Subtemporal keyhole approach to the suprasellar and petroclival region: microanatomic considerations and clinical application.

OBJECTIVE: To minimize surgical invasiveness, the keyhole concept is applied to the subtemporal approach.
METHODS: Anatomic features were studied in 14 sides of adult cadaver heads, and the technique was used in 162 interventions. Although most of the lesions treated were 3 cm in size or smaller, larger lesions were also treated using this technique. In some cases, if needed, an endoscope-assisted microsurgical technique was used.
RESULTS: The cadaveric study provided intimate experience with the microsurgical anatomy of the approach. The 162 consecutive patients who were operated on harbored various types of lesions; the most recent 43 consecutive interventions were investigated in detail. The complications encountered included five cases of permanent cranial nerve palsy, two cases of cerebrospinal leakage, two cases of short memory disturbance, two cases of seizure, and one case each of hemiplegia and incoordination, transient hearing loss and tinnitus, and consciousness deterioration and hemiplegia.
CONCLUSION: With careful patient selection, the subtemporal keyhole approach diminishes tissue traumatization considerably and has proven to provide sufficient operating space in the suprasellar area. When this approach is combined with the cranial base technique, the petroclival region can also be treated. However, the subtemporal keyhole approach requires deliberate preoperative planning for each patient, as well as for each surgeon.