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S J Zinreich - One of the best experts on this subject based on the ideXlab platform.
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relationship of the optic nerve to the posterior paranasal Sinuses a ct anatomic study
American Journal of Neuroradiology, 1996Co-Authors: Mark C Delano, F Y Fun, S J ZinreichAbstract:PURPOSE To delineate the relationship between the optic nerves and the posterior paranasal Sinuses using CT data. METHODS Direct coronal Sinus CT scans of 150 consecutive patients with chronic inflammatory Sinus disease were reviewed by two radiologists. Axial oblique reconstructions along the course of the optic nerve were obtained for the first 100 patients. The direct relationship between the optic nerve and the posterior ethmoid and Sphenoidal Sinuses was recorded, as were identations into the Sinus wall, course of the nerve through the Sinus region, pneumatization of the anterior clinoid process, and bone dehiscence. RESULTS The relationship of the optic nerve to the posterior paranasal Sinus fell into one of four discrete categories, type 1 through type 4. All 300 nerves were intimately related to the Sphenoidal Sinus. A small minority (3%) were in contact with the posterior ethmoidal Sinus. Only type 4 nerves had contact with the posterior ethmoid air cell. Type 1 nerves course adjacent to the sphenoid Sinus without indentation of the wall (228 nerves, 76%). Type 2 nerves course adjacent to the Sphenoidal Sinus, causing indentation of the Sinus wall (44 nerves, 15%). Type 3 nerves course through the sphenoid Sinus (19 nerves, 6%). Type 4 nerves course immediately adjacent to the Sphenoidal Sinus and the posterior ethmoidal air cell (9 nerves, 3%). Bone dehiscence over the optic nerve was found in 24% of the nerves; 4% of the optic nerves in our study had an associated pneumatized anterior clinoid process and 77% of these had an associated dehiscence over the optic canal. CONCLUSIONS In all our cases the course of the optic nerve was adjacent to the Sphenoidal Sinus. Only 3% were in contact with the posterior ethmoidal Sinus. Anatomic configurations that predispose the optic nerve to injury include type 2 or 3 optic nerves, bone dehiscence over the nerve, and pneumatization of the anterior clinoid process. These configurations are common and should be routinely sought out so that devastating complications from Sinus surgery can be avoided.
Alessandra Alfieri - One of the best experts on this subject based on the ideXlab platform.
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endoscopic endonasal cavernous Sinus surgery an anatomic study
Neurosurgery, 2001Co-Authors: Alessandra AlfieriAbstract:OBJECTIVE: The endoscopic surgical anatomy of the cavernous Sinus was studied to establish an anatomic basis for endoscopic endonasal cavernous Sinus surgery. METHODS: Five adult cadaveric heads were studied with 0-, 30-, and 70-degree 4-mm rod-lens endoscopes. The posterior wall of the Sphenoidal Sinus was approached via a paraseptal, middle turbinectomy, or middle meatal approach. RESULTS: The posterior bony wall of the Sphenoidal Sinus is subdivided into five vertical compartments: midline, bilateral paramedian, and bilateral lateral. The midline vertical compartment consists of the planum Sphenoidale, tuberculum sellae, sella, and clival indentation. The paramedian vertical compartment is composed of the medial third of the optic canal and the carotid artery protuberance. The lateral vertical compartment contains four bony protuberances (optic, cavernous Sinus apex, maxillary, and mandibular) and three depressions (carotico-optic, ophthalmomaxillary [V1-V2], and maxillomandibular [V2-V3]). The three depressions form anatomic triangles at the lateral vertical compartment: the optic strut triangle, which is bordered by the optic nerve, carotid artery, and oculomotor nerve (IIIrd cranial nerve); the V1-V2 triangle; and the V2-V3 triangle. The internal carotid artery at the posterior wall of the Sphenoidal Sinus can be subdivided into two main segments: the parasellar and the paraclival. The vidian canal is a landmark that leads to the foramen lacerum, the mandibular nerve, and the pterygopalatine fossa. CONCLUSION: Endoscopic anatomy of the cavernous Sinus has been studied via an endonasal route in cadaveric specimens to provide an anatomic basis for endoscopic endonasal cavernous Sinus surgery.
B Petruson - One of the best experts on this subject based on the ideXlab platform.
