Biodegradable Collagen Matrix Research Articles

The Effect of a Triple Combination of Bevacizumab, Sodium Hyaluronate and a Collagen Matrix Implant in a Trabeculectomy Animal Model.

Currently available anti-scarring treatments for glaucoma filtration surgery (GFS) have potentially blinding complications, so there is a need for alternative and safer agents. The effects of the intrableb administration of a new combination of the anti-VEGF bevacizumab, sodium hyaluronate and a collagen matrix implant were investigated in a rabbit model of GFS, with the purpose of modulating inflammation, angiogenesis, fibroblast migration and fibrogenesis in the wound healing process. A comparative-effectiveness study was performed with twenty-four rabbits, randomly assigned to the following treatments: (a) biodegradable collagen matrix implant (Olo), (b) bevacizumab-loaded collagen matrix implant (Olo-BVZ), (c) bevacizumab-loaded collagen matrix implant combined with sodium hyaluronate (Olo-BVZ-H5) and (d) sham-operated animals (control). Rabbits underwent a conventional trabeculectomy and were studied over 30 days in terms of intraocular pressure and bleb characterization (height, area and vascularity in central, peripheral and non-bleb zones). Histologic differences among groups were further evaluated at day 30 (inflammation, total cellularity and degree of fibrosis in the area of surgery). Local delivery of bevacizumab (Olo-BVZ and Olo-BVZ-H5) increased the survival of the filtering bleb by 21% and 31%, respectively, and generated a significant decrease in inflammation and cell infiltration histologically 30 days after surgery, without exhibiting any local toxic effects. Olo-BVZ-H5 showed less lymphocyte infiltration and inflammation than the rest of the treatments. Intraoperative intrableb implantation of bevacizumab, sodium hyaluronate and a collagen matrix may provide an improved trabeculectomy outcome in this model of intense wound healing. This study showed an effective procedure with few surgical complications and a novel combination of active compounds that offer new possibilities to improve the efficacy of filtration surgery.

Application of biodegradable collagen matrix (Ologen\u2122) implants in Dacryocystorhinostomy surgeries, a randomized clinical study

BackgroundTo introduce and evaluate the application of Ologen implants in external Dacryocystorhinostomy (DCR) Surgeries.MethodsProspective comparative randomized study was carried out on 60 patients coming to ophthalmology department, Menoufia University Hospitals. Patients included were suffering from primary acquired nasolacrimal duct obstruction with positive regurge test. Patients were randomly enrolled into two groups using alternating choice technique. Group A included 30 patients who had DCR surgery to treat the obstruction with Silicone tubes. Group B included 30 patients had a Dacryocystorhinostomy with Silicone tubes and Ologen implants.ResultsSuccess rates as regard to relief of symptomatic epiphora were 86.7% in group A and 96.7% in group B and time of dye clearance test was 4.5 ± 0.6 min in group A and 3.9 ± 0.4 min in group B with p value 0.353 &0.001 consecutively. Apart from immediate mild post operative hemorrhage that was encountered in 2 cases in group B and 1 case in group A, there were no significant complications in both groups.ConclusionThe current study shows that application of Ologen implants in external DCR surgeries may improve symptomatic epiphora without exposing the patients to more intra-operative or post-operative complications. To the best of our knowledge, the current study is the first one to use Ologen implants in external DCR surgeries. However, the follow-up period was relatively short and the sample size is relatively small and further work is required to verify the effect of Ologen in external DCR surgeries.Trial registrationCurrent Controlled Trials PACTR201711002809215, and the date of registration is 29 November 2017. The trial is Retrospectively registered.

Efficacy of collagen matrix implant on adhesions in restrictive strabismus: An experimental study in a rabbit model.

