Deep Anterior Lamellar Keratoplasty (DALK) Vs Penetrating Keratoplasty (PK) in patients with Keratoconus (KC). Dr. K.S.SIDDHARTHAN Aravind Eye Hospital.

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.

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