Vector analysis of toric implantable collamer lens V4c implantation in correcting moderate to high myopia with high astigmatism / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate the clinical effect of toric implantable collamer lens(TICL)V4c for correcting moderate to high myopia with high astigmatism using vector analysis and quality of life impact of refractive correction(QIRC).METHODS: Retrospective case series. A total of 55 patients(90 eyes)with moderate to high myopia and high astigmatism who received TICL V4c implantation in the refraction surgery center of ophthalmology department in our hospital from January 2019 to December 2022 were collected. Followed-up for 1 a, the uncorrected distance visual acuity(UDVA), best corrected visual acuity(BCVA)and diopters were observed. Alpins vector analysis was used to evaluate the effect of astigmatism correction, and QIRC scale was used to evaluate patients' quality of life.RESULTS: At 1 a postoperatively, the UDVA of 98% eyes was the same or better than pre-operative BCVA, the safety index was 1.11±0.14, and the efficacy index was 1.11±0.15. The angle of error of 97% of the astigmatic eyes was within ±15°. The results of vector analysis showed that correction index was 0.83±0.13, angle of error was 1.00±4.49°, and index of success was 0.21±0.15. The total higher order aberrations under a pupil diameter of 6 mm was significantly increased compared with preoperatively(P<0.05), the QIRC score was significantly better than that before surgery(P<0.001), and the increase of total QIRC scores was positively correlated with preoperative spherical equivalent(rs=0.215, P<0.05), indicating that the higher degree of myopia before surgery the patients, the better the quality of life after TICL implantation.CONCLUSION: TICL V4c implantation for the correction of moderate to high myopia with high astigmatism is safe and effective, and the patients' quality of life significantly improved after surgery.

Clinical effect of cross positioning method for correcting low and moderate astigmatism during small incision lenticule extraction / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To evaluate the clinical outcomes of using the cross-positioning method for correcting low and moderate astigmatism during small incision lenticule extraction(SMILE)surgery with Alpins vector analysis.METHODS: A total of 50 patients(81 eyes)with low and moderate astigmatism with the rule ≤1.50 D who underwent SMILE surgery at the laser myopia treatment center of Xi'an No.1 Hospital from May 2022 to November 2022 were included in the prospective randomized controlled study, and they were divided into two groups according to the random table, with 25 case(41 eyes)in cross-positioning group and 25 cases(40 eyes)in control group. In the cross-positioning group, the patients' head position was adjusted based on the cross intersection lines before the standard SMILE procedure, aligning the lateral canthi with the horizontal line and the midpoint of the eyebrows and the nose bridge with the vertical line. Postoperative visual acuity and refractive results at 3 mo were observed in both groups, and astigmatic changes were analyzed and evaluated using the Alpins vector analysis method.RESULTS: During the follow-up period, 6 cases(11 eyes)in the cross-positioning group were lost to follow-up, while in the control group, 8 cases(14 eyes)were lost to follow-up, with 19 cases(30 eyes)and 17 cases(26 eyes)finally included in the cross-positioning group and the control group, respectively. At 3 mo postoperatively, the uncorrected visual acuity(UCVA)of both groups' operated eyes was ≥1.0, and no serious complications occurred, with no significant differences in UCVA, best corrected visual acuity(BCVA), spherical power, and spherical equivalent between the cross-positioning group and the control group(all P>0.05). The cylindrical power in the cross-positioning group was 0.00(0.00, 0.00)D, which was lower than -0.13(-0.50, 0.00)D in the control group(P=0.01). The vector analysis results showed that the difference vector(DV)in the cross-positioning group was lower than that in the control group [0.00(0.00, 0.00)vs 0.13(0.00, 0.50), P=0.01], and the index of success(IOS)was better than that of the control group [0.00(0.00, 0.00)vs 0.18(0.00, 0.77), P<0.01]. At 3 mo postoperatively, 26(87%)and 15(58%)eyes in the cross-positioning group and control groups achieved an angle of error(AE)within ±5°, respectively.CONCLUSION: The cross positioning method was used to calibrate the patients' head position during SMILE surgery, which reduced the axial position error and improved the accuracy of SMILE in correcting low and moderate astigmatism.

