Cheshier Samuel H, Hanft Simon J, Adler John R, Chang Steven D
Department of Neurosurgery, Stanford University School of Medicine, Stanford, CA 94305, USA.
Technol Cancer Res Treat. 2007 Aug;6(4):329-36. doi: 10.1177/153303460700600410.
The region of the foramen magnum (FM) presents an especially difficult area for therapeutic intervention. Indeed, this location is challenging to access surgically, particularly in the case of intramedullary and anterior lesions. Therefore, the potential for morbidity associated with therapy to the foramen magnum, most frequently in the form of lower cranial nerve deficits, has encouraged the search for methods that can effectively treat lesions of this region while sparing the important neighboring structures. We report our experience in the use of Cyberknife radiosurgery as a treatment option for these lesions. Thirty-five patients (17 men, 18 women; mean age, 51 yr; range, 18-83) with 35 lesions either spanning or approximating the foramen magnum were treated with the CyberKnife radiosurgical system. Histologies were determined either by prior surgery or radiographic criteria and included 25 benign tumors (nine meningiomas, five schwannomas, four neurofibromas, three hemangioblastomas, two ependymomas, one chordomas, and one pilocytic astrocytoma) along with 10 malignant growths (nine metastases and one chondrosarcoma). Twenty-seven (77%) patients presented with at least one sign and/or symptom, while eight (23%) patients were completely asymptomatic. The most common symptoms were headache, limb numbness, and limb/truncal ataxia, all of which were reported by ten (29%) patients. Among cranial neuropathies, CN XII dysfunction was evident in four (11%) patients. The specific fractionation schedule (mean of 1.8 sessions; range, 1-5) was based on the size of the treated lesion. The mean dose utilized was 19 Gy. Radiographic follow-up was obtained for twenty-three (66%) patients. Nine of the twenty-three (39%) were stable in size, ten lesions decreased in size (43%), and four lesions increased in size (17%). In terms of symptom relief, follow-up was collected for twenty-four (69%) patients. Eleven (46%) of these patients experienced no change in their signs or symptoms, while seven (29%) patients experienced improvement. Six (25%) patients witnessed deterioration in their signs and symptoms. Overall, eighteen (75%) patients had their signs and symptoms either stabilize or improve. There were eleven (31%) deaths in our series, eight of which were related to the disease (though not directly related to CyberKnife treatment) and three of which were from unrelated causes. Complications directly related to CyberKnife radiosurgery were noted in four (11%) of the thirty-five patients. These included one case of temporary emesis immediately following treatment, one case of cystic enlargement two months out, and two cases of radiation necrosis (occurring 1.5 yrs and 2.5 yrs out from treatment). Cyberknife radiosurgery can be an effective treatment for many foramen magnum lesions.
枕骨大孔（FM）区域是治疗干预特别困难的部位。实际上，这个位置手术入路具有挑战性，尤其是对于髓内和前部病变。因此，与枕骨大孔治疗相关的发病风险，最常见的形式是低位颅神经功能缺损，这促使人们寻找能够有效治疗该区域病变同时保留重要相邻结构的方法。我们报告了使用射波刀放射外科治疗这些病变的经验。35例患者（17例男性，18例女性；平均年龄51岁；范围18 - 83岁），有35个跨越或接近枕骨大孔的病变，接受了射波刀放射外科系统治疗。组织学诊断通过既往手术或影像学标准确定，包括25例良性肿瘤（9例脑膜瘤、5例神经鞘瘤、4例神经纤维瘤、3例血管母细胞瘤、2例室管膜瘤、1例脊索瘤和1例毛细胞型星形细胞瘤）以及10例恶性肿瘤（9例转移瘤和1例软骨肉瘤）。27例（77%）患者至少有一项体征和/或症状，而8例（23%）患者完全无症状。最常见的症状是头痛、肢体麻木和肢体/躯干共济失调，所有这些症状均有10例（29%）患者报告。在颅神经病变中，4例（11%）患者出现明显的舌下神经功能障碍。具体的分割方案（平均1.8次治疗；范围1 - 5次）基于治疗病变的大小。使用的平均剂量为19 Gy。对23例（66%）患者进行了影像学随访。23例中的9例（39%）病变大小稳定，10例病变缩小（43%），4例病变增大（17%）。在症状缓解方面，对24例（69%）患者进行了随访。其中11例（46%）患者的体征或症状无变化，7例（29%）患者症状改善。6例（25%）患者的体征和症状恶化。总体而言，18例（75%）患者的体征和症状稳定或改善。我们的系列中有11例（31%）死亡，其中8例与疾病相关（尽管与射波刀治疗无直接关系），3例为无关原因。35例患者中有4例（11%）出现了与射波刀放射外科直接相关的并发症。这些包括1例治疗后立即出现的短暂呕吐、治疗后两个月出现的1例囊肿增大以及治疗后1.5年和2.5年出现的2例放射性坏死。射波刀放射外科对于许多枕骨大孔病变可能是一种有效的治疗方法。
