Meta-analysis of the effect and safety of Cyclopentolate and Atropine on ciliary muscle paralysis in myopic children / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To systematically evaluate the effect and safety of cyclopentolate and atropine on ciliary muscle paralysis before optometry in myopic children. <p>METHODS: Relevant references published before April 2020, which concerned about cyclopentolate compared with atropine for ciliary muscle palsy in children with myopia, were obtained by searching PubMed, EMBASE, Web of Science, The Cochrane Library, CNKI and WanFang Database. For the selected studies, after data extraction and methodological quality evaluation of the included study, RevMan5.3 software was used for Meta-analysis. <p>RESULTS: Nine articles were finally included, containing 588 eyes using atropine and 592 eyes using cyclopentolate. Meta-analysis results indicated: comparing of cyclopentolate and atropine for cycloplegia in children with myopia before optometry, the diopter difference between the two is <i>WMD</i>: -0.01, 95%<i>CI</i>(-0.30, 0.27), <i>P</i>=0.93; the difference in residual accommodation power between the two is <i>WMD</i>: 0.22, 95%<i>CI</i>(-0.13, 0.58), <i>P</i>=0.22. In addition, the cyclopentolate is safer and has a lower incidence of adverse reactions.<p>CONCLUSION: Compared with atropine, cyclopentolate has equivalent effects on ciliary muscle paralysis in myopic children, and has higher security. Cyclopentolate could replace atropine for myopic children before optometry.

Availability of Cycloplegic Refraction in Children and Adolescents

PURPOSE: To compare non-cycloplegic and cycloplegic refractive errors and evaluate the utility of cycloplegia in Korean children and young adolescents.METHODS: An anterospective study including 406 outpatients was conducted from September 2015 to December 2017. Pre and post-cycloplegic refractive errors for both eyes were measured using Ocucyclo® and Mydrin P® with an auto-refractor. Patients were divided into different groups according to age: group 1 (< 4 years), group 2 (4–6 years), group 3 (6–8 years), group 4 (8–10 years) and group 5 (< 20 years).RESULTS: A total of 203 patients were studied. Standard deviation (sphere post-pre) was 1.26 ± 1.02 diopters significant in all age groups (p < 0.05). The mean difference decreased with increasing age (r = 0.207, p < 0.05), however, 9% of group with age greater than 10 years old still had manifest refraction-cycloplegic refraction (MR-CR) difference greater than 2 diopters. There were no significant cylindrical or axial component value difference before and after cycloplegia (p = 0.071). Significantly greater MR-CR differences were observed in hypermetropes ≥ 6 years old and myopes ≤8 years old (p < 0.05). The prevalence of pre-cycloplegic eyes with anisometria was 22.6% and 32.6%, a total of 7.39% regressed after cycloplegia (p > 0.05).CONCLUSIONS: After CR hyperopic shift was observed in all age groups. In patients with age greater than 10 years old, although statistically not significant, anisometropia and pseudomyopia still existed. Thus cycloplegic refraction should be performed in young adolescent to precisely measure and correct refractive error and avoid overcorrection.

Variant myopia: A new presentation?

