Macular edema is an important cause of visual impairment in many eye diseases such as diabetic retinopathy, retinal vein occlusion and uveitis. Optical coherence tomography (OCT) provides high-resolution image of retinal microstructures in a non-contact and rapid manner, which greatly improves the ability of diagnosis and follow-up to macular edema patients. OCT has been widely used in the clinical detection of patients with macular edema. No matter what the cause of macular edema is, it can be observed in OCT images that there are spot-like deposits with strong reflection signals in the retina, which are mostly distributed discretely or partially convergent, and are called hyperreflective foci. At present, the nature or source of hyperreflective foci is not clear, however, may involve the destruction of the blood retina barrier, retinal inflammatory reaction, neurocellular degeneration, and so on. These mechanisms are also the key physiological mechanisms in the development of macular edema. The clinical research on hyperreflective foci provides a new direction for understanding the pathogenesis of macular edema and predicting the prognosis of macular edema. The distribution and quantity characteristics of hyperreflective foci may be an important biological marker to predict the prognosis of macular edema.nosis of macular edema. foci provides a new direction for understanding the pathogenesis of macular edema and predicting the prognosis of macular edema. The distribution and quantity characteristics of HRF may be an important biological marker to predict the prognosis of macular edema.
COVID-19 associated fundus lesions are mostly vascular occlusion or inflammatory changes. The affected vessels include both retinal macrovessels and microvessels, and the inflammatory changes are mainly autoimmune lesions. Clinically, the different lesions present as various fundus diseases, with varying degrees of impact on visual function. The mechanism of these lesions is considered to be related to direct injury of SARS-CoV-2, abnormal coagulation or inflammatory response caused by SARS-CoV-2. Awareness of fundus lesions associated to COVID-19 is helpful to figure out the pathophysiological mechanism of COVID-19 and promote in-depth studies for a deeper and complete understanding of the occurrence and full impact of COVID-19, emphasizing the importance of early prevention and control of the disease, and highlighting the significance of early intervention of the fundus diseases caused by COVID-19.
Noninfectious uveitis refers to a category of inflammatory diseases involving the uvea, with the exception of infectious factors or masquerade syndrome. The diagnosis and follow-up of noninfectious uveitis that involving retina or choroid require fundus imaging techniques. Fundus autofluorescence is a noninvasive imaging technique. Compared with fundus colorized photography, fundus fluorescein angiography and indocyanine green angiography, fundus autofluorescence indicates the functional status of retinal pigment epithelium and photoreceptor cells in a better way, thus playing a role in the pathophysiological mechanisms investigating, early diagnosis, disease progression monitoring and prognosis estimating of noninfectious uveitis, such as Vogt-Koyanagi-Harada disease, Behçet disease, multifocal choroiditis, punctate inner choroidopathy, birdshot chorioretinopathy, multiple evanescent white dot syndrome, acute zonal occult outer retinopathy, acute posterior multifocal placoid pigment epitheliopathy and serpiginous choroiditis.
Noninfectious uveitis refers to a category of inflammatory diseases involving the uvea, vitreous, optic disk and retina, with the exception of infectious factors or masquerade syndrome. These kind of blinding diseases are frequently recurrent, and the diagnosis and follow-up require fundus imaging techniques. OCT angiography (OCTA) is a rapid, noninvasive and quantifiable blood flow imaging modality that provides a depiction of the microvasculature morphology of the retinal and choroidal through different segmentation and detects the abnormal blood perfusion as well as the neovascularization. OCTA plays an important role in the diagnosis, assessment and follow-up for anterior uveitis, posterior uveitis and pan-uveitis such as Vogt-Koyanagi-Harada disease, Behçet’s disease, ocular sarcoidosis, birdshot chorioretinopathy, serpiginous choroiditis, multifocal choroiditis, punctate inner choroidopathy, acute zonal occult outer retinopathy, acute posterior multifocal placoid pigment epitheliopathy, multiple evanescent white dot syndrome, and also provides clue about their pathophysiologic mechanisms.
