Minimally Invasive Cataract Surgery Ashok Garg, I Howard Fine, David F Chang, Hiroshi Tsuneoka
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Evolution of Phakonit (Minimally Invasive Cataract Surgery)CHAPTER 1

Amar Agarwal
Ashok Garg
(India)
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INTRODUCTION
When Phakonit was started in 1998, I did not realize it would become so popular so fast. I wish, I could say it was a brilliant invention of mine, but I cannot. The reason is this invention (as do all inventions and discoveries) came as a message to me from the Almighty and so the invention is HIS and only HIS.
 
HOW IT ALL STARTED
I am basically a vitreo-retinal surgeon and used to do all my lensectomies with the Phaco handpiece. I did not have a fragmatome (an instrument to remove cataracts by vitreo-retinal surgeons). So I used to remove the infusion sleeve and pass the Phaco needle into the lens through the pars plana. Infusion would be through the infusion cannula which is connected in all vitrectomies. This way I realized I could remove the cataracts in patients in whom I had to continue with vitrectomy for proliferative vitreo-retinopathy or any other posterior segment pathology.
I subsequently began to think about using this system for cataracts for the anterior segment surgeon. The problem was how to have an irrigation system present inside the eye. On August 15th 1998, India's Independence day, the thought of taking a needle, bending it like a chopper and using that for irrigation and chopping occurred to me (Fig. 1.1). I also realized that there could be a corneal burn so thought of irrigating the corneal wound from outside. With this idea in mind, I went to the operation theatre.
We have in our institute doctors from all over the world training in phaco. When I reached the theatre I understood I could not operate on a decent soft cataract as those trainee doctors would have to operate on those patients. So I selected for myself a mature cataract.
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Fig. 1.1: Phakonit done with a bent needle. The needle was bent like a chopper and the first case of Phakonit was done with this instrument. Later on instruments like the refined irrigating choppers were made
In hindsight, I realize it was a good thing this happened as it made me understand that this technique could be done in any type of cataract.
When the case started I took out the infusion sleeve from the phaco handpiece and took a 20 gauge needle and connected it to the irrigation bottle. Then I took a needle holder and bent the needle in such a way that it could also be used for chopping. You can understand when you bend a needle like that it will obviously not come out very well. Another problem with using a needle was that as the needles have a bevel if one pulls out the needle a little bit the bevel would be outside the eye and the chamber would collapse. For the incision I used the micro vitreo-retinal blade (MVR blade) which vitreo-retinal surgeons use for vitrectomies. This does not create a perfect valve as the 4diamond and saffire knives of today do but that was enough at that time.
When I had finished the rhexis, I knew the hydrodissection was important and tricky. The reason was that the incision size was very less and so the amount of fluid escaping from the eye would not be much. So, I was careful that I don't hydrodissect with a lot of fluid, otherwise one can get a dropped nucleus during hydrodissection.
When the surgery started, I realized I was having a lot of anterior chamber shallowing. Whenever I would start to remove the nucleus the chamber would partially collapse. It was obvious that the amount of fluid entering the eye was not enough compared to the amount exiting the eye. So I stopped the surgery and shifted to an 18 gauge needle. To my surprise everything went well after that. I knew then that the amount of fluid now was balanced with an 18 gauge needle. I could chop the hard cataract though not very well as compared to a chopper but I knew with more refined instruments this surgical technique would work. Once the surgery was complete, I realized that this could be the next frontier in cataract surgery as the incision was reduced drastically.
 
TERMINOLOGY OF PHAKONIT
I wanted to give a name to this surgical technique and started thinking of various names. Some names which came to me at that time were microphaco, miniphaco etc. Then I thought of Phakonit which was Phako with a Needle Incision Technology. The reason I thought of this was because we did phaco using a needle (N) through an incision (I) and with the tip (T) of the phaco needle for the surgery. I used in the phaco a K and not a C as I felt it 5looked better with a K and so termed it as PHAKONIT and not Phaconit.
 
