VIDEO CAPSULE ENDOSCOPY (VCE): Introduction, Evolution, Indications

Video capsule endoscopy (VCE) is a non-invasive imaging technique that enables doctors to visualize the small intestine, and in some cases, the esophagus and colon. This method uses a disposable, pill-sized camera that wirelessly transmits images to an external recorder. The primary reasons for performing VCE include investigating obscure gastrointestinal bleeding (OGIB), suspected or confirmed Crohn's disease (CD), small bowel tumors, celiac disease, and polyposis syndrome.

1. VIDEO CAPSULE ENDOSCOPY Dr. Ajay Kumar Yadav DM resident Gastroenterology, NAMS 2081/10/10

2. CONTENTS Introduction and brief history of VCE Indications and contraindications of VCE Complications of VCE Small bowel VCE VCE for colon, esophageal and gastric conditions Limitations of VCE Unmet needs

3. INTRODUCTION Capsule endoscopy vision began in 1991: Gavriel Iddan , an engineer from the Israeli Defense Ministry + gastroenterologist Eitan Scapa Further collaboration with Paul Swain , an English gastroenterologist, and Shuji Nakamura’s invention of the LED as a light source for optical devices (Nobel Prize in 2014)  further refinement of the capsule endoscope The small bowel is the most extended part of GIT , with an average length of 9 - 15 feet : duodenum (1st 9 inches) f/b jejunum (proximal 2/5th or 40%) and ileum (3/5th or 60%) “ Dark world ” or “ Black box ” of the GIT

4. INTRODUCTION Capsule endoscopes measure 24 to 32 mm in length and 11 to 13 mm in diameter , depending on the manufacturer and product line . All capsule endoscopes have similar components : a disposable plastic-coated capsule + metal oxide semiconductor or high-resolution charge-coupled device ( CCD ) image capture system + a compact lens + LED illumination sources + internal battery source. The mode of data transmission from the capsule is either via ultra-high frequency band radio telemetry ( PillCam [ Medtronic, USA ], EndoCapsule [USA ]) or human body communications ( Mirocam , Intromedic Seoul, Seoul, South Korea ). All available software can identify red pixels to facilitate detection of bleeding lesions

5. Basic components

6. Basic components of Capsule Endoscopy The capsule: one or more camera s + light source + battery + transmitter Sensors: placed on the surface of the abdomen or contained in a belt worn by the patient that is connected to a recorder Software: to process and display images Devices have improved over the years, with wider field of view (140°–360°), more cameras (up to 4 in some models), longer battery life, and variable frame rates: 2 fps when traveling slowly through the stomach and intestines and up to 35 fps when traveling quickly through the distal esophagus . In its journey through the GI tract, the capsule can acquire 50,000 to 60,000 images , which can take from 30 to 90 minutes to review . Real-time viewing is particularly important in detecting active GI bleeding. RAPID Real-Time [Given Imaging/ Medtronic ,USA ], Real Time Viewer [Olympus , USA ], and MiroView Express [ IntroMedic , Seoul, South Korea])

7. Brief history of VCE 2020 The Navicam ( AnX Robotica Inc , Plana, TX) receives FDA approval Gavriel J. Iddan Inventor of Wireless Video Capsule Endoscopy Israeli electro-optical engineer The First VCE was performed in 1999 . Professor Swain swallowed first capsule

8. Development of WCE devices and technologies

9. Indications of VCE

10. First line therapy: Small bowel VCE preferred over DAE / CTE / MRE

11. Contraindications Cognitive impairment

12. Complications

13. Patency Capsule A patency capsule s/b administered in patients with suspected small bowel stenosis or stricture, known small bowel Crohn’s disease, history of small bowel resection , or abdomino -pelvic radiation If an intact patency capsule is excreted within 30 h , it is assumed safe to perform SBCE . The patency capsule contains a radiofrequency identifier chip covered with cellophane-filled barium and lactose, with time released biodegradable plugs at both ends that fully dissolve in 40 to 80 hours if the capsule gets stuck in the GI tract.

