Management of Cervical Internal Carotid Artery Stenosis or Occlusion in Tandem Lesion with Acute Ischemic Stroke: Which Is More Appropriate Percutaneous Transluminal Angioplasty or Stent?

OBJECTIVE: Carotid artery stenting (CAS) is the established treatment strategy of the cervical internal carotid artery (cICA) stenosis, but its use for acute tandem lesions remains controversial. We investigated the clinical and procedural outcomes of management of cICA lesions and evaluated the risk factors for complications. METHODS: Fifty patients who underwent acute mechanical thrombectomy for tandem lesion between January 2014 and June 2022 were included. Treatment of the cICA lesion was classified into the CAS group or the non-CAS group. The risk factors for postoperative ischemic events or symptomatic intracranial hemorrhage (sICH) were analyzed. RESULTS: The CAS group included 36 patients (72%) and the non-CAS group 14 (28%). Postoperative complications were observed in 9 patients (18%). Thromboembolic complications occurred in 4 patients (29%) of the non-CAS group but in 1 patient (3%) of the CAS group. Severe calcification of the cICA (P = 0.04), non-CAS (P = 0.018), and more than 60% residual stenosis (P = 0.016) were significant risk factors associated with thromboembolic complications. sICH occurred in 4 patients (11%) of the CAS group but in none of the non-CAS group. More than 80% stenosis improvement was significantly associated with sICH (P = 0.049). Twenty-nine patients (58%) had a good clinical outcome at 90 days after onset. CONCLUSIONS: Acute CAS is effective for the management for cICA tandem lesions during mechanical thrombectomy, but care not to overextend may be important to reduce the risk of sICH. Severe calcification of the cICA may increase the risk of postoperative thromboembolic complications using non-CAS treatment.

A case of craniocervical junction pial arteriovenous fistula causing postoperative medullary and spinal cord edema.

OBJECTIVES: Pial arteriovenous fistulas (pAVFs) are direct connections between the pial artery and vein without an intervening nidus. We report a rare case of craniocervical junction (CCJ) pAVF causing medullary and spinal cord edema resulting from surgical removal of the varix with remnant shunt after coil embolization. CASE DESCRIPTION: A 16-year-old man presented with subarachnoid hemorrhage. Digital subtraction angiography revealed a CCJ pAVF with multiple fistulas at the 2 varices (varix A and varix B), which was fed by the bilateral lateral spinal arteries and anterior spinal artery (ASA), and drained into the median posterior vermian vein with varix (varix C) and anterior spinal vein (ASV). Varices A and B were embolized using coils, but the shunts remained in varix C. Then, varix C was surgically removed. After this operation, medullary and spinal cord edema occurred. Digital subtraction angiography showed the ASV drainage responsible for edema. Finally, surgical removal of varices A and B was performed. However, arteriovenous shunts, supplied by the ASA and drained into the ASV via the intrinsic vein, were found in the medulla oblongata and coagulated, resulting in disappearance of edema. CONCLUSIONS: Edema was probably caused by concentration of drainage from the arteriovenous shunt in the medulla oblongata into the ASV by surgical removal of varix C acting as another draining route. High flow AVF can induce angiogenesis and secondary arteriovenous shunt. Precise analysis of the angioarchitecture is important to treat such cases without complications.

Long-Term Durability and Recurrence Patterns After Endovascular Treatment for Basilar Tip Aneurysms.

