Beauveria bassiana Keratitis: A Case Series and Review of Literature.

BACKGROUND: Beauveria bassiana is a filamentous fungus commonly used as an insecticide that rarely causes keratitis. METHODS: Patients affected by Beauveria bassiana keratitis were retrospectively recruited at San Raffaele Hospital (Milan, Italy) between 2020 and 2022. All subjects underwent comprehensive ophthalmic evaluation, including in vivo confocal microscopy (IVCM) and microbiologic examination of corneal scrapings. Beauveria bassiana was identified using 18S rDNA targeted PCR. RESULTS: Four eyes of four patients (51 ± 8.8 years old) were evaluated. The main risk factors were soft contact lens wear (75%) and trauma with vegetative matter (50%). A superficial infiltrate was displayed in the majority of patients. Three cases (75%) showed hyphae on IVCM. All patients showed clinical improvement after topical antifungal therapy, although mostly through a combination of two antifungals (75%). One patient with a deeper infection required a systemic antifungal agent after one month of topical therapy. All cases required debridement to reduce the microbial load and enhance drug penetration. All patients experienced keratitis resolution following medical treatment (average: 3.3 months). CONCLUSIONS: The identification of risk factors and the early diagnosis of Beauveria bassiana keratitis are fundamental in order to avoid its penetration in the deeper corneal stromal layers. Topical antifungal drugs, possibly accompanied by ulcer debridement, may be a successful treatment if instilled from the early phases of the disease.

Safety and Efficacy of Corneal Cross-Linking in Patients Affected by Keratoconus: Long-Term Results.

The present study evaluated the effectiveness and safety of corneal collagen cross-linking (CXL). A total of 886 eyes with progressive keratoconus were enrolled in a retrospective cohort study in a tertiary care university hospital. CXL was performed using a standard epithelium-off Dresden protocol. Visual outcomes, maximum keratometry (Kmax), demarcation line measurements, and complications were recorded. Visual outcomes and keratometric data were analyzed in a subgroup comprising 610 eyes. Uncorrected distance visual acuity (UDVA) improved from 0.49 ± 0.38 LogMAR to 0.47 ± 0.39 LogMAR (p = 0.03, n = 610) three years after the procedure, while corrected distance visual acuity (CDVA) improved from 0.15 ± 0.14 LogMAR to 0.14 ± 0.15 LogMAR (p = 0.007, n = 610). A significant reduction of Kmax from 56.28 ± 6.10 to 54.98 ± 6.19 (p < 0.001, n = 610) was observed three years after CXL. In five eyes (0.82%, 5/610) keratoconus progression continued after CXL. Three eyes were retreated successfully with documented refractive and topographic stability after five years. In the 35 eyes that completed 10 years of follow-up, mean visual acuity and topographic parameters remained stable. In conclusion, CXL is a safe and effective treatment for avoiding keratoconus progression. Long-term data are encouraging, supporting a high safety profile for this procedure.

Evaluation of a Post-Operative Therapy Protocol after Epithelium-Off Corneal Cross-Linking in Patients Affected by Keratoconus.

A large retrospective study evaluated the safety of a post-operative therapy protocol after epithelium-off corneal collagen cross-linking (CXL). In total, 1703 eyes of the 1190 patients with progressive keratoconus were enrolled in a retrospective cohort study in a tertiary care university hospital. CXL was performed using a standardized technique (Dresden protocol: 0.1% riboflavin solution containing dextran 20% for 30 min during the soaking phase followed by 30-min ultraviolet A irradiation (3 mW/cm2)). Postoperatively, a bandage contact lens was applied, and therapy included a topical fluoroquinolone antibiotic until the epithelium healed, followed by topical fluorometholone treatment for three weeks. Post-operative complications were recorded and analyzed. No cases of infectious keratitis occurred, whereas peripheral sterile infiltrates were observed in 1.17% of cases. Trace haze was typically present but did not have an impact on visual acuity. In fifteen cases (0.88%), visually significant anterior stromal opacity developed. Mild signs of dry eye were observed in 22 eyes (1.29%). The present study demonstrates that a post-operative treatment protocol including fluoroquinolone antibiotics and a BCL in the first phase until complete epithelial healing, followed by a three-week period of topical steroid treatment is safe and not associated with the development of microbial keratitis.

IOL Power Calculation in Eyes Undergoing Combined Descemet Membrane Endothelial Keratoplasty and Cataract Surgery.