Comparison of surgically induced astigmatic changes after cataract surgery in post-Laser in situ keratomileusis corneas versus virgin eyes / Comparação de alterações astigmáticas induzidas cirurgicamente após cirurgia de catarata em córneas ceratomileusis in situ pós-Laser versus olhos virgens

ABSTRACT Purpose: Postoperative refraction in modern mi­croincision cataract surgery gained extra importance in patients with the previous laser-assisted in situ keratomileusis (LASIK) surgery. The surgically induced astigmatic changes in those eyes may differ not only in magnitude but also in direction compared to virgin corneas. This study aimed to compare the surgically induced astigmatic changes after microscopic cataract surgery between post-LASIK corneas and virgin eyes. Methods: Cases that underwent microincision cataract surgery in eyes with and without previous LASIK surgery were reviewed. The demographics, the axial length at cataract surgery, the central corneal thickness, spheric and cylindric values, keratometry readings, and postoperative posterior corneal astigmatism were retrospectively evaluated. A modified Alpins method was used for astigmatic vector analysis, and baseline astigmatism, surgically induced astigmatism, difference vector, flattening effect, and torque were assessed. Results: A total of 42 eyes from 24 subjects was evaluated. Group I consisted of 14 eyes with the previous LASIK, and Group II included 28 eyes without any refractive surgery. Preoperative mean central corneal thickness in Group I was significantly thinner (p=0.012). There was no significant difference in baseline astigmatism between the groups regarding magnitude and power vectors. After microincision cataract surgery, there were no significant differences in mean spheric and cylindric values and mean keratometry readings (all p>0.05). However, surgically induced astigmatism and difference vector were significantly higher on J45 vector component in post-LASIK eyes and microincision cataract surgery steepening effect on post-LASIK corneas was significantly higher than those in virgin eyes (p=0.001, p=0.002 and p=0.018, respectively). Conclusions: Cataract surgery has steepened the corneas in both groups with a significantly higher steepening effect in post-LASIK eyes. Certainly, corneal topography cataract surgery is particularly helpful to provide more precise surgically induced astigmatism interpretations.

RESUMO Objetivo: A refração pós-operatória na cirurgia mo­derna de catarata por microincisão ganha ainda mais importância em pacientes com cirurgia prévia de ceratomileuse in situ assistida por laser (LASIK). As alterações astigmáticas induzidas cirurgicamente nesses olhos podem diferir não apenas em magnitude, mas também em direção em comparação com córneas virgens. O objetivo deste estudo foi comparar as alterações astigmáticas induzidas cirurgicamente após cirurgia de catarata por microincisão entre córneas pós-LASIK e olhos virgens. Métodos: Foi revisada uma série de casos de cirurgia de catarata por microincisão em olhos com e sem cirurgia LASIK anterior. Os dados demográficos, o comprimento axial no momento da cirurgia de catarata, a espessura central da córnea, os valores esféricos e cilíndricos, as leituras da ceratometria e o astigmatismo corneano posterior pós-operatório foram avaliados retrospectivamente. O método Alpins modificado foi usado para análise vetorial astigmática e foram avaliados o astigmatismo basal, o astigmatismo induzido cirurgicamente, o vetor de diferença, o efeito de achatamento e o torque. Resultados: Ao todo, 42 olhos de 24 indivíduos foram avaliados. O Grupo I consistiu em 14 olhos com LASIK prévio; o Grupo II incluiu 28 olhos sem qualquer cirurgia refrativa. A média da espessura corneana central pré-operatória no Grupo I foi significativamente mais fina (p=0,012). Não houve diferença significativa no astigmatismo basal entre os grupos em termos de magnitude e vetores de potência. Após a cirurgia de catarata por microincisão, não houve diferenças significativas nos valores médios esféricos, cilíndricos e leituras médias de ceratometria (todos com p>0,05). No entanto, o astigmatismo induzido cirurgicamente e o vetor de diferença foram significativamente maiores no componente do vetor J45 em olhos pós-LASIK, e o efeito de aumento da inclinação pela cirurgia de catarata por microincisão nas córneas pós-LASIK foi significativo em comparação com olhos virgens (p=0,001, p=0,002 e p=0,018, respectivamente). Conclusões: A cirurgia de catarata aumentou a inclinação das córneas em ambos os grupos, sendo esse aumento significativamente maior nos olhos pós-LASIK. Certamente, a topografia da córnea antes da cirurgia de catarata é particularmente útil para fornecer interpretações mais precisas do astigmatismo induzido cirurgicamente.

