SURGICAL MANAGEMENT OF PROGRESSIVE AND RECURRENT TRUE PTERYGIUM IN RURAL AREAS

1

SYNOPSIS OF THE DISSERTATION SUBMITTED TO

RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES,KARNATAKA, BANGALORE

IN PARTIAL FULFILLMENT OF THE REGULATIONS FOR THE AWARD OF

M.S.DEGREE IN OPHTHALMOLOGYSUBMITTED

DR.DINESH.P

UNDER THE GUIDANCE OF

DR.JAYRAM.RPROFESSOR OF OPHTHALMLOGYSAH & RC.AIMS.B.G.NAGARA

ADICHUNCHANAGIRI INSTITUTE OF MEDICAL SCIENCE, B.G.NAGARA

RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES

KARNATAKA, BANGALORE

ANNEXURE II

PROFORMA FOR REGISTRATION OF SUBJECTS OF DISSERTATION

1 NAME OF THE CANDIDATE AND ADDRESS( in block letters)

DR.DINESH.P# 79, KALPATHARU BHAVANA, P.G HOSTEL

A.I.M.S, B.G.NAGARA. NAGAMANGALA TALUK, MANDYA DISTRICT-571448

KARNATAKA.

2 NAME OF THE INSTITUTION ADICHUNCHANAGIRI INSTITUTE OF MEDICAL SCIENCES, B.G.NAGARA.

MANDYA DISTRICT-571448.

3 COURSE OF STUDY AND SUBJECT M.S.[OPHTHALMOLOGY]

4 DATE OF ADMISSION TO COURSE 15/MAY/2009

5 TITLE OF THE TOPICSURGICAL MANAGEMENT OF PROGRESSIVE

AND RECURRENT TRUE PTERYGIUM IN RURAL AREA.

6 BRIEF RESUME OF INTENEDED WORK

6.1 NEED FOR THE STUDY

6.2 REVIEW OF LITERATURE

6.3 OBJECTIVES OF THE STUDY

APPENDIX I

7 MATERIALS AND METHODS APPENDIX II

2

7.1 SOURCE OF DATA : DEPARTMENT OF OPHTHALMOLOGY SRI ADICHUNCUNAGIRI INSTITUTE

OF MEDICAL SCIENCES. MANDYA DISTRICT AND SURROUNDING

RURAL AREAS.

7.2 DOES THE STUDY REQUIRE ANYINVESTIGATIONS OR INTERVENTIONS YESTO BE CONDUCTED ON PATIENTS OR OTHER APPENDIX IIBANIMALS, IF SO PLEASE DESCRIBE BRIEFLY

7.3 HAS ETHICAL CLEARANCE BEENOBTAINED FORM YOUR INSTITUTION IN CASE OF 7.2

YES

8 LIST OF REFERENCES (ABOUT 4-6) APPENDIX III

9 SIGNATURE OF CANDIDATE

10 REMARKS OF THE GUIDE IT HAS BEEN OBSERVED THAT THE INCIDENCE OF TRUE PROGRESSIVE PTERYGIUM APPEARS TO BE MORE COMMON IN RURAL AREAS RATHER THAN THE URBAN AREAS; OWING TO THE OCCUPATIONAL AND ENVIRONMENTAL FACTORS. THE STUDY IS INTENDED TO EVALUTATE THE SURGICAL MANAGEMENT OF PTERYGIUM, WHICH HAS LEAST INCIDENCE OF RECURRENCE.

11 NAME & DESIGNATION OF

(IN BLOCK LETTERS)

11.1 GUIDE DR.JAYRAM.RM.B.B.S , M.S OPHTHALMOLOGY

3

PROFESSORDEPARTMENT OF OPHTHALMOLOGY

SRI ADICHUNCHUNAGIRIINSTITUTE OF MEDICAL SCIENCES.

11.2 SIGNATURE

11.3 CO-GUIDE (IF ANY)

NAME :

SIGNATURE :

11.4 REMARKS

11.5 HEAD OF DEPARTMENT DR PADMINI.H.RM.B.B.S ,D.OM.S, M.S OPHTHALMOLOGY

PROFESSOR AND H.O.DDEPARTMENT OF OPHTHALMOLOGY

SRI ADICHUNCHUNAGIRIINSTITUTE OF MEDICAL SCIENCES.

