Optical coherence tomography angiography in central serous chorioretinopathy: The current clinical role and future perspectives

Quantitative optical coherence tomography angiography assessments in the fellow eyes of those with central serous chorioretinopathy

BACKGROUND

To analyze the vessel density (VD) of the retina and choriocapillaris (CC) layer and the structure of the foveal avascular zone (FAZ) in the fellow eyes of central serous chorioretinopathy (CSC) patients by using optical coherence tomography angiography (OCTA).

METHODS

This was a case-control study. Unilateral CSC patients and age-matched healthy subjects were recruited from the Affiliated Eye Hospital of Wenzhou Medical University between July 2016 and July 2021. All eyes were divided into three groups: acute CSC (aCSC), chronic CSC (cCSC), and healthy controls. Both aCSC and cCSC were again divided into two subgroups: the affected eyes and the fellow eyes. In this study, all parameters of VD and FAZ were measured by self-software of OCTA.

RESULTS

A total of 231 eyes of 137 subjects were included, with 47 aCSC patients, 47 cCSC patients, and 43 healthy controls. In the fellow eyes of CSC, the retinal VD was significantly lower (all P < 0.05), and the FAZ was significantly larger (all P < 0.05) in the cCSC group than in healthy controls, while no difference was detected in the CC layer. There was no significant difference between the aCSC group and healthy controls in all OCTA parameters. In the affected eyes of CSC, the superficial retinal vessel density (SRVD) was significantly higher (all P < 0.05) in healthy controls than in the aCSC and cCSC groups, while the deep retinal vessel density (DRVD) was significantly lower (all P < 0.05) and the FAZ was larger (all P < 0.05) in the cCSC group than in the aCSC group and healthy controls. A liner regression equation was established: Y (BCVA, best corrected visual acuity) = 3.692-0.036✱X1 (DRVD-Fovea)-0.031✱X2 (FD-300, vessel density around the 300 μm width of the FAZ), R2 = 0.427.

CONCLUSION

Based on OCTA measurements, this study revealed that the retinal microvascular network was impaired even in the fellow eyes of those with cCSC, which should arouse attention to the observation of unilateral CSC.

Central serous chorioretinopathy: A review

Central serous chorioretinopathy (CSC) is the fourth most common non-surgical retinopathy associated with fluid leakage. The pathogenesis is not yet completely understood, but changes in the choroid, sclera and RPE have been described associated with venous congestion of choroidal outflow. CSC can be categorised into acute, chronic, and recurrent subtypes with recent classifications of simple and complex based on the area of RPE change seen on fundus autofluorescence. A multimodal imaging approach is helpful in the diagnosis and management of CSC and secondary complications such as type 1 neovascularisation. Although spontaneous resolution with relatively good visual outcomes is common, treatment should be considered in patients with persistent or recurrent SRF. Treatment options include laser, systemic medications, intravitreal therapy, and surgery. Of these, argon laser for focal extramacular fluid leaks and photodynamic therapy of leakage identified by indocyanine-green angiography currently have the greatest supportive evidence.

The Temporal Topography of Central Serous Chorioretinopathy in the Chinchilla Rabbits Induced by Intravenous Injection of Adrenaline: An in vivo Study

Purpose

To explore the temporal topography of the chorioretinopathy in an animal model of central serous chorioretinopathy (CSC) induced by intravenous injection of adrenalin in the Chinchilla rabbits.

Methods

Ten Chinchilla rabbits received a daily intravenous injection of adrenaline at 0.04 mg/kg for 8 weeks. Fluorescence fundus angiography (FFA) and electroretinogram (ERG) were performed every week afterwards to see whether there was fluorescence leakage in the fundus and to evaluate the retinal function. Indocyanine green angiography (ICGA) and optical coherence tomography (OCT) were also conducted to detect the change of choroidal vessels. Finally, the eyes of the rabbits were enucleated to make the retinal sections for histological examination with hematoxylin–eosin (HE) staining.

Results

Within 8 weeks of the adrenalin administration, 7 out of the 10 rabbits showed different degrees of fluorescence leakage on FFA. The leakage was more obvious during 2–3 weeks after the adrenalin administration. With the progress of disease, the leakage subsided gradually and a scar-like lesion formed. ICGA revealed the local choroidal ischemia and the dilated choroidal vessels. An obvious detachment of retina and an increased thickness of the choroid were found on OCT, which was most obvious 2 weeks after the adrenalin administration (P<0.01). ERG revealed no obvious decline of the b-wave amplitude before and after the adrenalin administration (P>0.05). A circumscribed retinal detachment, the depigmentation of retinal pigment epithelium and enlarged choroidal vessels were shown by the histological examination.

Conclusion

The temporal topography of the chorioretinopathy in the Chinchilla rabbits by intravenous injection of adrenaline somewhat mimicked that of the human CSC, which could enhance its application in the exploration for the pathogenesis and the therapeutic measures for human CSC.

Intima-Media Thickness Measurements of the Common Carotid Artery in Patients with Central Serous Chorioretinopathy: A Case-Control Study

Purpose

To evaluate the intima-media thickness (IMT) of the left and right common carotid arteries (CCA) as an indicator of subclinical atherosclerosis in patients with central serous chorioretinopathy (CSCR).

Methods

This was a case-control study involving patients with CSCR and a matched healthy control group. The mean and difference of the left and right CCA IMT were determined and compared between the two groups using carotid duplex high-resolution B-mode ultrasound equipment.

Results

The study enrolled 32 CSCR patients (68.8% female, mean age 38.22 ± 5.42 years) and 32 controls (65.6% female, mean age 39.56 ± 5.33 years). The difference in common carotid IMT between the right and left sides was significantly greater in the CSCR group than in the control group (p < 0.001). Additionally, according to logistic regression analysis, patients with CSCR had a greater chance of having differences in IMT between the two sides when compared to the control group (OR: 1.29, 95% CI: 1.09–1.52).

Conclusion

Our findings indicated that in the CSCR group, the difference between the right and left sides of CCA IMT was significantly greater than in the control group.