clinical outcome of dalk in keratoconus – a one year follow up
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Clinical outcome of DALK in Keratoconus – A one year follow up. Authors: Somasheila I Murthy, MD, Smruthi rekha Priyadarshini , MD, Jagadesh Reddy, MD and Prashant Garg , MD. Affiliation: Cornea and anterior segment service, - PowerPoint PPT PresentationTRANSCRIPT
Clinical outcome of DALK in Keratoconus – A one year follow up
Authors: Somasheila I Murthy, MD, Smruthi rekha Priyadarshini, MD, Jagadesh Reddy, MD
and Prashant Garg, MD.
Affiliation: Cornea and anterior segment service, L. V. Prasad Eye Institute, Kallam Anji Reddy
Campus, Hyderabad, India
The authors have no financial interest in the subject matter of
this poster
•Study purpose: To evaluate the visual outcome and complications of deep anterior lamellar keratoplasty (DALK) in keratoconus
•Study design: retrospective interventional case series
•Study location: Cornea and anterior segment service, LV Prasad eye Institute, Hyderabad, India
Methods
•Inclusion criteria: all cases of keratoconus that underwent DALK with a minimum follow-up of one year
•Pre-operative evaluation included:
•Visual acuity•Slit lamp examination•Central corneal thickness•Corneal topography
The data obtained included: pre and post-operative:
•Best corrected Snellen’s visual acuity•Slit-lamp examination for assessment of graft clarity•Central corneal thickness •Corneal topography using Orbscan•Anterior segment optical coherence tomography post-operatively in some cases
Methods
•Surgical technique: •2 techniques:
•Big-bubble technique •Manual dissection in layers•Combination
•Primary outcome measures:•Visual acuity•Graft clarity
•Secondary outcome measures:•Nonprogression of keratoconus•Graft failure due to edema or rejection•Complications rate
•During 2004 to 2008, 49 eyes of 48 patients underwent DALK•Twenty-two eyes completed one year follow-up•Mean age: 18.63 (range 11 to 43 years) with 77% under 20 years•Fifteen were male and seven female patients
Results
Age Eyes (%)
11 – 20 yrs 17 ( 77%)
21 – 30 yrs 2 (9%)
31 – 40 yrs 2 (9 %)
> 40 yrs 1(4.5%)
Table 1: Age distribution
Visual acuity
> 20/ 60
Eyes
6
20/60 – 20/ 200 4
20/200 – 20/400 3
<20/400 13 (60%)
Table 2: Pre-operative visual acuity
Visual acuity
20/20-20/40
Eyes
16 (73%)
20/40-20/60 2
20/60-20/80 2
< 20/80 2
Table 3: Post-operative visual acuity
Results: pre and post-operative visual acuity
Results
Big bubble 7
Manual lamellar dissection
3
Combination 12
Total 22
Table 4: Surgical technique
•Corneal thickness ranged from 427 to 591 microns
•Donor graft size ranged from 7.5 to 10.5
Results: graft clarity and complications
Clear graft 16 (73%)
Interface haze 2
Scarring 3
Pigments on endothelium
1
Table 5: Graft clarity
Suture related
9
Vascularisation
3
PAS 1
None 8
Table 6: Complications
•Best-corrected visual acuity at one year was 20/40 or better in 16/22 cases (73%)
•16/22 cases had clear graft, with 5/22 showing interface haze or scarring
•No major complications like glaucoma, graft failure or progression were noted
•Minor suture related complications (loose or broken sutures) were noted in 9 eyes (40%)
Summary
•Penetrating keratoplasty is the accepted surgical treatment for keratoconus and has an excellent five-year graft survival rate1,2
•However, it can fail due to allograft rejection and endothelial cell loss
•Deep anterior lamellar keratoplasty replaces anterior diseased part of the cornea while retaining the host endothelium and has the advantage of reducing the risks of graft rejection and intraocular complications
Discussion
•Various authors have reported their results of DALK and have shown comparable visual acuities with PK with fewer post-operative complications3, 4,
5 Our study also shows similar results
• Therefore, despite this technique being more demanding surgically, it is worthwhile to perform DALK for keratoconus and PK should be done only as a last resort
Discussion
•Visual acuity outcomes of DALK in keratoconus are good in majority of cases
•In comparison to penetrating keratoplasty, there are fewer post-operative complications and majority encountered were minor
•DALK is perhaps the preferred choice for the surgical management of keratoconus
Conclusions
1. Pramnik S, Musch DC, Sutphin JE, Farjo AA. Extended long-term outcomes
of penetrating keratoplasty for keratoconus. Ophthalmology 2006;113:1633-
1638
2. Zadok D, Schwarts S, Marcovich A, et al. Penetrating keratoplasty for
keratoconus: long term results. Cornea 2005;24:959-961
3. Watson SL, Ramsay A, Dart JKG, et al. Comparison of deep lamellar
keratoplasty with penetrating keratoplasty in patients with keratoconus.
Ophthalmology, 2004;111:1676-1682
4. Sarnicola V, Toro P, Gentile D, et al. Descemetic DALK and pre-descemetic
DALK: outcomes in 236 cases of keratoconus. Cornea 2010 Jan;29(1):53-9
5. Han DY, Mehta JS, Por YM et al. Comparison of outcomes of lamellar
keratoplasty and penetrating keratoplasty in keratoconus. Am J Ophthalmol
2009;148(5):629-31
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