14. Complications Rare complications: Battery failure Bowel perforation/obstruction Aspiration of capsule into trachea and bronchial tree (0.1%)

15. Preparation for small bowel VCE On the day before procedure: avoid any tobacco products, stop Iron supplements at least 7 days prior clear liquid diet after lunch bowel prep with 2 L PEG ( ESGE NPO after midnight On the morning of procedure: Defoaming agent ( Simethicon tablets): ↓ intraluminal bubbles and increase visibility ( ESGE ) s/b performed as an outpatient Procedure: higher completion rate ( ESGE ) After ingesting the video capsule: ( ESGE ) nothing by mouth for at least 2 h clear liquid diet allowed 2 h and light snack after 4 h remain ambulatory but should avoid strenuous exercise for 8 h stay away from any strong electromagnetic field like MRI, amateur (HAM ) radio, and airport security during this period.

16. Technical aspects of Small Bowel (SB) Capsule

17. Comparison of Small bowel Capsule Endoscopy 160

18. OGIB and chronic IDA Bleeding from the small bowel is uncommon, accounting for only 5% to 10% of cases of GI bleeding, but it is responsible for up to 80 % of cases of OGIB and can manifest as IDA Most of these lesions are angiodysplasias  small , bleed intermittently In a meta-analysis of 10 studies ( n = 757) comparing SB- VCE and DBE for suspected small-bowel bleeding, the pooled yield for SB- VCE and DBE was 24% for both modalities. In a meta-analysis of 26 studies ( n= 3657) that evaluated SB- VCE in both overt and occult small-bowel bleeding, the pooled rate of rebleeding after negative SB- VCE was 19 % ( 95% CI, .14-.25; P < .0001) and not different for occult versus overt bleeding. Negative SB- VCE may be reassuring and obviate the need for further testing unless rebleeding occurs. The timing of capsule endoscopy is important in detecting the source of OGIB . D etection rate decreases with time : 55% within 1 day of admission vs 18% 5 days after admission

19. VCE guiding DAE ( antegrade vs retrograde) 2006 Gay et al : SBCE transit time-based index was used to decide the DBE insertion route . Retrograde DBE was performed if the capsule transit time from ingestion to lesion detection was > 75 % of the total time from ingestion to caecal visualization. PPV and NPV of this SBCE transit time-based index were 94.7 % and 96.7 % respectively . Li et al. proposed a time-based location index , defined as the time from the pylorus to the lesion as a percentage of the time from the pylorus to the ileocecal valve . In a study of 60 patients who underwent both SBCE and DAE , a cutoff of 60 % was highly accurate in guiding the choice of DAE insertion route.

20. Role of VCE in Celiac Disease When is VCE indicated in Celiac Disease ? P ositive serology or symptoms s/o celiac disease but are unable or unwilling to undergo routine upper endoscopy. N ormal duodenal histology to identify distal small-bowel lesions . Clinical symptoms highly s/o celiac disease despite negative serology (5 % ). To detect serious complications such as ulcerative jejunoileitis , celiac-associated lymphoma , and adenocarcinoma @ 48 % of patients with nonresponsive celiac disease. A meta-analysis of 6 studies involving 166 patients with celiac disease reported a pooled sensitivity of 89% (95% CI, 82-94) and pooled specificity of 95 % (95% CI, 89-98) for celiac disease detection by VCE using a pathology reference standard.

