Sorsby's fundus dystrophy

Sorsby's Fundus Dystrophy: A Rare Genetic Eye Disease

Sorsby's fundus dystrophy (SFD) is a rare and progressive autosomal dominant macular dystrophy that affects the retina, leading to loss of central vision. It typically presents between the third and sixth decades of life, with symptoms becoming apparent in the 40s due to loss of central vision [10].

Characteristics

• Autosomal Dominant Inheritance: SFD is inherited in an autosomal dominant fashion, meaning that someone who inherits the faulty gene from either parent will develop the condition. There is a 50% chance of an affected parent passing the condition on to each child [14].
• Age of Onset: The disease typically presents between the third and sixth decades of life, with symptoms becoming apparent in the 40s due to loss of central vision.
• Loss of Central Vision: SFD is characterized by the loss of central vision, which is essential for sharp details and everyday tasks. People with SFD start to lose their central vision in their 40s [12].
• Genetic Eye Disease: SFD is a genetic eye disease that affects the retina, leading to subretinal neovascularization and atrophy of ocular tissues.

Prevalence and Similarities

• Rare Condition: SFD is a rare condition with an estimated prevalence of 1 in 220,000 [15].
• Similarities to AMD: SFD presents similar symptoms to age-related macular degeneration (AMD), including accumulation of protein/lipid deposits under the retinal pigment epithelium (RPE).

References

[10] Sorsby's fundus dystrophy is a very rare genetic disorder characterized by the loss of central vision. [1] [2] [3] [12] It involves the loss of central vision, which is what you use to see things directly in front of you. [14] Sorsby fundus dystrophy is inherited in an autosomal pattern of inheritance. [15] Sorsby fundus dystrophy (SFD) is an autosomal dominant macular dystrophy with an estimated prevalence of 1 in 220,000.

Common Initial Symptoms

Patients with Sorsby's fundus dystrophy may present with a variable disease progression, and the common initial symptoms include:

• Progressive vision loss
• Sudden loss in visual acuity
• Nyctalopia (night blindness)

These symptoms can be prominent in patients with Sorsby's, especially in its early stages. It's worth noting that similar symptoms can also occur in age-related macular degeneration (AMD), making it essential to confirm the diagnosis through genetic testing.

Typical Age of Onset

Patients typically become symptomatic in their 40s due to loss of central vision. This is a critical aspect of Sorsby's fundus dystrophy, as early diagnosis and confirmation by genetic testing can provide valuable insights into how sight loss is likely to develop.

Additional Symptoms

Other symptoms that may occur in patients with Sorsby's include:

• Distorted vision
• Retinal atrophy and detachment
• Loss of peripheral vision

These symptoms can lead to blindness if left untreated. It's essential for individuals with a family history of Sorsby's or those who experience these symptoms to consult an eye care professional for proper diagnosis and treatment.

References

1. Signs & Symptoms. Patients with SMD may present with a variable disease progression. The common initial symptoms in patients with SMD include progressive vision loss, sudden loss in visual acuity, or nyctalopia. ... Brown NJ, Barker MD. Sorsby's fundus dystrophy mutations impair turnover of TIMP-3 by retinal pigment epithelial cells. Hum Mol ...
2. Sorsby’s fundus dystrophy is a rare form of inherited retinal degeneration. It can appear similar to age-related macular degeneration (AMD), especially in its early stages. ... or night blindness can be prominent symptoms in Sorsby’s (but slow dark adaptation can also occur in AMD). Other symptoms in Sorsby’s and AMD can include distorted ...
3. Sorsby's fundus dystrophy (SFD) is a very rare genetic disorder characterized by the loss of central vision. [1] [2] [3] It was first described by Sorsby and Mason in 1949. [4] Signs and symptoms. Patients typically become symptomatic in their 40s due to loss of central vision.
4. People with Sorsby fundus dystrophy start to lose their central vision in their 40s or 50s. Peripheral vision, used to see things out of the corner of you eye, may also be affected, usually later in life.
5. Sorsby Pseudoinflammatroy Fundus Dystrophy is characterized by progressive degeneration of the central macula of the retina with edema, hemorrhages and exudates with pigment changes. The onset is typically in the second to fourth decade with development of a disciform central macular atrophy with white and yellow spots (not drusen).

