Christiane Al-Haddad

Retinal nerve fibre layer and macular thickness in amblyopia as measured by spectral-domain optical coherence tomography

Background/aims To study peripapillary retinal nerve fibre layer (RNFL) and macular thickness in amblyopia using high-definition spectral-domain optical coherence tomography (SD-OCT) and to compare the results with available literature using the time-domain modality. Methods This was a prospective institutional study of patients ≥6 years of age with unilateral amblyopia (strabismic or anisometropic) and non-amblyopic anisometropia. RNFL and macular thicknesses were measured using SD-OCT and compared between fellow eyes. Results The mean age was 20 (±12) years; 45 patients had amblyopia: 14 strabismic and 31 anisometropic. 20 patients had non-amblyopic anisometropia. The mean macular thickness was significantly increased in the amblyopic (273.8 μm) vs fellow eyes (257.9 μm), p=0.001. This difference remained significant in the anisometropic group (p=0.002) but not the strabismic group. The mean RNFL thickness was similar in amblyopic (95.4 μm) and fellow eyes (94.0 μm). Similar results were obtained regardless of the level of visual acuity, age or refractive error. In the control group of non-amblyopic anisometropia, the interocular difference did not reach statistical significance. Conclusions Central macular thickness was significantly increased in anisometropic amblyopia using SD-OCT. Anisometropia alone did not produce such a difference, which points to a possible correlation between amblyopia and the development of the retinal layers.

Macular ultrastructural features in amblyopia using high-definition optical coherence tomography

Purpose To study macular morphology in amblyopic eyes using high-definition spectral domain optical coherence tomography (SD-OCT) and to compare the findings with fellow eyes. Methods This was a prospective institutional study of patients ≥6 years of age with unilateral amblyopia. Enhanced high-definition single line macular scans of amblyopic eyes were obtained using SD-OCT and compared with fellow eyes. Scans were evaluated qualitatively for structural differences. Central foveal thickness was measured and areas of the different retinal layers were computed within 500 µm from the foveal centre nasally and temporally. Results Forty-five patients with unilateral amblyopia were included: 25 with strabismic and 20 with anisometropic amblyopia with a mean age of 24.8 years. Qualitatively, the bulge in the inner segment/outer segment junction of the central fovea was noted to be attenuated or absent in 60% of amblyopic eyes compared with 29% of normal eyes, p=0.02. Also, amblyopic eyes demonstrated a shallow foveal pit compared with normal fellow eyes. Mean foveal thickness was significantly increased in amblyopic (228.56 µm) versus fellow eyes (221.72 µm), p=0.03. Upon exploring different retinal layers, the temporal inner nuclear layer area was increased (p=0.04) while the outer nuclear layer area was decreased (p=0.04) in amblyopic eyes compared with fellow eyes. Conclusions Using enhanced high-definition SD-OCT, amblyopic eyes demonstrated qualitative and quantitative differences in macular features, possibly representing signs of immaturity compared with normal fellow eyes.

Interocular symmetry in retinal and optic nerve parameters in children as measured by spectral domain optical coherence tomography

Background/aims To report interocular differences in retinal nerve fibre layer (RNFL), optic nerve head and macular parameters in children using spectral domain optical coherence tomography (SD-OCT). Methods This was an observational cross-sectional study including 108 healthy children aged 6–17 years with no ocular abnormality except refractive error. After a comprehensive eye exam and axial length measurement, RNFL, optic nerve and macular thickness measurements were performed using the Cirrus OCT machine. Right and left eyes were compared and interocular differences were computed. Subjects were also divided into two groups based on age (under or over 10 years of age). Main outcome measures were interocular differences and their correlations with age and gender. Results The study included 108 children, mean age 10.7±3.1 years; significant interocular differences were observed in both macular and RNFL parameters. The macular thickness analysis revealed interocular differences in the outer nasal and outer inferior quadrants, with left eyes displaying larger values. With respect to RNFL parameters, right eyes displayed thicker nasal and temporal quadrants, and inferior clock hours; left eyes had a thicker superior quadrant. The older age group (>10 years) had more pronounced variation in interocular differences compared with the younger group with less mature visual systems. Conclusions Normal variation in interocular symmetry exists. Our results can contribute to establishing a standard reference for interocular differences in OCT parameters in children aged 6–17 years using the Cirrus device.

