Cataract Surgery

Educational Objectives

The goal of this program is to improve the management of complications during cataract surgery. After hearing and assimilating this program, the clinician will be better able to:

1. Manipulate surgical instruments to improve efficacy and safety during cataract surgery.
2. Use viscoelastic to pressurize the eye appropriately at various stages of surgery.
3. Manage risk factors during preoperative planning to reduce likelihood of complications.
4. Create strategies to minimize trauma to the eye when surgical complications arise.
5. Develop techniques to prevent damage to the intraocular lens and the eye during implantation of the lens.

Summary

Optimization of Surgical Procedures

Instrumentation: start with a clean field; use transparent film dressing (Tegaderm) on top of the drape to secure eyelashes; sharp instruments should be inserted parallel to the iris; dull instruments should be inserted such that they are pointed toward the target site; insertion at the proper angle increases surgical efficiency and safety; proper insertion of instruments prevents damage to Descemet membrane or the anterior capsule; the corneal incision should be the smallest needed to perform the surgery; the phacoemulsification (phaco) probe should fit snugly within the incision; lateral movement of instruments should be avoided because it can enlarge the incision site, which causes more fluid to leak out and destabilizes the anterior chamber (AC); persistent focal edema can occur in areas where Descemet membrane is disturbed; instrument should be inserted completely before injections, particularly of viscoelastic agents, to avoid detachment of Descemet membrane

Capsulorhexis: the instrument should be aimed at the center of the anterior capsule; inserting the needle too deep disrupts the cortex; if the needle is too superficial, formation of the flap is difficult; the needle should be inserted 10% to 90% of the way and moved in a C shape to form the flap; when the flap is folded down, grasping the fold should be avoided because it causes the capsulorhexis to go out; grasping the flap close to the fold allows for better control; when using angled ophthalmic forceps (eg, Utrata forceps), the tips should be kept closed until they are in the correct position to grasp the flap; the AC should be highly pressurized during capsulorhexis; injected viscoelastic should be sufficient to place tension on the anterior capsule

Hydrodissection: the AC should be soft to allow room for fluid to move; excessive pressure in the AC during this step can cause rupture of the posterior capsule or iris prolapse; after capsulorhexis, apply pressure on the wound to release some viscoelastic and reduce pressure before hydrodissection

Techniques to improve access within the eye: pushing on a wound to access an area releases too much viscoelastic, which causes corneal striae and reduces visibility; therefore, instruments should be pivoted (not pushed) in the eye; the instruments should be held and moved in directions to keep the eye as stationary as possible; in general, it is important to have a secondary plan and avoid attempting any action more than 3 times

Division of the nucleus: in the divide-and-conquer technique, sculpting involves cutting the nucleus without occlusion; the phaco setting 3 or irrigation setting 1 are preferred; the nucleus should be cut through, rather than pushed on, and complete occlusion should be avoided; if the nucleus is moving, use more power or move slower (particularly if the nucleus is hard); most phaco systems have automatic settings based on density of the lens; when cracking the nucleus, the instruments should be inserted as deep as possible into the groove without touching the bottom; use small, horizontal movements to open up the nucleus; find a ledge to hold to prevent the instruments from moving from their original position while cracking

Nucleus removal: the phaco tip should be positioned at the triangular tip of the quadrant during removal; the goal is to achieve a soft occlusion in which the tip is holding onto the quadrant without excessive aspiration; use position 2 on the phaco system for soft lenses and position 3 for dense lenses; once occlusion is achieved, the quadrant may be slowly lifted into the AC; before emulsification, ensure the quadrant is completely inside of the AC, the eye is in primary position, and the second instrument is positioned under the phaco probe; moving too quickly can result in loss of occlusion, which releases the hold on the quadrant; attempting emulsification before the quadrant is completely inside of the AC can result in aspiration of the anterior or posterior capsule; ensure the position of the second instrument does not interfere with removal of the piece; avoid bumping the phaco probe into the second instrument while lifting the quadrant; once the quadrant is inside of the AC, move the second instrument into the safety position (a few millimeters under the tip of the phaco probe); with this strategy, the second instrument prevents the posterior capsule from protruding forward during removal of the nucleus; occlusion may be achieved with other methods if necessary; if the lens is soft, hold the epinucleus on a gentle 2 setting of the phaco probe and lift the nucleus; if the lens is dense, use the second instrument to lift the piece up and the probe to grasp the bottom of the piece (rather than grasping it from the top)

