Long-term development of significant visual field defects in highly myopic eyes.

PURPOSE: To identify the characteristics that are associated significantly with visual field (VF) defects in highly myopic eyes. DESIGN: Retrospective, observational series. METHODS: The medical records of 492 eyes of 308 patients with high myopia (myopic refractive error > 8 diopters or axial length ≥ 26.5 mm) with a follow-up of 5 years or more were reviewed. The VFs were determined by Goldmann kinetic perimetry, and the VFs were quantified in 100 sectors within the V4 isopter. Eyes with loss of 10% or more of the sectors were classified as having significant VF defects, and a further loss of 10% or more during the follow-up period was classified as a significant progression. To avoid the influence of the posterior fundus changes resulting from the high myopia, eyes with any type of myopic macular or peripheral lesions that could cause visual field defects were excluded. RESULTS: Significant VF defects were newly developed in 13.2% of these selected highly myopic eyes during a mean follow-up ± standard deviation of 11.6 ± 5.5 years. The incidence of significant VF defects in myopic eyes was significantly higher in eyes with an oval optic disc than that in eyes with a round optic disc. An oval optic disc was present significantly more frequently in the myopic eyes with VF defects. Temporal and nasal VF defects were present in the same eye. Among the eyes with significant VF defect, the temporal VF defects were observed in 61.5% of the eyes with round discs, in 75.0% of the eyes with vertically oval discs, and in 68.2% of the eyes with obliquely oval discs. During a mean follow-up ± standard deviation of 10.2 ± 3.4 years, 73.8% of the eyes showed a significant progression of the VF defects. An abrupt change of the scleral curvature (types VII and IX staphyloma by Curtin) was the only factor significantly associated with a progression of the VF defects. CONCLUSIONS: Because the VF defects are progressive, we suggest that high myopia is a high risk factor for VF defects and that these eyes be examined at least once yearly. The combination of stretching and distortion of the optic nerve fibers resulting from an abrupt change of scleral curvature may be the factors that lead to the damage of the optic nerve fibers in highly myopic eyes.

Long-term changes in axial length in adult eyes with pathologic myopia.

OBJECTIVE: To examine the long-term changes of the axial length in adults with high myopia. DESIGN: Open-label, consecutive, retrospective case series. METHODS: The medical records of 101 patients (184 eyes) with high myopia (myopia ≥-6 diopters or axial length ≥26.5 mm) were studied. The axial length of the eye was measured by A-scan ultrasonography. The significance of the changes in the axial length during follow-up was determined. The effects of the age, axial length, and the presence of a posterior staphyloma at the initial examination on the axial length elongation were determined. RESULTS: The mean follow-up period was 8.2 years. The median axial length increased significantly from 28.6 mm at the initial examination to 29.4 mm at the final examination in the 184 eyes. The axial length remained stable (≤1-mm difference) in 69%, whereas the axial length increased by more than 1 mm in 31% of the eyes. For these 31%, the median axial length increased by 1.55 mm. An increase of the axial length per year was significantly greater in older patients than their younger cohorts, and the increase in eyes with a posterior staphyloma was significantly greater than in eyes without a staphyloma. Multiple regression analyses showed that the axial length elongation was positively and significantly correlated with patient age at the initial examination. CONCLUSIONS: In highly myopic adult patients, the axial length continued to increase. Older individuals with posterior staphyloma were more susceptible to having a larger increase in the axial length. A progression of posterior staphyloma with increasing age is considered a key factor for the continuous increase of axial length in adults with high myopia.

Long-term pattern of progression of myopic maculopathy: a natural history study.

