Effect of cerebrospinal fluid leakage on wound healing in flap surgery: histological evaluation.

The aim of this study was to find out the effect of CSF leakage on wound healing after flap surgery. Sixteen male Wistar rats were used. The superiorly based rectangular dorsal skin flap 3 x 3 cm was elevated at the interscapular region. Through this opening, paraspinal muscle dissection and three-level bilateral laminectomy were done. Finally, a dura defect with a diameter of 3-4 mm was created. In the control group, laminectomy was performed as in the study group but the dura was left intact. Persistent CSF leakage was confirmed using isotope cisternography. At the end of 2-week study period, there was no necrosis, infection, or dehiscence of the flap in either group. On necroscopy, cyst formation over the dura defect was detected in 4 animals of the study group. Another gross finding in this group was intensive vascularization of the undersurface of the flap and wound bed. With HE staining, the tissue sections from the study group revealed new vessel formation with small diameter, increase in the reactional mesenchymal tissue, granulation tissue, degeneration of the striated muscle fibers, dystrophic calcifications, fat necrosis, and coagulation necrosis (ischemic necrosis). In the control group, there was only minimal lymphocytic invasion of the subdermal plane. In this study, we have shown that CSF leakage itself has effects on wound healing in the absence of known causative factors.