p ISSN
2723-6927-e ISSN 2723-4339
Overview
Pterygium
Universitas Alkhairaat
Palu, Indonesia
Email: ilmawati.016@gmail.com
ABSTRACT
Pterygium is a wing-shaped fibrovascular
growth extending from the conjunctiva onto the cornea. This review aims to
provide a comprehensive overview of pterygium, including its etiology, clinical presentation, diagnosis, treatment
options, and prognosis. A literature search was conducted using PubMed and
Google Scholar databases. Findings suggest that pterygium is primarily
associated with UV exposure and occurs more frequently in tropical and
subtropical regions. Diagnosis is primarily clinical, with treatment options
ranging from conservative management to surgical intervention. While generally
benign, pterygium can cause visual disturbances and has a significant
recurrence rate post-surgery.
Keywords: Pterygium, Surgical Intervention, UV
Exposure
Introduction
Pterygium,
derived from the Greek word "pterygos"
meaning "wing," is a common ocular surface disorder characterized by
a triangular or wing-shaped growth of fibrovascular tissue extending from the
conjunctiva onto the cornea (Coroneo, 1993). This
condition affects millions of people worldwide, with a higher prevalence in
regions closer to the equator, particularly between latitudes 37° north and
south of the equator (Liu et al., 2013).
Historically recognized since ancient times, pterygium has been a
subject of medical interest due to its potential to affect vision and its
tendency to recur after treatment (Rojas & Malaga, 1986). The
condition is believed to be primarily caused by excessive exposure to
ultraviolet (UV) radiation, although other factors such as chronic irritation
from dust, wind, and genetic predisposition also play significant roles (Jc, 2010).
The impact of pterygium on affected individuals can range from
mild irritation and cosmetic concerns to significant visual impairment. As the
growth extends onto the cornea, it can induce astigmatism, obstruct the visual
axis, and in severe cases, lead to blindness (Fotouhi et al., 2009). Moreover,
the management of pterygium, particularly surgical intervention, is associated
with a notable risk of recurrence, which remains a significant challenge in
ophthalmology (Clearfield et al., 2016).
Pterygium is a common ocular surface disorder characterized by the
growth of fibrovascular tissue from the conjunctiva onto the cornea (Coroneo, 1993). This
condition has been recognized since ancient times, with descriptions dating
back to Hippocrates in the 5th century BCE (Rojas & Malaga, 1986). Despite its
long history in medical literature, pterygium continues to be a significant
ophthalmic issue worldwide, particularly in tropical and subtropical regions (Liu et al., 2013).
The global prevalence of pterygium varies widely, ranging from
0.7% to 33% depending on the geographical location and population studied (Rezvan et al., 2018). This
variation is largely attributed to differences in ultraviolet (UV) radiation
exposure, which is considered the primary environmental risk factor for
pterygium development (Di Girolamo et al., 2004). Other
factors contributing to pterygium formation include chronic ocular surface
irritation, age, and genetic predisposition (Nemesure et al., 2008).
The pathogenesis of pterygium involves a complex interplay of
genetic and environmental factors leading to cellular changes in the
conjunctiva and cornea (Chui et al., 2011). These
changes result in the characteristic wing-shaped growth that can cause ocular
irritation, visual disturbances, and in severe cases, significant visual
impairment (Errais et al., 2008).
While pterygium is generally considered a benign condition, its
management poses several challenges. Conservative treatments are often
insufficient for advanced cases, necessitating surgical intervention (Kaufman et al., 2013). However,
the high recurrence rates following surgery, ranging from 2% to 89% depending
on the technique used, remain a significant concern for both patients and
ophthalmologists (Clearfield et al., 2016).
The etiology of pterygium involves multiple factors, primarily
linked to environmental exposures and genetic predisposition. Here's a detailed
explanation with references:
1. Ultraviolet
(UV) Radiation Exposure: Prolonged exposure to UV radiation, especially UV-B,
is widely acknowledged as the principal environmental risk factor for
pterygium. UV radiation can trigger oxidative stress, DNA damage, and
inflammation in the cells of the conjunctiva and cornea, contributing to the
development of pterygium (Taylor et al., 1988).
2. Chronic
Ocular Surface Irritation: Continuous mechanical irritation of the ocular
surface, such as from dust, wind, dryness, or contact lens use, is another
significant factor. This persistent irritation can disrupt epithelial cells,
provoke inflammation, and subsequently lead to the fibrovascular growth typical
of pterygium (Chui et al., 2011).
