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Retained Nuclei After Cataract Surgery
Letters to the Editor
Retained Nuclei After Cataract Surgery Dear Editor: We congratulate Blodi et al on their article entitled, "Retained Nuclei after Cataract Surgery" (Ophthalmology 1992;99:41-4). We certainly agree with their findings. However, loss of the nucleus into the vitreous cavity is not necessarily a catastrophe. This complication can be handled intraoperatively by anterior segment surgeons. We have managed these cases by immediately suturing a double Flieringa to the globe and extending the limbal incision to 180° to 270°. The cornea can then be retracted and an open-sky vitrectomy performed. With the use of irrigation and scleral depression, nuclear fragments are visualized and can be removed with a lens loop, cryoprobe, or fine-tooth forceps. If the nucleus removal is atraumatic, an intraocular lens can still be implanted. With this approach, anterior segment surgeons should be able to manage this particular complication and avoid many of its devastating sequelae. RICHARD A. EIFERMAN, MD LEON LANE, MD MARKLAW,MD YVONNE FIELDS, COT
Louisville, Kentucky
Authors'reply Dear Editor: We agree with the authors that the complication of nuclear loss into the vitreous cavity can be handled intraoperatively by anterior segment surgeons in selected cases. We agree that an open-sky vitrectomy can be performed with retneval of many nuclear fragments. However, we disagree with the approach of creating a 270° limbal incision with the use of irrigation and scleral depression in an attempt to retrieve lost nuclei. The use of a cryoprobe may cause vitreous traction and subsequent retinal detachment. We believe it is preferable to remove such posteriorly dislocated nuclei with the control of a pars plana vitrectomy approach. The posterior capsule often can be preserved, and a posterior chamber intraocular lens can be inserted at the time of the vitrectomy if it was not inserted during the first procedure. BARBARA A. BLODI, MD HARRY W. FLYNN, Jr. MD Miami, Florida Dear Editor: The article by Blodi et al entitled "Retained Nuclei after Cataract Surgery" calls attention to the problems of managing lens material lost in the vitreous at the time of cataract surgery. Since the authors do not describe the distribution function they used for calculating confidence intervals us-
ing the chi-square distribution (with Yates continuity correction, which is appropriate for their data), there is no significant difference at the 95% confidence interval between early and late vitrectomy for any of the clinical features they observed. The authors' data suggest there may be increased retinal complications with early vitrectomy and increased glaucoma with late vitrectomy in their cases. The patients in this series were a select group of severely complicated cases referred for tertiary care. These patients provide no basis for making general recommendations for managing posteriorly dislocated lens material, as the authors point out in their last paragraph. Unfortunately, vitrectomy complications are sometimes attributed to delayed referral. Such suggestions are resulting in increasing litigation. There are no established standards of care for managing posteriorly dislocated lens fragments. The authors report that many cases do well without surgical intervention. In the absence of controlled studies to provide management guidelines, inflexible rules based on anecdotal observations cannot substitute for responsible clinical judgment. This article is a valuable contribution for raising important questions and generating hypotheses about the management of retained nuclear material and will hopefully stimulate more work on this important problem. A multicentered study sponsored by the National Eye Institute might be useful in providing the information necessary to reliably establish standards of care in the treatment of posteriorly dislocated lens fragments. GEORGE E. MARAK Jr., MD Alexandria, Virginia
Authors'reply Dear Editor: We thank Dr. Marak for his interest in our article. With regard to his first point, the difference between the proportions of cases with chronic glaucoma in those patients treated early and late (>3 weeks) is statistically significant (P = 0.0369, Fisher's two-tailed exact test). Fisher's exact test was used because the small sample size in this study produced expected values less than 5, compromising the normal theory approximations on which the chi-squared test with Yate's correction is based. It cannot be stated from our data that retinal complications were increased by early vitrectomy. We disagree with Dr. Marak regarding the management of these cases. All patients in this series were referred by anterior segment surgeons because of their clinical impression that the patient's eye was not tolerating the retained lens nucleus despite continuous topical corticosteroid therapy. Because of the visual loss, intraocular inflammation, secondary glaucoma, and coexisting retinal detachment, these patients were referred for management
