The exact etiology and pathogenesis of myopia are not known yet, although various studies of the development of myopia in experimental animals have been made. Authors attemtped whether rabbits developed axial myopia by fusing their lids at birth in one eye, or not. The monocular vision was deprived by suture of upper and lower lids in 12 rabbits which were 5 day-old. The other eye was unsutured as the control. Ten months later, we assessed refractive error, corneal curvature, axial length, and intraocular pressure and enucleation was done. We observed the histologic change of sclera with light microscope. The eyes with lid suture were more myopic(-3.35 +/- 0.99D) than the controlled eyes(-0.21 +/- 0.46D) (p<0.01). The corneal curvature and intraocular pressure were not significantly different between two groups. The axial lengths of the sutured eves were increased(21.27 +/- 1.70mm) in comparison with those of the controlled(17.39 +/- 1.83mm)(p<0.01). We conclude the difference in axial length was caused by the elongation of the posterior segment of eyeball. since lens thickness, depth of anterior chamber, and corneal curvature were identical in both groups. These were correlated with histologic change that showed thinner posterior parts of sclera of the sutured eyes than those of the controlled eyes. The results of this study demonstrate that monocular lid fusion in rabbits produced an expenmental axial myopia.
Animals ; Anterior Chamber ; Eyelids* ; Intraocular Pressure ; Myopia* ; Parturition ; Rabbits* ; Refractive Errors ; Sclera ; Sutures* ; Vision, Monocular

To investigate the relationship between peripheral retinal degeneration and axial length, we conducted a clinical study on 254 subjectives (508 eyes) whose age lie between 19-25 years and who had no other ocular disease nor any previous eye surgery. Axial length was measured with A-scan ultrasonography and retinal periphery was inspected by 360 degrees biomicroscopic examination with Goldmann three-mirror lens. The recorded degenerative peripheral retinal lesions were; lattice degeneration, pigmentary degeneration, cystoid degeneration, white without pressure, retinal hole or tears, retinal detachment, posterior vitreous detachment. The statistical analysis was done by using the chi-square test. The mean axial length was 24.01 +/- 1.08mm with a range of 21.8 to 27.9mm. The overall prevalence of the peripheral retinal degenerations increased as axial length did. Specially, that of pigmentary, cystoid, lattice degeneration was significantly related with long axial length individually for each lesion(p<0.01). However, there was a significantly greater percentage(53.37%) of all lesions in 23.0 - 24.9mm axial length group. These results suggest that the frequency of peripheral retinal degeneration increased with axial length but there was a posibility that the peripheral retinal degenerative lesions can be found in eyes of the mean and the shorter axial length.
Prevalence ; Retinal Degeneration* ; Retinal Perforations ; Retinaldehyde* ; Ultrasonography ; Vitreous Detachment

We retrospectively evaluated the 130 low vision patients on the basis of medical recordings. Men(58.5%) were more than women. The patients in teen-age(11-20yr) were most common(23.9%). Etiologies were aphakia due to congenital cataract(21.5%), macular degeneration(15.4%), and optic atrophy(13.8%) in that order. Low vision aids were prescribed for rehabilitation of the low vision. High-power plus glasses(25.4%), magnifiers(24.6%), and telemicroscope(7.9%) were low vision aids commonly prescribed for near vision, while hand-held telescope(23.8%) was the most popular for distance vision aids. High-power plus glasses were actually worn by 31 of 32 patients prescribed for them.
Aphakia ; Eyeglasses ; Female ; Glass ; Humans ; Medical Records ; Rehabilitation ; Retrospective Studies ; Vision, Low*

Albinism is a hereditary disease caused by the defect of tyrosinase that converts tyrosine to dihydroxyphenylalanine (DOPA). `Oculocutaneous albinism' is classified as hypopigmentation of skin, hair and eyes, but incidences of `ocular albinism' where hypopigmentation is limited to eyes are found rarely. Biochemically, albinism is caused by the tyrosinase activity. Typical findings in oculocutaneous albinism include not only ophthalmologic problems such as hypopigmentation of skin, foveal hypoplasia, photophobia and decreased visual acuity but also congenital nystagmus. We cannot determine distinctive characteristics of nystagmus of albinism because domestically, there are only a few reports that have been recorded correctly about nystagmus of albinism. Merely, we present our experience of two cases of albinism with congenital nystagmus because we think that these two cases, showing different types of nystagmus and electronystagmography, stand for the two representative types of nystagmus found in the literature up to date.
Albinism ; Albinism, Oculocutaneous* ; Dihydroxyphenylalanine ; Electronystagmography ; Genetic Diseases, Inborn ; Hair ; Hypopigmentation ; Incidence ; Monophenol Monooxygenase ; Nystagmus, Congenital* ; Photophobia ; Skin ; Tyrosine ; Visual Acuity

