Kurdistan Regional Government-Iraq Ministry of higher Education &Scientific Research University of Suleiman, faculty of medical sciences

School of Medical sciences Surgery department/ophthalmology unit

The Prevalence of keratoconus in Patients with Astigmatism Who attended Shaheed Dr. Aso Hospital This Study is Submitted to The University of Sulaimani/Faculty of Medical Sciences as Partial Requirement for The Degree of High Diploma in Ophthalmology

Prepared by Dr. Ribaz Jamal Maaroof M.B.Ch. B

Supervised by Dr. Dere Latif Amin M.B.Ch. B, FEBO

September 2016

Acknowledgements Great thanks to ALLAH the most passionate and merciful.

I gratefully acknowledge the effort of my supervisor DR.Dere Latef Amen for his kind supervision and support. All my respect and appreciate to Dr.Snoor Q. Kokoy for helping me in analyzing the data and for her advice while writing this study.

Committee ‘s Declaration

We, the members of the examining committee, certify that after reading the study and examining the student in it is contents, we think it is adequate for award of the degree high diploma in ophthalmology.

Chairman Dr.Ari Rahim Zangana M.B.Ch.B/F.I.C.M.S/I.P.R.A.S Date:

Member

/ /2016

Member

Dr.Tara Mahmood Hassan

Dr.Ali A.Taqi

M.B.Ch.B/S.M.S.B(Ophth)

M.B.Ch.B/C.A.B.MS(Ophth)

Date: / / 2016.

Date:

/ /2016

Dedication

I would like to dedicate my study to my mother, father and all respected teachers.

Abstract Introduction: Keratoconus is a chronic, non-inflammatory disorder characterized by progression steepening, thinning of cornea. Keratoconus is usually presented during puberty with impairment of vision, myopia and irregular astigmatism. Diagnosis of keratoconus can be made by slit-lamp -Bio microscope and corneal videokeratoscopy findings.

Objective: is to determine the prevalence of keratoconus in patients with astigmatism in Shaheed doctor Aso Eye Hospital, Sulaimaniya.

Study Design: The study design used is a cross-sectional study which was conducted in Shaheed doctor Aso hospital, eye department, consultation room, three hundred sixty-one eyes of two hundred and seven patients with one diopter and above of corneal astigmatism included. All patients have undergone ophthalmic examinations which included visual acuity, pinhole, auto refraction, best spectacles corrected visual acuity, and fundus examination, Keratoconus was defined by clinical findings and pentacam.

Statistical Analysis: The results found are as suchlike, mean age was 29.9 years, 146 (40.4%) male and 215(59.6%) female. The prevalence of keratoconus was (4.7 %). Older age, female gender, and ocular allergy had a significant relation with keratoconus(P<0.001).

Conclusion: We concluded that the prevalence of keratoconus in Sulaimaniya was found to be higher than which was seen in comparative studies, except in Turkey. This may be related to a combination of environmental factors, allergy, female gender and older age which were thought to be significant risk factor.

i

List of abbreviations: BSCVA D KC Log MAR VKC CCT

Best spectacles corrected visual acuity Diopter Keratoconus Logarithms minimum angle of resolution Vernal keratoconjunctivitis Central Corneal Thickness

ii

List of tables: No. of the table 1 2

Title of table

Page No.

Summary of results (Demographic data) 12 Summary of different studies on prevalence of 19 keratoconus

List of figures: No. of figure

Title of figure

Page No.

1 2 3

Keratoconus signs Prevalence of keratoconus Pentacam image shows keratoconus

4

4

Percentage of types corneal astigmatism in both keratoconic and Non -keratoconic eyes Histogram showing the distribution of corneal power in eyes with keratoconus and central corneal thickness. Severity of keratoconus

13

5,6,7 8

10 11

14 15

iii

List of contents

Abstract ………………………………………………… I List of abbreviations…………………………………. II List of tables & List of figures……………….…….. lll Chapter One: Introduction and Objective ………..V Chapter Two: Patients & Methods …………………5 Chapter Three: Result ……………………………….7 Chapter Four: Discussion ………………………....16 Conclusion ,limitation& recommendations …....20 References ……………………………………………22 Appendix………………………………………………24

iv

Chapter One Introduction and Objective

v

Introduction Keratoconus is a progressive, non-inflammatory, chronic, and bilateral but asymmetrical corneal ectasia. It is characterized by corneal thinning and protrusion inferiorly. (1)(2) It is usually presented during puberty with unilateral impairment of vision due to induce of myopia and both regular and irregular astigmatism, which eventually results in scaring and loss of vision. (3) Keratoconus is usually sporadic but it may occasionally be inherited. (4)(5). It is more common in male than female. (6) Clinical features are varying according to the stage of the disease. The signs of keratoconus are including: 

Scissoring red reflex on retinoscopy.



