Topics

Topic

design image
Fundus of uterus

The fundus of the uterus is the broad, curved upper portion of the uterus located above the openings of the uterine (fallopian) tubes. It forms the rounded superior dome of the uterus and plays a key role in pregnancy, serving as the site where uterine measurements such as the fundal height are used clinically to assess fetal growth and uterine enlargement.

Synonyms

  • Uterine fundus

  • Superior portion of uterus

  • Fundal region of uterus

Location

  • Positioned at the superior end of the uterus, above the entry of the uterine tubes

  • Lies posterior to the urinary bladder and anterior to the sigmoid colon and loops of bowel

  • Forms the upper convex border of the uterus that can be palpated abdominally during pregnancy

Relations

  • Anteriorly: Related to the urinary bladder (when empty, bladder lies just inferior to fundus)

  • Posteriorly: In contact with the sigmoid colon and small intestine loops

  • Laterally: Continuous with the uterine tubes at their openings (cornua)

  • Superiorly: Free and rounded, forming the dome of the uterus

Function

  • Provides attachment site for uterine tubes at the cornua

  • Expands during pregnancy to accommodate the growing fetus

  • Serves as an important landmark for fundal height measurement in obstetrics

  • Plays a role in uterine contractions during labor, as the fundus initiates contractile activity

Clinical Significance

  • Fundal height measurement used in obstetric assessments to estimate gestational age and fetal growth

  • Can be the site of fibroids (leiomyomas) or other uterine pathology visible on imaging

  • Uterine rupture during labor often involves the fundus

  • Fundal positioning is important in placental implantation and cesarean section planning

  • Malposition or abnormal shape of the fundus may indicate congenital uterine anomalies (e.g., bicornuate uterus)

MRI Appearance

T1-weighted images:

  • Myometrium of fundus shows low-to-intermediate signal intensity

  • Endometrium at the center appears as a thin intermediate-signal stripe

  • Fibroids within fundus may appear as well-defined low-signal masses

T2-weighted images:

  • Myometrium appears with intermediate signal intensity

  • Endometrium demonstrates bright high signal intensity

  • Pathology such as adenomyosis or fibroids shows altered, often low or heterogeneous signal

STIR (Short Tau Inversion Recovery):

  • Normal fundal myometrium is low-to-intermediate signal

  • Inflammatory changes, edema, or adenomyosis appear bright

T1 Fat-Sat Post-Contrast:

  • Normal myometrium enhances uniformly

  • Fibroids enhance variably (homogeneous, heterogeneous, or rim enhancement depending on degeneration)

  • Endometrium enhances brightly in secretory phase of menstrual cycle

CT Appearance

Non-Contrast CT:

  • Uterus appears as a soft tissue density in the pelvis

  • Fundus identifiable as the upper rounded portion above the bladder

  • Fibroids appear as well-defined masses, sometimes with calcification

Post-Contrast CT:

  • Myometrium enhances moderately and uniformly

  • Endometrium may enhance more brightly depending on phase of cycle

  • Fibroids, tumors, or inflammatory lesions show variable enhancement patterns (heterogeneous, rim, or strong enhancement)

MRI image

fundus of uterus MRI sagittal image anatomy image-img-00000-00000

CT image

fundus of uterus CT sagittal image anatomy image-img-00000-00000