Hydro-jet cutting: a method for selective surgical dissection of nerve tissue. An experimental study on the sciatic nerve of rats

The aim of this study was to answer the question: is it possible to save mo tor nerves when dissecting tissue with the hydro-jet dissector? In order to study the influence of the hydro-jet on motor nerves the function of the s ciatic nerves of 10 Wister rats was evaluated. The sciatic nerves were diss ected bilaterally and only the left one was exposed to the hydro-jet. The w ater-jet emerged from a nozzle with a diameter of 0.1 mm and was applied to the nerve for 2, 5 or 10s and with jet pressures of 80, 85 and 90 bar, res pectively. After the operation the animals were observed for 5 months in or der to monitor the degree of limping using a scale with 10 clinical grades of function, The months postoperatively the animals were sacrificed and the sciatic nerves mere studied by light and electron microscopy. It was found that hydro-jet pressures of 80 bar and exposure times of 2s had already le ad to irreversible damage to the sciatic nerve, Therefore further studies w ith lower pressures or shorter exposure times are required before consideri ng hydro-jet cutting for parotid gland surgery, It must be confirmed as har mless to motor nerves before applying this method in humans. (C) 1999 Europ ean Association for Cranio-Maxillofacial Surgery.