Publications by authors named "Qin-Mei Wang"

73 Publications

The mechanism of bud dehyperhydricity by the method of 'starvation drying combined with AgNO3' in Lycium ruthenicum.

Tree Physiol 2022 Apr 22. Epub 2022 Apr 22.

Key Laboratory of Forest Tree Genetics, Breeding and Cultivation of Liaoning Province, College of Forestry, Shenyang Agricultural University, Shenyang 110866, China.

Micropropagation is very important for rapid clonal propagation and scientific research of woody plants. However, the micropropagated materials usually show hyperhydricity which seriously hinder application of the micropropagation. Lycium ruthenicum is an important species of eco-economic forest. Herein, treatment of 'starvation and drying combined with 30 μM AgNO3' (SDCAg+) removed serious hyperhydricity of L. ruthenicum buds regenerated from its green-inflorescence-explants and then gene expression, metabolites of various phytohormones, chloroplasts, chlorophyll (Chl) and total soluble proteins of the hyperhydric and dehyperhydric leaves were compared and analyzed. The results suggested that the SDCAg+ treatment might remove hyperhydricity of L. ruthenicum through reducing water uptake; increasing water loss; up-regulating the expression of chloroplast-ribosomal-protein genes from nuclear genome; down-regulating the expression of cytoplasmic-ribosomal-protein genes; up-regulating the synthesis of the total soluble proteins; restoring the lamellar structure of chloroplast grana and matrix; improving Chl synthesis and reducing Chl metabolism; increasing expression of light-harvesting Chl protein complex genes and content of Chla and b; up-regulating both Photosynthesis and Starch and sucrose metabolism KEGG pathways; up-regulating abscisic acid (ABA), salicylic acid (SA) and their signaling, down-regulating cytokinin (tZ), Jasmonic acid (JA), Jasmonoyl-L-isoleucine (JA-Ile) and their signaling. Also, the above events interact to form a regulatory network of dehyperhydricity by SDCAg+ treatment. Overall, the study indicated key genes/pathways and physiological/subcellular changes involved in dehyperhydricity and then established a dehyperhydric mechanism model of L. ruthenicum. This not only proposed clues for preventing or removing hyperhydricity but also laid foundations for molecular breeding of L. ruthenicum and other species.
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http://dx.doi.org/10.1093/treephys/tpac047DOI Listing
April 2022

The branch-thorn occurrence of Lycium ruthenicum is associated with leaf DNA hypermethylation in response to soil water content.

Mol Biol Rep 2022 Mar 3;49(3):1925-1934. Epub 2021 Dec 3.

Key Laboratory of Forest Tree Genetics, Breeding and Cultivation of Liaoning Province, College of Forestry, Shenyang Agricultural University, Shenyang, 110866, Liaoning, China.

Background: Lycium ruthenicum is an eco-economic shrub which can exist in two forms, thorny and thornless under varying soil moisture conditions. The aim of this study was to determine if the two forms of L. ruthenicum were influenced by soil water content (SWC) and to test the three-way link among SWC, occurrence of branch-thorn and DNA methylation modification.

Methods And Results: Here, pot experiment was carried out to reveal the influence of SWC on the occurrence of branch-thorn and then paraffin sections, scanning electron microscope and methylation-sensitive amplification polymorphism(MSAP) analysis were used to determine the three-way link among SWC, branch-thorn occurrence and DNA methylation. The results showed that (a) soil drought promoted the development of thorn primordium into branch-thorn and (b) branch-thorn covered axillary bud to protect it against drought and other stresses; (c) the branch-thorn occurrence response to drought was correlated with hypermethylation of CCGG sites and (d) thorny and thornless plants of a clone were distinguished successfully based on the MSAP profiles of their leaves.

Conclusions: Branch-thorns of the L. ruthenicum clone, which occurred in response to drought, covered axillary buds to protect them against drought and other stresses; thorn primordium of the clone did not develop into branch-thorn under the adequate soil moisture condition. The occurrence and absence of the branch-thorns were correlated with the hyper- and hypo-methylation, respectively. We proposed that the branch-thorn plasticity might be an adjustment strategy for the environment, which seems to support the theory of "Use in, waste out".
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http://dx.doi.org/10.1007/s11033-021-07004-6DOI Listing
March 2022

A novel micropropagation of Lycium ruthenicum and epigenetic fidelity assessment of three types of micropropagated plants in vitro and ex vitro.

PLoS One 2021 23;16(2):e0247666. Epub 2021 Feb 23.

Key Laboratory of Forest Tree Genetics, Breeding and Cultivation of Liaoning Province, College of Forestry, Shenyang Agricultural University, Shenyang, Liaoning, China.

Lycium ruthenicum is an excellent eco-economic shrub. Numerous researches have been conducted for the function of its fruits but scarcely focused on the somaclonal variation and DNA methylation. An efficient micropropagation protocol from leaves and stems of L. ruthenicum was developed in this study, in which not only the leaf explants but also the stem explants of L. ruthenicum were dedifferentiated and produced adventitious buds/multiple shoots on one type of medium. Notably, the efficient indirect organogenesis of stem explants was independent of exogenous auxin, which is contrary to the common conclusion that induction and proliferation of calli is dependent on exogenous auxin. We proposed that sucrose supply might be the crucial regulator of stem callus induction and proliferation of L. ruthenicum. Furthermore, results of methylation-sensitive amplified polymorphism (MSAP) showed that DNA methylation somaclonal variation (MSV) of CNG decreased but that of CG increased after acclimatization. Three types of micropropagated plants (from leaf calli, stem calli and axillary buds) were epigenetically diverged more from each other after acclimatization and the ex vitro micropropagated plants should be selected to determine the fidelity. In summary, plants micropropagated from axillary buds and leaves of L. ruthenicum was more fidelity and might be suitable for preservation and propagation of elite germplasm. Also, leaf explants should be used in transformation. Meanwhile, plants from stem calli showed the highest MSV and might be used in somaclonal variation breeding. Moreover, one MSV hotspot was found based on biological replicates. The study not only provided foundations for molecular breeding, somaclonal variation breeding, preservation and propagation of elite germplasm, but also offered clues for further revealing novel mechanisms of both stem-explant dedifferentiation and MSV of L. ruthenicum.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0247666PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7901770PMC
August 2021

A Comprehensive Strategy for Laser Corneal Refractive Surgery during the COVID-19 Epidemic in a Tertiary Teaching Hospital in Wenzhou, China.

J Ophthalmol 2020 15;2020:4835630. Epub 2020 Jul 15.

School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.