Purpose: Variant myopia (VM) presents as a discrepancy of >1 diopter (D) between subjective and objective refraction, without the presence of any accommodative dysfunction. The purpose of this study is to create a clinical profile of VM. Methods: Fourteen eyes of 12 VM patients who had a discrepancy of >1D between retinoscopy and subjective acceptance under both cycloplegic and noncycloplegic conditions were included in the study. Fourteen eyes of 14 age- and refractive error-matched participants served as controls. Potential participants underwent a comprehensive orthoptic examination followed by retinoscopy (Ret), closed-field autorefractor (CA), subjective acceptance (SA), choroidal and retinal thickness, ocular biometry, and higher order spherical aberrations measurements. Results: In the VM eyes, a statistically and clinically significant difference was noted between the Ret and CA and Ret and SA under both cycloplegic and noncycloplegic conditions (multivariate repeated measures analysis of variance, P < 0.0001). A statistically significant difference was observed between the VM eyes, non-VM eyes, and controls for choroidal thickness in all the quadrants (Univariate ANOVA P < 0.05). The VM eyes had thinner choroids (197.21 � 13.04 ?) compared to the non-VM eyes (249.25 � 53.70 ?) and refractive error-matched controls (264.62 � 12.53 ?). No statistically significant differences between groups in root mean square of total higher order aberrations and spherical aberration were observed. Conclusion: Accommodative etiology does not play a role in the refractive discrepancy seen in individuals with the variant myopic presentation. These individuals have thinner choroids in the eye with variant myopic presentation compared to the fellow eyes and controls. Hypotheses and clinical implications of variant myopia are discussed.

Evaluation of cycloplegic effectiveness of atropine, cyclopentolate and tropicamide / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM:To investigate the effectiveness of three cycloplegia drugs: atropine, cyclopentolate and tropicamide on school-age children, and provid theoretical basis in choosing cycloplegic drugs for school-age children. <p>METHODS: Totally 420 myopic school-age students(818 eyes)in out-patients department were selected during July to August 2017. Candidates were divided into three medicine groups according to their age: Group A: <8 years old, utilizing 1% atropine; Group B: 8-12 years old, utilizing the cyclopentolate; Group C: >12 years old, utilizing the tropicamide. The difference of refraction degree before and after medicine application were calculated. <p>RESULTS: The coincidence rate of spherical equivalent refraction with cycloplegia and without cycloplegia was 81.0% in atropine group, 81.3% in cyclopentolate group and 79.4% in tropicamide group respectively. There was statistical difference of refraction results of the Group A between with atropine cycloplegia and without cycloplegia. The mean difference was -0.113±0.226D(<i>t</i>=-4.663, <i>P</i><0.001). There was no statistical refraction difference of the Group B between with cyclopentolate cycloplegia and without cycloplegia, the mean difference was -0.025±0.192D(<i>t</i>=-1.665, <i>P</i>=0.099). So does the difference of Group C between with tropicamide cycloplegia and without cycloplegia, which was -0.026±0.193D(<i>t</i>=1.760, <i>P</i>=0.080). <p>CONCLUSION: For children older than 8-years old and without strabismus and amblyopia, cyclopentolate or tropicamide can be used to give cycloplegia refraction for the first time, which is convenient for their daily activities. The cycloplegia refraction results should been re-checked after used atropine, and giving prescription by using the principle of maximum plus to maximum visual acuity(MPMVA).

Cycloplegic Refraction in Hyperopic Children: Effectiveness of a 0.5% Tropicamide and 0.5% Phenylephrine Addition to 1% Cyclopentolate Regimen

PURPOSE: To evaluate the effectiveness of a cycloplegic regimen using 0.5% tropicamide and 0.5% phenylephrine (Tropherine, Hanmi Pharm), in addition to 1% cyclopentolate, in hyperopic children. METHODS: The medical records of hyperopic patients below the age of 14 years who had undergone cycloplegic retinoscopy were retrospectively reviewed. Cycloplegic refractions were performed using one of two cycloplegic regimens. Regimen 1 was a Tropherine-added regimen comprising the administration of one drop of 1% cyclopentolate followed by two to three drops of Tropherine added at 15-minute intervals. Regimen 2 was a cyclopentolate-only regimen comprising the administration of three to four drops of 1% cyclopentolate at 15-minute intervals. The mean difference between noncycloplegic and cycloplegic refraction was compared between the two regimens. RESULTS: A total of 308 eyes of 308 hyperopic children were included. The mean difference (±standard deviation) in the spherical equivalent (SE) between cycloplegic and noncycloplegic refraction was significantly larger in regimen 2 than in regimen 1, with values of +1.70 ± 1.03 diopters (D) and +1.25 ± 0.89 D, respectively (p=0.001). The SE change after cycloplegia was significantly different between the two regimens only in patients aged 5 years or younger (p=0.001), particularly in those with high hyperopia with an SE ≥5 D (p=0.005) or fully accommodative esotropia (p=0.009). There was no significant difference between the two regimens in patients older than 5 years, regardless of the presence of high hyperopia or fully accommodative esotropia. CONCLUSIONS: The Tropherine-added regimen exerted a weaker cycloplegic effect than the cyclopentolate-only regimen, particularly in children under the age of 5 years with high hyperopia or fully accommodative esotropia. However, the difference in refraction between the two regimens was small. A Tropherine-added regimen can be effective in hyperopic children, with less associated discomfort than the instillation of cyclopentolate.

