Aortogenic calcified cerebral embolism diagnosed with an embolus retrieved by thrombectomy: illustrative case.

BACKGROUND: Calcified cerebral embolism has been reported as a cause of acute cerebral infarction, but an aortogenic origin has rarely been identified as the embolic source. The authors describe a case of aortogenic calcified cerebral embolism in a patient with other embolic sources. OBSERVATIONS: In a patient with cerebral infarction and atrial fibrillation, a white hard embolus was retrieved by mechanical thrombectomy. Pathological analysis of the embolus revealed that it was mostly calcified, with some foam cells and giant cells. The macroscopic and pathological findings allowed the authors to finally diagnose an aortogenic calcified cerebral embolism. LESSONS: Even in patients with cardiogenic embolic sources, it is possible to identify a complex aortic atheroma with calcification as the embolic source, based on the macroscopic and pathological findings of the embolus retrieved by mechanical thrombectomy.

Factors related to vessel displacement due to stent retriever retraction: An in vitro study.

BACKGROUND: Thrombectomy with a stent retriever (SR) may lead to intracranial hemorrhage due to vessel displacement. We aimed to explore factors related to vessel displacement using an in vitro vessel model. METHODS: A vessel model mimicking two-dimensional left internal carotid angiography findings was used in this study. Six SR types (Solitaire 3 × 40, 4 × 40, and 6 × 40; Embotrap 5 × 37; Trevo 4 × 41; and Tron 4 × 40) were fully deployed in the M2 ascending, M2 bend, or M1 horizontal portion. Subsequently, the SR was retracted, and the vessel displacement, maximum SR retraction force, and angle of the M2 bend portion were measured. A total of 180 SR retraction experiments were conducted using 6 SR types at 3 deployment positions with 10 repetitions each. RESULTS: The mean maximum distance of vessel displacement for Embotrap Ⅲ 5 × 37 (6.4 ± 3.5 mm, n = 30) was significantly longer than that for the other five SR types (p = 0.029 for Solitaire 6 × 40 and p < 0.001 for the others, respectively). Vessel displacement was significantly longer in the M2 ascending portion group (5.4 ± 3.0 mm, n = 60) than in the M2 bend portion group (3.3 ± 1.6 mm, n = 60) (p < 0.001) and it was significantly longer in the M2 bend portion group than in the M1 horizontal portion group (1.1 ± 0.7 mm, n = 60) (p < 0.001). A positive correlation existed between the mean maximum SR retraction force or mean angle of the M2 bend portion due to SR retraction (i.e., vessel straightening) and the mean maximum distance of vessel displacement (r = 0.90, p < 0.001; r = 0.90, p < 0.001, respectively). CONCLUSIONS: Vessel displacement varied with the SR type, size, and deployment position. Moreover, vessel displacement correlated with the SR retraction force or vessel straightening of the M2 bend portion.

Basilar artery occlusion due to vertebral artery injury treated with thrombectomy and distal vertebral artery embolization through the unaffected side.

Background: There is no established opinion regarding embolization of asymptomatic traumatic vertebral artery injuries that do not require cervical spine repair and fixation. Case Description: A 78-year-old man fell backward from a height of about 1 m and was rushed to his previous hospital. He had a fracture of the left transverse process of the 6th cervical vertebra. Six hours after the trauma, he became unconscious; magnetic resonance angiography showed occlusion of the left vertebral and basilar arteries, and he was transferred to our hospital. The basilar artery was completely recanalized 430 min after the onset of unconsciousness. Due to the presence of thrombi in the distal vertebral artery at the level of the 6th cervical vertebra and collateral blood flow from the deep cervical artery, the distal vertebral artery was occluded to prevent embolism. Postoperative diffusion-weighted imaging showed extensive infarction in the posterior circulation, and the patient died two days after surgery. Conclusion: In the case of vertebral artery injury, preparation for early occlusion of the basilar artery is necessary. If a thrombus and collateral blood flow are present distal to the vertebral artery injury, distal vertebral artery embolization may be necessary to prevent embolism.

