Clinical characteristics of acute acquired concomitant esotropia before and after the COVID-19 pandemic: a retrospective analysis.

PURPOSE: This study aimed to observe the clinical characteristics of acute acquired concomitant esotropia (AACE) patients in recent five years and to examine the changes in the proportion of AACE cases before and after the COVID-19 pandemic. METHODS: A retrospective study included 148 patients who underwent strabismus correction surgery for AACE between January 1, 2017, and December 31, 2021. The study analyzed the changing proportion of AACE cases before and after the COVID-19 pandemic and analyzed its clinical characteristics. RESULTS: Abnormalities in the worth 4 dot examination (both distance and near) were present in 134 cases (90.54%) before surgery, while 140 cases (94.59%) showed normal results after surgery. Near stereoacuity was present in 135 cases (91.22%). The near and distance deviations were (55.01 ± 18.77) PD and (57.30 ± 17.64) PD, respectively, and there was no significant difference between the two (p = 0.279). There were significant differences in the ratio of refractive status among different age groups (p < 0.001), while no statistically significant difference was observed in the ratio of refractive status for near deviation (p = 0.085) or distance deviation (p = 0.116). The proportion of AACE cases after the COVID-19 pandemic was significantly higher than that before the COVID-19 pandemic (p = 0.042). There was no statistically significant difference in the clinical characteristics between the two groups (p > 0.05). CONCLUSIONS: Myopia is the most common refractive status in AACE. More than half of patients had occupations that involved long hours of close work. The proportion of AACE cases increased significantly after the COVID-19 pandemic.

Frequency and associated factors of accommodation and non-strabismic binocular vision dysfunction among medical university students.

AIM: To investigate the frequency and associated factors of accommodation and non-strabismic binocular vision dysfunction among medical university students. METHODS: Totally 158 student volunteers underwent routine vision examination in the optometry clinic of Guangxi Medical University. Their data were used to identify the different types of accommodation and non-strabismic binocular vision dysfunction and to determine their frequency. Correlation analysis and logistic regression were used to examine the factors associated with these abnormalities. RESULTS: The results showed that 36.71% of the subjects had accommodation and non-strabismic binocular vision issues, with 8.86% being attributed to accommodation dysfunction and 27.85% to binocular abnormalities. Convergence insufficiency (CI) was the most common abnormality, accounting for 13.29%. Those with these abnormalities experienced higher levels of eyestrain (χ2=69.518, P<0.001). The linear correlations were observed between the difference of binocular spherical equivalent (SE) and the index of horizontal esotropia at a distance (r=0.231, P=0.004) and the asthenopia survey scale (ASS) score (r=0.346, P<0.001). Furthermore, the right eye's SE was inversely correlated with the convergence of positive and negative fusion images at close range (r=-0.321, P<0.001), the convergence of negative fusion images at close range (r=-0.294, P<0.001), the vergence facility (VF; r=-0.234, P=0.003), and the set of negative fusion images at far range (r=-0.237, P=0.003). Logistic regression analysis indicated that gender, age, and the difference in right and binocular SE did not influence the emergence of these abnormalities. CONCLUSION: Binocular vision abnormalities are more prevalent than accommodation dysfunction, with CI being the most frequent type. Greater binocular refractive disparity leads to more severe eyestrain symptoms.

Analysis of independent risk factors for acute acquired comitant esotropia.

AIM: To explore the risk factors for acute acquired comitant esotropia (AACE). METHODS: A retrospective cohort study was conducted by analyzing 83 patients (case group) with AACE who underwent strabismus correction surgery from January 1, 2021 to June 30, 2022. Totally 73 outpatient volunteers were recruited during the same period as the normal control group. The case group's binocular vision time, near and distance esotropia angle, and near stereo vision function were recorded, and the age, gender, refractive status, and best-corrected visual acuity (BCVA) of both groups were analyzed. Additionally, multiple logistic regression analysis was conducted using an eye usage condition questionnaire to determine the independent risk factors for AACE. RESULTS: In the case group, 61 patients (73.49%) had myopia, with a mean equivalent spherical power (SE) of -3.35±3.31 D (range: +2.75 to -10.62 D) of the right eye and -2.87±3.35 D (range: +2.75 to -11.12 D) of the left eye. The average duration of diplopia in the case group was 29.83±35.72mo, of which 80 patients (96.39%) were primarily with distance diplopia. The near and distance esotropia angle after wearing glasses were 52.36±20.95 prism degree (PD) and 56.71±19.54 PD, respectively, and there was no statistically significant difference between the two (t=1.38, P=0.169). The incidence of improper glasses wearing and unhealthy eye habits in the case group was significantly higher than those in the control group (P<0.05). Close-up work without glasses [ß=2.30, odds ratio (OR)=10, 95% confidence interval (CI) 2.35-42.51, P=0.002] and near work in supine position (ß=1.80, OR=6.02, 95%CI 3.29-11.02, P<0.001) were independent risk factors for AACE. CONCLUSION: Patients with AACE mainly present with distance diplopia, and there is a high degree of variation in myopia. Near work without wearing glasses and in supine position are independent risk factors for AACE.

