Acanthoamoeba Keratitis Induced by a Therapeutic, Soft Contact Lens: Diagnosis via Gram Staining

Purpose: We report two cases of Acanthamoeba keratitis diagnosed by Gram staining in patients who had recently worn therapeutic, soft contact lenses and had no history of lens use for visual correction.Case summary: The first patient was initially diagnosed with suspected mixed bacterial or fungal keratitis before a final diagnosis of Acanthamoeba keratitis was confirmed by Gram staining of a corneal smear. The second patient was initially diagnosed with a persistent epithelial defect caused by an earlier lid injury inflicted by a metallic foreign body, and then with a suspected mixed infection combined with herpetic uveitis. The patient was finally diagnosed with Acanthamoeba keratitis by Gram staining of a corneal smear. Both cases were treated with polyhexamethylene biguanide and chlorhexidine.Conclusions: Therapeutic, soft contact lenses are used to enhance corneal, epithelial wound healing in conjunction with antimicrobial prophylaxis. However, application of such a lens to a diseased cornea may predispose to the development of microbial keratitis caused by microorganisms resistant to the usual, prophylactic, antimicrobial eye drops. Therapeutic, soft contact lenses are associated with a risk of Acanthamoeba keratitis; early diagnosis is important. Gram staining of a corneal smear is useful in this context. Acanthamoeba is not eradicated by empirical broad-spectrum antimicrobials.

Femtosecond laser-assisted deep anterior lamellar keratoplasty: A safer option in keratoconus surgery

Purpose To evaluate postoperative safety of femtosecond laser deep anterior lamellar keratoplasty performed with an innovative anvil profile in keratoconus patients. Methods This is a single-center, retrospective cohort study. We reviewed medical records of 89 keratoconus patients that underwent femtosecond laser deep anterior lamellar keratoplasty surgery (46 eyes) and manual deep anterior lamellar keratoplasty (47 eyes). Inclusion criteria required: age > 18 years old, best-corrected visual acuity < 0.3 LogMAR, continuous suture of the graft, postoperative immunomodulant regimen with dexamethasone 0.1% for 6 months and at least 12 months follow-up. Previous eye surgery, hydrops, and other ocular disease were excluded. The main outcome measures were postoperative events: rejections, persistent epithelial defects, and graft failures. Results During the follow-up (20 ± 6 months) graft rejection was diagnosed in 0 of femtosecond laser deep anterior lamellar keratoplasty versus 6 (17%) of manual deep anterior lamellar keratoplasty [ p 0.027], persistent epithelial defect in 0 of femtosecond laser deep anterior lamellar keratoplasty versus in 4 (11%) of manual deep anterior lamellar keratoplasty [ p 0.048] and graft failure occurred in 4 (11%) of manual deep anterior lamellar keratoplasty. The best-corrected visual acuity, after removal of sutures, was better in the femtosecond laser deep anterior lamellar keratoplasty group 0.09 ± 0.08 LogMAR versus 0.16 ± 0.13 LogMAR in manual deep anterior lamellar keratoplasty [ p 0.035] group although refractive spherical equivalent and cylinder, topographic average keratometry and cylinder were similar. Conclusions Anvil-shaped femtosecond laser deep anterior lamellar keratoplasty in keratoconus surgery increases safety and readiness of recovery, decreasing the incidence of corneal rejection, epithelial defects, graft failures, and producing better best-corrected visual acuity after removal of sutures.

Maternal finger-prick allogenic blood for persistent corneal epithelial defects

This is a case of a 17-year-old patient with aniridia-related keratopathy and persistent epithelial defect (PED) treated successfully using maternal finger-prick blood (FPB). Maternal allogenic FPB treatment was initiated to the patient who was non-compliant with the use of autologous FPB. The PED was successfully managed with maternal FPB treatment with rapid and complete closure of the epithelial defect. Additionally, there was immediate and sustained symptomatic improvement to pain and recovery of vision in the only seeing eye. There was no immunological reaction to allogenic blood. Maternal finger-prick allogenic blood could serve as a potential alternative to serum eye drops or autologous FPB in the management of refractory PED, particularly in reference to the paediatric or the vulnerable age group. Further studies are required to confirm the role of allogenic blood in the treatment of PED.

Ocular surface characteristics and colonization in a burn center: A prospective cohort study

We aimed to evaluate the characteristics and colonization by pathogenic microorganisms of the ocular surface in patients in a burn center and to determine their association with sedation, mechanical ventilation, and periocular burn. We prospectively evaluated 40 patients during an eight-month period. Five evaluations where performed, at baseline and weekly on four more occasions or until hospital discharge or death. On each visit, we assessed periocular burn, lid position, Bell’s phenomenon, Schirmer’s test, presence of chemosis, conjunctival hyperemia, and exposure keratopathy; conjunctival fornix swabs were taken for microbiology culture. Also, we documented the level of sedation, mechanical ventilation status, and systemic and ocular treatment. Absent Bell’s phenomenon and chemosis were significantly different at baseline in patients under mechanical ventilation, sedation, and in those with periocular burn. The cumulative incidence of exposure keratopathy was 22.5% and the cumulative incidence of ocular surface colonization by pathogenic microorganisms was 32.5%. Both outcomes were associated with mechanical ventilation and periocular burn. The most frequent pathogenic microorganisms in the ocular surface were Candida parapsilosis, Acinetobacter baumanii, and Pseudomonas aeuroginosa. We did not observe any case of persistent epithelial defect, infectious keratitis, corneal perforation or corneal opacity in this cohort. Results from our study may benefit future patients by allowing better risk stratification and treatment strategies for the ocular surface care in burn units.

