Transcript Assessing the Role of Soft Contact Lenses in Preoperative

Assessing the Role of Soft Contact Lenses
in Preoperative Conditions Following
Keratoprosthesis Implantation
Leah L. Kammerdiener, Miranda Lynch, Mona Harissi-Dagher,
Claes H. Dohlman, James Aquavella, Joseph B. Ciolino, James Chodosh
Massachusetts Eye and Ear Infirmary, University of Rochester Flaum Eye Institute
The authors have no financial interest in the subject matter of this poster.
INTRODUCTON
The keratoprosthesis (Kpro), an artificial cornea, has proven
effective at establishing a clear pathway for light through an
opaque cornea.1 To qualify for the procedure, patients who
underwent KPro surgery had poor prognoses for simple
penetrating keratoplasty. These included patients with multiple
graft rejection (54%), chemical injury (15%), and herpes simplex
virus keratitis (7%) among others.2 The quality of life of the
patients was increased with the restoration of vision, in some
cases from light perception only to 20/400 vision1.
Some of the difficulties arising from the KPro surgery have been
desiccation by evaporative forces, epithelial defects, stromal
thinning, and dellen formation.3 Problems caused by the physical
presence of the device include instability of the KPro and
aqueous humor leakage.4 To help protect the cornea from some
of these complications, a soft contact lens (SCL) is routinely
placed as the last step of surgery.3 The lens protects the corneal
surface by diffusing the evaporative forces and maintaining a
fluid meniscus at the edge of the front plate of the KPro. It also
corrects postoperative refractive error, and can be used for
cosmetic effect to match its paired eye.3,5,6
Photos: Keratoprosthesis with overlying soft contact lens on slit lamp exam
It has been recognized that pre-operative categories of patients,
most broadly divided into autoimmune disorders, chemical injury,
and “other” can be prognostic of post-surgical visual acuity
outcomes.7 For the purposes of this study, the preoperative
conditions have been grouped into autoimmune (StevensJohnson Syndrome, ocular cicatricial pemphigoid, rheumatoid
arthritis, and uveitis), chemical injury, and “other” (infection and
non-inflammatory conditions such as dystropheis, trauma,
keratopathies, and keratoconus). There is however, a scarcity of
data evaluating the pre-operative groups for prognostic value in
the management of post-operative SCL use and complications.
PURPOSE
To evaluate associations between patient pre-operative diagnosis
with SCL retention, complications, and outcomes.
METHODS
A retrospective chart review was conducted of 92 patients’ (103 eyes)
charts who underwent a Boston KPro Type I at the Massachusetts
Eye and Ear Infirmary (MEEI) or the University of Rochester Flaum
Eye Institute (UREI) by one of two surgeons (J.V.A, or C.H.D)
between August 1995 and June 2008. The medical records were
reviewed and analyzed for pre-operative diagnosis, past ocular
surgical history, SCL retention, and subsequent complications and
outcomes.
RESULTS
• Preoperative categories included 16 patients with autoimmune
disease (Stevens Johnson Syndrome, ocular cicatritial pemphigoid,
rheumatoid arthritis, and uveitis), 9 with chemical injury, and 67
“other” (aniridia, infection, trauma, dystrophies, and keratopathies).
Figure: Time (in months) until first soft
contact lens loss in each preoperative
group. Vertical dashes mark where a
censored data point occurs (time when
patient follow-up ended, but no SCL loss
was experienced).
•
Among these groups, the time to first soft contact lens (SCL) loss
was shortest for chemical injury and longest for autoimmune
patients.
• Chemical injury had more SCL losses while autoimmune had fewest.
• A small subset (n=17) of the population experienced more than 2
SCL losses per year. These patients comprised 6% of the
autoimmune group, 22% of the chemical injury group, and 21% of
the “other” group.
Soft Contact Lens Losses By Preoperative Diagnosis
30
25
Figure: Number of soft contact lens
(SCL) losses per 10 years SCL
wear.
20
15
10
5
0
1
Autoimmune
Chemical Injury
Other
• Autoimmune experienced the highest yearly complication rate and
“other” the lowest rate.
• Among all three categories, complication rates were highest when
patients were not wearing their contact lenses. The most common
complication experienced was corneal melt resulting in aqueous
humor leak.
• Patients over the age of 70 years were significantly less likely to
experience a complication compared to those younger than 70.
Complications By Preoperative Diagnosis
6
Figure: Number of complications
experienced while wearing SCL
and without SCL per 10 patientyears of follow-up.
5
Number of
Complications with SCL
(per 10 patient-years)
4
3
Number of
Complications without
SCL (per 10 patientyears)
2
1
0
Autoimmune
Chemical Injury
Other
CONCLUSION
• Even with a trend toward higher lens retention, some patients with
autoimmune disease are destined to develop corneal complications
after implantation. The chronic inflammatory response present in
eyes affected by autoimmune diseases is responsible for increased
complication rates, predisposing the corneal surface to sterile
corneal ulcers and infections.6
• Chemically injured eyes experienced the most rapid initial soft
contact lens loss which may be due to poor tear production, ocular
surface disease, symblepharon formation, and lid abnormalities that
are associated with these injuries.8
• Non-autoimmune and non-chemical injury patients may have less
inflammation, and typically have normal tear production and normal
eyelid function. The difficulty in lens fitting in some non-chemical
injury and non-autoimmune disorder patients may account for the
slightly higher rate of contact lens loss.
REFERENCES
1 Aquavella, JV., Y. Qian, GJ. McCormick, and JR. Palakuru. "Keratoprosthesis: The Dohlman-Doane
Device." American Journal of Ophthalmology 6 (2005): 1032-038.
2 Zerbe, B., M. Belin, and J. Ciolino. "Results from the Multicenter Boston Type 1 Keratoprosthesis
Study." Ophthalmology 113 (2006): 1779-784.
3 Harissi-Dagher, M., J. Beyer, and CH. Dohlman. "The Role of Soft Contact Lenses as an Adjunct to
the Boston Keratoprothesis." International Opthalmology Clinic 2 (2008): 43-51.
4 Khan, BF., M. Harissi-Dagher, DM. Khan, and CH. Dohlman. "Advances in Boston Keratoprosthesis:
Enhancing Retention and Prevention of Infection and Inflammation." International
Ophthalmology Clinic 2 (2007): 61-71.
5 Macsai, MS. "The Management of Corneal Trauma: Advances in the Past Twenty-five Year." Cornea
5 (2000): 617-24.
6 Dohlman, CH., EJ. Dudenhoefer, BF. Khan, and S. Morneault. "Protection of the Ocular Surface
After Keratoprosthesis Surgery: The Role of Soft Contact Lenses." CLAO J. 2 (2002): 72-74.
7 Yaghouti, F., M. Nouri, JC. Abad, WJ. Power, MG. Doane, CH. Dohlman.
“Keratoprothesis: Preoperative Prognostic Categories.” Cornea 20 (2001): 19-23.
There are no commercial relationships or any financial disclosures.
8 Kadar T, Dachir S, Cohen L, et al. Ocular injuries following sulfur mustard exposure--pathological
mechanism and potential therapy. Toxicology. Sep 1 2009;263(1):59-69.