Transcript Document

Safety 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
v
GREWAL EYE INSTITUTE
CHANDIGARH, INDIA
Financial Disclosures
None of the authors have any financial interest in this
presentation
v
Purpose
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.
v
This study was registered with ClinicalTrials.gov: Identifier NCT00477685
Introduction
Long-term intraocular pressure (IOP) control following trabeculectomy may
be limited by filtration failure, due to scarring at the level of the conjunctivaTenon’s-episcleral interface, the scleral flap or its overlying episclera, or the
internal ostium
v
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
1. Sinnreich Z, Barishak R, Stein R. Leaking filtering blebs. Am J Ophthalmol. 1978;86:345–349.
2. Stamper RL, McMenemy MG, Lieberman MF. Hypotonous maculopathy after trabeculectomy with subconjunctival 5-fluorouracil. Am J Ophthalmol.
1992;114:544–553
3. Sinnreich Z, Barishak R, Stein R. Leaking filtering blebs. Am J Ophthalmol. 1978;86:345–349.
Introduction
The use of tissue bioengineering to prevent scar prevention has been
described.4,5,6,7 The application of three-dimensional, collagenglycosaminoglycan 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.
v
4.
5.
6.
7.
8.
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. 1989;86:933–937.
Yannas IV. Studies on the biological activity of the dermal regeneration template. Wound Repair Region. 1998;6:518–524.
Chen HS, Ritch R, Krupin T, Hsu WC. Control of filtering bleb structure through tissue bioengineering: An animal model.Invest Ophthalmol Vis Sci. 2006
Dec;47(12):5310-4.
Young MJ, Borras T, Walter M, Ritch R (2005) Potential applications of tissue engineering to glaucoma. Arch Ophthalmol 123:1725–173
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]
Structure:Biodegradable 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.
v
Scanning electron microscopic image of collagen matrix.
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.
Methods
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.
v
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).
Methods
Inclusion Criteria:
•Age 30 years or older
•Known allergic reaction to porcine collagen.
•No previous intraocular surgery
•Subject is on warfarin and discontinuation is not
•Uncontrolled glaucoma, with failed
recommended.
medical and laser treatment, requiring
v
Exclusion Criteria:
trabeculectomy.
•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
Surgical Method of Implantation
v
Graphics from www.oculusgen.com
Surgical Method of Implantation
v
•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.
1. 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
Results
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.
v
Postoperatively, the mean IOP at 4
months follow-up for all eyes had a
54.3% reduction (p < 0.05) to 16.3
±2.1 mmHg.
There were no significant intraoperative or post-operative
complications in any patients.
Conclusions
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.
v
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.