ABSTRACT
Objective To investigate the effects of blue light on the thickness of corneal epithelium and full-thickness of the cornea in mice by optical coherence tomography angiography (OCTA).Methods Totally 40 mice were collected and randomly divided into experimental group and control group,with 20 mice in each group,and the experimental mice were raised in the blue light environment from 8 to 16 hours per day,while the controls were reared in normal environment.Then the thickness of corneal epithelium and full-thickness of the cornea in both groups were measured by OCTA before irradiation and one week,two weeks,one month,two months and three months after irradiation,respectively.Results Compared with pre-irradiation,the thickness of corneal epithelium of all regions did not change significantly in both groups at 1 week,2 weeks,and 1 month after irradiation,and the differences were not statistically significant (all P ＞ 0.05).Compared with before irradiation,the corneal epithelium thickness of the control group at 2 months and 3 months after irradiation did not change significantly,and there was no significant difference (both P ＞ 0.05).Compared with the control group,the corneal epithelium at central,nasal 5 mm,inferior 5 mm,and temporal 5 mm regions in the experimental group were significantly thickened,and the differences were statistically significant (all P ＜0.05).Three months after irradiation,compared with the control group,the thickness of corneal epithelium in the central and inner regions of the cornea and nasal 6 mm and temporal 6 mm regions of the experimental group were significantly thickened,and the differences were statistically significant (all P ＜ 0.05).There was no significant change in the corneal full thickness between the experimental group and the control group before irradiation and 1 week,2 weeks,1 month,2 months,and 3 months after irradiation,and the differences were not statistically significant (all P ＞ 0.05).Furthermore,the difference in the extremum value of corneal epithelial thickness,namely the maximum and the minimum,was significantly different in both groups (P ＜ 0.05),but the difference in the extremum value of the full-thickness of the cornea was not significant in the two groups (P ＞ 0.05).Conclusion The blue light can change the thickness of corneal epithelium in mice,and the change of the central region is obvious,but the full-thickness of the cornea do not significantly change in a short term.
ABSTRACT
Objective To explore the effects of benzalkonium bromide and citalopram on the corneal epithelium and corneal thickness of mice using optical coherence tomography angiography (OCTA).Methods Together 60 mice were randomly divided into 5 groups (group A,B,C,D and E;n =12),with group A left untreated,group B receiving PBS eye drops,group C given benzalkonium bromide eye drops,group D undergoing intraperitoneal administration of citalopram suspension,and group E treated with combination of benzalkonium bromide eye drops and citalopram suspension.After 2 weeks,OCTA was applied for corneal subarea,followed by measurement of the thickness of corneal epithelium and full-thickness of the cornea of all mice,and then the mean values were calculated.Results The thickness of corneal epithelium and fullthickness of the cornea was (66 ±7) μm and (141 ± 11) μm in the group A,(66 ± 8) μm and (140 ± 12) μm in the group B and D,(73 ± 10) μm and (141 ± 14) μm in the group C,(76 ± 12) μm and (141 ± 15) μm in the E group,respectively.And there was no significant difference in the thickness of corneal epithelium and full-thickness of the cornea before treatment and 2 weeks after treatment in the group A,B and D (all P ＞ 0.05),but both variables were markedly thickened in group C and E 2 weeks after treatment,and the difference was statistically significant (all P ＜0.05).Moreover,the increased levels on the both variables in the group E was higher than those in the group C 2 weeks after treatment,and the difference was statistically significant (both P ＜ 0.05).The average thickness of corneal epithelium and full-thickness of the cornea in the group C and E were significantly thickened after treatment,and the difference was statistically significant (all P ＜ 0.05).The average values of both variables in the group C and E were obviously larger than those in the group A,and the difference was statistically significant (all P ＜ 0.05).Conclusion Citalopram alone has no significant effects on the corneal thickness by OCTA,whereas both the thickness of corneal epithelium and fullthickness of the cornea tend to thicken by benzalkonium bromide treatment,which has a synergistic effect on corneal thickening with citalopram.
ABSTRACT
Objeetive To compare the thickness of corneal epithelium and full-thickness of the cornea among New Zealand rabbits,cats and the human using optical coherence tomography angiography (OCTA) technology as to explore the morphological basis for different animals as experimental models of xenocorneal transplantation.Methods Totally selected 12 New Zealand male rabbits and 12 male cats were included in this study and divided into group A and B.Then the thickness of corneal epithelium and full-thickness of the cornea of both eyes in the two groups were measured with OCTA technology,and according to the distance from the center of the cornea,the cornea was divided into 17 areas by System software.The center of the cornea was a diameter of 2 mm around the center of the cornea,with the inner ring and outer ring of 5 mm and 6 mm in diameter,respectively;and the inner and outer ring region was again divided into 8 areas,including superior side (S),superior nose side (SN),nasal side (N),inferior nose side (IN),inferior side (I),inferior temporal side (IT),temporal side (T),superior temporal side (ST).Then the thickness of corneal epithelium and full-thickness of the cornea in each region were measured for comparing the difference of New Zealand rabbits' and cats' corneal thickness with the human's.Results The thickness of corneal epithelium and full-thickness of the cornea of cats were both thicker than those of rabbits.The full-thickness of the cats' cornea became thinner from the central to the peripheral side,and the difference of thickness between the T5,ST5,S5,SN5,N5 areas and the central of the cornea was statistically significant (all P ＜0.05);the thickness of corneal epithelium in the ST5,S5,SN5 areas was significantly thicker than the central area (all P ＜0.05);And this was true of the rabbits' full-thickness of the cornea,and the difference in the full-thickness of the cornea between the T5,IT5,IN5,N5,T6,N6 area and the central region was statistically significant (all P ＜ 0.05);meanwhile there were also significant difference in the thickness of corneal epithelium between the ST5,S5,SN5,ST6,S6,SN6 areas and the central area (all P ＜ 0.05).Additionally,there were significant differences in the thickness of corneal epithelium and full-thickness of the cornea between the two experimental animals and humans (all P ＜ 0.05).Conclusion The cornea of cats possesses similar regions in corneal full-thickness and epithelial thickness as well as the distribution to human cornea,so cats have superiority to the rabbits for the potential donor of xenocorneal transplantation in human beings.