title: Microsurgical anatomy of the orbit: the rule of seven.
abstract: The orbits are paired structures, located on the anterior part of the face. Morphologically, each orbit is a four sided pyramid with a posterior apex and anterior base. In the orbit, all openings are arranged around the base, apex or between the orbital walls. An anatomical characteristic of the orbit is that structures are arranged in groups of seven: there are seven bones, seven intraorbital muscles and seven nerves in the orbit. Tumors confined within the periorbita in the anterior two thirds of the orbit can often be approached extracranially, but those located in the apical area, and especially those on the medial side of the optic nerve, often require a transcranial approach. Thus, knowledge of orbital osteology is paramount in adequately choosing and performing an orbital approach. Understanding the critical topographical elements in this area helps to classify an orbital lesion and provides for a solid basis in choosing the most adequate intraorbital route for its treatment.
authors.affiliation: Medical School of Pernambuco, IMIP, 1393 Recife, PE, Brazil.
authors.forename: Carolina
authors.initials: C
authors.lastname: Martins
authors.forename: Isabel Eugênia
authors.initials: IE
authors.lastname: Costa E Silva
authors.forename: Alvaro
authors.initials: A
authors.lastname: Campero
authors.forename: Alexandre
authors.initials: A
authors.lastname: Yasuda
authors.forename: Luiz Roberto
authors.initials: LR
authors.lastname: Aguiar
authors.forename: Marcos
authors.initials: M
authors.lastname: Tatagiba
authors.forename: Albert
authors.initials: A
authors.lastname: Rhoton