Real-World Validation of the VIVEX Formula for Vitreous Volume Estimation in Vitreoretinal Surgery: A First Clinical...

Area of Science:

• Ophthalmology
• Medical Imaging
• Surgical Planning

Background:

• Accurate patient-specific vitreous cavity volume estimation is crucial for vitreoretinal surgery and tamponade procedures.
• The Vitreous Volume Exact (VIVEX) formula predicts vitreous volume using axial length (AL).

Purpose of the Study:

• To evaluate the clinical performance and accuracy of the VIVEX formula in a series of patients undergoing vitreoretinal procedures.
• To compare VIVEX-predicted volumes with intraoperative measurements.

Main Methods:

• Retrospective observational case series of 27 eyes undergoing vitreoretinal procedures.
• Comparison of VIVEX-predicted volumes (based on AL) with intraoperative measurements (aspirated fluid, injected/removed silicone oil).
• Accuracy assessed using mean absolute error (MAE), mean absolute percentage error (MAPE), Pearson correlation, regression analysis, and Bland-Altman analysis.

Main Results:

• VIVEX predictions showed strong correlation with intraoperative measurements (r=0.961, p<0.0001).
• Overall MAE was 0.48 mL and MAPE was 7.43%.
• Subgroup analysis indicated higher error (MAE 1.07 mL, MAPE 12.51%) during silicone oil removal.

Conclusions:

• The VIVEX formula demonstrates clinically useful accuracy for vitreous volume estimation in various surgical contexts.
• Caution is recommended during silicone oil removal due to potential measurement discrepancies.
• VIVEX can aid preoperative planning and volume targeting, but further multicenter studies are needed.