Strabismus surgery for improving the quality of life of strabismus patients with thyroid-associated ophthalmopathy.

Thyroid-associated ophthalmopathy (TAO) is an autoimmune disease involving the ocular tissues that may require strabismus surgery treatment. Presently, little is known about the impact of strabismus surgery on the quality of life of such patients. Consequently, the aim of the present study was to explore the effect of strabismus surgery on the quality of life of strabismus patients with quiescent TAO. This was a prospective case-series study. Strabismus patients with TAO who were admitted to the First Affiliated Hospital of Guangxi Medical University for strabismus surgery from October 2011 to April 2016 were included in this study. The included patients were asked to complete the Graves' ophthalmopathy quality of life questionnaire (GO-QOL) before strabismus surgery and 6 weeks after the surgery, respectively. Preoperative and postoperative GO-QOL scores were compared using the paired samples t-test. The correlation between strabismus surgery and the quality of life was analyzed using Spearman correlation analysis. In total, 23 patients, with a mean age of 49.04 years old, were included in the study. Compared to the preoperative GO-QOL scores, the postoperative scores of these patients for visual function (43.04 vs 73.50, P < .001) and psychosocial function (40.13 vs 72.93, P < .001) were both significantly increased. The greater the preoperative angle of misalignment of the eyes, the worse the psychosocial function (r = -0.433, P = .039). Strabismus surgery can significantly improve the quality of life of strabismus patients with quiescent TAO.

Universal understanding of self-healing and transformation of complex structured beams based on eigenmode superposition.

The self-healing property of laser beams with special spatial structures is of great interest. We take the Hermite-Gaussian (HG) eigenmode as an example, theoretically and experimentally investigating the self-healing and transformation characteristics of complex structured beams composed of incoherent or coherent superposition of multiple eigenmodes. It is found that a partially blocked single HG mode can recover the original structure or transfer to a lower order distribution in the far field. When the obstacle retains one pair of edged bright spots of the HG mode in each direction of two symmetry axes, the beam structure information (number of knot lines) along each axis can be restored. Otherwise, it will transfer to the corresponding low-order mode or multi-interference fringes in the far field, according to the interval of the two most-edged remaining spots. It is proved that the above effect is induced by the diffraction and interference results of the partially retained light field. This principle is also applicable to other scale-invariant structured beams such as Laguerre-Gauss (LG) beams. The self-healing and transformation characteristics of multi-eigenmode composed beams with specially customized structures can be intuitively investigated based on eigenmode superposition theory. It is found that the HG mode incoherently composed structured beams have a stronger ability to recover themselves in the far field after occlusion. These investigations can expand the applications of optical lattice structures of laser communication, atom optical capture, and optical imaging.

Observation on the curative effect of horizontal rectus transposition combining recess-resect treatment on monocular elevation deficiency with horizontal strabismus.

Purpose: To explore the clinical effect of horizontal rectus transposition combining recess and resect treatment on monocular elevation deficiency (MED) with horizontal strabismus. Methods: Ten patients (10 eyes) scheduled to undergo horizontal rectus transposition combining recess-resect surgery to treat MED with horizontal strabismus in the ME Department of Ophthalmology of the First Affiliated Hospital of Guangxi Medical University between July 2016 and February 2022 were included in the study. The degree of vertical and horizontal prism strabismus, the grading of upper movement of the paralyzed eye, and the improvement of binocular vision were evaluated before and after the surgery. Results: Horizontal rectus transposition combined with recess and resect treatment was used to treat 10 patients with MED combined with horizontal strabismus. A good curative effect was seen in eight patients. The differences in the degree of vertical strabismus, the degree of horizontal strabismus, and the movement function of the paretic eyes before and after surgery were significantly different (all P < 0.05). The binocular haplopia function in six patients was reconstructed in the primary position after surgery. Conclusion: Horizontal rectus transposition combining recess-resect is easy to perform, and the number of recti involved in the surgery is small. This approach can effectively correct the eye position, improve eye movement, and reconstruct binocular vision in patients with MED by combining horizontal strabismus.

