Dr. K.S.SIDDHARTHANAravind Eye Hospital
Coimbatore
The author has no financial interest in the subject matter of this poster.
Deep Anterior Lamellar Keratoplasty (DALK) Vs Penetrating Keratoplasty
(PK) in patients with Keratoconus (KC).
IntroductionDeep Anterior Lamellar Keratoplasty [DALK] has been
recommended as an alternative to Penetrating keratoplasty( PK) for the treatment of keratoconus.
Corneal graft failure in PK is most frequently the result of destruction of the donor endothelium by inflammatory cells during acute or chronic allograft rejection.
Comparative studies with PK have shown overall similar visual outcomes when both techniques are used .
The main disadvantage of DALK is of being both a technically more challenging and time consuming procedure with a steep learning curve compared to PK.
In this study we report the comparison of clinical outcomes of DALK Vs PK.
Purpose To compare the clinical outcomes of Deep
Anterior Lamellar Keratoplasty and Penetrating Keratoplasty in patients with keratoconus.
MethodsProspective & Interventional case series. 66 eyes of
53 consecutive patients with KC who underwent DALK and PK between September 2003 to April 2009 were routinely included.
Visual and refractive outcomes at 1,3,6,12 months were analyzed. Complication rates were also analyzed.
Data AnalysisComparison ofVisual acuity - (Uncorrected and Best
corrected) at 1 month and 1 year – Chi Square test.
Spherical equivalents - (non- normal distribution - Mann Whitney U test).
Complication rates – Compared Between DALK and PK.
Uncorrected Visual acuity p-0.639 (NS)
Visual Outcome at 1 month
Best corrected Visual acuity p-0.242 (NS)
RESULTS
Uncorrected Visual acuity p-0.830 (NS)
Visual Outcome at 1 Year
Best corrected Visual acuity p-0.862 (NS)
Spherical Equivalent
Complications
There was no intra operative complication in PK compared to 27.3% in DALK.
Postoperative graft infection was not statistically significantly different between the two surgery types (DALK – 5.3% vs PK - 9.1%) (p-0.527).
Post operative graft rejection was seen in one patient with PK.
Complications of DALK
Suture related Graft Melt
Graft Infection Descemet’s Tear
Inter phase Debris
Descemet’s Detachment
Summary Visual improvement in DALK (83% ) was better than PK (63.4%) at 1
month. However, at 1 year the visual improvement between the two procedures were comparable (92.5% in DALK and 90.9% in PK).
The average difference made in spherical equivalent at 1 year compared to preoperative period was 10.5±7.5 in DALK and 19.2±5.2 in PK. The impact on spherical equivalent by PK was statistically significantly higher (p-0.003).
Intra operative complications were more in DALK ,compared to PK.
Conclusions Penetrating keratoplasty is no longer an
automatic choice for the surgical treatment for keratoconus.
Best-corrected visual acuity and refractive results are similar after DALK and PK.
DALK allows earlier visual rehabilitation, use of low dose steroids for shorter duration and earlier suture removal compared to PK.
DALK is more technically challenging but allows the risk of endothelial rejection to be avoided.
DALK is a safe alternative to penetrating keratoplasty in patients with keratoconus.
BibliographyTroutman RC, Lawless MA. Penetrating keratoplasty for
keratoconus. Cornea 1987;6:298 –305.Panda A, Bageshwar LM, Ray M, et al. Deep lamellar
keratoplasty versus penetrating keratoplasty for corneal lesions. Cornea 1999;18:172–5.
Jun Shimazaki, Shigeto Shimmura et al .Randomized Clinical Trial of Deep Lamellar Keratoplasty Vs Penetrating Keratoplasty. Am J Ophthalmol 2002;134:159–165.
Stephanie L. Watson, FRANZCO et al .Comparison of Deep Lamellar Keratoplasty and Penetrating Keratoplasty in Patients with Keratoconus. Ophthalmology 2004;111:1676–1682