To determine the efficacy of a biodegradable collagen matrix implant (Ologen, Aeon Astron Europe BV, Leiden, the Netherlands) in reducing adhesions in a rabbit model of restrictive strabismus. A prospective, masked-observer, controlled experimental study was performed. Sixty superior rectus muscles of 30 rabbits were resected and Marlex mesh was fixed beneath the resected muscle using nonabsorbable suture. Forty eyes underwent one of two different procedures; the resected muscle was wrapped with preserved human amniotic membrane (AM group) or Ologen (Ologen group). Randomly selected 20 eyes served as controls. Eyes were enucleated at 4weeks after surgery to measure the severity of adhesion using a push pull gauge. Histopathological examination was performed. At postoperative week four, the average tensile strength of the myoscleral adhesion was significantly lower in the Ologen group (151.8±42.7 gram force) compared to controls (347.9±68.6 gram force) and AM group (193.0±44.3 gram force) (p<0.001 and p=0.045, respectively). Ologen group showed significantly lower degree of acute inflammation, chronic inflammation and rectus muscle fibrosis compared with controls (all p<0.01). The degree of chronic inflammation was significantly lower in the Ologen group compared with AM group (p=0.012). Compared to amniotic membrane, Ologen is more effective in reducing mesh-related extraocular muscle adhesions in a rabbit model of restrictive strabismus.

Conjunctival Flap with Biodegradable Collagen Matrix Implantation for the Treatment of Scleromalacia after Periocular Surgery

ABSTRACTPurpose: To report a new surgical procedure using biodegradable collagen matrix (Ologen) implantation with conjunctival flap for reconstruction of scleromalacia after periocular surgery.Methods: A total of 26 areas of 25 eyes in 25 patients were included. We divided all eyes according to the preoperative extent of calcified plaque or scleral defect as follows: small, large, and large and severe. Morphologic outcomes were graded from 0 to 7, with higher scores indicating worse cosmetic outcomes.Results: Mean follow-up period was 8.3 ± 5.6 months. No eyes showed recurrence or specific complications related to Ologen such as implant extrusion or allergic reaction. Minor complications such as flap vessel engorgement and flap hypertrophy were easily treated. Mean morphologic outcome scores were 1.8, 2.4, and 5.3 in groups 1, 2, and 3, respectively.Discussion: The combined surgery may be an effective and safe procedure for the treatment of scleromalacia after periocular surgeries.

Glaucoma surgery: from traditional filtration techniques to modern principles of bioengineering

The article reviews the history of glaucoma surgery and analyses the connection between the accumulation of knowledge on glaucoma progression and the emergence of effective surgical treatment methods based on glaucoma pathogenesis. It also describes modern principles of preventing filtering bleb scarring. Particular attention is devoted to biodegradable collagen matrix implants.

Outcome of adding collagen matrix implant (Ologen) to Trabeculectomy–Trabeculotomy operation with MMC for primary congenital glaucoma

Purpose To study the value of adding collagen matrix (CM) to the surgical procedure combined trabeculotomy-trabeculectomy with mitomycin C (CTTM) for the treatment of Primary congenital glaucoma (PCG). Patients and methods Fourty eyes were operated upon. The CM was inserted under the scleral and conjunctival flaps. Follow up was for 6 -12months Results At 6 months; all eyes manifested full success. At 1 year; one eye manifested poor success. There were minimal complications in the form of intraoperative hyphema, vitreous loss and postoperative shallow anterior chamber, immunological reaction and thin avascular cystic blebs. Conclusion This study is novel in using both MMC and CM implant at the same time for augmentation of CTT procedure with highest success ever reported for PCG. Biodegradable CM markedly increased the short and long term surgical success with marked reduction of complications.

Trabeculectomy Combined With Collagen Matrix Implant (Ologen).

The purpose of the study was to report and evaluate outcomes of trabeculectomy with use of a subconjunctival biodegradable collagen matrix implant. Retrospective review of trabeculectomy with Ologen implant of 65 eyes of 58 patients by the same surgeon from October, 2011 to October, 2014. Exclusion criteria were <6 months of follow-up after surgery, and uveitic or neovascular glaucoma. Demographic characteristics of the study population, visual acuity, intraocular pressure (IOP), glaucoma medications, bleb characteristics, and early and late postoperative complications were recorded. Complete and qualified IOP control success, ≤15 and ≤18 mm Hg, was calculated with the Kaplan-Meier analysis. The mean age of the patients in the study was 65.9±15.1 years. IOP was reduced from a mean of 21.4±9.2 to 12.3±3.7 mm Hg at the last follow-up visit (P<0.0001). The number of IOP-lowering medications per eye was reduced from a mean of 1.86 preoperatively to 0.2 at the last follow-up visit (P<0.0001). The Kaplan-Meier survival curves of complete success for IOP≤15 mm Hg and ≤18 mm Hg were 47.2% and 62.9%, respectively, at 36 months. Postoperative complications occurred in 15% of the eyes, with bleb leakage (6%) and hypotony (5%), which were resolved medically. At the last postoperative visit, blebs were described as normal (86.4%), flat (9.1%), and polycystic (4.5%). Trabeculectomy surgeries with Ologen performed by the same surgeon were effective in lowering IOP with a low complication rate at mid-term follow-up.