The novel coronavirus pneumonia COVID-19 is caused by the novel coronavirus SARS-CoV-2, which is highly contagious, has a long incubation period, and can be detected in patients' tears and conjunctival secretions. In this study, we describe our experience regarding the necessary protective measures that need to be taken during ophthalmic examination and treatment. The authors reviewed the clinical work arrangements during the epidemic situation at the Eye Hospital of Wenzhou Medical University in China and analyzed the prevention and control measures that were applied during the laser corneal refractive surgery process. The comprehensive protection protocol, which was established throughout the entire process, included both horizontal (medical staff-patient, medical staff-medical staff, and patient-patient) and vertical (preoperative, intraoperative, and postoperative transmission assessment) approach and was mainly focused on strengthening the protection against potential aerosol transmission that may occur during intraocular pressure measurements and laser ablation. The described and proposed protocol, along with the further guidelines followed by the medical personnel, proved to be efficacious and contributed significantly to the control of the COVID-19 outbreak and the protection of both the patients and the medical staff.
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http://dx.doi.org/10.1155/2020/4835630DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7366208PMC
July 2020

A novel ophthalmic viscosurgical device-free phakic intraocular lens implantation makes myopic surgery safer.

Eye Vis (Lond) 2020 7;7:18. Epub 2020 Apr 7.

The Eye Hospital of Wenzhou Medical University, 270 Xueyuan West Road, Wenzhou, 325000 Zhejiang P. R. China.

Purpose: To assess the efficacy and safety of a novel ophthalmic viscosurgical device-free (OVD-free) method for posterior chamber phakic intraocular lens (PIOL) implantation in myopic eyes.

Methods: In this retrospective cohort study, the medical records of myopic eyes that underwent PIOL (Implantable Collamer Lens, ICL) implantation for myopia correction at the Eye Hospital of Wenzhou Medical University between May 2015 and March 2017 were reviewed. A total of 49 eyes with complete data that met follow up requirements (2 h, 1 day, 1 week, 3 months postoperatively) were recruited. Based on the surgical techniques used, the eyes were divided into the OVD-free method group and the standard method group. The clinical data, including intraocular pressure (IOP), corrected distance visual acuity (CDVA) and spherical equivalent (SE), at each follow-up were collected for comparison. Endothelial cell loss and complications were also investigated.

Results: Twenty-one eyes received the standard method, and 28 eyes received the OVD-free method. A rise in IOP > 22 mmHg at 2 h was noted in 14 eyes (66.7%) in the standard group and none (0%) in the OVD-free group ( < 0.001). The rise in IOP from baseline was significantly higher at 2 h in the standard group (10.5 ± 5.2 mmHg vs. 2.2 ± 3.3 mmHg, difference: 8.3, 95% CI 5.8 to 10.8;  < 0.001). There was a significant difference in the time course of LogMAR CDVA changes between the two groups ( = 0.047). The LogMAR CDVA was significantly better in the OVD-free method group compared to the standard group at 1 day (- 0.076, 95% CI - 0.134 to - 0.018;  = 0.012), 1 week (- 0.071, 95% CI - 0.135 to - 0.007;  = 0.03), but not at 3 months (- 0.046, 95% CI - 0.107 to 0.015;  = 0.134). There was no significant difference in the time course of SE changes between the two groups ( = 0.471;  = 0.705). In the OVD-free group, mean endothelial cell loss was 4.6% at 3 months (2522 ± 281 vs. 2407 ± 226 cells/mm, difference: -115, 95% CI - 295 to 65;  = 0.187). No complications were reported in both groups except for the early IOP elevation in the standard group during the observation period.

Conclusions: The OVD-free method is safe and efficient for ICL implantation. It can be a safer method of ICL implantation compared to the standard method in that it completely eliminates ophthalmic viscoelastic devices-related complications without causing additional complications.
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http://dx.doi.org/10.1186/s40662-020-00185-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7137322PMC
April 2020

Constructing self-adhesive and robust functional films on titanium resistant to mechanical damage during dental implanting.

Mater Sci Eng C Mater Biol Appl 2020 May 23;110:110688. Epub 2020 Jan 23.

Hospital of Stomatology, Institute of Stomatological Research, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou 510600, China. Electronic address:

Hypothesis: Osseointegration can be enhanced by introducing bioactive polyelectrolyte-multilayer films on implant surfaces. To guarantee films to function successfully in use, keeping structural integrity during implanting is necessary, which requires films with strong adhesion and cohesion to resist the mechanical damage. Catechol is considered as the origin of amazing adhesion of mussels. We hypothesize that catechol functionalization of polyelectrolytes enables film construction on implants in a non-aggressive way, and helps films resist mechanical damages during implanting.

Experiments: With lipopolysaccharide-amine nanopolymersomes (NPs), catechol-functionalized hyaluronic acid and NPs (cHA, cNPs) as a polycation, polyanion and primer, respectively, catechol-functionalized polyelectrolyte-multilayer films (cPEMs) were constructed on substrates via Layer-by-layer self-assembly. Effects of catechol functionalization on construction, surface properties, assembly mechanisms, structural integrity, mechanical properties and cytotoxicity of cPEMs were studied.

Findings: Self-adhesive cPEMs can be constructed on substrates, which grow exponentially and are driven by coordination, covalent bonding, electrostatic interactions, hydrogen bonding, etc. cPEMs with suitable catechol concentrations can resist mechanical damage to keep structural integrity in simulated clinical implantation, show stronger adhesion and cohesion than non-catechol-functionalized films in nanoscratch and nanoindentation tests, and are non-cytotoxic to MSCs. With excellent drug-loading and cytosolic-delivery capacity of NPs, cPEM is promising in improving osseointegration of implants.
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http://dx.doi.org/10.1016/j.msec.2020.110688DOI Listing
May 2020

Repeatability of Cornea and Sublayer Thickness Measurements Using Optical Coherence Tomography in Corneas of Anomalous Refractive Status.

J Refract Surg 2019 Sep;35(9):600-605

Purpose: To assess the repeatability of epithelial, stromal, and total corneal thickness measurements with spectral-domain optical coherence tomography (SD-OCT; RTVue-XR; Optovue, Inc., Fremont, CA) in patients with myopia, keratoconus, and corneas after transepithelial photorefractive keratectomy (PRK), small incision lenticule extraction (SMILE), and femtosecond laser-assisted in situ keratomileusis (FS-LASIK).

Methods: A total of 352 eyes of 352 patients (75 myopic, 68 post-transepithelial PRK, 61 post-SMILE, 75 post-FS-LASIK, 20 mild keratoconus, and 53 advanced keratoconus eyes) were included. The epithelial, stromal, and total corneal thickness were recorded from the pachymetric map in the following four zones: (1) central 2-mm region, (2) eight paracentral regions within 2- to 5-mm diameter, (3) eight midperipheral regions within 5- to 7-mm diameter, and (4) eight peripheral regions within 7- to 9-mm diameter. Three successive scans were performed to evaluate the repeatability.

Results: For all zones up to 9-mm diameter, the coefficient of variation (CoV) for epithelial thickness measurements ranged from 1.7% to 3.5% for myopia, 2.6% to 6.2% for post-transepithelial PRK, 2.3% to 4.7% for post-SMILE, 4.0% to 6.3% for post-FS-LASIK, 2.5% to 6.2% for mild keratoconus, and 3.5% to 8.0% for advanced keratoconus. The CoV for stromal and total thickness measurements ranged from 0.2% to 2.0% for myopia, 0.7% to 4.2% for post-transepithelial PRK, 0.3% to 2.4% for post-SMILE, 0.3% to 1.9% for post-FS-LASIK, 0.6% to 3.0% for mild keratoconus, and 1.0% to 5.9% for advanced keratoconus.

