Objective To review the distribution and shifting trends of cultured bacteria from the aqueous humor and the vitreous body. Methods A retrospective analysis on distribution of Gram′s stain, the distribution and change of isolates was performed in 522 specimens (aqueous humor,261 and vitreous body,261) of patients with suspected endophthalmitis during a 10-year period (1989-1998). Results The positive cultures were 119 (aqueous humor,44 and vitreous body,75) of 522 specimens. The average positive rate was 22.8%. Gram-positive cocci constituting 45.4%(54) of total isolates followed by Gram-negative bacilli,34.5%(41);Gram-positive bacilli, 20.2%(24). In the positive bacterial cultures, enterobacteriaceae was the most common isolate, 18.5%, and the next was micrococcus, 16.0%; coagulase-negative staphylococcus,12.6%; and pseudomonas,10.9%.Comparing the data from 1989 through 1993 with the data from 1994 through 1998, the frequency of Gram-positive cocci had no significant change, while the frequency of Gram-positive bacilli was decreased and the percentage of Gram′s-negative bacilli was increased. Conclusions Gram-positive cocci and Gram-negative bacilli are the predominant pathogens of bacterial endophthalmitis. The percentage of Gram′s-negative bacilli has increased for 5 years. It is very important to comprehend the distribution and shifting trends of these pathogenic bacteria for diagnosis, prevention and treatment of bacterial endophthalmitis. (Chin J Ocul Fundus Dis, 2002, 18: 104-105)
ObjectiveTo study the changes the changes of cytokine expression the aqueous humor of patients with macular edema secondary to branch retinal vein occlusion (BRVO-ME) before and after intravitreal ranibizumab (IVR). MethodsA prospective clinical study. From June 2018 to June 2021, 31 eyes of 31 patients with non-ischemic BRVO-ME diagnosed by ophthalmic examination in Department of Ophthalmology, Beijing Hepingli Hospital were included in the study. Among them, 15 males had 15 eyes, and 16 females had 16 eyes. Age was 70 (65, 72) years; the course of disease was 10 (9, 15) days. All of them were first-time patients. All eyes were treated with IVR once a month for 3 consecutive months. At the end of each IVR treatment, 0.1 ml aqueous humor was extracted immediately. The concentrations of vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in aqueous humor were detected by flow cytometry. The concentrations of cytokines in aqueous humor before and after treatment were compared by Kruskal-Wallis or Wilcoxon signed-rank test. Spearman correlation analysis was performed on the correlation between VEGF and MCP-1 expression level in aqueous humor before treatment. ResultsThe concentrations of VEGF and ICAM-1 in aqueous humor were significantly lower at 1 month after treatment compared with that before treatment, and at 2 months after treatment compared with that at 1 month after treatment (Z=4.03, 3.25, 2.50, 3.48; P＜0.05); the concentrations of IL-6 and VCAM-1 increased and the concentration of MCP-1 decreased, but there was no significant difference (Z=－0.21, 1.42, 0.86, －0.53, 0.92, －1.57; P＞0.05). Spearman correlation analysis showed that there was a strong positive correlation between VEGF and MCP-1 in aqueous humor before treatment (r=0.78, P＜0.001). ConclusionThe concentrations of VEGF and ICAM-1 in aqueous humor significantly decrease after IVR treatment in BRVO-ME; the concentrations of IL-6, MCP-1 and VCAM-1 do not obviously change.
ObjectiveTo study the changes and correlation of cytokines in aqueous humor before and after intravitreal injection of conbercept (IVC) treatment in patients with proliferative diabetic retinopathy (PDR).MethodsA prospective clinical study. From March to December 2019, 36 patients (42 eyes) of PDR patients treated with IVC combined with pars plana vitrectomy (PPV) (the observation group) and 27 patients (31 eyes) underwent cataract surgery in the same period (control group) in Department of Ophthalmology of the First Affiliated Hospital of Guangzhou University of Chinese Medicine were included in this study. Before PPV 5-7 days, IVC treatment was performed, and the aqueous humor were extracted during IVC and second-stage PPV in the observation group. The aqueous humor was extracted during cataract surgery in the control group. Luminex assay was used to detect VEGF-A, placental growth factor (PLGF), platelet-derived growth factor-AA (PDGF-AA), platelet-derived growth factor-BB (PDGF-BB), angiopoietin-like protein 4 (ANGPTL4), IL-6, IL-8, IL-1β, monocyte chemoattractant protein-1 (MCP-1), intercellular adhesion molecule-1 (ICAM-1), tumor necrosis factor-α (TNF-α) cytokine expression. For normally distributed data, the independent sample t test was used for comparison between two independent samples; for non-normally distributed data, the Wilcoxon rank sum test was used for comparison between two independent samples. The correlation analysis used Spearman rank correlation test.ResultsBefore IVC treatment, the concentrations of VEGF-A, PLGF, PDGF-AA, ANGPTL4, IL-6, IL-8, MCP-1 and ICAM-1 in the aqueous humor of PDR patients were significantly higher than those in the control group (P＜0.05). After IVC treatment, the concentration of VEGF-A in the aqueous humor was significantly lower than that before treatment, and the concentrations of ANGPTL4 and IL-8 were significantly higher than those before treatment (P＜0.05). There were no significant differences in the concentrations of PLGF, PDGF-AA, PDGF-BB, IL-6, IL-1β, MCP-1, ICAM-1 and TNF-α before and after IVC treatment (P＞0.05). Before IVC treatment, the concentration of VEGF-A was positively correlated with PLGF, PDGF-AA, PDGF-BB, ANGPTL4, IL-6, IL-8, MCP-1 and TNF-α (P＜0.05).ConclusionsIVC treatment can reduce the concentration of VEGF-A and increase the concentrations of ANGPTL4 and IL-8 in aqueous humor in PDR patients before PPV.
