Primary Megalocornea: Clinical Features for Differentiation From Infantile Glaucoma

Transcription

1 Primary Megalocornea: Clinical Features for Differentiation From Infantile Glaucoma Ching Lin Ho, FRCSEd; and David S. Walton, MD ABSTRACT Purpose: To describe the ocular findings in megalocornea to assist in its differentiation from infantile glaucoma in the evaluation of children with abnormally enlarged corneas. Methods: The clinical findings of 4 boys found to have megalocornea following referral for evaluation of large corneas and suspected glaucoma were reviewed. The authors are from the Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, Massachusetts. Dr. Ho is also from the Singapore National Eye Centre, Singapore, Republic of Singapore. Originally submitted June 25, Accepted for publication September 19, Address reprint requests to David S. Walton, MD, 2 Longfellow Place, Suite 201, Boston, MA Presented in part at the 73rd Meeting of the Association of Vision Research in Ophthalmology; May 4-9, 2003; Ft. Lauderdale, Florida. The authors have no industry relationships to disclose. In accordance with ACCME policies, the audience is advised that this continuing medical education activity may contain references to unlabeled uses of FDA-approved products or to products not approved by the FDA for use in the United States. The faculty members have been made aware of their obligation to disclose such usage. The material presented at or in any SLACK Incorporated continuing medical education activities does not necessarily reflect the views and opinions of SLACK Incorporated. Neither SLACK Incorporated nor the faculty endorse or recommend any techniques, commercial products, or manufacturers. The faculty/authors may discuss the use of materials and/or products that have not yet been approved by the U.S. Food and Drug Administration. All readers and continuing education participants should verify all information before treating patients or utilizing any product. EDUCATIONAL OBJECTIVES 1. To identify the defining diagnostic signs of primary megalocornea. 2. To compare primary megalocornea, infantile glaucoma, and keratoglobus to enable their differentiation in the evaluation of children with enlarged corneas. 3. To summarize the literature related to primary megalocornea and to become more familiar with the associated ocular signs and potential associated diseases. See quiz on page 46; no payment required. Results: Three of the 4 patients had photophobia. Clear and enlarged corneas were observed associated with deep anterior chambers, posterior bowing of the irides, and normal intraocular pressures (IOPs) in all eyes. Transillumination of the irides was found in 6 of 8 eyes and pigment dispersion was seen in 4 of 8 eyes. Pigment dispersion appeared to be acquired over time, and the youngest patient in this series who had pigment dispersion detected on slit-lamp examination was 15 years; the youngest patient with the condition detected on gonioscopy was 8 years. No breaks in Descemet s membrane were present. Family history obtained from 3 of the 4 patients revealed evidence of sex-linked recessive inheritance. These findings are distinct from the clinical features of infantile glaucoma characterized by elevated IOP, breaks in Descemet s membrane, JOURNAL OF PEDIATRIC OPHTHALMOLOGY & STRABISMUS 11

2 corneal edema, a generally flat iris profile, less pronounced enlargement of the anterior segment, the absence of iris transillumination and pigment dispersion, and autosomal recessive inheritance. Three patients had corneal size asymmetry, a finding that has not been previously reported. Conclusion: Hereditary megalocornea has defining clinical findings that help to identify and differentiate it from other causes of enlarged corneas. Asymmetry in corneal size does not preclude its diagnosis. J Pediatr Ophthalmol Strabismus 2004;41: INTRODUCTION When a child is evaluated for abnormally large corneas, the determination of their clinical significance is necessary. The presence or absence of glaucoma is an especially important consideration. Primary congenital large corneas (megalocornea) must also be considered. Megalocornea is associated with other ocular malformations of the anterior segment including the iris and lens. 1 Although the ocular anomalies usually exist alone, their association with systemic conditions such as Marfan s syndrome, Down s syndrome, Soto s syndrome, and other mental and growth retardation syndromes has been described. 