Neurointerventional Radiology for the Aspiring Radiology Resident: Current State of the Field and Future Directions

Endovascular arterial embolization versus conservative management with nasal packing alone for severe epistaxis: a nationwide cohort study

BACKGROUND

Endovascular arterial embolization (EAE) is an effective treatment for severe epistaxis refractory to conservative management with nasal packing. However, contemporary real-world data are lacking, as are data on head-to-head comparisons of EAE versus nasal packing alone.

METHODS

This was a retrospective cohort study of the Nationwide Readmissions Database (NRD) from 2016 to 2021 in the United States. Patients with severe epistaxis treated with nasal packing alone or EAE with or without nasal packing were included and followed for 180 days. Propensity score matching (PSM) for demographics, comorbidities, and hemorrhage risk factors was performed to balance patient characteristics. Primary outcome was recurrent epistaxis. Secondary outcomes include rates of non-routine hospital discharge (indicating short-term morbidity or mortality) and ischemic stroke.

RESULTS

25 160 patients admitted to hospital for severe epistaxis were included; 754 (3.3%) underwent EAE. After PSM, 1542 patients remained in the conservative management group, and 743 remained in the EAE group. Overall, the risk of epistaxis readmission was lower after EAE compared with conservative management (HR 0.47, 95% CI 0.26 to 0.87, P=0.016); the 180-day epistaxis readmission rate was 4.6% and 10.6%, respectively (P=0.024). EAE was significantly associated with lower rates of non-routine discharge (22.1% vs 28.9%, P=0.026), despite a higher rate of ischemic stroke (1.6% vs 0.4%, P=0.017).

CONCLUSIONS

For patients with severe epistaxis, EAE is associated with a significant reduction of epistaxis recurrence rates as well as lower rates of patient morbidity compared with nasal packing alone, despite a small but significant increase in risk of ischemic stroke.

Safety and effectiveness of vascular closure devices in interventional radiological procedures

BACKGROUND

Although it is well known that vascular closure devices (VCD) are commonly used in therapeutic interventional radiological procedures, standard use in diagnostic procedures is not as well studied.

PURPOSE

The aim of this study was to determine the real-world safety and effectiveness of the VCD in both diagnostic and therapeutic interventional radiological procedures.

MATERIALS AND METHODS

A retrospective, single center study included all patients where VCDs were used for either a diagnostic or therapeutic interventional procedure. Various demographic and clinical risk factors were recorded and examined for any significant association with successful deployment and complications.

RESULTS

A total of 2072 patients were included. VCDs were successfully deployed in 95.2% of the patients with 4.8% of perioperative complications, which included minor oozing from the puncture site, small hematoma less than or equal to 5 cm, large hematoma greater than 5 cm, pain, and loss of vascular access. Therapeutic (vascular interventional radiology (VIR) and neuro-interventional radiology (NIR)) procedures (OR 3.03, 95% CI 1.51-6.09, p = 0.002), use of Angioseal (OR 5.26, 95% CI 3.13-8.33), p < 0.001), and no use of antiplatelet medications (OR 0.47, 95% CI 0.22-0.97, p = 0.041) were independently associated with successful deployment of VCDs when controlled for other risk factors. Smoking (OR 3.50, 95% CI 2.00-6.05, p = <0.001), use of antiplatelet (OR 2.01, 95% CI 1.04-3.87, p = 0.037) and use of heparin (OR 1.78, 95% CI 1.10-2.86, p = 0.018) were independently associated with higher complication rates.

CONCLUSION

VCD's were successfully deployed in 95.2% of the patients with 4.8% of perioperative minor complications.

