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Homocystinuria
Published in William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop, Atlas of Inherited Metabolic Diseases, 2020
William L. Nyhan, Georg F. Hoffmann, Aida I. Al-Aqeel, Bruce A. Barshop
Homocystinuria represents a multisystem disorder with involvement of the eyes, integument, skeleton, vascular system, and nervous system [4, 6, 7]. Patients are born normal but in the untreated, severe form they develop the full constellation of clinical abnormalities within 2–6 years of life. Ectopia lentis is a striking and readily recognizable manifestation of the disease (Figures 18.2–18.5). It is often preceded by rapidly worsening myopia, which may be the only manifestation [4–8] and, by 38 years of age, only 3 percent of patients have both lenses in place. Dislocation is usually present by ten years of age. The dislocation is said to be usually, but not always, downward – the opposite of the situation in Marfan disease. Its presence may be signaled by iridodonesis, a dancing or shimmering of the iris. Electron microscopy reveals partially broken zonules, abnormal zonular attachment, and a spongy capsular appearance [8]. Complications may include dislocation into the anterior chamber and papillary block glaucoma (Figure 18.3). Other ocular abnormalities include myopia, optic atrophy, cataracts, or retinal detachment [9].
Management of traumatic lens subluxation and dislocation
Published in A Peyman MD Gholam, A Meffert MD Stephen, D Conway MD FACS Mandi, Chiasson Trisha, Vitreoretinal Surgical Techniques, 2019
The symptoms of a patient with a displaced lens depend on the position of the lens. The patient may complain of decreased vision caused either by acquired astigmatism and refractive shift or by acquired aphakia in cases of dislocation. Other symptoms are glare and monocular diplopia from the lens edge. A cataract will result in decreased visual acuity and contrast sensitivity (Fig. 48.1). Inflammation, glaucoma, and corneal edema can result in pain and photo-phobia. In cases of blunt injury, one must maintain a high degree of suspicion for an occult rupture. Special attention is paid to visual acuity, corneal status, degree of intraocular inflammation, and IOP. Lens subluxation is occasionally subtle. Zonular dehiscence is marked by the presence of iridodonesis and phacodonesis. The anterior chamber should be examined carefully for the presence of vitreous. The lens itself should be examined for breaks in the anterior and posterior capsule, along with the presence of cataract. One should also carefully evaluate the vitreous and retina for vitreous hemorrhage, retinal tears and detachments, and the presence of cystoid macular edema. Ultrasonography can be very helpful in evaluating the status of the retina and vitreous in eyes with opaque media, and a dislocated lens is easily diagnosed (Fig. 48.2). Computed tomography (CT) may also be helpful in evaluating the possibility of a dislocated lens.19
Further phenotypic characterization of LEPREL1-related ectopia lentis
Published in Ophthalmic Genetics, 2019
An 11-year-old Emirati girl was seen because of need for glasses since she was two years old. The parents were first cousins and noted that one of her three other siblings seemed similarly affected. The child had an evaluation to rule out diabetes because she tended to drink large amounts of water; that evaluation was negative. The parents denied other medical issues. Best-corrected visual acuity (−16.25–3.00x133, −20.50–3.00x019) was 20/25, 20/50. There was no strabismus or nystagmus and ocular motility was full. Pupillary exam and intraocular pressures were normal. Slit-lamp examination was remarkable for smooth cryptless irides, iridodonesis right eye, and superonasal crystalline lens subluxation left eye (Figure 1). Retinal exam revealed severe chorioretinal atrophy (Figure 2(a,b)). Ocular biometry showed the right eye to have a keratometry average of 42.80 with an axial length of 28.02 mm and the left have to have a keratometry average of 43.80 with an axial length of 28.66 mm.
