|Uterus TA probe positioning for longitudinal scan.||Uterus sagittal US image.|
|Uterus TA probe positioning for transverse scan.||Trans abdominal view of the uterus: transverse. Both ovaries are visible (not always the case).|
|Transvaginal Technique Anteverted uterus.||
Normal TV image anteverted sagittal.
The overall uterine length is evaluated in the long axis from the fundus to the cervix (external os). The depth (AP diameter) is measured from the anterior to the posterior wall and perpendicular to the length.
|Retroverted transvaginal technique hl.||Retroverted uterus transvaginal scan.|
Evaluation of contour changes, variations in echogenicity, masses and cysts. Any pathology must be measured in 2 planes. Fibroids should be labelled if they are submucosal,intramural,subserosal or pedunculated and there position within the uterus (Rt,Lt,Midline,Fundal,Body or cervical)
|The probe is turned slowly anticlockwise to visualise the uterus at 90degrees to the sagittal view.The Maximum Width is measured in this transverse (coronal) plane.
Assess the endometrial status and measure the thickness: <10mm pre menopausal; <4mm post menopause or <6mm if post menopausal on HRT
|Sagittal US image of the uterus obtained during the proliferative phase of the menstrual cycle demonstrates the endometrium with a multilayered appearance||Normal premenopausal endometrium. Sagittal US image of the uterus obtained during the secretory phase of the menstrual cycle shows a thickened, echogenic endometrium|
The copper IUD
The copper IUD is a small plastic device with copper wire wrapped around it and a fine nylon string attached to the end. When the IUD is in place, the string comes out through the cervix into the top of the vagina.
The hormonal (Mirena) IUD
The hormonal (Mirena) IUD is a small plastic ‘T-shaped’ device that contains progestogen. This is a synthetic version of the natural hormone progesterone. The device has a coating (membrane) that controls the release of the progestogen into the uterus. Like the copper IUD, it has a fine nylon string attached to the end to make checking and removing it easier. The hormonal IUD is available in Australia under the brand name Mirena.
Ultrasound is routinely used to check the position .
|IUCD is seen here approximately 1.5cm from the end of the uterine fundus.
||The string is seen correctly positioned in the cervical canal.
The coronal plane can improve visualisation of the uterine shape and the endometrium. Congenital abnormalities can be diagnosed more confidently. Fibroids and polyps are much easier to visualise. Cornual ectopics can also be better appreciated.
It is displayed by gaining a good 2D image and rendering it into 3D images.
|This is a rendered 3D image using a Transvaginal approach.
|Coronal 3D image of a Mirena IUD shows the expected location of the shaft and crossbars simultaneously in the body and fundus of the uterus. The endometrium is also seen well without the normal shadowing of the mirena always seen in the sagittal plane.
||The string can be difficult to identify on the 3D in the cervix but a 2D sagittal scan should easily show its plecement.
ROLE OF ULTRASOUND
EQUIPMENT SELECTION AND TECHNIQUE
The patient empties their bladder before the transvaginal scan is started.
This is a generalised overview to identify the cervix, uterus and ovaries.
Scan sagitally in the midline immediately above the pubis. Heel the probe to get the bladder over the fundus of the uterus. In this plane you should be able to assess the uterus, vagina and cervix. Zoom the image to assess and measure the endometrial thickness. Rotate into transverse and angle slightly cranially to be perpendicular to the uterus. Whilst in transverse and slightly right of midline, angle left laterally to identify the left ovary using the full bladder as an acoustic window. Examine the ovary in two planes. Now repeat this for the right ovary.
INSERTING THE TV PROBE
|For Uterine Pathology|
|For Ovarian Pathology|
POUCH OF DOUGLAS (POD) & ADNEXAE
|Embryology of the Uterus
Bladder and Bowel should also be examined.
A pelvic series should include the following minimum images;
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