Comparison of Manifest Refraction and Cycloplegic Refraction Using Retinoscopy or an Autorefractor in Children

PURPOSE: To compare the measurements between manifest refraction and cycloplegic refraction using retinoscopy or an autorefractor in children and to investigate factors affecting the difference. METHODS: A total of 388 children with a mean age of 7.4 ± 3.6 years were examined using retinoscopy and a Grand Seiko GR-3500KA autorefractor before and after cycloplegia. We compared the difference in spherical and cylindrical components between refractions and analyzed the results according to gender, age, type of refractive error, amblyopia, strabismus, and neuro-developmental disorder. A difference in refractions of ±0.50 D or more was considered as a significant discrepancy. RESULTS: Before cycloplegia, the spherical portion of the refractive error via autorefractor measurement was more myopic than for the retinoscopic measurement in 47.2% of patients, and the cylindrical portion was greater in 37.1%. The spherical discrepancies were more common in children aged < 7 years, with hyperopia, or amblyopia (respectively, p = 0.002, p < 0.001, and p = 0.033). After cycloplegia, the spherical component of the refractive error by auto-refraction differed from retinoscopic measurement in 29.4% of patients, and the cylindrical portion differed in 30.7%. However, the difference was not significant and there was no difference according to clinical features. More than half of the children with discrepancies in the spherical component between retinoscopic refractions before and after cycloplegia had a discrepancy between auto-refraction and retinoscopic refraction before cycloplegia, and the two discrepancies had a significant correlation. CONCLUSIONS: Auto-refraction after cycloplegia can estimate retinoscopic values partially. Nevertheless, 30% of the children still showed a discrepancy. The discrepancy of manifest refraction or auto-refraction compared to retinoscopic refraction with cycloplegia should be considered in younger children, cases with hyperopia or amblyopia, and cases with a difference in auto-refraction and retinoscopic refraction before cycloplegia.

Transient Myopic Shift Due to Increased Latent Accommodation after LASEK

PURPOSE: To investigate accommodation and progress of patients who showed myopia on manifest refraction in the early postoperative period after LASEK. METHODS: Forty-one eyes were included in the present study which had undergone LASEK surgery from February to March 2012. Seven eyes showed myopia over -0.25 D on manifest refraction at 1 month postoperatively, but showed decreased amount of myopia at 2 months postoperatively and were classified as group 1. The other 34 eyes were classified as group 2. The differences between cycloplegic and manifest refraction (CRSE-MRSE) were defined as the amount of latent accommodation and compared between the 2 groups. RESULTS: Amount of latent accommodation was 0.179 +/- 0.426 D in group 1 (7 eyes), 0.265 +/- 0.303 D in group 2 (34 eyes) preoperatively, 1.286 +/- 0.664 D in group 1, 0.368 +/- 0.536 D in group 2 at 1 month postoperatively, and 0.500 +/- 0.520 D in group 1, and 0.489 +/- 0.546 D in group 2 at 2 months postoperatively. The amount of latent accommodation in group 1 was significantly greater than that of group 2 one month postoperatively. As the amount of latent accommodation decreased, the amount of myopic shift decreased gradually over 2 months in group 1 after surgery. CONCLUSIONS: Transient myopic shift due to increased latent accommodation was observed in several patients one month postoperatively and the amount of myopic shift decreased with time without treatment. Thus, surgeons should consider cycloplegic refraction when planning treatment for patients with myopic regression.

