Examination of the small bowel has been considered a challenge for several anatomical (i.e. distance from external orifices, length) and physiological (i.e. active peristalsis) reasons. Conventional techniques of endoscopy are limited by length while radiologic examinations, such as barium studies, are insensitive for evaluating small bowel pathology. An ingestible miniature camera device capable of obtaining images of the whole small intestine was developed due to a need for the exploration of this "final frontier". The purpose of this article is to review and share our institution's results using small bowel capsule endoscopy, with special reference to the existing literature.

1. INTRODUCTION

   Examination of the small bowel (SB) has been considered a challenge for several anatomical (i.e. distance from external orifices, length) and physiological (i.e. active peristalsis) reasons. Conventional techniques of endoscopy are limited by length while radiologic examinations, such as barium studies, are insensitive for the evaluation of pathology in the SB. An ingestible miniature camera device capable of obtaining images of the whole small intestine was developed due to a need for the exploration of this "final frontier". Video capsule endoscopy (CE) is a breakthrough in medical history for noninvasive imaging of the entire small intestine. It was first introduced in 2000, and since then more than 700 studies have been published, which is indicative of its ease and the widespread acceptance of this new diagnostic tool. A wide range of uses for CE has been reported in the literature, but the majority of the studies have aimed to evaluate the cause of obscure gastrointestinal bleeding (OGIB).

2. RATIONALE The purpose of this article is to review and share our institution's experience using small bowel CE, with special reference to the existing literature. Most published reports on capsule endoscopy are limited to small group of patients.

3. STUDY OBJECTIVES 3A. Primary Objective- To study the indications and diagnostic yield of capsule endoscopy.

3B. Secondary Objective- To study the gastric emptying time, small bowel transit time and findings visualized with capsule endoscopy.

4. STUDY POPULATION This observational retrospective study will be conducted in AIG Hospitals, Hyderabad. All patients who underwent capsule endoscopy till 30 June, 2021 will be enrolled in the study.

5. DESIGN AND DURATION OF THE STUDY- It will be a retrospective observational study.

6. METHODOLOGY

6a. SUBJECT RECRUITMENT - All patients who underwent capsule endoscopy in our hospital till 30 June, 2021 will be enrolled in the study.

6b. RANDOMIZATION AND BLINDING- N/A

6c. STUDY METHODS- This observational study will be conducted after obtaining ethical clearance from institutional human ethical committee. All patients who underwent capsule endoscopy till date will be enrolled in the study.

6d. STUDY PROCEDURE- The data will be entered in Microsoft excel sheet and analysed ' 6e. METHODS OF ASSESSMENT- The following variables will be noted. A. Age of the patient B. Indications of the procedure C. Pre-Existing illness D. Gastric Emptying time E. Small Bowel transit time F. Capsule Retention G. Findings visualized on capsule endoscopy study

6e. STOPPING OR DISCONTINUATION CRITERIA- N/A

7. SAMPLE SIZE CALCULATION- The sample size will include all patients who underwent capsule endosocopy till 30th June 2021 in AIG hospitals Hyderabad.

8. STATISTICAL ANALYSIS- Data will be expressed as median and percentile values (5th, 25th, 75th and 95th percentiles). The upper limit of normal will be defined as the 95th percentile of expected values. P≤0.05 will be considered statistically significant.

9. ETHICAL JUSTIFICATION OF THE STUDY Small Bowel Capsule endoscopy is a safe and effective procedure for diagnosis of small bowel disorders. It is especially helpful in finding the cause for obscure gastro-intestinal bleed. There is lack of large studies on diagnostic yield and other visualized findings. This study aims to share our institution's results using small bowel CE, with special reference to the existing literature.

Inclusion Criteria:

• All patients who underwent capsule endoscopy in AIG Hospitals Hyderbad till 30 June, 2021 will be enrolled in the study.

Exclusion Criteria:

• Patients in whom capsule was unable to reach caecum.

The study includes patients who underwent capsule endoscopy from Jan 2013 till 30 June, 2021.

It's yet undecided.