Muka Moriyama

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.

Clinical Characteristics of Posterior Staphyloma in Eyes with Pathologic Myopia

PURPOSE To determine the morphologic features (grade and type) of posterior staphylomas and to analyze the relationship between the morphologic features and the incidence of myopic macular lesions. DESIGN Observational case series. METHODS Two hundred and nine eyes of 108 consecutive patients with high myopia were studied. The grade of staphylomas was determined from B-scan ultrasonographic images across the optic disk. The type of staphyloma was determined by binocular funduscopy and was classified according to the criteria of Curtin. The participants were divided into two groups: younger than 50 years and 50 years and older. The long-term morphologic progression of staphylomas was analyzed in nine patients who were followed up for more than 20 years. RESULTS Ninety percent of 209 eyes had a staphyloma. The prevalence of staphylomas and more advanced grades of staphylomas (> grade 2) were significantly higher in the older than in the younger patients. The higher grades of staphylomas were associated with more severe myopic retinal degeneration. Type II staphyloma was the most prominent overall; however, in older subjects, the incidence of type II was decreased significantly, and that of type IX was increased significantly. The eyes with type IX staphyloma tended to have more severe myopic retinal degeneration than eyes with type II staphylomas. The long-term follow-up study demonstrated a progression from type II to type IX with increasing age. CONCLUSIONS These results suggest that the morphologic features of staphylomas worsens as the patient ages. The progression from type II to type IX probably increases the mechanical tension on the macular area of highly myopic eyes, which then leads to myopic fundus lesions.

Topographic Analyses of Shape of Eyes with Pathologic Myopia by High-Resolution Three-Dimensional Magnetic Resonance Imaging

OBJECTIVE To analyze the topography of human eyes with pathologic myopia by high-resolution magnetic resonance imaging (MRI) with volume rendering of the acquired images. DESIGN Observational case series. PARTICIPANTS Eighty-six eyes of 44 patients with high myopia (refractive error ≥-8.00 diopters [D] or axial length >26.5 mm) were studied. Forty emmetropic eyes were examined as controls. METHODS The participants were examined with an MRI scanner (Signa HDxt 1.5T, GE Healthcare, Waukesha, WI), and T(2)-weighted cubes were obtained. Volume renderings of the images from high-resolution 3-dimensional (3D) data were done by computer workstation. The margins of globes were then identified semiautomatically by the signal intensity, and the tissues outside the globes were removed. MAIN OUTCOME MEASURES The 3D topographic characteristic of the globes and the distribution of the 4 distinct shapes of globes according to the symmetry and the radius of curvature of the contour of the posterior segment: the barrel, cylindric, nasally distorted, and temporally distorted types. RESULTS In 69.8% of the patients with bilateral high myopia, both eyes had the same ocular shape. The most protruded part of the globe existed along the central sagittal axis in 78.3% of eyes and was slightly inferior to the central axis in the remaining eyes. In 38 of 68 eyes (55.9%) with bilateral pathologic myopia, multiple protrusions were observed. The eyes with 2 protrusions were subdivided into those with nasal protrusions and those with temporal protrusions. The eyes with 3 protrusions were subdivided into nasal, temporal superior, and temporal inferior protrusions. The eyes with visual field defects that could not be explained by myopic fundus lesions significantly more frequently had a temporally distorted shape. Eyes with ≥2 protrusions had myopic chorioretinal atrophy significantly more frequently than eyes with ≤1 protrusion. CONCLUSIONS Our results demonstrate that it is possible to obtain a complete topographic image of human eyes by high-resolution MRI with volume-rendering techniques. The results showed that there are different ocular shapes in eyes with pathologic myopia, and that the difference in the ocular shape is correlated with the development of vision-threatening conditions in eyes with pathologic myopia. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Acquired Optic Nerve and Peripapillary Pits in Pathologic Myopia

