Doppler-sonographically guided resection of central nervous system hemangioblastomas.

BACKGROUND

Central nervous system (CNS) hemangioblastomas are a benign condition, which can be permanently cured by complete surgical removal. However, the vascular nature of these lesions and difficulties in localizing the tumors account for operative morbidity and recurrence. Power Doppler flow sonography has been proven useful during surgical removal of other vascular lesions.

OBJECTIVE

To evaluate the usefulness of Power Doppler flow sonography for hemangioblastoma.

METHODS

We used the SonoWand Invite (Sonowand AS, Trondheim, Norway) intraoperative navigation system in a consecutive series of hemangioblastomas operated on at our institution. Patients with von Hippel-Lindau (VHL) disease as well as sporadic hemangioblastomas were included.

RESULTS

The system was used on n = 64 consecutive hemangioblastomas operated on at our institution from 2007 to 2009. The tumors were localized in the cerebellum (n = 26), spinal cord (n = 27), brainstem (n = 10), and supratentorial (n = 1). In VHL disease was diagnosed 53 patients, and germline mutations of the VHL tumor suppressor gene were identified in 98%. Average tumor size was 1782 mm and 45% of the tumors were cystic. Forty-two of 64 tumors could be localized by grayscale sonography. All tumors were visible on power Doppler flow sonography. However, in 40 cases, only the pathological vessels and not the solid tumor itself enhanced on power Doppler. Postoperative MRI follow-up revealed remnant/recurrent tumors in 2 cases.

CONCLUSION

Power Doppler flow sonography is a sensitive intraoperative tool to guide the surgical approach and resection and provides reliable resection control in surgery of CNS hemangioblastoma.