Superiority of Endovascular Coiling Over Surgical Clipping for Clinical Outcomes at Discharge in Patients With Poor-Grade Subarachnoid Hemorrhage: A Registry Study in Japan.

BACKGROUND AND OBJECTIVES: The differences in clinical outcomes between endovascular coiling (EC) and surgical clipping (SC) in patients with poor-grade aneurysmal subarachnoid hemorrhage (aSAH) are controversial. Therefore, this study aimed to evaluate whether EC is superior to SC and identify risk factors in patients with poor-grade aSAH. METHODS: We used data from the "Predict for Outcome Study of aneurysmal SubArachnoid Hemorrhage." World Federation of Neurological Societies (WFNS) grade III-V aSAH was defined as poor-grade aSAH, and unfavorable clinical outcomes (modified Rankin Scale scores 3-6) were compared between SC and EC after propensity score matching (PSM). In-hospital mortality was similarly evaluated. Predictors of unfavorable clinical outcomes were identified using multivariable analysis. RESULTS: Ultimately, 1326 (SC: 847, EC: 479) and 632 (SC: 316, EC: 316) patients with poor-grade aSAH were included before and after PSM, respectively. Unfavorable clinical outcomes at discharge were significantly different between SC and EC before (72.0% vs 66.2%, P = .026) and after PSM (70.6% vs 63.3%, P = .025). In-hospital mortality was significantly different between groups before PSM (10.5% vs 16.1%, P = .003) but not after PSM (10.4% vs 12.7%, P = .384). Predictors of unfavorable clinical outcomes in both SC and EC were WFNS grade V, older than 70 years, and Fisher computed tomography (CT) grade 4. Predictors of unfavorable clinical outcomes only in SC were WFNS grade IV (odds ratio: 2.46, 95% CI: 1.22-4.97, P = .012) and Fisher CT grade 3 (4.90, 1.42-16.9, P = .012). Predictors of unfavorable clinical outcome only in EC were ages of 50s (3.35, 1.37-8.20, P = .008) and 60s (3.28, 1.43-7.52, P = .005). CONCLUSION: EC resulted in significantly more favorable clinical outcomes than SC in patients with poor-grade aSAH, without clear differences in in-hospital mortality. The benefit of EC over SC might be particularly remarkable in patients with WFNS grade IV and Fisher CT grade 3.

Anterior condylar arteriovenous fistula mainly fed by peripheral branches of the bilateral internal maxillary arteries: illustrative case.

BACKGROUND: The main feeding artery of an anterior condylar arteriovenous fistula (AC-AVF) is the ascending pharyngeal artery and rarely the internal maxillary artery. OBSERVATIONS: A 58-year-old male with a history of sinusitis since adolescence presented with a 5-year history of bilateral pulsatile tinnitus and a 2-month history of right ocular symptoms. Angiography showed that the peripheral branches of the bilateral internal maxillary arteries were the main feeding arteries of the AC-AVF and that they gathered in the clivus with a relatively large shunted pouch in the left jugular tubercle. Shunt flow drained to the right external jugular vein via the right superior ophthalmic vein. A sheath was placed in the right external jugular vein, and a small distal access catheter was guided to the right superior ophthalmic vein to allow the microcatheter to reach the shunted pouch. Selective angiography of the contralateral sphenopalatine artery allowed us to confirm the gathering site of the feeding arteries and the shunted pouch and archive the complete occlusion. LESSONS: Selective angiography of the contralateral sphenopalatine artery may be useful to confirm the gathering site of the peripheral branches of the bilateral internal maxillary arteries in an AC-AVF.

Parent artery occlusion for cerebral infarction after spontaneous recanalization in traumatic vertebral artery: A case report.

