Unfortunately, the scan length of currently available OCT machines is not long enough to cover the extent of wide macular staphyloma. However, because of advances in OCT technology, ultra-widefield OCT could become a powerful tool to determine the presence and type of posterior staphyloma in the near future.
Because posterior staphyloma is an important feature and the ideal treatment strategies to prevent BCVA loss should target staphyloma, defining PM based on the presence of staphyloma by using ultra-widefield OCT would be expected.
DETAILED CHARACTERISTICS OF MYOPIC MACULOPATHY LESIONS
Diffuse Chorioretinal Atrophy
Because PM is defined by the presence of atrophy equal to or more severe than diffuse atrophy, the proper diagnosis of diffuse atrophy is clinically important. Diffuse chorioretinal atrophy (Fig. 7) can be identified by the yellowish-white appearance of the posterior pole. The extent of the diffuse atrophy may vary from a restricted area around the optic disc and part of the macula to the entire posterior pole. The area of atrophy generally first appears around the optic disc, often increasing with age, and finally covers the entire area within the staphyloma. Both age and axial length have been described as risk factors for the development of diffuse atrophy.22 Yokoi et al recently found that peripapillary diffuse atrophy was an important indicator in children to predict eventual PM in adults.
Marked thinning of the choroid in the area of diffuse atrophy can be appreciated on OCT, with occasional sporadic large choroidal vessels remaining (Fig. 7). The choroid is disproportionally thinned compared with the thinning of retina and sclera. This extreme thinning of the choroid is a fundamental characteristic for diffuse atrophy (and also for PM).
Patchy Chorioretinal Atrophy
Patchy chorioretinal atrophy (Fig. 8) appears as a well-defined, grayish-white lesion(s) in the macular area. Patchy chorioretinal atrophy is characterized by a complete loss of choriocapillaris and can progress to the absence of outer retina and RPE. Recent analyses using the most updated swept-source OCT showed that patchy atrophy was not simply chorioretinal atrophy but was Bruch membrane hole, as shown for the peripapillary gamma zone23 and for myopic CNV-related macular atrophy.24 Because of the inherent elasticity of the Bruch membrane, once a defect is created, it would be expected to increase over time.
Lacquer cracks (Fig. 9) appear as yellowish linear lesions in the macula. They can often be seen to crisscross over the underlying choroidal vessels. Lacquer cracks are believed to represent mechanical breaks of the Bruch membrane.7,22,25,26 They may appear as linear horizontal or vertical cracks or exhibit a crisscrossing pattern.27 Lacquer cracks show clear hyperfluorescence on fluorescein angiogram and show hypofluorescence in the late phase of indocyanine green angiography. It is difficult to detect this lesion with OCT, mainly because the lesion is too narrow. Thus, it is not clear whether ophthalmoscopically observed lacquer cracks truly represent Bruch membrane rupture. When lacquer cracks are newly formed, simple macular bleeding is observed. This hemorrhage is spontaneously absorbed, and lacquer cracks are observed later.
Myopic CNV (Fig. 10) is a common cause of the loss of central vision in patients with PM. On the basis of published studies, it has been estimated that the prevalence of myopic CNV ranges from 5% to 11% among individuals with high myopia.22,28–30
Optical coherence tomography is useful for the detection of myopic CNV. Exudative changes around the CNV tend to be milder than CNV due to age-related macular degeneration.
On clinical examination, myopic CNV typically appears as a flat, small, grayish subretinal lesion beneath or near the fovea with or without hemorrhage. There are usually minimal subretinal fluid or exudative changes associated with myopic CNV. The diagnosis of myopic CNV can be confirmed by fluorescein angiogram and spectral domain OCT. Fluorescein angiogram findings in myopic CNV usually demonstrate well-defined hyperfluorescence in the early phase, with a classic CNV pattern of leakage in the late phase. Spectral domain OCT has the advantage of being noninvasive and fast to perform.