Safety and efficacy of collagen matrix implantation in infantile glaucoma.

To evaluate the preliminary results of biodegradable collagen matrix implant (Ologen) designed to improve outcome in patients with infantile glaucoma undergoing combined trabeculotomy and trabeculectomy. A biodegradable collagen matrix (OculusGen) was placed in the subconjunctival space, partially over the scleral flap and the sclera in 20 eyes of 11 patients with infantile glaucoma who underwent combined trabeculotomy and trabeculectomy. Patients were examined preoperatively and on the first postoperative day with multiple postoperative follow-up visits within 12 months after surgery. Examination included measurements of intraocular pressure (IOP), corneal diameter, and axial length, bleb evaluation, and funduscopy. Ultrasound biomicroscopy of bleb (bleb presence, wall reflectivity, and scleral route visibility) was done at 1, 3, and 6 months and the last follow-up visit. Any complication was recorded. Data analysis was performed using paired-samples t test. Mean patient age was 5.7 ± 5.69 months. Mean duration of follow-up was 10.05 ± 1.15 months. Mean preoperative IOP was 25.9 ± 3.08 mm Hg with 1.75 ± 0.55 IOP-lowering medications and mean final postoperative IOP was 17.7 ± 3.51 mm Hg with 0.55 ± 0.69 IOP-lowering medications. Overall success at last follow-up was 80%. None of the patients experienced systemic or ocular complication related to OculusGen. By the 6th month, complete Ologen degradation was evident in all cases. The short-term preliminary results of this study indicate that the combined trabeculotomy and trabeculectomy with Ologen implantation could potentially provide a safe and effective procedure in the infantile age group but longer duration of follow-up in larger number of patients is needed.

A Comparative Analysis of Outcomes of Pterygium Surgery with or without Collagen Matrix Implantation

Background: Pterygium is a common disorder in many parts of the world, with reported prevalence rates ranging from 0.3 to 29%. Epidemiological studies have proposed an association with chronic exposure to sunlight and an increased geographical prevalence within a peri-equatorial ‘pterygium belt’ region (1). Pterygium excision is often combined with various adjunctive measures to prevent its recurrence, however recurrenece is still the most common post-surgical complication. Numerous techniques have been attempted to reduce localized fibrovascular activity and the overall rate of recurrence; these include, β-irradiation, conjunctival and limbal auto-grafting, antimitotic drugs and amniotic membrane transplantation (2). In recent years, a novel bioengineered product has been advocated for preventing recurrence and has shown promising outcomes in animal models This study was conducted to compare the effect of collagen matrix implant with conjunctival autograft following pterygium surgery (treatment group) with only conjunctival autograft following pterygium surgery (control group). Methods: Following informed consent, sixty eyes of 60 patients (females = 23, males =37, aged 23–67 years) were randomly allocated into two equal groups. Pterygia of all patients were excised and conjunctival autograft was done. However, for patients in the treatment group a 1×3 mm collagen matrix graft (Ologen) was implanted subconjunctivally under the graft. Patients were followed up for six months. The parameters studied were patient comfort, foreign body sensation, dellen formation, pterygium recurrence and time for absorption of the collagen matrix. Results: Results revealed that no eyes in the control group and one eye in the intervention group developed recurrence; dellen formation not was observed in any patient in both groups. Patient comfort and foreign body sensation did not differ significantly in both groups. Three eyes in treatment group developed a tenon’s cyst. In 12 out of 30 eyes, the collagen matrix was not absorbed at six months post surgery. Conclusion: In conclusion, the use of biodegradable collagen matrix implants (Ologen) following pterygium excision did not seem to be associated with a lower risk of recurrence. Moreover, tenon’s cyst formation and persistence of the matrix subconjunctivally was observed. Further studies with adequate sample size are recommended for more comprehensive conclusion.

