PubMed HealthSearch

Biomedical subjects

H P Schmitt

Publications and source records attributed to H P Schmitt.

At least 19 recordsLinked to original sources

Quantitative analysis of the size distribution of target- and targetoid fibres employing the method of Daeves and Beckel for mixed distributions.

An analysis of frequency distribution is performed in 250 target and targetoid fibres each from the anterior tibial muscle of a case with rapidly proceeding denervation atrophy. Following plane measurements on cross sections the size data were analysed according to the method of Daeves and Beckel [1] for mixed distributions. Three homogeneous normally distributed populations could thus be extracted from the mixed distributed sample. The largest population represents target fibres with a normal size range, while the second one encloses hypertrophic fibres, and the third and smallest one consists of fibres ranging within atrophic size limits. These findings support the previous presumption that targets predominantly occur in fibres of normal size and can therefore be regarded as manifestations of an early stage of denervation atrophy. The targetoid fibres, on the contrary, are of an atrophic size by 84%, while only a small population of about 15% contains targetoid fibres of a normal size on cross section.

Aged

Skeletal muscular atrophy in malignant tumour diseases: neurogenic or unspecific?

Muscles from patients who had died from malignant tumours were examined with regard to changes in the intramuscular nerve twigs and the axon terminals or the motor end-plates, respectively. Three muscles from each of 120 cases were obtained at autopsy and stained with conventional methods. Nineteen cases with pronounced small-group and sometimes large-group atrophy were selected. Myelin and axon preparations displayed various changes of the small nerve branches and the axon terminals. Their significance for the atrophy frequently observed in the muscles of cancer patients is discussed.

Axons

The influence of chronic deep brain stimulation on excitability and morphology of the stimulated tissue.

Bipolar electrical stimulations of the rostal hippocampus and of the amygdala were performed at irregular intervals in wakeful unrestrained cats via chronically implanted glass-insulated stainless steel electrodes. The excitability of the stimulated tissue remained unchanged during the whole investigation period of six months up to one and a half years, as was revealed by regularly performed comparisons of shape, latency, and amplitude of evoked potentials elicited by electrical stimulation of the rostral hippocampus and recorded within the ipsilateral mammillary body. The histological examination of the stimulated tissue revealed a fibrillary gliosis due to the trauma caused by the insertion of the electrodes, but no signs of additional tissue damage due to electrical stimulation or chronic mechanical irritation. The results indicate that it is possible to perform therapeutic stimulations of deep brain structures for long periods without inducing relevant changes in morphology or electrical responsiveness of the stimulated tissue. No kindling phenomena are to be expected, if the stimulations are performed at irregular intervals.

Amygdala

Chronic electrical stimulation of the thalamic unspecific activating system in a patient with coma due to midbrain and upper brain stem infarction.

Chronic intermittent bipolar electrical stimulation of the left nucleus reticulatus polaris thalami was performed in a patient in a state of subcoma due to ischaemic infarction of wide medial parts of the midbrain, mainly the tegmentum, and the right-sided mediobasal parts of the forebrain. Stimulation immediately resulted in autonomic reactions and behavioural arousal reactions during the periods of stimulation. Longterm effect consisted of a rise in the level of clinical responsiveness for a period of seven weeks. A preexistent severe pneumonia disappeared completely after one week of stimulation and returned after seven weeks. The results are discussed on the basis of the pathoanatomical findings and of the physiological functions of the damaged as well as of the stimulated areas.

Aged

Peripheral intraaxonal storage in Tay-Sachs' disease (GM2-gangliosidosis type 1.

