2. DEFINITION
PTERYGIUM is a triangular encroachment of the vascularized granulation
tissue covered by conjunctiva in the interpalpebral area.
It is the degenerative condition of the conjunctiva.
3. ETIOLOGY
Pterygium is a response to prolonged effect of environmental factors such as:
• Exposure to sun (ultraviolet rays)
• Dry heat
• High wind
• Abundance of dust
4. PATHOGENESIS
Pterygium is degenerative and hyperplastic condition of conjunctiva.
The subconjunctival tissue undergoes elastotic degeneration and proliferates
as vascularised granulation tissue under the epithelium.
It ultimately encroaches the cornea.
It destroys the superficial layers of stroma and bowman’s membrane.
Formation of dense fibrous tissue leads to development of corneal
astigmatism.
5. CLINICAL FEATURES
(1) DEMOGRAPHY:
• Age: Usually common in old age.
• Sex: more common in males doing outdoor work than females.
• It is usually bilateral and more common on nasal side.
6. CLINICAL FEATURES
(2) SYMPTOMS:
• Foreign body sensation
• Irritation
• Diminution of vision as it encroaches the pupillary region of cornea and due to
corneal astigmatism.
• Cosmetic intolerance
• Diplopia
7. CLINICAL FEATURES
(3) SIGNS:
• Triangular fold of conjunctiva encroaching the cornea.
• Parts of fully developed pterygium are:
Head- Apical part present on the cornea.
Neck- Constricted part present in the limbal area.
Body- Scleral part extending between the limbus and canthus.
Cap- Semilunar whitish infiltrate just present in front of the head.
9. TREATMENT
SURGICAL: Indications for surgery-
• Cosmetic disfigurement
• Recurrent irritation, redness & watering
• Visual impairment
• Continued progression threatening to encroach onto the pupillary area
• Diplopia due to interference in ocular movements
• Motility restriction
• Suspected associated neoplastic degeneration
10. SURGICAL METHODS
Surgical excision with free conjunctival limbal autograft(CLAU)
Surgical excision with amniotic membrane graft and mitomycin-C (MMC)
Surgical excision with lamellar keratectomy and lamellar keratoplasty
11. PREOPERATIVE MANAGEMENT
A detailed history is taken and slit lamp examination done preoperatively and
appropriate grading should be done
Past history of similar complain should be noted
History of recurrence is asked as there is a risk of fibrosis due to previous
surgery
Occupation history should be noted
Acute inflammed condition should be ruled out and managed medically first
and the patient should be advised for surgery in follow up
12. PREOPERATIVE MANAGEMENT
Blood pressure
Routine blood investigations
CBC
RBS
Urine – R & M
HIV & HBsAg
Antiplatelet medication should be stopped as per physician & anesthetist
advice
Obtain an informed & written consent
13. Anesthesia
The surgery can be done under local anesthesia – Peribulbar block or can also
be done under topical anesthesia if the patient is cooperative
Anesthetist should be stand by if the patient is having any cardio-respiratory
or any other systemic abnormality
14. Procedure
After anesthesia is given, painting and draping of the affected eye is done
Head of the pterygium is avulsed from the cornea in a centrifugal manner
Corneal scrapping done with 15 no. knife or crescent knife
16. Procedure
Conjunctival autograft is taken from the superior aspect or the
superotemporal aspect
Conjunctival autograft is rotated and placed on the bare sclera
17. Procedure
The graft is sutured with the conjunctiva with vicryl 8-0/9-0 suture
Double pad bandage done with antibiotic moxifloxacin & CMC(0.5%) eye drops
18. Procedure
If the surgery is done with fibrin glue – then the preparation of the glue
should be done prior to surgery
The refrigerated components of the glue are allowed to settle at normal room
temperature 30 mins prior to surgery or put in a lukewarm saline for 20-30 min
The component A & B are prepared under aseptic precaution in different syringes
indicated as per the manufacturer
Both syringes should be marked accordingly & put in the trolley prior to surgery
The Component A & B should be applied over the bare sclera one after the
another and then the CAG is placed over the sclera within 5-10 seconds
Double pad bandage is done without any topical medications
19. Procedure
The amniotic membrane should also be used in stead of CAG & topical
mitomycin – C is advised to prevent the recurrence
20. Complications
Intraoperative
Puncture wound in the body of pterygium while dissecting the Tenon’s tissue
Injury to the medial rectus due to over dissection of the Tenon’s tissue
Injury to the superior rectus while taking the CAG superiorly
Injury to the cornea while scrapping
21. Complications
Postoperative
Displacement of the graft from the original position
Extensive subconjunctival haemorrhage due to poor handling of tissue during surgery
Graft oedema
Granuloma formation
Scleritis
Persistent epithelial defect
Dellen
Endophthalmitis
Late postoperative
Opacification over cornea
Recurrence
