1.Clinical analysis of functional optical zone after transepithelial photorefractive keratectomy in patients with different degrees of myopic astigmatism
International Eye Science 2023;23(9):1466-1470
AIM: To evaluate the effect of preoperative degrees of myopic astigmatism and anterior corneal curvature on the functional optical zone(FOZ)after transepithelial photorefractive keratectomy(TransPRK).METHODS: Retrospective study was conducted on 78 patients(130 eyes)with myopia and myopic astigmatism who underwent TransPRK, and they were divided into control group(cylinder 0D), moderate astigmatism group(-0.50~-2.00D)and high astigmatism group(>-2.00~<-6.00D). The FOZ was measured and compared among the three groups 6mo after operation. The correlations between attempted correction, anterior corneal curvature, corneal aberrations, Q value, and the FOZ were analyzed.RESULTS: At 6mo after operation, the mean FOZ was 5.16±0.12mm in the control group, 5.29±0.23mm in the moderate astigmatism group, and 5.49±0.23mm in the high astigmatism group(P<0.001), and the FOZ of the high astigmatism group was significantly higher than moderate astigmatism and control group(P<0.05, P<0.001); Pearson correlation analysis showed that the changes in spherical equivalent, total corneal higher-order aberrations(HOAs), coma, and spherical aberration were all negatively correlated with FOZ(all P<0.05); and FOZ positively correlated with changes in the steep curvature(K2), mean curvature(Km), corneal astigmatism, and Q value(all P<0.01). Multiple linear regression analysis showed that there was still positive correlation between preoperative K2 and FOZ after adjusting for other risk factors(P<0.001).CONCLUSION: Patients with high astigmatism can obtain a larger FOZ and less induced coma after TransPRK. A larger FOZ can be achieved in eyes with steeper keratometry.
2.New progresses of micro invasive glaucoma surgery
International Eye Science 2019;19(6):945-949
The Micro-invasive glaucoma surgery(MIGS)group of operations has been developed in the recent years to reduce some of complications of most standard glaucoma procedures such as trabculectomy. In order to increase the surgical effect, a new group of surgical manners has emerged that seeks to decrease IOP with lower associated rates of complications. The MIGS of the latest technique and devices are presented by three manners of reducing IOP: aqueous reduction surgery(Endoscopic Cyclophotocoagulation, Ultrasound Cyclo-Plasty); external filtering surgery(Implantation of EX-PRESS miniature glaucoma device, CANALOPLASTY); internal filtering surgery(Trabecular microbypass stent, Ab Interno Trabeculectomy). The article will summarize clinically relevant information of the glaucoma treatment and to describe indications, advantages and disadvantages of the MIGS.
3.Finite element analysis of the mechanism of dorsiflexion injury of wrist joint in elderly people after falls
Zexin HOU ; Benke XU ; Yuan DAI ; Chuan HE ; Chaoju ZHANG ; Xiaolin LI
Chinese Journal of Tissue Engineering Research 2024;28(6):886-890
BACKGROUND:At present,wrist protection products designed in and outside China have not solved the contradiction between protecting the wrist joint from injury and maintaining the flexible movement of the wrist joint. OBJECTIVE:To investigate the biomechanical mechanism of dorsiflexion injury of the wrist joint in elderly people after falls,and to provide a biomechanical basis for the prevention and treatment of wrist injury in elderly people after falls. METHODS:A 65-year-old man was selected to obtain the original data by uninterrupted CT scan of the middle and lower 2/3 of his left forearm up to the end of the finger.A finite element model of wrist dorsiflexion was established using ANSYS 12.0 finite element software.The palm surface of the model was constrained,and the model at a velocity load of 2 m/s in the direction of vertical downward was given to simulate the injury state of the palm when the elderly fall.The stress distribution of the soft tissues and bones of the wrist joint and the change of the stress with time were observed after the load was applied. RESULTS AND CONCLUSION:(1)A realistic and effective finite element model of the dorsal extension position of the wrist joint of the elderly was established.The soft tissue stresses were mainly concentrated in the small fissure of the palm and the dorsal side of the wrist after loading.The skeletal stresses were mainly concentrated in the lower end of the ulnar radius dorsally.The stresses in the lower end of the radius were the greatest.The palmar stresses were mainly concentrated in the middle and lower 1/3 of the radius and the hook bone.The stress distribution of the ulnar radius was asymmetric,and the stresses in the radius were more concentrated.(2)The results of the study are consistent with the clinical situation of a fallen wrist injury in elderly people,and can be used to explain the mechanism of wrist dorsiflexion injury,which can provide the biomechanical basis for the design of wrist protection devices that can be used to prevent wrist injury induced by falling and the treatment of wrist injury in elderly people.
4.Research progress of intravitreal Dexamethasone implant in the treatment of non-infectious uveitic macular edema
International Eye Science 2020;20(2):258-262
Macular edema(ME)is a typical non-specific complication of uveitis, one of the common causes of visual impairment in patients with non-infectious uveitis(NIU). The treatment of uveitis related ME is still challenging in clinic. Various agents, such as corticosteroids, anti-vascular endothelial growth factors, and immune-modulators, have been used for combating uveitis related ME. However, there is not enough evidence to support the efficacy of any of these agents. Intravitreal dexamethasone implant(IDI, Ozurdex©; Allergan Inc, Irvine, CA)is a widely administered corticosteroid for the long-term management of uveitic ME in certain cases. Recent studies have demonstrated that IDI effectively improves uveitis related ME, and this effect could be sustained for at least six months with close monitoring and retreatment, as needed. Currently, we reviewed major clinical studies about IDI in eyes with NIU and briefly overviewed their results.