BACKGROUND: Treating recurrence after coil embolization of basilar tip aneurysm remains challenging even with the development of endovascular procedures. The present study evaluated long-term durability and recurrence patterns after endovascular treatment of basilar tip aneurysms. METHODS: Data of 116 consecutive patients treated with endovascular therapy at 3 regional hospitals from 2002-2019 were retrospectively analyzed. Aneurysms were ruptured in 51 cases and unruptured in 65 cases, with a mean maximal diameter of 7.8 mm (>15 mm in 14 patients) and a mean follow-up period of 5.8 ± 4.3 years. RESULTS: Recurrence was observed in 24 of the 116 patients (21%), and 14 patients were retreated. The 5-year recurrence-free survival rate was 75.3%. Cox proportional hazards analysis found that recurrence correlated significantly with maximal aneurysm diameter >10 mm (P = 0.001; hazard ratio: 3.95, 95% confidence interval: 1.76-8.90) and incomplete occlusion (P = 0.003; hazard ratio: 4.43, 95% confidence interval: 1.63-12.00). Recurrence pattern was classified into 3 types: neck type (9 patients), regrowth type (10 patients), and regrowth type of initially thrombosed aneurysms (3 patients). Rerupture occurred in neck type with de novo aneurysm formation adjacent to the neck (n = 3) and regrowth type with dome filling (n = 4). CONCLUSIONS: Recurrence after coil embolization for basilar tip aneurysms is associated with large aneurysms and incomplete occlusion at initial embolization. Understanding the patterns of recurrence is useful for predicting recurrence and selecting treatment strategies.

Analysis of the Pial Arterial Supply as a Cause of Intraprocedural Hemorrhage During Transarterial Liquid Embolization of Tentorial Dural Arteriovenous Fistulas.

OBJECTIVE: Tentorial dural arteriovenous fistulas (AVFs) are bridging vein shunts, and are therefore sometimes supplied by the pial artery as well as the dural artery. Recently, intraprocedural hemorrhage from the pial artery was reported, and we experienced 2 tentorial dural AVFs with the same complication. Pure pial artery has a glomus-like structure and forms direct shunts along the draining vein, and is likely to bleed after restriction of the draining vein caused by the transarterial embolization. This study investigated the characteristics of the pial arterial supply as a cause of hemorrhage. METHODS: Twenty-six tentorial dural AVFs in 25 patients treated in our institute were retrospectively investigated and the characteristics of the pial feeders responsible for bleeding were analyzed. RESULTS: Thirteen pial arterial feeders (pure pial feeder in 7, dilated dural branch of the pial artery in 4, and undefined in 2) were identified in 10 of the 26 tentorial dural AVFs. Pure pial feeders were responsible for bleeding in 2 tentorial dural AVFs. CONCLUSIONS: To prevent intraprocedural hemorrhage, differentiation of the pure pial supply from the dural branch of the pial artery is important. The infratentorial artery will supply supratentorial fistula as the dural branch after passing through the tentorium. In contrast, the supratentorial artery can supply supratentorial fistula not only as a dural branch but also as a pure pial feeder. Therefore, attribution of the fistula and the pial supply, supratentorial or infratentorial, is useful in identifying pure pial supply.

Recurrent Lobar Hemorrhages and Multiple Cortical Superficial Siderosis in a Patient of Alzheimer's Disease With Homozygous APOE ε2 Allele Presenting Hypobetalipoproteinemia and Pathological Findings of 18F-THK5351 Positron Emission Tomography: A Case Report.

In Alzheimer's disease, the apolipoprotein E gene (APOE) ε2 allele is a protective genetic factor, whereas the APOE ε4 allele is a genetic risk factor. However, both the APOE ε2 and the APOE ε4 alleles are genetic risk factors for lobar intracerebral hemorrhage. The reasons for the high prevalence of lobar intracerebral hemorrhage and the low prevalence of Alzheimer's disease with the APOE ε2 allele remains unknown. Here, we describe the case of a 79-year-old Japanese female with Alzheimer's disease, homozygous for the APOE ε2 allele. This patient presented with recurrent lobar hemorrhages and multiple cortical superficial siderosis. The findings on the 11C-labeled Pittsburgh Compound B-positron emission tomography (PET) were characteristic of Alzheimer's disease. 18F-THK5351 PET revealed that the accumulation of 18F-THK 5351 in the right pyramidal tract at the pontine level, the cerebral peduncle of the midbrain, and the internal capsule, reflecting the lesions of the previous lobar intracerebral hemorrhage in the right frontal lobe. Moreover, 18F-THK5351 accumulated in the bilateral globus pallidum, amygdala, caudate nuclei, and the substantia nigra of the midbrain, which were probably off-target reaction, by binding to monoamine oxidase B (MAO-B). 18F-THK5351 were also detected in the periphery of prior lobar hemorrhages and a cortical subarachnoid hemorrhage, as well as in some, but not all, areas affected by cortical siderosis. Besides, 18F-THK5351 retentions were observed in the bilateral medial temporal cortices and several cortical areas without cerebral amyloid angiopathy or prior hemorrhages, possibly where tau might accumulate. This is the first report of a patient with Alzheimer's disease, carrying homozygous APOE ε2 allele and presenting with recurrent lobar hemorrhages, multiple cortical superficial siderosis, and immunohistochemically vascular amyloid ß. The 18F-THK5351 PET findings suggested MAO-B concentrated regions, astroglial activation, Waller degeneration of the pyramidal tract, neuroinflammation due to CAA related hemorrhages, and possible tau accumulation.