Rizzuti’s sign: is a conical reflection on the nasal cornea when a pen light is shown from temporal side.



Vogt striae: is a deep vertical stromal line of the cornea.



Munson’s sign: is bulging of lower lid in down gaze.



Fleischer’s ring: is an iron deposition of hemosiderin pigment in epithelium and Bowman’s layers. (2)(7) The cause of keratoconus is un clear. Allergy and rubbing eye are the major risk factors. (8) (fig:1)

The severity is graded by keratometry into: 

Mild <45 D in both meridians.



Moderate 45-52 D in both meridians.



Advance 52-62 D in both meridians.



Sever > 62D in both meridians. (7)

Keratoconus can be classified according to morphological appearance into nipple cone, oval cone and global cone. (6) (7)(9) (10) Both placcido disk and scheimflug camera systems are used to confirm diagnosis and monitoring. (7)

1

Astigmatism (a= without, stigma= point) is an optical condition of the eye in which light rays from an object do not focus to a single point of retina because of variations in the curvature of the cornea or lens at different meridians. Instead, there is a set of 2 focal lines. (11) (12) There are two types of astigmatism: Regular and Irregular. Regular astigmatism: is a condition when the refractive power changes uniformly from one meridian to another. Irregular astigmatism: This type is characterized by an irregular change of refractive power in different meridian. There are multiple meridians. The eye is a frequent target of inflammation in both local and systemic allergic reactions. The vast majority of ocular allergy affects the conjunctiva. Vernal keratoconjunctivitis (VKC) is a severe form of ocular allergic conjunctivitis characterized by chronic, recurrent and bilateral inflammation of conjunctiva and cornea.VKC typically occur in male in age of around 10 years and it lasts for 5-10 years. The signs and symptoms include foreign body sensation, photophobia and copies mucous discharge. VKC is more prevalent in hot and dry areas. (15) Keratoconus is associated with systemic diseases in one hand which include; Crouzon’s syndrome, Down’s syndrome, Marfan’s syndrome, Osteogenic imperfect, and Mitral valve prolapse. In other hand with ocular association which included Vernal keratoconjunctivitis, Atopic keratoconjunctivitis, Aniridia, Lebercongenital amaurosis, and Retinitis pigmentosa. (16)

2

Objective To determine the prevalence of KC in young patients aged 12 years or more with mild to severe corneal astigmatism.

3

Vogt striae

Munson’s sign

acute hydrops

Fleischer ‘s ring

Rizzutti’s sign

Figure 1. Keratoconus signs.

4

Chapter Two Patients and Methods

.

5

Patients and Methods Study Design and Setting The samples of this cross-sectional study were included those patients who attended to Shaheed Dr. Aso Hospital eye department consultation room, Sulaimaniya city, Kurdistan region Iraq.

Sampling 361 eyes ,146 males and 215 females were included in this study. They visited hospital between March to June 2016, having one diopter of corneal astigmatism and above and 12 years old and above. All participants had undergone ophthalmic examination included visual acuity, pinhole, auto refraction, BSCVA, slit lamp examination, and pentacam.

Statistical analysis For data collection, questionnaire was organized included (Name, Age, Gender, Visual acuity, Pinhole, Best corrected visual acuity, Slit-lamp examination, Type of astigmatism, K-readings and Pentacam results). Pentacam of (Wave Light- oculyzer ll) was used, for subject’s investigation In this study, the prevalence of KC was calculated as percentages with 95% confidence intervals (CIs). The Chi-square test was used to know relation between age, gender and Keratoconus. One-way ANOVA was used to know a relation between keratoconus and degree of astigmatism.

