Transcript Dr Grace Nguyo Prorposal - Department of Ophthalmology

PATTERN AND OUTCOME OF
POSTERIOR SEGMENT INJURIES AFTER
OCULAR TRAUMA AT VITREORETINAL
UNIT IN KIKUYU EYE HOSPITAL
Principal Investigator :Dr. Grace Nguyo
Supervisors:
Dr. Muchai Gachago
Dr. Njuguna Margaret
Dr. Jafferji Shafiq
Introduction
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Ocular Trauma is injury to eye from mechanical trauma, chemical injury or radiation.1
Mechanical trauma the usual cause of trauma in post segment.
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Posterior segment are injuries of:
Choroid
Vitreous
Retina and its blood vessels
Optic disc
IOFB in posterior segment
Can be a result of direct or indirect trauma
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Blunt and penetrating injuries are causes of above injuries, blunt having better outcomes. 2
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Posterior segment injuries carry a less favourable prognosis.2
1.bmj.com. Last accessed 25/05/2015
2. Sukati VN, Hansraj R. A retrospective analysis of eye injuries in rural KwaZulu-Natal , South Africa. 2012;71(4):86-94
Introduction
• The Birmingham Eye Trauma Terminology
(BETT) is used to define various eye injuries.3
• Ocular Trauma Score (OTS) is used to predict
final visual outcome.4
3. Kuhn F, Morris R, Witherspoon CD, Mester V. The Birmingham Eye Trauma Terminology system (BETT). J Fr Ophtalmol. 2004 Feb;27(2):206–10
4. Blanco Hernandez RMD LGV. Ocular trauma score at the initial evaluation of ocular trauma. Docstoc.com 2010;(78):209–13.
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Epidemiology
• 1.6 million people blind from eye injuries.5
• In Kenya,2% of all ocular morbidity.6
• In KNH, posterior vitreous, retina and optic nerve
injuries account for 12.7% of all blunt trauma eye
injuries.7
5.bmj.com. Last accessed 25/05/2015
6.National Strategic Plan For Eye Health and Blindness Prevention 2012 to 2018.p30.
7.Kikira S.,Sajabi SM. Ocular complications on blunt non perforating trauma in KNH: University of Nairobi MMed Thesis; 1992
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Management
• Observation
• Medical; AntiVGEF, intravitreal antibiotics
• Surgical: PPV, Scleral buckle, cryopexy, laser or a
combination of these.
• Considerations in surgical repair include:
 timing
 presence of infection
 other systemic complications.8
Ruiz- Moreno J.M, Ashok Garg. Clinical Diagnosis and Management of Ocular Trauma.1st ed. Jaypee Brothers Medical Publishers(P) Ltd;2009.p.65
Factors Determining Visual outcomes
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Time interval between injury and visit to the hospital
Macula involvement
Initial visual acuity
Wound location: a more posterior wound having a poor
visual outcome
• Proliferative VitreoRetinopathy
• OTS 9,10
9.Ying Qi F-YZ. Characteristics and visual outcomes of patients hospitalized for ocular trauma in central China: 2006–2011. Int J Ophthalmol 2015 81 162–168.
2015;8(8(1)):162–8
10. Erdurman FC, , Sobaci G, Acikel CH, Ceylan MO, Durukan AH, et al. Anatomical and functional outcomes in contusion injuries of posterior segment. Eye Lond Engl. 2011
Aug;25(8):1050–6.
Outcome after Management
• Functional success: Final visual acuity of ≥ 20/100
(≥6/30) OR postoperative improvement in visual acuity
of two lines on the Snellen Chart
• Anatomic success is defined as eyes with attached
retina and generally clear media,68-70% .11
• Poor visual outcome: visual acuity of <20/100. 12,13
11.Warrasak S, Euswas A, Hongsakorn S. Posterior segment trauma: types of injuries, result of vitreo-retinal surgery and prophylactic broad
encircling scleral buckle. J Med Assoc Thai. 2005;88(12)(88):1916–30.
