Klodowski Krzysztof, Zhang Minghao, Jen Jian P, Scoffings Daniel J, Morris Robert, Lupson Victoria, Mauconduit Franck, Massire Aurélien, Gras Vincent, Boulant Nicolas, Rodgers Christopher T, Cope Thomas E
Wolfson Brain Imaging Centre, University of Cambridge, Cambridge, UK.
Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK.
Epilepsia. 2025 Jul;66(7):2315-2327. doi: 10.1111/epi.18353. Epub 2025 Mar 20.
To implement parallel transmit (pTx) 7T magnetic resonance imaging (MRI) in the pre-surgical evaluation of 3T-negative patients with drug-resistant focal epilepsy, and to compare quality to conventional single transmit (specifically, circularly polarized [CP]) 7T MRI.
We implemented a comparative protocol comprising both pTx and CP 7T MRI in consecutive adult candidates for epilepsy surgery who had negative or equivocal 3T MRI imaging. Here we report the outcomes from the first 31 patients. We acquired pTx and CP T, T, fluid-attenuated inversion recovery (FLAIR) and edge-enhancing gradient echo (EDGE) images, all in the same three-dimensional (3D) 0.8 mm isotropic space. Two-dimensional (2D) high-resolution T and T*-weighted sequences were acquired only in CP mode due to current technological limitations. Two neuroradiologists, a neurologist, and a neurosurgeon made independent, blinded quality and preference ratings of pTx vs CP images. Quantitative methods were used to assess signal dropout.
7T revealed previously-unseen structural lesions in nine patients (29%), confirmed 3T-equivocal lesions in four patients (13%), and disproved 3T-equivocal lesions in four patients (13%). Lesions were better visualized on pTx than CP in 57% of cases, and never better visualized on CP. Clinical management was altered by 7T in 18 cases (58%). Nine cases were offered surgical resection and one laser interstitial thermal therapy (LITT). Three cases were removed from the surgical pathway because of bilateral or extensive lesions. Five cases were offered stereo-electroencephalography (sEEG) with better targeting (in three because the 7T lesion was deemed equivocal by the multi-disciplinary team (MDT), and in two because the lesion was extensive). Blinded comparison confirmed significantly better overall quality of pTx FLAIR images (F(2, 184) = 13.7, p = 2.88 × 10), whereas pTx MP2RAGE images were subjectively non-inferior and had improved temporal lobe coverage with quantitatively less signal drop-out.
pTx-7T is implementable in a clinical pathway, changed management in 58% of patients where 3T + FDG-PET had not enabled resection, and is superior to single transmit 7T MRI.
在术前评估3T磁共振成像（MRI）结果为阴性的耐药性局灶性癫痫患者中实施并行发射（pTx）7T磁共振成像，并将其质量与传统单发射（具体为圆极化[CP]）7T MRI进行比较。
我们对连续的成年癫痫手术候选患者实施了一项包含pTx和CP 7T MRI的对比方案，这些患者的3T MRI成像结果为阴性或不明确。在此，我们报告前31例患者的结果。我们采集了pTx和CP T1、T2、液体衰减反转恢复（FLAIR）和边缘增强梯度回波（EDGE）图像，所有图像均在相同的三维（3D）0.8毫米各向同性空间中采集。由于当前技术限制，二维（2D）高分辨率T1和T2*加权序列仅在CP模式下采集。两名神经放射科医生、一名神经科医生和一名神经外科医生对pTx与CP图像进行了独立、盲法的质量和偏好评分。采用定量方法评估信号丢失情况。
7T在9例患者（29%）中发现了先前未见的结构病变，在4例患者（13%）中证实了3T不明确的病变，在4例患者（13%）中排除了3T不明确的病变。在57%的病例中，pTx上的病变比CP上的病变显示得更好，而在CP上从未显示得更好。7T改变了18例（58%）患者的临床管理。9例患者接受了手术切除，1例接受了激光间质热疗（LITT）。3例患者因双侧或广泛病变被排除在手术路径之外。5例患者接受了立体定向脑电图（sEEG）检查，其靶向性更好（3例是因为多学科团队（MDT）认为7T病变不明确，2例是因为病变广泛）。盲法比较证实pTx FLAIR图像的总体质量明显更好（F(2, 184) = 13.7，p = 2.88 × 10），而pTx MP2RAGE图像在主观上不逊色，并且颞叶覆盖范围有所改善，信号丢失量在定量上更少。
pTx-7T可在临床路径中实施，在3T + FDG-PET未能实现切除的患者中，58%的患者管理得到了改变，并且优于单发射7T MRI。