Differences in refractive astigmatism, anterior corneal surface astigmatism and ocular residual astigmatism between dominant and non-dominant eyes in myopia / 中华实验眼科杂志

Objective:To investigate the differences in refractive astigmatism, the anterior corneal surface astigmatism and ocular residual astigmatism between dominant and non-dominant eyes in myopia.Methods:A corss-sectional study was conducted.Two hundred and seventy-six eyes from 138 patients with myopia who were to receive corneal refractive surgery in the Refractive Surgery Center of Tianjin Eye Hospital from January to March 2018 were included.Ocular dominance was assessed with the hole-in-the-card test.The manifest refraction and corneal topography were performed in order to measure the sphericity, spherical equivalent, the astigmatism of anterior corneal surface and total cornea.Vector analysis was used to calculate the value of the ocular residual astigmatism and the components of astigmatism, including J0 and J45 of both the refractive astigmatism and the astigmatism of anterior corneal surface.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Tianjin Eye Hospital (No.201909).Results:It was found that 61.6%(85/138) of the subjects was right-eye dominant.There was no significant difference in sphericity and spherical equivalent, J0 and J45 of the refractive astigmatism and the astigmatism of anterior corneal surface between dominant and non-dominant eyes (all at P>0.05). The magnitude of the ocular residual astigmatism of the dominant eye was 0.607(0.451, 0.808)D, which was lower than 0.701(0.497, 0.901)D of the non-dominant eye, showing a statistically significant difference ( Z=-2.52, P=0.01). Conclusions:In the myopic population with no significant difference in the sphericity and spherical equivalent between the dominant and non-dominant eyes, the magnitude of the ocular residual astigmatism of the dominant eye is significantly lower than that of the non-dominant eye, which may play an important role in the ocular dominance formation.

Vector analysis of astigmatic correction after single-step transepithelial photorefractive keratectomy and femtosecond-assisted laser in-situ keratomileusis for low to moderate myopic astigmatism

Purpose: This study aimed to evaluate the outcomes of astigmatic correction by single?step transepithelial photorefractive keratectomy (TransPRK) and femtosecond?assisted laser in?situ keratomileusis (Femto?LASIK) surgeries. Methods: A total of 218 subjects received TransPRK or Femto?LASIK surgery for the treatment of myopia and astigmatism (?2.25 to ?0.25 D). Refraction errors and uncorrected (UDVA) and corrected distance visual acuity (CDVA) were examined before and at 3 months after surgery. Astigmatism changes were assessed by vector analysis. Results: Preoperative parameters of the TransPRK group were similar to the Femto?LASIK group. UDVA and CDVA at 3 months were similar between both groups. Manifest refraction (MR) spherical equivalent in the TransPRK group (0 ± 0.20 D) was slightly lower compared with the Femto?LASIK group at 3 months (0.11 ± 0.25 D, P = 0.001). MR cylinder was ?0.06 ± 0.19 D in the TransPRK group and ?0.02 ± 0.15 D in the Femto?LASIK group at 3 months (P = 0.135). The index of success (IS) was 0.15 ± 0.36 in the TransPRK group and 0.06 ± 0.17 in the Femto?LASIK group (P = 0.125). The correction index (CI) was 1.03 ± 0.19 in the TransPRK group and 1.01 ± 0.11 in the Femto?LASIK group (P = 0.815). Conclusion: For low to moderate myopic astigmatism, TransPRK provided a comparable astigmatic treatment effect as Femto?LASIK. Myopic astigmatism was both slightly overcorrected after TransPRK and Femto?LASIK surgeries

Comparison of clinical outcome between femtosecond laser-assisted LASIK and SMILE for myopic astigmatism by vector analysis / 中华实验眼科杂志

Objective:To compare the accuracy and stability between corneal topography-guided femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) and small incision lenticule extraction (SMILE) for myopic astigmatism by vector analysis.Methods:A non-randomized controlled clinical trial was performed.One hundred and twenty patients (214 eyes) with myopic astigmatism who underwent the FS-LASIK or SMILE in Henan Eye Hospital from January 2020 to July 2020 were enrolled.The patients were divided into FS-LASIK group (58 cases, 105 eyes) and SMILE group (62 cases, 109 eyes) according to different surgeries.The visual acuity, refraction, intraocular pressure and corneal topography were examined before and 1 week, 1 month and 3 months after operation.The results of vector analysis between the two groups were compared, including target induced astigmatism vector (TIA), surgically induced astigmatism vector (SIA), magnitude of error (ME), angle of error (|AE|), difference vector (|DV|), correction index (CI), and index of success (IOS) 3 months after operation.This study protocol adhered to the Declaration of Helsinki and was approved by an Ethics Committee of Henan Eye Hospital (No.HNEECKY-2020[25]). Written informed consent was obtained from each patient before operation.Results:Three months after surgery, no astigmatism was found in 11 eyes (10.5%), and with the rule (WTR) astigmatism was in 23 eyes (21.9%), and against the rule (ATR) and oblique astigmatism were in 71 eyes (67.6%) in FS-LASIK group.In SMILE group, no astigmatism was detected in 35 eyes (32.1%), and WTR astigmatism was in 58 eyes (53.2%), and ATR and oblique astigmatism were in 16 eyes (14.7%), showing a statistically significant difference between them ( χ2 =48.20, P<0.05). The postoperative SIA, |AE|, |DV|, CI and IOS values in the SMILE group were lower than those in the FS-LASIK group, showing statistically significant differences between them (all at P<0.05). The ME was -0.20 (-0.37, 0.00)D in FS-LASIK group and 0.20 (0.00, 0.25)D in SMILE group.Within 3 months after operation, there was no significant difference in ME among different time points in the FS-LASIK group (all at P>0.05) and in spherical equivalent (SE) among different time points in the SMILE group (all at P>0.05). There was significant difference in the results of vector analysis among different time points in the two groups (all at P<0.05). Conclusions:Both FS-LASIK and SMILE are effective in the correction of myopic astigmatism.Astigmatism is slightly overcorrected by FS-LASIK and slightly undercorrected by SMILE.The axial error is smaller and the SE is more stable after SMILE within 3 months postoperatively.

