Sir,
Dr Uzun1 expressed concerns with our paper published in Eye.2 We appreciate the readers' interest, and we are pleased to respond to the comments.
First, Uzun questions that whether the patients were analysed for possible NTG and/or POAG. In fact, we measured IOP of all the patients, and found that all IOP measurements were <22 mm Hg. We did not observe any glaucomatous optic disc changes including increased cup/disc ratio (>0.3). There were no significant differences between patients with scleroderma and control subjects in terms of mean IOP values. Some studies reported that IOP has a significant effect on choroidal thickness (CT), but these studies included patients with glaucoma, not healthy control subjects.3 Wei et al4 examined 3468 individuals and found that CT was not significantly associated with IOP.
Second, Uzun is concerned about the presence of any systemic diseases, history of the medications, use of alcohol or caffeinated or non-caffeinated beverages or smoking before OCT, and the systemic blood pressure measurements. None of the patients with scleroderma and control subjects did use alcohol. All participants did not have any other systemic disease except scleroderma. If any participants consumed caffeinated beverages or smoked during the examination day, we instructed not to take caffeinated beverages or smoke until next day, and we performed OCT examination on the following day. Although it has been reported that drinking of caffeinated beverages causes temporary changes in CT,5 there is no evidence that drinking of these beverages causes permanent alterations in CT. Moreover, smoking can cause temporary changes in CT, but it has been also demonstrated that CT was not significantly associated with smoking.4, 6 There were no significant differences in mean systolic and diastolic blood pressures in patients with scleroderma when compared with control subjects. Thus, we are confident that we have eliminated all confounding factors, which may have effects on CT measurements. Additionally, there is also evidence that CT was not significantly associated with blood pressure.4, 7
Finally, the patients with scleroderma have been using immunomodulator drugs. However, there is no evidence that these drugs affect CT.
The authors declare no conflict of interest.
References
- Uzun S. Comment on: Evaluation of choroidal thickness in patients with scleroderma. Eye 2016; 30: 1398. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Coskun E, Zengin O, Kenan S, Kimyon G, Erdogan Er K, Okumus S et al. Evaluation of choroidal thickness in patients with scleroderma. Eye 2016; 30(4): 588–592. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Song W, Huang P, Dong X, Li X, Zhang C. Choroidal thickness decreased in acute primary angle closure attacks with elevated intraocular pressure. Curr Eye Res 2016; 41(4): 526–531. [DOI] [PubMed] [Google Scholar]
- Wei WB, Xu L, Jonas JB, Shao L, Du KF, Wang S et al. Subfoveal choroidal thickness: the Beijing Eye Study. Ophthalmology 2013; 120(1): 175–180. [DOI] [PubMed] [Google Scholar]
- Vural AD, Kara N, Sayin N, Pirhan D, Ersan HB. Choroidal thickness changes after a single administration of coffee in healthy subjects. Retina 2014; 34(6): 1223–1228. [DOI] [PubMed] [Google Scholar]
- Ulas F, Celik F, Dogan U, Celebi S. Effect of smoking on choroidal thickness in healthy smokers. Curr Eye Res 2014; 39(5): 504–511. [DOI] [PubMed] [Google Scholar]
- Alwassia AA, Adhi M, Zhang JY, Regatieri CV, Al-Quthami A, Salem D et al. Exercise-induced acute changes in systolic blood pressure do not alter choroidal thickness as measured by a portable spectral-domain optical coherence tomography device. Retina 2013; 33(1): 160–165. [DOI] [PMC free article] [PubMed] [Google Scholar]