Antiangiogenesis treatment with intravitreal antivascular endothelial growth factor (anti-VEGF) therapy has become the standard-of-care first-line treatment for myopic CNV.31 Two large multicenter, double-masked, randomized, controlled clinical trials have been performed to evaluate the use of anti-VEGF therapy for myopic CNV.32,33 The RADIANCE [the ranibizumab and photodynamic therapy (verteporfin) evaluation in myopic CNV] study was a 12-month clinical trial that randomized 275 patients to 2 regimens of intravitreal 0.5 mg ranibizumab versus verteporfin photodynamic therapy for the treatment of myopic CNV.32 In the MYRROR study, the use of intravitreal 2 mg aflibercept was compared with a sham control group for the treatment of myopic CNV.33 Both studies showed the effectiveness of anti-VEGF therapy for myopic CNV.
Several studies have evaluated the long-term outcomes of anti-VEGF therapy for myopic CNV. In a retrospective study by Lai et al,34 37 treatment-naive eyes of 37 patients with subfoveal myopic CNV were treated with intravitreal bevacizumab or ranibizumab and were observed for at least 2 years. Mean logMAR visual acuity improved significantly from 0.86 to 0.48. The mean visual improvement at 2 years was 2.8 lines for the bevacizumab group and 5.1 lines for the ranibizumab group, but the difference was not statistically significant. Oishi et al35 further evaluated the use of intravitreal bevacizumab in 22 eyes with myopic CNV, and patients were observed for at least 4 years. After intravitreal bevacizumab treatment for myopic CNV, significant visual improvements were observed at 1, 2, and 3 years. The improvement in visual acuity became marginally nonsignificant at 4 years after treatment. The main reason for the slight decline in visual improvement at 4 years might be related to CNV-related macular atrophy. A recent study by Ruiz-Moreno et al,36 which evaluated the 6-year outcome of anti-VEGF therapy in 97 patients with myopic CNV, showed that visual acuity improvement after bevacizumab or ranibizumab treatment was no longer significant after 4, 5, and 6 years. Further studies are necessary to examine whether anti-VEGF therapy is effective in the long-term.
Choroidal Neovascularization–Related Macular Atrophy
After the regression of myopic CNV with or without anti-VEGF therapy, well-defined macular atrophy gradually develops around the scarred CNV. This is known as myopic CNV-related macular atrophy (Fig. 11) and is the main cause of long-term decreased vision in patients with myopic CNV. A recent study using swept-source OCT showed that myopic CNV-related macular atrophy was also a Bruch membrane hole,37 like patchy atrophy. These suggest that Bruch membrane holes might be a common hallmark of lesions of myopic maculopathy.
The site where myopic CNV penetrates into the retina is originally a Bruch membrane hole. In eyes with PM, consistent mechanical tension is loaded on the area within staphyloma. When the penetrating site is not fully regenerated, the Bruch membrane hole continues to enlarge and ends up becoming CNV-related macular atrophy. Thus, approaches to prevent the enlargement of the Bruch membrane hole are necessary to truly improve long-term vision for patients with myopic CNV.
Myopic Traction Maculopathy
Takano and Kishi38 first demonstrated foveal retinal detachment and retinoschisis in severely myopic eyes with posterior staphyloma using OCT. Panozzo and Mercanti39 proposed the term myopic traction maculopathy (MTM; Fig. 12) to encompass various findings with traction on OCT in highly myopic eyes. Myopic traction maculopathy includes retinoschisis, foveal retinal detachment, lamellar or full-thickness macular hole, and/or macular detachment.40 Optical coherence tomography is an indispensable tool for diagnosing MTM.
Shimada et al41 have classified MTM according to its location and extent from S0 through S4: S0, no retinoschisis; S1, extrafoveal; S2, foveal; S3, both foveal and extrafoveal but not the entire macula; and S4, the entire macula. Shimada et al further defined the progression as an increase of the extent or height of retinoschisis (more than 100 μm) or the development of an inner lamellar macular hole, foveal detachment, or full-thickness macular hole.41 They reported progression during a mean follow-up of 36.2 months in 24 (11.6%) of 207 eyes, which included 0.9% who progressed to full-thickness macular hole and 3.4% who progressed to foveal detachment. The eyes with extensive macular retinoschisis (S4) showed progression significantly more (42.9%) than eyes having less extensive macular retinoschisis areas (6.7%). Six (21.4%) of 28 eyes with S4 MTM progressed to foveal detachment.
