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Patients with neovascularization of the iris were treated with cryocoagulation of the peripheral retina alone (Group A, n = 29), or in combination with cryocoagulation of the ciliary body (Group B, n = 19). The basic disease was either diabetic retinopathy or occlusion of the central retinal vein. After a follow-up of at least six months, a marked reduction in neovascularization of the iris was seen in most eyes. Intraocular pressure was reduced from a mean of 35.4 to 13.4 mm Hg in Group A, and from 55,2 to 6 mm Hg in Group B. A phthisis bulbi developed in six of 30 eyes (20%) in Group A and in 11 of 20 eyes (55%) in Group B.

Thirty-two eyes in 28 patients with anterior chamber angle neovascularization were prospectively treated with panretinal photocoagulation. Of 17 eyes that had less than 270 degrees angle closure, with an intraocular pressure of less than 40 mm Hg prior to treatment, 16 showed complete disappearance of the angle neovascularization and stabilization of the peripheral anterior synechiae after treatment. None of the 15 patients who had angle closure of 270 degrees or greater, or an intraocular pressure of above 40 mm Hg, showed any significant improvement after treatment. These results suggest that panretinal photocoagulation offers a highly effective means of dealing with early and moderately advanced cases of angle neovascularization.

The eye of a patient with age-related macular degeneration was treated with krypton laser photocoagulation and later studied histopathologically. Five months after treatment the original membrane was completely obliterated, but a separate new membrane was found, which was fed by the retinal circulation and not by the choroid. The frequency of such recurrences is not known, but they may be related to krypton laser treatment.

One day before enucleation for choroidal melanoma, four patients consented to experimental laser photocoagulation for the purpose of comparing the histopathologic appearance of acute chorioretinal lesions produced by various dye laser wavelengths with krypton red and argon green laser controls. Three patients had simulated "light" and "heavy" treatment of an extrafoveal choroidal neovascular membrane (CNVM) with wavelengths 577 nm (yellow), 595 nm (orange), and 600 nm (orange). One patient had simulated panretinal photocoagulation (PRP) with four different dye laser wavelengths. Extrafoveal "light" treatment with the three dye wavelengths and both controls spared the inner retina and produced similar effects in the outer retina, pigment epithelium, and choriocapillaris. Choroidal penetration was deepest with the longer wavelengths (590-647 nm) in both "light" and "heavy" treatment groups. "Heavy" treatment gave varying degrees of full-thickness retinal uptake for all dye and both control wavelengths. Both ends of the orange spectrum (590-600 nm) produced the most severe inner retinal uptake. Panretinal photocoagulation produced similar full-thickness retinal uptake for all four dye wavelengths tested. These results indicate that caution should be used when treating "heavily" with 590 and 600 nm in the extrafoveal area.

The cause of vitreous hemorrhage in aphakic eyes is sometimes difficult to ascertain, especially if fundus details are obscured. A vitreous hemorrhage secondary to corneoscleral wound neovascularization developed in nine eyes of eight patients 10 months to 17 years after intracapsular cataract surgery. Visualization of superior angle neovascularization, provocation of bleeding by rocking the gonioscopic contact lens, and documentation of vascular leakage by gonio-fluorescein angiography established the diagnosis. All affected eyes have remained hemorrhage-free after argon laser photocoagulation of the angle neovascularization. The clinician should be aware of cataract wound neovascularization, an apparently easy disorder to diagnose and treat, as a cause of vitreous hemorrhage.

Conventionally, unnecessarily intense laser power is advocated for the treatment of subretinal neovascular membranes. Among the four variables determining the adequacy of the laser lesion, namely spot size, duration of exposure, wavelength, and power, the latter is seldom if ever directly considered. Patients with subretinal neovascular membranes may be satisfactorily treated using the unfiltered argon blue-green laser wavelengths and reduced power as an additional option to the filtered argon green and wavelength or krypton yellow or red wavelengths.

