Ghielmetti Francesco, Aquino Domenico, Golfrè Andreasi Nico, Mazzi Federica, Greco Elena, Cilia Roberto, De Martin Elena, Rinaldo Sara, Stanziano Mario, Levi Vincenzo, Braccia Arianna, Marchetti Marcello, Fumagalli Maria L, Demichelis Greta, Colucci Fabiana, Romito Luigi Michele, Devigili Grazia, Elia Antonio E, Caldiera Valentina, Verri Mattia, Ciceri Elisa Francesca, Di Meco Francesco, Grisoli Marina, Bruzzone Maria Grazia, Eleopra Roberto
Health Department, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.
Neuroradiology Unit, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy.
Mov Disord Clin Pract. 2024 Dec;11(12):1516-1529. doi: 10.1002/mdc3.14219. Epub 2024 Oct 5.
Magnetic resonance-guided focused ultrasound (MRgFUS) targeting the thalamic ventral intermediate nucleus (VIM) is an innovative treatment for drug-refractory essential tremor (ET). The relationship between lesion characteristics, dentate-rubro-thalamic-tract (DRTT) involvement and clinical benefit remains unclear.
To investigate whether clinical outcome is related to lesion volume and/or its overlap with the DRTT. To compare the reliability of probabilistic versus deterministic tractography in reconstructing the DRTT and improving VIM targeting.
Forty ET patients who underwent MRgFUS thalamotomy between 2019 and 2022 were retrospectively analyzed. Clinical outcomes and adverse effects were recorded at 1/6/12 months after the procedure. The DRTT was generated using deterministic and probabilistic tractography on preoperative diffusion-tensor 3 T-images and location and volume of the lesion were calculated.
Probabilistic tractography identified both decussating (d-DRTT) and non-decussating (nd-DRTT) components of the DRTT, whereas the deterministic approach only identified one component overlapping with the nd-DRTT. Despite the lesions predominantly intersecting the medial portion of the d-DRTT, with a significantly greater overlap in responder patients, we observed only a non-significant correlation between tremor improvement and increased d-DRTT-lesion overlap (r = 0.22, P = 0.20). The lesion volume demonstrated a significant positive correlation with clinical improvement at 1-day MRI (r = 0.42, P < 0.01).
Variability in the reconstructed DRTT position relative to the lesion center of mass, even among good responders, suggests that this fiber bundle is unlikely to be considered the sole target for a successful MRgFUS thalamotomy in ET. Indirect individualized targeting allows for more precise and reproducible identification of actual treatment coordinates than the direct method.
磁共振引导聚焦超声（MRgFUS）靶向丘脑腹中间核（VIM）是治疗药物难治性特发性震颤（ET）的一种创新疗法。病灶特征、齿状红核丘脑束（DRTT）受累与临床疗效之间的关系尚不清楚。
研究临床疗效是否与病灶体积和/或其与DRTT的重叠有关。比较概率性与确定性纤维束成像在重建DRTT和改善VIM靶向方面的可靠性。
回顾性分析2019年至2022年间接受MRgFUS丘脑切开术的40例ET患者。在术后1/6/12个月记录临床疗效和不良反应。术前在3T扩散张量图像上使用确定性和概率性纤维束成像生成DRTT，并计算病灶的位置和体积。
概率性纤维束成像识别出DRTT的交叉（d-DRTT）和非交叉（nd-DRTT）成分，而确定性方法仅识别出与nd-DRTT重叠的一个成分。尽管病灶主要与d-DRTT的内侧部分相交，反应者患者的重叠明显更大，但我们仅观察到震颤改善与d-DRTT-病灶重叠增加之间无显著相关性（r = 0.22，P = 0.20）。病灶体积在术后1天的MRI上与临床改善呈显著正相关（r = 0.42，P < 0.01）。
即使在反应良好的患者中，重建的DRTT相对于病灶质心位置的变异性表明，该纤维束不太可能被视为ET中成功进行MRgFUS丘脑切开术的唯一靶点。间接个体化靶向比直接方法能更精确和可重复地识别实际治疗坐标。
