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P Rojo

Publications and source records attributed to P Rojo.

43 records · Page 3Linked to original sources
PubMedDate not supplied

[Localization of the epileptogenic zone by analysis of electroencephalographic dipole].

INTRODUCTION: In partial epilepsy with seizures which are resistant to drug treatment, better results may be obtained with surgery. This follows thorough assessment to identify the area of the brain responsible for the origin of the seizures, or the epileptogenic zone (EZ), and show that surgical operation will not cause neurological or cognitive damage which might handicap the patient. OBJECTIVE: This study analyses the value in diagnosis of electroencephalographic dipoles in delimitation of the EZ in patients with refractory partial epilepsy who are candidates for surgical treatment. PATIENTS AND METHODS: In 43 patients we made EEG recordings whilst at rest with their eyes shut during 15 minutes. The signal was analysed by digital EEG apparatus and a map drawn of cerebral electrical activity based on the maximum average amplitude of the epileptic spikes. The electric dipole equivalent to epileptiform activity between seizures was obtained using the programme for analysis of electroencephalographic sources BESA. The localization of the EZ by means of the dipole was compared with the results of EEG, MR, SPECT and seizure video-EEG using intracranial electrodes. RESULTS: The results of this study show that the dipole model used is highly sensitive for localization of EZ, and in cases in which the dipole and MR coincided, its sensitivity is similar to that of video-EEG during seizures. CONCLUSIONS: The model of dipole used in this study is of great help when indicating surgery for patients with drug-resistant epilepsy.

Anticonvulsants↗
PubMedDate not supplied

[Voltage sources analysis in studies with foramen ovale electrodes].

INTRODUCTION: Paroxysmal activity in medial temporal lobe epilepsy is originated in either hippocampal or parahippocampal regions. This activity can be directly recorded by foramen ovale electrodes. That paroxysmal activity will start from irritative or ictal areas. However, anatomo-functional relations between both regions are still debated. OBJECTIVE: We describe a new physical very simple model which allows to directly analysis the anatomo-physiological relations between sources for interictal and ictal areas. RESULTS: 1) The mathematical model allows to fit with minimum error and great precision the voltage sources originated from monopoles. 2) We can obtain this degree of precision with a matrix using an internodal distance of 0.1 mm (300x200 nodes) 3) Triplets of potentials with double sources with equal or specially with inverse charges have bigger error than monopolar charges. 4) Fitting real data obtained from a patient shows an error of 0.29 +/- 0.17% for interictal and 0.54 +/- 1.22% and 2.84 +/- 3.00% for two seizures (mean +/- SD). CONCLUSIONS: This model allows directly to know the relative anatomo-physiological relations between interictal and ictal sources in MTLE, which have a very important implications so for patho-physiological as therapeutics and outcome implications.

Action Potentials↗
PubMedDate not supplied

Subjective global assessment of nutritional status: further validation.

Subject global assessment of nutritional status was performed on 175 patients admitted to the medical-surgical gastroenterology service of a general hospital by a first-year resident and a specialist in clinical nutrition who were not aware of each other's evaluation. Patients were classified as well nourished or moderately or severely undernourished. Simultaneously, anthropometry was performed, serum albumin measured, and two units of PPD inoculated. A 79% concordance between the global subjective assessments made by the residents and the specialists was found. Patients in the three groups had significantly different weight, midarm circumference, triceps skinfold, and serum albumin values, whereas the total lymphocyte count and the percentage of negative PPD reactions were not significantly different. Subjective global assessment is a useful tool for the evaluation of nutritional status, even when used by inexperienced professionals.

Anthropometry↗