A corneal ulcer is defined as a disruption or open sore in which layer of the cornea?

The outer epithelial layer A corneal ulcer begins as a disruption or open sore of the outer epithelial surface; extension into the deeper stroma is what defines a stromal ulcer.

What is the typical healing time for most superficial corneal ulcers?

3 to 5 days Most superficial corneal ulcers close in three to five days; failure to heal within a few days raises the risk of infection and extension into the stroma.

What characterises a "melting" corneal ulcer?

Softening of the cornea by enzymatic breakdown of collagen In a melting ulcer, enzymatic degradation of corneal collagen leaves the cornea very soft, and the globe can rupture within hours to days of infection.

Calcium deposition within the corneal stroma

Progressive thinning from chronic endothelial failure

Separation of epithelium from Bowman's layer

Persistent trauma from which of these will delay corneal ulcer healing indefinitely?

An abnormal eyelash or retained foreign body Continuous mechanical trauma from an aberrant lash or a retained foreign body prevents an ulcer from closing, which is why the slit lamp examination must hunt for both.

Raised episcleral venous pressure

Why does an established corneal epithelial defect so readily become infected?

Resident bacteria on the eye and lids colonise the defect A low population of bacteria normally lives on the ocular surface and lids; once a corneal defect exists they colonise it, and rapid corneal degradation can follow.

The cornea loses its avascular status within hours

Tear lysozyme is destroyed by stromal oedema

Aqueous humour leaks forward through Bowman's layer

What does fluorescein bind to when it is used to assess a corneal ulcer?

Exposed corneal stroma Fluorescein staining is an essential test because the dye binds exposed corneal stroma, revealing both the size and the depth of the ulceration.

Which test is included in the corneal ulcer work-up to establish whether tear production is normal?

Schirmer tear test Schirmer tear testing is performed alongside slit lamp biomicroscopy to determine whether tear production is adequate, since dry eye itself can drive serious ulceration.

At what depth of corneal involvement is surgery recommended for a stromal corneal ulcer?

When 50% or more of corneal thickness is involved Once an ulcer involves half or more of the corneal thickness, surgery is advised to forestall corneal perforation and loss of vision.

As soon as any stromal fibres are exposed

When 10% or more of corneal thickness is involved

When 25% or more of corneal thickness is involved

Which combination makes up the medical management of a stromal corneal ulcer?

Frequent topical antibiotics with serum or plasma Medical treatment rests on frequently instilled topical antibiotics together with a blood product (serum or plasma), with sodium hyaluronate lubrication to aid healing.

Topical antivirals with oral acetazolamide

Topical steroid alone with firm patching

Oral doxycycline with pilocarpine drops

Which surgical technique is used to stabilise a deep stromal corneal ulcer?

Intrastromal corneal ring segments

Pterygium excision with bare sclera

Stromal Corneal Ulcers: disease entity, diagnosis and management

Abstract

A corneal ulcer is a disruption or open sore in the outer surface (epithelial) layer of the cornea. Corneal ulcers are frequently caused by some form of eye injury.

Typical healing time for most superficial ulcers is 3-5 days. Ulcers that do not heal within a few days can become infected, and /or extend into the deeper layers of the cornea (called stroma).

Stromal ulcers can develop for a variety of reasons. Persistent trauma to the surface of the eye by an abnormal eyelash or retained foreign body will delay healing indefinitely.

Conditions such as dry eye, glaucoma, and uveitis can also lead to serious corneal ulcers. Most commonly, ulcers worsen due to infection.

A low population of bacteria is naturally present on the surface of the eye and eyelids. If there is an ulcer on the cornea, these bacteria take the opportunity to colonize (grow) the defect, which can lead to rapid corneal degradation.

Ulcers are referred to as “melting” if the cornea becomes very soft due to enzymatic degradation and breakdown of the corneal collagen. This can lead to rupture of the eye within hours to days of infection and potential loss of the eye.

Stromal Corneal Ulcers Diagnosis

Slit lamp biomicroscopy is used to examine the cornea under a high degree of magnification, and assess the extent and depth of the ulcer.

