More information about text formats
We thank Sarmad et al. for their interest in our publication. Our study is a retrospective review of several variables regarding non-traumatic corneal perforations (1). In handling clinical records for a retrospective analysis, missing variables represent a common problem. In relation to the location of corneal perforation, information was not available in 25 eyes thus the number does not match. Hence, in consideration of this inevitable flaw we decided not to include the anatomical location of perforation into the model presented in the manuscript, therefore all the variables included in this statistical model had no missing values.
Clinical treatment of corneal perforation is often complex and a single intervention may not address the patient full pathology, therefore more than one treatment is frequently used. (2) This explains the increased number of initial treatments in the first clinical intervention, one example of this scenario are the patients needing simultaneous tectonic penetrating keratoplasty to restore ocular integrity and concurrent amniotic membrane transplantation to aid in the control of ocular surface. (2)(3)
These two situations might not be precise in our manuscript, but we take the opportunity of this letter to clarify them. However, that is unquestionably far from compromising the validity of the conclusions. Definitely, as any retrospective study, and as we mention in the discussion of our article, there are li...
These two situations might not be precise in our manuscript, but we take the opportunity of this letter to clarify them. However, that is unquestionably far from compromising the validity of the conclusions. Definitely, as any retrospective study, and as we mention in the discussion of our article, there are limitations including the lack of a standard algorithm of treatment and the impossibility to include other variables that might alter the final outcomes of the patients. Therefore, and as we also discussed, this imply that the conclusions presented must be taken with caution. Thus, when interpreting the results of a retrospective study it is important to understand and be aware of the possible bias and limitations, allowing the reader to take advantage of the many strengths of this design into incorporation of knowledge into their daily clinical practice. (4)
1) Loya-Garcia D, Serna-Ojeda JC, Pedro-Aguilar L, et al. Non-traumatic corneal perforations: aetiology, treatment and outcomes. Br J Ophthalmol. 2017;101(5):634-639.
2) Jhanji V, Young AL, Mehta JS, et al. Management of corneal perforation. Surv Ophthalmol. 2011;56(6):522-38.
3) Dua HS, Gomes JA, King AJ, et al. The Amniotic Membrane in Ophthalmology. Surv Opthalmol 2004; 49:51-77.
4) Euser AM, Zoccali C, Jager KJ, et al. Cohort studies: prospective versus retrospective. Nephron Clin Pract. 2009;113(3):c214-7.
We read your article titled- Non-traumatic corneal perforations: aetiology, treatment and outcomes: with great interest. Corneal perforation is an acute ophthalmic emergency. This review describes the aetiology, plausible location and the multiple ways to approach the management of this condition in a very a systematic manner.
We do appreciate the organised mode of stratification and care of non- traumatic corneal perforation presented in the article. However, although the results are interesting, we feel that caution should be exercised when drawing conclusions from this data.
Initially, in results there are 127 eyes of 116 patients under the review. However, while describing the anatomical location of the perforation, only 102 eyes have been accounted for, with no records for the remaining 25 eyes. This would change the calculated p value significantly.
Similarly, where the initial treatments for perforations were being reviewed 133 eyes were mentioned as treated, thus including six extra unaccounted for eyes to the total. This would seriously jeopardise the authenticity of the calculated results.
Hence, there appears to be serious doubts regarding the validity of the conclusions of this review. A clearer and more detailed explanation or a recalculation of the results is warranted in this regard.