Inverted Internal Limiting Membrane Flap Technique for Repair of Large Macular Holes: A Short-term Follow-up of Anatomical and Functional Outcomes.

BACKGROUND: Inverted internal limiting membrane (ILM) flap technique has recently been reported in a limited number of studies as an effective surgical technique for the management of large macular holes (MHs) with fair MH closure rates as well as gains in visual acuity. In the current study, longitudinal changes in multi-focal electroretinogram (mfERG) responses, best-corrected visual acuity (BCVA) and spectral-domain optical coherence tomography (SD-OCT) were evaluated in eyes with large MHs managed by this technique. METHODS: A prospective noncontrolled interventional study of eight patients (eight eyes) with large MHs (minimum diameter >400 µm) was conducted. All MHs were treated with pars plana vitrectomy and indocyanine green-assisted inverted ILM flap technique. SD-OCT images were used to assess the anatomical outcomes of surgery while BCVA and mfERG were used to evaluate the functional outcomes during a 3-month follow-up. RESULTS: All patients underwent successful intended manipulation and translocation of the ILM flap without flap dislocation and achieved complete anatomical closure. Partial microstructural reconstruction, demonstrated on SD-OCT as restoration of the external limiting membrane and the ellipsoid zone, was observed in all cases as early as 1 month after surgery. Functionally, as compared to baseline, all patients showed improvements in BCVA and all but one in mfERG response during follow-up. However, Pearson's test revealed no significant correlations between BCVA and mfERG responses of the fovea and of the macular area at each evaluation time point. CONCLUSIONS: Inverted ILM flap technique appears to be a safe and effective approach for the management of large idiopathic MHs with favorable short-term anatomical and functional results. Postoperative reconstruction of the microstructure generally shows good consistency with improvements in both BCVA and mfERG response, of which the latter might be a supplement for the former in postoperative functional follow-up.

[Clinical features of congenital stationary night blindness].

OBJECTIVE: To explore the clinical features of Chinese patients with congenital stationary night blindness (CSNB). METHODS: An observational serial case study was conducted for 22 patients diagnosed as CSNB at Department of Ophthalmology, Peking Union Medical College Hospital from December 2003 through December 2011. Sixteen patients (72.7%) were males and 6 patients (27.3%) were females. Their age range was 4-73 years old. All of them underwent detailed ocular examinations including electroretinogram (ERG). Thirteen patients underwent optical coherence tomography (OCT) while 9 had visual field (VF) testing. Medical and family history was recorded. RESULTS: Seven patients had a positive family history. Thirteen patients (59.1%) complained of a poor night vision. Best corrected visual acuity was < 0.8 in both eyes for 16 patients (72.7%). There were nystagmus (n = 4) and strabismus (n = 4). Except for 1 complicated with background diabetic retinopathy, all other patients showed normal or myopic fundi. Nine patients revealed peripheral visual field defects. Twenty-one (95.5%) patients had Schubert-Bornstein type negative ERG while another one had Riggs type ERG. Among 21 Schubert-Bornstein type patients, 13 (61.9%) patients showed complete type CSNB and 8 (38.1%) were of incomplete CSNB. Before referral to our tertiary hospital, only 2 patients were suspected as CSNB. The common primary diagnoses included pathogenic myopia, amblyopia and retinitis pigmentosa. CONCLUSION: CSNB is frequently misdiagnosed in China. Poor visual acuity is one of the major complaints. And around 50% CSNB patients experience night vision problem. Complete CSNB is more common than incomplete type in China.

[Progress in the studies of molecular genetics in Bietti crystalline corneoretinal dystrophy].

CYP4V2, a relatively new member of human cytochrome P450 (P450) enzymes, is termed an "orphan" P450 because its substrate specificity and physiological roles are unknown. Mutations in the CYP4V2 gene is associated with an autosomal recessive inherited ocular disease named Bietti's crystalline dystrophy (BCD). The strong gene-disease associations provide unique opportunities for elucidating the substrate specificity of this orphan P450s and unraveling the biochemical pathways that may be impacted in patients with CYP4V2 functional deficits.

Idiopathic phacodonesis in senile cataract patients in Qinghai, China.