Effect of the base-out recovery point as the surgical target for acute acquired comitant esotropia.

PURPOSE: To evaluate the treatment efficacy of the preoperative base-out recovery point as the surgical target angle for acute acquired comitant esotropia. METHODS: Prospective study. Twenty-two patients with acute acquired comitant esotropia (AACE) underwent strabismus surgery based on the target angle of the preoperative base-out recovery point. The postoperative deviation, positive fusional vergence, and negative fusional vergence were evaluated and compared with those of 23 normal individuals. RESULTS: The mean follow-up period was 18.68 ± 19.48 months. At the last follow-up, 19 (86.4%) of 22 subjects had orthophoria, whereas 3 (13.6%) had minimal esophoria. The postoperative angle of deviation was significantly smaller than the preoperative angle of deviation at near (P < 0.001) and distance (P < 0.001). Postoperative sensory fusion was significantly better than preoperative fusion at near (P < 0.001) and distance (P < 0.001). The postoperative stereoacuity improved significantly after the surgery at near (P < 0.001) and distance (P < 0.001). Compared with the controls, the convergence and divergence amplitudes in the AACE patients were similar at distance (P > 0.05) but were still narrower at near (P < 0.001). CONCLUSION: Good alignment and binocular balance were obtained with the surgical target angle of the base-out recovery point in AACE.

Corneal endothelial cell density and morphology and central corneal thickness in Guangxi Maonan and Han adolescent students of China.

AIM: To investigate the corneal endothelial cell density and morphology and central corneal thickness in the Guangxi Maonan and Han adolescent students of China. METHODS: Noncontact specular microscope (Topcon SP3000P, Tokyo, Japan) was performed in 133 adolescent students of Maonan nationality (M:F 54:79) and 105 adolescent students of Han nationality (M:F 50:55), 5 to 20y of age, who were randomly selected from 3 schools in Huanjiang Maonan Autonomous County of Guangxi Zhuang Autonomous Region of China. Parameters studied included endothelial cell density, mean cell area, coefficient of variation in cell size, percentage hexagonality and central corneal thickness. RESULTS: Endothelial cell density, mean cell area, coefficient of variation in cell size, percentage hexagonality and central corneal thickness in the study population were (2969.50±253.93) cells/mm(2), (339.23±29.44) µm(2), (29.96±4.07) %, (64.58±9.41) % and (523.71±32.82) µm in Maonan and (2998.26±262.65) cells/mm(2), (336.11±30.07) µm(2), (29.89±5.03) %, (64.91±11.64) % and (524.39±33.15) µm in Han, respectively. No significant differences were observed in endothelial cell density, mean cell area, coefficient of variation in cell size, percentage hexagonality and central corneal thickness between Maonan and Han (P=0.615, 0.659, 0.528, 0.551, 0.999). In Maonan and Han, we found age was negatively correlated with endothelial cell density and percentage hexagonality and positively correlated with mean cell area and coefficient of variation in cell size. Negative correlation was also found between central corneal thickness and age in Han, whereas no correlation was found in Maonan. CONCLUSION: There were no differences between Maonan and Han in corneal endothelial cell density and morphology and central corneal thickness. In these two nationalities, there were statistically significant decrease in endothelial cell density and percentage hexagonality with increasing age and statistically significant increase in cell area and coefficient of variation in cell size with increasing age. Central corneal thinned with increasing age in Han, whereas difference did not attain statistical significance in Maonan.

[Retinal gene expression profiles of MNU-induced rat retinal degeneration treated with qijudihuangtang].