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
A 5-year-old Amish female presented for initial evaluation at Pediatric Ophthalmology of Erie after her mother noticed her holding objects very close to her face. Given the patient’s non-verbal status, developmental delay, and diagnosis of Cohen Syndrome confirmed by genetic testing, a comprehensive evaluation by a pediatric ophthalmologist was requested to rule out visual and ocular abnormalities. The patient’s mother denied any noticeable strabismus, nystagmus, abnormal head posturing, trauma, or neurologic events. The patient’s mother did not have any lens abnormalities on examination, but the patient’s family history included a brother and six cousins with Cohen Syndrome. The patient was unable to perform quantitative visual acuity testing but was found to be central, steady, and maintained in each eye. She was able to fix and follow. Pupils were equal, round, and reactive with no afferent pupillary defects. Extraocular motility was full with normal alignment at distance and near. Anterior segment examination revealed significant iridodonesis in both eyes (OU) and lens subluxation greater in the right eye (OD) than the left eye (OS). Dilated examination confirmed bilateral lens subluxation and further revealed bilateral microspherophakia and nuclear sclerotic cataracts. The entirety of both lens’ borders was visible through the dilated pupils. It was noted that most of the zonular fibers were disrupted temporally causing the right lens to be subluxated nasally with the edge of the lens visible through the visual axis. There was apparent zonular laxity, as phacodonesis was present in the right lens greater than the left. Photos were attempted but unable to be obtained due to patient noncompliance. Retinoscopy was also attempted but cycloplegic refraction was unable to be obtained, as the reflex was poor secondary to the nuclear sclerotic cataracts and subluxated lenses. Fundus examination revealed mild signs of optic atrophy as well as peripheral pigment mottling in both eyes.
Expanding the clinical spectrum and management of Traboulsi syndrome: report on two siblings homozygous for a novel pathogenic variant in ASPH
Published in Ophthalmic Genetics, 2021
Tom Van Hoorde, Fanny Nerinckx, Elke Kreps, Dimitri Roels, Philippe Huyghe, Mattias Van Heetvelde, Hannah Verdin, Elfride De Baere, Irina Balikova, Bart P. Leroy
Patient IV.4 (proband) had noticed suboptimal visual acuity in both eyes as early as the age of 7. At presentation, sslit-lamp biomicroscopy revealed very shallow anterior chambers (Figure 1a), an atrophic appearance of both irides, iridodonesis and an anteriorly subluxated, microspherical, clear crystalline lens in both eyes. These findings were confirmed by UBM (Figure 1b). The posterior segment was unremarkable except for a marked cupping of the optic disc OU. Prophylactic YAG-laser peripheral iridotomies were created in both eyes to prevent angle closure glaucoma. These procedures initially altered neither IOP nor anterior chamber depth. However, on a scheduled follow-up visit 4 months later, IOP was 38 mmHg in the right eye despite that the anterior chamber had deepened at that time. The patient was asymptomatic and gonioscopy showed an open iridocorneal angle in the right eye (Figure 1c) and a subtotal closure of the angle in the left eye albeit that the intraocular pressure remained normal. Normal pressure was eventually achieved in the right eye with topical dorzolamide/timolol drops BID. Despite a patent iridotomy, the anterior chamber remained very shallow in the left eye with an open iridocorneal angle only obtained following pupillary dilation, potentially secondary to posterior rotation of the ciliary body. To prevent acute angle closure, a lensectomy using a limbal approach was performed by an experienced paediatric vitreoretinal surgeon in the left eye. Lensectomy was performed by a 27 g vitrectomy system, allowing clear corneal incisons of 0,4 mm. The bag was preserved and a posterior capsulorhexis was performed. The patient was left aphakic. Postoperatively, the anterior chamber deepened, IOP remained low and BCVA of 0.7 was obtained. So far, no surgery was performed on the right eye as the anterior chamber and iridocorneal angle were sufficiently deep, the peripheral iridotomy was open and IOP was low using only topical treatment. Drops were stopped 3 months later and IOP remained low normal thereafter. Rigid, gas-permeable contact lens fitting was subsequently performed and a VA of 0.6 OD and 0.9 OS was obtained. Optical coherence tomography of the optic disc showed preservation of the peripapillary nerve fiber layer.