PURPOSE To examine the incidence and characteristics of pit-like structures around the optic disc and myopic conus in eyes with high myopia. DESIGN Prospective, observational case series. PARTICIPANTS We evaluated 198 eyes of 119 patients with pathologic myopia (spherical equivalent >-8 diopters [D]). We also evaluated 32 eyes of 32 subjects with emmetropia (refractive error ≤±3 D) as controls. METHODS The papillary and peripapillary areas were examined with a prototype swept-source optical coherence tomography (OCT) system with a center wavelength of 1050 nm. We studied the structural characteristics of pit-like changes. MAIN OUTCOME MEASURES The incidence and characteristics of the optic nerve (ON) pits in eyes with high myopia. RESULTS Pit-like clefts were found at the outer border of the ON or within the adjacent scleral crescent in 32 of 198 highly myopic eyes (16.2%) but in none of the emmetropic eyes. The eyes with these pits were more myopic, had significantly longer axial lengths, and had significantly larger optic discs than the highly myopic eyes without pits. The pits were located in the optic disc area (optic disc pits) in 11 of 32 eyes and in the area of the conus outside the optic disc (conus pits) in 22 of 32 eyes. One eye had both optic disc pits and conus pits. The optic disc pits existed in the superior or inferior border of the optic disc. All but 1 eye with conus pits had a type IX staphyloma, and the location of the conus pits were present nasal to the scleral ridge or outside the ridge temporal to the nerve. The optic disc pits were associated with discontinuities of the lamina cribrosa, whereas the conus pits appeared to develop from a scleral stretch-associated schisis or to emissary openings for the short posterior ciliary arteries in the sclera. The nerve fiber tissue overlying the pits was discontinuous at the site of the pits. CONCLUSIONS Optic nerve pits are common in highly myopic eyes. The ON pits are barely visible ophthalmoscopically but can be demonstrated by using swept-source OCT.

Comparison of Visual Outcome and Regression Pattern of Myopic Choroidal Neovascularization After Intravitreal Bevacizumab or After Photodynamic Therapy

PURPOSE To compare the 1-year visual and anatomic outcomes in myopic eyes with choroidal neovascularization (CNV) treated by intravitreal bevacizumab (IVB) to those treated by photodynamic therapy (PDT). DESIGN An open-label, consecutive, interventional case series. METHODS Forty-four eyes of 42 consecutive patients with myopic CNV treated with PDT, and 43 eyes of 43 consecutive patients with myopic CNV treated with IVB, were evaluated. For control, 74 eyes of 71 consecutive patients with untreated myopic CNV were evaluated. The comparison of best-corrected visual acuity (BCVA) using analysis of covariance (ANCOVA) during the 12-month follow-up period was performed among the 26 IVB-treated patients without prior treatment, 35 PDT-treated patients without prior treatment, and 71 nontreated controls. RESULTS Thirty-nine of the IVB-treated eyes (91%) had angiographic closure, and 21 (48.8%) had an improvement of >2 lines in the BCVA at 1 year. IVB-treated patients had significantly better BCVA than PDT-treated and control eyes at 1 year. The CNV size continued to decrease during the 12-month follow-up in the successfully treated IVB eyes, and the size did not decrease, or even increased, in 65% of the successfully treated PDT eyes. Chorioretinal atrophy developed significantly more frequently in PDT-treated than IVB-treated eyes. CONCLUSIONS IVB is more effective for myopic CNV than PDT. The differences in the regression pattern of CNVs and the rate of chorioretinal atrophy probably explain the better BCVA in the IVB-treated 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 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.

Association between shape of sclera and myopic retinochoroidal lesions in patients with pathologic myopia.

PURPOSE The purpose of the study was to analyze the shape of the sclera determined by swept-source optical coherence tomography (OCT) and to determine the relationship between the shape and the myopic retinochoroidal lesions. METHODS We studied 488 eyes of 272 patients with high myopia (refractive error ≥-8.00 diopters [D] or axial length >26.5 mm) and 43 emmetropic eyes of 43 controls (refractive error ≤±3 D). An image of the sclera was obtained by a swept-source OCT prototype instrument that uses a wavelength sweeping laser centered on 1 μm wavelength with an A-scan repetition rate of 100,000 Hz. The scans were 12 mm radial scans centered on the fovea. Seventy eyes were also examined by three-dimensional magnetic resonance imaging (3D MRI) to obtain the contour of the outer surface of the eyes. The main outcome measures, visibility of the entire sclera layer, scleral thickness, scleral contour, and location of the most protruded point of the globe, were obtained by swept-source OCT and 3D MRI. RESULTS The entire thickness of the sclera was observed in 278 of 488 (57.0%) highly myopic eyes, but the outer border was not observed in any of the emmetropic eyes. The mean subfoveal scleral thickness was 227.9 ± 82.0 μm in the highly myopic eyes. The sclera was thickest at 3000 μm nasal to the fovea. The curvatures of the inner scleral surface of highly myopic eyes could be divided into curvatures that sloped toward the optic nerve, those that were symmetrical and centered on the fovea, those that were asymmetrical, and those that were irregular. Patients with irregular curvature were significantly older and had significantly longer axial lengths than those with other curvatures. Myopic fundus lesions were present significantly more frequently in the eyes with irregular curvature. All of the eyes whose scleral curvature sloped toward the optic nerve had nasally distorted shape in the 3D MRI images, and all eyes with temporally dislocated shape had irregular curvature. CONCLUSIONS In vivo evaluations of the sclera in highly myopic eyes by swept-source OCT can provide important information on deformations of the sclera and how such deformities are related to myopic fundus lesions.

