Posterior Chamber vs Anterior Chamber Intraocular Lenses After Vitreous Presentation in the Presence of Adequate Capsular Support

REFERENCES

REPLY

1. Buratto L, Bohm E. The use of the femtosecond laser in penetrating keratoplasty. Am J Ophthalmol 2007;143:737– 742. 2. Busin M, Arffa RC. Microkeratome-assisted mushroom keratoplasty with minimal endothelial replacement. Am J Ophthalmol 2005;140:138 –140.

WE WOULD LIKE TO THANK DRS GOLDSTEIN AND TESSLER

for their interest in our article.1 We agree that the maculopathy observed in patients treated with blood– brain barrier disruption (BBBD) was more likely to be secondary to mannitol-induced disruption of the outer blood–retinal barrier and less likely to be caused by methotrexate toxicity. Evaluation of patients undergoing BBBD with agents other than methotrexate and those receiving intraarterial methotrexate without BBBD may help to elucidate the pathogenesis of the maculopathy.

Editor’s Note: Dr Buratto failed to reply to this correspondence despite repeated requests by the Journal.

ANAT GALOR

Miami, Florida

Maculopathy as a Complication of Blood–Brain Barrier Disruption in Patients with Central Nervous System Lymphoma

ARUN D. SINGH

Cleveland, Ohio

REFERENCE

1. Galor A, Ferece SJ, Singh AD, et al. Maculopathy as a complication of blood– brain barrier disruption in patients with central nervous system lymphoma. Am J Ophthalmol 2007;144:45– 49.

EDITOR: WE ENJOYED THE ARTICLE BY GALOR AND ASSOCIATES ON

the maculopathy associated with blood– brain barrier disruption.1 We also have observed a maculopathy in patients treated with blood– brain barrier disruption for central nervous system lymphoma. The authors discuss the possibility that it is methotrexate that results in toxicity, although they did not suggest this as a strong possibility. We agree that this is not very likely, because patients receiving intraocular methotrexate in the absence of blood– brain disruption are not known to experience maculopathy. As well, intravitreally administered methotrexate has not been shown histologically to result in pigmentary changes in the macula, and in fact, the retinal structures in rabbits receiving intraocular methotrexate are normal.2 We look forward to the results of prospective trials underway by the authors designed to help elucidate the cause of these potential visually significant retinal pigment epithelium changes.

Posterior Chamber vs Anterior Chamber Intraocular Lenses After Vitreous Presentation in the Presence of Adequate Capsular Support EDITOR: I COMMEND DRS GASTER AND COLLINS AND THE VA COOP-

erative Cataract Study Group for their prospective randomized study to elucidate the long-term outcomes of posterior chamber (PC) intraocular lens (IOL) vs anterior chamber (AC) IOL implantation in the presence of adequate capsular support after vitreous presentation during extracapsular cataract surgery,1 but I take issue with the conclusion reached by Drs Belani and Masket in their accompanying editorial.2 Drs Belani and Masket state that “based on this investigation, surgeons should feel free to use either lens type in the presence of vitreous loss when adequate capsular support is present.” A previous publication of the VA Cooperative Cataract Study Group’s one-year results showed a highly significant difference in patients achieving 20/40 acuity or better when randomized to PC IOL (91%) vs AC IOL implantation (79%) in the presence of adequate capsular support (P ⫽ .003).3 Although the difference was not sustained at two, three, and four years of follow-up,1 the high dropout rate of study participants (about 30% at two years, 35% at three years, and 45% at four years compared to less than 10% at one year) makes the long-term results suspect. The lack of standardization across centers for determining when posterior capsule opacification warranted YAG laser

DEBRA A. GOLDSTEIN HOWARD H. TESSLER

Chicago, Illinois

REFERENCES

1. Galor A, Ference SJ, Singh AD, et al. Maculopathy as a complication of blood– brain barrier disruption in patients with central nervous system lymphoma. Am J Ophthalmol 2007;144:45– 49. 2. Deng SX, Penland S, Gupta S, et al. Methotrexate reduces the complications of endophthalmitis resulting from intravitreal injection compared to dexamethasone in a rabbit model. Invest Ophthalmol Vis Sci 2006;47:1516 –1521.

