Haemodynamics Imaging of Swine Segmental Kidney Artery Using Duplex Doppler Technique.

INTRODUCTION: The aim of the study was to assess the usefulness of duplex Doppler to objectify swine renal arterial flow in physiological conditions. The pig kidney was selected for its morphological similarities to the human and for the results therefore offering data to wider research. MATERIAL AND METHODS: Six White Large x Landrace sows, of 48.5-53 kg b.w. were used. Vascular flow parameters were acquired with a convex probe USG device with a duplex Doppler function using pulsed waves (frequency range of 5-7.5 MHz). Segmental kidney arterial flow was measured. RESULTS: The RI values were within the 0.57 (min) to 0.6 (max) range, x RI was 0.58 (±0.014), and the SD2value was 0.0002. The PI index values ranged from 1.21 (min) to 1.3 (max), and x PI was 1.24 (±0.035). The value of SD2was 0.00123. In the S/D index, the results fell between 2.2 (min) and 2.49 (max), with x S/D of 2.29 (±0.117). The value of variance SD2was 0.0139. A double analysis of correlation between indices showed this to be almost certain and highly positive as confirmed by high correlation coefficients: r RI & PI 0.857, rho RI & PI 0.739, r RI & S/D 0.930, rho RI & S/D 0.941, r PI & S/D 0.913, and rho PI & S/D 0.754. The segmental kidney arterial flow spectrum evinced falls in PSV and PSV/LDV ratio, also noticed in the filling of the spectral window, comparing the renal to an interlobar artery. CONCLUSION: Swine were selected because of renal anatomical and haemodynamic similarity to humans. The most relevant values and indices approximated those in humans. The study anaesthetic protocol had a minor influence on the average RI, PI, and S/D indices.

Effect of Collateral Sprouting on Donor Nerve Function After Nerve Coaptation: A Study of the Brachial Plexus.

BACKGROUND The aim of the present study was to evaluate the donor nerve from the C7 spinal nerve of the rabbit brachial plexus after a coaptation procedure. Assessment was performed of avulsion of the C5 and C6 spinal nerves treated by coaptation of these nerves to the C7 spinal nerve. MATERIAL AND METHODS After nerve injury, fourteen rabbits were treated by end-to-side coaptation (ETS), and fourteen animals were treated by side-to-side coaptation (STS) on the right brachial plexus. Electrophysiological and histomorphometric analyses and the skin pinch test were used to evaluate the outcomes. RESULTS There was no statistically significant difference in the G-ratio proximal and distal to the coaptation in the ETS group, but the differences in the axon, myelin sheath and fiber diameters were statistically significant. The comparison of the ETS and STS groups distal to the coaptation with the controls demonstrated statistically significant differences in the fiber, axon, and myelin sheath diameters. With respect to the G-ratio, the ETS group exhibited no significant differences relative to the control, whereas the G-ratio in the STS group and the controls differed significantly. In the electrophysiological study, the ETS and STS groups exhibited major changes in the biceps and subscapularis muscles. CONCLUSIONS The coaptation procedure affects the histological structure of the nerve donor, but it does not translate into changes in nerve conduction or the sensory function of the limb. The donor nerve lesion in the ETS group is transient and has minimal clinical relevance.

Causes of Secondary Radial Nerve Palsy and Results of Treatment.

BACKGROUND The aim of this study was to analyze the causes that lead to secondary damage of the radial nerve and to discuss the results of reconstructive treatment. MATERIAL AND METHODS The study group consisted of 33 patients treated for radial nerve palsy after humeral fractures. Patients were diagnosed based on clinical examinations, ultrasonography, electromyography, or nerve conduction velocity. During each operation, the location and type of nerve damage were analyzed. During the reconstructive treatment, neurolysis, direct neurorrhaphy, or reconstruction with a sural nerve graft was used. The outcomes were evaluated using the Medical Research Council (MRC) scales and the quick DASH score. RESULTS Secondary radial nerve palsy occurs after open reduction and internal fixation (ORIF) by plate, as well as by closed reduction and internal fixation (CRIF) by nail. In the case of ORIF, it most often occurs when the lateral approach is used, as in the case of CRIF with an insertion interlocking screws. The results of the surgical treatment were statistically significant and depended on the time between nerve injury and revision (reconstruction) surgery, type of damage to the radial nerve, surgery treatment, and type of fixation. Treatment results were not statistically significant, depending on the type of fracture or location of the nerve injury. CONCLUSIONS The potential risk of radial nerve neurotmesis justifies an operative intervention to treat neurological complications after a humeral fracture. Adequate surgical treatment in many of these cases allows for functional recovery of the radial nerve.

The rabbit brachial plexus as a model for nerve repair surgery--histomorphometric analysis.

One of the most devastating injuries to the upper limb is trauma caused by the avulsion. The anatomical structure of the rabbit's brachial plexus is similar to the human brachial plexus. The aim of our study was to analyze the microanatomy and provide a detailed investigation of the rabbit's brachial plexus. The purpose of our research project was to evaluate the possibility of utilizing rabbit's plexus as a research model in studying brachial plexus injury. Studies included histomorphometric analysis of sampled ventral branches of spinal nerves C5, C6, C7, C8, and Th1, the cranial trunk, the medial part of the caudal trunk, the lateral part of the caudal trunk and peripheral nerve. Horizontal and vertical analysis was done considering following features: the axon diameter, fiber diameter and myelin sheath. The number of axons, nerve area, myelin fiber density and minimal diameter of myelin fiber, minimal axon diameter and myelin area was marked for each element. The changes between ventral branches of spinal nerves C5-Th1, trunks and peripheral nerve in which the myelin sheath, axon diameter and fiber diameter was assessed were statistically significant. It was found that the g-ratio has close value in the brachial plexus as in the peripheral nerve. The peak of these parameters was found in nerve trunks, and then decreased coherently with the nerves travelling peripherally.

Magnetic resonance imaging and brainstem auditory evoked responses in the diagnosis of cerebellar cortical degeneration in american staffordshire terriers.

The aim of the study was to determine the diagnostic usefulness of magnetic resonance imaging (MRI) and brainstem auditory evoked responses (BAER) in dogs suspected of having cerebellar cortical degeneration (CCD). In the years 2009-2011, six dogs with suspected CCD were examined. Both MRI and BAER examinations revealed abnormalities in all dogs (100%). By MRI, T2-weighted midsagittal images revealed an increased amount of cerebrospinal fluid (CSF) surrounding the cerebellum within the sulci of the folia in all dogs (100%). In 4 out of the 6 dogs (66.66%), cerebellar hypoplasia was more visible in the region of the dorsal cerebellar lobules. In 5 out of the 6 dogs (83.33%), the fourth ventricle was enlarged. In our studies, the brain to cerebellum ratio evaluated on the midsagittal image was 11.93%, in comparison to 14.9% in normal dogs. By BAER examination, the amplitude of the first and second waves was diminished and III-V interlatency was prolonged in 5 out of the 6 dogs (83.33%). In one out of the 6 dogs (16.67%), only the III-V interlatency was prolonged. In one dog (16.67%), somato-nervous deafness in the left ear was detected, whereas in the right ear the III-V interlatency was prolonged. MRI of the cerebellum is a reliable method for the antemortem diagnosis of CCD in American Staffordshire terriers, as is BAER examination. BAER is an objective diagnostic tool, which - along with other diagnostic modalities - can be helpful in the assessment, management and follow-up of dogs with cerebellar abiotrophy. It proved to be useful in determining the severity of neurological lesions in comparison to MRI findings, as well as in assessing the prognosis.