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Contents

Section 1

Section 2

Section 3

Section 4

Section 5

Section 6

Section 7

Subjects Index

Help ?

NO ANESTHESIA CATARACT / CLEAR LENS EXTRACTION

Chapter 42

NO ANESTHESIA CATARACT /

CLEAR LENS EXTRACTION

Athiya Agarwal, M.D., Sunita Agarwal, M.S., Amar Agarwal, M.S.

 

Note from the Editor in Chief: Chapters 42

technique,

surgeons throughout the

world have been

and 43 are presented in this Volume because both

attempting to make this new procedure

safer and

 

are focused toward the use of this technique for pur-

easier

to perform while assuring good visual

poses of correction of

high refractive errors.

outcome

and patient recovery.The fundamental goal

Contents

 

 

 

 

 

 

 

 

of Phaco is to remove

the cataract

with minimal

Introduction

 

 

 

 

 

disturbance to the eye using least

number of surgical

Section 1

 

 

 

 

 

 

 

 

 

 

 

 

 

 

manipulations. Each maneuver should be performed

Section 2

 

On

 

th

 

 

 

 

with minimal force and maximal efficiency should

 

 

June 13 1998 at Ahmedabad, India the

be obtained.

 

 

 

 

 

 

 

Section 3

first

No-anesthesia cataract

surgery was

done by

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

the authors (Amar Agarwal) at the

Phako

&

The

latest

generation

Phaco proceduresSection 4

Refractive

Surgery

conferenceThis. was performed

began

with

.HowardDr Gimbel’s

“divide and

 

conquer” nuclear

fracture

technique

in which he Section 5

as

a livegerysur in front of 250 delegates. This has

simply split apart the

nuclear rim. Since then we

 

opened up various new concepts

in cataract

Section 6

surgery (1). In this surgery the

technique

of karate have evolved

through

the

various techniques

chop was used.

 

 

 

 

 

namely four

quadrant cracking, chip and flip, spring

Section 7

 

 

 

 

 

surgery, stop and chop and phaco chop.

 

 

For

high

refractive

errors,

clear lens

 

 

 

 

Clear lens removal by phacoemulsification

Subjects Index

extraction with phacoemulsification is a very good

 

is a very good alternative to manage refractive errors.

 

alternative. In such cases, if necessary one can implant

 

In these cases, as the nucleus is soft one can use only

 

an IOL or leave the patient aphakic if the myopia is

 

phacoaspiration to remove the nuclei, rather than

 

very high & does not warrant an IOL. This technique

 

use ultrasound power.

 

 

 

 

 

 

is very useful in hypermetropes, as Lasik does not

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

give excellent results in such cases. The most

 

 

 

 

 

 

 

 

 

 

commonly done refractive surgery in the world is

Karate Chop

 

 

 

 

 

Help ?

not PRK or LASIK, it is cataract surgery. This is

 

 

 

 

 

 

 

 

 

 

 

why this chapter will discuss phacoemsulification

 

Unlike the peripheral chopping of Nagahara

 

techniques for removal of cataract as well as clear

 

 

or other stop and chop techniques

we have developed

 

lens extraction.

 

 

 

 

 

 

 

 

 

 

 

a safer technique

called ”CentralAnterior chopping”

 

 

 

 

 

 

 

 

 

 

NUCLEUS REMOVAL

 

 

or “karate chop”. In this method the phaco tip is

 

TECHNIQUES

 

 

 

 

embedded by a single burst of power in the central

 

 

 

 

 

safe zone and after lifting the nucleus a little bit (to

 

 

 

 

 

 

 

 

 

 

 

Since the introduction of Phacoemulsification

lessen the

pressure

on the posterior capsule) the

 

chopper is used to chop

the nucleus. In soft nuclei, it

 

as an

alternative to

standard cataract extractionis very difficult to chop the nucleus. In most cases,

 

LASIK AND BEYOND LASIK

451
452 SECTION VII

Chapter 42

one can take it out in toto. But if the patient is about

If the astigmatism is plus at 90 degrees

then the

 

40 years of age then one might have to chop the

incision is made superiorly. (Read the chapter on

 

nucleus. In such cases we embed the phaco probe in

corneal topography).