Background: There is no established treatment strategy for traumatic vertebral artery occlusion that does not require cervical spine repair surgery. Case Description: A 49-year-old man was brought to our hospital with traffic trauma. Fractures were observed in the left lateral mass and transverse process of Atlas and the left vertebral artery was occluded at the level of the foramen transversum of Atlas. No acute cerebral infarction was observed. Because the cervical spinal cord was not compressed by the fracture, no repair surgery was performed. Continuous intravenous heparin and oral aspirin were started for traumatic vertebral artery occlusion. Thereafter, the left vertebral artery spontaneously recanalized, but no cerebral infarction was observed. The patient was discharged home on day 16 of injury. Four days later, however, he was brought to our hospital with nausea and lightheadedness. Acute cerebral infarction was observed in the left posterior inferior cerebellar artery territory and a thrombus in the left vertebral artery V4 segment. Parent artery occlusion was performed to prevent further cerebral infarction due to distal embolization of the thrombus. No further cerebral infarction occurred after the operation and the patient was discharged home with a modified Rankin scale score of 1. Conclusion: In cases of traumatic vertebral artery occlusion without an occlusive mechanism, parent artery occlusion may be considered in terms of recanalization risk, regardless of the need for repair surgery.

Disconnection of a stent retriever's pushwire caught by an accordion-like deformed aspiration catheter during mechanical thrombectomy: illustrative case.

BACKGROUND: In mechanical thrombectomy for acute large vessel occlusion, a combined technique of using both a stent retriever and an aspiration catheter has been widely used. The authors report a case in which a stent retriever's pushwire and a microcatheter were caught and disconnected by an accordion-like deformed aspiration catheter. OBSERVATIONS: A 74-year-old man underwent mechanical thrombectomy for a left M1 occlusion. A stent retriever was deployed from the left M2 to the left distal M1, and an aspiration catheter was advanced to the left distal M1. When the stent retriever and microcatheter were pulled into the aspiration catheter at the distal M1 without releasing the deflection, traction resistance of the stent retriever occurred, and the aspiration catheter contracted and deformed like an accordion distal to the tip of the guiding catheter. The stent retriever's pushwire and the microcatheter were caught and disconnected. LESSONS: When a stent retriever is pulled into a flexible aspiration catheter in a case with vascular tortuosity, it may be caught by an accordion-like deformed aspiration catheter and disconnected. It is necessary to release the deflection of the aspiration catheter once traction resistance of the stent retriever and deflection of the aspiration catheter occur.

De novo expansion formation in the outer curvature of the internal carotid artery after flow diverter deployment for an infectious cavernous carotid aneurysm: illustrative case.

BACKGROUND: Infectious aneurysms very rarely occur in the cavernous carotid artery. Recently, treatment by flow diverter implantation with preservation of the parent artery has been the treatment of choice. OBSERVATIONS: A 64-year-old woman presented with stenosis at the C5 segment of the left internal carotid artery (ICA), followed by ocular symptoms within 2 weeks, with a de novo aneurysm in the left cavernous carotid artery and wall irregularity with stenosis from the C2 to C5 segments of the left ICA. Antimicrobial therapy was given for 6 weeks, and a Pipeline Flex Shield was implanted. Angiography 6 months after treatment showed complete obliteration of the infectious aneurysm and improvement of the stenosis. However, de novo expansions were formed in the outer curvature of C3 and C4 segments of the ICA where the Pipeline device had been deployed. LESSONS: Aneurysms that develop rapidly and show shape changes over time, accompanied by fever and inflammation, may be associated with an infection. Because of the fragility in the irregular wall of the parent vessel associated with infectious aneurysms, de novo expansion may form in the outer curvature of the parent vessel after flow diverter placement; thus, careful follow-up is necessary.

Cavernous sinus dural arteriovenous fistula embolized through an occluded superior petrosal sinus: illustrative case.

