2 days of peroral sildenafil citrate 15 mg/kg treatment. Three different parameters were evaluated including the diameter of the basilar artery, the level of lipid peroxidation and the degree of the apoptosis 48 hours following SAH.

RESULTS

The results showed that sildenafil citrate attenuated SAH-induced cerebral vasospasm in the treatment groups in terms of the diameter of the basilar artery and lipid peroxidation in the two treatment groups, but there was no difference in terms of the level of apoptosis.

CONCLUSION

This study indicates that further research on the therapeutic effect of sildenafil citrate can be combined with the use of any apoptosis-blocking agent for the treatment of cerebral vasospasm following experimental subarachnoid hemorrhage.

Long-term results of endovascular therapy for proximal subclavian arterial obstructive lesions

BACKGROUND

Endovascular therapy is a treatment option for localized occlusion of the subclavian artery. In this report the long-term experience with 59 patients is presented.

METHODS

Between June 1998 and September 2008, we used endovascular therapy to treat 61 subclavian arterial obstructive lesions in 59 patients (46 males and 13 females, 34 - 82 years of age with a mean age (61.9 + or - 11.0) years). Twenty patients (34%) had clinical symptoms due to vertebrobasilar insufficiency, 26 (44%) had disabling arm ischemia, and 13 (22%) had both symptoms. We performed all procedures under local anesthesia. The approaches were from the femoral artery (n = 47), brachial artery (n = 1, involving bilateral subclavian disease) or both (n = 11). Sixty stents were implanted. All patients were followed-up at 1, 3, 6, and 12 months post-procedure, and annually thereafter.

RESULTS

We achieved technical success in 58 (95.1%) arteries, all of which were stented. There were three technical failures; two were due to the inability to cross over an occlusion, necessitating the switch to an axillo-axillary bypass, and the third was due to shock after digital subtraction angiography and prior to stenting. Arterial stenosis pre- and post-stenting was (83.6 + or - 10.8)% and (2.5 + or - 12.5)% (P < 0.01). Clinical success was achieved in 55 of the 59 patients (93.4%). Of the four clinical failures, three were technical and the remaining patient had a stent thrombosis. Systolic blood pressure difference between the two brachial arteries was (44.7 + or - 18.5) vs. (2.2 + or - 3.9) mmHg (P < 0.01). Primary patency was 98% at 12 months, 93% at 24 months, and 82% at 5 years. Five patients were lost to follow-up by 12 months post-stenting. Significant recurrent obstruction developed in five patients with resumption of clinical symptoms. The overall survival rate was 98.2% at 12 months, 89.5% at 24 months, and 84.5% at 5 years.

CONCLUSIONS

Endovascular therapy for proximal subclavian arterial obstructive lesions is effective and successful. This minimally invasive treatment may be the first choice of treatment for proximal subclavical arterial obstructive lesions.

Vertebral artery hypoplasia is associated with a decrease in net vertebral flow volume

The definition and clinical significance of vertebral artery hypoplasia (VAH) remain inconclusive. VAH has been proposed as a predisposing factor of posterior circulation ischemic stroke. The aim of this study was to determine a best cut-off diameter of vertebral artery (VA) for VAH and to investigate if unilateral VAH is associated with a decrease in net vertebral flow volume. Retrospective data of 1000 presumably healthy subjects free of cerebrovascular disease or apparent carotid atherosclerosis were analysed. We found that a VA diameter </=2.5mm is an ideal value to define VAH. The flow volume of the identified hypoplastic VA was remarkably low and the contralateral VA had only a slightly increased compensatory flow volume. The net VA flow volumes remained significantly and markedly lower in subjects with unilateral VAH (140.7+/-46.2mL/min) than those in subjects without VAH (190.1+/-54.5mL/min, p<0.001). Flow volume insufficiency of VA (defined as a net VA flow volume less than 100mL/min) occurred more frequently in individuals with VAH than in those without VAH (22.1% vs. 2.4%, p<0.001). Our study suggested that asymptomatic subjects with VAH had a significantly lower net VA flow volume and a higher frequency of VA flow insufficiency than the control group. (E-mail: hhhu@vghtpe.gov.tw).

Neurovascular compression in painful tic convulsif

This article describes the case of a 67-year-old woman who presented with a typical left hemifacial spasm of 8-month duration. After 2 months, she experienced lacinating and sharp shock-like pain in the left side of her face affecting the V1 and V2 territories and a discrete attenuation of nauseous reflex on the left side. CT angiography and MRI revealed significant compression of left cranial nerves V, VII, VIII, IX and X by a giant and tortuous vertebro-basilar arterial complex. This case illustrates the nonlinearity of the relationship between the presence of the stressor factor and the actual manifestation of the disease.

