Navegando por Palavras-chave "Laser Doppler Imaging"

Agora exibindo 1 - 2 de 2
  • Imagem de Miniatura
    Item
    Acesso aberto (Open Access)
    Caracterização vascular periférica de pacientes portadores de glaucoma primário de ângulo aberto
    (Universidade Federal de São Paulo (UNIFESP), 2020-12-18) Muller, Elise Vivan Taniguchi [UNIFESP]; Paranhos Junior, Augusto [UNIFESP]; Universidade Federal de São Paulo
    Purpose: To evaluate peripheral microvascular characteristics of primary open-angle glaucoma (POAG) patients and healthy controls, along with endothelin-1 serum concentration and autoantibodies measurements. Patients and Methods: Subjects underwent a visual field test (Humphrey Visual Field Analyzer, Carl Zeiss, Dublin, USA), swept source optical coherence tomography (SS-OCT) (Deep Range Imaging OCT Triton, Topcon, Tokyo, Japan), nailfold capillaroscopy (NFC) (Stereo Microscope SZ40, Olympus, Tokyo, Japan), laser Doppler imaging (LDI) (Moor LDI-VR, Moor Instruments, Axminster, United Kingdom) and venous blood collection. Ophthalmic tests evaluated the presence and the stage of POAG and confirmed the absence of any abnormality among controls. NFC evaluated the presence and the number of microhemorrhages, tortuous capillaries, branched capillaries, dilated capillaries, mega-capillaries and bizarre capillaries, besides the number of capillary loops/mm and the deletion score; LDI measured fingertip blood flow (FBF) in four different timepoints and blood samples were evaluated for determination of serum endothelin-1 concentrations along with serum auto-antibodies measurements. Results: Sixty-eight subjects (43 patients with POAG and 25 healthy controls) were enrolled in the study. 65.1% of POAG patients presented with hemorrhages in the nailfold capillaroscopy versus 25.0% of healthy controls (p=0.003, chi-Square). There was a significant difference in the mean FBF at baseline in POAG patients vs. controls (293.6 ± 100.2 vs. 388.8 ± 52.0 perfusion units [PU]), respectively, p<0.001, mixed models), together with a significant difference in the mean FBF 10 and 20 minutes after cold stimulus in POAG patients in comparison to controls (p<0.001 for all comparisons, mixed models). However, nor the analysis of endothelin-1 concentrations (1.7 ± 1.4 vs. 1.6 ± 1.5 pg/ml, p=0.71, t-test) or the autoantibodies measurements (p>0.05 for all, chi-square) showed any difference between the groups. There was a positive correlation between basal FBF of LDI and retina nerve fiber layer (RNFL) measurements from SS-OCT (r=0.441, p=0.001, Pearson’s correlation coefficient), as well as between basal FBF and the mean deviation index of visual field (r=0.272, p=0.03, Pearson’s correlation coefficient). Conclusions: POAG patients presented significant peripheral microvascular abnormalities compared to healthy controls. This study supports the vascular theory associated to POAG.
  • Imagem de Miniatura
    Item
    Acesso aberto (Open Access)
    Laser Doppler Imaging para quantificação do fluxo sanguíneo de polpa digital em condições basais e após estímulo frio em pacientes com esclerose sistêmica
    (Sociedade Brasileira de Reumatologia, 2010-04-01) Correa, Marcelo Jose Uchoa [UNIFESP]; Perazzio, Sandro Felix [UNIFESP]; Andrade, Luiz Eduardo Coelho [UNIFESP]; Kayser, Cristiane [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)
    OBJECTIVES: The objective of this study was to investigate the dynamic behavior of the blood flow of the microvascular circulation of the fingertips before and after two cold stimuli (CS), using Laser Doppler Imaging with different intensities in patients with systemic sclerosis (SSc) and in healthy individuals. PATIENTS AND METHODS: Fourteen SSc patients (51.2 ± 5.5 years) with Raynaud's phenomenon and 12 healthy controls (44.8 ± 9.0 years) were included in this study. Two CS protocols (submersion of the hands in water at 10 ºC or 15 ºC for 1 minute) were performed on the same day. Mean fingertip blood flow (FBF) of four digits of the left hand was measured using LDI (Moor LDI-VR, Moor Instruments) at baseline and at 1, 4, 10, 25, and 40 minutes after CS. RESULTS: Baseline blood flow was significantly lower in both CS protocols in SSc patients when compared to controls (312.9 ± 102.7 vs 465.4 ± 135.4 PU, P = 0.006 at 15 ºC; 305.2 ± 121.0 vs 437.9 ± 119.8 PU; P = 0.01 at 10 ºC). In the control group, a significant decrease in FBF after CS, when compared to baseline, was observed 1 minute (P = 0.001) after CS at 15 ºC and at 1 (P = 0.005) and 25 minutes (P = 0.001) after CS at 10 ºC. In SSc patients, a significant decrease in FBF was observed in both CS protocols at 1, 4, and 10 minutes (P < 0.000; P = 0.002; P = 0.014, after CS at 15 ºC; P < 0.000; P = 0.004; P = 0.001, after CS at 10 ºC). CONCLUSIONS: Laser Doppler Imaging showed lower baseline fingertip perfusion and further reduction after CS in SSc patients compared to controls. Quantification of fingertip blood flow by LDI may be useful in the longitudinal monitoring of the disease status and therapeutic interventions in SSc.