Positioning: the eye should be maintained in the primary position because rotation of the eye changes the anatomy; the center of the eye is the ideal site for removal of the nucleus because it is located furthest from the posterior capsule and endothelium; working in the peripheral portions of the eye, which can occur when the eye is not in primary position, increases the risk for damage to the endothelium, anterior capsule, and posterior capsule; the probe should be held in the center of the eye to allow it to aspirate the fragments of the nucleus; avoid chasing fragments into the angle or other areas where the endothelium may be damaged

Cortex removal: the goal is to achieve complete occlusion by placing the tip of the probe in the center of a triangular piece rather than placing it in the strands of the cortex; moving back and forth in a tangential motion before pulling in radially toward the center of the eye reduces stress on the zonules; as with nucleus removal, the probe should be placed in the center of the eye while avoiding the periphery

Placement of the intraocular lens (IOL): IOLs should be handled minimally because surgical instruments can cause permanent scratches; use viscoelastic to fill the capsule 180 degrees away from the wound; the AC should not be deep to allow for easy access to the equator; angle the IOL toward the equator (180 degrees away); once one-half of the IOL is in the bag and one-half is in the AC, use the angled IOL hook (Sinskey hook) to gently rotate the IOL into position; these steps ensure the haptics are inside of the bag; for nontoric IOLs, aim for the 12- and 6-o’clock position; multifocal IOLs should be slightly decentered nasally

Management of Complications During Surgery

Preoperative planning: address corneal conditions (eg, scarring) prior to surgery if keratometry readings may be affected; identify potential issues with the AC (eg, shallow AC) and anatomy (eg, weak zonules from prior trauma, pseudoexfoliation, poor dilation, dense lenses); tamsulosin and other drugs for benign prostatic hyperplasia can cause intraoperative floppy iris syndrome

Wound construction: enter the eye parallel to the iris to avoid injury to the anterior capsule; avoid lateral movements, which can enlarge the wound; a short wound may not seal well and increases the risk for iris prolapse; a long wound may induce corneal striae, which can obscure the view during surgery; the wound should be created at the limbus because the wound can induce astigmatism if it is located too centrally; avoid hitting the conjunctiva with the back edge of the keratome because fluid can enter underneath and cause elevation of the conjunctiva; formation of a bulla minifies the surgeon’s view and creates an unstable concave lens, which makes surgery more challenging; if the conjunctiva is hit, the surgery can be completed quickly before the bulla forms or the conjunctiva can be cut to release fluid

Complications of the capsule: with intumescent cataracts, staining the capsule with trypan blue improves visibility; the Argentinian flag sign occurs when the anterior capsule is cut, which leads to formation of a tear extending from each edge; this complication tends to occur when the anterior capsule is under pressure and bows forward due to the intumescent cataract; prevention in high-risk eyes — pressurizing the eye with viscoelastic to flatten the anterior capsule can prevent this problem; additionally, the cystotome can be used to remove some of the cortex and decompress the nucleus; femtosecond laser can also be used to create the capsulorhexis quickly; intraoperative management — the Argentinian flag sign may occur in eyes with no risk factors if an instrument inadvertently cuts the anterior capsule and viscoelastic or balanced salt solution enters the nucleus; if the Argentinian flag sign occurs, enlarge the capsulorhexis, avoid hydrodissection, perform sculpting and cracking, and bring the nucleus fragment into the AC away from the unstable capsule; viscoelastic can be used to stabilize the capsule

