Recent advances in diagnostic upper endoscopy

Table 1 Summary of of key recommendations for improving quality in diagnostic endoscopy

Pre endoscopic preparation

Premedication with simethicone or simethicone and N-acetylcysteine improves visualisation in the stomach and oesophagus

Pronase, a proteolytic agent, increases gastric visibility scores

Allowing clear liquids up to 2 h of endoscopy improves patient anxiety and patient comfort

Use of antispasmodic agents to enhance detection of high risk superficial neoplasms is recommended

Sedation

Patients should be counselled adequately regarding sedation options. Reported satisfaction is higher after endoscopy with sedation

Propofol sedation decreases sedation time and improves the detection of early stage pharyngeal and upper gastrointestinal cancers

Propofol use is associated with better inspection during oesophageogastroduodenoscopy (OGD) and hence offers better quality examination compared to midazolam

In patients undergoing sedation with midazolam, routine fentanyl use reduces additional midazolam doses and shortens procedural times and reduces patient retching

In low risk patients and procedures, the use of a target controlled infusion of propofol and alfentanil administered by a nurse anesthetist has been shown to be safe and improves anesthesia quality

In patients who prefer not to undergo sedation, small caliber OGD performed via transnasal or transoral route may offer better patient tolerability with similar level of diagnostic accuracy

Systemic examination

A mandatory set of systemic images in endoscopy reports may increase quality of reports and reduce variability in interpretation

There is currently no consensus how many pictures should be recorded for an adequate OGD

The use of systemic alphanumeric coded endoscopy approach during endoscopy increases yield of high risk lesions

Endoscopists with high rates of ampulla photo documentation were more likely to detect upper gastrointestinal neoplasms and dysplasia and ampulla photo documentation may be used a quality indicator for thorough gastroscopy

Duration of examination

Endoscopists with average Barrett’s inspection time (BIT) exceeding 1 min per centimeter detected more endoscopically suspicious lesions; A longer BIT correlated with high grade dysplasia and adenocarcinoma detection

Endoscopists with a mean examination time exceeding 7 min for a normal examination were twice as likely to detect high risk lesions and neoplastic lesions compared to their faster counterparts

The effect of longer examination time may be diminished in very experienced endoscopists who are able to readily recognise neoplastic lesions

Various societies and consensus guidelines now recommend at least 7–8 min for an adequate upper endoscopic examination

Routine endoscopy biopsy

No studies have demonstrated that routine biopsy improves detection of high risk lesions during endoscopy

Endoscopists with high biopsy rates were less likely to miss a cancer in patients who undergo interval endoscopy

Image enhanced endoscopy

Detection of oesophageal lesions

Absence of iodine staining on chromoendoscopy, even when negative for dysplasia on initial histology, identifies esophageal lesions with high sensitivity for dysplasia or cancer in later follow ups

Non-magnifying narrow band imaging (NBI) was found to have similar sensitivity with superior accuracy and specificity compared to iodine staining for early squamous cell carcinoma

Endoscopists should be trained in the NBI use. NBI Sensitivity was higher in the hands of more experienced endoscopists

Blue laser imaging (BLI) is comparable to magnifying NBI as well as Lugol iodine chromoendoscopy for detection of early esophageal cancer

Detection of gastric lesions

Newer generation NBI improves pick up rate of focal gastric lesions and intestinal metaplasia compared to high definition white light endoscopy

The magnifying endoscopy simple diagnostic algorithm guideline should be followed to identify early cancers

In the presence of a demarcation line as well as irregular micro surface and/or irregular microvascular pattern, a diagnosis of early gastric cancer can be confidently made

High specificity in excluding gastric neoplasms may reduce the need for unnecessary biopsies if magnifying endoscopy (ME) and NBI is employed

ME-NBI improves visualization of the horizontal margin of early gastric cancer compared to low magnification NBI and chromoendoscopy

BLI- Bright was demonstrated to be superior to white light endoscopy (WLE) in the real-time detection of early gastric cancers

Linked color imaging (LCI) identifies confidently Helicobacter pylori infection, gastric intestinal metaplasia and early gastric cancer

The diagnostic accuracy of magnifying LCI with indigo carmine for small depressed gastric lesions has been shown to be better than both conventional WLE and magnifying BLI

Future developments

Raman spectroscopy differentiates normal gastric tissue from premalignant and malignant tissue and allows real time diagnosis and reduces need for biopsy

Endocytoscopy allows real time diagnosis of Helicobacter pylori positivity, intestinal metaplasia, atrophic gastritis and early gastric cancer. There is good interobserver agreement between endoscopists and pathologists

Neural network based artificial intelligence can now be trained to identify oesophageal squamous cell carcinoma and gastric cancer with high sensitivity and specificity