LABORATORY INVESTIGATION J Neurosurg 127:622–629, 2017 L esions in the cavernous sinus were long considered inoperable because of the risk of bleeding from the venous plexus or injury to important neurovascular structures such as the internal carotid artery and the cra- nial and sympathetic nerves. Even in experienced hands, surgery in this region is associated with signifcant mor - bidity. 1,9,37 Pioneering surgeons such as Parkinson, 38–41 Dolenc, 15–18 and Hakuba 25–28,35,36 have paved the way for a greater multidimensional understanding of the anatomy of the cavernous sinus, with the result that this previously inac- cessible region is no longer a “no-man’s land.” Using Do- lenc’s technique, tumors in this location can be resected safely without entering the cavernous sinus neurovascular ABBREVIATIONS MOB = meningo-orbital band; SOF = superior orbital fissure. SUBMITTED February 29, 2016. ACCEPTED August 5, 2016. INCLUDE WHEN CITING Published online November 18, 2016; DOI: 10.3171/2016.8.JNS16465. Endoscopic transorbital route to the cavernous sinus through the meningo-orbital band: a descriptive anatomical study Iacopo Dallan, MD, 1 Alberto Di Somma, MD, 2 Alberto Prats-Galino, MD, PhD, 3 Domenico Solari, MD, PhD, 2 Isam Alobid, MD, 4 Mario Turri-Zanoni, MD, 5 Giacomo Fiacchini, MD, 1 Paolo Castelnuovo, MD, 5 Giuseppe Catapano, MD, 6 and Matteo de Notaris, MD, PhD 6 1 First Otorhinolaryngologic Unit, Azienda Ospedaliero-Universitaria Pisana, Pisa; 2 Division of Neurosurgery, Department of Neurosciences, Reproductive and Odontostomatological Sciences, Universita degli Studi di Napoli Federico II, Naples; 5 Unit of Otorhinolaryngology, Department of Biotechnology and Life Sciences, University of Insubria, Varese; 6 Department of Neuroscience, G. Rummo Hospital, Neurosurgery Operative Unit, Benevento, Italy; 3 Laboratory of Surgical Neuroanatomy (LSNA), Faculty of Medicine, Universitat de Barcelona; and 4 Rhinology and Skull Base Unit, Department of Otorhinolaryngology, Hospital Clínic de Barcelona, Universitat de Barcelona, Spain OBJECTIVE Exposure of the cavernous sinus is technically challenging. The most common surgical approaches use well-known variations of the standard frontotemporal craniotomy. In this paper the authors describe a novel ventral route that enters the lateral wall of the cavernous sinus through an interdural corridor that includes the removal of the greater sphenoid wing via a purely endoscopic transorbital pathway. METHODS Five human cadaveric heads (10 sides) were dissected at the Laboratory of Surgical NeuroAnatomy of the University of Barcelona. To expose the lateral wall of the cavernous sinus, a superior eyelid endoscopic transorbital ap- proach was performed and the anterior portion of the greater sphenoid wing was removed. The meningo-orbital band was exposed as the key starting point for revealing the cavernous sinus and its contents in a minimally invasive interdural fashion. RESULTS This endoscopic transorbital approach, with partial removal of the greater sphenoid wing followed by a “natu- ral” ventral interdural dissection of the meningo-orbital band, allowed exposure of the entire lateral wall of the cavernous sinus up to the plexiform portion of the trigeminal root and the petrous bone posteriorly and the foramen spinosum, with the middle meningeal artery, laterally. CONCLUSIONS The purely endoscopic transorbital approach through the meningo-orbital band provides a direct view of the cavernous sinus through a simple and rapid means of access. Indeed, this interdural pathway lies in the same sagittal plane as the lateral wall of the cavernous sinus. Advantages include a favorable angle of attack, minimal brain retraction, and the possibility for dissection through the interdural space without entering the neurovascular compartment of the cavernous sinus. Surgical series are needed to demonstrate any clinical advantages and disadvantages of this novel route. https://thejns.org/doi/abs/10.3171/2016.8.JNS16465 KEY WORDS cavernous sinus; endoscopic transorbital; superior eyelid transorbital; meningo-orbital band; anatomy ©AANS, 2017 J Neurosurg Volume 127 • September 2017 622 Unauthenticated | Downloaded 09/03/22 10:58 AM UTC