Follow-up study in eyes with choroidal neovascularization caused by presumed ocular histoplasmosis

Acute zonal occult outer retinopathy (AZOOR) associated with multifocal choroidopathy

Acute zonal occult outer retinopathy (AZOOR) may be precipitated by various retinal disorders and is characterised by rapid loss of visual field which cannot be explained by the ophthalmoscopic changes consequent upon the initiating disease. The electroretinogram is abnormal, indicating that the field loss is due to retinal dysfunction. The phenomenon was first recognised in the multiple evanescent white dot syndrome (MEWDS) as the enlarged blind spot syndrome. It was subsequently described with multifocal inner choroidopathy and acute macular neuropathy (AMN). We have identified 7 patients who presented with widespread visual loss associated with multifocal inner choroidopathy in whom functional loss was documented with electroretinography and automated visual field testing. All patients were young, myopic, and otherwise healthy women. Initial photopsia was noted by 4 patients. Fundus findings included scattered small partially pigmented yellowish lesions resembling those in multifocal inner choroidopathy or pseudo presumed ocular histoplasmosis syndrome, disc swelling, vitritis, and secondary choroidal neovascularisation. Two patients had bilateral involvement. All patients had an enlargement of the blind spot, and widespread visual field loss which was not explained by fundus changes. All had an abnormal electroretinogram suggesting widespread retinal disease. In AZOOR retinal dysfunction occurs without corresponding visible retinal lesions. This disorder appears to be precipitated by several conditions, although the causal relationship between the initiating event and the widespread functional loss is unknown.

Choroidal neovascularization in children: report of five cases and literature review

Choroidal neovascularization is rare in the pediatric population. It has been associated in this age group with a variety of conditions. Increasing ability to treat these neovascular lesions with laser photocoagulation makes early recognition very important for visual preservation. An overview is presented, including an updated list of conditions associated with choroidal neovascularization in children and adolescents. Guidelines to recognition, parent and patient instructions, and the selective use of fluorescein angiography are emphasized. Five illustrative cases are highlighted, including a 10-year-old boy successfully treated with krypton laser photocoagulation near the fovea.

Idiopathic sub-retinal neovascular membranes in the macula (hemorrhagic macular choroidopathy of young adults). Clinical report and effectiveness of laser treatment

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.

Choroidal neovascularization

Choroidal neovascularization is now considered to be a most important feature in the pathogenesis and treatment of a number of chorioretinal disorders. Since the recognition of its importance, choroidal neovascularization has been described in clinical and pathologic studies of a variety of different ophthalmologic conditions. We have summarized the diseases in which choroidal neovascularization occurs and have reviewed studies on the natural history, clinical findings, and therapy of choroidal neovascularization that provide the basis for the current management of this condition.

Ocular histoplasmosis syndrome

The Macular Photocoagulation Study (MPS) is a multi-center clinical trial supported by the National Eye Institute whose purpose is to assess argon laser photocoagulation as a treatment for choroidal neovascular membranes (NVMs) that do not involve the fovea. The MPS documented that in patients with ocular histoplasmosis syndrome argon laser photocoagulation in comparison with no treatment can reduce the risk of severe visual loss from 46 to 13% in the first two years. Accordingly, patients with ocular histoplasmosis and NVMs outside the fovea are advised to undergo prompt treatment with argon laser photocoagulation.

Subfoveal and juxtafoveal subretinal neovascularization in the presumed ocular histoplasmosis syndrome. Visual prognosis

The visual prognosis of 148 eyes in patients with an active subfoveal or juxtafoveal subretinal neovascular membrane (SRNVM) in the presumed ocular histoplasmosis syndrome (POHS) was reviewed. Average follow-up was 39 months. One hundred twenty of 148 eyes (81.1%) had a final visual acuity worse than 20/40. One hundred three of 148 eyes (69.6%) had a final visual acuity equal to or worse than 20/200. Systemic and/or periocular steroids had no effect on final visual outcome. Factors affecting final visual outcome are described and prognosis in the fellow eye is discussed.

Visual prognosis of disciform degeneration in myopia

A retrospective study was done on a consecutive series of patients presenting to the Moorfields Eye Hospital with visual reduction secondary to angiographically proven subretinal neovascularization associated with myopia (Förster-Fuchs' spot), with a short history of visual loss, and free of other ocular disease. The visual acuity at follow-up was compared to that at presentation, and related to size and location of the neovascular complex, as well as patient age, and duration of follow-up. The results show a generally poor prognosis in that 43% of the patients lost two or more lines of vision, while 60% were less than or equal to 6/60 at last follow-up. As expected there was a direct relationship between visual acuity and the distance of the neovascular tissue from the fovea, and an inverse relationship between acuity and the size of the lesion. There seems to be a short neovascular growth phase, with early visual loss.

Follow-up study of presumed ocular histoplasmosis syndrome

One hundred and sixty-two patients with presumed ocular histoplasmosis syndrome were evaluated. New macular scars not present on initial angiogram developed in 9% of eyes. The risk of developing a symptomatic macular lesion in eyes with asymptomatic macular scars was 23%. In eyes with peripapillary scarring, 3.8% developed a peripapillary neovascular membrane. Follow-up was 5.5 years. When the neovascular membrane was touching or outside the foveal avascular zone, the difference between photocoagulated and control eyes was not statistically significant. When only adequately photocoagulated eyes (20) were compared with control eyes (40), the difference was statistically significant (P = 0.04).

Peripapillary neovascular membranes in presumed ocular histoplasmosis

We studied 39 eyes with ocular histoplasmosis and peripapillary neovascular membranes for an average of 12 months. On the basis of clinical findings, 19 were selected for treatment with photocoagulation. Of the treated eyes, 12 (63%) had a visual result of 6/12 (20/40) or better. Of the 20 untreated eyes, six were clinically untreatable and 14 were electively followed up. All but one of the eyes electively followed up had a good visual result. Proximity of the neovascular membrane to the fovea was the most important prognostic factor in determining visual outcome. All eyes with membranes less than 1/4 disk diameter from the fovea lost central vision. All membranes greater than one disk diameter had excellent results. The indications for treatment were prolonged serous or hemorrhagic detachment of the fovea, documented progression of the membrane, and possibly, loss of central vision in the fellow eye from peripapillary disease. Residual and recurrent neovascularization were significant treatment complications.

Results of argon laser photocoagulation in presumed ocular histoplasmosis

We performed argon laser photocoagulation on 31 eyes of 30 patients with presumed ocular histoplasmosis. Nineteen of 25 eyes (76%) with neovascular membranes 0.25 disk diameter or further from the fovea had 6/12 (20/40) or better vision after an average follow-up period of 20 months. Twenty-two of these eyes (88%) had the same or improved visual acuity during this period. When compared to a similar group of untreated eyes, the apparent advantage of photocoagulation in preserving visual acuity was not statistically significant.