Seitzhan Aidarov

Background. The transfemoral approach has traditionally been the standard vascular access route for diagnostic and therapeutic neuroendovascular procedures. However, unfavorable iliofemoral anatomy, severe aortoiliac disease, complex aortic arch configurations, and access-site limitations may render transfemoral catheterization technically challenging or unsuccessful. The transradial approach, widely adopted in interventional cardiology, has emerged as an alternative access strategy in neurointerventions. Objective. To describe the technical aspects and practical considerations of transradial approach in neurointerventional procedures in a technical note with an illustrative case cases. Methods. This technical note with illustrative clinical cases describes practical aspects of transradial neurointervention, with emphasis on patient and access selection, vascular anatomy assessment, procedural planning, puncture techniques, catheter navigation, vasospasm prevention, equipment selection, hemostasis, and complication management. Case presentation. Four illustrative cases were selected to demonstrate the use of transradial approach as either a primary access route or a rescue strategy after technically difficult or unsuccessful transfemoral approach. The presented cases included carotid artery stenting for severe internal carotid artery stenosis, vertebral artery stenting, and endovascular embolization of a paraclinoid aneurysm. In three cases, transfemoral access was technically difficult or unsuccessful because of unfavorable vascular anatomy, including a type III aortic arch and aortoiliac occlusive disease, and transradial approach was subsequently used as an alternative access route. In one patient with obesity, transradial approach was selected as the primary access route because of the anticipated increased risk of femoral access-site complications. Conclusion. Transradial approach was technically feasible for completing the planned neurointerventional procedures in these four selected cases, both as a primary access strategy and as a rescue route after technically difficult or unsuccessful transfemoral approach. Careful patient selection, assessment of vascular anatomy, appropriate equipment selection, and familiarity with radial-specific techniques are important for successful implementation. Keywords: multifocal atherosclerosis, steno-occlusive carotid disease, сerebral angiography, neurointervention, endovascular neurosurgery, transradial access, transfemoral access.

Background: Chronic carotid artery occlusive disease is associated with a high risk of ischemic events and long-term neurological deficits. Optimising surgical revascularisation outcomes requires an integrated understanding of anatomical, hemodynamic, and functional factors. This study aims to assess the neuro-radiological, clinical, and cognitive outcomes following cerebral revascularisation in patients with chronic internal carotid artery occlusion. Methods: This single-centre, prospective, open-label interventional longitudinal study includes 60 patients with chronic internal carotid artery occlusion undergoing superficial temporal artery-to-middle cerebral artery (STA–MCA) bypass at National Centre for Neurosurgery in Kazakhstan. The primary endpoint of the study is the incidence of ischemic stroke during the 6-month follow-up period after surgery. Pre- and postoperative evaluations include detailed angiographic assessment of collateral circulation and donor vessel diameter, as well as cerebral perfusion imaging using arterial spin labelling MRI. Neurological and cognitive function are assessed using standardized clinical and neuropsychological tests. Early and six-month follow-up evaluations focus on bypass patency, perfusion changes, and clinical outcomes. Discussion: By integrating anatomical, hemodynamic, and functional data, this study aims to identify predictors of successful revascularisation and favorable clinical outcomes. Correlation of postoperative angiographic and perfusion findings with cognitive and neurological recovery may refine surgical decision-making, enhance risk stratification, and optimize individualized patient care. Ultimately, this comprehensive approach seeks to improve the overall efficacy and safety of STA-MCA bypass in patients with chronic carotid artery occlusive disease. Trial registration: ClinicalTrials.gov NCT07396025 . Registered on February 5, 2026.

