Percutaneous transluminal angioplasty and stenting for severe stenosis of the intracranial carotid artery and its branches: Comparison of the Wingspan stent versus the Credo stent.

BACKGROUND: Despite the widespread use of the Wingspan stent system for treating severe medically refractory intracranial artery stenosis (SMR-ICAS), a new Credo stent system was approved because it could integrate stent delivery within the balloon catheter. However, the therapeutic outcomes of these two systems have not been compared. This preliminary study aimed to compare the results of percutaneous angioplasty and stenting (PTAS) in SMR-ICAS patients treated with either Wingspan or Credo stents within the anterior circulation. METHODS: SMR-ICAS patients with more than 70% stenosis in the anterior circulation who underwent PTAS using either the Wingspan or Credo stent system were analyzed. We evaluated the technical success, safety, and outcomes of the two stent systems. RESULTS: A total of 29 patients were analyzed, including 17 patients treated with Wingspan stents and 12 with Credo stents. The outcomes of the Wingspan stent vs. Credo stent were as follows: technical success (16/17 [94%] vs. 11/12 [92%], p = 1.00); periprocedural intracranial hemorrhage (2/17 [12%] vs. 0/12 [0%], p = 0.50); silent embolic ischemic lesions on peri-procedural MRI (13/17 [76%] vs. 7/12 [58%], p = 0.42); and significant (more than 50%) in-stent restenosis in one year (4/17 [24%] vs. 2/12 [17%], p = 1.00). No recurrent stroke or mortality was noted within 30 days after the procedures or during the one-year follow-up period. CONCLUSION: The technical success, safety, and outcomes of the Credo stent system were comparable to those of the Wingspan stent system in the management of SMR-ICAS patients. Further large-scale studies are warranted to substantiate these findings.

Shortened Cerebral Circulation Time Predicts Resistance to Obliteration in High-Flow Brain Arteriovenous Malformations After Stereotactic Radiosurgery.

BACKGROUND AND OBJECTIVES: Treatment selection for brain arteriovenous malformations (BAVMs) is complicated by BAVM size, location, and hemodynamics. Quantitative digital subtraction angiography is used to quantify the hemodynamic impact of BAVMs on cerebral circulation. This study investigated the association between cerebral circulation time and the complete obliteration (CO) rate of BAVMs after stereotactic radiosurgery (SRS). METHODS: We analyzed the data of 143 patients who underwent SRS for BAVMs between January 2011 and December 2019 in our institute. Their pre-SRS magnetic resonance imaging and angiography images were analyzed to acquire BAVM characteristics and quantitative digital subtraction angiography parameters. Modified cerebral circulation time (mCCT) was defined as the time difference between the bolus arrival time of the ipsilateral cavernous internal carotid artery and that of the parietal vein, as determined from the lateral view of images obtained using digital subtraction angiography. Cox regression with hazard ratios and Kaplan-Meier analyses were conducted to determine the associations between the parameters and BAVM CO after SRS. RESULTS: Of the 143 patients, 101 (70.6%) achieved BAVM CO. According to the multivariate analyses, an increased mCCT (hazard ratio: 1.24, P = .041) was the independent factor associated with BAVM CO after adjustment for age, sex, hemorrhagic presentation, a BAVM volume of >5 cm3, and a margin dose of >18 Gy. Individuals with an mCCT of ≤2.32 s had a lower 36-month probability of BAVM CO than did those with an mCCT of >2.32 s (44.1% ± 6.8% vs 63.3% ± 5.6%, P = .034). CONCLUSION: The hemodynamic impact of high-flow BAVM demonstrated by a shortened mCCT is associated with a lower BAVM CO rate after SRS.

Endovascular Management of Post-Irradiated Carotid Blowout Syndrome in Patients with Lower Neck Cancers.

