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

Optical Study of Lysozyme Molecules in Aqueous Solutions after Exposure to Laser-Induced Breakdown

The properties of a lysozyme solution under laser-induced breakdown were studied. An optical breakdown under laser action in protein solutions proceeds with high efficiency: the formation of plasma and acoustic oscillations is observed. The concentration of protein molecules has very little effect on the physicochemical characteristics of optical breakdown. After exposure to optical breakdown, changes were observed in the enzymatic activity of lysozyme, absorption and fluorescence spectra, viscosity, and the sizes of molecules and aggregates of lysozyme measured by dynamic light scattering. However, the refractive index of the solution and the Raman spectrum did not change. The appearance of a new fluorescence peak was observed upon excitation at 350 nm and emission at 434 nm at exposure for 30 min. Previously, a peak in this range was associated with the fluorescence of amyloid fibrils. However, neither the ThT assay nor the circular dichroism dispersion confirmed the formation of amyloid fibrils. Probably, under the influence of optical breakdown, a small part of the protein degraded, and a part changed its native state and aggregated, forming functional dimers or “native aggregates”.

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.