Axonal elongation into peripheral nerve grafts between thalamus and somatosensory cortex of the rat. An experimental model.

After destruction of the thalamocortical projections of one side in 12 adult rats, the ipsilateral thalamic ventrobasal nucleus was connected with the contralateral somatosensory cortex through an autologous peripheral nerve graft. Three months after the implanting procedure, horseradish peroxidase was applied to the transected nerve. Retrograde labeling of cells occurred in all examined animals. Evidence of newly formed thalamocortical connections provides the experimental basis to a model suitable for functional evaluations.

[Echinococcosis of the spine]. / Uber die Echinokokkose der Wirbelsäule.

21 patients with hydatid disease of the spine were operated on upon a 30-year period. The follow-up ranged up to 24 years. 12 cases underwent one or more reoperations, due to recurrences. 8 patients died between 1 and 21 years after the first operation. The surgical treatment usually allows only a transient remission and does not avoid recurrence or progression of the illness. Although the parasite cannot be wholly eradicated surgically, a prolonged and acceptable life with the disease can result from repeat surgical interference.

Long-term results of surgical treatment for redundant roots of the cauda equina.

Seven patients with redundant roots of the cauda equina were followed 2 1/2-10 years after surgical decompression. Improvement of signs and symptoms occurred in all patients. However, none of them was neurologically intact at the time of the last physical examination, although persistence of minimal neurological signs and/or occasional pain did not prevent a useful occupational activity.

Redundant nerve roots of the cauda equina.

Four cases of redundant nerve roots of the cauda equina are reported, and the pertinent literature is reviewed. This disorder mainly affects males. The clinical history ranges from months to decades. The illness often starts with low back pain or sciatica, or both. Motor and sensory impairment of the legs dominate the further course of the disease. Serpentine filling defects in the column of contrast are a characteristic (but inconstant) feature on myelograms. Abatement of signs and symptoms occurs following adequate decompression of the redundant roots.

Angiomas of the cerebellopontine angle.

Angiomas situated within the pontocerebellar cistern lie superficially on the ventrolateral aspect of the brain stem. Occasionally, minor extensions penetrate into the adjacent nervous structures. Five patients bearing such lesions were operated upon, using a microsurgical technique. Radical excision was performed in all cases. Within 2 to 12 months the patients had returned to their previous occupations, being fully able to work or attend school. There is increasing evidence for the effectiveness of surgical treatment of angiomas of the ventrolateral aspect of the brain stem and the cerebellopontine angle. The illness usually presents with hemorrhages of varying severity, ranging from mild to devastating. Impairment of consciousness, contralateral hemiparesis and ipsilateral cranial nerve palsies are the most frequent neurological signs after bleeding. The outcome following excision is primarily related to the preoperative condition. No additional deficits or only minor further impairment can be expected from surgical interference. Exploration is advisable whenever the malformation appears to lie on the surface rather than within the brain stem.

Long-term results of surgery for hydatid disease of the spine.

Long-term results of the surgical treatment of 18 patients with hydatid disease of the spine are reported. Recurrent signs of cord compression, requiring reoperation, occurred in half of the cases. The infestation can be controlled occasionally for over decades after the first operation, allowing the patients to have an acceptable life with their disease.

Cerebral water and electrolytes in experimental ischaemia following omental transposition to the brain.

Occlusion of the middle cerebral artery induces a local decrease in percentage of tissue dry weight in rabbit brain, associated with flux of sodium and potassium in reciprocal directions. Cortical swelling occurs also in remote non-ischaemic areas. Previous transposition of the omentum majus to the brain minimizes the onset of oedema consequent on occlusion of a major cerebral artery. Increasing experimental evidence points to the role of omental transposition in providing an effective source of collateral circulation, thus strongly affecting the threshold for infarction.

Surgical treatment of arteriovenous malformations of the posterior fossa.

Nine cases of arteriovenous malformations of the posterior fossa were operated upon, using microsurgical techniques. The excision was radical in eight patients. Seven of them, as well as the sole patient who had a partial removal of the malformation, returned to their previous occupations without neurological signs. In one case the preoperative deficit was unchanged. Some lesions that appear to penetrate the brain stem actually lie on its surface and can be dissected through an extrapial plane of cleavage. Extension of the malformation into the cerebellar peduncles requires dissection of the tangle and opening of the IVth ventricle.

[Microsurgical extirpation of extra-pial angiomas of the pons]. / Mikdrochirurgische Exstirpation extrapial gelegener Angiome des Pons.

Some arteriovenous malformations that are apparently located in the pons are in reality located on its surface. Thus, their extrapial dissection is possible. This is carried out under the surgical microscope and by means of the microtechnique. To nine available descriptions, the results obtained in four of our own patients are added: Three angiomas were in an extrapial antero-lateral position, one angioma reaching into the cerebellar hemisphere and causing a cerebellar haematoma. The fourth angioma was in the Brachium pontis and reached to the Flocculus and Loculus quadrangularis inferior. The patients (2 females, 2 males) were subjected to a subtemporal-transtentorial operation, the brachium-pontis angioma was operated on occipitally. Complete restoration was reached after the operation and the former activites were taken up again. The diagnosis was based on series angiography and computer tomography. The afferent vessels stemmed from one or several cerebellar vessels. The removal of the angioma requires the most subtile preparation.

Effect of reperfusion on the uptake of [3H] uridine in the gerbil brain after prolonged ischaemia.

The uptake of labelled uridine is reduced in the whole ischaemic hemispheres of gerbils subjected to unilateral carotid artery occlusion. Following circulatory restoration, brain structures that had an ischaemic insult of moderate intensity exhibit a progressively increased uptake. However, during reperfusion there is a tendency towards a clear cut definition of dead zones. This progression of the lesions seems to be related to a maturation phenomenon occurring in areas with an irreversible damage at the end of the ischaemic period.

Intramedullary epidermoid tumours. Remarks on the radical removal.

Three cases of intramedullary epidermoid tumours are reported. Microsurgical technique allowed a radical removal of the growths. The value of extirpation versus the evacuation of the cyst content is stressed.