Side Effects after the Use of Cyclopentolate for Cycloplegic Refraction

PURPOSE: To investigate the frequency of side effects due to the use of cyclopentolate for cycloplegic refraction. METHODS: For 4 months, temperature change and adverse effects in 157 children who visited the pediatric ophthalmology clinic of a university hospital for cycloplegic refraction using cyclopentolate were observed. Topical 1% cyclopentolate was instilled 5 times at 5 minute intervals and temperature measured before and after administration using a tympanic thermometer. Side effects such as facial flushing, skin rash, and central nervous system disorders were recorded while cycloplegic refraction was performed. RESULTS: The mean temperature was increased 36.67 +/- 0.10degrees C to 36.90 +/- 0.09degrees C, but no fever exceeded 38degrees C. Seventeen (10.83%) patients experienced side effects including facial flushes (n = 6), temperature change (n = 5), abnormal central nervous system symptoms (n = 4), and a visible skin rash (n = 2). No patient experienced more than 1 side effect and long term adverse effects were not observed. CONCLUSIONS: The incidence of side effects due to cyclopentolate instillation for cycloplegic refraction was 10.83% in children. Although side effects due to cyclopentolate disappeared without any treatment, cafeful monitoring for their occurrence is necessary.

Reliability and Usefulness of Refractive Measurements by PlusoptiX S09 in Children

PURPOSE: To compare the refractive measurements obtained using a photorefractor (PlusoptiX S09, PlusoptiX GmbH, Germany) with those obtained using cycloplegic refraction in children. METHODS: We assessed the refractive status of 268 eyes in 134 children. The values acquired via photorefraction with a PlusoptiX S09 device were compared with those obtained by cycloplegic retinoscopy. Hyperopia (> or =+3.5 D), myopia (> or =-3.0 D), with the rule or against the rule astigmatism (> or =-1.5 D), and oblique astigmatism (> or =-1.0 D) were set as diagnostic criteria for refractive amblyopia risk factors (RARFs). The difference in the detection of RARFs by the two methods was the main outcome measure. RESULTS: The average spherical refractive power was -0.81 +/- 1.68 D for PlusoptiX S09 versus -0.26 +/- 2.00 D for cycloplegic retinoscopy (average difference -0.54 +/- 0.61 D; p < 0.001). The average spherical equivalent was -1.20 +/- 1.62 D for PlusoptiX S09 versus -0.64 +/- 1.94 D for cycloplegic retinoscopy (average difference -0.56 +/- 0.62 D; p < 0.001). The average cylinder power was -0.79 +/- 0.93 D for PlusoptiX S09 versus -0.76 +/- 0.94 D for cycloplegic retinoscopy (average difference -0.03 +/- 0.33 D; p = 0.135). Even though cycloplegic retinoscopy is considered the gold standard, the sensitivity and specificity for detecting RARFs with the PlusoptiX S09 were 88.0% and 96.3%, respectively. CONCLUSIONS: PlusoptiX S09 is a relatively useful method for detecting RARFs, but the device tends toward myopic shift compared to cycloplegic refraction, and hyperopia is underestimated.

Optimal dosage of cyclopentolate 1% for cycloplegic refraction in hypermetropes with brown irides.

To find the optimal dosage of cyclopentolate 1% for cycloplegic refraction in hypermetropes with brown irides, we investigated the difference in cycloplegic auto-refractions obtained after one, two, and three instillations in the same patient. The mean hypermetropia found after three instillations was statistically significantly more compared to that found after one instillation. There was no statistically significant difference in the mean hypermetropia between two and three instillations. There was no significant effect of gender, age, and the presence and type of horizontal deviation. These observations suggest that two drops of cyclopentolate 1% 10 min apart are sufficient for cycloplegic refraction in hypermetropes.

