# Real-time monitoring of spinal cord hemodynamics with laser speckle contrast imaging during pedicle subtraction osteotomy in rabbits

## TL;DR

This study shows that laser speckle contrast imaging can track blood flow changes in the spinal cord during surgery in rabbits, offering a potential tool for protecting the spinal cord during operations.

## Contribution

The study demonstrates the novel use of LSCI for real-time, non-invasive monitoring of spinal cord hemodynamics during osteotomy.

## Key findings

- LSCI captured significant decreases in spinal cord blood flow perfusion after osteotomy and dura removal.
- Posterior spinal artery diameter expanded after osteotomy but contracted during compression and dura removal.
- LSCI proved reliable for real-time monitoring of hemodynamic changes during spinal surgery.

## Abstract

This study aimed to evaluate the efficacy of Speckle Contrast Imaging (LSCI) in real-time monitoring of spinal cord hemodynamic changes during spinal osteotomy in rabbits and to assess its clinical relevance for intraoperative blood flow management.

Thirty-one healthy male New Zealand white rabbits (clean-grade) were subjected to Pedicle subtraction osteotomy (PSO) under general anesthesia. The spinal cord and posterior vasculature were surgically exposed, and LSCI was employed to quantify blood flow perfusion (Perfusion Units, PU) and posterior spinal artery diameter (μm) at four critical stages: (1) pre-osteotomy (baseline), (2) post-osteotomy, (3) post-osteotomy site compression, and (4) post-dura removal.

LSCI successfully captured dynamic hemodynamic changes: Blood flow perfusion decreased significantly from baseline (519.22 ± 137.87 PU) to post-osteotomy (315.00 ± 50.24 PU, P < 0.05), partially recovered after osteotomy site compression (409.16 ± 55.09 PU, P < 0.05), and further declined post-dura removal (237.73 ± 40.46 PU, P < 0.05). Arterial diameter expanded from 83.13 ± 14.35 μm (baseline) to 388.53 ± 64.62 μm post-osteotomy (P < 0.05), then contracted during compression (269.01 ± 50.48 μm) and dura removal (225.84 ± 50.53 μm, both P < 0.05).

LSCI provides reliable, non-invasive real-time monitoring of spinal cord hemodynamics during osteotomy, demonstrating significant perfusion and vascular diameter fluctuations. This technology offers a promising tool for intraoperative spinal cord protection and warrants further clinical translation.