Unintended Fluence Test Instead Of Lasik Ablation: A Case Report

To report the case of a patient who mistakenly underwent a fluence test instead of LASIK ablation. The case highlights the importance of procedural verification, the safety of modern excimer laser platforms, and the successful resolution with subsequent LASIK surgery.

Centro Cirúrgico de Correção da Visão por Laser, Porto, Portugal 

A 49-year-old patient presented for LASIK surgery. Her ophthalmic history was unremarkable, and a thorough evaluation confirmed she was a suitable candidate. She had a treatment refraction of -3.75 -0.50×85º OR and -3.25 -1.00×75º OS. Corneal topography was normal, with a preoperative thinnest corneal thickness of 517 microns. After discussing the risks and benefits, the patient provided informed consent, and surgery was planned for the right eye first. On the day of surgery, after flap creation with a Moria One Use Plus microkeratome, instead of performing LASIK, the MEL 80™ Excimer Laser from ZEISS was inadvertently activated on the fluence test settings, completing a full fluence test cycle on the patients cornea. The stromal bed was rinsed, and the flap was repositioned and the patient was sent home on topical NSAIDs, corticosteroids, and levofloxacin. Three days post-op, the cornea was clear and a 7-micron decrease in central corneal thickness was noted, with the greatest thinning in the superior cornea. At 15 days post-op, corneal thickness remained stable, and the patient was asymptomatic. The event was explained, and the patient opted to proceed with LASIK in the right eye again. The second procedure was uneventful, and three days later, she had a residual autorefractor error of -0.25 -0.50×1º with an uncorrected VA of 20/13. She later underwent successful LASIK on the left eye with an uncorrected VA of 20/13 in both eyes at the two-month postoperative visit.

This case underscores the importance of procedural verification in refractive surgery to prevent unintended laser activation. Despite the misfire, no adverse effects occurred, and the patient achieved excellent visual outcomes. The incident highlights the safety margins of modern excimer laser platforms. Transparency in reporting such cases is essential to raise awareness, reassure colleagues, and improve patient safety. Enhanced procedural checklists may help prevent similar incidents in the future.