A Case Report on the Change of the Refractive Power After a Blunt Trauma

PURPOSE: To determine the pathogenesis of transient myopia after blunt eye trauma. METHODS: In one patient, the refraction of both eyes (the left eye was injured, but the right eye was not) was measured with an autorefractometer. The cycloplegic refraction was measured at the early stage of trauma and again 3 months after the blunt eye injury. The angle and depth of the anterior chamber, the ciliary body, and the choroids were examined by ultrasound biomicroscopy (UBM) over 3 months. The depth of the anterior chamber, the thickness of the lens, and the axial length were measured by A-scan ultrasonography in both eyes. During the 3 months after the injury, we made comparisons between the menifest and the cycloplegic refractions, the depths of anterior chambers, the thickness of the lenses, the axial lengths, and the UBM-determined appearances of the angles and depths of the anterior chambers, the ciliary bodies, and the choroids in both eyes. RESULTS: We suspect that the depth reduction in the anterior chamber, the increase in anterior to posterior lens diameter, and the edema in the ciliary body are all related to the change in the refractive power following the blunt trauma. CONCLUSIONS: Ultrasound biomicroscopy (UBM) and ultrasonography of the anterior segment in the eye may be helpful to diagnose and confirm changes in the refractive power that occur after trauma.

A Case Report on the Change of the Refractive Power After a Blunt Trauma

PURPOSE: To determine the pathogenesis of transient myopia after blunt eye trauma. METHODS: In one patient, the refraction of both eyes (the left eye was injured, but the right eye was not) was measured with an autorefractometer. The cycloplegic refraction was measured at the early stage of trauma and again 3 months after the blunt eye injury. The angle and depth of the anterior chamber, the ciliary body, and the choroids were examined by ultrasound biomicroscopy (UBM) over 3 months. The depth of the anterior chamber, the thickness of the lens, and the axial length were measured by A-scan ultrasonography in both eyes. During the 3 months after the injury, we made comparisons between the menifest and the cycloplegic refractions, the depths of anterior chambers, the thickness of the lenses, the axial lengths, and the UBM-determined appearances of the angles and depths of the anterior chambers, the ciliary bodies, and the choroids in both eyes. RESULTS: We suspect that the depth reduction in the anterior chamber, the increase in anterior to posterior lens diameter, and the edema in the ciliary body are all related to the change in the refractive power following the blunt trauma. CONCLUSIONS: Ultrasound biomicroscopy (UBM) and ultrasonography of the anterior segment in the eye may be helpful to diagnose and confirm changes in the refractive power that occur after trauma.

Comparison with Cycloplegic Refraction after Single-dose At ropinization and Three-day At ropinization at Esotropic Children

We compared cycloplegic refraction after convenient, less toxic single-dose atropinization with conventional three-day atropinization in esotropic children. We examined sixty children below eight years of age with esotropia. Their eyes were examined by cycloplegic refraction at 90 and 120 minutes after administering a drop of atropine twice at five minutes interval. After eight applications for three days, we performed cycloplegic refraction of their eyes. In the two groups, spherical equivalent and spherical power were statistically significantly different, and it had no statistical significance between the measurement of single-dose atropinization plus 0.5 diopter and three-day atropinization. The side effects were found lesser in single-dose application than conventional three-day applications. The results showed that single-dose atropinization can be substituted for conventional three-day atropinization in clinical practice.