Biodegradable collagen matrix (Ologen™) implant and conjunctival autograft for scleral necrosis after pterygium excision: two case reports

BackgroundScleromalacia, in the form of scleral thinning, melting, and necrosis, is a potentially serious complication of pterygium excision. This study introduces a new biodegradable material, Ologen™ collagen matrix (OCM), to repair scleral thinning as an alternative to preserved scleral tissue, and evaluates the long-term outcomes of OCM for ocular surface reconstruction surgery.Case presentationTwo cases of possibly mitomycin C (MMC)-associated marked scleral thinning after pterygium excision with 0.02 % topical MMC for 2-weeks were included in this study. An OCM graft at the scleral thinning area and conjunctival autograft (CAU) were performed on both patients. The scleral defect size was measured and its margin was marked with a biopsy punch. The margin of the scleral thinning area was trimmed by Vannas scissors and the OCM was cut using a circular-shape biopsy punch of the same size. The OCM was sutured with a recipient scleral wall using 10–0 nylon interrupted sutures. Free CAU was harvested from the superonasal bulbar conjunctiva with a punch biopsy 1-mm larger in diameter than that of the OCM. The previously sutured OCM bed was covered with CAU and the graft was secured with 10–0 nylon interrupted sutures. Both patients were examined periodically for over two years by assessing graft thickness and surface vascularization using a slit lamp biomicroscope. Reepithelialization of the ocular surface was observed within three to six days after surgery. Ocular discomfort and inflammation ceased in both patients as the ocular surface quickly stabilized. The entire graft site remained intact and provided a good healthy ocular surface with fluorescein stain negative intact epithelium and good vascularization of grafted conjunctiva. Epithelial defects and scleral thinning did not recur in either patient over the two year follow-up period.ConclusionFor treatment of a possibly MMC-associated scleral necrosis following the surgical excision of the pterygium, an OCM graft with CAU is highly recommended for good clinical outcomes and low recurrence rates. With the clinical results of this study, the new biodegradable Ologen™ collagen matrix qualifies as an alternative treatment to scleral tissue for ocular surface reconstruction.

Bleb Analysis and Short-Term Results of Biodegradable Collagen Matrix-Augmented Ahmed Glaucoma Valve Implantation: 6-Month Follow-up.

To evaluate the short-term efficacy of a biodegradable collagen matrix (BCM) as an adjuvant for Ahmed valve implantation surgery to prevent the hypertensive phase. This prospective study included 43 refractory glaucoma eyes, all followed for 6 months. Refractory glaucoma was defined as an IOP higher than 20 mm Hg with antiglaucoma eye drops without previous glaucoma surgery. Conventional method was performed in 21 eyes and BCM-augmented Ahmed valve implantation (BAAVI) in 22 eyes. In the BAAVI group, a 10 × 10 × 2-mm BCM was sutured on an Ahmed glaucoma valve FP7 model. Complete success was defined as an IOP of 21 mm Hg or lower (target IOP 1) or 17 mm Hg or lower (target IOP 2) without antiglaucoma medications and qualified success as an IOP of 21 mm Hg or lower with or without medications. Maximal bleb thickness was measured using anterior segment optical coherence tomography images. The preoperative IOPs and numbers of preoperative antiglaucoma medications were similar for both groups. Complete target IOP 1 success rates were 38.1% and 86.4%, complete target IOP 2 success rates were 19.0% and 59.1%, and qualified success rates were 52.4% and 90.9% in the conventional and BAAVI groups, respectively (P < 0.05). The hypertensive phase rate was lower in the BAAVI group (4.5% vs. 47.6%, P = 0.002). Maximal bleb thickness was increased in the BAAVI group on postoperative days 30 and 180 (P < 0.05). Success rates were higher in the BAAVI group than in the conventional group with the change of bleb morphology. Furthermore, use of BCM significantly decreased the need for antiglaucoma medications for at least 6 months postoperatively.

