Objective To determine the difference of global indices of retinal thickness at posterior pole in primary and suspected glaucoma. Methods Forty-five global indices of analysis on retinal thickness at posterior pole in every case, including 12 cases of primary open-angle glaucoma and 11 cases of suspected glaucoma were obtained by advanced retinal thickness analyzer. Every index was also compared. Results There were significant differences between primary and suspected glaucoma in foveal shape deviation (FSD), foveal corrected thickness deviation (FCTD), foveal fixation corrected thickness deviation (FFD), foveola thickness deviation (VTD), corrected foveola thickness deviation (CVTD), peri-foveal abnormally thin area (PFATN), posterior-pole pattern deviation (PPPD), and posterior-pole abnormally thin area (PPATN). Conclusion There are significant difference of morphologic indices of retinal thickness at posterior pole between primary and suspected glaucoma. (Chin J Ocul Fundus Dis, 2002, 18: 113-115)
Objective To prepare carboxymethyl-chitosan/hyaluronic acid/poly(vinyl alcohol) (CHP) blend membrane, evaluate its physicochemical properties and intraocular biocompatibil ity and to investigate its feasibil ity to be appl ied to glaucoma filtering surgery. Methods CHP blend membrane was prepared using solution casting method after blending carboxymethyl-chitosan, HA and poly(vinyl alcohol) in a proportion of 5 ∶ 4 ∶ 1 (M/M). Its water absorption rate, swell ing rate, permeabil ity, and mechanical properties were detected. Subconjunctival fibroblasts separated from subconjuncitival tissue of New Zealand white rabbits were cultured, and the cells at passage 4 were cultured on cell culture plate with or without the CHP blend membrane, serving as the experimental group and the control group, respectively. Effectof the CHP blend membrane on the subconjunctival fibroblasts was tested by MTT method 24, 48, and 72 hours after culture. Six New Zealand white rabbits were randomly divided into two groups (n=3 rabbits per group), and the CHP blend membrane and SK gel were implanted into the rabbits’ subconjunctival space and anterior chamber in the experimental group and the control group, respectively. Sl it lamp observation and binocular reaction record were conducted 1, 3, 5, 9, 11, 20, 30, 45, and 60 days after operation. Corneal tissue harvested from the experimental group was observed using scanning electron microscope 15 days after operation to study ophthalmic biocompatibil ity and biodegradabil ity. Results The water absorption rate and the swell ing rate of the CHP blend membrane was 83.8% ± 1.3% and 3.59 ± 0.50, respectively. The tensile strength of the dry and the wet CHP blend membrane was (20.59 ± 1.73) and (0.51 ± 0.13) MPa, respectively. The breaking elongation rate of the dry and the wet CHP blend membcane was 10.69% ± 1.16% and 53.15% ± 2.46%, respectively. The CHP blend membrane had good permeabil ity to NaCl and L-tyrosine. Absorbance (A) value of the experimental group 24, 48, and 72 hours after breeding was 0.207 ± 0.083, 0.174 ± 0.080, and 0.181 ± 0.048, respectively, while the A value of the control group was 0.284 ± 0.011, 0.272 ± 0.083, and 0.307 ± 0.056, respectively. Significant difference was evident between two groups (P lt; 0.05). In the experimental group, a small amount of floccus was exuded around the implanted membrane 1 day after operation; the floccus was absorbed on the third day, and there was no obvious inflammatory reaction occurring on the eleventh day. Most of the membrane degraded on the sixtieth day. Scanning electron microscope observation showed that the hexagonal morphology of the corneal endothel ial cells was intact, and no degradation particles adhered to the surface. In the control group, the implantation of SK gel into anterior chamber was unsuccessful because the SK gel was quite soft and easily broken. In the experimental group, mild hyperemia emerged around the implanted membrane 1 day after the subconjunctival implantation of the membrane, and it became normal on the ninth day. No corneal edema and inflammatory reaction of anterior chamber occurred till the sixtieth day. The results in the control group and the experiment group were similar. Conclusion Due to its good physicochemical properties and biocompatibil ity, the CHP blend membrane has potential appl ications in glaucomafiltering surgery.
