Biomedical subjects

G Torrealba

Publications and source records attributed to G Torrealba.

At least 19 recordsLinked to original sources

PubMed2001

[Spinal cord metastasis: an uncommon location. Experience in 2 cases].

Spinal cord metastases are an uncommon secondary location of a malignant neoplasm. They are rarely diagnosed during life and when that is the case, it is in the clinical setting of a disseminated cancer and very seldom as the first clinical manifestation. We report two patients, with no previous disease, who developed a progressive myelopathy. An intramedullary spinal cord tumor was diagnosed, based on the clinical picture and imaging studies. They were operated and biopsies showed spinal cord metastases whose primary tumor was a lung neoplasm. We discuss the clinical features in these patients, the diagnosis of progressive myelopathy in cancer patients, treatment and prognosis of this unusual secondary cancer location.

Adenocarcinoma, Clear Cell↗

PubMed2000

Temporal lobe epilepsy surgery with limited resources: results and economic considerations.

This study evaluates the surgical outcome of patients with medically refractory temporal lobe epilepsy (TLE) who underwent anterior temporal lobe lobectomy (ATL) based on data derived from noninvasive studies and assesses the economic costs entailed at a newly created epilepsy program in Chile. Seventeen ATL candidates underwent a presurgical evaluation. This included outpatient brain MRI and neuropsychological testing and inpatient scalp/sphenoidal prolonged video-EEG monitoring. There were 10 females and 7 males, with a mean age of 23.8 years and a mean duration of seizure disorder of 12 years. Patients with congruent data localizing the seizure focus to one anterotemporal region underwent ATL. Seven patients underwent a left-side ATL and 10 patients a right-side ATL. The histopathological findings showed a low grade tumor in six patients, hippocampal sclerosis in five, neuronal migration disorder in four, and cavernous angiomas in two patients. The mean follow-up period was 29.1 months. Seizure outcome was assessed with Engel's classification: class I, no seizures or only auras; class II, rare seizures; class III, >90% seizure reduction; class IV, <90% seizure reduction. Fifteen patients are now in class I, one patient in class II, and one in class IV. The total cost, including evaluation and surgery, was equivalent to US$ 5,020. Thus, well-selected TLE patients can derive maximal benefit from ATL after a noninvasive presurgical evaluation. This finding is of great significance for the creation of epilepsy surgery programs in developing countries.

Adult↗

PubMed1998

[Cerebral metabolic monitoring experience in critical neurological patients].

BACKGROUND: Cerebral metabolic monitoring in critical neurological patients allows the assessment of neuronal tissue response to injury and to plan the best therapy to correct each critical brain situation. AIM: To evaluate the usefulness of cerebral metabolic monitoring in patients with acute cerebral injury. PATIENTS AND METHODS: A retrospective analysis of 29 patients with acute brain injury, in whom a catheter was located in the bulb of the jugular vein to perform a cerebral metabolic monitoring. These patients were compared with others that were not subjected to this monitoring. The evolution at six months of follow up was assessed using the Glasgow outcome score, considering a favorable evolution when this score was 4 or greater. RESULTS: Patients with an hyperemic state on admission or after optimization of therapy did not have hospital mortality, and 73% had Glasgow outcome score of 4 or greater at six months of follow up. On the other hand, 50% of those with hypoperfusion or global ischemia died during hospitalization and 72% had a Glasgow outcome score of 3 or less at six months. Patients not subjected to cerebral metabolic monitoring behave as those with hypoperfusion or global ischemia. CONCLUSIONS: Cerebral metabolic monitoring is an useful tool to optimize the management of patients with acute cerebral injury, and those patients with an hyperemic cerebral state have the best prognosis.

Adolescent↗

PubMed1992

Meningothelial meningioma with "amianthoid" fibers. Case report with ultrastructural study.

