Transpupillary retinal photocoagulations were performed on ten eyes of five pigmented rabbits using a diode laser (Nidek Co., LTD, Aichi, Japan) emitting infrared radiation at 800 nm wavelength. A histological and an ultrastructural study on the treated eyes were done at 1, 3, 5, and 7 days after retinal photocoagulations. The purpose of this study was to observe the sequential changes in the retina and the choroid following transpupillary diode laser retinal photocoagulations at the parameters of laser power which produced a grayish white retinal discoloration with distinct white center. It seemed that the lesion was grade 3 retinal photocoagulation by Tso et al's classification. It appeared that the parameters necessary to produce grade 3 photocoagulation lesions were 160 mW power, and 0.2 second duration at 200 microns size. In general, with an agreement to other reports, histologic study of the diode laser lesions showed that the outer retina was damaged more severely than the inner retina. However, on day 1 after laser treatment, the alterations were more profound in the inner retina than in the outer retina and an occasional swelling of the axons in the nerve fiber layer was observed on the ultrastructural study. The results observed have not been found in other previous studies and suggest that the inner retina might be injured directly by 800 nm wavelength diode laser radiations. Thus we could conclude that 800 nm wavelength diode radiation might be absorbed by melanin pigment and also by other chromophores contained in inner retinal tissues. Further studies must follow to verify the laser-tissue interactions in diode laser retinal photocoagulations.
Animals ; Laser Coagulation/*adverse effects ; Rabbits ; Retina/pathology/*radiation effects/ultrastructure

Little is known about the natural history and management of choroidal neovascularization (CNV) which developed as a complication of laser photocoagulation for central serous chorioretinopathy (CSC). We experienced two patients with CNV which developed after laser treatment for CSC. Submacular membranectomy was performed on both cases after the confirmation of subretinal CNV with optical coherence tomography. One patient received photodynamic therapy for recurrent CNV. The vision of both patients has been improved over 6 months of follow up. These cases suggest that active intervention, including submacular surgery, improves the visual prognosis of this condition.
Adult ; Choroid Diseases/*surgery ; Choroidal Neovascularization/etiology/*surgery ; Diagnostic Techniques, Ophthalmological ; Female ; Human ; Interferometry ; Laser Coagulation/*adverse effects ; Light ; Male ; Retinal Diseases/*surgery ; Tomography ; Treatment Outcome ; Visual Acuity

Increasing number of endovenous techniques are available for the treatment of saphenous vein reflux and endovenous laser ablation (EVLA) is a frequently used method. A newly developed alternative, based on thermal therapy, is endovenous microwave ablation (EMA). This study evaluated the effect of the two procedures, in terms of coagulation and histological changes, in occluding lateral veins in goats. Twelve animals were randomized into two group, with 6 treated with EMA (EMA group), and the rest 6 with EVLA (EVLA group). Results of coagulation, including coagulation, fibrinolysis and platelet activation, were assessed at three or four different time points: before, immediately after, 24 h (and 48 h) after ablation. The diameter change, a measure of efficacy, was ultrasonographically measured before and 1 month after the ablation. Histological changes were grossly and microscopically evaluated immediately, 1 and 3 month(s) after the ablation. The length of the ablated vein and preoperative average diameter were comparable between the two groups. In both EMA and EVLA groups, several coagulation parameters, fibrinolysis and platelet activation parameters only underwent slight changes. Ultrasound imaging displayed that the diameter reduction of the veins treated by EMA was significantly larger than by EVLA, in consistent with the results of macroscopic examination. Microscopic examination revealed necrosis and thickening of the vein wall, and occlusion of the lumen within 3 months after ablation in both EMA and EVLA groups. It is concluded that EMA is a minimally invasive therapy, which appears to be safe and effective for treatment of lateral veins in goats.
Animals ; Female ; Fibrinolysis ; Fibrosis ; etiology ; Goats ; Laser Coagulation ; adverse effects ; instrumentation ; methods ; Male ; Microwaves ; therapeutic use ; Necrosis ; etiology ; Platelet Activation ; Postoperative Complications ; Venous Insufficiency ; etiology ; surgery

PURPOSE: This study was designed to evaluate the efficacy of fluid-gas exchange for the treatment of postvitrectomy retinal detachment. METHODS: We retrospectively reviewed the records of 33 consecutive patients (35 eyes) who underwent fluid-gas exchange treatment for postvitrectomy retinal detachment using the two-needle pars plana approach technique. RESULTS: The retinal reattachment rate was 80.0% after complete intravitreal gas disappearance following the fluid-gas exchange; the overall success rate was 65.7%. Visual acuity was improved or stable in 80.0% of cases; a two-line or greater vision improvement or a best-corrected visual acuity of 0.4 or better occurred in 62.9% of cases. The success rates for superior retinal detachments and posterior pole retinal detachments were 76.5% and 85.7%, respectively. CONCLUSIONS: Fluid-gas exchange represents a simple and cost-effective alternative outpatient procedure for retinal reattachment without reoperation for the treatment of superior and posterior pole retinal detachments.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Female ; Fluorocarbons/*administration & dosage ; Follow-Up Studies ; Humans ; Injections ; Laser Coagulation/methods ; Male ; Middle Aged ; Ophthalmoscopy ; Postoperative Care/*methods ; Retinal Detachment/diagnosis/etiology/*therapy ; Retrospective Studies ; Sulfur Hexafluoride/*administration & dosage ; Time Factors ; Treatment Outcome ; Visual Acuity ; Vitrectomy/*adverse effects ; Vitreous Body ; Young Adult