PURPOSE: The purpose of this study is to compare the postoperative results of surgery for 60 patients with intermittent exotropia (20-30PD). METHODS: They were classified into two groups: one group with bilateral lateral rectus recession (n=34) and another group with unilateral medial rectus resection and lateral rectus recession (n=26). We assessed the postoperative results by comparing the deviation at postoperative 1 year to those at 1day, 1week, 1month, and 6months after surgery. RESULTS: The stisfactory result defined as orthophoria and deviation between 10PD esodeviation and 10PD exodeviation. The postoperative success rates are as follows: 65% in the bilateral rectus recession group and 62% in the unilateral lateral rectus muscle recession and medial rectus resection group. In the bilateral lateral rectus recession group, postoperative 1 day alignment of 11-15PD esodeviation showed the success rate of 83%. In the unilateral medial rectus resection and lateral rectus recession group, postoperative 1 day alignment of 1-5PD esodeviation resulted in the success rate of 80%. CONCLUSIONS: The initial postoperative esodevation of 11-15PD in bilateral lateral rectus recession and esodeviation of 1-5PD in unilateral medial rectus resection and lateral rectus recession can lead to good results. Postoperative 1 year surgical results for exotropia of moderate degree could be predicted from angle of deviation at postoperative 6 months, regardless of the type of surgery.
Esotropia ; Exotropia* ; Humans

PURPOSE: To determine the amount of additional surgery required for patients with consecutive esotropia, who had an esodeviation angle similar to their pre-operative exodeviation angle, following bilateral lateral rectus recession surgery for intermittent exotropia. METHODS: The medical records of 29 patients who underwent surgery for intermittent exotropia from 1998 through 2013 were reviewed. These patients had consecutive esotropia with an unchanged postoperative esodeviation angle. Thirteen patients underwent esotropia surgery with the aim of full correction (Group A), while 16 patients underwent esotropia surgery with the aim of partial correction (Group B). The postoperative ocular alignment and stereopsis of both groups were compared. RESULTS: A total of 29 patients were evaluated including 13 patients in Group A and 16 patients in Group B. At the final follow-up visit, at least 24 months post procedure, Group B had a significantly greater success rate than Group A (62.5% vs. 23.1%, p = 0.039). Over-correction rates were higher in Group A than Group B (76.9% vs. 37.5%, p = 0.039). The changes during the follow-up period (6 months to their last follow-up) showed that the over-correction rate had increased from 30.8% to 76.9% in Group A (p = 0.034) and from 12.5% to 37.5% in Group B (p = 0.046). CONCLUSIONS: Consecutive esotropia surgery with the aim of partial correction showed favorable motor and sensory outcomes in patients who had a postoperative esodeviation angle similar to that of their pre-operative exodeviation. This strategy may also be helpful in preventing long-term postoperative over-correction in patients presenting with consecutive esotropia.
Depth Perception ; Esotropia ; Exotropia ; Follow-Up Studies ; Humans ; Medical Records

Recently refractive corneal surgery has been increasing and intraocular lens implantation is a routine procedure during cataract surgery. Many people have various activities in the evening such as night driving, thus it may be very important measuring the pupil size in the dark in determining the size of the optical zone. We measured pupil size of sixty normal adult candidates in darkness of 0, 20, 60, 100 lux and also in the bright illumination of 200 lux for comparison using near lens camera and slide film. The pupils became larger with younger age and increased darkness. Pupil Size(log mm) = 4.57 - 0.0388 X Age(year) - 0.005 X Luminance(lux). The average pupil size of all age groups were 7.0mm, 6.56mm, 5.97mm, 5.4mm sequencially in darkness and 4.77mm in brightness(200 lux). The average pupil size of 20~30 year old group who are socially active even at night was 7.18mm and 8.4mm in maximum. This has significant meaning clinically. Additionally the size of pupil became larger with increased corneal diameter and the amount of anisocoria tended to be greater with the increase of the darkness.
Adult* ; Anisocoria ; Cataract ; Darkness ; Humans ; Lens Implantation, Intraocular ; Lighting ; Pupil*

