Uterus | Shape

Overall the uterus is pear shaped, and usually bent anteriorly (anteflexed) between the cervix and body.

The cavity is roughly triangular or “T” shaped. The cervix is cylindrical prior to puberty

Shape of the Body of the Uterus

Pear Shape in both the Sagital and Coronal Planes

The uterus is pear shaped as depicted in this overlay sagital (a,b) and coronal (c,d) T 1weighted enhanced MRI study

Sagital Plane

The uterus is pear shaped as depicted in this artistic overlay sagital MRI image

Shaped Like a Pear

The uterus is shaped like a pear

The Avocado – Similarities in Structure and Function

The avocado pear has some interesting implications in the structure and function of the uterus. It is shaped like the eggplant and the pear. It takes between 6 and 12 months to grow an avocado from blossom to ripened fruit. The human gestational period is aboput 9 months uertine structure uterus food in the body

The Uterus in the Sagittal Plane

The sagittal STIR sequence from an MRI study shows the normal appearance of the uterus in a 34 year old female. The pear shaped form is exemplified together with the 3 parts of the uterus. The inner endometrium of intermediate signal, the junctional zone of low signal consisting of compacted smooth muscle with low water content, and the surrounding myometrium of smooth muscle with a higher water content.

Axial Plane Coronal Projection

The axial STIR sequence from an MRI study shows the normal appearance of the uterus in a 34 year old female. Because the uterus is anteverted it lies flat so that in this instance the coronal plane of the uterus is demonstrated. The pear shaped form is exemplified together with the 3 parts of the uterus. The inner endometrium of intermediate signal, the junctional zone of low signal consisting of compacted smooth muscle with low water content, and the surrounding myometrium of smooth muscle with a higher water content. Two high signal cuysts are seen in the right ovary

Large and Lobulated

The CTscan is from a 31year old female, who presents with a pelvic mass.The study reveals a large uterus with multicentric fibroids and mild hydronephrosis The heterogeneous and lobular mass measures 17cms (c-c)by 10cms (A-P) by 12cms (transverse), and is consistent with a

Shape of the Cavity

Ashley Davidoff MD

Introduction

Position and Shape Relates to the Position of the Uterus

40 year old female with normal endometrial cavity and cervical canal and fallopian tubes normal anatomy cervix uterus HSG hysterosalpingogram

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This hysterosalpingogram is from a 26 year old female with normaL endometrial cavity and cervical canal. Note the irregular shape to the cervical canal while the endometrial lining is smooth. Note also the free spillage of contrast from the tubes into the peritoneal cavity (white contrast in d, indicating patent tubes. codefallopian tubes and fimbrae normal anatomy cervix uterus HSG hysterosalpingogram

Filling Defect at the Left Cornu

This 38 year old female presents with a history of infertility. The hysterosalpingogram shows non filling of both Fallopian tubes and a filling defect (green) in the region of the patient’s left cornu that likely is the cause of the obstructed left tube and in part the cause of the infertility. The lesion is most likely a submucosal fibroid.

Heart Shaped

Carcinoma of the Cervix in a Bicornuate Uterus Complicated by Obstruction

74 year old female with bicornuate uterus and dilated endometrial cavities Diagnosis is carcinoma of the cervix with obstruction . The myometrium is overlaid in dark pink, and the endometrial cavity is a heterogeneous orange consisting of both fluid and soft tissue elements.

Fibroid Impingement on the Endometrium

In this sagittal view of a T2 weighted MRI of the uterus of a 42 year old female with multiple fibroids two of which impinge on the endometrial cavity (the larger (light green) from posterior and the smaller (dark green) from anterior resulting in a sigmoid shaped cavity (yellow). In addition incidentally noted Nabothian cysts (orange) are seen within the cervix.

Deformity of the Endometrial Cavity Caused by an Intramural Fibroid

In this sagittal view of the T1 weighted contrast enhanced study of the the uterus of a 46 year old female. The uterus roughly retains its pear shaped structure but the shape of the endometrial cavity is distinctly abnormal as if there is something pushing on it from above. This patient has a diffusely enhancing isointense leiomyoma that impinges on the endometrial cavity.

Large Intramural Fibroid Deforming the Stripe

T2 Weighted Image

In this sagittal view of the T2 weighted MRI of the uterus of a 46 year old female an almost 6cms slightly hyperintense fibroid is seen pushing on the endometrial cavity from above. This patient has a large fibroid aka leiomyoma that impinges on the endometrial cavity.

Filling Defect at the Left Cornu

Arcuate Uterus – T2 Weighted MRI

The T2 weighted MRI in axial projection of a 31 year old female shows the endometrial cavity in coronal view with an arcuate shape. This is a normal variant and has no clinical significance. The follicles in the ovaries are also well demonstrated . CODE uterus endometrial cavity ovary ovaries follicles fx arcuate shape dx normal variant

Bicornuate Uterus T2 Weighted Image

The series of images from a young adult female with Bicornuate uterus with agenesis of the left kidney.

Image a is a coronal T1 weighted contrast enhanced image that shows absence of the left kidney.

Image b is an ultrasound in transverse dimension that shows two endometrial cavities.

Image c is a T2 weighted image that shows 2 separate horns that fuse above a single cervix and overlaid in pink in image d

These findings are consistent with bicornuate uterus with agenesis of the left kidney. Combined congenital anomalies of the uterus and renal system are a well known association.

46527c01 Image Courtesy Ashley DAvidoff MD Copyright

Unicornuate Uterus with Subsequent Pregnancy

34 year old female who presented with infertility had a hysterosalpingogram which showed a unicornuate uterus (a). An MRI confirms the diagnosis using a T2 weighted sequence(b). The patient subsequently fell pregnant and was scanned with a normal 13 week pregnancy(c).

Shape of the Endometrium

Tear Drop

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Normal Pear Shaped Uterys

hx young female presentingwith vaginal bleeding for 2 weeks, hematocrit of 25, left lower quadrant pain, and LLQ mass HCG 7000 fx uterus endometrial stripe ovary fx no intrauterine pregnancy

46749 Davidoff MD

Premenstrual

46317 uterus endometrium shape size normal anatomy USscan Davidoff MD

Arcuate Uterus – T2 Weighted MRI

Abnormal Shapes

Introduction

Large and Lobulated

Filling Defect

Bicornuate Uterus

Courtesy Scott Tsai MD 47671

Unicornuate

uterus congenital infertility fx failure of fusion dx bicornuate uterus patent Fallopian tubes free spillage hysterosalpingogram Courtesy Scott Tsai MD 47673 uterus congenital infertility fx failure of fusion dx bicornuate uterus patent Fallopian tubes free spillage hysterosalpingogram Courtesy Scott Tsai MD 47671