6

Chapter Three Result

7

Result

The over all of 361 eyes of 207 patients (n=146) male (40.4%) and (n= 215) female (59.6%), and the former were significantly older than latter (P<0.001). The mean age with standard deviation was (29± 9.3) years, its range is between (12-65). The prevalence of keratoconus was (4.7%) 17 cases, 4 males (23.5%) and 13 females (76.5 %). These included 8 (95%) patients with bilateral KC and 1(5%) patient with unilateral KC. It reveals that the presence of KC was significantly associated with older age (P <0.001). Out of 17 subjected with KC no one had family history of KC. The mean cylindrical refractive error of corneal astigmatism in patients with KC was (-3.50) diopter, its range is between (-7.00 to 3.50) The mean of spherical equivalent in patients with KC was (-3.00) diopter, its range is between (-9.50 to 0.25). The cylinder power was (-1.50) D worse in keratoconic versus non-keratoconic participants (P <0.001). The steeping was located inferiorly in all eyes. Type of astigmatism in keratoconic patients, we found simple astigmatism 1(5%) patient, compound astigmatism 12(71.5%) patients and mix astigmatism 4(23.5%) patients, whereas mild and moderate severity of KC, we found 2 mild eyes (11.5%) and 15 moderate eyes (88.5%) respectively. There was no significant relation between severity of KC and degree of corneal astigmatism in keratoconic patients (p=0.11). The mean of central corneal thickness in all sample was 533.8 nm and in keratoconic patients was 471.76 nm, thinning were inferioronasally in all eyes, there was a significant relation between KC and CCT (P =0.001). Our result also showed a trend of high prevalence of oblique corneal astigmatism in eyes with KC which was 10 eyes (58.8%). There was a significant relation between severity of KC and corneal regularity(p<0.001).

8

As summarized in table 1, out of 361 eyes, 31(8.6%) eye had ocular allergy, 6(19.3%) eyes had KC (2 eyes had VKC and 4 eyes had allergy conjunctivitis), there was a significant relation between ocular allergy and KC (p<0.001). The mean of flattest meridian with standard deviation in patients with KC was (42.75±1.63) D, its range is between (38.6- 49.00), and the mean of steepest meridian with standard deviation (44.5±1.86) D, its range is between (42.0-54.9). The BCVA in eyes with KC was (0.79) log MAR, that was lower than BCVA in non keratoconic eyes (0.87) log MAR. There was a significant relation between KC and BCVA (P<0.001).

9

.

Figure 2. Prevalence of keratoconus

10

Figure 3. Pentacam image shows keratoconus.

11

Table 1. Summary of results. DEMOGRAPHIC DATA Subjects Mean age ±SD

Results 29.12±9.36, range (12-65) years Keratoconus mean age (23.2) years range (16-30) years

Male: female Prevalence of keratoconus

146:215 (40.4% :59.6%) 17 eyes (4.7%) 4 males (23.5%), 13 females (76.5%) 15 eyes mild (4.5%) ,2 eyes moderate (0.6%) -1.92, range (-7.00 to 3.50 D)

Severity of keratoconus Mean of Corneal astigmatism Type of corneal astigmatism In keratoconus

Simple 1 eye (6%) Compound 12 eyes (70.5%) Mix 4 (23.5%)

Corneal regularity Of keratoconus

With rule 5 eyes (29.5%) Against rule 2 eyes (11.8%) Oblique 10 eyes (59%)

Mean of spherical equivalent

-2.16, rang (-11.25_9.00 D)

Mean of flattest K

42.71D range (38.0-49.9) all sample Mean of flattest K in keratoconus 43.03 D

Mean of steepest K

44.58 D range (42.0-54.9) all sample Mean of steepest K in keratoconus 46.52 D 533.8 nm in all sample 471.76 nm in keratoconic patients. 8 bilateral and 1 unilateral.

CCT Laterality The mean of BCVA of right eye The mean of BCVA of left eye The mean of BCVA in eyes with KC Ocular allergy

0.85 MAR log (6/6 p) all sample In keratoconus 0.84 MAR log (6/6 p) 0.87 MAR log (6/6 p) all population In keratoconus 0.76 MAR log (6/9 p) (0.79) log MAR. (both eyes). 31 eyes (8.6%) all sample 6 eyes have keratoconus (19.3%) 25 eyes no keratoconus (80.6%)

12

Figure 4. Percentage of types corneal astigmatism in both keratoconic and Non keratoconic eyes.