Imaging Retrobulbar Subarachnoid Space around Optic Nerve by Swept-Source Optical Coherence Tomography in Eyes with Pathologic Myopia

PURPOSE To examine the subarachnoid space (SAS) of eyes with pathologic myopia and analyze the characteristics of the SAS and the surrounding tissues by swept-source optical coherence tomography (OCT). METHODS One hundred thirty-three eyes of 76 patients with pathologic myopia (spherical equivalent refractive error of >-8.00 diopters (D) or an axial length >26.5 mm) and 32 eyes of 32 subjects with emmetropia were enrolled. The eyes in both groups were not tested to determine whether glaucoma was present. The papillary and peripapillary areas were examined with a swept-source OCT prototype system that uses a wavelength sweeping laser operated at 100,000 Hz A-scan repetition rate in 1-μm wavelength. RESULTS In the B-scan images, the arachnoid trabeculae inside the SAS were clearly observed as a pattern of reticular lines and dots interspersed with hyporeflective zones consistent with fluid, whereas orbital fat had more uniform features with gray intervening spaces. The SAS was triangular, with the base toward the eye surrounding the optic nerve in the region of the scleral flange. An SAS was found in 124 highly myopic eyes (93.2%) but not in the emmetropic eyes. The shortest distance between the inner surface of lamina cribrosa and SAS was 252.4 ± 110.9 μm, and the thinnest region of peripapillary sclera above SAS (scleral flange thickness) was 190.6 ± 51.2 μm. In one myopic patient, there appeared to be direct communication between the intraocular cavity and SAS through pitlike pores. CONCLUSIONS Optic SAS is seen in 93% of highly myopic eyes, and the SAS appears to be dilated in highly myopic eyes. The expanded area of exposure to CSF pressure along with thinning of the posterior eye wall may influence staphyloma formation and the way in which certain diseases, such as glaucoma, are manifested.

Two-year Outcomes Of Intravitreal Bevacizumab For Choroidal Neovascularization In Japanese Patients With Pathologic Myopia

Purpose: To determine the 2-year results of intravitreal bevacizumab in highly myopic eyes with choroidal neovascularization (CNV). Methods: An open-label, consecutive, interventional case series. Seventy-five eyes of 69 consecutive Japanese patients with either subfoveal or nonsubfoveal myopic CNVs were studied. The eyes were treated with intravitreal bevacizumab and followed-up for at least 2 years. The best-corrected visual acuities at the baseline in eyes with subfoveal CNV were compared with that in eyes with nonsubfoveal CNV at 2 years after the intravitreal bevacizumab. Results: The difference between the mean best-corrected visual acuity at the baseline and that at 2 years in eyes with a subfoveal CNV was not significant. However, the mean best-corrected visual acuity in eyes with nonsubfoveal CNV was significantly improved from 0.53 ± 0.36 logarithm of the minimal angle of resolution units (Snellen 20/66) before intravitreal bevacizumab to 0.29 ± 0.36 logMAR units (Snellen 20/40) (P < 0.001) 2 years after intravitreal bevacizumab. The incidence of chorioretinal atrophy after 2 years was 3 of 49 (6.1%) in eyes with nonsubfoveal CNV and 21 of 26 (80.8%) in eyes with which subfoveal CNV (P < 0.001). Furthermore, the chorioretinal atrophy area with nonsubfoveal CNV was 0.05 ± 0.21 mm2, which was also significantly smaller than that of subfoveal CNV at 1.76 ± 1.60 mm2 (P < 0.001). Conclusion: Intravitreal bevacizumab is a good treatment for eyes with nonsubfoveal CNV; however, another treatment is necessary for eyes with a subfoveally located CNV.