Twenty-first century innovations in neuroradiology treatments

Table 1 Comparison of endovascular stents

Feature	Early-generation/bare-metal stents	Drug-eluting stents	Modern stents (micromesh/balloon-expandable)
Design	Large cell openings, rigid, limited conformability	Drug-eluting stents	Micron-sized pores (micromesh); high radial force (balloon-expandable)
Mechanism	Mechanical scaffolding	Reduces neointimal hyperplasia	Prevents plaque protrusion; traps debris; improves vessel expansion
Key outcomes	Associated with restenosis and increased stroke risk	Lower rates of in-stent restenosis and stroke recurrence	Lower residual stenosis and fewer complications (vs single-layer stents)
Complications	Endothelial injury; restenosis		Stroke/TIA risk varies depending on the comparison (vs self-expanding stents or medical therapy)
Evidence comparison		Better outcomes than bare-metal stents	Qureshi: Improved outcomes vs self-expanding stents; Zaidat: Worse outcomes vs medical therapy
Cost consideration			Higher cost than medical therapy; more favorable in ≥ 70% stenosis

TIA: Transient ischemic attacks.

Table 2 Comparison of endovascular techniques

Feature	Microsurgical resection	Early embolic agents (n-BCA)	Modern embolic agents (Onyx, PHIL)
Role	Gold standard for select patients	Adjunct to surgery; can be definitive in select cases	Adjunct or definitive therapy in select cases
Invasiveness	Open surgery	Minimally invasive	Minimally invasive
Mechanism	Direct removal of AVM nidus	Rapid polymerization upon contact with blood	Slow solidification allowing controlled injection and deeper penetration
Effectiveness	High obliteration rates (> 98%)	Used to reduce nidus size and delineate feeders	Higher occlusion rates and reduced need for surgery
Injection control		Difficult due to rapid polymerization	Improved control with prolonged injection
Safety concerns	Limited in deep/complex AVMs; hemorrhagic risk	Catheter entrapment, vessel occlusion	Improved control; safer delivery profile
Technological features		Adhesive embolic agent	Non-adhesive agents with deeper nidus penetration
Microcatheter considerations		Risk of entrapment with early systems	Detachable-tip microcatheters improve safety
Limitations	Limited in deep-seated or complex AVMs	Poor injection control and higher complication risk	Risk of premature tip detachment

nBCA: N-butyl cyanoacrylate; PHIL: Precipitating hydrophobic injectable liquid; AVM: Arteriovenous malformation.

Table 3 Minimally invasive spine interventions

Feature	Epidural steroid injection	Percutaneous discectomy	Spinal ablation (adjunct)
Mechanism	Corticosteroid injection into epidural space to reduce inflammation	Removal of herniated disc material using image-guided instruments	Ablation of sinuvertebral nerve
Technique	C-arm fluoroscopy; transforaminal approach	Image-guided; endoscopic visualization	Performed in combination with discectomy
Anesthesia	Not specified	No general anesthesia required	Not specified
Clinical outcomes	Improvement in PROMIS pain interference scores at 3, 6, and 12 months	Reduced blood loss, shorter hospitalization, smaller incisions, lower inflammatory markers vs open discectomy	Lower pain and disability scores when combined with discectomy vs discectomy alone
Additional notes	Used in patients with cervical radicular pain refractory to conservative therapy	Compared with open discectomy	Adjunctive therapy

PROMIS: Patient-Reported Outcomes Measurement Information System.

Table 4 Key innovations in 21^st-century neuroradiology and their clinical applications and outcomes

