Other Gastroenterology Services

We offer a wide variety of gastroenterology services. Learn, in greater detail, about each procedure below:

Virtual Colonoscopy

Virtual colonoscopy, also known as CT (computed tomography) colonography is a radiology test that examines the colon using CT x-ray technology. The radiology images are reconstructed to create a ‘virtual’ tour of the colon. Virtual colonoscopy is strictly a diagnostic test and does not afford the ability to obtain biopsies or remove polyps. If polyps or an abnormality are discovered, a colonoscopy will be recommended requiring that the patient repeat the preparation process. It is important to know that virtual colonoscopy is performed without sedation.

Virtual colonoscopy has been found to be less reliable than colonoscopy in detecting polyps. In a study of 600 patients at nine major clinics, the accuracy of virtual colonoscopy varied considerably, depending on the training and methods of the doctors performing the exam. The American College of Gastroenterology recommends that people get a conventional colonoscopy, calling it the gold standard of colon cancer screening.


Sigmoidoscopy is a procedure that enables your physician to examine the lining of the lower one-third of the colon. This part of the colon is known as the “sigmoid colon.” The instrument is known as a sigmoidoscope and it is a flexible tube about the thickness of your little finger. There is a light source and camera on the end of the sigmoidoscope; the image is projected onto a video screen. While the patient is sedated, the sigmoidoscope is inserted into the rectum and advanced through the sigmoid colon. Polyps can be removed and biopsies (tissue samples) can be obtained. The procedure takes about 5-10 minutes. Sigmoidoscopy is basically a shorter version of a colonoscopy. Sigmoidoscopy was formerly the primary test for colon screening, but it has been replaced by colonoscopy because colonoscopy is a more complete and thorough test.

Learn More About Sigmoidoscopy »

Small Bowel Capsule Endoscopy

Capsule endoscopy is a procedure that uses a tiny wireless camera to take pictures of your small intestine. The camera is contained inside a vitamin-sized capsule that you swallow. As the capsule travels through your small intestine, the camera takes a video that is transmitted to a recorder you wear on a belt around your waist. Capsule endoscopy helps your doctor see inside your small intestine — an area that isn’t easily reached with conventional endoscopy.

Capsule endoscopy is used to help diagnose conditions that can affect the small intestine, for example obscure GI bleeding, Crohn’s disease, celiac disease, or tumors.

Learn More About Small Bowel Capsule Endoscopy »

Esophageal Manometry and pH Testing

Esophageal manometry is a test that helps to determine how well your esophagus is functioning. Your esophagus is a muscular tube that connects your throat to your stomach. Esophageal manometry measures the rhythmic muscle contractions (peristalsis) that occur in your esophagus when you swallow. During esophageal manometry, a thin, flexible tube (catheter) that contains sensors is passed through your nose, down your esophagus and into your stomach. Esophageal manometry can be helpful in diagnosing some disorders that affect your esophagus.

Esophageal pH testing is typically done in conjunction with esophageal manometry. Esophageal pH testing is a test that helps to determine the extent and degree of acid exposure within the esophagus. During esophageal pH testing, a small caliber catheter is inserted through your nose and positioned within the esophagus. Typically, the catheter is secured in place and allowed to take measurements over a 24-hour period.

Endoscopic Ultrasound

Endoscopic ultrasound (EUS) is a procedure that allows your physician to examine GI structures in great detail using ultrasound technology. EUS utilizes endoscopes that are equipped with ultrasound probes on the tips of the endoscopes. EUS can evaluate abnormalities in virtually every part of the luminal GI tract (from esophagus through to rectum) as well as the liver, gallbladder, bile ducts, and pancreas. EUS is useful in staging cancers of the pancreas and GI tract and for evaluating gallstones. EUS-guided biopsies and fine-needle aspiration techniques allow minimally invasive sampling of tissue from tumors and lymph nodes not easily accessible by other methods.

Patients in our practice who need EUS services are referred to the Interventional Endoscopy Service at California Pacific Medical Center.


