In the past 20 years, with the continuous integration of cutting-edge technologies such as new equipments, new materials and artificial intelligence, neurointerventional radiology has developed rapidly. The therapeutic effect of neurointerventional radiology on cerebrovascular diseases such as intracranial aneurysms, cerebral arteriovenous malformations, dural arteriovenous fistulas, acute large vessel occlusive stroke, and head and carotid atherosclerotic stenosis has been continuously improved, and the indications have been gradually expanded. Neurointerventional radiology has become the first-line or even preferred treatment for some diseases. This article reviews the clinical application status and possible development trend of neurointerventional radiology, so as to provide references for clinical practice.

Objective:To investigate the efficacy and safety of off-label use of flow diverters (FDs) in aneurysms beyond the circle of Willis.Methods:Seventy-one patients with aneurysms beyond the circle of Willis treated with FDs from January 2016 to September 2023 at Department of Cerebrovascular Surgery, Neurosurgery Center (Zhujiang Hospital of Southern Medical University), Department of Neurosurgery (Guangdong Provincial People's Hospital), Department of Neurosurgery (First Affiliated Hospital of Chongqing Medical University), and Department of Neurosurgery (Beijing Tiantan Hospital, Capital Medical University) were selected. The clinical and imaging data of these patients were analyzed retrospectively, and the clinical characteristics, aneurysm characteristics, endovascular treatments, perioperative complications, and clinical and imaging follow-up results were summarized and analyzed.Results:Among the 71 patients, 22 (31.0%) had ischemic stroke history and 43 (60.6%) had hypertension history. A total of 76 aneurysms were found, including 5 aneurysms (6.6%) at the anterior communicating artery, 10 (13.2%) at the anterior cerebral artery, 53 (69.7%) at the middle cerebral artery, and 8 (10.5%) at the posterior cerebral artery. The median aneurysm size (Inter Quartile Range) was 5.65 (3.63, 10.12) mm, and mean diameter of the parent artery was (2.70±0.57) mm. A total of 80 FDs were used, including 38 (47.5%) Pipeline embolization devices and 42 (52.5%) Tubridge embolization devices; the implantation success rate was 98.8% (79/80). Seven patients (9.9%) had perioperative complications, of which 2 (2.8%) were permanent (1 patient with visual field defect and 1 patient with intracranial hemorrhage). Seventy-one patients had clinical follow-up for (19.73±11.90) months, of which 68 patients (95.8%) had good outcome (modified Rankin scale score of 0-2), 10 patients (14.1%) had ischemic complications, and one patient (1.4%) had hemorrhage complications. Sixty-seven aneurysms (88.2%) underwent angiographic follow-up for 7 (6-12) months, of which 44 aneurysms (65.7%) were completely occluded and 10 (14.9%) had in-stent stenosis.Conclusion:The results of this study preliminarily confirm that off-label use of FDs is relatively safe and effective in aneurysms beyond the circle of Willis.

Objective:To evaluate the efficacy and safety of intrasaccular flow disruptor in wide-necked intracranial aneurysms.Methods:One hundred and seventeen patients with wide-necked intracranial aneurysms treated with intrasaccular flow disruptor were collected from Department of Neurointervention (First Affiliated Hospital of Zhengzhou University), Department of Neurosurgery (Beijing Tiantan Hospital, Capital Medical University), Department of Cerebrovascular Surgery, Neurosurgery Center (Zhujiang Hospital, Southern Medical University), and Department of Neurosurgery (First Affiliated Hospital of Harbin Medical University) from August 2022 to March 2024. Raymond-Roy Occlusion Classification (RROC) was employed to evaluate aneurysm embolization immediately after procedure; cranial CT or MRI within 48 hours of embolization were performed to identify any new intracranial hemorrhage, subarachnoid hemorrhage, or new symptomatic cerebral infarction related to the intracranial aneurysms. Modified Rankin Scale (mRS) was used to assess the neurological function at discharge. Imaging follow-up and outpatient follow-up were performed at 6 months after embolization to evaluate the aneurysm occlusion degree and complications.Results:A total of 117 intrasaccular flow disruptors were implanted in 117 patients, with a technical success rate of 100%; 115 patients (98.3%) enjoyed successful one-time release of their disruptors, and 2 patients (1.7%) required retrieval and redirection of the disruptors before second successful attempt. Flow disruptor plus stent was performed in 13 patients (11.1%). Immediately after procedure, RROC grading I was noted in 3 patients, grading II in 51 patients and grading III in 63 patients. Cranial CT or MRI within 48 hours of embolization indicated no new intracranial hemorrhage, subarachnoid hemorrhage, or symptomatic cerebral infarction related to the intracranial aneurysms. All patients had mRS score of 0 at discharge. Eighty-three patients completed a 6-month follow-up (RROC grading I in 41 patients, grading II in 33 patients and grading III in 9 patients), without ischemic or hemorrhagic adverse events.Conclusion:The results of this study preliminarily suggest that intrasaccular flow disruptor is effective and safe in wide-necked intracranial aneurysms.

