Comparison of Corneal Endothelial Cell Loss in Femtosecond Laser-assisted Cataract Surgery: Impact on Endothelial Cells in Different Regions.

PURPOSE: To compare changes in corneal endothelial parameters following femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification (CPS) in different corneal regions. SETTING: Chang Gung Memorial Hospital, Linkou, Taiwan, 2018- 2022. DESIGN: Single-center, retrospective. METHODS: Before and 1, 3, and 6 months post-op, specular microscopy was performed to measure endothelial cell density (ECD), corneal thickness, hexagonal cell rate (Hex), and coefficient of variation (CoV). Position 1 referred to the central cornea, Position 2 was nearest to the main wound, and Position 3 was at the peripheral zone diagonal to the main wound. RESULTS: This study analyzed 96 eyes in the FLACS group and 110 eyes in the CPS group. Preoperatively, Position 1 had lower ECD and CoV and higher Hex compared to the peripheral regions. FLACS patients had a significantly less phaco time and cumulative dissipated energy. At one month, FLACS patients showed a significantly smaller increase in corneal thickness at Positions 1 and 2. At 3 months, FLACS patients had lower endothelial cell loss (ECL) at Positions 1 and 3. ECL remained lower in FLACS patients at 6 months. The highest ECL was observed at Position 2 in both groups and was progressive up to 6 months. CONCLUSIONS: Following phacoemulcification, ECL varied in different corneal regions. At 3 months, the FLACS group exhibited significantly less ECL at the central cornea; however, the continued ECL at 6 months near the main wound suggested ongoing endothelial remodeling in the region.

Ocular Manifestations and Outcomes in Children With Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: A Comparison With Adult Patients.

PURPOSE: To compare the clinical features and visual outcomes in children and adults with Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). DESIGN: Retrospective comparative case series. METHODS: This retrospective study included 280 eyes of 140 patients (35 children and 105 adults) with SJS/TEN treated between 2010 and 2020. The primary outcome measures were the final best-corrected visual acuity (BCVA) and severity of dry eye. The secondary outcome measure was the medical and surgical therapies used. RESULTS: Among 64 eyes of children recruited in the study, acute ocular involvement was found in 58 eyes (90.6%). The chronic score in pediatric patients was significantly higher than that in adult patients (P = .004). The use of antibiotics/nonsteroidal anti-inflammatory drugs (NSAIDs) and Mycoplasma infection were the more common etiologies in children. In all, 75% of eyes in children maintained a visual acuity of 20/40 or better at a mean follow-up time of 4.3 years. The severity of dryness was comparable between the child and adult groups. The proportion of eyes undergoing amniotic membrane and oral mucosa transplantation was significantly higher in children than in adults in the chronic stage, reflecting that children exhibit much more severe complications. CONCLUSIONS: Although pediatric SJS/TEN patients have more severe ocular complications than adults, most children maintain long-term good vision. Early intervention and aggressive treatment help to preserve vision.

Integrin-mediated inhibition of interleukin-8 secretion from human neutrophils by collagen type I.

The function of neutrophils in the inflammatory response is modulated by contact with ECM proteins. We have now investigated the effect of collagen type I on secretion of the cytokine IL-8 by human neutrophils in vitro. Collagen type I inhibited the secretion of IL-8 from neutrophils maintained under basal conditions or stimulated with fMLF. This effect was accompanied by down-regulation of IL-8 mRNA, and it appeared to be specific to collagen type I among ECM proteins, in that it was not observed with fibronectin or laminin. The inhibitory effect of collagen type I on IL-8 secretion was dependent on collagen concentration and cell density. It was also abolished in the presence of antibodies to integrin alpha2beta1 but was not affected by antibodies to integrin alpha5beta1 or beta4. Our results thus suggest that collagen type I inhibits the secretion of IL-8 by human neutrophils in a selective manner and that this effect is mediated by the interaction of collagen with integrin alpha2beta1.

Up-regulation of HSP70 by the fibronectin-derived peptide PHSRN in human corneal epithelial cells.

HSP70 is a member of the heat shock protein family and is induced by various types of cellular stress. We examined whether HSP70 might play a role in the healing of corneal epithelial wounds. Given that the PHSRN peptide, which corresponds to the second cell-binding domain of fibronectin, promotes corneal epithelial migration, we investigated the effect of this peptide on HSP70 expression in cultured human corneal epithelial cells. Reverse transcription-polymerase chain reaction and immunoblot analyses revealed that PHSRN increased the amounts of HSP70 mRNA and protein in these cells in a concentration- and time-dependent manner, whereas a control peptide (NRSHP) had no such effects. Furthermore, the PHSRN-induced up-regulation of HSP70 was blocked by SB203580, an inhibitor of p38 mitogen-activated protein kinase (MAPK), but it was not affected by PD98059 or SP600125, inhibitors of signaling by the MAPKs ERK and JNK, respectively. Our results suggest that induction of HSP70 expression may contribute to the promotion of corneal epithelial migration by PHSRN and hence to corneal epithelial wound healing.