RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES

KARNATAKA, BANGALORE.

Annexure-II

PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION

(To be submitted in duplicate)

1. / NAME OF THE CANDIDATE
AND ADDRESS:
(IN BLOCK LETTERS) / DR.NITYA NEPAL,
DEORALI SCHOOL ROAD, DEORALI BAZAR,
GANGTOK, EAST SIKKIM 737102.
2. / NAME OF THE INSTITUTION / Dr.B.R.AMBEDKAR MEDICAL COLLEGE
K.G.HALLI, BANGALORE – 560045
3. / COURSE OF STUDY AND SUBJECT / M.S. OPHTHALMOLOGY
4. / DATE OF ADMISSION / 1ST JUNE,2009
5. / TITLE OF THE TOPIC / COMPARATIVE STUDY OF CORNEAL ASTIGMATISM INDUCED BY EXTRA CAPSULAR CATARACT EXTRACTION AND SMALL INCISION CATARACT SURGERY.
6. / BRIEF RESUME OF INTENDED WORK
Annexure 1:
6.1 NEED FOR STUDY :
Control of post operative astigmatism has become an important challenge in recent years. After a seemingly well performed cataract extraction with intraocular lens implant, high astigmatism can result, leading to patient dissatisfaction because of the delayed rehabilitation and blurred unaided vision. Large size of the incision and corneal distortion due to suture placement are the major determinants of astigmatism. Manual SICS may therefore be the answer to the problems related to high astigmatism.
Manual SICS has evolved as an effective alternative for phacoemulsification in the present times. It is more cost effective and has more benefits than conventional ECCE. The use of smaller incision has the advantage of faster rehabilitation, less astigmatism and better postoperative vision.
Annexure 2:
6.2 REVIEW OF LITERATURE:
Cataract is the main cause of curable blindness worldwide , the incidence being 20 million, with the developing world accounting for three quarters of blindness[1]. Despite 10 to 12 million cataract operations performed globally, cataract blindness is still thought to be increasing by 1-2 million/year[2]. The transition from intracapsular to extracapsular cataract surgery with posterior chamber IOL implantation has effected a dramatic change in the post operative visual outcome, quality of life and increased acceptance of surgical intervention by the community.
The main objective in modern cataract surgery is to achieve a better unaided visual acquity with rapid post surgical recovery and minimal surgery related complications. Early visual rehabilitation and better unaided vision can be achieved only by reducing the incision size[3]. The size of incision in turn depends on mode of nucleus delivery and type of intra ocular lens (rigid or foldable). In standard extracapsular cataract extraction, the incision needs to be 10-12mm for safe delivery of the nucleus. In manual small incision cataract surgery, it is between 5.5-7mm. The use of smaller incisions have advantages of faster rehabilitation and less astigmatism. This has led to SICS becoming the preferred technique.
Manual SICS has evolved as an effective alternative to phacoemulsification in the present times . It has been proved that manual SICS is more cost effective and has more benefits than conventional ECCE[4].
To list few of them:
·  Better and early wound stability.
·  Less post operative inflammation.
·  Can avoid suture and suture related complications (iris prolapsed, suture infiltrate, bleeding)
·  Less post operative visits.
·  Early reduction and stability of surgically induced astigmatism.
·  Faster rehabilitation.
Hypermature cataracts with liquefied cortex and hard nuclei can get excellent results with manual SICS. Incidence of intra operative complications like posterior capsule rupture and immediate post operative complications are less common in MSICS compared to ECCE and even phaco.
In an era where advances are linked to expensive innovative technology, it is exciting to witness the evolution of simplified , low cost alternatives. Manual small incision cataract surgery offers the smaller incision size of phacoemulsification and the added advantage of not requiring expensive equipments. MSICS offers all the merits of phacoemulsification with the added advantages of having wider applicability, better safety, with a shorter learning curve and lower cost.
High corneal astigmatism following cataract surgery prevents an aphakic patient from enjoying rapid visual recovery with glasses, contact lenses and intraocular lenses [5] . T here are a large number of variables which contribute to the resultant postoperative astigmatism. The subject has been reviewed by Swinger (1987). Type of suture material and technique of suturing play an important role in causing suture induced astigmatism
With the rule (plus cylinder with axis between 70 0 - 110 0) suture induced astigmatism has been reported following the use of 10 o monofilament nylon suture for wound closure in cataract surgery[7,8,9] The astigmatism adversely affects the quality of visual acuity with glasses, contact lenses or intraocular lenses, besides giving aesthenopic symptoms to the patient [10]. Many operative and post operative (suture cutting) methods have been used to minimize postoperative astigmatism. [11,12,13,14]
Variable and unpredictable astigmatism has resulted with the use of intraoperative keratometry [15,16]
Studies show a significant difference in the amount of induced corneal astigmatism between ECCE and SICS .
Published evidence points out that surgically induced astigmatism following ECCE is
3.91 times higher than MSICS.
In ECCE 72.2% suffered from with the rule astigmatism and 20% against the rule astigmatism and 7.8% remained neutral following surgery. Whereas in SICS, 40% suffered from with the rule astigmatism, 40% against the rule astigmatism and 20% were neutral.
The amount of Surgically induced astigmatism , decreases over a period of time.
The final induced postoperative astigmatism has been seen to be 1.46+ 0.83 D for patients with ECCE and 2.68+ 1.9 D for patients with SICS, a highly significant difference (p < 0.004).[19]
Astigmatism prevention and control is one of the biggest challenges for a surgeon after cataract surgery. The major determinants of astigmatism are the site and size of the incision, the type of suture used, and the suturing technique.
Since postoperative astigmatism is the major determinant of visual outcome, a comparative study is essential to ascertain the difference in induced astigmatism, if any, for conventional ECCE versus small incision surgery.
Annexure 3:
6.3 OBJECTIVES OF THE STUDY :
Ø  To study and compare the incidence, magnitude, type and course of corneal astigmatism in conventional ECCE and manual SICS .
Ø  To study relationship between preoperative and post operative corneal astigmatism.
Ø  Determine corneal astigmatism due to various types of incisions in SICS.
Annexure 4:
MATERIALS AND METHODS.
7.1 Source of Data:
Patients visiting Dr.B.R.Ambedkar Medical College hospital out patient and inpatient departments, those who have undergone Cataract surgery (ECCE and SICS).
Study will be for duration of two years.
7.2. Methodology of Collection of Data:
All patients with cataract surgery will be subjected to the following:
1) Visual Acuity using Snellen’s distant vision chart and Jager’s near vision chart.
2) Refraction done by retinoscopy , skiascopy and streak retinoscopy.
3) Keratometry.
4) A-Scan.
All the findings will be recorded in the data.
Written informed consent will be taken from all the patients involved in the study.
Sample size:
. Minimum of 50 patients with cataract surgery will be examined for the study.
(ECCE = 25, SICS = 25)
Inclusion criteria:
Ø  Patients aged more than 18years.
Ø  Patients operated for cataract (ECCE or SICS).
Ø  Patients will be selected irrespective of the sex.
Exclusion Criteria:
Ø  Age less than 18years (Paediatric age group).
Ø  Patients with coexisting glaucoma .
Ø  Uveitis
Ø  Subluxated lens
Ø  Posterior segment pathology
Ø  Aphakic patients.
Ø  Keratoconus.
Ø  Corneal pathology.
Ø  Connective tissue disorders.
Ø  One eyed patients.
7.3 Does the study require any interventions or investigations to be conducted on patients or other humans or animals ?
Yes.
These investigations are routine and patients will not have to bare any additional expenditure.
7.4 Has ethical clearance been obtained from your institution?
Yes.
Annexure 5:
LIST OF REFERENCES :
1.  Thylefors B, Negrel AD, Parsrajasegaram R, et al. Global data on blindness: an update. Bull World Health Organ 1995;73:115-21.
2.  WHO, Global initiative for the elimination of avoidable blindness. Geneva: WHO, WHO/PBL/97.61
3.  Limburg H, Vasavada A, MazumdarG et al. Rapid assessment of cataract blindness in urban district of Gujrat. Indian J Ophthalmology 1999;47:135-41.
4.  Gogate PM, Deshpande M, Wormald RP, Is manual small incision cataract surgery affordable in the developing countries? A cost comparison with extracapsular cataract extraction. Br J Ophthalmology,2003; 87(7):843-6.
5.  Roper Hall MJ “Type of cataract extraction” Stellart’s eye Surgery 7th Edition. 1989:286-328.
6.  American Academy Of Ophthalmology, 2001-2002, 90-95.
7.  Kathryn A “Theory of wound construction for cataract surgery” fundamentals and principles.
8.  Wound healing of conjunctiva, cornea, sclera: American academy of ophthalmology , 2002:353-355:AAO-Wilhelmus KR.
9. / Kratz RP, Johnson SH. Clinical results with surgical keratometer. Int Ophthalmol Clin 1983,23(4):87-99
10. / Swinger CA. Postoperative astigmatism, Surv Ophthalmol 1987,31:219-248
11. Van Rij G, Waring GO Ill. Changes in corneal curvature induced by sutures and incisions. Am J Ophthalmol 1984,98:773-83