1-4 Megalocornea and glaucoma must each be differentiated from keratoglobus, a rare inherited corneal condition with ectasia and congenital anterior bulging of the cornea. Megalocornea is an unusual hereditary congenital developmental anomaly of the anterior segment. 1 At birth, the corneas in this condition are typically greater than 12 mm in diameter, and by 1 year of age, they are greater than 13 mm in diameter. The corneas are always clear, and the anterior chambers are strikingly deep. The angle may possess abnormal processes and increased trabecular pigmentation, and cataracts occur in most adult patients. 5 Mosaic corneal dystrophy has been reported in adults. 6 Although megalocornea associated with deep anterior chamber, enlargement of the lens iris diaphragm and ciliary ring, iris transillumination, myopia, and lens subluxation or dislocation has been labeled as anterior megalophthalmos, 1,7-9 this probably represents a more severe manifestation of this condition rather than a separate disease entity. Megalocornea is seen most frequently in males and is inherited by an X-linked recessive gene linked to the Xq12-q26 region. 10 Less common autosomal dominant and recessive modes of inheritance have also been described. 4,11-13 We describe the clinical findings of 4 boys referred for evaluation of suspected glaucoma and found to possess primary megalocornea associated with helpful defining ocular abnormalities. The goal of this study is to provide clinical information to assist with the identification of primary megalocornea and its differentiation from glaucoma, especially in young patients when the examination for glaucoma, including tonometry, can be uncertain or inconclusive in the office setting. METHODS Four boys were referred for suspected glaucoma and were found to possess primary megalocornea. When first seen, 3 of the boys were younger than 8 months and the fourth was 8 years. Complete ophthalmologic examinations included assessments of vision; corneal size, thickness, and clarity; anterior chamber depth; iris characteristics; keratometry; funduscopy; refraction; ultrasonography; tonometry; and family genetic history. RESULTS (TABLE 1) Each of the 4 boys had a presenting history of enlarged corneas since birth. Three of them had significant photophobia, but none had symptoms of epiphoria or blepharospasm or a history of corneal opacification, which are common in infantile glaucoma. Family history revealed no occurrence of glaucoma but provided evidence consistent with the sex-linked recessive inheritance of megalocornea in 3 of the 4 patients families, with megalocornea in males transmitted by females without megalocornea through two or more generations. The remaining patient had no family history of megalocornea. On examination, excellent visual responses unassociated with nystagmus or an eye deviation were present in all patients. No significant refractive error was found in any of the eyes, with refraction ranging between and D spherical 12 JANUARY/FEBRUARY 2004/VOL 41 NO 1

3 TABLE 1 SUMMARY OF CLINICAL OBSERVATIONS IN THE FOUR BOYS WITH MEGALOCORNEA Characteristic Patient 1 Patient 2 Patient 3 Patient 4 Initial age 1 mo 8 y 7 mo 3 mo Age at last 17 y 8 y 8 y 27 mo examination Reason for initial Glaucoma Glaucoma Glaucoma Glaucoma evaluation Family history of megalocornea Corneal enlargement of 14 mm or larger Normal axial length Very deep anterior chamber Posterior iris bowing Corneal size asymmetry Iris transillumination Pigment on trabecular meshwork Pigment on iris or cornea Iridodonesis Cataracts Enlarged globes Elevated IOP Optic disc abnormalities Impaired vision > 2-D refractive error Systemic abnormality - - Diabetes - mellitus onset at 3 y + = present; - = absent; IOP = intraocular pressure. equivalents. The ocular adnexa and eye movements were normal. Assessment of the anterior segments found all corneas to be clear and abnormally enlarged, with estimated diameters of 14 to 15 mm in all