|Year : 2014 | Volume
| Issue : 4 | Page : 189-190
Foveoschisis with focal choroidal excavation
Chih-Kang Hsu1, Chun-Cheng Liu2, Jiann-Torng Chen3, Yun-Hsiang Chang3
1 Department of Ophthalmology, Tri-Service General Hospital, Taipei; Department of Ophthalmology, Armed Forces Tao-Yuan General Hospital, Taoyaun; National Defense Medical Center, Taipei, Taiwan
2 Department of Ophthalmology, Armed Forces Tao-Yuan General Hospital, Taoyaun; Department of Optometry, Chung Hwa University of Medical Technology, Tainan, Taiwan
3 Department of Ophthalmology, Tri-Service General Hospital; National Defense Medical Center, Taipei, Taiwan
|Date of Web Publication||1-Oct-2014|
Department of Ophthalmology, Tri-Service General Hospital, National Defense Medical Center, 325 Cheng-Kung Road, Section 2, Neihu District, Taipei 114
Source of Support: None, Conflict of Interest: None
We report a rare case with a focal choroidal excavation (FCE) associated with foveoschisis. We describe the patient’s medical records and review the pertinent literature. A 51-year-old man had an FCE, which was considered to be associated with foveoschisis. Although the patient was treated with repeated intravitreal injection of perfluoropropane, foveoschisis persisted. FCE-linked foveoschisis may be noted in a low myopic patient. Gas tamponade failed to induce retinal reattachment, and aggressive surgical therapy may be needed in this condition.
Keywords: focal choroidal excavation, foveoschisis, optical coherence tomography
|How to cite this article:|
Hsu CK, Liu CC, Chen JT, Chang YH. Foveoschisis with focal choroidal excavation. Taiwan J Ophthalmol 2014;4:189-90
| 1. Introduction|| |
Focal choroidal excavation (FCE) is an area of macular choroidal excavation without evidence of a posterior staphyloma or scleral ectasia. FCE was first reported by Jampol et al in 2006. Previous reports hypothesized congenital malformation or acquired cho-roiditis as the mechanism of FCE formation, and retinochoroidal disorders have never been demonstrated to be associated with FCE.
We present our findings in one case of focal macular choroidal excavation, which is the first reported to involve foveoschisis detected by optical coherence tomography (OCT).
| 2. Case report|| |
A 51-year-old man complained of metamorphopsia and blurred vision in his right eye of 1-week duration. He denied a personal history or a family history of systemic disease. His best corrected visual acuities were 6/10 in the right eye and 6/6 in the left eye. The refractive errors (spherical equivalent) were–3.5 diopters (D) in the right eye and–2.25 D in the left eye. Slit lamp examination showed no abnormality in the anterior segment of either eye. Fundus examination showed pigment mottling in the macula of the right eye [Figure 1]A. OCT demonstrated an FCE with foveoschisis at the macula of the right eye [Figure 1]B. The FCE was bowl-shaped and located just under the fovea. The excavations involved the outer retinal layers up to the external limiting membrane (ELM). The retinal layers from the outer plexiform layer to the retinal nerve fiber layer were almost undisturbed.
|Figure 1: Images of a nonconforming focal choroidal excavation with foveoschisis in the right eye of a 51-year-old man. (A) Fundus photograph showing pigment mottling in the macula. (B) Spectral-domain optical coherence tomography demonstrates a bowl-shaped (arrow) choroidal excavation located just under the fovea. The excavation involves the outer retinal layer up to the ELM. The band of photoreceptor outer segment tips disappears at the excavation, while the bands of ELM and the inner segment/outer segment junction are fairly well preserved. The retinal layers from the outer plexiform layer to the retinal nerve fiber layer are almost undisturbed. The retina is split by schisis cavities at the outer nuclear layer. ELM = external limiting membrane; NFL = nerve fiber layer; GCL = ganglion-cell layer; IPL = inner plexiform layer; INL = inner nuclear layer; OPL = outer plexiform layer; ONL = outer nuclear layer; ELM = external limiting membrane; IS-OS = inner segment-outer segment membrane; RPE = retinal pigment epithelium.|
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We treated the patient’s right eye with an intravitreal injection of 0.4 mL perfluoropropane, and he maintained a face-down position for 3 weeks. However, foveoschisis was still noted 1 month later. A repeated gas injection was given 1 month after the first injection, but failed to induce retinal reattachment. After 6 months of intravitreal injection, his best corrected visual acuity was still 6/10 in the right eye. After extensive discussion, the patient refused surgical treatment.
| 3. Discussion|| |
Increasing numbers of FCEs have been analyzed recently because of the widespread use of spectral-domain OCT (SDOCT). Margolis et al classified FCE into two types: conforming FCE and nonconforming FCE. In conforming FCE, there is no separation between the photoreceptor tips and the retinal pigment epithelium (RPE). Conforming FCE can, over time, progress to nonconforming FCE, as stress on the outer retina results in separation of the photoreceptor tips from the underlying RPE, leading to visual disturbance.,, Some patients with FCE present with recurrent central serous chorioretinopathy and choroidal neo-vascularization, but the simultaneous development of FCE and foveoschisis has not been reported previously.
Foveoschisis refers to a splitting of the neurosensory retina, and is usually noted in highly myopic patients and those with X-linked retinoschisis (XLRS). However, there has been no previous report of foveoschisis secondary to FCE. In this patient, examinations revealed no specific findings such as optic pits, myopic degeneration with staphyloma, or vitreoretinal traction, and we presume that the foveoschisis might have been triggered by FCE.
The development of FCE-linked foveoschisis may be related to the complex of the outward force of the FCE and vitreoretinal adhesion. Histological studies show that in XLRS, the splitting occurs in the nerve fiber layer, whereas in myopic traction macul-opathy (MTM), the level of splitting is usually deeper within the retina. Our patient showed splitting in the outer retinal layer up to the ELM, which is more like MTM. We speculate that FCE and myopic foveoschisis have similar mechanisms.
Previous studies suggest that a simple gas injection achieves retinal reattachment in more than 50% of cases of myopic foveo-schisis. In our patient, repeated gas injections failed to achieve reattachment. Johnson argues that MTM is caused by failure of a pre-retinal structure, such as the posterior vitreous detachment, the epiretinal membrane, and the internal limiting membrane. Surgical repair can be tailored successfully only after identifying the major traction mechanism. Gas tamponade is helpful only in eyes with a macular hole-associated macular detachment. We presumed that the injected gas would act more widely on the dome of the staphyloma and facilitate reattachment of the retina, but this may not be true in cases of focal excavation.
In summary, foveoschisis may be triggered by FCE. Careful examination with OCT and prompt treatment is necessary.
Conflicts of interest: The authors have no conflicts of interest relevant to this article.
| References|| |
Margolis R, Mukkamala SK, Jampol LM, Spaide RF, Ober MD, Sorenson JA, et al. The expanded spectrum of focal choroidal excavation. Arch Ophthalmol
Katome T, Mitamura Y, Hotta F, Niki M, Naito T. Two cases of focal choroidal excavation detected by spectral-domain optical coherence tomography. Case Report Ophthalmol
Kumano Y, Nagai H, Enaida H, Ueno A, Matsui T. Symptomatic and morphological differences between choroidal excavations. Optom Vis Sci
Wu TY, Yang CH, Yang CM. Gas tamponade for myopic foveoschisis with foveal detachment. Graefes Arch Clin Exp Ophthalmol
Johnson MW. Myopic traction maculopathy: pathogenic mechanisms and surgical treatment. Retina