NO ANESTHESIA CATARACT SURGERY
At this stage I would like to digress a bit and mention about another discovery of mine. I was operating a patient with a posterior polar cataract. Normally, in such cases I used to prefer to do an extracapsular cataract extraction (ECCE). So when my fellow rang me up and informed me that the case was a posterior polar cataract, I told her not to block the patient as I would do ECCE on the patient. In those days I used to do the ECCE under pinpoint anesthesia or subtenons anesthesia in which I would make a small nick in the conjunctiva and pass a cannula with xylocaine under the conjunctiva and give anesthesia to the patient. This way the patient does not have an injection given and is quite comfortable. When I reached the theatre, I saw the patient and just decided to do Phaco. When I was in the middle of the case my fellow came running into the theatre and was very anxious as she had gone out and I had started the case. She informed me that she had not put any topical anesthetic drops in the eye as I was going to do subtenons anesthesia for ECCE. She was worried that I would be angry with her. But the fact was that I was actually shocked as I was in the middle of the surgery and the patient was not worried at all. So I told her let us see what happens as this patient obviously did not mind the no anesthesia cataract surgery. When I finished the case the patient got up shook my hand and thanked me and left the theatre. This set my mind working as I knew this was abnormal.
On June 13th 1998, I was in Ahmedabad, India for a live surgery for a workshop organized by the Indian 6Intraocular Implant and Refractive society. Though I had discovered that cataract surgery can easily be done without any anesthesia and termed that as no anesthesia cataract surgery, I was apprehensive to do it as I felt it was really absurd. In this no topical anesthetic drops or intracameral anesthesia is used. However absurd it may sound, it was true. So on June 13th 1998, I decided to do the live surgery without any anesthetic drops. The surgery went very well and there were about 250 eye doctors from all over India watching the surgery. In hindsight I do not know what made me do the live surgery without anesthesia as at that time I did not realize how successful it would be. When I came back to Chennai (Madras) where I work, I started thinking about it more. At that time I had a eye doctor from USA training with me. He was Dr Vipul Lakhani. He told me to look as it scientifically and said he would do a double blind study with me. So we took 30 patients in whom my wife (Dr Athiya Agarwal) and I operated upon. 10 were with no anesthesia, 10 with topical and 10 with topical plus intracameral anesthesia. We did not know which patient we were operating upon. Dr Vipul Lakhani would ask each patient the pain factor, etc. At the end he informed me that his p values showed there was no difference between the three groups. Then I knew No anesthesia was a reality and since then have never used topical or intracameral anesthetics. If there is a tough case or uncooperative patient I would operate with a peribulbar block. Later on a similar study was done by us with David Apple and Suresh Pandey which was subsequently published in the journal of cataract and refractive surgery.1,2
 
FIRST LIVE SURGERY OF PHAKONIT
On August 22nd 1998, I had to do a live surgery in Pune, India for the Indian Intraocular Implant and Refractive 7Society Conference. The organizers asked me what live surgery was I going to perform. I informed them that I was going to perform a new surgical technique which I had called Phakonit and would remove cataracts through a 0.9 mm incision. They were very happy and trusted me so much and gave me the confidence to go ahead. The previous night of the live surgery I could not sleep at all. I knew I had to do this new surgery and I had done only 5 cases till then. I also knew I had to operate with just a needle and no refined instruments and under no anesthesia and so was under lot of tension. Anyway, the surgery went off very well and there were about 350 ophthalmologists who watched the live surgery.
 
PHACO BOOK
At that time I was writing my first book which was titled, Phacoemulsification, Laser Cataract surgery and foldable IOL's. The book was to be released in September 1998. I immediately contacted the publishers and informed them that I was sending a chapter titled Phakonit for the book and to please include it though it was quite late as the book was already in press. They agreed and that is how the Phakonit chapter came into publication in 1998 itself.313
 
PREVIOUS WORK DONE
Steve Shearing in 198514 published a paper on separating the infusion from the phaco handpiece. T Hara from Japan in 198715 also did the same. I had not heard of any of this work when the concept of Phakonit was started by me. As gradually Phakonit became more popular work done by these early pioneers got appreciated more and more.8
 
IRRIGATING CHOPPERS
I subsequently worked with many companies to make the irrigating chopper and other instruments for Phakonit like the phakonit knive, etc. Various companies now have bimanual phaco instruments designed by various surgeons of the world.
 