 

 

 

 

 

 

 

 

 

 

the nucleus and then with the left hand cut the nucleus

 

First

of all, a needle with viscoelastic is

 

as if we are cutting a piece of cake. This movement

injected inside

 

the eye in the area where the second

 

should be done three times in the same place. This

site is made (Figure 42-1). This will

distend the

eye

will chop the nucleus.

 

 

 

 

 

 

 

so that when you make a clear corneal incision, the

 

 

 

 

 

 

 

 

 

 

 

 

 

eye will be tense and one can create a good valve.

 

Soft Cataracts

 

 

 

 

 

 

 

 

Now use a straight rod to stabilize the eye

 

 

 

 

 

 

 

 

 

 

 

 

 

with the left hand. With the right hand make the clear

 

In

soft cataracts, the technique is a bit

corneal incision (Figure 42-2).

 

 

 

 

 

 

 

 

different.

We

embed the

phaco

tip and then cut the

When we

started making the temporal

 

 

 

 

positioned ourselves temporally.The

 

nucleus as if we are

cutting

a piece of cakeThis.

incisions, we

 

problem by this method is that,

every time

the

should be done 2-3 times in the same area

so that the

 

 

 

 

 

 

 

 

 

 

 

 

microscope has to be turned which in turn would

 

cataract

gets cut. It is very tough to

chop

 

a soft affect the

cables

connected to the video camera.

cataract, so this technique helps in splitting the

Further

the

 

theatre staf

would

get disturbed

cataract.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

between right eye and

left

 

eye. o Tsolve

 

this

Contents

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Agarwal Chopper

 

 

 

 

 

 

problem, we then decided on a different strategy.

 

We

Section 1

 

 

 

 

 

 

have operating trolleys on wheels. The patient is

 

 

 

 

 

 

Section 2

 

 

 

 

 

 

 

 

 

 

 

 

wheeled

inside the operation theatre and for the right

We

have

 

devised our own chopper.The

eye the trolley is placed slightly obliquely so that the

Section 3

other choppers, which cut from the periphery, are

surgeon does not change his or her position. The

 

blunt choppers. Our chopper is

a

sharp chopper.It

surgeon stays at the

12’o’clock

position. For the left Section 4

has a sharp cutting edge. It also has a sharp

point.

eye the trolley with the patient is rotated horizontally

Section 5

The advantage

of

 

 

 

 

 

 

 

so that the temporal portion of the left eye comes

at

such a chopper is that you can

 

 

 

 

 

 

 

 

 

 

 

 

 

 

chop in

the center and need not go to the periphery.12’o’clock. This way the patient is moved and

 

not

Section 6

In

this method by going directly into the

the surgeon.

 

 

 

 

 

 

 

 

 

 

 

Section 7

center of the

nucleus without any sculpting ultra

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Rhexis

 

 

 

 

 

 

 

 

 

 

 

 

 

sound energy required is reduced. The chopper

 

 

 

 

 

 

 

 

 

 

 

 

Subjects Index

always remains within the rhexis margin and

never

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

goes underneath

the anterior capsule.

Hence it is

 

Capsulorhexis is then performed through the

 

easy to work

with even small pupils or glaucomatous same incision (Figure 42-3).

While performing the

 

eyes. Since we don’t have

to widen

the

pupil,

thererhexis it is important to note

 

that

the rhexis

is

is little

likelihood

of

tearing

the sphincter andstarted from the center and the needle moved

to the

allowing

prostaglandins to leak

out

and

causeright

and then downwardThis. is important

because

 

inflammation or cystoid macular edema. In this

today concepts have changed of temporal and nasal.

