subsellar

Subsellar is an anatomical term describing a location beneath the sella turcica, the saddle-shaped depression in the sphenoid bone that houses the pituitary gland. The word combines sub-, meaning under, with sellar, relating to the sella. In clinical and radiologic contexts, subsellar refers to structures, tissues, or pathologies located inferior to the sella turcica and in its immediate base region.

Anatomical context and boundaries

The subsellar region lies just below the sella turcica. Its superior boundary is formed by the floor of the sella or the covering diaphragma sellae, and its inferior boundary is near the roof of the sphenoid sinus. Lateral relationships include the cavernous sinuses and parasellar elements, while nearby midline structures can include portions of the pituitary stalk and infundibulum as they pass toward the hypothalamus. The optic apparatus is located above the sella, so lesions in the subsellar area may affect inferior aspects of the pituitary stalk or adjacent skull base tissues.

Clinical significance

Pathology in the subsellar region may accompany lesions that extend from the sellar compartment or originate adjacent to it. This can include pituitary or infundibular abnormalities, as well as infrasellar extensions of tumors such as pituitary adenomas, craniopharyngiomas, or meningiomas. Symptoms, when present, may involve endocrine dysfunction, headache, or, depending on extent, visual disturbances from nearby structures. Imaging assessment typically uses MRI for soft tissue detail and CT for bone boundaries to delineate subsellar involvement.

Imaging and reporting

In radiology reports, subsellar extension is described to characterize a lesion’s position relative to the sella turcica. Understanding subsellar anatomy helps guide surgical planning and management of skull base pathologies.

Etymology

Subsellar derives from sub- (under) and sellar (pertaining to the sella turcica).