The formation of full-thickness macular hole is a serious complication during and after vitrectomy for MTM. A foveolar internal limiting membrane–sparing technique was used in an attempt to reduce the development of macular hole after vitrectomy, which is a severe complication that results in poor visual recovery. Several studies showed good visual and anatomic outcomes with this technique.42–44
Myopic Optic Neuropathy or Glaucoma
The papillary and peripapillary regions of eyes with PM are distorted by the mechanical stretching of the globe. After marked mechanical stretching and distortion of the papillary and peripapillary regions, structural abnormalities occur. Using swept-source OCT, Ohno-Matsui et al45 found pit-like clefts at the outer border of the optic disc or within the adjacent scleral crescent in 32 (16.2%) of 198 highly myopic eyes but none in emmetropic eyes. The pits were located either in the optic disc area, in the optic disc pits, or in the conus area and conus pits, outside the optic disc. The optic disc pits were associated with discontinuities of the lamina cribrosa, whereas the conus pits seemed to develop from a scleral stretch-associated schisis or 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, and this might explain the cause of visual field (VF) defects in highly myopic eyes in some cases. The location of the conus pits might partly explain why the papillomacular bundles tend to be damaged in highly myopic eyes. Peripapillary intrachoroidal cavitation was observed as yellowish-orange lesions located most typically inferior to the optic disc in highly myopic eyes.46,47
Visual field findings are difficult to interpret in eyes with PM. They usually have a large conus together with various extents of myopic maculopathy, which make the analyses and interpretations of automated VF examinations difficult. To overcome the disadvantage of the Humphrey 30-2 automated VF test, Ohno-Matsui et al17 used Goldmann kinetic perimetry and reported that 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. During a mean follow-up of 10.2 ± 3.4 years, 73.8% of eyes had significant progression of VF defects.
Dome-shaped macula (DSM; Fig. 13) was first described by Gaucher et al14 in eyes with myopic posterior staphyloma. A characteristic inward bulge inside the chorioretinal posterior concavity of the eye in the macular area was noted in 15 eyes. Subsequent imaging studies by Imamura et al48 demonstrated that the bulge is associated with a local thickening of the subfoveal sclera.
Liang et al15 reported the prevalence of DSM was 20.1% in a cohort of 1118 eyes in Japanese patients with high myopia. Recently, the prevalence of DSM was evaluated in the RADIANCE study, which recruited 277 eyes with myopic CNV, and DSM was present in 18% of patients.49 Ellabban et al50 reported the macular complications occurring in eyes with DSM, such as CNV and serous retinal detachment.
According to the definition by the META-PM study, PM is easily identified in fundus photos by the presence of diffuse atrophy. This standardized definition enables the direct comparison of the prevalence of PM between races in epidemiological studies. Peripapillary diffuse atrophy is an important indicator to show whether children will eventually develop PM as adults. In the near future, ultra-widefield OCT is expected to become a powerful tool to analyze eye deformities, surpassing 3D MRI techniques. Preventive therapies targeting staphyloma and eye deformities are expected before vision-threatening complications occur.
1. Iwase A, Araie M, Tomidokoro A, et al. Prevalence and causes of low vision and blindness in a Japanese adult population: the Tajimi Study. Ophthalmology
2. Xu L, Wang Y, Li Y, et al. Causes of blindness and visual impairment in urban and rural areas in Beijing: the Beijing Eye Study. Ophthalmology
. 2006;113:1134, e1–11.