The case of a meningothelial meningioma with 'amianthoid' fibers in a 48-year-old woman is presented. By light microscopy the tumor showed the typical features of meningothelial meningioma and rounded, deeply eosinophilic, and fibrillary areas, especially around and/or in the vicinity of blood vessels. These fibers are also called 'amianthoid' fibers. Ultrastructurally, these foci were made up of disorderly arranged and interwaving mature collagen fibrils with a variable width between 40 and 190 nm. No evidence of intracellular collagen synthesis by the tumor cells was found. The presence of 'amianthoid' fibers does not seem to carry any prognostic significance.

Collagen↗

PubMed1992

[Foramen ovale electrodes in the study of temporal lobe epilepsy].

Corticograms of the mesial structures of the temporal lobe may be obtained with the recently developed foramen ovale electrodes. Since their installation is easy and of low risk, they will probably displace other invasive techniques routinely used up to the moment for the localization and lateralization of epileptic foci originated in the temporal lobe. For the first time in our country, we have used this technique in 7 patients with medically intractable complex partial epilepsy. In all the patients, the study allowed to clear doubts about the laterality of the start of ictal activity and to define irritative foci not found with conventional continuous superficial electroencephalographic recordings. The procedure was uneventful and the implanted electrodes were optimally tolerated. Foramen ovale electrodes are an effective diagnostic method for temporal lobe epilepsies and their features are specially appropriate for our milieu.

Adolescent↗

PubMed1990

[The value of cerebral biopsy in patients with AIDS and extensive cerebral lesions].

We performed cerebral biopsy in 4 patients with AIDS and evidence of expanding intracerebral lesions. Three patients had cerebral toxoplasmosis and the fourth had Chagas encephalitis. No patient developed complications. We feel that cerebral biopsy is warranted and safe in patients with AIDS and intracerebral lesions of uncertain origin.

AIDS Dementia Complex↗

PubMed1988

Reflex effects evoked by stimulation of hypoglossal afferent fibers.

In pentobarbitone-anesthetized cats, electrical stimulation of the central ends of the main trunks of transected hypoglossal nerves evoked vascular (pressor or depressor) reactions, mydriasis, slow and deep breathing, and reflex activation of laryngeal and facial muscles. Stimulation of the central end of the transected ramus descendens hypoglossi also provoked reflex contraction of cricothyroideus. These reflexes may be elicited also after intracranial section of hypoglossal nerve roots, but not after intracranial section of ipsilateral vagal roots. The above reflexes were abolished by acute section of the ipsilateral hypoglossonodosal branch, but they may be reproduced by electrical stimulation of the central end of this anastomotic branch between hypoglossal nerve and nodose ganglion. Stimulation of the central end of one transected hypoglossus evoked reflex efferent discharges in contralateral hypoglossus and contraction of contralateral tongue muscles. Stimulation of the central end of one transected hypoglossal end-branch inhibited efferent discharges in another end-branch. The crossed hypoglossohypoglossal reflex and the ipsilateral reflex inhibition were abolished by section of the hypoglossonodosal branch or vagal roots at the stimulated side. We conclude that reflexes evoked by stimulation of peripheral hypoglossal nerve in cats are mediated by afferent fibers directed to the nodose ganglion and entering the brain stem via vagal roots.

Afferent Pathways↗

PubMed1987

Nimodipine-treated subarachnoid hemorrhage associated with acute pseudo-obstruction of the colon.

Nimodipine is being used with increasing frequency in the prevention or treatment of vasospasm due to subarachnoid hemorrhage. Few side effects have been described. An acute pseudo-obstruction of the colon (Ogilvie's syndrome) in a patient treated with an intravenous infusion of nimodipine is reported. The possible relationship between this serious complication and the use of this drug is discussed.

Acute Disease↗

PubMed1987

Protracted vomiting as the presenting sign of posterior fossa mass lesions.

