Transcribriform and transplanum endoscopic approach for skull-base tumors (original) (raw)
Related papers
The Septation of the Sphenoidal Air Sinus. A Cadaveric Study
International Journal of Morphology, 2018
The purpose of this study was to investigate the sphenoidal sinus septation in a select South African population, and document the relation of the number and location of the septa to the structures intimately related to the sinus. The intersinus and intrasinus septa of the sinus, the number and attachments of the septa were recorded from forty five cadaveric head specimens. The sphenoidal sinus intersinus septa were recorded as follows: Type 0 (absent septum) in 7.5 %, Type 1 (single septum) in 65 % and Type 2 (double septa) in 22.5 % of cases. The incidence of intersinus septa deviating to the left was prevalent; hence, the right sphenoidal sinus was dominant. The occurrence of intrasinus septa was observed in 93.3 % of cases, with a higher prevalence in males. The intrasinus septa formed cave like chambers on the sinus walls in 65.6 % cases. Incidences of the intersinus septa attaching to sella turcica (ST) (46.25 %) were prevalent compared to cases where they attached to the internal carotid artery (ICA) (6.25 %), maxillary (MN) (1.25 %) and vidian (VN) (1.25 %) nerves. However, the intrasinus septa attached more to the ICA (52.63 %) compared to their attachment to the other neurovascular structures (ST-26.32 %; MN-5.36 % and VN-2.63 %). Surgeons need to be aware of the complex anatomical variations of the sphenoidal sinus septation when performing endoscopic endonasal transsphenoidal surgeries.
Anatomic Variations of the Sphenoid Sinus and Their Impact on Trans-sphenoid Pituitary Surgery
Skull Base-an Interdisciplinary Approach, 2008
Introduction: The trans-sphenoid access to the pituitary gland is becoming the most common approach for pituitary adenomas. Preoperative evaluation of the anatomy of the sphenoid sinus by computed tomography (CT) scan and magnetic resonance imaging (MRI) is a routine procedure and can direct the surgical decision. Purpose: This work determines the incidence of the different anatomical variations of the sphenoid sinus as detected by MRI and CT scan and their impact on the approach. Methods: The CT scan and MRI of 296 patients operated for pituitary adenomas via a trans-sphenoid approach were retrospectively reviewed regarding the different anatomical variations of the sphenoid sinus: degree of pneumatization, sellar configuration, septation pattern, and the intercarotid distance. Results: There were 6 cases with conchal pneumatization, 62 patients with presellar, 162 patients with sellar, and 66 patients with postsellar pneumatization. There was sellar bulge in 232 patients, whereas this bulge was absent in 64 patients. There was no intersphenoid sinus septum in 32 patients, a single intersphenoid septum in 212 patients, and an accessory septum in 32 patients. Intraoperatively, the sellar bulge was marked in 189 cases and was mild in 43 cases. Discussion: The pattern of pneumatization of the sphenoid sinus significantly affects the safe access to the sella. A highly pneumatized sphenoid sinus may distort the anatomic configuration, so in these cases it is extremely important to be aware of the midline when opening the sella to avoid accidental injury to the carotid and optic nerves. The sellar bulge is considered one of the most important surgical landmarks, facilitating the access to the sella. The surgical position of the patient is also a crucial point to avoid superior or posterior misdirection with resultant complications. It is wise to use extreme caution while removing the terminal septum. Conclusion: Different anatomical configurations of the sphenoid sinus can seriously affect the access to the sella via the nose. The surgeon should be aware of these findings preoperatively to reach the sella safely and effectively.
