## 3 Results
### Vitreoretial Surgery
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multicolumn{6}{c}{**SAN GOVANNI DI DIO (CAGLIARI)**} \\ \hline \hline \multicolumn{6}{c}{**PRE-COVID-19 YEAR**} & \multicolumn{6}{c}{**COVID-19 YEAR**} \\ \hline
**Period** & **N** & **Weekly Mean \(\pm\) SD** & **Period** & **N** & **Weekly Mean \(\pm\) SD** & \(\Delta\) & \(p\)**-Value** \\ \hline First quarter & 105 & 8.07 \(\pm\) 3.27 & Lockdown & 61 & 4.69 \(\pm\) 2.81 & \(-\)41.9\% & _0.009_ \\ \hline Second quarter & 63 & 4.84 \(\pm\) 3.95 & Unlock & 58 & 4.46 \(\pm\) 3.15 & \(-\)7.94\% & 0.78 \\ \hline Last six months & 164 & 6.30 \(\pm\) 2.82 & Second Wave & 170 & 6.53 \(\pm\) 3.38 & \(+\)3.66\% & 0.79 \\ \hline Total & 332 & \multicolumn{6}{c}{Total} & 289 & \(-\)27.26\% & 0.2 \\ \hline \multicolumn{6}{c}{**MATER DOMINI (CATANZARO)**} \\ \hline \multicolumn{6}{c}{**PRE-COVID-19 YEAR**} & \multicolumn{6}{c}{**COVID-19 YEAR**} \\ \hline
**Period** & **N** & **Weekly Mean \(\pm\) SD** & **Period** & **N** & **Weekly Mean \(\pm\) SD** & \(\Delta\) & \(p\)**-Value** \\ \hline First quarter & 62 & 4.77 \(\pm\) 2.65 & Lockdown & 51 & 3.92 \(\pm\) 2.84 & \(-\)17.74\% & 0.44 \\ \hline Second quarter & 90 & 6.92 \(\pm\) 4.05 & Unlock & 101 & 7.76 \(\pm\) 3.91 & \(+\)12.22\% & 0.59 \\ \hline Last six months & 123 & 4.65 \(\pm\) 3.00 & Second Wave & 207 & 7.96 \(\pm\) 5.28 & \(+\)71.07\% & _0.007_ \\ \hline Total & 273 & \multicolumn{6}{c}{Total} & 359 & \(+\)31.50\% & _0.04_ \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Number of vitreorentinal surgical procedures performed at San Giovanni di Dio (SGD), University of Cagliari, and Mater Domini, University Magna Gracia of Catanzaro (UMG), divided by periods of lockdown, unlock, and second wave, respectively. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multicolumn{6}{c}{**SAN GOVANNI DI DIO (CAGLIARI)**} & \multicolumn{6}{c}{**MATER DOMINI (CATANZARO)**} \\ \hline
**Diagnosis** & **PRE-COVID-19** & **COVID-19** & \(\Delta\) & **PRE-COVID-19** & **COVID-19** & \(\Delta\) \\ \hline REITNAL & 123 & 112 & \(-\)9\% & 91 & 148 & 63\% \\ DETACHMENT & 20 & 30 & 50\% & 36 & 49 & 36\% \\ \hline EPIREITNAL & 59 & 34 & \(-\)42\% & 40 & 45 & 13\% \\ \hline SILICONE OIL IN & 13 & 21 & 62\% & 33 & 39 & 18\% \\ VITREOUS CAVITY & 45 & 35 & \(-\)22\% & 20 & 26 & 30\% \\ \hline MACULAR HOLE & 44 & 24 & \(-\)45\% & 12 & 20 & 67\% \\ \hline LENS FRAGEMENTS IN VITREOUS CAVITY & 5 & 9 & 80\% & 18 & 13 & \(-\)28\% \\ \hline IOL DISCACTED IN VITREOUS CAVITY & 8 & 10 & 25\% & 18 & 12 & \(-\)33\% \\ \hline DIABETIC RETINOPATHY & 10 & 11 & 10\% & 3 & 5 & 67\% \\ \hline SYNCHYSIS & 0 & 1 & - & 0 & 1 & - \\ SCINTILLANS & & - & - & 1 & 1 & 0\% \\ \hline VITRTIIS & - & - & - & 3 & 0 & \(-\)100\% \\ \hline ENDOPHTHALMITS & 1 & 0 & - & - & - & - \\ \hline OCULAR TRAUMA & 4 & 112 & \(-\)50\% & - & - & - \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Comparison of different diagnoses of surgically treated posterior segment diseases at San Giovanni di Dio (SGD), University of Cagliari, and Mater Domini, University Magna Gracia of Catanzaro (UMG). The activity of the UMG vitreoretinal surgical unit significantly increased by 31% during the pandemic (_p_ < 0.05). In particular, 359 surgical interventions for posterior segment diseases were performed during the COVID-19 year, and they were distributed as follows: 51 during the lockdown phase (weekly mean 3.92 \(\pm\) 2.84), 101 during the unlock (weekly mean 7.76 \(\pm\) 3.91), and 207 during the second wave (weekly mean 7.96 \(\pm\) 5.28). Conversely, during the pre-COVID-19 year, a total of 273 surgeries were carried out: 62 procedures in the first quarter (weekly mean 4.77 \(\pm\) 2.65), 90 operations in the second quarter (weekly mean 6.92 \(\pm\) 4.05), and 123 during the second wave (weekly mean 4.65 \(\pm\) 3.00). The highest number of interventions were performed during the second wave, corresponding to 71% of the total (_p_ < 0.05).