Pterygium (plural ''pterygia'' or ''pterygiums'') refers to any wing-like triangular membrane occurring in the neck, eyes, knees, elbows, ankles or digits. The term comes from the Greek word ''pterygion'' meaning "wing".

Types

Popliteal pterygium syndrome Popliteal pterygium syndrome (PPS) is an heredity, inherited condition affecting the face, Limb (anatomy), limbs, and genitalia. The syndrome goes by a number of names including the ''popliteal web syndrome'' and, more inclusively, the ''facio-geni ...

, a congenital condition affecting the face, limbs, or genitalia but named after the wing-like structural anomaly behind the knee *

Pterygium (eye) A pterygium of the eye (plural ''pterygia'' or ''pterygiums'', also called surfer's eye) is a pinkish, roughly triangular tissue growth of the conjunctiva onto the cornea of the eye. It typically starts on the cornea near the nose. It may slow ...

or surfer's eye, a growth on the

cornea The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber. Along with the anterior chamber and lens, the cornea refracts light, accounting for approximately two-thirds of the eye's total optical power ...

of the eye *

Pterygium colli A webbed neck, or pterygium colli, is a congenital skin fold that runs along the sides of the neck down to the shoulders. There are many variants. Signs and symptoms On babies, webbed neck may look like loose folds of skin on the neck. As the ...

or webbed neck, a congenital skin fold of the neck down to the shoulders *

Pterygium inversum unguis Pterygium inversum unguis or ventral pterygium is characterized by the adherence of the distal portion of the nailbed to the ventral surface of the nail plate.James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Cl ...

or ventral pterygium, adherence of the distal portion of the nailbed to the ventral surface of the nail plate *

Pterygium unguis Pterygium unguis (or dorsal pterygiumFreedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). McGraw-Hill. .) forms as a result of scarring between the proximal nailfold and matrix, with the classic example being liche ...

or dorsal pterygium, scarring between the proximal nail fold and matrix

Pterygium of the eye

A pterygium reduces the vision in several ways: # Distortion of the corneal optics. This begins usually when the pterygium is greater than 2mm from the corneal edge (limbus). # Disruption of the tear film. The tear film is the first lens in the eye. Pterygia are associated with eyelid inflammation, called Blepharitis. # Growth over the corneal centre, which leads to dramatic reduction of vision. # Induced anterior corneal scarring, which often remains after surgical removal. A pterygium of the eye grows very slowly. Usually it takes several years or decades to progress.

Surgical removal

Indications for surgery, in order of decreasing importance: # Growth over the corneal centre. # Reduced vision due to corneal distortion. # Documented growth. # Symptoms of discomfort. # Cosmesis. Surgery is usually performed under local anaesthetic with light sedation as day surgery. The pterygium is stripped carefully off the surface of the eye. If this is all that is done, the pterygium regrows frequently. The technique with the lowest recurrence rate uses an auto graft of conjunctiva from under the eyelid. This is placed over the defect remaining from the removed pterygium. The graft can be stitched in place, which is time-consuming, and painful for the patient afterwards. An alternative is the use of tissue adhesive fibrin glue (Tisseel or Full Link or Beriplast P or Quixil). A Cochrane Review including 14 studies and last updated October 2016, found that using fibrin glue when doing conjunctival autografting was associated with a reduced likelihood of the pterygium recurring compared with sutures. The review found that operations may take less time but fibrin glue may be associated with more complications (for example, rupture, shrinking and inflammation (granuloma). A 3-year clinical study on the application of ologen collagen matrix as excision site grafts showed significantly improved surgery success rates. The mechanism of the collagen matrix graft (commercially available as ologen®) works by promoting healthy cell growth into the matrix, thus preventing conjunctiva overgrowth that can cover the iris.

Types

Pterygium of the eye

Surgical removal

References

Further reading