ME is a potent predictor of "silent" ischemic brain lesions among patients with carotid stenosis. An analysis of plaque texture can predict the degree of ME during endarterectomy and is more precise than the standard GSM.

Recent studies have shown that time-resolved optical measurements of the head can estimate changes in the absorption coefficient with depth discrimination. Thus, changes in tissue oxygenation, which are specific to intracranial tissues, can be assessed using this advanced technique, and this method allows us to avoid the influence of changes to extracerebral tissue oxygenation on the measured signals. We report the results of time-resolved optical imaging that was carried out during carotid endarterectomy. This surgery remains the "gold standard" treatment for carotid stenosis, and intraoperative brain oxygenation monitoring may improve the safety of this procedure. A time-resolved optical imager was utilized within the operating theater. This instrument allows for the simultaneous acquisition of 32 distributions of the time-of-flight of photons at two wavelengths on both hemispheres. Analysis of the statistical moments of the measured distributions of the time-of-flight of photons was applied for estimating changes in the absorption coefficient as a function of depth. Time courses of changes in oxy- and deoxyhemoglobin of the extra- and intracerebral compartments during cross-clamping of the carotid arteries were obtained. A decrease in the oxyhemoglobin concentration and an increase in the deoxyhemoglobin concentrations were observed in a large area of the head. Large changes were observed in the hemisphere ipsilateral to the site of clamped carotid arteries. Smaller amplitude changes were noted at the contralateral site. We also found that changes in the hemoglobin signals, as estimated from intracerebral tissue, are very sensitive to clamping of the internal carotid artery, whereas its sensitivity to clamping of the external carotid artery is limited. We concluded that intraoperative multichannel measurements allow for imaging of brain tissue hemodynamics. However, when monitoring the brain during carotid surgery, a single-channel measurement may be sufficient.

SummaryAim: Authors performed a retrospective analysis of causes of recurrent varicose veins following surgery. Methods: They evaluated 89 patients (65 women and 24 men, mean age 49.7 years). All patients previously underwent same surgical procedures (long saphenous vein stripping with/without local multiple avulsions). For the purpose of the study, colour/duplex examinations were applied (Siemens Sonoline Elegra unit). Results: Depending on the type and area of recurrent varicose veins, patients were classified into 4 groups. Group I – 22 patients (persistence of varicose tributaries of LSV in thigh or thigh perforator). Group II – 27 patients (recurrence along the LSV in the calf). Group III – 26 patients (recurrence due to left incompetent short saphenous vein). Group IV – 14 patients (isolated incompetent perforators). Authors conclude, that colour-coded duplex scanning is currently a method of choice in the diagnosis of recurrent varicose veins. High incidence of recurrence due to short saphenous vein incompetence should draw particular attention to this vein in the preoperative assessment of venous system. Recurrence of varicose veins at thigh level is not caused by deep vein insufficiency, but is related to inadequate vein surgery or might be linked to the problem of neovascularisation in this area.