Cornea最新文献

Purpose: A detailed study of the physicochemical properties of SMILE-derived lenticules and evaluation of their drug delivery after loading with silver nanoparticles (AgNPs).

Methods: The lenticules were decellularized and modified with crosslinking concentrations of 0.01 (0.01E/L), 0.05 (0.05E/L), and 0.25 (0.25E/L) mmol N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide (EDC) per mg lenticule at 5:1 carbodiimide/N-hydroxysuccinimide (EDC/NHS) ratios. The degree of swelling, light transmittance, biomechanical properties, and stability of the non-crosslinked decellularized lenticules (DLs), 0.01E/L, 0.05E/L, and 0.25E/L were measured and characterized using Fourier transform infrared spectroscopy and transmission electron microscopy with non-crosslinked non-decellularized lenticules as controls. DLs, 0.01E/L, 0.05E/L, and 0.25E/L were soaked in AgNPs for 24 hours, and the concentration of the drug released was measured.

Results: There was no significant difference in the degree of swelling between the groups (P > 0.05). The light transmittance of the lenticules did not change after decellularization and crosslinking and decreased after loading with AgNPs. Non-decellularized lenticules biodegraded within 108 to 120 hours, and the other groups biodegraded within 96 to 108 hours in vitro. The 0.01E/L had the highest tensile strength. The absorption peak intensity ratio of the amide I band and the amide II band decreased, and the arrangement of collagen fibers was more compact in crosslinked decellularized lenticules. The 0.01E/L had the highest cumulative drug release (3.4 ± 0.91 μg).

Conclusions: Crosslinking decellularization improved the biomechanical properties and resistance to water absorption of lenticules, increased covalent bonds between collagen fibers, and improved drug delivery. Crosslinked decellularized lenticules can be used as a new corneal patch material and drug delivery carrier for drug AgNPs.

Purpose: To report the surgical management and outcomes of a patient with granulomatous inflammation following scleral tattooing, emphasizing the associated risks and clinical implications.

Methods: A 26-year-old woman with a history of multiple body modifications, including scleral tattooing, presented with bilateral ocular pain and discomfort. Clinical examination revealed corneal dellen and subconjunctival granulomas. The patient underwent surgical excision of the granulomas, with efforts to preserve the black conjunctival pigmentation. Histopathological analysis was performed on the excised tissue. The patient's visual acuity and ocular condition were monitored for 12 months postoperatively.

Results: Preoperative best-corrected visual acuity was 20/50 in the right eye and 20/60 in the left. Surgical excision of the granulomas was successfully performed, resulting in symptomatic relief and preservation of the black scleral coloration. Histopathological analysis confirmed the presence of exogenous pigment without hemosiderin or melanin deposits. Twelve months after surgery, the patient maintained a best-corrected visual acuity of 20/20 in both eyes, with no recurrence of granulomas or additional complications.

Conclusions: This case highlights the serious risks associated with scleral tattooing, including granulomatous reactions and corneal complications. Surgical intervention effectively addressed the ocular issues while preserving the desired cosmetic outcome. Greater public awareness and stronger regulations are critical to prevent such complications, and to prepare ophthalmologists for managing cases of scleral tattooing-related injuries.

Purpose: To report a case of herpes simplex virus (HSV) endotheliitis inducing acute interface fluid syndrome in a patient with a remote history of laser in situ keratomileusis (LASIK).

Methods: Case report and literature review.

Results: A 51-year-old man with a history of LASIK 16 years prior presented with unilateral HSV endotheliitis and was found to have acute interface fluid syndrome secondary to endothelial decompensation. The patient was treated with oral valacyclovir 1 g 3 times daily, prednisolone acetate 1% drops 4 times daily, timolol maleate 0.5% drops twice daily, topical 5% sodium chloride hypertonic ophthalmic solution drops 4 times daily, and 5% sodium chloride hypertonic ophthalmic ointment nightly. At 1-month follow-up, the patient had full resolution of the interface fluid and returned to baseline visual acuity.

