scholarly journals Posterior ethmoidal foramen

2016 ◽  
Author(s):  
Henry Knipe ◽  
Amit Chacko
2011 ◽  
Vol 30 (5) ◽  
pp. E5 ◽  
Author(s):  
Emel Avcı ◽  
Erinç Aktüre ◽  
Hakan Seçkin ◽  
Kutluay Uluç ◽  
Andrew M. Bauer ◽  
...  

Object Although craniofacial approaches to the midline skull base have been defined and surgical results have been published, clear descriptions of these complex approaches in a step-wise manner are lacking. The objective of this study is to demonstrate the surgical technique of craniofacial approaches based on Barrow classification (Levels I–III) and to study the microsurgical anatomy pertinent to these complex craniofacial approaches. Methods Ten adult cadaveric heads perfused with colored silicone and 24 dry human skulls were used to study the microsurgical anatomy and to demonstrate craniofacial approaches in a step-wise manner. In addition to cadaveric studies, case illustrations of anterior skull base meningiomas were presented to demonstrate the clinical application of the first 3 (Levels I–III) approaches. Results Cadaveric head dissection was performed in 10 heads using craniofacial approaches. Ethmoid and sphenoid sinuses, cribriform plate, orbit, planum sphenoidale, clivus, sellar, and parasellar regions were shown at Levels I, II, and III. In 24 human dry skulls (48 sides), a supraorbital notch (85.4%) was observed more frequently than the supraorbital foramen (14.6%). The mean distance between the supraorbital foramen notch to the midline was 21.9 mm on the right side and 21.8 mm on the left. By accepting the middle point of the nasofrontal suture as a landmark, the mean distances to the anterior ethmoidal foramen from the middle point of this suture were 32 mm on the right side and 34 mm on the left. The mean distance between the anterior and posterior ethmoidal foramina was 12.3 mm on both sides; the mean distance between the posterior ethmoidal foramen and distal opening of the optic canal was 7.1 mm on the right side and 7.3 mm on the left. Conclusions Barrow classification is a simple and stepwise system to better understand the surgical anatomy and refine the techniques in performing these complex craniofacial approaches. On the other hand, thorough anatomical knowledge of the midline skull base and variations of the neurovascular structures is crucial to perform successful craniofacial approaches.


1997 ◽  
Vol 273 (2) ◽  
pp. R661-R668 ◽  
Author(s):  
C. S. Ignacio ◽  
P. E. Curling ◽  
W. F. Childres ◽  
R. M. Bryan

Although perivascular nerves containing nitric oxide synthase (NOS) have been anatomically described for rat cerebral arteries, a dilator function for these nerves has eluded investigators when using isolated vessels. Rat middle cerebral arteries (MCAs) were isolated, pressurized, and electrically stimulated. The resting diameter of the MCAs after pressurization was 233 +/- 4 microns (n = 17) in one study. The MCAs showed a frequency-dependent dilation when stimulated. Maximum dilation (25-30% increase in diameter) occurred at a frequency of 8-16 Hz. Removal of endothelium or glibenclamide (10(-5) M), a blocker of ATP-sensitive potassium channels, had no effect on the dilations. The dilations were completely blocked with NG-nitro-L-arginine methyl ester (L-NAME) (10(-5) M), a general NOS inhibitor, and cold storage (24 h). The inhibition by L-NAME could be reversed by the addition of 10(-8) M L-arginine, the active precursor of NOS. Furthermore, 7-nitroindazole (10(-4) M), an inhibitor specific for the neuronal isoform of NOS, reduced the dilations by 43% (P < 0.05). Transections of nerve bundles originating from the sphenopalatine ganglia at the ethmoidal foramen blocked the dilations produced by electrical stimulations. We conclude that rat cerebral arteries have functionally intact perivascular nerves that dilate by releasing nitric oxide.


2014 ◽  
Author(s):  
Craig Hacking ◽  
Prashant Mudgal

2021 ◽  
Vol Publish Ahead of Print ◽  
Author(s):  
Daniele Gibelli ◽  
Michaela Cellina ◽  
Stefano Gibelli ◽  
Chiara Floridi ◽  
Giovanni Termine ◽  
...  

1995 ◽  
Vol 15 (3) ◽  
pp. 525-531 ◽  
Author(s):  
Neil M. Branston ◽  
Atsushi Umemura ◽  
Achamma Koshy

In two groups of normotensive rats anaesthetised with halothane, either the nasociliary nerve (NCN) or the NCN and parasympathetic (PS) fibres together (NCN-PS) were functionally blocked at the right ethmoidal foramen. Blocking was achieved reversibly and repeatedly using a cooling probe. Cortical regional CBF (rCBF) was measured bilaterally using laser–Doppler probes. In Group 1, bilateral common carotid occlusion (CCO) was applied for 1 min both with and without block. In Group 2, CCO was applied permanently followed by stages of controlled haemorrhagic hypotension to deepen the ischaemia and the block applied at each stage. In Group 1, during CCO, rCBF was unaffected by blocking NCN-PS. However, during the transient postocclusive hyperaemia, blocking NCN-PS, but not NCN alone, significantly increased right side rCBF. In Group 2 and in Group 1 in the absence of CCO (normotension), rCBF was unaffected by blocking either set of fibres. We conclude that neither NCN nor PS fibres contribute to the tonic level of rCBF or to its autoregulatory control, but PS fibres conduct impulses tending to resolve postischaemic hyperaemia. We suggest that a subpopulation of PS fibres containing neuropeptide Y is activated under conditions of supernormal rCBF.