ObjectiveTo investigate the relationship between the changes in preoperative serum creatinine (Cr), myoglobin (Mb), alanine aminotransferase (ALT) and postoperative fibrinogen (Fib), C- reactive protein (CRP) expression levels and postoperative hypoxemia in patients with aortic dissection aneurysm (ADA), and construct a predictive model. Additionally, the study explores the role of transpulmonary pressure-guided positive end expiratory pressure (PEEP) in improving postoperative hypoxemia. MethodsA retrospective analysis was conducted on the clinical data of ADA patients admitted to Tianjin Chest Hospital from April 2021 to August 2023. Patients were divided into a hypoxemia group [partial pressure of oxygen/fraction of inspiration oxygen (PaO2/FiO2) ≤200 mm Hg] and a non-hypoxemia group (PaO2/FiO2 >200 mm Hg) based on whether they developed postoperative hypoxemia. Univariate and multivariate regression analyses were used to identify risk factors for postoperative hypoxemia in ADA patients and to construct a predictive model for postoperative hypoxemia. The receiver operating characteristic (ROC) curve was plotted, and the Hosmer-Lemeshow goodness-of-fit test was used to evaluate the predictive value of the model. Furthermore, the impact of different ventilation modes on the improvement of postoperative hypoxemia was analyzed. From April 2021 to August 2023, 16 ADA patients with postoperative hypoxemia who received conventional mechanical ventilation were included in the control group. From September 2023 to December 2024, 28 ADA patients with postoperative hypoxemia who received transpulmonary pressure-guided PEEP were included in the experimental group. ICU stay duration, mechanical ventilation duration, hospital mortality rate, and respiratory and circulatory parameters were analyzed to evaluate the effect of transpulmonary pressure-guided PEEP on patients with postoperative hypoxemia after acute aortic dissection. ResultsA total of 98 ADA patients were included, of which 79 (80.61%) were males and 19 (19.39%) were females. Their ages ranged from 32 to 79 years, with an average age of (49.4±11.2) years. Sixteen (16.3%) patients developed postoperative hypoxemia. Body mass index (BMI), smoking history, cardiopulmonary bypass (CPB) duration, preoperative serum Cr, Mb, ALT, and postoperative Fib and CRP showed a certain correlation with postoperative hypoxemia in ADA patients (P<0.05). There was no statistical difference in other baseline data between the two groups (P>0.05). Logistic regression analysis results indicated that BMI [OR=1.613, 95%CI (1.260, 2.065)] and preoperative Mb [OR=2.344, 95%CI (1.048, 5.246)], ALT [OR=1.012, 95%CI (1.000, 1.024)], Cr [OR=1.752, 95%CI (1.045, 2.940)], postoperative Fib [OR=1.165, 95%CI (1.080, 1.258)] and intraoperative CPB time [OR=1.433, 95%CI (1.017, 2.020)] were influencing factors of postoperative hypoxemia in ADA patients (P<0.05). Based on this, a prediction model for postoperative hypoxemia in ADA patients was established. The area under the curve corresponding to the optimal critical point was 0.837 [95%CI (0.799, 0.875)], with a sensitivity of 87.5% and a specificity of 79.3%. The Hosmer-Lemeshow goodness of fit test showed P=0.536. Before treatment, there were no statistical differences in respiratory and circulatory parameters between the control group and the experimental group (P>0.05). After treatment, the levels of PEEP, PaO2/FiO2, end-expiratory esophageal pressure, and end-inspiratory transpulmonary pressure in the experimental group were higher than those in the control group (P<0.05). The duration of mechanical ventilation and ICU stay in the experimental group were shorter than those in the control group (P<0.05), while there was no statistical difference in mortality between the two groups (P=0.626). ConclusionThe hypoxia prediction model based on preoperative Cr, Mb, ALT and postoperative Fib levels, combined with transpulmonary pressure-guided PEEP optimization, provides a scientific basis for the precise management of postoperative hypoxemia in ADA. This approach not only improves the predictive ability of hypoxemia risk but also significantly improves the postoperative oxygenation status of patients through personalized mechanical ventilation strategies, providing new insights into the management of postoperative complications.