Endovascular Treatment Strategy and Clinical Outcomes for Ruptured Blood Blister-Like Aneurysms of the Internal Carotid Artery Using Low-Profile Visualized Intraluminal Support Stent.

OBJECTIVE: It is challenging to safely treat blood blister-like aneurysms (BBAs) of the internal carotid artery. Endovascular surgery has been reported, but the optimal strategy is yet to be established. We report our endovascular treatment strategy using the Low-profile Visualized Intraluminal Support (LVIS) stent. METHODS: Twelve patients with ruptured BBAs including 1 patient with 2 separate aneurysmal bulges were treated from December 2017 to January 2020. Single LVIS stent-assisted coil embolization was performed as the initial treatment. If the coil could not be placed in the aneurysm, or follow-up angiography showed persistent filling or regrowth of the aneurysm, a second LVIS stent was deployed as an overlapping stent. Clinical characteristics, treatment details, and clinical outcomes were retrospectively examined. RESULTS: Single stent-assisted coiling was performed in 8 patients (69%), 2 overlapping stents with coiling in 1 (8%), a single stent in 2 (15%), and 2 overlapping stents in 2 (15%). Three patients with persistent filling or regrowth of the aneurysm were re-treated with overlapping stents. Follow-up angiography confirmed complete occlusion in 12 aneurysms (92%). No re-rupture occurred. Postoperative symptomatic ischemia was confirmed in 4 patients (33%), and all 4 patients suffered severe subarachnoid hemorrhage. Modified Rankin scale was 0-2 in 8 patients (67%). CONCLUSIONS: LVIS stent-assisted coil embolization is effective in preventing re-rupture of BBAs. However, the morphology of the aneurysm may change within a short period, so careful angiographic follow-up is needed. Appropriate preoperative antiplatelet administration and optimal timing of the treatment may reduce the risk of postoperative ischemic complication.

Successful basilar artery dilatation in pure bilateral cerebral peduncular infarctions using balloon angioplasty.

•An extremely rare case of bilateral cerebral peduncular infarctions (BCPI) is reported.•The detection of the pure Mickey Mouse ears sign on MRI is an indicator of a need for reperfusion therapy.•Severe stenosis of the basilar artery (BA) and a poor collateral supply from both posterior cerebral arteries were seen.•Balloon angioplasty for the BA stenosis ameliorated the stenosis and produced a favorable outcome.

Surgical Strategies and Clinical Results of Site-Specific Treatment Using High-Flow Bypass for Ruptured Blood Blister-Like Anterior Wall Aneurysms of the Internal Carotid Artery.