PURPOSE: To assess the accuracy of different corneal powers for intraocular (IOL) power calculation in combined Descemet membrane endothelial keratoplasty (DMEK) and cataract surgery and investigate whether preoperative parameters correlate to the prediction error (PE). METHODS: This prospective case series involved patients with Fuchs endothelial dystrophy receiving combined DMEK and cataract surgery. Preoperatively, patients underwent optical biometry and anterior segment OCT (AS-OCT). AS-OCT measurements were repeated 6 months postoperatively, when final refraction was assessed. The PE was calculated using the preoperative average keratometry (Kave) measured by the optical biometer and User Group for Laser Interference Biometry (ULIB) constants. It was also calculated, after constant optimization, using the preoperative Kave from both devices and the total corneal power (TCP) measured by AS-OCT, as well as the postoperative Kave and TCP measured by AS-OCT. RESULTS: ULIB constants resulted in the highest hyperopic PE (P < .0001). Constant optimization improved the results, because the PE was zeroed out and the absolute PEs decreased. No significant difference was found among the Barrett Universal II, Emmetropia Verifying Optical 2.0, Haigis, Hoffer Q, Holladay 1, Kane, and SRK/T formulas. Further improvement was achieved with the postoperative Kave and TCP, although the accuracy remained moderate. The PE based on preoperative corneal measurements was correlated to the amount of corneal flattening; the latter could be predicted by multiple linear regression accounting for anterior and posterior corneal radii (P = .0002) and was correlated to the preoperative anterior/posterior ratio. CONCLUSIONS: Constant optimization is beneficial for combined DMEK and phacoemulsification. Predicting postoperative corneal flattening may improve the results of IOL power accuracy. [J Refract Surg. 2022;38(7):435-442.].

Two-step keratoplasty for deep vascularized corneal opacity with severe peripheral thinning following Acanthamoeba keratitis.

PURPOSE: In cases of corneal opacity with vascularization and peripheral thinning, traditional keratoplasty techniques have several risks and drawbacks. We report the results of a two-step surgical strategy consisting in performing a large diameter tectonic lamellar keratoplasty (TLK) to restore appropriate corneal thickness and an avascular recipient bed, followed by central optical PK within the lamellar graft at a later date. METHODS: This single-institution study analyzes the results of 7 eyes of 7 patients who received PK after large diameter TLK. All patients were affected by deep post-infectious corneal opacity with persistent stromal vascularization and peripheral thinning. The main outcomes measured were graft survival, visual acuity, refraction, and endothelial cell density. RESULTS: TLK was performed in all cases with 10/10.1-mm diameters. After a mean interval of 14 months, central PK was performed with a median host-graft diameter of 7.75/8.25 mm. Mean follow-up after PK was 52 months. At last follow-up, 6/7 (86%) grafts were clear. Endothelial rejection occurred in 5/7 (71%) eyes, with one patient having multiple episodes and subsequent graft failure. At 2 years, all patients had a visual acuity ≥ 20/40, with an average refractive astigmatism of 3.75 diopters. CONCLUSION: Optical PK within a previous TLK is a safe and efficient technique for treating deep corneal opacity associated with extensive vascularization and peripheral thinning. Extended follow-up period is necessary to assess endothelial cell loss and long-term efficacy of the procedure.

Corneal collagen cross-linking for management of keratoconus in patients affected by Tourette syndrome.

PURPOSE: To present a series of two patients affected by Tourette syndrome (TS) and progressive keratoconus. CASE SERIES: Two young male patients with keratoconus and TS were referred to our center. In both patients eye rubbing was present and in one patient, an ocular tic was present determining blepharospasm. Progression of keratoconus occurred in both cases and corneal collagen cross-linking (CXL) was performed. All treated eyes showed topographic stability with stable refraction and conserved visual acuity, with a follow-up period ranging from 1.5 to 2.5 years. CONCLUSION: Patients with keratoconus and TS should be observed frequently to document topographical and refractive changes, and in case of progressing disease, CXL should be performed in order to prevent further progression.

Corneal collagen cross-linking in paediatric patients affected by keratoconus.

