Lateral transpeduncular approach to intrinsic lesions of the rostral pons. 
We describe the lateral transpeduncular approach to access lesions in the rostral pons.  The surgical indications and technique are discussed in the context of an illustrative case and pertinent anatomic considerations.  A 38-year-old man with acute right hemiparesis and bulbar symptoms had a left pontine hemorrhage with an associated cavernous malformation and venous anomaly.  There was no pial or ependymal representation of the lesion.  To avoid disruption of eloquent structures, the pia was entered in the posterolateral aspect of the middle cerebellar peduncle.  Subsequent dissection was guided by stereotactic neuronavigation in a ventromedial trajectory along the course of the pontocerebellar fibers.  The cavernous malformation was resected completely without procedure-related morbidity.  The patient's preoperative deficits slowly improved to a functionally independent state.  The lateral transpeduncular approach may be used to access intrinsic lesions of the rostral pons with relatively low morbidity.  Stereotactic neuronavigation and intraoperative electrophysiological monitoring are important surgical adjuncts to guide dissection and lesion extirpation.  Candidate selection, microsurgical technique, and pragmatic treatment goals remain fundamental to optimal patient outcomes.