Objective:To evaluate the efficacy and safety of Neuroform Atlas stent-assisted coil embolization in patients with middle cerebral artery bifurcation aneurysms.Methods:A retrospective analysis was performed; the clinical data of 46 patients with middle cerebral artery bifurcation aneurysms accepted Neuroform Atlas stent-assisted coil embolization in First Affiliated Hospital of Zhengzhou University, Beijing Tiantan Hospital Affiliated to Capital Medical University, First Affiliated Hospital of Harbin Medical University, Zhujiang Hospital of Southern Medical University and First Affiliated Hospital of Chongqing Medical University from January 2022 to March 2024 were collected. There were 28 ruptured aneurysms (60.87%) and 18 unruptured aneurysms (39.13%). Follow-up was performed for more than 3 months; Raymond-Roy grading was used to evaluate the aneurysm embolization immediately after embolization and during follow-up; perioperative hemorrhagic or ischemic complications were recorded; modified Rankin Scale (mRS) was used to evaluate the prognosis of the patients at discharge and during follow-up (mRS score≤2: good prognosis, and mRS score>2: poor prognosis).Results:Coil embolization was successful in all 46 patients. DSA immediately after embolization showed that 41 patients (89.13%) had completely occluded aneurysms (Raymond-Roy grading I), 2 patients (4.35%) had residual aneurysm neck (Raymond-Roy grading Ⅱ) and 3 patients (6.52%) had partially occluded aneurysms (Raymond-Roy grading Ⅲ). Perioperative complications occurred in 5 patients, including 2 with postoperative cerebral infarction, 1 with hydrocephalus, 1 with postoperative pneumonia leading to respiratory failure, and 1 with stent thrombosis during embolization. Both at discharge and 3 months after embolization, 43 patients (93.48%) had good prognosis and 3 patients (6.52%) had poor prognosis. No obvious ischemic complications (such as stent restenosis) or hemorrhagic complications (such as re-rupture of the aneurysms) were found in all patients. Thirty patients (65.22%) had imaging follow-up for 6-12 months: 26 (86.67%) had Raymond-Roy grading I, 3 (10.00%) had Raymond-Roy grading II, and 1 (3.33%) had Raymond-Roy grading III.Conclusion:Neuroform Atlas stent-assisted coil embolization has good short-term efficacy and high safety in middle cerebral artery bifurcation aneurysms, but long-term follow-up observation is still needed to verify its efficacy.

Objective:To explore the efficacy and safety of embolization of anterior cranial fossa dural arteriovenous fistula (ACF-DAVF) via different arterial approaches, and provide evidence for individualized treatment of ACF-DAVF. Methods:A retrospective study was performed; 25 patients with ACF-DAVF admitted to Department of Cerebrovascular Surgery, Neurosurgery Center, Zhujiang Hospital, Southern Medical University from January 2020 to December 2023 were enrolled. Vascular approaches, including the anterior cerebral artery ( n=7), facial artery ( n=3), middle meningeal artery ( n=8), ophthalmic artery ( n=6), and vein ( n=1), were selected based on angioarchitectural features and microcatheter accessibility. Fistula and proximal draining vein occlusions were confirmed by immediate post-embolization digital subtraction angiography (DSA), and perioperative complications were recorded. At a 6-month follow-up, prognoses were assessed by modified Rankin Scale (mRS), and DSA or MRA was performed to detect the recurrence of ACF-DAVF. Results:Six patients had complete embolization and 2 patients had near-total embolization of the fistula and proximal draining vein immediately after embolization via middle meningeal artery approach; 4 patients achieved complete embolization and 2 patients achieved near-total embolization via ophthalmic artery approach; 6 patients achieved complete embolization and one patient achieved near-total embolization via anterior cerebral artery approach; 3 patients achieved complete embolization via facial artery approach; one patient achieved complete embolization via venous approach. No perioperative intracranial hemorrhage or central retinal artery occlusion was noted. Follow-up for 6 months was performed in 25 patients: mRS score was 0 in 19 patients, 1 in 2 patients, and 2 in 4 patients; DSA in 19 patients and MRA in 6 patients indicated no ACF-DAVF recurrence. Conclusion:Based on the angioarchitectural features and microcatheter accessibility, individualized selection of vascular approaches for ACF-DAVF embolization can achieve better efficacy and safety.

