Biomedical subjects

Myrna S Santos

Publications and source records attributed to Myrna S Santos.

3 recordsLinked to original sources

PubMed2005

Survival analysis of conjunctival limbal grafts and amniotic membrane transplantation in eyes with total limbal stem cell deficiency.

PURPOSE: To evaluate the survival of conjunctival limbal grafts and amniotic membrane transplantation (AMT) for total limbal stem cell deficiency (LSCD) and the influence of several parameters as cause of LSCD, dry eye, keratinization, eyelid abnormalities, HLA compatibility, systemic immunosuppression, and keratoplasty (PKP) on surgical outcome. DESIGN: Prospective, noncomparative, interventional case series. METHODS: Thirty-three eyes of 31 patients with total LSCD that underwent conjunctival limbal grafts and AMT at the Department of Ophthalmology, Federal University of São Paulo were included in this study. Cumulative graft survival as well as the influence of several variables on surgical outcome was analyzed. RESULTS: Ten eyes (30%) underwent conjunctival limbal autograft and 23 (70%) underwent conjunctival limbal allograft from living HLA-matched donor. Graft survival was seen in 13 eyes (40%) at 1 year and in 11 eyes (33.3%) at 2 years, with a cumulative survival of 33% after a mean follow-up time of 33 months. Increase in postoperative visual acuity was observed in 20 eyes (60.6%) during this period. Marked impact on graft survival was observed for patients with Stevens-Johnson syndrome, dry eye, keratinization, eyelid abnormalities, and allogeneic conjunctival limbal transplantation (independently of HLA compatibility) (P < .05). Preoperative dry eye was the most important prognostic parameter for surgical outcome (P < .001). CONCLUSIONS: Conjunctival limbal grafts associated with AMT are useful for restoring corneal epithelium phenotype in eyes with total LSCD. However, the cumulative survival declines substantially over a 2-year period. Considering all investigated variables, dry eye was the most important prognostic parameter.

Adult↗

PubMed2005

Amniotic membrane use in ophthalmology.

PURPOSE OF REVIEW: The purpose of this review is to describe the most recent and relevant clinical and experimental data about the use of amniotic membrane in ophthalmology. RECENT FINDINGS: The amniotic membrane is a biologic tissue that has been used as a graft for corneal and conjunctival reconstruction in a variety of ocular surface diseases. It is avascular and possesses anti-angiogenetic, anti-scarring and antiinflammatory properties. It is not a substitute but rather a substrate upon which cells can migrate and regenerate, forming new and healthy tissue. The amniotic membrane can also be used as a biologic patch, as a bandage, to treat acute inflammatory disorders. With the development of cell therapy, amniotic membrane can be also used as a carrier of limbal stem cells or their progeny, cultivated in vitro. SUMMARY: Amniotic membrane use in ophthalmic surgery has been shown to provide an alternative for corneal and conjunctival reconstruction in many clinically challenging situations; however, there is still a lack of scientific evidence based on randomized comparative studies to prove that its use is better than other alternative therapies for ocular surface reconstruction.

Amnion↗

PubMed2003

Amniotic membrane with living related corneal limbal/conjunctival allograft for ocular surface reconstruction in Stevens-Johnson syndrome.

OBJECTIVE: To report the use of preserved amniotic membrane and living related corneal limbal/conjunctival transplantation in total limbal stem cell and conjunctival deficiency secondary to severe Stevens-Johnson syndrome. DESIGN: Prospective, noncomparative, interventional case series. PATIENTS AND METHODS: Ten eyes of 10 patients with total limbal stem cell and conjunctival deficiency secondary to Stevens-Johnson syndrome underwent excision of cicatricial tissue followed by amniotic membrane and living related corneal limbal/conjunctival transplantation. MAIN OUTCOME MEASURES: Reconstruction of corneal epithelium (clear appearance without epithelial defect, normal fluorescein permeability, and the absence of conjunctiva-derived goblet cells on impression cytologic testing), decrease in corneal vascularization, and improvement in visual acuity. RESULTS: During a mean follow-up of 16.7 months, satisfactory ocular surface reconstruction was obtained in 2 eyes (20%), with reduced inflammation and vascularization and a mean epithelialization time of 3 weeks. Surgical failure was observed in 4 cases (40%) and complications (infection) in 4 cases (40%). Visual acuity improved in 4 eyes (40%), remained stable in 5 eyes (50%), and decreased in 1 eye (10%). CONCLUSIONS: Amniotic membrane and living related corneal limbal/conjunctival transplantation were successful in 20% of severe cases of total limbal stem cell and conjunctival deficiency secondary to Stevens-Johnson syndrome. A high proportion of postoperative complications, in particular, infection, seemed to jeopardize a favorable outcome.

Adolescent↗