Cerebral hemodynamic disturbance in dural arteriovenous fistula with retrograde leptomeningeal venous drainage: a prospective study using (123)I-iodoamphetamine single photon emission computed tomography.

OBJECT: The severity of cerebral hemodynamic disturbance caused by retrograde leptomeningeal venous drainage (RLVD) of a dural arteriovenous fistula (dAVF) is related to neurological morbidity and unfavorable outcome. However, the cerebral hemodynamics of this disorder have not been elucidated well. The aim of this study was to assess the relationship between the cerebral venous congestive encephalopathy represented as a high-intensity area (HIA) on T2-weighted MR images and the cerebral hemodynamics examined by (123)I-iodoamphetamine (IMP) single photon emission computed tomography (SPECT), as well as the predictive value of (123)I-IMP SPECT for the development and reversibility of venous congestion encephalopathy. METHODS: Based on the pre- and posttreatment T2 HIAs associated with venous congestion encephalopathy, patients were divided into 3 groups: a normal group, an edema group, and an infarction group. The regional cerebral blood flow (rCBF) at the region with RLVD was analyzed by (123)I-IMP SPECT, and the results were compared among the groups. RESULTS: There were 11, 6, and 3 patients in the normal, edema, and infarction groups, respectively. No patients in the normal group showed any symptoms related to venous congestion. In contrast, all patients in the edema and infarction groups developed neurological symptoms. The rCBF in the edema group was significantly lower than that in the normal group, and significantly higher than that in the infarction group. The cerebral vascular reactivity (CVR) of the infarction group was significantly lower than that of the normal and edema groups. After treatment, the neurological signs disappeared in the edema group, but only partial improvement was seen in the infarction group. The rCBF also significantly increased in the normal and edema groups, but not in the infarction group. CONCLUSIONS: Quantitative rCBF measurement is useful for evaluating hemodynamic disturbance in dAVF with RLVD. The reduction of rCBF was strongly correlated with the severity of venous congestive encephalopathy, and loss of CVR is a reliable indicator of irreversible venous infarction caused by RLVD.

Anchor coil technique for arteriovenous fistula embolization. A technical note.

We describe a case of arteriovenous fistula (AVF) successfully treated by coil embolization with an anchor coil inserted in the varix to facilitate dense packing at the shunting site. AVF of the left anterior choroidal artery (AChoA) draining into the ipsilateral basal vein of Rosenthal was incidentally found in a newborn female. A single detachable coil was inserted as an anchor into the varix adjacent to the shunt, and the microcatheter was pulled back to the shunting point. Three more detachable coils were delivered at the shunting point without migration under the support of the anchor coil, and the AVF was successfully obliterated with preservation of AChoA blood flow. The anchor coil technique can reduce the risk of coil migration and the number of coils required.

A rare case of focal multiple medullary venous malformations with ipsilateral cerebral surface varix.

We report here a rare case of focal multiple venous malformations (VMs) in the white matter, via a draining vein arising from each VM, connecting with an ipsilateral cerebral surface venous varix. The male teen was asymptomatic neurologically. A diagnostic process using of MRI/MRDSA in this extremely rare entity is important as the more incidental discovery is expected with increasing opportunities of performing brain CT/MRI for various indications.

Intracranial pial arteriovenous fistula caused by dural tenting: case report.

We describe a rare case where a patient developed intracranial pial arteriovenous (AV) fistula due to dural tenting. The patient was a 63-year-old woman who had undergone neck clipping for an unruptured middle cerebral artery (MCA) aneurysm. The surgery was performed without any problems and her postoperative course was uneventful. Two weeks after cerebral angiography operation revealed a pial AV fistula fed by the right MCA and drained into the vein of Trolard through the Sylvian vein which had not existed before surgery. Being diagnosed as de novo pial AV fistula, surgical repair was performed. The AV fistula was located just beneath the dural tenting. The fistulous point was confirmed with fluorescein video angiography and obliterated using a clip. Although rare, we should pay attention to the AV fistula due to dural tenting as the complications of cranial surgery.

Advantage of microscope integrated for both indocyanine green and fluorescein videoangiography on aneurysmal surgery: case report.

