Biomedical subjects

R Y Foos

Publications and source records attributed to R Y Foos.

At least 109 records · Page 6Linked to original sources

PubMed1977

Vitreoretinal juncture; epiretinal membranes and vitreous.

This report reviews current knowledge of the ultrastructural features of the vitreoretinal juncture in its normal state, in eyes with posterior vitreous detachment (PVD), and in eyes with epiretinal membranes (ERM's) and then presents new concepts concerning the interrelationship of ERM's and the vitreous. Results show no vitreous residues on retinal surface following uncomplicated rhegmatogenous (senescent) PVD. In eyes that develop ERM's before vitreous detachment, however, a layer of vitreous may be entrapped beneath the ERM and on adjacent membrane-free retina when PVD ocurs. ERM's may be a cause as well as an effect of PVD.

Aging↗

PubMed1977

Incisional complications in pars plana vitrectomy.

Four cases of incisional complications following pars plana vitrectomy are presented. In each instance, excessive fibrosis occurred at the wound site. In one patient, the disorder was mild and did not lead to clinical difficulties during his lifetime, however, in the three severe cases the eyes were lost secondary to intraocular organization and phthisis bulbi. Possible contributing factors include diabetes mellitus, excessive trauma and necrosis at the wound site, postoperative inflammation, and vitreous involvement in the wound. Since no treatment is known, atraumatic management of the incision using microsurgical techniques is strongly recommended.

Adult↗

PubMed1976

Regional ischemic infarcts of the retina.

Macroscopic and light microscopic features of regional ischemic infarcts of retina in autopsy eyes are described. Lesions were found throughout life span, most patients having significant primary or secondary vascular disease (younger had systemic hypertension, rheumatic heart disease, vasculitis or sickle hemoglobinopathy; most older patients had arteriosclerosis). Diabetes mellitus and infarction of other organs (including brain) also were common. Topographically almost all lesions were found in posterior fundus; most were temporal and involved anatomical macula. Microscopically there was destruction of inner retinal layers with preservation of outermost cells of inner nuclear layer; occasionally ganglion cell layer was relatively spared.

Adolescent↗

PubMed1975

Vitreoretinal juncture; healing of experimental wounds.

Healing of mechanically-induced, minimal wounds of vitreoretinal juncture in non-vascularized retina of rabbits was studied with electron microscopy at 1 and 3 days, and 1, 2, 6 and 10 weeks. Neuroectodermal scar was formed by two processes, each having a specific anatomical relationship to wound. Accessory gliocytosis, in which accessory glia adjacent to wound become phagocytic and proliferate; following this their progeny migrate to wound and progressively differentiate into fibrous astrocytes to fill in the wound proper. Plexiform gliosis, in which the Müller cell side branches proliferate to form a layer about the perimeter of wound. The retinal inner limiting lamina did not regenerate. The significance of these findings in relation to epiretinal membrane formation in man is discussed.

Animals↗

PubMed1975

Ultrastructural features of posterior vitreous detachment.

The ultrastructural features of vitreoretinal relations in the posterior fundus of enucleated eyes were studied. Vitreous detachment occurs at the anatomical vitreoretinal juncture, between the inner limiting lamina of the retina and the vitreous cortex, the surface of the lamina becoming smooth and without vitreous residues.

Adult↗

PubMed1975

Acute retrolental fibroplasia.

A pathologic analysis of 19 cases of acute retrolental fibroplasia in autopsy eyes from paranatal infants is presented. The clinical profile of these subjects showed no clear-cut maternal factors. Infant factors included systemic congenital anomalies (14 cases); ocular congenital anomalies (1); birth weight--less than 1500 grams (12), more than 2000 grams (4); neonatal complications--"respiratory distress" (8), "apneic spells" (7), Erythroblastosis fetalis (3); oxygen therapy of varying amounts (14); periodic elevations of arterial oxygen (7); and varying survival times (intrauterine death, one case; less then 48 extrauterine hours, 9 cases). Considering all cases, the lesions showed a progressive pattern--beginning with proliferation of primitive vascular mesenchyme in vanguard of advancing vasculature (four cases), formation of intraretinal band of endothelial cells in rear guard (10 cases), and finally, extraretinal neovascularization from rear guard zone (five cases).

Acute Disease↗

PubMed1975

Experimental hematogenous endophthalmitis caused by Candida albicans.

For a rabbit model of hematogenous endophthalmitis caused by Candida, 80 New Zealand white rabbits were given intravenous injections of 10-5 Candida albicans. Two weeks after infection 88 percent of infected rabbits had ocular lesions with clinical appearance identical to that of human lesions. Cultures of the chorioretina and kidneys averaged 10-4.3 and 10-3.9 organisms per g of tissue, respectively, three days after infection and remained positive for 38 days. Ninety-five percent of rabbits with positive cultures of the chorioretina had positive cultures from other organs. The ocular lesions were focal chorioretinitis characterized by a combination of granulomatous and acute suppurative reactions. Hematogenous endophthalmitis caused by Candida in the rabbit is a useful model for study of the pathogenesis and treatment of the disease in humans.

Animals↗

PubMed1975

Tears of the peripheral retina; pathogenesis, incidence and classification in autopsy eyes.

A pathogenic analysis of full-thickness tears of the peripheral retina and their incidence in autopsy eyes is presented. Tears were classified according to their location (ora or postora, quadrant and zone), type of traction (zonuloretinal or vitreoretinal), morphological features (flap or operculum), presence or absence of posterior vitreous detachment, and their association with other ocular lesions. Tears were present in 2% of eyes. They were postoral in 92%, uniformly distributed in the quadrants, in the equatorial zone in 95%, related to vitreoretinal traction in 94%, of the flap type in 64%, accompanied by posterior vitreous detachment in 79% and were significantly more prevalent in eyes with lattice degeneration (17%). A simple classification of postoral tears is recommended which incorporates these pathogenic principles and includes three types according to their topographical relationship to the vitreous base: intrabasal--caused by avulsion of zonular traction tufts; juxtabasal--related to traction of the posteriorly detached vitreous on irregularities in posterior border of vitreous base; extrabasal--resulting from avulsion of cystic retinal tufts.

Adult↗

PubMed1974