Effect of 460 and 532 nm Laser Light on the Erythrocyte Deformability of Anaemic Blood Samples

This study investigated the effect of 460 nm and 532 nm laser irradiation on anaemic blood compared with normal samples at different exposure times. Blood smears were prepared to study the effect of laser irradiation on erythrocyte deformability. Irradiation of normal and anaemic blood samples with 460 and 532 nm laser light significantly changed erythrocyte deformability. The deformability of both the normal and anaemic blood samples increased as the exposure time increased. The analysis also revealed that erythrocyte deformability is greater in anaemic blood than normal blood.


Lasers
Stud ease of A ion. 16 at 70 s (4%) and 90 s (21%), respectively.However, for the anaemic samples, the highest deformability was observed at 50 s (12%) and 90 s (22%) when the samples were irradiated at 460 and 532 nm, respectively.At 90 s, irradiation of the blood samples at 532 nm resulted in greater deformability of both the normal and anaemic samples.The anaemic blood was affected more than the normal blood samples.Morphologically, both the 460 and 532 nm lasers caused erythrocyte deformability, especially for the anaemic samples.We assumed that the 532 nm laser would affect erythrocyte deformability more than the 460 nm laser, as the greatest deformability percentage was observed after 90 s of irradiation with 532 nm.This effect is because the effective tissue penetration is maximised at 532 nm compared to 460 nm.Haemoglobin, which acts as a chromophore, absorbs more photons at higher absorption bands from the 532 nm laser than the 460 nm laser. 9Thus, the effect is more prominent.Previously, it was shown that laser irradiation improved red blood cell deformability. 10,19,20However, the radiation must be administered at a therapeutic dose and not beyond that. 9The correct dose will stimulate a positive effect, but a higher dose will cause damage to and inhibit the erythrocytes. 21gure 3 shows images of blood smears from the normal blood samples.Figure 3A is the control unirradiated sample.The erythrocytes in this sample are in good condition.After irradiation for 50 s with the 460 nm laser (Figure 3B) and the 532 nm laser (Figure 3C), deformability of the erythrocytes was observed.Among the abnormal erythrocytes observed in the smears in Figure 3B and 3C are keratocytes, dacrocytes, boat-shaped cells and echinocytes.Irradiation at 532 nm affected the erythrocytes of the normal samples more than the 460 nm laser.
Figure 4 shows images of blood smears from the anaemic blood samples.Figure 4A is an image of the control unirradiated sample.The erythrocytes from this sample are in poor condition.Abnormal erythrocytes, such as echinocytes and dacrocytes, can already be observed.Irradiation for 50 s with the 460 nm and 532 nm lasers caused more deformability to the erythrocytes than in the control sample, as shown in Figure 4B and 4C, respectively.Among the abnormal erythrocytes observed in the smear in Figure 4B and 4C were schistocytes, acanthocytes, keratocytes, target cells and echinocytes.
Based on all the blood smears prepared, most of the abnormal cells observed were echinocytes, which are crenated compared to the other abnormal red blood cell variants.3][24] Therefore, a suitable laser irradiation parameter must be carefully chosen after weighing the benefits and the risks.
The red blood cell lifespan depends on an adequate oxidative stress response.Red blood cells are made of protein, and denaturation can occur when the local heat is high, which causes shear stress to the red blood cell membrane and thus changes the shape of the red blood cell.Echinocytes also form because of decreased ATP generation, resulting in the loss of water and potassium from the red blood cells.Red blood cells have deformable structures that allow them to recover their initial shape after passing through very small capillaries, which is an important and essential feature for their blood flow properties. 14,18,25,26However, if the alteration and deformation of the red blood cell is severe, it may affect the ability of the cell to function properly.Thus, maintaining the percentage of deformability of red blood cells after laser irradiation is crucial.

Figure 1 :
Figure 1: Percentage of erythrocyte deformability in normal and anaemic samples irradiated at 460 nm.

Figure 2 :
Figure 2: Percentage of erythrocyte deformability in normal and anaemic samples irradiated at 532 nm.

Figure 3 :
Figure 3: Images of blood smears from normal blood samples of A) control unirradiated sample; B) irradiated at 460 nm; and C) irradiated at 532 nm.