FEMTOSECOND LASER CAN CAUSE CHOROIDAL RUPTURE Ki Hwang Lee, MD, Ho Min Lew, MD, Hong Seok Yang, MD
Purpose: Many studies have found that it is very difficult to create choroidal lesions using a femtosecond laser. However, a patient with a premacular hemorrhage in the left eye and a choroidal rupture in the right eye from exposure to reflection of a femtosecond laser from a metal is described. Methods: The patient was treated with intravitreal expansile gas to displace the premacular blood in the left eye on posttrauma day 2. Patients: A 51-year-old man presented with blind spots in both eyes after being exposed to reflection of a femtosecond laser from a metal. Results: At the 10-week follow-up, the patient’s vision improved to 20/40 (20/30 with a pinhole in the left eye). Discussion: This case suggests that choroidal rupture may occur with use of a femtosecond laser system. RETINAL CASES & BRIEF REPORTS 3:351–353, 2009
From the Department of Ophthalmology, Ajou University Hospital, Suwon, Republic of Korea.
membrane (Fig. 4). The patient was treated with intravitreal expansile gas, using an intravitreal injection of tissue plasminogen activator to displace the premacular blood in the left eye on posttrauma day 2. At the 10-week follow-up, the patient’s vision improved to 20/40 (20/30 with a pinhole in the left eye). However, a blind spot in the right eye, which was shaped like a cross at an angle, leaning left and central scotoma in the left eye remained.
A
lthough premacular hemorrhage induced by a femtosecond laser has been reported,1,2 it is very unlikely to damage Bruch membrane. We describe a patient with a premacular hemorrhage in the left eye and a choroidal rupture in the right eye from exposure to reflection of a femtosecond laser from a metal.
Discussion Macular hemorrhage can occur after using a femtosecond laser. To our knowledge, there are only two reports of femtosecond laser–induced macular hemorrhages. Cooper et al1 described a 34-year-old chemistry professor with a premacular hemorrhage who had been accidentally exposed to reflected light from a femtosecond laser while not wearing safety goggles, and Principe et al2 reported a macular hemorrhage after laser in situ keratomileusis with femtosecond laser flap creation. Several theoretical and animal model studies have examined the safety standards for femtosecond laser systems, and it has been observed that it is very difficult to create a choroidal lesion, even at energies that are 100 times the minimal energy needed to create a visible lesion.1,3 The nonlinear optical effects of self-focusing and laser-induced breakdown account for the lack of damage to Bruch membrane and the choroid.1 Choroidal ruptures usually arise from sudden hyperexpansion of the globe caused by blunt force and are
Case Report A 51-year-old man presented with blind spots in both eyes after being exposed to reflection of a femtosecond laser from a metal, although he was wearing protective glasses. This laser delivers 1 W of 800-nm output at repetition rates of 1 kHz. Refractive errors were emmetropia in the right eye and ⫺0.25 ⫹ 0.50 ⫻ 180 in the left eye, with best-corrected visual acuity of 20/20 in the right eye and 20/200 in the left eye. Funduscopy showed a focal hemorrhage in the left fovea, while the right eye was normal (Fig. 1). Fluorescein angiography revealed an area of hypofluorescence in the left fovea, and a hyperfluorescent vertical line in the posterior retina of the right eye (Figs. 2 and 3). Indocyanine green angiography of the right eye disclosed a hypofluorescent vertical line in the early through late phases, which was compatible with rupture of Bruch
None of the authors has a financial or proprietary interest in any material or method mentioned in this report. Reprint requests: Ho Min Lew, MD, Department of Ophthalmology, Ajou University School of Medicine, San 5, Wonchondong, Youngtong-gu, Suwon, 443-721, Republic of Korea; e-mail: [email protected]
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Fig. 1. Fundus photograph showing a premacular hemorrhage.
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Fig. 3. During the venous phase of fluorescein angiography, a hyperfluorescent vertical line compatible with a choroidal rupture is seen.
generally crescent shaped and oriented relative to the optic disk.4 Another usual form of rupture of Bruch membrane is a lacquer crack, which is a typical feature of degenerative myopia with an axial length ⬎26.5 mm.5,6 Lacquer cracks are linear or stellate, and the lines are fine, irregular in caliber, yellowish white, horizontally oriented, and single or multiple, often branching with crisscrossing.6 Ruiz-Moreno et al7 described a macular hemorrhage and lacquer cracks in a highly myopic female immediately after laser in situ keratomileusis, pos-
sibly due to mechanical stress caused by the intraocular pressure elevation produced by the pneumatic suction ring. However, none of these predisposing factors or a history of trauma was present in our patient, and the shape of the choroidal rupture was not consistent with the results of trauma or lacquer cracks. There is a possibility that the choroidal rupture may be a chronic lesion or unrelated to the event that caused acute hemorrhage in the left eye, because retinal edema
Fig. 2. During the venous phase of fluorescein angiography, a hypofluorescent spot compatible with a premacular hemorrhage is seen.