11.6 SIGNATURE

12.1 REMARKS OF CHAIRMAN AND PRINCIPAL

12.2 SIGNATURE

APPENDIX-I

4

6.0 BRIEF RESUME OF THE INTENDED WORK:

6.1 NEED FOR THE STUDY:

The taluk in which our institution is located comes under the Mandya Sub-division of Mandya district. The area of the taluk is 719.10 Sq.Kms. the total population of the taluk is 4, 05,612. Out of which 2, 05,798 are male and 1, 99,814 are female. About 68% of the population lives in rural area. Agriculture is the main occupation of the people in this taluk. As such they are constantly exposed for wind, dust, UV rays, making them prone for Pterygium. Since medical management of pterygium has no cure, surgical management is intended to cure and prevention of its recurrence.My present study is undertaken to assess the surgical management of progressive true/recurrent pterygium, and to assess how the surgical management can provide complete cure and prevention of its recurrence.

APPENDIX-IB

5

6.2 REVIEW OF LITERATURE

Pterygium takes its name from the Greek word for wing and was described by Hippocrates, Galen and others.

Pterygium was described as early as 100 BC by the Indian physician Sushrutha.

Fuch’s wrote the classic treatise in 1892 which dominated ophthalmologist understanding for 50 years.He first popularized the differentiation of Pterygium into either:

The thick, vascular progressive type The thin, white non-progressive type

He felt that a temporal Pterygium is never seen without a nasal Pterygium, he believed that a Pterygium always originates from a pingueculum.Geographic distribution:Pterygium is seen in all parts of the world but is more common near the equator.Pterygium belt is commonly seen in India which is a part of the ‘Pterygium Belt’13

Cameron (1983)1 finds it most prevalent inside the 30th latitude parallel and very rare north or south of 40th parallel.Dimitry (1935)2 has shown similar geographic prevalence in the United States where Pterygium is common in southern cities.Darrel and Bachrachs (1963) United States study shows higher incidence of Pterygium in Veterans living south of the 37th latitude compared to those living in the north.Prevalence: Moram and Hollows (1984)4 found aboriginal and non-aboriginal Australian women to have lower prevalence than their male counterparts.Detels and Dhir (1967)5 found a higher prevalence of Pterygium in indoor saw mill Workers of British, Columbia when compared to outdoor farms of India, Punjab region.

6

Zauberman (1967)6 found that the highly aggressive and recurrent Pterygium or management may be affected by the age of the patient.Risk factors of Pterygium:Dr.Sabir Kamal (1970)7 of Egypt, the nasal part of the bulbar conjunctiva is more affected than the temporal part.Age:Duke and Elder reports congenital Pterygium.Disease affects mostly adults between ages of 25-40 years.Sex: Duke and Elder: more common in males than females with a ratio of incidence 2: 1.Occupation:Commonly seen among farmers, fishermen and stone cutters, Welders.Beattle (1947) found association between blood group O and Pterygium.Etiopathogenesis of Pterygium: Radiation damage by UV rays is widely accepted theory.Both blue and ultraviolet light have been implicated in its causation, as demonstrated in watermen39.

New theories include the possibility of damage to limbal stem cells by ultraviolet40.

Pinkerton et al. (1984)8 found IgE (100%) and IgG (73%) deposited in pterygium connective tissue stroma.Zehender (1869) gave the opinion that pterygium developed from pingecula, this view was also advocated by Fuchs, Parson’s and Arlt.Sugar (1949)9 advocates that pterygium develops from pingecula.Boeckann stressed the importance of the subconjunctival tissue as a factor in the establishment of the pterygium.Friede felt that chronic conjunctivitis is the predisposing factor.Nicholas Dushku et al (1999)10 study data support the theory that increased p53 expression in the limbal epithelia of pingeculae, pterygium and limbal tumors, indicates the probable existence of p53 mutations in these cells as an

