Femtosecond laser-assisted removal of an intracorneal chestnut, a case report.

BACKGROUND: To report a case of femtosecond laser-assisted removal of an intracorneal chestnut. CASE PRESENTATION: A chestnut was obliquely protruding to the stroma of cornea and it was localized at the paracentral region on the left eye of a 32-year-old man. The best-corrected visual acuity (BCVA, in decimal values) was 0.6 in the injured eye. The white ulcers with feathery edges or satellite infiltrates were not observed in the lesion, and the anterior chamber was deep and quiet. Anterior segment optical coherence tomography (AS-OCT) demonstrated that the original entry path of the foreign body had been sealed, spanning a thickness of approximate 152 µm. In view of location of the intraocular chestnut at the paracentral region, femtosecond laser was applied according to the procedures of IntraLase Enabled Keratoplasty (IEK) to create an anterior lamellar flap rapidly and precisely. The lamellar flap was easily separated with a flap lifter, and the chestnut was removed entirely using a pair of forceps. In 3 days after surgery, the patient complained of mild pain and blurred vision. These symptoms were relieved after treatment with the eyedrops. At three-month follow-up, the corneal wound was healed well, and the BCVA was greatly improved to 1.2 in the left eye. A dot-like haze was observed corresponding to the scar at the site of foreign body removal. No surgical induction of corneal astigmatism was found in the corneal topography. CONCLUSIONS: Without induction of a visually significant scar and corneal astigmatism, the IEK procedure of femtosecond laser is of particular interest as it provides a unique method for removal of intracorneal foreign bodies impinging on the visual axis.

Eaf2 protects human lens epithelial cells against oxidative stress­induced apoptosis by Wnt signaling.

The tumor suppressor protein ELL-associated factor 2 (Eaf2) serves an important role in lens development and maturation; however, its role in oxidative stress­induced cataract formation remains unclear. In the present study, an in vitro apoptosis model was constructed by treating HLE­B3 cells with 50 µM hydrogen peroxide (H2O2), and was confirmed by flow cytometry. Subsequently, overexpression of Eaf2 was induced in H2O2­induced HLE­B3 cells by ligating Eaf2 cDNA to a pcDNA3.0 plasmid and the role of Wnt3a in the function of Eaf2 was also assessed by inhibiting the expression of the gene in Eaf2­overexpression cells. The expression levels of glycogen synthase kinase 3ß, ß­catenin, Eaf2, caspase 3, Wnt3a, B­cell lymphoma 2 (Bcl­2) and Bcl­2­associated X protein were examined using reverse transcription­quantitative polymerase chain reaction and western blot analysis. Immunocytochemistry was used to locate Eaf2 and Wnt3 protein expression in the H2O2­induced HLE­B3 cells. The results indicated that Eaf2 was able to effectively suppress H2O2­induced apoptosis of HLE cells via inhibition of caspase 3 production and activation of Wnt3a signaling. In addition, knockdown of Wnt3a in Eaf2­overexpression cells evidently counteracted the effect of Eaf2 in antagonizing H2O2­induced apoptosis. Taken together, these findings suggested that Eaf2 may suppress oxidative stress­induced apoptosis of HLE­B3 cells exerted through the activation of Wnt3a signaling.

Diabetic macular edema in proliferative stage treated with anti-vascular endothelial growth factor agent and triamcinolone acetonide by laser-based strategies.

