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M Ezura

Publications and source records attributed to M Ezura.

At least 19 recordsLinked to original sources
PubMed2006

Subcortical calcification on CT in dural arteriovenous fistula with cortical venous reflux.

We report 3 cases of dural arteriovenous fistula (dAVF) with cortical venous reflux (CVR) presenting calcification in the cortico-medullary junction at the bottom of cerebral sulci on unenhanced CT. This likely results from chronic venous congestion with resulting impaired perfusion of the involved parenchyma. dAVF with CVR, which is known to have poor prognosis without treatment, should be included in the differential diagnosis of subcortical calcification on CT.

Aged↗
PubMed2001

Fusiform aneurysm of the vertebral artery presenting hemifacial spasm treated by intravascular embolization: case report.

BACKGROUND: A rare case of fusiform vertebral artery aneurysm causing hemifacial spasm was successfully treated by intravascular embolization. CASE DESCRIPTION: A 53-year-old man presented with left hemifacial spasm persisting for 2 years. No other clinical symptoms were observed. Vertebral angiography revealed a fusiform aneurysm of the left vertebral artery, and thin-slice spoiled gradient-recalled acquisition magnetic resonance imaging demonstrated the aneurysm compressing the root exit zone of the left facial nerve. The parent artery was occluded together with the aneurysm by intravascular embolization with Guglielmi detachable coils (GDCs). The patient is free of left hemifacial spasm without any complication. CONCLUSION: Hemifacial spasm caused by aneurysms, especially fusiform aneurysms, is quite rare but can be treated by parent artery occlusion and coiling the aneurysm with GDCs.

Cerebral Angiography↗
PubMed2001

Intraaneurysmal embolization of an unruptured basilar tip aneurysm associated with moyamoya disease.

We describe a patient with moyamoya disease associated with an unruptured basilar tip aneurysm which was treated by endovascular embolization using Guglielmi detachable coils (GDCs). A 53-year-old man presented with left hemiparesis persisting for 3 mon ths before admission. Cerebral angiography revealed occlusion of the bilateral middle cerebral arteries and the left anterior cerebral artery, stenosis of the right anterior cerebral artery, and basal moyamoya vessels. In addition, a saccular small aneurysm was seen at the top of the basilar artery. The aneurysm was completely embolized by intraaneurysmal GDCs. Direct surgical clipping is often selected for the treatment of posterior fossa aneurysms in moyamoya disease. However, complete clipping is usually difficult due to the difficulties in operative technique associated with moyamoya disease. We suggest that the endovascular treatment using GDCs is comparatively safe and effective for the treatment of surgically difficult aneurysms in patients with moyamoya disease.

Cerebral Angiography↗
PubMed2001

Brain single-photon emission CT studies using 99mTc-HMPAO and 99mTc-ECD early after recanalization by local intraarterial thrombolysis in patients with acute embolic middle cerebral artery occlusion.

BACKGROUND AND PURPOSE: The brain distribution of 9mTc-hexamethylpropyleneamine oxime (HMPAO) correlates with regional brain perfusion, whereas 99mTc-ethyl cysteinate dimer (ECD) reflects not only perfusion but also the metabolic status of brain tissue. We compared 99mTc-ECD single-photon emission CT (SPECT) with 99mTc-HMPAO SPECT early after recanalization by local intraarterial thrombolysis (LIT) in patients with acute embolic middle cerebral artery occlusion. We also assessed the predictive value of 99mTc-HMPAO and 99mTc-ECD SPECT for the development of ischemic brain damage. METHODS: 99mTc-HMPAO and consecutive 99mTc-ECD SPECT studies were performed in 15 patients within 3 hours of LIT. The two SPECT studies were obtained independently using a subtraction technique. SPECT evaluation was performed using semiquantitative region-of-interest analysis. Noninfarction, infarction, and hemorrhage were identified by follow-up CT or MR imaging. RESULTS: Forty-five lesions were identified (21 noninfarctions, 19 infarctions, and five hemorrhages). Regardless of 99mTc-HMPAO SPECT findings, lesions showing isoactivity (count rate densities of 0.9 to 1.1 as compared with the contralateral side) on 99mTc-ECD SPECT were salvaged. Lesions with hypoactivity (values < 0.9) on 99mTc-ECD SPECT developed irreversible brain damage. Hemorrhage appeared in lesions with both hyperactivity (values > 1.1) on 99mTc-HMPAO SPECT and hypoactivity on 99mTc-ECD SPECT. CONCLUSION: The brain distribution of 99mTc-ECD in a reperfused area identified by 99mTc-HMPAO SPECT early after recanalization of acute ischemic stroke is dependent on cerebral tissue viability. By combining 99mTc-ECD and 99mTc-HMPAO SPECT, performed within the first few hours of LIT, it is possible to identify patients at risk for hemorrhagic transformation reliably.