21. VCE in Crohn Disease (CD) About 50% of patients have disease in the colon and terminal ileum , 30% in the small bowel , and 20% in the colon only. The disease is complicated by fistulas , strictures, obstruction, and risk of colonic malignancies Capsule endoscopy can detect CD through 3 findings : mucosal inflammation , disease extension, and strictures . 2 scoring systems : 1 . Lewis score 2. Capsule Endoscopy Crohn’s Disease Activity Index Capsule endoscopy can detect disease in the terminal ileum with a sensitivity approaching 100%, superior to that of CTE and MRE . It can detect jejunal lesions , which have a high risk of relapse VCE is recommended in Pts with known, suspected, or relapsed CD with unexplained symptoms when ileocolonoscopy and imaging studies are negative or when reassessment is beyond the reach of ileocolonoscopy . CD recurrence or progression after small-bowel colectomy

22. Capsule Endoscopy CD Activity Index ( CECDAI ) LEWIS SCORE

23. Small bowel tumors S mall bowel is the site of 2% of all GIT tumors. Benign tumors include leiomyoma, adenoma, lipoma , and hemangioma , while malignant lesions include adenocarcinoma, neuroendocrine tumors, gastrointestinal stromal tumors, and lymphoma. The most common sites in the SB are the ileum , followed by the duodenum and jejunum. VCE is more sensitive for the detection of small polyps (<5 mm ), VCE and MRE have similar detection rates for polyps >10 mm, but MRE appears to be more sensitive for polyps >15 mm . Signs of small-bowel tumors on capsule endoscopy include protruding masses, mucosal disruption , irregular surfaces, discolored areas, and white villi.

24. NSAID -induced Enteropathy Manifestations include petechiae , reddened folds, denuded mucosa, mucosal breaks, angiodysplasias , and strictures. L esions are common with both acute and chronic NSAID use, even with low doses and enteric-coated preparations . Diagnosis : h/o NSAID use in the previous month + endoscopic finding of mucosal damage + improvement of clinical course after stopping drug in the absence of other inflammatory diseases of bowel. Findings on capsule endoscopy include ulcers, erosions, scar formations, luminal stenosis , and diaphragmatic disease of the intestine.

25. Images with VCE

26. How to read Small Bowel VCE ? During VCE , the first gastric image, the first duodenal image, and the caecal image are marked. The reviewer can gather an idea about gastric emptying time and the small bowel transit time from these landmarks. Capsule movement depends on gastric and small bowel motility As the capsule moves fast in the duodenum and proximal jejunum , the risk of missed lesions can be high in these locations. The study may take more than 1 h.

27. Cont.. It is recommended to view the study in the double or quadruple video to improve the visibility of any lesion with max. speed of 20 fps and slowing down when evaluating proximal SB ( ESGE ) Automatic mode: Eliminates similar images, significant reduction of reading time (up to 50%), very low diagnostic miss rate. QuickView mode: number of images of interest can be set as a percentage (e.g., 5%, 15 %, 25 %, and 35%) of all images. Shiotani et al: shorten the capsule reading time but with unacceptably high missed rate S uspected blood indicator ( SBI ): Software developed to detect bleeding in the small bowel. S uboptimal performance: sensitivity of detecting active bleed < 60 %

28. VCE reading

29. Capsule Endoscopy Deployment Device

30. Endoscopic Capsule Placement Indication: Pts with dysphagia, Inability to swallow the capsule, Giant hiatus hernia, G astroparesis , and A bnormal UGI anatomy , part. dual intestinal loop anatomy ( Roux-en-Y gastric bypass, Billroth II GJ , and Whipple surgery ) D elivery system consists of a plastic-covered metal fiber passed through the biopsy channel of a standard endoscope. A clear plastic cap is screwed on the fiber, and then the video capsule is pressed into the cap . The endoscope with the front loaded capsule is then introduced through the mouth into the esophagus and further advanced into the duodenal bulb. The capsule is released from the cap by pulling a handle outside the endoscope that moves the stiff inner wire into the cap

31. Colonoscopic Capsule Endoscopy ( CCE ) Two CCE systems ( PillCam COLON 2 and PillCam Crohn’s , USA ) have been cleared by the FDA for colon visualization . PillCam COLON 2 is designed for visualization of the colon , whereas PillCam Crohn’s is designed for the visualization of both the SB and the colon and specifically for the assessment of CD activity. To ensure adequate colon imaging while maintaining battery life (>10 hours), the CCE -2 captures images at 14 frames per minute after duodenal recognition Preparation of CCE : Low residue diet for 3 days before the procedure and a clear liquid diet the day before the procedure. 4 L PEG solution : 2 L in the evening before the day of the procedure + 2 L on the morning of the procedure. The patient swallows the capsule around 9 AM on the day of the procedure. A real-time viewer is used: when the capsule reaches the SB, the data recorder vibrates and buzzes and gives instructions on the LCD.

