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AIM: To observe the therapeutic effect of the diquafosol sodium combined with intense pulsed light(IPL)on meibomian gland dysfunction(MGD)dry eye after refractive surgery.METHODS:A total of 64 patients(128 eyes)with MGD dry eye diagnosed within 6mo after laser corneal refractive surgery in our hospital from March 2021 to December 2021 were selected. They were randomly divided into control group and experimental group. A total of 33 patients(66 eyes)in the control group were treated with sodium hyaluronate combined with IPL, and 31 patients(62 eyes)in the experimental group were treated with diquafosol sodium combined with IPL. Ocular symptom scores were performed before each IPL treatment in both groups to examine non-invasive tear breakup time(NIBUT), tear meniscus height, lipid layer grade of tear film, meibomian gland deletion rate and uncorrected visual acuity.RESULTS:After IPL treatment, ocular symptom scores and meibomian gland deletion rate score of two groups were decreased continuously. NIBUT, tear meniscus height and lipid layer grade of tear film were increased continuously, and there was no significant change in uncorrected visual acuity. NIBUT of patients in the experimental group was better than that in the control group before the third IPL treatment(6.24±0.27s vs. 5.51±0.24s, P=0.046).CONCLUSIONS:Both diquafosol sodium and sodium hyaluronate combined with IPL showed good therapeutic effect on MGD dry eye, but there was no significant difference in the short-term efficacy between the two groups.
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AIM: To observe the effect of eccentricity of the optical treatment zone on retinal defocus after wearing orthokeratology lens for 12mo.METHODS: In this case-control study, a total of 120 myopic patients(120 eyes)who completed the fitting in our hospital from March 2021 to September 2021 and insisted on wearing orthokeratology lenses for 12mo were selected. According to the eccentricity after wearing lenses for 12mo, they were divided into the low eccentricity group(<0.5mm, 58 cases, 58 eyes)and the moderate and high eccentricity group(≥0.5mm, 62 cases, 62 eyes). The optical treatment zone diameter(OTZD), eccentricity, axial length(AL), pupil diameter(PD)and refraction difference value(RDV)were evaluated after 12mo of wearing orthokeratology lenses, and the correlation between RDV and eccentricity was analyzed.RESULTS: After wearing orthokeratology lenses for 12mo, AL growth and RDV at 30°～40° and 40°～53° from the fovea were significantly lower in the moderate and high eccentricity group than in the low eccentricity group(all P<0.05). In all patients, RDV at 40°～53° from the fovea was positively correlated with AL growth and OTZD(rs=0.544, 0.333, both P<0.01), and negatively correlated with eccentricity(rs=-0.224, P=0.014).CONCLUSION: Peripheral retinal defocus is related to eccentricity and OTZD after wearing orthokeratology lenses. The greater eccentricity and the smaller OTZD within a certain range can induce more peripheral retinal myopic defocus, leading to a better control of AL growth.
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Fermented Chinese medicine has long been used. Amid the advance for preservation of experience, the connotation of fermented Chinese medicine has been enriched and improved. However, fermented Chinese medicine prescriptions generally contain a lot of medicinals. The fermentation process is complicated and the conventional fermentation conditions fail to be strictly controlled. In addition, the judgment of the fermentation end point is highly subjective. As a result, quality of fermented Chinese medicine is of great difference among regions and unstable. At the moment, the quality standards of fermented Chinese medicine are generally outdated and different among regions, with simple quality control methods and lacking objective safe fermentation-specific evaluation indictors. It is difficult to comprehensively evaluate and control the quality of fermented medicine. These problems have aroused concern in the industry and also affected the clinical application of fermented Chinese medicine. This article summarized and analyzed the application, quality standards, and the modernization of fermentation technology and quality control methods of fermented Chinese medicine and proposed suggestions for improving the quality standards of the medicine, with a view to improving the overall quality of it.