AIR PUMP
One of the main problems in Phakonit was the fluidics. As explained earlier, the amount of fluid entering the eye was less compared to the amount of fluid exiting the eye. My sister Dr Sunita Agarwal (Fig. 1.2) understood this problem and started pushing air into the infusion bottle to get more pressurized fluid out of the bottle.9
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Fig. 1.2: Sunita Agarwal, India. She invented the air pump which is an aquarium pump. This major invention changed Phakonit as with this more air was pumped into the infusion bottle and thus more fluid came out of the irrigating chopper preventing any surge to occur
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When it worked she then took an aquarium air pump and connected it to the infusion bottle via an IV set. This gave a constant supply of air into the infusion bottle and the amount of fluid coming out of the irrigating chopper was quite enough for us to move from an 18 gauge irrigating chopper to a 20 or 21 gauge irrigating chopper. This was the first time pressurized fluid was used in anterior segment surgeries. This invention of air pump was made in 1999 and since then we have never looked back. We use the air pump not only in Phakonit but also in all our Phaco cases.
 
THREE PORT PHAKONIT
Before the air pump I tried to solve the surge problem by fixing an anterior chamber maintainer. This was a three port phakonit.2 But once the air pump invention was made by my sister Sunita Agarwal, we realized we did not need the anterior chamber maintainer. The usage of the anterior chamber maintainer made Phakonit more cumbersome as three ports were made rather than two.
 
LIVE SURGERY FROM INDIA TELECAST TO ASCRS 99
We applied for an instruction course in the ASCRS 99 conference in Seattle. In this we applied for a surgery to be telecast live via satellite from India into the USA to demonstrate Phakonit and No anesthesia cataract surgery. Till date we are very grateful to Dr Manus Kraff, David Karcher and the whole ASCRS team for giving us this course. The live surgery went very well and as we were in India we took the next flight out and gave lectures in the ASCRS taking advantage of the time difference between the two countries. Many courses subsequently were conducted by us on Phakonit and No anesthesia 10cataract surgery in the ASCRS, AAO and ESCRS conferences.
 
WORK DONE IN 1999
In 1999 P Crozafon reported the successful use of a sleeveless 21 gauge Teflon-coated tip for minimally invasive bimanual phaco. Crozafon felt that thermal burn could be prevented by coating the phaco tip with Teflon, which has poor thermal conductivity.
In 1999, Hiroshi Tseunoka from Japan16, 17 studied the use of ultrasonic phacoemulsification and aspiration for lens extraction through a micro-incision (Fig. 1.3). Tseunoka used a larger incision as he felt that when the incision size is larger than the phaco tip, the tip gets cooled by the leakage of infusion solution through the incision. The extra space according to him also prevents deformation at the incision site due to tip movement.
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Fig. 1.3: Hiroshi Tseunoka, Japan
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Fig. 1.4: Jorge Alio, Spain. He coined the term MICS (Microincision cataract surgery)
 
MICROINCISION CATARACT SURGERY
Jorge Alio from Spain18 coined the term MICS or Microincision cataract surgery (Fig. 1.4). This meant cataract surgery being done through a 1.5 mm incision or less. This included laser cataract surgery (pioneering work done by Jack Dodick from USA) and ultrasound (Phakonit).
 
MICROPHACO
Randall Olson (Fig. 1.5) was the first to resurrect interest in the United States starting in the fall of 1999 and then to do studies published in peer review journals to answer the concerns of early critics.1922 He helped in developing new equipment that did not restrict inflow. In 2001 Randall Olson from USA reported the feasibility of sleeveless phaco through a 1.0 mm incision using the Sovereign (AMO, USA) with Whitestar technology.
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Fig. 1.5: Randall Olson, USA. He coined the term Microphaco
Olson found that tip heating could be minimized by setting the machine for pulse mode so that ultrasound was generated for extremely short intervals. He coined the term Microphaco.
 