Efficacy observation of Toric intraocular lens in correcting corneal astigmatism and vector analysis of residual astigmatism / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To observe the clinical effect of Toric intraocular lens(Toric IOL)implantation in the correction of corneal astigmatism, and vector analysis of residual astigmatism and corneal astigmatism.<p>METHODS: A retrospective case observation study. A total of 63 patients with 77 eyes who underwent phacoemulsification combined with Toric IOL implantation in our hospital from September 2018 to October 2019 were selected. LogMAR uncorrected distance visual acuity(UCDVA), best corrected distance visual acuity(BCDVA), residual astigmatism of subjective refraction were observed after operation in 1wk, 1mo, and 3mo. And after dilated pupil, the Toric IOL axis position was measured by OPD-scanⅢ, and compared with the target axis position(LAD).<p>RESULTS: The median(interquartile range)of UCDVA at 1wk, 1mo, and 3mo after operation were 0.22(0.15, 0.40), 0.30(0.15,0.40),and 0.30(0.15, 0.40), which were better than those of UCDVA \〖0.82(0.60, 1.22)\〗 and BCDVA \〖0.52(0.30, 0.70)\〗 before operation(<i>P</i><0.008). The residual astigmatism was 0.75(0.50, 1.00), 0.75(0.38, 1.00), 0.50(0.25, 1.00)D, respectively, which was significantly lower than that of preoperative corneal astigmatism \〖2.19(1.73, 2.69)D\〗(<i>P</i><0.008). At 3mo after surgery, the proportion of UCDVA(LogMAR)≤0.301 was 69%; the proportion of residual astigmatism ≤0.75D was 73%. The median LAD at 1wk, 1mo, and 3mo after surgery were 2.0°, 2.0°, and 3.0°; 81%, 82%, 77% were less than 5°. The maximum LAD value is 11°. Astigmatism vector analysis: preoperative corneal astigmatism was 2.31±0.80D, centroid value was 1.44D@177°±1.99D; Predicted postoperative residual astigmatism was 0.14±0.17D, centroid value was 0.02D@58°±0.22D; residual astigmatism at 3mo after operation was 0.69±0.53D, centroid value was 0.05D@142°±0.88D.<p>CONCLUSION: Toric IOL can effectively correct corneal astigmatism in patients with cataract and has good rotational stability. Astigmatism vector analysis can directly show the difference between predicting postoperative astigmatism and actual residual astigmatism, which is helpful to analyze and optimize the measurement of corneal astigmatism, calculation of IOL degree, surgical design, postoperative observation.

Clinical Outcomes of Small Incision Lenticule Extraction in Myopia: Study of Vector Parameters and Corneal Aberrations

Toric intraocular lens for correction of high corneal astigmatism in cataract patients / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To evaluate the efficacy of Bi-Flex toric intraocular lens ( T-IOL ) ( Medicontur, Medical Engineering, Ltd. ,Inc. ) implantation to correct preexisting astigmatism in patients having cataract surgery.? METHODS: This retrospective consecutive study included 22 eyes of 16 patients with more than 2. 50 diopters ( D ) of corneal preexisting astigmatism having cataract. Preoperative and postoperative uncorrected visual acuity ( UCVA ) , best corrected visual acuity ( BCVA ) , objective and subjective refraction and keratometric and topographic cylinder were measured. Postoperative the toric IOL axis was evaluated using vector analysis.? RESULTS: Postoperatively, subjective refractive cylinder was reduced significant ( P<0. 05 ) from 4. 05 ± 1. 53D to 1. 35 ± 0. 86D. The component J0 reduced in magnitude from -0.81±2.02D to -0.12±0.62D (P<0.05). Both, UCVA and BCVA improved significantly at 1mo after surgery (P<0. 05 in both cases). After the surgery, the UCVA and BCVA were 0. 24 ± 0. 19 and 0. 06 ± 0. 08, respectively. The mean toric IOL axis rotation was 2. 95 ± 5. 25 degree, with rotation less than 10 degrees in 86. 36％of eyes. No differences in mean keratometric values obtained before and after surgery were found (P>0. 05 for J0 and J45 ) .?CONCLUSION:Implantation of the Bi-Flex toric IOL is a safe and effective method to correct the preexisting regular astigmatism (greater than 2. 50D).

