Xu San San, Akram Harith, Lind Valentina, Hyam Jonathan, Davagnanam Indran, Korlipara Prasad, Saifee Tabish A, Foltynie Thomas, Zrinzo Ludvic, Limousin Patricia, Krüger Marie T
UCL Functional Neurosurgery Unit, National Hospital for Neurology and Neurosurgery, London, UK.
Department of Clinical and Movement Neurosciences, University College London, London, UK.
BMJ Neurol Open. 2025 Jul 28;7(2):e001104. doi: 10.1136/bmjno-2025-001104. eCollection 2025.
Magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy of the ventral intermediate nucleus (Vim) is an effective therapy for medication-refractory essential tremor (ET). The Vim is not readily visualised on conventional MRI and targeting is routinely performed indirectly, with atlas co-ordinates. Inaccurate targeting due to interindividual anatomical variability can result in side effects and reduced efficacy. FAT1-weighted MRI is a high-resolution, high-fidelity modality that combines fractional anisotropy mapping and anatomical T1 sequences and allows direct visualisation of the Vim. Here, we assessed the outcomes of ET patients treated with a novel FAT1-weighted MRgFUS thalamotomy technique.
Targeting was performed through direct visualisation of the Vim on FAT1-weighted MRI sequence. Clinical, technical and imaging data were collected prospectively at baseline, 6 and 12 months follow-up.
The first 14 consecutive ET patients undergoing MRgFUS at our centre were assessed. Their mean age was 73.6 years and disease duration was 31.8 years. There were significant improvements in treated hand tremor score (60%), disability score (71%) and quality of life (72%) and no clinically relevant side effects at 12 months. A mean of 6.9 sonications was performed and the mean time from first to last sonication was 34.6 min. Greater tremor improvement was observed with lesions in the inferior and lateral part of the Vim.
This is the first case series assessing FAT1-guided Vim targeting in MRgFUS thalamotomy. These results demonstrate that this method is safe and clinically effective, with added technical advantages including low sonication numbers and short procedural time.
磁共振引导聚焦超声（MRgFUS）丘脑腹中间核（Vim）毁损术是治疗药物难治性特发性震颤（ET）的有效方法。在传统MRI上，Vim不易显示，通常通过图谱坐标间接进行靶点定位。个体间解剖变异导致的靶点定位不准确可导致副作用并降低疗效。FAT1加权MRI是一种高分辨率、高保真的成像方式，它结合了分数各向异性成像和解剖T1序列，能够直接显示Vim。在此，我们评估了采用新型FAT1加权MRgFUS丘脑毁损术治疗ET患者的疗效。
通过在FAT1加权MRI序列上直接观察Vim进行靶点定位。前瞻性收集基线、随访6个月和12个月时的临床、技术和影像数据。
对在我们中心接受MRgFUS治疗的首批14例连续ET患者进行了评估。他们的平均年龄为73.6岁，病程为31.8年。治疗后手部震颤评分（改善60%）、残疾评分（改善71%）和生活质量（改善72%）均有显著改善，且在12个月时无临床相关副作用。平均进行了6.9次超声聚焦，从首次到末次超声聚焦的平均时间为34.6分钟。观察到Vim下部和外侧的毁损灶对震颤改善效果更佳。
这是首个评估MRgFUS丘脑毁损术中FAT1引导Vim靶点定位的病例系列研究。这些结果表明，该方法安全且临床有效，还具有超声聚焦次数少和手术时间短等技术优势。
