One of the most important problems for stroke patients is nutritional management. Malnutrition results in poor prognosis with many complications. Many patients with consciousness disturbance and dysphagia undergo enteral nutrition. PEG facilitates a smooth rehabilitation and increases QOL.

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We compared medical expenditure, length of hospital day, complications and intensity of clinical services during hospitalization for carotid endarterectomy (CEA) before, during and after the 2003 implementation of DPC-based PPS, which pays a fixed fee per discharge diagnosis. The medical expenditure during hospitalization for CEA was generally higher under DPC-based PPS, though the difference was only about 10%. The length of hospital day, sorts and number of examinations affected the costs somewhat, but there were no remarkable differences within ordinary perioperative course or with routine examinations. The situation should change with the spread and the revision of DPC-based PPS and medico-economic aspects may come to weigh much in the choice of examinations and treatments for carotid stenosis.

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We focused on complicated carotid lesions in 324 of our carotid endarterectomies (CEAs) to clarify controversies in carotid surgeries. Carotid lesions extented to the C2 level in over 20% of lesions. Bilateral stenotic lesions were operated in 22 cases without problems. Nine of 15 contralateral occlusion cases were supported with STA-MCA anastomosis indicated by the CBF. In near-occlusion cases, distal sites of lesions were detected by IVUS. Restenosis was observed in 9 cases. Only 1 restenotic case was symptomatic and 4 restenotic cases were reoperated with patch graft. Hemashield patch grafts were used in 18 cases and no restenotic changes were observed. Intracranial aneurysm was seen in 12 cases and 7 cases were clipped before CEA. Hyperperfusion syndrome was seen in 6 cases. Two cases showed intracerebral hemorrhage resulting in postoperative neurological deficits. Symptomatic occlusive coronary lesions were seen in 62 cases and surgical or intravascular treatment or both were performed in 30 cases.
Guidelines for CEA have been established by randomized controlled trails, but some cases have very complicated clinical features such as multiple lesions. For these cases, safer and more effective strategies should be established by collaborative studies.

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We evaluated our treatment protocol and results on the intraaneurysmal GDC embolization for ruptured aneurysm in the acute stage.
Between 1998 and 2002, 55 aneurysms were treated by intraaneurysmal embolization and 252 aneurysms were treated by surgical neck clipping. Patients with ruptured aneurysm were always considered possible candidates for surgical clipping. If the patients had any difficulties and/or problems on surgical clipping, the patients were treated by intraaneurysmal embolization.
In the intraaneurysmal embolization group, 2 patients were classified as Hunt & Kosnik Grade 1, 23 as Grade 2, 19 as Grade 3, 10 as Grade 4 and 1 as Grade 5. Nineteen aneurysms were located on the ICA, 10 on the AcomA, one on the ACA, 3 on the MCA, 3 on the VA and 19 on the BA. In the neck clipping group, 13 patients were classified as Grade 1, 123 as Grade 2, 80 as Grade 3, 32 as Grade 4 and 4 as Grade 5. Sixty-nine aneurysms were located on the ICA, 69 on the AcomA, 13 on the ACA, 67 on the MCA, 9 on the VA, 5 on the BA and 3 at other locations. Symptomatic vasospasm occurred in 2 cases (3.6%) in the intraaneurysmal embolization group and in 13 cases (5.2%) in the neck clipping group. Rebleeding within 3 months after treatment occurred in 1 case (1.8%) in the intraaneurysmal embolization group and in 4 (1.6%) cases in the neck clipping group. The modified Glasgow Outcome Scale (GOS) grade at discharge showed that 44 patients (80.0%) had good outcome (GR or MD) in the intraaneurysmal embolization group, and that 213 patients (84.5%) had good outcome in the surgical neck clipping group.
Intraaneurysmal embolization for cases with surgical difficulties and/or problems was useful and may raise overall outcome.

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Although stereotactic radiosurgery has been recognized as an effective treatment modality for cerebral arteriovenous malformations (AVMs), its long-term outcome after more than 10 years is still unknown. We retrospectively analyzed the complications arising long after radiosurgery for AVMs. Five-hundred patients with AVMs were treated with radiosurgery and were followed at the University of Tokyo hospital. The mean age was 31 years and the mean dose delivered to the AVM margin was 21.0 Gy. The mean diameter of AVMs was 1.9 cm. Radiation-induced neurological complications were observed in 5.2% of patients and could be reduced with recent improvements in imaging technique. Hemorrhage during the interval between radiosurgery and obliteration was observed in 23 out of 500 patients and after confirmation in 6 out of 250 patients. After radiosurgery, the risk of hemorrhage was decreased by 54% during the interval between radiosurgery and angiographic obliteration, and a small risk of hemorrhage remained even after obliteration. Delayed cysts developed in 3 out of 6 patients at the site of previous hemorrhage. The cyst spontaneously decreased in 1 patient and increased in another, requiring surgical resection. Delayed cyst formation unrelated to hemorrhage was also observed in 2 patients, which were closely observed.
Angiographic obliteration after radiosurgery for AVM is not necessarily equal to long-term cure because residual degenerated nidus might cause hemorrhage or delayed cyst formation. Radical treatments such as surgical excision of the nidus should be used for respectable lesions and cystoperitoneal shunt or placement of Ommaya reservoir should be selected for unresectable cystic lesions.