Advances in specific areas	Advancements details	Outcomes
Management of cerebrovascular accidents
Stoke triage and imaging analysis	Enables timely and accurate patient evaluation, AI-enabled technology can help reduce prehospital delays, and can rapidly detect large vessel occlusions	Wrist-worn accelerometers integrated with AI algorithms detected stroke as short as 15 mins after onset with accuracy from 0.893 to 0.947[8]. Rapid CTA correctly identified 93% occlusions with a 0.94 sensitivity and NPV of 0.98[10]
Mechanical thrombectomy for acute ischemic stroke	Associated with higher rates of reperfusion, faster neurological improvement, superior functional outcomes	> 90% reperfusion: 89% of patients who underwent mechanical thrombectomy achieve successful reperfusion (> 90% reperfusion) compared to those who underwent alteplase alone (89% vs 34%, P < 0.001)[14]. Median days spent at home within 90 days of discharge were 73 (mechanical thrombectomy) vs 15 (alteplase alone); P = 0.001[14]. Mechanical thrombectomy showed a median gain of 9.3 disability- adjusted life years vs 4.9 in control group receiving alteplase alone[14]
Intracranial-endovascular techniques
Endovascular stenting for intracranial atherosclerotic disease	Prevents plaque protrusion, and reduces rates of major adverse events	“Patients who had carotid stenting procedure using a single-layer carotid stent had statistically significantly more periprocedural neurological complications 8.3% (n = 35) than the double-mesh stent group 2% (n = 3), mostly due to more transient ischemic attacks in the single-layer stent group 4% (n = 17) compared to the double-mesh group 0.7% (n = 1)”[20]
Endovascular aneurysm treatment	Alters aneurysmal hemodynamics to promote progressive occlusion and parent vessel remodeling minimally invasively	Complete occlusion in 55.1% of aneurysm treated with stent assisted coiling (28% recurrence rate) vs 86.7% of aneurysms treated with flow diverters (2.2% recurrence rate)[27]
Endovascular treatment of arteriovenous malformations	Refined microcatheters and newer embolic agents improve safety and efficacy of endovascular treatment	Embolization with Onyx leads to less surgery than embolization with n-BCA (P = 0.0015)[31]
Neurovascular robotics and remote intervention	Can help overcome geographic barriers and expedite stroke treatment	Remote clinicians were able to successfully navigate catheters and guidewires from femoral artery to middle cerebral artery within 15 minutes[36]
Management of brain tumors
Minimally invasive tumor ablation	Suited for small lesions that are difficult to access surgically and help preserve surrounding healthy tissue	Median survival in patients with recurrent glioblastoma increased from 90-150 days to 361 days following LITT[39]
Brain tumor segmentation and treatment planning	Can detect small lesions that could have been overlooked and reduce the risk of overtreatment	A three-dimensional U-Net convolutional neural network for detecting brain lesions on 18F-FET PET imaging achieved an accuracy of 0.9868 during training and 0.9856 during validation, with 100% sensitivity and specificity and no false positives[44]
Advanced perfusion and functional imaging integration	Enables precise localization and preserves eloquent cortex	High-grade gliomas had rCBF of 3.32 ± 1.87 and low-grade gliomas had rCBF of 1.16 ± 0.38. Knowing the CBF can allow precise localization and guide surgeons in resection[49]
Spine interventions
Spine cement augmentation	Percutaneous injection of PMMA under imaging guidance can relieve pain due to osteoporosis	68% of 38 patients with 70 osteoporotic fractures who underwent vertebroplasty experienced complete pain relief within 48 hours[55]. Kyphoplasty showed increased pain reduction vs conservative treatment at 1 month (MD: 2.32, -3.65 to -0.99, P < 0.001)[56]
Minimally invasive spine interventions	Improves targeting accuracy and is associated with reduced blood loss	Patients with cervical radiculopathy who had a transforaminal epidural steroid injection had PROMIS PI at 3-, 6-, and 12-months follow-up that statistically improved by 2.2 (95%CI: 2.1-2.4, P = 0.02), 2.3 (95%CI: 2.1-2.5, P = 0.03), and 2.7 (95%CI: 2.5-3.0, P = 0.03) points, respectively[58]
Image-guided therapeutic strategies in neurological disorders
Focused ultrasound for essential tremor and Parkinson’s	Noninvasive and can assess effects during treatment to monitor ablation	Decreased essential tremor severity from a mean baseline score of 20.4 to 4.3 at three months and 5.2 at twelve months[62]. Unified Parkinson’s Disease Rating Scale scores decreasing from 37.4 to 18.8 one week after treatment[63]
Image-guided gene and cellular therapies	Enables precise visualization of drug delivery and is a potential treatment for neurodegenerative diseases	In a study where three cohorts with Parkinson’s disease received VY-AADC01 gene therapy delivered to the putamen under MRI guidance with doses of ≤ 7.5 × 1011, ≤ 1.5 × 1012, and ≤ 4.7 × 1012 vector genomes, with corresponding putaminal coverage of 21%, 34%, and 42%, PET imaging demonstrated dose-dependent increases in L-amino acid decarboxylase expression (13%, 56%, and 79%), along with reduced antiparkinsonian medication use at six months and improved clinical outcomes and quality of life at twelve months[66]
Radiomics and predictive analytics in neuroradiology	Reveal patterns imperceptible to the naked eye and allows clinicians to anticipate symptom recurrence	In a study evaluating radiomics combined with machine learning to predict the response of metastatic brain tumors to Gamma Knife radiosurgery, the radiomics-based model achieved accuracies of 78% and 87% and sensitivities of 78% and 87%, respectively, compared with 44% and 54% for visual assessment alone[24]

AI: Artificial intelligence; NPV: Negative predictive value; CAT: Computer tomography angiography; CBF: Cerebral blood flow; PROMIS-PI: Patient-Reported Outcomes Measurement Information System-pain interference; LITT: Laser interstitial thermal therapy; n-BCA: N-butyl cyanoacrylate; FET PET: Fluoro-ethyl-L-tyrosine positron emission tomography.