The human skull contains many anatomical features. Among these is a small, saddle-shaped depression known as the sella turcica, a name derived from Latin meaning “Turkish saddle.” This indentation holds significant importance within the cranial cavity for understanding human anatomy and various medical conditions.
The Sphenoid Bone
The sella turcica is an integral part of the sphenoid bone, an unpaired bone situated centrally in the skull. This bone is uniquely shaped, often likened to a butterfly. Its central location positions it towards the front of the skull, just in front of the occipital bone. The sphenoid bone connects with nearly every other bone in the skull, earning it the designation of a “keystone” bone of the cranium. This extensive articulation provides rigidity and stability to the skull, forming a significant portion of the cranial base and contributing to the orbital floor.
Anatomy and Function of the Sella Turcica
Within the sphenoid bone, the sella turcica forms a distinct, saddle-like depression. The most inferior portion of this depression is called the hypophyseal fossa. This concavity serves to house and protect the pituitary gland. The pituitary gland, a pea-sized endocrine gland, is often referred to as the “master gland” due to its role in regulating numerous bodily functions through hormone production. The sella turcica provides a bony seat, safeguarding this delicate gland from external forces and impacts.
Clinical Relevance
The sella turcica serves as an important anatomical landmark in the medical field. Its location and the structures it houses make it a frequent focus in medical imaging, such as MRI and CT scans. Radiologists and clinicians evaluate the sella turcica for abnormalities in size, shape, or contour, which can indicate conditions related to the pituitary gland or surrounding brain structures. For instance, an enlarged sella turcica can sometimes be associated with pituitary tumors, while a shrunken gland might be observed in conditions like empty sella syndrome.
The sella turcica also serves as a key surgical landmark, particularly for accessing the pituitary gland. The transsphenoidal approach, a common surgical technique, involves navigating through the nasal passages and sphenoid sinus to reach the sella turcica. This method allows surgeons to access and treat pituitary conditions, such as tumor removal, by going through the nose, avoiding a traditional craniotomy.