The beauty of the world can be felt with all of our 5 senses including sight, taste, touch, smell and sound. The ability to be able to use these senses is often taken for granted until a person loses the ability or the ability becomes diminished due to ageing process and diseases. In medicine, what is normal and what is not of the human body is important to determine if a person does have certain diseases or disorders. In this article, we will be learning about telecanthus and is it normal?
Before going about telecanthus, what exactly is canthus of the eyes? Canthus of the eyes are the corner of the eye where the upper and lower eyelids meet. Telecanthus is defined as an abnormal insertion or length of the medial canthal tendon. In simple words, the increased distance between the inner corners of the eyelids. The medial canthal tendon is associated with medial canthus. Medial canthus is the connection point of the upper and lower lid and the nasal bridge.
Telecanthus can be congenital, which means be present at birth or acquired such as from accidents or trauma. Congenital telecanthus is often associated with Down syndrome, Cri du Chat syndrome, Turner syndrome, Ehlers-Danlos syndrome and Klinefelter syndrome. Acquired telecanthus is often as a result of facial injuries to either lacerated (tear) of medial canthal tendon, avulse (disconnected) of bony attachment around the lacrimal crest or displacement of the nasoorbital (nose and eye) component following a fracture.
The easiest way to know if a person has telecanthus or not, is to make a measurement between the center of the pupil. This is known as the interpupillary distance. The average interpupillary distance is 60-62 millimetres (mm) which corresponds to the intercanthal distance of approximately 30-31 mm. The normal intercanthal distance is less than 20 mm and less than 24 mm in older children. When there is an increased distance between the medial canthus of the eyes with normal interpupillary distance, a person is said to have telecanthus.
In patients with congenital telecanthus, symptoms presenting are cosmetic and even the medial canthal tendons are long, patients rarely complain of tearing. The eyes may appear as esotropic (eye misalignment characterised by inwards turn of one or both eyes). In telecanthus with syndrome, associated finding such as epicanthus (skin fold covering the inner corner of the eye) and ptosis (abnormally low positioned upper eyelids that droops over the eyes), severe hearing impairment, bright colour blue iris or different iris colour of the two eyes can be found. Since there are many syndromes that can be related to telecanthus, it is best to talk with a doctor on the symptoms associated as telecanthus is not the only concern regarding the syndrome. Telecanthus may be one of the features of a rare disease or genetic syndrome in children.
Treatment of telecanthus involves shortening and fixing the medial canthal tendons. The medial canthal tendon will be fixated. The treatment is difficult as there are chances of the loosening of the tendon. A transnasal wiring is the most effective method and frequently used to achieve the highest fixation force. In traumatic telecanthus such as from fractures, apart from the reattachment of the medial canthal tendon, repositioning of the bony fragments is usually done together.
In essence, telecanthus is definitely not normal for a human. When it is present in a child, it could be a sign of an underlying genetic disease or rare diseases. In this case, parents should bring their kids to the doctor for further investigation. The outcome of the treatment for telecanthus varies and surgery often leaves scarring to the medial canthus. Talk to your doctor on what to expect and what to do before and after surgery.
Telecanthus itself does not cause any form of pain or vision problems but the fact that the syndromes associated with it may actually affect the way a person sees as it may cause low vision or near-sightedness. Telecanthus should not be confused with hypertelorism. Hypertelorism is an abnormal increase of the distance between the orbits. The differences between hypertelorism are there is an increase of the interorbital width due to the overgrowth of bone or any bone issues. Hypertelorism also shows an increase in the interpupillary distance which is the opposite of the telecanthus that have normal interpupillary distance. Hypertelorism is considered a birth defect as the eye development of the eye socket fails to rotate into the normal position during the embryo phase of 4 to 8 weeks of pregnancy. Hence, telecanthus is a condition that may exist congenitally or acquired but hypertelorism is certainly a congenital condition.
It is understandable that telecanthus and hypertelorism may be seen as the same issue but it is not. Both required surgery to fix the issues to avoid visual issues in the future and to improve their appearance so that they can be confident in public.