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Corneal argon laser photocoagulation (CALP) was used in 13 patients to treat deep stromal vascular ingrowth. Eight patients had undergone successful penetrating keratoplasty but had developed deep stromal vessels into the graft associated with signs of graft rejection, which did not improve with steroid treatment alone (group 1). After CALP, there was marked regression of the neovascularization with reversal of graft rejection in all eyes. Three additional patients with vascularized corneas, referred for penetrating keratoplasty, underwent CALP preoperatively with obliteration of the vessels (group 2). Two of these patients have since undergone keratoplasty and, in both, the grafts have remained avascular and clear over a 21-month follow-up. Two other patients with corneal injury and progressive corneal opacification and vascularization have also been treated with CALP (group 3). CALP may be a useful adjunct in the treatment of corneal neovascularization. Further clinical studies are needed to define its exact role.

Three hundred seventy eyes with advanced, active, proliferative diabetic retinopathy (PDR) and visual acuity of 10/200 or better were randomly assigned to either early vitrectomy or conventional management. After 4 years of follow-up, the percentage of eyes with a visual acuity of 10/20 or better was 44% in the early vitrectomy group and 28% in the conventional management group. The proportion with very poor visual outcome was similar in the two groups. The advantage of early vitrectomy tended to increase with increasing severity of new vessels. In the group with the least severe new vessels, no advantage of early vitrectomy was apparent.

This study was undertaken to determine whether the treatment benefit reported in randomized trials for patients with extrafoveal choroidal neovascular membranes (NVMs) secondary to age-related macular degeneration (AMD) or the ocular histoplasmosis syndrome (OHS) can be duplicated in other clinical settings. The visual results and recurrence rates in treated extrafoveal NVMs of 70 patients with AMD and 21 patients with OHS were similar to those reported by the Macular Photocoagulation Study Group, in which all treated patients received argon blue-green laser photocoagulation after the administration of retrobulbar anesthesia. In this study, 78% (71/90) of the patients were treated with krypton laser and only 35% (32/90) had retrobulbar anesthesia. These results suggest, but do not prove, that the wavelength of the laser used or the administration of retrobulbar anesthesia may not be critical variables in determining the success of treatment in patients with extra-foveal NVMs.

Twenty-six patients with idiopathic sub-retinal neovascular membranes (INVMs) located within the posterior pole were examined. Clinical and fluorescein angiographic features of these patients are described. Follow-up ranged from 2 to 96 months (mean 16.5 months). Laser treatment was performed according to the location of the neovascular membrane: 7 out of 9 eyes (77%) increased their final visual acuity or stabilized after Argon blue-green laser photocoagulation (INVMs further than 200 microns from the center of the fovea). Krypton red light laser treatment was performed in 13 eyes with juxta-foveal and sub-foveal INVMs: following treatment 10 eyes (77%) improved by 2 or more Snellen lines or maintained their pre-treatment visual acuity. Because of the fact that the Krypton laser was not yet available, 5 patients were not treated: all of them had sub-foveal (3) or juxta-foveal INVMs (2). The natural history of 4 cases (80%) showed an increase in the final visual acuity in 3 eyes and a steady state in one eye. Pathogenesis and treatment outcome of the disease are finally discussed.

The tuneable dye laser was used to simulate treatment of choroidal neovascularization and panretinal photocoagulation (PRP) in monkey retina. The histopathologic effects of wavelengths from 560 to 630 nm in juxtafoveal, papillomacular bundle, and nonfoveal areas were investigated. An unexpected observation using high-intensity burns in juxtafoveal and, to a lesser extent, in papillomacular bundle areas was inner retinal damage with 600-nm light. At moderate energy levels, the effect of 600 nm were more comparable with those with other wavelengths and included much less damage to the inner retinal layers. At mild energy levels, the effects were comparable with other wavelengths. During and after the application of the burns, the energy levels and ophthalmoscopic appearances were comparable for each wavelength for the high-, moderate-, and mild-intensity burns. The histopathologic effects of 630-nm light (tuneable dye red) were comparable with those of the standard krypton red (647 nm) laser. Nonmacular and PRP effects were similar with all wavelengths. These results indicate that power levels may need to be reduced when placing 600-nm (orange) laser burns in the macula.