7

early event in the development, which is consistent with UV irradiation causation.Donald TH, et al (2001)11 demonstrated in pterygium specimen, apoptotic cells that were found manly confined to the basal layer of cells of the epithelial layer situated immediately adjacent to the fibrovascular support layer. These cells were shown to express significant levels of p53 and apoptosis inhibiting protein bcl-2.Human Papillomavirus in Pterygium: Gallagher et al (2001)12 found that HPV involved in the pathogenesis of primary and recurrent pterygium.Cameron (1983)1 indicated that pterygium occur more commonly where UV light intensity is highest.Surgical management of Pterygium: Avulsion technique: This method was described by Zolli (1979)15 Excision with simple closure of the wound: This method was described by Von-Arlt16 Simple excision or Bare Sclera technique: This method was described by D’ombrain (1948)17

Transplantation operation or McReynold’s operation: To prevent the regrowth

of the pterygium onto the cornea, the head of the pterygium is dissected from the

cornea and transplanted into one of the fornices and sutured there.

Z-Plasty: This method was described by Wilson & Bourne (1988)18 this

procedure allows for the combine removal of pathology tissue from the

cornea and rotation of a flap of more normal conjunctiva into the resulting

defect.

Conjunctival Flaps and Grafts:

Sliding or Advancement Flaps: Introduced by McCoombe and co-workers16

Free graft: Here the Conjunctival tissue is obtained from the same or fellow eye,

care taken to transplant the epithelium with its substantia propria but without

Tenon’s capsule. The capsules contractile force would cause graft retraction.

8

This technique introduced by Kenyon and colleagues (1985)19 showed a recurrence

rate of 5.3%.

Conjunctival autografts are reportedly safe and effective in treating

pterygium35-38

Conjunctival autograft prevents remigration of actinically altered cells onto the

cornea39-41

In a study by Jennifer Forbes et al (1998)20 split thickness buccal mucosal grafts

combined with beta-radiation showed no recurrence.

Transposition Flaps advocated by Smith16 for treatment of recurrent pterygium.

Shimazaki et al (2003)21

reported that amniotic membrane transplantation with

limbal Conjunctival autograft resulted in a recurrence rate of 20% as compared to

amniotic membrane transplantation with conjunctival autograft alone resulted in a

recurrence rate of 8.3%.

Cut and paste technique introduced by Koranyi G et al (2004)22 showed a

recurrence rate of 14%.

Zauberman (1967)6 feels that the rate of recurrence may reflect the above

parameters more than the nature of any surgery procedures.

Tarr and constable (1980)23: reported delayed sclera necrosis and ulceration, which

led to pseudomonas endophthalmitis and evisceration.

Various studies in the literature:

Lewallen S (1989)24 in a study of 19 patients with conjunctival autografting and 16

patients with bare sclera excision found a recurrence rate of 21% with grafting as

compared to 37% with simple excision after a follow up of 14 months.

9

Singh G, et al (1993)25 concluded in a study of 48 patients for 7-21 months

concluded that placebo treated pterygia showed 73% recurrence rate compared to

6.6% with conjunctival autograft technique and 1.7% with Mitomycin-C.

Riordan-Eva P, et al (1993)26 concluded in a study of 108 patients with a mean

follow up of 36 months, with primary pterygium found a recurrence rate of 70%

with bare sclera excision compared to 14% with conjunctival autograft. With

recurrent pterygium a recurrence rate of 82% was found with bare sclera excision

compared to 71% with conjunctival autograft.

Schrage et al (1993)27

in a study of 33 patients with bare sclera excision technique,

40 patients with conjunctival suture and 31 patients with conjunctival autograft

technique found a recurrence rate of 66.7% with simple excision, 58.5% with

conjunctival closure and 32.3% with conjunctival autograft after a mean follow up

of 2-73 months.

Chen P, et al (1995)28

concluded that recurrence rate after Mitomycin-c and

conjunctival autograft was 38% and 39% respectively after mean follow up of 12.3

and 13.5 months. The recurrence rate after Mitomycin treatment wad 18% after

mean follow up of 9.3 months.

Hille k, et al (1996)29

in a study of 21 eyes with bare Sclera technique and 34 eyes

with conjunctival autograft technique with a follow up of 14 months found a

recurrence rate of 35.5% with Bare sclera Technique compared to no recurrence )%

with conjunctival Autograft Technique.