Genotype/Phenotype Correlation in Primary Congenital Glaucoma Patients in the Lebanese Population: A Pilot Study

Abstract Background: The incidence of primary congenital glaucoma (PCG) varies among geographic regions and ethnic groups. The frequency of PCG in Lebanon and identification of disease-causing mutations have not been studied previously. Purpose: To investigate the role of Cytochrome P1B1 (CYP1B1) gene and Myocillin (MYOC) gene mutations in PCG in the Lebanese population and study possible genotype/phenotype correlations. Methods: Patients with unilateral or bilateral PCG diagnosed at the American University of Beirut Medical Center and their first-degree relatives (parents and siblings) were screened for CYP1B1 and MYOC mutations. Demographic and phenotypic characteristics were recorded. Phenotypic characteristics pertaining to disease severity and outcomes were compared. Results: Eighteen Lebanese families (66 subjects) with at least one member affected with PCG were included in this study. Mutations in the CYP1B1 gene were detected in 6 families (33%). Five previously described mutations (p.R444Q; p.E229K; p.R469W; p.G61E; p.M1T) and one new single nucleotide deletion were identified (1793delC). Patients in whom CYP1B1 mutations were detected tended to have a more severe phenotype as evidenced by earlier age at diagnosis, higher rate of bilateral disease, and higher number of glaucoma surgeries than those in whom no CYP1B1 mutations were present. MYOC gene mutations were not detected in any patients. Conclusion: The rate of CYP1B1 mutations in Lebanese patients with PCG is lower than that reported in other Arab and Middle Eastern populations and suggests other genes are responsible for PCG in the remainder.

Plasma thymulin and nerve growth factor levels in patients with primary open angle glaucoma and elevated intraocular pressure

BackgroundThe objective was to measure the plasma concentrations of thymulin and nerve growth factor (NGF) in a group of patients with primary open angle glaucoma (POAG) and compare them with age- and sex-matched normal controls.MethodsTwenty-eight patients newly diagnosed with POAG who were not undergoing treatment were compared with the same number of age- and sex-matched healthy controls. Blood samples were drawn into heparinized tubes and plasma samples were collected for the determination of the concentrations of thymulin and NGF, using specific enzyme-linked immunosorbent assay (ELISA). The Student’s t test was used to perform the necessary statistical analysis of the results.ResultsSeventeen women and 11 men were enrolled in each of the two groups (study and control), with a mean age of 63.7 (SD 10.3) years in the former and 63.3 (SD 9.6) years in the latter. There was a highly significant (p<0.001) elevation in the thymulin levels in POAG patients compared with the control group. However, no significant difference was observed when comparing the plasma NGF levels.ConclusionThis is the first report to measure plasma thymulin levels in glaucoma patients. The significant results point the possible role of this immunomodulator in the pathogenesis of primary open angle glaucoma. The potential role of NGF seems to be less likely. These findings warrant further investigation.

Vitrectorhexis and lens aspiration with posterior chamber intraocular lens implantation in spherophakia.

&NA; We describe a technique that uses the vitrector to perform successful lens aspiration and posterior chamber intraocular lens (IOL) implantation in children with spherophakia and anterior lens subluxation. After an anterior chamber maintainer is placed, the ocutome is introduced through a limbal incision to perform a circular vitrectorhexis to avoid excessive manipulation of the unstable lens followed by gentle cortex aspiration. A foldable IOL is injected into the sulcus (3‐piece IOL) or bag (1‐piece IOL) if the capsule is sufficiently stable. Through a pars plana incision, the ocutome is then used to perform a posterior capsulotomy to prevent late posterior capsule opacification. In our patient, sulcus IOL placement was more stable than in‐the‐bag placement. Financial Disclosure: Neither author has a financial or proprietary interest in any material or method mentioned.

A Novel Mutation in FOXC1 in a Lebanese Family with Congenital Heart Disease and Anterior Segment Dysgenesis: Potential Roles for NFATC1 and DPT in the Phenotypic Variations

Congenital heart diseases (CHDs) are still the leading cause of death in neonates. Anterior segment dysgenesis is a broad clinical phenotype that affects the normal development of the eye, leading in most of the cases to glaucoma which is still a major cause of blindness for children and adolescents. Despite tremendous insights gained from genetic studies, a clear genotype–phenotype correlation is still difficult to draw. In Lebanon, a small country with still a high rate of consanguineous marriages, there are little data on the epidemiology of glaucoma amongst children with or without CHD. We carried out whole exome sequencing (WES) on a family with anterior segment dysgenesis, and CHD composed of three affected children with glaucoma, two of them with structural cardiac defects and three healthy siblings. The results unravel a novel mutation in FOXC1 (p. R127H) segregating with the phenotype and inherited from the mother, who did not develop glaucoma. We propose a digenic model for glaucoma in this family by combining the FOXC1 variant with a missense variant inherited from the father in the dermatopontin (DPT) gene. We also unravel a novel NFATC1 missense mutation predicted to be deleterious and present only in the patient with a severe ocular and cardiac phenotype. This is the first report on FOXC1 using WES to genetically characterize a family with both ocular and cardiac malformations. Our results support the usage of such technology to have a better genotype–phenotype picture for Mendelian-inherited diseases for which expressivity and penetrance are still not answered.