12. Rowan PJ. Corneal astigmatism following cataract extraction. Ann Ophthalmology 1978,10:231-234
13. Wishart MS, Wishart PK, Gregor ZJ. Corneal astigmatism following cataract extraction. Br J Ophthalmol 1986,70:825-30
14. Stainer GA, Binders PS, Packer WT, Perl T. The natural and modified course of pot cataract astigmatism. Ophthalmic Surgery 1982, 13:822-827
15. Jaffe NS. Postoperative corneal astigmatism. In cataract surgery and its complications. 4th ed St Louis CV Mosby Company 1984:111-127
16. Troutman RC, Keilly S, Kaye D, Clahane AC. The use and preliminary results of Troutman surgical keratometer in cataract and corneal surgery. Ophthalmology 1977,83:232238
17. Colvar DM, Kratz RP, Mazzocco TR, Davidson B. Clinical evaluation of the Terry surgical keratometer. J Am Intraocular Implant Soc 1980,6:249-251

18. Colvard DM, Kratze RP, Mazzocco TR, Davidson B. The Terry surgical keratometer : a 12 month follow up report. J Am Intraocular Implant Soc 1981,70:348-50
19. Asian journal of Ophthalmology, Volume 4, Number 4,2002.
9. / SIGNATURE OF THE CANDIDATE
10. / REMARKS OF THE GUIDE
11. / NAME & DESIGNATION OF THE GUIDE

SIGNATURE
CO-GUIDE (IF ANY)
SIGNATURE
HEAD OF THE DEPARTMENT

SIGNATURE / DR.RANISUJATHA, M.B.B.S, DOMS,M.S
PROFESSOR & HEAD-DEPT OF OPHTHAMOLOGY
DR.RANISUJATHA, M.B.B.S, DOMS, MS.
PROFESSOR & HEAD OF THE DEPARTMENT, OPHTHAMOLOGY,
DR.B.R.AMBEDKAR MEDICAL COLLEGE, BANGALORE - 45.