Comparison of early versus late laser goniopuncture following deep sclerectomy for the management of open-angle glaucoma

Laser goniopuncture after deep sclerectomy: incidence, long-term outcomes and risk factors for failure

AIMS

To report the incidence, risk factors and long-term outcomes of laser goniopuncture (LGP) in patients with previous deep sclerectomy (DS).

METHODS

Retrospective cohort study of 1765 eyes (1385 patients) undergoing DS with or without cataract surgery between 2001 and 2020 in two UK institutions. Kaplan-Meier was used to estimate LGP incidence. DS success after LGP was calculated for criteria A, B, and C defined as intraocular pressure (IOP) of ≤18, ≤15 and ≤12 mm Hg with 20%, 25% and 30% reduction, respectively. Cox regression was used to investigate factors associated with the risk of failure.

RESULTS

LGP had an estimated incidence of 33.3% (30.9%-35.6%), 56.3% (53.5%-58.9%) and 62.8% (59.7%-65.6%) at 1, 3, 5 years, respectively. Mean (±SD) IOP significantly (p<0.001) decreased from 21.2 (±6.0) mm Hg pre-LGP to 13.8 (±5.2) mm Hg and 12.9 (±4.7) mm Hg at 3 and 5 years post-LGP, respectively. Success rates at 3 and 5 years were, respectively, 40.9% (37.5%-44.6%) and 33.7% (30.3%-37.6%) for criterion A; 27.1% (24.0%-30.5%) and 22.3% (19.3%-25.7%) for criterion B and 13.9% (11.6%-16.7%) and 11.6% (9.5%-14.3%) for criterion C. In all models, higher pre-LGP IOP (p<0.001) and higher pre-LGP medication number (p<0.001) were associated with increased failure, while male gender (p≤0.004), intraoperative mitomycin C (p≤0.031), longer interval between DS and LGP (p≤0.01) with reduced failure.

CONCLUSION

Most patients undergoing DS will eventually require LGP. LGP is effective at rescuing eyes with a failing DS. This study identifies several factors associated with LGP outcomes, knowledge of which may help clinicians predict LGP success.

Rotational extraction of incarcerated iris (REII): a slit lamp technique to reduce incarcerated iris after nonpenetrating deep sclerectomy for glaucoma

PURPOSE

Iris incarceration is a complication of glaucoma filtering surgery that often requires surgery. We describe a technique for reduction of incarcerated iris at the slit lamp, dubbed rotational extraction of incarcerated iris (REII). A retrospective analysis of visual function and intraocular pressure (IOP) was done in patients treated with REII after nonpenetrating deep sclerectomy.

METHODS

We retrospectively evaluated a cohort of patients who received REII for iris incarceration after nonpenetrating deep sclerectomy for glaucoma. IOP (applanation) and visual acuity (VA) were measured day-of, and 1, 3, 6, and 12 months post-REII. Adverse events were recorded. Kaplan-Meier survival analysis was done with definitions of IOP control at 15, 18, and 21 mmHg.

RESULTS

Forty-one eyes of 41 patients were treated with REII. Median time to iris incarceration from glaucoma surgery was 50 days (range 1-1906). Mean pre-REII IOP ± SD was 33.7 ± 14.1 mmHg, which reduced to 11.5 ± 6.1 mmHg day-of. LogMAR VA was 0.72 ± 0.8 log units at baseline and was unchanged at 12 months (P = 0.53). Survival analysis demonstrated varying efficacy depending on the definition of success. 79.0 to 92.2% of eyes achieved IOP control immediately after REII, 39.5 to 71.1% at 1 month, 26.3 to 52.6% at 3 months, 21.1 to 44.3% at 6 months, and 10.5 to 38.0% at 12 months. Nearly half (47.4%) of eyes required a tube shunt by 12 months.

CONCLUSION

REII may be a safe, minimally invasive slit lamp procedure that can reduce incarcerated iris and delay more invasive intervention for 3-6 months in most eyes.

Safety, efficacy, and timing of Nd:YAG laser goniopuncture after nonpenetrating deep sclerectomy for glaucoma: A retrospective cohort study

BACKGROUND

Neodymium-doped yttrium aluminum garnet laser goniopuncture is an adjuvant procedure for nonpenetrating deep sclerectomy. We investigated optimal laser goniopuncture timing and the effect of laser iridoplasty on success rates.

METHODS

This single-center retrospective cohort study compared intraocular pressure control in patients with early versus late laser goniopuncture after nonpenetrating deep sclerectomy and evaluated the effects of laser iridoplasty pretreatment. A 3-month cut-off was used to define early versus late laser goniopuncture. The primary outcome was the proportion of patients maintaining intraocular pressure control according to definitions of complete (no medications) and qualified (with medications) success at 15, 18, and 21 mmHg thresholds. Data were analyzed using right-censored Kaplan-Meier estimation and log-rank testing.

RESULTS

A total of 124 eyes of 124 patients were analyzed. Complete success rates after 3 years were 9.2%, 14.6%, and 23.3% for early laser goniopuncture and 21.8%, 26.0%, and 55.4% for late laser goniopuncture for 15, 18, and 21 mmHg, respectively (all p < .01). Qualified success rates after 3 years were 16.6%, 24.8%, and 40.9% for early laser goniopuncture and 21.5%, 56.1%, and 69.6% for late laser goniopuncture for 15, 18, and 21 mmHg, respectively (p  =  .096, .0026, .0061). Late laser goniopuncture was associated with decreased risk of iris incarceration and bleb collapse. Iridoplasty pretreatment was not associated with improved outcomes.

CONCLUSION

Late laser goniopuncture (3-month cut-off) was associated with better intraocular pressure control and less adverse events than early laser goniopuncture.

XEN-Augmented Deep Sclerectomy: Step-by-step Description of a Novel Surgical Technique for the Management of Open-angle Glaucoma

AIM AND BACKGROUND

The present case report describes a novel surgical technique combining XEN gel stent implantation and deep sclerectomy: XEN-augmented deep sclerectomy (XEN-DS).

CASE DESCRIPTION

An active 96-year-old Caucasian woman suffering from pseudoexfoliative glaucoma (PEXG) presented with intraocular pressure (IOP) of 24 mm Hg and a double arcuate visual field defect [mean deviation (MD) -9.6 dB] in her only functional eye despite maximal medical therapy. Considering (1) the magnitude of IOP reduction sought, (2) the risk of complications associated with trabeculectomies and glaucoma drainage devices, and (3) the risk of missed appointments due to the patient's personal and social circumstances, it was decided to tailor the surgical treatment to this patient's specific characteristics combining two existing surgical techniques. Following conjunctival dissection, a superficial scleral flap was lifted 2 mm more posteriorly than in conventional DS, and a XEN gel stent was implanted ab externo through the anterior wall of the deep sclerectomy, into the anterior chamber. A mitomycin C-soaked autologous space maintainer was used. No peri- or postoperative complications were observed. Following XEN-DS, her IOP stabilized between 5 mm Hg and 8 mm Hg through 6 months, and her visual field MD improved to -1.5 dB.

DISCUSSION

The present case report is a proof of concept for this novel surgical technique, confirming that XEN-DS has the potential to achieve substantial and persistent IOP reductions in PEXG with a satisfactory safety profile. Clinical studies are warranted to confirm these results.

HOW TO CITE THIS ARTICLE

Niegowski LJ, Gillmann K, Baumgartner JM. XEN-Augmented Deep Sclerectomy: Step-by-step Description of a Novel Surgical Technique for the Management of Open-angle Glaucoma. J Curr Glaucoma Pract 2021;15(3):144-148.