- Email: [email protected]
Recurrent capsule opacity and erythropoietin
CORRESPONDENCE
the left eye received ⫹2.00 ⫹2.50 ⫻ 180 instead of the planned correction. Postoperatively, the UCVA in the right eye was emmetropia (1.0); in the left eye, it was 0.2 with a refraction of ⫹2.50 ⫺5.50 ⫻ 180 and the BCVA was 0.8. The corneal pachymetry was 590 m in the right eye and 585 m in the left eye, and the keratometry was 44.00/46.25 D and 42.75/47.75 D, respectively. Three months after the LASIK procedure, reintervention was done using the cross-cylinder technique: ⫺2.50 ⫻ 180 and ⫹3.00 ⫻ 90. Three months later, the UCVA improved to 0.9, the pachymetry was 550 m, and the keratometry reading was 44.00/46.50 D. Case 3 A 36-year-old man was referred to the refractive unit with a BCVA of 1.0 and a refraction of ⫹2.00 ⫺2.00 ⫻ 5 in the right eye and 0.7 and a refraction of ⫹4.50 ⫺5.25 ⫻ 170 in the left eye. The pachymetry was 515 m and 510 m, respectively, and the keratometry, 41.25/43.50 D and 40.00/44.75 D, respectively. Laser in situ keratomileusis was performed to target emmetropia as follows: ⫹2.00 ⫻ 95 in the right eye and ⫺0.75 ⫹5.25 ⫻ 170 instead of ⫺0.75 ⫹5.25 ⫻ 80 in the left eye. One month after LASIK, the UCVA was 0.9 and the BCVA was 1.0 with ⫹0.5 ⫺0.5 ⫻ 90 in the right eye and less than 0.05 and 0.6 with ⫹7.0 ⫺10.0 ⫻ 170 in the left eye. The pachymetry was 514 m and 480 m, respectively. The keratometry was 42.50/ 42.75 D in the right eye and 38.00/49.25 D in the left eye. Astigmatic keratotomy was performed in the left eye in a trial to decrease the iatrogenic astigmatism. Three months after the AK, the UCVA was 0.1 and the BCVA, 0.9 with ⫹3.00 ⫺5.00 ⫻ 180. The keratometry was 39.25/46.00 D and at this point, re-LASIK was performed using the cross-cylinder technique: ⫺2.00 ⫻ 180 and ⫹3.00 ⫻ 90. Two months after the re-LASIK procedure, the UCVA was 1.0 bilaterally. The pachymetry was 514 m in the right eye and 430 m in the left eye. The keratometry was 42.75/43.00 D and 41.00/44.00 D, respectively.
Discussion One major problem in LASIK practice is inaccurate orientation of the ablation profile because of inadequate preoperative evaluation or feeding incorrect data into
the laser. This problem will lead to the development of induced astigmatism, which can be difficult to manage and lead to catastrophic visual impairment. Paying more attention to the process of handling patients’ data could prevent a long nightmare. Our cases developed induced astigmatism due to misreading the astigmatic axis in 1 case and to inputing the wrong axis in the other 2 cases. All the cases could be managed by using AK combined with re-LASIK or LASIK using the cross-cylinder technique. Although the outcomes were satisfactory, the effort and stress could have been prevented by meticulously reviewing each patient’s report before engaging the laser. If this error occurs with the resulting induced astigmatism, a combination of AK and cross-cylinder LASIK ablation can be effective when the corneal pachymetry is sufficient for the procedure. JOSE RODR´IGUEZ-PRATS, MD AHMED GALAL AHMED, MD Ma-JOSE AYALA, MD JORGE L. AL´IO, MD, PhD Alicante, Spain
Recurrent Capsule Opacity and Erythropoietin
T
here are no extensive case series of recurrent capsule opacity in uncomplicated senile cataract. Recurrences involve children, uveitis, or vitreoretinal pathology, not a routine case in patients over 60 years of age.1 In my last 2500 neodymium:YAG (Nd:YAG) laser capsulotomies, there were contractions that required treatment but no case of recurrent central opacity Continuous curvilinear capsulorhexis may increase pearl formation at the capsulotomy edge.2 Caballero et al.3 report a tendency for the epithelial material at the capsulotomy edge to clear spontaneously rather than proliferate. An interesting pattern occurred in the 82-year-old patient presented in Figure 1. In 1988, he had bilateral uneventful phacoemulsification and implantation of 3-piece poly(methyl methacrylate) intraocular lenses. Bilateral Nd:YAG capsulotomies were done in 1991. In December 2001, the patient returned, complaining of visual acuity loss in the right eye. The material illustrated had a typical Elschnig pearl quality (anatomically not true capsule material but occupying the central capsular
J CATARACT REFRACT SURG—VOL 29, FEBRUARY 2003
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CORRESPONDENCE
Figure 1. (Kelly) Left: Central opacity reducing visual acuity to 6/18 10 years after a primary Nd:YAG capsulotomy. Right: Clear visual axis 2 months after a repeat Nd:YAG procedure.