Background: Moyamoya disease (MMD) is a progressive cerebrovascular disorder and an important cause of ischemic stroke in children. Surgical revascularization is the mainstay of treatment; however, data on functional and angiographic outcomes in pediatric populations, particularly from Central Asia, remain limited. Methods: We conducted a retrospective single-centre cohort study of 45 pediatric patients with MMD who underwent surgical revascularization between 2013 and 2025. Clinical outcomes were assessed using the modified Rankin Scale (mRS), and angiographic outcomes were evaluated using the Matsushima grading system. Associations between clinical, surgical, and radiological factors and functional outcomes were analysed. Results: The mean age at diagnosis was 9.5 ± 3.8 years, with a mean follow-up of 20.6 ± 17.5 months. Headache was the most common presenting symptom (77.8%), while ischemic stroke was the predominant cerebrovascular presentation, occurring in more than 70% of patients. More than 75% of patients had advanced angiographic disease (Suzuki stages IV–V). Functional outcomes improved significantly following surgery, with mean mRS decreasing from 2.09 ± 1.26 to 1.64 ± 1.00 (p = 0.004). At follow-up, 82.2% of patients achieved favorable outcomes (mRS 1–2). Bilateral revascularization was performed in 64.4% of cases. No significant differences were observed between direct, indirect, and combined techniques, although a trend toward improved outcomes with direct and combined approaches was noted. Postoperative collateral formation was strongly associated with functional outcome (p = 0.005). Conclusions: Surgical revascularization is associated with significant functional improvement and low recurrence rates in pediatric MMD. The quality of collateral formation, rather than the surgical technique itself, appears to be the primary determinant of outcome.

Twiddler’s syndrome is an uncommon complication of deep brain stimulation, arising from the inadvertent rotation of the implanted pulse generator, which results in lead coiling, displacement, or fracture. This results in stimulation failure and symptom recurrence, often necessitating surgical revision. While well-documented in cardiac devices, Twiddler’s syndrome remains infrequent in operations. Early diagnosis through radiographic imaging and impedance abnormalities is crucial for prompt intervention. We report two cases of Twiddler’s syndrome in patients with movement disorders: a 73-year-old male with Parkinson’s disease and a 55-year-old female with multifocal dystonia, both of whom had bilateral deep brain stimulation with left-sided dual-channel implanted pulse generator. After years of effective symptom control, both patients presented with worsening motor symptoms. Device examination revealed abnormal impedance readings, and imaging confirmed extensive lead coiling. Surgical revision was performed, including lead replacement and implanted pulse generator repositioning under the pectoralis fascia. Both patients demonstrated significant symptom improvement postoperatively, with restored impedance levels and functional recovery. Twiddler’s syndrome is a rare but critical complication of deep brain stimulation, leading to hardware failure and clinical deterioration. Early diagnosis through imaging and impedance monitoring is essential. Preventive strategies, including secure implanted pulse generator fixation and careful pocket sizing, are key to minimizing risk and improving patient outcomes.

Background: Deep brain stimulation (DBS) is an effective treatment for movement disorders, but its long-term efficacy may be undermined by hardware complications such as lead fractures. These complications increase healthcare costs and necessitate surgical revisions. The frequency, timing, and clinical factors associated with lead fractures remain poorly understood. Objective: This study aimed to determine the incidence, timing, and clinical factors associated with lead fractures in a large cohort of DBS patients over a 10-year period. Methods: This retrospective study analyzed data from 325 patients who underwent bilateral DBS implantation at the National Centre for Neurosurgery from 2013 to 2023. The analysis specifically focused on 17 patients who experienced lead fractures during the long-term follow-up period. Results: Among the 325 patients, lead fractures were identified in 17 patients (5.23%), affecting 18 electrodes. The majority of cases involved patients with Parkinson’s disease (76.5%) or dystonia (23.5%), with an average age of 59.17 ± 8.77 years. Nearly all patients with lead fractures had a history of trauma. Additionally, two cases were associated with active engagement in sports, particularly activities involving movements like pulling up on a horizontal bar, while Twiddler’s Syndrome was identified in two other cases. All electrode fractures required surgical revision. Conclusions: Lead fractures, while rare, remain a significant complication in DBS systems. Precise surgical techniques, early detection, and advancements in DBS hardware design may help to mitigate this risk. Future innovations, such as durable leads or wireless systems, may improve long-term outcomes in DBS therapy for movement disorders.