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Medicine, Chinese Traditional , Reference Standards , Quality Control , FermentationABSTRACT
AIM: To compare the visual quality between smart pulse technology-assisted(SPT)transepithelial photorefractive keratectomy(TransPRK)of 1 050Hz ablation frequency and small incision lenticule extraction(SMILE)for myopia and astigmatism.METHODS: A total of 138 cases(248 eyes)who received corneal refractive surgery in the Eye Hospital of Chengdu University of TCM were enrolled from July 2020 to January 2021. The patients were divided into TransPRK group(64 cases, 123 eyes)and SMILE group(74 cases, 125 eyes)according to the surgical method. The follow-up duration was 6mo. Strehl ratio(SR)and high-order aberration at 6mm pupil diameter measured by Sirius anterior segment integrated analyzer and LogMAR visual acuity were recorded at different preoperative and postoperative time points.RESULTS: The uncorrected visual acuity(UCVA)of TransPRK group was worse than SMILE group at 1wk and 1mo after surgery(all P<0.05), but UCVA was better in TransPRK group at 6mo after surgery(P<0.05). SR in TransPRK group was lower than that in SMILE group at 1wk and 1mo after surgery(all P<0.05). There was no significant difference in SR between the two groups at 3 and 6mo after surgery(P=0.968, 0.433). At 1wk after surgery, there was no significant difference in coma between the two groups(P=0.554). At 1, 3, and 6mo after surgery, coma in the TransPRK group was lower than that in SMILE group(all P<0.05). At 1wk, 1 and 3mo after surgery, the trefoil aberration in TransPRK group was higher than that in SMILE group(all P<0.05). At 6mo after surgery, there was no significant difference in trefoil aberration between the two groups(P=0.167). At 6mo after surgery, UCVA of TransPRK group and SMILE group were -0.13±0.05 and -0.11±0.08, respectively, which were better than the best corrected visual acuity(BCVA)before surgery(-0.07±0.05 and -0.07±0.05; all P<0.05). Furthermore, the SR of both groups was higher than that before surgery(all P<0.05).CONCLUSION: Both SPT-assisted TransPRK of 1 050Hz ablation frequency and SMILE can achieve better visual acuity after refractive surgery, while SMILE has better visual quality at 1wk and 1mo after surgery. However, SPT-assisted TransPRK of 1 050Hz ablation frequency has better visual acuity at 6mo after surgery than SMILE, and the coma is smaller.
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AIM: To explore the current research progress, hot spots and future development trends of myopia in children and adolescents at home and abroad, thus providing references for the further research on the field.METHODS: Using China National Knowledge Infrastructure(CNKI)and Web of Science(WOS)as data sources, the literature on myopia in children and adolescents from January 1, 2003 to December 31, 2022 was collected. Visual analyses were conducted based on the quantity of the published articles, authors, publishing institutions, journals as well as keyword co-occurrence, clustering, timeline graph and emergence by using the VOSviewer and CiteSpace.RESULT: The number of publications on myopia research has increased steadily both articles in Chinese and English. Xian-Gui He and Saw, Seang-Mei have published the most papers, and the Chinese Journal of School Health and Investigative Ophthalmology & Visual Science published the most related articles. Shanghai Eye Disease Prevention and Treatment Center, and Sun Yat-sen University are the institutions with the most publications in the area. Clinical observation is the main focus of research both domestically and internationally, with orthokeratology, outdoor activities, axial length, prevalence, and influencing factors attracting much attention.CONCLUSION: Current research on myopia in children and adolescents focuses on the epidemiology, intervention measures, and biological parameters of the condition. Future research on myopia epidemiology is likely to become a major focus of research in this area.
