Is There Postoperative Fluid Accumulation After the Unilateral Biportal Endoscopic Technique as Minimally Invasive Spine Surgery: In Vivo Study.

Aim: To establish the presence and amount of fluid accumulation in UBE procedure, and the relationship of fluid management with other variables.

Material and methods: All patients underwent UBE spinal surgery with one level between September 2019 and February 2022. The exclusion criteria were determined. All early MRI-STIR images from all patients up to the 12th-h postoperatively were collected. All MRI STIR images were evaluated by matrix laboratory (MATLAB) for fluid accumulation. Statistical analysis was done by SPSS 22.0 (IBM, Armonk, NY).

Results: The hospital archive records of 39 patients were assessed in this study. The mean matrix laboratory measurements (cm3) for women was 58.75 ± 18.870 and that for men was 49.86 ± 18.977. No significant difference was found in terms of gender in matrix laboratory value (p=0.161). Matrix laboratory value was negatively correlated with height but positively correlated with BMI and the subcutaneous adipose tissues. There was no significant difference between the genders in terms of age, BMI, and matrix laboratory.

Conclusion: Any complications of fluid accumulation in the UBE study group were not detected. The fluid accumulation in UBE was within physiological limits. Matrix laboratory is a good and applicable method for spine surgery.