OBJECTIVE: Lower neck cancers (LNCs) include specific tumour types and have some different vascular supply or collaterals from other head and neck cancers. This prospective study evaluated the outcome of endovascular management of post-irradiated carotid blowout syndrome (PCBS) in patients with LNC by comparing reconstructive management (RE) and deconstructive management (DE). METHODS: This was a single centre, prospective cohort study. Patients with LNC complicated by PCBS between 2015 and 2021 were enrolled for RE or DE. RE was performed by stent graft placement covering the pathological lesion and preventive external carotid artery (ECA) embolisation without balloon test occlusion (BTO). DE was performed after successful BTO by permanent coil or adhesive agent embolisation of the internal carotid artery (ICA) and ECA to common carotid artery, or ICA occlusion alone if the pathological lesion was ICA only. Cross occlusion included the proximal and distal ends of the pathological lesion in all patients. Re-bleeding events, haemostatic period, and neurological complications were evaluated. RESULTS: Fifty-nine patients (mean age 58.5 years; 56 male) were enrolled, including 28 patients undergoing RE and 31 patients undergoing DE. Three patients originally grouped to DE were transferred to RE owing to failed BTO. The results of RE vs. DE were as follows: rebleeding events, 13/28 (46%) vs. 10/31 (32%) (p = .27); haemostatic period, 9.4 ± 14.0 months vs. 14.2 ± 27.8 months (p = .59); neurological complication, 4/28 (14%) vs. 5/31 (16%) (p = .84); and survival time, 11.8 ± 14.6 months vs. 15.1 ± 27.5 months (p = .61). CONCLUSION: No difference in rebleeding risk or neurological complications was observed between the DE and RE groups. RE could be used as a potential routine treatment for PCBS in patients with LNC.

Percutaneous transluminal angioplasty and stenting of post-irradiated stenosis of subclavian artery: A matched case-control study.

BACKGROUND: Although radiotherapy is common for head/neck and chest cancers (HNCC), it can result in post-irradiation stenosis of the subclavian artery (PISSA). The efficacy of percutaneous transluminal angioplasty and stenting (PTAS) to treat severe PISSA is not well-clarified. AIMS: To compare the technical safety and outcomes of PTAS between patients with severe PISSA (RT group) and radiation-naïve counterparts (non-RT group). METHODS: During 2000 and 2021, we retrospectively enrolled patients with severe symptomatic stenosis (>60%) of the subclavian artery who underwent PTAS. The rate of new recent vertebrobasilar ischaemic lesions (NRVBIL), diagnosed on diffusion-weight imaging (DWI) within 24 h of postprocedural brain MRI; symptom relief; and long-term stent patency were compared between the two groups. RESULTS: Technical success was achieved in all 61 patients in the two groups. Compared with the non-RT group (44 cases, 44 lesions), the RT group (17 cases, 18 lesions) had longer stenoses (22.1 vs 11.1 mm, P = 0.003), more ulcerative plaques (38.9% vs 9.1%, P = 0.010), and more medial- or distal-segment stenoses (44.4% vs 9.1%, P<0.001). The technical safety and outcome between the non-RT group and the RT group were NRVBIL on DWI of periprocedural brain MRI 30.0% vs 23.1%, P = 0.727; symptom recurrence rate (mean follow-up 67.1 ± 50.0 months) 2.3% vs 11.8%, P = 0.185; and significant in-stent restenosis rate (>50%) 2.3% vs 11.1%, P = 0.200. CONCLUSION: The technical safety and outcome of PTAS for PISSA were not inferior to those of radiation-naïve counterparts. PTAS for PISSA is an effective treatment for medically refractory ischaemic symptoms of HNCC patients with PISSA.

The 2023 Taiwan Stroke Society Guidelines for the management of patients with intracranial atherosclerotic disease.

Intracranial atherosclerotic disease (ICAD) is a major cause of ischemic stroke, especially in Asian populations, which has a high risk of recurrent stroke and cardiovascular comorbidities. The present guidelines aim to provide updated evidence-based recommendations for diagnosis and management of patients with ICAD. Taiwan Stroke Society guideline consensus group developed recommendations for management of patients with ICAD via consensus meetings based on updated evidences. Each proposed class of recommendation and level of evidence was approved by all members of the group. The guidelines cover six topics, including (1) epidemiology and diagnostic evaluation of ICAD, (2) nonpharmacological management of ICAD, (3) medical therapy for symptomatic ICAD, (4) endovascular thrombectomy and rescue therapy for acute ischemic stroke with underlying ICAD, (5) endovascular interventional therapy for postacute symptomatic intracranial arterial stenosis, and (6) surgical treatment of chronic symptomatic intracranial arterial stenosis. Intensive medical treatment including antiplatelet therapy, risk factor control, and life style modification are essential for patients with ICAD.

Clinical and imaging findings for the evaluation of large Rathke's cleft cysts and cystic craniopharyngiomas.

