strontium-radioisotopes and Cicatrix

Beta radiation has a long history as a treatment modality in ophthalmology. It is a convenient and practical method of applying radiation and has the advantage of minimal tissue penetration. There has been a recent resurgence in the use of beta radiation in other areas in medicine, such as the prevention of restenosis after coronary artery stenting. Beta radiation has been shown in vitro and in vivo to inhibit proliferation of human Tenon's fibroblasts, which enter a period of growth arrest but do not die. Effects on the cell cycle controller p53 have been shown to be important in this process. In ophthalmology, beta radiation has been used widely for the treatment of pterygium and is under evaluation for treatment of age-related macular degeneration and for controlling wound healing after glaucoma drainage surgery. In this latter role, beta radiation may be particularly appropriate for use in developing countries to improve the results of trabeculectomy while potentially avoiding some of the side effects of other antimetabolites.

Topics: Aged; Beta Particles; Brachytherapy; Cicatrix; Glaucoma; Humans; Lens, Crystalline; Macular Degeneration; Middle Aged; Pterygium; Strontium Radioisotopes; Wound Healing

Three patients with a choroidal melanoma, treated with HDR (High Dose Rate) Strontium-90 brachytherapy, underwent an enucleation. Radiation effect was only visible at the irradiation zone with a brisk transition to normal tissue. Tumour was replaced by necrotic and scar tissue. The underlying sclera had a markedly reduced number of fibrocytes, but no structural alteration of the collagen stroma.

Topics: Aged; Brachytherapy; Cell Count; Choroid; Choroid Neoplasms; Cicatrix; Collagen; Eye Enucleation; Female; Fibroblasts; Follow-Up Studies; Humans; Male; Melanoma; Middle Aged; Necrosis; Neoplasm Invasiveness; Neoplasm Recurrence, Local; Radiopharmaceuticals; Radiotherapy Dosage; Sclera; Strontium Radioisotopes

The effects of different doses of beta radiation from a strontium-90 source on the proliferation of human Tenon's capsule fibroblasts were studied. The cultured fibroblasts were exposed to doses of 100, 250, 500, 750, 1000, 1500, and 3000 rads, and cell numbers were counted at days 3, 7, and 14. Treatment inhibited the proliferation of the fibroblasts. At seven days the cells exposed to 3000 rads showed a decrease relative to the starting cell numbers, and at 14 days the cells exposed to 1500 and 3000 rads showed a decrease in cell numbers. The doses of radiation which inhibited cell proliferation more than 50% (at day 7 and 14) and yet did not cause a decrease in the cell population were 500, 750, and 1000 rads. beta Radiation reduces the proliferation of human Tenon's capsule fibroblasts, and at higher doses this effect may be more pronounced one and two weeks after irradiation.

Topics: Beta Particles; Cell Division; Cells, Cultured; Child, Preschool; Cicatrix; Dose-Response Relationship, Radiation; Eye; Fibroblasts; Humans; Strontium Radioisotopes; Trabeculectomy

Topics: Adult; Brachytherapy; Cicatrix; Female; Humans; Keloid; Male; Strontium Radioisotopes

Topics: Adolescent; Adult; Brachytherapy; Child; Child, Preschool; Cicatrix; Eustachian Tube; Female; Humans; Infant; Male; Otitis Media; Strontium Radioisotopes

Topics: Adult; Aged; Cicatrix; Ear Diseases; Eustachian Tube; Female; Follow-Up Studies; Humans; Male; Middle Aged; Pressure; Radiation Effects; Strontium Radioisotopes