Sprik C, Wirtschafter J D
Department of Ophthalmology, University of Minnesota Medical School, Minneapolis 55455.
Ophthalmology. 1988 Aug;95(8):1042-5. doi: 10.1016/s0161-6420(88)33044-7.
Hemifacial spasm (HFS) due to intracranial mass lesions is rare. Most cases are thought to be due to compression of the facial nerve by small vessels near the root of the facial nerve. A survey was undertaken of all botulinum toxin investigators to determine the incidence of imaged mass lesions causing HFS. Responders contributed information on 1676 patients with HFS. Of this group, nine tumors were reported for an incidence of 0.54% of patients. However, of this group only 52.5% underwent computed tomography (CT) or magnetic resonance (MR) scanning so the incidence of tumor causing HFS could be as high as 1.0%. No one tumor type was predominant, and most patients were women older than 50 years of age. The incidence compares with another large series of HFS patients in which one tumor was found in 367 patients. The authors also report as an illustrative case a 26-year-old man with HFS due to a presumed lipoma of the cerebellopontine angle. This diagnosis can be made with increased certainty with MR scanning. If the incidence of unsuspected diagnostically significant mass lesions is 1 in 200 patients with HFS referred for botulinum toxin injection, the cost of detecting one such lesion would be $100,000 at an average imaging cost of $500 per MR imaging or CT examination. Although mass lesions are uncommon, any patient with HFS whose general clinical course could justify intervention should be considered for imaging studies to rule out treatable conditions other than vascular compression.
颅内占位性病变所致的半面痉挛（HFS）较为罕见。多数病例被认为是由于面神经根部附近的小血管对面神经的压迫所致。对所有肉毒杆菌毒素研究者进行了一项调查，以确定导致HFS的成像占位性病变的发生率。受访者提供了1676例HFS患者的信息。在这组患者中，报告了9例肿瘤，发生率为患者总数的0.54%。然而，在这组患者中，只有52.5%接受了计算机断层扫描（CT）或磁共振成像（MR）扫描，因此导致HFS的肿瘤发生率可能高达1.0%。没有一种肿瘤类型占主导地位，大多数患者为50岁以上的女性。该发生率与另一组大量HFS患者的情况进行了比较，在那组患者中，367例患者发现了1例肿瘤。作者还报告了一例说明性病例，一名26岁男性因疑似桥小脑角脂肪瘤患有HFS。通过MR扫描可以更确定地做出该诊断。如果在转诊接受肉毒杆菌毒素注射的HFS患者中，未被怀疑的具有诊断意义的占位性病变的发生率为每200例中有1例，那么以每次MR成像或CT检查平均费用500美元计算，检测出一例这样的病变的成本将为10万美元。尽管占位性病变并不常见，但任何HFS患者，只要其总体临床病程表明有必要进行干预，都应考虑进行影像学检查，以排除血管压迫以外的可治疗疾病。
