Longitudinal changes in 18 F-THK5351 positron emission tomography in corticobasal syndrome.

BACKGROUND AND PURPOSE: Corticobasal syndrome (CBS) is pathologically characterized by tau deposits in neuronal and glial cells and by reactive astrogliosis. In several neurodegenerative disorders, 18 F-THK5351 has been observed to bind to reactive astrocytes expressing monoamine oxidase B. In this study, the aim was to investigate the progression of disease-related pathology in the brains of patients with CBS using positron emission tomography with 18 F-THK5351. METHODS: Baseline and 1-year follow-up imaging were acquired using magnetic resonance imaging and positron emission tomography with 18 F-THK5351 in 10 subjects: five patients with CBS and five age-matched normal controls (NCs). RESULTS: The 1-year follow-up scan images revealed that 18 F-THK5351 retention had significantly increased in the superior parietal gyrus of the patients with CBS compared with the NCs. The median increases in 18 F-THK5351 accumulation in the patients with CBS were 6.53% in the superior parietal gyrus, 4.34% in the precentral gyrus and 4.33% in the postcentral gyrus. In contrast, there was no significant increase in the regional 18 F-THK5351 retention in the NCs. CONCLUSIONS: Longitudinal increases in 18 F-THK5351 binding can be detected over a short interval in the cortical sites of patients with CBS. A monoamine oxidase B binding radiotracer could be useful in monitoring the progression of astrogliosis in CBS.

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.

Dissociation of letter and picture naming resulting from callosal disconnection.

BACKGROUND: Detailed mapping of the corpus callosum for functional fractionation in humans remains incomplete. OBJECTIVE: To examine separable interhemispheric transfer of visual information by callosal fibers, especially in the splenium. METHODS: We examined callosal disconnection signs in a 14-year-old boy with a lesion confined to the posterior part of the splenium and reviewed reported cases with callosal lesions. RESULTS AND CONCLUSION: The patient presented with left hemialexia as the only manifestation of callosal disconnection syndrome. The only difficulty demonstrated was in reading aloud or copying letters, which were presented tachistoscopically to the left visual field, with his right hand. He could copy letters presented to his left visual field with his left hand, however. Therefore, left hemialexia was not due to hemiamblyopia or hemineglect. There was no anomia for pictures and colors in the left visual field. MRI revealed that the lesion was limited to the ventroposterior end of the splenium. Review of 40 reported patients with callosal lesions suggests that the anterior to middle part of the splenium is involved in transferring picture information from the language-nondominant hemisphere to the language-dominant hemisphere and that the ventroposterior part is involved in transferring letter information.

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.

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.

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.

Spontaneous disappearance of a huge cerebral arteriovenous malformation: case report.

A case of spontaneous disappearance of a cerebral arteriovenous malformation (AVM) is reported. A 59-year-old woman, who had been diagnosed as having a huge AVM in the left occipital lobe 6 years before and who was monitored without treatment, complained of a sudden headache and vomiting. Computed tomography revealed an acute subdural hematoma, intracerebral hematoma, and subarachnoid hemorrhage, for which a craniotomy was performed. Cerebral angiograms performed 9 days after the operation demonstrated a decrease in the size of the AVM. Repeated cerebral angiograms performed a month later demonstrated complete disappearance of the AVM. Follow-up angiograms performed 19 months after hemorrhage confirmed complete disappearance of the AVM. Spontaneous disappearance is known to occur occasionally in small AVMs but rarely in huge ones such as the one presented here. Several possible mechanisms for spontaneous disappearance of AVMs are discussed.

Successful treatment of an arteriovenous malformation by chemical embolization with estrogen followed by conventional radiotherapy.

A case of the successful treatment of a thalamic arteriovenous malformation (AVM) by chemical embolization with conjugated estrogen followed by conventional radiotherapy is described. A 22-year-old woman suddenly developed headache, nausea, and consciousness disturbance. Computed tomographic scans revealed left thalamic and ventricular bleeding. Angiograms disclosed a left thalamic AVM with a maximum diameter of 2 cm. The AVM was fed mainly by the left medial posterior choroidal artery and drained into the basal vein. Chemical embolization with 300 mg of conjugated estrogen via a leak balloon catheter was carried out. Although the size of the nidus of the AVM was unchanged immediately after embolization, it became smaller 9 days later. In spite of the further reduction in size, the AVM still existed 2 years later. Conventional radiotherapy with a total dose of 30 Gy was performed. Follow-up angiograms 40 months after radiotherapy demonstrated disappearance of the AVM. This case report suggests progressive and stable embolizing capabilities of chemical embolization with conjugated estrogen and its suitableness for following radiotherapy, including stereotactic radiosurgery.