An endoscopic retrograde cholangiopancreatogram (ERCP) is a procedure that combines the use of an endoscope with X-ray pictures to examine the biliary and pancreatic ducts. While the patient is sedated, the ERCP endoscope is inserted through the mouth and advanced until it reaches the point where the bile ducts and pancreatic ducts drain into the duodenum.

ERCP can diagnose and treat certain problems found during the test. If an abnormal growth is seen, a biopsy can be obtained. If a gallstone is present in a bile duct, the doctor can sometimes remove the stone with instruments inserted through the endoscope. A narrowed bile duct can be opened by inserting a small wire-mesh or plastic tube (called a stent) through the narrowed duct.

Patients in our practice who need ERCP services are referred to the Interventional Endoscopy Service at California Pacific Medical Center.

Learn More About ERCP »

Liver Biopsy

A liver biopsy is a procedure to remove a small piece of liver tissue, so it can be examined under a microscope for signs of damage or disease. Your doctor may recommend a liver biopsy if blood tests or an imaging study suggest you might have a liver problem. A liver biopsy also is used to determine the severity of liver disease as in hepatitis C. This information helps guide treatment decisions. A liver biopsy involves inserting a thin needle through your abdomen into the liver and removing a small piece of tissue. A liver biopsy is typically performed using ultrasound guidance.

Patients in our practice who need a liver biopsy are referred to the Interventional Radiology Service at California Pacific Medical Center.

Learn More About Liver Biopsy »

Hepatitis A Vaccine

Hepatitis A vaccine is used to prevent infection caused by the hepatitis A virus (HAV). Hepatitis A is a serious disease of the liver. It is spread most often through infected food or water or may also be spread by close person-to-person contact with infected persons. Although some infected persons do not appear to be sick, they are still able to spread the virus to others.

Hepatitis A is less common in the U.S. and other areas of the world that have higher levels of sanitation. However, it is a significant health problem in parts of the world that do not have such systems. If you are traveling to certain countries or remote areas, hepatitis A vaccine will help protect you from acquiring hepatitis A.

Learn More About Hepatitis A Vaccine »

Hepatitis B Vaccine

Hepatitis B vaccine is used to prevent infection by the hepatitis B virus (HBV). HBV infection is a major cause of serious liver diseases, such as hepatitis, cirrhosis and liver cancer. Immunization against hepatitis B disease is recommended for all newborn babies, infants, children, and adolescents up to 19 years of age. It is also recommended for adults who live in areas that have a high rate of hepatitis B disease or who may be at increased risk of infection from hepatitis B virus.

Learn More About Hepatitis B Vaccine »

Small Intestinal Bacterial Overgrowth Breath Test

Small intestinal bacterial overgrowth (SIBO) refers to a condition in which abnormally large numbers of bacteria are present in the small intestine. Moreover, the types of bacteria in the small intestine more closely resemble the bacteria of the colon than the small intestine. SIBO may lead to symptoms including excessive gas, abdominal bloating, abdominal pain, diarrhea, and sometimes constipation. A breath test is typically required to make the diagnosis of SIBO. The breath test is safe and easy to perform.

Patients in our practice who need a SIBO breath test are referred to the GI Lab at California Pacific Medical Center.

Lactose Breath Test

Lactose intolerance is a condition where one lacks the production of the enzyme, lactase, that is important in digesting the sugar lactose that is contained in milk and dairy products. Lactose intolerance can be hard to diagnose based on symptoms alone. People may think they suffer from lactose intolerance because they have digestive symptoms; however, other conditions such as irritable bowel syndrome can cause similar symptoms. Your physician may first recommend eliminating all milk/dairy products from your diet for a short time to see if the symptoms resolve. A breath test may be necessary to provide more information. The breath test is safe and easy to perform.

Patients in our practice who need a lactose breath test are referred to the GI Lab at California Pacific Medical Center.

Radiology and Laboratory Tests

Our practice does not perform radiology tests or obtain lab tests in the office. Radiology tests (such as x-rays and CT scans) are performed at radiology facilities. Laboratory tests (blood and stools tests) are performed at outside laboratory facilities. Radiology and Laboratory facilities are located near our office and throughout San Francisco and the Bay Area.

Request an Appointment