Help ?

technique we

can easily

go into even hard nuclei on

It is better to remember it as superior, inferior, right

 

the first attempt.

 

 

 

 

 

 

 

 

or left. If we

would start the rhexis from the center

 

KARATE CHOP TECHNIQUE

 

 

and move it to the left

then the weakest point of the

 

 

 

rhexis is generally

where

you finish

it. In other

 

 

 

 

 

 

 

 

 

 

 

 

words, the point where you tend to lose

the rhexis is

 

Incision

 

 

 

 

 

 

 

 

 

 

near its completion. If you have done the rhexis

from

 

 

 

 

 

 

 

 

 

 

 

 

 

the

center and moved to the left, then you might have

 

Ours

 

is a modification of the Nagahara chop.

an

incomplete

rhexis on the left-hand side either

The important

feature

is that we don’t chop the

inferiorly or

superiorly. Now, the phaco probe is

 

always moved down and

to the

left.

So every stroke

periphery. A temporal clear

corneal section is made.

NO ANESTHESIA CATARACT / CLEAR LENS EXTRACTION

Figure 42-1: Eye with cataract. Needle with viscoelastic entering the eye to inject the viscoelastic. This is the most important step in no anesthesia cataract/clear lens surgery. This gives an

entry into the eye through which a straight rod can be passed to Figure 42-3: Rhexis being done with a needle. stabilize the eye. Note no forceps hold the eye.

Contents

Section 1

Section 2

Section 3

Section 4

Section 5

Section 6

Section 7

Subjects Index

Figure 42-2: Clear corneal incision. Note the straight rod inside the eye in the left hand. The right hand is performing the clear corneal incision. This is a temporal incision and the surgeon is sitting temporally.

of your hand can

extend

the

rhexis posteriorly

 

creating a posterior capsular rupture. Now, if we

 

perform the rhexis from the center and move to the

 

right and then push

the flap inferiorlythen if we

Help ?

have an incomplete rhexis near the end of the rhexis

 

it will be superiorly and to

the

right. Any incomplete

 

rhexis can extend

and

create

a posterior capsular

 

tear. But in this case, the chances of survival are better. This is because we are moving the phaco probe down

and

to the left, but the rhexis is incomplete up and

to

the right.

 

If you are a left handed person, start the

rhexis from the center and move to the left and then down.

LASIK AND BEYOND LASIK

453

Chapter 42

Hydrodissection

Hydrodissection is then performed (Figure 42-4). We watch for the fluid wave to see that hydrodissection is complete. We do not perform hydrodilenation or test for rotation of the nucleus.

Viscoelastic is then introduced before inserting the phaco probe.

Karate Chop - Two Halves

We

then insert the Phaco probe through

the

incision

slightly superior to the center of the nucleus

(Figure 42-5). At that point apply ultrasound and see

that the phaco tip gets embedded in the nucleus (Fi-

gure 42-6). The direction of the phaco probe should

 

be obliquely

downwards

toward the vitreous

and

not horizontally towards

the irisThen. only the

 

nucleus will get

embedded.

The settings at

this

Figure 42-4: Hydrodissection

Contents

Section 1

Section 2

Section 3

Section 4

Section 5

Section 6

Section 7

Subjects Index

Help ?

Figure 42-5: Phaco probe placed at the superior end of the rhexis. Figure 42-6: Phaco probe embedded in the nucleus. We started from the superior end of the rhexis and note it has got embedded in the middle of the nucleus. If we had started in the middle then we would have embedded only inferiorly, that is, at the edge of the rhexis and chopping would be difficult.

454 SECTION VII

 

NO ANESTHESIA CATARACT / CLEAR LENS EXTRACTION

stage are 70% phaco power, 24 ml/minute flow rate

Remember, do not go to the periphery for

and

101 mm of Hg suction. By the time the phaco chopping, but do it at the center.

