In Nepal, corneal blindness is the second major cause of blindness after cataract. Corneal disease affects mainly young adults and people of a productive age, yet more than half of these cases are preventable. The corneal service at TIO is run by three dedicated cornea and anterior segment specialists.
Penetrating Keratoplasty (PKP) is a full thickness corneal transplant. It is the main corneal surgery performed at TIO. The most common indications of PKP are infective keratitis followed by corneal scars.
Lamellar Keratoplasty (LK) is a partial thickness transplant procedure that has gained popularity throughout the world and in TIO.
Deep Anterior Lamellar Keratoplasty (DALK) replaces the front of the cornea and is performed for selected patients with keratoconus, anterior stromal scars and stromal dystrophies. Graft rejection is less in DALK as compared to traditional corneal transplants, thus DALK is a very useful technique for countries like Nepal where patient follow up may be difficult.
Descemet Stripping Automated Eendothelial Keratoplasty (DSAEK) is another recently developed corneal lamellar surgery that is currently being performed at TIO. In this technique, no sutures are used and the shape of the natural outer cornea is not changed. As a result the visual outcome of DSAEK has been very good compared to penetrating keratoplasty. Since only the inner lining of the cornea is replaced the globe is a lot stronger in DSAEK as compared to PKP.
Keratoprosthesis: In this surgery the patient’s cornea is replaced by an artificial synthetic cornea. This surgery is indicated in cases where penetrating keratoplasty has a poor prognosis, such as repeated graft failure, chemical injury and limbal stem cell loss or severe corneal vascularization.
Other surgeries performed by the cornea service are scleral graft, Gunderson’s flap, limbal stem cell transplant (autograft or allograft), corneal glue, Pterygium surgery with conjunctival graft (shown to have a very small recurrence) and complicated cataract surgeries etc.
The corneal department also undertakes both the medical and surgical management of ocular surface tumours such as squamous cell carcinoma and malignant melanoma.
The most common corneal problems presenting in the subspeciality clinic are viral keratitis, microbial keratitis, corneal scars, keratoconjunctivitis and cases of post-operative corneal grafts.
Aside from the provision of quality patient care the cornea service is also engaged in training and research activities.