[Eye fundus autofluorescence technique in the early diagnosis of age-related macular degeneration].

Autofluorescence (AF) of the eye fundus is one of the most promising studies. AF provides specific molecular information on the retinal pigment epithelium and enables one to diagnose early phenotypic changes that are predictors for progression of age-related macular degeneration. Many investigations have demonstrated that AF is a valuable clinical technique that should be improved in order to have information accessible to a patient on the diagnosis and prediction of age-related macular degeneration.

Chronic radiation-induced alteration in hematopoietic repair during preclinical phases of aplastic anemia and myeloproliferative disease: assessing unscheduled DNA synthesis responses.

Protracted, low-daily-dose gamma-ray exposure (3.8-7.5 cGy/day) segregates canines into separate survival- and pathology-based subgroups by the early elicitation of distinct, repair-mediated hemopathological response pathways. In this study, we verified the blood and marrow responses of two major subgroups prone to either aplastic anemia or myeloproliferative disease, along with two variants, and extended our analyses of hematopoietic repair to include studies of DNA repair in bone marrow blasts using an autoradiographically based unscheduled DNA synthesis (UDS) assay. The myeloproliferative disease-prone subgroup exhibited extended survival (> 200 days), related to partial, gradual restoration of blood leukocyte, platelet, and marrow progenitor levels following an initial phase of acute suppression. Marrow blasts taken during the restoration phase showed expanded and qualitatively modified UDS relative to marrow blasts of age-matched control animals. The amount of UDS per blast (signal strength) increased significantly, as did the number of UDS-positive cells and their sensitivities to high-dose UV induction and 1-beta-D-arabinofuranosylcytosine chemical inhibition. A nonevolving myeloproliferative disease-prone variant having prolonged survival (> 200 days) and restored blood cells and marrow progenitor levels also had marrow blasts with expanded UDS responses, but these were uniquely evoked by low (but not high) doses of UV inducer. The aplastic anemia-prone subgroup was characterized by short survival (< 200 days), progressive decline (without restoration) in all measured blood and marrow compartments, and largely nonsignificant changes in UDS responses of marrow blasts. A variant of this aplastic anemia-prone subgroup (with comparable short survival due to markedly ineffective hematopoiesis, but expressing select preleukemic features) exhibited reduced numbers (relative to age-matched controls) of highly responsive, UDS-positive marrow blasts (in terms of UDS signal strength and increased to sensitivity 1-beta-D-arabinofuranosylcytosine-induced UDS inhibition). From these observations we conclude that: (a) the UDS response of marrow blasts, a correlate of hematopoietic progenitorial repair, is altered differentially within selected subgroups of animals under chronic radiation exposure; and (b) the nature of altered UDS repair response patterns appears to be largely related to the preclinical status/predisposition of the individual animal and thus may provide prognostically useful information in the clinical monitoring of chronically irradiated individuals with minimal but evolving hematological disease.

Pathologic mechanisms of multifocal choroiditis with retinal detachment after carotid injection of Streptococcus mutans and other bacteria in dogs.

Multifocal choroiditis with overlying retinal detachment occurs after carotid injection of certain bacteria in dogs. The ocular lesions occur mainly in the tapetal area of the retina, correlate with microabscesses in the inner choroid and subretinal space, and occasionally occur in the inner retina and anterior uveal tract. The major pathophysiologic factor involved in the dog model of septic choroiditis appears to be embolization of the choriocapillairies by "live" bacteria, which clump and adhere well to tissues. In the dosages used, antibiotics did not prevent or alter the severity of the fundus lesions.

Septic choroiditis with serous detachment of the retina in dogs.

The present study describes a model of multifocal septic choroiditis with serous retinal detachment after intracarotid injection of Staphylococcus aureus or Streptococcus faecalis. The fundus lesions occurred mainly in the tapetal area and, on ophthalmoscopic examination, were more extensive after S. aureus than after S. faecalis injection. On histopathologic examination there were microabscesses in the inner choroid and subretinal space, disrupting the outer retina but sparing the inner retina.

Monozygotic twins with age-related macular degeneration.

This clinical study, to the best of our knowledge, is the first report of severe age-related macular degeneration in both identical twins, documented as monozygotic by genetic testing. This suggests that genetic factors may be of primary importance in certain cases of age-related macular degeneration.

