Roberto Vagnozzi

Cerebral Oxidative Stress and Depression of Energy Metabolism Correlate with Severity of Diffuse Brain Injury in Rats

OBJECTIVE:The combined effect of traumatic brain injury (TBI) and secondary insult on biochemical changes of cerebral tissue is not well known. For this purpose, we studied the time-course changes of parameters reflecting ROS-mediated oxidative stress and modifications of cell energy metabolism determined in rats subjected to cerebral insult of increasing severity. METHODS:Rats were divided into four groups: 1) sham-operated, 2) subjected to 10 minutes of hypoxia and hypotension (HH), 3) subjected to severe diffuse TBI, and 4) subjected to severe diffuse TBI + HH. Rats were killed at different times after injury, and analyses of malondialdehyde, ascorbate, high-energy phosphates, nicotinic coenzymes, oxypurines, nucleosides, and N-acetylaspartate (NAA) were made by high-performance liquid chromatography on whole-brain tissue extracts. RESULTS:Data indicated a close relationship between degree of oxidative stress and severity of brain insult, as evidenced by the highest malondialdehyde values and lowest ascorbate levels in rats subjected to TBI + HH. Similarly, modifications of parameters related to cell energy metabolism were modulated by increasing severity of brain injury, as demonstrated by the lowest values of energy charge potential, nicotinic coenzymes, and NAA and the highest levels of oxypurines and nucleosides recorded in TBI + HH rats. Both the intensity of oxidative stress-mediated cerebral damage and perturbation of energy metabolism were minimally affected in rats subjected to HH only. CONCLUSION:These results showed that the severity of brain insult can be graded by measuring biochemical modifications, specifically, reactive oxygen species-mediated damage, energy metabolism depression, and NAA, thereby validating the rodent model of closed-head diffuse TBI coupled with HH and proposing NAA as a marker with diagnostic relevance to monitor the metabolic state of postinjured brain.

Meningiomas of the lateral ventricles. Clinical, neuroradiologic, and surgical considerations in 19 cases

The clinical and neuroradiologic findings and surgical results in a series of 19 patients with lateral ventricle meningioma, operated on during a 33-year period, are described. This experience is compared with that of previous workers and the following conclusions are drawn: these tumors have no characteristic symptoms; preoperative diagnosis requires both computed tomography scans and carotid and vertebral angiography; the safest surgical approach is through a sagittal or oblique parietooccipital cortical incision to avoid damage to motor, visual, and speech areas of the cortex.

Chronic Subdural Hematoma in Extremely Aged Patients

445 cases of chronic subdural hematomas have been operated on during the last 35 years (1951-1986). The ages of the patients ranged from 14 to 91 years and averaged 54 years. Two groups of patients were considered and compared: (A) extremely aged patients, who were over 75 years old, and (B) patients in their sixth decade of life whose age was in fact close to the mean age of chronic subdural hematoma patients in our experience. There were 35 cases (8% of the total number of cases) in group A and 113 cases (26%) in group B. Presumably etiological trauma was less severe in elderly patients who more frequently showed a background of hormonal derangement, such as liver and/or prostatic disease. Bilateral hematomas were detected more frequently in older patients. They usually presented with mental retardation, unlike younger patients who more frequently had symptoms and signs of increased intracranial pressure. Early postoperative complications occurred more frequently in older patients. However, this did not preclude obtaining good results in more than three quarters of them. The implications of these findings are discussed.

Epidermoids of the cerebellopontine angle (cpa): Usefulness of CT scan

SummaryThe AA report their experience of 8 cases of epidermoids of the cerebellopontine angle (cpa). In analyzing the various clinical, radiological and operating aspects and the results they emphasize the diagnostic pre-operative value of CT scan.

Giant aneurysm of the anterior inferior cerebellar artery simulating a cerebellopontine angle tumor

Abstract An aneurysm of the anterior inferior cerebellar artery simulating a cerebellopontine angle tumor is reported. Only 13 such cases have been published so far. The relevant literature is reviewed.

Computed tomography-guided transsphenoidal closure of postsurgical cerebrospinal fluid fistula: A transmucosal needle technique

BACKGROUNDnCerebrospinal fluid (CSF) fistula represents a fearful complication of transsphenoidal surgery and, despite careful intraoperative repair and prolonged postoperative lumbar CSF drainage, need for a new surgical intrasphenoidal plasty is not uncommon.nnnMETHODSnThese cases prompted us to develop a simple, minimally invasive, harmless repeatable technique consisting of a computed tomography (CT)-guided intrasphenoidal injection of fibrin glue through a 12-gauge spinal needle.nnnRESULTSnFive patients presenting with rhinoliquorrhea following a transsphenoidal approach for the excision of pituitary adenomas (three cases) and craniopharyngiomas (two cases) were treated successfully with the presented technique. In two cases the first attempt attained only partial success and therefore the procedure was repeated. In the last two cases, the injection of fibrin glue was preceded by 2 cc of fresh autologous blood, with the aim of enhancing the mechanisms of healing, possibly inducing adhesions and fibrosis.nnnCONCLUSIONSnThe proposed method of treatment for CSF leakage following transsphenoidal surgery may represent a valid alternative to the surgical option.

Potential risk-factors for brain-tumors in children - An analysis of 200 cases

Two hundred cases of verified brain tumors occurring in patients under 15 years of age were studied in relation to possible etiologic, genetic, and environmental risk factors. They were compared with 100 age-matched patients harboring solid neoplasms outside the nervous system, as well as with 100 normal children. In our study, first-degree relatives of a brain tumor child did not show a higher incidence of either tumors or of epilepsy and strokes as compared with controls. First-born children (46%) with higher birth weights showed a greater tendency to present brain tumors. Dystocia (18.5%), previous miscarriages (18%), and dietary restrictions during pregnancy (3%) were also noted in this study and compared with data in the literature. No evidence of a role of maternal chickenpox and toxoplasmosis could be found. The pharmacological risk also seemed to be minimal. The mothers hormonal profile is deduced from the age at menarche and delivery, as well as from a tendency to miscarriages and complicated pregnancies. With regard to the immunologic aspect, it is worth noting that 15% of the mothers complained of allergies. Live polio vaccine and zoonosis might suggest a possible role of virus-related factors in the oncogenesis of brain tumors in children. Radiation-related risk is possibly present in less than 5% of cases. Parental occupation is not relevant in this series.

Post-radiation glioma in a child

A case of primary brain neoplasm is reported that developed 11 years after prophylactic brain irradiation and intrathecal methotrexate (MTX) given for acute lymphocytic leukemia (ALL) at the age of 3 years. Cases of supposed postirradiation gliomas in children seem to have increased in recent years, particularly following apparently successful treatment for ALL or medulloblastoma. This increse might reflect the increased number of long-surviving cancer children and thus suggest that brain irradiation may be a potential risk factor in this population. After reviewing some general data on neurooncogenesis, two points are stressed: (1) the childs brain is particularly susceptible to the mutagenic effects of ionizing radiation owing to physiologically active postnatal glial cell proliferation, which takes place in the cerebral hemispheres, especially during myelinogenesis; (2) MTX could promote glial neoplasm by enhancing reparative glial cell proliferation. Prospective studies seem necessary to show whether or not prophylactic brain radiaton in ALL plays an oncogenetic role. Nevertheless, besides recurrent leukemia, leukoencephalopathy, and radionecrosis, the remote possibility of radiation-induced glial neoplasma should always be considered in cases of children treated for leukemia who present with neurological complications.