Basilar artery steno-occlusive disease is associated with structural changes in the left ventricle

OBJECTIVES

Structural changes in the extracranial carotid artery are associated with an increase in left ventricular (LV) mass and relative wall thickness. The present study was performed to determine the relation of LV mass index and relative wall thickness to suspected atherosclerotic steno-occlusive disease of the intracranial arteries on magnetic resonance angiography (MRA) in noncardioembolic ischaemic stroke patients.

METHODS

We retrospectively analysed the records of acute ischaemic stroke patients who underwent echocardiography and intracranial MRA. Patients with potential sources of cardioembolism, or known causes of vascular steno-occlusive disease including dissection, vasculitis, and moyamoya disease, were excluded from the study. LV mass indexes and relative wall thicknesses were estimated using echocardiography. Patients were divided into four groups according to their LV mass index and relative wall thickness: concentric LV hypertrophy, eccentric LV hypertrophy, concentric LV remodelling, and normal geometry. MRA was used to evaluate steno-occlusive disease in the basilar artery (BA) and the horizontal portion of the middle cerebral artery.

RESULTS

A total of 212 patients were included, and logistic regression analysis revealed that BA steno-occlusive disease was related to LV relative wall thickness, but not LV mass index. The prevalence of BA disease was significantly higher in the concentric LV hypertrophy group than in the normal geometry group. Steno-occlusive disease of the middle cerebral artery was not closely related to the structural changes in the left ventricle.

CONCLUSION

Increased LV relative wall thickness may be an independent risk factor for BA stenoocclusive disease or may share pathogenic mechanisms with BA disease.

Correlations of arterial hemodynamics with the severity of clinical manifestations of vertebrobasilar insufficiency

A variety of clinical manifestations of vertebrobasilar insufficiency in virtually the same anatomical disorders of the vertebral arteries indicates the multilevel regulation of the cerebral bloodflow aimed at its stabilization and maintenance. The main arteries of the head and peripheral arteries were studied by Doppler ultrasonography in patients with anatomical disorders of vertebral arteries (atherosclerotic, extravasal compressions, congenital abnormalities, etc.). A relationship between the variability of clinical picture of vertebrobasilar insufficiency and the diastolic bloodflow in the large aortic arteries was detected.

Operative nuances of an occipital artery to posterior inferior cerebellar artery bypass

Occipital artery to posterior inferior cerebellar artery bypasses remain an important tool for cerebrovascular neurosurgeons, particularly in the management of complex aneurysms of the posterior inferior cerebellar artery requiring proximal occlusion or trapping. The procedure requires meticulous technique and attention to detail. The authors outline their technique for accomplishing this bypass emphasizing nuances for complication avoidance.

Activation of ERK and JNK MAP kinases in optic nerves of rats exposed to global cerebral ischemia

OBJECTIVES

To determine the influence of global cerebral ischemia on the activation of extracellular-regulated kinases (ERK) and c-Jun N-terminal kinases (JNK) in optic nerves of rats exposed to different reperfusion periods.

MATERIALS AND METHODS

Transient global cerebral ischemia (20-min duration) was induced by the four-vessel occlusion method. After different reperfusion periods (5 and 10 min; 1; 6 and 12 h after ischemia), optic nerves were extracted and ERK and JNK activation signals were determined by Western immunoblot analyses.

RESULTS

The activation signals of ERK and JNK were detected within first 10 min of reperfusion, but striking activation for both enzymes was found 1 h after ischemia. After a transient decrease, the activation of ERK returned to peak level after 12 h of reperfusion in the second wave of kinase activation. In that period, a slight increase of JNK activation was registered.

CONCLUSION

Our results demonstrated for the first time that ERK and JNK were activated in rat optic nerves during early and later periods of reperfusion, suggesting their potential active role in the response of cerebral white matter tissue to ischemic injury.

[Hemifacial spasms and vertebral dolichoectasias]

INTRODUCTION

Hemifacial spasm (HFS) is characterized by chronic twitching or spasm of one side of the face. It affects muscles activated by the facial nerve. HFS is believed to result from irritation of the facial nerve at its exit from the brainstem and most cases are associated with a small vascular loop compression. Rarely it is associated with a vertebral artery dolichoectasia.

CASE REPORTS

We report three cases of HFS whose magnetic resonance imaging and magnetic resonance angiography revealed vertebral dolichoectatic arteries compressing the facial nerve and causing HFS. These cases were selected from the group of patients of the dystonic outpatient clinics, Neurology Department, between April 1st 1998 and December 30th 2007.

CONCLUSIONS

Magnetic resonance imaging and magnetic resonance angiography are essential for the diagnosis of a vertebral dolichoectasia and should be considered the initial screening procedures in the assessment of patients with HFS. The role of these neuroradiologic studies in the diagnosis of HFS is not only to detect the vascular structures running adjacent to the root exit zone that might distort the facial nerve and compress the brain stem around the root exit zone, but also to exclude other causes in a single non-invasive examination.