The fundus lesions caused by high myopia (HM) often lead to irreversible visual impairment or even blindness. However, the pathogenesis of HM and its fundus lesions is still unclear, the intraocular fluid detection technology of micro samples has brought new prospects for the early diagnosis, monitoring and intervention of the fundus lesions. The molecules associated with HM are various and functionally diverse, intermolecular interactions are staggered and the specific mechanism is complex. With the development of intraocular fluid detection technology, while gradually revealing the role of each molecule in the pathogenesis of HM, it is expected to successfully assist clinical work in the future, providing outpost markers for the progress of myopia and targets for early intervention, or providing a new therapy choice for HM fundus lesions at the molecular level targeting pathogenesis, which is expected to provide more accurate and effective treatment for HM patients in the future.
At present, there are few in vivo experimental studies on anterior chamber flow field, and the relevant technologies are not mature. This study explores the experimental method and key techniques of particle image velocimetry (PIV) for the in vivo measurement of anterior chamber flow field with slow flow velocity in the rabbit with acute intraocular hypertension. The experimental process can be divided into three parts: model construction of rabbit eye with acute intraocular hypertension, in vivo eyeball preparation, and PIV setup. The following key techniques were mainly investigated: the optimal injection strategy of fluorescent particles and the correction strategy for image acquisition errors caused by the effects of image refraction and respiration. The results showed that the best injection method was that 15 μL of fluorescent particles solution was slowly injected into the anterior chamber through the lower part of iris and then the rabbit was released and waited for 13 h. In this way particles were completely distributed in the anterior chamber with the help of the aqueous humor circulation, and then in vivo PIV experiment could be performed. The eyeball should be covered with a square flume filled with ultrasonic coupling gel for the sake of imaging during the experiment. The Maximal Information Coefficient algorithm could be applied to correct the measured results before post-processing calculation. The results indicated that feasible injection strategy of fluorescent particles and the correction strategy for image acquisition are critical to obtain nice experiment effects for the in vivo PIV measurement of anterior chamber flow field in the rabbit with acute intraocular hypertension.
There are many types of fundus diseases and their causes are complex. They can be caused by metabolic factors or inflammatory factors. Fundus examination and imaging examination tools are the main methods for diagnosing fundus diseases. However, in terms of determining the cause and early diagnosis, if the intraocular fluid detection technology can be reasonably combined, the advantages will be greater. Intraocular fluid is the general term for fluid in the eyeball, including aqueous humor, vitreous humor, etc. The molecular components that can be tested include DNA, RNA, antigens, antibodies, and cytokines. With the advancement of molecular testing technology and equipment, intraocular fluid testing as an evidence-based method has gradually been incorporated into the consensus and guidelines of more fundus disease experts, and is mainly used for infectious fundus diseases and camouflage syndromes. Reasonable use of intraocular fluid testing can help improve the personalized diagnosis and treatment of fundus diseases and reduce unnecessary drug overuse. However, it is worth noting that intraocular fluid detection is only one of many tools and cannot replace other examinations and clinical experience. Excessive intraocular fluid testing not only increases the risk of clinical infections because of invasiveness, but also increases the burden on patients.
ObjectiveTo analyze the sensitivity and specificity of polymerase chain reaction (PCR) tests in the detection of cytomegalovirus (CMV) in the diagnosis of patients with acquired immune deficiency syndrome (AIDS), using aqueous humor samples. Methods25 AIDS patients (including 21 men and 4 women) were studied. The age of the patients varied from 24 to 59 years, with an average of (39.2±9.3) years. The CD4+ T cell count was from 1 to 523 cells/μl, with a medium of 40 cells/μl. They were infected with human immunodeficiency virus(HIV)for a period from 15 days to 9 years with a median of 10 months. They were divided into three groups according to the fundus and treatment, including untreated cytomegalovirus retinitis (CMVR), treated CMVR and control group. There were 10 patients without anti-CMV treatment and 7 patients treated previously with foscarnet or ganciclovir whose eyes were diagnosed CMVR. Control group has 8 patients who had normal fundus or minor retinopathy excluded from CMVR. Approximately 100 μl of aqueous humor was obtained by anterior-chamber paracentesis and PCR was performed in all cases. ResultsThere were CMV DNA in 9 of 10 eyes with untreated CMVR (90.0% sensitivity). Of 7 specimens from eyes with treated CMVR, 3 were CMV PCR positive (42.9% sensitivity). All 8 samples of the control group were negative for CMV DNA, indicating the clinical specificity of our PCR was greater than 99.9% for CMVR. The anterior chamber paracentesis did not cause any complications in our patients except for a patient with subconjunctival hemorrhage. ConclusionsThe assay had an estimated sensitivity of 90.0% in detecting untreated CMVR and a sensitivity of 42.9% in detecting CMVR that had been treated. The specificity of this assay was greater than 99.9%.