space). A repeat Nd:YAG capsulotomy was done, and visual acuity returned to 6/6. Was this a chance occurrence after 10 years or was there a predisposing factor? The ocular examination was otherwise normal. There was no vitritis, uveitis, glaucoma, or exfoliation. The left eye had epithelial pearls but remained clear centrally. The patient had been treated for myelodysplasia for 6 years on weekly doses of erythropoietin (Procrit威). The total dose of the drug was relatively high. This raises the possibility that the erythropoietin may have increased the cortical proliferation. Erythropoietin is a glycoprotein produced in the kidney that stimulates red blood cell production. It has been manufactured by recombinant DNA techniques and commonly used to treat a variety of conditions associated with anemia. These include renal disease, metastatic cancers, and human-immunodeficiencyvirus-associated conditions.4 Vascular occlusions can occur in the eye if the hematocrit is not carefully monitored. The ocular side effects of erythropoietin are generally rare. There are 3 possible reasons to consider the drug a factor in this case. A relatively high dose of the drug was administered over a long period. There is some evidence that cells other than bone marrow cells respond to erythropoietin.5 Finally, there is evidence that lens epithelial cells (LECs) can react to cytokines similar to erythropoietin.6 Alternatively, the material may have developed in this patient’s pupil randomly.7 There is a small possibil416
ity that the proliferative material was related to the underlying myelodysplasia, but no other systemic leukemia-like changes were noted.8 Complications of erythropoietin are difficult to define since these are usually sick, often terminal, patients with other medications and other systemic conditions. This patient had a history of alcoholism and had also been treated for systemic hypertension. He had short pulse treatments of corticosteroids early in the course of the myelodysplasia. The unusual central recurrent capsular opacity in this patient raises a possible association between longterm erythropoietin treatment and stimulation of LEC proliferation. JAMES S. KELLY, MD Baltimore, Maryland, USA
References 1. Jones NP, Mclead D, Boulton ME. Massive proliferation of lens epithelial remnants after Nd-YAG laser capsulotomy. Br J Ophthalmol 1995; 79:261–263 2. Kato K, Kurosaka D, Bissen-Miyajima H, et al. Elschnig pearl formation along the posterior capsulotomy margin after neodymium:YAG capsulotomy. J Cataract Refract Surg 1997; 23:1556 –1560 3. Caballero A, Garcia-Elskamp C, Losada M, et al. Natural evolution of Elschnig pearl posterior capsule opacification after posterior capsulotomy. J Cataract Refract Surg 2001; 27:1979 –1986 4. Steinberg H, Saravay SM, Wadhwa N, et al. Erythropoietin and visual hallucinations in patients on dialysis. Psychosomatics 1996; 37:556 –563 5. Cerami A, Brines ML, Ghezzi P, Cerami CJ. Effects of
J CATARACT REFRACT SURG—VOL 29, FEBRUARY 2003
CORRESPONDENCE
epoetin alfa on the central nervous system. Semin Oncol 2001; 28(suppl 8):66 –70 6. Nishi O, Nishi K, Fujiwara T, et al. Effects of the cytokines on the proliferation of and collagen synthesis by human cataract lens epithelial cells. Br J Ophthalmol 1996; 80:63–68 7. Bunworasate U, Arnouk H, Minderman H, et al. Eryth-
ropoietin-dependent transformation of myelodysplastic syndrome to acute monoblastic leukemia. Blood 2001; 98:3492–3494 8. Oshika T, Santou S, Kato S, Amano S. Secondary closure of neodymium:YAG laser posterior capsulotomy. J Cataract Refract Surg 2001; 27:1695–1697
J CATARACT REFRACT SURG—VOL 29, FEBRUARY 2003
417
