CPT Codes for MRI Safety—A User’s Guide

磁共振成像安全相关的现行操作术语编码——用户指南

The magnetic fields of the MR environment present unique safety challenges. Medical implants and retained foreign bodies can prevent patients from undergoing MR imaging due to interactions between the magnetic fields of the MR environment and the implant or foreign body. These hazards can be addressed through careful MR safety screening and MR examination customization, often allowing these patients with implants to undergo management-altering MR imaging. However, mitigating these risks takes additional time, expertise, and effort. Effective in 2025, this additional work is formally acknowledged with a new series of Current Procedural Terminology codes to report the work of assessing and addressing safety concerns associated with implants and foreign bodies in the MR environment. This user guide provides guidance on how to report these codes so physician-led MR safety teams can be appropriately reimbursed for the additional work performed in preparing patients with implants or foreign bodies for MR imaging.

磁共振（MR）环境中的磁场带来了独特的安全挑战。由于MR环境的磁场与植入物或异物之间会发生相互作用，体内有医用植入物和残留异物的患者可能无法接受MR成像检查。通过仔细的MR安全筛查和定制MR检查方案，可以应对这些风险，这通常能让这些有植入物的患者接受可改变治疗方案的MR成像检查。然而，降低这些风险需要额外的时间、专业知识和精力。从2025年起，通过一系列新的现行操作术语（CPT）编码正式认可这项额外工作，以记录评估和解决MR环境中与植入物和异物相关安全问题的工作。本用户指南为如何使用这些编码提供指导，以便由医生主导的MR安全团队为有植入物或异物的患者进行MR成像检查前准备工作所付出的额外劳动能得到合理补偿。

REF: Segovis CM, Ormsby JW, Yuan CX, Goette MJ, Chen MM, Edmonson HA. CPT Codes for MRI Safety-A User's Guide. AJNR Am J Neuroradiol. 2025;46(7):1289-1291. Published 2025 Jul 1. doi:10.3174/ajnr.A8661 PMID: 39832951

A Review of the Opportunities and Challenges with Large Language Models in Radiology: The Road Ahead

放射学中大型语言模型的机遇与挑战综述：未来之路

In recent years, generative artificial intelligence (AI), particularly large language models (LLMs) and their multimodal counterparts, multimodal large language models, including vision language models, have generated considerable interest in the global AI discourse. LLMs, or pre-trained language models (such as ChatGPT, Med-PaLM, LLaMA), are neural network architectures trained on extensive text data, excelling in language comprehension and generation. Multimodal LLMs, a subset of foundation models, are trained on multimodal data sets, integrating text with another modality, such as images, to learn universal representations akin to human cognition better. This versatility enables them to excel in tasks like chatbots, translation, and creative writing while facilitating knowledge sharing through transfer learning, federated learning, and synthetic data creation. Several of these models can have potentially appealing applications in the medical domain, including, but not limited to, enhancing patient care by processing patient data; summarizing reports and relevant literature; providing diagnostic, treatment, and follow-up recommendations; and ancillary tasks like coding and billing. As radiologists enter this promising but uncharted territory, it is imperative for them to be familiar with the basic terminology and processes of LLMs. Herein, we present an overview of the LLMs and their potential applications and challenges in the imaging domain.

近年来，生成式人工智能（AI），特别是大语言模型（LLM）及其多模态对应模型——多模态大语言模型（包括视觉语言模型），在全球人工智能讨论中引起了广泛关注。大语言模型，即预训练语言模型（如ChatGPT、Med - PaLM、LLaMA），是基于大量文本数据进行训练的神经网络架构，在语言理解和生成方面表现出色。多模态大语言模型是基础模型的一个子集，它在多模态数据集上进行训练，将文本与其他模态（如图像）相结合，以便更好地学习类似于人类认知的通用表征。这种多功能性使它们在聊天机器人、翻译和创意写作等任务中表现卓越，同时通过迁移学习、联邦学习和合成数据创建来促进知识共享。其中一些模型在医学领域可能有颇具吸引力的应用，包括但不限于通过处理患者数据改善患者护理；总结报告和相关文献；提供诊断、治疗和随访建议；以及编码和计费等辅助任务。随着放射科医生进入这个充满希望但未知的领域，他们必须熟悉大语言模型的基本术语和流程。在此，我们概述了大语言模型及其在影像领域的潜在应用和挑战。

REF: Soni N, Ora M, Agarwal A, Yang T, Bathla G. A Review of the Opportunities and Challenges with Large Language Models in Radiology: The Road Ahead. AJNR Am J Neuroradiol. 2025;46(7):1292-1299. Published 2025 Jul 1. doi:10.3174/ajnr.A8589 PMID: 39572201

