Daniel Barthelmes

Klinische Monatsblatter fur Augenheilkunde • April 16, 2025

Maximilian Jacobi, Daniel Muth, Robert Blum, Daniel Barthelmes, Sandrine Zweifel, Frank Blaser

Corneal wound contracture, also called corneal wound burn or phaco burn, is a rare but severe complication that can occur with cataract operation [1]. Epidemiological studies indicate an occurrence of less than 0.037% in all cataract surgeries (or 1 : 3 000). It describes a coagulation of the phaco tunnel caused by excessive heat generated by the phaco needle during phacoemulsification [2]. Temperatures above 60 °C cause a destruction of the collagen fibres in the corneal stroma [2], [3], [4]. This causes necrosis, which results in corneal oedema. A corneal wound burn results from a combination of excessive heat generated by the phaco needle as well as insufficient cooling by irrigation fluid [1], [5], [6]. Signs of phaco burn include a sudden occurrence of corneal oedema around the phaco tunnel, with gaping wound lips and an increasingly instable anterior chamber [7], [8]. The phacoemulsification technique plays a major role for the occurrence of phaco burns. Risk factors include increased phacoemulsification time and high phacoemulsification energy [9], [10]. Consequently, chopping techniques have been reported to bear a lower risk for phaco burns than divide and conquer techniques due to less phaco energy needed [9], [10]. Another factor predisposing the possibility of a corneal wound burn is the width of the phaco tunnel. If the tunnel is too narrow, the irrigation ports will be pressed against the walls of the tunnel during phacoemulsification [3]. This can result in a blockage of irrigation, which can lead to temperature increase of the phaco needle. Ocular viscoelastic devices (OVDs) can also cause blockage of the irrigation ports. Furthermore, the energy released by phacoemulsification varies depending on the OVD used, with higher density OVDs carrying a higher risk of phaco burn [4]. Finally, overfilling the anterior chamber with an OVD reduces flow of irrigation fluid and increases the risk of excessive heat buildup [4]. In the this article, we present a case series of five eyes of five patients that developed a corneal wound burn during cataract surgery and were referred as an emergency to the Department of Ophthalmology of the University Hospital Zurich, University of Zurich, Switzerland. An overview of the cases and the respective treatments, complications, and outcomes are given in [Table 1].

Klinische Monatsblatter Fur Augenheilkunde • April 16, 2025

Frank Blaser, Isabelle Meneau, Jürg Wiedler, Olga Lamprecht, Daniel Barthelmes, Sandrine Zweifel, Philip Perschak, Maximilian Robert Wiest, Fabienne Fierz, Sadiq Said, Anahita Bajka

Background: According to the European Pharmacopoeia, multidose containers for eye drops must either contain antimicrobial agents, preservatives, or be fitted with filters or non-return valves to prevent microbial contamination after opening. Vials for single-day use do not have filters or non-return valves. The aim of this study is to demonstrate the safety of reclosable vials (ophtioles) containing unpreserved autologous serum eye drops (ASEDs) by evaluating their sterility during single-day use. Methods: Two types of reclosable ophtioles were evaluated, one with a screw cap (Meise System, Heinz Meise GmbH, Schalksmühle, Germany) and the other one with a plug cap (COL System, BIOMED DEVICE S. R. L., Modena, Italy). Drop application over 12 hours was simulated in the laboratory following the manufacturer's instructions. For the Meise System, drops were applied at 2-hour intervals, while for the COL System, drops were applied at 1-hour intervals. Each application involved inoculating a chocolate-agar PolyViteX plate (PolyViteX, bioMérieux SA, Marcy-l'Étoile, France) with two drops spaced apart on the same plate and then incubating the plate. After 24 hours, a final inoculation was performed to check for sterility, and the plates were scored after 24 and 48 hours of incubation. Results: In the Meise System test series, 12 vials were tested, providing 192 measurements over 12 hours with a 2-hour application interval. With the COL System, 16 vials were tested, resulting in 448 measurements with a 1-hour application interval over 12 hours. Neither the Meise nor the COL System showed contamination of any application after 24 hours of incubation. After 48 hours of incubation, two vials of the Meise System showed a contamination in one measurement, but subsequent applications were sterile again. In the COL System, nine measurements in seven vials were positive. In three of these vials, the last application at 24 hours showed contamination after 48 hours of incubation, where no further drops were applied. Conclusions: The study confirms the sterility of ASEDs in two reclosable types of ophtiole systems during single-day use in laboratory-simulated conditions within 12 hours of application and 24 hours of incubation time. This is consistent with our several years of clinical experience of the absence of ocular infections caused by the use of ASEDs in the described ophtioles.

Ophthalmology And Therapy • March 18, 2025

H Mhmud, J Vermeulen, O A Tigchelaar Besling, F Verbraak, D Barthelmes, M Gillies, T Ponsioen, Caroline C Klaver

Background: To evaluate long-term outcomes of anti-VEGF therapy for neovascular age-related macular degeneration (nAMD) in the Netherlands (NL), where bevacizumab is the mandated first-line drug, compared to high-income countries using ranibizumab or aflibercept as initial treatments. Methods: Five-year data from the Fight Retinal Blindness! (FRB) registry, a real-world prospective registry, were analyzed. Outcomes from 1473 Dutch eyes (1229 patients) treated with bevacizumab were compared with 7144 eyes (5884 patients) in a reference group (RG) from 13 socioeconomically similar countries. The primary outcome was mean visual acuity (VA) at yearly intervals; secondary outcomes included injection frequency and switching rates to alternative anti-VEGF agents. Results: Throughout the 60 months, mean VA was consistently higher in Dutch eyes (baseline: NL 60.2 vs. RG 59.2; 60 months: NL 64.9 vs. RG 62.6). The Dutch group cumulatively received 14.5 more injections over 5 years and had a higher rate of switching (70.9% vs. 50.9%) with a shorter median time to switching (11.9 months vs. 17.7 months). Conclusions: Patients treated in Dutch FRB! clinics have good long-term outcomes with a 2.3-letter higher mean VA at the 60-month timepoint compared to FRB! clinics in the RG. The Dutch patients, who began treatment with bevacizumab, received 14.5 more injections over 5 years and had a 40% higher rate of switching to an alternative drug, with switching occurring 5.8 months earlier. This study highlights the benefits of early and more intensive management to optimize visual outcomes, which appear more important than the choice and price of the first-line drug.

