Minimally Invasive Glaucoma Surgery: Latest Developments and Future Challenges

Long-term Efficacy and Safety of Posterior Endoscopic Cyclophotocoagulation in Refractory Glaucoma: A 5-Year Follow-up Study at a Tertiary Eye Center

PURPOSE

To evaluate the long-term efficacy of endoscopic cyclophotocoagulation (ECP) via a pars plana approach in a large cohort of refractory glaucoma patients DESIGN: Single-center, retrospective, longitudinal, cohort study.

METHODS

This study recruited patients who underwent ECP and consecutively visited and were followed up for at least 5 years at Beijing Tongren Eye Center, China from January 2013 to December 2017. All patients underwent a complete ophthalmic examination. Treatment success was defined as 6mmHg ≤ IOP ≤ 21mmHg with or without anti-glaucoma medications.

RESULTS

A total of 121 eyes of 105 patients including 51 children and 54 adults were enrolled. The mean follow-up was 7.2±1.3 years. The most common glaucoma diagnoses were secondary glaucoma (74 eyes, 61.1%) and primary congenital glaucoma (19 eyes 15.7%). The mean extent of the first ECP was 259 degrees. There was an overall decrease in IOP of 38.3% from 33.3±9.0mmHg preoperatively to 20.5±7.5mmHg after surgery, which was statistically significant (P < 0.001). The success rate after 1 or more ECP surgery was 65.3%. After adjusting for sex, number of prior TCP surgeries and the extent of ECP degree, the failure of ECP was associated with being children (as compared with adults; P = 0.028; OR = 2.549) and higher preoperative IOP (P = 0.001; OR = 1.084).

CONCLUSION

ECP is an effective procedure for lowing IOP in refractory glaucoma, particularly in patients who are also candidates for vitreoretinal interventions. Hence, a collaborative approach between glaucoma and retinal specialists is of utmost importance in devising an optimal management strategy for glaucoma treatment.

CRISPR-Cas9-mediated deletion of carbonic anhydrase 2 in the ciliary body to treat glaucoma

The carbonic anhydrase 2 (Car2) gene encodes the primary isoenzyme responsible for aqueous humor (AH) production and plays a major role in the regulation of intraocular pressure (IOP). The CRISPR-Cas9 system, based on the ShH10 adenovirus-associated virus, can efficiently disrupt the Car2 gene in the ciliary body. With a single intravitreal injection, Car2 knockout can significantly and sustainably reduce IOP in both normal mice and glaucoma models by inhibiting AH production. Furthermore, it effectively delays and even halts glaucomatous damage induced by prolonged high IOP in a chronic ocular hypertension model, surpassing the efficacy of clinically available carbonic anhydrase inhibitors such as brinzolamide. The clinical application of CRISPR-Cas9 based disruption of Car2 is an attractive therapeutic strategy that could bring additional benefits to patients with glaucoma.

Changes in Ocular Biometry Following PreserFlo MicroShunt Implantation and Trabeculectomy: A Prospective Observational Study

Background This study aimed to evaluate postoperative changes in ocular biometry following initial PreserFlo MicroShunt implantation and trabeculectomy. Methodology This prospective, observational study analyzed 27 cases of PreserFlo MicroShunt implantation and 29 cases of trabeculectomy performed by a single surgeon. Visual acuity, intraocular pressure, corneal curvature, central corneal thickness, anterior chamber depth, and axial length were assessed at baseline and postoperatively at one day, one week, two weeks, one month, two months, three months, and six months. Patients requiring additional surgery and those with missing data were excluded. Consecutive data were compared with the baseline values using multiple comparisons. Results In both groups, intraocular pressure was significantly decreased from baseline at all postoperative time points (all p < 0.01). Visual acuity decreased in both groups at one day and one week postoperatively. Corneal curvature remained unchanged in both groups throughout the six-month follow-up. Central corneal thickness increased at one day and one week postoperatively in the PreserFlo group, but not in the trabeculectomy group. Anterior chamber depth exhibited a significant decrease at one week postoperatively in both groups. Axial length significantly decreased postoperatively until three months in the PreserFlo group and at all postoperative time points in the trabeculectomy group. Conclusions Ocular biometry following PreserFlo and trabeculectomy had a similar tendency postoperatively.

Phacogoniotomy versus phacotrabeculectomy for advanced primary angle-closure glaucoma with cataract: A randomized non-inferiority trial

PURPOSE

To investigate the effectiveness and safety of phacogoniotomy versus phacotrabeculectomy (PVP) among patients with advanced primary angle-closure glaucoma (PACG) and cataracts.

DESIGN

Multicenter, randomized controlled, non-inferiority trial.

METHODS

A total of 124 patients (124 eyes) with advanced PACG and cataracts were enrolled, with 65 in the phacogoniotomy group and 59 in the phacotrabeculectomy group. Patients were followed up for 12 months with standardized evaluations. The primary outcome was the reduction in intraocular pressure (IOP) from baseline to 12 months postoperatively, of which a non-inferiority margin of 4 mmHg was evaluated. Secondary outcomes included the cumulative surgical success rate, postoperative complications, and changes in the number of glaucoma medications.

RESULTS

After 12 months, phacogoniotomy demonstrated non-inferiority to phacotrabeculectomy in terms of IOP reduction, with mean IOP reductions of - 26.1 mmHg and - 25.7 mmHg (P = 0.383), respectively, from baseline values of around 40 mmHg. Both groups experienced a significant reduction in the mean number of medications used postoperatively (P < 0.001). The cumulative success rate was comparable between the groups (P = 0.890). However, phacogoniotomy had a lower rate of postoperative complications and interventions (12.3% and 4.6%) compared to phacotrabeculectomy (23.7% and 20.3% respectively). The phacogoniotomy group reported shorter surgery time (22.1 ± 6.5 vs. 38.8 ± 11.1 min; P = 0.030) and higher quality of life (EQ-5D-5 L) improvement at 12 months (7.0 ± 11.5 vs. 3.0 ± 12.9, P = 0.010) than the phacotrabeculectomy group.

CONCLUSIONS

Phacogoniotomy was non-inferior to phacotrabeculectomy in terms of IOP reduction for advanced PACG and cataracts. Additionally, phacogoniotomy provided a shorter surgical time, lower postoperative complication rate, fewer postoperative interventions, and better postoperative quality of life.

The Evolution and Current Landscape of Minimally Invasive Glaucoma Surgeries: A Review

This review examines the evolution, current status, and future potential of minimally invasive glaucoma surgeries (MIGS), a significant advancement in the treatment of glaucoma, a leading cause of irreversible blindness. MIGS offer a less invasive alternative to traditional glaucoma surgeries, primarily aimed at reducing intraocular pressure, minimizing tissue trauma, and providing a safer profile. With the emergence of devices such as the Trabectome, iStent, and others, MIGS have expanded the surgical toolkit, allowing personalized, patient-centered care. Despite their advantages, MIGS face challenges such as efficacy in severe cases, long-term data, and accessibility. Ongoing research and technological innovations continue to refine their capabilities and applications, promising to further transform glaucoma management and patient outcomes. This paper provides an in-depth analysis of MIGS, reflecting on their impact and contemplating future directions in this dynamically evolving field.