PURPOSE: Our previous studies demonstrated that qijudihuangtang, a compound of traditional Chinese medicine, protects from MNU (N-methy-N-nitrosourea)-induced rat retina photoreceptor injury. The current study was aimed to investigate protective effect of qijudihuangtang on the gene expression of retina in the same model. METHODS: Thirty 46-day-old female Sprague-Dawley rats were randomly divided into three groups (each group, n=10). The rats received a daily intragastric administration of qijudihuangtang in drug group, and 0.9% NaCl in model and normal groups for 4 days. On the fifth day, the rats in model and drug groups received a single intraperitoneal injection of 40 mg/kg body weight of N-methy-N-nitrosourea (MNU). Equivalent volume of 0.9% NaCl was injected to the rats of normal group. After 12 h of injection, all animals were sacrificed. Fresh retinas were used to extract total RNA, which was assayed by microarray and real time RT-PCR. The differentially expressed genes were also analyzed for the functional annotation and signal network mapping. RESULTS: There were 75 and 118 genes differently expressed (ratio > or = 2.0) in model group versus normal group and model group versus drug group, respectively. The former mainly included genes upregulated and the latter included most genes downregulated. These genes were mainly assigned to the categories binding transcription factor, signaling molecular, receptor, nucleic binding and extracellular matrix, and involved biological processes including signal transduction, development, immune and defense, apoptosis. The differential expressed genes contributed to MAPK signaling pathways, Toll-like receptor signaling pathway and apoptosis pathway. CONCLUSION: The gene expression in the early stage of MNU-induced rat retinal degeneration can be regulated significantly by the administration of qijudihuangtang. These changed genes were associated with specific functional groups.

Microarray expression analysis of the early N-methy-N-nitrosourea-induced retinal degeneration in rat.

The study was undertaken to investigate the gene expressions in N-methy-N-nitrosourea (MNU)-induced rat retinal degeneration (RD) by performing microarray analysis of retinal RNA at 12h. All rats were randomly divided into a normal group, a 12h model group and a 24h model group. Rats in the two model groups received a single intraperitoneal injection of 40 mg/kg body weight of MNU, while those in the normal group were injected with equivalent volume of physiological saline. After 12h and 24h of the injection, rats in each respective group were sacrificed, respectively. One eye of each animal was used for hematoxylin and erosin (H&E) staining, and fresh retinas of the other eye of each animal in the both normal group and 12h model group were used to extract total RNA, which was analyzed by microarray and real time RT-PCR. Retinal histological alteration was found in the 24h model group. There were 75 genes differently expressed (ratio > or =2.0), including 64 genes up-regulated and 11 genes down-regulated. Seven genes were assayed by real time RT-PCR and demonstrated the same alteration tendency as in microarray analysis. These genes that expressed differently mainly involved signal transduction, development, immune and defense, and apoptosis, etc. The major pathways were MAP-kinase signaling pathways, Toll-like receptor signaling pathway and apoptosis pathway involved. The results suggest that there are significant changes of gene expression in the early stage of MNU-induced RD. These microarray results provide clues to understand the molecular pathways underlying photoreceptor degeneration and indicate directions for future studies.

[Changes of NF-kappaB/I kappa B alpha in N-methyl-N-nitrosourea-induced retinal damage in rats].

OBJECTIVE: To observe the changes of nuclear factor-kappa B (NF-kappaB) in the course of N-methyl-N-nitrosourea (MNU)-induced apoptosis of rat retinal photoreceptor cells and investigate the mechanism of MNU-induced retinal damage. METHODS: A single intraperitoneal injection of 60 mg/kg MNU was given to 50-day-old female rats, which were sacrificed at different intervals after MNU treatment. The retinal damage was examined with optical microscopy and photoreceptor cell apoptosis detected by TUNEL assay. Western blotting was performed to analyze the changes in NF-kappaB. RESULTS: Pyknosis of the photoreceptor cell nuclei and disorientation of the outer segment of the photoreceptor layer was observed 24 h after MNU treatment, and the outer nuclear layer and photoreceptor layer were almost completely lost on day 7. Photoreceptor cell apoptosis peaked at 24 h, and in the apoptotic cascade, NF-kappaB p65 protein was only detected 12 and 24 h after MNU treatment, whereas the amount of I kappa B alpha, in contrast, markedly increased in the cytoplasm as well as in the nuclei. CONCLUSION: MNU-induced retinal damage might be mediated through the signaling pathway of NF-kappaB/I kappa B alpha.

[Protective effects of ligustrazine against photoreceptor cell injury induced by N-methyl-N-nitrosourea and its mechanism].