Considerable intraaxonal lipid storage was observed in intramuscular nerve fibres mainly of the extraocular muscles and less frequently in limb muscles of a 3-year-old child, which had suffered from Tay-Sachs' disease. Many axons of the small intramuscular nerve twigs and of the terminal and preterminal nerve endings showed spherical and cylindrical enlargements containing granular storage material of the same staining properties as the material in the central nervous system. The identify of the axonal and the neuronal storage material was further confirmed by electron-microscopical demonstration of typical multilamellated cytoplasmic bodies (MCBs) in both of them. In addition, silver impregnation and electron microscopy revealed dystrophic changes with an increase of argyrophilic filamentous material within some of the axonal distensions, indicating that the latter were probably due to both a lipid storage and an unspecific dystrophic process.

Atrophy

[Differential-diagnostic problems with the brain abscess in axial computerized tomography (author's transl)].

On the base of three autoptically controlled cases with ring-shaped findings in the CT the problem of the differential diagnosis of the brain abscess in axial computerized tomography is discussed. A brain abscess must especially be taken into account when the hyperdense anulus already occurs without enhancement by contrast media. The ring-shaped finding is then caused by the high amount of collagen fibres within the abscess membrane, which has no comparable correlate in other focal processes of the brain.

Autopsy

[Contribution to the knowledge of the "periostitis ossificans interna" of the cranial vault (author's transl)].

An unusual observation of hyperostosis of the frontal bone exhibiting five alternating layers of compact and cancellous bone on cross section is demonstrated. The peculiar, hitherto not described hyperostosis occurred in an 18 year old female suffering from recurrent chronical pachy- and lepto-meningitis since birth. A second similar observation was made in a 15 year old male, trepanated because of an epidural abscess. Similar accessory layers of cancellous bone on the internal surface of temporal bone suggested that also the first observation had to be interpreted as an unusually extensive form of periostitis ossificans, only involving the frontal bone, due to the recurring inflammation processes of the meninges.

Adolescent

Involvement of the larynx in a congenital "myopathy", unilateral aplasia of the arytenoid, micrognathia, and malformation of the brain--a new syndrome?

Neuromyopathic changes were found in various limb muscles and in intrinsic laryngeal muscles of a two month old girl. She had been noted to have micrognathia, arthrogryposis and congenital stridor and died as a result of respiratory insufficiency and aspiration. Autopsy revealed an absent left arytenoid cartilage and severe histogenic abnormalities of the brain. Although the muscles involved showed a mainly myopathic pattern, marked signs of peripheral neurogenic involvement were present. These differed from motor neuron disease or aplasia of anterior horn cells. These findings cast a new light on the discussion of unclassified congenital myopathy resembling the picture of congenital muscular "dystrophy". This is the first case of congenital neuromyopathy in which involvement of intrinsic laryngeal muscles has been demonstrated morphologically.

Arthrogryposis

Quantitative analysis of voluntary muscles from routine autopsy material with special reference to the problem of remote carcinomatous changes ("neuromyopathy").

Specimens from the deltoid muscle of 210 randomly selected autopsy cases without previous clinical evidence of primary neuromuscular impairment were examined with regard to the influence of extramuscular diseases on voluntary muscle. Differences between malignant tumours and other disorders were of special interest with respect to the question of the possible existence of a remote effect of cancer on skeletal muscle. The number of central nuclei within muscle fibre cross sections was considered as the most simple parameter for myopathic reaction. Atrophic fibre changes were examined quantitatively by measurement of the orthogonal fibre diameters and calculating the variation of fibre size. In addition, a semi-quantitative histological evaluation of the muscles was performed. While tumor cases did not show a significant difference from the remainder with respect to myopathic changes, they did display a significant difference with regard to scattered and small-group fibre atrophy. The reasons for the muscular changes are discussed. From the present investigation the changes seem to be due chiefly to metabolic impairment and wasting. No signs for a specific carcinotoxic effect on skeletal muscles could be demonstrated.

Atrophy

Syndrome of primary transtentorial cerebellar displacement--"inverse Chiari type II syndrome".