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AIM: To observe and compare the changes in retinal peripheral refraction and aberrations after femtosecond laser-assisted laser in situ keratomileusis(FS-LASIK)versus small incision lenticule extraction(SMILE)for myopia correction.METHODS: A total of 71 patients(71 eyes)with myopia who underwent FS-LASIK from October 2022 to April 2023 in our hospital were selected as the FS-LASIK group, and 80 patients(80 eyes)with myopia who underwent SMILE were selected as the SMILE group. All patients underwent corneal wavefront aberration measurement and multispectral refractive topography preoperatively and 3mo postoperatively, as well as refraction difference value(RDV)in the range of 0°～10°, 10°～20°, 20°～30°, 30°～40°, and 40°～53° in the annulus of the retina, which were recorded as RDV-(0°～10°), RDV-(10°～20°), RDV-(20°～30°), RDV-(30°～40°), and RDV-(40°～53°). The results of two groups of patients were compared.RESULTS: No significant differences were observed in RDV-(0°～10°), RDV-(10°～20°), RDV-(20°～30°), RDV-(30°～40°), RDV-(40°～53°)between the two groups at 3mo post-operation(all P>0.05). Furthermore, the RDV-(20°～30°), RDV-(30°～40°)and RDV-(40°～53°)of the two groups at 3mo postoperatively were all significantly lower than those preoperatively(all P<0.05). The changes in coma(horizontal)and spherical aberration(SA)at 3mo postoperatively were smaller in the SMILE group [0.106(0.056, 0.171)and 0.115(0.081, 0.182)μm] than in the FS-LASIK group [0.206(0.104, 0.355)and 0.197(0.128, 0.254)μm](Z=-4.170, -5.016, all P<0.05). A negative correlation was found between postoperative SA and postoperative RDV-(10°～53°)(rs=-0.205, -0.181, -0.226, -0.244, all P<0.05).CONCLUSION: Both FS-LASIK and SMILE reduced retinal hyperopic defocus in the peripapillary macular range of 20°～53° eccentricity, and the postoperative changes in coma(horizontal)and SA were smaller with SMILE than with FS-LASIK. There was a certain correlation between postoperative SA and postoperative retinal peripheral defocus.
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Since the implementation of drug registration in China, the classification of Chinese medicine has greatly met the needs of public health and effectively guided the transformation, inheritance, and innovation of research achievements on traditional Chinese medicine(TCM). In the past 30 years, the development of new Chinese medicine has followed the registration transformation model of " one prescription for single drug". This model refers to the R&D and registration system of modern drugs, and approximates to the " law-abiding" medication method in TCM clinic, while it rarely reflects the sequential therapy of syndrome differentiation and comprehensive treatment with multiple measures. In 2017, Opinions on Deepening the Reform of Review and Approval System and Encouraging the Innovation of Drugs and Medical Devices released by the General Office of the CPC Central Committee and the General Office of the State Council pointed out that it is necessary to " establish and improve the registration and technical evaluation system in line with the characteristics of Chinese medicine, and handle the relationship between the traditional advantages of Chinese medicine and the requirements of modern drug research". Therefore, based on the development law and characteristics of TCM, clinical thinking should be highlighted in the current technical requirements and registration system of research and development of Chinese medicine. Based on the current situation of registration supervision of Chinese medicine and the modern drug research in China, the present study analyzed limitations and deficiency of " one prescription for single drug" in the research and development of Chinese medicine. Additionally, a new type of " series prescriptions" was proposed, which was consistent with clinical thinking and clinical reality. This study is expected to contribute to the independent innovation and high-quality development of the TCM industry.
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China , Drugs, Chinese Herbal/therapeutic use , Medicine, Chinese Traditional , Prescriptions , Public HealthABSTRACT
In recent years, only a small number of new Chinese medicines have been approved for marketing, which has embodied the bottleneck in the development of the Chinese medicine industry. To tackle this problem, the National Medical Products Administration has issued a series of regulations and technical requirements. In the context of new regulations, this study deeply explored the research and development strategies of new Chinese medicines under the guidance of the new classification of drug registration, and discussed the key technical issues in the research and development.
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China , Drugs, Chinese Herbal , Medicine, Chinese Traditional , Pharmaceutical Preparations , ResearchABSTRACT
To learn the current situation and strengthen the management of national standards for Chinese medicinal materials, we sorted out the relevant national standards. According to incomplete statistics, there are 1 185 kinds of Chinese medicinal materials, including 1 024 kinds of plant medicines, 106 kinds of animal medicines, and 54 kinds of mineral medicines, in addition to ethnic medicinal materials with different functions. The relevant standards include 819 Pharmacopoeia standards, 342 standards issued by the Ministry of Health or National Medicinal Products Administration, 7 standards for new medicinal materials, and 17 standards for imported medicinal materials. In this paper, the sources of standards as well as the distribution of families and genera and the distribution of medicinal parts of medicinal materials are analyzed. The suggestions are as follows:(1)to improve the coordination among different national standards of Chinese medicinal materials;(2)to improve the standardization and controllability of relevant standards;(3)to revise the issued standards for Chinese medicinal materials(including Tibetan, Uygur, and Mongolian medicinal materials).
