AJNR. American journal of neuroradiology最新文献

Background and purpose: In multiple sclerosis, the choroid plexus is thought to promote and sustain the disease immunopathologic inflammatory process. However, its association with cortical pathology and disease progression is still uncertain. We aimed to characterize choroid plexus enlargement and evolution in MS and its relationship with imaging markers of compartmentalized inflammation and clinical outcome.

Materials and methods: One hundred patients with MS (74 relapsing-remitting [RRMS]; 26 secondary-progressive MS [SPMS] and 41 matched healthy controls (HC) underwent 3T MRI to measure brain volumes and 7T MRI for cortical and WM lesions, including paramagnetic rim lesion (PRL) segmentation. Choroid plexus volumes of the lateral ventricles were manually edited from FreeSurfer segmentation by 1 neurologist and normalized by total intracranial volume to estimate the choroid plexus ratio (CPR). The Expanded Disability Status Scale was assessed at baseline and longitudinally in 71 patients, 43 of whom had a follow-up MRI at 1.5 years. An extreme gradient boosting algorithm estimated the importance of CPR, alongside other imaging markers, in predicting disease phenotype (RRMS versus SPMS) and progression independent of relapse activity.

Results: Relative to HC, CPR was higher in patients (11.66 [3.21] versus 14.98 [4.37] × 10^-4, P = .001), both in RRMS and SPMS (P = .007, P = .003), and there was a mean ∼4% increase per year in CPR at follow-up, though it was not significant[ (P = .14). Choroid plexus enlargement correlated with greater PRL and cortical lesion volumes (r = 0.35, P < .001). CPR did not discriminate MS phenotype but predicted progression independent of relapse activity alongside CSF subarachnoid space volume, PRL, and cortical lesion volumes (median [median absolute deviation] area under the curve 0.71 [0.12], accuracy 0.74 [0.10], sensitivity 0.81 [0.12], and specificity of 0.52 [0.22]).

Conclusions: In MS, a CPR increase relates to imaging markers of compartmentalized disease activity including cortical lesions and PRLs and is a critical predictor of disease progression. Our findings could provide the rationale for implementing CPR estimation for prognosis prediction in MS.

Background and purpose: Viable malignant disease is uncommon in patients with persistent adenopathy after definitive chemoradiotherapy (CRT) for head and neck squamous cell carcinoma (HNSCC). Preoperative ultrasound-guided fine-needle aspiration (USFNA) can prevent unnecessary neck dissection. Postradiation fibrosis can complicate the approach, resulting in an inadequate aspirate volume when using standard 20- or 22-gauge needles. We assessed the comparative 18- and 20-gauge diagnostic accuracy of USFNA in detecting persistent viable nodal malignancy in patients with HNSCC with nodal metastasis treated with CRT. We hypothesized that 18-gauge USFNA would outperform 20-gauge USFNA in diagnostic accuracy and efficiency.

Materials and methods: We identified a 239-patient cohort (210 men, 60.4 ± 9.8 years) presenting between 2002-2023 with HNSCC and biopsy-proved cervical nodal metastases. All patients were treated with CRT. After CRT, a suspicious nodal remnant underwent biopsy with an 18- or 20-gauge needle. A total of 101 patients received a biopsy with a 20-gauge and 138 received a biopsy with an 18-gauge needle. Biopsy results were compared with either postbiopsy surgical pathology results when available or at least 3 months of CT follow-up, referred to here as post-USFNA results.

Results: Fine-needle aspiration (FNA) in 181 of 239 (75.7%) cases showed no evidence of viable metastatic disease on cytology evaluation. Twenty-gauge cases were performed with 1.36 ± 0.52 passes. Eighteen-gauge cases were performed with 1.26 ± 0.51 passes (P = .037). A neck dissection was performed within 90 days in 45 patients, while the other 194 patients had follow-up imaging. Forty/58 cases were positive concordant between FNA and post-USFNA results. Of 181 cases, 177 were negative concordant between FNA and post-USFNA results. Overall, USFNA showed a sensitivity of 90.9%, specificity of 90.8%, accuracy of 90.8%, positive predictive value (PPV) of 69.0%, and negative predictive value (NPV) of 97.8%. Twenty-gauge FNA showed positive concordant of 26 of 39 and negative concordant of 59 of 62 for a sensitivity of 89.7%, specificity of 81.9%, accuracy of 84.2%, PPV of 66.7%, and NPV of 95.2% Eighteen-gauge FNA showed a positive concordant of 14 of 19 and negative concordant of 118 of 119 for a sensitivity of 93.3%, specificity of 95.9%, accuracy of 95.7%, PPV of 73.7%, and NPV of 99.2%.

