4. DlhNa ko Anausaar va%ma-gat raogaaoM ko baad Sau@lamaNDla ko raogaaoM ko vaNa-na ka karNa hO ik
SarIr rcanaa kI dRiYT sao va%ma-maNDla ko pScaat Sau@lamaNDla ka sqaana hO.
Aacaaya- sauEaut matanausaar Sau@lagat raoga 11 maanao hOM.
Aacaaya- sauEaut matanausaar Sau@lagat raoga 13 maanao hOM.
va%ma-maNDla ko baad Sau@lamaNDla ko raogaaoM ka vyaa#yaana hO.
17. The word Pterygium is derived from the Latin word,
“Pterygos”
which means a wing .
Pterygium is a common ocular surface lesion characterized by a wing
shaped fibrovascular fold of bulbar conjunctiva which encroaches upon the
cornea.
Also known as ‘SURFER’s EYE’.
18. ETIOLOGY
The etiology of pterygium is still unknown. But there
are various theories that are proposed that contributes
to the development of pterygium which includes:-
• Point mutations of proto-oncogenes K-ras.
Alterations in the expression of tumor suppressor
genes as p53/p63
• UV radiations--- exposure to these rays results into
induction of mediators for growth of pterygium.
It is called ‘TWO HIT’ Mechanism.
The first hit is the process of tumor suppressor gene
deactivation.
The second hit is the environmental factors that
includes viral infection or the exposure of UV
radiations.
19. PATHOLOGY
Pathologically pterygium is a degenerative and hyperplastic condition
of conjunctiva.
The subconjunctival tissue undergoes elastic degeneration and
proliferates as vascularized granulation tissue under the epithelium,
which ultimately encroaches the cornea.
The corneal epithelium, Bowman's layer and superficial stroma are
destroyed.
20. PARTS OF PTERYGIUM
It consists of 3 parts :-
Head :- present on cornea (apical part ).
Neck :- narrow part near limbus (limbal part).
Body :- extending between limbus and canthus
(scleral part).
Stocker’s Line
A Stocker line is the brown iron line in the cornea
anterior to the head of the pterygium.
21. TYPES OF PTERYGIUM
Depending upon the progression it may be of 2 types:
Progressive pterygium is thick, fleshy and
vascular with a few infiltrates in the cornea, in
front of the head of the pterygium (called cap of
pterygium).
Regressive pterygium is thin, atrophic,
attenuated with very little vascularity. There is no
cap. Ultimately it becomes membranous but never
disappears.
22. SYMPTOMS & SIGNS
1. It is usually asymptomic.
2. There is cosmetic disfigurement.
3. Visual disturbances occur when it encro
aches the papillary area .
4. Occasionally diplopia due to limitation
of ocular movement .
5. Other symptoms includes:-
Discomfort
Foreign body sensation
Congestion
SYMPTOMS
Triangular encroachment of
conjunctiva on the cornea .
Numerous small opacities may
lie in front of apex of pterygium.
SIGNS
24. GRADING OF PTERYGIUM
Clinical Grading
GRADE 1: extends 2mm on the cornea
GRADE 2: involves upto 4 mm of the cornea it can be
primary or secondary.
GRADE 3: encroaches more than 4mm of the cornea
&it can hamper visual axis.
Tan’s Classification
T1 GRADE: clearly visible episcleral vessels under the
pterygium
T2 GRADE: partially visibility of the episcleral vessels
under the pterygium.
T3 GRADE: total obscured view of the episcleral
vessels under the pterygium.
27. DIFFERENTIAL DIAGNOSIS
CHARACTERS PTERYGIUM PSEUDOPTERYGIUM
AGE More common in older age
groups
Maybe seen in anygroup
SITE 3’oclock to 9’oclock meri
dians
Mayappear anywhereon the
cornea
LATERALITY bilateral Mostly unilateral
STAGES Progressive,reggresiveor stat
ionary
Always stationary
ETIOLOGY Degenerative process
Mayoccur due to exposure to s
unlight & dust
Inflammatory process
2’to chemicalburns,trauma.
LIMBAL RELATIONS Adhered to limbus Not adhered to limbus
ASSOCIATIONS Pinguecula ------
28. treatment
Early in the disease process, physicians often take a conservative approach,
limiting therapy to lubricating medications. Since UV radiation is believed
to be an important risk factor, the clinician should recommend that
patients with early-stage pterygia use proper protective eyewear. If the
lesion grows, surgical intervention becomes more compelling.
29. INDICATIONS
Surgical excision is the only satisfactory
treatment, which may be indicated for:
(1) Cosmetic reasons
(2) Continued progression threatening to
encroach onto the pupillary area (once
the pterygium has encroached pupillary
area, wait till it crosses on the other side)
(3) Diplopia due to interference in ocular
movements.
(4) Visual Impairment
Recurrence of the pterygium after surgical
excision is the main problem (30-50%).
30. PROCEDURE
Transplantation of pterygium in the lower fornix
(McReynold's operation) is not performed now.
Postoperative beta irradiations (not used now).
Postoperative use of antimitotic drugs such as
mitomycin-C or thiotepa.
Surgical excision with bare sclera.
Surgical excision with free conjunctival graft taken
from the same eye or other eye is presently the
preferred technique.
In recurrent recalcitrant pterygium, surgical excision
should be coupled with lamellar keratectomy and
lamellar keratoplasty.
31. In simple excision the conjunctiva is sutured
back to cover the sclera.
In bare sclera technique, some part of
conjunctiva is excised and its edges are sutured to
the underlying episcleral tissue leaving some bare
part of sclera near the limbus.
Free conjunctival membrane graft may be
used to cover the bare sclera. This procedure is
more effective in reducing recurrence. Free
conjunctiva from the same or opposite eye may be
used as a graft.
Limbal conjunctival autograft transplant-
ation (LLAT) to cover the defet after pterygium
excision is the latest and most effective technique
in the management of pterygium.