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Animals , Humans , Asian People , China , Drugs, Chinese Herbal , Medicine, Chinese Traditional , Plants, Medicinal , Reference StandardsABSTRACT
In order to clarify the origin of Houzao, this paper summarizes and analyzes the related literatures, on-site investigation and experimental research results of Houzao. The results showed that Houzao coming from India is the gastric bezoars of Capra hircus. It is suggested that the name of the standard of imported Houzao should be changed to "Yangchangzao". At the same time, the local standards of Houzao should be abolished, and the standards of local processing procedures and the specifications of related Chinese patent medicines should be revised. In addition, according to literature research, the first detailed description of the origin and characters of Houzao may be Jie-sheng Shi's discussion in Shaoxing Medical Journal in 1920.
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· AIM:To evaluate the safety and efficacy at early stage after femtosecond laser-assisted excimer laser in situ keratomileusis (FS-LASIK) combined with collagen cross-linking.· METHODS:Totally 30 myopia patients (60 eyes) received FS-LASIK combined with collagen cross-linking from July 2016 to August 2017 in our hospital were tested the uncorrected visual acuity (UCVA),Ks,Kf,surface regular index (SRI),surface asymmetry index (SAI) by corneal topography (TMS) preoperatively,1,3mo after operation.The corneal compensated intraocular pressure (IOPcc),Goldmann correlated IOP value (IOPg),corneal resistance factor (CRF),corneal hysteresis (CH) tested by ocular response analyzer (ORA) were also observed.Ziemer Galilei Dual Scheimpflug Analyzer detected the anterior diopter and the corneal thickness.Endothelial cell density were examined.· RESULTS:The postoperative UCVA remained beyond 0.8 including 26 eyes (43％) of 1d,55 eyes (92％) of 1mo,50 eyes (83％) of 3mo.IOPcc,IOPg,CRF,CH at postoperative 1mo significantly decreased comparing with preoperative (P＜0.01).IOPcc,IOPg,CRF,CH at postoperative 3mo did not change significantly comparing with 1mo (P＞0.05).The corneal topographic map parameters of Ks and Kf significantly decreased at postoperative 1mo (P ＜ 0.01),while SRI and SAI increased significantly (P＜0.01) on comparison of 1mo and preoperative.Ks of postoperative 3mo was significantly higher than that of 1 mo (P＜0.05),while Kf did not change significantly (P＞ 0.05).There was a significant decrease in SRI and SAI between 3mo and 1mo after operation (P＜ 0.05).In Galileo analysis on comparison of 3mo and 1mo,Sim Ks,Sim Kf had 0.94D,0.95D growth and the front and back surface value of Kf increased more at 3mo postoperative (P＜0.01),while Ks was no significant difference (P＞ 0.05).There was no statistically significant difference in corneal thickness between the central point and the thinnest point (P＞ 0.05).There was no significant endothelial cell loss throughout follow up (3059.95±247.87/mm2 vs 3052.87± 267.71/mm2;t=0.279,P＞0.05).· CONCLUSION:Refractive corneal surgery combined with collagen cross linking for high degree,thin cornea,uneven thickness of the cornea,topographic anomalies except for the patients with keratoconus,play a role in stabilizing corneal shape and increasing corneal biomechanics early.