Ultrasonography of vitreal foreign bodies in eyes obtained at autopsy.

A- and B-scan ultrasonography was done on phakic human eyes obtained at autopsy. Various foreign bodies had been placed separately in the vitreous. The results suggest that both object shape and composition are of major importance in determining specific ultrasonographic patterns.

Simultaneous external subretinal fluid drainage and intravitreal gas injection.

Simultaneous external subretinal fluid drainage and intravitreal gas injection was performed in 12 patients requiring a large or near-total internal gas tamponade (eight eyes with proliferative vitreo-retinopathy following vitrectomy and four eyes without proliferative vitreoretinopathy that had not undergone vitrectomy). None of the patients had a preexisting or intentional posterior retinal break. The retina was attached six or more months postoperatively in nine of the 12 patients. In one patient, an iatrogenic retinal break occurred without retinal incarceration. In selected cases, this procedure is an alternative to internal fluid-gas exchange through a posterior retinal break, thus avoiding the necessary postoperative facedown position, which is difficult for some patients to maintain. This method may also be used for preventing "fish-mouthed" retinal breaks in selected cases.

Treatment of retinal detachments with multiple breaks by pneumatic retinopexy.

Pneumatic retinopexy is a recent innovation in the treatment of uncomplicated retinal detachments due to a superior retinal break extending for 30 degrees or less. We describe four patients with retinal detachments involving multiple breaks who were successfully treated by a modification of this technique. One case involved a calculation of the size of the gas bubble required to achieve tamponade of both breaks simultaneously. The gas was then administered in two sequential injections, as the volume was too large to be given in a single dose. In the remaining three cases, the gas bubble was rotated from the position of tamponade for one break into a position where tamponade of the second break or groups of breaks was achieved.

Simultaneous external subretinal fluid drainage and intravitreal gas injection in nonvitrectomized eyes with a special 27-gauge needle.

In 12 patients with retinal detachment requiring a scleral buckle, simultaneous external subretinal fluid drainage, and intravitreal gas injection were performed to prevent "fishmouthed" retinal breaks in six patients and to achieve more complete drainage of subretinal fluid in six others with chronic inferior detachments. To simplify this technique in all of these nonvitrectomized eyes, we used a special 27-gauge needle sutured to the sclera.

Subretinal neovascularization associated with fundus flavimaculatus.

Hemorrhagic disciform degeneration centered in the fovea with serous detachment of the overlying neuroepithelium developed in two patients with fundus flavimaculatus. Fluorescein angiography disclosed the presence of subretinal neovascular membranes. There was no evidence of other diseases associated with subretinal neovascularization. Fundus flavimaculatus must be added to the growing list of diseases associated with subretinal neovascularization.

Combined illumination-irrigation 20-gauge probes for vitrectomy.

Combined illumination-irrigation 20-gauge probes that couple to the fiber-optic source on a vitrectomy machine (Ocutome) have performed well during surgery in selected cases.

Temporary loss of foveal contrast sensitivity associated with panretinal photocoagulation.

Snellen visual acuity and spatial contrast sensitivity measurements were used to monitor changes in foveal vision in two patients undergoing argon laser panretinal photocoagulation (PRP) in both eyes for proliferative diabetic retinopathy. Foveal edema developed in one of the four eyes. The remaining three eyes showed no signs of foveal edema, but developed temporary losses in high spatial frequency contrast sensitivity during the closely spaced PRP treatments. Since Snellen visual acuity remained stable at the prelaser level, these results indicate the need for more sensitive measures of visual resolution to monitor foveal integrity in patients undergoing PRP.

Abnormal chloroidal circulation: association with arteriovenous fistula in the cavernous sinus area.

Abnormalities in the choroidal circulation developed in two patients with arteriovenous fistulae in the area of the cavernous sinus. Fluorescein angiography in both patients revealed delayed filling of their choroidal circulation. In the first patient, this was associated with a central serous detachment of the retina secondary to a retinal pigment epithelial defect. In the second patient, a large choroidal detachment and serous retinal detachment, which resolved spontaneously developed. High venous pressure, low mean arterial pressure, and subsequent tissue hypoxia are postulated to be the cause of the altered choroidal circulation. The possibility of occult dural arteriovenous fistulae should be considered in the differential diagnosis in patients with a choroidal detachment, proptosis, and a red eye.