Applying vector analysis to evaluate influence of ocular residual astigmatism on astigmatism correction by FS-LASIK / 眼科新进展

Objective To investigate the influence of ocular residual astigmatism (ORA) on the correction of astigmatism by FS-LASIK with vector analysis.Methods The records of 182 patients who had accept FS-LASIK between January,2016 and April,2016 were retrosepectively reviewed.The patients whose ORA ≥ refractive cylinder were assigned to high ocular residual astigmatism group (HORA group),ORA ＜ refractive cylinder were assigned to low ocular residual astigmatism group (LORA group).All of the patients were followed 6 months or more.The visual acuity,error ratio and correction ratio were compared between HORA group and LORA group.Results The preoperative ORA of all patients was (0.61 ± 0.27) D,in which ＞ 0.75 D were 58 cases (31.9％),and the HORA group was more than the LORA group (P ＜ 0.05).At postoperative 6 months,there was no statistically significant difference in vision acuity between the HORA group (1.06 ± 0.15) and LORA group (1.08 ± 0.15) (t =0.97,P =0.35).There was statistically significant difference in the error ratio between the HORA group (58.11 ± 63.23) ％ and LORA group (26.12 ± 35.37) ％ (t =3.43,P ＜ 0.05).There was statistically significant difference in the correction ratio between the HORA group (146.45 ± 86.63) ％ and LORA group (122.56 ± 36.31) ％ (t =2.81,P ＜ 0.05).Conclusion The error ratio and correction ratio of astigmatic correction by FSLASIK is significantly higher in eyes with high ORA than in eyes with low ORA.Vector analysis should been carried out before the FS-LASIK.

Vector analysis and comprison of small incision lenticule extraction versus laser in-situ keratomileusis for low to moderate myopic astigmatism / 中华实验眼科杂志

Background Small incision lenticule extraction (SMILE) is lack of eye-tracking system and there is controversy in the treatment of astigmatism.It is very important to understand its correction effctiveness for myopic astigmatism.Objective This study was to evaluate the clinical outcomes in the correction of myopic astigmatism between SMILE and femtosecond laser assisted laser in situ keratomileusis (FS-LASIK).Methods In this retrospective study,95 eyes of 51 patients and 69 eyes of 40 patients with myopic astigmatism underwent the SMILE surgery and FS-LASIK surgery respectively in Tianjin Eye Hospital from December 2013 to July 2014 under the informed consent.No significant differences were found in spherical power,astigmatic power and spherical equivalent (SE) between the SMILE group and FS-LASIK group before surgery (all at P＞0.05).The uncorrected visual acuity (UCVA),best corrected visual acuity (BCVA),manifest refraction,slit-lamp microscopy,intraocular pressure and corneal topography were measured before surgery and 1 day,1 week,1 month,3 months after surgery.Vector analysis was used to calculate the components of astigmatism before and after surgery.Correction index (CI),index of success (IOS),angle of error (AofE) and flattening index (FI) were used to evaluate the correction effectiveness of astigmatism.Safety index and efficacy index were used to evaluate the recovery status of visual acuity.The corrected effectiveness was compared between the two groups,and the correlations of kappa angle with measured parameter were assessed by Spearman rank correlation analysis.Results The mean spherical power,astigmatic power and SE were (0.003±0.106),(-0.063 ± 0.126) and (-0.029 ± 0.101) D in the SMILE group,which were significantly lower than (0.112 ± 0.212),(-0.091 ± 0.142) and (0.067 ± 0.198)D in the FS-LASIK group (Z =-4.328,-3.197,both at P＜0.05).Vector analysis showed the postoperative with-the-rule astigmatism in the SMILE group and oblique astigmatism in the FS-LASIK group respectively,and the CI and F1 in the SMILE group were significantly lower than those in the FS-LASIK group (Z =-3.051,-3.126,both at P ＜ 0.05).The insignificant reduce in IOS and AofE were seen in the SMILE group compared with the FS-LASIK group (Z=-1.557,P=0.119;Z =-1.923,P =0.054).In addition,the safety index and efficacy index were not significantly different between the two groups (both at P ＞ 0.05).Negative correlations were found between safety index or efficacy index and preoperative kappa angle in the SMILE group (r =-0.258,-0.257,both at P＜0.05).Conclusions Both SMILE and FS-LASIK surgeries are effective and safe in correcting myopic astigmatism with good postoperative visual acuity.SMILE surgery shows less axis rotation and higher accuracy than FS-LASIK because of small incision and flapless procedure.The correction of cylinder can adjust based on experience of surgeon.

