Stanley S. Schocket

Deferoxamine (Desferal®)-induced Toxic Retinal Pigmentary Degeneration and Presumed Optic Neuropathy

Eight patients (16 eyes) developed ocular toxicity while undergoing intravenous deferoxamine mesylate (Desferal) chelation therapy for transfusional hemosiderosis. Presenting symptoms included decreased visual acuity, color vision abnormalities, and night blindness. Six patients presented as presumed retrobulbar optic neuropathy demonstrating central scotomas and color vision abnormalities. The remaining two patients presented with pigmentary changes confined either to the macula or equator. Following cessation of therapy, vision improved in all but four eyes, which did not attain their pretreatment visual acuity. Optic neuropathy resolved in all cases. However, follow-up revealed development of retinal pigmentary degeneration in seven patients, involving the macula in six and the equatorial retina in one. Fluorescein angiography and electrophysiological tests suggested toxicity at the level of retinal pigment epithelium and photoreceptors.

Anterior Chamber Tube Shunt to an Encircling Band in the Treatment of Neovascular Glaucoma and other Refractory Glaucomas: A Long-term Study

Long-term follow-up results of the anterior chamber tube shunt to an encircling band (ACTSEB) procedure are reported. Thirty eyes of 28 patients with neovascular glaucoma (Group I) and five eyes with non-neovascular refractory glaucoma (Group II) underwent this procedure. In Group I, the average preoperative intraocular pressure (IOP) was 57.1 mmHg. After surgery and average followup of 25 months 96% of eyes had a successful outcome with an average IOP of 15.8 mmHg (P less than 0.001). In Group II, despite multiple glaucoma surgical procedures, the average preoperative IOP was 54 mmHg. After surgery and average followup of 20 months 80% of eyes had a successful outcome with an average IOP of 19.8 mmHg (P less than 0.01). Revisions in our surgical technique utilizing a small entry with a 25-gauge needle into the anterior chamber and use of Healon resulted in a fully formed anterior chamber by two days. Clinical and experimental evidence is presented which suggest that aqueous filters through the tube to a reservoir around the encircling band.

Clindamycin in the Treatment of Toxoplasmic Retinochoroiditis

We treated 26 patients with acute toxoplasmic retinochoroiditis with clindamycin between 1974 and 1982. Four patients were treated with clindamycin alone and 17 with clindamycin and prednisolone. Five patients received clindamycin and prednisolone, sulfadiazine, pyrimethamine, or cryocoagulation, or a combination of these. All patients with the acute disease had the characteristic foci and a positive titer on the Sabin-Feldman dye test of at least 1:16. Other causes of retinochoroiditis were excluded. All but two patients, who developed diarrhea after two weeks, received clindamycin for a minimum of three weeks. All patients improved after two weeks of treatment, but two patients with lesions larger than 2 disk diameters required an additional six weeks of treatment to heal completely. During follow-up periods ranging from 18 months to seven years (mean, three years) there have been only two recurrences (7.7%). Complications with clindamycin treatment were limited to gastrointestinal upsets, diarrhea, and skin rash. There were no cases of pseudomembranous colitis, the most serious reported complication of clindamycin use.

Intraoperative Massive Suprachoroidal Hemorrhage during Pars Plana Vitrectomy

Seven eyes (7 patients) developed massive suprachoroidal hemorrhage (MSCH) during pars plana vitrectomy (PPV) for complicated retinal detachments. The MSCH developed late in the procedure following PPV, air fluid exchange, endolaser, cryopexy, and scleral buckling in five of seven eyes. In two eyes, mild hemorrhagic choroidal detachments noted intraoperatively progressed to MSCH within 72 hours postoperatively. Diagnosis of MSCH was confirmed by echography and CT scan. Multiple scleral buckling surgeries, high myopia, aphakia, and intraocular inflammation were the main risk factors. Placement of a broad posterior scleral buckle with intraoperative hypotony and cryopexy were important precipitating factors. Visual results were poor, with six of seven eyes showing no light perception. The mean follow-up time was 12.8 months. Once acute MSCH is recognized intraoperatively, surgical decompression at that time should be avoided as MSCH itself may tamponade the choroidal bleed. Details of prevention and management are discussed.

Laser treatment of macular holes.