BACKGROUND/AIMS: To evaluate the effectiveness of corneal collagen cross-linking (CXL) in paediatric patients. METHODS: Fifty-two eyes of 43 paediatric patients with progressive keratoconus were enrolled in a prospective cohort study. Corneal CXL was performed using a conventional technique with instillation of 0.1% riboflavin solution containing dextran 20% for 30 min during the soaking phase and during the 30 min ultraviolet A irradiation (3 mW/cm2). Visual outcomes, topographic keratometry, maximum keratometry (K-max), refractive astigmatism, demarcation line and endothelial cell density were measured postoperatively. RESULTS: A significant decrease of K-max from 59.30±7.08 to 57.07±6.46 (p<0.001) was observed 2 years after treatment. Uncorrected visual acuity improved from 0.59±0.41 LogMAR (logarithm of the minimum angle resolution) to 0.46±0.33 LogMAR (p=0.06) 2 years after the procedure, while best spectacle corrected visual acuity improved from 0.17±0.11 LogMAR to 0.15±0.12 LogMAR (p=0.17). Twenty-five eyes had K-max values of 60 dioptres (D) or greater. In this subgroup, K-max significantly decreased from 64.94±4.99 D to 62.25±4.42 D at 2 years (p<0.001). The demarcation line of the CXL treatment had a mean value of 249±74 µm and did not show a significant correlation with K-max flattening (Spearman r=0.019, p=0.899). Endothelial cell density remained stable 2 years after the procedure, changing from 2800±363 to 2736±659 cells/mm2 (p=0.90). CONCLUSION: CXL is an effective treatment for avoiding keratoconus progression in paediatric patients. The procedure is safe and successful in stabilising keratoconus in eyes with more advanced forms of the disease, characterised by topographic K-max values greater than 60 D.

Modified big-bubble technique compared to manual dissection deep anterior lamellar keratoplasty in the treatment of keratoconus.

PURPOSE: To evaluate the clinical findings and results of manual dissection deep anterior lamellar keratoplasty (DALK) compared to a modified big-bubble DALK technique in eyes affected by keratoconus. METHODS: Sixty eyes of 60 patients with keratoconus were treated with one of the two surgical techniques manual DALK (n = 30); big-bubble DALK (n = 30). The main outcomes measured were visual acuity, corneal topographic parameters, thickness of residual stroma and endothelial cell density (ECD). Patients were examined postoperatively at 1 month, 6 months, 1 year and 1 month after suture removal. RESULTS: Final best spectacle-corrected visual acuity (BSCVA) measured 1 month after suture removal was 0.11 ± 0.08 LogMAR in the big-bubble group compared to 0.13 ± 0.08 in the manual DALK group (p = 0.227). In patients treated with the big-bubble technique without complications (Descemet's membrane completely bared), the stromal residue was not measureable. Mean stromal residual thickness in the manual DALK group was 30.50 ± 27.60 µm. Data analysis of the manual DALK group demonstrated a significant correlation between BSCVA and residual stromal thickness; lower residual stromal thickness correlated with better BSCVA values (Spearman ρ = 0.509, p = 0.018). Postoperative ECD was similar in both groups at all intervals, with no statistically significant differences. In both groups, ECD loss was only significant during the 1- to 6-month interval (p = 0.001 and p < 0.001 in the big-bubble DALK and manual DALK groups, respectively). CONCLUSION: Manual DALK provides comparable results to big-bubble DALK. Big-bubble DALK permits faster visual recovery and is a surgical technique, which can be easily converted to manual DALK in cases of unsuccessful 'big-bubble' formation.

Deep anterior lamellar keratoplasty using an original manual technique.

AIMS: To evaluate the clinical findings and visual outcomes of deep anterior lamellar keratoplasty (DALK) using an original manual dissection technique. METHODS: 288 eyes (268 patients) with corneal pathologies without endothelial involvement were treated by DALK using an original manual dissection technique guided by a calibrated knife incision based on ultrasonic pachimetry values. Clinical records were examined retrospectively at 2 months, 6 months, 1 year and 2 years. The following outcomes were measured: visual acuity, topographic parameters, endothelial cell density and recipient stromal residue thickness. RESULTS: At the 2-year postoperative follow-up, the mean logarithm of the minimum angle of resolution best spectacle corrected visual acuity (BSCVA) was 0.131±0.087 and topographic astigmatism was 2.87±1.57 diopters. In 12 cases (4.2%) a perforation of Descemet's membrane required conversion of the procedure to penetrating keratoplasty. Mean optical coherence tomography (OCT) residue thickness (measured in 82 eyes with OCT Visante) was 31.63±24.57 µm; lower values of recipient residue thickness were significantly associated with higher BSCVA (Spearman coefficient 0.635, p< 0.001). CONCLUSION: DALK using a dry manual dissection technique provides visual, refractive and clinical results comparable to other deep lamellar techniques. Eyes with lower values of recipient residue thickness are associated with better visual acuity.