Tan DH, et al (1997)30

concluded that with primary pterygium (mean follow up

15.1), 38 (61%) of the 62 cases of Bare Sclera Excision recurred in contrast to

1(2%) of the 61 cases with Conjunctival Autograft. and with recurrent pterygium

10

(mean follow up 13.2 month), 14 (82%) of the 17 cases in Bare Sclera group had

recurrence as compared to no recurrence in Conjunctival Autograft group.

Figueiredo RS, et al (1997)31

in a study of 31 patients with Bare Sclera Excision

and 40 patients with Conjunctival Autograft Technique found a recurrence rate of

40% and 16% respectively after a follow up of 1 year.

Sanchez-Thorin JC, et al (1998)32 concluded that odds for pterygium recurrence

following surgical treatment of primary pterygium are close to six and twenty five

times higher if no conjunctival autograft placement is performed or if no

intraoperative Mitomycin-C is used respectively.

Kammoun B et al (2001)33 concluded in a study of 167 patients with 151 eyes with

primary pterygium and 16 eyes with recurrent pterygium found a recurrence rate of

55.9% with Bare Sclera Excision, 11.15 in pterygium excision with conjunctival

Autograft and 10.3% in pterygium excision with Mitomycin-C.

Kmihe et al (2001)34 in a study of 30 cases of primary pterygium and 22 cases of

recurrent pterygium found a recurrence rate of 55.9% with Bare Sclera Excision

technique compared to 10% with Conjunctival Autograft Technique after a follow

up of 14 months.

APPENDIX-IC

6.3 OBJECTIVES OF THE STUDY

11

1. The purpose of this study is to investigate the rate of post-oper-ative recurrence of Pterygium after resection using Conjunctival Autograft Technique.

2. To evaluate the change in post-operative best corrected visual acuity.

3. To assess Post-operative cosmetic appearance

APPENDIX-II

7. MATERIAL AND METHODS

APPENDIX-IIA

7.1 SOURCE OF DATA

The data for the study intended is to be collected from patients who have progressive/recurrent pterygium, who visit the Department of Ophthalmology Sri Adichunchanagiri Hospital and Research Centre, B.G Nagara, Nagamangala Taluk, Mandya District and also when we visit the surrounding areas during health check up camps and also during exclusive eye camp. The study will be conducted after obtaining their consent.

12

APPENDIX-IIB

7.2 METHODS OF COLLECTION OF DATA

My intended study is a prospective study carried out on 30 patients visiting the OPD/IPD Coming to the Department of Ophthalmology, Sri Adichunchanagiri Hospital and Research centre for a period of 18 months.

Patient selection will be based on the following criteria.

Patients who has progressive growth of pterygium with ocular irrita-tion and Symptoms related to the growth.

INCLUSION CRITERIA OF STUDY GROUP

Primary Pterygium (Progressive)

Recurrent pterygium

II. EXCLUSION CRITERIA OF STUDY GROUP

Pseudopterygium

Symblepharon

Stationary Pterygium

Atrophic Pterygium

Dry eye patients

13

APPENDIX-IIC

7.3 Does the study require any investigations or interventions to be conducted on patients and other animals? If so describe briefly.

Yes, all patients will have to undergo Routine blood investigations including blood sugar. No other interventions would be conducted on humans/animals.

7.4 Has ethical clearance been obtained from your institution in Case of 7.3?

Yes, Ethical clearance has been obtained from research and dissertation committee / ethical committee of the institution for this study.