PURPOSE: Large Rathke's cleft cysts (LRCCs) and cystic craniopharyngiomas (CCPs) arise from the same embryological origin and may have similar MR presentations. However, the two tumors have different management strategies and outcomes. This study was designed to evaluate the clinical and imaging findings of LRCCs and CCPs, aiming to evaluate their pretreatment diagnosis and outcomes. METHODS: We retrospectively enrolled 20 patients with LRCCs and 25 patients with CCPs. Both tumors had a maximal diameter of more than 20 mm. We evaluated the patients' clinical and MR imaging findings, including symptoms, management strategies, outcomes, anatomic growth patterns and signal changes. RESULTS: The age of onset for LRCCs versus CCPs was 49.0 ± 16.8 versus 34.2 ± 22.2 years (p = .022); the following outcomes were observed for LRCCs versus CCPs: (1) postoperative diabetes insipidus: 6/20 (30%) versus 17/25 (68%) (p = .006); and (2) posttreatment recurrence: 2/20 (10%) versus 10/25 (40%) (p = .025). The following MR findings were observed for LRCCs versus CCPs: (1) solid component: 7/20 (35%) versus 21/25 (84%) (p = .001); (2) thick cyst wall: 2/20 (10%) versus 12/25 (48%) (p = .009); (3) intracystic septation: 1/20 (5%) versus 8/25 (32%) (p = .030); (4) snowman shape: 18/20 (90%) versus 1/25 (4%) (p < .001); (5) off-midline extension: 0/0 (0%) versus 10/25 (40%) (p = .001); and (6) oblique angle of the sagittal long axis of the tumor: 89.9° versus 107.1° (p = .001). CONCLUSIONS: LRCCs can be differentiated from CCPs based on their clinical and imaging findings, especially their specific anatomical growth patterns. We suggest using the pretreatment diagnosis to select the appropriate surgical approach and thus improve the clinical outcome.

Prevention of in-stent restenosis with drug-eluting balloons in patients with postirradiated carotid stenosis accepting percutaneous angioplasty and stenting.

OBJECTIVE: To investigate the technical safety and outcome of in-stent restenosis (ISR) prevention with drug-eluting balloon (DEB) in patients with postirradiated carotid stenosis (PIRCS) undergoing percutaneous angioplasty and stenting (PTAS). METHODS: Between 2017 and 2021, we prospectively recruited patients with severe PIRCS for PTAS. They were randomly separated into two groups based on endovascular techniques performed with and without DEB. Preprocedural and early postprocedural (within 24 hours) MRI, short-term ultrasonography (6 months after PTAS), and long-term CT angiography (CTA)/MR angiography (MRA), 12 months after PTAS, were performed. Technical safety was evaluated based on periprocedural neurological complications and the number of recent embolic ischemic lesions (REIL) in the treated brain territory on diffusion-weighted imaging of early postprocedural MRI. RESULTS: Sixty-six (30 with and 36 without DEB) subjects were enrolled, with one failure in techniques. For 65 patients in the DEB versus conventional groups, technical neurological symptoms within 1 month (1/29 (3.4%) vs 0/36; P=0.197) and REIL numbers within 24 hours (1.0±2.1 vs 1.3±1.5; P=0.592) after PTAS showed no differences. Peak systolic velocity (PSVs) on short-term ultrasonography was significantly higher in the conventional group (104.13±42.76 vs .81.95±31.35; P=0.023). The degree of in-stent stenosis (45.93±20.86 vs 26.58±8.75; P<0.001) was higher, and there were more subjects (n=8, 38.9% vs 1, 3.4%; P=0.029) with significant ISR (≥ 50%) in the conventional group than in the DEB group on long-term CTA/MRA. CONCLUSIONS: We observed similar technical safety of carotid PTAS with and without DEBs. The number of cases of significant ISR were fewer and the degree of stenosis of ISR was less in primary DEB-PTAS of PIRCS than for conventional PTAS in the 12-month follow-up.

Percutaneous transluminal angioplasty and stenting of post-irradiation stenosis of the vertebral artery.

BACKGROUND: The outcomes of percutaneous transluminal angioplasty and stenting (PTAS) in patients with medically refractory post-irradiation stenosis of the vertebral artery (PISVA) have not been clarified. AIM: This retrospective study evaluated the safety and outcomes of PTAS in patients with severe PISVA compared with their radiation-naïve counterparts (non-RT group). METHODS: Patients with medically refractory severe symptomatic vertebral artery stenosis and undergoing PTAS between 2000 and 2021 were classified as the PISVA group or the non-RT group. The periprocedural neurological complications, periprocedural brain magnetic resonance imaging, the extent of symptom relief, and long-term stent patency were compared. RESULTS: As compared with the non-RT group (22 cases, 24 lesions), the PISVA group (10 cases, 10 lesions) was younger (62.0 ± 8.6 vs 72.4 ± 9.7 years, P = 0.006) and less frequently had hypertension (40.0% vs 86.4%, P = 0.013) and diabetes mellitus (10.0% vs 54.6%, P = 0.024). Periprocedural embolic infarction was not significantly different between the non-RT group and the PISVA group (37.5% vs 35.7%, P = 1.000). At a mean follow-up of 72.1 ± 58.7 (3-244) months, there was no significant between-group differences in the symptom recurrence rate (0.00% vs 4.55%, P = 1.000) and in-stent restenosis rate (10.0% vs 12.5%, P = 1.000). CONCLUSION: PTAS of severe medically refractory PISVA is effective in the management of vertebrobasilar ischemic symptoms in head and neck cancer patients. Technical safety and outcome of the procedure were like those features in radiation-naïve patients.