Effect of Toric Intraocular Lens Implantation on Astigmatism in Cataract Surgery

PURPOSE: To evaluate the efficacy of Tecnis(R) toric intraocular lens (IOL) implantation for the correction of astigmatism and rotational stability during cataract surgery in patients with cataract and astigmatism. METHODS: We prospectively analyzed 17 eyes of 14 patients with 1 to 4 diopters (D) of corneal astigmatism who underwent phacoemulsification and Tecnis(R) toric IOL implantation at Seoul National University Hospital from June 2013 to May 2014. Informed consent was obtained from all participants before the clinical trial. We evaluated the changes in visual acuity, refraction, astigmatism, IOL axis and higher order aberration for 3 months postoperatively. Power vector analysis was used to analyze astigmatism. RESULTS: The mean uncorrected visual acuity (log MAR) significantly improved from 0.58 +/- 0.34 to 0.26 +/- 0.43 at 3 months postoperatively. The mean refractive astigmatism was significantly decreased by 77.9% from a mean value of -2.67 +/- 0.89 D to -0.59 +/- 0.48 D at 3 months postoperatively. According to power vector analysis, M, B, J0, and J45 were significantly reduced after the surgery. The mean difference between achieved and intended IOL axis was 3.26 degrees clockwise at postoperative 3 months, which was statistically insignificant. Most of the rotational changes were observed within a month after the surgery. CONCLUSIONS: Phacoemulsification and Tecnis(R) toric IOL implantation in patients with cataracts and astigmatism showed efficacy for the correction of astigmatism and rotational stability.

Long term clinical outcome of cataract patients with Toric intraocular lens implantation / 中华实验眼科杂志

Background Epidemiological investigation showed that 15％-29％ of patients with cataract have preexisting astigmatism of ＞ 1.50 D.So to control astigmatism is very important to the improvement of visual function after cataract surgery.The implantation of Toric intraocular lens (IOL) is a new option for the correction of preexisting astigmatism during cataract surgery,now.Short-term clinical studies of cataract patients with AcrySof Toric IOL implantation have revealed a good stability.However,the evaluation of long-term clinical result is seldom.Objective This study was to evaluate the long-term clinical results of Toric intraocular lens(IOL) implantation.Methods A serial case-observational study was designed.One hundred and twenty eyes of 78 cataract patients were included in this study.Phacoemulsification combined with AcrySof Toric IOL implantation was performed and the patients received a 2-year follow-up.Uncorrected distance visual acuity (UCDVA),best corrected distance visual acuity(BCDVA),residual cylinder,IOL rotation,vector analysis and accuracy of astigmatic correction were clinically evaluated in 1 day,1 month,3 months,6 months,1 year and 2 years,respectively.Comparison of these results of different follow-up periods were made.Results Sixty-seven patients (101 eyes)finished the follow-up and 19patients(19 eyes)lost visit due to other diseases affected.At 2 years visit after AcrySof SN60TT implantation,UCDVA,BCDVA,residual cylinder,absolute value of IOL rotation degree,vector magnitude of surgically induced astigmatism (SIA) was 0.16 (0.20),0 (0.1),0.75 (0.5) D,(2.9± 1.8) °,(1.2 ± 0.6) D,and the correction index (CI)was 0.90±0.41.A positive correlation was found between SIA and TIA(r=0.74,P =0.000).Compared to 1 month,3,6 months and 1 year,there was a mild tendency of decrease in accuracy of astigmatism correction and CI.Residual cylinder and degree of IOL rotation at 2 years after surgery were also slightly higher.However these changes were not statistically significant (P＞0.05).Conclusions After 2 years of follow-up,patients with AcrySof Toric implantation remain good visual acuity.AcrySof Toric IOL presents excellent long-term rotational stability and accuracy of astigmatism correction.