3. Genetic
Factors: Evidence suggests a genetic predisposition to pterygium. Studies have
identified several genetic variations associated with an elevated risk of
developing pterygium, indicating a familial clustering and genetic
susceptibility component (Holland et al., 2002).
4. Other Risk
Factors: Age, male gender, outdoor occupation, and geographical location
(closer to the equator) are additional factors linked to a higher prevalence of
pterygium, likely due to increased UV exposure (Detorakis & Spandidos, 2009).
These factors interact in a complex manner, influencing the
formation and progression of pterygium over time. Management and prevention
strategies typically focus on minimizing UV exposure and protecting the ocular
surface from chronic irritation.
Clinical
Presentation
The clinical presentation of pterygium includes several key
features that characterize this ocular condition:
1. Appearance:
Pterygium manifests as a triangular or wing-shaped growth on the conjunctiva,
extending onto the cornea. It typically originates from the nasal side of the
eye and can progress towards the center of the cornea over time (Coroneo, 1993).
2. Color and
Vascularity: The lesion often appears pinkish or fleshy due to its vascularity,
contrasting with the normal white sclera and clear cornea (Coroneo, 1993).
3. Symptoms:
Patients commonly report symptoms such as dryness, redness, irritation, foreign
body sensation, and occasional mild discomfort or pain (Coroneo, 1993).
4. Visual
Disturbances: As the pterygium advances onto the cornea, it may induce
irregular astigmatism or corneal distortion, resulting in blurred vision and
potentially affecting visual acuity (Coroneo, 1993).
5. Complications:
Severe cases can lead to corneal scarring, reduced visual acuity, and in rare
instances, may restrict eye movement if the growth is extensive (1993).
6. Bilateral
Occurrence: While pterygium typically affects one eye, bilateral occurrence is
possible in individuals with significant UV exposure or genetic predisposition (Di Girolamo et al., 2004).
The clinical presentation varies based on the stage and extent of
the pterygium. Management strategies range from conservative measures to
surgical removal, depending on the severity and impact on visual function.
Diagnosis
Diagnosis of pterygium is primarily based on clinical examination,
supported by patient history and sometimes imaging studies. Here’s how it is
typically diagnosed, referencing appropriate sources:
1. Clinical
Examination:
a. Visual
Inspection: Pterygium is identified as a triangular or wing-shaped growth on
the conjunctiva, extending onto the cornea, usually originating from the nasal
side of the eye (Coroneo, 1993).
b. Color and
Vascularity: The lesion appears pinkish or fleshy due to its vascularity,
contrasting with the normal white sclera and clear cornea (Coroneo, 1993).
c. Location and
Size: Its location and size are noted, and changes over time may be observed as
it progresses slowly.
2. Symptoms and
History:
Symptoms
commonly reported include dryness, irritation, redness, foreign body sensation,
and occasional mild discomfort (Coroneo, 1993).
3. Slit-Lamp
Examination:
Slit-lamp biomicroscopy is essential for detailed visualization. It
allows assessment of the extent of corneal involvement, evaluation of
vascularity, and examination for associated corneal irregularities or changes (Coroneo, 1993).
4. Imaging
Studies (Optional):
Anterior
segment optical coherence tomography (OCT) or ultrasound biomicroscopy
(UBM) may be used in some cases to assess the depth of pterygium invasion into
the cornea and to visualize its characteristics more precisely (Coroneo, 1993).
5. Differential
Diagnosis:
It’s
important to differentiate pterygium from other ocular surface lesions such as
pinguecula and conjunctival tumors through careful examination and evaluation
of clinical features.
Accurate diagnosis is crucial for appropriate management
decisions, considering both conservative and surgical options based on the
severity and impact on visual function.
Treatment
Treatment of pterygium involves various approaches depending on
the severity and impact on visual function. Here are
the typical treatment options supported by references:
1. Conservative
Management:
a. Artificial
Tears: Lubricating eye drops help alleviate dryness and irritation associated
with pterygium.
b. Steroid Eye
Drops: Short-term use of steroid eye drops can reduce inflammation and symptoms.
c. Sunglasses:
Encouraging UV-protective sunglasses usage to reduce UV exposure, a primary
risk factor for pterygium development.
2. Surgical
Removal:
a. Surgical
excision is considered for symptomatic or visually significant pterygium that
does not respond to conservative measures.
b. Techniques
include simple excision with or without grafting (autograft or amniotic
membrane graft) to reduce recurrence rates.
c. Adjuvant
therapies like mitomycin C or beta radiation may be used intraoperatively or
postoperatively to decrease the likelihood of recurrence.