Conclusions: This case underscores the importance of considering viral etiologies, such as HSV endotheliitis, in interface fluid syndrome beyond a decade after LASIK.

Purpose: To analyze the clinical outcome of organ-cultured endothelium-outward preloaded DMEK (pDMEK) using the RAPID cartridge.

Methods: This prospective study included 80 eyes of 80 patients who received a pDMEK. Best-corrected visual acuity (BCVA), endothelial cell count (ECC), and central corneal thickness were measured preoperatively and 4 to 6 weeks, 3 months, 6 months, and 1 year postoperatively. The difficulty of graft preparation and implantation, rebubbling, and re-DMEK frequency were evaluated.

Results: The graft preparation time was 5.3 ± 1.2 minutes on average. After preparation, the ECC before preloading was 2652 ± 180 cells/mm2 (P = 0.9, endothelial cell loss [ECL] = 0.8%). After pDMEK, the cornea started to clear up after 1.6 ± 1 day. Compared with the preoperative values, BCVA and central corneal thickness significantly improved during the postoperative course (P < 0.0001). At the first follow-up examination, the ECL was 43% (P < 0.0001) and remained stable throughout the follow-up period (all P > 0.5). Rebubbling was necessary in 39/80 patients (48.75%). One patient (1/80, 1.25%) required a re-DMEK after 1 year owing to secondary graft failure with insufficient ECC.

Conclusions: The clinical results after endothelium-outward pDMEK showed a significant improvement in BCVA and corneal thickness over the 1-year follow-up period, but the relatively high rebubbling rate and ECL should be taken into account. Therefore, we recommend that further comparative clinical studies should be conducted.

Purpose: To investigate the effectiveness of mitochondrial-targeted antioxidant mitoquinone (MitoQ) and nontargeted antioxidant idebenone (Idb) in alleviating mitochondrial dysfunction in corneal endothelial cells (CEnCs).

Methods: In vitro experiments were conducted using immortalized normal human corneal endothelial cells (HCEnC-21T; SVN1-67F) and Fuchs endothelial corneal dystrophy (FECD) cells (SVF5-54F; SVF3-76M). Cells were pretreated with MitoQ or Idb and then exposed to menadione (MN) with simultaneous antioxidant treatment. Mitochondrial parameters were evaluated through adenosine triphosphate viability assays, JC-1 staining for mitochondrial membrane potential, and Tom-20 antibody staining for fragmentation, with analysis performed using ImageJ software. HCEnC-21T cells were additionally exposed to ultraviolet-A (25 J/cm2) to assess drug effects under physiological stress. Mitochondrial fragmentation in FECD specimens was analyzed pre- and post-treatment with the drugs. Statistical analysis was conducted using 1-/2-way analysis of variance with post-hoc Tukey test.

Results: MitoQ and Idb enhanced cell viability and mitochondrial membrane potential in both normal and FECD cells under MN-induced stress. Idb reduced MN-induced mitochondrial fragmentation by 32% more than MitoQ in HCEnC-21T cells and by 13% more in SVF5-54F cells. Under ultraviolet-A stress, Idb and MitoQ improved mitochondrial function by 31% and 25%, respectively, with MitoQ increasing mitochondrial function by 42% in FECD specimens.

Conclusions: Differential responses in mitochondrial dysfunction across cell lines highlight disease heterogeneity. MitoQ and Idb protected CEnCs from oxidative stress and improved mitochondrial bioenergetics, suggesting that mitochondrial-targeted antioxidants could be considered for mitochondrial dysfunction in CEnCs.

Purpose: This study aimed to describe a novel technique of direct anterior chamber (AC) air replacement (DACAR) for the management of Descemet stripping automated endothelial keratoplasty (DSAEK) in postvitrectomized eyes and eyes with previous glaucoma surgery.

