RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES, KARNATAKA BANGALORE
ANNEXURE-II
PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION
1) Name of candidate: Dr KIRTHI RAJ
Permante Address : S/o N.RAJANNA
No,19 HEERACHAND ROAD
COX TOWN BANGALORE- 560005
2) Name of Institution: kempegowda institute of
medical College
V.V.PURAM, Bangalore-560070
3) Course of study and subjects : M.S. OPHTHALMOLOGY
4) Date of admission to the course: May 10, 2010
5) Title of Topic :
A Prospective study to assess the role of superior and temporal scleral incision in surgically induced cornea astigmatism among patients undergoing manual small incision cataract surgery.
6 Brief Resume of the intended work
6.1 Need for the study:
In the past, the main goal of cataract surgery was to remove the cataract & implant intraocular lens (IOL) that would give the patients reasonably good unaided vision post-operatively. Modern technology however enables us to calculate the IOL needed for the specific patients with more accuracy and small incision cataract surgery gives surgeons today the ability to do surgery in less time greater accuracy & less complication post-operatively.
One of the greatest hurdles in modern cataract surgery is surgically induced astigmatism (SIA).
In early childhood cornea is steep with against the rule astigmatism being the most common axis and throughout childhood & adolescence astigmatism with the rule develops and as the age advances cornea steepens (more in the horizontal meridian) and shift in corneal astigmatism axis towards against the rule astigmatism being more common [1] With the rule astigmatism induced by temporal incision is advantageous because most elderly cataract patients have preoperative against the rule astigmatism [2] which worsens the preexisting astigmatism when the incision is taken superior. The same is minimized and well controlled when incision is made temporally. Hence there is need of a study of superior versus temporal scleral incision in manual small incision cataract surgery to reduce post operative astigmatism for good post operative visual recovery
6.2 Review of Literature
1) Two randomized controlled trails in, Pune, India, had found MSICS to be more effective and economical than ECCE and almost as effective as and more economical than phacoemulsification [3]
2) Study done by S.S Haldipurkar et al revealed that temporal incision is farthest from the visual axis & any flattening is less likely to affect the corneal curvature at the visual axis. When the incision is located superiorly, gravity & eyelid blink create a drag on the incision. These forces are neutralized with temporal incision; because it is parallel to the vector of the forces. Superior temporal incision also free from the effect of gravity &eyelid pressure & tends to induce less astigmatism. The amount of astigmatism induced by different type of incision in a series of 64 cases were as follows
• Superior temporal incision -----0.8D
• Superior sclera incision------1.2D [2]
3) Studies done in Mumbai where they compared superior, superior-temporal and temporal in manual SICS on 45 eyes have shown that mean astigmatism induced by surgery was 1.28Dx2.9Ddegree for superior incision,0.2x23.7degree for superotemporal incision &0.37x90degree for temporal incision .The study found that induced astigmatism was lower in temporal & superior-temporal groups compared to that in the superior groups [4]
4) Small incision surgery does not systemically degrade the optical quality of the anterior corneal surface. However it introduces changes in some aberrations especially in non- rotationally symmetric terms such as astigmatism, coma & trefoil. The incision site plays a main role in the corneal changes after surgery [5]
5) Study done in Bangladesh showed SICS with a temporal approach provides earlier stabilization of refraction and of visual acuity with minimal surgically induced astigmatism in comparison to SICS with a conventional superior approach. The preoperative and postoperative complications are similar in both the approaches. Temporal SICS is as safe as superior approach SICS and this technique can be used as an alternative to temporal clear corneal phacoemulsification particularly in hard and hyper mature cataracts [6]
6.3 OBJECTIVES OF STUDY:
• To analyze the surgical induced corneal astigmatism by superior & temporal scleral incision in manual small incision cataract surgery.
• Visual outcome in small incision cataract surgery.
• To compare other merits/demerit of superior and temporal scleral incision.
7 Materials and Methods 7.1 Source of Data Patients of age 40 yrs and above with senile cataract
admitted to ophthalmic wards in KEMPEGOWDA INSTITUTE OF MEDICAL SCIENCES .
7.2 METHODS OF COLLECTION OF DATA
(Including sampling procedure, if any)
STUDY DESIGN: One year Prospective, comparative and randomized study
SAMPLE SIZE : 60(30 PATIENTS IN EACH GROUP)
DURATION : 1 YEAR
• Each case will be examined with detailed history, regarding their complaints, the onset and duration of symptom
• Pre-operative visual acuity recording, retinoscopy, slit lamp examination keratometry, biometry will be done and recording of preexisting astigmatism, IOP measurement& calculation of IOL power by SRK –II formula .Fundus examination will be carried out .
• After obtaining written consent patient will be subjected to manual small incision cataract surgery under peribulbar block(PBB) local anesthesia (LA) by randomly dividing into two groups with posterior chamber intraocular lens ( PCIOL) implantation. In the series comparative analysis of per operative & post operative pattern of astigmatism studied.
