ObjectiveTo observe the efficacy of phacoemulsification with intravitreal triamcinolone injection (IVTA) in diabetic patients with severe cataract and diabetic macular edema (DME). MethodsTwenty-one patients (25 eyes) with severe cataract and DME were enrolled in this retrospective study. Fifteen eyes underwent standard phacoemulsification and intraocular lens implantation with 4 mg IVTA at completion of surgery. Ten eyes underwent standard phacoemulsification and intraocular lens implantation. All the patients were followed up for best corrected visual acuity (BCVA), optical coherence tomography(OCT) and ophthalmological examination.Changes in logarithm of he minimal angel of resolution (logMAR) BCVA and central macular thickness (CMT) were evaluated preoperatively and 1 month, 3 months and 6 months postoperatively by repeated measures ANOVA. Correlations between logMAR BCVA and CMT preoperatively and postoperatively were analyzed by Pearson correlation analysis. Postoperative 6 months logMAR BCVA and affecting factors were evaluated by multivariate linear regression analysis. ResultsBoth groups showed significant improvements of logMAR BCVA after surgery (F=4.855, 6.235; P=0.037, 0.020). There were no statistical differences of logMAR BCVA improvement at different time points postoperatively (F=0.007, 0.006, 0.023; P=0.973, 0.938, 0.882). The CMT reductions in IVTA group at month 1 and month 3 postoperatively were statistically significant than the reductions in group without IVTA(F=10.449, 7.374; P=0.012, 0.026), and there was no statistical difference of CMT reduction at month 6 postoperatively between two groups(F=2.173; P=0.114). Correlation Coefficients between CMT and BCVA were not statistically significant preoperatively and 6 months postoperatively(r=0.279, 0.172; P=0.295, 0.574). Analysis of multiple linear regression showed that external limiting membrane status and duration of diabetes are factors affecting the visual recovery (β=0.577, -0.411; P=0.025, 0.030). ConclusionsPhacoemulsification with concurrent IVTA for treatment of patients with severe cataract and DME is effective in reducing edema. But IVTA does not further improve logMAR BCVA postoperatively.
Human motion control system has a high degree of nonlinear characteristics. Through quantitative evaluation of the nonlinear coupling strength between surface electromyogram (sEMG) signals, we can get the functional state of the muscles related to the movement, and then explore the mechanism of human motion control. In this paper, wavelet packet decomposition and n:m coherence analysis are combined to construct an intermuscular cross-frequency coupling analysis model based on wavelet packet-n:m coherence. In the elbow flexion and extension state with 30% maximum voluntary contraction force (MVC), sEMG signals of 20 healthy adults were collected. Firstly, the subband components were obtained based on wavelet packet decomposition, and then the n:m coherence of subband signals was calculated to analyze the coupling characteristics between muscles. The results show that the linear coupling strength (frequency ratio 1:1) of the cooperative and antagonistic pairs is higher than that of the nonlinear coupling (frequency ratio 1:2, 2:1 and 1:3, 3:1) under the elbow flexion motion of 30% MVC; the coupling strength decreases with the increase of frequency ratio for the intermuscular nonlinear coupling, and there is no significant difference between the frequency ratio n:m and m:n. The intermuscular coupling in beta and gamma bands is mainly reflected in the linear coupling (1:1), nonlinear coupling of low frequency ratio (1:2, 2:1) between synergetic pair and the linear coupling between antagonistic pairs. The results show that the wavelet packet-n:m coherence method can qualitatively describe the nonlinear coupling strength between muscles, which provides a theoretical reference for further revealing the mechanism of human motion control and the rehabilitation evaluation of patients with motor dysfunction.
Objective To observe the features of frequency domain optical coherence tomography (FD-OCT) in acute central serous chorioretinopathy (CSC). Methods The data of FD-OCT and fundus fluorescein angiography (FFA) of 31 patients with unilateral acute CSC were retrospectively analyzed. The FD-OCT of retinal pigment epithelial (RPE) layer at leakage points, retinal detachment area and RPE layer in the fellow eyes was documented. Results Thirty-four leakage points were detected in 31 eyes on FFA. At the sites of fluorescein leakage, FD-OCT showed that serous pigment epithelial detachment (PED) in 18 leakage points (52.9%) and 17 eyes (54.8%), a small RPE protrusion in 8 leakage points (23.5%) and 8 eyes (25.8%), RPE irregularity in 6 leakage points (17.6%) and 4 eyes (12.9%) and no detectable RPE abnormality in 2 leakage points (5.9%) and 2 eyes (6.5%). An RPE defect at the edge of or within the PED was found in 7 leakage points (20.6%) and 7 eyes (22.6%). Serous retinal detachment and interruption or complete disappearance of the hyperreflective inner/outer segment junction (IS/OS) were detected in all diseased eyes. Uneven thickness of the outer segments (OS) was found in 24 eyes (77.4%), 14 of which had sagging sign. Flaking of the OS was found in 10 eyes (32.3%), multiple hyperreflective dots on the posterior surface of the detached neurosensory retina and on the surface of the RPE were found in 8 eyes (25.8%). Among 31 fellow eyes, FD-OCT also showed RPE abnormalities in 11 eyes (35.5%), in which PED, RPE protrusion and RPE irregularity were detected in 2 (6.5%), 1 (3.2%) and 8 eyes (25.8%), respectively. Conclusions In acute CSC the FD-OCT images at leakage points of are featured by PED, RPE protrusion, RPE irregularity and no detectable RPE abnormality; in retinal detachment area FD-OCT are featured by serous retinal detachment, interruption or disappearance of IS/OS, uneven thickness of OS, flaking of OS and hyper-reflective dots on the posterior surface of the detached neurosensory retina and on the surface of the RPE.