Conclusions: RTVue-XR SD-OCT showed excellent repeatability when generating the pachymetric map in myopic eyes. Measurements, especially for epithelial thickness, were relatively more variable for corneas with keratoconus and those having undergone keratorefractive surgery. [J Refract Surg. 2019;35(9):600-605.].
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http://dx.doi.org/10.3928/1081597X-20190806-03DOI Listing
September 2019

Changes and Diurnal Variation of Visual Quality after Orthokeratology in Myopic Children.

J Ophthalmol 2018 15;2018:3174826. Epub 2018 Oct 15.

The Eye Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.

Purpose: To assess the changes and the diurnal variation of visual quality after orthokeratology in myopic children.

Methods: Forty-four eyes of 22 subjects with a mean age of 10.55 ± 1.53 years (8 to 14 years) were enrolled in this prospective study. Their spherical equivalent ranged from -1.25 to -4.25 diopters (D) and astigmatism was less than 1.00 D. Parameters including corneal curvature, ocular objective scatter index (OSI), the modulation transfer function (MTF), root mean square of ocular and corneal wavefront aberrations, and contrast sensitivity function (CSF) were measured before and at two time points during the same day after 1 month of orthokeratology.

Results: After orthokeratology, uncorrected visual acuity (UCVA) and spherical equivalent were significantly improved from baseline ( < 0.001), and their diurnal variation was not significant (=0.083, 0.568). OSI increased from 0.29 ± 0.15 to 0.65 ± 0.31 ( < 0.001). MTF decreased significantly ( < 0.01). Corneal curvature and ocular total aberration decreased ( < 0.001), while the ocular and corneal higher-order aberration increased significantly ( < 0.01). The CSF under photopic condition decreased at 3 cpd (=0.006) and increased at 18 cpd (=0.012). The diurnal variation of CSF at 18 cpd under mesopic and high glare conditions and at 12 cpd under photopic condition was significant (=0.002, 0.01, 0.017).

Conclusions: Orthokeratology can effectively improve UCVA and high spatial frequency CSF by decreasing the low-order aberrations. However, MTF and CSF at low spatial frequency decreased because of the increase of intraocular scattering and high-order aberrations. Meanwhile, CSF at high spatial frequency fluctuates significantly at two times during the same day after 1 month orthokeratology.
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http://dx.doi.org/10.1155/2018/3174826DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6205316PMC
October 2018

Comparative transcriptome profiling of genes and pathways involved in leaf-patterning of Clivia miniata var. variegata.

Gene 2018 Nov 1;677:280-288. Epub 2018 Aug 1.

College of Horticulture, Shenyang Agricultural University, Shenyang 110866, Liaoning, China. Electronic address:

Clivia miniata var. variegata (Cmvv) typically possesses yellow- and green-striped leaves. The striped plant not only has a high ornamental value but also be suitable for photosynthesis and chloroplast development research. Our previous study had revealed that yellow stripes (YSs) of Cmvv leaves contain chlorophyll-less ineffective chloroplasts. However, mechanism of Cmvv variegation is yet to be investigated. In the study, transcriptomes of both the YSs and green stripes (GSs) from single Cmvv leaves were compared using high-throughput sequencing. A total of 688 differential expression genes (DEGs) were identified based on biological replications. The qRT-PCR results indicated that transcriptome profiles accurately reflected global transcriptome differences between YSs and GSs. Subcellular localization analysis suggested that 56 DEG proteins were targeted to chloroplasts, and might be involved in anterograde signaling and leaf patterning. Moreover, the DEGs were mostly enriched in photosynthesis and plant-pathogen interaction KEGG pathways. Meanwhile, there should be coordination interaction between the two pathways. Seven of the eight DEGs involved in photosynthesis KEGG pathway were chloroplast-encoded genes and distributed among different cistrons of chloroplast DNA (cpDNA) large single copy regions (LSC) which are more prone to mutation. It was proposed that the YSs were caused by mutation(s) in cpDNA LSC. Thus, when the primary zygote of Cmvv was chimeric in LSC, leaf might be yellow- and green-striped. The study would give new insights into plant variegation and offers candidate genes to guide future research attempting to breed variegated plants.
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http://dx.doi.org/10.1016/j.gene.2018.07.075DOI Listing
November 2018

Application of case teaching in genetics courses to students majoring in forestry.

Yi Chuan 2017 Oct;39(10):939-946

Department of Forest Genetic Breeding, College of Forestry, Shenyang Agricultural University, Shenyang 110866, China.

Undergraduate students majoring in forestry generally reflect that genetics is one of the most difficult compul-sory courses, because the traditional teaching method is difficult to satisfy their needs. According to the theoretical charac-teristics of forestry and actual demands of the students, in the light of teaching and research experience in recent years, we adopted a series of typical genetic cases such as 'opening coffin to identify relatives', stem-throne of Lycium ruthenicum Murr, and magic powers in Harry Potter. Our practices revealed that the case teaching in genetics could train good personality traits, learning abilities and creativity of the students, stimulate their interests and initiatives in learning, and increase systematic learning.
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http://dx.doi.org/10.16288/j.yczz.17-237DOI Listing
October 2017

Posterior corneal surface differences between non-laser in situ keratomileusis (LASIK) and 10-year post-LASIK myopic eyes.

Acta Ophthalmol 2018 Mar 24;96(2):e127-e133. Epub 2017 Oct 24.

School of Ophthalmology and Optometry and Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China.

Purpose: To evaluate the posterior corneal surface differences between non-laser in situ keratomileusis (LASIK) and 10-year post-LASIK myopic eyes.

Methods: The study included 130 eyes from 65 patients, who were treated with myopic LASIK 10 years ago. In addition, 130 eyes from 65 unoperated myopic patients of matching present age and preoperative refraction were divided into control group. Data on the posterior corneal surface and anterior chamber were obtained from Pentacam software and compared between the groups. Postoperative visual acuity (VA) and refractive error were also analysed.

Results: The mean preoperative spherical equivalent (SE) was -6.99 ± 1.78 dioptre (D) in the LASIK group. Ten years after surgery, the mean SE was -0.45 ± 1.22 D, the efficacy index was 0.98, and the safety index was 1.01. The posterior corneal elevations of the LASIK group at 2 mm corneal diameter were significantly lower than those of the control group. However, posterior corneal elevations at 6 mm corneal diameter were higher in the LASIK group than the controls (p < 0.01 for all). The mean Q-values of posterior corneal surface demonstrated significant positive direction compared to that of control eyes at 6 and 7 mm corneal diameters (p < 0.05 for both). At the thinnest point of the cornea, the anterior chamber depths were shallower in the LASIK group than in controls. Meanwhile, the anterior chamber volumes (ACV) were smaller in the LASIK group than in the control group.

Conclusion: Our results demonstrated that the posterior corneal surface tends to show signs of central flattening and peripheral steepening 10 years after myopic LASIK surgery compared to that of non-operated myopic eyes.
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http://dx.doi.org/10.1111/aos.13532DOI Listing
March 2018

Comparison between toric and spherical phakic intraocular lenses combined with astigmatic keratotomy for high myopic astigmatism.

