Pituitary surgery
Michael Y. Wang, Andrea L. Strayer, Odette A. Harris, Cathy M. Rosenberg, Praveen V. Mummaneni in Handbook of Neurosurgery, Neurology, and Spinal Medicine for Nurses and Advanced Practice Health Professionals, 2017
The nasal cavity provides access to this space, because the sphenoid bone connects it to the pituitary gland above. The carotid arteries are in close relationship to the sphenoid bone, creating an impression in the lateral wall of the sphenoid sinus. Also, both cavernous sinuses lie laterally to the sphenoid bone. The pituitary gland rests in the center of the bone, the sella turcica, limited anteriorly by the tuberculum sellae and posteriorly by the dorsum sellae. The sphenoid sinus is an air cavity inside the sphenoid body. It separates the cavernous sinuses, the cavernous segments of the carotid arteries, the optic, extraocular, and trigeminal nerves, and the pituitary gland from the nasal cavity (Figure 37.4). The sella turcica is separated from the rest of the brain by the diaphragma sellae, a membrane that covers the pituitary gland, except for a small opening in its center for the pituitary stalk.
Pituitary Tumors and Their Management
Demetrius Pertsemlidis, William B. Inabnet III, Michel Gagner in Endocrine Surgery, 2017
Transsphenoidal surgery is unique in neurosurgery in that the operating surgical corridor is narrow, limiting the surgeon’s view. In addition, during tumor removal only a fraction of the tumor can be visualized, which makes the confirmation of complete tumor removal often difficult. The indications for the use of endoscopic transsphenoidal surgery are essentially the same as for the standard approach. Endoscopic surgery through use of the short focal length offers the advantages of enhanced illumination and a wider angle of viewing than the microscope. The tumor morphology often dictates the approach in each case. Tumors with extensive suprasellar extension may require a craniotomy rather than a transsphenoidal resection. In addition to a detailed history, physical, and endocrinological workup, the use of high-resolution MRI with and without contrast is imperative before surgery. Special coronal sella windows help delineate the sella anatomy, especially the location of the carotid arteries and the optic chiasm. The extent of sphenoid sinus pneumatization is also important when planning the appropriate surgical approach. Many endoscopic surgeons also favor high-resolution computed tomography of the sphenoid and sella to better assess the bony anatomy of the sphenoid.
Traumatic CSF rhinorrhea
Jyotirmay S. Hegde, Hemanth Vamanshankar in CSF Rhinorrhea, 2020
The firm adherence of the dura to the anterior skull base makes it a more common site for leaks than the middle or posterior skull base.7 The cribriform plate, being thin and fragile, is covered only by the arachnoid layer. Small fractures here easily violate the arachnoid layer in the absence of the dura. Also, the cribriform is located in the midline, below the slight medial curve of the floor of the skull base, causing CSF to gravitate to this area.8 Sphenoid sinus (30%), frontal sinus (30%) and cribriform/ethmoid (23%) form the most common areas of leaks. However, when endoscopic surgical trauma is considered, ethmoid/cribriform (80%), frontal sinus (8%), and sphenoid sinus (4%) are the most common sites (Figure 5.1 A, B). Sphenoid sinus is the most common site after neurosurgical trauma. Temporal bone fractures can lead to CSF otorrhea and rhinorrhea.7 72% of temporal bone fractures lead to CSF rhinorrhea, according to Brodie and Thompson.9
An unusual case of a grade I meningioma with perineural spread
Published in British Journal of Neurosurgery, 2023
Mohammed Fadelalla, Avinash Kumar Kanodia, John Brunton, Kirit Singh, Antonia Torgersen, Esther Sammler, Colin Smith, David Mowle, Paul White, Kismet Hossain-Ibrahim
Head Computerized Tomography (CT) (Figure 1) showed a subtle soft tissue prominence in the right parasellar region and mucosal thickening/soft tissue in the sphenoid sinus on the right side. There was also subtle asymmetry in the region of the pterygopalatine fossa with poorly seen fat on the right side. The changes were initially thought to be inflammatory of sphenoid sinus origin. Magnetic Resonance Imaging (MRI) (Figures 2 and 3) showed homogenously enhancing bilateral parasellar masses with encasement of the Internal Carotid Arteries (ICA) and narrowing of the right ICA. There was anterior extension of the tumour on the right side into the orbital apex and perineural spread along the right maxillary nerve and bilateral mandibular nerves with an associated focal mass below the skull base on left side along the course of the mandibular nerve. The soft tissue mass in the right side of the sphenoid sinus was again identified. There were several dural based enhancing lesions elsewhere suggestive of meningiomas but the perineural spread was considered distinctly unusual and raised the possibility of tumours such as adenoid cystic carcinoma, squamous cell cancers, metastases or inflammatory conditions. CT of the chest, abdomen and pelvis were normal as was MRI of the spine.