We treated 12 eyes with advanced neovascular glaucoma with a modification of drainage implant surgery. All 12 eyes had rubeosis iridis and severe pain and nine had undergone previous glaucoma surgery. After follow-up periods of two to 24 months (mean, 11.3 months), nine of 12 eyes had intraocular pressures of less than 24 mm Hg (mean preoperative value, 49.5 +/- 8.2 mm Hg; mean postoperative value, 22.2 +/- 12.9 mm Hg). Surgery was unsuccessful in three eyes, in two because the anterior chamber remained flat postoperatively and in one because a large hyphema blocked the tube 15 months postoperatively. Our procedure, which uses a Y-shaped Teflon tube, is easy to perform, is well tolerated by the eye, and is associated with a low risk of serious complications.

A serous hemorrhagic maculopathy with a subretinal neovascular membrane appears in about 70% of cases of angioid streaks. In this study a series of 60 eyes (31 patients) was reviewed. In 13 eyes macular subretinal neovascularizations were photocoagulated with blue-green argon laser, green argon laser, dye laser (rhodamine 6G) at 590 nm and red krypton laser. The authors present and discuss the results obtained and suggest that photocoagulation of subretinal new vessels not involving the fovea can be worth performing.

Retinal neovascularization is one of many forms of new vessel formation in the eye. The chief cause is diabetic retinopathy and the severe retinal and vitreous complications can now be significantly reduced by argon laser and xenon arc coagulation. Although the natural history of proliferative retinopathy is well described, clinical details of monitoring the progress and regression have not been described. This paper describes the signs of active proliferation of arrest and regression both spontaneously and as a result of laser photocoagulation. Vitreous detachment is considered in some detail together with the factors which control the visual outcome after this significant event in the natural history of the retinopathy. The purpose of the paper is to provide a more rational approach to photocoagulation of retinal neovascularization.

Two patients with choroidal osteoma, one with bilateral involvement, diagnosed by fluorescein angiography, ultrasonography and CT scanning are presented. The clinical presentation, differential diagnosis and significance are discussed.

Fifty-one eyes with senile macular degeneration and a well-defined subretinal neovascular membrane located within 250 microns from the center of the foveal avascular zone were treated with krypton red laser photocoagulation. Follow-up ranged from 8 to 18 months (mean, 10 months). The eyes were divided into two groups based upon the location of the neovascular membrane. Group I (juxtafoveal membrane 1 to 250 microns from the center of the foveal avascular zone) contained 26 eyes. Following treatment the visual acuity in 16 of the 26 eyes (62%) improved by two or more lines on the Snellen chart or stabilized. Group II (subfoveal membrane present under the center of the foveal avascular zone) contained 25 eyes. Following treatment only 7 of 25 eyes (28%) improved by two or more Snellen lines or maintained their pretreatment visual acuity. Of 16 eyes that had a pretreatment visual acuity of 20/100 or better, only 2 eyes (12%) remained in this group following treatment.

The size of macular scotomata is determined numerically by a series of parallel F2 programs of the Octopus Perimeter. As long as useful foveolar fixation is maintained, the results are reproducible within the limits due to fluctuation of the retinal sensitivity. The scotomata can be mapped on a fundus photograph either by direct calculation or after perimetric determination of a reference distance, e.g., foveola-disc or between angioscotomata. This method furnishes useful information which can facilitate evaluation of different types of lasers in macular photocoagulation.

Since 1977, the author has treated proliferative diabetic retinopathy (PDR) under a protocol using DRS-style panretinal photocoagulation (PRP), with supplemental PRP, panretinal cryotherapy, and vitrectomy as needed. A total of 55 eyes (33 patients) were started on this protocol between 1/1/77 and 4/30/82. Follow-up averages 33 months (range: 12-80 months). Forty-nine eyes (89%) required PRP only; two eyes received panretinal cryotherapy, and four had vitrectomies. Visual acuity was maintained or improved in 44 eyes (80%); 48 eyes (87%) retained visual acuity of 20/100 or better. The major cause of visual loss was diabetic maculopathy.

Krypton laser treatment was performed in 30 eyes with subretinal neovascularization, in 27 eyes associated with senile exudative maculopathy. In 22 eyes treatment was initially successful but late recurrences occurred in 5 eyes; in only one of them was additional krypton treatment again successful. In 8 eyes the response to treatment was insufficient. The outcome in our series is promising but long-term results may be less favourable on account of more recurrences and progression of the underlying maculopathy.

