Ultrasound Assessment of Deep Infiltrating Endometriosis
Endometriosis is a condition in which tissue identical to that which lines the uterus (endometrial cavity) is found elsewhere in the pelvis. Common locations for endometriosis include the surfaces of pelvic organs, the walls of the pelvis and behind or within the ovaries. The endometriotic tissue responds to the cycle of hormones in the same way that the uterine lining does, growing and bleeding each month. The small amounts of internal bleeding which occur during a period result in inflammation, pain and scarring. Over time collections of blood can build up in or around organs and the organs can become tethered (stick to each other).
Endometriosis can also involve the bladder, vaginal and bowel walls. The scarring that occurs results in infolding of the walls as blood collections develop. This is often referred to as Deep Infiltrating Endometriosis. Women with endometriosis in these locations may experience pain with bowel movements or blood in the stools or urine during menstruation.
Transvaginal ultrasound can be used to help locate Deep Infiltrating Endometriosis and guide the managing doctor in providing advice about the most appropriate forms of treatment and possible complications. However, as the bowel is filled with the forming stool and gas, both of which hamper ultrasound views, some preparation is ideal.
How do I Prepare for Ultrasound Assessment for Deep Infiltrating Endometriosis?
The lower bowel needs to be empty. This is achieved with laxatives and enemas which can be purchased over-the-counter at your local pharmacy.
The day before your examination, aim to avoid high fibre foods (eg. fruits, vegetables, high fibre cereals and wholemeal/wholegrain breads). Drink extra fluids throughout the afternoon. Consider having a soup meal that evening. You can eat as usual the next morning.
Before going to bed, take 2 tablets of a laxative (Dulcolax is a suitable example). Drink an extra glass or 2 of water. Be prepared for the possibility of a visit to the toilet in the night or early morning.
If the laxative tablets have not been effective in the morning (and particularly if you suffer constipation) use a self-administered enema (Micro-lax is a good example). After insertion into the rectum it should be held for 5 minutes if possible. It is usually effective soon after this.
The result from the laxatives (with or without the enema) usually leaves the bowel suitably empty for a few hours. Thus it is ok to use them well before a scheduled appointment, to avoid the risk of needing a toilet urgently when you are travelling to the appointment.
Will I Have Pain with the Ultrasound Examination?
Many women with severe endometriosis do experience more discomfort or pain with transvaginal scanning. For this reason, you may like to consider taking a couple of pain-relief tablets before you come. Options are an anti-inflammatory, such as Nurofen or Naprogesic, or paracetamol (with or without codeine) such as Panadol or Panadeine.
When Should I Schedule the Appointment?
The best time is in the 2 weeks leading up to your period. This is because fluid released due to ovulation is often helpful in outlining the structures in your pelvis. If you are taking 'the pill' you will not be ovulating, and the timing doesn't matter. Many women with endometriosis have more pain during menstruation, and for this reason we recommend against scheduling the appointment for a time when you expect to have your period.