13

Figure 5

Figure 6

Histogram showing the distribution of corneal

Histogram showing the distribution of corneal

Power in eyes with keratoconus.

power in eyes with keratoconus.

Figure 7. Histogram showing the distribution of central corneal thickness in all sample population.

14

Figure 8. Severity of keratoconus.

15

Chapter Four Discussion

16

Discussion

To the best of our knowledge, this is the first cross sectional study on the prevalence of KC in Kurdistan region of Iraq. Several studies have been conducted about prevalence of KC in different part of the world and the results are varied. As summarized in table (2). In the present study, the prevalence of KC is 4.7% (4700 per 100,000). This result represents only definite (clinical KC) form of KC. It is lower than the other study which conducted in Turkey 6.3% (6300 per 100,000) (17) and is far higher than the other studies from USA 0.0054%(18), Iran (shahroud )0.075%(19), Denmark 0.086%(20), Palestine 1.5% (21), Mexico 1.8% (22), India 2.3% (23), Israel 2.3% (24) and Iran(Mashhad) 2.5%(25). The mean age at diagnosis noted in our study is (29.9) years, its range is between (12-65) years which is somewhat similar to a study conducted in Turkey by Huseyin Serdarogullari which was (29.9) years range from (15-45). (17) The high prevalence rate in current study may be due to environmental factors in Iraq where the climate is characterized by dry conditions for the most year, and hot summer. Other possibility of having high prevalence in this study is sample size (361) subjects if we compare to that study in India was conducted by JOST, B. JONAS (4711) subjects(23). The relatively high prevalence of KC in this study may be due to different diagnostic methods, older studies used keratometry and retinoscopy reflex like that study which conducted in USA by Kennedy (18). Another possibility for high prevalence rate may be related to age of our sample, if we compare it to that study conducted in Mexico by Jorge, E. Valdez-Garcia which was (16.1) years (22) and the study in Palestine by Mohammad, M. shehadeh which was 20.1 years (21).

17

There is a significant difference between men and women in this study (4 male 23.5% and 13 female 76.5%( p <0.001 ) which indicates that the prevalence of KC in women is almost three times more than in men .This result is in line with a similar study in Iran (shahroud) by Hassan Hashmi which was (men 42.3% and women 57.7%) (19) , but had dissimilar result to that study in Israel conducted by Michel Millodot which was ( men prevalence 4.91% and women 1.07%) (24) .This predomination of women over men in our study may be due to higher women rate participant in our sample . Our finding suggests a significant correlation between age and the prevalence of KC which is increased with aging (P <0.001). In contrast, the finding is dissimilar to that study conducted in Iran (shahroud) by Hassan Hashemi which reported decreasing with age (19) and it is similar to that study by Mohammad, M. Shehadeh in Palestine. (21) There is no significant correlation between age and prevalence of KC in that study reported by Hassan Hashemi in Iran (Mashhad) (25). It seems that one of the main causes for this difference is the wide range of age in our study population (12-65) years. The association between VKC and KC had been reported extensively. In this study, a strong significant correlation is found between VKC and KC 6 eyes (19.3%)(P <0.001), which is similar to two studies that reported in Yemen by Salah, A. Akily (15) and Turkey by Yuksel Totan (26). Our result also shows a trend of high prevalence of oblique corneal astigmatism in eyes with KC. We haven’t found a significant correlation between the severity of KC and degree of astigmatism (P = 0.11). The result is similar to that study by Kazutaka Kamiya in japan that reported (P =0.058) (27), it is dissimilar to the study that conducted in Turkey by Huseyin Serdarogullari reported higher prevalence rates for KC was found as cylindrical power increases (17).

18

Table 2. Summary of different studies on prevalence of keratoconus. Region Turkey Iran (shahroud) Iran(Mashhad) Palestinian India Israel Denmark

Mean age

Prevalence of K.C

29.9

6.3%

50.83 26.1

0.76% 2.5%

20.1

1.5%.

49.4 24.4 No available

Mexico USA This study

16.1 25(median) 29.9

2.3% 2.34% 0.0086%

Year 2013 2013 2014 2015 2009 2011 2007

Sample size 128 4592 1027 1234 4667 981

1.8% 0.00545% 4.7%

2014 1986 2016

500 13,395 361

National patient registry 1995-2005

19

Limitation Conclusion Recommendations

20

Limitation 

The pentacam device was not available in Shaheed Dr. Aso hospital during conducting this study, and high cost in private hospitals, had a negative effect on participant’s response.