ObjectiveTo observe the changes of blood flow density and perfusion density in the macula of non-diabetic peritoneal dialysis (PD) patients, and their correlation with blood pressure, total protein, albumin, prealbumin, serum creatinine, urea, and high-sensitivity C-reactive protein were preliminarily analyzed.MethodsA single-center, cross-sectional, clinical observational study. From January to December 2018, 63 eyes of 63 non-diabetic patients (non-diabetic PD group) and 75 eyes of normal healthy people (the normal control group) who underwent PD treatment at the PD Center of Peking University First Hospital were included in the study. All were monocular into the group. Among the 63 patients in the non-diabetic PD group, 24 were males and 39 were females. The duration of PD was 7 to 185 months, with the average duration of 67.87±48.36 months. There were 75 healthy persons in the normal control group. There was no significant difference in age (t=－0.558), sex ratio (χ2=0.492), axial length (t=－1.197), and BCVA between the two groups (P＞0.05). OCT angiography was used to scan the macular area of 3 mm×3 mm and 6 mm×6 mm in the subject’s right eye. The blood flow density and perfusion density of superficial retinal capillaries in the macular area, as well as the area, circumference, and morphological index of the foveal avascular zone (FAZ) were measured. The blood flow density and perfusion density at different locations in the macular area of the two groups of eyes were compared by independent sample t test. The blood pressure, total protein, albumin, prealbumin, serum creatinine, urea, and high-sensitivity C-reactive protein was performed by Pearson correlation analysis.ResultsCompared with the healthy control group, the blood flow density and perfusion density of superficial retinal capillaries in the macular area of the non-diabetic PD group decreased in different scanning ranges with the macular vessel 3×3 center (t=－2.409), the macular vessel 3×3 macular (t=－2.423), macular vessel 3×3 intact (t=－2.759), macular vessel 6×6 intact (t=－1.882), macular vessel 6×6 outer layer (t=－2.188), macular perfusion 3×3 center (t=－1.990), macular perfusion 3×3 complete (t=－2.719), macular perfusion 6×6 complete (t=－2.113), and macular perfusion 6×6 outer layer (t=－2.205). The difference was statistically significant (P＜0.05). The comparison of the macular FAZ area of the two groups of eyes was statistically significant (t=1.985, P＜0.05). Correlation analysis showed that 3×3 macular blood vessels were intact and mean arterial pressure was positively correlated (r=0.256, P=0.043). The macular blood vessels were 3×3 intact, macular perfusion was 3×3 intact, and macular blood was 6×6 intact, which the pre-white protein was positively correlated with (r=0.468, 0.362, 0.333; P＜0.001, P=0.004, 0.008). The macular vessel 3×3 was intact, the macular perfusion 6×6 was intact, which the hypersensitive C-reactive protein was negatively correlated with (r=－0.370, －0.287, P=0.005, 0.030).ConclusionThe superficial retinal blood flow density and perfusion density in the macular area of non-diabetic PD patients are lower than those of normal healthy people.
ObjectiveTo observe the features of temporal macular thinning and its value for the diagnosis of Alport syndrome (AS) in young patients.MethodsEighty-one young patients with AS (81 eyes) from Peking University First Hospital during January 2016 and July 2017 were included in this study. There were 67 males (67 eyes) and 14 females (14 eyes),the aged from 3 to 17 years, with the mean age of 9.6 years. Among 81 patients (81 eyes), there were 64 patients with X-linked AS (XLAS, including 53 males and 11 females), 17 patients with autosomal recessive AS (ARAS, including 14 males and 3 females). One hundred healthy subjects aged 4 to 17 years were included as controls. Clinical data were retrospectively evaluated, including visual acuity, slit-lamp microscopy, dilated fundus photography, and OCT. Retinal thickness was measured with an OCT scan and the temporal thinning index (TTI) was calculated as stated in a previous study. The TTI values of each group was compared by One-way ANOVA or independent sample t test. The receiver operating characteristic (ROC) curve was used to evaluate the diagnostic effectiveness for AS.ResultsThe TTI of the control group, XLAS and ARAS patients were 6.46±1.58, 10.93±3.77, 12.14±4.05, respectively. Compared with the control group, the TTI value of males were larger in the XLAS and ARAS group (F=45.056, P＜0.001), the TTI value of females were larger in the ARAS group (F=26.541, P＜0.001). The difference of TTI value in females was significant between the XLAS and ARAS groups (F=26.541, P＜0.001). In males, the area under the ROC curve was 0.896 (95%CI 0.837−0.955, P＜0.001). The optimal cutoff value of the TTI was determined as 9.47, with a sensitivity of 73.1% and a specificity of 100%.ConclusionsTTI is a common ocular finding in young patients with AS. In males, a TTI ＞ 9.47 may differentiate AS from normal males.