Neurointerventional Radiology: History, Present and Future

Neurointerventional Radiology (NIR), encompassing neuroendovascular surgery, endovascular neurosurgery, and interventional neurology, is an innovative and rapidly evolving multidisciplinary specialty focused on minimally invasive therapies for a wide range of neurological disorders. This review provides a comprehensive overview of NIR, discussing the three routes into the field, highlighting their distinct training paradigms, and emphasizing the importance of unified approaches through organizations like the Society of Neurointerventional Surgery (SNIS). The paper explores the benefits of co-managed care and its potential to improve patient outcomes, as well as the role of interdisciplinary collaboration and cross-disciplinary integration in advancing the field. We discuss the various contributions of neurosurgery, radiology, and neurology to cerebrovascular surgery, aiming to inform and educate those interested in pursuing a career in neurointervention. Additionally, the review examines the adoption of innovative technologies such as robotic-assisted techniques and artificial intelligence in NIR, and their implications for patient care and the future of the specialty. By presenting a comprehensive analysis of the field of neurointervention, we hope to inspire those considering a career in this exciting and rapidly advancing specialty, and underscore the importance of interdisciplinary collaboration in shaping its future.

Recent trends in high-volume Medicare stroke thrombectomy provider characteristics

BACKGROUND

Intracranial mechanical thrombectomy (MT) is increasingly indicated for use in acute ischemic stroke patients. We analyzed recent trends in the characteristics and geographic distributions of physicians providing this service with frequency to Medicare beneficiaries.

METHODS

We linked public data sources to elucidate and visualize trends in high-volume MT providers between 2016 and 2019.

RESULTS

High-volume MT providers increased by 184% between 2016 and 2019. The number of neurosurgeons, neurologists, and radiologists in this physician population increased by 251%, 205%, and 139%, respectively. Male practitioners accounted for 96% of providers in the most recent year of analysis. International medical graduates accounted for roughly one-third of these physicians across all 4 years of analysis. As of 2019, the three states with the most high-volume MT providers were Florida, California, and Texas, accounting for 7%, 7%, and 6% of providers, respectively.

CONCLUSIONS

High-volume providers of MT services for Medicare beneficiaries represent a dynamic and rapidly expanding subset of physicians with diverse specialty backgrounds.

Comparison of Application Effects of Different Hemostasis Methods After Ischemic Cerebrovascular Intervention

Objective

To explore the effects of two different hemostasis methods, namely, arterial compression devices and vascular closure devices, in the ischemic cerebrovascular intervention to provide a theoretical basis for clinical selection of hemostasis methods.

Methods

A total of 302 patients who underwent ischemic cerebrovascular intervention in our hospital from January 2016 to December 2020 were selected as the research subjects and randomly divided into the control group (n = 151) and the observation group (n = 151). The patients in both groups underwent cerebrovascular intervention. The patients in the control group were treated with an artery compressor for hemostasis after the operation, while those in the observation group were treated with vascular closure devices for hemostasis. The hemostatic indexes and vascular parameters at the puncture site before and after the operation were compared between the two groups. The comfort level of the patients was assessed at 6, 12, and 24 h after the operation with the Kolcaba Comfort Scale score, and the postoperative complications were recorded.

Results

There was no significant difference in the success rate of hemostasis between the two groups (p > 0.05). The hemostatic time and immobilization time of (2.69 ± 0.62) min and (4.82 ± 0.93) h in the observation group were lower than those in the control group with (16.24 ± 3.58) min and (7.94 ± 1.86) h (p < 0.05). The differences in the minimum inner diameter of the puncture site and its nearby vessels and the peak velocity of blood flow between the two groups before and after the operation were not statistically significant within or between groups (p > 0.05). The scores of the Kolcaba comfort scale in the observation group (80.16 ± 8.49) and (93.65 ± 9.26) at 6 and 12 h, respectively, after the operation, were higher than those in the control groups (72.08 ± 7.54) and (85.49 ± 8.63) (p < 0.05). The 24 h postoperative Kolcaba comfort scale score was (97.54 ± 9.86) in the observation group and (96.82 ± 9.64) in the control group, and the difference was not statistically significant (p > 0.05). In the control group, there were 7 cases of dysuria, 12 cases of low back pain, 14 cases of sleep disorder, 20 cases of mental stress, and 5 cases of wound bleeding, and the total incidence of complications was 38.41% (58/151). In the observation group, there were 4 cases of dysuria, 8 cases of low back pain, 10 cases of sleep disorder, 14 cases of mental stress, and 3 cases of wound bleeding, and the total incidence of complications was 25.83% (39/151). The total incidence of complications in the observation group was lower than that in the control group (p < 0.05).

