Relief of Intraocular Pressure by Applying Pressure on the Posterior Scleral Wound

Dr. Shepard writes a weekly information column ("Eye Care") for various newspapers that mentions numerous advances in ophthalmology, including RK. He is often quoted in the media regarding these advances. He has written a monograph ("Know Your Eyes") that provides ophthalmic information and answers to his patients' questions. This information is similar to that found in the American Academy of Ophthalmology brochures that one can purchase and give to one's patients. If giving your patient information about an ophthalmic problem or procedure is "advertising," as Dr. Cravy would have you believe, then we are all engaged in advertising. Richard E. Gwyn, Marketing Director

Shepard Eye Center Santa Maria, California

ANTERIOR CHAMBER LENSES To the Editor: This is to address the letters from Dr. Kenneth J. Hoffer (Anterior chamber lens terminology. ] Cataract Refract Surg 13:460,1987) and Dr. Charles D. Kelman (In defense of the Omnifit lens. ] Cataract Refract Surg 14:lO0, 1988). Dr. Hoffer's notation that the Kelman Omnifit "... is not as tolerant to improper sizing. . ." is a geometric truism. Flexible anterior chamber lenses have virtually eliminated sizing problems when implanted with haptic diameters that are equal to or greater than chamber diameters. Regardless, whenever haptic diameter is less than chamber diameter, precisely the same geometric facts apply to flexible as to fixed length lenses, and an undersized tripod is a decided second to an undersized tetrapod for achievement of fixation. l With our current preference for posterior chamber lenses, it is still important to remain mindful of the distinguishing characteristics of anterior chamber lenses, for which a need will always exist, and to be aware of the past experiences of Choyce and others concerning anterior chamber lens stability.2,3 As tetrapods, both the Kelman M ultiflex I and Multiflex II designs afford greater probabilities of proper fixation than any tripod. The Multiflex II obviates the possibility of pupillary capture of the optic-as Dr. Hoffer indicates-and in extolling the Multiflex II, his petition for its individual evaluation is both well-founded and an acknowledgment of Dr. Kelman's contributions to the evolution of an ideal anterior chamber lens. Richard

J.

Broggi, M. D.

Worcester, Massachusetts

REFERENCES 1. Broggi RJ: Choyce's postulate. Am Intra-Ocular Implant Soc J 11:272-278, 1985 350

2. Strampelli B: Tolerance of acrylic lenses in the anterior chamber in aphakia and refractive error. Atti Soc Oftal Lombarda 8:292, 1953 3. Choyce DP: The Mark VI, Mark VII and Mark VIII fixed-length all-acrylic StrampellilChoyce anterior chamber implants. J Soc Sci Med Lisbon 128:665, 1964

RELIEF OF INTRAOCULAR PRESSURE BY APPLYING PRESSURE ON THE POSTERIOR SCLERAL WOUND To the Editor: A common occurrence following cataract surgery is elevation of intraocular pressure. Problems are frequently encountered when using medication to lower the pressure in elderly patients. Accordingly, pressure can be applied to the posterior scleral wound after planned extracapsular surgery and to the posterior lip of the stab incision after phacoemulsification. For phacoemulsification, a needle or any sharp instrument is simply placed on the anesthetized eye immediately posterior to the incision, and slight, gentle pressure is applied without entering the wound itself. This gentle pressure allows fluid to flow out of the eye and not into the eye. Concerns about infection have been voiced; however, we have not noticed any problems and do not expect any to occur since there is a normal leakage of aqueous from the wound in the first several days following surgery. This method simply allows the surgeon control of the aqueous egress. In summary, placing slight pressure on the posterior scleral wound between sutures from planned extracapsular surgery or on the stab incision from phacoemulsification allows release of intraocular pressure without use of glaucomatous medications. James P. Gills, M.D. Tarpon Springs, Florida

EMPIRICAL MODIFICATION OF THE THEORETICAL IOL POWER FORMULAS To the Editor: Intraocular lens power formulas have previously been constructed using two different approaches: a theoretical approach and an empirical one. Each of these formulas comprises various terms of axial length and corneal power, combined with some constants. Theoretical formulas use the nonlinear terms of axial length and corneal power, in combination with theoretical constants. The ability of these formulas to adjust to clinical results is limited. On the other hand, empirical formulas comprise mostly linear terms. The constants used in these formulas are obtained by statistical analysis and their ability to be modified is

J CATARACT REFRACT SURG-VOL

14, MAY 1988