2016 ◽  
Vol 6 (1) ◽  
pp. 20-25
Author(s):  
Shilpa N Gosavi ◽  
Surekha D Jadhav ◽  
Balbhim R Zambare

Las órbitas óseas son cavidades del esqueleto situadas a cada lado de la nariz. Se conocen las diferencias raciales en las medidas orbitales. El objetivo del presente estudio era determinar las distancias de varias fisuras y foramen en la órbita en relación a ciertos puntos de referencia óseos / quirúrgicos sobre los márgenes orbitales en la población india, lo que puede ser útil durante la cirugía orbital. La distancia de canal óptico (OC), fisura orbitaria superior (SOF), fisura orbital inferior (IOF) y forámenes lagrimales (LF) se mide a partir de puntos de referencia como cresta lacrimal anterior (ALC) para la pared medial, muesca/foramen supra orbital (SN) para la pared superior, sutura  cigomática frontal (FZ) de la pared lateral y un punto en el margen inferior (OIM) justo encima del agujero infraorbitario. Se midió  la distancia del foramen etmoidal anterior y posterior (AEF y PEF) de ALC. Se observó la presencia de foramen etmoidal media (MEF) y forámenes lagrimales (LF).La distancia media de OC fue 39,71 ±2,67 mm(deALC), 45,11 ±3,4 mm(de SN) , 48,32 ±2,8 mm(de FZ ) y 45,97 ±3,9 mm(de  OIM). La distancia segura para el nervio óptico para cada pared orbital se calcula restando5 mmde la distancia más corta medida. The bony orbits are skeletal cavities located on either side of the nose. Racial differences in orbital measurements are known. The aim of the present study was to determine the distances of various fissures and foramen in the orbit with reference to certain bony / surgical landmarks on the orbital margins in Indian population which can be useful during various surgical procedures. The distance of optic canal (OC), superior orbital fissure (SOF), inferior orbital fissure (IOF), lacrimal foramen (LF) were measured from landmarks like anterior lacrimal crest (ALC) for medial wall, supraorbital foramen/ notch (SON) for superior wall, fronto-zygomatic suture (FZ) for lateral wall and a point on inferior margin (IOM) just above the infraorbital foramen. Distance of anterior and posterior ethmoidal foramen (AEF and PEF) from ALC was measured. The incidence of middle ethmoidal foramen (MEF) and lacrimal foramen (LF) was noted. The mean distance of OC was 39.71 ±2.67 mm(from ALC), 45.11 ±3.4 mm(from SN), 45.97 ±3.9 mm(from FZ) and 48.32 ±2.8 mm(from IOM). The safe distance for optic nerve for each orbital wall was derived by subtracting5 mmfrom the shortest measured distance.


2005 ◽  
Vol 56 (suppl_4) ◽  
pp. ONS-406-ONS-410 ◽  
Author(s):  
Daniel V. White ◽  
Eric H. Sincoff ◽  
Saleem I. Abdulrauf

Abstract OBJECTIVE: Vascular lesions of the anterior cranial fossa can receive significant blood supply from the anterior ethmoidal artery. Embolization of this blood supply exposes the parent vessel, the ophthalmic artery, to possible embolic complications, which can lead to loss of vision. A study of the microsurgical anatomy can help delineate the course of the anterior ethmoidal artery and find the best points for proximal control of the blood supply to these lesions. Clinical cases are presented to illustrate how lesions with prominent anterior ethmoidal artery feeders are best approached through fronto-orbital single-flap craniotomies. METHODS: Eight cadaveric dissections to demonstrate the microsurgical anatomy of the anterior ethmoidal artery were performed to study the relevant anatomy. Two clinical cases are presented that demonstrate clinical application of this anatomy through fronto-orbital single-flap craniotomies. RESULTS: Eight arteries were studied in four cadaveric heads. The dissections show the course of the anterior ethmoidal artery from the ophthalmic artery in the orbit, through the anterior ethmoidal foramen into the ethmoid air cells, to the cribriform plate, where it turns superiorly to become the anterior falx artery. The first surgical case is of a giant tuberculum sellae meningioma that was resected with coagulation and division of the anterior ethmoidal arteries at the anterior ethmoidal foramina at the laminae papyraceae of both medial orbital walls. The second surgical case is of a large deep right frontal arteriovenous malformation that was resected with coagulation and division of the anterior ethmoidal artery at the anterior ethmoidal foramen of the lamina papyracea of the right medial orbital wall. CONCLUSION: The cadaveric dissections and our surgical experience show that the anterior ethmoidal artery has three important sites for surgical access: 1) the anterior ethmoidal foramen at the lamina papyracea of the medial orbital wall; 2) the anterior ethmoid canal at the lateral ethmoid wall; and 3) extradurally, at the cribriform plate. These three sites are best accessed through a fronto-orbital single-flap craniotomy, which can be unilateral or bilateral, depending on the pathological findings. The described orbital-cranial approach in this article is not being advocated to replace the standard pterional and frontal approaches; rather, we suggest it as an option in these complex cases that require early proximal control of the anterior ethmoidal artery feeders.


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