Choroidal neovascularization in fellow eyes of patients with advanced disciform macular scars usually has an unfavorable prognosis. Fifty-two such fellow eyes were treated, using the monochromatic green argon laser. The neovascular membranes were foveal in 24 eyes, juxtafoveal in ten eyes, and perifoveal in 18 eyes. Complete closure of the choroidal new vessels after treatment was seen in 46 eyes. Only one eye in the foveal group and five eyes in the juxtafoveal group had residual new vessels. After an average follow-up period of 16 months, improvement or stabilization of vision was seen in 36 eyes--18 eyes in the foveal group, four in the juxtafoveal group, and 14 in the perifoveal group. In view of the rewarding anatomical and functional results, photocoagulation, using the monochromatic green argon laser, should be considered in these high-risk eyes. Treatment of foveal neovascular membranes seems to be indicated if the visual acuity is 20/70 or worse.

A 32-year-old man with atypical retinitis pigmentosa developed bilateral neovascularization of the optic disk. One year after the diagnosis, vitreous hemorrhage occurred in one eye. Panretinal photocoagulation of this eye resulted in some regression of the neovascularization.

New vessels in senile macular degeneration threaten central vision. To evaluate the effects of treatment a randomized prospective trial was undertaken between 1977 and 1981. This trial concerned destruction of subretinal new vessels by argon laser photocoagulation. The indications of photocoagulation depended on the location of new vessels in relation to the center of the fovea. New vessels amenable to this treatment were those that were clearly visible on angiography and located farther than 100 microns from the foveola. 60 patients were divided into 3 groups according to the distance of the new vessels from the fovea: 100-200 microns away; 200-400 microns away; and greater than 400 microns away from the center of the fovea. In each group patients were randomly assigned to treatment or no treatment. After at least one year follow-up, argon laser showed a statistically significant effect (p less of 0,01; Kolmogorow-Smirnov test) on the stabilization or the amelioration of visual acuity compared with the non treated group. There was no statistical difference in the 3 groups of new vessel location. In cases of failure, no differences in final visual acuity existed between the treated and the non-treated group.

The efficacy of argon blue-green laser treatment for extrafoveal choroidal neovascularization (CNV) in aging macular degeneration, presumed ocular histoplasmosis syndrome and idiopathic choroidal neovascularization has recently been proven by the Macular Photocoagulation Study. These results are applicable only to eyes managed according to certain principles of therapy and post-treatment follow-up. These include the use of a recent fluorescein angiogram and retrobulbar anesthetic, aiming for complete obliteration of the CNV. Meticulous post-treatment follow-up is critical. This includes daily patient monitoring of the Amsler grid, and prompt examinations if distortion is noted. Excellent quality fluorescein angiography is mandatory. This is repeated frequently and studied promptly. Residual or recurrent extrafoveal CNV requires prompt re-treatment.

Laser treatment of a subretinal neovascular membrane associated with a unilateral choroidal osteoma in a 28-year-old woman is described. To our knowledge, this is the first reported use of krypton red laser photocoagulation for the initial treatment of a subfoveal neovascular membrane in this setting. Early recognition of the membrane allowed treatment prior to involvement of the central fovea. Follow-up has shown obliteration of the membrane without recurrence and 20/20 vision. We emphasize recognition of this unusual tumor, self-monitoring with an Amsler grid, and early treatment of subretinal neovascularization in this high risk group of young patients.

A large variety of diseases may cause a subretinal neovascularization originating from choroidal vessels. Four cases of parapillary choroidal neovascularisation are described, including neovascularization caused by senile and myopic degeneration, by drusen of the optic nerve head, and by angioid streaks. Obliteration of the neovascular membrane with confluent argon laser coagulation reduced metamorphopsia and prevented a progredient loss of visual acuity in all four patients.