Disc neovascularization developed in one eye of a 40-year-old white woman with the acute retinal necrosis syndrome. Krypton laser scatter photocoagulation was placed in areas of nonnecrotic and segmentally nonperfused retina that were demonstrated by fluorescein angiography. Marked reduction in disc neovascularization was noted clinically 16 days after laser treatment and was confirmed angiographically 4 weeks after treatment. Neovascularization was completely regressed at 9 weeks after treatment. The authors postulate that the retinal vasculitis and nonperfusion produced retinal ischemia which stimulated neovascular proliferation, and that photocoagulation caused regression of the neovascularization.

Over the past 20 years, fluorescein angiography has demonstrated its value in the diagnosis and management of most diseases of the retinal vessels and choroidal vessels, including diabetic retinopathy, aging macular degeneration, and venous occlusive disorders. Fluorescein angiography has become so important for diagnostic purposes and for laser management that it has become a standard technique in the authors' most carefully performed clinical research studies such as randomized clinical trials. These clinical trials demand fluorescein angiography not only for diagnosis and eligibility of patients, but also to document the adequacy of laser photocoagulation. The use of fluorescein angiography has encouraged the development of newer photographic techniques and has encouraged a commendable level of expertise among photographers. Experience with fluorescein angiography in clinical trials has led to the development of general guidelines for the use of angiography for the management of patients outside the confines of a clinical trial; we emphasize the importance of recent angiography as a general guideline for all patients with macular edema or choroidal neovascularization before consideration of laser photocoagulation.

This report analyses the results of cryotherapy in 22 eyes with severe retinopathy of prematurity (acute retrolental fibroplasia) and compares the results with data from other sources on untreated eyes. The evolution of the indications for and methods of treatment, the results of treatment, and related features are discussed. The need for a common terminology and classification of the disease is emphasized.

Panretinal photocoagulation (PRP) is widely used for a variety of ischemic ocular conditions. In diseases that produce neovascularization of the iris (NVI), such as diabetes mellitus and central retinal vein obstruction, a judiciously timed PRP can reduce the incidence of neovascular glaucoma. Neovascularization of the iris can occur after central retinal artery obstruction (CRAO) as well. In this article, the authors report the outcome of 17 patients who received PRP to treat rubeosis iridis secondary to CRAO. Eleven of the 17 patients (65%) showed regression of NVI after PRP. Although the uncontrolled and retrospective nature of this study precludes drawing definitive conclusions from these data, PRP appears to be effective in reducing the incidence of neovascular glaucoma, if it is delivered before the development of elevated intraocular pressure (IOP). Once neovascular glaucoma occurs, additional modalities appear to be necessary in order to adequately control the elevated IOP.

Increasing experience with the diagnosis of retinal pigment epithelial (RPE) tears has led to expanded recognition and understanding of this clinical entity. The authors report 18 RPE tears followed for an average of 28 months; 16 were associated with age-related macular degeneration and 2 with presumed ocular histoplasmosis syndrome. Retinal pigment epithelial dehiscences fell into four categories: nine spontaneous tears associated with choroidal neovascularization, one tear associated with an RPE detachment without choroidal neovascularization, four iatrogenic tears occurring at krypton treatment of choroidal neovascularization, and four iatrogenic tears developing weeks to months after laser treatment of choroidal neovascularization. Eight patients had a final visual acuity of 20/100 or better, four were 20/200, and six were 20/400 or worse. Photocoagulation, particularly with the use of krypton red laser, may be modified on the basis of possible RPE tear formation. Heightened awareness of the possibility of inducing pigment epithelial rips should improve diagnosis and management of these cases.

