Role of arachidonate metabolites in the genesis of cerebral vasospasm.
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6-Ketoprostaglandin F1 alpha↗
Biomedical subjects
V Silvani
Publications and source records attributed to V Silvani.
[Cerebral vasospasm. Clinical and experimental aspects].
A large number of experimental data suggest a possible biochemical hypothesis for the trigger stimulus of cerebral vasospasm after subarachnoid hemorrhage (SAH). Among several classes of possible spasmogens, arachidonic acid metabolites may play a primary role. Authors have measured with radioimmunoassay technique (R.I.A.) the levels of four arachidonate metabolites (PGD2, TxB2, 6-keto-PGF1 alpha and i-LTC4) in lumbar and cisternal cerebrospinal fluid (CSF) of patients admitted with diagnosis of aneurysmal SAH. In all cases a significant activation of arachidonate metabolism is found, if compared to control cases. Patients with demonstrated vasospasm have significantly higher CSF levels of PGD2 and i-LTC4. Cisternal CSF levels of four metabolites are significantly higher than lumbar CSF levels. This suggests the correlation between subarachnoidal clot extension and the risk for vasospasm. Authors also present an experimental animal model of SAH, which is reliable from a pathological standpoint. This model could be therefore used in the study of neurochemical and neuropharmacological aspects of SAH.
6-Ketoprostaglandin F1 alpha↗
[Giant and intracavernous aneurysms of the carotid arteries. Their treatment by extracranial-intracranial bypass and gradual occlusion of the carotid artery in the neck].
Intracavernous aneurysms are a clinical diagnostic and technical problem. The risk of a direct surgical clipping, whenever possible, is high. Carotid ligation remains the classical surgical treatment for inaccessible aneurysms. Internal carotid artery (ICA) ligation is more effective than common carotid artery (CCA) ligation but carries a higher risk of cerebral ischaemia. The performance of ipsilateral extra-intracranial by-pass (EIAB) helps to maintain blood flow in the cerebral hemisphere. It also decrease the collateral flow formation through the circle of Willis with turbulence in the aneurysmal sac, thus enhancing thrombosis. A series of five cases is reported. The results are satisfactory except in one patient who died in the immediate postoperative period for malignant hemispheric edema, in spite of the patent by-pass. The EIAB can reduce but not eliminate the risk of ischaemic complications related to ICA ligation.
Aged↗
Prostaglandin D2 monitoring in human CSF after subarachnoid hemorrhage: the possible role of prostaglandin D2 in the genesis of cerebral vasospasm.
Experimental and clinical studies indicate that cerebral vasospasm following subarachnoid hemorrhage (SAH) may be caused by changed biochemical properties of the endothelium and vascular smooth muscle cell exposed to vasoactive substances synthetized by cerebral arteries and released in clotted blood. Many compounds have been identified in CSF from SAH patients: Thromboxanes A2 and B2, Prostaglandins F2 alpha, E2 and D2 are the major prostanoids incriminated in the causation of cerebral arterial spasm. We have monitored the CSF PGD2 concentrations with serial lumbar punctures at different intervals from the hemorrhage in 16 patients admitted for SAH: PGD2 was measured with radioimmunoassay as its 9-methoxy derivative. The lumbar CSF PGD2 concentration ranges from 0.11 to 1.53 ng/ml. In 7 cases vasospasm was angiographically demonstrated. 9 patients presented no clinical or radiological evidence of vasospasm. In 5 cases cisternal CSF samples were available at the operation by cisternal punctures. There was no correlation between CSF PGD2 concentration and clinical course. In the 7 cases with evidence of vasospasm a significant increase of CSF PGD2 corresponded to neurological deterioration. In all 9 cases without evidence of vasospasm CSF PGD2 concentration trend was in a steady-state. The cisternal CSF PGD2 concentration was higher than lumbar CSF concentration in cases with arterial spasm. This suggests the importance of the clotting phenomenon in vasospasm onset after SAH. PGD2 is one of the most important spasmogens in clotted blood. Although its role in the genesis of vasospasm onset remains to be defined, its vasospastic action, in addition to that of other analogous compounds, seems to be relevant.
Humans↗
Venous saclike aneurysm of the central nervous system.
A case of cerebral venous saclike aneurysm of the parietal cerebral cortex is presented with surgical and histological confirmation. Computed tomographic findings are non-specific but very useful for detecting the lesion. Angiographic findings are not so obvious as with an arteriovenous malformation, but are necessary for the final diagnosis of a cerebral varix.
