Corneal complication after femtosecond laser-assisted cataract surgery

Abstract Rationale: The femtosecond laser LDV Z 8 is unique, and the only femtosecond laser used in ophthalmic microsurgery, which is characterized by low-energy near-infrared (1030 nm) femtosecond single pulses in the nano-Joule range and a very high repetition rate in the MHz range. To the best of our knowledge, this is the first description of unintentional partial corneal incision in the anterior part of a stroma by the femtosecond laser. Patient concerns: A 79-year-old patient was referred to our clinic for cataract surgery. On admission, we diagnosed mature cataract of the left eye and pseudophakic of the right eye. The patient was qualified for the Femtosecond Laser-Assisted Cataract Surgery (FLACS). Unexpectedly during FLACS procedure after lens fragmentation the surgeon observed unexpected paracentral incision in the cornea. Diagnosis: The corneal incision line between 4 to 8 o’clock was observed. In vivo confocal microscopy was performed to assess the morphology and depth of the corneal wound. The corneal incision covered the epithelium, Bowman's membrane and stroma of the cornea reached a depth of 336 um. Interventions: The patient was under increased ophthalmologic controls; follow up with typical ophthalmic examinations and confocal microscopy was performed. Outcomes: In 2-year follow-up period, this complication had no effect on postoperative visual function, the patient had no visual problems and obtained the final BCVA 5/5. There is no dislocation of the lens in 2 years follow-up. Lessons: Low pulse energy and high pulse frequency in the LDV Z8 causes a low traumatization of tissues. In a 2-year follow-up, the corneal incision line could be observed on the slit lamp examination without long-term visual consequences of this complication. In our opinion, the most likely cause of this complication was human error and lack of communication between medical personnel. The operation team should be alert and great caution must be exercised during the procedure and check the laser settings parameters carefully each time.