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We investigated the use of tissue plasminogen activator (t-PA) as an adjunct to the surgical removal of subfoveal choroidal neovascular membranes. t-PA in a concentration of 6 micrograms/0.1 cc dissolved the fibrin rim surrounding recent subfoveal membranes but was less effective on more mature lesions. t-PA may be a useful intraoperative tool to limit the damage to surrounding structures during the surgical excision of recent subfoveal choroidal neovascular membranes with surrounding fibrin rims.

Indocyanine green (ICG) is a dye with an absorption peak (795 to 810 nm) similar to the emission peak of the diode laser (805 nm). Therefore, ICG dye-enhanced diode laser photocoagulation may permit the selective ablation of ICG-retaining choroidal neovascular membranes (CNVM) with relative sparing of the neighboring neurosensory retina. Ten patients with poorly defined subfoveal CNVM were treated with ICG dye-enhanced diode laser photocoagulation and followed for an average of 15 months. One of the 10 patients experienced an immediate significant drop in visual acuity after photocoagulation. Obliteration of the CNVM at the site of laser photocoagulation was confirmed by fluorescein angiography and ICG angiography. Subfoveal chorioretinal scar formation was noted postoperatively in all 10 patients. At last follow up, 9 of these 10 patients had no more than a two-line increase or decrease in visual acuity. These preliminary results suggest that poorly defined subfoveal CNVM can be successfully treated by ICG dye-enhanced diode laser photocoagulation with minimal adverse affect on visual acuity in most cases.

Subretinal neovascular membranes located under the fovea typically lead to significant visual loss. Laser treatment has been limited due to the anatomic location of the neovascular process, but surgical removal has been reported with promising results. We surgically removed a long-standing, presumed ocular histoplasmosis syndrome (POHS) subfoveal neovascular membrane that had been present for 10 months in a patient's only functional eye, with unexpected good results. This case suggests that the good visual outcomes achieved by surgically excising smaller subfoveal neovascular membranes early in their natural history also can be achieved in selected patients with more chronic and severe subfoveal neovascular processes.

We prospectively studied the safety and efficacy of subfoveolar laser treatment of choroidal neovascular membranes (CNVM) in 29 eyes. With one to four treatments, all CNVMs were successfully eradicated. Central visual acuity improved in 31% and stabilized in 69%. Vision did not deteriorate in any of the eyes. In appropriately selected eyes, subfoveolar treatment appears safe and effective in halting the exudative response and minimizing scotoma size, thus facilitating the use of low-vision aids.

A patient who developed intravitreal ciliary body neovascularization following cyclocryotherapy for neovascular glaucoma is presented. Presenting vitreous hemorrhage limited her visual acuity to 20/200. After panretinal photocoagulation, the intravitreal ciliary body neovascularization regressed, the vitreous hemorrhage cleared, and the patient's visual acuity was 20/30. The possible pathogenesis of intravitreal ciliary body neovascularization is reviewed, and the reason for regression of the neovascular tissue is hypothesized.

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.

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.

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.

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.