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H Aebersold

Publications and source records attributed to H Aebersold.

5 recordsLinked to original sources
PubMed1983

A modified Bodian stain for routine quantitative assessment of axonal degeneration in teased nerve fibers.

We present a modified Bodian method for staining axons in teased peripheral nerves. For test materials, guinea pig sciatic nerves, intact and cut in situ, were removed 3, 4 and 5 days after surgery. Notable characteristics of the stain are a strong contrast between the axon and surrounding myelin and easy detection of nodes of Ranvier. The method is suitable for the quantitative assessment of axonal degeneration.

Animals↗
PubMed1983

[Prognosis of severe craniocerebral trauma using neurophysiologic parameters].

40 patients in acute posttraumatic coma were assessed with help of 3 electrophysiological methods: short latency somatosensory evoked potentials (SEPs), brainstem auditory evoked potentials (BAEPs) and EEG, the results of which were compared with clinical outcome 3 months after the head injury (Fisher's exact probability test). SEPs proved to be the most reliable method for prognostic evaluation of these patients (p less than 0.001), followed by the EEG (p less than 0.002), the prognostic relevance of which, however, is limited by the use of narcotic drugs (barbiturates). BAEPs are less useful for the evaluation of these patients (p less than 0.01), which may be due to traumatic lesions of the cochlea, or even more often, to blood clots in the external ear canal, leading to conducting hearing loss. Conversely, the short axons of the auditory structures of the brainstem appear to be less susceptible to shearing forces of the primary mechanical impact, than the comparatively widely extended thalamocortical connections of the afferent somatosensory system.

Adolescent↗
PubMed1981

Representation of the visual field in the optic tract and optic chiasma of the cat.

The fibre arrangement in the optic chiasma (OC) and tract (OT) was investigated with anatomical and physiological methods. In silver impregnated material, principal fibre streams can be demonstrated. In the OC, fibre bundles from each eye cross in a regular basket weave pattern, but deviations of single fibres from the predominant stream are often seen. In the OT, fibres run essentially parallel, and crossings of individual fibres are mainly restricted to the periphery of the tract, or around capillaries. Fibres in the upper segment of the OT are of thin, in the lower segments of thick diameter. Individual fibres labelled by HRP injected in the lateral geniculate body (LGB) run essentially parallel over long distances. Ventromedially to the LGB, bifurcations are found with one branch entering the LGB, the other continuing. 57% of OT-fibres had a receptive field (RF) in the contralateral, 43% in the homolateral eye; 60% in the lower, 40% in the upper visual field; and 6% had a RF in the homolateral visual field, mostly near the vertical meridian. Fibres from the central area were underrepresented in our sample. Fibres from the two eyes were mixed. The RFs of consecutively recorded fibres showed a systematic progression only exceptionally. After plotting RFs of a single penetration on a transformed isodensity ganglion cell map of the visual field, the RF's were distributed along elongated paths on this map. In the OT, such paths ran parallel or slightly inclined relative to the horizontal meridian. They were restricted to either the upper or the lower quadrant or to a path along the horizontal meridian. In the OC, the RF-paths mostly crossed the horizontal meridian at an obtuse angle (average 70 degrees). Thus, the visual field representation rotates by nearly 90 degrees from the OC to the OT. In the OC, the central area is located anteriorly, in the OT dorsally, with the upper visual quadrant laterally and the lower medially. Fibres from the two eyes were mixed and, within the range of the scatter, RFs from the homo- and contralateral eye were in register. It is concluded, that the distribution of fibres in the OC and the OT show a basic retinotopic organization superimposed by scatter.

Animals↗