Faculty Bibliography

BACKGROUND:Nasal deformity is a common disorder in Wegener granulomatosis, which is produced by polyangitis of medium-sized vessels. This process may cause necrosis and destruction of the nasal mucosa and osteocartilaginous framework. At this time, there is a lack of published data on nasal deformities associated with Wegener granulomatosis. METHODS:We present a 53-year-old woman with completely necrotized nasal lining and osteocartilage. The patient had a history of granulomatosis with polyangitis that was currently in remission. We reconstructed the patient's nose with fifth and sixth rib cartilages over 3 successive surgeries over a 2-year period. RESULTS:During the 3-year follow-up period, neither infection nor significant cartilage graft resorption was observed, and the aesthetic result was acceptable both to the patient and her physicians. CONCLUSIONS:In spite of contamination to the nasal lining and immune-compromising medications, nasal reconstruction is usually successful when considering these factors. Access to strong and abundant fifth or sixth rib cartilage presents an opportunity to reconstruct nasal destruction due to iatrogenic or autoimmune processes.

PURPOSE/OBJECTIVE:To compare the 1-year results of total versus partial epithelium removal in corneal cross-linking in the treatment of progressive keratoconus. METHODS:This retrospective study compared the results of total (the total group) versus partial (the partial group) approaches of epithelium removal in corneal cross-linking. Eighty eyes of 65 patients (40 eyes in each group) were enrolled. The mean age of the participants was 25.48 ± 4.80 years and 62.5% were male. One-year changes in vision parameters, refraction, and Pentacam (Oculus Optikgeräte GmbH, Wetzlar, Germany) indices were compared between the two groups using repeated measures analysis of variance. RESULTS:One year after corneal cross-linking, uncorrected distance visual acuity in the total and partial group improved by 0.13 ± 0.42 and 0.12 ± 0.36 logMAR (P = .447), respectively, and corrected distance visual acuity improved by 0.00 ± 0.19 and 0.13 ± 0.20 logMAR (P = .001), respectively. Spherical equivalent decreased by 0.44 ± 1.25 diopters (D) in the total group and 0.56 ± 1.47 D in the partial group (P = .710). The decrease in maximum keratometry was 0.39 ± 0.93 and 0.01 ± 0.95 D in the total and partial group, respectively (P = .037), and the decrease in mean keratometry was 0.42 ± 0.93 and 0.00 ± 0.65 D (P = .015), respectively. Central corneal thickness decreased by 18.39 ± 20.66 μm in the total group and 0.11 ± 13.29 μm in the partial group (P < .001). CONCLUSIONS:One year after corneal cross-linking, both approaches showed similar results in terms of uncorrected distance visual acuity. With the partial approach, there was slightly better corrected distance visual acuity improvement and central corneal thickness maintenance, but slightly better corneal flattening was achieved with the total removal. Long-term studies are needed to compare these two approaches in terms of stability of results and stopping the progression of keratoconus.

This article discusses corneal cross-linking (CXL) and how it transitioned from a modality for treating corneal ectatic disorders to an inventive means of treating infectious keratitis. Initially, CXL was successfully developed to halt the progression of ectatic diseases such as keratoconus, using the standard Dresden protocol. Later, indications were extended to treat iatrogenic ectasia developing after laser-assisted in situ keratomileusis (LASIK) and photo-refractive keratectomy (PRK). At the time, it had been postulated that the combination of ultraviolet light with riboflavin could not only biomechanically strengthen the cornea but also was capable of destroying living cells and organisms including keratocytes and pathogens. Thus a new and innovative concept of treatment for infectious keratitis emerged through the use of CXL technology. Initially only advanced infectious melting ulcers resisting standard microbicidal therapy were treated with CXL in addition to standard therapy. In subsequent studies CXL was also used to treat bacterial keratitis as first line therapy without the use of concomitant antibiotic therapy. With the increasing interest in CXL technology to treat infectious keratitis and to clearly separate its use from the treatment of ectatic disorders, a new term was adopted at the 9(th) CXL congress in Dublin for this specific indication: PACK-CXL (photoactivated chromophore for infectious keratitis). PACK-CXL has the potential to eventually become an interesting alternative to standard antibiotic therapy in treating infectious corneal disorders, and may help reduce the global burden of microbial resistance to antibiotics and other therapeutic agents.

Since its inception in the late 1990s, corneal cross-linking has grown from an interesting concept to a primary treatment for corneal ectatic disease worldwide. Using a combination of ultraviolet-A light and a chromophore (vitamin B2, riboflavin), the cornea can be stiffened, usually with a single application, and progressive thinning diseases such as keratoconus arrested. Despite being in clinical use for many years, some of the underlying processes, such as the role of oxygen and the optimal treatment times, are still being worked out. More than a treatment technique, corneal cross-links represent a physiological principle of connective tissue, which may explain the enormous versatility of the method. We highlight the history of corneal cross-linking, the scientific underpinnings of current techniques, evolving clinical treatment parameters, and the use of cross-linking in combination with refractive surgery and for the treatment of infectious keratitis.

PURPOSE/OBJECTIVE:To investigate whether optimized photoactivated chromophore for keratitis-corneal collagen cross-linking (PACK-CXL) treatment settings allow accelerating treatment while maintaining antibacterial efficacy. METHODS:Staphylococcus aureus and Pseudomonas aeruginosa strains were irradiated with ultraviolet-A light of equal fluence but different intensity settings (18 mW/cm² for 5 minutes and 36 mW/cm² for 2.5 minutes). The killing rate was determined by comparing the number of colony-forming units between cross-linked specimens and non-irradiated controls. The potential additional effect of 0.001% benzalkonium chloride was also investigated. RESULTS:The killing rates for Staphylococcus aureus were 92.5% ± 5.5% (5 minutes at 18 mW/cm²) and 94.4% ± 2.9% (2.5 minutes at 36 mW/cm²). For Pseudomonas aeruginosa, the killing rates were 93.2% ± 8.3% (5 minutes at 18 mW/cm²) and 92.9% ± 5.0% (2.5 minutes at 36 mW/cm²). The presence of benzalkonium chloride in the riboflavin solution did not increase the killing rate significantly. CONCLUSIONS:The antibacterial efficacy of PACK-CXL follows the Bunsen-Roscoe law of reciprocity and can be maintained even when the irradiation intensity is considerably increased. These optimized settings may allow a shortened treatment time in the future for PACK-CXL and thus help facilitate the transition from the operating room to the slit lamp for treatment.

PURPOSE/OBJECTIVE:To report the use of accelerated photoactivated chromophore for keratitis-corneal collagen cross-linking (PACK-CXL) as a first-line treatment in a patient with an atypical fungal keratitis. METHODS:Case report and literature review. RESULTS:A patient who presented with a painful peripheral corneal infiltrate underwent PACK-CXL with a local limited abrasion and accelerated ultraviolet-A irradiation at 365 μm and 9 mW/cm² for 10 minutes. Cultures grew Aureobasidium pullulans. The corneal epithelium closed completely within 3 days and the infiltrate was completely eradicated without administration of antibiotics. CONCLUSIONS:Accelerated PACK-CXL was successfully used as a first-line and sole treatment in a case of early fungal keratitis caused by Aureobasidium pullulans. Further characterization of the antifungal effect of PACK-CXL is needed in prospective studies.