Introduction
Conventional esophagogastroduodenoscopy (EGD) is limited by the requirement for sedation
and its associated recovery time, endoscopy suite resources, and anesthesia monitoring.
These limitations likely decrease the effectiveness of current screening strategies
for esophageal precancerous lesions [1]. Unsedated small-caliber transnasal endoscopy (TNE) has been investigated as a less
expensive, efficient, office-based alternative to EGD for screening for gastroesophageal
reflux complications.
TNE is a well tolerated procedure with an excellent safety profile [2]
[3]
[4]
[5]. The acceptability rate of TNE was 85.2 % in a recent meta-analysis including 1597
patients; furthermore, 63 – 80 % of individuals preferred TNE to EGD for future procedures
[6]
[7]
[8]. Technical success rates of TNE and EGD were comparable (particularly when TNE scope
diameter was < 5.9 mm) [8]. TNE has also been shown to be sensitive for detecting Barrett’s Esophagus (BE)
in subjects with known or highly suspected BE [9]
[10]
[11]. Yet, the perceived TNE drawbacks including relatively inferior image quality and
smaller biopsy samples have limited the integration of TNE into clinical practice
for screening. Comparisons of EGD and TNE imaging quality are lacking in the community-based
setting. The impact of procedural location on endoscopic imaging quality has also
not been reported.
We recently conducted a randomized community trial showing that TNE screening (in
the hospital endoscopy suite or mobile research van) had similar participation rates
and screening yield compared to EGD [7]. In the current study, we aimed to compare the endoscopic examination quality of
TNE (performed in two different settings) with EGD from this recent trial and assessed
TNE imaging quality based on procedural setting.
Methods
In our recent randomized trial reported by Sami et al., 209 community subjects, 50
years or older in age without history of prior endoscopy, stratified by age, sex,
and gastroesophageal reflux disease (GERD) symptoms, were recruited and randomly assigned
to receive endoscopic screening by one of the three methods: TNE performed in a mobile
research van unit (mTNE), TNE in a hospital endoscopy suite (hTNE), or EGD [7]. Each endoscopy was conducted by an endoscopist with TNE and EGD expertise and who
had performed over 1000 upper gastrointestinal endoscopic examinations (PGI and LMW).
EGD procedures were performed using a conventional high definition endoscope (GIF-180,
Olympus America, Center Valley, PA, United States) under conscious sedation. hTNE
and mTNE were performed using the EndoSheath® transnasal esophagoscope (TNE-5000, Vision Sciences, Orangeburg, NY, United States)
following administration of nasal and oral topical anesthesia. All procedures were
video recorded.
Two blinded reviewers evaluated the de-identified videos of TNE and EGD procedures.
The reviewers planned to evaluate 120 videos of the 205 procedures in the trial. Videos
were randomly selected proportionally (2 EGD, 1 hTNE, 1 mTNE) from the collection
to mitigate the introduction of selection bias. Procedure recording was started after
oral or nasal intubation to further blind the reviewers from distinguishing TNE from
EGD procedure videos. Five videos were not scored because the video was incomplete
due to technical difficulties or the recording began before/during oral or nasal intubation.
The reviewers were trained how to use the scoring tool and shown standardized scored
videos as scoring models. Scorers were instructed to watch the video in entirety,
pause the video each time before scoring, and rewind as many times as needed to ensure
accurate scoring.
The reviewers assessed endoscopic quality utilizing a validated scoring tool, which
was developed to evaluate the endoscopic skills of a diverse group of proceduralists
(including gastroenterologists, non-gastrointestinal physicians, and physician extenders)
through video review [12]. The following proficiencies were assessed: achievement of proper technique with
esophageal intubation (including degree of visualization of pharyngeal and upper airway
structures), achievement of proper technique with esophageal tubular passage (including
maneuvering with direct vision, visualization of anatomic landmarks, proper insufflation
and suctioning), percent area of gastroesophageal junction (GEJ) visualized on insertion
and on withdrawal, and overall examination quality [12]. Additional details are provided in the example scoring instrument (Appendix 1). Assessment scores were recorded using a Likert scale of 1 to 5 (5 being the best)
based on the criteria achieved in each of the five aforementioned proficiencies.
Demographic characteristics were reported using the mean and standard deviation (SD)
for continuous data and the frequency and proportion for categorical data. Quality
characteristics were compared using the Student’s t test or chi-squared test as appropriate.
Inter-rater agreement of endoscopy quality was assessed with Cohen’s kappa coefficient
analysis. Standard statistical software (SAS® version 9.3, SAS Institute, Cary, NC,
United States) was used for analysis.
