https://doi.org/10.1177/1120672120945907
European Journal of Ophthalmology
1–7
© The Author(s) 2020
Article reuse guidelines:
sagepub.com/journals-permissions
DOI: 10.1177/1120672120945907
journals.sagepub.com/home/ejo
EJO
European
Journal of
Ophthalmology
Introduction
Superficial corneal scars due to various causes are usually
treated by phototherapeutic keratectomy (PTK)
1
or ante-
rior lamellar keratoplasty procedures as sutureless anterior
lamellar keratoplasty (SALK)
2
or femto assisted lamellar
keratoplasty (FALK) depending on the depth and location
of the lesion.
3
Some of the common indications for devel-
oping visually significant corneal opacities are post-kerati-
tis scarring, post corneal trauma, band shaped keratopathy,
spheroidal degeneration, superficial corneal dystrophy,
post photorefractive keratectomy (PRK) haze, or a LASIK
flap associated scarring and/or epithelial ingrowth.
A side-effect of PTK is a hyperopic shift due to ablation
of the corneal tissue, which may require additional exci-
mer laser treatment to counteract induced refractive
errors.
1,4
PTK conventionally is a planar circular ablation
within a 6 to 8 mm diameter; the deeper the ablation, the
greater the chance of development of haze, and induced
refractive change.
5,6
The shape of the ablation profile is
always circular and not customized to the scar shape;
therefore, the procedure often involves incorporation of
relatively normal cornea. Though VISX S4 (AMO, Santa
Topography-based customized
trans-epithelial phototherapeutic
keratectomy for anterior corneal
scar removal
Rohit Shetty
1
, Rushad Shroff
2
, Aishwarya Chhabra
1
,
Ritu Arora
3
and Vaitheeswaran Ganesan Lalgudi
1
Abstract
Purpose: To report a case of management of a post-LASIK superficial corneal scar using a novel single-step topography-
based customized phototherapeutic keratectomy (PTK).
Methods: Surgical technique description.
Results: Ablation was planned using Schwind Amaris
®
1050RS excimer laser as decentered trans-epithelial PTK of
5 mm × 3.5 mm of 75 μm depth exactly over the area of the scar. UDVA, CDVA improved from 20/60 and 20/40 pre-
operatively to 20/30 and 20/20p post-operatively. Refractive error improved from -2.5 DC @135 to +0.25 DS/-0.25 DC
@75. Regularization of topography and stromal surface on ASOCT was noted with minimal hyperopic shift. Another
step of ablation to address induced hyperopia was not required.
Conclusion: Topography-based customized PTK appears to be an effective novel technique for the management of
superficial corneal scars with minimal induced refractive change. This technique holds promise as an alternative in the
targeted management of superficial corneal scars, traditionally treated by conventional PTK, without significant ablation
of normal tissue.
Keywords
Anterior corneal scars, customized PTK, tissue sparing PTK
Date received: 17 February 2020; accepted: 9 July 2020
1
Department of Cornea and Refractive surgery, Narayana Nethralaya,
Bangalore, India
2
Shroff Eye Centre, New Delhi, India
3
Guru Nanak Eye Centre, Maulana Azad Medical College, New Delhi,
India
Corresponding author:
Vaitheeswaran Ganesan Lalgudi, Department of Cornea and Refractive
surgery, Narayana Nethralaya, #121/C Chord road, 1st R block, Rajaji
Nagar, Bangalore 560010, India.
Email: kanthjipmer@gmail.com
945907EJO 0 0 10.1177/1120672120945907European Journal of OphthalmologyShetty et al.
research-article 2020
Surgical technique