Pars Planectomy: Preliminary Report of a New Glaucoma Filtering Technique in Vitrectomized Eyes

To propose a new filtering technique in vitrectomized eyes with glaucoma and report its clinical results and safety.

The medical records of 13 eyes that developed glaucoma following pars plana vitrectomy and underwent pars planectomy, from 2011 to 2018, at Songklanagarind hospital, Hatyai, Songkhla, Thailand were retrospectively reviewed. The main outcome measures were visual acuity (VA), intraocular pressure (IOP), number of glaucoma medications, and postoperative complications. Surgical success was defined as IOP value at the last visit of 6-21 mmHg, regardless of anti-glaucoma medication usage, and without further glaucoma surgery.

The mean follow-up duration was 47.7 ± 32.1 months (range, 0.3-101.1 months). Preoperative BCVA increased from LogMAR 1.01 ± 0.85 to 1.2 ± 0.91 at the last visit (p = 0.233). The mean preoperative IOP was 28.15 ± 9.17 mmHg with an average of 3.46 ± 0.52 anti-glaucoma medications. At the final visit, the mean IOP was 14.08 ± 4.89 mmHg (p = 0.006) and the mean number of anti-glaucoma medications decreased to 1.31 ± 1.38 (p = 0.000). The probability of surgical success was 58.3%, 50%, and 37.5% at 1, 2, and 6 years after pars planectomy, respectively. Postoperative complications included vitreous hemorrhage in 1 eye (7.7%). No retina and pars plicata associated complications were found.

Pars planectomy is efficient and safe as well as requires a short learning curve. It should be considered as an alternative filtering surgery in glaucoma after vitrectomy, especially with an extensive limbal scar that might be a limitation in trabeculectomy and GDDs techniques and outcomes.