Search results for "Arterial occlusion"

Reentry devices for chronic arterial occlusions.

2019

Implementation of laser speckle contrast analysis as connection kit for mobile phone for assessment of skin blood flow

2014

Laser speckle contrast analysis (LASCA) offers a non-contact, full-field, and real-time mapping of capillary blood flow and can be considered as an alternative method to Laser Doppler perfusion imaging. LASCA technique has been implemented in several commercial instruments. However, these systems are still too expensive and bulky to be widely available. Several optical techniques have found new implementations as connection kits for mobile phones thus offering low cost screening devices. In this work we demonstrate simple implementation of LASCA imaging technique as connection kit for mobile phone for primary low-cost assessment of skin blood flow. Stabilized 650 nm and 532 nm laser diode m…

Detection of flap venous and arterial occlusion using interstitial glucose monitoring in a rodent model.

2010

Background: Free tissue transfer necessitates vigilant postoperative monitoring for vessel occlusion. Unfortunately, most monitoring methods require experienced personnel and are expensive to use. Furthermore, many tests have low sensitivity, low specificity, or significant delay between vessel occlusion and detection. The authors report on a novel method of tissue monitoring that avoids these limitations by tracking interstitial glucose concentration. Methods: Vertical rectus abdominis myocutaneous flaps were elevated in adult rats based on the superior epigastric vessels. Interstitial glucose within the flaps was monitored using a transcutaneous sensor. Interstitial glucose was recorded f…

Hyperspectral evaluation of skin blood oxygen saturation at baseline and during arterial occlusion

2018

Skin capillary blood oxygen saturation is a clinically important diagnostic parameter, which provides valuable information for timely treatment of pathological conditions e.g. sepsis, hypoxemia or decompression illness. Hyperspectral imaging is non-invasive optical techniques with high clinical potential, however its use for skin blood oxygen saturation detection is still challenging, therefore in the present study, a method for in-vivo manipulation of skin oxygen saturation was developed, and reliability of the method evaluated by means of hyperspectral imaging in detection of oxygen saturation. In order to produce alterations of skin capillary blood parameters and oxygen saturation, the p…

Optical multichannel monitoring of skin blood pulsations for cardiovascular assessment

2004

Time resolved detection and analysis of the skin back-scattered optical signals (reflection photoplethysmography or PPG) provide rich information on skin blood volume pulsations and can serve for cardiovascular assessment. The multichannel PPG concept has been developed and clinically verified in this work. Simultaneous data flow from several body locations allows to study the heartbeat pulse wave propagation in real time and to evaluate the vascular resistance. Portable two- and four-channel PPG monitoring devices and special software have been designed for real-time data acquisition and processing. The multi-channel devices were successfully applied for cardiovascular fitness tests and fo…

Composite femoro-tibial bypass as alternative solution in complicated revascolarization: Case report

2021

Introduction Peripheral Arterial Disease (PAD) in diabetic patients is a significant cause of Morbility. Long arterial occlusion in patient previously treated can require unusual and complex solution. Herein we report a case of complicated bypass in diabetic patient with history of bypass for bilateral popliteal aneurysm. Presentation of case A 51-year-old male, smoker, with hypertension and diabetes mellitus was referred to our hospital for rest pain in left limb and peripheral cyanosis. Ultrasound doppler (US) showed an occlusion after common femoral artery with patency of Anterior-tibial artery (ATA) two centimeters after the origin. The unavailability of adequate autologous conduit nece…

Evaluation of nitroglycerin effect on remote photoplethysmogram waveform acquired at green and near infra-red illumination

2017

Assessment of skin microcirculation provides diagnostically valuable information during the early stages of pathologies. The simple, cost-effective and intrusive alternative to existing circulation assessment methods is remote photoplethysmography (rPPG). The objective of the present pilot study was to reveal an effect on sublingual administration of 1 mg nitroglycerin on systemic hemodynamic parameters and rPPG waveforms, at 810 nm and 530nm illumination. The protocol comprised 3 minutes of baseline recording, 15 minutes recording of NTG effect, 2 minutes of arterial occlusion and the following 3 min reactive hyperemia. Two PPG signals were acquired from glabrous skin of the middle finger …

Temporal and Spatial Evolution of Cortical Blood Flow in the Penumbra of Venous Infarcts

2001

A cortical venous infarction model has been evaluated regarding the temporal and spatial evolution of regional flow reduction. Two cortical veins were occluded photochemically with rose bengal and fiberoptic illumination. Seven rats served to demonstrate effects on regional cortical blood flow using laser Doppler scanning. After two-vein occlusion, there was a widespread reduction of flow that gradually deteriorated after vein occlusion when regional cortical flow in a 3.5 x 7.0 mm window: after 15 min it had decreased to 57.8% ± 8.0%, and after 75 min it was 34.3% ± 5.4%. Infarct volumes as determined in 10 rats 5 days after two-vein occlusion had an average size of 3.6 ± 0.7 mm3. The data…

Mechanical rotational thrombectomy in long femoropopliteal artery and stent occlusion in COVID-19 patient: Case report

2021

Abstract Introduction Coronavirus disease-19 (COVID-19) has been increasingly associated with thromboembolic complications. COVID-19 infection has a thrombogenic potential for stents. Herein, we report a case of stent thrombosis in diabetic obese patient COVID-19 positive where was previously released a Multilayer Flow Modulator stent (MFM) for large popliteal aneurysm. Case report A 78-year-old male was referred to our hospital for fever and acute pain in the left leg. At history, the same patient had endovascular procedure for a large symptomatic popliteal aneurysm, treated through release of three MFM. The pulmonary CT scan showed COVID-19 infection with confirm of rhino-laryngeal swab. …