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AIM:To evaluate the influence on corneal biomechanics after small incision lenticule extraction (SMILE) and Femto LDV laser flapping in laser in situ keratomileusis(FS-LASIK).METHODS:Preoperatively,1mo after surgery,101 patients (202 eyes) with myopia in each group respectively by SMILE and FS-LASIK were examined by ocular response analyzer (ORA).Parameters were compared between postoperative (1 mo) and preoperative.Comparisons included the corneal thickness and corneal compensated intraocular pressure (Iopcc),Goldmann correlated lOP value(Iopg),corneal resistance factor (CRF),corneal hysteresis (CH).RESULTS:SMILE group:IOPcc,IOPg (1mo postoperatively,13.84 ± 2.22,10.81 ± 2.52mmHg) significantly changed comparing with preoperative (16.15±2.90,15.95±3.08mmHg;t=-13.58,-32.91;both P＜0.01).CRF and CH (1 mo postoperatively,7.52±1.41,8.66±1.19mmHg) significantly changed comparing with preoperative (10.72± 1.61,10.60± 1.43;t=-41.21,-24.03;both P＜0.01).The difference were 3.19±1.10,1.93± 1.14mmHg respectively.FS-LASIK group:Iopcc and Iopg (1mo postoperatively,13.99 ± 2.33,10.10 ± 2.55mmHg) significantly changed comparing with preoperative (15.88±3.29,14.86±3.34mmHg;t=-10.09、-23.00;both P＜0.01).CRF,CH (1mo postoperaturely,6.68 ± 1.14,7.90 ± 1.27mmHg) significantly changed comparing with preoperative (9.93 ± 1.85,9.98 ± 1.60mmHg;t=-24.84,-18.90;both P＜0.01).The difference were 3.25±1.86,2.08±1.57mmHg respectively.Changes of CRF and CH were significantly different between two groups (t=-0.351,-1.081;both P＜0.01).CONCLUSION:The postoperative corneal biomechanics and lOP measurements are lower than preoperative.SMILE are lower than FS-lasik in changes of CRF,CH.
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<p><b>Background:</b>Localized macular edema and retinal nerve fiber layer (RNFL) thinning have been reported shortly after laser in situ keratomileusis (LASIK) in adults. However, it is still unclear how LASIK affects the retina of children. This study aimed to investigate the macular retina and RNFL thickness in children with refractive amblyopia who underwent femtosecond laser-assisted LASIK (FS-LASIK).</p><p><b>Methods:</b>In this study, we included 56 eyes of 32 patients with refractive amblyopia who underwent FS-LASIK in our hospital from January 2012 to December 2016. Foveal (foveal center retinal, parafoveal retinal, and perifoveal), macular inner retinal (superior and inferior), and peripapillary RNFL thicknesses (superior, inferior, temporal, and nasal) were measured using Fourier-domain optical coherence tomography before surgery and 1 day, 3 days, and 1 week after surgery. We divided these patients into three groups based on their refractive error: High myopic group with 22 eyes (equivalent sphere, >6.00 D), mild myopic group with 19 eyes (equivalent sphere, 0-6.00 D), and hyperopic group with 15 eyes (equivalent sphere, >+0.50 D). We compared the macular retina and RNFL thickness before and after LASIK. A paired simple t-test was used for data analysis.</p><p><b>Results:</b>One week after surgery, the visual acuity for all 56 eyes of the 32 patients reached their preoperative best-corrected vision. Visual acuity improved two lines or better for 31% of the patients. The residual refractive errors in 89% of the patients were within ±0.5 D. In the high myopic group, the foveal center retinal and parafoveal retinal thicknesses were thicker 1 day and 3 days after surgery than before surgery (t = 2.689, P = 0.012; t = 2.383, P = 0.018, respectively); no significant difference was found 1 week after surgery (P > 0.05). The foveal center retinal and parafoveal retinal thicknesses were greater 1 day after surgery than they were before surgery (P = 0.000 and P = 0.005, respectively) in the mild myopic and hyperopic groups. No significant difference was found 3 days or 1 week after surgery (P > 0.05). In all three groups, no significant difference was found in the macular inner retinal or peripapillary RNFL thickness 1 day, 3 days, or 1 week after surgery (P > 0.05).</p><p><b>Conclusions:</b>The foveal center retinal edema after FS-LASIK is mild and reversible in children, that mostly occurred in the high myopic group with no effect on the visual acuity, and is always relieved within 1 week.</p>
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The range of highly toxic Chinese medicinal materials was summarized according to the Appendix of Measures for the Management of Toxic Drugs and the records in Quality Standards of Chinese Medicinal Materials. As a result, there are 51 kinds of highly toxic Chinese medicinal materials in all. The significance of determining the list of highly toxic medicinal materials is as follows: providing reference to the amendments of the appendix of Measures for the Management of Toxic Drugs, to the management of highly toxic Chinese medicinal materials and promoting the safety of drug usage in our hospitals, and to the research of new traditional Chinese medicine containing highly toxic Chinese medicinal materials.
