Cataract Extraction with Phacoemulsification and Posterior Chamber Intraocular Lens

CHAPTER 1

I am Daniel Hu.I am an assistant professor of ophthalmologyat Tufts University School of Medicine andthe New England Eye Center, Tufts Medical Center.And today we will be talking aboutcataract extraction using phacoemulsificationwith implantation of the posterior chamber intraocular lens.After prepping and draping the patient,you know, we- I like to use a Lieberman speculumto, you know, keep the lids open.And then we'll create a paracentesisto access the anterior chamber.And we'll fill the anterior chamber with viscoelastic,and then we'll use a keratome blade tocreate the main incision.Then with a cystotomeand Utrata forceps, we'll createthe capsulotomy. We'll hydrodissectand hydrodelineate the lens nucleus.We'll then fragment the lens nucleuswith a phacoemulsification handpiece.Then remove the cortical remnantswith automated irrigation aspiration.We will then inject theintraocular lens and the capsular bag,and remove any remaining viscoelastic materials.And then check the wounds,seal everything up, and-the case is done.I'll be showingthe divide and conquer technique.I believe it's-one of the easier techniquesto learn for beginning surgeons.One of the benefits of it isthat it can be very gentleto the capsular bag if done properly.And doing socreates very little zonular stressand, I think, lowersthe potential risk for complications.So it's a very safe and gentle procedure.We'll be doing surgery today with\Nan Alcon Infiniti machine,and we'll be using a 2.5-mm incision,and for my second instrument,\NI'll be using a Grayson spatula.I like to use that instrument because it'sgot sort of a wide, flat end to it without any sharp edges.So, for this particular technique, it's particularly usefulbecause I wont be needing to be doing any choppings.Primarily, I'll be using it for lens manipulation, rotation, and splitting,and so it's an excellent instrument for that purpose.

CHAPTER 2

So here, in my right hand I have a0.12 clear B forcepsto stabilize the globe.I have a 1.1-mm side port bladeto create the paracentesis.

And this patient had aperibulbar block, so the next step hereis to inject dispersive viscoelasticto fill the anterior chamber to the appropriate tension.

Here it's important to note thatthe appropriate tension is importantas a too soft eye willpredispose you to a long incision,and an over-inflated eye.It may create a short incision.And here I am stabilizing the eye with the0.12 clear Bs to the paracentesis, and with the2.5-mm keratome blade I am creating thetemporal main incision just anterior to the limbus.Here I'm creating atriplanar corneal incision,which is important in creating a watertight incision.

CHAPTER 3

And here, we are initiatingthe capsulotomy with the cystotome.I like to place the cystotomeon a cohesive viscolastic.This allows me if I encounter any trouble withthe capsule running out or notturning in the direction I like-with the cystotome, I can immediatelyinject the cohesive viscoelastic to try toaid in redirecting the capsulotomy.

Here Utrata forcepsare then used topropagate the initial capsulotomy with\Na continuous curvilinear capsulorhexis.And here as we create thecontinuous curvilinear capsulorhexis,I like to shoot typicallyfor approximately 5-mm capsulotomy,and this givesexcellent overlap of the lens optic,which is appropriately 6 mm.

So following completion of the capsulotomy,we mobilize the lens nucleus with hydrodissection.I like to use a flat cannulafor hydrodissection.It propagates a nice fluid wave.Here, we've also-hydrodeliniated the lensas you can see withthe golden ring sign here.And-following hydrodissection, we ensure good mobilizationof the lens by turningthe lens nucleus in both clockwiseand counterclockwise direction.

Once we've demonstratedgood mobility and rotation of the lens,anterior with the phacoemulsification handpiece-here, we're initiating the initial groovein order to split the nucleus into 2 halves.I'm using a Grayson\Nas my second instrument.And we'replacing both the Grayson andthe phacoemulsification handpiece deepinto the base of the groove.Following the initial crack, I move on togroove the first heminucleus,and again, crack it into quadrants.And this process is repeatedfor the second heminucleus.Aftercreating 4 quadrants,we switch to the quadrant removalsetting on the phacoemulsification machine,and...We bring the initial quadrantforward into the iris plane.There I was unable topurchase the first piece,but we were able to debulk it somewhat,and moving on to the second piece,we were able to elevate it up into the iris plane.We elected to move forward to the second piece asmost of the central nucleusI haven't aspirated,and I don't like toreach too far out into the peripherywith a phacoemulsification handpiece.Any surge orinstability can create capsular rupture.So again, you can notice thatthroughout quadrant removal,the second instrument, the Grayson,has been useful to help mobilize andessentially feedthe phacoemulsification handpiece.And here we have the last quadrant,and it's important to be careful at this stagewith the last quadrant as theposterior capsule can be very floppy.And, with any post-occlusion surge,the posterior capsule can move anteriorly and-be popped by the phacoemulsification handpiece.As we were able to achievegood hydrodelineation in this case,epinuclear shell was then removedon the epinuclear setting onthe phacoemulsification machine.Now the nucleus and the epinucleus have beencleared from the capsular bag.