Scleral Repair by Biodegradable Collagen Implant in Strabismus Surgery

Aim: To evaluate biodegradable collagen implant as a patch for scleral defect . Case Presentation : A 3 years old girl was subjected to scleral rupture during lateral rectus (LR) advancement for correc tion of consecutive esotropia. A scleral defect accidentally occurred with uveal exposure of an area 4x6 mm posterior to the original insertio n of the lateral rectus muscle The defect was covered by a patch of biodegradable colla gen matrix (CM) implant Ologen™ ( Aeon Astron Europe B.V., Leiden, The Nethe rlands) measuring 12 mm diameter x 1mm thickness. Conjunctiva was meticulously closed over it. A follow up of 1 year was performed regarding ocular alignment and globe integrity which was assessed by slit lamp, fundus examination, photography and B - scan ultrasonography (U/S). Results: Both eyes remained aligned . Scleral defect was well covered, healed by the collagen implant which was incorporated in the surrounding scleral tissues . During postoperative fol low up, no uveal exposure and intact retina (no retinal breaks) were detected. Discussion and Conclusion: Scleral rupture is a potential serious problem that can be managed by patching with collagen matrix biodegradable implant before closing the conjunctiva.

Surgical Outcome of Mitomycin C-soaked Collagen Matrix Implant in Trabeculectomy

To assess the surgical outcomes and wound healing reaction of a filtering bleb after trabeculectomy using mitomycin C-soaked biodegradable collagen matrix (ologen). Thirty eyes, in which the intraocular pressure (IOP) could not be controlled within the proper range by medication or laser treatment, were targeted in this study. After trabeculectomy with mitomycin C (0.2 mg/mL, 0.1 mL)-soaked ologen, surgical outcomes were assessed by evaluating bleb morphology by the Moorfield bleb grading system, as well as internal reflectivity and wound healing response of the bleb using a slit lamp and ultrasound biomicroscopy. The follow-up period continued for 12 months after surgery. Twelve months after surgery, 12/30 (40.0%) eyes were considered complete successes and 24/30 (80%) eyes as qualified successes. This rate is similar to the rate of our conventional trabeculectomy. The encapsulated bleb was the most frequent complication (9 eyes) and generally occurred at approximately 2 weeks after surgery. No avascular blebs were observed at final follow-up. Trabeculectomy with mitomycin C-soaked ologen do not seem to exert any synergistic effect with antimetabolites in terms of a reduction in IOP. However, the mitomycin C-soaked collagen matrix implant used in trabeculectomy resulted in comparatively stable IOP and did not aggravate wound healing or scar formation. Encapsulated blebs were generated at a more rapid pace in larger amounts compared with conventional trabeculectomy. The management of encapsulated blebs may be crucial to improving the success rate of surgery.

The Analysis of the Clinical Findings and Effects of Biodegradable Collagen Matrix in Trabeculectomy

The Analysis of the Clinical Findings and Effects of Biodegradable Collagen Matrix in Trabeculectomy

Biodegradable collagen matrix implant vs mitomycin-C as an adjuvant in trabeculectomy: a 24-month, randomized clinical trial

Biodegradable collagen matrix implant vs mitomycin-C as an adjuvant in trabeculectomy: a 24-month, randomized clinical trial

Biodegradable collagen matrix implant vs mitomycin-C as an adjuvant in trabeculectomy: a 24-month, randomized clinical trial

To verify the safety and efficacy of Ologen (OLO) implant as adjuvant compared with low-dosage mitomycin-C (MMC) in trabeculectomy. This was a prospective randomized clinical trial with a 24-month follow-up. Forty glaucoma patients (40 eyes) were assigned to trabeculectomy with MMC or OLO. Primary outcome includes target IOP at ≤21, ≤17, and ≤15 mm Hg; complete (target IOP without medications), and qualified success (target IOP regardless of medications). Secondary outcomes include bleb evaluation, according to Moorfields Bleb Grading System (MBGS); spectral domain optical coherence tomography (SD-OCT) examination; number of glaucoma medications; and frequency of postoperative adjunctive procedures and complications. The mean preoperative IOP was 26.5 (±5.2) in MMC and 27.3 (±6.0) in OLO eyes, without statistical significance. One-day postoperatively, the IOP dropped to 5.2 (±3.5) and 9.2 (±5.5) mm Hg, respectively (P=0.009). The IOP reduction was significant at end point in all groups (P=0.01), with a mean IOP of 16.0 (±2.9) and 16.5 (±2.1) mm Hg in MMC and OLO, respectively. The rates and Kaplan-Meier curves did not differ for both complete and qualified success at any target IOP. The bleb height in OLO group was higher than MMC one (P<0.05). SD-OCT analysis of successful/unsuccessful bleb in patients with or without complete success at IOP ≤17 mm Hg indicated a sensitivity of 83% and 73% and a specificity of 75% and 67%, respectively, for MMC and OLO groups. No adverse reaction to OLO was noted. Our results suggest that OLO implant could be a new, safe, and effective alternative to MMC, with similar long-term success rate.