 

tip

gets embedded in the nucleus the tip would have

Once you have created a crack, split the

reached the middle of the nucleusWe. do not turn

nucleus till the

center.Then rotate the nucleus 180

the bevel of the phaco tip downards when we do this

degrees and crack again so that you get two halves

step, as the embedding is better the other way. We

of the nucleus. In

brown cataracts, the

nucleus will

prefer a 15-degree tip but any tip can be used.

crack but sometimes in the center the

nucleus will

 

Now stop phaco ultrasound and bring your

still be attached. You have to split the nucleus totally

foot to position 2 so that only suction is being used. in two halves and you should see the posterior

Now lift the nucleus. When

we say

lift it does notcapsule throughout.

 

mean lift a lot but just a little

so that when we apply

 

pressure on the nucleus

with the

chopper theKarate Chop - Further Chopping

direction of the pressure is downwards. If the capsule

 

 

is a bit thin like in hypermature cataracts you might

Now that

you have two halves, you have a

rupture the posterior capsule and create a nucleus

shelf to embed

the probe. So, now place the probe

drop. So when we lift the nucleus the pressure on the

with ultrasound into one half of the nucleus

posterior capsule is lessened. Now, with

the chopper

(Figure 42-8). You can pass the direction of the probe

cut the nucleus with a straight downward motion horizontally as now you have a shelf. Embed the

Contents

(Figure 42-7)

and

then move the chopper to the left probe, then pull it

a little bit.This step is important

Section 1

when you

reach

the center

of the nucleus. In otherso that you get

 

 

 

the extra bit of space for chopping.

words, your left hand moves

the chopper like a This will prevent you from

chopping the rhexisSection 2

laterally reversed L.

 

 

margin. Apply the force of the

chopper downwards.

Section 3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Section 4

 

 

 

 

 

 

 

 

 

 

Section 5

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Section 6

 

 

 

 

 

 

 

 

 

 

Section 7

 

 

 

 

 

 

 

 

 

 

Subjects Index

Help ?

Figure 42-7: Left hand chops the nucleus and splits like a later-

Figure 42-8: Phaco probe embedded in one half of the nucleus.

ally reversed L, that is downwards and to the left.

Go horizontally and not vertically as you have now a shelf of

 

nucleus to embed. Chop and then split the nucleus.

LASIK AND BEYOND LASIK

455

Chapter 42

Then move the chopper to the left so that the

nucleus

gets split.Again, you should see posterior capsule

throughout so that you know the nucleus is totally

split.

Then release

the probe, as the probe will still

be embedded into

the nucleus. Like

this create three

quadrants in one

half

of

the nucleus.

Then make

another three halves with the second half

of the

nucleus.Thus, you now have 6 quadrants or pie-

shaped

fragments. The

settings

at

this stage are

50%

phaco

power,

24 ml/minute flow rate and

101 mm of Hg suction.

 

 

 

 

 

Remember 5 words - Embed, Pull, Chop,

Split and Release.

 

 

 

 

Pulse Phaco

 

 

 

 

 

 

 

 

 

 

 

Once all the pieces have been chopped, take

 

 

 

 

 

out each piece one by one

and in pulse phaco mode

 

 

 

 

 

Figure 42-9: Cortical aspiration completed. Note the straight

aspirate the pieces at the level

of the iris. Do not

work in the bag unless the cornea is pre-operatively

rod in the left hand which helps control the movements of the

eye.

bad or the patient is very elderly.The

setting at

this

 

 

 

 

 

stage can be Phaco power 50-30%, flow rate 24

ml

and suction 101 mm of Hg.

 

 

 

 

 

 

 

 

 

 

Rememberit is better to have striae

 

 

 

 

 

 

 

 

 

 

 

keratitis than posterior capsular rupture.

 

 

 

 

 

 

Cortical Washing and

 

 

 

 

 

 

 

 

Foldable IOL Implantation

 

 

 

 

 

 

 

 

The

next step is to do cortical washing

 

 

 

 

 

(Figure 42-9). Always

try

to

remove

the

 

 

subincisional cortex first, as that is the most difficult.