Conclusions: Residual cervical lymph node USFNA after CRT is an accurate procedure with excellent PPV and NPV. Eighteen-gauge USFNA is associated with statistically significant fewer biopsy passes and higher specificity compared with 20-gauge.

Background and purpose: The ARCADIA-MRI study, an ancillary study to the randomized Atrial Cardiopathy and Antithrombotic Drugs in Prevention After Cryptogenic Stroke (ARCADIA) trial, reported that the risk of incident nonlacunar covert infarcts was lower in the apixaban group than in the aspirin group. This article presents the additional, prespecified, exploratory outcomes beyond the primary article, specifically examining the effect of apixaban on hemorrhagic lesions on MRI.

Materials and methods: The ARCADIA-MRI study was conducted in conjunction with ARCADIA trial visits, with follow-up durations ranging from 4 months to 5.3 years (median, 27 months). It included randomized patients who were eligible for cognitive testing and lacked MRI contraindications. Two experienced raters, blinded to treatment assignments, independently evaluated the baseline and follow-up MRI scans. The radiologic end points of this analysis were incident intracranial hemorrhage (>10 mm), microbleeds (≤10 mm), and superficial siderosis.

Results: MRI outcomes were compared between the 79 patients in the apixaban group and 95 in the aspirin group with both baseline and follow-up MRIs available. The treatment groups had similar baseline MRI findings. On the follow-up MRIs, the findings of incident bleeding events were similar between the treatment groups (all, P > .05): Intracranial hemorrhage occurred in 5.1% of patients in the apixaban group compared with 6.4% of patients in the aspirin group; microbleeds, 7.8% in the apixaban group and 10.8% in the aspirin group; and cortical superficial siderosis, in 7.7% of apixaban group and 12.9% in the aspirin group.

Conclusions: In an exploratory analysis of the ARCADIA-MRI substudy, MRI findings of incident bleeding events were similar in patients randomized to receive apixaban and aspirin.

Background and purpose: The overexpression of prostate-specific membrane antigen (PSMA) in the microvasculature of glioblastoma (GBM), in contrast to its negligible expression in normal brain parenchyma, provides a compelling rationale for using PSMA-targeted radioligands in the diagnosis and radiation therapy of GBM. Arterial spin-labeling (ASL) perfusion imaging, an advanced MRI technique, allows noninvasive assessment of tumor microvascular density and perfusion. This study aimed to investigate the relationship between gallium 68 [⁶⁸]Ga-PSMA-11 PET and ASL perfusion imaging, as well as the correlation between PSMA tracer uptake and immunohistochemical microvascular indices.

Materials and methods: Twenty-six patients with newly diagnosed or recurrent GBM who underwent conventional MRI, ASL, and PSMA PET were prospectively enrolled. We investigated the correlation between the semiquantitative parameters of ASL and PSMA PET. Spatial similarity and overlap between tumor volumes delineated by contrast-enhanced (CE) MRI, ASL, and PSMA PET were evaluated using Dice Similarity Coefficient (DSC) and overlap volume (OV). Additionally, microvascular density values and PSMA expression levels in the tumor tissue samples were assessed using immunohistochemistry, and their correlation with PSMA tracer uptake was analyzed.

Results: A total of 28 lesions was found in 26 patients, all of whom showed high perfusion, moderate-to-high tracer uptake, and contrast enhancement. In 23 lesions (82%), the areas with the highest tracer uptake on PSMA PET were precisely localized to the regions of the highest perfusion on ASL. A strong positive correlation was found between the parameters derived from ASL and PSMA PET (P < .001). PSMA PET exhibited moderate-to-high spatial similarity and overlap with ASL (mean DSC, 0.62 [SD, 0.17]; mean OV, 0.78 [SD, 0.12]) and with CE MRI (mean DSC, 0.65 [SD, 0.14]; mean OV, 0.79 [SD, 0.15]). Furthermore, a positive correlation was observed between PSMA tracer uptake and both microvascular density and PSMA expression.

Conclusions: Our results highlight the similarity of biologic information captured by PSMA PET and ASL perfusion imaging in GBM. The tracer uptake observed in PSMA PET can also reliably reflect the spatial heterogeneity of the microvascular distribution of GBM. These findings provide compelling support for PSMA-targeted radiation therapy as an anti-angiogenic therapeutic strategy for patients with GBM, while also advancing our understanding of the mechanisms underlying PSMA tracer uptake.

