ABSTRACT
Background Pseudoexfoliation syndrome (PEX) is often complicated with cataract,accompanied by zonular defects.Zonular related complications easily happened intraoperatively and postoperatively.It is very important to choose the operating timing and method to reduce the complications and improve curative effects.However,relative study is rare.Objective This study was to analyze the curative effects of cataract extraction and intraocular lens (IOL) implantation for PEX combined cataract (PEXC) with zonular defect and discuss the appropriate operation timing and method.Methods A serial cases-observational study was performed,and written informed consent was obtained from each patient prior to ocular surgery.Twenty-three eyes of 21 patients with PEXC and zonular defect were included and received PEXC surgery in Second People's Hospital of Kashi from July 2012 to December 2015.The patients were divided into phacodonesis type (18 eyes) and subluxation of lens (5 eyes) based on the severity of zonular defect and grade Ⅱ (4 eyes),grade Ⅲ (9 eyes),grade Ⅳ (7 eyes) and grade Ⅴ (3 eyes) nuclei based on the hardness of lens nuclei.Phacoemulsification combined capsular tension ring (CTR) or modified CTR (MCTR) insertion and IOL implantation was carried out for grade Ⅱ and Ⅲ nuclei with phacodonesis eyes.or extracapsular cataract extraction combined CTR and IOL implantation was carried out for grade Ⅳ and Ⅴ nuclei with phacodonesis eyes,and phacoemulsification combined MCTR insertion and IOL implantation,or lens loop nucleusdeliver,anterior vitrectomy combined suspensory IOL implantation were performed for subluxation eyes.The patients were followed up for consecutive 3 months,and optimal operation timing,best corrected visual acuity (BCVA),intraocular pressure (IOP),complications and anterior capsular opening,IOL position were assessed.Results In the patients with phacodonesis,CTR was inserted in 10 eyes,and MCTR was inserted in 3 eyes,and extracapsular cataract extraction combined CTR and IOL implantation was carried out in 4 eyes and l eye received anterior vitrectomy combined suspensory IOL implantation.In the patient with subluxation of lens,only 1 eye finished successful phacoemulsification combined anterior vitrectomy and suspensory IOL implantation,and other 4 eyes received lens loop nucleus-deliver,anterior vitrectomy combined suspensory IOL implantation.The BCVA of the operated eyes was ＞0.5 in 4 eyes,＞0.3-≤0.5 in 6 eyes,＞0.1-≤0.3 in 8 eyes,≤0.1 in 5 eyes,which was better than that before surgery (X2 =17.29,P＜0.01).The IOP was (16.82 ±2.25) mmHg before surgery and reached (16.12±2.67) mmHg 3 months after surgery,with a significant difference between them (t=0.108,P＞0.05).The intra-and post-operative complications included small pupil,corneal edema,residual cortex and posterior capsular opacification.Conclusions The operative process of PEXC eyes with zonular defect is complex.The choice of operative time and methods depends upon the type of zonular defect,hardness of lens nuleus,with or without subluxation of lens.A carefully ocular examination before operation is crucial for the therapy of PEXC.
ABSTRACT
Background Congenital cataract is a major cause for blindness of childhood.Genetic gene mutation accounts for almost 1/3 of congenital cataract patients.The most common inheritance type is autosomal dominant congenital cataract (ADCC).Over 100 mutations in 26 genes have been found to be associated with ADCC.Objective This study was to identify the disease-causing gene mutation in a family with ADCC.Methods This study was approved by Ethic Committee of Beijing Tongren Hospital and followed Declaration of Helsinki.A northern Chinese family with autosomal dominant congenital nuclear cataract was entrolled in Beijing Tongren Hospital in January 2011.Ocular examinations were performed and periphery blood specimens were collected from each family member under the informed consent.Genomic DNA was extracted.Twenty-one microsatellite markers around 17 ADCC genes were selected for linkage analysis,and two-point LOD score was calculated.CRYGC gene and CRYGD gene were amplified and screened for mutations using direct sequencing.ProtScale software was used to analyze the changes of hydrophobicity of the mutated protein.Co-segregation of the observed change with the disease phenotype was further detected by restriction fragment length polymorphism (RFLP).Results This family included 20 members of 4 generations,and 9 patients were examined in serial 4 passages,which conformed to autosomal dominant inheritance pattern.Clinical examination revealed binocular congenital nuclear cataract in the 9 patients.Maximum two-point LOD score was 4.68 at marker D2S325 (θ=0).A known T→C change at position 127 of cDNA sequence was found by mutations screening of CRYGD gene.ProtScale programs showed an obvious increase of the local hydrophobicity in the mutant protein.RFLP results indicated that this missense mutation co-segregated with affected members of the family,but was absent in unaffected members and 100 unrelated controls.Conclusions c.T127C mutation of CRYGD gene appears to be the molecular pathogenesis of this ADCC family.Aberrant structure of mutant CRYGD protein caused by hydrophobicity change may lead to opacification of lens.