Most Common Cause of Bullous Retinoschisis
Central serous chorioretinopathy (CSC) is the most common cause of bullous retinoschisis, particularly in its rare bullous form which can lead to extensive subretinal fluid and exudative neuroretinal detachment. 1
Pathophysiology of Bullous Retinoschisis in CSC
Bullous CSC represents an uncommon but severe variant of central serous chorioretinopathy with distinctive characteristics:
- Multiple retinal pigment epithelial detachments (PEDs) are typically present beneath extensive subretinal fluid (SRF) 1
- Each PED can evolve into a retinal pigment epithelium (RPE) tear, potentially leading to exudative retinal detachment 1
- The condition is characterized by shifting subretinal fluid and exudative neuroretinal detachment 1
Clinical Presentation and Risk Factors
Patients with bullous CSC typically present with:
- Decreased central vision
- Visual distortion
- Altered color perception
- Shifting fluid that may cause changing visual symptoms
Risk factors that may contribute to development of bullous CSC include:
- Male gender (CSC is 3.5 times more common in men than women) 1
- Age between 35-50 years (though can occur from age 7-83) 1
- Corticosteroid use (systemic corticosteroids can exacerbate CSC and lead to bilateral bullous serofibrinous exudative retinal detachment) 2
- Type A personality traits 2
Differential Diagnosis
It's important to distinguish bullous CSC from other causes of bullous retinoschisis:
- X-linked retinoschisis (XLRS) - typically presents in childhood with strabismus, can have bilateral bullous schisis cavities 3
- Degenerative retinoschisis - characterized by elevation of inner layers of peripheral retina, usually benign unless complicated by retinal layer breaks 4
- Vascular abnormalities - sclerotic retinal vessels and neovascularization can occur over schisis cavities in some cases 5
Complications and Prognosis
Bullous CSC can lead to serious complications:
- RPE tears and subsequent exudative retinal detachment 1
- Progressive damage to macular photoreceptors 1
- Decreased best-corrected visual acuity (BCVA) and contrast sensitivity 1
- Up to 13% of eyes with chronic CSC can develop legal blindness (20/200 or worse) after 10 years 1
- Secondary macular neovascularization (MNV) 1
- Posterior cystoid retinal degeneration (PCRD) 1
Management Considerations
Treatment should focus on addressing the underlying CSC:
- Photodynamic therapy (PDT) can stabilize or improve BCVA in severe forms of chronic CSC 1
- Avoid systemic corticosteroids, as they may cause severe exacerbation of retinal detachment and lasting visual loss 2
- Regular monitoring with multimodal imaging is essential for disease monitoring 4
- Surgical intervention may be necessary for progressive symptomatic schisis-related retinal detachment 4
Important Caveats
- Misdiagnosis of bullous CSC can lead to inappropriate treatment with corticosteroids, potentially worsening the condition 2
- Bilateral involvement is common in severe CSC phenotypes, with up to 84% of cases showing bilateral disease activity 1
- Patients with bilateral severe CSC have a higher risk of developing severe, irreversible visual impairment 1
- The disease course of severe CSC is typically progressive but can be slowed with appropriate treatment 1
Early recognition and appropriate management of bullous CSC are crucial to prevent permanent vision loss and improve quality of life outcomes for affected patients.