The impact of accommodation function on the difference between noncycloplegic and cycloplegic refraction in adult myopes.

PURPOSE: To investigate the impact of accommodation function on the difference between cycloplegic and noncycloplegic subjective and automatic refraction in adult myopes. METHODS: Myopic patients between 18 and 50 years old evaluated at Peking University Third Hospital who underwent cycloplegic and noncycloplegic automatic and subjective refraction were enrolled. Accommodation function, including negative and positive relative accommodation (PRA/NRA) and accommodation response (binocular cross cylinder, BCC) was examined. RESULTS: Of the 3268 individuals enrolled, the mean age was 27.3 ± 6.9 years, and 34.8% of participants were male. The noncycloplegic spherical equivalent (SE) was 0.23 ± 0.29 D and 0.64 ± 0.61 D more myopic than cycloplegic subjective and automatic refraction. Adjusting for associated factors, participants with at least 0.50 D of more myopia SE refraction by noncycloplegic subjective refraction were more likely to be older (odds ratio [OR], 1.029; 95% confidence interval [CI], 1.013-1.045) and with insufficient (OR, 1.514; 95% CI, 1.093-2.096) and excessive (OR, 2.196; 95% CI, 1.538-3.137) NRA value. The automatic refraction SE difference of at least 1.00 D more myopia was more likely to be found in individuals with older age (OR, 1.036; 95% CI, 1.022-1.050) and accommodative lead (OR, 1.255; 95% CI, 1.004-1.568). CONCLUSION: A quarter of adult myopes had at least 0.50 and 1.00 D of subjective and automatic SE difference with cycloplegia. The accommodation function significantly affects the difference between cycloplegic and noncycloplegic refraction. Investigating the differences in refraction measurement guarantees the proper use of cycloplegia in adults for myopia correction.

Clinical comparison between brachytherapy of 0.5 ％ loteprednol etabonate eye drops and long-term therapy of 0.1％ fluorometholone eye drops after LASEK / 中华实验眼科杂志

Background Conventional corticosteroid therapy after laser epithelial keratomileusis (LASEK) is topical application of 0.1％ fluorometholone eye drops for 4 months,but this therapy increases the ocular hypertension risk and leads to poor compliance in patients.It is necessary to explore a safe and effective brachytherapeutic drug.Objective This study was to compare the clinical outcomes between the brachytherapy of 0.5％ loteprednol etabonate eye drops and the long-term therapy of 0.1％ fluorometholone eye drops after LASEK.Methods Clinical data were retrospectively analyzed from 208 right eyes in 208 mild and moderate myopia patients who received LASEK at Peking University Third Hospital from 2009 to 2013.The eye drops of 0.5％ loteprednol etabonate was used 6 times daily since operation day until postoperative day 5,and 4 times daily for a week,and then tapered for three consecutive weeks in 104 eyes of the loteprednol group after LASEK,and 0.1％ fluorometholone eye drops was applied topically 4 times daily for initial one month and then tapered for three consecutive months in another 104 eyes in the fluorometholone group after LASEK.Corneal epithelial healing time was compared between the two groups by recording the wearing duration of corneal contact lens.Noncontact intraocular pressure (lOP) was detected and corrected 5 days,2 weeks,1 month and 3,6 months after LASEK.Haze was scored based on the criteria of Cheng under the slit lamp microscope and apparently optometry was performed 1 month and 3,6 months after LASEK.Results The number of eyes removed corneal contact lens in 5,6 and 7 days after LASEK was not significantly different between the loteprednol group and the fluorometholone group (x2 =1.180,P =0.554).No considerable differences were seen in the eye numbers with the equivalent spherical lens (absolute value) ≤0.5 D in 1 month,3months and 6 months after LASEK (Z=-1.028,P=0.304;Z=-0.398,P=0.691;Z=-0.445,P=0.656).In the fifth days after surgery,the median corrected IOP was 13.52 mmHg and 13.12 mmHg in the loteprednol group and the fluorometholone group,respectively,showing a significant difference between them (Z =-1.985,P =0.047),but no significant differences were found in IOP in 2 weeks,1 month and 3 months,6 months after surgery between the two groups (all at P＞0.05).IOP elevated (postoperative IOP-preoperative IOP ≥ 5 mmHg) after LASEK in 5 eyes in the loteprednol group and 4 eyes in the fluorometholone group (x2 =0.116,P =0.733).In 1 month after surgery,the number of eyes in different grades of haze was significantly decreased in the loteprednol group compared with the fluorometholone group (x2=13.506,P=0.009),however,there was no significant differences in haze grading in postoperative 3 months and 6 months between the two groups (x2 =2.199,P =0.699;x2 =1.154,P =0.562).Conclusions Brachytherapy of 0.5％ loteprednol etabonate eye drops appears to have a similar effect in antiinflammation and inhibition of haze to the long-term therapy of 0.1％ fluorometholone eye drops after LASEK.Furthermore,topical application of 0.5％ loteprednol etabonate eye drops dose not increase the risk of ocular hypertension.

