Huang Yuhao, Yecies Derek, Bruckert Lisa, Parker Jonathon J, Ho Allen L, Kim Lily H, Fornoff Linden, Wintermark Max, Porter Brenda, Yeom Kristen W, Halpern Casey H, Grant Gerald A
Departments of1Neurosurgery.
2Pediatrics.
J Neurosurg Pediatr. 2019 Aug 2;24(4):433-441. doi: 10.3171/2019.5.PEDS19117. Print 2019 Oct 1.
Completion corpus callosotomy can offer further remission from disabling seizures when a prior partial corpus callosotomy has failed and residual callosal tissue is identified on imaging. Traditional microsurgical approaches to section residual fibers carry risks associated with multiple craniotomies and the proximity to the medially oriented motor cortices. Laser interstitial thermal therapy (LITT) represents a minimally invasive approach for the ablation of residual fibers following a prior partial corpus callosotomy. Here, the authors report clinical outcomes of 6 patients undergoing LITT for completion corpus callosotomy and characterize the radiological effects of ablation.
A retrospective clinical review was performed on a series of 6 patients who underwent LITT completion corpus callosotomy for medically intractable epilepsy at Stanford University Medical Center and Lucile Packard Children's Hospital at Stanford between January 2015 and January 2018. Detailed structural and diffusion-weighted MR images were obtained prior to and at multiple time points after LITT. In 4 patients who underwent diffusion tensor imaging (DTI), streamline tractography was used to reconstruct and evaluate tract projections crossing the anterior (genu and rostrum) and posterior (splenium) parts of the corpus callosum. Multiple diffusion parameters were evaluated at baseline and at each follow-up.
Three pediatric (age 8-18 years) and 3 adult patients (age 30-40 years) who underwent completion corpus callosotomy by LITT were identified. Mean length of follow-up postoperatively was 21.2 (range 12-34) months. Two patients had residual splenium, rostrum, and genu of the corpus callosum, while 4 patients had residual splenium only. Postoperative complications included asymptomatic extension of ablation into the left thalamus and transient disconnection syndrome. Ablation of the targeted area was confirmed on immediate postoperative diffusion-weighted MRI in all patients. Engel class I-II outcomes were achieved in 3 adult patients, whereas all 3 pediatric patients had Engel class III-IV outcomes. Tractography in 2 adult and 2 pediatric patients revealed time-dependent reduction of fractional anisotropy after LITT.
LITT is a safe, minimally invasive approach for completion corpus callosotomy. Engel outcomes for completion corpus callosotomy by LITT were similar to reported outcomes of open completion callosotomy, with seizure reduction primarily observed in adult patients. Serial DTI can be used to assess the presence of tract projections over time but does not classify treatment responders or nonresponders.
当先前的部分胼胝体切开术失败且影像学检查发现残留胼胝体组织时，完成胼胝体切开术可使致残性癫痫进一步缓解。传统的显微手术方法用于切断残留纤维，存在与多次开颅手术相关的风险以及靠近内侧运动皮质的风险。激光间质热疗法（LITT）是一种用于在先前部分胼胝体切开术后消融残留纤维的微创方法。在此，作者报告了6例接受LITT进行完成胼胝体切开术患者的临床结果，并描述了消融的放射学效应。
对2015年1月至2018年1月期间在斯坦福大学医学中心和斯坦福露西尔·帕卡德儿童医院接受LITT完成胼胝体切开术治疗药物难治性癫痫的6例患者进行回顾性临床研究。在LITT之前及术后多个时间点获取详细的结构和扩散加权磁共振成像（MRI）。在4例接受扩散张量成像（DTI）的患者中，使用流线追踪技术重建并评估穿过胼胝体前部（膝部和嘴部）和后部（压部）的纤维束投影。在基线和每次随访时评估多个扩散参数。
确定了3例儿科患者（年龄8 - 18岁）和3例成年患者（年龄30 - 40岁）接受了LITT完成胼胝体切开术。术后平均随访时间为21.2（范围12 - 34）个月。2例患者残留胼胝体的压部、嘴部和膝部，而4例患者仅残留压部。术后并发症包括消融无症状延伸至左侧丘脑和短暂性分离综合征。所有患者术后即刻的扩散加权MRI证实了目标区域的消融。3例成年患者达到Engel I - II级结果，而所有3例儿科患者为Engel III - IV级结果。2例成年患者和2例儿科患者的纤维束成像显示LITT后各向异性分数随时间降低。
LITT是一种安全、微创的完成胼胝体切开术的方法。LITT完成胼胝体切开术的Engel结果与开放性完成胼胝体切开术报告的结果相似，癫痫减少主要见于成年患者。连续DTI可用于评估随时间推移纤维束投影的存在情况，但不能区分治疗反应者和无反应者。
