We thank Galvis and associates for their comments and for their interest in our paper “Terrien Marginal Degeneration: Clinical Characteristics and Outcomes.”

In our study, 7 of 25 patients (28%) had unilateral disease. We did not have complete bilateral topographic data for all these patients, and thus could not provide conclusions about the features of the contralateral eyes as to whether they were clinically normal with or without topographic abnormalities. In our study, the diagnostic criteria used to define Terrien marginal degeneration were primarily based on clinical examination documented by evidence of peripheral corneal thinning, superficial vascularization, and lipid deposition. However, with additional complete topographic information, there may be cases that are indeed bilateral but asymmetric, as highlighted by the cases reported by Fernandes with normal slit-lamp examination but tomographic changes in Orbscan IIz examination.

Our surgical intervention rates may be higher, given the tertiary nature of our center. However, we agree with Galvis and associates that Terrien degeneration can certainly be managed conservatively by observation. In our practice, we have also used glue patch techniques for many perforations, including for recent Terrien cases not included in this patient series. We advocate considering surgical intervention for eyes that are at imminent risk for perforation, especially if a patient has an active lifestyle, since in our series perforated corneas had worse visual outcomes with an average decrease in best spectacle-corrected visual acuity (BSCVA) from 20/58 to 20/187 before and after perforation, with trauma-related perforation having the worst prognosis. Residual regular and/or irregular astigmatism may exist after lamellar keratoplasty, causing limitations in BSCVA. Various modalities individually or in combination, depending on patient suitability, are offered for surgical correction of residual astigmatism, including laser astigmatic keratotomies, topography-guided phototherapeutic keratectomy, and lens extraction with toric intraocular lens implantation. Patients may decline further intervention, as they are accustomed to functioning with their good eye and satisfied with the reduced risk of perforation.

In conclusion, the surgical approach to Terrien degeneration requires a full informed consent discussion with the patient (including the risk of decreased postoperative BSCVA from irregular astigmatism). These patients should be educated on the risks of spontaneous and trauma-related perforation and the need for protective eyewear.