Subconjunctival hemorrhages after LASIK

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such as Medline. We can assure Dr. Fugo that we will credit his contribution to this particular incision type in future publications related to this topic.—Walter Sekundo, MD, Thorsten Bo¨ker, MD, Rolf Fimmers, PhD

Proposal for Increased Accuracy in Wavefront-Guided LASIK

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he American Society of Cataract and Refractive Surgery provided an excellent summary and update of wavefront-guided refractive surgery (B. Fundingsland, ed, Surf’s Up: The New Refractive Paradigm of Wavefront Technology, EyeWorld, May 2000, pages 68 –72). I would like to propose a strategy for refining clinical results of wavefront-assisted laser in situ keratomileusis (LASIK). As Reinstein has demonstrated (C. Glenn, ed, Beyond Wavefront, Review of Ophthalmology, April 2000, page 51), results of even conventional LASIK are limited by unpredictable postoperative epithelial and biomechanical stromal changes that are unique to each patient’s healing characteristics. Clinical experience shows that the need for enhancement surgery, which could be characterized as a response to these unique epithelial and biomechanical changes, increases with increasing degrees of attempted correction: the more we sculpt with the laser, the more we tend to evoke idiosyncratic responses. Thus, conventional LASIK is unable to consistently achieve perfect correction of even the lower-order aberrations (sphere and cylinder). It is therefore likely that the more subtle effects of any corneal sculpting done to correct higher-level optical aberrations would be swallowed up by the idiosyncratic epithelial and biomechanical changes invoked by the correction of the cylinder and sphere. I propose that wavefront-guided LASIK, rather than being conceived of as an attempt to correct all Zernike coefficients with one treatment, be approached from a staged strategy. I propose that the first LASIK surgery would correct only the primary optical aberrations, the spherocylindrical error. I propose that a second surgery be performed with a standard LASIK enhancement technique 3 months later to “enhance” the higher-level optical aberrations. By first correcting the spherocylindrical error, the bulk of the laser sculpting 1570

would be addressed and most of the epithelial and biomechanical idiosyncratic responses to this sculpting would be allowed to run their course. After 3 months, once the eye has stabilized, the flap would be lifted and more subtle attention could then be applied to correcting higher-order optical aberrations without invoking as much healing response as if the higher-level errors were addressed at the same time as the spherocylindrical correction. In this way, the higher-order optical aberrations, including any aberrations induced by the initial LASIK procedure, could be addressed more precisely. This technique could be expected to take most optimal advantage of the information available from wavefront analysis and also of the extraordinary precision of the latest excimer laser systems. DAVID R. SHAPIRO, MD Ventura, California, USA

Subconjunctival Hemorrhages After LASIK

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aser in situ keratomileusis (LASIK) has become the surgery of choice for the correction of a wide variety of refractive errors.1–3 In addition to the various complications of LASIK reported in the literature,4 we noticed that a number of patients developed large subconjunctival hemorrhages after the procedure. Of 100 patients who had bilateral simultaneous LASIK at our center in the past 2 months, 31 developed significant subconjunctival hemorrhages. None of the patients had a history of diabetes, hypertension, or any other systemic vascular or hematological disorder. Laser in situ keratomileusis was performed with the Chiron Technolas 217 excimer laser using the Hansatome microkeratome. Although subconjunctival hemorrhage may be a common occurrence, its significance has not been discussed as a complication of LASIK surgery. A subconjunctival hemorrhage is not an important complication for the refractive surgeon. However, the patient and his or her relatives may perceive it as a serious intraoperative complication. In addition, it causes a serious embarrassment to patients who have been assured they can resume their routine work on the next postoperative day. In our experience in India, a number of patients have LASIK for important social events in the immediate future and prefer that the knowledge of their

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operation not be made public. In such patients, a large subconjunctival hemorrhage may seriously inconvenience the patient and bring disrepute to the operating surgeon. All patients having LASIK should be educated about this complication, and it should be mentioned in the consent form. Reducing the suction time may help to prevent this complication. TANUJ DADA, MD NAMRATA SHARMA, MD RASIK B. VAJPAYEE, MBBS, MS VIJAY K. DADA, MBBS, MS New Delhi, India

References 1. Pallikaris IG, Papatzanaki ME, Stathi EZ, et al. Laser in situ keratomileusis. Lasers Surg Med 1990; 10:463– 468 2. Gimbel HV, Basti S, Kaye GB, Ferensowicz M. Experience during the learning curve of laser in situ keratomileusis. J Cataract Refract Surg 1996; 22:542–550 3. Pe˜rez-Santonja JJ, Bellot J, Claramonte P, et al. Laser in situ keratomileusis to correct high myopia. J Cataract Refract Surg 1997; 23:372–385 4. Gimbel HV, Penno EE, van Westenbrugge JA. Incidence and management of intraoperative and early postoperative complications in 1000 consecutive laser in situ keratomileusis cases. Ophthalmology 1998; 105:1839 –1847; discussion by TC Clinch, 1847–1848

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