Doppler tissue perfusion measurement is a sensitive and specific tool for a differentiation between malignant and inflammatory pancreatic tumors

Characterization of oral biomarkers during early healing at augmented dental implant sites

AIM

The aim of this study is to assess early wound healing expression of local angiogenic biomarkers following connective tissue graft (CTG) at dental implant sites.

METHODS

Twenty-eight subjects with single dental implants exhibiting a soft tissue dehiscence were included and randomly treated with CTG, either with coronally advanced flap (CAF) or with tunnel technique (TUN). Peri-implant crevicular fluid (PICF) was collected at the midfacial and midlingual aspect of the implant sites at baseline and at 3, 7, 14, 30, and 90 days after the surgical intervention. The expression of angiogenin (ANG), fibroblast growth factor-2 (FGF-2), platelet-derived growth factor (PDGF), tissue inhibitor of metalloproteinases-2 (TIMP-2), and vascular endothelial growth factor (VEGF) was investigated over a period of 3 months. Patient-reported outcomes, clinical measurements, and ultrasonography scans at multiple time points were also evaluated.

RESULTS

The longitudinal regression revealed a significant difference in the expression of VEGF and TIMP-2 between CAF- and TUN-treated sites over 3 months (p = .033 and p = .004, respectively), whereas no significant differences were observed for ANG, FGF-2 and PDGF between the two groups. At 7 days, a direct correlation was observed between ANG levels and ultrasonographic color velocity in the CAF group (p < .001) and between ANG levels and ultrasonographic color power in the TUN group (p = .028). VEGF levels and ultrasonographic mean perfused area of the CTG were significantly correlated at the 7-day time point (p < .001 for both CAF and TUN). The expression of VEGF at 7 days was directly associated with mucosal thickness gain at 1 year (p < .001 for both groups). Early TIMP-2 expression showed an inverse correlation with time to recovery (p = .002). TIMP-2 levels at 3 months exhibited inverse correlations with mean dehiscence coverage (p = .004) and the rate of complete dehiscence coverage (p = .012).

CONCLUSION

PICF biomarkers can be used to monitor early wound healing events following soft tissue grafting at implant sites. VEGF and TIMP-2 showed correlations with the 1-year clinical and volumetric outcomes, as well as with post-operative patient-reported outcomes and Doppler Ultrasonographic tissue perfusion-related parameters.

Doppler ultrasonographic evaluation of tissue revascularization following connective tissue graft at implant sites

AIM

To assess the Doppler ultrasonographic tissue perfusion at dental implant sites augmented with connective tissue graft (CTG) using coronally advanced flap (CAF) or tunnel technique (TUN).

MATERIALS AND METHODS

Twenty-eight patients presenting with isolated healthy peri-implant soft-tissue dehiscence (PSTD) were included in this randomized clinical trial. PSTDs were treated with either CAF + CTG or TUN + CTG. Ultrasound scans were taken at baseline, 1 week, 1 month, 6 months and 12 months. Tissue perfusion at the mid-facial, mesial and distal aspects of the implant sites was assessed by colour Doppler velocity (CDV) and power Doppler imaging (PDI). Early vascularization of the graft and the flap at 1 week and at 1 month were evaluated via dynamic tissue perfusion measurements (DTPMs), including flow intensity (FI), mean perfusion relief intensity (pRI) and mean perfused area (pA).

RESULTS

Regression analysis did not reveal significant differences in terms of mid-facial CDV and PDI changes between CAF and TUN over 12 months (p > .05), while significant differences between the two groups were observed at the interproximal areas (p < .001 for both CDV and PDI changes). Higher early DTPMs were observed at the TUN-treated sites in terms of mean FI of the graft (p = .027) and mean FI (p = .024) and pRI of the flap (p = .031) compared with CAF-treated sites at 1 week. Assessment of the FI direction showed that CTG perfusion at 1 week and at 1 month mainly occurred from the flap towards the implant/bone. Early tissue perfusion outcomes were found to be associated with the 12-month mean PSTD coverage and mucosal thickness gain.

CONCLUSIONS

Doppler ultrasonography shows tissue perfusion changes occurring at implant sites augmented with CTG. The main differences in tissue perfusion between CAF and TUN were observed at the interproximal sites, with early perfusion associated with clinical and volumetric outcomes at 12 months.

Dynamic Doppler Ultrasound Assessment of Tissue Perfusion Is a Better Tool than a Single Vessel Doppler Examination in Differentiating Malignant and Inflammatory Pancreatic Lesions

Dynamic tissue perfusion measurement (DTPM) and single vessel flow measurement (SVFM) were assessed in differentiating inflammatory and malignant lesions of the pancreas. Sixty-nine patients (age 62.0 ± 14.7; 33 Female and 36 Men; 40 with malignant and 29 with inflammatory lesions) in whom during the endoscopic ultrasound (EUS) of focal pancreatic lesions it was possible to adequately evaluate the flow in the color Doppler, and then perform a biopsy, were qualified for the study. The assessed DTPM parameters flow velocity (TFV), perfusion intensity (TPI), and resistive index (TRI) as well as the following SVFM parameters: flow velocity (FV), volume flow (VolF), and resistive index (RI) differed significantly between the malignant and inflammatory lesions (p < 0.005). TFV and TPI have slightly better discriminatory properties than the corresponding FV and VolF parameters (p < 0.10). Considering the Doppler parameters usually evaluated in a given method, the TPI = 0.009 cm/s (sensitivity 79%, specificity 92%, AUC 0.899, p < 0.001) was significantly better (p = 0.014) in differentiating between inflammatory and malignant pancreatic lesions in comparison to FV = 2.526 cm/s (sensitivity 79%, specificity 70%, AUC 0.731, p < 0.001). Tissue perfusion has better discriminatory properties in the differentiation of solid pancreatic lesions than the Doppler blood flow examination in the single vessel within the tumor.