Severe iridodialysis from phacoemulsification tip suction Tetsuro Oshika, MD, Shiro Amano, MD, Satoshi Kato, MD ABSTRACT During cataract surgery, the iris of an 83-year-old woman was strongly sucked into the phacoemulsification tip twice, resulting in severe iridodialysis. The dehisced iris was sutured to the sclera using double-armed 10-0 polypropylene on a long curved needle. Intensive suction of the iris by the phacoemulsification tip can lead to severe iridodialysis. Machine setting parameters, particularly flow rate, should be lowered after the first iris suction to avoid further iris damage. J Cataract Refract Surg 1999; 25:873– 875 © 1999 ASCRS and ESCRS
ridodialysis can occur after blunt trauma to the globe1 or surgical manipulation, such as removal of a closedloop anterior chamber intraocular lens (IOL).2 To our knowledge, there has been no report of severe iridodialysis during phacoemulsification. We report a new form of iridodialysis and discuss its underlying causes.
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Case Report An 83-year-old woman had phacoemulsification in the left eye. The mydriasis was slightly insufficient, with a maximum pupillary diameter of approximately 7.5 mm. After a 3.0 mm temporal clear corneal incision was created, continuous curvilinear capsulorhexis and hydrodissection were performed. Using the phaco chop technique, the nucleus was cracked and phacoemulsification initiated by aspirating the central epinucleus. During removal of the first quadrant, the nasal iridial margin was sucked into the phacoemulsification tip. The iris was quickly released from the tip upon termination of the aspiration. The setting parameters of the Prestige
Accepted for publication January 27, 1999. From the Department of Ophthalmology, University of Tokyo School of Medicine, Tokyo, Japan. None of the authors has a commercial or proprietary interest in any product or company mentioned. Reprint requests to Tetsuro Oshika, MD, Department of Ophthalmology, University of Tokyo School of Medicine, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655 Japan. © 1999 ASCRS and ESCRS Published by Elsevier Science Inc.
phacoemulsifier (Allergan Medical Optics) were as follows: vacuum level 300 mm Hg, flow rate 28 mL/min, ultrasound power 60%, and bottle height 70 cm. These parameters were not modifed after the first suction of the iris. During removal of another quadrant, the second and major suction of the iris into the phacoemulsification tip occurred, causing severe iridodialysis extending from 7 to 11 o’clock (Figures 1and 2). Using a second hand hook, the iris was liberated from the phacoemulsification tip. The vacuum level was decreased to 180 mm Hg and the flow rate lowered to 22 mL/min. The nuclear fragments and cortical material were removed by pressing and holding the dehisced iris with a hook. An acrylic foldable IOL (Alcon MA60BM) was then implanted in the capsular bag. Significant pupillary deformation was not seen when the anterior chamber was filled with viscoelastic material. However, once the viscoelastic material was washed out and replaced with balanced salt solution, pupillary decentration became remarkable. The authors repaired the iridodialysis using a double-armed 10-0 polypropylene McCannell suture with a long curved needle (PC-9, Alcon Laboratories Inc.). The suturing method was similar to those reported previously.3,4 Peritomy was placed at 3 o’clock. Along with viscoelastic material infusion into the anterior chamber, the first needle entered the anterior chamber through the temporal corneal incision, penetrated the base of the iris, and exited through the chamber angle and sclera (Figures 3 and 4). The second needle entered the anterior chamber through the same entry site, went over the iris, and exited through the sclera. Both sutures were tied episclerally, and the knot was rotated and buried in the sclera. The conjunctiva was reapproximated in the usual 0886-3350/99/$–see front matter PII S0886-3350(99)00042-5
CASE REPORTS: OSHIKA
Figure 1. (Oshika) The nasal iris was strongly sucked into the
Figure 2. (Oshika) Schematic of Figure 1.
phacoemulsification tip twice, causing severe iridodialysis from 7 to 11 o’clock. The phacoemulsification tip is shown entering the chamber from the temporal corneal incision of the left eye.
Figure 3. (Oshika) Using a double-armed 10-0 polypropylene X-
Figure 4. (Oshika) Schematic of Figure 3.
suture, the base of the dehisced iris is sutured to the sclera.
fashion. Postoperatively, the patient has maintained good iris position without complications (Figure 5).
Discussion
Figure 5. (Oshika) Slitlamp photograph of the eye 1 month after surgery.
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Because of tissue fraying and flaccidity, additional damage is difficult to avoid once the iris has been sucked into the phacoemulsification tip. In the current case, machine settings should have been changed after the first incident. In particular, the flow rate should have been lowered to reduce the risk of another suction. The high vacuum level setting was also partly responsible for the iris tearing while caught
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in the tip. When this complication occurs, the flow rate influences the aspiration of the iris into the tip, while the vacuum level determines the holding and tearing force exerted on the iris after suction.5 The fragility of this patient’s iris, confirmed when surgery was performed on the fellow eye 1 week later, may also have contributed to the current episode. Increasingly, cataract surgery is performed by phacoemulsification, and surgical techniques using high vacuum and flow rate settings are becoming popular. Surgeons should be aware that severe iridodialysis can occur from inappropriate parameter settings, inadequate surgical manipulation, and patients’ background conditions.
References 1. Nunziata BR. Repair of iridodialysis using a 17-millimeter straight needle. Ophthalmic Surg 1993; 24:627– 29 2. Kervick GN, Johnston SS. Repair of inferior iridodialysis using a partial-thickness scleral flap. Ophthalmic Surg 1991; 22:354 –355 3. Wachler BB, Krueger RR. Double-armed McCannell suture for repair of traumatic iridodialysis. Am J Ophthalmol 1996; 122:109 –110 4. Kaufman SC, Insler MS. Surgical repair of a traumatic iridodialysis. Ophthalmic Surg Lasers 1996; 27:963–966 5. Neuhann TF, Steinert RF. Instrumentation. In: Steinert RF, ed, Cataract Surgery: Technique, Complications, & Management. Philadelphia, PA, WB Saunders, 1995; 57– 67
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