Telecanthus

Telecanthus

Diagram illustrating dystopia canthorum, a condition related to telecanthus.

Telecanthus is a medical condition characterized by an increased distance between the medial canthi of the eyes, with a normal interpupillary distance. This condition is often confused with hypertelorism, which involves an increased distance between the bony orbits. Telecanthus is primarily a soft tissue abnormality, whereas hypertelorism is a bony abnormality.

Anatomy and Pathophysiology

The medial canthi are the corners of the eyes where the upper and lower eyelids meet near the nose. In telecanthus, the increased distance between these points is due to an abnormality in the soft tissues, particularly the medial canthal tendon. This can result in a characteristic appearance where the eyes appear to be spaced further apart than normal, despite the bony orbits being correctly positioned.

Causes

Telecanthus can be congenital or acquired. Congenital telecanthus is often associated with genetic syndromes such as Waardenburg syndrome, Down syndrome, and Noonan syndrome. Acquired telecanthus can result from trauma, surgery, or other conditions affecting the medial canthal region.

Congenital Causes

• Waardenburg syndrome: A genetic disorder characterized by varying degrees of deafness, minor defects in structures arising from the neural crest, and pigmentation changes.
• Down syndrome: A genetic disorder caused by the presence of all or part of a third copy of chromosome 21.
• Noonan syndrome: A genetic disorder that causes abnormal development in various parts of the body.

Acquired Causes

• Trauma: Injury to the medial canthal region can disrupt the normal anatomy and lead to telecanthus.
• Surgical complications: Procedures involving the nasal bridge or eyelids can sometimes result in telecanthus if the medial canthal tendon is affected.

Diagnosis

Diagnosis of telecanthus involves clinical examination and measurement of the intercanthal distance. The normal intercanthal distance varies with age and ethnicity, but it is generally considered to be around 30-34 mm in adults. An increased intercanthal distance with a normal interpupillary distance suggests telecanthus.

Treatment

Treatment of telecanthus depends on the underlying cause and the severity of the condition. In cases where telecanthus is part of a syndrome, management of the syndrome as a whole is necessary. Surgical correction may be considered for cosmetic reasons or if the condition affects vision.

Related pages

• Hypertelorism
• Waardenburg syndrome
• Down syndrome
• Noonan syndrome