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N Arriada-Mendicoa

Publications and source records attributed to N Arriada-Mendicoa.

10 recordsLinked to original sources
PubMed2003

Is it healthy to be chaotic?

The concept of Chaos has proven to be one of the greatest scientific advances that have led to radical philosophical implications. It deals with dynamic systems whose determining factors are completely unknown to us. Sometimes it seems that these dynamic systems exhibit a stochastic behavior while others portray simpler or better known behaviors where determinism is obvious. When the physician faces chaotic, dynamic systems, he or she wonders if it is healthy for these biologic systems to be chaotic. When analyzing the variation in brain and heart rates mathematically, the conclusion is that these rates are chaotic, complicated and unpredictable. Because each organ regulates its own performance, the mathematical variations seem to be the result of the organ's determinism rather than fluctuation. This healthy variability is neither a random nor an uncontrolled fluctuation. It is a certain, well-harmonized chaos, that 'provides the body with the flexibility to respond to different stimuli'.

Animals↗
PubMed2002

Simultaneous treatment of a pituitary adenoma and an internal carotid artery aneurysm through a supraorbital keyhole approach.

We describe a case in which an incidental left carotid aneurysm was found during the preoperative evaluation of a pituitary adenoma. After magnetic resonance imaging (MRI) and angiography delineated their characteristics, we chose to treat both lesions simultaneously through a left supraorbital keyhole approach. The aneurysm clipping was followed by intracapsular resection of the tumor that was identified later as a non-secretory adenoma. The postoperative course was uneventful. This case shows that in carefully selected patients it is possible to treat successfully concurrent conditions through a minimally invasive approach, with the well known advantages of low morbidity and a short hospital stay.

Adenoma, Chromophobe↗
PubMed1998

Juvenile familial amyotrophic lateral sclerosis: four cases with long survival.

Four cases are reported of juvenile familial amyotrophic lateral sclerosis (JFALS) with exceptionally long survival (mean=27 years), and consequent development of dementia. Subjects' mean age at onset was 15.7 years. Their clinical features and electrophysiological findings support the diagnosis. One subject's MRI scan showed severe atrophy to the cortex and brain stem; wallerian degeneration in the pyramidal pathway, as reported in other studies, could not be found. JFALS is characterized by the involvement of other neuronal systems not present in the adult form and by long survival after disease onset.

Adolescent↗
PubMed1997

Optic neuritis progressing to multiple sclerosis.

We report a partially retrospective and longitudinal study of patients with optic neuritis (ON) that developed multiple sclerosis (MS). We assessed clinical features or factors that might differentiate these patients from those with ON that did not develop MS. Of the cases followed, 110 (67%) were found to have an idiopathic origin of the disease; whereas 55 (33%) were found to develop it secondary to another disease. Of the 110 idiopathic cases, 13 (12%), developed MS over an average of 2 years. The results of these patients in the laboratory analyses of blood and CSF as well as the results of the MRI and evoked potential studies, were significantly different from the ON patients without MS. We conclude that the percentage of patients with ON in our sample that developed MS is similar to that found in Japan and is relatively low in comparison to other reports.

Adult↗
PubMedDate not supplied

[Current concepts regarding the cerebellum and cognition].

OBJECTIVE: To review the main cognitive processes regulated by the cerebellum and the anatomical circuits involved in their clinical correlation. DEVELOPMENT: The cerebellum is generally regarded as a regulator of motor function with a key role in movement coordination. Clinical evidence of the relation of the cerebellum to neural functions typically considered as cortical, is supplied by several neuropsychological alterations detected in both degenerative disorders and acute insult to the region such as vascular event and surgery. More anatomical circuits between the cerebellum and several cortical areas and limbic system, with the ventral pons region as main afference and efference relay of all these pathways. Cerebellar structures that are phylogenetically older such as the floculonodullar lobe, vermix, fastigial nuclei and globus nuclei have a tight relationship to emotional control and autonomic manifestations. More complex circuits are founded in the regulation of learning, motor planning and language. Functional imaging studies have helped to confirm the relationship between the cerebellum and memory processes, finding a selective activation of lateral regions during to cerebellar damage, such a frontal like syndromes, memory deficits and aphasia and even though dysmetria with incoordination between mental process velocity and its motor execution. CONCLUSIONS: All the data from clinical and functional studies indicate that the cerebellum has a central co-ordinating function not only of movement but also regulating thought. The cerebellum should, therefore, be reconsidered as a complex neurone system at much the same level as the more advanced cortical structures.

Cerebellum↗
PubMedDate not supplied

[Attention deficit syndrome. Basic aspects of its diagnosis and treatment].