patients, without opacification, scarring, or breaks in Descemet s membrane. Comparative assessment of the corneal diameter in each patient found corneal asymmetry in 3 of the 4 children, with an easily appreciated increment of approximately 0.3 to 1.0 mm in each affected patient (Fig. 1). Slit-lamp assessment suggested that the corneas of all patients were approximately 20% thinner than normal. Pachymetry performed on the oldest patient, who was 17 years, found a central corneal thickness of 475 µm on the right and 463 µm on the left. The anterior chambers of each patient were clear and appropriately characterized as very deep. No flare or particulate matter in the aqueous was seen on slit-lamp examination. Inspection of the irides found the pupils to be round, centrally positioned, and normally reactive to light in all eyes. The iris stroma was blue in 3 of the children and brown in 1. Pronounced posterior bowing of the irides (Fig. 2) was present in all of the 8 eyes. No evidence of iris hypoplasia or atrophy was present. The observed anterior concavity in iris contour was associated with easily observed mid to peripheral iris circumferential transillumination (Fig. 3) in 6 of the 8 eyes. The earliest age at which transillumination was observed was 1 month. Transillumination has remained absent in the eyes of the next youngest patient, who was 27 months at the last examination. Pigment dispersion on the iris JOURNAL OF PEDIATRIC OPHTHALMOLOGY & STRABISMUS 13

4 Figure 1. Corneal size asymmetry in megalocornea. Figure 2. Deep anterior chamber with posterior bowing of the iris. Figure 3. Typical pattern of iris transillumination in megalocornea. Figure 4. Pigment dispersion on the iris and lens surfaces in a 17-year-old boy with megalocornea. Figure 5. Heavy pigmentation in the angle of a 17-year-old boy with megalocornea. and lens surfaces (Fig. 4) was seen in 1 patient from 15 years of age associated with Krukenberg s spindles. The 3 other patients, who were last examined at the ages of 27 months, 8 years, and 8 years, respectively, had no evidence of anterior chamber pigment dispersion on slit-lamp examination, although iris transillumination was present in the latter 2 patients. Koeppe gonioscopy was performed in the assessment of all 4 patients. All angles were found to be wide open, except for the forward position of iris stroma-like tissue against the ciliary body band and posterior trabecular meshwork for 3 circumferential hours inferiorly in both eyes of 1 patient. In that patient, evidence of pigment deposition was absent at 1 month of age in the presence of iris transillumination, but at 15 years he was found to have heavy deposition of pigment on the ciliary body band and trabecular meshwork over the inferior two-thirds of the angle circumference (Fig. 5). Another patient, who had first undergone gonioscopy at 8 years of age, was also found to have heavy deposition of pigment on the trabecular meshwork. The third patient was examined from 7 months to 8 years of age and was found to have no pigment in the angle of either eye despite the presence of bilateral iris transillumination. Gonioscopy performed on the fourth patient, who had no iris transillumination at 27 months of age, found no evidence of pigment deposition on the angle structures. Repetitive eye pressure measurements in each 14 JANUARY/FEBRUARY 2004/VOL 41 NO 1

5 TABLE 2 DIFFERENTIAL DIAGNOSES OF ENLARGED CORNEAS IN CHILDHOOD Characteristic Glaucoma Megalocornea Keratoglobus Onset Congenital or infantile Congenital Congenital Corneal history Progressive corneal Stable, clear Bulging with enlargement corneas at birth risk for corneal rupture Inheritance Recessive Sex-linked recessive Recessive Autosomal recessive Autosomal dominant Bilaterality Typical asymmetric Possible asymmetric Bilateral enlargement size Corneal clarity Diffuse or Clear or mosaic Clear or with localized dystrophy scarring cloudiness Corneal thickness Variable Moderately thin Very thin Corneal diameter Progressive enlarge- Large and stable Normal to slight ment enlargement Corneal size Frequent Frequent Atypical asymmetry Anterior chamber Deep Very deep Very deep or flat Iris transillumination Absent Present Absent Posterior iris