May 2004
Volume 45, Issue 13
Free
ARVO Annual Meeting Abstract  |   May 2004
Comparison Of PDT With Verteporfin And Intravitreal Triamcinolone Acetonide Injection In A Rat Model Of Laser–induced Choroidal Neovascularization
Author Affiliations & Notes
  • R. Li
    Preclinical Development,
    QLT Inc., Vancouver, BC, Canada
  • K. Nelkenbrecher
    Preclinical Services,
    QLT Inc., Vancouver, BC, Canada
  • M. McGrogan
    Preclinical Services,
    QLT Inc., Vancouver, BC, Canada
  • C. Lenihan
    Preclinical Services,
    QLT Inc., Vancouver, BC, Canada
  • S. Ip
    Preclinical Development,
    QLT Inc., Vancouver, BC, Canada
  • G. Lewis
    Preclinical Development,
    QLT Inc., Vancouver, BC, Canada
  • C. Smits
    Preclinical Services,
    QLT Inc., Vancouver, BC, Canada
  • P. McNicol
    Scientific Affairs,
    QLT Inc., Vancouver, BC, Canada
  • P. Margaron
    Preclinical Development,
    QLT Inc., Vancouver, BC, Canada
  • Footnotes
    Commercial Relationships  R. Li, QLT Inc. E; K. Nelkenbrecher, QLT Inc. E; M. McGrogan, QLT Inc. E; C. Lenihan, QLT Inc. E; S. Ip, QLT Inc. E; G. Lewis, QLT Inc. C; C. Smits, QLT Inc. E; P. McNicol, QLT Inc. E; P. Margaron, QLT Inc. E.
  • Footnotes
    Support  none
Investigative Ophthalmology & Visual Science May 2004, Vol.45, 472. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      R. Li, K. Nelkenbrecher, M. McGrogan, C. Lenihan, S. Ip, G. Lewis, C. Smits, P. McNicol, P. Margaron; Comparison Of PDT With Verteporfin And Intravitreal Triamcinolone Acetonide Injection In A Rat Model Of Laser–induced Choroidal Neovascularization . Invest. Ophthalmol. Vis. Sci. 2004;45(13):472.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Abstract: : Purpose: While verteporfin (Visudyne®, Novartis AG) photodynamic therapy (PDT) rapidly occludes choroidal neovascularization (CNV), it also induces a transient inflammation in the surrounding choriocapillaris. This inflammation may play a role in further angiogenesis and the reappearance of vascular leakage approximately 3 months after PDT. Intravitreal administration of triamcinolone acetonide (TA) was previously shown to impede the acute inflammatory response to PDT in a rabbit chorioretinal model. We have undertaken to evaluate the effects of PDT and TA on CNV in a rat model, and here we first report the impact of verteporfin PDT or intravitreal TA injection on CNV closure rates. Methods: CNV was induced using an 810 nm photocoagulation laser. Two to three weeks after photocoagulation, CNV was treated with PDT using intravenous bolus injection of 6 (n=18) or 12 mg/m2 (n=12) verteporfin plus 25 J/cm2 light at a fluence rate of 150 mW/cm2 10 to 25 min after verteporfin administration. Alternatively, 0.2 mg TA was intravitreally delivered into eyes with CNV lesions at a similar developmental stage (n=21). The rats were monitored for 28 days after treatment by fundus photography, fluorescein angiography, and immunostaining CNV tissues for CD31. Results: TA did not impact on the vascular leakage in established CNV during the 28–day follow–up after intravitreal injection. In contrast, all CNV lesions treated with verteporfin PDT were occluded at Day 1, regardless of the PDT regimen. CNV lesions exposed to PDT with 12 mg/m2 verteporfin remained closed over the course of the study, whereas for the 6 mg/m2 regimen, the closure rate dropped to 0–50% from Day 7 to Day 28. Conclusions: Verteporfin PDT was more rapid and effective in occluding CNV in rats than intravitreal TA injection. The effect of PDT on CNV closure depended on the dose of verteporfin and the timing of light delivery. The effects of the combination of PDT and intravitreal TA on CNV occlusion are being evaluated and may contribute to the scientific rationale for investigating the therapeutic benefits of combined PDT and TA treatments for the wet form of age–related macular degeneration in humans.

Keywords: choroid: neovascularization • photodynamic therapy • corticosteroids 
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×