Foveal thickness and vascular variables in adolescents born moderate-to-late preterm
Titus Ovik1, Alexandra Lind1, Zoran Popovic1
1Department of Clinical Neuroscience, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Insights
Adolescents born moderate-to-late preterm (MLP) show altered foveal avascular zone (FAZ) area and central foveal thickness (CFT) compared to full-term controls. These findings suggest similar parafoveal changes as seen in very preterm infants.
Area of Science:
- Ophthalmology
- Neonatology
- Developmental Biology
Background:
- Infants born very preterm face increased risks of ocular abnormalities, including changes in foveal morphology.
- The long-term ocular effects of moderate-to-late preterm (MLP) birth (32 0/7–36 6/7 weeks gestation) remain largely unknown.
Purpose of the Study:
- To investigate the foveal avascular zone (FAZ) area, vascular density (VD), central foveal thickness (CFT), and ganglion cell layer (GCL++) thickness in adolescents born MLP without a history of retinopathy of prematurity.
- To compare these ocular parameters in MLP adolescents with those of healthy full-term controls.
Main Methods:
- A prospective, population-based cohort study involving 50 adolescents born MLP and 49 healthy full-term controls (mean age ~16.6 years).
- Optical coherence tomography (OCT) and OCT angiography (OCT-A) were used to assess FAZ area, VD, CFT, and GCL++.
- FAZ and VD were adjusted for ocular magnification; CFT and GCL++ were directly measured.
Main Results:
- Adolescents born MLP exhibited a statistically significant smaller FAZ area (0.22 mm² vs. 0.28 mm²) and increased CFT (198.1 μm vs. 187.1 μm) compared to controls.
- Strong negative correlations were observed between FAZ area and both CFT (r = -0.773) and GCL++ (r = -0.924) in the MLP group.
- No significant differences in vascular density (VD) were found between the groups.
Conclusions:
- Adolescents born moderate-to-late preterm demonstrate smaller FAZ areas and increased CFT relative to full-term controls.
- These parafoveal alterations in MLP adolescents mirror those observed in individuals born extremely or very preterm.
- The findings highlight potential long-term ocular developmental impacts of moderate-to-late preterm birth.
Purpose:
It is well established that children born very preterm are at increased risk for ocular abnormalities including altered foveal morphology. However, little is known about how children born moderate-to-late preterm (MLP), gestational age 32 + 0-36 + 6 weeks, are affected later in life. This study investigates foveal avascular zone (FAZ) area, vascular density (VD), central foveal thickness (CFT) and ganglion cell layer thickness (GCL++) of adolescents born MLP without history of retinopathy of prematurity and compare the results with full-term controls.
Methods:
In a prospective population-based cohort study, 50 adolescents (26 girls; mean age 16.5 years) born MLP were examined with optical coherence tomography (OCT) and OCT angiography (OCT-A). FAZ and VD were obtained from OCT-A scans and adjusted for ocular magnification. CFT and GCL++ were obtained from the OCT scans. The results from the MLP individuals were compared with the results from 49 healthy full-term controls (29 girls; mean age 16.7 years).
Results:
The results showed statistically significant differences in FAZ area (0.22 vs 0.28 mm2; p = 0.0032) and CFT (198.1 vs 187.1 μm; p = 0.0010) between the MLP group and controls. Strong correlations between FAZ area and CFT (r = -0.773, p < 0.0001) and GCL++ (r = -0.924, p < 0.0001) were found in the MLP group. There were no differences in VD.
Conclusions:
Our results show that adolescents born MLP have a smaller FAZ area and an increased CFT compared with full-term controls. These results indicate that adolescents born MLP have similar parafoveal changes as children born extreme or very preterm.
