Subthreshold micropulse laser therapy for early postoperative macular thickening following surgical removal of epiretinal membrane.

BACKGROUND: This study aimed to investigate the functional and anatomical outcomes of subthreshold micropulse laser (SMPL) therapy in eyes with early postoperative macular thickening after idiopathic epiretinal membrane (iERM) removal. METHODS: This was a prospective and interventional study. Forty-eight eyes from 48 patients with macular edema at 1 month after iERM removal were randomly divided into two groups. Patients in the SMPL group (n = 24) received SMPL therapy while no special intervention was used for the observation group (n = 24). Baseline demographic data and clinical findings before and at 1 and 3 months after SMPL treatment or observation, including best-corrected visual acuity (BCVA) and the changes in central subfield thickness (CST) and average macular thickness (AMT), were analyzed. RESULTS: An improvement in BCVA with a decrease in CST and AMT from baseline to the 3-month follow-ups were observed in both SMPL and observation groups. No significant difference in BCVA was observed between the SMPL group and observation group either in the 1-month (0.26 [0.15, 0.52] vs. 0.26 [0.15, 0.39], P = 0.852) or the 3-month (0.15 [0.10, 0.30] vs. 0.23 [0.15, 0.30], P = 0.329) follow-up. There was a greater reduction in CST in the SMPL group versus observation group between baseline and the 3-month follow-up (-77.8 ± 72.3 µm vs. -45.0 ± 46.9 µm, P = 0.049). The alteration in AMT did not differ between the two groups in either 1-month (-16.5 ± 20.1 µm vs. -19.7 ± 16.3 µm, P = 0.547) or 3-month (-36.9 ± 26.9 µm vs. -34.0 ± 20.1 µm, P = 0.678) follow-up. CONCLUSIONS: SMPL therapy led to a significant decrease in CST at the 3-month follow-up while did not significantly improve the visual acuity in patients with postoperative macular thickening following iERM surgery. TRIAL REGISTRATION: The study was registered on Aug 27, 2020 (Trial Registration Number: ChiCTR 2000037227).

Surgical outcomes of macular hole and epimacular membrane treatment in patients with intraoperative amaurosis under sub-Tenon's anesthesia.

OBJECTIVE: Some patients have been found to develop intraoperative amaurosis under sub-Tenon's anesthesia. We explored whether these patients have poor surgical outcomes during mid- to long-term postoperative follow-up. METHODS: In this case series, 74 of 85 patients with macular diseases who underwent phacoemulsification combined with vitrectomy under sub-Tenon's anesthesia developed intraoperative amaurosis. The surgical outcomes at the 2- and 4-month follow-ups in these patients were investigated and compared with the outcomes in patients without amaurosis using best-corrected visual acuity (BCVA), optical coherence tomography (OCT), and pattern visual evoked potential (PVEP). RESULTS: Both BCVA and the OCT-based macular structure in patients with intraoperative amaurosis showed significant postoperative improvement comparable with that of patients without amaurosis. The presence of intraoperative amaurosis was not associated with either macular hole closure or macular edema regression. PVEP revealed no significant changes in the wave latency or amplitude before and after surgery. CONCLUSION: Intraoperative amaurosis following sub-Tenon's block is commonly seen but does not predict a poor surgical prognosis. When a patient develops amaurosis during surgery, the surgeon should increase patient comfort through verbal communication rather than perform an additional intervention to help relieve the patient's anxiety.

Correlation between sub-Tenon's anesthesia and transient amaurosis during ophthalmic surgery.