Fig. 4. Indocyanine green angiography demonstrating a hypofluorescent line corresponding to the hyperfluorescent line seen by fluorescein angiography is apparent.
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FEMTOSECOND LASER CAN CAUSE CHOROIDAL RUPTURE
or leakage in the later phases of the fluorescein angiogram, which would be expected after acute choroidal rupture, is absent in the current case. However, a newly developed blind spot after the event and the lack of subretinal fibrovascular tissue in the right eye may be indications that this unusual lesion is a result of this event. The absence of any accompanying retinal edema and leakage by fluorescein angiography could be explained by a choroidal damage mechanism different than blunt force. The cause of the choroidal rupture in the current case remains obscure. Because this report demonstrates that a choroidal rupture may occur using a femtosecond laser system, additional clinical research is needed to evaluate the risk of damage to Bruch membrane from a femtosecond laser system. Key words: choroidal rupture, femtosecond laser, premacular hemorrhage.
References 1. 2.
3.
4.
5.
6.
7.
Cooper BA, Blinder KJ, Shah GK, et al. Femtosecond laser– induced premacular hemorrhage. Retina 2004;24:812–814. Principe AH, Lin DY, Small KW, et al. Macular hemorrhage after laser in situ keratomileusis with femtosecond laser flap creation. Am J Ophthalmol 2004;138:657–659. Toth CA, Narayan DG, Cain CP, et al. Pathology of macular lesions from subnanosecond pulses of visible laser energy. Invest Ophthalmol Vis Sci 1997;38:2204–2213. Kelly JS. Other disease: traumatic chorioretinopathies. In: Ryan SJ, Schachat AP, eds. Retina. Baltimore, MD: Elsevier Mosby; 2006:1875–1876. Curtin BJ, Karlin DB. Axial length measurements and fundus changes of the myopic eye. Am J Ophthalmol 1971;71: 42–53. Soubrane G, Coscas GJ. Macular disease: choroidal neovascular membrane in degenerative myopia. In: Ryan SJ, Schachat AP, eds. Retina. Baltimore, MD: Elsevier Mosby; 2006:1122–1123. Ruiz-Moreno JM, Montero J, Alio JL, et al. Lacquer crack formation after LASIK. Ophthalmology 2003;110:1669– 1671.
Purpose: Many studies have found that it is very difficult to create choroidal lesions using a femtosecond laser. However, a patient with a premacular hemorrhage in the left eye and a choroidal rupture in the right eye from exposure to reflection of a femtosecond laser from a metal is described. Methods: The patient was treated with intravitreal expansile gas to displace the premacular blood in the left eye on posttrauma day 2. Patients: A 51-year-old man presented with blind spots in both eyes after being exposed to reflection of a femtosecond laser from a metal. Results: At the 10-week follow-up, the patient’s vision improved to 20/40 (20/30 with a pinhole in the left eye). Discussion: This case suggests that choroidal rupture may occur with use of a femtosecond laser system. RETINAL CASES & BRIEF REPORTS 3:351–353, 2009
From the Department of Ophthalmology, Ajou University Hospital, Suwon, Republic of Korea.
membrane (Fig. 4). The patient was treated with intravitreal expansile gas, using an intravitreal injection of tissue plasminogen activator to displace the premacular blood in the left eye on posttrauma day 2. At the 10-week follow-up, the patient’s vision improved to 20/40 (20/30 with a pinhole in the left eye). However, a blind spot in the right eye, which was shaped like a cross at an angle, leaning left and central scotoma in the left eye remained.
A
lthough premacular hemorrhage induced by a femtosecond laser has been reported,1,2 it is very unlikely to damage Bruch membrane. We describe a patient with a premacular hemorrhage in the left eye and a choroidal rupture in the right eye from exposure to reflection of a femtosecond laser from a metal.