Eye Vis (Lond) 2017 18;4:20. Epub 2017 Aug 18.

The Eye Hospital of Wenzhou Medical University, 270 Xueyuan West Road, Wenzhou, 325000 Zhejiang People's Republic of China.

Background: To compare the outcomes of a toric phakic intraocular lens (PIOL) and a spherical PIOL combined with astigmatic keratotomy (AK) for the correction of high myopic astigmatism.

Methods: This study enrolled patients with high myopic astigmatism, including 30 eyes (22 patients) that received a toric PIOL implantation (TICL group), and 32 eyes (24 patients) that received combined AK and a spherical PIOL implantation (AK+ ICL group). The outcomes were compared between the two groups before surgery, and at the following time points after surgery: 1 week, 1, 3, 6 months, and 1, 2 years.

Results: Preoperatively, the mean manifest spherical equivalent (SE) was -14.14 ± 2.12 D in the TICL group and -14.83 ± 2.79 D in the AK + ICL group ( = 0.28), and the mean manifest refractive cylinder, -2.87 ± 1.09 D and -2.58 ± 0.85 D, respectively ( = 0.28). Two years postoperatively, the mean safety index was 1.53 ± 0.55 in the TICL group and 1.60 ± 0.70 in the AK + ICL group ( = 1.00), and the mean efficacy index, 1.18 ± 0.45 and 1.38 ± 0.52, respectively ( = 0.86). The mean manifest refractive cylinder correction was 1.94 ± 1.07 D in the TICL group and 1.39 ± 0.71 D in the AK + ICL group ( = 0.02). The mean changes in SE and refractive cylinder from 1 week to 2 years were less than 0.50 D in both groups.

Conclusions: Both TICL implantation and AK + ICL implantation are a good alternative for correction of astigmatism in addition to high myopia. TICL implantation has better predictability in correction of high myopic astigmatism.

Trial Registration: NCT03202485.
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http://dx.doi.org/10.1186/s40662-017-0085-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5561629PMC
August 2017

In Vivo Observation of Lens Regeneration in Rat Using Ultra-Long Scan Depth Optical Coherence Tomography.

Invest Ophthalmol Vis Sci 2016 12;57(15):6615-6623

The Eye Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.

Purpose: To evaluate morphologic changes of lens regeneration in rats in vivo after extracapsular lens extraction (ECLE) by ultra-long scan depth optical coherence tomography (UL-OCT).

Methods: A total of 42 Sprague-Dawley rats were used in this study. We performed ECLE on the right eyes of animals in the surgery group (n = 34). Biomicroscopy and UL-OCT scans were carried out for the surgery group immediately (within 1 hour postoperatively) and at days 1 and 3, weeks 1 and 2, and months 1, 2, and 3 postoperatively. After in vivo examination, three animals of the surgery group were euthanized at each time point for histology study, while the other 10 animals were examined continuously at those time points. The regenerated lens was evaluated in OCT images at 2 and 3 months postoperatively. The control group consisted of eight untreated rats that had OCT examination at the age of 5 months.

Results: Lens regeneration could be observed from 2 weeks postoperatively. Regeneration was mainly at the peripheral capsular bag in the first month and central region thereafter. The average thickness of regenerated lenses was 2222 ± 309 and 2324 ± 352 μm at 2 and 3 months, respectively. Regeneration was faster in the first 2 months and slowed down thereafter. Although anterior capsule opening and posterior capsule adhesion and wrinkling existed, the regenerated lens still could form a relatively regular shape, however, the size was much smaller than that of the normal lenses from rats with the same age.

Conclusions: Ultra-long OCT provides longitudinal data of the process of lens regeneration on a single individual rat in vivo, which may allow one to follow and compare the lens regenerative process under different interventions or therapy after ECLE in rats.
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http://dx.doi.org/10.1167/iovs.16-19363DOI Listing
December 2016

Safety of femtosecond laser-assisted cataract surgery: assessment of aqueous humour and lens capsule.

Acta Ophthalmol 2016 Nov 25;94(7):e534-e540. Epub 2016 Apr 25.

The Eye Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.

Purpose: To investigate the effect of femtosecond laser-assisted cataract surgery (FLACS) on aqueous humour and lens capsule.

Methods: This prospective randomized comparative study enrolled 19 eyes that underwent FLACS as the trial group and 20 eyes that underwent conventional phacoemulsification as the control group. The femtosecond laser platform (LLS-fs 3D; LensAR, Orlando, FL, USA) was used to generate capsulotomy (laser energy 8 μJ) and lens fragmentation (laser energy 10 μJ). Morphology of the cutting edge and cells of anterior capsule was assessed by light microscopy. The proteins in the aqueous humour were identified by mass spectrometry (Ultraflex III TOF/TOF; Bruker Dalton, Bremen, Germany). Electrolyte in the aqueous humour was detected by a chemistry analyzer (Aeroset Clinical Chemistry Analyzer; Abbott Laboratories, Abbott Park, IL, USA).

Results: The cutting edge of anterior capsule was saw-tooth-shaped under magnification of 200× and 400× in the trial group, while it was smooth in the control group. Intact cells were found in the boundary area next to the cutting edge of anterior capsule in both groups. β-Crystallin B1, γ-crystallin S and transferrin were detected in the aqueous humour in the trial group. The concentrations of K , Na and Cl in the aqueous humour in the trial group differed significantly from those in the control group (p = 0.02, 0.03 and 0.04, respectively).

Conclusion: Femtosecond laser-assisted cataract surgery (FLACS) causes release of transferrin and crystallin from lens to aqueous humour and results in significant changes in the concentrations of K , Na and Cl in aqueous humour. However, these changes due to FLACS have no clinical significance or toxicity.
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http://dx.doi.org/10.1111/aos.13022DOI Listing
November 2016

A Cataract Surgery Training Program: 2-Year Outcome After Launching.

J Surg Educ 2016 Sep-Oct;73(5):761-7. Epub 2016 Apr 29.

The Cincinnati Eye Institute, University of Cincinnati, Cincinnati, Ohio.

Background: To investigate whether a short-term training program can produce competent cataract surgeons.

Methods: This observational pilot study enrolled 12 trainees who could not perform phacoemulsification independently. The training consisted of 2 phases. During the first 3-month phase, trainees were taught phacoemulsification through wet laboratory exposure and deliberate practice in patients at the training center in the Eye Hospital of Wenzhou Medical University in China. The second phase consisted of performing 50 cases at the trainees׳ home institution with supports from instructors of the first phase. Trainees׳ surgical results were followed-up. The surgical skill as measured by the Ophthalmology Surgical Competency Assessment Rubric (OSCAR) and surgical outcomes were analyzed.

Results: During the first phase trainees performed 193.3 ± 95.4 wet laboratory cases and 557 eyes in patients. The complication rate was 0.54%. The OSCAR scores improved significantly (p < 0.01) in the first phase. At the second phase, all the trainees could carry out phacoemulsification at their home hospital and the complication rate was 1.87%. During the long-term follow-up, 4936 cases of phacoemulsification were performed and the complication rate was 0.87%.