Compensatory collateral circles in vertebral and carotid artery occlusion

The obstructive disease of the supraaortic trunks has considerable clinical importance. Patients with the same grade of obstruction can display a wide spectrum of symptoms. Apart from the grade, etiology and localization of the obstruction, the presence of collateral circles plays an essential role in the determination of the symptoms. We selected all asymptomatic patients, undergoing a diagnostic investigation with EchoColorDoppler in a period of 13 years, in whom an occlusion of the common carotid artery, of the internal carotid artery or of the vertebral artery was present, and we studied the compensatory collateral circles. We considered 8 subjects affected by common carotid occlusion, 66 subjects with internal carotid occlusion and 24 subjects with vertebral artery occlusion. In the 8 subjects affected by common carotid occlusion, before the bifurcation, the collateral circle was realized by the superior thyroid arteries through the supraisthmic thyroid artery. All of the 66 subjects with internal carotid disease showed collateral circles through the ophthalmic branches and through the communicating arteries. In the 24 subjects with vertebral artery occlusion, the compensatory collateral circle was realized by the cervical, costocervical and occipital branches. In conclusion, the presence of an adequate hemodynamic compensation through a collateral circle represents an important positive prognostic factor and can avoid invasive procedures, thus avoiding possible complications.

[In vivo high-resolution magnetic resonance imaging in severe intracranial stenosis]

OBJECTIVE

To assess the feasibility and clinical value of high-resolution magnetic resonance imaging (HRMRI) in patients with symptomatic severe intracranial stenosis (SSIS).

METHODS

HRMRI wasperformed with a 3.0 T MR scanner on 5 patients with symptomatic middle cerebral (n = 3) or basilar (n = 2) arterial stenosis of > or = 70% confirmed by DSA. Image diagnosis was made on the basis of HRMRI findings of vessel wall at the stenotic segment by 2 neuroradiologists blinded to patient's status.

RESULTS

Three of the five patients were diagnosed to have advanced intracranial atherosclerosis based on the presence of a complex eccentric atherosclerotic plaque containing a large lipid-rich necrotic core with a heterogeneous post-contrast enhancement and with signs of ruptured fibrous cap. Two other patients were likely to suffer from non-atherosclerotic lesion. HRMRI revealed an iso-signal septum in the arterial lumen attaching to the slightly thickened arterial wall that was iso-signal with a homogeneous post-contrast enhancement in one patient and an obviously concentrically thickened arterial wall with hypo-intense signal on T1WI and slightly high signal on T2WI and PDWI and without any post-contrast enhancement in the remaining patient.

CONCLUSIONS

In vivo HRMRI in patients with SSIS is technically feasible. It provides detailed information of intracranial arterial wall at the stenotic segment.

Anterior vertebral artery decompression with an ultrasonic bone curette to treat bow hunter's syndrome

We report a patient with bow hunter's syndrome who was treated by anterior decompression of the vertebral artery (VA) using an ultrasonic bone curette (SONOPET). This 60-year-old man reported almost losing consciousness upon head rotation. Although the right VA appeared normal at the natural head position, upon left head rotation it became completely occluded at the transverse foramen of C2. We performed anterior decompression of the right VA at the axis using a high-speed drill and SONOPET. For anterior decompression of the VA in a deep and narrow operative field, we recommend use of SONOPET, which permits safe, easy bone dissection.

Using vestibular evoked myogenic potentials to localise brainstem lesions. A preliminary report

BACKGROUND

Vestibular Evoked Myogenic Potentials (VEMPs) are saccular responses to acoustic stimuli. They can be recorded from the sternocleidomastoid muscle ipsilaterally to the stimulated ear. Their reflex arc includes the ipsilateral vestibular nuclei.

OBJECTIVE

To determine the usefulness of VEMPs in localising brainstem lesions.

METHODS

We used VEMPs, Blink Reflex (BR) and Brainstem Auditory Evoked Responses (BAERs) to evaluate six patients presenting with acute ischaemic or haemorrhagic brainstem lesions, or basilar dolichoectasia.

RESULTS

MRI in patient one revealed a dorsolateral medullary infarct on the right. VEMP amplitude was reduced ipsilaterally. The R2 BR component was delayed bilaterally upon stimulation of the affected side. Patients two and three had suffered a left lateral lower pontine infarct and a right lateral lower pontine haemorrhage. In patients four and five, MRA revealed dolichoectasia of the basilar artery exerting pressure on the lower lateral pons. VEMP amplitude was reduced ipsilaterally. Patient six had an ischaemic lesion in the right upper lateral pons. The R1, R2i and R2c BR components were delayed ipsilaterally. BAERs waves IV and V were absent on the right. VEMPs were normal.

