|Year : 2023 | Volume
| Issue : 1 | Page : 142-144
Bietti crystalline dystrophy complicated by choroidal neovascularization treated with a single dose of aflibercept
Merve Ozbek, Seren Pehlivanoglu, Halil Ozgur Artunay
Department of Ophthalmology, Beyoglu Eye Training and Research Hospital, Istanbul, Turkey
|Date of Submission||08-Jan-2022|
|Date of Decision||17-May-2022|
|Date of Acceptance||29-Jun-2022|
|Date of Web Publication||21-Feb-2023|
Bereketzade Cami SK. No: 234421 Istanbul
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Bietti crystalline dystrophy is a rare hereditary autosomal recessive disease that causes photoreceptor loss secondary to degeneration of retinal pigment epithelium due to intracellular retinal pigment epithelial crystalline deposits and abnormal lipid metabolism. We aimed to present a case of choroidal neovascular membrane secondary to Bietti crystalline dystrophy diagnosed with multimodal imaging and treated with an intravitreal injection of aflibercept. A single dose of aflibercept injection might be effective due to its higher affinity for vascular endothelial growth factor (VEGF) in comparison with other anti-VEGFs. It might be a treatment alternative that can be considered in the choroidal neovascular membrane due to uncommon etiologies.
Keywords: Aflibercept, Bietti crystalline dystrophy, choroidal neovascularization, optical coherence tomography, retinal degenerations
|How to cite this article:|
Ozbek M, Pehlivanoglu S, Artunay HO. Bietti crystalline dystrophy complicated by choroidal neovascularization treated with a single dose of aflibercept. Oman J Ophthalmol 2023;16:142-4
|How to cite this URL:|
Ozbek M, Pehlivanoglu S, Artunay HO. Bietti crystalline dystrophy complicated by choroidal neovascularization treated with a single dose of aflibercept. Oman J Ophthalmol [serial online] 2023 [cited 2023 Mar 26];16:142-4. Available from: https://www.ojoonline.org/text.asp?2023/16/1/142/370065
| Introduction|| |
Bietti crystalline dystrophy (BCD) is a rare hereditary autosomal recessive disease that causes photoreceptor loss secondary to degeneration of retinal pigment epithelium (RPE) due to intracellular retinal pigment epithelial crystalline deposits and abnormal lipid metabolism due to biallelic mutations affecting the cytochrome P450 4V2 (CYP4V2) gene. BCD is characterized by retinal dystrophy with bright yellow crystal deposits at the posterior pole, followed by progressive atrophy of the retina, choriocapillaris, and choroid. In addition, 1/2–1/3 of the patients show bright yellow crystals in the superficial paralimbal cornea.,,
Although the age of onset, symptoms, and severity of the disease varies from person to person, patients usually present them with low vision, night blindness, and visual field narrowing in the third or fourth decade of life. However, progressing to legal blindness in the fifth or sixth decades. In the literature, few studies have reported choroidal neovascular membrane (CNVM), cystoid macular edema, and macular hole in patients with BCD.,
We aimed to present a rare case of CNVM secondary to BCD diagnosed with multimodal imaging and treated with intravitreal injection of aflibercept.
| Case Report|| |
A 34-year-old man presented with progressive visual impairment and deterioration of night vision in both eyes. On initial examination, the best-corrected visual acuity was counting fingers at 3 m in the right eye and 0.3 decimal in the left eye. Slit-lamp examination of the anterior chamber in both eyes was normal. Intraocular pressure was normal. Dilate funduscopic examination showed bilateral, numerous variable-sized yellow-white crystalline deposits scattered throughout the posterior pole. Furthermore, noted that the diffuse chorioretinal atrophy and retinal pigment epithelium alterations around the macular area. Besides, there was a subretinal hemorrhage in the right eye [Figure 1]a. Fundus autofluorescence (FAF) image displays confluent-patched areas of hypoautofluorescence surrounded by diffuse speckled autofluorescence in both eyes [Figure 2]. A preliminary diagnosis with color fundus and FAF image was made as BCD and we reexamined the cornea, but corneal accumulation was not detected. There was no history of systemic disease or drug use in the patient's medical history. Family history was not remarkable in terms of ocular diseases.
