Kim D G, Choe W J, Paek S H, Chung H T, Kim I H, Han D H
Department of Neurosurgery, Seoul National University College of Medicine, Clinical Research Institute, Seoul National University Hospital, Seoul, Korea.
Acta Neurochir (Wien). 2002 Sep;144(9):869-78; discussion 878. doi: 10.1007/s00701-002-0983-9.
The efficacy of radiosurgery in cases of surgically high risk symptomatic cavernous malformations (CMs) for reducing haemorrhagic risk and for seizure control has not been clearly documented and the radiation-induced complications of radiosurgery remain problematic. The authors present a retrospective clinical analysis of 22 cases of CMs treated by radiosurgery.
Twenty-two patients with symptomatic CMs were treated by linear accelerator (LINAC) radiosurgery or Gamma knife (GK) between 1995 and 1998. Medical records including radiological investigations were carefully reviewed to the last follow-up. The mean age of the patients was 34.1 years (12-56) and the male to female ratio was 12:10. Twenty patients reported at least one episode of bleeding and four had undergone microsurgery before radiosurgery. The remaining two patients presented with seizure without evidence of recent haemorrhage. In 16 cases, the CMs were deep-seated, and the others were located in the cerebral hemispheres; four were located at an eloquent area. LINAC radiosurgery using computed tomography scan was performed in 11 cases until May 1997, after which GK radiosurgery using magnetic resonance (MR) image was performed in 11 cases. The volume of the lesion ranged from 0.09 cc to 4.8 cc (mean 1.42 cc) and the mean marginal dose was 16.1 Gy (8-24). The median follow-up period after radiosurgery was 38.3 months (21-67). The rate of haemorrhage, seizure, and neurological deterioration following radiosurgery was analyzed, and the rate of haemorrhage was compared to that seen in natural course reports.
There was one case of haemorrhage during the follow-up period and the seizure was well controlled with anticonvulsants. In the group with prior haemorrhage, the bleeding rate of cavernous malformation after radiosurgery (1.55%/year) was lower than that of pre-radiosurgical period (35.5%/year, t=1.296, P=0.04). Six patients showed neurological deterioration following radiosurgery, however, the neurological deficits persisted in only two of the patients with LINAC. The radiosurgical modality (LINAC vs. GK) showed a possible correlation to radiation induced neurological deficits (P=0.06). On the MR images at the last follow-up, the lesion was decreased in eleven patients, increased in one, and no change was found in 10 cases. The T2 weighted MR images revealed a perilesional high signal change in nine patients. This signal change was not statistically related to lesion size (P=0.236), location (P=0.658), nor radiation dose (P=0.363), but was dependent on the treatment modality (P=0.02). New-enhancing lesion and a new cyst were each found in one case, respectively, during the follow-up.
Radiosurgery may be a good alternative option for treatment of surgically high risk CMs. However, the optimal radiosurgical technique, dose adjustment, and proper delineation of the mass are prerequisites. Radiosurgery induced complications are still problematic and post-radiosurgery MR image changes need to be further elucidated.
对于手术风险高的有症状海绵状血管畸形（CMs）患者，放射外科手术在降低出血风险和控制癫痫发作方面的疗效尚未得到明确证实，且放射外科手术的辐射诱导并发症仍然存在问题。作者对22例接受放射外科手术治疗的CMs患者进行了回顾性临床分析。
1995年至1998年间，22例有症状的CMs患者接受了直线加速器（LINAC）放射外科手术或伽玛刀（GK）治疗。仔细查阅包括放射学检查在内的病历，直至最后一次随访。患者的平均年龄为34.1岁（12 - 56岁），男女比例为12:10。20例患者报告至少有一次出血事件，4例在放射外科手术前接受过显微手术。其余2例患者表现为癫痫发作，无近期出血证据。16例CMs位于深部，其余位于脑半球；4例位于功能区。1997年5月前，11例患者采用计算机断层扫描进行LINAC放射外科手术，之后11例患者采用磁共振（MR）图像进行GK放射外科手术。病变体积从0.09立方厘米至4.8立方厘米不等（平均1.42立方厘米），平均边缘剂量为16.1 Gy（8 - 24）。放射外科手术后的中位随访期为38.3个月（21 - 67个月）。分析了放射外科手术后出血、癫痫发作和神经功能恶化的发生率，并将出血率与自然病程报告中的出血率进行了比较。
随访期间有1例出血，癫痫发作通过抗惊厥药物得到良好控制。在既往有出血的组中，放射外科手术后海绵状血管畸形的出血率（1.55%/年）低于放射外科手术前（35.5%/年，t = 1.296，P = 0.04）。6例患者放射外科手术后出现神经功能恶化，然而，只有2例接受LINAC治疗的患者神经功能缺损持续存在。放射外科手术方式（LINAC与GK）与辐射诱导的神经功能缺损可能存在相关性（P = 0.06）。在最后一次随访的MR图像上，11例患者的病变缩小，1例增大，10例无变化。T2加权MR图像显示9例患者病变周围有高信号改变。这种信号改变与病变大小（P = 0.236）、位置（P = 0.658）和辐射剂量（P = 0.363）均无统计学相关性，但取决于治疗方式（P = 0.02）。随访期间分别有1例发现新的强化病变和1例发现新的囊肿。
放射外科手术可能是治疗手术风险高的CMs的一个很好的替代选择。然而，最佳的放射外科技术、剂量调整和肿块的正确勾画是先决条件。放射外科手术引起的并发症仍然存在问题，放射外科手术后MR图像的变化需要进一步阐明。
