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Paper text:
since the technology introducing video capsule endoscopy was for the first time presented during digestive disease week in may 2000 and the first brief communication was published in nature , video capsule endoscopy has been widely used in clinical practice . to date more than 600,000 capsules have been deployed worldwide .
video capsule endoscopy is a useful tool for evaluating small bowel disease , but appropriate indications and rates of detection , completion , and retention vary .
video capsule endoscopy is based on gastrointestinal motility allowing the swallowed capsule to record the mucosa of the gastrointestinal mucosa as the capsule travels , usually uneventfully , down the gastrointestinal tract . in this case , the patient felt discomfort in the cervical portion shortly after swallowing the capsule .
the equipped real - time viewer continued to show the unchanged image that was different from an ordinary image of the mucosa of the esophagus or stomach .
using upper endoscopy video capsule retention in a zenker diverticulum was clarified and the capsule was safely removed endoscopically .
this report describes the case of a video capsule endoscope lodged within a zenker diverticulum , including the usefulness of the equipped real - time viewer and hood - assisted upper endoscope .
however , a slight iron deficiency anemia was found as follows : red blood cell count 4.47  106 ( normal 4.1 - 5.3  106 ) , hemoglobin 12.1 g / dl ( normal 14.0 - 18.0 g / dl ) , hematocrit 38.7% ( normal 39.0 - 52.0% ) , serum iron 36 g / dl ( normal 80 - 200 g / dl ) , total iron binding capacity 349 g / dl ( normal 271 - 469 g / dl ) , and ferritin 6.4 ng / ml ( normal 27.0 - 211.0 ng / ml ) . all other standard laboratory tests were within normal ranges .
upper endoscopy and colonoscopy did not show any potential cause . immediately after swallowing a capsule endoscope ( olympus , tokyo , japan ) the patient complained of discomfort in the cervical region .
the system was equipped with a real - time viewer that showed an unchanging image different from the expected images of the mucosa of the esophagus or stomach .
the presence of discomfort in the cervical portion and the image of the capsule endoscopy led to the suspicion that the capsule might be lodged within a cervical diverticulum .
upper endoscopy ( gif - xq260 , olympus , tokyo , japan ) under propofol sedation confirmed the retention of the capsule along with food within a zenker diverticulum ( fig .
2 ) . a hood - fitted upper endoscope was used to examine the zenker diverticulum and upper esophagus ( fig .
there are several reports of capsule retention in various types of duodenal , small bowel and large bowel diverticula [ 3 , 4 ] .
not very many reports exist describing retention in a zenker diverticulum , hopefully because the capsule is placed with endoscopic guidance in these patients .
zenker diverticulum was first described by ludlow in 1769 . however , it was friedrich von zenker who recognized zenker diverticulum results from increased intrapharyngeal pressure .
zenker diverticulum is located proximal to the upper esophageal sphincter usually on the posterior hypopharyngeal wall and is thought to result from increased intrapharyngeal pressure .
zenker diverticulum usually occurs between the seventh and eighth decades of life , and rarely before the age of 40 years .
the prevalence of zenker diverticulum among the general population is believed to be between 0.01 and 0.11% .
the incidence varies based on region , but it has been described more frequently in the us , canada and australia than in japan and indonesia . in the uk ,
however , the true incidence of zenker diverticulum is difficult to establish since the number of asymptomatic patients is unknown . in this case ,
retention of the capsule endoscope was the first suggestion of the existence of a heretofore asymptomatic zenker diverticulum , although the patient did have an initial upper endoscopy which should have noted the presence of the diverticulum .
the presence of the real - time viewer proved useful for quickly allowing retention of the capsule within a diverticulum to be considered . whenever a zenker diverticulum is suspected
, the capsule should probably be placed using some nonendoscopic method where it is attached to a holder that could be used , hopefully because the capsule is being placed with endoscopic guidance in these patients [ 5 , 13 ] .
we report the case of a video capsule endoscope lodged within a zenker diverticulum . 
 the system that was equipped with a real - time viewer showed an unchanging image unlike esophageal or gastric mucosa , suggesting that the capsule was elsewhere . 
 the presence of cervical discomfort suggested video capsule retention in a zenker diverticulum . the capsule was removed endoscopically and reinserted using a hood - assisted endoscope and the procedure 
 was completed .