Con Moshegov

FRANZCO, FRACSCon MoshegovFRANZCO, FRACS

Ophthalmologist

Advances in Cataract Surgery

Cataract is an opacification of the lens

Acanthamoeba infection

The cataract comes out in one whole piece

Limitations of ECCE

• Prolonged surgery time • Trauma leads to inflammation• Suture distortion of cornea • Prolonged convalescence• Restrictions to activity• Necessitates a regional ‘block’ anaesthetic

The cataract is emulsified then sucked out

Phacoemulsification

Phacoemulsification

Phacoemulsification

Phacoemulsification

• Small incision (2.75 to 3.25mm)

• Can be performed without needles

• Takes only minutes

• Less inflammation

• Faster recovery

• Little restriction to activity

Aqualase

Lens liquifaction device• Alcon Infiniti• Also has ultrasonic

phacoemulsification

Aqualase

• 4 microlitre bursts of water• No heat• Soft plastic tip• Advantages:

– No heat at wound, no wound burns– Less endothelial cell disruption– Less risk of posterior capsular rupture

• Disadvantages:– Expensive – Too slow for hard cataracts

6mm

Intraocular lenses (IOLs)

Small incision surgery

• How do you get the IOL in?

Folding and Insertion of a lens

Advances in IOL technology

Acrysof Natural

Contrast Sensitivity is a better test of functional vision than Visual Acuity!

Sinewave contrast sensitivity is the most widely accepted test of contrast sensitivity

Contrast Sensitivity Decreases with Age

Simulated Image Contrast Enhancement by Aspheric Correction

“Aspheric IOLs emulate the young crystalline lens, whose negative spherical aberration tends to compensate positive spherical aberration of the cornea.”

Aspheric IOLs

Night driving problems related to aberrations

• Long straight street • Simulated speed 35 miles/h• High degree of ambient light

• Long straight road • Simulated speed 55 miles/h• Minimum ambient light (low

beam auto headlights)

City Driving Scene Rural Driving Scene

Night Driving Simulator

Target detection and identification

Night Driving Simulation

With Tecnis™ and at 55 mph, patients identify a pedestrian (rural setting/glare) at 486 feet versus 441 feet for the standard IOL (p=0.0011)

Increased reaction time Safer stopping

Perfect Vision

‘Killing two birds at the same time’

Perfect Vision

Short-sightedness

Long-Sightedness

Astigmatism

Refractive errors

• All of these prevent clear vision without the use of glasses.

• Cataract surgery is increasingly used to reduce peoples dependence on glasses

• If not combined with refractive surgery it would be unwise to promise patients the ability to see perfectly well without glasses

Pre op Biometry

Ultrasound

IOL Master: coherence interferometry

Cornea too steep

Secondary LASIK

Reading without glasses

• Aim for myopia in both eyes• Aim for myopia in one eye (monovision)• Multifocal IOL

Accomodating IOLs

Principle of a Refractive Multifocal IOL

Principle of a Diffractive Multifocal IOL

•Addition of refractive lenscauses light to converge totwo points

ReSTOR pseudoaccomodating IOL

Alcon ReSTOR IOL

Alcon ReSTOR IOL

New Intraocular lenses

However: • Still requires careful patient selection• Optimal distance for reading is short• Best for hypermetropes with presbyopia

– Unaided distance acuity < 6/18• Must control astigmatism

Presbyopia

The procedure in practice

• Almost all done on a ‘day only’ basis

• Hospital or day surgery

• (FBC, EUC, ECG, CXR, INR)

• IVI (or oral) sedation

• Topical anaesthesia

The procedure in practice

• Post op visits on day 1, possibly one week and a month

• Topical corticosteroid, antibiotic and possibly a NSAID

• Eye shield at night

• Abstain from swimming and makeup

• Timing of surgery for second eye is variable

Myth

• My cataract was removed with a laser

Myth

• They had to take my eye out to remove the cataract and then they put it back again

Myth

• My aunt’s cataract had to be removed a second time

Conclusion

• Cataract surgery is one of the most commonly performed operations in Australia

• It has a very high success rate• Developments have taken place to make it

even safer, faster, more accurate and, in some cases, able to free people from a dependence on glasses.