3. Postoperative
Care:
a. Vigilant
monitoring post-surgery is crucial to detect recurrence and manage
complications effectively.
b. Regular
follow-up visits with an ophthalmologist are recommended to assess healing
progress and long-term outcomes.
4. Preventive
Measures:
a. Patient
education on UV protection and eye care practices to minimize the risk of
pterygium development or recurrence post-treatment.
b. Avoidance of
prolonged UV exposure and consistent use of protective eyewear during outdoor
activities are emphasized.
The choice of treatment is guided by the specific characteristics
of the pterygium and the patient's individual circumstances. Management
strategies aim to alleviate symptoms, prevent progression, and reduce
recurrence while preserving or restoring visual function.
Prognosis
The prognosis of pterygium, which refers to the likely course and
outcome of the condition, can vary based on several factors including the
severity of the pterygium, treatment approach, and individual patient
characteristics. Here are some key points regarding the prognosis of pterygium:
1. Recurrence:
One of the primary concerns with pterygium treatment is recurrence after
surgical removal. Recurrence rates can vary widely depending on the surgical
technique used, ranging from approximately 10% to 50% or higher in some studies
(Alsarhani et al., 2021).
2. Visual Impact:
In cases where the pterygium extends onto the cornea and causes irregular
astigmatism or corneal scarring, there may be a lasting impact on visual acuity
even after successful treatment (Anguria et al., 2014).
3. Complications:
Complications from surgical intervention, such as infection, delayed wound
healing, or graft failure (in cases of grafting procedures), can affect the
overall prognosis (Anguria et al., 2014).
4. Response to Treatment:
The prognosis also depends on how well the pterygium responds to treatment,
whether through conservative measures or surgical intervention. Early detection
and appropriate management can improve outcomes (Saw & Tan, 1999).
5. Long-Term
Monitoring: Long-term follow-up and monitoring are important to detect any
signs of recurrence or complications early, ensuring timely intervention if
needed (Saw & Tan, 1999).
6. Preventive
Measures: Educating patients about preventive measures, such as UV protection
and eye care practices, can help minimize the risk of recurrence and improve
long-term prognosis (Saw & Tan, 1999).
Overall, while pterygium is typically considered a benign
condition, its management and prognosis can be influenced by various factors.
Regular ophthalmic follow-up and adherence to preventive measures are crucial
for optimizing outcomes and maintaining eye health.
Research
Methods
The method
used in this research is the literature review method. The literature review
method is a systematic approach to collecting, assessing, and synthesizing
information from various literature sources relevant to a particular research
topic. The data collection technique is the documentation technique.
Documentation data collection techniques involve collecting information from
existing written, visual, or digital sources (Saw & Tan, 1999). Data
analysis using the Miles, Huberman, and Saldana model involves three main
steps: data reduction, data presentation, and conclusion drawing/verification.
Data reduction is the process of selecting, focusing, simplifying, abstracting,
and transforming raw data obtained from the field into a more organized and
meaningful form. The goal is to summarize and focus the data so that it is
easier to manage and analyze. Data presentation then involves structuring the
reduced information in a form that allows conclusions to be drawn, such as
matrices, graphs, networks, or diagrams. This step makes it easier for
researchers to see patterns, relationships, or trends in the data. Conclusion
drawing/verification is the final stage where researchers draw conclusions from
the processed data and verify these conclusions to ensure their validity (Miles & Huberman, 1994).
Results and Discussions
A pterygium
is a red or white growth of tissue that can appear on the surface of the eye,
usually on the conjunctiva, which is the thin layer covering the white of the
eye and the inside of the eyelid. Pterygium is often referred to as an “eye
wart” and can affect vision if it is large enough or grows towards the cornea
(the transparent part in front of the eye) (Chu et al., 2020). The main
cause of pterygium is overexposure to the sun's ultraviolet (UV) rays, which
damage the eye tissue and cause abnormal growth. In addition to UV rays,
environmental factors such as strong winds, dust and air pollution can also
increase the risk of pterygium, especially in areas that are frequently exposed
to such conditions. Exposure to eye irritants or chemicals, as well as genetic
factors, can also play a role in the development of pterygium. By protecting
the eyes from excessive exposure to sunlight and avoiding hostile environments,
the risk of pterygium can be reduced. If the pterygium has already appeared,
medication or surgery may be required to address the visual impairment and
discomfort caused (Van Acker et al., 2021).
Symptoms of
pterygium vary depending on the severity of the condition. In its early stages,
the pterygium often causes no obvious symptoms, but as it grows, sufferers may
feel discomfort such as itching, burning or irritation in the eye (Chen et al., 2023). The eye may
also become red or watery, and there may be a feeling of a foreign object
inside the eye. In more severe cases, pterygium can cause visual impairment as
the growing tissue covers part of the cornea and changes the shape of the eye.