3. You QS, Xu L, Yang H, et al. Five-year incidence of visual impairment and blindness in adult Chinese the Beijing Eye Study. Ophthalmology
4. Yamada M, Hiratsuka Y, Roberts CB, et al. Prevalence of visual impairment in the adult Japanese population by cause and severity and future projections. Ophthalmic Epidemiol
5. Hsu WM, Cheng CY, Liu JH, et al. Prevalence and causes of visual impairment in an elderly Chinese population in Taiwan: the Shihpai Eye Study. Ophthalmology
6. Vongphanit J, Mitchell P, Wang JJ. Prevalence and progression of myopic retinopathy in an older population. Ophthalmology
7. Gao LQ, Liu W, Liang YB, et al. Prevalence and characteristics of myopic retinopathy in a rural Chinese adult population: the Handan Eye Study. Arch Ophthalmol
8. Liu HH, Xu L, Wang YX, et al. Prevalence and progression of myopic retinopathy in Chinese adults: the Beijing Eye Study. Ophthalmology
9. Tokoro T, ed. Atlas of Posterior Fundus Changes in Pathologic Myopia
. Tokyo: Springer-Verlag; 1998.
10. Ohno-Matsui K, Kawasaki R, Jonas JB, et al. International photographic classification and grading system for myopic maculopathy
. Am J Ophthalmol
. 2015;159:877–883, e7.
11. Verkicharla PK, Ohno-Matsui K, Saw SM. Current and predicted demographics of high myopia and an update of its associated pathological changes. Ophthalmic Physiol Opt
12. Spaide RF. Staphyloma: Part 1
. New York: Springer; 2013.
13. Curtin BJ. The posterior staphyloma
of pathologic myopia
. Trans Am Ophthalmol Soc
14. Gaucher D, Erginay A, Lecleire-Collet A, et al. Dome-shaped macula in eyes with myopic posterior staphyloma
. Am J Ophthalmol
15. Liang IC, Shimada N, Tanaka Y, et al. Comparison of clinical features in highly myopic eyes with and without a dome-shaped macula. Ophthalmology
16. Spaide RF, Akiba M, Ohno-Matsui K. Evaluation of peripapillary intrachoroidal cavitation with swept source and enhanced depth imaging optical coherence tomography. Retina
17. Ohno-Matsui K, Shimada N, Yasuzumi K, et al. Long-term development of significant visual field defects in highly myopic eyes. Am J Ophthalmol
18. Wang NK, Wu YM, Wang JP, et al. Clinical characteristics of posterior staphylomas in myopic eyes with axial length shorter than 26.5mm. Am J Ophthalmol
. 2016;162:180–190. [Epub ahead of print].
19. Moriyama M, Ohno-Matsui K, Hayashi K, et al. Topographic analyses of shape of eyes with pathologic myopia
by high-resolution three-dimensional magnetic resonance imaging. Ophthalmology
20. Moriyama M, Ohno-Matsui K, Modegi T, et al. Quantitative analyses of high-resolution 3D MR images of highly myopic eyes to determine their shapes. Invest Ophthalmol Vis Sci
21. Ohno-Matsui K. Proposed classification of posterior staphylomas based on analyses of eye shape by three-dimensional magnetic resonance imaging and wide-field fundus imaging. Ophthalmology
22. Hayashi K, Ohno-Matsui K, Shimada N, et al. Long-term pattern of progression of myopic maculopathy
: a natural history study. Ophthalmology
23. Jonas JB, Jonas SB, Jonas RA, et al. Parapapillary atrophy: histological gamma zone and delta zone. PLoS One
24. Ohno-Matsui K, Jonas JB, Spaide RF. Macular Bruch membrane holes in highly myopic patchy chorioretinal atrophy. Am J Ophthalmol
25. Zheng Y, Lavanya R, Wu R, et al. Prevalence and causes of visual impairment and blindness in an urban Indian population: the Singapore Indian Eye Study. Ophthalmology
26. Neelam K, Cheung CM, Ohno-Matsui K, et al. Choroidal neovascularization in pathological myopia. Prog Retin Eye Res
27. Ikuno Y, Sayanagi K, Soga K, et al. Lacquer crack formation and choroidal neovascularization in pathologic myopia
28. Wong TY, Ferreira A, Hughes R, et al. Epidemiology and disease burden of pathologic myopia
and myopic choroidal neovascularization: an evidence-based systematic review. Am J Ophthalmol
. 2014;157:9–25, e12.