We studied 124 consecutive eyes that had laser photocoagulation for choroidal new vessel membranes (NVM) associated with pigment epithelial detachment (PED). In many cases, the extent of the NVM was uncertain. We thought it was not subfoveal in all cases but it possibly may have been subfoveal in one subgroup of cases. With a mean follow-up of 16 months, vision was stable or improved in 53% of the treated eyes. There was no difference in outcome between argon-treated and krypton-treated eyes. On the basis of fluorescein angiograms, we classified 86 of the eyes into four nonexclusive groups. Vision was stable or improved in 68% of eyes with juxtafoveal or extrafoveal PED, 48% with subfoveal PED, 76% with juxtafoveal or extrafoveal NVM, and 50% of eyes with possibly subfoveal NVM. A randomized clinical trial of laser photocoagulation for NVM in PED is both indicated and warranted. A pilot study under the auspices of the Macular Photocoagulation Study is now under way to determine the feasibility of and develop a protocol for such a trial.

The course of the vitreoretinal relationship in 272 eyes with diabetic retinopathy was studied retrospectively in an attempt to identify the prognostic role of the vitreous. In eyes with initial nonproliferative diabetic retinopathy, the development of neovascularization had a positive correlation with eventual partial posterior vitreous detachment (PVD) and a negative correlation with complete PVD. In eyes with initial proliferative diabetic retinopathy, those with active vitreous changes had a poor prognosis and those with inactive vitreous changes, an apparently good prognosis. Photocoagulation for retinal neovascularization was successful in most eyes with stable no-PVD but less successful in eyes that progressed to partial PVD. Therefore, considering the diabetic vitreous changes from a prognostic standpoint, the data suggest that if early proliferative changes are observed, photocoagulation before partial PVD develops might be considered.

A retrospective study was performed on 75 eyes with presumed ocular histoplasmosis syndrome and 59 eyes with aging macular degeneration to determine risk factors for visual loss in the early postoperative period after successful laser photocoagulation of primary and recurrent choroidal neovascular membranes (CNVMs). Despite successful obliteration of neovascularization, visual loss of two lines or greater occurred in 18.8% of eyes with presumed ocular histoplasmosis syndrome and 40.4% of eyes with aging macular degeneration (mean follow-up, 33.6 weeks). Factors which predicted visual loss after treatment included a short distance of CNVMs from the foveal center (P = 0.002), good preoperative visual acuity (P = 0.003), increased area of CNVM (P = 0.025), and postoperative internal limiting membrane wrinkling (P = 0.017). Eyes with CNVMs greater than 0.8 mm2 in area or less than 0.6 mm from the foveal center had at least twice the frequencies of visual loss of eyes without these characteristics.

Xenon arc and argon laser photocoagulation are equally effective in producing regression of disc neovascularization and maintaining visual acuity. Xenon has more destructive effects on the visual field and electroretinogram, but is more comfortable because retrobulbar anaesthesia is used and more convenient to the patient because fewer treatment sessions are needed.

A group of 20 patients (28 eyes) with proliferative retinopathy who required extensive argon laser photocoagulation to induce regression of new vessels is presented. The mean number of burns applied to each eye was 7225, with a maximum of 11,513. These were delivered in a mean of nine sessions over a mean period of 22.9 months. Twenty-five eyes (89%) had a final visual acuity of 6/18 or better. The remaining three eyes (11%) had severely reduced vision attributable to complications of proliferative diabetic retinopathy (traction retinal detachment involving the macula in two eyes and ischaemic maculopathy and a persistent vitreous haemorrhage in the third). Large amounts of confluent argon laser photocoagulation may be necessary for the elimination of new vessels in some patients, and it is our view that laser photocoagulation should be continued until regression of new vessels occurs. This is compatible with the retention of functional vision and good visual acuity.