Single flow diverter to manage multiple intracranial aneurysms in a parent artery.

BACKGROUND: Endovascular coil embolization has become an important method in the management of intracranial aneurysm. However, simultaneously coiling multiple intracranial aneurysms (MIAs) in unilateral parent artery in one-stage may fail or insufficient in geographic difficult aneurysm. Flow diverter (FD) has the potential to manage MIAs with nonamenable to coiling. Herein, we report periprocedural morphologic change and outcomes using single FD to manage unruptured MIAs in a parent artery. METHODS: Over a 3-year period, a total of 63 patients with 126 MIAs successful managed by single FD with complete angiographic follow-up. There were 49 women and 14 men, with ages ranging from 42 to 77 years (mean: 59 years). We retrospectively assessed the clinical data, aneurysm characteristic, angiographic and clinical outcomes of all patients and compared with 171 patients with single aneurysm managed by FD. RESULTS: Sixty-one patients with 118 aneurysms (94%) located in internal carotid artery or middle cerebral artery (n = 4, 3%), two patients with four aneurysms (4%) were found in the basilar artery. The mean aneurysm size was 5.6 mm (range from 1.8 to 38 mm). Mean angiographic follow-up was 14 months. Complete obliteration of aneurysm was achieved in 102 aneurysms (83%), subtotal or partial aneurysm obliteration was demonstrated in 18 aneurysms (15%), unchanged aneurysm morphology in three (2%). Aneurysm morphology synchronized alteration in 55 patients (87%), other eight patients (13%) with 16 aneurysms showed different morphologic alteration in angiographic follow-up. Four patients (6.3%) had intraprocedural ischemic complication. During the follow-up period, 61 patients (97%) were neurologic stable; there was no hemorrhagic or ischemic event. CONCLUSION: Single FD was feasible to treat MIAs in a parent artery with both effective and safe in one-stage management. Most aneurysms synchronized alteration of morphology in a mid-term follow-up. The procedure was almost the same with FD managing single aneurysm, but longer FD is needed in MIAs.

Outflow Patency Correlates with Radiosurgical Outcomes of Lateral Sinus Dural Arteriovenous Fistula.

OBJECTIVE: To explore the impact of outflow patency on radiosurgical outcomes of lateral sinus dural arteriovenous fistulas (DAVFs). METHODS: We retrospectively examined 83 lateral sinus DAVFs treated with Gamma Knife radiosurgery (GKRS) between 1995 and 2020. Two neuroradiologists blinded to the therapeutic outcomes served as imaging evaluators on pre-GKRS digital subtraction angiography and magnetic resonance images. The sinovenous outflow of lateral sinus DAVF was scored using combined conduit score (CCS), ranging from 0 (total occlusion) to 8 (full patency). The patients' follow-up magnetic resonance and digital subtraction angiography images were used to validate the radiosurgical outcomes (obliteration or non-obliteration) of lateral sinus DAVF. Cox regression and Kaplan-Meier analyses were performed to determine the correlations between the variables and outcomes. RESULTS: Among the 83 cases, 60 (72%) lateral sinus DAVFs achieved obliteration after a GKRS at a median latency period of 24.5 months. After adjustment for aggressive presentation, cortical venous reflux, straight sinus reflux, and optic nerve sheath enlargement, a CCS of >6 was independently associated with lateral sinus DAVF obliteration (hazard ratio: 2.335, P = 0.007). The estimated 36-month probabilities of obliteration were 80% versus 53.6% for lateral sinus DAVFs with a CCS of >6 versus ≤6. CONCLUSIONS: Lateral sinus DAVFs with a CCS of >6, indicating a nearly patent sinovenous outflow, were more likely to be obliterated after GKRS. Sinovenous outflow patency is a factor associated with therapeutic outcomes in radiosurgery for lateral sinus DAVFs.

