A. Pau

Mobile neurinoma of the cauda equina. Case report.

SummaryA mobile neurinoma arising from a redundant nerve root of the cauda equina is reported. The abnormal length of the nerve root allowed the neoplasm to move in the cranio-caudal direction along two segments of the spine.

Effect of omental transposition to the brain on protein synthesis in experimental cerebral ischaemia.

SummaryOcclusion of the middle cerebral artery severely affects the uptake of labelled leucine into various subcellular fractions from rabbit brain. Previous transposition of pedicled omentum to the cerebral surface maintains to a large extent the protein synthetic activity of the brain following arterial occlusion. The role of the transposed omentum in providing an effective collateral circulation and minimizing the occurrence of irreversible ischaemic lesions is stressed.

Vascular Malformations of the Brain in Achondroplasia Case Report

SummaryA further case of intracranial haemorrhage in achondroplasia is reported. At necropsy, an intracerebral haematoma communicating with the left temporal horn was found. Histological examinations revealed the presence of a cavernous angioma. The literature is reviewed.

Cerebral Water and Electrolytes in Experimental Ischaemia Following Omental Transposition to the Brain

SummaryOcclusion 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.

Omental transposition or transplantation to the brain and superficial temporal artery-middle cerebral artery anastomosis in preventing experimental cerebral ischaemia

SummaryTransposition of lengthened omentum to the brain surface, transplantation of an omental graft, or superficial temporal artery-middle cerebral artery anastomosis were performed in dogs prior to transcranial occlusion of the ipsilateral middle cerebral artery at its origin, including the bifurcation of the internal carotid artery. Both omentum and by-pass were able to reduce the changes in cerebral blood flow, somatosensory evoked responses, cerebral water and electrolyte content, consequent to the ischaemic insult. In the experimental conditions adopted in this study, the effect of omental transposition in maintaining high levels of flow throughout the entire occluded hemisphere was more marked compared to that resulting from the other methods, while the onset of ischaemic cerebral oedema was affected approximately at the same degree by all procedures. The results point to the role of the transposed omentum in providing an effective collateral circulation to the ischaemic brain.

Cerebral blood flow in minor cerebral contusion

Seventeen patients with minor cerebral contusion were selected from a series of patients with head injuries of various severity, who had undergone repeat evaluations of the regional cerebral blood flow. The mean global flow (expressed as mean global initial slope index) on early examination was found to be significantly lower, compared with that recorded in healthy volunteers. A tendency towards the recovery of higher flow values was apparent in repeat evaluations that were performed several weeks after the injury. Interhemispheric asymmetries of flow were a common occurrence, with lower perfusion and reduced attenuation values on computed tomography scans being, however, in good agreement only in approximately half of the cases.

Effect of Omental Transposition on to the Brain on the Cortical Content of Norepinephrine, Dopamine, 5-Hydroxytryptamine and 5-Hydroxyindoleacetic Acid in Experimental Cerebral Ischaemia

SummaryLocal cerebral ischaemia causes a significant decrease in norepinephrine, dopamine, 5-hydroxytryptamine in the cortical brain tissue of rabbits, associated with an increase in 5-hydroxyindoleacetic acid. Previous transposition of the omentum on to the brain surface maintains, to a large extent, physiological levels of these metabolites. This study stresses the role of the transposed omentum in reducing the effects of experimental occlusion of a major cerebral artery.

Surgical removal of a pontine haematoma associated with a cryptic angioma. Case report.

SummaryA further case of successful removal of an intrapontine haematoma related to a cryptic angioma is described. With a CT scan, the most accurate anatomical localization of the lesion may be obtained.

Unusual appearance of an acoustic neurinoma in CT scans

SummaryA large cystic neurinoma of the cerebellopontine angle is reported. This case is unusual in that the clinical history, CT patterns and plain radiological findings were rather misleading for the differential preoperative diagnosis.

Angiomas of the cerebellopontine angle.

SummaryAngiomas 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.ZusammenfassungDie in der ponto-zerebellären Zysterne gelegenen Angiome befinden sich oberflächlich auf der ventrolateralen Seite des Hirnstammes. Gelegentlich dringen sie in geringer Ausdehnung in die benachbarten Nervenstrukturen ein. Fünf Patienten mit solchen Mißbildungen wurden mit mikrochirurgischer Technik operiert. In allen Fällen wurde eine radikale Exstirpation ausgeführt. Alle Patienten nahmen ihre frühere Tätigkeit innerhalb von 2–12 Monaten nach der Operation wieder voll auf. Es gibt zunehmende Beweise für die Wirksamkeit der chirurgischen Behandlung der Angiome der ventrolateralen Seite des Hirnstammes und des Kleinhirnbrückenwinkels. In der Regel tritt die Krankheit mit Blutungen verschiedenen Ausmaßes auf. Bewußtseinsveränderungen, gegenseitige Hemiparese, gleichseitige Hirnnervenlähmungen sind die häufigsten neurologischen Zeichen nach einer Blutung. Das Ergebnis nach Radikalexstirpation hängt in erster Linie von dem präoperativen Zustand der Patienten ab. Der chirurgische Eingriff verursacht keine oder nur geringfügige neue Ausfälle. Eine chirurgische Exploration ist immer dann ratsam, wenn die Mißbildung auf der Oberfläche zu liegen scheint, anstatt im Hirnstamm selber.