CLINICAL ARTICLE - NEUROSURGICAL TECHNIQUES Combined endonasal and sublabial endoscopic transmaxillary approach to the pterygopalatine fossa and orbital apex Maysam Alimohamadi 1,2 & Mohamadreza Hajiabadi 1,2 & Venelin Gerganov 1 & Rudolf Fahlbusch 1 & Madjid Samii 1 Received: 23 December 2014 /Accepted: 16 March 2015 # Springer-Verlag Wien 2015 Abstract Background The pterygopalatine fossa (PPF) and inferomedial orbital apex are difficult regions for open neuro- surgical access. The traditional extensive anterior approach (transfacial or transmandibular) and lateral/posterolateral (transcranial) approach were used to access the PPF. The com- bined endonasal and sublabial transmaxillary approach is a less invasive access route for these lesions. In this study, we present the technical and clinical details of our experience with the combined endoscopic endonasal and transmaxillary approach. Methods A retrospective analysis of our patients operated on using a combined endoscopic endonasal and transmaxillary approach was done. The preoperative, intraoperative and post- operative images and all the clinical data were evaluated. The accessibility to the area and extent of surgical resection were reviewed. The surgery-related complications and postopera- tive morbidities were analyzed. The main items of interest were the exposure of the target area and possibility for safe removal. Results Five patients with pathologies located in the area of the PPF and orbital apex were operated on using the combined endoscopic sublabial and endonasal transmaxillary approach. The technique provided sufficient exposure of the area and allowed for safe removal of the preoperatively determined target in all of the patients. One patient developed dry eye and a neurotrophic corneal ulcer, and another patient devel- oped temporary postoperative facial numbness. In the follow- up, only one patient with skull base chordoma had an asymp- tomatic tumor regrowth. The other patients had no recurrence or regrowth. Conclusions The combined endoscopic sublabial and endonasal transmaxillary approach is a safe and effective method for resection of lesions in the PPF and inferomedial orbital apex. Keywords Skull base . Endoscopic . Infratemporal fossa . Orbital apex . Pterygopalatine fossa . Sublabial . Transmaxillary Introduction The pterygopalatine fossa (PPF) and inferomedial orbital apex are difficult regions for open neurosurgical access. The PPF is an inverted quadrangular pyramid-shaped space that extends from the middle cranial fossa to facial skull. This small cavity communicates with the middle cranial fossa, orbit, nasal and oral cavities through six foramina and canals that contain im- portant neurovascular structures [29, 39]. The orbital apex borders the junction of the superior and lateral walls of the most anterior part of the sphenoid sinus cavity posteromedially and continues laterally to the the posterior ethmoidal air cells. Varying degrees of pneumatization of the anterior clinoid process, posterior ethmoidal air cells and sphenoid sinus affect the surgical access to the medial orbital apex and optic canal [1]. Traditionally extensive anterior (transfacial or transmandibular) and lateral/posterolateral (transcranial) ap- proaches have been used to access the PPF. The Lefort I osteotomy and Fisch A to C series of surgical approaches * Maysam Alimohamadi alimohamadi59@gmail.com 1 International Neuroscience Institute, Rudolf Pichlmayr Street, No. 4, 30625 Hannover, Germany 2 Iranian International Neuroscience Institute, Tehran University of Medical Sciences (TUMS), Tehran, Iran Acta Neurochir DOI 10.1007/s00701-015-2402-z