PURPOSE: To investigate whether combining inferior oblique weakening procedures with bilateral lateral rectus recession as a surgical approach to intermittent exotropia enhances postoperative horizontal angle of deviation over bilateral lateral rectus recession alone. METHODS: Patients were allocated to one of two surgical groups: a bilateral lateral rectus recession group (Group 1) or a bilateral lateral rectus recession with bilateral inferior oblique weakening group (Group 2). Group differences in the angle of distance deviation were evaluated preoperatively and at 3- and 12-months postoperatively. RESULTS: There were no significant differences in preoperative factors or angles of deviation between Group 1 (n = 98) and Group 2 (n = 77); no significant intergroup difference in the angle of deviation was observed at any postoperative time point (p > 0.05). CONCLUSIONS: Combined inferior oblique weakening procedures did not significantly influence the horizontal angle of deviation after surgery for intermittent exotropia. Accordingly, there is no need to revise the surgical amount of lateral rectus recession.
Exotropia* ; Humans

The visual system of newborn infants is not like that of adults. Both ocular and neural structures essential for vision will undergo anatomical and physiological changes as maturation process. The maturation of all visual systems occurs relatively rapidly in normal children. So, early examination of visual acuity is critical for normal visual funciton achievement. Visual acuity in preverbal children can be assessed using several techniques, such as fixation and following behavior under both monocular and binocular conditions, the optokinetic nystagmus technique, preferential looking, visual evoked potential, and recognition acuity using a vision chart. Most clinicians consider the standard technique of recognition acuity to be the gold standard for visual acuity assessments, 20/20 vision should be achieved by 7 years of age. Significant refractive error, a high degree of hyperopia, myopia, or astigmatism may result in not only blurred vision, but also strabismus and amblyopia. Therefore, early vision screening is very valuable. Subjective and objective refractive techniques are standard for detecting significant refractive errors in children and are available under either non-cycloplegic or cycloplegic conditions. Amblyopia is the most common cause of vision loss in children and young adults, defining as a reduction of best-corrected visual acuity due to the interruption of normal visual development during the so-called sensitive period. If the problem is not identified until the sensitive period is complete, the vision loss is permanent. Visual impairment in childhood affects all aspects of the child's development. Earlier treatment is associated with better outcomes. Of course, patient compliance and parental support are the most important factors contributing to treatment success.
Adult ; Amblyopia ; Astigmatism ; Child ; Evoked Potentials, Visual ; Humans ; Hyperopia ; Infant, Newborn ; Myopia ; Nystagmus, Optokinetic ; Parents ; Patient Compliance ; Refractive Errors ; Strabismus ; Telescopes ; Vision Disorders ; Vision Screening ; Visual Acuity* ; Young Adult

The visual system of newborn infants is not like that of adults. Both ocular and neural structures essential for vision will undergo anatomical and physiological changes as maturation process. The maturation of all visual systems occurs relatively rapidly in normal children. So, early examination of visual acuity is critical for normal visual funciton achievement. Visual acuity in preverbal children can be assessed using several techniques, such as fixation and following behavior under both monocular and binocular conditions, the optokinetic nystagmus technique, preferential looking, visual evoked potential, and recognition acuity using a vision chart. Most clinicians consider the standard technique of recognition acuity to be the gold standard for visual acuity assessments, 20/20 vision should be achieved by 7 years of age. Significant refractive error, a high degree of hyperopia, myopia, or astigmatism may result in not only blurred vision, but also strabismus and amblyopia. Therefore, early vision screening is very valuable. Subjective and objective refractive techniques are standard for detecting significant refractive errors in children and are available under either non-cycloplegic or cycloplegic conditions. Amblyopia is the most common cause of vision loss in children and young adults, defining as a reduction of best-corrected visual acuity due to the interruption of normal visual development during the so-called sensitive period. If the problem is not identified until the sensitive period is complete, the vision loss is permanent. Visual impairment in childhood affects all aspects of the child's development. Earlier treatment is associated with better outcomes. Of course, patient compliance and parental support are the most important factors contributing to treatment success.
Adult ; Amblyopia ; Astigmatism ; Child ; Evoked Potentials, Visual ; Humans ; Hyperopia ; Infant, Newborn ; Myopia ; Nystagmus, Optokinetic ; Parents ; Patient Compliance ; Refractive Errors ; Strabismus ; Telescopes ; Vision Disorders ; Vision Screening ; Visual Acuity* ; Young Adult