Right sided diverticular colonic disease is rather uncommon in the Western World. The frequency of this disease is reported in approximately 1-2% of surgical specimens in European and American series, but may reach as high as 43-50% in Asian series [7
]. Controversy persists concerning the origins of caecal diverticula. Right-sided diverticula occur more often in younger patients than do left-sided diverticula [1
]. The majority of colonic diverticula are acquired in nature. These typically are characterized by herniation of mucosa and muscularis mucosa through the colonic wall. They usually are invested with a thin layer of submucosa that is forced out through the weak points in the muscularis propria and the tips ending in the colonic subserosa [1
]. The weak points in the muscle coat represent the sites of entry of the nutrient vessels of the colonic mucosa. Diverticula are generally associated with increased colonic intraluminal pressure. The pathology showed thickened muscularis propria with normal or inflamed colonic mucosa. Caecal diverticula lack the muscular hypertrophy. Recent studies documented that aberrant activity of the matrix metalloproteinases play a role in changing the ratio of type1 to type 2 collagen in cases of diverticulitis, and also human cancer can produce MMPs that are leading to digestion of the extracellular matrix [4
] which may play a significant role in the development of diverticular disease. The solitary caecal diverticula are usually congenital in origin, and thought arising as a sacular projection during the sixth week of embryonic development [10
]. Rare instances of angiodysplasia are reported in association with true caecal and Meckel's diverticula [13
Our findings support this association in cases of true diverticula. This correlation implicates a common aetiological factor. The presence of thick abnormal vessels claimed to trigger local haemodynamic/pressure changes render the background for diverticular disease. One study claimed the morphology of myenteric plexuses, and the ganglion cells differ significantly among segments of the human large intestine. Large intestines with diverticula had significantly more plexuses but significantly fewer ganglion cells than large intestines without diverticula [14
]. The area of the nuclei of ganglion cells was also significantly smaller in large intestines with diverticula. This finding is difficult to investigate due to the presence of severe inflammation in true diverticula of the caecum...
Most patients with right sided diverticula are asymptomatic; however, patients may present with complications of diverticulosis. These include bleeding, diverticulitis, peridiverticular abscess, perforation with fistula formation [15
]. Patients with true caecal diverticla are generally in the younger age group. Those subjects will present with right lower quadrant pain and are often thought to suffer from acute appendicitis. The diagnosis of right sided diverticulitis may subsequently be made in the operating room. It is difficult to differentiate caecal diverticulitis from acute appendicitis. More than 70% of patients with caecal diverticulitis were operated on with a preoperative diagnosis of acute appendicitis [10
]. The correct preoperative diagnosis can be facilitated by ultrasound and computer tomography (CT), which are both highly cost-effective.
CT scanning is a sensitive means by which to detect caecal diverticulitis. The radiographic appearance of the disease; however, mimics that of appendicitis, unless more specific findings such as caecal diverticula or intramural abscess with adjacent inflammation are detected. CT and barium studies are complementary methods of examination that improve our ability to diagnose caecal diverticulitis and its complications [16
MRI of right-side diverticulitis may reveal an out pouching of the right colon with associated circumferential wall thickening of the colon and surrounding inflammatory changes [19
] Some authors suggested ultrasound and CT scan as routine use for abdominal pain of the right lower quadrant, which would probably reduce surgeries and hospital stays [4
]. Recognition of specific imaging findings enables the radiologist to make the correct diagnosis and helps in establishing the appropriate surgical or medical therapy, thus avoiding unnecessary exploration or surgery for some of these surgical conditions, which mimicked acute appendicitis. When the diagnosis is made intraoperatively, the surgical management of the disease is controversial. Conservative management with antibiotics has been suggested for the uncomplicated caecal diverticulitis diagnosed intraoperatively. Excisional treatment for caecal diverticulitis prevents the recurrence of symptoms [20
If technically feasible, aggressive resection with immediate right hemicolectomy should be considered in cases of extensive inflammatory changes, multiple diverticula and caecal phlegmon, or when neoplastic disease can not be excluded. This surgery can be safely performed even in the unprepared colon with few complications [21