Influence of angioplasty and stenting on intracranial artery stenosis: preliminary results of high-resolution vessel wall imaging evaluation.

OBJECTIVES: To investigate whether the imaging changes on high-resolution vessel wall imaging (HR-VWI) in patients before and after percutaneous transluminal angioplasty and stenting (PTAS) contribute to predicting the clinical outcome. METHODS: The study included 24 severe intracranial artery stenosis (SICAS) patients undergoing PTAS with Wingspan Stent between 2018 and 2020 and had a 1-year follow-up. Three HR-VWI sessions (preprocedural, early [within 24 h], and delayed postprocedural [134.7 ± 27.1 days)]) in each subject were performed with 3-Tesla MRI. We evaluated periprocedural HR-VWI changes in patients with and without recurrent cerebral ischemic symptoms (RCIS) within 1-year follow-up. RESULTS: On CE-T1WI of the patients without RCIS, a significant decrease in enhanced area was observed on early postprocedural (0.04 ± 0.02 cm2, p = 0.001) and delayed postprocedural (0.04 ± 0.02 cm2; p = 0.001) HR-VWI compared to preprocedural (0.07 ± 0.02 cm2) HR-VWI. Patients with RCIS demonstrated no significant loss of enhanced area on CE-T1WI of early postprocedural HR-VWI (p = 0.180). Significant decreases in calibrated T1 signals were observed in both presence (1.77 ± 0.70 vs. 0.79 ± 0.52; p = 0.018) and absence (1.42 ± 0.62 vs. 0.83 ± 0.40; p = 0.001) of RCIS in early postprocedural HR-VWI. CONCLUSION: The preliminary results showed the presence of reduced contrast enhancement immediately after PTAS may indicate less recurrent stroke events within 1 year. Further studies are necessary to confirm the phenomena in a longer observation period. KEY POINTS: • Early postprocedural high-resolution vessel imaging (HR-VWI) within 24 h can effectively predict a 1-year outcome following intracranial stenting. • For stenotic lesions after stenting without reduced contrast enhancement on HR-VWI within 24 h may need closer clinical surveillance for potentially higher risk of stroke events within 1 year.

Sinovenous outflow in lateral sinus dural arteriovenous fistulas after stereotactic radiosurgery: a retrospective longitudinal imaging study.

PURPOSE: To investigate sinovenous outflow restriction (SOR) in lateral sinus dural arteriovenous fistulas (LSDAVFs) after Gamma Knife radiosurgery (GKRS) and its association with complete obliteration. METHODS: We retrospectively (1995-2019) enrolled 39 patients with LSDAVFs who had undergone GKRS alone and evaluated their angiography and magnetic resonance imaging (MRI) before and after GKRS. The LS conduits ipsilateral and contralateral to the DAVFs were scored using a 5-point scoring system, with scores ranging from 0 (total occlusion) to 4 (fully patent). SOR was defined by a conduit score < 2. Demographics, imaging features, and outcomes were compared between patients with and without ipsilateral SOR after GKRS. Logistic regression analysis was performed to estimate the odds ratio (OR) for obliteration with the imaging findings. RESULTS: After a median angiographic follow-up of 28 months for the 39 patients, the ipsilateral LS became more restrictive (median conduit score before and after GKRS: 2 vs. 1, p = .011). Twenty-one patients with ipsilateral SOR after GKRS had a significantly lower obliteration rate (52.4% vs. 94.4%, p = .005) than those without SOR. Follow-up SOR was independently associated with a lower obliteration rate (OR 0.05, p = .017) after adjustment for age, cortical venous reflux, and absent sinus flow void on MRI. CONCLUSION: This study demonstrates a restrictive change of outflow in LSDAVFs after GKRS and a lower obliteration rate in patients with SOR. Follow-up imaging for SOR may help predict outcomes of these patients.

Shortened cerebral circulation time correlates with seizures in brain arteriovenous malformation: a cross-sectional quantitative digital subtraction angiography study.

