Xinhua Huang

Quantitative analysis of rhegmatogenous retinal detachment associated with choroidal detachment in Chinese using UBM.

Purpose: To investigate the characteristics of rhegmatogenous retinal detachment associated with choroidal detachment (RRDCD) in a Chinese population by using ultrasound biomicroscope (UBM). Methods: A random prospective study was used to assess 1,389 patients (1,408 eyes) with rhegmatogenous retinal detachment. Comprehensive standardized ophthalmic examinations included intraocular pressure (IOP) by Goldmann applanation tonometer and the entire ocular fundus by Goldmann three-mirror lens, B-type ultrasound, and UBM. Results: A total of 1,389 patients with rhegmatogenous retinal detachment participated in the study, including 906 men and 483 women. Two hundred and sixty-three eyes (18.79%) had RRDCD and the age of patients ranged from 9 to 82 years (median, 50.8 ± 17.7 years). Patients with high myopia (−6.00 diopters or more) represented 31.94% and more frequently experienced low intraocular pressure and multiple retinal breaks. In 263 RRDCD eyes, the results of UBM showed that ranges of choroidal detachment (CD) were <1 quadrant in 9 (3.42%) eyes, from 1 to 2 quadrants in 37 (14.07%) eyes, from 2 to 3 quadrants in 13 (4.94%) eyes, and from 3 to 4 quadrants in 204 (77.57%) eyes. ultrasound biomicroscope also showed that the angular ranges of CD were between 3.31° and 45.65° (mean, 15.98 ± 9.29°). In addition, UBM showed the mean values of CD angle for the superior (15.42 ± 9.40°), nasal (14.08 ± 8.66°), inferior (15.03 ± 9.05°), and temporal (15.96 ± 9.22°) sides. No statistically significant differences were found among any of these comparisons (F value = 2.011, P > 0.05). Conclusion: Retinal detachment associated with CD occurs more frequently in older people or in patients with high myopia, who usually present with low intraocular pressure and multiple retinal breaks. UBM examination can reduce false-negative rate of RRDCD, determine CD degree quantitatively, and guide classification and treatment. UBM combined with B ultrasound testing can provide a precise diagnosis of rhegmatogenous retinal detachment degree and may have important clinical significance for preoperative diagnosis of anterior proliferative vitreoretinopathy and determining operative strategy and postoperative prognosis.

Two novel mutations in the bestrophin-1 gene and associated clinical observations in patients with best vitelliform macular dystrophy

The purpose of the current study was to investigate the 11 bestrophin-1 (BEST1) exons in patients with best vitelliform macular dystrophy (BVMD), and to characterize the associated clinical features. Complete ophthalmic examinations were conducted on two families, and two family members were diagnosed with BVMD. Genomic DNA was extracted from the leukocytes of peripheral blood collected from the patients and their family members, in addition to 100 unrelated control subjects recruited from the same population. The polymerase chain reaction was used to amplify a total of 11 exons of the BEST1 gene, which were directly sequenced. Ophthalmic examinations, including best-corrected visual acuity, slit-lamp examination, fundus examination, fundus photography and fluorescein angiography imaging, as well as anterior segment analysis with Pentacam and optical coherence tomography, were conducted. The patients exhibited yellowish lesions in the macular area. A heterozygous mutation c.910_912delGAT (p.304del Asp) in exon 7 was identified in Case 1. A heterozygous BEST1 missense mutation c.685T>G (p.Trp229Gly) in exon 5 was identified in Case 2, but not in any of the unaffected family members or normal controls. Although BEST1 gene mutations and polymorphisms have previously been reported in various ethnic groups, the current study identified, for the first time to the best of our knowledge, two novel BEST1 gene mutations in patients with BVMD.

