Effects of low- and high-level pulsed Nd:YAG laser irradiation on red blood cells and platelets indices of albino rats in vitro

Abstract

Objectives Erythrocyte cell membrane and enclosed haemoglobin content being a target with a consistent wavelength in the laser absorption spectrum. In this study, intension was made to clarify whether irradiation with high energy densities of pulsed laser; Neodymiumdoped yttrium aluminium garnet (Nd:YAG) with different pulse rates can improve the haemorheological parameters of red blood cells (RBCs) and platelets.
Methods Pulsed Nd: YAG laser (λ = 532 nm) performance was measured and calibrated to either low (LLLR) or high (HLLR) level laser radiation schemes. Albino rat blood samples were collected and irradiated with low- and high-level energy laser (Fluence = 2.38–47.77 J/cm2). Complete blood picture was done for all samples and blood parameters were assessed and compared for both control and irradiated groups using paired t-test.
Results Blood parameters like haemoglobin (HGB) and haematocrit (HCT) increased significantly (P ≤ 0.05) by low laser fluence 2.38–4.77 J/cm2. High-level laser irradiation significantly decreased (P ≤ 0.05) RBCs distribution width (RDW) and platelet distribution width (PDW) for fluencies from 11.94/cm2 to 47.77 J/cm2. Stained blood films showed improved rheological properties of both RBCs and platelets irradiated with laser energy as low as 7.16 J/cm2. Both LLLR and HLLR fluencies significantly decreased (P ≤ 0.05) and normalized platelets aggregatory properties.
Conclusion High-level laser irradiation reduced RBC deformability, aggregability and platelet aggregation resulting in improvements of cell membrane revitalizing, decreased viscosity and stress adaptation. Laser also enhanced both RBC and platelet life span with high-energy fluencies. HLLR using pulsed Nd:YAG is potentially a useful technique for the clinical intervention of many blood disorders.
Keywords Nd:YAG laser, RBCs indices, platelets aggregation