APPENDIX-IIC

PROFORMA APPLICATION FOR ETHICS COMMITTEE APPROVAL

SECTION A

a TITLE OF THE STUDYSURGICAL MANAGEMENT OF

PROGRESSIVE/RECURRENT TRUE PTERYGIUM IN RURAL AREAS.

b PRINCIPLE INVESTIGATOR ( NAME AND DESIGNATION )

DR DINESH.PPOST GRADUATE STUDENT IN

OPHTHALMOLOGYA.I.M.S ., B.G.NAGAR

c CO-INVESTIGATOR(NAME AND DESIGNATION)

DR JAYRAM.RM.B.B.S , M.S OPHTHALMOLOGY

PROFESSORDEPARTMENT OF

OPHTHALMOLOGY,SRI ADICHUNCHUNAGIRIINSTITUTE OF MEDICAL

SCIENCES,B.G. NAGARA-571 448

14

d NAME OF COLLABORATING DEPARTMENT /INSTITUTIONS

NOT APPLICABLE

e WHETHER PERMISSION HAS BEEN OBTAINED FROM THE HEADS OF COLLABORATING DEPARTMENT & INSTITUTION

NOT APPLICABLE

SECTION – B

SUMMARY OF THE PROJECT

APPENDIX I SECTION – C

OBJECTIVES OF THE STUDY

SECTION – D

METHODOLOGYAPPENDIX II

A WHERE THE PROPOSED STUDY WILL BE UNDERTAKEN

DEPARTMENT OF OPHTHALMOLOGY

S.A.H & R.C.,B.G.NAGARA

B. DURATION OF THE PROJECT 18 MONTHS FROM NOV 2009

CNATURE OF THE SUBJECT:DOES OF THE STUDY INVOLVE ADULT PATIENTS?DOES THE STUDY INVOLVE CHILDREN?DOES THE STUDY INVOLVE NORMAL VOLUNTEERS?DOES THE STUDY INVOLVE PSYCHIATRIC PATIENTS?DOES THE STUDY INVOLVE PREGNANT WOMEN?

YESNONO

NO

NO

15

D IF THE STUDY INVOLVES HEALTH VOLUNTEERSI. WILL THEY BE INSTITUTE STUDENTS?II. WILL THEY BE INSTITUTE EMPLOYEES?III WILL THEY BE PAID?IV IF THEY ARE TO BE PAID, HOW MUCH PER SESSION?

NONONONO

E IS THE STUDY A PART OF MULTI CENTRAL TRIAL?

NO

F IF YES, WHO IS THE COORDINATOR?

(NAME AND DESIGNATION)

HAS THE TRIAL BEEN APPROVED BY THE ETHICS, COMMITTEE OF THE OTHER CENTERS?

IF THE STUDY INVOLVES THE USE OF DRUGS PLEASE INDICATE WHETHER.

I. THE DRUG IS MARKETED IN INDIA FOR THE INDICATION IN WHICH IT WILL BE USED IN THE STUDY.

II, THE DRUG IS MARKETED IN INDIA BUT NOT FOR THE INDICATION IN WHICH IT WILL BE USED IN THE STUDY

III. THE DRUG IS ONLY USED FOR EXPERIMENTAL USE IN HUMANS.

IV. CLEARANCE OF THE DRUG CONTROLLER OF INDIA HAS BEEN OBTAINED FOR :

USE OF THE DRUG IN HEALTHY VOLUNTEERS

USE OF THE DRUG IN-PATIENTS FOR A NEW INDICATION.

PHASE ONE AND TWO CLINCIAL TRIALS

EXPERIMENTAL USE IN –PATIENTSAND HEALTHY VOLUNTEERS.

NOT APPLICABLE

-

-

NOT APPLICABLE

NOT APPLICABLE

NOT APPLICABLE

NOT APPLICABLE

NOT APPLICABLE

16

G

HOW DO YOU PROPOSE TO OBTAIN THE DRUG TO BE USED IN THE STUDY?

GIFT FROM A DRUG COMPANY HOSPITAL SUPPLIES PATIENTS WILL BE ASKED TO

PURCHASE OTHER SOURCE (EXPLAIN)

NOT APPLICABLE

H FUNDING (IF ANY) FOR THE PROJECT PLEASE STATE

NONE AMOUNT SOURCE TO WHOM PAYABLE

NO

IDOES ANY AGENCY HAVE A VESTED INTEREST IN THE OUT COME OF THE PROJECT?

NO

JWILL DATA RELATING TO SUBJECT/CONTROLS BE STORED IN A COMPUTER?

YES

K WILL THE DATA ANALYSIS BE DONE BY

THE RESEARCHER?

THE FUNDING AGENT

YES

NO

L WILL TECHNICAL /NURSING HELP BE REQUIRED FROM THE STAFF OF HOSPITAL.

