SURGICAL PEARLS
From the 23rd Annual Current Concepts in Ophthalmology, presented July 16, 2005, by the San Diego Eye Bank
| PHACOEMULSIFICATION AND LENS IMPLANTATION AFTER PARS PLANA VITRECTOMY —Kevin M. Miller,
MD, Professor of Clinical Ophthalmology, Jules Stein Eye Institute, The David Geffen School of Medicine at the University
of California, Los Angeles
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| Typical patient: 76-yr-old man; 5 yr after pars plana vitrectomy for drainage of submacular hemorrhage in right eye;
some dry macular degeneration in left eye; did not have good visual acuity (VA) before cataract developed, but complaining
about inability to drive comfortably (missing peripheral vision)
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| Retrospective study by speaker and Samuel Masket: patients operated on from 1990-1996; all had phacoemulsification
after pars plana vitrectomy; 44 eyes; mean age slightly younger than seen in typical cataract practice; average
interval from vitrectomy to phacoemulsion 20 mo, average from phacoemulsification to final examination 19 months;
primary indications for vitrectomy included epiretinal membrane, macular hole, proliferative diabetic retinopathy (PDR),
and vitreous hemorrhage
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 | Best corrected visual acuity (BCVA): preoperative—average 20/125; no eyes >20/30, 11 eyes <20/400; 6 wk
postsurgery—median improvement from 20/125 to 20/40; 12 eyes ≥20/20, 16 eyes 20/25 to 20/40; only 1 eye <20/
400; final—median 20/30; ≥20/40 in 75% of cases; poor vision after surgery always related to preexisting macular pathology
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| Common macular pathologies identified after surgery: edema; ischemia; scars; choroidal neovascular membranes; epiretinal
membranes; sequelae from retinal detachments
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| Complications: unplanned intraoperative—“trampoline effect,” ie, problematic fluctuation in chamber depth of iris
lens diaphragm due to lack of vitreous support (seen in only 2 cases); posterior capsule plaque (seen in 10 of 44
eyes; in some cases, plaque so severe, primary posterior capsulorrhexis required for removal); posterior capsule
rupture (seen in 1 eye); vitreous loss (4 cases; 3 in eyes that had primary posterior capsulorrhexis); early postoperative
(≤1 wk after surgery)—moderate-to-severe corneal edema; blepharoptosis; moderate-to-severe postoperative
iritis; vitreous through pupil; late postoperative complications (>1 wk after surgery)—left blepharoptosis (1
case); posterior capsule opacification (most frequent complication of cataract surgery; affects 33% of eyes; new
or persistent macular edema (also major complication); epiretinal membranes (very common)
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| Conclusions: phacoemulsification and lens implantation can be performed safely and successfully after pars plana
vitrectomy; median BCVA improves substantially; preoperative status of macula determines ultimate improvement
in VA; intraoperative and postoperative complications not significantly different from those in routine cataract
patients
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| Final comments: can operate on these eyes without too much trouble (speaker worries about eyes with multiple previous
vitrectomies; occasionally see trampoline effect and iris coming down; cataracts tend to be much denser (require more
time; consider using dispersive viscoelastic against corneal epithelium); go slow; counsel patients preoperatively
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| MACULAR HOLE SURGERY —Paul E. Tornambe, MD, Director, San Diego Retina Research Foundation, San Diego
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| Introductory remarks: macular hole management has progressed from inability to repair condition (in 1990) to >98%
success rate in closing hole; mysteries of macular hole (always perfectly round; scotoma 2 to 3 times larger than hole;
only wound that completely vanishes in 2 to 3 days; operculum); endoscopic view of macular hole after staining with indocyanine
green (ICG) shows vitreous still attached at edge and some epiretinal membrane formation (reason for peeling
internal limiting membrane [ILM])
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| Pathogenesis of macular holes: cause unknown; speaker’s theory (retinal hydration)—certain individuals have genetic
susceptibility for vitreofoveal fine attachment; inner retinal defect permits liquid vitreous to enter middle and
outer retina (inner nuclear and outer plexiform layers [INL/OPL]); hydration results in middle and deep intraretinal
swelling with retraction of nonswollen intraretinal structures (ie, “drawbridge effect,” which in turn creates perfectly
round macular hole); supporting evidence (histopathology of macular holes tends to confirm swelling of INL/OPL; extrafoveal
macular holes show no swelling); importance of macular hole genesis theory
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| Macular hole surgery with face-down positioning: rationale for use of face-down positioning strictly historical
(ie, how it was initially decided to do procedure); no studies looking at how long patients need to be kept face down,
how long gas bubble must be against hole, or whether positioning necessary; suggested mechanism of healing (based
on retinal hydration theory)—gas bubble placed in eye to isolate liquid vitreous; retinal pigment epithelium (RPE)
pumps fluid out of INL/OPL; “drawbridge closes,” and fibrin plug forms to fill macular hole; no data to support efficacy
of face-down positioning; not needed, as long as gas bubble kept against hole); no question macular holes can be
closed without routine positioning
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| Speaker’s only indication for face-down positioning: young phakic patients in whom lensectomy not indicated
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| Silicone oil tamponade: 1999 paper suggested macular hole repair could be done with silicone oil; author retracted
statement; speaker generally does not advocate or use oil (except possibly in cases when patient must travel in airplane
next day [and thus experience change in air pressure])
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| Function of gas bubble in macular hole surgery: keeps fluid away from hole, which allows body to promote healing
(example of patient with detached right macula); any way patient positioned so hole closed off from vitreous satisfactory;
face-down positioning simply keeps bubble away from lens (buoyancy not factor; in patient with totally gas-filled eye,
buoyancy almost same whether patient upright or lying down)
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| Comments: face-down approach results in patients (eg, with arthritis) being denied macular hole surgery because they
cannot position themselves; only position contraindicated is on back (can displace intraocular lens [IOL] if there has been
recent surgery, and bubble meniscus may not close hole); in cases of pseudophakic eyes with macular holes, never need
for face-down position
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| In patient >60 yr of age: speaker explains that he or she will inevitably develop cataract in 2 yr, and thus has option; can
opt to have cataract surgery first, then will not have to endure face-down positioning; otherwise, patient has to lie face
down for 5 to 6 days until bubble shrinks a bit, so it does not hit lens; most patients opt to go to cataract surgeon first
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| Surgical technique: same as for any other macular hole; in cases where ILM appears to have epiretinal membrane on surface,
ILM peeling recommended; in stage II holes, usually do not need to peel ILM (as there is no membrane)
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| Technical comments: initially, speaker doing combined cataract and macular hole surgery; no longer does so, but physicians
who do cataract and retinal surgery should do them combined; reinforce corneal wound; “use as big an optic as you
can”; in patient who has had recent cataract operation, administers 1% pilocarpine and does not look at retina until gas
bubble is at 30% (7 days out); problem cases are “very wide-eyed patients” (administers cyclopentolate [Cyclogyl] and
phenylephrine [2.5% Mydfrin] to reduce size of pupil); problems that can occur with combination surgery (significant
rent in capsule during phacoemulsification, just before fluid-gas exchange); nowadays, speaker sends just about all patients
to cataract surgeon for removal of lens, then after 2 wk, does macular hole surgery
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| Speaker’s study (1996): surgery done using intraocular perfluoropropane (C3F8) gas bubble; no face-down positioning;
33 eyes (some combined cataracts, some pseudophakic); mostly stage III and IV holes; 71% one-operation success rate;
speaker repeated study retrospectively in 1997 to 2001 (still using C3F8; success rate 91%)
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| Complications and solutions: capsule rupture—avoid silicone IOLs; iris prolapse—manage with suture; one of
biggest complications with non–face-down positioning is not getting total gas fill; with patient upright, first day postoperatively,
speaker likes to see 85% to 90% gas fill; narrow-angle glaucoma—primarily due to gas overfill; do not use expanding
concentration of gas (speaker always uses 20%-25%, never any higher); after vitrectomy, some anterior rotation
of ciliary spur can narrow angle and produce tendency for this condition; (if condition occurs, may have to remove some
gas); retinal pigment epitheliopathy—can get this without using ICG; just need to hold light probe close enough to
fovea for too long; will get photochemical burn on retina; recommends keeping light as low as possible (nonfocused light
such as bullet or torpedo); try to keep macular hole operating time <10 min; never use >1 mg/mL of ICG
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| If hole does not close: probably have not peeled ILM or have not achieved full gas fill; might be more ideal to use perfluoroethane
(C2F6) bubble; never use triamcinolone (Kenalog)
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| Concluding comments: disadvantage of macular hole repair and cataract surgery as separate operations (clear lens extraction,
but if >60 yr of age, will get cataract anyway); macular hole repair “kinder and gentler” operation (does not require
patient compliance; can be offered to anyone); holes can be flattened and closed without face-down positioning at
rates comparable to those seen in patients positioned face down
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| CHOOSE YOUR WEAPON: WHEN TO CHOP, SCULPT, OR FLIP —Stephen S. Bylsma, MD, Assistant Clinical Instructor,
Department of Ophthalmology, The David Geffen School of Medicine at the University of California, Los Angeles,
and Shepard Eye Center, Santa Maria, California
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| Reasons for varying technique: each technique has unique benefits and unique risks; sculpting—advantages (ultrasonography
[US] farthest from endothelium; technique easiest to learn); disadvantages (requires more US energy;
slower); chopping—advantages (requires far less US energy; faster; more efficient); disadvantages (easier to break capsule;
longer learning curve); flipping—advantages (fastest technique; phacoemulsification tip far from posterior capsule);
disadvantages (tip closer to endothelium, so corneal edema can occur); reason for changing technique is safety
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| Importance of “go to” technique: every surgeon needs to have “go to” technique that he or she can revert to in difficult
situations (eg, higher-risk cases; intraoperative complications); whether sculpting, chopping, or flipping, each surgeon
needs to know best and safest standard procedure in his or her hands
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| Critical factors that make techniques successful: sculpting—depth of groove (harder the nucleus, less groove
depth required to manually crack it); chopping—maintain occlusion and apply proper vector forces; flipping—
dislocate nucleus out of bag toward anterior chamber; avoid endothelium
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| Comments on chopping: more efficient; bit of learning curve (especially for “prechop”); walls need to be vertical to occlude
phacoemulsion tip; need to be able to revert to sculpting at any time; can expect to revert to sculpting often when
learning chopping technique
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| Comments on flipping: fastest; must learn to dislocate nucleus; watch for corneal edema; second instrument critical;
more intermediate or advanced technique; endothelium at risk
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| Which technique to use: determined by surgeon’s experience, nuclear density, and how high risk
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| Surgical experience: beginning—use sculpting only (sculpting preferred “bail out” technique for speaker);
intermediate—begin chopping (good way to transition is to chop after first fragment out); advanced—alternate freely
between sculpting, chopping, and flipping
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| Nuclear density: soft—difficult to chop or crack lens; medium—all techniques work; hard—large amount of US energy
delivered with sculpting; thus, should consider flipping with very hard lenses (brunescent especially)
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| Higher-risk cases: small pupil (do not chop); small capsulorrhexis (do not chop); torn capsulorrhexis (do not flip); guttata
(chopping best); very brunescent lens (flipping best); pseudoexfoliation (anything but flipping); loose zonules or
shallow anterior chamber (best to avoid flipping)
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| Technical points on sculpting: does not matter how deep first groove is (after first sculpt, have to take proximal portion
off before reaching over and getting distal wall); does not matter how deep second sculpt either; with third groove,
have enough room to really go deep; plus, each groove has to be as wide as sleeve); key getting tip deep enough into
groove to get sufficient crack; if lens does not crack, groove not deep enough; speaker’s favorite technique (most bag
friendly; safest for endothelium; main risk is for going through quadrant to posterior capsule, but chances slim; speaker
likes to use large-bore needle
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| Technical points on chopping: technique is embed, gain occlusion, and chop; first chop usually goes all way across,
then embed again, and while nucleus on tip, chop, then simply consume that into port; most efficient; effective and safe;
what speaker starts with in 95% of cases (excluding clear lens extraction)
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| Technical points on flipping: several ways to achieve this; eg, aggressive hydrodissection will flip nucleus; little easier
to do if nucleus oriented vertically so that it is coming forward (less likely to go back into bag); main risk for endothelium;
extremely fast (nucleus consumed very quickly); can use chopper (once speaker has occlusion, he often uses vertical
chop or horizontal chop, “anything it takes”)
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| Concluding comments: examples of cases where speaker reverted to sculpting; “it’s all about getting the first fragment
out; once the first fragment is out, you’re home free” (as long as careful about posterior capsule); all surgeons need “go
to” or “bail out” technique (may vary, but important to have one and not get stuck doing one type of phacoemulsion technique
when many approaches to remove nucleus; read nucleus moment by moment and vary technique accordingly
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Educational Objectives
| The goal of this activity to review some aspects of ophthalmic surgery, with focus on phacoemulsification and macular hole
surgery. After hearing and assimilating this program, the clinician will be better able to:
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| 1. Consider the possibility of phacoemulsification and lens implantation in patients who have had pars plana vitrectomy,
with a better understanding of its efficacy and possible complications.