BACKGROUND: Transvenous embolization for cavernous sinus (CS) dural arteriovenous fistulas (CS-DAVFs) with limitations of the major access routes to the CS is challenging. OBSERVATIONS: A 74-year-old woman presented with left-sided conjunctival injection and exophthalmos. Cerebral angiography showed a left CS-DAVF draining into the left uncal vein and superior ophthalmic vein, with the fistulous point located in the posterosuperior compartment of the left CS. The left inferior petrosal sinus and internal jugular vein were occluded, and no drainage route from the left superior ophthalmic vein was seen. The anterior segment of the left superior petrosal sinus (SPS) was occluded, but the posterior segment was not. Microangiography from the posterior segment of the left SPS showed a beak-like orifice in the anterior segment of the left SPS toward the left CS. A micro-guidewire was guided through the beak-like orifice, and the microcatheter was advanced into the left CS. The left CS was packed and the DAVF was occluded. LESSONS: Transvenous embolization through an occluded SPS may be an option in the endovascular treatment of CS-DAVFs. Penetration along the beak-like orifice of the occluded SPS visualized by venography at the blind end of the SPS may be useful in reaching the CS via the SPS.

Factors for failure of ultrasound-guided compression repair for femoral pseudoaneurysms after neuroendovascular therapy.

OBJECTIVE: Pseudoaneurysms are a serious complication of neuroendovascular therapy with femoral artery puncture, for which ultrasound-guided compression repair (UGCR) is often the first choice of radical therapy. We sought to retrospectively investigate the factors for failure of UGCR for pseudoaneurysm at the femoral artery puncture site. METHODS: Among patients undergoing neuroendovascular therapy with femoral artery puncture at our hospital between January 2018 and April 2021, those who received a diagnosis of pseudoaneurysm and underwent UGCR were enrolled. They were classified into two groups according to whether UGCR was successful (UGCR group) or was converted to surgical repair (SR group). Patient and procedural characteristics were compared between the two groups. RESULTS: During the study period, 577 patients underwent neuroendovascular therapy with femoral artery puncture, 10 of whom (1.7%) received a diagnosis of pseudoaneurysm and underwent UGCR. There were seven patients in the UGCR group and three patients in the SR group. The sheath diameter tended to be larger in the SR group than in the UGCR group (p = 0.16). The modified Rankin scale score when a diagnosis of pseudoaneurysm was made was significantly lower in the SR group than in the UGCR group (1 [0-2] vs. 3 [2-5], p = 0.037). CONCLUSIONS: Physical activity may be associated with failure of UGCR. In patients with high physical activity, the use of sedatives and analgesics to keep them at rest during puncture site compression after UGCR may lead to successful UGCR.

Dilation of proximal internal carotid artery collapse due to severe distal stenosis after angioplasty for distal stenosis: A case report.

Background: We report a case of proximal internal carotid artery (ICA) collapse due to severe distal stenosis that dilated after angioplasty for distal stenosis. Case Description: A 69-year-old woman underwent thrombectomy for the left ICA occlusion due to stenosis of C3 portion and was discharged home with a modified Rankin Scale score of 0. One year later, she developed cerebral infarction due to progressive stenosis of the C3 portion of the left ICA with proximal ICA collapse and underwent emergency percutaneous transluminal angioplasty (PTA) for distal stenosis. Device guidance to the stenosis was difficult due to proximal ICA collapse. After PTA, blood flow in the left ICA increased, and proximal ICA collapse dilated over time. Due to severe residual stenosis, she underwent more aggressive PTA followed by Wingspan stenting. Device guidance to the residual stenosis was facilitated because proximal ICA collapse had already dilated. Six months later, proximal ICA collapse further dilated. Conclusion: PTA for severe distal stenosis with proximal ICA collapse may result in dilation of proximal ICA collapse over time.

White Embolus-induced Basilar Artery Occlusion Due to Pulmonary Vein Invasion of a Metastasis of a Malignant Melanoma.

An 80-year-old woman presented with impaired consciousness after malignant melanoma resection. Magnetic resonance angiography showed basilar artery occlusion, which was subjected to mechanical thrombectomy for recanalization. A pathological analysis of the retrieved embolus revealed that it was derived from a metastasis of malignant melanoma. Contrast-enhanced chest computed tomography showed multiple pulmonary metastases, one of which was in the right upper lobe and invaded the pulmonary vein. To our knowledge, this is the first case of white embolus-induced cerebral embolism due to pulmonary vein invasion of a metastasis of a pathologically diagnosed malignant melanoma.

Factors related to white thrombi in acute ischemic stroke in cancer patients.

