Takashi Tokoro

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.

Patchy atrophy and lacquer cracks predispose to the development of choroidal neovascularisation in pathological myopia

Aims: To determine the incidence and predisposing findings for choroidal neovascularisation (CNV) in a large series of highly myopic patients. Methods: The medical records of 218 consecutive patients (325 eyes) with myopic fundus changes in the macula were reviewed. The incidence of CNV during a follow up of at least 3 years of highly myopic patients and identification of predisposing findings for the development of myopic CNV were examined. Results: Among 325 highly myopic eyes examined, 33 eyes (10.2%) developed myopic CNV. The incidence was higher (34.8%) among the fellow eyes of patients with pre-existing CNV than among eyes of patients without pre-existing CNV (6.1%). CNV developed in 3.7% with diffuse chorioretinal atrophy, in 20.0% with patchy atrophy, and in 29.4% with lacquer cracks. Conclusion: Approximately one in 10 highly myopic eyes developed myopic CNV in average 130.2 months. Patchy atrophy and lacquer cracks were shown to be important predisposing findings for CNV development.

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.

Indocyanine green angiography of central serous chorioretinopathy

Indocyanine green angiograms of central serous chorioretinopathy in 30 eyes were evaluated in order to demonstrate the pathologic features of the retinal pigment epithelium. In 5 of the cases, the dye leakage or the pigment epithelial degeneration was seen to be associated with areas of choroidal circulatory insufficiency. This implies that local choroidal ischemia is one of the causes of the pigment epithelial disturbance.

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.

Scleral change in experimentally myopic monkeys.

To elucidate changes in the sclera of myopic eyes free of other obvious pathological features, morphometric and ultrastructural studies on the posterior sclera at the foveola of the three lid-fused monkeys that had developed high myopia were performed. The myopic eyes showed increased axial length, and their scleral thickness was about half that of the control eyes. Furthermore, a gradual increase in the size of collagen bundles and fibrils from the inner to the outer layer of the sclera was observed in the control eyes, but was not evident in the myopic eyes. From the present study, it can be speculated that an alteration of fibrillogenesis in the sclera is a key feature of scleral thinning in lid-suture myopia, and that axial elongation of the eyeball results from a combination of altered fibrillogenesis and mechanical expansion.

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.