PURPOSE: To verify the correlation between sub-Tenon's anesthesia and intraoperative visual loss in ophthalmic surgery. METHODS: Sixty-four patients underwent phacoemulsification combined pars plana vitrectomy under sub-Tenon's anesthesia. Participants were investigated about their light perception at several time points: before anesthesia, immediately after anesthesia, 10 min after anesthesia without any surgical intervention or microscope illumination, and after the whole surgery. Intraoperative amaurosis was determined as that a patient could not see any light from their operative eye. The incidence rate of amaurosis at different time points and among different anesthetists was analyzed. RESULTS: The rate of intraoperative amaurosis was 0%, 1.56%, 48.44%, and 95.31% at several time points, respectively: before anesthesia, immediately after anesthesia, 10 min after anesthesia without any surgical intervention or microscope light exposure during the interval, and immediately after the whole surgery, presenting a significantly time-dependent increase (P < 0.01). There was no correlation between the amaurosis and different diseases and anesthesiologists. The amaurosis was transient, and all operative eyes could perceive light on the first postoperative day. CONCLUSIONS: Sub-Tenon's anesthesia contributes to the intraoperative amaurosis during operation. Temporary interruption of optic nerve conduction by the anesthetic could be a credible explanation. The amaurosis is transient and reversible, requires no additional treatment, and should not be considered as a surgical complication.

Incidence and impact factors of intraoperative loss of light perception under sub-Tenon's anesthesia in patients with macular diseases.

PURPOSE: To investigate the incidence and impact factors of intraoperative loss of light perception (LP) under sub-Tenon's anesthesia in patients with macular diseases. METHODS: Eighty-five consecutive patients received standard phacoemulsification combined pars plana vitrectomy (PPV) under sub-Tenon's anesthesia. At several checkpoints during the surgery (the end of phacoemulsification, the end of vitrectomy, and the end of surgery), participants were interviewed about whether they had LP or not after removing the influence of contralateral eye and the photo-bleaching effect. In patients treated with retinal photocoagulation, visual experience on laser flashes was evaluated. RESULTS: Under routine draping, no patients reported loss of LP at all the checkpoints. When the contralateral eye was tightly covered, the rates of LP loss were 84.7%, 97.6%, and 87.1% at the end of phacoemulsification, the end of vitrectomy, and the end of surgery, respectively. When the photo-bleaching effect was also removed, the rates of LP loss were 61.2%, 82.4%, and 56.5% at each checkpoint, respectively, and there were 87.1% (74/85) of patients reporting visual loss in at least one checkpoint. In addition, 76.9% (50/65) of patients could not feel laser flashes during retinal photocoagulation. CONCLUSION: Intraoperative loss of LP under sub-Tenon's anesthesia was a relatively common and reversible event. The conduction block of optic nerve by anesthetic mainly contributed to the visual loss during surgery. Photo-bleaching effect also has some effect on the LP evaluation. Surgeons need to inform and counsel the patients about the intraoperative loss of LP, to prevent any sudden panic attacks in them.

Transfer Kernel Common Spatial Patterns for Motor Imagery Brain-Computer Interface Classification.

Motor-imagery-based brain-computer interfaces (BCIs) commonly use the common spatial pattern (CSP) as preprocessing step before classification. The CSP method is a supervised algorithm. Therefore a lot of time-consuming training data is needed to build the model. To address this issue, one promising approach is transfer learning, which generalizes a learning model can extract discriminative information from other subjects for target classification task. To this end, we propose a transfer kernel CSP (TKCSP) approach to learn a domain-invariant kernel by directly matching distributions of source subjects and target subjects. The dataset IVa of BCI Competition III is used to demonstrate the validity by our proposed methods. In the experiment, we compare the classification performance of the TKCSP against CSP, CSP for subject-to-subject transfer (CSP SJ-to-SJ), regularizing CSP (RCSP), stationary subspace CSP (ssCSP), multitask CSP (mtCSP), and the combined mtCSP and ssCSP (ss + mtCSP) method. The results indicate that the superior mean classification performance of TKCSP can achieve 81.14%, especially in case of source subjects with fewer number of training samples. Comprehensive experimental evidence on the dataset verifies the effectiveness and efficiency of the proposed TKCSP approach over several state-of-the-art methods.