Aim/objectives/background: This practice parameter was revised collaboratively by the American College of Radiology (ACR), the American College of Nuclear Medicine (ACNM), the American Society for Neuroradiology (ASNR), and the Society of Nuclear Medicine and Molecular Imaging (SNMMI).This important update now includes all FDA approved agents for PET imaging of dementia and reflects the expanding role of PET imaging for the early and more accurate diagnostic characterization of the neurodegenerative processes underlying cognitive deterioration. Clinical indications, personnel qualifications, and technical specifications are discussed in this practice parameter.

Methods: This practice parameter was revised according to the process described under the heading The Process for Developing ACR Practice Parameters and Technical Standards on the ACR website (https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards) by the Committee on Practice Parameters - Neuroradiology of the ACR Commission on Neuroradiology and the Committee on Practice Parameters - Nuclear Medicine and Molecular Imaging of the ACR Commission on Nuclear Medicine and Molecular Imaging in collaboration with the ACNM, the ASNR, and the SNMMI.

Results: ACR/ACNM/ASNR/SNMMI collaborative work to update the practice parameter of Brain PET imaging. The new parameter includes all FDA approved PET agents for the evaluation of dementia.

Conclusions: The updated practice parameter is intended to serve as a reference for clinical indications, technical specifications, and personnel qualifications state for PET/CT imaging in dementia.

Background and purpose: Deep learning (DL) reconstruction methods have shown promise in accelerating 2D MRI sequences but have yet to be extensively validated for routine 3D volumetric MRI applications. Our purpose was to assess the diagnostic quality of a novel DL-accelerated 3D T1-MPRAGE compared with a state-of-the-art wave-controlled aliasing in parallel imaging (Wave-CAIPI) accelerated 3D T1-MPRAGE for evaluating intracranial enhancing lesions.

Materials and methods: This prospective study was approved by the Institutional Review Board. Patients undergoing contrast-enhanced brain MRI in an outpatient setting were scanned on 3T MRI systems. The imaging protocol included a state-of-the-art Wave-CAIPI postcontrast T1-MPRAGE (acceleration factor [R] = 2 × 2, acquisition time [TA] = 2:11 minutes) and a research-based postcontrast DL-T1-MPRAGE (R = 2 × 2, TA = 2:11 minutes). The DL-based reconstruction process involved 2 steps. The first step, inspired by variational networks, involved 6 iterations alternating between data consistency updates and neural network evaluation. The second step applied a super-resolution algorithm for further image enhancement. Two independent neuroradiologists conducted a blinded, randomized head-to-head comparison of the 2 sequences by using a previously published scale across the following criteria: visualization of dural, parenchymal, leptomeningeal, and ependymal enhancement; sharpness; noise; artifacts; and overall diagnostic quality. A third board-certified neuroradiologist adjudicated cases with discrepant ratings. Noninferiority of DL-T1-MPRAGE was tested by using a 15% margin.

Results: A total of 115 patients (68 women/47 men, mean age = 54 ± 10 years) were included. The top 3 clinical indications were: neoplasm (52%), vascular lesions (24%), and headache (8%). DL-T1-MPRAGE was noninferior to Wave-CAIPI T1-MPRAGE for delineating enhancing lesions with unanimous agreement in all cases with enhancing pathology. It was also noninferior in terms of noise perception (P < .0001), artifact (P < .0001), sharpness (P = .001), and overall diagnostic quality (P < .0001). DL-T1-MPRAGE provided equivalent visualization of small, subtle enhancing parenchymal, dural, and leptomeningeal lesions.

Conclusions: The highly accelerated postcontrast DL-T1-MPRAGE demonstrated noninferior image quality compared with the clinically validated Wave-CAIPI T1-MPRAGE accelerated sequence while offering enhanced visualization of subtle enhancing lesions.

Background and purpose: Stroke is a leading cause of morbidity and mortality around the world, with LVO having a disproportionate impact on patient outcomes. Our aim was to assess the feasibility and accuracy of a deep learning (DL) model to identify acute MCA occlusion by using high-resolution NCCT imaging data.

Materials and methods: In this study, a total of 4648 consecutive examinations (July 2021 to December 2023) were retrospectively used for model training and validation, while an additional 1011 consecutive examinations (January 2024 to August 2024) were used for independent testing. By means of high-resolution NCCT acquired at a 1.0-mm slice thickness or less, MCA thrombus was labeled by using same-day CTA as ground truth. A 3D DL model was trained for per-voxel thrombus segmentation, with the sum of positive voxels used to estimate likelihood of acute MCA occlusion.

