Deep anterior lamellar keratoplasty in children

1. Deep anterior lamellar keratoplasty in children World Cornea Congress April 2010 Boston, MA Asim Ali, MD, FRCSC University of Toronto Hospital for Sick Children Toronto, Ontario, Canada Disclosure: The author has no financial interests related to the material of this poster.

2. Abstract Purpose To present a series of pediatric patients who underwent deep anterior lamellar keratoplasty (DALK) for stromal opacities or ectasia by one surgeon from 2007-2009. Methods A retrospective review of 12 consecutive patients with attempted DALK, age less than 18 years and follow-up of at least 4 months was performed. Indications for surgery, length of follow-up, complications and initial and final visual acuity were recorded. Results Successful DALK was performed in 12 eyes of 11 patients aged 1-17 years old. There was one macroperforation and conversion to penetrating keratoplasty. Non-healing epithelial defects occurred in 2 patients who developed microbial keratitis. Repeat DALKs were performed successfully. One patient developed reactivation of HSV in the graft and because of dense amblyopia a repeat graft was not attempted. Final visual acuity was unchanged or improved in all patients. Conclusions Deep anterior lamellar keratoplasty is a safe alternative to penetrating keratoplasty in children with corneal stromal opacities or ectasia.

3. Methods • Records of 13 eyes of 12 consecutive patients with attempted DALK were reviewed • Single surgeon from 2007-09 • Surgical technique used • Melles technique (1 case) • Manual dissection (12 cases) • Trephination (Hessberg-Barron, 300-350 microns) • Sharp and semi-sharp dissection to pre-Descemet’s plane • Air injected to visualize stroma but big bubble not attempted

4. Results • 12/13 eyes underwent successful manual DALK • 1 eye was converted to PKP because of macroperforation • 4 microperforations occurred but dissection was completed successfully • 2 repeat DALKs (with tarsorraphy) were performed after persistent epithelial defects resulted in bacterial keratitis – both remain clear • Vision remains unchanged or improved in all patients • Grafts are clear in 11/12 eyes with mean follow-up of 11.8 months (range 6-22)

5. Table 1: Pre-operative characteristics * Central, steady + unmaintained

6. Table 2: Operative details

7. Table 3: Post-operative course

8. Figure 1: Slit lamp photo of patient 6 showing anterior stromal scar and thinning

9. Figure 2: Slit lamp photo of patient 12 showing Vogt striae and deep scarring

10. Discussion • DALK was selected instead of PKP in our pediatric patients because of a lower risk of rejection and greater tectonic strength. Two of our patients (3 and 8) were forceful eye rubbers with psychiatric co-morbidities and the improved strength was reassuring. • A manual technique instead of a big bubble technique was used to allow dissection of deep scars and minimize perforations, as we believe the benefit of reduced rejection outweighs the visual benefits in this patient group with other ocular co-morbidities especially amblyopia. • The high rate of perforation may reflect the deep scarring in some corneas and also surgeon inexperience. • Satisfactory visual outcomes were achieved even when residual corneal opacities remained in the recipient bed. • Persistent epithelial defects lead to bacterial superinfection in two patients and we now perform temporary and permanent tarsorraphies following DALK surgery in susceptible patients.

11. Conclusions • Manual DALK in children leads to improved visual outcomes, and in our view has significant advantages over PKP in this high risk group.