0 Ophthalmic Genetics 0167-6784/97/

us$12.00 subluxation Bilateral megalocornea with unilateral lens

Ophthalmic Genetics- 1997, Vol. 18,

0 Bolus Press Buren (The Netherlands) 1997

NO. I pp. 35 - 38

Accepted 7 October 1996

Ali Osman Saatci' Meltem Soylev' Salih Kavukcu2 ismet Durak'

IqiI saatci3 Berker Memisoglul

Departments of 'Ophthalmology and 'Pediatrics, Dokuz Eylul, lzmir and 3Department of Neuroradiology, Hacettepe University, Ankara, Turkey

Abstract Megalocornea refers to an enlarged cornea that measures 13 mm or more in horizontal diameter in the absence of raised intraocular pressure. We describe a five-month-old boy with bilateral megalocornea with unilateral lens subluxation. No other ophthalmological abnormality was present. In all previously reported cases with megalocornea and ectopia lentis, the lens was cataractous and the dislocation was in the inferior and posterior direction. In contrast, our case had a clear lens which was displaced superonasally.

Correspondence to: A. Osman Saatci, Mithatpasacad 9117,35330 BalGova7 izmir, Turkey. Fax 9°-232-2590541

Key words Congenital glaucoma; lens subluxation, megalocornea

Introduction The term megalocornea refers to an enlarged cornea that measures 13 mm or more in horizontal diameter in the absence of raised in- traocular pressure.' Megalocornea can be associated with ocular abnormal- ities such as myopia, high astigmatism, anterior embryotoxon, and Kruken- berg spindle.2 The condition is usually harmless except for three complica- tions that may appear later in life: lens subluxation; glaucoma secondary to associated anomalies of the angle; and ~ a t a r a c t . ~ We describe an infant with an unusual presentation of unilateral lens subluxation with bilateral megalo- cornea.

Case report A male infant was examined at five months of age because of enlarged corneas detected by his pediatrician. He was the product of a term, uncomplicated first gestation. Delivery and perinatal course were uncompli- cated. Family history was unremarkable and there was no consanguinity of the parents.

On examination, the patient had good ocular motility and was able to fol- low a light with either eye. The corneal diameters were equal and 13 mm (Fig. I). The right lens was displaced superonasally and the pupil was just barely covering the inferior edge of the lens before dilation. Cycloplegic reti-

Lens subluxation 35

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Fig.. with

I . Facial appearance of the bilateral megalocornea.

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noscopy was + 0.50 + 1.0 x 90° 0s. We could not measure the precise refrac- tion of OD due to lens displacement, but presumed cycloplegic refraction was -2.0 OD. Both fundi were normal. Ultrasonography showed normal globes with an axial length of 19.3 and 19 mm, respectively. Unfortunately, anterior chamber depth and vitreous length were not calculated separately at that time. Full pediatric examination, neurological evaluation, and laboratory values were normal. Examination under general anesthesia was performed to rule out congenital glaucoma. Except for right unilateral lens subluxation with bilateral megalocornea, no further change was noticed (Fig. 2). The ante- rior chamber angle and iris were normal. The intraocular pressure was 11 mmHg bilaterally without any sign of glaucoma. Magnetic resonance ima- ging showed no intraorbital and intracranial abnormality (Fig. 3). Minimal occlusion was recommended for the left eye and we believe that he could at least see at near with OD and did not develop amblyopia. During the six- month follow-up, no sign of glaucoma or squint was observed. No ocular ab- normality was detected in the ophthalmological examination of his parents.

Discussion Recognition of lens dislocation at any age requires further investigation to rule out hereditary syndromes that (are fatal or) have signifi- cant morbidity if not treated appropriately. In a group of 310 children requir- ing surgery for lens dislocation, Seetner and Crawford4 found that 16 had Marfan’s syndrome, seven idiopathic ectopia lentis, four homocystinuria, two ectopia lentis et pupillae, and one a hereditary condition of unknown type. Although the coexistence of megalocornea and ectopia lentis is just briefly described in some classic textbooks, we believe that unilateral lens sub- luxation is a very rare occurrence in megal~corneal-~

Lens subluxation progresses usually in an upward or up and out direction in Marfan’s syndrome, in a downward direction in homocystinuria, and in an upward and temporal direction in simple ectopia l e n t i ~ . ~ In the literature, only five cases of lens subluxation out of 106 patients with megalocornea have been In all these cases, the lens was cataractous and disloca- tion was in the inferior and posterior direction. In a very recent study on

36 A. 0. Saatci et al.

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Fig. 2 . Superonasal lens subluxation in the right eye. Fig. 3. Axial MRI scans showing nasal displacement of the right lens (arrow).

megalocornea, Meire" supposed that it was likely that if lenses became cataractous they tended to subluxate. Most notably, the lens was clear and subluxated superonasally in our case.

The major concern in our patient was amblyopia due to anisometropia or monocular diplopia. If the lens is displaced minimally, lenticular myopia may occur because of increased curvature as a result of relaxation of the suspen- sory ligament and tilting of the lens causing a marked irregular astigma- tism." Monocular diplopia may also be caused by the lens being partly in and partly out of the pupil.

Genetic counseling was also our second concern as our patient was the first child in his family. The probable mode of inheritance was X-linked, although autosomal dominant cases of megalocornea have also been reported." Ge- netic counseling may, however, be extremely difficult."

We believe that our case represents a very rare association of bilateral megalocornea with unilateral lens subluxation without any significant ocu- lar complications.

References Louis: The C.V. Mosby Company 1983; 33.

3 Wilson I1 FM. Congenital anomalies. In: Smolin G, Thoft RA, editors. The Cornea. Boston: Little, Brown and Company 1987; 457-413.

I Duke-Elder S. System of Ophthal- mology. London: Kimpton 1964; 498 - 501.

z Grayson M. Diseases of the Cornea. St

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4 Seetner AA, Crawford JS. Surgical cor- rection of lens dislocation in children. Am J Ophthalmol 1981; 91: 106-110.

5 Nelson LB, Maumenee IH. Ectopia lentis. Sum Ophthalmol 1982; 27: I43 - 159.

6 Dohlman CH, Larsson S. Megalo- cornea and cataract. Acta Ophthalmol 1958; 36 845- 848.

7 Rud E. Megalocornea in a Danish gipsy family. Acta Ophthalmol1960; 38: 606- 617.

8 Skuta GL, Sugar J, Ericson ES. Corneal endothelial cell measurements in mega- locornea. Arch Ophthalmol1983; 101: 51-53.

9 Huet F, Castier Ph, Langlois M,Woillez JPh, Degrave B. La megalocornee heredo-familiale. Bull SOC Ophtalmol 1987; 87: 835- 838.

10 Meire F. Megalocornea. Doc Ophthalmol 1994; 87: 1-121.

11 JaRe NS, Jaffe MS, Jaffe GF. Cataract Surgery and Its Complications. St Louis: The C.V. Mosby Company 1990; 303-316.

12 Bjerrum K, Kessing SV. Congenital ectopia lentis and secondary buphthalmos likely occurring as an autosomal recessive trait. Acta Ophthalmol 1991; 69: 630-634.

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