Commentary: Ablating the erosions - Transepithelial phototherapeutic keratectomy for post-traumatic recurrent corneal erosions.

Recurrent corneal erosions (RCEs) are a common cause of ocular morbidity in the form of episodes of pain, watering of the eye, increased sensitivity to light, and blurring of vision, accounting for socio-psychological suffering of the patients.[1] Trauma is a major cause of RCE, with some studies reporting it to be causative in more than half of the documented cases, either independently or in conjunction with epithelial basement membrane corneal dystrophy.[2] A plethora of treatment options have been cited in the literature, ranging from conservative options in the form of lubricant eye drops, autologous serum eye drops, oral tetracyclines, and bandage contact lenses to interventions such as alcohol delamination, mechanical debridement, superficial keratectomy, diamond burr polishing, neodymium-doped yttrium aluminum garnet (Nd:YAG) laser treatment, needle anterior stromal puncture, micro diathermy, and excimer laser phototherapeutic keratectomy (PTK), emphasizing the lack of a uniform modality of effective treatment with low recurrence rates.[3] The article in the current issue of Indian Journal of Ophthalmology titled, “Transepithelial phototherapeutic keratectomy for post-traumatic recurrent corneal erosions” (IJO_2340_21), highlights the effective role of this relatively new intervention for RCE, prompting this commentary.[4]

The findings of the aforementioned study revealed that 100% (24/24) of the eyes with post-traumatic RCE treated with PTK recovered without any complications of further erosions or requirement of any retreatment.[4] A similar study by Giessler (Ophthalmologe 2001) reported persistence of symptoms in 17.8% of 45 cases with requirement of retreatment in two cases.[5] The authors in the aforesaid study designed central corneal ablation of 75-mm depth and a maximum peripheral ablation of 95-mm depth by using a “TransPTK” mode excimer laser which might account for the improved results. Recurrence rates as high as 56.6% and 14.8% have previously been reported for conservative management and diamond burr polishing, respectively, by Suri et al.[6] (Am J Ophthalmol, 2013), thus establishing the effectiveness of this treatment modality.[4] TransPTK, by strengthening the adhesion of the basal epithelial cells to the basement membrane, caters to the underlying pathology of RCE in the form of abnormal formation of hemidesmosomes/anchoring filaments at the basal layer of the corneal epithelium, thus yielding better outcomes.

The fact that the refractive status of the patients remained stable after 1 year in terms of uncorrected distance visual acuity, best-corrected distance visual acuity, spherical equivalent, and refractive cylinders is an encouraging observation in contrast to various degrees of astigmatism reported by other methods such as diamond burr superficial keratectomy.[47]

The mean time until corneal re-epithelization reported in the study was 4.12 ± 0.95 days with no postoperative corneal haze as compared to a duration of 5 weeks and 9 weeks for therapeutic contact lens and topical lubrication, respectively, emphasizing the fact that transepithelial PTK can prove to be a promising intervention for RCE, with minimal postoperative complications and good patient acceptance.[48]

The findings of this study invite further large-scale randomized control trials to draw standardized parameters for laser ablation in RCE and to test whether transepithelial PTK can be extrapolated to non-traumatic, mixed etiology, and macro-erosion RCE as well.

Considering the prominence of post-traumatic RCE in terms of the significant ocular morbidity it inflicts, varied treatment modalities with unsatisfactory outcomes, and nuance of recurrence, transepithelial PTK surfaces as a promising minimally invasive intervention with satisfactory outcomes, ease of repeatability, faster visual recovery, and negligible adverse effects.