In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. “Orbit” can refer to the bony socket, or it can also be used to imply the contents. In the adult human, the volume of the orbit is 30 millilitres, of which the eye occupies 6.5 ml. The orbital contents comprise the eye, the orbital and retrobulbar fascia, extraocular muscles, cranial nerves II, III, IV, V, and VI, blood vessels, fat, the lacrimal gland with its sac and nasolacrimal duct, the eyelids, medial and lateral palpebral ligaments, check ligaments, the suspensory ligament, septum, ciliary ganglion and short ciliary nerves.
The pterygopalatine ganglion is a parasympathetic ganglion found in the pterygopalatine fossa. It is largely innervated by the greater petrosal nerve ; and its axons project to the lacrimal glands and nasal mucosa. The flow of blood to the nasal mucosa, in particular the venous plexus of the conchae, is regulated by the pterygopalatine ganglion and heats or cools the air in the nose. It is one of four parasympathetic ganglia of the head and neck, the others being the submandibular ganglion, otic ganglion, and ciliary ganglion.
The maxillary nerve (CN V2) is one of the three branches or divisions of the trigeminal nerve, the fifth (V) cranial nerve. It comprises the principal functions of sensation from the maxillary, nasal cavity, sinuses, the palate and subsequently that of the mid-face, and is intermediate, both in position and size, between the ophthalmic nerve and the mandibular nerve.
The greater wing of the sphenoid bone, or alisphenoid, is a bony process of the sphenoid bone; there is one on each side, extending from the side of the body of the sphenoid and curving upward, laterally, and backward.
The pterygomaxillary fissure is a fissure of the human skull. It is vertical, and descends at right angles from the medial end of the inferior orbital fissure. It is a triangular interval, formed by the divergence of the maxilla from the pterygoid process of the sphenoid.
The maxillary artery supplies deep structures of the face. It branches from the external carotid artery just deep to the neck of the mandible.
The sphenopalatine foramen is a foramen in the skull that connects the nasal cavity with the pterygopalatine fossa.
The greater palatine artery is a branch of the descending palatine artery and contributes to the blood supply of the hard palate and nasal septum.
The middle cranial fossa, deeper than the anterior cranial fossa, is narrow medially and widens laterally to the sides of the skull. It is separated from the posterior fossa by the clivus and the petrous crest.
The infratemporal fossa is an irregularly shaped cavity, situated below and medial to the zygomatic arch. It is not fully enclosed by bone in all directions, and it contains superficial muscles that are visible during dissection after removing skin and fascia: namely, the lower part of the temporalis muscle, the lateral pterygoid, and the medial pterygoid.
The pterygoid canal is a passage in the skull leading from just anterior to the foramen lacerum in the middle cranial fossa to the pterygopalatine fossa.
The sphenoidal process of the palatine bone is a thin, compressed plate, much smaller than the orbital, and directed upward and medialward.
The perpendicular plate of palatine bone is the vertical part of the palatine bone, and is thin, of an oblong form, and presents two surfaces and four borders.
In human anatomy of the mouth, the palatine process of maxilla, is a thick, horizontal process of the maxilla. It forms the anterior three quarters of the hard palate, the horizontal plate of the palatine bone making up the rest.
The following outline is provided as an overview of and topical guide to human anatomy:
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Gray's Anatomy is an English language textbook of human anatomy originally written by Henry Gray and illustrated by Henry Vandyke Carter. Earlier editions were called Anatomy: Descriptive and Surgical, Anatomy of the Human Body and Gray's Anatomy: Descriptive and Applied, but the book's name is commonly shortened to, and later editions are titled, Gray's Anatomy. The book is widely regarded as an extremely influential work on the subject, and has continued to be revised and republished from its initial publication in 1858 to the present day. The latest edition of the book, the 41st, was published in September 2015.