Neuroimaging Spectrum of Erdheim-Chester Disease: An Image-Based Review

埃尔迪姆 - 切斯特病的神经影像学表现谱：基于影像的综述

Erdheim-Chester disease (ECD) is a rare, multisystem histiocytic disorder characterized by its variable clinical presentations. CNS involvement is observed in approximately one-half of patients with ECD (up to 76% in some series) and often carries a poorer prognosis. While CNS involvement may remain asymptomatic, others may experience a range of neurologic symptoms, including cognitive decline, neuropsychiatric disturbances, motor deficits, cranial or peripheral neuropathies, and endocrine abnormalities. Neuroimaging findings in CNS-ECD are diverse, including neurodegeneration manifesting as cerebral or cerebellar volume loss; solitary or multifocal variably enhancing intraparenchymal lesions along the neuroaxis; meningeal infiltration; and involvement of the hypothalamo-pituitary axis, perivascular sheathing, or basal ganglia lesions. Other well-documented sites of involvement include the craniofacial region, orbits, and spine. Awareness of these findings is relevant, not only because of the nonspecific nature of these findings, but also because of the high proportion of CNS involvement in ECD and the higher mortality associated with CNS involvement. This review provides an in-depth overview of the various manifestations of CNS involvement in ECD and their imaging features, along with a brief overview of the differential considerations, which include other histiocytic and nonhistiocytic processes.

埃尔迪海姆 - 切斯特病（ECD）是一种罕见的多系统组织细胞疾病，其临床症状表现多样。约一半的ECD患者会出现中枢神经系统（CNS）受累（部分系列研究中该比例高达76%），且通常预后较差。虽然部分CNS受累患者可能无症状，但也有患者会出现一系列神经系统症状，包括认知功能下降、神经精神障碍、运动功能障碍、颅神经或周围神经病变以及内分泌异常。CNS - ECD的神经影像学表现多样，包括以大脑或小脑体积缩小为表现的神经退行性变；沿神经轴分布的单发或多发、强化程度不一的实质内病变；脑膜浸润；下丘脑 - 垂体轴受累、血管周围套袖样改变或基底节病变。其他有充分记录的受累部位包括颅面区域、眼眶和脊柱。了解这些表现很重要，不仅因为这些表现缺乏特异性，还因为ECD患者中CNS受累比例高，且CNS受累与更高的死亡率相关。本综述深入概述了ECD患者CNS受累的各种表现及其影像学特征，并简要介绍了鉴别诊断要点，鉴别诊断包括其他组织细胞性和非组织细胞性病变。

REF: Rai P, Swartz HJ, Soni N, et al. Neuroimaging Spectrum of Erdheim-Chester Disease: An Image-Based Review. AJNR Am J Neuroradiol. 2025;46(7):1300-1308. Published 2025 Jul 1. doi:10.3174/ajnr.A8599 PMID: 39578102

Sodium MRI in Pediatric Brain Tumors

小儿脑肿瘤的钠磁共振成像

Direct sodium MRI (23Na-MRI) derives its signal from spin-manipulation of the 23Na nucleus itself and not the more conventional and familiar 1H-MRI. Although present at much lower concentrations in the human body than the 1H nuclei in the water molecule H2O, advances in coil design and pulse sequence development have enabled the feasibility of human in vivo 23Na-MRI. Additionally, 23Na-MRI has the potential to offer nuanced physiologic insights not available to conventional MRI; this feature forms the basis of interest in its development and optimism for its novel clinical utility. 23Na-MRI has the potential to be a useful noninvasive imaging technique to assess biochemical and physiologic cellular changes in tissues, eg, cell integrity and tissue viability. Pathologically, the concentration of total sodium is elevated in tumors relative to normal counterparts due to increased intracellular sodium and/or an increased proportion of extracellular space (reflecting changes in cell morphology and anomalies of homeostasis). Here we review the technological advancements with improved pulse sequences and reconstruction methods that counter the inherent challenges of measuring sodium concentrations in the pediatric brain (in particular, its short-tissue T2 value) and present detailed imaging approaches to quantifying sodium concentrations in the pediatric brain that can be assessed in various CNS pathologies, with the focus on pediatric brain tumors.

