Title: Satinder Pal Singh Grewal MD
1Safety and Efficacy of OculusGen Biodegradable
Collagen Matrix Implant in Phacotrabeculectomy
Surgery
Satinder Pal Singh Grewal MD Rajeev Jain, MD
Dilraj Grewal MBBS Gagandeep S Brar MD
GREWAL EYE INSTITUTE CHANDIGARH, INDIA
2Financial Disclosures
None of the authors have any financial interest
in this presentation
3Purpose
- To present the preliminary results of a pilot
study that evaluating the safety and efficacy of
OculusGen Biodegradable Collagen Matrix Implant
designed to improve the regenerating
tissue-remodeling in glaucoma patients with
cataract undergoing combined phacotrabeculectomy
surgery.
This study was registered with ClinicalTrials.gov
Identifier NCT00477685
4Introduction
- Long-term intraocular pressure (IOP) control
following trabeculectomy may be limited by
filtration failure, due to scarring at the level
of the conjunctiva-Tenons-episcleral interface,
the scleral flap or its overlying episclera, or
the internal ostium - Clinically, mitomycin-C (MMC), 5-fluorouracil,
and corticosteroids have all been used to inhibit
fibroblast proliferation to prevent scar
development after glaucoma surgery.However they
are associated with the risk for late
postoperative complications, including wound
leakage, hypotony, and maculopathy.1,2,3
- Sinnreich Z, Barishak R, Stein R. Leaking
filtering blebs. Am J Ophthalmol.
197886345349. - Stamper RL, McMenemy MG, Lieberman MF. Hypotonous
maculopathy after trabeculectomy with
subconjunctival 5-fluorouracil. Am J Ophthalmol.
1992114544553 - Sinnreich Z, Barishak R, Stein R. Leaking
filtering blebs. Am J Ophthalmol.
197886345349.
5Introduction
- The use of tissue bioengineering to prevent scar
prevention has been described.4,5,6,7 The
application of three-dimensional,
collagen-glycosaminoglycan copolymers can lead to
random and relatively loose reorganization of
regenerating myofibroblasts, fibroblasts, and the
secreted extracellular matrix (i.e., collagen),
reducing scar formation. - These biodegradable implants may simultaneously
provide physical resistance to overfiltration in
the early stages and progressively may reduce
this resistance as the implant degrades and a
random connective tissue matrix permeates the
spaces within the implant to create a loosely
organized bleb structure.
- Yannas IV, Lee E, Orgill DP, Skrabut EM, Murphy
GF. Synthesis and characterization of a model
extracellular matrix that induces partial
regeneration of adult mammalian skin. Proc Nat
Acad Sci USA. 198986933937. - Yannas IV. Studies on the biological activity of
the dermal regeneration template. Wound Repair
Region. 19986518524. - Chen HS, Ritch R, Krupin T, Hsu WC. Control of
filtering bleb structure through tissue
bioengineering An animal model.Invest Ophthalmol
Vis Sci. 2006 Dec47(12)5310-4. - Young MJ, Borras T, Walter M, Ritch R (2005)
Potential applications of tissue engineering to
glaucoma. Arch Ophthalmol 1231725173 - Hsu WC, Ritch R, Krupin T, Chen HS. Tissue
bioengineering for surgical bleb defects an
animal study. Graefes Arch Clin Exp Ophthalmol.
2008 Feb 12 Epub ahead of print
6StructureBiodegradable Collagen Matrix Implant
- In this study a three-dimensional biodegradable
collagen matrix was placed in the subconjunctival
space and on top of the scleral flap to achieve
better postoperative IOP control and to reduce
the risk for early shallow anterior chamber.
A drug-free, biodegradable, porous collagen
matrix of 1 collagen/C-6-S copolymer (OloGen)
with a 7-mm diameter and a 4-mm thickness was
used.
Scanning electron microscopic image of collagen
matrix.
7Methods
- 5 patients underwent combined trabeculectomy
with the OculusGen Biodegradable Collagen Matrix
Implant in one eye for refractory glaucoma - Refractory glaucoma was defined as having
previously failed medical, laser or surgical
treatment, and phacoemulsifcation with Acrylic
IOL impant (AMO AR-40). - The OculusGen was implanted on the top of the
scleral flap at the limbus before closing the
conjunctival wound during trabeculectomy
operations. - Intraocular pressure (IOP), bleb characteristics
and post-operative complications were assessed
before and after surgery. - Bleb photographs were analyzed at all
post-operative visits according to the Moorfields
Bleb-Grading System for the parameters of area
(grades 1-5), height (grades 1-4) and vascularity
(grades 1-5).
8Methods
Inclusion Criteria
Exclusion Criteria
- Known allergic reaction to porcine collagen.
- Subject is on warfarin and discontinuation is not
recommended. - Patients with
- Normal tension glaucoma,
- Uveitic glaucoma,
- Sphakic or pseudophakic glaucoma,
- Neovascular glaucoma
- Secondary glaucoma.
- Ocular infection within 14 days prior to
trabeculectomy. - Pregnant or breast-feeding women
- Age 30 years or older
- No previous intraocular surgery
- Uncontrolled glaucoma, with failed medical and
laser treatment, requiring trabeculectomy.
9Surgical Method of Implantation
Graphics from www.oculusgen.com
10Surgical Method of Implantation
- Positioning of implant in respect to the scleral
flap and the conjunctival wound. - Double arrow points to Conjunctival defect over
the area above the implant.
- Hsu WC, Ritch R, Krupin T, Chen HS. Tissue
bioengineering for surgical bleb defects an
animal study. Graefes Arch Clin Exp Ophthalmol.
2008 Feb 12 Epub ahead of print
Graphics from www.oculusgen.com
11Results
- The study population included 4 Males and 1
Female - Average age was 56.3 9.6 yrs
- The mean preoperative IOP was 35.7 7.8 mmHg.
- Postoperatively, the mean IOP at 4 months
follow-up for all eyes had a 54.3 reduction (p lt
0.05) to 16.3 2.1 mmHg. - There were no significant intra-operative or
post-operative complications in any patients.
12Conclusions
- The short-term preliminary results of this
study indicate that the OculusGen implantation in
combined phaco-trabeculectomy could potentially
provide a safe and effective therapeutic
preventing wound failure following trabeculectomy
surgery. - The OculusGen helps to modulate wound healing
response following glaucoma filtering surgery. - However a larger study with a longer follow-up
period is required to confirm these observations. - Biodegradable Collagen Matrix implants can help
in achieving a successful trabeculectomy without
antifibrotic medication,controlling both the
physical and physiologic aspects of wound
healing.