The slit lamp is also used to look for the potential cause of the ulcer, such as abnormal eyelashes or retained foreign bodies. Schirmer tear testing is also performed to determine if tear production is normal.

Fluorescein staining is an essential diagnostic test and will bind to exposed corneal stroma, to reveal the size and depth of the ulceration.

Depending on the depth, clinical appearance, and history of the ulceration, additional diagnostic testing such as corneal cytology and corneal culture may be recommended.

Test your knowledge 10 questions from this article

Stromal Corneal Ulcers Treatment

Medical management of stromal ulcers involves the frequent instillation of topical antibiotics, as well as a blood product called serum or plasma.

Frequent lubrication with sodium hyaluronate can also aid healing. Additional topical and systemic medications are used to reduce associated eye inflammation and pain.

Our patients are monitored closely and frequently to monitor for progress in healing, as significant changes can occur in a matter of hours.

If an ulcer involves 50% or more of the corneal thickness, surgery may be recommended to avoid corneal perforation and loss of vision.

Surgical techniques include the use of corneal grafts or transplants, conjunctival pedicle or island grafts, and other biological graft material to stabilize the cornea. These grafts become incorporated into the patient’s cornea.

Stromal Corneal Ulcers Prognosis

When treatment is sought early, the vast majority of ulcers will heal and at least partial vision will be preserved. These reparative corneal surgeries typically carry a 90% success rate.

As with any surgical procedure, there are potential complications. These include wound dehiscence, graft rejections, persistent infection at the surgical site or inside the eye, corneal scarring, corneal vascularization, corneal mineralization, chronic uveitis, glaucoma, retinal detachment, hyphema (bleeding inside the eye), blindness and loss of the eye.

Our primary goals with medical or surgical treatment of deep corneal ulcers are to preserve the best vision possible in our patients and to control any pain or discomfort they may experience.

Test yourself

A few questions straight from this article.

1 / 10 0 correct

A corneal ulcer is defined as a disruption or open sore in which layer of the cornea?
A corneal ulcer begins as a disruption or open sore of the outer epithelial surface; extension into the deeper stroma is what defines a stromal ulcer.
What is the typical healing time for most superficial corneal ulcers?
Most superficial corneal ulcers close in three to five days; failure to heal within a few days raises the risk of infection and extension into the stroma.
What characterises a "melting" corneal ulcer?
In a melting ulcer, enzymatic degradation of corneal collagen leaves the cornea very soft, and the globe can rupture within hours to days of infection.
Persistent trauma from which of these will delay corneal ulcer healing indefinitely?
Continuous mechanical trauma from an aberrant lash or a retained foreign body prevents an ulcer from closing, which is why the slit lamp examination must hunt for both.
Why does an established corneal epithelial defect so readily become infected?
A low population of bacteria normally lives on the ocular surface and lids; once a corneal defect exists they colonise it, and rapid corneal degradation can follow.
What does fluorescein bind to when it is used to assess a corneal ulcer?
Fluorescein staining is an essential test because the dye binds exposed corneal stroma, revealing both the size and the depth of the ulceration.
Which test is included in the corneal ulcer work-up to establish whether tear production is normal?
Schirmer tear testing is performed alongside slit lamp biomicroscopy to determine whether tear production is adequate, since dry eye itself can drive serious ulceration.
At what depth of corneal involvement is surgery recommended for a stromal corneal ulcer?
Once an ulcer involves half or more of the corneal thickness, surgery is advised to forestall corneal perforation and loss of vision.
Which combination makes up the medical management of a stromal corneal ulcer?
Medical treatment rests on frequently instilled topical antibiotics together with a blood product (serum or plasma), with sodium hyaluronate lubrication to aid healing.
Which surgical technique is used to stabilise a deep stromal corneal ulcer?
Corneal grafts, conjunctival pedicle or island grafts and other biological graft materials are used to stabilise the cornea, and they become incorporated into the host cornea.