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.

A Newly Developed 3 cm Marker Balloon Microcatheter.

SUMMARY: No balloon microcatheter with a 3 cm marker has been developed to date.We developed a new balloon microcatheter with a double marker. This balloon microcatheter, with an outer diameter of 2.8 F, has a balloon on the most distal portion with a maximum inflation diameter of 4 mm and two markers, one is on the tip and the other is 3 cm proximal to the tip. This balloon microcatheter would make interventional procedures, especially for parent artery occlusion, simple to perform and safer.

Periprocedural monitoring with regional cerebral oxygen saturation in carotid artery stenting.

SUMMARY: Hemodynamic instability during and after carotid artery stenting (CAS) may reduce cerebral blood flow (CBF), leading to cerebral ischemia. To investigate changes in CBF in the periprocedural period, we continuously recorded the regional cerebral oxygen saturation (rSO2) using near-infrared spectroscopy. In 46 consecutive patients with carotid artery stenosis, rSO2 was continuously recorded during and after CAS. In addition, the patients underwent SPECT to evaluate a change in CBF on the next day after CAS. Introprocedural bradycardia (heart rate < 50 bpm) occurred in 21 patients (46%) including one transient cardiac arrest. Intraprocedural hypotension (systolic blood pressure < 80 mmHg) occurred in 18 patients (39%), and 16 of them showed prolonged hypotension. The rSO2 in patients with bradycardia/hypotension during CAS was significantly less than that in patients without them (p < 0.01). Moreover, the SPECT on the next day after CAS demonstrated that the ipsilateral CBF in patients with bradycardia/hypotension during CAS significantly more than that in patients without them (p < 0.05). Intraprocedural hemodynamic instability resulted in a significant decrease in rSO2, leading to a possible severe cerebral ischemia. In addition, intraprocedural bradycardia/hypotension might be related with postprodedural hyperperfusion, causing the morbidity and mortality after CAS.

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.

Endovascular GDC Treatment of an Idiopathic Carotid-Cavernous Fistula Caused by Aneurysmal Rupture of the Intra-Cavernous Carotid Artery. Case Report.

SUMMARY: Aneurysmal rupture of the intra-cavernous carotid artery may cause idiopathic carotid-cavernous fistula (CCF), and the treatment choice for occluding shunting fistula in this type of CCF is an endovascular approach using detachable balloons. However, little has been reported on treating such lesions with the intra-aneurysmal embolization using Guglielmi detachable coils (GDCs).To our knowledge, ours is the first reported case of successful treatment by selective intra-fistula and intra-aneurysmal embolization with GDCs. A 74-year-old woman exhibited proptosis and chemosis of her left eye over a period of one month. Symptoms of double vision in conversion and pulsatile murmur in her left eye were also noted. Angiography revealed an intra-cavernous aneurysm of the left internal carotid artery (ICA) with a shunting fistula, which drained into the dilated cavernous sinus, superior orbital vein (SOV), superior petrosal sinus, inferior petrosal sinus, and pterygoid plexus.We thought the fistula would occlude by intra-aneurysmal embolization, but we had no confidence of tight packing of the aneurysm since the aneurismal neck was relatively wide. So, we embolized the venous side of the shunting fistula and then the dome of the aneurysm with GDCs. Immediately after the operation, her symptoms and signs were ameliorated, and complete occlusion of the CCF was observed on long-term follow-up. We suggest selective intrafistula and intra-aneurysmal embolization with GDCs as an alternative method of treatment of idiopathic CCF originating from aneurysmal rupture of the intra-cavernous carotid artery.

Retinal embolization and cerebellar asymptomatic embolization after carotid stenting using distal balloon protection. A case report.

SUMMARY: We describe a rare case of having both symptomatic ipsilateral retinal embolization and asymptomatic cerebellar embolization occurring after carotid stenting with use of distal protect device. In this case, external carotid angiograms revealed accessory meningeal arteryophthalmic artery and occipital artery-vertebral artery anastomoses. This case suggested that the protection for external carotid artery should be considered during carotid stenting to avoid retinal embolization and cerebellar or cerebral embolization in cases showing angiographical anastomoses between external carotid artery and ophthalmic artery or intracranial arteries.

[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.

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.

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.

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.

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.

Guidewire-induced carotid cavernous fistula.

SUMMARY: A rare case of carotid cavernous fistula occurring during endovascular embolization of the left carotid cave aneurysm in a 48-year-old female is reported. It was thought to be caused by the tear of a small branch derived from the intracavernous internal carotid artery while the guidewire was passing the sharp posterior bend of the intracavernous internal carotid artery. The left carotid cave aneurysm was completely occluded with five Guglielmi detachable coils assisted by neck plasty technique. It was decided to follow-up the carotid cavernous fistula since it was asymptomatic. Follow-up angiogram performed two weeks later revealed spontaneous obliteration of the carotid cavernous fistula.

Formation of a Liquid Jet by Interaction between a Laser-induced Bubble and a Shock Wave.

SUMMARY: There are some problems such as a narrow therapeutic time window and severe side effects of fibrinolytics in the therapy of cerebral embolisms. Therefore, it is necessary to develop a new method to remove a cerebral thrombus more rapidly with fewer fibrinolytics. A Q-switch pulsed holmium (Ho): YAG laser with 86 mJ/pulse, pulse duration of 200ns and wavelength of 2.1 mm was used. The laser beam was transmitted through a 0.6 mm diameter quartz optical fiber. Experiments were conducted in a stainless steel container equipped with observation windows . The test chamber was filled with distilled water at 283K. At first, the formation of laser-induced bubbles in a 4 mm diameter glass tube was observed. The bubble gradually expanded and reached a maximum size at about 1 ms after irradiation. A shock wave induced by ignition of silver azide pellet was interacted with it at 500mus before Ho:YAG laser irradiation, which resulted in forming a liquid jet. This liquid jet penetrated into an artificial thrombus made of gelatin, and its maximum penetration depth was 4.2 mm, which was nearly twice deeper than the laser irradiation only (2.2 mm). Combination of this liquid jet and fibrinolytics will realize more rapid recanalization with fewer drugs.

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 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.