Comparisons of Corneal Topographic Change Between 20-Gauge and 23-Gauge Pars Plana Vitrectomy

PURPOSE: To compare the changes in corneal topography between 23 gauge (G) pars plana vitrectomy (PPV) and 20 G PPV. METHODS: Forty-three eyes of 42 patients who underwent PPV were divided into 2 groups: 20G PPV (Group I, n=18) and 23 G PPV (Group II, n=25). Both groups were followed up over 3 months postoperatively. ORBSCAN II was performed to compare the corneal topographic change of 20 G PPV and 23 G PPV. RESULTS: In a 5 mm zone, significant postoperative change in the mean corneal surface cylinder was found between the 1st day and the 1st month in Group I, while no significant change was found in Group II. Postoperatively, the increase in the mean corneal surface cylinder in Group I was significantly higher than in Group II between the 1st day and the 1st month. Clinically significant astigmatism, induced by surgery, was found only in Group I one week after the operation. In a 3 mm zone, there was no significant change in the mean corneal surface cylinder in both groups postoperatively. The difference in the mean corneal surface cylinder between the 2 groups at the postoperative periods showed no significant change. Surgically induced astigmatism was significantly higher in Group I than in Group II between the 1st day and the 1st month postoperatively. CONCLUSIONS: PPV with the 23 G system is a sutureless transconjunctival surgery, which appears to be more effective due to insignificant corneal surface and astigmatic changes in the early postoperative period.

Power Vector and Aberrations Using Corneal Topographer and Wavefront Aberrometer Before and After Pterygium Surgery

PURPOSE: To determine the power vector and aberrations before and after surgery for pterygium using a corneal topographer and a wavefront aberrometer. METHODS: The study group consisted of 34 eyes of 31 patients with pterygium, and were divided into two groups by pterygium size ( or = 3 mm, group II). Power vector and wavefront aberrations were evaluated using a corneal topographer (Oculus inc., Germany) and a wavefront aberrometer (LADARWAVE(R), Hartmann shack aberrometer, Alcon inc., US) at pre- and postoperative 1 week, 1 month, and 3 months. RESULTS: The preoperative blurring strength (B) and high order aberrations significantly decreased at postoperative 3 months in all groups (P or = 3 mm). To reduce aberrations and astigmatism effectively, we suggested surgical intervention in eyes with pterygia sized < 3.0 mm.

Changes in Astigmatism after Surgical Repair of Epiblepharon or Ptosis: A Vectorial-analytic Approach

PURPOSE: To analyze the changes of astigmatism and keratometric cylinder by using the scalar and vector analysis method in children who had undergone surgery for epiblepharon or ptosis. METHODS: The study subjects were 142 eyes of 79 patients who had undergone surgery for epiblepharon or ptosis. We examined the cycloplegic refractive error and keratometric astigmatism by auto-refractometry before and 2 months after surgery. Astigmatic changes were analyzed through the scalar and vector analysis method. RESULTS: The mean age of the patients was 5.27+/-2.18 years of age, and the male to female ratio was 35: 44. There were 98 eyes of 49 patients in the epiblepharon surgery group, 28 eyes of 22 patients in the ptosis surgery group, and 16 eyes of 8 patients in the epiblepharon and ptosis surgery (combined surgery) group. The epiblepharon surgery group demonstrated a decrease in with-the-rule astigmatism, and the changes in magnitude (p<0.001) and vector (p<0.05) of keratometric cylinder were statistically significant. The ptosis surgery group demonstrated an increase in with-the-rule astigmatism and the changes in magnitude and vector of astigmatism were statistically significant (both p<0.01). The combined surgery group demonstrated an increase in with-the-rule astigmatism and the changes in vector of astigmatism and magnitude of keratometric cylinder were statistically significant (both p<0.05). CONCLUSIONS: Our results showed significant astigmatic change in eyes that underwent surgery for epiblepharon or ptosis. Therefore, careful cycloplegic refraction is necessary after epiblepharon or ptosis surgery.

Surgically Induced Astigmatic Change after Laser in Situ Keratomileusis using Manual Microkeratome

