Biomedical subjects

T F Essman

Publications and source records attributed to T F Essman.

3 recordsLinked to original sources

PubMed1997

Treatment outcomes in a 10-year study of endogenous fungal endophthalmitis.

BACKGROUND AND OBJECTIVE: To review prevalence of organisms, associated factors, and treatment outcomes from one medical center's 10-year experience managing culture-proven endogenous fungal endophthalmitis (EFE). PATIENTS AND METHODS: The authors retrospectively reviewed the microbiology and corresponding clinical records of patients diagnosed as having culture-proven EFE at the Bascom Palmer Eye Institute during a 10-year period. RESULTS: Culture-proven EFE occurred in 20 eyes of 18 patients. Candida species occurred in 17 of 20 eyes (85%), and Aspergillus species occurred in 3 of 20 eyes (15%). The most common association was long-term intravenous line placement, which was present in 12 patients (67%). Whereas 12 patients (67%) had a history of recent hospitalization, only 2 (11%) had a documented history of systemic fungal infection. After initial examination, only 2 patients had a systemic culture positive for a fungal organism (none had a positive blood culture). Treatment after initial examination included pars plana vitrectomy in 17 of the 20 eyes (85%), intravitreal amphotericin B in 19 eyes (95%), and systemic antifungal medication in 16 eyes of 15 patients. Thirteen of the 17 eyes (76%) with Candida endophthalmitis and 0 of 3 eyes with Aspergillus endophthalmitis achieved visual acuity of 20/400 or better. CONCLUSION: The most common cause of culture-proven EFE at the authors' institution is Candida species. The overall visual outcomes were more favorable for Candida cases than they were for Aspergillus cases. In the treatment of patients with marked vitreous infiltrates from EFE, pars plana vitrectomy, intravitreal amphotericin B injection, and administration of appropriate systemic antifungal medication (fluconazole for Candida) are generally recommended.

Adult↗

PubMed1994

Selective regeneration of photoreceptors in goldfish retina.

Previous work has shown that the neural retina in adult goldfish can regenerate. Following retinal damage elicited by surgical or cytotoxic lesions, missing neurons are replaced by foci of proliferating neuroepithelial cells, which previous studies have suggested are derived from rod precursors. In the intact retina, rod precursors proliferate but produce only new rods. The regenerative responses observed previously have involved replacement of neurons in all retinal layers; selective regeneration of specific neuronal types (except for rod photoreceptors) has not been reported. In the experiments described here, we specifically destroyed either cones alone or cones and rods with an argon laser, and we found that both types of photoreceptors regenerated within a few weeks. The amount of cone regeneration varied in proportion to the degree of rod loss. This is the first demonstration of selective regeneration of a specific class of neuron (i.e., cones) in a region of central nervous tissue where developmental production of that class of neuron has ceased. Selective regeneration may be limited to photoreceptors, however, because when dopaminergic neurons in the inner retina were ablated with intraocular injections of 6-hydroxydopamine, in combination with laser lesions that destroyed photoreceptors, the dopaminergic neurons did not regenerate, but the photoreceptors did. These data support previous studies which showed that substantial cell loss is required to trigger regeneration of inner retinal neurons, including dopaminergic neurons. New observations here bring into question the presumption that rod precursors are the only source of neuronal progenitors during the regenerative response. Finally, a model is presented which suggests a possible mechanism for regulating the phenotypic fate of retinal progenitor cells during retinal regeneration.

Animals↗

PubMed1992

Screening for pediatric eye disease.

The majority of preschool children in the United States are not screened for visual problems. To avoid permanent visual loss, standardized screening should be incorporated into well-child examinations so that treatment can be initiated promptly. Newborns should be checked for the red reflex, pupillary responses and any constant eye deviation. Infants six months old should be checked for these responses and for "fixation and following" and ocular alignment. Visual acuity should be tested in three- to four-year-old children using the "tumbling E" test, Allen pictures or the HOTV chart.

Blinking↗