Biodegradable collagen matrix subconjunctival implant (Oculusgen®), our experience in pterygium surgery

Biodegradable collagen matrix subconjunctival implant (Oculusgen®), our experience in pterygium surgery

Fibrous Encapsulation of Biodegradable Collagen Matrix After Trabeculectomy: A Case Report

Purpose: Recently, biodegradable collagen matrix has been used as a possible substitute for anti-metabolite in trabeculectomy in order to control the responsiveness of the wound healing process. This paper reports a case of encapsulation of the biodegradable collagen matrix after trabeculectomy. Case summary: We conducted a fornix-based trabeculectomy on a 58-year-old man with medically uncontrollable steroid-induced glaucoma. We implanted biodegradable collagen matrix onto the sclera flap beneath the conjunctiva. Immediately after the surgery, we observed a localized bleb with high elevation. In the three months of follow-up, the bleb became encapsulated, and an increase in intraocular pressure was noted. During the wound revision, encapsulated material surrounded by thick fibrous membrane was found and removed from the subconjunctival space, followed by biopsy. Biopsy results demonstrated that amorphous collagenous material was surrounded by spindle and inflammatory cells. Conclusions: It is important to note that the fibrous encapsulation of collagen material is a possible complication of biodegradable collagen matrix-augmented trabeculectomy.

Trabeculectomy With Biodegradable Collagen Material: A Report of Two Cases

Purpose: To report two cases of trabeculectomy with biodegradable collagen material conducted on two post-vitrectomy patients. Case summary: The first patient was a 43-year-old woman with uncontrolled increased intraocular pressure (IOP) after pars plana vitrectomy with scleral buckling for diabetic retinopathy and vitreous hemorrhage. Another patient, a 28-year-old woman with aphakia, also had uncontrolled increased IOP after pars plana vitrectomy with encircling scleral buckling for retinal detachment. For both of these patients, we performed trabeculectomy using mitomycin C and recently developed biodegradable collagen matrix. In the first case, the IOP was increased three months after the surgery, for which needling was done. After needling, the IOP was well controlled in the range of 16 to 19 mmHg up to eight months postoperatively with stilling anti-glaucomatous eyedrops (Cosopt, Xalatan). In the second case, IOP was increased one week after the surgery, but it was well controlled between 14 to 21 mmHg up to nine months postoperatively with anti-glaucomatous eye drops (Combigan). Conclusions: Biodegradable collagen matrix can possibly reduce the surgical failure of trabeculectomy and it is especially suitable for high risk patients when combined with anti-metabolic agents like MMC.

Biodegradable collagen matrix implant for trabeculectomy

The biodegradable collagen matrix implant, marketed initially as OculusGen™ and currently as Ologen™ and iGen™, is a novel bioengineered implant designed to be used at the time of trabeculectomy. It consists of a collagen-based scaffold containing thousands of microscopic pores. The implant is placed directly over the scleral flap and influences the healing process by forcing fibroblasts and myofibroblasts to grow into the pores and secrete connective tissue in the form of a loose matrix. This results in decreased scar formation and improved surgical success over trabeculectomy performed without the adjunctive use of antifibrotic agents. Preliminary studies have demonstrated that the biodegradable collagen matrix is effective for use in trabeculectomy, although it may be associated with an increased risk of early postoperative hypotony. Future randomized, controlled trials should help determine its place in glaucoma surgery.