Conclusions: Trainees succeeded in performing phacoemulsification safely and skillfully through a limited short period of training by wet laboratory exposure, deliberate practice in patients, and frequent formative feedback provided by the OSCAR tool.
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http://dx.doi.org/10.1016/j.jsurg.2016.03.012DOI Listing
March 2017

The efficacy and safety of posterior scleral reinforcement using genipin cross-linked sclera for macular detachment and retinoschisis in highly myopic eyes.

Br J Ophthalmol 2016 11 25;100(11):1470-1475. Epub 2016 Feb 25.

The Eye Hospital of Wenzhou Medical University, Wenzhou, China.

Background/aims: To evaluate the efficacy and safety of posterior scleral reinforcement (PSR) using genipin cross-linked sclera as the material to treat macular detachment and retinoschisis, both without macular hole, in highly myopic eyes.

Methods: Twenty-one patients with highly myopic eyes (24 eyes) with macular detachment and retinoschisis were treated sequentially with genipin cross-linked PSR and were followed for at least 1 year after surgery. The best-corrected visual acuity (BCVA), spherical equivalent (SE) power, axial length (AL), optical coherence tomography, and the complications were evaluated.

Results: The mean SE decreased from -13.81±4.67 D preoperatively to -9.64±4.86 D postoperatively, while the improvement in the logMAR BCVA values was from 1.24±0.57 before surgery to 1.03±0.57 after surgery. The preoperative AL (29.73±2.31 mm) was decreased (28.08±2.08 mm) after the operation. The retina in 21 eyes (87.5%) was successful reattached and the macular detachment was significantly decreased in two eyes; a macular hole occurred in one eye.

Conclusions: For at least a 1 year period of follow-up, PSR with genipin cross-linked sclera was safe and effective to treat macular detachment and retinoschisis in high myopia when a macular hole was not present. The reinforcement effect tended to be stabilised and maintained for 6 months after treatment.
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http://dx.doi.org/10.1136/bjophthalmol-2015-308087DOI Listing
November 2016

Pupil Dilation with Intracameral Epinephrine Hydrochloride during Phacoemulsification and Intraocular Lens Implantation.

J Ophthalmol 2016 20;2016:4917659. Epub 2016 Jan 20.

The Eye Hospital of Wenzhou Medical University, Wenzhou 325000, China.

Objective. To investigate mydriatic effect of intracamerally injected epinephrine hydrochloride during phacoemulsification and intraocular lens (IOL) implantation. Methods. Eighteen cataract patients for bilateral phacoemulsification were enrolled. To dilate pupil, one eye was randomly selected to receive intracamerally 1 mL epinephrine hydrochloride 0.001% for 1 minute after corneal incision (intracameral group), and the contralateral eye received 3 drops of compound tropicamide 0.5% and phenylephrine 0.5% at 5-minute intervals 30 minutes before surgery (topical group). Pupil diameters were measured before corneal incision, before ophthalmic viscoelastic device (OVD) injection, after OVD injection, before IOL implantation, and at the end of surgery. Results. At each time point, the mean pupil diameter in the intracameral group was 2.20 ± 0.08, 5.09 ± 0.20, 6.76 ± 0.19, 6.48 ± 0.18, and 5.97 ± 0.24 mm, respectively, and in the topical group it was 7.98 ± 0.15, 7.98 ± 0.15, 8.53 ± 0.14, 8.27 ± 0.16, and 7.93 ± 0.20 mm, respectively. The topical group consistently had larger mydriatic effects than the intracameral group (P < 0.05). The onset of mydriatic effect was rapid in the intracameral group. There was no difference in surgical performance or other parameters between groups. Conclusions. Intracameral epinephrine hydrochloride appears to be an alternative to the mydriatic modalities for phacoemulsification and IOL implantation. In comparison with topical mydriatics, intracameral epinephrine hydrochloride offers easier preoperative preparation, more rapid pupil dilation, and comparable surgical performance.
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http://dx.doi.org/10.1155/2016/4917659DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4745390PMC
February 2016

Leaf patterning of Clivia miniata var. variegata is associated with differential DNA methylation.

Plant Cell Rep 2016 Jan;35(1):167-84

Key Message: Leaf patterns (yellow, green and striped) of Clivia miniata var. variegata might be caused by differential DNA methylation in CCGG sites in response to heterogeneous environmental pressure. Clivia miniata is an important ornamental plant.Clivia miniata var. variegata (Cmvv) is a variegated leaf mutant of C. miniata. Typical Cmvv has attractive green and yellow-stripped leaves. The study has revealed that an explant of Cmvv, even a full-green explant, could regenerate plants of three different types: yellow, green, ands triped; normal-appearing chloroplasts were found in guard cells but not in mesophyll cells of all the three types of Cmvv using confocal laser scanning microscopy (CLSM).Thus, we speculated that cells of the three types of Cmvv had an identical mutation and the mutation might disturb mesophyll cell chloroplast biogenesis after symplastic isolation of guard cells. Using CLSM and methylation sensitive amplification polymorphism (MSAP), we found that (a) striped leaves of Cmvv are due to sectorial decreases in chlorophyll levels and the decreases are associated with CG hypermethylation; (b) extent of epigenetic divergence among the three types of Cmvv leaves is positively correlated with intensity of leaf-color difference; and (c) green stripes of two plants are clustered in one group based on the MSAP profiles, but green and yellow stripes of a plant are not. Sequencing analysis indicated that CG hypermethylation in gene bodies of CPSAR1 and ycf2 might lead to gene silencing and yellow leaves/stripes of Cmvv. All together, it is possible that cytosine methylation involved regulating leaf color of Cmvv, also striped pattern of Cmvv might be caused by differential DNA methylation in response to heterogeneous environmental pressure. Furthermore, a novel leaf-color epigenetic hypothesis was proposed in this article.
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http://dx.doi.org/10.1007/s00299-015-1877-7DOI Listing
January 2016

Preliminary clinical investigation of cataract surgery with a noncontact femtosecond laser system.

Lasers Surg Med 2015 Nov 27;47(9):698-703. Epub 2015 Aug 27.

The Eye Hospital of Wenzhou Medical University, China, 270 Xueyuan West Road, Wenzhou, 325000, Zhejiang, P.R. China.

Background And Objective: Femtosecond laser-assisted cataract surgery (FLACS) is rapidly gaining popularity due to the improved consistency and predictability for capsulorhexis. This study aimed to investigate the preliminary clinical outcomes of FLACS with a noncontact femtosecond laser system.

Patients And Methods: This prospective study enrolled 25 eyes in the trial group underwent FLACS (LLS-fs 3D, LENSAR, USA), and 29 eyes in the control group underwent conventional cataract surgery (Stellaris, Bausch & Lomb, USA). The phacoemulsification time, energy, and complications during operation were recorded. Postoperative refraction at 1 day, 1 week, 1 and 3 months, the capsulorhexis size and corneal endothelial density at 1 and 3 months were also measured.

