- Medically Reviewed by: Mr Mfazo Hove, Consultant Ophthalmic Surgeon
- Author: Mr Mfazo Hove
- Published: August 11, 2026
- Last Updated: August 6, 2026
Improvisation under the microscope is not the absence of a plan. It is the presence of every plan.
Where The Disassembly Plan Is Made
On a high-volume list I do not personally examine the cataract at the slit lamp before the patient reaches theatre. The assessment has been done, the biometry performed, the patient listed and consented. It has simply not been done by me. The first time I see the nucleus with my own eyes is after the drape is on, the microscope is down and the eye is open.
In my own clinic the situation differs, but the consequence is much the same. I do examine those patients myself, yet the interval between consultation and theatre is frequently several months, and a nucleus can behave under the microscope quite differently from the way it appeared at the slit lamp. Density grading is useful, but it is not definitive. A lens graded as moderate can prove leathery at the posterior plate, and a nucleus that looked formidable can crack at the first attempt.
In either setting the pre-operative view informs the plan. It does not fix it. The pre-operative assessment establishes the operation: the lens, the refractive target, the anaesthetic, the pupil strategy, the management of any known zonular weakness. What it cannot establish is how the nucleus will be dismantled. That decision belongs under the microscope, and this article is about that decision alone.
If the disassembly plan is made under the microscope, then every disassembly plan must already be available to you when you get there.
The Toolbox
The techniques I keep fluent are the classics, and it is worth naming them properly, because each was a genuine advance rather than a stylistic preference. Howard Gimbel described divide-and-conquer nucleofractis in 1991, and it remains the foundation for many dense nuclei: a deep cruciate groove followed by mechanical cracking into quadrants.¹ Kunihiro Nagahara presented phaco-chop at the American Society of Cataract and Refractive Surgery meeting in 1993, eliminating central sculpting altogether by splitting the nucleus with the chopper against an occluded phaco tip.² Paul Koch and Leslie Katzen published stop-and-chop the following year, and it sits neatly between the two: one central trench, a crack into halves, then horizontal chops of each heminucleus.³ Howard Fine’s chip-and-flip, described in the same year as divide-and-conquer, retains its place for softer lenses, where the nucleus is reduced centrally and the residual bowl is flipped and emulsified within the bag.⁴
AWIC: Any Way It Comes
To these four I add a fifth, which I call AWIC: Any Way It Comes. It is not a formal nucleofractis technique, it has no published description, and it is not taught. It is the freedom to combine elements of all the others according to what the nucleus will actually permit on the day, governed by two constraints only: keep the posterior capsule intact and keep the endothelium quiet. Most experienced surgeons will recognise it immediately. Few write it down, perhaps because naming it sounds like an admission that the plan failed. It is the opposite. AWIC is only available to a surgeon who can already execute the four named techniques on demand, because it consists entirely of their components.
I have practised all of them until each is automatic. That is the precondition. Improvisation is not available to a surgeon with one technique, because a surgeon with one technique must make every cataract fit it. Improvisation only becomes possible once no option carries a cognitive cost.
Matching The Technique to the Eye in Real Time
Because the definitive view is intraoperative, the decision is made at hydrodissection and confirmed with the first occluded bite. Hydrodissection tells you a great deal: how freely the lens rotates, how cleanly the cortical wave passes, whether the nucleus is behaving as a solid body or as something softer and more yielding. The first bite confirms it. From that point the technique is chosen, not recalled.
Most ordinary moderate nuclei accept primary chop. If the first chop does not propagate cleanly, whether because the lens is softer than expected and will not hold the split, or because the posterior plate refuses to separate, I convert immediately to stop-and-chop. The central groove I would have made anyway becomes the starting point for the hybrid, and nothing is lost except a few seconds. This is the part that matters most, and it is the part hardest to teach: there is no ego attached to the original plan. A surgeon committed to demonstrating that primary chop was the right choice will spend far longer proving it than a surgeon who simply changes approach. Changing technique is not failure. Persisting with the wrong one is.
The result, across a list, is a series of operations that look markedly different from one another under the microscope and remarkably similar on the clock. That consistency is the point, and I will return to it.
