In anatomy, a fissure is a groove, natural division, deep furrow, elongated cleft, or tear in various parts of the body also generally called a sulcus, or in the brain a sulcus.
In anatomy, the orbit is the cavity or socket of the skull in which the eye and its appendages are situated. Anatomical term created by Gerard of Cremona. “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 superior orbital fissure is a foramen in the skull, although strictly it is more of a cleft, lying between the lesser and greater wings of the sphenoid bone.
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 calcarine sulcus is an anatomical landmark located at the caudal end of the medial surface of the brain of humans and other primates. Its name comes from the Latin "calcar" meaning "spur". It is a complete sulcus.
The largest and deepest fissure in the cerebellum is named the horizontal fissure.
The lesser wings of the sphenoid or orbito-sphenoids are two thin triangular plates, which arise from the upper and anterior parts of the body, and, projecting lateralward, end in sharp points [Fig. 1].
The medial wall and the floor of the orbit are separated posteriorly by the inferior orbital fissure which transmits the zygomatic branch of the maxillary nerve and the ascending branches from the pterygopalatine ganglion. The infraorbital vessels are found in the inferior orbital fissure, and travel down the infraorbital groove into the infraorbital canal and exit through the infraorbital foramen. Inferior division of ophthalmic vein passes through the inferior orbital fissure.
In human anatomy, the infraorbital foramen is an opening in the maxillary bone of the skull located below the infraorbital margin of the orbit. It transmits the infraorbital artery and vein, and the infraorbital nerve, a branch of the maxillary nerve. It is typically 6.10 to 10.9 mm from the infraorbital margin.
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.
In neuroanatomy, a sulcus is a depression or groove in the cerebral cortex. It surrounds a gyrus, creating the characteristic folded appearance of the brain in humans and other mammals. The larger sulci are usually called fissures.
The mandibular fossa is the depression in the temporal bone that articulates with the mandible. In the temporal bone, the mandibular fossa is bounded anteriorly by the articular tubercle and posteriorly by the tympanic portion of the temporal bone, which separates it from the external acoustic meatus. The fossa is divided into two parts by a narrow slit, the petrotympanic fissure.
The petrotympanic fissure is a fissure in the temporal bone that runs from the temporomandibular joint to the tympanic cavity.
Not to be confused with the inferior orbital fissure, which is just lateral to the infraorbital groove.
The anterior median fissure contains a fold of pia mater, and extends along the entire length of the medulla oblongata: It ends at the lower border of the pons in a small triangular expansion, termed the foramen cecum.
The rhinal cortex is the cortex surrounding the rhinal fissure, including the entorhinal cortex and the perirhinal cortex. It is a cortical region in the medial temporal lobe that is made up of Brodmann areas 28, 34, 35 and 36.
The hippocampal sulcus, also known as the hippocampal fissure, is a sulcus that separates the dentate gyrus from the subiculum and the CA1 field in the hippocampus.
The biventer lobule is a region of the cerebellum. It is triangular in shape; its apex points backward, and is joined by the gray band to the pyramid.
The monticulus of the cerebellum is divided by the primary fissure into an anterior, raised part, the culmen or summit, and a posterior sloped part, the clivus; the quadrangular lobule is similarly divided.