直接钠磁共振成像（23Na - MRI）的信号源自对 23Na 原子核本身的自旋操控，而非更为常规和常见的 1H - MRI。尽管 23Na 在人体中的浓度远低于水分子 H2O 中的 1H 原子核，但线圈设计和脉冲序列开发的进展使人体体内 23Na - MRI 成为可能。此外，23Na - MRI 有可能提供常规 MRI 所无法获得的细致生理信息；这一特性是人们对其发展感兴趣并对其新颖临床应用前景持乐观态度的基础。23Na - MRI 有望成为一种有用的非侵入性成像技术，用于评估组织中的生化和生理细胞变化，例如细胞完整性和组织活力。在病理情况下，由于细胞内钠增加和/或细胞外间隙比例增加（反映细胞形态变化和体内平衡异常），肿瘤中的总钠浓度相对于正常组织会升高。在此，我们回顾了脉冲序列和重建方法的技术进步，这些进步克服了测量小儿大脑钠浓度的固有挑战（特别是其组织 T2 值较短的问题），并介绍了量化小儿大脑钠浓度的详细成像方法，这些方法可用于评估各种中枢神经系统病理状况，重点是小儿脑肿瘤。

REF: Bhatia A, Kline C, Madsen PJ, Fisher MJ, Boada FE, Roberts TPL. Sodium MRI in Pediatric Brain Tumors. AJNR Am J Neuroradiol. 2025;46(7):1309-1317. Published 2025 Jul 1. doi:10.3174/ajnr.A8642 PMID: 40537288

High-Resolution MR Imaging of the Parasellar Ligaments

鞍旁韧带的高分辨率磁共振成像

The parasellar ligaments have been previously described in cadaver specimens and intraoperatively, but identification on MR imaging has eluded radiologists. Using high-resolution T2-weighted MR imaging, we identified the parasellar ligaments as T2-hypointense, bandlike structures that emanate from the medial wall of the cavernous sinus. Subsequent dissection of the same specimen provided matching anatomic images of the parasellar ligaments identified on MRI. This imaging finding is important because resection of the medial wall of the cavernous sinus has been tied to improved outcomes for gross total resection and endocrinologic remission of functioning pituitary adenomas.

此前已在尸体标本和术中对鞍旁韧带进行了描述，但放射科医生一直未能在磁共振成像（MRI）上识别出它们。利用高分辨率T2加权MRI，我们将鞍旁韧带识别为从海绵窦内侧壁发出的T2低信号带状结构。随后对同一标本进行解剖，获得了与MRI上识别出的鞍旁韧带相匹配的解剖图像。这一影像学发现很重要，因为切除海绵窦内侧壁与功能性垂体腺瘤的全切除和内分泌缓解的良好预后相关。

REF: Mark IT, In MH, Kang D, et al. High-Resolution MR Imaging of the Parasellar Ligaments. AJNR Am J Neuroradiol. 2025;46(7):1318-1320. Published 2025 Jul 1. doi:10.3174/ajnr.A8658 PMID: 40537286

Cracking the Code of Calcification: How Presence and Burden among Intracranial Arteries Influence Stroke Incidence and Recurrence

破解钙化密码：颅内动脉钙化的存在情况和程度如何影响中风的发病率和复发率

This systematic review and meta-analysis analyzed published articles on intracranial arterial segments to understand the role of plaque calcification in stroke events. Weak association between intracranial calcification and stroke incidence/recurrence was found as well as weak association between calcium burden and stroke incidence/recurrence.

这项系统评价和荟萃分析对已发表的关于颅内动脉节段的文章进行了分析，以了解斑块钙化在中风事件中的作用。研究发现，颅内钙化与中风发生率/复发率之间存在弱关联，钙负荷与中风发生率/复发率之间也存在弱关联。

REF: Conte M, Alalfi MO, Cau R, et al. Cracking the Code of Calcification: How Presence and Burden among Intracranial Arteries Influence Stroke Incidence and Recurrence. AJNR Am J Neuroradiol. 2025;46(7):1321-1328. Published 2025 Jul 1. doi:10.3174/ajnr.A8668 PMID: 39855892

Location-Specific Net Water Uptake and Malignant Cerebral Edema in Acute Anterior Circulation Occlusion Ischemic Stroke

急性前循环闭塞性缺血性卒中特定部位的净水摄取与恶性脑水肿

Early identification of malignant cerebral edema (MCE) in patients with acute ischemic stroke is crucial for timely interventions. We aimed to identify regions critically associated with MCE using the ASPECTS to evaluate the association between location-specific net water uptake (NWU) and MCE. The insula region is critical for MCE, and Insula-NWU has better prediction efficacy than ASPECTS-NWU. This method does not rely on advanced imaging, facilitating rapid assessment in emergencies.