the left eye received ⫹2.00 ⫹2.50 ⫻ 180 instead of the planned correction. Postoperatively, the UCVA in the right eye was emmetropia (1.0); in the left eye, it was 0.2 with a refraction of ⫹2.50 ⫺5.50 ⫻ 180 and the BCVA was 0.8. The corneal pachymetry was 590 m in the right eye and 585 m in the left eye, and the keratometry was 44.00/46.25 D and 42.75/47.75 D, respectively. Three months after the LASIK procedure, reintervention was done using the cross-cylinder technique: ⫺2.50 ⫻ 180 and ⫹3.00 ⫻ 90. Three months later, the UCVA improved to 0.9, the pachymetry was 550 m, and the keratometry reading was 44.00/46.50 D. Case 3 A 36-year-old man was referred to the refractive unit with a BCVA of 1.0 and a refraction of ⫹2.00 ⫺2.00 ⫻ 5 in the right eye and 0.7 and a refraction of ⫹4.50 ⫺5.25 ⫻ 170 in the left eye. The pachymetry was 515 m and 510 m, respectively, and the keratometry, 41.25/43.50 D and 40.00/44.75 D, respectively. Laser in situ keratomileusis was performed to target emmetropia as follows: ⫹2.00 ⫻ 95 in the right eye and ⫺0.75 ⫹5.25 ⫻ 170 instead of ⫺0.75 ⫹5.25 ⫻ 80 in the left eye. One month after LASIK, the UCVA was 0.9 and the BCVA was 1.0 with ⫹0.5 ⫺0.5 ⫻ 90 in the right eye and less than 0.05 and 0.6 with ⫹7.0 ⫺10.0 ⫻ 170 in the left eye. The pachymetry was 514 m and 480 m, respectively. The keratometry was 42.50/ 42.75 D in the right eye and 38.00/49.25 D in the left eye. Astigmatic keratotomy was performed in the left eye in a trial to decrease the iatrogenic astigmatism. Three months after the AK, the UCVA was 0.1 and the BCVA, 0.9 with ⫹3.00 ⫺5.00 ⫻ 180. The keratometry was 39.25/46.00 D and at this point, re-LASIK was performed using the cross-cylinder technique: ⫺2.00 ⫻ 180 and ⫹3.00 ⫻ 90. Two months after the re-LASIK procedure, the UCVA was 1.0 bilaterally. The pachymetry was 514 m in the right eye and 430 m in the left eye. The keratometry was 42.75/43.00 D and 41.00/44.00 D, respectively.
Discussion One major problem in LASIK practice is inaccurate orientation of the ablation profile because of inadequate preoperative evaluation or feeding incorrect data into
the laser. This problem will lead to the development of induced astigmatism, which can be difficult to manage and lead to catastrophic visual impairment. Paying more attention to the process of handling patients’ data could prevent a long nightmare. Our cases developed induced astigmatism due to misreading the astigmatic axis in 1 case and to inputing the wrong axis in the other 2 cases. All the cases could be managed by using AK combined with re-LASIK or LASIK using the cross-cylinder technique. Although the outcomes were satisfactory, the effort and stress could have been prevented by meticulously reviewing each patient’s report before engaging the laser. If this error occurs with the resulting induced astigmatism, a combination of AK and cross-cylinder LASIK ablation can be effective when the corneal pachymetry is sufficient for the procedure. JOSE RODR´IGUEZ-PRATS, MD AHMED GALAL AHMED, MD Ma-JOSE AYALA, MD JORGE L. AL´IO, MD, PhD Alicante, Spain
Recurrent Capsule Opacity and Erythropoietin
T
here are no extensive case series of recurrent capsule opacity in uncomplicated senile cataract. Recurrences involve children, uveitis, or vitreoretinal pathology, not a routine case in patients over 60 years of age.1 In my last 2500 neodymium:YAG (Nd:YAG) laser capsulotomies, there were contractions that required treatment but no case of recurrent central opacity Continuous curvilinear capsulorhexis may increase pearl formation at the capsulotomy edge.2 Caballero et al.3 report a tendency for the epithelial material at the capsulotomy edge to clear spontaneously rather than proliferate. An interesting pattern occurred in the 82-year-old patient presented in Figure 1. In 1988, he had bilateral uneventful phacoemulsification and implantation of 3-piece poly(methyl methacrylate) intraocular lenses. Bilateral Nd:YAG capsulotomies were done in 1991. In December 2001, the patient returned, complaining of visual acuity loss in the right eye. The material illustrated had a typical Elschnig pearl quality (anatomically not true capsule material but occupying the central capsular
J CATARACT REFRACT SURG—VOL 29, FEBRUARY 2003
415
CORRESPONDENCE
Figure 1. (Kelly) Left: Central opacity reducing visual acuity to 6/18 10 years after a primary Nd:YAG capsulotomy. Right: Clear visual axis 2 months after a repeat Nd:YAG procedure.