Macular holes have not been treated with the laser because of the rarity of subsequent total retinal detachment (RD). The authors attempted to clear the subretinal fluid of the halo by laser coagulation of the rim of the hole. Eighteen eyes with visual acuity of 20/200 or less were treated with a laser and followed for a mean of 34.8 months. Ten eyes (55.6%) improved three to eight lines, five eyes (27.8%) remained the same, and the vision of three (16.6%) deteriorated three to five lines. The best visual results noted in three eyes (20/400-20/70, 20/200-20/80, and 20/200-20/60) correlated with the least late loss of pigment epithelium and pigment migration.

Transient Myopia and Accommodative Paresis Following Retinal Cryotherapy and Panretinal Photocoagulation

Loss of accommodation, transient myopia, or both, were complications following retinal cryotherapy in two eyes and after panretinal photocoagulation in six eyes (seven patients). A 17-year-old young man had these refractive difficulties one week after cryotherapy for retinal holes. His accommodative amplitude measured 1.0 D in the treated eye and 8.0 D in the untreated eye. One week later he received cryotherapy to the previously untreated eye, reducing that accommodative amplitude to 2.5 D. Accommodative paresis and transient myopia resolved without treatment within five weeks. Six other patients (six eyes, seven episodes) with an average age of 33 years demonstrated accommodative loss (40% to 92% decrease, average decrease 64%), transient myopia, or both, after panretinal photocoagulation for proliferative diabetic retinopathy. All patients recovered without treatment within six weeks (average, 22 days). All young patients should be made aware of this transient, but troublesome complication before treatment.

SIDEROSIS FROM A RETAINED INTRAOCULAR STONE

A penetrating intraocular stone caused a retinal detachment that was repaired successfully. The patient returned 18 months later with siderosis bulbi. The patient was followed by serial neurosensory tests for the next three years. The electro-oculogram (EOG) showed the greatest abnormality, while the electroretinogram (ERG) and dark adaptation, although initially affected, showed no further deterioration. Surgical procedures on this eye included linear extraction of the siderotic lens, anterior vitrectomy, and irrigation of a hyphema. Fluorescein angiogram revealed a siderotic deposit on the retina. Progressive visual field loss prompted removal of the stone foreign body by an eye-wall resection technique. Five years later vision was 20/30. While dark adaptation, EOG, and ERG remained stable, the visual fields showed progressive constriction. Fluorescein angiogram revealed pigment epithelial defects, cystoid macular edema, reduced peripheral circulation, and progressive clearing of the retinal iron deposits.

Pseudophakic and aphakic retinal detachment mimicking cystoid macular edema

Seventeen eyes of patients who were being followed by their ophthalmologists for aphakic (8 eyes) or pseudophakic (9 eyes) cystoid macular edema (CME) were examined on referral. All eyes showed retinal detachment (RD), and eight eyes had CME with RD. Most RDs were inferior and shallow. Proliferative vitreoretinopathy (PVR) was noted in 15 eyes (88.2%). There was history of vitreous loss during the last intraocular surgery in 88.2% eyes. Visual acuity ranged from 20/40 to hand movements. Fundus view was hazy in most eyes, and indirect ophthalmoscopy was most useful in detecting RD. Retinal reattachment with scleral buckling and/or vitrectomy was achieved in 16 eyes (94.1%). Postoperative visual recovery was jeopardized due to longstanding macular detachment of greater than 1 month in 11 eyes (64.7%). Eight eyes (47%) achieved 20/50 vision whereas 25% did not improve to better than 20/400. Factors leading to failure in making the correct diagnosis and their prevention are discussed.

Posterior Capsulotomy as a Complication of Indirect Laser Photocoagulation

Two pseudophakic patients with posterior chamber intraocular lens implants and intact posterior capsules underwent indirect laser photocoagulation during their immediate postoperative period (24 and 72 hours postoperatively, respectively). Laser treatment was indicated for a retinal break noted after vitrectomy and scleral buckling in one patient and after peribulbar perforation during cataract extraction in the other patient. Ocular media were hazy because of vitreous haze and hemorrhage in both eyes and higher power laser settings were required to produce adequate chorioretinal burns during photocoagulation. Inadvertent large posterior capsulotomy as a complication was noted in both eyes. High-power settings and hazy ocular media are risk factors toward this complication. We recommend that slit-lamp examination be performed before, during, and after indirect laser treatment, especially when higher power settings are required.