AJNR. American journal of neuroradiology最新文献

Vertebrogenic pain due to degenerated or damaged vertebral endplates is a significant source of chronic low back pain.¹ The pathogenesis of vertebrogenic pain is attributed to the presence of endplates nociceptors that transmit afferent signals to the basivertebral nerve (BVN), located posteriorly within the vertebral body.^2,3 Chronic endplate inflammation triggers nociceptor proliferation, and associated chemical sensitization and mechanical stimulation leads to pain signals transmitted via the BVN and perceived as low back pain.^1,2 Therefore, radiofrequency ablation of the BVN has emerged as a potential minimally-invasive technique for management of vertebrogenic low back pain.^4,5 The thermal damage induced adjacent to the conducting region of the radiofrequency probe leads to interruption of pain transmission from vertebral endplates.^5,6 This video article gives an overview of the indications, procedural considerations, technical approach of basivertebral nerve ablation (BVNA), as well as post-procedure care and patient outcomes with representative clinical images obtained from our experience.

Vertebrogenic pain due to degenerated or damaged vertebral endplates is a significant source of chronic low back pain.¹ The pathogenesis of vertebrogenic pain is attributed to the presence of endplates nociceptors that transmit afferent signals to the basivertebral nerve (BVN), located posteriorly within the vertebral body.^2,3 Chronic endplate inflammation triggers nociceptor proliferation, and associated chemical sensitization and mechanical stimulation leads to pain signals transmitted via the BVN and perceived as low back pain.^1,2 Therefore, radiofrequency ablation of the BVN has emerged as a potential minimally-invasive technique for management of vertebrogenic low back pain.^4,5 The thermal damage induced adjacent to the conducting region of the radiofrequency probe leads to interruption of pain transmission from vertebral endplates.^5,6 This video article gives an overview of the indications, procedural considerations, technical approach of basivertebral nerve ablation (BVNA), as well as post-procedure care and patient outcomes with representative clinical images obtained from our experience.

Background: To analyze the imaging features of the lateral rectus-superior rectus (LR-SR) band as imaged with magnetic resonance imaging (MRI) at different orbital scan locations.

Methods: The LR-SR band features of patients who underwent high-resolution MRI for non-orbital pathology were evaluated at pre-defined locations by two independent readers. Analyzed features included (1) visibility, (2) continuity, and (3) superotemporal bowing of LR-SR band in a binary manner at 2.5 mm anterior (Zone I), at (Zone II) and posterior (Zone III) to the globe-optic nerve junction.

Results: Forty-eight orbits of 26 patients with an age range of 58-86 years were included. Visualization of the LR-SR band was significantly higher in Zone I (89.6%) compared to Zone II (79.2%) (p=0.03) and to Zone III (47.9%) (p<0.001). Among the orbits in which the LR-SR band was visualized, band continuity was most frequently observed in Zone I (94.7%), compared to Zone II (68.4%) (p=0.002) and in Zone III (52.2%) (p<0.001). Superotemporal bowing was detected with higher frequency posteriorly, rising from 21.1% in Zone I to 47.4% in Zone II (p=0.002) and to 56.5% in Zone III (p<0.001). A higher degree of reproducibility for LR-SR band visibility and continuity was noted in anterior scan locations.

Conclusions: The LR-SR band is most consistently visualized on coronal MRI images obtained anterior to the globe-optic nerve junction, while degenerative changes are more frequently observed in posterior scan locations. Establishing and reporting a standardized coronal imaging plane referenced to a consistent anatomic landmark may improve reproducibility and comparability of the LR-SR band across studies and allow for more robust clinical interpretation.

Background and purpose: The labyrinth is a complex anatomic structure in the temporal bone. However, high-resolution imaging of its membranous portion is challenging because of its small size and the limitations of current MRI techniques. Deep learning reconstruction (DLR) represents a promising approach to advancing MR image quality, enabling higher spatial resolution and reduced noise. This study aims to evaluate DLR high-resolution 3D heavy T2-weighted TSE (3D-T2) MRI sequences for visualizing the labyrinthine structures, comparing them with conventional 3D-T2 sequences. The goal is to improve spatial resolution without prolonging acquisition times, allowing a more detailed view of the labyrinthine microanatomy.

Materials and methods: High-resolution heavy T2-weighted TSE SPACE images were acquired in patients by using 3D-T2 and improved T2 weighted turbo spin-echo sequence incorporating deep learning reconstruction (DLR-3D-T2). Two radiologists rated structure visibility on a 4-point qualitative scale for the spiral lamina, scala tympani, scala vestibuli, scala media, utricle, saccule, utricular and saccular maculae, membranous semicircular ducts, and ampullary nerves. Ex vivo 9.4T MRI served as an anatomic reference.

