Study design

The PIVOT trial is a 4-year prospective, single center, randomized study. Researchers recruited patients diagnosed with RRD with a single break or group of breaks within 1 clock hour, above the 8 and 4 o’clock meridians. Randomization was stratified based on macular involvement. Of the 176 patients enrolled in the study, 77 patients in the PnR and 73 in the vitrectomy group completed the 1-year assessment.

The primary outcome was 1-year ETDRS visual acuity. Secondary outcomes included primary anatomical success, vision-related quality of life (NEI VFQ-25), metamorphopsia scores, cataract grading and extraction, and number of visits.

Outcomes

At 12 months, the ETDRS visual acuity was significantly higher in the PnR arm than in the vitrectomy arm (80 vs. 75; P=0.024). However, the primary anatomic success rate was higher with vitrectomy (93.2% vs. 80.8% for PnR; P=0.045). Of note, the secondary anatomic success was similar (both 98%).

The NEI VFQ-25 scores were significantly higher in the PnR group at 3 and 6 months, but was comparable between groups at 1 year. PnR patients had significantly better vertical metamophopsia scores and non-significantly better horizontal metamorphopsia scores (P=0.026 and P=0.25, respectively).

By 12 months, 65% of the phakic patients in the vitrectomy group underwent cataract surgery, compared with 16% in the PnR group. Patients in the PnR group attended more office visits than those in the vitrectomy arm (10.8 vs. 9.6; P<0.001) due to necessary laser retinopexy following PnR.

Limitations

Although this study reports better visual acuity after PnR than with vitrectomy at all timepoints, the difference decreased as the study progressed. The early advantage in the NEI-VFQ 25 scores was also lost by 12 months. The large proportion of cataract surgeries performed in the vitrectomy group suggests that cataract progression likely played a role in the visual acuity differences. This is further supported by the higher mean cataract grade for all vitrectomy patients despite the large number of patients who underwent cataract surgery.

Clinical significance

This study supports the use of pneumatic retinopexy for retinal detachments that meet the study criteria (a single break or group of breaks within 1 clock hour, above the 8 and 4 o’clock meridians). Patients who underwent PnR had better visual acuity outcomes compared with patients who underwent vitrectomy. However, the impact of cataract progression may have contributed to this outcome. Pneumatic retinopexy reduced metamorphopsia scores and cataract progression and maintained good visual outcomes, despite a lower primary anatomic success rate. It is therefore is a good option for certain retinal detachment cases, but the best surgical management of a retinal detachment also depends on each surgeon's experience and outcomes with different surgical techniques.