The effect of topical retinoic acid (Etretinate) on mouse conjunctival Langerhans cells.

Four groups of BALB/c mice were treated locally with different concentrations (0.1-1.0%) of retinoic acid (Etretinate) ointment for a period of one to four weeks.

Histopathologic findings in congenital grouped pigmentation of the retina.

Background: Congenital grouped pigmentation of the retina is a condition characterized by multiple, well-circumscribed, flat, pigmented fundus lesions clustered in a fashion resembling "bear tracks."

Methods: Light and electron microscopy was used to study these lesions in an eye of a 2-year-old boy. The eye was enucleated for retinoblastoma.

Retinal tolerance of an implantable light source for use during vitrectomy surgery.

To assess for the possible development of a phototoxic lesion, we exposed five Dutch belted rabbit retinas to constant illumination with an implantable "chandelier" light source at maximal intensity for 1 hour. No clinically apparent lesion developed in any of the experimentally treated eyes by 48 to 72 hours posttreatment. Light and electron microscopic examination failed to reveal any of the characteristic changes of retinal phototoxicity.

Changes in aqueous outflow after in vitro neodymium: yttrium aluminum garnet laser cyclophotocoagulation.

To examine the possible role of transscleral outflow routes, enucleated human and porcine eyes underwent noncontact neodymium:yttrium aluminum garnet (Nd:YAG) laser cyclophotocoagulation 3 mm posterior to the limbus. Pars plana lesions were verified histologically. The eyes were perfused with saline solution at 50 mm Hg perfusion pressure, placing the tip of the needle into the hyaloid orbicular space.

Congenital hypertrophy of the retinal pigment epithelium. Electron microscopic and morphometric observations.

Congenital hypertrophy of the retinal pigment epithelium (CHRPE) is a well-circumscribed, flat, pigmented fundus lesion that is stable and generally nonprogressive. Light and electron microscopy and morphometric analysis was used to study a lesion with the clinical characteristics of CHRPE found in an eye enucleated for a posterior segment malignant melanoma. These studies showed that the lesion was composed of tall, maximally pigmented RPE cells that had a density 1.

Rod cell-specific antigens in retinoblastoma.

We investigated rhodopsin immunoreactivity in five well-differentiated retinoblastomas using a panel of monoclonal antibodies directed against specific antigenic sites in the amino- and carboxyl-terminal portions of rhodopsin. All five monoclonal antibodies bound to the rod cell outer segment of nontumorous retina in all 10% formaldehyde solution-fixed, paraffin-embedded tissue sections. A characteristic "halo" cell surface staining pattern was observed in four (80%) of five tumors treated with two monoclonal antibodies, B6-30 (rhodopsin amino-terminal specific) and K16-107 (rhodopsin carboxyl-terminal specific).

Human IRBP: characterization of uveitopathogenic sites.

Human interstitial or interphotoreceptor retinoid binding protein (IRBP) is a 136,000 molecular weight photoreceptor cell protein capable of inducing an experimental autoimmune uveitis (EAU) in susceptible animal strains. In order to determine specific sites in human IRBP responsible for its uveitopathogenicity, we synthesized 60 peptides, corresponding to its entire 1262 amino acid sequence, and tested each peptide for its ability to induce an EAU in Lewis rats. Three peptides with extensive amino acid sequence homology, designated HIRBP 715, HIRBP 730, and HIRBP 745, were uveitopathogenic when used at a 50 micrograms immunizing dose.

Orbital involvement with desmoplastic melanoma.

A 79-year-old woman developed an orbital mass five and a half years after excision of a cutaneous melanoma from the side of the nose. The initial orbital biopsy was interpreted histopathologically as a malignant fibrous histiocytoma, but special stains and electron microscopy showed it to be a desmoplastic malignant melanoma which had apparently spread to the orbit from the prior skin lesion by neurotropic mechanisms. The occurrence of a desmoplastic neurotropic melanoma in the orbit has not been previously recognised.

Oncocytoma of the caruncle.