12. Ersanli D, Sommez M. Management of retinal detachment due to closed globe injury by pars plana vitrectomy with and without scleral
buckling. Retina. 2006;26(1)(January).
13. Erdurman FC, Erdurman FC, Sobaci G, Acikel CH, Ceylan MO, Durukan AH, et al. Anatomical and functional outcomes in
contusion injuries of posterior segment. Eye Lond Engl. 2011 Aug;25(8):1050–6.
Study Rationale
• To provide information on outcome of
posterior segment injuries in a standard
vitreoretinal set up in our country
• No similar studies done in Kenya
• Providing baseline information in the region
for future planning; e.g. equipment, training
etc.
Objectives
• Main Objective: To review the pattern and
outcome of posterior segment injuries after
ocular trauma as seen at the vitreoretinal unit
at Kikuyu Eye Unit
Secondary objectives
• To describe the cause and clinical presentation
of posterior segment injuries
• To describe types of interventions done
• To determine outcomes after intervention
• To describe factors that determine the visual
outcome
Study Design
• Retrospective case series
Study Location
• Kikuyu Eye Unit, part of Presbyterian Church of
East Africa (P.C.E.A) Kikuyu Hospital
• Referral hospital for vitreoretinal surgery for East
African region
• A UON Dept. of Ophthalmology collaborative
centre
• Patient seen 70000-80000/year in the whole eye
unit
• Estimated post segment pts; 5/month,(60/year)
surgical management 2/month
Case Definition
• Patient seen in KEU Vitreoretinal unit with
ocular trauma involving posterior segment
between January 2010 and December 2014.
• Patient must have had a clear ocular media
Exclusion Criteria
• Severe anterior segment injuries limiting
posterior segment examination
• Missing records
Flow of Data
Collection
All Trauma Patients
Posterior segment
OR Posterior and
Anterior segment
trauma patients
Record demographic
and clinical features
Eliminate those
with anterior
segment injury
only OR other
injuries
Management
Intervention
Surgical
Observation
Medical
Outcome in BCVA
at 1 wk,1 mo,6 mo
and at final follow
Main Outcome Measures
• Outcomes (visual acuity and anatomical) of
patients with posterior segment trauma
• Prognostic indicators of outcome
Study Materials
• Patients files from the records department at
KEU
• Theatre lists from KEU
• Self-structured questionnaire
• Excel data entry sheet
Personnel
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Principal investigator
Theatre records in charge at KEU
Records clerk at KEU
Research assistants
Statistician
Sample Size Calculation
n' = sample size with finite population correction,
N = size of the target population = 150
Z = Z statistic for 95% level of confidence = 1.96
P = Estimated proportion of patients who achieved good visual acuity
outcome after intervention= 71% (Erdurman et al, 2011) 13
d= margin of error = 5%
=102 eyes with posterior segment ocular injuries
Data Management and Analysis
• Data entered into Ms Excel
• Statistical Analysis with SPSS version 21.0.
• Descriptive analysis: means/medians and
percentages.
• Determine the frequencies and proportions of
the variables and present in tables and graphs
Data Management and Analysis
• Chi square/ Fisher’s exact to test associations
between the final BCVA visual outcome and
initial VA
• Odds ratios will be calculated for particular
outcomes in the treatment groups
• 95% confidence interval for all tests
Ethical Consideration
• Ethical permission from KNH/UON-ERC
• Permission sought from the administrative heads of
Kikuyu Eye Unit
• Confidentiality:
 Anonymity assured through use of coded questionnaires
 Questionnaire accessible only to the investigators
Study Period
Tasks
Proposal Preparation, Presentation and
Date
January 2015 to June 2015
Department Approval
Submission of Proposal for Ethical Approval
Data Collection
June 2015
September to October 2015
Data Analysis
November 2015
Report Writing
December 2015
Results Presentation
January 2016
Submission of Dissertation
February 2016
Study Period
Expected Study Limitations
• Missing files
• Combined anterior and posterior segment
injuries making studying visual outcome not
entirely due to posterior segment trauma