484 GASTROINTESTINAL ENDOSCOPY VOLUME 55, NO. 4, 2002
Accuracy of a narrow-diameter battery-powered
endoscope in sedated and unsedated patients
Andrew Catanzaro, MD, Ashley Faulx, MD, Patrick R. Pfau, MD, Gregory Cooper, MD, Gerard Isenberg, MD,
Richard C. K. Wong, MBBS, Michael V. Sivak, Jr., MD, Amitabh Chak, MD
Cleveland, Ohio
Background: Esophagoscopy with a portable battery-powered endoscope could provide a safe,
inexpensive, and minimally invasive way to screen for Barrett’s esophagus or esophageal varices.
The use of such an instrument in an unsedated fashion has not been previously evaluated.
Methods: Patients referred for an EGD were recruited to undergo an additional examination with
the battery-powered endoscope before EGD. In phase 1, (n = 42) patients received conscious seda-
tion before the battery-powered endoscopic examination. In phase 2, (n = 56) patients were not
sedated and were given the option of a peroral (n = 43) or transnasal (n = 13) endoscopy.
Examiners were blinded to patient history and procedure indications. Esophageal findings, ease
of intubation, optical quality, and patient comfort for the battery-powered endoscope and standard
EGD were recorded by the endoscopist.
Results: Ninety-eight patients (60 men, 38 women, mean age 53 years) were recruited. The sensi-
tivity for detecting Barrett’s esophagus, esophageal tumors, and esophageal varices was 54.5%,
66.7%, and 80%, respectively. Ease of intubation and patient comfort as perceived by the endos-
copist were not significantly different between the battery-powered endoscope and EGD. Optical
quality was ranked as less than 4 (on a 5-point scale with 5 = standard EGD and 1 = poor) in 42%
of battery-powered endoscopic examinations. There were no complications.
Conclusion: The accuracy of esophageal examination with a 3.1-mm endoscope is substantially
inferior to standard EGD.Thus, the battery-powered endoscope would not be useful for screening
patients for Barrett’s esophagus or varices unless improvements in optical quality and visualiza-
tion are made. (Gastrointest Endosc 2002;55:484-7.)
The use of a small-caliber endoscope for unsedat-
ed endoscopy has been evaluated in multiple stud-
ies.
1-4
Previous studies have shown that unsedated
endoscopy with these instruments (usually with
diameters of 5-6 mm) is reasonably well tolerated
and has a sensitivity of 90% and a specificity of 97%
for detecting upper GI disease as compared with
standard endoscopes.
3
Advantages of unsedated
endoscopy include avoidance of side effects from
sedative medications, which could potentially
account for as much as half of the morbidity and
mortality of upper GI endoscopy.
5-9
In addition,
patients can return to work directly after the proce-
dure. This results in a marked decrease in cost of the
procedure. However, a substantial number of
patients in the United States still find unsedated
procedures with these instruments unacceptable as
evidenced by a 31% to 43% refusal rate of patients
who were asked to participate in these studies.
10,11
In addition, a small but significant increase in chok-
ing/gagging was noted in two studies of unsedated
thin-caliber endoscopy versus standard sedated
endoscopy.
3,4
A reduction in endoscope diameter to
less than 5 mm could potentially improve the accep-
tance of unsedated endoscopy, if such an instrument
provided diagnostic accuracy comparable with stan-
dard endoscopy.
A 3.1-mm diameter, 60-cm–long battery-powered
instrument designed for esophagoscopy alone has
recently been developed (Olympus America, Inc,
Melville, N.Y.). Because this instrument is portable
and battery powered, it could potentially be used for
a range of indications in the outpatient clinic set-
ting. The aims of this study were to evaluate the
tolerance and diagnostic accuracy of unsedated
esophagoscopy with this portable, battery-powered,
narrow-diameter fiberoptic endoscope, to compare it
with conventional sedated endoscopy, and to explore
possible applications in clinical practice.
PATIENTS AND METHODS
The study was conducted from July to December of 2000.
Examinations were performed by 1 of 3 attending endos-
Received June 15, 2001. For revision August 20, 2001. Accepted
September 26, 2001.
From the Division of Gastroenterology, University Hospitals of
Cleveland, Case Western Reserve University, Cleveland, Ohio.
Presented as a poster at the annual meeting of the American
Society for Gastrointestinal Endoscopy, May 20-23, 2001, Atlanta,
Georgia (Gastrointest Endosc 2001;53:AB82).
Reprint requests: Amitabh Chak, MD, University Hospitals of
Cleveland, 11100 Euclid Ave., Cleveland, OH 44106-1736.
Copyright © 2002 by the American Society for Gastrointestinal
Endoscopy 0016-5107/2002/$35.00 + 0 37/1/122576
doi:10.1067/mge.2002.122576