OBJECTIVE Tuberculum sellae meningiomas are classically removed through several different surgical transcranial approaches, including the pterional transsylvian route. Recently, the indications for the transsphenoidal technique, traditionally proposed only for the treatment of intrasellar lesions, have been extended to include lesions located in the supra- and parasellar areas and, among them, tuberculum sellae meningiomas. We describe the surgical technique for the purely endoscopic endonasal variant of the extended transsphenoidal "low route" to tuberculum sellae meningiomas. METHODS Over a 22-month period, six patients (three men and three women; mean age, 56.1 yr; age range, 44-70 yr) underwent an extended endoscopic transsphenoidal approach for the treatment of tuberculum sellae meningiomas. Two lesions were less than 2 cm and four were between 2 and 4 cm in size. The details of the surgical technique have been described. RESULTS Gross total removal of the lesion, without the need for brain retraction and with minimal neurovascular manipulation, was achieved in five patients (83.3%), whereas in one patient, only subtotal removal was possible (>90%) because the mass extended into the right optic canal. Four patients with preoperative visual function defects had complete recovery, whereas two patients experienced a temporary worsening of vision. Both of these patients fully recovered within a few days. One patient had a postoperative cerebrospinal fluid leak that required three operations for cranial base defect repair. This patient showed rapid and unexpected worsening with respect to level of consciousness and anisocoria. An intraventricular hemorrhage was discovered, and the patient died 6 days later. Another patient developed new permanent diabetes insipidus that required hormonal replacement therapy. CONCLUSIONS In experienced hands and in carefully selected patients, the extended endoscopic transsphenoidal approach may constitute a viable alternative to transcranial approaches for tuberculum sellae meningioma. At present, the major limits of the approach include the lack of a reliable technique for the reconstruction of a cranial base defect and inadequate follow-up.