IF YES, WILL IT INTERFERE WITH THEIR DUTIES? WILL YOU RECRUIT OTHER STAFF FOR THE DURATION OF THE STUDY?

IF YES GIVE DETAILS OF

I. DESIGNATIONII. QUALIFICATIONIII. NUMBERIV. DURATION OF EMPLOYMENT

NO

NO

NO

NANANANA

17

M

WILL INFORMED CONSENT BE TAKEN? IF YES

WILL IT BE WRITTEN INFORMED CONSENT:

WILL IT BE ORAL CONSENT?

WILL IT BE TAEKN FROM THE SUBJECT THEMSELVES? WILL IT BE FROM THE LEGAL GUARDIAN? IF NO, GIVE REASON :

YES , CONSENT WILL BETAKEN FROM THE PATIENT

N DESCRIBE DESIGN, METHODOLOGY AND TECHNIQUES

APPENDIX II

ETHICAL CLEARANCE HAS BEEN ACCORDED

CHAIRMAN,

DATE: P.G.TRAINING-CUM RESEARCH COMMITTEE, A.I.M.S., B.G.NAGARA

18

APPENDIX-III

LIST OF REFERENCES:

1. Cameron Malcome. Histology of pterygium: An electron microscopic study. Brit J ophthalmology 1983 Sept; 67(9): 604-8.

2. Dimitry TJ. Pterygium geography for United States of America. Eye, Ear, Nose, Throat 1935; 14:45.

3. Darrel RW, Ca Bachrach. Pterygium among veterans. Arch of ophthalmology 1963 Aug; 70(2): 158.

4. Moran DJ, Hollows FC. Pterygium and ultraviolet radiation: A positive correlation. Brit J ophthalmology 1984; 68:343.

5. Detels R, SP Dhir. Pterygium: A geographical study. Arch ophthalmology 1967 Oct; 78(4):485.

6. Zauberman H. Pterygium and its recurrence. Am J ophthalmology 1967 Jun; 63(6):1780.

7. Sabir Kamal. Pterygium Etiopathology and its Treatment. Orient A ophthalmology 1980; 171-175.

8. Pinkerton OD, Yoshitsugi H, Shigrmura BE. Immunological basis for the pathogenesis of pterygium. Am J Ophthalmology 1984; 98:225.

19

9. Sugar HS. A surgical treatment for pterygium based on new concepts to its nature. American Journal of Ophthalmology 1949 July; 32(7):912.

10. Nicholas Dushku et al. Experience and relation to Human Papilloma virus infection in pingecula pterygium and limbal tumors. Arch Ophthalmology 1999; 117:1593-1599.

11. Donald Tan Th, et al. Apoptosis and Apoptosis related gene expression in normal conjunctiva and pterygium. Br J Ophthalmology 2000; 84:212-216.

12. Gallagher MJ, et al. Human Papillomavirus in pterygium. Br J ophthalmology 2001; 85:782-784.

13. Demantini DR, Vastine DW. Pterygium In; Albott Rl, Editor, Surgical Interventions for Corneal and External Diseases, Orlando, USA: Gruno and Straton, 1987 Page: 141.

14. Jose I Barraquer. Etiopathogenesis and treatment of pterygium. Symposium on Medial and Surgical Diseases of Cornea 1980; 533-40.

15. Zolli Christine L. Experience with the Avulsion Technique in Pterygium Surgery. Annuals of Ophthalmology 1979 Oct; 10:1569.

16. Frank A Nesi, Richard D Lisman, Mark R Levine. Smith’s Ophthalmic, plastic and reconstructive surgery. 2nd edition; p1173-1185.

17. D’ombrain. Surgical treatment of pterygium. British J Ophthalmology 1948; 65-71.

18. Wilson Steven E, William M Bourne. Conjunctival Z-Plasty in the treatment of pterygium. American J of Ophthalmology 1988 Sept; 106(3):355-357.

19. Kenyon KR, Wagoner MD. Conjunctival autograft transplantation for advanced and recurrent pterygium. Ophthalmol 1885 Nov; 92(11):1461-70.

