Certain reconstructive procedures, like auricular reconstructions, require thin and well-vascularized skin. The aims of this study were to analyze if the increased survival of expanded skin flaps was due to morphologic changes of the dermis, if thinning of short-time expanded skin was possible without harm to the microcirculation and if tissue selective cutting methods could be used to resect subcutaneous fat without damaging its vessels. Eighty-two 200-ml expanders were implanted into the trunk regions of 26 beagles and filled immediately with sterile saline. In the first series of experiments, the expansion was terminated after intervals of 0.5-5 weeks and dermal vessels were analyzed morphometrically. In the second series the expanded flaps were raised after 2 weeks and thinned solely surgically or with the additional use of an ultrasonic knife or with cutting by water jet. In contrast to sham flaps, the expanded skin showed only very few areas of necrosis and these were located superficially in most cases. The relative volume of the dermal vessels and their quantity showed a significant increase after the expansion. Additionally, the subcutaneous tissue could be thinned down to 0.4 mm with the water-jet-cutter. Findings demonstrated that the method used could create a well-vascularized skin flap of minimal thickness that could be very helpful for special reconstructive procedures.

This study shows the equivalency of diced cartilage in fascia grafts and isolated fascial grafts using allogenic fascia lata compared to autologous fascia. The type of cartilage used accounts for different long-term characteristics of diced cartilage in fascia grafts.

Objective The objective of the present study was to investigate the application of the water‐jet dissection method in parotid surgery by way of animal experiments, paying particular attention to the clinical and histological reactions of the facial nerve. Study Design An animal experimental study. Methods Total bilateral parotidectomies with retention of the facial nerve were performed on 19 beagle dogs by means of the Hydro‐Jet device (Andreas Pein Medizintechnik Company, Schwerin, Germany) using different jet diameters and operating pressures. All operations were performed with continuous intraoperative facial monitoring (Neurosign 100, Inomed Company, Teningen, Germany). The dogs were monitored postoperatively over an average period of 20.3 days (range, 14–35 d). Local findings and facial nerve status were documented daily. In a second phase, the dissected nerves were resected and the animals were killed. Samples of water‐jet–dissected parotid tissue, as well as all dissected nerve branches, underwent histological examination and were compared with clinical and electrophysiological findings. Results It was possible to perform operations easily on all parotid glands by means of the Hydro‐Jet using the small, 120‐μm jet at operating pressures of 40 to 60 bar and to dissect the facial nerve quickly and safely with retention of its functional capability (n = 34). The dissection of nerves using larger‐diameter jets (150 and 200 μm [n = 64]) resulted in a total of two reversible and seven irreversible partial pareses. Conclusions The study has shown that it is possible to perform tissue‐selective operations on the parotid gland by means of the Hydro‐Jet using the 120‐μm jet at operating pressures of 40 to 60 bar, ensuring safe, atraumatic dissection of the facial nerve with retention of its functional capability. The advantages of the new Hydro‐Jet method offer a valuable alternative compared with the normal dissection methods adopted in parotid surgery. Thus the results of the present investigation currently are being checked within the framework of a clinical study at our clinic.