 

 

 

 

 

In

Figure 42-10 note the cortical aspiration

 

 

complete. Note

also the rhexis margins. Note also

 

 

 

 

 

that everytime the

left hand

has the straight rod

 

 

 

 

 

controlling the movements of the

eye. If necessary

 

 

 

 

 

use a bimanual irrigation aspiration technique. Then

 

 

 

 

 

inject viscoelastic and implant the foldable IOL. We

 

 

 

 

 

use

the plate

haptic foldable IOL(Figure 42-11)

 

 

 

 

 

with large

fenestration’ generally as

we find them

 

 

 

 

 

superior. Take out

the viscoelastic with the irrigation

 

 

 

 

 

Figure 42-10: Eye distended with viscoelastic. Note the rhexis

aspiration probe (Figure 42-12).

 

 

 

 

 

 

 

 

 

 

 

margins.

Contents

Section 1

Section 2

Section 3

Section 4

Section 5

Section 6

Section 7

Subjects Index

Help ?

456 SECTION VII

NO ANESTHESIA CATARACT / CLEAR LENS EXTRACTION

Figure 42-11: Plate haptic foldable IOL with large fenestrations being implanted.

Stromal Hydration

 

At

the end of the procedure, inject the BSS

inside the

lips of the clear corneal incision

(Figure 42-13). This will create a

stromal hydration

at the wound. This will create a

whiteness, which

will disappear after 4-5 hours. The advantage of this

is that the wound gets sealed better.

No Pad, S/C Injections

 

 

 

No

subconjunctival

injections or pad are put

in the eye.

The patient

walks out of the theatre and

goes home. The

patient is seen the next day and after

a month glasses prescribed.

 

 

 

 

 

 

 

 

 

Contents

 

 

 

 

 

 

Section 1

 

 

 

 

 

 

Section 2

 

 

 

 

 

 

Section 3

 

 

 

 

 

 

Section 4

 

 

 

 

 

 

Section 5

 

 

 

 

 

 

 

 

 

 

 

 

Section 6

 

 

 

 

 

 

Section 7

Subjects Index

Help ?

Figure 42-12: Foldable IOL in capsular bag. Viscoelastic re- Figure 42-13: Stromal hydration done and the case completed moved with the irrigation aspiration probe.

LASIK AND BEYOND LASIK

457
Chapter 42

 

NO ANESTHESIA CLEAR LENS

 

that

 

the vacuum

can be raised from 120 to 200 mm

 

 

EXTRACTION

 

 

of Hg. After

embedding the

phaco needle with mild

 

 

 

 

linear ultrasound

power

in

foot switch

position 3,

 

 

 

 

 

 

 

 

In cases of clear lens removal’s, the same

it is important to raise the pedal

back

to foot

switch

 

 

position 2, while the vacuum builds

up.

 

This

is

 

technique is followed. No anesthesia is used. If one

 

 

because

 

the purpose of ultrasound was to completely

 

 

is not good then it is advisable to use a parabulbar

 

 

 

embed the aspiration port into the nucleus to obtain

 

 

 

anesthesia (pinpoint anesthesia) rather than a

 

 

 

good vacuum seal.

In foot switch 3, there is risk of

 

 

peribulbar block. The reason is that in such cases one

 

 

adverse heat build up because the occluded

tip

 

 

could perforate the globe with the needle. Once the

 

 

prohibits any flow of cooling. Also, when

manipu-

 

 

patient is draped, the syringe with viscoelastic is taken

 

 

lating

the nucleus by pulling with the embedded tip,

 

 

and the viscoelastic injected inside the eye using a

 

 

the

vacuum seal is likely to be compromised by the

 

 

26-gauge needle. Then the temporal clear corneal

 

 

vibrating needle if it is in foot switch position 3.