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On the base of the State Key-protected Wild Medicinal Species List, the State Key-protected Wild Animals List, the State Key-protected Wild Plants List (the first) and the Convention on International Tradein Endangered Species of Wild Fauna and Flora (CITES) Appendix I/II, and of the legal medicinal material standards, the range of nationalkey-protected wild medicinal materials is discussed in this article. It is suggested that 145 kinds of wild medicinal materials (160 kinds of species) should be put into the range of national key-protected wild medicinal materials. In addition, according to the State Key-protected Wild Plants List (the second, draft for discussion) and the legal medicinal material standards, there are about 35 kinds of wild medicinal materials (50 kinds of species) which could be taken into account as part of the range of national key-protected wild medicinal materials. Foregoing conclusion will be benefit to the Amendment of the State Key-protected Wild Medicinal Species List.
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The data of the alcohol concentration in alcohol precipitation process of 22 Chinese materia medica (CMM) were investigated and analyzed. The result showed that the real alcohol concentration in the alcohol precipitation process was higher than the expected generally, and the real alcohol concentration in the alcohol precipitation process in the same product was different in different batches. The gap between the real alcohol concentration in the alcohol precipitation process and the expected maybe related to the product and the method to determine how much alcohol to be added and the way of operation. The data above were analyzed, and some suggestions were presented as follows: (1) Meaning of the expected alcohol concentration in the alcohol precipitation process described in the drug quality specification should be explained clearly; (2) The method used to determine how much alcohol should be added and the indicator of on-line control should be studied and determined; (3) During the process validation, the real alcohol concentration in the alcohol precipitation process should be detected according to the procedure in China Pharmacopeia (2010 edition) and make sure whether the real alcohol concentration in the alcohol precipitation process was the same as the expected; (4) The alcohol precipitation process of new CMM should be systematically studied, and the method used to determine how much alcohol should be added must be on record in `Production Process for Oon-site Inspection'.
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As state key-protected wild medicinal materials, their species are collected in State Key-protected Wild Medicinal Species List, State Key-protected Wild Animals List, and State Key-protected Wild Plants List (the first) and Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) Appendix I/II, and there are legal medicinal material standards. Based on the statistical results of the existence frequency in Chinese patent medicine and the literatures of medicinal materials cultivation and breeding situation, the application of key-protected wild medicinal materials is preliminarily estimated, which would provide the reference for their sustainable utilization.
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Some laws about the national key-protected wild medicinal materials, their resources and application status are reviewed. Some problems about the management and application of the national key-protected wild medicinal materials are also analyzed. It is suggested that the special technical requirements should be put forward according to the endangered categories, the state, and requirement of resource. The registration of Chinese patent medicine containing the national key-protected wild medicinal materials should be confined strictly for their sustainable utilization.
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Background It is well known that the diminution of visual acuity appears before notable complications in some high myopic eyes.However,whether the impaired vision is associated with the change of retinal thickness at macula area is still under investigation.Objective This study was to investigate the relationship of macular retinal thickness with the change of visual acuity in high myopic eyes.Methods A consecutive caseobservational study was performed.Two hundred and forty-five eyes of 132 patients with the diopter of-6.00～-20.00 D were enrolled in this study during the January 2011 to January 2012 in Beijing Tongren Eye Center.All of the patients received the measurement of retinal thickness with Fourier Domain Optical Coherence Tomography (FDOCT),and the scan mode was MM6.The eyes were divided into the corrected vision ≥0.9 group and the corrected vision ≤0.8 group.In addition,the eyes were assigned to the non-posterior staphyloma group,posterior staphyloma Ⅰ group (macular symmetry) and posterior staphyloma Ⅱ group (macular gradient).The retinal thicknesses in different