Academia.eduAcademia.edu

Tilted Disk Syndrome with Superior Staphyloma

2008, Retinal Cases & Brief Reports

Background: Tilted disk syndrome is a common condition that consists of inferonasal tilting of the optic disk and is usually associated with staphyloma in the inferonasal fundus. Case Report: We describe a 50-year-old woman whose fundus exhibited, in both eyes, all the characteristics of tilted disk syndrome but in an upside-down pattern: superior instead of inferior staphyloma and thinning of the retinal pigment epithelium, a superior instead of an inferonasal crescent, and an inferior instead of a superior visual field defect. Conclusion: We have no satisfactory explanation for this unusual case.

TILTED DISK SYNDROME WITH SUPERIOR STAPHYLOMA Salomon Y. Cohen, MD, PHD, Gabriel Quentel, MD Background: Tilted disk syndrome is a common condition that consists of inferonasal tilting of the optic disk and is usually associated with staphyloma in the inferonasal fundus. Case Report: We describe a 50-year-old woman whose fundus exhibited, in both eyes, all the characteristics of tilted disk syndrome but in an upside-down pattern: superior instead of inferior staphyloma and thinning of the retinal pigment epithelium, a superior instead of an inferonasal crescent, and an inferior instead of a superior visual field defect. Conclusion: We have no satisfactory explanation for this unusual case. RETINAL CASES & BRIEF REPORTS 2:299 –300, 2008 Discussion From Centre Ophtalmologique d’Imagerie et de Laser, Paris, France. Many complications may occur in the area around the margin of staphyloma associated with tilted disk syndrome, including macular pigmentary changes,3 choroidal neovascularization,4 and macular serous retinal detachment.5 In the present case, metamorphopsia was attributed to juxtafoveal pigmentary changes located at the margin of staphyloma. The present case exhibited all the characteristics of tilted disk syndrome but in an upside-down pattern: superior instead of inferior staphyloma and thinning of the retinal pigment epithelium, a superior instead of an inferonasal crescent, and an inferior instead of a superior visual field defect. However, contrary to what is observed in typical tilted disk syndrome, myopia was mild, probably because the macula was located outside the staphyloma. Typical inferior staphyloma of tilted disk syndrome is closely related to inferior staphylomas observed in myopic eyes. These inferior staphylomas correspond to type V staphylomas reported by Curtin.6,7 They are not frequent, observed in only 2.6% of myopic eyes. It should be noted that in the extensive analysis of staphylomas performed by Curtin, no case of superior staphyloma was noted. Tilted disk syndrome is thought to be due to malclosure of the embryonic fissure.2 It is considered a “forme fruste” of coloboma, because the disk–fundus lesion is always located within the reaches of the former embryonic fissure and because the association of congenitally tilted disks with definite colobomas has been clearly documented.2 There is no simple explanation for the present case of what could be called “inverted” tilted disk syndrome, because, to our T ilted disk syndrome is a common condition that is present in 1.6% of eyes.1 It consists of inferonasal tilting of the optic disk and is usually associated with an inferonasal crescent, thinning of the retinal pigment epithelium and choroids, and staphyloma in the inferonasal fundus.2 We describe a patient who had tilted disk syndrome with superior staphyloma. Case Report A 50-year-old woman was referred for mild metamorphopsia in the left eye. Visual acuity was 20/25 (170° ⫺2, ⫺0.50 diopter) in the right eye and 20/20 (30° ⫺1, ⫺0.25 diopter) in the left eye. Fundus examination showed staphyloma and hypopigmentation of the upper part of the retina in both eyes. The lower part of the disk was elevated, and the upper part exhibited a white crescent (Fig. 1). Fluorescein angiography (Fig. 2) and indocyanine green angiography of the left eye revealed pigmentary alterations of the retinal pigment epithelium and atrophic changes at the lower margin of the staphyloma, but no choroidal neovascularization was found. There was a defect in the lower part of the left visual field tested with Goldmann perimetry. B-scanning confirmed the presence of superior staphyloma (Fig. 3). The patient had no systemic malformation. She had no sibling who could have undergone ophthalmic examination. We are unaware of previous reports of similar findings and could find no reference of a similar case in a computerized search of the literature utilizing MEDLINE. Presented in part at the Fluorescein Conference, 29th Annual Meeting of the Macula Society; Aviara, California; February 22– 25, 2006. Reprint requests: Salomon Y. Cohen, MD, PhD, Centre Ophtalmologique d’Imagerie et de Laser, 11 rue Antoine Bourdelle, Paris, France; e-mail: [email protected] 299 RETINAL CASES & BRIEF REPORTSℜ 300 ● 2008 ● VOLUME 2 ● NUMBER 4 Fig. 1. Fundus photographs of the right (A) and left (B) eyes showed superior staphyloma in both eyes. Note the elevation of the lower part of the disk and the white crescent in the upper part. Fig. 2. Fluorescein angiography showed pigmentary changes nasally and temporally to the disk. These areas corresponded to the lower margin of the superior staphyloma. knowledge, possibilities of superior closure of the embryonic ocular fissure and malclosure of this fissure have not been described. These possibilities need to be confirmed by additional data. Key words: tilted disk syndrome, superior staphyloma, malclosure of the embryonic fissure. References 1. Vongphanit J, Mitchell P, Wang JJ. Population prevalence of tilted optic disks and the relationship of this sign to refractive error. Am J Ophthalmol 2002;133:679–685. Fig. 3. Sagittal B-scanning of the left eye. The staphyloma appears as ectasia located in the upper part of the scan. 2. 3. 4. 5. 6. 7. Apple DJ, Rabb MF, Walsh PM. Congenital anomalies of the optic disc. Surv Ophthalmol 1982;27:3–41. Giuffrè G. Chorioretinal degenerative changes in tilted disc syndrome. Int Ophthalmol 1991;15:1–7. Prost M, De Laey JJ. Choroidal neovascularization in tilted disc syndrome. Int Ophthalmol 1988;12:131–135. Cohen SY, Quentel G, Guiberteau B, et al. Macular serous detachment caused by subretinal leakage in tilted disc syndrome. Ophthalmology 1988;105:1831–1834. Curtin BJ. The posterior staphyloma of pathologic myopia. Trans Am Ophthalmol Soc 1977;75:67–86. Curtin BJ. The Myopias. Philadelphia: Harper and Row; 1985.