Teaching basic gynecological and obstetric ultrasonography remains a challenge; it typically consists of limited personal instruction by an expert while a patient, having agreed to a ‘training exam’, is being scanned.
This website presents a simple tool that may help to learn and teach gynecological ultrasound, based on a proposed standardized approach (Tutschek et al. UOG 2012). It uses interactive webpages according to the HTML5 standard that is supported on most modern browsers including Smartphones. These are image files containing stacks of parallel sections in a standard orientation optimized to show relevant anaomitcal structure or landmarks.
Transabdominal or transvaginal insonation?
The combination of both approaches provides most information. For beginners the transabdominal (TA) insonation enables an easier understanding of the anatomical relationships. However, an echogenic abdominal wall and intervening bowel can limit image quality. The transvaginal (TV) approach provides better resolution due to the higher frequency of the TV transducers and the closer proximity to the pelvic organs. However, an extended uterus, large fibroid or ovaries lying far cranial to the uterus can often not be seen better with TV insonation.
Beginning to scan and getting the orientation: the transabdominal approach
The abdominal transducer is positioned in the midline cranial to the pubic bone. The landmarks to be included in the starting image should be the maximum sagittal diameter of the bladder and usually a median section of the uterus.
Then, the transducer is placed paramedian plane, retaining the longitudinal orientation, on the right and then left side and just medial to the pelvic bone. The landmark to see is a longitudinal section of the external iliac vessels.
Orientation in transvaginal scanning
When performing an transvaginal scan, the image on the ultrasound system’s screen can be oriented to show the transducer tip on the bottom or the top of the screen (down or up). The position of the bladder can be to the left or the right of the screen. Whichever way is used does not really matter as long as the operator does so consistently and can find the orientation in the images easily. FOr this website, trasvaginally acquired images are displayed with the transducer on the bottom of the screen and ventral (towards the bladder) on the left of the screen (green box in the following image).
Performing a transvaginal scan
The TV transducer has limited options of spatial positioning (tilting, rotating, partial insertion) and requires more skill to obtain diagnostic sections. Lowering the handle of the TV transducer directs the viewing angle to the front lifting the handle to the back. Tilting the TV transducer to the sides directs the view towards the pelvic walls and the ovarian fossa; additional rotation to the side often permits viewing of the uterus, the tube and the ipsilateral ovary.
Different orientations for the display of TV images are being used: With the probe on the top or on the bottom of the image, and with the bladder on the left or the right of the image. This orientation does not affect image quality or diagnostic capabilities, but a standardized use is recommended. In this website / tutorial for transvaginal scanning the transducer is shown on the bottom of the image and the ventral part to the left, as shown on the green frame:
When inserting the probe, it should be carefully introduced in the axis of the vagina, taking care not to exert pressure to the anterior vaginal wall. Partially insertion into the introitus only allows examination the urethra , the undistended vagina and the rectum dorsally.
When the probe is fully inserted its tip is usually placed in the anterior fornix and in contact with the anterior lip of the cervix.
Assessing the endometrium
Assessing the ovaries
Intramural fibroids
hemorrhagic ovarian cyst B-mode only with color Doppler