Clinical Study Scleral Lenses in the treatment of Neurotrophic | Page 5

Table II: Clinical Findings on Initial Presentation to the Contact Lens Clinic
resolve this issue could be to con-sider a
piggy-back system, which implies fitting
Clinical Findings OD
OS
Unaided Visual Acuities 6/12 -2
6/9 -1
Cycloplegic Refraction +4.75 −1.25 × 130
with VA: 6/7.5
+3.25 −1.50 × 175
with VA: 6/7.5
Anterior Segment
Evaluation Cornea:
Cornea:
Mid-peripheral
scarring
 Mild to moderate central haze

Moderate
diffuse
without scarring

punctate epithelial
 Moderate diffuse punctate
erosions (positive staining)
epithelial erosions (positive
staining)
TBUT:
TBUT:
 >10s (normal)
 >10s (normal)
Lacrymal lake:
Lacrymal lake:
 Moderately reduced at inferior
 Moderately reduced at
inferior margins
margins
Dilated Fundus
examination Optic nerve:
 Unremarkable
Macula:
 Unremarkable
Vessels:
 Unremarkable
Periphery:
 No breaks, holes or tears 360
a high oxygen perme-ability soft lens
Optic nerve:
 Unremarkable
Macula:
 Unremarkable
Vessels:
 Unremarkable
Periphery:
 No breaks, holes or tears 360
carrier on top of which a high
permeability RGP lens
is fitted. In that way, the soft carrier
aims to protect the cornea while the
RGP restores visual acuity. Another
solution includes the implementa-tion
of hybrid lenses. These consist of a gas
permeable rigid center sur-rounded by a
silicone hydrogel soft skirt. In fitting
this lens, the skirt is designed to lift
the rigid center off the corneal surface
so that it never has to interact with it.
However, there have been some
reported cases of warpage with these
lenses. 10 In addition, most, if not all of
the hybrid lenses do not offer enough
oxygen permeability to maintain ocular
health in the presence of a compromised
cornea. 10
LDRGP can also be considered.
due to tear film or other artifacts. 9
These surface issues contributed
to the decrease in best-corrected
visual acuity. Figure 1 shows
Axial Power map images at the
patient’s initial presentation.
The patient was diagnosed with
moderate hyperopia and astigma-
tism, requiring optical correction,
and bilateral neurotrophic kera-
topathy with scarring and irregular
corneal surfaces. Spectacles were
prescribed for full-time wear (for
distance, near and intermediate
activities) to provide an immediate
visual correction and to serve as a
back-up for contact lenses.
C a n a d i a n J o u r n a l
o f
Treatment plan
After the glasses were prescribed,
contact lenses were strongly recom-
mended as the primary treatment for
neurotrophic keratopathy. In this
condition, the ocular surface must be
protected to minimize the risk of
erosion; contact lenses help maintain
constant lubrication of the corneal
surface, which allows for its
restoration. A soft bandage does not
provide a good outcome for visual
correction on a highly irregular
cornea. Small diameter RGP lenses
can provide a better alternative to
improve visual acuity but do not
protect the ocular surface. In fact,
these lenses can increase mechanical
stress on an already altered cornea in
this case. One of the ways to
O p t o m e t r y | R e v u e
c a n a d i e n n e d
’ o p t o m é t r i e
They are fitted in a way to vault the
cornea. They maintain a constant
reservoir of fluid between the
lens and the cornea to ensure that
it remains lubricated. Moreover,
this fluid layer also compensates
for surface irregularities, leading to
improved visual acuity. This mo-
dality can provide the comfort of a
soft lens with the optical quality of
a gas permeable lens. In that way,
LDRGP designs currently available
are considered the best option to
provide health benefits and
increased comfort compared to
smaller corneal RGP and, in this
case, soft lenses. In the case of neu-
rotrophic keratopathy, in order to
determine which type of LDRGP to
use, any touch on the cornea should
be avoided. Corneo-scleral
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