|A thicker-than-average choroid is characteristic of central serous chorioretinopathy. Photo: Mohammad Rafieetary, OD. Click image to enlarge.|
Loculation of fluid refers to the accumulation of liquid beyond the limit of saturation; it can be found in the posterior choroid of eyes with central serous chorioretinopathy (CSCR). Researchers based in Okinawa used multimodal imaging to examine the clinical factors related to loculation of fluid in CSCR patients, and they found that a thick choroid and thick sclera were independently associated with the presence of loculation of fluid.
The study classified 158 eyes into the loculation of fluid group (n=98) and a group without (n=60). Swept-source OCT determined the presence of loculation of fluid based on B-scan and en face images. The team also measured scleral thickness 6mm posterior to the scleral spur in four directions using anterior segment OCT.
The proportion of loculation of fluid in CSCR eyes was 62.0%. The fluid group was younger (50.2 vs. 55.1), had a higher male ratio (87.8% vs. 73.3%) and greater subfoveal choroidal thickness (SCT; 448.2µm vs. 325.9µm) than the non-fluid group.
All scleral thicknesses were significantly greater in the fluid group than in the non-fluid group at the superior (426.2μm vs. 395.1μm), temporal (445.7μm vs. 414.9μm), inferior (459.2μm vs. 428.8μm) and nasal (445.4μm vs. 414.3μm) points. The researchers noted loculation of fluid in 86.1% of cases with SCT greater than 403μm.
The study found no significant differences in spherical equivalent and axial length between the two groups.
“Our results showed that the abnormal accumulation of fluid that goes beyond the limit in CSCR eyes with loculation of fluid might be a manifestation of excessive fluid at least partially accumulated in the choroidal stroma and the suprachoroidal space,” the researchers wrote in their paper.
Because the CSCR cohort in the study mainly consisted of severe cases referred for treatment and did not include mild CSCR cases, they recommend further studies to evaluate a variety of CSCR cases.
“Future treatment strategies may target the sclera as a modifiable factor for refractory CSCR cases with loculation of fluid,” the researchers concluded.
Imanaga N, Terao N, Sawaguchi S, et al. Clinical factors related to loculation of fluid in central serous chorioretinopathy. Am J Ophthalmol. September 18, 2021. [Epub ahead of print].