Munchausen's syndrome. Clin Experiment Oph ... Ocular pathology of Maroteaux-Lamy syndrome. (systemic ... mechanical corneal trephination with the excimer.
Cornea
Volume 30, Number 12, December 2011
Examination demonstrated bestcorrected visual acuity of 20/200 in the right eye and 20/20 in her left eye. Slitlamp examination demonstrated moderate conjunctival injection and a complete epithelial loss across the cornea. The corneal sensation was normal. The anterior chamber was quiet. The pupil reacted normally, and the remainder of the ocular examination was normal. The clinical appearance was consistent with topical anesthetic abuse caused by the use of benzonatate topically. The cause of the original ocular irritation could not be found. Consideration of an original viral etiology (adenovirus, herpes simplex virus, and herpes zoster ophthalmicus) was considered. The initial treatment was to stop all current ocular medications and start erythromycin ointment 4 times per day and cycloplegia with atropine 1% twice per day. The corneal epithelium healed rapidly over the next 4 days, and the patient had gradual resolution of pain and vision. This case demonstrates the resourcefulness of our patients and their families to relieve the severe pain associated with ocular irritation. The diagnosis and treatment of a corneal abrasion should always include a careful history of possible causative agents, including mechanical trauma, underlying ocular problems, and current medications. Financial disclosures/conflicts of interest: None reported. Andrew J. Hendershot, MD Landon Colling, MD Thomas F. Mauger, MD The Havener Eye Institute The Ohio State University Medical Center Columbus, OH
REFERENCES 1. Moreira LB, Kasetsuwan N, Sanchez D, et al. Toxicity of topical anesthetic agents to human keratocytes in vivo. J Cataract Refract Surg. 1999;25:975–980. 2. Varga JH, Rubinfeld RS, Wolf TC, et al. Topical anesthetic abuse ring keratitis: report of four cases. Cornea. 1997;16:424–429. 3. Ansari H, Garibaldi D, Jun AS. Anaesthetic abuse keratopathy as a manifestation of ocular Munchausen’s syndrome. Clin Experiment Ophthalmol. 2006;34:81–92. 4. Homsi J, Walsh D, Nelson KA. Important drugs for cough in advanced cancer. Support Care Cancer. 2001;9:565–574.
q 2011 Lippincott Williams & Wilkins
Deep Anterior Lamellar Keratoplasty for Corneal Opacification in Maroteaux–Lamy Syndrome: Is It the Treatment of Choice? To the Editors: Recently, Rahmati-Kamel et al1 reported an interesting case of Maroteaux– Lamy syndrome (MLS). The patient underwent deep anterior lamellar keratoplasty (DALK) for visual rehabilitation. Best-corrected visual acuity improved to 20/25, and corneal graft was clear 24 months after surgery. The authors emphasize the low complication rate of DALK compared with penetrating keratoplasty (PK), and based on the excellent postoperative course of their case, they suggest that DALK may represent the treatment of choice for corneal opacification in such patients. Nevertheless, we would like to underscore the importance of some aspects regarding the corneal opacification occurring in MLS, which, in our opinion, are subject to extensive discussion. MLS is a lysosomal storage disease, characterized by cytoplasmic accumulation of glycosaminoglycans (GAGs), especially keratan sulfate, causing cell enlargement, degeneration, and finally cell death. Corneal opacification in MLS occurs primarily as a result of the degeneration of keratocytes, followed by abnormal formation of GAGs in corneal stroma, disorganization of collagen fibrils, and disruption of the parallel arrangement of collagen lamellae.2 However, there is strong evidence that in MLS, not only the corneal epithelium and stroma but also the endothelium is severely affected. Kenyon et al3 were the first to document in 2 cases of MLS that Descemet membrane was abnormal with vacuolated endothelium. Later on, Akhtar et al4 provided evidence that in 1 case of MLS, endothelium displayed marked degeneration. The accumulation of GAGs in the posterior stroma, and especially in the pre-Descemet stroma, was more prominent compared with the anterior stroma. Moreover, the endothelium in MLS cornea demonstrated a positive
Letters to the Editor
immunohistochemical signal for keratan sulfate, which was not the case in normal cornea. In view of these findings, we believe that DALK may not always be sufficient for the treatment of patients with MLS, especially when corneal opacification does not allow an adequate preoperative evaluation of the endothelial cell status. In our opinion, excimer laser-assisted PK seems to be more reasonable in such patients because this technique provides multiple advantages in cases of avascular corneal pathologies requiring PK.5 Of course, a comparative study of the long-term postoperative follow-up of patients with MLS after DALK or PK would provide valuable insights in our attempt to assess the efficacy and safety of these 2 methods for the treatment of corneal clouding in MLS. However, MLS is rare and diverse, which may impede the efforts to address this question in a proper and adequate manner. Financial disclosure/conflicts of interest: None reported. Zisis Gatzioufas, MD Berthold Seitz, MD Department of Ophthalmology University of Saarland Homburg/Saar, Germany
REFERENCES 1. Rahmati-Kamel M, Javadi M, Shojaei A, et al. Deep anterior lamellar keratoplasty for Maroteaux-Lamy syndrome. Cornea. 2010;29:1459–1461. 2. Ashworth JL, Biswas S, Wraith E, et al. Mucopolysaccharidoses and the eye. Surv Ophthalmol. 2006;51:1–17. 3. Kenyon KR, Topping TM, Green RW, et al. Ocular pathology of Maroteaux-Lamy syndrome (systemic mucopolysaccharidosis type VI): histopathologic and ultrastructural report of two cases. Am J Ophthalmol. 1972;73:718–741. 4. Akhtar S, Tullo A, Caterson B, et al. Clinical and morphological features including expression of betaig-h3 and keratan sulphate proteoglycans in Maroteaux-Lamy syndrome type B and in normal cornea. Br J Ophthalmol. 2002;86: 147–151. 5. Seitz B, Langenbucher A, Kus MM, et al. Nonmechanical corneal trephination with the excimer laser improves outcome after penetrating keratoplasty. Ophthalmology. 1999;106:1156–1164.
Reply: The mucopolysaccharidoses (MPSs) are a group of disorders caused by inherited defects in lysosomal enzymes resulting in widespread intra- and extracellular accumulation of glycosaminoglycans. They are subdivided according to enzyme defect and systemic manifestations www.corneajrnl.com |
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