Irrigation-aspiration handpiece is introducedto remove the cortical remnants.I like to-go after the subincisional cortex firstas the residual cortex-filling the capsular bag tends tohelp hold the posterior capsule back.So, as you can see, I'm-\NI've turned the port down.You'll notice that I havequite long capsular tags.This is intentional as I didn'tdo any central cortical cleanup priorto initial phacoemulsification that helps meto facilitate cortical cleanup,especially with the subincisional cortex.So we slowly make our way around-clearing up the cortex 360 degrees.Now we inspectthe posterior capsule.We do see some lens epithelial cells\Npersisting on the posterior capsule.So I'm doing a little bitof mechanical polishingwith the irrigation-aspiration handpiece.And here I've-despite the mechanical rubbing,some of the lens epithelial cells persist,so I turn the port down.

I do attempt to polish, butthe posterior capsulecame up to the port a bit,so I elected to switch toa Nightingale capsular polisher.This is donewithout any viscoelastic,and this does a very nice jobof removing any central lens epithelial cells.

Following completion of capsular polish,I inject acohesive viscoelastic to fill the capsular bag.And this creates theappropriate amount of spacefor the injection of the lens implant.

Here I'm injecting a 1-piece acrylic intraocular lenswith a wound-assisted technique.And I like to inject the lens directly into the capsular bag.Here I'm using a Kuglen hook toensure that the lens and the haptics arecompletely in the capsular bag.And I use the Kuglen hookto center the lens properly.I like tokeep my lens haptics withthese 1-piece acrylic lenseswith the square edge at the3- and 9-o'clock positionsto try to limitany chance of negative dysphotopsia postoperatively.

Following centration of the IOL,automated irrigation-aspiration is usedto remove the remaining viscoelastic material.Here, I'm clearingthe anterior chamber of boththe cohesive and any leftover dispersiveviscoelastic.I'm tilting and tapping the IOLto removeor capture any of the viscoelastic thatmight be trapped behind the intraocular lens.I also like to sweep the anglesfor any dispersive viscoelastic.

CHAPTER 4

Now, the case is completed.I am forming the anterior chamberand hydrating the temporal corneal incision.A little hydration of the paracentesis as well.Checking the ocular tensions.It's a little soft, soI inject a little bit more balanced salt solution.

And then, checking the incisions with the Weck-Cel.I like to press on the posterior wound edge.Here we see a little bit ofan egress of BSS,so a little bit more stromal hydration.Again, checking the tension.And, again the Weck-Cel's to checkfor any leakage at the temporal wound.And a little bit of pressure.The wound appears dry.One last check of the tension.It was a little bit firm, soburp in the paracentesis to release a littlebit of balanced salt solution.One last check of the wound.Both the temporal incision and the paracentesisappear to be watertight.We remove the lid speculum.The drapes are removed,and then the eye is dressedwith an antibiotic/steroid ointment, and a soft patch, and hard shield.

CHAPTER 5

Hydrodissection in any phacoemulsification technique is very important.Good rotation of the lens nucleus is critical forlens manipulation and reducing zonular stress.It allows for better stability of the capsular lens complexand positioning of the implant,so it really decreases the risk of complications byhaving good hydrodissection.And after that, I think,you know, for this particular technique,a good deep central groove,I find, is more important thanhaving long grooves, so thethickest part of the lens is centrally.So here,a good deep central grooveis really critical to get through any denseposterior plates that might be in the nucleus,and we will allow good propagation of yournuclear cracking.The othertip that I would suggest isbefore the initial groove,instead of doing a little bit of cortical cleanup,to leave the cortical tags there after allthe nucleus is removed.Those long cortical tags really help tofacilitate cortical removal, especiallythe sub-incisional cortex.I'll be using a 1-piece acrylic lens.\NIt's the AMO Tecnis 1.I like to use itbecause of the ease of injection, and theway that it sits in the capsular bagis very nice.It has good optical quality and-a good stability, and the designwith the square edge is thought toreally minimize the risk of posterior capsule opacity.Phacoemulsification machinesare quite efficient.The fluidics are quite good.I'm sure that there will continue to besmall incremental changes in the efficiencyand the fluidics of the machines,but-phacoemulsification hassort of stabilize in its advancements in termsof the ultrasound technology itself.The improvements-I feel will be more related tothe fluidics and the stability of the fluidswithin the eye during the surgery.As far as,you know, what we have availablewhere the future lies in supplementsto the surgery to improve our outcomes,You know, there are severalthings that are available-several technologies that are already availablethat can help to improve our outcomesand the safety of our surgeries.Intraoperative aberrometry hasreally become an important toolin our ability to predict or improveupon the predictability of our refractive outcomes.This allows us to obtain real time dataafter the cataract has been removedto confirm the powerof our lens implants.And there are also- these aberrometerscan also help us to align anyastigmatic correctionthat we're planning to use as well.Additionally, femtosecond lasers have beenincorporated into cataract surgery as well, again,to try to improve uponthe safety profile of already an extremelysafe procedure by improving the reproducibilityof the capsulotomy as well asdecreasing the use of ultrasound bypresoftening the lens nucleus.Patients are typically on topical medicationsfor approximately 1 month.These include an antibiotic drop,a topical nonsteroidal,and a topical steroid.Most patients will have some limited physical activity-no heavy lifting or straining.Generally, I tell my patients not to lift anythingmore than 5 or 10 pounds for at least the first week-first month would be preferable.We try not tohave them get any water in the eye,or, really critical is, that they don't rub their eyes during the procedures.And we have them wear a shield at nighttimefor the first week or two also,just when they're sleeping at night to try tolimit any-unintended trauma while they're sleeping at nighttime.