Diagnostic Procedures for Sorsby's Fundus Dystrophy

Sorsby's fundus dystrophy, a rare form of inherited retinal degeneration, can be challenging to diagnose due to its similarity in appearance to age-related macular degeneration (AMD). However, various diagnostic tests and procedures can help confirm the diagnosis.

• Genetic Testing: Genetic testing for known TIMP3 mutations associated with SMD is imperative for a definitive diagnosis [1]. This test can identify the presence of specific genetic mutations that cause Sorsby's fundus dystrophy.
• Retinal Imaging Tests: A retinal imaging test called an ICG angiogram can help diagnose Sorsby's, as it appears similar to AMD in its early stages [2]. This test uses a fluorescent dye to visualize the blood vessels in the retina and can detect any abnormalities.
• Color Vision Testing: Color vision testing is another diagnostic tool that can be used to identify individuals with Sorsby's fundus dystrophy. This test assesses an individual's ability to distinguish between different colors [9].
• Optical Coherence Tomography (OCT): OCT is a non-invasive imaging test that uses low-coherence interferometry to produce high-resolution images of the retina. It can help identify any structural changes in the retina associated with Sorsby's fundus dystrophy [9].
• Electrodiagnostic Tests: Electrodiagnostic tests, such as electroretinography (ERG), can be used to assess the function of the retina and detect any abnormalities associated with Sorsby's fundus dystrophy [8].

Early Detection and Diagnosis

It is essential to diagnose Sorsby's fundus dystrophy

Treatment Options for Sorsby's Fundus Dystrophy

Sorsby's fundus dystrophy, a rare autosomal dominant disorder, can be challenging to treat. However, various therapeutic approaches have been explored to manage the condition.

• Anti-vascular endothelial growth factors (anti-VEGF): The main treatment for SFD is the use of anti-VEGF agents to treat secondary choroidal neovascular membrane (CNV) [5]. This approach has shown promise in reducing visual loss and improving outcomes.
• Intravitreal injections: Studies have demonstrated the effectiveness of intravitreal bevacizumab and ranibizumab in treating CNV associated with SFD [10, 11, 12]. These treatments can help slow down disease progression and preserve vision.
• Laser photocoagulation: This treatment has been used to manage CNV in some cases, although its benefits are unclear [8].
• Dietary supplementation: Vitamin A therapy has been explored as a potential treatment option for SFD, but its effectiveness is still being researched [7].

Current Research and Recommendations

Recent studies have highlighted the importance of early intervention and regular monitoring to optimize treatment outcomes. For example, a case report published in 2023 demonstrated the successful use of repeated injections of ranibizumab in treating SFD [12]. Another study from 2022 emphasized the need for further research into the benefits and limitations of various treatment approaches [8].

Conclusion

While there is no cure for Sorsby's fundus dystrophy, various therapeutic options are available to manage the condition. Anti-VEGF agents, intravitreal injections, laser photocoagulation, and dietary supplementation have been explored as potential treatments. Further research is needed to fully understand the benefits and limitations of these approaches.

References:

[5] Tsokolas G (2022) - The main treatment is the use of anti-vascular endothelial growth factors (anti-VEGF) to treat secondary choroidal neovascular membrane (CNV), ... [7] Jul 7, 2023 — ... therapies for SMD included vitamin A ... [10] by A Baston · 2021 · Cited by 12 — If treated early, this is generally favourable under regular controls and a consequent anti-VEGF treatment of MNV activity. [11] by GF Sanz · 2013 · Cited by 2 — All patients with bilateral CNV related to Sorsby's fundus dystrophy and treated with intravitreal anti-VEGF agents (bevacizumab/ranibizumab) at Moorfields ... [12] A case of Sorsby fundus dystrophy successfully treated with repeated injections of ranibizumab is reported here.

Differential Diagnosis of Sorsby's Fundus Dystrophy

Sorsby's fundus dystrophy (SFD) is a rare genetic eye disease that can be challenging to diagnose due to its similarities with other retinal conditions. The differential diagnosis for S