Objective:To investigate the efficacy and safety of off-label use of flow diverters (FDs) in aneurysms beyond the circle of Willis.Methods:Seventy-one patients with aneurysms beyond the circle of Willis treated with FDs from January 2016 to September 2023 at Department of Cerebrovascular Surgery, Neurosurgery Center (Zhujiang Hospital of Southern Medical University), Department of Neurosurgery (Guangdong Provincial People's Hospital), Department of Neurosurgery (First Affiliated Hospital of Chongqing Medical University), and Department of Neurosurgery (Beijing Tiantan Hospital, Capital Medical University) were selected. The clinical and imaging data of these patients were analyzed retrospectively, and the clinical characteristics, aneurysm characteristics, endovascular treatments, perioperative complications, and clinical and imaging follow-up results were summarized and analyzed.Results:Among the 71 patients, 22 (31.0%) had ischemic stroke history and 43 (60.6%) had hypertension history. A total of 76 aneurysms were found, including 5 aneurysms (6.6%) at the anterior communicating artery, 10 (13.2%) at the anterior cerebral artery, 53 (69.7%) at the middle cerebral artery, and 8 (10.5%) at the posterior cerebral artery. The median aneurysm size (Inter Quartile Range) was 5.65 (3.63, 10.12) mm, and mean diameter of the parent artery was (2.70±0.57) mm. A total of 80 FDs were used, including 38 (47.5%) Pipeline embolization devices and 42 (52.5%) Tubridge embolization devices; the implantation success rate was 98.8% (79/80). Seven patients (9.9%) had perioperative complications, of which 2 (2.8%) were permanent (1 patient with visual field defect and 1 patient with intracranial hemorrhage). Seventy-one patients had clinical follow-up for (19.73±11.90) months, of which 68 patients (95.8%) had good outcome (modified Rankin scale score of 0-2), 10 patients (14.1%) had ischemic complications, and one patient (1.4%) had hemorrhage complications. Sixty-seven aneurysms (88.2%) underwent angiographic follow-up for 7 (6-12) months, of which 44 aneurysms (65.7%) were completely occluded and 10 (14.9%) had in-stent stenosis.Conclusion:The results of this study preliminarily confirm that off-label use of FDs is relatively safe and effective in aneurysms beyond the circle of Willis.

Objective:To evaluate the efficacy and safety of intrasaccular flow disruptor in wide-necked intracranial aneurysms.Methods:One hundred and seventeen patients with wide-necked intracranial aneurysms treated with intrasaccular flow disruptor were collected from Department of Neurointervention (First Affiliated Hospital of Zhengzhou University), Department of Neurosurgery (Beijing Tiantan Hospital, Capital Medical University), Department of Cerebrovascular Surgery, Neurosurgery Center (Zhujiang Hospital, Southern Medical University), and Department of Neurosurgery (First Affiliated Hospital of Harbin Medical University) from August 2022 to March 2024. Raymond-Roy Occlusion Classification (RROC) was employed to evaluate aneurysm embolization immediately after procedure; cranial CT or MRI within 48 hours of embolization were performed to identify any new intracranial hemorrhage, subarachnoid hemorrhage, or new symptomatic cerebral infarction related to the intracranial aneurysms. Modified Rankin Scale (mRS) was used to assess the neurological function at discharge. Imaging follow-up and outpatient follow-up were performed at 6 months after embolization to evaluate the aneurysm occlusion degree and complications.Results:A total of 117 intrasaccular flow disruptors were implanted in 117 patients, with a technical success rate of 100%; 115 patients (98.3%) enjoyed successful one-time release of their disruptors, and 2 patients (1.7%) required retrieval and redirection of the disruptors before second successful attempt. Flow disruptor plus stent was performed in 13 patients (11.1%). Immediately after procedure, RROC grading I was noted in 3 patients, grading II in 51 patients and grading III in 63 patients. Cranial CT or MRI within 48 hours of embolization indicated no new intracranial hemorrhage, subarachnoid hemorrhage, or symptomatic cerebral infarction related to the intracranial aneurysms. All patients had mRS score of 0 at discharge. Eighty-three patients completed a 6-month follow-up (RROC grading I in 41 patients, grading II in 33 patients and grading III in 9 patients), without ischemic or hemorrhagic adverse events.Conclusion:The results of this study preliminarily suggest that intrasaccular flow disruptor is effective and safe in wide-necked intracranial aneurysms.

