Pelvic CT scan shows us the anatomy of the pelvis. The pelvis includes the reproductive organs like the uterus and ovaries in women and the prostate in men. We see the bladder, parts of the bowel, the blood vessels, lymph nodes and bones.
How is a pelvic CT done?
Pelvic CT scans can be done with or without contrast given through the vein. Some pelvic CT scans are also done with contrast that you drink. Pelvic CT scans can also be done with rectal contrast in some circumstances.
Pelvic CT scans can be done with a focus on the bones or the soft tissues. Pelvic CT scans often go a bit beyond the pelvis including the lower abdomen and part of the thighs. Often pelvic CT scans are done in combination with CT scans of the abdomen.
Why is a pelvic CT done?
Pelvic CT scans alone are often ordered for broken pelvic bones when there is trauma. These types of pelvic CTs will be done with a technique geared towards showing us bone detail. They are done in different projections called axial, coronal and sagittal. This is basically a way to show the bones in different ways. There are many pelvic bones which can get broken. CT is the best at showing us these fractures.
Pelvic CT scans are more often done for the soft tissues or everything inside. These are done for pelvic symptoms like pain. I see these ordered when there is a rectal abnormality suspected like an abscess or pus collection. These will often be drained surgically to prevent complications.
Pelvic CTs are done when hernias are suspected based on a doctors physician exam or because a patient has a history of one. Hernias are protrusions of normal pelvic structures like bowel or fat through a defect. Sometimes hernias can get entrapped and squeeze the blood supply. This can cause pain and may need urgent surgery to fix.
Pelvic CTs ordered for pain
Pelvic CTs are sometimes ordered for general pain. Many abnormalities can cause pelvic pain. In women, abnormalities of the reproductive organs like cysts of the ovaries or fibroids of the uterus can cause pain. We can see enlarged ovaries from torsion or twisting of the ovary. We can also see a thickened infected bladder in some cases.
Both men and women can have abnormalities of bowel. These can be blockages or abnormal twisting (volvulus). We can see bleeds from various causes settle in the pelvis. We can sometimes catch the appendix and diagnose appendicitis. The prostate can be abnormal in men and show enlargement or infection with an abscess.
Pelvic CTs can also show enlarged lymph nodes. This can occur from infection, systemic conditions or cancers. We can see abnormalities of the blood vessels like aneurysms, tears (dissections), blockages, and clots. We can see spread of cancer from other locations in the body.
Pelvic CTs therefore provide a lot of information and can show many abnormalities. Some tests are better for structures of the pelvis. An ultrasound of the uterus and ovaries can show us more detail then a CT. The prostate is better evaluated with MRI. The best way to look inside the bladder is with cystoscopy. Therefore, a normal CT does not end the workup of a problem that is suspected in the pelvis.