OBJECTIVE: To investigate the long-term progression pattern of myopic maculopathy and to determine the visual prognosis of each progression stage. DESIGN: Retrospective, observational case series. PARTICIPANTS: The medical records of 806 eyes of 429 consecutive patients with high myopia (refractive error more than -8.00 diopters [D] or axial length > or =26.5 mm) who were followed for 5-32 years were reviewed. METHODS: Participants had complete ophthalmological examinations including best-corrected visual acuity, axial length measurements, fluorescein angiography, and color fundus photography, at least once a year. The presence and type of posterior staphyloma was determined by binocular stereoscopic ophthalmoscopy. The types of myopic maculopathy included tessellated fundus, lacquer cracks, diffuse chorioretinal atrophy, patchy chorioretinal atrophy, choroidal neovascularization (CNV), and macular atrophy. None of the patients had received any type of treatment for the maculopathy. MAIN OUTCOME MEASURES: The longitudinal long-term progression pattern and the visual prognosis of each type of fundus lesion. RESULTS: During the mean follow-up of 12.7 years, 327 of the 806 highly myopic eyes (40.6%) showed a progression of the myopic maculopathy. The most commonly observed patterns were from tessellated fundus to the development of diffuse atrophy and lacquer cracks, an increase in the width and progression to patchy atrophy in eyes with lacquer cracks, an enlargement of the diffuse atrophy, and the development of patchy atrophy in eyes with diffuse atrophy, and an enlargement and fusion of patches of atrophic areas in eyes with patchy atrophy. Eyes with tessellated fundus, lacquer cracks, diffuse atrophy and patchy atrophy at the initial examination progressed to the development of CNV. Eyes with CNV developed macular atrophy. The fusion of patchy atrophy, the development of CNV, and macular atrophy all led to significant visual decreases. A posterior staphyloma was observed more frequently in eyes that showed progression from tessellated fundus, diffuse atrophy, and patchy atrophy than those without a progression. CONCLUSIONS: These findings indicate that myopic maculopathy tends to progress in approximately 40% of highly myopic eyes, and the pattern of progression affects the visual prognosis. Preventive therapy targeting posterior staphyloma should be considered to prevent the visual impairment caused by the progression of myopic maculopathy.

Characteristics of peripapillary detachment in pathologic myopia.

OBJECTIVE: To evaluate the prevalence and clinical features of a newly recognized peripapillary lesion specific to high myopia, peripapillary detachment in pathologic myopia (PDPM), in a large series of patients with high myopia. METHODS: Three hundred twenty-four patients (632 eyes) with high myopia were enrolled in this study. We examined the prevalence, range, fluorescein and indocyanine green angiographic findings, and optical coherence tomography findings of PDPM for these patients. Visual field testing (Goldmann kinetic perimetry and the Humphrey 30-2 program) was also performed in the patients with PDPM. RESULTS: Peripapillary detachment in pathologic myopia was identified in 31 of 632 highly myopic eyes (4.9%). The optical coherence tomographic scan across the PDPM lesion revealed a localized detachment of retinal pigment epithelium adjacent to the optic nerve. Although PDPM was always situated adjacent to the inferior edge of the optic disc, in some patients it surrounded almost the entire optic disc. There was a steep excavation of the inferior myopic conus adjacent to the PDPM, and the inferotemporal retinal vein was markedly bent at the transition from the PDPM to the excavated myopic conus. Glaucomatous visual field defects were frequently detected in eyes with PDPM (71.0%). CONCLUSIONS: The findings of this study indicate that PDPM is not uncommon among highly myopic eyes. Although its pathogenesis and pathologic significance require further classification, PDPM might be another indicator of visual field defects in high myopia.

Fundus characteristics of high myopia in children.

PURPOSE: To evaluate the fundus characteristics of highly myopic eyes in children. METHODS: We reviewed the medical records of 46 children (1 to 8 years old; mean age, 6.8 years) (80 eyes) with high myopia (4 D or more for children younger than 5 years, 6 D or more for children aged 6-8 years) seen consecutively during a 10-year period at the high-myopia clinic in our hospital. Children of up to 8 years of age at the initial visit were included in the study. RESULTS: Fundus examination revealed posterior staphyloma in only one eye (1.3%) and mild chorioretinal atrophy around the optic disc in 13 eyes (16.3%). There were no patients with choroidal neovascularization or geographic atrophy in the posterior fundus. Myopic peripapillary crescent was observed in 26 eyes (33.8%), but the area of the crescent was relatively small (mean, 0.5 disc area). CONCLUSIONS: The results of the present study showed that myopic fundus changes are uncommon and mild in children. They suggest that aging, in addition to mechanical stretching of the eyeball, might be important for the development of myopic fundus changes.

Characteristics of patients with a favorable natural course of myopic choroidal neovascularization.

