Site-bond percolation in two-dimensional kagome lattices: Analytical approach and numerical simulations.

The site-bond percolation problem in two-dimensional kagome lattices has been studied by means of theoretical modeling and numerical simulations. Motivated by considerations of cluster connectivity, two distinct schemes (denoted as S∩B and S∪B) have been considered. In S∩B (S∪B), two points are connected if a sequence of occupied sites and (or) bonds joins them. Analytical and simulation approaches, supplemented by analysis using finite-size scaling theory, were used to calculate the phase boundaries between the percolating and nonpercolating regions, thus determining the complete phase diagram of the system in the (p_{s},p_{b}) space. In the case of the S∩B model, the obtained results are in excellent agreement with previous theoretical and numerical predictions. In the case of the S∪B model, the limiting curve separating percolating and nonpercolating regions is reported here.

Fourth ventricle neurocysticercosis: Rigid endoscopic management. Description of direct transcerebellar approach.

BACKGROUND: Endoscopy has gained a crucial role in high specialty neurosurgery during the last decades. At present, there are well-defined flexible neuroendoscopic procedures to treat ventricular and subarachnoid space pathologies. Neurocysticercosis is recognized as a common cause of neurologic disease in developing countries and the United States. Surgical intervention, especially cerebrospinal fluid diversion, is the key for management of hydrocephalus. In 2002, a consensus suggested that ventricular forms should be treated with endoscopy as the first option. CASE DESCRIPTION: Here, we present the case of a 51-year-old right-handed male, from Estado de México. Two days before admission he experienced holocraneal headache 7/10 on the visual analogue scale which was intermittent, with no response to any medication, sudden worsening of pain to 10/10, nausea, and vomit. On physical examination, he presented with 14 points in the Glasgow coma scale (M6, O4, V4), pupils were 3 mm, there was adequate light-reflex response, and bilateral papilledema. The cranial nerves did not have other pathological responses, extremities had adequate strength of 5/5, and normal reflexes (++/++) were noted. Neuroimaging studies showed dilatation of the four ventricles as well as a cystic lesion in the fourth ventricle. Surgical position was Concorde, and the approach through a suboccipital burr hole was planned preoperatively with craneometric points. A rigid Karl Storz Hopkins II® endoscope was inserted directly through the cerebellum and the cystic lesion was extracted entirely. CONCLUSION: This article presents a useful technique with low morbidity and mortality. Further investigation is needed, especially in our Mexico, where neuroendoscopical techniques are still in the development phase.

Camptocormia: cifosis lumbar adquirida progresiva reductible / Camptocormia: Progressive and acquired reducible lumbar kyphosis

La camptocormia es una enfermedad invalidante para el paciente que la presenta pues le limita en sus actividades de la vida diaria, así como para la marcha. Es una entidad poco frecuente, relativamente conocida, y en la que se debe pensar ante la presencia de una cifosis lumbar adquirida, progresiva y reductible en un paciente de edad avanzada. Su diagnóstico es fundamentalmente clínico y se confirma tras realización de pruebas complementarias como TAC de columna y RNM. El tratamiento en muchos casos no resulta muy efectivo y se basa en prescripción de rehabilitación, ortesis, productos de apoyo o ayudas técnicas para la marcha y tratamiento farmacológico sintomático. Presentamos el caso de una mujer de 81 a˜nos remitida desde el servicio de neurología, que fue valorada y tratada en nuestro servicio con mejoría de la clínica y de su patrón de marcha y postural (AU)

Camptocormia is a disabling disease that limits activities of daily living in affected individuals as well as their gait. It is uncommon but relatively well-known disease that should be considered in patients with progressive and reducible lumbar kyphosis acquired at advanced age. The diagnosis is mainly clinical and is confirmed by complementary tests such as spinal computed tomography and magnetic resonance imaging. Treatment is often ineffective and is based on rehabilitation, the use of orthoses, supports or technical aids for walking, and symptomatic drug therapy. We report the case of an 81-year-old woman who was referred by the neurology service and was evaluated and treated in our service. The patient showed improvements in her clinical symptoms, posture and gait (AU)

[Effect of surgery on longstanding strabismus on binocular visual evoked potential]. / Efecto de la cirugía de estrabismo de larga evolución en los potenciales evocados visuales binoculares.