AIM: To appraise the effect of treatment for diabetic macular edema (DME) in proliferative stage with sufficient panrentinal photocoagulation (PRP) therapy and intravitreal injections (IV) Conbercept and posterior subtenon's triamcinolone acetonide (STTA) sequential therapy. METHODS: This prospective clinical randomized controlled trial of cross-over design was conducted in three phases. The participants included cases of DME in proliferative stage. They were divided into two groups and treated with PRP before enrollment. Group A were treated with IV-Conbercept 0.5 mg for one month in the 1st phase. Group B were treated with STTA 40 mg (twice per two weeks). The interventions were exchanged in the second phase (2mo) between the two groups. In the third phase (3-6mo) no other treatment was given. Best corrected visual acuity (BCVA), central macular thickness (CMT) measured by OCT and complications were compared. RESULTS: After phase I: in Group A, BCVA improved from 0.201±0.17 to 0.37±0.24 (F=5.88, P=0.004). CMT changed from 449±155.10 to 304.1±84.70 µm (F=14.9, P<0.01). In Group B, BCVA changed from 0.195±0.19 to 0.26±0.20 (F=0.76, P=0.41) while CMT changed from 463.82±152.92 to 366.00±115.40 µm (F=3.70, P<0.03). The improvement of BCVA was better in Group A (P<0.05). After phase II: in Group A, BCVA raised to 0.47±0.27 (F=0.26, P<0.01), CMT reduced to 260.67±62.97 µm (F=-188.3, P<0.01); in Group B, BCVA raised to 0.51±0.26 (F=0.31, P<0.01), CMT reduced to 261.93±50.15 µm (F=-201.9, P<0.01). But there were no difference between two groups (P>0.05). After phase III: in Group A, BCVA maintained 0.42±0.25 (F=0.22, P=0.001), CMT maintained 267.8±58.34 µm, (F=-0.27, P<0.01); in Group B, BCVA was 0.47±0.25 (F=-0.27, P<0.01), CMT was 272.71±49.16 µm (F=-191.1, P<0.01). No serious complications happened in all phases. CONCLUSION: PRP+Conbercept is better than PRP+STTA in DME with proliferative stage but PRP+Conbercept+STTA sequential therapy may be a wiser choice for persistent effectiveness on anatomical as well as functional status.

MicroRNA-34a promoting apoptosis of human lens epithelial cells through down-regulation of B-cell lymphoma-2 and silent information regulator.

AIM: To investigate the role of microRNA-34a (miR-34a) in the induction of apoptosis of human lens epithelial (HLE-B3) cells. METHODS: The apoptosis of HLE-B3 cells was detected by Annexin V-PE apoptosis detection kit after the treatment with 200 µmol/L H2O2 for 24h and lentiviral miR-34a vector transfection. The expression of miR-34a in the cells was quantified by quantitative real time polymerase chain reaction (qRT-PCR) in response to H2O2 exposure and the vector transfection. The effects of overexpression of miR-34a on the expression of B-cell lymphoma-2 (Bcl-2) and silent information regulator 1 (SIRT1) was determined by qRT-PCR and Western blot. RESULTS: The expression of miR-34a was up-regulated by the treatment of H2O2 in HLE-B3 cells. The increased expression of miR-34a is accompanied with the cell apoptosis. Consistence with the H2O2 exposure, ectopic overexpression of miR-34a in HLE-B3 cells promoted cells apoptosis. Importantly the anti-apoptosis factors Bcl-2 and SIRT1 were reduced significantly by up-regulation of miR-34a in HLE-B3 cells. CONCLUSION: MiR-34a promotes the apoptosis of HLE-B3 cells by down-regulating Bcl-2 and SIRT1, suggesting that miR-34a may involve in the pathogenesis of cataract formation and targeting miR-34a may be a potentially therapeutic approach for treatment of cataract.

Sub-threshold micro-pulse diode laser treatment in diabetic macular edema: A Meta-analysis of randomized controlled trials.

