Dr Louise Moore, diagnostic radiologist at Bay Radiology, Tauranga.

WHY DO I NEED TO CHECK ON MY BOWEL HEALTH?

Colon can­cer (also known as col­orec­tal or bow­el can­cer) is a lead­ing cause of can­cer deaths in New Zealand. Bow­el can­cer most com­mon­ly starts with­in polyps. Polyps are growths aris­ing from the sur­face of the colon or rec­tum. They become very com­mon as peo­ple get old­er. Although polyps are non-can­cer­ous (benign), occa­sion­al­ly a change can take place inside a polyp and bow­el can­cer can start. Colon can­cer is often silent for many years. If caught ear­ly, colon can­cer may be cured.

WHAT IS A CT COLONOGRAPHY?

CT colonog­ra­phy (CTC), is a CT scan to look at the colon, or large bow­el. A CT scan is a spe­cialised x-ray test, dur­ing which the patient lies on a mov­ing table/bed as it pass­es through a cir­cu­lar x-ray machine.

WHY WOULD MY DOCTOR REFER ME TO HAVE THIS PROCEDURE?

The main pur­pose of a CTC is to look for can­cer or polyps in the large bow­el. If a can­cer or sig­nif­i­cant sized polyp is found, you will need to have anoth­er test, such as a colonoscopy for biop­sy or to remove the polyp. CTC is also excel­lent for diag­nos­ing diver­ti­c­uli­tis, where pouch­es devel­op in the wall of the colon, or as an inves­ti­ga­tion if you have symp­toms sug­ges­tive of bow­el prob­lems. Anoth­er rea­son to have a CTC is if you have had a dif­fi­cult or incom­plete con­ven­tion­al colonoscopy, when the whole bow­el may not have been com­plete­ly or con­fi­dent­ly assessed.

WHAT DOES THE CT COLONOGRAPHY EXAMINATION INVOLVE?

In order to study the large bow­el, dietary prepa­ra­tion and pre­scribed lax­a­tives are required to cleanse the bow­el. Dur­ing the exam­i­na­tion, the large bow­el is filled with car­bon diox­ide through a small tube in the rec­tum and then a CTC scan is per­formed. A bow­el relax­ant is usu­al­ly given to help this process. The car­bon diox­ide is read­i­ly absorbed by the body, which reduces the dis­com­fort expe­ri­enced. No seda­tion is required and it is gen­er­al­ly pos­si­ble to return to work short­ly after the pro­ce­dure. After the CTC scan, a radi­ol­o­gist with exper­tise in inter­pret­ing CTC will analy­se the images and give a writ­ten report to your refer­ring doc­tor.

ARE THERE ALTERNATIVE TESTS TO CT COLONOGRAPHY?

A colonoscopy is a stan­dard way of exam­in­ing the bow­el, in which a tube with a cam­era on the end (colono­scope) is passed into the large bow­el through the rec­tum. It is more inva­sive than CTC and usu­al­ly requires seda­tion. Opti­cal colonoscopy is the pre­ferred screen­ing test for peo­ple at high­er risk of colon can­cer. Dis­cuss with your doc­tor which test may be right for you.

CT colonog­ra­phy is avail­able through Bay Radi­ol­o­gy, fol­low­ing a refer­ral from your gen­er­al prac­ti­tion­er or spe­cial­ist.

 

FIND A BAY RADIOLOGY LOCATION NEAR YOU

Tau­ran­ga: 71 Ten­th Ave

Tau­ran­ga Hos­pi­tal: 829 Cameron Rd

Mt Maun­ganui: 8 Grenada St

Oropi: Grace Hos­pi­tal, 281 Cheyne Rd

Katikati: 4 Clive St Te Puke: 27 Queen St

Whakatāne: 17–19 Pyne St

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