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| 2. Describe and discuss the retinal hydration theory for the genesis of macular holes.
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| 3. Cite the original rationale for face-down positioning and explain why it is not necessary for macular hole surgery.
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| 4. Alternate between phacoemulsion techniques (sculpting, chopping, and flipping) and tailor the approach to each
case.
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| 5. Choose and maintain a “go to” phacoemulsification technique that can be reverted to in difficult situations.
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Discussed on This Program
Acetylcholine chloride, intraocular [Miochol-E]
Cyclopentolate HCl [AK-Pentolate, Cyclogyl, Pentolair]
Homatropine HBr [Isopto Homatropine]
Phenylephrine HCl [Mydfrin 2.5%, other trade names and preparations]
Pilocarpine Ocular Therapeutic System [Ocusert Pilo-20, Ocusert Pilo-40]
Polydimethysiloxane (silicone oil) [AdatoSil 5000]
Triamcinolone acetonide [Kenalog, other trade names and preparations]
Suggested Reading
Ahfat FG, Yuen CH, Groenewald CP: Phacoemulsification and intraocular lens implantation following pars plana
vitrectomy: a prospective study. Eye 17:16, 2003; Biro Z, Kovacs B: Results of cataract surgery in previously vitrectomized
eyes. J Cataract Refract Surg 28:1003, 2002; Grusha YO, Masket S, Miller KM: Phacoemulsification and
lens implantation after pars plana vitrectomy. Ophthalmology 105:287, 1998; McDermott ML et al: Phacoemulsification
for cataract following pars plana vitrectomy. Ophthalmic Surg Lasers 28:558, 1997; Pinter SM, Sugar A: Phacoemulsification
in eyes with past pars plana vitrectomy: case-control study. J Cataract Refract Surg 25:556, 1999; Raj
A: Phacoemulsification and intraocular lens implantation following pars plana vitrectomy: a prospective study. Eye
19:218, 2005; Simcock PR: Phacoemulsification and intraocular lens implantation following pars plana vitrectomy: a
prospective study. Eye 19:480, 2005; Simcock PR, Scalia S: Phacovitrectomy without prone posture for full thickness
macular holes. Br J Ophthalmol 85:1316, 2001; Tornambe PE: Macular hole genesis: the hydration theory. Retina
23:421, 2003; Tornambe PE et al: Definition of macular hole surgery end points: elevated/open, flat/open, flat/closed.
Retina 18:286, 1998; Tornambe PE et al: Macular hole surgery without face-down positioning. A pilot study. Retina
17:179, 1997; Verma D et al: Evaluation of posturing in macular hole surgery. Eye 16:701, 2002.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. The following has been disclosed:
Dr. Miller has a financial interest in STAAR Surgical Company and is a consultant for Alcon, Inc. and Hoya Corporation
USA. Dr. Bylsma is a consultant for STAAR Surgical Company.
Drs. Miller, Tornambe, and Bylsma were recorded at the 23rd Annual Current Concepts in Ophthalmology, held July 16,
2005, in San Diego, and sponsored by the San Diego Eye Bank. The Audio-Digest Foundation thanks Drs. Miller, Tornambe,
and Bylsma and the San Diego Eye Bank for their cooperation in the production of this program.
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