pellucid marginal degeneration

1. Pellucid marginalPellucid marginal
degenerationdegeneration
With emphasis on surgicalWith emphasis on surgical
managementmanagement
PushParaj singh

2. Pellucid marginal degenerationPellucid marginal degeneration
• Schalaeppi (1957)
• Bilateral, noninflammotry,
• Ectatic inferior cornea(crescentic)
• Thinning extends from the 4-8 o’clock
position, 1 mm from the limbus.
• Epithelium intact, and the cornea above
the thinned out area is ectatic

4. • The area between
the limbus and
thinning is
1. Clear,
2. NO Scarring
3. NO Lipid deposition,
4. NO vascularization.
• Age group- 30-40
yr

5. • Flattening of the cornea along a vertical
axis
• Steepening of the inferior cornea
peripheral to the site of the lesion (ATR)

6. DiffrentialDiffrential
DiagnosisDiagnosis

7. KERATOCONUSKERATOCONUS

8. Terrien marginalTerrien marginal
degenerationdegeneration

9. KERATOGLOBUSKERATOGLOBUS

10. MOORENS ULCERMOORENS ULCER

11. MANAGEMENTMANAGEMENT
• Spectacles:-small horizontal eye
sizes, & high refractive index
lenses with antireflective coating
• Contact lenses:- RGP, Toric lenses,
scleral lenses
• Verisye/ Artisan phakic iol*
*De verrien NE. cornea 2008;27:241-45

12. Acute hydropsAcute hydrops
• Risk factor:- Ocular allergy,Eye
rubbing,Down syndrome,
• C/O:- blurred vision, irritation, pain,
watering, photophobia
• Mx:- conservative
• Hypertonic agents, steroids, antibiotics,
cycloplegics, hypotensive agents
• Bandage Contact lens
• BCL & Cyanoacrylate glue (in
perfoation)

13. AIRAIR Miyata K et al .Miyata K et al .Am J Ophthalmol. 2002 Jun;133(6):750-2Am J Ophthalmol. 2002 Jun;133(6):750-2
• acts as temponade, stretches both
ends of ruptured DM
• 0.1 ml (1-4 times)
• 4-24 days to resolve edema(2-4 mth in
conservative mx)
• Complication:- infection, IOP rise,
pupillary block, endothelial cells
damage

14. CC33FF8 &8 & SFSF66
• Acts as mechaical barrier, preventing aqueous
humour into stroma & as temponade
• *C3F8- 0.1-0.2 ml, 10-14 % nonexpansile conc
• **SF6- 0.2ml, iso-expansile conc (18%)
intracamerally
*Shah SG et al.Am J Ophthalmol. 2005 Feb;139(2):368-7
**Vanathi M et al.Cont Lens Anterior Eye. 2008 Feb 19

15. SURGICAL MAMAGEMENTSURGICAL MAMAGEMENT
•INTACS
•Eccentric PKP
•Full thickness wedge resection
•Lamellar crescentic resection
•Large diameter epikeratoplasty
•lamellar crescentic keratoplasty
•Comb. Of lamellar crescentic +
PKP

16. INTACSINTACS
Allsandro et al.ophthalomology 2005;112:660-66Allsandro et al.ophthalomology 2005;112:660-66
• Crescent shaped(PMMA), arc
length of 150°
• Inner diam.-6.8 mm,outer diam.-
8.1 mm
• 0.25 superior, 0.45 inferior side
• Inferior cornea thickness >
450μm(7mm optical zone)
• Temporal 1.8 mm incision (70%
depth)
• FM lasers:- used to create intra
stromal tunnel (Ertan A.JCRS,2006;32:1710-16)

17. principleprinciple
• New optical zone, separates the
ectatic area from central zone
• Spherical equivalent, reduced by
flattening action of 2 opposite ring
• Inferior ring causes a barrier effect
against high astigmatism induced by
PMD towards central cornea
• Stabilization & elimination of the
progression of ectatic disease

18. Eccentric PKPEccentric PKP
• Large graft required (9-10mm) with
same recipient bed or 0.5 larger
• Increased risk for vascularisation
• High postop. Astigmatism
• Increased rejection(64% >
keratoconus)
• In one study 7 out 11 eyes,
endothelial rejection occurred*
* Gary A. Am.J.Ophthalmol 1990,110:149

19. Large diameter epikeratoplasty*Large diameter epikeratoplasty*
*Aldo Fronterre.Cornea 1991; 10(5):450-453*Aldo Fronterre.Cornea 1991; 10(5):450-453
• Commercially prepared tissue lens
(KERATO-LENS)
• Large graft (9-12mm)
• Lenticules sutured as epikeratophakia
• Comp.- neovascularisation, rejection

20. Lamellar crescentic keratoplastyLamellar crescentic keratoplasty
schanzlin J.am jschanzlin J.am j
ophthalmol.1983;96(2)253-254ophthalmol.1983;96(2)253-254
• Tectonic graft
• Limited to thinned area
• Sutured with nylon 10-0

21. Lamellar crescentic+ PKPLamellar crescentic+ PKP
Robinwitz et al.ophthalomology 2000 oct.107(10)1836-40Robinwitz et al.ophthalomology 2000 oct.107(10)1836-40
• Simultaneous peripheral crescentic LK &
central PKP
• Tendency for increased WRA Noted in
long term

22. Lamellar crescentic resectionLamellar crescentic resection
Principle
• Excise abnormal crescentic thinned stroma
• Approximate normal thickness stroma to
normal thickness stroma
• Aim for overcorrection of astigmatism
(WRA), Upto 50 % (Troutman)
• Adv:- localised to abnormal area
incision smaller
no donor tissue- no rejection

23. Disadv:- visual acuity poor for 6Disadv:- visual acuity poor for 6
monthmonth
long term astigmatism driftlong term astigmatism drift

25. WEDGE RESECTIONWEDGE RESECTION
• PRINCIPLE:- same as crescentic
resection
• Inferior full thickness crescentic
wedge (2mm) removed
• Wound is approximated by 10-15
nylon or polypropylene 10-0 suture
• LTAD monitored
• Adv-disadv:- same as crescentic
resection