Bilateral Chorioretinal Coloboma Research Articles

CHARGE syndrome presenting with persistent hypoglycemia: case report and overview of the main genetic syndromes associated with neonatal hypoglycemia

BackgroundCHARGE syndrome (CS) is an autosomal dominant genetic condition whose recognition in the neonatal period is complicated by considerable phenotypic variability. Pediatric patients with genetic disorders have a known high incidence of hypoglycemia, due to many concurring factors. To date, neonatal hypoglycemia is a feature poorly explored in the literature associated with CS. This paper adds to the existing literature on hypoglycemia in CS and provides a brief review of the mechanisms through which CS, as well as the main genetic syndromes associated with neonatal hypoglycemia, may determine it.Case presentationThe patient was a term newborn, first-born daughter to non-consanguineous parents. At birth, axial hypotonia with slight hypertonia of the limbs, and dysplastic auricles were noted. The incidental finding of asymptomatic hypoglycemia led to the initiation of glucose infusion on the II day of life, continued for a total of 8 days (maximum infusion rate: 8 mg/kg/min). In-depth endocrinological examinations showed poor cortisol response to the hypoglycemic stimulus, with normal GH values, thyroid function and ACTH. In view of the suspected hypoadrenalism, oral hydrocortisone therapy was initiated. Inappropriately low values of plasmatic and urinary ketones supported the hypothesis of concomitant transient hyperinsulinism, not requiring therapy. A brain MRI was performed, documenting thinning of the optic nerves, non-displayable olfactory bulbs and dysmorphic corpus callosum. An eye examination revealed bilateral chorioretinal coloboma. Temporal bone CT scan showed absence of the semicircular canals. The unexpected findings of coloboma and absence of semicircular canals led to the suspicion of CS, later confirmed by the molecular analysis of CHD7.ConclusionsIt seems important to consider CS in the differential diagnosis of persistent hypoglycemia in newborns with specific anomalies. At the same time, it is advisable to consider the risk of hypoglycemia in children with CS, as well as other genetic syndromes. Awareness of the many possible causes of hypoglycemia in newborns with genetic conditions may help steer the investigations, allowing for an appropriate and timely treatment.

Low-vision aids improve the visual performance of children with bilateral chorioretinal coloboma

To quantify the improvements in visual performance for both distance and near tasks attained by children with bilateral chorioretinal coloboma (CRC) with use of low-vision aids (LVAs). This was a hospital-based, cross-sectional, interventional case series of children with bilateral CRC. Demographic data were collected through a structured questionnaire and review of medical records. Distance and near best-corrected visual acuity, contrast sensitivity, and reading speed were evaluated with refractive correction alone and with the use of LVAs (Keplerian telescopes for distance; handheld magnifiers and a tinted lens [400nm filter] for near). Effects are presented as medians of differences with 95% binomial-exact confidence intervals. Six children were included (median age, 11.5years; range, 7-17years), of whom 5 were already using LVAs on a daily basis. The use of a Keplerian telescope achieved a significant median improvement in distance best-corrected visual acuity of 0.75 logMAR (95% CI, 0.20-1.20). Contrast sensitivity was also improved across all tested spatial frequencies. Use of near LVAs resulted in a significant median improvement in near reading acuity of 0.47 logRAD (95% CI, 0.28-0.90). Critical print size and reading speed at N10 were also improved. LVAs enable meaningful improvements in the visual performance of children with bilateral CRC, allowing noteworthy increases in distance and near visual acuities as well as good reading speeds at small print sizes.

Atypical Retinal Lamination Pattern Associated with Bilateral Chorioretinal Coloboma

Atypical Retinal Lamination Pattern Associated with Bilateral Chorioretinal Coloboma

New variant and expression studies provide further insight into the genotype-phenotype correlation in YAP1-related developmental eye disorders

YAP1, which encodes the Yes-associated protein 1, is part of the Hippo pathway involved in development, growth, repair and homeostasis. Nonsense YAP1 mutations have been shown to co-segregate with autosomal dominantly inherited coloboma. Therefore, we screened YAP1 for variants in a cohort of 258 undiagnosed UK patients with developmental eye disorders, including anophthalmia, microphthalmia and coloboma. We identified a novel 1 bp deletion in YAP1 in a boy with bilateral microphthalmia and bilateral chorioretinal coloboma. This variant is located in the coding region of all nine YAP1 spliceforms, and results in a frameshift and subsequent premature termination codon in each. The variant is predicted to result in the loss of part of the transactivation domain of YAP1, and sequencing of cDNA from the patient shows it does not result in nonsense mediated decay. To investigate the role of YAP1 in human eye development, we performed in situ hybridisation utilising human embryonic tissue, and observed expression in the developing eye, neural tube, brain and kidney. These findings help confirm the role of YAP1 and the Hippo developmental pathway in human eye development and its associated anomalies and demonstrate its expression during development in affected organ systems.

Chorioretinal Coloboma Complications: Retinal Detachment and Choroidal Neovascular Membrane.