In two patients, a detachment of the macula occurred following a branch retinal vein occlusion. Vitreoretinal relationships were investigated and documented by biomicroscopic photography. Both eyes showed partial posterior vitreous detachment with dense adhesions to a preretinal membrane at the macula. Vitreous contraction and traction appeared to be responsible for the detachment.

Argon laser photocoagulation can reduce the risk of severe vision loss in patients with age-related macular degeneration, ocular histoplasmosis, and idiopathic neovascularization. Early detection of neovascularization soon after the onset increases the likelihood of identifying patients with a new vessel membrane in a potentially treatable position. Patients with one or both eyes at risk for the development of a new vessel membrane should assess their central visual fields on a daily basis by occluding first one eye and then the other. Any disturbance in distance vision or reading vision or the appearance of distortion in the patient's field or on the Amsler grid should prompt an eye examination at the earliest feasible time, in an effort to detect neovascularization in a treatable position.

Presumed ocular histoplasmosis syndrome (POHS) is a commonly observed fungal infection. Ocular findings include peripapillary atrophy, peripheral punched-out lesions, and a macular subretinal neovascular membrane. Laser photocoagulation can be beneficial in reducing visual loss from macular scarring due to subretinal neovascular membranes. Herein we describe a patient with POHS in which laser treatment regressed a parafoveal subretinal neovascular membrane. Her vision improved from 20/70 to 20/20 in the treated eye.

A 19-year-old white woman with osteoma of the choroid developed a subretinal neovascular membrane with hemorrhage. This was treated with Argon laser photocoagulation and she has shown no evidence of recurrence 13 months after treatment.

Of 27 eyes with peripapillary choroidal neovascular membranes (PPCNM), 17 (63%) had age-related macular degeneration and ten (37%) were idiopathic. PPCNM were treated in 25 eyes using the monochromatic green argon laser. Two eyes were untreatable. After an average follow-up of 37.7 months, successful closure of the choroidal new vessels was obtained in 23 eyes (92%), and visual acuity was stabilized or improved in 20 (80%). Seven eyes (28%) had recurrences; in four, the new vessels extended into the macula. Post-treatment, three eyes ultimately had dry macular scars, and one had an exudative macular scar. Of these four eyes, only the one with a dry macular scar showed visual improvement. No treated cases showed arcuate scotoma.

We studied the ultrastructural characteristics of 23 vascularized preretinal membranes removed from 22 eyes during pars plana vitrectomy for proliferative diabetic retinopathy. Traction detachment of the macula was the most frequent reason for surgery (15 of 22 eyes), followed by nonclearing vitreous hemorrhage (seven of 22 eyes). Vessels found in the membranes were studied by serial sectioning and categorized as having either developing, mature, or regressing characteristics. Developing vessels were seen in ten of 23 membranes (43%), mature vessels in 19 of 23 membranes (83%), and regressing vessels in 13 of 23 membranes (57%). Endothelial fenestrations and cell separations were rare. With three-dimensional reconstruction, we found that new vessels often extended cytoplasmic processes into the extracellular matrix and that lumina were present even at the distalmost tips of the vessels. Solid cords of endothelial cells were not seen. We concluded that in proliferative diabetic retinopathy, new vessels develop by a process of focal extracellular matrix degradation, generalized and exuberant extracellular matrix production, cytoplasmic microvillus extension into the extracellular matrix, and active lumen formation.

