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Functional outcomes of acrylic IOLs in pediatric cataract surgery
LETTERS
3. Gaskell A, McLaughlin A, Young E, McCristal K. Direct optometrist referral of cataract patients into a pilot onestop cataract surgery facility. J R Coll Surg Edinburgh 2001; 46:133–137 4. Hughes E, Dimond J. Letter. Eye 2002; 16:667
2. Mu¨llner-Eidenbo¨ck A, Amon M, Moser E, et al. Morphological and functional results of AcrySof intraocular lens implantation in children: prospective randomized study of age-related surgical management. J Cataract Refract Surg 2003; 29:285–293
Functional outcomes of acrylic IOLs in pediatric cataract surgery
Preoperative LASIK screening: An evolving standard of care
W
he risk for keratectasia after laser in situ keratomileusis (LASIK) is a major concern to all refractive surgeons and is especially daunting when no preoperative warning signs manifest themselves. Thus, I found the case report on bilateral keratectasia after unilateral LASIK1 of particular interest. The authors’ premise is that preoperative screening for this patient was negative for forme fruste keratoconus (FFKC) or corneal instability by history, preoperative examination, and corneal topography. However, the preoperative EyeSys corneal topography map of the right cornea (Figure 1) clearly shows a small degree of inferior steepening, asymmetric astigmatism, and nonorthogonal astigmatism. The map of the left eye also demonstrates asymmetric astigmatism. Admittedly, these are subtle, soft signs of FFKC in the absence of other findings such as a K-reading greater than 47 diopters, pachymetry less than 500 mm, and an inferior–superior value greater than 1.4,2 but they suggest a less than perfectly normal cornea in this patient. By 2000–2003 preoperative screening standards, these subtle changes could justifiably be overlooked, especially with all other findings normal including no family history of keratoconus and best spectacle-corrected visual acuity of 20/20 or better. However, in 2004, these subtle changes are enough to suggest further topographic testing, such as examination of posterior float with, for example, the Orbscan II and specific keratoconus analyses with software packages available on current topography units such as keratoconus indices with the Tomey unit and Pathfinder Corneal Analysis with Zeiss-Humphrey topography units.3 In addition, the authors conclude that ‘‘in light of the normal postoperative posterior float and thickness maps, it (the Orbscan) would likely not have revealed a primary disorder’’ had it been performed preoperatively. In reality, the posterior float as noted in the postoperative Orbscan (Figure 5) is not normal.
e were very interested in the article by Raina and coauthors1 since we have been actively involved in managing pediatric cataracts for the past few years. The authors’ recommendation of performing a primary continuous curvilinear capsulorhexis (PCCC) in all patients older than 7 years is not in agreement with our experience. There cannot be 1 procedure for all age groups since the behavior of eyes in the preschool age group is different than that in other pediatric age groups. We perform PCCC in patients older than 7 years when significant postoperative inflammation is anticipated or in eyes that have a thick membrane adherent to the posterior capsule following trauma. Postoperative inflammation is directly related to posterior capsule opacification (PCO) formation. This has been our experience and is supported by a prospective study by Mu¨llner-Eidenbo¨ck et al.2 Research needs to be directed toward identifying cases that have a higher propensity for developing PCO, and performing PCCC in all patients older than 7 years should be avoided. Moreover, leaving the posterior capsule intact reduces the surgical time, and the complications related to posterior segment are avoided. In the study, 1 important surgical aid that is conspicuous by its absence is the use of trypan blue dye 0.1% for staining the anterior capsule. The dye is inexpensive and by enhancing the capsular visibility, it helps to achieve a higher rate of optimal capsulorhexis size, shape, and centration. In our experience, the dye also aids in visualization of the posterior capsule during PCCC. SUDARSHAN KHOKHAR, MD HARPREET SINGH, MD New Delhi, India
Reference 1. Raina UK, Mehta DK, Monga S, Arora R. Functional outcomes of acrylic intraocular lenses in pediatric cataract surgery. J Cataract Refract Surg 2004; 30:1082–1091 1084
