Causes of Redetachment Post Vitreoretinal Surgery
The primary causes of retinal redetachment after vitreoretinal surgery are new or missed retinal breaks (particularly at or anterior to the scleral buckle), proliferative vitreoretinopathy (PVR), inadequate vitreous base shaving, and anterior membrane formation.
Intraoperative and Early Postoperative Causes
Retinal Breaks
- New retinal tears occur in 1-3% of cases during vitrectomy, with most located inferiorly at the posterior vitreous base 1
- Small flap tears at the posterior vitreous base are the typical cause of early postoperative detachment, which occurs in 1-5% of cases 1
- Missed retinal breaks at initial surgery are independently correlated with worse anatomic outcomes (P = 0.0114) 2
- In late recurrent detachments (>1 year post-surgery), new breaks account for 50% of cases, reopening of old breaks 30%, and both occur in 20% 3
Location-Specific Risk
- Nine of 13 breaks (69%) in late recurrent detachments occur on or anterior to the scleral buckle, indicating inadequate peripheral support 3
- Inferior detachments are most common due to the location of tears at the inferior vitreous base 1
Proliferative Vitreoretinopathy (PVR)
PVR as Primary Cause
- Grade C PVR is present in 80% of late recurrent detachments, including both anterior and posterior forms 3
- Anterior and posterior PVR, along with perisilicone proliferation, are major factors causing redetachment in complex cases 4
- Redetachment associated with PVR development is significantly correlated with ultimate anatomic failure (P = 0.0036) and worse visual outcomes (P = 0.0029) 2
Anterior PVR Considerations
- Anterior membrane formation requires aggressive surgical management, often necessitating removal of the crystalline lens or IOL to properly access and dissect the retinal periphery 4
Surgical Technique Factors
Inadequate Vitreous Base Management
- Inadequate vitreous base shaving has the highest risk for redetachment (adjusted OR 117.62, P < 0.001) 5
- Vitreous base traction is an important factor in late recurrent detachments, with PVR likely being a secondary phenomenon rather than causative 3
Lack of Scleral Buckling
- Surgeries performed without scleral buckling have nearly double the redetachment risk (adjusted OR 1.97, P = 0.039) 5
- This is particularly relevant when vitreous base pathology is present 5
Specific Clinical Scenarios
Macular Hole Surgery
- Up to 10% of successfully closed macular holes later reopen, though risk is reduced with internal limiting membrane (ILM) peeling 1
- Postoperative retinal detachment occurs in 1-14% of macular hole operations, typically from inferior flap tears 1
- 11% of closed macular holes reopen after subsequent cataract surgery, with cystoid macular edema increasing risk sevenfold 1
High-Risk Populations
- Giant retinal tears carry the highest redetachment risk (adjusted OR 12.39, P < 0.001) 5
- High myopia significantly increases redetachment risk (adjusted OR 2.70, P = 0.011) 5
Silicone Oil Cases
- Retinal incarceration, subretinal membrane formation, and perisilicone proliferation are specific causes in silicone oil-filled eyes 4
- Vitreous hemorrhage at the first postoperative week after silicone oil removal strongly predicts redetachment (adjusted OR 12.13, P < 0.001) 5
Time Course Considerations
- Early redetachments (<1 year) typically result from missed breaks or inadequate initial surgery 3
- Late recurrent detachments (>1 year) occur in 2.2% of cases, with average time to redetachment of 46.8 months 3
- Removal of posteriorly dislocated lens fragments during vitrectomy significantly shortens the interval to detachment (3.89 vs 15.7 months, P = 0.0044) 2
Critical Surgical Principles
The best anatomic and functional results require one radical operation addressing all pathology that could lead to recurrence, including complete anterior membrane dissection and adequate peripheral vitreous removal 4. When anterior pathology is present, lens or IOL removal should not be avoided, as proper peripheral access is essential 4.