**1. Introduction**

Evaluation of the small bowel in inflammatory bowel disease (IBD) is indicated primarily in patients with newly diagnosed or suspected Crohn's disease (CD) [1]. Small bowel evaluation can also be helpful in IBD- unclassified (IBD-U) who can be re-classified as CD in a significant number of cases. Small bowel evaluation in these settings can be done by imaging (barium meal follow through - BMFT, magnetic resonance enterography/enteroclysis - MRE, computed tomography enterography/ enteroclysis -CTE) or by endoscopy. Small bowel endoscopy refers to endoluminal examination of the small bowel. Endoscopic evaluation of small bowel can be done by small bowel video capsule endoscopy (VCE) (**Figure 1A**), push enteroscopy,

#### **Figure 1.**

*Types of small bowel endoscopy. A. Video capsule endoscopy for small bowel (PillCam, given imaging ltd., Yokñeam Illit, Isareal), B. retained capsule removed at laparotomy, C. single balloon enteroscope (SIF-Q180, Olympus, Tokyo, Japan) with overture and balloon, D. intra-operative enteroscopy being performed at laparotomy.*

device assisted enteroscopy (DAE) (which includes single balloon enteroscopy-SBE, double balloon enteroscopy - DBE, spiral enteroscopy, novel motorised spiral enteroscopy - NMSE and balloon guided endoscopy) (**Figure 1C**) and intra-operative enteroscopy (IOE) (**Figure 1D**) [2].

In about two-thirds of patients with CD, small bowel is involved at diagnosis [3]. Among them, 90% have involvement of terminal ileum. Skip lesions in terminal ileum can lead to false negative results. So for diagnosis of suspected CD, ileo-colonoscopy is the first line investigation [4]. VCE is the preferred initial diagnostic modality in cases with suspected CD and negative ileo-colonoscopy in the absence of obstructive symptoms or known stenosis. However, small bowel evaluation is warranted in all newly diagnosed cases of CD as small bowel is involved in every 2 out of 3 CD patients and the involvement can be discontinuous. In this scenario, cross sectional imaging (CTE/MRE) is preferred over VCE due to its potential to assess transmural and extra-luminal disease. VCE is indicated subsequently if cross sectional imaging is non-contributory. Patients with suspected small bowel involvement on cross sectional imaging or VCE, DAE with small bowel biopsy can provide definitive evidence of CD. Additionally, DAE is recommended for treatment of small bowel strictures amenable for endoscopic therapy, small bowel bleeding and retrieval of foreign bodies/retained capsule. For assessing the response to therapy in small bowel CD, VCE can be considered in primarily nonstricturing CD [2]. Hence, small bowel endoscopy has major implications in the diagnosis and classification, therapeutic decision making and altering treatment outcomes in IBD [5].

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**4. VCE in CD**

*Role of Small Bowel Endoscopy in Diagnosis and Management of Inflammatory Bowel Disease…*

2.Assessment of small bowel involvement in patients with confirmed CD,

5.As a therapeutic tool in small bowel CD (stricture dilatation, retained capsule

6.Evaluation of anaemia and unexplained abdominal symptoms in cases with

8.Investigate anaemia after ileal pouch anal anastomosis (IPAA) in UC [8].

There is no single reference standard for diagnosis of CD. Constellation of clinical history, biochemical and stool biomarkers, endoscopy, cross sectional imaging and histopathology is required for diagnosis of CD [9, 10]. Upto 30% CD patients have isolated small bowel disease. Improvement in endoscopic techniques (VCE, DAE, NMSE) as well as radiographic techniques (CTE/MRE) have revolutionised the diagnosis of small bowel CD [5]. However, options for histopathological confirmation in isolated CD is still limited, which is important in resource limited countries where infections (eg. tuberculosis) still predominate and needs

The original VCE (PillCam, Given imaging Ltd., Yokñeam Illit, Isareal) (**Figure 1A**) was designed for visualisation of small bowel which has undergone many modifications such as higher image resolution and increasing diagnostic yield by faster adjustable frame rate and real time analysis capability [12].

European society of gastrointestinal endoscopy (ESGE) recommends VCE as the first line investigation in suspected small bowel CD in whom ileo-colonoscopy is negative in the absence of obstructive symptoms/known stenosis (**Figure 2**) [2]. This recommendation is based on the high sensitivity and negative predictive value (NPV)(ranging from 96–100%) of VCE in small bowel CD. However, the accuracy and diagnostic yield of VCE in suspected CD could not be determined precisely due

3.Assessment for post-operative recurrence of CD in small bowel after

or foreign body retrieval, haemostasis for small bowel bleed).

7.To rule out CD prior to elective colectomy in refractory UC,

**3. Role of small bowel endoscopy in suspected CD**

to be excluded prior to initiation of therapy [11].

**4.1 VCE in suspected small bowel CD**

The Indications of small bowel endoscopy in IBD are [2, 5]

*DOI: http://dx.doi.org/10.5772/intechopen.96006*

**2. Indications of SB endoscopy in IBD**

1.Suspicion of isolated small bowel CD,

ileo-colonic resection [6],

ulcerative colitis (UC) [7],

4.Small bowel assessment in IBD-U,

*Role of Small Bowel Endoscopy in Diagnosis and Management of Inflammatory Bowel Disease… DOI: http://dx.doi.org/10.5772/intechopen.96006*
