Forámenes emisarios del cráneo humano: Características anatómicas y sus relaciones con la neurocirugía clínica

The recognition of emissary foramens is important not only for understanding the regional neurovascular anatomy, but also to distinguish normal from potentially abnormal structures. Thus, the aim of this study was to review the literature on anatomical and clinical aspects of the mastoid, parietal and sphenoid emissary foramens. It was found that the emissary foramen presents importance in clinical practice because it acts as a route of spread of extracranial infection to the intracranial structures and also possible complications in neurosurgery, due to its influence in the performance of techniques such as radiofrequency rhizotomy for treatment of trigeminal neuralgia. The anatomical knowledge of the emissary foramens is important due to variability in their incidence in the human skull and its relation to the dura mater sinuses.

Relaciones entre los rotíferos, copépodos planctónicos ciclopoides y la calidad del agua en dos embalses Brasileños

Planktonic rotifers and cyclopoid copepods were studied in two reservoirs of different trophic states (eutrophic and oligo/mesoeutrophic) in the south of Brazil. During a year, monthly samplings were carried out in three stations in each reservoir. Species richness, frequency and abundance were used to find out useful and indicatives trends of water quality based on these organisms, reinforced by literature data. Species that showed higher differences between reservoirs were chosen. For Rotifera, richness, frequency and abundance of Brachionus were higher in the eutrophic reservoir, but Plationus patulus occurred only in the oligo/mesotrophic reservoir. For copepods, Tropocyclops prasinus dominated in the eutrophic reservoir, but Thermocyclops decipiens, T. minutus, T. inversus and Microcyclops anceps were dominants in the oligo/mesotrophic reservoir. In the canonical correspondence analysis, these species were indicators of the trophic state and were related with chlorophyll-a, total phytoplankton and total phosphorus. The use of these species can be efficient in the studied regions (subtropical/temperate), but comparing with other Brazilian reservoirs of tropical climate, the results could be different. Despite the dominance of T. decipiens over T. minutus, T. inversus has been widely used in Brazil as an indicator of eutrophic waters; in those cases of excessive eutrophication, other species, more rustic, commonly dominate. In the present study, Thermocyclops was dominant in the oligo/mesotrophic reservoir. The dominance of Brachionus for rotifers and Tropocyclops prasinus and Acanthocyclops robustus for copepods were indicative of eutrophic conditions.