[Protection and mechanism of shenqi compound for diabetic angiopathy model rats].

OBJECTIVE: To investigate the protective effect and mechanism of Shenqi Compound on diabetic angiopathy modeled rats. METHODS: Totally 18 SD rats were randomized into 3 groups, i.e., the normal control group, the diabetic mellitus (DM) group, and Shenqi Compound group, 6 in each group. The DM rat model was established by feeding high-fat diet (to induce hyperlipidemia) +intraperitoneal injection of small dose streptozotocin (STZ). Shenqi Compound was given to rats in the Shenqi Compound group at the daily dose of 2 g/kg. Equal volume of normal saline was given to rats in the model group and the normal control group by gastrogavage. All treatment was lasted for 12 weeks. Then 2-D and ultrasonic integrated backscatter technique were used to evaluate structural and functional changes of abdominal aorta in the progression of diabetic macroangiopathy. The fibrosis degree of the aorta vessel and myocardium capillaries were observed by using HE and Masson trichrome staining. The tension of the aortic vascular ring was determined. The transforming growth factor beta (TGF-beta) mRNA expression was detected by real time PCR (RT-PCR). The protein expression of TGF-beta, collagen I, collagen III, connective tissue growth factor (CTGF), and phosphorylation P38 MAPK were detected by Western blot. RESULTS: Compared with the normal control group, abdominal aortic systolic inner diameter, diastolic inner diameter, Peterson elastic modulus, stiffness index, and backscatter integral significantly increased; the rangeability of integral backscatter and the extension coefficient of cross section significantly decreased in the DM group (all P < 0.05). After 12 weeks aforesaid indices were obviously improved in the Shenqi Compound group (P < 0.05). Results of HE and Masson staining showed that the fibrosis degree of the aorta vessel and myocardium capillaries was obviously alleviated in rats of the Shenqi Compound group (P < 0.05). Results of the aortic vascular ring tension showed that acetylcholine induced vasodilatation and maximum diastolic percent were obviously elevated in the Shenqi Compound group (P < 0.05). Compared with the normal control group, the mRNA expression of TGF-beta, and the protein expression of TGF-beta, collagen I, and collagen III, and phosphorylation of P38 MAPK all significantly increased in the DM group (P < 0.05). Compared with the DM group, the mRNA expression of TGF-beta, and the protein expression of TGF-beta, collagen I, and collagen III, and phosphorylation of P38 MAPK all decreased (P < 0.05). CONCLUSIONS: Shenqi Compound could effectively improve the arterial function in diabetic marcoangiopathy and microvascular dysfunction. The mechanism might be due to the down-regulating the expression of TGF-beta, and further suppressing the phosphorylation of P38 MAPK, reducing the synthesis of collagen I and collagen III, therefore, ameliorating arterial and myocardial interstitial fibrosis.

Cardioprotective effect of mangiferin on left ventricular remodeling in rats.

The purpose of this study was to clarify the protective role of mangiferin on postinfarction myocardial remodeling and potential mechanisms. The myocardial infarction (MI) model was established by ligating the left anterior descending coronary artery. Cardiac function, myocardial apoptosis and fibrosis, serum tumor necrosis factor-α (TNF-α) and phosphorylated p38 mitogen-activated protein kinase (MAPK) were examined by echocardiography, histological staining, ELISA and Western blot, respectively. Mangiferin attenuated MI and prevented the development of intercellular fibrosis. Western blotting underscores that the p38 MAPK cascade plays an important role in the cardioprotective effect of mangiferin during MI. Inhibition of p38 MAPK significantly decreased serum TNF-α levels. Transferase-mediated uridine nick end labeling and Masson staining also showed that mangiferin reduced apoptosis and fibrosis in myocardium remodeling. Based on these results, we conclude that mangiferin has a therapeutic effect on post-MI left ventricular remodeling and improves cardiac function.