AIM: To study the protective effect of ligustrazine against photoreceptor cell injury induced by N-methyl-N-nitrosourea (MNU) in Sprague-Dawley (SD) rats. METHODS: Ligustrazine injections of different doses were injected intraperitoneally into 47-day female SD rats once a day and a single intraperitoneal injection of MNU 60 mg x kg(-1) was given to 50-day rats. At different intervals after MNU treatment,the animals were sacrificed. The apoptotic index of photoreceptor cells was calculated by TUNEL labeling at 24 h following MNU treatment; peripheral retinal damage was evaluated based on retinal thickness at the d 7 after MNU treatment, and the expression of c-jun and c-fos genes was detected by RT-PCR technique. RESULTS: Ligustrazine injection could remarkably increase total thickness of peripheral retina and decrease apoptotic index of photoreceptor cells induced by MNU in a dose-dependent manner. Compared with MNU-treated rats, the gene expression of c-jun and c-fos was time-dependently down-regulated in ligustrazine-treated group. CONCLUSION: Ligustrazine injection partially protects against MNU-induced retinal damage by down-modulating the expression of c-jun and c-fos genes to inhibit apoptosis of photoreceptor cells.

N-methyl-N-nitrosourea-induced apoptosis of photoreceptor cells in Sprague-Dawley rats via nuclear factor-kappaB.

BACKGROUND: Previous studies have showed that photooxidative stress can lead to down-modulation of nuclear factor-kappa B (NF-kappaB) activity causing apoptosis of cultured photoreceptor cells. This study aimed at investigating whether NF-kappaB was involved in photoreceptor cells apoptosis induced by N-methyl-N-nitrosourea (MNU) in rats. METHODS: A single intraperitoneal injection of 60 mg/kg MNU was given to 50-day-old female rats. At different intervals after MNU treatment, the animals were sacrificed. Retinal damage was examined by a light microscope. The apoptotic index of the photoreceptor cells was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL). NF-kappaB was analysed by Western blot and Transcriptin Factor Assay Kits. RESULTS: The pyknosis of the photoreceptor nuclei and the disorientation of the outer segment of the photoreceptor layer was seen after MNU treatment for 24 hours. The outer nuclear layer and photoreceptor layer were almost completely lost at 7 days. Photoreceptor cells apoptosis reached the peaked value at 24 hours. In apoptotic cascade, the protein levels of NF-kappaB p65 were only detected after MNU treatment for 12 and 24 hours in the nucleus. Conversely, the amounts of IkappaBalpha were markedly increased in the cytoplasm as well as in the nucleus. The activity of NF-kappaB p65 in the nucleus was down-modulated in the end. CONCLUSIONS: MNU-induced photoreceptor cell destruction was attributed to the apoptotic process by down-regulating the activation of NF-kappaB p65.

Tetramethylpyrazine protected photoreceptor cells of rats by modulating nuclear translocation of NF-kappaB.

AIM: To evaluate the effect of tetramethylpyrazine (TMP) injection on retinal damage induced by N-methyl-N-nitrosourea (MNU) in rats and on nuclear factor-kappa B (NF-kappaB) family members. METHODS: Female Sprague-Dawley (SD) rats were randomly divided into groups: (i), control group; (ii), model group; and (iii), TMP-injection groups, in which the rats were subdivided into 40 mg/kg, 80 mg/kg and 160 mg/kg groups. Drugs were injected ip into 47-day-old SD rats once a day. At 50 days of age, all rats in the model group and drug groups also received a single ip injection of 60 mg/kg MNU. Rats in group 1 received ip injection of physiological saline. All rats were killed at different times after MNU or physiological saline treatment. The apoptotic index of photoreceptor cells was calculated by TUNEL labeling; retinal damage was evaluated based on retinal thickness and the expression of NF-kappaB family members was detected by Western blot. RESULTS: TMP injections, in a dose-dependent manner, suppressed photoreceptor cell apoptosis and decreased its loss in the peripheral retina. As compared with the MNU-treated group, TMP injection at a dose of 160 mg/kg also time-dependently upregulated the NF-kappaB/p65 protein level in the nucleus and downregulated the IkappaBalpha protein level in the cytoplasm. However, no protective effect of TMP injection on MNU-induced central retinal damage was found. CONCLUSION: TMP injection partially protects against MNU-induced retinal damage by upregulating the nuclear translocation of p65 to inhibit photoreceptor cells apoptosis.