[Risk factors of postoperative proliferative vitreoretinopathy in giant tears].

Background: In eyes with giant retinal tears, the rate of severe postoperative PVR and failure to permanently reattach the retina remains especially high in spite of technical advances in surgical management. This study was conducted to elucidate the clinical and surgical risk factors for severe postoperative PVR in such eyes.
Patients and Methods: We reviewed the records of 68 consecutive patients (69 eyes) with giant retinal tears. Univariate and multivariate statistical analyses were used to evaluate the risk factors for severe PVR.
Results: The rate of severe postoperative and failure to permanently reattach the retina were 43.5% (30/69 eyes). It was influenced at a statistically significant level by two independent risk factors: 1) the presence and severity of preoperative PVR and 2) the use of cryotreatment as compared to the use of ALP treatment. Severe postoperative PVR occurred in 63.6% (14/22 eyes) of eyes managed with cryotreatment versus 31.1% (14/45 eyes) of eyes managed with ALP treatment (P < 0.02). The rate of severe postoperative PVR was 64% (16/25 eyes) in eyes with grade C-D PVR preoperatively versus 31.8% (14/44 eyes) in eyes with no PVR or grade B PVR preoperatively (P < 0.01). In eyes managed with the use of ALP treatment the rate of severe postoperative PVR remained influenced at a statistically significant level (P < 0.005) by the presence of grade C-D PVR preoperatively. Grade C-D PVR was significantly more frequent preoperatively in patients with visual symptoms of 3 week-duration or more at initial examination (23/24 patients, 95.8%), than in those with visul symptoms under 3 week-duration (8/41 patients, 19.5%) (P: 0.0005).
Conclusion: The results suggest that the high incidence of severe postoperative PVR in giant retinal tears may be decreased by 1) early management before the occurrence of PVR and 2) the use of argon laser photocoagulation rather than cryotreatment as the method of creating a chorioretinal scar.