Results
The reviewers scored 115 videos (58 EGD, 28 hTNE, and 29 mTNE). Baseline characteristics
for the reviewed videos compared to the study cohort are included in [Table 1]. There was no statistically significant difference in demographics, procedure time,
or proportion of diagnosed esophagitis or BE in the subset of videos reviewed compared
to the videos not reviewed (data not shown). The study cohort was 46 % male with a
mean (SD) age of 65 (9) years. Esophagitis was discovered in 32 % of those screened
(62 total, 29 Los Angeles (LA) grade A, 29 grade B, 4 grade C), while 7.8 % of screened
subjects had confirmed BE. Mean (SD) length of the endoscopic exam was 9.3 (1.6) minutes
for EGD, 8.0 (2.7) minutes for hTNE, and 8.5 (2.5) minutes for mTNE (P = 0.51). Representative images taken during EGD and TNE examinations are shown in
[Fig. 1].
Table 1
Baseline characteristics of the reviewed procedures compared to the total study procedures.
|
Total (n = 205)
|
Reviewed (n = 115)
|
Not reviewed (n = 90)
|
P value
|
|
Age, mean (SD), years
|
65.5 (9.2)
|
66.5 (9.2)
|
64.3 (9.0)
|
0.08
|
|
Male sex, n (%)
|
94 (46 %)
|
48 (42 %)
|
46 (51 %)
|
0.18
|
|
Duration of endoscopic exam, mean (SD), min
EGD
hTNE
mTNE
|
9.3 (1.6)
8.0 (2.7)
8.5 (2.5)
|
9.3 (1.7)
8.5 (3.0)
8.8 (2.4)
|
9.1 (1.0)
7.7 (2.6)
8.3 (2.7)
|
0.68
0.34
0.59
|
|
Presence of esophagitis or metaplasia, n (%)
|
68 (33 %)
|
38 (33 %)
|
30 (33 %)
|
0.96
|
P < 0.05 considered significant.
Fig. 1 These video still-images are prototypical images of the three endoscopic methods.
a shows laryngeal structures visualized. b demonstrates the tubular esophagus. c visualizes the gastroesophageal junction.
[Table 2] presents the quality assessment scores of the three groups. In comparisons of the
EGD and combined TNE (mTNE and hTNE) groups, EGD received higher scores in tubular
esophageal passage (P < 0.05) with a reduced number of red outs and an increased percentage of maneuvering
under direct vision. The TNE group scored higher in esophageal intubation compared
to EGD (P < 0.05) due to more frequent visualization of key laryngeal anatomic structures and
direct visualization of esophageal intubation posterior to the larynx. There were
no differences in GEJ visualization scores with insertion (P = 0.58) or withdrawal (P = 0.47) between the groups as > 95 % of the GEJ was visualized in nearly all cases.
The overall quality scores for TNE and EGD were excellent without statistically significant
differences (P = 0.30). There was no significant difference in any quality assessment score between
mTNE and hTNE groups, which were different only in procedural location. Inter-rater
agreement of endoscopy quality was excellent (kappa = 0.88).
Table 2
Comparison between TNE and EGD quality assessment scores.
|
Quality assessment score
|
Group EGD (n = 58)
|
Group mTNE (n = 29)
|
Group hTNE (n = 28)
|
P value for comparison of EGD vs. all TNE
|
P value for comparison of mTNE vs. hTNE
|
|
Esophageal intubation score, mean (SD)
|
1.5 (1.6)
|
3.8 (1.1)
|
3.3 (1.9)
|
< 0.05[1]
|
0.21
|
|
Tubular esophagus passage score, mean (SD)
|
3.6 (0.7)
|
2.3 (0.7)
|
2.5 (1.1)
|
< 0.05[1]
|
0.34
|
|
GEJ visualization score during insertion, mean (SD)
|
4.9 (0.2)
|
4.9 (0.3)
|
4.9 (0.2)
|
0.58
|
0.59
|
|
GEJ visualization score during withdrawal, mean (SD)
|
4.9 (0.3)
|
4.9 (0.3)
|
4.8 (0.4)
|
0.47
|
0.53
|
|
Overall esophageal examination score, mean (SD)
|
4.1 (0.2)
|
4.1 (0.3)
|
4.0 (0.1)
|
0.42
|
0.22
|
GEJ, gastroesophageal junction.
1
P < 0.05 considered significant.
Discussion
In this brief report, we found that the quality of esophageal assessment with TNE
(conducted in a gastrointestinal endoscopy suite (hTNE) or in a mobile research van
(mTNE)) was comparable to EGD in terms of overall quality and GEJ visualization. TNE
received higher esophageal intubation scores, likely due to passage through the nasal
cavity into the superior oropharynx, which provided superior visualization of the
laryngeal and oropharyngeal structures. EGD scored higher in tubular esophagus passage
metrics likely due to greater insufflation capabilities compared to the ultrathin
TNE endoscope. TNE quality was not affected by procedure setting as there was no difference
in quality scores between the mTNE and hTNE groups. These results indicate that TNE
using the EndoSheath technology is a feasible efficient option for endoscopic assessment
of reflux complications in a population-based setting.
