Long-term outcomes of keratolimbal allografts and conjunctival limbal autografts for total limbal stem cell 

deficiency

M. Ziaei MBChB (Hons), FRCOphth L. Ficker MBBS, BSc, FRCS, FRCOphth, EBODA. Shortt MBBCh, MSc, PhD, FRCOphth

The authors have no financial disclosures to declare. Moorfields Eye Hospital, London, UK

Introduction• Corneal stem cells are principally located at the sclerocorneal limbus, and are

indispensable for the maintenance of a healthy corneal surface. • Limbal stem cell deficiency (LSCD) can be associated with persistent epithelial

defects, vascularisation of the cornea, conjunctivalisation of the cornea, corneal scarring, melting, ulceration and perforation of the cornea, corneal calcification, and band keratopathy

• Stem cell transplantation has been used for over twenty years for the treatment of LSCD ever since Kenyon and Tseng reported that an abnormal corneal epithelial phenotype can be normalized by the surgical transfer of limbal tissue containing stem cells.

• Further modifications of this surgical procedure include eccentric penetrating keratoplasty, conjunctival limbal autograft (CLAU), living-related conjunctival limbal allograft (lr-CLAL) and keratolimbal allograft (KLAL).

Purpose

• To evaluate the long-term (10 year) outcomes of ocular surface reconstruction using KLAL and CLAU in patients with total limbal stem cell deficiency.

Methods

• A retrospective non-comparative review of thirteen eyes of 11 patients with total LSCD at a tertiary referral centre was performed.• All patients had a preoperative best-corrected Snellen visual acuity of less than 6/36.• All patients underwent a single KLAL or CLAU procedure. • If needed, penetrating keratoplasty (PKP) was performed at the same surgical setting.• Impression cytology was performed in all patients after the 6th postoperative month.•All patients had a minimum follow-up of 5 year.

Results

• Ten eyes (77%) received KLAL and three eyes CLAU (23%). • Surgery was uneventful in all eyes with only one case of inadvertent

perforation encountered. • Mean follow-up was 120.0 ± 40.3 months (60.5 - 180.6 months).

• Immunomodulation was tailored to each individual case.

LSCD aetiology Percentage

Chemical injury 39%

Aniridia 23%

Epithelial dysplasia 15%

Pseudopterygia 15%

Trachoma 8%

Immunomodulation Percentage

Topical steroids 100%

Oral steroids 46%

Oral steroids & cyclosporine 15%

• The overall survival of ambulatory vision (VA > 6/60) was 53.8% at final follow-up. • There was no significant difference between patients receiving KLAL and CLAU.• One patient who underwent KLAL developed an episode of rejection which was

successfully treated with topical and oral steroids.

Results

Visual acuity

Percentage Mean

Improved 8/13 (62%) 2.8 Snellen lines

Stable 2/13 (15%) -

Declined 3/13 (23%) 1.0 Snellen line

• One patient who underwent KLAL developed an episode of rejection which was successfully treated with topical and oral steroids.

• Three patients developed raised IOP and two were treated successfully with topical antihypertensives.

• Seven patients underwent cataract surgery. The mean time to cataract surgery from limbal stem cell transplant was 48 months.

• At final follow-up graft clarity was maintained in 10 (76%) eyes.• Impression cytology results revealed a normal corneal phenotype in only 3 (23%)

eyes. The rest of the eyes had evidence of conjunctival morphology (CK19+) with presence of goblet cells or had a mixed appearance showing corneal and conjunctival cell morphology.

• There was no significant difference between patients receiving KLAL and CLAU.

Results

Conclusion

• Keratolimbal allografts and conjunctival limbal autografts can provide long term benefits, as measured by objective criteria.

• In our series an improved visual acuity was seen in two thirds of treated patients with LSCD and this was maintained for up to 10 years.

• However, such benefits do not necessarily correlate with survival of measurable numbers of donor cells on the ocular surface as evident by impression cytology outcomes demonstrating restoration of a normal corneal phenotype in only 23% of cases.

• Allograft and autograft outcomes were similar in our case series.