The oncocytoma (oxyphil adenoma) is an uncommon tumor composed of transformed epithelial cells of the ducts of salivary glands and other organs. In two men, 66 and 75 years old, oncocytomas originated in the caruncle where they assumed rather characteristic features. The caruncular oncocytomas clinically appeared to be cystic.

Orbital neurilemoma with extension through the superior orbital fissure.

An otherwise healthy 33-year-old man developed slowly progressive unilateral proptosis. Computed tomography demonstrated a large orbital mass extending posteriorly through the superior orbital fissure. The encapsulated tumor, including the portion within the superior orbital fissure, was completely removed by a lateral orbitotomy.

Immunohistochemical and ultrastructural study of unusual IgM lambda lymphoplasmacytic tumor of the lacrimal gland.

A 72-year-old man developed a slowly enlarging mass involving the left lacrimal gland. Excisional biopsy disclosed a lymphoplasmacytoid tumor which was found by immunohistochemistry techniques to be a monoclonal proliferation, expressing cytoplasmic IgM lambda. However, serum protein immunoelectrophoresis disclosed a monoclonal spike in the gamma-globulin region with IgG lambda.

Rhodopsin and retinoblastoma. A monoclonal antibody histopathologic study.

Rhodopsin was identified in formaldehyde-fixed, paraffin-embedded human fetal retina, and in five retinoblastomas using monoclonal antibody (MAb) MAb-E. The binding pattern corresponding to rhodopsin immunoreactivity was then compared with S-antigen using another monoclonal antibody, MAbA9-C6. Rhodopsin and S-antigen were first observed in the 18-week-old human fetal eye, at a stage preceding photoreceptor differentiation.

Antigenic and cellular heterogeneity of primary uveal malignant melanomas.

Monoclonal antibody (MAb) MAb8-1H, which identifies an ocular melanoma-associated antigen, and computer-assisted cytomorphometric analysis were used to investigate antigenic and cellular heterogeneity in four atypical cases of choroidal or ciliary body melanoma. The presence of one or more well-localized, morphologically distinct areas within each uveal melanoma, suggestive of multiple tumor cell populations, was observed by conventional light microscopy. In one choroidal melanoma with an unusual bilobed configuration, MAb8-1H bound only to the anterior lobe composed of spindle melanoma cells.

Tissue distribution and biochemical properties of an ocular melanoma-associated antigen.

A screening method is described to select monoclonal antibodies (Mabs) that bind to ocular melanoma-associated antigens (MAAs) retained in formalin-fixed, paraffin-embedded tissue sections. Small sections of epithelioid or spindle-cell-type uveal melanomas were cut into 2 mm cubes and reembedded in one block. Microslides were cut from this block and used to screen hybridoma supernatant fluid.

Retinal S antigen and retinoblastoma. A monoclonal antibody histopathologic study.

Using monoclonal antibody MAbA9-C6, which defines an epitope of retinal S antigen retained in fixed-tissue sections, we investigated S-antigen immunoreactivity in human fetal eyes from different gestational periods and 19 cases of retinoblastoma. S-antigen immunoreactivity was first observed in the outermost portion of the neuroblastic cell layer in the retina of a human fetus at 18 weeks' gestation, a stage preceding photoreceptor differentiation, and at all later stages examined thereafter. All adult eyes containing normal photoreceptors bound MAbA9-C6.

An antimelanoma monoclonal antibody and the histopathology of uveal melanomas.

Monoclonal antibody ME491 identifies a cutaneous melanoma-associated antigen in formaldehyde-fixed, paraffin-embedded tissues. This antibody was applied to tissue sections from 79 cases of formaldehyde-fixed, paraffin-embedded uveal melanomas. Sixty-nine (87.

Malignant melanoma of the choroid in a husband and wife.

A 52-year-old man was diagnosed as having a large malignant melanoma of the choroid in the right eye. Six years later his 58-year-old wife of almost 40 years was diagnosed as having a large malignant melanoma of the choroid in her left eye. In both patients the diagnosis was confirmed histologically following enucleation.

Subretinal cellular bands.

Subretinal cellular proliferation manifests itself in such a way that, with newer techniques in microsurgery, this previously often untreatable condition can be managed. Study of the ultrastructural components of the band suggests that it originates from pigment epithelium.