What Is Diverticulosis?

In diverticulosis, many balloon-like sacs (diverticula) develop in the large intestine, most commonly in the last part of it (sigmoid colon). Most diverticula vary in diameter from 1/10 inch to almost half an inch (about 3 to more than 10 millimeters). For unclear reasons, some diverticula become very large. Giant diverticula, which are rare, are larger than 1½ inches (about 4 centimeters) in diameter.