Limbal stem-cell therapy and long-term corneal regeneration.

BACKGROUND: Corneal renewal and repair are mediated by stem cells of the limbus, the narrow zone between the cornea and the bulbar conjunctiva. Ocular burns may destroy the limbus, causing limbal stem-cell deficiency. We investigated the long-term clinical results of cell therapy in patients with burn-related corneal destruction associated with limbal stem-cell deficiency, a highly disabling ocular disease. METHODS: We used autologous limbal stem cells cultivated on fibrin to treat 112 patients with corneal damage, most of whom had burn-dependent limbal stem-cell deficiency. Clinical results were assessed by means of Kaplan-Meier, Kruskal-Wallis, and univariate and multivariate logistic-regression analyses. We also assessed the clinical outcome according to the percentage of holoclone-forming stem cells, detected as cells that stain intensely (p63-bright cells) in the cultures. RESULTS: Permanent restoration of a transparent, renewing corneal epithelium was attained in 76.6% of eyes. The failures occurred within the first year. Restored eyes remained stable over time, with up to 10 years of follow-up (mean, 2.91+/-1.99; median, 1.93). In post hoc analyses, success--that is, the generation of normal epithelium on donor stroma--was associated with the percentage of p63-bright holoclone-forming stem cells in culture. Cultures in which p63-bright cells constituted more than 3% of the total number of clonogenic cells were associated with successful transplantation in 78% of patients. In contrast, cultures in which such cells made up 3% or less of the total number of cells were associated with successful transplantation in only 11% of patients. Graft failure was also associated with the type of initial ocular damage and postoperative complications. CONCLUSIONS: Cultures of limbal stem cells represent a source of cells for transplantation in the treatment of destruction of the human cornea due to burns.

Acanthamoeba keratitis with perforation after corneal crosslinking and bandage contact lens use.

A 32-year-old man with keratoconus developed corneal melting 5 days after riboflavin/ultraviolet-A corneal collagen crosslinking (CXL). Corneal scraping was positive for Acanthamoeba. The patient was unaware that he was wearing a bandage contact lens and repeatedly rinsed his face and eyelids with tap water. Because of corneal perforation, a large therapeutic keratoplasty à chaud was performed. Although CXL is considered a safe procedure, this case emphasizes the potential risks. We discuss the potential effects of deepithelialization, contact lens placement, instillation of topical nonsteroidal antiinflammatory drugs and anesthetic agents, and the possible role of apoptosis when performing CXL treatment for keratoconus.

Rapid molecular identification of fungal pathogens in corneal samples from suspected keratomycosis cases.

An increase in the incidence of fungal infections has highlighted the need for rapid and precise detection and identification methods in clinical mycology. This report describes the data obtained on corneal samples from 24 patients with suspected keratomycosis using a conventional cultural approach in parallel with PCR amplification and sequencing of the internal transcribed spacers (ITSs) of the rDNA regions. Using the cultural approach, seven samples (58.3 % of the 12 samples positive for an infectious pathogen) tested positive for a fungal aetiology, with final identification taking a mean time of more than 5 days. In two cases, diagnosis required 10 days. Using the ITS-based molecular approach, a direct diagnosis was obtained in only five of the seven fungus-positive cases (71.4 %) starting from the clinical samples, but identification was still possible in all seven cases within 24 h (by using 16 h cultures for the two remaining cases). Despite the less-than-optimal sensitivity when working directly on clinical samples, the obtained data indicate that the molecular strategy used in this study is a useful complement to the conventional diagnostic approaches used for keratomycosis and, in particular, allows precise and fast fungal identification, in response to the clinical requirements. Similar studies on larger panels of patients and on different clinical samples are required for further investigation of the clinical potential of ITS-based approaches in the diagnosis of mycotic infections.

Direct sequencing of Scedosporium apiospermum DNA in the diagnosis of a case of keratitis.

The present report describes the diagnostic strategy followed in a case of keratomycosis. Together with conventional methods, a molecular strategy that involved the direct sequencing of an amplified portion of the genome encompassing the internal transcribed spacer 1 and 2 regions and sequence analysis was used. The data highlight the diagnostic role of molecular techniques, in parallel with conventional methods, in the management of ocular infections of fungal aetiology.