 

 

 

incision is made. If the astigmatism is + at 90 degrees

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

then a superior incision is made.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The rhexis is then done using a needle. This

Advantages

 

 

 

 

 

 

 

 

 

 

 

 

 

is followed by hydrodissection. The phaco probe is

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

passed into the eye and using phaco aspiration the

 

 

 

The

 

phacoemulsification

procedure

 

Contents

 

soft nucleus removed. One does not have to use

 

 

 

 

has

 

been

 

proved

 

to

be reasonably safe to the

 

ultrasound, as the nucleus in such cases is very soft.

 

 

 

endothelium. As compared

to the “divide and

Section 1

 

This is followed by cortical aspiration. Depending

 

 

conquer” technique,

this

phaco karate

chop Section 2

 

on the Biometry a foldable IOL is implanted in the

 

technique eliminates the need for trenching

thereby

 

 

eye. If the patient has high myopia and an IOL is not

Section 3

 

producing significant reduction in phaco time and

 

 

required then an IOL is not implanted. The authors

 

 

 

power

 

consumed which

in

 

turn

decreases

 

have realized that chances of retinal detachment do

endothelial cell

 

damage.

Even

with increased

Section 4

 

 

 

 

not increase just because the eye is aphakic. The

 

 

 

density

of cataract, there is a less pronounced

in-Section 5

 

authors prefer to keep one eye emmetropic and the

crease

in phaco time. Here we utilize the “Chop” to

 

Section 6

 

other slightly myopic to about 1 to 1.5 D so that the

 

 

divide

the nucleus by mechanical energy. It is safe

 

 

patient can see without glasses for distance and near

 

 

 

and

effective

in

nuclear

handling

during

 

Section 7

 

with both eyes open.

 

 

 

 

 

 

 

 

phacoemulsification.

 

 

 

 

 

 

 

 

 

 

 

Compared to Lasik this is a very good

 

 

 

 

 

 

 

 

Subjects Index

 

 

 

 

In

conventional

 

 

 

 

 

 

 

 

alternative, as Lasik does not help much in hyperopes

 

 

 

chop, the disadvantage is

 

 

that the

 

chopper

is placed

underneath the anterior

 

 

and in high myopes (powers above –15 D).

 

 

 

 

 

capsule and then

pulled

towards the

center.This

 

 

 

 

 

 

 

 

 

 

Phacodynamics of the

 

 

can potentially damage the capsule

and

the zonules.

 

 

 

 

In

phaco

chop, we don’t go

under

the rhexis,

the

 

 

Phaco Chop Technique

 

 

vertical element of the chopper remains within the

 

 

 

 

 

 

 

 

 

rhexis

margin and is visible at all stages. Hence very

 

Help ?

 

We

should take full advantage of the phaco

easy

to

work

with

even

in

small

pupils or

 

 

 

machines

capability thereby decreasing

 

glaucomatous eyes. The stress is taken by the

 

 

 

physical

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

manipulation

of

the intraocular tissues.

 

impacted phaco tip and the chopper rather than

 

 

 

In this

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

phaco chop technique, we use a vacuum of 101 mm

transmitting it to the fragile capsule.

 

 

 

 

 

 

 

of Hg, about 70% phaco power and the flow rate is

 

 

 

By

going directly into the centre of the

 

 

24 ml/minute.

 

 

 

 

nucleus with the

phaco tip and not doing any

 

 

 

 

 

 

sculpting, we don’t need as much ultrasound energy

 

 

 

In

this phaco chop technique, the most

 

 

 

important is

the

vacuum, which

needs to be as is usually required. It is safe and easy

to

perform

 

 

sufficient to stabilize the nucleus while

the chopper

and

 

we don’t have to pass as much balanced salt

 

 

 

is splitting

it.

If the action of

the

 

solution

 

(irrigating fluid) through the eye.