Female↗
Surgical treatment of multiple supratentorial aneurysms.
Multiple aneurysms are a common radiological finding in patients who have had a SAH. The doubtful question in the treatment of multiple aneurysms is whether to delay operation or treat the unruptured aneurysms conservatively. Patients with multiple intracranial aneurysms treated conservatively, have a late-rebleeding rate of 3% every year. We report our experience in seven cases treated surgically with complete exclusion of all the aneurysms. Surgical morbidity and mortality rates vary between 5 and 10%, although surgical procedures must be performed as soon as possible and should be preferred to delayed treatment.
Adult↗
Prostacyclin and vasospasm in subarachnoid hemorrhage from ruptured intracranial aneurysm. A preliminary clinical study.
Experimental and clinical observations suggest the importance of arachidonate metabolites in the genesis of symptomatic cerebral vasospasm after subarachnoid hemorrhage. Prostacyclin (PG12) has a well demonstrated vasodilator action. The authors monitored CSF prostacyclin concentration in 12 consecutive cases of subarachnoid hemorrhage with the purpose of correlating the prostacyclin concentration trend with the clinical course and the risk for vasospasm. In three cases patients presented with clinical and radiological signs of vasospasm. CSF prostacyclin concentration showed a typical decreasing trend, which amounted to a minor form of protection from vasospastic agents. The nine cases which did not develop vasospasm demonstrated no significant changes in the prostacyclin CSF concentration trend. The authors also presented four cases in which cisternal CSF samples were available. In one case of developing vasospasm, the cisternal prostacyclin concentration was seven times lower than the highest lumbar CSF concentration. In three cases without evidence of vasospasm cisternal CSF demonstrated a balanced biochemical situation and a minor risk of vasospasm.
6-Ketoprostaglandin F1 alpha↗
Proliferative characteristics and ploidy of human brain tumors by DNA flow cytometry.
We studied nuclear DNA distribution by flow cytometry in 59 human brain tumors. Samples were frozen at -20 degrees C immediately after surgery and unicellular suspensions were obtained with a mechanical dissociation technique. Nuclear DNA was stained with propidium iodide. Normal human brain tissue was used as a diploid reference standard. In 86.3% of benign tumors an unimodal DNA distribution with a DNA index usually within the diploid range was found. Among malignant tumors, 64% had un unimodal DNA distribution with diploid or near-diploid modal DNA content. The remaining 36% showed an additional cell peak with a DNA index ranging from 1.15 to 1.92. The percentage of S-phase cells was higher in malignant (median = 3.8) than in benign tumors (median = 1.9) (p less than .001), without correlation to histological tumor subtype.
Aneuploidy↗
Combined STA/MCA arterial bypass and gradual internal carotid artery occlusion for treatment of intracavernous and giant carotid artery aneurysms.
Intracavernous aneurysms are a clinical diagnostic and technical problem. The risk of a direct surgical clipping, whenever possible, is high. Carotid ligation remains the classical surgical treatment for inaccessible aneurysms. Internal carotid artery (ICA) ligation is more effective than common carotid artery (CCA) ligation but carries a higher risk of cerebral ischaemia. The performance of ipsilateral extra-intracranial arterial bypass (EIAB) helps to maintain blood flow in the cerebral hemisphere. It also may decrease the collateral flow formation through the circle of Willis with turbulence in the aneurysmal sac, thus enhancing thrombosis. A series of five cases is reported. The results are satisfactory except in one patient who died in the immediate postoperative period for malignant hemispheric edema, in spite of the patent bypass. The EIAB can reduce but not eliminate the risk of ischaemic complications related to ICA ligation.
Aged↗
[Chemotherapy and immunotherapy of intracranial malignant gliomas].
Although in recent years a great attempt has been made in brain tumor chemotherapy, this therapeutic approach appears to be conditioned by a large number of problems such as cell kinetics, tumor growth modalities, and drug delivery. Therefore only a small number of drugs (BCNU, CCNU, streptozotocin, and procarbazine) clearly demonstrate effectiveness against these tumors. Immunotherapy raises the same and other problems. In fact, if immune reaction is quite possible inside the brain, unfortunately current immunostimulant methods are unable to produce significant improvements.
BCG Vaccine↗
Idiopathic hydrocephalic dementia in aging brain the neurosurgical approach.