Comparison of Refractive Errors Measured by Several Different Methods

PURPOSE: Preoperative measurement of refractive error before LASIK or PRK is very important for good postoperative result because the measured refractive error is the basis of correction amount of operation. We analyzed the difference in spherical equivalent values of manifest refraction by operator (OMR), manifest and cycloplegic refraction by resident (RMR and RCR), noncycloplegic automated refraction (AMR). METHODS: The randomized charts of 50 patients (100 eyes) who had undergone LASIK or PRK for myopia at the Department of Ophthalmology at Samsung Medical Center between May 2000 and November 2000 were reviewed retrospectively and spherical equivalent values of preoperative OMR, RMR, RCR, and AMR by Nikon NRK-8000 autorefractor were analyzed by paired T-test. RESULTS: The mean spherical equivalent values of OMR, RMR, RCR, AMR were -5.40+/-2.10 D, -5.47+/-2.23 D, -5.36+/-2.18 D, -6.25+/-2.24 D, respectively. The spherical equivalent value of AMR was more myopic than the values of others and the bias was statistically significant. The absolute difference of spherical equivalent diopter between OMR and RMR was 0.27+/-0.27 D and that between OMR and RCR was 0.30+/-0.33 D. These two absolute difference did not show statistical significance. CONCLUSIONS: This study revealed that there was statistically significant difference in spherical equivalent diopter measured by AMR compared to those measured by OMR, RMR, or RCR. So we recommend the method of manifest and cycloplegic refraction by two ophthalmologists before LASIK or PRK for accurate measurement of refractive error.

The Utility of Hand Held Autorefractometer for Refraction in Children

We studied the utility of hand held autorefractometer on the cycloplegic refraction for poor coorperated children by analyzing the data taken from hand held autorefractometer(Retinomax) and Canon R-10 autorefractometer. Seventy patients(140 eyes) were studied. We divided them into two groups according to the age: Group I included patients less than 4 years, Group II over 4 years. There were no statistic significant differences in the spherical and cylindrical values regardless of age and cooperability in cases of less than 6 diopter but statistic significant difference in cases of high refractive errors (>6 diopter) or cylindrical axis values. In Conclusion, this study revealed that hand held autorefractometer was useful for checking refraction of the poor coorperated children and the spherical and cylindrical values of Retinomax have no differences from the values of R-10 in the cases of less than 6 diopter.

The Effectiveness of Photorefraction for the Screening of Amblyogenic Factors

It is the purpose of this study to evaluate the effectiveness of MTI photoscreener(using the eccentric photorefraction principle) by comparing the sensitivity and specificity between the refractive errors determined by MTI photoscreener and cycloplegic refraction in 5 to 6 year-old children in the kindergartens. Pass/fail screening data was determined by the two masked observers, and compared with the results of cycloplegic refraction. And, the statistical analysis was done. There was some differences in the sensitivity rate between the two examiners. Two cases of anisometropia and one media opacity were found by the two observers, respectively. The sensitivity rate was 70%, specificity rate 90%, overall correlation rate 87%, positive predictive value 52% and negative predictive value 95% in the combined results by the observer A and B. The results of our study suggest that MTI photoscreener may be a reliable mass-screening method of detecting amblyogenic factors(refractive error, etc) in the preschool children although the sensitivity rate is slightly variable.

Changes in Refractive Error Following Strabismus Surgery

To investigate the changes in refractive error following strabismus surgery, we stratified a total of 32 exotropic patients; 11 patients with horizontal recess/resect procedure in one eye; 11 patients with lateral rectus recession in one eye; and 10 patients with medial rectus resection in one eye. The cycloplegic refraction and corneal topography were examined prospectively in each group. We found a significant decrease in the refractive power at 180degrees meridian resulting in with the rule astigmatism in lateral rectus muscle recess group (p<0.05) and a significant decrease in the refractive power at 90degrees meridian resulting in against the rule astigmatism in medial rectus resection group in the first week after surgery (p<0.05). However, there was no statistically significant change due to mixture of the two procedures in recess/resect group. The changes in refractive power in four months after surgery gradually recovered to preoperative state in each group except 90degrees meridian in medial rectus resection group. These results indicate that the changes in refractive error in one week after strabismus surgery involved steepening of 180degrees meridian in medial rectus resection group, and flattening of 180degrees meridian in lateral rectus muscle recession group. However, there was no statistically significant change due to mixture of the two procedures in recess/resect group.