C278F mutation in FGFR2 gene causes two different types of syndromic craniosynostosis in two Chinese patients

The current study was performed with aim to investigate the fibroblast growth factor receptor 2 (FGFR2) gene in two Chinese families with two different forms of syndromic craniosynostosis, and to characterize their associated clinical features. Two families underwent complete ophthalmic examinations, and two patients from each family were diagnosed with craniosynostosis. Genomic DNA was extracted from leukocytes of peripheral blood collected from these two families and from 200 unrelated subjects within the same population as controls. Exons 8 and 10 of the FGFR2 gene were amplified by polymerase chain reaction and directly sequenced. Ophthalmic examinations of the two patients revealed shallow orbits and ocular proptosis, accompanied by midface hypoplasia and craniosynostosis. Case 1 had retinal detachment, abnormal limbs and hands, while case 2 exhibited normal hands and feet upon clinical examination. A heterozygous FGFR2 missense mutation c.833G>T (C278F) in exon 8 was identified in these two patients, but not in unaffected family members or the normal controls. Although FGFR2 gene mutations and polymorphisms have been studied in various ethnic groups, we report a mutation of FGFR2 in two different Chinese patients with two different types of syndromic craniosynostosis.

Two heterozygous mutations identified in one Chinese patient with bilateral macular coloboma

Congenital macular coloboma is characterized by defined punched out atrophic lesions of the macula. The present study aimed to investigate the genetic alterations of one Chinese sporadic patient with bilateral large macular coloboma. Complete ophthalmic examinations, including best-corrected visual acuity, slit-lamp examination, fundus examination, fundus photograph and fundus fluorescein angiography imaging, Pentacam, and optical coherence tomography were performed on the patient. Genomic DNA was extracted from leukocytes in a peripheral blood sample collected from the patient, the patients unaffected family members and from 200 unrelated control subjects from the same population. Next-generation sequencing of the known genes involved in ocular disease was performed. The functional effects of the mutation were analyzed using Polymorphism Phenotyping (PolyPhen) and Sorting Intolerant From Tolerant (SIFT). One heterozygous bestrophin 1 (BEST1) mutation c.1037C>A (p.Pro346His, p.P346H) in exon 9 and one heterozygous regulating synaptic membrane exocytosis 1 (RIMS1) mutation c.3481A>G (p.Arg1161Gly, p.R1161G) in exon 23 were identified in the patient being investigated, but not in the unaffected family members or unrelated control subjects. Polyphen and SIFT predicted that the amino acid substitution p.P346H in the BEST1 protein is damaging. In addition, Polyphen predicted that the amino acid substitution p.R1161G in the RIM1 protein is damaging. The results of the current study have increased the mutation spectrums of BEST1 and RIMS1, and are valuable for improving the current genetic counseling process and developing novel therapeutic interventions for patients with macular coloboma.

Observation of Persistent Fundus Fluorescence after Internal Limiting Membrane Peeling Assisted by Indocyanine Green Solution of Different Concentrations

PURPOSE To investigate how long indocyanine green (ICG) remains in the fundus after vitreoretinal surgery assisted with ICG, and to identify factors that influence the persistence duration. METHODS Fifty five eyes diagnosed as idiopathic macular hole (Stage 2 and 3) were randomly divided into five groups. ICG solution at concentrations of 5, 2.5, 2.5, 1.25, and 0.5 mg/ml, employed in cases of Group I to V respectively, was applied to stain the internal limiting membrane (ILM) during the procedure of internal limiting membrane peeling. A prospective study was carried out after pars plana vitrectomy and ILM peeling were performed on 55 eyes with Stage 2, 3, or 4 idiopathic macular holes. Infrared fundus pictures were obtained in all patients before and after surgery. RESULTS High levels of fluorescence from residual ICG (ICG hyperfluorescence) were mainly localized at the posterior pole of the fundus after surgery. In Group Ⅰ, Ⅱ, III, IV and V, the duration of persistence of flurorescence from ICG was 8.33±0.87, 3.59±0.94, 3.75±0.79, 2.30±0.48, and 1.29±0.49 months, respectively. Although no significant difference was detected between Group Ⅱ and Group III, the general inter-group difference was significant among the five groups in which different ICG concentration was applied. In Group III, even though 90% of the macular holes acquired anatomical closure, ICG hyperfluorescence was detected in the macular area. CONCLUSION ICG remains in the fundus for a period of months. The persistence duration of fluorescence from ICG is positively correlated with the concentration and the staining time of ICG. Hyaluronan is beneficial in reducing the amount of ICG residue in the macular area.