AIM: To examine possible differences in clinical outcomes between sub-threshold micro-pulse diode laser photocoagulation (SDM) and traditional modified Early Treatment Diabetic Retinopathy Study (mETDRS) treatment protocol in diabetic macular edema (DME). METHODS: A comprehensive literature search using the Cochrane Collaboration methodology to identify RCTs comparing SDM with mETDRS for DME. The participants were type I or type II diabetes mellitus with clinically significant macular edema treated by SDM from previously reported randomized controlled trials (RCTs). The primary outcome measures were the changes in the best corrected visual acuity (BCVA) and the central macular thickness (CMT) as measured by optical coherence tomography (OCT). The secondary outcomes were the contrast sensitivity and the damages of the retina. RESULTS: Seven studies were identified and analyzed for comparing SDM (215 eyes) with mETDRS (210 eyes) for DME. There were no statistical differences in the BCVA after treatment between the SDM and mETDRS based on the follow-up: 3mo (MD, -0.02; 95% CI, -0.12 to 0.09; P=0.77), 6mo (MD, -0.02; 95% CI, -0.12 to 0.09; P=0.75), 12mo (MD, -0.05; 95% CI, -0.17 to 0.07; P=0.40). Likewise, there were no statistical differences in the CMT after treatment between the SDM and mETDRS in 3mo (MD, -9.92; 95% CI, -28.69 to 8.85; P=0.30), 6mo (MD, -11.37; 95% CI, -29.65 to 6.91; P=0.22), 12mo (MD, 8.44; 95% CI, -29.89 to 46.77; P=0.67). Three RCTs suggested that SDM laser results in good preservation of contrast sensitivity as mETDRS, in two different follow-up evaluations: 3mo (MD, 0.05; 95% CI, 0 to 0.09; P=0.04) and 6mo (MD, 0.02; 95% CI, -0.10 to 0.14; P=0.78). Two RCTs showed that the SDM laser treatment did less retinal damage than that mETDRS did (OR, 0.05; 95% CI, 0.02 to 0.13; P<0.01). CONCLUSION: SDM laser photocoagulation shows an equally good effect on visual acuity, contrast sensitivity, and reduction of DME as compared to conventional mETDRS protocol with less retinal damage.

Femtosecond laser capsulotomy versus manual capsulotomy: a Meta-analysis.

AIM: To perform a Meta-analysis on the precision and safety of femtosecond laser (FSL) capsulotomy compared with manual continuous curvilinear capsulotomy (CCC). METHODS: We searched PubMed, EMBASE, Web of Science, the Cochrane Library databases, and Clinical Trials.gov that maintained our inclusion criteria. Reference lists of retrieved articles were also reviewed. The effects of morphology of capsulorhexis and the tears of anterior capsule were calculated by using random-effect models. RESULTS: We identified 4 randomized and 7 nonrandomized studies involving 2941 eyes. The diameter of capsulotomy and the rates of anterior capsule tear showed no statistically difference between FSL group and manual group (MD=0.03; 95%CI, -0.03 to 0.09, P=0.31), and (OR=1.40; 95%CI, 0.28 to 6.97, P=0.68) respectively. In terms of the circularity of capsulotomy, FSL group had a more significant advantage than the manual CCC group (MD=0.09; 95%CI, 0.05 to 0.12, P<0.0001). CONCLUSION: Our Meta-analysis shows that FSL can perform a capsulotomy with more precision and higher reliability than manual CCC. The results in diameter of capsulotomy and the rate of anterior capsule tears was no significant difference between FSL and manual CCC groups. However in terms of circularity, the FSL was superior to the manual procedure.

Intraocular pressure and associations in children. The Gobi Desert Children Eye Study.

PURPOSE: To assess the intraocular pressure (IOP) and its association in children in a population living in an oasis in the Gobi Desert. METHODS: The cross-sectional school-based study included all schools in the Ejina region. The children underwent an ophthalmic examination, non-contact tonometry and measurement of blood pressure and body height and weight. RESULTS: Out of eligible 1911 children, 1565 (81.9%) children with a mean age of 11.9±3.5 years (range: 6-21 years) participated. Mean spherical refractive error was -1.58±2.00 diopters. In multivariate analysis, higher IOP (right eye) was associated with younger age (P<0.001; standardized coefficient beta: -0.13; regression coefficient B: -0.13; 95% Confidence interval (CI):-0.18, -0.07), higher diastolic blood pressure (P<0.001;beta:0.13;B:0.05;95%CI:0.03,0.07), higher corneal refractive power (P<0.001;beta:0.11;B:0.23;95%CI:0.12,0.34), more myopic refractive error (P = 0.035;beta: -0.06;B: -0.10;95%CI: -0.19, -0.001), and Han Chinese ethnicity of the father (P = 0.03;beta:0.06;B:0.42;95%CI:0.04,0.89). If age and diastolic blood pressure were dropped, higher IOP was associated with higher estimated cerebrospinal fluid pressure (CSFP) (P<0.001;beta:0.09; B:0.13;95%CI:0.06,0.21) after adjusting for higher corneal refractive power (P<0.001) and Han Chinese ethnicity of the father (P = 0.04). Correspondingly, higher IOP of the left eye was associated with younger age (P<0.001;beta: -0.15;B: -0.16;95%CI: -0.21, -0.10), female gender (P<0.001;beta:0.09;B:0.65;95%CI:0.30,1.01), higher corneal refractive power (P<0.001;beta:0.08;B:0.19;95%CI:0.06,0.32), more myopic refractive error (P = 0.03;beta: -0.06;B: -0.12;95%CI: -0.22, -0.01), and higher estimated CSFP (P<0.001;beta:0.11;B:0.17;95%CI:0.09,0.24). CONCLUSIONS: In school children, higher IOP was associated with steeper corneal curvature and with younger age and higher blood pressure, or alternatively, with higher estimated CSFP. Corneal curvature radius should be included in the correction of IOP measurements. The potential association between IOP and CSFP as also assumed in adults may warrant further research.