20. Jennifer Forbes, et al. Split thickness buccal mucous membrane and Beta-irradiation in the treatment of recurrent pterygium. Br J Ophthalmol 1998; 82:1420-1423.

20

21. Shimazaki Jun, Kosaka Koichi. Amniotic membrane transplantation with conjunctival autograft for recurrent pterygium. Ophthalmology 2003; 110:119-124.

22. Koranyi G, Sexgard S. Cut and Paste: a no suture, Small Incision approach to Pterygium Surgery. Br J Ophthalmol 2004; 88:911-914.

23. Tarr KH. Late complications of pterygium treatment. Brit j Ophthalmol 1980 Jul; 64(7):496-505.

24. Lewallen S. A randomized trial of conjunctival autografting for pterygium in the tropics. Ophthalmology 1989 Nov; 96(11):1612-4.

25. Singh G, Wilson MR. Foster CS. Long term follow-up study of Mitomycin eye drops as adjunctive treatment of pterygium and its complication with conjunctival autograft transplantation. Cornea 1990 Oct; 9(4):331-4.

26. Riordan-Eva P, Kielhorn I, Ficker LA. Conjunctival autografting in the surgical management of pterygium. Eye 1993; 7:634-638.

27. Scharge NF, KUckelkorn R, Joisten M. Surgical therapy of pterygium. Incidence of recurrence after free conjunctival transplant and surgical technique without transplantation. Ophthalmology 1995; 151-160.

28. Chen Philip, Reginald G Ariyasu, venu Kaza. A randomized trial comparing Mitomycin C and conjunctival autograft after excision of primary pterygium. American J of Ophthalmology 1995; 151-160.

29. Hille K, Hoh K, Gross A. Prospective study of surgical therapy of pterygium: Bare Sclera technique Vs Free Conjunctiva-limbus transplant. Ophthalmologe 1996 Jan; 93(3):224-6.

30. Tan DH, Soon-Phaik Chee, Keith BG Dear. Effect of pterygium morphology on pterygium recurrence in a controlled trial comparing conjunctival autografting with Bare Sclera excision. Arch Ophthalmology 1997; 115:1235-1240.

31. Figueiredo RS, Cohen EJ, Gomes JA. Conjunctival autograft for pterygium surgery: how well does it prevent recurrence? Ophthalmic Surgery Lasers 1997 Feb; 28(2):99-104.

32. Sanchez Thorin, Guillermo Rocha, Julie B Yelin. Meta-analysis on the recurrence rates after bare Sclera resection with and without Mitomycin-C use and conjunctival autograft placement in surgery for primary pterygium. British J Ophthalmology 1998; 82:661-665.

33. Kammoun B, Kharrat W, Zouari K. Pterygium: surgical treatment. J.Fr... Ophthalmology 2001 Oct; 24(8):823-8.

21

34. Kmihe N, kamoun B, Trigui A. effectiveness of conjunctival autograft transplantation in pterygium surgery. J Fr Ophthalmology 2001 Sept; 24(7): 729-32.

35. Kenyon KR, Wagoner MD, Hettinger ME, Conjunctival autograft transplantation for advanced and recurrent pterygium. Indian Journal of Ophthalmology Mar 2005 Vol 53 #1.

36. Allan BD, Short P< Crawford GJ, Barett GB, Constable IJ. Pterygium excision with Conjunctival autografting. An effective and safe technique. Br J ophthalmology 1993; 77:698-701.

37. Rao SK, Lekha T, Bickol MN, Sitalakshmi G, Padmanabhan P. Conjunctival-Limbal autograft for primary and recurrent pterygium; technique and results. Indian J ophthalmology 1998; 203-6.

38. Tan DT, Chee SP, Dear KB, Lim AS, Effect of pterygium morphology on pterygium recurrence in a controlled trial comparing conjunctival autografting with Bare Sclera excision. Arch Ophthalmol 1997; 1235-40.

39. Taylor HR, West S, Munoz B et al, The Long term effects of visible light on the eye. Arch Ophthalmol. 1992; 110:99-104.

40. Kwok LS, Coroneo MT. A model for Pterygium formation. Cornea. 1994; 219-24.

22