OBJECTIVE: To identify the characteristics of patients with myopic choroidal neovascularization (CNV) who had a favorable visual prognosis without treatment. METHODS: We reviewed the medical records of 52 consecutive patients (57 eyes) with myopic CNV who were followed for at least 5 years after the onset of CNV. Clinical characteristics (patient age, CNV size and location, visual acuity at onset, chorioretinal atrophy development around CNV, and degree of myopia) were compared between patients whose visual acuity 5 years after CNV onset was better than 20/40 and those whose visual acuity was worse than 20/200. RESULTS: Among 57 eyes, eight eyes (14.0%; 8 patients) had a final visual acuity better than 20/40. On the other hand, 37 eyes (64.9%; 33 patients) had a final visual acuity worse than 20/200. Statistical analysis revealed that the patients with a good prognosis (final visual acuity better than 20/40) were significantly younger, had significantly smaller CNV, and significantly better initial visual acuity (Mann-Whitney U-test, p<0.05). Juxtafoveal CNV was more frequently observed in patients with a good prognosis than in those with a poor prognosis (Fisher's exact probability test, p<0.05). Only one patient (12.5%) in the good prognosis group developed a very limited area of chorioretinal atrophy around the regressed CNV, while 91.9% of the patients in the poor prognosis group developed chorioretinal atrophy. Refractive status and the axial length measurements did not differ between the two groups. CONCLUSIONS: Some young patients with myopic CNV retain favorable vision over the long term without active treatment. These information might be useful to predict the visual outcome of patients with myopic CNV.

[The posterior portion of the eyeball and the muscle cone in cases of high myopia].

PURPOSE: To study the displacement of the eyeball of high myopia in the muscle cone. METHODS: Three patients with esotropia with high myopia(myopic esotropia group), seven patients with high myopia without esotropia (high myopia group), and eight controls(control group) were examined. Using magnetic resonance imaging, the outer axial length and the displacement of the posterior portion of the eyeball in the muscle cone were measured. In order to neglect individual differences, the coronal scanning was perpendicular to the orbital axis. The displacement was measured in the plane 2 mm and 4 mm anterior from the globeoptic nerve junction. The distance of the displacement was represented by the distance from the center of the globe to the center of the muscle cone. RESULTS: The displacement in the plane 4 mm anterior (mean +/- standard deviation) was greater in the order of the myopic esotropia group(1.6 +/- 0.64 mm), the high myopia group(1.2 +/- 0.51 mm), and the control group(0.059 +/- 0.35 mm). The displacement of the eyeball was largest in the myopic esotropia group(p < 0.001). The outer axial length and the distance of the displacement in all cases was correlated significantly(r = 0.93, p < 0.01). Moreover, the eyeballs of the myopic esotropia group and the high myopia group were displaced upwards in the temporal area. CONCLUSIONS: The posterior portion of high myopia was displaced upwards in the temporal area in the muscle cone regardless of the presence or absence of esotropia. The eyeball originally elongates upwards in the temporal area, not towards the weakest part of the muscle cone.

Reduction of retinal blood flow in high myopia.

PURPOSE: To investigate changes in retinal vessel diameter and blood velocity in high myopia using laser Doppler velocimetry. METHODS: Thirty-nine subjects (39 eyes) were enrolled in the study. The subjects were divided into three groups according to their refractive status; 15 eyes (15 patients) with emmetropia (within +/-3.0 diopters), 14 eyes (14 patients) with mild myopia (between -3.0 and -8.0 diopters), and 10 eyes (10 patients) with high myopia (>-8.0 diopters). Patient age was matched between groups. Blood velocity and vessel diameter of the upper or lower temporal retinal artery were measured using laser Doppler velocimetry with an eye-tracking system, and measurements were compared between groups. RESULTS: The average retinal blood flow and vessel diameter in highly myopic eyes were significantly decreased compared with emmetropic eyes or mild myopic eyes (Mann-Whitney U test, p<0.05). Also, there was significant difference regarding retinal blood flow and vessel diameter between eyes with mild myopia and the other groups. In addition, there was no significant difference in blood velocity between the three groups. CONCLUSIONS: Retinal blood flow was decreased in high myopia, mainly due to the narrowing of the retinal vessel diameter. Impaired retinal blood flow might have a role in the development of chorioretinal atrophy in high myopia.

Factors associated with the development of chorioretinal atrophy around choroidal neovascularization in pathologic myopia.