Complications of the iris: releasing pressure in the AC before hydrodissection is recommended to avoid iris prolapse; if prolapse occurs, avoid pushing the iris back through the wound; instead, the second port should be used to sweep the iris back, and surgery can be continued with caution; strategies to minimize trauma to a prolapsed iris during surgery include minimizing insertion and removal of instruments, adding more buffered lidocaine solution (Shugarcaine), or use of an iris hook to stabilize the iris; if a poorly dilating iris is identified ahead of time, a pupil expansion ring (Malyugin ring) can be used prior to capsulorhexis; capturing 3 prongs upon initial entrance (the prong furthest away and the 2 prongs on the sides) is ideal; use a second instrument to release the pupil expansion ring from the applicator before exiting the site, and secure the last prong (the prong closest to the surgeon); capturing fewer prongs on initial entrance results in a need for further manipulation to secure the ring; when removing the pupil expansion ring, release all prongs into the AC before grasping the closest prong to extract the ring; if all of the prongs are not released first, the ring can slip under the iris and catch the anterior capsule

Zonular complications: a visible equator indicates that no zonules are present and the capsule has contracted; zonular trauma can occur during irrigation and aspiration; pulling on the anterior capsule can cause focal dehiscence in the zonules; to prevent this complication, the cortex should be held in the area most likely to have complete occlusion (not near the anterior capsule); to minimize zonular complications during insertion of the IOL, fill the bag with viscoelastic, maintain a shallow AC, and angle the IOL 180 degrees away; if the bag is shallow and the IOL is angled too vertically during insertion, dehiscence of the zonules can occur when pushing the IOL into position; a capsular tension ring (CTR) should be ready in case of focal zonular trauma; use viscoelastic to expand the area before inserting the CTR into the bag; the CTR should be angled so that the opening is in a different area than the zonular dehiscence; if complications are anticipated, use iris hooks or capsule hooks to stabilize the capsule; use viscoelastic in the area of zonular loss to prevent prolapse of vitreous; if zonular trauma extends >4 clock hours, suturing of capsular tension segments may be necessary

Complications of the posterior capsule: rupture of the posterior capsule can occur during hydrodissection (particularly through the paracentesis) and when using the phaco probe; a rupture may be identified through sudden dilation of the iris, appearance of a bright red reflex, or a change in fluid dynamics (indicating vitreous in the AC); if a rupture occurs, a second instrument should be used to push the vitreous back before removing the phaco probe, followed by slow removal of accessible nuclear fragments; avoid using the phaco probe to remove fragments from the vitreous cavity; addition of viscoelastic where the posterior capsule is compromised stabilizes the area; once nucleus removal is complete, suture the wound and create a second paracentesis for vitrectomy

Vitreous removal: use preservative-free triamcinolone to highlight the vitreous; the cut I/A setting is used to remove vitreous from the AC, followed by the I/A cut setting with the cutter off (which functions as the I/A setting on the phaco machine); the cortex is removed once the vitreous in the AC is cleared; the vitrector should be positioned lower than the irrigation; if the rupture is visible, place the vitrector directly into the hole; the goal is to remove all vitreous from the AC, but complete removal from the vitreous cavity is unnecessary; removal of vitreous from a posterior approach may be considered, particularly if zonular dehiscence is present

Complications of the AC: if the AC remains shallow and does not deepen with viscoelastic, a choroidal hemorrhage, ruptured capsule, or iris block should be suspected; if the eye is at high risk for posterior vitreous pressure, adjust the speculum to avoid placing pressure on the vitreous; use of mannitol may be considered for small eyes; if the eye is at high risk, decompression of the eye with a dry vitrectomy should be considered prior to cataract surgery and significantly decreases the complexity of surgery

Issues with IOLs: one-piece acrylic IOLs are flexible and can flip around in the eye, particularly if viscoelastic is removed before the haptics are fully opened; in poorly dilated eyes, one-half of the lens may land in the bag and one-half in the sulcus; when removing viscoelastic, a decentered IOL indicates that one haptic is in the bag and one is in the sulcus; angling the IOL toward the equator (180 degrees away from the surgeon) such that the leading haptic lands in the bag can prevent this issue; once viscoelastic is removed, check again to ensure both haptics are in the bag by looking for centration and a full circle of the capsulorhexis above the IOL; a malpositioned IOL should be suspected in a patient with uveitis-glaucoma-hyphema (UGH) syndrome or pigment in the AC after uncomplicated cataract surgery