The scoring tool employed in this study to assess endoscopic quality was validated
in a large multicenter study performed in the UK that included over 4000 subjects
with a diverse group of endoscopists [12]. That study had some limitations. The scoring tool did not include assessments to
evaluate the endoscopist’s diagnostic yield or esophageal lesion identification. In
our previously published study, Sami et al. reported no difference in suspected or
confirmed BE rates between the three arms (EGD, mTNE, or hTNE) of the study [7]. These results are akin to multiple studies showing that TNE is comparable to EGD
at detecting BE [9]
[10]
[11]. The scoring tool also did not assess the endoscopist’s level of comfort or perceived
difficulty of the procedure. These additional personal viewpoints could be incorporated
into future investigations of TNE used in primary care settings with endoscopists
less experienced with TNE. It was also difficult to completely blind reviewers from
the potentially different appearances of TNE and EGD videos. Nevertheless, by applying
a clear scoring system, it was hoped that videos were scored on their merit rather
than as a comparison.
As we have previously reported, there was no difference in the rate of successful
intubation, complete evaluation, or BE screening yield between the three arms (EGD,
mTNE, or hTNE) of this prospective population-based study [7]. Comparing TNE and EGD examinations, the absolute difference in the mean procedure
length was minimal in this study, likely due to the research protocol driven acquisition
of GEJ and esophageal biopsies in all three arms. However, recovery time (extubation
to discharge) was substantially longer by approximately 50 minutes for subjects who
received sedated EGD compared to TNE [7]. This decreased recovery time associated with TNE is beneficial for the patient
as well as the endoscopist. By including a disposable sheath, TNE also avoids the
need for conventional endoscope sterilization between procedures. Given that TNE examination
quality did not differ by procedure setting, TNE could likely be employed effectively
in an office-based setting, community center or even a mobile research unit as investigated
in this study for assessment of complications from gastroesophageal reflux. Furthermore,
a majority of primary care providers may be more willing to refer patients for screening
with TNE if it was readily available (62 %) and to perform TNE in their office if
trained (52 %) [13]. These time-saving, mobile features associated with TNE are ideal for increasing
case volume and accessibility which would be necessary in community-based BE screening
programs.
Current limitations for TNE include the lack of readily available TNE training opportunities
and current endoscopists with TNE experience. However, recent studies suggest that
these shortages are not insurmountable. Alashkar et al. recently reported that physician
assistants and nurse practitioners can be trained to conduct BE screening with TNE
and gain proficiency in 50 procedures [14]. Reasonable, plausible TNE training strategies using available providers and resources
need to be further delineated.
In conclusion, the overall quality of esophageal assessment and GEJ visualization
was comparable for TNE performed using the EndoSheath technology and EGD in a community
cohort. TNE quality was not affected by procedure location and thus could be used
effectively in mobile or office-based settings. These results indicate that TNE is
a feasible option for endoscopic assessment of reflux complications, and can be used
in a community setting.
Appendix 1 – UPPER ENDOSCOPY EVALUATION SHEET
Appendix 1 – UPPER ENDOSCOPY EVALUATION SHEET
Video ID: □ Scorer: □ Date:□
Time, you began scoring: □□ hr □□ min □□ sec
Section A – Dexterity and Safety
This section is to evaluate dexterity and safety of performance of OGD. This includes
instrument entry, passage, and manipulation through the mouth, throat, and oesophagus.
Please check various items under each item before you score. Pause the video each
time before scoring and rewind as many times as needed to ensure accurate scoring.
1. Oesophageal intubation
□ Passage under direct vision all the time
□ Following centre of tongue
□ Visualizing epiglottis
□ Visualize the cricoarytenoid folds and vocal cords
□ Insertion posterior to the larynx between the pyriform sinuses
2. Passage through oesophagus
□ Insertion under direct vision all the time
□ No mucosal red or white outs
□ Adequate air insufflation
□ No mucosal wall collisions
□ Suctioning any secretions
3. Examination of OG junction (Z-line or squamocolumnar junction in particular)
On insertion On withdrawal
□ > 95 % visibility □ □
□ 66 – 95 % visibility □ □
□ 36 – 65 % visibility □ □
□ 5 – 35 % visibility □ □
□ < 5 % visibility □ □
4. Overall Score of Oesophageal Exam
□ Complete examination and no concerns over technique or content
□ Probably complete examination with minor concern over technique or content
□ Incomplete examination with moderate concern over technique or content
□ Incomplete examination with major concern over technique or content
□ Incomplete examination and totally unacceptable technique or content
Time, when you finish scoring: □□ hr □□ min □□ sec