Objective:To evaluate the efficacy and safety of Neuroform Atlas stent-assisted coil embolization in patients with middle cerebral artery bifurcation aneurysms.Methods:A retrospective analysis was performed; the clinical data of 46 patients with middle cerebral artery bifurcation aneurysms accepted Neuroform Atlas stent-assisted coil embolization in First Affiliated Hospital of Zhengzhou University, Beijing Tiantan Hospital Affiliated to Capital Medical University, First Affiliated Hospital of Harbin Medical University, Zhujiang Hospital of Southern Medical University and First Affiliated Hospital of Chongqing Medical University from January 2022 to March 2024 were collected. There were 28 ruptured aneurysms (60.87%) and 18 unruptured aneurysms (39.13%). Follow-up was performed for more than 3 months; Raymond-Roy grading was used to evaluate the aneurysm embolization immediately after embolization and during follow-up; perioperative hemorrhagic or ischemic complications were recorded; modified Rankin Scale (mRS) was used to evaluate the prognosis of the patients at discharge and during follow-up (mRS score≤2: good prognosis, and mRS score>2: poor prognosis).Results:Coil embolization was successful in all 46 patients. DSA immediately after embolization showed that 41 patients (89.13%) had completely occluded aneurysms (Raymond-Roy grading I), 2 patients (4.35%) had residual aneurysm neck (Raymond-Roy grading Ⅱ) and 3 patients (6.52%) had partially occluded aneurysms (Raymond-Roy grading Ⅲ). Perioperative complications occurred in 5 patients, including 2 with postoperative cerebral infarction, 1 with hydrocephalus, 1 with postoperative pneumonia leading to respiratory failure, and 1 with stent thrombosis during embolization. Both at discharge and 3 months after embolization, 43 patients (93.48%) had good prognosis and 3 patients (6.52%) had poor prognosis. No obvious ischemic complications (such as stent restenosis) or hemorrhagic complications (such as re-rupture of the aneurysms) were found in all patients. Thirty patients (65.22%) had imaging follow-up for 6-12 months: 26 (86.67%) had Raymond-Roy grading I, 3 (10.00%) had Raymond-Roy grading II, and 1 (3.33%) had Raymond-Roy grading III.Conclusion:Neuroform Atlas stent-assisted coil embolization has good short-term efficacy and high safety in middle cerebral artery bifurcation aneurysms, but long-term follow-up observation is still needed to verify its efficacy.

Objective:To explore the efficacy and safety of embolization of anterior cranial fossa dural arteriovenous fistula (ACF-DAVF) via different arterial approaches, and provide evidence for individualized treatment of ACF-DAVF. Methods:A retrospective study was performed; 25 patients with ACF-DAVF admitted to Department of Cerebrovascular Surgery, Neurosurgery Center, Zhujiang Hospital, Southern Medical University from January 2020 to December 2023 were enrolled. Vascular approaches, including the anterior cerebral artery ( n=7), facial artery ( n=3), middle meningeal artery ( n=8), ophthalmic artery ( n=6), and vein ( n=1), were selected based on angioarchitectural features and microcatheter accessibility. Fistula and proximal draining vein occlusions were confirmed by immediate post-embolization digital subtraction angiography (DSA), and perioperative complications were recorded. At a 6-month follow-up, prognoses were assessed by modified Rankin Scale (mRS), and DSA or MRA was performed to detect the recurrence of ACF-DAVF. Results:Six patients had complete embolization and 2 patients had near-total embolization of the fistula and proximal draining vein immediately after embolization via middle meningeal artery approach; 4 patients achieved complete embolization and 2 patients achieved near-total embolization via ophthalmic artery approach; 6 patients achieved complete embolization and one patient achieved near-total embolization via anterior cerebral artery approach; 3 patients achieved complete embolization via facial artery approach; one patient achieved complete embolization via venous approach. No perioperative intracranial hemorrhage or central retinal artery occlusion was noted. Follow-up for 6 months was performed in 25 patients: mRS score was 0 in 19 patients, 1 in 2 patients, and 2 in 4 patients; DSA in 19 patients and MRA in 6 patients indicated no ACF-DAVF recurrence. Conclusion:Based on the angioarchitectural features and microcatheter accessibility, individualized selection of vascular approaches for ACF-DAVF embolization can achieve better efficacy and safety.

Flow diverter (FD) devices have gradually become the mainstream approach for interventional treatment of intracranial aneurysms. In-stent stenosis (ISS) is a common complication after FD implantation, which can lead to ischemic events and affect the prognosis of patients. Current studies have shown that ISS occurrence is closely related to hemodynamic changes. From the perspective of hemodynamics, this article reviews the research progress of mechanisms, evaluation methods and treatments of ISS after FD implantation, in order to provide reference for clinical practice.