Aims: Frequency-domain optical coherence tomography (FD-OCT) provides a rapid tomographic scan of a coronary vessel, with an accurate reconstruction of its lumen profile. An FD-OCT-based metric that corresponds more closely with physiological significance of lesions may enable more precise guidance of interventional procedures. The aim of this feasibility study was to evaluate a new method for quantifying coronary lesion severity that estimates hyperaemic flow resistance of branched vessel segments imaged by FD-OCT. Methods and results: An analytical flow model was developed that relates fractional flow reserve (FFR) to the vascular resistance ratio (VRR), a measure of blood flow resistance derived ...
In one aspect, the invention relates to system comprising: a processor configured to receive a first optical coherence tomography (OCT) data set obtained during a pullback of a data collection probe along a first length of a first blood vessel; determine a minimum lumen area disposed along the first length using the first OCT data set; and determine a first FFR value along the first length based on the minimum lumen area. In one embodiment, the first FFR value is an estimated FFR. In another aspect, the invention relates to a method that includes measuring, using OCT, the area of ...
In part, the invention relates to methods, apparatus, and systems suitable for determining a fractional flow reserve (FFR) and variations of modifications thereof One embodiment relates to a method and apparatus for obtaining a corrected FFR in a vessel having a stenosis. In one aspect, the invention relates to an apparatus for measuring corrected FFR of a vessel having a stenosis. In one embodiment, the apparatus includes a probe comprising an optical coherence tomography assembly and a pressure assembly; and a processor in communication with the optical coherence tomography assembly and the pressure assembly. In one embodiment, the pressure assembly ...
Two main nonsurgical endoscopic approaches for ablating dysplastic and early cancer lesions in the esophagus have gained popularity, namely, radiofrequency ablation (RFA) and cryospray ablation (CSA). We report a uniquely suited endoscopic and near-microscopic imaging modality, three-dimensional (3D) optical coherence tomography (OCT), to assess and compare the esophagus immediately after RFA and CSA. The maximum depths of architectural changes were measured and compared between the two treatment groups. RFA was observed to induce 230~260
Background: Radiofrequency ablation (RFA) is an endoscopic technique used to eradicate Barrett's esophagus (BE). However, such ablation can commonly lead to neosquamous epithelium overlying residual BE glands not visible by conventional endoscopy and may evade detection on random biopsy samples.Objective: To demonstrate the capability of endoscopic 3-dimensional optical coherence tomography (3D-OCT) for the identification and characterization of buried glands before and after RFA therapy.Design: Cross-sectional study.Setting: Single teaching hospital.Patients: Twenty-six male and 1 female white patients with BE undergoing RFA treatment.Interventions: 3D-OCT was performed at the gastroesophageal junction in 18 patients before attaining complete ...