Transtentorial upward displacement of parts of the cerebellum and the brain stem into the supratentorial space, a condition which has occasionally been described in the literature since 1958 in children with hydrocephalus and spina bifida, is demonstrated in one case together with a discussion of its pathogenesis. A former hypothesis regarding the condition as a result of long standing shunt treatment of the hydrocephalus with supratentorial decompression is opposed. Different findings in the present and in two formerly recorded observations point out that the cerebellar upward displacement must be a prenatally originated malformation complex associated with hydrocephalus. The main criteria of the syndrome, which seems to be very much related to the Arnold-Chiari malformation, are summarized.

Abnormalities, Multiple

[Multiple fractures of the atlas with delayed fatal thrombosis of vertebral artery following "whiplash" injury of the neck (author's transl)].

Report of the case of a 62 year old male, who died in a car crash on his way home from duty, when he had a frontal collison with annother car at a speed of about 70 km per hour. After the collision, the car had completely turned over to its wheels. As the man had put on the seat belts, he had not been cast against the front window so that there were no head injuries. Following an unconsciousness of about ten minutes the patient recovered quickly and was already fully oriented when arrived at hospital. No neurological symptoms could be substantiated. He only suffered from pain of the neck and had a marked swelling of the left side of the neck. A burstin fracture of the atlas vertebra (Jefferson-fracture) was overlooked in routine X-rays of the craniovertebral region. Eight days after the accident, the hitherto "well improving" patient died suddenly and unexpectedly. The autopsy revealed an obstructing thrombosis of the left vertebral artery, less than 24 hours old. The wall of the artery showed numerous dissecting ruptures with intramural bleedings.

Accidents, Traffic

[Clinical findings and roentgenological diagnosis of the anomalies in the craniocervial region (author's transl)].

Osseous anomalies of the craniocervical junction may induce grave neurological disturbances and even lead to sudden death in exceptional cases. Therefore a correct diagnosis with painstaking demonstration of the extent of all anomalies must be established. This can be achieved exclusively by roentgenological studies. Clinical symptoms can only provide a lead to the underlying disease. In the present paper, the special problems of the radiology of craniocervical malformations are discussed and illustrated with own observations, which include specimen radiography.

Adult

Considerations on the morphogenesis of target and targetoid fibres based on morphometric investigations.

A man of 68, who died from a second heart stroke had neurogenic atrophy of the legs. The anterior tibial muscle showed abundant target and targetoid fibres. Half a year prior to death he had increasing weakness and wasting of the legs. The morphometric evaluation of the target and targetoid fibres showed a considerable independence of the plane size of the single zones from the total gauge of the fibres on cross section. Only a small part of the variation in size of zone 2 (4%) depended on the size of the target, indicating that zone 2 cannot just be a passive product of a shrinkage and disappearance of the target, but that there must be an active process, which leads to the change in zone 2. The regressive development of the centrally demarcated fibrillar bundle (target) is regarded as secondary degeneration following interruption of the nutritional supply.

Aged

Partial transtentorial displacement of the cerebellum and the brain stem in hydrocephalus-a primary condition or a result of treatment?

Two cases of upward displacement of parts of the brain stem and the cerebellum are discussed. In both cases shunts for a hydrocephalus had been operating for a long time (three and a half years in one and seven months in the other). One infant had a meningomyelocele but no complete Arnold-Chiari malformation. The cause of the hydrocephalus in the other case was doubtful, but was thought to be transtentorial displacement of the brain stem and the cerebellum causing traction on the pons and consequent meningeal fibrosis with obstruction of the cisterna pontis. In this case osseous hypoplasia of the posterior fossa was excluded by craniometry, so the upward displacement must have been due to hypoplasia of the tentorium cerebelli and its low attachment to the occiput, bringingg about a narrowing of the infratentorial space. The authors believe the condition to be a primary malformation, and reject the hypothesis of secondary herniation following long standing supratentorial decompression. The concept of a primary malformation is supported by previous descriptions of the condition in cases with spina bifida, Arnold-Chiari malformation, and hydrocephalus without shunting, as well as by other features in the cases which have been recorded.

Age Factors