Two Paired Box 6 mutations identified in Chinese patients with classic congenital aniridia and cataract

Congenital aniridia is a rare genetic disorder characterized by a variable degree of hypoplasia or absence of iris. It is frequently associated with keratopathy, cataract, juvenile-onset glaucoma and foveal and optic nerve hypoplasia. Mutations in the Paired Box 6 (PAX6) gene on chromosome 11p13 have been demonstrated to cause aniridia. The aim of the present study was to investigate the genetic variations of PAX6 in two sporadic patients from southern China with classic congenital aniridia and cataract. Complete ophthalmic and physical examinations were performed, including best-corrected visual acuity, intraocular pressure, slit-lamp examination, fundus examination, optical coherence tomography, ultrasound biomicroscopy, and Pentacam scanning. Genomic DNA was extracted from leukocytes of peripheral blood collected from the two patients, their unaffected parents and 200 unrelated control subjects from the same population. Exons 4–13 of the PAX6 gene were amplified by polymerase chain reaction and sequenced directly. Patient 1 was affected with aniridia accompanied by congenital cataract and nystagmus. A novel heterozygous PAX6 frameshift mutation c.277delG (p.Glu93SerfsX31) in exon 6 was identified in this patient. Patient 2 was presented with aniridia, congenital cataract, lens subluxation and glaucoma. A recurrent nonsense mutation c.718C>T (p.Arg240X) in exon 9 was identified in this patient. The present results expand the mutation spectrum of PAX6 and will be valuable for genetic counseling in the affected families. Additionally, the identification of these mutations reiterates the importance of PAX6 in ocular development and sheds light on the pathogenesis of congenital aniridia.

Targeted next‑generation sequencing identifies two novel COL2A1 gene mutations in Stickler syndrome with bilateral retinal detachment

Stickler syndrome is a group of inherited connective tissue disorders characterized by distinctive facial and ocular abnormalities, hearing loss and early-onset arthritis. The aim of the present study was to investigate the genetic changes in two Chinese patients with Stickler syndrome, manifested as bilateral retinal detachment and peripheral retinal degeneration. Complete ophthalmic examinations, including best-corrected visual acuity, slit-lamp examination and fundus examination, were performed. Genomic DNA was extracted from leukocytes of the peripheral blood collected from the patients, their unaffected family members and 200 unrelated control subjects from the same population. Next-generation sequencing of established genes associated with ocular disease was performed. A heterozygous collagen type II α1 chain (COL2A1) mutation c.1310G>C (p.R437P) in exon 21 was identified in Family 1 and a heterozygous COL2A1 mutation c.2302-1G>A in intron 34 was identified in Family 2. The functional effects of the mutations were assessed by polymorphism phenotyping (PolyPhen) and sorting intolerant from tolerant (SIFT) analysis. The c.1310G>C mutation was predicted to damage protein structure and function, and the c.2302-1G>A mutation was predicted to result in a splicing defect. The findings of the current study expand the established mutation spectrum of COL2A1, and may facilitate genetic counseling and development of therapeutic strategies for patients with Stickler syndrome.