Cureus
Introduction Due to the variable degree of pneumatization, the shape and size of the sphenoid sinus are irregular. An endoscopic intranasal transsphenoidal approach is made in sphenoid sinus pathologies, sphenoid sinusitis, and sellar and parasellar diseases. A diagnostic approach to the sphenoid sinus is also done to get a better MRI scan of the pituitary. The present study aims to describe the variant types of sphenoid sinus, morphometry, anatomy, and relations of sphenoid sinus, which will be helpful to surgeons during an endoscopic approach to the sphenoid sinus. Materials and methods We studied 76 cadaveric sphenoid sinuses that were exposed by taking a sagittal section of 38 formalin-fixed cadaveric heads. After examining the inter-sphenoidal septum, it was removed to observe the inside aspect of the sphenoid sinus. Different dimensions of the sinus were noted down. The bulges inside the sinus due to neurovascular structures in relation to the sinus were observed. Results The most prominent type found was the sellar in 68.4% of cases preceded by the postsellar in 23.7% of cases. Presellar type of pneumatization was seen only in 7.9% of cases and the conchal type was absent. Intersphenoid septum was seen in 92,1% of cases, out of which 11.4% of septums were deficient on the posterior aspect. An internal carotid artery bulge in the sphenoid sinus was seen in 46% of cases. In 27.6% and 19.7% of sphenoid sinuses, bulging of the optic and vidian nerves, respectively, were seen. Some of these structures were dehiscent in the sphenoid sinus. Conclusions To get more space in the sphenoid sinus, the septa in the sinus are removed by surgeons, which may damage the walls of the sphenoid sinus. Knowledge of the relations of neurovascular structures with the sphenoid sinus will be helpful to surgeons during the transsphenoidal endoscopic approach to avoid any injury to these structures.
Endoscopic anatomy of the sphenoid sinus
Journal of Laryngology and Otology, 1999
The anatomy of the sphenoid sinus, as it relates to endoscopic sinus surgery, was studied in 93 cadaver heads (186 sphenoid sinuses) using endoscopic dissections as well as sagittal sections. The relationship of the sphenoid sinuses to the carotid artery, optic nerve, floor of sella turcica, as well as other important structures, were verified and discussed. The recesses of the sinus as well as its ostium and accessory septa and crests were described and their clinical importance was discussed. Pertinent measurements were included wherever appropriate.
Otolaryngology - Head and Neck Surgery, 1999
Endoscopic surgery of the posterior ethmoid and sphenoid sinuses can present the operator with a considerable challenge. Although endoscopic training and physician experience have increased significantly in the past decade, surgical complications such as optic nerve trauma and cerebrospinal fluid leak still occur. Surgeons reporting such complications cite a lack of orientation within the dissection field as a primary cause. Because endoscopic sinus surgery is now being performed more routinely, surgical strategies designed to reduce the risk of complications are more important than ever. An anatomic landmark that could reliably orient the dissection within the posterior ethmoids and guide the surgeon to the sphenoid sinus could reduce the possibility of such adverse outcomes. In our experience identification of the superior meatus and superior turbinate provides a reliable landmark within the dissection field that can ensure surgical orientation to the operator. This technique allows safe, reliable dissection of the posterior ethmoids and an efficient approach to the sphenoid sinus, especially in patients undergoing revision surgery. In this article our technique for the identification and definition of the superior meatus and superior turbinate is presented, and the advantages of using this landmark in sinus surgery are discussed. In our experience identification of the superior meatus, superior turbinate, posterior skull base, and medial orbital wall defines a parallelogram-shaped box, which delineates the sphenoid face. This box provides the necessary orientation to guide the surgeon's entrance into the sphenoid sinus through the posterior ethmoid sinus (as Messerklinger described). Techniques for identifying the superior turbinate and meatus and for entering the sphenoid are detailed.
TURKISH JOURNAL OF MEDICAL SCIENCES
Background/aim: Because of close relations to important anatomical structures such as cavernous sinus and optic nerve, sphenoid sinus variations must be well trained by the otolaryngologist who has an interest in endoscopic sinus surgery. Newly defined sphenoseptal cell (SSC) is one of those variations that may lead to insufficient endoscopic sinus surgery outcomes if not defined preoperatively with imaging studies. The present study aimed to present the main characteristics of this special type of nasal cell. Materials and methods: In this study, 610 paranasal sinus CT scans were analyzed and reviewed retrospectively between May 2018 and December 2019. Also, endoscopic findings of SSC that cause a surgical catastrophe in identifying skull base and sella are presented during transnasal transsphenoidal pituitary surgery. Results: According to its definition and relation to the sphenoid sinus and the skull base, an SSC was seen in 21 scans of 610 patients (3.4%), 11 were women (55%) and 10 were men (45%). Conclusion: Although an SSC is a rare variation of nasal air cells, preoperative diagnosis of this cell is of paramount importance in some patients during endoscopic transnasal surgery for the identification of skull base.
