1Department of Neurosurgery, University Hospital of Lausanne.
2Department of Neurosurgery, Hospital General Universitario de Alicante, Spain.
Neurosurg Focus. 2020 Apr 1;48(4):E10. doi: 10.3171/2020.1.FOCUS19938.
Surgery for frontal lobe epilepsy remains a challenge because of the variable seizure outcomes after surgery. Disconnective procedures are increasingly applied to isolate the epileptogenic focus and avoid complications related to extensive brain resection. Previously, the authors described the anterior quadrant disconnection procedure to treat large frontal lobe lesions extending up to but not involving the primary motor cortex. In this article, they describe a surgical technique for unilateral disconnection of the prefrontal cortex, while providing an accurate description of the surgical and functional anatomy of this disconnective procedure.
The authors report the surgical treatment of a 5-month-old boy who presented with refractory epilepsy due to extensive cortical dysplasia of the left prefrontal lobe. In addition, with the aim of both describing the subcortical intrinsic anatomy and illustrating the different connections between the prefrontal lobe and the rest of the brain, the authors dissected six human cadaveric brain hemispheres. These dissections were performed from lateral to medial and from medial to lateral to reveal the various tracts sectioned during the three different steps in the surgery, namely the intrafrontal disconnection, anterior callosotomy, and frontobasal disconnection.
The first step of the dissection involves cutting the U-fibers. During the anterior intrafrontal disconnection, the superior longitudinal fasciculus in the depth of the middle frontal gyrus, the uncinate fasciculus, and the inferior frontooccipital fasciculus in the depth of the inferior frontal gyrus at the level of the anterior insular point are visualized and sectioned, followed by sectioning of the anterior limb of the internal capsule. Once the frontal horn is reached, the anterior callosotomy can be performed to disconnect the genu and the rostrum of the corpus callosum. The intrafrontal disconnection is deepened toward the falx, and at the medial surface, the cingulum is sectioned. The frontobasal disconnection involves cutting the anterior limb of the anterior commissure.
This technique allows selective isolation of the epileptogenic focus located in the prefrontal lobe to avoid secondary propagation. Understanding the surface and white matter fiber anatomy is essential to safely perform the procedure and obtain a favorable seizure outcome.
由于手术后癫痫发作的结果各不相同，额叶癫痫的手术治疗仍然是一个挑战。离断术越来越多地被应用于隔离致痫灶并避免与广泛脑切除相关的并发症。此前，作者描述了前象限离断术来治疗大的额叶病变，病变延伸至但不包括初级运动皮层。在本文中，他们描述了一种单侧前额叶皮层离断术的手术技术，并提供了该离断术的手术和功能解剖的准确描述。
作者报告了一名 5 个月大男孩的手术治疗，他因左侧前额叶皮质广泛发育不良导致难治性癫痫。此外，为了描述皮质下固有解剖结构，并说明前额叶与大脑其他部位之间的不同连接，作者解剖了 6 个人体大脑半球。这些解剖从外侧到内侧进行，然后从内侧到外侧进行，以显示手术的三个不同步骤中所切断的不同束：额内离断、胼胝体切开和额基底离断。
第一步是切断 U 纤维。在前额内离断过程中，在额上回深处可见上纵束、钩束和下额枕束，在额前岛点水平的下额回深处可见下额枕束，并切断内囊前肢。一旦到达额角，就可以进行胼胝体切开术，以切断胼胝体的膝部和嘴部。额内离断术向纵裂加深，在大脑内侧面，扣带回被切断。额基底离断术涉及切断前连合的前肢。
该技术允许选择性隔离位于前额叶的致痫灶，以避免继发性传播。了解表面和白质纤维解剖结构对于安全地进行手术并获得良好的癫痫发作结果至关重要。