• During follow up assessment of operation:
• Visual acuity will be taken
• Anterior segment examination with slit lamp bio microscope
• Retinoscopy
• Keratometry by HRK 7000 ver 3.02.01B auto Ref/keratometer
• Fundoscopy (direct/ indirect) will be studied & recorded
•Patients will be followed on the 1st day, 2nd week, 4th week and 6th week [6] .All the above mentioned examination will be repeated.
•The resultant astigmatism will be calculated by Retinoscopy, K1 &K2 with pre operative values .The magnitude of astigmatism is calculated by vector analysis [7] with aid of surgically induced astigmatism calculator free software[4].
STATISTICAL ANALYSIS:
Descriptive statistics like percentage, mean, standard deviation will be applied and other relevant inferential statics will be used.
INCLUSION CRITERIA:
All patients of age 40 years & above of either sex with senile mature & immature cataract who will be screened at ophthalmology opd and admitted to ophthalmology wards at KEMPEGOWDA INSTITUTE OF MEDICAL SCIENCES
EXCLUSION CRITERIA:
• Patients with congenital & developmental cataract
• Patients with complicated cataract
• Patients with preexisting corneal opacity, uveitis, glaucoma
& macular degeneration which independently cause limitation of vision
• Patients with ocular surface disorders
• Posterior segment complication
• Preexisting Corneal Ectasia
• Long standing systemic illness
• Systemic diseases which effects the corneal hysteresis
7.3. Minimum investigation like
• Blood for Hb%
• Complete haemogram
• Urine routine
• HIV& HBsAg
Ophthalmic Examination will include:
• Detailed History
• Pre operative Visual acuity, Retinoscopy
• Slit lamp examination
• Fundus examination
• IOP measurement using I care (Rebound tonometry)
• Patency of lacrimal passage
• Keratometry reading using
HRK 7000 ver 3.02.01B aut Ref/keratometer & B&L
• Axial length measured by A scan biometrics
• Power of PCIOL is calculated by using SRK-II formula
ETHICAL CLERANCE:
Yes. Ethical clearance has been obtained from ethical committee, Kempegowda Institute of Medical Sciences, Bangalore-560070
8.LIST OF REFRENCES:
1. Read SA,Collins MJ,Carney LG.A review of astigmatism and its possible genesis.Clin Exp Optom 2007;90:1:5-19
2. S.S Haldipurkar,Hasanain T Shikari ,Vishwanath Gokhale, Wound construction in manual small incision cataract surgery. Indian J ophthalmol:2009;57:9-13
3. Parikshit M Gogate Small incision cataract surgery: Complications and mini-review Indian J Ophthalmol: 2009; 57:45-9
4. Gokhale NS .Sawhney S .Reduction in Astigmatism in Manual Small Incision Cataract surgery through Change Of Incision Site. Indian J Ophthalmol 2005; 53:201-203
5. Antonio Guirao et al, Corneal Aberrations before and after Small-Incision Cataract Surgery .Invest Ophthalmol Vis Sci 2004; 45:4312-4319 DOI:10.1167/iovs.04-0693
6. Md.Harun-Ur-Rashid et al, Non-Phaco Small Incision Suture less Cataract Surgery: A Compartitive Study Between Temporal And Conventional Superior Scleral Tunnel Approach Journal of Bangladesh Academy Of Ophthalmology,July,2002;Vol-9(2):(29-37)
7. Alpins AN,Goggin M.Practical Astigmatism Analysis For Refractive Outcomes in Cataract and Refractive Surgery.Surv Ophthalmol 2004;49(1):109-122
9 Signature of Candidate: *
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10 Remarks of Guide:
High astigmatism is an important cause of poor uncorrected visual acuity after cataract surgery. Pre Existing against the rule astigmatism in elderly patients is corrected through temporal scleral tunnel but the same gets aggravated in superior incision. The objectives of the study are to evaluate the amount of surgical induced astigmatism in temporal and superior - scleral incision. Temporal is also indicated with patients with deep sockets, in patients with filtering bleb, scleral thinning etc. Hence, this study taken by the candidate helps in knowing the amount of surgically induced astigmatism in manual small incision cataract surgery and also to compare surgically induced astigmatism in temporal and superior scleral incision
11 11.1 Name and Designation of the (In BLOCK Letters)
Guide : Dr. R.S UMA DEVI (M.S Ophthalmology)
Associate Professor
Dept of Ophthalmology
KEMPEGOWDA INSTITUTE OF MEDICAL SCIENCES COLLEGE BANGALORE
11.2 Signature : *
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11.3 Co - Guide (If any):
11.4 Signature *
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11.5 Head of department
Dr. N.V.V HIMANSHU
(M.S.Ophthalmology)
Professor and Head -Dept. of Ophthalmology
KEMPEGOWDA INSTITUTE OF MEDICAL SCIENCES COLLEGE, BANGALORE
11.6 Signature *
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12 12.1 Remarks of the Chairman and Principal
12.2 Signature *
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