OBJECTIVE: Seizure is the most common clinical presentation in patients with nonhemorrhagic brain arteriovenous malformations (BAVMs) and it influences their quality of life. Angioarchitectural analysis of the seizure risk for BAVMs is subjective and does not consider hemodynamics. This study aimed to investigate the angioarchitectural and hemodynamic factors that may be associated with seizure in patients with BAVMs. METHODS: From 2011 to 2019, 104 patients with supratentorial BAVMs without previous hemorrhage or treatment were included and grouped according to the initial presentation of seizure. Their angiograms and MRI results were analyzed for morphological characteristics and quantitative digital subtraction angiography (QDSA) parameters. Modified cerebral circulation time (mCCT) was defined as the difference between the bolus arrival time of the ipsilateral cavernous internal carotid artery and the parietal vein on lateral DSA. Logistic regression analysis was performed to estimate the odds ratio (OR) for BAVMs presenting with seizure. RESULTS: The seizure group had shorter mCCT (1.98 s vs. 2.44 s, p = 0.005) and more BAVMs with temporal location (45% vs. 30.8%, p = 0.013), neoangiogenesis (55% vs. 33%, p = 0.03), and long draining veins (95% vs. 72%, p = 0.004) than did the nonseizure group. Shorter mCCT (OR: 3.4, p = 0.02), temporal location (OR: 13.4, p < 0.001), and neoangiogenesis (OR: 4.7, p = 0.013) were independently associated with higher risks of seizure, after adjustments for age, gender, BAVM volume, and long draining vein. CONCLUSIONS: Shorter mCCT, temporal location, and neoangiogenesis were associated with epileptic BAVMs. QDSA can objectively evaluate hemodynamic changes in epileptic BAVMs. KEY POINTS: • Quantitative digital subtraction angiography may be used to evaluate the hemodynamic differences between brain arteriovenous malformations presenting with and without seizure. • BAVMs with temporal location, neoangiogenesis, and shortened cerebral circulation time were more likely to present with seizure.

Iatrogenic retroperitoneal hematoma as an access-site complication of neurointervention.

BACKGROUND: To evaluate the clinical and imaging presentation, management, and outcome of iatrogenic retroperitoneal hematomas (IRPHs) during a series of neurointerventional procedures (NIPs). METHODS: Six IRPH patients with complications, including five renal subcapsular hematomas (RSH) and one retroperitoneal hemorrhage, were observed among 2290 NIPs performed at our hospital from 2000 through 2020. The medical records, neurointerventional techniques, imaging data, and management of these six IRPH patients were retrospectively reviewed. All six patients received preprocedural dual antiplatelet medication and intraprocedural heparinization. RESULTS: All patients underwent right femoral access. The guidewires were not handled under full course fluoroscopy monitoring. The most common symptom of IRPH was periprocedural flank/abdominal pain (6/6, 100%), including five on the left side (83.3%). Hypotension or shock was observed in three patients (50%). Two patients (33%) were diagnosed intraoperatively by sonogram and received on-site treatment, whereas the other four were diagnosed by postprocedural abdominal computed tomography. Active extravasation from a renal artery was diagnosed by angiogram in the five patients with RSH and was successfully treated with embolization. Multiple bleeders in the branches of the renal artery were noted in three RSH patients (60%). The patient with retroperitoneal hematoma was treated conservatively. CONCLUSION: Unexplained periprocedural or postprocedural abdominal/flank pain, especially contralateral to the femoral access side of the NIPs, should raise the possibility of IRPH. To prevent IRPH, the authors suggest using full visual fluoroscopic monitoring for guidewire navigation during femoral catheterization of NIPs.

Flow diverter manages very small aneurysm of the internal carotid artery.

BACKGROUND: Endovascular aneurysm coiling is a minimally invasive method to manage intracranial aneurysms. However, aneurysm coiling may fail in very small aneurysms (VSAs); thus, flow diverter (FD) is recommended as an alternative in these difficult aneurysms. Herein, we report our experience and outcomes of FD to treat VSA of the internal carotid artery (ICA). METHODS: Over a 3-year period, a total of 70 patients with 87 unruptured VSAs of the ICA were managed by FD. There were 54 men and 16 women, with a mean age of 57 (range, 41-75) years. We retrospectively assessed the clinical data, aneurysm characteristics, and angiographic as well as clinical outcomes of patients treated by FD and compared with larger aneurysms. RESULTS: Fifty aneurysms (58%) were located in the supraclinoid ICA, followed by paraclinoid ICA (n = 31, 36%) and cavernous ICA (n = 6, 7%). Most aneurysms (n = 72, 83%) were between 2 and 3 mm in size. The mean aneurysm size was 2.3 mm (range, 1.5-3 mm). Follow-up angiographic data (mean, 13 months) were available in 54 patients with 68 aneurysms. Successful FD deployment in an ideal position to bride aneurysm was achieved in 86 of 87 aneurysms (99%). Complete obliteration (CO) was achieved in 63 aneurysms (93%). Compared with larger aneurysms (>3 mm), VSAs had the tendency to achieve CO ( p < 0.05) in a midterm follow-up. Two patients (2.8%) had intraprocedural complications, including in-stent thrombosis (n = 1) and distal embolism (n = 1). One patient (1.4%) suffered from mild limb weakness. CONCLUSION: The use of FD to manage VSA was technically feasible, and the procedure was simpler than those of larger aneurysms. FD stenting of VSAs was confirmed to be effective and safe and had higher CO rate than those in larger aneurysms in a midterm angiographic follow-up.

