The pterygopalatine ganglion, palatine nerves and vessels: dissection and pathway / El ganglio pterigopalatino, nervios palatinos y vasos: disección y trayecto

SUMMARY: Background and Objectives: The palatine nerves and vessels cross the pterygopalatine fossa, the palatine canals, the palatine foramina and the submucosal space, at the level of the hard palate and the palatine recess of the maxillary sinus. Their trajectory is long, complicated and difficult to highlight on a single dissection piece. In the literature that we studied, we did not find clear images that fully highlight the real configuration of the pterygopalatine ganglion and nerves and of the palatine vessels. Our aim was to provide a clear and representative dissection of the pterygopalatine ganglion and of the palatine neurovascular bundle throughout its pathway in a simple, coherent and useful presentation for the practitioners interested in the regional pathology. We resected the posterior and inferomedial osseous walls of the maxillary sinus and highlighted the neurovascular structures in the pterygopalatine fossa and the wall of the maxillary sinus. We photographed the dissection fields and detailed the important relations. The images that we obtained are clear, simple and easy to interpret and use. We successfully highlighted the aspect and the main relations of the pterygopalatine ganglion and the pathway and distribution of the palatine nerves and vessels, from their origin to the terminal plexuses. There is a broad spectrum of clinical procedures or situations that require a proper knowledge and understanding of the anatomical pathway and relations of the palatine neurovascular elements. This includes the various types of regional anesthesia, tumor resection surgery, flaps of the palatine mucosa, the LeFort osteotomy etc. Demonstration of the pterygopalatine ganglion and its relations is useful in endoscopic interventions at the level of the pterygopalatine fossa.

RESUMEN: Los nervios y vasos palatinos atraviesan la fosa pterigopalatina, además de los canales palatinos, los forámenes palatinos y el espacio submucoso a nivel del paladar duro y el receso palatino del seno maxilar. Su trayectoria es larga, complicada y difícil de destacar en una sola pieza de disección. En la literatura que estudiamos, no encontramos imágenes claras que resalten completamente la configuración real del ganglio y los nervios pterigopalatinos y de los vasos palatinos. Nuestro objetivo fue proporcionar una disección clara y representativa del ganglio pterigopalatino y del haz neurovascular palatino a lo largo de su trayecto en una presentación simple, coherente y útil para los médicos interesados en la patología regional. Resecamos las paredes óseas posterior e inferomedial del seno maxilar y resaltamos las estructuras neurovasculares en la fosa pterigopalatina y la pared del seno maxilar. Fotografiamos los campos de disección y detallamos las relaciones importantes. Las imágenes que obtuvimos son claras, sencillas y de fácil interpretación. Resaltamos con éxito el aspecto y las principales relaciones del ganglio pterigopalatino y el trayecto y distribución de los nervios y vasos palatinos, desde su origen hasta los plexos terminales. En conclusion, existe un amplio espectro de procedimientos o situaciones clínicas que requieren un adecuado conocimiento y comprensión del trayecto anatómico y las relaciones de los elementos neurovasculares palatinos. Esto incluye los distintos tipos de anestesia regional, cirugía de resección tumoral, colgajos de mucosa palatina, osteotomía de LeFort, etc. La demostración del ganglio pterigopalatino y sus relaciones es útil en intervenciones endoscópicas a nivel de la fosa pterigopalatina.

The Sympathetic and Parasympathetic Contributions to the Cardiac Plexus: a Fetal Study / Contribuciones Simpáticas y Parasimpáticas al Plexo Cardíaco: Estudio Fetal

The cardiac plexus is formed by sympathetic nerves originating from the superior, middle, inferior cervical or cervicothoracic ganglia as well as from the first to the fifth thoracic ganglia. Furthermore, the vagus nerve and its counterpart, the recurrent laryngeal nerve supply the cardiac plexus with parasympathetic cardiac nerves. This investigation aimed to review and record the medial contributions of the cervical ganglia, first to fifth thoracic ganglia and medial contributions of the vagus and recurrent laryngeal nerves to the cardiac plexus. The study involved bilateral micro-dissection of forty cadaveric fetal specimens (n=80). The origins of sympathetic contributions to the cardiac plexus were described as either ganglionic, inter-ganglionic or from both the ganglion and the inter-ganglionic sympathetic chain. The number of cervical sympathetic ganglia varied from two to five in this study; the superior cervical ganglion was constant while the middle cervical, vertebral, inferior cervical or cervicothoracic ganglia were variable. The prevalence of cardiac nerves were as follows: superior cervical cardiac nerve (95%); middle cervical cardiac nerve (73%); vertebral cardiac nerve (41%); inferior cervical cardiac nerve (21%) and cervicothoracic cardiac nerve (24%). This investigation records the thoracic caudal limit of the thoracic sympathetic contributions to the cardiac plexus as the T5 ganglion. The findings of this study highlight the importance of understanding the medial sympathetic contributions and their variations to the cardiac plexus as this may assist surgeons during minimal access surgical procedures, sympathectomies, pericardiectomies and in the management of diseases like Raynaud's Phenomenon and angina pectoris.

