Radiosurgery for Para-IAC Meningiomas: The Effect of Radiation Dose to the Cochlea on Hearing Outcome

Journal Article · Thu Nov 01 00:00:00 EDT 2012 · International Journal of Radiation Oncology, Biology and Physics

DOI:https://doi.org/10.1016/J.IJROBP.2011.12.078· OSTI ID:22149567

Kim, Young-Hoon ^[1]; Han, Jung Ho ^[1]; Chung, Hyun-Tai; Kim, In Kyung; Song, Sang Woo ^[2]; Park, Jeong-Hoon ^[1]; Kim, Jin Wook; Kim, Yong Hwy; Park, Chul-Kee ^[2]; Kim, Chae-Yong ^[1]; Paek, Sun Ha; Jung, Hee-Won ^[2]

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1. Department of Neurosurgery, Seoul National University Bundang Hospital, Seongnam-si (Korea, Republic of)
2. Department of Neurosurgery, Seoul National University Hospital, Seoul (Korea, Republic of)

Purpose: This study was performed to assess the radiosurgical results of meningiomas extending into the internal acoustic canal (para-IAC meningiomas), with a particular focus on the effect of radiation dose to the cochlea on hearing outcome. Methods and Materials: A total of 50 patients who underwent radiosurgery for para-IAC meningiomas between 1998 and 2009, which were followed for 2 years, were enrolled. The mean age was 55.8 years (range, 15-75). The mean tumor volume was 6.1 cm{sup 3} (range, 1.0-19.0), the mean tumor length in the IAC was 6.9 mm (range, 1.3-13.3), and the mean prescribed marginal dose was 13.1 Gy (range, 10-15) at an isodose line of 50%. The mean follow-up duration was 46 months (range, 24-122). Results: Eight (16.0%) patients had nonserviceable hearing at the time of surgery. At the last follow-up, the tumor control rate was 94%; unchanged in 17 patients, decreased in 30 patients, and increased in 3 patients. Among 42 patients with serviceable hearing at the time of radiosurgery, it was preserved in 41 (97.6%) patients at the last follow-up. The maximal and mean radiation doses to the cochleae of these 41 patients were 5.8 Gy {+-} 0.3 (range, 3.1-11.5) and 4.3 Gy {+-} 0.2 (range, 2.2-7.5), respectively. The maximal dose to the cochlea of the patient who lost hearing after radiosurgery was 4.7 Gy. Conclusions: The radiation dose to the cochlea may have the minimal toxic effect on the hearing outcome in patients who undergo radiosurgery for para-IAC meningiomas.

• OSTI ID: 22149567
• Journal Information: International Journal of Radiation Oncology, Biology and Physics, Vol. 84, Issue 3; Other Information: Copyright (c) 2012 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
GY RANGE 10-100
NEOPLASMS
PATIENTS
RADIATION DOSES
RADIOTHERAPY
SURGERY
TOXICITY