Klinische Monatsblatter Fur Augenheilkunde • February 27, 2025

Philipp Perschak, Sadiq Said, Simone Metzler, Sandrine Zweifel, Daniel Barthelmes, Dominique Hermann, Didier Herrmann, Farhad Hafezi, Léonard Kollros, Martina Bosch, Frank Blaser

Background: If used properly, contact lenses (CLs) provide a safe and effective alternative to eyeglasses for refractive error correction. However, often due to patient noncompliance, CL-related complications may occur, such as discomfort, dry eye, as well as serious conditions like infectious keratitis. Our study aimed to assess the perceived knowledge and behavior of CL wearers in Switzerland regarding the handling of CLs and associated ocular health risks. Methods: This investigator-initiated, cross-sectional, qualitative, multicenter study was conducted in Switzerland from August 2023 to August 2024. After verbal consent, CL wearers were interviewed using a structured survey. The questionnaire explored participants' demographics, their perceived knowledge of the overall handling of CLs and associated health risks, as well as their behavior in two emergency scenarios involving monocular redness or pain. The descriptive statistical analysis was performed using Microsoft Excel (Microsoft Corp., Redmond, WA, USA). Figures were created with Prism version 10.2.3 (GraphPad Software, San Francisco, CA, USA). Results: A total of 172 participants with a median (IQR [range]) age of 39 (27 to 54 [10 to 82]) years were interviewed, whereby 81 (47.1%) were female. Myopia (61.0%) and keratoconus (30.2%) were the most reported indications for CL use. In terms of overall CL handling, 91.3% of participants felt well or sufficiently informed, whereas this was the case of 66.3% regarding CL-related health risks. In the scenario involving eye redness during CL use, 135 of 175 (77.1%) responses did not mention seeking professional advice, while 25 (14.3%) indicated visiting an ophthalmologist within 1 day of symptom onset. In the event of monocular pain, 67 of 179 (37.4%) responses did not consider seeking professional care, whereas 86 (48.0%) included consulting an ophthalmologist. Conclusions: This study provides insight into the unmet educational need of CL wearers, especially regarding CL-related complications. Participants generally felt better informed about overall CL handling than about the potential health risks. This information discrepancy is reflected by their responses to scenarios involving monocular redness or pain, where a considerable number of participants failed to react adequately. Further studies are warranted to explore effective, practical strategies for improving patient awareness and behavior.

Klinische Monatsblatter Fur Augenheilkunde • February 27, 2025

Frank Blaser, Isabelle Meneau, Jana Schneider, Jürg Wiedler, Hanspeter Hinrikson, Daniel Barthelmes, Sandrine Zweifel, Anahita Bajka, Sadiq Said, Maximilian Robert Wiest

Objective: For specific samples, there are different methods and requirements for testing sterility. Blood and blood products are analyzed using automated blood culture methods, while pharmacopeial sterility is assessed using membrane filtration or direct inoculation according to the European Pharmacopoeia (Ph. Eur. 2.6.1.) to detect microbial growth. As autologous serum eye drops (ASEDs) may be viewed as both a blood product and a classical drug, the Swiss legislator has classified these as non-standardizable drugs, and thus, the pharmacopeial requirements apply. This study investigates ASED preparations with respect to the performance of a common automated blood culture system, BD BACTEC, in detecting aerobic and anaerobic bacteria and fungi in ASED preparations, with pharmacopeial sterility testing using agar plate cultures. Methods: Based on the European Pharmacopoeia, we inoculated sterile filtered blood serum with BioBalls of the six reference strains at a low concentration of three colony-forming units per milliliter (CFU/mL). A test battery of three different BD BACTEC culture media (hereafter referred to as Trio-BACTEC : BD BACTEC Plus Aerobic/F-Medium, BD BACTEC Lytic/10 Anaerobic/F-Medium, BD BACTEC Mycosis IC/F-Medium) and three agar plates [Tryptic Soy Agar (TSA), Chocolate Blood Agar, Sabouraud's Dextrose Agar] were inoculated per strain. We incubated the Trio- BACTEC in the BD BACTEC Blood Culture System at 35 °C for 5 days, the TSA and Chocolate plates at 35 °C for 5 days, and the Sabouraud plates at 25 °C for 7 days. We confirmed positive growth signals by microscopy or MALDI-ToF mass spectrometry and included negative controls. Results: We detected all reference strains using BACTEC and agar plates. No growth was observed in the negative controls. Overall, growth detection by BACTEC and agar plates was comparable, except for Aspergillus brasiliensis and Candida albicans, which was detected after 1 day on solid media and after 2 days on BACTEC. Conclusions: This study demonstrates the comparability of sensitivity and detection speed using the automated blood culture method and agar plates for sterility validation of ASED, even at low bacterial and fungal contamination levels.