MATERIAL and METHODS: A frameless armless infrared-based neuronavigation system was applied in the microsurgical removal of 7 orbital tumors. Image guidance was CT-based in 3 cases, MRI-based in another 3 cases and based on image fusion between CT and MRI image sets in one patient. The extradural fronto-orbital approach was performed in 3 cases, lateral orbitotomy in 2 cases, trans-supraciliar approach in 1 case and inferomedial orbitotomy in 1 case.

RESULTS: The surgical procedures were successful in all cases. The procedure-related morbidity and mortality rate in the series was zero. The registration accuracy of the neuronavigation ranged between 1.0 and 1.7 mm, with an average of 1.3 mm. Neuronavigated image guidance was evaluated as useful in all patients. Total tumour removal was achieved in 5 patients and partial tumour excision in 1 case. One patient was only biopsied.

CONCLUSION: Neuronavigation is not a substitute for surgical knowledge and experience, but it is a valuable complement with significant intraoperative potential in cranioorbital surgery. Keywords : Orbital tumours, Neurosurgery, Image-guided neurosurgery, Neuronavigation