Crohn’s disease is a form of inflammatory bowel disease characterized by chronic inflammation that can affect any part of the gastrointestinal tract, from the mouth to the anus. Endoscopy is the established method for visualizing and assessing the extent and severity of disease activity within the gastrointestinal lining. This procedure uses a flexible tube equipped with a light and a camera to provide a detailed, magnified view of the digestive tract.
Endoscopy’s Purpose in Crohn’s Care
Endoscopy serves several distinct medical functions for individuals managing Crohn’s disease, extending far beyond the initial identification of the condition. For a new diagnosis, the procedure confirms the presence of inflammation and allows for the objective collection of tissue samples, called biopsies, which are necessary to establish the diagnosis. The visual information helps differentiate Crohn’s disease from other conditions, such as ulcerative colitis, by noting the pattern and location of inflammation, which often appears in discontinuous “skip lesions” in Crohn’s.
Endoscopy is used for monitoring how effectively current treatments are working to manage inflammation. By periodically examining the mucosal lining, doctors can assess the objective response to medications, a concept known as mucosal healing. Endoscopic procedures are also used after surgery to check for the recurrence of inflammation, particularly near the sites where sections of the bowel were reconnected.
Specialized Endoscopic Techniques
Because Crohn’s disease can affect the entire digestive tract, the specific type of endoscopic technique employed depends on the segment of the bowel that needs examination. The most common procedure is a colonoscopy, which allows visualization of the large intestine and often extends to the terminal ileum, the final section of the small bowel that is a frequent site of Crohn’s inflammation. If symptoms suggest involvement higher up in the system, an upper endoscopy, or esophagogastroduodenoscopy (EGD), is used to inspect the esophagus, stomach, and the first part of the small intestine, the duodenum.
For the middle small intestine, which is often inaccessible to standard scopes, capsule endoscopy is used. This involves swallowing a pill-sized device that contains a tiny camera, which captures thousands of images as it naturally passes through the entire small bowel. This method is purely diagnostic, as it does not allow for biopsies or therapeutic interventions.
When intervention or deeper visualization of the small bowel is required, balloon-assisted enteroscopy (BAE) is utilized. This technique employs a scope with an attached balloon or overtube system, which allows the physician to advance the scope much deeper into the small intestine than a standard scope permits. BAE enables the doctor to take tissue samples, stop bleeding, or perform therapeutic procedures like balloon dilation of strictures.
Patient Preparation and Procedure Day
Preparing for an endoscopy, particularly a colonoscopy, is focused on ensuring the bowel is completely clean so the physician can clearly see the mucosal lining. This preparation typically begins a few days before the procedure by switching to a low-fiber diet, avoiding items like seeds, nuts, and raw vegetables. For the 24 hours immediately before the procedure, the diet is restricted to clear liquids, such as broth, clear juices, and gelatin.
The most demanding part of the preparation is drinking a prescribed solution that causes the complete evacuation of the bowel contents. Physicians often recommend a split-dose regimen, where half the solution is consumed the evening before and the remainder several hours prior to the procedure. Proper completion of this step is important for the accuracy of the examination and to minimize the risk of complications.
On the day of the procedure, an intravenous (IV) line is placed to administer sedation. The sedation level can range from conscious sedation, where the patient is drowsy but responsive, to general anesthesia. The procedure itself usually takes less than an hour, and the patient is monitored in a recovery area afterward until the effects of the sedative wear off. Due to the medications given, patients must arrange for a responsible adult to drive them home and should plan to rest for the remainder of the day.
Understanding Endoscopic Findings
When the physician views the lining of the gastrointestinal tract, they are actively looking for specific visual markers of Crohn’s disease activity. Common findings include erosions and ulcers, which can range from small, shallow aphthous ulcers to large, deep, linear ulcers. Another sign is “cobblestoning,” which occurs when deep linear ulcers and surrounding swelling create a nodular, irregular appearance in the mucosa.
Tissue samples are routinely collected during the procedure, even from areas that appear visually normal, because the biopsy provides microscopic confirmation of inflammation and helps rule out other complications. These samples are analyzed by a pathologist to assess the severity of inflammation and to screen for precancerous changes, particularly in patients who have had Crohn’s disease for many years.
To objectively measure the severity and track healing over time, physicians use standardized tools like the Simple Endoscopic Score for Crohn’s Disease (SES-CD). This scoring system quantifies variables across five segments of the colon and ileum:
- The size of ulcers.
- The extent of ulcerated surface.
- The extent of affected surface.
- The presence of narrowing or strictures.
Mucosal healing, often defined as a low SES-CD score, is the treatment goal because it correlates with a lower risk of long-term complications and disease progression.