Macular edema after scatter laser photocoagulation for proliferative diabetic retinopathy.

Fluorescein angiography showed perifoveal capillary leakage in three cases of macular edema after scatter laser photocoagulation for proliferative diabetic retinopathy. The scatter laser photocoagulation in these cases may have been an important factor inthe pathogenesis of macular edema.

The incidence of fundus lesions in septicemia.

Ophthalmoscopic examination in a series of septicemic patients with positive blood cultures revealed a significant number of patients with fundus lesions. Review of the medical diagnoses and laboratory data did not show any consistent abnormalities differentiating between septic patients with or without fundus lesions. Septicemia should be considered in the differential diagnosis of cotton wool lesions, hemorrhages, or white-centered hemorrhages in the retina.

Repeated fluid-gas exchange for hypotony after vitreoretinal surgery for proliferative vitreoretinopathy.

Three patients with prolonged hypotony after vitreoretinal surgery for proliferative vitreoretinopathy were treated with repeated fluid-gas exchanges to maintain intraocular pressure and prevent the development of phthisis bulbi. We performed fluid-gas exchanges solely to treat the hypotony beyond the period when tamponade of retinal breaks was required, and without specific positioning of the bubble. In these patients, the intraocular pressure eventually returned to normal and useful vision was retained.

Retinal irradiance from vitrectomy endoilluminators.

We compared the maximum light output of selected 19- and 20-gauge continuous-fiber and detachable-tip endoilluminators to the retinal damage threshold for intravitreal fiber-optic light in the owl monkey. Because of cumulative light toxicity to the retina there is a substantial risk of retinal damage from endoillumination when the endoilluminator is close to the retina (for example, during membrane peeling procedures) and especially when the continuous-fiber endoilluminator with high light output is used.

Lens-induced glaucoma 65 years after congenital cataract surgery.

PURPOSE/METHODS: We observed an unusual case of lens-induced glaucoma that occurred 65 years after congenital cataract extraction. We successfully treated the patient by removing the residual lens material with pars plana vitrectomy. RESULTS/CONCLUSIONS: The intraocular specimen exhibited lens material, epithelial cells, and macrophages. It may have taken years for the residual lens material to denature and break into small pieces, which resulted in phacolytic and lens-particle glaucoma.

A twin study of age-related macular degeneration.

PURPOSE: To determine the importance of genetic factors in age-related macular degeneration by using a twin study to compare the concordance of age-related macular degeneration in monozygotic and dizygotic twin pairs. METHODS: We prospectively examined 134 consecutive twin pairs and two triplet sets for age-related macular degeneration. The zygosity was determined by genetic laboratory tests. RESULTS: The concordance of age-related macular degeneration was 100% (25 of 25) in monozygotic and 42% (five of 12) in dizygotic twin pairs. The other twins or triplets had no macular changes of age-related macular degeneration. CONCLUSIONS: The statistically significant higher concordance of age-related macular degeneration in monozygotic than in dizygotic twin pairs and the clinical heterogeneity of age-related macular degeneration strongly suggest the importance of genetic and nongenetic factors, respectively, in age-related macular degeneration.

Threshold for retinal damage associated with the use of high-power neodymium-YAG lasers in the vitreous.

Ultrashort, Q-switched or mode-locked, neodymium-YAG laser pulses focused within 2 mm of the retina caused reproducible retinal damage in four eyes of two monkeys and in four eyes of three rabbits. The distance of the laser focus from the retina for clinically observed threshold retinal damage was characterized for pulse energies up to 9 mJ. For the 2- to 6-mJ pulse energies necessary to rupture vitreal membranes in clear media in rabbits, the high-power laser pulses could not be focused within 2 mm of the retina without substantial risk of damaging the underlying retina. These laser pulses did not rupture vitreal membranes in hazy ocular media that prevented precise focusing. The retinal damage was somewhat greater than expected for retinal absorption of 1.06-micron laser energy, suggesting that secondary effects such as self-focusing and shock waves emanating from the focus may be important.