Minimal Frequent, Absent bowing pronounced Pigment dispersion Absent Frequent in Absent older children K readings Flat Normal Steep Refraction Variable myopia Normal High myopia Gonioscopy Abnormal Minor defects Iris processes Systemic Sturge Weber, Marfan s, Soto s, Joint hyperassociations other pediatric Rieger s, Down s, extensibility, syndromes Neuhauser retardation hearing loss, dental syndromes abnormalities child revealed normal intraocular pressures. No evidence of increasing eye pressures was found. The patient who had the longest follow-up (ie, from 1 month to 17 years of age) and who acquired heavy pigmentation of the angle during this interval maintained a stable pressure between 10 and 15 mm Hg in both eyes. Funduscopy revealed no abnormality in all of the eyes. One of 4 patients showed blurring of the disc margins in both eyes consistent with pseudopapilledema. No evidence of glaucomatous optic neuropathy was found in any of the patients throughout their follow-up periods. Systemic examination and a review of the development history of each child found no pertinent abnormality. One patient experienced the onset of juvenile diabetes mellitus at 3 years of age, and had a positive family history of that disorder. Contact ultrasonography found symmetric and normal axial lengths in both eyes of each patient. Detailed A scan of the eldest patient at 17 years of age showed anterior chamber depths of 6.08 and 6.03 mm, lens thicknesses of 4.05 and 3.89 mm, and axial lengths of and mm for the right and left eye, respectively. Ultrasound biomicroscopy studies on the same patient revealed deep anterior chambers with posterior bowing of the iris, but it was difficult to demonstrate iridozonular contact. DISCUSSION When a child is first recognized to have abnormally large corneas, the possibility of glaucoma should be entertained. The differential diagnosis of large corneas in childhood should include glaucoma, primary megalocornea, and keratoglobus. Familiarity with the defining characteristics of each entity can be helpful (Table 2). JOURNAL OF PEDIATRIC OPHTHALMOLOGY & STRABISMUS 15

6 The most common cause of abnormally large corneas in childhood is glaucoma. Young patients with glaucoma typically demonstrate progressive and asymmetric enlargement of the corneas caused by the elevated intraocular pressure, which is responsible for the secondary signs and symptoms of glaucoma including photophobia, tearing, eye pain, corneal opacification, and tears in Descemet s membrane. These abnormalities are collectively seen especially in affected children with glaucoma who are younger than 2 years. Children with laterecognized infantile glaucoma are first seen for care between 18 months and 6 years of age, and typically have enlarged clear corneas resembling those seen in patients with megalocornea. These patients characteristically have breaks in Descemet s membrane and elevated intraocular pressures. In addition to corneal enlargement, significant photophobia can occur in patients with megalocornea, further confusing its differentiation from infantile glaucoma. This is most likely due to the increased iris translucency resulting in increased intraocular light scatter. 1,14 Asymmetric corneal enlargement may also be found in patients with either glaucoma or megalocornea and is therefore not a helpful differentiating feature (Table 2). To the best of our knowledge, this has not been described, and previous reports and major textbooks have emphasized the bilateral symmetry in corneal diameters in megalocornea as a distinguishing feature from infantile glaucoma. 1,5,7,8 The invaluable diagnostic role of tonometry cannot be overemphasized, but is not always reliable in the initial assessment of the young, fractious child. The anterior segment features of children with primary megalocornea are characteristic and helpful in recognizing this condition and differentiating it from abnormalities secondary to glaucoma (Tables 1 and 2). In primary megalocornea, the anterior segment is strikingly enlarged from birth at the expense of the posterior segment. 