Ab interno retinochoroidectomy in primates.

Primates underwent the ab interno removal of up to a 6 X 7-disc diameter area of the retina and choroid adjacent to the optic disc. The area of resection was treated three weeks before surgery with an encircling row of xenon arc photocoagulation. Surgery involved photocoagulation of the entire resected area and removal of the retina and choroid using a wide-angle cutter vitrophage.

A simplified technique for the removal of liquid silicone from vitrectomized eyes.

We describe a simplified technique for the removal of liquid silicone from the vitreous cavity. With the patient under local anesthesia, sodium hyaluronate is injected intravitreally, and liquid silicone is allowed to exit the eye through an open pars plana sclerotomy or limbal incision. Vitreous lavage is then performed with vitrectomy infusion solution.

Fibronectin in alkali burns of the rabbit cornea.

Alkali burns of the cornea were made bilaterally in 16 albino rabbits. The eyes were then treated four times a day in a masked fashion with a solution either of fibronectin (250 micrograms/ml) plus gentamicin (1.5 mg/ml) or of gentamicin (1.

Ten years experience with eye wall resection for uveal malignant melanomas.

Thirty-four patients underwent eye wall resection for choroidal malignant melanoma over a period of more than ten years. Of these, 11 eyes were later enucleated for complications. Average mean follow-up has been more than 5.

Choroidal detachment and ocular hypotony: CT evaluation.

The computed tomographic (CT) findings in 20 patients with hemorrhagic choroidal detachment, serous choroidal detachment, and/or ocular hypotony are described. Hemorrhagic choroidal detachment appeared as an area of high attenuation that was usually localized, uniformly hyperdense, and not position-dependent (i.e.

Vitrectomy and intravitreal antiviral drug therapy in acute retinal necrosis syndrome. Report of two cases.

Two patients with acute retinal necrosis were treated with vitrectomy, intravitreal infusion of acyclovir, and prophylactic scleral buckling procedures. Both patients have had a uneventful postoperative course and a recovery of visual acuity; follow-up has been at five and 14 months. There has been no sign of toxicity from the intravitreally administered acyclovir by electroretinographic or clinical criteria.

Toxicity of antineoplastic drug combinations in vitrectomy infusion fluid.

We evaluated a combination of various antineoplastic drugs used in vitrectomy infusion fluid for toxicity. A combination of 250 micrograms/ml of 5-fluorouracil with each of the following agents, 8.0 micrograms/ml of thiotepa or 40 micrograms/ml of etoposide, or 0.

Effects of the CW YAG laser on the human iris and retina.

A CW YAG laser was used to coagulate retina and to produce an optical iridotomy in a human eye that was to be enucleated for malignant melanoma at the optic nerve head. Moderate coagulation with the CW YAG laser produced a deep choroidal reaction involving the outer portion of the retina. The inner structure of the fovea remained relatively unaffected.

Retinochoroidectomy ab interno.

We evaluated the possibility of using an internal approach to surgically remove a part of the retina and choroid. Preoperative photocoagulation and the use of an endolaser and the vitrophage enabled us to perform retinochoroidectomy ab interno successfully in experimental animals.

Evaluation of intravitreal 5-fluorouracil, vincristine, VP 16, doxorubicin, and thiotepa in primate eyes.

A single intravitreal dose of 750 micrograms 5 fluorouracil (5 FU) or 5 micrograms doxorubicin were nontoxic to primate eyes. A concentration of 250 micrograms/ml of 5 FU in the vitrectomy infusion fluid in combination with 8 micrograms/ml of thiotepa, with 40 micrograms/ml of VP16 (etoposide), or with either .04 or .

Toxicity of intravitreal antiviral drugs.

Two systemic agents, vidarabine and acyclovir, were tested for ocular toxicity in intravitreal injection and vitrectomy infusion solutions. On the basis of this study we recommend using up to 30 mcg/0.1 ml of vidarabine as an intraocular injection or 8 to 16 mcg/ml in vitrectomy infusion fluid.

Effect of CW YAG and argon green lasers on experimentally detached retinas.

We evaluated the effects of argon-green (514.5 nm) and CW neodymium YAG (1060 nm) wavelengths on experimentally detached retinas of primates. Neither laser produced damage to the sensory retina of the fovea.

Histopathologic studies on transscleral argon-krypton photocoagulation with an exolaser probe.

We performed argon and krypton laser photocoagulation of the retina and ciliary body on rabbit and monkey eyes using an exolaser probe. Clinically, transscleral retinal lesions produced a white circumscribed reaction. Histologically, we observed necrosis of the retina and choroid.

Vitrectomy and Whipple's disease.

We diagnosed Whipple's disease from the vitreous aspirate of two patients who underwent vitrectomies . In one case, the vitrectomy specimen would have indicated the diagnosis three years before the jejunal biopsy was performed had the appropriate PAS stain been used. In the second case, the PAS-positive macrophages were identified at the time of surgery.

Evaluation of toxicity of intravitreal antineoplastic drugs.

We evaluated the toxic and nontoxic doses of eight antineoplastic drugs in the vitreous cavity of rabbits. These drugs may have implications in the prevention of cell proliferation in the vitreous.

Retinal microincarceration with penetrating diathermy in the management of giant retinal tears.

A technique for repair of giant retinal breaks with detachment involves the performance of lensectomy-sector iridectomy, vitrectomy, and scleral buckling behind the equator. Total fluid-gas exchange is performed while the patient is turned to the prone position on a rotating table. Penetrating diathermy is used to fix the retina and to create retinal microincarceration while air is simultaneously injected into the eye.

Ocular effects of various laser wavelengths.

Lasers have become an indispensable tool in management of many ocular disorders. This review describes the principles of lasers and the effects various laser modalities and wavelength modalities can produce on ocular structure. Guidelines are provided for appropriate selection of various wavelengths and prevention of complications of the laser treatment.

Computed tomography in choroidal detachment.

Computed tomography proved valuable in localizing and differentiating serous or hemorrhagic choroidal detachment and scleral infolding. The mean attenuation values (CT numbers) in the region of fresh hemorrhagic choroidal detachment were 74 Hounsfield units (HU). The 90% confirmation limit of the mean was 55 to 84 HU.

Contact lenses for Nd:YAG application in the vitreous.

A set of convex-surfaced contact lenses with radii of 12.5 mm, 18 mm, and 25 mm has been developed for Nd:YAG laser work in the vitreous cavity. The lenses reduce the energy threshold for plasma formation and increase the safety of intraocular YAG laser use.

Limitation of iris and ciliary body resection in primates.

The authors evaluated the limitation of iridocyclectomy in primate eyes. Six-clock-hour resections were tolerated and the intraocular pressure was reestablished to preoperative levels (17 mm Hg) within 1 month after surgery. Seven- to eight-clock-hour resections were also tolerated by the eyes, but the intraocular pressure remained low (7-10 mm Hg) for the extent of the study (5 months).

Evaluation of a new silicone-methane polymer contact lens.

A new gas permeable contact lens is produced using a solid silicone core and a plasma polymer surface. This surface is hydrophilic and impermeable to macromolecules. The surface characteristics of this lens were compared with the surface characteristics of available silicone contact lenses.

Aphakic cystoid macular edema in children after vitrectomy for anterior segment injuries.

Twenty-four children had surgery utilizing vitrectomy instrumentation for anterior segment trauma. Lensectomy was performed in 23 of 24 eyes. In each child a pars plicata approach was used.