Patients may experience blurred vision or image distortion. If the pterygium is
left untreated, the condition can grow larger and cause additional problems,
such as significant visual impairment and more severe eye irritation (He & Wu, 2022).
Diagnosis of
the pterygium is generally done through a comprehensive eye examination (Sulewski et al., 2023). The steps
usually taken to diagnose a pterygium are as follows.
1. Medical
History
The doctor will ask about the patient's medical history, including
symptoms, sun exposure, and environmental conditions.
2. Visual
Examination
The doctor will examine the patient's vision to determine if the
pterygium affects visual acuity or causes distortion.
3. Physical
Examination
The examination is performed using a slit lamp to view the
structures of the eye in detail. With this tool, the doctor can see the growth
of tissue in the conjunctiva and cornea and determine the size and extent of
the pterygium.
4. Assessment
Tests
The doctor may perform additional tests such as a fluorescein test
to evaluate damage to the surface of the eye or identify if there is any
infection or other irritation.
5. Comprehensive
Examination
Sometimes, the doctor will also examine the overall condition of
the eye to ensure that the pterygium is not part of another eye condition.
Treatment of the
pterygium can involve various methods, depending on its severity and impact on
the patient's vision and comfort (Akbari, 2022). Below is an
analysis of the various treatment methods for pterygium, including medical and
surgical therapies.
1.
Medical Therapy
a.
Anti-inflammatory Drugs
Topical corticosteroids are a common choice to treat pterygium
that causes inflammation and irritation. They work by reducing the inflammatory
response in the eye tissues, which can reduce redness, itching and discomfort.
This therapy is often effective for pterygiums that are not very large or to
control symptoms prior to surgery. However, long-term use or high doses can
have side effects, such as an increased risk of infection or thinning of the
eye tissue (Uba-Obiano et al.,
2021).
b.
Dry Eye Drops
For cases of pterygium that cause the eye to become dry or
irritated, artificial eye drops or eye moisturizers may provide temporary
relief. These eye drops help to keep the surface of the eye moist, reduce
itching, and provide comfort. While these are not a solution to eliminate the
pterygium, their use can help relieve bothersome symptoms (Baheran et al.,
2023).
c.
Immunosuppressive Drugs
In pterygiums that do not respond to corticosteroid therapy or
have recurrence, immunosuppressive drugs such as cyclosporine A may be used.
These drugs work by suppressing the local immune response in the eye, reducing
the inflammation that causes pterygium growth. This therapy is often chosen if
the pterygium is likely to recur after initial treatment or if the pterygium is
causing severe symptoms (Baheran et al.,
2023).
2.
Surgical Therapy
a.
Pterygium excision
Excisional surgical
procedure is the most common method to treat a pterygium that has progressed or
is causing visual impairment. In this procedure, the ophthalmologist removes
the pterygium tissue from the cornea and conjunctiva. The excision is performed
under local anesthesia to eliminate discomfort during the procedure. While this
is often effective, the risk of recurrence still exists, especially if the
pterygium tissue is not completely removed (Jirsova & Jones,
2017).
b.
Surgical Methods with the
Use of Grafts
To reduce the risk of
recurrence after excision, doctors may use the autologous conjunctival graft
technique, which involves taking healthy tissue from another part of the
patient's eye to cover the operated area. This technique reduces the chances of
the pterygium tissue growing back and provides a more natural eye surface for
healing. This method is generally more effective in preventing recurrence
compared to excision without a graft (Wanzeler et al.,
2019).
c.
Surgical Methods with
Antiproliferative Therapy
After pterygium excision,
some doctors use chemicals such as mitomycin C or 5-fluorouracil to prevent
regrowth. These chemicals are applied to the operated area during or after the
procedure to inhibit the proliferation of pterygium cells. This therapy helps
reduce the chances of recurrence, but requires careful monitoring to ensure
there are no side effects or complications.
3.
Postoperative Care
a.
Medication Use
After a surgical procedure,
patients usually need to take anti-inflammatory medications or antibiotics to
reduce inflammation and prevent infection. Anti-inflammatory drugs help manage
pain and swelling, while antibiotics prevent possible post-operative infections.
Proper post-operative care is essential for a good recovery and to minimize the
risk of complications.
b.
Routine Control
Post-operative check-ups are
essential to ensure that the operated area is healing well and that there are
no signs of complications or recurrence of the pterygium. The ophthalmologist
will monitor the healing process and make adjustments to the treatment if
necessary. Regular controls help detect problems early and ensure good
long-term results from the surgical procedure.
c.
