Outcomes Of Combined Transepithelial Phototherapeutic Keratectomy (Ptk) With Pulsed-Light Accelerated Corneal Cross-Linking In Keratoconus

We aim to report the outcomes of our cohort of patients with keratoconus who have undergone combined transepithelial phototherapeutic keratectomy (PTK) laser with corneal cross-linking (CXL).

All treatments were performed at a private clinic (OCL Vision) in London, UK.

Patients who underwent combined transepithelial PTK with CXL from June 2020 to August 2021 were included in the study.  A standardised protocol was used with all patients undergoing 58um transepithelial PTK ablation depth at a 9mm width. Pre-operative K readings of 43.0D were inputted for all cases. All eyes were treated on the Schwind Amaris platform. Patients then underwent CXL with a pulsed-light accelerated CXL protocol (30 mW/cm² for 8 min of UV-A exposure time with 1 sec on/1 sec off).

23 eyes from 15 patients were included in the study.  There were no intraoperative or post-operative complications. Patients were followed up on average for 10.6 months (range 3– 22 months).  The mean BSCVA improved from 0.2 pre-operatively to 0.1 post-operatively (p=0.02) and there was an improvement in spherical equivalent from -2.02D to -1.78D (p=0.05). The Km improved from an average of 46.5D (range 41.4 – 53.2D) to 45.9D (41.9 – 50.2) (p<0.01) and the mean Kmax improved from 53.8D (43-72.9D) to 52.4D (43.2 – 66.7D) (p<0.01). The mean SimK pre-operatively improved from 2.65 (0.3 to 5.0) to 2.33 (0.5 to 4.5) (p<0.01). 60% of patients showed an improvement in BSCVA while 74% (n= 16) showed an improvement in the Kmax post-procedure.

Combined cross linking with PTK laser is a safe and efficacious alternative to standalone CXL, with good visual and refractive outcomes.