T
J CATARACT REFRACT SURG—VOL 31, JUNE 2005
3. Gaskell A, McLaughlin A, Young E, McCristal K. Direct optometrist referral of cataract patients into a pilot onestop cataract surgery facility. J R Coll Surg Edinburgh 2001; 46:133–137 4. Hughes E, Dimond J. Letter. Eye 2002; 16:667
2. Mu¨llner-Eidenbo¨ck A, Amon M, Moser E, et al. Morphological and functional results of AcrySof intraocular lens implantation in children: prospective randomized study of age-related surgical management. J Cataract Refract Surg 2003; 29:285–293
Functional outcomes of acrylic IOLs in pediatric cataract surgery
Preoperative LASIK screening: An evolving standard of care
W
he risk for keratectasia after laser in situ keratomileusis (LASIK) is a major concern to all refractive surgeons and is especially daunting when no preoperative warning signs manifest themselves. Thus, I found the case report on bilateral keratectasia after unilateral LASIK1 of particular interest. The authors’ premise is that preoperative screening for this patient was negative for forme fruste keratoconus (FFKC) or corneal instability by history, preoperative examination, and corneal topography. However, the preoperative EyeSys corneal topography map of the right cornea (Figure 1) clearly shows a small degree of inferior steepening, asymmetric astigmatism, and nonorthogonal astigmatism. The map of the left eye also demonstrates asymmetric astigmatism. Admittedly, these are subtle, soft signs of FFKC in the absence of other findings such as a K-reading greater than 47 diopters, pachymetry less than 500 mm, and an inferior–superior value greater than 1.4,2 but they suggest a less than perfectly normal cornea in this patient. By 2000–2003 preoperative screening standards, these subtle changes could justifiably be overlooked, especially with all other findings normal including no family history of keratoconus and best spectacle-corrected visual acuity of 20/20 or better. However, in 2004, these subtle changes are enough to suggest further topographic testing, such as examination of posterior float with, for example, the Orbscan II and specific keratoconus analyses with software packages available on current topography units such as keratoconus indices with the Tomey unit and Pathfinder Corneal Analysis with Zeiss-Humphrey topography units.3 In addition, the authors conclude that ‘‘in light of the normal postoperative posterior float and thickness maps, it (the Orbscan) would likely not have revealed a primary disorder’’ had it been performed preoperatively. In reality, the posterior float as noted in the postoperative Orbscan (Figure 5) is not normal.
e were very interested in the article by Raina and coauthors1 since we have been actively involved in managing pediatric cataracts for the past few years. The authors’ recommendation of performing a primary continuous curvilinear capsulorhexis (PCCC) in all patients older than 7 years is not in agreement with our experience. There cannot be 1 procedure for all age groups since the behavior of eyes in the preschool age group is different than that in other pediatric age groups. We perform PCCC in patients older than 7 years when significant postoperative inflammation is anticipated or in eyes that have a thick membrane adherent to the posterior capsule following trauma. Postoperative inflammation is directly related to posterior capsule opacification (PCO) formation. This has been our experience and is supported by a prospective study by Mu¨llner-Eidenbo¨ck et al.2 Research needs to be directed toward identifying cases that have a higher propensity for developing PCO, and performing PCCC in all patients older than 7 years should be avoided. Moreover, leaving the posterior capsule intact reduces the surgical time, and the complications related to posterior segment are avoided. In the study, 1 important surgical aid that is conspicuous by its absence is the use of trypan blue dye 0.1% for staining the anterior capsule. The dye is inexpensive and by enhancing the capsular visibility, it helps to achieve a higher rate of optimal capsulorhexis size, shape, and centration. In our experience, the dye also aids in visualization of the posterior capsule during PCCC. SUDARSHAN KHOKHAR, MD HARPREET SINGH, MD New Delhi, India
Reference 1. Raina UK, Mehta DK, Monga S, Arora R. Functional outcomes of acrylic intraocular lenses in pediatric cataract surgery. J Cataract Refract Surg 2004; 30:1082–1091 1084
T
J CATARACT REFRACT SURG—VOL 31, JUNE 2005