Relapse Prevention
To prevent recurrence after
surgery, it is important for patients to avoid exposure to direct sunlight and
wear protective eyewear. In addition, keeping the eye free from irritants such
as dust and wind can help reduce the risk of the pterygium growing back.
Long-term care and lifestyle changes can support better outcomes and prevent
future problems.
Prevention of pterygium can be done by reducing the risk
of exposure to factors that can trigger pterygium growth (Kodavoor et al.,
2021). Here are some steps that can be taken to prevent
this condition:
1.
Protect the Eye from UV Rays
Exposure to the sun's
ultraviolet (UV) rays is a major factor in causing pterygium. To protect your
eyes, wear sunglasses with UV protection or a hat with a visor when outdoors.
Sunglasses with UV protection will help reduce the impact of sunlight on the
eyes.
2.
Avoiding Dirty Environments
Exposure to dust, strong
winds and air pollution can increase the risk of pterygium. If you work or move
in a dusty or polluted environment, wear eye protection or a mask to reduce
irritation. Keeping your surroundings clean can also help.
3.
Maintain Eye Health
Keeping your eyes clean by
washing your hands before touching your eyes and using artificial eye drops to
treat dry eyes can help reduce the risk of irritation that can contribute to
pterygium growth.
4.
Avoiding Irritant Exposure
If you are exposed to
chemicals or other irritants, wear appropriate eye protection and ensure the
work area is well ventilated. Avoiding direct exposure to irritants can help
prevent inflammation of the conjunctiva.
5.
Routine Examination
Having regular eye
examinations with an ophthalmologist can help detect early signs of pterygium
or other problems. Early screening allows for quick treatment if needed, which
can help prevent the condition from progressing to a more serious condition.
Pterygium can lead to various complications that affect
the patient's eye health and quality of life. One of the main complications is
visual impairment, as the growth of pterygium tissue covering the cornea can
cause blurred or distorted vision. The tissue covering the cornea can also
impair visual acuity and, in more severe cases, can affect the patient's
ability to see clearly (Jabbarli et al.,
2022). In addition, the pterygium can cause chronic eye
irritation, including itching, redness, and a sensation like there is a foreign
body inside the eye. If left untreated, the pterygium is at risk of recurrence
after the surgical procedure, especially if it is not removed completely or if
post-operative care is not followed properly. The long-term projection for
patients involves regular monitoring to detect possible recurrence and maintain
general eye health. Proper care and preventive measures, such as the use of
protective eyewear and maintaining eye hygiene, can help reduce the risk of
complications and improve the long-term prognosis. However, if left untreated,
pterygium can cause significant visual impairment and reduce the patient's
quality of life (Stevenson et al.,
2021).
Eye protection and proper use of eyewear play a crucial
role in reducing the risk of pterygium. The sun's ultraviolet (UV) rays are one
of the main factors that contribute to the development of pterygium, and
sunglasses with adequate UV protection can block UV rays from reaching the
eyes. By wearing glasses specifically designed to protect against UV rays,
especially when outdoors or in sunny conditions, the risk of developing
pterygium can be significantly reduced (Xiradis et al.,
2022). In addition, protective eyewear also helps protect
the eyes from dust, wind and other environmental irritants that can trigger or
worsen the condition. By integrating consistent eye protection in the daily
routine, individuals can reduce the negative impact of environmental factors
and maintain long-term eye health, which in turn reduces the risk of developing
pterygium and its associated complications (Zhang et al., 2023).
Thus, pterygium is a growth of conjunctival tissue that
extends into the cornea, often triggered by exposure to ultraviolet (UV) light
from the sun, as well as environmental factors such as dust and pollution.
Common symptoms include itching, redness and foreign body sensation in the eye,
as well as potential visual impairment if the pterygium progresses. Diagnosis
is done through a thorough eye examination, using tools such as a slit lamp to
assess its size and impact. Treatment may include medical therapy such as
anti-inflammatory medications and eye drops, or surgical therapy to remove the
pterygium tissue with additional methods such as conjunctival grafts or
antiproliferative therapy to reduce the risk of recurrence. Prevention involves
protecting the eyes from UV rays using sunglasses, as well as avoiding
environments that may cause irritation. Regular monitoring and proper treatment
are essential to prevent long-term complications and maintain overall eye
health.
Pterygium
remains a significant ocular surface disorder, particularly in tropical and
subtropical regions. While our understanding of its pathogenesis has improved,
challenges persist in preventing recurrence. Future research should focus on
developing targeted therapies and improving surgical outcomes.
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