Our sample size was small due to limit time.



We didn’t have enough staff during conducting this study.

Conclusion In current study the prevalence of KC in Sulaimaniya city was higher than the comparative studies except in Turkey. Among the evaluation of risk factors, increasing age, ocular allergy, environmental factors, and oblique corneal astigmatism were significantly with keratoconus.

Recommendations  Patients with low degree of astigmatism may have KC, therefore we should consider corneal topography for those patients.

 Those who have ocular allergy ought to be well taken care of, to figure it out whether they have KC or not.

 Funding Shaheed Dr.Aso hospital to buy a newer version of corneal topography.  Good management and advice of patients with ocular allergy.

21

References 1- Naderan M, Shoar S, Rezagholizadeh F, Zolfaghari M. Characteristics and Associations of keratoconus Patients. Contact Lens and Anterior Eye. 2015;38(3):199-205. 2- Naderan M, Rajabi M, Zarrinbakhsh P. Distribution of Anterior and Posterior Corneal Astigmatism in Eyes with Keratoconus. American Journal of Ophthalmology. 2016; 167:79-87. 3- Prajna N. Aravind Faqs in ophthalmology. [Place of publication not identified]: Jaypee Brothers Medical P; 2013. 4- James B, Brown A.ophthalmology lecture notes .4th. UK: Wiley-Blackwell; 2011. 5- Dr. Zahir Mira.Rapid ophthalmology.1st .UK: Wiley- Blackwell;2013. 6- Goebels S, Käsmann-Kellner B, Eppig T, Seitz B, Langenbucher A. Can Retinoscopy Keep up in Keratoconus Diagnosis? Contact Lens and Anterior Eye. 2015;38(4):234-239. 7- Yanoff M, Duker J, Augsburg J. Ophthalmology. [Edinburgh]: Mosby Elsevier; 2009. 8- Alastair K. O. Dennison, Phillip Murray. Oxford hand book.3rd. UK: OXFORD university press ;2014. 9- Sutphin, John E. External Disease and Cornea. San Francisco, CA: AAO; 2009. 10- Williams j Benjamin, BORISH'SCLINICAL REFRACfION.2nd. USA: f Elsevier Inc.;2006. 11- Skuta, G L, Cantor, L. B, & Weiss J S. Clinical optic. San Francisco, Calif: American Academy of Ophthalmology; 2015. 12- Sunita Agarwal, Athiya Agarwal, David J Apple, Lucio Buratto, Jorge L Alió, Suresh K Pandey, Amar Agawam. Text book of ophthalmology.1st edition. New Delhi-India: Jaypee Brothers Medical Publishers (P) Ltd;2002. 13- David Atchison ,George Smith. Optics of the Human Eye.UK: Elsevier;2000. 14- A K Khurana. Comprehensive ophthalmology.4th. India: New age international;2007. 15- Al-Akily S,Bamashmus M. Ocular complications of severe vernal keratoconjunctivitis (VKC) in Yemen. Saudi Journal of Ophthalmology. 2011;25(3):291-294. 16- Kanski J. clinical ophthalmology.7th. Edinburg: ELSEVIER ;2011. 17- Huseyin Serdarogullari , Mehmet Tetikoglu ,Hatice Karahan ,Feyaz Altin , Mustafa Elcioglu. prevalence of keratoconus and subclinical keratoconus in subjects with astigmatism using pentacam derived parameters.2013;8(3):213219. 18- Kennedy R, Bourne W, Dyer J. A 48-Year Clinical and Epidemiologic Study of Keratoconus. American Journal of Ophthalmology. 1986;101(3):267-273. 22