Ophthalmologic Outcomes of Children Born Premature Without ROP: Correlations With Gestational Age and Psychomotor Development

PURPOSE To study ophthalmological outcomes of premature children with no retinopathy of prematurity (ROP) and correlate with neurodevelopmental outcomes. METHODS A total of 69 former preterm infants were evaluated at 2 to 7 years of age. Detailed ophthalmologic examinations were performed. Neurodevelopment was assessed using the Peabody Developmental Motor Scale and Wechsler Preschool and Primary Scale of Intelligence. Another 69 healthy children served as controls. RESULTS The 69 preterm children (38 of 69 boys) and 69 controls (38 of 69 boys) had a mean age of 4.9 ± 1.5 and 4.9 ± 1.4 years, respectively. Compared to controls, preterm infants had vision impairment of 19% versus 1.4% (P = .001), hyperopia of 87% versus 98.5% (P = .21), myopia of 11% versus 1.4% (P = .017), and astigmatism of 39% versus 30.4% (P = .37). Children with any motor disability tended to have worse vision. CONCLUSIONS In the absence of ROP, hyperopia was more common in infants 32 weeks or older who weighed more than 1,500 g at birth; other vision problems were similar in subgroups. This may represent impending myopia in those younger than 32 weeks weighing less than 1,500 g. [J Pediatr Ophthalmol Strabismus. 2017;54(1):32-38.].

Indocyanine Green-Enhanced Thermotherapy for Retinoblastoma

Purpose: To report the outcome of pediatric patients with retinoblastoma refractory to traditional local therapy who were treated with indocyanine green (ICG)-enhanced thermotherapy. Materials and Methods: This is a retrospective review of a case series of 3 patients with bilateral retinoblastoma who were treated with ICG-enhanced thermotherapy after showing no response to conventional chemothermotherapy or transpupillary thermotherapy (TTT) alone noted on two consecutive examinations under anesthesia. Results: The 3 patients had had one eye enucleated previously due to advanced disease, and the remaining eye was diagnosed with a large tumor, which showed either a marginal or no response to systemic chemotherapy and TTT. Addition of ICG enhancement during the subsequent TTT session shrunk the tumor to a measurable size that could then be followed by TTT alone as a means of treatment. One patient had tumor recurrence, at which time additional TTT without ICG was successfully applied after the tumor size had decreased; ICG enhancement was then added whenever TTT alone provided no response. Conclusions: ICG enhancement with TTT led to a measurable tumor regression in lesions that had previously not been responsive to traditional chemothermotherapy or isolated TTT. Message: These tumors had shown a minimal to no response to previous TTT treatment. However, adding ICG resulted in a measurable regression even though the same TTT treatment parameters were applied.

Is Inferior Oblique Overaction Associated With Astigmatism

PURPOSE To study the relationship between inferior oblique muscle overaction and astigmatism, and to explore any change in astigmatism after surgery. METHODS This was a retrospective chart review of patients undergoing strabismus surgery. Demographic data collected included age, diagnosis, preoperative refraction, presence of inferior oblique overaction, surgery performed, and postoperative refraction. Patients were divided into three groups: those having only horizontal strabismus without inferior oblique overaction (no inferior oblique group) as a control group, those having bilateral inferior oblique overaction (bilateral inferior oblique group), and those having unilateral inferior oblique overaction (unilateral inferior oblique group). Right eyes of the bilateral inferior oblique and no inferior oblique groups were chosen for analysis, whereas the eye with inferior oblique overaction was included in the unilateral cases. Refractions were converted to power vector coordinates for comparison. Statistical analysis was performed to compare the power vectors among groups using the no inferior oblique group as controls and to explore any postoperative change in astigmatism. RESULTS One hundred eighteen patients undergoing strabismus surgery were included (60 males and 58 females; mean age: 11.31 ± 10.59 years). Patients were divided into three groups: those having only horizontal strabismus without inferior oblique overaction (no inferior oblique group; 60 patients) as controls, those having bilateral inferior oblique overaction (bilateral inferior oblique group; 41 patients), and those having unilateral inferior oblique overaction (unilateral inferior oblique group; 17 patients). Preoperatively, there were no differences in astigmatism when comparing eyes with and without inferior oblique overaction. Postoperatively, both the no inferior oblique group and the bilateral inferior oblique group equally showed an increase in with-the-rule cylinder power (P = .02 and .01, respectively). CONCLUSIONS Inferior oblique muscle overaction did not result in an increased prevalence of astigmatism along the axis of the overacting muscle.