What The Literature Supports, And What It Cannot Capture
The comparative evidence is consistent in its broad direction. Peter DeBry, Randall Olson and Alan Crandall demonstrated substantially lower phacoemulsification energy with phaco-chop than with divide-and-conquer, with no difference in complications.⁵ Tina Wong, Melanie Hingorani and Vaughan Lee found the same advantage in both time and power.⁶ Juwan Park and colleagues, in a prospective randomised trial of coaxial microincision surgery, showed that the advantage of chop over the other two techniques was clearest in grade 4 nuclei, which is to say that the benefit is density-dependent rather than universal.⁷ Michele Coppola and colleagues found that both divide-and-conquer and stop-and-chop are efficient during the learning curve, with stop-and-chop dissipating less energy in harder nuclei.⁸ A recent systematic review and meta-analysis by Jaime Guedes and colleagues pooled nine studies and concluded that chop delivers less intraocular ultrasound energy and is less hazardous to the corneal endothelium.⁹
Read together, these papers make a point that is rarely drawn out. They do identify measurable overall advantages for chop over divide-and-conquer, in energy, in time and in endothelial cell loss. What they do not identify is one technique that is superior for every nucleus, every eye and every surgeon. The magnitude of the advantage varies with nuclear density, which is precisely the argument for holding the full range rather than adopting the winner. What the existing comparative literature does not capture is the value of switching mid-case once those techniques are second nature. Conventional studies allocate a technique in advance. Real lists do not work that way.
The Nuclei That Refuse to Free-Style
Brunescent and rock-hard nuclei still demand respect, and this is where the argument earns its keep. In my hands, truly brunescent or rock-hard nuclei, particularly those with a leathery posterior plate, often do not lend themselves to a pure primary chop without excessive force or an incomplete split. Other expert surgeons use direct chop successfully in dense lenses, and the energy data would support them in doing so. My own preference in these eyes is divide-and-conquer or a deliberate stop-and-chop. The additional sculpting creates working space, reduces the risk of sudden nuclear displacement and limits zonular stress.
This is the point of the whole approach, and it is the opposite of what the word improvisation usually implies. Mastery does not mean forcing every case into the technique with the best published energy figures. It means recognising when a slower, more deliberate approach is the safer one, and being entirely willing to take it. The measure of flexible technique selection is not how often it produces the fastest option. It is how reliably it produces the right one.
The Young Clear Lens
Occasionally the patient is young and the cataract is really a refractive lens exchange. The nucleus is soft, almost gel-like, and offers nothing to groove and nothing to chop. Here I hydrodissect until the lens can be elevated supracapsularly beneath a maintained dispersive ophthalmic viscosurgical device barrier, then aspirate it in one continuous, near-zero-energy manoeuvre. It is worth being exact about the distinction: this is aspiration of a soft lens, not emulsification of a nucleus. No grooves, no chops, no flipping, and effectively no ultrasound.
The obvious objection is endothelial, and it deserves a direct answer rather than a footnote. Any manoeuvre performed above the capsule places the lens material closer to the endothelium than the same manoeuvre performed within the bag, and I would not defend a supracapsular approach as a general technique. It is confined to genuinely soft lenses in younger eyes, where ultrasound time is negligible or absent, and it depends entirely on maintaining the dispersive barrier throughout, applying the soft-shell principle described by Steve Arshinoff.¹⁰ That paper establishes the protective principle. It does not validate this particular method of lens removal, and I present the manoeuvre as my application of the principle rather than as something the literature has tested. Applied to a nucleus of any real density it would be indefensible. That is the argument, not an exception to it: what determines whether a technique is safe is whether it has been matched to the material in front of you.
Does It Hold Up?
An argument of this kind has to answer one question. Flexible technique selection sounds attractive in prose. Does it withstand scrutiny in outcome data?
I have published National Ophthalmology Database returns for six consecutive years. Across that period my posterior capsule rupture rate has run at approximately 0.2 per cent, against a national benchmark of approximately 0.69 per cent, over a career series now exceeding 57,000 procedures. I offer this with an important qualification. A single surgeon’s series cannot establish that flexible technique selection is superior to a single well-drilled technique, and I would not claim that it does. High case volume, consistent equipment and a stable theatre team all contribute. What the data can establish is the narrower and more useful point: this approach is not achieved at the expense of safety. The most common objection to moving between techniques is that it introduces variability where consistency should be. Six years of published returns suggest otherwise.
Publishing the outcome data is not incidental to the argument. It is the only thing that separates a description of how one surgeon operates from a claim about how surgery should be done.
The 4-Minute Phaco™
I have given this a name, the 4-Minute Phaco™, and screened the surgical film at the Royal College of Ophthalmologists Annual Congress in 2025. It is worth being precise about what the name claims, because it is easily misread. It is not a target. Nobody should operate to a clock, and a surgeon who does will eventually meet the case that punishes it. The four minutes refers to the duration of the phacoemulsification procedure, not to the machine-recorded ultrasound time, which is a small fraction of it. The significant thing about the figure is not simply that it is short. It is that it is consistent.
That consistency is the entire argument restated as a number. A theatre list is not a homogeneous population. It contains soft posterior subcapsular lenses, moderate nuclear sclerosis, the occasional brunescent nucleus that will not yield to a chopper, and now and then a young clear lens that is barely a cataract at all. If one technique were applied across that range, operative duration would vary with the material, because the material varies. Soft lenses would be quick and dense ones slow, and the list would produce a wide spread of durations.
