The sphenoidal emissary foramen and the emissary vein: Anatomy and clinical relevance.

Although the sphenoidal emissary foramen (SEF) and its content are anatomically and clinically relevant, accurate description of them in the modern literature is lacking. This study aimed to examine and describe the SEF and its content (the sphenoidal emissary vein [SEV]). We analyzed 1,000 computed tomography (CT) images, 170 dry skulls, 50 formalin-fixed specimens, and three specimens (heads) following guidelines proposed by Dr. Albert L. Rhoton Jr. MD for latex injection. SEV morphology was determined by histological staining and electron microscopy. The SEF was observed in 46.8% of the CTs studied (25.4% bilateral and 21.4% unilateral), and 45.2% of the dry skulls (18.8% bilateral and 26.4% unilateral). In 9.5% of CTs and 21.1% of dry skulls there was a blind channel in the external surface of the cranial base; since there was no communication with the cranial cavity, it was not considered as the SEF. During the dissections, the SEF was found in seven individuals. In three of them, the SEV was an alternative route for venous drainage of the venous plexus of the foramen ovale. Its walls were composed of collagen fibers and its endothelium contained rhomboid cells resembling those commonly found in the superior sagittal sinus. The presence of the SEF and SEV can anatomically explain the spread of certain cranial base pathologies from or toward Meckel's cave or the cavernous sinus, and should be taken into account during procedures in the middle cranial fossa, percutaneous approaches, odontological procedures, and treatment of dural arteriovenous fistulas. Clin. Anat., 33:767-781, 2020. © 2019 Wiley Periodicals, Inc.

Cisto nasolabial bilateral: relato de dois casos / Bilateral nasolabial cyst: report of two cases

O cisto nasolabial caracteriza-se como lesão não-odontogênica de partes moles, rara e com ocorrência em situação paramediana, anteriormente ao rebordo alveolar da maxila e à asa do nariz. Portratar-se de lesão de tecido mole, geralmente não produz alteração radiográfica. No presente trabalho são descritos dois casos de cisto nasolabial, nos quais são evidenciados aspectos relevantes em relação ao diagnóstico diferencial por meio de tomografia computadorizada e ressonância magnética, bem como os aspectos atípicos encontrados em um dos casos relatados, como bilateralidade e diferença de intensidade de sinal à ressonância magnética. São discutidos, ainda, fatores determinantes para o diagnóstico diferencial de lesões de tecido mole do complexo maxilofacial,como cistos fissurais de ocorrência central (sagital), entre eles dermóides, palatinos e nasopalatinos (cisto do canal do incisivo), e cistos de fissura lateral.

The nasolabial cyst is defined as nonodontogenic soft tissue lesion, rare and with occurrence in sagittal plane, between midline and nasal cartilage. Because its soft tissue composition, there is no radiographic presentation in conventional radiographic examination,being indicated evaluation through computed tomography and magnetic resonance imaging. In the present study, two cases are discussed, being one in white female subject, 72-year-old, and other in a black male subject, 24-year-old. The authors discuss about relevant aspects related to differential diagnosis through computed tomography and magnetic resonance imaging, as wellas atypical features founded in one of the cases, like bilateral occurrence with different signal intensity in magnetic resonance imaging and determinant factors for differential diagnosis of softtissues pathologies of maxillofacial complex, as fissure cysts with central occurrence (sagittal cysts), as dermoid cysts, palatine and nasopalatine and lateral fissure cysts.