Ninety-five patients (104 eyes) were enrolled in a pilot study of subconjunctival 5-fluorouracil (5-FU) injections after filtering surgery in eyes with poor surgical prognoses. At least a six-month follow-up was available on 84 patients, of whom four were excluded from the analysis of surgical outcome because they suffered retinal detachments within six months of their filtering surgery. The initial 5-FU procedures on the remaining 80 patients were successful (no further glaucoma surgical procedures were either performed or recommended, and the intraocular pressures [IOPs] were either 21 mmHg or lower with ocular hypotensive medication[s] or 25 mmHg or lower without ocular hypotensive medication) in 33 (68%) of the 48 aphakic eyes with non-neovascular glaucomas, 13 (81%) of the 16 phakic eyes with non-neovascular glaucomas after unsuccessful filtering surgery, and 12 (75%) of the 16 eyes with neovascular glaucoma (NVG). The follow-up on the successful eyes ranged from 6 to 34 months (mean +/- SD = 18.5 +/- 7.5). The visual acuities remained within one line of their preoperative levels or improved in 38 (79%) of the 48 aphakic eyes with non-neovascular glaucoma, 11 (69%) of the 16 phakic eyes with non-neovascular glaucoma after unsuccessful filtering surgery, and 12 (75%) of the 16 eyes with NVG. The initial 5-FU procedures on the 104 eyes were complicated by the following: corneal epithelial defects (50%); conjunctival wound and suture tract leaks (36%; 2% underwent surgical repair); suprachoroidal hemorrhages (9%); retinal detachments (3%); subepithelial corneal scarring (3%); endophthalmitis (2%); and malignant glaucoma (1%). It is the authors' impression that postoperative subconjunctival 5-FU increases the likelihood of achieving IOP control after filtering surgery in eyes with poor surgical prognoses; however, a randomized clinical trial is necessary to confirm this impression.

During the past two decades, the number of diabetic patients requiring vitrectomy for nonresolving vitreous hemorrhage has decreased four-fold, whereas there has been a substantial increase in diabetic patients with traction and combined traction/rhegmatogenous retinal detachment (RD) requiring surgery. Additional contemporary surgical indications are progressive fulminant neovascular proliferation, massive preretinal hemorrhage, massive fibrin response, and progressive retrolental fibrovascular proliferation. Surgical techniques for management of tractional detachments have evolved from circumscription of tractional epicenters to en bloc removal of all proliferative tissue.

Retinal revascularization developed within the treatment scar in 7% of patients who had laser photocoagulation treatment for a choroidal neovascular membrane. This revascularization could be mistaken for recurrent choroidal neovascularization because it initially proliferated into a glomerularlike structure and showed dye leakage on angiography. Unlike choroidal neovascularization, these vessels, however, filled entirely from the retinal circulation and stereoscopic angiograms showed them to be located in the inner retina. In the 20 patients who were followed up, the retinal revascularization first appeared approximately four weeks after treatment and persisted for an average of ten weeks. It was associated with dense laser scarring, retinal capillary obliteration, and internal limiting membrane wrinkling, suggesting that heavy initial laser treatment was a predisposing factor for its development. It is important to differentiate retinal revascularization, which has an excellent prognosis and does not require re-treatment, from recurrent choroidal neovascularization, which usually must be treated promptly to avoid loss in visual acuity.

A 22-year-old Japanese woman with systemic sarcoidosis had retinal neovascularizations at seven loci with repeated vitreous hemorrhage in her right eye. Oral administration of prednisone was not effective. However, argon laser photocoagulation to the neovascularizations obliterated the neovascular fronds except at the optic nerve head; three months from the treatment, the neovascularization at the optic nerve head regressed spontaneously. No serious complications have occurred, and the vitreous hemorrhage has not recurred for the past two years. From these results, argon laser photocoagulation was thought to be effective for the treatment of retinal neovascularization in sarcoidosis.

A 61-year-old woman presented with a superior papillary branch artery obstruction occurring secondary to an intra-arterial embolus. Thirteen months later she developed neovascularization of the optic disc and retina in the same eye. Although the situation is unusual, this case suggests that retinal branch artery obstruction may rarely predispose to ocular neovascularization.

