Brachytherapy of Vestibular Schwannomas: Report of Three Cases

Abstract

Objective: Gamma knife and multileaf collimator LINAC have recently gained notority in the treatment of vestibular schwannomas. Without the use of gamma knife or LINAC, we have successfully pursued the 125-iodine interstitial irradiation of three vestibular schwannomas.

Case Report: Up to March 2004, there was a 57 and 45 month follow-up period in two cases. One patient died of heart insufficiency 15 months after the brachytherapy. At the end of the follow-up period audiometric examinations revealed slight improvements of hearing in patients 1 and 2. In patient 1, the tumor volume measured was 4.06 mL on the control CT indicating a 40 % shrinkage in comparison to the 6.74 mL target volume at the brachytherapy. In patient 2, the tumor volume measured on the control MRI was 6.64 mL, indicating a 42 % shrinkage of the 11.45 mL target volume at the time of brachytherapy. Eleven months after the brachytherapy in patient 3 we found 10 % tumor shrinkage, a post-irradiation cyst developed inside the tumor and reached up to 35 % of the tumor volume.

Intervention: In the treatment of three vestibular schwannomas we have used CT and image-fusion guided 125-iodine stereotactic brachytherapy.

Conclusion: Due to financial considerations, gamma knife and LINAC are not available for many countries and neurosurgical institutes. In the absence of the above-mentioned radiosurgical methods, we have shown brachytherapy as a new alternative and solution in the treatment of the three patients studied with vestibular schwannoma.

Key words

Brachytherapy - image fusion - vestibular schwannoma

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