HUB OF INFUSION SLEEVE
One problem in Phakonit was that there would be a spray of fluid over the cornea whenever one would do Phakonit. To solve this problem, one can use the hub of the infusion sleeve. There would be no infusion sleeve over the rest of the phaco needle but only be present over the base of the needle.3
 
SUB 1 MM CATARACT SURGERY
Using videos and a special vernier caliper sub 1 mm Phakonit surgery was documented and demonstrated. In 13this a 21 gauge irrigating chopper and a 0.8 mm phaco needle was used.3
 
ACRITEC IOL
Christine Kreiner (Fig. 1.6) from Germany made an ultrasmall incision IOL12 using a special co-polymer as the lens material. The first lens was implanted by Kanellopoulos from Greece in 2000.23 This was an Acrismart IOL. She also created a company Acritec to manufacture these IOL's. The first lens implanted was a single piece acrylic IOL which was dehydrated and pre-rolled.
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Fig. 1.6: Christine Kreiner, Germany. She formed the Acritec company and brought out the first ultrasmall incision IOL. This was implanted in the year 2000
 
THINOPTX ROLLABLE IOL
The Thinoptx company headed by Wayne Callahan (Fig. 1.7) made an ultrathin lens using the Fresnel principles.8,10
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Fig. 1.7: Wayne Callahan, USA. He started the Thinoptx company. He brought out a new revolution in IOLs by using the Fresnel principle which made the lens thin and rollable to pass through ultrasmall incisions.
Wayne and Scott Callahan begin developing such a product using an inexpensive lathe, milling machine, and blocking fixture. They then developed a manufacturing process for an extremely thin lens. Most of the work took place in a garage. The first such lens was implanted by Jairo Hoyos from Spain. The second was implanted by Jorge Alio from Spain. They had heard of my work through Kenneth Hoffer (The first President of the ASCRS) and sent me some lenses and I then implanted the lens after Phakonit. I realized also that it would be better to have a smaller optic lens and designed for Thinoptx a special 5 mm optic rollable IOL. They then made this special lens for me and we implanted 5 such lenses. These were the 15first 5 mm optic Thinoptx rollable IOL implanted. The first smaller sized rollable IOL was implanted on Oct 2nd 2001. These lenses could be rolled and hence the name Rollable IOL rather than Foldable IOL. The Company received a CE Mark in September of 2002 and in the spring of 2004 received approval to start a clinical study in the United States.
 
BIMANUAL PHACO
Internationally, the name for Phakonit is Bimanual Phaco. The idea was to separate it from coaxial phaco in which the irrigation is with the phaco handpiece.
 
SUMMARY
Today Phakonit or Bimanual Phaco has taken the ophthalmologic world by storm. This is also know by other names such as MICS or Microphaco. The only problem right now is to get more lenses into the market which will pass through sub 1 mm incisions and at the same time not reduce the quality of vision for the patients. These should also have an excellent injector system and should be user friendly. As one will notice many surgeons and Pioneers from different parts of the world have made Bimanual Phaco reach its present status. We have come a long way in cataract surgery but still have a long way to go. I am sure with the blessings of the Almighty this will also happen.16
REFERENCES
  1. Agarwal A, Agarwal S, Agarwal AT: No anesthesia cataract surgery. In Agarwal, et al. Textbook: Phacoemulsification, Laser Cataract Surgery and Foldable IOLs (1st edn). Jaypee:  India,  1998;144–54.
  1. Pandey S, Wener L, Agarwal A, Agarwal S, Agarwal AT, Apple D: No anesthesia cataract surgery. J Cataract and Refractive Surgery 2001;28: 1710.
  1. Agarwal A, Agarwal S, Agarwal AT: Phakonit: A new technique of removing cataracts through a 0.9 mm incision. In Agarwal, et al. Textbook: Phacoemulsification, Laser Cataract Surgery and Foldable IOLs (1st edn). Jaypee:  India,  1998;139–43.
  1. Agarwal A, Agarwal S, Agarwal AT: Phakonit and laser phakonit: Lens surgery through a 0.9 mm incision. In Agarwal, et al. Textbook: Phacoemulsification, Laser Cataract Surgery and Foldable IOLs (2nd edn). Jaypee:  India,  2000;204–16.
  1. Agarwal A, Agarwal S, Agarwal AT: Phakonit. In Agarwal, et al. Textbook: Phacoemulsification, Laser Cataract Surgery and Foldable IOLs (3rd edn). Jaypee,  India,  2003;317–29.