Results: DLR-3D-T2 significantly improved the visibility of several inner ear structures. The utricle and utricular macula were systematically visualized, achieving grades ≥3 in 95% of cases (P < .001), while the saccule remained challenging to assess, with grades ≥3 in only 10% of cases. The cochlear spiral lamina and scala tympani were better delineated in the first 2 turns but remained poorly visible in the apical turn. Semicircular ducts were only partially visualized, with grades ≥3 in 12.5% to 20% of cases, likely due to resolution limitations relative to their diameter. Ampullary nerves were moderately improved, with grades ≥3 in 52.5% to 55% of cases, depending on the nerve.

Conclusions: While DLR does not yet provide a complete anatomic assessment, it represents a important step forward in the noninvasive evaluation of inner ear structures. Pending further technical refinements, this approach may help reduce reliance on delayed gadolinium-enhanced techniques for imaging membranous structures.

This study assessed national trends and geographic distribution of neuroradiology fellowship positions in the United States from 2009 to 2025. ACGME-accredited programs increased from 86 to 94 (+9%), with number of active fellows in training rising from 250 to 262 (+5%). NRMP positions grew from 190 to 316 (+66%), and fill rates improved from 67% to 91%. IMGs increased from 18.8% to 27.1%, while U.S. MD representation declined slightly. In 2025, 94 programs across 33 states and D.C. offered 385 positions; 11 states had none. Despite national growth, programs remain concentrated, with California, New York, and Massachusetts hosting over one-quarter of all positions. Awareness of the pipeline and its correlation with the market demand for subspecialist neuroradiologists is important for policy planning and addressing workforce needs to preserve patient access to care.

Purpose: To evaluate the feasibility and technical performance of integrating a Delay Alternating with Nutation for Tailored Excitation (DANTE) preparation into a deep learning-accelerated, post-contrast T1-SPACE sequence for intracranial vessel wall imaging (IC-VWI).

Materials and methods: In this retrospective, single-center study, 35 patients (22 women; mean age, 57.9 ± 17.1 years) underwent IC-VWI using post-contrast DL-T1-SPACE with (T1-SPACE_DL+DANTE) and without (T1-SPACE_DL) a DANTE preparation. Two neuroradiologists independently scored lumen and wall visualization across the arterial segments on a 4-point Likert scale (1: worst to 4: best) and graded venous flow artifacts along the middle cerebral artery (MCA), peri-mesencephalic veins (PMV), deep cerebral veins (DCV), and cortical veins (CV). Intersequence comparisons used cumulative-link mixed-effects models (CLMMs); segments were additionally pooled and analyzed as proximal versus distal. Venous flow artifact scores were compared with paired Wilcoxon tests between sequences and percentage agreement between readers. Exploratory Bland-Altman analysis was also performed for both readers.

Results: A total of 556 vessel-segment pairs were analyzed. In CLMM analysis, T1-SPACE_DL+DANTE improved lumen scores versus T1-SPACE_DL (pooled OR 40.02; 95% CI 24.06-66.57; FDR p<0.001) but reduced wall scores (pooled OR 0.11; 95% CI 0.08-0.14; FDR p<0.001). By anatomic group, lumen ORs were 26.03 (proximal) and 91.93 (distal), and wall ORs were 0.12 (proximal) and 0.04 (distal) (all FDR p<0.001). Venous flow artifacts improved across all analyzed subsites (p<0.001). ±1-point inter-reader concordance was near perfect across analyses. Bland-Altman plots showed negative lumen bias (favoring T1-SPACE_DL+DANTE) and positive wall bias (favoring T1-SPACE_DL) without consistent proportional bias.

Conclusion: Adding DANTE preparation to deep-learning accelerated IC-VWI was associated with fewer flow-related artifacts and a clearer depiction of the vessel lumen, which may support a more accurate assessment of intracranial vasculopathies and aneurysms. Potential gains were accompanied by a modest wall-visualization penalty, which is not unexpected with a flow-suppression pulse.

