|Year : 2015 | Volume
| Issue : 12 | Page : 930-931
Nihat Sayin1, Necip Kara2, Gokhan Pekel3, Hasan Altinkaynak4
1 Department of Ophthalmology, Kanuni Sultan Suleyman Education and Research Hospital, Istanbul, Turkey
2 Department of Ophthalmology, Gaziantep University, Gaziantep, Turkey
3 Department of Ophthalmology, Pamukkale University, Denizli, Turkey
4 Department of Ophthalmology, Ataturk Training and Research Hospital, Ankara, Turkey
|Date of Web Publication||10-Feb-2016|
Dr. Nihat Sayin
Atakent Mahallesi, 4. Cadde, C 2-7 Blok, Kat: 3 Daire: 13, Kücükcekmece, Istanbul
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Sayin N, Kara N, Pekel G, Altinkaynak H. Authors' response. Indian J Ophthalmol 2015;63:930-1
We appreciate the interest in and comments of the author concerning our article. As we addressed in our study, choroid has a very large vascular network and choroidal circulation has one of the highest rates of blood flow in humans. However, an important physiological role for the high choroidal blood flow is to help temperature regulation of the retina., Increased body temperature during exercise may lead to vasodilation and increase in choroidal blood flow. On the other hand, the previous study showed that decreased retinal temperature led to a significant decrease in choroidal blood flow. Our findings confirm the outcomes of that study. We found that choroidal thickness (CT) values increased significantly at 5 min following dynamic exercise and returned to baseline values at 15 min following the exercise. Core body temperature rises during exercise and returns to baseline values following the exercise. In conclusion, high choroidal blood flow protects photoreceptors, retina pigment epithelium, and vitreous from heat stress. It must be remembered that the measurements of CT with enhanced depth imaging optical coherence tomography (EDI-OCT) technology provide only an indirect index of the consequence of blood flow regulation in a vascular bed, yet cannot measure blood flow, volume, or velocity there. We, therefore, suggest that the EDI-OCT may be used to evaluate the issue of blood flow regulation. Furthermore, it has been reported that the body temperature of older persons is lower than that of younger people and that their tolerance of thermal changes is more limited. So that, studies are required to evaluation the changes in CT during egzersize in older and young peoples.
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Conflicts of interest
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| References|| |
Sayin N, Kara N, Pekel G, Altinkaynak H. Choroidal thickness changes after dynamic exercise as measured by spectral-domain optical coherence tomography. Indian J Ophthalmol 2015;63:445-50.
Nickla DL, Wallman J. The multifunctional choroid. Prog Retin Eye Res 2010;29:144-68.
Parver LM. Temperature modulating action of choroidal blood flow. Eye (Lond) 1991;5(Pt 2):181-5.
Parver LM, Auker CR, Carpenter DO. Choroidal blood flow. III. Reflexive control in human eyes. Arch Ophthalmol 1983;101:1604-6.
Stiehl WL, González-Lima F, Carrera A, Cuebas LM, Díaz RE. Active defence of retinal temperature during hypothermia of the eye in cats. J Physiol (Paris) 1986;81:26-33.
Wanner SP, Costa KA, Soares AD, Cardoso VN, Coimbra CC. Physical exercise-induced changes in the core body temperature of mice depend more on ambient temperature than on exercise protocol or intensity. Int J Biometeorol 2014;58:1077-85.
Parver LM, Auker C, Carpenter DO. Choroidal blood flow as a heat dissipating mechanism in the macula. Am J Ophthalmol 1980;89:641-6.
Blatteis CM. Age-dependent changes in temperature regulation – A mini review. Gerontology 2012;58:289-95.