PURPOSE: To examine the influencing factors on the development of chorioretinal atrophy, which is the main cause of long-term visual decrease in myopic choroidal neovascularization (CNV), in a large series of highly myopic patients. METHODS: Sixty-five patients (81 eyes) with myopic CNV were studied retrospectively. The influence of the patient's age, refractive error, axial length, visual acuity at onset of CNV, size of CNV, and grade of myopic retinopathy on the extent of chorioretinal atrophy more than 3 years after CNV onset was investigated by means of multiple linear regression analysis. RESULTS: Seventy-seven of 81 eyes (95.1%) developed chorioretinal atrophy around myopic CNV during the follow-up period. Multiple linear regression revealed that age was the most influencing factor for the development of chorioretinal atrophy in all the subjects. When we divided the subjects into two groups according to their age, however, CNV size was the only factor to influence the development of chorioretinal atrophy in the patients younger than 40 years, whereas age was still the only influencing factor in those older than 40 years. CONCLUSIONS: The factors influencing the development of chorioretinal atrophy differ according to patient age. Local factors, such as CNV size, determine the tendency to develop chorioretinal atrophy in young patients. Systemic factors, such as patient age, play a greater part in older subjects.

Myopic choroidal neovascularization: a 10-year follow-up.

PURPOSE: To clarify the long-term visual outcome of choroidal neovascularization (CNV) in eyes with high myopia in Asian patients. DESIGN: We reviewed the medical records of 25 consecutive patients (27 eyes) with myopic CNV who were followed up for at least 10 years after the onset of CNV. Visual acuity was examined 10 years after CNV onset. INTERVENTION: Demographic and clinical data were obtained from the patients' medical records. MAIN OUTCOME MEASURES: Visual acuity readings during the 10 years after CNV onset. RESULTS: At the onset of CNV, 19 eyes (70.4%) had a visual acuity better than 20/200, and six eyes (22.2%) had a visual acuity better than 20/40. Three years after the onset of CNV, 15 eyes (55.5%) retained a visual acuity of better than 20/200. At 5 and 10 years after the onset, however, visual acuity dropped to 20/200 or less in 24 eyes (88.9%) and in 26 eyes (96.3%), respectively. The logarithm of the minimum angle of resolution (logMAR) visual acuity was significantly worse at 5 and 10 years after onset as compared with that at CNV onset. Chorioretinal atrophy developed around the regressed CNV in 26 eyes (96.3%) at 5 and 10 years after the onset of CNV. CONCLUSIONS: Long-term visual outcome of myopic CNV is extremely poor. The visual acuity of almost all of the patients dropped to 20/200 or less within 5 to 10 years after the onset of CNV, secondary to the development of chorioretinal atrophy around the regressed CNV. These findings indicate that active treatments should be recommended to prevent long-term visual impairment in Asian patients with myopic CNV.

Prevalence and characteristics of foveal retinal detachment without macular hole in high myopia.

PURPOSE: To report the prevalence of foveal retinal detachment without macular hole in a large number of highly myopic eyes using optical coherence tomography (OCT), and to clarify the demographic characteristics associated with foveal retinal detachment in these eyes. DESIGN: A consecutive, prospective, observational case series. METHODS: In 134 eyes of 78 consecutive patients with high myopia (refractive error of -8 diopters or more), we performed complete ophthalmic examinations and studied cross-sectional images of the macula with OCT. The patients were divided into two groups according to the presence (group 1, n = 78 eyes of 45 patients) or absence (group 2, n = 56 eyes of 33 patients) of posterior staphyloma. Slit-lamp examination with a Goldmann three-mirror lens indicated that none of the eyes had a macular hole. RESULTS: In seven of 78 eyes (9.0%) with posterior staphyloma (group 1), OCT revealed foveal retinal detachment. Two of the seven eyes had foveal retinoschisis. Optical coherence tomography revealed no retinal detachment or retinoschisis in any eye without posterior staphyloma (group 2). Visual acuity of the seven eyes with foveal retinal detachment ranged from 20/40 to 20/200. Two of the seven eyes had visual acuity 20/50 or better. No patients complained of recent, progressive visual impairment. All seven eyes with foveal retinal detachment had severe myopic fundus changes (focal chorioretinal atrophy or bare sclera). CONCLUSIONS: In highly myopic eyes with posterior staphyloma, the prevalence of foveal retinal detachment without macular hole was 9.0%. In eyes with this type of retinal detachment, visual acuity varies and foveal retinal detachment tends to be missed on routine examination. Periodic examination using OCT is recommended for highly myopic eyes with severe myopic degenerative changes and posterior staphyloma.