6.Comparison of subthreshold micropulse laser treatment and PDT in patients with chronic central serous chorioretinopathy
International Eye Science 2019;19(6):1063-1067
AIM: To compare the efficacy and safety of 577nm subthreshold micropulse laser(SML)and photodynamic therapy(PDT)in patients with chronic central serous chorioretinopathy(cCSC).
METHODS: Thirty patients(30 eyes)with cCSC were treated in our hospital from February 2015 to April 2018. And 15 patients(15 eyes)were treated with SML(577 nm)while the others were treated by PDT. The BCVA and CMT as well as complications were observed at 1, 3, 6mo after treatment.
RESULTS: At 1mo after treatment, BCVA was increased to 0.37±0.13 in SML group and 0.20±0.11 in PDT group(t=-3.93, P<0.001); CMT was decreased to 382.80±76.54μm in SML group and 247.60±28.46μm in PDT group(t=-6.41, P<0.001). Although improvements of BCVA and CMT were both achieved in two groups, improvements in PDT group were better than those in SML group. At 3mo and 6mo after treatment, both BCVA and CMT were no significant difference between the two groups(P>0.05). During the follow-up period, there were no obvious complications or recurrence observed.
CONCLUSION: Both SML(577nm)and PDT were effective and safe in the treatment of cCSC, but the theraputic effects of PDT was slightly quicker than SML. Further, with the prolongation of recovery time, the curative effects of these treatments were similar. Additionally, SML(577nm)costs was much cheaper than PDT and had no risk of injury or allergy for patients, and patients with cCSC could also be treated repeatedly using it.
7.Analysis of target cytokines affecting OCTA changes following anti-VEGF treatment in PCV eyes
Qing XU ; Lei QIAO ; Chaoju GONG ; Ruifang FENG ; Yalu LIU ; Yongcheng SUN ; Yipeng ZHANG ; Suyan LI
Chinese Journal of Experimental Ophthalmology 2021;39(7):632-639
Objective:To explore the predictability cytokines in aqueous humor affecting optical coherence tomography angiography (OCTA) parameters after anti-vascular endothelial growth factor (VEGF) treatment in patients with polypoidal choroidal vasculopathy (PCV).Methods:A cross-sectional study was carried out.Twenty eyes of 20 patients with PCV were included in Xuzhou First People's Hospital from July 2017 to July 2020.All PCV eyes were treated by intravitreal injection of conbercept (IVC) following 3+ PRN regimen.One hundred μl of aqueous humor was collected before treatment and before the third injection, respectively.Thirteen kinds of cytokines in the aqueous humor were detected with Luminex bead-based multiplex array.The aqueous humor of 16 eyes of 16 cataract patients with age and gender matched were collected in the same way during phacoemulsification surgery as control.The values of center macular thickness (CMT), subretinal fluid height (SRFH), pigment epithelial detachment height (PEDH) and pigment epithelial detachment diameter (PEDD) of the eyes in the PCV group were examined with OCTA system.The target cytokines in aqueous humor affecting OCTA parameter change values (the difference between before and after treatment) was analyzed.This study protocol was approved by an Medical Ethic Committee of Xuzhou First People's Hospital (No.xyyll[2020]27) and complied with Declaration of Helsinki.Written informed consent was obtained from each patient prior to any medical invention.Results:The concentration of interleukin-8 (IL-8), Leptin, hepatocyte growth factor (HGF), fibroblast growth factor-2 (FGF-2), angiopoietin-2 (Ang-2), endothelin-1 and vascular endothelial growth factor-A (VEGF-A) were significantly higher in aqueous humor of the PCV group before treatment than those in the cataract group (all at P<0.05). After treatment, the concentration of VEGF-A in aqueous humor of the PCV group was significantly lower than that before treatment ( P<0.001). The values of CMT, SRFH, PEDH and PEDD were significantly reduced in comparison with before treatment, showing statistical significances (all at P<0.05). The concentration of VEGF-A in aqueous humor was positively correlated and endothelin-1 in aqueous humor was negatively correlated with the change value of CMT ( r=0.592, -0.485, both at P<0.05). The concentration of IL-8 and HGF were positively correlated with SRFH change value ( r=0.492, 0.466, both at P<0.05). VEGF-A and IL-8 concentraions of aqueous humor before treatment were the risk factor of the change value of CMT and SRFH.Every 1pg/ml increase of baseline VEGF-A, the CMT change value reduced 0.836 μm ( P=0.006), and every 1pg/ml increase of baseline IL-8, the SRFH change value reduced 12.522 μm ( P=0.028). Conclusions:The concentrations of VEGF-A and IL-8 in aqueous humor might predict the CMT and SRFH improvement in PCV eyes after anti-VEGF therapy.