# En-Face Optical Coherence Tomography Angiography for Longitudinal Monitoring of Retinal Injury
## 3 Results
The height of the lesions shows minimal change \(121\pm 10\)\(\upmu\)m to \(131\pm 10\)\(\upmu\)m; therefore, the inner layers' integrity remains continuous. The CNV lesion show lesion dynamics with a clear transition into chronic inflammation. At day 3, all parameters are showing expansion. The lesion growth continues, and peaks around day 7. The edemas at day 7 mark the maximal vertical expansion of the lesions (Figure 4). While eventually as the swelling and edema volume subsides, only the height of the lesions returns to baseline. All other layers show clear lateral expansion of the lesion border from the first timepoint. Table 1 lists the measurements and variance analysis for each condition. The variance measured as standard deviation was predictably higher for CNV than acute injury treatment (124 \(\upmu\)m vs. 21 \(\upmu\)m), so \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & & & & Acute injury & & & & \\ \hline
**Day** & **ONL** & **CV** & **RPE** & **CV** & **Height** & **CV** & **PR** & **CV** \\ \hline
1 & 128.31 & 0.10 & 136.59 & 0.16 & 121.39 & 0.06 & 129.71 & 0.08 \\
3 & 110.90 & 0.22 & 196.09 & 0.23 & 131.55 & 0.08 & 78.07 & 0.18 \\
7 & 87.86 & 0.36 & 156.98 & 0.19 & 125.08 & 0.10 & 60.96 & 0.20 \\
14 & 94.38 & 0.32 & 146.75 & 0.31 & 123.95 & 0.11 & 64.52 & 0.25 \\
21 & 94.50 & 0.28 & 137.17 & 0.33 & 121.55 & 0.08 & 69.13 & 0.24 \\ \hline  & & & & & CNV & & & \\ \hline
**Day** & **ONL** & **CV** & **RPE** & **CV** & **Height** & **CV** & **PR** & **CV** \\ \hline
1 & 408.75 & 0.24 & 345.66 & 0.50 & 170.38 & 0.19 & 276.72 & 0.43 \\
3 & 418.96 & 0.24 & 428.85 & 0.13 & 204.83 & 0.19 & 278.93 & 0.25 \\
7 & 566.08 & 0.34 & 566.49 & 0.32 & 246.35 & 0.32 & 401.73 & 0.50 \\
14 & 457.69 & 0.39 & 520.06 & 0.30 & 197.74 & 0.29 & 314.71 & 0.49 \\
21 & 433.87 & 0.43 & 528.33 & 0.37 & 178.06 & 0.26 & 342.27 & 0.52 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Table of average lesions dimensions, measurement in \(\upmu\)m, as the lesions change over time. The Coefficient of Variation (CV) is standard deviation normalized by the mean, \(\sigma\)/\(\upmu\), is used to compare the measurement consistency. The Acute injury measurements show that the lesions are substantially smaller at day 1, 128 \(\upmu\)m compared to 408 \(\upmu\)m. At 21 days, acute injury measurements show a decrease while CNV has expanded. Figure 4: Lesion dynamics imaged by OCT over time (1 h-21 days) shows the progression of two exemplars of acute injury (**a–f**) and CNV lesions (**i–n**). The larger lesions and RPE (Retinal Pigment Epithelial) disruptions in CNV differ substantially from the subthreshold in both magnitude and temporal characteristics. Females developed more severe CNV at all time points; however, all measured trends of the pathology followed the same time course. Coefficient of Variation (CV) was used to ensure consistency in comparisons. When compared, the CV of 0.19 acute injury and 0.33 CNV indicates that both sample populations were internally consistent. When only considering inter-gender variance, the males exhibited less severe CNV and had less variance in size measurements, i.e. RPE Female \(659\pm 179\)\(\upmu\)m vs. Male \(397\pm 66\)\(\upmu\)m but no significant change. While the discrepancy in size increased variance of the measurement of a discrete time point, the longitudinal analysis was proportional and did not reveal any significant changes. The CV analysis results in comparable variance \(0.28\approx 0.24\); therefore, when analyzed as percent change, the trends were consistent in all lesions with no significant difference, despite variance in size (Table 1). The acute injury showed no sex discrepancy in lesion dynamics and Cv was low in all measurements. Because the lesion growth across gender is proportional to initial lesion size, the longitudinal analysis of individual lesions as percent change negates the concern of gender-induced variance in lesion size.