Analysis of changes in crystalline lens thickness and its refractive power after laser in situ keratomileusis.

AIM: To evaluate changes in the anterior chamber depth (ACD), crystalline lens thickness (LT) and its refractive power after laser in situ keratomileusis (LASIK). METHODS: In all cases, the preoperative and postoperative central ACD which were measured with Pentacam, Orbscan, IOL-Master and A-scan ultrasonography, central corneal true net power which was measured with the Pentacam, Orbscan and IOL-Master, axial length (AL) which was measured with IOL-Master and LT which was measured with the A-scan ultrasonography were compared using the paired sample t test. Ocular refractive errors and lens refractive power at corneal plane were calculated and their correlations were also evaluated before and after LASIK. RESULTS: At 1 week after LASIK, LT and crystalline lens refractive power at corneal plane (Dlens) which were associated with the IOL-Master and Pentacam increased significantly (P≤0.005), ACD decreased significantly (P≤0.001), but no significant increase was observed in the Dlens which was associated with the Orbscan (P=0.261). Significant correlations between the changes in the ocular refractive errors and Dlens which were associated with the Pentacam were observed at 1 week and 6 months after LASIK (P=0.028; P=0.001). CONCLUSION: LT increased significantly after LASIK, and this might partially lead to ACD decrease, Dlens increase and a small quantity of myopic regression.

[Analysis of corneal asphericity in patients after phacoemulsification].

OBJECTIVE: To investigate the distribution of corneal Q-value in the age-related cataract patients and aspherical features of cornea before and after the phacoemulsification (PHACO). METHODS: Thirty-nine eyes of 30 age-related cataract patients in our department were included. Transparent cornea incision at the temporal cornea was applied for patients with cornea astigmatism < 1.00 D and transparent cornea incision at the maximum curvature meridian for patients with cornea astigmatism > or = 1.00 D in PHACO. All patients were followed up to 3 months, corneal Q-value, corneal curvature, astigmatism were examined before and after PHACO, distribution of corneal Q-value and their correlation factors were analyzed. RESULTS: The mean corneal Q-value before and after the PHACO was -0.07 +/- 0.22 and -0.11 +/- 0.16, respectively. There was no statistical difference between the corneal Q-values before and after surgery (t = 1.14, P = 0.26). The mean of corneal curvature before and after the PHACO was (44.6 +/- 1.92) D and (44.70 +/- 1.47) D, respectively. There was no statistical difference between corneal curvature before and after the operation (t = -0.69, P = 0.50). The corneal Q-value was negatively co-related with corneal curvature before the surgery (r = -0.46, P = 0.003). The mean astigmatism power before and after the HACO was (0.67 +/- 0.43) D and (0.66 +/- 0.42) D, respectively. There was no statistical difference between astigmatism power before and after the surgery (t = -0.24, P = 0.82). There was no relationship between the corneal Q-value and astigmatism power before surgery (r = -0.24, P = 0.14). CONCLUSIONS: The corneal Q-value of aged patients is in normal distribution, is negative in the majority, and showed a negative relationship with corneal curvature. There is no statistical difference between the corneal Q-value, corneal curvature, and astigmatism power before and after PHACO surgery.