IntroductionCHAPTER 1

In scans upto 15 weeks a full bladder is required, unless transvaginal. It is preferable to examine upto 12 weeks by a transvaginal scan.

Between 15 and 22 weeks holding urine for one hour is sufficient.

After 22 weeks no preparation is required. A full bladder for assessment of the cervix and lower segment assessment can be asked for when required.

The patient need not be fasting unless and until an upper abdomen scan is also asked for.

The patient is almost always scanned supine with plenty of jelly on the abdomen. In certain cases scanning in the lateral position (if patient is uncomfortable lying supine or fetus moves when lying in a lateral position) or with the patient standing (for functional assessment of cervix) is required.

Whenever, a transvaginal scan is asked for the bladder must be emptied immediately before the examination. It should be performed with the same respect for privacy and gentleness, as is with the placement of a speculum. Scanning is performed with the patient supine and with her thighs abducted and knees flexed.4

Elevation of the buttock may be necessary. The probe should be covered with a condom or sheath containing a small amount of gel. Additional gel should be placed on the outside of sheathed tip. The probe is inserted by a gentle push posteriorly towards the rectum while the patient relaxes. Four types of probe movements are required:

For a transabdominal scan, a 3.5 to 5.0 MHz transducer and for a transvaginal scan, a 5.0 to 8.0 MHz transducer is used.

Basic controls of every machine are more or less the same. The placement of knobs is different for all machines. Check for the manual of your machine or somebody from the company can always come and explain you.

The routine knobology is: