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Head and Neck Muscles
Published in Eve K. Boyle, Vondel S. E. Mahon, Rui Diogo, Handbook of Muscle Variations and Anomalies in Humans, 2022
Eve K. Boyle, Vondel S. E. Mahon, Rui Diogo, Warrenkevin Henderson, Hannah Jacobson, Noelle Purcell, Kylar Wiltz
The absence of medial rectus may be associated with divergent strabismus (Macalister 1875; Le Double 1897; Lee et al. 2013). A bifid insertion of medial rectus may contribute to intermittent distance exotropia (Sundaram et al. 2005). An accessory medial rectus muscle may be present in cases of strabismus fixus convergens (Lee and Kim 2009). An inferiorly shifted insertion of medial rectus may be associated with microcornea and iris coloboma (Matsuo et al. 2009).
Arthropod-borne virus encephalitis
Published in Avindra Nath, Joseph R. Berger, Clinical Neurovirology, 2020
Zika virus can be transmitted perinatally. The virus can be detected in amniotic fluid, placenta and fetal brain tissue. Congenital zika is classically characterized by microcephaly with craniofacial disproportion, redundant occipital scalp skin, and brain imaging abnormalities, which include decreased brain volume, ventriculomegaly, cortical malformations, calcifications in gray and white matter and an enlarged cisterna magna [108]. Arthrogryposis has been observed in 11% of affected children [109]. Ocular complications of congenital zika infection are seen in 70% of infected children [110]. Ocular abnormalities include iris coloboma, lens subluxation, cataract, congenital glaucoma, and especially posterior segment findings [110].
Ophthalmology
Published in Stephan Strobel, Lewis Spitz, Stephen D. Marks, Great Ormond Street Handbook of Paediatrics, 2019
A rare abnormality of the shape of the pupil. Congenital causes include persistent pupillary membranes, iris coloboma, iris hypoplasia and ectopia lentis et pupillae (see below). Acquired causes include posterior synechiae seen in iritis or trauma.
Continuous Curvilinear Capsulorhexis – A Practical Review
Published in Seminars in Ophthalmology, 2022
Coloboma is a congenital condition in which part of the normal ocular tissue is missing, due to incomplete closure of the embryonal fissure.44 The clinical significance and implications for cataract surgery varies according to the involved eye structures.55 Lens coloboma is caused by incomplete zonular differentiation during the embryonal period, and is often an isolated finding.55 The zonular defect results in diminished or asymmetrical tension on the capsule, alterations in capsular volume and form, and the crystalline lens is therefore often harder, more prone to subluxation or dislocation, and advanced nuclear cataract can develop at young age.44 Hence, lens coloboma, as well as uveal coloboma which affects the iris, can complicate capsulorhexis with a higher risk of rhexis extensions, posterior capsular tears and vitreous loss during rhexis formation and phacoemulsification.44,45 Iris hooks or implementation of a capsular tension ring could facilitate cataract extraction, but their use requires a well sized and shaped CCC.22,44,54,55 Repair of iris coloboma along with cataract extraction is possible, but it probably does not improve the functional result and can be done for cosmetic reasons.44
Identification of a novel de novo variant in OTX2 in a patient with congenital microphthalmia using targeted next-generation sequencing followed by prenatal diagnosis
Published in Ophthalmic Genetics, 2022
Maryam Rafati, Faezeh Mohamadhashem, Koosha Jalilian, Fatemeh Hoseininasab, Laya Fakhri, Azadeh Hoseini, Hosna Amiri, Zeinab Barati, Somayeh Darzi Ramandi, Nioosha Mostofinezhad, Amir Hosein Mahmoudi, Saeed Reza Ghaffari
The proband was a 23-year-old male with congenital blindness. Clinical observations of the patient at two months of age are the following: the patient’s right eye had a horizontal corneal diameter of 6 mm and a Schiøtz tonometer reading of 6 mmHg. The right eye exhibited total blindness with no light perception. Microcornea and sclerocornea were detected. Further observations of the interior anatomy of the eye were hindered by sclerocornea. Clinical findings of the left eye are as follows: horizontal corneal diameter and intraocular pressure were measured to be 5 mm and 10 mmHg respectively. The left eye exhibited normal pupillary light reflex as well as a normal and clear lens. Iris coloboma and microcornea were observed. Large chorioretinal coloboma was observed in the fundus examination. The left eye displayed reduced depth of the anterior chamber. Extensive choroidal coloboma was found in the inferonasal region. Pigmentary changes in the macula were noted. Albinoid fundus appearance and pale optic disks were observed, which could be an indication of optic nerve atrophy. High level of hyperopia with +31 diopter refraction was detected.
An unusual ophthalmic presentation of Wolf-Hirschhorn syndrome
Published in Ophthalmic Genetics, 2021
Gökhan Çelik, Bilge Batu Oto, Osman Kızılay, Oğuzhan Kılıçarslan, Handan Hakyemez Toptan
Wolf-Hirschhorn Syndrome is developmental disorder characterized by craniofacial abnormalities, heart defects, skeletal and urogenital defects. The incidence of WHS is about 1/50.000–100.000 in live births and is twice more often in females (1). WHS is caused by deletion of the short arm of 4th chromosome. A recent study suggested neural crest motility and migration defects during development as a pathophysiology for WHS (2). Each patient presents with a unique combination of WHS characteristics, the severity of the phenotype in WHS depends on the extent of deletion area (3). Ophthalmic manifestations occur in approximately 40% of the patients (1). Refractive errors, epicanthus, hypertelorism, strabismus, ptosis, proptosis, colobomas of the eyelid and microphthalmia can be seen. Glaucoma, microcornea and iris coloboma can be observed. Foveal hypoplasia, colobomas of retina, choroid and optic nerve are the manifestations of posterior segment (4).