Results: Compared to the control group, reduction in phacoemulsification time was 51.5% (P = 0.02), and in overall energy, 65.1% (P = 0.02) in the trial group. In the trial group and the control group, total time of cataract procedure was 10.04 ± 1.37 minutes, 10.52 ± 1.92 minutes, respectively (P = 0.31); the absolute difference between attempted and achieved capsulorhexis diameter at 1 month was 192.9 ± 212.0 µm, 626.9 ± 656.6 µm, respectively (P = 0.04), and at 3 months, 256.6 ± 181.9 µm, 572.1 ± 337.0 µm, respectively (P= 0.03); the absolute difference between attempted and achieved spherical equivalent at 3 months was 0.16 ± 0.16 D, 0.74 ± 0.65 D, respectively (P < 0.01); mean corneal endothelial cell loss at 1 month was 15.6% and 14.2%, respectively (P = 0.77), and at 3 months, 2.9%, 4.2%, respectively (P = 0.50).

Conclusions: With the noncontact femtosecond laser system, FLACS can significantly improve the accuracy and repeatability of capsulorhexis, reduce the phacoemulsification time and overall energy, and enhance the predictability and stability of postoperative refraction.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5049591PMC
http://dx.doi.org/10.1002/lsm.22405DOI Listing
November 2015

Allopurinol protects against ischemic insults in a mouse model of cortical microinfarction.

Brain Res 2015 Oct 14;1622:361-7. Epub 2015 Jul 14.

Department of Neurology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China.

Microinfarcts are common in patients with cognitive decline and dementia. Allopurinol (ALLO), a xanthine oxidase (XO) enzyme inhibitor, has been found to reduce proinflammatory molecules and oxidative stress in the vasculature. We here examined the effect of pre-treatment with allopurinol on the cortical microinfarction. C57BL/6J mice were subjected to a permanent single penetrating arteriole occlusion induced by two-photon laser irradiation. Infarction volume, the activation of glial cells and nitrosative stress in the ischemic brain was assessed using immunohistochemistry. Pre-treatment with ALLO achieved 42% reduction of infarct volume and significantly reduced microglia infiltration, astrocyte proliferation and nitrosative stress in the ischemic brain. These data indicate that ALLO protects against microinfarcts possibly through inhibition of nitrosative stress and attenuation of microglia infiltration as well as astrocytes reactivation.
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http://dx.doi.org/10.1016/j.brainres.2015.07.010DOI Listing
October 2015

Effect of translation and rotation fitting on analysis of corneal topography.

J Med Eng Technol 2015 17;39(6):309-15. Epub 2015 Jul 17.

Eye Hospital, WenZhou Medical University , Wenzhou , PR China .

The purpose was to assess the suitability of quadratic equations for the accurate representation of corneal topography and consider the effect of translation and rotation fitting on the quality of fit and the curvature results. Topography images were recorded for the anterior and posterior surfaces of 490 corneas of 490 myopic patients using Pentacam. Elevation data were fitted to four shape models, three of which considered translational and/or rotational fitting. Differences between the models in the estimates of radii of curvature (R) and asphericity coefficients (Q) and in the quality of fit (as measured by the root mean square (RMS) error and the structural similarity index (SSIM)) were statistically analysed. The general shape model that considered both translational and rotational misalignments provided the best fit for the anterior (RMS = 1.18 ± 0.56 µm, SSIM = 0.99 ± 0.01) and posterior (RMS 3.64 ± 1.23 µm, SSIM = 0.99 ± 0.01) corneal surfaces in all subjects. The quality of fit degraded significantly (with p < 0.01 in all cases) when misalignments were not considered, increasing RMS to 5.20 ± 2.27 µm (anterior) and 17.10 ± 6.08 µm (posterior) and decreasing SSIM to 0.84 ± 0.18 (anterior) and 0.68 ± 0.22 (posterior) when both translational and rotational misalignments were ignored. The estimates of Rx, Ry, Qx and Qy as obtained when both forms of misalignment were considered varied, respectively, by as much as 0.18 mm, 0.23 mm, 0.27 and 0.54 for the anterior surface, and 0.25 mm, 0.39 mm, 0.32 and 0.37 for the posterior surface when misalignments were ignored. The variations were statistically significant, with p remaining below 0.01 in all cases. In conclusion, consideration of geometric misalignments helps improve the accuracy of describing corneal topography. The effects of misalignments on the estimates of corneal radius and asphericity are statistically significant and may in some cases be clinically significant.
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http://dx.doi.org/10.3109/03091902.2015.1040174DOI Listing
May 2016

Repeatability and reproducibility of a double-pass optical quality analysis device.

PLoS One 2015 3;10(2):e0117587. Epub 2015 Feb 3.

The Eye Hospital of Wenzhou Medical University, Wenzhou, China.

Purpose: To evaluate the repeatability and reproducibility of a double-pass instrument (OQASII, Visiomereics SL, Spain), which objectively measures overall optical quality of the human eyes.

Methods: The right eye of 119 healthy subjects with best corrected visual acuity of 20/25 or better was included in this prospective, comparative, observational study. Two separate tests with OQASII were conducted sequentially on the same day by two different examiners. A week later, the first examiner conducted the third measurement. All subjects underwent three consecutive tests during each session. The repeatability and reproducibility of the modulation transfer function cut off frequency (MTF cutoff), the Strehl ratio, the OQAS values (OVs) at contrasts of 100%, 20% and 9%, and the objective scatter index (OSI) were analyzed.

Results: For MTF cutoff, Strehl ratio, OV100%, OV20%, OV9%, and OSI, the mean values were 39.32±9.75cpd, 0.22±0.06, 1.31±0.33, 1.33±0.39, 1.33±0.41, 0.60±0.42, respectively. Repeatability and reproducibility were good with a very low coefficient of variation and high interclass correlation coefficients (>0.88) for all parameters. Bland-Altman plots showed good correlation with 95% limits of agreement ranged from -6.04 to 6.78cpd, -0.05 to 0.05, -0.20 to 0.23, -0.29 to 0.32, -0.40 to 0.42, -0.23 to 0.21 in inter-observer, and -6.56 to 7.42cpd, -0.06 to 0.06, -0.22 to 0.24, -0.30 to 0.32, -0.35 to 0.34, -0.24 to 0.23 in inter-visit, respectively.

Conclusion: The OQASII system yields excellent repeatability and good reproducibility for objective measurements of overall optical quality in clinic.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0117587PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4315520PMC
January 2016

Correlation among lens opacities classification system III grading, visual function index-14, pentacam nucleus staging, and objective scatter index for cataract assessment.

Am J Ophthalmol 2015 Feb 1;159(2):241-7.e2. Epub 2014 Nov 1.

The Eye Hospital of Wenzhou Medical University, Wenzhou, China. Electronic address:

Purpose: To investigate the relationship among Lens Opacities Classification System III (LOCS III) grading score, Visual Function Index-14 (VF-14) score, average lens density by the Pentacam Nucleus Staging system, and the objective scatter index measured by the Optical Quality Analysis System in age-related cataract patients.

Design: Prospective, single-center, cross-sectional study.