Skull base biopsies are technically challenging due to complex anatomy and proximity to vital structures. Traditional transcervical and transoral approaches offer limited access to the clivus and risk poor depth perception and complications. Although transnasal techniques have improved access, X-ray-guided methods are rarely reported. We describe the first transnasal X-ray-guided clival biopsy in a middle-aged patient with suspected skull base osteomyelitis. Preoperative CT, MRI, and PET-CT enabled precise targeting and safe trajectory planning. In a biplane angiographic suite, a guidewire was advanced transnasally, and a 9F introducer sheath was positioned against the anterior clivus. An 11G bone needle was then advanced under fluoroscopy and cone-beam CT into the lesion. Tissue sampling was successful and complication-free, confirming Staphylococcus haemolyticus osteomyelitis, which resolved with targeted antibiotics. This minimally invasive technique offers accurate access to superior clival lesions and may broaden options for selected skull base biopsy cases.

Background and purpose: T1-weighted hypointense lesions resulting from MS reflect chronic, irreversible tissue injury mediated by autoimmune inflammation and are associated with neurologic disability. The evolution of such lesions is heterogeneous in the presence or absence of disease-modifying therapy (DMT). We investigated dynamic changes of T1-weighted hypointense lesions along with total T1-weighted hypointense lesion volumes to further understand MRI features that may reflect clinically silent disease activity.

Materials and methods: A retrospective study was performed involving people with MS with 3 consecutive standardized MRI time points within a single academic center. Individuals with formal neuroradiology interpretations lacking evidence of T1-weighted hypointense lesion change were included. Approximately 8-12 nongadolinium-enhancing T1-weighted hypointense lesions measuring at least 3 mm² were selected from a 3D MPRAGE from each individual. Total T1-weighted hypointense lesion volumes were also quantified at each time point. The Lambda, Mu, and Sigma method was used to estimate the SD of the annualized volume rate of change as a function of the lesion volume at the prior time point. The longitudinal associations between treatment class on T1-weighted hypointense lesion dynamics and relationship to patient- or physician-reported disease worsening, acute clinical relapse, and MRI advancement were evaluated.

Results: The cohort comprised 91 people (71.4% women; mean disease duration of 9.32 years; SD: 7.22 years) who were primarily white (80.2%). Of treated individuals, most were exposed to non-high-efficacy DMTs at least once (48.4%). In total, 273 MRI studies yielding 790 T1-weighted hypointensities were studied longitudinally. Predominantly enlarging T1-weighted hypointense lesions were seen in 82.4% of individuals over 3 MRI time points. The odds of overall T1-weighted lesion volume contraction did not differ between those on high-efficacy treatment (P = .71) or those untreated (P = .85), compared with non-high-efficacy agents. Treatment group did not influence total change in T1-weighted hypointense lesion volumes, and correlations with clinical or MRI outcomes were not observed.

Conclusions: Current DMT classifications may have minimal influence on T1-weighted hypointense outcomes, highlighting the need for treatments that directly target ongoing tissue injury.

Background and purpose: Stent-assisted coiling (SAC) is widely used for the treatment of wide-neck, unruptured intracranial aneurysms. However, direct comparative data between different stent platforms remain limited. This study aimed to evaluate the safety and efficacy of the Low-profile Visualized Intraluminal Support (LVIS) stent versus the Neuroform Atlas stent in the treatment of unruptured ICA aneurysms measuring <10 mm in diameter.

Materials and methods: A retrospective analysis was performed on 287 unruptured ICA aneurysms (<10 mm) in 247 patients treated with SAC using either the LVIS or Neuroform Atlas stent across 3 affiliated institutions between March 2017 and December 2023. Patients were divided into 2 groups: group A (Neuroform Atlas) and group L (LVIS). After 1:1 propensity score matching for demographic, clinical, anatomic, and procedural variables, key outcomes including Raymond class 1 occlusion, volume embolization ratio, and periprocedural complications were compared between the 2 groups.

Results: Among the 287 aneurysms, 237 (82.6%) were treated with the Neuroform Atlas stent and 50 (17.4%) with the LVIS stent. Propensity score matching yielded 46 matched pairs. Immediately after treatment, group L demonstrated significantly higher rates of complete occlusion and a greater volume embolization ratio compared with group A (P = .022 and .004, respectively). At the 1-year follow-up, the complete occlusion rate remained significantly higher in group L than in group A (52% versus 24%; P = .007). The incidence of ischemic and hemorrhagic complications did not differ significantly between the 2 groups.

Conclusions: For unruptured ICA aneurysms <10 mm in diameter, SAC using the LVIS stent was associated with a significantly higher rate of complete occlusion at 1 year compared with the Neuroform Atlas stent, without an increase in periprocedural complications. These results support the safety and efficacy of the LVIS stent in achieving favorable long-term angiographic outcomes in small- to medium-sized unruptured ICA aneurysms.