The absence of the eye will cause a small bony orbit, a constricted mucosal socket, short eyelids, reduced palpebral fissure and malar prominence. Genetic mutations, chromosomal abnormalities, and prenatal environment can all cause anophthalmia. Anophthalmia is an extremely rare disease and is mostly rooted in genetic abnormalities. It can also be associated with other syndromes. The most genetic based cause for anophthalmia is caused by the SOX2 gene. Sox2 anophthalmia syndrome is caused by a mutation in the Sox2 gene that does not allow it to produce the Sox2 protein that regulates the activity of other genes by binding to certain regions of DNA.
The corneal reflex, also known as the blink reflex, is an involuntary blinking of the eyelids elicited by stimulation of the cornea (such as by touching or by a foreign body), though could result from any peripheral stimulus. Stimulation should elicit both a direct and consensual response (response of the opposite eye). The reflex occurs at a rapid rate of 0.1 seconds. The purpose of this reflex is to protect the eyes from foreign bodies and bright lights (the latter known as the optical reflex). The blink reflex also occurs when sounds greater than 40–60 dB are made. The reflex is mediated by: Use of contact lenses may diminish or abolish the testing of this reflex.
List of ICD-9 codes 740-759: Congenital anomalies
Congenital anomalies of eyelids, lacrimal system, and orbit. Congenital anomalies of ear, face, and neck. Anomalies of ear causing impairment of hearing. Accessory auricle. Other specified congenital anomalies of ear. Macrotia. Microtia. Unspecified congenital anomaly of ear. Branchial cleft cyst or fistula; preauricular sinus. Webbing of neck. Other specified congenital anomalies of face and neck. Macrocheilia. Microcheilia. Macrostomia. Microstomia. Bulbus cordis anomalies and anomalies of cardiac septal closure. Common truncus. Transposition of great vessels. Tetralogy of fallot. Common ventricle. Ventricular septal defect. Atrial septal defect. Endocardial cushion defects.
Ptosis (eyelid). Blepharospasm. Apraxia. Myokymia.
Tarsorrhaphy is a surgical procedure in which the eyelids are partially sewn together to narrow the eyelid opening. It may be done to protect the cornea in cases of corneal exposure, as a treatment for Graves' ophthalmopathy, Möbius syndrome or after corneal graft surgery. The procedure is performed on the corner of the eyelid opening. * Surgery Encyclopedia: Tarsorrhaphy Eye surgery. Keratoconjunctivitis sicca.
One special detail about adipose eyelids is their ability to filter out specific wavelengths of light. For example, different fish have a different concentration of epithelial tissue in their eyelids. However, there is a range that most of the eyelids will filter. Most adipose eyelids can filter out light that has a wavelength shorter than 305 nanometers. Another fact is that these eyelids can also reflect light and this level of reflection corresponds to polarization of the light and the angle at which it is shone. To test for these ranges, different fish eyelids were exposed to light generated from photometers and polarizing microscopes.
clawed frogAfrican Clawed Frog (Toad)frog
They have no moveable eyelids, tongues (rather it is completely attached to the floor of the mouth ) or eardrums (similarly to Pipa pipa, the common Suriname toad ). Unlike most amphibians, they have no haptoglobin in their blood. Xenopus species are entirely aquatic, though they have been observed migrating on land to nearby bodies of water during times of drought or in heavy rain. They are usually found in lakes, rivers, swamps, potholes in streams, and man-made reservoirs. Adult frogs are usually both predators and scavengers, and since their tongues are unusable, the frogs use their small fore limbs to aid in the feeding process.
Euoplocephalus tutusPaul PenkalskiStereocephalus
The palpebral bones over the eyes may have provided additional protection for the eyes. Such bones with Euoplocephalus have been discovered in the upper part of the eye socket, instead of in front of the upper socket rim which is the more common position. Coombs explained this by assuming that these bones were located in the eyelid musculature and were probably mobile enough to be moved over the eyes. The tail club of ankylosaurids has often been interpreted as a defensive weapon. In Euoplocephalus, the presence of ossified tendons only with the distal half of the tail may support such a function.
punctapuncta lacrimalialacrimal puncta
The lacrimal punctum (plural puncta) or lacrimal point, is a minute opening on the summits of the lacrimal papillae, seen on the margins of the eyelids at the lateral extremity of the lacrimal lake. There are two lacrimal puncta in the medial (inside) portion of each eyelid. Together, they function to collect tears produced by the lacrimal glands. The fluid is conveyed through the lacrimal canaliculi to the lacrimal sac, and thence via the nasolacrimal duct to the inferior nasal meatus of the nasal passage. * Diagram and discussion at aafp.org Imperforate lacrimal punctum. Lacrimal apparatus. Punctal plug.