Page 79 - Effects of radiotherapy and hyperbaric oxygen therapy on oral microcirculation Renee Helmers

SDFI measurements
In all groups microcirculatory measurements were performed at baseline
(before RT) and every week for 11 consecutive weeks. All measurements were
performed by the same investigator (RH) in the same examination room, kept
at a constant temperature of 22±1oC. After inducing anesthesia and blood
sampling, each animal was placed in a prone position on a flat surface with a
cotton dental roll wedged between the maxillary and mandibular (pre-)molars
to keep the mouth open and providing space for placement of the imaging
probe. Moisturizing of the mouth for good contact between mucosa and probe
tip was performed by irrigation of the oral mucosa with a warm (37oC) sterile physiological saline solution (0.9% NaCl). The imaging probe was covered with
a sterile disposable cap (MicroScan Lens, MicroVision Medical, Amsterdam,
The Netherlands) and placed gently perpendicular on the lingual aspect of
the mandibular mucosa on the diastema (gap) between the incisors and the 4 premolars and aiming for full contact without applying any pressure thereby
avoiding vascular occlusion (pressure) artifacts. Microcirculation recordings were acquired while withdrawing and advancing the lens probe from release and contacting the tissue surface in order to record segments free of pressure artifacts. A 2-min video clip was obtained of 5 adjacent sites on the IR side and the contralateral non-IR side of the inside of the mandible in each subject at each time point.
Microcirculation data analysis
The DVI tapes used for storage of the microcirculation data were converted to digital AVI files with Adobe Premier Pro 1.5 (Adobe Systems Incorporated, San Jose, California, USA) and then analyzed offline. After separating the sequentially recorded sites per time point, 1 clip of each site (4 in total) was selected based on quality judged by good image brightness/contrast, sharpness, clarity and absence of pressure artifacts in conformity with guidelines established by a round table conference based on microcirculation data acquisition and analysis consensus meeting.28 Hereafter, all microcirculation data was analyzed at random by two investigators (RH, NFS) using the Automated Vascular Analysis software package (AVA v3.02, MicroScan Video Microscope System, MicroVisionMedical, Amsterdam, The Netherlands). Analysis of microcirculatory data was performed on vessels with diameters <25 μm for total vessel density (TVD; mm vessel/mm2), perfused vessel density (PVD; mm perfused vessel/ mm2), proportion of perfused vessels (PPV; %)3 and microvascular flow index
Onset of late irradiation effects
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