15 A-scan findings in a typical patient in this study showed relatively short vitreous lengths of approximately 15 mm in the presence of anterior chamber depths in excess of 6 mm, which were twice that of normal. This is in contrast to the reported mean vitreous length of 18.9 mm and anterior chamber depth of 4.0 mm in infantile glaucoma, 15 where the axial length is increased mostly due to an expansion of the posterior segment. The corneas are large and clear without the Descemet s breaks or opacities commonly seen in infantile glaucoma. In addition, in primary megalocornea, posterior bowing of the irides is present in frequent association with mid to peripheral iris transillumination as well as evidence of anterior chamber pigment dispersion on slit-lamp examination or gonioscopy in later childhood. These features of the iris are absent in primary infantile glaucoma. The mechanism of pigment dispersion has been discussed, and the similarity appropriately compared with that of older patients with pigmentary glaucoma. 16 Iridozonular contact and rubbing appears to be a plausible mechanism in view of the posterior bowing of the iris, the iris transillumination, and the observation of pigment in the angle in the older children in this series, as well as reported ultrasound biomicroscopy studies demonstrating this contact. Ectopia lentis is rare with megalocornea, but iridodonesis is another sign that may be seen in patients with primary megalocornea (Table 1). 17 When glaucoma occurs with primary megalocornea, it is almost always secondary to lens subluxation. 1 Although coexistence of megalocornea and congenital glaucoma in families has been reported, the patients with megalocornea did not have glaucoma. 11,18,19 One case of unilateral primary glaucoma in a 50-year-old African American patient with bilateral megalocornea and Soto s syndrome has been described in the literature. 20 It is possible that this patient has primary open angle glaucoma in addition to megalocornea. To the best of our knowledge, there has been no other report of definite glaucoma in primary hereditary megalocornea. Ocular hypertension unassociated with any evidence of optic nerve damage was reported in a single patient with megalocornea. 21 Whereas there is an increased risk for the development of glaucoma in patients with pigment dispersion syndrome compared with normal adults of the same age group, 22 it is not known whether megalocornea with its related pigment dispersion shares a similar risk for developing glaucoma. There is a lack of evidence in the literature to either support or disprove an association between megalocornea and acquired glaucoma, and a prospective long-term follow-up study of these patients would be helpful in determining this risk. Our patients did not show a progressive increase in intraocular pressure with time even with the occurrence of pigment deposition in the trabecular mesh- 16 JANUARY/FEBRUARY 2004/VOL 41 NO 1

7 work. The intraocular pressures may be underestimated due to the relatively thin corneas in these patients, and close observation of the optic nerve head as well as visual fields in older children is essential in detecting the development of glaucoma in patients with megalocornea. Keratoglobus is a rare ectatic corneal defect resulting in bilateral, remarkably thin corneas with generalized anterior globoid protuberance. It may be associated with brittle cornea syndrome or Ehlers Danlos type VI disease, both of which have an autosomal recessive mode of inheritance This condition with remarkable prominence of the cornea must also be differentiated diagnostically from megalocornea and glaucoma (Table 2). In contrast to both megalocornea and infantile glaucoma, children affected with keratoglobus have bilateral diffusely thin corneas that protrude anteriorly in a marked and generalized globoid manner, with only a modest increase in the actual corneal diameter. In addition, these children frequently have blue sclerae and corneal ruptures following minor trauma Irregular corneal scarring is often present, which also helps to differentiate keratoglobus from the beautiful clear corneas seen with megalocornea. In addition to these features, keratoglobus can also be distinguished from both glaucoma and primary megalocornea by the systemic associations and family history of red hair or sensorineural deafness in