Surgical management of brainstem hydatid cyst--an unusual site.

Background: The authors describe their surgical experience of a hydatid cyst in the brainstem, which is an unusual site. The cyst was internally decompressed and totally excised. Although the Dowling technique has been described to be the ideal method for removal of hydatid cysts, it may not be possible when the cyst is in a deep-seated, vital, and eloquent location. We report the use of internal decompression by aspiration followed by total excision as an alternative method when the cyst is located in vital areas of the brain.

Case Description: A 40-year-old female presented with headache, progressive right-sided weakness, double vision, and unsteadiness of gait of 1-month duration. On examination, she had left one-and-a-half syndrome, right hemiparesis of 3/5, and left cerebellar signs. Computed tomographic and MRI scans of the brain revealed a solitary, stenciled-out cystic lesion in the brainstem more toward the left side with features suggestive of hydatid cyst. A left retromastoid craniectomy followed by left middle cerebellar peduncle approach, aspiration of the cyst, and total excision of the cyst was performed. Postoperatively, the patient improved progressively and was asymptomatic with minimal left cerebellar signs at 1-year follow-up.

Conclusion: Hydatid cyst is a benign lesion. Appropriate management is mandatory for reducing the morbidity. Although the Dowling technique with its modifications is appropriate for cerebral parenchymal surfacing or superficial hydatid cysts, in deep-seated cysts located in eloquent and vital areas such as the brainstem, management by internal decompression by aspiration followed by extirpation of the cyst wall, protecting the surrounding cisterns and CSF spaces, is an alternative option.