Pearls for implantation of IOL: inform patients desiring multifocal IOLs that a one-piece IOL may need to be substituted if the eye anatomy is not as expected during surgery; a 3-piece IOL can be manually folded during placement, but grasping the haptics should be avoided because they can become damaged; when the leading haptic is in position, hold the trailing haptic at the edge for optimal manipulation; manually folding the IOL can provide better control over placement compared with use of cartilage to inject the IOL, but the method used depends on personal preference

Anterior chamber IOL (ACIOL): ensure that the vault of the ACIOL is facing the surgeon; placing the ACIOL backwards pushes on the iris, which may cause UGH syndrome; when placing an ACIOL, avoid dragging the iris prematurely; to avoid this issue, an IOL glide (Sheets glide) may be used to guide the ACIOL to the angle; when positioning the ACIOL, compress the haptics and rotate the ACIOL until it is 90 degrees away from the wound; peripheral iridotomy (PI) should be performed after positioning the ACIOL because placing the PI beforehand can interfere with positioning of the ACIOL; if the ACIOL is not rotated, the subincisional haptic may not be flush with the angle; malpositioning of the IOL causes inflammation, pigment release, and UGH syndrome; suture all wounds after performing vitrectomy

Readings

Aaronson A, Viljanen A, Kanclerz P, et al. Cataract complications study: an analysis of adverse effects among 14,520 eyes in relation to surgical experience. Ann Transl Med. 2020 Nov;8(22):1541; Adams ML, Diakonis VF, Weinstock RJ. Argentinian flag sign and its management during femtosecond laser-assisted cataract surgery in a case with intumescent cataracts. Case Rep Ophthalmol. 2021 Apr;12(1):129-133; Chen Y, Cao Q, Xue C, et al. Comparison of two techniques for toric intraocular lens implantation: hydroimplantation versus ophthalmic viscosurgical devices. BMC Ophthalmol. 2018 Apr;18(1):109; Christou CD, Tsinopoulos I, Ziakas N, et al. Intraoperative floppy iris syndrome: updated perspectives. Clin Ophthalmol. 2020;14:463-471; Durr GM, Ahmed IIK. Intraocular lens complications: decentration, uveitis-glaucoma-hyphema syndrome, opacification, and refractive surprises. Ophthalmology. 2021 Nov;128(11):e186-e194; Galor A, Goldhardt R, Wellik SR, et al. Management strategies to reduce risk of postoperative infections. Curr Ophthalmol Rep. 2013;1(4):10.1007/s40135-013-0021-5. doi:10.1007/s40135-013-0021-5; Hong AR, Sheybani A, Huang AJ. Intraoperative management of posterior capsular rupture. Curr Opin Ophthalmol. 2015 Jan;26(1):16-21; Jasinskas V, Vaiciuliene R, Varoniukaite A, et al. Novel microsurgical management of uveitis-glaucoma-hyphema syndrome. Int Ophthalmol. 2019 Jul;39(7):1607-1612; Malyugin B. Cataract surgery in small pupils. Indian J Ophthalmol. 2017 Dec;65(12):1323-1328; Mohammadpour M, Erfanian R, Karimi N. Capsulorhexis: pearls and pitfalls. Saudi J Ophthalmol. 2012 Jan;26(1):33-40; Negretti GS, Lai M, Petrou P, et al. Anterior chamber lens implantation in vitrectomised eyes. Eye (Lond). 2018 Mar;32(3):597-601; Park J, Yum HR, Kim MS, et al. Comparison of phaco-chop, divide-and-conquer, and stop-and-chop phaco techniques in microincision coaxial cataract surgery. J Cataract Refract Surg. 2013 Oct;39(10):1463-1469; Patel RH, Karp CL, Yoo SH, et al. Cataract surgery after refractive surgery. Int Ophthalmol Clin. 2016 Spring;56(2):169-180.

Disclosures

For this program, members of the faculty and planning committee reported nothing relevant to disclose.

Acknowledgements

Dr. Galor was recorded exclusively for Audio Digest on October 28, 2021, using virtual teleconference software. Audio Digest thanks Dr. Galor for her cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0 CE contact hours.

Lecture ID:

OP600901

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.