The unilateral occipital transtentorial approach for pineal region meningiomas: a report of 15 cases.

In the current study, we reviewed and re-evaluated the experiences of microsurgical management for pineal region meningiomas via the unilateral occipital transtentorial approach (Poppen's approach). Clinical data were obtained on 15 meningiomas of the pineal region, which underwent microsurgery via unilateral Poppen's approach from March 2009 to June 2012. These patients were hospitalized in our department; their data were collected and analyzed retrospectively. The tumors were removed via the right Poppen's approach in 12 cases and left Poppen's approach in 3 cases, and intraoperative external ventricular drainage was performed for hydrocephalus in 3 cases. As a result, gross total resection was achieved in 11 cases, near total resection in 3 cases and subtotal resection in 1 case. All resected tumors were pathologically confirmed. The postoperative complications included two cases of homonymous hemianopia, and deteriorated Parinaud syndrome and diplopia in one case. Ten cases were followed up (range 1-4 years) and no death occurred. On the basis of the existing literature and our experiences, the unilateral Poppen's approach is appropriate for most meningiomas of the pineal region that are small or intermediate in size. However, gross total resection might be difficult via the unilateral Poppen's approach for large-sized meningiomas with much contralateral infratentorial extension due to limited exposure. For these cases, combined supra-infratentorial or bilateral Poppen's approaches are recommended. Preoperative or intraoperative external ventricular drainage can increase tumor exposure and improve microsurgical effects.