19- Hashemi H, Beiranvand A, Khabazkhoob M, Asgari S, Emamian M, Shariati M Et al. Prevalence of Keratoconus in a Population-based Study in Shahroud. Cornea. 2013;32(11):1441-1445. 20- Nielsen K, Hjortdal J, Aagaard Nohr E, Ehlers N. Incidence and prevalence of keratoconus in Denmark. Acta Ophthalmologica Scandinavica. 2007;85(8):890892. 21- Shehadeh M, Diakonis V, Jalil S, Younis R, Qadoumi J, Al-Labadi L. Prevalence of Keratoconus Among a Palestinian Tertiary Student Population. Open Ophthalmology J. 2015;9(1):172-176. 22- Valdez-García J, Sepúlveda R, Salazar-Martínez J, Lozano-Ramírez J. Prevalence of keratoconus in an adolescent population. Revista Mexicana de Oftalmología. 2014;88(3):95-98. 23- Jonas J, Nangia V, Matin A, Kulkarni M, Bhojwani K. Prevalence and Associations of Keratoconus in Rural Maharashtra in Central India: The Central India Eye and Medical Study. American Journal of Ophthalmology. 2009;148(5):760-765. 24- Millodot M, Shneor E, Albou S, Atlani E, Gordon-Shaag A. Prevalence and Associated Factors of Keratoconus in Jerusalem: A Cross-sectional Study. Ophthalmic Epidemiology. 2011;18(2):91-97. 25- Hashemi H, Khabazkhoob M, Yazdani N, Ostadimoghaddam H, Norouzirad R, Amanzadeh K et al. The prevalence of keratoconus in a young population in Mashhad, Iran. Ophthalmic and Physiological Optics. 2014;34(5):519-527. 26- Totan Y, Hepşen İ, Çekiç O, Gündüz A, Aydın E. Incidence of keratoconus in subjects with vernal keratoconjunctivitis: Ophthalmology. 2001;108(4):824-827. 27- Kamiya K, Shimizu K, Igarashi A, Miyake T. Assessment of Anterior, Posterior, and Total Central Corneal Astigmatism in Eyes with Keratoconus. American Journal of Ophthalmology. 2015;160(5):851-857.e1.

23

Appendix

Prevalence of keratoconus in patients with astigmatism

No.

Resident

Name

Age

Sex

Occupation VA

PH

BCVA

Chief complain:

Associated with eye problem Lens Crystalline lens

pseudophakic

aphakic

Fundus examination/ optic disc HX of eye surgery Astigmatism Type of astigmatism Simple

With rule

compound

mix

against rule

K1 K2 Pentacam result 24

25

‫حكومة اقليم كردستان‪-‬العراق‬ ‫وزارة التعليم العالي والبحث العلمي‬ ‫جامعة السليمانية‬ ‫قسم العلوم الطبية‬ ‫اجلراحة وحدة قسم طب العيون‬

‫انتشار القرنية المخروطية في المرضى الذين يعانون من االستجماتيزم‬ ‫في مستشفى الشهيد الدكتور آسو‬

‫وتقدم هذه الدراسة إلى جامعة السليمانية ‪ /‬كلية العلوم الطبية كشرط الجزئي لنيل على شهادة الدبلوم‬ ‫العالي في طب العيون‬

‫أُعدت من قبل‬ ‫ريباز جمال معروف‬ ‫‪M.B.CH.B‬‬ ‫باشراف‬ ‫الدكتور ديري اللطيف امين‬ ‫‪FEBO ،B .M.B.Ch‬‬

‫أيلول ‪2016‬‬

‫حكومةتى هةريَمى كوردستان _ عراق‬ ‫وةزارةتى خويَندني باالَ و تويَذينةوةى زانسيت‬ ‫زانكؤى سليَماني‬ ‫بةشى زانسيت ثزيشكى‬ ‫بةشى نةشتةرطةرى _ ضاو‬

‫رِيَذةى باوى طليَنةى قوضةكى لةو نةخؤشانةى ئةستطيماتزميان هةية‬

‫كة سةرداني نةخؤشخانةي شةهيد د‪.‬ئاسؤيان كردووة‬ ‫ئةم تويَذينةوةية ثيَشكةشة بة زانكؤى سليَماني‪ /‬بةشى زانسيت ثزيشكى وةكو‬ ‫بةشيَك لة ثيَويسيت وةرطرتين ثلةى دبلؤمى باَال لة نةخؤشيةكاني ضاو‬ ‫ئامادةكردني‬

‫رِيَباز مجال معروف‬ ‫سةرثةرشتيار‬

‫د‪.‬ديَرىَ لتيف امني‬ ‫‪ 2016‬سيَثتمرب‬