Methods: Thirty-six subjects (60 eyes) with age-related cataract were recruited. Subjects with any corneal anomaly potentially affecting intraocular scatter were excluded. The best-corrected visual acuity (BCVA), LOCS III nuclear opalescence score and cortical cataract score, VF-14 score, average lens density, and objective scatter index were obtained. Correlations among these parameters were analyzed.

Results: The LOCS III nuclear opalescence score was correlated with the BCVA (r = 0.438; P = .001), objective scatter index (r = 0.543; P < .001), and average lens density (r = 0.621; P < .001). The objective scatter index was also correlated with the BCVA (r = 0.779; P < .001) and the average lens density (r = 0.320; P = .013). The VF-14 score had the strongest correlation with the objective scatter index (r = -0.712; P < .001). The difference between groups with objective scatter index<3.0 and ≥3.0 was significant with regard to BCVA, average lens density, LOCS III nuclear opalescence score, and VF-14 score.

Conclusions: LOCS III grading remains an economical and effective method to assess lens opacities, especially in the formation of early cortex cataracts. The objective scatter index can be a useful parameter to objectively analyze the correlation between ocular examination findings and patient concerns. Furthermore, the objective scatter index scores ≥3.0 can be a possible objective cut-off for preoperative decision making.
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http://dx.doi.org/10.1016/j.ajo.2014.10.025DOI Listing
February 2015

Rugate filters used in slit-lamp delivery to improve color rendering of illumination for retinal photocoagulation.

Appl Opt 2014 May;53(15):3361-9

Laser filters and color filters used in slit-lamp delivery have been developed by the rugate approach to improve color rendering of illumination for retinal photocoagulation. The double-notch laser filter is designed according to the required laser lines and incident angle. Based on the transmission spectrum of a double-notch laser filter and the spectral power distribution (SPD) of the light source of a slit lamp, a scanning search algorithm is applied to find the optimal transmission spectrum of a multi-notch color filter for the best color rendering index of illumination. Open-source software is used to design the refractive index profile of the rugate filters, which are deposited by the reactive pulse magnetron sputtering. Both the theoretical analysis of SPD of slitlamp delivery with consideration of the deposited rugate filters and the experimental results demonstrate that the color rendering property of illumination can be improved remarkably, thus making fundus observation and retinal laser photocoagulation more reliable and efficient.
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http://dx.doi.org/10.1364/AO.53.003361DOI Listing
May 2014

[Impact factor of timeliness lag for seeing a doctor about cataract patient in Wenzhou region of Zhejiang province].

Zhonghua Yi Xue Za Zhi 2013 Nov;93(41):3312-4

Affiliated First Hospital of Wenzhou Medical University, Wenzhou 325000, China; 325027 Affiliated Eye Hospital of Wenzhou Medical University,

Objective: Investigation the impact factor of timeliness lag about cataract patient of operation.

Methods: Through Opportunistic Screening , from January 2007 to January 2012, we extracted people aged 50 or above and carried out the cataract screening in 10 towns of Wenzhou region of Zhejiang province. People extracted was checked by slit lamp microscope and ophthalmoscope directly, and the people who are suit for operation were brought to a first-rate of level three eye hospital and operated by MSICS . At the same time we have made questionnaire about five aspect including basic situation, economic status, basic life status, health and medical status and health needs for the operator and this questionnaire involves twenty-three relevant indexes about the timeliness, these factors of timeliness for patients seeing a doctor are judged.

Results: 36 681 people are checked for five years and 10 326 people(10 326 eyes) are suitable for surgery. Through analyzing sixteen relevant indexes about the timeliness , there are ten indexes which have Statistical Significance including in transportation, the distance for nearest medical aid post , care knowledge, population of family, income of family, respondents degree , the highest degree of family members type of work, structure of building, government subsidies. The first reason that the people can't be operated in time are economic difficulties, next are older and making children trouble for seven factors of no operation in time. The people for this three reason is more than 75% for not seeing a doctor in time.

Conclusion: The key work of blindness prevention and treatment is the cataract surgery for our country.Eye doctors pay attention to new surgical technique , at the same time we should promote MSICS which is technique of low cost and have good effect of the operation.
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November 2013

Influence of glucocorticosteroids on the biomechanical properties of in-vivo rabbit cornea.

J Mech Behav Biomed Mater 2014 Jan 28;29:350-9. Epub 2013 Aug 28.

School of Optometry and Ophthalmology and Eye Hospital, Wenzhou Medical College, Wenzhou, Zhejiang Province 325027, China; The Central Hospital of Wuhan, No. 26, Shengli street, Jiang'an District, Wuhan, Hubei Province 430000, China.

Understanding corneal biomechanical responses during long-term glucocorticosteroids administration is important in clinical practice. The purpose of this study is to investigate the biomechanical influence of fluorometholone 0.1% eye drops on rabbit cornea. Thirty-eight Japanese white rabbits were randomly divided into three groups; a fluorometholone group, a supernatant group and a blank control group. For each rabbit in fluorometholone group, one cornea was treated with fluorometholone 0.1% eye drops four times a day for 8 weeks, while corneas of rabbits in supernatant group were treated in the same frequency with supernatant fraction centrifuged from fluorometholone 0.1% eye drops. The rabbits in the blank control group were not given any treatment. At the end of the 8 week observation period, the rabbits were euthanized and the eyes immediately enucleated and prepared for inflation testing. The experimental pressure-deformation data was used to derive the stress-strain behavior of each eye using an inverse modeling procedure. Comparisons of mechanical stiffness of corneas were conducted among the three groups to determine the influence of fluorometholone. The results showed that corneal stiffness decreased as the fluorometholone administration time prolonged. Comparisons of tangent modulus indicated average stiffness reductions of 34.2% and 33.5% in the fluorometholone group compared to the supernatant and control groups, respectively, at the end of the observation period. The stiffness-reduction effect of fluorometholone on the cornea should be considered in clinical management, especially when administrating it to biomechanically weakened corneas, such as after refractive surgeries and in cases of keratoconus.
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http://dx.doi.org/10.1016/j.jmbbm.2013.08.015DOI Listing
January 2014

[Repeatability and agreement of corneal thickness measurement with Pentacam Scheimpflug photography and Visante optical coherence tomography].

Zhonghua Yan Ke Za Zhi 2013 Mar;49(3):250-6

School of Optometry and Ophthalmology, Wenzhou Medical College, Wenzhou, China.

Objective: To evaluate the repeatability and agreement of central and peripheral corneal thickness (CT) measurements by high resolution Pentacam rotating Scheimpflug photography and Visante optical coherence tomography (OCT) in unoperated myopic eyes and eyes after Laser In Situ Keratomileusis (LASIK).

Methods: CT at central, thinnest, 1.0 mm and 2.5 mm superior, inferior, nasal and temporal periphery locations, and the location of the corneal thinnest thickness were measured using Pentacam and Visante OCT in 60 myopia patients (60 eyes) and 60 patients (60 eyes) after LASIK. The results were analyzed by paired-t test, Pearson correlation analysis and Bland-Altman method.