Sickle cell retinopathy in its advanced form is complicated by preretinal neovascularization, vitreous hemorrhage, and retinal detachment. Treatment of neovascularization can be performed with photocoagulation. Complications such as retinal breaks, retinal detachments, and choroidally fed neovascularization may result from such treatment. The risks vs. the benefits of various types of photocoagulation are currently being evaluated. Cryotherapy also may be used to treat neovascularization. It is currently being used in eyes with media that are too hazy to permit photocoagulation. It is used commonly during scleral buckling and vitrectomy procedures. In eyes with decreased visual acuity secondary to prolonged vitreous hemorrhage, pars plana vitrectomy can be utilized to produce optically clear media. Complications (including erythrocyte-induced glaucoma), however, may be severe. Retinal detachment can be treated by scleral buckling, but the markedly increased risk of anterior segment ischemia in patients with sickle cell hemoglobin necessitates preoperative, intraoperative, and postoperative prophylactic measures to minimize the risk of this potentially devastating complication. In eyes with retinal detachment with cloudy media and severe vitreous traction, combined scleral buckling and vitrectomy may be necessary. These eyes are extremely fragile, and a successful result is currently obtained in only about 50% of such cases. Hyphemas in patients with sickle cell hemoglobinopathies, whether traumatically or surgically induced, may have devastating effects on the eye. If elevated IOP results decreased vascular perfusion of the eye may cause irreversible damage to the retina and optic nerve. Most antiglaucoma medications, when used in the sickle cell patient, have a narrow margin of safety. Therefore, early surgical intervention for the treatment of sickle cell hyphemas is currently being evaluated.

Proliferative sickle retinopathy (PSR) is usually described as a peripheral neovascular tuft in a "sea fan" like configuration. While neovascularization of the disc (NVD) is a common finding in proliferative diabetic retinopathy (PDR), to our knowledge only one other case has been reported of NVD in an S-C patient in the absence of other contributing conditions. PSR has been shown to regress after treating hypoxic peripheral retina with peripheral circumferential retinal scatter photocoagulation (PCRSP). The following is a case report of an S-C patient with PSR and NVD/NVR which was originally treated elsewhere with scatter argon laser photocoagulation from the vascular arcades to just behind the equator. The peripheral "sea fan" and NVD did not regress. PCRSP to the zone of peripheral ischemia was then performed, and regression of the NVD and peripheral "sea fan" was achieved. This case illustrates the importance of concentrating laser treatment to the zones of retinal ischemia to achieve regression of associated neovascularization.

Thirty-seven eyes initially treated with argon blue-green, argon green, or krypton red laser photocoagulation demonstrated a recurrent subretinal neovascular membrane (SRNVM) at the edge of the treatment scar extending into the foveal avascular zone and were retreated with krypton red laser photocoagulation. The subretinal neovascular membrane was due to the presumed ocular histoplasmosis syndrome (POHS) in 10 eyes, aging macular choroidal degeneration (AMCD) in 22 eyes, and miscellaneous causes in five eyes. Anatomic success, defined as complete obliteration of the recurrent SRNVM, was achieved in 26 eyes (70%). When compared to pretreatment visual acuities, 23 of 37 eyes (62.2%) had stable or improved postoperative visual acuities during the follow-up period. Twenty-six eyes were retreated one time; nine eyes required two retreatments; and two eyes required three retreatments. Final visual results showed visual acuity greater than or equal to 20/40 in 7 eyes (18.9%); visual acuity greater than or equal to 20/80 in 16 eyes (43.8%); visual acuity greater than or equal to 20/100 in 19 eyes (51.4%); visual acuity greater than or equal to 20/200 in 27 eyes (73%); and visual acuity greater than or equal to 20/400 in 34 eyes (91.9%).

We treated 30 eyes (24 patients) with angioid streaks and neovascular membranes using light coagulation. Of 30 eyes, 16 showed either ameliorated or unchanged visual acuity. Twelve of the remaining 14 eyes retained a visual acuity of 20/200 or better. In 11 patients, the fellow untreated eye showed central macular degeneration with loss of central vision. The follow-up period ranged from two months to 16 years (mean, 3.4 years).

One hundred fifty-seven patients with subretinal neovascularization (SRN) were treated in a prospective, nonrandomized, consecutive study with the krypton red laser (KRL). The patients were analyzed with respect to age, etiology of the SRN, location of the SRN, and pre- and post-treatment visual acuity in patients with at least three months follow-up. Previous studies have not investigated KRL photocoagulation within the foveal avascular zone (FAZ). The results of this study compare favorably with other large series in which patients with SRN located outside the FAZ were treated with the argon blue-green laser (ABGL).

