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Background: The intracranial migration of a ventriculoperitoneal shunt (VPS) has been previously described, it is a very rare event, and the mechanisms of this migration have not yet been elucidated. Case Description: Newborn at 38 weeks of gestation by cesarean section, with congenital hydrocephalus due to Dandy–Walker malformation that required right Frazier VPS placement. At 2-month follow-up, computed tomography of the skull showed cranial migration of VPS and dysfunction. At evaluation, there were signs of systemic infection. External ventricular drainage was placed and an intravenous antibiotic scheme for Gram-positive bacteria was started. After 3 months, cerebrospinal fluid cultures were negative and definitive VPS was decided. Conclusion: Different possible mechanisms have been proposed, such as negative intraventricular pressure, positive intra-abdominal pressure, use of valveless catheters, excessive burr hole size, as well as such as occipital ventricular access, thin cortical mantle, incorrect distal and proximal fixation, short distance between the peritoneum and ventricles, and a possible inflammatory reaction to the catheter material (silicone). A combination of these different mechanisms contributes to proximal shunt migration. Although the placement of a VPS is a procedure well taught since the 1st years of neurosurgical residency, it is not exempt from complications. Although, as was previously stated in this paper, the incidence of a complete cranial VPS migration is extremely rare, and only a few cases are documented, it is still important to report this type of cases and to try to elucidate the possible mechanisms involved.

El ser humano logra la estabilidad necesaria para poder desempeñar eficientemente las actividades comunes de la vida diaria mediante el sistema vestibular y su constante comunicación con múltiples sistemas, principalmente con el sistema óculo-motor y el sistema propioceptivo. Actualmente y con aumento en su incidencia las consultas por síntomas vestibulares juegan un papel importante en la actividad laboral del otorrinolaringólogo, sumándole a esto la dificultad que existe para corroborar el diagnóstico de una manera objetiva. Se han descrito históricamente múltiples técnicas para evaluar el sistema vestibular en respuesta a un esfuerzo por hacer un mejor diagnóstico y tratamiento de estas lesiones entre las que se encuentra el estudio del Potencial Evocado Miogénico Vestibular (VEMP). El VEMP es una metodología de estudio relativamente nueva, descrita por primera vez como método de evaluación de la función vestibular en la década de los noventa por Colebatch y cols. Es una prueba no invasiva, de bajo costo, fácil y rápido de realizar, transformándose en una herramienta clínica muy útil en la verificación de patologías del laberinto posterior, complementando la exploración otoneurológica tradicional. En el presente trabajo de revisión se exponen generalidades, definición, historia, fundamento fisiológico, métodos y aplicaciones clínicas de los VEMP.

During the Cenomanian–Turonian transition interval, larger benthic foraminifera became extinct or suffered decreases in terms of their diversity. Anoxic/dysoxic conditions of oceanic bottom water masses and potentially seawater acidification during this pivotal time also affected ecological niches in the shallow epeiric domain and resulted in the demise of many taxa of benthic foraminifera worldwide. Nevertheless, exceptions to this pattern have been reported too. Here, evidence is presented for mass occurrences of larger benthic foraminifera (Perouvianella peruviana) from the Western Platform in Peru that were not affected by environmental conditions related to the Cenomanian–Turonian transition. A new architectural analysis of P. peruviana tests found in abundance in central Peru has permitted a detailed update on its systematic and functional morphology. The paleoenvironment associated with the P. peruviana mass occurrence was characterized by mesotrophic conditions, perhaps in one way or another similar to the environmental parameters that lead to Aptian and Albian larger benthic foraminifera mass occurrences at the southern Tethyan margin (‘Orbitolina levels’). Algae and small, cosmopolitan r-strategist foraminifera coexisted with P. peruviana. Moreover, a first description of the soritid taxa Pseudopeneroplis oyonensis n. gen., n. sp. is provided. Interestingly, the superposition of local and global environmental patterns onto the Western Peruvian shelf water masses triggered a mass development of the Perouvianella population coincident with Oceanic Anoxic Event 2. Conversely, the migration of foreign complex-shelled K-strategist larger benthic foraminifera from neighboring realms was inhibited.

Research regarding child support typically focuses on the effects of child support awards and its underlying principles within child support models. However, researchers have invested little effort in the analysis of child support guideline comparisons or in the development of analyses to determine whether state adopted guidelines seem reasonable based on state-specific macroeconomic variables. This analysis intends to develop a model to determine the reasonableness of child support guidelines for states that use the income shares method based on the net income of both parents. Further, it intends to suggest that the development of a standard model is possible and, to a certain extent, needed, to obtain interstate uniformity. Findings suggest that the implementation of such a model could lead to more equitable and uniform basic child support awards.