the real story of the fifth nerve neurinoma: a review of our learning curve about surgical approaches and associated shortcomings

background and importance: our learning curve during two decades of neurosurgical practice has been changed from an abstractive to a more meaningful and conductive state. in cases of fifth nerve neurinoma, pre-operative anatomopathologic diagnosis could lead us to a pre-planned program during and after the surgery to get the safe surgical result. case presentation: representation of two complex fifth nerve neurinoma cases, untoward happenings and the way to manage patient safety. review of literature to find a wise approach for maximum benefit is included here. conclusion: both of our patients have developed iatrogenic unilateral corneal anesthesia, one of them warned of it and the second one not. we have had more problems in the way of preservation of the cornea in the warned case. we have reviewed the factors influencing safe corneal preservation after the operation of fifth nerve neurinoma which are included following items: surgical approach, anatomopathologic location of the tumor (pre-ganglionic, ganglionic or post-ganglionic), simultaneous damage of v and vii nerve including vidian nerve, preserved corneal sensation, any combination of injury to physiologic and mechanical protectors. the cornerstones to have a safe cornea following such surgeries are pre-operative exam of fifth and 7th nerve in all aspects and also early post-operative evaluation of them including the state of the tear secretion. we encounter corneal anesthesia and epithelial defect. iatrogenic damage of vidian nerve depending to approach selected seems to be considerable. simultaneous damage of v and vii nerve during the surgery of large neurinoma are expected and noteworthy.