急性缺血性中风患者恶性脑水肿（MCE）的早期识别对于及时干预至关重要。我们旨在使用急性卒中早期CT评分（ASPECTS）识别与MCE密切相关的脑区，以评估特定部位的净水摄取（NWU）与MCE之间的关联。岛叶区域对MCE的发生至关重要，且岛叶NWU的预测效能优于ASPECTS - NWU。该方法不依赖于高级影像学检查，便于在紧急情况下进行快速评估。

REF: Cheng X, Tian B, Huang L, et al. Location-Specific Net Water Uptake and Malignant Cerebral Edema in Acute Anterior Circulation Occlusion Ischemic Stroke. AJNR Am J Neuroradiol. 2025;46(7):1329-1335. Published 2025 Jul 1. doi:10.3174/ajnr.A8659 PMID: 39832952

A Method for Imaging the Ischemic Penumbra with MRI Using Intravoxel Incoherent Motion

一种利用体素内不相干运动磁共振成像技术对缺血半暗带进行成像的方法

In acute ischemic stroke, the amount of "local" CBF distal to the occlusion, ie, all blood flow, whether supplied antegrade or delayed and dispersed through the collateral network, may contain valuable information regarding infarct growth rate and treatment response. DSC processed with a local arterial input function (AIF) is one method of measuring local CBF (local-qCBF) and has been shown to correlate with collateral supply. Similarly, intravoxel incoherent motion MRI (IVIM) is "local," with excitation and readout in the same plane, and a potential alternative way to measure local-qCBF. This work compares IVIM local-qCBF against DSC local-qCBF in the ischemic penumbra, compares the measurement of perfusion-diffusion mismatch (PWI/DWI), and examines if local-qCBF may improve prediction of the final infarct. Noncontrast IVIM measurement of local-qCBF and PWI/DWI mismatch may include collateral circulation and improve prediction of infarct growth.

在急性缺血性卒中中，闭塞部位远端的“局部”脑血流量（CBF），即所有血流，无论是顺行供应的血流，还是通过侧支循环网络延迟并分散供应的血流，都可能包含有关梗死灶增长速度和治疗反应的有价值信息。采用局部动脉输入函数（AIF）处理的动态磁敏感对比增强磁共振成像（DSC）是测量局部CBF（局部定量CBF，local-qCBF）的一种方法，且已证实其与侧支循环供应相关。同样，体素内不相干运动磁共振成像（IVIM）也是“局部”的，其激发和读出在同一平面，是测量local-qCBF的一种潜在替代方法。本研究比较了缺血半暗带中IVIM测得的local-qCBF与DSC测得的local-qCBF，对比了灌注 - 弥散不匹配（PWI/DWI）的测量结果，并探讨了local-qCBF是否能改善对最终梗死灶的预测。采用非对比剂IVIM测量local-qCBF和PWI/DWI不匹配情况，可能能够反映侧支循环，并改善对梗死灶增长的预测。

REF: Liu MM, Saadat N, Roth SP, et al. A Method for Imaging the Ischemic Penumbra with MRI Using Intravoxel Incoherent Motion. AJNR Am J Neuroradiol. 2025;46(7):1336-1344. Published 2025 Jul 1. doi:10.3174/ajnr.A8656 PMID: 39805668

Arterial Spin-Labeling MRI Identifies Abnormal Perfusion Metric at the Gray Matter/CSF Interface in Cerebral Small Vessel Disease

动脉自旋标记磁共振成像可识别脑小血管病中灰质/脑脊液界面的异常灌注指标

Cerebral small vessel disease (SVD) is a common cause of stroke and cognitive decline. SVD is characterized by white matter hyperintensities (WMH) and dilated perivascular spaces (PVS). While WMH can be associated with reduced CBF and glymphatic clearance, current clinical and radiologic assessments of these associations remain controversial and mostly qualitative. We aim to identify if arterial spin-labeling (ASL)-based CBF differences, particularly in the cortical surface at the GM/CSF interface, correlate with SVD severity. nGCI, a novel perfusion metric that may capture features of perfusion at the GM-CSF boundary, was strongly correlated with WMH and PVS severity. Further, longitudinal studies are required to determine the potential role of nGCI as a predictive marker of SVD progression.

脑小血管病（SVD）是中风和认知衰退的常见原因。SVD的特征是脑白质高信号（WMH）和血管周围间隙扩大（PVS）。虽然WMH可能与脑血流量（CBF）减少和类淋巴清除功能下降有关，但目前针对这些关联的临床和影像学评估仍存在争议，且大多为定性评估。我们旨在确定基于动脉自旋标记（ASL）的CBF差异，尤其是在灰质/脑脊液（GM/CSF）界面的皮质表面的差异，是否与SVD的严重程度相关。归一化灰质 - 脑脊液界面脑血流量指数（nGCI）是一种新的灌注指标，可能反映GM - CSF边界的灌注特征，它与WMH和PVS的严重程度密切相关。此外，需要开展纵向研究来确定nGCI作为SVD进展预测标志物的潜在作用。

REF: Mahammedi A, Fettahoglu A, Heit JJ, Wardlaw JM, Zaharchuk G. Arterial Spin-Labeling MRI Identifies Abnormal Perfusion Metric at the Gray Matter/CSF Interface in Cerebral Small Vessel Disease. AJNR Am J Neuroradiol. 2025;46(7):1345-1352. Published 2025 Jul 1. doi:10.3174/ajnr.A8682 PMID: 40506229