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capsulotomy could also have affected the long-term visual acuity results. Drs Belani and Masket allude to patients’ increasing expectations after surgery and suggest that other measures including uncorrected visual acuity, glare disability, contrast sensitivity, and pain should be considered as outcome measures in future investigations.2 Postoperative recovery time (i.e., time to achieve best postoperative visual acuity) is also important to patients, and I venture most would find waiting over a year with AC IOL implantation to achieve a comparable result to a PC IOL unacceptable. Therefore, the publications from the VA Cooperative Cataract Study Group seem to support implantation of a PC IOL in preference to an open-loop AC IOL in the presence of adequate capsular support after vitreous presentation during cataract surgery.

endothelial cell loss, late IOL dislocation, and additional intraoperative complications associated with either approach, merit consideration. We feel that this important study by Gaster and Collins has produced valuable information for cataract surgeons to consider, but does not provide convincing evidence for us to determine that ACIOL use is categorically inferior to PCIOL use in the setting of vitreous loss with adequate capsular support. Therefore, it remains reasonable for the surgeon to utilize either option based upon his or her clinical judgement and preference. SHALEEN L. BELANI SAMUEL MASKET

Los Angeles, California

PRESTON H. BLOMQUIST

Dallas, Texas

1. Gaster RN, Collins JF. The long-term effect of vitreous presentation during extracapsular cataract surgery on postoperative visual acuity. Am J Ophthalmol 2007;144:186 –194.

REFERENCES

1. Gaster RN, Collins JF. The long-term effect of vitreous presentation during extracapsular cataract surgery on postoperative visual acuity. Am J Ophthalmol 2007;144:186 –194. 2. Belani SL, Masket S. The long-term effect of vitreous presentation during extracapsular cataract surgery on postoperative visual acuity [editorial]. Am J Ophthalmol 2007;144:286 –287. 3. Collins JF, Gaster RN, Krol WF, Colling CL, Kirk GF, Smith TJ. A comparison of anterior chamber and posterior chamber intraocular lenses after vitreous presentation during cataract surgery: the Department of Veterans Affairs Cooperative Cataract Study. Am J Ophthalmol 2003;136:1–9.

REPLY WE AGREE WITH DR BLOMQUIST THAT THIS EXTREMELY

important study by Gaster and Collins1 deserves commendation as it is the first prospective long-term comparative study in the literature to evaluate unsutured posterior chamber intraocular lens (PCIOLs) and open-loop anterior chamber intraocular lens (ACIOLs) in the presence of vitreous loss and sufficient capsular support. However, we do not believe that the study results indicate that one intraocular lens (IOL) is clearly superior to the other with respect to the main outcome measure of best-corrected visual acuity (BCVA) of 20/40 or better. While a statisticially significant difference between the PCIOL and ACIOL groups was initially found at one-year of follow-up, this difference was not sustained at later time periods. Though certainly possible, there is no reason to believe that the increase in study dropout rates at two, three, and four years would bias one group over another. As mentioned previously, the outcome measure of BCVA of 20/40 or better may not be sufficient alone; other factors such as pain, glare disability, and contrast sensitivity may need to be investigated. In addition, other complications including VOL. 144, NO. 6

REFERENCE

Ectatic Disorders Associated with a Claw-shaped Pattern on Corneal Topography EDITOR: LEE AND ASSOCIATES NICELY DEMONSTRATE THAT CLAW-

shaped topographic patterns can be found in eyes with clinical features typical of either keratoconus or pellucid marginal corneal degeneration and therefore are not diagnostic for either specific ectatic disease classification.1 However, I believe their use of the terms “keratoconus suspect” and “pellucid suspect” is counter to commonly accepted usage today and is therefore a potential source of confusion. This clarification and the screening value of claw-shaped topographic patterns deserve further discussion. There has been great variability in the terminology used to describe varying clinical manifestations of ectatic corneal diseases.2 However, in common usage today, the terms “keratoconus suspect” and “pellucid suspect” imply eyes that have only topographic features of these ectatic processes in the absence of clinical findings. In their article, Lee and associates separated eyes into definite or suspect keratoconus or pellucid marginal categories; however, eyes in both categories had clinical findings, albeit at different levels of severity. Therefore, it seems more logical to classify all of the eyes in this study as having keratoconus or pellucid marginal corneal degeneration and to reserve use of the term suspect to describe eyes with abnormal topographic patterns but without clinical abnormalities. Further, the authors correctly point out the potential usefulness in differentiating these two ectatic processes

CORRESPONDENCE

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