A Suggestion of Modified Classification of Trigeminal Schwannomas According to Location, Shape, and Extension.
10.14791/btrt.2014.2.2.62
- Author:
Seong Kyun JEONG
1
;
Eun Jung LEE
;
Yun Hee HUE
;
Young Hyun CHO
;
Jeong Hoon KIM
;
Chang Jin KIM
Author Information
1. Department of Neurosurgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea. cjkim@amc.seoul.kr
- Publication Type:Original Article
- Keywords:
Classification;
Neurilemmoma;
Surgical procedure;
Trigeminal nerve
- MeSH:
Cerebrospinal Fluid;
Chungcheongnam-do;
Classification*;
Craniotomy;
Female;
Humans;
Male;
Meningitis;
Mortality;
Neurilemmoma*;
Osteotomy;
Recurrence;
Retrospective Studies;
Trigeminal Nerve
- From:Brain Tumor Research and Treatment
2014;2(2):62-68
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND: Comprehensive knowledge of the anatomical features of trigeminal schwannomas (TSs) is essential in planning surgery to achieve complete tumor resection. In the current report, we propose a modified classification of TSs according to their location of origin, shape, and extension into the adjacent compartment, and discuss appropriate surgical strategies with this classification. METHODS: We retrospectively analyzed 49 patients with TS who were treated surgically by a single neurosurgeon at the Asan Medical Center between 1993 and 2013. RESULTS: There were 22 males and 27 females, with the median age of 40 years (range, 21-75 years). Median tumor size was 4.0 cm in diameter (2.0-7.0 cm). Tumors were classified as follows: Type M (confined to the middle fossa; 8 cases, 19.0%), P (confined to the posterior fossa; 2 cases, 4.8%), MP (involving equally both middle and posterior fossae; 5 cases, 11.9%), Mp (predominantly middle fossa with posterior fossa extension; 6 cases, 14.3%), Pm (predominantly posterior fossa with middle fossa extension; 16 cases, 38.1%), Me (predominantly middle fossa with extracranial extension; 4 cases, 9.5%). Surgical approach was chosen depending on the tumor classification. More specifically, a frontotemporal craniotomy and extradural approach with or without zygomatic or orbitozygomatic osteotomy was applied to M- or Mp-type tumors; a lateral suboccipital craniotomy with or without suprameatal approach was applied to the majority of P- or Pm-type tumors; and a posterior transpetrosal approach was used in four tumors (three Pm and one MP). Gross total resection was achieved in 95.9% of patients, and the overall recurrence rate was 4.1% (2 patients). Postoperatively, trigeminal symptoms were improved or unchanged in 51.0% of cases (25 patients). Surgical complications included meningitis (5 patients) and cerebrospinal fluid leakage (3 patients). There was no mortality. CONCLUSION: TSs are well to be classified with our modified classification and able to be removed effectively and safely by selecting appropriate surgical approaches.