Aged↗
PubMed2001

Dynamic and static 99mTc-ECD SPECT imaging of subacute cerebral infarction: comparison with 133Xe SPECT.

UNLABELLED: 99mTc-ethylcysteinate dimer (99mTc-ECD) SPECT imaging reportedly fails to show reflow hyperemia in patients with subacute stroke. This study attempts to determine the clinical usefulness of dynamic 99mTc-ECD SPECT in evaluating regional blood flow in subacute cerebral infarction and the kinetic behavior of 99mTc-ECD in infarct areas. METHODS: 133Xe and consecutive dynamic and static 99mTc-ECD SPECT studies were performed on 24 patients with cortical infarction in the middle cerebral artery territory 13-15 d after the onset of a stroke. Image contrast between infarct and contralateral control areas on 99mTc-ECD tomograms (ECD uptake ratio) was compared with that on cerebral blood flow (CBF) images obtained using 133Xe inhalation (CBF ratio). RESULTS: In all cases, ECD uptake ratios from static images were lower than CBF ratios. This tendency was obvious when CBF in the infarct area increased above the normal control value, and no significant correlation was found between ECD uptake ratios from static images and CBF ratios. Only in the infarct areas with CBF below the normal control value, however, was a significant correlation between the two maintained (r = 0.795; P = 0.0011). A very strong correlation was found between CBF ratios and ECD uptake ratios on both the first dynamic scan (36 s after injection) (r = 0.991; P < 0.0001) and the second dynamic scan (72 s after injection) (r = 0.945; P < 0.0001). The correlation coefficient decreased in a time-dependent manner, with no significant correlation observed after the fourth dynamic scan (144 s after injection). On the other hand, significant correlations were observed on all dynamic scans only in the infarct areas with CBF below the control value. CONCLUSION: Super-early images of dynamic 99mTc-ECD SPECT provide a close imaging contrast with CBF and reveal reflow hyperemia in areas with irreversible changes produced by subacute stroke, which static 99mTc-ECD SPECT images fail to show. Decreased retention of the tracer in the infarct areas with hyperperfusion causes an underestimation of CBF on static 99mTc-ECD SPECT images. Given these results, we believe that dynamic 99mTc-ECD SPECT is an effective clinical tool to evaluate regional blood flow in subacute cerebral infarction.

Adult↗
PubMed2001

[Distal anterior inferior cerebellar artery aneurysms: report of three cases and literature review].

Aneurysm at the distal portion of the anterior inferior cerebellar artery (AICA) is uncommon and only 55 cases have been documented in the literature. Here we report an additional three cases with review of the literature. All three patients presented with subarachnoid hemorrhage. The ruptured aneurysms were located at the meatal loop of the AICA in all three patients and one patient had another unruptured aneurysm at the lateral branch distal to the meatal loop. Two patients underwent surgical trapping of the aneurysms, and the other patient was treated with endovascular coiling because of poor clinical condition. Increase of hearing disturbance was found in two patients who underwent surgery or endovascular coiling, respectively. Clinical features and treatment of these rare lesions are discussed with reference to the 7th and 8th nerve impairments as preoperative symptoms and postoperative complications.

Adult↗
PubMed2000

Diffusion-weighted MRI and selection of patients for fibrinolytic therapy of acute cerebral ischaemia.

Treatment of patients with acute cerebral ischaemic events remains controversial. We investigated the reversibility of high signal intensity on diffusion-weighted (DW) MRI after acute local intra-arterial fibrinolysis (LIF) and the feasibility of DW MRI for selecting patients for acute LIF. Nine patients with acute middle cerebral artery embolic occlusion underwent single-photon emission computed tomography (SPECT) and DW MRI followed by acute LIF using tissue plasminogen activator. Recanalisation was observed in all patients, and eight improved clinically. The area of high signal intensity on pretreatment DW MRI was smaller than the low-uptake area on SPECT in all patients, and went on to infarction, as detected by MRI or CT 3 days after onset in all patients. It appears to correlate, at least clinically, with irreversible brain damage. Therefore, acute LIF should not be performed in patients with areas of high signal intensity in the cortex responsible for the symptoms. SPECT remains important, because areas normal on DW MRI with low uptake on SPECT often contribute to functional prognosis.

Acute Disease↗
PubMed2000

Combined neuroendovascular stenting and coil embolization for cervical carotid artery dissection causing symptomatic mass effect.

