[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Head and neck](https://durgical.com/en/anatomy/region/head-and-neck/) › Sphenoid sinus [Skeletal system](https://durgical.com/en/anatomy/system/skeletal-system/) · [Head and neck](https://durgical.com/en/anatomy/region/head-and-neck/) # Sphenoid sinus The sphenoid sinus is an air space deep in the skull base, just under the pituitary gland; surgeons pass through it to reach the pituitary from the nose. Official name: Sinus of sphenoid bone [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=head_neck&select=sphenoid_sinus&side=r) Opens in the Durgical app, no sign-up needed. ## What it is An air space in the sphenoid body, just under the pituitary. ## What it does Surgeons pass through it to reach the pituitary from the nose. ## Key points - Transsphenoidal surgery reaches the pituitary gland through the nose, the sphenoid sinus and the floor of the sella turcica - Its lateral wall bulges over the internal carotid artery and the [optic nerve](https://durgical.com/en/anatomy/optic-nerve/); the bone there can be very thin or absent, a key surgical danger - Isolated sphenoid sinusitis is uncommon but serious: deep headache, and spread to the cavernous sinus or optic nerve (visual loss, eye movement palsies) ## Key facts **Where** Body of the sphenoid, below the sella; drains to the sphenoethmoidal recess **Blood supply** Posterior ethmoidal, sphenopalatine arteries **Nerve** V1, V2 **Function** Surgical route to the pituitary ## Relations **Above** [Sella turcica](https://durgical.com/en/anatomy/sella-turcica/) with the [pituitary gland](https://durgical.com/en/anatomy/pituitary-gland/); the [optic chiasm](https://durgical.com/en/anatomy/optic-chiasm/) above and in front **Lateral** [Cavernous sinus](https://durgical.com/en/anatomy/cavernous-sinus/) with the [internal carotid artery](https://durgical.com/en/anatomy/internal-carotid-artery/) and nerves III, IV, V1, V2 and VI; the [optic canal](https://durgical.com/en/anatomy/optic-canal/) above and lateral **In front** Posterior [ethmoid cells](https://durgical.com/en/anatomy/anterior-cells-of-ethmoid-bone/) and the sphenoethmoidal recess of the [nasal cavity](https://durgical.com/en/anatomy/nasal-cavity/) **Below** Roof of the nasopharynx; the pterygoid canal with its nerve in the floor **Behind** Clivus, with the [basilar artery](https://durgical.com/en/anatomy/basilar-artery/) and [pons](https://durgical.com/en/anatomy/pons/) beyond **Medial** Intersinus septum, often off the midline and sometimes attached over the [carotid canal](https://durgical.com/en/anatomy/carotid-canal/) ## How to find it It cannot be felt. Endoscopically its ostium is found in the sphenoethmoidal recess, medial to the superior concha, close to the back of the septum. ## On imaging CT shows its pneumatisation, its septa and where they attach, and gaps in the bone over the optic nerve or internal carotid artery before surgery; MRI shows the sella, the cavernous sinus and complications of sphenoid sinusitis. ## Common problems - Sinusitis: blocked nose, thick discharge, pressure in the cheeks or teeth. - Most acute sinusitis is viral; some becomes chronic. ## How it is diagnosed Symptoms and exam; nasal endoscopy and CT for chronic or complicated cases. ## Treatment - Saline rinses, nasal steroid sprays, pain relief; antibiotics only for bacterial cases. - Endoscopic sinus surgery for chronic sinusitis. ## Clinical notes - A septum attached over the internal carotid artery can tear the artery if twisted off during surgery - Sphenoid sinusitis or a mucocele can compress the optic nerve, with visual loss - CSF leak after transsphenoidal surgery is a recognised complication, because the floor of the sella is opened ## Anatomical variants - Pneumatisation types by relation to the sella: conchal (minimal, mostly children), presellar and sellar (most adults); the sellar type gives the widest surgical access - Lateral recesses into the greater wings or pterygoid processes, and pneumatised anterior clinoid processes ## Development Tiny at birth; pneumatisation of the sphenoid body begins in early childhood and extends back under the sella through later childhood and adolescence. ## Related conditions - [Acute rhinosinusitis](https://durgical.com/en/conditions/acute-rhinosinusitis/) ## Test yourself Think of the answer, then tap the question to see it. ## Which surgical route passes through the sphenoid sinus? Transsphenoidal surgery to the pituitary gland: through the nose, the sphenoid sinus and the floor of the sella turcica. ## Which structures bulge into the lateral wall of the sphenoid sinus, and why is that dangerous? The internal carotid artery and the optic nerve; the bone over them can be very thin or absent. ## Why is isolated sphenoid sinusitis serious? It causes deep headache and can spread to the cavernous sinus or optic nerve, causing visual loss and eye movement palsies. ## Where does the sphenoid sinus drain? Into the sphenoethmoidal recess, medial to the superior concha. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/anatomy/sinus-of-sphenoid-bone/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** sinus ossis sphenoidei TA2 600 **Official Spanish (DeCS)** Seno Esfenoidal DeCS D013101 **English (TA2)** Sinus of sphenoid bone **Also called** bony sphenoidal sinus · sinus sphenoideus · sinus sphenoidalis ## Related - [Sella turcica](https://durgical.com/en/anatomy/sella-turcica/) - [Sphenoid bone](https://durgical.com/en/anatomy/sphenoid-bone/) Sources: Terminologia Anatomica (TA2); [DeCS](https://decs.bvsalud.org/es/ths/resource/?id=13485&filter=ths_termall&q=Sphenoid%20Sinus); [Anatomy, Head and Neck, Nose Paranasal Sinuses](https://www.ncbi.nlm.nih.gov/books/NBK499826/); [Anatomy, Head and Neck, Nose Sinuses](https://www.ncbi.nlm.nih.gov/books/NBK513272/). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/sinus-of-sphenoid-bone/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/sinus-of-sphenoid-bone/