29. Curtin BJ, Karlin DB. Axial length measurements and fundus changes of the myopic eye. I. The posterior fundus. Trans Am Ophthalmol Soc
30. Grossniklaus HE, Green WR. Pathologic findings in pathologic myopia
31. Lai TY. Anti-vascular endothelial growth factor therapy for myopic choroidal neovascularization: do we need more evidence? Retina
32. Wolf S, Balciuniene VJ, Laganovska G, et al. RADIANCE: a randomized controlled study of ranibizumab in patients with choroidal neovascularization secondary to pathologic myopia
. 2014;121:682–692, e682.
33. Ikuno Y, Ohno-Matsui K, Wong TY, et al. Intravitreal aflibercept injection in patients with myopic choroidal neovascularization: the MYRROR Study. Ophthalmology
34. Lai TY, Luk FO, Lee GK, et al. Long-term outcome of intravitreal anti-vascular endothelial growth factor therapy with bevacizumab or ranibizumab as primary treatment for subfoveal myopic choroidal neovascularization. Eye (Lond)
35. Oishi A, Yamashiro K, Tsujikawa A, et al. Long-term effect of intravitreal injection of anti-VEGF agent for visual acuity and chorioretinal atrophy progression in myopic choroidal neovascularization. Graefes Arch Clin Exp Ophthalmol
36. Ruiz-Moreno JM, Montero JA, Araiz J, et al. Intravitreal anti-vascular endothelial growth factor therapy for choroidal neovascularization secondary to pathologic myopia
: six years outcome. Retina
37. Ohno-Matsui K, Jonas JB, Spaide RF. Macular Bruch membrane holes in choroidal neovascularization-related myopic macular atrophy by swept-source optical coherence tomography. Am J Ophthalmol
38. Takano M, Kishi S. Foveal retinoschisis and retinal detachment in severely myopic eyes with posterior staphyloma
. Am J Ophthalmol
39. Panozzo G, Mercanti A. Optical coherence tomography findings in myopic traction maculopathy. Arch Ophthalmol
40. Johnson MW. Myopic traction maculopathy: pathogenic mechanisms and surgical treatment. Retina
. 2012;32(Suppl 2):S205–S210.
41. Shimada N, Tanaka Y, Tokoro T, et al. Natural course of myopic traction maculopathy and factors associated with progression or resolution. Am J Ophthalmol
. 2013;156:948–957, e1.
42. Ho TC, Chen MS, Huang JS, et al. Foveola nonpeeling technique in internal limiting membrane peeling of myopic foveoschisis surgery. Retina
43. Shimada N, Sugamoto Y, Ogawa M, et al. Fovea-sparing internal limiting membrane peeling for myopic traction maculopathy. Am J Ophthalmol
44. Ho TC, Yang CM, Huang JS, et al. Long-term outcome of foveolar internal limiting membrane nonpeeling for myopic traction maculopathy. Retina
45. Ohno-Matsui K, Akiba M, Moriyama M, et al. Acquired optic nerve and peripapillary pits in pathologic myopia
46. Freund KB, Ciardella AP, Yannuzzi LA, et al. Peripapillary detachment in pathologic myopia
. Arch Ophthalmol
47. Toranzo J, Cohen SY, Erginay A, et al. Peripapillary intrachoroidal cavitation in myopia. Am J Ophthalmol
48. Imamura Y, Engelbert M, Iida T, et al. Polypoidal choroidal vasculopathy: a review. Surv Ophthalmol
49. Ceklic L, Wolf-Schnurrbusch U, Gekkieva M, et al. Visual acuity outcome in RADIANCE study patients with dome-shaped macular features. Ophthalmology
50. Ellabban AA, Tsujikawa A, Matsumoto A, et al. Three-dimensional tomographic features of dome-shaped macula by swept-source optical coherence tomography. Am J Ophthalmol
Try to be a rainbow in someone’s cloud.
— Maya Angelon
Keywords:© 2016 by Asia Pacific Academy of Ophthalmology
pathologic myopia; posterior staphyloma; myopic maculopathy; myopic optic neuropathy; 3D MRI