Bestrophin 1 gene analysis and associated clinical findings in a Chinese patient with Best vitelliform macular dystrophy

The aim of the present study was to investigate the clinical characteristics and the underlying genetic causes of Best vitelliform macular dystrophy (BVMD) in a sporadic case in a Chinese patient. A 10-year-old boy was diagnosed with BVMD; complete ophthalmic examinations were performed, including best-corrected visual acuity, intraocular pressure, slit-lamp examination, fundus photograph, optical coherence tomography and fundus fluorescein angiography imaging. Genomic DNA was extracted from leukocytes of the peripheral blood collected from this patient and his family members. DNA samples from 200 unrelated subjects from the Chinese population were used as controls. A total of 11 exons of the bestrophin 1 (BEST1) gene were amplified by polymerase chain reaction and directly sequenced. The results revealed that the patient presented with yellowish lesions in the macular area. Heterozygous mutations c.292G>A (p.Glu98Lys) in exon 4 and c.1608C>T (p.Thr536Thr) in exon 10 of the BEST1 gene were identified in this sporadic case; however, this was not identified in any of his unaffected family members or in the normal controls. The c.292G>A (p.Glu98Lys) mutation has not been previously reported, whereas the c.1608C>T (p.Thr536Thr) mutation is a previously characterized single nucleotide polymorphism (SNP). In conclusion, BEST1 gene mutations and polymorphisms have been reported in diverse ethnic groups, and the present study identified a novel BEST1 gene mutation and an SNP that occurred simultaneously in a Chinese patient with BVMD.

FGFR2 mutations and associated clinical observations in two Chinese patients with Crouzon syndrome

The aim of the present study was to identify mutations in the fibroblast growth factor receptor 2 (FGFR2) gene in patients with Crouzon syndrome and characterize the associated clinical features. A total of two Chinese patients diagnosed with Crouzon syndrome underwent complete examinations, including best-corrected visual acuity, slit-lamp, examination, fundus examination, optical coherence tomography and computed tomography of the skull. Genomic DNA was extracted from peripheral blood samples collected from the patients, as well as their family members and 200 unrelated control subjects from the same population. Exons 8 and 10 in the FGFR2 gene were amplified by polymerase chain reaction and directly sequenced. Patient #1 had a heterozygous missense mutation (c.1025G>A, p.C342Y) in exon 10 of FGFR2. Patient #2 had a heterozygous mutation (c.1084+1 G>T; IVS10+1G>T) in intron 10. The mutations were not present in any of the unaffected family members or unrelated control subjects. These findings expand the mutation spectrum of FGFR2, and are valuable for genetic counseling in addition to prenatal diagnosis in patients with Crouzon syndrome.

Genetic variations in Bestrophin‑1 and associated clinical findings in two Chinese patients with juvenile‑onset and adult‑onset best vitelliform macular dystrophy

Best vitelliform macular dystrophy (BVMD) is a hereditary retinal disease characterized by the bilateral accumulation of large egg yolk-like lesions in the sub-retinal and sub-retinal pigment epithelium spaces. Macular degeneration in BVMD can begin in childhood or adulthood. The variation in the age of onset is not clearly understood. The present study characterized the clinical characteristics of two Chinese patients with either juvenile-onset BVMD or adult-onset BVMD and investigated the underlying genetic variations. A 16-year-old male (Patient 1) was diagnosed with juvenile-onset BVMD and a 43-year-old female (Patient 2) was diagnosed with adult-onset BVMD. Comprehensive ophthalmic examinations were performed, including best-corrected visual acuity, intraocular pressure, slit-lamp examination, fundus photography, optical coherence tomography, fundus fluorescein angiography imaging and Espion electrophysiology. Genomic DNA was extracted from peripheral blood leukocytes collected from these patients, their family members, and 200 unrelated subjects within in the same population. The 11 exons of the bestrophin-1 (BEST1) gene were amplified by polymerase chain reaction and directly sequenced. Both patients presented lesions in the macular area. In Patient 1, a heterozygous mutation c.903T>G (p.D301E) in exon 8 of the BEST1 gene was identified. This mutation was not present in any of the unaffected family members or the normal controls. Polymorphism phenotyping and the sorting intolerant from tolerant algorithm predicted that the amino acid substitution D301E in bestrophin-1 protein was damaging. In Patient 2, a single nucleotide polymorphism c.1608C>T (p.T536T) in exon 10 of the BEST1 gene was identified. These findings expand the spectrum of BEST1 genetic variation and will be valuable for genetic counseling and the development of therapeutic interventions for patients with BVMD.