optic fissure

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Related to optic fissure: Pterygomaxillary fissure

retinal fissure

a ventral groove formed by invagination of the optic cup and its stalk by vascular mesenchyme from which the hyaloid vessels develop.

optic fissure

ret·i·nal fis·sure

(ret'i-năl fish'ŭr)
A ventral groove formed by invagination of the optic cup and its stalk by vascular mesenchyme, from which the hyaloid vessels develop.
Synonym(s): choroid fissure, optic fissure.


1. a narrow slit or cleft, especially one of the deeper or more constant furrows separating the gyri of the brain.
2. in dermatology a deep crack in the skin, often through a scab, which penetrates into the subcutis.

abdominal fissure
a congenital cleft in the abdominal wall.
anal fissure, fissure in ano
a painful linear ulcer at the margin of the anus.
fissure of Bichat
transverse fissure (2).
branchial fissure
branchial cleft.
central fissure
fissure of Rolando.
collateral fissure
a longitudinal fissure on the ventral surface of the cerebral hemisphere between the fusiform gyrus and the hippocampal gyrus.
dorsal median fissure
1. a shallow vertical groove in the closed part of the medulla oblongata, continuous with the dorsal median sulcus of the spinal cord.
2. a shallow vertical groove dividing the spinal cord throughout its whole length in the midline dorsally. Called also dorsal median sulcus.
ear fissure
a split in the margin of the pinna which can gradually become larger from continued trauma.
hippocampal fissure
one extending from the splenium of the corpus callosum almost to the tip of the temporal lobe; called also hippocampal sulcus.
interhemispheric fissure
the fissure between the two cerebral hemispheres in birds.
interincisive fissure
fissure between the two incisive bones at the rostral end of the pig's face.
laryngeal fissure
the dorsal laryngeal furrow.
ligamentum teres fissure
on the diaphragmatic surface of the liver; houses the ligamentum teres.
fissure lines
in radiology, the variation in radiodensity indicating the division between lobes of the lung.
longitudinal fissure
the deep fissure between the cerebral hemispheres.
macropalpebral fissure
an enlarged palpebral fissure.
optic fissure
a ventral fissure in the developing optic cup through which blood vessels pass to the enclosed mesenchyme.
orbital fissure
see orbital foramen.
palatine fissure
a pair of fissures perforating the rostral extremity of the palate.
palpebral fissure
the opening between the eyelids.
perianal fissure
see perianal fistula.
petrotympanic fissure
the chorda tympani, on its way to merge with the lingual branch of the mandibular nerve, passes across the tympanic cavity and emerges at the petrotympanic fissure.
portal fissure
porta hepatis.
presylvian fissure
the ventral branch of the fissure of Sylvius.
reverse fissure
mediastinal fluid dissects into fissures between lung lobes causing fissure lines on radiographs to appear wide centrally and narrower peripherally.
Rolando's fissure, fissure of Rolando
a groove running obliquely across the superolateral surface of the cerebral hemisphere, separating the frontal from the parietal lobe. Called also central fissure and central sulcus.
round ligament fissure
one on the visceral surface of the liver, lodging the round ligament in the adult.
sylvian fissure, fissure of Sylvius
one extending laterally between the temporal and frontal lobes, and turning dorsally between the temporal and parietal lobes of the brain.
transverse fissure
1. porta hepatis.
2. the transverse cerebral fissure between the diencephalon and the cerebral hemispheres; called also fissure of Bichat.
tympano-occipital fissure
on the ventral surface of the skull, near the confluence of the osseous bulla and the occipital bone, this pair of fissures serve as conduits for the glossopharyngeal, vagal and accessory nerves in species without a jugular foramen.
ventral median fissure
a longitudinal furrow along the midline of the ventral surface of the spinal cord and medulla oblongata.
zygal fissure
a cerebral fissure consisting of two branches connected by a stem.