Objective: To assess the efficacy and safety of intravenous recombinant tissue plasminogen activator (IV-tPA) therapy and combining IV-tPA with neuroendovascular therapy (combined therapy [ComT]) in acute ischemic stroke.
Methods: Among 481 consecutive patients with acute ischemic stroke, we investigated the recanalization rate, clinical outcomes three months after stroke onset, and the incidence of symptomatic intracranial hemorrhage (sICH) in 33 patients who received IV-tPA therapy (0.6 mg/kg for 60 minutes). We performed ComT in 9 of these 33 patients who satisfied the treatment indications.
Results: The recanalization rate immediately after IV-tPA therapy was 39.3% in 28 of the 33 patients, i.e., excluding the five with small-artery occlusions. In the ComT group, the rate of recanalization was 44.4% (4 of the 9 patients). Good and intermediate clinical outcomes (0-3 points on the modified Rankin Scale at three months) were seen in 17 patients (51.5%), and sICH occurred in only one (3.0%). Rates of recanalization (immediately after IV-tPA therapy/ComT) in the internal carotid artery (ICA), the proximal middle cerebral artery (MCA), the distal MCA, and the basilar artery were 0%/ 50%, 42.9%/ 50%, 77.8%/ - and 50%/ 0%, respectively. Among those with ICA and proximal MCA occlusions, a large number of patients had poor outcomes. In fact, the only patients with good outcomes were in the recanalized group.
Conclusion: IV-tPA therapy was not particularly useful in patients with ICA occlusion. However, if used according to strict indications, ComT can be performed safely and might improve the recanalization rate and clinical outcomes of patients with ICA occlusion.

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Objective: The purpose of this study was to clarify efficacy and safety of a combined therapy of intravenous administration of recombinant tissue plasminogen activator (IV rt-PA) followed by an intra-arterial thrombolysis for acute embolic occlusion of cerebral major arteries.
Methods: From January 2008 to March 2010, 27 patients with acute major artery embolic occlusion underwent IV rt-PA, and nine patients, in whom recanalization of the affected arteries was not achieved using IV rt-PA, underwent the combined therapy of IV rt-PA and intra-arterial thrombolysis.
Results: Of the 27 patients treated with IV rt-PA, four patients (15%) showed favorable clinical outcomes 3 months after the treatment. On the other hand, in five of the nine patients treated with the combined therapy (55%), both successful recanalization immediately after the treatment and favorable outcomes at 3 months were obtained. No permanent deficits caused by the combined therapy were observed in the present series.
Conclusion: The combined therapy of IV rt-PA followed by intra-arterial thrombolysis is effective and safe for patients in whom recanalization of the occluded arteries is not achieved immediately after IV rt-PA therapy.

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Object: In endovascular coil embolization for a cerebral aneurysm, coil insertion is usually performed simply by advancing the coil-delivery wire steadily, without any torque handling. However, the relation between coil insertion force and coil/microcatheter behavior is complex and has not been sufficiently investigated. In this experiment, the authors measured the coil insertion force and observed the coil and catheter-tip movement during aneurysm embolization. Thus, the generation pattern of coil insertion force was investigated and the most suitable insertion method and speed were discussed.
Methods: A new sensor device which consists of a Y-connector was developed. The sensor principle is based on an optical system measuring how much the coil-delivery wire slightly bends in response to the insertion force. Using this device, experimental coil embolizations were performed with silicone aneurysm models. The manipulations were done by hand or by machine at a constant speed. The sensor continuously monitored the mechanical force during the insertions. The coil movement was observed on a microscopic image. The pattern of coil insertion force and the time distribution ratio of the force were analyzed.
Result: With manual insertion, the coil insertion force was mainly induced by the stop and advance movement of the wire generated in synchrony with the push-pull-push movement of the surgeon's hand. With mechanical insertion, the insertion speed caused a difference in the force pattern. With the coil movement, the friction between the coil and aneurysm wall was determined by insertion method and insertion speed. Thus, the friction state (static friction or kinetic friction) affected the mechanical force.
Conclusion: It was demonstrated that the friction state influenced the generation pattern of coil insertion force. Applying the proper insertion method and insertion speed to maintain the kinetic friction state between the coil and the aneurysm wall might provide less stressful coil insertion force and safer embolization.