Methods: DACAR was performed after a corneal donor graft was transplanted through a wound using the pull-through technique. DACAR involves stabilizing the graft with forceps while introducing air into the AC via an infusion cannula to ensure complete air exchange. The air was maintained in the AC at all times using a vitrectomy machine. The air pressure was maintained at 30 mm Hg for 15 minutes.

Results: The DACAR technique was performed in 34 patients, and conventional pull-through technique DSAEK was performed in 32 high-risk patients. The DACAR group had shorter DSAEK surgical procedures (P = 0.009) and a lower incidence of corneal graft detachment in the early postoperative period (P < 0.001) than the conventional DSAEK group.

Conclusions: DACAR is performed in patients having previously undergone vitrectomy or glaucoma surgery to prevent corneal graft detachment during the early postoperative period and to reduce the length of surgery.

Purpose: This study aims to evaluate the repeatability of posterior corneal surface and Zernike polynomial measurements of 2 different ocular biometers and Scheimpflug devices in keratoconus (KC) and healthy eyes.

Methods: This is a prospective, comparative study performed at the Department of Ophthalmology, Goethe-University Frankfurt, Germany. Included were KC and healthy eyes. Two consecutive measurements of 1 eye per patient, taken with Galilei G6 (Ziemer, Switzerland) and Pentacam AXL (Oculus, Germany), were analyzed. Repeatability was evaluated for posterior keratometry (K1, K2 and Km), posterior astigmatism, and the following Zernike polynomials: Defocus, Astigmatism, Coma, Trefoil, Spherical Aberration, and root mean square (RMS) total.

Results: Both devices showed good repeatability for many of the analyzed parameters with several interclass correlation (ICC) values of 0.96 or above. Regarding the Zernike polynomials, ICC values and the narrowness of the 95% limits of agreement varied in between the devices for each polynomial. In addition, the agreement between both devices was reduced for the Zernike analysis. The only comparable polynomials were Spherical Aberration with a high interdevice ICC of 0.955 and RMS total with a lower ICC of 0.591 (both in the KC group).

Conclusions: Regarding the posterior measurements, Pentacam AXL showed higher repeatability in healthy eyes and Galilei G6 in KC eyes. For both devices, the intradevice repeatability was high for most Zernike polynomials. However, the interdevice comparability for Zernike polynomials was reduced to Spherical Aberration and RMS total, with Spherical Aberration showing higher agreement in KC eyes.

Purpose: To evaluate the effect of subconjunctival injection of dexpanthenol on corneal neovascularization and inflammation in rats with induced chemical burns.

Methods: This experimental study included 40 female albino Wistar rats. Chemical burns were induced in the right eye of all rats on the first day, and the left eye was used as a control. Rats were randomly divided into 5 groups. The no-treatment group (group 1) received no injections. Balanced salt solution injection in the sham group (group 2), dexpanthenol injection in the dexpanthenol group (group 3), bevacizumab injection in the bevacizumab group (group 4), and combined dexpanthenol and bevacizumab injection in the combined group (group 5) were administered subconjunctivally on day 7. The right corneas of all rats were photographed on days 7 and 14 to evaluate corneal neovascularization. The 2 corneal images were compared, and the differences were analyzed. All rats were euthanized, and the corneas were isolated. The levels of tumor necrosis factor-alpha (TNF-α), vascular endothelial growth factor-A, malondialdehyde (MDA), apoptosis, reduced glutathione (GSH), and total oxidant status were measured in rat corneas.

Results: Dexpanthenol reduced corneal neovascularization, and the difference was significant compared with the no-treatment and sham groups (P < 0.05). No significant difference in corneal neovascularization was observed between the dexpanthenol and bevacizumab groups. Dexpanthenol had a significant positive effect on vascular endothelial growth factor-A, TNF-α, total oxidant status, MDA, and GSH levels compared with the sham group (P < 0.05).

Conclusions: Dexpanthenol may help control corneal neovascularization and inflammation after chemical burns.