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Retained Nuclei After Cataract Surgery Dear Editor: We congratulate Blodi et al on their article entitled, "Retained Nuclei after Cataract Surgery" (Ophthalmology 1992;99:41-4). We certainly agree with their findings. However, loss of the nucleus into the vitreous cavity is not necessarily a catastrophe. This complication can be handled intraoperatively by anterior segment surgeons. We have managed these cases by immediately suturing a double Flieringa to the globe and extending the limbal incision to 180° to 270°. The cornea can then be retracted and an open-sky vitrectomy performed. With the use of irrigation and scleral depression, nuclear fragments are visualized and can be removed with a lens loop, cryoprobe, or fine-tooth forceps. If the nucleus removal is atraumatic, an intraocular lens can still be implanted. With this approach, anterior segment surgeons should be able to manage this particular complication and avoid many of its devastating sequelae. RICHARD A. EIFERMAN, MD LEON LANE, MD MARKLAW,MD YVONNE FIELDS, COT
Louisville, Kentucky
Authors'reply Dear Editor: We agree with the authors that the complication of nuclear loss into the vitreous cavity can be handled intraoperatively by anterior segment surgeons in selected cases. We agree that an open-sky vitrectomy can be performed with retneval of many nuclear fragments. However, we disagree with the approach of creating a 270° limbal incision with the use of irrigation and scleral depression in an attempt to retrieve lost nuclei. The use of a cryoprobe may cause vitreous traction and subsequent retinal detachment. We believe it is preferable to remove such posteriorly dislocated nuclei with the control of a pars plana vitrectomy approach. The posterior capsule often can be preserved, and a posterior chamber intraocular lens can be inserted at the time of the vitrectomy if it was not inserted during the first procedure. BARBARA A. BLODI, MD HARRY W. FLYNN, Jr. MD Miami, Florida Dear Editor: The article by Blodi et al entitled "Retained Nuclei after Cataract Surgery" calls attention to the problems of managing lens material lost in the vitreous at the time of cataract surgery. Since the authors do not describe the distribution function they used for calculating confidence intervals us-
ing the chi-square distribution (with Yates continuity correction, which is appropriate for their data), there is no significant difference at the 95% confidence interval between early and late vitrectomy for any of the clinical features they observed. The authors' data suggest there may be increased retinal complications with early vitrectomy and increased glaucoma with late vitrectomy in their cases. The patients in this series were a select group of severely complicated cases referred for tertiary care. These patients provide no basis for making general recommendations for managing posteriorly dislocated lens material, as the authors point out in their last paragraph. Unfortunately, vitrectomy complications are sometimes attributed to delayed referral. Such suggestions are resulting in increasing litigation. There are no established standards of care for managing posteriorly dislocated lens fragments. The authors report that many cases do well without surgical intervention. In the absence of controlled studies to provide management guidelines, inflexible rules based on anecdotal observations cannot substitute for responsible clinical judgment. This article is a valuable contribution for raising important questions and generating hypotheses about the management of retained nuclear material and will hopefully stimulate more work on this important problem. A multicentered study sponsored by the National Eye Institute might be useful in providing the information necessary to reliably establish standards of care in the treatment of posteriorly dislocated lens fragments. GEORGE E. MARAK Jr., MD Alexandria, Virginia
Authors'reply Dear Editor: We thank Dr. Marak for his interest in our article. With regard to his first point, the difference between the proportions of cases with chronic glaucoma in those patients treated early and late (>3 weeks) is statistically significant (P = 0.0369, Fisher's two-tailed exact test). Fisher's exact test was used because the small sample size in this study produced expected values less than 5, compromising the normal theory approximations on which the chi-squared test with Yate's correction is based. It cannot be stated from our data that retinal complications were increased by early vitrectomy. We disagree with Dr. Marak regarding the management of these cases. All patients in this series were referred by anterior segment surgeons because of their clinical impression that the patient's eye was not tolerating the retained lens nucleus despite continuous topical corticosteroid therapy. Because of the visual loss, intraocular inflammation, secondary glaucoma, and coexisting retinal detachment, these patients were referred for management
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