INTRODUCTION: The attention deficit syndrome is one of the commonest behavior disorders of infancy, although it is considerably underestimated. DEVELOPMENT: The aetiology of attention deficit syndrome is multifactorial since genetic, environmental, nutritional and psychosocial factors have been found to be associated with its development. Diagnosis depends mainly on the identification of behavior changes especially of inattention, impulsiveness and hyperactivity: it should be made at home and at school and based on the exclusion of severe organic and neurological disorders which also present initially with similar characteristics. Electrophysiological studies may be useful since multiple electroencephalographic changes have been reported, as have prolonged latency of III and V waves of brain stem evoked potentials, The best management requires educational therapy combined with controlled medical treatment. Use of stimulants should be carefully considered and the tricyclic drugs are preferably the first pharmacological option. CONCLUSIONS: Current findings regarding the repercussions of attention deficit syndrome in adults shows the need for early diagnosis and treatment of the condition so as to avoid severe personality disorders including antisocial and criminal behavior. It is essential that the parents and the child himself understand the condition in order to achieve satisfactory results of long term treatment.

Attention Deficit Disorder with Hyperactivity↗
PubMedDate not supplied

[Minimally invasive surgery in intracranial aneurysms].

INTRODUCTION: The use of minimally invasive procedures in neurosurgery permits a significant reduction in peri-operative morbidity and duration of hospital stay. The fronto-latero-basal (FLB) approach gives good exposure of the structures of the anterior and middle fossas with access to most aneurysms of the anterior circulation, thus avoiding extensive craniotomies and the use of brain retractors. OBJECTIVE: We present an analysis of 27 patients operated on to clip 29 aneurysms of the anterior circulation using the FLB approach. PATIENTS AND METHODS: The study included 27 patients, 18 women and 9 men with an average age of 47.53 years. On clinical staging, using the Hunt and Hess scale, 12 patients were between 0 and 1, 8 at stage II, 6 at stage III and 1 at stage IV. RESULTS: The aneurysms were mainly on the internal carotid artery (16), middle cerebral artery (5), anterior communicating artery (5) and bifurcation of the carotid and middle cerebral arteries (3). The surgical operation lasted an average of 166.15 minutes; it was possible to clip the artery in 28 cases (96.5%). Two patients died (of renal failure and of disseminated intravascular coagulation). Most patients were discharged with a score of 5 points on the Glasgow prognosis scale 7.6 days after operation. CONCLUSIONS: Use of minimally invasive procedures such as FLB gives optimal functional and aesthetic results, with the advantage of being possible using the basic instruments available in any neurosurgical department, without depending on advanced technology.

Adult↗
PubMedDate not supplied

[Chronic hydrocephaly in adults. A diagnostic and therapeutic challenge].

OBJECTIVE: To describe the main clinical features of the different conditions which present as chronic hydrocephaly, emphasising the diagnosis and treatment. DEVELOPMENT: In the study of any dementia syndrome, normotensive hydrocephaly (HN) is of particular interest since this condition may be treated and cured. However, prediction of which cases will benefit from surgery is one of the most important aspects of diagnosis. The development of paraclinical investigations of the dynamics of cerebrospinal fluid (CSF) has led to great advances in the management of these chronic forms of hydrocephaly, since they are the best parameters for prognosis when deciding whether to insert a by pass. The treatment of post traumatic hydrocephaly has also benefited from these studies, since the cases of simple atrophy may now be distinguished from those which follow a clinical course similar to HN. Recently, two types of hydrocephaly have been identified as being very different from the typical forms. These are external hydrocephaly, in which CSF accumulates in the convexity of the cerebral hemispheres, and long term ventriculomegaly, in which severe ventricular dilation is accompanied by cognitive alterations and features of acute hydrocephaly. CONCLUSIONS: Treatment of each of these conditions is a challenge. Therefore careful analysis of the clinical features, imaging studies and CSF dynamics is essential when deciding whether or not to use by pass treatment.

Adult↗
PubMedDate not supplied

Frequency of motor neuron diseases in a Mexico City referral center.

OBJECTIVE: To analyze the incidence and clinical characteristics of MND (Motor Neuron Diseases) in a Mexican institution. MATERIAL AND METHODS: It was a retrospective study, of 274 definitive MND patients seen in a neurological reference hospital of Mexico City during the period of 1965-1995 (248 as Amyotrophic Lateral Sclerosis, 15 as Progressive Bulbar Palsy, 8 as Primary Lateral Sclerosis and 3 as Progressive Spinal Atrophy). RESULTS: The frequency of MND increased gradually in our institution in the 31 years revised. The mean age of onset in our series was approximately 48 years in contrast to a higher age found in other series. The clinical features are similar to those found elsewhere. CONCLUSIONS: Our study showed that the frequency of MND is increasing in Mexico in a similar fashion to that observed in the rest of the world. This makes conceivable that the incidence of MND in Mexico may also resemble the figures reported worldwide. Prospective population studies are required to establish the incidence of MND in Mexico.

Adult↗