BACKGROUND: Carotid artery dissection manifesting with symptomatic mass effect has been treated surgically according to the previous literature. Recently, some cases of carotid artery dissection manifesting with ischemic symptoms were treated successfully with endovascular insertion of coils after stenting. METHODS: A 42-year-old man with spontaneous dissection of the left cervical internal carotid artery (ICA) presented with the major complaint of left neck swelling and pain that was considered to be the mass effect of a pseudoaneurysm caused by dissection of the ICA. Endovascular therapy using a stent and coils was performed. The self-expanding stent was deployed to cover the neck of the pseudoaneurysm. A microcatheter was then guided through the stent mesh into the aneurysm, and coils were placed to pack it. RESULTS: Four months later, angiography revealed complete embolization of the aneurysm with preserved flow in the ICA. The mass effect attributable to the pseudoaneurysm was relieved symptomatically as well as radiologically. CONCLUSION: Cervical artery dissection with symptomatic mass effect++ can be treated successfully by the combination of stent and coils. This may be considered as an alternative to conventional proximal ligation, extracranial-intracranial bypass, or direct surgical repair.

Adult↗
PubMed2000

Endovascular treatment of aneurysms associated with cerebral arteriovenous malformations: experiences after the introduction of Guglielmi detachable coils.

The authors have treated 172 patients with arteriovenous malformation (AVM) since 1993. Among them, 25 patients had aneurysms with a total number of 43. The aneurysms were divided into four groups; proper feeder aneurysm (4), flow-related distal aneurysm (beyond the circle of Willis or M1, 7), flow-related proximal aneurysm (26) and remote aneurysm (6). Guglielmi detachable coil (GDC) embolisation was performed in 12 patients with 15 aneurysms. Gamma knife radiosurgery for AVM was performed in 10 of those 12 patients. Two of the proper feeder aneurysms were embolised with liquid material, together with the corresponding part of the AVM. The other aneurysms were treated surgically (14) or observed (12). There was no bleeding from aneurysms after treatment. In conclusion, GDC embolisation is a useful treatment for aneurysms associated with AVM, especially if the AVM is treated by radiosurgery. Liquid embolisation of a proper feeder aneurysm is one of the treatment options. Ltd.

Adult↗
PubMed2000

[An arterial dissection of the distal anterior inferior cerebellar artery treated by endovascular therapy].

A rare case of a dissection of the distal anterior inferior cerebellar artery (AICA) is presented. A 68-year-old woman with sudden onset of headache was admitted. Computed tomographic (CT) scan demonstrated no subarachnoid hemorrhage. Seven days later, CT scan revealed subarachnoid and intraventricular hemorrhage. Left vertebral angiogram showed an aneurysmal dilatation on the distal AICA with a diagnosis of suspected arterial dissection. At that time, we chose delayed craniotomy to observe the lesion directly. However, rebleeding causing aggravation of the patient's systemic condition delayed radical treatment. 19 days after rebleeding, by a superselective angiogram, endovascular treatment was selected to prevent further bleeding. The lesion was diagnosed as dissection of the AICA. The parent AICA was occluded with a Guglielmi detachable coil and fibered platinum coils. Dissection of the distal portion of the cerebellar artery is rare. Only six cases have been reported in the posterior inferior cerebellar artery (PICA) and two cases in the superior cerebellar artery (SCA). However, to our knowledge, no such case has been reported in the AICA. Ruptured dissection of distal PICA or SCA is reported to require early treatment to prevent further bleeding. Ruptured dissection of the distal AICA also requires early treatment. Two cases of distal dissection of PICA and SCA successfully treated by endovascular treatment are reported. Endovascular treatment has some benefits in that it does not always require general anesthesia and in that it can follow diagnostic angiography. On the other hand, saccular aneurysms of the distal AICA do not always require early treatment, such as removal of hematoma because of low incidence of vasospasm. So, to decide the treatment, precise diagnosis of the dissection is very important.

Aged↗
PubMed2000

[Intraaneurysmal embolization and parent artery trapping to treat a giant partial thrombosed vertebral artery aneurysm after surgical proximal clipping].

We encountered a case with a giant partially-thrombosed vertebral artery aneurysm successfully treated by endovascular trapping following a surgical parent artery clipping two years previously. The patient complained only of headache on her admission. Initial CT showed no subarachnoid hemorrhage, and MRI of the left anterior aspect of the pons showed flow void and hematoma. The angiogram showed fusiform dilatation of the left vertebral artery just proximal to the vertebral union. At first, the patient was treated by surgical proximal clipping of the left vertebral artery, under a diagnosis of arterial dissection. Her symptom improved and the angiogram showed a slight retrograde aneurysmal filling after the operation. Two years later, she complained of dysphasia, right hemiparesis, and hemidysesthesia caused by the compression of the brain stem. On MRI study, a partially-thrombosed giant aneurysm was detected in the left anterior aspect of the brain stem. The retrograde filling did not change remarkably on the angiogram. We performed the GDC embolization of the left distal vertebral artery and non-thrombosed residual neck with an assisting balloon positioned through the right vertebral artery to the basilar artery. After the embolization, the patient's neurological deficits caused by the compression of the brain stem disappeared. MRI study showed the mass volume reducing gradually over a two-years follow-up period. Treatment for a partially-thrombosed giant vertebral artery aneurysm is difficult and controversial. It is necessary to shut off the blood flow into the aneurysm completely, so we consider that endovascular trapping with intraaneurysmal embolization is the most effective procedure.