brittle cornea syndrome as well as joint and skin laxity in Ehlers Danlos disease (Table 2) REFERENCES 1. Meire FM. Megalocornea: clinical and genetic aspects. Doc Ophthalmol 1994;87: Santolaya JM, Grijelbo A, Delgado A, Erdozain G. Additional case of Neuhauser megalocornea and mental retardation syndrome with congenital hypotonia. Am J Med Genet 1992;43: Koenekoop R, Rosenbaum K, Traboulsi E. Ocular findings in a family with Sotos syndrome (cerebral gigantism). Am J Ophthalmol 1995;119: Rogers GL, Polomeno RC. Autosomal-dominant inheritance of megalocornea associated with Down s syndrome. Am J Ophthalmol 1974;78: Vail D. Adult hereditary megalophthalmos sine glaucoma: a definite disease entity. Arch Ophthalmol 1931;6: Young AI. Megalocornea and mosaic dystrophy in identical twins. Am J Ophthalmol 1968;66: Duke-Elder S. Congenital deformities. In: System of Ophthalmology, vol. 3. St. Louis: Mosby; Laibson PR, Rapuano CJ. Diseases of the cornea. In: Nelson LB, ed. Harley s Pediatric Ophthalmology, ed. 4. Philadelphia: W. B. Saunders; Starck T, Hersh PS, Kenyon KR. Corneal dysgeneses, dystrophies and degenerations. In: Albert DM, Jakobiec FA, eds. Principles and Practice of Ophthalmology. Philadelphia: W. B. Saunders; Mackey DA, Buttery RG, Wise GM, Denton MJ. Description of X-linked megalocornea with identification of the gene locus. Arch Ophthalmol 1991;109: Pearce W. Autosomal dominant megalocornea with congenital glaucoma: evidence for germ-line mosaicism. Can J Ophthalmol 1991;26: Verloes A, Journel H, Elmer C, et al. Heterogeneity versus variability in megalocornea-mental retardation (MMR) syndromes: report of new cases and delineation of 4 probable types. Am J Med Genet 1993;46: Kraft SP, Judisch GF, Grayson DM. Megalocornea: a clinical and echographic study of an autosomal dominant pedigree. J Pediatr Ophthalmol Strabismus 1984;21: Van den Berg TJ, Ijspeert JK, de Waard PW, Meire F. Functional quantification of diaphany. Doc Ophthalmol 1990;75: Meire F, Delleman J. Biometry in X-linked megalocornea: pathognomonic findings. Br J Ophthalmol 1994;78: Lazaro G, Garcia F, Cuina S, et al. Sindrome de dispersion pigmentaria en paciente con megalocornea. Arch Soc Esp Oftalmol 2000;75: Saatci A, Soylev M, Kavuku S, Durale I, Saatci I, Memisoglu B. Bilateral megalocornea with unilateral lens subluxation. Ophthalmic Genet 1997;18: Malbran E, Dodds R. Megalocornea and its relation to congenital glaucoma. Am J Ophthalmol 1960;49: Friedmann AI, Etzine S. Familial coexistence of congenital glaucoma and megalocornea. Ophthalmologica 1984;62: Yen M, Gedde S, Flynn J. Unilateral glaucoma in Sotos syndrome. Am J Ophthalmol 2000;130: Topouzis F, Karodimas P, Gatzonis S, Bouzas E. Autosomal-dominant megalocornea associated with ocular hypertension. J Pediatr Ophthalmol Strabismus 2000;37: Siddiqui Y, Ten Hulzen RD, Cameron D, Hodge DO, Johnson DH. What is the risk of developing pigmentary glaucoma from pigment dispersion syndrome? Am J Ophthalmol 2003;135: Biglan A, Brown S, Johnson B. Keratoglobus and blue sclera. Am J Ophthalmol 1997;83: Izquierdo L, Mannis M, Marsh P, Yang S, McCarty J. Bilateral spontaneous rupture in brittle cornea syndrome: a case report. Cornea 1999;5: Stein R, Lazar M, Adam A. Brittle cornea: a familiar trait associated with blue sclera. Am J Ophthalmol 1970;66: JOURNAL OF PEDIATRIC OPHTHALMOLOGY & STRABISMUS 17

8 CME Quiz I N S T R U C T I O N S 1. Review the stated learning objectives on the first page of the CME article and determine if these objectives match your individual learning needs. 2. Read the article carefully. Do not neglect the tables and other illustrative materials, as they have been selected to enhance your knowledge and understanding. 3. The following quiz questions have been designed to provide a useful link between the CME article in the issue and your everyday practice. Read each question, choose the correct answer, and record your answer on the CME REGISTRATION FORM at the end of the quiz. 4. Type or print your full name and address and your date of birth in the space provided on the CME REGISTRATION FORM. 5. Complete the Evaluation portion of the CME Registration Form. Forms and quizzes cannot be processed if the Evaluation portion is incomplete. 