Conclusion

For patients with ischemic cerebrovascular disease undergoing femoral artery puncture intervention, the use of vascular closure devices can stop the bleeding quickly, which can significantly shorten the bleeding time, and the postoperative braking time of patients is short, with high comfort and fewer complications.

A Multifaceted Approach to Optimizing AAV Delivery to the Brain for the Treatment of Neurodegenerative Diseases

Despite major advancements in gene therapy technologies, there are no approved gene therapies for diseases which predominantly effect the brain. Adeno-associated virus (AAV) vectors have emerged as the most effective delivery vector for gene therapy owing to their simplicity, wide spread transduction and low immunogenicity. Unfortunately, the blood-brain barrier (BBB) makes IV delivery of AAVs, to the brain highly inefficient. At IV doses capable of widespread expression in the brain, there is a significant risk of severe immune-mediated toxicity. Direct intracerebral injection of vectors is being attempted. However, this method is invasive, and only provides localized delivery for diseases known to afflict the brain globally. More advanced methods for AAV delivery will likely be required for safe and effective gene therapy to the brain. Each step in AAV delivery, including delivery route, BBB transduction, cellular tropism and transgene expression provide opportunities for innovative solutions to optimize delivery efficiency. Intra-arterial delivery with mannitol, focused ultrasound, optimized AAV capsid evolution with machine learning algorithms, synthetic promotors are all examples of advanced strategies which have been developed in pre-clinical models, yet none are being investigated in clinical trials. This manuscript seeks to review these technological advancements, and others, to improve AAV delivery to the brain, and to propose novel strategies to build upon this research. Ultimately, it is hoped that the optimization of AAV delivery will allow for the human translation of many gene therapies for neurodegenerative and other neurologic diseases.

Vascular imaging of the spine in the US Medicare population: Catheter and MR angiography volumes from 2004 to 2016

AIMS

The purpose of our study was to analyze utilization trends and physician specialty distribution in spinal catheter angiography and magnetic resonance angiography in the Medicare fee-for-service population.

METHODS

Data from the CMS Physician/Supplier Procedure Summary Master Files for 2004 to 2016 were used for this study. The Current Procedural Terminology version 4 codes for spinal magnetic resonance angiography (72159) and spinal catheter angiography (75705) were used to analyze the volumes of these procedures. Using Medicare's 108 specialty code, we compared procedure volumes among physician specialties. Data analysis was performed using SAS version 9.3 for Windows.

RESULTS

The volume of spinal catheter angiography performed was 4758 in 2004, peaked at 6869 in 2012, and dropped to 6656 in 2016. Overall, the volume of spinal catheter angiography increased by 40% from 2004 to 2016. Radiologists performed the majority of these procedures (3736 or 56.1%) in 2016, followed by neurosurgeons (2456 or 36.9%), and neurologists (346 or 5.2%). The spinal magnetic resonance angiography volume fluctuated between 0 and 1 from 2004 to 2009, then precipitously increased to 40 in 2010, peaked at 133 in 2011, and declined to 81 in 2016. The volume of spinal magnetic resonance angiography procedures increased by 8000% from 2004 to 2016, with radiologists performing the majority of them.

CONCLUSION

Our results show that spinal catheter angiography volumes continue to rise in the Medicare fee-for-service population, and are largely performed by radiologists, neurosurgeons, and neurologists. Although spinal magnetic resonance angiography volumes have started to increase, they comprise only a small fraction of studies performed for vascular evaluation of the spine.