Flow-diverter stent to manage intracranial aneurysms: A single center experience.

BACKGROUND: Endovascular coil embolization is an important method for managing intracranial aneurysms. However, aneurysm coiling may fail or be insufficient in geographically difficult aneurysms. A flow-diverter stent (FDS) is an alternative in these difficult coiling aneurysms. Thus, this study reports the experience and outcome of FDS management of intracranial aneurysms. METHODS: Over 29 months, FDS treated 125 patients with 163 intracranial unruptured aneurysms. This study enrolled 31 men and 94 women, ranging from 17 to 81 years (mean, 58 years). Clinical data, aneurysm characteristics, and angiographic and clinical outcomes of patients treated by FDS were retrospectively assessed. RESULTS: The current study found 151 (93%) aneurysms in the internal carotid artery. Most aneurysms (n = 118; 72%) were small (<7 mm). The mean aneurysm size was 6.2 mm (range, 2-38 mm). Follow-up angiography was available in 53 patients with 74 aneurysms (mean, 13 months). Successful FDS deployment in an ideal position was found in 125 of 130 patients (96%). Complete obliteration (CO) was achieved in 58 aneurysms (78%) in the mean 13-month angiographic follow-up. Smaller aneurysms (<7 mm) had a CO tendency than larger aneurysms (p < 0.01) in midterm follow-up. Seven patients (5.6%) had intraprocedural complications (in-stent thrombosis, three patients; distal embolic, two patients; iatrogenic carotid-cavernous fistula, and subarachnoid hemorrhage, one patient). Two patients (1.6%) suffered from permanent procedure-related morbidity (n = 1) or mortality (n = 1). No late hemorrhagic events or stent displacement occurred during the follow-up period. CONCLUSION: Despite few procedural complications and some pieces of evidence of insufficient aneurismal treatment in a midterm angiographic follow-up, FDS was effective and safe in managing intracranial unruptured aneurysms, particularly in smaller aneurysms, which had better CO than larger ones.

Imaging Markers Associated With Radiation-Induced Changes in Brain Arteriovenous Malformations After Radiosurgery.

BACKGROUND: Radiation-induced changes (RICs) in brain tissue, seen as increased perinidal T2-weighted hyperintensity on MRI, are commonly observed in patients with brain arteriovenous malformations (BAVMs) within 2 years after Gamma Knife (Elekta) radiosurgery (GKRS). OBJECTIVE: To explore the imaging markers associated with RICs in patients with BAVMs. METHODS: We retrospectively included 106 treatment-naïve patients with BAVMs who received GKRS alone between 2011 and 2018 and had ≥24 months of clinical and MRI follow-up. Pre-GKRS angiography and MRIs were analyzed for morphological characteristics and quantitative digital subtraction angiography parameters. RIC severity was categorized as mild (grade I), moderate (grade II), or severe (grade III). Firth logistic regression analysis was conducted to determine the associations between the parameters and RICs. RESULTS: Among the 106 patients, 83 (78.3%) developed RICs, with 16 categorized as grade I, 62 as grade II, and 5 as grade III. RICs were symptomatic in 19 patients (17.9%). In multivariable models, BAVMs with a volume of >5 cm3 (odds ratio [OR]: 4.322, P = .024) and neoangiogenesis on angiography before treatment (OR: 3.846, P = .029), and thrombus within nidus or drainage vein on follow-up MRI (OR: 3.679, P = .001) were independently associated with grade II or III RICs. Symptomatic RICs were more likely to develop in basal ganglia or brainstem. CONCLUSION: Large BAVMs and neoangiogenesis were associated with moderate to severe RICs in treatment-naïve patients with BAVMs. Our findings may assist with the complication risk assessment for these patients.

Risk factors of recurrent carotid blowout syndrome and strategy of endovascular management.

