Probe-based confocal laser endomicroscopy quantitative morphometric markers associated with portal hypertension in duodenal mucosa.

ABSTRACT

BACKGROUND & AIMS: Early detection of portal hypertension (PH) may help to prevent the morbidity of late-stage cirrhosis by stratifying disease severity and enabling disease-modifying interventions in potentially reversible conditions like non-alcoholic fatty liver disease and alcoholic hepatitis. This study seeks to correlate morphometric features by confocal endomicroscopy with established surrogate clinical markers of PH. METHODS: Patients with and without PH scheduled for upper endoscopy at VA Boston participated in this IRB-approved study. Real-time probe-based confocal endomicroscopy (pCLE) was performed in the duodenum. Vascular and epithelial morphometry was performed off-line, in a blinded manner, using image-processing software. RESULTS: Morphometric analysis of pCLE images from 16 patients with PH and 15 control patients was performed. Statistically significant differences were observed among control and PH patients for average vessel diameter (AVD 11.7 µm vs. 17.1 µm), average vessel branching (AVB 0.11 vs. 0.31 bifurcations per image frame), and average columnar cell height (ACCH 40.0 µm vs. 52.0 µm). Spearman correlations comparing AVD, AVB and ACCH to portal gastropathy scores (0.86, 0.44 and 0.70) and to grade of oesophageal varices (0.88, 0.41 and 0.66) were statistically significant. Similarly, Pearson correlations of AVD and ACCH to spleen size (0.72 and 0.57), platelet count (-0.69 and -0.40) and the platelet count/spleen size ratio (-0.69 and -0.41) were also found to be statistically significant. CONCLUSIONS: Duodenal pCLE reveals microvascular dilatation and altered epithelial cell volume/morphology in PH. These morphometric pCLE markers correlate with surrogate markers of PH. Additional studies will define the correlation between microscopic vascular patterns, epithelial cell volume and the hepatic venous pressure gradient.