Results: For detection of MCA M1 segment acute occlusion, the model yielded an area under the receiver operator curve (AUROC) of 0.952 [0.904-1.00], accuracy of 93.6% [88.1%-98.2%], sensitivity of 90.9% [83.1%-100%], and specificity of 93.6% [88.0%-98.3%]. Inclusion of M2 segment occlusions reduced performance only slightly, yielding an AUROC of 0.884 [0.825-0.942], accuracy of 93.2% [85.1%-97.2%], sensitivity of 77.4% [69.3%-92.2%], and specificity of 93.6% [85.1%-97.8%].

Conclusions: A DL model can detect acute MCA occlusion from high-resolution NCCT with accuracy approaching that of CTA. By means of this tool, most candidate thrombectomy patients may be identified with NCCT alone, possibly aiding stroke triage in settings that lack CTA or are otherwise resource-constrained.

Background and purpose: Different types of software to analyze CTP data in patients with ischemic stroke are available. Assessing their comparability and interchangeability in clinical practice represents an only partly addressed question. Here we present a comparison between 2 distinct commercially available CTP types of software, analyzing their performance in estimating ischemic core volumes and evaluating the possible impact on patient stratification strategies to endovascular treatment (EVT).

Materials and methods: In this single-center retrospective monocentric observational study, 109 patients with stroke (mean age = 72.4 ± 12.4 years, M/F = 41/68) were included from January 2023 to June 2024. To evaluate the possible clinical relevance of the use of different types of software, DAWN and DEFUSE-3 criteria were applied to stratify the population. The software was compared (Viz.ai and syngo.via), and for both programs, different relative CBF thresholds were used to define the ischemic core.

Results: The 2 software programs showed significant differences in core volume identification, independently from the used threshold (all comparisons with P < .001). When the DAWN criteria for EVT were applied, the use of one software compared with another led to a significant (P = .005) increase in subjects excluded from EVT. The use of a more conservative threshold significantly reduced (P = .68) this discrepancy.

Conclusions: Within-subject analysis of CTP data with different software and thresholds might lead to significantly different core estimation and treatment stratification in patients with stroke. Though this effect can be mitigated by using specific thresholds, the physician should be aware of these differences when evaluating CTP data in clinical practice, given the possible direct implications in their decision-making process.

Background and purpose: The feasibility and safety of using 8F sheaths for endovascular treatment via the transradial approach (TRA) remain underexplored. This study evaluated whether the use of an 8F guiding catheter with or without an 8F sheath affects procedural success rates and access-site complications.

Materials and methods: We retrospectively reviewed 211 unruptured intracranial aneurysms in 207 patients treated via TRA with an 8F guiding catheter at 3 institutions between March 2021 and January 2025. Patients were divided into 2 groups: those treated with a sheath (Group S) and those without a sheath (Group NS). Propensity score matching was used to control for baseline differences when assessing the association between 8F sheath use and complication rates.

Results: A total of 44 aneurysms (21%) were treated via TRA by using an 8F guiding catheter with a sheath, achieving successful treatment in all cases. Propensity score matching resulted in 30 paired aneurysms from Group S and Group NS. The incidence of radial artery occlusion and radial artery spasm was significantly lower in Group S (0% and 20%, respectively) compared with Group NS (30% and 53%, respectively; P = .002 and .015). No significant differences were observed between the groups in access-site or non-access-site complications, nor in procedural success rates.

Conclusions: The use of an 8F guiding catheter with an 8F sheath for the treatment of unruptured intracranial aneurysms via the TRA appears feasible and may reduce the risk of radial artery occlusion and radial artery spasm without increasing the incidence of access-site or non-access-site complications.

Parathyroid lipoadenoma (PLA) is a rare cause of primary hyperparathyroidism and is over 50% adipose tissue, which complicates preoperative localization. We aimed to describe clinical and imaging features of PLA in this case series. We retrospectively reviewed 4 patients with pathologically confirmed PLA and biochemical evidence of primary hyperparathyroidism. All patients exhibited elevated PTH and upper-normal to elevated calcium levels. PLAs demonstrated hyperechogenicity on ultrasonography, fat-equivalent attenuation on CT, and increased uptake on sestamibi SPECT/CT. Surgical excision resulted in notable intraoperative PTH decline and postoperative biochemical cure. Pathology confirmed >50% stromal fat in all cases. In conclusion, PLA presents unique diagnostic challenges because of its imaging characteristics. Awareness of these features and a multimodal imaging approach are key to accurate localization and successful surgical management.