The authors treated 1007 eyes with vitrectomy for complications of proliferative diabetic retinopathy. Indications for surgery were: vitreous hemorrhage, 353 eyes (35%); traction retinal detachment, 360 eyes (36%); combined traction-rhegmatogenous retinal detachment, 172 eyes (17%); and other progressive fibrovascular proliferation 122 eyes (12%). During the study period, the frequency of vitreous hemorrhage as an indication for surgery decreased from 42 to 25%, and other progressive fibrovascular proliferation increased from 5 to 22%. The frequency of traction and traction/rhegmatogenous retinal detachments did not change. The results of surgery varied according to the indication. Seventy-nine percent of eyes with vitreous hemorrhage obtained final vision of 5/200 or better. Similar results were obtained in 64% of eyes with traction detachment, 56% of eyes with rhegmatogenous detachment, and 81% of eyes with progressive fibrovascular proliferation. The percentage of eyes achieving final vision of 20/100 or better are as follows: vitreous hemorrhage, 48%; traction detachment, 27%; rhegmatogenous detachment, 24%; and progressive fibrovascular proliferation, 46%. The success rate improved in each anatomic category during the last 3 years of the study.

During a ten-year period, we treated 241 eyes by transscleral ruby laser cyclocoagulation. Each eye had a minimum follow-up of six months. The average was 24 months and the range was six to 92 months. Using a criterion for success of intraocular pressure between 5 and 22 mm Hg, we achieved an overall success rate of 62% (150 of 241 eyes). This success rate varied from 86% for aphakic open-angle glaucoma (32 of 37 eyes) to 53% for neovascular glaucoma (72 of 135 eyes). Most eyes with useful vision preoperatively maintained these levels. Chronic hypotony (41 eyes) and phthisis (17 eyes) were the most frequent complications, although phthisis was common only in the neovascular glaucoma group (13 eyes). The visual results are more favorable and the need for retreatment and postoperative medications is less than with cyclocryotherapy, and postoperative discomfort is considerably reduced.

Patients with long-standing diabetes develop acquired colour vision defects in parallel with retinal vascular changes. This may take the form of an overall loss of hue discrimination or a specific tritan (blue) defect. A battery of colour vision tests can be used to monitor the different features of diabetic retinopathy and to assess the effects of treatment. Diabetic disc new vessels form when approximately a quarter of the retina is ischaemic. The colour vision defect in these patients is usually severe and is frequently tritanopic. The effect of both argon laser and xenon arc panretinal photocoagulation is to increase the severity of the colour defect. All the eyes examined were tritanopic after treatment and did not recover during the 12-month follow-up period. The severity of this acquired colour vision defect can result in practical difficulties for the patient.

The Idiopathic Neovascularization Study is a multicenter controlled clinical trial designed to determine whether argon laser photocoagulation is useful in preventing severe visual loss in eyes with a choroidal neovascular membrane (NVM) and no other clinically significant eye disease. Patients with an NVM 200 to 2,500 microns from the center of the foveal avascular zone were randomly assigned to argon laser photocoagulation (n = 33) or to observation (n = 34) groups. While the sample size of 67 eyes is insufficient to yield independent, definitive results, the pattern of treatment benefit is similar to that observed in two other controlled trials of argon laser photocoagulation of NVMs, the Senile Macular Degeneration Study and the Ocular Histoplasmosis Study. It is reasonable to conclude that patients with idiopathic NVMs, treated according to study protocol, may derive a similar benefit.

Photofield mapping is a useful method for classifying subretinal neovascularization based on its area and location. Careful central field mapping is performed to delineate scotomata during evaluation of patients with subretinal new vessels. A photofield map is then constructed by projecting 35 mm fundus photographs and angiograms onto an appropriately-oriented central visual field map. The composite map (photofield) documents the location and relationship of scotomata, subretinal neovascularization, foveal avascular zone, and retinal blood vessels. The areas of subretinal neovascularization and scotomata are measured in square millimeters with a planimeter. The distance between their closest edge and the center of the foveal avascular zone is measured in millimeters. This method permits quantitative comparison of results with different photocoagulation protocols and instrumentation. Such comparative analysis may help improve the technique and instrumentation used in laser photocoagulation of subretinal neovascularization.