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Purpose: To evaluate treatment outcome of P2-segment aneurysms of the posterior cerebral artery by coil embolization.
Subjects: Seven patients (three with subarachnoid hemorrhage due to ruptured aneurysms and four with unruptured ones) underwent endovascular treatment. 4 patients presented with unruptured aneurysms, 1 presented with mass effect, 1 was associated with another ruptured cerebral aneurysm, and 2 were diagnosed during a routine examination for headache.
Results: Endosaccular coil embolization was performed for the saccular aneurysms (3 ruptured and 2 unruptured cases) and parent vessel occlusion was performed for the fusiform aneurysm (1 unruptured case) and thrombosed aneurysm (1 unruptured case). No apparent complications were noted perioperatively or during the follow-up periods of 2 years to a maximum of 5 years and 5 months, average: 3.6 years. Retreatment was not required for any case.
Conclusion: Outcomes of endovascular treatments for P2-segment aneurysms of the posterior cerebral artery were good. If endosaccular coil embolization is not possible, it is advisable to evaluate collateral circulation with an occlusion test, checking the presence of neurological ischemic symptoms, and perform parent artery occlusion. However, each case requires individual consideration.

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Objectives: Small aneurysmal size is a risk factor for procedure-related rupture during coil embolization and the treatment of small aneurysms is still controversial. We evaluated 13 small aneurysms treated by coil embolization, and discussed the technical aspects, safety and angiographic follow-up outcomes of the treatment. Moreover, the volume rate and duration of procedures were evaluated comparing the treatment with only Guglielmi detachable coil (GDC) and the treatment with newer coils with or without GDC.
Methods: Between February 2005 and February 2009, 97 aneurysms were embolized with coils. Of those 97 aneurysms, thirteen small aneurysms with a maximum diameter of 3mm were found in twelve patients and included in this study. These aneurysms comprised 8 ruptured and 5 unruptured aneurysms. Treatment outcome, procedure-related complications and completeness of occlusion during the follow-up period were investigated in relation to the kind and characteristics of the coils.
Results: All 13 small aneurysms could be embolized. Follow-up period was 22.8 months. Complications were one procedure-related rupture and one thrombo-embolism. There was no rupture of occluded aneurysms during the follow-up period. Of the 13 aneurysms, 5 were completely occluded, and 8 were incompletely occluded on the angiogram just after the procedure. Incompletely-occluded 4 aneurysms showed progression to complete occlusion on the follow-up angiogram. The mean duration of procedure was reduced and the mean volume embolization rate increased when embolized with newer coils than GDC.
Conclusions: Although endovascular coil embolization of small aneurysms still holds a high risk of procedure-related rupture, the technical and material improvement has enabled us in the last few years to treat them more safely and simply.

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Objective: We report a case of intracranial pial arteriovenous fistula (pial AVF) with a giant varix completely obliterated by endovascular treatment.
Case presentation: A 17-year-old man presented with mild left hemiparesis and dizziness. Cerebral angiography revealed an intracranial pial AVF with a giant varix arising from the right middle cerebral artery (MCA). By transarterial approach through the fistula into the varix, detachable coils were placed in the varix and the right MCA just proximal to the fistula. This strategy preserved the normal branches of the right MCA arising about 10 mm proximal to the fistula. We then injected n-butyl cyanoacrylate. The pial AVF was obliterated after applying these procedures.
Conclusion: Endovascular treatment is an effective and valuable alternative treatment for patients with pial AVF when a surgical approach is difficult.

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