Intracerebral schwannoma: case report.

A case of intraparenchymal schwannoma is presented. The neuroradiological findings of reported intraparenchymal schwannomas, including the case reported here, are discussed. The specific tumor characteristics are emphasized. This report appears to be the only documentation as a result of magnetic resonance imaging of this specific tumor.

Selective and superselective infusion of urokinase for embolic stroke.

Intraarterial administration of urokinase using Tracker microcatheter was performed in 11 patients with acute cerebral infarction caused by embolic occlusion of the internal carotid or the middle cerebral artery. Recanalization was observed in seven cases (64%) following the fibrinolytic therapy, and the time until recanalization from the start of the treatment was on the average 2.8 hours. Recanalization was seen in five out of six cases that received superselective infusion of urokinase, while it was seen in two out of five cases that received selective infusion. This study suggests that superselective infusion of urokinase is an excellent therapeutic method for embolic occlusion of the cerebral artery.

Combined intravascular parent artery and ophthalmic artery occlusion for giant aneurysms of the supraclinoid internal carotid artery.

BACKGROUND: Parent artery occlusion is an effective method to treat internal carotid giant aneurysms. However, incomplete parent artery occlusion may cause revascularization. Here, a modification of the parent artery occlusion procedure for giant aneurysms of the internal carotid artery is described. METHODS: Three patients with giant aneurysms of the internal carotid artery at the supraclinoid portion between the origin of the ophthalmic artery and the posterior communicating artery were treated by a combination of parent artery occlusion and occlusion of the origin of the ophthalmic artery. All patients had a giant aneurysm that manifested as cranial nerve palsy due to mass effect. RESULTS: A balloon occlusion test of the ipsilateral internal carotid artery together with the ophthalmic artery showed that permanent occlusion was tolerable. It was confirmed that the ipsilateral eye was supplied by maxilloophthalmic anastomosis instead of the ophthalmic artery. Cranial nerve palsy and visual acuity were markedly improved in two cases after the therapy. Follow-up selective internal and external carotid angiography did not demonstrate the aneurysm. CONCLUSIONS: Combined parent artery and ophthalmic artery occlusion is an effective treatment for a giant aneurysm located between the ophthalmic artery and the posterior communicating artery.

Intra-aneurysmal GDC embolization followed by intrathecal tPA administration for poor-grade basilar tip aneurysm.

BACKGROUND: This 42-year-old male presented with subarachnoid hemorrhage of Hunt and Kosnik Grade IV, complicated by neurogenic pulmonary edema, prolongation of the electrocardiographic Q-Q interval, and acute renal failure. METHODS: Surgical clipping was not indicated, so intra-aneurysmal embolization using Guglielmi detachable coils (GDCs) was performed followed by intrathecal infusion of tissue-type plasminogen activator (tPA) via spinal drainage. RESULTS: The patient made a complete recovery 2 1/2 months later except for partial third cranial nerve palsy. CONCLUSIONS: Intra-aneurysmal GDC embolization followed by intrathecal tPA via spinal drainage is an excellent method for treating aneurysms that are difficult to treat surgically.

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.

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.

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.

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.

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.

Surgical removal of giant basal ganglia arteriovenous malformations through the extended transsylvian approach following preoperative embolization--two case reports.

A 12-year-old boy and a 22-year-old male presented with sudden onset of consciousness disturbance with right-sided hemiparesis and aphasia due to massive intracerebral hemorrhage from giant striocapsular arteriovenous malformations (AVMs). Angiography revealed giant AVMs located at the left basal ganglia in both patients. Large frontotemporal craniotomies were performed following staged embolization of the feeding arteries. Through an extended transsylvian approach, the lesions were totally excised with confirmation using intraoperative digital subtraction angiography. The patients showed a transient postoperative worsening of symptoms, but recovered to their preoperative status at discharge. Motor functions of the right upper and lower extremities were graded 4/5 in both patients. These cases demonstrate that combined use of preoperative embolization and intraoperative angiography allows some giant deep AVMs to be resected with encouraging results.