Ocular abnormalities and complications in anterior megalophthalmos: a case series

Anterior megalophthalmos in sisters with Witteveen-Kolk syndrome

Anterior megalophthalmos is a form of anterior segment dysgenesis characterized by megalocornea (>12.5 mm) coupled with an enlarged lens-iris diaphragm and ciliary body ring. Importantly, intraocular pressure (IOP) is normal, and in contrast to buphthalmos, the ratio of anterior segment to vitreous cavity measurements is increased. Anterior megalophthalmos may be an isolated ocular finding, or it may be associated with syndromes such as albinism, Down syndrome, Frank-Ter-Haar, Marfan, Neuhauser, mucolipidosis type 2, and osteogenesis imperfecta. We report anterior megalophthalmos in 2 sisters with genetically confirmed (SIN3A, c.1657C>T, p.R553∗) Witteveen-Kolk syndrome (OMIM #613406).

Atypical presentations of non-familial anterior megalophthalmos: a rare disease

Anterior megalophthalmos usually presents early in life with megalocornea, deep anterior chamber, raised intraocular pressure, glaucomatous optic nerve damage and iridodonesis/stromal thinning with positive family history. We report atypical features and presentations in two patients (four eyes) with non-familial megalophthalmos. While the first patient, a male, presented at 51 years of age with megalocornea, cataract, phacodonesis, normal pupillary dilatation/normal iris and advanced glaucoma, the second patient presented with iridodonesis with stromal thinning, aphakia and advanced glaucoma. The family history was negative in both patients. The vitreous index was unusually high, >70% in all four eyes, owing to aphakia in the second patient and possible late presentation/variant phenotype in the first patient. Thus, atypical features such as greater vitreous length, absent iris involvement and late-onset adult presentation are common in non-familial anterior megalophthalmos. Clinical surprises due to varied phenotypes should be kept in mind in such cases.

Megalocornea, anterior megalophthalmos, keratoglobus and associated anterior segment disorders: A review

Megalocornea and anterior megalophthalmos (megalocornea spectrum) disorders are typically defined by corneal diameter > 12.5 mm in the absence of elevated intraocular pressure. Clinical features overlap with keratoglobus but are distinct from buphthalmos and severe (globus) keratoconus. Megalocornea spectrum disorders and keratoglobus are primarily congenital disorders, often with syndromic associations; both can present with large and thin corneas, creating difficulty in diagnosis, however, only keratoglobus is typically progressive. Molecular genetics provide significant insight into underlying aetiologies. Nonetheless, careful clinical assessment remains intrinsic to diagnosis. Surgical management can be challenging due to the enlarged ciliary ring and weakened zonules in megalocornea spectrum disorders and the extreme corneal thinning of keratoglobus. In this review, the established literature on measurement of corneal diameter, diagnosis of megalocornea, anterior megalophthalmos and keratoglobus, differentiation from severe keratoconus, recent molecular genetics research and key surgical modalities in the management of these rare disorders are outlined and discussed.

Epiblepharon in a Case of Anterior Megalophthalmos: A Diagnostic Red Herring

Epiblepharon is a condition characterized by the presence of a congenital horizontal fold of skin near the upper or lower eyelid margin and rarely requires intervention. In this communication, we present the case of a five-month-old child who had enlarged eyes, tearing, and intense photophobia; and was referred to as a case of congenital glaucoma. Congenital or infantile glaucoma can, indeed present with enlarged eyes, watering, and photophobia. However, in the absence of optic disc cupping and elevated intraocular pressures, a diagnosis of anterior megalophthalmos should be considered, especially in the presence of a very deep anterior chamber. Subsequent evaluation in our case established the diagnosis of anterior megalophthalmos along with concomitant bilateral epiblepharon. The child underwent surgery to correct the epiblepharon, following which, the tearing and photophobia resolved. The clinical characteristics of anterior megalophthalmos and the causality between an enlarged globe and epiblepharon are discussed in this article.

How many challenges we may encounter in anterior megalophthalmos with white cataract: a case report

Background

Anterior megalophthalmos is a rare congenital disease which mainly features enlargement of the anterior segment. Cataract surgeries in anterior megalophthalmos can be challenging due to the anatomical anomalies while the studies upon the surgical design have been less integrated.

Case presentation

A 37-year-old woman presented with progressively blurred vision in the right eye after a transient fever 10 months ago. Her ocular history included hypermetropia with a spherical equivalent of + 4.00 OU. The review of systems showed bilateral varus deformity of distal interphalangeal joints on the little fingers. The patient denied family history of hereditary ocular diseases and her sister was born with uterus didelphys. On initial examinations, the corrected distance visual acuity was hand motion OD and 20/33 OS. Her intraocular pressure was 15 mmHg OD and 16 mmHg OS. Horizontal corneal diameter was 14 mm OD and 13.88 mm OS and axial length was 24.87 mm OD and 25 mm OS. Anterior segment photography showed bilateral iridal atrophy with deficiency in pupillary dilation and white cortically mature cataract in the right eye. Inspection by anterior segment optical coherence tomography indicated bilateral augmented anterior chambers with backward iridal concave on horizontal orientation. Ultrasound biomicroscopy showed partially peripheral anterior synechiae and pectinate ligaments at chamber angle in both eyes and opacified lens with the apparently elongated suspensory ligaments in the right eye. A deliberately selected 1-piece foldable intraocular lens (IOL) with frame haptics was implanted after phacoemulsification for good IOL stability. During the follow-up, the visual rehabilitation appeared relatively good and a lower degree of IOL dislocation comparing with existing reports was verified by OPD-Scan III aberrometry.

Conclusions

We presented the challenges and the original findings from a case of congenital anterior megalophthalmos with white cataract who underwent phacoemulsification and IOL implantation. This is the first report describing the comparison of the different IOL power calculation formulas in anterior megalophthalmos. Compared to the SRK/T and the Holladay II formulas, the Haigis formula could be a more accurate choice for the IOL calculation in anterior megalophthalmos according to our case. Moreover, the deliberate selection of IOLs is essential for IOL stability in these patients.