Rabbit model of ocular indirect photodynamic therapy using a retinoblastoma xenograft
Autor: | Grecia Rico, Patricia Chévez-Barrios, Emily Zolfaghari, Bradley H. Jacobsen, Charles J. Gomer, Diana K. Lee, Lei chi Wang, Kevin Stachelek, Ingy Madi, Jesse L. Berry, Narsing A. Rao, Jonathan W. Kim, Angela Ferrario |
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Rok vydání: | 2017 |
Předmět: |
medicine.medical_specialty
Porphyrins genetic structures Retinal Neoplasms medicine.medical_treatment Scars Photodynamic therapy Intraocular Retinoblastoma Ophthalmoscopy 03 medical and health sciences Cellular and Molecular Neuroscience 0302 clinical medicine Ophthalmology medicine Animals Retina Photosensitizing Agents medicine.diagnostic_test Retinoblastoma business.industry Verteporfin Neoplasms Experimental medicine.disease Xenograft Model Antitumor Assays eye diseases Sensory Systems Surgery Treatment Outcome medicine.anatomical_structure Photochemotherapy 030220 oncology & carcinogenesis Injections Intravenous 030221 ophthalmology & optometry Feasibility Studies Histopathology Rabbits medicine.symptom business medicine.drug |
Zdroj: | Graefe's Archive for Clinical and Experimental Ophthalmology. 255:2363-2373 |
ISSN: | 1435-702X 0721-832X |
DOI: | 10.1007/s00417-017-3805-8 |
Popis: | The goal of this project was to demonstrate the feasibility of coupling the indirect ophthalmoscope laser delivery system with the 690 nm wavelength diode laser used to perform photodynamic therapy (PDT) in the treatment of retinoblastoma. For phase 1, a total of six pigmented rabbits were treated with the indirect laser delivery system. The laser source was provided by the Lumenis Opal 690 nm laser unit, delivered through a 810 nm Indirect ophthalmoscope headpiece and a hand-held 28-diopter indirect lens (1.0 mm spot size). Four rabbits received intravenous verteporfin at doses of 0.43 or 0.86 mg/kg, and two rabbits did not receive verteporfin (controls). A second phase of the study involved eight rabbits using a retinoblastoma xenograft to determine the effect of indirect PDT on subretinal tumors. For phase 1, a total of 20 laser treatments were performed in the right eyes of six rabbits. Laser power levels ranged between 40 and 150 mW/cm2 and treatment duration ranged between 1 and 3 min. In the four rabbits that received verteporfin, focal retinal scars were noted at 40 mW/cm2 and higher power levels. In the two control rabbits that did not receive verteporfin, thermal burns were confirmed at 75 mW/cm2 and higher power levels. Histopathology showed focal retino-choroidal scars at the site of PDT treatment, without evidence of generalized ocular damage. Using the retinoblastoma xenograft, the indirect PDT system was shown to cause areas of tumor necrosis on histopathology. The results of this pre-clinical study suggest verteporfin may be activated in the rabbit retina with the indirect delivery system and the 690 nm laser unit (i.e., Indirect PDT). Using verteporfin, treatment effects were observed at 40–50 mW/cm2 in the rabbit retina, while photocoagulation was achieved at 75 mW/cm2 and higher power levels. Fundoscopic and histopathologic examination of treated areas showed circumscribed areas of retinal damage and a lack of generalized ocular toxicity, suggesting that this modality may represent a safe and localized method for treating intraocular retinoblastoma. |
Databáze: | OpenAIRE |
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