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There are no specific background requirements for participants taking this activity. Primary Megalocornea: Clinical Features for Differentiation From Infantile Glaucoma 1. When asymmetric and large corneas are detected in childhood, an eye evaluation is indicated: A. To rule out strabismus. B. To rule out infantile glaucoma. C. To rule out hyperthyroid disease. D. To rule out a craniofacial synostosis syndrome. 2. The presence of enlarged and opacified corneas is characteristic of: A. Infantile glaucoma. B. Primary megalocornea. C. Keratoglobus. D. Neonatal herpes S. keratitis. 3. The most constant iris characteristic associated with primary megalocornea is: A. Corectopia. B. Posterior bowing. C. Hypoplasia. D. Hole formation. 4. Breaks in Descemet s membrane are an important diagnostic sign of: A. Primary megalocornea. B. Primary infantile glaucoma. C. Primary megalocornea with Down s syndrome. D. Rubella keratitis. 5. What explains that primary megalocornea is often familial and most often expressed in males: A. A suspected nutritional or infectious etiology. B. An X-linked recessive gene defect. C. Autosomal dominant transmission. D. Linkage with the fragile X-syndrome. 6. What component in the evaluation of a 2-year-old boy with abnormally large clear corneas should be considered most important: A. Slit-lamp examination. B. Funduscopy. C. Tonometry. D. Refraction. 7. What iris abnormalities help identify primary megalocornea: A. Congenital ectropion uveae and anterior iris insertion. 46 JANUARY/FEBRUARY 2004/VOL 41 NO 1

9 R E G I S T R A T I O N F O R M B. Corectopia and polycoria. C. Lens iris pupillary membrane and microcoria. D. Posterior bowing, transillumination, and iridodonesis. 8. What systemic condition has NOT been identified as associated with primary megalocornea: A. Down s syndrome. B. Marfan s syndrome. C. Soto s syndrome. D. CHARGE syndrome. 9. Which condition is NOT characterized by enlargement of the eyes: A. Marfan s syndrome. B. High myopia. C. Primary megalocornea. D. Primary congenital glaucoma. 10. Which condition has NOT been associated with anterior segment pigment dispersion: A. Pigmentary glaucoma. B. Primary megalocornea. C. Primary infantile glaucoma. D. Pigment dispersion syndrome. Black out the correct answers 1. A B C D 2. A B C D 3. A B C D 4. A B C D 5. A B C D Questions about CME and the Journal? Call us at or write to: Journal of Pediatric Ophthalmology & Strabismus PO Box 36 Thorofare, NJ JANUARY/FEBRUARY 2004 NO PAYMENT REQUIRED Primary Megalocornea: Clinical Features for Differentiation From Infantile Glaucoma 6. A B C D 7. A B C D 8. A B C D 9. A B C D 10. A B C D Number of hours you spent on this activity (reading article and completing quiz) Forms can be sent by fax to Deadline for mailing: For credit to be received, the envelope must be postmarked no later than February 15, PRINT OR TYPE Date of Birth: (used for tracking credits ONLY) Last Name First Name Degree Mailing Address City State Zip Code Phone Number Evaluation (must be completed in order for your CME Quiz to be scored) JANUARY/FEBRUARY 2004 Check the appropriate box below. Yes No 1. The objectives were useful to me in determining if this article would be a worthwhile educational activity for me. 2. The objectives accurately described the content and potential learning of this article. a. To identify the defining diagnostic signs of primary megalocornea. b. To compare primary megalocornea, infantile glaucoma, and keratoglobus to enable their differentiation in the evaluation of children with enlarged corneas. c. To summarize the literature related to primary megalocornea and to become more familiar with the associated ocular signs and potential associated diseases. 3. This activity will influence how I practice ophthalmology. a. If you answered yes, list one new thing you learned as a result of this activity. 4. The quiz questions were at an appropriate level for assessing my learning. 5. List topics you would like to see future CME activities address:. Office Use Only: Payment rec d Y/N; Evaluation completed Y/N; Score ; Entered Y/N Journal: Internet CODE:JPOS-0104 JOURNAL OF PEDIATRIC OPHTHALMOLOGY & STRABISMUS 47