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We respectively evaluated the effectiveness of low-dose gamma knife surgery (GKS) for small cerebral arteriovenous malformations (AVMs) in Chiba Cardiovascular Center. One-hundred consecutive cases with small (<10 cc) AVM treated with ≤20 Gy at the periphery were analyzed. The survival curves for angiographical complete occlusion, radiation-induced edema and latency period bleeding were calculated by the Kaplan-Meier method, and the prognostic values of 9 covariates were obtained. The complete obliteration rate at 4 years was 91.6%. On multivariate analysis, the only significant prognostic factor was peripheral dose (p=0.0101). Radiation-induced edema was observed in 62.7%. Seven cases (12.5%) developed minor transient symptoms. The only permanent delayed radiation injury was cyst formation in 1 case. The significant prognostic factors for radiation-induced edema were peripheral dose (p=0.0387) and nidus volume (p=0.0161). Bleeding during the latency period was relatively rare (2.0%).
In conclusion, our low-dose GKS using ≤20 Gy at the periphery provides excellent results for small AVMs.

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We reviewed 84 AVMs embolized over 7 years and studied the significance of the embolization for associated aneurysms. Out of 84 AVMs, 14 were preoperatively embolized and 66 were followed by radiosurgery. Ten intranidal aneurysms were found in 9 cases, all of which ruptured. Although 8 aneurysms were completely embolized, using glue, 2 incompletely treated aneurysms rebled. Out of 6 proximal feeder aneurysms, 3 ruptured ones were treated with detachable coils and have shown no rebleeding. The other 3 aneurysms that increased in size during the follow-up after the embolization of AVM were embolized without complications. Two flow-related aneurysms remained, and an AVM nidus was primarily treated. Both aneurysms disappeared after the embolization of AVM.
The ruptured proximal feeder aneurysms located far from the nidus, which require another approach for the removal of AVM, should be embolized with coils to reduce surgical invasiveness. Embolization of intranidal aneurysms is very useful for the prevention of rebleeding, particularly in cases followed by radiosurgery.
Among the flow-related aneurysm treatments, AVM may be the treatment of choice. As for the treatment strategy of AVM, it is important to detect and identify the associated aneurysms and treat them appropriately.

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The incidence of carotid artery stenosis is debatable based upon the findings of the NASCET, ECST and ACAS reports. We generally determine the incidence of stenosis in patients through the limited directions by angiographic methods. However, there are likely some shortcomings of this evaluation procedure with the pathogenesis of carotid artery stenosis.
The importance of the carotid artery wall has recently been established. In general, these characteristics can be examined using ultrasound sonography. While the degree of ulceration, endothelial condition, lipid pool, thin cap and plaque intensity can ordinarily be examined, we are especially attempting to detect the existence of neovascularization in plaque. The importance of neovascularization in atherosclerosis has been recognized. Neovascularization is one of the pathological factors introducing plaque hemorrhage and rupture, which can result in carotid artery occlusion and artery-to-artery embolism.
Pulse inversion harmonic image (PIHI) using pulse inversion to eliminate and strengthen the harmonic frequency is more effective than conventional harmonic imaging. We can detect a tissue perfusion by contrast sonographic imaging with PIHI, and its clinical application has already been reported. Consequently, we use this method to test for cardiac infarction, liver tumor, brain tumor and cerebrovascular diseases.
We examined carotid artery wall perfusion (CAWP) and the rule of neovascularization within the plaque by this method.
The routes of vascular wall feeding are as follows:
1) Luminal diffusion feeds the vascular wall from the endothelium to the inner part of the medium and 2) the vasa vasorum feeds it from the adventitia to the outer part of the medium. Consequently, neovascularization does not occur at the former vascular wall region. However, some plaque is resistant to neovascularization.
As a result, we attempt to detect plaque using this method, and we have already described a classification of CAWP findings.
Type I exhibits no perfusion and lack of neovascularization.
Type II exhibits partial perfusion of CAWP that is indicative of mild neovascularization.
Type III exhibits multiple perfusion of CAWP that is indicative of moderate neovascularization.
Type IV exhibits general perfusion of CAWP that is indicative of neovascularization of the whole plaque. Type III and IV are usually observed in patients with intramural hemorrhage or artery-to-artery embolism.
We propose the following mechanism for plaque development.
The beginning of atherosclerosis→in some, neovascularization on the plaque development→The small neovasculature is vulnerable. Consequently, damage can occur by mechanical stimulation→then intramural hemorrhage can occur→resulting in the onset of ischemic symptoms as the development of stenosis or embolism.
We intend to examine the incidence of carotid artery stenosis with or without neovascularization and carefully observe such patients because of the rapid development of plaque, plaque rupture, occlusion of main extracranial arteries and artery-to-artery embolism.

