Most abdominal surgeries done are for cancers. Infrequently they are performed for conditions such as diverticular disease, ulcerative colitis, Crohn's disease, chronic constipation or rectal prolapse.
There are 2 ways that abdominal surgery is performed: (1) Open Approach and (2) Laparoscopic Approach.
The cut is made through the abdomen. This may be vertically downwards or horizontally across your abdomen, depending on the nature of the disease.
The diseased part of the colon is then approached. The blood vessels that supply this part of the colon is cut and tied off. If this is an operation for cancer, the lymph nodes are also carefully removed.
Removing part of the colon is called colectomy. Numerous names of operation such as right hemicolectomy, left hemicolectomy and sigmoid colectomy all refer to removing a different part of the colon.
This differs from the open approach described above in that the abdominal cavity is visualized through a fibre-optic camera (called the laparoscope) inserted through a small 1cm hole at the umbilical region instead of a long cut. Several specialized instruments are then inserted though 3 – 4 tiny holes about 0.5cm to 1cm in size (hence the name “key-hole” surgery) to remove the diseased part of the colon. Only a small cut is made at the end of the surgery to retrieve the specimen. In some situations, following insertion of the laparoscope, the surgeon may find that the diseased portion of the colon is unsuitable for removal via the laparoscopic approach and convert the surgery to an open approach.
Most operations do not require a stoma.