射波刀分次治疗海绵窦血管瘤的初步结果

Cyberknife radiosurgery for cavernous sinus hemangiomas： a preliminary outcome

目的总结射波刀分次治疗海绵窦血管瘤（CSH）的初步经验。方法应用射波刀治疗海绵窦血管瘤20例，肿瘤最大径为23．0～67．0mm，平均42．0mm。肿瘤平均体积为25．4cm3。1例肿瘤照射1次，3例照射2次，其余16例肿瘤照射3次，周边剂量分别为13Gy／1次；17．8～19．0Gy／2次；18．4—21．0Gy／3次。随访时间为7—36个月（平均15个月）。结果5例巨大肿瘤射波刀治疗后有轻微的症状加重，需要脱水治疗。所有患者均未出现新的脑神经受损症状。4例视力受影响者治疗后6个月改善，12例其他脑神经受损者症状改善或恢复正常。4例肿瘤缩小90％以上，9例缩小50％以上，4例缩小30％左右，1例未缩小，2例未复查MRI，但是症状改善。结论射波刀治疗CSH的不良反应轻，初步疗效满意。对大型或巨大CSH，射波刀分次照射可成为其主要治疗手段之一。

Objective Cavernous sinus hemangiomas （CSH）are rare vascular tumors. Gamma knife radiosurgery is proved to be effective treatment for CSH. The authors described their experience using fractionated cyberknife radiosurgery for large or giant cavernous sinus hemangiomas. Methods Twenty patients with CSH,including 13 females and 7 males patients with a mean age of 57 years （range： 32 -80 years）, underwent cyberknife radiosurgery. Nineteen patients were diagnosed as CSH based on MRI findings and one patient had a recurrent tumor post surgery. The patients presented with slight headache, ptosis of the eyelid, proptosis, diplopia, facial numbness and visual impairment. On MRI T2 -weighted and Flair images, marked homogeneous hyperintensity were found in all lesions. This is the characteristics of CSH on MRI. Tumor maximum diameter ranged from 23.0 to 67. 0 ram, with a mean of 42.0 mm and the mean tumor volume was 25.4 cm3 （ volume range ： 2. 9 - 96. 2 cm3 ）. Sixteen tumor margin dose irradiated by cyberknife ranged from 18.4 -21.0 Gy（ maximum dose： 28 -30 Gy） in 3 fractions, 3 tumor margin dose was 17.8 - 19. 0 Gy （ maximum dose：27. 8 ~ 29. 2 Gy） in 2 fractions, 1 tumor margin dose was 13 Gy （maximum dose： 20 Gy） in 1 fractiion. Follow -up time was 7 -36 months with a mean of 15 months. Results Five patients with giant CSH had slight headache after finishing cyberknife radiosurgery, and relieved after mannitol and dexamethasone treatment. Follow - up imaging demonstrated tumor decreased more than 90% in volume in 4 patients, more than 50% in volume in 9 patients, about 30% in volume in four patients post cyberknife. One tumor kept stable at 7 months post eyberknife. One patient with giant tumor did not have MRI examination although her symptoms was relieved post cyberknife. 1 patient did not have MRI examination because of short follow - up time. Neurologically, slight headache, ptosis of the eyelid and diplopia in patients without open surgery had improved or disappeared at 4 to 10 months post cyberknife. None of these patients showed any deterioration in symptoms post radiosurgery. No brain edema happened and no cranial nerve deficits developed post cyberknife although most of these tumors were large or giant. Four patients had improvement in visual acuity 6 months post cyberknife, although optic nerve received 16 - 19 Gy in 3 fractions. Conclusion Fractionated Cyberknife radiosurgery is safe and effective modality for small - and medium - sized CSH and proved to be an effective treatment for large or giant CSH. Our experience demonstrated that cyberknife radiosurgery would be a better option for patients who have a clear neuroimaging diagnosis of CSH.