Clinical research utilizing the yellow, orange, and red wavelengths of the liquid organic dye laser has demonstrated that this laser may be successfully used for photocoagulation of certain ophthalmic defects. The advantage of the dye laser as a photocoagulation source is its capability to produce monochromatic wavelengths at relatively high output powers through a large range of the visible spectrum. Therefore, a target tissue can be coagulated with minimal transmittal of laser energy through the ocular media, by the selection of a wavelength that would be most highly absorbed by that tissue. The dye laser, as a system that permits transspectral photocoagulation, should prove valuable in the treatment of ocular disease.

Results from the Macular Photocoagulation Study Group have shown that argon laser photocoagulation is beneficial in reducing the risk of severe visual loss in eyes with extrafoveal choroidal neovascular membranes secondary to senile macular degeneration (Senile Macular Degeneration Study or SMDS), ocular histoplasmosis (Ocular Histoplasmosis Study or OHS), or idiopathic neovascularization (Idiopathic Neovascularization Study or INVS). However, argon laser treatment has not been entirely successful in permanently eradicating active neovascularization from those eyes. Recurrent neovascularization in the form of either neovascularization contiguous with the treatment scar or independent neovascular membranes have been observed in 70 (59%) of the 119 SMDS eyes originally assigned to treatment, 40 (30%) of the 132 OHS eyes, and 11 (33%) of the 33 INVS eyes. Recurrence was accompanied by an increased frequency of severe visual loss. Characteristics of the patient, original lesion, and treatment were examined for their ability to predict recurrence. Cigarette smoking was related to the rate of recurrence in the SMDS (P = .02) and the INVS (P = .09). Younger age and female gender were associated with an increased frequency of recurrence in the OHS. Predictions of which eyes will suffer recurrence, however, cannot be made accurately. Therefore, careful follow-up of all treated eyes is indicated, particularly within the first year after initial argon photocoagulation.

The Ocular Histoplasmosis Study-Krypton Laser is a multicenter controlled clinical trial designed to determine whether krypton red laser photocoagulation is of value in preventing visual acuity loss in eyes with ocular histoplasmosis that have either choroidal neovascularization 1 to 199 micron from the center of the foveal avascular zone (FAZ) or choroidal neovascularization 200 micron or further from the FAZ center with blood and pigment extending within 200 micron of the FAZ center. Patients were assigned to photocoagulation (n = 143) or to observation only (n = 145). Recruitment of patients with such lesions has been stopped because more untreated eyes than treated eyes had experienced severe visual acuity loss. At one year after randomization, 24.8% (31/125) of untreated eyes, in contrast with 6.6% (8/121) of treated eyes, had lost six or more lines of visual acuity; by three years after randomization, the corresponding values were 24.6% (15/61) and 4.6% (3/64). The superiority of treatment was evident at every point in time after six months. There were no subgroups in which there was convincing evidence that treatment was harmful. Follow-up of all patients continues to assess long-term results of treatment.

A prospective study of 78 patients, treated with krypton red laser (KRL) photocoagulation, who had senile macular degeneration (SMD) and subretinal neovascular membranes (SRNVM) located within 200u of the center of the foveal avascular zone (FAZ), was undertaken to determine if complete eradication of the SRNVM would minimize the resultant foveal scar size and retain the maximal useful functional vision as compared to untreated fellow eyes with a disciform scar. The typical patient profile with SMD and subfoveal SRNVM included: average age, 73.6 years; caucasian, 99%; females, 62%; lightly pigmented iris, 70%; hyperopic refractive error, 93%; and evidence of bilateral involvement with either predisciform or disciform lesions, 73%. In comparing eyes treated with KRL having 100% FAZ involvement with fellow untreated eyes having disciform scars, the latter had poorer average visual acuity (44% vs 100% less than or equal to 20/200), scars which were an average of five times larger (8.4 vs 38.6 sq mm) and scotomas which were an average of six times larger (15.7 vs 90 sq cm) as determined by new microcomputer technology. In all bilaterally affected cases, eyes with smaller scars and scotomas required less magnification from a low vision aid to read continuous standardized 1M print. Sixteen of 17 patients (94%) preferred the low vision aid for their treated eye. These preliminary results suggest that treatment of SRNVM within the FAZ using KRL may be successful in arresting the progressive macular hemorrhagic-exudative damage typical of untreated cases which culminate in loss of central visual function. Successful treatment, by preserving areas of paracentral fixation, can enhance the chances of visual rehabilitation using conventional low vision aids.