Neuro-Ophthalmic Literature Review
Published in Neuro-Ophthalmology, 2018
David Bellows, Noel Chan, John Chen, Hui-Chen Cheng, Peter MacIntosh, John H. Pula, Michael Vaphiades, Konrad P Weber
The authors report a retrospective evaluation spanning ten years. They describe cases of sphenoid sinus disease having neuro-ophthalmologic manifestations. They excluded describing non-inflammatory cases such as malignancy, and they excluded any cases wher pathology was localized anywhere outside the sphenoid sinus. In all, they found 67 cases of isolated sphenoid sinus disease, although only 23 were included in the report. It would have been helpful if they reported why the other cases were not included, but it is possible these were the non-inflammatory cases. The authors noted that neuro-ophthalmologic manifestations are non-specific, and include optic neuropathy, third nerve, and sixth nerve palsy. Fungal sinusitis was the most common diagnosis where post-operative pathology differed from preliminary radiographic diagnosis. Sphenoidotomy with drainage was the main treatment in all patients, and the authors recommend NOT treating with steroids until the infectious lesion is cleared. They found patients with diplopia responded much better to treatment than patients with optic neuropathy.
Evaluation of nasal function after endoscopic endonasal surgery for pituitary adenoma: a computational fluid dynamics study
Published in Computer Methods in Biomechanics and Biomedical Engineering, 2022
Miao Lou, Luyao Zhang, Simin Wang, Ruiping Ma, Minjie Gong, Zhenzhen Hu, Jingbin Zhang, Yidan Shang, Zhenbo Tong, Guoxi Zheng, Ya Zhang
The original images were imported into MIMICS software (Materialise, Leuven, Belgium) for image segmentation and primary smoothing to reconstruct the airway structure. Due to the minimal influence of the paranasal sinuses on airflow, they were not included in the reconstruction of the models, except for the sphenoid sinus which was relevant to the present study. Thus, to create the preoperative model, the nasal cavity, pharynx, and sphenoid sinus were analyzed. EEA surgery was performed virtually on the preoperative model, from which 6 postoperative models were constructed using 6 variations of tissue excision: 1) EEA with small posterior septectomy (0.5 cm, sPS), 2) middle posterior septectomy (1.5 cm, mPS), 3) large posterior septectomy (2.5 cm, lPS), and 4) EEA with sPS and left middle turbinate resection (sPS-MTR), 5) mPS-MTR, and 6) lPS-MTR. Anterior inferior sphenoid sinus wall resection (approximately 1.5 cm in diameter) was performed in all six postoperative models. The effect of MTR and PS on nasal structure of typical sections were shown in Figure 1D.
Related Knowledge Centers
- Maxillary Nerve
- Ophthalmic Nerve
- Paranasal Sinuses
- Sphenoid Bone
- Nasal Cavity
- Sella Turcica
- Body of Sphenoid Bone
- Sphenoethmoidal Recess
- Choana
- Posterior Ethmoidal Nerve