CONCLUSIONS

VEMPs are affected by lesions of the lateral lower pons and upper medulla. Our results suggest that they may be a useful addition in the localisation of such lesions.

Clinically successful late recanalization of basilar artery occlusion in childhood: What are the odds?

BACKGROUND AND PURPOSE

Acute basilar artery occlusion is an infrequent but potentially fatal cause of stroke, both in adults and children. We present our experience with a 6-year-old child and we investigate the rationality for late treatment of acute basilar occlusion in children.

METHODS

We report the case of a 6-year-old boy with acute basilar artery occlusion presented with a full blown locked-in syndrome, admitted to the endovascular suite 44 h after the stroke onset, and we review all the reported cases of basilar artery occlusions presented with locked-in syndrome in children.

RESULTS

Six hours following admission the basilar artery was partially recanalized by intra-arterial thrombolysis combined with mechanical clot angioplasty. After 12 h, the patient was awake, oriented, his speech function was fully restored and he had only a mild right hemiparesis that recovered completely after a month.

CONCLUSIONS

To our knowledge, this is the first report of complete clinical recovery after delayed (50 h) endovascular recanalization of basilar artery in a child. Intra-arterial thrombolysis combined with cerebral angioplasty, can successfully restore the patency of the basilar artery and the neurologic deficit of children with acute basilar artery occlusion, even after a considerable delay.

Transcranial Doppler ultrasonographic evaluation of vertebral artery hypoplasia and aplasia

BACKGROUND AND PURPOSE

Evaluation of vertebral artery (VA) with transcranial Doppler ultrasonography (TCD) is difficult due to anatomical variations of hypoplasia (HP) or aplasia (AP). TCD findings of HP or AP of VA are rarely known. Comparing with magnetic resonance angiography (MRA), we tried to evaluate characteristic findings of HP or AP of VA using TCD.

METHODS

Consecutive healthy patients who underwent TCD and MRA were included. VA was classified as normal (NL), hypoplasia (HP), and aplasia (AP) according to MRA. TCD parameters of mean flow velocity (MFV), pulsatility index (PI), vertebral/basilar artery flow velocity ratio (VA/BA FVR), and asymmetry index (AI) of VA were compared between three groups.

RESULTS

Four hundred and ten patients were included, and 298 patients (72.7%) were classified as NL, 98 (23.9%) as HP and 14 (3.4%) as AP. MFV, PI and VA/BA FVR of ipsilateral VA were not different between groups. However, MFV of contralateral VA and AI were significantly increased in HP and AP groups (p<0.001). AI was significantly different between the three groups (17.7% and 30.5%, p<0.001). Sensitivity and specificity for HP or AP were 20.5% and 90.9%, if AI over 40% were adopted as diagnostic criteria.

CONCLUSION

MFV of VA should be interpreted with caution for its frequent anatomical variations. Increased MFV of unilateral VA may indicate not only as ipsilateral stenosis, but also as contralateral HP or AP. AI over 40% is specific to predict unilateral HP or AP with clinical correlation.

Treatment of a giant vertebrobasilar artery aneurysm using stent grafts

✓This 65-year-old man presented to the authors' institution reporting neck swelling. Stage IIIA Hodgkin disease was diagnosed, and a computed tomography scan of the neck revealed a vertebrobasilar artery aneurysm. His medical history was significant for subarachnoid hemorrhage and coma 2 years earlier. Subsequent digital subtraction angiography demonstrated a giant fusiform vertebrobasilar junction aneurysm with associated basilar artery (BA) fenestration. Endovascular treatment of the giant aneurysm was performed by left vertebral artery (VA) occlusion and placement of two Jo-stent coronary stent grafts from the right VA to the BA. The postprocedure course was uneventful. Follow-up angiography performed 1 week postoperatively demonstrated complete exclusion of the aneurysm. This unique case is described and a review of the relevant literature is presented.

Cervical vertebral artery variations: an anatomic study

In this article, we present 5 cases of uncommon anomalous vertebral arteries and discuss the possible embryologic etiologies. These cases include a left vertebral artery as the 2nd branch off the left subclavian, a left vertebral artery with 2 origins, a right vertebral artery arising as the last branch off the aorta, a right vertebral artery arising as the 2nd branch off the right subclavian artery, and right vertebral artery with proximal duplication as the 2nd branch off the right subclavian artery.

Artery of Percheron thrombolysis

SUMMARY

A patient with acute top of the basilar syndrome clinically was found to have only a small basilar artery filling defect but complete occlusion of the artery of Percheron. Intra-arterial thrombolysis resulted in favorable neurologic outcome. To our knowledge, this is the only case of angiographically proved and treated artery of Percheron occlusion. The value of this report is that reperfusion of ischemic areas was only achieved when persistent investigation disclosed artery of Percheron occlusion.