Management of lens–iris diaphragm retropulsion syndrome

We read with interest the case report by Cionni and coauthors1 describing a method of managing LIDRS during phacoemulsification. Using microendoscopy, they observed that LIDRS was essentially a reverse pupillary block and could be managed by separating the iris from the anterior capsule rim mechanically with an irrigation/aspiration tip. We also encounter lots of high myopic phacoemulsification in our locality and would like to share our experience in tackling the problem of LIDRS. When the AC deepens in LIDRS, the surgeon's reflexive action is to lower the infusion bottle height. The decrease in pressure acting on the lens also causes an undesirable reduction in infusion volume. When outflow equals or outstrips inflow, AC turbulence and minicollapses occur and mimic phenomena commonly seen with positive pressure.2 By lifting the iris rim from the residual anterior capsule rim, the reverse pupillary block can be relieved, but the effect may be temporary as the underlying causes such as thinly stretched zonules, underdeveloped ciliary body, and disequilibrium in pressures between chambers are still present. All will result in the fluctuation of AC depths and oscillation of pupil sizes, which may make the surgery difficult and hazardous. We prefer to relieve the reverse pupillary block in a more sustained manner intraoperatively using flexible iris retractors developed by de Juan and Hickingbotham.3 Three of the iris retractors (Alcon/Grieshaber flexible iris retractors 611.65) are inserted, as described by Nichamin,4 and the fourth is placed in the subincisional area just posterior to the corneal phaco incision, as described by Oetting and Omphroy,5 to create a diamond-shaped pupil. By doing this, the iris can be lifted up continuously from the anterior capsule rim to avoid reverse pupillary block and the iris can also be held securely from the wound and phaco probe to minimize the chance of iris prolapse and damage. Alternatively, the reverse pupillary block can be relieved by enlarging the existing continuous curvilinear capsulorhexis (CCC). A small flap at the rim of CCC is created with the cystotome by making a tangential cut and can be grasped and extended with a capsulorhexis forceps. A 7.0 to 8.0 mm diameter CCC is generally large enough to avoid iris–capsule touch. This method is technically more demanding but can be considered a substitute when an iris retractor is not available. We commend Cionni and coauthors for their work. We hope that our experience and suggestions can supplement their described method and enhance the overall results in handling LIDRS. Vincent Y.W. Lee FRCS David T.L. Liu MRCS Wai-Man Chan FRCS Dennis S.C. Lam FRCS, FRCOphth Hong Kong, China