A roughly constant output from a variable input is not evidence that the eyes were similar. It is evidence that the method was not.
The duration holds because the technique changes to absorb the variation the nucleus introduces. Primary chop where the lens will take it. Stop-and-chop where the first chop fails to propagate. Deliberate divide-and-conquer where a brunescent nucleus demands the working space and the additional sculpting is the safer course. No nucleofractis at all where the lens is soft enough to be removed by continuous aspiration. Four eyes, four routes, four broadly comparable operations. The name therefore describes an outcome rather than a method, and the outcome is reproducible precisely because the method is not fixed.
It follows that the efficiency is not won by operating faster. When every technique is fluent, decision latency disappears. You do not pause to recall the sequence of stop-and-chop, because you have performed thousands of them. You do not fight a nucleus that refuses a primary chop, because changing the plan costs nothing. The time is won by never spending any of it on a case you approached the wrong way.
The remarkable feature, then, is not that this occasionally produces a four-minute operation. Any surgeon will have fast cases. It is that the same unhurried rhythm can be reproduced across almost every routine case, despite the nuclei being different every time. Reproducibility is the claim, not speed.
Consistency does not require performing the same manoeuvres in every eye. It requires reaching the same safe endpoint, whatever manoeuvres the eye demands.
This holds whether the patient was seen by me in clinic three months earlier or arrives on a list I have not personally assessed. The interval and the setting do not alter the operating principle. The eye under the microscope dictates the technique, and the surgeon’s task is to arrive with every technique already in hand.
References
- Gimbel HV. Divide and conquer nucleofractis phacoemulsification: development and variations. J Cataract Refract Surg. 1991;17(3):281-291.
- Nagahara K. Phaco-chop technique eliminates central sculpting and allows faster, safer phaco. Ocul Surg News. 1993;10:12-13.
- Koch PS, Katzen LE. Stop and chop phacoemulsification. J Cataract Refract Surg. 1994;20(5):566-570.
- Fine IH. The chip and flip phacoemulsification technique. J Cataract Refract Surg. 1991;17(3):366-371.
- DeBry P, Olson RJ, Crandall AS. Comparison of energy required for phaco-chop and divide and conquer phacoemulsification. J Cataract Refract Surg. 1998;24(5):689-692.
- Wong T, Hingorani M, Lee V. Phacoemulsification time and power requirements in phaco chop and divide and conquer nucleofractis techniques. J Cataract Refract Surg. 2000;26(9):1374-1378.
- Park J, Yum HR, Kim MS, Harrison AR, Kim EC. Comparison of phaco-chop, divide-and-conquer, and stop-and-chop phaco techniques in microincision coaxial cataract surgery. J Cataract Refract Surg. 2013;39(10):1463-1469.
- Coppola M, Marchese A, Rabiolo A, Cicinelli MV, Knutsson KA. Comparison of two popular nuclear disassembly techniques for cataract surgeons in training: divide and conquer versus stop and chop. Int Ophthalmol. 2019;39(9):2097-2102.
- Guedes J, Pereira SF, Amaral DC, Hespanhol LC, Faneli AC, Oliveira RDC, Mora-Paez DJ, Fontes BM. Phaco-chop versus divide-and-conquer in patients who underwent cataract surgery: a systematic review and meta-analysis. Clin Ophthalmol. 2024;18:1535-1546.
- Arshinoff SA. Dispersive-cohesive viscoelastic soft shell technique. J Cataract Refract Surg. 1999;25(2):167-173.
ABOUT THE AUTHOR
Mr Mfazo Hove
Consultant Ophthalmic Surgeon
MBChB MD FRCOphth CertLRS
Mr Mfazo Hove is a Consultant Ophthalmic Surgeon with experience spanning more than 57,000 procedures. He completed 6.5 years of specialist training at Moorfields Eye Hospital and served for five years as a consultant at the Western Eye Hospital, Imperial College Healthcare NHS Trust. He is the founder of Blue Fin Vision®, a consultant-led private ophthalmology practice operating across London, Essex, and Hertfordshire. His clinical expertise encompasses advanced cataract surgery, refractive lens replacement, laser vision correction, and implantable Collamer lenses (ICL).
A ZEISS Key Opinion Leader, Mr Hove is a respected international speaker with five invited engagements across seven cities in 2026:
- ZEISS China tour (Changsha, Shanghai, and Hangzhou, April – ZEISS APAC User Meeting)
- RCOphth Annual Congress – May – Manchester
- ZEISS EMEA User Meeting (Istanbul)
- ZEISS Lausanne User Meeting (Lausanne)
- European Society of Cataract and Refractive Surgeons Annual Congress (ESCRS, London)
Schedule Your Consultation Today
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