We performed spherical LASIK operations using manual microkeratome and assessed the axis and magnitude of surgically induced astigmatism by vector analysis[Jaffe's rectangular coordinates]. Six month follow-up of 124eyes of 98 patients who were followed for 6 months or longer were included. Myopia ranged from -4.00 to -9.75 diopter. We divided eyes depending on the degree of myopia;group 1, 31 eyes between -4.00 and -5.75 diopter, group 2, 46 eyes between -6.00 and -7 .75 diopter, and group 3, 47 eyes between -8.00 and -9.75 diopter. Also, we compared the axis of surgically induced astigmatism between right eyes[73 eyes]and left eyes[48 eyes]. Preoperative astigmatic refraction was -0.63 +/-0.30 diopter in group 1, -0.67 +/-0.35 diopter in group 2, -0.67 +/-0.41 diopter in group 3.After 2 months, magnitude of surgically induced astigmatism was 0.84 +/-0.57 diopter in group 1, 1.08 +/-0.72 diopter in group 2, 1.19 +/-0.84 diopter in group 3[P=0.15], after 6 months, 1.01 +/-0.59 diopter in group 1, 1.16 +/-0.98 diopter in group 2, and 0.99 +/-0.59 diopter in group 3[P=0.52]. Change in the axis of vectorial-induced astigmatism was not statistically significant between right eyes and left eyes after 2 months[P=0.16], but significant after 6 months[p<0.05 ]. In conclusion, spherical LASIK using manual microkeratome may induce a significant change in magnitude of the astigmatism regardless the degree of myopia. The difference of astigmatic axis was statistically significant between right eyes and left eyes after 6 months. These changes and differences may require long-term follow-up and further investigation.

Practical electrocardiographic interpretation

In summary, electrocardiographic interpretation is anchored on the objective reading of the ECG without the advantage of seeing and/or knowing the patient when the electrocardiographer is isolated in the heart station. When the electrocardiographer is the attending physician, the advantage of knowing the patient may create a favorable bias in the interpretation, leading to a clearer understanding of the ECG and correct diagnosisSeparating the normal from the abnormal tracing is of primary concern to any electrocardiographer. Sorting out the types of abnormalities is the second step. Done this way, the ECG becomes an important diagnostic tool in providing excellent cardiac care delivery.

Clinical Result of Excimer Laser Photoastigmatic Refractive Keratectomy Using VISX 20/20 B VisionKeyTM with Version 4.01 Software

Photoastigmatic refractive keratectomy (PARK) using VISX 20/20 B excimer laser with version 4.01 software was performed in 205 consecutive eyes of compound myopic astigmatism to assess the efficacy, predictability, and safety of excimer laser treatment of compound myopic astigmatism between September 1994 and June 1996. The mean preoperative manifest spherical equivalent refraction was -6.95+/-2.52D (range -1.13 to -15D) and the mean preoperative manifest cylindrical refraction was -1.25+/-0.76D (range -0.5 to -4.50D). The patients were followed from 6 months to 1 year (mean 9.19 months). At 1 year, 82(75.2%) of all 109 eyes receiving PARK were within 1D of plano refraction, and 88(80.7%) of all 109 eyes achieved uncorrected visual acuity of 20/30 or better. Postoperative refractions were stable after 3 months without significant early overcorrection. Mean postoperative astigmatism was -0.29+/-0.40D at 6 months and -0.24+/-0.42D at 12 months. Overall improvement of astigmatism was 75% at 6 months and 82% at 12 months by vector analysis using Alpins` method. In conclusion, PARK using VISX 20/20 B VisionKeyTM excimer laser with version 4.01 software appears to be effective in the treatment of compound myopic astigmatism with a relatively high degree of accuracy and safety. The predictability and stability of the postoperative refraction during the first 12 months seem to be quite reliable.

Clinical Evaluation of IOGEL 1103Lens Implantation

We studied the postoperative results of 38 patients (40 eyes) who received the implantation of IOGEL 1103 (Alcon, U.S.A.), a single piece intracapsular fixing hydrogel lens. Scleral pocket incision was done tangentially 2mm posterior to the surgical limbus and 4mm in length. The diameter of continuous curvilinear capsulorhexis (GCC) was about 5mm and intercapsular phacoemulsification was carried out. No suture or single 10-0 nylon suture was used for the closure. Uncorrected visual acuity of 20/40 or better was observed in 70% of all cases at 1 week postoperatively and in 90% at 2 months postoperatively Mean keratometric astigmatism analized by vector analysis was 0.65 diopter (D) at 1 week postoperatively and -0.13D at 8 weeks postoperatively and the changes from preoperative astigmatism was 0.31D at 1 week postoperatively, and 0.43D at 8 weeks postoperatively. Intraocular lens (IOL) was damaged during insertion into the capsular bag in 7.5%. Fibrinoid membrane on IOL surface formed in 5% and cystoid macular edema was shown in 2.5%. Severe shrinkage of anterior capsule (less than 3 mm in diameter) was shown in 22.5% at 8 weeks postoperatively. Early postoperative results revealed that IOGEL 1103 is relatively stable in the capsular bag and induces good visual recovery with less astigmatism. However, a method to prevent the postoperative shrinkage of anterior capsule and a proper shape of hydrogel lens should be investigated in the future.