quadrants at the macular zone were measured and calculated by OCT software.Results The demography was matched in different groups.Corrected visual acuity was significantly increased in the corrected vision ≥ 0.9 group than that in the corrected vision ≤0.8 group (1.02±0.16 vs.0.62±0.08) (t=3.233,P=0.001).Retinal thickness value at fovea was (256.28±13.19) μm in the corrected vision ≥0.9 group,and that in the corrected vision ≤0.8 group was (231.17 ± 10.96) μm,with a significant difference between the two groups (t =2.134,P =0.031).The corrected visual acuity was 1.00±0.27,0.78±0.21 and 0.90±0.13 in the non-posterior staphyloma group,posterior staphyloma Ⅰ group and posterior staphyloma Ⅱ group,respectively,showing significant difference among the three groups (F=15.760,P=0.015),and the corrected visual acuity of the non-posterior staphyloma group and posterior staphyloma Ⅱ group were significantly higher than that of posterior staphyloma Ⅰ group (q =16.131,P =0.006 ; q =-10.831,P=0.008).A significant difference also was seen in the mean retinal thickness among the three groups (F=2.316,P =0.025).The mean retinal thickness in the posterior staphyloma Ⅰ group was (234.21 ± 15.69) μm,which was significantly smaller than (252.25± 15.31) μm of the posterior staphyloma Ⅱ group (q =12.977,P =0.023).There were no significant difference in the retinal thickness at para-fovea area among the three groups (F=0.318,P =0.078).However,significant difference was found at peri-fovea area in different groups (F=1.925,P =0.013).The mean retinal thicknesses at peri-fovea area was (273.26 ± 16.37) μm in the posterior staphyloma Ⅱ group and was significantly smaller than (289.11 ± 19.30) μm of the posterior staphyloma Ⅰ group and (290.33 ± 17.12) μm of the non-posterior staphyloma group (q =-8.305,P =0.023 ; q =-7.011,P =0.012).Conclusions The retinal thickness at fovea is associated with the corrected visual acuity in high myopic eyes.The thinning of retinal thickness at the vertex of posterior staphyloma is one of causes of visual function impairment.
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Background Keratectasia after laser in situ keratomileusis (LASIK) is one of the serious complications which affect the vision.The measurement of cornea posterior elevation is an important way helping to find this change.Objective The aim of this study was to investigate the change of cornea posterior elevation after LASIK in myopic eyes with astigmatism and affecting factors.Methods A series case-observational study was adopted.One hundred and twenty-seven myopic eyes with astigmatism of 66 patients who received LASIK in 2008 May through 2010 January in Beijing Tongren Hospital were retrospectively analyzed to evaluate the change of cornea posterior elevation following the LASIK.The parameters related to cornea posterior elevation were measured and compared before and 3 months,6 months and 1 year after surgery,respectively,with Oculyzer anterial segment analysis system.Results The height values from posterior cornea highest point,the lowest point and central vertex central elevation zone were (12.20±3.39),(-19.02±7.38) and (1.05 ±3.25) μm respectively before LASIK and were (14.38±3.80),(-18.55±7.11),(2.83±4.81)μm in3 months and (13.99±3.38),(-17.57±6.54),(2.45±4.61) μm in 6 months after LASIK.They were (14.40±3.85),(-17.76±6.00),(2.16±5.00) μm in 1 year after surgery.Significant increases were found in the vertex height and central elevation after LASIK compared with before surgery(highest pointq=6.813,5.594,6.875,all at P＜0.001.central vertex:q=4.488,P=0.002;q =3.530,P=0.013 ;q =2.799,P =0.047).However,no significant difference was seen in various time points after LASIK (P＞0.05).A positive correlation was obtained between the height value of the posterior cornea central vertex with the spherical equivalent (SE),maximum cutting depth or cutting proportion 1 year after LASIK (r =0.295,0.297,0.295,all at P=0.001),and there was a negative correlation between it with residual stroma (r=-0.208,P=0.019).The intraocular pressure (IOP) measured with noncontact tonometry (NCT) was (14.24±3.33) mmHg before LASIK,and those of 3 months,6 months and 1 year were (8.42± 1.90),(8.61 ± 1.64) and (8.76± 1.64)mmHg after LASIK,showing a significant lowing in IOP after LASIK in comparison with before LASIK (q =29.851,28.317,26.337,all at P＜0.001).But no significant change was found in the different time points after LASIK (P＞0.05).There was significant difference in the IOP corrected by Ehlers after LASIK (P＞0.05).The IOP before LASIK had positive correlation with the central elevation of posterior cornea surface 1 year after LASIK(r=0.258,P =0.003).Conclusions The cornea posterior elevation increases slightly early stage after LASIK but retains stable level with lapse of time.The refraction diopter before LASIK is the main factor affecting the posterior corneal shape.To reduce the risk of corneal ectasia,more attention should be paid to the reserving of appropriate corneal residual stroma and smallest degree of eccentricity during the ablation procedure.