OBJECTIVE: Surgical treatment of ruptured blood blister-like aneurysms (BBAs) arising from the internal carotid artery (ICA) is challenging. We retrospectively reviewed the results of our surgical strategies tailored for each aneurysm site. METHODS: All ruptured ICA BBAs treated between 2003 and 2015 were reviewed. Aneurysms on the lateral side of the ICA were classified as type A, on the medial side of C2 as type B, and on the medial side of C1 as type C. The principal strategy was high-flow bypass (HFB) by use of a radial artery graft, with clipping, trapping, or proximal occlusion selected on the basis of aneurysm type. The results of each treatment were examined. RESULTS: This study included 20 patients. There were 11 type A aneurysms (55%), 2 type B (10%), and 7 type C (35%). HFB was used in 13 patients (65%) and low-flow bypass in 4 (20%). Except for 1 case, no other cases of rerupture or recurrence occurred. Severe ischemia due to cerebral vasospasm was confirmed in 4 of 20 patients (20%), 3 of whom had not received HFB. Modified Rankin Scale score was 0-2 in 16 of 20 patients (80%). CONCLUSION: Inadequate cerebral blood flow is a distinct possibility even with HFB, so parent artery flow should be preserved to protect against ischemia whenever possible. However, if preservation of the anterior choroidal artery or posterior communicating artery during clipping or trapping is difficult, HFB combined with occlusion of the proximal portion of the ICA in the neck is a feasible option.

Adult moyamoya disease associated with abundant phosphorylated tau accumulation in the brainstem: Report of a case with autopsy findings.

We report the case of a 72-year-old Japanese woman with moyamoya disease (MMD). She experienced her first intracerebral hemorrhage (ICH) at the age of 32 years, and had nine ICHs and/or intraventricular hemorrhages during the following 40 years. Cerebral angiograms and vascular pathologies at autopsy confirmed that the patient suffered from MMD. Macroscopically, there were brown-colored changes in the subarachnoid space, mainly at the base of the brain and around the cerebellar hemispheres. Microscopically, hemosiderin deposits were observed mainly in the old hemorrhagic lesions and on the surface of the brainstem and cerebellum. Many AT8-immunoreactive neurons and neurites were observed in the pons and midbrain, mainly in the locus ceruleus and reticular formation in the midbrain. Several AT8-immunoreactive neurons and neurites were positive for Gallyas silver staining. A few tiny and short AT8-immunoreactive processes were observed in the molecular, Purkinje cell and granular layers of the cerebellum. There were a few phosphorylated tau accumulations in the cerebrum without senile plaques. Lewy pathologies and transactive response DNA-binding protein 43 kDa proteinopathy were not detected. We suspect that oxidative stress after repeated bleedings with long-term courses in the ventricles and subarachnoid space may accelerate phosphorylated tau accumulation in the brainstem. To our knowledge, this is the first report of MMD with tauopathy in the brainstem.

Predictive factors of medullary infarction after endovascular internal trapping using coils for vertebral artery dissecting aneurysms.

OBJECTIVE The first choice of treatment in cases of vertebral artery dissecting aneurysms (VADAs) is endovascular internal trapping (EIT) of the dissecting segment using coils. However, this procedure carries the risk of medullary infarction, and the risk factors for this complication are not well understood. This study investigated the risk factors causing medullary infarction. METHODS One hundred patients who underwent EIT for VADAs were included in this study. Ninety-three patients presented with subarachnoid hemorrhage. In cases involving the posterior inferior cerebellar artery (PICA), partial internal trapping targeting the ruptured site was performed to preserve the PICA. The VADAs were classified into the distal VA stump group, proximal VA stump group, and entire VA stump group, according to the location of VA segments without adequate flow-out vessels (such as the PICA [VA stump]) at risk of delayed thrombosis. The occurrence of medullary infarction was examined in each group using diffusion-weighted MRI and/or clinical symptoms. Various measurements were performed on digital subtraction angiography, and the risk factors for medullary infarction were analyzed. RESULTS Medullary infarction occurred in 30 patients, affecting the posterolateral medulla in 27 patients and the anteromedial medulla in 3 patients. Medullary infarction occurred in 3 of 47 patients (6%) in the distal VA stump group, 10 of 19 patients (53%) in the proximal VA stump group, and 17 of 34 patients (50%) in the entire VA stump group. The length of trapping was significantly longer in the infarction group than in the noninfarction group but did not differ among the 3 groups. Total length (length of trapping plus VA stump) was a risk factor for medullary infarction in the proximal VA stumps. CONCLUSIONS The primary risk factor for medullary infarction after EIT is not the length of trapping; rather, it is the anatomical location of the VADAs. The risk of medullary infarction is low in cases with distal VA stumps, but the symptoms are severe. Preservation of the origin of the anterior spinal artery can reduce the risk of medullary infarction. The risk of medullary infarction is high in cases with proximal VA stumps, but the symptoms are mild. A shorter length of trapping, although less likely to lead to complications, cannot prevent medullary infarction because the total length depends on the anatomical location of the PICA and not on the surgical technique. Reconstructive therapy should be indicated for patients with ruptured VADAs at high risk of severe ischemic complications (e.g., patients with hypoplasia of the contralateral VA or cases involving the PICA or anterior spinal artery, which are inappropriate for partial internal trapping) or for patients with unruptured VADAs.