Safety and efficacy of repeated crosslinking assisted by transepithelial double-cycle iontophoresis in keratoconus progression after primary corneal crosslinking

Objectives To evaluate the safety and efficacy of repeated corneal collagen crosslinking assisted by transepithelial double-cycle iontophoresis (DI-CXL) in the management of keratoconus progression after primary CXL. Methods A retrospective analysis was conducted in the patients who underwent repeated CXL between 2016 and 2018. These patients were treated with DI-CXL if keratoconus progression was confirmed after primary CXL. Scoring of ocular pain and corneal epithelial damage, visual acuity, corneal tomography, in vivo corneal confocal microscopy (IVCM) was performed before and at 3, 6, 12, and 24 months after DI-CXL. Results Overall, 21 eyes of 12 patients (mean age 17.3 ± 1.9 years) were included in this study. Before DI-CXL, an average increase of 4.26 D in Kmax was detected in these patients with a mean follow-up interval of (23.0 ± 13.7) months. After DI-CXL, corneal epithelial damage rapidly recovered within days. Visual acuity remained unchanged with follow-up of 24 months. When compared to baseline, significant decreases were observed in Kmax (at 3 months) and K2 (at 3 and 6 months) after DI-CXL. Corneal thickness of thinnest point significantly decreased at 3 months postoperatively. When compared to baseline, no significant differences were found in any of the refractive or tomographic parameters at 12 and 24 months. IVCM revealed trabecular patterned hyperdense tissues after DI-CXL in the anterior stroma at the depth of 200 μm or more. No corneal infiltration or persistent epithelial defect was recorded after DI-CXL. Conclusion DI-CXL is safe and effective as a good alternative in stabilizing keratoconus progression after primary CXL.

Post-operative complications of penetrating corneal keratoplasty in patients with anterior segment toxic syndrome secondary to cataract surgery

Introduction: Toxic Anterior Segment Syndrome (TASS) after cataract surgery may cause severe corneal decompensation that compromises corneal transparency and may require penetrating corneal keratoplasty to improve visual acuity. Objective: We evaluated the postoperative complications of patients who underwent penetrating corneal transplantation for severe corneal decompensation secondary to TASS after cataract surgery, such as persistent epithelial defect, glaucoma, and primary and secondary transplant button failure. We will also evaluate pre- and postoperative visual acuity, graft survival time, and the presence of anterior chamber disorganization. Methods: Retrospective observational study in which a review of medical records of 9 patients diagnosed with TASS after cataract surgery who underwent penetrating corneal keratoplasty will occur. Results: In the present study all operated patients had glaucoma after penetrating corneal transplantation, and this presence of glaucoma was not correlated with graft survival time and with any other parameter evaluated. The presence of persistent epithelial defect correlated negatively with visual acuity. Conclusion: Postoperative complications of penetrating corneal transplantation in patients with TASS were frequent, such as glaucoma, primary and secondary button failure and persistent epithelial defect. The only complication that compromised visual acuity was the persistent epithelial defect. All patients evolved with glaucoma.

Clinical forms of allergic eye manifestations: prospects of therapy

The review presents the main clinical forms of eye allergy. The modern classification of conjunctival allergic diseases (CAD) divides them into several types according to the presence or absence of proliferative changes complicated by atopic dermatitis or mechanical artifactual irritation. These include: 1) allergic conjunctivitis (AC) without proliferative changes, including seasonal allergic conjunctivitis and chronic allergic conjunctivitis, in which the symptoms persist the whole year; 2) atopic keratoconjunctivitis, a chronic allergic conjunctival disease affecting patients with atopic dermatitis, 3) spring keratoconjunctivitis with conjunctival and proliferative changes — papillary conjunctival hyperplasia with the involvement of the cornea (superficial punctate keratitis, erosion, persistent epithelial defect, sterile corneal ulceration), 4) giant papillary conjunctivitis (GPC) accompanied by proliferative changes in the upper lid and the arch of the conjunctiva of the eyeball, caused by mechanical irritation factors (contact lenses, eye prostheses, or surgical sutures). To treat these conditions, the following groups of medications are used: artificial tears; topical antihistamine drugs; mast cell membrane stabilizers; dualaction drugs, preferably without preservatives, nonsteroid anti-inflammatory medications and vasoconstrictors having side effects. Olopatadin 1 mg/1 ml, preservative free (Olofadin -ECO), has certain advantages due to the fact that it combines antihistamine and membrane stabilizing action. Due to the presence of an antihistamine component in the composition, an acute reaction is stopped, while the effect of the drug is accumulated due to the presence of a membrane-stabilizing component. It is safe for long-term therapy.