Discussion Macular hemorrhage can occur after using a femtosecond laser. To our knowledge, there are only two reports of femtosecond laser–induced macular hemorrhages. Cooper et al1 described a 34-year-old chemistry professor with a premacular hemorrhage who had been accidentally exposed to reflected light from a femtosecond laser while not wearing safety goggles, and Principe et al2 reported a macular hemorrhage after laser in situ keratomileusis with femtosecond laser flap creation. Several theoretical and animal model studies have examined the safety standards for femtosecond laser systems, and it has been observed that it is very difficult to create a choroidal lesion, even at energies that are 100 times the minimal energy needed to create a visible lesion.1,3 The nonlinear optical effects of self-focusing and laser-induced breakdown account for the lack of damage to Bruch membrane and the choroid.1 Choroidal ruptures usually arise from sudden hyperexpansion of the globe caused by blunt force and are
Case Report A 51-year-old man presented with blind spots in both eyes after being exposed to reflection of a femtosecond laser from a metal, although he was wearing protective glasses. This laser delivers 1 W of 800-nm output at repetition rates of 1 kHz. Refractive errors were emmetropia in the right eye and ⫺0.25 ⫹ 0.50 ⫻ 180 in the left eye, with best-corrected visual acuity of 20/20 in the right eye and 20/200 in the left eye. Funduscopy showed a focal hemorrhage in the left fovea, while the right eye was normal (Fig. 1). Fluorescein angiography revealed an area of hypofluorescence in the left fovea, and a hyperfluorescent vertical line in the posterior retina of the right eye (Figs. 2 and 3). Indocyanine green angiography of the right eye disclosed a hypofluorescent vertical line in the early through late phases, which was compatible with rupture of Bruch
None of the authors has a financial or proprietary interest in any material or method mentioned in this report. Reprint requests: Ho Min Lew, MD, Department of Ophthalmology, Ajou University School of Medicine, San 5, Wonchondong, Youngtong-gu, Suwon, 443-721, Republic of Korea; e-mail: [email protected]
351
352
RETINAL CASES & BRIEF REPORTSℜ
Fig. 1. Fundus photograph showing a premacular hemorrhage.
●
2009
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VOLUME 3
●
NUMBER 4
Fig. 3. During the venous phase of fluorescein angiography, a hyperfluorescent vertical line compatible with a choroidal rupture is seen.
generally crescent shaped and oriented relative to the optic disk.4 Another usual form of rupture of Bruch membrane is a lacquer crack, which is a typical feature of degenerative myopia with an axial length ⬎26.5 mm.5,6 Lacquer cracks are linear or stellate, and the lines are fine, irregular in caliber, yellowish white, horizontally oriented, and single or multiple, often branching with crisscrossing.6 Ruiz-Moreno et al7 described a macular hemorrhage and lacquer cracks in a highly myopic female immediately after laser in situ keratomileusis, pos-
sibly due to mechanical stress caused by the intraocular pressure elevation produced by the pneumatic suction ring. However, none of these predisposing factors or a history of trauma was present in our patient, and the shape of the choroidal rupture was not consistent with the results of trauma or lacquer cracks. There is a possibility that the choroidal rupture may be a chronic lesion or unrelated to the event that caused acute hemorrhage in the left eye, because retinal edema
Fig. 2. During the venous phase of fluorescein angiography, a hypofluorescent spot compatible with a premacular hemorrhage is seen.
Fig. 4. Indocyanine green angiography demonstrating a hypofluorescent line corresponding to the hyperfluorescent line seen by fluorescein angiography is apparent.
353
FEMTOSECOND LASER CAN CAUSE CHOROIDAL RUPTURE
or leakage in the later phases of the fluorescein angiogram, which would be expected after acute choroidal rupture, is absent in the current case. However, a newly developed blind spot after the event and the lack of subretinal fibrovascular tissue in the right eye may be indications that this unusual lesion is a result of this event. The absence of any accompanying retinal edema and leakage by fluorescein angiography could be explained by a choroidal damage mechanism different than blunt force. The cause of the choroidal rupture in the current case remains obscure. Because this report demonstrates that a choroidal rupture may occur using a femtosecond laser system, additional clinical research is needed to evaluate the risk of damage to Bruch membrane from a femtosecond laser system. Key words: choroidal rupture, femtosecond laser, premacular hemorrhage.
References 1. 2.
3.
4.
5.
6.
7.
Cooper BA, Blinder KJ, Shah GK, et al. Femtosecond laser– induced premacular hemorrhage. Retina 2004;24:812–814. Principe AH, Lin DY, Small KW, et al. Macular hemorrhage after laser in situ keratomileusis with femtosecond laser flap creation. Am J Ophthalmol 2004;138:657–659. Toth CA, Narayan DG, Cain CP, et al. Pathology of macular lesions from subnanosecond pulses of visible laser energy. Invest Ophthalmol Vis Sci 1997;38:2204–2213. Kelly JS. Other disease: traumatic chorioretinopathies. In: Ryan SJ, Schachat AP, eds. Retina. Baltimore, MD: Elsevier Mosby; 2006:1875–1876. Curtin BJ, Karlin DB. Axial length measurements and fundus changes of the myopic eye. Am J Ophthalmol 1971;71: 42–53. Soubrane G, Coscas GJ. Macular disease: choroidal neovascular membrane in degenerative myopia. In: Ryan SJ, Schachat AP, eds. Retina. Baltimore, MD: Elsevier Mosby; 2006:1122–1123. Ruiz-Moreno JM, Montero J, Alio JL, et al. Lacquer crack formation after LASIK. Ophthalmology 2003;110:1669– 1671.
