Journal of Paramedical Sciences & Rehabilitation

Journal of Paramedical Sciences & Rehabilitation

An Investigation of the Distribution of Coronal Topography Maps by Pentacam in the Rural Population of the North and South of Iran

Document Type : Original Article

Authors
M Ghasemi broomand 1
M Aghazadeh-amiri 1
F Hamidi 1
F Karimi 2
M Pakbin 3
F Jabbari-azad 3
A.A Yekta 2
M Khabazkhoob 3
A Hamidi 4
1 Department of Optometry, Faculty of Rehabilitation Science, Shahid Beheshti University of Medical Sciences, Tehran, Iran
2 Department of Optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran
3 Noor Research Center for Ophthalmic Epidemiology, Noor Eye Hospital, Tehran, Iran
4 Department of Occupational Medicine, Faculty of Medicine, Iran University of Medical Sciences, Tehran, Iran
10.22038/jpsr.2019.31047.1785
Abstract
Purpose:
To determine the distribution of corneal topographic patterns measured by Pentacam in a rural population based on age and gender.
Methods:
In this cross sectional population based study, two different rural regions in Iran were randomly selected, by random cluster sampling. Detailed optometric examination including – refraction (objective and subjective), visual acuity assessment and slit lamp evaluation and Pentacam topography were conducted for all participants.
Results:
Corneal topographic maps of 794 rural cases were evaluated. The mean age of patients was 32.1+18.53 years. A total of 398 patients (51.1%) were male and 396 patients (49.9%) were female. The most prevalent topographic pattern was Symmetric Bowtie (21.6%) and after that Superior Steepening (17.9%) and the more rare patterns were Asymmetric Bowtie with Skewed Radial Axis (AB-SRAX) (3%) and Round (5.6%). The most prevalent topographic patterns in age range from 5-20yr were Oval and Symmetric bowtie (25.9), in 21-40yr was Symmetric bowtie (27.8) and -in >40yr was the Irregular pattern (18.6).
Conclusions:
This study showed us an important information about corneal topographic patterns of Iranian rural population for the first time. Our result showed that Symmetric bowtie was the most prevalent and skewed radial axis was the rarest topographic pattern. Using this finding can help us in diagnosing and treating the corneal disorders.
Keywords
Pentacam
Keratoconus
Corneal
Rural population
Iran
Subjects
  1. Liu Z, Huang AJ, Pflugfelder SC. Evaluation of corneal thickness and topography in normal eyes using the Orbscan corneal topography system. Br J Ophthalmol 1999; 83(7): 774-778.
  2. Maguire LJ, Bourne WM. Corneal topography of early keratoconus. Am J Ophthalmol 1989; 108(2): 107-112.
  3. Hashemi H, Beiranvand A, Khabazkhoob M, Fotouhi A. Corneal topography patterns in the Tehran eye study: warning about the high prevalence of patterns with a skewed radial axis. Middle East Afr J Ophthalmol 2014; 21(1): 72-76.
  4. Buzzonetti L, Valente P, Petrocelli G. Keratoconus in Children. In: Alió JL, editor. Keratoconus: Recent Advances in Diagnosis and Treatment. Cham: Springer International Publishing 2017; 43-49.
  5. Topuz H, Ozdemir M, Cinal A, Gumusalan Y. Age-related differences in normal corneal topography. Ophthalmic Surg Lasers Imaging 2004; 35(4): 298-303.
  6. Fuchihata M, Maeda N, Toda R, Koh S, et al. Characteristics of corneal topographic and pachymetric patterns in patients with pellucid marginal corneal degeneration. Jpn J Ophthalmol 2014; 58(2): 131-138.
  7. Alvi NP, McMahon TT, Devulapally J, Chen TC, et al. Characteristics of normal corneal topography using the EyeSys corneal analysis system. J Cataract Refract Surg 1997; 23(6): 849-855.
  8. Bogan SJ, Waring GO, 3rd, Ibrahim O, et al. Classification of normal corneal topography based on computer-assisted videokeratography. Arch Ophthalmol 1990; 108(7): 945-949.
  9. Buehren T, Collins MJ, Loughridge J, Carney LG, et al. Corneal topography and accommodation. Cornea 2003; 22(4): 311-316.
  10. Reddy SP, Bansal R, Vaddavalli PK. Corneal topography and corneal thickness in children. J Pediatr Ophthalmol Strabismus 2013; 50(5): 304-310.
  11. Liu Z, Xie Y, Zhang M. Corneal topography and pachymetry in normal eyes. Zhonghua Yan Ke Za Zhi 2001; 37(2): 125-128.
  12. Ugurbas SH, Zilelioglu G. [Corneal topography in patients with congenital ptosis]. Eye (Lond) 1999; 13 ( Pt 4): 550-554.
  13. Kanpolat A, Simsek T, Alp NM. The evaluation of normal corneal topography in emmetropic eyes with computer-assisted videokeratography. CLAO J 1997; 23(3): 168-171.
  14. Goto T, Klyce SD, Zheng X, Maeda N, et al. Gender- and age-related differences in corneal topography. Cornea 2001; 20(3): 270-276.
  15. Sonmez B, Doan MP, Hamilton DR. Identification of scanning slit-beam topographic parameters important in distinguishing normal from keratoconic corneal morphologic features. Am J Ophthalmol 2007; 143(3): 401-408.
  16. Wei RH, Zhao SZ, Lim L, Tan DT. Incidence and characteristics of unilateral keratoconus classified on corneal topography. J Refract Surg 2011; 27(10): 745-751.
  17. Kim HC, Chang SD. Relationship between topographic patterns and corneal astigmatism in Korean adults. Korean J Ophthalmol 2003; 17(2): 91-96.
  18. Rabinowitz YS, Yang H, Brickman Y, Akkina J, et al. Videokeratography database of normal human corneas. Br J Ophthalmol 1996; 80(7): 610-611.
  19. Levy D, Hutchings H, Rouland JF, Guell J, et al. Videokeratographic anomalies in familial keratoconus. Ophthalmology 2004; 111(5): 867-874.
  20. MW B. Topography and Scheimpflug Imaging. J Cataract Refract Surg today 2006.
  21. Read SA, Collins MJ, Iskander DR, Davis BA. Corneal topography with Scheimpflug imaging and videokeratography: Comparative study of normal eyes. J Cataract Refract Surg 2009; 35(6): 1072‑81.
  22. Pearson AR, Soneji B, Sarvananthan N, Sandford‑Smith JH. Does ethnic origin influence the incidence or severity of keratoconus? Eye (Lond) 2000; 14 (Pt 4): 625‑8.
  23. Assiri AA, Yousuf BI, Quantock AJ, Murphy PJ. Incidence and severity of keratoconus in Asir province, Saudi Arabia. Br J Ophthalmol 2005; 89(11): 1403‑6.
  24. Waked N, Fayad AM, Fadlallah A, El Rami H. Keratoconus screening in a Lebanese students’ population. J Fr Ophtalmol 2012; 35(1): 23‑9.
  25. Rabinowitz YS, Yang H, Brickman Y, Akkina J, et al. Videokeratography database of normal human corneas. Br J Ophthalmol 1996; 80(7): 610.
  26. Riley AF, Grupcheva CN, Malik TY, Craig JP, et al. The Auckland Cataract Study: demographic, corneal topographic and ocular biometric parameters. Clin Exp Ophthalmol 2001; 29(6): 381-386.

Journal of Paramedical Sciences & Rehabilitation
Volume 8, Issue 1
Spring 2019
Pages 58-65