Thin flap is the tendency of laser in situ keratomileusis / 眼科

Up to date,excimer laser in situ kerratomileusis(LASIK) has being the main stream in the corneal refractive surgery.The main cause of iatrogenic kerateotasia and keratoconus is the failure of corneal biomechanics that is one of the most severe complications of LASIK.Thin flap will be the tendency of LASIK since it can preserve more under-flap stromal tissue to keep more intact corneal structure.With the femtosecond laser system that has advantages comparing with the mechanical microkeratome,we can customize the thin flap.There are some unique features in thin flap manipulation and post-operational healing process.The nomogram of the excimer laser and the post-OP medicine should be adjusted.

Scanning electron microscopy of corneal endothelial damage by Nd:YAG laser iridotomy and its repair / 眼科

Nd:YAG laser iridotomy was performed on 32 eyes of 20 Chinchilla rabbits and fol- lowed-up for 1-4 hours postoperatively to 8 months.Scanning electron microscopy show- ed that the corneal endothelium was dam- aged to various degrees by Nd:YAG laser iridotomy and the impaired areas healed up in 8 months through migration and prolifer- ation of the endothelial eclls.

Influence of disulfiram on the expression of transforming growth factor-?2 in form-deprived eyes in chicks / 北京大学学报(医学版)

Objective:To explore the temporal expression of retinal-choroidal transforming growth factor-?2(TGF-?2) in form-deprived myopia(FDM) chick eyes and study the effect of an inhibitor(disulfiram,DSF) of retinoid acid(RA) synthesis on refractive development and the expression of TGF-?2.Methods:Ninety new hatched white leghorn chicks were divided randomly and equally into 3 groups:unilateral occluded with frosted goggles(Group A);unilateral intravitreal injection of 4 mmol of the non-specific aldehydedehydrogenase inhibitor disulfiram with further treatment with goggles(Group B);unilateral intravitreal injections of 4 mmol of disulfiram without further treatment with goggles(Group C).Refraction and axial length were measured on 1,7 and 14 days after treatment.Expression levels of TGF-?2 and TGF-?2 mRNA in the retinal-choroid layer were analyzed by immunohistochemistry and real-time RT-PCR.Results:In Group A,the form-deprived eyes made by goggles developed myopia(P0.05) with TGF-?2 mRNA level growing on day 7 and decreased on day 14 in group B and decreased on day 1,increased on days 7 and 14 in Group C(P

Clinical study of higher order wavefront aberrations with a Tscherning aberrometer / 北京大学学报(医学版)

Objective: To study the higher order aberrations of emmetropic and ametropic eyes with wavefront aberrometer. Methods: Forty of cases 77 emmetropic and ametropic eyes were measured with an aberrometer based on Tscherning's principle with the pupils dilated. The Zernike coefficients and root mean square values of wavefront aberrations up to the 6th order were recorded and statistically analyzed. Results: The C06,C07,C08,C12,C13,C14,C24,C26,and C27 were significantly different from zero under 7 mm pupil size and the C06,C10,C12,C23,and C24 were significantly different from zero under 4 mm pupil size. There was no significant difference of higher order wavefront aberrations between emmetropic and ametropic eyes. Comparing the age of 40 years or less with the age over 40 years, there were significant differences in RMS3 between the two under 7 mm pupil size, and statistical diffenences in RMS6 and RMSh between the two under 4 mm pupil size. Conclusion: There are certain higher order wavefront aberrations in the normal human eyes, especially with the pupis dilated. No differences are found in higher order aberrations between emmetropic and ametropic eyes. The higher order aberrations of the age over 40 years are more than those of the age of 40 years or younger.

The role of the posterior corneal parameters measured by Pentacam in subclinical keratoconus screening / 眼科

Objective To estimate the role of the posterior corneal parameters measured by Pentacam in screening subclinical keratoconus.Design Retrospective case-controlled study.Participants Forty five healthy subjects(73 eyes),14 keratoconus patients (20 eyes),43 subclinical keratoconus patients(58 eyes).Methods Based TOPOLYZER and biomicroscope signs,eyes were diagnosed as subclinical keratoconus and keratoconus to compare the differnces of related posterior corneal parameters provided by Pentacam in normal eyes and subclinical keratoconus or keratoconus eyes.Main Outcome Measures Back-Diff(6 mm) max,Back-Diff(6 mm )min, Back-Difference(6 mm),Back-Rmin,Back-Astig.Results The parameters which were statistically different between normal corneas and clinical keratoconus,normal corneas and subclinical keratoconus include Back-Diff(6 mm)max(P

Comparison of laser in situ keratomileusis and laser-assisted subepithelial keratectomy for myopia more than-10.00 diopters / 北京大学学报(医学版)

0.05).There were more complaints of postoperative pain and discomfort after LASEK procedure.No severe vision threatening complications in these two groups were found.Conclusion:Both LASIK and LASEK are safe and effective in treating eyes with severe myopia.