  1. 17 Agarwal A, Agarwal S, Agarwal AT. Phakonit and laser phakonit. In Boyd/Agarwal, et al. Textbook: Lasik and Beyond Lasik, Higlights of Ophthalmology, Panama, 2000; 463–68.
  1. Agarwal A, Agarwal S, Agarwal AT. Phakonit and laser phakonit. Cataract surgery through a 0.9 mm incision; In Boyd/Agarwal, et al. Textbook: Phako, Phakonit and Laser Phako, Higlights of Ophthalmology. Panama, 2000;327–34.
  1. Agarwal A, Agarwal S, Agarwal AT. The Phakonit Thinoptx IOL. In Agarwals. Textbook: Presbyopia, Slack, USA, 2002;187–94.
  1. Agarwal A, Agarwal S, Agarwal AT. Antichamber collapser. J Cataract and Refractive Surgery; 2002;28: 1085.
  1. Pandey S, Wener L, Agarwal A, Agarwal S, Agarwal AT, Hoyos J. Phakonit: Cataract removal through a sub 1.0 mm incision with implantation of the Thinoptx rollable IOL. J Cataract and Refractive Surgery; 2002;28: 1710.
  1. Agarwal A, Agarwal S, Agarwal AT. Phakonit: phacoemulsification through a 0.9 mm incision. J Cataract and Refractive Surgery 2001;27:1548–52.
  1. Agarwal A, Agarwal S, Agarwal AT. Phakonit with an acritec IOL. J Cataract and Refractive Surgery 2003;29:854–55.
  1. Agarwal S, Agarwal A, Agarwal AT. Phakonit with Acritec IOL. Highlights of Ophthalmology 2000.
  1. Shearing S, Relyea R, Loaiza A, Shearing R Routine phacoemulsification through a 1.0 mm non-sutured incision; Cataract 1985, Jan; 6–8.
  1. Hara T, Hara T. Clinical results of phacoemulsification and complete in the bag fixation. J Cataract and Refractive Surgery 1987;13:279–86.
  1. Tseunoka H, Shiba T, Takahashi Y. Feasibility of ultrasound cataract surgery with a 1.4 mm incision. J Cataract and Refractive Surgery 2001;27:934–40.
  1. Tseunoka H, Shiba T, Takahashi Y. Feasibility of ultrasound cataract surgery with a 1.4 mm incision: Clinical results. J Cataract and Refractive Surgery 2002;28:81–86.
  1. Jorge Alio. What does MICS require in Alios textbook MICS; Highlights of Ophthalmology 2004; 1–4.
  1. Soscia W, Howard JG, Olson RJ. Microphacoemulsification with Whitestar. A wound-temperature study. J Cataract and Refractive Surgery 2002, 28;1044–46.

  1. 18 Soscia W, Howard JG, Olson RJ. Bimanual phacoemulsification through two stab incisions. A wound-temperature study. J Cataract and Refractive Surgery 2002;28:1039–43.
  1. Randall Olson: Microphaco chop. In David Chang: Textbook on Phaco Chop; Slack,  USA 2004;227–37.
  1. David Chang. Bimanual phaco chop. In David Chang: Textbook on Phaco Chop; Slack,  USA 2004;239–50.
  1. Kanellopoulos AJ. New laser system points way to ultrasmall incision cataract surgery; Eurotimes 5/2000.