Preoperative embolization of intracranial meningiomas using n-butyl cyanoacrylate.

INTRODUCTION: Preoperative embolization for intracranial meningioma has been controversial for several decades. This study retrospectively reviewed our experience using n-butyl cyanoacrylate (n-BCA) to identify the factors for effective devascularization and procedure-related complications. METHODS: Fifty-seven patients who underwent preoperative embolization with n-BCA were analyzed to collect the following data: age, sex, tumor size, location, pathology, and presence or absence of pial arterial supply. The predictive factors for total devascularization and complications were examined using univariate and multivariate analyses. RESULTS: Injected n-BCA penetrated into the tumor vessels in 51 cases (89%) but resulted in feeder occlusion in 6 (11%). Angiographic total devascularization was achieved in 29 cases (51%) and partial devascularization in 28 (49%). Small size, superficial location, and absence of pial supply were independent factors for total devascularization. No major complication was encountered, but asymptomatic or transient adverse events occurred in nine patients and were significantly associated with elderly patients and large tumors. CONCLUSION: Preoperative embolization for intracranial meningiomas using n-BCA can attain effective devascularization without major complications. The effect of preoperative embolization on surgical resection or patient outcome is still unknown.

Efficacy and limitations of transarterial acrylic glue embolization for intracranial dural arteriovenous fistulas.

The efficacy and limitations of transarterial acrylic glue embolization for the treatment of intracranial dural arteriovenous fistulas (DAVFs) were investigated. Thirty-four DAVFs treated by transarterial embolization using n-butyl cyanoacrylate were retrospectively reviewed. The locations of DAVFs were the transverse-sigmoid sinus in 11, tentorium in 10, cranial vault in 9, and superior sagittal sinus, jugular bulb, foramen magnum, and middle cranial fossa in 1 each. Borden classification was type I in 7, type II in 3, and type III in 24. Eight patients had undergone prior transvenous coil embolization. Complete obliteration rate was 56% immediately after embolization, 71% at follow-up angiography, and 85% after additional treatments (1 transvenous embolization and 4 direct surgery). Complications occurred in three patients, consisting of asymptomatic vessel perforations during cannulation in two patients and leakage of contrast medium resulting in medullary infarction in one patient. Transarterial glue embolization is highly effective for Borden type III DAVF with direct cortical venous drainage, but has limitations for Borden type I and II DAVFs in which the affected sinus is part of the normal venous circulation. Onyx is a new liquid embolic material and is becoming the treatment of choice for DAVF. The benefits of glue embolization compared to Onyx embolization are high thrombogenicity, and relatively low risks of cranial nerve palsies and of excessive migration into the draining veins of high flow fistula. Transarterial glue embolization continues to be useful for selected patients, and complete cure can be expected in most patients with fewer complications if combined with transvenous embolization or direct surgery.

Visual outcomes of endovascular and microsurgical treatment for large or giant paraclinoid aneurysms.