OBJECTIVES: Thrombi in cerebral large vessel occlusion associated with active cancer are often fibrin and platelet-rich white thrombi. However, evaluating the thrombus composition in a short time before thrombectomy is often ineffective. We sought to determine factors related to white thrombi in acute ischemic stroke due to large vessel occlusion in cancer patients. METHODS: Consecutive cancer patients undergoing thrombectomy for acute ischemic stroke due to large vessel occlusion between January 2018 and May 2022 were retrospectively reviewed. The patients were classified into white thrombus and red thrombus groups on the basis of the pathological findings of retrieved thrombi. Patient characteristics and laboratory findings were compared between the two groups. RESULTS: There were 12 patients in the white thrombus group and 11 patients in the red thrombus group. Active cancer was significantly more in the white thrombus group than in the red thrombus group (91.7% vs. 36.3%, p = 0.0094). Internal carotid artery occlusion was significantly less in the white thrombus group than in the red thrombus group (0% vs. 36.4%, p = 0.037). Among laboratory findings, D-dimer levels were an independent factor associated with white thrombi (odds ratio 8.97 [95% confidence interval 1.71-368.99], p < 0.0001). The cutoff value of D-dimer levels for predicting white thrombi was 3.5 µg/mL (83.3% sensitivity and 100% specificity). CONCLUSIONS: In acute ischemic stroke in cancer patients, active cancer, no internal carotid artery occlusion, and higher D-dimer levels (≥3.5 µg/mL) may be associated with occlusion with fibrin and platelet-rich white thrombi.

Analysis of Factors Influencing Delayed Presentation in Japanese Patients with Subarachnoid Hemorrhage.

OBJECTIVE: Some aneurysmal subarachnoid hemorrhage (SAH) patients are delayed in their presentation. This can cause a washout of the subarachnoid hematoma and a potential misdiagnosis. As a result, they may suffer rerupture of the aneurysm and preventable deterioration. We investigated the factors that influence delayed SAH presentation. METHODS: Aneurysmal SAH patients treated at 9 stroke centers from 2002 to 2020 were included. Age, gender, pre-SAH modified Rankin scale, World Federation of Neurological Surgeons grade, Fisher group, day of presentation, aneurysm treatment method, past history of cerebral stroke, comorbidity of hypertension and/or diabetes mellitus, and modified Rankin scaleat discharge were assessed retrospectively. We formed 2 groups based on the day of presentation after the onset of SAH: day 0-3 (early) and other (delayed). Logistic regression analyses detected the factors that influenced the day of presentation and outcome for SAH. A P- value <0.05 was considered significant. RESULTS: Delayed presentation comprised 282 cases (6.3%) of 4507 included cases. Logistic regression analyses showed that patients in an urban area, of male gender, low WFNS grade and low Fisher group correlated significantly with a delayed presentation. But delayed presentation did not influence outcome at discharge. CONCLUSIONS: Area of residency and gender correlated with delayed presentation after SAH in Japan. Urbanization, male gender, and mild SAH lead patients to delay presentation. The factors underlying these tendencies will be analyzed in a future prospective study.

Intraoperative identification of the lateral spinal artery in a case of craniocervical junction dural arteriovenous fistula surgically obliterated.

BACKGROUND: The formation of a dural arteriovenous fistula (DAVF) at the craniocervical junction is rare. Such a fistula can be fed by the branches of the vertebral and external carotid arteries. The lateral spinal artery can branch from the vertebral artery. The feeders of a DAVF at the craniocervical junction are often diagnosed on preoperative angiography, and there is little reported evidence on the intraoperative diagnosis of the lateral spinal artery. CASE DESCRIPTION: An 84-year-old man presented with motor weakness and sensory disturbance of the lower extremities. Edematous changes in the medulla oblongata and cervical spinal cord were observed on magnetic resonance imaging. Cerebral angiography revealed a DAVF fed by a branch of the vertebral artery, with a shunting point located in the dura of the right condyle; the main drain was the anterior spinal vein. The DAVF drain was surgically obliterated to prevent hemorrhagic events and improve neurological symptoms. Intraoperatively, an artery branching from the feeder of the DAVF was identified and preserved. The patient had a good postoperative course, and the neurological symptoms were ameliorated. Follow-up cerebral angiography revealed proximal branching of the lateral spinal artery from the feeding artery of the DAVF. CONCLUSION: A lateral spinal artery was identified intraoperatively while a DAVF at the craniocervical junction was obliterated. This suggests that preoperative imaging should be carefully reviewed, and endovascular procedures should consider such possibilities to avoid adverse ischemic outcomes.

