title: Stereotactic radiosurgery for trigeminal schwannoma: a clinical retrospective study in 52 cases.
abstract: OBJECTIVE
  To evaluate the radiological and clinical outcomes in a series of patients in whom stereotactic radiosurgery (SRS) was used to treat trigeminal schwannomas.
  
  
  METHODS
  The records of 52 patients who underwent SRS for trigeminal schwannoma were reviewed using a retrospective study. The median patient age was 47.1 years (range, 18-77); 20 patients (38.5%) had undergone prior tumor resection and 32 (61.5%) underwent radiosurgery on the basis of imaging diagnosis only. The most frequent presenting symptoms were facial numbness (29 patients), jaw weakness (11 patients), facial pain (10 patients) and diplopia (4 patients). Fifty-two cases with solid tumors were mainly solid in 44 cases (84.6%), mostly cystic in 2 cases (3.8%), and cystic and solid mixed in 6 cases (11.5%). Two cases of mostly cystic tumor first underwent stereotactic cystic fluid aspiration and intracavitary irradiation, and then had MRI localization scan again for gamma knife treatment. The mean tumor volume was 7.2 ml (range, 0.5-38.2). The mean prescription radiation dose was 13.9 Gy (range, 11-17), and the mean prescription isodose configuration was 47.9%.
  
  
  RESULTS
  At a mean follow-up of 61 months (range, 12-156), neurological symptoms or signs improved in 35 patients (67.3%), 14 patients (26.9%) had a stable lesion, and worsening of the disease occurred in 2 patients (3.8%). On imaging, the schwannomas almost disappeared in 8 (15.4%), shrank in 32 (61.5%), remained stable in 5 (9.6%), and increased in size in 7 patients (13.5%). Tumor growth control was achieved in 45 (86.5%) of the 52 patients.
  
  
  CONCLUSIONS
  SRS is an effective and minimally invasive management option for patients with residual or newly diagnosed trigeminal schwannomas. The use of SRS to treat trigeminal schwannomas resulted in good tumor control and functional improvement.
authors.affiliation: Department of Neurosurgery, Navy General Hospital of PLA, Beijing, China.
authors.forename: Junzhao
authors.initials: J
authors.lastname: Sun
authors.forename: Jianning
authors.initials: J
authors.lastname: Zhang
authors.forename: Xin
authors.initials: X
authors.lastname: Yu
authors.forename: Shubin
authors.initials: S
authors.lastname: Qi
authors.forename: Yanan
authors.initials: Y
authors.lastname: Du
authors.forename: Weigang
authors.initials: W
authors.lastname: Ni
authors.forename: Yong
authors.initials: Y
authors.lastname: Hu
authors.forename: Zengmin
authors.initials: Z
authors.lastname: Tian
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009442:Neurilemmoma / Q000000981:diagnostic imaging* / Q000601:surgery*; D011859:Radiography; D016634:Radiosurgery / Q000379:methods; D012189:Retrospective Studies; D016896:Treatment Outcome; D014276:Trigeminal Nerve / Q000000981:diagnostic imaging* / Q000601:surgery*; D055815:Young Adult