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Purpose: We experimentally assessed the pitfalls of distal balloon protection systems to learn technique tips for safe procedures.
Materials and methods: Silicone carotid artery models were connected to a circulatory system to simulate carotid bifurcation. A distal balloon protection device, PercuSurge GuardWire Plus (PSGWP, Medtronic Vascular) was navigated to the internal carotid artery (ICA) and inflated to occlude ICA flow temporarily. A debris aspiration catheter (Thrombuster, Kaneka Medics) was navigated just proximal to the PSGWP coaxially to introduce and diffuse particulate debris (200-500 micro meter in diameter) in the ICA stump. After debris in the stump was aspirated, the PSGWP was deflated. We recorded all the processes of our simulation experiments on a digital video and observed the movements of debris during these experiments.
Exp 1) We simulated the movements of debris in the ICA stump when the PSGWP balloon was gradually deflated to produce a gap between the balloon and vessel wall, simulating accidental movement of the PSGWP balloon during the procedure. Exp 2) To assess the optimal placement of the tip of aspiration catheter, the debris in the ICA stump was aspirated from 3 different sites (from just below the GuardWire balloon, from 5 cm below it, and at the ICA orifice). Exp 3) To assess the capacity of the aspiration catheters (7F, 6F Thrombusters (Kaneka Medics), 5.4F Export catheter (Medtronic Vascular), we compared the time to aspirate 20 cc of normal saline.
Results: Exp 1) When the gap appeared between PSGWP balloon and silicone tube, simulated debris began to concentrate just below the balloon. Then, some debris migrated distally from the gap, and other debris crowded in the gap so that it was impossible to aspirate and migrated. Exp 2) Debris aspiration was most effective from immediately below the PSGWP, and the aspiration ability declined as the distance between the balloon and aspiration catheter became longer. Exp 3) The aspiration time for 20 cc of normal saline is 8.4+/-0.2 sec, 12.8+/-0.5 sec, 13.3+/-0.1 sec. in case of 7F Thrombuster, 5.4F Export catheter, 6F Thrombuster, respectively.
Conclusion: Our simulation studies show that when the PSGWP was moved accidentally during CAS procedures, or when the aspiration catheter was not delivered all the way to the PSGWP balloon, distal embolization might still occur, even when care is taken. So to protect the distal embolism, the PSGWP balloon should be fully dilated and fixed to the arterial wall during procedures, and the aspiration catheter should be navigated just proximal to the PSGWP balloon.

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A 25-year-old right-handed woman presented with sudden-onset aphasia and right hemiparesis. She was restless, and her GCS score was E4V1M5 on admission. Diffusion-weighted MRI showed high intensity areas in the left insular cortex, frontal lobe, and corona radiata. Perfusion CT showed a large hypoperfusion area almost identical to the left MCA distribution. Cerebral angiography disclosed occlusion of the left internal carotid artery bifurcation. Emergency superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis was performed.
She showed progressive recovery in verbal function following surgery, and reached a GCS score of E4V4M6 at Day 3. Postoperative perfusion CT confirmed restoration of cerebral blood flow in the left MCA distribution. She became ambulatory with a cane 2 months later.
In spite of thorough examination, the cause of the internal carotid artery occlusion remains unclear. STA-MCA anastomosis in the acute stage may be beneficial in neurological recovery in a selected group of patients with intracranial internal carotid artery occlusion.

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We report a case of 74-year-old man with a recurrent subarachnoid hemorrhage (SAH) caused by a de novo aneurysm. He suffered from SAH due to a ruptured aneurysm at right middle cerebral artery (MCA) bifurcation and had a neck clipping surgery of the aneurysm. At that time a 4-vessel-angiography revealed no aneurysm at left MCA. One year and 2 months after a clipping, he suffered from cerebral infarction and underwent an angiography again. The second angiography showed a small bulge at left MCA. But we could not recognize it at that time. He suffered from recurrent SAH about 16 months after the first episode. The third angiography revealed a distinct aneurysm at left MCA trifurcation. The aneurysm had newly developed within only 1 year and 2 months and rapidly grown up to rupture for 6 weeks. In this case we recognized hypertension and cigarette smoking as risk factors of de novo aneurysm, and the de novo aneurysm developed at a mirror site, a common site of de novo aneurysm. It is very important for patients with a prior SAH to manage these risk factors.

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