Transcript Long-Term Outcomes of Keratolimbal Allografts and Conjunctival

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, EBOD
A. 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).
LSCD aetiology
Percentage
Chemical injury
39%
Aniridia
23%
Epithelial dysplasia
15%
Pseudopterygia
15%
Trachoma
8%
• Immunomodulation was tailored to each individual case.
Immunomodulation
Percentage
Topical steroids
100%
Oral steroids
46%
Oral steroids & cyclosporine
15%
Results
• 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.
Visual
acuity
Percentage
Mean
Improved
8/13 (62%)
2.8 Snellen
lines
Stable
2/13 (15%)
-
Declined
3/13 (23%)
1.0 Snellen
line
Results
• 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.
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.