Objective To provide a new approach for the treatment of tumor in Meckel's cave, by dissecting adjacent structures of the nasal cavity-maxillary sinus-pterygopalatine fossa-Meckel's cave approach. Methods Fifteen adult cadaver heads (30 sides) were dissected and the correlated anatomic landmarks were observed, measured and analyzed in an operative route. Results The approach was divided into 3 steps: entering the maxillary sinus, the later pterygopalatine fossa and the final Meckel's cave. Safe access to Meckel's cave could be achieved by tracing the vidian neurovascular bundles and dissecting the quadrangular space (QS). The distances from the nasal columella to the apertura maxillaries, the sphenopalatine foramen, and the anterior foramen of the pterygoid canal were (44.08 +/- 2.61) mm, (64.83 +/- 2.42) mm, and (70.43 +/- 2.94) mm, respectively. The angles between the horizontal plate of the palatine bone and the link from nasal columella to apertura maxillaries, between the horizontal plate of the palatine bone and the link from nasal columella to sphenopalatine foramen were (38.10 +/- 2.46)degrees and (26.15 +/- 2.26)degrees, respectively. Conclusion The endoscopic approach of transnasal maxillary sinus-pterygopalatine fossa-Meckel's cave (ENMPA) is a safe and direct way to access Meckel's cave, and could be employed for the treatment of tumor in Meckel's cave.