Four patients with mass lesions of the posterior fossa experienced protracted vomiting as their only symptom for extended periods of time. The responsible lesions were a cerebellar tumour in two patients, a ventricular cysticercus in one patient, and a giant vertebral artery aneurysm in another. All four cases had compression or displacement of the floor of the fourth ventricle, where the "vomiting centre" has been located. The value of vomiting as a sign of a posterior fossa lesion is emphasised.

Adult↗

PubMed1986

Cerebellar medulloblastoma: results of multidisciplinary treatment. Report of 120 cases.

The authors report a series of 120 cerebellar medulloblastomas. All patients were operated on between 1953 and 1982. Among them, 88 completed the treatment with radiotherapy, and 32 had additional chemotherapy. The operative mortality was 22.5%. The 5-year survival rate was 30% in the whole series. Recurrences occurred in 35 patients, associated with supratentorial or spinal metastasis in 60% of cases.

Adolescent↗

PubMed1984

Cysticercosis of the central nervous system: clinical and therapeutic considerations.

In a group of forty cases of cysticercosis of the central nervous system, 59% presented with intracranial hypertension due to obstructive hydrocephalus. Ventricular or cisternal cysts, and chronic cysticercus meningitis were the most common causes of hydrocephalus. Seizures occurred in 40% of the patients, in one-half of them in association with CT-detected parenchymatous cysts. In 20% of the cases progressive mental deterioration was the main clinical feature, at times associated with hydrocephalus. CT scan provided the highest diagnostic yield, being abnormal in 90% of cases. Long term prognosis was poor, with a mortality rate of 38% over a 40-month follow-up period. The most common cause of death (60%) was meningitis. CSF shunting is the treatment of choice for hydrocephalus, irrespective of its mechanism. Surgical resection is indicated in some cases with a single superficial (cortical) or posterior fossa cyst. Supratentorial cysts carry a relatively benign prognosis.

Adolescent↗

PubMed1983

Axonal transport dysfunction in dystrophia myotonica.

Axonal transport of acetylcholinesterase (AChE) was measured in the median and sural nerves of a subject who suffered from dystrophia myotonica and in a control subject. It was found that the basal activity of AChE was increased in myotonic nerves while its proximodistal transport was inhibited.

Acetylcholinesterase↗

PubMed1980

[Cerebral vasospasm. Clinicoangiographic correlation].

The authors analyzed the clinicoangiographic correlation of cerebral vasospasm in a series of 120 cases of subarachnoid hemorrhage due to aneurysmal rupture. They made such correlation in the pre and postoperative course, in the follow-up, and in relation with the pathological findings. All patients were studied with one to three angiographies in the pre and postoperative course. For the clinical grading the authors have used the classification of Botterell modified by Hunt et al, and for the cerebral vasospasm, the classification of Pool and Potts and Saito et al. They found a good correlation between the cerebral vasospasm and the disorders of consciousness or motility, i.e. when both of them are considered separately, and only in patients with neurological injury. In comparing Botterell grade I and grades II-V, in 25% of the grade I patients, cerebral vasospasm was observed without neurologic injury. The incidence of cerebral vasospasm was lower in grades II-V patients and the severity of the clinical picture was in relation with other factors such as hematoma, infarct, hydrocephalus, etc. The authors consider the possibility of a personal variability of the cerebral vasospasm in relation with a different susceptibility to the spasmogenic substances.

Adolescent↗

PubMed1976

The third ventricle. Normal anatomy and changes in some pathological conditions.

An anatomical study of the normal anterior inferior part and the floor of the third ventricle has been made and its radiological appearance shown. Specimens and casts were analyzed and correlated with ventriculograms using watersoluble contrast media. The detailed appearance of the optic recess and sulcus of Monro, which has not been well described in the neuroradiological literature, is illustrated and detailed. The changes in the optic recess in hydrocephalus are discussed. Deformities of the different segments of the floor as a result of tumors of the posterior fossa and hydrocephalus are shown.

Cerebral Ventricle Neoplasms↗

PubMed1973