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Background: Initial results on the application of the water-jet in a parotidectomy setting in an animal study demonstrate that there are morphologic changes which do, and some which do not, affect the clinial function of the facial nerve due to the different jet sizes and operating pressures used. In a further study the histomorphometric data of the facial nerve dissected by the water-jet should be evaluated and correlated to the different sizes of jet and operating pressures., Material and Methods: In total, 102 nerves (in 14 beagles) which had been dissected by water-jets of different sizes and operating pressures were evaluated. After an observation period of 21 days, including documentation of the clinical function of the facial nerve, the nerves were dissected. The number of nerve fibers and the diameter of the different nerve fibers were then evaluated., Results: All nerve fibers dissected with jet sizes of 120 and 150 μm showed an identical cumulative frequency of fiber diameters. All nerve fibers dissected with a water-jet of 200 μm showed morphologic and clinical abnormalities and--in terms of nerve fiber diameters--clear differences to the nerve fibers dissected with 120- or 150-μm jets. Altogether, there is a decrease in fiber diameter along the nerve course., Conclusion: Our data show a shift of larger diameters of the nerve trunk to smaller diameters in the terminal nerve fibers. This phenomenon has not been described in the literature to date and is probably not due to the water-jet. Additionally, our data show that 22% of the original nerve fiber damaged by the water-jet is sufficient to preserve the nerve's clinical function.

Background: The postoperative facial nerve palsy is a complication after parotidectomy which one is afraid of. The waterjet seems to be a surgical technic which allows separating different tissues without destroying important structures like vessels and nerves., Material and Methods: Totally, 106 nerve preparations, done by the waterjet of 14 beagles, were evaluated. According to a defined procedure during parotidectomy by waterjet different cones and pressure were used. After a period time of 21 days the trunk, the frontal branch and both oral branches of the facial nerve of both sides were dissected. The tissue preparation was done using the standard technic for EM-sections., Results: There are mainly changes due to the preparation like the reduction of nerve fibers and fibrosis depending which cones and pressure has been used., Conclusion: Therefore neither the size of the jet (120 or 150 μm) nor the operating pressure of 40 to 60 or 80 bar plays an important role for the function of the facial nerve. Damage to the nerve is mainly due to the preparation technic and the application time. Using the 200 μm jet there is regularly facial nerve damage.

In this study we expanded ileal segments of 8 pigs with an intraluminal expander over a period of 6 to 8 weeks till the volume had reached approximately sixfold of the starting volume. The morphological and morphometrical examinations showed flattened villi with elongated crypts and especially an increase in the thickness of the muscularis. The villi appeared flattened through scanning microscopy as well, but the structure of the microvilli was nearly normal. The proliferative activity in the muscularis, estimated immunohistochemically by a monoclonal antibody against PCNA, showed a threefold increase. So it can be assumed, that the increased thickness of the muscle layer was caused not only by muscle cell hypertrophy but also by hyperplasia. The activity of the alpha-glucosidase, a brush border enzyme, was clearly reduced. The minor cause of this effect was the direct damage of the microvilli from the expander, but the major cause was the exclusion of the ileal segment from the small bowel passage and the resulting lack of nutrients. With our technique it seems possible to create an ileum pouch, a stomach substitute or a urinary bladder substitute.

A retrospective study of 200 missed abortions was performed to determine whether morphological criteria alone are sufficient to ascertain a chromosomal aetiology. Placental changes were classified into five morphological and four morphometric groups, according to the severity of alterations, and were then correlated with the cytogenetic data. The rate of chromosome anomalies was approximately 50% and was thus not significantly different within the groups II-V, but it was 80% in group I, which covered the most severe placental alterations, namely the partial hydatidiform moles. There was a high incidence of triploidies in group I, trisomies with obligatory early lethality in groups II and III, and X-monosomies in group III. Our findings do not support previous evidence regarding the specificity of certain villous alterations in association with chromosome aberrations. Indeed, they indicate that the placental villi may react similarly to chromosomal and non-chromosomal disturbances and that placental morphology depends on the severity and the temporal onset of the underlying disorder rather than on its type. With respect to chorionic villus samplings (CVS), this would mean that an abnormal villous structure may be suggestive for a chromosome anomaly but does not exclude a normal karyotype.

Thiamine is important for oxidative metabolism, and B1 deficiency is thought to give rise to polyneuropathies. A group of male Wistar rats (n = 15) received a vitamin B1 deficient diet (group-a), and the pair fed control group (n = 20, group-b) received a normal diet with no vitamin deficiency. A second control group (group-c) was fed unrestrictedly with a standard diet (n = 19). All animals were examined for 25 weeks. The sensory nerve conduction velocity, the compound radicular, spinal and brain stem responses and the SEP were derived for tail and hind paw stimulation. The examination was repeated at 6-week intervals. There was no difference in nerve conduction between group-a and -b, but for both groups the conduction velocity was significantly slower than in group-c. The SEP latencies were significantly increased in group-a compared with group-b and also with group-c. The spinal and cerebral latencies were delayed in group-a. The diameters of myelinated nerve fibres were decreased in group-a compared with group-b, and in group-b compared with group-c. The results indicate that a specific polyneuropathy exists as a result of B1 deficiency, and that the sequelae of the lack of thiamine are pronounced in the CNS.