Purpose:To report the chorioretinal coloboma, and its association with increased risk of retinal detachment (RD) and choroidal neovascularization (CNV).Methods:This retrospective case series included eyes with chorioretinal coloboma diagnosed between 1995 and 2014 with a focus on RD and CNV as related complications. Cases of CNV were managed with laser photocoagulation or intravitreal injection of bevacizumab. For eyes with CNV, therapeutic success was defined as resolution of the subretinal hemorrhage on fundus examination and resolution of the subretinal and intraretinal fluid on optical coherence tomography (OCT). For eyes with RD, anatomic success following surgical intervention was defined as attachment of the retina at the last follow-up visit.Results:Fifty-one eyes of 31 patients with chorioretinal coloboma were identified for review. Bilateral chorioretinal coloboma was present in 64.5% of subjects. RD developed in 15 eyes (29.4%). Among 15 eyes with RD, 4 eyes (27%) had retinal breaks identified within the coloboma, 5 eyes (33%) had retinal breaks outside the coloboma, 2 eyes (13%) showed retinal breaks both inside and outside the coloboma, and in 4 eyes (27%) the causative retinal break was not localized. The overall rate of anatomic success after RD repair was 85.7%. CNV developed in 7 eyes (13.7%) and was located along the margin of the coloboma in all cases. CNV was bilateral in 2 of the 5 affected individuals (40%).Conclusion:RD and CNV were present in a high percentage of eyes with chorioretinal coloboma in these series. The frequent finding of retinal breaks outside the coloboma bed suggests that vitreoretinal interface abnormalities may play a role in development of RD in these eyes.

Çift Optik Disk İzlenimi Veren Bilateral Koryoretinal Kolobom Olgusu

Çift Optik Disk İzlenimi Veren Bilateral Koryoretinal Kolobom Olgusu

Two cases of CHARGE syndrome with multiple congenital anomalies

We report on two cases of bilateral chorioretinal colobomas with ocular anomalies in patients with CHARGE syndrome. In the first case, a female infant was born at 36 + 5 weeks gestation. At birth, the patient demonstrated a small left eye. Slit-lamp examination revealed colobomas of both irises. Fundus examination showed both chorioretinal colobomas. Brain magnetic resonance imaging (MRI) showed left microphthalmia. Systemic evaluation revealed multiple congenital anomalies: benign external hydrocephalus, esophageal atresia with imperforate anus, atrial septal defect (ASD), ventricular septal defect, patent ductus arteriosis (PDA), and right mild hydronephrosis. In the second case, a male infant was born at 39 + 5 weeks gestation and demonstrated a dysmorphic appearance with an irregular left pupil and ptosis. Fundus examination of both eyes showed large chorioretinal colobomas involving the optic disc and posterior pole. The patient had multi-organ anomalies: right facial palsy, a left short, wide ear with a small lobe, congenital heart defects, such as ASD and PDA, left renal atresia, seizure disorder, and micropenis. Both cases revealed multiple anomalies including nearly all major and minor criteria of CHARGE syndrome which could be life-threatening to neonates. Thus, all neonates with ocular colobomas should have fully and detailed systemic examinations checking all minor criteria and even occasional findings of CHARGE syndrome.

Bilateral chorioretinal coloboma discovered with ultra-wide field retinal imaging

Uveal coloboma results from incomplete closure of the optic cup fissure. While conducting an evaluation of a new ultra-wide field retinal imaging camera (Optomap), which provides a view of the fundus up to 200° at one time without mydriasis, we discovered a case of bilateral chorioretinal coloboma in a 21-year-old student. The lesion was located in the midperiphery of each eye less than 2disc diameters (DD) below the optic disc in the inferonasal quadrants. The size of the coloboma in the right eye was 1.8DD in height and 1.3DD in width, while the left lesion was 2.4DD in height and 2.6DD in width. The subject was totally asymptomatic and without any complication such as retinal detachment or choroidal neovascularization, which often accompany this type of lesion. The visual field of each eye displayed an absolute scotoma corresponding to the size and location of the coloboma. No management was necessary but the subject was advised to report for visual examination at regular intervals because complications can occur at any age.

Choroidal melanoma in a patient with congenital bilateral chorioretinal coloboma: a case report of an extremely rare association of ocular comorbities

Clinicopathologic findings of a 44-year-old Caucasian male who presented with a congenital bilateral chorioretinal coloboma and later developed a large choroidal melanoma in his best seeing eye. The eye containing the malignant tumor was enucleated and the histopathologic findings confirmed the clinical diagnosis of choroidal melanoma, and in this case, an epithelioid cell type.

Ocular features of CHARGE syndrome

To detail the presence and severity of ocular and cranial nerve abnormalities found in individuals with CHARGE syndrome in a distinct geographic area. Nine individuals with CHARGE syndrome from Maritime Canada identified from a Canadian database were prospectively examined. Structural and sensorial defects associated with functional visual deficits were defined with ophthalmic and neurological evaluation. Consistent with current diagnostic criteria and the literature, colobomas were the major ophthalmic manifestation. These were typically bilateral chorioretinal colobomas involving the optic nerve. All subjects had bilateral severe sensorineural deafness (cranial nerve VIII), and 8 of 9 (89%) had facial nerve (cranial nerve VII) involvement (7 of 9 had unilateral involvement; 1 of 9 had bilateral involvement). Unique to this group of participants were the findings of anisometropia in 8 of the 9 (89%) patients, severe myopic astigmatism in 13 of the 18 eyes (72%), and limited elevation in adduction in 3 of 9 (33%) participants. Associated findings were strabismus, cataracts, microcornea, keratopathy, staphyloma, reduced stereopsis, superior visual field defects, and reduced visual acuity. The presence of coloboma plus another CHARGE feature warrants further investigation, including genetic screening for the CHD7 gene. Early recognition and management of sensory problems (visual, auditory, and vestibular) are crucial to ensure best psychomotor and cognitive development.

The Joubert syndrome associated with bilateral chorioretinal coloboma

The Joubert syndrome associated with bilateral chorioretinal coloboma