PURPOSE: To analyse the effect of surgery on binocular visual evoked potential (BVEP) in adults with longstanding strabismus. METHODS: A prospective study was performed on 40 patients with a history of longstanding strabismus. Visual evoked potentials to binocular and monocular pattern reversal stimulation were recorded before surgery and 3 months after surgery. Binocular visual function was analysed by Worth and TNO tests before and after surgery. RESULTS: We did not find any differences between deviation and BVEP postoperatively (P = 0.82). The mean of BVEP and the percentage of increment of the BVEP response (10.5 and 27.14%) were larger postoperatively, than preoperatively (9.87 and 16.6%), P = 0.32 and P = 0.17, respectively. There were differences in the TNO results after surgery (P = 0.03) and when compared with postoperative deviation (P = 0.02), but not between TNO and BVEP postoperatively (P = 0.29). There were differences in the Worth results after surgery, and comparing with deviation and BVEP (P = 0.00, P = 0.01 and P = 0.07). CONCLUSIONS: Surgery in adults with longstanding strabismus could improve the deviation and seemed to improve BVEP response, but this point could not be confirmed. The results are not enough to show that the BVEP would be an objective test for binocular function evaluation, although there could be a relationship between BVEP and the TNO response.

[Painful incomplete third-nerve palsy caused by an internal carotid-communicating posterior artery aneurysm]. / Parálisis dolorosa incompleta del III nervio causada por un aneurisma de la carótida interna-comunicante posterior.

CLINICAL CASE: A 38-year-old woman presented acute-onset, painful incomplete third-nerve palsy caused by an internal carotid-posterior communicating artery (IC-PC) aneurysm. We describe the differential diagnosis with Tolosa-Hunt syndrome and the results after endovascular treatment. DISCUSSION: The presence of pupil-sparing third-nerve palsy may not exclude the presence of an IC-PC aneurysm and orbital magnetic resonance imaging and/or computed tomography imaging must be performed in these cases. The prompt recovery after endovascular treatment is consistent with previous reports.

[Conjunctival inclusion cyst after strabismus surgery by hang-back recession]. / Quiste conjuntival de inclusión tras cirugía de estrabismo según técnica de retroinserción en asa.

CASE REPORT: A 24-year-old woman, with a history of infantile esotropia and DVD operated on in infancy, had strabismus surgery performed by us. Four months later she presented with a cystic lesion that recurred after drainage and medical treatment. Complete excision of the cystic lesion was therefore performed. DISCUSSION: The epithelial cells implanted on the sclera at the time of the most recent surgery may have been the origin of inclusion cyst which developed after the strabismus surgery. This suggests a possible relationship with the scleral suture as the mechanism of cyst formation, independent of the muscle position. Complete excision is the recommended treatment for large cysts.

[Acute concomitant esotropia and hysterical amblyopia]. / Endotropía comitante aguda y ambliopía histéricas.

CASE REPORT: The authors present the case of a 26-year-old woman, in her 29th week of pregnancy, who developed intermittent esotropia and diplopia. Six months later, the process was associated with visual loss and an accommodative spasm which did not improve with cycloplegia and refraction. The symptoms remained unchanged two years later. DISCUSSION: Acute concomitant esotropia may have no obvious underlying cause, but it has been associated with disruption of fusion, myopia, neurological problems and decompensation of a pre-existing phoria or monofixation syndrome. A physical or emotional debilitating illness may precede the onset of the problem. In our case, a neurologic origin was excluded and a diagnosis of hysterical neurosis and acute concomitant esotropia with hysterical amblyopia or functional visual loss was established.

[Fracture of the proximal third of the femur. II]. / Fractura del tercio proximal del fémur (y II) postoperatorio.

The second of a two part series dealing with fractures of the femur. Postoperative health care is the focus of this article, with special attention paid to possible complications and what effect they might have on the patient's quality of life. Specific nursing care plans and procedures help prepare the patient to confront their disability in the best physical and psychological state possible.

[Fracture of the proximal third of the femur. 1. Preoperative measures]. / Fractura del tercio proximal del fémur (I). Preoperatorio.

Fractures of the proximal third of the femur occur in great numbers, especially among the over 65 population. Due to the serious nature of these injuries it is imperative that nurses have specific procedures and care plans to deal with them. The authors approach this topic in a two part series: the first part deals with the preoperative period, and the second part looks at postoperative care.

A profile of knowledge and attitudes toward tobacco usage of first and fourth year medical students at the University of Puerto Rico.

A questionnaire entitled "Attitude toward tobacco usage among health professionals in Puerto Rico" was administered to medical students completing their first and fourth years respectively at the University of Puerto Rico Medical School. Percent of each group currently smoking was found to be 18.5 and 10.8 with an average of 24.2% and 13.5% for 1st and 4th year male students and 9.1% and 3.2% for 1st and 4th year female students. A trend toward beginning smoking at an earlier age was noted as compared to a survey taken 20 years ago. Both groups demonstrated adequate knowledge of the risks and consequences of smoking, however, 4th year students had a wider awareness of smoking hazards. Attitude toward tobacco was highly dependent upon the smoking status of the respondent with non smokers being predictably more strongly opposed to tobacco usage. Although cultural differences exist between Puerto Rican and mainland health professionals, they both share similar knowledge and attitudes toward tobacco usage.