Neck clipping of a large middle cerebral artery aneurysm was performed using a newly developed surgical microscope integrated with modules for both indocyanine green (ICG) and fluorescein videoangiography. During surgery, ICG and fluorescein videoangiography by intra-arterial or intravenous injection were safely carried out without interrupting the surgical procedure. Based on the findings obtained from the case, we evaluated the differences between the dyes and the injection routes. With intra-arterial injection, fluorescein offered sharper contrast images and was better at depicting fine arteries than ICG. Patchy staining of vessel walls was observed in intravenous fluorescein videoangiography, while it was not evident in ICG. Intra-arterial injection method had a great advantage in the rapid clearance of the dyes, which allowed us to perform repeated videoangiography within a short period, and was useful in detecting incomplete clipping in this case; however, catheter insertion requires additional work and carries a potential risk. Use of a microscope integrated for both ICG and fluorescein videoangiography would be another method for repeated evaluation. Namely, alternate use of the dyes enables us to perform videoangiography in a short time even via intravenous injection.

In-stent thrombosis after carotid artery stenting despite sufficient antiplatelet therapy in a bladder cancer patient.

In-stent thrombosis (IST) after carotid artery stenting (CAS) is a rare but potentially devastating complication. We present a case of early IST after CAS despite sufficient antiplatelet therapy in a patient with bladder cancer. A 77-year-old man under preventive triple antiplatelet therapy underwent CAS without any intra- or periprocedural complications. However, the patient developed a large asymptomatic IST 6 days after CAS. Anticoagulant therapy with argatroban was reintroduced to treat IST concomitant with antiplatelet agents. Subsequently, the IST shrank and disappeared without any thrombotic symptoms. Malignancy is regarded as an acquired thrombophilic condition associated with a significant risk of thrombosis. In the field of coronary stents, cancer is associated with a significant increasing risk of IST. The cause of IST in our case was possibly related in hypercoagulable state because of the patient's cancer. Attention for IST should be paid in CAS cases with these risk factors, and repeated examination is recommended.

Effects of cilostazol on cerebral vasospasm after aneurysmal subarachnoid hemorrhage: a multicenter prospective, randomized, open-label blinded end point trial.

OBJECT: Cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH) is a major cause of subsequent morbidity and mortality. Cilostazol, a selective inhibitor of phosphodiesterase 3, may attenuate cerebral vasospasm because of its antiplatelet and vasodilatory effects. A multicenter prospective randomized trial was conducted to investigate the effect of cilostazol on cerebral vasospasm. METHODS: Patients admitted with SAH caused by a ruptured anterior circulation aneurysm who were in Hunt and Kosnik Grades I to IV and were treated by clipping within 72 hours of SAH onset were enrolled at 7 neurosurgical sites in Japan. These patients were assigned to one of 2 groups: the usual therapy group (control group) or the add-on 100 mg cilostazol twice daily group (cilostazol group). The group assignments were done by a computer-generated randomization sequence. The primary study end point was the onset of symptomatic vasospasm. Secondary end points were the onset of angiographic vasospasm and new cerebral infarctions related to cerebral vasospasm, clinical outcome as assessed by the modified Rankin scale, and length of hospitalization. All end points were assessed for the intention-to-treat population. RESULTS: Between November 2009 and December 2010, 114 patients with SAH were treated by clipping within 72 hours from the onset of SAH and were screened. Five patients were excluded because no consent was given. Thus, 109 patients were randomly assigned to the cilostazol group (n = 54) or the control group (n = 55). Symptomatic vasospasm occurred in 13% (n = 7) of the cilostazol group and in 40% (n = 22) of the control group (p = 0.0021, Fisher exact test). The incidence of angiographic vasospasm was significantly lower in the cilostazol group than in the control group (50% vs 77%; p = 0.0055, Fisher exact test). Multiple logistic analyses demonstrated that nonuse of cilostazol is an independent factor for symptomatic and angiographic vasospasm. The incidence of new cerebral infarctions was also significantly lower in the cilostazol group than in the control group (11% vs 29%; p = 0.0304, Fisher exact test). Clinical outcomes at 1, 3, and 6 months after SAH in the cilostazol group were better than those in the control group, although a significant difference was not shown. There was also no significant difference in the length of hospitalization between the groups. No severe adverse event occurred during the study period. CONCLUSIONS: Oral administration of cilostazol is effective in preventing cerebral vasospasm with a low risk of severe adverse events. Clinical trial registration no. UMIN000004347, University Hospital Medical Information Network Clinical Trials Registry.