BACKGROUND: Carotid blowout syndrome (CBS) is a catastrophic complication after aggressive head and neck cancer treatment. Endovascular embolization is an effective modality to manage CBS. However, some CBS may have recurrent CBS (rCBS) after endovascular management. This study aims to report the potential rCBS risk and endovascular management strategy. METHODS: Of the 225 patients with CBS referred for embolization in 13 years, 31 men and one woman (mean age, 55 years) with 35 rCBS with pseudoaneurysms formation were identified after endovascular management. Moreover, the rCBS preembolization angioarchitecture, rCBS cause, rCBS time interval, embolic materials selection, and final embolization clinical/angiographic outcomes were retrospectively analyzed. RESULTS: rCBS with pseudoaneurysm due to disease progression (DP) occurred in 17 patients, while 15 patients had insufficient embolization (IE) with 18 rCBS. The mean rCBS timing interval was 76 days with 129 and 12 days due to DP or IE. The most common rCBS locations were the carotid bulb and the main trunk of the external carotid artery (n = 20, 57%), followed by internal carotid artery (n = 8, 23%), distal branch of the external carotid artery (n = 4, 11%), and common carotid artery (n = 3, 9%). Endovascular management was technically successful in all patients by reconstruction (n = 7, 20%) or destruction (n = 28, 80%) techniques. Three patients (9%) had procedure-related complications. No rCBS was observed in all affected arteries after the last embolization in a mean 11-month clinical follow-up. CONCLUSION: rCBS may result from DP or IE. The common location of IE-related rCBS usually occurred in the carotid branches. It occurred within two weeks of CBS largely because of the underestimation of the extension of the affected carotid artery. In addition, DP is natural in head and neck cancer after aggressive treatment. Thus, endovascular management remained an effective method to manage rCBS.

Percutaneous transluminal angioplasty and stenting of post-irradiated stenosis of subclavian artery.

BACKGROUND/PURPOSE: The therapeutic efficacy of percutaneous transluminal angioplasty and stenting (PTAS) of post-irradiated stenosis of subclavian artery (PISSA) was not well clarified. This retrospective study was designed to evaluate the technical safety and outcome of the patients of severe symptomatic PISSA accepted PTAS. METHODS: Between 2000 and 2019, 16 cases with 17 lesions of symptomatic and medically refractory PISSA accepted PTAS were included. We evaluated their technical success, peri-procedural complications and diffusion-weight imaging (DWI) of brain magnetic resonance imaging (MRI), results of symptom relief, and long-term stent patency. RESULTS: The stenosis of the 17 stenotic lesions were 81.2 ± 11.1%. The most common symptom of the 16 patients was dizziness (14/16, 87.5%). All successfully accepted PTAS without neurological complication and had symptom relief after PTAS (17/17, 100%). Of the 12 patients accepted pre-procedural and early post-procedural MRI follow-up, 2 patients had an asymptomatic tiny acute embolic infarct in the territory of vertebrobasilar system. In a 51.9 ± 54.9 months follow-up, all patients had no severe restenosis and no recurrent vertebrobasilar ischemic symptoms. CONCLUSION: For patients with PISSA and medically refractory ischemic symptoms, PTAS can be an effective alternative management.

Application of Flat-Panel Volume Computed Tomography to Evaluate Cerebral Hemorrhage After Mechanical Thrombectomy of Acute Embolic Stroke of the Anterior Circulation.

OBJECTIVE: The aim of the study was to evaluate cerebral hemorrhage (CH) and contrast media leakage (CML or commonly synonymous with "contrast staining") differentiation on flat-panel volume computed tomography (FPVCT) after intra-arterial mechanical thrombectomy. METHODS: We evaluated patients with hyperattenuation on FPVCT after intra-arterial mechanical thrombectomy between 2018 and 2021 by multiple parameters on CT angiography, FPVCT, CT, and/or magnetic resonance imaging. RESULTS: The CH (n = 43) versus CML (n = 24) groups revealed: (1) regional anatomical characteristics (preserved and distorted): 7 of 43 (9.6%) and 36 of 43 (83.7%) versus 22 of 24 (91.7%) and 2 of 24 (8.3%, P < 0.001); (2) thrombus in proximal two-thirds versus distal one-thirds M1 segment of middle cerebral artery (preserved and distorted): 17 of 21 (81.0%) and 4 of 21 (19.0%) versus 5 of 11 (45.5%) and 6 of 11 (54.5%, P = 0.040); and (3) average density ratio: 1.83 ± 0.65 versus 1.35 ± 0.13 (P = 0.004). CONCLUSIONS: Contrast media leakage can be differentiated from CH by preserved regional anatomical characteristics and relatively low average density ratio on FPVCT. Patients with CML who have embolism in proximal two thirds of M1 segment are more likely to develop hyperattenuation with preserved regional anatomy.