Change of refraction in premature infants after cryotherapy for retinopathy of prematurity between the age of six months and three years

To investigate the chronological change of refraction in premature infants after cryotherapy for retinopathy of prematurity (ROP), cycloplegic refractions had been performed at 6 months and 3 years after term in premature infants who underwent cryotherapy for ROP. The changes of refractions between the two study ages were evaluated not only in the total cryo-treated eyes, but also in the subdivided groups according to the posterior pole appearances. In the total 61 eyes of 32 premature infants, mean spherical equivalents were -4.05D vs. -5.94D (6 months vs. 3 years) (p = 0.0001). In the normal posterior pole group (48 eyes), mean spherical equivalents were -3.45D vs. -5.68D (6 months vs. 3 years) (p = 0.0000), and in the abnormal posterior pole group (13 eyes), -6.28D vs. -6.86D (6 months vs. 3 years) (p = 0.6496). These results mean that there is a myopic progressive change between 6 months and 3 years after term in the cryo-treated eyes for acute ROP and it is more evident in the eyes with normal posterior pole.

The Changes of Refractive Error and Corneal Astigmatism after Horizontal Strabismus Surgery

We performed a prospective study of evaluating preoperative and postoperative refractive error and corneal curvature in cycloplegic refraction and keratometry in 25 eyes of 25 patients undergoing horizontal recession and resection procedure. At 4 months after operation, the change of refractive error by cycloplegic refraction was +0.12D in average in horizontal meridian, which was a significant shift toward 'with-the-rule astigmatism' direction(p0.05). In horizontal meridian, the with-the-rule astigmatic changes of +0.5D or more were present in 7 eyes(28%) and the against-the-rule astigmatic changes of -0.5D or more were present only in 2 eyes(8%). In vertical meridian, we found that 3 eyes(12%) had the changes of +0.5D or more and 6 eyes(24%) had the changes of -0.5D or more. The change of corneal curvature in keratometry amounted to average -0.50D in horizontal meridian(that means the flattening of cornea)(p0.05) at postoperative 4 months, showing the results similar to those of cycloplegic refraction. Futhermore, the astigmatic change by cycloplegic refraction and keratometry at postoperative 2 weeks and 1 month were similar to those at postoperative 4 months. These data suggest that there may be significant changes in astigmatism(more commonly in with-the-rule astigmatism) after strabismus surgery, and this astigmatic change appears due to the corneal change resulting from the variation in the force that the muscles exert on the globe.

Myopia in Premature Infants

The authors performed cycloplegic refraction in premature infants at the 6 months and 3 years of age to evaluate the incidence and degree of myopia and the changes of refractive errors according to the development, disease course and cryotherapy of retinopathy of prematurity (ROP). In 180 eyes of 99 infants at the 6 months of age, the incidences of myopia were not different between eyes with no ROP and eyes with spontaneously regressed ROP (36.3%, 25.5%), and the degrees of myopia were low in both groups (-1.76D, - 2.25D). In eyes with regressed ROP after cryotherapy, the incidence of myopia was high (75.5%) but the degree of myopia low (-3.0:3D). In eyes with cicatrical ROP, cryotreated or not, both of the incidence and the degree of myopia were high(93.9%, -5.50D). It is suggested that the incidence of myopia is increased after cryotherapy but the degree of myopia occurring after cryotherapy is low. In eyes with spontaneously regressed ROP, the degrees of refractive errors did not change from 6 months to 3 years of age, whereas in eyes cryotreated or with cicatrical ROP, the degrees of refractive errors were progressively changed to myopic side.