Embolization, Therapeutic↗
PubMed1999

Antegrade recanalization of completely embolized internal carotid artery after treatment of a giant intracavernous aneurysm: a case report.

BACKGROUND: Parent artery occlusion is one of the traditional methods of treatment for unclippable aneurysms. However, parent artery occlusion may not result in permanent exclusion of the aneurysm from the systemic circulation. We present a case of cerebral aneurysm treated by proximal embolization of the parent artery, which recanalized during the follow-up period. CASE DESCRIPTION: A 69-year-old woman presented with a right blepharoptosis and diplopia. A large aneurysm arising from the cavernous portion of the right internal carotid artery was found and endovascularly excluded from the cerebral circulation by proximal internal carotid artery occlusion with balloons. Eleven days after treatment, occlusion of the parent artery and obliteration of the aneurysm were angiographically confirmed. However, the parent artery was found to be recanalized with nearly total obliteration of the aneurysm at the follow-up 6 months after treatment. CONCLUSION: Angiography suggested that recanalization took place through the vaso vasorum. We believe that recanalization was induced by marginal cerebral blood flow in the ipsilateral hemisphere.

Aged↗
PubMed1999

The relationship between cerebral infarction and angiographic characteristics in childhood moyamoya disease.

BACKGROUND AND PURPOSE: In childhood-onset moyamoya disease, the angiographic disease process of stenoocclusive lesions is progressive, and cerebral infarctions often develop as a result of ischemia. Our purpose was to determine how the severity of stenoocclusive lesions in the anterior and posterior circulations affects the distribution of cerebral infarction in patients with childhood-onset moyamoya disease. METHODS: In 69 patients with childhood-onset moyamoya disease, angiograms were reviewed for stenoocclusive lesions, and CT scans, MR images, or both were reviewed for the sites and extent of cerebral infarction. The relationship between the angiographic and CT/MR findings was examined. RESULTS: The prevalence and degree of stenoocclusive lesions of the posterior cerebral artery (PCA) significantly correlated with the extent of lesions around the terminal portion of the internal carotid artery (ICA). The prevalence of infarction significantly correlated with the degree of stenoocclusive changes of both the ICA and PCA. Infarctions tended to be distributed in the anterior borderzone in less-advanced cases, while in more advanced cases lesions were additionally found posteriorly in the territory of the middle cerebral artery, the posterior borderzone, and the PCA territory. CONCLUSION: Our results indicate that progressive changes of the anterior and posterior circulations are associated with the distribution of cerebral infarction, culminating in a patchily disseminated or honeycomb pattern of infarction on CT and MR studies in late stages of the disease.

Adolescent↗
PubMed1999

[A case of unruptured cerebral aneurysm treated by intra-aneurysmal embolization during outpatient hemodialysis for chronic renal failure].

A 70-year-old woman, who had been receiving hemodialysis in a local hospital every other day for 2 years, complained of occasional headaches. Magnetic resonance imaging showed a large middle cerebral artery (MCA) aneurysm. Angiography in the midterm day of hemodialysis demonstrated a large aneurysm on the right MCA bifurcation. Her chronic renal failure made us hesitate to perform craniotomy. Intra-aneurysmal Guglielmi detachable coil (GDC) embolization was performed also in the midterm day of hemodialysis. She was admitted to our hospital after hemodialysis on the day before the embolization. The embolization was carried out under local anesthesia and systemic heparinization. The aneurysm was almost completely embolized with five GDCs. She was transferred to the local hospital to receive the next hemodialysis on the day after the embolization. Patients with chronic renal failure are not suitable for neurosurgical therapy because mortality of patients undergoing dialysis is 45-80%, which is mainly due to disequilibrium syndrome and a hemorrhagic tendency. We propose that some cases like this case should be treated with an intra-vascular neurosurgical technique. In conclusion, this report demonstrates that intra-aneurysmal embolization is less invasive and is a more suitable treatment for patients who are considered to be at high risk for surgery and general anesthesia.

Aged↗