On the basis of our 16 years' experience, we have treated 36 patients by extrathecal shunt for idiopathic normal pressure hydrocephalus. All patients were submitted to clinical evaluation, neuroradiological, and neuropsychological (Mini Mental Test) tests. Seventy-six per cent of patients showed a significant clinical improvement. No change was found in 24% of them, including two patients who died. In a group of 13 patients we measured the level of main neurotransmitter metabolites (MHPG, HVA, 5-HIAA) in order to evaluate the functional status of encephalic monoaminergic system. If care is taken to make a correct diagnosis and give adequate treatment with a shunt, hydrocephalic dementia has a good prognosis.
Aged↗
Enzymes related to energy metabolism in human gliomas.
The evaluation of the specific activity of some enzymes related to energy transduction was performed in 7 fresh samples of malignant gliomas and in 4 samples of normal brain tissue. Compared with normal brain tissue, the hexokinase, phosphofructokinase and citrate synthase activities are lower; the lactate dehydrogenase and succinate dehydrogenase are unchanged, while glucose-6-phosphate dehydrogenase and NADP+-isocitrate dehydrogenase activities are higher in gliomas.
Brain Neoplasms↗
Spinal epidural hematoma without vertebral fracture or dislocation. Report of two cases and review of the literature.
Authors present 2 cases of spinal epidural hematoma without vertebral fracture or dislocation and review the literature. 169 fully described cases were found in literature and have been analyzed. Data confirm our opinion that the results of an early diagnosis is a better prognosis. The severity of preoperative neurological status is another important factor for the post-operative recovery, any way the absence of neurological function before the operation is not necessarily leading to a poor prognosis. Prognosis is usually poor when after the removal of the hematoma the dural pulsation is absent.
Aged↗
[Analysis of the concentration of VP 16 and VM 26 in human brain neoplasms].
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Brain Chemistry↗
[Malignant gliomas: current status and therapeutic prospectives].
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Antineoplastic Agents↗
Peripheral PICA aneurysm. Case report.
One case of aneurysm of the right distal posterior inferior cerebellar artery (PICA), arising from the telo-velo tonsillary segment, is reported; the patient, a 73 years-old woman, was successfully treated by clipping procedure. Few similar cases are reported in literature. Among all intracranial aneurysms, PICA aneurysms account for 0.5-0.7%; most of them arise from vertebro-basilar junction, while only 72 distal PICA aneurysms are reported in literature, till now, with complete anatomo-radiological study. We recommend four vessel angiography because these aneurysms are likely to be missed. When determining the surgical approach it is important to know from which segment the aneurysm arises.
Aged↗
Outcome following acute supratentorial subdural hematoma in pediatric age.
The authors report their experience in surgical treatment of 39 cases of acute subdural hematoma, followed by intensive therapy and physiokinesitherapy. The causes of head injuries, types of fractures, localization of the hematomas, concomitant lesions, diagnostic and therapeutic clinical features are discussed. The most common neurological evaluation scales for rating the state of comas are used for comparing the cases of head injury in adults (Glasgow Coma Scale) and in children (Children's Coma Scale). The Authors also report clinical follow-up, morbidity, and general mortality rate. Moreover, they emphasize the frequency and clinical importance of cases with unapparent symptomatology and demonstrate that extrinsic eye movement is a very important factor for prognostic evaluation.
Acute Disease↗
Growing skull fractures of childhood. Case report and review of 132 cases.
Authors report a case of growing skull fracture, unusual complication of linear skull fracture in infancy and childhood. A review of 132 cases reported in literature is done with an analysis of general characteristics of this lesion. The most common localization is parietal (50%); clinical presentation is represented by development of seizures (54 cases), focal neurological deficit (57 cases) or loss of consciousness (50 cases). In 50% of cases interval time between head injury and first symptom varies between 1 day and 1 year. After the first year of age the 34.4% of patients develop seizures and 59% present loss of consciousness. Among patients from 1 day to 6 months of age, 46% develop seizures, 38% focal neurological deficit and 21% loss of consciousness. Asymptomatic presentation is more common in fronto-parietal or fronto-parieto-occipital localizations. In parieto-occipital and occipital localization (30 cases), 13 patients (43.3%) have seizures, 36.7% a focal neurological deficit and 60% loss of consciousness. In parieto-temporal localization there is a higher probability of seizures (62.5%) and loss of consciousness (62.5%). The long-term follow-up and the functional recovery in patients which undergo surgery is linked to the clinical presentation and early diagnosis.
Arachnoid↗