[Morphological findings in progressive esotropia with high myopia].

PURPOSE: Esotropia with high myopia is due to elongation of the eyeball, which becomes too large to fit within the muscle cone. To demonstrate the elongation, we measured the size of the eyeballs. SUBJECTS AND METHODS: Five patients with esotropia with high myopia(myopic esotropia group), 8 patients with high myopia without esotropia(high myopia group), and 10 controls(control group) were examined. Using magnetic resonance imaging, we measured the outer axial length and the maximum transverse size of the eyeballs. RESULTS: The outer axial length(mean +/- standard deviation) was greater in the order of the myopic esotropia group(31.6 +/- 1.59 mm), the high myopia group(27.9 +/- 2.22 mm), and the control group(23.7 +/- 1.59 mm) (p < 0.01). The maximum transverse size was also greater in the order of the myopic esotropia group(25.0 +/- 0.99 mm), the high myopia group (24.9 +/- 1.27 mm), and the control group(23.1 +/- 1.38 mm). The outer axial length of the eyeballs in the myopic esotropia group was significantly longer than in the high myopia group and the control group, and the maximum transverse size was significantly longer than in the control group. CONCLUSIONS: The elongation of the eyeballs of the myopic esotropia group was demonstrated. A high incidence of esotropia may occur when the outer axial length of high myopia is longer than 30 mm.

Long-term visual prognosis of choroidal neovascularization in high myopia: a comparison between age groups.

OBJECTIVE: To analyze visual outcome in highly myopic patients of different age groups with choroidal neovascularization (CNV). DESIGN: Retrospective observational case series. PARTICIPANTS: We reviewed the medical records of 63 consecutive patients (73 eyes) with myopic CNV. The patient population was divided into two groups according to age at onset of CNV (< or =40 and >40 years old). INTERVENTION: Demographic and clinical data were obtained from the patients' medical records. MAIN OUTCOME MEASURES: Visual acuity at least 3 years after CNV diagnosis. RESULTS: Group 1 (< or =40 years old) consisted of 22 patients (26 eyes), and group 2 (>40 years old) consisted of 41 patients (47 eyes). Throughout the follow-up period, group 1 retained better visual acuity than group 2. Almost half the patients in group 1 retained a final visual acuity better than 20/40. No significant change occurred in the logarithm of the minimum angle of resolution (logMAR) in group 1 during follow-up. Group 2 had worse visual acuity at the initial evaluation than did group 1, and a statistically significant worsening of logMAR was found during the follow-up period. More than half of the patients in group 2 had a final visual acuity less than 20/200. In addition, group 2 had a larger area of CNV, and chorioretinal atrophy was more frequently seen after the regression of CNV than in group 1. CONCLUSIONS: The visual prognosis of myopic CNV is influenced by age at onset. The results of this study indicate that patient age at the time of onset of myopic CNV should be considered when determining the therapeutic course.

Optical coherence tomography of choroidal neovascularization in high myopia.

AIM: To investigate morphologic changes in the eye with choroidal neovascularization (CNV) in high myopia using optical coherence tomography (OCT). METHODS: Optical coherence tomography was performed in 35 patients (42 eyes) with myopic CNV. Myopic CNV was divided into active, scar, or atrophic stages based on funduscopic and fluorescein angiographic findings. The characteristics of OCT findings in each stage were identified. RESULTS: In the active stage (11 eyes), OCT clearly displayed a neovascular membrane as a highly reflective dome-like elevation above the retinal pigment epithelium (RPE). No apparent subretinal fluid accumulation around the CNV was identified. In the scar stage (12 eyes), only the surface of the CNV showed high reflectivity, which was markedly attenuated below the surface. In the atrophic stage (19 eyes), the CNV had become totally flat and chorioretinal atrophy around the regressed CNV showed high reflectivity. CONCLUSIONS: Optical coherence tomography demonstrated characteristic features at each stage of myopic CNV. Optical coherence tomography appears to be useful in evaluating the stage and activity of myopic CNV.