Results: Both Pentacam and Visante OCT demonstrated high intraobserver repeatability, with all intraclass correlation coefficients and Cronbach's alphas were more than 0.9, and coefficient of variation were less than 0.9%. Significantly higher CoV was measured with Pentacam than by Visante OCT in at central (0.46 ± 0.30), thinnest (0.43 ± 0.28) and 1.0 mm locations in both groups (t = 2.465, 2.226, P < 0.05), but no statistically significant difference were found at 2.5 mm locations in healthy subjects and all locations in post-LASIK eyes (t = -0.518, 1.542, -0.876, 0.756, P > 0.05). The thickness of central corneal with Pentacam was (543.01 ± 22.89) µm, the thinnest point was (540.61 ± 22.84) µm, they were greater than the value of Visante OCT (t = 17.946, 23.071, P < 0.05). The Pearson correlation coefficients were all more than 0.9 (all r > 0.9, P < 0.01). The Bland-Altman plots showed the 95% LoA between both devices were lower than 22 µm at central, thinnest and 1.0 mm locations. However, the 95% LoA were 24 µm to 44 µm at 2.5 mm locations.

Conclusions: Pentacam and Visante OCT demonstrate high repeatability for central and peripheral CT measurements in young myopia and post-LASIK eyes. However, both devices can't be used interchangeably for measurements of peripheral CT.
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March 2013

Assessment of corneal biomechanical behavior under posterior and anterior pressure.

J Refract Surg 2013 Jan;29(1):64-70

School of Optometry and Opthalmology and Eye Hospital, Wenzhou Medical College, Zhejiang Province, China.

Purpose: To determine the biomechanical response of the rabbit cornea to inflation under posterior and anterior pressure.

Methods: Twelve Japanese white rabbits were included in the study. A randomly selected eye from each animal was subjected to posterior pressure in an inflation test rig, and the other eye was subjected to anterior pressure after manually reversing its curvature. Specimens were loaded by cycles of pressure up to 40 mmHg, and the experimentally obtained pressure-deformation data were used to derive the stress-strain behavior of each eye using an inverse modeling procedure.

Results: The differences between the two groups in corneal thickness, diameter, and intraocular pressure (IOP) were not statistically significant (P=.935, .879 and .368, respectively). Corneas tested under posterior pressure displayed significantly higher stiffness (as measured by the tangent modulus) than those inflated by anterior pressure (P<.001).

Conclusions: Cornea is a nonlinear viscoelastic tissue that presents different mechanical properties when tested under posterior and anterior pressure. The determination of the behavior under both forms of pressure could contribute to the construction of accurate finite element simulations of corneal behavior and the correction of tonometric IOP measurements. The difference in mechanical behavior between anteriorly and posteriorly loaded corneas in the study, although significant, could have been partly affected by the changes in microstructure possibly caused by changing corneal form to enable anterior loading.
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http://dx.doi.org/10.3928/1081597X-20121228-05DOI Listing
January 2013

[Comparison of Lenstar and IOLMaster for intraocular lens power calculation].

Zhonghua Yan Ke Za Zhi 2012 Nov;48(11):1005-10

School of Ophthalmology & Optometry of Wenzhou Medical College, Wenzhou 325027, China.

Objective: To evaluate the precision of Intraocular Lens (IOL) power calculation using a new optical low-coherence reflectometry biometer (Lenstar) and compare the results with those obtained with IOLMaster.

Methods: It was a prospective controlled study. Biometry measurements in 157 eyes of 98 cataract patients were performed by the same examiner with Lenstar and IOLMaster. Axial length (AL), corneal keratometry readings (Km), and anterior chamber depth (ACD) were obtained. Correlation and differences of biometry measurements obtained with two biometers were made. Intraocular Lens power were calculated using 4 formulas and the corresponding IOL constants, the target was emmetropia. Then statistical analysis was proceeded.

Results: Axial length were (23.65 ± 1.17) mm and (23.65 ± 1.16) mm respectively, Km (44.15 ± 1.58) D and (44.17 ± 1.58) D respectively by Lenstar and IOLMaster and no statistical differences were found (P > 0.05). ACD were (3.09 ± 0.41) mm and (3.05 ± 0.41) mm respectively by Lenstar and IOLMaster and there was statistical difference between them (P = 0.001). All biometry measurements showed good linear correlation (r > 0.9, P < 0.001). IOL power calculations with biometry values between Lenstar and IOLMaster using the 4 formulas showed good agreement. The least difference was obtained with formula SRK/T and the most with formula Haigis.

Conclusions: Lenstar can provide precise and noncontact biometry measurements easily and safely, which are welcome by patients. Providing precise and reliable biometry measurements of cataract patients for Intraocular Lens power calculation, it shows good agreement with IOLMaster and the two biometers can be interchanged.
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November 2012

[Assessments of total corneal power and intraocular lens power in post-LASIK eyes].

Zhonghua Yi Xue Za Zhi 2012 Sep;92(33):2339-44

Wenzhou Medical College, Wenzhou, China.

Objective: To compare the different evaluations of corneal power in post-laser-assisted in situ keratomileusis (LASIK) eyes and assess the accuracy and differences of intraocular lens (IOL) power prediction with corneal powers through different calculation methods.

Methods: For this prospective study, 71 eyes of 39 candidates undergoing LASIK and 3 months later returning for reexamination were included. All subjects were divided into 2 groups according to the axial length: Group A (23.46 - 25.97 mm) 44 eyes, Group B (26.00 - 28.52 mm) 27 eyes. The ranges of spherical equivalents were -1.75 - -9.50 D with an average of (-4.82 ± 1.98) D. Subjective refraction and Pentacam Scheimpflug analyzer were performed at pre-operation and subjective refraction, IOLMaster and Galilei II dual Scheimpflug analyzer at over 3 months post-operation. The following values were obtained: SimK by Galilei II dual Scheimpflug analyzer, Kn calculated with Gaussion thick lens formula, Kray with ray tracing method, Kchm calculated with clinical history method and Km by IOLMaster. Repeated measures analysis of variance analyze the differences between SimK, Kn, Kray, Km and Kchm. Repeated measurement analysis of variance was employed to analyze the differences between SimK, Kn, Kray, Km combining intraocular lens power formula and Kchm combining intraocular lens power formula. Pearson's analysis was performed to analyze the correlations between SimK, Kn, Kray, Km and Kchm. Those combining with formulas for IOL power calculations were also analyzed. P < 0.05 indicated statistical significance.

Results: The values of SimK, Kn, Kray, Km and Kchm were (39.02 ± 1.8), (37.8 ± 1.51), (36.8 ± 1.84), (39.18 ± 1.75) and (38.55 ± 1.83) D respectively. The differences between SimK, Kn, Kray, Km and Kchm had statistical significances (P < 0.01). High correlations existed between SimK, Kn, Kray, Km and Kchm (r > 0.9, P < 0.01). In the same IOL formula, Kray had the highest IOL power value, Kn followed, Kchm the third, SimK and Km the smallest. Among the IOL formulas, Haigis-L and Haigis predicted the highest IOL power, HofferQ followed, Holladay the third and SRK/T the smallest.

Conclusion: Kn/Kray combining with Haigis formula may be a new and effective method for predicting the IOL power in post-LASIK eyes.
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September 2012
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