Microcatheter movement in the aneurysm due to low-profile visualized intraluminal support deployment: An in vitro study.

BACKGROUND: When a microcatheter is in the aneurysm, it may move due to low-profile visualized intraluminal support (LVIS) deployment. This study was designed to determine this mechanism. METHODS: Six silicon aneurysm models were created by combining the aneurysm location (side wall or bifurcation) and the parent vessel configuration (straight, ipsilateral bending, or contralateral bending). After adjusting the microcatheter tip position in the aneurysm by pushing or pulling, an LVIS stent was deployed to cover the aneurysm neck, and the changes in the microcatheter tip position was measured. Pushing and pulling were performed 15 times each for each model, for a total of 180 experiments. RESULTS: In all experiments, the microcatheter tip moved with LVIS deployment. The total movement distance was 3.00±1.59 mm, which was significantly different between the push and pull groups (p = 0.049), between the three side-wall aneurysm models (p<0.0001), and between the three bifurcation aneurysm models (p<0.0001). Backward movement in the aneurysm occurred in 21% (37/180). The frequency of backward movement was significantly different between the side-wall and bifurcation aneurysm models (p = 0.0265) and between the push and pull groups (p<0.0001). The forward movement distance was significantly different between the side-wall (n = 78) and bifurcation (n = 65) aneurysm models (p<0.0001). CONCLUSIONS: The aneurysm location, the parent vessel configuration, and adjustment of the microcatheter tip position by pushing or pulling may affect the total movement distance and forward/backward movement of the microcatheter tip due to LVIS deployment.

Predicting the growth of middle cerebral artery bifurcation aneurysms using differences in the bifurcation angle and inflow coefficient.

OBJECTIVE: Growing intracranial aneurysms (IAs) are prone to rupture. Previous cross-sectional studies using postrupture morphology have shown the morphological or hemodynamic features related to IA rupture. Yet, which morphological or hemodynamic differences of the prerupture status can predict the growth and rupture of smaller IAs remains unknown. The purpose of this longitudinal study was to investigate the effects of morphological features and the hemodynamic environment on the growth of IAs at middle cerebral artery (MCA) bifurcations during the follow-up period. METHODS: One hundred two patients with MCA M1-2 bifurcation saccular IAs who underwent follow-up for more than 2 years at the authors' institutions between 2011 and 2019 were retrospectively identified. During the follow-up period, cases involving growth of MCA IAs were assigned to the event group, and those with MCA IAs unchanged in size were assigned to the control group. The morphological parameters examined were aneurysmal neck length, dome height, aspect ratio and volume, M1 and M2 diameters and their ratio, and angle configurations among M1, M2, and the aneurysm. Hemodynamic parameters were flow rate and wall shear stress in M1, M2, and the aneurysm, including the aneurysmal inflow rate coefficient (AIRC), defined as the ratio of the aneurysmal inflow rate to the M1 flow rate. Those parameters were compared statistically between the two groups. Correlations between morphological and hemodynamic parameters were also examined. RESULTS: Eighty-three of 102 patients were included: 25 with growing MCA IAs (event group) and 58 with stable MCA IAs (control group). The median patient age at initial diagnosis was 66.9 (IQR 59.8-72.3) years. The median follow-up period was 48.5 (IQR 36.5-65.6) months. Both patient age and the AIRC were significant independent predictors of the growth of MCA IAs. Moreover, the AIRC was strongly correlated with sharper bifurcation and inflow angles, as well as wider inclination angles between the M1 and M2 arteries. CONCLUSIONS: The AIRC was a significant independent predictor of the growth of MCA IAs. Sharper bifurcation and inflow angles and wider inclination angles between the M1 and M2 arteries were correlated with the AIRC. MCA IAs with such a bifurcation configuration are more prone to grow and rupture.

