Saturday, July 7, 2018


Just trying to compare findings of mean central corneal thickness (CCT) reported from the SAME region in DIFFERENT studies.  

The objective is to see if there are any differences in the reported mean CCT in normal individuals from the same region.

Starting with these 5 studies from Singapore and will try to add from other regions later.

Reported mean CCT in normal individuals
Chua J, Tham YC, Liao J, et al. Ethnic differences of IOP and CCT: The Singapore Epidemiology of Eye Diseases Study. Ophthalmology 2014;121:2013-22
Day AC, Machin D, Aung T, et al. CCT and glaucoma in east Asian people. Invest Ophthalmol Vis Sci. 2011;52:8407-8412
Su DH, Wong TY, Wong WL, et al. Diabetes, hyperglycemia and CCT:The Singapore Malay Eye Study. Ophthalmology. 2008;115:964-968
Pang CE, Lee KY, Su DH, et al. CCT in Chinese subjects with primary angle closure glaucoma. J Glaucoma. 2011;20:401-4
Wu RY, Zheng YF, Wong TY, et al. Relationship of CCT with optic disc parameters: The Singapore Malay Eye Study. Invest Ophthalmol Vis Sci. 2011;52:1320-24


Reported CCT
Muscat S, McKay N, Parks S et al. Repeatability and reproducibility of corneal thickness measurements by optical coherence tomography. Invest Ophthalmol Vis Sci. 2002;43:1791-5.
Average CCT= 526+/- 28 (SD)µ
Range of normal CCT= 498-576µ

Doughty MJ, Laiquzzaman M, Miller M et al. Central corneal thickness in European (white) individuals, especially children and the elderly, and assessment of its possible importance in clinical measures of intraocular pressure. Ophthalmic Physiol Opt. 2002;22:491-504
Average CCT= 0.529 +/- 0.034 mm (children)
0.533 +/- 0.033 mm (adults)
0.527 +/- 0.034 mm (elderly)

Radford SW, Lim R, Salmon JF. Comparison of Orbscan and ultrasound pachymetry in the measurement of central corneal thickness. Eye. 2004;18:434-36.
Mean CCT= Orbscan values= RE: 564.74; LE: 565 +/- 6.28µ
US pachymetry= RE: 557.74; LE: 559.03 +/- 0.13µ

Miranda MA, Radhakrishnan H, O’Donnell C. Repeatability of corneal thickness measured using an Oculus Pentacam. Optometry and Vision Science. 2009;86:266-72.
CCT= 546.23 +/- 5.24µ

O'Donnell C, Hartwig A, Radhakrishnan H. Comparison of central corneal thickness and anterior chamber depth using LenStar LS900, Pentacam and Visante AS-OCT. Cornea. 2012;9:983-88.
LenStar= 550.7 +/- 37.4µ
Pentacam= 542.7 +/- 37.9µ
Visante= 556.7 +/- 44.4µ


Mercieca K, Odogu V, Arowolo O et al. Comparing central corneal thickness in a sub-Saharan cohort to African-Americans and Afro-Caribbeans. Cornea. 2007;26:557-60.
Mean CCT= 535+/- 38µ
Gelaw Y, Kollmann M, Irunga NM et al. The influence of CCT on IOP measured by Goldmann applanation tonometer among selected Ethiopian communities. J Glaucoma. 2010;19:514-18
Mean CCT= 518+/-32.92µ
Range= 430-610µ
Lazreg S, Joseph C. CCT of North African population. Invest Ophthal Vis Sci. 2011;52:5182
38% subjects: CCT between 450-500µ
40% subjects: CCT between 500-550µ
Igamu E, Osuobeni E. Age, gender, corneal diameter, corneal curvature and CCT in Nigerians with normal IOP. J Optom. 2012;5:87-97
Mean CCT= 548+/-34.28µ
Range= 478-662µ
Ntim-Amponsah CT, Seidu AY, Essuman VA et al. A study of CCT in glaucoma and non-glaucomatous patients in a west African population. Cornea. 2012;31:1093-6.
Mean CCT= 530.53+/-35.64µ
Range= 423-650µ
Baboolal SO, Smit DP. South African Eye Study (SAES): Ethnic differences in CCT and IOP. Eye. 2018;32:749-56
Mean CCT= Africans: 514+/-31.86µ; Mixed ethnicity: 531.77+/-35.17µ; Caucasian: 549.97+/-30.51µ
Ramprasad N, Hansraj N. A review of African studies on central corneal thickness. Afr Vision Eye Health. 2016;75:a341
 A meta-analysis of various studies on CCT

Herera PL, Leiva CP, Vasile FE et al. Comparacion del espesor corneal central entre personas sanas y con glaucoma primario de angulo abierto en una poblacion de Argentina. Oftalmol Clin Exp. 2011;5:37-42.
544.73+/-26.11 µ (Right eye)
551+/-25.59 µ (Left eye)
Alonso RS, Fontes BM, Ventura MP et al. Repeatability of CCT measurement with the Pentacam HR system. Revista Brasilera de Oftalmologia. 2012;71.
541.6+/-37 µ (First visit)
543.6+/-36.9 µ (Second visit)
Valbon B, Ambrosio R, Fontes BM et al. Ocular biomechanical metrics by CorVis ST in healthy Brazilian patients. J Refract Surg. 2014;30:468-473.
547.50+/-32 µ
Valdez-Garcia JE, Hernandez-Camarena JC, Lozano-Ramirez JF et al. Correlation of age, corneal curvature and spherical equivalent with CCT. Revista Mexicana de Oftalmologia. 2017;91:172-176.
545.69+/-36.88 µ

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