Subconjunctival High Dose Plasminogen Activator in Rabbit Filtration Surgery

Abstract

The primary cause of failure in glaucoma filtration surgery is fibroblastic proliferation and subconjunctival fibrosis at the bleb site resulting in decreased aqueous flow. We evaluated New Zealand white rabbits in a masked, placebo controlled pilot study to determine the potential reduction of episcleral fibrosis at the surgical bleb site utilizing 0.3 mis of: balanced salt solution (n = 11); an Inert gel delivery vehicle (n=13); the gel delivery vehicle with incorporated recombinant tissue plasminogen activator (tpa; n=14), 1 mg/ml. Statistical analysis of computer assisted area measurements from multiple histologie sections demonstrated a significant decrease in episcleral fibrosis in the t-PA group as compared to the two other groups (p < 0.05). Results from the t-PA group did not demonstrate an effect on intraocular pressure. There was no clinical evidence of toxicity or healing complications in the t-PA group. 9

Biocompatibility and feasibility of VisiPlate, a novel ultrathin, multichannel glaucoma drainage device

“…Comparatively, XEN and Ahmed glaucoma devices showed decreases in IOP in the 15-40% range, with notes of needing revision surgery to optimize impact [19,23,25,26]. In other literature, glaucoma filtration surgeries tend to fail, and IOP rises, within 2-3 weeks [27,28], while glaucoma drainage devices fail at 3-6 weeks [29,30]. It is also important to note the peak IOP found at 120 days.…”

Biocompatibility and feasibility of VisiPlate, a novel ultrathin, multichannel glaucoma drainage device

“…Comparatively, XEN and Ahmed glaucoma devices showed decreases in IOP in the 15-40% range, with notes of needing revision surgery to optimize impact [19,23,25,26]. In other literature, glaucoma filtration surgeries tend to fail, and IOP rises, within 2-3 weeks [27,28], while glaucoma drainage devices fail at 3-6 weeks [29,30]. It is also important to note the peak IOP found at 120 days.…”

Foreign Body Reaction in Glaucoma Drainage Implant Surgery

“…The rabbit has been shown to be an aggressive wound healing response, such that glaucoma filtration surgeries in rabbits fail within 2 to 3 weeks postoperatively in rabbits due to aggressive wound healing at the surgical site. 20,21 Regarding glaucoma drainage device implantation, Jacob et al 22,23 documented that rabbits developed fibrous encapsulation and maintained functioning blebs for more than 3 to 6 weeks after Baerveldt drainage device implantation. They found that the fibrous capsule thickness was thinner, and the amount of type III collagen was less in the modified implants with porous cellular ingrowth material to the drainage plate or 5-fluorouracil treatment.…”

“…The rabbit has been considered as a useful model for evaluating histopathology or clinical outcome in glaucoma surgery. [20][21][22][23]27,28 In addition, it has been known that there are little difference in protein distribution between human and rabbit aqueous humor. 29 Therefore, we believe that our findings may apply to humans to a certain extent.…”

Induction and Mechanism of Apoptosis by Hydroxycamptothecin in Human Tenon's Capsule Fibroblasts

“…However, the reported failure rate is approximately 15% to 30%. [4][5][6] The main reason for surgical failure is the proliferation of fibroblasts leading to scarring of the channel in the filtration area. To control postoperative scarring, antiproliferative agents, such as mitomycin C or 5-fluorouracil, are used to prevent fibroblast growth and scar formation.…”

Biocompatibility and feasibility of VisiPlate, a novel ultrathin, multichannel glaucoma drainage device

“…Comparatively, XEN and Ahmed glaucoma devices showed decreases in IOP in the 15-40% range, with notes of needing revision surgery to optimize impact [19,23,25,26]. In other literature, glaucoma filtration surgeries tend to fail, and IOP rises, within 2-3 weeks [27,28], while glaucoma drainage devices fail at 3-6 weeks [29,30]. It is also important to note the peak IOP found at 120 days.…”

Foreign Body Reaction in Glaucoma Drainage Implant Surgery

“…The rabbit has been shown to be an aggressive wound healing response, such that glaucoma filtration surgeries in rabbits fail within 2 to 3 weeks postoperatively in rabbits due to aggressive wound healing at the surgical site. 20,21 Regarding glaucoma drainage device implantation, Jacob et al 22,23 documented that rabbits developed fibrous encapsulation and maintained functioning blebs for more than 3 to 6 weeks after Baerveldt drainage device implantation. They found that the fibrous capsule thickness was thinner, and the amount of type III collagen was less in the modified implants with porous cellular ingrowth material to the drainage plate or 5-fluorouracil treatment.…”

“…The rabbit has been considered as a useful model for evaluating histopathology or clinical outcome in glaucoma surgery. [20][21][22][23]27,28 In addition, it has been known that there are little difference in protein distribution between human and rabbit aqueous humor. 29 Therefore, we believe that our findings may apply to humans to a certain extent.…”

Induction and Mechanism of Apoptosis by Hydroxycamptothecin in Human Tenon's Capsule Fibroblasts

“…However, the reported failure rate is approximately 15% to 30%. [4][5][6] The main reason for surgical failure is the proliferation of fibroblasts leading to scarring of the channel in the filtration area. To control postoperative scarring, antiproliferative agents, such as mitomycin C or 5-fluorouracil, are used to prevent fibroblast growth and scar formation.…”

Biocompatibility and feasibility of VisiPlate, a novel ultrathin, multichannel glaucoma drainage device

“…Comparatively, XEN and Ahmed glaucoma devices showed decreases in IOP in the 15-40% range, with notes of needing revision surgery to optimize impact [19,23,25,26]. In other literature, glaucoma filtration surgeries tend to fail, and IOP rises, within 2-3 weeks [27,28], while glaucoma drainage devices fail at 3-6 weeks [29,30]. It is also important to note the peak IOP found at 120 days.…”

Foreign Body Reaction in Glaucoma Drainage Implant Surgery

“…The rabbit has been shown to be an aggressive wound healing response, such that glaucoma filtration surgeries in rabbits fail within 2 to 3 weeks postoperatively in rabbits due to aggressive wound healing at the surgical site. 20,21 Regarding glaucoma drainage device implantation, Jacob et al 22,23 documented that rabbits developed fibrous encapsulation and maintained functioning blebs for more than 3 to 6 weeks after Baerveldt drainage device implantation. They found that the fibrous capsule thickness was thinner, and the amount of type III collagen was less in the modified implants with porous cellular ingrowth material to the drainage plate or 5-fluorouracil treatment.…”

“…The rabbit has been considered as a useful model for evaluating histopathology or clinical outcome in glaucoma surgery. [20][21][22][23]27,28 In addition, it has been known that there are little difference in protein distribution between human and rabbit aqueous humor. 29 Therefore, we believe that our findings may apply to humans to a certain extent.…”

Induction and Mechanism of Apoptosis by Hydroxycamptothecin in Human Tenon's Capsule Fibroblasts

“…However, the reported failure rate is approximately 15% to 30%. [4][5][6] The main reason for surgical failure is the proliferation of fibroblasts leading to scarring of the channel in the filtration area. To control postoperative scarring, antiproliferative agents, such as mitomycin C or 5-fluorouracil, are used to prevent fibroblast growth and scar formation.…”