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How to master MCQs
Published in Chung Nen Chua, Li Wern Voon, Siddhartha Goel, Ophthalmology Fact Fixer, 2017
Laser iridotomy is used in angle-closure glaucoma caused by pupillary block by providing an alternative pathway for the aqueous. Phacomorphic glaucoma is a common contributing factor in primary angle closure. Pupillary block can be caused by the abnormal spherical lens in microspherophakia. Iris bombe impair the flow of aqueous through the pupil and hence pupillary block. Phacolytic glaucoma is caused by the release of lens proteins into the drainage angle where they are engulfed by macrophages, leading to blockage of the trabecular meshwork. Malignant glaucoma is caused by aqueous misdirection into the vitreous cavity.
Ocular media
Published in Fiona Rowe, Visual Fields via the Visual Pathway, 2016
Congenital anomalies can produce disorders of the lens shape and position such as coloboma, micro-phakia, microspherophakia, lentiglobus and lenti-conus. Congenital cataract may be due to genetic, metabolic or chromosome defects.
The Developmental Glaucomas
Published in Neil T. Choplin, Carlo E. Traverso, Atlas of Glaucoma, 2014
Carlo E. Traverso, Alessandro Bagnis
Microspherophakia may occur as an isolated finding or in association with systemic syndromes (see below). Clinically, the edges of the small spheric lens can be seen through the mid-dilated pupil. Other typical findings are high myopia and a shallow anterior chamber in a young person. Zonular laxity can lead to pupillary block with acute or chronic angle closure. Miotics make the pupillary block worse because they result in further anterior lens displacement.
Bilateral angle closure glaucoma in a 28-year-old Cohen syndrome patient
Published in Ophthalmic Genetics, 2018
Ang Li, Alisha Gandhi, Heng Wang, Elias I. Traboulsi
On presentation, her right and left eye intraocular pressures (IOP) were 47 and 57 mmHg, respectively and visual acuity was 20/400 OD and 20/1000 OS. Slit-lamp examination revealed bilateral corneal haze, extremely narrow angles, and iris pupillary transillumination defects. The view of the posterior pole was difficult due to corneal haze, but we identified significant optic disc atrophy with 3+ optic nerve pallor OU. Gonioscopy demonstrated closed angles 360° in both eyes. An emergent Nd:YAG laser peripheral iridotomy (LPI) was performed in both eyes after pilocarpine instillation with an initial IOP drop to high 30’s mmHg. She returned the follow day with IOPs still in the mid-40’s mmHg OU and the anterior chambers were very shallow despite patent iridotomies. Given her high myopia, angle closure configuration, and persistent pupillary block despite patent iridotomies, a diagnosis of phacomorphic glaucoma from a subluxed lens or microspherophakia was entertained. Ultrasound biomicroscopy (Figure 1) showed bilateral 360° appositional closed angles that confirmed the diagnosis of phacomorphic angle closure. A decision was taken to perform emergent lens extraction as the patient was in significant pain and the IOP continued to be elevated. A-scan ultrasound biometry revealed axial lengths of 20.12 mm OS and 20.55 mm OD.
Corectopia grading: A novel classification system
Published in Seminars in Ophthalmology, 2022
Natalia Anisimova, Lisa Arbisser, Argyrios Tzamalis, Beáta Éva Petrovski, Natalya Shilova, Goran Petrovski, Sergey Anisimov, Boris Malyugin
Frequently, corectopia is associated with lens subluxation, an isolated condition referred to as ectopia lentis et pupillae.5 This predominantly bilateral alteration is associated with displacement of pupil and lens in the opposite directions.1 The pupils may be round, oval or slit-shaped: all commonly dilate poorly. Iris transillumination defects may also be present in that condition and is reportedly associated with microspherophakia.5 Progressive corectopia can be associated with a number of developmental syndromes such as iridocorneal endothelial (ICE) syndrome.6,7 Intermittent corectopia has also been described in a patient with bilateral, rostral midbrain infarction.8
Bilateral Subluxation of Microspherophakic Lens in a Child with Cohen Syndrome
Published in Journal of Binocular Vision and Ocular Motility, 2023
Elizabeth A. Chu, Alexandria Cummings, Nicholas Sala, Nicholas Sala
Here, we present the first documented case of a 5-year-old Amish child with Cohen Syndrome who presented with bilateral subluxation of microspherophakic lenses. Microspherophakia is a crystalline lens that has increased anteroposterior distance, reduced equatorial diameter, and is more spherical than a typical lens due to arrested development of secondary lens fibers. Microspherophakia is a rare genetic disorder that can be seen in isolation or as part of an autosomal anomaly. The exact prevalence is unknown, but a study of 1,047 children with lenticular abnormalities had a 1.5% frequency of children with microspherophakia.6 Of known cases in general, 44.4% have concurrent lens subluxation.7