Using computerized vitreous fluorophotometry (VFP, Fluorotron(TM)), we examined the effect of cryotherapy on the blood retinal barrier (BRB) and the effect of subtenon injection of methylprednisolone acetate (Depomedrol(R)). In experiment 1, the right eyes of the 13 pigmented rabbits were treated with heavy cryotherapy after baseline VFP readings. The freezes were applied at 6 places in each quadrant around the equator are in two rows, a total of 24 places circumferentially. The left eyes were reserved as controls. In 6 rabbits (cryo with steroid group), Depomedrol(R) 10 mg of Depomedrol was injected into subtenon space after cryotherapy. The other 7 rabbits were treated with cryotherapy only (cryo only group). The VFP readings were taken 1, 3, 5, and 7 days, 2, 3, 5, and 7 weeks after cryotherapy. Cryotherapy increased the breakdown of BRB significantly. The peak VFP readings were obtained 5 days after cryotherapy in the cryo only group and 7 days after cryotherapy in the cryo with steroid group. In the cryo only group, the severity of the breakdown of BRB was higher than in the cryo with steroid group, and the increased VFP readings could not be normalized until 7 weeks after cryotherapy. In experiment 2, both eyes of the 8 pigmented rabbits were treated with medium cryotherapy after baseline VFP readings. The freezes were applied at 3 places in the superior temporal quadrant and at 3 places in the superior nasal quadrant, a total of 6 places. Depomedrol(R) 10 mg was injected into subtenon space after cryotherapy in the right eyes only. The VFP readings were taken 1, 3, 5, 7, 10, and 14 days after cryotherapy. In this experiment, cryotherapy did not increase the breakdown of BRB. But in the right eye, the severity of the breakdown of BRB was significantly lower than in the left eye 7 and 10 days after cryotherapy. These results suggest that Depomedrol(R) can decrease the severity of the breakdown of BRB after cryotherapy, and may be useful in the prevention of proliferative vitreoretinopathy (PVR).
Animals ; Anti-Inflammatory Agents/*pharmacology ; Blood-Retinal Barrier/*drug effects ; Capillary Permeability ; *Cryosurgery/adverse effects ; Fascia ; Fluorophotometry ; Injections ; Methylprednisolone/*analogs & derivatives/pharmacology ; Orbit ; Rabbits ; Retina/*drug effects/surgery ; Vitreoretinopathy, Proliferative/prevention & control

A 37-year-old female, who had received modified radical mastectomy for cancer of her right breast, presented with decreased visual acuity in the left eye after radiation therapy for the management of the metastasis to her right brain 14 months ago. After ocular examination, we diagnosed her as radiation retinopathy. At the time of the first visit, the corrected best visual acuity was 0.4 in the left eye, and fundus examination revealed cotton wool spots and cystoid macular edema (CME). The findings in the right eye were normal except for cotton wool spots in the superior major arch. Fluorescein angiography (FA) showed marked telangiectasia and microaneurysms in her left eye but tiny microaneurysms in her right eye. Subsequent optical coherent tomography (OCT) showed CME. We injected intravitreal triamcinolone acetonide (TA). Two weeks after treatment, the visual acuity was improved to 0.6 and the retinal thickness was decreased. Three months later, the visual acuity in the left eye was dropped to 0.3 due to the recurrence of CME, so we injected intravitreal TA again. Five months later, visual acuity was improved to 0.5 and OCT revealed the improvement of CME. The incidence of radiation retinopathy is higher in the side nearer to radiation, but careful radiation blocking is also required on the opposite side of irradiation site considering the possibility of radiation retinopathy and careful observation is required on both sides of the eyes when performing fundus examination.
Adult ; Brain Neoplasms/*radiotherapy/secondary ; Breast Neoplasms/pathology/radiotherapy/surgery ; Diagnosis, Differential ; Female ; Fluorescein Angiography ; Follow-Up Studies ; Fundus Oculi ; Glucocorticoids/administration & dosage ; Humans ; Radiation Injuries/diagnosis/drug therapy/*etiology ; Retina/pathology/*radiation effects ; Retinal Diseases/diagnosis/drug therapy/*etiology ; Tomography, Optical Coherence ; Triamcinolone Acetonide/administration & dosage