AIM: To investigate the frequency of idiopathic phacodonesis (IP) in senile cataract subjects and the short-term clinical outcomes following cataract surgery. METHODS: This institutional case-control study included 1301 consecutive low-income cataract subjects from June to November 2009. Anterior segment were carefully evaluated with dilated pupil under slit-lamp. IP were screened and graded by a criteria set by the authors. Risk factors, surgical outcomes, and operative complications were analyzed. RESULTS: A total of 42 subjects (3.2%) with IP were diagnosed and classified as grade 1 (36 subjects), grade 2 (5 subjects) and grade 3 (1 subject). Harder lenses and intumescent cataracts were observed in the IP group than the control group (P<0.05). Logistics regression test also indicated the main risk factor was the hardness of the lens. The incidence of zonular dialysis during surgery was 23.8% (10 eyes), which was significantly higher than the controls (0.7%, P<0.001). Visual outcomes of the two groups were not statistically or clinically significant. CONCLUSION: Hard nucleus and intumescent cataract are related to IP in senile cataract subjects in Qinghai, China. With more care being taken, grade 1 and some of the grade 2 IP subjects achieved similar surgical outcomes as compared to controls.

[Analysis of optical coherence tomography in early stage of optic neuritis in multiple sclerosis patients].

OBJECTIVE: To detect the changes in the retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) in the eyes of multiple sclerosis patients during the early stage of optic neuritis. METHODS: A prospective case series study. Suspected acute optic neuritis of multiple sclerosis (MS) patients who attended the department of ophthalmology in Peking Union Medical College hospital from Feb. 2007 to Nov. 2010 were collected. Twenty two MS patients were evaluated within the first week of the attack of acute optic neuritis. The average thickness of RNFL and GCC was measured and a three dimensional image of optic disk was reconstructed using optical coherence tomography (OCT). RESULTS: Within the first week of onset, the average thickness of RNFL and GCC of first attack eyes increased 75% and 64%, respectively. The average thickness of RNFL and GCC in relapsed eyes decreased 91.7% and 62.5% respectively. The average thickness of RNFL and GCC of the fellow eyes also increased 60% and 43% respectively, within the first week of onset. More cases of optic disk edema and thickening of RNFL were found by OCT than by direct ophthalmoscopy. CONCLUSIONS: Different changes of the thickness of RNFL and GCC and morphology of the optic disk were detected during the early stage of the initial attack or relapsed optic neuritis in MS patients. OCT could detect such differences.

[The development in the studies of AAV-mediated gene therapy in retina].

Significant progress in understanding the molecular basis of retinal disorders has led to the development of gene therapies for treatment of these diseases. Adeno-associated virus (AAV) is a useful vector for the treatment of retinal diseases due to its low toxicity and immunogenicity, ability to transducer both dividing and non-dividing cells, and stable transgene expression. A variety of animal studies and clinical trials have proved the safety and effectivity of retinal AAV-mediated gene therapy. AAV-mediated gene therapy, such as anti-angiogenic proteins, neurotrophic factors, anti-apoptosis factors were studied in animal disease models, and the results were satisfactory. However, the main drawback of AAV vectors is its relatively small packaging capacity, which needs further improvement.

R555W mutation of TGFbetaI related to granular corneal dystrophy in Chinese patients.

BACKGROUND: Mutations in the transforming growth factor beta I (TGFBI) gene cause several types of autosomal-dominant corneal dystrophies. We investigated the role of this gene in a Chinese family affected by granular corneal dystrophy (GCD). METHODS: Family history and phenotypic data were recorded. The diagnosis of GCD was made on the basis of clinical evaluation. The genomic DNA was extracted from peripheral blood leukocytes. All the exons and flanking intron-exon boundary sequences of TGFbetaI were amplified by polymerase chain reaction (PCR) and screened for mutation by direct DNA sequencing. RESULTS: A heterozygous C to T transition at nucleotide c.1663 (CGG to TGG R555W) of TGFbetaI gene was present in two affected members but was absent in the rest of the family members. CONCLUSION: A recurrent pathogenic R555W of TGFbetaI gene mutation is identified, which appears to be the predominant mutations causing GCD in different populations.

[To reinforce the collection and usage of the genetic resource of glaucoma in China].

Positive family history is one of the risk factors of glaucoma. It indicates that gene defect may play an important role in the development of glaucoma. The advancement of genetic research provides more strategies to understand the genetic mechanism of glaucoma. The precondition of understanding and studying the genetic factors is the possession of enough genetic resource related to diseases. Based on the usage of glaucomatous genetic resources, several genes and loci related to primary glaucoma were determined abroad. Although we hold the richest human genetic resources of diseases in China, there exist some problems in the collection, storage and usage of the genetic resources of diseases, including the lack of the strict guideline in practice, the lack of the active participant from the clinician, not closely work together of the researchers and clinician, in-sufficiently use of the genetic resources, loss of the genetic resources. We should envisage these problems. At present, it is urgent to rationally and use the genetic resource in China.