space). A repeat Nd:YAG capsulotomy was done, and visual acuity returned to 6/6. Was this a chance occurrence after 10 years or was there a predisposing factor? The ocular examination was otherwise normal. There was no vitritis, uveitis, glaucoma, or exfoliation. The left eye had epithelial pearls but remained clear centrally. The patient had been treated for myelodysplasia for 6 years on weekly doses of erythropoietin (Procrit威). The total dose of the drug was relatively high. This raises the possibility that the erythropoietin may have increased the cortical proliferation. Erythropoietin is a glycoprotein produced in the kidney that stimulates red blood cell production. It has been manufactured by recombinant DNA techniques and commonly used to treat a variety of conditions associated with anemia. These include renal disease, metastatic cancers, and human-immunodeficiencyvirus-associated conditions.4 Vascular occlusions can occur in the eye if the hematocrit is not carefully monitored. The ocular side effects of erythropoietin are generally rare. There are 3 possible reasons to consider the drug a factor in this case. A relatively high dose of the drug was administered over a long period. There is some evidence that cells other than bone marrow cells respond to erythropoietin.5 Finally, there is evidence that lens epithelial cells (LECs) can react to cytokines similar to erythropoietin.6 Alternatively, the material may have developed in this patient’s pupil randomly.7 There is a small possibil416
ity that the proliferative material was related to the underlying myelodysplasia, but no other systemic leukemia-like changes were noted.8 Complications of erythropoietin are difficult to define since these are usually sick, often terminal, patients with other medications and other systemic conditions. This patient had a history of alcoholism and had also been treated for systemic hypertension. He had short pulse treatments of corticosteroids early in the course of the myelodysplasia. The unusual central recurrent capsular opacity in this patient raises a possible association between longterm erythropoietin treatment and stimulation of LEC proliferation. JAMES S. KELLY, MD Baltimore, Maryland, USA
References 1. Jones NP, Mclead D, Boulton ME. Massive proliferation of lens epithelial remnants after Nd-YAG laser capsulotomy. Br J Ophthalmol 1995; 79:261–263 2. Kato K, Kurosaka D, Bissen-Miyajima H, et al. Elschnig pearl formation along the posterior capsulotomy margin after neodymium:YAG capsulotomy. J Cataract Refract Surg 1997; 23:1556 –1560 3. Caballero A, Garcia-Elskamp C, Losada M, et al. Natural evolution of Elschnig pearl posterior capsule opacification after posterior capsulotomy. J Cataract Refract Surg 2001; 27:1979 –1986 4. Steinberg H, Saravay SM, Wadhwa N, et al. Erythropoietin and visual hallucinations in patients on dialysis. Psychosomatics 1996; 37:556 –563 5. Cerami A, Brines ML, Ghezzi P, Cerami CJ. Effects of
J CATARACT REFRACT SURG—VOL 29, FEBRUARY 2003
CORRESPONDENCE
epoetin alfa on the central nervous system. Semin Oncol 2001; 28(suppl 8):66 –70 6. Nishi O, Nishi K, Fujiwara T, et al. Effects of the cytokines on the proliferation of and collagen synthesis by human cataract lens epithelial cells. Br J Ophthalmol 1996; 80:63–68 7. Bunworasate U, Arnouk H, Minderman H, et al. Eryth-
ropoietin-dependent transformation of myelodysplastic syndrome to acute monoblastic leukemia. Blood 2001; 98:3492–3494 8. Oshika T, Santou S, Kato S, Amano S. Secondary closure of neodymium:YAG laser posterior capsulotomy. J Cataract Refract Surg 2001; 27:1695–1697
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