The Relationship between the Variations of Sphenoid Sinus and Nasal Septum
Gulhane Medical Journal, 2014
The aim of this article is to discuss the sphenoid sinus variations that could be important for transsphenoidal pituitary surgery planning. 314 computed tomography angiography performed with 64-detector multi-slice scanner of the head and neck region in consecutive patients were studied. Thin slices axial, coronal and sagittal, maximum intensity projection and multiplanar reformatted images were obtained for detailed evaluation. 57 cases had presellar (18.2%), 40 patients had sellar (12.7%), 214 patients (68.2%) had postsellar and 3 patients (1%) had conchal pneumatization. We identified sellar bulging in 249 of 314 cases (79.3%), (43% mild, 36.3% prominent). We detected more than one septum in 107 cases (34.1%). In 4 cases (1.3%) we could not define any septum. Nasal septum was deviated to the right in 129 cases (41.1%), deviated to the left in 140 cases (44.6%) and non-deviated in 45 patients (14.3%). There was statistically significant difference in the mean distances between the deviated main sphenoid septum and the internal carotid arteries on the deviation and opposite sides. Knowing the nasal septal deviation direction does not facilitate to predict the direction of the deviation of the main sphenoid septum. Reporting important anatomical variations routinely in computed tomography and/or magnetic resonance imaging reports in transsphenoidal pituitary surgery candidates may reduce transsphenoidal pituitary surgery complications during surgery.
Endoscopic anatomy of the approaches to the sellar area and planum sphenoidale
Arquivos de Neuro-Psiquiatria, 2011
The productive work between otolaryngologists and neurosurgeons has resulted in the emergence of endoscopic endonasal skull base surgery. The goal of the present study is to describe the endoscopic anatomy of the endonasal approach to the sellar region and planum sphenoidale, highlighting the key points of the surgical approach and the neurovascular landmarks. Method: Descriptive study of the endoscopic endonasal dissection of 9 fresh cadavers with exposure of the anatomic structures. Results: The endoscopic endonasal ethmoidectomy and sphenoidotomy allows an expanded access to the sellar area and planum sphenoidale. The surface anatomy of the sphenoid sinus is easily identifiable and provides safe landmarks, guiding the intracranial dissection. Conclusion: The endoscopic endonasal approach to the skull base by the ENT and neurosurgeon is feasible, but it requires adequate anatomical knowledge and endoscopic skills for its realization, which can be obtained by practicing in cadavers.
Endoscopic anatomy of sphenoid sinus for pituitary surgery
Clinical Anatomy, 2008
Endoscopic endonasal transsphenoidal approach to the sellar region yields an alternative to classical microsurgical approaches. Endoscopes provide images that differ from microscopic view. This study aimed to highlight surgical landmarks and their anatomical relationships for pituitary surgery through endoscopic perspective. Ten sides of five adult cadaveric heads with red-colored latex injected arteries were evaluated. Endoscopic dissections were performed and measurements were done in the sphenoid sinuses before and after the removal of bony structures in all the aspects. Endoscopic vision of the sellar region enabled a wide panoramic perspective and detailed inspection. The measurements, in general, indicated the variations in the bony structures and soft tissues. The width of the pituitary, which is the distance between the medial margins of the carotid prominences, was measured as 21 6 2.5 mm and the distance between the medial margin of the carotid prominences at the lower margin of the pituitary was 18 6 3.1 mm. After the bony structures were removed, further measurements were done. The width of the pituitary, which is the distance between the medial margins of the anterior curvature of the ICA, was measured as 23.2 6 3 mm, while the distance between the posterior curvature of the ICA was 19.7 6 4.9 mm. Endoscopic view provided superior detailed visualization of the close relationships between pituitary gland, internal carotid arteries, and optic nerves. This facilitated exact evaluation for variations, which could result in more effective and safe surgery. However, these variations again emphasize the necessity of preoperative radiological evaluation in each case. Clin. Anat. 21:627-632, 2008. V V C 2008 Wiley-Liss, Inc.