Incidence of Failure After Scleral Buckling and Cryotherapy
The failure rate after scleral buckling with cryotherapy for primary rhegmatogenous retinal detachment ranges from 7-18%, with most contemporary series reporting initial failure rates of approximately 7-13%. 1, 2, 3
Primary Failure Rates
The most recent high-quality evidence demonstrates:
- Initial anatomical failure occurs in 7.4-13% of cases after primary scleral buckling with cryotherapy for uncomplicated retinal detachment 2, 3
- A large retrospective series of 530 consecutive scleral buckling procedures reported an overall surgical failure rate of 13% (69/530 eyes) 3
- Another contemporary series of 244 eyes showed a 7.4% redetachment rate (18/244 eyes) after initial surgery 2
- Historical data from 175 consecutive cases reported an 18% initial failure rate (32/175 patients) 4
Final Success Rates After Reoperation
Final anatomical success after additional interventions reaches 90-99% across multiple series:
- One series achieved 98.8% final reattachment (241/244 eyes) after secondary procedures 2
- Another reported 90% final success (158/175 cases) after repeat interventions 4
- Of patients requiring reoperation, 46% needed one additional surgery and 53% required two or more interventions to achieve final reattachment 3
Causes of Failure
The primary mechanisms of failure include:
- New break development: 44% of failures, occurring in 10-16% of patients during long-term follow-up 1, 5, 2
- Inadequate sealing of existing breaks: 28% of failures, particularly at the anterior border of horseshoe tears where visualization is difficult 1, 2
- Missed retinal breaks: 22% of failures 2
- Buckle malposition: A significant contributor when treatment doesn't extend adequately to the ora serrata 1, 4
- Proliferative vitreoretinopathy (PVR): Accounts for 5% of all failures (27/530 cases) and represents a distinct failure mechanism 3
Risk Factors for Failure
PVR-associated failure has specific risk factors:
- Smoking history (odds ratio 28.8) 3
- Preoperative vitreous hemorrhage (odds ratio 8.2) 3
- Preoperative PVR (odds ratio 22.7) 3
- Delayed presentation after symptom onset 3
Technical risk factors include:
- Insufficient anterior extension of cryotherapy treatment 1
- Pseudophakic status increases risk of new break formation 1
- The chorioretinal adhesion from cryotherapy is not firm for up to 1 month post-treatment, during which vitreous traction can pull tears beyond treated areas 1, 5
Comparative Context
The American Academy of Ophthalmology guidelines note low to very low certainty evidence showing little or no difference between pars plana vitrectomy and scleral buckling in anatomical and visual outcomes, indicating that scleral buckling with cryotherapy remains a comparable surgical approach 1
A randomized trial comparing cryotherapy versus laser photocoagulation in scleral buckle surgery showed similar reattachment rates: 93% vs 95% at 1 week, with 100% success in both groups by 6 months after secondary procedures 6
Critical Technical Considerations
- Complete visualization and treatment of horseshoe tears to their anterior border is essential 1
- Treatment must extend to the ora serrata if tears cannot be completely surrounded 1
- The 1-month period before chorioretinal adhesion becomes firm represents a vulnerable window for failure 1, 5
- Proliferative complications occurred in 10% of cases in one historical series, though this did not support a causal relationship with thermal treatment 4