An extremely giant lumbar schwannoma: new classification (kotil) and mini-open microsurgical resection.

Purely extradural giant lumbar schwannomas are rare lesions. Classification of these tumors is performed according to the sizes and spills and is named the modified Sridhar's classification. The management of these tumors has traditionally been performed by combined antero-posterior large or two-stage exposures. This combined exposure has many disadvantages. Recent reports have demonstrated the safety and efficacy of removal of these tumors using mini-open micro surgical resection for the schwannomas, but the safety and efficacy have not been established for extremely large giant tumors. We report a case of a giant L4 dumb-bell schwannoma successfully resected through a mini-open micro surgical resection. These neoplasms can be safely and effectively treated with mini-open techniques. Reduction in blood loss, hospitalization, and tissue disruption may be potential benefits of this approach. We discuss the technical details of this surgical approach along with the limitations and possible complications. In addition, this study is included in the current schwannoma (Kotil) classification.