Short-term aneurysm formation and rupture due to septic embolism diagnosed with a thrombus retrieved from another occluded artery.

Background: In rare cases, septic embolism is diagnosed on the basis of pathological findings of retrieved thrombi. Infected aneurysms can rapidly form and rupture after septic embolism, leading to a poor prognosis. We report a case of subcortical hemorrhage due to an infected aneurysm forming shortly after septic embolism in the left anterior cerebral artery. Case Description: In this case, the diagnosis of septic embolism was made on the basis of pathological findings of a thrombus retrieved from the simultaneously occluded left middle cerebral artery, and endovascular embolization of the infected aneurysm was performed. Conclusion: The pathological findings of a retrieved thrombus were useful for making a diagnosis of septic embolism. The possibility of short-term formation and rupture of an infected aneurysm after septic embolism should be noted. Endovascular embolization of occluded vessels due to septic embolism may prevent aneurysm formation and subsequent bleeding.

Clinical features and long-term outcomes of symptomatic low-grade carotid stenosis.

OBJECTIVE: In symptomatic low-grade stenosis, most of the reports did not clarify the long-term outcome. This study aims to clarify the clinical features and long-term outcomes of symptomatic low-grade stenosis cases. MATERIALS AND METHODS: We included 123 symptomatic patients with low-grade (<50%) carotid stenosis. The relative plaque signal intensity (rSI) and expansive remodeling rate (ERR) were measured using carotid magnetic resonance imaging (MRI). Antiplatelet therapy and treatment for atherosclerosis risk factors were administered in all cases. Carotid endarterectomy (CEA) was performed when ischemic symptoms appeared, or the percent stenosis progressed despite medical treatment. RESULTS: The mean percent stenosis, rSI, and ERR on admission were 22.3, 1.70, and 2.01, respectively. The mean volume of the hyperintense plaque on carotid MRI was 641.4± 540 mm3. Sixty percent of cases involved intraplaque hemorrhage and expansive remodeling. During a mean follow-up of 52 months, recurrence of ischemic events was confirmed in 45 cases (36.6%). Of the 67 cases performed follow-up MRI, 34 cases (50%) had an increased volume of T1-hyperintense plaque. CEA or carotid artery stenting was performed in 49 cases. During a mean follow-up of 57.8 months after CEA, two cases of death (fatal intracerebral hemorrhage and asphyxia) and one case of brain stem lacunar infarction were observed, but ipsilateral ischemic events were not. CONCLUSION: Most of the symptomatic patients with low-grade stenosis had both intraplaque hemorrhage and expansive remodeling and presented a high risk of recurrence and stenosis progression. CEA may have preventive effects against ischemic events in low-grade stenosis.

Aneurysm Perforation Due to Advancement of the Coil Delivery Wire During Stent-Assisted Embolization.

We report a case of intraprocedural aneurysm rupture during coil embolization caused by a coil delivery wire. A 68-year-old woman underwent stent-assisted coil embolization for an unruptured aneurysm in the internal carotid artery (ICA). A low profile visible intraluminal support device was deployed at the aneurysm neck. Coil embolization was performed with a jailing technique. After deflection of the jailed microcatheter was released, a coil was placed in the aneurysm against resistance to coil insertion. The movement of the microcatheter tip was restricted with the stent. A coil delivery wire that was advanced after coil detachment perforated the aneurysm. Hemostasis was achieved, and coil embolization was finished with a slight neck remnant. Complete occlusion of the aneurysm was confirmed on angiography six months later. Advancement of a coil alignment marker after coil detachment may cause aneurysm perforation due to coil delivery wire advancement. In stent-assisted coil embolization, when the movement of the microcatheter tip in the aneurysm is restricted by the stent and there is resistance to coil insertion, the risk of perforation due to the coil delivery wire after coil detachment should be noted.