32. CCE A 1 st booster dose of SUPREP (6 oz added to 10 oz of water) given  2 nd booster dose of SUPREP (3 oz added to 5 oz water ) given if capsule not excreted within 3 h of ingestion of 1 st booster dose  If capsule remains in the colon 2 h after ingestion of 2 nd booster dose  10 mg of bisacodyl suppository given. 2 nd -generation pillCam COLON capsule 2 (aka CCE-2) Two cameras , each with viewing angle of 172  total 360 views 11.6 × 31.5 mm in size, battery life-saving adaptive function Images of 4 fps when virtually static and 35 fps when in motion

33. Indications of CCE

34. Capsule Endoscopy of the Esophagus and Stomach PillCam ESO : developed by Given Imaging; USFDA approved in 2004 Shape, size , and weight are similar to PillCam SB2 . PillCam ESO (3 rd -generation ) can take pictures of 35 fps and has a wider angle of view of 174 Diseases like esophagitis, Barrett’s esophagus, esophageal cancer, and esophageal varices can be detected by ECE . In one study, the sensitivity and specificity of recognizing Barrett’s esophagus were 60% and 100 %, respectively. The diagnostic pooled sensitivity and specificity of detecting esophageal varices were 83% and 85%, respectively. The diagnostic accuracy of grading medium to large varices was 92 %.

35. PillCam UGI (Medtronic) Similar to PillCam SB3 with battery life of 90 minutes, 1 to 35 fps, and 2 cameras at each end . Only VCE system currently marketed for gastric and esophageal lesions. CapsoCam Plus ( CapsoVision , Calif , USA) Only capsule system that does not include a sensing system 4 cameras to provide 360° views , a battery life of 15 hours, and an embedded recorder that eliminates the need for external receiver equipment. The patient retrieves the capsule from the stool with a magnetic wand supplied in a special kit and brings or mails it back to the clinic to be uploaded and interpreted . Can be used to evaluate the esophagus , stomach, and small bowel.

36. Procedure protocol for ECE Fasting for at least 2 hours T he patient drinks 100 mL of water in a standing position. Then he or she swallows the capsule in the supine position . The patient can sip 10 mL of water at this time. The recording is done in the supine position for 2 min, at a 30 ° inclined position for 2 min, and at a 60° inclined position for 1 min. Then recording is done in a standing position for 15 min.

37. Commercially available VCE Systems

38. Cont..

39. REPORTING P atient name, demographic and contact details, referrer details P rocedure indications , brief history of previous investigations, and relevant medical details. P rocedure-related data: gastric transit time, small-bowel transit time , and overall recording time B owel preparation used, if any and quality of bowel preparation C ompletion/extent of examination Clinical findings: should include (when applicable): estimated lesion size and estimated location objective reporting of any visualized inflammatory changes by means of the Lewis score or CECDAI in CD A dvice .

40. Limitations of VCE

41. Cost effectiveness

42. Unmet needs

43. References Capsule endoscopy in gastrointestinal disease : Evaluation, diagnosis, and treatment . CLEVELAND CLINIC JOURNAL OF MEDICINE 2022 Video Capsule Endoscopy in Gastroenterology Review article Gastroenterol Res. 2022 Small-bowel capsule endoscopy and device-assisted enteroscopy for diagnosis and treatment of small-bowel disorders: ESGE Technical Review 2018 Video capsule endoscopy: ASGE TECHNOLOGY STATUS EVALUATION REPORT 2021