Intra-arterial injection fluorescein videoangiography in aneurysm surgery.

BACKGROUND: To visualize blood flow in the arteries and aneurysm during surgery, intravenous fluorescence videoangiography has been used. However, the image contrast with this procedure is diminished by repeated study because the dye remains for about 10 minutes after injection. OBJECTIVE: To determine the optimal dye concentration and to clarify the usefulness of fluorescein videoangiography by intra-arterial dye injection. METHODS: In the pilot study, fluorescein sodium dissolved at various concentrations was illuminated with excitation light, and fluorescence was detected by cameras. The fluorescence of 0.001% fluorescein sodium solution mixed with plasma at various concentrations was then examined. In 13 aneurysm patients, dye solution was administered through the catheter for intraoperative digital subtraction angiography. The intravenous injection method was also performed, and the findings were compared. RESULTS: Dye was clinically used at a concentration of 0.005% to 0.1% on the basis of the results of the pilot study. Fluorescence emission from the vessels and aneurysms was clearly observed by both methods; however, arterial injection provided brighter emission, resulting in clearer demonstration of the bloodstream than venous injection. Dye clearance was also quicker, which allowed repeat injections without delay. Dye filling in the aneurysm indicating incomplete occlusion was detected in 2 cases, and occlusion of the perforating artery was observed in 2 cases. CONCLUSION: Intra-arterial fluorescein videoangiography provides brighter and clearer imaging of blood flow with a smaller dose of dye than intravenous videoangiography. It can be repeated within a short time and is useful for detecting incomplete clipping or unexpected obstruction of arteries.

Endoscopic indocyanine green video angiography in aneurysm surgery: an innovative method for intraoperative assessment of blood flow in vasculature hidden from microscopic view.

Recently, intraoperative fluorescence video angiography using indocyanine green (ICG) has been widely used in aneurysm surgery. This is a simple and useful method to confirm complete occlusion of the aneurysm lumen and preservation of blood flow in the arteries around the aneurysm. However, the observation field of ICG video angiography is limited under a microscope, making it difficult to confirm the flow in the arteries behind the parent arteries or aneurysm. The authors developed a new technique of intraoperative endoscopic ICG video angiography to assess the blood flow in perforating arteries hidden by the parent arteries or aneurysm. The endoscope emits excitation light with a wavelength of approximately 800 nm, and video images were obtained through a cut filter. The authors used this ICG fluorescence endoscope in treating 3 patients with unruptured cerebral aneurysms. During clip placement, the endoscope was inserted to confirm aneurysm occlusion. Then, ICG was intravenously administered, and the fluorescence in the vessels was observed via the endoscope as well as under the microscope. The blood flow in the perforating arteries was clearly identified, and no procedural complication occurred. The authors conclude that the technique is very useful and facilitates intraoperative real-time assessment of the patency of perforating arteries behind parent arteries or aneurysms.

Direct clipping of a thrombosed giant cerebral aneurysm after thrombectomy without bleeding to minimize the temporary occlusion time-technical case report-.

A 75-year-old man was referred to our hospital with a thrombosed giant middle cerebral artery aneurysm manifesting as progressive memory disturbance and disorientation. Magnetic resonance imaging and conventional angiography revealed a partially thrombosed giant aneurysm of the left middle cerebral artery bifurcation and edema of the adjacent brain which had enlarged compared to 3 months before. Surgery was performed through a left frontotemporal craniotomy. After exposure of the aneurysm neck, we tried to apply a clip, which slipped due to the intraaneurysmal thrombus. Intraoperative motor evoked potential monitoring showed decreased amplitude. Therefore, the aneurysm dome was incised and the intraaneurysmal thrombus near the neck was shaved with the ultrasonic aspirator, followed by neck clipping of the aneurysm. The residual thrombus was safely removed. Transient right hemiparesis was observed after surgery, but his memory disturbance gradually improved. Giant thrombosed aneurysm can be treated by reduction of the thrombus from the far side to the lumen to reduce the duration of parent artery occlusion required for clipping.