El plexo cardíaco está formado por los nervios simpáticos procedentes de los ganglios cervicales superior, medio e inferior o cervicotorácico, así como los ganglios torácicos desde el primero al quinto. Por otra parte, el nervio vago y su contraparte, el nervio laríngeo recurrente suministra al plexo cardíaco nervios cardíacos parasimpático. Esta investigación tuvo como objetivo revisar y registrar las contribuciones mediales de los ganglios cervicales, ganglios torácicos del primero al quinto ganglios y contribuciones mediales de los nervios laríngeos recurrentes y vagos en el plexo cardíaco. Se realizó la micro-disección bilateral de cuarenta especímenes cadavéricos fetales (n = 80). Los orígenes de las contribuciones simpáticas hacia el plexo cardíaco se describen de forma independiente como ganglionar o inter-ganglionar, o desde ambos ganglios y la cadena simpática interganglionar. El número de ganglios simpáticos cervicales varió de dos a cinco; el ganglio cervical superior fue constante, mientras que los ganglios medio-cervical, vertebral, cervical inferior o cervicotorácico fueron variables. La prevalencia de los nervios cardíacos fueron: nervio cardíaco cervical superior (95%); nervio cardíaco cervical medio (73%); nervio cardiaco vertebral (41%); nervio cardíaco cervical inferior (21%) y nervio cardíaco cervicotorácico (24% ). La investigación registró el límite torácico caudal de las contribuciones torácicas simpáticos al plexo cardíaco como el ganglio T5. Los resultados de este estudio muestran la importancia de comprender las contribuciones simpáticas mediales y sus variaciones en el plexo cardíaco, ya que podrían ayudar a los cirujanos durante los procedimientos quirúrgicos mínimanente invasivos, simpatectomías, pericardiectomías y en el manejo de enfermedades como el fenómeno de Raynaud y la angina de pecho.

Anatomic variation of cranial parasympathetic ganglia

Having broad knowledge of anatomy is essential for practicing dentistry. Certain anatomical structures call for detailed studies due to their anatomical and functional importance. Nevertheless, some structures are difficult to visualize and identify due to their small volume and complicated access. Such is the case of the parasympathetic ganglia located in the cranial part of the autonomic nervous system, which include: the ciliary ganglion (located deeply in the orbit, laterally to the optic nerve), the pterygopalatine ganglion (located in the pterygopalatine fossa), the submandibular ganglion (located laterally to the hyoglossus muscle, below the lingual nerve), and the otic ganglion (located medially to the mandibular nerve, right beneath the oval foramen). The aim of this study was to present these structures in dissected anatomic specimens and perform a comparative analysis regarding location and morphology. The proximity of the ganglia and associated nerves were also analyzed, as well as the number and volume of fibers connected to them. Human heads were dissected by planes, partially removing the adjacent structures to the point we could reach the parasympathetic ganglia. With this study, we concluded that there was no significant variation regarding the location of the studied ganglia. Morphologically, our observations concur with previous classical descriptions of the parasympathetic ganglia, but we observed variations regarding the proximity of the otic ganglion to the mandibular nerve. We also observed that there were variations regarding the number and volume of fiber bundles connected to the submandibular, otic, and pterygopalatine ganglia.

Distribuiçäo topográfica dos neurônios intracardíacos em feto e recém nascido / Topographic distribution of intracardiacs neurons in fetal and newborn

A fim de possibilitar estudos comparativos do SNAIC, procuramos estabelecer a distribuiçäo topográfica dos neurônios, em coraçöes de feto e recém-nascido, segundo limites anatômicos bem definidos. O trabalho foi dividido em 2 etapas. Na primeira, que foi uma etapa auxiliar, verificamos a distribuiçäo geral das células ganglionares nos átrios e ventrículos e o diâmetro médio dos neurônios em 11 coraçöes. Na segunda analisamos, quantitativamente, em 3 coraçöes, a distribuiçäo topográfica dessas células. Concluímos o seguinte: 1. A inclusäo e cortes seriados de todo ou de grande parte do coraçäo de feto e recém-nascido constituiu metodologia útil para o estudo topográfico e contagem de neurônios intracardíacos. 2. Os neurônios, dispostos em gânglios e ocasionalmente como células isoladas, localizavam-se predominantemente no subepicárdio, menos comumente no miocárdio e, raramente, no subendocárdio. Näo foram observados nas aurículas. 3. As células ganglionares geralmente eram uninucleadas, mas apresentaram, ocasionalmente, até 4 núcleos. 4. O diâmetro neuronal variou com a idade gestacional, característica importante para se estabelecer a metodologia para sua contagem. 5. Das 18 áreas por nós identificadas, duas (áreas 1 e 2) eram mais ricas em neurônios e tinham limites anatômicos bem definidos. 6. A área 1, que inclui o nó SA, apresentou a maior quantidade de neurônios (32 por cento). 7. A área 2 continha aproximadamente 12 por cento da populaçäo neuronal analisada e, por ser pouco extensa, permite contagem neuronal menos trabalhosa que a área 1. 8. A área 18, que inclui o nó AV, era pobre em neurônios.

Estudo anatômico e quantitativo do gânglio pterigopalatino humano. Morfometria e estereologia / Anatomic and quantitative study of the human pterygopalatine ganglion. Morphometry and stereology

The pterygopalatine ganglion is important in the regulation of the intraocular pressure and in the cerebral vasodilatation connected with headache of vascular origin. Four human ganglia were dissected, fixed in formalin and serially sectioned with a 6 microns thickness. The volume of the ganglion was calculated by point-counting and stereological parameters were determined using the test-system M42 with light microscopy. The PG volume was (mean +/- standard error of the mean) 5.6 +/- 0.5 mm3. The volume density of neurons was 51.1% +/- 3.4%, and the unitary volume of the neurons was 41,200.0 +/- 2,250.0 microns. The numerical density was 12,600.0 +/- 677.0 neurons by mm3, therefore approximately 70,560 neurons by ganglion.

Morfología y conexiones del ganglio de Meckel / Morphology and conections of Meckel's ganglia

Se hace un estudio macroscópico de la morfología y conexiones del ganglio de Meckel en 40 hemicabezas teniendo como base la disección hecha bajo la lupa anatómica con iluminación. Se dan detalles de su forma, ubicación y abordaje, recalcando sus conexiones con el nervio esfenopalatinos y ramo orbitario