|Figure 1: Multimodal imaging of the right eye: Initial examination (a) Fundus photograph showed yellow-white crystalline deposits and subretinal hemorrhage. (b) OCT demonstrated a hyperreflective lesion (c and d) FFA revealed a choroidal neovascular membrane. (e) OCTA image revealed a high-flow network corresponding to the hyperreflective lesion detected on the OCT. OCT - Optic coherence tomography; OCTA - Optical coherence tomography angiography; FFA - Fundus fluorescein angiography|
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Optic coherence tomography (OCT; Heidelberg Engineering, Heidelberg, Germany) and fundus fluorescein angiography (FFA; Heidelberg Retina Angiograph 2; Heidelberg Engineering, Heidelberg, Germany) were performed. The OCT images showed general thinning of the retina and choroid layer, multiple outer retinal tubulations, and hyperreflective dots in the outer retina and choroid. In addition, OCT showed a hyperreflective lesion compatible with active CNVM in the right eye [Figure 1]b. FFA revealed hypoautofluorescent and clearly defined confluent-patched areas corresponding to local RPE and choriocapillaris loss sections at the posterior pole in both eyes. FFA also demonstrated leakage in the right eye suggestive of active CNVM [Figure 1]c and [Figure 1]d. Swept-source optical coherence tomography angiography (SS-OCTA; DRI Triton, Topcon; Tokyo, Japan) revealed a high-flow network corresponding to the hyperreflective lesion detected on the OCT [Figure 1]e.
We explained to the patient the nature of his condition and offered an intravitreal anti-vascular endothelial growth factor (anti-VEGF) injection for CNVM in his right eye. A single dose of intravitreal aflibercept (EYLEA™; Regeneron Pharmaceuticals, Inc., Tarrytown, New York, USA and Bayer HealthCare Pharmaceuticals, Berlin, Germany) was administered to the right eye. After injection, the visual acuity of the patient was increased to 0.05. Fundus examination showed scarred CNVM in the right eye which was confirmed on OCT [Figure 3].
|Figure 3: After intravitreal injection of aflibercept OCT reveals scarred CNVM without intra- or subretinal fluid. OCT - Optic coherence tomography; CNVM - Choroidal neovascular membrane|
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| Discussion|| |
The choroidal neovascular membrane is an uncommon complication in BCD patients. However, the development of CNVM might not be surprising, considering that marked dysfunction of RPE and degeneration of the outer retina occurs in BCD. Many inherited retinal disease processes affecting these layers can also lead to CNVM development, such as Stargardt disease, Best vitelliform dystrophy gyrate atrophy, choroideremia, Sorsby fundus dystrophy, and North Carolina macular dystrophy.,,
The exact pathogenesis of CNVM in BCD patients is still unclear. Mamatha et al. hypothesize that the chronic irritation of Bruch's membrane by the crystals may have provoked CNVM in these patients.
As in previous reports, the CNVM lesion appears to be confined within the foveal/parafoveal retina, but intraretinal crystals tend to be distributed along the posterior pole, Wang et al. claimed that CNVM development is not a direct result of intraretinal crystals.
Fuerst et al. showed that CNVM in BCD patients can be associated with the dysfunction of RPE and abnormalities of photoreceptor outer segment – RPE interface at the fovea and parafovea. Furthermore, they speculated that the development of CNVM in BCD may be a consequence of a reduction of the production of antiangiogenic factors. This hypothesis might explain the observation of CNVM in association with severe RPE atrophy and photoreceptor dysfunction in the foveal and parafoveal regions.
In our case, due to the presence of active CNVM and progressive visual impairment in the right eye, we recommended to the patient anti-VEGF treatment. Our patient's visual acuity slightly improved after single-dose intravitreal aflibercept treatment. Furthermore, there were no findings of active CNVM such as hemorrhages or subretinal fluid. This improvement also might support the role of the VEGF pathway in the pathophysiology of CNVM in BCD.
To the best of our knowledge, a case of CNVM secondary to BCD treated with an intravitreal injection of aflibercept has not been described in the literature. A single dose of aflibercept injection might be effective due to its higher affinity for VEGF in comparison with other anti-VEGFs. It might be a treatment alternative that can be considered in CNVM due to uncommon etiologies.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form, the legal guardian has given her consent for images and other clinical information to be reported in the journal. The guardian understands that her names and initials will not be published and due efforts will be made to conceal the patient's identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3]