 

 

 

 

 

chopper

is

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

dislodging the vacuum seal on the phaco tip, it is said

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

458

SECTION

VII

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
is high, which in turn generates heatThis. causes pain to the patient. If you follow these rules one can perform o anesthesia cataract or clear lens
to extraction surgery. It is not necessary to do this, as there is no harm in instilling some drops of xylocaine
in the eye. The point that there is always a discussion which anaesthetic drop to use. It does not matter. The technique, which you perform, should not produce pain to the patient.

NO ANESTHESIA CATARACT / CLEAR LENS EXTRACTION

Disadvantages

This technique demands continuous use of the left hand and hence requires practise master it.

Topical Anesthesia Cataract /

Clear Lens Surgery

All cases done by the authors were previously

Blurhex (Trypan Blue) in

done under topical anesthesia.

4%

xylocaine drops Mature Cataracts

was instilled in the eye about 3 time’s 10-15 minutes

 

 

before surgery. No intracameral anesthesia was used.

 

Various techniques are present which can

It is not advisable to use xylocaine

drops while

operating. This can damage

the epithelium and help one perform rhexis in mature cataracts.

create more trouble in visualization. No

stitches and

One should use a good operating microscope. If

no pad are applied. This is called the No Injection,

1.

 

the operating microscope is good one can faintly

No Stitch, No Pad Cataract Surgery Technique.

 

 

see the outline of the rhexis.

Now the authors have shifted all their cases 100 % to

 

 

 

the No anesthesia technique. This is done in both their

2.

Use of an endoilluminator. While one is perform-

hospitals in India (Chennai & Bangalore) and their

 

ing the rhexis with the right hand (dominant

hospital in Dubai (UAE).

 

 

 

 

 

 

 

 

hand), in the left hand (non-dominant hand) one

 

 

 

 

 

No Anesthesia Cataract /

 

 

 

can hold an endoilluminator. By adjusting the

 

 

 

endoilluminator in various positions, one can

Clear Lens Surgery

 

 

 

 

 

 

 

 

complete the rhexis as the edge of the rhexis can

We had been wondering whether any topical

 

be seen.

 

 

anesthesia is required or not. So we then operated

3.

Use of a forceps. A forceps is easier to use than a

patients without any anesthesia.

In these

patients no

needle especially in mature cataracts. One can

xylocaine drops were instilled.

The

patients did

not

use a good rhexis forceps to complete the rhexis.

have any pain. It is paradoxical because we have

 

been taught from the beginning that we should apply

4. Use of paraxial light.

xylocaine. This is possible

because we do not touch

But with all these techniques, still one is not

the conjunctiva or sclera.

eWnever

use

any one-

tooth forceps to stabilize the

eye.

Instead what

 

very sure of completing a rhexis in all cases. Many

we

use is a straight rod which is passed inside the eye

to

times if the rhexis is incomplete, one might have to

stabilize

it when we are performing rhexis

etc.

 

convert to an Extracapsular cataract extraction to pre-

The

first step is very important. In this we first enter the

vent a posterior capsular rupture or nucleus drop.

eye with a needle having viscoelastic and inject the

The solution to this problem is to have a dye,

viscoelastic inside the eye. This is done in the area of

which stains the anterior capsule. This dye is

the side port. Now, we have an opening in the eye

TRYPAN BLUE. It is marketed as Blurhex made by

through which a straight rod can be passed to stabilize

Dr.Agarwal’s Pharma. Each ml of Blurhex contains

the eye. The anterior chamber

should be well

0.6 mg Trypan blue, 1.9 mg of sodium mono-hydro-

maintained and the amount

of

ultrasound power gen orthophosphate, 0.3 mg of sodium di-hydrogen

used

very less. If you tend to use

 

 

 

orthophosphate, 8.2 mg of sodium chloride, sodium

the techniques

like trenching then the ultrasound power generated hydroxide for adjusting the pH and water for injection.

Contents

Section 1

Section 2

Section 3

Section 4

Section 5

Section 6

Section 7

Subjects Index

Help ?

LASIK AND BEYOND LASIK

459
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