BACKGROUND: The optimal treatment for large or giant paraclinoid aneurysms is still controversial. The present study evaluated the results of endovascular coiling and microsurgical clipping with special reference to visual outcomes. METHODS: The clinical data and treatment outcomes of 39 cases of large (>15 mm) paraclinoid aneurysms were retrospectively reviewed. Presenting symptoms were subarachnoid hemorrhage in 16 aneurysms and visual impairment in 18. Twenty-one aneurysms were treated by endovascular therapy and 18 were treated by direct surgery. RESULTS: Maximal aneurysm diameter ≥25 mm and preoperative visual acuity <20/100 were significantly related to poor visual outcome in univariate analysis. However, preoperative visual acuity was the only significant prognostic factor in multivariate analysis (odds ratio [OR] 0.12, 95 % confidence interval [CI] 0.01-0.95, p = 0.04). Although patients treated with endovascular coiling tended to have more favorable outcome than those with surgical clipping, adjustment for other confounding factors reduced the OR of favorable outcome following each treatment modality to nearly one (OR 1.14, 95 % CI 0.17-7.46, p = 0.89). Deteriorations in the visual field showed different patterns: upper visual field deficit after endovascular coiling, and inferior nasal quadrantanopia after microsurgical clipping. CONCLUSIONS: Preoperative visual acuity was the only independent predictor of visual outcome in patients with large paraclinoid aneurysms. Although adjusted visual outcomes with microsurgical clipping and endovascular coiling were almost the same, selection of the optimal treatment for each aneurysm is essential with recognition of the potential risks and mechanisms of visual impairment.

Spinal epidural arteriovenous fistulas with unusual manifestation of sudden onset of severe neurological deficits: case report.

Spinal epidural arteriovenous fistulas with perimedullary venous drainage cause venous hypertension, and usually manifest as slowly progressive myelopathy. We treated two patients presenting with sudden onset of severe neurological deficits. Moreover, in Case 1, the venous drainage was exclusively epidural and no perimedullary venous drainage was present. Angiographic findings of this patient were characterized by a slow-flow fistula with marked retention of the epidural venous drainage. Rapidly progressing thrombosis of the epidural venous plexus may have caused the sudden onset of the symptoms. In Case 2, hematomyelia may also be possibly associated with the sudden onset of the symptoms. Early diagnosis and treatment are essential to achieve favorable outcome in such cases because venous congestion results in irreversible venous infarction within a short period.

Multiple spontaneous coronary artery ruptures and cardiac tamponade in vascular Ehlers-Danlos syndrome.

We report a case of a 45-year-old woman with Ehlers-Danlos syndrome (EDS) type IV, the vascular type, who presented with multiple coronary artery ruptures causing cardiac tamponade. She had sudden onset of chest pain soon after transarterial embolization for right carotid-cavernous fistula. Transthoracic echocardiography confirmed cardiac tamponade and hypokinetic inferolateral wall. Enhanced CT and transesophageal echocardiography ruled out aortic dissection. Coronary angiography showed contrast extravasation from multiple sites of the right coronary artery and left circumflex coronary artery. We suspected EDS type IV, and a skin biopsy for DNA and RNA analysis was done after taking written informed consent. Polymerase chain reaction (PCR) and sequencing of the PCR product showed a heterozygous missense mutation of codon 85 in the COL3A1 gene, which converted glycine to aspartic acid, and thus a diagnosis of EDS type IV was established. To our best knowledge, this is the first case of EDS type IV causing multiple coronary artery ruptures.

Clinical and angiographic characteristics of cavernous sinus dural arteriovenous fistulas manifesting as venous infarction and/or intracranial hemorrhage.