[Congenital stationary night blindness].

Congenital stationary night blindness (CSNB) is a group of genetically heterogeneous retinopathy with characterized clinical and visual electrophysiological abnormality. Five candidate genes associated with the disease have been identified. Clinical, electrophysiological and molecular genetics about CSNB are reviewed in this paper.

[Study on a rat model of filtering bleb scarring formation].

OBJECTIVE: To investigate a rat animal model of filtering bleb scarring formation. METHODS: Thirty-five of Sprague-Dawley (SD) rats were used in this experiment. The filtration surgery was performed on one eye of each rat and the other eye served as control. The presence of postoperative bleb and clinical manifestation was evaluated. Each group of three rats were sacrificed and the eyes enucleated on day 1, 3, 7, 14, and 28. After the eyes were fixed by 10% formalin, serial paraffin sections of three eyes were labeled with HE staining and the pathological morphology was observed under a microscope. RESULTS: A conjunctival bleb was successfully formed in 35 rats lasting from 8 to 21 days after surgery. An obvious dilatation of blood vessels, infiltration of a great number of neutrophil, and a severe edema of the subconjunctival tissue were observed on day 1 and the above morphological changes plus increased infiltration of macrophages were found on day 3. The dilated blood vessels were lessened while the proliferation of fibroblast was presented with abundant endochylema in oval-shaped nucleus of fibroblasts, which were closely associated with the deposition of small amount of new loose collagen fibers on day 7. The collagen fibers became tight on day 14 and subsequently, the early scar was formed on day 28. CONCLUSION: The rat model of filtering bleb scarring formation may be useful for the investigation of preventing and treating conjunctival scarring resulted from glaucoma filtration surgery and other related eye diseases in the future.

[Novel mutation of fibrillin 1 gene cause ectopia lentis in a Chinese family].

OBJECTIVE: To identify the mutation gene of a Chinese family with ectopia lentis. METHODS: Clinical observation and pedigree analysis were undertaken in a family with ectopia lentis. Venous blood was drawn from 7 affected and 3 unaffected subjects. Genomic DNA was extracted. Linkage to the fibrillin 1 (FBN1) locus was not excluded. Mutation of this gene was screened by PCR of FBN1 exons and direct sequencing. PCR and restrictive endonuclease digestion were applied for population study. RESULTS: A missense mutation G640A in exon six of FBN1 gene was identified in affected patients of this Chinese family. The correspond amino acid change was Gly214Ser. Restrictive endonuclease site Eag I was eliminated. This mutation was not found in unaffected family members of this family nor it was found among 50 unrelated normal controls. CONCLUSIONS: A novel mutation of FBN1 gene with Glycine to Serine change is responsible for the ectopia lentis patients in a Chinese family.

[Eighteen years activity in prevention of blindness in the district of Shunyi, Beijing].

OBJECTIVE: To investigate how the urban tertiary hospital and medical research unit cooperate with rural basic medical unit in creating the model zone in prevention of blindness. METHODS: Peking Union Medical College Hospital (PUMCH) and Shunyi District Bureau of Public Health exerted their advantages to persist and popularize the program for prevention of blindness. A collaborative program in prevention of blindness was conducted by PUMCH and Shunyi District Bureau of Public Health. The targeted subjects were the population in Shunyi District of Beijing. An epidemiological survey of eye diseases was performed in 1984. A program for prevention of blindness was established and conducted afterward. RESULTS: The status of blindness in Shunyi District was unveiled by the eye epidemiological survey of eye diseases in 1984. Three-level primary eye care network and referring and treatment system for cataract blindness was established since 1987. The survey showed that the priority in prevent of blindness is surgical treatment of cataract in the area. The evaluation of the program in prevention and treatment for blindness in 1996 showed that the prevalence of blindness was decreased even it is increasing in both the total population and aged people. CONCLUSION: The cooperation in urban tertiary hospital, medical research unit and basic health care unit, and combination in research and medical practice in prevention of blindness can promote development in the prevention of blindness and possible reverse the tendency of blindness increase.