Pre-Op Assessment of Cataract

1. PRE OP ASSESMENT OF CATARACT

2. OBJECTIVES
 To find visual prognosis
 To exclude ocular or systemic
focus of infection
 To find out the fitness status of
patient for surgery

3. PRE-OPERATIVE ASSESSMENT
 OCULAR HISTORY
 SYSTEMIC HISTORY
 OCULAR EXAMINATION
 OCULAR INVESTIGATIONS
 SYSTEMIC EXAMINATION
 LABOROTARY INVESTIGATIONS

4. OCULAR HISTORY
 Ocular Symptoms Like Blurring Of Vision,coloured Halos,diplopia,glare
 Nuclear Cataract-distant> Near
 Posterior Subcapsular-near>distant
 Duration And Progression
 H/O Of Previous Intraocular Disease
 H/O Previous Cataract Surgery
 H/O Intraocular Injuries

5. SYSTEMIC HISTORY
 H/o of all systemic diseases,current medications patient is on..
 Medications relevant to eye surgery
 Antiplatelets and anticoagulants
 Antihypertensives like diuretics-electrolyte imbalances
 Long term steroids-delayed healing
 Drug allergy to sulfonamides and other antibiotics

6. OCULAR EXAMINATION
Components of Ocular Examination:
• Testing of Visual Acuity
• External Ocular Examination
• Fundus Eamination
• Visual field examination

7. Testing Of Visual Acuity
 Visual acuity - distant (Snellen’s chart)
and near vision (Jaeger’s chart)
 Ocular movements must be tested
 Perception of light must be noted
 Projection of light rays – Test for the function of peripheral retina.
 Potential visual acuity tests – Laser inferometry
& Potential acuity meter test (PAM)

8. External Ocular Examination
 Examination of the head posture, forehead and facial symmetry
 Examination of eyebrows - in cases of ptosis and madarosis
 Examination of the eyelids - position, movements, abnormalities of skin should be
noted
 Examination of Lacrimal apparatus - inspection of
lacrimal sac, lacrimal puncta and lacrimal syringing to locate
any blockage
 Examination of eyeball as a whole - position, visual axes, size and movements to be
noted
 Examination of conjunctiva - for any congestion, scarring, discolouration
 Examination of sclera - for any inflammation, traumatic perforations, etc.
 Examination of cornea - size, curvature, surface,
sheen, transparency, vascularization, sensations,
endotheial status (guttata); Specular microscopy
examination for endothelial cell count and morphology.

9.  Examination of anterior chamber
for the depth and its constituents;
and Intraocular Pressure (IOP) - in
cases of glaucoma and hypotony
 Examination of iris and pupil -
Light reactions and RAPD
(Relative
Afferent Pupilary Defect) should
be checked

10. Examination of Lens
 Cataractous lens should be evaluated for morphology and maturity
of cataract and for grade of nuclear sclerosis
(important for phacoemulsification)
 Other signs to be particularly looked for are: pseudoexfoliation, pigment over
anterior lens capsule and anterior chamber depth.
 Size of lens nucleus and grading of nuclear sclerosis should be determined for
planning size of incision and type of surgery
 Nuclear cataract are harder and need more power with phacoemulsification

11. Fundus Examination
 Retinal and optic nerve function must be assessed preop as if it is defective
operation becomes valueless.
 Pathology such as Retinal Detachment can adversely affect visual
outcome.
 Structure to be assesed during fundus examination: Media, Optic disc,
Macula, retinal blood vessels and genral background
 Hence, a thorough fundus evaluation is important.

12. Visual Field Examination
 Perimetry is the technique used to
asses the visual field of a patient
 Common types of defects in visual
fields are: Altitudinal field defects,
Enlargements of blind spots,
Constriction of peripheral fields,
bitemporal hemianopia, binasal
field defects, etc.

13. Ophthalmic investigations
Retinal/Macular Function
tests
 Two light discrimination test
 Entopic visualization
Projection of Light

14.  Maddox rod test  Colour perception test

15.  Entoptic visualization  Ultrasonic investigation by B-scan
technique

16. INTRAOCULAR PRESSURE
 Should be in each case by APPLANTATION TONOMETRY.
 Management needed in case of inc. IOP

17. REFRACTIVE ERROR
 Its critical to obtain patients pre-operative refractive status in order to
guide IOL implant selection.
 BIOMETRY facilitate calculation of lens power likely to result in desired
post op refractory outcome.
 It involves 1.Keratometry 2.A SCAN
 AXIAL LENGTH-curvature of anterior corneal surface calculation by
interferometry apparatus.
 Use SRK formula (Sanders, Retlaff & Kraff)
 P = A – 2.5L – 0.9K
 P : Power of IOL
 L : Axial length (mm)
 K : Average keratometric reading (Avg. corneal curvature)
 A : Constant specific to the lens implant to be used

18. LAB INVESTIGATIONS
 NORMAL-RBS,ECG,SCREENING,BP
 XRAY,URINE RFT,APTT,PT INR-in patients with individual risk
factors or planned for general anesthesia,
 Preop-antibiotic eye drops QID-3 DAYS PRIOR TO SURGERY
 ANTIANXIETY DRUGS if patient is apprehensive
 Preparing eye-cutting lashes
 Asked to take a normal meal,normal sleep, normal bath,continue
systemic medications .

19. INFORMED WRITTEN CONSENT
 Patient should give full informed written consent before cataract
surgery.
 1 in 1000-achieves very little or no sight
 1 in 10000-lose eye completely
 Mild complications-periocular echymosis,raised IOP,mild iridocyclitis,
wound leak.
 Moderate-posterior capsular rupture, zonular dehiscence, corneal
decompensation,CME,RD(1%)
 SEVERE ENDOPTHALMITIS(0.1%) SUPRACHOROIDAL
HEMORRHAGE

20. THANK YOU