INTRODUCTION: Cavernous sinus (CS) dural arteriovenous fistulas (DAVFs) rarely cause venous infarction (VI) and/or intracranial hemorrhage (ICH) despite the presence of cortical venous drainage (CVD). The present study investigated the characteristics of CS DAVFs manifesting as VI/ICH. MATERIALS AND METHODS: Fifty-four patients treated for CS DAVFs were retrospectively studied. RESULTS: Six patients presented with VI/ICH. Two of the three patients presenting with ICH had CVD only to the superficial sylvian vein (SSV) or the deep sylvian vein (DSV). Three patients presenting with VI had multiple drainages, and angiography of these patients showed a varix on the SSV, drainage into the DSV with agenesis of the second and third segment of basal vein of Rosenthal, and thrombosis of the distal petrosal vein. CS DAVF with CVD only carries higher risk of VI/ICH than multiple drainages. Many CS DAVFs presenting with VI, especially those with drainage into the petrosal vein, have multiple drainages in the early stage. Thrombosis of the inferior and superior petrosal sinuses and superior orbital vein gradually increases pressure of the CVD, and then, VI may occur. In contrast, CS DAVFs with CVD only from the beginning, common in the patients with drainage into the SSVs and DSVs, are likely to cause ICH. CONCLUSION: Angiographic risk factors causing VI/ICH are CVD only, varix formation, agenesis of the second and third segment of basal vein of Rosenthal, and thrombosis of the superior orbital vein, lateral half of the superior petrosal sinus, and distal CVD.

Urgent stenting for patients with acute stroke due to atherosclerotic occlusive lesions of the cervical internal carotid artery.

Acute symptomatic occlusion of the cervical internal carotid artery (ICA) can be treated by intravenous administration of tissue plasminogen activator, percutaneous transluminal angioplasty, and carotid endarterectomy. Carotid artery stenting (CAS) is now indicated for cervical ICA stenosis, but the safety and the efficacy of urgent CAS have not been established. We retrospectively reviewed 10 patients treated by urgent CAS for atherosclerotic occlusive lesions of cervical ICA with acute stroke. Five patients had complete occlusions and five had near total occlusions. Five of the 10 patients had intracranial tandem occlusions. Indication for urgent CAS was determined by mismatch of diffusion-weighted and perfusion-weighted magnetic resonance imaging findings. Stents were successfully deployed in all lesions. Three of five patients with concomitant intracranial tandem occlusions were treated by additional intraarterial fibrinolysis after the CAS. Intracranial artery occlusions were completely recanalized in one patient, and partially recanalized in two by fibrinolysis. Hyperperfusion syndrome did not occur in any of the patients. A favorable outcome (modified Rankin Scale < or =1) was obtained in all of the five patients with isolated cervical ICA occlusion and one of the five patients with intracranial tandem occlusions. Urgent CAS is a safe and effective treatment in patients with isolated cervical ICA occlusion. Treatment of intracranial tandem occlusions is an issue that must be resolved.

Management of intracranial vertebral artery dissections initially presenting without subarachnoid hemorrhage.

OBJECTIVE: The clinical and angiographic follow-up results for intracranial vertebral artery (VA) dissections that initially presented without subarachnoid hemorrhage (SAH) were retrospectively investigated, to clarify their management. METHODS: Twenty-one patients with VA dissections that initially presented without SAH were studied. Initial angiography revealed aneurysmal dilation in 11 cases (typical pearl-and-string sign in 8 cases, aneurysmal dilation only in 2, and aneurysmal dilation with double-lumen sign in 1), occlusion in 7, double-lumen sign in 2, and string-like stenosis in 1. Nine patients (six with pearl-and-string sign, one with occlusion with aneurysmal dilations, and two with double-lumen sign), including three patients who experienced subsequent SAH, underwent endovascular proximal parent artery occlusion. The other 12 patients were treated conservatively. All patients were monitored with magnetic resonance angiography or digital subtraction angiography. RESULTS: Three patients experienced subsequent SAH, 1 day (two patients) or 51 months after onset. Follow-up angiographic assessments of the 20 patients demonstrated complete resolution in five cases, reduction of aneurysmal dilation in one case, and partial recanalization in one case. However, enlargement or formation of an aneurysmal dilation was recognized in four cases and progression of dissection was observed in one case. Eighteen patients experienced good recoveries, and three patients demonstrated moderate disabilities as a result of the initial ischemic insult. CONCLUSION: The risk of bleeding from unruptured VA dissections is higher than previously considered. Therefore, endovascular treatment should be considered for patients with VA dissections with relatively large or growing aneurysmal dilations.