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nitric oxide production in the Sphenoidal Sinus by the inducible and constitutive isozymes of nitric oxide synthase
Rhinology, 2005Co-Authors: Karin Petruson, J Stalfors, K E Jacobsson, B PetrusonAbstract:Objective To study the production of nitric oxide (NO), and the presence of different isoforms of the NO-synthesising enzyme, NO-synthase (NOS), in the paranasal Sinus. Materials and methods Ten patients, undergoing surgery for pituitary adenoma, were examined for the presence of NO gas in the Sphenoidal and maxillary Sinus. The distribution of different NOS isozymes in mucosal biopsies from sphenoid and maxillary Sinus and ethmoidal cells was studied. Results The mean concentration of NO was 2575 ppb in the Sphenoidal Sinus and 6792 ppb in the maxillary Sinus. Morphological analyses revealed intense NADPH-diaphorase staining throughout the epithelium. Immunoreactivity against NOS2 (inducible NOS) was observed in the apical cell layer but not of the basal layer. NOS1 (neuronal NOS)-immunoreactivity was mainly seen in the subapical part of the epithelium and NOS3 (endothelial NOS)-immunoreactivity was observed only in the most apical part of the epithelium. Conclusion NO concentration in the Sphenoidal Sinus is about the same as in the nasal cavity and approximately half of the concentration found in the maxillary Sinus. All of the three main different isozymes of NOS can be demonstrated in the mucosa of the Sphenoidal and maxillary Sinus and ethmoidal cells, NOS2 being the most abundant isoform.
M Pinget - One of the best experts on this subject based on the ideXlab platform.
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Sphenoidal Sinus mucocele after transSphenoidal surgery for acromegaly
Neurosurgical Review, 1999Co-Authors: L Kessler, V Legaludec, Jean Louis Dietemann, Daniel Maitrot, M PingetAbstract:This report concerns one case of a sphenoid Sinus mucocele occurring 17 years after transSphenoidal surgery for acromegaly. In 1979, a 51-year-old man was successfully operated by the transnasal transSphenoidal approach for a growth hormone (GH) adenoma 1 cm in diameter. In 1996, the patient was hospitalized for headaches and diplopia. He presented a loss of right visual acuity with paralysis of the right oculomotor nerve. The basal GH level was normal with a satisfactory decrease after oral glucose ingestion. Pituitary sellar radiography showed a disappearance of the posterior clinoid while magnetic resonance imaging revealed the existence of a bilocular, circular, homogeneous lesion of the sphenoid Sinus 3 cm in diameter with a posterior and lateral extension. The diagnosis of mucocele was confirmed by surgical treatment, allowing drainage of the mucocele through a transSphenoidal approach. The drained material was composed of Sinus epithelium containing many polynuclear and resorptive cells. Postoperatively, the symptoms decreased dramatically, leading to full recovery of visual function and disappearance of the headaches. Apart from the tumor recurrence, the mucocele of the sphenoid Sinus can be evoked as a possible long term complication of transSphenoidal sugery for pituitary adenoma.
Mark C Delano - One of the best experts on this subject based on the ideXlab platform.
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relationship of the optic nerve to the posterior paranasal Sinuses a ct anatomic study
American Journal of Neuroradiology, 1996Co-Authors: Mark C Delano, F Y Fun, S J ZinreichAbstract:PURPOSE To delineate the relationship between the optic nerves and the posterior paranasal Sinuses using CT data. METHODS Direct coronal Sinus CT scans of 150 consecutive patients with chronic inflammatory Sinus disease were reviewed by two radiologists. Axial oblique reconstructions along the course of the optic nerve were obtained for the first 100 patients. The direct relationship between the optic nerve and the posterior ethmoid and Sphenoidal Sinuses was recorded, as were identations into the Sinus wall, course of the nerve through the Sinus region, pneumatization of the anterior clinoid process, and bone dehiscence. RESULTS The relationship of the optic nerve to the posterior paranasal Sinus fell into one of four discrete categories, type 1 through type 4. All 300 nerves were intimately related to the Sphenoidal Sinus. A small minority (3%) were in contact with the posterior ethmoidal Sinus. Only type 4 nerves had contact with the posterior ethmoid air cell. Type 1 nerves course adjacent to the sphenoid Sinus without indentation of the wall (228 nerves, 76%). Type 2 nerves course adjacent to the Sphenoidal Sinus, causing indentation of the Sinus wall (44 nerves, 15%). Type 3 nerves course through the sphenoid Sinus (19 nerves, 6%). Type 4 nerves course immediately adjacent to the Sphenoidal Sinus and the posterior ethmoidal air cell (9 nerves, 3%). Bone dehiscence over the optic nerve was found in 24% of the nerves; 4% of the optic nerves in our study had an associated pneumatized anterior clinoid process and 77% of these had an associated dehiscence over the optic canal. CONCLUSIONS In all our cases the course of the optic nerve was adjacent to the Sphenoidal Sinus. Only 3% were in contact with the posterior ethmoidal Sinus. Anatomic configurations that predispose the optic nerve to injury include type 2 or 3 optic nerves, bone dehiscence over the nerve, and pneumatization of the anterior clinoid process. These configurations are common and should be routinely sought out so that devastating complications from Sinus surgery can be avoided.